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31.

INTRODUCTION

Malignant peripheral nerve sheath tumors (MPNSTs) are rare, up to one half of the MPNSTs occur in patients with neurofibromatosis type-1 (NF-1), while the rest are sporadic. Here, we present a 52-year-old woman with MPNST of the vulva without NF-1. We will discuss basics of the disease, treatment options and follow-up strategies.

PRESENTATION OF CASE

52-year-old female admitted to our hospital with complaint of abnormal uterine bleeding and rapidly growing vulvar mass. Excisional biopsy of the mass showed MPNST of the vulva. Afterwards, the patient underwent radical vulvectomy with inguinofemoral lymph node dissection. Short after the surgery, multiple lung metastasis were shown and responded to chemotherapy, but rapid local recurrence occurred short after the completion of the chemotherapy.

DISCUSSION

The primary treatment option in MPNSTs is surgical excision with or without adjuvant therapy. There is not enough data about the role of systemic chemotherapy in the management of MPNSTs and it still remains controversial.

CONCLUSION

In general, radiation therapy has not been demonstrated to improve overall survival. Complete surgical resection of the primary tumor is the mainstay of the treatment.  相似文献   
32.
Extrusion of intracanal debris as well as irrigants is a common occurrence during root canal treatment, and no instrument or technique has thoroughly solved this problem. Because flare‐ups may arise with any irritation directed towards periapical tissues, a shaping or irrigation technique should minimize the risk of apical extrusion, even though it may not be prevented. There has been a rapid evolution of root canal instruments and irrigation systems through the last decade, and many have been assessed for their debris extrusion potential. The purpose of this review was to identify publications regarding the evaluation of debris, bacteria and irrigant extrusion during root canal treatment. A PubMed, Ovid and MEDLINE search was conducted using the keywords “apical extrusion”, “debris extrusion” and “endodontic treatment”. The literature search extended over a period of more than 30 years up to 2012. Content of the review was limited to apical extrusion of debris and irrigants, extrusion of liquid by irrigation methods and bacterial extrusion. Issues relevant to apical extrusion were obtained by further search in the reference sections of the retrieved articles. The review provides an update on the current status of apical extrusion.  相似文献   
33.
Hemorrhagic stroke due to ruptured brain arteriovenous malformations (AVMs) is a common cause in young stroke patients. When the ruptured AVMs are in deep location, the choice of endovascular intervention with the arterial approach to AVM embolization is routine but in many cases, it is not feasible due to the inability to access because of the small and tortuous arterial branch, however, the intravenous approach also results in high complete obliteration rates but also carries a higher risk of stroke than the intra-arterial route. We describe a 36-year-old female patient diagnosed with intracranial and intraventricular hemorrhage who underwent complete transvenous embolization of the ruptured AVMs, and achieved near-complete clinical recovery after 1 month with the modified Rankin scale 1.  相似文献   
34.
35.
Melanogenesis is the production of melanin from tyrosine by a series of enzyme-catalyzed reactions, in which tyrosinase and DOPA oxidase play key roles. The melanin content in the skin determines skin pigmentation. Abnormalities in skin pigmentation lead to various skin pigmentation disorders. Recent research has shown that the expression of EMP2 is much lower in melanoma than in normal melanocytes, but its role in melanogenesis has not yet been elucidated. Therefore, we investigated the role of EMP2 in the melanogenesis of MNT1 human melanoma cells. We examined TRP-1, TRP-2, and TYR expression levels during melanogenesis in MNT1 melanoma cells by gene silencing of EMP2. Western blot and RT-PCR results confirmed that the expression levels of TYR and TRP-2 were decreased when EMP2 expression was knocked down by EMP2 siRNA in MNT1 cells, and these changes were reversed when EMP2 was overexpressed. We verified the EMP2 gene was knocked out of the cell line (EMP2 CRISPR/Cas9) by using a CRISPR/Cas9 system and found that the expression levels of TRP-2 and TYR were significantly lower in the EMP2 CRISPR/Cas9 cell lines. Loss of EMP2 also reduced migration and invasion of MNT1 melanoma cells. In addition, the melanosome transfer from the melanocytes to keratinocytes in the EMP2 KO cells cocultured with keratinocytes was reduced compared to the cells in the control coculture group. In conclusion, these results suggest that EMP2 is involved in melanogenesis via the regulation of TRP-2 expression.  相似文献   
36.
37.
