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Find video protocols related to scientific articles indexed in Pubmed.
Biomonitoring of ochratoxin A in blood plasma and exposure assessment of adult students in Bangladesh.
Mol Nutr Food Res
PUBLISHED: 09-23-2014
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Ochratoxin A (OTA), a mycotoxin known for its nephrotoxic, immunotoxic, and carcinogenic effects in animals, deserves attention due to its widespread occurrence as food and feed contaminant. Studies in many countries report the presence of OTA in human blood plasma or serum at variable levels. However, no biomonitoring study has been carried out in so far, and also food analysis data are insufficient to assess OTA exposure.
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Differences in lineage replacement dynamics of G1 and G2 rotavirus strains versus G9 strain over a period of 22years in Bangladesh.
Infect. Genet. Evol.
PUBLISHED: 08-29-2014
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Group A rotaviruses (RVAs) have been a major cause of severe gastroenteritis in Bangladesh, mainly in children below the age of five. At the icddr,b, RVA strains collection and characterization dates back for more than 20years. This sample collection was used to study the molecular evolution of the VP7 gene of G1, G2 and G9 RVA strains, which have been circulating in Bangladesh for most of this study period. The evolutionary rates (95% HPD) for G1, G2 and G9 were calculated to be 0.93×10(-)(3) (0.68-1.18), 1.45×10(-)(3) (1.12-1.78) and 1.07×10(-)(3) (0.78-1.39), respectively, which is in line with previous data for the RVA VP7 outer capsid protein, which is under strong negative selective pressure. Bayesian analyses revealed that for the G1 and G2 genotypes, one or multiple lineages co-circulated for one or a few seasons, frequently followed by replacement with genetically different lineages. This can be explained by the existence of a large variety of G1 and G2 RVA lineages and the rapid dissemination of different lineages across the globe. In contrast, circulating G9 lineages were rather closely related to each other across the study period and they were usually derived from variants circulating in the previous season(s). This is consistent with the fact that G9 RVAs have circulated in the human population for less than 20years, and therefore their genetic diversity is much smaller, not resulting in the replacement of circulating G9 strains by highly divergent G9 lineages from abroad. Such different evolutionary dynamics for different RVA genotypes may alter their response to the selective pressure that might be exerted by the introduction of RVA vaccines and therefore a continued close monitoring is warranted.
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Community-based management of acute malnutrition in Bangladesh: feasibility and constraints.
Food Nutr Bull
PUBLISHED: 08-01-2014
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To achieve the United Nations Millennium Development Goals, particularly reduction in child mortality (Millennium Development Goal 4), effective interventions to address severe and moderate acute malnutrition (SAM and MAM) among children under 5 years of age must be implemented and brought to scale alongside preventive measures. Bangladesh has an estimated 600,000 children with SAM, for a prevalence of 4%, while 1.8 million children suffer from MAM.
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A duplex recombinant viral nucleoprotein microbead immunoassay for simultaneous detection of seroresponses to human respiratory syncytial virus and metapneumovirus infections.
J. Virol. Methods
PUBLISHED: 01-24-2014
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Serologic diagnosis of human respiratory syncytial virus (hRSV) and human metapneumovirus (hMPV) infections has been shown to complement virus detection methods in epidemiologic studies. Enzyme immunoassays (EIAs) using cultured virus lysate antigens are often used to diagnose infection by demonstration of a ?4-fold rises in antibody titer between acute and convalescent serum pairs. In this study, hRSV and hMPV nucleocapsid (recN) proteins were expressed in a baculovirus system and their performance compared with virus culture lysate antigen in EIAs using paired serum specimens collected from symptomatic children. The recN proteins were also used to develop a duplex assay based on the Luminex microbead-based suspension array technology, where diagnostic rises in antibody levels could be determined simultaneously at a single serum dilution. Antibody levels measured by the recN and viral lysate EIAs correlated moderately (hRSV, r(2)=0.72; hMPV, r(2)=0.76); the recN EIAs identified correctly 35 of 37 (94.6%) and 48 of 50 (96%) serum pairs showing diagnostic antibody rises by viral lysate EIAs. Purified recN proteins were then coupled to microbeads and serum pairs were tested at a single dilution on a Luminex MAGPIX(®) analyzer. The duplex recN assay identified correctly 33 of 39 (85%) and 41 of 47 (86.7%) serum pairs showing diagnostic rises to hRSV and hMPV, respectively. The recN assay permits simultaneous testing for acute hRSV and hMPV infections and offers a platform for expanded multiplexing of other respiratory virus assays.
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High-Frequency Rugose Exopolysaccharide Production by Vibrio cholerae Strains Isolated in Haiti.
PLoS ONE
PUBLISHED: 01-01-2014
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In October, 2010, epidemic cholera was reported for the first time in Haiti in over 100 years. Establishment of cholera endemicity in Haiti will be dependent in large part on the continued presence of toxigenic V. cholerae O1 in aquatic reservoirs. The rugose phenotype of V. cholerae, characterized by exopolysaccharide production that confers resistance to environmental stress, is a potential contributor to environmental persistence. Using a microbiologic medium promoting high-frequency conversion of smooth to rugose (S-R) phenotype, 80 (46.5%) of 172 V. cholerae strains isolated from clinical and environmental sources in Haiti were able to convert to a rugose phenotype. Toxigenic V. cholerae O1 strains isolated at the beginning of the epidemic (2010) were significantly less likely to shift to a rugose phenotype than clinical strains isolated in 2012/2013, or environmental strains. Frequency of rugose conversion was influenced by incubation temperature and time. Appearance of the biofilm produced by a Haitian clinical rugose strain (altered biotype El Tor HC16R) differed from that of a typical El Tor rugose strain (N16961R) by confocal microscopy. On whole-genome SNP analysis, there was no phylogenetic clustering of strains showing an ability to shift to a rugose phenotype. Our data confirm the ability of Haitian clinical (and environmental) strains to shift to a protective rugose phenotype, and suggest that factors such as temperature influence the frequency of transition to this phenotype.
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Genital Human Papillomavirus Infection among Women in Bangladesh: Findings from a Population-Based Survey.
PLoS ONE
PUBLISHED: 01-01-2014
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There has been no population-based study on human papillomavirus (HPV) prevalence or its genotypes in Bangladesh; a country eligible for GAVI funding for HPV vaccine.
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Surrogate production of eggs and sperm by intrapapillary transplantation of germ cells in cytoablated adult fish.
PLoS ONE
PUBLISHED: 01-01-2014
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Germ cell transplantation (GCT) is a promising assisted reproductive technology for the conservation and propagation of endangered and valuable genetic resources. In teleost fish, GCT in adult gonads has been achieved only in male recipients, limiting greatly the usefulness of this technique in situations where both sexes need equal and timely attention for conservation and/or propagation. Here we describe a simplified GCT approach that ultimately leads to production of donor-derived eggs and sperm in considerably short time. Donor germ cells isolated from young pejerrey Odontesthes bonariensis (Atherinopsidae) were transplanted non-surgically through the genital papilla into the sexually mature gonads of Patagonian pejerrey O. hatcheri recipients whose gonads have been depleted of endogenous GCs by heat (26°C) and chemical treatment (four doses of Busulfan at 30 mg/kg and 40 mg/kg for females and males, respectively). Transplanted spermatogonial and oogonial cells were able to recolonize the recipients' gonads and produce functional donor origin eggs and sperm within 7 months from the GCT. We confirmed the presence of donor-derived gametes by PCR in 17% and 5% of the surrogate O. hatcheri fathers and mothers, respectively. The crosses between surrogate fathers and O. bonariensis mothers yielded 12.6-39.7% pure O. bonariensis and that between a surrogate mother and an O. bonariensis father yielded 52.2% pure O. bonariensis offspring. Our findings confirm that transplantation of germ cells into sexually competent adult fish by non-surgical methods allows the production of functional donor-derived eggs and sperm in a considerably short time. The methods described here could play a vital role in conservation and rapid propagation of endangered fish genetic resources.
