The epidemiology of primary biliary cirrhosis in southern Israel.
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BACKGROUND: The epidemiology of primary biliary cirrhosis has changed significantly over the last decade, with a trend towards increasing prevalence in many places around the world. OBJECTIVES: To determine the overall prevalence of PBC in southern Israel and the specific rates for different immigrant groups between January 1993 and October 2004. METHODS: Multiple case-finding methods were used to identify all cases of PBC in the study region. Age-adjusted prevalence rates were compared among the different immigrant groups. RESULTS: A total of 47 cases of PBC were identified with an overall prevalence of 55 cases per million. All patients were women, and all except for a Bedouin Arab were Jewish. Foreign-born patients comprised 70% of our PBC cohort even though they represent only 45.4% of the regional population. This predominance of immigrants did not change when the rates were adjusted for age (P < 0.001). The prevalence rates were 40, 177, and 58 cases per million for those born in Israel, North Africa or Asia, and Eastern Europe, respectively. The age-specific prevalence rate for women older than 40 years varied from 135 cases per million among those born in Israel to 450 among immigrants from Eastern Europe and the former USSR to 700 cases per million among immigrants from North Africa and Asia. CONCLUSIONS: The prevalence of PBC in southern Israel is similar to that reported from some European countries. The rate is much higher among Jews than Arabs and among immigrants to Israel compared to native Israelis. (+info)
Taxonomy and chemical characterization of antibiotics of Streptosporangium Sg 10 isolated from a Saharan soil.
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A new actinomycete strain designated Sg 10, producing antimicrobial substances was isolated from an Algerian soil. Morphological and chemical studies indicated that strain Sg 10 belonged to the genus Streptosporangium. The comparison of its physiological characteristics with those of known species of Streptosporangium showed significant differences with the nearest species Streptosporangium carneum. Analysis of the 16S rDNA sequence of strain Sg 10 showed a similarity level ranging between 96.3% and 97.8% within Streptosporangium species, with S. carneum the most closely related. However, the phylogenetic analysis indicated that strain Sg 10 represent a distinct phyletic line suggesting a new genomic species. The antimicrobial activity of strain Sg 10 showed an antibacterial activity against Gram-positive bacteria as well as an antifungal one. Four active products were isolated from the culture broth using various separation procedures. On the basis of UV-VIS spectrometry, infrared spectroscopy and chemical revelations, the antibiotics were classified in the group of glycosylated aromatics. (+info)
Endemic North African Quercus afares Pomel originates from hybridisation between two genetically very distant oak species (Q. suber L. and Q. canariensis Willd.): evidence from nuclear and cytoplasmic markers.
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Hybridisation is a potent force in plant evolution, although there are few reported examples of stabilised species that have been created through homoploid hybridisation. We focus here on Quercus afares, an endemic North African species that combines morphological, physiological and ecological traits of both Q. suber and Q. canariensis, two phylogenetically distant species. These two species are sympatric with Q. afares over most of its distribution. We studied two Q. afares populations (one from Algeria and one from Tunisia), as well as several populations of both Q. suber and Q. canariensis sampled both within and outside areas where these species overlap with Q. afares. A genetic analysis was conducted using both nuclear (allozymes) and chloroplastic markers, which shows that Q. afares originates from a Q. suber x Q. canariensis hybridisation. At most loci, Q. afares predominantly possesses alleles from Q. suber, suggesting that the initial cross between Q. suber and Q. canariensis was followed by backcrossing with Q. suber. Other hypotheses that can account for this result, including genetic drift, gene silencing, gene conversion and selection, are discussed. A single Q. suber chlorotype was detected, and all Q. afares individuals displayed this chlorotype, indicating that Q. suber was the maternal parent. Q. afares is genetically, morphologically and ecologically differentiated from its parental species, and can therefore be considered as a stabilised hybrid species. (+info)
Aspects of climate change prediction relevant to crop productivity.
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Projected changes in surface climate are reviewed at a range of temporal scales, with an emphasis on tropical northern Africa--a region considered to be particularly vulnerable to climate change. Noting the key aspects of 'weather' affecting crop yield, we then consider relevant and projected change using output from a range of state of the art global climate models (GCMs), and for different future emission scenarios. The outputs from the models reveal significant inter-model variation in the change expected by the end of the twenty-first century for even the lowest IPCC emission scenario. We provide a set of recommendations on future model diagnostics, configurations and ease of use to close further the gap between GCMs and smaller-scale crop models. This has the potential to empower countries to make their own assessments of vulnerability to climate change induced periods of food scarcity. (+info)
The impact of smoking on adherence to treatment for latent tuberculosis infection.
