Investigation of the potential anti-urolithiatic activity of Alhagi maurorum (Boiss.) grown wild in Al-Ahsa (Eastern Province), Saudi Arabia.

The potential of Alhagi maurorum (Boiss.) aqueous extract (AME), used in traditional medicine for treatment or prevention of urolithiasis, to dissolve calcium oxalate stones in vitro was evaluated. In order to determine the litholytic potential of the extract, Calcium oxalate urinary stones were incubated during 12 weeks under continuous shaking in the presence of AME, Rowanix or NaCl 9 g/mL solution were used as controls. After the incubation period, the residual weight of the treated calculi was determined and the rate of dissolution was calculated. The medium pH variation was measured and changes in the calcium oxalate crystals at the stone surface were assessed using a scanning electron microscope (SEM). The results showed a significant dissolution effect for the extract on the kidney calculi during the experimentation period. At the end of the experiment, the percentages of calculi weight decrease were 41.23, 4.97 and 55.67% for the extract, NaCl solution and Rowanix, respectively. Gas Chromatography analysis revealed mainly the presence of the following phyto-compounds: Cyclopropenone, 2,3-diphenyl; 1-Nonadecanol; methyl-alpha-D-mannopyranoside; cis-9-Hexadecenal. These compounds unarguably play crucial roles in the health care system especially in cancer treatment and many other diseases including urolithiasis. The urinary stone dissolution, independent of medium pH, could be attributed to formation of complexes between the phytochemical compounds in the extract and the calculi.

Monitoring metal levels in water and multiple biomarkers in the grouper ( Epinephelus tauvina) to assess environmental stressors on the Arabian Gulf coast of Saudi Arabia.

In this field study, the levels of heavy metals (Pb, Fe, Co, Cu, and Zn) in water and a suite of biochemical and histological biomarkers in the grouper ( Epinephelus tauvina) were assessed at four sites in the Arabian Gulf. Samples were taken from a relatively non-urban reference site, called Salwa (S1), and three effluent-dominated sites, namely Al-aziziyah in southern Dammam city (S2), the Al-Jubail coast (S3), and Manifa (S4). Toxic metals, namely Pb and Co (at all sites) and Fe (at S3), were elevated in water samples relative to the internationally permissible limits. In fish, induced levels of heat shock protein 70 (HSP70) in the liver at S3 and S4 were higher than those of the reference fish at S1. Additionally, the level of the lipid peroxidation (LPO) product (malondialdehyde (MDA)) was significantly increased in gills (at S3) and liver (at S2 and S3). There was an inhibition of catalase activities in the gills of fish from S2 to S4 and significantly higher activity levels of superoxide dismutase in the gills of fish from S4. Histopathological features such as aneurysms in gill vessels, deformed gill lamellae, increases in liver melano-macrophage centers, and hepatocellular necrosis were most abundant at sites where significant pollution problems exist (i.e. S2-S4). The results reveal that the eastern coast of Saudi Arabia, in the Arabian Gulf, is still contaminated, as indicated by elevated HSP70, LPO content and numbers of histological lesions, and that monitoring of contaminants and their effects should be continued in this region.

Time-of-flight-secondary ion mass spectrometry and cyclic voltammetry studies of self-assembly of dodecanethiol on a nanoporous gold surface.

Preparation of a nanoporous gold surface by dealloying (etching) of a 585 gold plate (58.5% Au, 30% Ag, and 11.5% non-noble metals) was studied by applying acidic and thermal treatment of the gold plate. The gold plate surface was studied before and after the etching process using different analytical techniques like field emission scanning electron microscope (FE-SEM) with an energy dispersive X-ray spectroscopy analyzer (EDX), cyclic voltammetry (CV), and time-of-flight-secondary ion mass spectrometry (TOF-SIMS). CV analysis of the gold surface has shown that overnight etching with warm nitric acid increases the surface area 20 times higher than before etching. FE-SEM analysis has shown that a nanoporous gold surface with pore diameter ≤100 nm was obtained. SIMS depth profile analysis and EDX analysis have shown that the nanoporous gold surface was obtained as a result of removing the silver and copper from the first layers of the plate. The nanoporous gold surface was used as a substrate for self-assembly of dodecanethiol and has shown a higher extraction efficiency than the unetched gold alloy.

Development of a new porous gold SPME fiber for selective and efficient extraction of dodecanethiol followed by GC-MS analysis.

The efficiency of a porous gold fiber used for solid-phase microextraction (PG-SPME) was investigated for the extraction of dodecanethiol out of ethanolic solution. A commercially available standard SPME (polydimethylsiloxane, carboxen, divinylbenzene-PDMS-Carb-DVB) was used as a reference to compare the extraction efficiency and selectivity of dodecanethiol with the PG-SPME fiber. The porous gold SPME fiber allowed the analysis of self-assembled monolayers on gold by gas chromatography-mass spectrometry (GC-MS). The PG-SPME fiber showed a five times higher peak area for dodecanethiol in GC-MS compared to the standard PDMS-Carb-DVB fiber.