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91.
Assessment of parafoveal cone density in patients taking hydroxychloroquine in the absence of clinically documented retinal toxicity
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92.
Masrudin Md Yusoff Noorfatimah Yahaya Noorashikin Md Saleh Muggundha Raoov 《RSC advances》2018,8(45):25617
This study investigated the effectiveness of ionic liquids (ILs) loaded onto the surface of a polymeric adsorbent (βCD-TDI) grafted with modified magnetic nanoparticles (MNPs) via an analysis of water treatment, which resulted in high removal of selected endocrine-disrupting chemicals (parabens). The syntheses of MNPs, MNP-βCD-TDI, and IL-MNP-βCD-TDI were characterised and compared using Fourier transform infrared (FT-IR) spectroscopy, carbon–hydrogen–nitrogen (CHN) analysis, vibrating sample magnetometry (VSM), scanning electron microscopy (SEM), transmission electron microscopy (TEM), the Brunauer–Emmett–Teller (BET) method, thermogravimetric analysis (TGA), and X-ray diffraction (XRD). The results of SEM and TEM indicated that the pore size distribution exhibited mesoporous characteristics with a small surface area (BET analysis: 42.95 m2 g−1). Furthermore, a preliminary sorption experiment demonstrated the ability of IL-MNP-βCD-TDI to enhance not only the sorption capacity, but also the removal of propyl paraben (PP), butyl paraben (BP), and benzyl paraben (ArP). The adsorption process appeared to be pH-dependent, and hence the optimum pH of 6 was selected for a subsequent batch adsorption study of all the studied parabens with an equilibrium time of 80 min. Next, in an attempt to investigate the interactions that occur between the adsorbent and the adsorbates, adsorption kinetics and isotherm studies were performed. All the studied parabens were found to best fit pseudo-second-order kinetics and the Freundlich isotherm with R2 > 0.98 at room temperature (298 K). The interaction of the host–guest inclusion complex and the π–π interaction between βCD and a selected paraben compound (ArP) were identified by performing 1H nuclear magnetic resonance (NMR), together with ultraviolet-visible (UV-vis) spectroscopic analysis. Finally, the adsorption efficiency of the developed material was practically tested on tap water, drain water, and industrial wastewater, which revealed a significant removal of parabens of up to 60–90% in comparison with a prior analysis.The main interaction between the synthesized material and the targeted paraben compounds. 相似文献
93.
Al-Herz Adeeba Saleh Khuloud Al-Awadhi Adel Al-Kandari Waleed Hasan Eman Ghanem Aqeel Hussain Mohammed Ali Yaser Nahar Ebrahim Alenizi Ahmad Hayat Sawsan Abutiban Fatemah Aldei Ali Alhajeri Hebah Alhadhood Naser Bahbahani Husain Tarakmeh Hoda Mokaddem Khaled Khadrawy Ahmad Fazal Ammad Zaman Agaz Mazloum Ghada Bartella Youssef Hamed Sally Alsouk Ramia Al-Saber Ahmed 《Clinical rheumatology》2021,40(5):1759-1765
Clinical Rheumatology - Biologics are indicated in rheumatoid arthritis (RA) in case of persistent high disease activity despite conventional disease-modifying anti-rheumatic drugs (cDMARDs) or... 相似文献
94.
Parth Makker MD Moussa Saleh MD Aditi S. Vaishnav MBBS Kristie M. Coleman RN Stuart Beldner MD Haisam Ismail MD Nikhil Sharma MD Ram Jadonath MD Bruce Goldner MD Raman Mitra MD PhD Laurence Epstein MD Roy John MD Stavros E. Mountantonakis MD 《Journal of cardiovascular electrophysiology》2021,32(6):1658-1664
95.
