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1.
Kathmandu Univ Med J (KUMJ) ; 17(58): 117-120, 2017.
Article in English | MEDLINE | ID: mdl-34547841

ABSTRACT

Background The Lagenaria siceraria (Molina) belongs to family Cucurbitaceae, commonly known as bottle guard or calabash in English. All the parts of plant like root, fruit, leaves and flower has been evaluated for its various activities like antioxidant, antihelmintic, cognitive enhancer, anticancer, antianxiety, antidepressant, antihyperlipidemic, fibrinolytic cardio protective and hepatoprotective. Even though it is claimed to have antiepileptic action, no documentation is available. Objective To assess the anticonvulsant activity of aqueous extract of Lagenaria siceraria by Maximal Electroshock seizure induced seizure models on Albino rats. Method Albino rats were taken and divided into five groups, each consisting of five rats. One group was used as control (normal saline 10 ml/kg), one as standard (phenytoin), and three groups for the test drug (aqueous extract of Lagenaria siceraria (AELS) in the doses of 200, 400 and 800 mg/kg) treatment. In MES model, Maximal electrical shock of 150 mA was passed for 0.2 seconds through corneal electrodes after 30 minutes of giving the drugs and normal saline. Different stages of convulsions were noted down along with time spent by the animal in each phase of convulsions. Data were statistically analyzed by One way ANOVA followed by multiple Dunnett's test. Result The mean reduction in hind limb extension phase was 8.2±2.10 after 400 mg/kg of AELS which is highly significant (p<0.001) like phenytoin. AELS at 800 mg/kg exhibited a significant 17±2.64 (p<0.05) protection against tonic extensor phase. Conclusion Aqueous extract of Lagenaria siceraria has anticonvulsant activity.

2.
Leukemia ; 31(5): 1154-1165, 2017 05.
Article in English | MEDLINE | ID: mdl-27748372

ABSTRACT

Tumor necrosis factor-α (TNF-α)-induced RIP1/RIP3 (receptor-interacting protein kinase 1/receptor-interacting protein kinase 3)-mediated necroptosis has been proposed as an alternative strategy for treating apoptosis-resistant leukemia. However, we found that most acute myeloid leukemia (AML) cells, especially M4 and M5 subtypes, produce TNF and show basal level activation of RIP1/RIP3/MLKL signaling, yet do not undergo necroptosis. TNF, through RIP1/RIP3 signaling, prevents degradation of SOCS1, a key negative regulator of interferon-γ (IFN-γ) signaling. Using both pharmacologic and genetic assays, we show here that inactivation of RIP1/RIP3 resulted in reduction of SOCS1 protein levels and partial differentiation of AML cells. AML cells with inactivated RIP1/RIP3 signaling show increased sensitivity to IFN-γ-induced differentiation. RIP1/RIP3 inactivation combined with IFN-γ treatment significantly attenuated the clonogenic capacity of both primary AML cells and AML cell lines. This combination treatment also compromised the leukemogenic ability of murine AML cells in vivo. Our studies suggest that inhibition of RIP1/RIP3-mediated necroptotic signaling might be a novel strategy for the treatment of AML when combined with other differentiation inducers.


Subject(s)
Cell Differentiation , Leukemia, Myeloid, Acute/pathology , Nuclear Pore Complex Proteins/metabolism , RNA-Binding Proteins/metabolism , Receptor-Interacting Protein Serine-Threonine Kinases/metabolism , Signal Transduction/drug effects , Apoptosis/drug effects , Cell Differentiation/drug effects , Humans , Interferon-gamma/pharmacology , Leukemia, Myeloid, Acute/drug therapy , Nuclear Pore Complex Proteins/antagonists & inhibitors , RNA-Binding Proteins/antagonists & inhibitors , Receptor-Interacting Protein Serine-Threonine Kinases/antagonists & inhibitors , Tumor Cells, Cultured , Tumor Necrosis Factor-alpha/pharmacology
3.
Br Dent J ; 217(2): E4, 2014 Jul.
Article in English | MEDLINE | ID: mdl-25060479

