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71.
Microsporidia of the genus Encephalitozoon are increasingly being reported as a cause of severe, often disseminated infections, mainly in patients with acquired immunodeficiency syndrome (AIDS). Immunological identification of each of the three recognized species (E. cuniculi, E. hellem, and E. intestinalis) requires the availability of specific immune sera. All sera available thus far have been generated by direct inoculation of rabbits with virulent microsporidian spores. This study demonstrates for the first time that subcutaneous immunization with inactivated spores of E. cuniculi, E. hellem, or E. intestinalis is capable of generating highly active rabbit hyperimmune sera to the homologous antigens, with maximal titers being 1:5,120, 1:1,280, and 1:2,560, respectively, as determined by the indirect immunofluorescence technique (IIF). Broad cross-reactivity of the rabbit antisera with all heterologous Encephalitozoon antigens was determined by IIF and immunogold electron microscopy; however, only the E. hellem immune serum strongly cross-reacted with spores of Enterocytozoon bieneusi. During the 35-month follow-up period the antibody titers to the homologous antigens declined to 1:640, 1:160, and 1:320, respectively. The observed decay curves for antibody titers against E. cuniculi, E. hellem, and E. intestinalis were fitted using mathematical modeling, resulting in a predicted duration for specific immune responses of about 7 years on average. Knowledge of the magnitude and duration of specific immune responses is a prerequisite for further evaluation of the concept of using inactivated microsporidian spores in the quest for vaccines against microsporidian infections. Received: 10 April 2000 / Accepted: 18 July 2000  相似文献   
72.
73.
A model showing the topological distribution, functions, and serological specifities of eight distinct, monoclonal antibody-defined epitopes on the tick-borne encephalitis (TBE) virus glycoprotein has been presented in a previous publication [Heinz et al., 1983]. Virology 126, 525–537.) In the present report the influence of conformational change, chemical modification, and fragmentation on the antigenic reactivity of each epitope has been analyzed by the use of blocking enzyme immunoassays and “Western blotting.” One of the two major antigenic domains (A), composed of three different epitopes, completely lost its antigenicity upon incubation at pH 5.0 or by treatment with guanidine-HCl/urea, SDS, reduction and carboxymethylation, as well as by proteolytic (trypsin, α-chymotrypsin, thermolysin) and chemical (CNBr) fragmentation. The second major antigenic domain (B), however, defined by four distinct monoclonal antibodies, three of which are hemagglutination (HA)-inhibiting, neutralizing, and protective, was shown to be resistant to low pH, guanidine-HCl/urea treatment, and proteolytic cleavage of the native protein. Also, polyclonal immune sera from mice and rabbits contained antibody populations reactive with antigenic determinants which are resistant and others which are sensitive to conformational change and fragmentation. Glycoprotein fragments with molecular weights of about 9000, generated by proteolysis of the native protein, were immunoreactive with neutralizing and protective monoclonal antibodies (defining domain B) as well as with a polyclonal mouse immune serum. Thus, these fragments appear to contain antigenic determinants which are immunodominant on the native protein and play an important role in the induction of a protective immune response against TBE virus. In addition, these results show that antibody binding to antigenic domains which are topologically and structurally completely unrelated may result in neutralization and/or HA inhibition. As the presence of two receptor-binding sites is unlikely, different effector mechanisms may account for the effects of these antibodies. The antigenic reactivity of domain A is sensitive to the same treatments which also inactivate HA activity of TBE virus, whereas domain B is resistant. These treatments include a change of domain A induced by incubation at slightly acidic pH which also results in inactivation of virus infectivity. Antibodies to domain A therefore presumably block viral activities by direct binding at or near the putative receptor-binding site whereas antibodies to domain B may cause loss of biological activities by inducing a conformational change of the receptor-binding site.  相似文献   
74.
The anionic polyelectrolytes suramin and Evans Blue inhibited different autolytic systems involved in wall growth and wall turnover of growing staphylococci and in wall autolysis of resting bacteria. Moreover, both substances lowered the beta-lactam-induced pre-lytic release of cytoplasmic constituents from staphylococci, and inhibited the beta-lactam-induced bacteriolysis as well as the loss of viability. The protective effects of these sulfonated drugs against bacteriolysis were also monitored by electron microscopy. Some medical implications of our results are discussed.  相似文献   
75.
