Impact of the COVID-19 Pandemic on the Management of Gallbladder, Biliary Tract, and Pancreatic Diseases

Introduction Biliary diseases are a major acute general surgical burden. Laparoscopic cholecystectomy is the gold standard surgical procedure, although it was discontinued during an outbreak. Effective management permits decisive therapy, symptom alleviation, and fewer hospitalizations and complications. Throughout the initial COVID-19 situation, surgical procedures for patients were delayed. Invasive services were required to employ conservative or non-operative therapy, which could lead to increased recurring presentations and biliary-pancreatic problems. Aim Examining the impact of COVID-19 on the outcomes and hospitalizations of patients suffering from gallstone, biliary tract, and pancreatic diseases.  Methods The retrospective analysis included patients with the following ICD-10 codes who presented to our unit: cholelithiasis (K80), cholecystitis (K81), and acute pancreatitis (K85). We compared the interval of the first COVID-19 pandemic wave, from March to August 2020, with the period before the pandemic, referred to as Pre-COVID-19. After applying exclusion criteria, a total of 868 patients were enrolled in the trial, having initially recruited around 1,400 individuals using these codes. Patients with inaccurate coding, cancer, or non-stone disease were excluded (e.g., alcoholic pancreatitis). The demographic information, admission details, investigations, surgical therapy, operating specifics, and postoperative complications of the patients were noted. Changes in surgical management, patient representation, and postoperative complications were the key outcomes. Results A statistically significant (p<0.05) rise was seen in repeat presentations in the COVID group, most likely due to the failure of definitive treatment. The other outcome is the distribution of presentations was comparable, patients with acute cholecystitis and gallstone pancreatitis showed statistically significant (p<0.05) lower rates of definitive therapy. Conclusion During the COVID period, all surgeries except those for cancer were halted. Unknown causes led to several consequences related to the gallbladder, biliary tract, and pancreas. Patients with cholecystitis, gallstone pancreatitis, and pancreatic inflammation experienced a lower probability of treatment. The increase in hospitalizations and self-presentations indicated that definitive therapy, designed to restrict COVID-19 exposure, actually increased patient risk. Despite this risk, we had no COVID-19 instances in our cohort. The evaluation of the long-term consequences of the pandemic on acute pancreatitis and its care will require a large-scale, multicenter investigation.

Physical, Psychological and Social Impact of COVID-19 Pandemic on Healthcare Workers at a COVID Designated Bangladeshi Public Hospital

The world has been devastated facing the outbreak of a novel infectious disease known as Corona virus disease (COVID-19). This has been declared as a pandemic by the World Health Organization. The frontline health care workers, who are directly involved in the diagnosis, treatment and care of patients with COVID-19, are taking significant personal risks on their own health and those of their family members. Objectives of the study include establishing the physical, psychological and social impact experience by the healthcare workers serving in public hospitals of Bangladesh. This prospective cross-sectional observational study was carried out at Kuwait Bangladesh Friendship Government Hospital, the first Covid-19 designated hospital of Bangladesh between the 1st June and the 31st August, 2020. A total of 294 doctors, nurses, ward boys and ailed healthcare workers were included in this study via purposive sampling. The study found statistically significant (p value 0.024) difference of medical co-morbidities between Covid-19 positive and Covid-19 negative groups of health care professionals. Significant association was found between duration of work and presence during aerosol generating procedure with COVID infectivity of the study subjects. 72.8% respondents experienced public fear of contracting the virus from them and 69.0% noticed negative attitude of the society towards them. Eighty five percent (85.0%) did not get any community support during this pandemic crisis. The health care professionals engaged in COVID-19 treatment have been taking significant personal risk on their life in terms of physical, psychological and social perspective. Providing safeguard to the health care workers are integral components of public health measures for addressing the COVID-19 pandemic. Special interventions to promote their physical wellbeing and arrangement of adequate psychological training need to be immediately implemented to cope up this critical situation.

Surveillance and office management of low-grade Ta bladder tumors

OBJECTIVE

Patients with low-grade (LG), grade 1-2, Ta bladder cancer (BC) will frequently have a "recurrence". However, they rarely progress in stage. Although current guidelines mention surveillance and office management for these new or recurrent tumors, transurethral resection (TURBT) is the most common treatment. The purpose of this study is to determine if surveillance and/or office cautery is safe.

MATERIALS AND METHODS

This study was conducted as a retrospective case series analysis of 45 patients who had recurrent LG Ta appearing bladder cancer (BC) and were managed primarily with surveillance and/or office cautery. Patients with carcinoma in-situ were excluded. The primary outcome was stage progression.

RESULTS

Median follow up was 62 months. 41 (91%) patients did not progress in stage. Three patients recurred with HG T1 BC; one is receiving systemic immunotherapy. One patient developed HG T2 BC and was treated with a bladder preservation protocol. 40 (89%) patients underwent office cauterization. Eleven received BCG and 26 received post-cautery intravesical chemotherapy. Five (11%) patients developed HG BC during follow up. No patients died. None of the 17 (38%) Hispanic patients had progression.

CONCLUSIONS

Active surveillance and/or office cautery for patients with small recurrent LG Ta bladder tumors is safe, reduces cost and improves quality of life by avoiding TURBTs.

209 Breast Lymphoma Treatment Outcomes in a Pakistani Population: 20 Years of Experience at a Single Centre

Background

Breast lymphomas constitute a rare disease entity. To date, limited relevant data have been reported. We therefore here present a review of breast lymphoma patients treated at a single centre over 20-year period, focusing on histological types, treatment modalities and outcomes.

Method

We identified patients who were diagnosed and treated for breast lymphoma at a single centre from January 1995 to January 2014 and extracted data regarding patient demographics and clinical data.