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Vibrio cholerae persisted in microcosm for 700 days inhibits motility but promotes biofilm formation in nutrient-poor lake water microcosms.
PLoS ONE
PUBLISHED: 01-01-2014
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Toxigenic Vibrio cholerae, ubiquitous in aquatic environments, is responsible for cholera; humans can become infected after consuming food and/or water contaminated with the bacterium. The underlying basis of persistence of V. cholerae in the aquatic environment remains poorly understood despite decades of research. We recently described a "persister" phenotype of V. cholerae that survived in nutrient-poor "filter sterilized" lake water (FSLW) in excess of 700-days. Previous reports suggest that microorganisms can assume a growth advantage in stationary phase (GASP) phenotype in response to long-term survival during stationary phase of growth. Here we report a V. cholerae GASP phenotype (GASP-700D) that appeared to result from 700 day-old persister cells stored in glycerol broth at -80°C. The GASP-700D, compared to its wild-type N16961, was defective in motility, produced increased biofilm that was independent of vps (p<0.005) and resistant to oxidative stress when grown specifically in FSLW (p<0.005). We propose that V. cholerae GASP-700D represents cell populations that may better fit and adapt to stressful survival conditions while serving as a critical link in the cycle of cholera transmission.
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Population-based incidence of severe acute respiratory virus infections among children aged <5 years in rural Bangladesh, June-October 2010.
PLoS ONE
PUBLISHED: 01-01-2014
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Better understanding the etiology-specific incidence of severe acute respiratory infections (SARIs) in resource-poor, rural settings will help further develop and prioritize prevention strategies. To address this gap in knowledge, we conducted a longitudinal study to estimate the incidence of SARIs among children in rural Bangladesh.
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Efficacy of oseltamivir treatment started within 5 days of symptom onset to reduce influenza illness duration and virus shedding in an urban setting in Bangladesh: a randomised placebo-controlled trial.
Lancet Infect Dis
PUBLISHED: 11-22-2013
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Influenza causes substantial morbidity and mortality worldwide. Few data exist for the efficacy of neuraminidase inhibitors, which are the only readily available influenza treatment options, especially in low-income settings. We assessed the efficacy of treatment with the neuraminidase inhibitor oseltamivir to reduce patient illness and viral shedding in people with influenza, in whom treatment was started within 5 days of symptom onset, in an urban setting in Bangladesh.
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High prevalence of noroviruses among hospitalized diarrheal patients in Bangladesh, 2011.
J Infect Dev Ctries
PUBLISHED: 11-19-2013
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Norovirus is not usually investigated in diarrheal patients in Bangladesh which may account for the many cases where no pathogens are identified.
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An ethnobotanical study of medicinal plants used by tribal and native people of Madhupur forest area, Bangladesh.
J Ethnopharmacol
PUBLISHED: 08-20-2013
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Madhupur forest area, Tangail is one of early human settlements in Bangladesh. Having abode in the vicinity of the forest, a strong ethnobotanical practice has prevailed in this area since ancient time. Due to the rapid deforestation during the last few decades, many plants have already disappeared or are facing extinction. Thus we attempted to document the medicinal plant use of Madhupur forest area with a view to preserve the ethnobotanical knowledge and in order to protect the biodiversity of this area.
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Epidemiology and genetic diversity of human astrovirus infection among hospitalized patients with acute diarrhea in Bangladesh from 2010 to 2012.
J. Clin. Virol.
PUBLISHED: 07-31-2013
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Globally, human astroviruses (HAstVs) have emerged as another common cause of non-bacterial acute gastroenteritis. Limited data exist on the epidemiology and genetic diversity of HAstVs in Bangladesh.
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Bis(tert-butylpyrene) nanotweezers and nanocalipers: enhanced extraction and recognition abilities for single-walled carbon nanotubes.
Chemistry
PUBLISHED: 07-17-2013
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We developed a host-guest methodology for separation of single-walled carbon nanotubes (SWNTs) according to the handedness, diameter and metallicity by the use of diporphyrin nanotweezers and nanocalipers. Although the pyrene has been frequently used to replace porphyrin, due to a similar affinity to the surface of SWNTs and better availability, the extraction and recognition abilities of dipyrene nanotweezers were not so good as those of diporphyrin ones as we reported previously. However, introduction of a tert-butyl substituent at the 7-position of 2-pyrene is found to enhance the extraction and recognition abilities of dipyrene nanotweezers and nanocalipers. That is, (6,5)-SWNTs were obtained in high purity by use of bis(tert-butylpyrene) nanotweezers with a phenanthrene spacer and metallic SWNTs were highly enriched by use of bis(tert-butylpyrene) nanocalipers with a carbazole-anthracene-carbazole spacer.
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Novel intergenotype human norovirus recombinant GII.16/GII.3 in Bangladesh.
Infect. Genet. Evol.
PUBLISHED: 06-10-2013
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Noroviruses (NoVs) are one of the major etiological agents of acute gastroenteritis in all age groups. In this study, we identified an intergenotype NoV recombinant strain in the fecal specimens of two male infants with acute diarrhea in Bangladesh. Phylogenetic analysis showed that the identified strains were recombinant NoV strains with a GII.3 capsid and a GII.16 polymerase gene. The recombination breakpoint was located in the ORF1/ORF2 overlap region. To the best of our knowledge this is the first report of a NoV recombinant GII.16/GII.3 strain worldwide.
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Genetic characterization of a rare bovine-like human VP4 mono-reassortant G6P[8] rotavirus strain detected from an infant in Bangladesh.
Infect. Genet. Evol.
PUBLISHED: 06-08-2013
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During an ongoing diarrhea etiology surveillance in Mirzapur, Bangladesh, a rare human G6P[8] RVA strain (RVA/Human-wt/BGD/KH2288/2011/G6P[8]) was detected in a stool sample of a 7-month-old infant with acute diarrhea. Complete genotype analyses revealed that KH2288 possessed the G6-P[8]-I2-R2-C2-M2-A11-N2-T6-E2-H3 genotype constellation. Sequence analysis of the VP7 gene revealed a close phylogenetic relationship with bovine G6 strains from India, whereas, the VP4 gene segment was nearly identical to typical human P[8] strain circulating in Bangladesh and the rest of the world. Phylogenetic analysis of the remaining nine gene segments revealed a close relatedness to either animal or animal derived human RVA strain. We speculated that, strain KH2288 was a monoreassortant between a human RVA strain and a RVA strain typically infecting member of the Artiodactyla, such as cattle, goat or sheep. To our knowledge, this is the first complete genotyping report of a naturally occurring G6P[8] RVA strain, worldwide.
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Clade C HIV-1 isolates circulating in Southern Africa exhibit a greater frequency of dicysteine motif-containing Tat variants than those in Southeast Asia and cause increased neurovirulence.
Retrovirology
PUBLISHED: 05-28-2013
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HIV-1 Clade C (Subtype C; HIV-1C) is responsible for greater than 50% of infections worldwide. Unlike clade B HIV-1 (Subtype B; HIV-1B), which is known to cause HIV associated dementia (HAD) in approximately 15% to 30% of the infected individuals, HIV-1C has been linked with lower prevalence of HAD (0 to 6%) in India and Ethiopia. However, recent studies report a higher prevalence of HAD in South Africa, Zambia and Botswana, where HIV-1C infections predominate. Therefore, we examined whether Southern African HIV-1C is genetically distinct and investigated its neurovirulence. HIV-1 Tat protein is a viral determinant of neurocognitive dysfunction. Therefore, we focused our study on the variations seen in tat gene and its contribution to HIV associated neuropathogenesis.
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Etiological diversity of diarrhoeal disease in Bangladesh.
J Infect Dev Ctries
PUBLISHED: 05-11-2013
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This study compared the diversity of common diarrhoeal pathogens and antimicrobial susceptibility in four hospitals in Bangladesh.
