USEFULNESS OF EVALUATION OF ANTIMEASLES ANTIBODIES IN PRETERM BABIES

As per WHO recommendations, measles vaccine is administered at the age of 9 months which is based on studies demonstrating seroconversion (from positive to negative) at this age. However this contention may not hold good in preterm babies since they may have lower initial levels of passively transferred IgG antimeasles antibodies of maternal origin. To explore this possibility, 50 preterm babies (gestational age less than 37 weeks) were studied for antimeasles antibodies. Serum samples were collected at birth and then at 3 months and 5 months of age in all the cases. Antimeasles antibody assay was done in all the serum samples using ELISA kits. At birth 32% of infants were positive for antimeasles antibodies whereas 60% were weakly positive and 8% were negative. At 3 months of age 50% were sero negative, 2% positive and 40% weakly positive. The sero negativity was found to be 98% at 5 months with only 2% remaining positive. Since seroconversion is seen to occur in this vast majority of preterm infants at the age of 5 months, antimeasles vaccine should be administered at this age to this subset of more vulnerable babies.

Calculation of excitation functions of nuclides produced in proton induced reactions on NatSi

Excitation functions of several nuclides from p+ NatSi reactions in the incident energy range of 20-110 MeV have been calculated using the hybrid model nuclear reaction code ALICE. Comparisons with experimental data have been made to select proper input options of the code. These data are useful to estimate possible damage in devices containing Si, from the bombardment of solar or accelerator produced protons.

Management of leg ulcers

Leg ulcer is a leading cause of morbidity among older subjects, especially women in the Western world. About 400 years BC, Hippocrates wrote, "In case of an ulcer, it is not expedient to stand, especially if the ulcer be situated on the leg". Hippocrates himself had a leg ulcer. The best treatment of any leg ulcer depends upon the accurate diagnosis and the underlying aetiology. The majority of leg ulcers are due to venous disease and/or arterial disease, but the treatment of the underlying cause is far more important than the choice of dressing. The aetiology, pathogenesis, treatment, and the future trends in the management of the leg ulcers are discussed in this review.

Reduced expression and altered distribution of neurofilaments in neurons cultured in thyroid hormone-deficient medium

The effect of thyroid hormone (TH) deficiency on the expression of neurofilament (NF) proteins and their intracellular distribution has been examined in primary cultures of neurons from embryonic rat cerebra. Northern blot analysis showed that in TH-deficient (THdef) neurons, the expression of all three NF mRNAs (NF-L, NF-M and NF-H) are retarded by 50-70% at days 7, 15 and 25 of culture compared with their TH-supplemented (THsup) counterparts. Western blot analysis also showed a decline of 60-80% in the expression of all the NF-proteins at all time points. Immunofluorescent staining of neurons from THdef and THsup cultures at days 7, 15, and 25 with monoclonal anti NF-L antibody showed that with age, TH deficiency reduced the localization of NF-L in the cell body with a corresponding increase in the hillock and proximal axon region. The present neuronal culture system offers an excellent experimental model for studying the biochemical events responsible for the altered NF pathology in degenerating neurons.

Management of urinary incontinence

Urinary incontinence is one of the most embarrassing disabilities in the elderly people. It may be defined as an involuntary loss of urine in a quantity or frequency sufficient to cause a social or hygienic problem. Its magnitude is both overlooked and underestimated by the medical community. Unfortunately, urinary incontinence lacks the glamour of other 'high tech' medical problems.

Concepts in computation of preequilibrium neutron emission from heavy ion reactions

Integral forms of the Boltzmann-like transport equations are derived to treat neutron emissions from heavy ion collisions. The derivations are based on the probability of contribution (score) from nucleon occupied phase space bins to the double differential emission spectra. Two-body interactions among the nucleons in "hot spot" and "cold spot" regions of the composite system resulting in creation, annihilation, or energy redistribution of the colliding particles are considered. The resulting equations are solved numerically in energy-angle bins to study thermal and kinematic equilibrium of the target + projectile (165Ho+20Ne) excited system at different projectile energies (10 MeV/A to 30 MeV/A).