ABSTRACT

OBJECTIVE: To assess the level of knowledge and reporting of adverse drug reactions (ADRs) of dentists at different stages of their careers and conduct a training need analysis. DESIGN: Structured questionnaires were distributed to final year dental students (DSs), foundation year one students (DF1s) and general dental practitioners (GDPs). SETTING: Opportunity samples of DSs from Kings College London, DF1s from the postgraduate deaneries of Kent, Surrey and Sussex, and Oxford and GDPs in Hampshire and the Isle of Wight. The study was conducted from November 2012 to February 2013. MAIN OUTCOME MEASURES: Relative knowledge and awareness of ADRs and ADR reporting, and performance in an assessment of these aspects. RESULTS: Thirty-one DSs, 35 DF1s and 98 GDPs took part in the study. Awareness of the Yellow Card Scheme varied between groups (30.8%, 48.6% and 88.8% respectively). Reported use of the scheme was uniformly low (2.6%, 5.7% and 5.1% respectively). There were no differences in knowledge about ADRs and ADR reporting between the three groups of dentists as indicated by median scores achieved in the questionnaire test (54%, 73% and 62% for DSs, DF1s and GDPs respectively; p = 0.638). All of the DSs, 91.4% of DF1s and 91.8% of GDPs said that they would welcome further training. Key topics included training on ADRs to medicines commonly used in their dental practice and deciding what ADRs needed to be reported. The most popular format for delivery of this training was formal lectures for DF1s and GDPs, but workshops for DSs. Postgraduate deaneries were the most popular provider choice for DF1s and GDPs. CONCLUSIONS: Dentists at different stages of their careers showed variable awareness and knowledge of the UK Yellow Card Scheme and what to report. Training should be tailored to fit the needs of the different groups. A questionnaire survey incorporating a summative knowledge assessment demonstrated variable levels of knowledge about adverse drug reactions and what to report. Large majorities of all groups (>90%) expressed a desire for training in these areas and in the case of graduate and practising dentists, indicated that this should be organised by the postgraduate deaneries.


Subject(s)
Adverse Drug Reaction Reporting Systems , Dentists , Health Knowledge, Attitudes, Practice , Adult , England , Female , General Practice, Dental , Humans , Male , Students, Dental , Surveys and Questionnaires
4.
ISRN Pharm ; 2012: 528079, 2012.
Article in English | MEDLINE | ID: mdl-22852100

ABSTRACT

Conventional drug delivery systems are known to provide an immediate release of drug, in which one can not control the release of the drug and can not maintain effective concentration at the target site for longer time. Controlled drug delivery systems offer spatial control over the drug release. Osmotic pumps are most promising systems for controlled drug delivery. These systems are used for both oral administration and implantation. Osmotic pumps consist of an inner core containing drug and osmogens, coated with a semipermeable membrane. As the core absorbs water, it expands in volume, which pushes the drug solution out through the delivery ports. Osmotic pumps release drug at a rate that is independent of the pH and hydrodynamics of the dissolution medium. The historical development of osmotic systems includes development of the Rose-Nelson pump, the Higuchi-Leeper pumps, the Alzet and Osmet systems, the elementary osmotic pump, and the push-pull system. Recent advances include development of the controlled porosity osmotic pump, and systems based on asymmetric membranes. This paper highlights the principle of osmosis, materials used for fabrication of pumps, types of pumps, advantages, disadvantages, and marketed products of this system.

5.
Drug Dev Ind Pharm ; 37(10): 1244-52, 2011 Oct.
Article in English | MEDLINE | ID: mdl-21466414

ABSTRACT

The goal of diabetes therapy today is to achieve and maintain as near normal glycemia as possible to prevent the long-term microvascular and macrovascular complications of an elevated blood glucose. A newly developed inlay osmotic pump tablet (IOPT) can deliver glipizide (GLZ) and metformin HCl (MET) gradually in controlled manner. The aim of present investigation was to prepare the IOPT that can deliver >75% of GLZ in 2 h, whereas MET released after 2 h and sustained up to 12 h. In the present work, HP-ß-CD was used to modify the solubility of GLZ before incorporating in the osmotic system and MET was spray-dried with HPMC A15C to modify its release profile, flow property, and compressibility. Various parameters mainly G(75%) (75% GLZ release), t(LMET) (lag time of MET release from device), Q(10 h) (percent of MET released within 10 h), and RSQ(ZERO) (R(2) of release data fitted to zero-order equation) were used to compare different formulations. The effects of different formulation variables, that is, osmagents, concentration of hydrophilic polymer, diameter of drug releasing orifice, and coating composition on the drug release profile were investigated. The release rate of GLZ could be effectively modified by the addition of sodium carbonate and sodium chloride, whereas the release rate of MET was adjusted by dual-coating system and by addition of hydrophilic polymer. The developed inlay osmotic system could be effective in the multidrug therapy of diabetes by delivering both drugs in a controlled manner.


