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1.
Selenium (Se) is a naturally occurring trace element that is essential for animal and human nutrition, but the range between dietary requirements and toxic levels is relatively narrow. In this review, we are interested in the beneficial effects of selenium and we report on a number of studies of the selenium status of different populations in Saudi Arabia. The Status reflects the geographical area inhabited by the populations. Apart from the few available studies reviewed here, no data on the human status of Se in Saudi Arabia has been obtained. A further objective of this paper is throw some the light on the direction of future studies.  相似文献   

2.
We measured selenium (Se) levels in the urine and blood plasma samples of 72 Saudi Arabian patients with dilated cardiomyopathy (DCM) and 70 control subjects of the same origin. To correct for differences in the hydration state of the subjects, the selenium concentration for each urine sample was normalized by dividing it by the concentration of creatinine (CREAT) in the same sample. The median (and range) of the values found for the concentration of Se in plasma, urine, and normalized concentration in urine for the control subjects was 1.306 (0.66–2.50) μM, 0.478 (0.05–2.00) μM, and 56.7 (10.6–426.5) μM Se/M CREAT, respectively, whereas, for the patients, it was 1.246 (0.53–2.45) μM, 0.39 (0.05–1.90) μM, and 75.1 (4.9–656.2) μM Se/M CREAT, respectively. Additionally, the patients were separated into three subgroups according to the severity of their disease state as judged by NYHA procedure, and were then compared to the control group. Only group 4 (the most severe state of the disease) had a significantly lower concentration of urinary Se than the control group. However, the difference became nonsignificant when normalized for CREAT levels. There was no significant difference in the plasma Se levels between the controls and any of the patient groups. As the plasma Se in the control group and in the DCM patients both fell on the low end of the “normal” range, with the patients being marginally lower than the controls, there is no firm evidence from this study to suggest that Se is related to the high incidence rate of DCM found in Saudi Arabia.  相似文献   

3.
BackgroundThe synthesis of thyroid hormone depends on a set of trace elements, most importantly selenium and iodine. The dietary supply with certain micronutrients is limited in many areas of the world, including central Europe and large parts of Asia and Africa. Moreover, both thyroid disease risk and therapy effects are modulated by trace element supply and status.ObjectiveAssessment of trace element status in thyroid patients in a European metropolis.Material and MethodsAdult patients visiting a medical praxis in Berlin, Germany, were enrolled into a cross-sectional analysis, and serum samples were obtained from thyroid patients (n = 323) with different conditions including goitre, hypothyroidism, malignancy or autoimmune thyroid disease. Trace elements (iodine, selenium, copper and zinc) were assessed by ICP-MS/MS or total reflection X-ray analysis, along with two protein biomarkers of selenium status (selenoprotein P, glutathione peroxidase), and compared to the clinical phenotype.ResultsThe patients displayed relatively low serum zinc and selenium concentrations as compared to a set (n = 200) of healthy subjects (zinc; 1025+/-233 vs. 1068+/−230 μg/L, p < 0.01, selenium; 76.9+/18.8 vs. 85.1+/−17.4 μg/L, p < 0.0001). A high fraction of patients (37.5%) was classified as selenium-deficient (serum selenium concentrations <70 μg/L), in particular the patients with thyroid malignancy (59%). Serum copper was not different between the groups, and total serum iodine concentrations were unrelated to thyroid disease. Explorative statistical analyses yielded no significant interactions between the trace elements and disease parameters, except for free thyroxine inversely correlating to the copper/selenium ratio.ConclusionsIn adult thyroid patients, there is no relation of circulating copper, iodine, selenium or zinc concentrations to thyroid hormone. However, a large fraction of German thyroid patients displays a considerable selenium deficit, known to constitute a disease risk potentially impairing convalescence and aggravating autoimmune disease processes. It appears advisable to testing thyroid patients for selenium deficiency, and once diagnosed, an increased supply via dietary counselling or active supplementation should be considered.  相似文献   

4.
Work aimed at assessing status and introducing water conservation regimes for coffee production in southern Saudi Arabian highlands. Data on farm locations, altitudes, areas, practices, irrigation, tree density, and annual coffee production were analyzed. Field experiment using chlorophyll fluorescence and different irrigation regimes was conducted to examine effects of reducing irrigation frequency on photosynthesis. Results indicated that Coffea arabica L. is commonly grown at altitudes of 1300–1400 m. Plants grown at 4–6 Trees m?2 using 100 kg ha?1 mineral fertilizer produce an average of 3 t ha?1. High frequency 2-day-intervals irrigation regime practiced by farmers during the dry season presents ecological challenge to limited local artesian water resources. Changes in chlorophyll fluorescence under 14-day-intervals irrigation regime initiated water stress that markedly inhibited Photosystem II efficiency and quantum yield and increased non-photochemical energy dissipation. Applying a 7-day-intervals irrigation regime induced less inhibitory effects on Photosystem II. Results also indicated that shifting from 2-day-intervals irrigation regime to 7-day-intervals regime improves coffee agroecology and directs coffee production towards sustainability.  相似文献   

