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1.
Electrophoresis in starch gel has been used to study the polymorphism of hordeins encoded by loci Hrd A, Hrd B, and Hrd F in 140 local barley populations from the Near East, including 60, 34, 33, 8, and 5 populations from Syria, Jordan, Iraq, Palestine, and Israel, respectively. Fifty-seven Hrd A, 87 Hrd B, and 5 Hrd F alleles have been found. The alleles of these loci considerably differ in frequencies and distribution in populations from different Near Eastern countries. Cluster analysis of the matrix of the frequencies of hordein locus alleles in barley populations from the Near East, North Africa, Ethiopia, and South Arabia has yielded two clusters. The first cluster includes barley populations from Israel, Palestine, Morocco, Tunisia, Algeria, and Egypt; the second cluster, populations from Iraq, Syria, Jordan, Yemen, and Ethiopia.  相似文献   

2.
Electrophoresis in starch gel has been used to study the polymorphism of hordeins encoded by loci Hrd A, Hrd B, and Hrd F in 140 local barley populations from the Near East, including 60, 34, 33, 8, and 5 populations from Syria, Jordan, Iraq, Palestine, and Israel, respectively. Fifty-seven Hrd A, 87 Hrd B, and 5 Hrd F alleles have been found. The alleles of these loci considerably differ in frequencies and distribution in populations from different Near Eastern countries. Cluster analysis of the matrix of the frequencies of alleles of hordei-coding locus alleles in barley populations from the Near East, North Africa, Ethiopia, and South Arabia has yielded two clusters. The first cluster includes barley populations from Israel, Palestine, Morocco, Tunisia, Algeria, and Egypt; the second cluster, populations from Iraq, Syria, Jordan, Yemen, and Ethiopia.  相似文献   

3.
The neglected tropical diseases (NTDs) are highly endemic but patchily distributed among the 20 countries and almost 400 million people of the Middle East and North Africa (MENA) region, and disproportionately affect an estimated 65 million people living on less than US$2 per day. Egypt has the largest number of people living in poverty of any MENA nation, while Yemen has the highest prevalence of people living in poverty. These two nations stand out for having suffered the highest rates of many NTDs, including the soil-transmitted nematode infections, filarial infections, schistosomiasis, fascioliasis, leprosy, and trachoma, although they should be recognized for recent measures aimed at NTD control. Leishmaniasis, especially cutaneous leishmaniasis, is endemic in Syria, Iran, Iraq, Libya, Morocco, and elsewhere in the region. Both zoonotic (Leishmania major) and anthroponotic (Leishmania tropica) forms are endemic in MENA in rural arid regions and urban regions, respectively. Other endemic zoonotic NTDs include cystic echinococcosis, fascioliasis, and brucellosis. Dengue is endemic in Saudi Arabia, where Rift Valley fever and Alkhurma hemorrhagic fever have also emerged. Great strides have been made towards elimination of several endemic NTDs, including lymphatic filariasis in Egypt and Yemen; schistosomiasis in Iran, Morocco, and Oman; and trachoma in Morocco, Algeria, Iran, Libya, Oman, Saudi Arabia, Tunisia, and the United Arab Emirates. A particularly noteworthy achievement is the long battle waged against schistosomiasis in Egypt, where prevalence has been brought down by regular praziquantel treatment. Conflict and human and animal migrations are key social determinants in preventing the control or elimination of NTDs in the MENA, while local political will, strengthened international and intersectoral cooperative efforts for surveillance, mass drug administration, and vaccination are essential for elimination.  相似文献   

4.
Hyalomma aegyptium ticks were collected from tortoises, Testudo graeca, at localities in northern Africa, the Balkans, and the Near and Middle East. The intensity of infestation ranged from 1-37 ticks per tortoise. The sex ratio of feeding ticks was male-biased in all tested populations. Larger tortoises carried more ticks than did the smaller tortoises. The juveniles were either not infested, or carried only a poor tick load. Hyalomma aegyptium was absent in the western Souss Valley and Ourika Valley in Morocco, the Cyrenaica Peninsula in Libya, Jordan, and the Antilebanon Mountains in Syria. Hemolivia mauritanica, a heteroxenous apicomplexan cycling between T. graeca and H. aegyptium, was confirmed in Algeria, Romania, Turkey, Syria, Lebanon, and Iran. Its prevalence ranged from 84% in Romania (n = 45), 82% in eastern Turkey (n = 28), and 82% in the area of northwestern Syria with adjacent Turkish borderland (n = 90), to 38% in Lebanon (n = 8) and in only 1 of 16 sampled tortoises in Algeria. The intensity of parasitemia in the studied areas ranged from 0.01% up to 28.17%. The percentage of Hemolivia-infected erythrocytes was significantly higher in adults. All tortoises from Hyalomma-free areas were Hemolivia-negative. Remarkably, all 29 T. graeca from Jabal Duruz (southwestern Syria) and 36 T. graeca from the area north of Middle Atlas (Morocco) were Hemolivia-negative, despite the fact that ticks parasitized all adult tortoises in these localities. Identical host preferences of H. aegyptium and H. mauritanica suggest the occurrence of co-evolution within the Testudo-Hyalomma-Hemolivia host-parasite complex.  相似文献   

