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11.
A 95-kDa protein was isolated from Staphylococcus saprophyticus 7108 grown on dialysis membranes placed on the surface of brain heart infusion agar. Strain CCM883 did not produce this protein. Ultrathin sections revealed the presence of very thin, tuftlike, 50- to 75-nm-long structures on the surface of strain 7108, whereas strain CCM883 was comparably smooth. The surface material could be removed by digestion with proteinase K, suggesting that the surface structures contain protein. High-resolution scanning electron microscopy showed a thick layer of surface material on strain 7108, whereas strain CCM883 appeared smooth. The 95-kDa protein was purified by Sephacryl S-300 chromatography, and an antiserum was raised in rabbits. This antiserum was used in immunogold labeling experiments, which showed that the protein is associated with the surface structures. Our experiments thus demonstrate the presence of a fibrillar protein on the surface of S. saprophyticus (Ssp for S. saprophyticus surface-associated protein).  相似文献   
12.
13.
Effects of chemical mediators of anaphylaxis on ciliary function   总被引:2,自引:0,他引:2  
We assessed the effects of selected chemical mediators of anaphylaxis on CBF in vitro. Ciliated epithelial cells were obtained from the trachea of conscious sheep with a cytology brush and suspended in a perfusion chamber containing KH. Ciliary activity was viewed microscopically and recorded on videotape for subsequent slow-motion analysis of CBF. Prostaglandin E1 (10(-8) M to 10(-6) M), prostaglandin E2 (10(-10) M to 10(-6) M), and leukotriene-C4 (10(-8) M) increased CBF between 7% and 33%. Histamine caused ciliostimulation only at the relatively high concentrations above 10(-5) M (7% increase in CBF), whereas prostaglandin F2 alpha (10(-10) M and 10(-6) M) was without effect. In no preparation was ciliary discoordination observed. These findings indicate that several chemical mediators of anaphylaxis stimulate CBF and that the previously described impairment of mucociliary transport in stable allergic asthma or antigen-induced bronchoconstriction is probably not caused by a primary alteration of ciliary function.  相似文献   
14.
The effects of two dermatophytes (Microsporum gypseum and Trichophyton mentagrophytes) and four moulds (Scopulariopsis brevicaulis, Alternaria alternata, Geotrichum candidum and Penicillium spp.) on living keratinocyte cultures were examined in vitro using primary human keratinocytes. Rates of apoptosis of infected cells were determined using a colorimetric TUNEL system which detects the characteristic nuclear DNA fragmentation of apoptotic cells. The cytotoxicity of the individual fungi was tested by quantitatively measuring cytosolic enzyme lactate dehydrogenase, released upon cell lysis, in culture supernatants. Additionally, the cell structures within the infected keratinocytes in cultures were examined by scanning electron microscopy. All of the fungi exhibited high cytotoxicity, whereas the development of only the two dermatophytes and the mould Scopulariopsis brevicaulis resulted in distinctly increased apoptosis. Electron microscopy showed that all fungi studied caused similar alterations in the cell structure, with Microsporum gypseum being the most harmful. Increasing loss of cell adhesion as a consequence of a decreasing number of reticulating cell appendices and a reduced cell plasticity were the most evident alterations.  相似文献   
15.
The density dependence of the maximum expiratory flow-volume curve, functional residual capacity (FRC), and specific airway conductance (SGaw) were determined before and during bronchial provocation with ragweed extract in 27 subjects with ragweed hypersensitivity and a history of either bronchial asthma (16 subjects) or allergic rhinitis (11 subjects). Mean baseline SGaw was significantly lower while mean volume of isoflow (Visov) and FrC were significantly higher in subjects with bronchial asthma. During antigen challenge, 10 of 16 subjects with bronchial asthma (63%) and five of 11 subjects with allergic rhinitis (45%) showed a greater than 35% decrease in SGaw ("reactors"): mean relative decreases in SGaw from baseline were 46% and 53%, respectively. The remaining subjects showed a less than 35% decrease in SGaw ("nonreactors") with mean relative decreases of 9% (allergic asthma) and 6% (allergic rhinitis). Mean Visov increased in all subjects with bronchial asthma and in eight of 11 subjects with allergic rhinitis. A significant increase in FRC (6%) was seen only in the "reactors" with bronchial asthma. Following antigen challenge, the beta adrenergic agonist, isoetharine, increased SGaw and decreased Visov. We conclude that in asymptomatic subjects with ragweed hypersensitivity, (1) central and peripheral airway function is more abnormal in subjects with bronchial asthma than in subjects with allergic rhinitis, (2) subjects of both groups show quantitatively and qualitatively comparable airway responses during antigen challenge with a decrease in SGaw or an increase in Visov, possibly representing increase in central and/or peripheral airflow resistance, respectively, (3) Visov may be a more sensitive indicator of airway response to antigen challenge than SGaw, and (4) the bronchodilator effects of a beta adrenergic agonist on antigen-induced bronchospasm are similar in both groups.  相似文献   
16.
