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This paper reports on some physicochemical and phytochemical characteristics (i. e. pH, electrical conductivity, colour, moisture content, total phenolic content, sugar profile) and inâ vitro antioxidant activity of honeys harvested from five legume species, red clover (Trifolium pratense), balansa clover (T.â michelianum), Persian clover (T.â resupinatum), purple clover (T.â purpureum) and sanfoin, also known as holy clover (Onobrychis viciifolia), that were grown in enclosed shade houses to ensure that the honeys' characteristics are reflective of a truly monofloral honey. Glucose and fructose, determined via High-Performance Thin-Layer Chromatography (HPTLC) analysis, were found as the main sugars in all investigated honeys with the ratio of fructose to glucose ranging from 1 : 1.2 to 1 : 1.6. The honeys' pH values ranged from 3.9 to 4.6 which met Codes Alimentarius (CA) requirements. The moisture content was found to be between 17.6 and 22.2 % which in some cases was slightly higher than CA requirements (≤20 %). The honeys' colour values, prior and after filtration, were between 825.5-1149.5â mAU and 532.4-824.8â mAU respectively, illustrating golden yellow to deep yellow hues. The total phenolic content (TPC) of the honeys was determined using a modified Folin-Ciocalteu assay. Their antioxidant activity was captured by the Ferric Reducing-Antioxidant Power (FRAP) assay as well as HPTLC analysis coupled with 2,2-diphenyl-1-picrylhydrazyl (DPPH) derivatisation. The highest total phenolic content was found in red clover honey (45.4â mg GAE/100â g) whereas purple clover honey showed the highest level of activity in the FRAP assay (7.3â mmol Fe2+/kg). HPTLC-DPPH analysis of the honeys' organic extracts demonstrated the presence of various bioactive compounds that contribute to their overall antioxidant activity. This study developed a methodology for producing monofloral clover honeys in a space limited, enclosed production system, which allowed to collate important baseline data for these honeys that can serve as the foundation for their potential future development into commercial honeys, including honeys that can be used for medicinal purposes.
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Antioxidantes , Miel , Fitoquímicos , Antioxidantes/química , Antioxidantes/farmacología , Antioxidantes/análisis , Miel/análisis , Fitoquímicos/química , Fitoquímicos/farmacología , Fitoquímicos/análisis , Fitoquímicos/aislamiento & purificación , Fenoles/análisis , Fenoles/química , Concentración de Iones de Hidrógeno , Trifolium/química , Picratos/antagonistas & inhibidores , Compuestos de Bifenilo/antagonistas & inhibidores , Cromatografía en Capa DelgadaRESUMEN
Improved water, sanitation and hygiene (WASH) facilities in water-scarce areas is one of the most important barriers to improving the standards of people's life, which is even worse in a locality with forcibly displaced people (e.g., nearly 1 million Rohingya refugees in Bangladesh). In attempting to understand the extent of vulnerability and risks of WASH facilities, their impacts, and adaptive practices in the communities, an exploratory study has been carried out in five selected camps (13, 15, 16, 24 and 27) in Cox's Bazar, Bangladesh. Examination of water facilities shows that households in camps 13, 15 and 16 suffered from an adequate supply of water during summer as there is no direct access to surface water from adjacent water reservoirs, while camps 24 and 27 have such facilities. The frequency of water shortage for drinking purposes in camps 13, 15 and 16 was not so severe as in camps 24 and 27. Drinking water collectors had to spend 3-5 h in queues. All latrines were communal/shared latrines, which made users feel uncomfortable and vulnerable. This study implies that WASH facilities need to be reinforced, and community sensitization on WASH behavior needs to be strengthened to reduce WASH-related health hazards.
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Saneamiento , Agua , Humanos , Bangladesh , Mianmar , HigieneRESUMEN
Methylglyoxal (MGO) is considered to be one of the vital components responsible for the anti-bacterial activity of Leptospermum spp. (Manuka) honey. While many studies have demonstrated a dose-dependent antibacterial activity for MGO in vitro, from a therapeutic viewpoint, it is also important to confirm its release from Manuka honey and also from Manuka honey-based formulations. This study is the first to report on the release profile of MGO from five commercial products containing Manuka honey using a Franz diffusion cell and High-Performance Liquid Chromatography (HPLC) analysis. The release of MGO expressed as percentage release of MGO content at baseline was monitored over a 12 h period and found to be 99.49 and 98.05% from an artificial honey matrix and NZ Manuka honey, respectively. For the investigated formulations, a time-dependent % MGO release between 85% and 97.18% was noted over the 12 h study period.
