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691.
692.
Parisa Sinai Chau Nguyen John D. Schatzle Christoph Wülfing 《Proceedings of the National Academy of Sciences of the United States of America》2010,107(26):11912-11917
Cytolytic effectors polarize toward target cells for effective killing and IFN-γ secretion. The spatiotemporal features of this polarization and their importance for cytolysis have not been resolved. In cytotoxic T cells and natural killer (NK) cells, transient polarization was consistently associated with effective killing. Polarization was regulated by Cdc42, a small Rho family GTPase universally critical for cytoskeletal dynamics. Transient accumulation of active Cdc42 at the cytolytic effector/target cell interface and focus of such accumulation on the interface center were closely related to cytolysis. Surprisingly, however, the intensity of Cdc42 activation was not. We interfered with Cdc42 activation in NK cells such that sustained polarization in long lasting nonkilling cell couples was selectively blocked. Thus the proportion of the NK cell population displaying transient polarization was increased. As a consequence, cytolytic responder frequency and IFN-γ production were enhanced upon such interference with Cdc42 activation. These data support the notion that transience in polarization is critical for cytolytic effector function, likely by preventing cytolytic effectors from becoming trapped in nonproductive target cell interactions. 相似文献
693.
Mehran Hiradfar Nona Zabolinejad Reza Shojaeian Parisa Saeedi Marjan Joodi Reza Nazarzadeh Hamid Farhangi Mohammad Abbasi Tashnizi Seyed Ali Alamdaran 《Pediatric surgery international》2012,28(11):1141-1145
Clear cell sarcoma of the kidney (CCSK) is an uncommon neoplasm that accounts for almost 3?% of pediatric renal tumors. Cavoatrial tumor thrombosis is very rare and because of poor response to chemotherapy, invasive surgical interventions such as open heart surgery may be indicated. A 6-year-old girl with CCSK of right kidney was treated with neoadjuvant chemotherapy. According to poor chemosensitivity, surgical intervention was planned. Right atriotomy was done, but intra-atrial part of tumor was very firm and unsuctionable; so the procedure was completed by laparotomy and en bloc resection of tumoral kidney and its cavoatrial extension through a limited venotomy on inferior vena cava. Although radical resection of CCSK with intracaval involvement should be considered as a multidisciplinary approach and intensive care and supports should be provided, atriocaval tumor in growth in CCSK is firm, non friable and non-adherent, and tumor en bloc resection may be possible through a limited venotomy via primary abdominal approach. 相似文献
694.
Emami-Naeini P Nejat F Rahbar Z Kajbafzadeh A El Khashab M 《Journal of pediatric urology》2012,8(2):181-186
ObjectiveTo evaluate urologic manifestations of sacral agenesis (SA) and their association with bony defects.MethodsUrological manifestations of SA were investigated in 50 patients referred to the urology or neurosurgery department. Urologenital signs and symptoms were assessed and a complete history of previous surgical procedures was attained. Plain lumbosacral radiography, abdominal/pelvic ultrasound, voiding cystourethrogram and urodynamic study were evaluated if available.ResultsThe most common urologic complaints were urinary incontinence and/or constant dribbling, seen in 30 (85%) of 35 children aged 4 years and over. Recurrent urinary tract infection, the second most common, was seen in 37 (74%). Vesicoureteral reflux was identified in 32 (65.3%) patients, 19 (59.3%) were found to have high maximal voiding pressures and post-voiding residual urine was notable in 42 (85.7%). Abnormal urodynamic parameters were found to be consistent with a neurogenic bladder in all patients. Cases were divided into upper motor lesions (in 34) and lower motor disorders (in 15). There was no statistically significant correlation for any GU finding with type of bony aplasia or motor neuron lesion (P = 0.338).ConclusionVoiding impairment and VUR together with recurrent UTI, especially in children with associated renal anomalies, contribute to renal damage. Urinary incontinence with associated social problems frequently occurs in patients with SA. Considering the devastating consequences of this disease in the urinary tract, timely diagnosis, thorough evaluation and appropriate intervention are essential. 相似文献
695.
Elisabeth Conradt Nila Shakiba Brendan Ostlund Sarah Terrell Parisa Kaliush Julie H. Shakib Sheila E. Crowell 《Developmental psychobiology》2020,62(6):758-767
Hair cortisol concentrations measured during pregnancy have emerged as a novel biomarker for prenatal stress exposure. However, associations between prenatal stress and distress, broadly defined, and hair cortisol concentrations during pregnancy are inconsistent. We examined relations among hair cortisol concentrations during the third trimester with (a) emotion dysregulation and (b) detailed measures of maternal prenatal stress. We also examined the predictive validity of maternal hair cortisol during pregnancy for adverse newborn health outcomes. Cortisol concentrations were derived from 6 cm of hair during the third trimester of pregnancy. Mothers reported on their emotion dysregulation and stress at this time. A standardized newborn neurobehavioral exam was conducted shortly after birth and newborn birth weight and gestational age were assessed from medical records. All hypotheses were preregistered on the Open Science Framework (osf.io/279ng). High levels of emotion dysregulation, but not stress, were predictive of high hair cortisol concentrations. Maternal prenatal BMI mediated the relation between maternal prenatal emotion dysregulation and hair cortisol concentrations. There was no association between hair cortisol and infant birth outcomes. This research supports the notion that transdiagnostic markers of psychopathology are important correlates of hair cortisol concentrations during pregnancy. 相似文献
696.
