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Find video protocols related to scientific articles indexed in Pubmed.
Cardiac safety of (neo)adjuvant trastuzumab in the community setting: a single-center experience.
Breast Care (Basel)
PUBLISHED: 11-19-2014
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Trastuzumab improves the survival of patients with human epidermal growth factor receptor 2 (HER2)-positive breast cancer (BC). The incidence and long-term impact of trastuzumab-related cardiotoxicity in the community setting is of great clinical importance.
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Pre-treatment neutrophil-to-lymphocyte ratio affects survival in patients with advanced hepatocellular carcinoma treated with sorafenib.
Med. Oncol.
PUBLISHED: 09-03-2014
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Sorafenib is the first systemic therapy to demonstrate survival benefit in advanced hepatocellular carcinoma (HCC) in randomized controlled trials with rigorous patient selection. Neutrophil-to-lymphocyte ratio (NLR) has been shown to be associated with poor survival in various solid tumors. Our aim is to evaluate the prognostic role of NLR in HCC patients treated with sorafenib. A total of 105 advanced HCC patients treated with sorafenib were retrospectively reviewed, and relevant data from the clinical records were collected. Univariate and multivariate analysis were carried out to identify factors associated with survival. The median age of the cohort was 59.7 years, and 84.8 % were Child-Pugh class A, and 86.7 % had ECOG performance status 0 or 1. Median duration of sorafenib treatment was 100 days. Median overall survival (OS) of the entire cohort was 8.03 months. Median OS was 5.23 months (95 % CI 2.96-7.50 months) and 10.05 months (95 % IC 2.52-18.47 months) for patients with NLR > 3.5 and NLR ? 3.5, respectively (p = 0.002). Alpha-fetoprotein >1,030 ng/mL and serum albumin ?3.8 g/dL were also associated with worse prognosis (p = 0.006 and p = 0.042, respectively). The subgroup of patients with high alpha-fetoprotein, low albumin and NLR > 3.5 had median OS of 1.7 months, whereas the subgroup with none of these parameters had median OS of 16.5 months (p < 0.001). NLR affects survival in advanced HCC patients treated with sorafenib. Selecting HCC patients based on the laboratorial features may improve the therapeutic effectiveness of sorafenib.
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Short-term protection conferred by Leishvacin® against experimental Leishmania amazonensis infection in C57BL/6 mice.
Parasitol. Int.
PUBLISHED: 08-04-2014
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To date, there is no vaccine available against human leishmaniasis. Although some vaccination protocols can induce immunity in murine models, they fail to induce protection in humans. The reasons for that remain unclear. The aim of the present study was to characterize the changes in the pattern of the immune response during subcutaneous vaccination with Leishvacin® in mice. We also investigated whether IFN-? and nitric oxide synthase are indispensable for the protection elicited by the vaccine. C57BL/6 WT vaccinated mice showed smaller lesions and fewer numbers of parasites in footpads until 8 weeks post-infection. Up to this time, they produced higher levels of IFN-?, IL-2, IL-4, IL-17A and IL-10 and higher specific antibody response than control non-vaccinated mice. Moreover, we showed that IFN-?, most likely by induction of iNOS expression, is essential for immunity. However, after 12 weeks of infection, we observed loss of difference in lesion size and parasite burden between the groups. Loss of resistance was associated with the disappearance of differences in cytokine patterns between vaccinated and control mice, but not of antibody response, which remained different until a later time of infection. The reversal of resistance to L. amazonensis could not be explained by upregulation of regulatory cytokines. Our data point to a subversion of the host immune response by L. amazonensis even when a protective response was previously induced.
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Acute acalculous cholecystitis in a patient with metastatic renal cell carcinoma treated with sunitinib.
Clin Pract
PUBLISHED: 03-27-2014
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A 55-year old man was treated with sunitinib 50 mg/day for 4 weeks on and 2 weeks off, as a first-line therapy for metastatic renal cell carcinoma. During the fourth week of the first cycle, he was admitted to the Emergency Department with abdominal pain and vomiting. Acute acalculous cholecystitis was diagnosed. Sunitnib-associated cholecystitis is a rare adverse event previously reported in few cases. The mechanism behind this complication is not fully understood, although vascular endothelial dysfunction may play a role. The use of this drug is expanding in clinical oncology, and physicians should be aware of this life-threating adverse event.
