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1.
Clin Exp Obstet Gynecol ; 43(1): 16-24, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27048012

RESUMO

OBJECTIVE: To demonstrate that the use of 3D/4D HDLive increases the image quality in the diagnosis of benign cystic ovarian teratomas. MATERIALS AND METHODS: 3D/HDLive ultrasound (US) was used in 31 cases of suspected ovarian cystic teratoma using vaginal 2D US. The following pathognomonic images of mature cystic teratomas were considered for diagnosis: 1) a cystic, unilocular lesion with a densely echogenic tubercle (Rokitansky nodule); 2) a diffuse or partially echogenic mass usually demonstrating sound attenuation; 3) fluid-fluid/fat-fluid levels; 4) dermoid mesh with hyperechogenic calcifications indicating the presence of bone, teeth, or other ectodermally-derived structure; 5) multiple mobile spherical structures (fat globules). RESULTS: Dermoids present a wide spectrum of images depending on the predominant tissue type. In the vast majority of cases there are dense echogenic structures that correspond to complex masses of fatty tissue, sebum, hair, epithelial remnants, along with cartilage or bone. If we catalogue all the images together, the pathognomonic of dermoid are: 1) cystic or solid cystic lesions with a Rokitansky nodule, with bone, teeth or cartilage (six cases, 22.2%); 2) a solid mass with or without attenuation that corresponds with pure sebum (five cases, 18.5%); 3) a diffuse mass with fine bands that correspond with hair inside sebum (four cases, 12.9%) and that may form meshes or plugs corresponding with a mixture of fat, sebum, and hair (three cases, 11.5%). CONCLUSIONS: HDLive U.S. provides some images of exceptional quality that enhance the definition of the structures of these tumors (fat, hair, cartilage, bone, etc.) compared to 2D/3D/4D.


Assuntos
Cisto Dermoide/diagnóstico por imagem , Imageamento Tridimensional/métodos , Neoplasias Ovarianas/diagnóstico por imagem , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Diagnóstico Diferencial , Feminino , Humanos , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Ultrassonografia , Adulto Jovem
2.
Int J Clin Pharm ; 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38990457

RESUMO

BACKGROUND: Monoclonal antibodies targeting calcitonin gene-related peptide (anti-CGRP mAbs) have shown clinical effectiveness and safety in randomized clinical studies. However, long-term studies in clinical practice remain limited. AIM: To assess the long-term effectiveness, clinical predictors and safety of three anti-CGRP mAbs (erenumab, galcanezumab, fremanezumab) in resistant migraine patients. METHOD: A single-center retrospective study was conducted from December 2019 to June 2023 involving 120 resistant migraine patients who received at least a month of anti-CGRP mAbs treatment. Patients completed a headache diary that included monthly acute medication intake (MAM), monthly migraine days (MMD), adverse events as well as completed Patient-Reported Outcome questionnaires (MIDAS [Migraine Disability Assessment] and Headache Impact Test 6 [HIT-6]). The number of patients achieving a ≥ 50% reduction in monthly migraine days was determined and classified as ≥ 50% responders, and baseline parameters and logistic regression between responders and non-responders were analyzed to identify potential predictors of response. Adverse events were registered in every follow-up. RESULTS: Treatment with anti-CGRP mAbs led to reductions in MIDAS, HIT-6, MMD and MAM from baseline to 6-24 months. At 6-12 months, responders (61% and 57%, respectively) exhibited lower baseline MMD and MAM. Medication overuse  was associated with non-responders from 6 to 24 months and it was identified as a negative predictor of treatment effectiveness (OR 0.23, 95% CI 0.07-0.74; p = 0.014). CONCLUSION: Anti-CGRP mAbs prove effectiveness and safety over a 24-month period in a RM population. Patients with no medication overuse and lower basal MMDs and MAM may respond better to anti-CGRP mAbs.

