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In JoVE (1)
Other Publications (67)
- The Journal of Urology
- Applied Ergonomics
- Journal of the Optical Society of America. A, Optics, Image Science, and Vision
- The International Journal of Oral & Maxillofacial Implants
- Journal of Colloid and Interface Science
- Bioorganic & Medicinal Chemistry Letters
- Clinical Orthopaedics and Related Research
- Journal of Vascular and Interventional Radiology : JVIR
- Journal of Bone and Mineral Research : the Official Journal of the American Society for Bone and Mineral Research
- Clinical Orthopaedics and Related Research
- Clinical Orthopaedics and Related Research
- Osteoporosis International : a Journal Established As Result of Cooperation Between the European Foundation for Osteoporosis and the National Osteoporosis Foundation of the USA
- Applied Optics
- Insect Biochemistry and Molecular Biology
- AJNR. American Journal of Neuroradiology
- The Journal of Biological Chemistry
- Bioresource Technology
- Development Genes and Evolution
- The New Zealand Medical Journal
- Archives of Pathology & Laboratory Medicine
- Physical Review Letters
- The Journal of Pharmacy and Pharmacology
- Journal of Chromatography. A
- Canadian Journal of Anaesthesia = Journal Canadien D'anesthésie
- Journal of Applied Genetics
- Archives of Insect Biochemistry and Physiology
- Journal of Lipid Research
- American Journal of Medical Genetics. Part A
- Journal of Applied Genetics
- Calcified Tissue International
- Journal of Colloid and Interface Science
- Community Eye Health / International Centre for Eye Health
- American Journal of Physiology. Endocrinology and Metabolism
- Pharmaceutical Research
- Respiratory Medicine
- The Journal of Cell Biology
- Mayo Clinic Proceedings. Mayo Clinic
- Optics Letters
- Current Pharmaceutical Biotechnology
- McGill Journal of Medicine : MJM : an International Forum for the Advancement of Medical Sciences by Students
- Journal of Physics. Condensed Matter : an Institute of Physics Journal
- Cancer Research
- Current Drug Delivery
- Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
- The American Journal of the Medical Sciences
- Insect Biochemistry and Molecular Biology
- Journal of Endourology / Endourological Society
- Journal of the Optical Society of America. A, Optics, Image Science, and Vision
- Journal of Clinical Densitometry : the Official Journal of the International Society for Clinical Densitometry
- Chemical Communications (Cambridge, England)
- Journal of Advanced Pharmaceutical Technology & Research
- European Journal of Medicinal Chemistry
- Respirology (Carlton, Vic.)
- Applied Optics
- Respiratory Medicine
- Cancer Research
- International Journal of Pharmaceutics
- The Journal of Antimicrobial Chemotherapy
- International Journal of Pharmaceutics
- Journal of Clinical Monitoring and Computing
- Amino Acids
Articles by Rajesh Patel in JoVE
Preparation of embryos for Electron Microscopy of the Drosophila embryonic heart tube
Nadine H. Soplop1,2, Rajesh Patel1, Sunita G. Kramer1,2
1Joint Graduate Program in Cell and Developmental Biology, UMDNJ-Graduate School of Biomedical Sciences and Rutgers: The State University of New Jersey, 2Department of Pathology and Laboratory Medicine, Robert Wood Johnson Medical School, University of Medicine and Dentistry of New Jersey
We describe a process for fixation, embedding, sectioning, and imaging of late stage Drosophila embryos for Trasmission Electron Microscopy of the embryonic heart tube. This technique allows for the visualization of the heart tube lumen as well as the basement membrane, which lines the lumen of the heart.
Other articles by Rajesh Patel on PubMed
Bilateral Laparoscopic Inguinal Hernia Repair Can Complicate Subsequent Radical Retropubic Prostatectomy
The Journal of Urology. Feb, 2002 | Pubmed ID: 11792935
Artificial Urinary Sphincter Placement in Men After Cystectomy with Orthotopic Ileal Neobladder: Continence, Complications, and Quality of Life
Urology. Apr, 2002 | Pubmed ID: 11927310
To review our experience regarding the overall efficacy and safety of an artificial urinary sphincter (AUS) in men with stress urinary incontinence (SUI) after cystoprostatectomy with an orthotopic ileal neobladder.
Applied Ergonomics. Sep, 2002 | Pubmed ID: 12236660
Threshers are used extensively on Indian farms for threshing grains, but are involved in a significant proportion of limb crush injuries. International safety standards are somewhat difficult to enforce because manufacture of machines is done at widely dispersed local workshops. Locally made machines are used for crop production and post-harvesting operations, with a great deal of manual work. This technical note reports the results of a study to develop a cost effective, improved design for safe operation of threshers based on ergonomic principles.
Journal of the Optical Society of America. A, Optics, Image Science, and Vision. Dec, 2002 | Pubmed ID: 12469745
We describe a postgrowth method to produce passband filters with different center wavelengths from a single growth run by irreversibly changing the refractive index of a layer or a series of layers within the filter. This leads to a new type of filter, the passband-shifting filter, whose center wavelength can be irreversibly shifted from lambda0 to lambda0 - deltalambda after the filter has been grown. The passband shift can be controlled exactly by proper design of the multilayer. We present the theory behind passband-shifting-filter design along with transfer-matrix simulations and preliminary experimental results for a two-cavity filter, using lateral oxidation of AlxGa1-x As-based materials to effect the passband shift.
The International Journal of Oral & Maxillofacial Implants. May-Jun, 2003 | Pubmed ID: 12814312
The aim of this study was to report the outcome of sinus augmentation surgery with autogenous bone grafting in routine dental implant practice.
Journal of Colloid and Interface Science. Jul, 2003 | Pubmed ID: 12909059
Effective viscosity of a magnetic fluid as a function of applied magnetic field oriented in the perpendicular direction of the capillary flow is determined. Close agreement with the Shliomis expression derived on the basis of effective field method is observed.
Bioorganic & Medicinal Chemistry Letters. Sep, 2003 | Pubmed ID: 12941345
A series of oxindoles demonstrating inhibition of the phosphorylation of biotinylated substrates of Syk and IgE/Fc epsilon RI triggered basophil cell degranulation has been identified. A study of the SAR around sulfonamide 31 (IC(50)=5 nM, EC(50)=1400 nM) is discussed. The modest cellular activity representative of the sulfonamide series was overcome when the Polar Surface Area was lowered to <110 A(2), leading to the identification of amide 32 (IC(50)=145 nM, EC(50)=100 nM).
Clinical Orthopaedics and Related Research. Sep, 2003 | Pubmed ID: 12966293
When doing a proximal tibial prosthetic reconstruction, some surgeons think that the subcutaneous location of the proximal tibia necessitates a gastrocnemius muscle flap for closure and function. In this study, 22 patients with bone tumors had proximal tibial segmental prosthetic replacement using direct reattachment of the patellar tendon to the prosthesis without the use of a muscle flap. Two of 19 patients required reoperation in the postoperative period for hematomas. Both were free of infection or other complications at 24 months mean followup. No other wound complications occurred despite initiation of chemotherapy 2 to 3 weeks after surgery in patients with high-grade malignant tumors (15 of 19). The mean followup was 38.6 months (range, 13-99 months). The patients ranged in age from 15 to 74 years (mean, 39 years). The range of motion achieved postoperatively showed a mean of 97 degrees (+/-16.3 degrees). All patients had full passive extension with a mean extensor lag of 7.5 degrees. The mean Musculoskeletal Tumor Society score was 27.6 (+/- 2.0). These results of patients without muscle flaps compare favorably with published results advocating gastrocnemius flaps for the attachment of the patellar tendon to the prosthesis.
SIR Reporting Standards for the Treatment of Acute Limb Ischemia with Use of Transluminal Removal of Arterial Thrombus
Journal of Vascular and Interventional Radiology : JVIR. Sep, 2003 | Pubmed ID: 14514861
Journal of Bone and Mineral Research : the Official Journal of the American Society for Bone and Mineral Research. Nov, 2003 | Pubmed ID: 14606507
Combining information from different types of BMD measurement should improve the evaluation of patients' risk of fracture. This study used a bivariate gaussian model to examine the effect of combining two different BMD measurements. The results show that, in practice, there is little benefit unless the measurements are completely unrelated.
