Further evidence for the association of distinct amino acid residues with in vitro and in vivo growth of infectious bursal disease virus

A cell-culture-adapted reverse genetics strain of very virulent infectious bursal disease virus (IBDV) of chickens, designated as BD-3tcC, having four amino acid substitutions (Gln253His, Asp279Asn, Ala284Thr and Ser330Arg) in the capsid protein VP2 was tested for its genetic stability during serial passage in chickens and chicken embryo fibroblast (CEF) cell culture. Results of in vitro and in vivo experiments demonstrated that all four introduced mutations in BD-3tcC remained stable during serial passage in CEF cell culture, but during passage in chickens, amino acid residues at position 253 and 284 reverted from histidine to glutamine and threonine to alanine, respectively. In a parallel experiment, the same substitutions also occurred in a conventionally attenuated vaccine strain D-78 on serial passage in chickens. However, no reversion or substitution took place at positions 279 and 330 during in vivo passage of the mutant virus BD-3tcC or vaccine virus D-78. The findings provide conclusive evidence that while IBDV requires histidine and threonine at positions 253 and 284 for cell culture adaptation, glutamine and alanine at these positions are selected preferentially during in vivo replication.

Effectiveness of radioiodine therapy in treatment of hyperthyroidism

The present non randomized clinical trial was conducted in the Center for Nuclear Medicine and Ultrasound, Mymensingh, Bangladesh for duration of one year. Total 30 patients with hyperthyroidism diagnosed by clinical and biochemical profile were included in the study. All patients received radioiodine treatment and regular follow up at 1st month, 3rd month, 6th month & 9th month were done to evaluate clinical and biochemical status and complications. Data were analyzed by computer with SPSS programme using 't' test and chi-square test. In the present study, out of 30 respondents more than three fourth of the respondents (76.6%) were in the age group of 31-50 years followed by less than 30 years are group (16.7%) and rest of respondents were in the age group of more than 50 years (06.7%). Mean±SD and range of age of the respondents were 39.80±10.02 years and 17-65 years respectively. Among the 30 respondents 11(36.7%) were male and 19(63.3%) were female. Male to female ratio was 1:1.73. Out of 30 patients 26(86.7%) presented with goiter and among them 21(80.8%) has diffused goiter and five (19.2%) had nodular goiter. Baseline mean±SD, median, range of serum T₃ level were 5.24±3.62, 4.34, 1.48-14.65nmol/L respectively. Base line mean±SD, median range of serum T₄ level were 192.25±99.17, 201.77, 1.75-336.25nmol/L respectively. Baseline mean±SD, median range of serum TSH level were 6.33±23.93, 0.15-0.07, 130.46nmol/L respectively. In the present study serum T₃, T₄ level among the respondents sharply decrease from baseline to 2nd follow up then gradually decrease from 2nd to 4th follow up. Serum TSH level gradually increases from baseline to 3rd follow up and then gradually decreases from 3rd to 4th follow up. The result showed radioiodine is an effective option for the treatment of thyrotoxicosis.

Correlation between Intracerebral Hemorrhage Score and surgical outcome of spontaneous intracerebral hemorrhage

Spontaneous intracerebral hemorrhage (ICH) comprises 10-15% of all strokes and has a higher risk of morbidity and mortality (40-45%). A simple and widely valid clinical grading scale, the Intracerebral Hemorrhage Score (ICH score) was developed to predict to outcome of spontaneous ICH. The aim of the present study was to assess the relation between the ICH score and the surgical outcome of ICH by Glasgow Outcome Scale (GOS) at the 30th post ictus day in our perspective. This prospective study was done during the period of April 2009 to October 2010 in Department of Neurosurgery, Bangabandhu Sheikh Mujib Medical University (BSMMU), Dhaka. Forty three cases were enrolled by set inclusion and exclusion criteria. Intracerebral Hemorrhage Score was calculated during admission and the surgical outcome of ICH was determined by GOS by face to face or telephone interview using structured questionnaire on their 30th post ictus day. Correlation between the ICH score and the surgical outcome of ICH was done by Pearson’s correlation coefficient test. Value of r was found to be -0.635 which was statistically highly significant (p=.001) and the relation was found to be negative. Higher ICH score had unfavorable outcome. As correlation between the ICH score and the surgical outcome of ICH was found statistically highly significant, it can be used widely as a grading scale in preoperative counseling. The use of ICH score could improve standardization of clinical treatment protocols and clinical research studies in ICH. Bangladesh Med Res Counc Bull 2013; 39: 1-5

Laparoscopic findings of subfertile women attended in a tertiary level care centre

This retrospective study was done in the Obstetrics and Gynaecology Department of Bangladesh Medical College hospital during the period of July 2003 to June 2004 in the women suffering from primary and secondary subfertility, who underwent laparoscopy. The aim of this study was to see the laparoscopic findings of internal genitalia and other pelvic structures in subfertile women. The study group comprises 55 cases of which 67.37% of primary and 32.73% were of secondary subfertility. Both the ovaries were normal looking in 41.81% cases. Endometriosis was present in 5.45% of both the ovaries. Corpus luteum was seen in 20% cases on right ovary and in 27.27% cases on left ovary. Laparoscopy shows normal looking fallopian tube in 65.45% cases in right side and 61.81% cases in the left side. Right sided tubal block was in 5.46% and 9.10 % in the left side. Both the tubes were patent in 81.6% cases.

Haemodynamic and end tidal CO₂ changes during laparoscopic cholecystectomy under general anaesthesia

A prospective observational study was done on 50 patients to investigate the haemodynamic and end tidal CO₂ (EtCO₂) changes in healthy patients without cardiopulmonary pathology during elective laparoscopic cholecystectomy in head up position under standard protocol of general anaesthesia. During surgery, intra abdominal pressure was maintained at 15 mmHg by a CO₂ insufflator and minute ventilation was controlled with a constant tidal volume and fixed respiratory rate. Haemodynamic parameters, EtCO₂, SpO₂ and ECG were recorded before and after induction and positioning of the patients and at 5 minutes interval for the first 30 minutes, then 10 minutes interval for the rest of the period. Highly significant increase (p<0.001) in pulse rate, systolic, diastolic and mean arterial pressure occurred at 30 minutes after insufflations and positioning of the patient. A very highly significant (p<0.001) increase in EtCO₂ from the base line was at 40 minutes after insufflations and positioning of the patients. There was no change in SpO₂ and ECG. This study supports the significant physiological changes in terms of haemodynamic and EtCO₂ during laparoscopic cholecystectomy and recommends the meticulous monitoring of these parameters during the surgery and balance the benefit of laparoscopy against the intra operative risk.

