Impact of Rotaviral Diarrhea on Child Growth in Sub-Saharan Africa and South Asia in the Global Enteric Multicenter Study

Rotavirus is the leading cause of dehydrating diarrhea among children in developing countries. The impact of rotaviral diarrhea on nutritional status is not well understood. We aimed to determine the association between rotavirus-positive moderate-to-severe diarrhea and nutrition in children under 5 years of age. We analyzed data from the Global Enteric Multicenter Study on children 0-59 months old from South Asia and sub-Saharan Africa. The relationships between explanatory variables and outcome variables were assessed using multiple linear regression; the explanatory variable was the presence of rotavirus in the stool sample, and the outcome variables were z scores [length/height-for-age (LAZ/HAZ), weight-for-age (WAZ), and weight-for-length/height (WLZ/WHZ)] at follow-up (∼60 days). The prevalence of rotaviral diarrhea was 17.3% (905/5,219) in South Asia and 19.95% (842/4,220) in sub-Saharan Africa. Rotavirus was associated with higher LAZ/HAZ (β: 0.19; 95% CI: 0.12, 0.26; P <0.001) and WAZ (β: 0.15; 95% CI: 0.79, 0.22; P <0.001) in sub-Saharan Africa and with lower WLZ/WHZ (β coefficient: -0.08; 95% CI: -0.15, -0.009; P = 0.027) in South Asia. Our study indicates that rotaviral diarrhea is positively associated with nutritional status in sub-Saharan Africa and is negatively associated with nutritional status in South Asia. An expedited implementation policy of ongoing preventive and control strategies, including vaccination against rotavirus, is necessary to reduce the burden of rotaviral diarrhea, which may further help to reduce the potential nutritional ramifications.

Changing Water-Sanitation Determinants of Cholera over Two Decades in Bangladesh

Cholera is a leading global public health threat, especially in developing countries. This study aimed to determine the changing determinants of cholera related to water-sanitation practices between 1994-1998 and 2014-2018 in Dhaka, Bangladesh. Data of all cause diarrhea cases were extracted from the Diarrheal Disease Surveillance System of the International Centre for Diarrhoeal Disease Research, Bangladesh, Dhaka, and analysis was performed among three groups: Vibrio cholerae detected as sole pathogen, V. cholerae detected as mixed infection, and detection of no common enteropathogen in stool specimens (reference). Using sanitary toilet, drinking tap water, drinking boiled water, family size greater than five, and slum dwelling were the main exposures. Overall, 3,380 (20.30%) and 1,290 (9.69%) patients were positive for V. cholerae during 1994-1998 and 2014-2018, respectively. In 1994-1998, use of sanitary toilet (adjusted odds ratio [aOR]: 0.86, 95% CI: 0.76-0.97) and drinking tap water (aOR: 0.81, 95% CI: 0.72-0.92) were found to be negatively associated and in 2014-2018, drinking tap water (aOR: 1.47, 95% CI: 1.21-1.78) and slum dwelling (aOR: 1.43, 95% CI: 1.10-1.86) were found to be positively associated with V. cholerae infection after adjusting for age, sex, monthly income, and seasonality. Because the determinants of cholera such as drinking tap water can change over time in developing cities, ameliorating the water, sanitation, and hygiene (WASH) situation is of paramount importance. In addition, in settings such as urban slums, where long-term WASH monitoring might be difficult to achieve, mass vaccination with oral cholera vaccine should be introduced to control cholera.

Symptomatic and Asymptomatic Campylobacter Infections and Child Growth in South Asia: Analyzing Data from the Global Enteric Multicenter Study

Campylobacter is a major cause of food-borne gastrointestinal illnesses worldwide, predominantly affecting children under 5 years of age. This study examined potential associations of symptomatic (with diarrhea) and asymptomatic (without diarrhea) Campylobacter infections with child growth among children under 5 years of age in South Asia. The Global Enteric Multicenter Study was conducted from 2007 to 2011 with a case-control design. Children were followed for 60 days after enrollment. Stool culture was performed to isolate Campylobacter spp. Among the 22,567 enrolled children, 9,439 were symptomatic, with 786 (8.28%) testing positive for Campylobacter. Conversely, 13,128 asymptomatic healthy controls were included, with 1,057 (8.05%) testing positive for Campylobacter. Growth faltering was observed in the symptomatic group, particularly among children aged 0-11 months (-0.19 height-for-age z score [HAZ]; 95% CI: -0.36, -0.03; P = 0.018) and 24-59 months (-0.16 HAZ; 95% CI: -0.28, -0.04; P = 0.010). However, in the asymptomatic group, growth faltering was observed only in the 24- to 59-month age group, in terms of HAZ (-0.15 HAZ; 95% CI: -0.24, -0.05; P = 0.002) and weight-for-height z score (-0.16; 95% CI: -0.26, -0.06; P = 0.001). These findings underscore the importance of immediate and enhanced introduction of preventive modalities to reduce the burden of Campylobacter infections and reduce their long-term sequelae.

Vibrio cholerae in rural and urban Bangladesh, findings from hospital-based surveillance, 2000-2021

With more than 100,000 cases estimated each year, Bangladesh is one of the countries with the highest number of people at risk for cholera. Moreover, Bangladesh is formulating a countrywide cholera-control plan to satisfy the GTFCC (The Global Task Force on Cholera Control) Roadmap's goals. With a particular focus on cholera trends, variance in baseline and clinical characteristics of cholera cases, and trends in antibiotic susceptibility among clinical isolates of Vibrio cholerae, we used data from facility-based surveillance systems from icddr,b's Dhaka, and Matlab Hospitals from years 2000 to 2021. Female patients comprised 3,553 (43%) in urban and 1,099 (51.6%) in rural sites. Of the cases and most patients 5,236 (63.7%) in urban and 1,208 (56.7%) in the rural site were aged 15 years and more. More than 50% of the families belonged to the poor and lower-middle-class; in 2009 (24.4%) were in urban and in 1,791 (84.2%) were in rural sites. In the urban site, 2,446 (30%) of households used untreated drinking water, and 702 (9%) of families disposed of waste in their courtyard. In the multiple logistic regression analysis, the risk of cholera has significantly increased due to waste disposal in the courtyard and the boiling of water has a protective effect against cholera. Rotavirus (9.7%) was the most prevalent co-pathogen among the under-5 children in both sites. In urban sites, the percentage of V. cholerae along with co-existing ETEC and Campylobacter is changing in the last 20 years; Campylobacter (8.36%) and Enterotoxigenic Escherichia coli (ETEC) (7.15%) were the second and third most prevalent co-pathogens. Shigella (1.64%) was the second most common co-pathogen in the rural site. Azithromycin susceptibility increased slowly from 265 (8%) in 2006-2010 to 1485 (47.8%) in 2016-2021, and erythromycin susceptibility dropped substantially over 20 years period from 2,155 (98.4%) to 21 (0.9%). Tetracycline susceptibility decreased in the urban site from 2051 (45.9%) to 186 (4.2%) and ciprofloxacin susceptibility decreased from 2,581 (31.6%) to 1,360 (16.6%) until 2015, then increased 1,009 (22.6%) and 1,490 (18.2%) in 2016-2021, respectively. Since 2016, doxycycline showed 902 (100%) susceptibility. Clinicians need access to up-to-date information on antimicrobial susceptibility for treating hospitalized patients. To achieve the WHO-backed objective of eliminating cholera by 2030, the health systems need to be put under a proper surveillance system that may help to improve water and sanitation practices and deploy oral cholera vaccines strategically.