3.
Clin Exp Obstet Gynecol ; 40(4): 505-9, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24597244

RESUMO

A prospective study of 63 singleton pregnancies between 11 + 0 and 13 + 6 weeks gestation underwent semi-automatic nuchal translucency (NT) measurement and were compared with two-dimensional ultrasonography (2D US). Inter-observer variation and the repeatability were evaluated. Sono T automatically achieves mid-sagittal plane views and measures the maximum NT thickness. Measurements have less inter-observer variation (CI = -0.13, -0.04) when compared with 2D measurements (CI = -0.45, 0.28). It is reproducible and comparable to conventional 2D US technique for NT measurement. However, incorporating Sono T into routine practice requires further program refinements in order to reduce erroneous NT measurements.


Assuntos
Medição da Translucência Nucal/métodos , Feminino , Idade Gestacional , Humanos , Variações Dependentes do Observador , Gravidez , Estudos Prospectivos
4.
Proc Natl Acad Sci U S A ; 106(39): 16752-7, 2009 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-19805368

RESUMO

Cell surface proteins are excellent targets for diagnostic and therapeutic interventions. By using bioinformatics tools, we generated a catalog of 3,702 transmembrane proteins located at the surface of human cells (human cell surfaceome). We explored the genetic diversity of the human cell surfaceome at different levels, including the distribution of polymorphisms, conservation among eukaryotic species, and patterns of gene expression. By integrating expression information from a variety of sources, we were able to identify surfaceome genes with a restricted expression in normal tissues and/or differential expression in tumors, important characteristics for putative tumor targets. A high-throughput and efficient quantitative real-time PCR approach was used to validate 593 surfaceome genes selected on the basis of their expression pattern in normal and tumor samples. A number of candidates were identified as potential diagnostic and therapeutic targets for colorectal tumors and glioblastoma. Several candidate genes were also identified as coding for cell surface cancer/testis antigens. The human cell surfaceome will serve as a reference for further studies aimed at characterizing tumor targets at the surface of human cells.


Assuntos
Biologia Computacional , Proteínas de Membrana/genética , Antígenos de Superfície/genética , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Linhagem Celular Tumoral , Neoplasias Colorretais/genética , Bases de Dados Genéticas , Epigênese Genética , Variação Genética , Glioblastoma/genética , Humanos , Proteínas de Membrana/metabolismo
5.
Clin Exp Obstet Gynecol ; 39(1): 13-8, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22675946

RESUMO

PURPOSE OF INVESTIGATION: The main objective of our prospective, observational, analytical research work was to determine whether Anti-Müllerian hormone (AMH) and antral follicle count (AFC) could be effectively used as predictors of ovarian reserve and, possibly, of reproductive outcome with ART. METHODS: We studied 143 IVF/ET cycles in patients with a previous history of ART failure, all of them supposed to be of poor prognosis, who had agreed to another ART attempt after knowing their AMH, AFC, and base hormone (FSH, LH, 17 beta-estradiol) levels. RESULTS: AMH and AFC showed a positive correlation with the number of oocytes retrieved (p = 0.0016) and (p < 0.0001), respectively and with percentage of MII oocytes, (p = 0.00756) and (p < 0.001). The combined use of these markers showed an area under the curve of 82.2% for oocytes retrieved. Our results shows a very high cancelation (22% of started cycles) and very low pregnancy rates (6.7% and 9.8%) in low and normoresponders, respectively. CONCLUSIONS: AMH levels and AFC are reliable indicators of ovarian reserve. Patients with ovarian reserve levels that predict a very low probability of success should be informed that the poor prognosis associated with these values may not justify the expense of IVF/ET.


