A study on measuring the 222Rn in the Buriganga River and tap water of the megacity Dhaka

Radon (222Rn), an inert gas, is considered a silent killer due to its carcinogenic characteristics. Dhaka city is situated on the banks of the Buriganga River, which is regarded as the lifeline of Dhaka city because it serves as a significant source of the city's water supply for domestic and industrial purposes. Thirty water samples (10 tap water from Dhaka city and 20 surface samples from the Buriganga River) were collected and analyzed using a RAD H2O accessory for 222Rn concentration. The average 222Rn concentration in tap and river water was 1.54 ± 0.38 Bq/L and 0.68 ± 0.29 Bq/L, respectively. All the values were found below the maximum contamination limit (MCL) of 11.1 Bq/L set by the USEPA, the WHO-recommended safe limit of 100 Bq/L, and the UNSCEAR suggested range of 4-40 Bq/L. The mean values of the total annual effective doses due to inhalation and ingestion were calculated to be 9.77 μSv/y and 4.29 μSv/y for tap water and river water, respectively. Although all these values were well below the permissible limit of 100 μSv/y proposed by WHO, they cannot be neglected because of the hazardous nature of 222Rn, especially considering their entry to the human body via inhalation and ingestion pathways. The obtained data may serve as a reference for future 222Rn-related works.

Comparison of the growth performance of available layer strains in Bangladesh

Various factors have been reported that affect the growth performance of layers, such as genetics, nutrition, environment, and disease. Attaining appropriate growth is essential to ensure profit. The present study was conducted to make comparative analyses of the growth performance of four commonly available layer strains in Bangladesh. A total number of 400-layer day-old chicks (DOCs), 100 from each of NOVOgen brown, ISA brown, Hy-Line brown and Bovans brown were used for the experiment. The birds were equally divided and randomly assigned to 4 treatments having 4 replications in each treatment comprising 25 birds per replication. All birds fed diet with similar composition and provided with the identical care and management up to 16 weeks of age. The results from this study revealed that there were no significant differences among the growth performances (weekly body weight, feed intake, uniformity and survivability) of four commonly available layer strains and all the strains followed the standard very closely. There were also no statistical differences based on the economic parameters of the strains compared in this study. Taken together, it may be concluded that the layer strains available in Bangladesh are highly competitive and suitable for local climatic conditions and the farmers can rely any of them. Bangladesh Journal of Animal Science 51 (4): 163-168  

Anorectal Malformations and Associated Anomalies in Children

Anorectal malformations (ARM) incorporate a broad spectrum of diseases, can affect both sexes, and involve the distal anus and rectum as well as the uro-genital tracts. Defects range from the minor which can be treated easily with an excellent outcome, to those are complex and often associated with other anomalies are difficult to manage with poor functional prognosis. This study was done to observe the hospital incidence of Anorectal malformations, frequency of types, sex distribution and spectrum of associations with ARM. The effects of presence of associated anomalies on morbidity and mortality also observed. Detailed history, clinical examinations and relevant investigations were performed for the primary and as well as the associated anomalies. A total of 80 patients were admitted in the department of pediatric surgery in Mymensingh Medical College Hospital during the period of June 2016 to May 2017. Age of the patients was ranging from 1-180 days with the mean age of 0.49±1.002 months. Male: Female ratio was 1.6: 1. Among them 48(60%) were high and 32(40%) were low variety of ARM. In male 37(46.2%) had high and 13(13.7%) were low variety whereas in female 11(13.7%) were high and 19(23.7%) had low ARM. Associated anomalies were seen in 25(31.2%) patient -18 in males and 7 in females; 20 in high and 5 in low ARM. Associated anomalies were uro-genital 11(13.8%), cardiovascular 10(12.5%), vertebral 4(5%), limb defects 3(3.5%) and others 2(2.5%). Four patients have more than one anomaly. Anorectal malformations occur more in boys than girls. Males were more likely to have high lesions and without fistula was the common defect. Low variety ARM were found more in females with Anovestibular fistula is the commonest defect. The most common associated anomalies were recto urinary fistula (13.8%). Associations were more in high than low ARM but not significant (p>0.05). Post operative complications were more in high ARM in both sexes with associated anomalies. The effects of types and associations on morbidity and mortality were significantly different (p<0.05).

Mn-site doping and its effect on inverted hysteresis and thermomagnetic irreversibility behavior of antiferromagnetic Mn5Si3alloy

The structural and magnetic behavior of Mn-site doped intermetallic manganese silicide alloys of nominal compositions Mn5-xAxSi3(x= 0.05, 0.1, 0.2 and A = Ni, Cr) have been investigated with a focus to the inverted hysteresis behavior and thermomagnetic irreversibility. Room temperature x-ray powder diffraction data confirm that all the doped alloys crystallize in hexagonalD88type structure with space groupP63/mcm. The doped alloys are found to show paramagnetic-collinear antiferromagnetic (AFM2)-noncollinear antiferromagnetic (AFM1) transitions during cooling from room temperature. A significant decrease in the critical values of both AFM1-AFM2 transition temperatures and fields have been observed with the increasing Ni/Cr concentration. Inverted hysteresis loop, field-induced arrest, and thermomagnetic arrest, the key features of the undoped Mn5Si3alloy, are found to be significantly affected by the Mn-site doping and eventually vanishes with 4% doping.

