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1.
Epidemiol Infect ; 152: e14, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-38178722

RESUMO

Using two rounds of serosurveillance, we aimed to observe the COVID-19 vaccination status and the dynamics of antibody responses to different vaccines among urban slum and non-slum populations of Bangladesh. Adults (>18 years) and children (10-17 years) were enrolled in March and October 2022. Data including COVID-19 vaccine types and dosage uptake were collected. SARS-CoV-2 spike (S)-specific antibodies were measured in blood. The proportion of vaccinated children was significantly lower among slum than non-slum populations. Two doses of vaccines showed an increase in the level of anti-S-antibodies up to 2 months, followed by reduced levels at 2-6 months and a resurgence at 6-12 months. Children showed significantly higher anti-S-antibodies after two doses of the Pfizer-BioNTech vaccine than adults; however, after 6 months, the level of antibodies declined in younger children (10 - < 12 years). In a mixed vaccine approach, mRNA vaccines contributed to the highest antibody response whether given as the first two doses or as the third dose. Our findings emphasized the need for increasing the coverage of COVID-19 vaccination among slum children and booster dosing among all children. The use of mRNA vaccines in the mixed vaccination approach was found to be useful in boosting the antibody response to SARS-CoV-2.


Assuntos
COVID-19 , Áreas de Pobreza , Adulto , Criança , Humanos , Vacinas contra COVID-19 , População Urbana , Bangladesh/epidemiologia , Vacinas de mRNA , COVID-19/epidemiologia , COVID-19/prevenção & controle , SARS-CoV-2
2.
Chem Biodivers ; 21(2): e202301492, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38150556

RESUMO

Rotundic acid (RA) is a naturally occurring pentacyclic triterpene with a multitude of pharmacological activities. The primary emphasis of this study is on summarizing the anticancer properties with the underlying mechanisms of RA and its derivatives, as well as the pharmacokinetic features. Data was collected (up to date as of November 10, 2023) from various reliable and authentic literatures by searching in different academic search engines, including PubMed, Springer Link, Scopus, Wiley Online, Web of Science, ScienceDirect, and Google Scholar. The findings imply that RA and its synthetic derivatives possess promising anti-cancer properties against breast, colorectal, liver, and cervical cancers in various preclinical pharmacological test systems. The results also indicate that RA and its derivatives demonstrated anticancer effects via a number of cellular mechanisms, including apoptotic cell death, inhibition of oxidative stress, anti-inflammatory effect, cytotoxicity, cell cycle arrest, anti-proliferative effect, anti-angiogenic effect, and inhibition of cancer cell migration and invasion. It has been proposed that RA and its derived compounds have the capability to serve as a hopeful chemotherapeutic agent, so further extensive clinical research is necessary.


Assuntos
Neoplasias , Triterpenos , Humanos , Neoplasias/tratamento farmacológico , Triterpenos/farmacologia , Pontos de Checagem do Ciclo Celular
3.
Chem Biodivers ; 21(5): e202301615, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38506600

RESUMO

Fruits and vegetables serve not only as sources of nutrition but also as medicinal agents for the treatment of diverse diseases and maladies. These dietary components are significant resources of phytochemicals that demonstrate therapeutic properties against many illnesses. Fraxin is a naturally occurring coumarin glycoside mainly present in various species of Fraxinus genera, having a multitude of therapeutic uses against various diseases and disorders. This study focuses to investigate the pharmacological activities, botanical sources, and biopharmaceutical profile of the phytochemical fraxin based on different preclinical and non-clinical studies to show the scientific evidence and to evaluate the underlying molecular mechanisms of the therapeutic effects against various ailments. For this, data was searched and collected (as of February 15, 2024) in a variety of credible electronic databases, including PubMed/Medline, Scopus, Springer Link, ScienceDirect, Wiley Online, Web of Science, and Google Scholar. The findings demonstrated favorable outcomes in relation to a range of diseases or medical conditions, including inflammation, neurodegenerative disorders such as cerebral ischemia-reperfusion (I/R) and depression, viral infection, as well as diabetic nephropathy. The phytochemical also showed protective effects such as osteoprotective, renoprotective, pulmoprotective, hepatoprotective, and gastroprotective effects due to its antioxidant capacity. Fraxin has a great capability to diminish oxidative stress-related damage in different organs by stimulating the antioxidant enzymes, downregulating nuclear factor kappa B and NLRP3, and triggering the Nrf2/ARE signaling pathways. Fraxin exhibited poor oral bioavailability because of reduced absorption and a wide distribution into tissues of different organs. However, extensive research is required to decipher the biopharmaceutical profiles, and clinical studies are necessary to establish the efficacy of the natural compound as a reliable therapeutic agent.


