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1.
Biochem Genet ; 61(5): 1827-1849, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36856940

RESUMO

Polycystic ovarian syndrome (PCOS) is a complex endocrine and metabolic condition with several potential causes. Insulin resistance is a hallmark of PCOS that often coexists with hirsutism, hyperandrogenism, being overweight, and hormonal imbalances. The functioning of multiple replication and transcription factors is regulated by tumor suppressor genes (TSGs), which play a crucial role in maintaining genomic integrity and controlling the cell cycle of granulosa cells. In the present study, we examined how three single nucleotide polymorphisms (SNPs) in TP53, a cell cycle regulatory gene, affect the risk of developing PCOS in a sample of an Iranian population. Genomic DNA was extracted from 200 PCOS patients and 200 healthy women to analyze TP53 rs17880604, rs1625895, and rs1042522 SNPs using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. Our findings revealed that the majority of PCOS cases were overweight [25 < body mass index (BMI) < 30]. A positive association was observed between the TP53 rs1042522 SNP and the risk of PCOS under codominant heterozygous and overdominant genetic patterns (odds ratio > 1). Meanwhile, a negative association was observed between TP53 SNPs (rs1625895, rs17880604) and susceptibility to PCOS under codominant heterozygous and dominant models of inheritance (odds ratio < 1). Moreover, different genotype and haplotype combinations of rs17880604/rs1625895/rs1042522 conferred a decreased risk of PCOS in our population. We found no statistical difference in the frequency of TP53 genotypes between PCOS cases and/or controls in terms of BMI, waist circumference, prolactin level, and markers of lipid and carbohydrate profile (P > 0.05). Molecular dynamic prediction showed that the missense substitution in the 17p13.1 position (rs1042522) could change the properties and secondary structure of the p53 protein. As inherited risk factors, TP53 variations may play a  pivotal role in the pathogenesis of PCOS among Iranian women. Replicated population-based studies on other ethnicities are required to find the genetic contribution of variants of TP53, or SNPs located in other TSGs, to the etiology of this endocrine disease.


Assuntos
Síndrome do Ovário Policístico , Humanos , Feminino , Estudos de Casos e Controles , Síndrome do Ovário Policístico/genética , Predisposição Genética para Doença , Proteína Supressora de Tumor p53/genética , Sobrepeso/genética , Irã (Geográfico) , Frequência do Gene , Genótipo , Polimorfismo de Nucleotídeo Único , Ciclo Celular , Genes Reguladores
2.
J Biomol Struct Dyn ; 37(16): 4222-4237, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-30526389

RESUMO

Emerging widespread bacterial resistance to current antibiotics with traditional targets is one of the major global concerns. Therefore, so many investigations are exploring the potential of other druggable macromolecules of bacteria such as replication machinery components that are not addressed by previous antibiotics. DNA polymerase is the major part of this machine. However, a few studies have been done on it so far. In this respect, we report the discovery of four new plant-based leads against DNA polymerase (pol) IIIC (three leads) and pol IIIE (one lead) of Gram-positive and negative bacteria by combining a sequentially constrained high-throughput virtual screenings on Traditional Chinese Medicine Database with in vitro assays. The compounds displayed relatively good levels of inhibitory effect. They were active against their designated targets at micromolar concentrations. The IC50 values for them are ranged from 25 to 111 µM. In addition, they showed minimum inhibitory concentrations in the range of 8-128 µg/mL against five representatives of pathogenic bacteria species. However, they were inactive against Pseudomonas aeruginosa. Given these results, these leads hold promise for future modification and optimization to be more effective in lower concentrations and also against most of the important bacterial species. Communicated by Ramaswamy H. Sarma.


Assuntos
DNA Polimerase III/química , Replicação do DNA/efeitos dos fármacos , Chumbo/farmacologia , Inibidores da Síntese de Ácido Nucleico/farmacologia , Antibacterianos/efeitos adversos , Simulação por Computador , DNA Polimerase III/antagonistas & inibidores , Farmacorresistência Bacteriana/genética , Escherichia coli/efeitos dos fármacos , Escherichia coli/patogenicidade , Humanos , Chumbo/química , Testes de Sensibilidade Microbiana , Inibidores da Síntese de Ácido Nucleico/química , Células Procarióticas/efeitos dos fármacos , Células Procarióticas/microbiologia , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/patogenicidade
3.
Artigo em Inglês | MEDLINE | ID: mdl-29507581