Outcomes of Total Hip Arthroplasty Are Similar for Patients with Displaced Femoral Neck Fractures and Osteoarthritis
Clinical Orthopaedics and Related Research. Apr, 2004 | Pubmed ID: 15123940
This study attempted to evaluate whether total hip arthroplasty for displaced femoral neck fractures had significantly different outcomes when compared with total hip arthroplasty for osteoarthritis. This is a retrospective study of 60 patients who had total hip arthroplasties between 1997 and 2001. Thirty patients (mean age, 79.7 years) had total hip arthroplasties for displaced femoral neck fractures; 30 patients (mean age, 76.9 years) were treated with total hip arthroplasties for osteoarthritis. The same surgeon used the modified lateral approach for all surgeries. All patients had radiographic assessment, physical examination, and evaluation with the Harris hip score. The mean followup was 38 months. The mean Harris hip score for the 25 patients treated with a total hip arthroplasty for a femoral neck fracture was 81 points; the mean hip score for the 27 patients treated with a total hip arthroplasty for osteoarthritis was 87 points. No statistically significant differences between these groups were observed. Patients who were treated with a total hip arthroplasty for a femoral neck fracture did not have increased perioperative morbidity compared with patients who had a total hip arthroplasty for osteoarthritis. This study suggests that the outcomes for total hip arthroplasties in this consecutive series of patients treated for displaced femoral neck fractures and osteoarthritis are comparable.
Clinical Orthopaedics and Related Research. May, 2004 | Pubmed ID: 15187832
Spinal injuries occur frequently in the patient with polytrauma making the knowledge of the evaluation and treatment of these injuries invaluable to the trauma team. In the immediate moments after these injuries, critical steps can be taken to prevent additional injury and insure maximum neurologic and functional recovery of the patient. A simple, standardized approach to treating the patient at the scene, examining the patient in the trauma admitting area, ordering appropriate radiographic studies, and instituting early treatment can markedly influence a patient's maximal recovery. Furthermore, background knowledge in the classification and ultimate treatment goals allows for an effective communication between the initial treating team and the spinal surgeons involved. The work on indicators of potential spinal instability by White and Panjabi and the three-column classification of spinal injuries of Denis lends insight to the potential consequences of spinal trauma. A thorough appreciation of these concepts puts evaluation and treatment of these injuries into a logical framework with which spinal injuries initially can be approached.
An Evaluation of the United Kingdom National Osteoporosis Society Position Statement on the Use of Peripheral Dual-energy X-ray Absorptiometry
Osteoporosis International : a Journal Established As Result of Cooperation Between the European Foundation for Osteoporosis and the National Osteoporosis Foundation of the USA. Jun, 2004 | Pubmed ID: 15205722
A recent position statement issued by the UK National Osteoporosis Society recommends a triage approach to the use of peripheral dual-energy X-ray absorptiometry (pDXA) devices. Patients with a forearm T-score greater than -1 or less than -2.5 are regarded as normal or osteoporotic, respectively, while those with a T-score between -1 and -2.5 are sent for further assessment with spine and hip DXA. We have evaluated the NOS pDXA algorithm by comparing it with the alternative strategies of relying on forearm BMD alone, or performing spine and hip DXA in every patient. The evaluation was carried out using a mathematical model, and the predictions were compared with in vivo data obtained in patients referred for investigation by their general practitioner. In the model the population distribution of spine, hip, and forearm BMD was described by a trivariant Gaussian function. Relative risks of fracture were taken from a meta-analysis. The three strategies were compared using receiver operating characteristic (ROC) curves in which the percentage of future fracture cases identified was plotted against the percentage of the whole population found to have osteoporosis. ROC curves plotted for the discrimination of hip, vertebral, and Colles fracture risk and the risk of a fracture at any skeletal site were similar for all three strategies, with the curves for the NOS pDXA algorithm nearly identical to those for spine and hip DXA. For the case of hip fracture, vertebral fracture, or a fracture at any site, forearm BMD was slightly inferior to the NOS algorithm, but the reverse was true for Colles fracture. The small difference between the ROC curves suggests that forearm BMD used alone can reproduce clinical decision-making with the NOS pDXA algorithm provided that a T-score threshold of T=-2.1 is used for the diagnosis of osteoporosis, instead of the conventional figure of T=-2.5. Results from the in vivo study were in good agreement with the predictions of the model, although some differences were observed that were explained by inaccuracies in the forearm reference data. We conclude that use of forearm BMD alone with a modified T-score threshold of -2.1 would save the need for spine and hip DXA scans and identify only slightly fewer fracture cases for treatment.
Applied Optics. Jun, 2004 | Pubmed ID: 15218601
A temperature-dependent magneto-optical study of three different temperature-sensitive fluids was carried out. The changes in transmitted intensity as a function of applied magnetic field and temperature are recorded. The study provides an alternative technique for determining the Curie temperature of such fluids, and it is also feasible for the monitoring of temperature changes of such fluids optically within a limited time span.
CAMP-dependent Protein Kinase of Manduca Sexta Phosphorylates but Does Not Activate the Fat Body Triglyceride Lipase
Insect Biochemistry and Molecular Biology. Dec, 2004 | Pubmed ID: 15544940
cAMP-dependent-protein kinase (PKA) is a central player of the adipokinetic signal that controls the mobilization of stored lipids in the fat body. Previous studies showed that adipokinetic hormone (AKH) rapidly activates PKA from the fat body of Manduca sexta (Arrese et al. (J. Lipid. Res. 40(3): 556)). As a part of our investigation on lipolysis in insects, here we report the purification and characterization of the catalytic subunit of PKA from the fat body of M. sexta and its role in the direct activation of the TG lipase in vitro. PKA was purified to apparent homogeneity and the identity of the protein was confirmed by MALDI-TOF and Western blot analysis. The enzyme showed a high affinity for Mg-ATP (Km = 39 microM) and Kemptide (Km = 31 microM) and was strongly inhibited by the PKA specific inhibitors PKI 5-24 and H89. Manduca sexta PKA only recognized serine residues as phosphate acceptor; theronine or tyrosine containing peptides were not phosphorylated. Purified fat body TG-lipase proved to be a good substrate of the purified kinase. However, phosphorylation of the lipase did not enhance the lipolytic activity of the enzyme in vitro. These results suggest that, besides lipase phosphorylation, the mechanism of AKH-induced activation of the lipolysis requires the involvement of other proteins and/or signals.
AJNR. American Journal of Neuroradiology. Jan, 2005 | Pubmed ID: 15661693
We present a case of serologically proved West Nile virus (WNV) flaccid paralysis of the right upper extremity. Radiologic correlation revealed striking T2 hyperintensities in the anterior horns of the cervical spinal cord, similar to those seen in cases of poliomyelitis. Recognition of the MR imaging findings in cases of WNV flaccid paralysis can provide early evidence of infection.
Activation of the Lipid Droplet Controls the Rate of Lipolysis of Triglycerides in the Insect Fat Body
The Journal of Biological Chemistry. Jun, 2005 | Pubmed ID: 15829485
The hydrolysis of triglyceride (TG) stored in the lipid droplets of the insect fat body is under hormonal regulation by the adipokinetic hormone (AKH), which triggers a rapid activation cAMP-dependent kinase cascade (protein kinase A (PKA)). The role of phosphorylation on two components of the lipolytic process, the TG-lipase and the lipid droplet, was investigated in fat body adipocytes. The activity of purified TG-lipase determined using in vivo TG-radiolabeled lipid droplets was unaffected by the phosphorylation of the lipase. However, the activity of purified lipase was 2.4-fold higher against lipid droplets isolated from hormone-stimulated fat bodies than against lipid droplets isolated from unstimulated tissue. In vivo stimulation of lipolysis promotes a rapid phosphorylation of a lipid droplet protein with an apparent mass of 42-44 kDa. This protein was identified as "Lipid Storage Droplet Protein 1" (Lsdp1). In vivo phosphorylation of this protein reached a peak approximately 10 min after the injection of AKH. Supporting a role of Lsdp1 in lipolysis, maximum TG-lipase activity was also observed with lipid droplets isolated 10 min after hormonal stimulation. The activation of lipolysis was reconstituted in vitro using purified insect PKA and TG-lipase and lipid droplets. In vitro phosphorylation of lipid droplets catalyzed by PKA enhanced the phosphorylation of Lsdp1 and the lipolytic rate of the lipase, demonstrating a prominent role PKA and protein phosphorylation on the activation of the lipid droplets. AKH-induced changes in the properties of the substrate do not promote a tight association of the lipase with the lipid droplets. It is concluded that the lipolysis in fat body adipocytes is controlled by the activation of the lipid droplet. This activation is achieved by PKA-mediated phosphorylation of the lipid droplet. Lsdp1 is the main target of PKA, suggesting that this protein is a major player in the activation of lipolysis in insects.
