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Find video protocols related to scientific articles indexed in Pubmed.
Osteomalacia complicating renal tubular acidosis in association with Sjogren's syndrome.
Saudi J Kidney Dis Transpl
PUBLISHED: 09-07-2014
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Renal involvement in Sjogren's syndrome (SS) is not uncommon and may precede other complaints. Tubulointerstitial nephritis is the most common renal disease in SS and may lead to renal tubular acidosis (RTA), which in turn may cause osteomalacia. Nevertheless, osteomalacia rarely occurs as the first manifestation of a renal tubule disorder due to SS. We herewith describe a 43-year-old woman who was admitted to our hospital for weakness, lumbago and inability to walk. X-ray of the long bones showed extensive demineralization of the bones. Laboratory investigations revealed chronic kidney disease with serum creatinine of 2.3 mg/dL and creatinine clearance of 40 mL/min, hypokalemia (3.2 mmol/L), hypophosphatemia (0.4 mmol/L), hypocalcemia (2.14 mmol/L) and hyperchloremic metabolic acidosis (chlorine: 114 mmol/L; alkaline reserve: 14 mmol/L). The serum alkaline phosphatase levels were elevated. The serum levels of 25-hydroxyvitamin D and 1,25-dihydroxy vitamin D were low and borderline low, respectively, and the parathyroid hormone level was 70 pg/L. Urinalysis showed inappropriate alkaline urine (urinary PH: 7), glycosuria with normal blood glucose, phosphaturia and uricosuria. These values indicated the presence of both distal and proximal RTA. Our patient reported dryness of the mouth and eyes and Schirmer's test showed xerophthalmia. An accessory salivary gland biopsy showed changes corresponding to stage IV of Chisholm and Masson score. Kidney biopsy showed diffuse and severe tubulo-interstitial nephritis with dense lymphoplasmocyte infiltrates. Sicca syndrome and renal interstitial infiltrates indicated SS as the underlying cause of the RTA and osteomalacia. The patient received alkalinization, vitamin D (Sterogyl ®), calcium supplements and steroids in an initial dose of 1 mg/kg/day, tapered to 10 mg daily. The prognosis was favorable and the serum creatinine level was 1.7 mg/dL, calcium was 2.2 mmol/L and serum phosphate was 0.9 mmol/L.
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Subcutis calcinosis caused by injection of calcium-containing heparin in a chronic kidney injury patient.
Saudi J Kidney Dis Transpl
PUBLISHED: 09-07-2014
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Subcutis calcinosis, characterized by abnormal calcium deposits in the skin, is a rare complication of using calcium-containing heparin occurring in patients with advanced renal failure. We report the case of an 83-year-old female, a known case of chronic kidney disease (CKD) for four years with recent worsening of renal failure requiring hospitalization and hemodialysis. She developed subcutis calcinosis following injection of calcium-containing heparin. Biochemical tests showed serum parathormone level at 400 pg/dL, hypercalcemia, elevated calcium-phosphate product and monoclonal gammopathy related to multiple myeloma. She developed firm subcutaneous nodules in the abdomen and the thighs, the injection sites of Calciparin ® (calcium nadroparin) that was given as a preventive measure against deep vein thrombosis. The diagnosis of subcutis calcinosis was confirmed by the histological examination showing calcium deposit in the dermis and hypodermis. These lesions completely disappeared after discontinuing calcium nadroparin injections. Subcutis calcinosis caused by injections of calcium-containing heparin is rare, and, to the best our knowledge, not more than 12 cases have been reported in the literature. Pathogenesis is not well established but is attributed to the calcium disorders usually seen in advanced renal failure. Diagnosis is confirmed by histological tests. Outcome is mostly favorable. The main differential diagnosis is calciphylaxis, which has a poor prognosis. Even though rarely reported, we should be aware that CKD patients with elevated calcium-phosphorus product can develop subcutis calcinosis induced by calcium-containing heparin. When it occurs, fortunately and unlike calciphylaxis, outcome is favorable.
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Novel de novo SPOCK1 mutation in a proband with developmental delay, microcephaly and agenesis of corpus callosum.
Eur J Med Genet
PUBLISHED: 02-13-2014
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Whole exome sequencing made it possible to identify novel de novo mutations in genes that might be linked to human syndromes (genotype first analysis). We describe a female patient with a novel de novo SPOCK1 variant, which has not been previously been associated with a human phenotype. Her features include intellectual disability with dyspraxia, dysarthria, partial agenesis of corpus callosum, prenatal-onset microcephaly and atrial septal defect with aberrant subclavian artery. Previous genetic, cytogenomic and metabolic studies were unrevealing. At age 13 years, exome sequencing on the patient and her parents revealed a de novo novel missense mutation in SPOCK1 (coding for Testican-1) on chromosome 5q31: c.239A>T (p.D80V). This mutation affects a highly evolutionarily conserved area of the gene, replacing a polar aspartic acid with hydrophobic nonpolar valine, and changing the chemical properties of the protein product, likely representing a pathogenic variant. Previous microdeletions of 5q31 including SPOCK1 have suggested genes on 5q31 as candidates for intellectual disability. No mutations or variants in other genes potentially linked to her phenotype were identified. Testicans are proteoglycans belonging to the BM-40/SPARC/osteonectin family of extracellular calcium-binding proteins. Testican-1 is encoded by the SPOCK1 gene, and mouse models have been shown it to be strongly expressed in the brain and to be involved in neurogenesis. We hypothesize that because this gene function is critical for neurogenesis, mutations could potentially lead to a phenotype with developmental delay and microcephaly.
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An antilisterial bacteriocin BacFL31 produced by Enterococcus faecium FL31 with a novel structure containing hydroxyproline residues.
Anaerobe
PUBLISHED: 02-05-2014
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A new bacterium called FL31, which was selected for its antimicrobial activity against the pathogenic bacterium Listeria monocytogenes, was identified as Enterococcus faecium and noted to produce an antibacterial proteinaceous substance (BacFL31). The active peptide from the cell-free supernatant of E. faecium FL31 was purified in four steps and the results revealed a single band with an estimated molecular mass of approximately 3.5 kDa. The N-terminal amino acid sequence of the purified BacFL31 "GLEESXGHXGQXGPXGPXGAXGP" (X = hydroxyproline) showed the presence of six hydroxyproline residues. It displayed a bactericidal mode of action against L. monocytogenes. Its application at 400 AU/g was also noted to constitute an effective approach for preventing the contamination and growth of the pathogenic bacterium L. monocytogenes during the storage of minced beef meat at 4 °C.
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Advanced bone age in a girl with Wiedemann-Steiner syndrome and an exonic deletion in KMT2A (MLL).
Am. J. Med. Genet. A
PUBLISHED: 01-31-2014
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Recognition of the gene implicated in a Mendelian disorder subsequently leads to an expansion of potential phenotypes associated with mutations in that gene as patients with features beyond the core phenotype are identified by sequencing. Here, we present a young girl with developmental delay, short stature despite a markedly advanced bone age, hypertrichosis without elbow hair, renal anomalies, and dysmorphic facial features, found to have a heterozygous, de novo, intragenic deletion encompassing exons 2-10 of the KMT2A (MLL) gene detected by whole exome sequencing. Heterozygous mutations in this gene were recently demonstrated to cause Wiedemann-Steiner syndrome (OMIM 605130). Importantly, retrospective analysis of this patient's chromosomal microarray revealed decreased copy number of two probes corresponding to exons 2 and 9 of the KMT2A gene, though this result was not reported by the testing laboratory in keeping with standard protocols for reportable size cutoffs for array comparative genomic hybridization. This patient expands the clinical phenotype associated with mutations in KMT2A to include variable patterns of hypertrichosis and a significantly advanced bone age with premature eruption of the secondary dentition despite her growth retardation. This patient also represents the first report of Wiedemann-Steiner syndrome due to an exonic deletion, supporting haploinsufficiency as a causative mechanism. Our patient also illustrates the need for sensitive guidelines for the reporting of chromosomal microarray findings that are below traditional reporting size cutoffs, but that impact exons or other genomic regions of known function.
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Prevalence, identification by a DNA microarray-based assay of human and food isolates Listeria spp. from Tunisia.
Pathol. Biol.
PUBLISHED: 01-23-2014
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We aimed at evaluating the prevalence of Listeria species isolated from food samples and characterizing food and human cases isolates.
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Characterization of the bacteriocin BacJ1 and its effectiveness for the inactivation of Salmonella typhimurium during turkey escalope storage.
Food Chem
PUBLISHED: 01-22-2014
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During a screening programme for bacteriocin producers, a new lactic acid bacterium called J1, isolated from chicken gizzard, was noted to produce a bacteriocin (BacJ1) that inhibited Gram-positive and Gram-negative food-borne pathogens, especially Salmonella typhimurium, and it was, therefore, selected for identification and further study. The results, from 16S rRNA gene nucleotide sequencing (1583 pb accession no HE861352) and phylogenetic analysis, suggested that the new isolate be assigned as Weissella paramesenteroides J1. BacJ1 was purified from the culture supernatant of the J1 strain using heat treatment (15 min at 90 °C), 80% ammonium sulfate precipitation, and gel filtration (Sephadex G25). MALDI-TOF analyses revealed that BacJ1 had an exact molecular mass of 1881.036 Da. The analysis of the N-terminal sequence (GPAGPFGKLY) of this active peptide revealed no significant similarity to currently available antimicrobial peptides. The addition of pre-purified BacJ1, at a final concentration of 400 AU per gramme, may open new promising opportunities for the prevention of contamination from and growth of pathogenic bacteria, particularly S. typhimurium, during turkey escalope storage at 4 °C.
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Kaposis sarcoma with HHV8 infection and ANCA-associated vasculitis in a hemodialysis patient.