Water, Sanitation, and Hygiene (WASH) Practices and Outreach Services in Settlements for Rohingya Population in Cox's Bazar, Bangladesh, 2018-2021

(1) Background: This study aimed to investigate the existing water, sanitation, and hygiene (WASH) policy and practice of the study population and strengthen the evidence base by documenting changes in the WASH policy and practice over 3 years of the Rohingya refugee humanitarian crisis, Cox's Bazar, Bangladesh. (2) Methods: A cross-sectional surveillance design was followed; the sampling of the study population included the Rohingya refugee population and neighborhood host nationals who required hospitalization soon after seeking care and enrolled into the diarrheal disease surveillance in diarrhea-treatment centers. Throughout the study period of 3 years, a total of 4550 hospitalized individuals constituted the study participants. (3) Results: Among the hospitalized Rohingya refugee population; the use of public tap water increased significantly from 38.5% in year 1 to 91% in year 3. The use of deep tube well water significantly changed from 31.3% to 8.2%, and the use of shallow tube well water reduced significantly from 25.8% to 0.4%. Households using water seal latrine were 13.3% in year 1 and increased significantly to 31.7% in year 3. ORS consumption at home changed significantly from 61.5% in the first year to 82.1% in third year. Multivariable analysis demonstrated patients' age groups at 5 to 14 years, and 15 years and more, drinking non-tube well water, soap use after using toilet, use of non-sanitary toilet facility, father's and mother's lack of schooling, and some and severe dehydration were significantly associated with the Rohingya refugee population enrolled into the diarrheal disease surveillance. (4) Conclusion: The findings indicate significant advances in WASH service delivery as well as outreach activities by aid agencies for the Rohingya refugee population living in settlements.

Different Features of Cholera in Malnourished and Non-Malnourished Children: Analysis of 20 Years of Surveillance Data from a Large Diarrheal Disease Hospital in Urban Bangladesh

Malnourished children are more prone to infectious diseases including severe diarrhea compared to non-malnourished children. However, data are scarce on differences in the presentation in such children. We aimed to identify clinical differentials among children with cholera with or without malnutrition. Data were extracted from the diarrheal disease surveillance system (DDSS) of Dhaka Hospital of International Centre for Diarrheal Disease Research, Bangladesh (icddr,b) from January 2001 to December 2020. Among children under five in DDSS, cholera positive (culture confirmed) malnourished children (WAZ, WL/HZ or L/HAZ ˂ −2) were considered as cases (n = 920) and children with cholera but non-malnourished (WAZ, WL/HZ or L/HAZ ≥−2.00 to ≤+2.00) were controls (n = 586). After adjusting for potential confounders such as maternal illiteracy, day labor fathers, maternal employment, slum dwelling, non-sanitary latrine use, use of untreated water, and history of cough, it was revealed that malnourished cholera children significantly more often presented in hospital during evening hours (6 p.m. to 12 mid-night) (p < 0.05), had illiterate fathers (p < 0.05), >24 h history of diarrheal duration (p < 0.05), dehydrating diarrhea (p < 0.05), and had longer hospitalization (p < 0.05). The study results underscore the importance of understanding of basic differences in the presentation of severity of cholera in malnourished children for prompt identification and subsequent management of these vulnerable children.

Assessment of anthropogenic-causing-agents act on waterbirds-diversity in the vicinity of Tarbela Dam, Indus River, Pakistan

Birds are among the best bio-indicators, which can guide us to recognize some of the main conservation concerns in ecosystems. Anthropogenic impacts such as deforestation, habitat degradation, modification of landscapes, and decreased quality of habitats are major threats to bird diversity. The present study was designed to detect anthropogenic causative agents that act on waterbird diversity in Tarbella Dam, Indus River, Pakistan. Waterbird censuses were carried out from March 2019 to February 2020 in multiple areas around the dam. A total of 2990 waterbirds representing 63 species were recorded. We detected the highest waterbird richness and diversity at Pehure whereas the highest density was recorded at Kabbal. Human activity impacts seemed to be the main factor determining the waterbird communities as waterbirds were negatively correlated with the greatest anthropogenic impacts. Waterbirds seem to respond rapidly to human disturbance.

Study of human knowledge and attitude toward urban birds in Faisalabad city, Pakistan

Birds are very valuable indicators of species richness and endemic patterns in a specified ecosystem, which eventually help the scientist to measure the environmental degradation. The aim of present study was to know human knowledge and attitude toward urban birds in Faisalabad city, Pakistan. The study conducted in four consecutive months: November 2019 to February 2020. Population of birds was noted from eight residential towns of Faisalabad city, data were collected through questionnaire. Faisalabad has a reasonably large population of birds and present data show that, there is a significant difference between favorite bird of residential areas and institutions. The pigeon received the most likeness in bird population among residential area residents, while the myna received the least. The most popular bird in Faisalabad institutions was the sparrow, while the least popular bird was the common myna. Bird adaptation percentage of residential areas and institutional areas of Faisalabad was the highest for parrot and sparrow respectively. People in residential areas and institutions, on the other hand, adapted least to common myna. It is concluded that people of the study area like birds and offered food and high population of birds are present in study area.

Characteristics of Rotavirus, ETEC, and Vibrio Cholerae Among Under 2-year Children Attending an Urban Diarrheal Disease Hospital in Bangladesh

Background

Information on comparative clinical and host characteristics of under-2 children with watery diarrhea caused by rotavirus, Enterotoxigenic Escherichia coli (ETEC), and Vibrio cholerae as single pathogens is lacking. We sought to investigate the sociodemographic, clinical, and host characteristics of under-2 children hospitalized due to these pathogens.

Methodology

We conducted a hospital-based case-control study using the icddr,b Diarrheal Diseases Surveillance System. Children of either sex, <2 years with diarrhea, who attended the hospital during 2014 to 2018, constituted the study population. Stool specimens having a single pathogen like rotavirus, ETEC, or Vibrio cholerae constituted the cases and stool specimens having no detectable common enteropathogens comprised the controls. Multinomial logistic regression analysis was done where control was the reference group.

Results

A total of 14 889 patients were enrolled, 6939 of whom were under-2 children, and 5245 (76%) constituted our study population. Among them 48% (n = 2532), 3% (n = 148) and 1% (n = 49) had rotavirus, ETEC, and Vibrio cholera, respectively. A control group (diarrhea without these 3 or Shigella, Salmonella, Aeromonas) accounted for 48% (n = 2516). In multinomial regression model, children with rotavirus (adjusted odds ratio [aOR], 1.36; 95% confidence interval [95% CI], 1.19-1.55) less often presented with dehydrating diarrhea compared to those with ETEC (aOR, 1.54; 95% CI, 1.05-2.26) and cholera (aOR, 2.25; 95% CI, 1.11-4.57). Rotavirus diarrhea was associated (aOR, 1.25; 95% CI, 1.07-1.46) with those who received antimicrobials prior to hospital admission and protectively associated with drinking tap water (aOR, 0.84; 95% CI, 0.73-0.95); however, ETEC diarrhea had protective association (aOR, 0.62; 95% CI, 0.43-0.92) with children who received antimicrobials prior to hospital admission and was associated with drinking tap water (aOR, 1.78; 95% CI, 1.19-2.66). Use of intravenous fluid was associated with cholera (aOR, 10.36; 95% CI, 4.85-22.16) and had protective association with rotavirus episodes (aOR, 0.64; 95% CI, 0.45-0.91).

Conclusions

Clinical presentations and host characteristics of rotavirus, ETEC, and Vibrio cholerae diarrhea differed from each other and the information may be helpful for clinicians for better understanding and proper management of these children.

Cholera outbreak in Forcibly Displaced Myanmar National (FDMN) from a small population segment in Cox's Bazar, Bangladesh, 2019

Background

Bangladesh experienced a sudden, large influx of forcibly displaced persons from Myanmar in August 2017. A cholera outbreak occurred in the displaced population during September-December 2019. This study aims to describe the epidemiologic characteristics of cholera patients who were hospitalized in diarrhea treatment centers (DTCs) and sought care from settlements of Forcibly Displaced Myanmar Nationals (FDMN) as well as host country nationals during the cholera outbreak.

Methods

Diarrhea Treatment Center (DTC) based surveillance was carried out among the FDMN and host population in Teknaf and Leda DTCs hospitalized for cholera during September-December 2019.

