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1.
ACS Omega ; 6(46): 31348-31357, 2021 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-34841178

RESUMO

Triazole is an imperative heterocycle renowned for its broad-spectrum biological significance. In this manuscript, facile microwave-assisted synthesis of a series of 4-(benzylideneamino)-3-(1-(2-fluoro-[1,1'-biphenyl]-4-yl)ethyl)-1H-1,2,4-triazole-5(4H)-thione 6(a-m) derivatives along with their in vivo analgesic activity is reported. 2-(2-Fluoro-[1,1'-biphenyl]-4-yl)propanoic acid (flurbiprofen) was converted to methyl 2-(2-fluoro-[1,1'-biphenyl]-4-yl)propanoate using microwave irradiation, followed by its hydrazinolysis with hydrazine monohydrate. 2-(2-Fluoro-[1,1'-biphenyl]-4-yl)propanehydrazide thus obtained was converted to 4-amino-3-(1-(2-fluoro-[1,1'-biphenyl]-4-yl)ethyl)-1H-1,2,4-triazole-5(4H)-thione, followed by its condensation with different aromatic aldehydes to get the title compounds. Structures of all the synthesized compounds were established using different methods (1H NMR and 13C NMR spectroscopies, mass spectrometry, and elemental analysis) and evaluated for their potential as analgesic agents by tail flick, hot plate, and writhing methods. The results of this in vivo study revealed several compounds as potent analgesic agents among which compound 6e showed significant analgesic effect for all the three assays employed.

2.
Environ Sci Pollut Res Int ; 28(9): 10474-10487, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33411303

RESUMO

Electronic waste is termed as e-waste and on recycling it produces environmental pollution. Among these e-waste pollutants, polychlorinated biphenyls (PCBs) are significantly important due to ubiquitous, organic in nature and serious health and environmental hazards. PCBs are used in different electrical equipment such as in transformers and capacitors for the purposes of exchange of heat and hydraulic fluids. Bioremediation is a reassuring technology for the elimination of the PCBs from the environment. In spite of their chemical stability, there are several microbes which can bio-transform or mineralize the PCBs aerobically or anaerobically. In this review paper, our objective was to summarize the information regarding PCB-degrading enzymes and microbes. The review suggested that the most proficient PCB degraders during anaerobic condition are Dehalobacter, Dehalococcoides, and Desulfitobacterium and in aerobic condition are Burkholderia, Achromobacter, Comamonas, Ralstonia, Pseudomonas, Bacillus, and Alcaligenes etc., showing the broadest substrate among bacterial strains. Enzymes found in soil such as dehydrogenases and fluorescein diacetate (FDA) esterases have the capability to breakdown PCBs. Biphenyl upper pathway involves four enzymes: dehydrogenase (bphB), multicomponent dioxygenase (bphA, E, F, and G), second dioxygenase (bphC), hydrolase, and (bphD). Biphenyl dioxygenase is considered as the foremost enzyme used for aerobic degradation of PCBs in metabolic pathway. It has been proved that several micro-organisms are responsible for the PCB metabolization. The review provides novel strategies for e-waste-contaminated soil management.


Assuntos
Resíduo Eletrônico , Bifenilos Policlorados , Poluentes do Solo , Biodegradação Ambiental , Bifenilos Policlorados/análise , Microbiologia do Solo , Poluentes do Solo/análise
4.
Indoor Air ; 31(3): 807-817, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33247439

RESUMO

This preliminary investigation highlights the occurrence of organochlorine pesticides (OCPs) in the indoor environment of a megacity, Lahore, Pakistan using the dust ensnared by air-conditioner filters. The Σ16 OCPs concentration ranged from 7.53 to 1272.87 ng/g with the highest percent contribution by ΣDDT (dichlorodiphenyltrichloroethane; 87.21%) and aldrin (6.58%). The spatial variation of OCPs profile revealed relatively higher concentration from homes near to agricultural and abandoned DDT manufacturing sites. Calculated isomer ratios revealed historic sources of hexachlorocyclohexanes (HCHs) and the fresh input of technical DDT and chlordane by the dwellers. The air conditioner dust was helpful to better understand the health risk in the indoor environment. So far a high lifetime cancer risk (10-3 ) was predicted for toddlers via accidental ingestion, inhalation, and dermal exposure. Similarly, the non-carcinogenic risk-based hazard quotient was found to be high for toddlers (6.94) and within the permissible limit (<1) for adults.


