Background: The variability in the distribution of the null phenotypes of GSTM1 and GSTT1, due to total or partial gene deletion resulting in the lack of the active enzyme, has been reported in different populations, ...Background: The variability in the distribution of the null phenotypes of GSTM1 and GSTT1, due to total or partial gene deletion resulting in the lack of the active enzyme, has been reported in different populations, especially in ethnically well-defined groups but not in Tabuk. This study investigated the variability in the distribution of the null phenotypes of GSTM1 and GSTT1 in the population of Tabuk (northwestern part of Saudi Arabia). Method: This study was conducted on 200 subjects of Tabuk—northwestern part of Saudi Arabia among which 100 were chronic smokers and 100 were nonsmokers. The subjects were reporting to hospital for routine checkup. All were without past history of any chronic disease and no significant abnormality. GST genotyping was done by multiplex PCR-based methods. The smoker and control groups were compared using a chi-square test with P GSTM1 deletion homozygosity of 14% and 1% was reported among non smokers and smokers, respectively whereas GSTT1 deletion homozygosity of 28% and 6% was reported among non smokers and smokers, respectively. Our results indicate that there are major differences in allelic distribution of GSTM1 and GSTT1 genes between the two groups investigated. Combined analysis of both genes revealed that 15% of smokers and non smokers harbor the deleted genotype of GSTM1 and 34% of smokers and non smokers harbor the deleted genotype of GSTT1 with significant differences. Conclusion: This study enables selecting subgroups among the general population who are more susceptible to DNA damage and will help genetic studies on the association of GST polymorphisms with disease risks and drug effects in Arab population. Studies with a larger sample size are needed to evaluate and confirm the validity of our results.展开更多
Background: Sickle cell disease and sickle cell trait are common erythrocyte disorders that are most often caused by a point mutation (rs334, designated HbS) in the hemoglobin beta gene (HBB);however of this fact, the...Background: Sickle cell disease and sickle cell trait are common erythrocyte disorders that are most often caused by a point mutation (rs334, designated HbS) in the hemoglobin beta gene (HBB);however of this fact, there is extreme variability in occurrence and clinical presentation of sickle cell disease which may be explained by some other genetic changes associated with the gene. In the present study we examined the association between HBB gene polymorphism rs33949930 T>C in the occurrence of sickle cell disease in Saudi Arabia population. Materials and Methods: A case control study of 100 sickle cell disease patients and 100 healthy controls from Tabuk, Saudi Arabia. HBB gene rs33949930 T>C polymorphism was analyzed using Allele specific polymerase chain reaction technique. Results: It was observed that the genotype percentages TT, TC and CC among the patients with sickle cell disease were 63.0%, 35.0% and 2.0% and healthy controls were 68.0%, 27.0% and 5.0% respectively. Allele frequency for T allele was observed to be fT = 0.20 and fT = 0.19, where as for C allele was fC = 0.80 and fC = 0.81 among cases and controls respectively (p = 0.29). Compared to the TT genotype, the odds ratio of 1.4 (95% CI 0.76 - 2.57), risk ratio of 1.2 (95% CI 0.86 - 1.65) and risk difference of 8.4 (-6.66 - 23.38) for heterozygous genotype of HBB rs33949930 T>C was observed in relation to sickle cell disease. In addition, some difference in the laboratory values was observed among sickle cell disease patients with the different variants of HBB gene rs33949930 T>C polymorphism, especially the carriers of heterozygous TC genotype;however, the difference doesn’t reach to statically significant number. Conclusion: Present study suggested that there was not any significant association between HBB gene rs33949930 T>C polymorphism and occurrence of sickle cell disease. However, the heterozygous TC genotype of the polymorphism showed some higher ratios among cases as compared to healthy control group.展开更多
Due to global climatic changes, flash floods are followed as a yearly disaster with high magnitude of influence. During the years 1981, 1988, 2010, 2012 and in January 2013, Tabuk city, northwest of Saudi Arabia suffe...Due to global climatic changes, flash floods are followed as a yearly disaster with high magnitude of influence. During the years 1981, 1988, 2010, 2012 and in January 2013, Tabuk city, northwest of Saudi Arabia suffered huge flash floods. These are major factors affecting on the swelling behavior of expansive Tabuk shale. The examined geotechnical properties of the surface and subsurface lithology of the sedimentary deposits distinguished Tabuk city into three zones. The expansive zone is spread in the middle and the non-expansive zones are distributed in the east and west of the city. The Watershed Modeling System (WMS) and Hydrologic Engineering Center (HEC-1) models were used to delineate and identify the drainage system and basin morphometry, where flash floods and accumulation of water might take place. Integration between geotechnical distribution maps of the expansion soil and surface hydrological data in terms of runoff maps was done. It has been identified the whereabouts the soils which have expansion characteristics and areas prone to flooding and surface runoff. They are helpful in defining the hazard zones map. Based on this map, it can be avoided constructions on the risk neighborhoods such as Al Qadsiyah, Al Maseif, Arrwdah, Al Nakhil and Al Rajhi. Also, it can suggest that the western side of Tabuk city is suitable for future urban extension. These results will help planners and citizens to create alternative development scenarios and determine their impact on the future urbanization patterns. Moreover, the direction of surface runoff flow or storm water discharge should be away from the expansion soil areas. Therefore, constructing dams on the outlet of the high-risk basins, south of Tabuk city is an important solution to control flash flood events, as well as increase groundwater recharge.展开更多
