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1.
J Infect Public Health ; 17(2): 271-282, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38134602

RESUMO

BACKGROUND: Typhoid fever, caused by Salmonella enterica serovar Typhi, is a significant public health concern due to the escalating of antimicrobial resistance (AMR), with limited treatment options for extensively drug-resistant (XDR) S. Typhi strains pose a serious threat to disease management and control. This study aimed to investigate the genomic characteristics, epidemiology and AMR genes of XDR S. Typhi strains from typhoid fever patients in Pakistan. METHODOLOGY: We assessed 200 patients with enteric fever symptoms, confirming 65 S. Typhi cases through culturing and biochemical tests. Subsequent antimicrobial susceptibility testing revealed 40 cases of extensively drug-resistant (XDR) and 25 cases of multi-drug resistance (MDR). Thirteen XDR strains were selected for whole-genome sequencing, to analyze their sequence type, phylogenetics, resistance genes, pathogenicity islands, and plasmid sequences using variety of data analysis resources. Pangenome analysis was conducted for 140 XDR strains, including thirteen in-house and 127 strains reported from other regions of Pakistan, to assess their genetic diversity and functional annotation. RESULTS: MLST analysis classified all isolates as sequence type 1 (ST-1) with 4.3.1.1. P1 genotype characterization. Prophage and Salmonella Pathogenicity Island (SPI) analysis identified intact prophages and eight SPIs involved in Salmonella's invasion and replication within host cells. Genome data analysis revealed numerous AMR genes including dfrA7, sul1, qnrS1, TEM-1, Cat1, and CTX-M-15, and SNPs associated with antibiotics resistance. IncY, IncQ1, pMAC, and pAbTS2 plasmids, conferring antimicrobial resistance, were detected in a few XDR S. Typhi strains. Phylogenetic analysis inferred a close epidemiological linkage among XDR strains from different regions of Pakistan. Pangenome was noted closed among these strains and functional annotation highlighted genes related to metabolism and pathogenesis. CONCLUSION: This study revealed a uniform genotypic background among XDR S. Typhi strains in Pakistan, signifying a persistence transmission of a single, highly antibiotic-resistant clone. The closed pan-genome observed underscores limited genetic diversity and highlights the importance of genomic surveillance for combating drug-resistant typhoid infections.


Assuntos
Salmonella typhi , Febre Tifoide , Humanos , Salmonella typhi/genética , Febre Tifoide/epidemiologia , Tipagem de Sequências Multilocus , Paquistão/epidemiologia , Filogenia , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico
2.
Pharmaceuticals (Basel) ; 16(6)2023 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-37375754

RESUMO

One homoleptic (1) and three heteroleptic (2-4) palladium(II) complexes were synthesized and characterized by various physicochemical techniques, i.e., elemental analysis, FTIR, Raman spectroscopy, 1H, 13C, and 31P NMR. Compound 1 was also confirmed by single crystal XRD, showing a slightly distorted square planar geometry. The antibacterial results obtained via the agar-well diffusion method for compound 1 were maximum among the screen compounds. All the compounds have shown good to significant antibacterial results against the tested bacterial strains, Escherichia coli, Klebsiella pneumonia, and Staphylococcus aureus, except 2 against Klebsiella pneumonia. Similarly, the molecular docking study of compound 3 has shown the best affinity with binding energy scores of -8.6569, -6.5716, and -7.6966 kcal/mol against Escherichia coli, Klebsiella pneumonia, and Staphylococcus aureus, respectively. Compound 2 has exhibited the highest activity (3.67 µM), followed by compound 3 (4.57 µM), 1 (6.94 µM), and 4 (21.7 µM) against the DU145 human prostate cancer cell line using the sulforhodamine B (SRB) method as compared to cisplatin (>200 µM). The highest docking score was obtained for compounds 2 (-7.5148 kcal/mol) and 3 (-7.0343 kcal/mol). Compound 2 shows that the Cl atom of the compound acts as a chain side acceptor for the DR5 receptor residue Asp B218 and the pyridine ring is involved in interaction with the Tyr A50 residue via arene-H, while Compound 3 interacts with the Asp B218 residue via the Cl atom. The physicochemical parameters determined by the SwissADME webserver revealed that no blood-brain barrier (BBB) permeation is predicted for all four compounds, while gastrointestinal absorption is low for compound 1 and high for the rest of the compounds (2-4). As concluding remarks based on the obtained in vitro biological results, the evaluated compounds after in vivo studies might be a good choice for future antibiotics and anticancer agents.