Preparation Of Carboxymethyl Cellulose/Acrylamide Copoly-Mer Hydrogel Using Gamma Radiation And Investigation Of Its Swelling Behavior

Acrylamide (AAm)/carboxymethyl cellulose (CMC) blend hydrogels have been prepared by the application of gamma radiation from C0-60 source at room temperature (27°C). The preparation conditions such as effect of CMC concentration and radiation dose on gel fraction and swelling behaviors were investigated. The maximum value of gel fraction is obtained at 25 kGy radiation dose. The swelling properties were investigated in distilled water, saline solution (NaCl) and buffer medium. The maximum swelling value of hydrogel was obtained at 48 hours in water. The swelling ratio of hydrogel decreased with increase in concentration of NaCl in swelling medium. In buffer, it was found that swelling ratio increased with increase in pH of medium. Journal of Bangladesh Chemical Society, Vol. 25(2), 132-138, 2012 DOI: http://dx.doi.org/10.3329/jbcs.v25i2.15065

Isolation and identification of Newcastle disease viruses from field outbreaks in chickens and pigeons

Eleven dead or sick birds submitted from farms in the year 2010 with a history of sudden death with respiratory and/or diarrhoeal signs were used for isolation and identification of Newcastle disease virus (NDV). All samples were subjected to routine necropsy. Pooled respiratory tissues were inoculated in embryonated chicken eggs and chicken embryo fibroblast (CEF) cell culture. The growth of NDV was confirmed by embryo mortality, cytopathic effects (CPE) in cell culture, haemagglutination (HA) and haemagglutination inhibition (HI) test. The presence of NDV was confirmed by reverse transcriptionpolymerase chain reaction (RT-PCR). At necropsy seven cases were tentatively diagnosed as Newcastle disease (ND). Out of seven ND-suspected samples, four yielded virus in both embryos and cell culture, while one was positive only in embryos, one only in cell culture and one sample was negative in both embryos and cell culture. RT-PCR successfully amplified a 766 bp fragment covering parts of Matrix and Fusion protein genes of NDV from the samples that were positive either in embryos or in cell culture. It is suggested that RT-PCR could be a rapid and sensitive tool for the detection of NDV. DOI: http://dx.doi.org/10.3329/bvet.v29i2.14341 Bangl. vet. 2012. Vol. 29, No. 2, 41-48

Comparison of genes as target for molecular diagnosis of peste des petits ruminants in goats

Peste des petits ruminants (PPR) are an acute viral disease of sheep and goats. Rapid and accurate diagnosis is essential for successful control. Reverse transcriptase polymerase chain reaction (RT-PCR), a molecular diagnostic test based on amplification of the gene target is more sensitive than other tests. The study was to find an efficient primer set and structural gene, which would be more specific and sensitive for detecting PPR virus (PPRV) in field samples. Six primer sets for six structural genes of PPR were used. Primer against NP gene (np3/np4) was specific and sensitive. To ensure efficient amplification and detection of viruses in field samples, more than one set of primers should be used and F and N gene specific primers were the most suitable. DOI: http://dx.doi.org/10.3329/bvet.v29i2.14343 Bangl. vet. 2012. Vol. 29, No. 2, 56-62

Urinary microalbumin as a risk factor for ischaemic stroke

Microalbuminuria (MA), a microvascular irregularity of the blood - urine interface within kidney glomeruli, may reflect the renal sign of global endothelial dysfunction, and has been associated with an elevated risk of serious cardiovascular events including stroke. This case-control study was carried out in the Department of Neurology, Bangabandhu Sheikh Mujib Medical University (BSMMU), Dhaka, Bangladesh, from January 2008 to December 2009. This relationship appears graded with higher levels of microalbuminuria being independently associated with a greater magnitude of vascular risk over time. We studied 60 patients of ischemic stroke with in 4 weeks of onset of symptoms and performed a case control study for MA by spot urinalysis. The incidence of microalbuminuria was 31.7% of the patients compared with 8.3% of the controls. Of all the traditional risk factors for stroke - age, male gender, hypertension, diabetes, dyslipidemia, smoking showed a positive correlation with the presence of MA (p<0.05). The effect of microalbuminuria and subtypes of ischemic stroke was observed that small vessels stroke (lacunar infract) were more (70%) than large vessels stroke (30%) and effect of microalbuminuria 21.67% higher in small vessels stroke than large vessels stroke. The presence of microalbuminuria appears to independently predict proper clinical outcome following acute stroke.

Molecular epidemiology of tuberculosis in rural Matlab, Bangladesh

OBJECTIVE

To characterise and classify clinical isolates collected from tuberculosis (TB) patients in rural Bangladesh and to investigate the mode of transmission.

DESIGN

An epidemiological study using a combination of conventional and molecular methods was performed in a rural population of Bangladesh. A total of 168 clinical isolates were collected from TB patients. Deletion analysis, used for rapid differentiation of members of the Mycobacterium tuberculosis complex, spoligotyping and variable number tandem repeats of mycobacterial interspersed repetitive units (VNTR-MIRU) typing were used.

RESULTS

Deletion analysis identified all isolates as M. tuberculosis and further divided them into 109 strains (65%) carrying the M. tuberculosis deletion region 1 (TbD1-intact or 'ancestral' strains) and 59 strains (35%) lacking this region (TbD1 or 'modern' strains). MIRU analyses showed that 149 strains (89%) had unique patterns, whereas 19 strains (11%) clustered into eight groups. The largest cluster comprised five TbD1 strains of the Beijing type. The rate of recent transmission was estimated to be 6.5%.

CONCLUSIONS

Our results suggest that TB in rural Bangladesh is caused primarily by reactivation of latent infections involving TbD1 intact strains, overlaid with the recent emergence of Beijing strain clusters that include multidrug-resistant isolates.

Distribution of prosaposin mRNA in the central nervous system of the pigeon (Columba livia)

Bioassay and immunohistochemical studies have detected the presence of prosaposin in the central nervous system (CNS) of mammals. Here, first time, we have determined the partial cDNA sequence of pigeon prosaposin and mapped the distribution of its mRNA in the pigeon CNS. The predicted amino acid sequence of pigeon prosaposin showed 93 and 60% identity to chicken and human prosaposin, respectively. In situ hybridization, autoradiograms showed that the prosaposin mRNA expression was found in the olfactory bulb, prepiriform cortex, Wulst, mesopallium, nidopallium, hippocampal formation, thalamus, tuberis nucleus, pre-tectal nucleus, nucleus mesencephalicus lateralis, pars dorsalis, nucleus isthmi, pars parvocellularis and magnocellularis, Edinger-Westphal nucleus, optic tectum, cerebellar cortex and nuclei, vestibular nuclei and gray matter of the spinal cord. These results suggest that the cDNA sequence of pigeon prosaposin is comparable to other vertebrates, and the general distribution pattern of prosaposin mRNA resembles those are found in mammals.

Antioxidant and hepatoprotective activity of an ethanol extract of Syzygium jambos (L.) leaves

Herbal medicines have traditionally been used worldwide for the prevention and treatment of liver disease with fewer adverse effects. The leaves of the Syzygium jambos (SJL) plant were chosen and studied for their antioxidant activity in vitro and hepatoprotective activity in vivo. The antioxidant activity of the ethanol extract was examined in vitro using a 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging assay, reducing capacity, total phenol, total flavonoid content, and total antioxidant capacity. The extract had significant dose-dependent antioxidant activity in all in vitro experiments. IC(50) values of SJL and ascorbic acid (standard) were found to be 14.10 and 4.87 μg/mL, respectively, according to a DPPH radical scavenging assay. Hepatoprotective activity of the plant extract was evaluated in a rat model of carbon tetrachloride (CCl(4))-induced liver damage. CCl(4) significantly altered serum marker enzymes, total bilirubin, total protein, and liver weight. The extract caused these values to return to normal in rats with CCl(4)-induced liver damage that were given SJL. This indicated the hepatoprotective potential of SJL and was comparable to use of the standard drug silymarin. Thus, the present study revealed that SJL may have antioxidant and hepatoprotective activity.