Saudi J Kidney Dis Transpl
PUBLISHED: 11-16-2013
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The association between Kaposis sarcoma (KS) and human herpes virus eight (HHV-8) infection is rarely reported in hemodialysis (HD) patients. We report here the rare association of KS, HHV-8 and hepatitis C virus (HCV) infection as well as syphilis in a HD patient. We report the case of a 72-year-old woman who presented with microscopic polyangiitis with alveolar hemorrhage and pauci-immune necrosing and crescentic glomerulonephritis as well as renal failure requiring HD. Biological tests showed positive HCV and syphilis tests. The patient was treated by HD and intravenous pulse, followed by oral corticosteroids and six cyclophosphamide monthly pulses with remission of the alveolar hemorrhage, but without renal functional recovery as the patient remained HD dependent. Five months after the first treatment administration, she developed extensive purpuric lesions on her lower limbs, abdomen face and neck. A skin biopsy showed KS. The HHV-8 test was positive, with positive polymerase chain reaction-HHV8 in the serum and skin. After immunosuppression withdrawal, the KS skin lesions regressed rapidly without relapse after 12 months of follow-up, but alveolar hemorrhage relapsed after 16 months of follow-up. Our case showed that the immunosuppressed state related to multiple factors such as aging, vasculitis, HHV-8, HCV, syphilis, immunosuppressive therapy and HD may all have contributed to the development of KS in our patient.
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Trend of plasmid-mediated quinolone resistance genes at the Childrens Hospital in Tunisia.
J. Med. Microbiol.
PUBLISHED: 11-05-2013
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The prevalence of plasmid-mediated quinolone resistance (PMQR) genes (qnr, aac(6) Ib-cr and qepA) was sought among Enterobacteriaceae strains obtained from the Childrens Hospital of Tunis (Tunisia). Nonduplicate isolates (n= 278) with resistance to extended-spectrum cephalosporins and collected in 2003, 2007, 2008 and 2009 were screened for qnr genes. Forty (14.4%) isolates were qnr positive and were then screened for the presence of aac(6)-Ib-cr and qepA genes. qnrB was detected in 21 Klebsiella pneumoniae, 11 Escherichia coli and in 6 Enterobacter cloacae isolates. Sequence analysis of the qnrB amplicons revealed variants including 24 qnrB1, 11 qnrB2, and 3 qnrB6. qnrS (qnrS1 allele) was detected only in K. pneumoniae isolates, either alone (two isolates) or with qnrB gene (one isolate). qnrA, qnrC and qnrD genes were not found in any of the 278 isolates. No qnr-positive isolates carried qepA gene. Pyrosequencing results showed that aac(6)-Ib-cr, a variant of aac(6)-Ib gene, was present in 31 qnr-positive isolates (21 K. pneumoniae isolates, 7 E. coli isolates, and 3 E. cloacae isolates). aac(6)-Ib was also found either alone (two isolates) or in association with aac(6)-Ib-cr (one isolate). Of the forty qnr-positive isolates, 92.5%, 82.5%, 57.5%, 85%, and 82.5% were nonsusceptible to nalidixic acid, ciprofloxacin, levofloxacin, ofloxacin, and norfloxacin, respectively, and all were ESBL producers. Random amplified polymorphic DNA-PCR typing of these isolates showed 16, 8, and 5 different genotypes in K. pneumoniae, E. coli, and E. cloacae isolates, respectively. Our study highlights the high prevalence of qnr in association with aac(6)-Ib-cr among Enterobacteriaceae isolates even from children who are patients not overtreated with quinolones.
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Percutaneous closure of Ostium secundum atrial septal Defect using amplatzer Occlusion Device.
Tunis Med
PUBLISHED: 09-07-2013
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aim: To report our clinical experience with transcatheter closure of ostium secundum atrial septal defects (OS ASDs) using Amplatzer septal occluder. methods: Its a retrospective study conducted between October 2005 and April 2010 and involving 34 patients. The procedures were conducted in the hemodynamic laboratory under general anesthesia with transthoracic (TTE) and transoesophageal echocardiographic (TEE) monitoring. Clinical and echocardiography assessments of the patients were conducted within 24 hours post procedure and several months after the procedure. results: From the 34 patients, 28 (82%) were females. The middle age was 27.5 years. The mean ASD diameter was 19.4 mm by TTE; 18.1 mm [12-38] by TEE, and 23.4 by angiography. The average size of the implanted devices was 23.2 mm ranging from 10 to 34 mm.The final success rate of the procedure was 90.9% (30/33). One patient was excluded from transcatheter occlusion and three patients (8,6%) had complications including two prosthesis migrations and one large residual shunting. A total of 4 patients (11,7%) underwent surgery. No major complication (thromboembolic events, obstruction of intracardiac structures, cardiac perforation, device embolization and endocarditis) or death has occurred during follow-up and all devices were securely anchored without any persistent residual shunts. Conclusion: Compared to previous data of the literature, percutaneous closure of OS ASDs using Amplatzer device appears safe and effective according to our experience of the cardiology department of Hedi Chaker Hospital.
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Alveolar hemorrhage and kidney disease: characteristics and therapy.
Saudi J Kidney Dis Transpl
PUBLISHED: 07-03-2013
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Anti-neutrophil cytoplasmic antibody-associated vasculitis and Goodpastures glomerular basement membrane disease are the most common causes of diffuse alveolar hemorrhage, a life-threatening disease. Systemic lupus erythematosus and the antiphospholipid syndrome are also causes of alveolar hemorrhage. We retrospectively reviewed 15 cases of diffuse alveolar hemorrhage (DAH) associated with renal diseases. Diagnosis of DAH was based on the presence of bloody bronchoalveolar lavage fluid. There were three men and 12 women, with a mean age of 50.5 years (extremes: 24-74 years). Proteinuria and hematuria were observed, respectively, in 15 and 14 cases. Six patients revealed arterial hypertension. Crescentic glomerulonephritis was diagnosed with kidney biopsies in ten cases. The etiology of renal disease was microscopic polyangiitis (MPA) in seven cases, Wegener disease in four cases, systemic lupus erythematous in one case, cryoglobulinemia in one case, myeloma in one case and propyl-thiouracil-induced MPA in one case. Hemoptysis occurred in 14 cases. The mean serum level of hemoglobin was 7.1 g/dL (5.1-10 g/dL). The mean serum creatinine concentration was 7.07 mg/dL (2.4-13.7 mg/dL). Gas exchange was severely compromised, with an oxygenation index <80 mmHg in 14 patients and <60 mmHg in seven patients. Bronchoalveolar lavage was performed in 11 cases, and had positive findings for hemorrhage in all. Methylprednisolone pulses and cyclophosphamide were used in 14 patients. Plasmapheresis was performed in three cases. One patient received cycles of Dexamethasome-Melphalan. Three patients died as a result of DAH. The mortality rate in our study was 20%.
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Antepartum detection of macrosomic fetus: the effect of misdiagnosis.
Tunis Med
PUBLISHED: 05-16-2013
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To determine the effect of misdiagnosis of macrosomia on maternal and perinatal outcomes.
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In Vitro Antiproliferative Effect of Arthrocnemum indicum Extracts on Caco-2 Cancer Cells through Cell Cycle Control and Related Phenol LC-TOF-MS Identification.
Evid Based Complement Alternat Med
PUBLISHED: 05-08-2013
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This study aimed to determinate phenolic contents and antioxidant activities of the halophyte Arthrocnemum indicum shoot extracts. Moreover, the anticancer effect of this plant on human colon cancer cells and the likely underlying mechanisms were also investigated, and the major phenols were identified by LC-ESI-TOF-MS. Results showed that shoot extracts had an antiproliferative effect of about 55% as compared to the control and were characterised by substantial total polyphenol content (19?mg?GAE/g DW) and high antioxidant activity (IC50 = 40? ? g/mL for DPPH test). DAPI staining revealed that these extracts decrease DNA synthesis and reduce the proliferation of Caco-2 cells which were stopped at the G2/M phase. The changes in the cell-cycle-associated proteins (cyclin B1, p38, Erk1/2, Chk1, and Chk2) correlate with the changes in cell cycle distribution. Eight phenolic compounds were also identified. In conclusion, A. indicum showed interesting antioxidant capacities associated with a significant antiproliferative effect explained by a cell cycle blocking at the G2/M phase. Taken together, these data suggest that A. indicum could be a promising candidate species as a source of anticancer molecules.
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Allelic polymorphisms of human platelets-specific alloantigens in South Tunisian population.
Hematology
PUBLISHED: 04-18-2013
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Human platelet-specific alloantigens (HPA) are polymorphic epitopes which vary among ethnic groups.
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Anticancer effect of Tamarix gallica extracts on human colon cancer cells involves Erk1/2 and p38 action on G2/M cell cycle arrest.
Cytotechnology
PUBLISHED: 04-10-2013
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Taking into account that oxidative stress is among the factors causing cancer-related death; chemoprevention which consists in using antioxidant substances such as phenolics could prevent cancer formation and progression. In the present study, phenolic contents and antioxidant activities of methanolic extracts from the halophyte Tamarix gallica shoots were determined. Moreover, the anticancer effect of this species on human colon cancer cells and the likely underlying mechanisms were also investigated. Shoot extracts showed an appreciable total phenolic content (85 mg GAE/g DW) and a high antioxidant activity (IC50 = 3.3 ?g/ml for DPPH test). At 50 and 100 ?g/ml, shoot, leaf, and flower extracts significantly inhibited Caco-2 cell growth. For instance, almost all plant part extracts inhibited cell growth by 62 % at the concentration 100 ?g/ml. DAPI staining results revealed that these extracts decrease DNA synthesis and confirm their effect on Caco-2 cells proliferation, principally at 100 ?g/ml. More importantly, cell mitosis was arrested at G2/M phase. The changes in the cell-cycle-associated proteins (cyclin B1, p38, Erk1/2, Chk1, and Chk2) are correlated with the changes in cell cycle distribution. Taken together, our data suggest that T. gallica is a promising candidate species to be used as a source of anticancer biomolecules.
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Phytodesalination of a moderately-salt-affected soil by Sulla carnosa.
