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1.
Dis Esophagus ; 29(8): 977-982, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26541352

RESUMO

We describe an adult cohort with eosinophilic esophagitis (EoE) and evidence of celiac disease (CD), propose a change in diagnostic practice to better characterize these conditions, and hypothesize new directions for research. Pediatric studies postulate association between gluten sensitivity and EoE. However, few publications describe the prevalence, detection, or therapeutic and pathophysiologic implications of such association in adults. Retrospective chart review was done on patients diagnosed with EoE from 2009 to 2010 at University of Utah Hospitals and Clinics. Data included sex, age, presentation, duodenal pathology, tissue transglutaminase immunoglobulin A antibody (TTG) positivity, human leukocyte antigen (HLA) type (when indicated), and gross and microscopic Esophagogastroduodenoscopy (EGD) findings. Duodenal biopsy, TTG results, and HLA type were correlated. Endoscopy was repeated after gluten-free diet. Forty-four of 75 patients were followed in EoE specialty clinic with duodenal biopsy and TTG testing per protocol. Six EoE patients had potential or probable CD. No sex or age differences were noted between those with findings of CD and EoE and those with EoE alone. Six patients with findings of CD and EoE followed gluten-free diet. Five underwent repeat endoscopy. Three had resolution of esophageal eosinophilia. Potential or probable CD was commonly found in adults with EoE. Diagnosis of CD may be challenging due to nonspecific symptoms and insufficient duodenal biopsy and serologic testing. Furthermore, gluten-free diet resolved EoE findings in some patients, suggesting possible shared pathophysiology in some cases of EoE and CD. TTG testing and adequate duodenal biopsy may further direct clinical care for EoE patients, and studies are needed to elucidate mechanisms linking EoE and CD.


Assuntos
Doença Celíaca/complicações , Esofagite Eosinofílica/complicações , Adulto , Estudos de Casos e Controles , Doença Celíaca/imunologia , Doença Celíaca/patologia , Estudos de Coortes , Duodeno/patologia , Endoscopia do Sistema Digestório , Esofagite Eosinofílica/patologia , Esofagite Eosinofílica/fisiopatologia , Feminino , Proteínas de Ligação ao GTP/imunologia , Humanos , Imunoglobulina A/imunologia , Imunoglobulina G/imunologia , Masculino , Pessoa de Meia-Idade , Proteína 2 Glutamina gama-Glutamiltransferase , Estudos Retrospectivos , Transglutaminases/imunologia
2.
Aliment Pharmacol Ther ; 41(12): 1288-95, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25898774

RESUMO

BACKGROUND: Acknowledging that eosinophilic esophagitis (EoE) is a disease with variable involvement throughout the oesophagus, studies have suggested a minimum of five biopsies to diagnose EoE. Although it is accepted that furrows and exudates appear to represent areas of inflammation, no research to date has looked specifically at EoE endoscopic findings to see if eosinophilic infiltrate correlates with specific endoscopic findings. AIM: To evaluate the distribution of eosinophils in EoE and determine whether endoscopic appearances predict the degree of eosinophilia at various locations of the oesophagus. METHODS: We performed a prospective cross sectional study of EoE (treated and untreated) patients to study the distribution of eosinophils according to endoscopic findings. The oesophagus of 10 EoE patients were biopsied up to 32 times in a circumferential manner. The mucosal changes were documented at the site of each biopsy. Histological determination of eosinophil counts and related histopathology of the oesophagus were then correlated with endoscopic findings. Similar biopsy assessments were made in treated (resolved) EoE patients (n = 6) to determine the permanence of specific endoscopic appearances. RESULTS: A total of 16 patients were biopsied (10 EoE, 6 treated EoE). A total of 432 biopsies were obtained in all with 294 biopsies from 10 EoE subjects. Eosinophil density was increased distally in the majority of EoE patients. Biopsies performed in areas of exudates and furrows demonstrated higher eosinophil counts. Lines and normal-appearing oesophagi in EoE subjects were not commonly associated with elevated eosinophil counts (>15 eos/HPF). Rings alone without associated furrows or plaques did not demonstrate elevated eosinophil counts and were seen in resolved EoE (Rx-EoE) as well as in active EoE patients. CONCLUSIONS: Eosinophilic esophagitis remains a variable disease with some patients manifesting extensive disease throughout the oesophagus. Characteristics of furrows and exudates found during endoscopy are associated with higher peak eosinophil counts, requiring fewer biopsies to make a diagnosis. Lines and otherwise normal appearances of the oesophagus suggest a milder mucosal eosinophilia, requiring substantial biopsies to adequately identify fields with diagnostic eosinophil counts.


