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1.
《Clinical breast cancer》2022,22(6):507-514
Breast cancer (BC) is a highly metastatic, pathological cancer that significantly affects women worldwide. The mortality rate of BC is related to its heterogeneity, aggressive phenotype, and metastasis. Recent studies have highlighted that the tumor microenvironment (TME) is critical for the interplay between metastasis mediators in BC. BC stem cells, tumor-derived exosomes, circulatory tumor cells (CTCs), and signaling pathways dynamically remodel the TME and promote metastasis. This review examines the cellular and molecular mechanisms governing the epithelial to mesenchymal transition (EMT) that facilitate metastasis. This review also discusses the role of cancer stem cells (CSCs), tumor-derived exosomes, and CTs in promoting BC metastasis. Furthermore, the review emphasizes major signaling pathways that mediate metastasis in BC. Finally, the interplay among CSCs, exosomes, and CTCs in mediating metastasis have been highlighted. Therefore, understanding the molecular cues that mediate the association of CSCs, exosomes, and CTCs in TME helps to optimize systemic therapy to target metastatic BC.  相似文献   
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ObjectiveTo compare corticospinal excitability and transcallosal inhibition between contralesional primary motor cortex (M1) and ipsilesional M1. We also investigated the correlation between transcallosal inhibition and upper extremity motor behavior.Materials and methods19 individuals with unilateral ischemic subacute stroke who had severe upper extremity impairment participated in this study. Corticospinal excitability was assessed by measuring the resting motor threshold, active motor threshold and motor evoked potential amplitude. Transcallosal inhibition was investigated by measuring the duration and depth of the ipsilateral silent period (ISP). The data from the two hemispheres were compared and the relationships of transcallosal inhibition with upper extremity motor impairment, grip strength and pinch strength were analyzed.ResultsResting motor threshold (p = 0.001) and active motor threshold (p = 0.001) were lower and motor evoked potential amplitude was higher (p = 0.001) in the contralesional M1 compared to the ipsilesional M1. However, there were no differences between the two M1s in ISP duration (p = 0.297) or ISP depth (p =0. 229). Transcallosal inhibition from the contralesional M1 was positively associated with motor impairment (ISP duration, p = 0.003; ISP depth, p = 0.017) and grip strength (ISP duration, p = 0.016; ISP depth, p = 0.045).ConclusionsSymmetric transcallosal inhibition between hemispheres and positive association of transcallosal inhibition from contralesional M1 with upper extremity motor behavior indicate that recruitment of contralesional M1 may be necessary for recovery in patients with severe upper extremity impairment after subacute ischemic stroke.  相似文献   
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Phelan-McDermid syndrome (PMS) is a rare neurodevelopmental disorder caused by rearrangements on chromosome 22q13.3 or sequence variants in SHANK3. Individuals with PMS caused by a 22q terminal deletion and a ring chromosome are at increased risk for Neurofibromatosis type 2 (NF2). However, the prevalence of NF2 in individuals with PMS and a r (22) is unknown.Individuals with PMS and a r (22) chromosome evaluated at the Greenwood Genetic Center (GGC) or by international collaborators, or identified through the PMS International Registry (PMSIR) were contacted and participated in a clinical questionnaire. Forty-four families completed the questionnaire and consented for the study. Of the individuals with a r (22), 7 (16%) carried a diagnosis of NF2. The average age of diagnosis of r (22) was 18 years old in individuals with NF2 and three years old in individuals without NF2 (p-value <0.001). Clinical findings were similar among all individuals in our sample with the exception of hearing loss, present in 57% of individuals with NF2 and 8% of individuals without NF2 (p-value <0.01).This is the largest clinical report of individuals with PMS and a r (22) chromosome. We show a diagnosis of NF2 in individuals with r (22) is not uncommon and may be under ascertained. Moreover, the presentation of NF2 in this cohort is variable and lifelong routine screening for features of NF2 in this population should be considered.  相似文献   
