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1.
Cell Mol Biol (Noisy-le-grand) ; 63(8): 77-83, 2017 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-28886318

RESUMO

Spermatogenesis is proliferation and differentiation processes of stem spermatogonia into mature spermatozoa controlled by the genes responsible for transcription and post transcription levels. MicroRNAs (miRNA) are  the key factors during gene expression in RNA silencing and post-transcriptional regulation. They play main roles in regulation of early and late spermatogenesis, and reproduction. In this study, we investigate the role of miRNAs in infertile males.The patients were assigned to five groups based on semen analysis (n=55), including normozoospermic (N), moderate oligoasthenoteratozoospermic (MOAT), severe oligoasthenoteratozoospermic (SOAT), obstructive azoospermia (OA) and non-obstructive azoospermia (NOA). Quantitative RT-PCR was recruited to study the expression of miR-34c and tumor suppressor p53 gene. In addition, malondialdehyde (MDA) and DNA fragmentation was measured. Network analysis was performed using Pathway Studio web tool (Elsevier). Our results revealed statistically significant increased expression of miR-34c in moderate oligoasthenoteratozoospermic, non-obstructive azoospermia and an increased expression of p53 in MOAT, SOAT and NOA males. Also, the percentage of DNA fragmentation and oxidative stress was significantly higher in infertile groups (MOAT and SOAT) than other groups. These findings provide a novel molecular mechanism of gene regulation during cell-cycle and apoptosis in sperm, which gives a new regulatory insight into male infertility in terms of molecular diagnosis.


Assuntos
Azoospermia/genética , Infertilidade Masculina/genética , MicroRNAs/genética , Oligospermia/genética , Espermatozoides/metabolismo , Proteína Supressora de Tumor p53/genética , Adulto , Azoospermia/diagnóstico , Azoospermia/metabolismo , Azoospermia/patologia , Estudos de Casos e Controles , Fragmentação do DNA , Regulação da Expressão Gênica , Humanos , Infertilidade Masculina/diagnóstico , Infertilidade Masculina/metabolismo , Infertilidade Masculina/patologia , Masculino , Malondialdeído/metabolismo , MicroRNAs/metabolismo , Oligospermia/diagnóstico , Oligospermia/metabolismo , Oligospermia/patologia , Estresse Oxidativo , Análise do Sêmen , Índice de Gravidade de Doença , Transdução de Sinais , Espermatogênese/genética , Espermatozoides/patologia , Testículo/metabolismo , Testículo/patologia , Proteína Supressora de Tumor p53/metabolismo
2.
J Biomed Phys Eng ; 11(1): 61-72, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33564641

RESUMO

BACKGROUND: There are many studies to investigate the effects of each interacting component of tumor-immune system interactions. In all these studies, the distinct effect of each component was investigated. As the interaction of tumor-immune system has feedback and is complex, the alternation of each component may affect other components indirectly. OBJECTIVE: Because of the complexities of tumor-immune system interactions, it is important to determine the mutual behavior of such components. We need a careful observation to extract these mutual interactions. Achieving these observations using experiments is costly and time-consuming. MATERIAL AND METHODS: In this experimental and based on mathematical modeling study, to achieve these observations, we presented a fuzzy structured agent-based model of tumor-immune system interactions. In this study, we consider the confronting of the effector cells of the adaptive immune system in the presence of the cytokines of interleukin-2 (IL-2) and transforming growth factor-beta (TGF-ß) as a fuzzy structured model. Using the experimental data of murine models of B16F10 cell line of melanoma cancer cells, we optimized the parameters of the model. RESULTS: Using the output of this model, we determined the rules which could occur. As we optimized the parameters of the model using escape state of the tumor and then the rules which we obtained, are the rules of tumor escape. CONCLUSION: The results showed that using fuzzy structured agent-based model, we are able to show different output of the tumor-immune system interactions, which are caused by the stochastic behavior of each cell. But different output of the model just follow the predetermined behavior, and using this behavior, we can achieve the rules of interactions.