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In vivo studies: comparing the administration via and the impact on the biodistribution of radiopharmaceuticals.
Nucl. Med. Biol.
PUBLISHED: 03-18-2014
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The use of in vivo assay to determine the biodistribution and subsequent inter-comparison with human parameters has been used since the dawn of science. The use of this type of test admits the metabolic equity among animals for inter-comparison. Thus, the use of Wistar rats in particular is quite frequent. Regarding routes of administration, there are three ways to test priority: jugular vein, intraocular (eye plexus) and caudal; there is a consensus that these three pathways behave in the same way, or at least very similar. Biodistribution studies of drugs, especially radiopharmaceuticals, have been using randomly any of these pathways believed to be effective in their likeness without worrying about your real analytic equity. In this study, we performed in vivo assay in 8 Wistar rats using 99mTc -labeled Herceptin to review the route of administration on the biodistribution result. Thus, four mice were injected via the intraocular (eye plexus), and four were injected via tail (caudal plexus). The results were quite disparate and call the attention of the scientific community to reassess the protocols for animal experiments, in order to have uniformity and fairness between the data and may represent a test for human inter-comparison of more reliable and trustworthy way.
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Laboratory diagnosis of amebiasis in a sample of students from southeastern Brazil and a comparison of microscopy with enzyme-linked immunosorbent assay for screening of infections with Entamoeba sp.
Rev. Soc. Bras. Med. Trop.
PUBLISHED: 01-29-2014
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Epidemiological studies on amebiasis have been reassessed since Entamoeba histolytica and E. dispar were first recognized as distinct species. Because the morphological similarity of these species renders microscopic diagnosis unreliable, additional tools are required to discriminate between Entamoeba species. The objectives of our study were to compare microscopy with ELISA kit (IVD®) results, to diagnose E. histolytica infection, and to determine the prevalence of amebiasis in a sample of students from southeastern Brazil.
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Influence of EDTA and dentine in tissue dissolution ability of sodium hypochlorite.
Aust Endod J
PUBLISHED: 11-01-2013
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This study verified whether ethylenediaminetetraacetic acid (EDTA) influences the pulp tissue dissolution capability of different concentrations of NaOCl, in the presence of dentine. NaOCl and EDTA solutions were simultaneously mixed in flasks either containing a dentine disc or those not containing a dentine disc. Previously weighed bovine pulp tissues were immersed in the solutions for 5, 15 and 30?min. The weight loss was measured. The dissolution tests were performed in triplicate. Univariate analysis of variance, along with further Tukeys honestly significant difference pairwise comparisons, was used to verify the effect of EDTA, different concentrations of NaOCl, dentine and time of incubation on the tissue dissolution. Higher concentrations of NaOCl increased the tissue dissolution. EDTA reduced the capacity of NaOCl to dissolve pulp tissue, even in presence of dentine. Dentine negatively affects the capacity of NaOCl to dissolve pulp tissue. In conclusion, the presence of EDTA and dentine negatively affects the tissue dissolution ability of NaOCl.
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Biofeedback baropodometry training evaluation: A study with children with equinus foot deformity.
Conf Proc IEEE Eng Med Biol Soc
PUBLISHED: 10-11-2013
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The lack of perception in the hindfoot increases the plantar flexion, causing irregular posture due to the foot position, a disability known as equinus foot deformity. A portable device, named baropodometer, that measures the pressure at the forefoot and hindfoot regions was built to help this population in terms of balance and posture correction. Ten hemiparetic teenager volunteers with equinus foot participated in the experiments. The results demonstrated that the proposed device increased the weight-bearing in upright stance in the paretic side, decreasing the weight in the non-paretic side. After 10 experimental sessions, performed along 6 months, the distribution of the pressure in the lower limbs was very similar. The baropodometer facilitates the rehabilitation, by biofeedbacking the pressure of the calcaneus, using the volunteers audiovisual system. The rehabilitation using the proposed device was able to recover the balance by posture correction, facilitating future gait training of these volunteers.
