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71.
Although exfoliative dermatitis (erythroderma) secondary to malignancy is commonly associated with lymphomas or leukemias, coincident gastrointestinal (GI) malignancy and erythroderma is rare. The authors recently encountered a patient with gallbladder carcinoma presenting as erythroderma. A 77-yr-old Japanese man presented with a 3-mo history of erythematous eruptions with pruritus over almost the entire body. After confirming the diagnosis of erythroderma, asymptomatic gallbladder carcinoma was found. Further investigations detected no malignancies in other organs. An extended cholecystectomy was performed. Histologic examination of resected specimens revealed poorly differentiated adenocarcinoma with negative resection margins. The eruptions with pruritus resolved within 1 wk after the operation. This is the first report, to our knowledge, of coincident biliary malignancy and erythroderma. The experience of the current patient suggests that erythroderma secondary to GI malignancy may resolve spontaneously after curative resection of the tumor.  相似文献   
72.
The recently developed Pig‐a mutation assay is based on flow cytometric enumeration of glycosylphosphatidylinositol (GPI) anchor‐deficient red blood cells caused by a forward mutation in the Pig‐a gene. Because the assay can be conducted in nontransgenic animals and the mutations accumulate with repeat dosing, we believe that the Pig‐a assay could be integrated into repeat‐dose toxicology studies and provides an alternative to transgenic rodent (TGR) mutation assays. The capacity and characteristics of the Pig‐a assay relative to TGR mutation assays, however, are unclear. Here, using transgenic gpt delta mice, we compared the in vivo genotoxicity of single oral doses of N‐ethyl‐N‐nitrosourea (ENU, 40 mg/kg), benzo[a]pyrene (BP, 100 and 200 mg/kg), and 4‐nitroquinoline‐1‐oxide (4NQO, 50 mg/kg) in the Pig‐a (peripheral blood) and gpt (bone marrow and liver) gene mutation assays. Pig‐a assays were conducted at 2, 4, and 7 weeks after the treatment, while gpt assays were conducted on tissues collected at the 7‐week terminal sacrifice. ENU increased both Pig‐a and gpt mutant frequencies (MFs) at all sampling times, and BP increased MFs in both assays but the Pig‐a MFs peaked at 2 weeks and then decreased. Although 4NQO increased gpt MFs in the liver, only weak, nonsignificant increases (two‐ or threefold above control) were detected in the bone marrow in both the Pig‐a and the gpt assay. These findings suggest that further studies are needed to elucidate the kinetics of the Pig‐a mutation assay in order to use it as an alternative to the TGR mutation assay. Environ. Mol. Mutagen. 54:747–754, 2013. © 2013 Wiley Periodicals, Inc.  相似文献   
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74.
Colour patterns in butterflies and moths are crucial traits for adaptation. Previous investigations have highlighted genes responsible for pigmentation (ie yellow and ebony). However, the mechanisms by which these genes are regulated in lepidopteran insects remain poorly understood. To elucidate this, molecular studies involving dipterans have largely analysed the cis‐regulatory regions of pigmentation genes and have revealed cis‐regulatory modularity. Here, we used well‐developed transgenic techniques in Bombyx mori and demonstrated that cis‐regulatory modularity controls tissue‐specific expression of the yellow gene. We first identified which body parts are regulated by the yellow gene via black pigmentation. We then isolated three discrete regulatory elements driving tissue‐specific gene expression in three regions of B. mori larvae. Finally, we found that there is no apparent sequence conservation of cis‐regulatory regions between B. mori and Drosophila melanogaster, and no expression driven by the regulatory regions of one species when introduced into the other species. Therefore, the trans‐regulatory landscapes of the yellow gene differ significantly between the two taxa. The results of this study confirm that lepidopteran species use cis‐regulatory modules to control gene expression related to pigmentation, and represent a powerful cadre of transgenic tools for studying evolutionary developmental mechanisms.  相似文献   
75.
76.
The aim of this study was to investigate the effect of cilostazol, a cAMP phosphodiesterase inhibitor, on carotid artery intima-media thickness (IMT) and on the incidence of cardiovascular events in Japanese subjects with type 2 diabetes. A total of 62 type 2 diabetic subjects were allocated equally to the cilostazol treatment group (n = 31) and the control group (n = 31). Carotid IMT was evaluated before and after treatment using B-mode ultrasonography. After the study period (mean +/- SD: 2.6 +/- 0.17 years), carotid IMT showed a significantly greater increase in the control group than in the cilostazol group (0.12 +/- 0.14 mm vs. 0.04 +/- 0.02 mm, p < 0.05). In the control group, 1 out of 31 patients suffered from symptomatic cerebral infarction and 1 had angina pectoris during the observation period. On the other hand, no subject in the cilostazol group developed cardiovascular events during the study period. At baseline, the diabetic patients given cilostazol had a significantly lower HbA1c level than the control subjects, but the other atherosclerotic risk factors (BMI, blood pressure, and serum lipids) and the duration of diabetes did not differ between the two groups. These results indicate that cilostazol therapy can attenuate the increase of carotid artery IMT in Japanese subjects with type 2 diabetes.  相似文献   
77.
The influence of warm ischemia on calcium mobilization in liver transplantation was investigated. Twenty-four porcine orthotopic liver transplantations were performed by a temporary portal arterialization technique. Swine were divided into three groups according to warm ischemia time; I (0 min,n=9), II (30 min,n=8), and III (60min,n=7). Ionized calcium was measured in arterial and hepatic venous blood, in initial perfusate, and in initial perfused blood. In group I, all the pigs survived, while in group III all succumbed. In group II, four survived and four died. Ionized calcium level in influx showed no differences, but the level in the initial perfusate in group I was significantly higher than that in group III. The level in the initial perfused blood in group I was significantly higher than levels in groups II and III. Retrospective analysis in group II showed that ionized calcium value in the initial perfused blood in the survivors was significantly higher than that in the non-survivors. A substantial amount of ionized calcium accumulated after revascularization in the graft loaded with warm ischemia, and, in group II, significantly more ionized calcium accumulated in the non-survivors.  相似文献   
78.
We studied MDS-associated inhibitory activity, which inhibited colony formation in vitro of granulocyte-macrophage progenitors (CFU-GM). Macrophages obtained from MDS bone marrow mononuclear cells (BM-MNC) when pretreated with granulocyte-macrophage colony stimulating factor (GM-CSF) suppressed the growth of normal CFU-GM. These macrophages were designated as 'MDS-derived inhibitory macrophages'. Media conditioned by MDS-derived inhibitory macrophages (MDS-CM) also suppressed the growth of normal CFU-GM. In the MDS-CM, high levels of prostaglandin E2 (PGE2) and ferritin were found. However, MDS-CM did not contain detectable levels of tumour necrosis factor (TNF) or gamma-interferon (gamma-IFN). Antiserum against human placental ferritin and/or against PGE2 blocked the haemopoietic inhibitory activity to some extent. These results suggest that inhibitory macrophages may be responsible for the suppression of granulopoiesis in patients with MDS and that the suppression may be mediated by soluble factors including PGE2 and ferritin.  相似文献   
79.

