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51.
Podhorec P Socha M Sokolowska-Mikolajczyk M Policar T Svinger VW Drozd B Kouril J 《General and comparative endocrinology》2012,175(1):34-38
Tench (Tinca tinca) is apparently the only known member of the Cyprinidae in which ovulation is stimulated following administration of a low dose of GnRH analogue (GnRHa) without a dopamine inhibitor. This study evaluated LH release effectiveness of the most commonly used GnRHa and clarified whether LH secretion followed by ovulation is subject to inhibitory dopaminergic control in tench. Fish were intraperitoneally injected with three types of GnRHa, GnRHa with dopamine inhibitor metoclopramide (combined treatment), or the dopamine inhibitor metoclopramide alone. LH concentrations at five sampling times (0, 6, 12, 24, and 33 h) together with ovulation success and fecundity index were recorded. The combined treatment triggered an almost immediate LH release peak with a gradual decline, and resulted in a high ovulation rate. In contrast to the combined treatment, an application of GnRHa alone at 10 μg kg(-1) induced gradual increase of LH concentrations with peaks close to ovulation time, and with high ovulation success. Significant differences in LH concentrations at 6 and 12h and no differences in ovulation success were found between the combined and the GnRHa alone treatments. Metoclopramide alone induced a small increase in LH with no ovulation. The study presents clear evidence of dopaminergic control of LH release in tench, with a high ovulation rate obtained after application of GnRHa alone or in combination with dopamine inhibitor. 相似文献
52.
Protein misfolding has been proposed to be a common pathogenic mechanism in many inborn errors of metabolism including cystathionine
β-synthase (CBS) deficiency. In this work, we describe the structural properties of nine CBS mutants that represent a common
molecular pathology in the CBS gene. Using thermolysin in two proteolytic techniques, we examined conformation of these mutants directly in crude cell extracts
after expression in E. coli. Proteolysis with thermolysin under native conditions appeared to be a useful technique even for very unstable mutant proteins,
whereas pulse proteolysis in a urea gradient had limited values for the study of the majority of CBS mutants due to their
instability. Mutants in the active core had either slightly increased unfolding (p.A114V, p.E302K and p.G307S) or extensive
unfolding with decreased stability (p.H65R, p.T191M, p.I278T and p.R369C). The extent of the unfolding inversely correlated
with the previously determined degree of tetrameric assembly and with the catalytic activity. In contrast, mutants bearing
aminoacid substitutions in the C-terminal regulatory domain (p.R439Q and p.D444N) had increased global stability with decreased
flexibility. This study shows that proteolytic techniques can reveal conformational abnormalities even for CBS mutants that
have activity and/or a degree of assembly similar to the wild-type enzyme. We present here a methodological strategy that
may be used in cell lysates to evaluate properties of proteins that tend to misfold and aggregate and that may be important
for conformational studies of disease-causing mutations in the field of inborn errors of metabolism. 相似文献
53.
54.
Taenia taeniaeformis is a globally distributed cestode, which uses felids as definitive and rodents as intermediate hosts. The complete mitochondrial DNA (mtDNA) of T. taeniaeformis from Germany (Tt-GER) was sequenced, and compared with that of another isolate from China (GenBank NC_014768; Tt-CHN), both taken from cats. Analysis of the two mtDNAs indicated that the isolates are significantly different from one another with 12.6% and 9.9% nucleotide and amino acid divergence between them, for concatenated protein-coding genes; overall difference based on a pairwise nucleotide alignment of complete mtDNAs was 11.8%. A phylogenetic analysis based on the 12 protein-coding genes of all available taeniid mtDNAs confirmed the two T. taeniaeformis isolates as sister taxa (likely separate species) and early divergent members of the genus, as suggested previously by morphology. Phylogenetic analysis of published fragments of mt genes rrnS, cox1 and nad1, which represent multiple geographic isolates of T. taeniaeformis also resolve two distinct clades that at present do not seem to be geographically isolated. Mean pairwise (nucleotide) differences between the two clades of T. taeniaeformis were approximately 11%, 10% and 13% in partial rrnS (182bp), cox1 (371bp) and nad1 (459bp) genes, respectively. Differences between entire mtDNAs and partial mt genes of the two T. taeniaeformis isolates are of a similar magnitude between established taeniid sister species. Tt-CHN differs from all other Taenia mtDNAs in lacking a short (~69bp) non-coding region between trnY and trnL1. Partial mt fragment analysis highlighted likely misidentifications of T. taeniaeformis on GenBank. 相似文献
55.
56.