Assuntos
Hormônio Antimülleriano/sangue , Ovário/citologia , Adulto , Biomarcadores/sangue , Estradiol/sangue , Feminino , Hormônio Foliculoestimulante/sangue , Humanos , Imageamento Tridimensional , Hormônio Luteinizante/sangue , Ovário/diagnóstico por imagem , Ovário/fisiologia , Gravidez , Taxa de Gravidez , Estudos Prospectivos , Técnicas de Reprodução Assistida , Falha de Tratamento , Ultrassonografia
6.
Science ; 287(5460): 2017-9, 2000 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-10720328

RESUMO

Examination of human bladder, head and neck, and lung primary tumors revealed a high frequency of mitochondrial DNA (mtDNA) mutations. The majority of these somatic mutations were homoplasmic in nature, indicating that the mutant mtDNA became dominant in tumor cells. The mutated mtDNA was readily detectable in paired bodily fluids from each type of cancer and was 19 to 220 times as abundant as mutated nuclear p53 DNA. By virtue of their clonal nature and high copy number, mitochondrial mutations may provide a powerful molecular marker for noninvasive detection of cancer.


Assuntos
Líquidos Corporais/química , DNA Mitocondrial/genética , DNA de Neoplasias/genética , Mutação , Neoplasias/genética , Substituição de Aminoácidos , Líquido da Lavagem Broncoalveolar/química , DNA Mitocondrial/análise , DNA Mitocondrial/urina , DNA de Neoplasias/análise , DNA de Neoplasias/urina , Genes p53 , Neoplasias de Cabeça e Pescoço/diagnóstico , Neoplasias de Cabeça e Pescoço/genética , Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/genética , Neoplasias/diagnóstico , Mutação Puntual , Reação em Cadeia da Polimerase , Polimorfismo Genético , Saliva/química , Deleção de Sequência , Neoplasias da Bexiga Urinária/diagnóstico , Neoplasias da Bexiga Urinária/genética
7.
Phys Rev E Stat Nonlin Soft Matter Phys ; 79(2 Pt 2): 026103, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19391802

RESUMO

Recently, crust cooling times have been measured for neutron stars after extended outbursts. These observations are very sensitive to the thermal conductivity kappa of the crust and strongly suggest that kappa is large. We perform molecular dynamics simulations of the structure of the crust of an accreting neutron star using a complex composition that includes many impurities. The composition comes from simulations of rapid proton capture nucleosynthesis followed by electron captures. We find that the thermal conductivity is reduced by impurity scattering. In addition, we find phase separation. Some impurities with low atomic number Z are concentrated in a subregion of the simulation volume. For our composition, the solid crust must separate into regions of different compositions. This could lead to an asymmetric star with a quadrupole deformation. Observations of crust cooling can constrain impurity concentrations.

8.
Braz J Med Biol Res ; 39(8): 1101-13, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16906285

RESUMO

Clinical stage (CS) is an established indicator of breast cancer outcome. In the present study, a cDNA microarray platform containing 692 genes was used to identify molecular differences between CSII and CSIII disease. Tumor samples were collected from patients with CSII or CSIII breast cancer, and normal breast tissue was collected from women without invasive cancer. Seventy-eight genes were deregulated in CSIII tumors and 22 in CSII tumors when compared to normal tissue, and 20 of them were differentially expressed in both CSII and CSIII tumors. In addition, 58 genes were specifically altered in CSIII and expression of 6 of them was tested by real time RT-PCR in another cohort of patients with CSII or CSIII breast cancer and in women without cancer. Among these genes, MAX, KRT15 and S100A14, but not APOBEC3G or KRT19, were differentially expressed on both CSIII and CSII tumors as compared to normal tissue. Increased HMOX1 levels were detected only in CSIII tumors and may represent a molecular marker of this stage. A clear difference in gene expression pattern occurs at the normal-to-cancer transition; however, most of the differentially expressed genes are deregulated in tumors of both CS (II and III) compared to normal breast tissue.