Assuntos
Compostos Fitoquímicos , Humanos , Animais , Compostos Fitoquímicos/farmacologia , Compostos Fitoquímicos/química , Compostos Fitoquímicos/isolamento & purificação , Furocumarinas/farmacologia , Furocumarinas/química , Furocumarinas/isolamento & purificação , Antioxidantes/farmacologia , Antioxidantes/química
4.
Molecules ; 28(16)2023 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-37630393

RESUMO

Fruits and vegetables are used not only for nutritional purposes but also as therapeutics to treat various diseases and ailments. These food items are prominent sources of phytochemicals that exhibit chemopreventive and therapeutic effects against several diseases. Hirsutine (HSN) is a naturally occurring indole alkaloid found in various Uncaria species and has a multitude of therapeutic benefits. It is found in foodstuffs such as fish, seafood, meat, poultry, dairy, and some grain products among other things. In addition, it is present in fruits and vegetables including corn, cauliflower, mushrooms, potatoes, bamboo shoots, bananas, cantaloupe, and citrus fruits. The primary emphasis of this study is to summarize the pharmacological activities and the underlying mechanisms of HSN against different diseases, as well as the biopharmaceutical features. For this, data were collected (up to date as of 1 July 2023) from various reliable and authentic literature by searching different academic search engines, including PubMed, Springer Link, Scopus, Wiley Online, Web of Science, ScienceDirect, and Google Scholar. Findings indicated that HSN exerts several effects in various preclinical and pharmacological experimental systems. It exhibits anti-inflammatory, antiviral, anti-diabetic, and antioxidant activities with beneficial effects in neurological and cardiovascular diseases. Our findings also indicate that HSN exerts promising anticancer potentials via several molecular mechanisms, including apoptotic cell death, induction of oxidative stress, cytotoxic effect, anti-proliferative effect, genotoxic effect, and inhibition of cancer cell migration and invasion against various cancers such as lung, breast, and antitumor effects in human T-cell leukemia. Taken all together, findings from this study show that HSN can be a promising therapeutic agent to treat various diseases including cancer.


Assuntos
Agaricales , Alcaloides , Produtos Biológicos , Animais , Humanos , Produtos Biológicos/farmacologia , Produtos Biológicos/uso terapêutico , Verduras
5.
Molecules ; 28(24)2023 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-38138491

RESUMO

The pursuit of innovative combinations for the development of novel antimicrobial and antiviral medications has garnered worldwide interest among scientists in recent times. Monosaccharides and their glycosides, such as methyl α-d-mannopyranoside derivatives, play a significant role in the potential treatment of viral respiratory pathologies. This study was undertaken to investigate and assess the synthesis and spectral characterization of methyl α-d-mannopyranoside derivatives 2-6, incorporating various aliphatic and aromatic groups. The investigation encompassed comprehensive in vitro antimicrobial screening, examination of physicochemical properties, molecular docking analysis, molecular dynamics simulations, and pharmacokinetic predictions. A unimolar one-step cinnamoylation reaction was employed under controlled conditions to produce methyl 6-O-cinnamoyl-α-d-mannopyranoside 2, demonstrating selectivity at the C-6 position. This represented a pivotal step in the development of potential antimicrobial derivatives based on methyl α-d-mannopyranoside. Subsequently, four additional methyl 6-O-cinnamoyl-α-d-mannopyranoside derivatives were synthesized with reasonably high yields. The chemical structures of these novel analogs were confirmed through a thorough analysis of their physicochemical properties, elemental composition, and spectroscopic data. In vitro antimicrobial assays were conducted against six bacterial strains and two fungal strains, revealing promising antifungal properties of these methyl α-d-mannopyranoside derivatives in comparison to their antibacterial activity. Moreover, cytotoxicity testing revealed that the compounds are less toxic. Further supporting these findings, molecular docking studies were performed against the H5N1 influenza A virus, indicating significant binding affinities and nonbonding interactions with the target protein 6VMZ. Notably, compounds 4 (-7.2) and 6 (-7.0) exhibited the highest binding affinities. Additionally, a 100 ns molecular dynamics simulation was conducted to assess the stability of the complex formed between the receptor 6VMZ and methyl α-d-mannopyranoside derivatives under in silico physiological conditions. The results revealed a stable conformation and binding pattern within the stimulating environment. In silico pharmacokinetic and toxicity assessments of the synthesized molecules were performed using Osiris software (version 2.9.1). Compounds 4 and 6 demonstrated favorable computational and pharmacological activities, albeit with a low drug score, possibly attributed to their higher molecular weight and irritancy. In conclusion, this study showcases the synthesis and evaluation of methyl α-d-mannopyranoside derivatives as promising candidates for antimicrobial and antifungal agents. Molecular docking and dynamics simulations, along with pharmacological predictions, contribute to our understanding of their potential therapeutic utility, although further research may be warranted to address certain pharmacological aspects.


