Pressure induced critical behavior of ferromagnetic phase transition in Sm-Nd-Sr manganites

We report on the hydrostatic pressure dependence of the order of ferromagnetic (FM) to paramagnetic (PM) phase transition in a (Sm(0.7)Nd(0.3))(0.52)Sr(0.48)MnO(3) single crystal. At ambient pressure, the system undergoes a first-order FM-PM phase transition at 146 K. The application of pressure increases the T(C), suppresses the hysteresis width, and thus makes the transition second order. We have analyzed the critical behavior associated with the second-order FM-PM transition in the presence of an external pressure (12.1 kbar) and obtained the critical exponents beta=0.358, gamma=1.297, and delta=4.536, which are close to those predicted for the three-dimensional Heisenberg system. Using these values of beta, gamma, and T(C) ( approximately 176 K), one can scale the magnetization data below and above T(C) following a single equation of state.

Bax and Bid act in synergy to bring about T11TS-mediated glioma apoptosis via the release of mitochondrial cytochrome c and subsequent caspase activation

The specific apoptotic role of T11TS has been well established in glioma animal models. T11TS specifically induces the glioma cells to die an apoptotic death via immune cross-talk with the two intracranial immune competent cells-microglia and the brain-infiltrating lymphocytes. To unearth the molecular cascades operative within the glioma cells and to some extent in the two interacting immunocytes, we had initiated studies where preliminary findings not only had indicated the involvement of death receptors but had also hinted to the involvement of other apoptotic regulators. Hence, to identify the molecular pathway of apoptosis involving other apoptotic regulators in the three cell types, the cells were studied for the intrinsic apoptotic death regulators that were engaged to maintain the mitochondrial membrane integrity. The proteins that were selected could be divided into three broad classes-the Bcl-2 family of proteins-Bid, Bax and Bcl-2; the guardian of the genome p53 and the proteins downstream of mitochondria-Apaf-1, cytochrome c, caspase-9 and caspase-3. Activated Bid as well as maximal p53 expression was observed in the first dose of T11TS thus dually activating the pro-apoptotic Bax in the first and second dose in the glioma cells. Concurrently, the pro-survival protein Bcl-2's expression level was very much down-regulated in the same two doses favoring the internal microenvironment to proceed for apoptosis. High expression of cytochrome c and Apaf-1 and the presence of active caspase-9 and active caspase-3 in all the T11TS-treated tumor-bearing groups further adjudicated apoptosis of the glioma cells with clear involvement of mitochondrial death pathway in the T11TS-treated animals. Even though expression of the apoptotic regulators remained more or less the same indicating the involvement of mitochondria in the two interacting immunocytes, the intensity of expression of these proteins was much lower than the tumor cells. The present work focuses on the mechanistic approach of how T11TS mediates apoptosis and hence is the first approach of its kind in the field of immunology where the immunotherapeutic molecule's mode of action has been worked out.

Quality of child-parent attachment moderates the impact of antenatal stress on child fearfulness

BACKGROUND

Animal studies have shown that prenatal stress has persisting effects on several aspects of offspring development; more recent studies show that this effect may be eliminated by positive postnatal rearing. Human studies of prenatal anxiety/stress are now also beginning to document links between antenatal stress/anxiety and behavioural and cognitive development of the child; however, there is no human evidence as to whether the early caregiving environment moderates the effect of antenatal anxiety/stress on child outcomes.

METHODS

Antenatal and postnatal measures of stress were collected on 123 women who were recruited from an antenatal clinic. Laboratory-based assessment of the children's cognitive development and fearfulness were assessed when the children were aged 17 months. In addition, child-parent attachment quality was assessed using the Strange Situation.

RESULTS

Attachment classification moderated the link between antenatal stress and observed fearfulness. The effect of antenatal stress on fearfulness was most accentuated in children with an Insecure/Resistant attachment classification; the significant antenatal stress x attachment classification interaction held after controlling for postnatal stress and obstetric, social and demographic factors. Attachment did not moderate the effects of antenatal anxiety on cognitive development.

DISCUSSION

These findings provide the first human evidence that postnatal parenting may moderate the adverse effects of antenatal stress. These results raise developmental questions about the timing and effect of interventions to reduce the adverse effects of antenatal stress exposure.