Int J Phytoremediation
PUBLISHED: 03-16-2013
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The aim of this investigation was to evaluate the ability of the indifferent halophyte Sulla carnosa Desf. to desalinize a moderately-salt-affected soil. Seeds were sown on a fertile soil added or not with 1.5 g NaCl. kg(-1). Analogous treatments without plantation (control and salinized) were also used. Plant culture was performed under greenhouse conditions in non-perforated pots containing 10 kg soil each and irrigated with non-saline tap water. After 80 days of treatment, shoots were harvested. Soil samples were also collected after division of soil column in each pot into two horizons. Our results showed that salt addition increased electrical conductivity of saturation paste extract (ECe)from 3.3 to 8.4 dS. m(-1) and soluble sodium concentration from 0.32 to 1.15 g. kg(-1) soil in the upper horizon. In the lower horizon however, Na+ concentration was quasi-constant and then ECe was less increased. Plant culture inversed this pattern of sodium accumulation and salinity. Its productivity and phytodesalination capacity in 80 days were 5.0 t DW. ha(-1) and 0.3 t Na+. ha(-1) (24% of the added quantity), respectively. Interestingly, sodium dilution within biomass (41.5-45.6 mg. g(-1) DW) and the non-altered nutrition make this plant suitable for forage as second use after phytodesalination.
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Effects of the halophytes Tecticornia indica and Suaeda fruticosa on soil enzyme activities in a Mediterranean Sabkha.
Int J Phytoremediation
PUBLISHED: 03-16-2013
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In the present work, we studied the effectiveness of the predominant halophytes of Soliman sabkha (Tecticornia indica and Suaeda fruticosa) to promote soil biological activities and ecosystem productivity. Soil Arylsulphatese ARY, beta-glucosidase beta-GLU, phosphatase PHO, invertase INV, urease URE, and dehydogenase DES activities in Extra- and Intra-tuft halophytes and plant productivity were assessed. Results revealed a high increase of microbial community and ARY, beta-GLU, PHO, INV URE and DES activities (+298%, +400%, +800%, +350%, +320%, +25% and +759%, respectively) in Intra-tuft rhizosphere as compared to Extra-tuft one, which is likely due to the significant decrease of salinity in the rhizosphere of Tecticornia indica and Suaeda fruticosa. Both perennial plants exhibited high productivities (7.4 t dry weight ha(-1) and 2.2 t dry weight ha(-1), respectively) and Na+-hyperaccumulating capacities (0.75 t Na+ ha(-1) and 0.22 t Na+ ha(-1), respectively), reducing salt constraint and favouring soil fertility. This constitutes a promising alternative to enhance productivity in such a salt-affected biotope by offering suitable microhabitat for annual glycophytes.
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Computational assembly of polymorphic amyloid fibrils reveals stable aggregates.
Biophys. J.
PUBLISHED: 02-28-2013
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Amyloid proteins aggregate into polymorphic fibrils that damage tissues of the brain, nerves, and heart. Experimental and computational studies have examined the structural basis and the nucleation of short fibrils, but the ability to predict and precisely quantify the stability of larger aggregates has remained elusive. We established a complete classification of fibril shapes and developed a tool called CreateFibril to build such complex, polymorphic, modular structures automatically. We applied stability landscapes, a technique we developed to reveal reliable fibril structural parameters, to assess fibril stability. CreateFibril constructed HET-s, A?, and amylin fibrils up to 17 nm in length, and utilized a novel dipolar solvent model that captured the effect of dipole-dipole interactions between water and very large molecular systems to assess their aqueous stability. Our results validate experimental data for HET-s and A?, and suggest novel (to our knowledge) findings for amylin. In particular, we predicted the correct structural parameters (rotation angles, packing distances, hydrogen bond lengths, and helical pitches) for the one and three predominant HET-s protofilaments. We reveal and structurally characterize all known A? polymorphic fibrils, including structures recently classified as wrapped fibrils. Finally, we elucidate the predominant amylin fibrils and assert that native amylin is more stable than its amyloid form. CreateFibril and a database of all stable polymorphic fibril models we tested, along with their structural energy landscapes, are available at http://amyloid.cs.mcgill.ca.
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Chemical composition, techno-functional and sensory properties and effects of three dietary fibers on the quality characteristics of Tunisian beef sausage.
Meat Sci.
PUBLISHED: 02-26-2013
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This study determined the effects of three dietary fibers namely, VITACEL LC200 powdered cellulose (LC200), barley beta-glucan concentrate (BBC), and VITACEL KF500 potato fiber (KF500), on the techno-functional and sensory properties and quality characteristics of Tunisian beef sausage. The findings revealed interesting functional properties for LC200 fiber. This fiber displayed high water binding capacity (WBC) and oil binding capacity (OBC), values of 16.2 g/g and 10.2 g/g, respectively, which are higher than reported for most fruit and vegetable fiber concentrates. The application of LC200 improved the masticability and elasticity of beef sausage formulations and minimized their hardness and production costs without negatively affecting their sensory properties. Overall, the findings demonstrate the potential functional and economic utility of LC200 fiber as a promising source of dietary fiber.
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Lupenone from Erica multiflora leaf extract stimulates melanogenesis in B16 murine melanoma cells through the inhibition of ERK1/2 activation.
Planta Med.
PUBLISHED: 02-13-2013
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Hypopigmentation diseases are usually managed using UVB light which increases the patients risk for skin cancer. Here, we evaluated the melanogenesis stimulatory effects of leaf extracts of Erica multiflora, a medicinal plant from the Mediterranean region, and its active component, lup-20(29)-en-3-one, as possible therapeutic agents to address hypopigmentation disorders. B16 murine melanoma cells were treated with E. multiflora extracts or its active component lupenone to evaluate their effects on melanin biosynthesis. The mechanism underlying the observed effects was also determined. Bioactivity-guided fractionation of fifteen ethyl acetate fractions identified fraction 2 to have melanogenesis stimulatory effects due to its ability to decrease mitogen-activated protein kinase phosphorylated extracellular signal-regulated kinases 1 and 2 activation. Preparative TLC of ethyl acetate fraction 2 revealed the presence of lup-20(29)-en-3-one as the major bioactive component. B16 cells treated with lup-20(29)-en-3-one increased melanin content without cytotoxicity. To determine the mechanism for the observed effects of lup-20(29)-en-3-one, the tyrosinase enzyme activity, the tyrosinase protein expression, and the activation of phosphorylated extracellular signal-regulated kinases 1 and 2 were determined. In addition, the expression of the tyrosinase mRNA was quantified using real-time PCR. Results showed that lup-20(29)-en-3-one has no effect on the tyrosinase enzyme activity but can increase tyrosinase expression at both the transcriptional and translational levels. The increase in the tyrosinase mRNA expression was most likely due to the inhibited mitogen-activated protein kinase phosphorylated extracellular signal-regulated kinases 1 and 2 activation. We report for the first time that E. multiflora ethyl acetate extract and its active compound lup-20(29)-en-3-one stimulate melanogenesis by increasing the tyrosinase enzyme expression via mitogen-activated protein kinase phosphorylated extracellular signal-regulated kinases 1 and 2 phosphorylation inhibition, making it a possible treatment for hypopigmentation diseases.
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DNA variant databases improve test accuracy and phenotype prediction in Alport syndrome.
Pediatr. Nephrol.
PUBLISHED: 01-03-2013
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X-linked Alport syndrome is a form of progressive renal failure caused by pathogenic variants in the COL4A5 gene. More than 700 variants have been described and a further 400 are estimated to be known to individual laboratories but are unpublished. The major genetic testing laboratories for X-linked Alport syndrome worldwide have established a Web-based database for published and unpublished COL4A5 variants ( https://grenada.lumc.nl/LOVD2/COL4A/home.php?select_db=COL4A5 ). This conforms with the recommendations of the Human Variome Project: it uses the Leiden Open Variation Database (LOVD) format, describes variants according to the human reference sequence with standardized nomenclature, indicates likely pathogenicity and associated clinical features, and credits the submitting laboratory. The database includes non-pathogenic and recurrent variants, and is linked to another COL4A5 mutation database and relevant bioinformatics sites. Access is free. Increasing the number of COL4A5 variants in the public domain helps patients, diagnostic laboratories, clinicians, and researchers. The database improves the accuracy and efficiency of genetic testing because its variants are already categorized for pathogenicity. The description of further COL4A5 variants and clinical associations will improve our ability to predict phenotype and our understanding of collagen IV biochemistry. The database for X-linked Alport syndrome represents a model for databases in other inherited renal diseases.
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Characterization of novel RS1 exonic deletions in juvenile X-linked retinoschisis.
Mol. Vis.
PUBLISHED: 01-01-2013
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X-linked juvenile retinoschisis (XLRS) is a vitreoretinal dystrophy characterized by schisis (splitting) of the inner layers of the neuroretina. Mutations within the retinoschisis (RS1) gene are responsible for this disease. The mutation spectrum consists of amino acid substitutions, splice site variations, small indels, and larger genomic deletions. Clinically, genomic deletions are rarely reported. Here, we characterize two novel full exonic deletions: one encompassing exon 1 and the other spanning exons 4-5 of the RS1 gene. We also report the clinical findings in these patients with XLRS with two different exonic deletions.
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Change of diet, plasma lipids, lipoproteins, and fatty acids during Ramadan: a controversial association of the considered Ramadan model with atherosclerosis risk.
J Health Popul Nutr
PUBLISHED: 11-24-2011
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Different Islamic populations have different alimentary habits, notably during Ramadan. The paper reports the change of diet, lipids, and lipoproteins produced during Ramadan in one Tunisian population. During Ramadan, the study subjects consumed more proteins, cholesterol, vitamin E (p<0.01), and polyunsaturated fatty acids (p<0.05). At the same time, they exhibited an increase in total cholesterol, low-density lipoprotein-cholesterol (p<0.01) and apoprotein B (p<0.05) and a decrease in the ratio of apoprotein AI to apoprotein B (p<0.01). All assayed saturated fatty acids were unaffected by Ramadan fasting while three unsaturated fatty acids (C18:1cis9, C18:2n-6, and C30:4n-6) increased significantly. A return to the habitual diet for a four-week period was not sufficient to restore the pre-fasting patterns. For the study subjects, Ramadan was clearly associated with a change of diet and biochemical profile but its effective impact on atherosclerosis risk was unclear, perhaps, because other non-alimentary changes ought to be considered too. Future studies considering the no-alimentary factors, such as sleep and physical activity, would be useful to clarify the contribution of dietary change in the observed modification of biological profile.
