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1.
Saudi J Biol Sci ; 30(11): 103817, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37841665

RESUMEN

Numerous studies have shown that stress in plant cells and organelles with transport electron chains is related to RNA editing. The ATP synthase complex present in mitochondria plays a crucial role in cellular respiration and consists of several subunits. Among them is the b subunit, which is encoded by the mitochondrial atp4 gene. Computing-based analysis of the effects of RNA editing of the Withania somnifera atp4 gene in mitochondria leading to alterations in the b subunit of ATP synthase. Using the CLC Genomic Workbench 3, RNA editing analysis between the control and salt stress conditions was not significantly different. Depending on RNA editing, the tertiary structure model revealed a change in the states of the b subunit, reflecting differences in the central stalk and F1-catalytic domain. The study found that polar edits in the N-terminus of the b subunit allow for efficient H + ion selectivity and introduce a new coiled-coil alpha-helical structure that may help stabilize the complex. The most noteworthy finding of this study was the strong impact of these editing events on the tertiary structure of the b subunit, which has the potential to affect the ATPase activity and indicate that the editing in this subunit aimed to restore the original active protein and not as a response to salt stress.

2.
Saudi J Biol Sci ; 30(3): 103600, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36874202

RESUMEN

Genomic studies not only help researcher not only to identify genomic features in organisms, but also facilitate understanding of evolutionary relationships. Species in the Withania genus have medicinal benefits, and one of them is Withania frutescens, which is used to treat various diseases. This report investigates the nucleotides and genic features of chloroplast genome of Withania frutescens and trying to clarify the evolutionary relationship with Withania sp and family Solanaceae. We found that the total size of Withania frutescens chloroplast genome was 153.771 kb (the smallest chloroplast genome in genus Withania). A large single-copy region (91.285 kb), a small single-copy region (18.373 kb) form the genomic region, and are distinct from each other by a large inverted repeat (22.056 kb). 137 chloroplast genes are found including 4 rRNAs, 38 tRNAs and 83 protein-coding genes. The Withania frutescens chloroplast genome as well as four closest relatives was compared for features such as structure, nucleotide composition, simple sequence repeats (SSRs) and codon bias. Compared to other Withania species, Withania frutescens has unique characteristics. It has the smallest chloroplast genome of any Withania species, isoleucine is the major amino acid, and tryptophan is the minor, In addition, there are no ycf3 and ycf4 genes, fourth, there are only fifteen replicative genes, while in most other species there are more. Using fast minimum evolution and neighbor joining, we have reconstructed the trees to confirm the relationship with other Solanacaea species. The Withania frutescens chloroplast genome is submitted under accession no. ON153173.

3.
Int J Dent ; 2021: 6645279, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33833803

RESUMEN

OBJECTIVES: To assess dentists' practices and barriers towards infant oral healthcare (IOH) and anticipatory guidance (AG) in eastern Saudi Arabia. METHODS: A regional, cross-sectional survey was distributed to 340 (323 general dentists (GPs) and 17 pediatric dentists (PDs)) working in a governmental setting in eastern Saudi Arabia. A 23 close-ended, pilot-tested questionnaire was developed. The questionnaire asked about dentists' IOH and AG practices. A five-point Likert scale question assessed barriers interfering with AG practices. Descriptive and multivariate logistic regressions were used. RESULTS: Participation rate was 98.5% (335/340). Only 18% of GPs indicated performing IOH exams, while 100% of PDs do. About 90% of GPs would see children on a first visit when they are ≥3 years old, whereas 60% of PDs reported seeing one-year-old children. Older practitioners and those performing AG were more likely to perform IOH (OR = 1.8, CI = 1.06-3.1, and OR = 3.84, CI = 1.93-7.65, resp.). The majority of respondents (94%) felt their training did not prepare them to practice AG. "Parents bringing their children for the first time for emergency or existing conditions" was cited by 99% of respondents as a barrier to performing AG. CONCLUSION: Increasing the awareness of GPs and parents about the importance of IOH and AG is crucial in improving children's oral health. Collaboration with pediatricians for early referral of children is equally important in increasing the awareness on prevention principles.

