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1.
The immunoreactivity of various LH and FSH calibration standards and recombinant preparations in the enzyme-linked immunoassay (EIA) systems for gonadotrophins developed for the Special Programme of Research in Human Reproduction of the World Health Organization (WHO) were compared. The preparations tested included three LH and two FSH pituitary standards (calibrated against LH 80/552 and 68/40 and FSH 78/549 respectively) provided with the EIA or radioimmunoassay WHO matched reagent kits, the pituitary preparation LER-907, and recombinant human LH (rhLH) and FSH (rhFSH). Simultaneous curve fitting of the EIA dose-response curves revealed no significant differences among the slopes generated by the WHO LH standards and LER-907; in contrast, no parallelism was found between the curves of rhLH and the pituitary-derived LH standards. No significant differences were found among the slopes of the curves elicited by the pituitary and recombinant FSH preparations. Each LH preparation exhibited a high degree of charge heterogeneity. Considerable variations in charge isoform distribution among the WHO LH standards, rhLH and LER-907 were also evident. In contrast, the FSH preparations were less heterogeneous and exhibited minor differences in charge distribution. Despite the existing differences in charge isoform distribution, all the pituitary-derived preparations as well as rhFSH seem appropriate for using as calibration standards in this particular EIA system.  相似文献   
2.
Vitamin D insufficiency, as measured by 25‐hydroxyvitamin D (25[OH]D) levels, has been associated with important health outcomes. The majority of vitamin D in circulation is bound to vitamin D–binding protein (DBP) and albumin, and recent genetic studies have demonstrated that serum DBP is a major determinant of 25(OH)D concentrations in adults. The impact of circulating DBP levels on vitamin D's biologic action, is unclear, but is of particular relevance to vitamin D epidemiology, because a lack of control for DBP levels could strongly influence the association of vitamin D with disease. Serum parathyroid hormone (PTH) levels can act as a biological readout of 25(OH)D activity. We therefore assessed the relationship between serum total and free 25(OH)D and PTH with and without adjusting for DBP, in 2073 subjects of European descent. Total 25(OH)D levels correlated positively (r = 0.19, p = 1.8 × 10?17) with DBP, whereas the free 25(OH)D correlated negatively (r = ?0.14, p = 5.0 × 10?12). Total and free 25(OH)D levels correlated negatively with PTH (r = ?0.29, p = 1.3 × 10?39; r = ?0.26, p = 1.9 × 10?33, respectively). Including age, body mass index (BMI), sex, estimated glomerular filtration rate, calcium, and season of blood draw as covariates, total 25(OH)D levels were significantly associated with log‐transformed PTH (lnPTH) levels (linear term: β = ?0.010, p < 0.0001, squared term: β = 0.00004, p < 0.0001) and this association was not changed by adjusting for DBP. These findings provide evidence that in a largely vitamin D–sufficient cohort, the biological effect of vitamin D on PTH levels is mainly independent of DBP concentration. Accordingly, this study may provide useful information for studies investigating the relationship between vitamin D, DBP, and disease. © 2014 American Society for Bone and Mineral Research.  相似文献   
3.
Alterations in the reproductive axis function are present to a variable extent in patients with type 1 diabetes mellitus (IDDM). Results from studies in IDDM men have yielded discrepant findings, which may reflect nonuniform patient selection criteria, age, diabetic status, duration of the disease and differences in sampling protocols. To more clearly define the impact of early diabetic alterations in the male reproductive axis, we applied a combined strategy of patient selection restricted to young men with relatively short duration of IDDM, dual control groups, multiparameter deconvolution analysis to assess LH secretory activity, and assessment of time-dependent changes in human chorionic gonadotropin (hCG)-stimulated serum testosterone concentrations. Three groups of subjects were studied: 11 young men with poorly controlled IDDM, 9 well controlled diabetics, and 9 healthy men. All volunteers underwent blood sampling at 10-min intervals before and after 2 consecutive iv pulses of 10 micro g GnRH. On a separate day, 40 IU/kg hCG were given im, and blood samples were collected before hCG administration, every 60 min thereafter for 6 h, and then 24, 48, and 72 h after the injection. Mean serum LH concentrations across the basal 6-h sampling period were significantly (P < 0.05) decreased in men with poorly controlled IDDM (11 +/- 1.6 IU/liter) compared with those in well controlled diabetics (19 +/- 1.8 IU/liter) and healthy controls (19 +/- 1.5 IU/liter). Multiple parameter deconvolution analysis revealed a 50% reduction in the mass of LH secreted per burst and the pulsatile LH secretion rate in poorly controlled IDDM (mass of LH secreted/burst, 7 +/- 1.1 vs. 12 +/- 2.1 and 13 +/- 1.5 IU/liter; LH secretion rate, 47 +/- 6.3 vs. 78 +/- 10 and 87 +/- 11 IU/liter.6 h; poorly controlled vs. well controlled IDDM and healthy controls, respectively; P < 0.05 for both parameters). Uncontrolled IDDM patients had significantly (P < 0.05) lower integrated serum LH concentrations after the first and second GnRH pulses (first GnRH pulse, 4460 +/- 770 vs. 7250 +/- 1200 and 5120 +/- 910 IU/liter; second pulse, 4700 +/- 615 vs. 7640 +/- 881 and 7100 +/- 1230 IU/liter; poorly controlled vs. well controlled IDDM and healthy men, respectively) and markedly attenuated LH secretory burst mass after the second GnRH stimulus (49 +/- 8.8 vs. 90 +/- 13 and 83 +/- 19 IU/liter; poorly controlled vs. well controlled IDDM and healthy controls, respectively). The biological to immunological ratio of LH released in baseline conditions was higher in uncontrolled IDDM patients (0.81 +/- 0.10) than in controlled IDDM (0.37 +/- 0.08) and healthy controls (0.48 +/- 0.06; P < 0.01), whereas LH released in response to exogenous GnRH exhibited comparable ratios among the three study cohorts. Baseline serum testosterone levels as well as absolute and incremental responses to exogenous hCG did not differ by degree of metabolic control. Collectively, these results indicate that the function of the hypothalamic-gonadotrope axis is compromised in young men with poorly controlled IDDM, such that the amplitude of spontaneous pulsatile and exogenous GnRH-stimulated LH secretion is attenuated. This central hypogonadotropism is paradoxically associated with the presence in the circulation of gonadotropin molecules with enriched biological activity, which is evidently sufficient to temporarily maintain normal total testosterone concentrations in the earlier stages of IDDM.  相似文献   
4.
5.
