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151.
Shakirullah?Khan?Shakir Memoona?Kanwal Waheed?Murad Zia ur Rehman Shafiq ur Rehman M.?K.?Daud Azizullah?AzizullahEmail author 《Ecotoxicology (London, England)》2016,25(2):329-341
Pesticides are highly toxic substances. Their toxicity may not be absolutely specific to the target organisms but can adversely affect different processes in the non-target host plants. In the present study, the effect of over application of four commonly used pesticides (emamectin benzoate, alpha-cypermethrin, lambda-cyhalothrin and imidacloprid) was evaluated on the germination, seedling vigor and photosynthetic pigments in tomato. The obtained results revealed that seed germination was decreased by the pesticides and this effect was more prominent at early stages of exposure. All the tested pesticides reduced the growth of tomato when applied in higher concentration than the recommended dose, but at lower doses the pesticides had some stimulatory effects on growth as compared to the control. A similar effect of pesticides was observed on the photosynthetic pigments, i.e. a decrease in pigments concentrations was caused at higher doses but an increase was observed at lower doses of pesticides. The calculation of EC50 values for different parameters revealed the lowest EC50 values for emamectin (ranged as 51–181 mg/L) followed by alpha-cypermethrin (191.74–374.39), lambda-cyhalothrin (102.43–354.28) and imidacloprid (430.29–1979.66 mg/L). A comparison of the obtained EC50 values for different parameters of tomato with the recommended doses revealed that over application of these pesticides can be harmful to tomato crop. In a few cases these pesticides were found toxic even at the recommended doses. However, a field based study in this regard should be conducted to further verify these results. 相似文献
152.
A Zamauskaite I Perez-Cruz M M Yaqoob J A Madrigal S B Cohen 《Nephrology, dialysis, transplantation》1999,14(1):49-55
INTRODUCTION: Dialysis has been associated with acute changes in the complement activation status, granulocyte markers, macrophage function, T cell activation and the release of pro-inflammatory cytokines. The most common analysis of cytokine production in patients on dialysis has focused on the changes in monokines (particularly IL-1 and TNF alpha), however it is becoming clear that T cell cytokines play a major role in the impaired lymphocyte function of dialysis patients. METHODS: To assess the effect of dialysis modality on T cell function we analysed the ability of T cells within peripheral blood mononuclear cell populations (PBMC) to produce cytokines after mitogen (phorbol-12-myristate-13-acetate; PMA and lonomycin; I) stimulation in patients on peritoneal dialysis (PD) compared to low flux haemodialysis (HD) and normal individuals (controls). RESULTS: In control PBMC, PMA + I stimulation significantly increased the percentage of CD3+ cells expressing IL-2, IFN gamma, TNF alpha, IL-4 and IL-10, as expected. However, although mitogen stimulation significantly enhanced the percentage of the classical Th1 cytokines (IL-2, IFN gamma and TNF alpha) in the low flux HD PBMC, it had no effect on CD3+ IL-2 or CD3+ TNF alpha producing cells in the PD group. In contrast, the percentage of T cells producing Th2 cytokines (IL-4 and IL-10) could not be consistently enhanced by mitogen in either dialysis group. CONCLUSIONS: We suggest that PD alters the ability of T cells to produce cytokines, possibly by causing an 'exhaustion' of the Th1 cells, thereby preventing cells to produce cytokine on ex vivo stimulation. Furthermore, since T cells from both low flux HD and PD groups could not be induced to produce Th2 cytokines we suggest that uraemia or dialysis per se inhibits T cells from producing Th2 cytokines. 相似文献
153.
