Ethanol impairs Rho GTPase signaling and differentiation of cerebellar granule neurons in a rodent model of fetal alcohol syndrome

Developmental exposure to ethanol impairs fetal brain development and causes fetal alcohol syndrome. Although the cerebellum is one of the most alcohol-sensitive brain areas, signaling mechanisms underlying the deleterious effects of ethanol on developing cerebellar granule neurons (CGNs) are largely unknown. Here we describe the effects of in vivo ethanol exposure on neurite formation in CGNs and on the activation of Rho GTPases (RhoA and Rac1), regulators of neurite formation. Exposure of 7-day-old rat pups to ethanol for 3 h moderately increased blood alcohol concentration (BAC) ( approximately 40 mM) and inhibited neurite formation and Rac1 activation in CGNs. Longer exposure to ethanol for 5 h resulted in higher BAC ( approximately 80 mM), induced apoptosis, inhibited Rac1, and activated RhoA. Studies demonstrated a regulatory role of Rho GTPases in differentiation of cerebellar neurons, and indicated that ethanol-associated impairment of Rho GTPase signaling might contribute to brain defects observed in fetal alcohol syndrome.

Loose-patch–juxtacellular recording in vivo—A method for functional characterization and labeling of neurons in macaque V1

We describe a method that uses a modified version of juxtacellular labeling [Pinault D. A novel single-cell staining procedure performed in vivo under electrophysiological control: morpho-functional features of juxtacellularly labeled thalamic cells and other central neurons with biocytin or neurobiotin. J Neurosci Meth 1996;65:113-36], which allows us to functionally characterize and subsequently label single neurons in vivo in macaque V1. The method is generally applicable in acute in vivo preparations. Extracellular recording is made with a patch electrode when the electrode is attached to the cell membrane. Initially a 'blind' search method is used as a guide to obtaining a cell attached configuration that we refer to as a loose-patch (LP). The neuron's receptive field properties are functionally characterized, the neuron is labeled and then characterization is confirmed, all in the LP configuration. There are a number of advantages of the method that we describe over other methods. First, we have found that we can obtain stable extracellular recordings for periods of hours that enable us to make a relatively comprehensive visual functional characterization of a neuron's receptive field properties. Second, because the electrode is closely apposed to the cell we obtain excellent isolation of the extracellular spike. Third, the method provides labeling that gives complete dendritic and axonal filling that survives over a number of days, which is an important feature in acute primate experiments. Fourth, the in vivo method of labeling and reconstructing neurons gives complete three-dimensional structure of the neuron including its intra-cortical axonal arbor. These features overcome known limits of the established methods of studying neuronal morphology including the Golgi stain (limited when adult tissue is used) and in vitro whole cell methods (incomplete axonal filling due to limited slice thickness). They also overcome the known limits of the established method of combined function-morphology studies i.e. intracellular recording in vivo. The modified juxtacellular method provides a reliable alternative to the difficult method of characterization by extracellular recording and subsequent intracellular labeling [Anderson JC, Martin KAC, Whitteridge D. Form, function and intracortical projections of neurons in the striate cortex of the monkey Macacus nemestrinus. Cerebral Cortex 1993;3:412-20]. We show the method can be used to record at a range of depths through V1 cortex allowing for sampling of neurons in the different layers and functional subpopulations. Links can then be made with existing knowledge about the anatomical organization of V1, the various morphological classes of neurons found therein, their functional connectivity and visual response properties.

Flow cytometric quantification of antigen D sites on red blood cells of partial D and weak D variants in India

The D antigenic sites are diminished in weak D and partial D variants. The aim of this study was to estimate D antigen on RBC in weak D and partial D variants in Indian population by using flow cytometric method. Blood samples of 42 cases of partial D, eight cases of weak D and 123 normal Rh phenotypes identified by serological methods were used in the study. An indirect immunofluorescence method was employed using 29 monoclonal anti-D as primary antibody. The D antigenic sites were calculated using control RBC as internal standard. The D antigenic sites in weak D and partial D variants are less than that found in normal Rh phenotypes. In weak D, the D antigenic sites were between 1500 and 7000 D antigens per cell. Among partial D variants, DVI had minimum and DVa had maximum number of D sites. Flow cytometry is a very good tool for demonstrating minor variation in D antigen when serological methods are inconclusive. The D antigenic sites per RBC in partial D variants identified in Indian population are reported for the first time.

