Serotonin syndrome: An often-neglected medical emergency.

Optimum serotonin level in the serotonergic synapses of the central nervous system (CNS) is related to mood, behavior, and sleep. Serotonin syndrome (SS) is a rare yet very dangerous adverse effect resulting from increased serotonin in CNS. The diagnosis of SS is based on the presence of clinical symptoms, which can include agitation, confusion, rapid heart rate, high blood pressure, dilated pupils, muscle rigidity, tremors, sweating, and diarrhea. SS is invariably caused by inadvertent use of serotonergic medicines. There is an ever-growing list of medicines that are associated with the risk of SS. Some of the common classes of drugs that can contribute to the development of SS include selective serotonin reuptake inhibitors, serotonin-norepinephrine reuptake inhibitors, monoamine oxidase inhibitors, tricyclic antidepressants, stimulants (e.g., amphetamines and cocaine), lithium, opioids, drugs used for recreational purposes like ecstasy Methylenedioxymethamphetamine (MDMA), and some herbal supplements (e.g., St. John's Wort). SS can occur when these medications are taken alone or in combination, especially when a new medication is added, or the dose of an existing medication is changed. The management of SS typically involves discontinuing the use of the substance that caused the excess serotonin levels and providing supportive care, such as intravenous fluids and electrolytes. In severe cases, benzodiazepines may be used to control agitation and muscle rigidity, while serotonin antagonists, such as cyproheptadine, may be used to reduce serotonin levels. The literature review points to a general unawareness among physicians about the condition or drugs associated with it. Consequently, this potentially fatal condition is overlooked. There is a need for regular information updates and reminders to all those who prescribe medications to the patients.

Neuropsychiatric Disorders Associated With Vitamin B12 Deficiency: An Autobiographical Case Report.

Vitamin B12 is an essential vitamin. Among its many functions is its crucial role as a coenzyme in a step of normal synthesis of myelin. Likewise, it is a vital coenzyme in the synthesis of neurotransmitters. Therefore, it is no surprise that vitamin B12 deficiency is linked to a spectrum of neuropsychiatric disorders. Most physicians can quickly pick up typical pernicious anemia, but very few remember the association of vitamin B12 with neuropsychiatric disorders. In this case report, the author presents his own experience of neuropsychiatric disorder (presenting as carpal tunnel syndrome along with anxiety) related to vitamin B12 deficiency with a strong recommendation to include vitamin B12 in the initial set of laboratory investigations suggested for patients over 40 years of age presenting with neuropsychiatric disorders.

Effect of fasting after exercise on blood lactate clearance in untrained male volunteers.

OBJECTIVES: To determine the effect of fasting immediately after exercise on blood lactate clearance. METHODS: This study was conducted at College of Medicine, Dammam University, KSA. Untrained male volunteers (n = 26) between 18-23 years of age were divided into two equal groups; fasting and non-fasting. After an overnight fasting both groups were made to exercise on a bicycle ergometer starting with 100 watt resistance with 25 watt increment after every 2 minutes until voluntary exhaustion. The fasting group was then asked to continue fasting 30 minutes after exercise, while the non-fasting group was given 600 ml of carbohydrate-rich (about 16g per 100 ml) drink immediately after exercise. We measured the blood lactate level before, immediately after, and 30 minutes after exercise in both the groups. RESULTS: A significant (p < 0.001) increase in mean blood lactate level was observed in both the groups immediately after exercise as compared to the baseline means. Similarly there was a significant (p < 0.001) drop of lactate level in both the groups 30 minutes after exercise as compared with the blood lactate level immediately after exercise. There was a significant (p < 0.001) difference between the number of subjects with a blood lactate drop of more than 50% between the two groups (84.61% of subjects in the fasting group, versus 46.15% in the non-fasting group). CONCLUSION: Fasting after exercise accelerates lactate clearance from blood, probably by utilizing gluconeogenesis pathway.

Energy drinks consumption pattern, perceived benefits and associated adverse effects amongst students of University of Dammam, Saudi Arabia.

