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991.
992.
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
993.
994.
Fatemeh Foroohimanjili Amir Mirzaie Seyed Mohammad Mehdi Hamdi Hassan Noorbazargan Mojtaba Hedayati Ch Aghigh Dolatabadi Hossein Rezaie Faezeh M. Bishak 《Journal of basic microbiology》2020,60(3):216-230
The aim of the present work was to investigate the antibacterial, antibiofilm, and antiquorum sensing activities of phytosynthesized silver nanoparticles (AgNPs) fabricated from Mespilus germanica extract against multidrug-resistant (MDR) Klebsiella pneumoniae strains. Fifty strains of K. pneumoniae were isolated from various clinical specimens. Biofilm-forming strains were identified using Congo red agar and polymerase chain reaction (PCR) techniques. Subsequently, the antibacterial activity of phytosynthesized AgNPs on MDR K. pneumoniae strains was investigated by broth microdilution assay and agar well-diffusion method. Finally (in the last step), the antibiofilm activity of phytosynthesized AgNPs was determined using microtiter plate assay and real-time PCR (RT-PCR) methods for the analysis of type 3 fimbriae (mrkA) and quorum-sensing system (luxS) gene expression. The results of this study showed that the phytosynthesized AgNPs had a spherical nanostructure with the mean size of 17.60 nm. The AgNPs exhibited dose-dependent antibacterial activity. The results of the microtiter plate and RT-PCR methods show that AgNPs inhibited the biofilm formation in MDR K. pneumoniae strains, and the expressions of mrkA and luxS genes were downregulated significantly in MDR strains after treatment with a subminimum inhibitory concentration of AgNPs. In conclusion, AgNPs effectively prevent the formation of biofilms and kill bacteria in established biofilms, which suggests that AgNPs might be a promising candidate for the prevention and treatment of biofilm-related infections caused by MDR K. pneumoniae strains. 相似文献
995.
Md. Akhtar-E Ekram Indrani Sarker Md. Sifat Rahi Md. Atikur Rahman Ananda K. Saha Md. Abu Reza 《Journal of basic microbiology》2020,60(5):390-399
Excessive use of pesticides in agricultural fields is a matter of great concern for living beings as well as the environment across the world, in particular, the third world countries. Therefore, there is an urgent need to find out an effective way to degrade these hazardous chemicals from the soil in an environment-friendly way. In the current project, a bacterial species were isolated through enrichment culture from carbofuran-supplemented rice-field soil and identified as a carbofuran degrader. The rate of carbofuran degradation by this bacterial species was evaluated using reverse-phase high-performance liquid chromatography (RP-HPLC), which confirmed the ability to utilize as a carbon source up to 4 µg/ml of 99% technical grade carbofuran. The morphological, physiological, biochemical characteristics and phylogenetic analysis of the 16S rRNA sequence showed that this strain belongs to the genus of Enterobacter sp. (sequence accession number LC368285 in DDBJ), and the optimum growth condition for the isolated strain was 37°C at pH 7.0. Moreover, an antibiotic sensitivity test showed that it was susceptible to azithromycin, penicillin, ceftazidime, ciprofloxacin, and gentamycin, and the minimal inhibitory concentration value of gentamycin was 400 μg/ml against the bacteria. It shows beyond doubt from the RP-HPLC quantification that the isolated bacterium has the ability to detoxify carbofuran (99% pure). Finally, the obtained results imply that the isolated strain of Enterobacter can be used as a potential and effective carbofuran degrader for bioremediation of contaminated sites through bioaugmentation. 相似文献
996.
El-Zayadi Ahmed A. Mohamed Sara A. Arafa Mohammad Mohammed Shereen M. Zayed Abdelhady Abdelhafez Mohamed S. Badawy Ahmed M. 《Immunologic research》2020,68(6):389-397
Immunologic Research - Many pro-inflammatory cytokines especially tumor necrotic factor alpha (TNFα), interleukin (IL)-1β, and IL-6 have crucial role in the pathogenesis of endometriosis.... 相似文献
997.
Mohammad Shah Faizan 《Journal of medical engineering & technology》2020,44(4):190-197
AbstractIn this study, a wearable device is developed as a mechanical treatment to suppress hand tremors in people with Parkinson's disease (PwPD). The biodynamic modelling of the human hand was done by considering the hand as a primary mass-spring-damper system. Dual passive vibration absorbers have been designed to match the frequencies of tremors. The performance assessment of the device was performed using the temporal response of hand tremors. The results showed that the device reduced the amplitude of the angular movement of the wrist by 57.25%. The device fabricated in the form of a bracelet was easy to wear by PwPD when needed. 相似文献
998.