Bioresource Technology. Apr, 2006 | Pubmed ID: 15939589
This work investigated the extraction of cashew nut shell liquid (CNSL) using supercritical carbon dioxide (SC-CO(2)). Effects of process parameters such as extraction pressure, temperature and flow rate of SC-CO(2) were investigated. The yield of CNSL increased with increase in pressure, temperature and mass flow rate of SC-CO(2). However, under different operating conditions, the composition of CNSL varied. The study of physical properties and chemical composition of the oil obtained through super critical fluid extraction (SCFE) showed better quality as compared to the CNSL obtained through thermal route. Experimental results were compared with diffusion based mass transfer model. Based on this simple model, extraction time was optimized.
A Comparative Study of Sperm Morphology, Cytology and Activation in Caenorhabditis Elegans, Caenorhabditis Remanei and Caenorhabditis Briggsae
Development Genes and Evolution. Apr, 2006 | Pubmed ID: 16389557
Studies of sterile mutants in Caenorhabditis elegans have uncovered new insights into fundamental aspects of gamete cell biology, development, and function at fertilization. The genome sequences of C. elegans, Caenorhabditis briggsae and Caenorhabditis remanei allow for informative comparative studies among these three species. Towards that end, we have examined wild-type sperm morphology and activation (spermiogenesis) in each. Light and electron microscopy studies reveal that general sperm morphology, organization, and ultrastructure are similar in all three species, and activation techniques developed for C. elegans were found to work well in both C. briggsae and C. remanei. Despite important differences in the reproductive mode between C. remanei and the other two species, most genes required for spermiogenesis are conserved in all three. Finally, we have also examined the subcellular distribution of sperm epitopes in C. briggsae and C. remanei that cross-react with anti-sera directed against C. elegans sperm proteins. The baseline data in this study will prove useful for the future analysis and interpretation of sperm gene function across nematode species.
The New Zealand Medical Journal. 2006 | Pubmed ID: 16582973
To identify the appropriateness of calls to on-call house officers in a major tertiary teaching hospital.
Molecular Classification of Human Cancers Using a 92-gene Real-time Quantitative Polymerase Chain Reaction Assay
Archives of Pathology & Laboratory Medicine. Apr, 2006 | Pubmed ID: 16594740
Correct diagnosis of the tissue origin of a metastatic cancer is the first step in disease management, but it is frequently difficult using standard pathologic methods. Microarray-based gene expression profiling has shown great promise as a new tool to address this challenge.
Physical Review Letters. Mar, 2006 | Pubmed ID: 16605956
Magnetically induced diffraction patterns by micron sized magnetic spheres dispersed in a ferrofluid disappear at a certain critical magnetic field. This critical field is found to depend on the concentration of the ferrofluid and on the volume of the magnetic spheres. We attribute this effect to the zero forward scattering by magnetic spheres as predicted by Kerker, Wang, and Giles [J. Opt. Soc. Am. 73, 765 (1983)]. We suggest that such a dispersion can be used to study the optical analogues of localization of electrons in condensed matter, the Hall effect, and the anisotropic diffusion, etc. The combination of the micron sized magnetic spheres and the ferrofluid will also be useful to design magnetically tunable photonic devices.
The Journal of Pharmacy and Pharmacology. Jun, 2006 | Pubmed ID: 16734983
The accelerating effect of polyethylene glycol 400 on small intestinal transit has been previously reported. The aim of this study was to investigate the influence of other solubility-enhancing excipient, propylene glycol, D-alpha-tocopheryl-polyethylene glycol-1,000 succinate (VitE-TPGS) and Capmul MCM, on human intestinal transit. A 5-g dose of each excipient was administered to seven healthy male subjects. Propylene glycol and VitE-TPGS were administered dissolved in 150 mL water. Capmul MCM was administered in the form of four 000 hard gelatin capsules to mask its taste and then given with 150 mL water. On a separate occasion, 150 mL water was administered as the control. Each formulation was radiolabelled with technetium-99 m to follow its transit using a gamma camera. The mean small intestinal transit times were 234, 207, 241 and 209 min for the control, propylene glycol, VitE-TPGS and Capmul MCM treatments, respectively. Although there were differences in the small intestinal transit times for the excipients investigated compared with the control, none of the results were statistically significant. Unlike polyethylene glycol 400 at the same dose of 5 g, the excipients tested (propylene glycol, VitE-TPGS and Capmul MCM) had little or no impact on small intestinal transit.
Journal of Chromatography. A. Aug, 2006 | Pubmed ID: 16814300
This manuscript summarises the techno-economic feasibility of refined cashew nut shell liquid (CNSL). A simple mass transfer based mathematical model for the yield prediction is presented. The process parameters and extraction time for maximum profit and purity of the product were optimized. The optimum extraction time for maximum profit and purity was found to be 0.9h at 300 bar and 323 K. The influence of the different costs, such as fixed cost, raw material cost, labor cost, utility cost, etc. on profit and cost of production of the extract is also presented.
Neurology. Jul, 2006 | Pubmed ID: 16864836
Sixty-eight patients with convulsive status epilepticus (SE) were randomly assigned to two groups to study the efficacy of sodium valproate (VPA) and phenytoin (PHT). Seizures were aborted in 66% in the VPA group and 42% in the PHT group. As a second choice in refractory patients, VPA was effective in 79% and PHT was effective in 25%. The side effects in the two groups did not differ. Sodium valproate may be preferred in convulsive SE because of its higher efficacy.
Canadian Journal of Anaesthesia = Journal Canadien D'anesthésie. Aug, 2006 | Pubmed ID: 16873341
To determine the effect of reactive hyperemia on human forearm vein area.
Journal of Applied Genetics. 2006 | Pubmed ID: 16877802
The present study investigated the occurrence of 2 autosomal recessive genetic diseases, bovine citrullinaemia and deficiency of uridine monophosphate synthase (DUMPS), in Indian Holstein cattle. The polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis was performed on a group of 642 animals, mainly HF and HF crossbred cattle, to identify carriers of these diseases. None of the animals were carriers of citrullinaemia or DUMPS. It is possible that with the mounting selection pressure, the international gene pool may diminish, and consequently the risk of dissemination of inherited defects will increase. It is therefore recommended to screen breeding bulls for their breed-specific genetic diseases before they are inducted in artificial insemination programmes, to minimize the risk.
Adipokinetic Hormone-induced Mobilization of Fat Body Triglyceride Stores in Manduca Sexta: Role of TG-lipase and Lipid Droplets
Archives of Insect Biochemistry and Physiology. Oct, 2006 | Pubmed ID: 16983668
Triglycerides (TG) stores build up in the insect fat body as lipid droplets at times of excess of food. The mobilization of fat body triglyceride (TG) is stimulated by adipokinetic hormones (AKH). The action of AKH involves a rapid activation of cAMP-dependent protein kinase (PKA). Recent in vitro studies have shown that PKA phosphorylates and activates the TG-lipase substrate, the lipid droplets. Conversely, purified TG-lipase from Manduca sexta fat body is phosphorylated by PKA in vitro but is not activated. This study was directed to learn whether or not AKH promotes a change in the state of phosphorylation of the lipase in vivo, and what are the relative contributions of cytosol and lipid droplets to the overall increase of lipolysis triggered by AKH. TG-lipase activity of fat body cytosols isolated from control and AKH-treated insects was determined against the native substrate, in vivo [3H]-TG radiolabeled lipid droplets, obtained from control and AKH-treated insects. The lipase activity of the system composed of AKH-cytosol and AKH-lipid droplets (11.1 +/- 2.1 nmol TG/min-mg) was 3.1-fold higher than that determined with control cytosol and lipid droplets (3.6 +/- 0.5 nmol TG/min-mg). Evaluation of the role of AKH-induced changes in the lipid droplets on lipolysis showed that changes in the lipid droplets are responsible for 70% of the lipolytic response to AKH. The remaining 30% appears to be due to AKH-dependent changes in the cytosol. However, the phosphorylation level of the TG-lipase was unchanged by AKH, indicating that phosphorylation of the TG-lipase plays no role in the activation of lipolysis induced by AKH.