BACKGROUND: There are safety concerns about energy drinks alongside marketing claims of physiological and behavioural benefits. There is no scientific data about usage of energy drinks in Saudi Arabia. This study determined consumption patterns of energy drinks as well as perceived benefits and side effects amongst students at a Saudi university. METHODS: This study was carried out in students of University of Dammam from October to December 2010. A questionnaire about energy drink use, reasons for use, benefits and side effects experienced was distributed amongst the university students. Frequencies of responses and differences between male and female students were analysed. RESULTS: A total of 412 students (282 males and 130 females) responded, out of whom 54.60% males and 26.15% female students were energy drink users. Mean age at first use was significantly (p<0.05) less in female students. Inspirations for first time use were friends (both genders) and curiosity (males mainly). Most students did not have a fixed frequency of use. The commonest reasons for use were company of friends, to keep awake, for more energy and for better performance in driving, sports or exams. Amongst many the commonest (p<0.05) benefit reported was ability to stay awake longer. The students reported a number of adverse effects. Increased urination and insomnia were the commonest in males and females respectively. Only 36.70% males and 14.28% females never experienced an adverse effect. CONCLUSION: A significant proportion of students at university of Dammam use energy drinks, they have reported a number of effects (perceived as benefits) along with a variety of adverse effects.

Histological Changes in Renal, Hepatic and Cardiac Tissues of Wistar Rats after 6 Weeks Treatment with Bipyridine Gold (III) Complex with Dithiocarbamate Ligands.

Bipyridine gold (III) dithiocarbamate compounds are Gold-III complexes with promising cytotoxic properties. In this study, the subacute toxicity of a Gold (III) complex with dithiocarbamate ligand was evaluated. In the acute toxicity component, an initial LD50 (38.46 mg/kg) was calculated by the administration of 50, 100, 200, 400, and 800 mg/kg of the compound to five groups of rats, respectively (n = 4 each). The sixth group was the control. The sub-acute toxicity component comprised the control group A (n = 6) and the study groups B (n = 10) and C (n = 4), which were administered 1 mL distilled water, 1/10 LD50 (3.8 mg/kg), and 1/5 LD50 (7.6 mg/kg), respectively, daily for 6 weeks. The alive animals were then sacrificed. Autopsy; preservation of renal, hepatic and cardiac tissue in buffered formalin; histopathological processing; microscopic evaluation; and comparison with the controls were sequentially conducted. In the subacute toxicity study at dosages of 3.8 mg/kg and 7.6 mg/kg, the renal tubules remained unaffected with no necrosis or vacuolization. Mild to moderate renal interstitial, hepatic capsular, lobular and portal inflammation along with mild focal hepatic vacuolization were present. At 3.8 mg/kg, the cardiac muscle fibers were unremarkable in 80% (n = 8) of the specimens, with mild focal hyalinization in 20% (n = 2) of the specimens. The same was observed in 50% (n = 2) of the specimens at 7.6 mg/kg. Variable congestion was evident in all of the groups. In the subacute toxicity study, the absence of renal tubular necrosis or vacuolization, the presence of mild inflammatory hepatic and renal alterations, and predominantly unremarkable cardiac muscle fibers suggest that Bipyridine gold (III)-dithiocarbamate is safe in animal studies and is a potential candidate for clinical trials.

Correlation of eosinophil derived neurotoxin with airway resistance in asthmatics.

OBJECTIVE: To determine the correlation of EDN with lung function tests (FVC, FEV1, FEV1/FVC and FEF25-75%) in asthmatics and to compare these with matched controls. METHODS: This study was carried out at Army Medical College & Military Hospital, Rawalpindi, Pakistan. Forty four asthmatic patients and equal number of matching controls were selected. Lung function tests were done by using compact spirometer. Severity of asthma was graded according to the American Thoracic Society (ATS) "Asthma severity code and classification chart." Venous blood was used for estimation of eosinophil count while serum was used for estimation of EDN by ELISA. Correlation between EDN and various lung functions were calculated. RESULTS: The asthmatic patients had significantly more eosinophil count (p<0.001) and Serum EDN levels (p<0.001) than the controls. A significant correlation (r = 0.934, p<0.001) was found between eosinophil count and EDN. A significant correlation between absolute eosinophil count and some of the lung functions [% predicted FEV1 (r = -0.908, p<0.001) and FEV1/FVC (r = -0.830, P<0.001)] was found. A similar significant correlation was found between EDN and some of the lung functions [% predicted FEV1 (r = -0.855, p<0.001) and FEV1/FVC (r = -0.814, P<0.001)]. Absolute eosinophil count and EDN increased significantly (p<0.001) with increasing severity of asthma. CONCLUSION: Serum EDN has significant correlation with changes in lung functions and severity of asthma.