Subject(s)
Diabetes Mellitus, Type 2/drug therapy , Drug Delivery Systems , Glipizide/administration & dosage , Hypoglycemic Agents/administration & dosage , Metformin/administration & dosage , Tablets , Chemistry, Pharmaceutical , Delayed-Action Preparations/chemistry , Delayed-Action Preparations/therapeutic use , Drug Combinations , Humans , Osmosis , Particle Size , Solubility
6.
Indian J Pharm Sci ; 72(3): 290-4, 2010 May.
Article in English | MEDLINE | ID: mdl-21188035

ABSTRACT

Cyclin-dependent kinases are most extensively studied targets for cancer chemotherapy since the tumor cells exhibit false checkpoints and can proliferate even if the genome is compromised. Cyclin-dependent kinases ensure the tight regulation of the cell cycle execution by mediating phosphorylation of cellular proteins. Deregulation of the cyclin-dependent kinase 2 activity by cellular and external factors leads to many diseases like cancers. Different methods like radiolabeled, fluorescence and luminescence are available for screening of library of compounds against kinases. However, bioluminescent methods offer several advantages like low background and no effect of fluorescent compound interference. Present study is focused on development, optimization and validation of cyclin-dependent kinase 2 assay which is suitable for identification potent and selective, ATP competitive and non-competitive inhibitors of cyclin-dependent kinase 2. The aim of present investigation was to optimize the assay for cyclin-dependent kinase 2/cylin A and cyclin-dependent kinase 2/cyclin E with use of bioluminescence based biochemical reaction. Both cyclin-dependent kinase 2 which are cyclin-dependent kinase 2/cyclin A and cyclin-dependent kinase 2/cyclin E complexes, have different affinity for ATP. Therefore, both isoform analogs of cyclin-dependent kinase 2 were optimized separately. Optimum cyclin-dependent kinase 2/cyclin A and cyclin-dependent kinase 2/cyclin E concentration were found to be 250 ng/well and 200 ng/well, respectively. Optimum substrate (histone H1) concentration was found to be 2.5 mg/ml for both cyclin-dependent kinase 2 analogs. Optimum reaction time was found to be 20 min for both cyclin-dependent kinase 2/cyclin complexes.

7.
Curr Drug Deliv ; 7(4): 329-33, 2010 Oct.
Article in English | MEDLINE | ID: mdl-20695844

ABSTRACT

The purpose of the present study was to explore the combined effect of chemical enhancers and iontophoresis on the in vitro permeation of acyclovir gel across porcine skin. Acyclovir gel was formulated using carbopol 940 and hydroxypropyl methylcellulose K4M (HPMC K4M). Effect of drug concentration on the delivery of acyclovir was examined. Increasing drug concentration of acyclovir enhanced its flux across the skin. Incorporation of permeation enhancers (menthol, n-methyl-2-pyrrolidone and polyethylene glycol 400) into the gel resulted in enhanced acyclovir permeation when combined with iontophoresis. Menthol showed the highest drug permeation and when combined with iontophoresis it significantly increased the acyclovir skin permeation.


Subject(s)
Acyclovir/administration & dosage , Adjuvants, Pharmaceutic/pharmacology , Chemistry, Pharmaceutical/methods , Gels/administration & dosage , Iontophoresis/methods , Skin Absorption/drug effects , Acrylic Resins/administration & dosage , Acyclovir/pharmacokinetics , Adjuvants, Pharmaceutic/administration & dosage , Animals , Dose-Response Relationship, Drug , Hypromellose Derivatives , Menthol/administration & dosage , Menthol/pharmacology , Methylcellulose/administration & dosage , Methylcellulose/analogs & derivatives , Polyethylene Glycols/administration & dosage , Polyethylene Glycols/pharmacology , Pyrrolidinones/administration & dosage , Pyrrolidinones/pharmacology , Swine
8.
J Infect Dis ; 200 Suppl 1: S248-53, 2009 Nov 01.
Article in English | MEDLINE | ID: mdl-19817605

ABSTRACT

Rotavirus is the most common cause of fatal childhood diarrhea worldwide. We provide the first estimates of the health care and economic burden of severe rotavirus disease in Oman. We conducted active, hospital-based surveillance of rotavirus disease at 11 regional public hospitals in Oman, using the guidelines suggested by the generic World Health Organization protocol. From July 2006 through June 2008, all children aged <5 years who were hospitalized for acute gastroenteritis were enrolled in the surveillance program, and their stool samples were tested for rotavirus using a commercially available enzyme immunoassay (ID EIA Rotavirus Test; Dako Diagnostics). Rotavirus was detected in samples from 1712 (49%) of 3470 children. These children were hospitalized for a median of 3 days for severe diarrhea. A marked seasonal peak was evident with a majority of the cases occurring from December through May. Of the rotavirus cases, 69% occurred in children aged 6-17 months. We identified a diverse strain pattern in Oman, with G2 (37%), G1 (38%), and G9 (11%) accounting for most of typeable strains. By our burden estimates, the Omani government spends an estimated US$791,817 and US$1.8 million annually to treat rotavirus-associated diarrhea in the outpatient and hospital settings, respectively. A rotavirus vaccination program might substantially reduce the burden of severe diarrhea among children in Oman.