5.
With the increasing life expectancy, osteoporosis is becoming a major worldwide health problem. The magnitude of the disease may become larger in developing countries, more particularly in the Middle East region where the prevalence of low bone mass is higher than in western countries. Although several local organizations and countries have developed guidelines for osteoporosis, no previous regional guidelines have been developed encompassing all Middle-Eastern and North African countries. The present document reviews all the regional published data on bone mineral density, risk factors, fracture prevalence and vitamin D status. It also gives simple recommendations applicable to all these countries. This document was endorsed by leading members of all the different regional countries including, Iran, Egypt, Tunisia, Jordan, Palestine, Syria, Iraq, Libya, Oman, Kuwait, Saudi Arabia and Bahrain.  相似文献   

6.
The cluster population structure of barley landraces with known sampling localities in nine countries of Southwest Asia, the Middle East, North and Northeast Africa, and South Arabia was examined using the allele-frequency data for three hordein-coding loci. A total of 92 populations from Turkey, 56 populations from Syria, 34 from Jordan, 23 populations from Iraq, 6 from Morocco, 16 from Algeria, 34 populations from Egypt, 100 from Ethiopia, and 71 populations from Yemen with known sampling localities were included in the analysis. It was demonstrated that the cluster population structure in different countries was different and varied from a single cluster in Morocco to five clusters in Ethiopia. Furthermore, populations with sampling sites located at a considerable distance from one another were grouped into one cluster. It is suggested that the existence of several population clusters within a single country can be evidence of repeated population introduction, while the grouping of the populations with sampling sites considerably distant from one another into one cluster can indicate the distribution of once introduced populations of cultivated barley within countries through local farmer migration.  相似文献   

7.

Objective

To characterize hepatitis C virus (HCV) epidemiology in countries of the Fertile Crescent region of the Middle East and North Africa (MENA), namely Iraq, Jordan, Lebanon, Palestine, and Syria.

Methods

We systematically reviewed and synthesized available records of HCV incidence and prevalence following PRISMA guidelines. Meta-analyses were implemented using a DerSimonian-Laird random effects model with inverse weighting to estimate the country-specific HCV prevalence among the various at risk population groups.

Results

We identified eight HCV incidence and 240 HCV prevalence measures in the Fertile Crescent. HCV sero-conversion risk among hemodialysis patients was 9.2% in Jordan and 40.3% in Iraq, and ranged between 0% and 3.5% among other populations in Iraq over different follow-up times. Our meta-analyses estimated HCV prevalence among the general population at 0.2% in Iraq (range: 0–7.2%; 95% CI: 0.1–0.3%), 0.3% in Jordan (range: 0–2.0%; 95% CI: 0.1–0.5%), 0.2% in Lebanon (range: 0–3.4%; 95% CI: 0.1–0.3%), 0.2% in Palestine (range: 0–9.0%; 95% CI: 0.2–0.3%), and 0.4% in Syria (range: 0.3–0.9%; 95% CI: 0.4–0.5%). Among populations at high risk, HCV prevalence was estimated at 19.5% in Iraq (range: 0–67.3%; 95% CI: 14.9–24.5%), 37.0% in Jordan (range: 21–59.5%; 95% CI: 29.3–45.0%), 14.5% in Lebanon (range: 0–52.8%; 95% CI: 5.6–26.5%), and 47.4% in Syria (range: 21.0–75.0%; 95% CI: 32.5–62.5%). Genotypes 4 and 1 appear to be the dominant circulating strains.

