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1.
Int J Biochem Mol Biol ; 15(3): 60-67, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39021868

RESUMEN

OBJECTIVES: The current study aimed to correlate OCT1 (organic cation transporter 1) polymorphisms with metformin response variability in Iraqi women with PCOS (polycystic ovarian syndrome) and determine the impact of OCT1 polymorphism. PCOS, an endocrine metabolic disorder, can seriously impact female health including infertility. Although its cause is unclear, it is usually known to be associated with hormonal imbalances. OCT1 is essential for metformin absorption in the liver. Recent research shown that OCT1 polymorphisms affects metformin responsiveness. METHODS: In the present work, a prospective case-control study was conducted at Department of Infertility, Karbala Teaching Hospital for Obstetrics and Gynecology. 100 PCOS patients and 50 healthy controls aged 20-40 were enrolled. Consultant gynecologist diagnosed PCOS patients using Rotterdam criteria and recommended metformin 500 mg twice daily for 3 months. At the start of the trial and after 3 months, all patients and healthy controls underwent hormonal, biochemical and genetic tests. RESULTS: The similar allelic frequencies of OCT1 polymorphism in PCOS and control groups was observed. Most patients with reference wild type alleles (C) showed considerable hormonal and metabolic responses to metformin, while those with mutant alleles (T) showed non-significant responses. CONCLUSION: FSH, prolactin and testosterone hormonal levels may be considered as candidate biomarkers for PCOS detection and metformin related biomedical respond.

2.
Sci Rep ; 14(1): 10297, 2024 05 04.
Artículo en Inglés | MEDLINE | ID: mdl-38704475

RESUMEN

The ideal vaccines for combating diseases that may emerge in the future require more than simply inactivating a few pathogenic strains. This study aims to provide a peptide-based multi-epitope vaccine effective against various severe acute respiratory syndrome coronavirus 2 strains. To design the vaccine, a library of peptides from the spike, nucleocapsid, membrane, and envelope structural proteins of various strains was prepared. Then, the final vaccine structure was optimized using the fully protected epitopes and the fynomer scaffold. Using bioinformatics tools, the antigenicity, allergenicity, toxicity, physicochemical properties, population coverage, and secondary and three-dimensional structures of the vaccine candidate were evaluated. The bioinformatic analyses confirmed the high quality of the vaccine. According to further investigations, this structure is similar to native protein and there is a stable and strong interaction between vaccine and receptors. Based on molecular dynamics simulation, structural compactness and stability in binding were also observed. In addition, the immune simulation showed that the vaccine can stimulate immune responses similar to real conditions. Finally, codon optimization and in silico cloning confirmed efficient expression in Escherichia coli. In conclusion, the fynomer-based vaccine can be considered as a new style in designing and updating vaccines to protect against coronavirus disease.


Asunto(s)
Vacunas contra la COVID-19 , COVID-19 , Biología Computacional , Simulación de Dinámica Molecular , SARS-CoV-2 , SARS-CoV-2/inmunología , SARS-CoV-2/genética , Vacunas contra la COVID-19/inmunología , Humanos , Biología Computacional/métodos , COVID-19/prevención & control , COVID-19/inmunología , COVID-19/virología , Epítopos/inmunología , Epítopos/química , Glicoproteína de la Espiga del Coronavirus/inmunología , Glicoproteína de la Espiga del Coronavirus/genética , Glicoproteína de la Espiga del Coronavirus/química , Inmunoinformática
3.
J Int Med Res ; 51(9): 3000605231196837, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37702549