Roy S Sharom JR Houde C Loisel TP Vaillancourt JP Shao W Saleh M Nicholson DW 《Proceedings of the National Academy of Sciences of the United States of America》2008,105(11):4133-4138
Caspase-12 is a dominant-negative regulator of caspase-1 (IL-1beta-converting enzyme) and an attenuator of cytokine responsiveness to septic infections. This molecular role for caspase-12 appears to be akin to the role of cFLIP in regulating caspase-8 in the extrinsic cell death pathway; however, unlike cFLIP/Usurpin, we demonstrate here that caspase-12 is catalytically competent. To examine these catalytic properties, rat caspase-12 was cloned, and the recombinant enzyme was used to examine the cleavage of macromolecular and synthetic fluorogenic substrates. Although caspase-12 could mediate autoproteolytic maturation of its own proenzyme, in both cis and trans, it was not able to cleave any other polypeptide substrate, including other caspase proenzymes, apoptotic substrates, cytokine precursors, or proteins in the endoplasmic reticulum that normally undergo caspase-mediated proteolysis. The dearth of potential substrates for caspase-12 also was confirmed by whole-cell diagonal-gel analysis. Autolytic cleavage within the caspase-12 proenzyme was mapped to a single site at the large-small subunit junction, ATAD(319), and this motif was recognized by caspase-12 when incorporated into synthetic fluorogenic substrates. The specific activity of caspase-12 with these substates was several orders of magnitude lower than caspases-1 and -3, highlighting its relative catalytic paucity. In intact cells, caspase-12 autoproteolysis occurred in the inhibitory complex containing caspase-1. We propose that the proteolytic activity of caspase-12 is confined to its own proenzyme and that autocleavage within the caspase-1 complex may be a means for temporal limitation of the inhibitory effects of caspase-12 on proinflammatory cytokine maturation. 相似文献
96.
Urinary tetrahydroaldosterone as a screening method for primary aldosteronism: a comparative study 总被引:2,自引:0,他引:2
Abdelhamid S Blomer R Hommel G Haack D Lewicka S Fiegel P Krumme B 《American journal of hypertension》2003,16(7):522-530
BACKGROUND: The major aldosterone metabolite 3 alpha,5 beta tetrahydroaldosterone reflects up to 45% of the aldosterone secretion. Its 24-h urinary excretion is likely to provide an accurate index of the daily aldosterone production and to be an indicator for primary aldosteronism (PA). METHODS: In a prospective study, the validity of tetrahydroaldosterone as a screening test for PA was evaluated in comparison to serum potassium, plasma aldosterone, plasma renin activity, plasma aldosterone/renin activity ratio (PARR), as well as 24-h urinary aldosterone-18-glucuronide and free aldosterone. A total of 111 normotensive individuals, 412 PA patients and 1453 essential hypertensive patients, were studied. The effect of blood sampling technique on potassium level was also investigated. RESULTS: Tetrahydroaldosterone differentiated PA from essential hypertension with a sensitivity of 96% and a specificity of 95%. The sensitivity was 89% for plasma aldosterone, 87% for free aldosterone, 85% for PARR, 71% for aldosterone-18-glucuronide and 51% for renin activity. Specificities varied between 91% and 85%. The combined use of the parameters plasma aldosterone > or =9.0 ng/dL and PARR > or =25 resulted in a sensitivity of 82% and specificity of 95%. Forearm exercise proved to be a source of erroneous elevations of potassium sufficient to obscure the suspicion of PA. CONCLUSION: The data suggest that tetrahydroaldosterone is the most reliable screening test for PA. Tetrahydroaldosterone determination in combination with aldosterone-18-glucuronide and free aldosterone increases diagnostic specificity for PA. Potassium, renin, plasma aldosterone, and basal PARR are inadequate screening procedures because they are subject to high rates of false-positive and false-negative results. 相似文献
97.
