Effect of gamma (γ-) radiation on the opto-structural and morphological properties of green synthesized BaO nanoparticles using Moringa Oleifera leaves

In this current assessment, BaO synthesized from Moringa Oleifera leaves were irradiated using 0-75 kGy gamma radiation and investigated its physical impacts. The x-ray diffraction (XRD) data demonstrated the synthesis of tetragonal BaO, and no phase deviation was observed after irradiation. As doses are increased, the overall crystallite size were decreased due to an increase in defects and disorders. The tetragonal BaO was evident in Fourier transform infrared (FTIR) spectra prior to and following irradiation, while peak intensities and wavenumbers varied considerably. The as-prepared BaO showed a spherical shape morphology, and Field emission scanning electron microscopy (FESEM) indicated no vital deviations in it after irradiation. As irradiation shifts from 0 to 75 kGy, optical bandgap was increased from 4.55 to 4.93 eV, evaluated using Kubelka-Munk (K-M) equation from UV-vis-NIR spectrophotometer. Opto-electronic and photonic devices have challenges in extreme radiation conditions, such as space and nuclear environments. So, these assessments suggested that BaO can withstand high levels of gamma photon and could be a good option for photonic and optoelectronic instruments in an extreme gamma-ray exposed conditions.

TB prevalence among patients with diabetes in Bangladesh

OBJECTIVE: 1) To assess the prevalence of TB among patients with diabetes mellitus (DM) attending diabetic care centres in Bangladesh, and 2) to compare TB- and DM-related sociodemographic and other factors in diabetic patients who had TB and those who did not.METHODS: This cross-sectional study was conducted from 1 June 2019 to 31 March 2020 in 108 centres of the Diabetic Association of Bangladesh (BADAS), with a sample size of 3,649 patients with DM. Data were collected by face-to-face interview using semi-structured questionnaire from each patient/guardian. Other ethical issues were also maintained.RESULTS: Out of 3,649 patients with DM, 676 presumptive TB cases were identified and tested; from them, 85 patients were detected as TB cases. Another 39 patients were already diagnosed and on anti-TB medication. Prevalence of TB among patients with DM attending diabetic care centres was 3.4%. Prevalence was higher in female than male (4.0% vs 2.6%). Underweight (9.0%) patients and patients having diabetes for more than 10 years (7.1%) had a higher prevalence of TB.CONCLUSION: TB prevalence was over 3% among study population with DM. Periodic screening and active case finding among DM patients should be strengthened to reduce the risk of TB infection among DM patients.

Investigation on structure, thermodynamic and multifunctional properties of Ni–Zn–Co ferrite for Gd3+ substitution

This study presents a modification of structure-dependent elastic, thermodynamic, magnetic, transport and magneto-dielectric properties of a Ni–Zn–Co ferrite tailored by Gd³⁺ substitution at the B-site replacing Fe³⁺ ions. The synthesized composition of Ni_0.7Zn_0.2Co_0.1Fe_2−xGd_xO₄ (0 ≤ x ≤ 0.12) crystallized with a single-phase cubic spinel structure that belongs to the Fd3̄m space group. The average particle size decreases due to Gd³⁺ substitution at Fe³⁺. Raman and IR spectroscopy studies illustrate phase purity, lattice dynamics with cation disorders and thermodynamic conditions inside the studied samples at room temperature (RT = 300 K). Ferromagnetic to paramagnetic phase transition was observed in all samples where Curie temperature (T_C) decreases from 731 to 711 K for Gd³⁺ substitution in Ni–Zn–Co ferrite. In addition, Gd³⁺ substitution reinforces to decrease the A-B exchange interaction. Temperature-dependent DC electrical resistivity (ρ_DC) and temperature coefficient of resistance (TCR) have been surveyed with the variation of the grain size. The frequency-dependent dielectric properties and electric modulus at RT for all samples were observed from 20 Hz to 100 MHz and the conduction relaxation processes were found to spread over an extensive range of frequencies with the increase in the amount of Gd³⁺ in the Ni–Zn–Co ferrite. The RLC behavior separates the zone of frequencies ranging from resistive to capacitive regions in all the studied samples. Finally, the matching impedance (Z/η₀) for all samples was evaluated over an extensive range of frequencies for the possible miniaturizing application.

