Evaluation of Guinea pig models of the acute phase of allergic rhinitis

Allergic rhinitis is an allergen-IgE complex mediated inflammation of the nasal mucosa characterized by the symptoms of sneezing, nasal itchiness, rhinorrhea, and nasal congestion. The economical and social impact of allergic rhinitis is substantial. The effectiveness of currently available medications is limited. Investigation of more effective medications with fewer side effects is essential. Therefore, this study was intended to establish a model of allergic rhinitis in guinea pigs that can be utilized for further investigation of new medications. Furthermore, this study was also aimed to systematically evaluate the role of some inflammatory mediators of acute allergic reactions in guinea pigs in vivo. Male Dunkin Hartley guinea pigs were intranasally sensitized to, and challenged with, ovalbumin. Sneezing (SN) and nose rubbing (NR) were evaluated on day 21 post initiation of sensitization dose. From day 23 after first sensitization, the animals were anaesthetized with intraperitoneal pentobarbital (30-35mg/kg). The trachea was cannulated in both directions, caudally for measurement of nasal airway pressure (NAP) using a ventilator flow method (8ml/beat, 72beats/min) and rostrally for measurement of lung inflation pressure (LIP). Drugs were administered prior to ovalbumin challenge. SN and NR were evaluated for 30 minutes and NAP was evaluated within 30 minutes post challenge. Cellular infiltration (CI) was assessed from nasal lavage collected 60 minutes post challenge. Sensitized guinea pigs produced symptoms of SN, NR and nasal blockade (NB) in addition to eosinophil infiltration following ovalbumin challenge. A first generation H1 antihistamine, mepyramine, inhibited SN only, whereas later H1 antihistamine, cetirizine, inhibited SN, NR and NB. Montelukast, a leukotriene D4 receptor antagonist, and heparin prevented NB and CI. L-NAME , a non specific nitric oxide synthase inhibitor, inhibited NB and stimulated neutrophil infiltration. In non-sensitized guinea pigs, histamine and acetylcholine introduced intravenously caused dose-dependent decreases in NAP (by the action of histamine on H1 , M2 and perhaps M5 receptors, and acetylcholine on Ml receptors) and increases in LIP (by the action of histamine on H1 receptors, and acetylcholine on Ml receptors). In conclusion pathophysiological changes due to allergic rhinitis in guinea pigs resemble to some extent those in humans. The models reported here reflect the effectiveness of some drugs currently used to treat allergic rhinitis. The models can be used in investigating new potential drugs for the treatment of allergic rhinitis.Medicine, Faculty ofAnesthesiology, Pharmacology and Therapeutics, Department ofGraduat

Education, Youth and Employment in Oman

Aiming at providing support for youth integration into the labor market, Y is one of the first companies that have been created to strive for the participation of young people in social life in Oman. Through the description of its audience, its pedagogic programs and the relations between education and the different professional sectors of activity in Oman, this article examines the tensions and contemporary challenges that reside in “becoming an adult” in Oman

Education, Youth and Employment in Oman

Aiming at providing support for youth integration into the labor market, Y is one of the first companies that have been created to strive for the participation of young people in social life in Oman. Through the description of its audience, its pedagogic programs and the relations between education and the different professional sectors of activity in Oman, this article examines the tensions and contemporary challenges that reside in “becoming an adult” in Oman

Water Metering Pilot Project: A Case Study of Water Demand Management in the Sultanate of Oman

The Sultanate of Oman is experiencing increased pressure on its groundwater resources. This is mainly due to agricultural enterprises, which consume about 92 % of national water resources, as well as an upsurge in industrial, commercial and domestic water use. The ever-growing population, diversification of economic activities and the ensuing rise in national prosperity have meant an increasing demand for water. This has resulted in a marked depletion of groundwater supplies, intrusion of seawater, and deterioration of ground water quality in the case of the Al Batinah region. A scientific and effective water demand management strategy for the Sultanate is therefore needed. Accordingly, the Ministry of Regional Municipalities, Environment and Water Resources (MRMEWR) have conducted several studies related to water demand management in the agricultural, industrial and domestic sectors. One of these studies was the Water Metering Pilot Project (WMPP), initiated in 1994 with the objective of evaluating patterns of water use on a number of randomly selected farms in the southern Al-Batinah. The results obtained over a period of seven years confirm that water metering alone does not help reduce the quantity pumped. These findings have encouraged other advanced studies on water demand management in industrial, commercial, domestic and agriculture sectors in different areas of the Sultanate.

Water Metering Pilot Project: A Case Study of Water Demand Management in the Sultanate of Oman

The Sultanate of Oman is experiencing increased pressure on its groundwater resources. This is mainly due to agricultural enterprises, which consume about 92 % of national water resources, as well as an upsurge in industrial, commercial and domestic water use. The ever-growing population, diversification of economic activities and the ensuing rise in national prosperity have meant an increasing demand for water. This has resulted in a marked depletion of groundwater supplies, intrusion of seawater, and deterioration of ground water quality in the case of the Al Batinah region. A scientific and effective water demand management strategy for the Sultanate is therefore needed. Accordingly, the Ministry of Regional Municipalities, Environment and Water Resources (MRMEWR) have conducted several studies related to water demand management in the agricultural, industrial and domestic sectors. One of these studies was the Water Metering Pilot Project (WMPP), initiated in 1994 with the objective of evaluating patterns of water use on a number of randomly selected farms in the southern Al-Batinah. The results obtained over a period of seven years confirm that water metering alone does not help reduce the quantity pumped. These findings have encouraged other advanced studies on water demand management in industrial, commercial, domestic and agriculture sectors in different areas of the Sultanate.