3.
Front Genet ; 13: 982527, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36579328

RESUMO

Introduction: Viral hemorrhagic septicemia virus (VHSV) is the most lethal pathogen in aquaculture, infecting more than 140 fish species in marine, estuarine, and freshwater environments. Viral hemorrhagic septicemia virus is an enveloped RNA virus that belongs to the family Rhabdoviridae and the genus Novirhabdovirus. The current study is designed to infer the worldwide Viral hemorrhagic septicemia virus isolates' genetic diversity and evolutionary dynamics based on G-gene sequences. Methods: The complete G-gene sequences of viral hemorrhagic septicemia virus were retrieved from the public repositories with known timing and geography details. Pairwise statistical analysis was performed using Arlequin. The Bayesian model-based approach implemented in STRUCTURE software was used to investigate the population genetic structure, and the phylogenetic tree was constructed using MEGA X and IQ-TREE. The natural selection analysis was assessed using different statistical approaches, including IFEL, MEME, and SLAC. Results and Discussion: The global Viral hemorrhagic septicemia virus samples are stratified into five genetically distinct subpopulations. The STRUCTURE analysis unveiled spatial clustering of genotype Ia into two distinct clusters at K = 3. However, at K = 5, the genotype Ia samples, deposited from Denmark, showed temporal distribution into two groups. The analyses unveiled that the genotype Ia samples stratified into subpopulations possibly based on spatiotemporal distribution. Several viral hemorrhagic septicemia virus samples are characterized as genetically admixed or recombinant. In addition, differential or subpopulation cluster-specific natural selection signatures were identified across the G-gene codon sites among the viral hemorrhagic septicemia virus isolates. Evidence of low recombination events elucidates that genetic mutations and positive selection events have possibly driven the observed genetic stratification of viral hemorrhagic septicemia virus samples.

4.
BMC Infect Dis ; 22(1): 807, 2022 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-36310166

RESUMO

BACKGROUND: Plasmodium vivax apical membrane antigen-1 (pvama-1) is an important vaccine candidate against Malaria. The genetic composition assessment of pvama-1 from wide-range geography is vital to plan the antigen based vaccine designing against Malaria. METHODS: The blood samples were collected from 84 P. vivax positive malaria patients from different districts of Khyber Pakhtunkhwa (KP) province of Pakistan. The highly polymorphic and immunogenic domain-I (DI) region of pvama-1 was PCR amplified and DNA sequenced. The QC based sequences raw data filtration was done using DNASTAR package. The downstream population genetic analyses were performed using MEGA4, DnaSP, Arlequin v3.5 and Network.5 resources. RESULTS: The analyses unveiled total 57 haplotypes of pvama-1 (DI) in KP samples with majorly prevalent H-14 and H-5 haplotypes. Pairwise comparative population genetics analyses identified limited to moderate genetic distinctions among the samples collected from different districts of KP, Pakistan. In context of worldwide available data, the KP samples depicted major genetic differentiation against the Korean samples with Fst = 0.40915 (P-value = 0.0001), while least distinction was observed against Indian and Iranian samples. The statistically significant negative values of Fu and Li's D* and F* tests indicate the evidence of population expansion and directional positive selection signature. The slow LD decay across the nucleotide distance in KP isolates indicates low nucleotide diversity. In context of reference pvama-1 sequence, the KP samples were identified to have 09 novel non-synonymous single nucleotide polymorphisms (nsSNPs), including several trimorphic and tetramorphic substitutions. Few of these nsSNPs are mapped within the B-cell predicted epitopic motifs of the pvama-1, and possibly modulate the immune response mechanism. CONCLUSION: Low genetic differentiation was observed across the pvama-1 DI among the P. vivax isolates acquired from widespread regions of KP province of Pakistan. The information may implicate in future vaccine designing strategies based on antigenic features of pvama-1.


Assuntos
Malária Vivax , Plasmodium vivax , Humanos , Plasmodium vivax/genética , Irã (Geográfico) , Paquistão/epidemiologia , DNA de Protozoário/genética , Antígenos de Protozoários/genética , Proteínas de Protozoários/genética , Malária Vivax/epidemiologia , Genética Populacional , Variação Genética , Nucleotídeos , Seleção Genética , Análise de Sequência de DNA
5.
Sci Rep ; 12(1): 6171, 2022 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-35418564