Supplementation of natural minerals on the performance of broiler

An experiment was conducted to evaluate the efficacy of AZOMITE® as source of natural minerals on growth performance of commercial broiler. A total of 1,020 day-old Cobb 500 male broiler chicks were randomly allocated to 5 dietary treatments with 6 replications per treatment having 34 chicks in each pen. The five dietary treatments were: (i) basal diet without AZOMITE®, (ii) basal diet with 0.25% AZOMITE®, (iii) basal diet with 0.50% AZOMITE® which was recommended by manufacturer, (iv) basal diet with 0.75% AZOMITE® and (v) basal diet with 1.0% AZOMITE®. Broilers were reared in open-sided gable type house for a period of 32 days. Results showed that the supplementation of AZOMITE® had significant effect on growth performance (p<0.01) of broilers. Live body weight (LBW), body weight gain (BWG), average daily gain (ADG), feed intake (FI), feed conversion ratio (FCR), European efficiency factor (EEF) and gain cost of the birds fed various levels of AZOMITE® were significantly improved as compared to the control. Meat characteristics results indicated that the treatments had no significant effect on dressing percent, thigh, drumsticks and breast percentage among the dietary groups. Taken together, it may be concluded that the supplementation of AZOMITE® in commercial broiler at 0.50 to 1.0% improved live weight, feed intake and feed conversion ratio of commercial broilers. Bang. J. Anim. Sci. 2019. 48 (2): 92-98

Outcome of Single Stage Correction of High Variety of Anorectal Malformation

The standard treatment of high variety anorectal malformation (ARM) is the staged approach. A growing interest in one stage correction of high variety ARM was noted recently. The aim of this study was to examine the feasibility, safety and outcome of single stage correction of High variety ARM. This prospective study was carried out in the Department of Paediatric Surgery, Mymensingh Medical College Hospital (MMCH), Mymensingh, Bangladesh from July 2012 to September 2013. It was conducted among 30 patients, all having high ARM. The type of ARM was diagnosed by clinical examinations and imaging studies like Invertogram and Transperineal USG. Other associated congenital anomalies were excluded. Out of 30 patients 11(36.67%) were male and 19(63.33%) were female. The age incidence ranges from 2 days to 5 months with the mean±SD age 1.70±1.63 months. The type of fistula present along with ARM in male varies from rectobulber urethral fistula, recto prostatic urethral fistula, recto vesical fistula and in one case without any fistula. Type of fistula was rectovestibular, rectovaginal and one cloacal malformation among the female patients. The treatment modalities in male patients vary in transabdominal pull through anorectoplasty and PSARP, in which the former was done more (72.73%). In case of female patients, treatment modalities vary in transabdominal pull through and anorectoplasty and transfistulous anorectoplasty, with the later done more (52.63%). Regarding post operative complications, there was 1(14.29%) wound infection in male and 1(33.33%) in female, partial wound disruption in 1(14.29%) male patient, mucosal prolapse 2(28.57%) in male and 1(33.33%) in female, anal stenosis 1(14.29%) in male and 1(33.33%) in female, perianal soiling in 1(14.29%) male patient. All the complications were treated by adopting various measures. One stage correction of High variety ARM in both male and female patients is technically feasible. The safeties of this approach depend on the adherence to strict inclusion criteria. The early post operative complications are acceptable and can be managed successfully.

Growth performance of local and genetically improved chicken of Bangladesh

The experiment was conducted to compare the growth performance among four genotypes of indigenous chicken namely Non-descriptive Native (ND), genetically Improved Native (IN), Hilly (HC) and Naked Neck (NN) of Bangladesh under free-range rearing system.  A total of 288 day old chicks (DOC) from four genotypes were divided into four treatments having eight replications of each for a period of 12 weeks under free-range system with supplementation of commercial broiler diet. During first 4 weeks, all chicks were kept together, whereas chicks of ND was brooded in the same room but separated by a partition. At 5 weeks of age chicks were randomly distributed to the selected farmers. Growth parameters were recorded to determine the comparative growth performance among four genotypes of chicken. The highest body weight (1110.76 g/bird) was achieved by HC, followed by IN (900.63 g/bird) and NN (831.13 g/bird) at 12 weeks of age. The lowest body weight (734.13 g/bird) however was found in ND chicken. During the growing period under free range rearing (5-12 weeks), HC group consumed the highest amount of feed (2697.02 g/bird) with an average FCR of 3.06 while the lowest feed consumption (2666.13 g/bird) with the highest FCR of 4.90 was observed in ND. IN consumed (2674.63 g/bird) feed with an average FCR of 3.92 and BLRI improved NN consumed (2668.13 g/bird) feed with an average FCR of 4.19. Live weight gains in all the four genotypes of indigenous chicken were changed almost in a similar pattern. Significant differences were observed in live weight, dressing percentage, breast meat, drumstick, thigh meat among the four genotypes of chicken. The HC was superior to other genotypes of indigenous chicken including ND in terms of growth performance, meat yield characteristics and net returns. Bang. J. Anim. Sci. 2018. 47 (2):76-84

