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1.
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
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Libor Velíek† Jana Velíková Yael Ptachewich Shlomo Shinnar‡ Solomon L. Mosh醇 《Epilepsia》1995,36(2):179-185
Summary We determined the effects of the N-methyl-Daspartate (NMDA) receptor blocker MK-801 (0.05, 0.1, and 0.5 mg/kg intraperitoneally, i.p.) and phenytoin (PHT, 5, 10, and 20 mg/kg i.p.) on flurothyl-induced clonic and tonic-clonic seizures in 9-, 1 5, 30-, and 60-day-old male rats. Both agents had seizure-, age-, and dose-specific effects. The highest dose of MK-801 was anticonvulsant against clonic flurothyl-induced seizures only in 9- and 60-day-old rats, but suppressed tonic-clonic seizures in all ages. The lowest dose of MK-801 (0.05 mg/kg) produced significant anticonvulsant effects only in 15 day old rats. PHT did not have any effect on clonic seizures throughout development. Both doses of PHT (10 and 20 mg/kg) were anticonvulsant against tonic-clonic seizures in adult rats but not in any other age group. The results indicate that NMDA receptors play an important role in tonic-clonic flurothyl-induced seizures throughout development (especially in 15-day-old rats) and that the anticonvulsant effects of PHT may vary at different stages of brain development. 相似文献
4.
Age-Specific Effects of Baclofen on Pentylenetetrazol-Induced Seizures in Developing Rats 总被引:1,自引:0,他引:1
Summary: Purpose : To determine whether seizures have age-specific features, we studied the role of γ-aminobutyric acid, (GABAB) transmission in rats of various ages (9, 15, 30, and 60 postnatal days). Methods: We used a GABA, receptor agonist baclofen (2 or 5 mg/kg intraperitoneally, i.p.) and a GABAB receptor antagonist CGP 35348 (100 or 600 mg/kg i.p.) in the pentylenetetrazol (PTZ)-induced model of clonic and tonic-clonic seizures (100 mg/kg subcutaneously, s.c.).
Results : Whereas baclofen was anticonvulsant and CGP 35348 proconvulsant in most animals, there were distinct age-related differences in the effectiveness of these drugs and the antagonist had some anticonvulsant activity in adults. Furthermore, the two drugs acting at GABAB receptors had a different profile of action in clonic seizures as compared with tonic-clonic seizures.
Conclusions : The differences in the age-specific action of the GABAB agonist and antagonist suggest that different GABAB receptor subsets may mediate the drug effects. The results indicate that putative antiepileptic drugs (AEDs) must be tested during development because it may not be possible to extrapolate age-specific anticonvulsant effects from studies in adult animals. 相似文献
Results : Whereas baclofen was anticonvulsant and CGP 35348 proconvulsant in most animals, there were distinct age-related differences in the effectiveness of these drugs and the antagonist had some anticonvulsant activity in adults. Furthermore, the two drugs acting at GABA
Conclusions : The differences in the age-specific action of the GABA
5.
Total elbow arthroplasty as a treatment option for open elbow fracture is relatively rare described. We reported a 39 years old polytrauma patient with complex open elbow fracture (Gustilo-Anderson type IIIB). The patient presented with large soft tissues defect on dorsal part of the left elbow, ulnar palsy due to the irreparable loss of the ulnar nerve, distal triceps loss due to the complete loss of the olecranon, loss of both humeral condyles with collateral ligaments and complex elbow instability. Only few similar cases have been published. Reconstructive surgery included repetitive radical debridement, irrigation, vacuum assisted closure system therapy, external fixation, coverage of the soft tissue defect with fascia ecutaneous flap from the forearm. Four months after the injury, total elbow arthroplasty with autologous bone graft (from the proximal radius) inserted in the ulnar component, was performed. At 3 years postoperatively, the patient is able to perform an active flexion from 0 to 110 with full pronosupination. Only passive extension is allowed. The ulnar neuropathy is persistent. Patient has no signs of infection or loosening of the prosthesis. 相似文献
6.
Karla ech Barabaszov Ale Slíva Gabriela Kratoov Sylva Holeov Anastasia Volodarskaja Tugrul Cetinkaya Silvie Broov Libor Kozubek Grayna Simha Martynkov 《Materials》2022,15(15)
Today, Ni-Cr steel is used for advanced applications in the high-temperature and electrical industries, medical equipment, food industry, agriculture and is applied in food and beverage packaging and kitchenware, automotive or mesh. A study of input steel powder from various stages of the recycling process intended for 3D printing was conducted. In addition to the precise evaluation of the morphology, particle size and composition of the powders used for laser 3D printing, special testing and evaluation of the heat-treated powders were carried out. Heat treatment up to 950 °C in an air atmosphere revealed the properties of powders that can appear during laser sintering. The powders in the oxidizing atmosphere change the phase composition and the original FeNiCr stainless steel changes to a two-phase system of Fe3Ni and Cr2O3, as evaluated by X-ray diffraction analysis. Observation of the morphology showed the separation of the oxidic phase in the sense of a brittle shell. The inner part of the powder particle is a porous compact core. The particle size is generally reduced due to the peeling of the oxide shell. This effect can be critical to 3D printing processing, causing defects on the printed parts, as well as reducing the usability of the precursor powder and can also change the properties of the printed part. 相似文献
7.