17β-Estradiol (E2) rapidly, by binding to membrane estrogen receptors, activates cell signaling cascades which induce formation of new dendritic spines in the hippocampus of males as in females, but the interaction with other metabolic processes, such as extracellular adenine nucleotides metabolism, are currently unknown. Extracellular adenine nucleotides play significant roles, controlling excitatory glutamatergic synapses and development of neural circuits and synaptic plasticity. Their precise regulation in the synaptic cleft is tightly controlled by ecto-nucleoside triphosphate diphosphohydrolase (NTPDase)/ecto-5′-nucleotidase (eN) enzyme chain. Therefore, we sought to clarify whether a single systemic injection of E2 in male rats is accompanied by changes in the expression of the pre- and postsynaptic proteins and downstream kinases linked to E2-induced synaptic rearrangement as well as alterations in NTPDase/eN pathway in the hippocampal synaptosomes. Obtained data showed activation of mammalian target of rapamycin and upregulation of key synaptic proteins necessary for spine formation, 24 h after systemic E2 administration. In E2-mediated conditions, we found downregulation of NTPDase1 and NTPDase2 and attenuation of adenine nucleotide hydrolysis by NTPDase/eN enzyme chain, without changes in NTPDase3 properties and augmentation of synaptic tissue-nonspecific alkaline phosphatase (TNAP) activity. Despite reduced NTPDase activities, increased TNAP activity probably prevents toxic accumulation of ATP in the extracellular milieu and also hydrolyzes accumulated ADP due to unchanged NTPDase3 activity. Thus, our initial evaluation supports idea of specific roles of different ectonucleotidases and their coordinated actions in E2-mediated spine remodeling and maintenance.  相似文献   
6.
This retrospective study of 100 patients who had surgical treatment for their carpal tunnel syndrome was performed to determine what factors were associated with long-term success or failure. One hundred thirty hands were treated surgically with an average follow-up of 4 years (range, 2 to 6 years). All patients were given a course of conservative treatment that included steroid injection(s) and splinting until the patients were refractory to such therapy. Over 250 injections were given (117 wrists), with the average benefit time of 27 weeks (range 0 to 330). Most patients received two to three injections (maximum of nine). Variables associated with a failure to have long-term benefit after operation included weakness or atrophy of the abductor pollicis brevis muscle, presence of a predisposing condition, and failure to benefit from the initial steroid injection. Conversely, all 51 hands that had relief from median nerve paresthesia for more than 6 months by conservative therapy alone received long-term relief after surgery. Steroids were least effective in hands that had muscle involvement. Fifteen of the 40 hands with muscle involvement regained their muscle mass by the time of the final examination.  相似文献   
7.
Information on the impact of prolonged deficient glycemic control in the quality of the gonadotropin signal delivered by the pituitary gland during puberty in children with insulin-dependent diabetes mellitus (IDDM) is scarce. In the present study, we examined the impact of deficient glycemic control on bioactive LH and FSH concentrations and their corresponding biological-to-immunological (B:I) ratio in boys with poorly controlled, but systemically uncomplicated IDDM. Dual control groups comprising patients with well-controlled IDDM and healthy boys of comparable age and body mass index were included for appropriate comparisons within and between each pubertal stage. Patients with poorly controlled and well-controlled IDDM exhibited serum bioactive FSH levels and B:I FSH ratio similar to those showed by the healthy control group. In contrast, in early and mid-pubertal boys with poorly controlled IDDM bioactive LH levels were normal, but its B:I LH relationship was significantly (P < 0.05) decreased. This attenuation in the quality of the LH signal did not affect total serum T concentrations, and apparently, progression of puberty. Long-standing uncontrolled diabetes and the consequent metabolic disturbances and/or complications may aggravate the reproductive axis dysfunction and eventually provoke pubertal arrest.  相似文献   
8.
Background Human Herpesvirus type 8 (HHV‐8) is a new member of the herpes virus family, first found in the tissue of acquired immune deficiency syndrome (AIDS)‐related Kaposi’s sarcoma. Environmental factors including viral infection may play a role in the onset and/or development of pemphigus. Some studies based on polymerase chain reaction findings suggest an association between HHV‐8 and pemphigus. The aim of this study is investigation of the association of pemphigus with HHV‐8 and the relationship between inflammatory and acantholytic cells with HHV‐8 infection. Methods Tissue‐extracted DNA from 41 paraffin‐embedded skin tissues from patients first presenting with pemphigus was tested using nested PCR for the presence of HHV‐8. A total of 37 cases had pemphigus vulgaris (PV) and 4 patients had pemphigus foliaceus (PF). For our control group, normal skin of 21 cosmetic surgery patients were included. Furthermore, microscopic slides with H&E staining were evaluated for the number of inflammatory and acantholytic cells per microscopic field. Results Skin lesions from 13 of 37 patients (35.1%) with PV and 2 of 4 cases (50%) with PF were positive for HHV‐8 DNA. All specimens in our control group were negative for this virus. Conclusion HHV‐8 infection might be a contributing factor in the initiation or development of pemphigus.  相似文献   
9.
A hermetic seal of the root canal space following canal preparation is important in endodontics. This study evaluated the effect of canal curve on adaptation of gutta-percha to dentinal walls of canals obturated using the Herofill system. For this in vitro study, 80 mesial roots of mature human first molars with length of 16 mm, curve between 5° and 45°, and no caries or resorption of the root surface were selected. A cone beam computed tomography system was used to evaluate the presence or absence of a gap in the samples. Photographs were taken in three sections: 2 mm above the curve, at the curve and 2 mm below the curve. The gap area was identified using Photoshop and AutoCAD software. Kruskal Wallis and Mann-Whitney tests were used to analyze the data mounted in a castcurve. There were significant differences between the two lateral condensation groups with various curves; roots with more curve had more gaps. When the Herofill and lateral condensation groups were compared without considering the sections and curve, there was a significant difference between these groups and the Herofill group had less gaps. The Herofill system is an alternative to the lateral condensation technique in severely curved canals.  相似文献   
10.