Assuntos
Poluição do Ar em Ambientes Fechados , Poeira , Monitoramento Ambiental , Hidrocarbonetos Clorados/análise , Praguicidas/análise , Adulto , Agricultura , China , DDT , Países em Desenvolvimento , Hexaclorocicloexano , Produtos Domésticos , Humanos , Paquistão
5.
Environ Sci Pollut Res Int ; 27(7): 6837-6850, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31879876

RESUMO

This study assessed the polychlorinated biphenyl (PCB) levels in human milk and its associated health risk to infants from rural and urban settings of five districts of Punjab Province, Pakistan. The ∑34PCB concentrations ranged from 30.9 to 68.3 ng g-1 on lipid weight (l.w.) basis. The ∑8DL-PCB concentrations were ranged from 0.29 to 1.35 ng g-1 l.w., (mean 6.2 ± 8.7 ng g-1 l.w.), with toxicity equivalent to polychlorinated dibenzodioxins (PCDDs) ranging from 8.58 × 10-6 to 0.05 ng TEQ g-1 l.w. The spatial trend of PCB levels in human milk revealed higher bioaccumulative levels for urban mothers as compared with rural counterparts. The estimated daily intake (EDI) values of DL-PCBs to infants through trans-mammary transfer were considerably higher than tolerable daily intake limits established by WHO (i.e., 1-4 pg TEQ kg-1 bw) and other globally recognized organizations. Similarly, the hazard quotient values for TEQ ∑8DL-PCBs (range 1.21 to 79.87) were far above the benchmark value of 1 at all the sampling sites, indicating the high levels of adverse health risks to infants in the region through breast milk consumption. The ∑34PCB levels were found to be negatively correlated with mother' age (r = -0.31; p = 0.02), parity (r = - 0.85; p = 0.001), and infant' birth weight (r = - 0.73; p = 0.01). The present study suggests undertaking comprehensive public health risk assessment studies and firm regulatory measures to safeguard human health risks.


Assuntos
Exposição Ambiental/estatística & dados numéricos , Poluentes Ambientais/metabolismo , Leite Humano/metabolismo , Bifenilos Policlorados/metabolismo , Benzofuranos , Dibenzofuranos Policlorados , Feminino , Humanos , Índia , Lactente , Paquistão , Gravidez
6.
Chem Pharm Bull (Tokyo) ; 67(11): 1191-1200, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31685748

RESUMO

An environment friendly synthesis of novel hybrid pharmacophores derived from synergism of nalidixic acid and 1,3-diphenylprop-2-en-1-ones is described. Percent yield and reaction times of microwave assisted reactions have been compared with the reactions carried out under conventional reaction conditions which show marked decrease in reaction times and significant increase in yields. Besides, anti-oxidant potential of the synthesized hybrid compounds was evaluated and some of the compounds showed marked ascorbic acid equivalence Ferric reducing anti-oxidant power (FRAP) and metal chelating capacities. Crystal study of one representative of the synthesized series is also presented.


