Abdel Aziz Ibrahim

Phytosterols as a natural anticancer agent: Current status and future perspective

Phytosterols are naturally occurring compounds in plants, structurally similar to cholesterol. The human diet is quite abundant in sitosterol and campesterol. Phytosterols are known to have various bioactive properties including reducing intestinal cholesterol absorption which alleviates blood LDL-cholesterol and cardiovascular problems. It is indicated that phytosterol rich diets may reduce cancer risk by 20%. Phytosterols may also affect host systems, enabling antitumor responses by improving immune response recognition of cancer, affecting the hormone dependent endocrine tumor growth, and by sterol biosynthesis modulation. Moreover, phytosterols have also exhibited properties that directly inhibit tumor growth, including reduced cell cycle progression, apoptosis induction, and tumor metastasis inhibition. The objective of this review is to summarize the current knowledge on occurrences, chemistry, pharmacokinetics and potential anticancer properties of phytosterols in vitro and in vivo. In conclusion, anticancer effects of phytosterols have strongly been suggested and support their dietary inclusion to prevent and treat cancers.

Impact of aging on cerebral vasoregulation and parenchymal integrity

UNLABELLEDnSufficient vasodilatory and vasoconstrictive reactivity of cerebral arterioles is an important prerequisite for adequate capillary perfusion. To appreciate its capacity during aging and to elucidate its impact on parenchymal integrity we undertook a correlation using ultrasonography and brain MRI. Sixty healthy persons with no stenoses in the carotid and vertebral arteries were examined by transcranial Doppler to assess middle cerebral artery mean flow velocities (MFV) at rest, after 30 s apnea and after 90 s hyperventilation. Young persons, N=20, with a mean age of 24.8 (20-32) were compared with the middle aged, N=20, 54.8 (40-63) and elderly, N=20, 76.2 (69-84). A different cohort of 40 elderly persons, with a mean age of 68.4 (57-85) were evaluated also by MRI using FLAIR and T2-weighted sequences. Their extent of leukoaraiosis measured by the Fazekas scale was correlated with their vasoregulatory capacity.nnnRESULTSnThe steady state MFV in young persons, 71 cm/sec, decreases to 48.1 and to 44.9 cm/sec in the middle and the old aged. The post-apnoic vasodilatation in young persons accelerates the MCA blood velocity by 41.7%, while in middle and old age only by 37.6 and 32.9% respectively. The MCA deceleration post-hyperventilation by 50.2% in young people decreases to 39.1% and to 29.7% respectively in the older categories. The correlation of periventricular hyperintensities and deep white matter lesions was found highest with the index of resistance (0.45, p<0.05) while with the apnoic acceleration and hyperventilatory deceleration it was minimal (0.01 and 0.08 respectively).nnnCONCLUSIONnThe extent of vasoregulatory capacity during aging decreases along with the decreasing basic MFV. Its effect on the initial stages of leukoaraiosis is minimal.

Functional Changes in the Human Auditory Cortex in Ageing

Hearing loss, presbycusis, is one of the most common sensory declines in the ageing population. Presbycusis is characterised by a deterioration in the processing of temporal sound features as well as a decline in speech perception, thus indicating a possible central component. With the aim to explore the central component of presbycusis, we studied the function of the auditory cortex by functional MRI in two groups of elderly subjects (>65 years) and compared the results with young subjects (<lt;30 years). The elderly group with expressed presbycusis (EP) differed from the elderly group with mild presbycusis (MP) in hearing thresholds measured by pure tone audiometry, presence and amplitudes of transient otoacoustic emissions (TEOAE) and distortion-product oto-acoustic emissions (DPOAE), as well as in speech-understanding under noisy conditions. Acoustically evoked activity (pink noise centered around 350 Hz, 700 Hz, 1.5 kHz, 3 kHz, 8 kHz), recorded by BOLD fMRI from an area centered on Heschl’s gyrus, was used to determine age-related changes at the level of the auditory cortex. The fMRI showed only minimal activation in response to the 8 kHz stimulation, despite the fact that all subjects heard the stimulus. Both elderly groups showed greater activation in response to acoustical stimuli in the temporal lobes in comparison with young subjects. In addition, activation in the right temporal lobe was more expressed than in the left temporal lobe in both elderly groups, whereas in the young control subjects (YC) leftward lateralization was present. No statistically significant differences in activation of the auditory cortex were found between the MP and EP groups. The greater extent of cortical activation in elderly subjects in comparison with young subjects, with an asymmetry towards the right side, may serve as a compensatory mechanism for the impaired processing of auditory information appearing as a consequence of ageing.

