Spectrum of AIDS Defining Opportunistic Infections in a Series of 77 Hospitalised HIV-infected Omani Patients

Objectives: Most of the morbidity and mortality in human immunodeficiency virus/acquired immune deficiency syndrome (HIV/AIDS) result from opportunistic infections (OIs). Although the spectrum of OIs in HIV infected patients from developing countries has been reported, there is a paucity of data on the natural history, pattern of disease, and survival of hospitalised patients with HIV/AIDS, particularly in Arab countries. The aim of this study was to study retrospectively the spectrum and frequency of various OIs in a cohort of hospitalised HIV-infected Omani patients. Methods: Included in the study were 77 HIV-infected Omani patients admitted to a tertiary care teaching hospital in Muscat, Oman, between January 1999 and December 2008. They were diagnosed on their first admission and hence were not on highly active antiretroviral therapy (HAART) at presentation. The frequency of various clinical and laboratory findings and individual OIs were analysed. Results: In total, 45 patients (58%) had one or more AIDS-defining OIs. Pneumocystis jiroveci pneumonia (PCP) was commonest (25%), followed by cryptococcal meningitis (22%), cytomegalovirus (CMV), retinitis (17%), disseminated tuberculosis (15%), and cerebral toxoplasmosis (12.5%). Only one patient with Mycobacterium avium-intracellulare (MAI) was identified and one patient had disseminated visceral leishmaniasis. The majority of patients (77%) had CD4+ counts <200 cells/µL. Ten patients (22%) died during hospital stays, with five deaths (50%) being caused by disseminated CMV infection. Conclusion: A wide spectrum of OIs is seen in hospitalised HIV-infected patients in Oman. P. jiroveci pneumonia and cryptococcal meningitis were the commonest OIs, while disseminated CMV was the commonest cause of death. We hope these results will advance the knowledge of specialists treating HIV in Oman and the Gulf region.

Role of Omeprazole as An Antifungal Agent

The antifungal activity of various concentrations of omeprazole (0.1mg/ml, 0.25mg/ml, 0.5mg/ml, 1mg/ml, 2.5mg/ml, 5mg/ml, 10mg/ml, and 20mg/ml) were studied in different pH media (5 and 7) against Aspergillus niger, and Trichophyton urbrum.The laboratory results showed the inhibitory effect of omeprazole against Aspergillus niger at pH 7 and starting from concentration 10mg/ml, and against Trichophyton urbrum starting from 1mg/ml. While its antifungal activity in a medium with pH 5 was extended to reach the lower concentrations 0.25mg/ml against selected fungi. Accordingly, omeprazole is pH dependent.It seems that omeprazole changed cell membrane potential of selected fungal species which led to depolarization of cell membrane as a result of inhibition of the proton pump mechanism. This made the fungal cell not willing to uptake chemicals needed for living.Keywords: omeprazole, proton pump inhibitor, antifungal agent, Aspergillus niger, and Trichophyton urbrum

A self-sensing and self-heating planar braided composite for smart civil infrastructures reinforcement

Allocating different capabilities to structural elements simultaneously is still challenging. In this study, a field-applicable multifunctional planar braided composite with the abilities of reinforcing, self-sensing and self-heating was developed for the first time. In this route, three commercial fabrics were used, including cotton, cotton/polyamide, and polyester. The fabrics were first chemically treated and then coated with a carbon nanomaterial-based polymeric conductive paste using screen printing with different concentrations and layers. The samples were then covered and sealed with a thermoplastic polyurethane-based polymer to avoid environmental factors effects. Smart planar composites (SPC) were also used as reinforcement for cementitious specimens. The electrical conductivity and joule heating capability of the samples were also evaluated. The microstructure of the SPCs was investigated using various tests. The mechanical and self-sensing performances of the cementitious composite reinforced with different SPCs were assessed using different load patterns. The results showed a heating rate of 0.44 ˚C/s, a joule heating power of 0.7 W/˚C, and a maximum temperature of 44 ˚C which proved the proper heating capability of the cementitious composites reinforced with SPCs. The great correlation between electrical resistivity changes and strain values indicated the high potential of the composite in strain sensing for different applications. The SPCs also improved the post-crack behaviour of the specimen and its flexural strength and failure strain by approximately 50% and 118%, respectively. The outcomes of this study draw a bright horizon in multifunctional braided composite development with different applications in civil infrastructures, which is a crucial step for intelligent cities' advances.This work was partly financed by the Institute for Sustainability and Innovation in Engineering Structures (ISISE) and the R&D Unit of the Centre for Textile Science and Technology (2C2T) founded by the Portuguese Foundation for Science and technology (FCT) under the reference “UIDP/00264/2020”. The first author also acknowledges the support provided by the FCT/PhD individual fellowship with reference of “2021.07596.BD”

Construction of a Small-Scale Vacuum Generation System and Using It as an Educational Device to Demonstrate Features of the Vacuum

We developed a vacuum generation system composed of a reciprocating compressor (3 tons of refrigeration) with an inverted-function that is ready to be hooked flexibly to a gas-tight container to create an evacuated enclosed atmosphere, without strict limitation of the size of that container. The evacuated container (or vacuum chamber) can serve in different purposes such as educational demonstration of the vacuum properties, extraction of perfumes from herbal resources, and preserving food. We tested the device and found it can reach a vacuum level of 26 inches of mercury in an environment with an atmospheric pressure of 28.5 inches of mercury. We compared the performance of our vacuum device to a rotary-vane vacuum pump of ¼ horsepowers and found that the vacuum pump reaches a set test vacuum level of 25 inches of mercury before the compressor. We then demonstrated experimentally some features of the vacuum using the inverted compressor or the vane vacuum pump. These experiments serve some topics in physics for school students as well as two core subjects of mechanical engineering, namely fluid mechanics and thermodynamics