Results

Twenty-seven patients with breast lymphoma were identified, of which 3 were males. Median age at diagnosis was 37 years (range:22-76 years). Chemotherapy was main stay of treatment and 55.6% patients also received radiation to affected breast. At our institute, only 3 patients, all with progressive disease, had surgery performed to achieve local palliation. Complete response after chemotherapy was seen in 63% patients and partial response in 7.4%, while 26% patients demonstrated disease progression. The mean follow up was 46.8 months. Seven patients (33.3%) who were alive at last follow up, as well as 1 patient who died, survived more than 5 years after diagnosis.

Conclusions

Patients with breast lymphoma should receive aggressive treatment, with combination of chemotherapy and radiation therapy. Surgery should be limited for diagnosis and palliation of local symptoms in cases of progressive disease.

210 Prognosis of Breast Cancer in Very Young Age (Less Than 30 Years)

Background

Breast cancer diagnosed at younger age has aggressive biology being triple negative and high grade and associated with poor prognosis.

Method

Retrospectively data of 121 patients age 30 years or younger registered during the year 2008 was reviewed. Demographics studied were age at diagnosis, gender, pregnancy, or lactation associated, family history, histopathological diagnosis, stage of the disease, receptors, type of treatment, response, local recurrence, distant relapse, survival.

Results

One patient was male. Age range 20 -30 years, single patient had bilateral involvement. half 50.4%(n = 61) patients had locally advanced disease at presentation. Pregnancy/ lactation associated breast cancer was seen in 29.8%(n = 36). Most common stage was stage III (52.1%) & stage II (33.9%). IDC was the most common histology 94.2% (n = 114) Triple negative was most common molecular subtype present in 46.3%(56). After 5 years follow up, local recurrence was observed in 12.4%(n = 15), cancer related deaths were 42.1%(n = 51).

Conclusions

Breast cancer in very young has very aggressive tumor biology, needs aggressive treatment with surgery, chemotherapy, radiation therapy and hormonal therapy, furthermore there is need to identify possible environmental factors which may contribute in the rising incidence in this age group.

The impact of fluid optimisation before induction of anaesthesia on hypotension after induction

Intra-operative hypotension is a known predictor of adverse events and poor outcomes following major surgery. Hypotension often occurs on induction of anaesthesia, typically attributed to hypovolaemia and the haemodynamic effects of anaesthetic agents. We assessed the efficacy of fluid optimisation for reducing the incidence of hypotension on induction of anaesthesia. This prospective trial enrolled 283 patients undergoing radical cystectomy and randomly allocated them to goal-directed fluid therapy (n = 142) or standard fluid therapy (n = 141). Goal-directed fluid therapy patients received fluid optimisation based on stroke volume response to passive leg raise before induction; those with positive passive leg raise received intravenous crystalloid fluid boluses until stroke volume was optimised. Baseline mean arterial pressure was measured on the morning of surgery and on arriving in the operating theatre. This post-hoc analysis defined haemodynamic instability as either a > 30% relative drop in mean arterial pressure compared with baseline or absolute mean arterial pressure < 55 mmHg, within 15 min of induction. Forty-two (30%) goal-directed fluid therapy patients underwent fluid optimisation after finding an intravascular fluid deficit via passive leg raise testing; 106 (75%) goal-directed fluid therapy and 112 (79%) standard fluid therapy patients met criteria for haemodynamic instability. There was no significant difference in the incidence of haemodynamic instability between the goal-directed fluid therapy and standard fluid therapy groups using absolute mean arterial pressure drop below 55 mmHg (p = 0.58) or using pre-surgical testing or pre-surgical mean arterial pressure values as baseline (p = 0.21, p = 0.89, respectively); however, the difference in the incidence of haemodynamic instability was significant using the operating theatre baseline mean arterial pressure (p = 0.004). We conclude that fluid optimisation before induction of general anaesthesia did not significantly impact haemodynamic instability.

IDENTIFICATION OF QTLs ON CHROMOSOME 1B FOR GRAIN QUALITY TRAITS IN BREAD WHEAT (TRITICUM AESTIVUM L.)

The present study was designed considering the importance of grain quality traits, genetic diversity and marker-trait association analysis in wheat. A significant amount of genetic diversity was found for various seed traits though the genotypes included in the study were found structured. The extent of polymorphism was high with a range of 2-13 alleles and average of 6.5 alleles per locus. Population structure was detected with 30 unlinked SSRs that divided the population of 92 genotypes in three sub-populations. Extensive LD extent was found on chromosome 1B with 42 SSRs specific for 1B chromosome. Marker-trait associations were determined using mixed linear model, where, population structure and kinship calculated on the basis of unlinked markers were covariated with 1B specific markers and traits data. Eight QTLs for five traits including protein, gluten contents, test weight bread and chapati making quality. Protein content, test weight, bread quality and Glu-B1 were found significantly associated with primers WMC419 (32 cM); WMC128 (30 cM), WMC419 (32 cM); WMC818 (17 cM) and WMC416 (44 cM), respectively.

The case in favour of probiotics before, during and after pregnancy: insights from the first 1,500 days

Successful human reproduction requires microbial homeostasis in the female reproductive tract, and colonisation of the newborn with beneficial microbes. In order to prevent several complications associated with dysbiosis, the administration of probiotics is more often being considered. The objective of the enclosed review was to examine the rationale for probiotic utility before and during pregnancy and in the early phase of infant life. The conclusions emerged from a panel of researchers who met during the International Scientific Association for Probiotics and Prebiotics (ISAPP) workshop held in Washington, DC, USA in 2015. The group concluded based upon the current literature, that a case can be made for the use of a specific sets of probiotic organisms during the first 1,500 days of life, with the goal of a healthy pregnancy to term, and a healthy start to life with lowered risk of infections and inflammatory events. The key to successfully translating these recommendations to practice is that products be made available and affordable to women in developed and developing countries.

