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1.
Biotechnol Lett ; 44(5-6): 703-712, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35524923

RESUMO

Gliomas are highly invasive and lethal malignancy that do not respond to current therapeutic approaches. Novel therapeutic agents are required to target molecular mechanisms involved in glioma progression. MeICT is a new short-chain toxin isolated from Mesobuthus eupeus scorpion venom. This toxin contained 34 amino acid residues and belongs to chloride channels toxins. In this study, the coding sequence of MeICT was cloned into the pET32Rh vector and a high yield of soluble recombinant MeICT was expressed and purified. Recombinant MeICT-His significantly inhibited the proliferation and migration of glioma cells at low concentration. In vivo studies showed that MeICT was not toxic when administrated to mice at high doses. We also determined the effect of MeICT on the mRNA expression of MMP-2, Annexin A2 and FOXM-2 that are key molecules in the progression and invasion of glioma. Expression of Annexin A2 and FOXM1 mRNA was significantly down-regulated following treatment with MeICT. However, no significant decrease in the expression of MMP-2 gene was identified. In this study a short toxin with four disulfide bonds was successfully produced and its anti-cancer effects was detected. Our findings suggest that recombinant MeICT can be considered as a new potent agent for glioma targeting.


Assuntos
Anexina A2 , Glioma , Venenos de Escorpião , Sequência de Aminoácidos , Animais , Anexina A2/genética , Proliferação de Células , Glioma/tratamento farmacológico , Metaloproteinase 2 da Matriz/genética , Camundongos , RNA Mensageiro , Venenos de Escorpião/genética , Escorpiões/química , Escorpiões/genética
2.
Biochem Genet ; 60(2): 504-526, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34286408

RESUMO

Different toxins acting on Kv1.3 channel have been isolated from animal venom. MeuKTX toxin from Mesobuthus eupeus phillipsi scorpion and shtx-k toxin from Stichodactyla haddoni sea anemone have been identified as two effective Kv1.3 channel blockers. In this work, we characterized the genomic organization of both toxins. MeuKTX gene contains one intron and two exons, similar to the most scorpion toxins. There are a few reports of genomic structure of sea anemone toxins acting on Kv channels. The sequence encoding mature peptide of shtx-k was located in an exon separated by an intron from the coding exon of the propeptide and signal region. In order to make a peptide with more affinity for Kv1.3 channel and greater stability, the shtx-k/ MeuKTX chimeric peptide was designed and constructed using splicing by overlap extension-PCR (SOE-PCR) method. MeuKTX, shtx-k, and shtx-k/MeuKTX were cloned and the expression of the soluble proteins in E. coli was determined. Molecular docking studies indicated more inhibitory effect of shtx-k/MeuKTX on Kv1.3 channel compared to shtx-k and MeuKTX toxins. Key amino acids binding channel from both toxins, also involved in interaction of chimeric peptide with channel. Our results showed that the fusion peptide, shtx-k/MeuKTX could be an effective agent to target Kv1.3 channel.


Assuntos
Venenos de Escorpião , Anêmonas-do-Mar , Sequência de Aminoácidos , Animais , Escherichia coli , Genômica , Simulação de Acoplamento Molecular , Peptídeos/química , Peptídeos/genética , Peptídeos/farmacologia , Bloqueadores dos Canais de Potássio/química , Bloqueadores dos Canais de Potássio/metabolismo , Bloqueadores dos Canais de Potássio/farmacologia , Venenos de Escorpião/química , Venenos de Escorpião/genética , Escorpiões/química , Escorpiões/genética , Escorpiões/metabolismo , Anêmonas-do-Mar/química , Anêmonas-do-Mar/genética , Anêmonas-do-Mar/metabolismo
3.
Mol Cancer ; 18(1): 75, 2019 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-30940145

