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11.
The enzyme-linked immunospot (ELISPOT) assay has been proven to be an efficient and sensitive method for the enumeration of single cells secreting antibodies or cytokines. Here we have used this method to determine the number of interleukin-4 (IL-4)- and interferon-γ (IFN-γ)-producing cells in in vitro secondary responses to tetanus toxoid (TT) and the mycobacterial antigen (purified protein derivative; PPD) or the mitogen phytohemagglutinin (PHA). PHA-induced IL-4 and IFN-γ secretion was well correlated suggesting polyclonal activation of cells. This was not the case with the specific antigens, where PPD preferentially induced IFN-γ- and very few IL-4-producing cells, while TT-induced both IL-4 and IFN-γ. These differences are probably a reflection of the types of immunity the two antigens induce, mycobacteria preferentially inducing a cell-mediated T helper type 1 (Th 1) type of immunity, while immunity to tetanus is an antibody-dependent, Th 2 type of response. In individuals recently boosted with TT, a significant increase in both IL-4- and IFN-γ-producing cells in response to TT was seen at day 7 after boost, followed by decline. This was in contrast to what was seen in response to PPD where an increase of IFN-γ-producing cells after the TT boost at day 7 persisted for at least 14 days. These results suggest that after an in vivo boost both antigen-specific and nonspecific T cells are activated and that antigen-specific cells home to other organs and therefore may be difficult to demonstrate in the circulation. Our data show that the ELISPOT assay is a powerful tool for determining the frequency of cells secreting cytokines. The assay has several advantages over other assays since it is sensitive, measures the number of actually secreting cells, and avoids the problems of binding of cytokines to their cell-bound or soluble receptors.  相似文献   
12.
Piliated and nonpiliated Neisseria gonorrhoeae organisms were added on top of confluent layers of HEC-1-B cells, each maintained on a microporous Transwell-COL membrane. The bacteria released into the lower chamber were characterized with respect to the following virulence determinants: pili, which mediate adherence to target host cells; PilE, the major pilus subunit protein; and PilC, which is involved in pilus biogenesis and adherence. Even if >99% of the added bacteria of N. gonorrhoeae MS11 were piliated, bacteria recovered on the other side of the cell layer were predominantly nonpiliated. The recovered clones still expressed unassembled PilE protein, but 50% had lost PilC production. Nonpiliated gonococci, in which the 5′ end of pilE had been deleted, were released in reduced numbers, and piliated recA bacteria added to the cell layer were not released at all, at time points when piliated recA+ clones were found at high numbers in the lower chamber. Our data indicate that bacteria producing unassembled PilE protein are selected for during passage through an epithelial cell layer. The finding that the pilE gene sequence was altered in the transmigrants suggests that pilin sequence variation is involved in the transcellular passage of N. gonorrhoeae.  相似文献   
13.
Neurotensin (NT)-like peptides in the CNS of the lamprey Lampetra fluviatilis were studied by radioimmunoassay (C-terminal specific NT antiserum), reverse-phase HPLC and immunohistochemistry. Multiple peaks of NT-immunoreactive (-ir) material were observed upon HPLC, of which a major peak eluted in the position of bovine NT. Immunofluorescence histochemistry showed that a monoclonal antibody recognizing the N-terminal (1 - 11) fragment of NT, as well as two polyclonal NT antisera labelled a large number of cell bodies in the periventricular area of hypothalamus, including the postinfundibular commissural nucleus and the ventral and dorsal hypothalamic nuclei. Additional groups of NT-ir cells were observed in the preoptic nucleus, the postoptic commissural nucleus, the mesencephalic tegmentum (L.fluviatilis), and in the spinal cord (L.fluviatilis and Ichtyomyzon unicuspis). Dense NT-ir fibre plexuses were present in the caudal hypothalamus, corpus striatum, ventral mesencephalon, and in the dorsal horn and lateral margin of the spinal cord. At the ultrastructural level the lateral spinal margin showed NT-ir terminal structures, which in most cases were not associated with synaptic specializations, although occasional synaptic contacts with unlabelled elements were found. The relation between NT-ir and monoamine-containing cells was examined with immunofluorescence double-staining, using antisera to tyrosine hydroxylase (TH), 5-hydroxytryptamine (5-HT), and histamine respectively. In the periventricular nuclei of hypothalamus numerous TH-, 5-HT-, as well as histamine-ir cells were located in close association with NT-ir cells, but none of the aminergic markers could be detected within NT-ir neurons. The chemical properties as well as the anatomical distribution of lamprey NT-like peptides show several similarities with those present in mammals, suggesting that NT-containing neuronal systems in the CNS developed early in vertebrate phylogeny.  相似文献   
14.