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Miel , Miel/análisis , Piruvaldehído/química , Óxido de Magnesio , Cromatografía Líquida de Alta Presión , Leptospermum/química , Antibacterianos/farmacología , Antibacterianos/análisisRESUMEN
Grassland ecosystems are affected by the increasing frequency and intensity of extreme climate events (e.g., droughts). Understanding how grassland ecosystems maintain their functioning, resistance, and resilience under climatic perturbations is a topic of current concern. Resistance is the capacity of an ecosystem to withstand change against extreme climate, while resilience is the ability of an ecosystem to return to its original state after a perturbation. Using the growing season Normalized Difference Vegetation Index (NDVIgs, an index of vegetation growth) and the Standardized Precipitation Evapotranspiration Index (a drought index), we evaluated the response, resistance, and resilience of vegetation to climatic conditions for alpine grassland, grass-dominated steppe, hay meadow, arid steppe, and semi-arid steppe in northern China for the period 1982-2012. The results show that NDVIgs varied significantly across these grasslands, with the highest (lowest) NDVIgs values in alpine grassland (semi-arid steppe). We found increasing trends of greenness in alpine grassland, grass-dominated steppe, and hay meadow, while there were no detectable changes of NDVIgs in arid and semi-arid steppes. NDVIgs decreased with increasing dryness from extreme wet to extreme dry. Alpine and steppe grasslands exhibited higher resistance to and lower resilience after extreme wet, while lower resistance to and higher resilience after extreme dry conditions. No significant differences in resistance and resilience of hay meadow under climatic conditions suggest the stability of this grassland under climatic perturbations. This study concludes that highly resistant grasslands under conditions of water surplus are low resilient, but low resistant ecosystems under conditions of water shortage are highly resilient.
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Ecosistema , Pradera , Monitoreo del Ambiente , China , Estaciones del Año , Poaceae , Cambio ClimáticoRESUMEN
Climate change impacts crop production worldwide, and coastal regions are particularly vulnerable to its adverse effects. Given the projected rise in temperature and shifting precipitation patterns, it is crucial to examine the current challenges faced by farmers in coastal Bangladesh. Using Focus Group Discussions (FGDs) and Key Informant Interviews (KIIs), we assessed the perceptions and experiences of farmers and stakeholders regarding the existing agricultural practices, the challenges they face in crop cultivation, and the adoption of climate-adaptive practices in 2 sub-districts in the southeastern coastal region of Bangladesh. Moreover, using the Standardized Precipitation Evapotranspiration Index (SPEI) and the Standardized Terrestrial Water Storage Index (STI), we assessed the frequency and intensity of different climatic conditions in these two sub-districts. Results show that 100% of the respondents reported an increase in dry climatic conditions, the occurrence of untimely precipitation, and a decline in irrigation water during the cropping season. All the respondents in the FGDs expressed a loss of crop production because of these climate-induced disturbances. Despite these challenges, farmers have been implementing several climate-adaptive practices. Among the 9 mentioned climate-adaptive practices, 50% of FGD respondents utilize organic fertilizers, 42% cultivate heat- and drought-resilient crop varieties, use improved irrigation and harvest rainwater, and 25% cultivate integrated crops. The results of quantitative analysis of 3- and 6-month SPEI and STI values show that this region experienced frequent and intense dry climatic conditions during the growing-season, which supports the farmers' and stakeholders' concern about the increasing occurrence of droughts during crop growing periods. The results suggest that despite adopting climate-resilient practices under increasing growing-season droughts, farmers require support from the government and NGOs in capacity-building training and input support (e.g., stress-resilient seeds). This study holds practical implications for government, NGOs, and policymakers for ensuring sustainable agricultural productivity in the coastal region of Bangladesh.