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Investigating a crow die-off in January-February 2011 during the introduction of a new clade of highly pathogenic avian influenza virus H5N1 into Bangladesh.
Arch. Virol.
PUBLISHED: 04-15-2013
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We investigated unusual crow mortality in Bangladesh during January-February 2011 at two sites. Crows of two species, Corvus splendens and C. macrorhynchos, were found sick and dead during the outbreaks. In selected crow roosts, morbidity was ~1 % and mortality was ~4 % during the investigation. Highly pathogenic avian influenza virus H5N1 clade 2.3.2.1 was isolated from dead crows. All isolates were closely related to A/duck/India/02CA10/2011 (H5N1) with 99.8 % and A/crow/Bangladesh/11rs1984-15/2011 (H5N1) virus with 99 % nucleotide sequence identity in their HA genes. The phylogenetic cluster of Bangladesh viruses suggested a common ancestor with viruses found in poultry from India, Myanmar and Nepal. Histopathological changes and immunohistochemistry staining in brain, pancreas, liver, heart, kidney, bursa of Fabricius, rectum, and cloaca were consistent with influenza virus infection. Through our limited investigation in domesticated birds near the crow roosts, we did not identify any samples that tested positive for influenza virus A/H5N1. However, environmental samples collected from live-bird markets near an outbreak site during the month of the outbreaks tested very weakly positive for influenza virus A/H5N1 in clade 2.3.2.1-specific rRT-PCR. Continuation of surveillance in wild and domestic birds may identify evolution of new avian influenza virus and associated public-health risks.
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Comparative study of serum zinc, copper, manganese, and iron in preeclamptic pregnant women.
Biol Trace Elem Res
PUBLISHED: 04-06-2013
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Preeclampsia complicates 2-8 % of all pregnancies and it is one of the leading causes of maternal mortality and pre-term delivery in the world. Unfortunately, there is scarcity of document discussing the circulating level of several essential trace elements in preeclampsia patients in Bangladesh. The present study was designed to evaluate the serum concentration of four trace elements, namely zinc, copper, manganese, and iron, in preeclamptic pregnant women. The study was conducted as a case-control study with 50 preeclamptic pregnant women as cases and 58 normotensive pregnant women as controls. Obstetric, anthropometric, and clinical data were collected at routine obstetric visits. Serum trace elements were determined by flame atomic absorption spectroscopy. Independent sample t test and Pearsons correlation test were done for the statistical analysis using the statistical software package SPSS, version 16.0 (SPSS Inc., Chicago, IL). We observed significant differences for gestational age, body mass index, and systolic and diastolic blood pressure between patient and control groups (p??0.05) except the correlation between zinc and iron in preeclampsia patients (p?
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Comparative analysis of serum zinc, copper, manganese, iron, calcium, and magnesium level and complexity of interelement relations in generalized anxiety disorder patients.
Biol Trace Elem Res
PUBLISHED: 03-05-2013
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The purpose of the study was to determine the concentration of serum trace and other essential elements of generalized anxiety disorder patients and to find out the relationship between element levels and nutritional status or socioeconomic factors. The study was conducted among 50 generalized anxiety disorder patients and 51 healthy volunteers. Patients were selected and recruited in the study with the help of a clinical psychologist by random sampling. The concentrations of serum trace elements (Zn, Cu, Mn, and Fe) and other two essential elements (Ca and Mg) were determined by graphite furnace and flame atomic absorption spectroscopy. Data were analyzed by independent t test, Pearsons correlation analysis, regression analysis, and analysis of variance. The serum concentrations of Zn, Cu, Mn, Fe, Ca, and Mg in generalized anxiety disorder patients were 1.069?±?0.40, 1.738?±?0.544, 1.374?±?0.750, 3.203?±?2.065, 108.65?±?54.455, and 21?±?4.055 mg/L, while those were 1.292?±?0.621, 0.972?±?0.427, 0.704?±?0.527, 1.605?±?1.1855, 101.849?±?17.713, and 21.521?±?3.659 mg/L in control subjects. Significantly decreased (p??0.05). Socioeconomic data revealed that most of the patients were in the lower middle class group and middle-aged. Mean BMI of the control group (23.63?±?3.91 kg/m(2)) and the patient group (23.62?±?3.77 kg/m(2)) was within the normal range (18.5-25.0 kg/m(2)). The data obtained from different interelement relations in the generalized anxiety disorder patients and control group strongly suggest that there is a disturbance in the element homeostasis. So changes in the serum trace element level in generalized anxiety disorder patients occur independently and they may provide a prognostic tool for the diagnosis and treatment of this disease.
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A novel norovirus recombinant strain GII.4/GII.21 in Bangladesh, 2011.
Virus Genes
PUBLISHED: 02-19-2013
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We identified a novel inter-genotype recombinant norovirus strain, Dhaka85/2011/BGD, collected from a stool specimen of a nine-month-old infant who was hospitalized with diarrhea. Molecular investigation and phylogenetic analysis classified its RNA polymerase gene as GII.4-like, which commonly circulates in humans. The capsid gene was classified as GII.21-like, most likely originated from water. The discovery of this novel strain is an illustration of the enormous diversity among the norovirus strains, especially in developing countries and has important implications for future vaccine strategies.
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Changing profile of rotavirus genotypes in Bangladesh, 2006-2012.
BMC Infect. Dis.
PUBLISHED: 02-17-2013
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Rotavirus is the leading cause of severe diarrhea in infants and young children worldwide including Bangladesh. Unlike what was seen in high-income countries, the licensed rotavirus vaccines did not show high efficacy in Bangladeshi trials. We assessed rotavirus prevalence and genotypes in Bangladesh over six-year period to provide baseline information on the rotavirus burden and changing profile in the country.
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Challenges to evaluating respiratory syncytial virus mortality in Bangladesh, 2004-2008.
PLoS ONE
PUBLISHED: 01-24-2013
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Acute lower respiratory illness is the most common cause of death among children, globally. Data are not available to make accurate estimates on the global mortality from respiratory syncytial virus (RSV), specifically.
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Molecular Dating of HIV-1 Subtype C from Bangladesh.
PLoS ONE
PUBLISHED: 01-01-2013
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Bangladesh has an overall low HIV prevalence of <0.1% in the general population and <1% among key affected populations, but it is one of few Asian countries that has yet to reverse the epidemic. In order to do this, it is important to understand the transmission dynamics in this country. The aim of this study was to investigate the phylogenetic relationships of HIV-1 subtype C strains from Bangladesh and related strains from other countries, and thereby clarify when and from where subtype C was introduced in the country and how it subsequently spread within Bangladesh. The phylogenetic analysis included 118 Bangladeshi gag sequences and 128 sequences from other countries and was performed using the BEAST package. Our analysis revealed that the vast majority of Bangladeshi sequences (97/118, 82%) fall into a large regional cluster of samples from Bangladesh, India, China and Myanmar, which dates back to the early 1960s. Following its establishment in the region, this strain has entered Bangladesh multiple times from around 1975 and onwards, but extensive in-country transmission could only be detected among drug users and not through sexual transmission. In addition, there have been multiple (at least ten) introductions of subtype C to Bangladesh from outside this region, but no extensive spread could be detected for any of these. Since many HIV-infections remain undetected while asymptomatic, the true extent of the transmission of each strain remains unknown, especially among hard to reach groups such as clients of sex workers and returning migrants with families.
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Molecular characterization of hepatitis B virus strains circulating in Belgian patients co-infected with HIV and HBV: overt and occult infection.