Summary The 2A-adrenoceptors in rat spleen, kidney, spinal cord and cerebral cortex were studied using [3H]-RX821002 radioligand binding. In the spleen, spinal cord and cerebral cortex, the ligand bound to saturable sites with a K d of about 1 nmol/l and capacities of 134, 240 and 290 fmol/mg protein, respectively. Computer modelling competition curves for 39 drugs, including those for 2A-, 2B- or 2C-adrenoceptor selective drugs, indicated that the sites labelled by [3H]-RX821002 in the spleen consisted of a single population of 2A-adrenoceptors. However, the competition curves for guanoxabenz were definitely biphasic and resolved into two site fits, indicating that guanoxabenz was binding to both high affinity (K d = 35 nmol/1) and low affinity (K d = 8900 nmol/1) 2A-adrenoceptor sites in the proportions 57% and 43%, respectively. The K d Sfor a number of 2-adrenoceptor subtype selective drugs, measured in competition with [3H]-RX821002 in cerebral cortex and spinal cord, were highly correlated with those obtained in the spleen indicating their 2A-adrenoceptor nature. However, by contrast to the results with the spleen, the guanoxabenz competition curves for the spinal cord and cerebral cortex were monophasic and resolved only into one site fits, the K d of guanoxabenz being about 4000 nmol/l for both tissues. Drug K d Sfor kidney 2A-adrenoceptors were also determined using [3H]-RX821002. For nearly all drugs tested, the K d Swere highly correlated with those found for the 2A-adrenoceptors in the other rat tissues. However, for guanoxabenz, the data indicated that it competed with [3H]-RX821002 at a single 2A-adrenoceptor site with a K d of 39 nmol/1. When the rat 2A-adrenoceptor gene RG20 was transiently expressed in COS-7 cells and its ligand binding properties probed using [3H]-RX821002, the drug K d Sobtained were also highly correlated with those found for the 2A-adrenoceptors in the spleen, cerebral cortex, spinal cord and kidney of the rat. For the RG20 encoded receptor, the guanoxabenz competition curves were steep and monophasic and modelled best into one site fits, with the Kd of guanoxabenz being 5200 nmol/1.It is suggested that guanoxabenz can differentiate between two forms of 2A-adrenoceptors in the rat: 2A1 and 2A2. The 2A1-form is present in the spleen and kidney where it shows a high apparent affinity for guanoxabenz. The 2A2-form shows a low apparent affinity for guanoxabenz and is present in the spleen, cerebal cortex and spinal cord. The 2A2-form of the rat 2-adrenoceptor appears to be encoded by the RG20 gene. The 2A, and 2A2-adrenoceptor forms do not represent high and low affinity receptor forms for agonists because assays included EDTA, Gpp(NH)p and Na+, which eliminated the high affinity receptors for agonists.  相似文献   
15.
16.
