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101.
The hyperimmunoglobulinemia D and periodic fever (hyper-IgD) syndrome is typified by recurrent febrile attacks with abdominal distress, joint involvement (arthralgias/arthritis), headache, skin lesions, and an elevated serum IgD level (> 100 U/mL). This familial disorder has been diagnosed in 59 patients, mainly from Europe. The pathogenesis of this febrile disorder is unknown, but attacks are joined by an acute-phase response. Because this response is considered to be mediated by cytokines, we measured the acute-phase proteins C-reactive protein (CRP) and soluble type-II phospholipase A2 (PLA2) together with circulating concentrations and ex vivo production of the proinflammatory cytokines interleukin-1 alpha (IL-1 alpha), IL-1 beta, IL-6, and tumor necrosis factor alpha (TNF alpha) and the inhibitory compounds IL-1 receptor antagonist (IL-1ra), IL-10, and the soluble TNF receptors p55 (sTNFr p55) and p75 (sTNFr p75) in 22 patients with the hyper-IgD syndrome during attacks and remission. Serum CRP and PLA2 concentrations were elevated during attacks (mean, 213 mg/L and 1,452 ng/mL, respectively) and decreased between attacks. Plasma concentrations of IL-1 alpha, IL-1 beta, or IL-10 were not increased during attacks. TNF alpha concentrations were slightly, but significantly, higher with attacks (104 v 117 pg/mL). Circulating IL-6 values increased with attacks (19.7 v 147.9 pg/mL) and correlated with CRP and PLA2 values during the febrile attacks. The values of the antiinflammatory compounds IL-1ra, sTNFr p55, and sTNFr p75 were significantly higher with attacks than between attacks, and there was a significant positive correlation between each. The ex-vivo production of TNF alpha, IL-1 beta, and IL-1ra was significantly higher with attacks, suggesting that the monocytes/macrophages were already primed in vivo to produce increased amounts of these cytokines. These findings point to an activation of the cytokine network, and this suggests that these inflammatory mediators may contribute to the symptoms of the hyper-IgD syndrome.  相似文献   
102.
We describe the development of a human bone marrow (BM) culture system which allows study of the interaction of stromal cell lines (SCL) and highly purified hematopoietic progenitor cells. Normal BM stromal cells were electroporated with a plasmid containing the simian virus 40 (SV40) large T antigen (SV40 T Ag) under the control of a synthetic metallothionein promoter (MT4); this construct is designated MT4 SV40 T Ag. SCL in which the rate of proliferation could be controlled by altering the zinc (Zn) concentration were characterized, demonstrating that the SCL were heterogeneous with respect to G-CSF and GM-CSF production. Suppression of SCL proliferation on removal of Zn made it possible to use these lines in coculture with purified CD34+ progenitor cells from umbilical cord blood. The ability to control proliferation of SCL has allowed us to maintain the survival and expansion of colony- forming cells in culture for up to 2 months. These lines have enabled us to test for stromal cell characteristics at a clonal level and provided us with a tool to analyze the events leading to lineage commitment and hematopoietic differentiation, as demonstrated by suppression of hematopoiesis by an antibody directed against the c-kit molecule.  相似文献   
103.
This report describes the effect of pegylated recombinant human megakaryocyte growth and development factor (PEG-rHuMGDF) on platelet production and platelet function in humans. Subjects with advanced solid tumors received PEG-rHuMGDF daily for up to 10 days. There was no increase in circulating platelet count at doses of 0.03 or 0.1 microgram/kg/d by day 12 of study. At doses of 0.3 and 1.0 microgram/kg/d there was a threefold median increase (maximum 10-fold) in platelet count by day 16. The platelets produced in vivo in response to PEG-rHuMGDF showed unchanged aggregation and adenosine triphosphate (ATP)-release responses in in vitro assays. Tests included aggregation and release of ATP in response to adenosine diphosphate (ADP) (10, 5, 2.5, and 1.25 mumol/L), collagen (2 micrograms/mL), thrombin-receptor agonist peptide (TRAP, 10 mumol/L) and ristocetin (1.5 mg/mL). Administration of aspirin to an individual with platelet count of 1,771 x 10(3)/L resulted in the typical aspirin-induced ablation of the normal aggregation and ATP-release response to stimulation with arachidonic acid (0.5 mg/mL), collagen, and ADP (2.5 and 1.25 mumol/L). There was no change in the expression of the platelet-surface activation marker CD62P (P-selectin) nor induction of the fibrinogen binding site on glycoprotein IIb/IIIa as reported by the monoclonal antibody, D3GP3. An elevation of reticulated platelets was evident after 3 days of treatment with PEG-rHuMGDF and preceded the increase in circulating platelet count by 5 to 8 days; this reflected the production of new platelets in response to PEG-rHuMGDF. At later time points, the mean platelet volume (MPV) decreased in a manner inversely proportional to the platelet count. Levels of plasma glycocalicin, a measure of platelet turnover, rose 3 days after the initial increase in the peripheral platelet count. The level of plasma glycocalicin was proportional to the total platelet mass, suggesting that platelets generated in response to PEG-rHuMGDF were not more actively destroyed. Thus, the administration of PEG-rHuMGDF, to humans, increased the circulating platelet count and resulted in fully functional platelets, which showed no detectable increase in reactivity nor alteration in activation status.  相似文献   
