Morphologic,cytochemical and neurochemical characterization of the human medulloblastoma cell line TE671

Summary Medulloblastoma cell line TE671 was characterized by morphologic, cytochemical, neurochemical, and growth criteria. In contrast to the uniform, in vivo histopathologic appearance of the tumor, TE671 in vitro exhibits six morphologic subtypes (Types I–VI) in varying percentages over 14 days in culture. TE671 grows as a monolayer by the merging of separate foci. Cells were positive for Periodic acid Schiff (PAS) and reticulum, and negative for the glial marker, glial fibrillary acid protein (GFAP). Receptors for human Cab (EAC) were present on 19% of the cells. Neural associated isoenzymes, neuron specific enolase (NSE) and creatine kinase (CK-BB) were demonstrated in TE671. Progeny of a single clonogenic cell manifested the morphologic heterogeneity of cell types (I–VI). The absence of markers specific for glial cells suggests that TE671 is an early (less differentiated) precursor. TE671, the only continuous human medulloblastoma cell line, provides an experimental model with which to compare and identify the subpopulation of neoplastic cells in medulloblastoma ex vivo.     

Cytochemistry and biochemistry of acid phosphatases. VI: Immunoelectron microscopic studies on human prostatic and leukocytic acid phosphatases

Using different antisera against secretory and lysosomal prostatic acid phosphatases, the localization of the respective antigens was studied in the human prostate at the ultrastructural level. Secretory acid phosphatase was confined exclusively to the secretory vacuoles of the glandular cells. Discharge of the secretory material occurs in a merocrine type of secretion. The identical antigen could be localized in the primary and secondary granules of neutrophil and eosinophil granulocytes separated from human peripheral blood. The antiserum used was also cross-reactive with the canine prostate, where a very distinct immunoreaction was observed with the secretory granules of the glandular cells. The antibodies directed against lysosomal acid phosphatases prepared from prostatic homogenates consistently gave a positive immunoreaction with dense bodies, lipofuscin, and secretory granules. The respective antigens were present also in neutrophil and eosinophil granulocytes. These findings do not identify the existence of a prostate-specific acid phosphatase, which does not exist. The secretory form of the isoenzymes, however, is clearly distinct from the lysosomal form, both of which are present in granulocytes. Therefore the origin of acid phosphatases elevated in peripheral blood in cases of metastatic prostatic cancer could be either the carcinomatous cells or leukocytes destroyed during the process of metastasis.     

Effects of autotransfusion of mediastinal shed blood on biochemical markers of myocardial damage in coronary surgery

BACKGROUND: Previous studies have shown conflicting results regarding the effect of autotransfusion of mediastinal shed blood after coronary artery bypass grafting (CABG) on the serum levels of myocardial band (MB) isoenzymes of creatine kinase (CK-MB) and cardiac troponins. The effect of autotransfusion on serum levels of human heart fatty acid binding protein (H-FABP), another marker of myocardial necrosis, has not been studied. The aim of the present study was to investigate the effects of autotransfusion of mediastinal shed blood on the serum levels of CK-MB, cardiac troponin T (cTnT), and H-FABP after uncomplicated primary CABG. METHODS: Fifty patients were randomized to post-operative autotransfusion of mediastinal shed blood or no autotransfusion. Blood samples for the analysis of the biochemical markers of myocardial damage were drawn pre-operatively and 1, 4, 12, 24, 48, and 72 h after the termination of cardiopulmonary bypass. Samples from the mediastinal shed blood were collected after 1 and 4 h. RESULTS: The levels of the biochemical markers of myocardial injury were all markedly elevated in mediastinal shed blood. Autotransfusion did not significantly affect the serum levels of cTnT or H-FABP. However, during the early post-operative hours, there was a trend towards a higher level of cTnT and H-FABP in the autotransfusion group. During the first 24 h after surgery, the autotransfusion group had a significantly higher serum level of CK-MB. CONCLUSION: Post-operative autotransfusion of mediastinal shed blood may contribute to elevated serum levels of biochemical markers of myocardial injury.     

