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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   
993.
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   
994.
In the last decade, there has been a tremendous development of technologies focused on analysing various molecular attributes in single cells, with an ever-increasing number of parameters becoming available at the DNA, RNA and protein levels. Much of this progress has involved cells in suspension, but also in situ analysis of tissues has taken great leaps. Paralleling the development in the laboratory, and because of increasing complexity, the analysis of single-cell data is also constantly being updated with new algorithms and analysis platforms. Our immune system shares this complexity, and immunologists have therefore been in the forefront of this technological development. These technologies clearly open new avenues for immunology research, maybe particularly within autoimmunity where the interaction between the faulty immune system and the thymus or the target organ is important. However, the technologies currently available can seem overwhelming and daunting. The aim of this review is to remedy this by giving a balanced overview of the prospects of using single-cell analysis in basal and clinical autoimmunity research, with an emphasis on endocrine autoimmunity.  相似文献   
995.
Abstract

In 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   
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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   
997.
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   
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