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71.
We determined whether hyperplastic mucosa adjacent to colon cancer contributes to neoplastic angiogenesis. Surgical specimens of human colon cancer (40 Dukes' stage B and 34 Dukes' stage C) were analyzed by immunohistochemistry for expression of proliferative and angiogenic molecules. The mucosa adjacent to Dukes' stage C tumors (but not Dukes' stage B tumors) had a higher Ki-67 labeling index and a higher expression of epidermal growth factor receptor and transforming growth factor-alpha than distant mucosa. The expression levels of vascular endothelial growth factor, basic fibroblast growth factor, interleukin-8, and the vascular density in the adjacent mucosa were similar to those in the tumor lesions and significantly higher than those in the distant mucosa. The expression of interferon-beta inversely correlated with the level of pro-angiogenic molecules and the vascular density. The injection of metastatic human colon cancer cells and murine colon cancer cells into the cecal wall of mice induced hyperplastic changes in the adjacent mucosa which expressed higher levels of epidermal growth factor receptor, basic fibroblast growth factor, and vascular endothelial growth factor, and lower levels of interferon-beta than did the control mucosa, which directly correlated with the degree of hyperplasia. These data suggest that metastatic human colon cancer cells can induce hyperplasia in the adjacent mucosa, which in turn produces angiogenic molecules that contribute to neoplastic angiogenesis.  相似文献   
72.
Changes in the plasma thrombomodulin (TM) level were examined in endotoxin-infused rabbits. The plasma TM level in normal rabbits was 143.8 +/- 8.4 ng/ml (n = 67) and the molecular weight of the major TM was about 55 kd. Endotoxin (lipopolysaccharide, LPS, E. Coli B8:0127) was intravenously infused. LPS infusion increased the plasma TM level dose-dependently between 0.2 mg/kg and 5 mg/kg. When 5 mg/kg LPS was infused, the plasma TM level started to increase immediately and was 2.3 times higher than the control value within 1 hr. The molecular weight of the major TM was about 75 kd. This rapid increase in TM occurred before the decrease in fibrinogen content and the prolongation of prothrombin time. To examine the effect of circulating leukocytes on the TM increase in endotoxin-infused rabbits, 5 mg/kg LPS was infused into rabbits with leukocytopenia induced by X-ray irradiation. The maximum plasma level of TM was significantly lower than in the untreated rabbits given LPS. These data suggest that the increase in plasma TM is caused by LPS-stimulated leukocyte's prior to hemostaseological changes. It is well known that endothelial cells can be injured by stimulated leukocytes, so this increase in plasma TM probably reflects the deterioration of endothelial cells. This deterioration decreases the ability of endothelial cells to inhibit thrombosis, which would, in turn, contribute to the development of disseminated intravascular coagulation in endotoxin-infused rabbits.  相似文献   
73.
IgG4-related disease is a recently established systemic condition. Tubulointerstitial nephritis is the most common renal manifestation. Glomerular lesions, particularly membranous glomerulonephritis, can develop simultaneously. Some patients present with serological renal dysfunction associated with elevated IgG or IgE levels and hypocomplementemia, while others are incidentally found to have abnormalities in kidneys on imaging. A majority of patients with IgG4-related kidney disease have similar lesions at other anatomical sites, which help us to suspect this condition. Serum IgG4 elevation (>135 mg/dL) is the most, although not entirely, specific marker for the diagnosis. Imaging findings varies from small nodules to bilateral diffuse abnormalities. In addition to the renal parenchyma, the renal pelvis and perirenal adipose tissue can be affected. Histological features include dense lymphoplasmacytic infiltration, storiform or “bird’s eye” fibrosis (highlighted by PAM stain), and IgG4-positive plasma cell infiltration (>10 cells/high-power field and IgG4/IgG-positive cell ratio >40%). Immune complex deposition is detectable in the tubular basement membrane by immunofluorescence and/or electron microscopy. Patients usually respond well to corticosteroids, but highly active diseases may require other immunosuppressive therapies. Further investigations will be required to fully understand pathophysiology underlying this emerging condition.  相似文献   
74.
We present a case of granular cell tumor (GCT) occurring in the esophagus 7 years after operation for bronchial GCT. A 59-year-old Japanese man complained of epigastralgia, and endoscopic examination of the upper digestive tract disclosed a submucosal tumor in the lower esophagus. Histological examination of the endoscopic mucosal resection of the esophageal tumor showed a proliferation of neoplastic cells with an eosinophilic and granular cytoplasm. The cytoplasm of the neoplastic cells was histochemically positive for PAS stain and immunohistochemically positive for S-100. This tumor did not fulfill any of the diagnostic criteria for malignancy at either the macroscopic or microscopic level. I believe that this is the first case of GCT occurring metachronously in the respiratory and digestive tracts. Clinicians and pathologists should bear in mind that GCT may arise metachronously in the respiratory and digestive tracts.  相似文献   
75.