5.
Belk  Denton  Peters  Wm. David 《Hydrobiologia》1997,359(1-3):203-206
Anostracans were found living in ephemeral pools in the dark sections of three caves on the As Summan Plateau in Saudi Arabia. Branchipus schaefferi Fischer, 1834 occurred alone in one while it cohabited with Streptocephalus torvicornisbucheti Daday, 1910 in a second cave; fairy shrimps were observed but not collected from the third. None of the specimens demonstrated any of the types of morphological changes typically associated with cave adapted species. This is likely due to continuing colonization of the pools during flooding events. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

6.
Middle phalangeal hair was found to be present in 71% if Saudi Arabian males. For those exhibiting this trait, the frequency of combinations of digits with hair was similar to the frequency in other populations.  相似文献   

7.
《Mammalian Biology》2014,79(6):409-413
This work represents the most extensive genetic study of the grey wolf (Canis lupus Linnaeus, 1758) in Arabia and the first considering genetic data from multiple locations within Saudi Arabia. Previous suggestion of the occurrence of two subspecies of wolves in Arabia is not supported by this study. The genetic evidence suggests that the wolves of Saudi Arabia are genetically variable and more closely related to the Eurasian wolf Canis lupus group (dog included) than to the Indian wolf C. l. pallipes. The genetic diversity observed for C. lupus in Saudi Arabia indicates that the subspecific status C. l. arabs should be retained for the Arabian wolf. What remains unclear is the degree to which genetic introgression from domestic dogs has influenced the composition and integrity of C. lupus in Saudi Arabia.  相似文献   

8.
Although Human Adenoviruses outbreaks are rare, there still could be a potential chance for those viruses to mutate and spread quickly in human populations with severe public health and socioeconomic consequences. Outbreaks often spread fairly quickly with considerable morbidity/mortality. Saudi Arabia’s geopolitical and religious significance bring with it, millions of pilgrims, and tourists yearly. This presents a significant potential for HAdVs epidemics. This review shows that even with the mushrooming serotypes and genotypes, the scholarly knowledge on the nature, structure, transmission, and management of HAdVs is already well-established. Significant research is ongoing on pharmacological interventions, which, presently remain speculative and lacking in effectiveness. This review similarly uncovers a shortage of literature, both recent and dated, on epidemic keratoconjunctivitis in either Saudi Arabia or the Middle East.  相似文献   

9.
10.
In the Kingdom of Saudi Arabia (KSA), hospital and population based statistics have shown that breast cancer has the highest crude frequency rate among Saudi women. The scarcity of reports about the disease in the KSA has been the impetus to this analysis about breast cancer in the eastem province of KSA. Data on female patients with invasive breast carcinoma seen at King Fahd Hospital of the University in the eastern province of KSA, were retrospectively reviewed. The analysis intended to examine the pattern of the disease and the outcome for patients. Between 1985 and 1995, 292 patients were identified. Their median age±SD (standard deviation) was 42±10.5 years. Most patients were younger than 50 years (78%) and were predominantly premenopausals (79%). Only 25 (9%) of patients had stage I cancer, whilst 130 (44%), 90 (30%), and 47 (16%) had stage II, III, and IV, respectively. Among patients with known axillary nodal status (242 patients), only 37% were node-negative whilst 32% and 31% had 1–3, and ≥4 positive nodes, respectively. Adjuvant chemotherapy and tamoxifen were commonly offered; nonetheless, other adjuvant modalities were rarely utilised. The median follow-up ±SD of all patients was 62.3±8.9 months: 152 patients (52%) were alive with no evidence of disease, 25 (9%) were alive with evidence of disease, and 115 (39%) were dead from breast cancer or its related complications. The median survival of the entire group was not obtained, but the 10-year projected survival was 55%. For stage I and II patients, 118 (76%) were alive with a projected 10-year actuarial survival of 64%. On the other hand, only 51 (57%) of patients with stage III disease were alive with a median survival of 41.5 months (95% Confidence interval (CI), 18.9 to 51.3). Patients with stage IV disease demonstrated a poor outcome with a median survival of 23.5 (95%, CI 12.2 to 31.4). Multivariate analyses were performed to explore the influence of independent variables on overall survival (OS) for patients with non-metastatic disease. Besides the expected adverse effect of disease progression, the favourable influence of adjuvant chemotherapy and tamoxifen prevailed. The amount of benefit gained from tamoxifen, however, was small. Similar analyses were undertaken to determine the influence of independent variables on progression-free survival (PFS). These analyses ascertained the adverse effects of advanced stage and the favourable impact of adjuvant chemotherapy. Breast cancer in the KSA has features that are distinctive from those of industrialised countries. Survival data, however, were comparable. The favourable influence of adjuvant chemotherapy was evident on both OS and PFS. Adjuvant tamoxifen, however, had little effect. Due to its infrequent use, the role of other adjuvant modalities could not be asserted.  相似文献   

