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991.
Uchida  T; Watanabe  T; Kinoshita  T; Murate  T; Saito  H; Hotta  T 《Blood》1995,86(7):2724-2731
The CDKN2 gene located on chromosome 9p21 encodes the cyclin-dependent kinase-4 inhibitor p16. This gene is a putative tumor-suppressor gene because of its frequent alterations in many kinds of tumor cell lines. We analyzed the CDKN2 gene to evaluate its alterations in 52 primary specimens of non-Hodgkin's lymphoma (NHL) or chronic lymphocytic leukemia (CLL) of B-cell origin by Southern blot analysis, polymerase chain reaction-mediated single-strand conformation polymorphism (PCR- SSCP) analysis, and direct sequencing. By Southern blot analysis, we showed homozygous deletion of the CDKN2 gene in 3 of 42 patients with B- NHL (7.1%). After screening by PCR-SSCP analysis, direct sequencing identified one missense mutation at codon 72 (nucleotide 233) and two frameshifts due to a 35-bp deletion arising at codon 49 (nucleotides 163 to 175) in patients with B-NHL (3 of 42, 7.1%). In the patient carrying the missense mutation, hemizygous deletion of the CDKN2 gene was also suspected. In this study, we detected alterations in CDKN2 in 6 of 42 patients (14.3%) with B-NHL and in none of 10 patients with B- CLL. Our results suggest that the CDKN2 alterations contribute in tumorigenesis in some patients with B-NHL.  相似文献   
992.
The last decade has witnessed a phenomenal increase in our understanding of the biological role of lysophosphatidic acid (LPA) and has led to an appreciation of this critical serum-derived growth factor released from platelets. We herein summarize recent observations that collectively support the hypothesis that LPA may play a key role in the pathogenesis of initiation and progression of proliferative glomerulonephritis. LPA synergistically stimulates mesangial cell proliferation in combination with platelet-derived growth factor in primary culture. The mechanism of co-mitogenesis is likely to be mediated by the prolonged activation of mitogen-activated protein kinase which is stimulated by platelet-derived growth factor and LPA through different mechanisms. LPA contracts cultured mesangial cells and has properties in common with other pressor molecules including mobilization of intracellular Ca2+ and promotion of Ca2+ entry through dihydropyridine-sensitive calcium channels. LPA receptor mRNA has been identified in isolated glomeruli dissected from renal biopsy samples of patients with IgA nephropathy. All of these facts have led us to postulate that LPA is produced within glomeruli and that LPA's mitogenic as well as haemodynamic action contribute to the pathological process of mesangial proliferative glomerulonephritis. The possible production of LPA as an autocrine factor from mesangial cells themselves has also been discussed.  相似文献   
993.
In view of the anomalous expression of blood group and related antigens in the gastric mucosae of patients with malignant and premalignant diseases of the stomach, and the potential clinical value of their measurement, a preliminary study has been performed on the blood group antigens A, B, H, Lea, Leb, and I(Ma) in glycoprotein rich extracts of the resting and tetragastrin stimulated gastric juice of patients without evidence of gastric cancer. The aim has been to assess whether the antigenic profiles known to distinguish the gastric mucosae of secretors from those of non-secretors are reflected in the glycoproteins of gastric juice. Antigenic profiles which distinguish secretors from non-secretors were observed in the stimulated rather than the resting gastric juice as follows: the A, B or H antigens but not I(Ma) were strongly expressed in the glycoproteins of secretors, while I(Ma) was the antigen characteristic of non-secretors. On the other hand, there was considerable overlap in the Lea and Leb antigen values in the resting and stimulated gastric juice of secretors and non-secretors. Among these antigens, I(Ma) is known to appear as a neo-antigen in the gastric mucosae of secretors with malignant and premalignant diseases of the stomach. Thus this antigenic determinant is potentially a clinically useful marker in the gastric juice of 75% of the population who are secretors. The clinical value of the levels of this antigen in the gastric juice now deserves investigation.  相似文献   
994.
