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31.
H O Goyal T D Braden C S Williams P Dalvi M Mansour J W Williams 《Toxicological sciences》2005,87(1):242-254
We previously reported that diethylstilbestrol (DES) or estradiol valerate (EV) exposure at a dose of 0.10-0.12 mg/kg, or higher, per day, on alternate days, from postnatal days 2-12, resulted in abnormal penis development and infertility (H. O. Goyal et al., 2005, J. Androl. 26, 32-43). The objective of this study was to identify a critical developmental period(s) during which EV exposure results in the observed penile abnormalities. Male pups received EV at a dose of 0.10-0.12 mg/kg on postnatal day(s) 1, 1-3, 4-6, 1-6, 7-12, 13-18, 19-24, or 25-30. Fertility was tested at 102-115 days of age and tissues were examined at 117-137 days. Both penile morphology and fertility were unaltered in rats treated with EV after 12 days of age. Conversely, except in rats treated on postnatal day 1 only, none of the males treated prior to 12 days of age sired pups, and all had abnormal penises, including varying degrees of abnormal accumulation of fat cells and loss of cavernous spaces and smooth muscle cells in the corpora cavernosa penis, which were maximal in the 1-6-day group. Also, the preputial sheath was partially released or its release was delayed, and the weight of the bulbospongiosus muscle was significantly reduced. Plasma testosterone (T) in the 1-6- and 4-6-day groups and intratesticular T in the 4-6-day group were significantly lower. The testosterone surge, characteristic of controls in the first week of life, was suppressed in the 1-3-day group. Estrogen receptor alpha mRNA expression was enhanced in the body of the penis in the 1-3-day group, but not in the 13-18-day group. Hence, EV exposure prior to 12 days of age (as short as 1-3 days postnatal), but not after 12 days of age, results in long-term abnormal penile morphology, characterized by abnormal accumulation of fat cells in the corpora cavernosa penis and, consequently, loss of fertility. 相似文献
32.
Background: Due to Russia and Ukraine’s key roles in supplying cereals and oilseeds, the Russia–Ukraine war intensifies the current food availability and price challenges in Lebanon, which is a major wheat importer. Given these constraints, we conducted this study to assess the prevalence and correlates of food insecurity, low dietary diversity (DD), unhealthy dietary patterns, and the shifts in households’ food-related habits in response to the Russia–Ukraine war among a representative sample of Lebanese household’s members aged 18 years and above (N = 914). Methods: Data were collected between June and July 2022 using self-administered questionnaires; Results: Findings showed that nearly half of the households consume an undiversified diet (46%), and 55.3% ate fewer than two meals per day. The prevalence of food insecurity among Lebanese households was 74%, with one in every four households being severely food insecure. In addition, the majority of households’ members went out shopping and purchased food less than the pre-war period (68.7% and 70.3%, respectively). Furthermore, almost 68.3% of households’ members highlighted price increases for cereal products, which were the least available and most stocked items. Findings obtained through binary logistic regression also showed that food insecurity was two times higher among households with low monthly income, 35% higher among females, and three times higher among married participants; Conclusions: The impact of the Russia–Ukraine conflict on food security in Lebanon requires a systems-thinking approach as well as international effort to understand the challenges and find solutions to minimize the war’s negative effects. 相似文献
33.
This study is to demonstrate the effect of multimodal fusion on the performance of deep learning artery-vein (AV) segmentation in optical coherence tomography (OCT) and OCT angiography (OCTA); and to explore OCT/OCTA characteristics used in the deep learning AV segmentation. We quantitatively evaluated multimodal architectures with early and late OCT-OCTA fusions, compared to the unimodal architectures with OCT-only and OCTA-only inputs. The OCTA-only architecture, early OCT-OCTA fusion architecture, and late OCT-OCTA fusion architecture yielded competitive performances. For the 6 mm×6 mm and 3 mm×3 mm datasets, the late fusion architecture achieved an overall accuracy of 96.02% and 94.00%, slightly better than the OCTA-only architecture which achieved an overall accuracy of 95.76% and 93.79%. 6 mm×6 mm OCTA images show AV information at pre-capillary level structure, while 3 mm×3 mm OCTA images reveal AV information at capillary level detail. In order to interpret the deep learning performance, saliency maps were produced to identify OCT/OCTA image characteristics for AV segmentation. Comparative OCT and OCTA saliency maps support the capillary-free zone as one of the possible features for AV segmentation in OCTA. The deep learning network MF-AV-Net used in this study is available on GitHub for open access. 相似文献
34.
Factors affecting single-step transepithelial photorefractive keratectomy outcome in the treatment of mild, moderate, and high myopia: a cohort study 下载免费PDF全文
Mansour M. Al-Mohaimeed 《国际眼科》2022,15(5):786-792
AIM: To investigate the effect of preoperative factors on visual acuity, higher-order aberrations (HOAs), and index of success for spherical change (S.IOS) after transepithelial photorefractive keratectomy (t-PRK) for treating different grades of myopia.