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The diagnosis of pertussis: which method to choose?
Crit. Rev. Microbiol.
PUBLISHED: 11-21-2011
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Despite the introduction of routine vaccination against pertussis for more than a half century, leading to a drastic decline in the number of reported cases, pertussis continues to be an important respiratory disease afflicting unvaccinated infants and previously vaccinated children as well as adults in whom immunity has waned. The diagnosis of pertussis is challenging and accurate laboratory identification of Bordetella infections remains problematic. Common laboratory diagnostic methods used for pertussis diagnosis include culture, direct-fluorescent-antibody testing (DFA), serology and polymerase chain reaction (PCR). Culture of Bordetella pertussis is highly specific but fastidious and has limited sensitivity. DFA provides a much more rapid result, but has the disadvantage of poor sensitivity and specificity. Serology is not useful in infants. In older persons, it is hampered by the limitations of paired sera and it provides mainly a retrospective diagnosis. Such limitations of conventional diagnosis testing have led to the development of PCR assays. Notwithstanding its lack of standardization, PCR has been found to be more sensitive and more specific than other methods. In this report, we aimed to review current knowledge about the available diagnostic methods and tests that accurately diagnose pertussis.
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Immunolocalization of H(+)-ATPase and IRT1 enzymes in N(2)-fixing common bean nodules subjected to iron deficiency.
J. Plant Physiol.
PUBLISHED: 06-22-2011
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The demand for iron in leguminous plants increases during symbiosis, as the metal is utilised for the synthesis of various Fe-containing proteins in both plant and bacteroids. However, the acquisition of this micronutrient is problematic due to its low bioavailability at physiological pH under aerobic conditions. Induction of root Fe(III)-reductase activity is necessary for Fe uptake and can be coupled to the rhizosphere acidification capacity linked to the H(+)-ATPase activity. Fe uptake is related to the expression of a Fe(2+) transporter (IRT1). In order to verify the possible role of nodules in the acquisition of Fe directly from the soil solution, the localization of H(+)-ATPase and IRT1 was carried out in common bean nodules by immuno-histochemical analysis. The results showed that these proteins were particularly abundant in the central nitrogen-fixing zone of nodules, around the periphery of infected and uninfected cells as well as in the vascular bundle of control nodules. Under Fe deficiency an over-accumulation of H(+)-ATPase and IRT1 proteins was observed especially around the cortex cells of nodules. The results obtained in this study suggest that the increase in these proteins is differentially localized in nodules of Fe-deficient plants when compared to the Fe-sufficient condition and cast new light on the possible involvement of nodules in the direct acquisition of Fe from the nutrient solution.
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[Factor V deficiency and pregnancy: a case report].
Ann. Biol. Clin. (Paris)
PUBLISHED: 06-11-2011
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The factor V deficiency is a very rare hereditary disease of the coagulation, which is accompanied by a high hemorrhagic risk in the event of delivery and in the post-partum. We report the case of a woman having a factor V deficiency which had a pregnancy, and which gave birth by Cesarean, as replacement therapy we proposed the transfusion of 20?mL/kg of fresh frozen plasma before surgery and of 5?mL/kg by 12?h during 7 days in post-partum, this attitude allowed to avoid the hemorrhagic complications.
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[Sweet syndrome revealing leukemia].
Arch Pediatr
PUBLISHED: 06-10-2011
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Sweet syndrome is a neutrophilic dermatosis that can lead to various inflammatory and neoplastic pathologies. We report a case of Sweet syndrome revealing acute leukemia at a 13-year-old girl, who had no history of illness. The diagnosis was made in spite of atypical skin lesions and was confirmed by the skin biopsy and the bone marrow examination. In spite of corticosteroid therapy and chemotherapy, the patient died. Sweet syndromes diagnosis requires an exhaustive etiologic survey. If there is no evidence of underlying disease, patients must be regularly monitored.
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The new health legacy: when pertussis becomes a heritage transmitted from mothers to infants.
J. Med. Microbiol.
PUBLISHED: 06-09-2011
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Despite high vaccination coverage rates, there has been a gradual increase in reported pertussis cases. Although whooping cough affects all ages, young infants continue to suffer the greatest pertussis disease burden. Adolescents and adults are the primary source of infection for young babies. In this paper, we report two cases involving the likely transmission of pertussis from mothers to infants in Tunisia.
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Physiological and anatomical adaptations induced by flooding in Cotula coronopifolia.
Acta. Biol. Hung.
PUBLISHED: 05-11-2011
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Cotula coronopifolia is a wild annual Asteraceae that grows in periodically-flooded prone environments and seems highly tolerant to periodic flooding. Seedlings of about 15 cm were collected directly from the edge of Soliman sabkha (N-E Tunisia, semi-arid stage) and grown under greenhouse conditions. Two treatments were considered: drainage and flooding. After 56 days of treatment, flooded plants showed a pronounced growth increase. This performance was essentially associated with significant increment in biomass production of both shoots and roots (about 220% of the control). The appropriate response to flooding was also characterized by the ability of the species to maintain its water status under such conditions. Neither water content nor water potential showed a significant variation as compared to those of non-flooded plants. However, transpiration rate decreased slightly but significantly in flooded plants (from 0.86 to 0.64 mmol H2O m-2 s-1). Na+ and K+ concentrations were practically maintained under waterlogging conditions, except a significant increase of Na+ content in roots of flooded plants (157% of the control). These responses were concomitant with maintenance of photosynthetic rate. However, the contents of chlorophylls a and b increased to 167% and 295%, respectively. It seems that the enhancement in these photosynthetic pigments together with a significant improvement in water use efficiency (from 4.66 to 6.07 mmol CO2 mol-1 H2O) allowed to the species to compensate the decrease in photosynthetic rate. At the anatomical level, this species responded to flooding by a significant development of its root aerenchyma (+63%) and an increase in the lignification of its stem xylem tissues (+37%). Based on the presented data, the plant fitness under flooding conditions was a result of dynamic readjustment of several morphological, physiological, and anatomical adaptive traits. Flood requirement together with salt tolerance are responsible for the predominance of C. coronopifolia in a large area in its natural biotope where most plants cannot tolerate interactive effects of flooding and salinity.
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Prevalence of factor V Leiden in south Tunisian blood donors.
J. Thromb. Thrombolysis
PUBLISHED: 03-25-2011
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Venous thrombosis (VT) is a common disease with multifactorial pathogenesis. Factor V Leiden mutation (G1691A) (FVL) is the most common risk factor in venous thrombosis. The prevalence of FVL varies according to geography and ethnicity. Hence, in several countries there is a difference in the frequency of this mutation between the southern, central and north. In Tunisia, no data is available about prevalence of FVL mutation by geographical origin. For this reason, we sought the prevalence of FVL mutation in blood donor of south Tunisia population. FVL has been detected by APCR-test and confirmed by PCR-RFLP and sequencing. Two hundred fifty blood donors, different in age and sex were included in this study to determine the prevalence of FVL in blood donors. FVL mutation was found in 13.6% of the studied population. Thirty-one were heterozygous and three persons were homozygous with a rate of 12.4 and 1.2%, respectively. In conclusion, FVL mutation is very common in south Tunisian population.
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Taxonomy, purification and chemical characterization of four bioactive compounds from new Streptomyces sp. TN256 strain.
World J. Microbiol. Biotechnol.
PUBLISHED: 03-08-2011
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A new actinomycete strain designated TN256, producing antimicrobial activity against pathogenic bacteria and fungi, was isolated from a Tunisian Saharan soil. Morphological and chemical studies indicated that strain TN256 belonged to the genus Streptomyces. Analysis of the 16S rDNA sequence of strain TN256 showed a similarity level ranging between 99.79 and 97.8% within Streptomyces microflavus DSM 40331(T) and Streptomyces griseorubiginosus DSM 40469(T) respectively. The comparison of its physiological characteristics showed significant differences with the nearest species. Combined analysis of the 16 S rRNA gene sequences (FN687758), fatty acids profile, and results of physiological and biochemical tests indicated that there were genotypic and phenotypic differentiations of that isolate from other Streptomyces species neighbours. These date strongly suggest that strain TN256 represents a novel species with the type strain Streptomyces TN256 (=CTM50228(T)). Experimental validation by DNA-DNA hybridization would be required for conclusive confirmation. Four active products (1-4) were isolated from the culture broth of Streptomyces TN256 using various separation and purification steps and procedures. 1: N-[2-(1H-indol-3-yl)-2 oxo-ethyl] acetamide alkaloid derivative; 2: di-(2-ethylhexyl) phthalate, a phthalate derivative; 3: 1-Nonadecene and 4: Cyclo (L: -Pro-L: -Tyr) a diketopiperazine DKP derivative. The chemical structure of these four active compounds was established on the basis of spectroscopic studies NMR and by comparing with data from the literature. According to our biological studies, we showed in this work that the pure compounds (1-4) possess antibacterial and antifungal activities.
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Microbiological profile of haematogenous osteoarticular infections in children.
Orthop Traumatol Surg Res
PUBLISHED: 03-02-2011
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Staphylococcus aureus, Kingella kingae and ?-hemolytic streptococcus are presently the most frequently identified bacteria in child haematogenous osteoarticular infection.
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Purification and structure elucidation of three naturally bioactive molecules from the new terrestrial Streptomyces sp. TN17 strain.
Nat. Prod. Res.
PUBLISHED: 02-15-2011
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Thirty litres of fermentation broth was extracted from the newly isolated Streptomyces sp. strain TN17 and various separation and purification steps led to the isolation of three pure bioactive compounds (1-3). Compound 1: cyclo (L-Leu-L-Arg), a diketopiperazine DKP derivative; 2: di-(2-ethylhexyl) phthalate, a phthalate derivative; and 3: cyclo 1-[2-(cyclopentanecarbonyl-3-phenyl-propionyl]-pyrrolidine-2-carboxylic acid (1-carbamoyl-propyl)-amide, a cyclic tetrapeptide derivative. The chemical structure of these three active compounds was established on the basis of spectroscopic studies (MS and NMR) and by comparison with data from the literature. According to our biological studies, the pure compounds (1-3) possess antibacterial and antifungal activities.
