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81.
Fazile Canturk Muhammet Karaman Christopher P. Selby Michael G. Kemp Gulnihal Kulaksiz-Erkmen Jinchuan Hu Wentao Li Laura A. Lindsey-Boltz Aziz Sancar 《Proceedings of the National Academy of Sciences of the United States of America》2016,113(17):4706-4710
Plants use light for photosynthesis and for various signaling purposes. The UV wavelengths in sunlight also introduce DNA damage in the form of cyclobutane pyrimidine dimers (CPDs) and pyrimidine (6-4) pyrimidone photoproducts [(6-4)PPs] that must be repaired for the survival of the plant. Genome sequencing has revealed the presence of genes for both CPD and (6-4)PP photolyases, as well as genes for nucleotide excision repair in plants, such as Arabidopsis and rice. Plant photolyases have been purified, characterized, and have been shown to play an important role in plant survival. In contrast, even though nucleotide excision repair gene homologs have been found in plants, the mechanism of nucleotide excision repair has not been investigated. Here we used the in vivo excision repair assay developed in our laboratory to demonstrate that Arabidopsis removes CPDs and (6-4)PPs by a dual-incision mechanism that is essentially identical to the mechanism of dual incisions in humans and other eukaryotes, in which oligonucleotides with a mean length of 26–27 nucleotides are removed by incising ∼20 phosphodiester bonds 5′ and 5 phosphodiester bonds 3′ to the photoproduct.Plants and other organisms that depend on photosynthesis are, by necessity, exposed to more sunlight than other organisms that are chemotrophs or heterotrophs. Hence, plants are expected to receive more exposure to UV wavelengths of light than other organisms. The genotoxic effects of UV are somewhat mitigated by the reflection of UV by the waxy leaf surface and absorbance of UV by the intracellular pigments that are present at high concentration in plant cells, including carotenoids and flavonoids. Nevertheless, plants still receive considerable amounts of DNA-damaging UV radiation and therefore must have the means to cope with the damage to ensure their survival. Indeed, DNA sequencing has revealed that plant genomes contain genes that are homologous to the genes of all major DNA repair pathways, including photoreactivation, nucleotide excision repair, base excision repair, and recombination/double-strand break repair (1–6).However, biochemical studies of these DNA repair mechanisms have been limited. Of significance, Arabidopsis photolyases have been expressed in heterologous systems, purified, and characterized (7–9). Similarly, some of the enzymes of the base excision repair and recombination/double-strand break repair systems have been studied. In contrast, there have been no mechanistic studies on plant nucleotide excision repair, although it is known that plants can remove cyclobutane pyrimidine dimers (CPDs) and pyrimidine (6-4) pyrimidone photoproducts [(6-4)PPs] in a photolyase-independent manner (6, 10, 11), presumably by nucleotide excision repair. Here, we have used an Arabidopsis cell line and the in vivo excision assay recently developed in our laboratory (12–14) to demonstrate that Arabidopsis removes these photoproducts by dual incisions in a manner that is virtually identical to human nucleotide excision repair. 相似文献
82.
Reda Elkacmi Otmane Boudouch Aziz Hasib Mustapha Bouzaid Mounir Bennajah 《Sustainable Chemistry and Pharmacy》2020
Over the years, olive mill wastewater (OMW), which is generated from olive oil production has attracted considerable attention as one of the most polluted wastewaters due to its high concentrations of toxic compounds. It is a truism nowadays to guide research towards a novel and efficient technologies in order to treat this hazardous waste.In this paper, detoxification of OMW in an external loop airlift reactor (ALR) by electrocoagulation (EC) powered by photovoltaic solar system as a renewable and sustainable energy source was investigated. The effects of the operating parameters, such as electrolysis time, initial pH, current density (CD), and the axial position of the electrode were studied in continuous flow with two aluminum electrodes. A rate of abatement of about 79.24% for COD, 94.82% for polyphenols and 97.87% for dark color was observed within 40 min of treatment at 32.14 mA/cm2 current density, a position of the electrodes at 35 cm from the bottom of the riser compartment, and initial pH of 5.6. Furthermore, under these optimal conditions, the power supplied by photovoltaic cells led to amount of electrode dissolved (ELC) and specific energy consumption (SEC) of around 0.1118 kg/m3 and 9.86 kWh/m3, respectively. It has been proven that the EC treatment of OMW in ALR coupled with renewable energy source offers a low operation cost (0.2 USD/m3) compared to other treatment processes. 相似文献
83.