2-Chloro-2-deoxyadenosine (CdA, Cladribine), is a purine antimetabolite currently under investigation in phase II clinical trials for the treatment of lymphoid malignancies. Significant differences in CdA toxicity between mice and humans were observed during phase I clinical evaluation. For the elucidation of interspecies differences in drug toxicity the pharmacokinetics of CdA after subcutaneous injection and the kinetic properties of the CdA-phosphorylating enzyme, deoxycytidine kinase (dCK), were compared in mice and humans. The ratio of the dose lethal to 10% of mice (LD10) to the maximum tolerated dose (MTD) in humans was 50 and the ratio of the area under the curve obtained at approximately one-half the LD10 (AUCapprox. one-half the LD 10)/AUCMTD was 49. A significant interspecies difference was observed in the kinetic properties of dCK, the main CdA-activating enzyme. With CdA as a substrate, the Michaelis constant (K m) of dCK in crude extracts of mouse thymus was 10 times higher than that in human thymus. An approximately 9-fold interspecies difference in maximum velocity (Vmax)/K m indicated a higher efficiency of dCK for CdA in humans than in mice. The peak plasma concentration was 210 times higher and exceeded theK m in mice. Initial and terminal half-lives were approximately 7 times shorter in mice and trough levels were similar in mice and humans. Thus, the differences in AUCs at equitoxic doses are largely explained by differences in the target enzyme properties and the pharmacokinetic pattern. The observed lower tolerance for CdA in humans as compared with mice confirms the view that antimetabolites may not be good candidates for pharmacokinetically guided dose-escalation schemes unless detailed information on interspecies variability in drug bioactivation is available.  相似文献   
17.
Mammographic screening for breast cancer within health service routines was evaluated for the years 1987–1992, with special focus on repeated screening during 1989–1992. The overall attendance rate by women aged 40 to 74 years was 82.8%. During 1989–1992 malignancy was found in 2.6/1000 screened women, giving a 87.4% positive predictive rate at surgery and 95.9% efficiency. Among women aged 45, the positive predictive rate was >94%. Fine-needle aspiration (FNA) biopsy showed invasive cancers in 84% and highly suspected cancer in another 15%; 60% of the lesions were nonpalpable. For first-time (prevalence) screening (1987–1988) the positive predictive rate was 86% and the malignancy yield 6.4/1000. In women aged 40–44 years there were few surgical referrals (1.6%), but the positive predictive rate at surgery was only 48.3%, indicating diagnostic difficulties in young women. The median size of all invasive cancers was 12 mm: 84% were classified as pT1, and 23% had lymph node involvement. Stage II disease was found in 27% of all malignancies. The use of FNA in the diagnostic workup for breast cancer screening is of crucial importance to the maintenance of high positive predictive rates at surgery. Moreover, regular analysis is important even when mammographic screening is incorporated into the routine work of health services.
Resumen El tamizaje mamográfico para cáncer del seno como parte de las rutinas de los servicios de salud fue evaluado para los años 1987–1992, con especial énfasis en el tamizaje repetido en el período 1989–1992. La tasa de cumplimiento por parte de las pacientes en las edades 40–74 años fue de 82.8%. En 1989–92 se halló neoplasia maligna en 2.6/1000 mujeres tamizadas, lo cual significó un índice de predicción de positividad en la cirugía de 87.4% y de eficiencia de 95.9%. Entre las mujeres con edad 45 años el valor de predicción de positividad fue >94%. La biopsia por aspiración con aguja fina demostró cánceres invasores en 84% y alta sospecha de cáncer en un 15% adicional; 60% de las lesiones fueron no palpables. En el tamizaje de primera vez (prevalencia, 1987–1988) el valor de predicción de positividad fue de 86% y el rendimiento de 6.4/1000. En las mujeres con edades 40–44 años se hicieron menos referencias para cirugía (1.6%) pero el valor de predicción de positividad en la cirugía fue apenas de 48.3%, lo cual indica dificultades diagnósticas en las pacientes más jóvenes. El tamaño promedio de los cánceres invasores fue 12 mm; 84% fueron clasificados como pT1 y 25% presentaban invasión ganglionar; 27% de todos los tumores malignos fueron estado II. La aspiración con aguja fina en la evaluación diagnóstica del tamizaje para cáncer mamario es de importancia crucial para el mantenimiento de un alto valor de predicción de positividad en la cirugía y el análisis regular es importante aun cuando el tamizaje mamográfico quede incorporado en el trabajo rutinario de los servicios de salud.