RESUMO

Scorpions are distributed throughout Iran and the genus Hemiscorpius is particularly important in this region. Hemiscorpius lepturus is the most significant species within the genus in the country. Since scorpionism provoked by Hemiscorpius comprises a medical emergency, the present study is focused on this important issue. In order to perform the present work, a review of the medical and health-related literature was carried out in several databases. The current findings indicate that six species of Hemiscorpius are found in 15 states of Iran, mainly in the south and southwest. Deaths caused by stings were reported only for two species. The morphological characteristics and geographical distribution of H. lepturus in Iran, its venom and the toxic compounds, epidemiologic data and clinical manifestations of envenomation as well as treatment for affected people are herein reviewed and described. H. lepturus venom toxicity differs from other Iranian scorpions regarding duration and severity. Scorpionism is an important public health problem in Iran, especially in southwest and south regions and in urban areas. It is more prevalent in children and young people. H. lepturus venom is primarily a cytotoxic agent and has hemolytic, nephrotoxic and to some extent hepatotoxic activity. The use of polyvalent antivenom to prevent scorpion sting symptoms is recommended. A well-planned health education program might be useful in preventing scorpionism.

4.
Artigo em Inglês | LILACS | ID: biblio-894173

RESUMO

Scorpions are distributed throughout Iran and the genus Hemiscorpius is particularly important in this region. Hemiscorpius lepturus is the most significant species within the genus in the country. Since scorpionism provoked by Hemiscorpius comprises a medical emergency, the present study is focused on this important issue. In order to perform the present work, a review of the medical and health-related literature was carried out in several databases. The current findings indicate that six species of Hemiscorpius are found in 15 states of Iran, mainly in the south and southwest. Deaths caused by stings were reported only for two species. The morphological characteristics and geographical distribution of H. lepturus in Iran, its venom and the toxic compounds, epidemiologic data and clinical manifestations of envenomation as well as treatment for affected people are herein reviewed and described. H. lepturus venom toxicity differs from other Iranian scorpions regarding duration and severity. Scorpionism is an important public health problem in Iran, especially in southwest and south regions and in urban areas. It is more prevalent in children and young people. H. lepturus venom is primarily a cytotoxic agent and has hemolytic, nephrotoxic and to some extent hepatotoxic activity. The use of polyvalent antivenom to prevent scorpion sting symptoms is recommended. A well-planned health education program might be useful in preventing scorpionism.(AU)


Assuntos
Humanos , Animais , Venenos de Escorpião/toxicidade , Escorpiões/anatomia & histologia , Antivenenos/uso terapêutico , Picadas de Escorpião/terapia , Picadas de Escorpião/epidemiologia , Picadas de Escorpião/prevenção & controle , Ira
5.
J. venom. anim. toxins incl. trop. dis ; 24: 1-10, 2018. ilus, map
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1484744

RESUMO

Scorpions are distributed throughout Iran and the genus Hemiscorpius is particularly important in this region. Hemiscorpius lepturus is the most significant species within the genus in the country. Since scorpionism provoked by Hemiscorpius comprises a medical emergency, the present study is focused on this important issue. In order to perform the present work, a review of the medical and health-related literature was carried out in several databases. The current findings indicate that six species of Hemiscorpius are found in 15 states of Iran, mainly in the south and southwest. Deaths caused by stings were reported only for two species. The morphological characteristics and geographical distribution of H. lepturus in Iran, its venom and the toxic compounds, epidemiologic data and clinical manifestations of envenomation as well as treatment for affected people are herein reviewed and described. H. lepturus venom toxicity differs from other Iranian scorpions regarding duration and severity. Scorpionism is an important public health problem in Iran, especially in southwest and south regions and in urban areas. It is more prevalent in children and young people. H. lepturus venom is primarily a cytotoxic agent and has hemolytic, nephrotoxic and to some extent hepatotoxic activity. The use of polyvalent antivenom to prevent scorpion sting symptoms is recommended. A well-planned health education program might be useful in preventing scorpionism.