The Main Triglyceride-lipase from the Insect Fat Body is an Active Phospholipase A(1): Identification and Characterization
Journal of Lipid Research. Dec, 2006 | Pubmed ID: 17005997
The main triglyceride-lipase (TG-lipase) from the fat body of Manduca sexta has been identified as the homolog of Drosophila melanogaster CG8552. This protein is conserved among insects and also shares significant sequence similarity with vertebrate phospholipases (PLs) from the phosphatidic acid preferring-phospholipase A1 (PA-PLA(1)) family. It is shown here that the TG-lipase is also a PL. TG-lipase and PL activities copurify and are inhibited by, or resistant to, the same lipase inhibitors, indicating that both activities are catalyzed by the same enzyme and active site. The PL activity of TG-lipase corresponded to PL type A(1). The concentration dependence of lipase activity with TG and PL micellar substrates showed saturation kinetics, with apparent K(m) values of 152 +/- 11 and 7.8 +/- 1.1 muM, respectively. TG-lipase was able to hydrolyze the major phospholipid components of the lipid droplets, phosphatidylcholine and phosphatidylethanolamine. The enzyme hydrolyzes 77 molecules of TG for every molecule of PL contained in the lipid droplets. It was observed that the activation of lipolysis in vivo is accompanied by activation of the hydrolysis of phospholipids of the lipid droplets. These results suggest that the PL activity of the insect TG-lipase could be required to allow access of the lipase to TG molecules contained in the core of the lipid droplets.
Over-expression of BMP4 and BMP5 in a Child with Axial Skeletal Malformations and Heterotopic Ossification: a New Syndrome
American Journal of Medical Genetics. Part A. Apr, 2007 | Pubmed ID: 17345627
Bone morphogenetic proteins (BMPs) are a highly conserved class of signaling molecules that induce ectopic cartilage and bone formation in vivo. Dysregulated expression of bone morphogenetic protein 4 (BMP4) is found in the cells of patients who have fibrodysplasia ossificans progressiva (FOP), a genetic disorder of axial and appendicular skeletal malformation and progressive heterotopic ossification. Loss of function mutations in the bone morphogenetic protein 5 (bmp5) gene leading to under-expression of BMP5 cause the murine short ear syndrome, characterized by small malformed ears and a broad range of axial skeletal malformations. We found features reminiscent of both the short ear mouse and FOP in a child with malformed external ears, multiple malformations of the axial skeleton, and progressive heterotopic ossification in the neck and back. We examined BMP mRNA expression in transformed lymphocytes by semi-quantitative RT-PCR and protein expression by ELISA assays and immunohistochemistry. Elevated levels of BMP4 and BMP5 mRNA and protein were detected in the patient's cells while levels of BMP2 mRNA were unchanged. Our data suggest that dysregulated expression of BMP4 and BMP5 genes is associated with an array of human axial skeletal abnormalities similar to the short ear mouse and FOP.
Low Incidence of Bovine Leukocyte Adhesion Deficiency (BLAD) Carriers in Indian Cattle and Buffalo Breeds
Journal of Applied Genetics. 2007 | Pubmed ID: 17495349
BLAD is an autosomal recessive genetic disease that affects Holstein-Friesian (HF) cattle worldwide. It is a disease characterized by a reduced expression of the adhesion molecules on neutrophils. The disease is caused by a mutation that replaces adenine at 383 with guanine, which causes an amino acid change from aspartic acid to glycine. Blood samples and a few semen samples were collected from 1250 phenotypically normal individuals, including HF (N=377), HF crossbred (N=334), Jersey (105), other breeds of cattle (N=160) and water buffalo Bubalus bubalis (N=274) belonging to various artificial insemination stations, bull mother farms (BMFs) and embryo transfer (ET) centres across the country. PCR-RFLP was performed to detect a point mutation in CD18, surface molecules of neutrophils. The results indicate that out of 1250 cattle and buffaloes tested for BLAD, 13 HF purebreds out of 377 and 10 HF crossbreds out of 334 appear to be BLAD carriers. In the HF and HF crossbred population, the percentage of BLAD carriers was estimated as 3.23%. The condition is alarming as the mutant gene has already entered the HF crossbred cattle population and therefore, the population of HF and its crossbreds needs regular screening to avoid the risk of spreading BLAD in the breeding cattle population of India.
Calcified Tissue International. Dec, 2007 | Pubmed ID: 18008019
Measurement of skin thickness has been proposed as a method of predicting low bone mineral density (BMD) and the consequent risk of osteoporotic fracture in postmenopausal women. The Episcan I-100 device is a new type of ultrasound device that uses high-frequency (20 MHz) ultrasound to measure skin thickness using a small probe placed on the skin. The aims of this study were to investigate whether there is any correlation between skin thickness as measured by ultrasound and BMD as measured by dual-energy X-ray absorptiometry, to establish whether patients with osteoporotic fractures have reduced skin thickness, and to investigate the relationship between skin thickness and clinical risk factors for osteoporosis. Short-term precision based on duplicate measurements on 132 patients gave a coefficient of variation of 3.2%. Small but statistically significant correlations between skin thickness measurements and BMD measurements at axial and peripheral sites were observed (r = 0.21-0.29, P < 0.0001). An odds ratio of 1.42 was found for identifying patients with a prevalent fracture at any skeletal site, suggesting that skin thickness measurements can discriminate patients with fractures. ROC analyses also demonstrated the ability of skin thickness measurements to discriminate fracture patients from controls. When measured by the decrease in Z-score, clinical risk factors for low BMD were found to affect skin thickness measurements to a similar extent as spine and hip BMD measurements. Skin thickness measurements have limited utility in identifying patients with low bone mass.
Field Induced Rotational Viscosity of Ferrofluid: Effect of Capillary Size and Magnetic Field Direction
Journal of Colloid and Interface Science. Jul, 2008 | Pubmed ID: 18452937
In the present investigation we report the effect of capillary diameter and the direction of applied magnetic field on the rotational viscosity of water and kerosene based ferrofluids. We found that changes in the field induced rotational viscosity are larger in the case of water based magnetic fluid than that of kerosene based fluid. The field induced rotational viscosity is found to be inversely proportional to the capillary diameter and it falls exponentially as a function of the angle between the direction of field and vorticity of flow. Magnetophoretic mobility and hydrodynamic volume fraction of nanomagnetic particles are determined for above cases.
Community Eye Health / International Centre for Eye Health. Mar, 2008 | Pubmed ID: 18504467
American Journal of Physiology. Endocrinology and Metabolism. Aug, 2008 | Pubmed ID: 18505833
Resistin has been linked to components of the metabolic syndrome, including obesity, insulin resistance, and hyperlipidemia. We hypothesized that resistin deficiency would reverse hyperlipidemia in genetic obesity. C57Bl/6J mice lacking resistin [resistin knockout (RKO)] had similar body weight and fat as wild-type mice when fed standard rodent chow or a high-fat diet. Nonetheless, hepatic steatosis, serum cholesterol, and very low-density lipoprotein (VLDL) secretion were decreased in diet-induced obese RKO mice. Resistin deficiency exacerbated obesity in ob/ob mice, but hepatic steatosis was drastically attenuated. Moreover, the levels of triglycerides, cholesterol, insulin, and glucose were reduced in ob/ob-RKO mice. The antisteatotic effect of resistin deficiency was related to reductions in the expression of genes involved in hepatic lipogenesis and VLDL export. Together, these results demonstrate a crucial role of resistin in promoting hepatic steatosis and hyperlipidemia in obese mice.
