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At least 55 records · Page 3Linked to original sources
PubMed1998

Risk profile and prediction of long-term ischemic stroke mortality: a 21-year follow-up in the Israeli Ischemic Heart Disease (IIHD) Project.

BACKGROUND: Multinational comparisons demonstrate marked ethnic and regional variation in stroke mortality and risk-factor distribution. We assessed the role of ethnicity and estimated the cumulative effect of multiple risk factors on long-term ischemic stroke mortality. METHODS AND RESULTS: Civil servants and municipal employees in Israel (n=9734 men; age, >/=42 years), chosen by stratified sampling in 6 prespecified areas of birth (those born in Israel and those who were immigrants from 5 other regional-ethnic strata), were included in the Israeli Ischemic Heart Disease (IIHD) Project. Over a 21-year follow-up period, age-adjusted mortality rates per 10 000 person-years attributed to ischemic stroke (n=282; International Classification of Diseases [ICD]-9 codes 433 to 438) were higher among immigrants to Israel from northern Africa and the Mideast (17.1 to 19.0), than from 3 parts of Europe (11.3 to 12.4). Crude rates per 1000 subjects observed in those born in Asia or Africa (29.4 to 31.2) exceeded rates predicted by risk-factor profiles (21.4 to 24.9). Adjusted hazard ratios were 3.00 for age (per 10 years), 2.15 for left ventricular hypertrophy, 1.69 for systolic blood pressure (BP, per 20 mm Hg), 1.86 for diabetes mellitus, 1.83 for peripheral vascular disease, 1.79 for smoking (>20 cigarettes per day), 1.51 for coronary heart disease, 1.16 for percent cholesterol contained in the HDL fraction (%HDL, per 5% decrease), and 1.88 for diastolic BP (per 12 mm Hg; assessed in an alternative model). Accounting for regression dilution bias and assessed from repeat measurements, we found that hazard ratio estimates associated with diastolic BP, systolic BP, and percent HDL (per increments described) increased to 3.22, 2.23, and 1.23, respectively. Ischemic stroke mortality rates were 30-fold greater among subjects at the highest versus the lowest quintile of predicted probability according to risk-factor profiles (81.2 versus 2.6 per 1000 subjects). CONCLUSIONS: Assessment of multiple risk factors provides useful quantitative prediction of long-term ischemic stroke mortality risk. Regional-ethnic variations are consistent with a hypothesis that other, undetermined inherent genetic or sociocultural factors act to increase ischemic stroke mortality rates in immigrants to Israel from the Mideast and northern Africa over that predicted by conventional risk factors.

Adult↗
PubMed2002

HIV infection among people of foreign origin voluntarily tested in Spain. A comparison with national subjects.

OBJECTIVES: To describe exposure categories and HIV prevalence among subjects voluntarily tested in Spain by country of origin. METHODS: HIV prevalence and exposure categories were compared between national and non-Spanish subjects voluntarily tested in 18 sexually transmitted disease/HIV testing clinics from 16 Spanish cities in 2000. RESULTS: Of 8861 testers, 2810 (31.7%) came from foreign countries; 73.1% from Latin America, 9.1% from western Europe, 6.2% from central/eastern Europe, 4.4% from northern Africa, and 4.2% from sub-Sahara Africa. Among women from Latin America, 78% were sex workers compared to 5.5% Spanish women. HIV infection was diagnosed in 170 persons, 34.7% from foreign countries. HIV prevalence for Spanish subjects (23% for men and 1.0% for women) was significantly different from men and women from Latin America (11.3% and 0.3% respectively), Sub-Saharan Africa (9.1% and 7.5% respectively), and women from the north of Africa (11.8%). Compared with Spaniards, analyses of persons of the same exposure category showed higher HIV prevalence in men who had sex with men from Latin America (odds ratio: 4.1; 95% CI: 2.4-6.9), heterosexual men from sub-Sahara Africa (OR: 19.3; 95% CI: 6.4-58.0), and Latin America (OR: 9.4; 95% CI: 3.4-25.9), heterosexual women from sub-Sahara Africa (OR: 16.9; 95% CI: 3.5-82.4) and from northern Africa (OR: 15.3; 95% CI: 3.2-73.2). CONCLUSIONS: An important proportion of HIV testers from these clinics came from foreign countries and some groups showed a high prevalence of HIV infection. Specific prevention and testing programmes adapted to the needs of migrants in Spain should be developed.

