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71.
BACKGROUND: The nature of histamine-releasing factors involved in the pathogenesis of chronic idiopathic urticaria (CIU) is still controversial, since functional IgG autoantibodies specific for the high-affinity IgE receptor, Fc(epsilon)RI, can be detected in only 20% of patients showing a strong skin reactivity on the autologous serum skin test. The absence of systemic eosinophilia in CIU patients, along with the increase in mast cells in skin biopsy specimens, suggests a possible role for stem cell factor (SCF), the only cytokine/growth factor known to induce mediator release from human mast cells. OBJECTIVE: To investigate the possible role of SCF as a histamine-releasing factor in patients with CIU. METHODS: The SCF levels were measured in serum samples from 65 patients with CIU who scored strongly positive on the autologous serum skin test; of these patients, 32 had negative results and 33 had positive results on in vitro histamine release assay by a quantitative commercial sandwich immunoassay technique. Serum samples from 40 healthy subjects were used as controls. RESULTS: Serum SCF levels in all 65 CIU patients did not differ from those found in healthy controls. No difference in SCF levels was found between patients with positive and negative results on histamine release assay. CONCLUSIONS: An increase in serum SCF levels does not play a pathogenic role in CIU.  相似文献   
72.
Developmental changes in the Ca2+ dynamics of human zygotesand preimplantation embryos were related to changes in the distributionof endoplasmic reticulum (ER) and protein kinase C (PKC). Thefertilization-induced Ca2+ oscillations were typically observedover >5 h, were ryanodine-sensitive and showed a periphery-to-centrepropagation of Ca2+ waves. At the same time, ER and PKC wereaccumulated in the cell periphery. After the appearance of pronuclei,ryanodine-sensitive Ca2+ oscillations of lower amplitude andfrequency were observed until the pronuclear breakdown. However,Ca2+ waves then began in the perinuclear region, in the areaof ER and PKC accumulation and spread towards the cell periphery.During the second to fourth cell cycle, small sinusoidal Ca2+fluctuations were observed; sparse higher-amplitude Ca2+ spikes,superimposed on these basal fluctuations, appeared shortly beforecell division. The sinusoidal Ca2+ fluctuations were asynchronousin individual blastomeres and disappeared progressively in arrestedembryos. The direction of Ca2+ wave propagation and the distributionof ER and PKC were similar to the situation observed in pronuclearzygotes. In contrast to the zygotes, ryanodine did not arrestthe Ca2+ oscillations but augmented their amplitude and frequency.These data suggest that human pre-embryos use different mechanismsof Ca2+ signalling in the early post-fertilization period, duringthe pronuclear development and during cleavage. calcium dynamics/endoplasmic reticulum/human preimplantation embryos/protein kinase C/ryanodine  相似文献   
73.
We report the case of a patient with three synchronous but histologically different primary renal tumors that were all in the same kidney. Two tumors were different subtypes of renal cell carcinoma (RCC), and the third was a variant form of angiomyolipoma. The patient was a 62-year-old man who was receiving antihypertensive drugs and came to our hospital for a regular check-up. Ultrasonography performed during the visit revealed a left renal mass, but the patient had no related symptoms. Subsequent computed tomography revealed two round, high-density masses, one in the mid-portion and the other in the lower pole of the left kidney, and multiple cysts in the right kidney and the liver. The mass in the mid-portion measured 3.3 x 3.0 x 2.8 cm, and the mass in the lower pole measured 1.7 x 1.1 x 0.9 cm. A left radical nephrectomy was performed. On gross examination, an additional ovoid nodule (0.6 cm in the greatest dimension) was found in the lower pole. Microscopically, the largest tumor consisted of a broad alveolar arrangement of large round cells with abundant eosinophilic or clear cytoplasm, distinct cell borders, and perinuclear halos, features consistent with chromophobe RCC. The smallest tumor was a conventional (clear-cell) RCC. The third tumor was composed solely of atypical epithelioid cells with prominent nucleoli and yellowish-brown to black pigments. The tumor cells were positive for melanin (Fontana-Masson stain), the melanoma marker HMB45, vimentin, smooth-muscle actin, and the macrophage marker CD68 and were negative for cytokeratin. This tumor was considered a pigmented epithelioid type of angiomyolipoma. The histologic, histochemical, and immunohistochemical features in this case confirmed the presence of three synchronous primary tumors, a chromophobe and a clear-cell type RCC and a pigmented epithelioid angiomyolipoma, all of which were in the same kidney. This case is the first of its type reported in the literature.  相似文献   
74.