Subject(s)
Cost of Illness , Rotavirus Infections/epidemiology , Rotavirus Vaccines/immunology , Child, Preschool , Diarrhea/epidemiology , Female , Humans , Infant , Infant, Newborn , Male , Oman/epidemiology , Rotavirus/classification , Rotavirus/genetics , Rotavirus Infections/economics , Rotavirus Infections/prevention & control , Rotavirus Infections/virology
9.
Indian J Pharmacol ; 41(3): 140-3, 2009 Jun.
Article in English | MEDLINE | ID: mdl-20442823

ABSTRACT

OBJECTIVE: To study the mechanism involved in hydrogen peroxide (H(2)O(2)) or tert-butyl hydroperoxide (t-BHP)-induced potentiation of the Ang II-mediated contraction of isolated rat thoracic aorta. MATERIALS AND METHODS: Thoracic aorta was isolated from the Sprauge dawley rats (300-320 gm), cut spirally and response to Ang II (5 x 10(-8)M) was taken in the absence and presence of H(2)O(2) (10(-6)M) and t-BHP (10(-5)M). To explore the probable mechanism of H(2)O(2) and t-BHP-induced potentiation of Ang II-mediated contractile response, different blockers such as losartan (AT(1) receptor blocker; 1 muM), catalase (H(2)O(2) scavenger; 500 U/ml), lercanidipine (L-type calcium channel blocker; 1 muM), geinistein (tyrosine kinase inhibitor; 100 muM), and indomethacin (cyclo-oxygenase inhibitor; 10 muM) were used. RESULTS: In spiral preparation of rat thoracic aorta, H(2)O(2) (10(-6)M) and t-BHP (10(-5)M) did not produce the contraction as such. However, when they are added simultaneously with Ang II (5 x 10(-8) M), they potentiated the contractile response of the Ang II. Catalase (500 U/ml) partially antagonized the Ang-II-induced contraction, as well as antagonized the potentiation induced by H(2)O(2). Losartan (1 muM) and lercanidipine (1 muM) antagonized the Ang II-induced contractile response without affecting H(2)O(2) (10(-6)M)-mediated potentiation. Geinistein (100 muM) antagonized H(2)O(2) (10(-6)M)-mediated potentiation, but it slightly decreased the Ang II response. Losartan (1 muM) and lercanidipine (1 muM) and Geinistein (100 muM) antagonized the Ang II-induced contractile response but not t-BHP-mediated potentiation. Indomethacin antagonized t-BHP-mediated potentiation without affecting much of Ang II response. CONCLUSION: From the above-mentioned results, we can reasonably conclude that H(2)O(2) and t-BHP potentiated the contraction induced by the Ang II. H(2)O(2)-induced potentiation of Ang II response may be mediated through tyrosine kinase activation and t-BHP through the activation of cyclo-oxygenase enzyme.

10.
Indian J Pharm Sci ; 70(1): 71-6, 2008 Jan.
Article in English | MEDLINE | ID: mdl-20390084

ABSTRACT

The purpose of this investigation was to develop fast dissolving tablets of etoricoxib. Granules containing etoricoxib, menthol, crospovidone, aspartame and mannitol were prepared by wet granulation technique. Menthol was sublimed from the granules by exposing the granules to vacuum. The porous granules were then compressed in to tablets. Alternatively, tablets were first prepared and later exposed to vacuum. The tablets were evaluated for percentage friability and disintegration time. A 3(2) full factorial design was applied to investigate the combined effect of 2 formulation variables: amount of menthol and crospovidone. The results of multiple regression analysis indicated that for obtaining fast dissolving tablets; optimum amount of menthol and higher percentage of crospovidone should be used. A surface response plots are also presented to graphically represent the effect of the independent variables on the percentage friability and disintegration time. The validity of a generated mathematical model was tested by preparing a checkpoint batch. Sublimation of menthol from tablets resulted in rapid disintegration as compared with the tablets prepared from granules that were exposed to vacuum. The optimized tablet formulation was compared with conventional marketed tablets for percentage drug dissolved in 30 min (Q(30)) and dissolution efficiency after 30 min (DE(30)). From the results, it was concluded that fast dissolving tablets with improved etoricoxib dissolution could be prepared by sublimation of tablets containing suitable subliming agent.