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Dual infection with Bordetella pertussis and Mycoplasma pneumoniae in three infants: case reports.
Infection
PUBLISHED: 02-04-2011
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Studying pertussis-like respiratory infections, we report the cases of three infants with evidence of both Bordetella pertussis and Mycoplasma pneumoniae. Bordetella infection was identified by the real-time polymerase chain reaction (RT-PCR) of nasopharyngeal specimens. Neither B. pertussis nor B. parapertussis were recovered on the culture of nasopharyngeal aspirates (NPAs) from any subjects. M. pneumoniae etiology was diagnosed by culture and RT-PCR. The evolution was fatal for all of the subjects. We conclude that, among patients with Bordetella infection, co-infection with another respiratory pathogen is often probable, and these mixed infections might cause a more severe form of illness, sometimes leading to death.
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Fatal subdural empyema caused by Streptococcus constellatus and Actinomyces viscosus in a child--case report.
J Microbiol Immunol Infect
PUBLISHED: 01-20-2011
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Group milleri streptococci that colonize the mouth and the upper airways are generally considered to be commensal. In combination with anaerobics, they are rarely responsible for brain abscesses in patients with certain predisposing factors. Mortality in such cases is high and complications are frequent. We present a case of fatal subdural empyema caused by Streptococcus constellatus and Actinomyces viscosus in a previously healthy 7-year-old girl.
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[The re-emergence of pertussis in Tunisia].
Med Mal Infect
PUBLISHED: 01-06-2011
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The authors had for aim to analyze pertussis epidemiology in Tunisia by studying nasopharyngeal specimens of infants hospitalized in Tunis.
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Abnormal cone structure in foveal schisis cavities in X-linked retinoschisis from mutations in exon 6 of the RS1 gene.
Invest. Ophthalmol. Vis. Sci.
PUBLISHED: 01-01-2011
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To evaluate macular cone structure in patients with X-linked retinoschisis (XLRS) caused by mutations in exon 6 of the RS1 gene.
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High-throughput retina-array for screening 93 genes involved in inherited retinal dystrophy.
Invest. Ophthalmol. Vis. Sci.
PUBLISHED: 01-01-2011
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Retinal dystrophy (RD) is a broad group of hereditary disorders with heterogeneous genotypes and phenotypes. Current available genetic testing for these diseases is complicated, time consuming, and expensive. This study was conducted to develop and apply a microarray-based, high-throughput resequencing system to detect sequence alterations in genes related to inherited RD.
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Molecular analysis of Bardet-Biedl syndrome families: report of 21 novel mutations in 10 genes.
Invest. Ophthalmol. Vis. Sci.
PUBLISHED: 01-01-2011
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Bardet-Biedl syndrome (BBS) is genetically heterogeneous with 15 BBS genes currently identified, accounting for approximately 70% of cases. The aim of our study was to define further the spectrum of BBS mutations in a cohort of 44 European-derived American, 8 Tunisian, 1 Arabic, and 2 Pakistani families (55 families in total) with BBS.
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Nutrient uptake and management under saline conditions in the xerohalophyte: Tecticornia indica (Willd.) subsp. indica.
Acta. Biol. Hung.
PUBLISHED: 11-30-2010
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In the present investigation, we studied uptake and management of the major cations in the xerohalophyte, Tecticornia indica (Willd.) subsp. indica as subjected to salinity. Plants were grown under greenhouse conditions at various salinity levels (0, 100, 200 and 400 mM NaCl) over 110 days. At harvest, they were separated into shoots and roots then analyzed for water contents, dry weights (DW), and Na+, K+, Ca²+, and Mg²+ contents. Plants showed a growth optimum at 200 mM NaCl and much better tissue hydration under saline than non-saline conditions. At this salt concentration (200 mM NaCl), shoot Na+ content reached its highest value (7.9 mmol · g-?¹ DW). In spite of such stressful conditions, salt-treated plants maintained adequate K+, Ca²+, and Mg²+ status even under severe saline conditions. This was mainly due to their aptitude to selectively acquire these essential cations and efficiently use them for biomass production.
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Differential response to salinity and water deficit stress in Polypogon monspeliensis (L.) Desf. provenances during germination.
Plant Biol (Stuttg)
PUBLISHED: 11-03-2010
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The effects of provenance, salinity (0, 100, 200, 300 and 400 mm NaCl) and water deficit (0, -0.6, -1.1, -1.6 and -2.1 MPa mannitol solutions) on germination success of Polypogon monspeliensis were investigated. Eight Tunisian provenances from different bioclimatic origins were considered. Seed mass varied significantly between populations. Germination percentage was significantly affected by provenance, salinity and their interaction. Even at 300 mm NaCl, germination percentage of Tabarka, Kelbia and Kebili ranged from ca. 60% to ca. 85%, whereas Monastir, Gabes and El Haouaria succeeded in germinating in 200 mm NaCl. The 300 mm NaCl treatment highly reduced germination of Monastir and El Haouaria, and inhibited that of Gabes. Soliman and El Jem were the least salt-tolerant provenances. The severity of water deficit impact on seed germination was also provenance-dependent, especially at osmotic potentials of -1.1 to -1.6 MPa. At -1.6 MPa, germination percentage of Tabarka, Monastir and Kebili was close to 80%, while that of Gabes, El Jem and Kelbia was 0%, 5% and 20%, respectively. Regardless of provenance, germination was strongly impaired at -2.1 MPa. The variability of stress tolerance in P. monspeliensis could be of practical significance in programmes aimed at restoring arid and salt-affected lands since it allows use of provenances that germinate and establish successfully under unfavourable conditions prevailing in such zones.
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Molecular analysis of community-acquired methicillin-susceptible and resistant Staphylococcus aureus isolates recovered from bacteraemic and osteomyelitis infections in children from Tunisia.
Clin. Microbiol. Infect.
PUBLISHED: 10-26-2010
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Thirty-six children (27 boys, nine girls) that fulfilled CDC criteria for community-acquired infections were diagnosed with bacteraemia and/or osteomyelitis caused by Staphylococcus aureus during an 18-month period (2006-2008). Antibiotic susceptibility was determined by an agar dilution method. SCCmec type, carriage of pvl genes, agr type and spa-typing were determined using specific PCR protocols. Clonal relatedness was examined by pulsed field gel electrophoresis-SmaI and mutilocus sequence typing techniques. From the 36 isolates, eight (22%) corresponded to methicillin-resistant Staphylococcus aureus (MRSA) -t044/042-CC80/CC5-IVc-pvl(+) -agrIII/II. The highest genetic diversity was observed among the 28 community-acquired methicillin-susceptible S. aureus (CA-MSSA) isolates: 22 spa-variants that also grouped by multilocus sequence typing in CC1, CC5, CC6, CC8, CC30, CC80, CC97 and the singletons ST464, ST1467, ST1468 and ST1469. The pvl genes were detected in all eight CA-MRSA isolates and in eight CA-MSSA isolates (28%), being significantly more frequent among isolates causing osteoarticular infection (11 of 12, 92%) than in the bacteraemic isolates (six of 24, 25%). Based on patients age, three groups were considered: newborns, infants and children. Bacteraemia was diagnosed in all newborns and infants, whereas in 42% of the children group osteomyelitis was the unique presentation. In most cases, the portal of entry was either the skin or unknown. In general, favourable outcome was observed, except in four cases-three of whom had severe complications and one died. In summary, we analysed the epidemiological and genetic background of community-acquired staphylococcal strains causing bacteraemic and/or osteomyelitis infections in children from Tunisia, describing three new sequence types and one novel spa type.
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[Malignant pertussis: an underdiagnosed illness].
Med Trop (Mars)
PUBLISHED: 08-26-2010
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Malignant pertussis is a rare life-threatening illness characterized by severe respiratory failure, severe leukocytosis, and pulmonary hypertension. The purpose of this study was to determine the prevalence of malignant pertussis in infants admitted to a pediatric intensive care unit (PICU) for severe acute respiratory failure associated with severe leukocytosis.
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[Iatrogenic meningitis after diagnosis lumbar puncture: 3 cases reports in the paediatric Childrens Hospital of Tunis].
Bull Soc Pathol Exot
PUBLISHED: 06-29-2010
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We have collected cases of iatrogenic meningitis managed in the Childrens Hospital of Tunis, between January 1998 and December 2006. Clinical information about each patient were collected, all bacterial samples were investigated in the microbiology laboratory of the hospital. Bacterial isolates were identified according to conventional criteria. In the interval under study, we recorded three cases of iatrogenic meningitis after lumbar puncture. Two cases occurred in newborn admitted for suspicion of neonatal infection and one in a 2-month-old infant admitted for exploration of hyperpyretic convulsion. In all patients, the initial cerebrospinal fluid was normal. All patients developed symptoms of acute meningitis within 72 hours after lumbar puncture; the second cerebrospinal fluid was, then, typical for purulent meningitis. The causal agents isolated in the three cases were Klebsiella pneumoniae, Enterobacter cloacae, and Serratia marcescens, all resistant to beta-lactams by extended spectrum beta-lactamase production. The use of quinolones was required in all cases. Different complications were recorded: hydrocephalus and brain abscess in one case, respiratory and hemodynamic failure managed in the intensive care unit in the second, and brain hygroma in the third case. This study shows high morbidity of iatrogenic meningitis. Simple aseptic precautions undertaken before the procedure of lumbar puncture can prevent such cases. The urgent need for increasing the awareness among medical personnel in hospitals of developing countries cannot be overemphasized.
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[A rare cause of pruritus in an hemodialysed patient].
Tunis Med
PUBLISHED: 06-03-2010
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Uremic pruritus is frequent in patients undergoing hemodialysis. Its multifactorial secondary in most cases to metabolic complications related to uremia.
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[Listeriosis in Tunis: seven cases reports].