11.
BackgroundStatins have multiple antiatherosclerotic effects, but can reduce blood plasma concentrations of minerals, including zinc. As zinc possesses antiinflammatory and antioxidant effects, low zinc status can promote injuries or inadequate tissue repair in endothelial cells. Metallothionein (MT) expression might modulate responses induced by statins in patients with atherosclerosis. However, research regarding mineral status and the use of statins is scarce. This study evaluated the effects of zinc supplementation on zinc status and expression of the zinc-dependent MT1F and MT2A genes in patients with atherosclerosis treated with rosuvastatin.MethodsA double-blind, randomized clinical trial was performed with 54 participants treated with 10 mg rosuvastatin for 4 months with or without zinc supplementation (30 mg/day). Diet, lipid profile, high-sensitivity reactive protein C (hs-CRP), plasma and erythrocyte zinc concentrations, erythrocyte superoxide dismutase (SOD) activity, and MT1F and MT2A genes expression were analyzed before and after intervention.ResultsRosuvastatin therapy was effective in reducing low- and non-high-density lipoprotein, total cholesterol, triglycerides, and hs-CRP levels, independent of zinc supplementation. Additionally, zinc treatment had no effect on SOD enzyme activity (P = 0.201), plasma (P > 0.671) and erythrocyte (P > 0.123) zinc concentrations, or the pattern of MT1F and MT2A genes expression (P = 0.088 and P = 0.229, respectively).ConclusionsThe effectiveness of rosuvastatin treatment is independent of the effects of zinc supplementation. Moreover, rosuvastatin treatment did not have a significant impact on zinc status or MT1F and MT2A genes expression in patients with atherosclerosis.  相似文献   

12.
Fungi inhabiting household environments in the West, East and Central localities of Riyadh city were screened. The screened area included bedrooms, drawing rooms, living rooms, kitchens and bathrooms. The common genera of fungi isolated wereAlternaria, Aspergillus, Cercospora, Chaetomium, Cladosporium, Curvularia, Drechslera, Embellisia, Fusarium, Mucor, Penicillium, Rhizopus, Scytalidium, Trichoderma, Torula andUlocladium. Two uncommon generaNodulosporium andOidiodendron for Saudi Arabian mycoflora were also isolated. In all the localities, the highest number of fungal colonies per plate or per gram were found in the living rooms, followed by bedrooms. The number of colonies per plate or per gram was in general higher in densely populated than in less populated areas.  相似文献   

13.
A total of 292 randomly selected subjects belonging to two indigenous Arab tribes (Harbi and Ghamid) and two immigrant tribes (Mograbi and Mowallad), residents in Western Saudi Arabia, have been tested for genetic variants of six blood groups, four serum proteins, and five red cell enzyme systems. The distribution of the polymorphic systems was different between indigenous and immigrant tribes, and the present Arab population shows a considerable degree of admixture from the surrounding countries, in particular Africa.  相似文献   

14.
Well-preserved palynomorph assemblages are recovered from the Devonian Jauf and Jubah formations in five shallow boreholes in the northern part of Saudi Arabia. These fully cored boreholes overlap stratigraphically to form a 1640 ft composite sequence. Miospores dominate the palynological assemblages of most samples. The assemblages are mainly composed of trilete spores but also contain cryptospores and monolete spores. One new genus, sixteen new species and two new varieties of miospores are described from the studied assemblages: Artemopyrainconspicua nov. sp., Artemopyrarecticosta nov. sp., Camarozonotriletesfilatoffii nov. sp., Camarozonotriletesrugulosus nov. sp., Cymbohilatesbaqaensis nov. sp., Cymbohilatescomptulus nov. sp., Cymbohilatesheteroverrucosus nov. sp., Cymbosporitesasymmetricus nov. sp., Dibolisporitespilatus nov. sp., Dictyotriletesbiornatus nov. sp., Gneudnasporadivellomedia (Chibrikova) Balme, 1988 var. divellomedia, Gneudnasporadivellomedia (Chibrikova) Balme, 1988 var. minor nov. var., Latosporitesovalis nov. sp., Scylasporacostulosa nov. sp., Squamisporaarabica nov. gen. and sp., Stellatisporamulticostata nov. sp., Zonotriletesarmillatus nov. sp. and Zonotriletessimplicissimus nov. sp. Their stratigraphic distribution is compared to the well-established Devonian West European zonation of Streel et al. (1987) (Streel, M., Higgs, K.T., Loboziak, S., Riegel, W., Steemans, P., 1987. Spore stratigraphy and correlation with faunas and floras in the type marine Devonian of the Ardenne-Rhenish region. Review of Palaeobotany and Palynology 50, 211-219). A late Pragian-Givetian age is suggested for this sequence. No characteristic Eifelian taxa are recorded, but this could be explained by a gap in palyniferous samples.  相似文献   

