ISSN:1052-9551    

出版商:OVID    

年代:1995

数据来源: OVID

ISSN:1052-9551    

出版商:OVID    

年代:1995

数据来源: OVID

摘要:

In nasal biopsies from 17 adult patients with seasonal allergic rhinitis and from 10 healthy controls, cytokines were analyzed by reverse-transcriptase polymerase chain reaction (RT-PCR). The time-course study during winter included repeated local allergen provocation with subsequent nasal biopsies as well as biopsies taken during pollen season. The RT-PCR for CD44 yielded positive bands in 65 of 71 cases, in which cases mRNA for interleukins 2, 4, and 5 (IL-2, IL-4, and IL-5) were thus investigated by means of seminested PCR. IL-4 mRNA was found almost exclusively in the allergic patients. During provocation a significant increase in IL-4 was noticed compared with controls (p = 0.043). Equally, during the natural pollen season, IL-4 mRNA expression was significantly higher in patientsnotusing nasal corticosteroids compared with those who did (p = 0.011). No differences in IL-2 or IL-5 were observed between the groups. These findings also indicate, together with earlier observations of T-cell activation, a phenotype switch toward T-helper 2 (Th2) cells, and the accumulation (homing) of these T cells in the nasal mucosa, that T cells constitute the main source for IL-4 in the nasal mucosa. Therefore, allergic patients have an increased synthesis of IL-4 when provoked with the allergen, and during natural pollen season this synthesis can be downregulated by corticosteroids. Furthermore, this study exemplifies the versatility of molecular biology in surgical pathology and that even low-copy-number cytokine mRNA can be examined in routinely snap-frozen surgical specimens.

ISSN:1052-9551    

出版商:OVID    

年代:1995

数据来源: OVID

摘要:

Fifty-three non-small cell lung carcinomas (NSCLC), previously investigated forp53abnormalities, were studied to evaluate the status of themdm2gene by Southern and Northern blot analysis and expression of the mdm2 protein by immunohistochemistry with specific monoclonal antibodies. Amplification and overexpression of themdm2gene and nuclear accumulation of its protein product were observed in three (6%) of the NSCLC examined. All of the tumors havingmdm2abnormalities belonged to a subset of NSCLC characterized by a strong accumulation of the p53 protein in the absence ofp53gene mutations. Since mdm2 is capable of forming tight complexes with p53, possibly stabilizing it, our results suggest that this event may take place in a low percentage of NSCLC. Moreover, all of themdm2-positive tumors were histologically classified as lung adenocarcinomas. This may indicate that the mdm2 gene is preferentially altered in this particular subtype of lung tumors.

ISSN:1052-9551    

出版商:OVID    

年代:1995

数据来源: OVID

摘要:

The purpose of this study was to compare the serological analysis for hepatitis C infection using the recombinant immunoblot assay (RIBA) to the direct in situ localization of the hepatitis C viral genome using the reverse transcriptase (RT) in situ PCR technique. Concurrent sera and liver biopsies from 42 patients with clinical and histologic evidence of chronic liver disease were studied. Antibodies against hepatitis C specific antigens were demonstrated by RIBA in the sera of 39/42 (92%), and PCR amplified viral cDNA was detected in the biopsies of 21 (54%) of the 39 seropositive patients. The detection rate using standard in situ hybridization for the tissues known to be viral positive with RT in situ PCR was 9/21 (42%). It is concluded that approximately one-half of patients with chronic hepatitis and serologic evidence of hepatitis C infection will not have virus detectable in their liver biopsy even with a highly sensitive PCR-based technique.

ISSN:1052-9551    

出版商:OVID    

年代:1995

数据来源: OVID

摘要:

We have developed and tested a rapid and sensitive method of detecting expansion of T-cell clones using the polymerase chain reaction (PCR) and a single set of consensus primers for the V and J regions to amplify rearranged T-cell receptor-γ (TCR-γ) genes. Monoclonality was continued in all of the 18 cases of T-cell neoplasms tested, but not in reactive lymphadenopathy, non-Hodgkin's B lymphomas, and Hodgkin s disease. PCR analysis, using the primer sequence outlined in this study, had an overall specificity of 100% when compared with Southern blot analysis. No false-negative results were observed, certainly owing to the choice of consensus primers and to the control of PCR reactions on agarose gels before testing for clonality by separation of PCR products on polyacrylamide gels. This method for the detection of T-cell monoclonality can be especially useful in cases that are diagnostically problematic with standard histological and immunological analysis and in cases where the material available is limited.