RESUMO

Tumor-derived exosomes (TDEs) participate in formation and progression of different cancer processes, including tumor microenvironment (TME) remodeling, angiogenesis, invasion, metastasis and drug-resistance. Exosomes initiate or suppress various signaling pathways in the recipient cells via transmitting heterogeneous cargoes. In this review we discuss exosome biogenesis, exosome mediated metastasis and chemoresistance. Furthermore, tumor derived exosomes role in tumor microenvironment remodeling, and angiogenesis is reviewed. Also, exosome induction of epithelial mesenchymal transition (EMT) is highlighted. More importantly, we discuss extensively how exosomes regulate drug resistance in several cancers. Thus, understanding exosome biogenesis, their contents and the molecular mechanisms and signaling pathways that are responsible for metastasis and drug-resistance mediated by TDEs may help to devise novel therapeutic approaches for cancer progression particularly to overcome therapy-resistance and preventing metastasis as major factors of cancer mortality.


Assuntos
Resistencia a Medicamentos Antineoplásicos , Exossomos/metabolismo , Neoplasias/metabolismo , Progressão da Doença , Humanos , Metástase Neoplásica , Transdução de Sinais , Microambiente Tumoral
4.
Ecotoxicol Environ Saf ; 113: 259-70, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25528376

RESUMO

Silver nanoparticles (AgNPs) are one of the most widely used nanomaterials, although the mechanisms of AgNP toxicity in terrestrial plants is still unclear. We compared the toxic effects of AgNPs and AgNO3 on Brassica nigra seed germination at physiological and molecular levels. Both AgNPs and AgNO3 inhibited seed germination, lipase activity, soluble and reducing sugar contents in germinating seeds and seedlings. These reductions were more pronounced in AgNP treatments than AgNO3 treatments. Application of 200-400mg/L both AgNPs and AgNO3 increased transcription of heme oxygenase-1. However, at 800, 1600 mg/L, AgNPs or AgNO3 suppressed HO-1 expression. At 400mg/L, AgNPs or AgNO3-induced inhibitory effects on seed germination and were ameliorated by the HO-1 inducer, hematin, or NO donor, sodium nitroprusside (SNP). Additionally, 4 µM hematin and 400 µM SNP were able to markedly boost the HO/NO system. However, the addition of the HO-1 inhibitor (ZnPPIX) or the specific scavenger of NO (cPTIO) not only reversed the protective effects conferred by hematin, but also blocked the up-regulation of HO activity. In addition, hematin-drived NO production in B. niger seeds under AgNPs was confirmed. Our results at physiological and molecular levels suggested that AgNPs were more toxic than AgNO3. Based on these results, for the first time, we suggest that endogenous HO is needed to alleviate AgNPs-induced germination inhibition, which might have a possible interaction with NO.


Assuntos
Germinação/efeitos dos fármacos , Hemina/administração & dosagem , Mostardeira/efeitos dos fármacos , Nitroprussiato/administração & dosagem , Nitrato de Prata/toxicidade , Prata/toxicidade , Heme Oxigenase (Desciclizante)/metabolismo , Lipase/efeitos dos fármacos , Nanopartículas Metálicas/toxicidade , Mostardeira/enzimologia , Mostardeira/crescimento & desenvolvimento , Óxido Nítrico/metabolismo , Plantas/metabolismo , Plântula/efeitos dos fármacos , Plântula/crescimento & desenvolvimento , Sementes/efeitos dos fármacos , Prata/metabolismo , Regulação para Cima
5.
Brain Res ; 1838: 148966, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38688382

