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91.
92.
Disability pension (DP) is an escalating challenge to individuals and the welfare state, with mental health problems as imminent hazard. The objective of the present paper was to determine if a diagnosis of depression increased the risk of subsequent DP, and whether the risk differed by gender. A population cohort of 1230 persons were diagnostically interviewed (Composite International Diagnostic Interview, CIDI) in a population study examining mental health, linked to the DP registry and followed for 10 years. The risk for DP following depression was estimated using Cox regression. Life‐time depression, as well as current depression, increased the risk of subsequent DP for both genders. The fully adjusted [baseline health, health behavior and socio‐economic status (SES)] hazard ratios (HRs) for life‐time depressed men and women were 2.9 [95% confidence interval (CI) 1.5–5.8] and 1.6 (95% CI 1.0–2.5) respectively. Men were significantly older at time of DP. There are reasons to believe that depression went under‐recognized and under‐treated. To augment knowledge in the field, without underestimating depression as risk for DP, a deeper understanding of the nature and effects of other distress is needed. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
93.
94.
The subtypes of histamine receptors mediating dilatation of human meningeal arteries have been tested in vitro, using "selective" antagonists, and compared with cerebral and temporal arteries previously examined. Dilatory responses were tested after preconstriction with prostaglandin F2 alpha. Both mepyramine and cimetidine caused a parallel shift to the right of the histamine concentration-response curve, suggesting the presence of both H1- and H2-receptors. Combined treatment with mepyramine and cimetidine caused further displacement of the concentration-response curve to the right. Schild analysis indicated pA2 values of 6.3 for cimetidine and 9.8 for mepyramine in situations of near complete blockade of either of the receptors. Both H1- and H2-receptors seem of importance for the histamine-induced dilatation in meningeal arteries and neither appear to dominate. The data considered in conjunction with our previous findings support the finding that experimental histamine-induced headache due to vasodilatation is intracranial of origin.  相似文献   
95.
Background: The long‐term success rates achieved in dental implantology suggest that flexibility might well exist within the various implant systems to a degree that an altered protocol (ie, one‐stage surgery and immediate or early loading) can be performed under controlled conditions. However, before variations of the protocol can be considered for general use, they must be subjected to critical analysis, particularly with respect to the predictability of osseointegration, alteration of soft tissue barrier, and relative change in bone height around the implants. Purpose: The aim of this prospective multicenter study was to evaluate implant survival and periimplant conditions around endosseous implants placed in a one‐stage surgical procedure and early loading. Materials and Methods: A total of 170 implants were placed in 40 patients with mandibular edentulism and were functionally loaded within 6 weeks with overdentures (n = 30) or fixed prostheses (n = 10). All patients and prosthetic constructions were evaluated according to a standardized protocol during 3 years of follow‐up. Cumulative implant survival rates were calculated, and implant loss in relation to implant size and bone quality and quantity were evaluated. Furthermore, the protocol included assessment of clinical (plaque and bleeding scores, prosthesis stability) and radiographic parameters. Results: Over a period of 3 years, the implant survival rate was 93% for both implants and prostheses (fixed or removable). No implants were lost after the first year of loading. The periimplant tissues were in a healthy condition. Mean marginal bone resorption from the time of loading to the 3‐year follow‐up was 0.41 mm (SD 0.52). Conclusions: From this study it may be concluded that early loading results in good implant survival and proper periimplant health in edentulous mandibles.  相似文献   
96.
Jain S  Ohman DE 《Infection and immunity》2005,73(10):6429-6436
The opportunistic pathogen Pseudomonas aeruginosa secretes a capsule-like polysaccharide called alginate that is important for evasion of host defenses, especially during chronic pulmonary disease of patients with cystic fibrosis (CF). Most proteins for alginate biosynthesis are encoded by the 12-gene algD operon. Interestingly, this operon also encodes AlgL, a lyase that degrades alginate. Mutants lacking AlgG, AlgK, or AlgX, also encoded by the operon, synthesize alginate polymers that are digested by the coregulated protein AlgL. We examined the phenotype of an DeltaalgL mutation in the highly mucoid CF isolate FRD1. Generating a true DeltaalgL mutant was possible only when the algD operon was under the control of a LacI(q)-repressed trc promoter. Upon induction of alginate production with isopropyl-beta-D-thiogalactopyranoside, the DeltaalgL mutant cells were lysed within a few hours. Electron micrographs of the DeltaalgL mutant showed that alginate polymers accumulated in the periplasm, which ultimately burst the bacterial cell wall. The requirement of AlgL in an alginate-overproducing strain led to a new model for alginate secretion in which a multiprotein secretion complex (or scaffold, that includes AlgG, AlgK, AlgX, and AlgL) guides new polymers through the periplasm for secretion across the outer membrane. In this model, AlgL is bifunctional with a structural role in the scaffold and a role in degrading free alginate polymers in the periplasm.  相似文献   
97.