Polyethylene Glycol 400 Enhances the Bioavailability of a BCS Class III Drug (ranitidine) in Male Subjects but Not Females
Pharmaceutical Research. Oct, 2008 | Pubmed ID: 18600434
The aim of this study was to investigate the effects of different doses of polyethylene glycol 400 (PEG 400) on the bioavailability of ranitidine in male and female subjects.
Evaluation of Disease-specific Health-related Quality of Life in Patients with Pulmonary Arterial Hypertension
Respiratory Medicine. Oct, 2008 | Pubmed ID: 18617379
Pulmonary arterial hypertension (PAH) remains a debilitating and life-threatening disease despite improvements in hemodynamics, exercise capacity and survival with recent therapeutic advances. Health-related quality of life (HRQOL) has, therefore, been proposed as an important outcome for evaluating care. Relatively little, however, is known regarding HRQOL or its determinants in PAH. The Minnesota Living with Heart Failure questionnaire was recently adapted and validated for HRQOL measurement in PAH. We applied this pulmonary hypertension-specific version (MLHF-PH) to a larger population of PAH patients.
Drugs. 2008 | Pubmed ID: 18627208
Cigarette smoke, a toxic collection of more than 4000 chemicals generated from combustion of tobacco plant leaves, is known to cause several respiratory ailments, including chronic bronchitis, emphysema and lung cancer, and is associated with an increase in respiratory infections. In addition, cigarette smoking is considered a principal aetiological factor responsible for the development of certain diffuse interstitial and bronchiolar lung diseases, namely respiratory bronchiolitis-interstitial lung disease (RB-ILD), desquamative interstitial pneumonia (DIP) and adult pulmonary Langerhans' cell histiocytosis (PLCH). Although not exclusively seen in cigarette smokers, substantial clinical and epidemiological data support a central role for smoking as the primary causative agent of most RB-ILD, DIP and PLCH. Additional evidence in support of cigarette smoke as a primary aetiological agent in RB-ILD, DIP and PLCH is the observation that smoking cessation may lead to disease improvement, while recurrence of these disorders has been observed to occur in the transplanted lung upon re-exposure to tobacco smoke. Furthermore, histopathological changes of respiratory bronchiolitis, DIP and PLCH (with or without co-existent emphysema) may be found on lung biopsy in the same individual, implicating smoking as a common inciting agent of these diverse lesions. Recent studies also suggest a role for cigarette smoking as a potential co-factor in the development of acute eosinophilic pneumonia, usual interstitial pneumonia and rheumatoid arthritis-associated interstitial lung disease. In the current review, we propose a novel classification that takes into account the complex relationship between cigarette smoking and diffuse lung diseases. Investigation on the role of smoking as a potential causative factor or modifier of these diverse diffuse lung diseases is important, as smoking cessation utilizing state-of-the-art tobacco cessation efforts should be a central part of therapy, while pharmacotherapy with corticosteroids or other immune modifying agents should be reserved for selected patients.
Repulsion by Slit and Roundabout Prevents Shotgun/E-cadherin-mediated Cell Adhesion During Drosophila Heart Tube Lumen Formation
The Journal of Cell Biology. Jul, 2008 | Pubmed ID: 18663139
During Drosophila melanogaster heart development, a lumen forms between apical surfaces of contralateral cardioblasts (CBs). We show that Slit and its receptor Roundabout (Robo) are required at CB apical domains for lumen formation. Mislocalization of Slit outside the apical domain causes ectopic lumen formation and the mislocalization of cell junction proteins, E-cadherin (E-Cad) and Enabled, without disrupting overall CB cell polarity. Ectopic lumen formation is suppressed in robo mutants, which indicates robo's requirement for this process. Genetic evidence suggests that Robo and Shotgun (Shg)/E-Cad function together in modulating CB adhesion. robo and shg/E-Cad transheterozygotes have lumen defects. In robo loss-of-function or shg/E-Cad gain-of-function embryos, lumen formation is blocked because of inappropriate CB adhesion and an accumulation of E-Cad at the apical membrane. In contrast, shg/E-Cad loss-of-function or robo gain-of-function blocks lumen formation due to a loss of CB adhesion. Our data show that Slit and Robo pathways function in lumen formation as a repulsive signal to antagonize E-Cad-mediated cell adhesion.
Occult Malignancy in Patients with Suspected Paraneoplastic Neurologic Syndromes: Value of Positron Emission Tomography in Diagnosis
Mayo Clinic Proceedings. Mayo Clinic. Aug, 2008 | Pubmed ID: 18674476
To determine the value of positron emission tomography (PET) in diagnosing occult malignancies in patients with paraneoplastic neurologic syndromes (PNSs) at Mayo Clinic's site in Rochester, MN.
Optics Letters. Sep, 2008 | Pubmed ID: 18758587
An unusual emission of light is observed when a coherent light beam is passed through a mixture of a magnetorheological suspension and a ferrofluid that is subjected to a critical magnetic field. When first the incident light is removed and then the field is switched off, a flash of light is observed. In this Letter certain characteristics of this unusual emission are reported. Our findings suggest that a part of the incident light energy is magnetically trapped within the medium. Upon removal of the field, the same is released. Several physical phenomena that may give rise to such emission are discussed. The magnetically tunable emission will be useful to develop photonic devices.
Current Pharmaceutical Biotechnology. Oct, 2008 | Pubmed ID: 18855694
Advances in molecular biology and biochemistry have dramatically increased our understanding of disease. The molecular mechanisms are the pathogenic basis of disease is changing modern medicine. New drugs often inhibit specific key pathways. In nuclear medicine, molecular imaging agents have been used for years, but most contrast agents for MRI or CT today are unspecific. The diagnosis is based on alterations in morphology and basic physiology, all of which are late manifestations of the original molecular changes. There are only few more specific contrast agents available. Microbubbles are the one, of size of blood cells are used as contrast agents for ultrasound imaging and are particularly valuable for targeting selected tissues and for providing useful information about the efficacy of chemotherapy. The exploitation of microbubble agents can be achieved when there is a full understanding of the bubble/ultrasound interaction for microbubbles freely suspended in blood or attached to blood vessel walls. Microbubbles are promising tool for targeting chemotherapeutics, polypeptides and genetic material to its target in body.
The Correlation Between Phalangeal Quantitative Ultrasonography and Dual Energy X-ray Absorptiometry in Women with Premature Ovarian Failure
McGill Journal of Medicine : MJM : an International Forum for the Advancement of Medical Sciences by Students. Jul, 2008 | Pubmed ID: 19148311
With the growing demand for bone densitometry services there is a need for simple, cost-effective and ideally mobile devices which can identify individuals who are at risk of osteoporotic fracture. When new devices are evaluated, it is useful to examine the correlation with the established 'gold standard' technique of dual x-ray absorptiometry (DXA). This study examined the correlation between quantitative ultrasound (QUS) measurements performed at the phalanges and conventional DXA measurements of the spine and hip in women with premature ovarian failure--a known risk factor for osteoporosis.
Journal of Physics. Condensed Matter : an Institute of Physics Journal. May, 2008 | Pubmed ID: 21694245
Magnetically induced elongation of magnetic nanocomposite micelles is observed microscopically. The superparamagnetic particles of double-surfacted water based ferrofluid are incorporated in spherical micelles of cetyltrimethyl ammonium bromide (CTABr) mixed with sodium salicylate salt (NaSal). Under the application of an external magnetic field these spherical magnetic micelles deformed to ellipsoids. The shape distortion occurs instantaneously and disappears when the external field is removed. This magnetodeformational effect is analyzed using linear magnetization and Hookean elasticity.