Résumé Le dépistage systématique des cancers du sein par mammographie effectuée par les services de santé a été évalué entre 1987–1992, en particulier le dépistage répété pratiqué entre 1989–1992. Le taux de participation des femmes âgées entre 40–74 ans a été de 82.8%. Dans la période 1989–1992, une tumeur maligne a été retrouvée chez 2.6/1000 femmes, la chirurgie permettant de calculer une valeur prédictive positive de 87.4% et une efficacité de 95.9%. Chez les femmes âgées de plus de 45 ans, la valeur prédictive positive a dépassé 94%. La ponction biopsie a fourni la preuve de cancer invasif dans 84% des cas et celle d'une forte suspicion dans 15% des cas, alors que 60% des lésions n'étaient pas palpables. Par comparaison, la valeur prédictive positive pendant la période de dépistage entre 1987–88 a été de 96% pour une prévalence de cancer de 6.4/1000. Chez la femme âgée entre 40–44 ans, très peu de femmes ont été opérées, avec une valeur prédictive positive de 48.3%, ce qui démontre les difficultés de diagnostic chez la femme jeune. La taille médiane de tous les cancers invasifs était de 12 mm: 84% étaient classés comme pT1 et 23% avaient un envahissement lymphatique. On a trouvé un stade II chez 27% des patientes tous cancers confondus. L'utilisation de ponction biopsie est capitale pour le diagnostic de cancer de sein pour maintenir une valeur prédictive positive élevée lors de la chirurgie et une analyse régulière est nécessaire même lorsque le dépistage systématique par mammographie est inclu dans le programme des service de santé.
  相似文献   
18.
An X-ray fluorescence (XRF) technique using plane polarized X-rays for excitation was used for in vivo measurements of cadmium in the kidney cortex among non-occupationally exposed members of the general population in southern Sweden. The measured concentrations of cadmium in the kidney cortex of smokers (median 28 g/g, n = 10) were significantly higher (P = 0.0036) as compared to those in non-smokers (median 8 g/g, n = 10), and so were the cadmium concentrations in blood and urine. The results show that smoking considerably increases the cadmium concentration in the kidney cortex and that smoking is a major source of cadmium exposure in the general population of Sweden. Except in the presence of very deeply situated kidneys, where the minimum detectable concentration is high, non-invasive in vivo XRF analysis of kidney cadmium should be a useful tool for evaluating the effects of long-term low-level exposure to cadmium and the risk of kidney damage.  相似文献   
19.
Background: Breast reduction surgery is common in females; however, in males it is mainly due to gynecomastia. After weight reduction following obesity surgery, it is a problem in women, but also in some men. Method: One patient is described in whom the weight reduction declined from BMI 52 to BMI 36 after vertical banded gastroplasty, giving the patient ptotic breasts. Results: The patient underwent reduction mammaplasty with lateral single-based cutaneous flaps, and a total of 1,000 g was removed. Conclusion: Reduction mammoplasty can be performed in males with the methods used today, after successful weight loss following obesity surgery.  相似文献   
20.
OBJECTIVE--The aim was to examine the relationship between social network and activities and causes of death. DESIGN--The study was a prospective cohort study of middle aged men examined in 1973 and followed for 12 years. SETTING--Gothenburg, Sweden. SUBJECTS--The subjects were 769 60 year old and 220 50 year old men who had participated in a health examination. MEASUREMENTS AND MAIN RESULTS--Main outcome measures were mortality from cardiovascular diseases, cancer and other causes. In multivariate analyses cardiovascular mortality was related to baseline blood pressure (p less than 0.001), smoking habits (p = 0.002), myocardial infarction or stroke (p less than 0.001), and a low level of social activities (p = 0.04). Cancer mortality was related to age (p = 0.003) and smoking habits (p = 0.001). Other causes of death were related to poor perceived health (p = 0.02) and a low level of home activities (p = 0.004). In univariate analyses the above risk factors were strongly related to all three causes of death. In addition cardiovascular mortality was related to age, a low level of home and outside home activities, few persons in the household, and poor perceived health. Cancer mortality was related to poor perceived health, few persons in the household, and a low level of social activities. Other causes of death were related to living alone, poor perceived health, and a low level of social and outside home activities. CONCLUSIONS--Well known risk factors for premature mortality like smoking, hypertension, and major cardiovascular disease are verified. Middle aged men with a good "social network" (here measured as a high level of social, home, and outside home activities) may be partly protected against non-cancer mortality.  相似文献   
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