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81.
Interleukin-9 is a cytokine produced by Th2 cells and is a candidate gene for asthma and atopy. We have generated IL-9-deficient mice to delineate the specific roles of IL-9 in Th2 responses. Using a pulmonary granuloma model, we have demonstrated a distinct requirement for IL-9 in the rapid and robust generation of pulmonary goblet cell hyperplasia and mastocytosis in response to lung challenge. In contrast, eosinophilia and granuloma formation were not affected. IL-9 was not required for T cell development or differentiation, the generation of naive or antigen-driven antibody responses, or the expulsion of the intestinal parasitic nematode Nippostrongylus brasiliensis. Thus, deletion of IL-9 manifests as a highly defined phenotype in Th2 responses modulating mucus production and mast cell proliferation. 相似文献
82.
K A Matthews 《Psychosomatic medicine》1992,54(1):1-9
Menopause is a reproductive milestone in a woman's life around which many different myths have developed. We reviewed three sets of myths that middle-aged premenopausal women hold and evaluated those myths according to scientific data from our own work and that of others. First, middle-aged women expect to experience depression, irritability, and vasomotor symptoms during the menopause. It appears that the vast majority of postmenopausal women do not experience depression, but do experience vasomotor symptoms that are uncomfortable and may have secondary effects on psychological well being, especially during the perimenopause. Second, middle-aged women believe that holding negative expectations about the menopause affects the quality of the menopausal experience. Indeed, that appears to be the case, perhaps because myths can function as self-fulfilling prophecy. The third myth is that there are no important changes that occur during the menopause. That is incorrect. Estrogen deficiency during the menopause sets the stage for substantial changes in risk for CHD, which becomes clinically apparent later in life. We discussed how estrogen deficiency may influence both lipids and lipoprotein levels and the magnitude of neuroendocrine and cardiovascular respond to mental stress. That latter pathway is of particular interest because middle-aged women may be exposed more often to interpersonal stress and may respond more emotionally to it, relative to men, suggesting a potential interactive effect of the decline in reproductive hormones and co-occurring social and psychological changes during the menopausal period. This discussion of the myths and realities of the menopause has deliberately not been exhaustive.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
83.
The obstetric outcome of singleton pregnancies following in-vitro fertilization/gamete intra-Fallopian transfer 总被引:1,自引:11,他引:1
Wang Jim X.; Clark Anne M.; Kirby Christine A.; Philipson Gregory; Petrucco Oswald; Anderson Graham; Matthews Colin D. 《Human reproduction (Oxford, England)》1994,9(1):141-146
The present study compares 465 singleton live deliveries fromin-vitro fertilization/gamete intra-Fallopian transfer (IVF/GIFT)pregnancies with a large control population to evaluate theincidence of pre-term delivery and small for gestational age(SGA) or very small for gestation age (VSGA) babies resultingfrom IVF/GIFT pregnancies. Overall the incidence of SGA or VSGAfrom an IVF/GIFT pregnancy is higher than from the normal obstetricpopulation (SGA odds ratio 1.76, 95% confidence interval (CI):1.382.25 and VSGA odds ratio 1.61, 95% CI: 1.052.46)particularly among primiparous women (SGA odds ratio 1.99, 95%CI: 1.253.16 and VSGA odds ratio 1.97, 95% CI: 1.492.62).After stratifying by the cause of infertility, only women withunexplained infertility had a significantly higher proportionof SGA/VSGA babies. There was a significantly higher incidenceof pre-term deliveries among the young primiparae (odds ratio5.02, 95% CI: 3.098.13). Thus the excess risk of deliveringa SGA/VSGA baby and pre-term delivery from an IVF/GIFT pregnancyseems to be largely confined to women with unexplained infertilityand young primiparae. 相似文献
84.
R I Linnoila J L Mulshine S M Steinberg K Funa M J Matthews J D Cotelingam A F Gazdar 《American journal of clinical pathology》1988,90(6):641-652
Bronchial carcinoids and small cell lung cancer (SCLC) are currently recognized as neuroendocrine (NE) neoplasms. However, non-SCLC (NSCLC) may also express NE properties. Paraffin-embedded sections of a comprehensive panel of 113 lung carcinomas were analyzed for the expression of three general markers common to all NE cells, namely, chromogranin A, Leu-7 and neuron-specific enolase (NSE), five specific NE secretory products, and four other tumor markers by immunohistochemistry using the sensitive avidin-biotinylated peroxidase technique. The authors were able to demonstrate the following: (1) most, but not all carcinoids and SCLCs expressed multiple NE markers in a high percentage of tumor cells; (2) up to a half of NSCLC cases contained small subpopulations of cells expressing NE in a high percentage of tumor cells; (2) up to half of NSCLC cases contained small subpopulations of cells expressing NE markers; and (3) occasional NSCLCs showed staining patterns indistinguishable from SCLC. Specifically, 7 of 77 NSCLCs expressed four or more NE markers. NE markers in NSCLCs were more commonly expressed in adenocarcinomas and large cell carcinomas and rarely in squamous cell carcinomas. For comparison, the mean number of NE markers expressed by all cases of NSCLC was 1.5, carcinoids 6.0, and SCLCs 3.8. Individual "marker counts" were not useful in categorizing lung tumors as carcinoids and SCLC versus NSCLC. Instead, 95% of the tumors were correctly classified, applying a statistical model created from staining indices of the three general NE markers (chromogranin A, Leu-7, NSE) and three other tumor markers (carcinoembryonic antigen, keratin, vimentin). Because NSCLCs with NE features might have different clinical characteristics than other NSCLCs, immunohistochemistry provides an effective manner to identify this biologically interesting subset of NSCLCs in routine paraffin sections. 相似文献
85.