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Agricultura , Cambio Climático , Productos Agrícolas , Agricultores , Bangladesh , Humanos , Productos Agrícolas/crecimiento & desarrollo , Agricultura/métodos , Riego Agrícola/métodos , Masculino , Producción de Cultivos/métodos , Sequías , Femenino , Grupos FocalesRESUMEN
Trace element pollution from anthropogenic sources is increasingly widespread. This pollution in terrestrial environments threatens agricultural crop production, while in aquatic environments, it threatens fish cultivation. The contamination of these crucial food sources raises significant concerns regarding food safety, security, and its potential adverse effects on human health. Coastal areas are particularly vulnerable to heavy metal pollution due to their proximity to industrial and urban centres, as well as their susceptibility to contamination from marine sources. In attempting to identify the sources of heavy metals (As, Cu, Cr, Cd, Fe, Hg, Mn, Ni, Pb, and Zn) and measure their contributions, we collected soil samples from thirty sites along the three coastal districts (Patuakhali, Barguna, and Bhola) in Bangladesh. Using atomic absorption spectroscopy, heavy metal concentrations in soil samples were measured and three receptor models (PMF, PCA-MLR, and UNMIX) were applied to detect their sources. Pairwise correlation analysis of metal concentrations in 30 sites across 3 coastal districts showed all possible patterns, including both significant and insignificant positive and negative relationships between different metals, except for As and Hg which did not display any significant relationships with other metals. The concentrations of Cu, Fe, Mn, Ni, and Zn exceed the US-EPA sediment quality standard. The applied PCA-MLR, PMF, and UNMIX models identified several sources of heavy metal contamination, including (i) mixed anthropogenic and natural activities: contribution of 59%, 37%, and 43%, and (ii) vehicle emissions: contribution of 23%, 26% and 29%. The recognized metal sources should be prioritised to avoid the discharge of poisonous pollutants from anthropogenic factors and any possible future exposure. This study's findings have implications for ongoing monitoring and management of heavy metal contamination in coastal environments to mitigate potential health and ecological impacts and can inform policy development and management strategies.
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Monitoreo del Ambiente , Sedimentos Geológicos , Metales Pesados , Bangladesh , Metales Pesados/análisis , Sedimentos Geológicos/química , Contaminantes del Suelo/análisis , Suelo/químicaRESUMEN
Oral liquid prednisolone medications have poor acceptance among paediatric patients due to ineffective masking of the bitterness taste of prednisolone. This study aimed to develop a child-friendly prednisolone tablet using a patented chewable chocolate-based delivery system (CDS) previously applied successfully to mask the bitterness tastes of midazolam and tramadol. Prednisolone sodium phosphate (PSP) and prednisolone base (PB) CDS tablets were prepared, and the manufacturing process was optimised using a design of experiments (DoE) approach. Stability was assessed by quantifying residual drug content via a validated HPLC assay. A pilot randomised crossover taste study involving 25 young adult volunteers evaluated taste-masking effectiveness against Redipred™, a commercial oral PSP liquid medicine. The results showed that the PSP CDS tablet was chemically stable following storage for three months at ambient temperature, while the PB CDS tablet was unstable. The optimised PSP CDS tablet, manufactured at 50 °C with a stirring time of 26 h, was found to release over 80% of its drug load within 20 min in 0.1 M HCl and had a significantly better mean taste score compared to Redipred™ (7.08 ± 2.40 vs. 5.60 ± 2.33, p = 0.03). Fifty six percent of the participants preferred the PSP CDS tablet. In conclusion, compared to Redipred™, the CDS technology provided a more effective taste masking of PSP, potentially offering a child-friendly prednisolone formulation with improved compliance, dosing accuracy, and storage stability.
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Honey has widespread use as a nutritional supplement and flavouring agent. Its diverse bioactivities, including antioxidant, antimicrobial, antidiabetic, anti-inflammatory, and anticancer properties, have also made it an aspirant natural product for therapeutic applications. Honey is highly viscous and very sticky, and its acceptance as a medicinal product will require formulation into products that are not only effective but also convenient for consumers to use. This study presents the design, preparation, and physicochemical characterisation of three types of alginate-based topical formulations incorporating a honey. The honeys applied were from Western Australia, comprising a Jarrah honey, two types of Manuka honeys, and a Coastal Peppermint honey. A New Zealand Manuka honey served as comparator honey. The three formulations were a pre-gel solution consisting of 2-3% (w/v) sodium alginate solution with 70% (w/v) honey, as well as a wet sheet and a dry sheet. The latter two formulations were obtained by further processing the respective pre-gel solutions. Physical properties of the different honey-loaded pre-gel solutions (i.e., pH, colour profile, moisture content, spreadability, and viscosity), wet sheets (i.e., dimension, morphology, and tensile strength) and dry sheets (i.e., dimension, morphology, tensile strength, and swelling index) were determined. High-Performance Thin-Layer Chromatography was applied to analyse selected non-sugar honey constituents to assess the impacts of formulation on the honey chemical composition. This study demonstrates that, irrespective of the honey type utilised, the developed manufacturing techniques yielded topical formulations with high honey content while preserving the integrity of the honey constituents. A storage stability study was conducted on formulations containing the WA Jarrah or Manuka 2 honey. The samples, appropriately packaged and stored over 6 months at 5, 30, and 40 °C, were shown to retain all physical characteristics with no loss of integrity of the monitored honey constituents.