Peptic Ulcer Disease in Bangladesh: A Multi-centre Study

The incidence of peptic ulcer has steadily declined through out the world. This decreasing trend is also noticeable in this subcontinent. The point prevalence of peptic ulcer (PUD) in Bangladesh was around 15% in eighties. The aim of this study was to see the present prevalence of peptic ulcer at endoscopy and to identify changing trends in the occurrence of peptic ulcer in Bangladesh. This retrospective analysis of the endoscopic records of multiple tertiary referral centres of Dhaka city were done from January 2012 to July 2013. A total of 5608 subjects were the study samples. We included those patients having peptic ulcer in the form of duodenal ulcer, benign gastric ulcer including pre-pyloric ulcer and gastric outlet obstruction due to peptic ulcer. Duodenal ulcer and benign gastric ulcer were found in 415(7.4%) and 184(3.28%) patients respectively and gastric outlet obstruction due to peptic ulcer was found in 23(0.40%) patients.

Pattern of Changes in the Findings among the Patients Undergoing Diagnostic Esophagogastroduodenoscopy in Bangladesh

This cross-sectional observational study was conducted in the Department of Gastroenterology, Bangabandhu Sheikh Mujib Medical University, Sir Salimullah Medical College and Mitford Hospital, Holy family Red Crescent Medical College and Hospital and Popular Diagnostic Centre, Shantinagar branch, Dhaka, Bangladesh from January 2012 to July 2013. Study subjects were included in the study irrespective of age and sex having different upper GI tract. Complaints like dysphagia, heart burn, abdominal pain/dyspepsia, nausea, vomiting, haematemesis and/or malena, anorexia, unexplained anemia, weight loss etc. All the findings of oesophagus, stomach and duodenal lesions were observed and data were recorded. The results were considered positive based on the macroscopic appearance using standard diagnostic criteria. During the study period endoscopy was performed in 5608 subjects. Among which 2968(52.92%) were male and 2640(47.07%) were female. The patients age range from 7 years to 108 years. The majority of the patients were from 40-50 years. Normal findings were observed among 3321(59.21%) cases. Gastroduodenal erosions were present among 684(12.19%) cases, Oesophageal varices in 444(7.91%) cases, duodenal ulcer diseases in 415(7.40%) cases and gastric ulcer in 184(3.28%) cases. Ca stomach was found among 165(2.94%) cases. A number of diseases were identified through this procedure. Current study observed a large proportion of patients (40.79%) had positive upper GI endoscopy.

Note: development of fast heating inert gas annealing apparatus operated at atmospheric pressure

Here, we report the development of a simple, small, fast heating, and portable, homemade, inert gas (Ar) atmospheric annealing setup. Instead of using a conventional heating element, a commercial soldering rod having an encapsulated fast heating heater is used here. The sample holder is made of a block of stainless steel. It takes 200 s to reach 700 °C, and 10 min to cool down. The probability of oxidation or surface contamination has been examined by means of x ray photoelectron spectroscopy of virgin Cu sample after annealing at 600 °C. In addition, we compare the annealing of a hydrogenated carbon nitride film (HCN(x)) in both a conventional vacuum and our newly developed ambient Ar atmosphere setup.

Antimicrobial activities of tocklai vegetative tea clones

Thirty-one Tocklai vegetative (TV) tea clones contained caffeine and total catechin 44.39 and 227.55 mg/g dry weight of leaves, respectively. The (-)-epigallocatechin gallate (EGCG) was the most abundant (109.60 mg/g) followed by -(-)-epigallocatechin (EGC, 44.54 mg/g), (-)-epicatechin gallate (ECG, 41.74 mg/g), (-)-epicatechin (EC, 27.42 mg/g) and +catechin (4.25 mg/g). Total catechins were highest in TV 20 (509.7 mg/g) and lowest in TV 6 (71.7 mg/g). The tea clones that contain high level of total catechin exhibited the strongest antimicrobial activity. Among caffeine and flavanol compounds, theaflavins (TF) present in black tea possess a similar antimicrobial potency as EC present in fresh leaves, and that the conversion of catechins to TF during fermentation in making black tea tends to alter their antimicrobial activities. The bioactive molecules other than catechins present in tea leaves may also contribute towards antimicrobial activity.

Expression of Toll-like receptors and avian β-defensins and their changes in response to bacterial components in chicken sperm

The aim of the present study was to examine whether chicken sperm express mRNA of Toll-like receptors (TLR) and avian β-defensins (avBD), and whether the expression of avBD in the sperm are regulated by the interaction of TLR-2 and TLR-4 with their corresponding ligands. Total RNA was extracted from fresh sperm and mRNA expression for TLR and avBD were examined by reverse-transcription PCR. Changes in the expression of avBD-5, avBD-9, avBD-10, and avBD-12 in the sperm after incubation with lipopolysaccharide (LPS; TLR-4 ligand) or lipopeptide (Pam3CSK4; TLR-2 ligand) were examined by real-time PCR. Among 8 types of TLR, PCR products of 7 types, namely, TLR-2 to TLR-5, TLR-7, TLR-15, and TLR-21, were identified in the sperm. The sperm also expressed cluster of differentiation 14 (CD14), which is required for the binding of LPS to TLR-4. Out of 14 avBD types reported in the chicken, a total of 9 types, namely, avBD-1, avBD-3, avBD-5, and avBD-7 to avBD-12 were expressed by the sperm, whereas avBD-5, avBD-9, avBD-10, and avBD-12 showed dense signals on the gel. Expression levels of avBD-5, avBD-9, avBD-10, and avBD-12 were significantly increased in the sperm stimulated with LPS, and that of avBD-5 was also enhanced by Pam3CSK4. These results suggest that avian sperm have the ability of the innate host defense to protect themselves from infection in the male and female genital tracts.

