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21.
Blessing Mberu Joyce Mumah Caroline Kabiru Jessica Brinton 《Maternal and child health journal》2014,18(7):1572-1577
Estimates suggest that over 90 % of population increase in the least developed countries over the next four decades will occur in urban areas. These increases will be driven both by natural population growth and rural–urban migration. Moreover, despite its status as the world’s least urbanized region, the urban population in the sub-Saharan Africa region is projected to increase from under 40 % currently to over 60 % by 2050. Currently, approximately 70 % of all urban residents in the region live in slums or slum-like conditions. Sexual and reproductive health (SRH) risks for the urban poor are severe and include high rates of unwanted pregnancies, sexually transmitted infections, and poor maternal and child health outcomes. However, the links between poverty, urbanization, and reproductive health priorities are still not a major focus in the broader development agenda. Building on theoretical and empirical data, we show that SRH in urban contexts is critical to the development of healthy productive urban populations and, ultimately, the improvement of quality of life. We posit that a strategic focus on the sexual and reproductive health of urban residents will enable developing country governments achieve international goals and national targets by reducing health risks among a large and rapidly growing segment of the population. To that end, we identify key research, policy and program recommendations and strategies required for bringing sexual and reproductive health in urban contexts to the forefront of the development agenda. 相似文献
22.
Abdramane Bassiahi Soura Blessing Mberu Patricia Elungata Bruno Lankoande Roch Millogo Donatien Beguy Yacouba Compaore 《Journal of urban health》2015,92(1):39-54
Studies on informal settlements in sub-Saharan Africa have questioned the health benefits of urban residence, but this should not suggest that informal settlements (within cities and across cities and/or countries) are homogeneous. They vary in terms of poverty, pollution, overcrowding, criminality, and social exclusion. Moreover, while some informal settlements completely lack public services, others have access to health facilities, sewers, running water, and electricity. There are few comparative studies that have looked at informal settlements across countries accounting for these contextual nuances. In this paper, we comparatively examine the differences in child vaccination rates between Nairobi and Ouagadougou’s informal settlements. We further investigate whether the identified differences are related to the differences in demographic and socioeconomic composition between the two settings. We use data from the Ouagadougou and Nairobi Urban Health and Demographic Surveillance Systems (HDSSs), which are the only two urban-based HDSSs in Africa. The results show that children in the slums of Nairobi are less vaccinated than children in the informal settlements in Ouagadougou. The difference in child vaccination rates between Nairobi and Ouagadougou informal settlements are not related to the differences in their demographic and socioeconomic composition but to the inequalities in access to immunization services. 相似文献
23.
Carboxybiotin translocation mechanisms suggested by diffraction studies of biotin and its vitamers. 总被引:1,自引:2,他引:1
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G T DeTitta R Parthasarathy R H Blessing W Stallings 《Proceedings of the National Academy of Sciences of the United States of America》1980,77(1):333-337
Biotin is a coenzyme that fixes CO2 for transfer in a family of carboxylase, decarboxylase, and transcarboxylase enzymes. Their enzyme reactions involve two basic steps during which a carboxybiotinyl intermediate forms at one site and translocates to a second (distinct) site for CO2 transfer. Our diffraction studies of biotin and its vitamers suggest that translocation involves rotation about one, or at most two, bonds in biotin's valeryl chain. The rotations are energetically economical gauche in equilibrium trans rotations about the two valeryl bonds nearest the biotin bicyclic ring. They move a carbon atom of a CO2 moiety bound at N-1' approximately 7 A, a distance in accord with spectroscopic measurements of one of the biotin enzymes. From our studies we infer that sulfur in biotin imparts to the valeryl chain a conformational variability necessary for bond rotation and, hence, translocation between catalytic sites. 相似文献
24.
Large colorectal polyps: colonoscopy, pathology, and management 总被引:3,自引:0,他引:3
E J Gyorffy J S Amontree C M Fenoglio-Preiser H K Gogel L D Blessing 《The American journal of gastroenterology》1989,84(8):898-905
Between 1984 and 1987, we reviewed all large (greater than or equal to 3.0 cm) colorectal polyps to determine the efficacy of colonoscopic polypectomy from both an oncologic and technical viewpoint. Forty-eight polyps greater than or equal to 3.0 cm were identified in 46 patients. Twenty polyps were entirely benign, 20 polyps contained noninvasive carcinoma, and invasive carcinoma was present in eight polyps. Four of the invasive cancers were associated with residual adenoma; the remaining four were polypoid carcinomas. Among the eight cases of invasive carcinoma, four had tumors that did not extend through the submucosa. Invasive cancer was more prevalent in left-side sessile lesions but was absent in all 10 right-sided polyps. Thirty-two polyps were removed by colonoscopic polypectomy. Four patients required colectomy after polypectomy for the following reasons: incomplete excision (N = 1), presence of invasive carcinoma at the resection margin (N = 1), and inability to define the level of carcinoma on pathologic examination (N = 2). Two polyps with cancer confined to the submucosa were successfully excised colonoscopically. Complications of polypectomy included three cases of minor hemorrhage. Sixteen polyps (the majority located in the right colon) were removed by primary surgical colectomy. We conclude that colonoscopic polypectomy is oncologically and technically successful for most large colorectal polyps. A minority of large polyps require colectomy because of incomplete removal or the presence of invasive cancer that is not curable with colonoscopic excision. 相似文献
25.