RESUMO

Clopidogrel, an antiplatelet drug, is frequently prescribed to patients diagnosed with ischemic diseases such as those suffering from acute coronary syndromes or ischemic stroke. Despite the drug being effective in majority of the patients, some still experience ischemic events early in the treatment which might be due to poor platelet inhibition. This study aims to investigate the association of cytochrome P450 2C19 (CYP2C19) loss-of-function polymorphisms, haplotypes as well as a wide range of clinical and demographic variables with platelet aggregation phenotypes to clopidogrel in a Pakistani cohort. The study comprised of a total of 120 patients diagnosed with cardiovascular diseases and were treated with clopidogrel. Antiplatelet response to clopidogrel was monitored by Helena AggRAM (HL-2-1785P) and patients with maximal platelet aggregation more than 50% were categorized as low responders and those with less than 50% as high responders. Our results show that 56.6% of patients were homozygous for the CYP2C19 wild-type allele, 38.3% of patients possessed one copy of the CYP2C19*2 allele and 5% of patients possessed both CYP2C19*2 alleles. No CYP2C19*3 allele was found in our patient cohort. There was no statistically significant difference between the high and low responder groups to clopidogrel in terms of extensive, intermediate and poor metabolizer genotypes. However, haplotype (H1), leukocyte count, random blood glucose, and history of diabetes mellitus was associated with the antiplatelet response to clopidogrel. The prevalence of clopidogrel resistance in our population was in line with that reported for other regional and global populations.


Assuntos
Inibidores da Agregação Plaquetária , Ticlopidina , Clopidogrel/uso terapêutico , Citocromo P-450 CYP2C19/genética , Genótipo , Haplótipos , Humanos , Isquemia/tratamento farmacológico , Paquistão , Inibidores da Agregação Plaquetária/farmacologia , Inibidores da Agregação Plaquetária/uso terapêutico , Ticlopidina/efeitos adversos , Resultado do Tratamento
6.
Arch Virol ; 167(5): 1235-1245, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35322317

RESUMO

Noroviruses (NoVs), which are members of the family Caliciviridae, are the most common cause of gastroenteritis in humans. Ten NoV genogroups have been reported so far. Of these, genogroup II (GII) is the most prevalent, and it causes serious infections worldwide. The complete genome sequences of NoV GII isolates from different geographical regions were retrieved from the public database. The model-based clustering approach, implemented in the STRUCTURE resource, was employed for assessment of genetic composition. The MEGA X and IQ Tree tools were used for phylogenetic analysis. Genome-wide natural selection analysis was performed using maximum-likelihood-based methods. The demographic features of NoV GII genome sequences were assessed using the BEAST package. All of the NoV GII sequences initially clustered into two main subpopulations at significant K = 2, where the genotype GII.4 samples clearly split from the rest of the genotypes. This indicates a marked genetic distinction between norovirus GII.4 and non-GII.4 samples. Phylogenetic analysis showed the presence of five distinct subclades for genotype GII.2 and seven subclades for GII.4 samples. Several isolates with admixed ancestry were identified that constituted distinct subclusters in the phylogenetic tree. No continental-specific genetic distinctions were observed among the NoV GII samples. Significant genomic signatures of both positive and negative natural selection were identified across the NoV GII genes. A differential pattern of positive selection signals was inferred between the GII.4 and non-GII.4 genotypes. The demographic analysis revealed an increase in the effective population size of NoV GII during 2009-2010, followed by a rapid fall in 2015.


Assuntos
Infecções por Caliciviridae , Norovirus , Genômica , Genótipo , Humanos , Funções Verossimilhança , Filogenia , Seleção Genética
7.
Eur J Hum Genet ; 30(6): 740-746, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35217804

RESUMO

Northern Pakistan is home to many diverse ethnicities and languages. The region acted as a prime corridor for ancient invasions and population migrations between Western Eurasia and South Asia. Kho, one of the major ethnic groups living in this region, resides in the remote and isolated mountainous region in the Chitral Valley of the Hindu Kush Mountain range. They are culturally and linguistically distinct from the rest of the Pakistani population groups and their genetic ancestry is still unknown. In this study, we generated genome-wide genotype data of ~1 M loci (Illumina WeGene array) for 116 unrelated Kho individuals and carried out comprehensive analyses in the context of worldwide extant and ancient anatomically modern human populations across Eurasia. The results inferred that the Kho can trace a large proportion of their ancestry to the population who migrated south from the Southern Siberian steppes during the second millennium BCE ~110 generations ago. An additional wave of gene flow from a population carrying East Asian ancestry was also identified in the Kho that occurred ~60 generations ago and may possibly be linked to the expansion of the Tibetan Empire during 7th to 9th centuries CE (current era) in the northwestern regions of the Indian sub-continent. We identified several candidate regions suggestive of positive selection in the Kho, that included genes mainly involved in pigmentation, immune responses, muscular development, DNA repair, and tumor suppression.


