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21.
Sathish Paramasivan Ahmed Bassiouni Arron Shiffer Matthew R. Dillon Emily K. Cope Clare Cooksley Mahnaz Ramezanpour Sophia Moraitis Mohammad Javed Ali Benjamin Bleier Claudio Callejas Marjolein E. Cornet Richard G. Douglas Daniel Dutra Christos Georgalas Richard J. Harvey Peter H. Hwang Amber U. Luong Rodney J. Schlosser Pongsakorn Tantilipikorn Marc A. Tewfik Sarah Vreugde Peter-John Wormald J. Gregory Caporaso Alkis J. Psaltis 《Allergy》2020,75(8):2037-2049
The sinonasal microbiome remains poorly defined, with our current knowledge based on a few cohort studies whose findings are inconsistent. Furthermore, the variability of the sinus microbiome across geographical divides remains unexplored. We characterize the sinonasal microbiome and its geographical variations in both health and disease using 16S rRNA gene sequencing of 410 individuals from across the world. Although the sinus microbial ecology is highly variable between individuals, we identify a core microbiome comprised of Corynebacterium, Staphylococcus, Streptococcus, Haemophilus and Moraxella species in both healthy and chronic rhinosinusitis (CRS) cohorts. Corynebacterium (mean relative abundance = 44.02%) and Staphylococcus (mean relative abundance = 27.34%) appear particularly dominant in the majority of patients sampled. Amongst patients suffering from CRS with nasal polyps, a statistically significant reduction in relative abundance of Corynebacterium (40.29% vs 50.43%; P = .02) was identified. Despite some measured differences in microbiome composition and diversity between some of the participating centres in our cohort, these differences would not alter the general pattern of core organisms described. Nevertheless, atypical or unusual organisms reported in short-read amplicon sequencing studies and that are not part of the core microbiome should be interpreted with caution. The delineation of the sinonasal microbiome and standardized methodology described within our study will enable further characterization and translational application of the sinus microbiota. 相似文献
22.
Mahnaz Khanavi Mansoureh Sabbagh-Bani-Azad Amir Hossein Abdolghaffari Mahdi Vazirian Isa Isazadeh Mohammad Amin Rezvanfar Maryam Baeeri Azadeh Mohammadirad Roja Rahimi Mohammad Reza Shams-Ardekani Mohammad Abdollahi 《Archives of Medical Science》2014,10(6):1225-1234
Introduction
In this study we investigated the effect of gall of Quercus brantii Lindl., a traditional Iranian medicine, in a murine model of experimental colitis induced in male rats by rectal administration of 2,4,6-trinitrobenzene sulfonic acid (TNBS).Material and methods
Quantification of the main active components was done for estimation of total phenolic content and free gallic acid. Gall of Quercus brantii Lindl. in two forms (gall powder and gall hydro alcoholic extract) was gavaged for 10 days (500 mg/kg). Ten days after induction of colitis, colonic status was examined by macroscopic, microscopic and biochemical analyses. Colonic tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) were analyzed as biomarkers of inflammatory condition. To determine the role of oxidative stress (OS) in colitis, the levels of cellular lipid peroxidation (LPO), total antioxidant power (TAP) and myeloperoxidase (MPO) were measured in colon tissues.Results
TNBS-induced colitis exhibited a significant increase in colon MPO activity and concentrations of cellular LPO, TNF-α and IL-1β, while TAP was significantly reduced. Microscopic evaluations of the colonic damage in the colitis group revealed multifocal degenerative changes in the epithelial lining and areas of necrosis, extensive mucosal and sub-mucosal damage with congested blood vessels, edema and hemorrhages along with extensive infiltration of inflammatory cells. Parameters including macroscopic and microscopic scores, TNF-α, IL-1β, LPO, TAP and MPO improved by both gall extract and gall powder of Quercus brantii Lindl. and reached close to normal levels. The level of total phenols (GAE/100 g of sample) and free gallic acid were estimated to be 88.43 ±7.23 (mean ± SD) and 3.74% of dry weight, respectively.Conclusions
The present study indicates that the gall of Quercus brantii Lindl. is able to exert antioxidative and anti-inflammatory effects on the biochemical and pathological parameters of colitis. 相似文献23.