Tahira Yaqoob Malika Rani Arshad Mahmood Rubia Shafique Safia Khan Naveed Kausar Janjua Aqeel Ahmad Shah Awais Ahmad Abdullah A. Al-Kahtani 《Materials》2021,14(20)
MXene/Ag2CrO4 nanocomposite was synthesized effectively by means of superficial low-cost co-precipitation technique in order to inspect its capacitive storage potential for supercapacitors. MXene was etched from MAX powder and Ag2CrO4 spinel was synthesized by an easy sol-gel scheme. X-Ray diffraction (XRD) revealed an addition in inter-planar spacing from 4.7 Å to 6.2 Å while Ag2CrO4 nanoparticles diffused in form of clusters over MXene layers that had been explored by scanning electron microscopy (SEM). Energy dispersive X-Ray (EDX) demonstrated the elemental analysis. Raman spectroscopy opens the gap between bonding structure of as-synthesized nanocomposite. From photoluminence (PL) spectra the energy band gap value 3.86 eV was estimated. Electrode properties were characterized by applying electrochemical observations such as cyclic voltammetry along with electrochemical impedance spectroscopy (EIS) for understanding redox mechanism and electron transfer rate constant Kapp. Additionally, this novel work will be an assessment to analyze the capacitive behavior of electrode in different electrolytes such as in acidic of 0.1 M H2SO4 has specific capacitance Csp = 525 F/g at 10 mVs−1 and much low value in basic of 1 M KOH electrolyte. This paper reflects the novel synthesis and applications of MXene/Ag2CrO4 nanocomposite electrode fabrication in energy storage devices such as supercapacitors. 相似文献
154.
Seyed Zia Razavinasab Iraj Sharifi Mohammad Reza Aflatoonian Zahra Babaei Mohammad Ali Mohammadi Ehsan Salarkia Fatemeh Sharifi Abbas Aghaei Afshar Mehdi Bamorovat 《Transboundary and Emerging Diseases》2019,66(4):1602-1610
Cutaneous leishmaniasis (CL) has increased remarkably in Iran and has expanded into new areas. The present study aimed to assess the emerging CL outbreak in southeastern Iran using high resolution melting‐polymerase chain reaction (HRM‐PCR) and phylogenetic analysis using the 7SL RNA gene marker. A cross‐sectional and analytical survey was conducted during a house‐to‐house census of 11,021 inhabitants in Narmashir County in southeastern Iran in 2016. The cases were detected by direct smear microscopic examination and sequencing and were characterized using the 7SL RNA gene. All age groups and sexes were equally affected. Most were single lesions (70.7%). The hands (55.2%) and face (37.9%) were the main sites of involvement. The disease was more common among illiterate persons. Sequencing and HRM‐PCR revealed that Leishmania tropica (accession no. MH632168 Qale‐Shahid) was the principal causative agent of anthroponotic CL (ACL) in new areas of expansion. This is the first emergence of ACL in rural areas of Narmashir County. Based on the molecular data, the causative parasite species confirmed to be L. tropica. Sequencing and phylogenetic analysis indicated that a single clone of the organism derived from a single source has spread into the affected villages. Construction of a main road, population movement and recent urbanization in the area are likely the major factors associated with the establishment of this new outbreak. This study was essential to enable the planning of effective therapeutic and prophylactic measures to control the disease. 相似文献
155.
Many observers have noted that the morphological changes that occur in chronic kidney disease(CKD) patients resemble those seen in the geriatric population, with strikingly similar morbidity and mortality profiles and rates of frailty in the two groups, and shared characteristics at a pathophysiological level especially in respect to the changes seen in their vascular andimmune systems. However, whilst much has been documented about the shared physical characteristics of aging and uremia, the molecular and cellular similarities between the two have received less attention. In order to bridge this perceived gap we have reviewed published research concerning the common molecular processes seen in aging subjects and CKD patients, with specific attention to altered proteostasis, mitochondrial dysfunction, post-translational protein modification, and senescence and telomere attrition. We have also sought to illustrate how the cell death and survival pathways apoptosis, necroptosis and autophagy are closely interrelated, and how an understanding of these overlapping pathways is helpful in order to appreciate the shared molecular basis behind the pathophysiology of aging and uremia. This analysis revealed many common molecular characteristics and showed similar patterns of cellular dysfunction. We conclude that the accelerated aging seen in patients with CKD is underpinned at the molecular level, and that a greater understanding of these molecular processes might eventually lead to new much needed therapeutic strategies of benefit to patients with renal disease. 相似文献
156.