Assuntos
Etnicidade , Genética Populacional , Povo Asiático/genética , Etnicidade/genética , Fluxo Gênico , Humanos , Paquistão
8.
Infect Genet Evol ; 95: 105068, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34492386

RESUMO

Coxsackievirus-A (CV-A) is a causative agent of Hand Foot Mouth Disease (HFMD) worldwide. It belongs to the Human Enterovirus genus of the family Picornaviridae. The genomics data availability of CV-A samples, isolated from human host across different continental regions, provide an excellent opportunity to study its genetic composition, diversity, and evolutionary events. The complete genome sequences of 424 CV-A isolates were analyzed through a model-based population genetic approach implemented in the STRUCTURE program. Twelve genetically distinct sub-populations were identified for CV-A isolates with a marked Fst distinction of 0.76991 (P-value = 0.00000). Besides, genetically admixed strains were characterized in the G-Id, G-IIIb clusters constituted by the CV-A12 and CV-A6 enterovirus serotypes. The serotypes depicted inter/intra-genotype recombination and episodic positive selection signatures in the structural and non-structural protein-coding regions. The observed genetic composition of CV-A samples was also deduced by the phylogenetic tree analyses, where a uniform genetic structure was inferred for most of the CV-A genotypes. However, the CV-A6 serotype samples genetically stratified into three sub-populations that may lead to the emergence of new lineages in future. These informations may implicate in planning the effective strategies to combat the coxsackievirus-A-mediated infection.


Assuntos
Enterovirus Humano C/genética , Genoma Viral , Genótipo , Evolução Molecular , Doença de Mão, Pé e Boca/virologia
9.
PeerJ ; 9: e11149, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34386299

RESUMO

BACKGROUND: Some single nucleotide polymorphisms (SNPs) in the cytochrome P450 (CYP)2B6 gene lead to decreased enzyme activity and have an impact on drug metabolism. The present study was designed to investigate the patterns of genetic distinction across a hypervariable region of the CYP2B6 gene, known to contain important SNPs, i.e. rs4803419 and rs3745274, among five major ethnic groups of the Pakistani population. METHODS: Arlequin v3.5.DnaSPv6.12. and network 5 resources were used to analyze population genetic variance in the partial CYP2B6 gene sequences obtained from 104 human samples belonging to Punjabi, Pathan, Sindhi, Seraiki and Baloch ethnicities of Pakistan. The partial CYP2B6 gene region analyzed in the current study is previously known to possess important SNPs. RESULTS: The data analyses revealed that genetic variance among samples mainly came from differentiation within the ethnic groups. However, significant genetic variation was also found among the various ethnic groups. The high pairwise Fst genetic distinction was observed between Seraiki and Sindhi ethnic groups (Fst = 0.13392, P-value = 0.026) as well as between Seraiki and Balochi groups (Fst = 0.04303, P-value = -0.0030). However, the degree of genetic distinction was low between Pathan and Punjabi ethnic groups. Some SNPs, including rs3745274 and rs4803419, which are previously shown in strong association with increased plasma Efavirenz level, were found in high frequency. Besides, a novel SNP, which was not found in dbSNP and Ensemble databases, was identified in the Balochi ethnicity. This novel SNP is predicted to affect the CYP2B6 splicing pattern. CONCLUSION: These results may have significant implications in Pakistani ethnicities in the context of drugs metabolized by CYP2B6, especially in Seraiki and Balochi ethnicity. The novel heterogeneous SNP, found in the present study, might lead to altered drug-metabolizing potential of CYP2B6 and, therefore, may be implicated in non-responder phenomenon.

10.
Water Sci Technol ; 84(3): 609-631, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34388122

RESUMO

Serious environmental deterioration caused by synthetic waste plastics, and the pollution of freshwater resources are the most alarming and marked challenges of the 21st century. Therefore, immense scientific efforts are being made towards the management of waste plastics and treatment of polluted water. The current study reports on the utilization of waste polyethylene terephthalate (wPET) and waste polystyrene (wPS) for fabrication of activated carbon (AC) and its application for the removal of hazardous polycyclic aromatic hydrocarbons (PAHs) pollutants from water. AC was prepared from wPET and wPS by carbonization under a N2 atmosphere followed by chemical activation with 1 M KOH and 1 M HCl. The AC was characterized by scanning electron microscopy, surface area analysis, and Fourier transform infrared spectroscopy. Adsorption of PAHs from aqueous solutions through AC was examined by batch adsorption tests. The optimum parameters for maximum adsorption of PAHs were found to be: initial PAHs concentration 40 ppm, 2 h contact time, pH 3, 5, and 7, 50 °C temperature and adsorbent dose of 0.8 g. Kinetic and isotherm models were applied to evaluate the adsorbent capacity for PAHs adsorption. The kinetic study shows that the adsorption of these PAHs onto AC follows pseudo-second-order kinetics. The experimental results demonstrated that the Langmuir isotherm model best fitted the data. The thermodynamic factors calculated such as entropy change (ΔS°), enthalpy change (ΔS°) and free energy change (ΔG°) show that the adsorption process is non-spontaneous and endothermic in nature. Results were also compared with the efficiencies of some commercial adsorbents used in practice. This examination revealed that the novel plastic-derived AC possesses a great potential for elimination and recovery of PAH elimination from industrial wastewater.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos , Poluentes Químicos da Água , Adsorção , Carvão Vegetal , Descontaminação , Concentração de Íons de Hidrogênio , Cinética , Plásticos , Espectroscopia de Infravermelho com Transformada de Fourier , Termodinâmica , Águas Residuárias , Poluentes Químicos da Água/análise
11.
Environ Geochem Health ; 43(9): 3615-3624, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33606135