Assuntos
Antioxidantes/farmacologia , Naftiridinas/farmacologia , Antioxidantes/síntese química , Antioxidantes/química , Cristalografia por Raios X , Relação Dose-Resposta a Droga , Micro-Ondas , Modelos Moleculares , Estrutura Molecular , Naftiridinas/síntese química , Naftiridinas/química , Relação Estrutura-Atividade
7.
Environ Sci Technol ; 53(10): 5596-5604, 2019 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-31033281

RESUMO

About 20 million rural Bangladeshis continue to drink well water containing >50 µg/L arsenic (As). This analysis argues for reprioritizing interventions on the basis of a survey of wells serving a population of 380,000 conducted one decade after a previous round of testing overseen by the government. The available data indicate that testing alone reduced the exposed population in the area in the short term by about 130,000 by identifying the subset of low As wells that could be shared at a total cost of 150 m) wells and a single piped-water supply system by the government reduced exposure of little more than 7000 inhabitants at a cost of US$150 per person whose exposure was reduced. The findings make a strong case for long-term funding of free well testing on a massive scale with piped water or groundwater treatment only as a last resort.


Assuntos
Arsênio , Água Subterrânea , Poluentes Químicos da Água , Bangladesh , Humanos , Abastecimento de Água
8.
PLoS Curr ; 102018 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-30210935

RESUMO

INTRODUCTION: Chikungunya is an incipient disease, caused by Chikungunya virus (CHKV) that belongs to genus alphavirus of the family Togaviridae. MATERIALS AND METHODS: In this study, during an outbreak of CHKV in Dec 2016 in Karachi, Pakistan, samples were collected from patients presenting with fever, tiredness and pain in muscles and joints. Total 126 sera were tested for the presence of Chikungunya infection through ELISA and Real-time Reverse Transcriptase PCR assay. RESULTS AND DISCUSSION: This study showed that approx 79.4% samples were positive for CHKV. To our knowledge, this is the first reported outbreak from last decades in which the presence of CHKV is confirmed in Karachi while affecting such large no. of individuals.. CONCLUSION: CHKV diagnosis should be considered by the scientists and clinicians as a differential diagnosis in febrile patients, and appropriate control strategies must be adopted for its surveillance.

9.
Virol Sin ; 32(6): 520-532, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29243070

RESUMO

Chikungunya virus (CHIKV) is a mosquito-borne virus that causes epidemics widely in the world especially in the tropical and subtropical regions. Phylogenetic analysis has found that the CHIKV lineages were associated with the spatial and temporal distributions, which were related to the virus adaption to the major mosquito species and their distributions. In this study, we reported the complete genome sequences of eight CHIKV isolates from the outbreak in Pakistan last year. Then we reviewed the evolutionary history using extensive phylogenetic analysis, analyzed lineage-specific substitutions in viral proteins, and characterized the spreading pathway of CHIKV strains including the Pakistani strains. The results showed that the Pakistani stains belonged to the ECSA.IOL sub-lineage and derived from India. The genetic properties of the Pakistani strains including the adaptive substitution to vectors were further characterized, and the potential risks from the occurrence of CHIKV infection in Pakistan were discussed. These results provided better understanding of CHIKV evolution and transmission in the world and revealed the possible origination of the CHIKV outbreak and epidemic in Pakistan, which would promote the disease prevention and control in the identified countries and territories with the history of CHIKV infections as well as new regions with potential risk of CHIKV outbreaks.


Assuntos
Febre de Chikungunya/epidemiologia , Febre de Chikungunya/virologia , Vírus Chikungunya/classificação , Vírus Chikungunya/genética , Epidemias , Evolução Molecular , Adaptação Biológica , Substituição de Aminoácidos , Vírus Chikungunya/isolamento & purificação , Genoma Viral , Genótipo , Índia , Epidemiologia Molecular , Paquistão/epidemiologia , Filogenia , Análise de Sequência de DNA
10.
Virol Sin ; 32(6): 511-519, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29285673