Assuntos
Esofagite Eosinofílica/diagnóstico , Esofagite Eosinofílica/patologia , Adulto , Biópsia , Estudos Transversais , Diagnóstico Diferencial , Endoscopia , Eosinofilia/patologia , Eosinófilos/metabolismo , Feminino , Humanos , Inflamação/patologia , Contagem de Leucócitos , Masculino , Meridianos , Pessoa de Meia-Idade , Mucosa/patologia , Estudos Prospectivos
3.
J Natl Cancer Inst ; 93(11): 858-65, 2001 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-11390535

RESUMO

BACKGROUND: Colorectal cancer cells are shed into the stool, providing a potential means for the early detection of the disease using noninvasive approaches. Our goal was to develop reliable, specific molecular genetic tests for the detection of colorectal cancer in stool samples. METHODS: Stool DNA was isolated from paired stools and primary tumor samples from 51 colorectal cancer patients. Three genetic targets-TP53, BAT26, and K-RAS-were used to detect tumor-associated mutations in the stool prior to or without regard to the molecular analyses of the paired tumors. TP53 gene mutations were detected with a mismatch-ligation assay that detects nine common p53 gene mutations. Deletions within the BAT26 locus were detected by a modified solid-phase minisequencing method. Mutations in codons 12 and 13 of K-RAS were detected with a digital polymerase chain reaction-based method. RESULTS: TP53 gene mutations were detected in the tumor DNA of 30 patients, all of whom had the identical TP53 mutation in their stools. Tumors from three patients contained a noninherited deletion at the BAT26 locus, and the same alterations were identified in these patients' stool specimens. Nineteen of 50 tumors tested had a K-RAS mutation; identical mutations were detected in the paired stool DNA samples from eight patients. In no case was a mutation found in stool that was not also present in the primary tumor. Thus, the three genetic markers together detected 36 (71%) of 51 patients (95% confidence interval [CI] = 56% to 83%) with colorectal cancer and 36 (92%) of 39 patients (95% CI = 79% to 98%) whose tumors had an alteration. CONCLUSION: We were able to detect the majority of colorectal cancers by analyzing stool DNA for just three genetic markers. Additional work is needed to determine the specificity of these genetic tests for detecting colorectal neoplasia in asymptomatic patients and to more precisely estimate the prevalence of the mutations and sensitivity of the assay.


Assuntos
Neoplasias do Colo/diagnóstico , Neoplasias do Colo/genética , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/genética , DNA/genética , Fezes/química , Genes p53 , Genes ras , Mutação , Idoso , Neoplasias do Colo/patologia , Neoplasias Colorretais/patologia , DNA/isolamento & purificação , Marcadores Genéticos , Mutação em Linhagem Germinativa , Humanos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Reação em Cadeia da Polimerase/métodos , Reprodutibilidade dos Testes , Deleção de Sequência
4.
Gastroenterology ; 119(5): 1219-27, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11054379