Effect of environmental iodine deficiency (EID) on foetal growth in Nigeria

BACKGROUND & OBJECTIVES

There is scarcity of information on impact of iodine deficiency on growth and development of newborns, both pre-term and term babies. The present study was carried out to see the impact of iodine deficiency (ID) on the intrauterine foetal growth and development in terms of birth weight (BW) in an African population living in an iodine deficient zone.

METHODS

The maternal and cord serum thyroid parameters at term delivery (38-40 wk of gestation) were measured and correlated with the birth weights of the corresponding newborns, and the results compared between those assessed in an ID zone (Jengere region of Bassa district, Plateau State, Nigeria) and with that of non ID (Control) zone, Jos, the State capital.

RESULTS

The level of maternal and neonatal thyroid function were significantly reduced in the group with low birth weights (<2.5 kg) as compared to the level seen in normal birth weights category in both control (Jos) and ID (Jengere) regions. Both in non ID and ID regions the maternal serum thyroxine (T4), thyroxine binding globulin (TBG) and free thyroxine index (FT4I) were positively correlated (P<0.005) with BW of term babies while thyroid stimulating hormone (TSH) (P<0.005) and thyroxine binding capacity (TBK) (P<0.05) showed negative correlation. Maternal T3 and T3/T4 ratio did not show any correlation with BW in Jos, while in the ID region of Bassa the BW showed a positive correlation (P<0.005) with the maternal serum T3 and T3/T4 ratio. Cord serum analysis of the term babies revealed that the BW was positively correlated with its T4, triiodothyronine (T3), TBG, FT4I and T4/TBG ratio (Jos only) (P<0.005) in both ID region of Bassa and non ID control zone of Jos. Cord serum TSH and TBK showed negative correlation (P<0.005) with BW. Thyrotrophin releasing hormone (TRH) stimulation test revealed that mothers with small for date (SFD) babies at term were more hypothyroid compared to the level of thyroid function seen in the women delivering normal babies.

INTERPRETATION & CONCLUSION

Maternal thyroid hormone plays a significant role in the intrauterine foetal growth and development, and the smaller babies and their corresponding mothers, in an ID affected area are functionally sub-thyroid in greater proportion due to prevailing long standing environmental iodine deficiency (EID). Maternal T3 is an important factor in the defence of foetus in ID regions.

Dairy farm investigation on Shiga toxin-producing Escherichia coli (STEC) in Kolkata, India with emphasis on molecular characterization

An investigation was conducted to determine the distribution, virulence gene profile and phenotypes of Shiga toxin-producing Escherichia coli (STEC) strains within a dairy farm in Kolkata, India by characterizing the STEC strains isolated from healthy dairy cow and calf stool samples, raw milk and farm floor swabs from July 2001 to March 2002. Primary screening by multiplex-PCR detected stx1 and stx2, the common virulence genes of STEC, in 18.9% of cow faeces, 32.4% of calf stool samples, 21.6% of farm floor swabs and 4.5% of raw milk samples and viable STEC were recovered from 4.5, 9.9, 8.1 and 1.8% of the corresponding PCR-positive samples. Strains harbouring stx1 (63.3%) and hlyA (53.3%) were frequently detected compared to eae (13.3%). Most of the strains harboured similar sets of reported virulence genes common among isolates from diarrhoea patients. Most of the strains also exhibited multidrug resistance, sorbitol fermentation and produced enterohaemolysin. The randomly amplified polymorphic DNA-PCR (RAPD-PCR) profile of the STEC strains isolated from the farm milieu revealed diverse banding patterns and clonal analysis demonstrated that the strains from different sources were not identical but showed some genetic relatedness. The study demonstrates the potential of dairy farm for housing virulent STEC.

The drug sensitivities of Plasmodium falciparum in the Sonitpur district, Assam, India

Falciparum malaria is an ongoing problem in the foothills of Northeast India. Evaluation of the drug sensitivities of P. falciparum was carried out in four endemic villages of the Sonitpur District of Assam, involving 218 cases who were tested in vivo over 35 days. Chloroquine resistance was detected at the RI level in 29 cases (13%) and RII level in 8 cases (4%). No RIII chloroquine resistant cases were detected in the study. RI resistance was observed in the age groups 6-10 years, 11-14 years, and 15 years and above in 16%, 17%, and 13%, respectively. RII level resistance was observed in 4% of all those groups combined. All the RI and RII resistant cases responded well to a single dosage of Metakelfin (sulfamethoxypyrazine I.P 1,500 mg and pyrimethamine I.P 75 mg).