3.
Cancer Res ; 47(15): 4199-201, 1987 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-2440559

RESUMO

5-Azacytidine and several of its analogues are known to inhibit DNA methylation, alter gene expression, and inhibit cell growth. We report a Phase II study in which we investigated the antineoplastic activity of 5,6-dihydro-5-azacytidine and its induction of fetal hemoglobin synthesis when given by a 5-day continuous i.v. infusion of 1650 mg/m2/day that was repeated every 21 days. Fetal hemoglobin was measured in all patients; increased synthesis was found in 13 of the 17, in the absence of clinically significant anemia. Of the four patients who did not develop increased fetal hemoglobin, three had only one cycle of therapy. Fourteen patients with bronchogenic carcinoma were treated, and ten were evaluable for disease response. Five patients had disease stability of 2 or more mo, and five progressed on treatment. Three additional patients with mesothelioma were treated, and the two who were evaluable for disease response had stabilization of their disease. Fifteen of the 17 patients who received 5,6-dihydro-5-azacytidine developed a pleuritic-type chest pain, 12 had abnormal electrocardiograms, and four developed positive anti-nuclear antibodies. No significant hemopoietic, hepatic, or renal toxicities were observed. This study demonstrates that 5,6-dihydro-5-azacytidine in the dose and schedule used has no significant therapeutic activity in the treatment of lung cancer but does possess an unusual spectrum of clinical toxicities as well as the property of inducing fetal hemoglobin synthesis.


Assuntos
Azacitidina/análogos & derivados , Carcinoma Pulmonar de Células não Pequenas/genética , Hemoglobina Fetal/biossíntese , Regulação da Expressão Gênica/efeitos dos fármacos , Neoplasias Pulmonares/genética , Adulto , Anticorpos Antinucleares/análise , Azacitidina/efeitos adversos , Azacitidina/farmacologia , Azacitidina/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Avaliação de Medicamentos , Hemoglobina Fetal/genética , Globinas/genética , Cardiopatias/induzido quimicamente , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/metabolismo , Proteínas de Neoplasias/biossíntese , Proteínas de Neoplasias/genética , Dor/induzido quimicamente , Ativação Transcricional
4.
Biochim Biophys Acta ; 576(2): 466-70, 1979 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-427203

RESUMO

In a survey for abnormal haemoglobin variants in voluntary blood donors in Iran, a new variant was found in a young male who presented no clinical symptoms. It had the same electrophoretic mobility as haemoglobin D in alkaline buffers. Separation of the constituent polypeptide chains in acid urea buffer revealed it to be different from haemoglobin D previously found among Iranians. Analysis of its structure demonstrated a substitution to alanine (beta 47 Asp replaced by Ala) in the same residue as involved in haemoglobin G-Copenhagen (beta 47 Asp replaced by Asn).


Assuntos
Alanina , Ácido Aspártico , Hemoglobina A , Adulto , Sequência de Aminoácidos , Aminoácidos/análise , Humanos , Masculino , Fragmentos de Peptídeos/análise , Termolisina
5.
Biochim Biophys Acta ; 386(2): 525-9, 1975 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-1138883

RESUMO

A new haemoglobin variant (haemoglobin Arya), is described from an Iranian female. The substitution is at residue 47 (CD5) of the alpha chain in which aspartic acid has been substituted by asparagine. The presence of haemoglobin Arya was not associated with clinical symptoms. This variant has normal stability at 50 degrees C, but is slightly unstable when tested at 55 degrees C.


Assuntos
Hemoglobinas Anormais/análise , Aminoácidos/análise , Asparagina , Ácido Aspártico , Quimotripsina , Feminino , Humanos , Irã (Geográfico) , Pessoa de Meia-Idade , Fragmentos de Peptídeos/análise , Temperatura
6.
Biochim Biophys Acta ; 427(1): 119-25, 1976 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-1259994

RESUMO

Two new haemoglobins are described which were found during a regular survey on voluntary blood donors in Iran. They are haemoglobin Perspolis [alpha 64 (E13) Asp leads to Tyr] and haemoglobin J-Kurosh [alpha 19 (AB) Ala leads to Asp]. The amino acid substitution in these two variants was determined by fingerprinting and amino acid analysis of the tryptic peptides and thermolytic peptides derived from abnormal tryptic peptides. Neither haemoglobin was associated with clinical symptoms.


Assuntos
Hemoglobinas Anormais , Adulto , Alanina , Sequência de Aminoácidos , Aminoácidos/análise , Ácido Aspártico , Humanos , Irã (Geográfico) , Masculino , Tirosina
7.
J Mol Biol ; 201(2): 459-61, 1988 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-3418705

RESUMO

Haemoglobin North Chicago (ProC2(36 beta----Ser) has an abnormally high oxygen affinity. A survey of other abnormal human haemoglobins with high oxygen affinity has indicated that mutations leading to a cavity in the quaternary T-structure, or to the rupture of any bond in that structure, have raised oxygen affinities, because such mutations loosen the constraints of the T-structure. They do not usually affect the oxygen affinity of the R-structure. Haemoglobin North Chicago aroused our interest because the side-chain of serine is smaller than that of proline by only one carbon atom, and it was hard to conceive how such a small gap should raise the oxygen affinity significantly. Our X-ray study shows that the mutation produces unexpectedly large indirect changes in the T-structure.