CD31(+)CD45RA(+)RO(-) lymphocytes contain high numbers of T cell receptor circle (TREC)-bearing T cells; however, the correlation between CD31(+)CD4(+) lymphocytes and TREC during aging and under lymphopenic conditions has not yet been sufficiently investigated. We analyzed TREC, telomere length and telomerase activity within sorted CD31(+) and CD31(-) CD4(+) lymphocytes in healthy individuals from birth to old age. Sorted CD31(+)CD45RA(+)RO(-) naive CD4(+) lymphocytes contained high TREC numbers, whereas CD31(+)CD45RA(-)RO(+) cells (comprising < or =5% of CD4(+) cells during aging) did not contain TREC. CD31(+) overall CD4(+) cells remained TREC rich despite an age-related tenfold reduction from neonatal (100 : 1000) to old age (10 : 1000). Besides a high TREC content, CD31(+)CD45RA(+)RO(-)CD4(+) cells exhibited significantly longer telomeres and higher telomerase activity than CD31(-)CD45RA(+)RO(-)CD4(+) cells, suggesting that CD31(+)CD45RA(+)RO(-)CD4(+) cells represent a distinct population of naive T cells with particularly low replicative history. To analyze the value of CD31 in lymphopenic conditions, we investigated six children after allogeneic hematopoietic stem cell transplantation (HSCT). Reemerging overall CD4(+) as well as naive CD45RA(+)RO(-)CD4(+) cells predominantly expressed CD31 and correlated well with the recurrence of TREC 5-12 months after HSCT. Irrespective of limitations in the elderly, CD31 is an appropriate marker to monitor TREC-rich lymphocytes essentially in lymphopenic children after HSCT.  相似文献   
38.
We report a case of severe subcapsular hepatic steatosis in a middle-aged woman with diabetic nephropathy requiring continuous ambulatory peritoneal dialysis (CAPD). The CT appearances of the liver were initially suspected to be due to embolic infarcts. However, an accurate diagnosis was made only after a history of intraperitoneal insulin administration was elicited, and this was confirmed on MRI with chemical shift gradient-echo pulse sequences. Haemodialysis was recommenced, and follow-up imaging 4 years later showed complete resolution of subcapsular hepatic steatosis.Subcapsular hepatic steatosis is a rare and unique form of non-alcoholic fatty liver, occurring only in individuals with diabetic nephropathy receiving continuous ambulatory peritoneal dialysis (CAPD) with intraperitoneal insulin. Imaging findings are classical, and with the appropriate history of intraperitoneal insulin administration, an accurate diagnosis can be made. Given that this disease entity has only recently been described, we hope to highlight its typical imaging appearances, which may otherwise be misinterpreted as a more insidious finding, thus averting unnecessary intervention.  相似文献   
39.
Angiogenesis is involved in tumor progression of oral squamous cell carcinoma (OSCC). In this study, we have investigated by immunohistochemistry vascular endothelial growth factor (VEGF) expression in tumor cells and we have correlated VEGF expression to microvessel area, evaluated by using CD105 as a marker of endothelial cells, in bioptic specimens of 54 human OSCC. Results demonstrated that VEGF is highly expressed in OSCC tumor specimens when compared to pre-neoplastic and normal tissues, without differences between the edge and inside the tumor. Moreover, VEGF expression is reduced in poor differentiated OSCC tumors when compared to moderate and good differentiated forms, and tumor microvessel area is higher in tumors when compared to pre-neoplastic lesions and normal tissues. Finally, VEGF and CD105 may be considered as reliable markers of tumor angiogenesis and progression in OSCC, even if we did not demonstrate any correlation between VEGF expression, tumor microvascular area, clinical stage, and lymph node status.  相似文献   
40.

Purpose(s)

To evaluate results of neoadjuvant chemotherapy (NACT) following debulking surgery in patients with extensive metastatic disease and/or poor medical performance

Method(s)

Advanced stage epithelial ovarian cancer patients were treated with either NACT followed by debulking surgery or primary surgery followed by adjuvant chemotherapy after assessment of the extent of disease by laparoscopy or laparotomy.

Results

Out of 297, 223 patients were in the primary surgery group, whereas 74 of them met NACT criteria. Optimal cytoreduction rates were 63.2 % in primary surgery group and 60.8 % in NACT group, respectively (p: 0.709). In the primary surgery group, the overall survival was significantly higher (p: 0.002). Mean patient age was more advanced (p: 0.014) and the performance status of patients was poorer (p < 0.001) in NACT group. Only patient group (primary surgery or neoadjuvant chemotherapy) (p: 0.001) retained significance as predictors of survival in multivariate analyses.

Conclusion(s)

Improved rate of optimal cytoreduction with NACT in advanced ovarian cancer patients does not prolong survival. The extent of disease at diagnosis is the primary determinant of survival. Randomizing patients with equally extensive disease and performance status to either NACT or primary debulking surgery in a future study will better clarify benefits attributed to NACT.  相似文献   
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