Predictive value of urine cultures in evaluation of bacterial colonization of ureteral stents

To evaluate the predictive value of urine cultures in the assessment of ureteral stent colonization and to investigate the frequency of double J stent colonization and stent associated bacteriuria. This observational study was conducted in the department of Urology, Dhaka Medical College Hospital from December 2006 to March 2009. A total of 100 patients (mean age 39.2 ± 9.9 years, range 18-60 years, 69 male and 31 female) needing internal ureteral stent placement for different sorts of urinary tract operations were included in the study. Sterile urine samples were obtained from each patient before stenting and all patients had been given short-term prophylactic antibiotic (5-12 days). On the day of stent removal midstream urine were obtained from all patients for microbiological culture. Stents removed by aseptic precaution. Proximal and distal tip segments (3-5 cm) were also sent for culture. The lowest and highest durations of stenting were 10 and 86 days respectively (median 35 days). Both bacteriuria and bacterial colonization was significantly higher as duration of stenting increases (p=0.045 and p<0.001). E. coli was the most common microorganism isolated from both urine and stent culture. However, colonization rate of stents was much higher (45%) than positive urine cultures (21%) indicating that urine culture is less sensitive to diagnose stent colonization (k-value = 0.49). The study concludes that bacterial colonization significantly increases with indwelling time of stent and sterile culture of urine does not rule out that the stent itself is colonized.

Pattern of chronic suppurative otitis media

This observational study was conducted to know the bacteriological pattern of chronic suppurative otitis media. For this 110 patients of Chronic Suppurative Otitis Media (CSOM) were selected from January 2006 to December 2007 at the out patient department of Otolaryngology and Head Neck surgery, BSMMU and Dhaka Medical College Hospital, Dhaka. Among the 110 patients unilateral involvement was 76.36% and bilateral involvement was 23.64%. Ninety percent patients presented with tubotympanic variety and 10% patients presented with attico-antral variety. Bacteriologically pure growth was found in 79.09% cases, mixed growth in 10.91% cases, no growth in 10% cases. Only aerobic bacteria were isolated in the present series. Pseudomonas aeruginosa was the most common organism (43.68%) isolated in pure culture followed by staphylococcus aureus 27.59%, E. coli 10.35%, Kleibsiella spp. 9.19%, proteus spp. 8.04%. Amikacin was the most effective antibiotic followed by Gentamycin, Ciprofloxacin, Ceftazidime, Cetriaxone. Before giving therapy bacterial growth and sensitivity pattern is to be known where facilities are available.

Renewable Energy: The Key to Achieving Sustainable Development of Rural Bangladesh

Renewable energy technologies (RETs) can help reduce poverty, energy shortage and environmental degradation such as desertification, biodiversity depletion and climate change effects in Bangladesh. The country is short of gas and electricity supply. Over-exploitation of biomass in meeting energy needs of the rural people has caused environmental degradation. RET can help solve those problems if it is widely used in the rural Bangladesh where people primarily depend on biomass energy. Bangladesh has enough renewable to mitigate such energy crisis and its adverse consequences. Bangladesh being an underdeveloped country, global initiative would be helpful in transferring RETs for the village households. This paper describes the glimpses of RETs in Bangladesh in terms of its policy issues, implementation, dissemination, marketing, and research and development activities. Modern RETs are still in the research, development and demonstration phase in the country. Like most of the developing countries, there is a niche market for new RETs and several private sector entrepreneurs and NGOs have tried to explore this market. DOI: http://dx.doi.org/10.3329/jce.v26i1.10175 JCE 2011; 26(1): 9-15

Outcome of metformin treatment in polycystic ovary syndrome

The polycystic ovary syndrome (PCOS) is a clinical diagnosis. During one year period, 50 women suffering from PCOS were treated with either 850 mg/twice daily or 500 mg/thrice daily along with clomiphene citrate and/or letrozole, with advice for exercise and dietary therapy. Diagnosis of the PCOS patients was made by the presence of two out of the following three criteria: (a) oligo and/or anovulation, (b) hyperandrogenism (clinical and/or biochemical), and (c) polycystic ovaries, with the exclusion of other aetiologies. The mean±SD age of our patients was 26.74±3.85 years, BMI 26.64±2.64 kg/m2, pulse 80.56±4.61 b/min, systolic blood pressure 113.80±4.40 mmHg and diastolic blood pressure 76.10±4.77 mmHg, duration of marriage 6.19±3.20 years, and parity was 43(86%) nulliparous and 7(14%) primiparous. Oligomenorrhoea was present in 100%, hypomenorrhoea in 38%, secondary amenorrhoea in 28% and acne in 70% women. Results showed that 92% women followed advice on exercise and dietary therapy, in maximum number of women progesterone level was 31.40 nmol/L (66%), weight loss was 2 kg (44%), menstrual cycle regular (90%) and pregnancy test negative (90%). Only in 5 cases (10%) pregnancy test was positive.

New introduction of clade 2.3.2.1 avian influenza virus (H5N1) into Bangladesh

Since the first outbreak of highly pathogenic H5N1 avian inafluenza (HPAI) in Bangladesh in February 2007, a total of 519 disease events have been reported till 22 October 2011. Partial HA gene sequences of 11 selected H5N1 HPAI isolates of 2007 to 2011 were determined and subjected to phylogenetic analysis. The study revealed a recent introduction of clade 2.3.2 and 2.3.4 viruses into Bangladesh in 2011 in addition to clade 2.2 viruses that had been in circulation since 2007. Clade 2.3.2 virus isolates from Bangladesh are phylogenetically related to the newly designated clade 2.3.2.1 viruses, reported recently from Asia and Eastern Europe.

Haemolysin E- and enterohaemolysin-derived haemolytic activity of O55/O157 strains and other Escherichia coli lineages

Among three haemolysins identified thus far in Escherichia coli, alpha-haemolysin (HlyA) is encoded on the pathogenicity islands of extraintestinal pathogenic strains, while enterohaemolysin (EhxA) is encoded on the virulence plasmids of enterohaemorrhagic E. coli (EHEC) strains. In contrast, the gene for haemolysin E (HlyE) is located on the E. coli chromosome backbone and is therefore widely distributed among E. coli strains. However, because hlyE gene expression is repressed by the H-NS protein and because the gene has been disrupted in many strains, its haemolytic activity cannot be detected in wild-type strains by routine screening on blood agar plates. In this study, we found that the HlyE-derived haemolytic activity of enteropathogenic E. coli (EPEC) O55 : H7 can be detected after anaerobic cultivation on a washed blood agar plate (EHX plate) that is used to detect the production of EhxA. We also found that the haemolytic activity of EHEC O157 : H7 observed on EHX plates under aerobic and anaerobic growth conditions is derived from EhxA and HlyE, respectively; this differential expression of the two haemolysins occurs at the transcriptional level. Our analysis of 60 E. coli strains of various pathotypes and phylogenies for their repertoires of haemolysin genes, haemolytic phenotypes and hlyE gene sequences revealed that HlyE activity can generally be detected on EHX plates under anaerobic growth conditions if the gene is intact. Furthermore, our results indicate that hlyE gene inactivation occurred in three of the five E. coli lineages (phylogroups A, B1 and B2), which demonstrates phylogroup-specific gene disruption patterns.