This study was designed to investigate the relationship between trunk muscle fatigue and associated changes in the electromyographic (EMG) signals during a dynamic iso-inertial test. Eleven subjects performed dynamic trunk flexion/extension movements against 40% maximum voluntary contraction (MVC) torque until exhaustion in a tri-axial trunk dynamometer. EMG parameters in the time and frequency domain were studied by analysing changes of the signal amplitudes and the spectral density (using the zero-crossing-rate and the median frequency). The kinematics of the movement were analysed according to the movement velocities and the deviations from the required movement plane. The flexion and extension velocities decreased from the beginning to the end of the test. Movement deviations from the sagittal plane into the frontal and transverse plane increased with increasing test duration, as did the EMG amplitude. The median frequency during periods with maximum muscle activity decreased, as did the zero-crossing-rate. The increase in amplitude and decrease in median frequency were more pronounced in the trunk flexors than in the trunk extensors. The parameters of median frequency, zero-crossing-rate and amplitude seem to be sensitive identifiers of muscle fatigue during well-controlled dynamic contractions. While the kinematic data did not yield any information on the mechanisms of the fatigue, changes in the EMG parameters demonstrated that the duration of the test was limited by the fatigue of the trunk flexors.  相似文献   
17.
Parenting stress and parental bonding   总被引:2,自引:0,他引:2  
Attachment experiences are thought to be important because of their implications for later development. The authors' aim with the questionnaire-based study was to investigate the differences between recalled parental bonding regarding 4 types of maternal and paternal bonding with respect to experienced parenting stress caused by child characteristics, parent attributes, and life events under the consideration of the child's gender and age. The authors gathered parental bonding behavior data with the German version of the Parental Bonding Instrument (PBI). The authors assessed parenting stress with their German version of the "Parenting Stress Index (PSI)." They found significant differences among 120 mothers grouped in the 4 maternal and the 4 paternal bonding types regarding parenting stress caused by child, maternal bonding: F(5, 113) = 4.13, p = .002, paternal bonding: F(5, 111) = 8.50, p < or = .0001, and parent characteristics, maternal bonding: F(5, 113) = 3.33, p = .008, paternal bonding: F(5, 111) = 7.80, p < or = .0001. The lowest level of parenting stress was experienced by mothers who themselves recalled the "optimal parental bonding type" with respect to the child and parental domain. The authors did not find any significant differences between the 4 maternal, F(5, 113) = 1.25, p = .29, and the 4 paternal, F(5, 111) = 1.87, p = .106, bonding types with respect to the life stress. According to the authors' findings, the representation of attachment relationships seems to have a special impact on the adult's capacity to cope with challenges and stress, either directly or indirectly as an internal working model of attachment. For the clinical practice, these findings seem to recommend the combination of both the PSI and PBI regarding the diagnostic of stressful mother-child system to plan an optimal intervention program.  相似文献   
18.