Assuntos
Animais , Distribuição Animal , Escorpiões , Picadas de Escorpião/epidemiologia , Venenos de Escorpião , Epidemias/prevenção & controle , Irã (Geográfico) , Literatura de Revisão como Assunto
6.
Int J Biol Macromol ; 93(Pt A): 526-533, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27608544

RESUMO

Methylglyoxal synthase (MGS) is a homohexameric enzyme responsible for converting dihydroxyacetone phosphate (DHAP) to methylglyoxal and phosphate in the methylglyoxal bypass of glycolysis. Phosphate acts as an allosteric inhibitor and strong regulator for this enzyme. Previous studies on MGS from Thermus sp. GH5 (TMGS) had indicated a pathway for transmitting the signal through Pro82, Arg97 and Val101 to the active site. The necessity of these residues for heterotropic negative cooperativity between subunits of TMGS were also proposed. In this study, it has been shown that a path via a salt bridge between Arg80 and Asp100 in the narrow dimer interface provides an alternative pathway for transmission of the allosteric inhibitory signal through subunit interfaces.


Assuntos
Carbono-Oxigênio Liases/química , Carbono-Oxigênio Liases/metabolismo , Temperatura , Thermus/enzimologia , Regulação Alostérica/efeitos dos fármacos , Sequência de Aminoácidos , Carbono-Oxigênio Liases/genética , Estabilidade Enzimática , Ligação de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Cinética , Modelos Moleculares , Fosfatos/farmacologia , Estrutura Secundária de Proteína
7.
Appl Biochem Biotechnol ; 172(1): 157-67, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24057302

RESUMO

Lately it has been proposed that interaction between two positively charged side chains can stabilize the folded state of proteins. To further explore this point, we studied the effect of histidine-histidine interactions on thermostability of methylglyoxal synthase from Thermus sp. GH5 (TMGS). The crystal structure of TMGS revealed that His23, Arg22, and Phe19 are in close distance and form a surface loop. Here, two modified enzymes were produced by site-directed mutagenesis (SDM); one of them, one histidine (TMGS-HH(O)), and another two histidines (TMGS-HHH(O)) were inserted between Arg22 and His23 (H(O)). In comparison with the wild type, TMGS-HH(O) thermostability increased remarkably, whereas TMGS-HHH(O) was very unstable. To explore the role of His23 in the observed phenomenon, the original His23 in TMGS-HHH(O) was replaced with Ala (TMGS-HHA). Our data showed that the half-life of TMGS-HHA decreased in relation to the wild type. However, its half-life increased in comparison with TMGS-HHH(O). These results demonstrated that histidine-histidine interactions at position 23 in TMGS-HH(O) probably have the main role in TMGS thermostability.


Assuntos
Carbono-Oxigênio Liases/química , Carbono-Oxigênio Liases/genética , Dipeptídeos , Mutagênese Sítio-Dirigida , Sequência de Aminoácidos , Carbono-Oxigênio Liases/metabolismo , Ativação Enzimática , Estabilidade Enzimática , Meia-Vida , Histidina , Cinética , Modelos Moleculares , Mutação , Conformação Proteica , Temperatura , Thermus/enzimologia
8.
Arch Iran Med ; 14(1): 8-11, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21194254

RESUMO

BACKGROUND: Co-inheritance of ß- and δ-globin mutations in Iran is not uncommon. This situation may interfere with correct diagnosis and genetic counseling of α- and ß-thalassemia in screening programs. Here we report the co-inheritance of ß- and δ-globin gene mutations in an individual with microcytosis, hypochromia and a normal hemoglobin A2 (HbA2) level. METHODS: Genomic DNA extraction, amplification refractory mutation system (ARMS) polymerase chain reaction and direct DNA sequencing of δ- and ß-globin genes were exploited for detection of the mutations in these two genes in an individual with low hematological indices and normal HbA2. RESULTS: ARMS-PCR technique revealed the ß(+) IVSI-5 (G to C) mutation and direct DNA sequencing of the δ-globin gene detected a previously reported delta codon 12 (AAT-->AAA) HbA2-NYU. This study reports HbA2-NYU in association with the ß IVSI-5 (G to C) mutation in Iran. DISCUSSION: This report emphasizes that normal HbA2 expression in a ß-goblin carrier is due to mutation in the δ-globin gene and may cause misdiagnosis of thalassemia.


Assuntos
Padrões de Herança/genética , Mutação Puntual , Globinas beta/genética , Talassemia beta/genética , Talassemia delta/genética , Adulto , Análise Mutacional de DNA , Diagnóstico Diferencial , Feminino , Hemoglobina A2/análise , Hemoglobina A2/genética , Hemoglobinas Anormais/análise , Hemoglobinas Anormais/genética , Humanos , Irã (Geográfico) , Masculino , Programas de Rastreamento , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Talassemia beta/sangue , Talassemia beta/diagnóstico , Globinas delta/genética , Talassemia delta/sangue , Talassemia delta/diagnóstico
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