A sensitive and simple plaque formation method for the Stx2 phage of Escherichia coli O157:H7, which does not form plaques in the standard plating procedure

Bacteriophages are fascinating genetic elements that play key roles in the evolution and diversification of bacterial genomes. Shiga toxin (Stx)-transducing phages are important genetic elements that disseminate the stx genes among enterohemorrhagic Escherichia coli (EHEC). They are generally regarded as lambda-like phages, but their biological and genetic properties have not been fully elucidated. This is partly due to a serious obstacle in obtaining visible plaques. Here, we describe a modified double agar overlay method that allows us to easily detect and accurately enumerate plaques of Sp5, the Stx2 phage of the EHEC O157 Sakai strain, which otherwise does not produce plaques in the standard plating procedure. In the modified method, the top agar was supplemented with mitomycin C (MMC) and Ca(2+) (or Mg(2+)). MMC appears to prevent the lysogenization of Sp5 and/or compel Sp5 to follow the lytic cycle by inducing the SOS response in the host cells. The divalent cations significantly improve phage adsorption to the host cells and thus yield a synergistic effect in combination with MMC. We further applied this method to a receptor analysis of Sp5 and obtained findings that suggest that the YaeT (BamA) protein serves as the receptor of Sp5. This method would be a very useful tool in studies of Stx2 phages and studies of other phages from various bacteria, in which researchers often encounter problems with plaque formation.

Comparative study between combination of famciclovir and prednisolone with prednisolone alone in acute Bell's palsy

The antiviral drug acyclovir or its analogue, valacyclovir, has been applied in various trials on Bell's palsy with inconsistent results. We compared the therapeutic effect of famciclovir plus prednisolone with prednisolone alone, in patients with Bell's palsy. In a randomized, prospective trial, 68 patients were randomized to treatment with famciclovir and prednisolone (34 patients) or prednisolone alone (34 patients). All patients underwent supportive therapy. Severity of Bell's palsy was evaluated using the House-Brackmann scale (HBS). Follow-up was done after 1 week, 1 month and 3 months, with complete recovery defined as House-Brackmann grade I. The analysis revealed that recovery rates at month 1 and 3 were significantly higher in combination group than that of prednisolone only group (94.1% vs. 61.8% and 97.1% vs. 74.5% respectively). Again recovery from mild to moderate (HBS-II, III, IV) Bell's palsy occurred completely at month 3 and that of severe (HBS-V, VI) Bell's palsy was two-third of the patients. Again in severe Bell's palsy combination treatment increased the chance of complete recovery more than 10-fold than that of steroid only. The study results suggest that better outcome for Bell's palsy patients occurred if they were treated with prednisolone and famciclovir combination instead of prednisolone alone. In fact a considerable number of patients were benefited from additional antiviral therapy with famciclovir.

Different doses of atropine on heart rate fluctuations during reversal of neuromuscular blockade

It was a prospective comparative clinical study carried out in the Department of Anaesthesia, Combined Military Hospital (CMH), Dhaka, to evaluate the heart rate changes during reversal of neuromuscular blockade by using 3 different doses of atropine (in a mixture with neostigmine) and thereby detect comparatively safer dose. Sixty patients of ASA (American Society of Anesthesiologists) grade I and II physical status were divided equally into 3 groups. Neostigmine 0.05 mg/kg body weight mixed with atropine 0.02, 0.015 and 0.01 mg/kg body weight given intravenously in group A, B and C respectively during reversal. The 3 groups were compared in age, sex, body weight, and ASA grades, but there was no significant difference (p>0.05) between 3 groups. It is revealed that in Group C (atropine at a dose of 0.01 mg/kg with neostigmine), heart rate affected very little but salivary and tracheobronchial secretions were more. One of them had laryngospasm which was managed conservatively. In Group B (who received atropine 0.015 mg/kg) incidence of tachycardia observed was less than Group A (who received atropine 0.02 mg/kg). The patients of this group also had some salivary secretions but less than group C. Tachycardia was most marked in Group A but had minimum salivary secretions. Statistical analysis of heart rate changes in different times among the 3 Groups was significant (p<0.05). It was highly significant (p<0.01) in 1 minute after reversal. So relatively lower dose (0.015 mg/kg) of atropine with neostigmine than the conventional dose (0.02mg/kg) can be used to decrease tachycardia during reversal of neuromuscular blockade especially in haemodynamically unstable patients.

Feasibility study for thermal treatment of solid tire wastes in Bangladesh by using pyrolysis technology

In this study on the basis of lab data and available resources in Bangladesh, feasibility study has been carried out for pyrolysis process converting solid tire wastes into pyrolysis oils, solid char and gases. The process considered for detailed analysis was fixed-bed fire-tube heating pyrolysis reactor system. The comparative techno-economic assessment was carried out in US$ for three different sizes plants: medium commercial scale (144 tons/day), small commercial scale (36 tons/day), pilot scale (3.6 tons/day). The assessment showed that medium commercial scale plant was economically feasible, with the lowest unit production cost than small commercial and pilot scale plants for the production of crude pyrolysis oil that could be used as boiler fuel oil and for the production of upgraded liquid-products.

Evaluation of risk factors of oral cancer

This cross sectional study was done for the evaluation of the risk factors of oral cancer. This study was carried out in the department of Otolaryngology-Head & Neck Surgery of Bangabandhu Sheikh Mujib Medical University and Dhaka Medical College Hospital, Dhaka, Bangladesh. A total of 90 consecutive patients with oral squamous cell carcinoma (OSCC) were studied in Otolaryngology department of BSMMU and DMCH from January 2003 to December 2005. A questionnaire was used for data collection from careful history taking, clinical examination and investigations. About 71.1% were habituated with betel quid chewing, 36.7% were habituated with smoking but among 23.3 % also betel quid chewer in addition. None of the patient was found to be habituated with alcohol consumption. Majority of the patients of OSCC were malnourished, of which female were more in number, and it was found that nutritional status was significantly associated with sex. Odds ratio (OD) showed that malnutrition was positively associated with female subjects. Also it was found that 69.01% betel quid chewer was malnourished and nutritional status was significantly associated with chewing and smoking habit. Betel quid chewing, smoking and malnutrition is important risk factor of oral cancer.

Preoperative use of granisetron plus dexamethasone and granisetron alone in prevention of post operative nausea and vomiting in tonsillectomy

This prospective study was done for to see the efficacy of preoperative use of granisetron plus dexamethasone (Group A) & granisetron (Group B) alone for the postoperative prevention of nausea & vomiting after tonsillectomy operation. One hundred patients undergoing tonsillectomy & adenoidectomy operation under general anaesthesia who were admitted in the Mymensingh Medical College Hospital during the period from July 2008 to June 2009 with American Society of Anaesthesiologists (ASA) grade I & II with age 3-40 years, body weight 10-60 kgs, were studied. Observation of this study was analyzed in the light of comparison between the two groups. All results were expressed as mean±SEM. Age in Group A 15.98±1.028 & Group B 17.18±0.961 years; Weight in Group A 38.40±1.492 & Group B 39.76±1.561 kgs and operational duration in Group A 52.60±0.786 & Group B 52.70±0.823 minutes. The studied groups were statistically matched for age, weight, duration of surgery. We observed that the effects of combination of granisetron & dexamthasone are more than granisetron alone in prevention of nausea & vomiting after tonsillectomy operation. The frequency of vomiting was 4% in combination & 16% in single therapy which is statically significant (p<0.05).

Determinants of antenatal and postnatal care visits among Indigenous people in Bangladesh: a study of the Mru community

INTRODUCTION

Antenatal and postnatal care services are significant interventions to improve maternal health and prevent maternal and infant deaths. However, these services are poorly developed in Bangladesh, particularly among Indigenous women. This study examined factors associated with antenatal and postnatal care visits among the Mru, the most underprivileged Indigenous people in Bangladesh.