Assuntos
Hemoglobinas Anormais/isolamento & purificação , Hemoglobinas/isolamento & purificação , Cristalização , Mutação , Difração de Raios X
8.
Gene ; 43(1-2): 23-8, 1986.
Artigo em Inglês | MEDLINE | ID: mdl-3758679

RESUMO

Three nonadecadeoxynucleotides complementary to the sense strand of the normal human beta-globin gene, beta A, and to the two allelic genes beta S and beta C were synthesized. The beta S and beta C globin genes both differ from the beta A gene by a single nucleotide substitution in the sequence coding for codon 6. The oligodeoxynucleotides are complementary to the genes in the region of the mutations and are therefore allele-specific. When radiolabeled and used as hybridization probes, the oligodeoxynucleotides are found to hybridize specifically to the mRNA transcribed from each allele.


Assuntos
Alelos , Genes , Globinas/genética , Transcrição Gênica , Humanos , Hibridização de Ácido Nucleico , Oligodesoxirribonucleotídeos/metabolismo
9.
Am J Clin Pathol ; 64(3): 416-20, 1975 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-1163493

RESUMO

During surveys for abnormal hemoglobins in Iran, an individual was found to have four electrophoretically distinct hemoglobins. The abnormality was found only in the father of the propositus, in two of the father's sisters, and in three brothers and sisters of the propositus. Investigations revealed that the four hemoglobin components are the result of a double heterozygosity between an alpha-chain variant (Hb OIndonesia) and a beta-chain variant (Hb DPunjab). The presence of the abnormal hemoglobins was not associated with hemolytic disorders or obvious clinical symptoms.


Assuntos
Hemoglobinopatias/genética , Hemoglobinas Anormais/análise , Eletroforese das Proteínas Sanguíneas , Fenômenos Químicos , Química , Criança , Heterozigoto , Humanos , Masculino , Linhagem , Fenótipo
10.
Regul Pept ; 102(2-3): 157-64, 2001 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-11730988

RESUMO

BACKGROUND AND AIM: Pituitary adenylate-cyclase activating peptide (PACAP) is a more potent proliferative agent than gastrin for rat enterochromaffin-like (ECL) cell proliferation in vitro. The role of this neurotransmitter during gastrin-mediated ECL cell tumor formation and gastrin-autonomous ECL cell neoplasia is unknown. METHODS AND RESULTS: ECL cell transformation was induced in the Mastomys using 16 wk H2 receptor blockade of acid inhibition. Examination of the epithelial fundic mucosa demonstrated that PACAP-immunoreactivity significantly increased in the tumor mucosa compared to the naïve stomach, and was associated with ECL cells. Naïve and tumor ECL cells were then purified (approximately 95%) from Mastomys and the presence of all three PACAP/VPAC receptor subtypes was demonstrated by polymerase chain-reaction amplification. Thereafter, cells were maintained in short-term (48 h) primary cultures. PACAP significantly (p<0.05) increased 24 h bromo-deoxyuridine uptake (approximately 4-fold) in both cell types with estimated EC(50) values of approximately 4x10(-16) M and approximately 2x10(-16) M, respectively. Specific receptor antagonists (PAC1/VPAC1) of PACAP competitively inhibited these proliferative effects in naïve cells. Oligonucleotide antisense directed against PAC1 significantly inhibited PACAP-stimulated DNA synthesis by approximately 85% (p<0.05) in tumor cells. CONCLUSION: PACAP is a potent and effective modulator of ECL cell proliferation. The expression of this neuropeptide and its receptors, particularly PAC1, suggest the existence of a neural regulatory pathway of ECL cell proliferation and transformation.