RESUMO

Thymus vulgaris and Allium cepa are plants with great medicinal importance. Thymol monoterpene and quercetin, which are present in these plants, have anti-Alzheimer's and antioxidant effects. The objectives of this research were investigating the effects of these compounds on the pathogenesis and progress of Alzheimer's disease in cells modeled by formaldehyde. MTT, flow cytometry, and RT-PCR were used to investigate the toxicity, survival rate and apoptosis of the cells, and the expression level of PP2A, GSK3, NMDAR, BACE1, and APP genes, respectively. Also, the total antioxidant capacity of the modeled cells was measured. The results showed that the two compounds as well as the plants extract and essential oil were able to increase the percentage of cell survival; among them, Thymus vulgaris essential oil had the greatest effect (93.55316 % in 48 h exposure). In addition, quercetin was able to reduce the rate of apoptosis in Alzheimer's cells (4.73 %) which was greater than the effects of other compounds. In general, the essential oil of Thymus vulgaris compared to thymol; and quercetin compared to Allium cepa extract showed more improving effects on the expression of genes involved in the disease. All four compounds increased the antioxidant capacity of the modeled cells compared to the control group, and these effects were almost equal between the compounds. According to the obtained results, both plants, especially Thymus vulgaris can be proposed as candidates to be included in the diet of Alzheimer's patients. In addition, polyphenols thymol and quercetin as derivates from the studied plants can be used in new drugs development for Alzheimer's disease, with greater safety than currently used drugs. These results are significant because most of the drug for Alzheimer's treatments such as cholinesterases (e.g. rivastigmine and donepezil) and memantine are chemically based and have many side effects.


Assuntos
Doença de Alzheimer , Antioxidantes , Óleos Voláteis , Cebolas , Extratos Vegetais , Quercetina , Timol , Thymus (Planta) , Quercetina/farmacologia , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Doença de Alzheimer/genética , Extratos Vegetais/farmacologia , Óleos Voláteis/farmacologia , Ratos , Animais , Timol/farmacologia , Antioxidantes/farmacologia , Células PC12 , Sobrevivência Celular/efeitos dos fármacos , Apoptose/efeitos dos fármacos
6.
Psychopharmacol Bull ; 53(3): 22-34, 2023 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-37601086

RESUMO

Objectives: A growing body of evidence has recently suggested that taking venlafaxine during pregnancy may be linked to increased risk of certain congenital defects. The study aimed to address the effects of venlafaxine use during pregnancy on the development of the brain in mice. Experimental design: Fourteen female BALB/c mice were randomly divided into two equally-sized groups: venlafaxine-treated and control. After mating, pregnant mice of venlafaxine-treated group were orally received the venlafaxine 35 mg/kg/day throughout pregnancy, while pregnant control mice did not receive any treatment. All pups were killed on postnatal day 21 and brain images were quantified using ImageJ software. The mRNA expression levels of SHANK3, TUBB5 and DDC of genes in pups' brain tissue samples were evaluated using quantitative real-time PCR method. Principal observations: The mean brain size of pups was significantly smaller in the venlafaxine-treated group than in the control group. Results showed that the mRNA expression levels of SHANK3 and TUBB5 was significantly downregulated in venlafaxine-treated mice compared to control group. Expression of DDC gene didn't showed significant differences between two groups. Conclusions: These results provide evidence that use of venlafaxine during pregnancy may affect the brain development in mice and altered the expression of SHANK3 and TUBB5 genes in brain tissue.


Assuntos
Encéfalo , Proteínas do Tecido Nervoso , Cloridrato de Venlafaxina , Animais , Feminino , Camundongos , Gravidez , Descarboxilases de Aminoácido-L-Aromático , Encéfalo/efeitos dos fármacos , Proteínas do Tecido Nervoso/genética , RNA Mensageiro , Cloridrato de Venlafaxina/farmacologia
7.
Mol Biol Res Commun ; 12(1): 27-36, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37201031