METHODS

This cross-sectional study used both quantitative and qualitative methods. In total, 374 currently married Mru women with at least one child aged 5 years or younger were selected from 3 upazilas (sub-districts) of Bandarban District, Bangladesh for survey. In addition, in-depth interviews were performed with 26 Mru leaders, Mru women, traditional midwives, village 'doctors', school teachers, health and non-government organization workers. Associations between antenatal and postnatal care visits and the women's backgrounds characteristics were assessed by bivariate and multivariate analyses.

RESULTS

The traditional Mru prenatal and postnatal practices potentially inhibited women from seeking care. Both antenatal (11.2%) and postnatal (6.4%) care visits among the Mru women were lower than the national level. Most visits were to traditional midwives in their rural villages, rather than to health complexes or hospitals. The main reasons for lack of antenatal and postnatal care were travelling distance to care and transportation problems. Multivariate analysis revealed factors associated with antenatal care were the respondent's place of residence, age, level of education, distance to the service centers and exposure to any mass media. Similar results were obtained with regard to postnatal care visits.

CONCLUSIONS

This study suggests that cultural issues, distance, infrastructure and socioeconomic status are important determinants of maternal healthcare-seeking behavior. Healthcare delivery systems and appropriate education programs should be developed at the village level to improve the health of mothers and children in the Mru community.

Comparison between tramadol hydrochloride & nalbuphine hydrochloride in the treatment of per-operative shivering after spinal anaesthesia

Per-operative shivering following spinal anaesthesia is a common problem in the operation theatre. Adequate management of shivering during operation is one of the goals of anesthesiologists for the benefit of the patient. Because there are many unpleasant and harmful effects caused by shivering in many patients especially respiratory and cardiac disease patients. For this reason aggressive and optimal treatment of per-operative shivering is essential to reduce the morbidity of the patients. Our observations were that occurrence of shivering was more in younger patients than older patients, thin patients than obese patients, anxious patients than non-anxious patients and more frequent in patients who received vasoconstrictor drugs, administration of fluid at running rate just before or during operation, administration of cold local anaesthetic agents (by taking drug from the freeze) into subarachnoid space. And shivering was better managed by administration of nalbuphine HCl and surface skin warming (wrapping of the skin). There are many studies regarding the incidence, prevention & treatment of post-operative shivering but there is no study regarding the incidence & treatment of per-operative shivering by nalbuphine following spinal anaesthesia. This study was designed to compare the anti-shivering efficacy and side effects (Nausea, Vomiting, and Somnolence) of tramadol hydrochloride with that of nalbuphine hydrochloride in the treatment of per-operative shivering following spinal anaesthesia. This study was also done to observe the incidence of shivering during operation following spinal anesthesia.

Role of magnesium sulphate in the treatment of hypomagnesaemia in eclamptic patients

Hypomagnasaemia has been identified as one of the main causes of eclampsia and preeclampsia which causes maternal and fetal/neonatal morbidity and mortality. In spite of wide difference of opinion about the best anticonvulsant, magnesium sulphate, diazepam and phenytoin are currently the mostly widely used anticonvulsants. The present study tried to find out the role of MgSO4 in correcting hypomagnasaemia in eclamptic women in Bangladesh. The study included 60 healthy (non eclamptic) 60 eclamptic women and was carried out in two hospitals of Dhaka city, during January 1999 to June 2000. Required tests were done in the Department of Biochemistry, BSMMU. Comparison of pretreatment clinical parameters between the two study groups showed highly significant (p<0.001) differences, MgSO4 level, pulse rate, systolic and diastolic blood pressure, and respiratory rate. After the case group of women was treated with MgSO4, the clinical parameters, pulse rate, systolic and diastolic blood pressure, and respiratory rate, between control and case groups showed no significant differences. However, serum magnesium level in case group increased to 3.41±0.21 mg/dl from pretreatment level of 1.02±0.26 mg/dl, and when compared to control (2.25±0.26 mg/dl), the increase was highly significant (p<0.001). It may be concluded that correction of hypomagnesemia may help to improve eclamptic situation.

Male sub-fertile patients in a tertiary hospital

Estimated prevalence of subfertility is 10% of couples; 35 40% male, 40 50% female and remainder involve both sexes. We analyzed semen of 50 sub-fertile male subjects attending infertility unit outpatient department, Department of Obstetrics and Gynaecology, Bangabandhu Sheikh Mujib Medical University, between July 2007 and December 2008, to establish cause of their problem and initiate treatment regimen to correct their problem. Mean age was 32.68 years, known medical disorders was present in 6(6% history of mumps, 4% history of orchitis, 2% diabetes), 28% were smokers, and none was drug addict. Semen analysis: mean±SD semen volume 1.94±1.08 ml, concentration 19.43±25.18 106/ml, motility 24.04±26.49%, rapid linearity 13.10±15.74%, slow linearity 8.16±8.65%, non-progressive 2.74±6.23%, immotile 33.68±33.06%, morphology 21.62±26.15%, head abnormality 21.06±24.72%, midpiece abnormality 14.04±17.12%, and tail and other abnormalities 10.90±17.28%. Agglutination was seen in 2%. Diagnosis was 42% azoospermia, 4% normozoospermia, 12% oligoasthenozoospermia, 10% asthenozoospermia, 18% oligozoospermia, 10% oligozoospermia with reduced motility, 2% each oligozoospermia with infection and astheno and teratozoospermia.

POEMS Syndrome

A 49 years old male patient admitted with 2 years history of lower extremity symmetrical sensorimotor polyneuropathy, sclerodermic skin change, erectile dysfunction, hepatosplenomegaly and monoclonal gammopathy. The clinical evaluation met the criteria for the diagnosis of (polyneuropathy, organomegaly, endocrinopathy, monoclonal gammopathy, skin changes) POEMS syndrome. The patient was treated with corticosteroid and melphelan and responded well. We present a case different from the other cases with severe unusual burning sensation all over the body, which was his sole complaint and with this complaint he visited lot of doctors including psychiatrist.

Low emittance, high brilliance relativistic electron beams from a laser-plasma accelerator

Progress in laser wakefield accelerators indicates their suitability as a driver of compact free-electron lasers (FELs). High brightness is defined by the normalized transverse emittance, which should be less than 1π mm mrad for an x-ray FEL. We report high-resolution measurements of the emittance of 125 MeV, monoenergetic beams from a wakefield accelerator. An emittance as low as 1.1±0.1π mm mrad is measured using a pepper-pot mask. This sets an upper limit on the emittance, which is comparable with conventional linear accelerators. A peak transverse brightness of 5×10¹⁵ A m⁻¹ rad⁻¹ makes it suitable for compact XUV FELs.

Spatial variability of arsenic concentration in soils and plants, and its relationship with iron, manganese and phosphorus

Spatial distribution of arsenic (As) concentrations of irrigation water, soil and plant (rice) in a shallow tube-well (STW) command area (8 ha), and their relationship with Fe, Mn and P were studied. Arsenic concentrations of water in the 110 m long irrigation channel clearly decreased with distance from the STW point, the range being 68-136 microg L(-1). Such decreasing trend was also noticed with Fe and P concentrations, but the trend for Mn concentrations was not remarkable. Concerning soil As, the concentration showed a decreasing tendency with distance from the pump. The NH(4)-oxalate extractable As contributed 36% of total As and this amount of As was associated with poorly crystalline Fe-oxides. Furthermore only 22% of total As was phosphate extractable so that most of the As was tightly retained by soil constituents and was not readily exchangeable by phosphate. Soil As (both total and extractable As) was significantly and positively correlated with rice grain As (0.296+/-0.063 microg g(-1), n=56). Next to drinking water, rice could be a potential source of As exposure of the people living in the As affected areas of Bangladesh.