Immunoblotting was used to dissect the antibody responses in the sera of 50 patients with proven invasive aspergillosis, 28 patients with suspected invasive aspergillosis, 35 patients with allergic bronchopulmonary aspergillosis, and 10 patients with an aspergilloma. This demonstrated the immunodominance of antigenic bands at 88, 84, 51, and 40 kDa. Monoclonal antibodies against the heat shock protein 90 complexes of Candida albicans and the water mold Achlya ambisexualis identified these four antigenic bands as homologous proteins. Similar antigens have been described in humans, mice, Saccharomyces cerevisiae, chickens, and Drosophila species. The antibody against A. ambisexualis has previously been shown to cross-react with antigens belonging to the human heat shock protein 90 complex. Aspergillus heat shock protein 90 was extracted from the sera of patients with invasive aspergillosis by affinity chromatography. This was done with both a rabbit hyperimmune antiserum raised against an extract of Aspergillus fumigatus NCPF 2109 and a monoclonal antibody against the heat shock protein 90 of C. albicans. In vivo expression of the antigen was demonstrated in an aspergilloma surgically removed from a patient. The role of the antigen as an allergen in allergic bronchopulmonary aspergillosis is also discussed. 相似文献
86.
Oral tonsils: an immunoperoxidase study 总被引:1,自引:0,他引:1
Tissue morphometry and the distribution of cells containing immunoglobulin (Ig), J chain and secretory component (SC) were studied in eight oral tonsils. Quantitative immunohistochemistry revealed that IgG-containing cells predominated in all lymphoid compartments (follicles, extrafollicular areas and reticular epithelium) and that the IgG:IgA:IgM class ratios of the overall tonsillar immunocyte population were 13:8:2. Cells containing IgD and IgE were rare. IgG immunocytes showed no significant localisation within a given lymphoid compartment, whereas IgA cells were found predominantly in extrafollicular areas, especially adjacent to surface epithelium, and IgM cells were in follicles. J chain was present within IgM and some IgA cells. Tonsillar crypt and surface epithelium was negative for SC, suggesting that these structures are not directly involved in local mucosal immunity. 相似文献
87.
Edwin J. Matthews 《Methods in Cell Science》1986,10(3):157-164
Summary The BALB/c-3T3 cell transformation assay evaluates the morphologic transforming potential of test chemicals using cultured mammalian cells as targets. The assay is semiquantitative and employs a contact-inhibited clone of cells derived from the original BALB/c-3T3 mouse cell line. Transforming activity, or a focus, is recognized as a dense layer of morphologically altered cells superimposed on a monolayer of the normal cell phenotype. The induction of transforming activity in a standard assay has been reported to correlate well with the carcinogenicity of many test chemicals in rodent bioassay; however, the standard assay does not detect carcinogens of all chemical classes. This report describes an operational protocol for the standard BALB/c-3T3 cell transformation assay. In addition, it provides assay acceptance criteria and a discussion of a method to evaluate transforming activity data. 相似文献
88.
M Langweiler K J Weinhold T J Matthews D P Bolognesi 《Journal of the National Cancer Institute》1985,74(3):699-704
A 3-methylcholanthrene [(MCA) CAS: 56-49-5]-induced fibrosarcoma cell line and its Friend murine leukemia virus-infected counterpart were assessed for their susceptibility to lysis by so-called "natural" effector cells in a series of 51Cr release assays. Detailed functional and phenotypic analysis of lytic effector cell populations from normal C57BL/6 mouse spleens revealed an identity most closely associated with natural cytotoxic cells. Neither tumor cell line was found to be sensitive to natural killer-mediated lysis. Additionally, virus infection of the MCA-induced fibrosarcoma cell line did not affect susceptibility to natural cell-mediated cytotoxicity. 相似文献
89.
90.
Chandler Cristian J. Meunier Étienne Eaton Lisa A. Andrade Elí Bukowski Leigh A. Matthews Derrick D. Raymond Henry F. Stall Ronald D. Friedman M. Reuel 《Archives of sexual behavior》2021,50(4):1627-1640
Archives of Sexual Behavior - Black men who have sex with men (MSM) engaged in sex work (BMSM-SW) experience elevated HIV and sexually transmitted infection (STI) prevalence. Further, BMSM-SW have... 相似文献