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The BCG Moreau RD16 deletion inactivates a repressor reshaping transcription of an adjacent gene.
Tuberculosis (Edinb)
PUBLISHED: 08-29-2013
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The Brazilian anti-tuberculosis vaccine strain Mycobacterium bovis bacillus Calmette-Guérin (BCG) BCG Moreau is unique in having a deletion of 7608 bp (RD16) that results in the truncation of a putative TetR transcriptional regulator, the ortholog of Mycobacterium tuberculosis rv3405c, BCG_M3439c. We investigated the effect of this truncation on the expression of the rv3406 ortholog (BCG_M3440), lying 81 bp downstream in the opposite orientation. RT-PCR and western blot experiments show that rv3406 mRNA and Rv3406 accumulate in BCG Moreau but not in BCG Pasteur (strain that bears an intact rv3405c), suggesting this to be a result of rv3405c truncation. Recombinant Rv3405c forms a complex with the rv3405c-rv3406 intergenic region, which contains a characteristic transcription factor binding site, showing it to have DNA binding activity. Complementation of M. bovis BCG Moreau with an intact copy of rv3405c abolishes Rv3406 accumulation. These results show that Rv3405c is a DNA binding protein that acts as a transcriptional repressor of rv3406.
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Physiological roles and potential therapeutic applications of the P2X7 receptor in inflammation and pain.
Molecules
PUBLISHED: 06-17-2013
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The P2X7 receptor (P2X7R) is a nonselective cation channel that is activated by extracellular ATP and triggers the secretion of several proinflammatory substances, such as IL-1?, IL-18, TNF-?, and nitric oxide. Recently, several preclinical studies have demonstrated that this receptor participates in inflammation and pain mechanisms. Taken together, these results indicate that P2X7R is a promising pharmacological target, and compounds that modulate the function of this receptor show potential as new anti-inflammatory medicines. In this review, we discuss aspects of P2X7R pharmacology and the participation of this protein in inflammation and pain and provide an overview of some promising compounds that have been tested as antagonists of P2X7R, with clinical applicability.
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Modulation of P2 receptors on pancreatic ?-cells by agonists and antagonists: a molecular target for type 2 diabetes treatment.
Curr Diabetes Rev
PUBLISHED: 03-20-2013
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Morbidity and mortality from diabetes mellitus (DM) are serious worldwide concerns. By the year 2030, the estimated number of diabetic patients will reach a staggering 439 million worldwide. Diabetes mellitus type 2 (DM2), which involves disturbances in both insulin secretion and resistance, is the most common form of diabetes and affects approximately 5 to 7% of the worlds population. When a patient with DM2 cannot regulate his or her blood glucose levels through diet, weight loss, or exercise, oral medications, such as hypoglycemic agents (i.e., sulphonylureas, biguanides, alpha glucosidase inhibitors and thiazolidinediones), are crucial. Here, we discuss some physiological aspects of P2 receptors on pancreatic ?-cells, which express a variety of P2 receptor isoforms. These receptors enhance glucose-dependent insulin release. In addition, we speculate on the potential of purinergic compounds as novel or additional treatments for Type 2 Diabetes mellitus.
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P-glycoprotein efflux pump plays an important role in Trypanosoma cruzi drug resistance.
Parasitol. Res.
PUBLISHED: 03-12-2013
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Drug resistance in protozoan parasites has been associated with the P-glycoprotein (Pgp), an energy-dependent efflux pump that transports substances across the membrane. Interestingly, the genes TcPGP1 and TcPGP2 have been described in Trypanosoma cruzi, although the function of these genes has not been fully elucidated. The main goal of this work was to investigate Pgp efflux pump activity and expression in T. cruzi lines submitted to in vitro induced resistance to the compounds 4-N-(2-methoxy styryl)-thiosemicarbazone (2-Meotio) and benznidazole (Bz) and to verify the stability of the resistant phenotypes during the parasite life cycle. We observed that the EC50 values for the treatment of epimastigotes with 2-Meotio or Bz were increased at least 4.7-fold in resistant lines, and this phenotype was maintained in metacyclic trypomastigotes, cell-derived trypomastigotes, and intracellular amastigotes. However, in epimastigotes, 2-Meotio resistance is reversible, but Bz resistance is irreversible. When compared with the parental line, the resistant lines exhibited higher Pgp efflux activity, reversion of the resistant phenotypes in the presence of Pgp inhibitors, cross-resistance with Pgp modulators, higher basal Pgp ATPase activity, and overexpression of the genes TcPGP1 and TcPGP2. In conclusion, the resistance induced in T. cruzi by the compounds 2-Meotio and Bz is maintained during the entire parasite life cycle. Furthermore, our data suggest the participation of the Pgp efflux pump in T. cruzi drug resistance.