Results

During the study period, 147 individuals with cholera were hospitalized. The majority, 72% of patients reported to Leda DTC. Nearly 65% sought care from FDMN settlements. About 47% of the cholera individuals were children less than 5 years old and 42% were aged 15 years and more. Half of the cholera patients were females. FDMN often reported from Camp # 26 (45%), followed by Camp # 24 (36%), and Camp # 27 (12%). Eighty-two percent of the cholera patients reported watery diarrhea. Some or severe dehydration was observed in 65% of cholera individuals. Eighty-one percent of people with cholera received pre-packaged ORS at home. About 88% of FDMN cholera patients reported consumption of public tap water. Pit latrine without water seal was often used by FDMN cholera individuals (78%).

Conclusion

Vigilance for cholera patients by routine surveillance, preparedness, and response readiness for surges and oral cholera vaccination campaigns can alleviate the threats of cholera.

Bangladesh observed a large-scale arrival of forcibly displaced individuals from Myanmar in August 2017. The Bangladesh Government, UN agencies, and international and national non-governmental organizations responded immediately with extensive humanitarian response. However, threats of cholera outbreaks were prevailing. The Government of Bangladesh as lead, with technical support from icddr,b collaborating with international agencies undertook a massive oral cholera vaccination (OCV) campaign immediately as a pre-emptive measure to alleviate threats of the cholera outbreak. Despite that mass OCV campaign, threats of cholera outbreak were existing due to new arrivals of the displaced population with compromised host susceptibility, frequent visits to settlements by Bangladesh nationals without exposure to OCV, and the declining vaccine immunity among OCV recipients as well as an increasing number of cohort children without any exposure to OCV. The population faced a cholera outbreak during September-December 2019. This study aims to describe the characteristics of cholera patients, their care-seeking pattern, camp-wise distribution, source of drinking water, sanitation facility, OCV status, and share the experiences from effective interventions to prevent a cholera outbreak. Vigilance for cholera patients by routine surveillance, preparedness for both preventive and control measures, and response readiness for surges and OCV campaigns can alleviate the threats of cholera.

Vibrio cholerae O139 persists in Dhaka, Bangladesh since 1993

BACKGROUND

After a multi-country Asian outbreak of cholera due to Vibrio cholerae serogroup O139 which started in 1992, it is rarely detected from any country in Asia and has not been detected from patients in Africa.

METHODOLOGY/PRINCIPAL FINDINGS

We extracted surveillance data from the Dhaka and Matlab Hospitals of International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b) to review trends in isolation of Vibrio cholerae O139 in Bangladesh. Data from the Dhaka Hospital is a 2% sample of > 100,000 diarrhoeal patients treated annually. Data from the Matlab Hospital includes all diarrhoeal patients who hail from the villages included in the Matlab Health and Demographic Surveillance System. Vibrio cholerae O139 was first isolated in Dhaka in 1993 and had been isolated every year since then except for a gap between 2005 and 2008. An average of thirteen isolates was detected annually from the Dhaka Hospital during the last ten years, yielding an estimated 650 cases annually at this hospital. During the last ten years, cases due to serogroup O139 represented 0.47% of all cholera cases; the others being due to serogroup O1. No cases with serogroup O139 were identified at Matlab since 2006. Clinical signs and symptoms of cholera due to serogroup O139 were similar to cases due to serogroup O1 though more of the O139 cases were not dehydrated. Most isolates of O139 remained sensitive to tetracycline, ciprofloxacin, and azithromycin, but they became resistant to erythromycin starting in 2009.

CONCLUSIONS/SIGNIFICANCE

Cholera due to Vibrio cholerae serogroup O139 continues to cause typical cholera in Dhaka, Bangladesh.

Changing trends in nutritional status of adolescent females: a cross-sectional study from urban and rural Bangladesh

OBJECTIVES

Malnutrition remains a major problem among adolescents worldwide, but the types of nutritional problem impacting this group are changing significantly. This study aims to describe and analyse the trends in nutritional status and related epidemiological characteristics of 10 to 19 years old adolescent girls over time (2001 to 2018) in Bangladesh.

METHODS

We extracted data from the Diarrhoeal Disease- Surveillance System of the International Centre for Diarrhoeal Disease Research Bangladesh. We performed χ² test for trend to test for statistical significance of the changing trends of undernutrition and overnutrition among the study participants. Multivariable logistic regression model was fit to measure the strength of association, reported as adjusted OR (aOR) and corresponding 95% CIs.

RESULTS

A total of 1224 and 628 adolescent females attended urban and rural treatment facilities, respectively, between 2001 and 2018. The proportion of stunting and thinness decreased substantially, whereas overweight has been observed to increase (1.7% to 7.4%, p<0.001) over the study period. Factors independently associated with stunting were illiteracy (aOR 2.39, 95% CI (1.68 to 3.39), p<0.001), monthly family income of less than US$100 (aOR 1.54, 95% CI (1.25 to 1.9), p<0.001) and family belonging to poorest wealth quintile (aOR 1.45, 95% CI (1.13 to 1.87), p=0.004). Younger participants (aOR 2.69, 95% CI (2.10 to 3.45), p<0.001), rural participants (aOR 1.71 95% CI (1.23 to 2.38), p<0.001), longer hospital stay (aOR 1.52, 95% CI (1.16 to 1.98), p=0.002) and monthly family income less than US$100 (aOR 1.44, 95% CI (1.09 to 1.89), p=0.009) were significantly associated with thinness. Conversely, overweight/obesity was associated with monthly family income more than US$100, duration of diarrhoea and rural participants.

CONCLUSION

Undernutrition in adolescent girls has decreased with time, but the burden of overweight has increased. Higher literacy and better wealth status were found to be associated with the improved nutritional status of the participants.

Gender disparity in care-seeking behaviours and treatment outcomes for dehydrating diarrhoea among under-5 children admitted to a diarrhoeal disease hospital in Bangladesh: an analysis of hospital-based surveillance data

INTRODUCTION

Despite economic development and augmented literacy rates, Bangladeshi households are still discriminating against girls when it comes to seeking medical care. We examined gender disparities in diarrhoeal disease severity and the treatment outcomes of under-5 children.

SETTING

A tertiary level diarrhoeal disease hospital in Dhaka, Bangladesh.

PARTICIPANTS

13 361 under-5 children admitted to the hospital between January 2008 and December 2017.

OUTCOME VARIABLES AND METHODS

The primary outcome of interest was severity of diarrhoea, defined as 'dehydrating diarrhoea' or 'non-dehydrating diarrhoea'. Multivariable logistic regression analyses were performed to assess the association between 'gender' and admission to hospital for dehydrating diarrhoea.

RESULTS

Data on 13 321 children under 5 years of age were analysed, of whom 61.5% were male and 38.5% were female. The mean (±SD) age of children with diarrhoea was 5.63 (±3.49) months. The median distance travelled to come to the hospital for admission was 10 miles (IQR: 6-25) and was significantly higher for boys (10 miles, IQR: 6-25) than girls (9.5 miles, IQR: 6-23) (p<0.001). Girls had 1.11 times higher odds (adjusted OR: 1.11, 95% CI 1.03 to 1.20, p=0.007) of presenting with dehydrating diarrhoea than boys at the time of hospital admission. Almost 20% of children received two or more medications during the period of hospital admission and this did not differ by gender. The median duration of hospital stay was 11 hours and was similar in both sexes. No gender-based disparity was observed in the management of diarrhoea and in the hospital outcome of children.

CONCLUSION

We found that girls were more likely to have dehydrating diarrhoea when they were presented to the Dhaka hospital of International Centre for Diarrhoeal Disease Research, Bangladesh. No gender-based disparity was observed in the hospital outcome of children.

Diarrhoeal children with concurrent severe wasting and stunting compared to severe wasting or severe stunting

OBJECTIVE

Children with both severe wasting and severe stunting (SWSS) represent an extreme form of malnutrition and are prone to develop severe infection. The study aims to demonstrate clinical features and aetiology of diarrhoea among children with SWSS compared to those with either severe wasting (SW) or severe stunting (SS), which may help in early identification of high-risk children.