Percutaneous dilational tracheostomy: an initial experience in community based teaching hospital

Percutaneous dilational tracheostomy (PDT) is frequently performed in the intensive care unit to prevent the long term complications associated with prolonged endotracheal intubation.

OBJECTIVE

To report the analysis of our experience with percutaneous dilation tracheostomy.

STUDY DESIGN

A prospective documentation of 40 patients who received percutaneous dilational tracheostomy in a multidisciplinary intensive care unit during a 12-month period.

METHOD

The patients demographic, indications of intubation and PDT, time required to perform the procedure, complications and the outcome of these patients in the intensive care unit were noted.

RESULT

Among 425 patients, 40 underwent percutaneous dilational tracheostomy that included 22 females and 18 males with the median age of 35 years. Prolonged ventilatory support was the most common indication for tracheostomy. The average duration of intubation before PDT was 5 days. Median procedure time was 20 minutes. Complications included minor bleeding in two (5%), subcutaneous emphysema with pneumothorax in two patients (5%), tracheal stenosis in three (7.5%), tracheo-esophageal fistula and glottic granuloma in one patient each (2.5%). Among forty patients, 28 (70%) were discharged to the ward, 8 died in intensive care unit and 4 left hospital against medical advice.

CONCLUSION

Percutaneous dilational tracheostomy is a safe, quick and effective way for long term airway management in critically ill patients.

Primary anterior abdominal wall actinomycosis

Actinomycosis of the anterior abdominal wall is rare. We report a 50-year-old diabetic man who presented with a left hypochondrial mass of three weeks duration associated with fever. Abdominal computed tomography showed a 2 x 4 cm mass projecting from the internal abdominal wall associated with surrounding inflammation. The mass did not decrease after a week of intravenous antibiotics. Excision of the mass and primary closure of the abdominal wall were performed. The mass involved the deep muscles of anterior abdominal wall. The omentum was adherent to the parietal peritoneum underneath the mass. Microscopical examination of the mass was consistent with actinomycosis. The postoperative period was uneventful and the patient recovered completely. The patient received penicillin for six months.

Kala-azar (visceral Leishmaniasis) from Khotang

Kala-azar is a chronic infection of reticuloendothelial system caused by flagellated protozoan, leishmania donovani injected into human host by the bite of the sand fly (phlebotomous) previously infected by biting and sucking the blood of a patient of leishmaniasis. It is characterized by irregular fever of long duration, large spleen and liver, anaemia, leucopenia and progressive emaciation. This article reports a case of a 10 year old girl from Khotang, a nonendemic zone for Kala-azar, who presented with long history of abdominal distension for 11 months, fever for 9 months, cough for a week and weight loss. Clinical examination revealed pallor, enlarged liver and huge splenomegaly. Investigations confirmed the diagnosis of kala-azar by the presence of L.D bodies in bone marrow smear. The patient is being treated with i.v Amphotericin B in Infectious Disease Hospital, Teku.

Retinoic acid receptors and tissue-transglutaminase mediate short-term effect of retinoic acid on migration and invasion of neuroblastoma SH-SY5Y cells

Long-term treatment with all trans-retinoic acid (RA) induces neuronal differentiation and apoptosis. However, the effect of short-term RA treatment on cell proliferation, migration and invasion of neuroblastoma cell lines (SH-SY5Y and IMR-32) remains unclear. RA induces expression of tissue-transglutaminase (TGase) and promotes migration and invasion after 24 h of treatment in SH-SY5Y cells, but not in IMR-32 cells. RA receptor (RAR) agonist (4-(E-2-[5,6,7,8-tetrahydro-5,5,8,8-tetramethyl-2-naphthalenyl]-1-propenyl) benzoic acid) and RAR/retinoid X receptor (RXR) agonist (9-cis-RA) promote expression of TGase, migration and invasion of SH-SY5Y cells, while RXR agonist has no significant effect. RAR antagonist blocks RA effect on migration and invasion, indicating that RAR receptors are required. Retinoid receptors are expressed and activated by RA in both cell lines. However, only transient activation of RAR is observed in IMR-32 cells. These findings suggest that different responses observed in SH-SY5Y and IMR-32 cells could be due to differential activation of retinoid receptors. Overexpression of TGase has no effect on migration or invasion, while overexpression of antisense TGase blocks RA-induced migration and invasion, indicating that other molecules along with TGase mediate RA effects. In addition to the long-term effects of RA that are coupled with cell differentiation, short-term effects involve migration and invasion of neuroblastoma SH-SY5Y cells.

