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目的探讨两例父源性17q12微缺失综合征胎儿的产前诊断和遗传咨询。方法一名孕妇的两例胎儿的孕中晚期超声检查均提示肾脏异常和羊水过多,应用单核苷酸多态性分析(single nucleotide polymorphism array,SNP-array)分别对第1胎的脐血样本和第2胎的羊水样本进行产前诊断。发现第1胎染色体17q12微缺失后,父母进行外周血SNP-array检测以确定遗传来源。结合双亲临床病史,其父亲进行泌尿系统相关的565个基因的高通量测序,以排除泌尿系统及生殖器官先天性结构畸形相关的已知致病变异或疑似致病变异可能。结果该家系两例胎儿SNP-array结果均为arr[hg19]17q12(34822465~36243365)×1,大小约1.4 Mb,为17q12微缺失综合征,遗传自父亲。胎儿父亲未发现泌尿系统相关的致病或疑似致病变异。结论父源性17q12微缺失可能为两例胎儿超声肾脏异常和羊水过多的遗传学病因。产前SNP-array检测可明确诊断,为该家系的遗传咨询及产前诊断提供依据。  相似文献   
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目的:探讨弥漫大B细胞淋巴瘤(DLBCL)患者外周血中白细胞介素6(IL-6)、白细胞介素8(IL-8)和白细胞介素10(IL-10)的表达及其临床意义。方法:回顾性分析2018年3月至2021年3月厦门大学附属第一医院78例初治DLBCL患者的临床资料,选取同期58名健康体检者作为健康对照。采用流式微球捕获芯片技术(CBA)检测受试者外周血中IL-6、IL-8和IL-10表达水平,并分析DLBCL患者这些指标与临床特征、疾病分期和预后的关系。结果:DLBCL组IL-6、IL-8和IL-10表达水平均高于健康对照组[(171.81±70.91)pg/ml比(2.71±0.28)pg/ml,(47.95±13.04)pg/ml比(3.69±0.47)pg/ml,(38.02±10.35)pg/ml比(1.77±0.23)pg/ml],差异均有统计学意义( t值分别为2.38、3.39、3.50,均 P<0.05)。DLBCL患者中,骨髓侵犯、国际预后指数(IPI)评分3~5分及临床分期Ⅲ~Ⅳ期患者的IL-6、IL-8和IL-10水平均高于骨髓未侵犯、IPI评分1~2分及临床分期Ⅰ~Ⅱ期患者(均 P<0.05)。DLBCL患者外周血中IL-6与IL-8、IL-6与IL-10、IL-8与IL-10表达水平均相关( r2值分别为0.93、0.89、0.89,均 P<0.05)。IL-6、IL-8、IL-10均高表达的患者中,临床分期为Ⅲ~Ⅳ期、6个疗程后未缓解患者比例均高于IL-6、IL-8、IL-10单项及两项高表达患者,差异均有统计学意义(均 P<0.05)。 结论:DLBCL患者外周血清中IL-6、IL-8和IL-10表达水平具有较高的相关性,三者表达水平升高预示DLBCL患者疾病分期较晚、预后较差。  相似文献   
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Melanoma ex blue nevus (MEBN) is a rare, aggressive, and potentially lethal neoplasm. Distinguishing MEBN from an atypical cellular blue nevus can be very challenging. We report a diagnostically difficult case of MEBN with lymph node metastases, in which single nucleotide polymorphism array and fluorescence in situ hybridization were used to arrive at the correct diagnosis. It was also analyzed by the recently‐introduced proprietary 23‐gene expression signature test. To the best of our knowledge, this is the second reported case of MEBN analyzed by the 23‐gene expression signature, which provided a false‐negative result. More studies are needed to assess the sensitivity and specificity of this test in various melanocytic proliferations.  相似文献   
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PurposeTo investigate if high-frequency irreversible electroporation (H-FIRE) treatments can be delivered at higher voltages and with greater energy delivery rates than currently implemented in clinical irreversible electroporation protocols.Materials and MethodsTreatments using 3,000 V and 5,000 V were administered to mechanically perfused ex vivo porcine liver via a single applicator and grounding pad (A+GP) as well as a 4-applicator array (4AA). Integrated energized times (IET) 0.01–0.08 seconds and energy delivery rates 25–300 μs/s were investigated. Organs were preserved at 4°C for 10–15 hours before sectioning and gross analysis using a metabolic stain to identify the size and shape of ablation zones.ResultsA+GP ablations measured between 1.6 cm and 2.2 cm, which did not increase when IET was increased from 0.02 seconds to 0.08 seconds (P > .055; range, 1.9–2.1 cm). Changes in tissue color and texture consistent with thermal damage were observed for treatments with energy delivery rates 50–300 μs/s, but not for treatments delivered at 25 μs/s. Use of the 4AA with a 3-cm applicator spacing resulted in ablations measuring 4.4–4.9 cm with energy delivery times of 7–80 minutes.ConclusionsH-FIRE treatments can rapidly and reproducibly create 2-cm ablations using an A+GP configuration. Treatments without thermal injury were produced at the expense of extended treatment times. More rapid treatments resulted in ablations with varying degrees of thermal injury within the H-FIRE ablation zone. Production of 4-cm ablations is possible using a 4AA.  相似文献   
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The primary objective of this study was to analyse Tetranectin (TN) expression in tumour tissues and TN serum concentration in 758 women with epithelial ovarian tumours. The second was to evaluate, whether TN tissue expression levels correlate with clinico‐pathological parameters and prognosis of the disease. Using tissue arrays we analysed the expression levels in tissues from 166 women with borderline ovarian tumours (BOTs) and 592 women with ovarian cancer (OC). A panel of three antibodies was used for immunohistochemistry: a polyclonal and two monoclonal antibodies. Serum TN was measured using the polyclonal antibody A‐371. Univariate survival analyses stratified for chemotherapy showed that positive tissue TN as demonstrated by the polyclonal antibody indicated a significantly longer overall survival (OS) (p = 0.0001) as well as cancer specific survival (CSS) (p < 0.0001). High serum TN was likewise found to imply longer OS (p < 0.0001) and CSS (p < 0.0001), whereas tissue staining with the two monoclonal antibodies failed to demonstrate any significant correlation with either survival type. Univariate Kaplan–Meier survival analysis performed on all OC cases showed a significantly longer OS (p = 0.0009) and CSS (p = 0.0006) for women with TN positive tumour tissue and in women with high serum TN levels (p < 0.0001 for both). However, in the multivariate Cox regression analysis, only serum TN was found to be an independent prognostic factor for OS (p = 0.01) and not for CSS (p = 0.08). In conclusion, our results predict that a positive TN expression of both tumour tissue and serum points to a more favourable outcome for OC patients.  相似文献   
9.