Bull Soc Pathol Exot
PUBLISHED: 04-05-2010
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Listeria monocytogenesis a Gram positive facultative intracellular bacterium that can be responsible for severe infections, affecting essentially pregnant women, immunocompromised patients at the early and later stages of life. In Tunisia, invasive L. monocytogenes infections are thought to be exceptional and limited data are available about listeriosis. We reported seven cases (five newborn children and two infants) of human listeriosis that occurred in Tunis from 2000 to 2008. The newborn children were hospitalized for suspicion of maternofoetal infections. The two infants were hospitalized for fever associated with digestive signs in one case and neurological signs in the other. L. monocytogenes-was isolated from culture of cerebrospinal fluid in four cases, peripheral samples in two cases and from blood culture in one case. Isolates identification was based on conventional methods. Antimicrobial susceptibility was realized according to the recommendation of the "Comité de lantibiogramme de la Société française de microbiologie". All L. monocytogenes isolates were sensitive to amoxicillin and aminoside but resistant to 3rd generation cephalosporins. Investigations of the immune system were realized for the two infants including phenotypic analysis of peripheral blood cells by flow cytometry, lymphocyte proliferation assays, phagocytic cell functions and measurement of immunoglobulins as well as complement. All these explorations were normal for both infants. The outcome was fatal in only one case (a newborn child), and all the other patients recovered after adapted antibiotic treatment. In conclusion, our study shows that listeriosis is not exceptional in Tunis. Thus, it is necessary to know how to evoke this diagnosis, at any age, in order to establish an early and adapted antibiotic treatment and to avoid fatal outcome.
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Phytodesalination of a salt-affected soil with the halophyte Sesuvium portulacastrum L. to arrange in advance the requirements for the successful growth of a glycophytic crop.
Bioresour. Technol.
PUBLISHED: 03-18-2010
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In the present work, we studied the potential of the obligate halophyte, Sesuvium portulacastrum L., to desalinize an experimentally-salinized soil after the following criteria: (i) decrease in soil salinity and sodicity, (ii) plant biomass capacity to accumulate sodium ions, and (iii) phytodesalinized soil quality (equivalent to growth of a glycophytic test culture of Hordeum vulgare L.). The cultivation of the halophyte on the salinized soil (phytodesalination culture) led to a marked absorption of Na(+) ions by S. portulacastrum roots and their accumulation in the above-ground biomass up to 872 mg plant(-1) and 4.36 g pot(-1) (about 1 tha(-1)). The decrease in salinity and sodicity of the phytodesalinized soil significantly reduced the negative effects on growth of the test culture of H. vulgare. Furthermore, the phytodesalination enabled H. vulgare plants to keep a high water content and to develop a higher biomass with relatively high K and low Na contents.
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Sesuvium portulacastrum maintains adequate gas exchange, pigment composition, and thylakoid proteins under moderate and high salinity.
J. Plant Physiol.
PUBLISHED: 03-08-2010
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Cuttings of Sesuvium portulacastrum L. (Aizoaceae) were taken from plants cultivated under severe saline conditions. The obtained seedlings were grown on sand and irrigated with nutrient solution over 5 weeks under no (0 mM NaCl), moderate (200 mM NaCl), or high (400 mM NaCl) salinity conditions. A follow-up of gas exchange was performed weekly and pigment levels and patterns of fully expanded leaves were determined after 3 and 5 weeks of treatment. At the end of the 5-week period, immunoblot analysis of the main polypeptides of photosystem I and II was performed with the aim to investigate salt-induced variations in photosystem composition. Net CO2 assimilation rate (Pn) increased under salinity up to 3 weeks of treatment then decreased to reach the value of 0mM-treated plants at the end of the experiment. For stomatal conductance (gs) and intercellular CO2 concentration (Ci), the opposite occurred. These results were concomitant with an increase in practically all pigment levels, mainly under high salinity, with the exception of zeaxanthin. The de-epoxidation index (DEPS index) was much lower under saline than non-saline conditions in the 3rd week, indicating light stress in 0mM-treated plants. At the end of the experiment, this index showed much lower values with no significant differences between treatments, which coincided with no significant differences in gas exchange as well. Protein amounts of D1, CP47, and CP43 did not show noticeable variations with salt treatment, whereas LHCII underwent a slight but significant decrease (-15%) at the highest NaCl concentration. LHCI polypeptides were unaffected by the salt treatments, where conversely, the highest concentration induced a significant decrease in PsaA/B amount (-18%).
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Localization of potential ion transport pathways in vesicular trichome cells of Atriplex halimus L.
Protoplasma
PUBLISHED: 02-10-2010
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The secreting glandular trichomes are recognized as an efficient structure that alleviates salt effects on Atriplex halimus. They are found on buds, young green stems, and leaves. They occupy both the leaf surfaces and give them a whitish color. Their histogenesis and ultrastructure were investigated in the third young leaves. They appear in early stage of plant development and its initiation continuous until just the leaf final development state. Each trichome contains two parts; a stalk which has high electron opacity, embedded in epidermal cells, and bears a second one which is unicellular, called bladder cell and has a low electron density. The bladder cell appears as a huge vacuole and the well-reduced cytoplasm which is pushed close to the wall, contains only a few organelles. Concurrently, the use of silver chloride precipitation technique shows that, in secretion process, salt follows a symplasmatic pathway which is consolidated by the presence of numerous plasmodesmata between the stalk cell(s), and the bladder one and the neighboring mesophyll cells. In addition, according to lanthanum-tracer study, salt can be excreted apoplastically. In fact, the heavy element can be transported via endocytosis vesicles, and by Golgi, endoplasmic reticulum, and lysosome (G.E.R.L.) network toward the storage vacuoles.
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Cardiovascular risk factors in hemodialysis and peritoneal dialysis patients.
Saudi J Kidney Dis Transpl
PUBLISHED: 01-12-2010
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Cardiovascular diseases are a major cause of morbidity and mortality in patients with end-stage renal disease (ESRD). The aim of our investigation was the evaluation of an extensive cardiovascular profile in hemodialysis (HD) and peritoneal dialysis (PD) patients. We studied 74 patients with ESRD (38 males, 36 females), maintained either on chronic HD (n= 50) or chronic PD (n= 24) and age and sex matched 20 healthy subjects as controls. The lipid profile, homocysteine (Hcy) and C reactive protein (CRP) were measured. When compared to a healthy population, HD patients displayed a marked atherogenic profile, as attested by increased levels of total cholesterol (TC), triglycerides (TG), low-density lipoprotein-cholesterol (LDL-C), apolipoprotein A (Apo A), CRP, Hcy and lower concentrations of high-density lipoprotein-cholesterol (HDL-C), Apo B, albumin (ALB). A significant difference was noted concerning the rates of Apo B, HDL-C, TC, ALB and Hcy. Same biological disorders that those found at HD patients were noted in these PD patients. One also noted lower concentration in Apo A. there were a significant difference with the reference group concerning the rates of albumin, Apo A, HDL-Cl and Hcy. When compared to PD patients, HD patients had significantly decreased concentration of LDL-C. The peculiar metabolic changes observed in the present study confirm the marked tendency of patients with impaired renal function for developing cardiovascular diseases, irrespectively of the type of dialysis. We suggest including uremia-related risk factors in the panel for evaluation of cardiovascular risk in dialysis patients.
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Molecular modeling of retinoschisin with functional analysis of pathogenic mutations from human X-linked retinoschisis.
Hum. Mol. Genet.
PUBLISHED: 01-08-2010
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Gene mutations that encode retinoschisin (RS1) cause X-linked retinoschisis (XLRS), a form of juvenile macular and retinal degeneration that affects males. RS1 is an adhesive protein which is proposed to preserve the structural and functional integrity of the retina, but there is very little evidence of the mechanism by which protein changes are related to XLRS disease. Here, we report molecular modeling of the RS1 protein and consider perturbations caused by mutations found in human XLRS subjects. In 60 XLRS patients who share 27 missense mutations, we then evaluated possible correlations of the molecular modeling with retinal function as determined by the electroretinogram (ERG) a- and b-waves. The b/a-wave ratio reflects visual-signal transfer in retina. We sorted the ERG b/a-ratios by patient age and by the mutation impact on protein structure. The majority of RS1 mutations caused minimal structure perturbation and targeted the protein surface. These patients b/a-ratios were similar across younger and older subjects. Maximum structural perturbations from either the removal or insertion of cysteine residues or changes in the hydrophobic core were associated with greater difference in the b/a-ratio with age, with a significantly smaller ratio at younger ages, analogous to the ERG changes with age observed in mice with no RS1-protein expression due to a recombinant RS1-knockout gene. The molecular modeling suggests an association between the predicted structural alteration and/or damage to retinoschisin and the severity of XLRS as measured by the ERG analogous to the RS1-knockout mouse.
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Interactive effects of salinity, nitrate, light, and seed weight on the germination of the halophyte Crithmum maritimum.
Acta. Biol. Hung.
PUBLISHED: 12-18-2009
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Interaction of salinity, nitrate, light, and seed weight on the germination of Crithmum maritimum was investigated. Seeds of three size categories were germinated at 0-200 mM NaCl with either 0, 5 or 20 mM KNO 3 . Experiments were done under darkness, white light, or red light. Regardless of seed weight, germination was maximal in distilled water. Under salinity, the smallest seeds showed the highest germination percentage. Salt impact was amplified by darkness, but was mitigated by nitrate supply, red light and their combination. At the same PPFD, germination of T2 seeds was higher, when exposed to red light than under white light, suggesting that germination was more influenced by the light type than by the PPFD. As a whole, not only salinity, nutrient availability, seed weight, and light, but also their interaction may control the germination of this halophyte.
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[Use of the rapid antigen detection test in group A streptococci pharyngitis diagnosis in Tunis, Tunisia].
Bull Soc Pathol Exot
PUBLISHED: 09-11-2009
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The aims of this study were to determine the contribution of commercial rapid antigen detection test (RADT) in the rapid diagnosis of pharyngitis caused by group A streptococci. A total of 292 children with pharyngitis was included. A duplicate throat swabs was taken simultaneously from each patient. One of them was used for RADT achievement and the other for culture. When cultures were positive, a semi-quantitative evaluation was done. Throat culture and RADT were positive in 59 and 72 cases respectively. Fifty four specimens were positive simultaneously with RADT and culture and 215 specimens were negative using both methods. Eighteen specimens were positive only with RADT, 5 of them were treated by amoxicillin. Regarding to the group of patients with a negative RADT and a positive culture (5 cases), all of them had a culture evaluation at "+" or "++". Specificity and sensibility of the RADT were 92.2% and 91.5% respectively. RADT use by physicians can reduce antibiotic prescription among paediatric population. Because of the high specificity of RADT, therapeutic decisions can be made on the basis of a positive test.