RESUMO

This study aimed to determine the status of groundwater contamination with faecal coliform and nitrate in the rural areas of Mardan district, Pakistan. Both analytes require regular monitoring according to the National Environmental Quality Standards (NEQS) of Pakistan. Groundwater samples (n = 100) were collected from 25 villages across four zones. Samples were analysed for physicochemical parameters including pH, electrical conductivity (EC), Escherichia coli (E. coli) contamination, nitrite, and nitrate ([Formula: see text] and [Formula: see text]). Whilst the average concentrations of [Formula: see text] in the water samples were within the permissible limits of 50 mg L-1 set by the World Health Organisation (WHO) and NEQS two villages exceeded the safety limits. Non-carcinogenic health risks of [Formula: see text] were estimated in terms of average daily dose (ADD) and hazard quotient (HQ). The HQ values for [Formula: see text] were > 1 for children signifying potential health risks; however, the adult population had HQ < 1 which indicates no risk. Groundwater samples tested positive for E. coli contamination in 13 villages, suggesting that residents may be living at risk of various microbial diseases due to drinking of contaminated water. The findings of this study provide valuable baseline data for groundwater researchers, policymakers, and the local public health department.


Assuntos
Água Potável , Água Subterrânea , Poluentes Químicos da Água , Adulto , Criança , Água Potável/análise , Monitoramento Ambiental , Escherichia coli , Humanos , Nitratos/análise , Paquistão , Medição de Risco , Poluentes Químicos da Água/análise
12.
Front Immunol ; 10: 581, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30972073

RESUMO

Triterpenes possess anti-inflammatory and anti-nociceptive effects. In this study anti-inflammatory activities of Asparacosin A were evaluated' using in-vitro cyclooxygenases 1 and 2 (COX-1/2) inhibition assays. Moreover, anti-nociceptive activities were assessed in-vivo by carrageenan-induced paw edema test, xylene-induced ear edema tests, and acetic acid-induced writhing and formalin tests. Additionally molecular docking was conducted to elucidate the binding mechanism of the compound and to correlate the in-vitro findings with the in-silico data. Oral administration of Asparacosin A at the doses of 10, 20, and 40 mg/kg induced significant anti-inflammatory effects (*p < 0.05, **p < 0.01, and ***p < 0.001) in a dose-dependent manner in both models. Asparacosin A also inhibited the human recombinant COX-2 enzyme and caused a dose-dependent decrease in the levels of TNF-α, IL-1ß, and PGE2 in the carrageenan-induced paws. Moreover, Asparacosin A displayed significant anti-nociceptive effects (*p < 0.05, **p < 0.01, ***p < 0.001) at the doses of 10, 20, and 40 mg/kg in acetic-acid induced writhing test. However, in formalin test, Asparacosin A (10-40 mg/kg, p.o) produced anti-nociceptive effects only in the late phase, similar to the effect observed with the reference drug celecoxib (50 mg/kg, p.o). Molecular docking was carried out on both COX-1 and COX-2 structures which revealed that Asparacosin A targets allosteric binding site similar to the binding mode of the selective COX inhibitor. In conclusion, Asparacosin A exhibits anti-inflammatory and peripheral anti-nociceptive activities which are likely mediated via inhibition of COX-2 enzyme and inflammatory cytokines. Furthermore, Asparacosin A can serve as a model to obtain new and more selective potent anti-inflammatory and anti-nociceptive drugs.