Massari D Prpic-Massari L Kehler T Kastelan M Curkovic B Persic V Ruzic A Laskarin G 《Rheumatology international》2012,32(9):2777-2784
The objective of the present study was to investigate possible changes in granulysin (GNLY)-mediated cytotoxicity of peripheral blood lymphocytes in psoriatic arthritis (PsA) patients with respect to different phases of the disease. We prospectively enrolled 25 PsA patients in the active phase, 26 PsA patients in remission and 24 healthy controls. The simultaneous detection of intracellular GNLY and cell surface antigens (CD3 and CD56) was performed with flow cytometry. GNLY apoptotic protein was visualised by immunocytochemistry. Natural killer (NK) cell cytotoxicity was analysed with a cytotoxicity assay against human erythroleukaemia K-562 cells. The percentage of GNLY(+) cells did not differ significantly between PsA patients in the acute phase and those in remission; however, it was always higher than in healthy examinees due to the increased percentage of GNLY(+) cells within T cells, NKT cells, and both, and in the CD56(+dim) and CD56(+bright) NK subsets. The mean fluorescence intensity for GNLY was higher in all lymphocyte subpopulations in the acute phase than in remission and in healthy controls. Accordingly, GNLY-mediated NK cell cytotoxicity against K-562 cells of active phase PsA patients was significantly higher than that in patients in remission or in healthy controls. These findings demonstrated the involvement of GNLY in the worsening of PsA and suggested that GNLY mediated the development of joint lesions. 相似文献
57.
Tarnoki AD Tarnoki DL Stazi MA Medda E Cotichini R Nisticò L Fagnani C Lucatelli P Boatta E Zini C Fanelli F Baracchini C Meneghetti G Osztovits J Jermendy G Préda I Kiss RG Metneki J Horvath T Karlinger K Racz A Lannert A Molnar AA Littvay L Garami Z Berczi V Schillaci G 《Journal of hypertension》2012,30(8):1564-1571
58.
Tamás Tényi Anikó Somogyi Edina Hamvas Róbert Herold Viktor Vörös Mátyás Trixler 《International journal of psychiatry in clinical practice》2013,17(3):220-222
Objective. The authors report a case during which they observed serious subtypes of induced delusional psychosis (folie communiquée and folie simultanée) without any common genetic background or premorbid psychosis in the case of the secondary patient. Method. The clinical phenomenology of the case is described. Results. Mild intellectual disability and environmental–psychological factors (social isolation and the symbiotic-like interpersonal relatedness) play an essential aetiological role in the case of the secondary recipient patient. Conclusion. The authors emphasize the importance of subclassification of induced delusional psychosis for further aetiological and clinical research. 相似文献
59.
Aron Cseh Kristof Mark Farkas Laszlo Derzbach Katalin Muller Barna Vasarhelyi Balazs Szalay Andras Treszl Viktor Farkas 《Neurological sciences》2013,34(7):1151-1155
Aseptic inflammation due to activated immune cells has been implicated in the pathomechanism of migraine. We measured the prevalence of regulatory T cells (Tregs), along with that of CD4+/CD8+ lymphocytes and their Th1/Th2 commitment in pediatric migraine. Children and adolescents suffering from migraine without aura, migraine with aura and hemiplegic migraine ictally (n = 53, 27, and 20, respectively), also interictally (n = 33) were recruited and compared to 24 healthy children. Our results indicated comparable prevalence of Tregs, CD4+ and Th1/Th2 committed cells. CD8+ prevalence was lower, and CD4+/CD8+ ratio was higher in ictal phase irrespective of the subtype of migraine. No association between CD8+ prevalence and gender, body weight, disease onset and attack duration in migraine subtypes was found. CD8+ prevalence was normal in patients in interictal phase. These results suggest the absence of major systemic alteration of adaptive immunity in children and adolescents suffering from migraine; however, a transient decrease of CD8+ prevalence during the ictal phase was detected irrespective of the subtype of migraine. 相似文献
60.
Autoimmune thrombocytopenic purpura (ITP) is characterized by an abnormally low platelet count and bleeding risks. The exact triggering event remains elusive. Oxidative stress may play a role in several autoimmune diseases. A direct link between platelets in ITP and oxidative stress has not yet been addressed. The intracellular platelet antioxidant capacity (AOC) in ITP patients in the active phase (n?=?24) and remission (n?=?12), and 44 healthy controls were analysed with 2',7'-dichlorodihydrofluorescein diacetate, and in combination with hydrogen peroxide. Enzyme activities (EA) of serum glutathione peroxidase (GPx), glutathione reductase (GRed) and catalase (CAT) were investigated colourimetrically in patients and controls. The AOC of ITP patients in the active phase was drastically reduced, with significantly high mean fluorescence intensity values. Higher GPx activity was observed in both active phase and remission in comparison to healthy controls (p?0.001), with greater activity observed in active ITP than remission (p?=?0.001). However, GRed EA was not elevated indicating that reduced glutathione (GSH) is not comparably recovered as consumed, leading to a decreased bioavailability of GSH and increased oxidative stress. These results suggest that oxidative stress is implicated in active ITP and may play a crucial role in its pathophysiology. 相似文献