《Brain stimulation》2020,13(1):20-34
BackgroundPotentiation of synaptic activity in spinal networks is reflected in the magnitude of modulation of motor responses evoked by spinal and cortical input. After spinal cord injury, motor evoked responses can be facilitated by pairing cortical and peripheral nerve stimuli.ObjectiveTo facilitate synaptic potentiation of cortico-spinal input with epidural electrical stimulation, we designed a novel neuromodulation method called dynamic stimulation (DS), using patterns derived from hind limb EMG signal during stepping.MethodsDS was applied dorsally to the lumbar enlargement through a high-density epidural array composed of independent platinum-based micro-electrodes.ResultsIn fully anesthetized intact adult rats, at the interface array/spinal cord, the temporal and spatial features of DS neuromodulation affected the entire lumbosacral network, particularly the most rostral and caudal segments covered by the array. DS induced a transient (at least 1 min) increase in spinal cord excitability and, compared to tonic stimulation, generated a more robust potentiation of the motor output evoked by single pulses applied to the spinal cord. When sub-threshold pulses were selectively applied to a cortical motor area, EMG responses from the contralateral leg were facilitated by the delivery of DS to the lumbosacral cord. Finally, based on motor-evoked responses, DS was linked to a greater amplitude of motor output shortly after a calibrated spinal cord contusion.ConclusionCompared to traditional tonic waveforms, DS amplifies both spinal and cortico-spinal input aimed at spinal networks, thus significantly increasing the potential and accelerating the rate of functional recovery after a severe spinal lesion.  相似文献   
10.
《Brain stimulation》2020,13(6):1668-1677
BackgroundEndovascular delivery of current using ‘stentrodes’ – electrode bearing stents – constitutes a potential alternative to conventional deep brain stimulation (DBS). The precise neuroanatomical relationships between DBS targets and the vascular system, however, are poorly characterized to date.ObjectiveTo establish the relationships between cerebrovascular system and DBS targets and investigate the feasibility of endovascular stimulation as an alternative to DBS.MethodsNeuroanatomical targets as employed during deep brain stimulation (anterior limb of the internal capsule, dentatorubrothalamic tract, fornix, globus pallidus pars interna, medial forebrain bundle, nucleus accumbens, pedunculopontine nucleus, subcallosal cingulate cortex, subthalamic nucleus, and ventral intermediate nucleus) were superimposed onto probabilistic vascular atlases obtained from 42 healthy individuals. Euclidian distances between targets and associated vessels were measured. To determine the electrical currents necessary to encapsulate the predefined neurosurgical targets and identify potentially side-effect inducing substrates, a preliminary volume of tissue activated (VTA) analysis was performed.ResultsSix out of ten DBS targets were deemed suitable for endovascular stimulation: medial forebrain bundle (vascular site: P1 segment of posterior cerebral artery), nucleus accumbens (vascular site: A1 segment of anterior cerebral artery), dentatorubrothalamic tract (vascular site: s2 segment of superior cerebellar artery), fornix (vascular site: internal cerebral vein), pedunculopontine nucleus (vascular site: lateral mesencephalic vein), and subcallosal cingulate cortex (vascular site: A2 segment of anterior cerebral artery). While VTAs effectively encapsulated mfb and NA at current thresholds of 3.5 V and 4.5 V respectively, incremental amplitude increases were required to effectively cover fornix, PPN and SCC target (mean voltage: 8.2 ± 4.8 V, range: 3.0–17.0 V). The side-effect profile associated with endovascular stimulation seems to be comparable to conventional lead implantation. Tailoring of targets towards vascular sites, however, may allow to reduce adverse effects, while maintaining the efficacy of neural entrainment within the target tissue.ConclusionsWhile several challenges remain at present, endovascular stimulation of select DBS targets seems feasible offering novel and exciting opportunities in the neuromodulation armamentarium.  相似文献   
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