RESUMEN

OBJECTIVE: To identify the effects of metformin and kisspeptin structural polymorphism on the risk of polycystic ovary syndrome (PCOS) in Iraqi women. METHODS: Samples were collected at the family planning center of Al-Hassan Teaching Hospital (infertility clinic), Iraq. Hormonal and hematological parameters were measured. Kisspeptin structural polymorphisms were analyzed by polymerase chain reaction using a conventional thermal cycler and Phyre2 predictions. Kisspeptin concentrations were assessed by an enzyme-linked immunosorbent assay. RESULTS: Follicle-stimulating hormone (FSH) was the only sex hormone that changed in women with PCOS after metformin treatment. FSH concentrations were significantly increased after therapy compared with before therapy (9.39 ± 2.1 vs 5.13 ± 1.53 IU/L). We found that a single nucleotide polymorphism substituting G to C was related to PCOS. The kisspeptin structural polymorphism showed that the C allele was related to low FSH concentrations after treatment (6.92 ± 2.2 IU/L to 5.34 ± 1.58 IU/L). Kisspeptin concentrations were significantly lower after metformin treatment than before metformin treatment (395.44 ± 67.83 vs 273.18 ± 42.98 ng/mL). CONCLUSION: A variation in the KISS1 gene or its protein structure may be involved in the development of PCOS. The response to metformin may be used as an indicator and could contribute to the early diagnosis and medical therapy of PCOS.


Asunto(s)
Metformina , Síndrome del Ovario Poliquístico , Humanos , Femenino , Kisspeptinas , Irak , Síndrome del Ovario Poliquístico/tratamiento farmacológico , Síndrome del Ovario Poliquístico/genética , Hormona Folículo Estimulante Humana , Polimorfismo de Nucleótido Simple/genética , Metformina/uso terapéutico
4.
Biol Res ; 55(1): 32, 2022 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-36274167

RESUMEN

BACKGROUND: Designed mimetic molecules are attractive tools in biopharmaceuticals and synthetic biology. They require mass and functional production for the assessment of upcoming challenges in the near future. The DARPin family is considered a mimetic pharmaceutical peptide group with high affinity binding to specific targets. DARPin G3 is designed to bind to the HER2 (human epidermal growth factor receptor 2) tyrosine kinase receptor. Overexpression of HER2 is common in some cancers, including breast cancer, and can be used as a prognostic and predictive tool for cancer. The chloroplasts are cost-effective alternatives, equal to, and sometimes better than, bacterial, yeast, or mammalian expression systems. This research examined the possibility of the production of the first antibody mimetic, DARPin G3, in tobacco chloroplasts for HER2 imaging in oncology. RESULTS: The chloroplast specific DARPin G3 expression cassette was constructed and transformed into N. tabacum chloroplasts. PCR and Southern blot analysis confirmed integration of transgenes as well as chloroplastic and cellular homoplasmy. The Western blot analysis and ELISA confirmed the production of DARPin G3 at the commercial scale and high dose with the rate of 20.2% in leaf TSP and 33.7% in chloroplast TSP. The functional analysis by ELISA confirmed the binding of IMAC purified chloroplast-made DARPin G3 to the extracellular domain of the HER2 receptor with highly effective picomolar affinities. The carcinoma cellular studies by flow cytometry and immunofluorescence microscopy confirmed the correct functioning by the specific binding of the chloroplast-made DARPin G3 to the HER2 receptor on the surface of HER2-positive cancer cell lines. CONCLUSION: The efficient functional bioactive production of DARPin G3 in chloroplasts led us to introduce plant chloroplasts as the site of efficient production of the first antibody mimetic molecules. This report, as the first case of the cost-effective production of mimetic molecules, enables researchers in pharmaceuticals, synthetic biology, and bio-molecular engineering to develop tool boxes by producing new molecular substitutes for diverse purposes.


Asunto(s)
Productos Biológicos , Proteínas de Repetición de Anquirina Diseñadas , Animales , Humanos , Línea Celular Tumoral , Receptor ErbB-2 , Cloroplastos/química , Cloroplastos/metabolismo , Preparaciones Farmacéuticas/metabolismo , Mamíferos/metabolismo
5.
Biol. Res ; 55: 32-32, 2022. ilus, graf
Artículo en Inglés | LILACS | ID: biblio-1403570