Johanna Berg Zia Weber Mona Fechler-Bitteti Andreas C. Hocke Stefan Hippenstiel Laura Elomaa Marie Weinhart Jens Kurreck 《Viruses》2021,13(8)
Influenza A virus (IAV) continuously causes epidemics and claims numerous lives every year. The available treatment options are insufficient and the limited pertinence of animal models for human IAV infections is hampering the development of new therapeutics. Bioprinted tissue models support studying pathogenic mechanisms and pathogen-host interactions in a human micro tissue environment. Here, we describe a human lung model, which consisted of a bioprinted base of primary human lung fibroblasts together with monocytic THP-1 cells, on top of which alveolar epithelial A549 cells were printed. Cells were embedded in a hydrogel consisting of alginate, gelatin and collagen. These constructs were kept in long-term culture for 35 days and their viability, expression of specific cell markers and general rheological parameters were analyzed. When the models were challenged with a combination of the bacterial toxins LPS and ATP, a release of the proinflammatory cytokines IL-1β and IL-8 was observed, confirming that the model can generate an immune response. In virus inhibition assays with the bioprinted lung model, the replication of a seasonal IAV strain was restricted by treatment with an antiviral agent in a dose-dependent manner. The printed lung construct provides an alveolar model to investigate pulmonary pathogenic biology and to support development of new therapeutics not only for IAV, but also for other viruses. 相似文献
157.
Derbala MF Amer AM Almohanadi M John A Amin A John A Sharma M Alkaabi SR Al Dweik NZ Pasic F Yaqoob R Butt MT Shebl FM 《Journal of viral hepatitis》2011,18(7):e258-e262
Among individuals with chronic hepatitis C virus (HCV) infection, approximately 30% of patients show persistently normal alanine aminotransferase (PNALT). Individuals with PNALT have been historically excluded from antiviral treatment. However, some studies have reported sudden worsening of disease in patients with PNALT, suggesting the need to treat such individuals. To evaluate this further, we compared fibrosis severity and response to treatment in patients with PNALT to patients with abnormal ALT. In addition, we investigated whether liver histology and schistosomiasis affect response to treatment differently in those with PNALT and abnormal ALT. A retrospective cohort study of 176 HCV-Genotype 4 (HCV-G4) patients treated with pegylated interferon (PEG-IFN) and ribavirin. Of 176 cases studied, 53 (30.1%) had normal ALT. Prevalence of pretreatment severe fibrosis, sustained virological response (SVR) and relapse were not significantly different in patients with PNALT (26%, 66% and 5.7% respectively) compared to those with abnormal ALT (32.5%, 60.7%, and 6.6% respectively). Multivariable logistic regression revealed that pretreatment ALT, pretreatment viral load, inflammation and schistosomiasis were not significantly associated with SVR [OR (95% CI), 0.75 (0.34-1.65); 0.92 (0.61-1.37); 1.64 (0.64-4.18); 0.90 (0.44-1.84) respectively]. Severe fibrosis was the only significant predictor of SVR [OR (95% CI), 0.38 (0.14-0.99)]. PNALT does not reflect the degree of fibrotic changes or predict SVR. Furthermore, schistosomiasis is a predictor of neither fibrosis nor poor response in patients with PNALT. Severe fibrosis is a strong and independent predictor of response to treatment. Therefore, it is important to treat individuals with PNALT levels regardless of schistosomiasis. 相似文献
158.
The Editors welcome topical correspondence from readers relating to articles published in the Journal. Responses should be sent electronically via the BJS website ( www.bjs.co.uk ). All letters will be reviewed and, if approved, appear on the website. A selection of these will be edited and published in the Journal. Letters must be no more than 250 words in length. Copyright © 2010 British Journal of Surgery Society Ltd. Published by John Wiley & Sons, Ltd. 相似文献
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