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41.
Ikram Hussain Saba Ishrat Veeraraghavan Meyyur Aravamudan Shahab R. Khan Babu P. Mohan Rahul Lohan Muhammad Bilal Abid Tiing Leong Ang 《Medicine》2022,101(17)
Background:Mesenteric panniculitis (MP) is a non-specific, localized inflammation at the mesentery of small intestines which often gets detected on computed tomography. An association with malignant neoplasms remains unclear. We performed a systematic review and meta-analysis to examine the association of malignancy with MP.Methods:MEDLINE, EMBASE, Web of Science, and Cochrane databases were searched for articles published from inception to 2020 that evaluated the association of malignant neoplasms with MP in comparison with control groups. Using random-effects method, a summary odds ratio (OR) estimate with 95% confidence intervals for malignant neoplasms in MP was estimated.Results:Four case-control studies reporting data on 415 MP patients against 1132 matched-controls met inclusion criteria and were analyzed. The pooled OR for finding a malignant neoplasm in patients with MP was 0.907 (95% CI: 0.688–1.196; P = .489). The heterogeneity was mild and non-significant. Also, there was no heightened risk of any specific type of malignancy with MP. Three more case-series with unmatched-control groups (MP: 282, unmatched-controls: 17,691) were included in a separate analysis where the pooled OR of finding a malignant neoplasm was 2.963 (95% CI: 1.434–6.121; P = .003). There was substantial heterogeneity in this group.Conclusion:This meta-analysis of matched controlled studies proves absence of any significant association of malignant neoplasms with MP. Our study also demonstrates that the putative association of malignancy with MP is mainly driven by uncontrolled studies or case-series. 相似文献
42.
Photocatalytic materials attract immense scientific interest due to their possible applications in energy harvesting. These applications are strongly dependent on the material''s band gap and efficient visible light absorption, which ultimately relies on the underlying electronic structure of the material. In this work, we have theoretically studied the electronic and optical response of a Cu3P semiconductor. We have used Density Functional Theory (DFT), and the Many-Body Perturbation Theory (MBPT) based Bethe–Salpeter Equation (BSE). Cu3P has intriguing band gap nature, as DFT predicts a semi-metallic state which was corrected by employing the Hubbard potentials. Only astronomically large values of Hubbard potentials reproduced the semiconducting state of Cu3P. The optical response of the material is computed within a Random Phase Approximation (RPA) and using the BSE on top of DFT+U wavefunctions and on the ground state computed with the PBE0 functional. The BSE captures the excitonic physics, and the optical absorption obtained from it was red-shifted compared to the RPA, which shows the significance of electron–hole interactions in Cu3P. The comparison of the BSE with experiments suggests that BSE@PBE0 reproduces the optical absorption much more closely to the experimental data.The optical absorption from BSE@PBE0 is in better agreement with the experiment than BSE@DFT+U. The electron–hole interaction and strong correlation between electrons play a vital role in the optoelectronic response of Cu3P. 相似文献
43.
Is Fatimah Sugesti Nur Amaliah Muhammad Fiqri Andrian Tri Pindi Handayani Rico Nurillahi Nurcahyo Iman Prakoso Wiyogo Prio Wicaksono Laemthong Chuenchom 《Sustainable Chemistry and Pharmacy》2019
This research demonstrates the use of biogenic silica derived from bamboo leaf ash as a support for iron oxide nanoparticles. The preparation includes silica extraction from bamboo leaf ash and iron oxide nanoparticle impregnation into the silica gel under hydrothermal conditions, which is followed by calcination at 400 °C for 2 h. The physicochemical characterization includes X-ray diffraction analysis, gas sorption analysis, scanning electron microscopic analysis and transmission electron microscopic analysis. The light absorption capability and the band gap energy of the materials were determined by diffuse-reflectance UV–visible spectrophotometry. The materials obtained by varying the Fe content to 5 and 10% wt. were evaluated in rhodamine B photocatalytic degradation and photooxidation systems. It was found that the materials have a combined hematite and magnetite nanostructure, with the ratio of 9:10, and the particle sizes range from 10 to 40 nm. With a band gap energy of 2.27 eV, the prepared materials produce the successive photocatalytic degradation of rhodamine B. It was clarified that the formation of composite enhances stability and reusability of photocatalyst as shown by the stable initial rate at wide pH range and reuse for 5 cycles. Degradation mechanism is enhanced by the addition of H2O2 as an oxidant, and the investigation of the effect of scavengers shows that the degradation rate not only depends on radical formation but also on other species related to the formation of oxidizing agent. 相似文献
44.