RESUMO

BACKGROUND & AIMS: Assay of altered DNA exfoliated into stool represents an intriguing approach to screen for colorectal neoplasia, but multiple markers must be targeted because of genetic heterogeneity. We explored the feasibility of a stool assay panel of selected DNA alterations in discriminating subjects with colorectal neoplasia from those without. METHODS: Freezer-archived stools were analyzed in blinded fashion from 22 patients with colorectal cancer, 11 with adenomas > or =1 cm, and 28 with endoscopically normal colons. After isolation of human DNA from stool by sequence-specific hybrid capture, assay targets included point mutations at any of 15 sites on K-ras, p53, and APC genes; Bat-26, a microsatellite instability marker; and highly amplifiable DNA. RESULTS: Analyzable human DNA was recovered from all stools. Sensitivity was 91% (95% confidence interval, 71%-99%) for cancer and 82% (48%-98%) for adenomas > or =1 cm with a specificity of 93% (76%-99%). Excluding K-ras from the panel, sensitivities for cancer were unchanged but decreased slightly for adenomas to 73% (39%-94%), while specificity increased to 100% (88%-100%). CONCLUSIONS: Assay of altered DNA holds promise as a stool screening approach for colorectal neoplasia. Larger clinical investigations are indicated.


Assuntos
Adenocarcinoma/diagnóstico , Adenoma/diagnóstico , Neoplasias do Colo/diagnóstico , DNA de Neoplasias/análise , Fezes/química , Neoplasias Retais/diagnóstico , Adenocarcinoma/genética , Adenoma/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias do Colo/genética , DNA/análise , DNA/química , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Neoplasias Retais/genética , Valores de Referência , Sensibilidade e Especificidade , Método Simples-Cego
5.
Gynecol Oncol ; 78(2): 152-7, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10926795

RESUMO

OBJECTIVES: Development of genetic heterogeneity is one mechanism whereby tumors may acquire increasing aggressiveness during neoplastic progression. In this study we relate development of intratumoral genetic heterogeneity to invasion and metastatic spread of sporadic endometrioid (type I) endometrial adenocarcinomas. METHODS: Microsatellite unstable adenocarcinomas underwent detailed microsatellite allelotype mapping with reconstruction of neoplastic lineages using maximum parsimony analysis. RESULTS: Within individual patients, tumor allelotypes sometimes varied between regions of histologically identical tumor, indicating that genotypic variation may reflect differences inapparent by histology. Comparison of noninvasive (surface/luminal) with invasive (myometrial invasion or metastasis) carcinoma showed highly related genotypes in 3/8 cases in which the invasive component can be recognized as evolved from the superficial tumor lineage by progressive clonal selection. In 3/8 cases superficial and invasive genotypes independently evolved different sets of altered microsatellites, indicating either divergence at an early stage in tumor evolution or independent selection events. A total of 2/8 cases had random patterns of marker distribution between sampled areas that were not informative in delineating systematic relationships between surface and invasive tumor. CONCLUSIONS: We conclude from these results that endometrial tumor progression may occur through physical extension of existing clones or through creation of new subclones with altered growth properties. The latter occurs in about half of cases, where myometrial invasion may select for particular clones that are poorly represented on the luminal surface.


Assuntos
Carcinoma Endometrioide/genética , Carcinoma Endometrioide/patologia , Neoplasias do Endométrio/genética , Neoplasias do Endométrio/patologia , Heterogeneidade Genética , Alelos , DNA de Neoplasias/análise , DNA de Neoplasias/genética , Progressão da Doença , Feminino , Genótipo , Humanos , Repetições de Microssatélites/genética , Invasividade Neoplásica , Filogenia
6.
Am J Clin Pathol ; 113(4): 576-82, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10787358