Conclusions

HCV prevalence in the population at large appears to be below 1%, lower than that in other MENA sub-regions, and tending towards the lower end of the global range. However, there is evidence for ongoing HCV transmission within medical facilities and among people who inject drugs (PWID). Migration dynamics appear to have played a role in determining the circulating genotypes. HCV prevention efforts should be targeted, and focus on infection control in clinical settings and harm reduction among PWID.  相似文献   

8.
This special issue explores the prospects for what Jacob Mundy calls ‘transformative minority politics’ in the Middle East and North Africa (MENA) region – that is, a form of minority politics that strengthens democratic reform in the region, and that helps deepen a culture of human rights and democratic citizenship. The cases examined in the special issue include the Amazigh in North Africa, the Copts in Egypt, the Kurds in Iraq, the Palestinians in Israel, the ‘minoritarian’ regimes in Syria and Bahrain, and the various ethnic minorities in Iran. In this introduction, we try to situate this debate in a larger historical and international context, identifying some of the factors that might help support a new transformative minority politics in the region, while also emphasizing the factors that have inhibited it in the past, and why they remain powerful.  相似文献   

9.
The article discusses some basic aspects of the integrated production and protection of horticultural crops, basically vegetables (e.g. tomatoes, cucumbers, peppers, eggplants, beans, etc.) and fruit trees (bananas), as well as flowers grown under cover in the Mediterranean region, namely Morocco, Syria, Lebanon, Egypt, Jordan, Tunisia, Cyprus, and Turkey.  相似文献   

10.
Aim  Middle East brown bears ( Ursus arctos syriacus Hemprich and Ehrenberg, 1828) are presently on the edge of extinction. However, little is known of their genetic diversity. This study investigates that question as well as that of Middle East brown bear relationships to surrounding populations of the species.
Location  Middle East region of south-western Asia.
Methods  We performed DNA analyses on 27 brown bear individuals. Twenty ancient bone samples (Late Pleistocene to 20th century) from natural populations and seven present-day samples obtained from captive individuals were analysed.
Results  Phylogenetic analyses of the mitochondrial sequences obtained from seven ancient specimens identify three distinct maternal clades, all unrelated to one recently described from North Africa. Brown bears from Iran exhibit striking diversity (three individuals, three haplotypes) and form a unique clade that cannot be linked to any extant one. Individuals from Syria belong to the Holarctic clade now observed in Eastern Europe, Turkey, Japan and North America. Specimens from Lebanon surprisingly appear as tightly linked to the clade of brown bears now in Western Europe. Moreover, we show that U. a. syriacus in captivity still harbour haplotypes closely linked to those found in ancient individuals.
Main conclusion  This study brings important new information on the genetic diversity of brown bear populations at the crossroads of Europe, Asia and Africa. It reveals a high level of diversity in Middle East brown bears and extends the historical distribution of the Western European clade to the East. Our analyses also suggest the value of a specific breeding programme for captive populations.  相似文献   

11.
The sweet potato whitefly, Bemisia tabaci (Gennadius), is a cryptic species complex composed of at least 24 different morphologically indistinguishable species. The considerable differences in the pest status across the complex, and the ability of some to develop resistance to, insecticides make awareness of their identity critical in terms of developing effective control measures. Previously, phylogenetic reconstructions have been used to identify different B. tabaci, but this approach is no longer necessary because of the existence of mitochondrial cytochrome oxidase one consensus sequences for each of the known species. We therefore use these consensus sequences to determine the identities of the members of the complex in Syria and Egypt and then used genetic networks to reveal the pattern of their genetic relatedness to other haplotypes in the species to which they were assigned. The results showed the presence of three species in Syria, AsiaII 1, Middle East–Asia Minor 1 (this equates to the global invader known commonly as the B biotype) and Mediterranean (this equates to the global invader known commonly as the Q biotype). Egypt was shown to have two cryptic species, Middle East–Asia Minor 1 and Mediterranean. In Syria, Middle East–Asia Minor 1 was found around Damascus only (south‐west Syria), while Mediterranean was found throughout Aleppo (northern Syria) and Hama (north central Syria). AsiaII 1 was found around Hims (south central Syria) and Damascus (south‐western Syria). In Egypt, Mediterranean was found in Cairo and Ismailia (central Upper Egypt), while Middle East–Asia Minor 1 was found in the remaining all parts of Upper Egypt, Suez, North Sinai, Port Said, Dakahila, Behera and Alexandria which cover the main agricultural zone of Egypt. Genetic relatedness of Syrian and Egyptian populations with each other and with rest of world is also discussed.  相似文献   