METHODS

Data were extracted from the database of the diarrhoeal disease surveillance system (DDSS) of Dhaka Hospital, icddr,b from 2008 to 2017. Among 14 403 under-five diarrhoeal children, 149 had concurrent SWSS (WLZ/WHZ ˂-3 with LAZ/HAZ ˂-3), 795 had SW (WLZ/WHZ ˂-3 but LAZ/HAZ ≥-3) alone, and 1000 had only SS (LAZ/HAZ ˂-3 but WLZ/WHZ ≥-3).

RESULTS

In logistic regression analysis after adjusting for potential confounders, dehydrating diarrhoea and slum dwelling were independently associated with SWSS vs. SW (P < 0.05). When compared with SS, dehydration and maternal illiteracy were independently associated with SWSS (P < 0.05). In comparison with SW or SS, SWSS less often included infection with rotavirus (P < 0.05). Dehydration was independently associated with SW vs. SS after adjusting for potential confounders (P < 0.05).

CONCLUSION

Children with SWSS more often presented with dehydrating diarrhoea (69%) than children who had either SW (55%) or SS (43%). However, SWSS patients less frequently presented with rotavirus-associated diarrhoeal illnesses. This result underscores the importance of early detection and prompt management of dehydrating diarrhoea in children with concomitant severe wasting and severe stunting to reduce morbidity and mortality in these children, especially in poor settings.

Changing Susceptibility Pattern of Vibrio cholerae O1 Isolates to Commonly Used Antibiotics in the Largest Diarrheal Disease Hospital in Bangladesh during 2000-2018

The efficacy of commonly used antibiotics for treating severe cholera has been compromised over time because of the reduced antibiotic susceptibility. This study aimed to describe the rate of detection of Vibrio cholerae O1 from fecal samples and antimicrobial susceptibility profiles of V. cholerae O1 serotypes to commonly used antibiotics. During January 2000-December 2018, V. cholerae O1 was detected in fecal samples of 7,472 patients. Vibrio cholerae O1 Inaba serotype was predominant, ranging from 60% to 86% during the period 2000-2006 except for 2003 and 2005 when the Ogawa serotype was predominant. Later on, the Ogawa serotype became predominant from 2007 to 2015, fluctuating between 52% and 100%. However, in 2016 and 2017, isolation rates declined to 2% and 1%, respectively, but surged again to 75% in 2018. Nearly 100% of V. cholerae O1 strains were sensitive to tetracycline during 2000-2004. Thereafter, a declining trend of sensitivity was observed to be continued and dropped down to < 6% during 2012-2017 and again increased to 76% in 2018. Susceptibility to azithromycin and ciprofloxacin was nearly 100%, and susceptibility to cotrimoxazole and furazolidone was 01% throughout the study period. We also found the emergence of resistance to erythromycin in 2005 and sensitivity to cotrimoxazole in 2018. Thus, the rapid decline of the sensitivity of V. cholerae O1 to tetracycline and a reversed peak after 6 years need continued monitoring and reporting.

Pathogen-specific risk of seizure in children with moderate-to-severe diarrhoea: Case control study with follow-up

OBJECTIVE

To determine the pathogen-specific risk of seizure in under-five children hospitalised with moderate-to-severe diarrhoea (MSD) in rural settings.

METHOD

This was a prospective case-control study with follow-up, conducted in a sentinel facility of Global Enteric Multicenter Study in Mirzapur, a rural community of Bangladesh between 2007 and 2010. Children aged 0-59 months who presented with MSD and seizure constituted the cases whereas those who did not have seizure comprised the controls. MSD was defined if the episodes were associated with dehydration or dysentery or required hospitalisation with diarrhoea or dysentery. All enrolled children were followed up at home within 50-90 days of enrolment. A total of 64 cases and 128 randomly selected controls formed the analysable dataset.

RESULTS

The result of logistic regression analysis after adjusting for potential confounders revealed that shigellosis (Shigella species, OR = 5.34, 95% CI = 2.37-12.04) particularly S. flexneri (OR = 3.34, 95% CI = 1.48-7.57), S. flexneri 6 (OR = 23.24, 95% CI = 2.79-193.85), S. sonnei (OR = 6.90, 95% CI = 2.34-19.85); norovirus (OR = 6.77, 95% CI = 1.69-27.11), fever (OR = 16.75, 95% CI = 1.81-154.70) and loss of consciousness (OR = 35.25, 95% CI = 1.71-726.20) were the independent risk factors for seizure in MSD children. At enrolment, cases had lower WHZ (P = 0.006) compared to their peers, follow-up anthropometrics showed significant improvement in WHZ (P < 0.001) and WAZ (P < 0.05), whereas deterioration in HAZ (P < 0.001) in both cases and controls.

CONCLUSION

Childhood MSD episodes particularly due to Shigella and norovirus are often associated with seizure. Prompt identification and appropriate management of children with shigellosis may reduce occurrence and adverse consequences of seizure linked with MSD.

Viral Pathogen-Specific Clinical and Demographic Characteristics of Children with Moderate-to-Severe Diarrhea in Rural Bangladesh

Diarrheal disease is a leading cause of childhood morbidity and mortality worldwide, but particularly in low-income countries in sub-Saharan Africa and South Asia. The Global Enteric Multicenter Study (GEMS) examined the infectious etiologies as well as associated demographics, socioeconomic markers, health-care-seeking behaviors, and handwashing practices of the households of children with diarrhea and their age- and gender-matched controls in seven countries over a 3-year period (December 2007-December 2010). Stool studies to determine diarrheal etiologies and anthropometry were performed at baseline and at 60-day follow-up visits, along with surveys to record demographics and living conditions of the children. We performed secondary analyses of the GEMS data derived from the Bangladesh portion of the study in children with diarrhea associated with viral enteropathogens and explored pathogen-specific features of disease burden. Rotavirus and norovirus were the most prevalent pathogens (39.3% and 35%, respectively). Disease due to rotavirus and adenovirus was more common in infants than in older children (P < 0.001 and P = 0.001, respectively). Height for age decreased from baseline to follow-up in children with diarrhea associated with rotavirus, norovirus, and adenovirus (P < 0.001). Based on these analyses, preventive measures targeted at rotavirus, norovirus, and adenovirus will be expected to have meaningful clinical impact. Cost of treatment was highest for rotavirus as well, making it an obvious target for intervention. Association of specific viruses with stunting is particularly notable, as stunting is an attributable risk factor for poor cognitive development and future productivity and economic potential.

Comparison of Outcome of Eclamptic Patient Following Vaginal Delivery versus Caeserian Delivery by Spinal Anaesthesia

Eclampsia is a common problem in pregnancy in Bangladesh. It is a severe form of preeclampsia which affects 5 to 7% of pregnancies is a significant cause of maternal & neonatal morbidity & mortality. Pre-eclampsia when complicated with generalized tonic-clonic convulsions and/or coma is called eclampsia. The term eclampsia is derived from a Greek word, meaning "like a flash of lightening". It may occur quite abruptly, without any warning manifestations. Eclampsia is a major cause of maternal mortality & morbidity as well as foetal loss worldwide, particularly in the third world. Appropriate measures & effective treatment of eclamptic patient in proper time reduce maternal mortality & morbidity. The mainstay of treatment of eclampsia is delivery of the foetus. Two methods are usually applied for delivery of foetus in eclampsia i.e. vaginal delivery & caesarean delivery. This study was done in the department of Gynae & Obs and department of Anaesthesiology, Mymensingh Medical College Hospital from 1st January 2016 to 30th June 2016 to observe the incidence, complications (morbidity) & mortality of eclamptic patients & which method (vaginal delivery versus caesarean delivery by spinal anaesthesia) is safe, better for the eclamptic patients as well as foetal mortality. Successful vaginal delivery is dependant on complex interactions of three variables (3 P) that is power (uterine contraction), passenger (foetus) & passage (birth canal) but power is less effective in eclamptic patient than normal partuents. Vaginal delivery requires prolong times compared with cesarean delivery. Anaesthetic technique is also an important factor for maternal mortality & morbidity of caesarean delivery. Spinal anaesthesia is widely regarded as a reasonable anaesthetic option for caesarean delivery in eclamptic patients. Currently the safety of spinal anaesthesia is well established and it can provide better obstetrical outcome when chosen properly. In this observation caesarean delivery by spinal anesthesia is safer, less complications, less maternal & neonatal mortality than vaginal delivery in eclamptic patients.

