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51.
Role of peroxisome proliferator-activated receptor-gamma in maintenance of the characteristics of mature 3T3-L1 adipocytes 总被引:4,自引:0,他引:4
Peroxisome proliferator-activated receptor (PPAR)-gamma plays an important role in adipogenesis. However, the functions of PPAR-gamma in differentiated adipocytes have remained unclear. The role of PPAR-gamma in mature 3T3-L1 adipocytes was therefore investigated by overexpression of a dominant negative mutant of this protein (PPAR-gamma-DeltaC) that lacks the 16 COOH-terminal amino acids and that has been shown to prevent the thiazolidinedione-induced differentiation of 3T3-L1 cells into adipocytes. Overexpression of PPAR-gamma-DeltaC in mature 3T3-L1 adipocytes by adenovirus gene transfer resulted in a decrease in both cell size and intracellular triglyceride content, an increase in the extent of lipolysis, and a reduction in the rate of free fatty acid uptake. Furthermore, overexpression of this mutant reduced the abundance of mRNAs for several key enzymes that contribute to triglyceride and free fatty acid metabolism as well as the amounts of GLUT4, insulin receptor, insulin receptor substrate (IRS), and C/EBPalpha mRNAs. It also reduced both the concentration of IRS2 and the insulin-stimulated glucose uptake. These results suggest that PPAR-gamma plays an important role in mature 3T3-L1 adipocytes at least in part by maintaining the expression of genes that confer the characteristics of mature adipocytes. 相似文献
52.
Katoh M Yoshino M Asaoka K Aoki T Imamura H Kashiwazaki D Takano K Aida T 《Surgical neurology》2007,68(4):457-460
BACKGROUND: Cerebral amyloid angiopathy is a well-known disease that is predominantly recognized in elderly people and repeatedly causes large subcortical hemorrhages. These hemorrhages may be derived from vessel wall weakness because of Abeta depositions in the wall of the cortical and leptomeningeal arteries. Although vessel ruptures in CAA have been thought to occur in cortical arteries, it was recently demonstrated that the primary hemorrhage occurs in the subarachnoid space, particularly the cerebral sulci, as a result of multiple ruptures of meningeal arteries in some cases of subcortical hematoma caused by CAA. CASE DESCRIPTION: Case patient 1 was a 74-year-old woman who presented with epileptic seizure. A restricted SAH in the right frontal lobe was observed on MRI. Thirty-three days later, left hemiparesis occurred suddenly and a huge subcortical hematoma was observed in the right frontal lobe on CT. The hematoma was removed, and the patient was pathologically diagnosed with amyloid angiopathy. Case patient 2 was a 73-year-old man who presented with epileptic seizure. A restricted SAH in the right frontal lobe was observed on MRI. Twenty days later, left hemiparesis occurred suddenly and a huge subcortical hematoma was observed in the right frontoparietal area on CT. Hematoma removal was performed on both patients, and they were diagnosed pathologically with amyloid angiopathy. CONCLUSIONS: We report on the cases of 2 patients with CAA who presented with epileptic seizure and were found to have a restricted subarachnoid hematoma in the cerebral sulcus on MRI before their subcortical hemorrhages occurred. Both cases were diagnosed pathologically. This demonstrated that vessel ruptures in CAA can occur in the subarachnoid space, particularly the cerebral sulci, as a result of ruptures of meningeal arteries. A restricted SAH on CT/MRI could be a warning sign of a huge subcortical hemorrhage in CAA. 相似文献
53.
Repair of an Abdominal Aortic Aneurysm with a Remarkably Dilated Meandering Artery: Report of a Case
Sakamoto S Yamauchi S Yamashita H Imura H Maruyama Y Ochi M Shimizu K 《Surgery today》2007,37(2):133-136
A 73-year-old man on dialysis for chronic renal dysfunction was referred to our hospital for surgical treatment of an abdominal
aortic aneurysm (AAA). Preoperative angiography showed a remarkably developed meandering artery branching from the inferior
mesenteric artery (IMA). The superior mesenteric and celiac arteries were occluded at the origin, and all blood flow to the
abdominal organs was apparently supplied by collateral circulation from the IMA. Considering the risk of mesenteric ischemia
after aortic clamping in conjunction during surgery, we used a perfusion catheter with a 12-F balloon to create a shunt to
the IMA from the subclavian artery. The operation was successful and the patient recovered uneventfully. We describe this
surgical procedure for its effectiveness in preventing postoperative mesenteric ischemia in a rare case of an AAA with complex
branching lesions. 相似文献
54.