This study presents a modification of structure-dependent elastic, thermodynamic, magnetic, transport and magneto-dielectric properties of a Ni–Zn–Co ferrite tailored by Gd³⁺ substitution at the B-site replacing Fe³⁺ ions.

National Clinical Guidance for the Management of Cardiovascular Intervention in the COVID-19 Pandemic: From Bangladesh Society of Cardiovascular Interventions (BSCI)

Since the first recorded case of SARS-CoV-2 in Bangladesh on 8th March 2020, COVID-19 has spread widely through different regions of the country, resulting in a necessity to re-evaluate the delivery of cardiovascular services, particularly procedures pertaining to interventional cardiology in resource-limited settings. Given its robust capacity for human-to-human transmission and potential of being a nosocomial source of infection, the disease has specific implications on healthcare systems and health care professionals faced with performing essential cardiac procedures in patients with a suspected or confirmed diagnosis of COVID-19. The limited resources in terms of cardiac catheterization laboratories that can be designated to treat only COVID positive patients are further compounded by the additional challenges of unavailability of widespread rapid testing on-site at tertiary cardiac hospitals in Bangladesh. This document prepared for our nation by the Bangladesh Society of Cardiovascular Interventions (BSCI) is intended to serve as a clinical practice guideline for cardiovascular health care professionals, with a focus on modifying standard practice of care during the COVID-19 pandemic, in order to ensure continuation of adequate and timely treatment of cardiovascular emergencies avoiding hospital-based transmission of SARS-COV-2 among healthcare professionals and the patients. This is an evolving document based on currently available global data and is tailored to healthcare systems in Bangladesh with particular focus on, but not limited to, invasive cardiology facilities (cardiac catheterization, electrophysiology & pacing labs). This guideline is limited to the provision of cardiovascular care, and it is expected that specific targeted pharmaco-therapeutics against SARS-CoV-2 be prescribed as stipulated by the National Guidelines on Clinical Management of Corona virus Disease 2019 (COVID-19) published by the Director General of Health Services, Ministry of Health and Family Welfare of Bangladesh.

Anterior Mediastinal Teratoma- A Rare Variety

Anterior mediastinal teratomas are rare germ cell tumors. We report a case of such rare tumor in a 16 years old boy who presented with sudden severe right sided abdominal pain which radiating to chest for one day. CT scan of the chest was suggestive of anterior mediastinal teratoma. Patient underwent Clamshell thoracotomy. Peroperatively a large mass was found in the anterior mediastinum containing huge amount of sebum like material. It was adherent to mediastinal surface of right & left lung, pericardium and great vessels (SVC, Aorta). The tumor and was resected out except part of its posterior surface which was adherent to pericardium and great vessels and was left in situ. He had a smooth & uneventful post-operative recovery. Histopathology reported as mature (benign) teratoma with no evidence of malignancy.Pulse Vol.10 January-December 2017 p.52-56

Pseudomyxomaperitonei: A Rare Clinical Entity - A Case Report

Pseudomyxomaperitonei (PMP) is a rare disease characterized by presence of gelatinous ascites and mucinous implants on the peritoneum and omentum. We report the case of a 58 years old woman with primary tumour of the appendix and secondary involvement of other structures & organs of abdominal cavity. Aim of this case report is to create awareness among the clinicians regarding this uncommon disease presented with ascites and irregular masses in the abdomen. In addition, literature on the clinical presentation, diagnostic procedures, and treatment options has been briefly reviewed.Pulse Vol.10 January-December 2017 p.47-51

Status of Hearing Impairment among Handloom Workers in Tangail District of Bangladesh