Reactive lymphoid hyperplasia (RLH) of the liver is an extremely rare lesion characterized by the proliferation of non-neoplastic lymphocytes forming follicles. Hepatic RLH is known to be associated with gastrointestinal carcinoma and autoimmune diseases including primary biliary cirrhosis (PBC). We report a case of hepatic RLH in a patient with PBC and gastric cancer. A 68 year old Japanese woman with a 10 year history of liver enzyme abnormality was admitted. Laboratory testing revealed that her anti-mitochondrial antibody was markedly elevated. Five mo after the diagnosis of PBC, she was found to have gastric cancer. Abdominal computed tomography disclosed a liver nodule in S8, suggesting metastatic gastric carcinoma. Histopathologically, the resected liver lesion comprised of a nodular proliferation of small lymphocytes with lymphoid follicles. This is the first reported case of hepatic RLH in a patient with both PBC and gastric cancer. Pre-operative diagnosis of hepatic RLH by clinical imaging is extremely difficult. Therefore, a needle biopsy could be useful to make a diagnosis of hepatic RLH, especially to differentiate from metastatic gastrointestinal carcinoma.  相似文献   
995.
Ampulla cardiomyopathy is named after the echocardiographic abnormalities occurring in this condition, characterized by extensive akinesis (ballooning ) of the apical region with hypercontraction of the basal segment of the ventricle. We describe 3 young female anorexia nervosa patients showing evidence of this cardiac complication after hypoglycemia. One case was complicated by echocardiographically confirmed ampulla cardiomyopathy while the other 2 patients showed increases in myocardial enzymes and transient electrocardiographic abnormalities consistent with this complication. The precipitating event for all three patients was hypoglycemic coma, and this is the first case report in which this factor lead to the complication of ampulla cardiomyopathy in anorexia nervosa patients.  相似文献   
996.
BACKGROUND: Although numerous studies have demonstrated a positive association of high-sensitivity C-reactive protein (CRP) with the incidence of coronary heart disease (CHD), little information exists regarding this issue in Japanese. METHODS AND RESULTS: The association between CRP and the Framingham Risk Score (FRS) was investigated in 2,523 middle-aged Japanese men without a medical history of CHD. CRP was significantly associated with this score obtained from all FRS factors. After dividing subjects into 4 categories of relative risk estimate for CHD, the geometric mean of CRP (mg/L) increased gradually with the CHD risk (below average: 0.39 [95% confidence interval, 0.37-0.41], average: 0.58 [0.50-0.67], moderately above average: 0.70 [0.57-0.86], high: 0.79 [0.58-1.09], trend p<0.001). However, it should be noted that the mean CRP concentration of the high-risk group was only 0.79 mg/L and a greater proportion (63.8%) of the high-risk subjects was in the low-risk range of CRP (<1 mg/L). CONCLUSIONS: Circulating CRP well reflect the estimated CHD risk, indicating that CRP may be useful for coronary risk stratification in Japanese also. However, the details of the CRP level in Japanese must be investigated further by prospective studies to determine the Japanese-specific cutoff points for CHD risk evaluation.  相似文献   
997.
OBJECTIVE: Although all the mechanisms of elimination of hepatitis C virus (HCV) by Interferon (IFN) have not been fully elucidated, the 2'-5'-oligoadenylate (2-5A) system is one of the mechanisms of the antiviral effect of IFN. Consequently, the measurement of 2'-5'-oligoadenylate synthetase (2-5AS) activity could be useful for the evaluation of IFN treatment. This retrospective study was aimed at assessing whether 2-5AS activity functions as a clinical marker of virological response to PEG-interferon-alpha2b (PEG-IFN) plus ribavirin therapy of chronic hepatitis C. METHODS: The 32 patients included in this study had high viral loads of serum HCV-RNA of genotype 1b with chronic hepatitis C. All the patients received a regimen of PEG-IFN plus ribavirin for 48 weeks, and were then divided into two groups: one group (effective group) with undetectable serum HCV-RNA levels at 24 weeks (n = 22) of therapy, the other group (ineffective group) with persistent presence of HCV-RNA in serum at 24 weeks (n = 10). The 2-5AS activity in serum was measured 2, 8 and 12 weeks before initial administration. RESULTS: The 2-5AS response ratio (measured value/measured value of baseline 2-5AS) at 2, 8 and 12 weeks after the administration in the effective group was significantly higher than that in the ineffective group. CONCLUSIONS: These results suggest that the ratio of 2-5AS is closely related to the antiviral effect, and that the measurement of 2-5AS response ratio may be a useful clinical parameter of virological response to PEG-IFN plus ribavirin therapy of chronic hepatitis C.  相似文献   
998.