Assuntos
Transformação Celular Neoplásica/metabolismo , Celulas Tipo Enterocromafim/metabolismo , Celulas Tipo Enterocromafim/patologia , Muridae , Vias Neurais/efeitos dos fármacos , Neuropeptídeos/metabolismo , Animais , Divisão Celular/efeitos dos fármacos , Transformação Celular Neoplásica/efeitos dos fármacos , Transformação Celular Neoplásica/patologia , Células Cultivadas , DNA/biossíntese , Mucosa Gástrica/efeitos dos fármacos , Mucosa Gástrica/inervação , Mucosa Gástrica/metabolismo , Mucosa Gástrica/patologia , Humanos , Microscopia de Fluorescência , Neuropeptídeos/imunologia , Neuropeptídeos/farmacologia , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores de Polipeptídeo Hipofisário Ativador de Adenilato Ciclase , Receptores de Polipeptídeo Hipofisário Ativador de Adenilato Ciclase , Receptores do Hormônio Hipofisário/antagonistas & inibidores , Receptores do Hormônio Hipofisário/genética , Receptores do Hormônio Hipofisário/metabolismo , Receptores Tipo I de Polipeptídeo Intestinal Vasoativo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia , Células Tumorais Cultivadas
11.
Clin Chim Acta ; 287(1-2): 123-30, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10509901

RESUMO

Advanced glycation endproducts (AGEs) have been implicated as a major pathogenic process in leading to diabetic complications. An increasing number of drug candidates have recently been developed as potential inhibitors of AGEs. Aminoguanidine, a hydrazine-like molecule is the first drug that was extensively studied both in vitro and in vivo as an inhibitor of AGE formation. Several assay methods have been proposed to determine the inhibitory effect of glycation inhibitors, including assays based on inhibition of specific fluorescence generated in the course of glycation and AGE-formation; assays based on the inhibition of AGE-protein crosslinks, and dimer and trimer formation; and specific ELISA assays using anti-AGE antibodies for quantitative measurement of AGEs in the presence and absence of the inhibitor. However, none of these assays can accurately evaluate chemical intermediates and products generated during the early stages of glycation. We have devised a new rapid assay method for evaluation of the early stage of glycation (Amadori product). This assay is based on the interaction of delta-gluconolactone (delta-Glu), an oxidized (ketoaldehyde) analogue of glucose, with hemoglobin present in blood samples. The assay involves determination of the percentage of glycated hemoglobin (HbA1C) after incubation at 37 degrees for 16 h with delta-Glu (50 mmol/L) using a dedicated ion-exchange high-performance liquid chromatography (HPLC) system. The results using normal human red blood cells show HbA1C levels to be 180% higher than baseline controls. The effects of various inhibitors are determined by measuring the levels of HbA1C by the compound in question compared to delta-Glu-treated vehicle only blood samples. This new assay provides a relevant and physiological model to study glycation and potential inhibitors. Furthermore, it offers a means to differentiate between inhibitors of the early and late stages of glycation and provides a rapid method of screening large numbers of potential inhibitors of glycation. Contrary to the assay methods, which are based on the measurement of fluorescence of fluorophores generated during glycation, the proposed assay does not suffer from the possible problem of overlapping and interference of AGE-specific fluorescence with the intrinsic fluorescence of the inhibitor compound.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Cromatografia por Troca Iônica/métodos , Gluconatos/metabolismo , Hemoglobinas Glicadas/metabolismo , Produtos Finais de Glicação Avançada , Humanos , Lactonas , Espectrometria de Fluorescência
12.
Clin Chim Acta ; 301(1-2): 65-77, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11020463

RESUMO

Enhanced formation and accumulation of advanced glycation end products (AGEs) have been proposed to play a major role in the pathogenesis of diabetic complications, and atherosclerosis, leading to the development of a range of diabetic complications including nephropathy, retinopathy and neuropathy. Several potential drug candidates as AGE inhibitors have been reported recently. Aminoguanidine is the first drug extensively studied. However, there are no currently available medications known to block AGE formation. We have previously reported a number of novel and structurally diverse compounds as potent inhibitors of glycation and AGE formation. We have now studied several of the existing drugs, which are in therapeutic practice for lowering blood sugar or the treatment of peripheral vascular disease in diabetic patients, for possible inhibitory effects on glycation. We show that that three compounds; pioglitazone, metformin and pentoxifylline are also inhibitors of glycation.


Assuntos
Produtos Finais de Glicação Avançada/antagonistas & inibidores , Hipoglicemiantes/farmacologia , Metformina/farmacologia , Pentoxifilina/farmacologia , Tiazóis/farmacologia , Tiazolidinedionas , Ensaio de Imunoadsorção Enzimática , Hemoglobinas Glicadas/análise , Humanos , Pioglitazona
13.
Acta Med Iran ; 20(1-2): 1-8, 1977.
Artigo em Inglês | MEDLINE | ID: mdl-614769

RESUMO

Haemoglobin MBoston is described in a 19 year old Iranian male, his father and three out of his five brothers and sisters which were cyanotic from the birth. The presence of haemoglobin M was established after starch-gel electrophoresis of the ferricyanide treated haemolysate at pH 7.1 and by spectroscopic examination of the purified abnormal haemoglobin at pH 6.5.