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Diagnostic accuracy of pre-exercise screening questionnaire: emphasis on educational level and cognitive status.
Arch Gerontol Geriatr
PUBLISHED: 03-01-2013
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The physical activity readiness questionnaire (PAR-Q) has been the most popular simple method of screening for people who intend to engage in exercise programs. Despite of the recommendations indicating that the instrument should be applied in the age range from 15 to 69 years, the questionnaire has been widely used in elderly people. The aim of this study was to assess the diagnostic accuracy of PAR-Q in elderly women with respect to absolute and relative contraindications to exercise and verify the influence of educational level and cognitive status. Eighty-nine subjects (61-89 years) participated in the study and went through clinical exams and exercise testing. The influence of educational status, age and cognitive state (Mini-Mental State Examination, MMSE) on the PAR-Q responses was analyzed by logistic regression. The occurrences of absolute and relative contraindications were respectively 9% and 22%. The Sensitivity and Specificity were 75.0% and 19.8% (absolute) and 77.8% and 19.7% (relative). The PAR-Q results were not influenced by low educational status; age, or cognitive state. In conclusion, although the usefulness and easy applicability of the PAR-Qs questions, the responses to the questionnaire led to a high number of false positive and false negative cases, suggesting that it would not be adequate as a pre-participation screening tool in elder samples.
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Surgical treatment of severe laryngomalacia: a retrospective study of 11 case.
Braz J Otorhinolaryngol
PUBLISHED: 02-20-2013
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Laryngomalacia is the most frequent congenital abnormality of the larynx, accounting for approximately 60-75% of congenital stridor cases. Despite its benign and self-limited aspects, 10% of cases require intervention. Currently, supraglottoplasty is considered the standard treatment of severe laryngomalacia.
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Lower head temperature does not affect childrens self-paced running velocity.
Pediatr Exerc Sci
PUBLISHED: 02-15-2013
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To test if the use of a peaked cap protects children against sun radiation, allowing increased exercise performance, nineteen healthy children (10.3 ± 0.8 years old, 146.2 ± 6.9 cm, 36.8 ± 5.5 kg, 1.2 ± 0.1 m2 and 44.1 ± 2.8 mL.kg-1.min-1) took part in 4 experimental situations: 2 initial familiarization runs and 2 self-paced 6km runs (4 × 1.5 km exercise bouts with 3min rest intervals) one of them wearing a peaked cap (CAP) and another situation without the cap (NOCAP). The CAP and NOCAP situations were randomized. Exercise was performed outdoors 3-7 days apart. Environmental variables were measured every 10min, and physiological variables were measured before and after each run and during the rest intervals. Running velocity did not differ between CAP and NOCAP situations. The mean head temperature was reduced by 1.1 °C in the CAP situation (p < .05). Average skin temperature, mean heart rate, rate of perceived exertion and wet bulb and globe temperature did not differ between CAP and NOCAP. The decrease in the mean head temperature was not sufficient to alter running velocity.
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Control of size in losartan/copper(II) coordination complex hydrophobic precipitate.
Mater Sci Eng C Mater Biol Appl
PUBLISHED: 02-11-2013
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Reaction of highly soluble orally active, non-peptide antihypertensive drug losartan with copper(II) leads to the spontaneous formation of a very insoluble 2:1 covalent complex, which self assembles in a hydrophobic supramolecular structure of nanometric dimensions. Thermal analysis showed that Los/Cu(II) complex presents intermediate stability in comparison with its precursors KLos and Cu(OAc)2·H2O. Isothermal titration calorimetry indicated complexation to be a stepwise process, driven by enthalpy and entropy. Zeta potential and DLS measurements showed that it is possible to control the size and charge of nanoprecipitates by adjusting the relative concentration of Los(-) and Cu(II).