11.
Pharm Dev Technol ; 12(1): 21-33, 2007.
Article in English | MEDLINE | ID: mdl-17484141

ABSTRACT

Solid dispersions in water-soluble carriers have attracted considerable interest as a means of improving the dissolution rate, and hence possibly bioavailability, of a range of hydrophobic drugs. The aim of the present study was to improve the solubility and dissolution rate of a poorly water-soluble drug, Lovastatin, by a solid dispersion technique. Solid dispersions were prepared by using polyethylene glycol 4000 (PEG 4000) and polyvinylpyrrolidone K30 (PVP K30) in different drug-to-carrier ratios. Dispersions with PEG 4000 were prepared by fusion-cooling and solvent evaporation, whereas dispersions containing PVP K30 were prepared by solvent evaporation technique. These new formulations were characterized in the liquid state by phase solubility studies and in the solid state by differential scanning calorimetry, X-ray powder diffraction, and FT-IR spectroscopy. The aqueous solubility of Lovastatin was favored by the presence of both polymers. The negative values of the Gibbs free energy and enthalpy of transfer explained the spontaneous transfer from pure water to the aqueous polymer environment. Solid-state characterization indicated Lovastatin was present as amorphous material and entrapped in polymer matrix. In contrast to the very slow dissolution rate of pure Lovastatin, the dispersion of the drug in the polymers considerably enhanced the dissolution rate. This can be attributed to improved wettability and dispersibility, as well as decrease of the crystalline and increase of the amorphous fraction of the drug. Solid dispersion prepared with PVP showed the highest improvement in wettability and dissolution rate of Lovastatin. Even physical mixture of Lovastatin prepared with both polymers also showed better dissolution profile than that of pure Lovastatin. Tablets containing solid dispersion prepared with PEG and PVP showed significant improvement in the release profile Lovastatin compared with tablets containing Lovastatin without PEG or PVP.


Subject(s)
Hydroxymethylglutaryl-CoA Reductase Inhibitors/administration & dosage , Hydroxymethylglutaryl-CoA Reductase Inhibitors/chemistry , Lovastatin/administration & dosage , Lovastatin/chemistry , Calorimetry, Differential Scanning , Chemical Phenomena , Chemistry, Pharmaceutical , Chemistry, Physical , Crystallography, X-Ray , Excipients , Polyethylene Glycols , Povidone , Solubility , Spectrophotometry, Infrared , Spectroscopy, Fourier Transform Infrared , Thermodynamics
12.
J Oral Rehabil ; 34(5): 361-76, 2007 May.
Article in English | MEDLINE | ID: mdl-17441877

ABSTRACT

This prospective split-mouth clinical trial evaluated the performance and patient satisfaction of 168 Herculite XRV direct composite restorations bonded to the worn anterior dentition of 18 patients with localized anterior tooth surface loss. One hundred and six of these restorations were placed on the mandibular anterior teeth. The restorations increased the anterior occlusal vertical dimension between 0.5 and 5 mm and the posterior occlusal contacts were restored after a mean duration of 6.2 months (range: 3-13 months) in 14 out of the 15 'Dahl' sub-group patients. The restorations were evaluated after 2.5 years of service by five examiners. Four patients and 23 mandibular restorations were lost to follow-up. Multiple clinical and restorative variables were assessed to determine their influence on restoration performance. Complete failure occurred in 6% of the restorations. Circumferential preparation and height of the restorative addition did not influence the performance of the restorations. A Visual Analogue Scale (VAS) was used to assess the patient's opinion regarding sensitivity, aesthetics, longevity and function of the worn mandibular anterior teeth. A statistically significant difference (95% CI) was found between the pre-operative and 1-month review VAS responses for aesthetics and longevity and this was maintained at the 2.5-year review. Direct composite restorations placed at an increased occlusal vertical dimension are a simple and time-efficient method of managing the worn mandibular anterior dentition. Patient's acceptance and adaptation to the technique is good and the results are accompanied with a high level of patient satisfaction that is maintained for the medium-term.