J. Med. Virol.
PUBLISHED: 09-15-2011
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Hepatitis B virus (HBV) and human immunodeficiency virus (HIV) have similar transmission routes, implying that patients infected with HIV are at particular risk for HBV infection. Patients who are co-infected with HIV and HBV progress more rapidly to end-stage liver disease and different HBV genotypes may have a distinct impact on disease progression. One hundred ninety-one anti-HBc-positive sera from Belgian patients co-infected with HIV and HBV were collected during 1998-2008. Full-length HBV genomes as well as large S or partial S genes were amplified and their molecular evolutionary history was analyzed. Clinically, 30 (65.8%) patients were categorized as "overt infection" and 16 (34.7%) cases were categorized as "occult infection." Five distinct HBV genotypes comprising A (69.6%), E (19.6%), followed by D, C, and G were detected. HBV genotype A was observed in all clinical groups and in patients with varying ethnical background. HBV genotype E could be detected in African patients who were mostly infected by heterosexual contacts. Several clinically important mutations at the HBs major hydrophilic region were detected in the new isolates but with no significant difference between occult and overt infection. The high prevalence of HBV genotype A in overt and occult cases, and in particular the detection of certain HBV subgenotypes in patients co-infected with HIV and HBV that carry diagnostic escape mutations, may provide useful information for national guidelines for prophylaxis and treatment.
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Co-circulation of G1, G2 and G9 rotaviruses in hospitalized patients in Bangladesh during 2006-2009.
Hum Vaccin
PUBLISHED: 09-01-2011
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Rotavirus strain diversity in Bangladesh has been explored since 1985 and as seen in other parts of the world, rotaviruses have shown tremendous strain diversity overtime. Rotavirus antigen was detected in stool specimens using a solid-phase sandwich-type enzyme immunoassay. A multiplex reverse transcription polymerase chain reaction (RT-PCR) was performed for rotavirus G and P genotypes. This current study was carried out between 2006 and 2009 during which time 1,607 (23%) of 7,058 fecal specimens tested positive for group A rotaviruses with the highest incidence rate being observed in winter each year. Genotyping of rotaviruses showed a sharp decline in G2P[4] between 2008 and 2009 with a gradual increase in G1 and G9 strains. Since the Government of Bangladesh is planning to include rotavirus vaccine in the national immunization program, these data on rotavirus strain diversity should be taken into consideration for vaccine strain selection.
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Improved selectivity in discriminating handedness and diameter of single-walled carbon nanotubes with N-substituted 3,6-carbazolylene-bridged chiral diporphyrin nanotweezers.
Nanoscale
PUBLISHED: 06-15-2011
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Chiral diporphyrin nanotweezers 1 consisting of two chiral porphyrins with N-substituted 3,6-carbazolylene in between have been studied for the separation of single-walled carbon nanotubes (SWNTs). As compared to the analogous nanotweezers 2 without an N-substitutent, nanotweezers 1 with the N-octylcarbazolylene spacer exhibit much higher extraction ability and better selectivity for SWNTs. A narrower diameter range of SWNTs, from 0.88 to 0.92 nm, was selectively extracted with nanotweezers 1. In addition, only (7,6)-SWNTs of 0.90 nm diameter were optically enriched through extraction with 1, while SWNTs extracted with 2 showed lower optical purity of (7,6)-SWNTs. These enhanced extraction and discrimination abilities of 1 can be attributed to the formation of a more stable SWNT complex of 1 than of 2 in methanol.
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Epidemiology of rotavirus and cholera in children aged less than five years in rural Bangladesh.
J Health Popul Nutr
PUBLISHED: 05-03-2011
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Despite the known presence of rotavirus-associated diarrhoea in Bangladesh, its prevalence, including records of hospitalization in rural health facilities, is largely unknown. In a systematic surveillance undertaken in two government-run rural health facilities, 457 children, aged less than five years, having acute watery diarrhoea, were studied between August 2005 and July 2007 to determine the prevalence of rotavirus. Due to limited financial support, the surveillance of rotavirus was included as an addendum to an ongoing study for cholera in the same area. Rotavirus infection was detected in 114 (25%) and Vibrio cholerae in 63 (14%) children. Neither rotavirus nor V cholerae was detected in 280 (61%) samples; these were termed non-rotavirus and non-cholera diarrhoea. Both rotavirus and cholera were detected in all groups of patients (<5 years). The highest proportion (41%; 47/114) of rotavirus was in the age-group of 6-11 months. In children aged less than 18 months, the proportion (67%; 76/114) of rotavirus was significantly (p < 0.001) higher than that of cholera (16%; 10/63). By contrast, the proportion (84%; 53/63) of cholera was significantly (p < 0.001) higher than that of rotavirus (33%; 38/114) in the age-group of 18-59 months. During the study period, 528 children were hospitalized for various illnesses. Thirty-eight percent (202/528) of the hospitalizations were due to acute watery diarrhoea, and 62% were due to non-diarrhoeal illnesses. Rotavirus accounted for 34% of hospitalizations due to diarrhoea. Severe dehydration was detected in 16% (74/457) of the children. The proportion (51%; 32/63) of severe dehydration among V cholerae-infected children was significantly higher (p < 0.001) compared to the proportion (16%; 18/114) of rotavirus-infected children. The study revealed that 12-14% of the hospitalizations in rural Bangladesh in this age-group were due to rotavirus infection, which has not been previously documented.
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Uniformity of rotavirus strain nomenclature proposed by the Rotavirus Classification Working Group (RCWG).
Arch. Virol.
PUBLISHED: 02-23-2011
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In April 2008, a nucleotide-sequence-based, complete genome classification system was developed for group A rotaviruses (RVs). This system assigns a specific genotype to each of the 11 genome segments of a particular RV strain according to established nucleotide percent cutoff values. Using this approach, the genome of individual RV strains are given the complete descriptor of Gx-P[x]-Ix-Rx-Cx-Mx-Ax-Nx-Tx-Ex-Hx. The Rotavirus Classification Working Group (RCWG) was formed by scientists in the field to maintain, evaluate and develop the RV genotype classification system, in particular to aid in the designation of new genotypes. Since its conception, the group has ratified 51 new genotypes: as of April 2011, new genotypes for VP7 (G20-G27), VP4 (P[28]-P[35]), VP6 (I12-I16), VP1 (R5-R9), VP2 (C6-C9), VP3 (M7-M8), NSP1 (A15-A16), NSP2 (N6-N9), NSP3 (T8-T12), NSP4 (E12-E14) and NSP5/6 (H7-H11) have been defined for RV strains recovered from humans, cows, pigs, horses, mice, South American camelids (guanaco), chickens, turkeys, pheasants, bats and a sugar glider. With increasing numbers of complete RV genome sequences becoming available, a standardized RV strain nomenclature system is needed, and the RCWG proposes that individual RV strains are named as follows: RV group/species of origin/country of identification/common name/year of identification/G- and P-type. In collaboration with the National Center for Biotechnology Information (NCBI), the RCWG is also working on developing a RV-specific resource for the deposition of nucleotide sequences. This resource will provide useful information regarding RV strains, including, but not limited to, the individual gene genotypes and epidemiological and clinical information. Together, the proposed nomenclature system and the NCBI RV resource will offer highly useful tools for investigators to search for, retrieve, and analyze the ever-growing volume of RV genomic data.
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Clinical presentation and molecular characterization of group B rotaviruses in diarrhoea patients in Bangladesh.
J. Med. Microbiol.
PUBLISHED: 12-23-2010
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A total of 1106 stool samples collected from diarrhoea patients admitted to Dhaka hospital of the International Centre for Diarrhoeal Disease Research, Bangladesh, during January-December 2008 were analysed for the presence of rotavirus-specific RNA by PAGE. The group B-specific RNA migration pattern was detected in 26 patients (2.4%) and group A-specific pattern in 259 patients (23.4%). Clinical data from group A and group B rotavirus-infected patients indicated that episodes did not differ much in the prevalence of diarrhoea, number of stools, outcome or differences in gender. However, abdominal pain was more common in group B rotavirus infections (36 vs 15%, P=0.02) and the virus was responsible for more severe dehydration compared with group A-infected patients (12 vs 3%, P=0.04). Sequence analyses of VP4, VP7 and NSP2 indicated that an Indian-Bangladeshi lineage of the virus, which is different from both the prototype (Chinese) lineage and from the animal group B rotaviruses, has been circulating in Bangladesh. Continuous monitoring of group B rotaviruses both in hospitals and in the community will be helpful to determine the true burden of group B rotaviruses.