Assuntos
Anti-Infecciosos , Virus da Influenza A Subtipo H5N1 , Simulação de Acoplamento Molecular , Manose , Anti-Infecciosos/química , Antibacterianos/química , Antifúngicos/química , Estrutura Molecular , Relação Estrutura-Atividade
6.
Medicina (Kaunas) ; 59(7)2023 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-37512091

RESUMO

Background and Objectives: The morbidity and mortality associated with COVID-19 have burdened worldwide healthcare systems beyond their capacities, forcing them to promptly investigate the virus characteristics and its associated outcomes. This clinical analysis aimed to explore the key factors related to the fatal outcome of severe COVID-19 cases. Materials and Methods: Thirty-five adult severe COVID-19 patients were enrolled from two COVID-19 hospitals in Dhaka, Bangladesh. Clinical manifestation, comorbid conditions, medications, SARS-CoV-2 RT-PCR related cycle threshold (CT) value, hematology, biochemical parameters with SARS-CoV-2 specific IgG and IgM responses at enrollment were compared between the survivors and deceased participants. Results: Total 27 patients survived and 8 patients died within 3 months of disease onset. Deceased patients suffered longer from shortness of breath than the survived (p = 0.049). Among the severe cases, 62% of the deceased patients had multiple comorbid condition compared to 48% of those who survived. Interestingly, the anti-viral was initiated earlier among the deceased patients [median day of 1 (IQR: 0, 1.5) versus 6.5 (IQR: 6.25, 6.75)]. Most of the survivors (55%) received a combination of anticoagulant (p = 0.034). Liver enzymes, creatinine kinase, and procalcitonin were higher among the deceased patients during enrollment. The median CT value among the deceased was significantly lower than the survivors (p = 0.025). A significant difference for initial IgG (p = 0.013) and IgM (p = 0.030) responses was found between the survivor and the deceased groups. Conclusions: The factors including older age, male gender, early onset of respiratory distress, multiple comorbidities, low CT value, and poor antibody response may contribute to the fatal outcome in severe COVID-19 patients. Early initiation of anti-viral and a combination of anticoagulant treatment may prevent or lower the fatality among severe COVID-19 cases.


Assuntos
COVID-19 , Adulto , Humanos , Masculino , SARS-CoV-2 , Estudos Prospectivos , Bangladesh/epidemiologia , Antivirais , Anticoagulantes , Imunoglobulina G , Imunoglobulina M
7.
Environ Monit Assess ; 194(10): 730, 2022 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-36066693

RESUMO

Nanomaterials (NMs) are currently being used in agricultural soils as part of a new bioremediation (BR) process. In this study, we reviewed the biosynthesis of NMs, as well as their chemical composition and prospective strategies for helpful and sustainable agricultural soil bioremediation (BR). Different types of NMs, such as nanoparticles, nanocomposites, nanocrystals, nano-powders, and nanotubes, are used in agricultural soil reclamation, and they reflect the toxicity of NMs to microorganisms. Plants (Sargassum muticum, Dodonaea viscose, Aloe Vera, Rosemarinus officinalis, Azadirachta indica, Green tea, and so on) and microorganisms (Escherichia coli, Shewanella oneidensis, Pleurotus sp., Klebsiella oxytoca, Aspergillus clavatus, and so on) are the primary sources for the biosynthesis of NMs. By using the BR process, microorganisms, such as bacteria and plants, can immobilize metals and change both inorganic and organic contaminants in the soil. Combining NMs with bioremediation techniques for agricultural soil remediation will be a valuable long-term solution.


Assuntos
Nanoestruturas , Poluentes do Solo , Biodegradação Ambiental , Monitoramento Ambiental , Plantas , Estudos Prospectivos , Solo/química , Poluentes do Solo/análise
8.
BMC Infect Dis ; 21(1): 1139, 2021 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-34743683