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The aim of this study was to assess the release profile of components in five different honeys (a New Zealand Manuka and two Western Australian honeys, a Jarrah honey and a Coastal Peppermint honey) and their corresponding honey-loaded gel formulations using a custom-designed Franz-type diffusion cell in combination with High-Performance Thin-Layer Chromatography (HPTLC). To validate the suitability of the customised setup, release data using this new approach were compared with data obtained using a commercial Franz cell apparatus, which is an established analytical tool to monitor the release of active ingredients from topical semisolid products. The release profiles of active compounds from pure honey and honey-loaded formulations were found to be comparable in both types of Franz cells. For example, when released either from pure honey or its corresponding pre-gel formulation, the percentage release of two Jarrah honey constituents, represented by distinct bands at RF 0.21 and 0.53 and as analysed by HPTLC, was not significantly different (p = 0.9986) at 12 h with over 99% of these honey constituents being released in both apparatus. Compared to the commercial Franz diffusion cell, the customised Franz cell offers several advantages, including easy and convenient sample application, the requirement of only small sample quantities, a large diffusion surface area, an ability to analyse 20 samples in a single experiment, and lower cost compared to purchasing a commercial Franz cell. Thus, the newly developed approach coupled with HPTLC is conducive to monitor the release profile of minor honey constituents from pure honeys and honey-loaded semisolid formulations and might also be applicable to other complex natural-product-based products.
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Drought is a widespread hazard that can tremendously affect the biodiversity, habitat of wild species, and ecosystem functioning and stability, especially in the dry region. Due to its geographic location, the north-western region of Bangladesh has a comparatively arid climate which is very much susceptible to drought occurrence and is marked as a red zone. Despite the growing evidence of the impact of drought on food security and ecosystem functioning, little effort has been paid to mitigate the drought in this region. The present study aimed to assess the drought condition of the north-western region of Bangladesh using earth observation techniques. For this purpose, Landsat data from 1990 to 2020 was used to determine various vegetation indices such as Normalized Difference Vegetation Index (NDVI), Water Index (NDWI), Moisture Index (NDMI) and Soil Adjusted Vegetation Index (SAVI), along with Land Surface Temperature (LST). Results show that the depletion of forests (2832 km2) and water bodies (6773 km2) resulted from the expansion of settlement (6563 km2) and agricultural land (1802 km2) for the period 1990-2020. Examination of the temporal changes of vegetation indices and LST showed that the values of all indices decreased while the LST increased. The negative correlation between NDVI value and LST indicates that the vegetation in our study was subject to drought-induced shocks. This study reveals the current situation of the vegetation health in the north-western region of Bangladesh in relation to the drought conditions. The findings of this study have practical implications for the policymakers in implementing necessary measures for agriculture, forests, water development, and economic zone planning.
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Understanding the role of biodiversity in maintaining ecosystem functioning and stability under increasing frequency and magnitude of climatic extremes has fascinated ecologists for decades. Although growing evidence suggests that biodiversity affects ecosystem productivity and buffers ecosystem against climatic extremes, it remains unclear whether the stability of an ecosystem is caused by its resistance against disturbances or resilience towards perturbations or both. In attempting to explore how species richness affects resistance and resilience of above-ground net primary productivity (ANPP) against climatic extremes, we analyzed the grassland ANPP of the long-running (1997-2020) Bayreuth Biodiversity experiment in Germany. We used the Standardized Precipitation Evapotranspiration Index to identify climatic conditions based on 5- and 7-class classifications of climatic conditions. Mixed-effects models and post-hoc test show that ANPP varied significantly among different intensities (e.g. moderate or extreme) and directions (e.g. dry or wet) of climatic conditions, with the highest ANPP in extreme wet and the lowest in extreme dry conditions. Resistance and resilience of ANPP to climatic extremes in different intensities were examined by linear-mixed effects models and we found that species richness increased ecosystem resistance against all dry and wet climatic extremes, but decreased ecosystem resilience towards all dry climatic extremes. Species richness had no effects on ecosystem resilience towards wet climatic extremes. When the five level of species richness treatment (i.e., 1, 2, 4, 8, and 16 species) were considered, the relationships between species richness and resistance and resilience of ANPP under extreme wet and dry conditions remained similar. Our study emphasizes that plant communities with greater species richness need to be maintained to stabilize ecosystem productivity and increase resistance against different climatic extremes.
