人类淋巴母细胞TK6检测环磷酰胺诱发微核及TK基因突变的体外实验研究

目的 建立TK6细胞检测环境诱变剂诱发微核及TK基因突变的实验方法。方法 用诱变剂环磷酰胺(CP)体外染毒TK6细胞4h后检测细胞毒性,微核及kt位点突变频率。结果 CP处理导致TK6细胞的相对存活率下降,细胞微核率及TK基因突变频率明显上升,并均有剂量——反应关系。最高浓度组(4．0μg／ml)的细胞微核率及TK基因突变频率分别是对照组的8、8和15．7倍。CP诱发tk位点两种不同表型的突变细胞集落,即正常生长突变体集落及缓慢生长突变体集落,并以后者为主。结论 CP可以诱发TK6细胞微核及TK基因突变,揭示CP可能是一种断裂剂。TK6细胞可用于评估环境化学物细胞水平遗传改变及TK基因突变。     

Comparison of specificity between IgG,IgE and T cells to three casein components: Implication for the role of circulating allergenspecific T cells in food allergy

In order to investigate the role of food antigen-specific T cells circulating in the blood of patients with food allergy, we compared T cell response to three casein components (αs-, β- and, K-casein) with specificities of IgG and IgE binding to the casein components in four milk-allergic patients (P1-4) with atopic dermatitis. In all patients, the binding activities of IgG antibodies to αs-casein were most dominant, followed by those to β- and to K-casein. The major component of casein bound by IgE antibodies was αs-casein in P1 and P3, K-casein in P2, and αs-casein as well as K-casein in P4; the order of casein components bound by IgE antibodies was different from that by IgG antibodies. Proliferative responses of peripheral blood mononuclear cells (PBMC) to casein components were so low that the dominance of casein recognition could not be clearly demonstrated. However, short-term T cell lines that specifically respond to casein were successfully established from PBMC of the four patients and the proliferative responses of the T cell lines to the three components of casein were in accord with the IgE antibody specificity to casein components but not with that of IgG antibody specificity. When taken together, these results indicate that casein-specific T cells circulating in the blood are involved in or reflect an allergic reaction against casein.     

Daily melatonin intake resets circadian rhythms of a sighted man with non-24-hour sleep-wake syndrome who lacks the nocturnal melatonin rise

Abstract Effects of daily melatonin intake on the circadian rhythms of sleep and wakefulness, rectal temperature and plasma cortisol were examined in a sighted man who had suffered from the non-24-hour sleep-wake syndrome. The subject lacked the nocturnal melatonin rise in plasma, but showed robust circadian rhythms in rectal temperature and plasma cortisol. The sleep-wake rhythm free-ran with a period longer than 24 hours. Daily melatonin intake at 21:00 h concentrated sleep episodes in the nocturnal period (24:00–8:00 h), and increased the length of the episodes. A single oral dose (3 mg) of melatonin increased plasma melatonin levels to about 1300 pg/mL within one hour and remained at pharmacological levels for approximately 6 hours. The trough of rectal temperature and the circadian rise of plasma cortisol were fixed to the early morning. A higher dose of melatonin (6 mg) did not improve the general feature. After the cessation of melatonin intake, the sleep-wake rhythm began to free-run together with the circadian rhythms in rectal temperature and plasma cortisol. It is concluded that daily intake of melatonin at early night time resets the circadian rhythms in a sighted man who lacked the nocturnal melatonin rise and showed free-running circadian rhythms in routine life.     

Sarcoidosis during infliximab therapy for Crohn’s disease

Tumor necrosis factor‐α (TNF‐α) antagonists are effective for inflammatory diseases, such as Crohn’s disease, rheumatoid arthritis (RA) and psoriasis. Although TNF‐α antagonists are also useful for sarcoidosis, paradoxical occurrence of sarcoidosis or sarcoidal reaction may be observed. We report a Crohn’s disease patient, who developed sarcoidosis during infliximab therapy. A 35‐year‐old man had been receiving infliximab for 7 months for Crohn’s disease. He developed cough and fever, accompanied by an infiltrated erythematous plaque on his right knee. The chest radiography, skin biopsy and laboratory findings were all consistent with sarcoidosis.     