RESUMO

BACKGROUND: The alarming rise in multi-drug resistant (MDR) zoonotic pathogens, including Campylobacter spp., has been threatening the health sector globally. In Bangladesh, despite rapid growth in poultry sector little is known about the potential risks of zoonotic pathogens in homestead duck flocks. The aim of this study was to understand the occurrence, species diversity, and multi-drug resistance in Campylobacter spp., and identify the associated risk factors in duck farms in Bangladesh. METHODS: The study involved 20 duck farms at 6 sub-districts of Mymensingh, Bangladesh. Monthly occurrence of Campylobacter spp. in potential sources at the farms during February-September, 2018, was detected by culture and PCR-based methods. Campylobacter isolates were examined for resistance to different antimicrobials. Risk factors, concerning climatic and environmental disposition, farm management, and anthropogenic practices, of Campylobacter infection were estimated by participatory epidemiological tools. RESULTS: Occurrence of Campylobacter spp. was detected in overall 36.90% (155/420) samples, more frequently in drinking water (60%, 30/50), followed by cloacal swab (37.50%, 75/200), egg surface swab (35%, 35/100) and soil of the duck resting places (30%, 15/50) but was not detected in feed samples (n = 20). PCR assays distinguished the majority (61.30%, 95/155) of the isolates as C. coli, while the rest (38.70%, 60/155) were C. jejuni. Notably, 41.7% (25/60) and 31.6% (30/95) strains of C. jejuni and C. coli, respectively, were observed to be MDR. The dynamics of Campylobacter spp., distinctly showing higher abundance during summer and late-monsoon, correlated significantly with temperature, humidity, and rainfall, while sunshine hours had a negative influence. Anthropogenic management-related factors, including, inadequate hygiene practices, use of untreated river water, wet duck shed, flock age (1-6 months), and unscrupulous use of antimicrobials were identified to enhance the risk of MDR Campylobacter infection. CONCLUSION: The present study clearly demonstrates that duck farms contribute to the enhanced occurrence and spread of potentially pathogenic and MDR C. coli and C. jejuni strains and the bacterial dynamics are governed by a combined interaction of environmental and anthropogenic factors. A long-term holistic research at the environment-animal-human interface would be integral to divulge health risk reduction approaches tackling the spread of Campylobacter spp. from duck farms.


Assuntos
Infecções por Campylobacter , Campylobacter coli , Campylobacter jejuni , Campylobacter , Doenças das Aves Domésticas , Animais , Bangladesh/epidemiologia , Campylobacter/genética , Infecções por Campylobacter/epidemiologia , Infecções por Campylobacter/veterinária , Galinhas , Resistência a Múltiplos Medicamentos , Patos , Fazendas , Humanos , Lactente , Doenças das Aves Domésticas/epidemiologia , Fatores de Risco
9.
Phytother Res ; 35(3): 1329-1344, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33047412

RESUMO

Nigella sativa seed and its active compounds have been historically recognized as an effective herbal panacea that can establish a balanced inflammatory response by suppressing chronic inflammation and promoting healthy immune response. The essential oil and other preparations of N. sativa seed have substantial therapeutic outcomes against immune disturbance, autophagy dysfunction, oxidative stress, ischemia, inflammation, in several COVID-19 comorbidities such as diabetes, cardiovascular disorders, Kawasaki-like diseases, and many bacterial and viral infections. Compelling evidence in the therapeutic efficiency of N. sativa along with the recent computational findings is strongly suggestive of combating emerged COVID-19 pandemic. Also, being an available candidate in nutraceuticals, N. sativa seed oil could be immensely potential and feasible to prevent and cure COVID-19. This review was aimed at revisiting the pharmacological benefits of N. sativa seed and its active metabolites that may constitute a potential basis for developing a novel preventive and therapeutic strategy against COVID-19. Bioactive compounds of N. sativa seed, especially thymiquinone, α-hederin, and nigellidine, could be alternative and promising herbal drugs to combat COVID-19. Preclinical and clinical trials are required to delineate detailed mechanism of N. sativa's active components and to investigate their efficacy and potency under specific pathophysiological conditions of COVID-19.


Assuntos
Tratamento Farmacológico da COVID-19 , Nigella sativa/química , Extratos Vegetais/farmacologia , Sementes/química , Benzoquinonas , Diabetes Mellitus/tratamento farmacológico , Suplementos Nutricionais , Humanos , Ácido Oleanólico/análogos & derivados , Pandemias , Saponinas
10.
Environ Dev Sustain ; 23(6): 9352-9366, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33041644

RESUMO

We performed a global analysis with data from 149 countries to test whether temperature can explain the spatial variability of the spread rate and mortality of COVID-19 at the global scale. We performed partial correlation analysis and linear mixed effect modelling to evaluate the association of the spread rate and motility of COVID-19 with maximum, minimum, average temperatures and diurnal temperature variation (difference between daytime maximum and night-time minimum temperature) and other environmental and socio-economic parameters. After controlling the effect of the duration since the first positive case, partial correlation analysis revealed that temperature was not related with the spatial variability of the spread rate of COVID-19 at the global scale. Mortality was negatively related with temperature in the countries with high-income economies. In contrast, diurnal temperature variation was significantly and positively correlated with mortality in the low- and middle-income countries. Taking the country heterogeneity into account, mixed effect modelling revealed that inclusion of temperature as a fixed factor in the model significantly improved model skill predicting mortality in the low- and middle-income countries. Our analysis suggests that warm climate may reduce the mortality rate in high-income economies, but in low- and middle-income countries, high diurnal temperature variation may increase the mortality risk.