Industrial noise is one of the major sources of noise pollution. Handloom industry is the biggest handicraft industry in our country; it is the second largest source of rural employment after agriculture. The workers of the handloom industry worked within excessive level of sound. This cross-sectional study was an attempt to see the status of hearing impairment among handloom worker at Tangail District, Bangladesh from August 2016 to December 2016. A total 180 handloom workers were included in this current study. All the respondents were male as handloom work is a strenuous work. The mean age of respondents was 38.18±11.529 years where most of the respondents were of middle age group (21-50) year's age group. Among the participants less than one-fourth was illiterate and rest had primary to secondary level of education. The average income of handloom workers was 13805.56±2764.696 BDT per month. Handloom workers spend average 10 hour for working per day. They were exposed to sound beyond NIOSH recommendation (70-83 dB around handloom machines and 80-90 dB around power loom machines). By self-assessment hearing impairment perception 76.7% participants reported that they had hearing problem. Based on the interpretation of Rinne, Webers and ABC test data indicate that among the respondents around 32.2% were identified with bilateral sensorineural hearing impairment and of them through Pure tone audiometry (PTA) around half were diagnosed as suffering from moderate to severe Noise induced hearing loss (NIHL). Using personal protective measure like ear muffle/ear musk has been recommended.

Room-temperature ferromagnetism in Ni(ii)-chromia based core–shell nanoparticles: experiment and first principles calculations

We have synthesized bimagnetic core–shell nanoparticles containing a first-of-its-kind Ni(ii)-chromia nanophase shell and a well-defined, epitaxial core–shell interface.

Evaluation of serum lipid profile in patients with hypertension living in a coastal region of Bangladesh

Serum lipid levels are greatly controlled by genetic and environmental factors. When investigating the relationship between lipid disturbances and hypertension it is necessary to use local data on blood lipid profile in each region. Unfortunately, there is no literature reporting the lipid profile in hypertensive patients in coastal region of Bangladesh. The present study was conducted as a case-control study with 100 hypertensive patients as cases and equal number of normotensive individuals as controls. Socio-demographic, anthropometric and clinical data of both patients and controls were collected. Serum lipid parameters were analyzed biochemically. Independent sample t-test, Chi-Square test and Pearson's correlation test were done for the statistical analysis using the statistical software package SPSS. Our study found that serum total cholesterol (TC), triglyceride (TG), LDL, VLDL, TC/HDL, LDL/HDL were significantly higher (p<0.05) whereas the level of HDL cholesterol was significantly lower in hypertensive patients as compared to control subjects (p<0.05). Pearson's correlation analysis reveals that HDL cholesterol was inversely correlated with systolic and diastolic blood pressure in both patient and control groups. But serum TC, TG, LDL and HDL cholesterol were directly correlated with systolic and diastolic blood pressure in both groups. This study explored that hypertensive patients have higher level of TC, TG, LDL and VLDL cholesterol but lower level of HDL cholesterol than the normotensive subjects. Routine investigation of lipid profile in hypertensive patients may help to prevent further aggravation and risks of coronary artery diseases.

Ecology of Cyprinus carpio var. specularis (Physico-Chemical Conditions of the Habitat)

The study was carried out from November 2010 to August 2011. The study was conducted on the Atrai river, a flood plain and a culturable pond of Naogaon district for the find out of ecology of Cyprinus carpio var. specularis. The mean values of air temperature of Atrai river, flood plain and pond was 28.17. The mean values of water temperature of Atrai river, flood plain and pond was 26.39, 26.61 and 25.81°C, respectively. The mean values of water transparency of Atrai river, flood plain and pond was 57.25, 47.20 and 41.32cm, respectively. The mean values of rainfall of Atrai river, flood plain and pond was 121.19. The mean values of pH of Atrai river, flood plain and pond was 8.03, 7.91 and 7.73, respectively. The mean values of DO of Atrai river, flood plain and pond was 5.99, 6.43 and 5.93 mg/l, respectively. The mean values of CO2 of Atrai river, flood plain and pond was 6.87, 6.87 and 6.77 mg/l, respectively. DOI: http://dx.doi.org/10.3329/jsf.v9i1-2.14656 J. Sci. Foundation, 9(1&2): 133-139, June-December 2011