Oestrogen receptor‐β1 but not oestrogen receptor‐βcx is of prognostic value in apocrine carcinoma of the breast

Apocrine carcinoma of the breast, which frequently expresses oestrogen receptor‐β (ER‐β) in the absence of ER‐α and only infrequently is treated endocrinologically, gives an opportunity to investigate the clinicopathological role of ER‐β in breast cancer independent of ER‐α expression or tamoxifen treatment. Several isotypes of ER‐β, ER‐β1–5 etc., have been identified thus far; however, the clinicopathological importance of each ER‐β isotype in breast cancer is still uncertain. Here we aimed to clarify the clinicopathological importance of ER‐β1 and ER‐βcx (ER‐β2) in apocrine carcinomas, immunohistochemically examining expressions of ER‐β1 and ER‐βcx in 47 apocrine carcinomas. Positivity for ER‐β1 and ER‐βcx was observed in 41 (87%) and 18 (38%) of 47 cases, respectively. ER‐β1 positivity was related to smaller tumor size (P=0.0359), lower histological grade (P=0.0322), and higher disease‐free survival (P<0.0001), whereas ER‐βcx status was related to none of these parameters. ER‐β1 positivity was also associated with favorable clinical outcome in 24 so‐called triple‐negative (ER‐α‐negative/PR‐negative/HER2‐negative) apocrine carcinomas. ER‐β1 itself, independent of ER‐α expression and tamoxifen treatment, seems to have a tumor‐suppressive effect, at least in apocrine carcinomas. Further study of ER‐β1 is desired to optimize breast cancer treatment.     

Gender differences in self-evaluated sleep quality and activity of middle-aged and aged subjects

Abstract In order to investigate the gender difference of sleep and activity in middle-aged and aged individuals, home-based sleep was self-evaluated for sleep quality and activity for 5 nights in 20 healthy adults (50–76 years old; 11 women, nine men). There was no significant gender difference for subjective sleep quality. However, the activity level and movement index at night were significantly higher in men than in women, and the activity level during the day was significantly lower in men than in women. The objective sleep quality of men was significantly worse than that of women, however, subjective sleep quality does not differ.     

Depressed Type Mucosal Cancer of Large Intestine with Converging Mucosal Folds —Report of a Case—

Abstract: A case of depressed type mucosal cancer of the large intestine with converging mucosal folds is discussed. A 71-year-old female was admitted to our hospital with melena. A total colonoscopy revealed a type IIa + IIc lesion measuring 1. 5cm in diameter with converging mucosal folds in the transverse colon. An endoscopic biopsy revealed an adenocarcinoma. A diagnosis of submucosal carcinoma was made and a partial colectomy was performed. The resected specimen showed a type IIc + IIa cancer. Histologically, a well differentiated adenocarcinoma which was limited to the mucosa in association with fibrosis in the submucosa was revealed. The submucosal fibrosis was thought to be a cause of the converging mucosal folds.     

Basal Cell Epithelioma of the Penis: A Case Report

A 65-year-old man had a tumor with a small ulcer on the foreskinof his penis. A local excision was performed. Histological examinationof the specimen revealed superficial basal cell epithelioma.Basal cell epithelioma is a common tumor of the skin, but israrely found on the penis. Only 11 cases have been reportedin the European and American literature. Basal cell epitheliomaswere formerly called basal cell carcinomas and were treatedas true carcinomas. However, recently they have been treatedas benign tumors because of their good prognosis and rare metastasis.     

Diminished interferon-gamma (IFN-γ) production by bacterial antigen-specific T cells in atopic patients

In this study, we established and studied cytokine production of T cell lines (TCL) specific to either a purified protein derivative of Mycobacterium tuberculosis (PPD) or Dermatophagoides farinae (Df) from atopic patients and non-atopic healthy subjects. IFN-γ was detected in the culture supernatants of all of 36 PPD-specific TCL established from healthy controls, whereas only 24 of 38 PPD-specific TCL from patients produced IFN-γ. Furthermore, the amounts of IFN-γ produced by PPD-specific TCL from patients were significantly lower than those from healthy controls. No IL-4 was detected in any PPD-specific TCL from either healthy controls or atopic patients. The amounts of IL-4 production from Df-specific TCL from atopic patients were much higher than from healthy controls, while few TCL produced IFN-γ. These results suggest that the skewing to the Th2-type T cell response in atopic patients is a response not only to allergens, but also to bacterial antigens, compared with non-atopic subjects. Activation of PPD-specific TCL from patients with calcium ionophore A23187 plus phorbol myristate acetate resulted in much higher IFN-γ production than in TCL established from healthy controls, indicating that the low production of IFN-γ by PPD-specific T cells from atopic patients is not due to an intrinsic T cell defect but to some regulatory mechanisms.