Ashish I. Vaska Saleh Abbas 《HPB : the official journal of the International Hepato Pancreato Biliary Association》2019,21(2):148-156
Background
Bile leak following liver resection can be associated with significant morbidity. This systematic review and meta-analysis aims to evaluate the effect of intraoperative bile leak testing on postoperative bile leak rate and other complications after liver resection without biliary reconstruction for any cause.Methods
PubMed, MEDLINE, Embase, Cochrane Library and grey literature databases were searched for articles between 1960 and 2017 comparing bile leak rates with or without bile leak testing. Standard meta-analysis methods were used. The primary outcome was bile leak rate, and secondary outcomes were overall morbidity, reintervention rate and length of stay.Results
8 articles met inclusion criteria. Intraoperative bile leak testing after resection was associated with lower postoperative bile leak rate (4.1% vs 12.3%, OR 0.36, 95% CI 0.23–0.55, p < 0.001), overall morbidity (OR 0.67, 95% CI 0.47–0.96, p = 0.030), need for reintervention (OR 0.11, 95% CI 0.03–0.36, p < 0.001) and a shorter duration of hospital stay (2.21 days, 95% CI 0.69–3.73, p = 0.004).Conclusion
The routine use of intraoperative bile leak testing during liver resection results in a significant reduction in postoperative bile leak rate, overall morbidity, length of hospital stay and need for re-intervention. Bile leak testing should be performed after liver resection without biliary reconstruction. 相似文献98.
Patients with breast carcinomas of the invasive cribriform (IC) histological type often have excellent prognosis. Nevertheless, prognostic markers such as CD44v3, v4, and v6 isoforms have never been evaluated in this histological type. Cases seen between 1996 and 2006 at two major public hospitals in Kuwait were reviewed. We selected the cases which still had enough tissue in the paraffin blocks, had pure rather than mixed typical histological type, did not receive hormonal or any other type of therapy prior to or at the time the tumor was excised, and which were grade 1, and stage IIA (T2, N0, M0). This is to control for confounding factors that could affect the degree of tumor expression of the above isoforms. Sections were immunostained using a highly sensitive roxidase-anti-peroxidase kit, and scoring of immunostaining was performed in a semi-quantitative manner as established in the literature. An extensive expression of the CD44v3 and v6 isoforms was seen in 83.3% of the IC tumours, while 83.3% lacked the expression of the v4 isoform. A significant association between the histological type and degree of expression of CD44 isoforms was found only with the v3 isoform. The degree of expression of the v3 isoform was significantly different in the IC tumors as compared to the papillary, invasive lobular, and invasive ductal (NOS) ones. There was a significant negative correlation (rs= - 0.201) between the expression of the v4 and v6 isoforms. IC tumors seem to have a strong expression of the prognostic markers v3 and v6 isoforms of the transmembrane molecule CD44, and to lack the expression of the v4 isoform. 相似文献
99.
Salman M. Toor Reem Saleh Varun Sasidharan Nair Rowaida Z. Taha Eyad Elkord 《Immunology》2021,162(1):30-43
Coronavirus disease 2019 (COVID‐19) is caused by SARS‐CoV‐2, a novel coronavirus strain. Some studies suggest that COVID‐19 could be an immune‐related disease, and failure of effective immune responses in initial stages of viral infection could contribute to systemic inflammation and tissue damage, leading to worse disease outcomes. T cells can act as a double‐edge sword with both pro‐ and anti‐roles in the progression of COVID‐19. Thus, better understanding of their roles in immune responses to SARS‐CoV‐2 infection is crucial. T cells primarily react to the spike protein on the coronavirus to initiate antiviral immunity; however, T‐cell responses can be suboptimal, impaired or excessive in severe COVID‐19 patients. This review focuses on the multifaceted roles of T cells in COVID‐19 pathogenesis and rationalizes their significance in eliciting appropriate antiviral immune responses in COVID‐19 patients and unexposed individuals. In addition, we summarize the potential therapeutic approaches related to T cells to treat COVID‐19 patients. These include adoptive T‐cell therapies, vaccines activating T‐cell responses, recombinant cytokines, Th1 activators and Th17 blockers, and potential utilization of immune checkpoint inhibitors alone or in combination with anti‐inflammatory drugs to improve antiviral T‐cell responses against SARS‐CoV‐2. 相似文献