RESUMO

The chikungunya virus (CHIKV) is a mosquito-transmitted alphavirus, which has infected millions of people in Africa, Asia, Americas, and Europe since it reemerged in India and Indian Ocean regions in 2005-2006. Starting in the middle of November 2016, CHIKV has been widely spread, and more than 4,000 cases of infections in humans were confirmed in Pakistan. Here, we report the first isolation and characterization of CHIKV from the Pakistan outbreak. Eight CHIKV strains were newly isolated from human serum samples using a cell culture procedure. A full-length genome sequence and eight complete envelope (E1) sequences of CHIKV from Pakistan were obtained in this study. Alignment of the CHIKV E1 sequences revealed that the eight new CHIKV isolates were highly homogeneous, with only two nonsynonymous substitutions found at generally conserved sites (E99 and Q235). Based on the comparison of 342 E1 sequences, the two nonsynonymous mutations were located in well-recognized domains associated with viral functions such as the cell fusion and vector specificity, suggesting their potential functional importance. Phylogenetic analysis indicated that the CHIKV strains from Pakistan originated from CHIKV circulating in the Indian region. This study helps elucidate the epidemics of CHIKV in Pakistan and also provides a foundation for studies of evolution and expansion of CHIKV in South Asia.


Assuntos
Febre de Chikungunya/epidemiologia , Febre de Chikungunya/virologia , Vírus Chikungunya/genética , Vírus Chikungunya/isolamento & purificação , Surtos de Doenças , Adolescente , Adulto , Idoso , Substituição de Aminoácidos , Análise por Conglomerados , Feminino , Genoma Viral , Humanos , Masculino , Pessoa de Meia-Idade , Mutação de Sentido Incorreto , Paquistão/epidemiologia , Filogenia , Análise de Sequência de DNA , Homologia de Sequência , Soro/virologia , Proteínas do Envelope Viral/genética , Cultura de Vírus , Adulto Jovem
11.
Environ Toxicol Chem ; 36(5): 1193-1201, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-27684504

RESUMO

The present study was conducted to highlight the existing level of organochlorine-pesticides (OCPs) from human milk (n = 45) and blood serum (n = 40) of female workers who pick cotton in Khanewal District, southern Punjab, Pakistan. Source apportionment, congener-specific analysis, and risk surveillance of OCPs are reported from human milk and blood samples. Levels of OCPs in milk and blood serum samples ranged from 15.7 ppb to 538.3 ppb and from 16.4 ppb to 747.1 ppb, respectively, and were lower than previously published reports from other regions of the globe. Congener-specific analysis revealed that DDTs were predominant, followed by hexachlorocyclohexane, chlordane, and hexachlorobenzene. Calculated results for source apportionment analysis suggested that contamination load was a new input of DDTs as well as the historic use of lindane in the study area. Levels of OCPs in milk and blood serum were significantly (p < 0.05) correlated with age, time period of picking cotton, and number of children. Health risk revealed that female workers had risk of cancer among 1 per million; however, noncarcinogenic risks were not considerable. Environ Toxicol Chem 2017;36:1193-1201. © 2016 SETAC.


Assuntos
Gossypium/química , Praguicidas/análise , Adolescente , Adulto , DDT/análise , DDT/sangue , Monitoramento Ambiental , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Hexaclorobenzeno/análise , Hexaclorobenzeno/sangue , Humanos , Leite Humano/química , Paquistão , Praguicidas/sangue , Análise de Componente Principal , Risco , Adulto Jovem
12.
Biomed Res Int ; 2016: 6126385, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27446955