Current Internet-based teleconferencing techniques allow a referring pathologist to transmit real-time images from a microscope to a consultant, while maintaining a verbal conversation using Internet telephony. In our study, 50 randomly selected transbronchial biopsies from lung allograft recipients and 58 randomly selected endomyocardial biopsies from heart transplant patients were diagnosed by consultant pathologists using Internet-based teleconferencing methods. The referring pathologists acquired the real-time video images from the biopsies using a light microscope equipped with a phototube adapter and a video camera. The consultant pathologists viewed the processed images on a video monitor at 800 x 600 resolution, using a standard microcomputer equipped with Netmeeting software, and directed the referring pathologist to move the slide under the microscopy and/or change image magnification. The validity of telepathology diagnoses was assessed with kappa coefficients. Consultations were completed in 5 to 15 minutes per case. Sound transmission was unreliable, and in approximately 25% of consultations the referring pathologist needed to "call back" to reestablish verbal communication. In all but 2 transbronchial biopsies there was agreement between the original diagnosis and the diagnosis by telepathology (kappa = 0.92). In 48 of 58 endomyocardial biopsies there was concordance between the 2 diagnoses (kappa = 0.692). Only 3 out of 10 of these discrepancies were clinically significant (kappa = 0.897). Internet-based teleconferencing techniques provide effective and relatively inexpensive tools for real time telepathology consultations. The technology is probably best suited for the study of small specimens from patients that require rapid diagnosis by a consultant.  相似文献   
75.
After the identification of the interleukin (IL)-1 type II receptor as the prototype, decoy receptors have been identified for a number of members of the IL-1/IL-18, TNF, IL-10 and IL-13 receptor families. Moreover, the silent receptor D6 is a promiscuous decoy and scavenger receptor of inflammatory chemokines. The IL-1 decoy receptor is regulated by pro- and anti-inflammatory signals and its levels may serve as a readout of the activation of anti-inflammatory pathways, for instance by glucocorticoid hormones. Decoy receptors represent a strategy to tune inflammatory and polarized adaptive responses.  相似文献   
76.
77.
Redox control of cell physiology is one of the most important regulatory mechanisms in all living organisms. The thioredoxin system, composed of thioredoxin and thioredoxin reductase, has emerged as a key player in cellular redox-mediated reactions. For many years, only one thioredoxin system had been described in higher organisms, ubiquitously expressed in the cytoplasm of eukaryotic cells. However, during the last decade, we and others have identified and characterized novel thioredoxin systems with unique properties, such as organelle-specific localization in mitochondria or endoplasmic reticulum, tissue-specific distribution mostly in the testis, and features novel for thioredoxins, such as microtubule-binding properties. In this review, we will focus on the mammalian testis-specific thioredoxin system that comprises three thioredoxins exclusively expressed in spermatids (named Sptrx-1, Sptrx-2, and Sptrx-3) and an additional thioredoxin highly expressed in testis, but also present in lung and other ciliated tissues (Txl-2). The implications of these findings in the context of male fertility and testicular cancer, as well as evolutionary aspects, will be discussed.  相似文献   
78.
Postnatal development in the expression of dopamine D1-like and D2-like receptors was investigated in peripheral blood lymphocytes of male Wistar rats aged 1, 3, 4, 8, 12 and 16 weeks of age by radioligand binding assay techniques. Sample of frontal cortex, striatum and hippocampus were also investigated as reference tissues. The dopamine D1-like receptor antagonist [3H]SCH 23390 and the dopamine D2-like receptor agonist [3H]7-OH-DPAT were used as radioligands. The affinity (K(d)) of [3H]SCH 23390 or of [3H]7-OH-DPAT binding was unchanged in lymphocytes of rats of different age groups. The density (B(max)) of [3H]SCH 23390 binding sites increased from the 1st to the 3rd week of age, remained constant from the 3rd to the 8th week of age, and then increased slightly at 12 and 16 weeks of age. The B(max) value of [3H]7-OH-DPAT binding to lymphocytes increased from the 1st to the 3rd week of age, remained constant from the 3rd to the 4th week, increased again until the 12th week and then plateaued. Dopamine D1-like and D2-like receptor maturation in frontal cortex, hippocampus and striatum revealed an increased receptor density until the 4th week of age and a relative stabilization of receptor density values between the 4th to the 12th week depending on the area considered. Comparatively postnatal maturation of lymphocyte dopamine D1-like receptors displayed a pattern different from that of brain areas investigated, whereas maturation of D2-like receptors displayed a pattern similar to that of striatum. The quantitative and/or qualitative dissimilarities between development of lymphocyte and brain dopamine receptors suggest that from a developmental point of view lymphocyte dopamine receptors probably cannot be considered as a marker of homologous brain receptors.  相似文献   
79.
