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1.
Histiocytoses, including Langerhans cell histiocytosis (LCH), juvenile or adult xanthogranuloma (AXG) and Rosai–Dorfman disease (RDD), are rare disorders characterized by the proliferation of cells derived from monocyte/macrophage lineages. A few cases of LCH coexisting with xanthogranuloma or RDD have been reported. The etiology of these diseases remains unclear. However, oncogenic BRAFV600E mutations have been identified in LCH. Here, we report the case of a 26‐year‐old Japanese man with a 3‐month history of a solitary occipital nodule. No abnormality was detected in his other organs, and a total resection of the nodule was performed. Histopathological examination revealed the coexistence of LCH and AXG with prominent emperipolesis characteristic of RDD. Immunohistochemistry showed that most of the large histiocytes were positive for CD68, weakly positive or negative for S100, and negative for CD207 and CD1a, supporting the diagnosis of AXG. The tumor cells with emperipolesis did not show S100‐positive findings characteristic of RDD. The focally aggregated oval histiocytic cells were positive for CD1a, CD207, CD68 and S100, and were compatible with the immunophenotype of LCH cells. In addition, these cells were positive for BRAFV600E mutation. The tumor cells in our patient exhibited a cellular morphology characteristic of multiple histiocytoses in a solitary cutaneous nodule, which may imply an etiological association among LCH, AXG and RDD. To our knowledge, this is the first report of a BRAFV600E mutation‐positive case of LCH coexisting with AXG. Because patients with BRAFV600E mutation have higher risks of multisystemic LCH and recurrence, we should carefully follow up the patient.  相似文献   
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Introduction: Tumor biology, as well as completeness of surgical resection, are two important prognostic factors when treating retroperitoneal sarcoma (RPS). A frontline extended surgical approach is associated with improved local control and possibly improved survival. However, this approach has to be tailored to each histological subtype, as the patterns of growth and recurrence risks vary significantly among them.

Areas covered: We provide a review of the literature in RPS, describing the behavior of each of the five main histologic subtypes: well-differentiated liposarcoma (WDLPS), dedifferentiated liposarcoma (DDLPS), leiomyosarcoma (LMS), solitary fibrous tumor (SFT) and malignant peripheral nerve sheath tumor (MPNST). The prognostic factors relevant to oncologic outcomes of RPS, the role of margins and the importance of local control are discussed. Finally, a histologic specific surgical approach to RPS is provided in detail.

Expert opinion: While tumor-related factors are paramount, the only intervenable predictive factor is extent and quality of surgery. The extended surgical approach has been advocated for previously and again we describe it in more detail, tailored specifically to the tumor subtype. The aim of this approach is to maximize the possibility of achieving a complete resection through a standardized approach based on histologic behavior and site of origin.  相似文献   

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目的:探讨眼眶孤立性纤维瘤(SFT)的彩色多普勒超声及磁共振成像(MRI)特点。

方法:回顾性病例研究。收集2013-04/2018-08天津医科大学眼科医院收治的12例眼眶SFT患者的临床资料,均行彩色多普勒超声和MRI平扫、增强及动态增强检查,分析其临床影像学特点。

结果:纳入的12例患者中男7例,女5例,病程3mo~20a(平均3.2±5.2a),6例为首次发病,6例为复发病例; 均为单眼发病,其中左眶8例,右眶4例。肿瘤位于眼球后肌锥间隙内5例,肌锥间隙外3例,跨肌锥间隙内、外4例; 肿瘤形状呈卵形9例,不规则形3例,边界均清晰。超声表现为低回声10例,不均匀回声2例; 12例彩色多普勒血流显像(CDFI)均可见血流信号,阻力指数(RI)平均值0.70,PW均测得动脉频谱。MRI表现在T1WI均呈等信号; T2WI呈低信号 5例,等信号3例,中高信号4例,内部信号均匀9例,不均匀3例; 增强后12例均呈显著强化,10例均匀强化,2例不均匀强化。动态增强扫描的时间-信号强度曲线(TIC)7例为速升平台型,5例为速升速降型。

结论:眼眶SFT在彩超显示低回声、富血供的实体瘤,MRI提示T1WI呈等信号,T2WI信号混杂,增强后显著强化,动态增强TIC曲线以速升型为主的特征性表现对诊断具有重要意义。  相似文献   

