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61.
BACKGROUND: We developed a method for reorganizing the mouse small intestine. In the present study, we investigated whether the reorganized small intestine was morphologically and histochemically differentiated. We also evaluated the reorganized small intestine as an in vitro wound healing model. METHODS: Fetal mouse small intestines were dispersed into single cells, which were then cultured to a high density. Newly formed small intestine-like organs on a membrane filter were observed by light and electron microscopy. Alkaline phosphatase (ALPase) activity of the epithelium was analyzed. To evaluate the reorganized small intestine as an in vitro wound healing model, a scalpel was used to cut the reorganized intestine on a membrane, and the healing process was morphologically and immunohistochemically examined. RESULTS: After 6 days in culture, the surface was almost completely coveed with epithelial cells, and villus-like structures were observed. These epithelial cells formed microvilli, and in parallel with this development, ALPase activity of the microvilli increased (from day 4). Twenty-four hours after the cutting, the wound surface was almost completely covered with undifferentiated epithelial cells. The number of acetylated low-density lipoprotein labeled with 1,1,dioctadecyll,3,3,3,3, tetramethyl-indocarbocyanine perchlorate (DiI-Ac-LDL)-positive macrophages increased after cutting. Platelet-derived growth factor (PDGF)-, basic fibroblast growth factor (bFGF)-, matrix metalloproteinase-1 (MMP-1)-positive cells were detected by immunohistochemical staining. CONCLUSIONS: The reorganized small intestine had a morphologically and histochemically differentiated organoid structure, and was useful as an in vitro model for investigating the process of wound healing.  相似文献   
62.
We describe the case of a 72-year-old asymptomatic man with a cholangiocarcinoma arising from a biliary hamartoma, also referred to as "von Meyenburg's complex". The patient was clinically diagnosed as having a cystadenocarcinoma, but the tumor had already been present as a uniformly low-density area on computed tomography taken four years previously, as revealed by retrospective examination of the computed tomography films that had been taken annually after surgery for pulmonary emphysema. The low-density area had continued to enlarge year after year, and a high-density area was observed to have emerged inside the low-density area on computed tomography. Histopathological examination demonstrated that the high-density area corresponded to the cholangiocarcinoma and the low-density area to a biliary hamartoma. This is the first case in which it was possible to confirm the presence of cholangiocarcinoma inside a biliary hamartoma that had continued to increase in size.  相似文献   
63.
64.
In this study, we compared the impact of health problems (HPs) on everyday activities and depressive symptoms between middle-aged and older adults. We also examined what type and source of social interactions moderate the noxious effects of HPs. Longitudinal analyses of data with 1,802 Japanese community-dwelling adults indicated that HPs were significantly related to (a) an increase in depressive symptoms among middle-aged adults and (b) a decline in everyday activities among older adults. The former was buffered by emotional family support, whereas the latter (b) was buffered by instrumental family support and, surprisingly, by negative interactions with family. In contrast, social interactions with other friends and acquaintances did not show any moderating effect.  相似文献   
65.
Previous studies have found markedly elevated serum concentrations of proinflammatory cytokines in patients with Graves’ disease (GD). We investigated the role of macrophage colony-stimulating factor (M-CSF) in GD. We assayed concentrations of M-CSF in sera from 32 patients with GD (25 untreated; 7 receiving thiamazole therapy). We also studied 32 age-matched healthy subjects as controls. Relationships between serum M-CSF and both thyroid state and serum lipids were examined. Moreover, to examine the effect of thyroid hormone alone on serum M-CSF, T3 was administered orally to normal subjects. Serum concentrations of M-CSF in GD patients who were hyperthyroid were significantly increased compared with GD patients who were euthyroid (P < 0.05) and control subjects (P < 0.0001). Serum M-CSF concentrations correlated closely with T3 levels in patients (= 0.51, < 0.005). Serial measurement of five individual patients revealed that serum concentrations of M-CSF were significantly decreased (P < 0.05), reaching normal control values upon attainment of euthyroidism. Furthermore, oral T3 administered to 15 volunteers for 7 days produced significant increases in serum levels of M-CSF (< 0.05). The close correlation between serum M-CSF and serum thyroid hormone levels suggests that high circulating levels of thyroid hormones may directly or indirectly potentiate the production of M-CSF in patients with GD.  相似文献   
66.