Assuntos
Hemoglobina M , Hemoglobinas Anormais , Metemoglobinemia/genética , Adulto , Cianose/etiologia , Eletroforese em Gel de Amido , Humanos , Irã (Geográfico) , Masculino
14.
Acta Med Iran ; 21(1): 39-46, 1978.
Artigo em Inglês | MEDLINE | ID: mdl-110036

RESUMO

Waldenstrom's macroglobulinemia was studied in a 46 year old Iranian male with anemia, bleeding, ecchymose and splenomegaly. The diagnosis of Macroglobulinemia was established by the presence of very high level of IgM paraprotein in sera which was detectable by immunoelectrophoresis and rocket immunoelectrophoresis, and by the presence of bone marrow infiltration of plasmocytes. Family studies revealed a high IgM level in one of the patient's daughters.


Assuntos
Macroglobulinemia de Waldenstrom/imunologia , Biópsia , Proteínas Sanguíneas/análise , Medula Óssea/patologia , Feminino , Humanos , Imunoeletroforese , Imunoglobulina M/análise , Masculino , Pessoa de Meia-Idade , Macroglobulinemia de Waldenstrom/diagnóstico , Macroglobulinemia de Waldenstrom/metabolismo
15.
Br J Pharmacol ; 171(12): 3103-14, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24611770

RESUMO

BACKGROUND AND PURPOSE: We determined the effects of treatment with LR-90, an inhibitor of advanced glycation end products, on the mechanical properties of the arterial system in streptozotocin (STZ)-induced diabetic Sprague Dawley rats, using aortic impedance analysis, and further investigated the effects of LR-90 on the progression of aortic pathology. EXPERIMENTAL APPROACH: STZ-induced diabetic rats were treated with or without LR-90 (50 mg L(-1) in drinking water) for 8 weeks and compared with control groups. Arterial BP measurements, various metabolic parameters, aortic histopathology, collagen cross-linking, AGE accumulation, and RAGE protein expression in aortic tissue were determined. Pulsatile parameters were evaluated using a standard Fourier series expansion technique and impulse response function of the filtered aortic input impedance spectra. KEY RESULTS: LR-90 reduced glycated haemoglobin and triglycerides levels, although it had no effect on the glycaemic status. LR-90 did not affect arterial BP, but prevented the diabetes-induced increase in peripheral resistance and variations in aortic distensibility, as it reduced aortic characteristic impedance by 21%. LR-90 also prevented the elevation in wave reflection factor, as indicated by a 22.5% reduction and an associated increase of 23.5% in wave transit time, suggesting it prevents the augmentation of the systolic load of the left ventricle. Moreover, LR-90 inhibited collagen cross-linking and the accumulation of AGE and RAGE in the vasculature of diabetic rats. CONCLUSIONS AND IMPLICATIONS: Treatment with LR-90 may impart significant protection against diabetes-induced aortic stiffening and cardiac hypertrophy and provides an additional therapeutic option for treatment of AGE associated diabetic complications.


Assuntos
Aorta/efeitos dos fármacos , Butiratos/farmacologia , Diabetes Mellitus Experimental/tratamento farmacológico , Angiopatias Diabéticas/prevenção & controle , Produtos Finais de Glicação Avançada/antagonistas & inibidores , Hipoglicemiantes/farmacologia , Rigidez Vascular/efeitos dos fármacos , Animais , Aorta/metabolismo , Aorta/patologia , Aorta/fisiopatologia , Pressão Sanguínea/efeitos dos fármacos , Cardiomegalia/sangue , Cardiomegalia/fisiopatologia , Cardiomegalia/prevenção & controle , Colágeno/metabolismo , Complacência (Medida de Distensibilidade) , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/patologia , Diabetes Mellitus Experimental/fisiopatologia , Angiopatias Diabéticas/sangue , Angiopatias Diabéticas/patologia , Angiopatias Diabéticas/fisiopatologia , Hemoglobinas Glicadas/metabolismo , Produtos Finais de Glicação Avançada/metabolismo , Masculino , Ratos Sprague-Dawley , Receptor para Produtos Finais de Glicação Avançada , Receptores Imunológicos/efeitos dos fármacos , Receptores Imunológicos/metabolismo , Fatores de Tempo , Triglicerídeos/sangue , Resistência Vascular/efeitos dos fármacos
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