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Where are ionic liquid strategies most suited in the pursuit of chemicals and energy from lignocellulosic biomass?
Chem. Commun. (Camb.)
PUBLISHED: 12-20-2010
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Certain ionic liquids have been shown to dissolve cellulose, other biopolymers, and even raw biomass under relatively mild conditions. This particular ability of some ionic liquids, accompanied by a series of concurrent advantages, enables the development of improved processing strategies for the manufacturing of a plethora of biopolymer-based advanced materials. The more recent discoveries of dissolution of lignocellulosic materials (e.g., wood) in ionic liquids, with at least partial separation of the major constituent biopolymers, suggest further paths towards the achievement of a truly sustainable chemical and energy economy based on the concept of a biorefinery which provides chemicals, materials, and energy. Nonetheless, questions remain about the use of ionic liquids and the advisability of introducing any new process which utilizes bulk synthetic chemicals which have to be made, disposed of, and prevented from entering the environment. In this article, we discuss our own journey from the discovery of the dissolution of cellulose in ionic liquids to the cusp of an enabling technology for a true biorefinery and consider some of the key questions which remain.
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Detection of a Rare HIV Type 1 Strain CRF16_A2D in Bangladesh.
AIDS Res. Hum. Retroviruses
PUBLISHED: 10-07-2010
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Circulating recombinant form (CRF) 16_A2D is a rare HIV strain among the most recently identified subsubtype A2. Samples taken from an HIV-seropositive married couple who attended a voluntary counseling and testing unit in Dhaka, Bangladesh showed two rare CRF16_A2D isolates. Further genetic analyses targeting three HIV genes (gag, pol, and env) showed that the two isolates from the couple were closely related making it likely that one of them acquired the virus and transferred it to the other. The husband admitted that he had contact with sex workers and both wife and husband had never traveled outside the country. This indicates that the husband might have acquired the virus from sex workers and that this rare strain is already circulating in the country. Detecting unusual isolates is important to determine the true diversity of HIV strains in the country. Monitoring of such strains will help in identifying transmission patterns and possible interventions to prevent the spread of HIV infection.
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Simultaneous discrimination of handedness and diameter of single-walled carbon nanotubes (SWNTs) with chiral diporphyrin nanotweezers leading to enrichment of a single enantiomer of (6,5)-SWNTs.
J. Am. Chem. Soc.
PUBLISHED: 08-05-2010
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Separation of single-walled carbon nanotubes (SWNTs) according to their handedness has been attracting growing interest. Our methodology to separate the enantiomers of SWNTs is based on molecular recognition with chiral diporphyrin nanotweezers. Herein, we report novel nanotweezers 1 consisting of two chiral porphyrins and phenanthrene in between. These nanotweezers 1 are rationally designed to discriminate diameter and handedness simultaneously by taking into account the relationship between the (n, m) selectivity and the structures of previously reported chiral nanotweezers. Owing to the relatively narrow cleft made by two porphyrins, the nanotweezers 1 showed high selectivity toward (6,5)-SWNTs possessing the smallest diameter among the major components of CoMoCAT-SWNTs. In addition, the chiral diporphyrin 1 discriminated the left- and right-handed structures of (6,5)-SWNTs, providing high enantiomeric excess (67% ee on the basis of the (6,5)-SWNTs with high optical purity recently reported by Weisman). In conclusion, only the single stereoisomer of (6,5)-SWNTs was highly enriched through the extraction of CoMoCAT-SWNTs with phenanthrene-bridged chiral diporphyrin nanotweezers 1.
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Rotavirus incidence and genotype distribution before and after national rotavirus vaccine introduction in Belgium.
Vaccine
PUBLISHED: 06-23-2010
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Rotarix™ was introduced into the Belgian market in 2006 and RotaTeq™ in 2007, quickly reaching more than 85% vaccine coverage of all newborns in Belgium. The incidence of rotavirus gastroenteritis has been monitored in the Gasthuisberg University Hospital (GUH), Belgium since 1986, and since 1999 the genotypes of circulating rotavirus strains have been determined. The average percentage of rotavirus positive cases out of all hospitalized gastro-enteritis cases tested (>95% of these cases are younger than 5 years old) at the GUH between 1986 and 2006 was 19.0%. This percentage dropped to 12.4%, 9.6% and 6.4% in the three seasons post vaccine introduction (2006-2009), which is a decline of 34.7%, 49.4% and 66.3% respectively. In addition the rotavirus season was found to be shortened and delayed. The prevalence of the G2 genotype sharply increased in the 2006-2007 rotavirus season compared to the previous seasons and remained high (30-40%) in the 2007-2008 and 2008-2009 seasons. Rotavirus vaccines have strongly reduced the number of children hospitalized due to a rotavirus infection at the GUH; it is however unclear if the predominance of G2 genotypes is related to the vaccine introduction, or if this is attributable to normal genotype fluctuations. Continued surveillance will be pivotal to answer this question in the future.
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Phylodynamic analyses of rotavirus genotypes G9 and G12 underscore their potential for swift global spread.
Mol. Biol. Evol.
PUBLISHED: 06-03-2010
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Rotaviruses (RVs) are responsible for more than 600,000 child deaths each year. The worldwide introduction of two life oral vaccines RotaTeq and Rotarix is believed to reduce this number significantly. Before the licensing of both vaccines, two new genotypes, G9 and G12, emerged in the human population and were able to spread across the entire globe in a very short time span. To quantify the VP7 mutation rates of these G9 and G12 genotypes and to estimate their most recent common ancestors, we used a Bayesian Markov chain Monte Carlo framework. Based on 356 sequences for G9 and 140 sequences for G12, we estimated mutation rates (nt substitutions/site/year) of 1.87 × 10(-3) (1.45-2.27 × 10(-3)) for G9 and 1.66 × 10(-3) (1.13-2.32 × 10(-3)) for G12. For both the G9 and G12 strains, one particular (sub) lineage was able to disseminate and cause disease across the world. The most recent common ancestors of these particular lineages were dated back to 1989 (1986-1992) and 1995 (1992-1998) for the G9 and G12 genotypes, respectively. These estimates suggest that a single novel RV (e.g., a vaccine escape mutant) can spread worldwide in little more than a decade. These results re-emphasize the need for thorough and continued RV surveillance in order to detect such potential spreading events at an early stage.
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Increased expression of HMGA1 correlates with tumour invasiveness and proliferation in human pituitary adenomas.
Histopathology
PUBLISHED: 05-13-2010
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High-mobility group A1 (HMGA1) is highly expressed in various benign and malignant tumours. The development of pituitary adenoma in Hmga1 transgenic mice has been reported. However, no studies have investigated HMGA1 expression and its clinical significance in human pituitary adenomas.
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Reassortment of human rotavirus gene segments into G11 rotavirus strains.
Emerging Infect. Dis.
PUBLISHED: 03-31-2010
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G11 rotaviruses are believed to be of porcine origin. However, a limited number of G11 rotaviruses have been recently isolated from humans in combination with P[25], P[8], P[6], and P[4]. To investigate the evolutionary relationships of these strains, we analyzed the complete genomes of 2 human G11P[25] strains, 2 human G11P[8] strains, and 3 porcine reference strains. Most of the 11 gene segments of these 7 strains belonged to genotype 1 (Wa-like). However, phylogenetic clustering patterns suggested that an unknown G11P[25] strain with a new I12 VP6 genotype was transmitted to the human population, in which it acquired human genotype 1 gene segments through reassortment, resulting in a human G11P[8] rotavirus strain with an entire human Wa-genogroup backbone. This Wa-like backbone is believed to have caused the worldwide spread of human G9 and G12 rotaviruses. G11 human rotavirus strains should be monitored because they may also become major human pathogens.