12.
Summary The Avena sterilis collection in the National Small Grains Collection (NSGC) is an invaluable source of genetic variation to be exploited by oat breeding programs. Prior knowledge of the structure and distribution of genetic variation within the A. sterilis collection would be useful to efficiently screen the collection for valuable traits. To determine genetic structure within a subset of the collection, restriction fragment length polymorphisms were analyzed in a stratified sample of 173 accessions originating in eight countries of Africa and Southwest Asia. Of the 48 probes used for this study 43 detected polymorphism among accessions. The average number of RFLP patterns per probe ranged from 2.9 among Ethiopian accessions to 3.7 among those from Iran. Genetic variation, as measured by genetic distances and polymorphic indexes, was highest in Iran and lowest in Ethiopia. The probability of drawing a genotype from Iran or Iraq that is not present in the more western regions was high, indicating large genetic divergence of the Iran-Iraq accessions from the other regional collections surveyed. Cluster analysis of genetic distances and probabilities of unique genotypes clearly differentiated the eastern region (Iran and Iraq) from the western region (Algeria, Ethiopia, Israel, Lebanon, Morocco, and Syria). The western region could be further subdivided into two clusters, an African cluster (Algeria, Ethiopia, and Morocco) and a southwestern Asia cluster (Israel, Lebanon, and Syria). Genetic distances were generally related to but not proportional to geographical distances.  相似文献   

13.
On the basis of the material collected in Morocco, Algeria, Tunisia, Lebanon, Syria and Turkey, and published data, mainly on Israel and Egypt, we try to establish a synthesis of the geographical distribution of the poorly known fauna of the South and Eastern Mediterranean basin. A first analysis shows that the fauna of this region is characterized by a high number of species with a widespread distribution (cosmopolite, holarctic, palaearctic ...) and therefore, with great affinities with the European fauna. Nevertheless, three distinct communities can be distinguished:

  • - The south western basin (North Africa; Morocco, Algeria, Tunisia), where the community is very poor, and which shows great affinities with south European, but none with the Ethiopian region;
  • - The south eastern basin (Egypt), with some species of African origin;
  • - The eastern basin (Near East, mainly Lebanon and Israel) with a very diversified community, partly due to its geographical situation, and partly due to a more intensive collecting pressure. This community includes a group of species with more eastern affinities (East Siberian ...), but none typically Ethiopian or exclusively Sino-Indian.
  •   相似文献   

    14.
    Phlebotomus papatasi (Scopoli) (Diptera: Psychodidae) is the main vector of Leishmania major Yakimoff & Schokhor; which is the cause of self-limiting cutaneous leishmaniasis in the Old World. This sandfly is found in houses, animal shelters, caves and rodent burrows. It has a large geographical range, which includes the Middle East and the Mediterranean regions. A population analysis of colony and field specimens of P. papatasi was conducted on 25 populations originating from 10 countries. The distribution of haplotypes of the maternally inherited mitochondrial cytochrome b gene were analysed to assess the population differentiation of P. papatasi. Alignment of a 442-basepair region at the 3' end of the gene identified 21 haplotypes and 33 segregating sites from 131 sandflies. The pattern of sequence variations did not support the existence of a species complex. The median-joining network method was used to describe both the origin of the haplotypes and the population structure; haplotypes tended to cluster by geographical location, suggesting some level of genetic differentiation between populations. Our findings indicate the presence of significant population differentiation for populations derived from Syria, Turkey, Palestine, Israel, Jordan and Egypt. Knowledge of population differentiation among P. papatasi populations is important for understanding patterns of dispersal in this species and for planning appropriate control measures.  相似文献   

    15.
    The Bridled Skink, Trachylepis vittata, is widespread in the Middle East and eastern coastal Mediterranean areas and inhabits foothills throughout the arid regions of the Middle East. With the help of more than 146 distribution records from Iran, Turkey, Syria, Israel, Jordan, Cyprus, Egypt, Lebanon and Libya, we analysed the influence of climate on the distribution pattern. According to the Maximum Entropy model, the most influential factors that determined T. vittata distribution are: precipitation of coldest quarter, Normalised Difference Vegetation Index (NDVI) and precipitation in the warmest quarter. The model suggests that the western slopes of the Zagros Mountains in Iran and slopes in the southern regions of Anatolia around the Mediterranean Sea are suitable for this species. The species is associated with areas with intermediate NDVI (150-180) (a measure of primary productivity), high winter precipitation (>300?mm) and dry summer (<50mm). The association with rainy winter limits the presence of the species in lowlands. The Zagros Mountains may act as a biogeographic barrier that limits the species dispersal eastward, because of their scarce precipitation.  相似文献   