Priapism of the Newborn - A Case Report

Neonatal Priapism is a rare condition and its causes differ from that in childhood and adult. Management also is challenging as the ultimate goal is the preservation of normal erectile function. Most of the cases are idiopathic. A spontaneous detumescence occurs in majority of cases, so initially conservative non-surgical treatment is advocated. Here we report a case of a newborn presenting with priapism on the 1st day of life. Detumescence was achieved on the 8th day of life with conservative treatment.

Application of SCAR markers linked with mungbean yellow mosaic virus disease-resistance gene in Pakistan mungbean germplasm

Mungbean yellow mosaic virus disease (MYMVD) caused by single-stranded DNA begomovirus is the most prominent threat to the mungbean crop in Pakistan. Mungbean genotypes consisting of 127 varieties/lines were screened for MYMVD under natural field conditions. No genotypes were found to be immune or highly resistant against MYMVD. Genotypes showing resistant and tolerant responses in field screening trials were screened using sequence characterized amplified region (SCAR) markers linked with the MYMVD-resistance gene. SCAR markers amplified the desired band only in the resistant and tolerant genotypes, while no amplification was observed in susceptible genotypes. SCAR markers will be useful for future breeding and varietal developmental programs and mungbean genotypes can be screened on the molecular level.

Supratentorial glioblastoma multiforme metastasizing to the cervical spinal cord

Cases of glioblastoma multiforme (GBM) metastasizing to the leptomeninges or the intramedullary spine are rare and their prognosis are relatively poor. We present a case of supratentorial glioblastoma WHO grade IV which was later diagnosed to have cervical intramedullary metastasis 7 months after the primary surgery.

A young man with solitary trichoepithelioma of upper lip

A 25-year-old man presented with a long-standing history of asymptomatic, skin-colored papule on cutaneous part of upper lip. Histopathologic examination of the papule demonstrated trichoepithelioma. The patient had no family history. He had also no history of similar lesion at same site or elsewhere. The patient was otherwise asymptomatic. Clinician excised the lesion as a part of treatment. Clinical differential diagnosis was sebaceous cyst and basal cell carcinoma.

Identification and authentication of Rosa species through development of species-specific SCAR marker(s)

Roses (Rosa indica) belong to one of the most crucial groups of plants in the floriculture industry. Rosa species have special fragrances of interest to the perfume and pharmaceutical industries. The genetic diversity of plants based on morphological characteristics is difficult to measure under natural conditions due to the influence of environmental factors, which is why a reliable fingerprinting method was developed to overcome this problem. The development of molecular markers will enable the identification of Rosa species. In the present study, randomly amplified polymorphic DNA (RAPD) analysis was done on four Rosa species, Rosa gruss-an-teplitz (Surkha), Rosa bourboniana, Rosa centifolia, and Rosa damascena. A polymorphic RAPD fragment of 391 bp was detected in R. bourboniana, which was cloned, purified, sequenced, and used to design a pair of species-specific sequence-characterized amplified region (SCAR) primers (forward and reverse). These SCAR primers were used to amplify the specific regions of the rose genome. These PCR amplifications with specific primers are less sensitive to reaction conditions, and due to their high reproducibility, these species-specific SCAR primers can be used for marker-assisted selection and identification of Rosa species.

Molecular characterization of urdbean (Vigna mungo) germplasm related to resistance against urdbean leaf crinkle virus

Urdbean (Vigna mungo) is an important pulse crop grown worldwide. Urdbean leaf crinkle virus (ULCV) is a pathogen of urdbean found in Pakistan that causes huge losses in yield. Forty urdbean varieties/lines were screened against the virus under field conditions during spring season 2009. None of the lines appeared to be highly resistant or resistant. On the basis of a 0-5 disease rating scale and disease severity index, genotypes varied significantly in their reaction to ULCV. Four lines (M-6206, IAM-382-15, IAM-133, and Mash-1) were moderately resistant, eight were rated as moderately susceptible, and 21 as susceptible; the remaining seven lines were highly susceptible. RAPD analyses revealed an extensive amount of variation, which could be used for cultivar identification. Genetic differentiation among urdbean genotypes was similar to the field screening data. The varieties 6065-3 and 6206 were highly susceptible and moderately resistant, respectively, to ULCV under field conditions, confirmed by the RAPD analysis. These varieties were the most diverse varieties in the similarity matrix (67.2%), while the varieties IAM-382-9 and 07M003 were the most similar (98.4%). This information will help in the recognition of available resistant germplasms that can resist this disease and will be utilized for urdbean improvement in Pakistan.

Elucidation of thermotolerance diversity in cotton (Gossypium hirsutum L.) using physio-molecular approaches

Cotton (Gossypium hirsutum) is an important cash crop, but high temperature during its growing season is one of the major factors that limit its productivity. This problem compels plant breeders to breed for heat tolerance, which can help to overcome this challenge. It is very important to make a comprehensive screening of heat-tolerant genotypes so that only the best are chosen. Here we report the combined use of several techniques that can help breeders to screen their germplasm. Twelve cultivated cotton genotypes were evaluated for thermotolerance, using assays that included electrolyte leakage, chlorophyll accumulation and protein profiling, as well as RAPDs to assess genetic diversity. Two genotypes (B-557 and NIAB-78) showed tolerant behavior in three thermotolerance assays. RAPD analysis results showed maximum similarity in a range of 86.7-66.7% between the genotypes MNH-554 and CIM-443. We conclude that combined use should be made of relative electrolyte leakage, chlorophyll stability and differential display with SDS-PAGE to aid in screening for stress tolerance. RAPD-based diversity analysis will further help to improve the efficiency of breeding programs.

