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101.
Despite the high prevalence of cervical cancer and cervical neoplasias in South Africa, few studies have been performed in this region to establish which human papillomavirus (HPV) types are associated with the development of high-grade cervical intraepithelial neoplasia lesions and cervical cancer. To investigate these prevalence rates, punch biopsies were obtained from 56 women with cervical cancer and 141 women with histologically diagnosed cervical intraepithelial neoplasia 2 or 3 lesions. Nested polymerase chain reaction (PCR) using consensus degenerate PCR primers was performed for the detection of HPV DNA and HPV typing was done by restriction fragment length polymorphism. Forty-seven (94%) of the cervical cancer and 114 (88%) of the cervical intraepithelial neoplasia 2/3 biopsies were positive for HPV DNA. The prevalence rates of the HPV types detected in the cervical cancer biopsies were HPV 16 (82%), HPV 18, (10%), HPV 33 (10%), HPV 31 (2%), HPV 58 (2%), HPV 35 (2%), and HPV 59 (2%). The cervical intraepithelial neoplasia lesions contained HPV 16 (56.6%), HPV 33 (14%), HPV 31 (10.9%), HPV X (7%), HPV 52 (3.9), HPV 58 (3.1%), HPV 35 (2.3%), HPV 18 (1.6%), HPV 11 (0.8%). Five of the nine fragments that were not typed by the RFLP, designated HPV-X, were sequenced to give HPV6 (1/5), HPV 26 (2/5), HPV 68 (1/5), and candHPV 87 (1/5). HPV 58 was detected in one cervical cancer biopsy and four biopsies from cervical intraepithelial neoplasia grade 3 lesions and was shown to be a previously described variant [Williamson and Rybicki (1991) J. Med. Virol. 33:165-171]. In addition, a cervical intraepithelial neoplasia grade 2 lesion was shown to harbour HPV type HAN2294 (cand HPV 87). The results of this study indicate that cervical cancer and cervical intraepithelial neoplasia 2/3 are largely associated with HPV 16 infection in this group of South African women and, therefore, an effective HPV 16 based vaccine should prevent the development of cervical cancer in a large proportion of women from this region of South Africa.  相似文献   
102.
103.
It has long been suspected that besides their ability to invade enterocytes, enteroinvasive Escherichia coli (EIEC) strains have the ability to elaborate an enterotoxin. We tested 35 EIEC strains for cytotoxins and 9 (1 per serogroup) for enterotoxins. All 35 strains exhibited low levels of Vero cell cytotoxins that are immunologically and genetically distinct from Shiga-like toxin I or II of enterohemorrhagic E. coli. Sterile supernatants and cell lysates of two EIEC strains were tested in rabbit ileal loops, and both stimulated moderate fluid accumulation (circa 0.5 ml/cm) without tissue damage; secretory activity was confirmed in Ussing chambers, where these two strains and the seven others tested significantly increased short circuit current without altering tissue conductance. Curing the 140-MDa invasiveness plasmid from an EIEC strain did not diminish enterotoxin production. Culture in minimal Fe2+ medium is necessary to detect expression of the enterotoxin which is circa 68 to 80 kDa in size and is distinct from the EIEC cytotoxin.  相似文献   
104.
BACKGROUND. Alglucerase (Ceredase) provides effective enzyme-replacement treatment for patients with Gaucher's disease, but at the usually recommended dose of 60 U per kilogram of body weight every two weeks (130 U per kilogram per month), it costs $382,200 per year for a 70-kg patient. Theoretical considerations suggest that more frequent administration would be more efficient. METHODS. Fourteen patients with type 1 Gaucher's disease that was moderately severe to severe were given 30 U of alglucerase per kilogram per month, in divided doses given either daily or three times weekly, or 120 U given three times weekly. The effect of the treatment on the size of the liver and spleen and on blood counts was compared with published data on patients who received a total dose four to five times as large as the lower dose we used and who received treatment every two weeks. RESULTS. The response to 30 U of alglucerase per kilogram per month, fractionated into three or seven doses weekly, was approximately the same as that reported after the administration every two weeks of a dose four or five times as large, given in the large infusions usually recommended. A fourfold increase in the dose given three times weekly, from 2.3 to 9.2 U per kilogram, did not substantially increase the rate of improvement. CONCLUSIONS. The treatment of Gaucher's disease with smaller total doses of alglucerase given more frequently yields satisfactory results. A dose of 2.3 U per kilogram three times weekly yields major financial benefits with no sacrifice of therapeutic effect. Even taking into account the increased ancillary costs of more frequent administration, this method of administering alglucerase reduces the annual cost of the drug for a 70-kg patient to about $100,000.  相似文献   
105.
Leukotriene and prostaglandin production by mouse peritoneal macrophages was investigated. It could be shown that the tumour promoter 12-O-tetradecanoylphorbol-13-acetate initiated the release of prostaglandin E2 but had little effect on the release of leukotriene C4-like immunoreactivity. The divalent cation ionophore A 23187 at concentrations between 10–6 and 10–8 mol/l initiated prostaglandin as well as leukotriene release. This prostaglandin and leukotriene release could be modulated by drugs. Non-steroidal anti-inflammatory drugs including benoxaprofen inhibited prostaglandin release but simultaneously enhanced leukotriene production. The analgesics paracetamol and 4-methylaminoantipyrine had similar effects at high concentrations. The experimental compound BW 755 c inhibited prostaglandin and leukotriene production while the antithrombotic compound nafazatrom inhibited the production of leukotriene C4-like immunoreactivity but enhanced prostaglandin E2 production. Nordihydroguaiaretic acid inhibited prostaglandin and leukotriene production. The results show that the metabolism of arachidonic acid in macrophages via the cyclooxygenase or the lipoxygenase pathway is dependent on the stimulus applied. Both pathways can be inhibited conjointly or selectively by drugs. Our results do not provide evidence that differences in anti-inflammatory activity claimed for some of the drugs tested can be explained by differential inhibition of either pathway. The experimental system described may be used for assessing the potency of drugs to inhibit the lipoxygenase and the cyclooxygenase pathway of arachidonic acid metabolism.  相似文献   
106.