RESUMO

Scorpion venom contains various toxin peptides with pharmacological and biological properties. Scorpion toxins specifically interact with membrane ion channels which play key roles in progression of cancer. Therefore, scorpion toxins have received special attention for targeting cancer cells. Two new toxins MeICT and IMe-AGAP, isolated from Iranian yellow scorpion, Mesobuthus eupeus, interact specifically with chloride and sodium channels, respectively. Anti-cancer properties of MeICT and IMe-AGAP have been determined before, in addition they show 81 and 93% similarity with two well-known anti-cancer toxins, CTX and AGAP, respectively. The aim of this study was construction of a fusion peptide MeICT/IMe-AGAP to target different ion channels involved in cancer progression. Design and structure of the fusion peptide were investigated by bioinformatics studies. Two fragments encoding MeICT and IMe-AGAP were fused using overlapping primers by SOEing-PCR. MeICT/IMe-AGAP chimeric fragment was cloned into pET32Rh vector, expressed in Escherichia coli host and analyzed by SDS-PAGE. The in silico studies showed that chimeric peptide with GPSPG linker preserved the three-dimensional structure of both peptides and can be functional. Due to the high expression of chloride and sodium channels in various cancer cells, MeICT/IMe-AGAP fusion peptide can be used as an effective agent to target both channels in cancers, simultaneously.

8.
Indian J Med Microbiol ; 41: 13-18, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36870742

RESUMO

PURPOSE: Leishmaniasis is one of the most serious health problems in developing countries. Iran is one of the endemic regions of cutaneous leishmaniasis. Leishmania RNA virus (LRV) is a dsRNA virus member of the Totiviridae family, which was first detected in the promastigotes of Leishmania braziliensis guyanensis. Our study aimed to investigate possible changes in the predominant and causative strains of CL and screening the LRV1 and LRV2 species genome from Leishmania species isolated from the lesions of patients. MATERIALS AND METHODS: Direct smear samples obtained from 62 patients with leishmaniasis referring to the Skin Diseases and Leishmaniasis Research Center in Isfahan province during 2021-2022 were examined. Total DNA extraction procedures and conservation of site-specific multiplex PCR and nested PCR were performed for detecting Leishmania species. The molecular identification of LRV1 and LRV2 viruses, samples were used for total RNA extraction and real-time (RT)-PCR analysis, followed by conducting a restriction enzyme assay to confirm the PCR products. RESULTS: Of the total Leishmania isolates, 54 and 8 isolates were identified as L. major and L. tropica, respectively. LRV2 was identified in 18 samples affected by L. major, while LRV1 was only detected in one of the samples with L. tropica. No LRV2 was found in any samples with L. tropica. The results showed that there was a significant relationship between LRV1 and the type of leishmaniasis (Sig. â€‹= â€‹0.009, P â€‹≤ â€‹0.05), while this relationship was not observed between LRV2 and the type of leishmaniasis. CONCLUSIONS: The presence of a significant number of LRV2 in isolated samples, as well as the recognition of LRV1 in one of the Old World leishmaniasis species, which is a new result, could pave the way for investigating further aspects of this disease and successful treatment strategies in future studies.


Assuntos
Leishmania , Leishmaniose Cutânea , Vírus , Humanos , Irã (Geográfico) , Reação em Cadeia da Polimerase Multiplex
9.
J Food Biochem ; 46(7): e14097, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35102562