Adult↗
PubMed1998

How aspartame prevents the toxicity of ochratoxin A.

The ubiquitous mycotoxin ochratoxin A (OTA) is found as a frequent contaminant of a large variety of food and feed and beverage such as beer, coffee and win. It is produced as a secondary metabolite of moulds from Aspergillus and Penicillium genera. Ochratoxin A has been shown experimentally to inhibit protein synthesis by competition with phenylalanine its structural analogue and also to enhance oxygen reactive radicals production. The combination of these basic mechanisms with the unusual long plasma half-life time (35 days in non-human primates and in humans), the metabolisation of OTA into still active derivatives and glutathione conjugate both potentially reactive with cellular macromolecules including DNA could explain the multiple toxic effects, cytotoxicity, teratogenicity, genotoxicity, mutagenicity and carcinogenicity. A relation was first recognised between exposure to OTA in the Balkan geographical area and Balkan Endemic Nephropathy (BEN) with a high incidence (nearly 50 times higher than normal) of urinary tract tumours. Exposure rates of OTA are measurable in blood of humans and animals and are established in several countries including Scandinavia, Germany, France, Italy, Canada, Japan and Northern Africa mainly Tunisia and Egypt. The impact of OTA exposure in non- endemic areas in the world is not known, the rates of exposure being not correlated with the disease records, especially in developed countries, due to lake of well- designed epidemiological studies, genetic polymorphism and maybe to dietary contents of radical scavengers and antioxidants. However the incidence and mortality rates of renal cancer are increasing in European countries and Northern Africa which could be a global resultant of human exposure to natural compounds in food such as mycotoxins and especially ochratoxin A. In addition to special care to prevent the growth of moulds and detoxification measures there was a need for the prevention of the OTA-induced toxic effects once the toxin is ingested. For this purpose several compound have been studied including some therapeutic agents such as piroxicam which cannot be proposed for a large scale use in humans for preventive purpose. Among other compounds, Aspartame, already used as sweetener has shown a real effectiveness in vivo confirmed largely in vitro. When rats exposed to OTA (289 micrograms/kg) by oral route every two days are given 25 mg/kg similarly for several weeks, all the toxic effects including genotoxicity are very efficiently prevented as shown for example by the disappearance of DNA- adducts in tissues excised from treated animals. Aspartame is also effective in washing out the toxin when given afterwards to animals intoxicated by the same oTA doses for several weeks. In vitro, provided that it is added in cell culture medium before OTA it prevent significantly the inhibition of protein synthesis and lipid peroxidation induced by the toxin. Obviously the molecular mechanism mediating the preventive effect of Aspartame is the delivery of phenylalanine by cleavage of the peptide but also the direct effect of the peptide on the bending capacity and transport of the toxin in vivo and in vitro. As a matter of fact when Aspartame is given to animals or added in culture medium the amount of peptide found unchanged (10-15%) may account for a preventive effect as entire peptide.

Animals↗
PubMed2000

Mutations in the retinoblastoma-related gene RB2/p130 in primary nasopharyngeal carcinoma.

Nasopharyngeal carcinoma (NPC) is an endemic cancer in southern China and northern Africa, and its pathogenesis is not yet well defined at the molecular level. Although the involvement of p53 and of the retinoblastoma gene (RB/p105) in NPC has been well studied, there is paucity of mutational data regarding the retinoblastoma-related gene RB2/p130 in primary tumors and particularly in NPC. We have shown previously that RB2/p130 could be rearranged in a nasopharyngeal cell line. In the present study, we screened by single-strand conformation polymorphism and sequence analysis the retinoblastoma-related gene RB2/p130 for mutations within exons 19-22. Mutations in the RB2/p130 gene were detected in 3 of 10 primary human NPCs from Northern Africa (30%). These findings, along with previous data showing that genetic replacement of RB2/p130 restores a normal growth pathway in the nasopharyngeal cell line Hone-1, strengthen the hypothesis that genetic changes of RB2/p130 may be involved in the development and/or progression of nasopharyngeal cancer and suggest that RB2/p130 could be considered a tumor suppressor gene and may be a candidate for novel gene therapeutic approaches for NPC.