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Laryngeal pathologies as an etiologic factor of obstructive sleep apnea syndrome in children.
Int. J. Pediatr. Otorhinolaryngol.
PUBLISHED: 01-17-2013
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Obstructive sleep apnea syndrome is a chronic condition of airway obstruction, common in children, with known clinical consequences. The etiology of OSAS in children stems from a combination of obstructing structural factors and neuromotor factors. In children, tonsilar hypertrophy accounts for this condition in most cases, however, in about 20% of the cases, other causes are involved. For the treatment of apnea in children, adenotonsillectomy is the most commonly performed procedure, though we should indicate the treatment according to its underlying cause. The aim of this paper is to highlight other possible apnea etiologies, contributing to appropriate diagnosis and treatment. We present two cases of patients with apnea of unusual origin: one of respiratory dystonia and another of supraglottic stenosis as the causative factor of obstructive sleep apnea. In conclusion, we emphasize the need for the ENT to perform detailed research on the etiology of apnea, for individualized treatment.
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Genome sequence of Mycobacterium bovis BCG Moreau, the Brazilian vaccine strain against tuberculosis.
J. Bacteriol.
PUBLISHED: 09-15-2011
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Mycobacterium bovis bacillus Calmette-Guérin (BCG) is the only vaccine available against tuberculosis, and the strains used worldwide represent a family of daughter strains with distinct genotypic characteristics. Here we report the complete genome sequence of M. bovis BCG Moreau, the strain in continuous use in Brazil for vaccine production since the 1920s.
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Proteomic profile of culture filtrate from the Brazilian vaccine strain Mycobacterium bovis BCG Moreau compared to M. bovis BCG Pasteur.
BMC Microbiol.
PUBLISHED: 04-20-2011
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Bacille Calmette-Guerin (BCG) is currently the only available vaccine against tuberculosis (TB) and comprises a heterogeneous family of sub-strains with genotypic and phenotypic differences. The World Health Organization (WHO) affirms that the characterization of BCG sub-strains, both on genomic and proteomic levels, is crucial for a better comprehension of the vaccine. In addition, these studies can contribute in the development of a more efficient vaccine against TB. Here, we combine two-dimensional electrophoresis (2DE) and mass spectrometry to analyse the proteomic profile of culture filtrate proteins (CFPs) from M. bovis BCG Moreau, the Brazilian vaccine strain, comparing it to that of BCG Pasteur. CFPs are considered of great importance given their dominant immunogenicity and role in pathogenesis, being available for interaction with host cells since early infection.
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Myosins and DYNLL1/LC8 in the honey bee (Apis mellifera L.) brain.
J. Insect Physiol.
PUBLISHED: 03-23-2011
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Honey bees have brain structures with specialized and developed systems of communication that account for memory, learning capacity and behavioral organization with a set of genes homologous to vertebrate genes. Many microtubule- and actin-based molecular motors are involved in axonal/dendritic transport. Myosin-Va is present in the honey bee Apis mellifera nervous system of the larvae and adult castes and subcastes. DYNLL1/LC8 and myosin-IIb, -VI and -IXb have also been detected in the adult brain. SNARE proteins, such as CaMKII, clathrin, syntaxin, SNAP25, munc18, synaptophysin and synaptotagmin, are also expressed in the honey bee brain. Honey bee myosin-Va displayed ATP-dependent solubility and was associated with DYNLL1/LC8 and SNARE proteins in the membrane vesicle-enriched fraction. Myosin-Va expression was also decreased after the intracerebral injection of melittin and NMDA. The immunolocalization of myosin-Va and -IV, DYNLL1/LC8, and synaptophysin in mushroom bodies, and optical and antennal lobes was compared with the brain morphology based on Neo-Timm histochemistry and revealed a distinct and punctate distribution. This result suggested that the pattern of localization is associated with neuron function. Therefore, our data indicated that the roles of myosins, DYNLL1/LC8, and SNARE proteins in the nervous and visual systems of honey bees should be further studied under different developmental, caste and behavioral conditions.