104.
The reproductive capabilities of 6- and 24-month-old C57BL/6NNia male mice were compared after being paired for one month with a 4-month-old proven-fertile female. All of the younger males mated, with 96% yielding a litter; only 42% of aged males mated, with 65% siring young. There were no statistical differences in the litter sizes, nor any congenital defects noted in offspring from either age group. There was no evidence of aneuploidy in 10-day-old embryos sired from males of either age group. Aged males that failed to mate had lower body weight, a lower hematocrit, hypertrophied adrenal glands and seminal vesicles, decreased fructose levels in seminal vesicle fluid, atrophied testes with fewer sperm that were less motile, lower testosterone levels, and a greater percentage of degenerating epithelium lining seminiferous tubules. The latter group of aged mice, while appearing and acting as vigorous as aged mice that had mated, may have been experiencing disease processes associated with aging which subsequently impaired reproduction.  相似文献   
105.
106.
Objective: Many asthma patients suffer from chronic conditions other than asthma. We investigated the specific contribution of common comorbidities on mortality and morbidity in adult asthma. Methods: In an observational study of adults with incident asthma identified between 1999 and 2003 using National Veterans Affairs and Centers for Medicare and Medicaid Services encounter databases (n?=?25?975, follow-up 3.0?±?1.7 years), association between 13 most prevalent comorbidities (hypertension, ischemic heart disease (IHD), osteoarthritis, rheumatoid arthritis, diabetes, mental disorders, substance/drug abuse, enlarged prostate, depression, cancer, alcoholism, HIV and heart failure) and four conditions previously associated with asthma (sleep apnea, gastroesophageal reflux disease (GERD), rhinitis and sinusitis) and mortality, hospitalizations and asthma exacerbations were assessed using multivariate regression analyses adjusted for other clinically important covariates. Results: HIV followed by alcoholism and mental disorders among 18–45-years old, and heart failure, diabetes, IHD and cancer among those ≥65 years old were associated with an increased risk of all-cause mortality. Many conditions were associated with increased risk for all-cause hospitalizations, but the increased risk was consistent across all ages for mental disorders. For asthma exacerbations, mental disorder followed by substance abuse and IHD were associated with increased risk among those 18–45 years old, and chronic sinusitis, mental disorder and IHD among those ≥65-years old. GERD was associated with decreased risk for asthma exacerbation in all ages. Conclusions: Many comorbidities are associated with poor outcome in adult asthmatics and their effect differs by age. Mental disorders are associated with increased risk of mortality and morbidity across ages.  相似文献   
107.
Recently, the Ankylosing Spondylitis Disease Activity Score (ASDAS), a new index, has been shown to be validated and highly discriminatory in assessing ankylosing spondylitis (AS) disease activity. This study is to evaluate the performance of ASDAS in a local Chinese cohort of AS in a cross-sectional setting and to compare it with the existing instrument, the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI). Consecutive patients with AS were recruited from a local rheumatology clinic. Data, including BASDAI, Bath Ankylosing Spondylitis Functional Index (BASFI), Visual Analogue Scale (VAS) for spinal pain, and patient and physician global assessments were gathered during clinic visit. Inflammatory markers, including erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), and high-sensitivity (hs)-CRP were collected. ASDAS was calculated accordingly. The discriminatory capacity of BASDAI and ASDAS was compared by: (1) standardized mean difference statistics, (2) R 2 in linear regressions, and (3) area under receiver operating characteristic curve (AUC) in logistic regression models. Both ASDAS and BASDAI showed satisfactory predictive value on disease activity with reference to patient and physician global assessment. R 2 in linear regression models ranged from 0.6–0.7. Both indices also demonstrated good discriminatory capacity as evidenced by a relatively high AUC (> 0.8) under the logistic regression models using either patient or physician global assessment score ≥4 and <4 as cut off of high and low disease activity status, respectively. Although we could not demonstrate significant differences in the performance between them, subgroup analysis suggested better discriminatory ability of ASDAS in the high inflammatory marker subgroup. ASDAS and BASDAI showed similarly good performance in a cross-sectional setting in a local Chinese AS cohort. ASDAS performed better in subgroup with raised inflammatory markers.  相似文献   
108.
109.