Purpose

The purpose of this study was to determine the prevalence of lymphoid hyperplasia in the lower gastrointestinal tract and its role in patients undergoing colonoscopic examinations, particularly focusing on any allergic predisposition.

Methods

A database search performed at the Department of Gastroenterology at Onomichi Municipal Hospital identified seven patients with lymphoid hyperplasia in the large intestine (i.e., cecum, colon, and/or rectum). Data regarding the endoscopic, biological, and pathological examinations performed and the allergic histories for each patient were retrospectively reviewed from the clinical records.

Results

Median age of the patients (four males, three females) was 50 years. Lymphoid hyperplasia was seen in the cecum (n?=?5), ascending colon (n?=?2), and transverse colon (n?=?1). Six patients (85.7 %) had one of the allergic airway diseases: allergic rhinoconjunctivitis for pollen (n?=?3), bronchial asthma (n?=?1), infantile asthma (n?=?1), or allergic bronchitis (n?=?1). Drug allergy (n?=?3) and urticaria (n?=?2) were also found. All seven patients had one or more allergic diseases; however, none had a history of food allergy. Blood tests for allergens revealed that six patients (85.7 %) had positive reactions to inherent allergens, whereas only one patient had a positive reaction to food allergens.

Conclusions

Our results indicate that lymphoid hyperplasia in the large intestine may be associated with allergic airway diseases rather than with food allergies; thus, its presence may be useful to detect patients with underlying airway hyperreactivity.
  相似文献   
80.
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