Michal M. Andelman‐Gur Richard J Leventer Mohammad Hujirat Christos Ganos Keren Yosovich Nirit Carmi Dorit Lev Andreea Nissenkorn William B. Dobyns Kailash Bhatia Tally Lerman‐Sagie Lubov Blumkin 《American journal of medical genetics. Part A》2020,182(10):2207-2213
The clinical presentation of bilateral perisylvian polymicrogyria (PMG) is highly variable, including oromotor dysfunction, epilepsy, intellectual disability, and pyramidal signs. Extrapyramidal features are extremely rare. We present four apparently unrelated patients with a unique association of PMG with dystonia. The clinical, genetic, and radiologic features are described and possible mechanisms of dystonia are discussed. All patients were female and two were born to consanguineous families. All presented with early childhood onset dystonia. Other neurologic symptoms and signs classically seen in bilateral perisylvian PMG were observed, including oromotor dysfunction and speech abnormalities ranging from dysarthria to anarthria (4/4), pyramidal signs (3/4), hypotonia (3/4), postnatal microcephaly (1/4), and seizures (1/4). Neuroimaging showed a unique pattern of bilateral PMG with an infolded cortex originating primarily from the perisylvian region in three out of four patients. Whole exome sequencing was performed in two out of four patients and did not reveal pathogenic variants in known genes for cortical malformations or movement disorders. The dystonia seen in our patients is not described in bilateral PMG and suggests an underlying mechanism of impaired connectivity within the motor network or compromised cortical inhibition. The association of bilateral PMG with dystonia in our patients may represent a new neurogenetic disorder. 相似文献
999.
Sandra Donkervoort Payam Mohassel Lucia Laugwitz Maha S. Zaki Erik‐Jan Kamsteeg Reza Maroofian Katherine R. Chao Corien C. Verschuuren‐Bemelmans Veronka Horber Annemarie J. M. Fock Riley M. McCarty Minal S. Jain Victoria Biancavilla Grace McMacken Matthew Nalls Nicol C. Voermans Hasnaa M. Elbendary Molly Snyder Chunyu Cai Tanya J. Lehky Valentina Stanley Susan T. Iannaccone A. Reghan Foley Hanns Lochmüller Joseph Gleeson Henry Houlden Tobias B. Haack Rita Horvath Carsten G. Bönnemann 《American journal of medical genetics. Part A》2020,182(10):2272-2283
Synaptotagmins are integral synaptic vesicle membrane proteins that function as calcium sensors and regulate neurotransmitter release at the presynaptic nerve terminal. Synaptotagmin‐2 (SYT2), is the major isoform expressed at the neuromuscular junction. Recently, dominant missense variants in SYT2 have been reported as a rare cause of distal motor neuropathy and myasthenic syndrome, manifesting with stable or slowly progressive distal weakness of variable severity along with presynaptic NMJ impairment. These variants are thought to have a dominant‐negative effect on synaptic vesicle exocytosis, although the precise pathomechanism remains to be elucidated. Here we report seven patients of five families, with biallelic loss of function variants in SYT2, clinically manifesting with a remarkably consistent phenotype of severe congenital onset hypotonia and weakness, with variable degrees of respiratory involvement. Electrodiagnostic findings were consistent with a presynaptic congenital myasthenic syndrome (CMS) in some. Treatment with an acetylcholinesterase inhibitor pursued in three patients showed clinical improvement with increased strength and function. This series further establishes SYT2 as a CMS‐disease gene and expands its clinical and genetic spectrum to include recessive loss‐of‐function variants, manifesting as a severe congenital onset presynaptic CMS with potential treatment implications. 相似文献
1000.
Mostafa Ahmadi Mahbobeh Faramarzi Zahra Basirat Farzan Kheirkhah Mohammad Chehrazi Fatemeh Ashabi 《African health sciences》2020,20(3):1241
BackgroundPolycystic Ovarian Syndrome (PCOS) is one of the most common causes of infertility in women.ObjectiveThe current study investigated mental and personality disorders in infertile women with and without PCOS.MethodsThis case-control study evaluated 400 infertile women who referred to the Infertility Center in Babol city (North of Iran). Participants were categorized into the case group (201 PCOS) and the control group (199 without PCOS). All of the participants completed the Millon Clinical Multi-axial Inventory-III (MCMI-III).ResultsThe mean scores for clinical personality patterns were significantly higher for six personality disorders (schizoid, avoidant, antisocial, depressive, sadistic, and negativistic) and for three classes of severe personality disorder patterns (schizotypal, borderline, and paranoid) in infertile women with PCOS than in women without PCOS. The mean scores for eight clinical disorders (somatoform, manic disorder, dysthymia, alcohol-dependence, drug-dependence, post-trauma stress disorder, major depression, and delusion disorder) were also higher in infertile women with PCOS than in women without PCOS.ConclusionThe scores of many mental and personality disorders are higher in infertile women with PCOS than in women without PCOS. Thus, clinicians should prioritize recognizing and treating psychological problems of infertile women with PCOS. 相似文献