Association Between FeNO, Total Blood IgE, Peripheral Blood Eosinophil and Inflammatory Cytokines in Partly Controlled Asthma.

BACKGROUND: Fractional exhaled nitric oxide (FeNO) is a convenient to use biomarker of airway inflammation. However, the mutual relationship between FeNO, peripheral blood eosinophil, total immunoglobulin E (IgE) and inflammatory cytokines showed some controversy. OBJECTIVE: This study was carried out to determine the accuracy of peripheral blood eosinophil and total IgE to detect eosinophilic airway inflammation as determined by two FeNO cutoff points. The correlation between FeNO, peripheral blood eosinophil, total IgE and certain inflammatory cytokines was also examined. METHODS: Seventy-six patients with partly controlled asthma performed the following tests on the same day: FeNO, pulmonary function tests (PFTs), peripheral blood eosinophils, total IgE, and inflammatory cytokine assay. The correlation between these markers was investigated and the diagnostic accuracy of peripheral blood eosinophils and total IgE to identify eosinophilic asthma phenotype was calculated using receiver operating characteristics area under the curve (ROC AUC). RESULTS: FeNO was positively correlated with percentage of blood eosinophils (r=0.276, p=0.017) and total blood IgE (r=0.3647; p=0.0013). No relationship between FeNO and serum inflammatory cytokines was detected. AUC of blood eosinophils and total IgE were 57% and 64% at FeNO ≥25 ppb and were 67% and 64% at FeNO >50, respectively. The higher predictive ability was detected at FeNO >50 ppb where the best cutoff point for blood eosinophil % was ≥4.0% (sensitivity 66.7%, specificity 60.0%) and the best cutoff point for total IgE was ≥350 (sensitivity 66.7%, specificity 63.6%). CONCLUSION: In patients with partly controlled asthma, peripheral blood eosinophil and total IgE showed equal useful accuracy in predicting eosinophilic airways. However, higher predictive values were reported at FeNO level >50 ppb. FeNO was positively correlated with peripheral blood eosinophil, total IgE but not with any of the studied cytokines.

Knowledge, Attitude and Practice Regarding Ramadan Fasting and Related Determinants in Patients with Type 2 Diabetes at a Saudi Diabetes Clinic.

OBJECTIVE: This study was carried out in type 2 diabetes mellitus (T2DM) patients to assess their knowledge, attitude and practice about fasting during Ramadan and to identify the sociodemographic determinants of the knowledge, attitude and practice. METHODS: A total of 107 T2DM patients were interviewed at a diabetes clinic in the Eastern Saudi Arabia. A questionnaire containing knowledge, attitude and practice questions about fasting during Ramadan was used to collect data. Data about age, gender, city of residence, nationality, level of education, and history of diabetes in family were also collected. Descriptive and inferential statistics were carried out using IBM-SPSS Version 21. RESULTS: The mean total score for knowledge, attitude and practice was 16.5 ±3.72 (out of 27). The individual scores for knowledge, attitude and practice were: 9.67±2.53 (out of 16), 4.10±1.28 (out of 6), and 2.77±1.08 (out of 5), respectively. Gender (OR: 4.08, 95% CI: 1.05,15.79 and p<0.041), education (OR: 0.068, 95% CI: 0.008,0.594, p<0.015) and family history (OR: 5.086, 95% CI: 1.095, 23.630 p<0.038) were identified as independent determinants of the total score. CONCLUSION: Gender, Family history of diabetes and Education are determinants of knowledge, attitude and practice regarding fasting during Ramadan in the T2DM patients. A significant knowledge practice gap exists that necessitates further strengthening of the Pre-Ramadan education program for T2DM patients.

Variable response to inhaled nitric oxide in postoperative patients of mitral stenosis with pulmonary hypertension.