Introduction

The purpose of the present study was the immunohistochemical study of fibronectin (FN) and tenascin (TN) in human tooth pulp capped with mineral trioxide aggregate (MTA) and novel endodontic cement (NEC) (calcium enriched mixture cement) after 2 and 8 weeks.

Methods

Thirty-two premolar teeth that were scheduled for extraction for orthodontic reasons were exposed and capped with either MTA or NEC. The teeth were randomly divided into 4 groups: group 1 (NEC for 2 weeks), group 2 (NEC for 8 weeks), group 3 (MTA for 2 weeks), and group 4 (MTA for 8 weeks). After capping the exposed pulps with either NEC (groups 1 and 2) or MTA (groups 3 and 4), half of the specimens underwent extraction and were prepared for histologic and immunohistochemical evaluation for FN and TN after 2 weeks, and the remaining half were assessed after 8 weeks. FN and TN expression was scored by a blinded pathologist on a scale of I-IV, and the results were analyzed by the Wilcoxon and Mann-Whitney U statistical tests.

Results

FN and TN staining was observed in all 4 experimental groups, and there was no significant difference between expression of FN and TN in any groups. FN and TN staining was observed in the dentinal bridge matrix after 2 weeks under MTA. Expression of both markers reduced significantly after 8 weeks under MTA, and staining was observed only in unmineralized parts of dentinal bridge. FN and TN expression was observed in the matrix of the dentinal bridge after 2 weeks under NEC, and staining of both markers was reduced after 8 weeks compared with 2 weeks. The staining pattern of TN in NEC groups was higher than in MTA groups in both time intervals. However, the difference was not significant.

Conclusions

The present study demonstrated that both MTA and NEC are suitable biomaterials for direct pulp capping and are able to stimulate dentinal bridge formation. Moreover, the role of FN and TN as 2 major components of the matrix of a reparative dentinal bridge was observed.  相似文献   
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