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Influenza is a major contributor to childhood pneumonia in a tropical developing country.
Pediatr. Infect. Dis. J.
PUBLISHED: 03-02-2010
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Pneumonia is the leading cause of child mortality worldwide. The role of influenza in childhood pneumonia in tropical developing countries is poorly understood. We undertook population-based surveillance among low-income urban preschool children to determine its role in childhood pneumonia.
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Molecular evolutionary analysis and mutational pattern of full-length genomes of hepatitis B virus isolated from Belgian patients with different clinical manifestations.
J. Med. Virol.
PUBLISHED: 01-21-2010
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Molecular evolutionary patterns of 62 HBV full-length genomes obtained from Belgian patients were characterized. Phylogenetic analysis revealed diverse HBV subgenotypes including A2 and A6 (46.8%), D1-D4 (38.8%), E (9.7%), C1 (1.6%), and B2 (1.6%). The study population consisted of patients with different ethnic origin (Caucasian, Turkish, Asian, Arab, and African). One HBV D/C recombinant isolate was identified, which encoded subtype adw2. An HBV subgenotype D4 with an aberrant subtype ayw4 was detected. Although none of the genotypes was associated with a specific disease outcome, several nucleotide substitutions, deletions and insertions were observed within the HBV preS1/S and X genes, particularly among patients with active chronic hepatitis B infection and patients with cirrhosis. Within the immunological domain of the HBsAg gene, the most frequent substitutions were sT125M and sT118A. High rates of precore and basal core promoter mutations were detected in patients infected with genotype D of HBV. Almost half of the patients who received lamivudine therapy for at least 1 year had HBV variants associated with lamivudine drug resistance. In conclusion, the most common HBV genotypes in West Europe (A and D) also prevail in Belgium. The highest degree of genetic diversity was detected in HBV genotype D. In addition, this study reveals the circulation of exotic HBV genotypes B, C, and E in Belgium. J. Med. Virol. 82:379-389, 2010. (c) 2010 Wiley-Liss, Inc.
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Complete genomic analysis of a Bangladeshi G1P[8] rotavirus strain detected in 2003 reveals a close evolutionary relationship with contemporary human Wa-like strains.
Infect. Genet. Evol.
PUBLISHED: 01-19-2010
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More than 120 variants of rotavirus strains with different VP7 (G type) and VP4 (P type) combinations are reported thus far. Among them Wa-like G1P[8] rotaviruses are the most common human strains worldwide. However, characterization of their entire genome complement is limited to a few old prototype strains, and no complete genome data for any G1P[8] strain isolated in the last decade are available. Both the currently licensed rotavirus vaccines Rotarix and RotaTeq possess the G1 and P[8] specificities. Therefore, comprehensive genetic information of the currently circulating G1P[8] strain is important to assess the impact of rotavirus vaccines on the circulating rotavirus strains. Here we report the complete genome sequence of a G1P[8] rotavirus strain Dhaka16-03 isolated in 2003 from a Bangladeshi child hospitalized with severe diarrhea. Based on a full-genome classification system, Dhaka16-03 was shown to posses the typical Wa-like genotype constellation: G1-P[8]-I1-R1-C1-M1-A1-N1-T1-E1-E1-H1. The strain was phylogenetically more closely related to contemporary human rotavirus strains (isolated in the 2000s) with a range of G and P-genotypes than to those of the prototype G1P[8] strains. Since the vaccine strains are developed based on strains isolated several decades ago, it is important to know how much the vaccine strains differ from the currently circulating G1P[8] and other Wa-like strains. Our complete genome characterization of a recent G1P[8] strain will be helpful to assess the ongoing rotavirus vaccine trials and their implementation programs in the forthcoming years.
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DNA methyltransferases 1, 3a, and 3b overexpression and clinical significance in gastroenteropancreatic neuroendocrine tumors.
Hum. Pathol.
PUBLISHED: 01-05-2010
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The alteration of DNA methylation is one of the most common epigenetic changes in human cancers. Three genes, namely, DNA methyltransferase 1, 3a, and 3b, which code for DNA methyltransferases that affect promoter methylation status, are thought to play an important role in the development of cancers and may be good anticancer therapy targets. The methylation of tumor suppressor genes has been reported in gastroenteropancreatic neuroendocrine tumors; however, there have been no studies about DNA methyltransferase protein expression and its clinical significance in gastroenteropancreatic neuroendocrine tumors. In this study, the expression of DNA methyltransferase 1, 3a, and 3b was studied in 63 gastroenteropancreatic neuroendocrine tumors by immunohistochemistry. The expression of DNA methyltransferase 1, 3a, and 3b was frequently detected in gastroenteropancreatic neuroendocrine tumors (87%, 81%, and 75%, respectively). The DNA methyltransferase 3a expression level was significantly higher in poorly differentiated neuroendocrine carcinomas than in well-differentiated neuroendocrine tumors or well-differentiated neuroendocrine carcinomas (P < .01 and P < .05, respectively). The expression of DNA methyltransferase 1, 3a, and 3b showed significantly higher levels in stage IV tumors than in stage I or II tumors. In addition, the expression levels of DNA methyltransferase 1, 3a, and 3b were positively correlated with the MIB-1 labeling index in gastroenteropancreatic neuroendocrine tumors (R = 0.293, P = .019; R = 0.457, P = .001; and R = 0.249, P = .049; respectively). In addition, the expression levels and positive immunostaining frequencies of DNA methyltransferase 3a and 3b were significantly lower in midgut neuroendocrine tumors than in foregut or hindgut neuroendocrine tumors. Our findings suggest that the overexpression of DNA methyltransferase 1, 3a, and 3b is related to tumorigenesis and the progression of gastroenteropancreatic neuroendocrine tumors.
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Rotavirus disease and vaccination: impact on genotype diversity.
Future Microbiol
PUBLISHED: 12-10-2009
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Temporal and spatial fluctuations in the genotype distribution of human rotaviruses are continuously observed in surveillance studies. New genotypes, such as G9 and G12, have emerged and spread worldwide in a very short time span. In addition, reassortment events have the potential to contribute substantially to genetic diversity among human and animal rotaviruses. With the recent introduction of the two rotavirus vaccines, RotaTeq and Rotarix, in many countries, it appears that the total number of hospitalizations due to rotavirus infections is being reduced, at least in developed countries that implemented a universal immunization program. However, continued surveillance is warranted, especially regarding the long-term effects of the vaccines. No data analyses are available to clarify whether rotavirus vaccine introduction would allow other rotavirus P and G genotypes, which are not covered by the current vaccines, to emerge into the human population and fill the apparent gap. This kind of data analysis is essential, but its interpretation is hampered by natural and cyclical genotype fluctuations.
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Surveillance of rotavirus in a rural diarrhoea treatment centre in Bangladesh, 2000-2006.
Vaccine
PUBLISHED: 11-26-2009
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Rotavirus was detected in 33% of 4519 children less than 5 years of age admitted with diarrhoea to treatment centres at Matlab in rural Bangladesh from 2000 to 2006. Highest rotavirus detection rates were in children aged 6-11 months with 56% being less than 1 year old. The peak seasonal detection was in July-September and December-February. The population-based incidence rates of rotavirus ranged from 10.8 to 19.6/1000 children less than 5 years of age. G1 serotype predominated between June 2002-May 2005 and June 2005-May 2006 the predominant type was G2 (41%) followed by G1 (22%) and G9 (22%). Rotavirus is an important cause of childhood diarrhoea in rural Bangladesh and this burden may be reduced with a rotavirus vaccination programme.
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Biphasic liquid mixtures of ionic liquids and polyethylene glycols.