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Inhibition of fungi and gram-negative bacteria by bacteriocin BacTN635 produced by Lactobacillus plantarum sp. TN635.
Appl. Biochem. Biotechnol.
PUBLISHED: 08-18-2009
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The aim of this study was to evaluate 54 lactic acid bacteria (LAB) strains isolated from meat, fermented vegetables and dairy products for their capacity to produce antimicrobial activities against several bacteria and fungi. The strain designed TN635 has been selected for advanced studies. The supernatant culture of this strain inhibits the growth of all tested pathogenic including the four Gram-negative bacteria (Salmonella enterica ATCC43972, Pseudomonas aeruginosa ATCC 49189, Hafnia sp. and Serratia sp.) and the pathogenic fungus Candida tropicalis R2 CIP203. Based on the nucleotide sequence of the 16S rRNA gene of the strain TN635 (1,540 pb accession no FN252881) and the phylogenetic analysis, we propose the assignment of our new isolate bacterium as Lactobacillus plantarum sp. TN635 strain. Its antimicrobial compound was determined as a proteinaceous substance, stable to heat and to treatment with surfactants and organic solvents. Highest antimicrobial activity was found between pH 3 and 11 with an optimum at pH = 7. The BacTN635 was purified to homogeneity by a four-step protocol involving ammonium sulfate precipitation, centrifugal microconcentrators with a 10-kDa membrane cutoff, gel filtration Sephadex G-25, and C18 reverse-phase HPLC. SDS-PAGE analysis of the purified BacTN635, revealed a single band with an estimated molecular mass of approximately 4 kDa. The maximum bacteriocin production (5,000 AU/ml) was recorded after a 16-h incubation in Man, Rogosa, and Sharpe (MRS) medium at 30 degrees C. The mode of action of the partial purified BacTN635 was identified as bactericidal against Listeria ivanovii BUG 496 and as fungistatic against C. tropicalis R2 CIP203.
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Five naturally bioactive molecules including two rhamnopyranoside derivatives isolated from the Streptomyces sp. strain TN58.
Nat. Prod. Res.
PUBLISHED: 08-08-2009
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Extraction of 25 L fermentation broth of the newly isolated Streptomyces sp. strain TN58 and various separation and purification steps led to the isolation of five bioactive metabolites, namely brevianamide F (C1), reported from a streptomycete for the first time, N(beta)-acetyltryptamine (C2), thiazolidomycin (C3), and two rhamnopyranosides (C4 and C5). These two rhamnopyranosides were produced directly, without precursor addition. The chemical structure of these five active compounds was established on the basis of (1)H, (13)C/APT and 2D NMR spectra, ESI and EI-MS data, and by comparison with data from the literature. According to the biological studies, we show in this work that the compounds C1, C2, C4 and C5 possess antimicrobial activities.
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Selection of cell death-deficient p53 mutants in Saccharomyces cerevisiae.
Yeast
PUBLISHED: 07-07-2009
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The budding yeast Saccharomyces cerevisiae is a useful system for the detection and transcriptional evaluation of mutant p53 in cancer. In previous work we showed that the overexpression of wild-type p53 induces yeast cell death on minimal medium; however, the R248W p53 mutant was completely inactive, and we suggested that ROS production is a key event in p53-induced yeast cell death. In this study we explored the effect of other p53 mutants, such as the hot-spot mutant R282W and the double mutant N268S::I332V. Unexpectedly, both mutants behaved inversely to R248W, as they completely inhibited yeast growth on minimal medium and induced ROS production. This phenotype yeast cell death on minimal medium allowed for the subsequent screening of intragenic p53-inactivating mutations. In all cases, the revertant yeast clones display a complete p53 inactivation through either gross deletion or nonsense mutations. More interestingly, missense mutations were also found: the deletion of I255 or substitution of R337G completely inactivated the p53 mutant R282W in the yeast context. Taken together, these results suggest that p53 tumour-derived mutants could be classified according to their ability to induce yeast cell death and not uniquely by their transcriptional activity on a selected target reporter gene.
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Bioactive secondary metabolites from a new terrestrial Streptomyces sp. TN262.
Appl. Biochem. Biotechnol.
PUBLISHED: 06-23-2009
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During our search for Streptomyces spp. as new producers of bioactive secondary metabolites, the ethyl acetate extract of the new terrestrial Streptomyces isolate TN262 delivered eight antimicrobially active compounds. They were identified as 1-acetyl-beta-carboline (1), tryptophol (2), cineromycin B (3), 2,3-dihydrocineromycin B (4), cyclo-(tyrosylprolyl) (5), 3-(hydroxyacetyl)-indole (6), brevianamide F (7), and cis-cyclo-(L-prolyl-L-leucyl) (8). Three further metabolites were detected in the unpolar fractions using GC-MS and tentatively assigned as benzophenone (9), N-butyl-benzenesulfonamide (10), and hexanedioic acid-bis-(2-ethylhexyl) ester (11). This last compound is known as plasticizer derivatives, but it has never been described from natural sources. In this article, we describe the identification of the new Streptomyces sp. isolate TN262 using its cultural characteristics, the nucleotide sequence of the corresponding 16S rRNA gene and the phylogenetic analysis, followed by optimization, large-scale fermentation, isolation of the bioactive constituents, and determination of their structures. The biological activity of compounds (2), (3), (4), and those of the unpolar fractions was addressed as well.
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[Beta lactam resistance and molecular markers of 157 Haemophilus influenzae isolates from infants in Tunis].
Can. J. Microbiol.
PUBLISHED: 06-02-2009
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The aim of this study was to precise the capsular type of Haemophilus influenzae, to determine its susceptibility to beta-lactam agents, and to search for an eventual clonality between the clinical strains of the pathogen. Polymerase chain reaction was carried out to confirm the capsular type and to determine the beta-lactamase type. Minimum inhibitory concentrations (MICs) of beta-lactam agents for H. influenzae were determined by the agar dilution method on Haemophilus test medium, and the strains were analyzed by pulsed-field gel electrophoresis after SmaI restriction. Among 157 strains of H. influenzae studied, 12.1% was of serotype b. Sixty-seven strains (42.7%) were resistant to amoxicillin, among which 51 were resistant through production of TEM-type beta-lactamase while 16 showed high MICs for amoxicillin, amoxicillin + clavulanic acid, and cefuroxim, which suggested a resistance by modification of penicillin-binding proteins. Among the latter strains, five were producing TEM-type beta-lactamase. Cefotaxim, cefixim, and cefpodoxim had low MICs in all cases. The pulsed-field gel electrophoresis revealed 110 pulsotypes. All H. influenzae strains, including noncapsulated strains and serotype-b encapsulated strains, had a high level of heterogeneity, with diversity indices of respectively 0.67 and 0.94.
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Null retinoschisin-protein expression from an RS1 c354del1-ins18 mutation causing progressive and severe XLRS in a cross-sectional family study.
Invest. Ophthalmol. Vis. Sci.
PUBLISHED: 05-27-2009
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To explore the retinoschisin (RS1) protein biochemical phenotype from an RS1 exon-5 deletion/insertion frame-shift mutation in a family with X-linked retinoschisis (XLRS) and describe the clinical and electrophysiological features.
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Chitosan-plasmid nanoparticle formulations for IM and SC delivery of recombinant FGF-2 and PDGF-BB or generation of antibodies.
Gene Ther.
PUBLISHED: 05-14-2009
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Growth factor therapy is an emerging treatment modality that enhances tissue vascularization, promotes healing and regeneration and can treat a variety of inflammatory diseases. Both recombinant human growth factor proteins and their gene therapy are in human clinical trials to heal chronic wounds. As platelet-derived growth factor-bb (PDGF-BB) and fibroblast growth factor-2 (FGF-2) are known to induce chemotaxis, proliferation, differentiation, and matrix synthesis, we investigated a non-viral means for gene delivery of these factors using the cationic polysaccharide chitosan. Chitosan is a polymer of glucosamine and N-acetyl-glucosamine, in which the percentage of the residues that are glucosamine is called the degree of deacetylation (DDA). The purpose of this study was to express PDGF-BB and FGF-2 genes in mice using chitosan-plasmid DNA nanoparticles for the controlled delivery of genetic material in a specific, efficient, and safe manner. PDGF-BB and FGF-2 genes were amplified from human tissues by RT-PCR. To increase the secretion of FGF-2, a recombinant 4sFGF-2 was constructed bearing eight amino-acid residues of the signal peptide of FGF-4. PCR products were inserted into the expression vector pVax1 to produce recombinant plasmids pVax1-4sFGF2 and pVax1-PDGF-BB, which were then injected into BALB/C mice in the format of polyelectrolyte nanocomplexes with specific chitosans of controlled DDA and molecular weight, including 92-10, 80-10, and 80-80 (DDA-number average molecular weight or M(n) in kDa). ELISA assays on mice sera showed that recombinant FGF-2 and PDGF-BB proteins were efficiently expressed and specific antibodies to these proteins could be identified in sera of injected mice, but with levels that were clearly dependent on the specific chitosan used. We found high DDA low molecular weight chitosans to be efficient protein expressors with minimal or no generation of neutralizing antibodies, while lowering DDA resulted in greater antibody levels and correspondingly lower levels of detected recombinant protein. Histological analyses corroborated these results by revealing greater inflammatory infiltrates in lower DDA chitosans, which produced higher antibody titers. We found, in general, a more efficient delivery of the plasmids by subcutaneous than by intramuscular injection. Specific chitosan carriers were identified to be either efficient non-toxic therapeutic protein delivery systems or vectors for DNA vaccines.
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The functional effect of pathogenic mutations in Rab escort protein 1.
Mutat. Res.