RESUMEN

BACKGROUND: Designed mimetic molecules are attractive tools in biopharmaceuticals and synthetic biology. They require mass and functional production for the assessment of upcoming challenges in the near future. The DARPin family is considered a mimetic pharmaceutical peptide group with high affinity binding to specific targets. DARPin G3 is designed to bind to the HER2 (human epidermal growth factor receptor 2) tyrosine kinase receptor. Overexpression of HER2 is common in some cancers, including breast cancer, and can be used as a prognostic and predictive tool for cancer. The chloroplasts are cost-effective alternatives, equal to, and sometimes better than, bacterial, yeast, or mammalian expression systems. This research examined the possibility of the production of the first antibody mimetic, DARPin G3, in tobacco chloroplasts for HER2 imaging in oncology. RESULTS: The chloroplast specific DARPin G3 expression cassette was constructed and transformed into N. tabacum chloroplasts. PCR and Southern blot analysis confirmed integration of transgenes as well as chloroplastic and cellular homoplasmy. The Western blot analysis and ELISA confirmed the production of DARPin G3 at the commercial scale and high dose with the rate of 20.2% in leaf TSP and 33.7% in chloroplast TSP. The functional analysis by ELISA confirmed the binding of IMAC purified chloroplast-made DARPin G3 to the extracellular domain of the HER2 receptor with highly effective picomolar affinities. The carcinoma cellular studies by flow cytometry and immunofluorescence microscopy confirmed the correct functioning by the specific binding of the chloroplast-made DARPin G3 to the HER2 receptor on the surface of HER2-positive cancer cell lines. CONCLUSION: The efficient functional bioactive production of DARPin G3 in chloroplasts led us to introduce plant chloroplasts as the site of efficient production of the first antibody mimetic molecules. This report, as the first case of the cost-effective production of mimetic molecules, enables researchers in pharmaceuticals, synthetic biology, and bio-molecular engineering to develop tool boxes by producing new molecular substitutes for diverse purposes.


Asunto(s)
Humanos , Animales , Productos Biológicos , Proteínas de Repetición de Anquirina Diseñadas , Preparaciones Farmacéuticas/metabolismo , Cloroplastos/metabolismo , Cloroplastos/química , Receptor ErbB-2 , Línea Celular Tumoral , Mamíferos/metabolismo
6.
Physiol Mol Biol Plants ; 26(4): 829-839, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32255943

RESUMEN

DUF538 (domain of unknown function 538) proteins are known as a group of putative hypothetical proteins in a wide range of plant species. They have been identified from some plants challenged with various environmental stresses. However, a little is known about their functional properties. They have been newly predicted to have binding capacity and esterase-type hydrolytic activity towards bacterial lipopolysaccharides and chlorophyll molecules as carboxylic compounds in plants. In the present study, the binding ability and the methylesterase activity of DUF538 proteins towards pectin molecules were also predicted. Their similarities to pectin methylesterases and their binding ability to pectin molecule were predicted using bioinformatic tools as well as the experimental method. A probable cooperation was speculated between DUF538 and pectin methylesterase protein families in cell wall associated defense responses in plants.

7.
Physiol Mol Biol Plants ; 25(1): 243-251, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30804646

RESUMEN

Considering Celosia plumosa as a potent antiviral plant, the attempt was made to determine, purify and characterize its proteinaceous antiviral elements against tobacco mosaic virus hypersensitive response on Nicotiana glutinosa. By using 60% ammonium sulphate-precipitation, FPLC-based anion and cation-exchange chromatography in 10 and 50 mM NaCl, size-exclusion chromatography in 50 mM NaCl and SDS-PAGE 10%, a 25 kD antiviral protein with ribosome-inactivating/28S rRNase ability was purified from the leaves of C. plumosa at vegetative growth stage. The purified protein showed FRAP-based antioxidant activity in vitro and caused 1.7-fold and 1.4-fold increases in the growth rate of root system upon carborundum-based application on the root growth medium of N. glutinosa. The present work reports an antiviral protein with ribosome-inactivating, antioxidation and root developer potencies in C. plumosa as an edible or ornamental plant that may be useful in health and agricultural biotechnology in the future.