METHODS: This was a retrospective one-armed cohort study where patients with high, moderate, or mild myopia treated with single-step t-PRK using Amaris 500 Hz excimer laser were evaluated for visual acuity, refractive status, corneal topography, HOAs, S.IOS, and mean efficiency and safety index before and 6mo after surgery.
RESULTS: A total of 154 eyes of 77 patients with mild (n=59), moderate (n=83), and high (n=12) myopia were reviewed. The efficiency and safety indices for vision recovery by single-step t-PRK were 98% and 100%, respectively. The achieved spherical equivalent (SE) was within 1 diopter (D) in 151 (98%) eyes. The median of the S.IOS was 1.18 [interquartile range (IQR) 1.0, 1.4]. The change in S.IOS was significantly correlated with age (P=0.007), 6.5 mm ablation zone (Mann-Whitney U test, P<0.01), and mild and moderate grade of myopia (Kruskal–Wallis test, P<0.001). Trefoil aberration, spherical aberration, and aberration coefficient types of HOA increased significantly (Wilcoxon test, P<0.001) 6mo post-surgery. There was a significant correlation between spherical aberration and aberration coefficient HOAs by myopia grades (P<0.05).
CONCLUSION: Single-step t-PRK has promising short-term outcomes for refractive corrections and vision improvement to treat all three grades of myopia. 相似文献
35.
Donald H. Lein Jr. Mansour Alotaibi Marzouq Almutairi Harshvardhan Singh 《International Journal of Sports Physical Therapy》2022,17(5):907
BackgroundClinicians often use physical performance tests (PPT) to measure performance measures in sports since they are easy to administer, portable, and cost-efficient. However, PPT often lack good or known psychometric properties. Perhaps, the 30-second chair-stand test (30CST) would be a good functional test in athletic populations as it has been shown to demonstrate good psychometric properties in older adults.Hypothesis/PurposeThe purpose of this study was to determine normative values for and concurrent, convergent and discriminative validity of 30CST for healthy young adults aged 19-35 years.Study DesignCross-sectionalMethodsEighty-one participants completed this study. All participants performed two trials of 30CST, 5-times sit-to-stand (5xSTS), and lateral step-up test (LSUT). Investigators used the International Physical Activity Questionnaire Leisure Domain (LD-IPAQ) to divide participants into insufficiently or sufficiently active groups based on the weekly metabolic equivalent of task per the Physical Activity Guidelines for Americans.ResultsParticipants (Mean + SD age, 25.1 ± 3.4 years; body height, 1.71 ± 0.09 m; body mass, 72.6 ± 16.1 kg; females 47) performed an average of 33.0±5.4 30CST repetitions. The 30CST performance was negatively associated with 5xSTS (r=-0.79 p=0.01) and positively associated with LSUT performances (r=0.51, p=0.01) when using Pearson correlations. In addition, the sufficiently active group performed significantly greater 30CST repetitions than the insufficiently active group (mean difference = 2.5; p=0.04).ConclusionsIn addition to finding a reference value for 30CST performance in young adults, investigators found that the 30CST displayed concurrent and convergent validity in assessing functional lower extremity (LE) muscle strength and discriminated between those with sufficient and insufficient physical activity levels. Training and rehabilitation professionals could use the 30CST for testing functional LE muscle strength for athletes in pre-season or during rehabilitation. Future investigators should perform studies to determine if 30CST predicts sport performance.Level of EvidenceLevel 2 相似文献
36.
Khaled Ahmed Mansour Ahmed Elbermawi Ahmed A. Al-Karmalawy Mohamed-Farid Lahloub Mona El-Neketi 《Pharmaceutical biology》2022,60(1):1374
ContextTraditionally, Oleaceae plants are used to treat many diseases, such as rheumatism, hypercholesterolaemia, or ulcers.ObjectivesTo investigate the cytotoxic potential of Jasminum humile L., Jasminum grandiflorum L., and Olea europaea L. (Oleaceae) extracts against selected human cancer cells lines, followed by a phytochemical investigation of the most potent one.Materials and methodsThe 95% ethanol extracts of aerial parts of three oleaceous plants were examined for their cytotoxicity against HepG-2, MCF-7, and THP-1 cell lines using MTT assay and doxorubicin (positive control). J. humile was bio-selected and submitted to bio-guided fractionation. Chromatographic workup of ethyl acetate and n-butanol fractions afforded two new compounds; 1-methoxyjasmigenin (1) and 1-methyl-9-aldojasmigenin (2), along with five known ones (3–7). Structures were unambiguously elucidated using 1D/2D NMR and ESI-HRMS. Isolated compounds were assessed for their anti-proliferative potential, and both selectivity index and statistical significance were determined. Molecular docking was conducted against the Mcl-1 receptor using (AZD5991) as a standard.ResultsJasmoside (5) was the most potent anticancer compound showing IC50 values of 66.47, 41.32, and 27.59 µg/mL against HepG-2, MCF-7, and THP-1 cell lines, respectively. Moreover, isojasminin (4) exhibited IC50 values of 33.49, 43.12, and 51.07 µg/mL against the same cell lines, respectively. Interestingly, 5 exhibited the highest selectivity index towards MCF-7 and THP-1, even greater than doxorubicin. Molecular docking results were in full agreement with the MTT assay and the proposed SAR.ConclusionIn this study, two new compounds were purified. The biological activity highlighted jasmoside (5) as a lead anticancer drug for further future investigation. 相似文献
37.