Assuntos
Neoplasias da Mama/genética , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica/genética , Adulto , Idoso , Antibióticos Antineoplásicos/uso terapêutico , Sequência de Bases , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Doxorrubicina/uso terapêutico , Feminino , Humanos , Pessoa de Meia-Idade , Dados de Sequência Molecular , Estadiamento de Neoplasias , Análise de Sequência com Séries de Oligonucleotídeos , Estudos Prospectivos , Reação em Cadeia da Polimerase Via Transcriptase Reversa
9.
Cancer Res ; 60(19): 5529-35, 2000 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-11034098

RESUMO

Genetic alterations of chromosome 7 are common in human cancer. Furthermore, previous studies have supported the presence of a gene important in a broad range of cancers at 7q22-31.1. There is evidence that supports an oncogenic function for this putative gene, as well as evidence that supports a tumor suppressive role. In this study, we used a cross-species candidate gene approach in combination with physical mapping to identify MPP11 as a candidate for the putative cancer-related activity at 7q22-31.1. We then analyzed primary head and neck squamous cell tumors (HNSCCs) for loss of heterozygosity/allelic imbalance (LOH/AI) at the MPP11 genomic locus. Thirty-eight percent of tumors examined displayed LOH/AI involving the MPP11 genomic locus. Mutation analysis of MPP11 in the latter samples did not identify any inactivating mutations. However, immunohistochemical staining of primary tumor sections and Western blot analysis of HNSCC cell lines revealed a tumor-specific high level of expression of MPP11p. Fluorescence in situ hybridization analysis done on the cell lines identified increased chromosome 7 copy number with a concomitant increase in MPP11 copy number. These results suggest an oncogenic role for MPP11 in HNSCC.


Assuntos
Carcinoma de Células Escamosas/genética , Proteínas de Ligação a DNA/genética , Neoplasias de Cabeça e Pescoço/genética , Proteínas Oncogênicas , Proteínas de Saccharomyces cerevisiae , Alelos , Sequência de Aminoácidos , Animais , Carcinoma de Células Escamosas/metabolismo , Bovinos , Mapeamento Cromossômico , Cromossomos Humanos Par 7 , DNA de Neoplasias/genética , Proteínas de Ligação a DNA/biossíntese , Proteínas Fúngicas/genética , Dosagem de Genes , Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Inativação Gênica , Neoplasias de Cabeça e Pescoço/metabolismo , Humanos , Hibridização in Situ Fluorescente , Perda de Heterozigosidade , Repetições de Microssatélites , Chaperonas Moleculares , Dados de Sequência Molecular , Proteínas de Ligação a RNA , Homologia de Sequência de Aminoácidos
10.
Oncogene ; 20(37): 5195-8, 2001 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-11526508

RESUMO

We recently demonstrated the existence of specific patterns of somatic mitochondrial DNA (mtDNA) mutations in several cancers. Here we sought to identify the presence of mtDNA mutations in prostate cancer and their paired PIN lesions. The D-loop region, 16S rRNA, and the NADH subunits of complex I were sequenced to identify mtDNA mutations in 16 matched PIN lesions and primary prostate cancers. Twenty mtDNA mutations were detected in the tumor tissue of three patients. Identical mutations were also identified in the PIN lesion from one patient. This patient with multiple point mutations also harbored a high frequency of microsatellite instability (MSI-H) in nuclear mononucleotide repeat markers. Remarkably, identical mutations were also detected in all (3/3) matched urine and plasma samples obtained from these patients. Although mitochondrial mutations are less common in prostate adenocarcinoma, they occur early in cancer progression and they can be detected in bodily fluids of early stage disease patients. The identification of MtDNA mutations may complement other early detection approaches for prostate cancer.


Assuntos
DNA Mitocondrial/metabolismo , Mitocôndrias/metabolismo , Mutação , Neoplasias da Próstata/sangue , Neoplasias da Próstata/genética , Neoplasias da Próstata/urina , RNA Ribossômico 16S/metabolismo , Adenocarcinoma/sangue , Adenocarcinoma/genética , Adenocarcinoma/urina , Humanos , Masculino , Repetições de Microssatélites , NADH Desidrogenase/metabolismo , Mutação Puntual , Análise de Sequência de DNA
11.
Trends Mol Med ; 7(2): 76-80, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11286759