Estimation of genetic distance based on RAPDs between 11 cotton accessions varying in heat tolerance

The genetic distance of 11 cotton genotypes varying in heat tolerance was studied using RAPD markers. Fifty-three random decamer primers were used for the estimation of genetic distance. Among the 53 RAPD primers, which were custom synthesized by GeneLink Inc., UK, 32 were polymorphic and 21 were monomorphic. The 32 polymorphic primers produced 273 fragments, with a mean of 8.3 fragments per primer. The number of polymorphic bands produced in the 11 cotton accessions ranged from 1 to 31. Primer GLC-20 produced 31 polymorphic bands, while two primers, GLB-5 and GLC-12, produced one polymorphic band each. A range of 88.89 to 42.48% genetic similarity was observed among the 11 cotton accessions. The highest genetic similarity was observed between FH-945 and BH-160 (88.89%), whereas the lowest value was found between NIAB-801/2 and FH-945 (42.48%). Unique amplification profiles were produced by most of the cultivars; the differences were sufficient to distinguish them from other genotypes. This confirms the efficacy of RAPD markers for the identification of plant genotypes. An accumulative analysis of amplified products generated by RAPDs was sufficient to assess the genetic diversity among the genotypes. This information should be helpful for formulating breeding and genome mapping programs.

Kala azar in Pregnancy

Kala azar (KA) is one of the most important tropical diseases. More so is the issue of KA in pregnancy. In this retrospective study we tried to find out the out come of pregnant patient treated with Sodium Antimony Gluconate (SAG) for KA in one of the most endemic area of Bangladesh, Fulbaria. SAG is the available and registered drug for treatment of KA patient with pregnancy in Bangladesh. A total of 16 pregnant women presented with KA during the study period of 2005 to 2009. Out of the 16 patients 11 had abortion and they were all with in the 16 to 22nd week of pregnancy. The abortion took place mostly on the 22nd to 24th day of treatment when the patient had become afebrile. Rest of the 5 patients was in their 30 to 34th week of pregnancy and had good obstetric outcome. All the 16 patients were clinically cured at the end of treatment. No follow up records were available and there was no data regarding the 5 children. It is of our opinion that the abortions were induced by SAG and therefore we recommend that SAG should not be used in early or mid pregnancy for treating KA.

Biodiversity in the sorghum (Sorghum bicolor L. Moench) germplasm of Pakistan

Sorghum ranks fifth in worldwide economic importance among cereal crops and is one of the most important summer annual grasses of Pakistan. As it is a very diverse crop, sorghum genetic fingerprinting requires an efficient marker system. We estimated genetic divergence among 29 sorghum (Sorghum bicolor) genotypes, including approved varieties and local and exotic lines collected from different ecological regions of Pakistan, using random amplified polymorphic DNA (RAPD) markers. A total of 125 RAPD loci, with an average of 66 loci per genotype, were used to calculate genetic divergence among these genotypes, of which 119 were polymorphic, showing 95% overall polymorphism. Genetic similarity ranged from 0.36 to 0.92, indicating a relatively broad genetic base. RAPD analysis revealed maximum similarity between the Indian III and K-A-113 sorghum genotypes (both exotic lines), while the F-601 and F-606 were observed to be the most diverse genotypes. Mean band frequency revealed by these RAPD primers ranged from 0.17 to 0.56, with an average of 0.36. The data presented here support the findings that RAPDs can be effectively used for studying genetic diversity in sorghum.

Adults with chronic cough in urban Bangladesh: healthcare utilization and management of cases by private practitioners

Tuberculosis (TB) case detection under the Directly Observed Treatment - Short-course (DOTS) strategy largely relies upon care seeking of chronic coughers and the actions taken by their healthcare providers. This study aimed to describe the healthcare utilization of people 15 years of age with a chronic cough in urban areas of Bangladesh and to understand their management by private practitioners. A community-based, household survey included 60,382 persons ≥ 15 years of age from two administrative areas of Dhaka City. A total of 1138 (2%) were identified to have had a cough for 3 weeks or more. This survey was linked to interviews of licensed and unlicensed practitioners in Dhaka and the Chittagong City Corporation of Bangladesh. Among identified coughers, 1046 (92%) were interviewed, of whom 648 (62%) reported having sought care from any provider. Among care seekers, 16% directly attended a DOTS facility. The remaining 84% sought care from the private sector, where less than 1% reported referral to a DOTS facility. Bivariate and multivariate assessments showed that care seeking from a licensed private practitioner or a DOTS centre was significantly associated with severity of the disease and previous diagnosis of TB.

Estimation of genetic distance between 10 maize accessions with varying response to different levels of soil moisture

Ten maize accessions (NC-9, A50-2, M-14, B-42, NC-3, T-7, N-48-1, B-34, USSR, and WFTMS) were studied to estimate the genetic distance on molecular level by random amplified polymorphic DNA. These accessions were selected on the basis of their variable responses against different levels of moisture. Twenty-five primers were used to test genetic diversity, of which 14 were observed to be polymorphic. Ninety-three loci were amplified; among these, 77 showed polymorphism and the other 16 were monomorphic. Primers A-13 and C-02 gave the most polymorphic bands, while primers A-01 and C-06 gave the fewest polymorphic bands. The genetic similarities of the 10 maize accessions ranged from 82.8 to 54.8%. Accessions USSR and WFTMS showed greatest similarity, and accessions M-14 and B-42 were found more dissimilar than the other accessions. On the basis of cluster analysis, these 10 accessions were classified in two major groups, A and B, and than further divided into sub-groups. The cluster analysis showed that accessions in the same group as well as in the sub-groups were similar in their physical and morphological characters, since the characters are controlled genetically.