Subject(s)
Dental Restoration, Permanent/methods , Resin Cements/therapeutic use , Tooth Diseases/surgery , Adult , Aged , Composite Resins , Dental Enamel , Dental Occlusion , Dental Restoration Failure , Dentin-Bonding Agents/therapeutic use , Esthetics, Dental , Female , Humans , Male , Mandible , Middle Aged , Patient Satisfaction , Prospective Studies , Surveys and Questionnaires , Treatment Outcome , Vertical Dimension
13.
Curr Drug Deliv ; 3(3): 325-31, 2006 Jul.
Article in English | MEDLINE | ID: mdl-16848734

ABSTRACT

Buccal adhesive patches containing 20 mg of propranolol hydrochloride were prepared using solvent casting method. Chitosan was used as a natural bioadhesive polymer. Patches were prepared at different ratios of PVP K-30 and evaluated for various physicochemical characteristics such as weight variation, drug content uniformity, folding endurance, surface pH, ex-vivo mucoadhesive strength, ex-vivo residence time, in vitro drug release and in vitro buccal permeation study. Patches exhibited sustained release over a period of 7 hours. The mechanism of drug release was found to be Non-Fickian diffusion. Addition of PVP K-30 generally enhanced the releasing rate. The ex-vivo mucoadhesive strength was performed using sheep buccal mucosa on modified physical balance. Optimized patches (batch F4) showed satisfactory bioadhesive strength (9.6 degrees 2.0 gram) and ex vivo residence time (272 degrees 0.25 minutes). Swelling index was proportional to PVP K-30. The surface pH of all batches was within satisfactory limit (7.0+/-1.5) and hence patches would not cause irritation in the buccal cavity. Good correlation was observed between in vitro drug release and in vitro drug permeation with correlation coefficient of 0.9364. Stability of optimized patches was performed in natural human saliva showed that both drug and dosage forms were stable in human saliva.


Subject(s)
Delayed-Action Preparations/chemistry , Drug Delivery Systems/methods , Propranolol/administration & dosage , Adhesiveness , Administration, Buccal , Animals , Biological Availability , Chitosan/chemistry , Drug Stability , Humans , Hydrogen-Ion Concentration , Mouth Mucosa/metabolism , Povidone/chemistry , Propranolol/chemistry , Propranolol/pharmacokinetics , Propylene Glycol/chemistry , Saliva/metabolism , Sheep , Surface Properties , Water/chemistry
15.
Endocrinology ; 145(9): 4078-83, 2004 Sep.
Article in English | MEDLINE | ID: mdl-15231713

ABSTRACT

Phosphoinositide 3-kinase (PI3 kinase) has been implicated in G protein-coupled receptor regulation of pancreatic beta-cell growth and glucose-stimulated insulin secretion. The G protein-activated p110gamma isoform of PI3 kinase was detected in insulinoma cells, mouse islets, and human islets. In 7- to 10-wk-old mice, knockout of p110gamma reduced the plasma insulin response to ip glucose injection and impaired first and second phase glucose-stimulated insulin secretion from pancreata perfused ex vivo. The p110gamma -/- mice responded to preinjection with the glucagon-like peptide-1 receptor agonist exendin 4, such that plasma glucose and insulin responses to ip glucose injection were not different from wild types. Mice lacking p110gamma were not diabetic and were only slightly glucose intolerant (ip glucose injection) compared with wild types, in part due to enhanced responsiveness to insulin as determined by an ip insulin tolerance test. Despite severely reduced insulin secretion in these animals, the p110gamma -/- mice had greater pancreatic insulin content, and an increased beta-cell mass due to beta-cell hypertrophy. These surprising results suggest that the G protein-coupled p110gamma isoform of PI3 kinase is not central to the development or maintenance of sufficient beta-cell mass but positively regulates glucose-stimulated insulin secretion.


Subject(s)
Insulin/metabolism , Islets of Langerhans/enzymology , Isoenzymes/genetics , Phosphatidylinositol 3-Kinases/genetics , Animals , Class Ib Phosphatidylinositol 3-Kinase , Exenatide , Glucose/pharmacology , Homeostasis/physiology , Injections, Intraperitoneal , Insulin Secretion , Islets of Langerhans/metabolism , Isoenzymes/metabolism , Male , Mice , Mice, Inbred C57BL , Mice, Knockout , Peptides/pharmacology , Phosphatidylinositol 3-Kinases/metabolism , Venoms/pharmacology
16.
Indian J Cancer ; 41(1): 25-31, 2004.
Article in English | MEDLINE | ID: mdl-15105576

