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21.
T Isayama  H Iwasaki  M Kikuchi  S Yoh  N Takagishi 《Cancer》1990,65(8):1771-1781
A new cell line was established from a "neuroectodermal tumor of bone" affecting the right scapula of an 18-year-old man. The original neoplasm had dense proliferation of small round cells with abundant glycogen content and numerous Homer-Wright rosettes. The culture showed proliferation of small spindle cells with uniform oval nuclei and slender cytoplasmic processes. When the culture reached maximum density, rosette-like structures similar to those in the original tumor were formed. Under the influence of N6,O2'-dibutyryl adenosine 3',5'-cyclic monophosphoric acid (dibutyryl cAMP), the cultured cells expressed these rosette-like structures even in the lower cell concentration. Electron microscopy revealed that the cultured cells treated with dibutyryl cAMP contained high-density granules, well-developed microtubules, and abundant 10-nm filaments. By immunocytochemistry, neuron-specific enolase (NSE), and N-myc oncogene product were detected in the cultured cells as well as the original tumor. These results indicated the neuroectodermal origin of some of the small round cell tumors of bone.  相似文献   
22.
We report a case of giant testicular tumor. A 30-year-old man visited our department complaining of a painless swelling of the right scrotal contents. In chest X-ray and abdominal computerized tomography (CT) there were no abnormal findings. Serum alpha-fetoprotein, human chorionic gonadotropin and lactate dehydrogenase levels were normal. Right high orchiectomy was performed. The size of the removed specimen was 13.5 x 8.5 x 7.5 cm, and weight 530 g. The pathological diagnosis was immature teratoma. The patient has received no further therapy. There has been no recurrence for 7 months postoperatively.  相似文献   
23.
A clinical study was performed on the efficacy of intra-arterial chemotherapy using a reservoir system for advanced urological malignancies. The reservoir system was indwelted in the femoral subcutaneous layer by Seldinger's method. Fifteen cases of inoperable complicated advanced bladder cancer and 10 cases of postoperative local recurrent bladder cancer were administered intra-arterial chemotherapy using a reservoir system. Then, 23 cases of local relapsed prostate cancer and two cases of endpocrine-resistant prostate cancer were administered the chemotherapy. The administered anti-cancerous agents were methotraxate, cis-platinum and adriamycin, then 5-FU or carboplatin was administered as maintenance therapy. The mean number of courses of chemotherapy was six for bladder cancer and four for prostate cancer. During stabilization of the local lesion, no distant deterioration was recognized. The overall clinical efficacy was a positive response (PR) and no change (NC): for 18 and 7 cases of bladder cancer, and 11 and 14 cases of prostate cancer, respectively. The median duration of stabilization was 23 months for bladder cancer and 12 months for prostate cancer. The adverse effects were fever than those with systemic chemotherapy.  相似文献   
24.
A case of synchronous squamous cell carcinomas in the soft palate,larynx and esophagus is reported, along with findings of molecular-pathologicalanalysis. A biopsy sample from the aryngeal carcinoma revealedwell differentiated squamous cell carcinoma harboring two pointmutations at codons 144 and 148 of the p53 gene but not at codon299, and more than 50% of the cancer cells showed accumulationof p53 protein immunohistochemically. The esophageal tumor,which was moderately differentiated squamous cell carcinoma,showed immunoreactivity for p53 within the nuclei of 25–50%of cancer cells with a missense mutation at codon 299 but notat codon 144 or 148. This cancer also showed immunoreactivityfor transforming growth factor alpha. On the other hand, thepoorly differentiated squamous cell carcinoma in the soft palateshowed negative immunoreactivity for p53 and no point mutationin exons 5 to 8 of the gene. These results suggest that thethree synchronous squamous cell carcinomas arose as independentevents.  相似文献   
25.
To elucidate the precise origin and characteristics of the proliferating cells in malignant fibrous histiocytoma (MFH), the authors analyzed 33 MFH tumors, using immunohistochemical techniques with a panel of 12 antibodies. All three types of MFH cells (spindle cells, polygonal cells, and bizarre giant cells) stained positively for mesenchymal antigens (FU3 and vimentin) but did not stain for macrophage/histiocyte markers (HAM 56 and CD68). Therefore, the MFH cells may not represent true histiocytes, although they may be mesenchymal-derived cells behaving as "facultative histiocytes" with superficial resemblance to actual histiocytes. Normal histiocytes in the stroma tested positive for macrophage/histiocyte antigens; the most common cells were HAM 56-positive cells constituting 30-80% of nonneoplastic stromal cells, followed by those positive for CD68 (10-50%), Mac 387 (less than 2%), and S-100 protein (less than 1%). Our results indicate the presence of heterogeneity of "histiocytic" cells in MFH. Proliferating-cell nuclear antigen (PCNA) was expressed not only in the spindle and polygonal MFH cells but also in the bizarre giant cells. These findings suggest that all three types of MFH cells participate in the proliferative compartment of MFH. Uneven PCNA staining of the irregular nuclear segments of the bizarre giant cells may result in abnormal DNA synthesis, possibly contributing to the marked diversity of nuclear morphology in MFH. Touton-type and osteoclast-like giant cells did not stain for PCNA but stained positively for histiocytic markers. Therefore, these giant cells may lack proliferative activity and probably result from normal histiocytes fusing together.  相似文献   
26.