8.
Physiol Mol Biol Plants ; 22(1): 77-85, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27186021

RESUMEN

The possible hydrolytic activity towards chlorophyll molecules was predicted for DUF538 protein superfamily in plants. It was examined by using computational as well as experimental tools including in vitro chlorophyll degradation, antioxidant compounds production and in vivo real-time gene expression tests. Comparison of the computational data with the experimental results indicated that DUF538 proteins might be chlorophyll hydrolyzing enzyme (most probably carboxyesterase) which degrade chlorophyll molecules (66 % per 12 hrs) to produce new compounds (1.8 fold per 12 hrs) with antioxidant properties. The relevance of DUF538 gene expression level with the chlorophyll contents (2.8 fold increase per chlorophyll content of 50 %) of the drought-stressed leaves showed that chlorophyll degradation by DUF538 is most probably induced in response to stress stimuli. Despite membranous chlorophyll catabolic pathways, DUF538-dependent reactions is predicted to be occurred in the cytosol of the under stressed plants. We addressed as to whether chlorophyll breakdown to antioxidant compounds by DUF538 is a defense mechanism of plants against stress stimuli, in vivo? This question is going to be investigated in our next research project.

9.
Protein J ; 32(3): 163-71, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23456176

RESUMEN

DUF538 protein super family includes a number of plant proteins that their role is not yet clear. These proteins have been frequently reported to be expressed in plants under various stressful stimuli such as bacteria and elicitors. In order to further understand about this protein family we utilized bioinformatics tools to analyze its structure in details. As a result, plants DUF538 was predicted to be the partial structural homologue of BPI (bactericidal/permeability increasing) proteins in mammalian innate immune system that provides the first line of defense against different pathogens including bacteria, fungi, viruses and parasites. Moreover, on the base of the experimental data, it was identified that exogenously applied purified fused product of Celosia DUF538 affects the bacterial growth more possibly similar to BPI through the binding to the bacterial membranes. In conclusion, as the first ever time report, we nominated DUF538 protein family as the potential structural and functional homologue of BPI protein in plants, providing a basis to study the novel functions of this protein family in the biological systems in the future.


Asunto(s)
Péptidos Catiónicos Antimicrobianos/química , Péptidos Catiónicos Antimicrobianos/genética , Proteínas Sanguíneas/química , Proteínas Sanguíneas/genética , Celosia/genética , Familia de Multigenes , Proteínas de Plantas/genética , Plantas/genética , Secuencia de Aminoácidos , Animales , Péptidos Catiónicos Antimicrobianos/metabolismo , Péptidos Catiónicos Antimicrobianos/farmacología , Bacterias/efectos de los fármacos , Bacterias/crecimiento & desarrollo , Proteínas Sanguíneas/metabolismo , Proteínas Sanguíneas/farmacología , Celosia/química , Celosia/metabolismo , Humanos , Modelos Moleculares , Datos de Secuencia Molecular , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Proteínas de Plantas/farmacología , Plantas/química , Plantas/metabolismo , Ratas , Homología de Secuencia de Aminoácido
10.
Physiol Mol Biol Plants ; 18(3): 237-44, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23814438

RESUMEN

Nowadays, plant cysteine proteinase inhibitors "namely phytocystatins" have attracted researchers towards the identification of their molecular structures and novel physiological functions. Their important roles in plant developmental processes and different stress responses have been well known. In spite of advances in the understanding of phytocystatins, we lack enough data concerning their heterologous expression especially in the forms of fusion products that are most important whether for biochemical, pharmacological or clinical studies. The present work describes an easy method of expression, purification and functional characterization in Escherichia coli of maize cystatin as a part of maltose-binding fusion protein. Assessments revealed that upon expression of fused product the total antioxidation status of the induced recombinant cells is increased. This result leads to question 'Is there any parallel functional correlation between anti-proteolytic and anti-oxidative systems?' However, the present research will open a gate for the new studies regarding the putative communicative roles of these systems that may be existing in the biological world.