Phys Chem Chem Phys
PUBLISHED: 10-13-2009
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We have found that 1-alkyl-3-methylimidazolium chloride ionic liquids (ILs) can form immiscible liquid mixtures with some polyethylene glycols (PEGs). Binary mixtures of 1-ethyl-3-methylimidazolium chloride with PEG of molecular weight 1500, 2000, or 3400 g mol(-1), or of 1-butyl-3-methylimidazolium chloride with PEG of molecular weight 2000 or 3400 g mol(-1), have been found to give rise to entirely liquid, stable biphasic systems over a significant temperature range (from 333.15 K to 413.15 K), while mixtures of 1-ethyl-3-methylimidazolium chloride with PEG-1000 and 1-butyl-3-methylimidazolium chloride with PEG-1000 and PEG-1500 are miscible. The mutual immiscibility of the IL and the PEG increases as the temperature increases. The evolution of the composition of the phases in equilibrium with the molecular weight of the PEG, or with the variation of the length of the alkyl substituent chain of the imidazolium cation of the IL, has been explored. The trends observed are explained through the complexity of interactions present within the binary system. A thermodynamic analysis of the liquid-liquid equilibrium data indicates negative values for the change of enthalpy and entropy of mixing. The potential application of these biphasic, entirely liquid systems, with low volatility and good solvation properties, for the dissolution and separation of cellulose and lignin at elevated temperature has been preliminarily explored, although only modest results have been achieved to date.
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Clinicopathological characterization of TSH-producing adenomas: special reference to TSH-immunoreactive but clinically non-functioning adenomas.
Endocr. Pathol.
PUBLISHED: 09-24-2009
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Thyrotropin (thyroid-stimulating hormone (TSH))-producing pituitary adenomas have been known to be quite variable in clinical features covering from typical functioning TSH-producing adenomas (FTSHomas) associated with hyperthyroidism to clinically silent TSH cell adenomas (STAs) that are apparently unassociated with hyperthyroidism. It is important to distinguish STAs from other types of clinically non-functioning adenomas for adequate postoperative managements. However, because of rareness of TSH-producing adenomas, their histopathological features linking to the clinical manifestations have not been well characterized. Herein, we investigated clinical and histopathological findings to characterize 29 TSH-producing adenomas including 20 FTSHomas and nine STAs. Clinical symptoms of the patients with STAs included headache, visual defect, vertigo, and nausea. All STAs and 19 FTSHomas were macroadenoma. The average tumor size of STAs was significantly larger than that of FTSHomas (P < 0.05). The invasiveness was detected in 33% STAs and in 20% FTSHomas. Both STAs and FTSHomas showed a variety of morphological features and immunohistochemical profiles. Chromophobic polygonal or short-spindled tumor cells usually proliferated in a diffuse pattern, while they exhibited globoid or whorl-like appearance with intertwined cytoplasmic processes in both subgroups. Stromal fibrosis and calcification were often noted. Their nuclei were somehow pleomorphic. Ultrastructural features of all four STAs examined were similar to those of normal thyrotrophs. Thus, STAs and FTSHomas were indistinguishable by histology alone. Immunohistochemically, the number of TSH-positive cells in individual FTSHomas was highly various. Six tumors showed only a few TSH-positive cells (1-5%), and three were negative for TSH by conventional method without antigen retrieval. After proteinase K treatment, these tumors turned out TSH positive. As defined, STAs were TSH positive in more than 20% of tumor cells and three of them in more than 50%. Growth hormone- and/or prolactin-positive cells were detected in 55% STAs and 63% FTSHomas. Both pituitary-specific transcription factor 1 and GATA-binding protein 2 were expressed in all STAs and 20 FTSHomas. Membranous somatostatin receptor (SSTR)-2A immunoreactivity was found in 89% STAs and 94% FTSHomas, whereas SSTR5 was positive in 78% of both STAs and FTSHomas. MIB-1 labeling index was related to tumor invasiveness and tumor size (P < 0.05, P = 0.09, respectively). Thus, although both STAs and FTSHomas showed unique histopathological features distinct from other type adenomas, these two subgroups were indistinguishable by histopathology. Immunohistochemistry for TSH by use of antigen retrieval, transcription factors, and SSTRs may be useful to confirm STAs and to determine the postoperative therapy among various kinds of clinically non-functioning adenomas.
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Avian influenza virus A (H5N1), detected through routine surveillance, in child, Bangladesh.
Emerging Infect. Dis.
PUBLISHED: 09-16-2009
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We identified avian influenza virus A (H5N1) infection in a child in Bangladesh in 2008 by routine influenza surveillance. The virus was of the same clade and phylogenetic subgroup as that circulating among poultry during the period. This case illustrates the value of routine surveillance for detection of novel influenza virus.
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Influenza in outpatient ILI case-patients in national hospital-based surveillance, Bangladesh, 2007-2008.
PLoS ONE
PUBLISHED: 08-03-2009
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Recent population-based estimates in a Dhaka low-income community suggest that influenza was prevalent among children. To explore the epidemiology and seasonality of influenza throughout the country and among all age groups, we established nationally representative hospital-based surveillance necessary to guide influenza prevention and control efforts.
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Are human P[14] rotavirus strains the result of interspecies transmissions from sheep or other ungulates that belong to the mammalian order Artiodactyla?
J. Virol.
PUBLISHED: 01-19-2009
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A limited number of human G6P[14] rotavirus strains that cause gastroenteritis in humans have been isolated in Europe and Australia. The complete genome sequences were determined for five of these human strains--B10925-97 (isolated in Belgium in 1997), 111/05-27 (Italy, 2005), PA169 (Italy, 1987), MG6 (Australia, 1993), and Hun5 (Hungary, 1997)--and their genetic relatedness to animal rotavirus strains was evaluated by sequencing the complete genome of the sheep rotavirus OVR762 (G8P[14]; Spain, 2002), the guanaco (Lama guanicoe) rotavirus strains Arg/Chubut/99 and Arg/Río Negro/98 (G8P[14] and G8P[1], respectively; Argentina, 1999 and 1998), the sable antelope strain RC-18/08 (G6P[14]; South Africa, 2008), and the bovine rotavirus strain Arg/B383/98 (G15P[11]; Argentina, 1998). These analyses revealed an overall consensus genomic constellation (G6/G8)-P[14]-I2-(R2/R5)-C2-M2-(A3/A11)-N2-T6-(E2/E12)-H3, together with a few gene reassortments, and the phylogenetic analyses confirmed that the P[14] human strains evaluated in this study were closely related to rotavirus strains isolated from sheep, cattle, goats, guanacos, and antelopes and to rabbits (albeit to a lesser extent), suggesting that one (or more) of these animal species might be the source of the human G6P[14] strains. The main feature of the genotype and phylogenetic analyses was the close overall genomic relatedness between the five human G6P[14] rotavirus strains and the ovine and antelope rotavirus strains. Taken together, these data strongly suggest a common origin for the human P[14] strains and those of the even-toed ungulates belonging to the mammalian order Artiodactyla, with sheep probably playing a key role in the interspecies transmission responsible for the introduction of P[14] rotavirus strains into the human population.
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Phylogenetic analysis of hepatitis B virus full-length genomes reveals evidence for a large nosocomial outbreak in Belgium.
J. Clin. Virol.
PUBLISHED: 01-17-2009
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Hepatitis B virus (HBV) is primarily transmitted from mother to child, by sexual contact, intravenous drug abuse, or unsafe health care-related injection practices. Despite increased safety efforts, nosocomial acquired hepatitis B infection remains problematic.
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Overexpression of HMGA2 relates to reduction of the let-7 and its relationship to clinicopathological features in pituitary adenomas.
Mod. Pathol.
