Ether phospholipids in control and 20∶4-depleted rat PMN: Additional evidence for a 1-0-alkyl-2-20∶4-sn-glycerol-3-phosphocholine specific phospholipase A2

Earlier studies from our laboratory have shown that PAF and LTB₄ biosynthesis are inhibited in rat PMN depleted of its 203 (JBC. '86,261, 7592). To test whether these cells contain sufficient 1-O-alkyl-2-acyl-GPC to support PAF synthesis, phosphotidyl choline was isolated from these 204-depleted cells, fractionated into different subclasses and their fatty acid composition determined. These results were compared with those obtained with control PMN. Both control and 204-depleted PMN contained significantly large amounts of alkylacyl-GPC and diacyl-GPC. Small amounts (4%) of alkenylacyl-GPC were also present. The amount of 203 in 204-depleted cells was more or less equal to the amount of 204 in control cells. About 62% of PC-bond 204 in control PMN and about 56% of PC-bound 203 in the 204-depleted PMN was found associated with the alkylacyl species. These results show that both control and 204 depleted PMN have ample precursor substrates to support PAF biosynthesis and these substrates are enriched with 204 in control cells and with 203 in 204-depleted cells. These findings are consistant with the existance of a highly specific phospholipase A₂ capable of distinguising 204 from 203 containing phospholipids.     

Energy Consumption and Sensitivity Analysis of Rainfed Chickpea Production in Vertisols of Semi-arid Karnataka

Proceedings of the National Academy of Sciences, India Section B: Biological Sciences - In-situ rainwater conservation improves chickpea productivity in Vertisols. This hypothesis was tested by...     

Nitrate-Melt Synthesized HT-LiCoO2 as a Superior Cathode-Material for Lithium-Ion Batteries

An electrochemically-active high-temperature form of LiCoO₂ (HT-LiCoO₂) is prepared by thermally decomposing its constituent metal-nitrates at 700 ºC. The synthetic conditions have been optimized to achieve improved performance with the HT-LiCoO₂ cathode in Li-ion batteries. For this purpose, the synthesized materials have been characterized by powder X-ray diffraction, scanning electron microscopy, and galvanostatic charge-discharge cycling. Cathodes comprising HT-LiCoO₂ exhibit a specific capacity of 140 mAhg^-1 with good capacity-retention over several charge-discharge cycles in the voltage range between 3.5 V and 4.2 V, and can sustain improved rate capability in contrast to a cathode constituting LiCoO₂ prepared by conventional ceramic method. The nitrate-melt-decomposition method is also found effective for synthesizing Mg-/Al- doped HT-LiCoO₂; these also are investigated as cathode materials for Li-ion batteries.     

Fungal infections of the central nervous system in HIV-negative patients: Experience from a tertiary referral center of South India

Objective:

To describe the clinical, radiological, and cerebrovascular fluid (CSF) findings and the outcome of microbiologically or histopathologically proven fungal infections of the central nervous system (CNS) in HIV-negative patients.

Methodology and Results:

We identified definite cases of CNS mycosis by screening the medical records of our institute for the period 2000–2008. The clinical and imaging details and the outcome were abstracted from the medical records and entered in a structured proforma. There were 12 patients with CNS mycosis (i.e., 2.7% of all CNS infections treated in this hospital); six (50%) had cryptococcal infection, three (25%) had mucormycosis, and two had unclassified fungal infection. Four (33%) of them had diabetes as a predisposing factor. The common presentations were meningoencephalitis (58%) and polycranial neuritis (41%). Magnetic resonance imaging revealed hydrocephalus in 41% and meningeal enhancement in 25%, as well as some unusual findings such as subdural hematoma in the bulbocervical region, carpeting lesion of the base of the skull, and enhancing lesion in the cerebellopontine angle. The CSF showed pleocytosis (66%), hypoglycorrhachia (83%), and elevated protein levels (100%). The diagnosis was confirmed by meningocortical biopsy (in three cases), paranasal sinus biopsy (in four cases), CSF culture (in three cases), India ink preparation (in four cases), or by cryptococcal polysaccharide antigen test (in three cases). Out of the ten patients for whom follow-up details were available, six patients recovered with antifungal medications (amphotericin B, 1 mg/kg/day for the minimum period of 6 weeks) and/or surgical treatment. Four patients expired (only one of them had received antifungal therapy).

Conclusions:

Most patients with CNS mycosis recover with appropriate therapy, but the diagnosis and management of these rare infections remains a challenge to clinicians.     