Purpose

Self-rated health (SRH) is widely used to measure and compare the health status of different groups of individuals. However, SRH can suffer from heterogeneity in reporting styles, making health comparisons problematic. Anchoring vignettes is a promising technique for improving inter-group comparisons of SRH. A key identifying assumption of the approach is response consistency—that respondents rate themselves using the same underlying response scale that they rate the vignettes. Despite growing research into response consistency, it remains unclear how respondents rate vignettes and why respondents may not assess vignettes and themselves consistently.

Method

Vignettes for the EQ-5D-5L were developed and included in an online survey. In-depth interviews were conducted with participants following survey completion. Response consistency was examined through qualitative analysis of the interview responses and quantitative coding of participants’ thought processes.

Results

Our analysis showed that anchoring vignettes for the EQ-5D-5L is feasible, but that response consistency may not hold for some participants. Respondents are more likely to rate their own health and vignettes in the same way if presented with overall health state vignettes than single health dimension vignettes, and if they imagined themselves in the health state of the hypothetical individual.

Conclusion

This research highlights opportunities to improve the design of anchoring vignettes in order to enhance response consistency. It additionally provides new evidence on the feasibility of employing anchoring vignettes for the EQ-5D-5L, which is promising for future work to address reporting heterogeneity in the EQ-5D-5L.  相似文献   
110.
Through a one‐pot Friedel–Crafts polymerization method, a series of 8‐hydroxyquinoline‐based polymers with excellent light capturing ability is synthesized to support palladium for light‐driven Suzuki–Miyaura reactions (SMRs). The results of X‐ray powder diffractometer and transmission electron microscopy analyses suggest that the 8‐hydroxyquinoline‐based polymers are amorphous in structure and irregular in morphology. According to the data of thermogravimetric analysis and Brunauer‐Emmett‐Teller gas absorption, they are thermally stable up to 340 °C and are large in specific surface area. With palladium anchored securely on the 8‐hydroxyquinoline units of the polymer skeleton, the obtained photocatalysts exhibit excellent activity and reusability in SMRs under blue‐light irradiation.  相似文献   
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