Acute toxic effects of hexavalent chromium [Cr(VI)], a widely recognised carcinogenic, mutagenic and redox active metal, were investigated in isolated hepatocytes of goldfish (Carassius auratus). Exposure to 250 microM Cr(VI) induced a significant decrease of cell viability from 94% in controls to 88% and 84% after 30 min and 4 h of exposure, respectively. Cr-toxicity was associated with a concentration-dependent stimulation of the formation of reactive oxygen species (ROS). As one potential source of ROS formation we identified the lysosomal Fe(2+) pool, since the ferric ion chelator deferoxamin inhibited ROS formation by approximately 15%. Lysosomal membranes remained nevertheless intact during Cr-exposure, as determined from neutral red retention in this compartment. Another significant source of ROS appear to be the mitochondria, where a presumably uncoupled increase of respiration by 20-30% was triggered by the metal. Inhibition of mitochondrial respiration by cyanide caused an approximately 40% decrease of Cr-induced ROS-formation, whereas the uncoupling agent carbonyl cyanide m-chlorophenyl hydrazine was without effect. Cellular Ca(2+) homeostasis was not disturbed by Cr(VI) and thus played no role in this scenario. Overall, our data show that Cr(VI) is acutely toxic to goldfish hepatocytes, and its toxicity is associated with the induction of radical stress, presumably involving lysosomes and mitochondria as important sources of ROS formation. 相似文献
45.
Hammad Ahmed Shah Moncef L. Nehdi Muhammad Imtiaz Khan Usman Akmal Hisham Alabduljabbar Abdullah Mohamed Muhammad Sheraz 《Materials》2022,15(15)
Compressive strength (CS) and splitting tensile strength (STS) are paramount parameters in the design of reinforced concrete structures and are required by pertinent standard provisions. Robust prediction models for these properties can save time and cost by reducing the number of laboratory trial batches and experiments needed to generate suitable design data. Silica fume (SF) is often used in concrete owing to its substantial enhancements of the engineering properties of concrete and its environmental benefits. In the present study, the M5P model tree algorithm was used to develop models for the prediction of the CS and STS of concrete incorporating SF. Accordingly, large databases comprising 796 data points for CS and 156 data records for STS were compiled from peer-reviewed published literature. The predictions of the M5P models were compared with linear regression analysis and gene expression programming. Different statistical metrics, including the coefficient of determination, correlation coefficient, root mean squared error, mean absolute error, relative squared error, and discrepancy ratio, were deployed to appraise the performance of the developed models. Moreover, parametric analysis was carried out to investigate the influence of different input parameters, such as the SF content, water-to-binder ratio, and age of the specimen, on the CS and STS. The trained models offer a rapid and accurate tool that can assist the designer in the effective proportioning of silica fume concrete. 相似文献
46.
Aseel Eid Isha Mhatre-Winters Ferass M. Sammoura Melissa K. Edler Richard von Stein Muhammad M. Hossain Yoonhee Han Miriam Lisci Kristina Carney Mary Konsolaki Ronald P. Hart Joan W. Bennett Jason R. Richardson 《Environmental health perspectives》2022,130(8)
Background: The interaction of aging-related, genetic, and environmental factors is thought to contribute to the etiology of late-onset, sporadic Alzheimer’s disease (AD). We previously reported that serum levels of p,p′-dichlorodiphenyldichloroethylene (DDE), a long-lasting metabolite of the organochlorine pesticide dichlorodiphenyltrichloroethane (DDT), were significantly elevated in patients with AD and associated with the risk of AD diagnosis. However, the mechanism by which DDT may contribute to AD pathogenesis is unknown.Objectives: This study sought to assess effects of DDT exposure on the amyloid pathway in multiple in vitro and in vivo models.Methods: Cultured cells (SH-SY5Y and primary neurons), transgenic flies overexpressing amyloid beta (), and C57BL/6J and 3xTG-AD mice were treated with DDT to assess impacts on the amyloid pathway. Real time quantitative polymerase chain reaction, multiplex assay, western immunoblotting and immunohistochemical methods were used to assess the effects of DDT on amyloid precursor protein (APP) and other contributors to amyloid processing and deposition.Results: Exposure to DDT revealed significantly higher APP mRNA and protein levels in immortalized and primary neurons, as well as in wild-type and AD-models. This was accompanied by higher levels of secreted in SH-SY5Y cells, an effect abolished by the sodium channel antagonist tetrodotoxin. Transgenic flies and 3xTG-AD mice had more pathology following DDT exposure. Furthermore, loss of the synaptic markers synaptophysin and PSD95 were observed in the cortex of the brains of 3xTG-AD mice.Discussion: Sporadic Alzheimer’s disease risk involves contributions from genetic and environmental factors. Here, we used multiple model systems, including primary neurons, transgenic flies, and mice to demonstrate the effects of DDT on APP and its pathological product . These data, combined with our previous epidemiological findings, provide a mechanistic framework by which DDT exposure may contribute to increased risk of AD by impacting the amyloid pathway. https://doi.org/10.1289/ EHP10576相似文献
47.