Metal Enhanced Fluorescence on Silicon Wafer Substrates

We report on the fluorescence enhancement induced by silver island film (SIF) deposited on a silicon wafer. The model immunoassay was studied on silvered and unsilvered wafers. The fluorescence brightness of Rhodamine Red X increased about 300% on the SIF, while the lifetime was reduced by several fold and the photostability increased substantially. We discuss potential uses of silicon wafer substrates in multiplex assays in which the fluorescence is enhanced due to the SIF, and the multiplexing is achieved by using micro transponders.

Rheumatological manifestations in diabetes mellitus

A study was undertaken in the department of medicine from November 2003 to July 2005 with a view to find out the prevalence of different rheumatological problem in Indian diabetic population. Although several such studies have been conducted in western population very limited data are available from our country. A total of 80 patients were studied out of which 43 had some form of rheumatological manifestations. Dupuytren's contracture was found in highest number of cases (n = 23) followed by limited joint mobility in 16 patients; adhesive capsulitis in 19 patients; trigger finger in 4 patients; aglodystrophy, carpal tunnel syndrome and hyperostosis were found in 2, 3 and 2 cases respectively. Symptomatic osteo-arthritis was found in 19 cases.

Outcome of Alcohol Dependence Syndrome Cases Managed in Armed Forces

BACKGROUND

Army Order for Alcohol Dependence Syndrome gives a structured and strict approach towards disposal of such cases in Indian Armed Forces. Four years have passed since the implementation of the above order. This study was conducted to assess the outcome after implementation of the said order.

METHODS

231 male soldiers reporting for review after six months and one year of initial treatment were included in the study. Data was obtained from history, physical examination, mental state, laboratory and other investigations. The data was analyzed and compared with previous study.

RESULT

231 patients were reviewed in this period of four years, of which 149 patients were reviewed after six months and 77 after one year. Five patients were reviewed beyond one year. 50 - 53% patients have shown complete improvement after the initial treatment and 23.5 - 31% have shown partial improvement after the initial treatment. The rest did not show much improvement. The results are better than the previous results from study conducted before implementation of the new Army Order.

CONCLUSION

The study strengthens the validity of the present Army Order, which is structured and may be having a deterrent value, leading to better prognosis.

Maternal antenatal anxiety and amniotic fluid cortisol and testosterone: possible implications for foetal programming

Both animal and human studies have shown that maternal stress or anxiety during pregnancy is associated with increased risk of disturbance in offspring neurodevelopment and behaviour. In animal models, increased foetal exposure to glucocorticoids has been found to be one mechanism for such foetal programming. Little is understood of the mediating mechanisms in humans, and one aim of our research programme is to investigate this further. This review presents a synopsis of some of our recent results. We aimed to test the hypothesis that maternal anxiety was associated with raised maternal cortisol, and that this in turn was related to increased foetal exposure to cortisol. We studied this by recruiting women at amniocentesis, obtained their Spielberger State Anxiety scores, and assessed maternal plasma cortisol and amniotic fluid cortisol. We also examined maternal plasma and amniotic fluid testosterone levels. Awaiting amniocentesis was in general anxiogenic, but with a wide range of anxiety scores. Maternal anxiety was significantly associated with plasma cortisol before 17 weeks, albeit of modest magnitude (r = 0.0.23), and not after 17 weeks of gestation. This is probably due to the known attenuation of the maternal hypothalamic-pituitary-adrenal axis with increasing gestation. We found a strong correlation between maternal plasma and amniotic fluid cortisol levels, which increased with gestation and became robust after 18 weeks. This correlation increased with maternal anxiety, suggesting a possible effect of maternal mood on placental function. There was a positive correlation between cortisol and testosterone in amniotic fluid, in both male and female foetuses independent of maternal anxiety, plasma testosterone, gestational age, and time of collection. Foetal stress may be associated with increased foetal exposure to testosterone. However, maternal anxiety did not predict amniotic fluid cortisol or testosterone level. Thus, the role of these hormones in mediating the effect of maternal mood on foetal development in humans remains to be demonstrated.