RESUMO

Okra (Abelmoschus esculentus (L.) Moench) is one of the most important medicinal plants for the treatment of diabetes. Flavonoids are one of the most significant components of okra and are responsible for their antioxidant, anti-inflammatory, and anti-diabetic effects. The aim of this research was to investigate the effect of okra extract on biochemical parameters and expression of protein tyrosine phosphatase 1B (PTP1B) and Peroxisome proliferator-activated receptors (PPARs) genes in a model of streptozotocin-induced diabetic male Wistar rat. Rats were given oral dosages of okra extract, (75% ethanolic extract) (200-400 mg/kg) for eight weeks. Our findings indicate that okra extract and quercetin therapy may lower blood glucose (BS), insulin, Triglyceride (TG), Cholesterol (Cho), and glucose transporter protein type-4 (GLUT4) levels. PTP1B and Peroxisome proliferator-activated receptor alpha (PPAR-α), which are important regulators of glucose and lipid homeostasis, are similarly inhibited by okra extract. According to the findings, okra extract also has antioxidant properties. Our results support the anti-hyperglycemic and hypolipidemic properties of okra extract. As a result, it appears to play a crucial role in controlling diabetes. PRACTICAL APPLICATIONS: In this paper, we show that flavonoids in okra may help diabetes by inhibiting the PTP1B and PPAR-pathways. This is significant because little research has been done on the impact of flavonoid chemicals in A. esculentus on the expression of PTP1B and PPAR using traditional methods of diabetes treatment. Many of today's essential drugs (e.g., atropine, ephedrine, tubocurarine, digoxin, and reserpine) have been developed by studding traditional treatments. Plant-derived medications are still used as a prototype by chemists in an effort to develop more effective and less risky treatments (e.g., morphine, taxol, physostigmine, quinidine, and emetine.


Assuntos
Abelmoschus , Diabetes Mellitus Experimental , Abelmoschus/química , Animais , Antioxidantes/química , Glicemia , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/genética , Flavonoides/farmacologia , Lipídeos , Masculino , PPAR alfa/genética , Monoéster Fosfórico Hidrolases , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Ratos , Ratos Wistar
10.
J Food Biochem ; 46(12): e14506, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36369969

RESUMO

Phosphoenolpyruvate carboxykinase (PEPCK) is a key enzyme in the glyconeogenesis pathway. The AMP-activated protein kinase alpha (AMPK-α) pathway regulates PEPCK, which itself is activated by the AMP/ATP ratio and liver kinase B1 (KB1). The Abelmoschus esculentus (L.) Moench (okra) plant contains a large amount of quercetin that can function as an agonist or an antagonist. The aim of this study was to examine the effects of quercetin flavonoid and A. esculentus extract on the level of AMPK-α expression and associated metabolic pathways. The findings demonstrate that metformin, quercetin, and okra extract may significantly raise AMPK-α levels while significantly lowering PEPCK and hormone-sensitive lipase (HSL) levels, in addition to improving glucose and lipid profiles. By stimulating KB1, these substances increased AMPK-α activation. Additionally, AMPK-α activation improved insulin resistance and Glucose transporter type 4 (GLUT4) gene expression levels. Since AMPK-α maintains energy balance and its activity has not been reported to be inhibited so far, it could be a potent therapeutic target. PRACTICAL APPLICATIONS: The development of effective AMPK-α agonists and antagonists holds promise for the treatment of metabolic disorders like diabetes. Dietary polyphenols are a valuable source for developing new drugs. However, due to the lack of understanding of the underlying mechanisms of their effect on cells, their use in the treatment of diabetes is controversial. In addition to chemicals that have medicinal benefits, chemists are searching for less harmful substances. Using plants containing bioactive chemicals for this purpose can be a good alternative to chemical drugs.


Assuntos
Abelmoschus , Diabetes Mellitus Experimental , Ratos , Animais , Glicemia/metabolismo , Abelmoschus/química , Abelmoschus/metabolismo , Proteínas Quinases Ativadas por AMP/genética , Quercetina/farmacologia , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/metabolismo , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Lipídeos
11.
J Equine Vet Sci ; 119: 104134, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36202292

