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21.
Zhao HF  Ito T  Gibo J  Kawabe K  Oono T  Kaku T  Arita Y  Zhao QW  Usui M  Egashira K  Nawata H 《Gut》2005,54(12):1759-1767
BACKGROUND: Monocyte chemoattractant protein 1 (MCP-1) is a member of the C-C chemokine family and exerts strong chemoattractant activity in monocytes, macrophages, and lymphocytes. Rat pancreatic fibrosis induced by dibutyltin dichloride (DBTC) is considered to be an appropriate chronic pancreatitis model histologically and enzymatically, as has demonstrated in a previous study. AIM: We examined the effect of human dominant negative inhibitor of MCP-1 (mutant MCP-1) on progression of chronic pancreatitis induced by DBTC in a rat model. METHODS: We used the experimental model of chronic pancreatitis induced by DBTC in rats. Mutant MCP-1 or empty plasmid at a dose of 50 microg/body weight was administrated into rat thigh muscles on days 4, 11, and 18 after administration of DBTC. On days 14 and 28, we evaluated the effect of mutant MCP-1 morphologically and biochemically. RESULTS: The mutant MCP-1 treated group inhibited early pancreatic inflammation and later pancreatic fibrosis histologically, and showed a decrease in serum MCP-1 concentration, intrapancreatic hydroxyproline, alpha-smooth muscle actin, and an increase in intrapancreatic amylase and protein content compared with the empty plasmid treated group. The mutant MCP-1 group also inhibited intrapancreatic mRNA expression of cytokines and chemokines. CONCLUSIONS: : Our findings suggest that monocyte/macrophage recruitment and the systemic MCP-1 signal pathway contribute to progression of chronic pancreatitis, and that blockade of MCP-1 may suppress the development of pancreatic fibrosis.  相似文献   
22.
STUDY OBJECTIVES: Malignant and tuberculous pleurisies are two major causes of lymphocyte-dominant pleurisy. Several studies have already reported that tuberculous pleurisy is a T-helper type 1(Th1)-dominant disease. In this study, we sought to examine the Th1/T-helper type 2 (Th2) balance, especially focusing on the polarizing status of T-cells to Th1/Th2 in malignant pleural effusions by measuring cytokines in pleural effusions and by evaluating the polarizing status of T-cells on the point of stimulation with interleukin (IL)-12 and/or IL-18. Furthermore, we evaluated inhibitors of interferon (IFN)-gamma production in effusions to rule out the possibility of direct inhibition of T-cell polarization. PATIENTS: Effusion samples were collected from 19 patients with malignant pleurisy caused by lung cancer and from 7 patients with tuberculous pleurisy. MEASUREMENTS: Concentrations of pleural fluid IFN-gamma, IL-12, and IL-4 were measured. IFN-gamma production of T-cells enriched from malignant pleural effusions in the presence of IL-12 and/or IL-18 was also examined. We further compared the inhibitory activity of malignant pleural effusions against IFN-gamma production and analyzed the expression of T-cell immunoglobulin mucin, mucin domain (Tim-3), a Th1-specific molecule in pleural fluid T-cells. RESULTS: Although malignant pleural effusions showed low levels of Th1 and Th2 cytokines and ratios of IFN-gamma and IL-12 to IL-4 were low, isolated T-cells produced a significant level of IFN-gamma in the presence of IL-12 and IL-18. Soluble factors were not found to inhibit IFN-gamma production in malignant pleural effusions. In tuberculous pleural effusion, ratios of IFN-gamma and IL-12 to IL-4 were significantly higher, and T-cells showed the expression of Tim-3 messenger RNA. CONCLUSIONS: We confirmed that T-cells in the malignant pleural effusions are mainly na?ve or not definitely polarized to Th1. Moreover, malignant tumor does not actively distort the cytokine condition through production of soluble inhibitors within effusions. The present study indicates that antitumor immunity may be enhanced by restored IFN-gamma activity through combination of IL-12 and IL-18, and that it will lead to new therapies for malignant effusion.  相似文献   
23.
BACKGROUND & AIMS: Percutaneous radiofrequency ablation is a recently introduced treatment for hepatocellular carcinoma, whereas ethanol injection is now a standard therapy. We compared their long-term outcomes. METHODS: Two hundred thirty-two patients with hepatocellular carcinoma who had 3 or fewer lesions, each 3 cm or less in diameter, and liver function of Child-Pugh class A or B were entered onto a randomized controlled trial. The primary end point was survival, and the secondary end points were overall recurrence and local tumor progression. RESULTS: One hundred eighteen patients were assigned to radiofrequency ablation and 114 to ethanol injection. The number of treatment sessions was smaller (2.1 times vs 6.4 times, respectively, P < .0001) and the length of hospitalization was shorter (10.8 days vs 26.1 days, respectively, P < .0001) in radiofrequency ablation than in ethanol injection. Four-year survival rate was 74% (95% CI: 65%-84%) in radiofrequency ablation and 57% (95% CI: 45%-71%) in ethanol injection. Radiofrequency ablation had a 46% smaller risk of death (adjusted relative risk, 0.54 [95% CI: 0.33-0.89], P = .02), a 43% smaller risk of overall recurrence (adjusted relative risk 0.57 [95% CI: 0.41-0.80], P = .0009), and an 88% smaller risk of local tumor progression (relative risk, 0.12 [95% CI: 0.03-0.55], P = .006) than ethanol injection. The incidence of adverse events was not different between the 2 therapies. CONCLUSIONS: Judging from higher survival but similar adverse events, radiofrequency ablation is superior to ethanol injection for small hepatocellular carcinoma.  相似文献   
24.