Wind-powered electric water-pumping system installed in a remote location

In December 1996, the country's first wind-powered, electric water-pumping system was successfully installed at the Ministry of Water Resources (MWR) Heelat Ar Rakah Camp, a remote location some 900 kilometres south of Muscat, the capital city of Oman. A weather-monitoring station comprising temperature, wind speed/direction, humidity and barometric pressure equipment was also installed to investigate the relationship between weather conditions and power output. Both systems are still in operation and are providing valuable data for analysis. This paper investigates the pump's output at different wind speeds and monthly water output against average wind velocity and compares the results with the design output values provided by the system manufacturer. Problems encountered in meeting the irrigation requirements at the camp during periods of low wind are discussed and solutions proposed. The potential of utilizing surplus energy generated during periods of high wind is under investigation. The paper concludes by assessing and analysing the role of wind power amongst other renewable energy sources, in the abstraction and desalination of groundwater supplies.Desalination Irrigation Oman Pump Turbine Wind velocity

Desalination by solar-powered reverse osmosis in a remote area of the Sultanate of Oman

The Ministry of Water Resources successfully conducted an experimental study on the use of solar power to desalinate brackish ground water at their Heelat ar Rakah camp, a remote location some 900 km south of Muscat, the capital of Oman. The system comprises components for pre-treatment of pumped well water to separate hydrogen sulphide, acid dosing to correct the pH, cartridge filtration, a solar powered reverse osmosis unit, and a reject-water evaporation pond. The solar powered system comprises a 23.2 m2 solar photovoltaic generator with a peak capacity of 3250 Wp, a boost charge battery of 200 Ah at 48 VDC, a charge controller, a sine-wave inverter of 3000 VA with an output of 230 V, 50 Hz, and necessary controls and instrumentation. The design water output of 5 m3/day during 5 h (of each day) was achieved, with the output sometimes exceeding 7.5 m3/day. The average cost of production is estimated at US$6.52/m3 over the 20-year lifetime of the equipment. The study has demonstrated that solar-powered reverse osmosis systems are particularly appropriate to remote locations that have limited or no access to supply services such as fuel, power or potable water.Solar power Photovoltaic Desalination Reverse osmosis Brackish water Oman Nejd

Tenofovir-induced Leukocytoclastic Vasculitis

Tenofovir, a nucleotide analog, is one of the first-line medications recommended for the treatment of active chronic hepatitis B virus infection (CHB) and as a primary prophylaxis to prevent hepatitis B reactivation in cases of immunosuppression. We report the first case of tenofovir-induced leukocytoclastic vasculitis (LCV). A 43-year-old obese woman, who was known to have inactive CHB, was diagnosed with chronic immune thrombocytopenic purpura (ITP). She was treated with corticosteroid therapy and was put on tenofovir to prevent hepatitis B virus reactivation. A month later, she developed a skin rash, described as non-blanchable well-defined erythematous to violaceous papules and targetoid patches in her lower extremities. A skin biopsy showed features of LCV. The rash resolved completely within few days after replacing tenofovir with entecavir

Potentially Harmful Drug–Drug Interactions and Their Associated Factors Among Hospitalized Cardiac Patients: A Cross-Sectional Study

Abstract Background Cardiovascular diseases are responsible for a significant proportion of mortalities worldwide. Elderly patients are the most affected by cardiovascular diseases, and because of factors such as polypharmacy, multimorbidity, and age-related changes in drug availability and metabolism, they are highly susceptible to the occurrence of drug–drug interactions. Drug–drug interactions are among the many drug-related problems leading to negative outcomes among inpatients and outpatients. Thus, it is important to investigate the prevalence, involved drugs, and factors related to potential drug–drug interactions (pDDIs) to properly optimize pharmacotherapy regimens for these patients. Objective We aimed to determine the prevalence of pDDIs, drugs most frequently implicated, and significant predictors associated with these interactions among hospitalized patients in the Cardiology Unit at Sultan Qaboos University Hospital in Muscat, Oman. Methods This retrospective cross-sectional study included 215 patients. Micromedex Drug-Reax® was used to identify pDDIs. Data extracted from patients’ medical records were collected and analyzed. Univariable and multivariable linear regression was applied to determine the predictors associated with the observed pDDIs. Results A total of 2057 pDDIs were identified, with a median of nine (5–12) pDDIs per patient. Patients with at least one pDDI accounted for 97.2% of all the included patients. The majority of pDDIs were of major severity (52.6%), fair level of documentation (45.5%), and pharmacodynamic basis (55.9%). Potential drug–drug interactions between atorvastatin and clopidogrel were the most frequently observed (9%). Of all the detected pDDIs, around 79.6% of them included at least one antiplatelet drug. Having diabetes mellitus as a comorbidity (B = 2.564, p < 0.001) and the number of drugs taken during the hospitalization period (B = 0.562, p < 0.001) were factors positively associated with the frequency of pDDIs. Conclusions Potential drug–drug interactions were highly prevalent among hospitalized cardiac patients at Sultan Qaboos University Hospital, Muscat, Oman. Patients having diabetes as a comorbidity and with a high number of administered drugs were at a higher risk of an increased number of pDDIs