Food and Feeding Habit of Cyprinus carpio var. specularis

The study was carried out from November 2010 to August 2011. A total of 137 specimens of Cyprinus carpio var. specularis were collected from Naogaon municipal fish market, Shabi hat fish market, Niamatpur fish market and directly from the culture pond of Naogaon district The month-wise collection and experiments were made to show the seasonal variation in food choice, and feeding habit of the fish. The highest percentage of empty stomach was in the month of April 2011 (56.67%) and the lowest percentage of empty stomach was in the month of August 2011 (26.32%). The highest percentage of full stomachs was found in the month of August 2011 (73.68%) and the lowest percentage of full stomachs was found in April 2011 (43.33%). The analysis of stomach contents of C. carpio var. specularis revealed that the food of the fish consists of aquatic plant parts (20.12%), phytoplankton (16.46%), zooplankton (19.69%), debris and detritus (22.00%), insects (6.78%) and semi-digested materials (14.83%). The highest percentage (33.26%) of aquatic plant parts were observed in June 2011 and the lowest percentage (8.80%) in December 2010. The average total length was 37.83±6.96 cm and the average alimentary canal length was 100.63±7.89 cm. DOI: http://dx.doi.org/10.3329/jsf.v9i1-2.14658 J. Sci. Foundation, 9(1&2): 163-169, June-December 2011

Environmental Impact Assessment of Fish Diseases on Fish Production

The present research work was conducted from July 2008 to June 2009 to investigate intensity of infestation of parasites in freshwater fishes and the impact of fish diseases on fish production in northern region of Bangladesh. Possibility of out break of diseases due to deterioration of environmental factors of water bodies was included in this study. The diseases identified were ulcer diseases, EUS (Epizootic Ulcerative Syndrome), Ichthyophthiriasis, Trichodiniasis, Chilodoneliasis, Myxoboliasis, Dactylogyrosis, Gyrodactylosis, Argulosis, Pernicious anaemia, Red spot disease, Red Pest of freshwater eel, Mouth fungus, Branchiomysis, Abdominal dropsy and whirling disease. The infestation more occurred in young fishes than in adult fishes. The overall water qualities of water bodies fluctuated from July 2008 to June 2009. Physicochemical parameters have more or less significant combined effect on the deterioration of water quality as well as fish diseases. Gills were the most affected sites and parasites damaged gill filaments by rupturing blood capillaries, causing necrosis, coagulation and hemorrhage. The present study revealed the prevalence of different organisms in fishes, which are potential pathogen for them. Fishes were infested by parasites and other pathogens. From overall study it was observed that the parasites, bacteria and fungus were most important pathogen for outbreak of diseases. It was also observed that there was a direct relation between disease outbreak among fishes and environmental factors. Low alkalinity reduces the buffer capacity of water and badly affects the pond ecosystem, which in turn cause stress to the fish and become more susceptible to diseases. In case of low aquatic environmental temperature fish reduces metabolic activities, which in turn makes the fish more susceptible during the winter period towards parasitic infection. DOI: http://dx.doi.org/10.3329/jsf.v9i1-2.14655 J. Sci. Foundation, 9(1&2): 125-131, June-December 2011

Nature of weak magnetism in SrTiO3/LaAlO3 multilayers

We report the observation of weak magnetism in superlattices of LaAlO(3)/SrTiO(3) using β-detected nuclear magnetic resonance. The spin lattice relaxation rate of ^{8}Li in superlattices with a spacer layers of 8 and 6 unit cells of LaAlO(3) exhibits a strong peak near ~35 K, whereas no such peak is observed in a superlattice with spacer layer thickness of 3 unit cells. We attribute the observed temperature dependence to slowing down of weakly coupled electronic moments at the LaAlO(3)/SrTiO(3) interface. These results show that the magnetism at the interface depends strongly on the thickness of the spacer layer, and that a minimal thickness of ~4-6 unit cells is required for the appearance of magnetism. A simple model is used to determine that the observed relaxation is due to small fluctuating moments (~0.002μ(B)) in the two samples with a larger LaAlO(3) spacer thickness.