高氧液预处理对心脏瓣膜置换术患者心肌肌钙蛋白Ⅰ和心肌酶学的影响

目的观察高氧液预处理对心脏瓣膜置换手术患者缺血-再灌注心肌的保护作用。方法将30例择期心脏瓣膜置换术患者随机分成观察组和对照组。对照组患者在麻醉后切皮前（T0）至心肺转流（CPB）开始后10min,静滴复方氯化钠注射液10ml／kg;观察组给予相等容量的高氧液。分别于T0、CPB开始后1h（T1）、主动脉开放后2h（T2）、24h（T3）测定乳酸脱氢酶（LDH）、肌酸激酶（CK）、肌酸激酶同功酶（CK—MB）、α-羟丁酸脱氢酶（HBDH）和心肌肌钙蛋白I（cTnI）。结果与T0时比较,两组T1、T2、T3时心肌酶和cTnI测定值均增高（P〈0．05）。两组间比较,LDH、CK—MB在T2、T3时,CK和cTnI在T1、T2、T3时,HBDH在T1时,观察组明显低于对照组（P〈0．05）。术后24h多巴胺用量,观察组明显低于对照组（P〈0．01）。结论高氧液预处理能减轻心肌缺血-再灌注损伤后酶学改变。     

琼脂糖等电聚焦法快速测定碱性磷酸酶同工酶

本研究的目的是建立高灵敏度分离碱性磷酸酶同工酶的方法，具体采用琼脂糖等电聚焦法分离其同工酶，电泳前先用神经氨酸苷酶对几种组织提取液和病人血清进行处理。该法可将肝、骨、小肠以及胎盘同工酶分离出多条区带，具有操作简单、灵敏度和分辨率高、重复性好的优点     

Myocardial catecholamine responsiveness of spontaneously hypertensive rats as influenced by swimming training

Summary Alterations of myocardial mechanical catecholamine responsiveness by swimming training (2×90 min/day, 4 weeks) were examined in 13-week-old spontaneously hypertensive male rats (SHR). The relationships between myocardial mechanical catecholamine responsiveness and ventricular -adrenoceptors as well as myosin isoenzyme pattern were also examined. Compared with sedentary controls, trained rats showed a greater responsiveness to isoproterenol (10^–6 mol/l) on isometric tension (T) and its first derivative (dT/dt) (T:0.45±0.55 vs. –0.15±0.11 10^–2 N/mm², p<0.01, dT/dt: 17.1±10.1 vs. 8.3±3.6 10^–2 N/mm²·s, p<0.05). In sedentary SHR, dT/dt_max increased significantly, whereas developed tension decreased slightly, coupled with a decrease of time to peak tension by high dose (10^–6 mol/l) isoproterenol. Therefore, it can be stated that dT/dt is a better indicator for catecholamine sensitivity than isometric tension. -adrenoceptor density ([³H]-dihydroalprenolol binding) decreased significantly in trained rats (68.7±7.62 vs. 102.4±4.37 fmol/mg protein, p<0.01) with no significant difference in K_D values (4.61±2.26 vs. 6.11±1.94 nM, ns). In addition, myosin isoenzyme pattern revealed by pyrophosphate gel electrophoresis shifted towards VM-1 after swimming training. The increased catecholamine sensitivity of fast contracting myocardium is, in principle, compatible with the assumption of cAMP-dependent regulation of myofibrillar ATPase activity (21) or cross bridge kinetics (9), although other postreceptor processes should also be taken into consideration for the increased catecholamine sensitivity.Supported by the Deutsche Forschungsgemeinschaft     