RESUMO

Microsatellite instability (MSI) is a common feature of gastric cancers that reflects underlying mismatch-repair deficiency in the tumor, caused most frequently by methylation of the hMLH1 promoter. Tumors with MSI have been found to inactivate certain target genes by permitting an increased frequency of mutations in mononucleotide runs in their coding regions. Gastric tumors with MSI have a distinct clinicopathological profile with a relatively good prognosis. Using the simple and robust methodologies available, MSI detection in gastrointestinal tumors promises to be one of the first widely used molecular prognostic tests for human cancer. Here, we review the molecular context of this exciting prospect with respect to one of the world's most prevalent cancers, that of the stomach.


Assuntos
Repetições de Microssatélites , Proteínas de Neoplasias/genética , Neoplasias Gástricas/classificação , Neoplasias Gástricas/genética , Proteínas Adaptadoras de Transdução de Sinal , Pareamento Incorreto de Bases , Proteínas de Transporte , Reparo do DNA , Saúde da Família , Neoplasias Gastrointestinais/genética , Humanos , Proteína 1 Homóloga a MutL , Proteínas Nucleares , Prognóstico , Regiões Promotoras Genéticas , Expansão das Repetições de Trinucleotídeos
12.
Transplantation ; 71(3): 412-7, 2001 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-11233903

RESUMO

BACKGROUND: Antigenemia and quantitative polymerase chain reaction (PCR) are widely used for cytomegalovirus (CMV) diagnosis after heart transplantation due to their enhanced predictive values for disease detection when specific cut-off values are used. The purpose of this study was to compare, in the same patient setting, the predictive values of quantitative PCR and antigenemia for CMV disease detection, using specific cut-off values. METHODS: Thirty heart transplant receptors were ch prospectively monitored for active CMV infection and disease detection, using quantitative PCR and anti- po genemia. Positive and negative predictive values for pr CMV disease detection were calculated using cut-off pr values for both antigenemia (5 and 10 positive cells/300,000 neutrophils) and quantitative-PCR (50,000 and 100,000 copies/10(6) leukocytes). RESULTS: Active CMV infection was diagnosed in 93.3% of patients and CMV disease in 23.3%. The positive and negative predictive (%) values for CMV disease detection were 35/100 and 46.7/100, respectively, for quantitative PCR and antigenemia. Using 5 and 10 positive cells/300,000 neutrophils as cut-off values for antigenemia, the positive and negative predictive values (%) for disease detection were respectively 63.6/100 and 70/100. For quantitative PCR, the positive and th negative predictive values (%) for cut-off values of to 50,000 and 100,000 copies/10(6) leukocytes were 53.8/100 and 60/94.1, respectively. CONCLUSION: In our series, antigenemia and quantitative-PCR had enhanced and similar predictive values for CMV disease detection when specific cut-off values were used. The choice between these two methods for disease detection may rely less on their efficiency and more on the experience and familiarity with them.


Assuntos
Antígenos Virais/sangue , Infecções por Citomegalovirus/diagnóstico , Citomegalovirus/imunologia , Transplante de Coração/efeitos adversos , Reação em Cadeia da Polimerase/métodos , Adolescente , Adulto , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Tempo
13.
Invest Ophthalmol Vis Sci ; 42(8): 1679-84, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11431428