Detection of duck plague virus antigen in tissues by immunoperoxidase staining

An avidin-biotin-peroxidase method of immunoperoxidase staining was successfully adapted for detection of duck plague virus antigen in formalin-fixed, paraffin-embedded tissue sections of the liver and spleen of experimentally infected domestic ducks. Positive staining was localized mostly in the nucleus but was also present in the cytoplasm of a few hepatocytes and von Kupffer cells of the liver, and lymphocytes and reticular cells of the spleen.

Early pathogenesis of experimental reovirus infection in chickens

One-day-old specific-pathogen-free, light hybrid chickens were infected orally with an avian arthrotropic reovirus and examined at intervals from 2 h until 12 days after infection. Entry, primary replication and spread of virus were studied by infectivity assay, immunohistochemical study and electron microscopy in a wide range of tissues. These showed viral entry and primary replication in the epithelium of intestine and bursa of Fabricius within 12 h after oral infection. These were followed by a rapid and pantropic distribution of virus which reached most tissues within 24 to 48 h after infection.

The effect of selenium and vitamin E on the lymphocytes and immunoglobulin-containing plasma cells in the lymphoid organ and mucosa-associated lymphatic tissues of broiler chickens

The present research has been designed to understand the effect of selenium and vitamin E on the lymphocyte and changes in the frequency of Ig-containing plasma cells in the lymphatic organ and ileum (representative organ for mucosa-associated lymphatic tissues) of different postnatal stages of Kasilla broiler chickens. A routine haematoxylin and eosin (H and E) stain were used to study the histology of the lymphocytic changes, and indirect immunoperoxidase staining method was performed for the study of the distributional and dynamical changes of the Ig-containing plasma cells within the lymphatic tissues and in the ileum of control broilers and in the broilers supplemented with different concentration of selenium and vitamin E in the diet. Histologically, the population of lymphocytes decreased in the lobules of the thymus, medulla of bursal follicles, splenic masses, lymphatic nodules of the cecal tonsil, and villi of the ilium in 0.1 mg and 0.5 mg selenium supplemented broilers in comparison with the control. The population of these cells was found to increase in 150 mg and 300 mg vitamin E supplemented chickens in the present study. In the spleen IgG- and the IgM-containing plasma cells were more than IgA-containing plasma cells. In contrast, in the cecal tonsil and ileum IgA-containing plasma cells were more than IgG- and IgM-containing plasma cells. The frequency of these immunopositive cells were decreased in 0.1 mg and 0.5 mg selenium supplementated chickens, and increased their frequency in the chickens supplemented with 150 mg and 300 mg vitamin E. In the spleen the frequency of IgM-containing plasma cells and both in the cecal tonsil and ileum, the IgG-containing plasma cells were more decreased by selenium supplementation which restored in their population by vitamin E supplementation.

Qualitative and quantitative analysis of goat ovaries, follicles and oocytes in view of in vitro production of embryos

Goat ovaries were collected from the slaughterhouse and categorized as right, left, corpus luteum (CL)-present and -absent group and evaluated on the basis of weight (g), length (cm), width (cm), number of follicles, follicles aspirated and number and state of cumulus-oocyte-complexes (COCs). Comparatively higher weight [(0.66+/-0.02) vs (0.64+/-0.02) g], length [(1.17+/-0.02) vs (1.11+/-0.02) cm] and width [(0.77+/-0.02) vs (0.74+/-0.02) cm] were found in right ovaries than those of left. On the other hand significantly (P<0.05) higher weight [(0.71+/-0.03) vs (0.64+/-0.01) g] and width [(0.76+/-0.03) vs (0.75+/-0.01) cm] were found in CL-present group than those of CL-absent group of ovaries. The left ovaries contained comparatively higher number of normal COCs [(1.06+/-0.09) per ovary] than right ovaries [(1.03+/-0.10) per ovary] and the similar trend was found in total number of follicles [(4.51+/-0.25) vs (4.30+/-0.23) per ovary] and follicles aspirated [(2.55+/-0.14) vs (2.52+/-0.12) per ovary]. But the total COCs per ovary was almost similar in both ovaries [right and left: (1.85+/-0.12) and (1.85+/-0.11) per ovary, respectively]. Higher number of total COCs [(1.87+/-0.09) vs (1.76+/-0.16) per ovary], total number of follicles [(4.45+/-0.19) vs (4.16+/-0.37) per ovary], follicles aspirated [(2.55+/-0.10) vs (2.48+/-0.21) per ovary] and normal COCs [(1.12+/-0.07) vs (0.76+/-0.14) per ovary] were found in CL-absent group than those of CL-present group of ovaries.

Immunoglobulin (Ig)-containing plasma cells in the Harderian gland in broiler and native chickens of Bangladesh

The distribution and frequency of immunoglobulin (Ig)-containing plasma cells, their variations due to sex, and the mode of secretion of Ig cells into the duct system of the Harderian gland was investigated in broiler and native chickens of both sexes in Bangladesh. The Harderian gland is covered by a capsule, and the connective tissue septa divide the gland into numerous unequal-sized numerous lobes and lobules. The Ig-containing plasma cells were located in the interstitial space, interacinar space, apical part of the lobule, and lumina of the lobules of the Harderian gland in both broiler and native chickens. The population of these Ig-containing plasma cells varied in between broiler and native chickens, and also between male and female broiler and native chickens. In the broiler, the number of IgM-containing plasma cells was higher; in contrast, in the native chickens, the population of IgA-containing plasma cells was larger. In the broiler, there were more IgA- and IgG-containing plasma cells in the male; in contrast, there were more IgM-containing plasma cells in female. In native chickens the frequency of IgA-containing plasma cells was greater in the female than male. When the data for broiler and native birds were compared, it was found that there were significantly more IgA- and IgG-containing plasma cells in the native male and female chickens than in the broiler males and females. The secretory Igs were located in the lumina of acini and the duct system of the Harderian gland. In the present study Ig-containing plasma cells were observed to be released in the lumina of the lobules of Harderian gland by the breakdown of acinar tissues in broilers, and by holocrine mode of secretion in the native chicken. These results suggested that the Harderian gland, even though it is not a lymphoid organ as a whole, but acts as an immunopotent organ in chickens, and that the gland in native chicken contains more Ig-containing plasma cells due to their scavenging.

Increase in rice grain arsenic for regions of Bangladesh irrigating paddies with elevated arsenic in groundwaters

Concern has been raised by Bangladeshi and international scientists about elevated levels of arsenic in Bengali food, particularly in rice grain. This is the first inclusive food market-basket survey from Bangladesh, which addresses the speciation and concentration of arsenic in rice, vegetables, pulses, and spices. Three hundred thirty aman and boro rice, 94 vegetables, and 50 pulse and spice samples were analyzed for total arsenic, using inductivity coupled plasma mass spectrometry (ICP-MS). The districts with the highest mean arsenic rice grain levels were all from southwestern Bangladesh: Faridpur (boro) 0.51 > Satkhira (boro) 0.38 > Satkhira (aman) 0.36 > Chuadanga (boro) 0.32 > Meherpur (boro) 0.29 microg As g(-1). The vast majority of food ingested arsenic in Bangladesh diets was found to be inorganic; with the predominant species detected in Bangladesh rice being arsenite (AsIII) or arsenate (AsV) with dimethyl arsinic acid (DMAV) being a minor component. Vegetables, pulses, and spices are less important to total arsenic intake than water and rice. Predicted inorganic arsenic intake from rice is modeled with the equivalent intake from drinking water for a typical Bangladesh diet. Daily consumption of rice with a total arsenic level of 0.08 microg As g(-1) would be equivalent to a drinking water arsenic level of 10 microg L(-1).