During the epidemic of severe acute respiratory syndrome in 2003, a 27-year- old Japanese woman presented a high fever and acute respiratory distress with pulmonary infiltrates after traveling to a high-risk area. An alternative diagnosis was made as Epstein-Barr virus-associated hemophagocytic syndrome, based on the proliferation of macrophages with hemophagocytosis in the bone marrow and Epstein-Barr viral marker profiles. Virus-associated hemophagocytic syndrome in an international traveler should be included in the differential diagnosis of severe acute respiratory syndrome.  相似文献   
67.
IgG4-related disease (IgG4-RD) is a potentially multiorgan disorder. In this study, clinical and serological features from 132 IgG4-RD patients were compared about organ correlations. Underlying pathologies comprised autoimmune pancreatitis (AIP) in 85 cases, IgG4-related sclerosing cholangitis (IgG4-SC) in 12, IgG4-related sialadenitis (IgG4-SIA) in 56, IgG4-related dacryoadenitis (IgG4-DAC) in 38, IgG4-related lymphadenopathy (IgG4-LYM) in 20, IgG4-related retroperitoneal fibrosis (IgG4-RF) in 19, IgG4-related kidney disease (IgG4-KD) in 6, IgG4-related pseudotumor (IgG4-PT) in 3. Sixty-five patients (49%) had multiple IgG4-RD (two affected organs in 36 patients, three in 19, four in 8, five in 1, and six in 1). Serum IgG4 levels were significantly higher with multiple lesions than with a single lesion (P<0.001). The proportion of association with other IgG4-RD was 42% in AIP, the lowest of all IgG4-RDs. Serum IgG4 level was lower in AIP than in other IgG4-RDs. Frequently associated IgG4-RDs were SIA (25%) and DAC (12%) for AIP; AIP (75%) for IgG4-SC; DAC (57%), AIP (38%) and LYM (27%) for IgG4-SIA; AIP (26%) and LYM (26%) for IgG4-DAC; SIA (75%), DAC (50%) and AIP (45%) for IgG4-LYM; SIA (58%), AIP (42%) and LYM (32%) for IgG4-RF; AIP (100%) and SIA (67%) for IgG4-KID; and DAC (67%) and SIA (67%) for IgG4-PT. Most associated IgG4-RD lesions were diagnosed simultaneously, but IgG4-SIA and IgG4-DAC were sometimes identified before other lesions. About half of IgG4-RD patients had multiple IgG4-RD lesions, and some associations were seen between specific organs.

Graphical Abstract

相似文献   
68.
To determine whether “autoimmune hepatitis type IIb” should be categorized as a subgroup of autoimmune hepatitis, we conducted a clinicopathological study of 25 adult Japanese patients who were positive for anti-liver/kidney microsome-1 (anti-LKM-1) antibody and infected with the hepatitis C virus (HCV). Anti-LKM-1 was determined by indirect immunofluo-rescence and by the double immunodiffusion assays we have developed. Twenty-two patients did not present any unusual symptoms or any associated diseases during the course of their chronic HCV infection. The spectrum of HCV genotypes of these patients did not significantly differ from that of anti-LKM-1-negative Japanese patients with chronic hepatitis C. Histological examination of liver biopsy specimens showed the usual characteristics of chronic hepatitis C and lack of characteristics of autoimmune hepatitis type I. No disease-specific HLA haplotypes were noted, and HLA-DR4, which is detectable in 88.7% of Japanese patients with autoimmune hepatitis type I, was detected in only 50.0% of our group, the same rate as the background frequency. Prednisolone was effective in none of the six patients treated, but interferon was effective in six of ten treated patients (60%). From these results, we conclude that “autoimmune hepatitis type IIb” should not be categorized as autoimmune hepatitis, and that this subgroup is essentially chronic hepatitis C in which an autoantibody has been produced during the course of chronic HCV infection.  相似文献   
69.
70.
A 73-year-old woman was admitted with consciousness disturbance following a fever. Abdominal computed tomography revealed a large liver abscess with which the presence of Desulfovibrio desulfuricans and Escherichia coli was confirmed by thorough blood and abscess content culture. Empiric meropenem treatment was switched to cefoperazone/sulbactam, followed by ampicillin/sulbactam based on susceptibility testing. Desulfovibrio desulfuricans is a common bacterium that rarely causes liver abscess and may be overlooked during co-infection due to overgrowth of the accompanying bacteria. Clinicians should bear Desulfovibrio desulfuricans in mind and select the appropriate antibiotics according to susceptibility testing when anaerobic bacteria are detected in a liver abscess.  相似文献   
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