Silencing of Elongation Factor-2 Kinase Potentiates the Effect of 2-deoxy-D-glucose Against Human Glioma Cells Through Blunting of Autophagy
Cancer Research. Mar, 2009 | Pubmed ID: 19244119
2-Deoxy-d-glucose (2-DG), a synthetic glucose analogue that acts as a glycolytic inhibitor, is currently being evaluated in the clinic as an anticancer agent. In this study, we observed that treatment of human glioma cells with 2-DG activated autophagy, a highly conserved cellular response to metabolic stress and a catabolic process of self-digestion of intracellular organelles for energy use and survival in stressed cells. The induction of autophagy by 2-DG was associated with activation of elongation factor-2 kinase (eEF-2 kinase), a structurally and functionally unique enzyme that phosphorylates eEF-2, leading to loss of affinity of this elongation factor for the ribosome and to termination of protein elongation. We also showed that inhibition of eEF-2 kinase by RNA interference blunted the 2-DG-induced autophagic response, resulted in a greater reduction of cellular ATP contents, and increased the sensitivity of tumor cells to the cytotoxic effect of 2-DG. Furthermore, the blunted autophagy and enhanced 2-DG cytotoxicity were accompanied by augmentation of apoptosis in cells in which eEF-2 kinase expression was knocked down. The results of this study indicate that the energy stress and cytotoxicity caused by 2-DG can be accelerated by inhibition of eEF-2 kinase, and suggest that targeting eEF-2 kinase-regulated autophagic survival pathway may represent a novel approach to sensitizing cancer cells to glycolytic inhibitors.
Current Drug Delivery. Jan, 2009 | Pubmed ID: 19418966
Mucoadhesive patch releasing the drug in the oral cavity at predetermined rate may present distinct advantages over traditional dosage forms such as tablets, gels and solutions. The present study was concerned with the preparation and evaluation of mucoadhesive buccal patches for the controlled systemic delivery of Salbutamol sulphate to avoid first pass hepatic metabolism. The developed patches were evaluated for the physicochemical, mechanical and drug release characteristics. The patches showed desired mechanical and physicochemical properties to withstand environment of oral cavity. The in-vitro release study showed that patches could deliver drug to the oral mucosa for a period of 7 h. the patches exhibited adequate stability when tested under accelerated conditions.
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics. Jul, 2009 | Pubmed ID: 19658750
Ferrofluid-based magnetorheological (MR) fluid is prepared by dispersing micron-size magnetic spheres in a ferrofluid. We report here the mechanism of chain formation in ferrofluid based MR fluid, which is quite different from conventional MR fluid. Some of the nanomagnetic particles of ferrofluid filled inside the microcavities are formed due to association of large particles, and some of them are attached at the end of large particles. Under rotating magnetic field, fragmentation of a single chain into three parts is observed. Two of them are chains of micron-size magnetic particles which are suspended in a ferrofluid, and the third one is the chain of nanomagnetic particles of ferrofluid, which may be the connecting bridge between the two chains of larger magnetic particles. The rupture of a single chain provides evidence for the presence of nanomagnetic particles within the magnetic field-induced chainlike structure in this bidispersed MR fluid.
The American Journal of the Medical Sciences. Jan, 2009 | Pubmed ID: 18941405
Welding involves exposure to fumes, gases, radiation, electricity, noise, and heat. Herein, we describe 2 welders presenting with lung infiltrates and elevated liver enzyme levels. Both of these patients had pulmonary siderosis ("welder's lung") on lung biopsy along with evidence of systemic iron overload. Evaluation for genetic hemochromatosis and other known causes of iron overload was unrevealing. Welding with chronic inhalation of iron particles maybe an under-recognized source of systemic iron overload.
DNA Condensation by Chiral Alpha-methylated Polyamine Analogues and Protection of Cellular DNA from Oxidative Damage
Biomacromolecules. Jan, 2010 | Pubmed ID: 19919070
Polyamines are essential molecules supporting the structure, conformation, and function of nucleic acids and proteins. We studied stereoisomers of alpha,alpha'-dimethylated spermine [(R,R)-Me(2)Spm, (S,S)-Me(2)Spm, (R,S)-Me(2)Spm] for their ability to provoke DNA condensation and protect DNA from damage. (R,R)- and (R,S)-Me(2)Spm displayed more efficient condensing ability than spermine, with significantly lower EC(50) (concentration for 50% compaction) values (p < or = 0.01). However, spermine exerted slightly more duplex stabilization than Me(2)Spm. Condensation resulted in nanoparticles with hydrodynamic radii between 39.6 and 48.4 nm, and electron microscopy showed the presence of toroids and spheroids. Natural polyamines and stereoisomers of Me(2)Spm protected DNA against DNase digestion and oxidative stress in vitro and against etoposide and oxidative stress in DU145 cells but afforded little protection against UV-C irradiation. Our findings indicate that Me(2)Spm stereoisomers are efficient DNA packaging agents with potential applications in gene delivery. Our study also reveals stereospecificity in DNA interaction and protection against cellular stress.
Mobilization of Lipid Stores in Manduca Sexta: CDNA Cloning and Developmental Expression of Fat Body Triglyceride Lipase, TGL
Insect Biochemistry and Molecular Biology. Feb, 2010 | Pubmed ID: 20060045
Fatty acids stored as triglycerides (TG) in the fat body serve as precursor in multiple processes including energy production and synthesis of cellular components. Mobilization of fatty acids from TG depends on the action of lipases. The fat body triglyceride lipase from Manduca sexta, MsTGL, is the only insect lipase that has been purified and characterized, so far. A TGL cDNA from M. sexta fat body encoding a 649 amino acid protein was cloned and its identity confirmed by mass spectrometry and Edman sequencing data of the purified protein. The protein sequence has conserved domains and residues of potential importance for the function and regulation of TGL activity. The expression of TGL and the lipase activity of fat body homogenates were studied in several developmental stages of M. sexta. TG-hydrolase activity of fat body increased as larva grew to the last instar and, then, decreased to minimal levels during pupa stage. Lipase activity was progressively restored in adult insects and reached maximum values at this stage. The fat body lipase activity from adult insects, 1-2 day after emergence, was 9-fold higher than that from 2 to 3 days old 5th-instar larvae. A good correlation was found between the abundance of TGL protein and the lipase activity of fat body homogenates. This correlation and the expression pattern of TGL throughout development are consistent with the notion that TGL is the main fat body TG lipase of M. sexta.
Journal of Endourology / Endourological Society. Apr, 2010 | Pubmed ID: 20218892
The objective of this study was to assess the face, content, construct, convergent, and predictive validities of virtual reality-based simulator in acquisition of skills for percutaneous renal access.
Journal of the Optical Society of America. A, Optics, Image Science, and Vision. Apr, 2010 | Pubmed ID: 20360829
Mie scattering functions for a magnetizable sphere whose relative refractive index is dependent on the externally applied magnetic field are computed for four different sizes of the sphere. It is found that Mie resonances are observed at certain critical fields when the incident light is polarized with its electric vector perpendicular to the applied field. The width of resonance as well as the critical fields shifts with the increase in size of the spheres. Results are compared with the experimentally observed scattering effects in a dispersion of magnetite spheres in a ferrofluid.
Journal of Clinical Densitometry : the Official Journal of the International Society for Clinical Densitometry. Jul-Sep, 2010 | Pubmed ID: 20554233
Because osteoporosis is common and usually managed in primary care, there is a requirement for cheap and convenient methods of measuring bone mineral density (BMD). AccuDEXA (Lone Oak Medical Technologies, Doylestown, PA) is a tabletop dual-energy X-ray absorptiometry (DXA) device that performs BMD measurements of the hand in the middle phalanges of the third finger. The aims of this study were to (1) evaluate the use of AccuDEXA in UK women; (2) investigate the concordance between AccuDEXA T-scores and DXA T-scores for central (spine and hip) sites; (3) investigate the comparative response of AccuDEXA measurements to clinical risk factors for osteoporosis. Measurements of phalangeal and central BMD were performed in 620 women referred by their family doctors for bone densitometry (group 1) and 159 healthy female volunteers (group 2). For 65 women in group 2, aged 39 yr or younger, the mean Z-scores for AccuDEXA and the central sites calculated from US reference ranges were consistent with the expected value of 0, whereas for the 62 group 2 women, aged 50 yr or older, the mean Z-scores for AccuDEXA and the central sites were in the range 0.4-0.7 and were statistically significantly different from 0. In both group 1 and group 2, the AccuDEXA T-scores in older and younger women were systematically higher than those in the central sites by up to 1 unit. Of the 157 women aged 50 yr or older, with osteoporosis, based on their central DXA results, only 34 (22%) had an AccuDEXA T-score less than or equal to -2.5, whereas 76 (48%) had osteopenia and 47 (30%) were normal based on their AccuDEXA T-scores. When assessed by the effect of clinical risk factors on Z-scores, both AccuDEXA and central BMD were affected to a similar extent. We conclude that the conventional World Health Organisation T-score criteria for the diagnosis of osteoporosis should not be applied to AccuDEXA measurements in UK women. Clinical risk factors for low BMD were found to affect AccuDEXA measurements to a similar extent as central BMD measurements. AccuDEXA measurements could, therefore, provide an alternative method for identifying individuals with low bone mass, provided care is taken in interpreting T-scores, perhaps, through the use of device-specific thresholds.