15.
Seed-borne fungi from seeds of barley, canary, maize, oats, rice, rapeseed, red millet, sunflower, white millet and yellow millet were investigated. These seeds are available in the market as bird feed, supplied by companies in various countries as healthy and nutritious food for domestic birds. A total of 81 fungal species were isolated. The genusAspergillus was predominant with 23 species, followed byPenicillium with 18,Ulocladium with 7,Alternaria with 6 andChaetomium, Curvularia andDrechslera with 5 species each. Other genera isolated wereAureobasidium, Cladosporium, Fusarium, Mucor, Rhizopus andSyncephalastrum.  相似文献   

16.
Conservation in the Kingdom of Saudi Arabia is relatively young, yet have made considerable gains in conservation through strategic proclamation and reintroductions. Changes in land use, illegal hunting and competition with domestic stock has decimated the native ungulates, meaning that the survival of the native ungulate species is now completely dependent on protected area network. The challenge is to sustain this network to make meaningful conservation impact into the future. We review the status of ungulate conservation in Saudi Arabia and highlight that the conservation strategy is well developed. The major challenge faced in conservation in Saudi Arabia now is to implement what has been sanctioned.  相似文献   

17.
Two new megaspore species, Biharisporites jubahensis and Verrucisporites yabrinensis, are described from the Middle Devonian Jubah Formation of south central Saudi Arabia. Miospore-based biostratigraphy indicates that the age of the megaspore-bearing interval is no older than the early Givetian Geminospora lemurata Interval Zone, and not younger than Givetian. The presence of similar species in both Arctic Canada and Saudi Arabia suggests that the megaspore-producing plants achieved wide distribution in the Middle Devonian.  相似文献   

18.
A sum of 218 composite rhizosphere soil samples were collected from around the feeder roots of mango, Mangifera indica growing in Jazan region, the tropical south west corner of Saudi Arabia. Samples were rendered for nematodes extraction using the centrifugal floatation method, and the stylet-bearing nematodes were morphologically identified according to the standardized taxonomical keys. A list of 14 stylet-bearing nematode genera and/or species were found to be associating the roots of mango in this study. Species identification of the most important parasitic nematodes, in this list, was carried-out, based on morphometrics and morphological features. Identification of these species was then molecularly confirmed using the D3 expansion region of 28S ribosomal RNA (rRNA) gene. These nematodes included; Tylenchorhynchus mediterraneus, Hoplolaimus seinhorsti, Hemicriconemoides strictathecatus, Longidorus latocephalus and Xiphinema elongatum. Some new local nematode-host records in Saudi Arabia were recorded including; Aphelenchus sp., H. strictathecatus, L. latocephalus, and T. mediterraneus. Some new world nematode-host records were also reported including; L. latocephalus and T. mediterraneus.  相似文献   

19.
This study was conducted to investigate phytophagous and predatory mites associated with vegetable plants in Riyadh, Saudi Arabia. Eight phytophagous and 10 predacious mites were collected from 14 species of vegetable crops covering five major production localities. Out of these 18 mite species, 13 species are new to the mite fauna of Saudi Arabia. In addition, the two species, Tenuipalpus punicae and Agistemus exsertus, are reported for the first time on vegetable crops in Saudi Arabia. For each mite species found, notes on host plant association and occurrence period are given. An illustrated key for the identification of the 18 mite species reported in this study is provided and this can be used to improve the IPM programs by applying the local natural predatory mites in controlling mite pests in Saudi Arabia.  相似文献   

20.
One hundred and forty mammals of fifteen different species belonging to nine families, collected during one-year survey period in Turaif province of Saudi Arabia, are reported. Collections were made during studying the diversity of land vertebrate fauna of Turaif area at the northern province of Saudi Arabia. Cricetidae (n?=?64) was the most common family. Jaculus jaculus vocator (n?=?34) was recorded the highest number of events for any mammal in the surveyed area followed by Gerbillus nanus (n?=?23). Two species of mammals namely G. nanus (n?=?23) and Felis margarita (n?=?3) were reported for the first time in the study area. The geographical distribution of the collected species within this province was mapped.  相似文献   

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