4.
PLoS One ; 14(11): e0224336, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31682609

RESUMEN

The study underpins barcode characterization of insect species collected from Saudi Arabia and explored functional constraints during evolution at the DNA and protein levels to expect the possible mechanisms of protein evolution in insects. Codon structure designated AT-biased insect barcode of the cytochrome C oxidase I (COI). In addition, the predicted 3D structure of COI protein indicated tyrosine in close proximity with the heme ligand, depicted substitution to phenylalanine in two Hymenopteran species. This change resulted in the loss of chemical bonding with the heme ligand. The estimated nucleotide substitution matrices in insect COI barcode generally showed a higher probability of transversion compared with the transition. Computations of codon-by-codon nonsynonymous substitutions in Hymenopteran and Hemipteran species indicated that almost half of the codons are under positive evolution. Nevertheless, codons of COI barcode of Coleoptera, Lepidoptera and Diptera are mostly under purifying selection. The results reinforce that codons in helices 2, 5 and 6 and those in loops 2-3 and 5-6 are mostly conserved and approach strong purifying selection. The overall results argue the possible evolutionary position of Hymenopteran species among those of other insects.


Asunto(s)
Complejo IV de Transporte de Electrones/genética , Evolución Molecular , Himenópteros/genética , Proteínas de Insectos/genética , Sustitución de Aminoácidos , Animales , Código de Barras del ADN Taxonómico , Especiación Genética , Filogenia , Arabia Saudita
5.
Ecotoxicol Environ Saf ; 174: 197-207, 2019 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-30826546

RESUMEN

Cadmium (Cd) is a toxic heavy metal and an abiotic stressor to plants; however, inoculation of endophytic bacteria can raise resistance in plants against Cd, as well as improve plant growth. In the present study, two endophytic bacterial strains were isolated from Solanum nigrum, identified as Serratia sp. IU01 and Enterobacter sp. IU02 by 16S DNA sequencing. Both IU01 and IU02 were tolerant up to 9.0 mM of Cd in culture broth and successive increase in Cd concentration from 0 mM to 9.0 mM, led to an increase in the SOD enzyme activity of the isolates. Both strains were capable of indole-3-acetic acid (IAA) synthesis and phosphate solubilization, detected through gas spectrometry-mass chromatography (GC-MS) and Pikovskaya agar medium respectively. Brassica juncea plants stressed with 0-25 mg/kg Cd showed retardation in all growth attributes, however, inoculation of strain IU01 and IU02 significantly promoted the plant growth attributes as compared to control. Moreover, antioxidant enzymes and metabolites against reactive oxygen species (ROS) including polyphenol oxidase (PPO), peroxidase (POD), catalase (CAT), superoxide dismutase (SOD), alcohol dehydrogenase (ADH), reduced glutathione (GSH), malondialdehyde (MDA), flavonoid and polyphenolic contents were also significantly relieved by inoculation of IU01 and IU02 in plant exposed to different concentration of Cd stress as compared to control plants. Phytohormone production, phosphate solubilization, and/or antioxidative support of IU01 and IU02 might be responsible for growth promotion and Cd resistance in the plant.


Asunto(s)
Antioxidantes/metabolismo , Cadmio/toxicidad , Endófitos/aislamiento & purificación , Enterobacter/aislamiento & purificación , Serratia/aislamiento & purificación , Contaminantes del Suelo/toxicidad , Solanum nigrum/microbiología , Biodegradación Ambiental , Enterobacter/efectos de los fármacos , Planta de la Mostaza/efectos de los fármacos , Planta de la Mostaza/microbiología , Especies Reactivas de Oxígeno , Serratia/efectos de los fármacos
8.
J Family Community Med ; 13(1): 31-4, 2006 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23012100

RESUMEN

BACKGROUND: Impetigo is a common contagious superficial skin infection, most frequently seen in children. OBJECTIVES: To determine the clinical and epidemiological features of impetigo patients seen in the dermatology clinic of King Fahd Hospital of the University (KFHU). METHODS: This is a retrospective study of impetigo patients seen in the dermatology clinic at KFHU, Al-Khobar, Saudi Arabia, during the period January 1990 to December 2001. Data collected from patients' records included demographic features, clinical features, investigations and treatment. Only patients with positive skin culture were included in the study. RESULTS: The total number of patients included in this study was 65 and constituted 0.08% of all the cases presenting with dermatology problems in that period. Males were affected by impetigo more than the females, giving a ratio of 1.7:1. The majority of the cases occurred in children less than 10 years of age, and the bullous form of impetigo was the predominant type. The sites affected by impetigo were mainly the extremities and the face. The highest number of patients was seen during summer and Staphylococcus was the most common causative agent. CONCLUSION: The incidence and prevalence of impetigo in Saudi Arabia is unknown and can be best defined by prospective community-based study. The diagnosis and management of impetigo is best achieved by microbiological cultures and sensitivities laboratory investigations.

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