Anti-angiogenic cues from vascular basement membrane collagen

Vascular basement membrane is an important structural component of blood vessels and has been shown to interact with and modulate vascular endothelial behavior during angiogenesis. During the inductive phase of tumor angiogenesis, this membrane undergoes many degradative and structural changes and reorganizes to a native state around newly formed capillaries in the resolution phase. Such matrix changes are potentially associated with molecular modifications that include expression of matrix gene products coupled with conformational changes, which expose cryptic protein modules for interaction with the vascular endothelium. We speculate that these interactions provide important endogenous angiogenic and anti-angiogenic cues. In this report, we identify an important antiangiogenic vascular basement membrane-associated protein, the 26-kDa NC1 domain of the alpha1 chain of type IV collagen, termed arresten. Arresten was isolated from human placenta and produced as a recombinant molecule in Escherichia coli and 293 embryonic kidney cells. We demonstrate that arresten functions as an anti-angiogenic molecule by inhibiting endothelial cell proliferation, migration, tube formation, and Matrigel neovascularization. Arresten inhibits the growth of two human xenograft tumors in nude mice and the development of tumor metastases. Additionally, we show that the anti-angiogenic activity of arresten is potentially mediated via mechanisms involving cell surface proteoglycans and the alpha1beta1 integrin on endothelial cells. Collectively, our results suggest that arresten is a potent inhibitor of angiogenesis with a potential for therapeutic use.

Assessment of the need for a training course in rational use of drugs: a cross-sectional pilot study

Rational use of drugs means need-based use of them keeping in mind the pathological status, therapeutic indices, drugs interactions and adverse drug reactions. Lacunae in the existing undergraduate curriculum cause irrational use of drugs. The present study was undertaken among 2,200 fresh medical graduates from all over the country with a list of questionnaire distributed among them and analysing the answers. The aim was to ascertain the adequacy of present undergraduate curriculum on pharmacology in equipping the doctors on rational use of drugs and to assess the need and feasibility of Refresher's course. More than half (55%) replied prescriptions were not truly rational. Ninety-eight per cent opened Refresher's course is beneficial in rational prescribing. This cross-sectional survey could provide a glimpse of existing undergraduate pharmacology curriculum and its impact on rational prescribing practice. The Refresher's course in the early internship period involving the clinical departments and department of pharmacology is suggested.

Thyroid hormone-induced maturation of astrocytes is associated with the expression of new variants of vimentin and their phosphorylation

The role of thyroid hormone (TH)-induced vimentin expression in promoting the maturation of astrocytes has been investigated. Comparative immunocytochemical staining with vimentin antibody demonstrated distinctly different patterns of expression of vimentin during the progressive maturation of astrocytes of normal and TH-deficient astrocyte cultures. [35S]Methionine labeling of cells showed a significant decline in the level of vimentin in the hypothyroid cultures at all ages from day 5 to 20. Western blot analysis suggested that the maturation of normal astrocytes was associated with the appearance of several acidic and basic variants of vimentin, whose expression was significantly delayed or reduced in the TH-deficient astrocytes. In normal astrocyte cultures, two acidic variants of vimentin, one of similar molecular weight and the other of lower molecular weight, were found to be phosphorylated during the final transformation of the epithelioid form into the mature stellate form. None of these phosphorylated forms was evident in the TH-deficient astrocytes. This was further confirmed by negative immunocytochemical staining of 5- to 18-day-old cultures of TH-deficient astrocytes with antibody TM71, specific to phosphorylated vimentin, compared with age-matched normal astrocytes, which displayed consistent positive staining. The overall results indicate that TH-induced expression of phosphorylated forms of vimentin may be essential for the intracellular organization of the cytoskeleton in a way conducive to the morphological maturation of astrocytes.

Can lowering homocysteine levels reduce the incidence of stroke?

Hyperhomocysteinaemia has been identified as an independent risk factor for atherosclerotic and thromboembolic diseases such as cerebro-vascular diseases, coronary artery disease and venous thrombosis. This review will discuss the role of high levels of plasma homocysteine in stroke disease.

Surrogate endpoints: do they really contribute in therapeutic decision making?

Surrogate endpoints are substitutes for the true endpoints and measured in any clinical research to relate in some way to the outcome of primary interest. Inappropriate selection of surrogate markers may lead to controversies during clinical trials or therapeutic interventions. Use of surrogate markers depends upon thorough understanding of the pathophysiology of the disease and pharmacology of drugs. Results obtained with surrogates should be regarded as preliminary and necessitates definitive studies.