BACKGROUND: This study was carried out to determine the vasodilator response of inhaled nitric oxide in patients with pulmonary hypertension (PH) after valve replacement surgery for mitral valve disease. METHOD: This Quesi experimental study was carried out at the intensive care unit of Armed Forces Institute of Cardiology (AFIC) in collaboration with Department of Physiology, Army Medical College, Rawalpindi from March 2004 to February 2006. Thirty patients with systolic Pulmonary Artery Pressure (PAP) > 50 mmHg on pre-operative echocardiography were inducted. Swan Ganz catheter was inserted to record baseline pulmonary artery pressure and pulmonary capillary wedge pressure (PCWP), while cardiac output (CO) was recorded through lithium dilution method. Pulmonary Vascular Resistance (PVR) was calculated with the help of a formula. Inhaled nitric oxide (iNO) was administered after the surgery and the same parameters were recorded again after one hour. RESULTS: The majority of patients were females (73%), while males were only 27%. Out of 30, 21 had isolated mitral stenosis and 9 had mixed mitral and aortic valve disease. 22 patients responded significantly to iNO therapy with > or = 40.0% reduction in their baseline PVR while 8 patients showed insignificant improvement in their PVR (663 +/- 233 dynes.sec.cm(-5) to 605 +/- 222 dynes.sec.cm(-5)). CONCLUSION: Significant improvement in pulmonary vascular resistance in the responders and maintenance of high pressures despite iNO therapy in non-responders indicate that apart from some abnormality in nitric oxide pathway, some other factors may be a contributing in the causation of PH secondary to mitral stenosis in adults, which warrant further studies.

Effect of Zamzam water on blood methemoglobin level in young rats.

BACKGROUND: Methemoglobin (MetHb) level in blood indicates exposure to nitrogenous compounds. Acquired methemoglobinemia as a result of exposure to nitrates in drinking water is primarily an issue for infants. The amount of nitrates in Zamzam water is said to be on the high side. This study was designed to determine the effect of prolonged use of Zamzam water on MetHb in rat pups. MATERIALS AND METHODS: Wistar rat pups (n = 52, 3 weeks old) were divided into four equal groups. All of them were given normal laboratory chow. The groups differed only in the exclusive source of water, that is ordinary bottled water, standardized mineral water, old Zamzam water (stored since 2008) or fresh Zamzam water. MetHb level was checked (using Avoximeter 4000) at the baseline, and then every week for 4 weeks from blood obtained from retro-orbital sinus. Other parameters tested were total haemoglobin, oxyhemoglobin and carboxyhemoglobin. ANOVA was used to compare the means between the groups. RESULTS: None of the rats in any of the four groups showed any sign of methemoglobinemia or toxicity. Both groups on Zamzam water showed higher increments in their total hemoglobin by the end of the study compared to their baseline (22%) than the ordinary water (9%) and the mineral water (5%) groups. None of the groups showed any significant difference in MetHb levels on intergroup comparison at any of the weekly readings and at the end of the study. CONCLUSION: Prolonged use of Zamzam water did not induce any significant difference in MetHb concentration in rat pups, which might indicate that it is safe for infants.

Determinants of energy drinks consumption among the students of a Saudi University.

BACKGROUND: Energy drinks contain stimulants mainly caffeine. The use of these drinks by university students is on the rise despite concerns about their safety. This study identified the determinants of the consumption of energy drinks in a cohort of Saudi university students. MATERIALS AND METHODS: This cross-sectional study was carried out at Imam Abdulrahman Bin Faisal University in Saudi Arabia. The students who volunteered to participate (n = 1255) were asked to complete a pretested questionnaire soliciting information on gender, marital status, class and college of study, pattern of energy drinks use, reasons for use, any benefits as well as any untoward effects experienced. Data was analysed using IBM-SPSS (version 21) to determine frequencies and compare various categories of the energy drink users. Logistic regression analysis were performed to identify determinants of energy drinks consumption. RESULTS: Out of 1255 participants, 245 reported using energy drinks. Out of a total 1255 students, 903 (72%) were from medical and 352 (28%) from nonmedical colleges of the university. There were 890 junior and 365 senior students. The female participants were significantly more among both senior and junior medical students. The age of the participants (mean ± SD) was 20.2 ± 1.9 years. The frequency of energy drinks users was higher in the male nonmedical students (both senior and junior) compared to the medical students. The most significant determinants identified were male gender (odds ratio [OR] 4.2, 95% confidence interval [CI] =3.34, 6.12), and being single (OR = 2.8, CI = 1.98, 4.24). In addition, being in non-medical field of study (OR = 1.3, 95% CI=0.61-2.13) was also found to have a reasonable association with energy drink consumption. CONCLUSION: We report male gender, unmarried status, and studying in nonmedical colleges of the university as the main determinants of the consumption of energy drinks by university students. Scrutiny of the patterns and reasons for the consumption of energy drinks might help in developing educational interventions to ensure the appropriate use of energy drinks by young adults.