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目的:探讨微创经皮肾镜取石术(MPCNL)联合输尿管软镜碎石术(FURSL)治疗孤立肾鹿角形结石的临床疗效,并对该方法的安全性、高效性及可行性进行评估。方法:研究纳入孤立肾鹿角形结石患者20例,对结石的位置和表面积进行统计。患者在知情同意后,先对其进行第一阶段的MPCNL治疗。术后5~7天,将第二阶段的MPCNL和FURSL相结合进行治疗。并对术中情况、结石清除率(SFR)和术后并发症进行评估,测量并记录患者术前、术后1个月以及每次复查时的血肌酐(Scr)、肾小球滤过率(GFR)和慢性肾脏疾病分级(CKD)。结果:所有患者均存在多个肾盏的鹿角形结石,结石平均大小为(1 099.9±843.95)mm2。所有患者均只有一处经皮入路,平均手术时间为(154.37±32.45)min,平均失血量为64(12~140)ml,最终SFR为90%。随访1个月,4例患者的CKD情况有所改善,2例CKD为5级的患者术后仍然需要透析,其余患者术前平均Scr为(187.16±94.12)μmol/L,术后1个月为(140.99±57.92)μmol/L,差异具有统计学意义(P=0.019)。GFR术前为(43.80±24.74)ml/min,术后随访1个月末为(49.55±21.18)ml/min,差异具有统计学意义(P≤0.05)。结论:MPCNL和FURSL联合治疗孤立肾鹿角形结石,可以有效地减少经皮入口的大小和数量,使得孤立肾结石患者的治疗更安全、可行且高效,进而得到满意的SFR,减少失血量及多入口相关的潜在并发症。在短期及长期愈后方面,该方法均不会对肾功能产生不利影响。  相似文献   
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The nucleus of the solitary tract (NST) processes gustatory and related somatosensory information rostrally and general viscerosensory information caudally. To compare its connections with those of other rodents, this study in the C57BL/6J mouse provides a subnuclear cytoarchitectonic parcellation (Nissl stain) of the NST into rostral, intermediate, and caudal divisions. Subnuclei are further characterized by NADPH staining and P2X2 immunoreactivity (IR). Cholera toxin subunit B (CTb) labeling revealed those NST subnuclei receiving chorda tympani nerve (CT) afferents, those connecting with the parabrachial nucleus (PBN) and reticular formation (RF), and those interconnecting NST subnuclei. CT terminals are densest in the rostral central (RC) and medial (M) subnuclei; less dense in the rostral lateral (RL) subnucleus; and sparse in the ventral (V), ventral lateral (VL), and central lateral (CL) subnuclei. CTb injection into the PBN retrogradely labels cells in the aforementioned subnuclei; RC and M providing the largest source of PBN projection neurons. Pontine efferent axons terminate mainly in V and rostral medial (RM) subnuclei. CTb injection into the medullary RF labels cells and axonal endings predominantly in V at rostral and intermediate NST levels. Small CTb injections within the NST label extensive projections from the rostral division to caudal subnuclei. Projections from the caudal division primarily interconnect subnuclei confined to the caudal division of the NST; they also connect with the area postrema. P2X2‐IR identifies probable vagal nerve terminals in the central (Ce) subnucleus in the intermediate/caudal NST. Ce also shows intense NADPH staining and does not project to the PBN. J. Comp. Neurol. 522:1565–1596, 2014. © 2013 Wiley Periodicals, Inc.  相似文献   
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Estrogens regulate key features of metabolism, including food intake, body weight, energy expenditure, insulin sensitivity, leptin sensitivity, and body fat distribution. There are two ‘classical’ estrogen receptors (ERs): estrogen receptor alpha (ERS1) and estrogen receptor beta (ERS2). Human and murine data indicate ERS1 contributes to metabolic regulation more so than ESR2. For example, there are human inactivating mutations of ERS1 which recapitulate aspects of the metabolic syndrome in both men and women. Much of our understanding of the metabolic roles of ERS1 was initially uncovered in estrogen receptor α-null mice (ERS1−/−); these mice display aspects of the metabolic syndrome, including increased body weight, increased visceral fat deposition and dysregulated glucose intolerance. Recent data further implicate ERS1 in specific tissues and neuronal populations as being critical for regulating food intake, energy expenditure, body fat distribution and adipose tissue function. This review will focus predominantly on the role of hypothalamic ERs and their critical role in regulating all aspects of energy homeostasis and metabolism.  相似文献   
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