Rui Yang Marc Weisshaar Federico Mele Ibtihal Benhsaien Karim Dorgham Jing Han Carys A. Croft Samuele Notarbartolo Jrmie Rosain Paul Bastard Anne Puel Bernhard Fleckenstein Laurie H. Glimcher James P. Di Santo Cindy S. Ma Guy Gorochov Aziz Bousfiha Laurent Abel Stuart G. Tangye Jean-Laurent Casanova Jacinta Bustamante Federica Sallusto 《The Journal of experimental medicine》2021,218(8)
We have described a child suffering from Mendelian susceptibility to mycobacterial disease (MSMD) due to autosomal recessive, complete T-bet deficiency, which impairs IFN-γ production by innate and innate-like adaptive, but not mycobacterial-reactive purely adaptive, lymphocytes. Here, we explore the persistent upper airway inflammation (UAI) and blood eosinophilia of this patient. Unlike wild-type (WT) T-bet, the mutant form of T-bet from this patient did not inhibit the production of Th2 cytokines, including IL-4, IL-5, IL-9, and IL-13, when overexpressed in T helper 2 (Th2) cells. Moreover, Herpesvirus saimiri–immortalized T cells from the patient produced abnormally large amounts of Th2 cytokines, and the patient had markedly high plasma IL-5 and IL-13 concentrations. Finally, the patient’s CD4+ αβ T cells produced most of the Th2 cytokines in response to chronic stimulation, regardless of their antigen specificities, a phenotype reversed by the expression of WT T-bet. T-bet deficiency thus underlies the excessive production of Th2 cytokines, particularly IL-5 and IL-13, by CD4+ αβ T cells, causing blood eosinophilia and UAI. The MSMD of this patient results from defective IFN-γ production by innate and innate-like adaptive lymphocytes, whereas the UAI and eosinophilia result from excessive Th2 cytokine production by adaptive CD4+ αβ T lymphocytes. 相似文献
84.
Malathesh Barikar C. Ibrahim Ferose Aziz Nirisha P. Lakshmi Kumar Channaveerachari Naveen Chand Prabhat Kumar Manjunatha Narayana Math Suresh Bada Thirthalli Jagadisha Manjappa Adarsha Alur Parthasarathy Rajani Reddy Shanivaram Arora Sanjeev 《The Psychiatric quarterly》2021,92(3):843-850
Psychiatric Quarterly - Technology driven capacity building initiatives are the way to break the barrier of shortage of mental health human resources in India. This new path, while is a welcome... 相似文献
85.
Ahmed Aziz Bousfiha Leïla Jeddane Fatima Ailal Waleed Al Herz Mary Ellen Conley Charlotte Cunningham-Rundles Amos Etzioni Alain Fischer Jose Luis Franco Raif S. Geha Lennart Hammarström Shigeaki Nonoyama Hans D. Ochs Chaim M. Roifman Reinhard Seger Mimi L. K. Tang Jennifer M. Puck Helen Chapel Luigi D. Notarangelo Jean-Laurent Casanova 《Journal of clinical immunology》2013,33(6):1078-1087
The number of genetically defined Primary Immunodeficiency Diseases (PID) has increased exponentially, especially in the past decade. The biennial classification published by the IUIS PID expert committee is therefore quickly expanding, providing valuable information regarding the disease-causing genotypes, the immunological anomalies, and the associated clinical features of PIDs. These are grouped in eight, somewhat overlapping, categories of immune dysfunction. However, based on this immunological classification, the diagnosis of a specific PID from the clinician’s observation of an individual clinical and/or immunological phenotype remains difficult, especially for non-PID specialists. The purpose of this work is to suggest a phenotypic classification that forms the basis for diagnostic trees, leading the physician to particular groups of PIDs, starting from clinical features and combining routine immunological investigations along the way. We present 8 colored diagnostic figures that correspond to the 8 PID groups in the IUIS Classification, including all the PIDs cited in the 2011 update of the IUIS classification and most of those reported since. 相似文献
86.