The pleiotropic effects of statins, inhibitors of 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase, have been recently extended to the modulation of angiogenesis. Here, to get more insight into the statins action, the authors have investigated the effect of atorvastatin on the expression of several angiogenic and inflammatory genes in human umbilical endothelial cells (HUVECs). Atorvastatin was proangiogenic at the dose of 10 nM, and antiangiogenic at the concentrations of 1 to 10 micro M. Moreover, these higher concentrations inhibited also the proliferation of HUVECs induced by vascular endothelial growth factor (VEGF). Lower doses of atorvastatin did not influence endothelial cell proliferation. Importantly, atorvastatin at the micromolar concentrations diminished the production of interleukin (IL)-8, a proinflammatory and proangiogenic chemokine, and inhibited the synthesis of urokinase plasminogen activator (uPA), a potent proinflammatory mediator. However, it decreased also the expression of plasminogen activator inhibitor-1 (PAI-1) and thrombospondin-1 (TSP-1), the inhibitors of angiogenesis. Atorvastatin stimulated the expression of angiopoietin (Ang)-2 and moderately enhanced the expression of endothelial nitric oxide synthase (eNOS), whereas heme oxygenase-1 (HO-1) was not significantly affected. In conclusion, the present findings points to other angiogenesis-related effects of atorvastatin, which may be of relevance to the beneficial influence of statins in cardiovascular system.  相似文献   
76.
Subjective disability is considered as the variable that reflects the impact of chronic pain on a patient's life. This study examines the questions of which syndrome or patient characteristics determine subjective disability and whether there are differences between samples of patients with chronic headaches and low back pain. Direct pain variables and depression, pain coping strategies, and pain-related self-statements (including catastrophizing) are introduced into multivariate regression analyses as potential predictors of disability using a sample of 151 pain patients. Disability is not predicted by pain severity in patients with headaches or back pain. Psychological variables, especially coping strategies, are far more influential. Coping explains more variance in disability in the headache sample than in the chronic law hack pain group, whereas depression is more relevant for the degree of disability in the back pain sample. In this study, we present a critical analysis of possible interpretations of our results. We point to an overlap of concepts underlying some of the variables used: this overlap also considerably invalidates conclusions drawn from a multitude of studies done in this field, including the one presented. We strongly argue for a conceptual clarification, and consequently for the revision of assessment instruments, before further empirical work in this area is done.  相似文献   
77.
Summary Digital subtraction angiography (DSA) has strongly influenced angiographic procedures. Because it is less invasive it has increased the total number of angiographies in all places where it was introduced. The paper gives an introduction to the procedure explaining the roles of digital and subtraction in DSA. It is written from a technical point of view. The examples are taken from and with the DVI system.  相似文献   
78.
Hamsters in deep experimentally induced hypothermia, at body temperatures between 7 degrees C and 11.5 degrees C, were microinjected with 5-HT and ACh at brain sites in the anterior-preoptic area of the hypothalamus (AH/POA). ACh or 5-HT was injected into an AH/POA site at different starting core temperatures in different groups of hypothermic hamsters. Colonic temperatures (Tc) were maintained, following He-Cold induction, in a temperature controlled environmental chamber and measured with a YSI thermister probe and YSI telethermometer. Injections of either 5-HT or ACh at Tc's between 7.0 degrees C and 9.0 degrees C elicited only modest increases in Tc i.e., 0.3 degrees C--0.6 degrees C, respectively. As Tc increased, however, to ranges between 9.1 degrees C--10.0 degrees C and in different animals to greater than 10 degrees C both ACh and 5-HT at the same sites elicited significant increases in Tc, 1.5 degrees C for 5-HT and 2.2 degrees C for ACh compared to saline injections. These data suggest that at the lowest Tc's we are observing a "cold block" of temperature sensitive sites in the AH/POA. Increasing the starting Tc beyond 9.0 degrees C however, evokes significant increases in heat-gain following AH/POA injection of either ACh or 5-HT. These data are consistent with Myers' observations concerning the organization of heat-gain mechanisms at AH/POA sites. In addition, they suggest that both the afferent limb of the heat-gain circuit (5-HT) and the efferent limb of the circuit (ACh) are functionally impaired when Tc is close to the physiological limit in the He-Cold hypothermic hamster.  相似文献   
79.