Health needs and health-care-seeking behaviour of street-dwellers in Dhaka, Bangladesh

The study objective was to ascertain the extent to which the need for primary health care services among street-dwellers is being met through existing facilities. This community-based cross-sectional study was conducted in Dhaka city over a 12-month period from June 2007 to May 2008. The study population included ever-married females and males aged 15-49 years. Data for the study were collected through a community survey and exit interviews. Both bivariate and multivariate analyses were done. Seventy-two per cent of female and 48% of male street-dwellers interviewed were sick at the time of data collection. Twenty-one per cent of deliveries were conducted on the street. Eighty-nine per cent of the street-dwellers reported that their children aged less than 5 years had more than one symptom associated with acute respiratory infection during the last 2 weeks. Thirty-seven per cent of the females and 34% of the males interviewed reported that their accompanied children had diarrhoea. A few street-dwellers sought services for their health problems, and most went to the nearest pharmacy and to mobile clinics run by a non-governmental organization at night. Eighty-eight per cent of the female and 88% of the male street-dwellers used open space for their defecation. The street-dwellers are extremely vulnerable in terms of their health needs and health-care-seeking behaviours. There is no health service delivery mechanism targeting this marginalized group of people. Although the health, nutrition and population sector programme of Bangladesh designed programmes to ensure equitable essential services to all, this marginalized group of people was not targeted. The Ministry of Health and Family Welfare and private sectors should, thus, should focus future programmes to meet the needs of this extremely vulnerable group. Mobile and static clinics at night for street-dwellers may be potential programmes. Action research to assess the effectiveness of programmes is essential before large-scale implementation.

Bacterial enteropathogens of neonates admitted to an urban diarrhoeal hospital in Bangladesh

Data on the aetiology of diarrhoea in neonates are scarce, especially from developing countries including Bangladesh. A retrospective review of the electronic database of the Microbiology Laboratory of the International Centre for Diarrhoeal Disease Research, Bangladesh (ICDDR,B), was carried out to examine enteropathogens associated with diarrhoea in neonates. Stool specimens of the neonates on admission to the Dhaka Hospital of ICDDR,B were collected and sent to the laboratory for direct plating onto taurocholate tellurite gelatin agar, Salmonella-Shigella agar and MacConkey's agar. Stool specimens of 2511 neonates of either sex were examined. Bacterial pathogens were recovered from the stools of 699 (27.8%) of these neonates--a single bacterial pathogen from 670 neonates and more than one pathogen from 29 neonates. Vibrio cholerae, Shigella, Salmonella, Aeromonas spp. and Plesiomonas shigelloides were isolated from 294, 108, 52, 222 and 19, respectively, of the neonates. The year-wise isolation of these pathogens varied between 4.9-23.4%, 2.7-5.4%, 0-4.7%, 0-19.4% and 0-1.6%, respectively, of the neonates. The results of the study indicate that infection by V. cholerae, Shigella spp., Salmonella spp., Aeromonas and P. shigelloides is common in neonatal diarrhoea in Bangladesh.

A hierarchical graph neuron scheme for real-time pattern recognition

The hierarchical graph neuron (HGN) implements a single cycle memorization and recall operation through a novel algorithmic design. The HGN is an improvement on the already published original graph neuron (GN) algorithm. In this improved approach, it recognizes incomplete/noisy patterns. It also resolves the crosstalk problem, which is identified in the previous publications, within closely matched patterns. To accomplish this, the HGN links multiple GN networks for filtering noise and crosstalk out of pattern data inputs. Intrinsically, the HGN is a lightweight in-network processing algorithm which does not require expensive floating point computations; hence, it is very suitable for real-time applications and tiny devices such as the wireless sensor networks. This paper describes that the HGN's pattern matching capability and the small response time remain insensitive to the increases in the number of stored patterns. Moreover, the HGN does not require definition of rules or setting of thresholds by the operator to achieve the desired results nor does it require heuristics entailing iterative operations for memorization and recall of patterns.

Presence of neutral fat in stool and its association with aetiology and presenting features of diarrhoea in children

Enteric infections, impaired digestion, loss of villous cells, and poor absorption of fat may lead to presence of neutral fat in stool, particularly in children with diarrhoea. We aimed to examine the association between presence of neutral fat in stool and aetiology of diarrhoea and nutritional status of the patients at different age groups. A total of 13,171 patients aged 5 days-106 years enrolled in the Diarrhoeal Disease Surveillance System of the Dhaka Hospital of ICDDR,B during 1996-2001 were studied. Presence of neutral fat in faecal specimens, aetiology of diarrhoea, and nutritional status in children below 5 years of age were determined and analysed. Of the total study individuals, 7,671 (58%) had neutral fat in their faecal specimens. Neutral fat was more frequently present in faeces of individuals infected with rotavirus in all age groups or in enterotoxigenic E. coli (ETEC) infection in children 0-23 months old while compared with those who did not have these infections (p=0.005, p=0.014, respectively). Neutral fat was less frequently (p<0.001) present in malnourished 0-23 months old children. Presence of neutral fat in the stool in diarrhoea due to rotavirus and in young childhood ETEC diarrhoea signifies compromised gastrointestinal function due to these infections. The mechanism of persistence of neutral fat in the stool of such patients, and its nutritional and clinical implications require further studies.

Shigella serotypes among hospitalized patients in urban Bangladesh and their antimicrobial resistance

We studied the isolation of Shigella spp., and their antimicrobial resistance. S. flexneri (54 %) was most frequently isolated, followed by S. dysenteriae (20 %), S. boydii (16 %) and S. sonnei (10 %). Among S. flexneri (n = 122), 29 (24 %) were 2a, and 23 (19 %) were 2b. None of the Shigella strains were resistant to mecillinam or ciprofloxacin. Resistance to nalidixic acid was most frequent among S. dysenteriae type 1 (100%) followed by S. flexneri 2a (69%), and S. flexneri 2b (52 %). Systematic monitoring is needed to identify most prevalent serotypes, and to detect changes in the prevalence and antimicrobial resistance pattern.

Intercalation and controlled release of pharmaceutically active compounds from a layered double hydroxide

A series of pharmaceutically active compounds including diclofenac, gemfibrozil, ibuprofen, naproxen, 2-propylpentanoic acid, 4-biphenylacetic acid and tolfenamic acid can be reversibly intercalated into a layered double hydroxide, initial studies suggest that these materials may have application as the basis of a novel tuneable drug delivery system.