Fahimeh Vafaee Samira Mandizadeh Omid Amiri Mansour Jahangiri Masoud Salavati-Niasari 《RSC advances》2022,12(32):20973
Correction for ‘Synthesis and characterization of AFe2O4 (A: Ni, Co, Mg)–silica nanocomposites and their application for the removal of dibenzothiophene (DBT) by an adsorption process: kinetics, isotherms and experimental design’ by Fahimeh Vafaee et al., RSC Adv., 2021, 11, 22661–22676, https://doi.org/10.1039/D1RA02780H.The authors regret an error in Fig. 4 where a section of the XRD for 4(a) and (b) is identical.Open in a separate windowFig. 4(a) The XRD pattern of sample 3 after adsorption of DBT. (b) The XRD pattern of sample 3 before adsorption of DBT.The authors have repeated the experiment and provided new data for Fig. 4. An independent expert has viewed the new data and has concluded that it is consistent with the discussions and conclusions presented. The correct Fig. 4 is shown below:The Royal Society of Chemistry apologises for these errors and any consequent inconvenience to authors and readers. 相似文献
38.
Sulfate-induced expansion resulting from the formation of ettringite in sulfate-bearing soil stabilised with calcium-based stabilisers is a problematic issue with technical and economic implications. Thus, this research examines the viability of the co-addition of lime (L) and silica fume (S) at varying binder dosages (4, 6, and 10 wt%), with a view of establishing the optimum blend of L–S for suppressing the ettringite-induced expansion of artificially high sulfate-dosed soil (kaolinite-K and gypsum-G). To do so, a series of laboratory specimens, designed using different gypsum and lime concentrations, were investigated using unconfined compression strength (UCS), linear expansion, and derivative thermo-gravimetric analysis (DTG) as the main criteria for the examination. The research outcomes indicated that the increasing substitution of L with S induces a gradual reduction on the UCS and linear expansion at binder levels of 4 and 6 wt%, while its usage in a high binder level (10 wt%), can yield an expansion reduction, with no compromise on the UCS performance. Therefore, silica fume has the potential for restricting ettringite formation and suppressing the expansion, of which 3L7S is the optimum blending ratio for suppressing the expansion. 相似文献
39.
40.
Effectiveness of prevention of SARS-CoV-2 transmission among unvaccinated Italian healthcare workers
Giulia Collatuzzo Ihab Mansour Catalina Ciocan Giorgia Ditano Alessandro Godono Paola Rossello Maurizio Coggiola Enrico Pira Paolo Boffetta Working Group on Sars-CoV- prevention 《La Medicina del lavoro》2022,113(6)
Background:We aimed to investigate the association between personal protective equipment (PPE) use and SARS-CoV-2 infection among healthcare workers (HCWs).Methods:We analyzed occupational surveillance contact forms followed by a PCR test notified between March and September 2020 by Italian HCWs. The odds ratios (ORs) and 95% Confidence Intervals (CIs) for positive PCR based on HCWs and contacts characteristics were calculated through multivariable logistic regression models. When multiple contacts were potentially effective for a PCR test, they were weighted by the inverse of their number.Results:Overall, 4,883 contacts reported by 2,952 HCWs were analyzed, and 224 contacts among 144 HCWs had positive PCR. No difference was found according to sex, age, employment, or job title, except for an OR of 0.30 (95%CI 0.11-0.78) for resident physicians, compared to administrative staff. The ORs for use of surgical mask were 0.59 (95%CI=0.40-0.86) for use only by HCW, 0.49 (95%CI=0.22-1.07) only by the infected person, and 0.40 (95%CI=0.27-0.60) by both, compared to use by neither. Use of other PPEs was not associated with infection, while the OR for hand sanitation was 0.61 (95%CI=0.40-0.93). HCWs reporting fever, cough, and asthenia had a higher risk of infection.Conclusions:Use of surgical masks was associated with a 40-60% lower risk of infection, especially when both HCWs and infected individuals used them. Our results quantify the role played by mask use and hand sanitation in preventing SARS-CoV-2 transmission in high-risk circumstances. 相似文献