Autoimmune pancreatitis(AIP) is a distinct form of chronic pancreatitis that is increasingly being reported. The presentation and clinical image findings of AIP sometimes resemble those of several pancreatic malignancies, but the therapeutic strategy differs appreciably. Therefore, accurate diagnosis is necessary for cases of AIP. To date, AIP is classified into two distinct subtypes from the viewpoints of etiology, serum markers, histology, other organ involvements, and frequency of relapse: type 1 is related to Ig G4(lymphoplasmacytic sclerosing pancreatitis) and type 2 is related to a granulocytic epithelial lesion(idiopathic duct-centric chronic pancreatitis). Both types of AIP are characterized by focal or diffuse pancreatic enlargement accompanied with a narrowing of the main pancreatic duct, and both show dramatic responses to corticosteroid. Unlike type 2, type 1 is characteristically associated with increasing levels of serum Ig G4 and positive serum autoantibodies, abundant infiltration of Ig G4-positive plasmacytes, frequent extrapancreatic lesions, and relapse. These findings have led several countries to propose diagnostic criteria for AIP, which consist of essentially similar diagnostic items; however, several differences exist for each country, mainly due to differences in the definition of AIP and the modalities used to diagnose this disease. An attempt to unite the diagnostic criteria worldwide was made with the publication in 2011 of the international consensus diagnostic criteria for AIP, established at the 2010 Congress of the International Association of Pancreatology(IAP).  相似文献   
999.
We measured rituximab concentrations in the cerebrospinal fluid (CSF) in 2 patients with diffuse large B-cell lymphoma in whom central nervous system (CNS) invasion had developed. They received rituximab intravenously following irradiation therapy (patient no.1) or along with chemotherapy (patient no.2). The rituximab concentrations in the CSF were considered to be very low (0.2-0.6 microg/ml), and could not be increased significantly by serial intravenous administrations of rituximab. The lymphoma relapsed in patient no.1, and the combined therapy was not effective in patient no.2. An alternative approach such as intrathecal administration of rituximab could be anticipated as a new therapeutic strategy for CNS lymphoma.  相似文献   
1000.
An extrahepatic portosystemic shunt that has neither liver cirrhosis nor portal hypertension is rare. A 60-year-old Japanese woman who had been suffering chronic liver disease and anemia with mild disorientation was admitted to investigate general fatigue with dizziness and disorientation. The laboratory data revealed mild pancytopenia and liver dysfunction including hyperammoniemia, an increased Indocyanine Green 15-min retention rate, and a decreased Fischer's ratio. Color Doppler ultrasonography, computed tomography, and arterial portography revealed an extrahepatic portosystemic shunt that extended tortuously from the superior mesenteric vein into the inferior vena cava, and decreased blood flow in the main portal vein. Judging from intraoperative measurement of portal pressure and intraoperative portography, shunt ligations were performed at both the efferent portion of shunt from the superior mesenteric vein and the afferent portion of the shunt into the inferior vena cava, and resection of the spleen was also performed. On the postoperative laboratory data, pancytopenia disappeared, and liver function improved. Postoperative abdominal imaging showed increased blood flow in the main portal vein and disappearance of the shunt vessel. Moreover, symptoms present before surgery also disappeared. In conclusion, surgical treatment of extrahepatic portosystemic shunts may result in better postoperative quality of life if it is performed in carefully selected patients.  相似文献   
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