Palm vitamin E reduces catecholamines, xanthine oxidase activity and gastric lesions in rats exposed to water-immersion restraint stress

BackgroundThis study examined the effects of Palm vitamin E (PVE) and α-tocopherol (α-TF) supplementations on adrenalin, noradrenalin, xanthine oxidase plus dehydrogenase (XOu2009+u2009XD) activities and gastric lesions in rats exposed to water-immersion restraint stress (WIRS).MethodsSixty male Sprague–Dawley rats (200-250u2009g) were randomly divided into three equal sized groups. The control group was given a normal diet, while the treated groups received the same diet with oral supplementation of PVE or α-TF at 60u2009mg/kg body weight. After the treatment period of 28u2009days, each group was further subdivided into two groups with 10 rats without exposing them to stress and the other 10 rats were subjected to WIRS for 3.5 hours. Blood samples were taken to measure the adrenalin and noradrenalin levels. The rats were then sacrificed following which the stomach was excised and opened along the greater curvature and examined for lesions and XOu2009+u2009XD activities.ResultsThe rats exposed to WIRS had lesions in their stomach mucosa. Our findings showed that dietary supplementations of PVE and α-TF were able to reduce gastric lesions significantly in comparison to the stressed control group. WIRS increased plasma adrenalin and noradrenalin significantly. PVE and α-TF treatments reduced these parameters significantly compared to the stressed control.ConclusionsSupplementations with either PVE or α-TF reduce the formation of gastric lesions. Their protective effect was related to their abilities to inhibit stress induced elevation of adrenalin and noradrenalin levels as well as through reduction in xanthine oxidase and dehydrogenase activities.

Effects of Pithecellobium Jiringa Ethanol Extract against Ethanol-Induced Gastric Mucosal Injuries in Sprague-Dawley Rats

Current anti-gastric ulcer agents have side effects, despite the progression and expansion of advances in treatment. This study aimed to investigate the gastroprotective mechanisms of Pithecellobium jiringa ethanol extract against ethanol-induced gastric mucosal ulcers in rats. For this purpose, Sprague Dawley rats were randomly divided into five groups: Group 1 (normal control) rats were orally administered with vehicle (carboxymethyl cellulose), Group 2 (ulcer control) rats were also orally administered with vehicle. Group 3 (positive control) rats were orally administered with 20 mg/kg omeprazole, Groups 4 and 5 (experimental groups) received ethanol extract of Pithecellobium jiringa ethanol extract at a concentration of 250 and 500 mg/kg, respectively. Sixty minutes later, vehicle was given orally to the normal control group, and absolute ethanol was given orally to the ulcer control, positive control and experimental groups to generate gastric mucosal injury. The rats were sacrificed an hour later. The effect of oral administration of plant extract on ethanol-induced gastric mucosal injury was studied grossly and histology. The level of lipid peroxidation, (malondialdehyde—MDA), superoxide dismutase (SOD) and gastric wall mucus were measured from gastric mucosal homogenate. The ulcer control group exhibited severe gastric mucosal injury, and this finding was also confirmed by histology of gastric mucosa which showed severe damage to the gastric mucosa with edema and leucocyte infiltration of the submucosal layer. Pre-treatment with plant extract significantly reduced the formation of ethanol-induced gastric lesions, and gastric wall mucus was significantly preserved. The study also indicated a significant increase in SOD activity in gastric mucosal homogenate, whereas a significant decrease in MDA was observed. Acute toxicity tests did not show any signs of toxicity and mortality up to 5 g/kg. The ulcer protective effect of this plant may possibly be due to its preservation of gastric wall mucus along with increased SOD activity and reduction of oxidative stress (MDA). The extract is non-toxic, even at relatively high concentrations.

Prevalence and factors associated with neck, shoulder and low back pains among medical students in a Malaysian Medical College

BackgroundThe main purpose of the study was to assess the prevalence, body distributions and factors associated with musculoskeletal pain (MSP) among medical students in a private Malaysian medical college.MethodThis cross-sectional study was conducted among 232 medical students in a private medical college using an online questionnaire. The questionnaire was a modified Standardized Nordic Questionnaire focused on neck, shoulder and low back pain in the past week and the past year.ResultsTwo hundred and thirty two medical students responded to the questionnaire out of 642. Mean age was 20.7u2009±u20092.1xa0years. The majority were female (62.9%), Malay (80.6%) and in the preclinical years (72%). One hundred and six (45.7%) of all students had at least one site of MSP in the past week and 151 (65.1%) had at least one site of MSP in the past year. MSP in the past week was associated significantly with the academic year, (OR 2.0, 95% CI 1.15-3.67, Pu2009=u20090.015), history of trauma (OR 2.6, 95% CI 1.2-5.3, Pu2009=u20090.011), family history of MSP (OR 2.1, 95% CI 1.1-3.9, Pu2009=u20090.023) and Body Mass Index (BMI) (Pu2009=u20090.028). MSP in the past year was significantly associated with computer use (Pu2009=u20090.027), daily hours of computer use (medianu2009±u2009IQR (5.0 ±3.0), history of trauma (OR 7.5, 95% CI 2.24-2.56, Pu2009<u20090.01) and family history of MSP (OR 2.5, 95% CI 1.31-4.90, Pu2009=u20090.006). On multivariate analysis, factors associated with MSP during the past week were a family history of MSP (pu2009=u20090.029) and BMI (pu2009=u20090.03). Factors associated with MSP during the past year were being in clinical years (pu2009=u20090.002, computer use (pu2009=u20090.038), and a history of trauma (pu2009=u20090.030).ConclusionMSP among medical students was relatively high, thus, further clinical assessment is needed in depth study of ergonomics. The study results indicate that medical school authorities should take measures to prevent MSP due to factors related to medical school. Students should make aware of importance of weight reduction to reduce MSP.