ISSN:1052-9551    

出版商:OVID    

年代:1995

数据来源: OVID

摘要:

Clonality studies have suggested that neoplasms are monoclonal and hyperplasias are polyclonal. To investigate this question in thyroid, we analyzed the clonality of 26 morphologically characterized hyperplastic nodules from 19 patients with sporadic goiters. For comparison we studied six thyroid carcinomas. We used the highly informative M27β probe that maps to the X-chromosome DXS255 locus (X cen-p 11.22). Material was obtained from 52 nodules; tissue from nine nodules was rejected because of contamination with normal elements, five patients (eight nodules) were homozygous atPstI sites in nonnodular thyroid tissue, and three nodules were excluded for technical reasons. Methylation patterns afterHpaII digestion confirmed polyclonality in all nontumorous thyroids of informative patients. Seven hyperplastic nodules were polyclonal, and 18 were monoclonal; one showed loss of heterozygosity. One nodule exhibited aberrant methylation. Multiple nodules were obtained from four patients; in three, all were monoclonal with activation of the same allele. Three papillary carcinomas were monoclonal; two exhibited aberrant methylation. One follicular carcinoma showed loss of heterozygosity. Our data indicate that morphologically indistinguishable hyperplastic thyroid nodules may be monoclonal or polyclonal. These findings suggest that variable molecular mechanisms are involved in the pathogenesis of nodules in sporadic goiter. Future studies will need to explore the biological significance of nodules of variable clonal origin.

ISSN:1052-9551    

出版商:OVID    

年代:1995

数据来源: OVID

摘要:

A prospective study was undertaken to determine the prevalence and histological correlates of human papillomavirus infection in the head and neck epithelium. Oral, pharyngeal, and laryngeal paraffin-embedded samples were analyzed by polymerase chain reaction with use of human papillomavirus E6 consensus sequence primers. Human papillomavirus infection was detected in 20 of 126 (15.9%) patients. Twenty-five of 230 (10.9%) samples contained human papillomavirus DNA. Papillomaviruses were detected in 15 of 131 (11.4%) head and neck squamous cell carcinomas, in 3 of 32 (9.4%) dysplasias, and 2 of 19 (10.5%) keratoses. The most commonly identified human papillomavirus in cancerous, precancerous, and keratotic lesions was type 16 (80.0% of the isolates). Five papillomas were shown to contain human papillomavirus type 6. No other lesion in 42 samples contained human papillomavirus. Our data are consistent with the hypothesis that infection with certain types of human papillomavirus contributes to head and neck cancer although this may be so only in a minority of cases. Human papillomavirus infection may play a role in the earliest stages of tumorigenesis, since papillomaviruses can be found in laryngeal premalignant and keratotic lesions, which are closely linked to tobacco use.

ISSN:1052-9551    

出版商:OVID    

年代:1995

数据来源: OVID

摘要:

The expression and degree of amplification of the MYCN oncogene in neuroblastoma provide an important indicator of disease prognosis. Detection of MYCN amplification has been described using Southern blotting or polymerase chain reaction (PCR) on DNA from fresh or frozen tissue samples, and using in situ hybridization mainly on metaphase spreads or smears of cultured neuroblastoma cells. In this article, we describe fluorescence in situ hybridization (FISH) results on detection of MYCN amplification in formalin-fixed, paraffin-embedded samples of 25 neuroblastoma and 20 nonneuroblastoma pediatric tumors. MYCN amplification was readily detectable by FISH in eight of the neuroblastomas; correlation with results obtained by Southern analysis was perfect. Of the nonneuroblastoma tumors, only one of three retinoblastoma cases showed MYCN amplification. In contrast to the Southern blot technique, FISH demonstrated the state of amplification heterogeneity of the tumor cells as well as the nature of the amplification units: double-minute chromosomes (DMs) or homogeneously staining regions (HSRs). The results indicate that FISH is a rapid and reliable method for detection of MYCN oncogene amplification in routinely processed samples and may be used to supplant the Southern blot technique.

ISSN:1052-9551    

出版商:OVID    

年代:1995

数据来源: OVID

摘要:

Twenty-four normal or benign breast tissues were examined for the expression of transforming growth factor-α (TGFα), epidermal growth factor receptor (EGFR), and P-glycoprotein, the product of themdr-1 gene. Specific staining for all three proteins was observed in the majority of the samples. P-glycoprotein staining was present in most (88%), and confined to the lumenal surface of the ductal epithelium. Membranous EGFR expression was observed in epithelial cells in 92% of the specimens and 42% displayed both myoepithelial and epithelial cell staining. TGFα staining was intense and uniformly distributed through the cytoplasm (96%). Coexpression of EGFR, TGFα, and P-glycoprotein in normal human breast tissues suggests a role for each of those proteins in normal breast physiology. An interaction may be present in normal breast tissue between the EGF receptor pathway and P-glycoprotein.

ISSN:1052-9551    

出版商:OVID    

年代:1995

数据来源: OVID