Vitamin D and Its Deficiency in Saudi Arabia

Vitamin D is a hot topic that has attracted attention over the past 10 years, especially since a large proportion of people suffer from this nutrient deficiency. Vitamin D deficiency is estimated to be about 1 billion people all over the world and 50% in Asia and the Middle East. Saudi Arabia has also demonstrated a high prevalence of vitamin D deficiency among healthy Saudi individuals. This chapter provides, in detail, a clear and understandable identification of vitamin D, its function, source, synthesis, metabolism, status, and deficiency. The chapter also focuses on studying vitamin D deficiency in Saudi Arabia based on PubMed’s initial research criteria

Exploration of nutraceutical potential of herbal oil formulated from parasitic plant

Background: Cuscuta reflexa (C. reflexa) is a parasitic climber of medicinal importance. The present study was aimed to evaluate the nutraceutical potential of C. reflexa stems collected from different hosts and to evaluate the role of the herbal formulation in dandruff, hair fall control as well as hair growth promoter.Materials and Methods: Hair formulations of C. reflexa collected from different host plants were prepared in the form of herbal oils (10% w/v). C. reflexa stems were extracted using mustard oil as base oil by using direct boiling technique. Prepared oil was studied as hair tonic. The experimental protocols used were anti-dandruff hair growth activity, as well as hair fall reduction. Herbal hair oils versus mustard oil were evaluated by applying oils on human volunteers with hair fall and dandruff problem whereas promotion of hair growth activity was conducted on rats. The formulated oils were also characterised for proximate analysis, physiochemical composition, as well as antimicrobial activity.Result: The test oils of C. reflexa collected from Azadiracta indica and Zizyphus jujuba were effective in the promotion of hair growth, dandruff control, as well as reduction in hair fall activity.Conclusion: All the formulated oils showed potent antimicrobial activity against all selected strains of bacteria and fungi.Keywords: Cuscuta reflexa, host plants, Hair fall, Dandruff, Combing assay, Herbal hair oil, Hair growth activity

Cardiac acceleration as a marker of vagal withdrawal in heart rate control during exercise in humans

Objective: To investigate whether the time rate of change in heart rate i.e. cardiac acceleration, during aerobic exercise in human subjects could be used to differentiate vagal withdrawal from sympathetic stimulation.Methods: Fifteen male subjects exercised on a bicycle ergometer at 50 Watts (Step 1), then 100 Watts (Step 2), for 2 minutes each.Results: Heart rate (HR) was monitored from a resting value (mean +/- SD) of 80.3 +/- 12.9 to 113.8 +/- 13.6 beats min-1 in Step 1. In Step 2 exercise, HR increased from 113.8 +/- 13.6 to 145 +/- 20 beats min-1. At the initiation of Step 1, a rapid acceleration of HR was observed in the form of an overshoot response. In contrast to Step 1, a small overshoot response of cardiac acceleration was observed during Step 2. The difference between the mean cardiac acceleration at 10 seconds in Steps 1 and 2 was significant (2.40 +/- 0.19 and 0.71 +/- 0.12 beats min-1 sec-1, p \u3c 0.0001).CONCLUSION: The initial vagal withdrawal of exercise-induced tachycardia, as a frontline adaptive mechanism, can be indirectly identified from HR transients using cardiac acceleration as a new marker

Analysis of Finite Microstrip Structures Using an Efficient Implementation of the Integral Equation Technique

An efficient numerical implementation of the Integral Equation technique (IE) has been developed for the analysis of the electrical characteristics of finite microstrip structures. The technique formulates a volume version of the IE for the finite dielectric objects, and a standard surface IE technique for the metallic areas. The system of integral equations formu- lated are solved with special numerical techniques described in this paper. The input impedances of several microstrip antennas have been computed, showing good agreement with respect mea- surements. The technique has shown to be accurate even for complex geometries containing several stacked dielectric layers. The radiation patterns of the structures have also been com- puted, and measured results from real manufactured hardware confirm that backside radiation and secondary lobes are accurately predicted by the theoretical model. The paper also discuss a suitable excitation model for finite size ground planes, and investigates the possibilities for an independent meshing of the metallic areas and the dielectric objects inside a given geom- etry. The practical value of the approach derived is that microstrip circuits can be designed minimizing the volume and size of the dielectric substrates.This work has been supported bythe Spanish National Project ESP2001-4546-PE, and RegionalSeneca Project PB/4/FS/02