Purpose:This study aims to facilitate researchers’ and clinicians’ understanding of research frontiers and trends in nocturia. It explores the scientific research outcomes and key bibliometric indices and plots global research on nocturia.Methods:A bibliometric retrospective study was designed, and an online search was conducted in the Web of Science Core Collection database using the potential search keywords related to nocturia in the title field with some specific filtration. HistCite™ and VOSviewer software for windows were used to analyze the data obtained for authors, journals, countries, institutions, keywords, and visualization mapping.Results:The initial search retrieved 1479 hits. A total of 1445 publications were included in the final analysis. Of these, 43.53% were published as articles. The most studied area in nocturia is urology nephrology. The most productive year was 2019 (n = 121, citations = 335), and the most prolific author, both in terms of publications (n = 97) and citations (1658) was Weiss JP. The most cited journal in nocturia research was the Journal of Urology (n = 293, citations = 3050). The most widely used keyword in nocturia publications was nocturia (n = 1249). Visualization mapping shows that the USA was the most influential and highly cited country in nocturia research.Conclusion:This study showed that there has been an increasing research trend in nocturia over the past few years. The current findings provide important empirical evidence for researchers, clinicians, and physicians to understand research frontiers and trends, achievements, collaborative networks, and hotspot research topics in the research field of nocturia. 相似文献
48.
Abbasi MR Sparano JA Sarta C Wiernik PH 《Medical oncology (Northwood, London, England)》2003,20(1):53-58
Fludarabine is an active agent in low-grade non-Hodgkin’s lymphoma and chronic lymphocytic leukemia. Paclitaxel is also active
in patients with refractory lymphoma, and preclinical data suggest an additive effect with fludarabine in vitro. We performed
a phase I trial of fludarabine (25 mg/m2 d 1–3) plus a 3-h infusion of paclitaxel (125, 150, or 175 mg/m2) on d 3 every 28 d in 13 patients with non-Hodgkin’s lymphoma. The paclitaxel dose was escalated in cohorts of 3–4 patients
using standard phase I design schema. Dose-limiting toxicity was defined as febrile neutropenia, platelet nadir less than
50,000/μL, or grade 3–4 nonhematologic toxicity.
Thirteen patients were accrued to the study, 8 of these 13 patients (62%) had received prior chemotherapy. At the 125-, 150-,
and 175-mg/m2 dose levels of paclitaxel, dose-limiting toxicity occurred in 1/4, 0/4, and 0/4 patients, respectively. The single patient
with dose-limiting toxicity had febrile neutropenia. Partial response occurred in two of eight patients with low-grade lymphoma
and none of five patients with other types of lymphoma. A paclitaxel dose of 175 mg/m2 given as a 3-h infusion on d 3 in conjunction with fludarabine (25 mg/m2 d 1–3 every 4 wk) is a well-tolerated regimen for non-Hodgkin’s lymphoma. Further study will be required in order to determine
whether the fludarabine-paclitaxel is more active than fludarabine alone in patients with low-grade lymphoma and chronic lymphocytic
leukemia. 相似文献
49.
50.
AIM OF THE STUDY: The present study was aimed at documentation of botanical anthelmintics used in the traditional veterinary practices in Sahiwal district of Punjab, Pakistan. MATERIALS AND METHODS: In rapid rural appraisal, 331 traditional veterinary healers (TVH) were identified as key respondents in the study area followed by participatory rural appraisal for data collection using a well-structured questionnaire. Information was collected through interviews, focused group discussions and field visits over a period of 2 years. RESULTS: A total of 49 traditional recipes, with 41 plant species representing 39 genera and 27 families, were recorded for the treatment of helminthosis in animals. Most frequently used plants (>/=5 times) were Brassica campestris L. and Mallotus philippinensis (Lam.) Muell.-Arg. and most frequently used families (>/=5 times) were Brassicaceae, Euphorbiaceae and Solanaceae. Most frequently used part of the plant was leaves (n=10) followed in order by seeds (n=9), whole fruit (n=5), aerial parts and whole plant (n=4), fruit (n=3), bulb (n=2) and bark, rhizome, stem, stem plus root and twigs (n=1). Five recipes out of 49 (10.2%) contained more than one plant species and rest 44 (89.8%) contained single plant species. CONCLUSIONS: Twenty out of 41 plants (48.78%) are reported for the first time for their traditional use as anthelmintics in Pakistan. Further studies on pharmacokinetics using scientific procedures may prove these plants as promising candidates for their future use as anthelmintics. 相似文献