White cell infiltration of solid tumors is an important prognostic indicator in malignant disease. Although macrophage infiltration is associated with good outcome in colorectal cancer, a high macrophage content is associated with poor prognosis in breast cancer. Suppressor macrophages prevent T cell activation in normal tissues such as mucosal linings exposed to continuous antigenic challenge. Interleukin 10 (IL-10), an immunosuppressive cytokine, inhibits macrophage co-stimulation of T cells. Suppressor macrophage numbers, T cell numbers and T cell activation status were assessed in cell suspensions obtained from fresh specimens of breast and colorectal tumours and matched normal tissues. IL-10 production by both malignant and matched normal tissue was also assessed. This study identified elevated numbers of suppressor macrophages in breast tumors compared to matched normal breast tissue. Colorectal tumors did not contain significant numbers of these cells. Although T cell numbers are increased in breast tumors, these cells do not appear to be fully activated, as assessed by major histocompatibility complex class II and Interleukin 2 receptor expression. In contrast, T cells in colorectal tumors exhibit greater expression levels of these markers. Breast tumors produce significantly higher levels of IL-10 than normal breast tissue whereas IL-10 levels in colorectal tumors are similar to normal colon tissue. Our findings of high suppressor macrophage numbers, high levels of IL-10 and poorly activated T cells in breast tumors compared to low suppressor macrophage numbers, low IL-10 and fully activated T cells in colorectal tumors may explain why high macrophage content is associated with poor prognosis in breast cancer and good prognosis in colorectal malignancy.  相似文献   
107.
CD69 is an early activation marker for T cells and cross-linking of CD69 on platelets triggers aggregation and mediator release. Expression of a number of membrane receptors is induced on eosinophils after culture with certain cytokines. Therefore, we investigated whether cytokine-activated eosinophils expressed CD69. Unstimulated, peripheral blood eosinophils did not express CD69, as determined by immunofluorescence and flow cytometry (n = 15). CD69 expression was induced on eosinophils by granulocyte-macrophage colony-stimulating factor (GM-CSF) in a time- and dose-dependent manner. After 1 day in culture, expression was significant at concentrations of 10(-11) M and above. CD69 expression could be detected after stimulation with GM-CSF for only 1 hr, was significant after 2 hr and was sustained over 1-2 days in culture. CD69 expression was also induced by interleukin-3 (IL-3), IL-5 and interferon-gamma (IFN-gamma), but stimulation of eosinophils with platelet-activating factor (PAF) (10(-6) M) for up to 2 hr did not induce CD69 expression. Cycloheximide (10(-6) M) significantly inhibited GM-CSF-induced CD69 expression, suggesting a requirement for protein synthesis. However, unlike up-regulation of CR3 expression, GM-CSF-induced CD69 expression was not inhibited by dexamethasone. CD69 was present on eosinophils from the bronchoalveolar lavage (BAL) fluid of patients with mild asthma (5/5), suggesting that the in vitro findings may have biological relevance in vivo. Therefore, CD69 can be used as a marker of eosinophil activation by cytokines and is a candidate receptor for triggering eosinophil mediator release in the airways in asthma.  相似文献   
108.
Objective : To analyse a ‘socioecological’ health promotion discourse and its relationship to orthodox ‘economistic’ discourse in Australia. Method : In research on health promotion addressing equity and environmental sustainability, we identified a socioecological discourse, based on an ethic of care for people and ecosystems. Using Foucault's concept of discourse as a regime that produces and legitimises certain kinds of knowledge, and ecofeminist historical analysis, we analysed this discourse and its relationship to economism. Results : The socioecological discourse takes social and ecological wellbeing as primary values, while economism takes production and trade of goods and services, measured by money, as primary. Following British invasion, property‐owning white men in Australia had the right to control and profit from land, trade, and the work of women and subordinate peoples. A knowledge regime using money as a primary measure reflects this history. In contrast, a First Nations’ primary value expressed in the study was ‘look after the land and the children’. Conclusion and implications for public health : Public health often attempts to express value through economism, using monetary measures. However, socioecological discourse, expressed for example through direct measures of social and ecological wellbeing, appears more fit for purpose in promoting a fair and sustainable society.  相似文献   
109.
As a philosophical position, pragmatism can be critiqued to distinguish truth only with methods that bring about desired results, predominantly with scientific enquiry. The article hopes to dismiss this oversimplification and propose that within mental health nursing, enquiry enlightened by pragmatism can be anchored to methods helping to tackle genuine human problems. Whilst pragmatists suggest one reality exists, fluctuating experiences and shifting beliefs about the world can inhabit within; hence, pragmatists propose reality has the potential to change. Moreover, pragmatism includes being cognisant of what works to whom reality concerns, making reality context-driven, with a view to understand how actions shape experiences so what is generated has usefulness. Hence, it somewhat follows pragmatism can inform mental health nursing, after all, nursing is a discipline of action, and awareness is needed in how actions produce experiences that patients find helpful. Given the principles of recovery are preferably adopted in mental health care, the paper will explore how pragmatism can help nurses move towards that goal; specifically, with patients voicing their experiences. This is because like pragmatism, recovery subscribes to hope that reality can progress, and through meaningful experiences and beliefs, patients have expertise about personal difficulties alongside how life may flourish, despite mental illness.  相似文献   
110.
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