RESUMO

Microsatellite instability is a frequent (13%-24%) finding in sporadic endometrial adenocarcinoma and its precursor lesions, but most studies are limited to patients who already have malignant or premalignant endometrial disease. We performed retrospective testing for microsatellite instability in women in whom cancers showing microsatellite instability developed later and prospective testing in randomly selected normal and anovular endometrial biopsy specimens. Microsatellite instability in cancer-bearing biopsy specimens accurately reflected that seen in matched malignant tissues obtained at hysterectomy. In 1 patient, microsatellite instability developed in a scanty sample of fragmented endometrial tissues 7 years before the onset of endometrial cancer. Prospective testing for microsatellite instability in the endometria of women unselected for subsequent appearance of endometrial cancer showed a very low rate of microsatellite instability. Only 1 endometrial specimen showing microsatellite instability was found among 75 anovulatory endometrial specimens, and none were found in 377 normal endometrial specimens and 46 polyps examined. Microsatellite instability may precede the onset of histologically diagnosed carcinoma but is rare in randomly sampled histologically normal endometrial tissues.


Assuntos
Carcinoma Endometrioide/genética , Neoplasias do Endométrio/genética , Endométrio/patologia , Repetições de Microssatélites/genética , Lesões Pré-Cancerosas/genética , Carcinoma Endometrioide/patologia , Carcinoma Endometrioide/cirurgia , Curetagem , Primers do DNA/química , DNA de Neoplasias/análise , Neoplasias do Endométrio/patologia , Neoplasias do Endométrio/cirurgia , Endométrio/efeitos dos fármacos , Estrogênios/efeitos adversos , Feminino , Humanos , Histerectomia , Reação em Cadeia da Polimerase , Lesões Pré-Cancerosas/patologia , Estudos Prospectivos , Estudos Retrospectivos , Sensibilidade e Especificidade
7.
Am J Pathol ; 152(5): 1313-8, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9588899

RESUMO

The pathogenesis of carcinoma of the vulva is diverse and includes both human papilloma virus (HPV)-positive and HPV-negative pathways. The objective of this study was to correlate the morphology with patterns of loss of heterozygosity (LOH) within four vulvar carcinomas and in adjacent vulvar epithelia. Tumors were categorized as HPV positive or negative by polymerase chain reaction (PCR) analysis. Forty-one different sites of normal squamous mucosa, hyperplasia, vulvar intraepithelial neoplasia (VIN), and carcinoma were microdissected in duplicate, and each extracted DNA was analyzed in duplicate for LOH at 10 chromosomal loci by PCR and polyacrylamide gel electrophoresis. Patterns of LOH were compared within different sites of tumors and between the tumor and the noninvasive epithelia. Of three tumors with multiple invasive foci analyzed, divergent patterns of LOH were identified in two, correlating in one with differences in tumor grade. In one HPV-16-positive case, multiple sites of VIN displayed heterogeneity for LOH consistent with divergent clonal or subclonal populations, some of which were not shared by the tumor. In one HPV-negative case, LOH was found in foci of hyperplasia and differentiated VIN (atypical hyperplasia), the latter sharing LOH with the invasive carcinoma at some but not all chromosomal loci. This study suggests that a genetic relationship exists between VIN and carcinoma, irrespective of HPV involvement. It also suggests that in HPV-negative tumors, allelic loss may predate the onset of invasive carcinoma and, in some cases, cellular atypia (VIN). However, the divergent patterns of LOH observed imply that many genetic alterations in the adjacent vulvar epithelium are not directly related to the invasive carcinoma.


Assuntos
Carcinoma in Situ/patologia , Carcinoma de Células Escamosas/patologia , Perda de Heterozigosidade , Vulva/patologia , Neoplasias Vulvares/patologia , Carcinoma in Situ/genética , Carcinoma in Situ/virologia , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/virologia , DNA de Neoplasias/genética , DNA Viral , Epitélio/patologia , Epitélio/virologia , Feminino , Humanos , Hiperplasia , Mucosa/patologia , Mucosa/virologia , Papillomaviridae/genética , Papillomaviridae/isolamento & purificação , Polyomaviridae , Estudos Retrospectivos , Infecções Tumorais por Vírus/complicações , Infecções Tumorais por Vírus/patologia , Vulva/virologia , Neoplasias Vulvares/genética , Neoplasias Vulvares/virologia
9.
Am J Pathol ; 150(1): 315-22, 1997 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9006346