Biological alterations in renal and hepatic tissues by a novel gold (III) anti-cancerous compound.

OBJECTIVES: Newer organo-metallic, specifically gold (III) complexes with multiple ligands are currently being formulated with primary focus of having increased anti-cancerous properties and decreased cytotoxicity. In this study, histological toxicity profile of a newly formulated anti-cancerous gold (III) compound [trans-(±)-1,2-(DACH)2Au]Cl3 Bis(trans-1,2-Diaminocyclohexane) was investigated by evaluation of kidney and liver tissues of rats treated by the compound. MATERIALS AND METHODS: This is a quasi-experimental study. In acute toxicity component of the study, (n = 16) male rats weighing between 200-250 g were administered single, variable concentration of the gold (III) compound, [trans-(±)-1,2-(DACH)2Au]Cl3 Bis(trans-1,2-Diaminocyclohexane) to determine LD50 (dose that is lethal to 50% of rats). An IP injection of 2.3 mg/kg (equivalent to 1/10 of LD50) was injected for 14 consecutive days to (n=10) male rats in the sub-acute component of the study. Autopsy preservation of liver and kidney tissue in buffered formalin, sample processing, histopathological evaluation, and comparison with unremarkable controls (n=5) was conducted sequentially. RESULTS: A dose of 2.3 mg/kg did not produce any tubular necrosis in kidney specimens. Mild interstitial inflammation with prominence of plasma cells was the main histological alteration. Plasmacytic pyelitis was also seen. Varying extents of cytoplasmic vacuolization and mild focal lobular and portal inflammation were predominant hepatic microscopic findings. CONCLUSION: [trans-(±)-1,2-(DACH)2Au]Cl3 Bis(trans-1,2-Diaminocyclohexane) produced no histological damage in renal and hepatic tissues of rats. This very limited sample animal-based study points to the relative safety of this new gold compound. However, there is a need to compare this compound with established drugs in a comparative non-animal based study.

Frequency and characteristics of skin cancers diagnosed at Ayub Medical College, Abbottabad Pakistan from 1995-2003.

BACKGROUND: Our histopathology laboratory serves mountainous area of Hazara Division in Northern Pakistan. This study is an analysis of the records of skin cancers reported over a nine years period to develop local statistics about frequency and characteristics of skin cancers. METHODS: Data from 1995-2003 record of cancers reported by Department of Pathology, Ayub Medical College, Abbottabad were analysed to calculate cumulative and year wise frequency of skin cancers and their major types. Frequency distribution with reference to gender and age was also calculated. RESULTS: Skin cancers were 220 (1.04%) out of the total 21075 cancers recorded during this period. Squamous cell carcinoma was diagnosed in 118 (53.6%), Basal cell carcinoma in 88 (40%) and Malignant melanoma in 14 (6.4%) cases. The mean age for all skin cancers considered together was 58.75 +/- 15.21. Non Melanoma Skin Cancer (NMSC) were seen in all age groups (minimum 15, maximum 103 years), while no malignant melanoma patient was under 35 years of age. Gender difference in distribution was negligible with slight male preponderance (23:21). Malignant melanoma was significantly (p < 0.05) more in males (71.4%), while distribution of both the types of NMSC was non-significantly in favour of males. We found no significant rise or fall in total skin cancers or any type of skin cancer in this 9 years period. CONCLUSIONS: At present the frequency of skin cancer is stable at around 1% of total cancers reported at Ayub Medical College, reflecting a stable very low incidence rate of skin cancer in Hazara Division of Pakistan.

Effect of Nigella sativa supplementation over a one-year period on lipid levels, blood pressure and heart rate in type-2 diabetic patients receiving oral hypoglycemic agents: nonrandomized clinical trial.