11.
Protein J ; 30(5): 351-8, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21710148

RESUMEN

As a usual response, plants induce/activate various proteins which are thought to be involved in defense mechanisms against the biotic and abiotic stresses they may be confronted with. The novel DUF538 domain containing proteins with unknown functions have been found to be induced/activated in response to different environmental stress stimuli in plants. In order to perform biochemical studies with these new plant stress-responsive proteins, a cDNA containing DUF538 domain was amplified from Celosia cristata full-length leaf expression library using a specific primer set. The isolated cDNA was subsequently expressed in Escherichia coli as a part of maltose-binding fusion protein (MBP-DUF538 construct) and purified at the yield of about 32 mg per liter of cell culture by affinity chromatography without affecting the recombinant bacterial cell growth. The purified fusion product was exogenously applied (10 µg per 4 cm(2)) on the leaves of Nicotiana tobaccum L. The results revealed that fused DUF538 protein does not induce morphological reposes, but elevates redox enzyme activities including catalase, peroxidase, polyphenol oxidase and phenyalanine ammonia lyase. This is the first time ever time report with respect to the heterologous expression of a plant stress-responsive DUF538 domain that may provide a basis to study its physiological roles and biochemical activities in vitro and in vivo.


Asunto(s)
Estrés Oxidativo/efectos de los fármacos , Proteínas de Plantas/biosíntesis , Proteínas de Plantas/farmacología , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/farmacología , Secuencia de Aminoácidos , Secuencia de Bases , Celosia/genética , Electroforesis en Gel de Poliacrilamida , Escherichia coli , Datos de Secuencia Molecular , Oxidación-Reducción , Oxidorreductasas/metabolismo , Fenilanina Amoníaco-Liasa/metabolismo , Fosforilación , Hojas de la Planta/efectos de los fármacos , Hojas de la Planta/metabolismo , Proteínas de Plantas/química , Proteínas de Plantas/genética , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Análisis de Secuencia de Proteína , Nicotiana/efectos de los fármacos , Nicotiana/enzimología , Nicotiana/metabolismo
12.
Indian J Biochem Biophys ; 48(6): 375-9, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22329238

RESUMEN

Identification of the molecular structure and novel biophysiological functions of plant cystatins or phytocystatins is of great interest in the field of molecular biology. The important requirements for these are the efficient production, purification and correctly folded forms of these proteins. We report here the cloning, easy expression and characterization of a sunflower multicystatin (SMC) as a functional fusion protein in E. coli. For the first time, the amplified cystatin coding region was expressed as a part of maltose-binding fusion protein using pMALc2X over-expression vector in TB1 strain of E. coli without affecting the recombinant bacterial growth. In comparison to the previously prepared recombinant SMC (rSMC), a high amount (-44 mg/L of bacterial cell culture) of purified fused SMC (fSMC) was obtained using single-step purification method. fSMC strongly inhibited papain activity in vitro as compared to Celosia single-domain cystatin. Purified fSMC may be used for basic biochemical, pharmacological or clinical studies without the cleavage of its fusion parts.


Asunto(s)
Cistatinas/genética , Helianthus/genética , Secuencia de Bases , Clonación Molecular , Cartilla de ADN , Escherichia coli/genética , Reacción en Cadena de la Polimerasa , Proteínas Recombinantes/genética
13.
Indian J Exp Biol ; 47(8): 684-9, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19775076

RESUMEN

In a basic research to determine the morpho-molecular interactions of plant tissues with EcoRI DNA restriction enzyme, it was demonstrated that this protein is capable of entering the sunflower and maize leaf cells using a plant tissue-abrading material and cleaving the genomic DNA at specific sites. This was inferred from the analysis of morphological patterns of EcoRI-treated leaf areas as well as using some molecular tests, including the cleavage pattern analysis of genomic DNA isolated from treated locations followed by ligation of cleaved fragments into EcoRI site of a DNA cloning vector system. The overall results indicated that the specific restriction of genomic DNA may happen following the entrance of EcoRI protein most likely into the nucleus of plant cells.