RESUMO

The objective of this study was to assess the occupational exposure to mercury in dentistry and associated environmental emission in wastewater of Lahore, Pakistan. A total of ninety-eight blood samples were collected comprising 37 dentists, 31 dental assistants, and 30 controls. Results demonstrate that the dentistry personnel contained significantly higher mean concentration of mercury in their blood samples (dentists: 29.835 µg/L and dental assistants: 22.798 µg/L) compared to that of the controls (3.2769 µg/L). The mean concentration of mercury was found maximum in the blood samples of older age group (62.8 µg/L) in dentists and (44.3 µg/L) in dental assistants. The comparison of mercury concentration among dentists, dental assistants, and controls (pairing based on their ages) revealed that the concentration increased with the age and experience among the dentists and dental assistants. Moreover, the mercury concentration in all the studied dental wastewater samples, collected from twenty-two dental clinics, was found to be exceeding the recommended discharge limit of 0.01 mg/L. Therefore, we recommend that immediate steps must be taken to ensure appropriate preventive measures to avoid mercury vapors in order to prevent potential health hazards to dentistry personnel. Strong regulatory and administrative measures are needed to deal with mercury pollution on emergency basis.


Assuntos
Amálgama Dentário/análise , Assistentes de Odontologia/estatística & dados numéricos , Odontólogos/estatística & dados numéricos , Mercúrio/sangue , Exposição Ocupacional/estatística & dados numéricos , Poluição Química da Água/estatística & dados numéricos , Distribuição por Idade , Competência Clínica/estatística & dados numéricos , Resíduos Odontológicos/análise , Resíduos Odontológicos/estatística & dados numéricos , Feminino , Humanos , Masculino , Paquistão/epidemiologia , Prata/sangue , Águas Residuárias/análise , Águas Residuárias/estatística & dados numéricos , Poluição Química da Água/análise
13.
Sci Total Environ ; 511: 354-61, 2015 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-25553549

RESUMO

To evaluate the screening level risk assessment of OCPs in rice (Oryza sativa L.) straw (n=20) and rice grains (n=20), samples were collected from different districts of Punjab Province, Pakistan. ∑OCPs' levels (ng g(-1)) in rice straw and grains ranged from 3.63 to 39.40, 2.72 to 49.89, respectively. DDTs were found predominant over the other detected OCP isomers followed by HCH and heptachlor. Results of one way ANOVA reflected no significant difference for OCPs' levels among sampling sites, except heptachlor for rice grains. ∑OCPs' concentration in rice straw samples was exceeding the minimal residual levels (MRLs) (Australian and Japanese). Results of dietary intake and risk assessment suggested that rice straw is not safe for animals to consume as fodder. Human health was suggested to have some carcinogenic risks by consumption of rice grains, however, no considerable hazardous risk (non-carcinogenic) to human health was found.


Assuntos
Agricultura , Hidrocarbonetos Clorados/análise , Oryza/química , Praguicidas/análise , Poluentes Químicos da Água/análise , Monitoramento Ambiental/métodos , Humanos , Paquistão , Medição de Risco/métodos
15.
Int J Phytoremediation ; 13(5): 410-20, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21598772

RESUMO

Adsorption is an environmental friendly process for removal and/or recovery of heavy metals from wastewater. In recent years, it has been substantiated as a popular technique to treat industrial waste effluents, with significant advantages. In this work, batchwise removal of chromium (III) ions from water by Polyalthia longifolia leaves was studied as a function of adsorbent dose, pH, contact time, and agitation speed. Surface characteristics of the leaves were evaluated by recording IR spectra. The Langmuir, Freundlich, and Temkin adsorption isotherms were employed to explain the sorption process. It was found that one gram of leaves can remove 1.87 mg of trivalent chromium when working at pH 3.0. It has been concluded that Polyalthia longifolia leaves can be used as cost-effective and benign adsorbents for removal of Cr(III) ions from wastewater.


Assuntos
Cromo/metabolismo , Polyalthia/metabolismo , Poluentes Químicos da Água/metabolismo , Adsorção , Biomassa , Cromo/análise , Concentração de Íons de Hidrogênio , Resíduos Industriais , Modelos Químicos , Movimento (Física) , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Polyalthia/crescimento & desenvolvimento , Espectrofotometria Atômica , Espectroscopia de Infravermelho com Transformada de Fourier , Fatores de Tempo , Eliminação de Resíduos Líquidos , Poluentes Químicos da Água/análise , Purificação da Água
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