Study of Prostatic Volume and its Variations in Different Age Groups of Bangladeshi Cadaver

Benign prostatic hyperplasia and carcinoma of the prostate are the most common disorders of Bangladeshi male in recent years. Volume of the prostate is necessary to estimate the amount of BPH adenoma to determine the appropriate therapy or to select the surgical approach. Transurethral resection of prostate (TURP) is preferred for small glands and open prostatectomy for larger ones. Decrease in prostatic mass after hormonal manipulation or radiation therapy can be used as an indicator of therapeutic efficacy. The effect of prostate volume on biopsy outcome was assessed and was noted that there was an inverse relationship in between size of the gland and prostate cancer. A cross sectional descriptive study was conducted in Department of Anatomy, Mymensingh Medical College, Mymensingh, Bangladesh to find out the difference in volume of the prostate gland of Bangladeshi people in relation to age. The present study was performed on 67 postmortem human prostate gland collected from the morgue in the Department of Forensic Medicine, Mymensingh Medical College by non random purposive sampling technique. The specimens were collected from Bangladeshi cadaver of age ranging from 10 to 80 years. All the specimens were grouped into three categories: Group A (upto 18 years), Group B (19 to 45 years) and Group C (above 45 years) according to age. Dissection was performed according to standard autopsy techniques. The volume of the prostate gland were measured and recorded. The mean volume of the prostate gland was 13.75ml in Group A, 24.44ml in Group B and 29.72ml in Group C. Variance analysis shows that mean differences of volume of the prostate were highly significant among all age groups. The volume of prostate gland was found to be increased with increasing age. For statistical analysis, differences between age groups were analyzed by using students unpaired 't' test. The present study will help to increase the information pool on the volume of prostate gland of Bangladeshi people.

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.

Ambras Syndrome: First Reported Case in Bangladesh and its Oral Rehabilitation

People with rare hypertrichosis syndromes became crowd-drawing money-making phenomena in many 19th century sideshow acts. These individuals have been referred to as dog-men, hair-men, and werewolves. In 1993, Baumister et al. described congenital hypertrichosis lanuginose or Ambras syndrome: a distinct form of congenital hypertrichosis characterized by excessive hair growth over the body and face associated with facial and occasional dental anomalies. Much is not known about this syndrome since fewer than 50 cases have been documented worldwide. In this case report, a nine year old girl presented with excessive hair growth throughout her body that was denser along her midline. Furthermore, her face displayed the typical dysmorphic features characteristic of Ambras syndrome: a round tip nose, thickened nasal cartilage, antiverted nares, prominent philtrum with deep groove, and a trapezoid mouth. Oral examination revealed normal oral mucosa with completely missing and unerupted decidious and permanent teeth. Panoramic radiographs confirmed unerupted deciduous teeth. Previous case reports have mentioned the presence of occasional dental anomalies such as retarded first and second dentition and absence of some teeth. However, this is the first reported case of Ambras syndrome presenting with complete anodontia. Prior cytogenetic studies performed on persons with Ambras syndrome have implicated a balanced pericentric inversion of chromosome 8. However, it is likely that dental anomalies are likely a result of a different genetic rearrangement. Further studies are needed to explore the cause of this rare phenotype of Ambras syndrome with complete unerupted dentition.

Health care-seeking behavior for childhood diarrhea in Mirzapur, rural Bangladesh

We evaluated patterns of health care use for diarrhea among children 0–59 months of age residing in Mirzapur, Bangladesh, using a baseline survey conducted during May–June 2007 to inform the design of a planned diarrheal etiology case/control study. Caretakers of 7.4% of 1,128 children reported a diarrheal illness in the preceding 14 days; among 95 children with diarrhea, 24.2% had blood in the stool, 12.2% received oral rehydration solution, 27.6% received homemade fluids, and none received zinc at home. Caretakers of 87.9% sought care outside the home; 49.9% from a pharmacy, and 22.1% from a hospital or health center. The primary reasons for not seeking care were maternal perception that the illness was not serious enough (74.0%) and the high cost of treatment (21.9%). To improve management of childhood diarrhea in Mirzapur, Bangladesh, it will be important to address knowledge gaps in caretakers' assessment of illness severity, appropriate home management, and when to seek care in the formal sector. In addition, consideration should be given to inclusion of the diverse care-giving settings in clinical training activities for diarrheal disease management.

Frequency of impaired glucose tolerance and diabetes mellitus in subjects with fasting blood glucose below 6.1 mmol/L (110 mg/dL)

The diagnosis of diabetes mellitus by the available criteria is controversial and relies heavily on fasting glucose results. This cross-sectional study in 2010-2011 aimed to measure the frequency of impaired glucose tolerance and diabetes mellitus in 127 subjects having fasting blood glucose < 7.0 mmol/L and to measure the agreement between different standard diagnostic criteria. Subjects presenting to a laboratory for analysis of fasting blood glucose for excluding diabetes mellitus underwent a 2-hour 75 g oral glucose challenge. A total of 40.6% of subjects with fasting blood glucose from 5.6-6.0 mmol/L had abnormal glucose regulation on the basis ofthe gold standard glucose challenge. Agreement between American Diabetes Association and World Health Organization diagnostic criteria was only fair (kappa = 0.32). Abnormalities of glucose metabolism including impaired glucose tolerance and diabetes mellitus can exist at fasting blood glucose results < 6.1 mmol/L (110 mg/dL).

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.

Role of the androgen receptor CAG repeat polymorphism in prostate cancer, and spinal and bulbar muscular atrophy

Androgens are involved in the development of several tissues, including prostate, skeletal muscle, bone marrow, hair follicles, and brain. Most of the biological effects of the androgens are mediated through an intracellular transcription factor, the androgen receptor (AR) at the level of gene regulation. Several types of mutations in the AR gene have been linked to endocrine dysfunctions. The expansion of CAG codon repeat, coding for a polyglutamine (PolyQ) tract in the N-terminal domain is one such mutation. The polyQ chain length impacts AR's ability to interact with critical coregulators, which in turn modulates its transcriptional efficacy. Pathologic manifestations of variations in polyQ chain length have been associated with prostate cancer susceptibility, and the Spinal and Bulbar Muscular Atrophy (SBMA), a neurodegenerative disease. In this review article, we discuss multiple aspects of the role of polyQ chain length in the actions of the AR, their importance in prostate cancer development and progression, and SBMA with an aim to understand the underlying mechanisms involved in these diseases, which can be targeted for future therapeutic approaches.

Radiology reporting: a general practitioner's perspective

Unlike hospital-based clinicians, general practitioners (GPs) lack direct contact with radiologists, and the radiology report is usually the sole method of communication from the radiologist to the GP. It is important to gain feedback regarding what GPs perceive as a good-quality radiology report, especially in the current climate of competition for provision of radiology services. The aims of this study are to determine the level of GP satisfaction with radiology reports, their perception of optimum report content and their preferences regarding the level of detail and report format. A questionnaire was sent to 100 GPs referring to our Trust for radiology services. GPs were generally satisfied with the content and clarity of reports that they receive, and gave suggestions on how reports could be improved. The majority of GPs were unfamiliar with the normal size ranges of frequently measured anatomical structures. Radiologists' recommendations for further treatment, referral and non-radiological investigation were viewed as valuable report components. When asked to rank preferences for ultrasound reports for the same patient with differing formats and levels of detail, GPs favoured detailed reports in a tabulated format. In conclusion, the majority of GPs like detailed reports and value the radiologist's opinion outside the remit of imaging when suggesting further patient management. Reporting the size of a structure without explanation of its significance can potentially cause confusion. It is important to know if GPs are satisfied with the radiology reports they receive so that we can uphold high communication standards and ultimately improve patient care.