One main concern of power quality is harmonics because the distorted waveforms of current and voltage have a huge effect on electrical equipment. Due to the continuous increase of grid connected photovoltaic (PV) and ...One main concern of power quality is harmonics because the distorted waveforms of current and voltage have a huge effect on electrical equipment. Due to the continuous increase of grid connected photovoltaic (PV) and nonlinear loads, as a result of the fast development and growth of power electronics application, power quality becomes more important since it introduces harmonics to the power system. This paper presents a power quality study to the isolated northwest grid of Saudi Arabia in presence of PV system and battery storage. Moreover, the study includes nonlinear loads for more analysis regarding harmonics penetration and the design procedure for passive filters to eliminate the harmonics.展开更多
Background: Periodontitis is the predominant disease in the oral cavity and there are alterations in the periodontal tissues associated with the aging and gender of the patient. Objective: The present study was design...Background: Periodontitis is the predominant disease in the oral cavity and there are alterations in the periodontal tissues associated with the aging and gender of the patient. Objective: The present study was designed to assess the impact of age and gender of the patient on severity and types of periodontal diseases among patients from two regions in Saudi Arabia. Materials and Methods: The current study was done on 600 Saudi patients from Aseer and Tabuk regions in Saudi Arabia (50% males and 50% females) and divided into three equal groups (n = 200) according to the patients age: children and young patients (1 - 24 years old), adults patients (25 - 64 years old) and seniors patients (more than 65 years old). Plaque index (PLI), gingival index (GI), periodontal pocket depth (PPD) and clinical attachment loss (CAL) were recorded from all participants. The data were collected and analyzed with SPSS to determine the mean and standard deviation (±SD) and the values of significance (P ≤ 0.005). Results: The results of the present study revealed that 340 patients (56.7%) were affected with gingivitis dental biofilm induced and 260 patients were affected by periodontitis. Gingivitis dental biofilm-induced is especially detected in children and young patients (33.3%), adult patients (16.7%) and seniors patients (6.7%) whereas periodontitis cases were seen among the adult and seniors patients (16.7%) and (26.6%) respectively. Furthermore, the present study displayed the higher severity and prevalence of gingivitis dental biofilm-induced and periodontitis among females more than males in group II and group III maybe due to hormonal changes. The present study saw that there are statistically significant differences in clinical findings in the comparison between groups of this study (P ≤ 0.005). Conclusion: We conclude that there is a relation between severity and types of periodontal diseases and the ages and genders of Saudi patients in Aseer and Tabuk regions, Saudi Arabia.展开更多
文摘Background: The variability in the distribution of the null phenotypes of GSTM1 and GSTT1, due to total or partial gene deletion resulting in the lack of the active enzyme, has been reported in different populations, especially in ethnically well-defined groups but not in Tabuk. This study investigated the variability in the distribution of the null phenotypes of GSTM1 and GSTT1 in the population of Tabuk (northwestern part of Saudi Arabia). Method: This study was conducted on 200 subjects of Tabuk—northwestern part of Saudi Arabia among which 100 were chronic smokers and 100 were nonsmokers. The subjects were reporting to hospital for routine checkup. All were without past history of any chronic disease and no significant abnormality. GST genotyping was done by multiplex PCR-based methods. The smoker and control groups were compared using a chi-square test with P GSTM1 deletion homozygosity of 14% and 1% was reported among non smokers and smokers, respectively whereas GSTT1 deletion homozygosity of 28% and 6% was reported among non smokers and smokers, respectively. Our results indicate that there are major differences in allelic distribution of GSTM1 and GSTT1 genes between the two groups investigated. Combined analysis of both genes revealed that 15% of smokers and non smokers harbor the deleted genotype of GSTM1 and 34% of smokers and non smokers harbor the deleted genotype of GSTT1 with significant differences. Conclusion: This study enables selecting subgroups among the general population who are more susceptible to DNA damage and will help genetic studies on the association of GST polymorphisms with disease risks and drug effects in Arab population. Studies with a larger sample size are needed to evaluate and confirm the validity of our results.