猴头部冲击性脑损伤的判别

为在航空弹射救生的头部冲击伤的研究中区别脑功能性与器质性损伤的界限，使用高速动态加载机，对２４只猴头进行了不同冲击载荷的撞击实验，依据有关临床诊断标准判别，冲击后８只猴发生了单纯性脑震荡，６只猴发生了脑实质性损伤，而其中的３只猴又伴有脑震荡症状。结果表明，发生了脑震荡的猴都出现了暂短生理反射减弱或消失，呼吸和心率减慢，脑干神经细胞尼氏体有减少现象脑震荡伴有脑损伤的猴脑脊液中还检出ＣＫ－ＢＢ酶和红细     

Identification of two arginase isoenzyme activities along the nephron of Meriones shawi

 Conflicting theories on the existence of several renal arginase isoenzymes remain in debate. Because the activity of arginase is high in two embryologically different nephron segments of the Meriones shawi kidney, namely the cortical (CPST) and medullary (OSPST) proximal straight tubule and the outer medullary collecting duct (OMCD), we postulate that these nephron segments may contain different isoforms. Isolated nephron segments were dissected from collagenase-treated kidneys. Tubules were permeabilized with Triton X-100 (0.25%) and incubated with increasing Arg concentrations to characterize the arginase activity. The results were as follows: (1) in OMCD, one arginase isoform (E₁), characterized by a high Arg affinity (1.160 mM), was present; (2) in CPST, two arginase isoforms were discovered – one, E₁, had a similar K _m (1.407 mM) to that found in OMCD whereas the other (E₂) had a low affinity for Arg (K _m =18.8 mM); and (3) in OSPST, two isoenzymes were present – E₁ which had a K _m of 1.478 mM and the second isoform that we named E₂ which had a K _m of 9.07 mM. In addition, arginase located in CPST and OMCD was strongly inhibited by Orn and Lys. The K _i value for Lys varied between 1.635 and 2.288 mM. Therefore, this work demonstrates that two arginase isoforms are present in the kidney of Meriones shawi. Isoform E₁ is present in the proximal tubule and the collecting duct whereas isoform E₂ is restricted to the proximal tubule. Received: 13 August 1998 / Accepted: 25 September 1998     

Asscessment of the clinical value of CK-M2 and oligosaccharide protein inserum from patients with gastric carcinoma

AIM To evaluate the clinical value of creatine kinase macroisoenzyme type 2 (CK-M2) and oligosaccharideprotein (OP) in serum from patients with gastric carcinoma (GC).METHODS Serum level of CK-M2 was detected by agar gel electrophoresis. OP concentration was measuredby an enzyme immunoassay.RESULTS Serum levels of CK-M2 and OP in 57 cases of GC were significantly higher than those in 51 caseswith gastric precancerous lesion and 28 controls. The diagnostic sensitivity and specificity for GC with CK-M2 was 56.10% and 98.63% respectively. CK-M2 and OP were not associated with histologic type and degreeof differentiation.CONCLUSION These results suggest that CK-M2 may serve as a marker to diagnose GC, and the specificityis higher, whereas OP is not more significant for GC diagnosis, but it could be a useful indicator forevaluation the status of body immune.     

Selective phosphodiesterase inhibitors for the treatment of bronchial asthma and chronic obstructive pulmonary disease

Theophylline is commonly used in the treatment of obstructive airway diseases. The identification and functional characterization of different phosphodiesterase (PDE) isoenzymes has led to the development of various isoenzyme-selective inhibitors as potential anti-asthma drugs. Considering the distribution of isoenzymes in target tissues, with high activity of PDE3 and PDE4 in airway smooth muscle and inflammatory cells, selective inhibitors of these isoenzymes may add to the therapy of chronic airflow obstruction. However, initial data from clinical trials with selective PDE3 and PDE4 inhibitors have been somewhat disappointing and have tempered the expectations considerably since these drugs had limited efficacy and their use was clinically limited through side effects. The improved understanding of the molecular biology of PDEs enabled the synthesis of novel drugs with an improved risk/benefit ratio. These 'second generation' selective drugs have produced more promising clinical results not only for the treatment of bronchial asthma but also for the treatment of chronic obstructive pulmonary disease.