Neonatal chemical hypothyroidism in Nigeria

To investigate the level of neonatal chemical hypothyroidism (NCH), thyroid function was measured in the cord blood of 271 neonates in an area with a high prevalence of endemic goitre, Bassa (n = 140), and a nonendemic area, Jos (n = 131), in Plateau State, Nigeria. NCH was defined as T4 < 40 nmol/L and TSH > 49 mU/L and borderline compensated NCH as T4 31-50 nmol/L and TSH 41-49 mU/L. NCH was detected in 16.4% of neonates in Bassa and in 3.8% in Jos. Borderline compensated NCH was detected in an additional 18.6% in Bassa and 8.4% in Jos. Contamination of foodstuffs and water by iodine-containing antiseptics and disinfectants during the antenatal period, in addition to factors responsible for endemic goitre, e.g. iodine deficiency and goitrogens, are considered to be responsible for the high prevalence of NCH in the Bassa area. As most infants' thyroid function recovers with time, the former might be a more important factor in the aetiology of NCH.

Effect of growth medium on hydrophobicity of Staphylococcus epidermidis

The present study was undertaken to evaluate the effect of growth medium on expression of hydrophobicity of Staphylococcus epidermidis. A total of 24 hydrophobic isolates of S. epidermidis, determined by n-hexadecane adherence assay (HAA) earlier were included. Five different growth media: horse blood agar (HBA), brain heart infusion agar (BHIA), brain heart infusion broth (BHIB), tryptic soy broth (TSB) and proteose peptone broth (PPB) were used. All 24 isolates exhibited the reproducible hydrophobicity when grown on HBA; however, 20 (83.33%), 19 (79.16%), 15 (62.50%) and 13 (54.16%) isolates were found to be hydrophobic when grown in BHIA, BHIB, TSB and PPB, respectively. HBA was found to be the most suitable medium for detection of hydrophobicity of S. epidermidis followed by BHIA or BHIB.

Epidemiological and entomological aspects of malaria in forest-fringed villages of Sonitpur district, Assam

BACKGROUND & OBJECTIVES

Detailed epidemiological and entomological studies were undertaken in forest-fringed villages and a Tea Estate in Sonitpur, Assam to assess the malaria situation.

METHODS

Door-to-door active surveillance was carried out to collect blood samples. Thick and thin blood smears stained with Giemsa were used for malaria parasite detection. Mosquito collections were made using CDC miniature light-traps and hand catch methods from dusk-to-dawn.

RESULTS

48% SPR, 49.1 Pf% was recorded from the study villages. Children between 10 and 14 years were most sufferers. Per trap night density of mosquitoes in human dwellings was 204.3 and in cattlesheds--908.7, An. minimus accounted for 20.7% of total malaria vectors.

INTERPRETATION & CONCLUSION

The results showed high malaria risk in the study villages. High vector density with high parity rate, poor socio-economic conditions, lack of awareness, poor sanitation and congenial atmosphere for mosquito proliferation are aggravating the malaria situation more complex in the study area.

Early detection of prostate cancer: evaluating the diagnostic performance of prostate specific antigen by comparing with histological technique among africans

This study was conducted to investigate the diagnostic performance characteristics of prostate specific antigen (PSA) by comparing serum PSA value with histological findings in patients suspevted of having prostate cancer in Aminu Kano Teaching Hospital. Nigeria. Clinical and Laboratory records were examined and collated for serum PSA values, together with histological findings of biopsy specimen, clinical diagnosis, age of patients, and mode of presentation. The serum PSA values were determined by ELECSYS 1010 autoanalysers Roche, Germany based on electrochemiluminescence immunoassay technique. The results show that serum PSA values increase with age in the assymptomatic non-cancer patients who came for medical check up but were within normal limit. In prostatic disease conditions PSA values were raised in benign prostatic hyperplasia 35.957± 4.0315ng/ml, in undifferentiated carcinoma 56.22±4.295ng/ml and adenocarcinoma >100ng/ml as compared to the normal range (0-4ng/ml). These cases were confirmed by histological diagnosis. It is concluded that PSA evaluations is a sensitive marker for prostate cancer but because of various other conditions that affect serum PSA concentration, other methods of investigations such as Digital Rectal examination, Trans Urethral Ultra-Sonography and histological examination should be combined to confirm diagnosis. Prognosis of patients will be better if early diagnosis is made.

Shiga toxin producing Escherichia coli infection: current progress & future challenges

Shiga toxin producing Escherichia coli (STEC) is a newly emerged pathogen that has been the focus of immense international research effort driven by its recognition as a major cause of large scale epidemics and thousands of sporadic cases of gastrointestinal illness. It produces a severe bloody diarrhoea that is clinically distinct from other types of diarrhoeal diseases caused by other enteric pathogens. One of the most important areas of current exploration concerns how STEC enters our food chain, an investigational avenue that begins with the ecology of STEC in animals and in the environment. A variety of foods have been identified as vehicles of STEC-associated illness and this makes the organism one of the most serious threats to the food industry in recent years. The pathogenesis of STEC is multifactorial and involves several levels of interaction between the bacterium and the host. STEC strains carry a set of virulence genes that encode the factors for attachment to host cells, elaboration of effective molecules and production of two different types of Shiga toxins. These genes are found in the locus of enterocyte effacement (LEE), lamboid phages, and a large virulence associated plasmid. The publication of the complete genome sequence of Esch. coli O157:H7 chromosome offers a unique resource that will help to identify additional virulence genes, to develop better methods of strain detection and in the understanding of the evolution of Esch. coli through comparison with the genome of the non-pathogenic laboratory strain Esch. coli K-12. These research efforts in turn, should lead to development of new potent and cost effective anti-Stx therapies or vaccines and thereby major improvement in human health world-wide.

