Previous studies have demonstrated variability in the phenotype of rat C6 glioma cells. In the present study, we compared morphology, growth rate, and beta-adrenergic regulation of gene expression in early (P39-47) and late (P55-90) passage C6 cells. Morphological changes were observed in five independently derived, late passage populations. In four of the five, the untreated cells were more polygonal than the fibroblast-like parental cells, and only a small fraction exhibited process outgrowth after dbcAMP treatment. Untreated cells from the fifth late passage population had longer cytoplasmic processes than parental cells and responded to dbcAMP with further process outgrowth. All late passage populations had shorter generation times than the parental cells. In early passage cells, treatment with the beta-adrenergic agonist, isoproterenol (IPR), resulted in an increase in c-fos mRNA and a decrease in c-jun mRNA (Gu-bits RM, Yu H: J Neurosci Res, 30:625-630, 1991). Both of these immediate early gene responses were irreversibly lost between P50 and P55. Additional differences in basal or IPR-induced mRNA levels were observed for beta-APP, GFAP, NGF, and PPE, but not for a number of other mRNAs. These results are discussed in relationship to previously described differences in the ability of early and late passage C6 cells to accumulate cAMP (Mallorga P, et al.: Biochim Biophys Acta 678:221-229, 1981). 相似文献
Objective: Plasma soluble thrombomodulin level reflects endothelial damage. The plasma thrombomodulin level at birth is increased in asphyxiated full-term infants. There is no report of plasma thrombomodulin level in premature infants. To determine the thrombomodulin level in premature infants and whether it might reflect endothelial damage, we examined the plasma thrombomodulin level in very low birthweight (VLBW) infants at birth. Methods: Forty-five VLBW infants, of whom 14 had perinatal asphyxia complications, were recruited. As a control, 50 full-term infants wimout complications were also studied. Plasma thrombomodulin concentration, pH, base deficit, serum creatinine and D-dimer concentration, platelet count and fibrinogen concentration were measured within 1 hour after birth. Results: There were significant differences in plasma pH, creatinine concentration, platelet count, antithrombin in activity and D-dimer concentration between VLBW infants and full-term infants. Plasma thrombomodulin concentration (39. 0 (16. 6–93. 7) vs 27. 0 (16. 6–39. 1) μg/L, p < 0. 0001) and plasma taombomodulin-to-serum creatinine ratio (0. 82 (0. 19–2. 65) vs 0. 47 (0. 24–0. 70) μg/μmol, p < 0. 0001) were significantly higher in VLBW infants than those in full-term infants. By univariate analyses for all neonates, there were significant relations between plasma thrombomodulin concentration and gestational age, birthweight, plasma pH, creatinine concentration, platelet count and antithrombin in activity. A stepwise multiple linear regression model using the above variables as dependent factors showed only birthweight contributed significantly to plasma thrombomodulin concentration (plasma thrombomodulin concentration (μg/1) = 45. 677–0. 006 (birthweight; g), r2= 0. 323, p < 0. 0001, n= 94). Plasma thrombomodulin concentration and plasma thrombomodulin-to -serum creatinine ratio in VLBW infants with asphyxia were higher than in those without asphyxia, but not significantly different (43. 2 ± 17. 7 vs 38. 3 ± 8. 5 μg/1 and 0. 92 ± 0. 60 vs 0. 83 ± 0. 37 μg/μmol). Conclusion: Plasma thrombomodulin level in VLBW infants shows a high value at birth, and we consider the main factor responsible for this elevation may be endothelial damage or low clearance rate of thrombomodulin, which may be related to early gestational age. 相似文献
The survival of low birthweight infants £2000g born in the central Queensland area during the years 1979 to 1991 was examined. Five hundred and sixty such infants were either delivered at one of the two Rockhampton obstetric units (Rockhampton Base Hospital and the Mater Misericordiae Hospital) or retrieved from outlying central Queensland areas. Both hospitals had intensive care nurseries capable of ventilation and infants were transferred to tertiary centres only for cardiac or surgical treatment. The study involved all liveborn infants', including those with lethal malformations and all deaths up to the time of discharge. Survival rates were as follows: £500 g 0%, 501 £750 g 30%, 751 £1000 g 51%, 1001 ± 1500 g 79%, 1501 £2000g 93%. The survival of Aboriginal infants and outborn infants were found to be essentially the same as the overall group. 相似文献