Firouze Hatami Mohammad Mahdi Rabiei Farid Javandoust Gharehbagh Mohamad Amin Pourhoseingholi Shahram Sabeti Mahnaz Kheyrian Ilad Alavi Darazam 《Journal of clinical laboratory analysis》2022,36(2)
IntroductionRT‐PCR is widely used as a diagnostic test for the detection of SARS‐CoV‐2. In this study, we aim to describe the clinical utility of serial PCR testing in the final detection of COVID‐19.MethodWe collected multiple nasopharyngeal swab samples from patients who had negative RT‐PCR test on the first day after hospitalization. RT‐PCR tests were performed on the second day for all patients with initial negative result. For the patients with secondary negative results on day 2, tertiary RT‐PCR tests were performed on day 3 after hospitalization.ResultAmong 68 patients with initial negative test results, at the end of follow‐up, the mortality number was 20 (29.4%). About 33.8% of patients had subsequent positive PCR test results for the second time and 17.4% of the patients who performed third PCR test had positive result.ConclusionBased on this study, serial RT‐PCR testing is unlikely to yield additional information. 相似文献
24.
Farnaz Sepandar Maryam Daneshpazhooh Mahmoud Djalali Hamed Mohammadi Elham Yaghubi Zahra Fakhri Hajar Tavakoli Ehsan Ghaedi Ali Keshavarz Mahnaz Zarei Mohammad Amin Shahrbaf Narges Ghandi Mina Darand Mohamad Hassan Javanbakht 《Phytotherapy research : PTR》2020,34(4):859-866
Pemphigus vulgaris (PV) is a chronic autoimmune disorder with potentially fatal outcomes. The aim of this study was to investigate the effect of l ‐carnitine (LC) on secreted frizzled‐related protein‐5 (SFRP5), omentin, visfatin, and glycemic indices in PV patients under corticosteroid treatment. In this randomized, double‐blind, placebo‐controlled clinical trial, 52 patients with PV were divided randomly into two groups to receive 2 g of LC or a placebo for 8 weeks. Serum levels of SFRP5, omentin, visfatin, and also glycemic indices were evaluated at the baseline and end of the study. LC supplementation significantly decreased the serum level of visfatin (95% CI [?14.718, ?0.877], p = .05) and increased the serum levels of SFRP5 (95%CI [1.637, 11.380], p < .006) and omentin (95% CI [9.014, 65.286], p < .01). However, LC supplementation had no significant effects on the serum levels of glycemic factors such as insulin (95% CI [?1.125, 3.056], p = .426), fasting blood sugar (95% CI [?4.743, 3.642], p = .894), homeostatic model assessment of insulin resistance (95% CI [?0.305, 0.528], p = .729), and quantitative insulin‐sensitivity check index (95% CI [?0.016, ?0.010], p = .81). LC supplementation decreased visfatin serum level and increased omentin‐1 and SFRP5 serum levels in patients with PV. However, it has no significant effect on the serum levels of insulin and glycemic indices. 相似文献
25.
Katrice M. Karanfilian MD Monica N. Valentin MD Rajendra Kapila MD Chinmoy Bhate MD Mahnaz Fatahzadeh DMD MSD FRCP Edin Giuseppe Micali MD FRCP Edin Robert A. Schwartz MD MPH DSc FRCP 《International journal of dermatology》2020,59(10):1185-1190
Cervicofacial actinomycosis is an uncommon, chronic, suppurative, and granulomatous bacterial infection. It is often of dental origin and tends to mimic other dental infections, granulomatous disorders, and cancers. The initial diagnostic workup, predicated upon imaging and tissue biopsies, is frequently nonspecific. A definitive diagnosis is usually rendered only after surgical excision and histologic examination of the cervicofacial mass. We propose a classification of three stages: localized infection without sinus involvement, localized infection with sinus involvement, and disseminated infection, to facilitate recognition, diagnosis, and early aggressive treatment. Untreated infection may be life-threatening. Therapy may require long-term antibiotics; however, many cases may also necessitate complete surgical excision. 相似文献
26.
Snake modeling and distance transform approach to vascular centerline extraction and quantification 总被引:4,自引:0,他引:4
A new method for fully automated centerline extraction and quantification of microvascular structures in confocal microscopy (CM) images is presented. Our method uses the idea of active contour models as well as path planning and distance transforms for the three-dimensional centerline extraction of elongated objects such as vessels. The proposed approach is especially efficient for centerline extraction of complex branching structures. The method performance is validated in several CM images of both normal and stroked rat brains as well as simulated objects. The results confirm the efficiency of the proposed method in extracting the medial curve of vessels, which is essential for the computation of quantitative parameters. 相似文献
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BongKyoo Choi Per-Olof Östergren Catarina Canivet Mahnaz Moghadassi Sara Lindeberg Robert Karasek Sven-Olof Isacsson 《International archives of occupational and environmental health》2011,84(1):77-89