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61.
Background and Aim: We investigated the antiproliferative effects of interferon‐alpha (IFN‐α) and 5‐fluorouracil (5‐FU) in combination on a hepatocellular carcinoma (HCC) cell line. Method: In the in vitro study, IFN‐α and/or 5‐FU was added to the culture of the poorly differentiated‐type HCC cell line, HAK‐1B, and their antiproliferative effects and additional or synergic effects in combination treatment were examined. In the in vivo study, HAK‐1B cells were transplanted into nude mice and the changes in tumor volume and weight, apoptosis, BrdU and cyclin A positive cells, and artery‐like blood vessels were investigated. Expressions of angiogenesis factors and IFN‐α receptor (IFNAR‐2) were examined in the developed tumors. Results: In vitro growth of HAK‐1B cells was suppressed dose‐dependently to 5‐FU, but the addition of IFN‐α did not induce additional or synergic effects. In vivo growth in terms of tumor diameter and weight was suppressed at most in the IFN‐α + 5‐FU (combination) group, that is, the tumor volume became 29.3% and the tumor weight became 54.7% of the control. In the combination group, numbers of BrdU‐positive S‐phase cells and cyclin A positive cells increased together with the increase in apoptotic cells, but there was no significant relation between the tumor shrinkage effects and angiogenesis factors or artery‐like blood vessels. In the combination group, INFAR‐2 decreased significantly in comparison to the other groups. Conclusion: The synergic growth‐suppression effects in the current in vivo study using the combination treatment are attributable to the enhanced induction of S‐phase arrest and of apoptosis.  相似文献   
62.
hERG(G487R) Channel . Introduction: Mutations of human ether‐à‐go‐go‐related gene (hERG), which encodes a cardiac K+ channel responsible for the acceleration of the repolarizing phase of an action potential and the prevention of premature action potential regeneration, often cause severe arrhythmic disorders. We found a novel missense mutation of hERG that results in a G487R substitution in the S2–S3 loop of the channel subunit [hERG(G487R)] from a family and determined whether this mutant gene could induce an abnormality in channel function. Methods and Results: We made whole‐cell voltage‐clamp recordings from HEK‐293T cells transfected with wild‐type hERG [hERG(WT)], hERG(G487R), or both. We measured hERG channel‐mediated current as the “tail” of a depolarization‐elicited current. The current density of the tail current and its voltage‐ and time‐dependences were not different among all the cell groups. The time‐courses of deactivation, inactivation, and recovery from inactivation and their voltage‐dependences were not different among all the cell groups. Furthermore, we performed immunocytochemical analysis using an anti‐hERG subunit antibody. The ratio of the immunoreactivity of the plasma membrane to that of the cytoplasm was not different between cells transfected with hERG(WT), hERG(G487R), or both. Conclusion: hERG(G487R) can produce functional channels with normal gating kinetics and cell‐surface expression efficiency with or without the aid of hERG(WT). Therefore, neither the heterozygous nor homozygous inheritance of hERG(G487R) is thought to cause severe cardiac disorders. hERG(G487R) would be a candidate for a rare variant or polymorphism of hERG with an amino acid substitution in the unusual region of the channel subunit. (J Cardiovasc Electrophysiol, Vol. 23, pp. 1246–1253, November 2012)  相似文献   
63.
In order to study the process of hepatocellular carcinoma (HCC) development, and to search for a clue to histologic diagnosis of well-differentiated HCC (wd-HCC), interstitial invasion in small HCC was evaluated. The study material consisted of 35 cases of HCC that were smaller than 3 cm that comprised 17 cases of wd-HCC, 18 cases of moderately or poorly differentiated classical HCC (cl-HCC), and 20 cases of large regenerative nodules (LRN). Interstitial invasion was microscopically classified into three patterns: (i) crossing type, in which HCC was invading across fibrous septa of tumour nodules; (ii) longitudinal type, in which tumour cells were growing longitudinally within fibrous septa; and (iii) irregular type, in which the portal area was irregularly invaded by HCC. The crossing type was found in two cases (12%) of wd-HCC and 10 cases (56%) of cl-HCC while the longitudinal type was observed in 16 cases (94%) of wd-HCC and eight cases (44%) of cl-HCC. The irregular type was frequently seen in wd-HCC (15 cases, 88%), and cl-HCC (12 cases, 67%). No interstitial invasion was observed in LRN. Interstitial invasion could be recognized even in the low magnification view of histological specimens, with a detection rate of 59% (10 cases) in wd-HCC and 72% (13 cases) in cl-HCC. These results suggest that evaluation of interstitial invasion is useful in diagnosing wd-HCC independent of cellular atypia. In addition, such invasive growth is revealed to play an important role in destroying original hepatic architecture during its developmental process from the early to advanced stages.  相似文献   
64.
