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41.
Almas  Fakhrah  Hassan  Adeel  Bibi  Arfa  Ali  Masab  Lateef  Sadia  Mahmood  Tariq  Rasheed  Awais  Quraishi  Umar Masood 《Plant and Soil》2018,431(1-2):371-387
Plant and Soil - Extreme climate events, including flooding and prolonged drought, may establish long-lasting (legacy) effects on soil abiotic and biotic properties, potentially influencing soil...  相似文献   
42.
Abstract

Hexachlorocyclohexane (HCH), a highly chlorinated pesticide, was used worldwide in the 1950s and 1960s. HCH toxic residues are still detected in environmental compartments. Thus, effective, viable and eco-friendly strategy is required for its remediation. In this study, degradation of four HCH isomers was evaluated by amending contaminated soil using four treatments of spent mushroom compost (SMC) of Pleurotus ostraetus. The soil was incubated for 5 weeks and was sampled every seven days. Quantitative attenuation in HCH was calculated using gas chromatography–electron capture detector (GC-ECD) and metabolite was identified using gas chromatography–mass selective detector (GC-MSD). Maximum reduction 58%, 26%, 45%, and 64% for α-, β-, γ- and δ-HCH isomers, respectively, using SMC and soil (both unsterilized) showed that this treatment was the best for bioremediation of HCH in soil. However, when one of the factors, either soil or SMC, was sterilized, a significant reduction in HCH degradation was noticed. The second most reduction of isomers was seen during treatment where unsterilized SMC was added in sterilized soil followed by treatment where SMC was sterilized but soil was not. Abiotic control did not remove any significant quantities of HCH. Simple first-order (SFO) kinetic confirmed that SMC reduced the half-live manifolds as compared to biotic control. Only one metabolite δ-PCCH was identified during the course of study.  相似文献   
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Middle East Respiratory Syndrome Coronavirus (MERS-CoV) is a zoonotic pathogen capable of causing severe respiratory disease in humans. Although dromedary camels are considered as a major reservoir host, the MERS-CoV infection dynamics in camels are not fully understood. Through surveillance in Pakistan, nasal (n = 776) and serum (n = 1050)samples were collected from camels between November 2015 and February 2018. Samples were collected from animal markets, free-roaming herds and abattoirs. An in-house ELISA was developed to detect IgG against MERS-CoV. A total of 794 camels were found seropositive for MERS-CoV. Prevalence increased with the age and the highest seroprevalence was recorded in camels aged [ 10 years (81.37%) followed by those aged 3.1–10 years (78.65%) and B 3 years (58.19%).Higher prevalence was observed in female (78.13%) as compared to male (70.70%). Of the camel nasal swabs, 22 were found to be positive by RT-qPCR though with high Ct values. Moreover, 2,409 human serum samples were also collected from four provinces of Pakistan during 2016–2017. Among the sampled population, 840 humans were camel herders.Although we found a high rate of MERS-CoV antibody positive dromedaries (75.62%) in Pakistan, no neutralizing antibodies were detected in humans with and without contact to camels.  相似文献   
44.
BACKGROUND: Androgen receptor (AR) has emerged as a significant prognostic marker in early breast cancer (BCa). Association of AR with cancer stem cell (CSC) markers in BCa is unknown. Aim of the present study was to evaluate the immunohistochemical expression of AR, CD44, CD24 and ALDH1 in a cohort of Pakistani patients diagnosed with invasive BCa and to correlate the expression with 5- year disease free survival. PATIENTS AND METHODS: We evaluated immunohistochemical expression AR, CD44, CD24 and ALDH1 in formalin fixed paraffin embedded archival blocks of 166 cases of primary invasive BCa (stage I-III) and correlated the expression with clinicopathological variables and outcome using univariable and multivariable analysis. Survival data was computed by Kaplan Meier curves. RESULTS: Expression of AR was observed in 62.7% tumors whereas CD44, CD24 and ALDH1 were expressed in 61.4%, 44% and 30.1% tumors, respectively. AR expression was significantly associated with T1-T2 tumors, lower grade, estrogen and progesterone receptor expression (P < .05) and remained an independent prognostic indicator in multivariable analysis (adjusted HR 0.33, 95% CI 0.13–0.81; P = .016). Significant association was observed between concordant expression of AR and CD24 (P = .001) with a favorable impact on survival (P = .007) whereas expression of CSC phenotypes (CD44+, CD44+/CD24? and ALDH1+) did not correlate with adverse outcome (P > .05). However, AR expression retained the association with better prognosis even in patients whose tumors exhibited a CSC phenotype. CONCLUSIONS: Expression of AR and CD24 in stage I-III invasive BCa correlates with favorable clinicopathological features and delineates a subgroup of patients with better disease-free survival.  相似文献   
45.