Upper lip swelling caused by a large dentigerous cyst with mesiodens

Swelling of upper lip can results from various diseases such as salivary tumors, infections and inflammatory diseases and cyst, typically involving unerrupted teeth, are sometimes associated with supernumerary teeth in the maxillary anterior incisor region called the mesiodens. Mesiodens with dentigerous cyst is actually a rare case in the world and of course in Bangladesh. The overall prevalence of this type of cyst is only 0.15-1.9% of the total population. Recently we have experienced this kind of case like dentigerous cyst with mesiodens in the department of dentistry, Bangladesh Institute of Research and Rehabilitation in Diabetes, Endocrine and Metabolic Disorders (BIRDEM) Hospital. The patient was 24 years old male young complaining of slow growing painless swelling on the upper lip region for the last several years. Clinical examination revealed a soft intra oral swelling in the labial surface of maxillary incisor region and there was also extra orally upper lip swelling. Radiographic examination demonstrated a large radiolucent area with a mesiodens extending to the root of both lateral incisors. The patient was treated surgically by enucleation of total cysts and surgical extraction of mesiodens under local anesthesia.

Effects of different osmolytes on the induced folding of the N-terminal activation domain (AF1) of the glucocorticoid receptor

In order to understand gene regulation by glucocorticoids, it is pivotal to know how the major transactivation domain AF1 of the glucocorticoid receptor (GR) functions. Located in the N-terminal region of the GR, AF1 is quantitatively important for transcriptional regulation, but only in recent years have we begun to understand how AF1 works. This is in part due to the fact that the recombinant AF1 (rAF1) peptide exists as a random ensemble of conformers. Algorithms that predict structure support the view that AF1 is also not well ordered in the holo-GR, and the properties of the amino acids in AF1 suggest that it is intrinsically disordered. However, it is generally believed that intrinsically disordered sequences of the GR AF1 must achieve one or more ordered conformation(s) to carry out transactivation activity. Based on our previous published work and available literature, we hypothesize that a confluence of effects that operate under physiological conditions cause functionally active conformation(s) to form in AF1. We have shown that when rAF1 is incubated in increasing concentrations of a naturally occurring osmolyte trimethylamine-N-oxide (TMAO), the peptide folds into functionally active conformation(s) that selectively binds several critical coregulatory proteins. Because cells contain various organic osmolytes whose effects may be cumulative, and in light of cell-specific effects of GR AF1 action, we tested whether it can be folded by other natural organic osmolytes representative of three classes: certain amino acids (proline), methylamines (sarcosine), and polyols (sorbitol). The osmolyte-induced folding of rAF1 shows greatly increased affinity for specific binding proteins, including TATA box-binding protein (TBP), CREB-binding protein (CBP), and steroid receptor coactivator-1 (SRC-1). Consistent with theory and published data with other proteins, our results show that different osmolytes have differential effects on rAF1 folding. The cell-specific functions of the GR AF1--and by extension the AF1s of other nuclear hormone receptors--may in part be affected by the presence and concentrations of particular osmolytes within a particular cellular environment.

Pattern of local relapse of maxillary sinus carcinoma

Maxillary sinus carcinoma (MSC) is a rare disease with a variety of treatment options. The present study was undertaken to review the outcome of patients with treated MSC in order to clarify the factors related to local recurrence by analyzing CT findings. The study group comprised of 47 cases, 40 males and 7 females with a median age of 61 years (range, 40- 84 years) treated between 1988 to 1996 at the department of radiotherapy. CT was taken with a slice thickness of 5 mm and contrast material was routinely used. The mean follow-up period for the group was 45.0 months (range, 3-125 months). The treatment policy was either preoperative radiotherapy of 40Gy/16fr followed by maxillectomy or radical radiotherapy of 65Gy/26fr with partial maxillectomy during the course of radiotherapy. By using CT-simulation, wedge pair techniques were used in most patients with Cobalt or 6MV X-ray machines as treatment sources. Tumor extension was categorized into the following anatomical sites: orbital contents, other paranasal sinuses, posterior wall of the maxillary sinus, pterygoid plate/muscle, nasopharynx, infra-temporal fossa, base of the skull, anterior wall of the maxillary sinus, subcutaneous tissue, cheek mucosa, hard palate and alveolar bone. Local control was computed by using the Kaplan-Meier method and p value was measured by using Chi-squared test. The 5-year overall local control rates for all patients were 56%. The local recurrence was found in 19 of 47 patients (40.4%). Tumors extending to pterygoid plates (n=13) and pterygoid muscles (n=10) showed higher rate of local recurrences as compared to those without extensions (9/13 [69%] vs 10/34 [29%], p<0.02 and 7/10 [70%] vs 12/37 [32%], p<0.05, respectively). Extensions to nasopharynx (6/9, 66%) and base of skull (4/6, 66%) also showed higher rates of recurrence; however, those were not statistically significant. More than 80% of the relapse became manifest within 12 months of diagnosis and isolated local failure was the most common pattern. This analysis indicates that tumor extension to pterygoid plate/muscles, results in higher rates of recurrences. This may due to the difficult surgical accessibility of the tumor. During radiotherapy planning, special emphasis should be given to this sites of tumor extension to avoid possible local recurrence.

Expression of FGFR-2 and FGFR-3 in the normal human fetal orbit

AIMS

To demonstrate the expression patterns of two fibroblast growth factor receptors (FGFR-2 and FGFR-3) in the normal human fetal orbit.

METHODS

6 microm orbital slide sections were prepared from 12 week old human fetal material obtained within established ethical guidelines. Radioactive in situ hybridisation techniques were used to demonstrate the expression patterns of FGFR-2 and FGFR-3 within these sections. Only one foetus had appropriate orbital sections taken.

RESULTS

FGFR-2 was expressed within the extraocular muscles (EOMs) and the optic nerve sheath and to a lesser degree within the orbital periosteal margins and the cranial sutures. FGFR-3 was expressed a lot within the periosteal margins and cranial sutures but not within either the EOMs or the optic nerve sheath.

CONCLUSIONS

FGFR-2 and FGFR-3 are differentially expressed within different orbital components. FGFR-2 gene mutations may be responsible for craniosynostotic syndromes such as Crouzon, Pfeiffer, and Apert, while those in the FGFR-3 gene may cause isolated unicoronal synostosis. EOMs may be histologically abnormal in cases of Apert, Pfeiffer, and Crouzon syndromes but not isolated unicoronal synostosis. The pattern of expression of FGFR-2 in the normal human fetal orbit may explain some of the EOM histological findings seen in some cases of Apert, Pfeiffer, and Crouzon syndromes.

Antiischemic effects of topiramate in a transient global forebrain ischemia model: a neurochemical, histological, and behavioral evaluation

The mechanisms of action of the anticonvulsant topiramate (TPM) are indicative of a potential benefit during cerebral ischemia. TPM was studied in a transient global forebrain ischemia (TGFI) model in gerbils in which 40 mg/kg was administered before or after TGFI. Control groups were administered 0.9% normal saline similarly. The evaluation consisted of neurochemical, histological, and functional analyses. The data obtained indicates that unlike the focal cerebral ischemia model, TPM is not neuroprotective in TGFI. The difference in effect, which may be due to the difference in species or the type of ischemia, points to the need for caution when extrapolating animal data from this drug to humans.

Visual outcomes and amblyogenic risk factors in craniosynostotic syndromes: a review of 141 cases

AIMS

To determine the visual outcome and prevalence of amblyogenic risk factors in children with craniosynostotic syndromes.