ABSTRACT

BACKGROUND: The changes in lipid profile have long been associated with cancer because lipids play a key role in maintenance of cell integrity. AIMS: The present study evaluated alterations in plasma lipid profile in untreated head and neck cancer patients as well as patients with oral precancerous conditions (OPC) and its association with habit of tobacco consumption. MATERIAL AND METHODS: This hospital-based case control study included 184 head and neck cancer patients, 153 patients with OPC and 52 controls. Plasma lipids including: (i) Total cholesterol, (ii) LDL cholesterol (LDLC), (iii) HDL cholesterol (HDLC) (iv) VLDL cholesterol (VLDLC) and (v) triglycerides were analysed by spectrophotometric kits. STATISTICAL ANALYSIS USED: Student's t-test was performed to compare mean values of the parameters. RESULTS: A significant decrease in plasma total cholesterol and HDLC was observed in cancer patients (P=0.008 and P=0.000 respectively) as well as in patients with OPC (P=0.014 and P=0.000, respectively) as compared to the controls. The plasma VLDL and triglycerides levels were significantly lower in cancer patients as compared to the patients with OPC (P=0.04) and controls (P=0.059). The tobacco habituates showed lower plasma lipid levels than the non-habituates. Our data strengthen the evidence of an inverse relationship between plasma lipid levels and head and neck malignancies as well as OPC. CONCLUSION: The lower levels of plasma cholesterol and other lipid constituents in patients might be due to their increased utilization by neoplastic cells for new membrane biogenesis. The findings strongly warrant an in-depth study of alterations in plasma lipid profile in head neck cancer patients.


Subject(s)
Cholesterol/blood , Head and Neck Neoplasms/blood , Mouth Neoplasms/blood , Precancerous Conditions/blood , Triglycerides/blood , Adult , Aged , Carcinoma, Squamous Cell/blood , Case-Control Studies , Cholesterol, HDL/blood , Cholesterol, LDL/blood , Cholesterol, VLDL/blood , Female , Humans , Leukoplakia, Oral/blood , Male , Middle Aged , Oral Submucous Fibrosis/blood , Smoking/blood , Spectrophotometry , Tobacco, Smokeless
17.
Drug Dev Ind Pharm ; 29(5): 565-74, 2003 May.
Article in English | MEDLINE | ID: mdl-12779286

ABSTRACT

This article reports the preparation of tartaric acid treated ispaghula husk powder for the development of modified release tablets of diltiazem HCl by adopting direct compression technique and a 32 full factorial design. The modified ispaghula husk powder showed superior swelling and gelling as compared to untreated powder. Addition of compaction augmenting agent such as dicalcium phosphate was found to be essential for obtaining tablets with adequate crushing strength. In order to improve the crushing strength of diltiazem HCl tablets, to modulate drug release pattern, and to obtain similarity of dissolution profiles in distilled water and simulated gastric fluid (pH 1.2), modified guar gum was used along with modified ispaghula husk powder and tartaric acid. A novel composite index, which considers a positive or a negative deviation from an ideal value, was calculated considering percentage drug release in 60, 300, and 540 min as dependent variables for the selection of a most appropriate batch. Polynomial equation and contour plots are presented. The concept of similarity factor (f2) was used to prove similarity of dissolution in water and simulated gastric fluid (pH 1.2).


Subject(s)
Diltiazem/chemistry , Compressive Strength , Delayed-Action Preparations/chemistry , Drug Carriers/chemistry , Drug Compounding , Galactans/chemistry , Gels , Kinetics , Mannans/chemistry , Models, Chemical , Plant Gums , Powders , Psyllium/chemistry , Solubility , Tablets , Tartrates/chemistry , Time Factors
18.
J Virol Methods ; 108(2): 189-93, 2003 Mar.
Article in English | MEDLINE | ID: mdl-12609686

ABSTRACT

The recent discovery of human herpesvirus 8 (HHV-8) as the etiologic agent of Kaposi's sarcoma (KS) has led to the interest in the development of PCR for this virus that is accurate, rapid, and convenient. We developed a sensitive PCR assay for HHV-8 with microtiter plate detection of amplimers. DNA was purified from white blood cells and saliva from HIV-infected men with and without Kaposi's sarcoma and one-step PCR was undertaken with primer sets specific for the N-terminal region of the glycoprotein B gene and open reading frame (orf) 26 of HHV-8. PCR was performed on 40 clinical specimens, followed by Southern blot and microtiter plate detection of amplimers. Results from the two methods of detection were nearly identical. Sensitivity for both methods based on serial dilution of a known standard was five to ten copies of HHV-8 per 400 ng of cellular DNA. In conclusion, microtiter plate detection of HHV-8 PCR amplimers is as sensitive and specific as Southern blot with much faster turnaround time at comparable cost, and utilizes common laboratory equipment.