This study assessed the protective effects of Cinnamomum cassia (cinnamon) bark extract in rats exposed to titanium dioxide nanoparticles or titanium dioxide bulk salt. For in vivo evaluation of the ameliorative role of the cinnamon extract, the experimental groups were orally administered with the cinnamon extract at different dose levels (50 or 100 or 150 mg/kg bodyweight) along with the subcutaneous injections of 150 mg/kg bodyweight titanium dioxide nanoparticles or titanium dioxide bulk salt. The extract showed significant ameliorative role on the antioxidant system in response to elevated levels of titanium dioxide nanoparticles or titanium dioxide bulk salt-induced oxidative stress. It aided in the recovery of the antioxidant system as well as protective role in histological damages and some haematological parameters in the rat liver treated with titanium dioxide nanoparticles or titanium dioxide bulk salt.  相似文献   
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BACKGROUND: In a population‐based case‐control study, we investigated the association between congenital cardiovascular malformations (CVMs) and maternal urinary tract infections (UTIs). METHODS: Within the National Birth Defects Prevention Study, 3,690 women who had singleton livebirths with nonsyndromic CVMs, and 4,760 women who had infants without birth defects were identified. Affected infants had: conotruncal, septal, anomalous pulmonary venous return, atrioventricular septal defects, or left‐ or right‐sided obstructive heart defects. Mothers had a UTI if they reported having at least one infection during the first trimester. Adjusted ORs and 95% CIs were computed to determine the association between CVMs and UTIs. Stratified analyses were conducted to investigate if sulfonamide use and/or fever modified the effect between CVMs and UTIs. RESULTS: Women who had offspring with either left ventricular outflow tract obstructive defects or atrioventricular septal defects were more likely than controls to report a UTI. These associations remained among women who did not have fever or used sulfonamides. Maternal use of sulfonamides during the UTI did not appear to modify the relationship between CVM subtypes and maternal UTIs. CONCLUSIONS: In the National Birth Defects Prevention Study there was little evidence to support an association between CVMs and UTIs during the first trimester of pregnancy. Associations between left ventricular outflow tract obstructive defects and maternal UTI as well as between atrioventricular septal defects and maternal UTI were found. Our findings, while not conclusive, suggest that the possible association between maternal UTI and CVMs should be investigated further. Birth Defects Research (Part A), 2008. © 2008 Wiley‐Liss, Inc.  相似文献   
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It has been speculated that trace elements may a play role in the pathogenesis of heart diseases. In the present study, we aimed to assess the levels of selenium (Se) and mercury (Hg) in biological samples (whole blood, urine, and scalp hair) of myocardial infarction (MI) patients of both genders (age range 45–60 years) at the first, second, and third heart attack (n?=?130), hospitalized in a cardiac ward of a civil hospital of Hyderabad City (Pakistan). For comparison, healthy age-matched referent subjects (n?=?61) of both genders were also selected. Se and Hg in biological samples were measured by electrothermal atomic absorption spectrometry and cold vapor atomic absorption spectrometry, prior to microwave acid digestion, respectively. The validity of the methodology was checked by biological certified reference materials. During this study, 78 % of the 32 registered patients of third MI attack (aged >50 years) died. The concentration of Se was decreased in scalp hair and blood samples of MI patients, while Hg was higher in all biological samples as compared to referent subjects. Se concentration was inversely associated with the risk of MI attacks in both genders. These results add to an increasing body of evidence that Se is a protective element for cardiovascular health.  相似文献   
50.
Microsatellites or simple sequence repeats (SSRs) were used for the estimation of genetic diversity among a group of 40 sunflower lines developed at the research area of Department of Plant Breeding and Genetics, University of Agriculture, Faisalabad. Total numbers of alleles amplified by 22 polymorphic primers were 135 with an average of 6.13 alleles per locus, suggesting that SSR is a powerful technique for assessment of genetic diversity at molecular level. The expected heterozygosity (PIC) ranged from 0.17 to 0.89. The highest PIC value was observed at the locus C1779. The genetic distances ranged from 9% to 37%. The highest genetic distance was observed between the lines L50 and V3. Genetic distances were low showing lesser amount of genetic diversity among the sunflower lines.  相似文献   
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