A review of the scorpion fauna of Saudi Arabia

The scorpions of Saudi Arabia were surveyed in the major regions of Jazan, Al-Medina, Al-Baha, Hail, and Riyadh, in addition to nine provinces surveyed more superficially. Jazan (1,440 specimens) had 10 buthids and two scorpionid species and subspecies; Al-Medina (867) had seven buthid and two scorpionid species and subspecies, one of which, the scorpionid Scorpio maurus (palmatus?), needs further confirmation of identity. The Al-Baha region (2421 specimens) contained five buthids and two scorpionid species and subspecies; Hail (1,921) had eight buthid and two scorpionid species and subspecies - the most common subspecies here was Scorpio maurus kruglovi. Androctonus crassicauda and Leiurus quinquestriatus were only found in Hail and Al-Baha; Androctonus bicolor was newly recorded in Hail and Riyadh. Riyadh (4,164 specimens) had nine buthid, one scorpionid and at least two hemiscorpiid species and subspecies. The Saudi fauna was found to comprise at least 28 species and subspecies of the families Buthidae, Scorpionidae and Hemiscorpiidae.Keywords: Buthidae, Scorpionidae, Diplocentrida

Association of tumor necrosis factor-α and -β gene polymorphisms in inflammatory bowel disease

Ebtissam Saleh Al-Meghaiseeb,1 Abdulrahman A Al-Robayan,1 Mulfi Mubarak Al-Otaibi,1 Misbahul Arfin,2 Abdulrahman K Al-Asmari2 1Department of Gastroenterology, 2Research Centre, Prince Sultan Military Medical City, Riyadh, Saudi Arabia Abstract: Inflammatory bowel disease (IBD) is a complex, multifactorial, chronic inflammatory disorder of the gastrointestinal tract in which immune dysregulation caused by genetic and/or environmental factors plays an important role. The aim of this case–­control study was to evaluate the association of tumor necrosis factor-alpha (TNF-α) (308) and -β (+252) polymorphisms with susceptibility of IBD. A total of 379 Saudi subjects including 179 IBD patients (ulcerative colitis (UC) =84 and Crohn’s disease (CD) =95) and 200 age- and sex-matched healthy controls were recruited. TNF-a and TNF-b genes were amplified using an amplification refractory mutation systems polymerase chain reaction methodology to detect TNF-α (–308) and -β (+252) polymorphisms. The frequency of the GA genotype of TNF-α (–308G/A) was higher, and the frequencies of the GG and AA genotypes were significantly lower in IBD patients compared with those in controls, indicating that genotype GA-positive individuals are susceptible to IBD and that the GG and AA genotypes exert a protective effect. The frequency of allele A of TNF-α (–308G/A) was significantly higher and that of allele G was lower in IBD patients compared with those in controls, indicating an association of allele A with IBD risk in Saudi patients. On stratification of IBD patients into UC and CD, an almost similar pattern was noticed in both the groups. The results of TNF-β (+252A/G) polymorphisms showed a significant increase in the frequency of the GG genotype in IBD patients, suggesting a positive association of GG genotype with IBD risk. On stratification of IBD patients into UC and CD, the genotype GG of TNF-β was associated with susceptibility risk to UC but not CD. The frequencies of alleles and genotypes of both TNF-α and-β polymorphisms are not affected by sex or type of IBD (familial or sporadic). TNF-α (–308G/A) and TNF-β (+252A/G) polymorphisms are associated with risk of developing IBD in Saudi population. Keywords: tumor necrosis factor, polymorphism, inflammatory bowel disease, Saudis, Crohn’s disease, ulcerative colitis&nbsp

Evaluation of an experimental silane primer system in promoting adhesion between orthodontic bracket and ceramic

The aim of the study was to evaluate in vitro the effect of an experimental silane primer system on the adhesion strength of metallic orthodontic brackets bonded to a ceramic surface. For this purpose, a total of 180 glazed ceramic porcelain fused to metal (PFM) veneer were randomly assigned into 2 groups of 90 specimens, according to the primer used. Each group was further divided into 3 subgroups according to the surface treatment to be received, thus there were 6 study groups; three with 3-acryloxypropyltrimethoxysilane (ACPS) silane primer, namely 1a (pretreatment with hydrofluoric acid, HF), 1b (pretreatment with grit-blasting) and 1c (pretreatment with tribochemical silica-coating) and 3 with a novel silane system (ACPS+bis-1,2(triethoxysilyl) ethane (BTSE)) assigned as 2a (HF), 2b (grit-blast), and 2c (tribochemical silica coating). The samples were evaluated for surface roughness (Ra) before and after surface conditioning. Next, 15 samples from each subgroups were subjected to thermo-cycling and remaining 15 samples served as the baseline (n = 15). Adhesion strength (the shear bond strength, SBS) was recorded using a universal testing machine. Debonding failure types were classified according to the adhesive remnant index (ARI). Contact angles of the primers were measured. Data were analyzed by ANOVA and Tukey’s multiple comparison post hoc analysis. The highest SBS at baseline (26 8+1 7 MPa) and after thermocycling (24 6+1 7 MPa) was observed in group 2c, and the lowest (9 6+1 5 MPa and 4 5+1 1 MPa) was found in group 1a. Specimens pretreated with tribochemical silica-coating exhibited the highest Ra and the lowest Ra was observed in HF treated specimens. The application of experimental silane primer system on specimens pretreated with tribochemical silica-coating demonstrated increased adhesion of orthodontic brackets making it an excellent choice in orthodontic bonding for a relatively long term use