Environmental isolates of Citrobacter braakii that agglutinate with Escherichia coli O157 antiserum but do not possess the genes responsible for the biosynthesis of O157 somatic antigen

While searching for Escherichia coli O157 in the aquatic environment of Calcutta using an immunodetection procedure, we fortuitously detected five strains of Citrobacter braakii, which cross-reacted with the commercially available O157 polyvalent antiserum. The five C. braakii isolates gave positive results when a sensitive dot-ELISA was performed with E. coli O157 monoclonal antibody. Further, the O157 monoclonal antibody recognized the bands of proteinase K treated whole cells of lipopolysaccharide of all the C. braakii isolates. Apart from weak reactions with two or three of the DNA probes, all the C. braakii strains did not hybridize with the other probes spanning the minimum region required for O157 O-antigen biosynthesis. These strains did not possess any of the virulence genes that are commonly found in the Shiga toxin-producing E. coli (STEC) specially the serotype O157: H7. Therefore, it appears that the serological cross-reaction between C. braakii and E. coli O157 antiserum is based on structural mimicry between the O-polysaccharide of C. braakii and E. coli O157.

Evaluation of botanicals as repellents against mosquitoes

Repellent properties of three plant extracts--essential oil (steam distillate) of Zanthoxylum limonella (fruits), Citrus aurantifolia (leaf) and petroleum ether extract of Z. limonella (fruits) were evaluated as repellent against Aedes (S.) albopictus mosquitoes in mustard (Dhara) and coconut (Parachute) oil base under laboratory conditions. Three concentrations--10, 20 and 30% of the repellents were evaluated. Repellents in mustard oil afforded longer protection time against the bites of Aedes (S.) albopictus mosquitoes than those in coconut oil. At 30% concentration, 296-304 min protection time was achieved by the test repellents in mustard oil base while repellents in coconut oil exhibited 223.5-245 min protection time at the same concentration. Oil of Z. limonella gave the highest protection time against the bites of Aedes (S.) albopictus mosquitoes at all the concentrations than other herbal repellents tested both in mustard and coconut oil.

Antibiotic resistance, virulence gene, and molecular profiles of Shiga toxin-producing Escherichia coli isolates from diverse sources in Calcutta, India

Antibiotic resistance, virulence gene, and molecular profiles of Shiga toxin-producing Escherichia coli (STEC) non-O157 strains isolated from human stool samples, cow stool samples, and beef samples over a period of 2 years in Calcutta, India, were determined. Resistance to one or more antibiotics was observed in 49.2% of the STEC strains, with some of the strains exhibiting multidrug resistance. The dominant combinations of virulence genes present in the strains studied were stx(1) and stx(2) (44.5% of strains) and stx(1), stx(2), and hlyA (enterohemorrhagic E. coli hemolysin gene) (19% of strains). Only 6.4% of the STEC strains harbored eae. The diversity of STEC strains from various sources was assessed by random amplification of polymorphic DNA (RAPD). STEC strains that gave identical or nearly similar DNA fingerprints in RAPD-PCR and had similar virulence genotypes were further characterized by pulsed-field gel electrophoresis (PFGE). Identical RAPD and PFGE profiles were observed in four sets of strains, with each set comprising two strains. There was no match in the RAPD and PFGE profiles between strains of STEC isolated from cows and those isolated from humans. It appears that the clones present in bovine sources are not transmitted to humans in the Calcutta setting although these strains showed evolutionary relatedness. Maybe for this reason, STEC has still not become a major problem in India.

Comparative evaluation of hydrophobicity measures for virulence determination of Staphylococcus epidermidis from hospitalized patients & healthy individuals

BACKGROUND & OBJECTIVES

Hydrophobicity is one of the recognized markers for identifying pathogenic strains of Staphylococcus epidermidis. A number of tests are available for measuring the hydrophobic character but three tests viz., salt aggregation test (SAT), n-hexadecane adherence assay (HAA) and xylene adherence assay (XAA) are in common practice with different degrees of sensitivity. However, in the Indian context, no systematic study has been reported on the hydrophobicity of S. epidermidis. Hence, the present study was undertaken to compare the three methods for hydrophobicity measurement for identifying the pathogenic isolates of S. epidermidis.

METHODS

Of the 597 samples obtained from milker's and butcher's (hand and nose), hospitalized pre-operative patients (hand, nose, ear), and post-operative patients (blood) examined, 212 isolates of S. epidermidis were recovered using established laboratory procedures. The isolates were screened by the three tests viz., SAT, HAA and XAA. The identified hydrophobic isolates were further tested by mouse inoculation method.