OBJECTIVES: To evaluate patients with Bosworth-type fibular entrapment injuries of the ankle. DESIGN: Retrospective clinical study and analysis of the literature. SETTING: University hospital. PATIENTS: Six cases treated for Bosworth-type fibular entrapment injuries (the Bosworth lesion) in the period 2001 to 2004. INTERVENTION: Five patients were treated with open reduction and internal fixation (ORIF), and 1 patient was treated with closed reduction and cast. RESULTS: All patients treated by ORIF healed without complications with a good subjective outcome. In 1 case treated nonoperatively, an ankle fusion had to be performed 2 years after injury for severe osteoarthritis. Additionally, we have recorded 3 cases, 2 not previously described in the literature, in which the fracture of the fibula was located at the middle or proximal third of its shaft.In the literature we found another 54 cases with dislocation of the fibula behind the posterior tubercle of the distal tibia. The analysis showed that morphology of the Bosworth lesion, as we prefer to refer to this complex fracture-dislocation, changes with age and may be divided into 3 basic types. In children and adolescents the dislocation of the distal fibula is associated with epiphyseolysis of the distal tibia; in young adults the fibula dislocates without fracture; in middle-aged and older adults, the dislocated fibula fractures, probably because of the decreased elasticity. CONCLUSIONS: The Bosworth lesion is a severe injury of the ankle, and its successful treatment requires a correct diagnosis based on careful initial clinical and radiographic evaluation and early surgical treatment. 相似文献
8.
Vermeulen K Strnad M Havlícek L Van Onckelen H Lenjou M Nijs G Van Bockstaele DR Berneman ZN 《Experimental hematology》2002,30(10):1107-1114
OBJECTIVE: Regulation of the cell cycle by cyclin-dependent kinase (CDK) activity occurs at multiple levels and is often altered in human cancers. Therefore, CDK activity has been targeted for drug discovery, and a number of small molecules have now been identified as CDK inhibitors. Plant cytokinin analogues with CDK inhibitory activity and antiproliferative effects were studied to characterize the cellular basis of the cytotoxic effect. METHODS: The IC(50) value (concentration at which 50% of the cell proliferation is inhibited) and AC(50) value (concentration at which 50% of the cell population is apoptotic) were determined by flow cytometry and microscopy, respectively. A new multiparametric flow cytometric analysis was used to study the sequence of different apoptotic events. In this assay, analysis of phosphatidylserine exposure, mitochondrial membrane depolarization, activation of caspases and DNA condensation were combined. RESULTS: Treatment of Jurkat and KG1 cells with the CDK inhibitors results in a decrease of viable cells and a parallel increase in percentage of apoptotic cells. Apoptosis was accompanied by a rapid decrease of mitochondrial membrane potential, which precedes DNA condensation, exposure of phosphatidylserine and activation of caspases. CONCLUSIONS: The main cellular mechanism of the antiproliferative effect of plant cytokinin analogues with CDK inhibitory activity is the induction of apoptosis. The multiparametric flow cytometric technique allowed to follow the kinetics of various aspects of apoptotic cell changes and demonstrated that cytokinin analogue-induced apoptosis starts through the mitochondrial pathway. This technique could also become of value for the rapid screening of pro-apoptotic properties of chemotherapeutic compounds. 相似文献
9.
The diphtheria epidemic in the former Soviet Union reached Azerbaijan in 1991, when 66 cases of diphtheria were reported, a number that compared with 4 cases in 1990. From 1990-1996, 2182 cases of diphtheria and 286 diphtheria fatalities (case fatality rate: 13.1%) were reported in Azerbaijan, primarily among persons 5-39 years of age. Almost 45% of cases and 61% of deaths occurred among children 5-14 years of age. The high burden of severe disease among children and young adults suggested a different pattern of preexisting immunity against diphtheria in the Azerbaijani population than was observed in the concurrent diphtheria epidemic in Russia. Because resources were limited in Azerbaijan, mass immunization of the population was carried out in stages, focusing initially on school-aged children. Mass immunization campaigns targeting children were moderately successful in stabilizing the epidemic; mass immunization campaigns targeting both adults and children were eventually needed to fully stop the epidemic. 相似文献
10.
Urban O Vitek P Fojtik P Kliment M Janik D Chalupa J Albin A 《Hepato-gastroenterology》2008,55(82-83):351-355
BACKGROUND/AIMS: Laterally spreading tumors (LST) are flat elevated neoplastic lesions with diameters equal to or greater than 10 mm. The treatment results of 138 lesions in 131 patients are presented here as a part of a retrospective analysis. METHODOLOGY: Two gastroenterology centers participated in the study in the period from 1/2002-12/2006. During colonoscopy, each superficial lesion was classified according to the Paris endoscopic classification. Endoscopic mucosal resection (EMR) lift and cut was employed. Treatment was considered successful when both endoscopic and histo-pathological criteria of complete resection were fulfilled. RESULTS: A total of 138 LST in 131 patients were diagnosed. Average LST diameter was 25 mm. A total of 5 (3.6%) lesions in 4 patients were referred for primary surgery. One patient was treated with argon plasma coagulation only. EMR was attempted for 132/138 (95.7%) of all LST and was successful in 125 (90.6%) cases. Complications occured in 16/132 (12.1%) patients. Severe complications, defined as decession, emergency surgery, emergency endoscopy and transfusion of eryhrocyte concentrate occured in 5/132 (3.8%). One (0.7%) 69 year-old-male patient died on the third day following EMR due to complications of acute myocardial infarction. CONCLUSION: LST lesions could be efficiently treated with EMR lift and cut method with a reasonable rate of complications. 相似文献