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Ecosistema , Pradera , Biodiversidad , Clima , Cambio ClimáticoRESUMEN
Honey, a naturally sweet and viscous substance is mainly produced by honeybees (Apis mellifera) from flower nectar. Honey exerts a plethora of biological and pharmacological activities, namely, antioxidant, antimicrobial and anti-inflammatory activity, because of the presence of an extensive variety of bioactive compounds. The antibacterial activity is one of the most reported biological properties, with many studies demonstrating that honey is active against clinically important pathogens. As a result, beside honey's widespread utilization as a common food and flavouring agent, honey is an attractive natural antimicrobial agent. However, the use of neat honey for therapeutic purposes poses some problems, for instance, its stickiness may hamper its appeal to consumers and health care professionals, and the maintenance of an adequate therapeutic concentration over a sufficient timeframe may be challenging due to honey liquidity and leakage. It has motivated researchers to integrate honey into diverse formulations, for example, hydrogels, dressings, ointments, pastes and lozenges. The antibacterial activity of these formulations should be scientifically determined to underscore claims of effectiveness. Some researchers have made efforts to adapt the disc carrier and suspension test to assess the antimicrobial activity of topical products (e.g., silver-based wound dressings). However, there is currently no established and validated method for determining the in vitro antimicrobial potential of natural product-based formulations, including those containing honey as the active principle. Against the backdrop of a brief discussion of the parameters that contribute to its antibacterial activity, this review provides an outline of the methods currently used for investigating the antibacterial activity of neat honey and discusses their limitations for application to honey-based formulations.
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The aim of this study was to optimise the so-called agar overlay assay to investigate the antimicrobial activity of some currently available topical antimicrobial products against a range of Gram positive and Gram negative bacteria. During the optimisation process, various assay parameters including base agar volume, overlay agar volume, overlay agar concentration, placement of products into wells or onto coverslip and inoculum concentration were taken into consideration. The optimised assay was found to be a convenient, suitable and effective platform for the assessment of the antimicrobial activity of commercial semi-solid over-the-counter (OTC) products (i.e. non-prescription medicines for topical application used commonly without supervision by a healthcare professional) containing a range of active pharmaceutical ingredients and to be potentially also applicable to complex natural product-based formulations (e.g. honey-based formulation, melaleuca oil-based formulation). The most auspicious aspect of the optimised method was its capability of determining the antimicrobial activity of intact products without further manipulation, unlike other tests that require products to be dissolved or dilute, thus compromising their integrity.
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Antiinfecciosos Locales , Antiinfecciosos , Miel , Humanos , Antiinfecciosos Locales/farmacología , Pruebas de Sensibilidad Microbiana , Bacterias Gramnegativas , Agar , Antibacterianos/farmacología , Bacterias Grampositivas , Antiinfecciosos/farmacologíaRESUMEN
Elucidating the variation in grassland belowground biomass (BGB) and its response to changes in climatic variables are key issues in plant ecology research. In this study, BGB data for five ecoregions (cold steppe, temperate dry steppe, savanna, humid savanna, and humid temperate) were used to examine the effects of climatic variability and extremes on the BGB of C3- and C4-dominated grasslands. Results showed that BGB varied significantly across the ecoregions, with the highest levels in cold steppe and the lowest in savanna. The results indicated that growing-season temperature, maximum and minimum temperatures and their interactions had significantly positive effects on the single-harvest BGB of C3 plants in colder ecoregions (i.e., humid temperate and cold steppe) and of C4 plants in arid ecoregions (i.e., temperate dry steppe and savanna). The single-harvest BGB of C3 plants in arid ecoregions and C4 plants in humid savanna ecoregion declined with increasing temperature during the growing season. Growing-season precipitation exerted significant positive effects on the single-harvest BGB of C4 plants in arid ecoregions. Annual temperature variables negatively impacted the annual BGB of humid temperate ecoregion, because of the dominance of C3 plants. Increasing cumulative growing-season precipitation elevated and the mean annual temperature reduced the annual BGB of both categories of plants in arid ecoregions. Compared with normal climates, extreme dry events during the growing season enhanced single-harvest BGB in colder ecoregions. The single-harvest BGB of C4 plants in savanna tended to increase during extreme wet and decrease during moderate dry events compared to normal climates. This study suggests that the differential effects of climatic variability and extremes on BGB can be explained by differences in plant types, and ecoregions. These findings on the responses of the BGB to climatic variability and extremes constitute important scientific evidence emphasizing the need to maintain ecosystem stability across ecoregions.
