Modulation of auditory cortex unit activity during the performance of a conditioned response

Single-unit activity in primary auditory cortex was studied in unanesthetized, paralyzed cats during the performance of a classical conditioning task. The conditioned stimulus was a 0.5-s white noise (WN) burst paired with tail shock delivered 4.5 s later. Cats habituated to WN without shock served as controls. Overlayed on these tasks was a continuous background of 1/s, behaviorally irrelevant, 100-ms duration tone bursts set to the best frequency and optimal intensity for the particular unit being studied. Spontaneous activity and tone responses following WN were compared with the respective activity preceding WN. The spontaneous or evoked activity of 75% of the cells recorded in the trained animals changed significantly after WN, whereas the activity of 28% of the cells recorded in habituated animals changed. Augmentation and suppression of both spontaneous and evoked activity were found. These results have implications for the encoding of acoustic stimuli in terms of the modulation of lemniscal sensory system activity.     

Cholesteryl-hemisuccinate-induced apoptosis of promyelocytic leukemia HL-60 cells through a cyclosporin A-insensitive mechanism

We reported previously that alpha-tocopheryl-succinate (VES) induced apoptosis of cultured human promyelocytic leukemia cells (HL-60) (Free Radic Res 2000;33:407-18). We have now studied the effect of cholesteryl-hemisuccinate (CS) on the fate of HL-60 cells to clarify whether CS has an effect similar to that of VES. CS inhibited the growth of HL-60 cells without differentiation to granulocytes and induced DNA fragmentation and ladder formation. CS inhibited the phosphorylation of pleckstrin homology domain-containing protein kinase B (Akt) and initiated the activation of a caspase cascade. CS triggered the reaction leading to the cleavage of Bid and also released cytochrome c (Cyt. c) from mitochondria. In addition, CS induced mitochondrial membrane depolarization and translocation of Bax to mitochondria in HL-60 cells. However, CS did not induce an increase in the concentration of intracellular calcium ions in HL-60 cells. The membrane depolarization, Cyt. c release, and DNA fragmentation were inhibited by z-VAD-fluoromethylketone (z-VAD-fmk), a pan-caspase inhibitor, but not by cyclosporin A, an inhibitor of membrane permeability transition. These results suggested that CS-induced apoptosis of HL-60 cells might be caused by inhibiting Akt phosphorylation following cleavage of Bid through caspase-8 activation and subsequently via an Apaf complex-caspase cascade pathway.     

氧化苦参碱-甘珀酸钠复合物的制备及其药理活性初探

目的研究氧化苦参碱-甘珀酸钠复合物的制备方法及其药理活性。方法分别配制氧化苦参碱和甘珀酸钠溶液，将两种溶液按比例混合，分离提纯后得到复合物样品。采用紫外分光光度法确定形成常数，用X射线粉末衍射，红外光谱和核磁来表征该复合物。将制得的药物测其急性毒性，采用CCl4制备小鼠急性肝损伤模型，检测经不同比例氧化苦参碱-甘珀酸钠复合物干预后小鼠血清天冬氨酸转氨酶（AST）、丙氨酸转氨酶（ALT）。结累氧化苦参碱一甘珀酸钠可形成1；1的复合物}1；1、2；1比例形成的复合物的急性毒性均比其前体药物甘珀酸钠、氧化苦参碱低}与CCI．模型组比较，经氧化苦参碱一甘珀酸钠1；1、2；1复合物处理的小鼠血清AST、ALT水平较低。结论氧化苦参碱与甘珀酸钠不同比例复合物的毒性均比其前体药物低；对小鼠急性CCl4肝损伤有保护作用。     

Right Ventricular Function Evolution With Pregnancy in Repaired Tetralogy of Fallot

This case illustrates the evolution of right ventricular (RV) 3-dimensional (3D) area strain during pregnancy in a patient with repaired Tetralogy of Fallot. The report highlights impairment in RV function with pregnancy, suggesting the importance of prepregnancy RV systolic function assessment, especially using 3D echocardiography.     

