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21.
J. Rodrigo O. Uttenthal M.L. Bentura N. Maeda K. Mikoshiba R. Martinez-Murillo J.M. Polak 《Brain research》1994,634(2)
The subcellular localization of the inositol 1,4,5-trisphosphate receptor protein, P400, was studied in the vestibular complex, an area to which Purkinje cells project, as well as in neurons of the dorsal cochlear nucleus and in ectopic Purkinje cells of adult rat brain. The receptor was demonstrated by electron microscopical immunocytochemistry using the avidin-biotin peroxidase complex procedure, with the monoclonal antibody 4C11 raised against mouse cerebellar inositol 1,4,5-trisphosphate receptor protein. Immunoreactivity was found in preterminal fibres and terminal boutons in the nuclei of the vestibular complex, generally associated with the subsurface systems and stacks or fragments of smooth endoplasmic reticulum. Ectopic Purkinje cells and cartwheel cells of the dorsal cochlear nucleus also displayed immunoreactivity, but this was much less intense in the latter. The results of the present study suggest that this receptor protein, involved in the release of Ca2+, is located in sites that enable it to influence the synthesis, transport and release of neurotransmitters. 相似文献
22.
Marek Andrzej Deja Krzysztof S Go?ba Marcin Malinowski Stanis?aw Wo? Maciej Kolowca Jolanta Biernat Maciej Kajor Tomasz J Spyt 《European journal of cardio-thoracic surgery》2005,28(4):551-557
OBJECTIVE: The studies showing the superior characteristics of ITA graft and its impact on the clinical results of coronary artery surgery were performed with ITA harvested almost exclusively as a pedicle. This study assesses the impact of ITA skeletonization on its innervation and reactivity. METHODS: Segments of skeletonized and non-skeletonized ITA were stained with antibodies against protein S-100 to look for the presence of sympathetic nerve fibers. The functional studies were performed on segments of discarded human pedicled ITA that were divided into two 3mm rings, one skeletonized and another non-skeletonized. We compared concentration-effect relationships for the contraction to norepinephrine and endothelium-dependent relaxation to acetylcholine and bradykinin, as well as endothelium-independent relaxation to sodium nitroprusside in skeletonized and non-skeletonized segments of the same ITA. RESULTS: Skeletonized ITA was devoid of protein S-100 positive nerve fibers. It contracted stronger (maximal response 37.0+/-2.04 vs. 25.4+/-1.83mN (P<0.001)) and was twice as sensitive to norepinephrine: pD(2) 6.03+/-0.10 vs. 5.70+/-0.12 (P=0.035). The endothelium-dependent relaxation responses did not differ between skeletonized and non-skeletonized ITA rings. The skeletonized ITA rings appeared over 10 times more sensitive to sodium nitroprusside: pD(2) 6.66+/-0.20 vs. 5.59+/-0.37 (P=0.012)-potency ratio 11.61. The maximal responses did not differ significantly: 112.0+/-6.71 vs. 129.4+/-16.4% (P=0.33). CONCLUSIONS: Skeletonization results in sympathectomy of ITA. It has no effect on endothelium-dependent relaxation but increases reactivity of ITA to norepinephrine. This augmented response to alpha-agonist is small, in comparison with over a ten-fold increase in sensitivity to sodium nitroprusside. Pedicled and skeletonized ITA are functionally significantly different vessels when studied in vitro. 相似文献
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Marcin Sibiński Marek Synder B?azej Pruszczyński 《Chirurgia narzadów ruchu i ortopedia polska》2006,71(1):33-36
The purpose of the study was to assess hip joint development after the treatment of DDH with overhead traction and closed reduction complicated by growth disturbances of the proximal femoral epiphysis. Comparison was also made between joints affected by AVN and other treated joints. Antero-posterior radiographs of 107 hip joints (81 children) done during treatment and follow-up were retrospectively reviewed. The average age was 14.2 months (from 5 to 33 months) and age at the final follow up 20.7 years (minimum 14 years). AVN was detected in 31 (29%) of the hip joints. Type II necrosis according to Bucholz and Ogden classification system was the most common one. In the hips affected by growth disturbances of proximal femoral epiphysis there were worse final clinical and radiological results, osteoarthrosis and elongation of acetabulum were more often seen in comparison to other treated joints. There was no difference in terms of other parameters describing acetabulum. In 19 out of 31 cases deformity of femoral head was noted. AVN may present as a wide spectrum of pathology from mild, probably not significant growth disturbances of physis to severe deformity and lateralisation of femoral head. Statistically hips with AVN had worse final results and in cases with good congruity prognosis is often uncertain due to aspherical femoral head and secondary osteoarthrosis. Acetabular development is most often unaffected by AVN. 相似文献
26.