RESUMO

One of the initial responses of the host's innate immunity of newborns against pathogens is the use of oxidative enzymes. This study aimed to evaluate changes in serum xanthine oxidoreductase (XOR) activity, the leukocyte myeloperoxidase (MPO) and XOR genes expression, and some biochemical parameters in healthy Darehshuri newborn foals up to 60 days of life. Blood samples were collected from 16 foals at 1, 7, 15, 30, and 60 days and used for detecting XOR activity, biochemical parameters, and also gene expression by real-time RT-PCR. High activity of XOR was observed at birth, explained by physiologic hypoxia during the birth without sex difference. The significant decrease in XOR activity during the following days is probably related to the decreased levels of substrate and feedback inhibition of XOR by uric acid. No correlations were found between XOR activity and uric acid. A positive correlation was observed between XOR mRNA and serum XOR activity in 15 days. The results also indicate higher levels of MPO gene expression at 30 days, which may be associated with their capacity for neutrophil phagocytosis. The concentrations of creatinine, total protein, and albumin were higher at birth, whereas uric acid level was lower (P < 0.05). It can be concluded that XOR activity decreases with age and there is no significant change in its gene expression and MPO expression increases with age and is sex-dependent. There is an influence of age on XOR activity, leukocyte expression of MPO, and biochemical parameters in healthy newborn foals up to 60 days of life.


Assuntos
Ácido Úrico , Xantina Desidrogenase , Cavalos , Animais , Feminino , Masculino , Xantina Desidrogenase/genética , Animais Recém-Nascidos , Leucócitos/metabolismo , Expressão Gênica
12.
Sci Rep ; 11(1): 12537, 2021 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-34131166

RESUMO

Differentiation therapy is attracting increasing interest in cancer as it can be more specific than conventional chemotherapy approaches, and it has offered new treatment options for some cancer types, such as treating acute promyelocytic leukaemia (APL) by retinoic acid. However, there is a pressing need to identify additional molecules which act in this way, both in leukaemia and other cancer types. In this work, we hence developed a novel transcriptional drug repositioning approach, based on both bioinformatics and cheminformatics components, that enables selecting such compounds in a more informed manner. We have validated the approach for leukaemia cells, and retrospectively retinoic acid was successfully identified using our method. Prospectively, the anti-parasitic compound fenbendazole was tested in leukaemia cells, and we were able to show that it can induce the differentiation of leukaemia cells to granulocytes in low concentrations of 0.1 µM and within as short a time period as 3 days. This work hence provides a systematic and validated approach for identifying small molecules for differentiation therapy in cancer.


Assuntos
Reposicionamento de Medicamentos/tendências , Fenbendazol/química , Leucemia Promielocítica Aguda/tratamento farmacológico , Tretinoína/química , Quimioinformática/tendências , Fenbendazol/uso terapêutico , Humanos , Tretinoína/uso terapêutico
13.
Int J Prev Med ; 11: 18, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32175058

RESUMO

BACKGROUND: There are numerous couples worldwide currently suffering from infertility. Several factors, including genetic abnormalities are involved in infertility. In this study, we investigated the expression of myc gene in uterine tissue of infertile women. The protein encoded by this gene is one of the important transcription factors involved in the expression of many genes in the embryonic growth, and development pathways. METHODS: There are about 45 samples of uterine tissue from women with primary and secondary infertility were involved in this study. After extracting RNA and synthesizing cDNA, using specific primers for the myc gene and the beta-actin gene (as an internal control), gene expression was evaluated by Real-time RT-PCR method. RESULTS: The results of myc gene expression analysis showed no significant pattern between the affected and healthy women, however decreasing of its expression should not be rejected. CONCLUSIONS: This study is the first report about myc gene expression and its relation with the primary and secondary infertility. Myc gene expression study at different times of sexual period of infertile woman is suggested. Also, we proposed here, as a preventive strategy, improvement of the expression level of myc gene by some methods, such as hormone therapy, can increase the implantation success in the infertile women.

14.
Neurol Neurochir Pol ; 42(3): 263-6, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18651333

RESUMO

Mitochondrial DNA (mtDNA) mutations are an important cause of human diseases. mtDNA could be considered a candidate modifying factor in neurodegenerative disorders. A homoplasmic A8296G mutation was detected in a 24-year-old patient with idiopathic generalized epilepsy. The A8296G mutation in the mitochondrial DNA MT-TK gene has been associated with severe mitochondrial diseases. The pathogenicity of this mutation or its association with a specific disease is unclear. This mutation has already been reported exclusively as well as together with other mutations during trials of mtDNA. As in this case, the mutation was homoplasmic and there were no clinical findings in other family members. We suggest that this mutation is a rare polymorphism or may be a pathogenic mutation in combination with other mutations outside of the MT-TK gene.