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BackgroundWith the number of primary total hip arthroplasty (THA), the amount of revision THA (R-THA) increases. R-THA is a complex procedure requiring special instruments, implants, and surgical skills. Therefore it is likely that hospitals performing a higher number of R-THAs have more experience with this type of surgery and therefore fewer complications. The purpose of this study was to evaluate the relationship between hospital volume and risk of postoperative complications following R-THA.MethodsUsing nationwide healthcare insurance data for inpatient hospital treatment, 17,773 aseptic R-THAs in 16,376 patients treated between January 2014 and December 2016 were included. Outcomes were 90-day mortality, 1-year revision procedures, and in-house adverse events. The effect of hospital volume on outcome was analyzed by means of multivariate logistic regression. Adjusted odds ratios (ORs) and 95% confidence intervals (CIs) were calculated.ResultsHospital volume had a significant effect on 90-day mortality (≤12 cases per year: OR 2.13, CI 1.53-2.96; 13-24: OR 1.79, CI 1.29-2.50; 25-52: OR 1.53, CI 1.11-2.10; ≥53: reference) and 1-year revision procedures (≤12: OR 1.26, CI 1.09-1.47; 13-24: OR 1.18, CI 1.02-1.37; 25-52: OR 1.03, CI 0.90-1.19; ≥53: reference). There was no significant effect on risk-adjusted major in-house adverse events.ConclusionWe found evidence of higher risk for revision surgery and mortality in hospitals with fewer than 25 and 53 R-THA per year, respectively. To improve patient care, complex elective procedures like R-THA which require experience and a specific logistic background should be performed in specialized centers.  相似文献   
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ObjectiveTo investigate the potential role of US in the detection of ILD in a cohort of patients with RA.MethodsPatients with diagnosis of RA were consecutively enrolled. All patients underwent pulmonary examination, laboratory data, DLCO measure, chest HRCT and radiographs, and US examination. A healthy group was included as control group. US was performed according the 14-intercostal space scanning protocol using the following semiquantitative scale [0 = normal (≤ 5 B-lines); 1 = slight (≥ 6 and ≤ 15 B-lines); 2 = moderate, (≤ 16 and ≥ 30 B-lines); 3 = severe (≥ 30 B-lines)].ResultsA total of 74 RA patients and 74 healthy controls were included. Thirty of 74 patients (40.5%) showed US signs of ILD with respect to the healthy controls (3 subjects, 4.1%) (P < 0.001); whereas HRCT showed ILD in 27 (36.4%) of 74 patients. Among the 30 patients that showed US findings of ILD, 17 (56.6%) were asymptomatic from respiratory view-point. The sensitivity and specificity of US were 92% and 89% respectively. A positive correlation between US and HRCT findings were found (P < 0.001) whereas no correlation was found with chest radiographs and DLCO findings. Positive association between US findings and DAS28-ESR, anti-CCP and RF (P < 0.01 for each respectively) was found. Feasibility, represented by the mean time spent to perform the pulmonary US assessment was 7.8 minutes (± SD 1.2, range 6 to 10 minutes).ConclusionsOur results support the potential of US in detect accurately ILD in patients with RA and provide a rationale to consider it as a friendly screening tool to be implemented in early phases of the disease.  相似文献   
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This paper is the first in a series providing updated guidance on the definition, evaluation and management of people with a Cystic Fibrosis Transmembrane conductance Regulator (CFTR)-Related Disorder (CFTR-RD). The need for this update relates to more precise characterisation of CFTR gene variants and improved assessment of CFTR protein dysfunction. The exercise is co-ordinated by the European CF Society Standards of Care Committee and Diagnostic Network Working Group and involves stakeholder engagement. This first paper was produced by a core group using an extensive literature review and papers graded for their quality. Subsequent wider stakeholder agreement was achieved.The definition of a CFTR-RD remains “a clinical condition with evidence of CFTR protein dysfunction that does not fulfil the diagnostic criteria for CF”. Clearer guidance on CFTR dysfunction and relevant CFTR variants will be provided. Thresholds for clinical presentations are presented and the paradigm that pathobiological processes may be evident in more than one organ is agreed. In this paper we reflect on the early patient journey, highlighting that CF specialists as well as other relevant specialists should be involved in the care of people with a CFTR-RD.  相似文献   
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目的研究mi R-9在膀胱癌中对CBX7基因表达的调控作用及机制。方法应用荧光定量PCR方法检测膀胱癌及癌旁组织中mi R-9及CBX7基因的表达。培养膀胱癌T24细胞,转染mi R-9的前体pre-mi R-9,Western blot检测CBX7蛋白的表达。荧光素酶报告基因表达分析明确mi R-9与CBX7基因3'非翻译区(3'UTR)的结合。结果 mi R-9在膀胱癌组织中的表达较癌旁组织呈现显著的上调,而CBX7的表达则下调明显,二者的表达呈显著负相关。在转染后膀胱癌T24细胞中,pre-mi R-9能够分别下调T24细胞中CBX7蛋白的表达。荧光素酶报告基因表达分析明确mi R-9能够与CBX7基因的3'UTR结合并负性调节其表达。结论 mi R-9与CBX7基因的表达改变与膀胱癌相关,mi R-9能够在膀胱癌细胞中靶向负性调节CBX7基因的表达。  相似文献   
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目的:明确转染BMP-Ⅱ型突变受体对Tca8113舌癌细胞的作用,以进一步探讨BMPs对口腔上皮恶变的作用机制。方法:用FuGENll6(Transfection Reagent Kit)真核转染试剂盒将携带BMP-Ⅱ型突变受体cDNA的真核表达载体转染Tca8113细胞(命名为Tca8113ZR细胞);然后对Tca8113ZR和Tca8113细胞分别进行生长曲线、MTT检测,FCM分析,BrdU标记检测细胞的增殖活性及DNA合成;以观察转染前后舌癌细胞生物学性状的变化。结果:Tca8113ZR细胞和Tca8113细胞相比,形态未见明显变化,但是细胞的增殖活力明显下降。结论:BMPs信号表达水平的改变在口腔上皮组织的恶变过程中起着十分重要的调控作用。  相似文献   
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