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BACKGROUND: Studies have shown an association between smoking and tuberculosis (TB) infection, disease and TB-related mortality. We hypothesized that smokers with latent tuberculosis infection (LTBI) are less likely to comply with their LTBI treatment regimen, thus increasing their risk of developing active disease. We thus documented the impact of smoking on adherence to LTBI treatment. METHOD: Between 1998 and 2000, a convenience sample of patients undergoing treatment for LTBI completed a questionnaire on smoking status. Level of adherence to LTBI treatment was tested for associations with socio-demographic profile, and smoking status RESULTS: 320 patients were recruited, and 302 (94%) completed the questionnaire. Smoking prevalence was 21%. 72% of patients were adherent to LTBI treatment. Women (OR = 2.0; 95% CI: 1.2-3.3) and non-smokers (OR = 1.8; 95% CI: 1.0-3.3) were associated with adherence to LTBI treatment. Only gender was found as an independent predictor of adherence after adjusting for age and smoking status (OR = 1.9; 95% CI: 1.06-3.3). CONCLUSION: Males and smokers need to have extra supervision to ensure compliance with LTBI treatment. (+info)
Megaloblastic anemia in North Africa.
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We prospectively studied 478 patients with megaloblastic anemia living in Tunisia. Overall, 98% of patients had vitamin B12 deficiency. Pernicious anemia accounted for most of these cases, and median age at presentation was 45 years. Megaloblastic anemia occurred in 19 subjects under 15 years of age, and of these, nine had the Immerslund-Graesbeck syndrome. (+info)
LRRK2 G2019S in families with Parkinson disease who originated from Europe and the Middle East: evidence of two distinct founding events beginning two millennia ago.
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The leucine-rich repeat kinase 2 (LRRK2) G2019S mutation is the most common genetic determinant of Parkinson disease (PD) identified to date. It accounts for 1%-7% of PD in patients of European origin and 20%-40% in Ashkenazi Jews and North African Arabs with PD. Previous studies concluded that patients from these populations all shared a common Middle Eastern founder who lived in the 13th century. We tested this hypothesis by genotyping 25 microsatellite and single-nucleotide-polymorphism markers in 22 families with G2019S and observed two distinct haplotypes. Haplotype 1 was present in 19 families of Ashkenazi Jewish and European ancestry, whereas haplotype 2 occurred in three European American families. Using a maximum-likelihood method, we estimated that the families with haplotype 1 shared a common ancestor 2,250 (95% confidence interval 1,650-3,120) years ago, whereas those with haplotype 2 appeared to share a more recent founder. Our data suggest two separate founding events for G2019S in these populations, beginning at a time that coincides with the Jewish Diasporas. (+info)
The enigmatic epidemiology of nasopharyngeal carcinoma.
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Nasopharyngeal carcinoma (NPC) has a unique and complex etiology that is not completely understood. Although NPC is rare in most populations, it is a leading form of cancer in a few well-defined populations, including natives of southern China, Southeast Asia, the Arctic, and the Middle East/North Africa. The distinctive racial/ethnic and geographic distribution of NPC worldwide suggests that both environmental factors and genetic traits contribute to its development. This review aims to summarize the current knowledge regarding the epidemiology of NPC and to propose new avenues of research that could help illuminate the causes and ultimately the prevention of this remarkable disease. Well-established risk factors for NPC include elevated antibody titers against the Epstein-Barr virus, consumption of salt-preserved fish, a family history of NPC, and certain human leukocyte antigen class I genotypes. Consumption of other preserved foods, tobacco smoking, and a history of chronic respiratory tract conditions may be associated with elevated NPC risk, whereas consumption of fresh fruits and vegetables and other human leukocyte antigen genotypes may be associated with decreased risk. Evidence for a causal role of various inhalants, herbal medicines, and occupational exposures is inconsistent. Other than dietary modification, no concrete preventive measures for NPC exist. Given the unresolved gaps in understanding of NPC, there is a clear need for large-scale, population-based molecular epidemiologic studies to elucidate how environmental, viral, and genetic factors interact in both the development and the prevention of this disease. (+info)