文摘Background: Sickle cell disease and sickle cell trait are common erythrocyte disorders that are most often caused by a point mutation (rs334, designated HbS) in the hemoglobin beta gene (HBB);however of this fact, there is extreme variability in occurrence and clinical presentation of sickle cell disease which may be explained by some other genetic changes associated with the gene. In the present study we examined the association between HBB gene polymorphism rs33949930 T>C in the occurrence of sickle cell disease in Saudi Arabia population. Materials and Methods: A case control study of 100 sickle cell disease patients and 100 healthy controls from Tabuk, Saudi Arabia. HBB gene rs33949930 T>C polymorphism was analyzed using Allele specific polymerase chain reaction technique. Results: It was observed that the genotype percentages TT, TC and CC among the patients with sickle cell disease were 63.0%, 35.0% and 2.0% and healthy controls were 68.0%, 27.0% and 5.0% respectively. Allele frequency for T allele was observed to be fT = 0.20 and fT = 0.19, where as for C allele was fC = 0.80 and fC = 0.81 among cases and controls respectively (p = 0.29). Compared to the TT genotype, the odds ratio of 1.4 (95% CI 0.76 - 2.57), risk ratio of 1.2 (95% CI 0.86 - 1.65) and risk difference of 8.4 (-6.66 - 23.38) for heterozygous genotype of HBB rs33949930 T>C was observed in relation to sickle cell disease. In addition, some difference in the laboratory values was observed among sickle cell disease patients with the different variants of HBB gene rs33949930 T>C polymorphism, especially the carriers of heterozygous TC genotype;however, the difference doesn’t reach to statically significant number. Conclusion: Present study suggested that there was not any significant association between HBB gene rs33949930 T>C polymorphism and occurrence of sickle cell disease. However, the heterozygous TC genotype of the polymorphism showed some higher ratios among cases as compared to healthy control group.
文摘Due to global climatic changes, flash floods are followed as a yearly disaster with high magnitude of influence. During the years 1981, 1988, 2010, 2012 and in January 2013, Tabuk city, northwest of Saudi Arabia suffered huge flash floods. These are major factors affecting on the swelling behavior of expansive Tabuk shale. The examined geotechnical properties of the surface and subsurface lithology of the sedimentary deposits distinguished Tabuk city into three zones. The expansive zone is spread in the middle and the non-expansive zones are distributed in the east and west of the city. The Watershed Modeling System (WMS) and Hydrologic Engineering Center (HEC-1) models were used to delineate and identify the drainage system and basin morphometry, where flash floods and accumulation of water might take place. Integration between geotechnical distribution maps of the expansion soil and surface hydrological data in terms of runoff maps was done. It has been identified the whereabouts the soils which have expansion characteristics and areas prone to flooding and surface runoff. They are helpful in defining the hazard zones map. Based on this map, it can be avoided constructions on the risk neighborhoods such as Al Qadsiyah, Al Maseif, Arrwdah, Al Nakhil and Al Rajhi. Also, it can suggest that the western side of Tabuk city is suitable for future urban extension. These results will help planners and citizens to create alternative development scenarios and determine their impact on the future urbanization patterns. Moreover, the direction of surface runoff flow or storm water discharge should be away from the expansion soil areas. Therefore, constructing dams on the outlet of the high-risk basins, south of Tabuk city is an important solution to control flash flood events, as well as increase groundwater recharge.
文摘One main concern of power quality is harmonics because the distorted waveforms of current and voltage have a huge effect on electrical equipment. Due to the continuous increase of grid connected photovoltaic (PV) and nonlinear loads, as a result of the fast development and growth of power electronics application, power quality becomes more important since it introduces harmonics to the power system. This paper presents a power quality study to the isolated northwest grid of Saudi Arabia in presence of PV system and battery storage. Moreover, the study includes nonlinear loads for more analysis regarding harmonics penetration and the design procedure for passive filters to eliminate the harmonics.
文摘Background: Periodontitis is the predominant disease in the oral cavity and there are alterations in the periodontal tissues associated with the aging and gender of the patient. Objective: The present study was designed to assess the impact of age and gender of the patient on severity and types of periodontal diseases among patients from two regions in Saudi Arabia. Materials and Methods: The current study was done on 600 Saudi patients from Aseer and Tabuk regions in Saudi Arabia (50% males and 50% females) and divided into three equal groups (n = 200) according to the patients age: children and young patients (1 - 24 years old), adults patients (25 - 64 years old) and seniors patients (more than 65 years old). Plaque index (PLI), gingival index (GI), periodontal pocket depth (PPD) and clinical attachment loss (CAL) were recorded from all participants. The data were collected and analyzed with SPSS to determine the mean and standard deviation (±SD) and the values of significance (P ≤ 0.005). Results: The results of the present study revealed that 340 patients (56.7%) were affected with gingivitis dental biofilm induced and 260 patients were affected by periodontitis. Gingivitis dental biofilm-induced is especially detected in children and young patients (33.3%), adult patients (16.7%) and seniors patients (6.7%) whereas periodontitis cases were seen among the adult and seniors patients (16.7%) and (26.6%) respectively. Furthermore, the present study displayed the higher severity and prevalence of gingivitis dental biofilm-induced and periodontitis among females more than males in group II and group III maybe due to hormonal changes. The present study saw that there are statistically significant differences in clinical findings in the comparison between groups of this study (P ≤ 0.005). Conclusion: We conclude that there is a relation between severity and types of periodontal diseases and the ages and genders of Saudi patients in Aseer and Tabuk regions, Saudi Arabia.