Background

Medial meniscus posterior root tear (MMPRT) has been reported to play a key role in the development of spontaneous osteonecrosis of the knee (SONK) and osteoarthritis (OA) of the knee. However, little is known about the differences in the development of SONK and OA after MMPRT. The purpose of this study was to investigate the factors contributing to the development of these conditions.

Methods

We evaluated the existence of MMPRT and the extent of medial meniscal extrusion in preoperative magnetic resonance images and proximal tibial morphology in radiographs of 45 patients with SONK and 104 patients with OA who underwent knee surgery.

Results

There were no significant differences in age, gender, height, weight, and body mass index between the two groups. The incidence of MMPRT and the mean posterior tibial slope (PTS) were significantly higher in SONK than in OA patients (62.2% versus 34.3%, P = 0.002, and 12.8° versus 10.5°, P < 0.001, respectively). The mean extent of meniscal extrusion was larger in OA than in SONK patients (7.5 mm versus 5.3 mm, P < 0.001). The mean tibial varus angle was 4.8° in SONK and 5.4° in OA, with no significant difference between the two (P = 0.088). Multivariable logistic regression analysis showed that compared with OA, SONK was more closely associated with the existence of MMPRT and had a smaller extent of medial meniscus extrusion and higher PTS.

Conclusion

MMRPT and higher PTS were more closely associated with the development of SONK than with that of OA.  相似文献   
76.

Purpose

The aim of this study was to evaluate anatomically the relationship between bone and muscles by detailed observation of the bone shape and the structure of muscles to facilitate an understanding of the function of the muscles involved in jaw movement.

Methods

36 specimens of 24 Japanese cadavers were examined. The insertion areas were marked using a radiopaque marker and examined by micro-computed tomography. For morphological observation, we used 101 condylar processes. In addition, we made histological sections in some specimens to observe the detailed attachments of the muscle.

Results

Based on the micro-CT images and dissection findings, the lateral pterygoid muscle was found to be most frequently inserted into the anterior impression and attached to the medial impression of the process. According to the histological observations, the lateral pterygoid muscle mainly inserted to the condylar process. The micro-CT images indicated that the obvious bony ridge was lateral to the pterygoid fovea on the condylar process in all specimens. The midmedial muscle bundle of the temporalis was attached to the ridge. Based on the morphological observations, the ridge was situated on the lateral area of the condylar process.