Agents that disrupt functions of the endoplasmic reticulum (ER) induce expression of ER stress-response genes including ER chaperones. Increased expression of the major ER chaperone, Grp78, protects cells, including renal epithelial cells, from chemically induced injury and death in vitro. In this study, we determined if pharmacological manipulation of the ER stress-response gene is an effective strategy to protect the kidney from chemical stress in vivo. Treatment with trans-4,5-dihydroxy-1,2-dithiane (DTTox), a novel inducer of ER stress proteins, stimulated a time-and dose-dependent increase in Grp78 expression in the kidney, but it did not cause detectable injury. Furthermore, prior treatment with DTTox protected the proximal tubular epithelium against a subsequent challenge with the nephrotoxicant S-(1,1,2,2,-tetrafluoroethyl)-L-cysteine (TFEC). In contrast, activating a heat shock response did not have a protective effect. Prior treatment with DTTox did not reduce covalent binding of radiolabeled reactive metabolites of (35)S-TFEC to renal proteins, indicating that protection was not due to an effect on the metabolic activation of TFEC to the reactive metabolite(s) responsible for renal injury. Antisense grp78 expression in the renal epithelial cell line LLC-PK1 blocked the DTTox-induced Grp78 increase and ablated the protective effect against TFEC damage, indicating that the induction of grp78 expression and the ER stress response were critical for the protective effect of DTTox. These findings suggest that increased expression of Grp78 plays a major role in the protection of renal epithelial cells from reactive intermediate-induced chemical injury in vivo and that pharmacological manipulation is an effective strategy to prevent damage by some classes of nephrotoxicants.  相似文献   
27.
A 49-yr-old Japanese woman underwent upper gastrointestinal endoscopy because of nonspecific dyspepsia. Endoscopy revealed a flat elevated lesion about 15 mm in diameter adjacent to the duodenal papilla, the surface of which was uneven and covered with whitish granules. Based on the results of histological examination with immunohistochemistry (positive for CD10, CD20, CD79a, and bcl-2 protein, negative for CD5 and cyclin D1), a diagnosis of grade 1/3 follicular lymphoma was established. Systemic staging examinations suggested the lymphoma was restricted to the mucosa and superficial portion of the submucosa in the duodenal wall. The patient was treated with a combination of CHOP chemotherapy (cyclophosphamide, doxorubicin, vincristine, and prednisolone) and monoclonal anti-CD20 antibody (rituximab), in addition to radiotherapy. After six courses of this combination chemotherapy, complete regression of the lymphoma was observed. Although reports of small duodenal lymphoma (<20 mm or localized to the mucosa or submucosa) are extremely rare, the features of this case are characteristic of small duodenal lymphoma in terms of evolution around the ampulla of Vater, low-grade follicular type, occurrence in a women, occurrence in the fourth decade of life, and favorable outcome, and this type of tumor may need to be distinguished by pathogenesis and clinical behavior from various other gastrointestinal lymphomas.  相似文献   
28.
We report a very rare case of primary gastric small cell carcinoma (GSCC) that was accompanied with gastric tubular adenocarcinoma. A male in his 60s had an elevated tumor with a central ulceration in the middle stomach. The patient underwent a distal gastrectomy with lymph node dissection. The pathological examination showed two separated lesions of the stomach, which contained the components of primary GSCC and primary gastric tubular adenocarcinoma. Immunohistochemical (IHC) examination demonstrated that the tumor cells in the small cell carcinoma stained positive for synaptophysin, chromogranin A, and neural cell adhesion molecule (NCAM). GSCC cells and adenocarcinoma cells independently metastasized to each regional lymph node. Further studies on the biological behavior of individual tumors may allow the development of new treatment strategies for GSCC.  相似文献   
29.
An association between the development of overall or specific immune-related adverse events (irAEs) and outcomes of immune checkpoint inhibitors has recently been suggested. To address this emerging association in patients with urothelial cancer receiving pembrolizumab, we conducted a multicenter retrospective analysis, which is the first and largest in an Asian cohort as well as a systematic literature review. We retrospectively evaluated 97 patients with advanced urothelial cancer treated with pembrolizumab as second- or later-line treatment between January 2018 and March 2019. irAEs were categorized by the involved organs and graded using Common Terminology Criteria for Adverse Events version 5.0. Associations between irAEs and pembrolizumab efficacy, including objective response rate (ORR), progression-free survival (PFS), and overall survival (OS), were evaluated. In our review of the literature, 28 studies, including 9 studies involving patients with urothelial cancer and 19 studies reporting the association between outcomes and spectrum of irAEs, were analyzed. Patients with irAEs had significantly higher ORR (52% vs. 16%, P < .01), longer PFS (11.0 months vs. 3.6 months, P < .01) and OS (median not reached vs. 13.1 months, P = .12) than in patients without irAEs. Endocrine (P = .02), pneumological (P = .06), and other (gastrointestinal, hematological, hepatic) (P = .04) irAEs were associated with increased ORR, whereas skin irAEs were not. Endocrine irAEs (P = .04) was associated with improved OS, whereas pneumological and skin irAEs were not. The association between the occurrence of irAEs and clinical efficacy of immune checkpoint inhibitors was consistently supported by the multiple studies we reviewed. The association between clinical outcomes and the spectrum of organs/systems affected by irAEs seems to be inconsistent and could be dependent on tumor type. irAEs were associated with a higher ORR and better survival of patients with advanced urothelial cancer treated with pembrolizumab.  相似文献   
30.

