Development and Validation of Micro Emulsion High Performance Liquid Chromatography(MELC) Method for the Determination of Nifedipine in Pharmaceutical Preparation

YesMicroemulsion is a stable, isotropic clear solution consisting of oil based substance, water surfactant and cosurfactant. There are two types of microemulsion which are used as a mobile phase; water in oil (w/o) and oil in water (o/w).Microemulsion has a strong ability to solubilize both hydrophobic and hydrophilic analytes, therefore reducing the pre-treatment of the sample which is needed for the complex sample. Recent reports found that separating the analytes by using microemulsion high performance liquid chromatography can be achieved with superior speed and efficiency compared to conventional HPLC modes. In this work, Oil in water (o/w) microemulsion has been used for the determination of nifedipine in pharmaceutical preparation. The effect of each parameter on the separation process was examined. The samples were injected into C18, analytical columns maintained at 30°C with a flow rate 1 ml/min. The mobile phase was 87.1% aqueous orthophosphate buffer 15 mM (adjusted to pH 3 with orthophosphoric acid), 0.8% of octane as oil, 4.5 SDS, and 7.6% 1-butanol, all w/w. The nifedipine and internal standard peaks were detected by UV detection at λ max 237 nm The calibration curve was linear (r2=0.9995) over nifedipine concentrations ranging from 1 to 60 μg/ml (n=6). The method has good sensitivity with limit of detection (LOD) of 0.33 μg/ml and limit of quantitation (LOQ) of 1.005 μg/ ml. Also it has an excellent accuracy ranging from 99.11 to 101.64%. The intra-day and inter-day precisions (RSD %) were <0.45% and <0.9%, respectively

Male reproductive system

The overall reproductive process consists of both the human sex organs which include the male and female reproductive system. The ability to produce off springs that have similar characteristic as their parents is the goal of reproduction. The sexual type of reproduction takes place in human and both male and female reproductive system is required. Male reproductive system is mainly concerned with production of semen (whitish viscous fluid emitted from the male reproductive tract that contains sperm and fluids) and transferring it into the female reproductive tract. In this review, we will discuss the latest findings in the research pertaining the male reproductive system and its contribution towards the research in advancement of reproductive physiology

Effect of hyper-caloric intake on hemodynamic functions and cardiac autonomic control : potential modulation by anti-diabetic drugs

Thesis. M.Sc. American University of Beirut. Department of Pharmacology and Toxicology, Faculty of Medicine 2017. W 4 A848e 2017; Advisor: Dr. Ahmed El-Yazbi, Assistant Professor, Department of Pharmacology and Toxicology ; Co-Advisor: Dr. Fouad Zouein, Assistant Professor, Department of Pharmacology and Toxicology ; Committee members: Dr. Ramzi Sabra, Assistant Dean, Chairperson, Professor, Department of Pharmacology and Toxicology ; Dr. Assaad Eid, Associate Professor, Department of Anatomy, Cell Biology and Physiological Sciences.Includes bibliographical references (leaves 68-86)Diabetes mellitus remains a public health challenge with considerable disease and economic consequences. Mortality and morbidity due to diabetes are related to the poor cardiovascular outcomes. A significant body of research describes the detrimental effect of hyperglycemia on vascular function and the importance of tight blood glucose control in delaying progression of diabetes micro-vascular complications. It is generally agreed that the impact of glycemic control on cardiovascular complications is influenced by the temporal framework in which an acceptable blood glucose level has been achieved, in what became known as the “Legacy effect” or the “Cardiovascular metabolic memory”. On the other hand, recent clinical evidence paints a different picture, whereby treatment with certain anti-hyperglycemic drugs on top of the standard-of-care for diabetes and cardiovascular disease leads to cardiovascular risk reduction, in a manner that is not necessarily tightly linked to their effect on glycemic control.In parallel, recent studies reported cardiovascular abnormalities in animal models of high caloric intake before the development of frank hyperglycemia. We recently developed a rat model of hyper-caloric feeding that was shown to develop vascular dysfunction without changes in blood pressure, serum glucose, or insulin levels. As such, we propose to use this model to characterize early hemodynamic changes occurring in the context of development of diabetes, study the underlying pathological mechanism, track the evolution of these disorders, and examine the effect of early treatment with some of the anti-hyperglycemic drugs with presumed cardiovascular benefit. Control and high calorie fed rat groups will be run side-by-side for 12 weeks. Body weight and caloric intake will be assessed regularly. Non-invasive blood pressure measurement and hemodynamic parameter assessment by echocardiography will be carried out at four-week intervals. Sub-groups of the high calorie fed rats will be give

Image quality and radiation exposure with low-contrast-dose computed tomography angiography of the lower extremities