BACKGROUND: In the context of mammalian oocyte maturation, it has been suggested that intermediates of cholesterol biosynthesis may represent the physiological signal that instructs the oocyte to reinitiate meiosis. METHODS: Endogenous levels of follicular fluid meiosis-activating sterol (FF-MAS) were monitored in rabbit ovarian tissue, and the influence of exogenous gonadotrophins on sterol formation was assessed. The involvement of cAMP in FF-MAS-induced versus spontaneous oocyte maturation in vitro in mice was also investigated, as was the direct microinjection of FF-MAS into mouse oocytes. RESULTS: Levels of FF-MAS in rabbit ovaries were significantly elevated 1 h after hCG/LH induction and remained so for 4 and 12 h after induction. In naked oocytes undergoing spontaneous maturation, a significant decrease in cAMP was detected after 30 min of culture. However, FF-MAS-mediated induction of oocyte maturation in hypoxanthine-arrested naked oocytes was not associated with any detectable decrease in intracellular cAMP levels. Microinjected FF-MAS failed to induce any noticeable meiosis. CONCLUSIONS: A rapid increase in FF-MAS level occurred in vivo in the rabbit ovary in response to LH, and clear differences were seen in the cAMP pattern during spontaneous and induced oocyte maturation in mice.  相似文献   
98.
Staphylococcus aureus is one of the dominant pathogens that induce septic arthritis in immunocompromised hosts, e.g., patients suffering from rheumatoid arthritis treated with immunosuppressive drugs. S. aureus-induced arthritis leads to severe joint destruction and high mortality despite antibiotic treatment. Recently, interleukin-17A (IL-17A) has been discovered to be an important mediator of aseptic arthritis both in mice and humans, but its function in S. aureus-induced arthritis is largely unknown. Here, we investigated the role of IL-17A in host defense against arthritis following systemic and local S. aureus infection in vivo. IL-17A knockout mice and wild-type mice were inoculated systemically (intravenously) or locally (intra-articularly) with S. aureus. During systemic infection, IL-17A knockout mice lost significantly more weight than the wild-type mice did, but no differences were found in the mortality rate. The absence of IL-17A had no impact on clinical arthritis development but led to increased histopathological erosivity late during systemic S. aureus infection. Bacterial clearance in kidneys was increased in IL-17A knockout mice compared to the level in wild-type mice only 1 day after bacterial inoculation. During systemic S. aureus infection, serum IL-17F protein levels and mRNA levels in the lymph nodes were elevated in the IL-17A knockout mice compared to the level in wild-type mice. In contrast to systemic infection, the IL-17A knockout mice had increased synovitis and erosions and locally decreased clearance of bacteria 3 days after local bacterial inoculation. On the basis of these findings, we suggest that IL-17A is more important in local host defense than in systemic host defense against S. aureus-induced arthritis.Patients with rheumatoid arthritis (RA) are susceptible to bacterial joint infections as a result of immunosuppressive treatments and the disease per se (24). The most common agent causing joint infections is Staphylococcus aureus, a microbe that can also cause sepsis. S. aureus-induced arthritis is a severe problem with a mortality rate of 5 to 20%, and 25 to 70% of affected patients develop permanent joint damage despite treatment (24). Although substantial efforts have been made to understand the immunological mechanisms that lead to S. aureus-induced joint destruction, it remains difficult to treat the infection (by maintaining the host''s ability to clear bacteria) while simultaneously limiting the joint destruction (by suppressing the immunological response). Thus, there is a need to identify new ways to treat RA that do not increase the severity of S. aureus-induced arthritis following infection.Recent evidence from humans and mice suggesting that the proinflammatory cytokine interleukin-17A (IL-17A) is an important player in RA (3, 19, 21) prompted an ongoing clinical trial of IL-17A-blocking antibodies to treat RA (6). Interleukin-17A was first described in 1993, but it was not until 2005, when Harrington et al. (8) described the unique Th17 subset, that the relevance of this cytokine was widely recognized among immunologists (5, 13, 15). Interleukin-17A appears to play a key role in host defense against local Gram-negative extracellular bacterial infections (4, 7, 9, 10, 17, 22, 29, 30) and local S. aureus infections (18) by inducing the production of neutrophil-mobilizing chemokines and growth factors and the subsequent mobilization of neutrophils (5, 13, 15, 16). Importantly, Ishigame et al. have recently shown that genetical knockout of