PUBLISHED: 01-09-2009
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High-mobility group A2 is highly expressed during embryogenesis and in various benign and malignant tumors. Recent studies report that high-mobility group A2 is negatively regulated by the let-7 microRNAs (miRNAs) family in vitro. The development of pituitary adenomas in high-mobility group A2 transgenic mice showed that high-mobility group A2 may be involved in pituitary tumorigenesis. However, no studies have investigated the clinical significance of high-mobility group A2 and its relationship to the let-7 miRNA family in human pituitary adenomas. Using immunohistochemistry, we analyzed high-mobility group A2 expression with respect to various clinicopathologic factors in 98 pituitary adenomas. Overexpression of high-mobility group A2 was observed in 39% (38/98) of pituitary adenomas compared with normal adenohypophysial tissue and was frequently found in adenomas including prolactin (PRL), adrenocorticotrophic hormone, or follicle-stimulating hormone/luteinizing hormone and in null cell adenomas, but relatively rare in growth hormone (GH) and mixed GH/PRL adenomas. High-mobility group A2 expression was significantly associated with tumor invasion (P<0.05) and was significantly higher in grade IV than in grades I, II, and III adenomas (P<0.05). High levels of high-mobility group A2 expression were more frequently observed in macroadenomas than in microadenomas (P<0.05). High levels of high-mobility group A2 expression also significantly correlated with the proliferation marker Ki-67 (P<0.0001). Real-time quantitative RT-PCR analysis was carried out to evaluate the expression of let-7 in 55 pituitary adenomas. Subsequently, decreased expression of let-7 was confirmed in 23 of 55 (42%) adenomas and was correlated with high-grade tumors (P<0.05). An inverse correlation between let-7 and high-mobility group A2 expression was evident (R=-0.33, P<0.05). These findings support a causal link between let-7 and high-mobility group A2 whereby loss of let-7 expression induces high-mobility group A2 upregulation that represents an important mechanism in pituitary tumorigenesis and progression.
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RotaC: a web-based tool for the complete genome classification of group A rotaviruses.
BMC Microbiol.
PUBLISHED: 01-06-2009
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Group A rotaviruses are the most common cause of severe diarrhea in infants and children worldwide and continue to have a major global impact on childhood morbidity and mortality. In recent years, considerable research efforts have been devoted to the development of two new live, orally administered vaccines. Although both vaccines have proven to confer a good protection against severe rotavirus gastroenteritis, these vaccines will have to be screened and may have to be updated regularly to reflect temporal and spatial genotype fluctuations. In this matter, the genetic characterization of circulating and new emerging rotavirus strains will need to be compulsory and accurate. An extended classification system for rotaviruses in which all the 11 genomic RNA segments are used, has been proposed recently. The use of this classification system will help to elucidate the role of gene reassortments in the generation of genetic diversity, host range restriction, co-segregation of certain gene segments, and in adaptation to a new host species.
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Bronchiolitis outbreak caused by respiratory syncytial virus in southwest Bangladesh, 2010.
Int. J. Infect. Dis.
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During July 2010, newspapers reported a respiratory disease outbreak in southwestern Bangladesh resulting in the admission of children to a secondary care hospital. We investigated this outbreak to determine the etiology and explore possible risk factors.
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Calicivirus from novel Recovirus genogroup in human diarrhea, Bangladesh.
Emerging Infect. Dis.
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To identify unknown human viruses in the enteric tract, we examined 105 stool specimens from patients with diarrhea in Bangladesh. A novel calicivirus was identified in a sample from 1 patient and subsequently found in samples from 5 other patients. Phylogenetic analyses classified this virus within the proposed genus Recovirus.
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Nutrition of children and women in Bangladesh: trends and directions for the future.
J Health Popul Nutr
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Although child and maternal malnutrition has been reduced in Bangladesh, the prevalence of underweight (weight-for-age z-score <-2) among children aged less than five years is still high (41%). Nearly one-third of women are undernourished with body mass index of <18.5 kg/m2. The prevalence of anaemia among young infants, adolescent girls, and pregnant women is still at unacceptable levels. Despite the successes in specific programmes, such as the Expanded Programme on Immunization and vitamin A supplementation, programmes for nutrition interventions are yet to be implemented at scale for reaching the entire population. Given the low annual rate of reduction in child undernutrition of 1.27 percentage points per year, it is unlikely that Bangladesh would be able to achieve the United Nations Millennium Development Goal to address undernutrition. This warrants that the policy-makers and programme managers think urgently about the ways to accelerate the progress. The Government, development partners, non-government organizations, and the academia have to work in concert to improve the coverage of basic and effective nutrition interventions, including exclusive breastfeeding, appropriate complementary feeding, supplementation of micronutrients to children, adolescent girls, pregnant and lactating women, management of severe acute malnutrition and deworming, and hygiene interventions, coupled with those that address more structural causes and indirectly improve nutrition. The entire health system needs to be revitalized to overcome the constraints that exist at the levels of policy, governance, and service-delivery, and also for the creation of demand for the services at the household level. In addition, management of nutrition in the aftermath of natural disasters and stabilization of prices of foods should also be prioritized.
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Phorbol ester or epidermal growth-factor-induced MUC5AC mucin gene expression and production from airway epithelial cells are inhibited by apigenin and wogonin.
Phytother Res
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In this study, we investigated whether apigenin and wogonin affect MUC5AC mucin production and gene expression induced by phorbol ester (phorbol 12-myristate 13-acetate, PMA) or epidermal growth factor (EGF) from human airway epithelial cells. Confluent NCI-H292 cells were pretreated with each agent for 30?min and then stimulated with PMA or EGF for 24?h, respectively. MUC5AC mucin gene expression and mucin protein production were measured by reverse transcription polymerase chain reaction (RT-PCR) and enzyme linked immunosorbent assay (ELISA). The results were as follows: (i) apigenin and wogonin were found to inhibit the production of MUC5AC mucin protein induced by PMA or EGF; (ii) both compounds also inhibited the expression of MUC5AC mucin gene induced by PMA or EGF. These results suggest that apigenin and wogonin can inhibit mucin gene expression and production of mucin protein, by directly acting on airway epithelial cells.
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Incidence of respiratory virus-associated pneumonia in urban poor young children of Dhaka, Bangladesh, 2009-2011.
PLoS ONE
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Pneumonia is the leading cause of childhood death in Bangladesh. We conducted a longitudinal study to estimate the incidence of virus-associated pneumonia in children aged <2 years in a low-income urban community in Dhaka, Bangladesh.
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Alterations of serum zinc, copper, manganese, iron, calcium, and magnesium concentrations and the complexity of interelement relations in patients with obsessive-compulsive disorder.
Biol Trace Elem Res
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The purpose of the present study was to evaluate the status of serum trace elements: zinc, copper, manganese, iron, calcium, and magnesium concentrations in obsessive-compulsive disorder patients. Forty-eight obsessive-compulsive disorder patients and 48 healthy volunteers were included in this study. Patients were recruited from Bangabandhu Sheikh Mujib Medical University by random sampling. Serum trace element concentrations were determined using flame atomic absorption spectroscopy (for zinc, copper, iron, calcium, and magnesium) as well as graphite furnace atomic absorption spectroscopy (for manganese). Data were analyzed using independent t test, Pearsons correlation analysis, regression analysis, and ANOVA. Statistical analysis of these data showed a definite pattern of variation among certain elements in patients with obsessive-compulsive disorder compared to controls. In patients serum, zinc, iron, and magnesium concentrations decreased significantly (p<0.05) compared to the controls. Serum manganese and calcium concentrations were significantly higher (p<0.05) in patients compared to the controls. These data showed a definite imbalance in the interelement relations in obsessive-compulsive disorder patients compared to controls and therefore suggest a disturbance in the element homeostasis.
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Early detection of pandemic (H1N1) 2009, Bangladesh.
Emerging Infect. Dis.
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To explore Bangladeshs ability to detect novel influenza, we examined a series of laboratory-confirmed pandemic (H1N1) 2009 cases. During June-July 2009, event-based surveillance identified 30 case-patients (57% travelers); starting July 29, sentinel sites identified 252 case-patients (1% travelers). Surveillance facilitated response weeks before the spread of pandemic (H1N1) 2009 infection to the general population.
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What is Visualize?

JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

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We use abstracts found on PubMed and match them to JoVE videos to create a list of 10 to 30 related methods videos.

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In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.