BACKGROUND: Diabetic patients with hypertension and dyslipidemia are at a high risk of cardiovascular complications. OBJECTIVES: To determine the effect of Nigella sativa supplementation on the lipid profile, mean arterial pressure, and heart rate in persons with type 2 diabetes on oral hypoglycemic agents (OHA). DESIGN: Single-blind, nonrandomized. SETTING: Diabetes clinic of a university hospital in Saudi Arabia. PATIENTS AND METHODS: Type-2 diabetic patients were recruited by purposive sampling and assigned to treatment or control at the discretion of the investigator with the patient blinded to treatment. Before the in.tervention and every 3 months thereafter until the end of the treatment period, the following parameters were measured: triglycerides (TG), total cholesterol (TC), low density lipoprotein cholesterol (LDL-C), high density lipoprotein cholesterol (HDL-C), systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP), heart rate (HR), and body mass index (BMI). Results at the baseline and each subsequent visit were compared between the two groups. MAIN OUTCOME MEASURE(S): Lipid and cardiovascular parameters, and BMI. RESULTS: Fifty-seven patients were assigned to receive N sativa 2 g daily for one year and 57 were assigned to receive an identical regimen of placebo, along with OHA. A significant decrease in HDL-C and increase in the TC/HDL-C and LDL-C/HDL-C ratios were seen in the control group. The N sativa group had a signifi.cant decline in TC, LDL-C, TC/HDL-C and LDL-C/HDL-C ratios, compared with the respective baseline data and the control group. HDL-C was significantly elevated in the N sativa group. The control group showed a significant elevation in MAP. The N sativa group had a significant reduction in SBP, DBP, MAP and HR and a significant decrease in DBP, MAP and HR as compared with the control group. CONCLUSION: N sativa supplementation improves total cholesterol, mean arterial pressure and heart rate in type 2 diabetes patients on oral hypoglycemic agents. LIMITATIONS: There were 9 subjects in each group lost to follow up; thus the sample size could not be maintained as per the sample size calculation. The study was nonrandomized and thus there was a possibility of allocation bias. (Clinical trial registration number: CTRI/2013/06/003781, Clinical Trial Registry of India).

Effect of Nigella sativa supplementation on lung function and inflammatory mediatorsin partly controlled asthma: a randomized controlled trial.

BACKGROUND: Nigella sativa and its derivatives have been reported to have anti-inflammatory and bronchodilator effects, but the effects have been evaluated in only a few clinical studies. OBJECTIVES: To determine the effect of N sativa supplementation on inflammation of the airways and limitation of airflow in partly controlled asthma patients. DESIGN: Single-blind, placebo-controlled, randomized study. SETTING: Asthma and allergy clinic of a university hospital in eastern Saudi Arabia. PATIENTS AND METHODS: Patients were divided into three groups. A control group (n=24) received the placebo, while NS-1 and NS-2 groups (n=26 each) received 1 and 2 g/day of N sativa, respectively, for 3 months along with maintenance inhaled therapy. MAIN OUTCOME MEASURE(S): Asthma control test (ACT) score, fractional exhaled nitric oxide (FeNO), peak expiratory flow (PEF) variability and other pulmonary function tests, IgE, serum cytokines, and frequency of exacerbations. RESULTS: FEF25-75% and FEV1 (% predicted) increased significantly (P < .05) at both 6 and 12 weeks in the NS-2 group. PEF variability significantly improved in both NS-1 and NS-2 groups at 6 and 12 weeks as compared with the controls (P < .05). FeNO and serum IgE decreased significantly after 12 weeks in both the NS-1 and NS-2 groups vs baseline (P < .05). Both doses of N sativa produced a significant increase in the serum IFN-gamma at 12 weeks vs baseline (P < .05) as well as a significant improvement in the ACT score at 6 and 12 weeks vs baseline (P < .001, < .01). Significantly fewer patients had exacerbations in the NS-1 group (P < .05). CONCLUSION: N sativa supplementation with inhaled maintenance therapy improves some measures of pulmonary function and inflammation in partly controlled asthma. LIMITATIONS: No bronchoalveolar lavage or sputum samples taken for measurement of asthma markers. ISRCTN registry: ISRCTN48853858 DOI 10.1186/ISRCTN48853858.

Role of Various Potassium Channels in Caffeine-induced Aortic Relaxation in Rats.