Assuntos
Epilepsia/genética , Polimorfismo Genético , RNA de Transferência de Lisina/genética , Adulto , Humanos , Masculino , Mitocôndrias/genética , Mutação Puntual
15.
Appl Biochem Biotechnol ; 142(2): 200-8, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18025581

RESUMO

Molecular phylogenetic analysis of a novel thermophilic eubacterium isolated from an Iranian hot spring using 16S rDNA sequence showed that the new isolate belongs to genera Geobacillus. DNA pol I gene from this isolate was amplified, cloned, sequenced, and the three-dimensional (3D) structure of deduced amino acid sequence was predicted. Sequence analysis revealed the gene is 2,631 bp long, encodes a protein of 876 amino acids with a calculated molecular mass of 99 kDa, and belongs to family A DNA polymerases. Comparison of 3'-5'exonuclease domain of Klenow fragment (KF) with corresponding region of newly identified DNA pol I (MF), the large fragment of Bacillus stearothermophilus DNA pol I (BF) and Klentaq1, revealed not only deletions in three regions compared to KF, but that three of the four critical metal-binding residues in KF (Asp355, Glu357, Asp424, and Asp501) are altered in MF as well. Predicted 3D structure and sequence alignments between MF and BF showed that all critical residues in the polymerase active site are conserved.


Assuntos
Bacillaceae/enzimologia , DNA Polimerase I/química , Fontes Termais/microbiologia , Sequência de Aminoácidos , Bacillaceae/classificação , Clonagem Molecular , DNA Polimerase I/genética , DNA Ribossômico/química , Exonucleases/química , Irã (Geográfico) , Modelos Moleculares , Dados de Sequência Molecular , Filogenia , Estrutura Terciária de Proteína , Análise de Sequência
16.
J Clin Virol ; 32(4): 318-24, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15780812

RESUMO

BACKGROUND: Rapid, sensitive and economical detection and identification of human herpesviruses as causative agents of central nervous system (CNS) infections are of clinical importance. The traditional methods for the detection of herpesviruses in CNS infections all suffer from limitations. PCR has a potential to overcome each of them. OBJECTIVES: The aims of this study were reducing the number of primers in multiplex PCR and increasing the sensitivity of the assay by nested PCR. STUDY DESIGN: A multiplex nested consensus PCR (MNC-PCR) was developed for the simultaneous detection of major human herpesviruses. A pair of conserved primers was designed for detection of HSV-1, HSV-2, CMV and EBV and another pair of conserved primers for nested PCR. For VZV, a different pair of primers was designed and another pair of primers for nested PCR. A reduction in the number of designed primer pairs (from five pairs to two in both stages of PCR) is an advantage in this assay. One hundred forty-seven cerebral spinal fluid (CSF) samples from patients that showed clinical manifestation of CNS infections were tested. Results of MNC-PCR in CSF samples were compared with those of single PCR assay for each individual DNA virus. Sensitivity of the assay was determined with a plasmid containing VZV DNA binding protein gene and another plasmid for HSV-1 DNA polymerase gene. False negative results (due to the presence of inhibitor of DNA amplification in CSF samples) were avoided by the inclusion of beta2-microglobulin primers in the MNC-PCR assay as an internal control. RESULTS: Positive results were obtained in 20 CSF samples (8 HSV-1, 2 HSV-2, 4 CMV, 3 VZV, 3 HSV-1/CMV, CMV/VZV and HSV-1/EBV coinfections). The comparison between single PCR and MNC-PCR showed a marked increase in sensitivity of MNC-PCR test, since six negative samples in single PCR proved positive in MNC-PCR (P<0.005). Sensitivity was determined 1-5 plasmid copies for VZV and 50-100 plasmid copies for HSV-1. CONCLUSIONS: The MNC-PCR assay presented in this study can provide a rapid, sensitive and economical method for detection of viral infections and is applicable to small volumes of CSF samples.