Wheat-germ aspartate transcarbamoylase: revised purification, stability and re-evaluation of regulatory kinetics in terms of the Monod-Wyman-Changeux model

A revised and simplified purification scheme for aspartate transcarbamoylase (ATCase) from wheat-germ is reported, with an eightfold increase in scale (yielding approximately 10 mg of the pure protein from 4 kg of wheat-germ), and improved characteristics of stability and regulatory kinetics. The ATCase obtained is greater than 96% pure, as judged by polyacrylamide gel electrophoresis. The long-term stability (i.e. on a time-scale of several hours to weeks) of the activity of the purified enzyme, under various storage conditions, was investigated. At 4 degreesC and pH 7.5, stability was found to be strongly dependent on protein concentration (increased stability at high concentration), buffer concentration (decreased stability at high buffer concentration) and the inclusion of glycerol (increased stability with increasing glycerol concentration). The enzyme is routinely stored at 4 degreesC, in 0. 05 m Tris/HCl buffer containing 25% glycerol and at high protein concentration (approximately 1 mg.mL-1, or 10 microm in trimers). Under these conditions, the half-life of the enzyme activity is greater than 300 days. Over the time-scale of kinetic experiments (up to 20 min), the diluted activity (at around 1 nm of ATCase, in the presence of ligands) is completely stable. The specific activity remains constant in the range 0.1-10 nm, in the absence and presence of ligands, showing that dissociation of the trimeric enzyme into its subunits is negligible. Steady-state kinetics were examined using the enzyme at a concentration of 1.3 nm. Initial-rate curves for both allosteric ligands, carbamoylphosphate (CP) and uridine 5'-monophosphate (UMP), showed pronounced sigmoidicity, each in the presence of the other. In the absence of UMP, initial-rate curves for CP are hyperbolic. The initial rate data fit reasonably well to a trimeric Monod-Wyman-Changeux model, suggesting a two-state conformational mechanism, greatly favouring the active (R) state when both ligands are absent, in which the R-state binds CP exclusively (dissociation constant = 23.2 microm), and the T-state binds UMP exclusively (dissociation constant = 0.49 microm). This regulatory behaviour was found to be quite stable, and was indistinguishable from that of the enzyme in a freshly made crude extract, even after storage of the pure sample for 5 months. This enzyme preparation is therefore free of the anomalous allosteric kinetics produced by a previous purification scheme, in which the affinity for UMP was markedly reduced, CP rate curves showed no sigmoidicity, while UMP rate curves had sigmoidicity exaggerated by a low maximum.

Effect of chronically infused adrenomedullin in two-kidney, one-clip hypertensive rats

The hypotensive effect of chronically infused adrenomedullin, a potent vasodilator peptide, was examined in conscious two-kidney, one-clip (2K-1C) hypertensive and sham-operated rats. They were infused with 1.0 microgram/h of synthetic human adrenomedullin for 14 days by means of osmotic minipumps. Control groups were infused on the same schedule with 0.9% saline. Systolic blood pressure was measured before and during the infusion. Plasma renin activity, aldosterone and human adrenomedullin concentrations were determined at day 14 of the infusion. A significant reduction of systolic blood pressure was observed in the adrenomedullin-infused 2K-1C rats at day 4, and systolic blood pressure remained significantly lower throughout the experiment compared to that of the control 2K-1C. A similar hypotensive effect was seen in the adrenomedullin-infused sham-operated rats. Both the plasma renin activity and aldosterone concentrations of the adrenomedullin-infused 2K-1C and sham groups were significantly reduced compared to those of the respective control, whereas, the plasma human adrenomedullin concentration in the adrenomedullin-infused groups was found to be within the physiological range. These findings demonstrated that chronically infused adrenomedullin had a hypotensive effect accompanied by significant reductions of plasma renin activity and plasma aldosterone concentration in 2K-1C hypertensive and sham-operated rats.

Hypotensive effect of chronically infused adrenomedullin in conscious Wistar-Kyoto and spontaneously hypertensive rats

1. The hypotensive effect of chronically infused human adrenomedullin (hAM), a potent vasodilator peptide that has been reported to have a natriuretic action, was examined in normotensive Wistar-Kyoto (WKY) rats and spontaneously hypertensive rats (SHR). 2. Conscious WKY rats and SHR were infused with 200 ng/h synthetic hAM for 14 days by means of osmotic minipumps. Control groups were infused at the same schedule with 0.9% saline. Systolic blood pressure (SBP) and daily urinary excretion of Na+ and K+ were measured before and during the infusion period. In addition, plasma renin activity (PRA), aldosterone and hAM concentrations were measured on day 14 of infusion. 3. A significant reduction in SBP was observed in hAM-treated SHR at day 2 and SBP remained significantly lower throughout the experiment compared with control SHR. Similarly, SBP in the hAM-treated WKY rats was found to be significantly lower than in control WKY rats during infusion. However, the hypotensive effect was not accompanied by any significant increase in urinary volume or Na+ excretion in hAM-treated rats of either strain. Chronic infusion with hAM significantly suppressed PRA and lowered the concentration of plasma aldosterone in WKY rats but not in SHR. The plasma aldosterone in WKY rats and SHR were 0.9 +/- 0.4 and 0.6 +/- 0.2 fmol/mL, respectively. 4. These findings demonstrate that chronically infused hAM has a hypotensive effect in both WKY rats and SHR without an increase in urinary volume or Na+ excretion at a plasma AM concentration within the physiological limit.

The anti-HIV activity and mechanisms of action of pure compounds isolated from Rosa damascena

Water and methanol extracts of Rosa damascena exhibited moderate anti-HIV activity. The anti-viral activities of 9 compounds isolated from the methanol extract were compared. The tetrahydroxyflavanone (kaempferol, 1), was effective in reducing the maturation of infectious progeny virus apparently due to selective inhibition of the viral protease. On the other hand the pentahydroxyflavone (quercetin, 2) and two 3-substituted derivatives of kaempferol appeared to inhibit HIV-infection by preventing binding of gp120 to CD4. 2-Phenylethanol-O-(6-O-galloyl)-beta-D-glucopyranoside 8 interacted irreversibly with gp120 and neutralized virus infectivity. The differences in the modes of action of 1 and 8 can account for the apparent synergy of their anti-viral activities.