RESUMO

Squamous neoplasms of the female genital tract, including vulvar intraepithelial neoplasia, presumably are derived from a single cell. This study addressed this hypothesis and determined the clonal status of other squamous epithelial alterations associated with vulvar carcinoma, including hyperplasia and lichen sclerosis. X chromosome inactivation patterns of 22 epithelial lesions and matched normal epithelium were determined using a polymerase chain reaction (PCR)-based assay targeting the X-linked human androgen receptor gene (HUMARA). Clonality was inferred by comparing matched lesional and control tissues as follows: 1) monoclonal, if intensity of either PCR product was skewed relative to normal reference epithelium (control), 2) polyclonal, if both lesional and control were unskewed, and 3) unknown, if both lesion and control tissues were skewed toward the same allele. Two cases were excluded because of noninformative homozygous HUMARA alleles. Of 8 vulvar intraepithelial neoplasias analyzed, 7 were scored monoclonal and 1 polyclonal. Of 12 hyperplasias, 6 were monoclonal, including one with lichen sclerosis, 2 were polyclonal, and in 4, the clonal status could not be determined. The PCR-based clonal assay supports a monoclonal derivation for vulvar intraepithelial neoplasia and, in some cases, vulvar hyperplasia, and lichen sclerosis. The finding of monoclonal hyperplasia and lichen sclerosis suggests that clonal expansion may evolve before the development of morphological atypia in these epithelia.


Assuntos
Carcinoma in Situ/genética , Carcinoma in Situ/patologia , Vulva/patologia , Neoplasias Vulvares/genética , Neoplasias Vulvares/patologia , Células Clonais/patologia , Feminino , Humanos , Hiperplasia , Invasividade Neoplásica , Reação em Cadeia da Polimerase , Cromossomo X/patologia
10.
Pediatr Pathol Lab Med ; 16(6): 865-75, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-9025885

RESUMO

Congenital masses of the sacrococcygeal region commonly contain multiple tissues and have variously been subclassified as neoplasms or congenital hamartomas based on clinicopathological and embryological observations. We have used a polymerase chain reaction-based assay for nonrandom X chromosome inactivation to infer the clonality of three cogenital sacrococcygeal tumors previously diagnosed as teratomas. One solid immature teratoma was monoclonal, and a predominantly cystic histologically mature mass was polyclonal. A third immature teratoma was noninformative because of baseline asymmetry of polyclonal tissue X inactivation. We confirm that immature teratomas at this site appear to be monoclonal neoplasms and suggest that at least some histologically mature "teratomas" are more appropriately classified as hamartomas.


Assuntos
Clonagem Molecular/métodos , Neoplasias Retroperitoneais/congênito , Neoplasias Retroperitoneais/patologia , Região Sacrococcígea/patologia , Neoplasias de Tecidos Moles/congênito , Neoplasias de Tecidos Moles/patologia , Teratoma/congênito , Teratoma/patologia , Feminino , Humanos , Recém-Nascido , Reação em Cadeia da Polimerase , Receptores Androgênicos/análise , Neoplasias Retroperitoneais/genética , Estudos Retrospectivos , Neoplasias de Tecidos Moles/genética , Teratoma/genética
11.
Cancer Res ; 56(19): 4483-6, 1996 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-8813144

RESUMO

Progressive microsatellite changes in replication error positive (RER+) endometrium were used to reconstruct evolutionary stages of nonfamilial adenocarcinoma. RER+ putative endometrial precancers (atypical endometrial hyperplasias) progress to RER+ carcinomas, which retain some of the altered microsatellites acquired in earlier precursor stages. The RER+ phenotype may provide a specific marker for early-stage endometrial neoplasms that cannot be resolved by routine histopathology and may be a useful tool to stratify stages in the evolution of RER+ tumors.