Regulation of neurofilament gene expression by thyroid hormone in the developing rat brain

The role of thyroid hormone (TH) in the expression of neurofilament (NF) genes during the first 3-4 postnatal weeks of rat brain development has been examined. I.p. administration of TH to 2-day-old hypothyroid rats resulted in a 2-fold increase in cerebral NF-M and NF-L mRNAs, while administration to 15-day-old hypothyroid rats led to a 1.5- to 3-fold increase in NF-H mRNA within 2-4 h of hormone injection. Comparison of the level of these mRNAs in cerebra from 5, 10, 15 and 20-day-old normal and hypothyroid rats by Northern blot analysis revealed that hypothyroidism declined the expression of all three mRNAs by 50-70% at all ages examined. Western blot analysis of total protein and cytoskeletal proteins isolated from cerebras of 5, 10, 15, 20 and 25-day-old normal and hypothyroid rats demonstrated an even greater reduction (60-90%) in the expression of NF proteins in the hypothyroid cerebra during the period examined. The overall results show that TH plays an important role in regulating the expression of all three NF genes during rat brain development.

STUDY OF GLOMERULAR FUNCTIONS IN NEONATES

Glomerular function of neonates (25 full term and equal number of preterm neonates) at birth, on day seven and day fourteen were estimated by endogenous Creatinine clearance (CCr). The Preterm were divided into three groups viz. Group I (Gestation age (GA) 30-32 weeks), Group II (GA 33-34 weeks) and Group III (GA 35-36 weeks). Group IV consisted of 25 term neonates. Serum creatinine (in mg/dl) in all the groups of preterm ranged from 0.92 ± 0.153 to 1.204 ± 0.154 and in term neonate from 0.562 ± 0.175 to 1.148 ± 0.247 showing that the levels were inversely proportional to the period of gestation. Besides the Serum Creatinine levels in all groups of Preterm as well as term neonates were found to fall significantly (p < 0.001) during the first and second week. Glomerular filtration rate (GFR) in Group I were 16.603 ± 2.519, 19.786 ± 2.078 and 23.720 ± 2320 on day one, seven and fourteen respectively showing progressive improvement during the first two weeks. The GFRs were also found to be directly proportional to the GA. In addition the levels of GFR were found increasing significantly during the second week compared to that on day seven in all the groups of preterm neonates. GFR's in Group I & II on all the three occasions were significantly lower (p < 0.001) than those of term counterparts, however the GFR on the first day in Group III neonates was lower than group IV, the difference was insignificant (p > 0.05). The increase in GFR in Group I on the three occasions was linear but insignificant (p > 0.05). The rise was more rapid & significant (p < 0.001) during the second week in Groups II & III. On the contrary the rate of improvement of GFR in full terms was quite rapid during the first week and gradual over the second week of life.

Tubulin and glial fibrillary acidic protein gene expression in developing fetal human brain at midgestation

Developmental alterations in the expression of glial fibrillary acidic protein (GFAP) and alpha-tubulin were examined at the level of mRNA and protein in human fetal brain between weeks 13-23 of gestation. Except for a transient increase at week 15, GFAP expression in the cytoskeletal (CSK) fraction was low until week 17, when it increased steadily to week 23, corresponding to the phase of glial proliferation. The developmental profile of alpha-tubulin in the CSK fraction displayed a biphasic pattern, with an initial rise between weeks 13-16 coinciding with the early phase of neuroblast multiplication, and a second rise between weeks 17-23 corresponding to the phase of glial proliferation. No significant difference in the spatial distribution of alpha-tubulin was found in different region of brain but GFAP expression varied with a higher level in cerebellum than that in cerebrum at late midgestation.

Protein kinase A linked phosphorylation mediates triiodothyronine induced actin gene expression in developing brain

In the developing rat cerebra, triiodothyronine (T3) stimulates actin mRNA by acting predominantly at the level of transcription whereas tubulin mRNA is enhanced primarily by post-transcriptional regulation. We report here that in primary cultures of rat cerebra, the T3-induced actin gene expression is mediated by phosphorylation events. Inhibition of protein kinase A (PKA), but not of protein kinase C (PKC) or tyrosine kinase, totally blocked the induction of actin mRNA by T3. Under identical conditions, induction of tubulin mRNA by T3 was virtually unaffected by all the inhibitors. Activators of PKA, but not of PKC, potentiated the T3-induced actin gene expression, both at mRNA and protein level, by about 2-fold. In the absence of T3, neither the inhibitor nor the activator of PKA had any significant effect on this induction. The involvement of PKA in mediating the induction of actin mRNA by T3 was confirmed by transfecting primary cultures of rat cerebra with an expression vector encoding the protein kinase A inhibitor which totally abolished the induction. T3 is shown to enhance the phosphorylation of the thyroid hormone receptor, TRalpha, by about 2-fold but the level of phosphorylation of TRbeta remained virtually unaffected.