BACKGROUND: Studies done on caffeine-induced changes in aortic rings have demonstrated inconclusive results. Moreover, the role of various potassium channels in caffeine-induced effects has not been explored so far. The present in vitro study was designed to explore the direct effects of caffeine on rat aortic rings and the role of various potassium channels in those changes/effects. MATERIALS AND METHODS: This study was carried out in College of Medicine, University of Dammam. Aortic rings obtained from Sprague Dawley rats were mounted in the organ bath. Tension in the aortic rings was measured with an isometric force transducer and recorded with a PowerLab data-acquisition system. Aortic rings in relaxed and contractile state were exposed to caffeine and various potassium channel blockers (glyburide, 4-aminopyridine, or tetraethylammonium). RESULTS: Caffeine produced significant relaxation of isolated aortic rings (baseline tension: 1.26 ± 0.30 g, tension after adding cumulative concentrations of caffeine: 1.12 ± 0.31 g, P < 0.05) in the absence or presence of norepinephrine (NE) (tension induced by NE: 1.06 ± 0.37 g, tension after adding cumulative concentrations of caffeine: 1.01 ± 0.36 g, P < 0.05). Caffeine's vasodilatory effects were, however, blocked in aortic rings pretreated with different types of potassium channel blockers such as 4-aminopyridine (tension induced by NE: 1.52 ± 0.41 g, tension after adding cumulative concentrations of caffeine: 1.50 ± 0.37 g, P > 0.05), glyburide (tension induced by NE: 0.82 ± 0.35 g, tension after adding cumulative concentrations of caffeine: 0.79 ± 0.42 g, P > 0.05), and tetraethylammonium (tension induced by NE: 0.68 ± 0.34 g, tension after adding cumulative concentrations of caffeine: 0.67 ± 0.33 g, P > 0.05). CONCLUSION: Caffeine causes significant dilation of aortic rings, and this vasodilatory effect may involve ATP-dependent, calcium-mediated, or voltage-dependent potassium channels.

Effect of energy drink intake before exercise on indices of physical performance in untrained females.

OBJECTIVES: To determine the effect of energy drink consumption before exercise on indices of physical performance in untrained females. METHODS: This single blind placebo controlled experimental study was carried out at the Physiology Department, University of Dammam, Dammam, Kingdom of Saudi Arabia from September 2011 to May 2012, on 32 healthy female students, in a crossover design. They were given either a standardized energy drink or the placebo 45 minutes before the exercise. Time to exhaustion and the stages of Bruce protocol achieved were noted. Heart rate, blood pressure, peripheral capillary oxygen saturation, and blood lactate were recorded before and after the exercise. Maximum oxygen consumption (VO2max) was calculated by formula. Paired sample t-test was used for statistics. RESULTS: The mean age was 19.93±0.8 years, mean height 156.40±3.83 cm, and the mean weight 51.73±3.65 kg. Time to exhaustion in the placebo group was 11.67±1.51 minutes and 11.41±1.56 in the energy drink group (p less than 0.157). The VO2max in the placebo group was 34.06±6.62, while it was 32.89±6.83 in the energy drink group (p less than 0.154). There were no significant differences between the placebo and the energy drinks groups in regards to heart rate, blood pressure, and blood lactate levels, before or after the exercise. However, there were significant differences before, immediately, and 30 minutes post exercise for all parameters between each group. CONCLUSION: The effects of energy drinks intake on physical performance during the exercise in our small sample does not significantly differ from placebo.

Nigella sativa: A potential natural protective agent against cardiac dysfunction in patients with type 2 diabetes mellitus.

OBJECTIVES: To study the effect of Nigella sativa supplementation on cardiac functions in Type 2 diabetic patients treated with oral hypoglycemic agents. BACKGROUND: Diabetes mellitus is associated with a high risk of cardiovascular morbidity and mortality. A number of reported beneficial effects of N. sativa on cardiovascular function were the inspiration for this study. MATERIALS AND METHODS: Sixty patients with uncontrolled diabetes (hemoglobin A1c [HbA1c] >7%) and with no known cardiovascular complications were recruited from the outpatient diabetes clinic. They were assigned, by convenience, to two groups; the control group received activated charcoal as placebo while the test group received 2 g/day of powdered N. sativa for 1-year. All patients continued with their standard oral hypoglycemic agents. Echocardiography was used to evaluate the diastolic function, systolic function, and left ventricular mass (LVM) before the intervention and after 6 and 12 months of the treatment. RESULTS: HbA1c decreased significantly in the N. sativa group but did not change in the control group. Echocardiographic assessment in the control group showed impairment in diastolic function after 12 months, but there were no significant changes in fractional shortening (FS) or ejection fraction (EF). Furthermore, left ventricular (LV) dimensions at diastole and systole, LVM, and LVM index were significantly increased. In N. sativa group, no significant changes were found in diastolic function or LVM. LV dimension at systole was decreased while FS and EF were significantly increased after 6 and 12 months. CONCLUSION: N. sativa supplementation may protect the hearts of type 2 diabetic patients from diastolic dysfunction while improving LV systolic function.