The Toll-like receptor adaptor proteins MyD88 and Mal/TIRAP contribute to the inflammatory and destructive processes in a human model of rheumatoid arthritis 总被引:5,自引:0,他引:5 下载免费PDF全文
Sacre SM Andreakos E Kiriakidis S Amjadi P Lundberg A Giddins G Feldmann M Brennan F Foxwell BM 《The American journal of pathology》2007,170(2):518-525
The widespread distribution of Toll-like receptors (TLRs) and their ligands raises the question whether they contribute to the production of inflammatory and tissue destructive molecules in rheumatoid arthritis (RA). We examined the expression and function of TLR2 and TLR4 and their downstream signaling adaptors MyD88 and Mal/TIRAP in synovial membrane cultures from RA tissue. Both TLR2 and TLR4 were detected by flow cytometry, and stimulation with TLR2 and TLR4 ligands augmented the spontaneous production of tumor necrosis factor-alpha, interleukin (IL)-6, and IL-8, indicating that TLR2 and TLR4 are functional in these cultures. In addition, overexpression of dominant-negative forms of MyD88 and Mal/TIRAP significantly down-regulated the spontaneous production of cytokines tumor necrosis factor-alpha, IL-6, and vascular endothelial growth factor, and enzymes MMP-1, MMP-2, MMP-3, and MMP-13 in RA synovial membrane cell cultures. Because TLR2 and TLR4 require both MyD88 and Mal/TIRAP for signaling, this study suggests that TLR function may regulate the expression of these factors in the RA synovium. Conditioned media from synovial membrane cell cultures stimulated human macrophages in a MyD88- and Mal-dependent manner, suggesting the release of a TLR ligand(s) from these cells. Thus, TLRs not only protect against infection but may also promote the inflammatory and destructive process in RA. 相似文献
697.
Identification of three novel TECTA mutations in Iranian families with autosomal recessive nonsyndromic hearing impairment at the DFNB21 locus 总被引:1,自引:0,他引:1
Meyer NC Alasti F Nishimura CJ Imanirad P Kahrizi K Riazalhosseini Y Malekpour M Kochakian N Jamali P Van Camp G Smith RJ Najmabadi H 《American journal of medical genetics. Part A》2007,(14):1623-1629
Forty-five consanguineous Iranian families segregating autosomal recessive nonsyndromic hearing loss (ARNSHL) and negative for mutations at the DFNB1 locus were screened for allele segregation consistent with homozygosity by descent (HBD) at the DFNB21 locus. In three families demonstrating HBD at this locus, mutation screening of TECTA led to the identification of three novel homozygous mutations: one frameshift mutation (266delT), a transversion of a cytosine to an adenine (5,211C > A) leading to a stop codon, and a 9.6 kb deletion removing exon 10. In total, six mutations in TECTA have now been described in families segregating ARNSHL. All of these mutations are inactivating and produce a similar phenotype that is characterized by moderate-to-severe hearing loss across frequencies with a mid frequency dip. The truncating nature of these mutations is consistent with loss-of-function, and therefore the existing TECTA knockout mouse mutant represents a good model in which to study DFNB21-related deafness. 相似文献
698.
Aghahosseini M Aleyassin A Khodaverdi S Esfahani F Mohammadbeigi R Movahedi S Kord Valeshabad A Mahdavi A Fallahi P Shabani P Rezaeeian Z Khodaverdi M 《Journal of assisted reproduction and genetics》2011,28(9):785-790
Purpose
This study was designed to evaluate the effects of adding Estradiol (E2) supplementation to progesterone (P) on improvement of pregnancy outcomes in poor responder patients who underwent in vitro fertilization (IVF).Methods
In a prospective randomized clinical trial, 118 poor responder patients, older than 38 years without contraindications of estradiol consumption from Infertility clinic of a university hospital were randomly divided (by computerized software) into two groups. Control group (59 patients) received only P and intervention group (59 patients) received P and E2 (4 mg/d). Supplementation was done with 4 mg E2 in the luteal phase. Fertilization rate, implantation rate, biochemical and clinical pregnancy rates, abortion rate, ongoing pregnancy, multiple pregnancy and ectopic pregnancy rates were documented for those who completed the study protocol in each group (per protocol analysis) and compared between groups.Result
Fifty five patients in control group and 53 patients in intervention group successfully completed the study protocol. Treatment outcomes were not significantly different between two groups.Conclusion
For poor responder women who underwent IVF, addition of E2 to P supplementation could not significantly improve pregnancy outcomes. 相似文献699.
A novel upstream enhancer of FOXP3, sensitive to methylation‐induced silencing,exhibits dysregulated methylation in rheumatoid arthritis Treg cells 下载免费PDF全文
700.
Tajik N Shah-hosseini A Mohammadi A Jafari M Nasiri M Radjabzadeh MF Farnia P Jalali A 《Tissue antigens》2012,79(2):90-96
Natural killer (NK) cells have distinctive functional capacities that are likely to contribute both to innate and adaptive immunity to Mycobacterium tuberculosis. Killer cell immunoglobulin-like receptors (KIR) and their ligands, i.e. human leukocyte antigen (HLA) class I molecules contribute partly in regulation of NK cell activity. In this study, the impact of compound KIR/HLA genotype on susceptibility to pulmonary tuberculosis (TB) has been evaluated in Iranian individuals. A total of 107 TB patients and 100 matched healthy controls were genotyped for 17 KIR genes and their three major HLA class I ligand groups (-C1, -C2 and -Bw4: -B Bw4(Ile80) , -B Bw4(Thr80) and -A Bw4) by a polymerase chain reaction-sequence-specific primers assay. Various analyses including distribution of KIR and HLA ligand genes and genotypes, frequency of inhibitory and activating KIR+HLA combinations and compound genotype status regarding balance of inhibitory and activating components showed no significant difference between patient and control groups. These findings may suggest that compound KIR/HLA genotype has no major impact on limiting Mycobacterium tuberculosis infection. 相似文献