Reversion of molecularly engineered, partially attenuated, very virulent infectious bursal disease virus during infection of commercial chickens

A molecularly cloned, tissue culture-adapted infectious bursal disease virus (BD-3tc) was generated from a very virulent strain by the reverse genetics approach following site-directed mutagenesis (Q253H and A284T in VP2). The pathogenicity of BD-3tc was tested in commercial chickens. The wild-type strain (BD-3wt) and the molecularly cloned parental strain (BD-3mc) were included for comparison. The subclinical course of the disease, with delayed and milder pathological lesions followed by quick follicular regeneration in the bursa of Fabricius in BD-3tc-inoculated birds, suggested that these amino acid substitutions made BD-3tc partially attenuated. However, severe bursa atrophy was observed at 14 days after inoculation. Reverse transcription-polymerase chain reaction coupled with restriction enzyme analysis revealed that both point mutations in BD-3tc had reverted 14 days after inoculation. Further investigations demonstrated that the codon for amino acid at position 284 had already reverted to the wild-type phenotype (T284A) 3 days after inoculation.

Microwave enhanced recovery of nickel-copper ore: communition and floatability aspects

A study describing the effect of microwave radiation, at a frequency of 2450 MHz, on the processes of communication and flotation of a complex sulphide nickel-copper ore is presented. Ore communication has been investigated under standard radiation-free conditions and after ore treatment in a radiated environment as a function of ore size, exposure time to radiation, and microwave power. The findings show that communication is tremendously improved by microwave radiation with values of the relative work index as low as 23% at a microwave power of 1.406 kW and after 10 s of exposure time. Communication is affected by exposure time and microwave power in a nontrivial manner. In terms of ore floatability, the experimental tests have been carried out on a sample of 75 microm in size under different exposure times. The results show that both ore concentrate recoveries and grades of nickel and copper are significantly enhanced after microwave treatment of the ore with relative increases in recovered concentrate, grade of nickel, and grade of copper of 26 wt%, 15 wt%, and 27%, respectively, at a microwave power of 1330 kW and after 30 s of exposure time.

F wave latency--a frequent and early involved nerve conduction parameter in young diabetic subjects

F-wave latency measurement is a sensitive parameter of diabetic neuropathy than the conduction velocities. This study was carried out to measure F-wave latency and to see which conduction parameters are affected frequently and early. A total number of 62 patients of which 32 newly diagnosed and 30 controls were included in the study. Ulnar motor nerve conduction velocity was found slowed in 6(18.75%) diabetic subjects, but F-wave latency was found prolonged in 16(50%) diabetic subjects. 28(87.5%) diabetic subjects had normal peroneal nerve conduction velocity but peroneal F wave was found prolonged in 17(53.12%) diabetic subjects. This result suggests that F-wave latency is more frequently & early involved conduction parameter in diabetic subjects.

Sequence analysis of the full-length cloned DNA of a chicken anaemia virus (CAV) strain from Bangladesh: evidence for genetic grouping of CAV strains based on the deduced VP1 amino acid sequences

Chicken anaemia virus (CAV) was detected in the bursa of Fabricius of a 4-week-old chicken obtained from an outbreak of acute infectious bursal disease in Bangladesh. Repeated attempts to grow this virus in MDCC-MSB1 cells were not successful. A full-length PCR amplicon of the genome of this strain, designated as BD-3 CAV, was cloned and sequenced. The complete nucleotide sequence and the deduced amino acid sequence were compared with those of 12 other CAV strains. The genetic analysis of the amino acid sequences of VP1 indicated the possible existence of genetic groups among CAV strains, as BD-3 CAV along with four other strains (CIA-1, L-028, Isolate 704 and TR-20) formed a distinct lineage. These strains have four signatory amino acids in VP1, such as 75I/T, 97L, 139Q and 144Q, out of which the latter two are located in a small hydrophilic peak.

Involvement of the hap gene (mucinase) in the survival of Vibrio cholerae O1 in association with the blue-green alga, Anabaena sp

Mucinase is a soluble haemagglutinin protease, which may be important for the survival of Vibrio cholerae in association with mucilaginous blue-green algae (cyanobacteria). A comparative survival study was carried out with an Anabaena sp. and a wild-type V. cholerae O1 strain hap+ gene (haemagglutinin-protease), together with its isogenic mutant hap (hap-deleted gene). A simple spread plate technique was followed to count culturable V. cholerae O1 on taurocholate tellurite gelatin agar plate. The fluorescent antibody technique of Kogure et al. (1979) was used for the microscopical viable count of V. cholerae O1. Polymerase chain reaction (PCR) and Southern blot hybridization were carried out to detect a lower number of viable but nonculturable (VBNC) V. cholerae O1 from the laboratory-based experiments. The wild and mutant V. cholerae O1 strains survived in culturable form for 22 and 10 days. respectively, in association with the Anabaena sp., with the difference being statistically significant (P < 0.01). The fluorescent antibody technique, PCR, and hybridization results also showed that the wild strain survived better in the VBNC state than did the mutant VBNC strain in association with an Anabaena sp. These results indicate that the enzyme mucinase may play an important role in the association and long-term survival of V. cholerae O1 with a mucilaginous blue-green alga, Anabaena sp.

Establishment of a simple method for measurement of chronic blood flow in uterine artery of pregnant cows

Blood flow to the gravid uterine horn of seven multiparous Holstein cows (mean +/- SD, BW = 625.5 +/- 82.4 kg; age = 4.7 +/- 1.7 yr; parity = 2.9 +/- 1.1 yr) was measured from d 225 of gestation to parturition using transit-time ultrasonic blood flow probes placed around the middle uterine artery. Surgery was conducted on d 215 of gestation. The cows were sedated with xylazine and local anesthesia (procaine or bupivacain hydrochloride) during surgery. The surgical operations were conducted at the flank of standing cows. A transit time ultrasonic flow probe ("S" series, diameter 12 or 14 mm, Transonic Systems Inc., Ithaca, NY) was fitted surgically around the uterine artery of each cow. Surgery was completed within 2 h of anesthesia, and the animals recovered rapidly following surgery. Uterine blood flow (UBF, L/min) was recorded at 10-s intervals for 1395 min; these values were averaged to determine UBF. Cows exhibited normal gestation lengths (279.1 +/- 7.4 d), gave birth to normal healthy calves (birth weight = 40.6 +/- 6.6 kg), and had no retained placentas. The UBF increased significantly (P < 0.01) from d 225 (6.67 +/- 2.47) to d 249 (8.23 +/- 2.89) of gestation, but the latter UBF was similar to that of d 266 (8.38 +/- 2.70). The increased UBF after d 225 indicates increased demand of nutrients of fetus with the progress of gestation. The range of mean UBF varied widely among individual cows from 4.1 L/min to 12.2 L/min. Our method is useful for chronic measurement of UBF in cows for nutritional or physiological studies and does not require sophisticated facilities or special surgical technique.