Mohammad Abd Alkhalik Basha Hossam M. Abdelrahman Maha Ibrahime Metwally Nader Ali Alayouty Nesreen Mohey Mohamed M.A. Zaitoun Hosam Nabil Almassry Hala Y. Yousef Ahmed A. El Sammak Sameh Abdelaziz Aly Hesham Youssef Algazzar Mohamed Abd El‐Aziz Mohamed Farag Walid Mosallam Waleed S. Abo Shanab Safaa A. Ibrahim Ekramy A. Mohamed Abd El Motaleb Mohamed Amira Hamed Mohamed Afifi Ola A. Harb Taghreed M. Azmy 《Journal of magnetic resonance imaging : JMRI》2021,53(1):292-304
87.
Mahdi Rajabizadeh Dominique Adriaens Barbara De Kegel Aziz Avci Çetin Ilgaz Anthony Herrel 《Journal of anatomy》2021,238(1):131-145
As body size strongly determines the biology of an organism at all levels, it can be expected that miniaturization comes with substantial structural and functional constraints. Dwarf snakes of the genus Eirenis are derived from big, surface-dwelling ancestors, considered to be similar to those of the sister genus Dolichophis. To better understand the structural implications of miniaturization on the feeding apparatus in Eirenis, the morphology of the cranial musculoskeletal system of Dolichophis schmidti was compared with that of the miniature Eirenis punctatolineatus and E. persicus using high-resolution µCT data. The gape index was compared between D. schmidti and 14 Eirenis species. Our results show a relatively increased neurocranium size and decreased maximal jaw muscle force in E. persicus, compared with the D. schmidti, and an intermediate situation in E. punctatolineatus. A significant negative allometry in gape index relative to body size is observed across the transition from the Dolichophis to Pediophis and Eirenis subgenera. However, the gape index relative to head size showed a significant negative allometry only across the transition from the Dolichophis to Pseudocyclophis subgenus. In Dolichophis–Eirenis dwarfing lineages, different structural patterns are observed through miniaturization, indicating that overcoming the challenge of miniaturization has achieved via different adaptations. 相似文献
88.
Hakim Hashom Mohd Khan Hussein Omar Ismail Siti Afifah Lalung Japareng Kofi Abban Edward Aziz Mohd Yusmaidie Pati Siddhartha Nelson Bryan Raveen Chambers Geoffrey Keith Edinur Hisham Atan 《International journal of legal medicine》2021,135(4):1433-1435
International Journal of Legal Medicine - DNA profiling of X-chromosomal short tandem repeats (X-STR) has exceptional value in criminal investigations, especially for complex kinship and incest... 相似文献
89.
90.
Molecular signalling of a novel curcumin derivative versus Tadalafil in erectile dysfunction 下载免费PDF全文
M. T. Abdel Aziz A. M. Rezq H. M. Atta H. Fouad A. M. Zaahkouk H. H. Ahmed D. Sabry H. M. Yehia 《Andrologia》2015,47(6):616-625
The efficacy of a novel curcumin derivative (NCD) versus tadalafil in erectile signalling was assessed. Ten control male rats and 50 diabetic male rats were used and divided into the following: diabetic (DM), curcumin (CURC), NCD, tadalafil and NCD combined with tadalafil rat groups. Cavernous tissue gene expression of heme oxygenase‐1 (HO‐1), Nrf2, NF‐B and p38, enzyme activities of heme oxygenase (HO) and nitric oxide synthase (NOS), cGMP and intracavernosal pressure (ICP)/mean arterial pressure (MAP) were assessed. Results showed that 12 weeks after induction of diabetes, erectile dysfunction (ED) was confirmed by the significant decrease in ICP/MAP, a significant decrease in cGMP, NOS, HO enzyme activities, a significant decrease in HO‐1 gene and a significant increase in NF‐?β, p38 genes. Administration of all therapeutic interventions led to a significant increase in ICP/MAP, cGMP levels, a significant increase in HO‐1 and NOS enzymes, a significant increase in HO‐1, and Nrf2 gene expression, and a significant decrease in NF‐?β, p38 gene expression. NCD or its combination with tadalafil showed significant superiority and more prolonged duration of action. In conclusion, a tendency was observed that CURC and NCD have high efficacy and more prolonged duration of action in enhancing erectile function. 相似文献