Evaluation of an automated deformable image matching method for quantifying lung motion in respiration-correlated CT images

We have evaluated an automated registration procedure for predicting tumor and lung deformation based on CT images of the thorax obtained at different respiration phases. The method uses a viscous fluid model of tissue deformation to map voxels from one CT dataset to another. To validate the deformable matching algorithm we used a respiration-correlated CT protocol to acquire images at different phases of the respiratory cycle for six patients with nonsmall cell lung carcinoma. The position and shape of the deformable gross tumor volumes (GTV) at the end-inhale (EI) phase predicted by the algorithm was compared to those drawn by four observers. To minimize interobserver differences, all observers used the contours drawn by a single observer at end-exhale (EE) phase as a guideline to outline GTV contours at EI. The differences between model-predicted and observer-drawn GTV surfaces at EI, as well as differences between structures delineated by observers at EI (interobserver variations) were evaluated using a contour comparison algorithm written for this purpose, which determined the distance between the two surfaces along different directions. The mean and 90% confidence interval for model-predicted versus observer-drawn GTV surface differences over all patients and all directions were 2.6 and 5.1 mm, respectively, whereas the mean and 90% confidence interval for interobserver differences were 2.1 and 3.7 mm. We have also evaluated the algorithm's ability to predict normal tissue deformations by examining the three-dimensional (3-D) vector displacement of 41 landmarks placed by each observer at bronchial and vascular branch points in the lung between the EE and EI image sets (mean and 90% confidence interval displacements of 11.7 and 25.1 mm, respectively). The mean and 90% confidence interval discrepancy between model-predicted and observer-determined landmark displacements over all patients were 2.9 and 7.3 mm, whereas interobserver discrepancies were 2.8 and 6.0 mm. Paired t tests indicate no significant statistical differences between model predicted and observer drawn structures. We conclude that the accuracy of the algorithm to map lung anatomy in CT images at different respiratory phases is comparable to the variability in manual delineation. This method has therefore the potential for predicting and quantifying respiration-induced tumor motion in the lung.

Botrytis grey mould of chickpea: a review of biology, epidemiology, and disease management

Botrytis grey mould (BGM), caused by Botrytis cinerea Pers. ex. Fr., is an economically important disease of chickpea (Cicer arietinum L.), especially in areas where cool, cloudy, and humid weather persists. Several epidemics of BGM causing complete crop loss in the major chickpea-producing countries have been reported. The pathogen B. cinerea mainly survives between seasons on infected crop debris and seeds. Despite extensive investigations on pathological, physiological, and molecular characteristics of B. cinerea causing grey mould type diseases on chickpea and several other hosts, the nature of infection processes and genetic basis of pathogen variability have not been clearly established. This lack of information coupled with the need for repeated application of chemical fungicides forced the deployment of host plant resistance (HPR) as a major option for BGM management. Effective and repeatable controlled-environment and field-screening techniques have been developed for identification of HPR. Of the selected portion of chickpea germplasm evaluated for BGM resistance, only few accessions belonging to both cultivated and wild Cicer spp. were tolerant to BGM, and the search for higher levels of disease resistance continues. Fungicide application based on disease predictive models is helpful in precision-based fungicide application. Integrated disease management (IDM) of BGM has proved more effective than any of the individual disease management components in large-scale, on-farm studies conducted in India, Nepal, and Bangladesh. Further information on the biology of B. cinerea and epidemiology of the disease is needed to strengthen the IDM programs. In this paper the biology of B. cinerea including its variability, epidemiology of BGM, identified sources of resistance, and other management options, and available information on biochemical and genetic basis of disease resistance have been reviewed with a mention of future research priorities.

Structure determination of CdS and ZnS nanoparticles: Direct modeling of synchrotron-radiation diffraction data

We introduce a modified method of powder-diffraction data analysis to obtain precise structural information on freestanding ZnS and CdS nanoparticles with diameters well below 5 nm, i.e., in a range where common bulk-derived approaches fail. The method is based on the Debye equation and allows us to access the crystal structure and the size of the particles with high precision. Detailed information on strain, relaxation effects, stacking faults, and the shape of the particles becomes available. We find significant size differences between our new results and those obtained by established methods, and conclude that a mixed zinc-blende/wurtzite stacking and significant lattice distortions occur in our CdS nanoparticles. Our approach should have direct impact on the understanding and modeling of quantum size effects in nanoparticles.