Assuntos
Analgésicos/farmacologia , Anti-Inflamatórios/farmacologia , Inibidores de Ciclo-Oxigenase 2/farmacologia , Citocinas/antagonistas & inibidores , Espirostanos/farmacologia , Animais , Ciclo-Oxigenase 2/química , Camundongos , Simulação de Acoplamento Molecular , Ratos , Ratos Sprague-Dawley , Espirostanos/toxicidade
13.
Rev Environ Health ; 34(2): 171-186, 2019 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-30990788

RESUMO

In developing countries, one of the most severe modern-day dilemmas is the management of industrial wastewater. In these countries, industrial wastewater effluents are directly discharged into the natural drain, a sewer system, an internal septic tank or a nearby field. Some of these industrial wastewater effluents are inadequately treated or untreated before being discharged. In recent years, in developing countries, urbanization and industrial activities have led to environmental deterioration. This paper was designed to review the health and environmental impacts of inadequately treated or untreated industrial wastewater effluents in Pakistan. The quality of industrial wastewater effluents is responsible for the degradation of the receiving water bodies. This is due to the reason that inadequately treated or untreated industrial wastewater effluents may cause eutrophication in the receiving water bodies and also form a favorable condition for toxin-producing waterborne pathogens. In order to comply with the wastewater guidelines and legislations, there is a need for proper treatment before discharge. In order to minimize the risk to the environment and public health, there is a need for proper treatment processes for industrial wastewater effluents. To achieve unpolluted discharge of industrial wastewater into the receiving water bodies, regular monitoring, proper and suitable treatment, careful planning and appropriate legislation are recommended.


Assuntos
Saúde Ambiental , Monitoramento Ambiental , Resíduos Industriais/efeitos adversos , Águas Residuárias/análise , Poluentes Químicos da Água/efeitos adversos , Saúde Ambiental/economia , Saúde Ambiental/legislação & jurisprudência , Saúde Ambiental/estatística & dados numéricos , Eutrofização , Humanos , Resíduos Industriais/análise , Paquistão , Eliminação de Resíduos Líquidos , Águas Residuárias/legislação & jurisprudência , Poluentes Químicos da Água/análise
14.
Environ Monit Assess ; 190(11): 649, 2018 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-30338404

RESUMO

From health and environmental point of views, dioxins are important due to their toxicity and persistence. Dioxins have the potential to reside in the environment for longer time if sorbed onto the clay and organic content of the soil matrix. Their transport or leaching under certain environmental conditions such as preferential flow can increase the risk of groundwater contamination. In the current study, breakthrough curves (BTCs) against time were plotted for selected dioxin transport prediction; based on measured distribution coefficient (Kd), dispersion coefficient (D), and retardation factor (R). Three representative soil series named Burhan, Warsak, and Kunda were selected. For dibenzo-p-dioxin (DD), Kd values followed the order as: Burhan> Warsak > Kunda, while for 2-chloro dibenzo-p-dioxin (2 Cl-DD), Kd values followed an order as: Kunda > Burhan > Warsak. Dioxin transport was measured at two different linear velocities (20 and 50 cm day-1). Attainment of equilibrium was verified to be dependent upon the Kd, R, D, and chlorination on dioxin. Kunda series with low OM (0.6%), clay (0.2%), and R (377) was found to have relatively high DD transport potential under normal velocity, due to high dispersion values for its sandy nature. Under the steady or preferential flow conditions, all the plots obtained were identical irrespective of soil type and dioxin nature.


Assuntos
Dioxinas/análise , Monitoramento Ambiental , Poluentes do Solo/análise , Solo/química , Adsorção , Silicatos de Alumínio , Argila , Dibenzodioxinas Policloradas , Medição de Risco
15.
J Environ Sci (China) ; 72: 1-12, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30244736

RESUMO

Fecal bacteria contaminate water resources and result in associated waterborne diseases. This study assessed drinking water quality and evaluated their potential health risks in Swat, Pakistan. Ground and surface drinking water were randomly collected from upstream to downstream in the River Swat watershed and analyzed for fecal contamination using fecal indicator bacteria (Escherichia coli) and physiochemical parameters (potential of hydrogen, turbidity, temperature, electrical conductivity, total dissolved solid, color, odor and taste). The physiochemical parameters were within their safe limits except in a few locations, whereas, the fecal contaminations in drinking water resources exceeded the drinking water quality standards of Pakistan Environmental Protection Agency (Pak-EPA), 2008 and World Health Organization (WHO), 2011. Multivariate and univariate analyses revealed that downstream urbanization trend, minimum distance between water sources and pit latrines/sewerage systems, raw sewage deep well injection and amplified urban, pastures and agricultural runoffs having human and animal excreta were the possible sources of contamination. The questionnaire survey revealed that majority of the local people using 10-20years old drinking water supply schemes at the rate of 73% well supply, 13% hand pump supply, 11% spring supply and 3% river/streams supply, which spreads high prevalence of water borne diseases including hepatitis, intestinal infections and diarrhea, dysentery, cholera, typhoid fever, jaundice and skin diseases in children followed by older and younger adults.