Tubercular lymphadenitis - diagnostic evaluation

Tuberculosis is one the commonest disease affecting peripheral lymph node and cervical tubercular lymphadenitis are frequently encountered in Otolaryngological practice. Three hundred fifty six (356) cases of Fine Needle Aspiration for Cytology (FNAC) positive tubercular lymphadenitis were studied from January 2006 to December 2008. FNAC positive but histopathologically negative cases were excluded from the study. Among 356 cases of FNAC positive cervical lymphadenopathy 300 cases (84.27%) were confirmed tuberculosis on histopathological examination. Remaining 50 cases (15.73%) were diagnosed as nontubercular lymphadenitis where nonspecific lymphadenitis was the commonest finding 34(9.55%) followed by metastatic carcinoma 7(1.97%), lymphoma 6(1.08%), Kikuchiz's disease 6(1.08%), Kala-Azar 2(0.56%) & Leukemia 1(0.28%). Most of the patients presented with only multiple lymph node swelling with other symptoms, such as fever 18(5.06%), pain (15.7%), tenderness 53(14.88%), weight loss 29(8.14%), anorexia 33(9.26%). Following observations are evident from this study: i) Disease is comparatively common between 12-35 years ii) Multiple matted/discrete lymph nodes are the earliest presentation iii) Multiple lymph node is the most consistent finding for clinical diagnosis. iv) Very few patients have constitutional symptoms v) Suppuration with or without abscess formation although confirms the diagnosis even then certainty is very essential. Though the evidence of cervical tuberculosis was thought to be decreasing in developing countries the real picture seems to be different. Random survey among the whole population was not done in any country rather hospital based laboratory research was made.

Analysis of arsenic concentrations and correlation in water, soil and aurum by neutron activation analysis technique: a case study in Bagerhat, Bangladesh

Arsenic concentrations were measured in water, soil and arum (vegetables) samples using the Neutron Activation Analysis method and a correlation between arsenic concentrations in the samples was investigated. The case study at Bagerhat, Bangladesh revealed that almost all the water samples were contaminated by a hazardous level of arsenic that exceeding the World Health Organization recommended value of 0.05 mg/L for Bangladesh. Arsenic concentration of all the water samples ranged from 0.09 to 0.87 mg/L. The concentrations in soil and aurum samples were found to be in the range of 2.22-35.21 and 0.07-0.73 mg/kg, respectively. A positive correlation between arsenic concentrations in soil and water samples was observed. Aurum sample was found to be contaminated by arsenic to a harmful level if the corresponding water sample was also highly contaminated.