Amebiasis is a common parasitic infectious disease in developing countries. In developed countries, it is occasionally encountered in travelers to the tropics and in homosexual males. During the past eight years, we detected four cases of amebic colitis among 5,193 subjects who underwent colonoscopy because of positive fecal occult blood test results in a mass screening. All four cases did not have any abdominal symptoms. Ulcerative lesions were observed only in the cecum and ascending colon; another portion of the colon and rectum appeared normal. We may encounter amebic colitis during colonoscopic examination even in subjects who are asymptomatic.  相似文献   
25.
Although Helicobacter pylori is classified as a definite carcinogen, the mechanism underlying gastric carcinogenesis is not yet clear. We previously have shown that H. pylori activates an antiapoptotic gene, the cellular inhibitor of apoptosis protein 2 (c-IAP2), the underlying mechanism of which was investigated in the present study. cDNA array and real-time PCR analyses indicated that H. pylori showed a stimulatory effect on the expression of c-IAP2. Isogenic mutant strains with impaired cag pathogenicity island (cagPAI) expression showed weaker induction. Analyses that used the in situ terminal deoxynucleotide transferase-mediated dUTP nick end-labeling method indicated suppression of antiapoptosis by the antisense c-IAP2 oligonucleotide. Reporter assays with deletion and mutation constructs for the c-IAP2 promoter showed that nuclear factor-kappaB (NF-kappaB) binding sites are indispensable for transactivation. Super-repressor IkappaBalpha or NF-kappaB inhibitor reduced c-IAP2 transactivation by H. pylori, and exogenous expression of c-IAP2 inhibited apoptosis seen with H. pylori. In conclusion, H. pylori induces antiapoptosis through c-IAP2 transactivation following cagPAI-dependent NF-kappaB activation. The interaction of these stimuli may play a role in gastric carcinogenesis.  相似文献   
26.
Salivary glands repair and regenerate following various types of injuries and surgical procedures. However, the tissue responses induced in the contralateral glands have yet to be elucidated in detail. Hsp27, a member of the heat-shock protein (Hsp) family, is strongly expressed in physiological environments, particularly during development. Hsp27 was previously shown to play a role in the regulation of acinar cell proliferation and differentiation in the rat submandibular gland.The present study performed the following surgical treatments on the right submandibular glands of adult rats: 1) duct ligation followed by unligation after one week; 2) partial sialoadenectomy; and 3) total sialoadenectomy. Immunohistochemistry for Hsp27 and Ki67 was performed in the experimental and normal contralateral glands, and localization was histologically and morphometrically analyzed.The results obtained revealed the localization of Hsp27 to the intercalated duct in the submandibular glands of non-treated rats. The expression of Hsp27 was strongly induced in both the uninjured contralateral control glands as well as treated glands of experimental rats regardless of the surgical procedure performed. The number of Hsp27-immunopositive cells increased rapidly following surgery, and subsequently returned to the same level as that in non-treated rats after 4 weeks. However, no marked changes were observed in the number of Ki67-immunopositive proliferating cells. Therefore, the change in the number of Hsp27-immunopositive cells may have contributed to compensatory hypertrophy. The results of the present study indicate that the expression of Hsp27 in the intercalated duct in the submandibular gland may play a role in the differentiation of acinar cells.  相似文献   
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A case of acute Wernicke's encephalopathy induced by thiamine deficiency due to malnutrition subsequent to chemoradiotherapy for tongue cancer is presented. A 63-year-old male patient had severe oral mucositis and mental stress in a long-term hospitalization for chemoradiotherapy of tongue cancer. After discharge from hospital, he had alcoholism and malnutrition. Three months later, disturbance of consciousness and ataxia followed by memory disturbance appeared. Laboratory examination revealed low serum level of thiamine. The symptoms, laboratory data, and magnetic resonance imaging suggested acute Wernicke's encephalopathy. The patient was intravenously administered thiamine and received nutritional control, thereby the symptoms were improved.  相似文献   
29.
Hypoparathyroidism is a disease of chronic hypocalcemia and hyperphosphatemia due to a deficiency of parathyroid hormone (PTH). PTH and analogs of the hormone are of interest as potential therapies. Accordingly, we examined the pharmacological properties of a long‐acting PTH analog, [Ala1,3,12,18,22, Gln10,Arg11,Trp14,Lys26]‐PTH(1‐14)/PTHrP(15‐36) (LA–PTH) in thyroparathyroidectomized (TPTX) rats, a model of HP, as well as in normal monkeys. In TPTX rats, a single intravenous administration of LA‐PTH at a dose of 0.9 nmol/kg increased serum calcium (sCa) and decreased serum phosphate (sPi) to near‐normal levels for longer than 48 hours, whereas PTH(1‐34) and PTH(1‐84), each injected at a dose 80‐fold higher than that used for LA‐PTH, increased sCa and decreased sPi only modestly and transiently (<6 hours). LA‐PTH also exhibited enhanced and prolonged efficacy versus PTH(1‐34) and PTH(1‐84) for elevating sCa when administered subcutaneously (s.c.) into monkeys. Daily s.c. administration of LA‐PTH (1.8 nmol/kg) into TPTX rats for 28 days elevated sCa to near normal levels without causing hypercalciuria or increasing bone resorption markers, a desirable goal in the treatment of hypoparathyroidism. The results are supportive of further study of long‐acting PTH analogs as potential therapies for patients with hypoparathyroidism. © 2016 American Society for Bone and Mineral Research.  相似文献   
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