A 43-year-old man underwent living related-donor renal transplantation because of chronic renal failure in 1991. During the transplant period, both donor and recipient were seronegative for hepatitis B surface antigen (HBsAg). The donor was seropositive for antibody to hepatitis B surface antigen (anti-HBs) due to hepatitis B virus (HBV) vaccination. After transplantation, FK506 and methylprednisolone had been administered to the patient as immunosuppressants. In 1993, HBsAg appeared in his serum. His alanine aminotransferase level elevated gradually during 1995 and then in 1996, general fatigue, ascites and jaundice developed. At this time his serum was positive for hepatitis B e antibody, contained more than 100000 Meq/mL HBV-DNA and 100% precore mutant. Despite subsequent intensive therapy, liver dysfunction progressed and this patient died of hepatic failure 2 months following admission. At autopsy, the liver exhibited cholestasis, fibrosis extending from the portal tracts, mild inflammation and hepatocytes with a ground-glass appearance. In addition, HBsAg and hepatitis B core antigens had accumulated in the hepatocytes. Consequently, the final diagnosis was fibrosing cholestatic hepatitis (FCH) due to precore mutant HBV infection contracted after renal transplantation. It is unclear when and where the recipient liver became HBV infected. Nevertheless, after renal transplantation, while receiving immunosuppressive drugs, HBV appeared to have the potential to cause hepatic failure and FCH may have been a fatal complication for the recipient.  相似文献   
65.
The haemodynamic effects of nipradilol, a new non-selective β-adrenoreceptor blocker with vasodilating actions like nitroglycerin, were examined in rats with portal hypertension due to portal vein stenosis. Portal hypertensive rats were divided into five groups receiving infusion of placebo, 3 mg of propranolol, 300, 600 and 1200 μg of nipradilol. At its highest dose, nipradilol achieved a reduction of 34.4 ± 4.4% in heart rate which was similar to that in the propranolol group (36.5 ± 2.4%). Also for other systemic haemodynamic parameters, the nipradilol 1200 μg group exhibited changes not significantly different from those in the propranolol group; mean arterial pressure (- 13 vs - 14%), cardiac index (- 37 vs - 31%) and systemic vascular resistance (+ 29 vs+ 32%). In contrast to the similar changes in the systemic circulation, a 1200 μg dose of nipradilol lowered portal pressure significantly more than propranolol (- 4.3 ± 0.6 vs - 2.9 ± 0.2 mmHg, P≤ 0.05). Nipradilol then reduced portal blood flow by 22% (P≤ 0.05) without a significant change in portocollateral resistance. On the other hand, propranolol not only caused a reduction in portal blood flow of 30% (P≤ 0.01), but also an increase in portocollateral resistance of 21% (P≤ 0.05). The results suggest that nipradilol may ensure a more effective control of portal hypertension than propranolol, presumably via its venodilatory action on portocollateral vessels.  相似文献   
66.
We report a patient undergoing haemodialysis, who developed multiple subcutaneous nodules. Histology showed that the noduies were composed of deposits of crystals in the dermis, with an associated foreign-body reaction. The crystalline deposits were identified as calcium oxalate by histochemical staining, polarizing microscopy, and analytical electron microscopy.  相似文献   
67.
The Sulfurtransferases. Westley, J., Adler, H., Westley, L.and Nishida, C. (1983). Fundam. Appl. Toxicol. 3: 377–381The sulfurtransferases are a group of proteins that catalyzethe formation, interconversion and reactions of compounds containingsulfane sulfur atoms. Serum albumin has properties that implicateit as a major potential sulfur carrier/transferase. The relevanceof the sulfane pool system as a whole to cyanide detoxicationappears clear. The mechanisms of action of the various componentsat the molecular level are still under investigation.  相似文献   
68.
69.
Abstract. An autopsy case of leiomyosarcoma originating in the maxilla is presented. Although repeated light microscopic findings were consistent with a diagnosis of fibrosarcoma, electron microscopic examination revealed myofilaments with dense patches in the spindle-shaped cytoplasm of the tumor cells. It is suggested that “fibrosarcomas” of the oral cavity diagnosed by light microscopy could be leiomyosarcomas.  相似文献   
70.
In an examination of a variety of diseases associated with a peripheral blood eosinophilia it is evident that the eosinophilia is not necessarily accompanied by increased amounts of serum IgE. Tissue eosinophilia occurring with mast cell hyperplasia and usually increased amounts of JgE, indicate atopic allergy. It is considered that the eosinophilic granuloma of soft tissue (Kimura's disease) is an atopic disease and quite different from histiocytosis X.  相似文献   
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