Ca(++)-dependent monoclonal antibody specific to gamma-carboxyglutamic acid (Gla) domain of protein C was produced. It did not cross-react to the other vitamin K-dependent plasma proteins but to protein C of the other species. Using this monoclonal antibody, PC01, rabbit (170 micrograms), rat (60 micrograms) and mouse (40 micrograms) protein Cs were isolated from 100 ml of their plasma by affinity chromatography. All of these protein Cs were two chain form linked by disulfide bond as well as human protein C and activated by thrombin-thrombomodulin complex. Rat and mouse protein Cs showed similar characters to human protein C. On the other hand rabbit protein C had different M(r) of heavy and light chains and showed lower anticoagulant activity compared with human protein C. 相似文献
We have examined the patterns of expression of the major intermediate filament (IF) protein mRNAs during development of the hamster brain. Quantitative northern blotting was used to examine changes in the levels of mRNAs for the low, middle and high molecular weight neurofilament proteins (NF-L, NF-M, NF-H) as well as peripherin, vimentin and glial fibrillary acidic protein (GFAP). Total RNA was isolated from hamster brains at embryonic (E) days 12 and 14 and postnatal (P) days 1, 3, 5, 7, 9, 11, 13, 15, 20, 28 and 60-90 (adult), and probed with specific IF cDNAs. Northern blotting revealed that NF-L and NF-M mRNAs were present at very low levels in embryonic brain and that significant expression of these genes only occurred postnatally when the levels increased dramatically until P28 and then declined again in the adult. Increases in NF-H mRNA levels were somewhat delayed relative to those of NF-L and NF-M. NF-H mRNA was not seen at embryonic stages and was expressed at very low levels prior to P9; after that time the levels increased rapidly until P28 and then declined in the adult. Two of the type III IF genes, peripherin and vimentin, followed a pattern of expression opposite that of the NF genes. Both peripherin and vimentin mRNAs were present in embryonic brain and were expressed at higher levels during early postnatal stages than at later times. The magnitude and rate of reduction in vimentin gene expression in the postnatal interval was much greater than that of peripherin. GFAP mRNA levels were extremely low prior to P9 after which a robust increase occurred, followed by a decline in the adult. We discuss the implication of the dramatic changes in IF isotype expression in brain to the pathways of both neuronal and glial development in vivo. 相似文献
ABSTRACT. Two atypical cases of colitis due to cow's milk protein intolerance (CMPI) are reported, affecting preterm infants. One developed a toxic dilatation of the colon and responded well to a casein hydrolysate based feed. The second presented insidiously and failed to tolerate a casein hydrolysate, but responded well to a chicken-based modular feed. 相似文献
Summary. Parameters were obtained from the reproductive organs of ethanol-fed, gossypol-treated Sprague Dawley rats. The experimental animals were fed either on a normal (15.17%) or low protein (8.00%) diet. Measurements included reproductive organ weights, seminal characteristics, serum concentration of testosterone and histological, stereological and histomorphometric evaluation of the testis. The testis size, length and diameter of the seminiferous tubule had the least values in the protein-malnourished, gossy-pol-treated rats (3.01±0.26 g, 0.56 ± 0.03 m, 281.34±11.30 μn), in comparison to corresponding animals which had received ethanol simultaneously with gossypol (3.40 ± 0.25, 0.71±0.06m, 314.42 ± 11.61 μn). As gossypol and ethanol are both associated with reduced reproductive capacity, this unexpected but interesting finding lends support to the hypothesis that either a normal dietary protein or ethanol consumption may modify the action of gossypol on body tissues, including the testis. This effect, presumably mediated through changes caused to the bioavailability of gossypol, modifies its antifertility activity. The present observation further highlights the need to consider the concurrent administration of other drugs, such as alcohol, and the nutritional status in the evaluation of gossypol for various potential uses. 相似文献
1. 1. Acute effects of alcohol and diazepam on reaction time (RT) and event-related potential (ERP) measures were examined in 108 healthy male volunteers.
2. 2. The subjects engaged in a simple RT task at two levels of stimulus intensity during baseline and treatment sessions.
3. 3. Lower stimulus intensity produced increased RTs, increased ERP peak latencies, and suppression of peak amplitudes.
4. 4. Moderate and high doses of alcohol, and high doses of diazepam produced increased RTs. Alcohol suppressed P100 and N100 amplitudes, while diazepam suppressed P100 amplitudes only. P100 amplitudes were correlated to RTs under baseline and treatment conditions.
5. 5. These results were taken as evidence for impaired stimulus detection during alcohol and diazepam intoxication, with both drugs influencing sensory-perceptual processes and alcohol alone influencing the degree of attentiveness.
Author Keywords: alcohol; diazepam; event-related potentials; simple reaction time 相似文献