Weighing the Milky Way

We describe an experiment to measure the mass of the Milky Way galaxy. The experiment is based on calculated light travel times along orthogonal directions in the Schwarzschild metric of the Galactic center. We show that the difference is proportional to the Galactic mass. We apply the result to light travel times in a 10cm Michelson type interferometer located on Earth. The mass of the Galactic center is shown to contribute 10^-6 to the flat space component of the metric. An experiment is proposed to measure the effect.Comment: 10 pages, 1 figur

A Lie Symmetry Classification of a Nonlinear Fin Equation in Cylindrical Coordinates

The nonlinear fin equation in cylindrical coordinates is considered. Assuming a radial variable heat transfer coefficient and temperature dependent thermal conductivity, a complete classification of these two functions is obtained via Lie symmetry analysis. Using these Lie symmetries, we carry out reduction of the fin equation and whenever possible exact solutions are obtained

Mining biosynthetic gene clusters in Virgibacillus genomes

BACKGROUND: Biosynthetic gene clusters produce a wide range of metabolites with activities that are of interest to the pharmaceutical industry. Specific interest is shown towards those metabolites that exhibit antimicrobial activities against multidrug-resistant bacteria that have become a global health threat. Genera of the phylum Firmicutes are frequently identified as sources of such metabolites, but the biosynthetic potential of its Virgibacillus genus is not known. Here, we used comparative genomic analysis to determine whether Virgibacillus strains isolated from the Red Sea mangrove mud in Rabigh Harbor Lagoon, Saudi Arabia, may be an attractive source of such novel antimicrobial agents. RESULTS: A comparative genomics analysis based on Virgibacillus dokdonensis Bac330, Virgibacillus sp. Bac332 and Virgibacillus halodenitrificans Bac324 (isolated from the Red Sea) and six other previously reported Virgibacillus strains was performed. Orthology analysis was used to determine the core genomes as well as the accessory genome of the nine Virgibacillus strains. The analysis shows that the Red Sea strain Virgibacillus sp. Bac332 has the highest number of unique genes and genomic islands compared to other genomes included in this study. Focusing on biosynthetic gene clusters, we show how marine isolates, including those from the Red Sea, are more enriched with nonribosomal peptides compared to the other Virgibacillus species. We also found that most nonribosomal peptide synthases identified in the Virgibacillus strains are part of genomic regions that are potentially horizontally transferred. CONCLUSIONS: The Red Sea Virgibacillus strains have a large number of biosynthetic genes in clusters that are not assigned to known products, indicating significant potential for the discovery of novel bioactive compounds. Also, having more modular synthetase units suggests that these strains are good candidates for experimental characterization of previously identified bioactive compounds as well. Future efforts will be directed towards establishing the properties of the potentially novel compounds encoded by the Red Sea specific trans-AT PKS/NRPS cluster and the type III PKS/NRPS cluster

EXPLORATION OF NUTRACEUTICAL POTENTIAL OF HERBAL OIL FORMULATED FROM PARASITIC PLANT

Background: Cuscuta reflexa (C. reflexa) is a parasitic climber of medicinal importance. [pls state study objective] Materials and Methods: Hair formulations of C. reflexa collected from different host plants were prepared in the form of herbal oils (10% w/v). C. reflexa stems were extracted using mustard oil as base oil by using direct boiling technique. Prepared oil was studied as hair tonic. The experimental protocols used were anti-dandruff hair growth activity, as well as hair fall reduction. Herbal hair oils versus mustard oil were evaluated by applying oils on human volunteers with hair fall and dandruff problem whereas promotion of hair growth activity was conducted on rats. The formulated oils were also characterised for proximate analysis, physiochemical composition, as well as antimicrobial activity. Result: The test oils of C. reflexa collected from Azadiracta indica and Zizyphus jujuba were significantly effective in the promotion of hair growth, dandruff control, as well as reduction in hair fall activity. Conclusion: All the formulated oils showed potent antimicrobial activity against all selected strains of bacteria and fungi