METHODS

The case notes of 141 children seen within the craniofacial unit were reviewed and information retrieved on date of birth, age at first and last examination, cycloplegic refraction at last visit, best corrected visual acuity at last visit, horizontal ocular deviation in primary position at first visit, and alphabet pattern if any. The presence of astigmatism, its magnitude, and orientation of axis were determined.

RESULTS

40.3% of patients had 1 dioptre (D) of astigmatism or greater and, of these, 64% had oblique astigmatism in at least one eye. Anisometropia of 1D or more was found in 18% of patients (age matched normals 3.5%). Horizontal strabismus was found in 70% (38% exotropia, 32% esotropia). Visual outcome results showed 39.8% of patients (45 of 113) had visual acuity of 6/12 or worse in their better eye.

CONCLUSION

In the largest study to date a poor visual outcome was shown in children with Crouzon's, Pfeiffer's, Apert's, and Saethre-Chotzen syndromes (39.8% with 6/12 or worse in the better eye) together with significant prevalence of amblyogenic risk factors.

The technique of intracerebral microdialysis

Intracerebral microdialysis is an increasingly popular experimental technique. A brief description of the principles of microdialysis is presented and the terms relevant to the procedure are defined. The methodology involved in conducting intracerebral microdialysis is described in detail. Factors influencing the outcome of analysis such as external stimuli, perfusion fluid, perfusion rate, temperature, probe placement, membrane characteristics, and timing of sample collection are discussed. The importance of maintaining the uniformity of the above-mentioned factors is stressed.

Mechanisms involved in the potentiation of melphalan by the bioreductive compound THNLA-1 in vitro

9-[3-(2-Nitro-1-imidazolyl)propylamino]-1,2,3,4-tetrahydroacridine hydrochloride (THNLA-1) is a 2-nitroimidazole-based, weakly DNA-intercalating bioreductive agent that significantly potentiates the toxic effects of commonly used antitumor drugs such as melphalan (L-PAM) or cis-DDP in sensitive or resistant cell lines in culture, as well as in solid tumors in mice. Potentiation in vitro was observed when cells were preexposed to THNLA-1 under hypoxic conditions before exposure to L-PAM under aerobic conditions. In this study we investigated possible mechanisms involved in the potentiation of L-PAM by THNLA-1 in V79 Chinese hamster cells. Limited depletion of glutathione with buthionine sulfoximine or THNLA-1 under hypoxic pretreatment conditions accounted for only 8.3% of the potentiation induced by THNLA-1. However, DNA, RNA, and protein synthesis were inhibited in a synergistic way in cells preexposed to THNLA-1 under hypoxic conditions (2 h, 37 degrees C) and then coexposed to various doses of L-PAM under aerobic conditions (1 h, 37 degrees C). Cell cycle analysis by flow cytometry showed a slow traverse through the S phase in the L-PAM-alone-treated cells. However, this phenomenon was more prominent in the THNLA-1 plus L-PAM-treated cells. Under aerobic co-incubation conditions with L-PAM, no difference was observed in the cell cycle of L-PAM-alone-treated cells vs. THNLA-1 plus L-PAM-treated cells. Significantly increased apoptosis was observed in the hypoxia-pretreated cells with THNLA-1, 12 and 24 h posttreatment. Comet and alkaline elution assay analysis showed increased DNA cross-links in the hypoxia-pretreated cells with THNLA-1 compared to the L-PAM-alone-treated cells. Finally, potential lethal damage repair was totally suppressed only in the hypoxia-pretreated cells with THNLA-1. In conclusion, DNA damage and hindrance in its repair are the most important mechanisms in the potentiation of L-PAM by THNLA-1, under hypoxic pretreatment conditions.

Tibial plateau fractures. A new classification scheme

Fractures of the tibial plateaus are common injuries. Various classification schemes have been used to describe these injuries. Although each system has its own purpose, the simpler systems do not allow comparison with more complex divisions. The problem is compounded by the variable use of adjectives that describe these fractures. A comprehensive classification of tibial plateau fractures should group fractures that are similar in topography, morphology, and pathogenesis, requiring similar treatment, and having a similar prognosis. Fracture dislocations and standard tibial plateau fractures should be incorporated into a single classification to avoid the use of two complementary classifications. Any such classification should not be difficult to remember or to use. Keeping in mind these requirements, the authors devised a simple yet comprehensive classification. The authors studied 80 cases of tibial plateau fractures from January 1988 to September 1997, and used contemporary classifications of tibial plateau fractures as a database to formulate the new classification. A new fracture, subcondylar bicondylar with coronal split, has been classified for the first time. An alphanumeric system has been developed that has made nomenclature easy to remember and use. An effort has been made to address the profoundly confusing issue of variable adjectives that describe these injuries. A review of the literature shows that fractures in the authors' classification have been grouped according to similar pathomechanics, treatment, and functional results.

Evaluation of an optimal temperature for brain storage in delayed 2, 3,5-triphenyltetrazolium chloride staining

This paper presents the determination of an optimal temperature for delayed 2,3,5-triphenyltetrazolium chloride (TTC) staining. Twenty-one rats were subjected to right middle cerebral artery embolic stroke and sacrificed 96 h following ischemia. The brains were harvested and stained immediately after sacrifice or stored for 8 h at 21-23 degrees C or 4 degrees C, respectively. The stained sections were scanned and infarct volume calculated. The quality of staining, distinction of borders between infarcted and non-ischemic tissue and ease of differentiating ischemic tissue in colored and grayscale images was assessed. The present study indicates that results of TTC obtained immediately after animal sacrifice, or delayed TTC staining while storing the brains at room temperature or 4 degrees C are comparable.

Differential requirement for p19ARF in the p53-dependent arrest induced by DNA damage, microtubule disruption, and ribonucleotide depletion

p19ARF has been implicated as a key regulator of p53 stability and activation. While numerous stresses activate the p53 growth arrest pathway, those requiring p19ARF remain to be elucidated. We used p19ARF knockout mouse embryo fibroblasts to show that DNA damage and microtubule disruption require p19ARF to induce p53 responses, whereas ribonucleotide depletion and inhibition of RNA synthesis by low doses of actinomycin D do not. The data provide evidence that the arrest pathway activated by ribonucleotide depletion involves some different signal transducers than those activated by DNA damage or microtubule disruption. We also present biochemical analyses that provide insights into the mechanism by which p53 and p19ARF cooperate in normal cells to induce cell cycle arrest.

The role of taurine in neuronal protection following transient global forebrain ischemia

Osmoregulation and post ischemic glutamate surge suppression (PIGSS) are important mechanisms in the neuroprotective properties of taurine. We studied the role of taurine in PIGSS following transient global forebrain ischemia (TGFI). A group of gerbils received a high dose of continuous intracerebral taurine during the peri-ischemic period. Beta-alanine was given similarly to a negative control group. The control group consisted of animals undergoing only TGFI. On the fourth day following commencement of drug administration, TGFI was induced. Concurrently, half the animals from each group receiving an agent had intracerebral microdialysis. All animals underwent histological assessment at day 7. The microdialysis and histological data was analyzed. Our results showed that taurine treatment did not cause PIGSS. The histological difference between the three groups was statistically insignificant. We conclude that intracerebral taurine in the dosage administered during peri-ischemic period, does not result in PIGSS or histologically evident neuroprotection.