Assuntos
Adenocarcinoma/genética , Alelos , DNA de Neoplasias/genética , Neoplasias do Endométrio/genética , Repetições de Microssatélites , Lesões Pré-Cancerosas/genética , Doenças Uterinas/genética , Adenocarcinoma/patologia , Idoso , Idoso de 80 Anos ou mais , Linhagem da Célula , DNA/genética , Neoplasias do Endométrio/patologia , Endométrio/química , Endométrio/patologia , Feminino , Humanos , Hiperplasia , Pessoa de Meia-Idade , Lesões Pré-Cancerosas/patologia , Doenças Uterinas/patologia
12.
Cancer Res ; 56(8): 1917-21, 1996 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-8620514

RESUMO

We have tested the hypothesis that endometrial precancers persist in uteri of patients with endometrial carcinoma and are monoclonal. Twenty-two hysterectomies with both well-differentiated endometrial adenocarcinoma and adjacent (normal or abnormal) noncancerous endometrium underwent successful clonal analysis using a PCR assay for nonrandom X chromosome inactivation. Monoclonal lesions included endometrial carcinoma, endometrial polyps, and atypical endometrial hyperplasias, whereas normal and anovulatory endometrium were polyclonal. Comparison of the specific X chromosome copy preferentially inactivated by the matched monoclonal cancers and associated monoclonal lesions allowed us to exclude polyps, but not endometrial hyperplasias, as potential precancers. The repetitive genetic marker (HUMARA) for X inactivation was altered in some cancers, permitting identification of microsatellite instability (RER+). Two patients with RER+ cancers also had adjacent RER+ hyperplasias. The seven monoclonal and two RER+ hyperplasias had focal or diffuse cytological atypia, a feature previously associated with risk for endometrial cancer. We conclude that: (a) putative endometrial precancers and cancers share a monoclonal growth pattern; (b) cancers with microsatellite instability may acquire this feature as precancers; and (c) monoclonal endometrial precancers have the morphology of hyperplasias, which vary in the extent of cytological atypia and degree of architectural complexity.


Assuntos
Adenocarcinoma/patologia , DNA de Neoplasias/genética , DNA Satélite/genética , Neoplasias do Endométrio/patologia , Lesões Pré-Cancerosas/patologia , Doenças Uterinas/patologia , Neoplasias Uterinas/patologia , Útero/patologia , Cromossomo X , Adenocarcinoma/genética , Adenocarcinoma/cirurgia , DNA de Neoplasias/análise , DNA Satélite/análise , Neoplasias do Endométrio/genética , Neoplasias do Endométrio/cirurgia , Endométrio/patologia , Feminino , Humanos , Hiperplasia , Histerectomia , Repetições de Microssatélites/genética , Reação em Cadeia da Polimerase , Lesões Pré-Cancerosas/genética , Neoplasias Uterinas/genética
13.
Cancer Res ; 55(21): 5080-4, 1995 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-7585555

RESUMO

Monoclonal proliferative lesions may be identified by X chromosome inactivation skewing relative to normal polyclonal tissues. We have quantitatively analyzed X-inactivation patterns throughout polyclonal uterine tissues to develop interpretive criteria for recognition of monoclonal neoplasms. Six fresh tissue samples (two samples each of cervix, endometrium, and myometrium) were collected from hysterectomy specimens, and the percentage of androgen receptor (HUMARA) marker allele present on inactive X chromosomes was calculated from a PCR assay. Exact balancing yields 50% of the marker on the inactive X, whereas complete skewing shows either 0 or 100%. X inactivation was similar throughout the tissues of each uterus but was significantly different among the 11 women studied. Comparison of differences in X inactivation between pairs of polyclonal tissue samples within each uterus (Xi spread) permitted delineation of cumulative experimental and biological variation of this parameter. Polyclonal-polyclonal Xi spread averaged 10.7 and was independent of the tissue type, sampling site, or the individual studied. Severe baseline skewing of reference polyclonal tissues or contamination of monoclonal tissue by polyclonal cells may reduce the polyclonal-monoclonal Xi spread. The extent of X-inactivation skewing necessary to infer a monoclonal process should exceed the 20 or 27 point spread seen, respectively, between 85 and 95% of polyclonal samples.