Specific binding of L-triiodothyronine modulates Na(+)-K(+)-ATPase activity in adult rat cerebrocortical synaptosomes

Interactions of L-triiodothyronine (T3) in adult rat cerebrocortical synaptosomes were studied in vitro. Scatchard plot analysis revealed two sets of T3 binding sites. The degree of saturation of T3 binding sites (putative receptor) correlated well with the dose-dependent inhibition of Na(+)-K(+)-ATPase activity in synaptosomes. The relative binding affinities and relative inhibition of enzyme activities for different TH analogues were L-T3 > T3-amine > TRIAC = L-T4 > r-T3 > T2 and L-T3 > T3-amine > TRIAC > L-T4 > r-T3 > T2, respectively. The present study demonstrates the nature of inhibition of synaptosomal Na(+)-K(+)-ATPase activity may be as a function of T3 occupancy of synaptosomal receptor sites in adult mammalian brain.

Role of Anopheles culicifacies during an outbreak of malaria in Gorubandha P.H.C., Assam

Entomological investigation during an outbreak of malaria in Gorubandha PHC in Sonitpur district revealed unusually high density of Anopheles culicifacies followed by An.minimus. Parity rates of both the species were very high, 65% and 62.2% respectively. An. culicifacies was incriminated as malaria vector. Sporozoite rate recorded was 0.63%. Both the species were found susceptible to DDT. This substantiates the epidemiological observation which yielded 98% Plasmodium falciparum malaria out of 35.2% malaria positive cases. Incrimination of An. culicifacies means adding one more malaria vector to this region.

Regulation of actin and its mRNA by thyroid hormones in cultures of fetal human brain during second trimester of gestation

The effect of thyroid hormones (THs) on the expression of actin gene during fetal human brain development and the period of sensitivity to the hormones have been investigated. Developmental profile of actin in the cytoskeletal (CSK) and noncytoskeletal (non-CSK) fractions in the fetal cerebra showed a pronounced rise in the level of CSK actin at weeks 17-19. Northern blot analysis also revealed a sharp rise in the level of actin mRNA at weeks 16-18, temporally coinciding with the period of rise of THs and peak expression of TH receptors in the fetal brain. In organ cultures of weeks 13-23 fetal cerebra, THs elicited a general stimulation of CSK proteins at all ages studied with a preferential effect on actin at weeks 17-19. During this period, THs also stimulated the rate of synthesis of actin. Kinetics of induction of actin by TH in the non-CSK and CSK fractions in organ cultures of week 17 fetal cerebra showed an increased level of actin in both fractions within 1 h. Subsequently (at 5 and 18 h), induction was evident only in the insoluble CSK fraction, suggesting an effect of the hormone on the intracellular distribution of actin between the soluble non-CSK fraction and the insoluble CSK fraction. Correspondingly, in cultures of week 17 fetal cerebra, THs elicited an increase in actin mRNA level within 30 min of hormonal exposure. The overall results suggest that THs regulate the expression of actin gene by stimulating the rate of synthesis as well as intracellular distribution of actin during the mid phase of the second trimester of gestation.

Regulation of cytoskeletal proteins by thyroid hormone during neuronal maturation and differentiation