Prognostic Significance of Immunohistochemically Detected Blood and Lymphatic Vessel Invasion in Colorectal Carcinoma: Its Impact on Prognosis 总被引:6,自引:0,他引:6
Liang P Nakada I Hong JW Tabuchi T Motohashi G Takemura A Nakachi T Kasuga T Tabuchi T 《Annals of surgical oncology》2007,14(2):470-477
Background The prognostic significance of blood vessel invasion (BVI) and lymphatic vessel invasion (LVI) is unclear. Because of the
absence of specific markers for venous and lymphatic vessels, earlier studies could not reliably distinguish between BVI and
LVI.
Methods By immunostaining for podoplanin and CD34 antigen, we retrospectively investigated LVI and BVI in 419 tissue specimens of
colorectal carcinoma. We performed univariate and multivariate analysis of the clinicopathologic features, frequency of recurrence,
and outcome of patients with or without LVI and BVI.
Results The use of hematoxylin and eosin (H&E) staining to identify BVI and LVI yielded a false positive rate of 9.1% and false negative
rate of 12.6%. The incidence of BVI was significantly higher among tumors with LVI than tumors without LVI (P <.001). In logistic multivariate analysis, only LVI (P < .001) was associated with lymph node metastasis and BVI (P = .015) was associated with distant recurrence. Calculating the prognostic relevance, both two invasion types correlated
with decreased survival in univariate analysis (both P <.001). In multivariate analysis, BVI (P =.024), lymph node status (P =.003) and tumor stage (P <.001) remained statistically significant factors for survival.
Conclusions Our results suggest that immunohistologic evaluation of BVI and LVI could be useful in colorectal carcinoma indicating the
risk of lymph node metastasis and recurrence, thereby contributing to prognostic evaluation. 相似文献
55.
Isolated granulomatous inflammation of the appendix is extremely rare, and its etiology is still unknown. Thus, differentiating
between idiopathic granulomatous appendicitis and isolated appendiceal Crohn's disease is difficult. We report a case of idiopathic
granulomatous appendicitis with long-term follow-up after surgery. A 26-year-old woman was referred to our hospital for investigation
of persistent right lower abdominal pain. Abdominal computed tomography showed a mass, suggesting an inflammatory tumor around
the appendix; thus, we suspected subacute appendicitis and performed laparoscopically assisted ileocecal resection. Histological
examination of the resected specimen revealed several noncaseous epithelioid granulomas in the wall of the appendix, but no
foreign bodies, obstructing lesions, or parasites. Stains for acid-fast bacillus and fungi, and serology for yersinia were
all negative. The patient has been followed up for 9 years and remains asymptomatic. This clinical course suggests that her
isolated granulomatous appendicitis was idiopathic granulomatous appendicitis unrelated to Crohn's disease. 相似文献
56.
Ike A Tokuhiro K Hirose M Nozaki M Nishimune Y Tanaka H 《International journal of andrology》2007,30(5):462-475
The comprehensive changes in testicular gene expression before and after haploid germ cell differentiation were examined using microarray analysis. Approximately 14,000 expressed sequence tag (EST) clones of Mouse FANTOM Array ver.1 were hybridized with probes generated from mRNA of adult and juvenile (17 days postpartum) testes before the onset of spermiogenesis. Of 1315 genes that exhibited reproducible changes in expression (p < 0.05), 46% exhibited an increase of twofold or more in adults compared to juveniles, and 22% a decrease of twofold or more. The analysis not only confirmed the reported haploid-specific expression of several known genes, but also provided new information on the differential expression of various other genes, including upregulated genes such as Allc and Skd3 and downregulated genes such as hbb b1, before or after the onset of spermiogenesis. Based on the fundamental difference in expression profiles, and molecular functions of the encoded products, the genes were classified into several groups: postmeiotically upregulated genes encoding various enzymes, structural and regulatory proteins, and chaperones, and downregulated genes encoding haemoglobins and oxidation/reduction-related proteins or the machinery associated with protein synthesis, such as ribosomal proteins. 相似文献
57.
58.