RESUMO

PURPOSE: Genetic abnormalities of chromosomal arm 8q have been reported by many studies in uveal melanoma. To better understand the role of 8q abnormalities in uveal melanoma development, copy number anomalies of the c-myc oncogene (located on 8q24.1) have been investigated. METHODS: Forty-three uveal melanomas were analyzed by fluorescent in situ hybridization (FISH) with probes for c-myc and the chromosome 8 centromere. Results of the FISH analysis were compared with genetic changes previously detected by microsatellite analysis on chromosomes 3 and 6p. RESULTS: Thirty uveal melanomas (70%) had extra copies of c-myc, 2 tumors (5%) had loss of c-myc, and 11 tumors (25%) had no abnormalities in c-myc copy number. Of those with extra copies of c-myc, 13 tumors (43%) had amplification of the c-myc gene, 14 tumors (47%) had an intermediate relative increase in the c-myc copy number, and 3 tumors (10%) had a simple gain of chromosome 8. An association between larger tumor size and c-myc amplification was found (P < 0.01). Although extra copies of c-myc were seen in tumors with retention of chromosome 3, remarkably only tumors with monosomy 3 showed amplification of c-myc (P = 0.03). CONCLUSIONS: The specific amplification of the c-myc oncogene detected in at least 30% of primary uveal melanomas cannot be explained by the simple 8q abnormalities observed in cytogenetic studies. The striking association between c-myc amplification and monosomy 3 suggests a unique pathway of genetic progression in a subset of uveal melanomas.


Assuntos
Aberrações Cromossômicas/genética , Cromossomos Humanos Par 8/genética , Dosagem de Genes , Genes myc/genética , Melanoma/genética , Neoplasias Uveais/genética , Transtornos Cromossômicos , Cromossomos Humanos Par 3/genética , Cromossomos Humanos Par 6/genética , DNA de Neoplasias/análise , Amplificação de Genes , Humanos , Hibridização in Situ Fluorescente , Melanoma/patologia , Repetições de Microssatélites/genética , Neoplasias Uveais/patologia
14.
Cancer Lett ; 172(1): 67-73, 2001 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-11595131

RESUMO

The human oligophrenin-1 gene is ubiquitously expressed at low levels and expressed at high levels in the developing neuroepithelium of the neural tube. Mutations in this gene have been related to the X-linked mental retardation. Using cDNA microarrays, we found evidence that oligophrenin-1 is strongly up-regulated in colorectal tumors. Semiquantitative reverse transcriptase polymerase chain reaction confirmed this finding. Thus, a well-known nervous system-associated human gene transcript may also be an important colorectal tumor marker and potential therapeutic target.


Assuntos
Neoplasias Colorretais/metabolismo , Proteínas do Citoesqueleto , DNA Complementar/metabolismo , Proteínas Ativadoras de GTPase , Proteínas Nucleares/biossíntese , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Fosfoproteínas/biossíntese , Biomarcadores Tumorais , Humanos , Mutação , Proteínas Nucleares/genética , Fosfoproteínas/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Regulação para Cima
15.
Cancer Lett ; 170(1): 73-9, 2001 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-11448537

RESUMO

PGP 9.5 is a neurospecific peptide that functions to remove ubiquitin from ubiquitinated cellular proteins, thereby preventing them from targeted degradation by the proteasome-dependent pathway or regulating their localization, activity or structure. Using the serial analysis of gene expression method (SAGE), we initially found that the PGP9.5 transcript and protein was highly expressed in more than 50% of primary lung cancers and nearly all lung cancer cell lines but was not detectable in the normal lung. This increased expression could be the result of transcriptional regulation accompanied by methylation changes at the CpG island of the promoter region. We studied the methylation status of the cytosines at the promoter region of human PGP9.5 using sodium bisulfite genomic sequencing in normal and neoplastic cells. Although no methylation of PGP9.5 promoter was observed in the normal lung, normal cervical tissue, and lung cancer cell lines, this region was densely methylated in the HeLa cell line. Exposure to HeLa cells to the demethylating agent, 5-aza-2'-deoxycytidine, led to re-expression of PGP9.5. This data suggested that while other mechanisms may be involved in the frequent overexpression of PGP9.5 gene in lung tumors and lung cancer cell lines, promoter methylation may play a role in the transcriptional suppression of PGP9.5 gene expression in the cervical tissue-derived HeLa cell line.