The effects of palm vitamin E on stress hormone levels and gastric lesions in stress-induced rats

Introduction This study examines the effects of palm vitamin E (PVE) or α-tocopherol (α-TF) supplementation on adrenocorticotropin hormone (ACTH), corticosterone and gastric lesions in rats exposed to water-immersion restraint stress (WIRS). Material and methods Sixty male Sprague-Dawley rats (200-250 g) were divided into three groups. Group I: 20 rats as a control group were given a normal diet. Group II: 20 rats received oral supplementation of PVE at 60 mg/kg body weight. Group III: 20 rats received oral supplementation of α-TF at 60 mg/kg body weight. After the treatment period of 28 days, each group was further subdivided into two groups: 10 rats not exposed to stress, and the other 10 rats subjected to WIRS for 3.5 h. Blood samples were taken to measure the ACTH and corticosterone levels. The rats were then sacrificed and the stomach excised and opened along the greater curvature and examined for lesions. Results Rats exposed to WIRS had lesions in their stomach mucosa. Our findings showed that dietary supplementation of PVE or α-TF was able to reduce gastric lesions significantly in comparison to the stressed controls. The WIRS increased plasma ACTH and corticosterone significantly. Palm vitamin E and α-TF treatments reduced these parameters significantly compared to the stressed controls. Conclusions Supplementation with either PVE or α-TF reduces the formation of gastric lesions, probably by inhibiting the elevation of ACTH and corticosterone levels induced by stress.

Interactions of atenolol with alprazolam/escitalopram on anxiety, depression and oxidative stress

Anxiety and depression are highly comorbid disorders possibly sharing a common neurobiological mechanism. The dysfunction of serotoninergic, noradrenergic and dopaminergic neurotransmission, abnormal regulation in the hypothalamic-pituitary-adrenal axis (HPA), disturbance of cellular plasticity including reduced neurogenesis, or chronic inflammation connected with high oxidative damage play a crucial role in the development of anxiety and depression. The present study was aimed to investigate the effects of atenolol alone and in combination with alprazolam/escitalopram on anxiety, depression and oxidative stress. Wistar albino rats were subjected to 21 day treatment of drugs then exposed to elevated-plus maze (EPM) and modified forced swim test (MFST), and oxidative stress markers were estimated in isolated brain tissue of all groups. The results indicated that atenolol in combination with alprazolam/escitalopram exhibited antidepressant effects by significantly decreasing the immobility and increasing the swimming behavior in the MFST and anti-anxiety effects by increasing the percentage preference and number of open arm entries as well as time spent in open arm in EPM. Pretreatment with atenolol alone and combination with alprazolam/escitalopram also ameliorated tissue glutathione (GSH) and decreased malondialdehyde (MDA) level significantly which explore antioxidant properties of drugs, and combination augments the therapeutic response of monotherapy in depression. In conclusion behavioral and biological findings indicate that the combination of atenolol with alprazolam/escitalopram has the potential of being highly efficacious in treating anxiety and depressive disorders as well as oxidative stress.

Ophthalmic Parasitosis: A Review Article

Ocular parasitosis in human is more prevalent in geographical areas where environmental factors and poor sanitary conditions favor the parasitism between man and animals. Lesions in the eye can be due to damage directly caused by the infectious pathogen, indirect pathology caused by toxic products, or the immune response incited by infections or ectopic parasitism. The epidemiology of parasitic ocular diseases reflects the habitat of the causative parasites as well as the habits and health status of the patient. An ocular examination may provide clues to the underlying disease/infection, and an awareness of the possibilities of travel-related pathology may shed light on an ocular presentation. This paper is a comprehensive review of the parasitic diseases of the eye. The majority of the clinically important species of parasites involved in eye infection are reviewed in this paper. Parasites are discussed by the disease or infection they cause.

Frequencies of glutathione s-transferase (GSTM1, GSTM3 and GSTT1) polymorphisms in a Malaysian population

Introduction Glutathione S-transferase (GST) is a xenobiotic metabolising enzyme (XME), which may modify susceptibility in certain ethnic groups, showing ethnic dependent polymorphism. The aim of this study was to determine GSTM1, GSTM3 and GSTT1 gene polymorphisms in a Malaysian population in Kuala Lumpur. Material and methods Blood or buccal swab samples were collected from 137 Form II students from three schools in Wilayah Persekutuan Kuala Lumpur. Genotyping was done by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Results Glutathione-S-transferase GSTM3 gene frequencies were 89% for AA, 10% for AB and 1% for BB. The gene frequencies for deleted GSTM1 and GSTT1 were 66% and 18% respectively. Conclusions This study suggested that the Malay population is at risk for environmental diseases and provides the basis for gene-environment association studies to be carried out.