DNA Mutational Analysis↗
PubMed1993

Maternal mortality in Africa: 1980-87.

African women of reproductive age have the highest death risk from maternal causes of any women in the world. The lifetime chance of maternal death is 1 in 21 in Africa as compared to 1 in 54 in Asia, which ranks second. Using published data, this paper examines the level and correlates of maternal mortality ratio (MMR) in Africa. The data indicates that MMR greatly differs among the countries of Africa. High MMR is found in most countries of sub-Saharan Africa, while countries of Northern Africa are characterized by relatively low maternal death. Reasons for high MMR in sub-Saharan Africa are explored in detail. Analysis using multiple regression suggests that the MMR in Africa is strongly influenced by population size, crude birth rate (CBR), crude death rate (CDR), calorie supply as a percentage of requirements, access to safe water, and percentage of urban population. Some cultural and behavioral factors, such as female circumcision and infibulation, are also associated with a high MMR. Future programs aimed at reducing the maternal mortality in African countries may benefit from the findings of this study.

Adolescent↗
PubMed1998

Geographic variation in the molluscan recovery from the end-cretaceous extinction

Biotic recovery patterns after the end-Cretaceous mass extinction differ among the molluscan faunas of the North American Gulf Coast, northern Europe, northern Africa, and Pakistan and northern India. In contrast to the Gulf Coast, the other three regions lack a rapid expansion and decline of "bloom taxa" and have lower proportions of invaders early in the recovery phase. The anomalous Gulf Coast patterns, distinct from extratropical Europe and the tropical regions, provide evidence for the biogeographic and macroevolutionary complexity of biotic recoveries and may have implications for present-day biotas.

Journal Article↗
PubMed1992

Country watch: Benin.

Explore the source record for details and available documents.

Acquired Immunodeficiency Syndrome↗
PubMed1977

[Epidemiological characteristics of water-borne outbreaks of typhoid in North Africa].

On the basis of analysis of several water-borne outbreaks in Northern Africa the authors came to the conclusion that when the population applies for medical aid rarely hospitalization curve reflected the morbidity curve. Attention is paid to the fact that in late and incomplete hospitalization of the patients at the period of water-borne outbreaks of typhoid fever some of the cases are subsequent and are not associated with the factor causing their primary origination. High morbidity indices in older age groups (15-39 years old persons) are due to their greater applicability for medical aid. The group of children aged from 10 to 14 years old is the one affected the most.

Adolescent↗
PubMed1997

Population history of north Africa: evidence from classical genetic markers.

After an intensive bibliographic search, we compiled all the available data on allele frequencies for classical genetic polymorphisms referring to North African populations and synthesized the data in an attempt to reconstruct the populations' demographic history using two complementary methods: (1) principal components analysis and (2) genetic distances represented by neighbor-joining trees. In both analyses the main feature of the genetic landscape in northern Africa is an east-west pattern of variation pointing to the differentiation between the Berber and Arab population groups of the northwest and the populations of Libya and Egypt. Moreover, Libya and Egypt show the smallest genetic distances with the European populations, including the Iberian Peninsula. The most plausible interpretation of these results is that, although demic diffusion during the Neolithic could explain the genetic similarity between northeast Africa and Europe by a parallel process of gene flow from the Near East, a Mesolithic (or older) differentiation of the populations in the northwestern regions with later limited gene flow is needed to understand the genetic picture. The most isolated groups (Mauritanians, Tuaregs, and south Algerian Berbers) were the most differentiated and, although no clear structure can be discerned among the different Arab- and Berber-speaking groups, Arab speakers as a whole are closer to Egyptians and Libyans. By contrast, the genetic contribution of sub-Saharan Africa appears to be small.

Africa, Northern↗