Background

A pulmonary hypertensive crisis (PHC) can be a life-threatening condition. We established a PHC model by exposing rats with monocrotaline (MCT)-induced pulmonary hypertension to acute hypoxia, and investigated the effects of vasopressin, phenylephrine, and norepinephrine on the PHC.

Methods

Four weeks after MCT 60 mg kg?1 administration i.v., right ventricular systolic pressure (RVSP), systolic BP (SBP), mean BP (MBP), cardiac index (CI), and pulmonary vascular resistance index (PVRI) were measured. PHC defined as an RVSP exceeding or equal to SBP was induced by changing the fraction of inspiratory oxygen to 0.1. Rats were subsequently treated by vasopressin, phenylephrine, or norepinephrine, followed by assessment of systemic haemodynamics, isometric tension of femoral and pulmonary arteries, cardiac function, blood gas composition, and survival.

Results

PHC was associated with increased RV dilatation and paradoxical septal motion. Vasopressin increased MBP [mean (standard error)] from 52.6 (3.8) to 125.0 (8.9) mm Hg and CI from 25.4 (2.3) to 40.6 (1.8) ml min?1 100 g?1 while decreasing PVRI. Vasopressin also improved RV dilatation, oxygenation, and survival in PHC. In contrast, phenylephrine increased MBP from 54.8 (2.3) to 96.8 (3.2) mm Hg without improving cardiac pump function. Norepinephrine did not alter MBP. Vasopressin contracted femoral but not pulmonary arteries, whereas phenylephrine contracted both arterial beds. Hence, improvements with vasopressin in PHC might be associated with decreased PVRI and selective systemic vasoconstriction.

Conclusions

In this rat model of a PHC, vasopressin, but not phenylephrine or norepinephrine, resulted in better haemodynamic and vascular recovery.  相似文献   
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