Determinants of gestational diabetes mellitus: A case control study in a district tertiary care hospital in south India

Objective:

To study the determinants of Gestational Diabetes Mellitus (GDM).

Design:

Case-control study. Setting: Sri Avittom Thirunal Hospital, Thiruvananthapuram district, Kerala, South India.

Participants:

300 GDM women as cases and 300 age-matched controls.

Study variables:

Sociodemographic characteristics, pre-pregnancy Body Mass Index (BMI), menstrual history, obstetric history, infertility history, family history of diabetes in first degree relatives, recurrent urinary tract infection (UTI), and moniliasis.

Statistical analysis:

T-test, Fishers Exact Test, Chi square test, Adjusted Odds Ratio with 95% CI. Results: Pre-pregnancy BMI ≥ 25 (P < 0.001, OR = 2.7), irregular menstrual cycle (P = 0.006), treatment for infertility (P = 0.001, OR = 3.3), family history of diabetes (P = 0.001, OR = 4.5), history of diabetes in mother (P = 0.003), previous pregnancy losses (P = 0.04), past GDM (P = 0.035), prematurity (P = 0.01), pre-eclampsia (P = 0.04), polyhydramnios (P < 0.001, OR = 6.0), UTI (P < 0.001, OR = 3.2), and moniliasis (P < 0.001, OR = 7.6) were significantly associated with present GDM.

Conclusion:

Early identification of women at risk of GDM and prompt treatment is recommended to prevent complications.     

Effects of carcinogen and/or mutagen on normal and gonadotropin-primed ovaries of mice

The influence of pregnant mare serum gonadotropin (PMSG) on the induction of ovarian tumors by carcinogen (DMBA) and/or mutagens (EMS and BMS) has been studied in Swiss albino mice. Priming of the ovaries of 6-week-old mice with PMSG (50 lU/mouse) 24 h before intragastric intubation of DMBA (5 mg/mouse) resulted in a significant increase in ovarian tumors when harvested 6 months after the treatment. A similar experiment done on 8-week-old mice yielded confirmatory results. Mutagens (EMS and BMS) failed, at given dose levels (200 mg/kg and 300 mg/kg body weight), to induce tumors in normal as well as PMSG-primed ovaries. Nor could these mutagens enhance DMBA-induced tumor incidences in normal or PMSG-primed ovaries. Pretreatment of animals with PMSG-enhanced DMBA-induced oocyte depletion and also increased the DMBA-³H activity in the ovaries. The augmentation of DMBA-induced tumors in PMSG-primed ovaries could be due to increased uptake of DMBA and increased depletion of oocytes. It is also possible that PMSG-primed ovaries provided more proliferating granulosa cells (and macromolecules) for the interaction of DMBA (or its metabolites) and thereby increased the chances of cell transformation in the ovaries.     

Protein extract of kenaf seed exhibits anticoagulant,antiplatelet and antioxidant activities

Objective:To explore the anticoagulant,antiplatelet and antioxidant activities of protein extract of kenaf seed(PEKS).Methods:Sodium dodecyl sulphate polyacrylamide gel electrophoresis and reverse-phase high-performance liquid chromatography techniques were employed for protein characterization.Antioxidant activity of PEKS was assessed using 1,1-diphenyl-2-picrylhydrazyl(DPPH)assay.The protective effect of PEKS on sodium nitrite(NaNO2)induced oxidative stress was evaluated using the in vitro red blood cell model,while the effect of PEKS on diclofenacinduced oxidative stress was examined in vivo in rats.Platelet-rich plasma and platelet-poor plasma were used for anticoagulant and antiplatelet activities of PEKS.Results:PEKS revealed similar protein bands on SDS-PAGE under reduced and non-reduced conditions.Several acidic proteins were present in native PAGE.PEKS showed antioxidant properties by scavenging DPPH with an IC50 of 24.58μg.PEKS exhibited a protective effect on NaNO2 induced oxidative stress in red blood cells by restoring the activity of stress markers.In addition,PEKS alleviated diclofenac-induced tissue damage of the liver,kidney,and small intestine.PEKS showed an anticoagulant effect in both in vivo and in vitro experiments by enhancing normal clotting time.PEKS did not affect prothrombin time but increase activated partial thromboplastin time.Furthermore,PEKS inhibited adenosine diphosphate and epinephrine-induced platelet aggregation.Conclusions:PEKS protects tissues from oxidative stress and exhibits antithrombotic activity.