The set of variable- contrast visual acuitycharts and its clinical application

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Non-radioisotope method for diagnosing photosensitive genodermatoses and a new marker for xeroderma pigmentosum variant

Xeroderma pigmentosum (XP) is an autosomal recessive disorder characterized by photo-induced deterioration of the skin, which often leads to the early development of skin cancers. To diagnose patients with XP and the related disorder Cockayne syndrome (CS), our laboratory has established a simple autoradiographic method that examines three cellular markers of DNA repair: unscheduled DNA synthesis (UDS), recovery of RNA synthesis (RRS) and recovery of replicative DNA synthesis (RDS). However, it is very laborious to measure the three markers using tritiated thymidine or uridine; therefore, we developed a non-isotope method for diagnosing XP and CS. Fibroblasts from the patient were labeled with bromodeoxyuridine (BrdU) instead of tritiated thymidine to measure UDS and RDS, or were labeled with bromouridine (BrU) instead of tritiated uridine to measure RRS. Incorporated BrdU or BrU could be detected using the immunofluorescence method. Moreover, we discovered a new useful marker for XP variant based on checkpoint activity. The non-radioisotope method and the new marker described here comprise an easy way to diagnose XP and CS.     

葛根素缓释复合骨架片理化性质的研究

目的利用甲壳胺 海藻酸钠的聚合物作为新型缓控释制剂的复合骨架材料 ,并对其性质及影响因素进行研究。方法利用天然高分子材料甲壳胺 (CS) (阳离子型 )与海藻酸钠 (AL) (阴离子型 )模拟在体内条件下形成聚电解质复合物。通过DTA及IR图谱的峰值变化证明这种复合物确实存在 ,形成的关键是控制好两种电解质的比例。结果当WCS∶WAL=2∶3时 ,反应最完全。利用制成的聚电解质复合物 ,制备葛根素缓释复合骨架片 ,缓释效果符合中国药典规定。结论甲壳胺 海藻酸钠形成的复合物可以做缓、控释制剂的骨架材料。     

A Randomized Trial Comparing Imipenem/Cilastatine Alone with Latamoxef Plus Tobramycin in Febrile Neutropenic Patients with Lung Cancer

We conducted a randomized trial to compare the efficacy of imipenem/cilastatine(IPM/CS) monotherapy with thatof a combination of latamoxef(LMOX) and tobramycin (TOB) in the initial management of feverand neutropenia in patients with lung cancer. Leukocytopenicfebrile patients(<3,000 leukocytes perµl; temperature>38°C) with lung cancer given induction therapy wererandomly assigned to receive intravenous treatment with either1g IPM/CS twice daily or 2g LMOX plus 90 mg TOB twice daily.A total 101 febrile episodes were studied. Fifty-one episodeswere treated with IPM/CS and 50 with LMOX+TOB. Fifty-nine ofthe febrile episodes were bacteriologically confirmed, whilean organism could not be isolated despite the presence of obviousclinical infection in the remaining 42. The response rate was82% with IPM/CS and 80percent; with combination therapy. Thisdifference was not statistically significant. The response rateregarding gram-negative infections was 10 out of 14 (71%) inthe IPM/CS group and seven out of 12(58%) in the LMOX+TOB group.This differnce was also not significant (P=0.484). The responserate in severely neutropenic patients (neutrophils <100/µl)was low (P=0.078). Three patients in the IPM/CS group were withdrawnfrom the study due to skin rash and vomiting. Therapy with IPM/CSmonotherapy was as effective as a combination regimen     

Hyperhemolytic transfusion reaction in sickle cell disease

BACKGROUND: An atypical form of life-threatening hemolytic transfusion reaction (HTR) in patients with sickle cell disease (SCD) has been well described in the literature. Continuation of blood transfusion may be lethal, as it can further exacerbate hemolysis. The pathophysiologic mechanism of HTR is not well understood. CASE REPORTS: Two cases of severe HTR in SCD after the transfusion of compatible RBC units are reported. Hemolysis of both autologous and transfused cells was documented in Case 1 by urine Hb high-performance liquid chromotography. Multispecific HLA antibodies were identified in Case 1. Reticulocytopenia was noted in both cases during the acute hemolytic process. This was followed by a rise in reticulocyte count during receipt of IVIG and steroid therapy. Bone marrow examination during reticulocytopenia in Case 2 showed erythroid hyperplasia. CONCLUSION: In SCD, both mature sickle cells and sickle reticulocytes adhere more readily to macrophages. In view of the bone marrow aspiration results, it appears that the recipients' HbS cells are destroyed by hyperactive macrophages and that the reticulocytopenia observed during HTR is likely to be due to peripheral consumption (i.e., destruction by macrophages), rather than suppression of erythropoiesis. Cessation of hemolysis during IVIG and steroid treatment may be due to IVIG's blocking of the adhesion of sickle cells and reticulocytes to macrophages, together with steroid suppression of macrophage activity.