Growth in children with Helicobacter pylori infection and dyspepsia

AIMS

To compare the height, weight, and body mass index (BMI) of children presenting with dyspeptic symptoms and Helicobacter pylori infection, to those with dyspepsia but without the infection.

METHODS

A retrospective chart review of 257 children was performed. 13C urea breath test was performed to detect H pylori infection; weight and height were recorded and BMI was calculated. Weight, height, and BMI SD scores were determined using the 1990 UK normative data. The Index of Multiple Deprivation 2004 (IMD 2004) scores, which measure deprivation at small area level, were calculated from the patients' postcodes.

RESULTS

Ninety seven of the 257 children were H pylori positive. The mean age at diagnosis and presenting symptoms of H pylori positive and negative patients were similar. The mean IMD 2004 scores for children with H pylori infection were significantly higher compared to H pylori negative patients, suggesting that children with the infection came from relatively more deprived areas. The mean weight and height SD score were significantly lower for children with H pylori infection compared to those without. However, this difference was no longer significant after adjusting for socioeconomic deprivation and ethnic differences between the groups.

CONCLUSION

Children with dyspepsia and H pylori infection were shorter and lighter than patients with similar symptoms but no infection. The differences in anthropometry may be due to socioeconomic and ethnic factors rather than H pylori infection.

Assessment of hypertension control in chronic kidney disease patients by ambulatory blood pressure monitoring

BACKGROUND

Inadequate control of blood pressure (BP) increases cardiovascular mortality and morbidity in chronic kidney disease (CKD) and renal transplant patients. 24 hour ambulatory BP was recorded to evaluate the adequacy of BP control in these patients.

METHODS

60 CKD patients (25 conservative therapy, 16 maintenance hemodialysis, 19 renal transplant patients) were studied prospectively. After achieving clinic BP control, 24 hour ambulatory BP was recorded at 1 and 6 months. The patients were followed up for one year.

RESULTS

Mean daytime and nighttime systolic blood pressure (SBP) both at 1 month and at 6 month was higher in non-survivors than in survivors. The survivors had better control of their daytime (p=0.018) as well as nighttime SBP levels (p=0.018) at 6 months compared to those at 1 month. Survivors achieved nocturnal dipping of SBP at 1 and 6 months (p=0.047, p=0.025, respectively). Non-survivors failed to achieve lower daytime (p=0.375) or nighttime SBP (p=0.254) at 6 months as compared to SBP at 1 month in spite of optimizing antihypertensive therapy. Daytime (p=0.022) and nighttime (p=0.029) diastolic BP (DBP) in the non-survivors was higher than in survivors. Nocturnal dip in DBP was not seen in either survivors at 1 (p=0.177) and 6 months (p=0.434) or non-survivors at 1 (p=0.408) and at 6 months (p=0.081). Renal transplant patients did not exhibit nocturnal dipping of BP.

CONCLUSION

We conclude that, unlike survivors, there was worsening of 24 hour BP control in non-survivors. ABPM has a role in better management of total BP burden in CKD patients.

Prescription auditing and antimicrobial resistance at a tertiary care hospital in New Delhi, India

This paper reports the antibiotic consumption data of Sir Ganga Ram Hospital, New Delhi and bacterial resistance over a seven-year period. Cephalosporins, penicillins and fluoroquinolones were the most widely prescribed antibiotics. A correlation was seen between Escherichia coli resistance to third-generation cephalosporins and increased cephalosporin use, as well as resistance to co-amoxyclav and its use.

Unbiased diffeomorphic atlas construction for computational anatomy

Construction of population atlases is a key issue in medical image analysis, and particularly in brain mapping. Large sets of images are mapped into a common coordinate system to study intra-population variability and inter-population differences, to provide voxel-wise mapping of functional sites, and help tissue and object segmentation via registration of anatomical labels. Common techniques often include the choice of a template image, which inherently introduces a bias. This paper describes a new method for unbiased construction of atlases in the large deformation diffeomorphic setting. A child neuroimaging autism study serves as a driving application. There is lack of normative data that explains average brain shape and variability at this early stage of development. We present work in progress toward constructing an unbiased MRI atlas of 2 years of children and the building of a probabilistic atlas of anatomical structures, here the caudate nucleus. Further, we demonstrate the segmentation of new subjects via atlas mapping. Validation of the methodology is performed by comparing the deformed probabilistic atlas with existing manual segmentations.