Anthony Hackett Jonathan Stuart Nathan Blessing Nathan Borden 《The American journal of emergency medicine》2018,36(11):2135.e7-2135.e8
Background
Headaches and visual complaints are common conditions encountered in the emergency department. While a patient's age, risk factors, and comorbidities often aid in risk stratification and guide emergency department evaluation, atypical presentations of serious disease may still occur in young otherwise healthy patientsCase
In this vignette we discuss a case of ocular (choroidal) melanoma in a 21?year-old female patient who presented with recurrent photopsia and headaches.Discussion
Ocular melanoma is the most common non-skin melanoma and should be considered by the emergency physician for patients with visual deficits. Likely presentations and risk factors for ocular melanoma will be discussed as well as emergency department and specialty management. 相似文献26.
Christopher Brown Lizeth Lacharme-Lora Blessing Mukonoweshuro Aman Sood Roger B. Newson John Fisher C. Patrick Case Eileen Ingham 《Biomaterials》2013
Metal hip replacements generate both metal particles and ions. The biological effects of peri-articular exposure to nanometre and micron sized cobalt chrome (CoCr) wear particles were investigated in a mouse model. Mice received injections of two clinically relevant doses of nanoparticles (32 nm), one of micron sized (2.9 μm) CoCr particles or vehicle alone into the right knee joint at 0, 6, 12 and 18 weeks. Mice were analysed for genotoxic and immunological effects 1, 4 and 40 weeks post exposure. Nanoparticles but not micron particles progressively corroded at the injection site. Micron sized particles were physically removed. No increase of Co or Cr was seen in peripheral blood between 1 and 40 weeks post exposure to particles. No significant inflammatory changes were observed in the knee tissues including ALVAL or necrosis. DNA damage was increased in bone marrow at one and forty weeks and in cells isolated from frontal cortex at 40 weeks after injection with nanoparticles. Mice exposed to the micron sized, but not nanoparticles became immunologically sensitized to Cr(III), Cr (VI) and Ni(II) over the 40 week period as determined by lymphocyte transformation and ELISpot (IFN-γ and IL-2) assays. The data indicated that the response to the micron sized particles was Th1 driven, indicative of type IV hypersensitivity. This study adds to understanding of the potential adverse biological reactions to metal wear products. 相似文献
27.
Tosin Philip Oyetunji S M Yasir Arafat Stephen Oluwaseyi Famori Timilehin Blessing Akinboyewa Michael Afolami Moyo Faith Ajayi Sujita Kumar Kar 《上海精神医学》2021,34(1)
BackgroundSuicide is a global public health problem and Nigeria is one of the epicentres of suicide in the world. However, there is a dearth of research exploring the epidemiological aspects of suicide in Nigeria.AimTo examine the demographic information and precipitating events for suicides in Nigeria by analysing the contents of newspaper reports of suicide.MethodsWe searched, collected, and analysed published news reports about suicide from 10 English newspapers in Nigeria. A total of 350 suicide reports were assessed between January 2010 and December 2019 after screening and sorting.ResultsThe mean (SD) age of the reported cases was 36.33 (15.48) years. Majority of the reported cases were male (80.6%), married (51.8%), students (33.6%), living in a semi-urban area (40.3%) and among the age group of 25–34 (25.3%). Hanging (48.6%) and poisoning (32.2%) were the most commonly reported methods of suicide. Financial constraints and marital conflicts were most commonly assumed precipitating factors.ConclusionThis study suggests that being male, married, or living in semi-urban areas are associated with suicide in Nigeria. Further community-based studies are warranted to generalise the findings and adopt appropriate preventive strategies. 相似文献
28.
