Evidence that genetic deletion of the TNF receptor p60 or p80 inhibits Fas mediated apoptosis in macrophages

Almost 19 members of the tumor necrosis factor (TNF) superfamily have been identified that interact with 29 different receptors. Whether these receptors communicate with each other is not understood. Recently, we have shown that receptor activator of NF-kappaB ligand signaling is modulated by genetic deletion of the TNF receptor. In the current report, we investigated the possibility of a cross-talk between Fas and TNF-alpha signaling pathway in macrophage cell lines derived from wild-type (WT) mice and from mice with genetic deletion of the type 1 TNF receptor (p60(-/-)), the type 2 TNF receptor (p80(-/-)), or both receptors (p60(-/-)p80(-/-)). We found that the macrophages expressing TNF receptors were highly sensitive to apoptosis induced by anti-Fas. The genetic deletion of TNF receptors, however, made the cells resistance to anti-Fas-induced apoptosis. Anti-Fas induced activation of caspase-3 and PARP cleavage in WT cells but not in TNF receptor-deleted cells. This difference was found to be independent of the expression of Fas, Fas-associated protein with death domain (FADD) or TNF receptor-associated death domain (TRADD). We found that anti-Fas induced recruitment of TNFR1 into Fas-complex. We also found that TRADD, which mediates TNF signaling, was constitutively bound to Fas receptor in TNF receptor-deleted cells but not in wild-type cells. Transient transfection of TNFR1 in TNFR1-deleted cells sensitized them to anti-Fas-induced apoptosis. Overall our results demonstrate that Fas signaling is modulated by the TNF receptors and thus provide the evidence of cross-talk between the receptors of two cytokines.     

妥卡尼对豚鼠心室肌细胞钙电流和钾电流的抑制作用

利用酶分散的成年豚鼠心室肌细胞和全细胞电压钳技术,研究了妥卡尼(tocainide)对心室肌细胞钙电流(I_ca)、延迟整流钾电流(I_k)和ATP敏感性钾电流(Ik,ATP)的作用。结果表明,妥卡尼对I_ca和I_k均显示浓度相关的抑制作用,妥卡尼50umol·L^-1对I_ca和I_k的抑制率分别为16%和3%。这可能是妥卡尼有效抑制室上性心动过速和缩短心肌动作电位平台期的重要机制。     

Ovarian stromal luteoma in a patient with endometrial carcinoma

A 65-year-old patient with endometrial adenocarcinoma underwent hysterectomy. Pathological examination of the right ovary revealed a coexisting stromal luteoma. The possible relationship between the two neoplasms as well as the intriguing pathogenesis and controversial nomenclature of ovarian steroid cell tumors are discussed. The incidental discovery of a stromal luteoma in a total hysterectomy specimen removed for endometrial carcinoma raises interesting questions about the perceived innocuous nature of these rare lipid cell tumors.     

The investigation of a recurrence of an AHC virus epidemic at Lucknow: a serosurvey for AHC virus antibodies before and after the epidemic.

An epidemic of acute haemorrhagic conjunctivitis (AHC) recurred at Lucknow during July to September 1975, after a gap of 4 years. Out of the 35 cases investigated thoroughly, 20 Entero-70-like cytopathogenic agents were isolated from the conjunctiva which were neutralized by antisera against AHC virus J670/71 of Japan. Seroconversion was seen in 7 out of 11 paired sera from patients. Serological study was also done on 100 sera collected before the AHC epidemic of 1971, 100 sera after 1971 and 100 sera after 1975 epidemic. There were no neutralizing antibodies in the pre-epidemic period, while 18% of sera after the first epidemic and 32% after the second epidemic showed antibodies. The incidence of antibodies was highest (43%) in children aged below 10 years. Of the children born after the first epidemic, 44% had antibodies. Thus our findings show that the AHC virus appeared for the firt time at Lucknow in 1971 and the almost complete absence of disease in children, and its mildness during second epidemic, may be due to immunity.     

A new heparin fragment decreases liver ischemia-reperfusion injury

<正>To the Editor:Ischemia-reperfusion injury following surgery and transplantation can lead to irreversible multiorgan failure.Intracellular calcium overload is associated to cellular death during ischemiareperfusion.A recently discovered heparin fragment (HF),trisulfated disaccharide (TD),that acts on sodium-calcium exchanger(NCX) decreasing intracellular Ca²⁺,showed effectiveness on protecting hepatocytes from ischemia-reperfusion injury [1],     

MR findings in iatrogenic Gerbode defect

Congenital or acquired communication between left ventricle and right atrium is rare and can be easily overlooked as an eccentric tricuspid regurgitation jet. MRI is the ideal modality for accurate diagnosis, providing details for surgical planning about the location and size of the defect.     

Percutaneous Fetal Atrial Balloon Septoplasty for Simple Transposition of the Great Arteries With an Intact Atrial Septum

We report the first ultrasonographically guided percutaneous balloon atrial septoplasty (BAS), to our knowledge, in a fetus with transposition of the great arteries and an intact ventricular and atrial septum (37 + 2 weeks). After vaginal delivery at 38 weeks, the infant had an elective septostomy (day 1) and an arterial switch procedure (day 7), with an uneventful postoperative course. For centres with experience in fetal cardiac interventions, fetal BAS is a superior management option compared with the alternatives for this high-risk physiology.