11.
Gynecol Oncol ; 158(3): 590-596, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32680634

RESUMO

OBJECTIVE: The Onco E6™ Cervical Test, based on detection of the E6 oncoprotein of HPV 16 and 18 genotypes is evaluated as a screen for the early detection cervical neoplasia in resource-limited countries. METHODS: This prospective study from June 2018 to June 2019 evaluated 235 women aged 21-65 years, who came to Gynaecological Oncology Outpatient Department by VIA, cytology, E6 oncoprotein test and by colposcopy. Screen-positive women by any of the tests or women with suspicious findings were further evaluated by biopsy at colposcopy. The McNemar test was used to compare the performance of E6 oncoprotein test with other screening tests. RESULTS: The E6 oncoprotein positivity rate was 6.8% (n = 16) with 81.25% HPV 16 positive and 18.75% HPV 18 positive. Among VIA positive cases (n = 100), E6 oncoprotein was positive in 9% (p < .001). In histopathology confirmed chronic cervicitis, CIN I, CIN II, CIN III and invasive cervical cancer, E6 test was positive for 2.8%, 4.7%, 25%, 50% and 100% respectively. E6 oncoprotein test had the highest specificity and Positive Predictive Value (PPV; 97% and 75%) compared to VIA (42% and 18%), cytology (95% and 46%) and colposcopy (94% and 59%). Sensitivity of the E6 oncoprotein test for detection of CIN3+ was significantly higher than that of cytology (52% VS 25%) but lower than that of VIA (52% VS 74%). CONCLUSIONS: The HPV E6 oncoprotein test is highly specific and is an effective triage test to reduce colposcopy referrals for the large number of false positive test outcomes seen with VIA.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Proteínas Oncogênicas Virais/metabolismo , Proteínas Repressoras/metabolismo , Neoplasias do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/virologia , Adulto , Idoso , Biomarcadores Tumorais/metabolismo , Detecção Precoce de Câncer , Feminino , Papillomavirus Humano 16/isolamento & purificação , Papillomavirus Humano 16/metabolismo , Papillomavirus Humano 18/isolamento & purificação , Papillomavirus Humano 18/metabolismo , Humanos , Pessoa de Meia-Idade , Infecções por Papillomavirus/metabolismo , Infecções por Papillomavirus/virologia , Estudos Prospectivos , Neoplasias do Colo do Útero/metabolismo , Esfregaço Vaginal , Adulto Jovem , Displasia do Colo do Útero/diagnóstico , Displasia do Colo do Útero/metabolismo , Displasia do Colo do Útero/virologia
12.
BMC Health Serv Res ; 20(1): 465, 2020 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-32456706

RESUMO

BACKGROUND: Accurate and high-quality data are important for improving program effectiveness and informing policy. In 2009 Bangladesh's health management information system (HMIS) adopted the District Health Information Software, Version 2 (DHIS2) to capture real-time health service utilization data. However, routinely collected data are being underused because of poor data quality and reporting. We aimed to understand the facilitators and barriers to implementing DHIS2 as a way to retrieve meaningful and accurate data for reproductive, maternal, newborn, child, and adolescent health (RMNCAH) services. METHODS: This qualitative study was conducted in two districts of Bangladesh from September 2017 to 2018. Data collection included key informant interviews (n = 11), in-depth interviews (n = 23), and focus group discussions (n = 2). The study participants were involved with DHIS2 implementation from the community level to the national level. The data were analyzed thematically. RESULTS: DHIS2 could improve the timeliness and completeness of data reporting over time. The reported facilitating factors were strong government commitment, extensive donor support, and positive attitudes toward technology among staff. Quality checks and feedback loops at multiple levels of data gathering points are helpful for minimizing data errors. Introducing a dashboard makes DHIS2 compatible to use as a monitoring tool. Barriers to effective DHIS2 implementation were lack of human resources, slow Internet connectivity, frequent changes to DHIS2 versions, and maintaining both manual and electronic system side-by-side. The data in DHIS2 remains incomplete because it does not capture data from private health facilities. Having two parallel HMIS reporting the same RMNCAH indicators threatens data quality and increases the reporting workload. CONCLUSION: The overall insights from this study are expected to contribute to the development of effective strategies for successful DHIS2 implementation and building a responsive HMIS. Focused strategic direction is needed to sustain the achievements of digital data culture. Periodic refresher trainings, incentives for increased performance, and an automated single reporting system for multiple stakeholders could make the system more user-friendly. A national electronic health strategy and implementation framework can facilitate creating a culture of DHIS2 use for planning, setting priorities, and decision making among stakeholder groups.