Subject(s)
Blotting, Southern/methods , DNA, Viral/genetics , DNA, Viral/isolation & purification , Herpesvirus 8, Human/genetics , Herpesvirus 8, Human/isolation & purification , Virology/methods , Base Sequence , Blotting, Southern/statistics & numerical data , DNA Probes/genetics , DNA, Viral/blood , Enzyme-Linked Immunosorbent Assay/methods , Enzyme-Linked Immunosorbent Assay/statistics & numerical data , HIV Infections/complications , HIV Infections/virology , Humans , Male , Polymerase Chain Reaction/methods , Polymerase Chain Reaction/statistics & numerical data , Reproducibility of Results , Saliva/virology , Sarcoma, Kaposi/complications , Sarcoma, Kaposi/virology , Sensitivity and Specificity , Virology/statistics & numerical data
19.
Neoplasma ; 49(4): 260-6, 2002.
Article in English | MEDLINE | ID: mdl-12382026

ABSTRACT

Glutathione, an antioxidant plays an important role in phase-II detoxification of carcinogens. The levels of reduced glutathione are maintained by glutathione-depleting as well as replenishing enzymes such as glutathione-s-transferase (GST) and glutathione reductase (GR), respectively. Pre and post treatment changes in GST and GR activities in head and neck cancer patients were analysed. Serum GST and GR were analysed from untreated head and neck cancer patients (PT) (n=146), controls with habit of tobacco (VHT) (n=25) as well as without (no) habit of tobacco (NHT) (n=25) and patients with oral precancerous conditions (OPC) (n=50). The cancer patients were followed-up after initiation of anticancer therapy. Follow-up blood samples were collected. Serum GST and GR activities were estimated by highly sensitive and specific spectrophotometric methods. Untreated cancer patients showed elevated mean serum GST and GR activities as compared to NHT. Patients with OPC had declined mean GST activity as compared to WHT and untreated cancer patients. Paired t-test revealed that complete responders (CR) showed significantly elevated GST levels and declined GR activities (p < 0.001) as compared to those in PT. No correlation was found between stage of the disease and GST, GR activity. Paired t-test showed significant decreased in GR activity in nonresponders (NR) treated with radiotherapy (p=0.01). The study suggested that analysis of glutathione and glutathione-depleting enzymes can be helpful for treatment monitoring of head and neck cancer patients.


Subject(s)
Glutathione Reductase/metabolism , Glutathione Transferase/blood , Head and Neck Neoplasms/enzymology , Adult , Aged , Carcinoma, Squamous Cell/diagnosis , Carcinoma, Squamous Cell/enzymology , Carcinoma, Squamous Cell/therapy , Head and Neck Neoplasms/diagnosis , Head and Neck Neoplasms/therapy , Humans , Male , Middle Aged , Neoplasm Staging , Precancerous Conditions/blood , Precancerous Conditions/enzymology , Smoking
20.
J Clin Microbiol ; 39(10): 3537-40, 2001 Oct.
Article in English | MEDLINE | ID: mdl-11574569

ABSTRACT

A quantitative, fluorescence-based PCR assay (TaqMan-based system) was developed for detection of human herpesvirus 8 (HHV-8) DNA in clinical specimens. Primers and probes chosen from each of five 10-kb segments from the unique region of the HHV-8 genome were evaluated for sensitivity with dilution series of DNA extracted from a cell line (BCBL-1) that harbors HHV-8 DNA. Although several of the primer-probe sets performed similarly with BCBL-1 DNA that had been diluted in water, their performance differed when target DNA was diluted in a constant background of uninfected cell DNA, an environment more relevant to their intended use. The two best primer-probe combinations were specific for HHV-8 relative to the other known human herpesviruses and herpesvirus saimiri, a closely related gammaherpesvirus of nonhuman primates. PCRs included an enzymatic digestion step to eliminate PCR carryover and an exogenous internal positive control that enabled discrimination of false-negative from true-negative reactions. The new assays were compared to conventional PCR assays for clinical specimens (saliva, rectal brushings, rectal swab specimens, peripheral blood lymphocytes, semen, and urine) from human immunodeficiency virus-positive patients with or without Kaposi's sarcoma. In all instances, the new assays agreed with each other and with the conventional PCR system. In addition, the quantitative results obtained with the new assays were in good agreement both for duplicate reactions in the same assay and between assays.


Subject(s)
DNA, Viral/analysis , Herpesvirus 8, Human/isolation & purification , Polymerase Chain Reaction/methods , Sarcoma, Kaposi/virology , AIDS-Related Opportunistic Infections/virology , DNA Probes , Fluorescent Dyes , Herpesvirus 8, Human/genetics , Humans , Sensitivity and Specificity , Taq Polymerase/metabolism
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