Detection of pesticide by polymeric enzyme electrodes

Screen-printed electrodes (SPEs) containing immobilized acetylcholine esterase (AChE) enzyme were used for the electrochemical determination of organophosphorous (OP) and carbamate pesticides. The extent of AChE deactivation by the pesticide was determined in the presence of acetylcholine (AChCl) substrate. The unique nature of this approach lies in the enzyme immobilization procedure in which AChE was attached to the SPE by in situ bulk polymerization of acrylamide to ensure efficient adherence within the membrane with minimal losses in enzyme activity. Responses were observed for the pesticides Monocrotophos, Malathion, Metasystox and Lannate over the concentration range 0-10 ppb (microg L(-1)).

Postural orthostatic tachycardia syndrome

Postural orthostatic tachycardia syndrome (POTS) is an autonomic disturbance which has become better understood in recent years. It is now thought to encompass a group of disorders that have similar clinical features, such as orthostatic intolerance, but individual distinguishing parameters--for example, blood pressure and pulse rate. The clinical picture, diagnosis, and management of POTS are discussed.

Fish scales as bio-indicator of water quality of River Ganga

Various studies have been conducted in the past on the fresh waters related to the various aspects of limnology, physico-chemistry, primary productivity, plankton etc. in relation to environmental conditions and ecology, flora and fauna of River Ganga. In the present investigation some recent approach have been made to study the various parts of fishes like gill structures, scales for age determination, length and weight of fish for growth assessments etc. The SEM study of scales in relation to pollution and environmental conditions is a recent approach. At this stage, in the present study the scales of two most common fishes found in the study stretch were involved to create a base line.

Amniotic fluid testosterone: relationship with cortisol and gestational age

INTRODUCTION

Foetal exposure to testosterone is increasingly implicated in the programming of future reproductive and non-reproductive behaviour. Some outcomes associated with prenatal exposure to testosterone may be predicted from exposure to prenatal stress, suggesting a link between them. The peak serum levels of testosterone in the foetus are thought to be around 14-18 weeks' gestation, and we explored testosterone levels at different gestations. Although best investigated in foetal plasma, this is now difficult because of the decline in frequency of foetal blood sampling; in this study, we used amniotic fluid as a biomarker to investigate foetal exposure.

AIMS

To investigate the relationship between amniotic fluid testosterone, amniotic fluid cortisol, foetal gender, and gestational age.

METHODS

Paired amniotic fluid and maternal plasma samples were collected from 264 pregnant women undergoing amniocentesis between 15 and 37 weeks' gestation (median 17 weeks [119 days]). Total testosterone and cortisol in amniotic fluid, and total plasma testosterone (maternal) were measured by radioimmunoassay.

RESULTS

Amniotic fluid testosterone levels were higher in male than in female foetuses, with a median (interquartile range) of 0.85 nmol/l (0.60-1.17 nmol/l) and 0.28 nmol/l (0.175-0.45 nmol/l), respectively. No relationship between amniotic fluid testosterone and gestational age was detected in either sex. Amniotic fluid testosterone correlated positively with amniotic fluid cortisol in both sexes (r = 0.30 male foetuses, r = 0.33 female foetuses, P < 0.001 for both), and remained significant in multivariate analysis.

CONCLUSION

Testosterone in amniotic fluid did not change with gestation in the second and third trimester, raising questions about the timing of the reported early peak in the male foetus. The positive correlation between cortisol and testosterone in amniotic fluid suggests that increased foetal exposure to cortisol may also be associated with increased exposure to testosterone.

The other side of the coin: beneficiary effect of 'oxidative burst' upsurge with T11TS facilitates the elimination of glioma cells

Free radicals and allied molecules are the potential threats for the cellular components when they are produced in excess amount and cause different pathophysiological disorders including aging. Contrary to their detrimental effects, these molecules, in the other hand, can be utilized by the Phagocytic cells to destroy the abnormal cells and cellular components. Generation of reactive oxygen species (ROS) and nitric oxide (NO) are used as important effector molecules by Phagocytic macrophage/microglia to eliminate neoplastic cells in glioma bearing rat model. The glycoprotein T11TS/SLFA-3, by binding with CD2 receptor of macrophage/microglia, induces the generation of these reactive species when applied in three consecutive doses in glioma bearing animals. The CR3 family receptor CD11b is also correlated with the Phagocytic activity of the cells. The 'controlled' and directed production of ROS and NO by phagocytes induce cell death signals to the glioma cells and resulted in phagocytic destruction and apoptosis. The death signals generated by the free radicals and associated molecules resulted in accumulation of p53 proteins in the glioma cells. This oxidative stress induced p53 protein accumulation in neoplastic cells direct them to die by apoptosis. Therefore, the same oxidative stress causing pathophysiological problems, are used here to destroy the glioma cells by the macrophage/microglia in the delicate CNS tissue.