In 18-week-old nulliparous rabbit dose, ovulation was inducedwith 50 IU of pure urinary luteinizing hormone (LH; LHgroup),or 50 IU of ohuman chorionic gonadotrophin (HCG; HCG group),in order to detemine the effect of these treatments on 17-oestradioland progesterone concentrations, and on oocyte and embryo quality.Luteinizing follicles, recovered oocytes, progesteronoe concentrationand grade 5 embryos were significantly reduced when pure urinaryLH was used. Statistically significant correlations were found:(i) between oestradiol concentration and number of degeneratedoocytes in both groups (positive); (ii) between oestradiol concentrationand grade 1 and 2 embrayos (negative), and grade 5 embryos (positive)in the HCG group; (iii) between progesteronoe concentrationand metaphase II oocytes(negatice), and between progesteroneand grade 5 sembryos (positive), in the HCG group; and (iv)between progesterone and oestradiol concentrations (negative)in the LH group. It seems that the oestrsdiol to progegsteroneratio improves during the early luteal phase when ovulationis induced with LH, and that oestradiol and progesterone concentrationscould play a role in dtermining oocyte and embryo quality  相似文献   
80.
Zusammenfassung 4358 männliche Läufer, Teilnehmer am 16-km-Lauf «GP von Bern» 1984, bilden die Studienpopulation einer Querschnittsuntersuchung, in welcher unter anderem die Beziehungen zwischen Jogging und Absentismus analysiert wurden. Die Laufzeit für die 16-km-Strecke und die Zahl der gefehlten Arbeitstage korrelieren positiv (p<0,001); die Laufaktivität (pro Woche im Mittel gelaufene Kilometer) und Absentismus korrelieren entsprechend invers, allerdings nur bis zu einem Trainingsumfang von nicht mehr als ca. 50 km/Woche. Zigarettenrauchende Läufer weisen über 50% mehr Absenzen auf als Nichtrauchende (p<0,001). Zunehmende Bedeutung des Joggingmotivs «als Ausgleich zum Berufsalltag» korreliert invers mit Absentismus (p<0,001), hohe Bedeutung wettkampforientierter Beweggründe für Jogging ist jedoch positiv mit Absentismus assoziiert (p<0,001). Eine multiple Regressionsanalyse mit insgesamt 8 Faktoren vermag lediglich 11% der Varianz der Arbeitsplatzabsenzen zu erklären, was auf die Komplexität der untersuchten abhängigen Variable hindeutet. Die Frage nach der Kausalität der Beziehung zwischen aktivem, regelmässigem (nicht übermässigem) Jogging und erniedrigtem Absentismus bleibt offen. Erst Interventions-studien würden eine bessere Beurteilung des vermuteten Potentials von Bewegung und Sport zur Reduktion von Absentismus erlauben.
Jogging is related to reduced absenteeism (the Berne Grand-prix study'84)
Summary 4358 male runners over age 16, competitors of the 16 km race Grand-prix of Berne 1984, represent the study population of a cross-sectional survey. As a part of it, relationships between jogging and absenteeism were investigated. 16 km running time was positively associated with the number of missed work days (p<0,001); training activity (kilometers run per week, one-year's average) and absenteeism were related in an inverse way, but only up to a training distance of not more than 50 km/wk. Runners who smoked cigarettes missed over 50% more work days than nonsmokers (p<0,001). The relative importance of the motive for jogging as a balance to work was associated with decreased absenteeism (p<0,001), whereas relative importance of competition-orientated motives was associated with increased absenteeism (p<0,001). A multiple regression analysis involving 8 factors was not able to explain more than 11% of the observed variance in missed work days, which underlines the complexity of this dependent variable. The question concerning a possible causal relationship between active, regular, moderate jogging and reduced absenteeism remains unanswered.

Le jogging est associé à un absentéisme réduit (Berner Läuferstudie '84)
Résumé 4358 coureurs agés de 16 ans et plus, participants à la course de 16 km «Grand-Prix de Berne» en 1984, forment l'échantillon d'une étude transversale, à l'occasion de laquelle les relations entre le jogging et l'absentéisme ont également été analysées. Il existe une corrélation positive entre le chronométrage des 16 km et le nombre de jours de travail manqués (p<0,001); en plus, la distance parcourue (moyenne des kilomètres de jogging par semaine) et l'absentéisme sont correlés de façon inverse, mais seulement jusqu'à 50 km d'entraînement hebdomadaire. Les coureurs fumeurs de cigarettes ont plus de 50% d'absences de plus que les coureurs non-fumeurs (p<0,001). L'importance relative du motif pour le jogging «comme compensation au travail journalier» est associée de manière inverse à l'absentéisme (p<0,001), tandis que le contraire est le cas pour l'importance des motifs axés vers la compétition (p<0,001). Une analyse multivariée basée sur un total de 8 facteurs peut expliquer que 11% de la variance de l'absentisme, soulignant ainsi le caractère complexe de la variable dépendente analysée. La question visant la relation causale entre le jogging actif et régulier (mais non exagéré) et un absentisme diminué reste ouverte. Seule des études avec intervention permetteraient de mieux juger le potentiel supposé du sport et de l'activité physique en loisir de réduire l'absentisme.


Der Autor dankt René Rehmann für die Durchführung sämtlicher Datenanalysen, Horst Noack für die kritische Durchsicht des Manuskripts sowie Theres Bietenholz und Christine Vauclair-Liniger für die sekretarielle Hilfe.  相似文献   
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