Primary cultures of neurons from 16- to 17-day-old embryonic rat cerebra were maintained for 3 weeks in thyroid hormone deficient (THdef) and thyroid hormone supplemented (THsup) media to investigate how TH regulates the cytoskeletal (CSK) proteins during neuronal differentiation and maturation. Two distinct phases of regulation of triton-insoluble CSK-proteins by TH were discernible--an early phase (days 4-8 of culture) when TH-deficiency resulted in down-regulation of these proteins and a late phase (days 16-20) involving up-regulation of these proteins. In contrast, the triton-soluble non-CSK proteins always remained up-regulated by TH. The two main effects of TH-deficiency were retarded neurite outgrowth and altered neuronal morphology. Of all the CSK proteins, actin was found to be predominantly sensitive. Alterations in the level of CSK actin during neuronal maturation were found to be parallel to changes in steady-state level of actin mRNA as well as actin synthesis. However, these TH-induced changes (up-regulation of actin during the early phase and down-regulation during the late phase) did not lead to parallel changes in the level of soluble G-actin which was comparable at both days 8 and 16 in THdef and THsup cultures. Quantitation of different forms of intracellular actin revealed that G-actin level declined by about 50% between days 8 and 16. In the case of THsup neurons, this reduction in G-actin was accompanied by a parallel increase in the non-CSK F-actin, whereas TH-deficiency resulted in a corresponding increase in CSK F-actin during the terminal differentiation of neurons. Thus TH regulates the biogenesis of CSK-proteins with a predominant effect on actin and the transformation of G-actin into non-CSK F-actin appears to be the key step in neuronal maturation which is affected by hypothyroidism.

Regulation of beta- and gamma-actin mRNA by thyroid hormone in the developing rat brain

The relative sensitivity of the two isotypes of actin mRNA (beta and gamma) to thyroid hormone (T3) was examined by comparing the steady state levels of these mRNAs with their rates of transcription in cerebra from normal and hypothyroid rats of different ages, covering the period of synaptogenesis (days 1-20 postnatal). Hypothyroidism was associated with a reduction in the steady state level of beta-actin mRNA during the entire period, but levels of gamma-actin mRNA were reduced only during the early phase of synaptogenesis (first week). The rats of transcription of both beta- and gamma-actin mRNAs were stimulated by T3 during the early phase but that of beta-actin mRNAs was relatively more sensitive to T3 than gamma-actin mRNA. The lack of correlation between the rates of transcription of beta- and gamma-actin mRNA at different ages with their corresponding steady-state levels suggests additional post-transcriptional regulation.

Role of thyroid hormone in the morphological differentiation and maturation of astrocytes: temporal correlation with synthesis and organization of actin

Morphological changes and the molecular mechanisms associated with the maturation of astrocytes were studied under normal and thyroid hormone-deficient conditions using long-term (30 days) primary cultures derived from the neonatal rat brain. Immunocytochemical staining of cells with a monoclonal antibody specific to glial fibrillary acidic protein demonstrated for the first time that, similar to their maturation in vivo, astrocytes maintained in normal serum-containing medium can undergo complete maturation involving two distinct stages of morphological differentiation (from radial glia to flat polygonal cells with epithelioid morphology and then to mature process-bearing cells with stellate morphology). Deficiency of thyroid hormone delays the first step and totally blocks the second stage of differentiation in the maturation process. Comparative staining of normal and thyroid hormone-deficient astrocytes with filamentous actin-specific fluorescein isothiocyanate-phalloidin and quantitation of the various forms of intracellular actin using an improved DNase I assay demonstrated that maturation of astroglial cells is associated with characteristic alterations in the level of cytoskeletal and noncytoskeletal filamentous (F) actin. In particular, the maintenance of the epithelioid form of the hypothyroid astrocytes is associated with a progressive increase in the level of cytoskeletal F-actin and a concomitant decline in the level of non-cytoskeletal F-actin. Quantitation of actin mRNA by Northern blot analysis and studies on the rate of actin synthesis at various stages of differentiation showed that the initial transformation into the epithelioid form is associated with an increase in the rate of synthesis of actin and the expression of its mRNA, while the final transformation into the nature process-bearing form is correlated with a decline in these parameters. The results indicates that thyroid hormone plays an obligatory role in promoting the differentiation and maturation of astrocytes, and that during this process the hormone regulates the expression of actin and its intracellular organization in a way conducive to morphological differentiation.

Microbiology of mesu, a traditional fermented bamboo shoot product

The use of mesu as a pickle and as the base of curry is a tradition in the Darjeeling hills and Sikkim of India. A total of 327 strains of lactic acid bacteria, representing Lactobacillus plantarum, L. brevis and Pediococcus pentosaceus were isolated from 30 samples of mesu. These species were present in all samples of raw bamboo shoots tested. Mesu was dominated by L. plantarum followed by L. brevis; P. pentosaceus was isolated less frequently and recovered from only 40-50% of the mesu samples. The fermentation was initiated by P. pentosaceus, followed by L. brevis, and finally succeeded by L. plantarum species. During fermentation, the titratable acidity increased from 0.04 to 0.95%, resulting in the decline in pH from 6.4 to 3.8.