Effects of adoptive transfer of immune spleen cells on worm growth and microfilaraemia in Brugia pahangi infection in Mongolian gerbils

Protective immunity against Brugia pahangi was examined after adoptive transfer of immune spleen cells. Spleen cells obtained from gerbils at 8 weeks post-infection (p.i.) with 100 infective larvae (L3) of B. pahangi were transferred into naive recipients, and then 24 h later, they were infected with 100 L3 of B. pahangi. The recipients given normal spleen cells and infected by the same manner served as controls. Microfilarial counts in the circulation were monitored at designated times after infection and worm burden and the size of individual female worm were determined at 16 weeks p.i. to evaluate the effects of adoptive immunization. In addition, eosinophil responses and serum antibody titres were examined during the course of infection. In the control group, microfilariae first appeared in circulation at 9 weeks p.i. and continuously increased in number throughout the course examined. In contrast, microfilaraemia was almost completely suppressed in the group given immune spleen cells. Although worm burden was comparable between the two groups, the average size of female adult worms recovered from the adoptively immunized group was significantly smaller than that from the control group. Eosinophil response was hastened and enhanced by adoptive transfer of immune spleen cells in the early stage of infection. Parasite-specific antibody response was also hastened by adoptive immunization. These results suggest that immune spleen cells could confer protective immunity mainly directed against adult B. pahangi.

Reserpine-induced sulphomucin production by goblet cells in the jejunum of rats and its significance in the establishment of intestinal helminths

The present investigation was undertaken to determine whether reserpine-induced increase in the sulphation of the small intestinal goblet cell mucins of rats affects the establishment of intestinal helminths. When Wistar rats were given daily intraperitoneal injections of reserpine for seven days and were then implanted intraduodenally with 500 Strongyloides venezuelensis adult worms, the number of adult worms established in the intestine of reserpine-treated rats was about half of that established in controls. Furthermore, when mast cell-deficient Ws/Ws rats were treated with reserpine and implanted concurrently with S. venezuelensis and Nippostrongylus brasiliensis adult worms, the establishment of the former, but not the latter, was significantly suppressed. These results imply that the physicochemical properties of the mucins produced and secreted by the small intestinal goblet cells may be critical for the establishment of particular species of intestinal helminths.

Goblet cell hyperplasia induced by Strongyloides venezuelensis-infection in Syrian golden hamster, Mesocricetus auratus

The goblet cell response was examined in the jejunum of the Syrian golden hamster, Mesocricetus auratus, following infection with an intestinal helminth, Strongyloides venezuelensis. After subcutaneous inoculation with 3000 infective larvae (L3), the number of adult worms in the small intestine remained stable up to day 20 and then decreased. Before infection, the number of goblet cells in the jejunum was about 70/10 villi. The number of goblet cells slowly increased, though not significantly, until day 20 post-infection, and then rapidly increased with an inverse relationship to the worm burden. By day 43, when adult worms were almost completely expelled, the number of goblet cells was about 3-fold higher than that of control animals. Similar vigorous goblet cell hyperplasia has not been reported in Strongyloides spp. infection in other experimental animals. Histochemical study revealed that goblet cells in the jejunum of Syrian golden hamsters, unlike those of other experimental animals, produced and released highly sulfated mucins.

Antiviral activity of natural and semi-synthetic chromone alkaloids

The activity against human immunodeficiency virus (HIV) and herpes simplex virus (HSV), of the non-polar fraction of a methanolic extract of the rootbark of Schumanniophyton magnificum was found to be present in a fraction containing the chromone secondary amine schumannificine 1. Other chromone alkaloids present in the plant were isolated and tested for inhibition of HIV and HSV infections in C8166 and Vero cells, respectively. Acyl and methyl derivatives were prepared and tested. Of all the compounds tested, schumannificine 1 displayed the greatest activity against HIV, whereas potent anti-HSV activity was observed for a number of its derivatives. The presence of a piperidine ring and unsubstituted hydroxy groups on the molecules seems to favour the anti-HIV activity. The anti-HIV activity is considered to be due to irreversible binding to gp120 rather than inhibition of reverse transcriptase or protease.

Strongyloides venezuelensis infection in Syrian golden hamster, Mesocricetus auratus, with reference to the phenotype of intestinal mucosal mast cells

Syrian golden hamster, Mesocricetus auratus, was found to be a moderately susceptible host for the intestinal helminth, Strongyloides venezuelensis. After infection by subcutaneous inoculation with 3000 infective larvae (L3), about 20% of them became adult worms in the small intestine, and, after a stable infection up to day 20, adult worms were slowly and gradually expelled towards day 45. Before infection, mast cells in the jejunum were about 30/10 villus crypt units and over 80% of them were formalin-resistant and berberine sulphate-fluorescence positive. After infection with S. venezuelensis, the number of intestinal mast cells gradually increased with time and about a half of them were formalin-sensitive and berberine sulphate fluorescence-negative. Intraepithelial migration of mast cells was never seen before and after infection. Heterogeneity of mucosal mast cells in terms of granular proteoglycans was further confirmed by the determination of critical electrolyte concentration. In spite of the heterogeneity of proteoglycans, enzyme-histochemical study revealed that practically all mucosal mast cells of Syrian golden hamsters were positive for chymase but negative for tryptase. Mast cells in the skin and tongue were also positive for chymase but negative for tryptase. Together with our previous study on mucosal mast cells of other rodents, phenotypic variances of mucosal mast cells seem to be closely related to the protective capacity against the genus Strongyloides.