252 FUNCTIONAL CHARACTERIZATION OF miR-130 FAMILY DURING BOVINE PRE-IMPLANTATION EMBRYO DEVELOPMENT

Small noncoding RNA are known to play a regulatory role in various biological processes including development. Here we aimed to investigate the spatiotemporal expression pattern of the miR-130 microRNA family (miR-130a, miR-130b, and miR-301b) throughout the bovine pre-implantation- stage embryos and to experimentally validate the target of miR-130b. For this, triplicate pools of in vitro-produced immature or mature oocytes (n = 100), zygote (n = 100), 2-cell (n = 50), 4-cell (n = 30), 8-cell (n = 30), morula (n = 20), and blastocyst (n = 20) stage embryos were used to profile the 3 miRNA and one of the predicted target gene MSK1 using SYBR green-based real-time PCR system. Furthermore, based on its expression profile result, miR-130b was selected for localization in all stages of embryos using 3′digoxigenin labeled, LNA-modified oligonucleotide probes. Reporter assay was conducted in cultured bovine cumulus cells to validate the target of miR-130b. The predicted MSK1 gene 3′ untranslated region- containing dual-luciferase miRNA target expression vector (pmirGLO; 600 ng), having renilla luciferase as a control reporter (Promega, Madison, WI, USA), was cotransfected with miR-130b precursor (20 pmol) and/or miR-130b inhibitor (20 pmol) using Lipofectamine 2000 (Invitrogen, Carlsbad, CA, USA) in Opti-MEM1 Medium with 4 independent transfections. Cells were lysed 48 h post-transfection, and luciferase assay was performed in luminometer. Normalization of firefly luciferase activity was based on renilla luciferase activity, and data were presented as mean ± SD. The expression profiling result shows that miR-130b was abundant (>8 to 12-fold) at morula and blastocyst stages. This was further validated by in situ localization, where high fluorescent intensity was seen in the same stages. Greater abundance of miR-301b was evident immediately after fertilization at zygote stage, whereas miR-130a was abundant in equal amount from oocyte until 8-cell stage, after which expression reduced at morula and blastocyst stages. Verification of MSK1 as target of miR-130b using MSK1-pmirGLO-vector showed a significant reduction (>45%) in expression of luciferase when cells were cotransfected with miR-130b precursor compared with cotransfection with miR-130b inhibitor (95%) or only MSK1 construct transfection (100%). MSK1, which was validated as target of miR-130b in the current study for the first time, is known to regulate the phosphorylation of CREB and ATF1 and is required for inhibits of Wnt-fi-catenin pathway and cell proliferation in colon cancer cells (Morán OP et al. 2008 J. Cell Biol. 183(4), 697-710). The results from this study evidenced the spatiotemporal expression of members of the miR130 family during bovine embryo development and their potential regulatory mechanism in the expression of developmentally important gene. The overexpression or inhibition of these miRNA in bovine oocytes and embryos might help in fully understanding their specific role in bovine embryogenesis.

254 REGULATORY microRNA IN THE BIDIRECTIONAL COMMUNICATION OF BOVINE OOCYTES AND THE SURROUNDING CUMULUS CELLS

MicroRNA (miRNA) are small molecules (˜22 nucleotide in length) that influence the expression of hundreds of genes for numerous biological processes including development. In this study we aimed to investigate the presence and role of miRNA in the bidirectional communication of oocyte and cumulus cells. For this, triplicate pools each containing 1600 immature and mature oocytes and their corresponding cumulus cells were used for miRNA isolation using miRNeasy® Mini Kit (Qiagen, Hilden, Germany). From each oocyte and cumulus cell group, 50 ng of small RNA was used for reverse transcription using RT2 miRNA First Strand Kit (SABiosciences, Frederick, MD, USA). The resulting small RNA cDNA was used as a template to profile 88 human miRNA related to cell development and differentiation using SYBR green-based real-time PCR system. Data analysis was preformed using the comparative Ct method after normalization using endogenous control RNA (SNORD44, SNORD47, SNORD48, and U6). In addition, miR-205 and miR-210 were used for localization in pre-implantation stages of embryo using 3′digoxigenin labeled, LNA- modified in situ oligonucleotide probes (Exiqon, Vedbaek, Denmark). The result of the PCR array revealed a total of 34 and 49 miRNA to be greatly abundant in immature and mature oocyte, respectively, compared with the corresponding cumulus cells, whereas only 5 and 4 miRNA were enriched in cumulus cells compared with immature and matured oocytes, respectively. Based on expression intensity, 6 oocyte enriched (miR-205, miR-150, miR-96, miR-122, miR-146a, and miR-146b-5p) and 2 cumulus-cell enriched (miR-452 and miR-210) were selected for expression analysis in pre-implantation-stage embryos and in oocyte and cumulus cells matured with or without cumulus and oocyte factors, respectively. All oocyte-specific miRNA were found to be greatly abundant in early stages of embryo development and drop after 4-cells until the blastocyst stage, following a typical maternal transcript profile. Similar results were obtained by localization of miR-205 in pre-implantation-stage embryos, in which signals were greater until the 4-cell stage and reduced thereafter. However, miR-210 and miR-452 showed no defined profile. miR-205, miR-150, miR-122, miR-146a, miR-146b-5p, and miR-452 were found to be abundant at a greater level (P < 0.05) in oocytes matured without cumulus cells compared with those matured in the presence of cumulus cells. The expression of miR-205, miR-150, and miR-122 in cumulus cells was greater in the presence of oocyte cytoplasm during maturation, whereas 16-fold increases in relative abundance of miR-210 were observed in oocyte- optimized cumulus cells. These results evidenced that oocyte and cumulus cells have a distinct set of miRNA, which is dependent on the bidirectional communication of the oocyte and the surrounding cumulus cells. Moreover, maternal miRNA were found to persist until the major genome activation in bovine.