Assuntos
Água Potável/microbiologia , Exposição Ambiental/estatística & dados numéricos , Abastecimento de Água/estatística & dados numéricos , Água Potável/química , Fezes/microbiologia , Humanos , Paquistão , Microbiologia da Água
16.
Rev Environ Health ; 33(4): 383-406, 2018 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-30205648

RESUMO

Context Materials which exceed the balance of their production and destruction lead to the deterioration in the environment. Plastic is one such material which poses a big threat to the environment. A huge amount of plastic is produced and dumped into the environment which does not readily degrade naturally. In this paper, we address the organization of a large body of literature published on the management of waste plastics being the most challenging issue of the modern world. Objectives To address the issue of the management of waste plastics, there is a dire need to organize the literature published in this field. This paper presents a systematic literature review on plastic waste, its fate and biodegradation in the environment. The objective is to make conclusions on possible practical techniques to lessen the effects of plastic waste on the environment. Method A systematic literature review protocol was followed for conducting the present study [Kitchenham B, Brereton OP, Budgen D, Turner M, Bailey J, Linkman S. Systematic literature reviews in software engineering - A systematic literature review. Inf Softw Technol 2009;51(1):7-15.]. A predefined set of book sections, conference proceedings and high-quality journal publications during the years 1999 to September 2017 were used for data collection. Results One hundred and fifty-three primary studies are selected, based on predefined exclusion, inclusion and quality criteria. These studies will help to identify the fate of different waste plastics, their impact and management and the disposal techniques frequently used. The study also identifies a number of significant techniques and measures for the conversion of waste plastic materials into useful products. Conclusion Five fundamental strategies are used for the handling of plastic waste. These strategies include: recycling, depositing in landfill, incineration, microbial degradation and conversion into useful materials. All of these methods have their own limitations, due to which there is need to explore the studies for optimum solutions of the management of plastics waste.


Assuntos
Poluentes Ambientais/efeitos adversos , Plásticos/efeitos adversos , Gerenciamento de Resíduos/métodos , Biodegradação Ambiental
17.
J Photochem Photobiol B ; 158: 174-83, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26974578

RESUMO

A series of organotin(IV) carboxylate complexes: [Me2SnL2] (1), [n-Bu2SnL2] (2), [n-Oct2SnL2] (3), [Me3SnL] (4), [n-Bu3SnL] (5) and [Ph3SnL] (6), where L=3-(4-fluorophenyl)acrylic acid, have been successfully synthesized and characterized by FT-IR, NMR ((1)H, (13)C) and single crystal analysis. The ligand coordinates to tin atom via carboxylate group. Compound 4 was also analyzed by single crystal XRD analysis. Crystallographic data for trimethyltin(IV) complex showed that the tin has approximate trigonal bipyramidal geometry with the CH3 groups in the trigonal plane. The carboxylate groups bridge the adjacent tin atoms, resulting in polymeric chains. FT-IR and NMR data also support the 5-coordination geometry for the triorganotin(IV) derivatives. In the case of the diorganotin(IV) derivatives a six-coordinate geometry at the tin atom is proposed from spectroscopic data. The Me-Sn-Me bond angle in complexes 1 and 4 was determined from the (2)J[(119)Sn-(1)H] value as 138.4° and 111° that falls in the range of 5-coordinated trigonal bipyramidal and 6-coordinated octahedral geometries, respectively. The synthesized compounds were screened for their biological activities including antibacterial, antifungal and cytotoxicity. The compounds 4-6 exhibit excellent antibacterial, antifungal and cytotoxic activities. The cytotoxicity data reveals that the HL and 1-3 are almost non-toxic and exhibited LD50 values in the range 73.45-675.1µg/mL while 4-6 are found to be cytotoxic to mildly cytotoxic with LD50 values in the range 6.43-13.49µg/mL. The compound interacts with DNA via intercalation of aromatic ring into the base pairs of DNA resulting in hypochromism and minor red shift.