Assuntos
Mecanismo Genético de Compensação de Dose , Neoplasias do Endométrio/genética , Lesões Pré-Cancerosas/genética , Útero/ultraestrutura , Sequência de Bases , Colo do Útero/citologia , Colo do Útero/fisiologia , Colo do Útero/ultraestrutura , Endométrio/citologia , Endométrio/fisiologia , Endométrio/ultraestrutura , Feminino , Homozigoto , Humanos , Individualidade , Dados de Sequência Molecular , Miométrio/citologia , Miométrio/fisiologia , Miométrio/ultraestrutura , Reação em Cadeia da Polimerase , Receptores Androgênicos/genética , Células-Tronco/citologia , Células-Tronco/ultraestrutura , Útero/citologia , Útero/fisiologia
14.
Nucleic Acids Res ; 23(8): 1411-8, 1995 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-7753634

RESUMO

Trinucleotide CAG repeats in the X-linked human androgen receptor gene (HUMARA) have proved a useful means of determining X chromosome haplotypes, and when combined with methylation analysis of nearby cytosine residues permits identification of non-random X inactivation in tumors of women. Co-amplification of two alleles in a heterozygote generates PCR products which differ in the number of CAG units, and thus their melting and secondary structure characteristics. We have shown that under optimal conditions amplification efficiency of two HUMARA alleles is near-equivalent, generating PCR products in a ratio proportional to that of the genomic template. In contrast, reduction of template quantity, damage of template by ultraviolet irradiation or addition of monovalent salts (sodium chloride, sodium acetate or ammonium acetate) produces highly variable imbalances of allelic PCR products, with a strong tendency to preferentially amplify lower molecular weight alleles. Variability and biasing was diminished by substitution of 7-deaza-2'-dGTP for dGTP during amplification, an intervention which reduces stability of intramolecular and intermolecular GC base pairing. We conclude that DNA which is scanty, damaged or salt contaminated may display amplification bias of GC-rich PCR targets, potentially confounding accurate interpretation or reproducibility of assays which require co-amplification of alleles.


Assuntos
Alelos , Reação em Cadeia da Polimerase/métodos , Receptores Androgênicos/genética , Sequências Repetitivas de Ácido Nucleico/genética , Composição de Bases , Sequência de Bases , DNA/genética , DNA/efeitos da radiação , Nucleotídeos de Desoxiguanina/metabolismo , Feminino , Marcadores Genéticos , Humanos , Masculino , Dados de Sequência Molecular , Conformação de Ácido Nucleico , Desnaturação de Ácido Nucleico , Espermatozoides , Raios Ultravioleta , Útero
15.
Lasers Surg Med ; 11(4): 385-7, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1895869

RESUMO

Bowen's disease (intraepithelial squamous cell carcinoma) may occasionally occur in anal canal or perianal region. Surgical excision in this area may result in significant complications and a recurrence rate of 9-19%. A case of successful treatment of anal and perianal Bowen's disease using argon laser therapy is presented. No acute or chronic complications resulted from laser therapy. Twenty-eight months after the initial diagnosis the patient is disease free. Laser therapy also provides the potential for repeated treatment of recurrent lesions without significant patient discomfort or inconvenience. Argon laser therapy should be considered as a therapeutic option in the treatment of Bowen's disease.


Assuntos
Neoplasias do Ânus/cirurgia , Doença de Bowen/cirurgia , Fotocoagulação , Neoplasias Primárias Múltiplas/cirurgia , Neoplasias Retais/cirurgia , Neoplasias Cutâneas/cirurgia , Argônio , Humanos , Lasers , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia
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