Introduction: Multidetector computed tomography is the reference standard for the diagnosis of peripheral arterial disease (PAD). The aim of this study is to optimise the image quality of computed tomography (CT) scanning for the diagnosis of PAD with the lowest possible radiation and contrast volume. Material and methods: Seventy-two patients were referred for evaluation of suspected PAD with CT angiography. Patients were randomly assigned to an optimise care dose of kVp - group A, n = 36; 18 men, 18 women; mean age, 63 years with standard deviation 15; range, 20-88 years (contrast volume 80-85 ml was injected automatically with bolus tracking, and group B, n = 36; 18 men, 18 women; mean age, 61 years with standard deviation 16; range, 26-88 years (contrast volume 120-140 ml was injected automatically with bolus tracking). Other scanning parameters were kept constant. Lower extremities vessel enhancement and image noise were quantified, and the signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were calculated. Subjective vessel contrast was assessed by two radiologists in consensus. Result: A total of 16 cases of PAD (22.2%) were found in the evaluated of subjects (10 in group A, and six in group B). All PAD cases were detected by the two readers. There was no significant difference in the size or location of the PAD between the two groups; the average image noise was 19 HU for group A and 16 HU for group B. The difference was not statistically significant (p = 0.183). Overall, the SNR and CNR were slightly higher in group B (25.5 and 24.1, respectively) compared with group A (20 and 17.4, respectively), but those differences were not statistically significant (p = 061 and p = 0.38, respectively). Conclusions: All patients were evaluated by lower extremities CTA protocol allowing similar image quality to be achieved in both groups, with optimised care dose for both protocols, and contrast volume was reduced by 40% in the new protocol group compared to the conventional protocol group

Microcrystalline testing used in combination with Raman micro-spectroscopy for absolute identification of novel psychoactive substances

Two new psychoactive substances, namely 4-methylmethcathinone (mephedrone) and 5,6-methylenedioxy-2-aminoindane (MDAI) were analysed with a novel combination of microcrystalline tests followed by Raman micro-spectroscopy to facilitate their absolute identification. The discrimination power of the proposed combination was successfully demonstrated through the analysis of the positional isomers 2- and 3-methylmethcathinone. The addition of mercury dichloride as a microcrystalline test reagent produced specific microcrystals of each tested analyte. The robustness of the method was evaluated in the presence of common cutting agents (caffeine and benzocaine) as well as on street samples. The crystal lattice structures of mephedrone, 2-methylmethcathinone and MDAI mercury dichloride microcrystals were determined by single crystal X-ray diffraction. This confirmed the presence of both drug and reagent together in the lattice and accounts for the distinct habit of the observed microcrystals. Raman spectra of the formed microcrystals differed from those obtained from their standard salt form by loss and/or gain of some vibrational modes. Particularly important was the appearance of the mercury chloride link to each tested drug molecule which showed as strong bands at low wavenumbers. Its presence was corroborated by its detection in the crystal lattice. It was therefore concluded that microcrystalline testing followed by Raman micro-spectroscopy satisfies the technique combination requirement for psychoactive substances recommended by the Scientific Working Group for the Analysis of Seized Drugs (SWGDRUG) and provides a rapid and cheap analysis route. The proposed technique combination also aids the development of new microcrystalline tests as it allows for confirmation of the uniqueness of the developed microcrystals almost in-situ rather than growing single crystals for often long periods of time needed for single crystal X-ray diffraction analysis

Numerical Investigation of Stress Block for High Strength Concrete Columns

This paper is intended to investigate the stress block for high strength concrete (HSC) using the finite element model (FEM) and analytical approach. New stress block parameters were proposed for HSC including the stress intensity factor (α1) and the depth factor (β1) based on basic equilibrium equations. A (3D) finite element modeling was developed for the columns made of HSC using the comprehensive code ABAQUS. The proposed stress parameters were validated against the experimental data found in the literature and FEM. Thereafter, the proposed stress block for HSC was used to generate interaction diagrams of rectangular and circular columns subjected to compression and uniaxial bending. The effects of the stress block parameters of HSC on the interaction diagrams were demonstrated. The results showed that a good agreement is obtained between the failure loads using the finite element model and the analytical approach using the proposed parameters, as well as the achievement of a close agreement with experimental observation. It is concluded that the use of proposed parameters resulted in a more conservative estimation of the failure load of columns. The effect of the stress depth factor is considered to be minor compared with the effect of the intensity factor

The various effects of Nigella sativa on multiple body systems in human and animals

Nigella sativa (Black seeds) has been recognized as one of the most popular herbs in many parts of the world for centuries. It was used in the world as folk medicine to cure different kinds of diseases. This plant has been considered as one of the main sources of nutrition and healthcare for humans as well as animals. It has been perceived as Kalonji; it is a southwest Asian plant that flowers annually. The seeds and oil of this plant have been used in food; in addition, it has a long history in the making of medicines. In addition to its being a model plant for better realization of gene and chromosome relationship, the plant species is also significant cytogenetically. Plant based system has not been absorbed fully for human health care despite the remarkable advancements in the field of pharmacology. Cumin, as one of the medicinal plants gifted to humans by nature, has a number of potential uses. It has been proved to be a useful herbal medicines that can be used for human health and therefore has been extensively studied and investigated to further discover the advantages of this plant

COLORECTAL CARCINOGENESIS; ROLE OF OXIDATIVE STRESS AND ANTIOXIDANTS

One of the contributory causes of colon cancer is the negative effect of reactive oxygen species on DNA repair mechanism. Currently, there is a growing support for the concept that oxidative stress may be an important etiological factor for carcinogenesis. The purpose of this review is to elucidate the role of oxidative stress in promoting colorectal carcinogenesis and to highlight the potential protective role of antioxidants. Several studies have documentes the importance of antioxidants in countering oxidative stress and preventing colorectal carcinogenesis. However, there are conflicting data in the literature concerning its proper use in humans, since these studies did not yeld definitive results and were performed mostly in vitro on cell population, or in vivo in experimental animal models