Assuntos
Viroses do Sistema Nervoso Central/diagnóstico , DNA Viral/líquido cefalorraquidiano , Infecções por Herpesviridae/diagnóstico , Herpesviridae/isolamento & purificação , Reação em Cadeia da Polimerase/métodos , Adulto , Viroses do Sistema Nervoso Central/líquido cefalorraquidiano , Criança , Pré-Escolar , Primers do DNA , Feminino , Herpesviridae/genética , Infecções por Herpesviridae/líquido cefalorraquidiano , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade
17.
Viral Immunol ; 28(6): 325-30, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25965449

RESUMO

Rotavirus is the major etiologic factor of severe diarrheal disease. Natural infection provides protection against subsequent rotavirus infection and diarrhea. This research presents a new vaccine designed based on computational models. In this study, three types of epitopes are considered-linear, conformational, and combinational-in a proposed model protein. Several studies on rotavirus vaccines have shown that VP6 and VP4 proteins are good candidates for vaccine production. In the present study, a fusion protein was designed as a new generation of rotavirus vaccines by bioinformatics analyses. This model-based study using ABCpred, BCPREDS, Bcepred, and Ellipro web servers showed that the peptide presented in this article has the necessary properties to act as a vaccine. Prediction of linear B-cell epitopes of peptides is helpful to investigate whether these peptides are able to activate humoral immunity.


Assuntos
Biologia Computacional , Epitopos/imunologia , Vacinas contra Rotavirus/imunologia , Epitopos/genética , Humanos , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/imunologia , Vacinas contra Rotavirus/genética , Vacinas Sintéticas/genética , Vacinas Sintéticas/imunologia
18.
Res Vet Sci ; 93(1): 275-8, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21868048

RESUMO

The present research aimed at evaluating the effects of sodium selenite and selenium nanoparticles (Se NPs) on iron homeostasis and the expression of transferrin and its receptor-binding protein genes. Twenty one Lori-Bakhtiary sheep were randomly allocated into 3 groups. Groups 1 and 2 orally received Se NPs and sodium selenite (1 mg kg(-1)) for 10 consecutive days, respectively. Group 3 served as the control. Blood and sternal bone marrow samples were collected at different supplementation intervals. Various factors such as serum iron concentration, total iron binding capacity (TIBC), and transferrin saturation percent were determined. The expression of transferrin and transferrin binding receptor genes was also studied. Results showed a decreasing trend in serum iron concentration particularly during the early and middle stages of supplementation (0-20 days) with Se NPs or selenium ions. Conversely, the TIBC level increased in sera especially during these periods (0-20 days) in animals that received selenium NPs or selenium ions. Our results also showed that expression of transferrin and its receptor genes was considerably increased during supplementation of the animals by both selenium compounds for 10 or 20 days. After this period, the expression of the mentioned genes significantly decreased, especially in animals that received selenium ions.


Assuntos
Suplementos Nutricionais , Ferro/metabolismo , Selênio/farmacologia , Ovinos/metabolismo , Selenito de Sódio/farmacologia , Transferrina/biossíntese , Animais , Expressão Gênica/efeitos dos fármacos , Homeostase/efeitos dos fármacos , Ferro/sangue , Nanopartículas/uso terapêutico , Receptores da Transferrina/biossíntese , Receptores da Transferrina/sangue , Reação em Cadeia da Polimerase Via Transcriptase Reversa/veterinária , Selênio/administração & dosagem , Ovinos/fisiologia , Transferrina/análise
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