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Ecosistema , Pradera , Biomasa , Poaceae , LluviaRESUMEN
Increasing frequency and intensity of climate extremes have profound impacts on grassland biodiversity functioning and stability. Using Moderate Resolution Imaging Spectroradiometer (MODIS) net primary productivity (NPP) data and standardized precipitation evapotranspiration index, we assessed the response of NPP to growing-season and annual climate extremes and time-lag of climatic conditions across four grassland types (meadow steppe, typical steppe, steppe desert, and desert steppe) in Inner Mongolia, China from the period 2000 to 2019. Results showed that annual NPP varied significantly across four grassland types, with the highest NPP in meadow steppe and the lowest in desert steppe. Annual NPP of all grassland types increased over the past 20 years, but NPP in meadow steppe and typical steppe decreased for the period 2012-2019. Irrespective of grassland type, the 1- and 2-month time-lag of climatic conditions showed significant effects on annual NPP. Growing-season climate was found the better predictor of annual NPP in all grassland types than the annual climate. Compared with growing-season normal climates, annual NPP was lowest in extreme dry events in all grasslands, while highest in extreme wet events in meadow steppe and typical steppe, and in moderate wet events in steppe desert and desert steppe. Typical steppe and steppe desert are highly vulnerable to the increasing intensity of climate extremes, as we found that the losses of NPP in these grasslands in extreme dry were almost double than that of moderate dry events. Surprisingly, for meadow steppe and desert steppe, the losses of NPP for both moderate and extreme dry events were almost the same, which highlights that a low-intensity drought may have profound impacts on the annual NPP of these grasslands. The study provides the key insight in scientific basis to improve our understanding of the effects of climate extremes on grassland NPP, which is critical to sustainable management of grassland and maintain ecosystem stability.
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BACKGROUND: Children bear a large burden of typhoid fever caused by Salmonella enterica serotype Typhi (S. Typhi) in endemic areas. However, immune responses and clinical findings in children are not well defined. Here, we describe clinical and immunological characteristics of young children with S. Typhi bacteremia, and antimicrobial susceptibility patterns of isolated strains. METHODS: As a marker of recent infection, we have previously characterized antibody-in-lymphocyte secretion (TPTest) during acute typhoid fever in adults. We similarly assessed membrane preparation (MP) IgA responses in young children at clinical presentation, and then 7-10 days and 21-28 days later. We also assessed plasma IgA, IgG and IgM responses and T cell proliferation responses to MP at these time points. We compared responses in young children (1-5 years) with those seen in older children (6-17 years), adults (18-59 years), and age-matched healthy controls. PRINCIPAL FINDINGS: We found that, compared to age-matched controls patients in all age cohorts had significantly more MP-IgA responses in lymphocyte secretion at clinical presentation, and the values fell in all groups by late convalescence. Similarly, plasma IgA responses in patients were elevated at presentation compared to controls, with acute and convalescent IgA and IgG responses being highest in adults. T cell proliferative responses increased in all age cohorts by late convalescence. Clinical characteristics were similar in all age cohorts, although younger children were more likely to present with loss of appetite, less likely to complain of headache compared to older cohorts, and adults were more likely to have ingested antibiotics. Multi-drug resistant strains were present in approximately 15% of each age cohort, and 97% strains had resistance to nalidixic acid. CONCLUSIONS: This study demonstrates that S. Typhi bacteremia is associated with comparable clinical courses, immunologic responses in various age cohorts, including in young children, and that TPTest can be used as marker of recent typhoid fever, even in young children.