Kano H Mizuta K Sakakihara Y Kato H Miki Y Shibuya N Saito M Narita M Kawarasaki H Igarashi T Hashizume K Iwata T 《Transplantation》2002,74(4):543-550
BACKGROUND: Infection is a serious complication after liver transplantation. Immunization is one means of controlling infections. The objective of this study was to investigate the efficacy and safety of simultaneous administration of several vaccines before transplantation and the efficacy and safety of administration under immunosuppressive conditions after transplantation. METHODS: Fifty-eight patients who underwent living-related liver transplantation between April 1994 and March 2000 were included in this study. Simultaneous administration of a maximum of six vaccines was performed in a short period of time before transplantation. We also readministered vaccines to 15 patients with waning antibody titers after transplantation from June 1999. We investigated whether patients could seroconvert for measles, rubella, mumps, and varicella after immunization and how long antibody titers could be retained by measuring them several times throughout the period before and after transplantation. We also examined side effects caused by immunization. RESULTS: The rates of seroconversion against measles, rubella, mumps, and varicella after the pretransplantation vaccination were 82%, 100%, 90%, and 95%, respectively. The rates of reseroconversion against measles, rubella, mumps, and varicella after the posttransplantation revaccination were 85%, 100%, 100%, and 71%, respectively. Although antibody titers against these viruses generally waned with time, no patient exhibited any serious illness or side effects. CONCLUSION: Although 12 of 58 patients (21%) had an infection, pretransplantation immunization was effective to prevent serious illness, especially for the 6 months after transplantation. Posttransplantation live-vaccine administration under immunosuppressive conditions is effective and safe. 相似文献
59.
Takeshi Masaki Masami Nishino Masayuki Taniike Nobuhiko Makino Hiroyasu Kato Yasuyuki Egami Ryu Shutta Hitoshi Yamaguchi Jun Tanouchi Yoshio Yamada 《Journal of Echocardiography》2010,8(4):118-120
Quadricuspid aortic valve (QAV) is a rare congenital aortic valve anomaly. We present two cases of QAV diagnosed by using
echocardiography including transesophageal echocardiography (TEE) and cardiac computed tomography (CT). The first case, QAV
with four equal-sized cusps, was identified in a 58-year-old man. The second case, QAV with a small accessory cusp between
the right coronary and non-coronary cusp, was identified in a 42-year-old man. TEE and cardiac CT could lead to accurate diagnosis
of QAV. QAV in these two patients could be diagnosed before indication for surgery but it is necessary to continue careful
follow-up. 相似文献
60.
Kajiwara K Saito K Yoshikawa K Ideguchi M Nomura S Fujii M Suzuki M 《Neurologia medico-chirurgica》2010,50(9):749-755
The recent clinical results are reviewed of stereotactic radiosurgery/radiotherapy for the treatment of pituitary adenomas. The outcomes of pituitary adenomas treated by stereotactic radiosurgery/radiotherapy with gamma knife, CyberKnife, or linear accelerator (LINAC) radiosurgery were evaluated from articles published after 2004. Each study was evaluated for the number of patients, radiosurgical parameter (marginal dose), length of follow up, tumor growth control, rate of hormonal normalization in secretary adenomas, and adverse events. After gamma knife radiosurgery, the tumor reduction rates varied from 42.3% to 89% in non-secreting adenomas. However, the tumor control rates in non-secreting adenomas were more than 90% in most studies. In growth hormone-secreting adenomas, the rates of insulin-like growth factor-1 normalization ranged from 36.9% to 82%. In adrenocorticotropin-secreting adenomas, the rates for 24-hour urine free cortisol normalization ranged from 27.9% to 54%. In prolactin-secreting adenomas, the prolactin normalization ranged from 17.4% to 50%. New hormonal deficits ranged from 0% to 34%. New visual deficits were relatively low. The number of patients treated with CyberKnife and LINAC radiosurgery/radiotherapy was small and follow-up periods were relatively short compared to those with gamma knife treatment, but the clinical outcomes after these therapies were similar to those after gamma knife therapy. Image-guided stereotactic radiosurgery/radiotherapy with the gamma knife, CyberKnife, or LINAC system is effective and safe against pituitary adenomas. Careful long-term follow up of the patients is necessary because of long-term anti-tumor effects and delayed adverse events. 相似文献