Chemical Communications (Cambridge, England). Aug, 2010 | Pubmed ID: 20593086
1-Chloro-2,3-diphenylcyclopropenium ion was found to be a very efficient organocatalyst (3 mol% loading) for liquid phase Beckmann rearrangement of various ketoximes to the corresponding amides/lactams within 2 h in acetonitrile at reflux temperature. This is the first example of the application of the cyclopropenium ion as a catalyst, which opens up a new aspect of the synthetic utility of aromatic cation based catalysis.
Bone. Nov, 2010 | Pubmed ID: 20699129
Osteoporotic patients treated with strontium ranelate show relatively large increases in bone mineral density (BMD) measured by dual-energy X-ray absorptiometry (DXA) due to the replacement of some of the calcium atoms in bone by strontium. A study published by Pors Nielsen and colleagues reported that replacement of 1% of calcium atoms by strontium causes a 10% increase in BMD. We refer to the ratio of the percentage increase in BMD to the molar percentage of strontium in bone as the strontium ratio. Theoretically it is expected that the strontium ratio should vary between different manufacturers' DXA equipment depending on the effective photon energy of the device, an effect that arises because of the proximity of the X-ray energies produced by lower energy devices to the strontium K-edge at 16 keV. In this study we report theoretical estimates of the strontium ratio for two axial DXA systems and two peripheral DXA devices based on their broad spectrum X-ray emission. The theoretical figures were verified in an experimental study in which the strontium ratio for each device was measured using phantoms containing mixtures of hydroxyapatite and strontium hydrogen-phosphate. The theoretical values of the strontium ratio were 11.0 for the Hologic Discovery, 9.9 for the GE-Lunar Prodigy, 9.1 for the Demetech Calscan, and 8.5 for the Osteometer Dexacare G4. Experimental results were 11.2 for the Discovery, 9.9 for the Prodigy, 8.6 for the Calscan and 6.3 for the Dexacare G4. The results confirm both theoretically and experimentally that the effect of bone strontium on BMD measurements is different for different DXA systems. In the future it might be possible to exploit this effect to make a non-invasive estimate of average bone strontium content in groups of patients receiving strontium medication for osteoporosis.
In Vitro Cytotoxicity Study of Agave Americana, Strychnos Nuxvomica and Areca Catechu Extracts Using Mcf-7 Cell Line
Journal of Advanced Pharmaceutical Technology & Research. Apr, 2010 | Pubmed ID: 22247852
Research is focusing on the search for new types of natural chemotherapeutic agent that is plant based medicines which are proving to be excellent sources of new compounds. In present research study, an attempt was made to prove cytotoxicity activity of various parts of medicinal plants such as Agave americana, Strychnos nuxvomica and Areca catechu using MCF-7 and Vero cell line. Various parts of the medicinal plants were extracted by soxhlet apparatus using solvents likes methanol and water. By trypan blue dye exclusion method, Viability of MCF-7 and Vero cell lines were 85.50 and 81.13%, respectively. IC(50) value of methanol extract of Agave americana leaves and aqueous extract of Areca catechu fruits were found to be 545.9 & 826.1 μg/ml by SRB assay and 775.1 & 1461pg/ml by MTT assay, respectively, against MCF-7 cell line. From cytotoxicity study data by SRB and MTT assay, it revealed that methanol extract of Agave americana and aqueous extract of Areca catechu are potent cytotoxic.
Endocrine. Oct, 2011 | Pubmed ID: 21842289
Type 2 diabetes mellitus (T2DM) is a major health priority globally, having achieved pandemic status in the twenty-first century. Several gastrointestinal procedures that were primarily designed to treat morbid obesity result in dramatic remission of diabetes. Studies in experimental rodent models and humans have shown that the glycemic benefits of surgery are at least in part weight-independent and extend to non-morbidly obese subjects with T2DM. Bariatric procedures differ in their ability to ameliorate type 2 diabetes, with intestinal bypass procedures being more effective than purely restrictive procedures. Several studies have demonstrated that the benefits of bariatric surgery extend beyond amelioration of hyperglycemia and include improvement in other cardiovascular risk factors such as dyslipidemia and hypertension. The safety and cost-effectiveness of bariatric surgery are also well established by several studies. In this paper, the authors present the surgeon perspective on the management of type 2 diabetes focusing on the efficacy, safety and cost-effectiveness of metabolic surgery. The available evidence warrants the inclusion of metabolic surgery in the treatment algorithm of type 2 diabetes.
European Journal of Medicinal Chemistry. Oct, 2011 | Pubmed ID: 21875762
New chiral V(V) Schiff base complexes (S)-[VO(OMe)L] and (R)-[VO(OMe)L] were synthesized and characterized by microanalysis, infrared (IR), UV-Visible, Circular dichroism (CD) spectroscopy and single crystal X-ray studies. The interaction of these complexes with calf thymus (CT) DNA and bovine serum albumin (BSA) protein showed chiral expression DNA/protein binding strength. The influence of chirality was also observed in cytotoxicity assay of Hep 2 cells. (R)-[VO(OMe)L] enantiomer exhibited higher binding constant (5 ± 1 × 10(5) M(-1)) as compared to (S)-[VO(OMe)L] (8 ± 1 × 10(4) M(-1)). The fluorescence quenching, thermal melting and viscosity data suggest DNA surface and/or groove binding nature of the complexes and electrophoresis studies also showed greater activity for (R)-[VO(OMe)L] in cleaving DNA and protein as against (S)-[VO(OMe)L].
Respirology (Carlton, Vic.). Nov, 2011 | Pubmed ID: 22085242
SUMMARY AT A GLANCE: The causes of death in patients with inflammatory myopathies have not been extensively evaluated. We reviewed autopsy data from patients with inflammatory myopathies seen at our institution and show that respiratory complications are common and often unsuspected causes of death. ABSTRACT: Background and objective Polymyositis (PM) and dermatomyositis (DM) are idiopathic inflammatory myopathies that are associated with a variety of clinical manifestations including pulmonary complications. The objective of the present study was to determine the causes of deaths in this complex patient population. Methods A computer-assisted search of medical and autopsy records identified a total of 39 patients with either PM or DM who underwent an autopsy at the Mayo Clinic (Rochester, MN, USA) over a 29-year period from January 1(st) , 1981 to December 31(st) , 2009. The immediate causes of death along with contributing causes were determined by reviewing all available clinical data and autopsy findings. We also analyzed the discordance between antemortem clinical diagnoses provided by clinicians and the final diagnosis by the postmortem analysis. Results Respiratory (33%), infectious (28%), and cardiovascular diseases (26%) accounted for the majority of immediate causes of death. Acute exacerbation of chronic interstitial lung disease (15%) and bronchopneumonia (15%) were the most common specific causes. Immediate cause of death was not suspected in nearly one-third of cases and included bronchopneumonia, sepsis, acute myocardial infarction, aspiration pneumonia, pulmonary embolism, aortic stenosis, mycotic aneurysm rupture, and acute hemoperitoneum. Conclusions We conclude that pulmonary injury is the immediate cause of death in one-third of patients with PM/DM; acute exacerbation of chronic interstitial lung disease and bronchopneumonia were the most common specific causes. Immediate cause of death was not established antemortem in nearly one-third of cases and some of these causes were treatable.