Assuntos
Ácidos Carboxílicos/química , Compostos Orgânicos de Estanho/farmacologia , Antibacterianos/química , Antibacterianos/farmacologia , Antifúngicos/química , Antifúngicos/farmacologia , Linhagem Celular Tumoral , Cristalografia por Raios X , Humanos , Espectroscopia de Ressonância Magnética , Compostos Orgânicos de Estanho/química , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier
18.
ScientificWorldJournal ; 2015: 562693, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25705714

RESUMO

The ash of C. polygonoides (locally called balanza) was collected from Lakki Marwat, Khyber Pakhtunkhwa, Pakistan, and was utilized as biosorbent for methylene blue (MB) removal from aqueous solution. The ash was used as biosorbent without any physical or chemical treatment. The biosorbent was characterized by using various techniques such as Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), and scanning electron microscopy (SEM). The particle size and surface area were measured using particle size analyzer and Brunauer-Emmett-Teller equation (BET), respectively. The SEM and BET results expressed that the adsorbent has porous nature. Effects of various conditions such as initial concentration of methylene blue (MB), initial pH, contact time, dosage of biosorbent, and stirring rate were also investigated for the adsorption process. The rate of the adsorption of MB on biomass sample was fast, and equilibrium has been achieved within 1 hour. The kinetics of MB adsorption on biosorbent was studied by pseudo-first- and pseudo-second-order kinetic models and the pseudo-second-order has better mathematical fit with correlation coefficient value (R (2)) of 0.999. The study revealed that C. polygonoides ash proved to be an effective, alternative, inexpensive, and environmentally benign biosorbent for MB removal from aqueous solution.


Assuntos
Azul de Metileno/isolamento & purificação , Polygonaceae/química , Poluentes Químicos da Água/isolamento & purificação , Purificação da Água/métodos , Absorção Fisico-Química , Cinética , Azul de Metileno/química , Azul de Metileno/metabolismo , Microscopia Eletrônica de Varredura , Tamanho da Partícula , Espectroscopia de Infravermelho com Transformada de Fourier , Termogravimetria , Poluentes Químicos da Água/química , Poluentes Químicos da Água/metabolismo
19.
Pest Manag Sci ; 71(12): 1640-8, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25580715

RESUMO

BACKGROUND: Growing demand for reduced chemical inputs in agricultural systems requires more effective integration of biological control with pesticides. The egg parasitoid Trichogramma pretiosum Riley is an important natural enemy of lepidopteran pests, used in biological control. In an investigation of the interaction of T. pretiosum and pesticides, we studied the acute toxicity of 19 pesticides (insecticides, miticides, fungicides and herbicides) to adult parasitoids and the behavioral effects of 11 pesticides on foraging parasitoid females, including host antennation, stinging and host feeding. RESULTS: At recommended field doses, fipronil, dinotefuran, spinetoram, tolfenpyrad and abamectin induced nearly 100% adult mortality within 24 h of exposure to treated cotton leaves by comparison with controls. Acetamiprid was also toxic, but significantly less so than the former materials. The other pesticides had no significant toxic effects. Only glufosinate ammonium exhibited increased toxicity among the non-toxic materials when increased two- or fourfold over recommended rates. The foraging behavior of parasitoids was affected only by tolfenpyrad among the materials tested. CONCLUSION: Most novel pesticides, except for several insecticides, exhibited little to no acute toxicity to the parasitoid. Parasitoid foraging behavior was only affected by tolfenpyrad, indicating that parasitoids could successfully forage on eggs treated with most pesticides evaluated. Therefore, many of these pesticides may have good compatibility with Trichogramma.


Assuntos
Comportamento Apetitivo/efeitos dos fármacos , Controle Biológico de Vetores , Praguicidas/toxicidade , Vespas/efeitos dos fármacos , Animais , Comportamento Alimentar/efeitos dos fármacos , Feminino , Gossypium , Mordeduras e Picadas de Insetos , Mariposas/parasitologia , Óvulo/parasitologia , Resíduos de Praguicidas/toxicidade , Vespas/crescimento & desenvolvimento
20.
Bioinorg Chem Appl ; 2014: 916361, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25276113

RESUMO

Five heteroleptic palladium(II) complexes of the general formula Pd(PR3)(tu)Cl2, where PR3 = triphenylphosphine (1), diphenyl-o-tolylphosphine (2), diphenyl-p-tolylphosphine (3), diphenyl-t-butylphosphine (4), and diphenyl-o-methoxyphenylphosphine (5), and tu = 1,3-bis(2-methoxyphenyl) thiourea. They all have been synthesized and characterized by various spectroscopic techniques (elemental analysis, FTIR, and (1)H NMR and the ligand 1,3-bis(2-methoxyphenyl) thiourea was synthesized by single crystal X-ray diffraction technique). The synthesized compounds were screened for their antibacterial activity against four strains of bacteria (Escherichia coli, Shigella flexneri, Staphylococcus aureus, and Bacillus subtilis). The antitumor potential was evaluated in terms of activity against brine shrimp eggs and DNA interaction. The mixed ligand complexes have exhibited moderate antibacterial activity and promising antitumor potential.

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