Procedural sedation in children for magnetic resonance imaging--comparison between ketamine diazepam combination with midazolam fentanyl combination

A deeper level of sedation by an anaesthesiologist is requirement for magnetic resonance imaging (MRI) in paediatric populations and sedation of children is different from sedation of adults. The purpose of the study was to compare the efficacy, safety, tolerability and cost effectiveness of ketamine, diazepam combination to midazolam, fentanyl combination for sedation of children during MRI. One hundred twenty children of both sex, age between 1-10 years, American Society of Anesthesiologist (ASA) physical status I and II were distributed into two groups. Group A (n=60) were sedated with 1.5 mg/kg body weight ketamine and 0.1 mg/kg body weight diazepam intravenously. Group B (n=60) were sedated with midazolam 0.05 mg/kg bodyweight and fentanyl 1 microg/kg body weight intravenously. Both groups showed satisfactory sedating condition for MRI. Incidences of side effects of drug regimens during sedation and recovery were recorded in both groups; those were transient and minor inconveniences. Pulse, blood pressure and respiration were within normal range in both groups. Mean procedure time was almost same in both groups and mean recovery time was more in group A than group B and the difference was statistically significant (p<0.05). Every child of both groups was discharged to home. Sedation regimen of group B found 5 times more costly than group A. Both the regimens were found safe and effective for paediatric sedation during MRI but ketamine, diazepam combination found more cost effective which, is a considerable matter in Bangladesh.

Proximal magnetometry in thin films using betaNMR

Low energy ion implantation of hyperpolarized radioactive magnetic resonance probes allows the NMR study of thin film heterostructures by enabling depth-resolved measurements on a nanometer lengthscale. By stopping the probe ions in a layer adjacent to a layer of interest, it is possible to study magnetic fields proximally. Here we show that, in the simplest case of a uniformly magnetized layer, this yields an unperturbed in situ frequency reference. We also discuss demagnetization contributions to measured shifts for this case. With a simple illustrative calculation, we show how a nonuniformly magnetized layer causes a strongly depth-dependent line broadening in an adjacent layer. We then give some experimental examples of resonance line broadening in heterostructures.

Local magnetic properties of a monolayer of Mn12 single molecule magnets

The magnetic properties of a monolayer of Mn12 single molecule magnets grafted onto a silicon (Si) substrate have been investigated using depth-controlled beta-detected nuclear magnetic resonance. A low-energy beam of spin-polarized radioactive 8Li was used to probe the local static magnetic field distribution near the Mn12 monolayer in the Si substrate. The resonance line width varies strongly as a function of implantation depth as a result of the magnetic dipolar fields generated by the Mn12 electronic magnetic moments. The temperature dependence of the line width indicates that the magnetic properties of the Mn12 moments in this low-dimensional configuration differ from bulk Mn12.

Magnetic-field effects on the size of vortices below the surface of NbSe2 detected using low energy beta-NMR

A low energy radioactive beam of polarized 8Li has been used to observe the vortex lattice near the surface of superconducting NbSe2. The inhomogeneous magnetic-field distribution associated with the vortex lattice was measured using depth-resolved beta-detected NMR. Below Tc, one observes the characteristic line shape for a triangular vortex lattice which depends on the magnetic penetration depth and vortex core radius. The size of the vortex core varies strongly with the magnetic field. In particular, in a low field of 10.8 mT, the core radius is much larger than the coherence length. The possible origin of these giant vortices is discussed.

beta-NMR of isolated lithium in nearly ferromagnetic palladium

The temperature dependence of the frequency shift and spin-lattice relaxation rate of isolated, nonmagnetic (8)Li impurities implanted in a nearly ferromagnetic host (Pd) are measured by means of beta-detected nuclear magnetic resonance (beta-NMR). The shift is negative, very large, and increases monotonically with decreasing T in proportion to the bulk susceptibility of Pd for T > T* approximately 100 K. Below T*, an additional shift occurs which we attribute to the response of Pd to the defect. The relaxation rate is much slower than expected for the large shift and is linear with T below T*, showing no sign of additional relaxation mechanisms associated with the defect.