Applied Optics. Nov, 2011 | Pubmed ID: 22086041
A ferrodispersion, which comprises micrometer-sized magnetizable spheres dispersed in a ferrofluid, is shown to store retrievable optical energy. It is observed that when such dispersion is subjected to a transverse magnetic field and a linearly polarized monochromatic light with its electric vector perpendicular to the applied field is incident on it, then for a critical static magnetic field of moderate intensity the emerging light disappears. Upon removing the light and then switching off the field, again light of the same frequency and same state of polarization reappears. A time delay between emission of the light and switching off the field is observed. The statistical distribution of this delay is reported. Intensity of the retrieval signal is found to depend on the storage time. This effect is investigated. Storing and retrieval of optical energy will be useful for developing a magnetically tunable optical capacitor.
Respiratory Medicine. Jan, 2011 | Pubmed ID: 21036585
Hypereosinophilic syndromes (HES) are a heterogeneous group of conditions that are characterized by tissue-associated eosinophilic inflammation and peripheral eosinophilia. Although clinical and radiologic features associated with most forms of eosinophilic lung diseases are relatively well-described, there is little known regarding lung involvement in HES. The aims of the present study were to ascertain the frequency of pulmonary involvement in HES and define associated clinical and radiologic features.
EEF-2 Kinase Dictates Cross-talk Between Autophagy and Apoptosis Induced by Akt Inhibition, Thereby Modulating Cytotoxicity of Novel Akt Inhibitor MK-2206
Cancer Research. Apr, 2011 | Pubmed ID: 21307130
Inhibition of the survival kinase Akt can trigger apoptosis, and also has been found to activate autophagy, which may confound tumor attack. In this study, we investigated regulatory mechanisms through which apoptosis and autophagy were modulated in tumor cells subjected to Akt inhibition by MK-2206, the first allosteric small molecule inhibitor of Akt to enter clinical development. In human glioma cells, Akt inhibition by MK-2206 or siRNA-mediated attenuation strongly activated autophagy, whereas silencing of eukaryotic elongation factor-2 (eEF-2) kinase, a protein synthesis regulator, blunted this autophagic response. Suppression of MK-2206-induced autophagy by eEF-2 silencing was accompanied by a promotion of apoptotic cell death. Similarly, siRNA-mediated inhibition of eEF-2 kinase potentiated the efficacy of MK-2206 against glioma cells. Together, these results showed that blunting autophagy and augmenting apoptosis by inhibition of eEF-2 kinase could modulate the sensitivity of glioma cells to Akt inhibition. Our findings suggest that targeting eEF-2 kinase may reinforce the antitumor efficacy of Akt inhibitors such as MK-2206.
International Journal of Pharmaceutics. May, 2011 | Pubmed ID: 21382460
Previous in vivo studies using PEG 400 showed an enhancement in the bioavailability of ranitidine. This study investigated the effect of PEG 200, 300 and 400 on ranitidine transport across Caco-2 cells. The effect of PEG polymers (20%, v/v) on the bi-directional flux of (3)H-ranitidine across Caco-2 cell monolayers was measured. The concentration dependence of PEG 400 effects on ranitidine transport was also studied. A specific screen for P-glycoprotein (P-gp) activity was used to test for an interaction between PEG and P-gp. In the absence of PEG, ranitidine transport showed over 5-fold greater flux across Caco-2 monolayers in the secretory than the absorptive direction; efflux ratio 5.38. PEG 300 and 400 significantly reduced this efflux ratio (p<0.05), whereas PEG 200 had no effect (p>0.05). In concordance, PEG 300 and 400 showed an interaction with the P-gp transporter, whereas PEG 200 did not. Interestingly, with PEG 400 a non-linear concentration dependence was seen for the inhibition of the efflux ratio of ranitidine, with a maxima at 1%, v/v (p<0.05). The inhibition of ranitidine efflux by PEG 300 and 400 which interact with P-gp provides a mechanism that may account for the observations of ranitidine absorption enhancement by PEG 400 in vivo.
Variation in the Genetic Environments of Bla(CTX-M-15) in Escherichia Coli from the Faeces of Travellers Returning to the United Kingdom
The Journal of Antimicrobial Chemotherapy. May, 2011 | Pubmed ID: 21393166
The genetic surroundings of bla(CTX-M-15) in Escherichia coli recovered from faeces of travellers returning to the UK from overseas were compared with those among established UK strains to provide further insights into the spread of bla(CTX-M-15) in the UK.
Relative Quantification of Polyethylene Glycol 400 Excreted in the Urine of Male and Female Volunteers by Direct Injection Electrospray-selected Ion Monitoring Mass Spectrometry
International Journal of Pharmaceutics. Jul, 2011 | Pubmed ID: 21557993
The use of polyethylene glycol 400 (PEG 400) as an excipient in oral formulations can have profound and differing effects on drug bioavailability in men and women; therefore an understanding of the pharmacokinetics of this excipient is required. A direct injection electrospray selected ion monitoring mass spectrometry methodology was developed and validated for the quantitation of PEG 400 excreted in human urine after oral administration. The most abundant ions corresponding to PEG 400 oligomers at m/z 365, 409, 453, 497, 541, and 585 were used for selected ion monitoring (SIM). Pre-dose urine of volunteers was spiked with various amounts of PEG 400 to generate calibration curves over the concentration range 2.5-90 μg/mL for all SIM channels. The relative standard deviations of intra- and inter-day analysis of PEG 400 in human urine were lower than 11.8% and bias percentage was less than 9.7%. This specific method for relative quantitation of PEG 400 was then used to analyse urine samples with minimal sample preparation. Urine samples of twelve healthy volunteers (six men and six women) who received 0.75 g and 1.5 g PEG 400 on two separate occasions were collected over 24h. On average 36.5% of the orally administered dose of PEG 400 was recovered in the urine of the volunteers, with no significant difference observed between men and women.
Journal of Clinical Monitoring and Computing. Apr, 2011 | Pubmed ID: 21638068
Many cases of malignant hyperthermia triggered by volatile anesthetic agents have been described. However, to our knowledge, there has not been a report describing the precise changes in physiologic data of a human suffering from this process. Here we describe a case of malignant hyperthermia in which monitoring information was frequently and accurately captured by an anesthesia information management system.
A Potential Estrogen Mimetic Effect of a Bis(ethyl)polyamine Analogue on Estrogen Receptor Positive MCF-7 Breast Cancer Cells
Amino Acids. Feb, 2012 | Pubmed ID: 21830120
BE-3-3-3-3 (1,15-(ethylamino)4,8,12-triazapentadecane) is a bis(ethyl)polyamine analogue under investigation as a therapeutic agent for breast cancer. Since estradiol (E(2)) is a critical regulatory molecule in the growth of breast cancer, we examined the effect of BE-3-3-3-3 on estrogen receptor α (ERα) positive MCF-7 cells in the presence and absence of E(2). In the presence of E(2), a concentration-dependent decrease in DNA synthesis was observed using [(3)H]-thymidine incorporation assay. In the absence of E(2), low concentrations (2.5-10 μM) of BE-3-3-3-3 increased [(3)H]-thymidine incorporation at 24 and 48 h. BE-3-3-3-3 induced the expression of early response genes, c-myc and c-fos, in the absence of E(2), but not in its presence, as determined by real-time quantitative polymerase chain reaction (qPCR). BE-3-3-3-3 had no significant effect on these genes in an ERα-negative cell line, MDA-MB-231. Chromatin immunoprecipitation assay demonstrated enhanced promoter occupation by either E(2) or BE-3-3-3-3 of an estrogen-responsive gene pS2/Tff1 by ERα and its co-activator, steroid receptor co-activator 3 (SRC-3). Confocal microscopy of BE-3-3-3-3-treated cells revealed membrane localization of ERα, similar to that induced by E(2). The failure of BE-3-3-3-3 to inhibit cell proliferation was associated with autophagic vacuole formation, and the induction of Beclin 1 and MAP LC3 II. These results indicate a differential effect of BE-3-3-3-3 on MCF-7 cells in the absence and presence of E(2), and suggest that pre-clinical and clinical development of polyamine analogues might require special precautions and selection of sensitive subpopulation of patients.