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101.
Alvarez-Fernández M Halim VA Aprelia M Laoukili J Mohammed S Medema RH 《The Journal of biological chemistry》2011,286(38):33029-33036
102.
Shobha Thangada Keith Alvares Mario Mangino Mohammed I. Usman M.Sambasiva Rao Janardan K. Reddy 《FEBS letters》1989,250(2):205-210
Using the normal adult rat hepatocytes, plated on rat tail collagen-coated dishes and fed a chemically defined medium, we demonstrate here that ciprofibrate at 0.1 mM concentration, increases significantly the mRNA levels of fatty acyl-CoA oxidase, enoyl-CoA hydratase/3-hydroxyacyl-CoA dehydrogenase bifunctional protein, and thiolase (the three enzymes of the β-oxidation system), and causes peroxisome proliferation. Increase in mRNA levels of these genes was evident within 1 h and was maximal 24 h after the addition of ciprofibrate. In hepatocytes cultured in the absence of ciprofibrate, the basal levels of these enzymes were low and further declined with time. Concomitant treatment of hepatocytes with cycloheximide did not inhibit or superinduce the mRNA levels, indicating that this induction may represent a primary (direct) effect of this compound on the expression of these genes and does not apparently involve short-lived repressor protein(s). 相似文献
103.
Nucleotide excision repair is the major pathway for removing damage from DNA. (A)BC excinuclease is the nuclease activity which initiates nucleotide excision repair in Escherichia coli. In this review, we focus on current understanding of the structure-function of the enzyme and the reaction mechanism of the repair pathway. In addition, recent biochemical studies on preferential repair of actively transcribed genes in E. coli are summarized. 相似文献
104.
Hydroxycinnamates including p-coumaric acid, caffeic acid, ferulic acid, sinapic acid, and their esterified/etherified conjugates such as chlorogenic acids
are abundant in cereals, coffee, fruit and vegetables. Studies have shown their potential in the prevention of chronic diseases
such as cardiovascular disease and cancer. The impact of these dietary hydroxycinnamates on health depends on their bioavailability.
In this article, in vivo and in vitro studies pertaining to bioavailability of hydroxycinnamates are reviewed and discussed.
The chemical structures, existing forms, and/or doses of hydroxycinnamates may affect their metabolic fate. Limited studies
suggest that the relative bioavailability of hydroxycinnamates may be in the following order: chlorogenic acid < rosmarinic
acid < caffeic acid < ferulic acid < p-coumaric acid. Bound hydroxycinnamates generally have lower bioavailability than their monomer counterparts. Further pharmacokinetic
and phamacodynamic studies are required to characterize the metabolism of hydroxycinnamates and their potential health impact
in humans. 相似文献
105.
Sadeq K. Alhag Fahd A. Al-Mekhlafi Nael Abutaha Fahd Mohammed Abd Al Galil Muhammad A. Wadaan 《Journal of Asia》2021,24(1):184-189
Plant secondary metabolites have been recently used for the synthesis of different nanoparticles. The present investigation aimed at evaluating the effect of gold (AuNPs) and silver (AgNPs) nanoparticles synthesized using Acalypha fruticosa leaf extracts to control the mosquito Culex pipiens. The A. fruticosa AuNPs and AgNPs spectra displayed their maximum absorption at 550 nm and 440 nm, respectively. The infrared spectra revealed different functional groups related to different chemical compounds. The larval mortality of aqueous leaf extract of A. fruticosa was 499.54 ppm (LC50) and 1734.06 ppm (LC90) after 24 h of treatment. This study revealed that AuNP (LC50, 30.2 and LC90, 104.83 ppm) and AgNP (LC50, 52.86 and LC90, 157.227 ppm) preparations were highly effective compared to the A. fruticosa extract alone and also more affordable, as a smaller amount was required. The present findings show the potential larvicidal effect of the synthesized AuNPs and AgNPs for the control of mosquito-mediated disease transmission. 相似文献
106.
Mohammed K. Al-Sadoon Mohammed Fahad Albeshr Bilal Ahamad Paray Abdul Rahman Al-Mfarij 《Saudi Journal of Biological Sciences》2021,28(1):582-586
Snakebite being medical emergency and known cause for increased mortality needs assessment and treatment on high-priority bases, even in patients of snakebite who appear fine initially. The current retrospective study presents the snake bites in Saudi Arabia from 2015 to 2018 reported by General Administration of Statistics and Information, Ministry of Health, Kingdom of Saudi Arabia. The data presented in the current study, was extracted, analyzed, and reported after getting ethical approval from institutional committee. Totally, 14,679 cases of snakebites were reported during the four-year study period, with a higher prevalence in males (80%) in their productive age. Most patients were within the age group between 25 and 44 followed by 44 to 64 years. The majority of snakebite affected inhabitants were reported from farms of the rural areas, commonly during night hours of spring and summer seasons when snakes are very active. Only 36 (0.24%) patients out of 14,679 were reported dead and 14,643 (99.63%) were discharged after the treatment. Awareness among the general public should be encouraged and early diagnosis and usage of proper snake antivenoms could be life-saving. The delay in appropriate treatment can lead to significant morbidity and mortality. 相似文献
107.