RESULTS

Of the 212 S. epidermidis isolates studied, 24 (11.32%), 23 (10.84%) and 4 (1.88%) were found to be hydrophobic as detected by HAA, XAA and SAT, respectively. No isolates from apparently healthy individuals were found to be hydrophobic by SAT while 13 (8.76%) and 10 (8.24%) strains from apparently healthy individuals were detected to be hydrophobic by HAA and XAA, respectively. Seven (33.38%) isolates each were hydrophobic by HAA and XAA and 4 (22.22%) by SAT among the isolates from hospitalized post-operative patients.

INTERPRETATION & CONCLUSION

The results suggested that there was no difference in the number of strains detected as hydrophobic by HAA and XAA, and any of the two tests may be used for screening the hydrophobic strains of S. epidermidis from healthy individuals and patients.

Diclofenac sodium injection sterilized by autoclave and the occurrence of cyclic reaction producing a small amount of impurity

A known impurity is formed in the production of a parenteral dosage form of diclofenac sodium if terminally sterilized by autoclave. This impurity has been detected as 1-(2,6-dichlorophenyl) indolin-2qone, which is also an intermediate from which diclofenac sodium is generally synthesized. It is only the condition of the autoclave method (i.e., 123 +/- 2 degrees C) that enforces the intramolecular cyclic reaction of diclofenac sodium forming the indolinone derivative and sodium hydroxide. The formation of this impurity has been found to depend on the initial pH of the formulation. The reaction follows first-order kinetics, and the energy of activation is 5.34 kcal/mol. The other excipients in the formulation do not have a role in this reaction. The concentration of the impurity in the resultant product in the ampule goes beyond the limit of the raw materials in the pharmacopoeias. It is thus preferable to use an alternative sterilization method; that is, an aseptic filtration method in which the formation of this impurity can be avoided.

Epidemiological observations on malaria in some parts of Darrang District, Assam

A study on malaria conducted in tribal villages of Darrang district, Assam during April 1994 to March 1995 revealed that the malaria incidence due to Plasmodium falciparum was considerably high. Slide positivity rate (SPR) ranged between 2.3 to 45.67 per cent with transmission from May to October. P. falciparum was the dominant species (91.7 per cent) followed by P. vivax (7.25 per cent) and mixed infection (Pv + Pf = 1.05 per cent). Malaria cases were recorded throughout the year in all the age groups including infants, however, age groups between 0-1 and 21-30 years were more affected. Among 17 anophelines collected, Anopheles vagus, An. jamesii, An. crawfordi and An. minimus were the most abundant species. Known vectors of malaria like An. annularis, An. culicifacies, An. minimus, An. philippinensis and An. varuna were detected. Perennial transmission of malaria was attributed to low socio-economic conditions, poor surveillance and inadequate intervention measures.

Recovery and characterization of a chimeric rinderpest virus with the glycoproteins of peste-des-petits-ruminants virus: homologous F and H proteins are required for virus viability

Rinderpest (RP) and peste-des-petits-ruminants (PPR) are two important diseases of domestic ruminants. To improve on currently available vaccines against PPR, we have created cDNA copies of the RP virus genome in which either the fusion (F) or hemagglutinin (H) gene, or both, was replaced with the corresponding gene from PPR virus. It was necessary to develop a modified rescue system in which the T7 RNA polymerase was provided by a recombinant fowlpox virus and the entire rescue procedure took place in Vero cells before we could obtain live virus from these chimeric constructs. No virus was recovered when only one of the glycoprotein genes was changed, but a chimeric virus containing both F and H genes from PPR virus was reproducibly rescued from cDNA, indicating that a virus-specific functional interaction takes place between the F and H proteins. The rescued virus expressing the PPR glycoproteins grew more slowly in tissue culture than either parental virus and formed abnormally large syncytia. Goats infected with the chimera showed no adverse reaction, as assessed by clinical signs, temperature, leukocyte count, virus isolation, and serology, and were protected from subsequent challenge with wild-type PPR virus.

Improved technique for transient expression and negative strand virus rescue using fowlpox T7 recombinant virus in mammalian cells

The suitability of recombinant T7 polymerase produced using either the highly attenuated MVA strain of vaccinia (MVA-T7) or fowlpox virus (FP-T7) for transient expression and negative strand virus rescue was compared in two mammalian cell lines (MDBK and Vero) and in primary cells of bovine, ovine and caprine origin. Such primary cells are more permissive for the growth of wild type strains of morbilliviruses, such as Rinderpest virus and Peste des petits ruminants virus. MVA-T7 was found to be highly cytopathic in the primary cells, multiplying rapidly and killing the cells within 3-5 days of infection, even when very low multiplicities of infection (MOI) were used. In contrast, FP-T7, which appeared to express similar amounts of T7 polymerase, was found to be non-cytopathic in a variety of primary and established cell lines of mammalian origin and was suitable for use in virus rescue experiments. MDBK cells and primary cells, unlike Vero cells, could not be efficiently transfected and so were unsuitable for virus rescue. Optimal conditions for rinderpest virus rescue in Vero cells were established using FP-T7 in place of MVA-T7. This system will be suitable for rescuing other viruses which grow in Vero cells.