Assuntos
Coleta de Dados/métodos , Sistemas de Informação em Saúde , Serviços de Saúde/estatística & dados numéricos , Software , Bangladesh , Confiabilidade dos Dados , Grupos Focais , Humanos , Pesquisa Qualitativa
13.
J Environ Manage ; 255: 109861, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31786436

RESUMO

This study aims to develop an empirical model from Landsat data series to monitor the water salinity of coastal Bangladesh efficiently. Such a model can substitute expensive conventional techniques for assessing remote water quality. A set of equations connecting sensors 5 TM and 8 OLI were generated using multiple regression analysis. Radiometric and atmospheric corrections were carried out to enhance the quality of satellite images. Total 13 compositions of different bands including blue, green and red were considered to find the Coefficient of Determination (r2) with the field level EC (electrical conductivity) values collected from 74 sampling locations. Salinity data mainly EC values of coastal water were collected from primary and secondary sources. Considering the r2 values, significant band compositions were identified and then employed to generate linear equations. Such equation for Landsat 5 TM could detect water salinity (i.e. EC) accurately of around 82%. Similarly, the r2 value for Landsat 8 OLI was found as 0.76 that can confirm the applicability of Landsat data series to detect the change of salinity level of coastal water for a long period. The availability of coastal water was delineated by NDWI whereas salinity level was assessed using the developed equations for the year 2001 and 2019. Interestingly, it was observed that coastal areas having lower level of EC almost vanished whereas those of having higher level of EC were increased significantly between 2001 and 2019. Such increase in coastal water salinity is the result of combined effects of climatic and anthropogenic factors, which can pose a considerable risk to the coastal inhabitants including freshwater scarcity, food insecurity, and health hazard.


Assuntos
Salinidade , Água , Bangladesh , Monitoramento Ambiental , Água Doce , Qualidade da Água
14.
J Environ Sci Health B ; 55(12): 1061-1068, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32960146

RESUMO

Veterinary antibiotics (VAs) have entered the ecosystem principally through the application of organic fertilizer. However, factors influencing the contributions made by the prescribers and users thereof with respect to VAs in poultry manure have not been investigated. The purpose of this paper, therefore, is to identify factors associated with the VA prescription and usage as well as to measure the residual concentration along with the ecological risk of common VAs in poultry litter in Bangladesh. Structured questionnaire surveys were conducted so as to provide an understanding the perspective of prescribers and farmers. Ciprofloxacin (CIP), enrofloxacin (ENR), oxytetracycline (OTC), and doxycycline (DOX) were screened through the use of thin-layer chromatography (TLC) and quantified through high-performance liquid chromatography (HPLC). Also, methods of risk quotient (RQ) were applied to assess ecotoxicity. Most VAs were prescribed without a confirmatory diagnosis. The residue of CIP was dominant with a high concentration, followed by OTC but with a low concentration. A high ecological risk was associated with the use of OTC and DOX whereas the risk associated with the use of CIP and ENR was insignificant to low. The study highlights prescriber and user factors along with the variable ecological risk of VAs in litter.


Assuntos
Antibacterianos/análise , Uso de Medicamentos/estatística & dados numéricos , Esterco/análise , Aves Domésticas , Drogas Veterinárias/análise , Animais , Antibacterianos/toxicidade , Bangladesh , Cromatografia Líquida de Alta Pressão , Cromatografia em Camada Fina , Ciprofloxacina/análise , Estudos Transversais , Doxiciclina/análise , Ecotoxicologia/métodos , Enrofloxacina/análise , Fazendeiros , Medição de Risco , Poluentes do Solo/análise
15.
BMC Genomics ; 20(1): 98, 2019 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-30704415

RESUMO

BACKGROUND: Protein secretion is an essential process in all eukaryotes including organisms belonging to the phylum Apicomplexa, which includes many intracellular parasites. The apicomplexan parasites possess a specialized collection of secretory organelles that release a number of proteins to facilitate the invasion of host cells and some of these proteins also participate in immune evasion. Like in other eukaryotes, these parasites possess a series of membrane-bound compartments, namely the endoplasmic reticulum (ER), the intermediate compartments (IC) or vesicular tubular clusters (VTS) and Golgi complex through which proteins pass in a sequential and vectorial fashion. Two sets of proteins; COPI and COPII are important for directing the sequential transfer of material between the ER and Golgi complex. RESULTS: Here, using in silico approaches, we identify the components of COPI and COPII complexes in the genome of apicomplexan organisms. The results showed that the COPI and COPII protein complexes are conserved in most apicomplexan genomes with few exceptions. Diversity among the components of COPI and COPII complexes in apicomplexan is either due to the absence of a subunit or due to the difference in the number of protein domains. For example, the COPI epsilon subunit and COPII sec13 subunit is absent in Babesia bovis, Theileria parva, and Theileria annulata genomes. Phylogenetic and domain analyses for all the proteins of COPI and COPII complexes was performed to predict their evolutionary relationship and functional significance. CONCLUSIONS: The study thus provides insights into the apicomplexan COPI and COPII coating machinery, which is crucial for parasites secretory network needed for the invasion of host cells.