Mohammed Rafi Shaik Rabbani Syed Syed Farooq Adil Mufsir Kuniyil Mujeeb Khan Mohammed S. Alqahtani Jilani P. Shaik Mohammed Rafiq H. Siddiqui Abdulrahman Al-Warthan Mohammed A.F. Sharaf Abdelatty Abdelgawad Emad Mahrous Awwad 《Saudi Journal of Biological Sciences》2021,28(2):1196-1202
Due to their inexpensive and eco-friendly nature, and existence of manganese in various oxidation states and their natural abundance have attained significant attention for the formation of Mn3O4 nanoparticles (Mn3O4 NPs). Herein, we report the preparation of Mn3O4 nanoparticles using manganese nitrate as a precursor material by utilization of a precipitation technique. The as-prepared Mn3O4 nanoparticles (Mn3O4 NPs) were characterized by using X-ray powder diffraction (XRD), UV–Visible spectroscopy (UV–Vis), High-Resolution Transmission electron microscopy (HRTEM), Field emission scanning electron microscopy (FESEM), Thermal gravimetric analysis (TGA) and Fourier-transform infrared spectroscopy (FT-IR). The antimicrobial properties of the as-synthesized Mn3O4 nanoparticles were investigated against numerous bacterial and fungal strains including S. aureus, E. coli, B. subtilis, P. aeruginosa, A. flavus and C. albicans. The Mn3O4 NPs inhibited the growth of S. aureus with a minimum inhibitory concentration (MIC) of 40 μg/ml and C. albicans with a MIC of 15 μg/ml. Furthermore, the Mn3O4 NPs anti-cancer activity was examined using MTT essay against A549 lung and MCF-7 breast cancer cell lines. The Mn3O4 NPs revealed significant activity against the examined cancer cell lines A549 and MCF-7. The IC50 values of Mn3O4 NPs with A549 cell line was found at concentration of 98 µg/mL and MCF-7 cell line was found at concentration of 25 µg/mL. 相似文献
108.
ABSTRACT: BACKGROUND: Land plants have evolved several measures to maintain their life against abiotic stresses. The accumulation of proline is the most generalized response of plants under drought, heat or salt stress conditions. It is known as an osmoprotectant which also acts as an instant source of energy during drought recovery process. But, both its role and genetic inheritance are poorly understood in agriculture crops. In the present work, advanced backcross quantitative trait locus (AB-QTL) analysis was performed to elucidate genetic mechanisms controlling proline accumulation and leaf wilting in barley under drought stress conditions. RESULTS: The analysis revealed eight QTL associated to proline content (PC) and leaf wilting (WS). QTL for PC were localized on chromosome 3 H, 4 H, 5 H and 6 H. The strongest QTL effect QPC.S42.5 H was detected on chromosome 5 H where drought inducible exotic allele was associated to increase PC by 54%. QTL effects QPC.S42.3 H, QPC.S42.4 H and QPC.S42.6 H were responsible to heighten PC due to the preeminence of elite alleles over the exotic alleles which ranged from 26% to 43%. For WS, QTL have been localized on chromosome 1 H, 2 H, 3 H and 4 H. Among these, QWS.S42.1 H and QWS.S42.4 H were associated to decrease in WS due to the introgression of exotic alleles. In addition, two digenic epistatic interaction effects were detected for WS where the additive effect of exotic alleles imparted a favorable increase in the trait value. CONCLUSIONS: The present data represents a first report on whole-genome mapping of proline accumulation and leaf wilting in barley. The detected QTL are linked to new alleles from both cultivated and wild accessions which bring out an initial insight on the genetic inheritance of PC and WS. These QTL alleles are fixed in the isogenic background of Scarlett, which will allow for positional cloning of underlying genes and to develop drought resilient barley cultivars. 相似文献
109.
Iman O. Sherif Azza Abdel‐Aziz Osama M. Sarhan 《Journal of biochemical and molecular toxicology》2014,28(11):515-521
In the present study, the effect of arjunolic acid on testicular damage induced by intraperitoneal injection of rats with 7 mg/kg cisplatin was studied. Cisplatin induced a significant reduction in testicular weights, plasma testosterone, and testicular reduced glutathione levels in addition to a significant elevation of testicular malondialdehyde levels and testicular gene expressions of inducible nitric oxide synthase (iNOS), tumor necrosis factor‐α (TNF‐α), and p38 mitogen‐activated protein kinase (MAPK) when compared with the control group (p < 0.05). Lower tubular diameters and depletion of germ cells and irregular small seminiferous tubules with Sertoli cells only were observed in the cisplatin group. Arjunolic acid administration significantly corrected the changes in both biochemical and histopathological parameters. Arjunolic acid plays a significant protective role against cisplatin‐induced testicular injury by attenuating oxidative stress parameters along with downregulation of iNOS, TNF‐α, and p38‐MAPK testicular expressions. 相似文献
110.
Jun-Wen Qiao∗ Xiao-Ou Su∗ Yu-Xing Li Jian-Min Yang Yi-Qin Wang Mohammed Kouadir 《Animal biotechnology》2013,24(3):151-155
The 37-kDa laminin receptor precursor/67-kDa laminin receptor (LRP/LR, also known as ribosomal protein SA, RPSA) has been reported to be involved in cancer development and prion internalization. Previous studies have shown that the LRP/LR is expressed in a wide variety of tissues. In particular, expression of LRP/LR mRNA may be closely related to the degree of PrPSc propagation. This study presents a detailed investigation of the LRP/LR mRNA expression levels in eleven normal ovine tissues. Using real-time quantitative PCR, the highest LRP/LR expression was found in neocortex (p < 0.05). Slightly lower levels were found in the heart and obex. Intermediate levels were seen in hippocampus, cerebellum, spleen, thalamus, mesenteric lymph node, and the lowest levels were present in liver, kidney, and lung. In general, the LRP/LR mRNA levels were much higher in neuronal tissues than in peripheral tissues. The observation that differences in LRP/LR mRNA expression levels are consistent with the corresponding variation in PrPSc accumulation suggests that the 37-kDa/67-kDa laminin receptor may be involved in the regulation of PrPSc propagation. 相似文献