To get information about the importance of malrotation for posttraumatic varus or valgus deformity a clinical, radiological and CT follow-up examination of 20 children who were treated for supracondylar fracture from 1983 to 1985 was done. Rotational-displacement was measured on computed tomographical images taken from the region where fracture had happened. On the ap follow-up X-ray from both, the fractured and the other side, and the X-ray which was made after reduction, the medial and lateral colonne were measured from a "special point" in the middle of the shaft of the humerus. The length of the colonnes and their difference were compared. 15 of the 20 patients showed internal malrotation, 1 patient external malrotation and 4 showed no rotational-displacement. In 15 of the 16 patients with malrotation, the rotational-displacement caused a change in the length of the colonnes. Just in one case malrotation caused a minimal deformity of the carrying angle without alteration of the length of the colonnes. 93% of the cases with internal malrotation showed varus deformity. In 3 cases we saw growth disturbance of the epiphyseal plate, but the induced alteration of the length of the colonnes were minimal compared with the changes caused by malrotation.  相似文献   
80.
Zusammenfassung Die Aktion «Gesunde Ernährung» in der Gemeinde-wurde vom Gesundheitsdepartement des Kanton St. Gallen unter der Leitung des kantonalen Präventivmediziners gemeinsam mit den interessierten Gemeinden geplant, koordiniert und durchgeführt.Im Zentrum der Aktion standen gemeindeeigene, individuell gestaltete Aktivitäten von Vereinen, Schulen und des lokalen Gewerbes. Das Gesundheitsdepartement ergänzte die Aktion mit einer Wanderausstellung über Ernährungsfragen, begleitet von einer Ernährungsberaterin. Der Aufbau der Ausstellung erfolgte nach den 10 goldenen Regeln der gesunden Ernährung.Diese Aktion stellt ein konkretes Beispiel der Arbeitsteilung zwischen Kanton und Gemeinde in der Gesundheitsvorsorge dar. Das Beispiel dieser einmaligen Aktion soll Behörden, Vereinen und Einzelpersonen Wege und Methoden aufzeigen, Anliegen der Gesundheitsvorsorge auf längerfristiger Basis in der Gemeinde zu planen.
Healthy Nutrition an experience of health promotion in the county of St. Gall
Summary The drive Healthy Nutrition in communities was planned, co-ordinated und carried out as a joint action by the Health Department of the County of St. Gall, and 37 communities interested in the idea. The drive centred around the activities of the community itself, individuals, clubs, schools and local industry.The County Health Department supplemented the activity with a travelling exhibition about nutrition problems, attended by an advisor to answer questions. The build-up of the exhibition followed the 10 Golden Rules of sound nutrition.This drive was an excellent example of how health-promotion programms can be shared by county und community.This unique action should set an example to other authorities, clubs, and individuals, and show the ways and means needed to provide long-term planning for health promotion in the community.

«Alimentation saine»: le programme du canton de St-Gall
Résumé Un programme «Alimentation saine» a été planifié, coordonné et réalisé en étroite collaboration entre le Service cantonal de médecine préventive et les communes intéressées.Les activités développées par les sociétés locales, les écoles et les commerÇants ont été les éléments essentiels du programme. Le canton a, quant à lui, engagé une diététicienne et mis un bus à disposition ce qui a permis d'organiser une exposition itinérante conÇue selon les 10 règles d'or de l'alimentation saine.Ce programme est une expérience de collaboration entre le canton et les communes pour la promotion de la santé. Il devrait servir d'exemple aux autorités, sociétés locales et individus qui désirent répondre au défi de la promotion de la santé.
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