Assuntos
Apicomplexa/metabolismo , Complexo I de Proteína do Envoltório/metabolismo , Evolução Molecular , Genoma de Protozoário , Infecções por Protozoários/parasitologia , Proteínas de Protozoários/metabolismo , Apicomplexa/genética , Apicomplexa/isolamento & purificação , Complexo I de Proteína do Envoltório/genética , Humanos , Anotação de Sequência Molecular , Filogenia , Domínios e Motivos de Interação entre Proteínas , Subunidades Proteicas , Transporte Proteico , Infecções por Protozoários/genética , Infecções por Protozoários/metabolismo , Proteínas de Protozoários/genética
16.
Funct Integr Genomics ; 17(2-3): 279-292, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-27730426

RESUMO

Drought is one of the major abiotic stresses reducing crop yield. Since the discovery of plant microRNAs (miRNAs), considerable progress has been made in clarifying their role in plant responses to abiotic stresses, including drought. miR827 was previously reported to confer drought tolerance in transgenic Arabidopsis. We examined barley (Hordeum vulgare L. 'Golden Promise') plants over-expressing miR827 for plant performance under drought. Transgenic plants constitutively expressing CaMV-35S::Ath-miR827 and drought-inducible Zm-Rab17::Hv-miR827 were phenotyped by non-destructive imaging for growth and whole plant water use efficiency (WUEwp). We observed that the growth, WUEwp, time to anthesis and grain weight of transgenic barley plants expressing CaMV-35S::Ath-miR827 were negatively affected in both well-watered and drought-treated growing conditions compared with the wild-type plants. In contrast, transgenic plants over-expressing Zm-Rab17::Hv-miR827 showed improved WUEwp with no growth or reproductive timing change compared with the wild-type plants. The recovery of Zm-Rab17::Hv-miR827 over-expressing plants also improved following severe drought stress. Our results suggest that Hv-miR827 has the potential to improve the performance of barley under drought and that the choice of promoter to control the timing and specificity of miRNA expression is critical.


Assuntos
Adaptação Fisiológica , Secas , Hordeum/genética , Plantas Geneticamente Modificadas
17.
Plant Cell Environ ; 40(1): 11-24, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27155357

RESUMO

Drought is a crucial environmental constraint limiting crop production in many parts of the world. microRNA (miRNA) based gene regulation has been shown to act in several pathways, including crop response to drought stress. Sequence based profiling and computational analysis have revealed hundreds of miRNAs and their potential targets in different plant species under various stress conditions, but few have been biologically verified. In this study, 11 candidate miRNAs were tested for their expression profiles in barley. Differences in accumulation of only four miRNAs (Ath-miR169b, Osa-miR1432, Hv-miRx5 and Hv-miR166b/c) were observed between drought-treated and well-watered barley in four genotypes. miRNA targets were predicted using degradome analysis of two, different genotypes, and genotype-specific target cleavage was observed. Inverse correlation of mature miRNA accumulation with miRNA target transcripts was also genotype dependent under drought treatment. Drought-responsive miRNAs accumulated predominantly in mesophyll tissues. Our results demonstrate genotype-specific miRNA regulation under drought stress and evidence for their role in mediating expression of target genes for abiotic stress response in barley.


Assuntos
Secas , Perfilação da Expressão Gênica , Hordeum/genética , Hordeum/fisiologia , MicroRNAs/genética , Estresse Fisiológico/genética , Sequência de Bases , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Genótipo , Hordeum/citologia , MicroRNAs/metabolismo , Folhas de Planta/citologia , Folhas de Planta/genética , Estabilidade de RNA/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Reprodutibilidade dos Testes
18.
Environ Monit Assess ; 189(11): 565, 2017 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-29039035

RESUMO

Change analysis of land use and land cover (LULC) is a technique to study the environmental degradation and to control the unplanned development. Analysis of the past changing trend of LULC along with modeling future LULC provides a combined opportunity to evaluate and guide the present and future land use policy. The southwest coastal region of Bangladesh, especially Assasuni Upazila of Satkhira District, is the most vulnerable to natural disasters and has faced notable changes in its LULC due to the combined effects of natural and anthropogenic causes. The objectives of this study are to illustrate the temporal dynamics of LULC change in Assasuni Upazila over the last 27 years (i.e., between 1989 and 2015) and also to predict future land use change using CA-ANN (cellular automata and artificial neural network) model for the year 2028. Temporal dynamics of LULC change was analyzed, employing supervised classification of multi-temporal Landsat images. Then, prediction of future LULC was carried out by CA-ANN model using MOLUSCE plugin of QGIS. The analysis of LULC change revealed that the LULC of Assasuni had changed notably during 1989 to 2015. "Bare lands" decreased by 21% being occupied by other land uses, especially by "shrimp farms." Shrimp farm area increased by 25.9% during this period, indicating a major occupational transformation from agriculture to shrimp aquaculture in the study area during the period under study. Reduction in "settlement" area revealed the trend of migration from the Upazila. The predicted LULC for the year 2028 showed that reduction in bare land area would continue and 1595.97 ha bare land would transform into shrimp farm during 2015 to 2028. Also, the impacts of the changing LULC on the livelihood of local people and migration status of the Upazila were analyzed from the data collected through focus group discussions and questionnaire surveys. The analysis revealed that the changing LULC and the occupational shift from paddy cultivation to shrimp farming were related to each other. Around 31.3% of the total respondents stated that at least one of their family members had migrated. Climate-driven southwestern coastal people usually migrate from the vulnerable rural areas towards the nearest relatively safe city due to adverse effects of natural disasters. To control the unplanned development and reduce the internal migration in Assasuni and other coastal areas, a comprehensive land use management plan was suggested that would accommodate the diversified uses of coastal lands and eventually lessen the threats to the life and livelihood of the local people.