    16.
    Migrations into Africa from the Levant have greatly determined the mitochondrial genetic landscape of North Africa. After analyzing samples from North Morocco to Spain, we show that three fourths of the Moroccan individuals belong to Western Eurasian haplogroups and the frequencies of these are much more similar to those of the Iberian Peninsula than to those of the Middle East. This is particularly true for the mitochondrial haplogroups H1, H3 and V, which experienced a late-glacial expansion from this region, that repopulated much of Central and Northern Europe. Iberian Peninsula was also a source for prehistoric migrations to North Africa.  相似文献   

    17.
    The ostracod fauna collected from the Cherahil formation that crops out at the Jebel Serj section (central Tunisia) contains 24 species belonging to 12 genera. These ostracods are associated with 9 genera of benthic Foraminifera (including 4 Nummulites species) and 7 genera of planktonic Foraminifera. The biostratigraphic study of ostracod assemblages results to the recognition of 6 biozones which are correlated with Lutetian-Priabonian. The Shannon Weaver, Margalef and equitability indices point to internal platform netritic conditions, with minor fluctuations in depth and oxygenation. The palaeobiogeographic distribution of ostracod species found in the study area of Central of Tunisia establishes a good connexion with the basins developed in Northern Africa (Tunisia, Algeria, Libya and Mauritania) and the Middle East (Egypt and Jordan).  相似文献   

    18.
    Two foot-and-mouth disease virus (FMDV) genome sequences have been determined for isolates collected from recent field outbreaks in North Africa (Egypt) and the Middle East (Palestinian Autonomous Territories). These data represent the first examples of complete genomic sequences for the FMDV SAT 2 topotype VII, which is thought to be endemic in countries immediately to the south of the Sahara desert. Further studies are now urgently required to provide insights into the epidemiological links between these outbreaks and to define the pathogenicity of this emerging lineage.  相似文献   

    19.
    The frequency distribution of Y-chromosome haplotypes at DNA polymorphism p49/TaqI was studied in a sample of 505 North Africans from Mauritania, Morocco, Algeria, Tunisia, Libya, and Egypt. A particularly high frequency (55.0%) of Y-haplotype 5 (A2, C0, D0, F1, I1) was observed in these populations, with a relative predominance in those of Berber origin. Examination of the relative frequencies of other haplotypes in these populations, mainly haplotype 4 (the "African" haplotype), haplotype 15 (the "European" haplotype), and haplotypes 7 and 8 (the "Near-East" haplotypes), permit useful comparisons with neighboring peoples living in sub-Saharan Africa, Europe, and the Near East.  相似文献   

    20.
    North African populations are distinct from sub-Saharan Africans based on cultural, linguistic, and phenotypic attributes; however, the time and the extent of genetic divergence between populations north and south of the Sahara remain poorly understood. Here, we interrogate the multilayered history of North Africa by characterizing the effect of hypothesized migrations from the Near East, Europe, and sub-Saharan Africa on current genetic diversity. We present dense, genome-wide SNP genotyping array data (730,000 sites) from seven North African populations, spanning from Egypt to Morocco, and one Spanish population. We identify a gradient of likely autochthonous Maghrebi ancestry that increases from east to west across northern Africa; this ancestry is likely derived from "back-to-Africa" gene flow more than 12,000 years ago (ya), prior to the Holocene. The indigenous North African ancestry is more frequent in populations with historical Berber ethnicity. In most North African populations we also see substantial shared ancestry with the Near East, and to a lesser extent sub-Saharan Africa and Europe. To estimate the time of migration from sub-Saharan populations into North Africa, we implement a maximum likelihood dating method based on the distribution of migrant tracts. In order to first identify migrant tracts, we assign local ancestry to haplotypes using a novel, principal component-based analysis of three ancestral populations. We estimate that a migration of western African origin into Morocco began about 40 generations ago (approximately 1,200 ya); a migration of individuals with Nilotic ancestry into Egypt occurred about 25 generations ago (approximately 750 ya). Our genomic data reveal an extraordinarily complex history of migrations, involving at least five ancestral populations, into North Africa.  相似文献   

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