Endocrine and metabolic abnormalities following kidney transplantation   总被引:2,自引:0,他引:2  
Summary Various endocrine and metabolic disturbances associated with long standing uremia persist after kidney transplantation or arise from the use of immunosuppressive drugs. Hyperlipidemia for long time being implicated as the cause of corticosteroids is also observed in renal transplant recipients treated with cyclosporin A monotherapy. After conversion from cyclosporin to azathioprine serum cholesterol and triglyceride concentration fall, and elevation of LDL-cholesterol may also be reversed. There is a tendency for higher HDL-cholesterol in azathioprine and prednisolone treated transplant patients. Those patients who are at risk for clinically significant cholesterol elevations can be predicted by their pretransplant lipid levels, specifically the LDL-fraction. Risk-benefit ratio of conversion and of treatment with lipid-lowering drugs, especially with lovastatin, should be carefully examined, also in view of glucose intolerance.Higher incidence of diabetes mellitus requiring insulin therapy in cyclosporin treated transplant recipients has been reported. Cyclosporin may cause toxic effects on pancreatic beta-cells resulting in inhibition of insulin secretion. High doses of cyclosporin induce inhibition of glycogen synthesis in rat liver. Glucose intolerance is reversible after reduction of cyclosporin dose or conversion to azathioprine. Therefore glucose metabolism in kidney transplant recipients treated with cyclosporin should be carefully followed.Immunosuppressive therapy may affect reproductive function, arachidonate metabolism and renin-angiotensin-aldosterone system as well as posttransplant calcium and phophate metabolism.Endocrine and metabolic abnormalities are associated with long standing uremia. After successful kidney transplantation several observations are normalized but further complications arise from the use of immunosuppressive drugs. The present paper reviews various endocrine and metabolic disturbances described following renal transplantation.  相似文献   
19.
Screenings for the genetic disorder alpha(1) antitrypsin deficiency (AAT Deficiency) have been one of two models: large screenings of general populations and small targeted detection programs in high-risk groups. The most appropriate screening and detection methodologies in terms of target populations, subject participation and yield of positive tests, however, have not been well defined. The major objective of this pilot study was to evaluate the effectiveness in terms of participation of two different AAT Deficiency detection programs using a self-administered fingerstick blood test. Individuals ages 30-60 under the care of a pulmonary physician and with a diagnosis of emphysema, COPD, chronic bronchitis, or bronchiectasis were the targeted population. Participants were offered AAT Deficiency testing in the pulmonary physician's office compared with testing offered through mail. Participation (i.e., frequency of subject participation in the detection program) of two different AAT Deficiency detection programs. Non-participation was due to fear of self-administered testing and research studies; women were more likely to participate than men. Eligible subjects were significantly more likely to participate when offered testing by their pulmonary physician in-office (83%) than mail-only (42%) (P < 0.02). Although self-administered genetic testing is available, highest participation in AAT Deficiency detection program was found when offered directly by the physician. This finding may have implications for screening and detection of other genetic diseases. Future studies need to evaluate the yield (i.e., frequency of positive tests) of these detection methodologies in highly targeted populations.  相似文献   
20.
BACKGROUND: Hepatitis B virus (HBV) DNA often remains detectable in serum despite clinical recovery and loss of HBsAg. OBJECTIVE: To study whether coinfection with HIV and HCV influence the chance of detecting HBV DNA in sera with markers of past hepatitis B. STUDY DESIGN AND RESULTS: The test panel included 160 anti-HBc-positive/HBsAg-negative sera collected in the diagnostic setting. The following parameters were determined in the sera: anti-HIV (32% positive), anti-HCV (34% positive), HCV RNA (18% positive), and anti-HBs (37% positive). A highly sensitive PCR (90%-detection limit 100 copies/ml) amplifying the terminal protein (TP) region of HBV was established and HBV DNA was detected in 12.5% of the samples. In 70% of these samples, the HBV DNA concentration was below 500 copies/ml as measured by real-time PCR in the S gene. Logistic regression analysis revealed that the chance of detecting HBV DNA was increased by a positive HCV serostatus (odds ratio 5.0, 95%-CI 1.6-15.7), whereas HIV coinfection (odds ratio 2.0, 95%-CI 0.7-5.8), anti-HBs (odds ratio 0.9, 95%-CI 0.3-2.6), and HCV RNA status (odds ratio 0.4, 95%-CI 0.1-1.7) had no statistically significant influence. In contrast, the chance of detecting HCV RNA in the subgroup of anti-HCV-positive sera was increased by HIV coinfection (odds ratio 4.5, 95%-CI 1.2-17.4). Sequencing of the TP PCR products revealed neither a specific phylogenetic origin of the circulating HBV DNA nor clustering of uncommon mutations in the TP region. CONCLUSIONS: The prevalence of HBV DNA in serum of anti-HBc-positive/HBsAg-negative subjects correlates with HCV rather than HIV serostatus.  相似文献   
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