Selective effector mechanisms for the expulsion of intestinal helminths

In the middle of the era of molecular biology, much less attention is paid to in vivo phenomena. However, carefully designed experimental systems in vivo still can provide valuable information as to the mechanisms underlying the establishment and maintenance of host-parasite relationships. In this review we describe the advantage of using concurrent infections with appropriately chosen combinations of different genera or different maturation stages of parasites to segregate the cellular responses of the host. By means of simple experimental approaches we have found that mucosal mast cells and goblet cells, both of which have long been considered as non-specific effectors, are in fact highly selective and specific effector cells of the host defence mechanisms capable of acting on the establishment and the expulsion of intestinal helminths.

Defective mucosal immunity and normal systemic immunity of Mongolian gerbils, Meriones unguiculatus, to reinfection with Strongyloides venezuelensis

The systemic and local protective activity of Mongolian gerbils was examined after re-infection with Strongyloides venezuelensis. Mongolian gerbils were unable to expel S. venezuelensis adult worms from the intestine for over ten weeks after a primary infection. Therefore, immune animals were prepared by treating with mebendazole four weeks after a primary infection and then they were challenged by different maturation stages of the parasite; subcutaneous inoculation with the infective larvae (L3) obtained by faecal culture, oral administration of L3 obtained from the lungs of rats three days after a primary infection, or oral implantation of adult worms obtained from the intestines of rats seven days after a primary infection. The results show that, although immune animals were highly resistant against challenge infection by subcutaneous inoculation with cultured L3, they were unable to expel orally administered lung-recovered L3 nor orally implanted adult worms. Although potentiated mastocytosis was induced by challenge infections with lung-recovered L3 and adult worms, all mast cells were formalin-resistant, heparin-containing cells and never seen in the epithelial layer. In spite of the defective protective capacity at the intestinal mucosa, circulating antibody production specific to S. venezuelensis adult as well as L3 antigen was positive. Therefore, the inability of Mongolian gerbils to expel S. venezuelensis adult worms from the intestine seems to be due to the defects of effector/regulator cells, presumably mast cells, but not due to immune unresponsiveness to parasite antigen.

Mucosal mast cells and the expulsive mechanisms of mice against Strongyloides venezuelensis

The possible importance of mucosal mast cells in the expulsive mechanisms of mice against Strongyloides venezuelensis was examined. After a primary infection by subcutaneous inoculation with various doses into C57BL/6 mice, about 50% of the initial dose of infective larvae (L3) became adult worms and, regardless of the dose of infection, they were completely expelled by Day 12 with similar kinetics. Intestinal mastocytosis at the time of expulsion was comparable among groups given different doses of infection. A kinetic study after infection with 2000 L3 in C57BL/6 mice revealed that mastocytosis started from Day 8, rapidly reached a peak on Day 12, and then gradually decreased. The strongest mastocytosis was observed in the upper one sixth of the small intestine where the majority of adult worms parasitized. Over 80% of mast cells induced by the infection were located in the intestinal epithelial layer. When mast cell-deficient W/Wv and their normal littermate +/+ mice were infected with 1000 L3, expulsion was significantly delayed in W/Wv mice, though adult worms were eventually expelled by Day 18 in W/Wv mice. Delayed expulsion as well as defective mast cell responses of W/Wv mice were completely restored by bone marrow grafting 10 weeks prior to infection. These results show that, like S. ratti infection, intestinal mucosal mast cells are important in causing expulsion of S. venezuelensis.

Persistent infection of Strongyloides venezuelensis and normal expulsion of Nippostrongylus brasiliensis in Mongolian gerbils, Meriones unguiculatus, with reference to the cellular responses in the intestinal mucosa

The kinetics of daily faecal egg count, worm burdens, and intestinal cellular responses were examined in Mongolian gerbils after infection with either Strongyloides venezuelensis or Nippostrongylus brasiliensis alone, or concurrently with both parasites. The results show that, both in individual and concurrent infections, S. venezuelensis infection persisted for over 10 weeks and elicited a gradual increase in number of mast cells in the jejunal mucosa. On the other hand, N. brasiliensis worms were expelled by 3 weeks in association with goblet cell hyperplasia. These results suggest that effector/regulator cells involved in worm expulsion are different and highly selective depending on the genus of intestinal helminths.

Modification by pertussis toxin of the responses of bovine anterior pituitary cells to acetylcholine and dopamine: effects on hormone secretion and 86Rb efflux

Acetylcholine is known to stimulate the secretion of growth hormone and prolactin and the efflux of 86Rb from bovine anterior pituitary cells: dopamine prevents the stimulation of 86Rb efflux and of prolactin but not growth hormone secretion. The sensitivity of these responses to pertussis toxin has been determined. Treatment of bovine anterior pituitary cells in primary culture with pertussis toxin (18 h, 100 ng/ml) did not modify the stimulation of prolactin secretion by acetylcholine, but prevented its inhibition by dopamine. In lactotrophs, dopamine but not acetylcholine receptors are therefore coupled to secretion through a pertussis toxin substrate. The stimulation of 86Rb efflux by acetylcholine was also unaffected by pertussis toxin and, again, its inhibition by dopamine was prevented. Treatment of the cells with pertussis toxin enhanced the secretion of growth hormone in response to acetylcholine. Nitrendepine (1 mumol/l) prevented the cholinergic stimulation of growth hormone but not prolactin secretion from these cells. Acetylcholine increased the cytoplasmic calcium concentration and this rise was enhanced by treatment of the cells with pertussis toxin. Nitrendepine partially inhibited the rise in calcium caused by acetylcholine, and prevented the enhancement of the rise following pertussis toxin treatment. Cholinergic stimulation of growth hormone therefore depends on calcium entry through nitrendepine-sensitive channels, whereas stimulation of prolactin secretion does not, and in somatotrophs a pertussis toxin substrate may limit calcium entry through these channels. These different sensitivities of somatotrophs and lactotrophs to pertussis toxin and nitrendepine may reflect differences in the properties of the predominant calcium currents in the two cell types.