Assuntos
Metilação de DNA , Neoplasias Pulmonares/genética , Tioléster Hidrolases/genética , Sequência de Bases , DNA de Neoplasias , Células HeLa , Humanos , Dados de Sequência Molecular , Regiões Promotoras Genéticas , Células Tumorais Cultivadas , Ubiquitina Tiolesterase
16.
EXS ; 67: 331-7, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8400703

RESUMO

There is a lack of sequence information concerning polymorphic loci in parasite genomes. Thus, the use of arbitrary PCR primers under low temperature annealing conditions to generate random amplified polymorphic DNAs (RAPDs) represents an important approach to the study of the structure of parasite populations, their genetic variation as well as improved diagnosis of the diseases they cause. Following the examination of all variables and their effect on the reproducibility of the reaction, we have established a protocol for the analysis of RAPDs that involves amplification at two separate DNA concentrations followed by polyacrylamide gel electrophoresis and silver staining. We find the technique to be sensitive, reproducible, simple and relatively cheap. It has already provided insight into the genetic variation in populations of schistosomes and trypanosomes and is being used to study various other endemic infections. We also use specific primers under low stringency conditions in situations where the objective of the amplification is the detection of a particular sequence and where normal high stringency conditions give a positive/negative answer such as sex determination or diagnosis of blood born infections. Under low stringency conditions, specific amplification products persist but products of low stringency priming are also apparent and serve as a perfect internal control for negative samples.


Assuntos
Impressões Digitais de DNA/métodos , Schistosoma mansoni/genética , Trypanosoma cruzi/genética , Animais , Sequência de Bases , Impressões Digitais de DNA/estatística & dados numéricos , Primers do DNA/genética , DNA de Protozoário/genética , Feminino , Marcadores Genéticos , Masculino , Dados de Sequência Molecular , Polimorfismo Genético , Análise para Determinação do Sexo/métodos
17.
Dis Markers ; 17(2): 67-75, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11673653

RESUMO

Eukaryotic mRNAs are transcribed as precursors containing their intronic sequences. These are subsequently excised and the exons are spliced together to form mature mRNAs. This process can lead to transcript diversification through the phenomenon of alternative splicing. Alternative splicing can take the form of one or more skipped exons, variable position of intron splicing or intron retention. The effect of alternative splicing in expanding protein repertoire might partially underlie the apparent discrepancy between gene number and the complexity of higher eukaryotes. It is likely that more than 50% form. Many cancer-associated genes, such as CD44 and WT1 are alternatively spliced. Variation of the splicing process occurs during tumor progression and may play a major role in tumorigenesis. Furthermore, alternatively spliced transcripts may be extremely useful as cancer markers, since it appears likely that there may be striking contrasts in usage of alternatively spliced transcript variants between normal and tumor tissue than in alterations in the general levels of gene expression.


Assuntos
Processamento Alternativo , Biomarcadores Tumorais/genética , RNA Mensageiro/genética , Humanos , Receptores de Hialuronatos/genética , Proteínas WT1/genética
18.
J Clin Pathol ; 56(1): 52-5, 2003 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12499435

RESUMO

BACKGROUND: Alterations in the methylation patterns of promoter CpG islands have been associated with the transcriptional inhibition of genes in many human cancers. These epigenetic alterations could be used as molecular markers for the early detection of cancer-that is, while potentially curable according to current therapeutic strategies. In prostate cancer, GSTP1 hypermethylation is the most common epigenetic alteration, and can be detected in up to 90% of cases. Thus, screening for methylation of other loci would probably increase the number of primary tumours amenable to screening. Moreover, previous studies have shown that the endothelin B receptor (EDNRB) gene is abnormally methylated in a high proportion of prostate tumours ( approximately 70%). AIMS: To investigate the potential use of EDNRB gene hypermethylation as a prostate cancer specific marker. METHODS: Methylation specific polymerase chain reaction (MSP) for the promoter region of EDNRB was performed on prospectively collected tissue samples from 48 patients harbouring clinically localised prostate cancer, and in a group of 23 patients with benign prostatic hyperplasia (BPH). Genomic DNA was isolated from the samples and the methylation status was examined in a blinded manner. RESULTS: EDNRB methylation was found in 40 of 48 of the adenocarcinomas. However, the same alteration was found in the paired normal tissue, and 21 of 23 of the BPH samples were found to harbour EDNRB hypermethylation. CONCLUSIONS: EDNRB hypermethylation at CpG sites upstream of the transcription start site can be detected in a high proportion of prostate adenocarcinomas. However, because this same alteration is also present in normal and hyperplastic tissue, it does not distinguish normal from neoplastic prostate cells, thus precluding its use as a prostate cancer marker.