Conclusions

Since dysfunction of the temporomandibular joint is likely closely related to both the lateral pterygoid muscle and also the temporalis, further studies are necessary to evaluate the function of these muscles and consider jaw movement.
  相似文献   
77.
The calpains, a family of calcium-dependent cysteine proteinases, and calpastatin, their endogenous inhibitor protein, are involved in the proteolysis of amyloid precursor protein, which is thought to be abnormal in patients with Alzheimer's disease (AD). Specific inhibitors of calpains attenuate amyloid beta peptide-induced neuronal death. We hypothesized that some AD patients have functionally deficient mutation(s) of the CAST gene encoding calpastatin, and we screened 40 Japanese patients with AD for mutations in the coding region of CAST. Nine polymorphisms, -82A/G, IVS7-96A/G, 669A/G, 1223C/G (Ser408Cys), IVS20-10C/T, IVS21-65G/A, IVS22+31T/C, IVS24+38Ins/DelA, and IVS25-32A/G, were identified. The 669A allele causes skipping of exon 11, leading to the loss of 13 residues. Comparisons between 101 patients and 90 controls revealed no significant association between CAST polymorphisms and risk for AD, indicating that genomic variations of CAST are not likely to be substantially involved in the etiology of AD.  相似文献   
78.
Adipocyte-derived leucine aminopeptidase (ALAP) inactivates angiotensin II and/or generates bradykinin in the kidney, suggesting a possible role for ALAP in the regulation of blood pressure. We considered the hypothesis that genomic variants of the ALAP gene are associated with hypertension or individual variations in blood pressure. We screened for mutations in the ALAP gene in 48 unrelated Japanese individuals and identified 33 polymorphisms including 15 novel polymorphisms. We then performed a two-stage analysis. In the first stage, the eight missense polymorphisms were evaluated for associations with blood pressure in 96 apparently healthy individuals. In the second stage, only the most promising polymorphisms were evaluated for association with essential hypertension in 143 hypertensive and 348 normotensive subjects. Among the eight missense polymorphisms, the Ile276Met and Lys528Arg polymorphisms showed significant association with blood pressure. Subsequent analysis confirmed association between the Lys528Arg polymorphism and essential hypertension. The estimated odds ratio for essential hypertension was 2.3 for presence of the Arg allele at codon 528, in comparison with presence of the Lys/Lys genotype (P = 0.004). These findings support involvement of ALAP in the regulation of blood pressure.  相似文献   
79.
Camostat mesilate (CM), an oral protease inhibitor, has been used clinically for the treatment of chronic pancreatitis in Japan. However, the mechanism by which it operates has not been fully understood. Our aim was to evaluate the therapeutic efficacy of CM in the experimental pancreatic fibrosis model induced by dibutyltin dichloride (DBTC), and we also determined the effect of CM on isolated monocytes and panceatic stellate cells (PSCs). In vivo, chronic pancreatitis was induced in male Lewis rats by single administration of 7 mg/kg DBTC and a special diet containing 1 mg/g CM was fed to the DBTC+CM-treated group from day 7, while the DBTC-treated group rats were fed a standard diet. At days 0, 7, 14 and 28, the severity of pancreatitis and fibrosis was examined histologically and enzymologically in both groups. In vitro, monocytes were isolated from the spleen of a Lewis rat, and activated with lipopolysaccharide stimulation. Thereafter, the effect of CM on monocyte chemoattractant protein-1 (MCP-1) and tumor necrosis factor-alpha (TNF-alpha) production from monocytes was examined. Subsequently, cultured rat PSCs were exposed to CM and tested to see whether their proliferation, MCP-1 production and procollagen alpha1 messenger RNA expression was influenced by CM. In vivo, the oral administration of CM inhibited inflammation, cytokines expression and fibrosis in the pancreas. The in vitro study revealed that CM inhibited both MCP-1 and TNF-alpha production from monocytes, and proliferation and MCP-1 production from PSCs. However, procollagen alpha1 expression in PSCs was not influenced by CM. These results suggest that CM attenuated DBTC-induced rat pancreatic fibrosis via inhibition of monocytes and PSCs activity.  相似文献   
80.
Restrictive cardiomyopathy (RCM) is characterized by irreversible diastolic dysfunction with preserved systolic function. The aim of this study was to investigate the presence of impaired ventricular contractility even in the presence of normal ejection fraction (EF) in children with RCM. Longitudinal Doppler tissue velocities were obtained from apical 4-chamber view at three locations—the left-ventricular (LV) lateral wall, the septum, and the right ventricle—in 8 children age 3–17 years old with RCM who had LV EF >55%. Peak systolic velocity (S′), acceleration during isovolumic contraction (IVA), and myocardial performance index (MPI) were measured. Data from the RCM group were compared with those from 24 age- and sex-matched controls. Both S′ and IVA were markedly lower at the septum (S′ 6.2 ± 1.7 vs. 9.2 ± 1.6, P < 0.001; IVA 1.8 ± 0.5 vs. 3.9 ± 1.5, P < 0.001). MPI, a measure of both diastolic and systolic function, was statistically significantly greater in the RCM group at all 3 locations (P < 0.005). S′ and IVA identify global subclinical systolic dysfunction in RCM with normal EF. These findings suggest that pre-ejection abnormality and subclinical systolic dysfunction coexist with diastolic dysfunction in children with RCM.  相似文献   
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