Ontogeny of foetal exposure to maternal cortisol using midtrimester amniotic fluid as a biomarker

OBJECTIVE

There is increasing evidence that antenatal stress has long-lasting effects on child development, but there is less accord on the mechanisms and the gestational window of susceptibility. One possible mechanism is by foetal exposure to maternal cortisol. To explore this, we investigated the relationship between cortisol in maternal plasma and amniotic fluid, and any moderating influence of gestational age.

PATIENTS AND MEASUREMENTS

Two hundred and sixty-seven women awaiting amniocentesis for karyotyping were studied. Samples were collected between 0900 and 1730 h. Gestational age was determined to the nearest day by ultrasound biometry and time of collection noted to the nearest 15 min. Total cortisol was measured by radioimmunoassay in paired amniotic fluid and maternal blood samples (n = 267) [gestation range 15-37 weeks, median 17 weeks (119 days)].

RESULTS

Both maternal and amniotic fluid cortisol levels increased with gestation (r = 0.25, P < 0.001; r = 0.33 P < 0.001, respectively). Amniotic fluid cortisol was positively correlated with time of collection (r = 0.22, P < 0.001) and negatively with maternal age (r =-0.24, P < 0.001). There was a positive correlation between amniotic fluid cortisol with maternal plasma levels (r = 0.32, P < 0.001), which persisted after multivariate analysis controlling for gestation, time of collection and maternal age. The association appeared to be dependent on gestational age, being nonsignificant at 15-16 weeks' gestation and increasing in strength thereafter.

CONCLUSION

This study shows a positive correlation between maternal and amniotic fluid cortisol levels, which becomes robust from 17 to 18 weeks onwards. The results provide support for the hypothesis that alterations in maternal cortisol may be reflected in amniotic fluid levels from this gestation.

A sequential scanning of the immune efficiency in astrocytoma (Grade I to Grade Iii), meningioma and secondary glioma patients with and without therapeutic scheduling

PURPOSE

Glioma induces immune suppression. However, data revealing the immune status in glioma patients with sequential therapeutic interventions is missing. Thus, the study aims at evaluating the sequential immune status of glioma bearing patients (Astrocytoma Grade I to Grade III) receiving conventional therapeutic measures. The results were compared with the immune status of metastatic secondary glioma and meningioma patients where there is minimal immune suppression and the effect of therapeutic intervention on the above score.

METHODS

Functional immune parameters of peripheral blood lymphocytes were assayed by CD2 receptors enumeration through E-rosetting and lymphocyte cytotoxicity assay and assessing the generation of reactive oxygen species by NBT assay of peripheral blood macrophages in patient groups bearing Astrocytoma (Grade I to Grade III), meningioma and secondary glioma.

RESULTS

Patients bearing Astrocytoma (all 3 grades) showed maximum immune suppression as compared to the normal subjects, diseased meningioma controls, and secondary glioma. Therapeutic interventions viz. radiotherapy, surgery and radiotherapy after surgery and chemotherapy could not recover the suppressed activity of the CD2 bearing lymphocytes and that of peripheral blood macrophages. However, therapeutic scheduling could recover the functional activity of the CD8 bearing lymphocytes and the CD56 NK cells from that of tumor bearing patients.

CONCLUSION

Astrocytoma and not meningioma is capable of causing immunesuppression. As the tumor progresses from Grade I to Grade III, a linear reduction in the functional efficacy of immunocytes is seen to occur. Radiotherapy, surgery, and chemotherapy also induces an inhibitory effect towards the host immune system. The inhibitory effect of tumor as well as of therapy were mainly directed towards the CD2 bearing lymphocyte population and the peripheral blood macrophage population.