Assuntos
Adenocarcinoma/genética , Metilação de DNA , Proteínas de Neoplasias/genética , Neoplasias da Próstata/genética , Receptores de Endotelina/genética , Idoso , Ilhas de CpG/genética , DNA de Neoplasias/genética , Marcadores Genéticos , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase/métodos , Estudos Prospectivos , Hiperplasia Prostática/genética , Receptor de Endotelina B
19.
Diagn Microbiol Infect Dis ; 22(4): 343-8, 1995 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8582141

RESUMO

A 285-bp DNA fragment was amplified using the polymerase chain reaction from 38 Leptospira serovars of six different genomic species. The fragments amplified exhibited differential mobilities on nondenaturing polyacrylamide gels resulting from sequence-dependent conformational alterations. Leptospira interrogans serovars could be distinguished from those of other species on this basis.


Assuntos
DNA Bacteriano/análise , Leptospira interrogans , Reação em Cadeia da Polimerase , Doença de Weil/diagnóstico , Técnicas de Tipagem Bacteriana , Sequência de Bases , Diagnóstico Diferencial , Eletroforese em Gel de Poliacrilamida , Humanos , Leptospira interrogans/classificação , Leptospira interrogans/genética , Dados de Sequência Molecular , Sensibilidade e Especificidade , Coloração pela Prata
20.
Braz J Med Biol Res ; 32(12): 1515-23, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10585633

RESUMO

To assess the clinical relevance of a semi-quantitative measurement of human cytomegalovirus (HCMV) DNA in renal transplant recipients within the typical clinical context of a developing country where virtually 100% of both receptors and donors are seropositive for this virus, we have undertaken HCMV DNA quantification using a simple, semi-quantitative, limiting dilution polymerase chain reaction (PCR). We evaluated this assay prospectively in 52 renal transplant patients from whom a total of 495 serial blood samples were collected. The samples scored HCMV positive by qualitative PCR had the levels of HCMV DNA determined by end-point dilution-PCR. All patients were HCMV DNA positive during the monitoring period and a diagnosis of symptomatic infection was made for 4 of 52 patients. In symptomatic patients the geometric mean of the highest level of HCMV DNAemia was 152,000 copies per 10(6) leukocytes, while for the asymptomatic group this value was 12,050. Symptomatic patients showed high, protracted HCMV DNA levels, whereas asymptomatic patients demonstrated intermittent low or moderate levels. Using a cut-off value of 100,000 copies per 10(6) leukocytes, the limiting dilution assay had sensitivity of 100%, specificity of 92%, a positive predictive value of 43% and a negative predictive value of 100% for HCMV disease. In this patient group, there was universal HCMV infection but relatively infrequent symptomatic HCMV disease. The two patient groups were readily distinguished by monitoring with the limiting dilution assay, an extremely simple technology immediately applicable in any clinical laboratory with PCR capability.


Assuntos
Infecções por Citomegalovirus/diagnóstico , Citomegalovirus/isolamento & purificação , DNA Viral/isolamento & purificação , Transplante de Rim , Leucócitos/virologia , Reação em Cadeia da Polimerase/métodos , Carga Viral , Anticorpos Antivirais/análise , Citomegalovirus/genética , Infecções por Citomegalovirus/sangue , Infecções por Citomegalovirus/virologia , DNA Viral/sangue , Humanos , Imunoglobulina G/análise , Imunoglobulina M/análise , Estudos Prospectivos
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