Evidence that Watermelon Leaf Curl Disease in Pakistan Is Associated with Tomato Leaf Curl Virus-India, a Bipartite Begomovirus

Whitefly-transmitted geminiviruses (begomoviruses) have emerged as major constraints on food and fiber crops worldwide, and there are several examples of begomovirus mobilization in previously unknown host plants. Here we report on evidence that leaf curl disease of watermelon in Pakistan is caused by Tomato leaf curl virus-India (TLCV-India). Leaf curl disease of watermelon, characterized by leaf curling and mottling and stunted plant growth, was observed at several locations in the Punjab Province of Pakistan. Symptomatic and asymptomatic leaf samples were collected from three locations, and total DNA was isolated by the cetyltrimethylammoniumbromide method and resolved in agarose gel. A full-length clone of Cotton leaf curl virus DNA A was labeled with ^[32P]dCTP and used as a general probe in Southern hybridization. The probe detected characteristic geminivirus DNA forms in infected watermelon plants, whereas no signal was detected in asymptomatic plants. The association of a begomovirus was confirmed further by polymerase chain reaction (PCR) amplification with degenerate primers PAL1V and pAR1c (2). Samples were screened for infection by TLCV-India, because of symptom similarity. A full-length clone of DNA B of TLCV-India (1) was labeled with ^[32P]dCTP by random priming and was used as a specific probe in Southern hybridization. The probe detected geminivirus DNA forms, showing that the disease is associated with TLCV-India. Primers TLCV1 (GAGGTACCAAAACTTGTCGTTTTGATTCGG), in the virion-sense, and TLCV2 (GCCCATGGTTCTTTGCTCGGAGAACAAGAA), in the complementary-sense, were designed based on the sequence of DNA A of TLCV-India. These primers were used in PCR and amplified a product of the expected size from infected plants. Similarly, primers TLCVBC1 (GCGGATCCTTATTCCGTAATTATATCTGCA), in the virion-sense, and TLCV BC2 (CACCATGGCAATAGGAAATGATGGTATGGG), in the complementary-sense, were designed based on the sequence of DNA B of TLCV-India (1). These primers amplified a product of expected size when used in PCR. The results show that watermelon leaf curl disease in Pakistan is associated with TLCV-India. This the first report of detection of a begomovirus in watermelon in Pakistan and the first report of detection of TLCV-India on a plant other than tomato from Southeast Asia. References: (1) M. Padidam et al. J. Gen. Virol. 76:25, 1995. (2) M. R. Rojas et al. Plant Dis. 77:340, 1993.

Association of a Begomovirus and Nanovirus-like Molecule with Ageratum Yellow Vein Disease in Pakistan

Whitefly-transmitted geminiviruses (begomoviruses) cause heavy losses to many food and fiber crops in Pakistan. Many weeds also show symptoms typical of begomoviruses. Ageratum (Ageratum conyzoides) is a common perennial weed in Pakistan, growing along irrigation canals, that often shows symptoms, such as yellow vein and mosaic, suggesting infection by a begomovirus. To confirm this, symptomatic and asymptomatic ageratum plants were collected from three locations in the Punjab Province of Pakistan, and total DNA was isolated, subjected to agarose gel electrophoresis, transferred to a nylon membrane, and Southern blotted. Total DNA isolated from cotton infected with Cotton leaf curl virus (CLCuV), tomato infected with Tomato leaf curl virus from Pakistan (TLCV-Pak), tobacco infected with African cassava mosaic virus (ACMV) from Nigeria, and healthy tobacco were included as controls. A full-length clone of CLCuV DNA A was labeled with ^[32P]dCTP by oligo-labeling and hybridized at medium stringency. The probe detected characteristic geminivirus DNA forms in symptomatic ageratum and plants infected with CLCuV, TLCV-Pak, and ACMV, while no signal was detected in asymptomatic ageratum from the field or healthy tobacco. To confirm infection by a begomovirus, degenerate primers WTGF (5'-GATTGTACGCGTCCDCCTTTAATTT GAAYBGG-3'), designed in the rep gene of begomoviruses, and WTGR (5'-TANACGCGTGGC TTCKRTACATGGCCTDT-3'), designed in the coat protein gene of DNA A of begomoviruses, were used in polymerase chain reaction (PCR). Degenerate primers (PBLv2040 and PCRc1) also were used in PCR (2). A product of expected size (≈1.4 kb) was obtained with DNA A primers from symptomatic ageratum, while no product was obtained with DNA B primers in the same sample. Previously we were unable to detect a DNA component equivalent to begomovirus DNA B in cotton showing symptoms of cotton leaf curl disease (1). We recently reported a novel circular DNA molecule that was approximately half as long as the full-length DNA A (CLCuV DNA-1) associated with CLCuV that share homology to plant nanoviruses (1). The supercoiled replicative form of viral DNA isolated from infected ageratum plants indicated the presence of smaller molecules, as was found in cotton leaf curl disease, suggesting that a nanovirus-like molecule might be associated with ageratum yellow vein disease. A duplicate blot of samples used in Southern hybridization with the DNA A probe was prepared, and a probe of the full-length clone of the nanovirus-like molecule (CLCuV DNA-1) was prepared as described for DNA A. The probe detected characteristic nanovirus DNA forms in ageratum with yellow vein symptoms and cotton infected with CLCuV, while no signal was detected in plants infected with TLCV-Pak or ACMV, healthy tobacco, or asymptomatic ageratum. Abutting primers PB2-F and PB2R (1), designed based on the CLCuV DNA-1 sequence, were unable to amplify a PCR product from ageratum with yellow vein symptoms, suggesting the nanovirus-like molecule associated with ageratum yellow vein disease is distinct from CLCuV DNA-1. Our results show that yellow vein disease of ageratum in Pakistan is associated with a begomovirus infection and single-stranded circular DNA molecule with similarity to CLCuV DNA-1. References: (1) S. Mansoor et al. Virology 259:190, 1999. (2) M. R. Rojas et al., Plant Dis. 77:340, 1993.

p53 regulation by post-translational modification and nuclear retention in response to diverse stresses

p53 activation by diverse stresses involves post-translational modifications that alter its structure and result in its nuclear accumulation. We will discuss several unresolved topics regarding p53 regulation which are currently under investigation. DNA damage is perhaps the best-studied stress which activates p53, and recent data implicate phosphorylation at N-terminal serine residues as critical in this process. We discuss recent data regarding the potential kinases which modify p53 and the possible role of the resulting phosphorylation events. By contrast, much less is understood about agents which disrupt the mitotic spindle. The cell cycle phase, induction signal, and biochemical mechanism of the reversible arrest induced by microtubule disruption are currently under investigation. Finally, a key event in response to any genotoxic stress is the accumulation of p53 in the nucleus. The factors which determine the steady state level of p53 are starting to be elucidated, but the mechanisms responsible for nuclear accumulation and nuclear export remain controversial. We discuss new studies revealing a mechanism for nuclear retention of p53, and the potential contributions of MDM2 to this process.

Identification of a novel circular single-stranded DNA associated with cotton leaf curl disease in Pakistan

Recent reports have suggested that cotton leaf curl virus (CLCuV), a geminivirus of the genus Begomovirus, may be responsible for cotton leaf curl disease in Pakistan. However, the causal agent of the disease remains unclear as CLCuV genomic components resembling begomovirus DNA A are unable to induce typical disease symptoms when reintroduced into plants. All attempts to isolate a genomic component equivalent to begomovirus DNA B have been unsuccessful. Here, we describe the isolation and characterisation of a novel circular single-stranded (ss) DNA associated with naturally infected cotton plants. In addition to a component resembling DNA A, purified geminate particles contain a smaller unrelated ssDNA that we refer to as DNA 1. DNA 1 was cloned from double-stranded replicative form of the viral DNA isolated from infected cotton plants. Blot hybridisation using probes specific for either CLCuV DNA or DNA 1 was used to demonstrate that both DNAs co-infect naturally infected cotton plants from different geographical locations. DNA 1 was detected in viruliferous Bemisia tabaci and in tobacco plants infected under laboratory conditions using B. tabaci, indicating that it is transmitted by whiteflies. Sequence analysis showed that DNA 1 is approximately half the size of CLCuV DNA but shares no homology, indicating that it is not a defective geminivirus component. DNA 1 has some homology to a genomic component of members of Nanoviridae, a family of DNA viruses that are normally transmitted by aphids or planthoppers. DNA 1 encodes a homologue of the nanovirus replication-associated protein (Rep) and has the capacity to autonomously replicate in tobacco. The data suggest that a nanovirus-like DNA has become whitefly-transmissible as a result of its association with a geminivirus and that cotton leaf curl disease may result from a mutually dependent relationship that has developed between members of two distinct DNA virus families that share a similar replication strategy.