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Factors associated with heavy alcohol use among students in Brazilian capitals.
Rev Saude Publica
PUBLISHED: 03-27-2010
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To evaluate the association between heavy use of alcohol among students and family, personal and social factors.
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The influence of temperature on the behavior of burrowing in larvae of the blowflies, Chrysomya albiceps and Lucilia cuprina, under controlled conditions.
J. Insect Sci.
PUBLISHED: 07-21-2009
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Blowflies use discrete, ephemeral substrates for larval development. After exhaustion of the food supply, larvae will disperse in search of sites to burrow and pupate or will seek other sources of food in a process known as post-feeding larval dispersal. In this study, the effect of temperature was investigated as it is one of the most important aspects of the environmental variables in this process. 800 larvae of the blowflies Chrysomya albiceps (Wiedemann 1819) and Lucilia cuprina (Wiedemann 1830) (Diptera: Calliphoridae) were incubated in tubes covered with vermiculite at 15, 20, 25 and 30 degrees C. For each pupa, the body weight, sex and depth of burrowing were determined. Statistical tests were used to examine the relationship of depth of burrowing and body weight to the temperature at which burrowing occurred. Depth of burrowing was affected differently by temperature for both of the species studied; L. cuprina larvae burrowed deeper at lower and higher temperatures while C. albiceps larvae burrowed less at extreme temperatures. Additionally, temperature had a significant effect on the body weight of L. cuprina larvae as body weight decreased as temperature increased, whereas for C. albiceps, pupal weight increased up to 25 degrees C and then decreased abruptly at a higher temperatures. The maximum body weight was also differently affected in the two species; in L. cuprina, the maximal weight was at 15 degrees C and for C. albiceps weight was maximal at 20 degrees C.
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Identification of major royal jelly proteins in the brain of the honeybee Apis mellifera.
J. Insect Physiol.
PUBLISHED: 05-05-2009
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The consumption of royal jelly (RJ) determines the differences between castes and behavioral development in the honeybee Apis mellifera. However, it is not known whether the proteins of RJ are related to these differences, or which proteins are responsible for the changes. To understand the functions of RJ proteins that are present in other tissues of the bee, in addition to hypopharyngeal gland, we used a polyclonal antibody anti-MRJP1 to investigate the presence of this protein in nervous system of honeybee. This study showed the presence of three polypeptides (p57, p70 and p128) in specific tissues of bee brain. Mushroom body, optic lobe and antennal lobe neuropils all contained proteins recognized by anti-MRJP1. Proteomic analysis showed that the three polypeptides are correlated with proteins of the MRJP family. p57 is correlated with MRJP1, p70 with MRJP3, while p128 may be an oligomeric form or a new polypeptide. Immunostaining of the brain and hypopharyngeal gland revealed differential expression of MRJPs in various brain regions and in different honeybee castes and subcastes. The identification and localization of these MRJPs contribute to the elucidation of the biological roles of this protein family.
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The Valsalva maneuver in Chagas disease patients without cardiopathy.
Clin. Auton. Res.
PUBLISHED: 04-14-2009
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To perform a meta-analysis of studies using the Valsalva ratio (VR) in Chagas disease (ChD) patients without cardiopathy in comparison to control subjects in order to determine if vagal heart modulation is impaired in early forms of ChD.
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Reduced expression of IL-3 mediates intestinal mast cell depletion in diabetic rats: role of insulin and glucocorticoid hormones.