Molecular and antigenic characterization of Bangladeshi isolates of infectious bursal disease virus demonstrate their similarities with recent European, Asian and African very virulent strains

Three isolates of infectious bursal disease virus (IBDV), obtained from chickens in Bangladesh in 1999 and designated as BD 1/99, BD 2/99 and BD 3/99, were characterized. In an antigen capture enzyme-linked immunosorbent assay using a panel of VP2-specific neutralizing monoclonal antibodies (mAb), all three isolates showed a mAb-binding profile similar to that of very virulent IBDV (vvIBDV) strains. In contrast to the classical virulent strains, they did not react with mAb 3 and mAb 4. Molecular characterization was performed by direct sequencing of a 677-base pair cDNA corresponding to the VP2 variable domain of the polyprotein gene, synthesized by a reverse transcription-polymerase chain reaction. In comparison to the classical virulent strains, the Bangladeshi isolates were found to have five amino acid substitutions in this region. Four of these changes, Pro222Ala, Val256Ile, Leu294Ile and Asn299Ser, were also observed in other vvIBDV strains. The fifth substitution, Glu300Ala, was similar to that in some African strains of IBDV. The results support the observation that antigenically and genetically similar vvIBDV strains, first observed in Europe in the late 1980s, have spread to most parts of the world in a short period of time.

The genome segment B encoding the RNA-dependent RNA polymerase protein VP1 of very virulent infectious bursal disease virus (IBDV) is phylogenetically distinct from that of all other IBDV strains

A full-length cDNA clone of the segment B of the very virulent infectious bursal disease virus (IBDV) strain BD 3/99 was constructed and the full-length nucleotide sequence was established. The nucleotide sequence encoding VP1, an RNA-dependent RNA polymerase, of BD 3/99 was aligned with that of 17 other IBDV strains including six very virulent, three classical virulent, five classical attenuated, one antigenic variant and two serotype 2 strains. The VP1 genes of all very virulent strains were 97.5% to 99.8% identical. With the exception of an atypical Australian strain, 002-73, all of the classical virulent or attenuated and antigenic variant strains were also 97.5% to 100% identical. Serotype 2 strains showed only 4-6% divergence from serotype 1 classical virulent or attenuated strains; in contrast, however, the very virulent strains were 10.5% to 12.5% divergent from the classical virulent or attenuated strains as well as serotype 2 strains. Analysis of the deduced amino acid sequence of VP1 revealed 17 common, including 8 unique amino acid substitutions in the very virulent strains. In the phylogenetic tree the very virulent strains formed a distinct cluster and all other strains including classical virulent, attenuated and antigenic variant strains and even serotype 2 strains were grouped together. It is suggested that the VP1 of very virulent IBDV is phylogenetically distinct from that of all other IBDV strains and probably originated from a hitherto unidentified source.

Integrated management of radioactive strontium contamination in aqueous stream systems

A combination of biomass treatment, fluidized bed/membrane reactor, and a minimum-suspension fluidized bed reactor is proposed to remove strontium cations from aqueous solutions, such as those generated by nuclear reactors. After conducting a series of screening tests, three adsorbents were selected for their suitability and high adsorptive capacity. The proposed combination uses Chlorella vulgaris in a packed column, followed by the fluidized bed/membrane reactor with bentonite powder in suspension. The membrane is primarily used to retain bentonite powder in the reactor. However, the same can be designed to remove additional amount of contaminant from the aqueous stream. The final separation is carried out in a fluidized bed containing resins that are suspended with minimal airflow. In laboratory scale, a flow rate of 600 ml/h was achieved for 30 min during which period the inlet concentration of 100 mg/l was reduced to 2.5 mg/l at the outlet. Bio-encapsulation with thermophilic bacteria and subsequent separation is proposed at this point in order to reduce the concentration to an even lower level. The proposed separation scheme offers an acceptable solution to removing strontium while minimizing the generation of secondary waste.

Human egasyn binds beta-glucuronidase but neither the esterase active site of egasyn nor the C terminus of beta-glucuronidase is involved in their interaction

Lysosomal beta-glucuronidase shows a dual localization in mouse liver, where a significant fraction is retained in the endoplasmic reticulum (ER) by interaction with an ER-resident carboxyl esterase called egasyn. This interaction of mouse egasyn (mEg) with murine beta-glucuronidase (mGUSB) involves binding of the C-terminal 8 residues of the mGUSB to the carboxylesterase active site of the mEg. We isolated the recombinant human homologue of the mouse egasyn cDNA and found that it too binds human beta-glucuronidase (hGUSB). However, the binding appears not to involve the active site of the human egasyn (hEg) and does not involve the C-terminal 18 amino acids of hGUSB. The full-length cDNA encoding hEg was isolated from a human liver cDNA library using full-length mEg cDNA as a probe. The 1941-bp cDNA differs by only a few bases from two previously reported cDNAs for human liver carboxylesterase, allowing the anti-human carboxylesterase antiserum to be used for immunoprecipitation of human egasyn. The cDNA expressed bis-p-nitrophenyl phosphate (BPNP)-inhibitable esterase activity in COS cells. When expressed in COS cells, it is localized to the ER. The intracellular hEg coimmunoprecipitated with full-length hGUSB and with a truncated hGUSB missing the C-terminal 18-amino-acid residue when extracts of COS cells expressing both proteins were treated with anti-hGUSB antibody. It did not coimmunoprecipitate with mGUSB from extracts of coexpressing COS cells. Unlike mEg, hEg was not released from the hEg-GUSB complex with BPNP. Thus, hEg resembles mEg in that it binds hGUSB. However, it differs from mEg in that (i) it does not appear to use the esterase active site for binding since treatment with BPNP did not release hEg from hGUSB and (ii) it does not use the C terminus of GUSB for binding, since a C-terminal truncated hGUSB (the C-terminal 18 amino acids are removed) bound as well as nontruncated hGUSB. Evidence is presented that an internal segment of 51 amino acids between 228 and 279 residues contributes to binding of hGUSB by hEg.

Active site residues of human beta-glucuronidase. Evidence for Glu(540) as the nucleophile and Glu(451) as the acid-base residue

Human beta-glucuronidase (hGUSB) is a member of family 2 glycosylhydrolases that cleaves beta-D-glucuronic acid residues from the nonreducing termini of glycosaminoglycans. Amino acid sequence and structural homology of hGUSB and Escherichia coli beta-galactosidase active sites led us to propose that residues Glu(451), Glu(540), and Tyr(504) in hGUSB are involved in catalysis, Glu(451) being the acid-base residue and Glu(540) the nucleophile. To test this hypothesis, we introduced mutations in these residues and determined their effects on enzymes expressed in COS cells and GUSB-deficient fibroblasts. The extremely low activity in cells expressing Glu(451), Glu(540), and Tyr(504) hGUSBs supported their roles in catalysis. For kinetic analysis, wild type and mutant enzymes were produced in baculovirus and purified to homogeneity by affinity chromatography. The k(cat)/K(m) values (mM(-1).s(-1)) of the E540A, E451A, and Y504A enzymes were 34,000-, 9100-, and 830-fold lower than that of wild type hGUSB, respectively. High concentrations of azide stimulated the activity of the E451A mutant enzyme, supporting the role of Glu(451) as the acid-base catalyst. We conclude that, like their homologues in E. coli beta-galactosidase, Glu(540) is the nucleophilic residue, Glu(451) the acid-base catalyst, and Tyr(504) is also important for catalysis, although its role is unclear. All three residues are located in the active site cavity previously determined by structural analysis of hGUSB.