Rapid population growth is a threat to wellbeing in the poorest countries, whereas very low fertility increasingly threatens the future welfare of many developed countries. The mapping of global trends in population growth from 2005-10 shows four distinct patterns. Most of the poorest countries, especially in sub-Saharan Africa, are characterised by rapid growth of more than 2% per year. Moderate annual growth of 1-2% is concentrated in large countries, such as India and Indonesia, and across north Africa and western Latin America. Whereas most advanced-economy countries and large middle-income countries, such as China and Brazil, are characterised by low or no growth (0-1% per year), most of eastern Europe, Japan, and a few western European countries are characterised by population decline. Countries with rapid growth face adverse social, economic, and environmental pressures, whereas those with low or negative growth face rapid population ageing, unsustainable burdens on public pensions and health-care systems, and slow economic growth. Countries with rapid growth should consider the implementation of voluntary family planning programmes as their main policy option to reduce the high unmet need for contraception, unwanted pregnancies, and probirth reproductive norms. In countries with low or negative growth, policies to address ageing and very low fertility are still evolving. Further research into the potential effect of demographic policies on other social systems, social groups, and fertility decisions and trends is therefore recommended. 相似文献
29.
Dopamine D(2)-like receptor agonists cause hypothermia. We investigated whether inhibiting heat production by interscapular brown adipose tissue (iBAT), a major thermogenic organ in rats, contributes to hypothermia caused by dopamine D(2)-like receptor agonists. Temperature of iBAT and tail artery blood flow were measured in conscious rats. Activity in postganglionic sympathetic nerves supplying iBAT was assessed in anesthetized rats. Conscious rats were housed in a warm cage maintained at 26-28 degrees C and then transferred to a cold cage at 5-10 degrees C to induce iBAT thermogenesis. Cold exposure increased iBAT temperature (+0.7+/-0.1 degrees C, 30 min after transferring to the cold cage, P<0.01, n=54). The mixed dopamine D(2)/D(3) receptor agonist, 7-hydroxy-2-(di-n-propylamino)tetralin (7-OH-DPAT, 0.5 mg/kg s.c.) reversed the cold-induced increase in iBAT temperature (-2.8+/-0.2 degrees C at 30 min after 7-OH-DPAT treatment during cold exposure vs. +0.3+/-0.1 degrees C at 30 min after vehicle treatment during cold exposure, n=8). These temperature changes were blocked by pre-treatment with the D(2) receptor antagonists spiperone (20 microg/kg i.p.) and L-741,626 (2.5 mg/kg i.p.), but not by the selective D(3) receptor antagonist SB-277011A (10 mg/kg i.p.). Another mixed dopamine D(2)/D(3) receptor agonist, quinpirole (0.5 mg/kg s.c.) also reversed cold-induced iBAT thermogenesis, and this effect was also prevented by pre-treatment with spiperone, but not with a peripherally acting dopamine receptor antagonist, domperidone (2 mg/kg s.c.). Neither 7-OH-DPAT nor quinpirole reversed cutaneous vasoconstriction elicited by cold exposure. In anesthetized rats, quinpirole (0.5 mg/kg i.v.) abolished iBAT sympathetic nerve discharge elicited by cooling the trunk, and this change was reversed by spiperone (20 microg/kg i.v.). These results demonstrate that activation of CNS dopamine D(2) receptors inhibits sympathetically-mediated iBAT thermogenesis in response to cold exposure. Furthermore, they suggest that in rats hypothermia induced by dopamine D(2) receptor agonists in cold environments is mainly due to decreased heat production rather than to increased heat loss. 相似文献
30.
Herkel J Jagemann B Wiegard C Lazaro JF Lueth S Kanzler S Blessing M Schmitt E Lohse AW 《Hepatology (Baltimore, Md.)》2003,37(5):1079-1085
The ability to activate CD4 T cells is restricted to antigen-presenting cells that express major histocompatibility complex (MHC) class II molecules. Parenchymal cells normally do not express MHC class II molecules; however, in clinical hepatitis, viral or autoimmune, hepatocytes often exhibit aberrant MHC class II expression. It is not known whether MHC class II-expressing hepatocytes can function as antigen-presenting cells, but it has been suggested that aberrant MHC class II expression by parenchymal cells may cause autoimmune disease. Therefore, we generated transgenic mice that specifically overexpress class II transactivator molecules in hepatocytes. Hepatocytes from these mice exhibited stable MHC class II expression and were used to stimulate CD4 T cells from T-cell receptor transgenic mice and CD4 T-cell lines. MHC II-expressing hepatocytes featured costimulatory CD80 molecules and could serve as antigen-presenting cells that were able to process protein antigen and to activate specific CD4 T cells. Nevertheless, the transgenic mice with aberrant hepatocellular MHC class II expression did not exhibit any symptoms of autoimmune disease. In conclusion, MHC II-expressing hepatocytes, as found in clinical hepatitis, can present antigen and activate CD4 T cells. The ability of hepatocytes to present antigen on MHC II molecules does not seem to be a sufficient cause for inflammatory autoimmunity and hepatitis. However, we still need to explore whether such antigen presentation is occurring in vivo. The transgenic mice described in this study may serve as a model to study the immune interaction of hepatocytes and CD4 T cells in both in vitro and in vivo. 相似文献