Asunto(s)
Compuestos Inorgánicos de Carbono/metabolismo , ADN de Plantas/metabolismo , Desoxirribonucleasa EcoRI/metabolismo , Plantas/metabolismo , Silicio/metabolismo , Sitios de Unión/genética , Transporte Biológico , ADN de Plantas/genética , Electroforesis en Gel de Agar , Helianthus/citología , Helianthus/genética , Helianthus/metabolismo , Células Vegetales , Hojas de la Planta/citología , Hojas de la Planta/genética , Hojas de la Planta/metabolismo , Plantas/genética , Zea mays/citología , Zea mays/genética , Zea mays/metabolismo
14.
Biotechnol Appl Biochem ; 42(Pt 3): 197-204, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-15842197

RESUMEN

Cystatins (cysteine proteinase inhibitors) have been recently used in plants as antiviral strategy against those viruses whose replication involves cysteine proteinase activity. We proposed an idea that cystatins may confer resistance by inhibition of a virus-induced cell-death phenomenon in which cysteine proteinases are active. To test this idea, a full-length cDNA library was constructed from the preflowering stage of Celosia cristata (crested cock's comb) leaves, and a cDNA clone with cystatin domain was isolated using an oligonucleotide probe designed on the basis of the conserved peptide of plant cystatins. It was expressed in an Escherichia coli expression system as a fusion protein. The purified recombinant product, termed 'celostatin' (Celosia cystatin), inhibited the enzymatic activity of papain indicating its cystatin activity and prevented TMV (tobacco mosaic virus)-induced hypersensitive-response cell death in Nicotiana glutinosa (a wild species of tobacco) leaves by 65-70% at the concentration of approx. 50 ng/ml. It also offered resistance against TMV and caused normal growth of the test plant. Since the activity of cysteine proteinases is not involved in the TMV replication process, we speculated that inhibition of the hypersensitive response by celostatin may be due to the inactivation of proteolysis involved in the plant cell death programme, a phenomenon that has already been reported in animal systems.


Asunto(s)
Muerte Celular/efectos de los fármacos , Celosia/química , Clonación Molecular , Cistatinas/farmacología , Inhibidores de Cisteína Proteinasa/metabolismo , Secuencia de Aminoácidos , Secuencia de Bases , Codón Iniciador , Codón de Terminación , Secuencia de Consenso , Secuencia Conservada , Cistatinas/genética , Cistatinas/aislamiento & purificación , Inhibidores de Cisteína Proteinasa/química , Inhibidores de Cisteína Proteinasa/genética , Inhibidores de Cisteína Proteinasa/aislamiento & purificación , ADN Complementario/química , ADN Complementario/genética , Escherichia coli/genética , Biblioteca de Genes , Datos de Secuencia Molecular , Sistemas de Lectura Abierta , Papaína/antagonistas & inhibidores , Extractos Vegetales/farmacología , Proteínas Recombinantes de Fusión/química , Proteínas Recombinantes de Fusión/metabolismo , Nicotiana/genética , Nicotiana/virología
15.
Protein Pept Lett ; 11(6): 551-61, 2004 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-15579125

RESUMEN

Plants antiviral proteins are being used as anticancer agents and inhibit other viral diseases in humans. We modified the purification protocol of the two N-terminally blocked antiviral glycoproteins, CCP-25 and CCP-27, purified from the leaves of Celosia cristata. This not only gave rise to single pure samples with few steps of purification but also resulted in N-terminally free proteins. The extra purity of the samples was analyzed by reverse phase HPLC. Deglycosylation studies of CCP-25 with PNGase F enzyme revealed that its asparagine or asparagine-linked glycon contents are negligible. Partial N-terminal sequence of the CCP-25 showed the sequence (ANDIS), which seems to be conserved among plant antiviral proteins.


Asunto(s)
Antivirales/aislamiento & purificación , Celosia/genética , Proteínas de Plantas/aislamiento & purificación , Secuencia de Aminoácidos , Antivirales/genética , Antivirales/farmacología , Bioensayo , Celosia/virología , Cromatografía Líquida de Alta Presión , Electroforesis en Gel de Poliacrilamida , Proteínas de Plantas/genética , Proteínas de Plantas/farmacología , Virus de Plantas/efectos de los fármacos , Alineación de Secuencia , Análisis de Secuencia de Proteína
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