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Bacteriemia/inmunología , Salmonella typhi/efectos de los fármacos , Fiebre Tifoidea/epidemiología , Fiebre Tifoidea/inmunología , Adolescente , Adulto , Antibacterianos/farmacología , Bangladesh/epidemiología , Proliferación Celular/fisiología , Niño , Preescolar , Femenino , Humanos , Masculino , Persona de Mediana Edad , Salmonella typhi/inmunología , Especificidad de la Especie , Linfocitos T/inmunología , Adulto JovenRESUMEN
The concentrations of 18 different elements (K, Ca, Fe, Cl, P, Zn, S, Mn, Ti, Cr, Rb, Co, Br, Sr, Ru, Si, Ni, and Cu) were analyzed in five selected vegetables through Proton Induced X-ray Emission (PIXE) technique. The objective of this study was to provide updated information on concentrations of elements in vegetables available in the local markets at Savar subdistrict in Bangladesh. These elements were found in varying concentrations in the studied vegetables. The results also indicated that P, Cl, K, Ca, Mn, Fe, and Zn were found in all vegetables. Overall, K and Ca exhibited the highest concentrations. Cu and Ni exhibited the lowest concentrations in vegetables. The necessity of these elements was also evaluated, based on the established limits of regulatory standards. The findings of this study suggest that the consumption of these vegetables is not completely free of health risks.
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Brassica/química , Elementos Químicos , Hyacinthus/química , Lactuca/química , Espectrometría por Rayos X/métodos , Spinacia oleracea/química , Verduras/química , BangladeshRESUMEN
BACKGROUND: Rapid and reliable diagnostic assays for enteric (typhoid and paratyphoid) fever are urgently needed. We report the characterization of novel approach utilizing lymphocyte secretions, for diagnosing patients with enteric fever by the TPTest procedure. METHODOLOGY: TPTest detects Salmonella-specific IgA responses in lymphocyte culture supernatant. We utilized TPTest in patients with suspected enteric fever, patients with other illnesses, and healthy controls. We also evaluated simplified modifications of TPTest for adaptation in laboratories with limited facilities and equipment. PRINCIPAL FINDINGS: TPTest was positive in 39 (27 typhoid and 12 paratyphoid A) patients confirmed by blood culture and was negative in 74 healthy individuals. Among 32 individuals with other illnesses, 29 were negative by TPTest. Of 204 individuals with suspected enteric fever who were negative by blood culture, 44 were positive by TPTest and the patients were clinically indistinguishable from patients with confirmed bacteremia, except they were more likely to be under 5 years of age. We evaluated simplifications in TPTest, including showing that lymphocytes could be recovered using lysis buffer or buffy coat method as opposed to centrifugation, that incubation of cells at 37°C did not require supplemental CO2, and that results were available for majority of samples within 24 hours. Positive results by TPTest are transient and revert to negative during convalescence, supporting use of the test in endemic areas. The results can also be read using immunodot blot approach as opposed to ELISA. Since no true gold standard currently exists, we used a number of definitions of true positives and negatives. TPTest had sensitivity of 100% compared to blood culture, and specificity that ranged from 78-97% (73-100, 95% CI), depending on definition of true negative. CONCLUSION: The TPTest is useful for identification of patients with enteric fever in an endemic area, and additional development of simplified TPTest is warranted.
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Anticuerpos Antibacterianos/análisis , Pruebas Diagnósticas de Rutina/métodos , Inmunoglobulina A/análisis , Leucocitos Mononucleares/inmunología , Fiebre Paratifoidea/diagnóstico , Fiebre Tifoidea/diagnóstico , Adolescente , Adulto , Bangladesh , Células Cultivadas , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Persona de Mediana Edad , Sensibilidad y Especificidad , Adulto JovenRESUMEN
This study was conducted to determine the breeding season, gonadal development, egg laying period, clutch size and other biological aspects of spotted flapshell turtle, Lissemys punctata, of Bangladesh between January 1997 and December 2001. The egg laying period of L. punctata, was found between August and March. The nesting sites were elevated fallow lands in secluded areas. The female turtle laid all the mature eggs at a time for each clutch at night. A gravid female turtle laid three clutches of eggs in each year and the mean clutch size was 13.0 ± 1.9 eggs and mean weight of each egg was 10.3 ± 1.3 g. The eggs are spherical in shape and whitish in color. The mean incubation period was 173 ± 34 days (range 119-225 days). The incubation period of first clutch was the longest than the second and third clutches. Hatching success was found 41%. Maximum hatching was observed in June. The present investigation was made to explore the possibility to raise turtle farming in captive condition. The findings would, hopefully, help to rear the species and to assess the commercial potentiality of turtle farming in captive condition, that is, in the eco-climatic condition of Bangladesh.