Extracellular levels of adenosine and its metabolites in the striatum of awake rats: inhibition of uptake and metabolism

The level of purines in the striatum of awake, freely moving rats was studied using microdialysis. The calculated extracellular concentration of adenosine and its metabolites inosine and hypoxanthine was very high immediately after implantation of the dialysis probe but decreased within 24 h to a level which remained stable for two days. Using in vitro calibration to determine the relative recovery of the dialysis probes we estimated resting levels in the striatal extracellular space to be 40, 110 and 580 nM, respectively. Inhibition of adenosine deaminase by deoxycoformycin produced a significant 1.4-fold increase in extracellular adenosine levels and a fall in inosine and hypoxanthine. A combination of three uptake blockers (dipyridamole, lidoflazine and nitrobenzylthioinosine), caused a 4.5-fold increase in extracellular adenosine levels without any change in inosine or hypoxanthine levels. After uptake inhibition deoxycoformycin did not have any significant effect. The present results show that the microdialysis technique can be used to determine levels of purines in the extracellular fluid of defined brain regions in awake animals. The high levels recorded during the first several hours after implantation may be artefactually high and reflect trauma. The results also show that adenosine levels can be altered in vivo by inhibitors of adenosine transport and adenosine deaminase. The present results indicate that the physiological adenosine level in striatal extracellular space is in the range 40-460 nM.     

General morphology and capsid fine structure of African swine fever virus particles

The structure of African swine fever virus particles has been examined by electron microscopy. The analysis of virions prepared by negative staining, thin sectioning, and freeze-drying and shadowing showed that the virus particle was composed of several concentric structures with an overall icosahedral shape. The inner region of the virus particles was a nucleoid that was surrounded by a membrane covered by the capsid. The capsid had side-to-side dimensions of 172 to 191 nm and was built up by capsomers arranged in an hexagonal lattice. Computer-filtered electron micrographs of either negatively stained or freeze-dried and shadowed capsids revealed capsomers with a hexagonal outline and a hole in the center. The intercapsomer distance ranged from 7.4 to 8.1 nm. The triangulation number of the capsid was estimated to be 189 to 217, indicative of 1892 to 2172 capsomers. Extracellular African swine fever virus particles had an external membrane that resembled the cytoplasmic unit membrane.     

The Prader-Willi syndrome with a 15/3 translocation.

A de novo translocation of 15q to 3p with complete monosomy of 15p and partial monosomy of 15q was detected by trypsin banding on peripheral lymphocytes of a 5-year-old boy with Prader-Willi syndrome (severe mental retardation, dyslalia, cryptorchidism, and muscular hypotonia). The pathogenic role of chromosome 15 abnormalities in the aetiology of this syndrome is discussed.     

Work-induced potassium changes in skeletal muscle and effluent venous blood assessed by liquid ion-exchanger microelectrodes

Using liquid ion-exchanger semimicroelectrodes with a side pore, we measured changes of extracellular potassium concentration (K_e ⁺) in adult rabbit and cat gastrocnemius muscles and in venous effluent blood flowing from the cat gastrocnemius muscle during various bouts of activity induced by sciatic nerve stimulation.

动态监测SARS病人IL-1α、IL-1β、TNFα和IL-6含量及其意义

目的 :动态监测SARS病人IL 1α、IL 1β、TNFα和IL 6含量并探讨其意义。方法 :采用酶联免疫吸附法定量检测早期、恢复期SARS病人以及出院后SARS随访者 ,一线未患SARS健康医护人员及健康体检者血清中IL 1α、IL 1β、TNFα和IL 6含量。结果 :IL 1α和IL 1β含量在早期、恢复期与其他组比较均显著升高 (P <0 0 5 )。SARS早期组TNFα均值显著高于其他组(P <0 0 0 5 ) ,SARS恢复期组均值显著高于SARS随访组、急诊等一线未患SARS组和健康对照组 (P <0 0 1)。SARS早期组IL 6均值显著高于其他各组 (P <0 0 0 5 ) ,SARS随访组与急诊等一线未患SARS组和健康对照组间均值比较 ,均有显著差异 (P <0 0 1)。结论 :SARS在发病过程中其病理损伤与细胞因子IL 1、TNFα和IL 6有关。     

Single nephron glomerular filtration rate ratios of superficial,intercortical and juxtamedullary nephrons in rats during development

Summary In 20, 40 and 60-day-old rats the filtration rate was studied, using Baines modification of Hanssen's Na₄Fe(¹⁴CN)₆ method enabeling the determination of single nephron glomerular filtration rate (SNGFR) ratio between superficial (S), intercortical (I) and juxtamedullary (J) nephrons. The proximal tubule lengths were determined as well. A close correlation was obtained between age and S/I, I/J and S/J of proximal tubule lengths and between age and I/J, S/J¹⁴C-activities of ferrocyanide. Presented findings confirm the data on the increasing role of superficial nephrons in the course of postnatal development of rat.     

Reactivity of different LH and FSH standards and preparations in the world health organization matched reagents for enzyme-linked immunoassays of gonadotrophins

The immunoreactivity of various LH and FSH calibration standards and recombinant preparations in the enzyme-linked immunoassay (EIA) systems for gonadotrophins developed for the Special Programme of Research in Human Reproduction of the World Health Organization (WHO) were compared. The preparations tested included three LH and two FSH pituitary standards (calibrated against LH 80/552 and 68/40 and FSH 78/549 respectively) provided with the EIA or radioimmunoassay WHO matched reagent kits, the pituitary preparation LER-907, and recombinant human LH (rhLH) and FSH (rhFSH). Simultaneous curve fitting of the EIA dose-response curves revealed no significant differences among the slopes generated by the WHO LH standards and LER-907; in contrast, no parallelism was found between the curves of rhLH and the pituitary-derived LH standards. No significant differences were found among the slopes of the curves elicited by the pituitary and recombinant FSH preparations. Each LH preparation exhibited a high degree of charge heterogeneity. Considerable variations in charge isoform distribution among the WHO LH standards, rhLH and LER-907 were also evident. In contrast, the FSH preparations were less heterogeneous and exhibited minor differences in charge distribution. Despite the existing differences in charge isoform distribution, all the pituitary-derived preparations as well as rhFSH seem appropriate for using as calibration standards in this particular EIA system.     

Autoimmune response in women with endometriosis

PROBLEM: The aim of this study was to investigate the humoral immune response to the female reproductive tissues associated with endometriosis (grades I-III) (n = 52), compared with a group of healthy fertile women (n = 6). METHOD OF STUDY: An ELISA with cultured endometrial cell lines in monolayer was used to determine the presence of anti-endometrial antibodies (AEA). For anti-zona pellucida antibodies (AZPA) assessment a conventional ELISA was employed. The presence of antibodies to human sperm (ASA) was performed by the tray agglutination test (TAT). RESULTS: Endometriosis grade III was associated with AEA in serum in the 45.4% of patients. The presence of AEA in serum is correlated to endometriosis severity. The 8.7% of women with endometriosis showed ASA, and the 10.9% of them were positive for AZPA. Antibodies specific for endometrial cells do not show reaction to any gamete antigen (sperm or oocyte), suggesting that they are not cross reactive. CONCLUSIONS: Severity of endometriosis is correlated with high titers of AEA.