Near-surface structural phase transition of SrTiO3 studied with zero-field beta-detected nuclear spin relaxation and resonance

We demonstrate that zero-field beta-detected nuclear quadrupole resonance and spin relaxation of low energy (8)Li can be used as a sensitive local probe of structural phase transitions near a surface. We find that the transition near the surface of a SrTiO(3) single crystal occurs at T(c) approximately 150K, i.e., approximately 45K higher than T(c)bulk, and that the tetragonal domains formed below T(c) are randomly oriented.

Volatile anesthetic-induced efflux of calcium from IP3-gated stores in clonal (GH3) pituitary cells

BACKGROUND

Many hormones and neurotransmitters produce their effects by stimulating the generation of inositol 1,4,5-trisphosphate (IP3), a chemical second messenger that releases Ca2+ from intracellular stores. Interruption of this pathway is a potential mechanism through which volatile anesthetics might inhibit chemically mediated communication between cells. This study used GH3 cells (a clonal cell line) as a model system in which to characterize the effects of volatile anesthetics on IP3-induced mobilization of Ca2+ from intracellular stores.

METHODS

Intracellular Ca2+ concentration ([Ca2+]i) was continuously monitored in suspensions of GH3 cells at 37 degrees C using the fluorescent Ca2+ indicator Fura-2. Thyrotropin releasing hormone (TRH) was used to discharge IP3-sensitive intracellular Ca2+ stores. The effects of halothane, isoflurane, and octanol on TRH-induced Ca2+ mobilization were assessed as a function of time and anesthetic concentration. To distinguish between anesthetic effects on Ca2+ uptake and Ca2+ release, experiments were performed using thapsigargin (a Ca(2+)-ATPase inhibitor) to inhibit Ca2+ uptake into IP3-sensitive stores.

RESULTS

Halothane increased resting [Ca2+]i and caused a time- and concentration-dependent inhibition of TRH-induced increases in [Ca2+]i (IC50 = 0.6 mM). Thapsigargin, in concentrations that completely inhibit Ca2+ uptake by IP3-sensitive stores, also caused a time-dependent reduction in the [Ca2+]i response to TRH; the time constant of this decay describes the rate of spontaneous leak of Ca2+ from IP3-sensitive stores (tau = 98 +/- 9 s). In the presence of thapsigargin, halothane produced concentration-dependent increases in the rate of leak from IP3-sensitive stores (tau = 74 +/- 12 and 46 +/- 6 s at 0.5 and 1.0 mM halothane, respectively). Isoflurane and octanol also produced concentration-dependent inhibition of the [Ca2+]i response to TRH.

CONCLUSIONS

Halothane causes a concentration-dependent leak of Ca2+ from IP3-sensitive stores, leading to depletion of the stores and inhibition of IP3-induced increases in [Ca2+]i. This effect occurs at clinically relevant concentrations of halothane (as well as isoflurane and octanol) and may be an important mechanism underlying some of the physiologic effects of volatile anesthetics.

Volatile anesthetic effects on inositol trisphosphate-gated intracellular calcium stores in GH3 cells

The experimental results reviewed in this article indicate that clinically relevant concentrations of halothane (and isoflurane and octanol) cause calcium to leak from IP3-gated intracellular calcium stores, resulting in depletion of the stores. Depletion of intracellular Ca2+ stores should attenuate the actions of a variety of hormones and neurotransmitters that use the IP3 pathway to produce their effects, potentially contributing to many volatile anesthetic side effects including bronchodilatation, vasodilatation, and unresponsiveness to vasoconstrictive agents.