Dengue is one of the highest and rapidly spreading vector-borne viral diseases with high mortality rates. The infection causes acute febrile illness, a major public health concern in the tropics and subtropics globally. The disease is caused by an RNA virus that belongs to the Flaviviridae family. The virus is transferred to humans by the mosquito vector called Aedvrves aegypti, which is the cause of new prevalent sicknesses worldwide. These vector-borne viral diseases spread very fast and pose public health and economic challenges that deemed various prevention and control techniques. The Flavivirus genus consists of five different types of viruses starting from DENV-1 to DENV-5. Thus, the present review focuses on the origin of the virus, how the Dengue virus can be detected, infection, the morphology of the virus, its classifications as proposed by ICTV, the replication and genome of the dengue virus, translation, receptor binding, and some vaccine trial volunteers. In addition, it highlights the current challenges and limitations of effective dengue treatment.
Dromedary camels are the natural reservoirs of the Middle East respiratory syndrome coronavirus (MERS-CoV). Camels are mostly bred in East African countries then exported into Africa and Middle East for consumption. To understand the distribution of MERS-CoV among camels in North Africa and the Middle East, we conducted surveillance in Egypt, Senegal, Tunisia, Uganda, Jordan, Saudi Arabia, and Iraq. We also performed longitudinal studies of three camel herds in Egypt and Jordan to elucidate MERS-CoV infection and transmission. Between 2016 and 2018, a total of 4027 nasal swabs and 3267 serum samples were collected from all countries. Real- time PCR revealed that MERS-CoV RNA was detected in nasal swab samples from Egypt, Senegal, Tunisia, and Saudi Arabia. Microneutralization assay showed that antibodies were detected in all countries. Positive PCR samples were partially sequenced, and a phylogenetic tree was built. The tree suggested that all sequences are of clade C and sequences from camels in Egypt formed a separate group from previously published sequences. Longitudinal studies showed high seroprevalence in adult camels. These results indicate the widespread distribution of the virus in camels. A systematic active surveillance and longitudinal studies for MERS-CoV are needed to understand the epidemiology of the disease and dynamics of viral infection.
Alzheimer’s disease (AD) is a common neurodegenerative disorder that presents a significant health concern, often leading to substantial cognitive decline among older adults. A prominent feature of AD is progressive dementia, which eventually disrupts daily functioning and the ability to live independently. A major challenge in addressing AD is its prolonged pre-symptomatic phase, which makes early detection difficult. Moreover, the disease’s complexity and the inefficiency of current diagnostic methods impede the development of targeted therapies. Therefore, there is an urgent need to enhance diagnostic methodologies for detection and treating AD even before clinical symptoms appear. Exosomes are nanoscale biovesicles secreted by cells, including nerve cells, into biofluids. These exosomes play essential roles in the central nervous system (CNS) by facilitating neuronal communication and thus influencing major physiological and pathological processes. Exosomal cargo, particularly microRNAs (miRNAs), are critical mediators in this cellular communication, and their dysregulation affects various pathological pathways related to neurodegenerative diseases, including AD. This review discusses the significant roles of exosomal miRNAs in the pathological mechanisms related to AD, focusing on the promising use of exosomal miRNAs as diagnostic biomarkers and targeted therapeutic interventions for this devastating disease.
9 March 2023 in Saudi Journal of Biological Sciences
Calotropis procera (C. procera) was evaluated as a pharmaceutically useful plant and for its therapeutic effects in the most significant studies. Uzarigenin and Calotropagenin are significant components of this plant that have pharmacological effects on certain systems, including the digestive, immunological, and focal, and peripheral sensory systems. In this study, pathway genes are extracted from high throughput data acc.no. SRR1554320. Seven critical enzymes are involved in studying the effects of sunlight on the formation of Uzaragenin and Calotropagenin in C. procera before and after irrigation. Molecular identification and NCBI submission of six enzyme genes were successful; HSD (acc.no. OQ091761) for 3β-hydroxystroid dehydrogenase, OR (acc.no. OQ091762) for 5beta-pregnan oxidoreductase, MO (acc.no. OQ091763) for Pregnan monooxygenase, HOX (acc.no. OQ091764) for Steroid hydroxylase, MAT (acc.no. OQ091765) for Melonyletransferase, UHOX (acc.no. OQ091766) for Uzarigenin hydroxylase. During dawn after irrigation, the Uzargenin pathway showed the highest activity, however midday after irrigation was the lowest. The most period that showed high activity for the Uzargenin pathway was dawn after irrigation, however, midday after irrigation was the lowest. This data is confirmed by chromatography analysis (UPLC) to calculate the accumulation of Uzarigenin and Calotropagenin in different periods.
5 March 2022 in Saudi Journal of Biological Sciences
The major reports on Calotropis procera (C. procera) indicated the importance of this plant as a resource of pharmaceutically active ingredients as well as its medical advantages. β-amyrin (BA) is a significant substance in this plant and has a pharmacological effects in some frameworks, like focal and fringe sensory system, digestive and immune systems. In this study, the impact of sunlight before and after irrigation on the BA production in C. procera is studied its pathway with involved eight key enzymes. The eight enzymes' genes were characterized and successfully submitted to NCBI; AAS (acc.no. KU997645) for α-amyrin synthase, BAS (acc.no. MW976955) for β-amyrin synthase, SE (acc.no. MW976956) for squalene epoxidase, SS (acc.no. MW976957) for squalene synthase, GPPS, (acc.no. MW976958) for geranyl pyrophosphate synthase, FPPS (acc.no. MW976959) for farnasyl pyrophosphate synthase, CAS1, (acc.no. MZ00598) for cycloartenol synthase1 and LS (acc.no. MZ005982) for lupeol synthase. qRT-PCR analysis revealed high expression levels of GPPS, FPPS, SS, SE, and BAS genes at all times specially midday. Otherwise, CAS1, LS and BAS expression levels were very low at all daylight periods. The UPLC β-amyrin data are in accordance with qRT-PCR results. This indicates that triterpenes biosynthetic pathway in C. procera is going to β-amyrin accumulation with the highest level at midday.
It was found that there was a group of patients with repaired cleft palate who demonstrated a discrepancy between aerodynamic assessment of velopharyngeal (VP) adequacy and clinical judgement of nasal resonance. The aim of this work is to study such group of patients in order to understand and explain this discre-pancy.This study comprised 37 subjects divided into two groups. The first group comprised 12 patients with the diagnosis of repaired overt or submu-cus cleft palate with an age range of 5 to 25 years (mean age = 13 years). This group showed an audible degree of hypernasality in their speech while they have adequate VP port area by aerodynamic measures. The second group (n = 25) comprised age and sex matched normal subjects who demonstrated normal resonance of speech. All the subjects were assessed subjectively for the degree of open nasality on a 4-point scale and objectively by acoustic and aerodynamic studies. Acoustic studies demonstrated a highly significant difference in the nasalance scores between both groups. Aerodynamic studies demonstrated a statistically non-significant difference concerning nasal flow and intra-oral and nasal pressure findings between both groups. While, on the other hand, the timing of both the nasal flow and the intra-oral pressure showed highly significant difference between both groups. Also, the nasal flow peak show a highly significant shift to the right with delay in flow in relation to the intra-oral pressure.