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Casimiro-Lopes G de Oliveira-Junior AV Portella ES Lisboa PC Donangelo CM de Moura EG Koury JC 《Biological trace element research》2009,127(2):109-115
The purpose of this study was to compare plasma leptin, plasma zinc, and plasma copper levels and their relationship in trained
female and male judo athletes (n = 10 women; n = 8 men). Blood samples were obtained 24 h after training to measure plasma zinc, copper, and leptin levels. Subjects presented
similar values to age (22 ± 2 years old), body mass index (24 ± 1 kg/m2), plasma zinc (17.2 ± 2 μmol/L), copper (12.5 ± 2 μmol/L), and leptin (5.6 ± 1.3 μg/L). However, height, total body mass,
lean mass, fat mass, and sum of ten-skinfold thickness were higher in male than female. Plasma leptin was associated with
sum of ten skinfolds in male (r = 0.91; p < 0.001) and female athletes (r = 0.84; p < 0.003). Plasma zinc was associated with leptin in males (r = 0.82; p < 0.05) while copper was associated with plasma leptin in females (r = 0.66; p < 0.05). Our results suggest that young judo athletes lost sex-related differences in leptin levels. Plasma zinc, plasma
copper, and energy homeostasis may be involved in regulation of plasma leptin. 相似文献
124.
Ferry Cornelissen Adriana MC Mus Patrick S Asmawidjaja Jan Piet van Hamburg Joel Tocker Erik Lubberts 《Arthritis research & therapy》2009,11(6):1-13
Introduction
A protein analysis using a mass spectrometry indicated that there are serum proteins showing significant quantitative changes after the administration of infliximab. Among them, connective tissue growth factor (CTGF) seems to be related to the pathogenesis of rheumatoid arthritis (RA). Therefore, this study was conducted to investigate how CTGF is associated with the disease progression of RA.Methods
Serum samples were collected from RA patients in active or inactive disease stages, and before or after treatments with infliximab. CTGF production was evaluated by ELISA, RT-PCR, indirect immunofluorescence microscopy, and immunoblotting. Osteoclastogenesis was evaluated using tartrate-resistant acid phosphatase (TRAP) staining, a bone resorption assay and osteoclasts specific catalytic enzymes productions.Results
The serum concentrations of CTGF in RA were greater than in normal healthy controls and disease controls. Interestingly, those were significantly higher in active RA patients compared to inactive RA patients. Furthermore, the CTGF levels significantly were decreased by infliximab concomitant with the disease amelioration. In addition, tumour necrosis factor (TNF)α can induce the CTGF production from synovial fibroblasts even though TNFα can oppositely inhibit the production of CTGF from chondrocytes. CTGF promoted the induction of the quantitative and qualitative activities of osteoclasts in combination with M-CSF and receptor activator of NF-κB ligand (RANKL). In addition, we newly found integrin αVβ3 on the osteoclasts as a CTGF receptor.Conclusions
These results indicate that aberrant CTGF production induced by TNFα plays a central role for the abnormal osteoclastic activation in RA patients. Restoration of aberrant CTGF production may contribute to the inhibition of articular destruction in infliximab treatment. 相似文献125.
126.
Abstract: The family Phylloporinidae was introduced in the late 19th century to accommodate a small number of Palaeozoic bryozoan genera characterized by irregularly fenestrated colonies generated by anastomosis of unilaminate branches. Among the first named of these genera were Chasmatopora Eichwald, 1855 and Phylloporina Ulrich in Foerste, 1887. The two names have been variously in fashion, and there has been confusion about whether they are subjective synonyms or are distinct genera. This taxonomic confusion has been due in large part to whether the single species (Retepora angulata Hall, 1847) assigned to Phylloporina in Foerste (1887) or the species that Ulrich intended (Retepora trentonensis Nicholson, 1875) is the type species and also because of lack of sufficient information about Foerste’s material to characterize it well. We here redescribe the pertinent species, erect the new species Chasmatopora foerstei for the species that Foerste incorrectly assigned to Phylloporina angulata (Hall), and suggest that Retepora trentonensis Nicholson be retained as type species of Phylloporina based on prevailing usage, until the issue is settled by the International Commission on Zoological Nomenclature. 相似文献
127.
Background
Homology is a crucial concept in comparative genomics. The algorithm probably most widely used for homology detection in comparative genomics, is BLAST. Usually a stringent score cutoff is applied to distinguish putative homologs from possible false positive hits. As a consequence, some BLAST hits are discarded that are in fact homologous. 相似文献128.
129.
Separation of bacterial DNA from human DNA in clinical samples may have an important impact on downstream applications, involving microbial diagnostic systems. We evaluated two commercially available reagents (MolYsis®, Molzym GmbH & Co. KG, Bremen and Pureprove®, SIRS-Lab GmbH, Jena, both Germany) for their potential to isolate and purify bacterial DNA from human DNA. We chose oral samples, which usually contain very high amounts of both human and bacterial cells. Three different DNA preparations each were made from eight caries and eight periodontal specimens using the two reagents above and a conventional DNA extraction strategy as reference. Based on target-specific real-time-quantitative PCR assays we compared the reduction of human DNA versus loss of bacterial DNA. Human DNA was monitored by targeting the β-2-microglobulin gene, while bacteria were monitored by targeting 16S rDNA (total bacteria and Porphyromonas gingivalis) or the glycosyltransferase gene (Streptococcus mutans).We found that in most cases at least 90% of human DNA could successfully be removed, with complete removal in eight of 16 cases using MolYsis, and two (of 16) cases using Pureprove. Conversely, detection of bacterial DNA was possible in all cases with a recovery rate generally ranging from 35% to 50%. In conclusion, both strategies have the potential to reduce background interference from the host DNA which may be of remarkable value for nucleic-acid based microbial diagnostic systems. 相似文献
130.
Adult male Wistar rats were given either a single training trial or one training trial per day during 3 days followed by a retention test trial in an inhibitory avoidance (IA) task. In animals given a single training trial, pretraining, but not pretest bilateral infusion of the NMDA glutamate receptor antagonist d,l-2-amino-5-phosphonopentanoic acid (AP5) (5.0 μg) into the CA1 hippocampal area blocked IA retention. In animals given three training trials, infusions of AP5 given prior to each of the three training trials severely impaired, but did not block retention. The results indicate that NMDA receptors in the hippocampus are involved in the formation, but not in expression, of aversive memory. In addition, rats given repeated training were able to show a mild improvement of performance across training trials, possibly through mechanisms that do not depend on NMDA receptor activation in the dorsal hippocampus. 相似文献