Int J Exp Pathol
PUBLISHED: 04-02-2009
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Rats turned diabetic by alloxan treatment are refractory to systemic anaphylactic shock, in a direct association with reduced intestinal haemorrhage and tissue response to antigen challenge. As diabetic rats show reduction in mast cell numbers in different body compartments, this study was undertaken to investigate the influence of alloxan diabetes on mast cell population as well as the expression of the mast cell growth factor interleukin (IL)-3 in the small intestine of rats. We also analysed the putative involvement of endogenous insulin and glucocorticoid hormones in this phenomenon. There was a significant decrease in the number of mast cells present in the small intestine (ileum segment) of diabetic rats. Likewise, the immunohistochemical analysis revealed that IL-3 labelling was markedly attenuated in diabetic rats, as compared with normal animals, a phenomenon which paralleled with a decreased mRNA expression as attested by Reverse transcriptase-polymerase chain reaction technique. Treatment with insulin and with the steroid receptor antagonist RU 486 restored basal mast cell numbers, normal levels of IL-3 labelling and mRNA expression for IL-3 in the ileum of diabetic rats. In conclusion, our findings show that there is a causative relationship between down-regulation of mast cell numbers and the expression of IL-3 associated with diabetic state. In addition, as both parameters were suppressed by administration of insulin and RU 486, it indicates that an imbalance between the systemic levels of insulin and glucocorticoid hormones seems to be implicated in the reduction in intestinal mast cell population and refractoriness to antigen provocation in alloxan diabetes.
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Application of pyridylazo and thiazolylazo reagents in flow injection preconcentration systems for determination of metals.
Talanta
PUBLISHED: 02-09-2009
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Pyridylazo and thiazolylazo reagents are synthetic dyes widely used in analytical chemistry. These reagents are also very attractive for use in preconcentration systems. This paper covers the application of pyridylazo and thiazolylazo reagents in flow injection systems for the determination of metals. The article discusses flow injection preconcentration systems with solid-phase extraction, precipitation and cloud point extraction. The use of pyridylazo and thiazolylazo reagents in flow injection detection systems is also presented. The relative advantages and drawbacks of these systems are discussed. The application of pyridylazo and thiazolylazo reagents in new systems is presented in the concluding part of this review article.
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Insulin-binding canavalin is present in Canavalia ensiformis seed coat.
Protein Pept. Lett.
PUBLISHED: 02-02-2009
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An insulin-binding protein was isolated from Canavalia ensiformis seed coat, by using an insulin-Sepharose 4B affinity chromatography, and the protein was identified as canavalin (Canavalia 7S globulin) by mass spectrometry analysis. The major novelty of these data is the acidic nature of this globulin insulin-binding, in contrast to the basic Bg-like insulin-binding proteins so far reported in plants.
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Quality of life in children with sleep-disordered breathing.
Braz J Otorhinolaryngol
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Children may present sleep-disordered breathing (SDB) and suffer with adverse effects upon their quality of life.
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Bioluminescent imaging of Trypanosoma cruzi infection in Rhodnius prolixus.
Parasit Vectors
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Usually the analysis of the various developmental stages of Trypanosoma cruzi in the experimentally infected vertebrate and invertebrate hosts is based on the morphological observations of tissue fragments from animals and insects. The development of techniques that allow the imaging of animals infected with parasites expressing luciferase open up possibilities to follow the fate of bioluminescent parasites in infected vectors.
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Determination of copper, iron, nickel and zinc in ethanol fuel by energy dispersive X-ray fluorescence after pre-concentration on chromatography paper.
Anal. Chim. Acta
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This paper presents an alternative analytical method employing energy dispersive X-ray fluorescence (EDXRF) to determine copper, iron, nickel and zinc ions in ethanol fuel samples after a pre-concentration procedure. Our pre-concentration strategy utilizes analyte retention on cation exchange chromatography paper, a convenient substrate for direct EDXRF measurements. The repeatability, expressed in terms of RSD of standard solutions containing 0.25 ?g mL(-1) of Cu, Fe, Ni and Zn, and calculated from fifteen consecutive measurements, was 2.5, 2.8, 3.0, and 2.7%, respectively. The limits of detection (LOD), defined as the analyte concentration that gives a response equivalent to three times the standard deviation of the blank (n=10), were found to be 13, 15, 15 and 12 ?g L(-1) for Cu, Fe, Ni and Zn, respectively. The proposed method was applied to Cu, Fe, Ni and Zn determination in hydrated ethanol fuel samples collected from different gas stations.
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What is Visualize?

JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

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We use abstracts found on PubMed and match them to JoVE videos to create a list of 10 to 30 related methods videos.

Video X seems to be unrelated to Abstract Y...

In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.