Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 5 de 5
Filtrar
Mais filtros








Base de dados
Intervalo de ano de publicação
1.
Chemosphere ; 286(Pt 3): 131978, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34426287

RESUMO

The present study dealt with the restricted microbial tolerance for lead and tin during bioleaching of waste printed circuit boards (WPCBs) and lower extraction yields of valuable metals. Pretreatment of WPCBs in 4.0 mol/L HNO3 at 90 °C for 180 min duration prominently dissolved the toxicant metals before the microbial mobilization of valuable metals. Acid pretreatment followed the first-order kinetics that exhibiting an intermediate-controlled mechanism with the apparent activation energy determined to be Ea(Pb), 25.1 kJ/mol and Ea(Sn), 21.9 kJ/mol. Thereafter, the parametric optimization of aeration rate, O2-enrichment, external CO2 supply, temperature, and time for bioleaching of ground WPCBs was examined using Sulfobacillus thermosulfidooxidans (strain RDB). A favourable condition for Cu-bioleaching under higher oxidative environment in comparison to Ni and Zn exhibited the auto-catalytic behaviour of Cu2+ in the biological system. More than 92% of valuable metals were extracted under the optimal condition of aeration rate, 0.5 L/min; O2-enrichement dosage, 30%; external CO2 supply, 0.1%; temperature, 55 °C; and time, 18 days. The bioleaching kinetics followed shrinking core model that exhibiting the shifting of mass transfer from chemically-controlled to the diffusion-controlled mechanism. This process offers two-fold advantages that restoring the valuable metals with low-emission biotechnological route for waste valorization.


Assuntos
Resíduo Eletrônico , Clostridiales , Resíduo Eletrônico/análise , Resíduos Perigosos , Cinética , Reciclagem
2.
Mamm Genome ; 32(6): 443-447, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34272576

RESUMO

CpG islands (CGIs) are aggregation of CpG dinucleotides in the promoters of mammalian genes. These CGIs are present in almost all the housekeeping genes and some tissue-specific genes in the mammalian genome. Extensive research has been done on the prevalence and role of CGIs in protein-coding genes. However, little is known about CGIs in pseudogenes. In the current research project, we focused on CGIs in three main classes of pseudogenes e.g., duplicated pseudogenes (DPGs), processed pseudogenes (PPGs), and unitary pseudogenes (UPGs). We discovered a predominant absence of CGIs in the promoters of all three pseudogenes. We also compared the CGI profile of these pseudogenes with their parent genes and found that unitary pseudogenes (UPGs) differ from the DPGs and PPGs in the sense that in the latter, lack of CGIs is a consequential event while in UPGs, this lack of CGIs in their promoters is not a result of pseudogenization process. We also discussed the implication of the results obtained from this comparison. To our knowledge, this is the first-ever study highlighting this aspect of UPGs throwing new insights into the evolution of genome in general and especially in the context of pseudogenes.


Assuntos
Genoma , Pseudogenes , Animais , Ilhas de CpG/genética , Metilação de DNA/genética , Humanos , Mamíferos/genética , Regiões Promotoras Genéticas , Pseudogenes/genética
3.
J Coll Physicians Surg Pak ; 29(6): 563-573, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31133158