PUBLISHED: 02-25-2009
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Choroideremia (CHM) is a chorioretinal degeneration with an X-linked pattern of inheritance. Affected males experience progressive atrophy of the choroid, retinal pigment epithelium and retina leading to eventual blindness. The CHM gene encodes Rab escort protein 1 (REP-1). REP-1 is involved in trafficking of Rab proteins in the cell. To date, the majority of reported mutations in the CHM gene cause a complete loss of REP-1 function. Here we report pathogenic mutations: a novel missense mutation, L550P; a truncation c.1542T>A, STOP; and two deletions (c.525_526delAG and c.1646delC) in the CHM gene and their phenotypic effect. To analyze the effect of mutations, the 3D structure of human REP-1 and the proteins associated with REP-1 function were modeled using sequence homology with rat proteins. In silico analysis of the missense mutation L550P suggests that the proline residue at position 550 destabilizes the beta-structural elements, and the REP-1 tertiary structure. Truncation and deletion mutants are associated with a partial or total loss of the REP-1 essential activity and protein-protein interactions as predicted by the analysis of the structure and stability of these protein products. The presumptive loss of protein was confirmed by Western Blot analysis of protein from mononuclear cells and fibroblasts (FB) from CHM patients.
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[Antimicrobial susceptibility and serotype distribution of streptococcus pneumoniae isolates in children in Tunis].
Arch Pediatr
PUBLISHED: 02-11-2009
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Streptococcus pneumoniae is a major causative agent of severe infectious diseases. More than 90 pneumococcal serotypes are known, although most invasive and noninvasive diseases are associated with a much smaller number of serotypes. The aim of this study was to determine the antimicrobial susceptibility of S. pneumoniae isolates in children, the distribution of serogroups and serotypes, and the coverage by the serotypes included in the seven-valent pneumococcal conjugate vaccine toward pneumococcal disease. This study investigated 210 nonrepetitive isolates of S. pneumoniae isolated between 1998 and 2004. Antimicrobial susceptibility was tested using the disk diffusion method as determined by the CA-SFM guidelines. Penicillin susceptibility was determined using the oxacillin 5-microg disk screening test. The MICs of penicillin G, amoxicillin, and cefotaxime were determined using the E-test (ABBIODISK). Serotype was determined using rapid latex agglutination (Pneumotest Latex) and the capsular reaction test used antisera from the Staten Serum Institute. The evaluation of susceptibility to ss-lactamins showed that 52.8% of the strains were penicillin non susceptible strains (PNSs), 16.6% had decreased susceptibility to amoxicillin, and 8.5% to cefotaxime. Among noninvasive isolates, 55.2% were PNSs and 50.4% were invasive PNSs. The PNS strains were more frequently resistant to other antibiotics, with 68.4% resistance to erythromycin, 44.1% to trimethoprim-sulfamethoxazole, and 9.9% to chloramphenicol versus 32.3, 11.1, and 1%, respectively, in penicillin-susceptible strains. The predominant serogroups/serotypes of our study were 14 (22%), 23 (14.3%), 19 (11.9%), and 4 (8.5%). The study of the vaccine serotype distribution showed that the theoretical vaccinal coverage of the seven valent vaccines was 62.8% for all the isolates, 55.2% for the invasive isolates, and 67.9% for the PNSs.
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ABA, GA(3), and nitrate may control seed germination of Crithmum maritimum (Apiaceae) under saline conditions.
C. R. Biol.
PUBLISHED: 01-27-2009
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Impaired germination is common among halophyte seeds exposed to salt stress, partly resulting from the salt-induced reduction of the growth regulator contents in seeds. Thus, the understanding of hormonal regulation during the germination process is a main key: (i) to overcome the mechanisms by which NaCl-salinity inhibit germination; and (ii) to improve the germination of these species when challenged with NaCl. In the present investigation, the effects of ABA, GA(3), NO(-)(3), and NH(+)(4) on the germination of the oilseed halophyte Crithmum maritimum (Apiaceae) were assessed under NaCl-salinity (up to 200 mM NaCl). Seeds were collected from Tabarka rocky coasts (N-W of Tunisia). The exogenous application of GA(3), nitrate (either as NaNO(3) or KNO(3)), and NH(4)Cl enhanced germination under NaCl salinity. The beneficial impact of KNO(3) on germination upon seed exposure to NaCl salinity was rather due to NO(-)(3) than to K(+), since KCl failed to significantly stimulate germination. Under optimal conditions for germination (0 mM NaCl), ABA inhibited germination over time in a dose dependent manner, but KNO(3) completely restored the germination parameters. Under NaCl salinity, the application of fluridone (FLU) an inhibitor of ABA biosynthesis, stimulated substantially seed germination. Taken together, our results point out that NO(-)(3) and GA(3) mitigate the NaCl-induced reduction of seed germination, and that NO(-)(3) counteracts the inhibitory effect of ABA on germination of C. maritimum.
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In situ potential use of metallothionein as a biomarker of cadmium contamination in Ruditapes decussatus.
Ecotoxicol. Environ. Saf.
PUBLISHED: 01-23-2009
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Cadmium (Cd) and metallothionein (MT) concentrations were analysed in the gills and digestive gland of clams Ruditapes decussatus collected from two sites of the Gulf of Gabès (Tunisia) which differ by their degree of pollution. The effect of biotic (maturity stages, protein, sex and body mass) and abiotic factors (temperature, salinity, site and season) on Cd and MT concentrations showed that in the reference site "Bordj dUngha" physiological changes caused by gamete development and maturity contributed more to changes in MT concentrations than the bioavailable Cd concentrations; whereas, in the contaminated site "El Hofra", MT induction responded to raised Cd bioavailabilities rather than to physiological changes. With a view to using MTs as metal exposure biomarker in monitoring program, our results show that the analysis in the digestive gland seem to be more relevant than in gills, and that males appear as the most promising candidates compared to females in the determination of this biomarker.
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Combined use of metoclopramide and dexamethasone as a prophylactic antiemetic in elective cesarean section under spinal anesthesia.
Middle East J Anesthesiol
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Nausea and vomiting during regional anesthesia for cesarean section still remain a major problem. We compared the efficacy of dexamethasone plus metoclopramide with dexamethasone alone for preventing nausea and vomiting during and after spinal anesthesia for cesarean section in parturients.
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A biomechanical model to simulate the effect of a high vertical loading on trunk flexural stiffness.
Comput Methods Biomech Biomed Engin
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A human trunk model was developed to simulate the effect of a high vertical loading on trunk flexural stiffness. A force-length relationship is attributed to each muscle of the multi-body model. Trunk stiffness and muscle forces were evaluated experimentally and numerically for various applied loads. Experimental evaluation of trunk stiffness was carried out by measuring changes in reaction force following a sudden horizontal displacement at the T10 level prior to paraspinal reflexes induction. Results showed that the trunk stiffness increases under small applied loads, peaks when the loads were further increased and decreases when higher loads are applied. A sensitivity analysis to muscle force-length relationship is provided to determine the models limitations. This model pointed out the importance of taking into account the changes in muscle length to evaluate the effect of spinal loads beyond the safe limit that cannot be evaluated experimentally and to predict the trunk instability under vertical load.
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Effects of parabens and isothiazolinone on the microbiological quality of baby shampoo: the challenge test.
Biocontrol Sci
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An in vitro microbial challenge test has been developed to predict the likelihood of consumer contamination of baby shampoo. Four preservatives were tested in our study: the parbens Medcide D, Medcide PB, Sepicide HB. and isothiazolinone Methylisothiazolinone/Chloromethylisothiazolinone [MI/MCI]. These preservatives were tested separately and in combination. The challenge test involved inoculating the product with Micrococcus luteus, Staphylococcus aureus, Escherichia coli, Salmonella enterica, Pseudomonas aeruginosa, Aspergillus brasiliensis and Candida albicans. Inhibition growth of these microorganisms at each preservative concentration was followed over a 28 d period. The test was used to classify products as poorly preserved, marginally preserved, or well-preserved. Interestingly, it was the combination (0.1% Isothiazolinone [MI/MCI] and 0.1% Sepicide HB) which inhibited most the microbial growth of microorganims while preserving the physicochemical properties of the product. As a result, the challenge test described can be accurately used to predict the risk of consumer contamination of cosmetic products.
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The effect of sodium lactate and lactic acid combinations on the microbial, sensory, and chemical attributes of marinated chicken thigh.
Poult. Sci.
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The present study was undertaken to evaluate the chemical, microbiological, and sensory effects of different sodium lactate (SL) and lactic acid (LA) combinations on marinated chicken thigh. The latter were treated with SL and LA combined at various concentrations, namely 0.3 and 0.03; 0.5 and 0.05; 0.6 and 0.06; 0.75 and 0.075; and 0.9 and 0.09%, respectively. The findings indicated that those combinations were efficient (P < 0.05) against the proliferation of various spoilage microorganisms, including aerobic plate count, psychrotrophic populations, Pseudomonas spp., Staphylococcus aureus, Enterobacteriaceae, and Salmonella spp. The results from chemical analyses revealed that the treated thigh underwent significant decreases (P < 0.05) in terms of pH values and total volatile base nitrogen contents. Significant differences (P < 0.05) were, however, detected with regard to their sensory attributes, with SL-LA concentrations of 0.9 and 0.09 yielding the highest scores for the color, texture, and flavor attributes. Overall, the findings demonstrated that the addition of 0.9% SL and 0.09% LA to marinated chicken can help delay the proliferation of spoilage microorganisms, prevent the generation of undesirable chemicals, improve the levels of sensory attributes, and extend the shelf life of products during refrigerated storage.
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Metabolomics analysis of Cistus monspeliensis leaf extract on energy metabolism activation in human intestinal cells.
J. Biomed. Biotechnol.
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Energy metabolism is a very important process to improve and maintain health from the point of view of physiology. It is well known that the intracellular ATP production is contributed to energy metabolism in cells. Cistus monspeliensis is widely used as tea, spices, and medical herb; however, it has not been focusing on the activation of energy metabolism. In this study, C. monspeliensis was investigated as the food resources by activation of energy metabolism in human intestinal epithelial cells. C. monspeliensis extract showed high antioxidant ability. In addition, the promotion of metabolites of glycolysis and TCA cycle was induced by C. monspeliensis treatment. These results suggest that C. monspeliensis extract has an ability to enhance the energy metabolism in human intestinal cells.
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