IL-17A plus IL-17F (double knockout) in mice has very little impact on the general outcome of systemic S. aureus infection, measured as mortality and bacterial clearance at a single time point after bacterial inoculation compared with wild-type mice (11). However, in that study, the respective roles of IL-17A and -17F in S. aureus-induced arthritis were not specifically addressed (11), and this aspect is the main focus of this study. S. aureus-induced arthritis is a great concern in RA (24), and the first phase I study using IL-17A-blocking antibodies as a treatment in RA has recently been published (6). Thus, it is clinically important to determine whether reduced IL-17A levels in RA patients would have a detrimental effect on S. aureus-induced arthritis.It is well-known that, within the IL-17 family, IL-17F is the cytokine that shares the greatest structural and functional homology with IL-17A (5, 15). Both IL-17A and IL-17F exist as homodimers or as IL-17A-IL-17F heterodimers and bind to the IL-17 receptor A (IL-17RA)-IL-17RC receptor complex (28). Furthermore, these three IL-17 cytokines may exert similar biological effects, in particular with reference to the local mobilization of neutrophils (23). Studies of healthy mice have also shown that IL-17A is capable of inhibiting the production of IL-17F under certain conditions, through a IL-17RA-dependent mechanism (27). Thus, IL-17A and IL-17F seem to be functionally linked.In the present study, we characterized the kinetics of systemic and local S. aureus infections in the presence and absence of IL-17A in mice. For this purpose, we used IL-17A knockout mice (21) and wild-type control mice in our well-established mouse models of systemic and local S. aureus-induced arthritis (1) and assessed specific aspects of arthritis and more-general clinical outcomes. Using this approach, we obtained evidence that bacterial clearance, cytokine pattern, and degree of arthritis vary over time during systemic S. aureus infection and that IL-17A plays a more important role in local host defense than in systemic host defense against S. aureus-induced arthritis.  相似文献   
99.
Neuroticism has been linked to a functional polymorphism in the serotonin transporter gene (5-HTTLPR), with short-allele carriers being overrepresented among high-scorers on neuroticism. Studies evaluating neuroticism-related personality traits in relation to the 5-HTTLPR polymorphism among patients with premenstrual dysphoric disorder (PMDD) and are lacking. The primary aim of this study was to evaluate the relationship between PMDD and neuroticism-related personality traits, and secondly, to relate the personality trait scores of PMDD patients to experienced symptom severity and to the 5-HTTLPR short allele. Thirty PMDD patients and 55 asymptomatic healthy controls were included in the study. The Swedish Universities Scale of Personality was used to evaluate personality traits. Genotype analyses were available in 27 PMDD patients and 18 healthy controls. Women with PMDD displayed higher levels of neuroticism-related personality traits (psychic trait anxiety, somatic trait anxiety, embitterment, stress susceptibility and mistrust) than healthy controls, and these effects were most prominent in women with more severe luteal phase symptoms. Furthermore, PMDD patients with at least one copy of the short allele of the 5-HTTLPR polymorphism scored higher on psychic trait anxiety and lack of assertiveness than PMDD patients who were homozygous for the long allele. PMDD patients who suffer from more severe luteal phase symptoms also display increased scores of neuroticism-related personality traits in comparison with healthy controls. Within the group of PMDD patients, differences in certain personality trait scores are associated with the short allele of the 5-HTTLPR polymorphism.  相似文献   
100.
Research suggests that when people are fear conditioned to masked spiders and snakes (electric shocks are contingent on only spiders or snakes), they acquire a conditional skin conductance response and can predict the occurrence of shocks even though they are unable to identify the masked spiders and snakes. Because in prior studies trial order was not completely random, it is unclear if findings were due to the contingencies from differential conditioning or a restricted trial order or both. When participants were assigned to four groups to disentangle effects of trial order and differential conditioning to masked pictures in acquisition, effects were obtained only for trial order. These findings demonstrate that trial order can result in conditioning. However, because effects were observed even for participants who reported unawareness of the contingency from trial order, results are consistent with the notion of hunches or gut feelings.  相似文献   
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