Assuntos
Agricultura/métodos , Conservação dos Recursos Naturais/métodos , Monitoramento Ambiental/métodos , Bangladesh , Cidades , Clima , Pesqueiros , Crescimento Demográfico , Imagens de Satélites
19.
Eukaryot Cell ; 14(6): 554-63, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25841021

RESUMO

Secreted proteins are the frontline between the host and pathogen. In mammalian hosts, secreted proteins enable invasive infection and can modulate the host immune response. Cryptococcosis, caused by pathogenic Cryptococcus species, begins when inhaled infectious propagules establish to produce pulmonary infection, which, if not resolved, can disseminate to the central nervous system to cause meningoencephalitis. Strains of Cryptococcus species differ in their capacity to cause disease, and the mechanisms underlying this are not well understood. To investigate the role of secreted proteins in disease, we determined the secretome for three genome strains of Cryptococcus species, including a hypovirulent and a hypervirulent strain of C. gattii and a virulent strain of C. neoformans. Sixty-seven unique proteins were identified, with different numbers and types of proteins secreted by each strain. The secretomes of the virulent strains were largely limited to proteolytic and hydrolytic enzymes, while the hypovirulent strain had a diverse secretome, including non-conventionally secreted canonical cytosolic and immunogenic proteins that have been implicated in virulence. The hypovirulent strain cannot establish pulmonary infection in a mouse model, but strains of this genotype have caused human meningitis. To directly test brain infection, we used intracranial inoculation and found that the hypovirulent strain was substantially more invasive than its hypervirulent counterpart. We suggest that immunogenic proteins secreted by this strain invoke a host response that limits pulmonary infection but that there can be invasive growth and damage if infection reaches the brain. Given their known role in virulence, it is possible that non-conventionally secreted proteins mediate this process.


Assuntos
Cryptococcus neoformans/patogenicidade , Proteínas Fúngicas/metabolismo , Meningite Criptocócica/microbiologia , Via Secretória , Animais , Cryptococcus neoformans/genética , Cryptococcus neoformans/metabolismo , Proteínas Fúngicas/genética , Camundongos , Peptídeo Hidrolases/genética , Peptídeo Hidrolases/metabolismo , Virulência/genética
20.
BMC Complement Altern Med ; 16: 242, 2016 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-27457362

RESUMO

BACKGROUND: Present study has been conducted to know the anthelmintic activity of polyaniline coated silver nanoparticles (AgNPs) synthesized from Momordica charantia fruit extract. METHODS: By reduction of AgNO3 in presence of NaBH4, silver nanoparticles were prepared. After mixing silver nanoparticles and extracts, coating was given on nanoparticles using polyaniline. Prepared nanoparticles were characterized by Visual, UV, FTIR spectroscopy, SEM techniques, and TEM analysis. RESULTS: The FTIR results implied that AgNPs were successfully synthesized and capped with bio-compounds present in the extract. The result showed that death times of worm were 35.12 ± 0.5 and 59.3 ± 0.3 minutes for M. charantia extract and Ag-nanoparticles individually. But when these two combined together, paralysis and death time fall drastically which were only 6.16 ± 0.6 and 9.1 ± 0.4 minutes respectively. Albendazole tablet was used as standard, which made worms death in 3.66 ± 0.1 minutes. CONCLUSION: Ag-Extract NPs showed strong anthelmintic activity against worm. This study has paved the way for further research to design new anthelmintic drug from the combination of M. charantia and AgNPs.


Assuntos
Anti-Helmínticos/farmacologia , Nanopartículas Metálicas/química , Momordica charantia/química , Extratos Vegetais/farmacologia , Prata/farmacologia , Animais , Anti-Helmínticos/química , Frutas/química , Oligoquetos/efeitos dos fármacos , Extratos Vegetais/química , Prata/química
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