Mazur G Bogunia-Kubik K Wróbel T Karabon L Polak M Kuliczkowski K Lange A 《Immunology letters》2005,96(2):241-246
Multiple myeloma (MM) is a plasma cell malignancy characterised by bone marrow infiltration and the presence of a monoclonal protein in serum and/or urine. Interleukin-6 (IL-6) has been identified as one of the most important cytokines that contributes to myeloma cell survival and proliferation. Recent investigations suggest involvement of another cytokine, IL-10, in the activation of MM cells. The present study aimed to determine whether there is an association between the polymorphic features located within the promoter regions of IL-6 and IL-10 genes and progression the disease. IL-6 (-174 G/C) and IL-10 (-1082 A/G, -819 C/T, -592 A/C) promoter single nucleotide polymorphisms (SNPs) were determined by PCR-SSP technique using commercial primers. Our single centre results were compared with the data from literature and combined in cumulative analysis employing the Mantel-Haenszel method. In univariate analysis, only IL-10 ACC genotype tended to prevail in our (Polish) group of patients. None of IL-6 genotypes or IL-10 (-1082) alleles was found to associate with MM disease either in our single centre or in cumulative study. Among patients who died within 36 months of diagnosis, a significant prevalence (P < 0.05) of IL-6 heterozygous cases as opposed to IL-6 homozygotes was observed. IL-6 and IL-10 promoter gene polymorphisms were not found to associate with the susceptibility to the development of MM. However, the IL-6 polymorphic features appeared as factors that might affect the survival of MM patients. The latter observation warrants further study. 相似文献
27.
Plasma alpha beta levels have been examined in sporadic Alzheimer's disease yielding conflicting results; both no difference and an increase in plasma concentrations of alpha beta42 and alpha beta40 in sporadic cases of AD as compared to controls have been reported. Elevated plasma alpha beta42 levels may be detected several years before the onset of symptoms (in mild cognitive impairment stadium). Levels of alpha beta40 and alpha beta42 were measured in plasma from 54 patients with AD, 39 subjects with MCI and 35 controls using a commercially available ELISA. Mean plasma alpha beta42 levels were significantly higher in MCI as compared to both AD (P < 0.001) and control subjects (P < 0.001), while alpha beta40 did not differ between the groups. No correlations were observed between alpha beta levels and age, MMSE scores or gender. According to ROC curve analysis the maximum accuracy in discriminating MCI versus both controls and AD subjects has been achieved using a cut-off value of 3.8. 相似文献
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Functional uncoupling of MCM helicase and DNA polymerase activities activates the ATR-dependent checkpoint 总被引:19,自引:0,他引:19
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The ATR-dependent DNA damage response pathway can respond to a diverse group of lesions as well as inhibitors of DNA replication. Using the Xenopus egg extract system, we show that lesions induced by UV irradiation and cis-platinum cause the functional uncoupling of MCM helicase and DNA polymerase activities, an event previously shown for aphidicolin. Inhibition of uncoupling during elongation with inhibitors of MCM7 or Cdc45, a putative helicase cofactor, results in abrogation of Chk1 phosphorylation, indicating that uncoupling is necessary for activation of the checkpoint. However, uncoupling is not sufficient for checkpoint activation, and DNA synthesis by Polalpha is also required. Finally, using plasmids of varying size, we demonstrate that all of the unwound DNA generated at a stalled replication fork can contribute to the level of Chk1 phosphorylation, suggesting that uncoupling amplifies checkpoint signaling at each individual replication fork. Taken together, these observations indicate that functional uncoupling of MCM helicase and DNA polymerase activities occurs in response to multiple forms of DNA damage and that there is a general mechanism for generation of the checkpoint-activating signal following DNA damage. 相似文献
30.
Trejter M Markowska A Belloni AS Nussdorfer GG Malendowicz LK 《International journal of molecular medicine》2002,9(1):81-84
Pseudoachondroplasia (PSACH) is an autosomal dominant disorder characterized by disproportionate short stature and precocious osteoarthritis. Radiographic manifestations include epiphyseal, metaphyseal and vertebral abnormalities. Mutations in the cartilage oligomeric matrix protein (COMP) have been identified to cause PSACH. Most of them affect one of the eight calcium-binding domains of COMP. We describe a clinically and radiologically typical PSACH 4-year-old girl and her 31-year-old father. A novel mutation, 1345-1347CCC deletion in exon 13, of COMP was identified in both patients. The deletion would be expected to result in the loss of the conserved proline at codon 449 from the sixth calcium-binding domain. This result further supports that COMP is the only gene, discovered to date, responsible for PSACH across different populations and that the calcium-binding domains are important to the function of the normal COMP. 相似文献