Entomological and epidemiological studies on malaria in Rajmahal range, Bihar

The epidemiological investigations carried out in six tribal villages in Rajmahal range hill in south Bihar revealed average slide positivity rate (SPR) 25.1 ranging between 9.8 and 37.8 per cent. Plasmodium falciparum was the dominant parasite which accounted 64.2 per cent of the total infections. Results of mass blood survey indicated the presence of high percentage of asymptomatic carriers of malaria parasites in the local populace. In an entomological survey, 25 species of mosquitoes under five genera were collected in 20 trap nights. The average density of mosquitoes recorded was 230.6 per trap night. Anopheles mosquitoes alone accounted 72.8 per cent of the total collection whereas malaria vectors Anopheles maculatus, An. minimus, An. philippinensis, An. varuna and An. annularis accounted 32.8 per cent of the total anophelines collected. Both anopheline and culicine mosquitoes were found susceptible to DDT (4 per cent) and malathion (5 per cent) in 30 min exposure. Dissection of malaria vectors An. minimus, An. maculatus and An. philippinensis revealed very high percentage of parity rate (77.8 per cent) which gives a strong indication about their vectorial status in the transmission of malaria. Poor socio-economic condition, lack of sense of hygiene worsen the situation in the presence of asymptomatic carriers.

Preliminary clinical investigation of the contraceptive efficacy and chemical pathological effects of RICOM-1013-J of Ricinus communis var minor on women volunteers

The seeds of Ricinus communis Linn, RICOM-1013-J, administered as a single oral dose of 2.3-2.5 g once per 12 months protected against pregnancy in 50 women volunteers for a period of one year. The antifertility and contraceptive efficacy of the seed was demonstrated in this study. Clinical observation revealed very minimal side effects. Some of the side effects investigated included headache, nausea, vomiting, weight gain, loss of appetite, raised blood pressure and dysmenorrhoea. Furthermore, both the renal and liver functions were not affected as revealed by urea, electrolyte and creatinine values as well as total bilirubin, conjugated bilirubin, serum albumin, total protein and transaminases values when compared with control values. In addition cholesterol and phospholipids were not significantly altered. When all these results are considered together, it seems unlikely that the antifertility and contraceptive efficacy of RICOM-1013-J is due to hormonal mechanisms alone since side effects, renal and liver function, and cholesterol effects attributable to oestrogen and/or progesterone were minimal in the volunteers.

Chemical, pathological and toxicological studies of the effects of RICOM-1013-J of Ricinus communis var minor on women volunteers and rodents

RICOM-1013-J (Ricinus communis var minor) administered orally once to each of 12 women volunteers at a dose of 2.5-2.7 g per 8 months, protected against pregnancy over a period of 7-8 months of study. A study of the effect of a contraceptive dose (20 mg/kg) on metabolic parameters in rat (food and water in-take, urine and faecal output and body weight) over a period of 4 months showed a slight decrease in all the parameters in the first 1-8 weeks. This effect was reversible attaining pretreatment levels from week 16. The LD(50) in an acute toxicity test in mice was 63.1 +/- 16.0 g/kg s.c. Determination of blood urea, sodium (Na(+)), potassium (K(+)), chloride (Cl(-)) and bicarbonate (HCO$_¿3¿ ¿-¿$)as a measure of renal function and alkaline phosphatase (ALP), transaminases (GPT and GOT) and transpeptidases (GGT) as a measure of liver function showed that liver function profiles in pretreated rats were not significantly different from control (p < 0.05) on day 21 to day 150. However, serum levels of ALP and GGT at day 120 to day 150 were moderately but significantly elevated (p > 0.05) compared with the control. There were no significant changes in renal function profiles in pretreated rats (p < 0.05) compared with the control. The results of the liver and renal function profiles in women volunteers showed that there were no significant (p < 0.05) changes in renal functions on day 206 following RICOM-1013-J administration. However, serum levels of ALP and GGT showed a slight rise in about 70% of volunteers, whereas bilirubin and transaminases levels were normal. The present results indicate a very high efficacy and margin of safety of RICOM-1013-J in women volunteers. The increase in ALP and GGT in both animal and women volunteers suggest mild intrahepatic cholestatic changes which may be attributed to an oestrogenic effect of RICOM-1013-J.

Field evaluation of herbal mosquito repellents

Repellent properties of Zanthoxylum armatum DC. Syn. Z. alatum Roxb. (Timur), Curcuma aromatica (Jungli haldi) and Azadirachta indica (Neem) oils were evaluated against mosquitoes in mustard (Brassica sp.) and coconut (Cocos sp.) oil base and compared with synthetic repellent. Dimethyl phthalate (DMP) as standard. Timur and jungli haldi afforded better protection in the both the base at all the concentrations. Tepellents in mustard oil gave longer protection time than those in coconut oil. At 0.57 mg/cm2 concentration timur oil gave significantly higher protection both in mustard (445 min) as well as coconut oil (404 min) than the other repellents and DMP.

Capillaria hepatica, a parasite of zoonotic importance--a brief overview

This review briefly elucidates the biology and mode of transmission of the parasite capillaria hepatica, an cuimial parasite. Occasional transmitted to man.