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Clinical and Experimental Medical Journal
Authors:
Saleh Alqasoumi
,
Mohammed Al-Dosari
,
Mohammed Al-Sohaibani
,
Tawfeq Al-Howiriny
,
Mohammed Al-Yahya
, and
Syed Rafatullah

Abstract

Hibiscus sabdariffa L. (Roselle) is a vegetable known to possess various therapeutic properties. We evaluated the anti-ulcerogenic property of ethanolic extract of dried calyces (EEHS) in different ulcer models in Wistar albino rats. The extract at 250 and 500 mg/kg body weight, orally has a significant effect in cold restraint stress, pylorus ligation, necrotizing agents (80% ethanol, 0.2 M NaOH and 25% NaCl) and indomethacin-induced gastric ulcer models. The extract showed an ability to significantly protect against gastric mucosal injury in all models used. Furthermore, EEHS has significantly decreased the basal gastric acid secretion, as well as significantly increased gastric wall mucus secretion (GWM) and non-protein sulfhydryl (NP-SH) concentrations in gastric tissue. Whereas, the extract significantly reduced the ethanol-induced elevated levels of malondialdehyde (MDA) in the rat stomach. These pharmacological and biochemical findings were further supported by the histological assessment of the stomach. The phytochemical constituents present in the H. sabdariffa calyces may contribute to its anti-ulcer activity through one or more mechanism(s), including the antisecretory and antioxidant nature of the extract.

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Abstract

Higher heating value (HHV) is probably the most important property of the fuels. Bomb calorimeter and derived empirical formulae are often used for accurate determination of HHV of fuels. A useful empirical equation was derived to estimate HHV of petro-diesels from their C and H contents: HHV (in MJ/kg) = 0.3482(C) + 1.1887(H), r 2 = 0.9956. The derived correlation was validated against the most common formulae in the literature, Boie and Channiwala–Parikh correlations. Accordingly, accurate determination of C and H contents is essential for estimation of HHV and avoids using a bomb calorimeter. However, accurate estimation of C and H contents requires using expensive and laborious gas chromatographic techniques. In this work, chemometry offered a simple method for HHV determination of petro-diesels without using bomb calorimeter or even gas chromatography. PLS-1 calibration was used instead of gas chromatography to find C and H contents from the non-selective mid-infrared (MIR) spectra of petro-diesels, HHV was then estimated from the earlier empirical equation. The proposed method predicts HHV of petro-diesels with high accuracy and precision, with modest analysis costs. The present method may be extended to other fuels.

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Hungarian Medical Journal
Authors:
Yousif Asiri
,
Abdlatif Al-Dhawailie
,
Saleh Alqasoumi
,
Mohammed Al-Yahya
, and
Syed Rafatullah

From prehistoric times, herbal medicine has been used by various communities and civilizations throughout the world. This trend continues to the present day. For the past several decades, herbal medicines have been increasingly consumed by people without prescription. They are traditionally considered as harmless since they belong to natural sources. Herbal formulations which have reached widespread acceptability as therapeutic agents are such as antidiabetics, anti-arthritics, aphrodisiacs, hepatoprotectives, cough remedies, memory enhancers and adoptogens. However, with a more efficient case reporting of adverse drug reactions, the hazards of herbal medicines as self prescriptions have been well recorded. In this regard the World Health Organization (WHO) has set specific guidelines for the assessment of the safety, efficacy and quality of herbal medicines. The purpose of pharmacovigilance is to detect, assess and understand, and to prevent the adverse effects or any other possible drug-related problems, which is not only confined to chemical drugs, but extended to herbal, traditional and complementary medicines, biologicals, vaccines, blood products and medical devices. Herbal pharmacovigilance should be implemented and authorities should record apart from existing information on various aspects of the single herb and/or compound herbal formulations on concomitant use with chemical drugs, adverse drug reaction, delayed or acute toxic effects, allergies etc. Most over-the-counter herbal products like ginseng have drawn great public attention but there are several case reports mentioned in the literature of adverse drug reactions of herbal drugs which are generally considered safe. In this paper, we have succinctly reviewed the various aspects associated with the pharmacovigilance of herbal medicines ranging from the pathophysiology to the various clinical elements of adverse drug reactions associated with herbal medicine.

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