RESUMO

Crimean-Congo hemorrhagic fever (CCHF) is one of the severe forms of high-fatality hemorrhagic fever transmitted by bite of infected ticks or body fluids of infected individuals. Lack of sufficient research and endemic potential of the disease is posing serious threats to public health. The aim of this review was to explore the current status of Crimean-Congo hemorrhagic fever virus (CCHFV) related research and to identify knowledge gaps and the areas that are yet to be explored. An interpretative scoping review methodology was followed to systematically characterize the most recent literature. Literature survey was conducted using electronic databases: PubMed, Scopus, ScienceDirect and Google Scholar. This comprehensive research yielded more than 300 records, but we excluded 100 articles based on our inclusion criteria and duplicates removal. All articles (n=85) that have been published currently were discussed in this scoping review. From a total of 303 documents retrieved, 85 met the criteria. All the documents (case studies, review articles, systematic reviews, meta-analysis, case control studies, cohort studies, randomised control trials, and longitudinal studies) were included in the study. The articles mainly cover different areas such as epidemiology, prevalence, diagnosis, pathogenesis, clinical outcomes, molecular basis, phylogenetics, transmission and treatment of CCHF. Treatment and prevention related knowledge is limited; therefore, future research should focus the development of therapeutics to mitigate the increasing risk of CCHF. Priority future goal should be studies on the molecular basis and treatment of CCHFV infection because several knowledge gaps have been identified in these areas.


Assuntos
Vírus da Febre Hemorrágica da Crimeia-Congo/genética , Vírus da Febre Hemorrágica da Crimeia-Congo/patogenicidade , Febre Hemorrágica da Crimeia , Carrapatos/virologia , Animais , Antivirais/uso terapêutico , Vetores Aracnídeos/virologia , Vírus da Febre Hemorrágica da Crimeia-Congo/classificação , Vírus da Febre Hemorrágica da Crimeia-Congo/isolamento & purificação , Febre Hemorrágica da Crimeia/diagnóstico , Febre Hemorrágica da Crimeia/tratamento farmacológico , Febre Hemorrágica da Crimeia/epidemiologia , Febre Hemorrágica da Crimeia/transmissão , Febre Hemorrágica da Crimeia/virologia , Humanos
4.
Viral Immunol ; 32(4): 192-194, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30939104

RESUMO

Hepatitis C virus (HCV) genotyping is a critical parameter that acts as predictor of treatment response. According to previously reported findings, about 11 million population of Pakistan are HCV infected. Accumulating data suggest that genotype is the most prevalent genotype and mixed and untypable genotypes are the least prevalent genotypes of HCV. We observed that overall prevalence of mixed genotype (5.03%) and untypable genotype (3.3%) of HCV is on constant rise. This study highlights that the emergence of novel quasispecies could be reason of treatment failure in patients receiving direct-acting antiviral drugs.


Assuntos
Genótipo , Hepacivirus/classificação , Hepacivirus/isolamento & purificação , Hepatite C Crônica/virologia , Técnicas de Genotipagem , Hepacivirus/genética , Hepatite C Crônica/epidemiologia , Humanos , Epidemiologia Molecular , Paquistão/epidemiologia , Prevalência
5.
Water Sci Technol ; 78(1-2): 147-155, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30101797

RESUMO

In the present study, biosorption behavior of a green filamentous alga, spirogyra in its native and modified states was investigated for copper removal from an electroplating industrial effluent. For this, the effluent containing 194 mg·L-1 Cu2+ in sulfate medium was contacted with both forms of spirogyra, under the parametric variations of effluent pH, adsorbent dosage, contact time, and sorption temperature. The study revealed spirogyra as a prominent candidate for removing contaminant metal cation; however, at the same condition, biosorption capacity of modified biomass in gel form was higher than the native spirogyra. At the optimized condition with 6 g sorbent dosage treated to 100 mL effluent for 30 min at pH 6.0 and temperature 20 °C, the maximum 82.8% and 96.4% copper could be adsorbed by the native and modified spirogyra, respectively. The batch sorption data using native biomass followed pseudo-first-order kinetic; exhibiting the multilayer sorption mechanism via surface diffusion could be defined by the Freundlich model. In contrast, the sulfuric acid treated modified spirogyra followed pseudo-second-order kinetics and intra particle diffusion as the rate-limiting step.


Assuntos
Cobre , Galvanoplastia , Resíduos Industriais/análise , Spirogyra/metabolismo , Adsorção , Biodegradação Ambiental , Biomassa , Cobre/isolamento & purificação , Cobre/metabolismo , Cinética , Temperatura
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA