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1.
We hypothesized that in patients with chronic heart failure mesenteric venous congestion leads to increased bowel permeability, bacterial translocation, and thereby endotoxin release; the increased endotoxin challenge then causes immune activation with increased soluble CD14 levels and tumor necrosis factor (TNF)-alpha production. Patients with high soluble CD14 levels (indicative of endotoxin-cell interaction) have markedly increased plasma levels of TNF-alpha, soluble TNF receptors 1 and 2, and intracellular adhesion molecule-1, supporting this hypothesis.  相似文献   

2.
Characteristic chromosome aberrations have been identified in various tumors. Fluorescence in situ hybridization (FISH) using specific probes that are generated by vector cloning or in vitro amplification and labeled with fluorescent dyes allow for the detection of these genetic changes in interphase cells. This technique, that is also referred to as "interphase cytogenetics", can be performed in cytological preparations as well as in sections of routinely formaldehyde-fixed and paraffin-embedded tissue. In cancer research and diagnostics, interphase cytogenetics by FISH is used to detect numerical chromosome changes and structural aberrations, e.g., translocations, deletions, or amplifications. In this technical overview, we explain the principles of the FISH method and provide protocols for FISH in cytological preparations and paraffin sections. Moreover, possible applications of FISH are discussed.  相似文献   

3.
Although several factors affecting the sensitivity of polymerase chain reaction (PCR) amplification from formalin-fixed tissues have been investigated mostly by experiments, the feasibility of archival formalin-fixed, paraffin-embedded tissue samples stored in pathology departments for PCR amplification has rarely been examined directly. Thus, the feasibility of 74 archival unbuffered 10% formalin-fixed, paraffin-embedded tissues for PCR amplification with primers producing a 190 b.p. DNA segment of p53 exon 5 was investigated. Fixation time was the critical factor influencing the sensitivity of PCR amplification. All (6/6) of the samples fixed for only 1 day, 44% (7/16) of the samples fixed for 2-3 days and 14% (4/28) of the samples fixed for 4-6 days showed successful amplification, while no amplification was obtained for the samples fixed for 7 days or more. The peak size of DNA extracted from the archival tissues decreased as the fixation time became longer. Experiments using xenografted tumor tissues fixed for various times showed longer permissible fixation time; up to 9 days of fixation, decreasing amounts of PCR products were obtained while no amplification was obtained for the samples fixed for 12 days or more. The time in paraffin seemed to be a minor factor for PCR amplification since all of the 1 day fixation samples, including those that had been embedded for up to 5 years, resulted in efficient amplification. The size of the amplified DNA segments, however, could be another factor influencing the sensitivity of amplification because even the 1 day fixation samples showed less amplification of 345 b.p. DNA compared with those of 167 and 262 b.p. DNA. Additionally, a point mutation was detected in the amplified p53 products from archival tissues using a non-isotopic method, temperature gradient gel electrophoresis. In conclusion, archival tissue samples that had been fixed immediately for only up to 1 day were constantly available for PCR amplification of approximately 200 b.p. DNA segments, suggesting that surgical specimens should be subjected to cutting and paraffin embedding just after 1 day or less fixation for subsequent use in PCR amplification.  相似文献   

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BACKGROUND: Trichosporon beigelii, causal agent of white piedra can cause disseminated infection in immunodepressed subjects. Systemic infections due to this pathogen have been reported mainly in neutropenic patients and rarely in AIDS patients. CASE REPORT: A 36-year-old HIV+ man from Senegal was hospitalized for fever and meningoencephalitis associated with skin lesions. T. beigelii was isolated from skin biopsies and cerebrospinal fluid cultures. The patients was treated with amphotericin B with regression of the skin lesions. The diagnosis of disseminated T. beigelii infection was retained. DISCUSSION: Disseminated T. beigelii infections are known to occur in immunodepressed subjects, especially in case of neutropenia. In our patient, the presence of two proven localizations (meninges and skin) and the favorable outcome with amphotericin B favored disseminated infection. The good response to treatment can probably be explained by the absence of neutropenia. Skin lesions are frequent, usually occurring as disseminated papulae or purpural nodules. Pathology examination and skin biopsy culture can provide rapid diagnosis allowing appropriate treatment.  相似文献   

7.
Nuclear DNA ploidy has been shown to have an important prognostic association for patients with adenocarcinoma of the prostate. Flow cytometry and static image analysis are ploidy methods that have been used in prostate carcinoma. Fluorescence in situ hybridization (FISH) using chromosome-specific probes can be used to evaluate the ploidy of interphase nuclei. In this study FISH was compared with flow cytometry and static image analysis in determining ploidy in paraffin-embedded tissue from 34 prostatic adenocarcinomas. Ploidy status using FISH was determined by enumerating centromeres of two chromosomes (8 and 12) by use of directly-labeled alpha-satellite DNA probes in isolated whole nuclei obtained by the Hedley technique. All three methods identified 11 of 34 cases as diploid and 17 of 34 cases as nondiploid (82% concordance). Six cases were discordant; two cases had discrepant results by each method. Ploidy classification as determined by FISH had an 88% concordance with ploidy classification by either flow cytometry or static image analysis. In conclusion, FISH was found to be a sensitive method of ploidy analysis in isolated paraffin-embedded nuclei from prostate adenocarcinomas. When the chromosomes commonly involved in aneuploidy have been identified in prostate adenocarcinoma, FISH has the potential to provide greater sensitivity for aneuploidy detection compared with currently available methods.  相似文献   

8.
BACKGROUND: Histologic distinction of dermatofibrosarcoma protuberans (DFSP) from fibrous histiocytoma (FH) may be difficult. In addition, differential diagnosis is hampered by the lack of appropriate immunohistochemical markers that reliably distinguish between these two entities. OBJECTIVE: This study is aimed at the introduction of a monoclonal antibody (anti-human progenitor cell antigen-1; anti-CD34) that distinguishes between DFSP and FH in formalin-fixed, paraffin-embedded tissue. METHODS: Paraffin-embedded specimens of DFSP, FH, and other soft-tissue tumors were investigated for CD34 expression by anti-human progenitor cell antigen-1/alkaline phosphatase-antialkaline phosphatase immunostaining. RESULTS: Strong CD34 reactivity was present in each DFSP (n = 19) but was consistently absent from FH (n = 45) and other soft-tissue tumors (n = 47). CONCLUSION: CD34 immunostaining of paraffin-embedded specimens may be useful in differentiating between DFSP and FH.  相似文献   

9.
A novel assay based on a nested PCR and restriction enzyme analysis of the PCR products was developed for the rapid detection and identification of Mycobacterium bovis and M. avium-M. intracellulare species in formalin-fixed, paraffin-embedded tissue (PET) specimens. On the basis of the nucleotide sequence data obtained in the present study, general nested primers were constructed to amplify a 424-bp segment of the gene encoding the 65-kDa surface antigen of mycobacteria. The nested PCR assay proved to be highly sensitive, since as little as 5 to 10 fg of extracted mycobacterial DNA was detected. The safety of the assay as a routine method for the diagnosis of M. bovis and M. avium-M. intracellulare in PET specimens was provided by taking various precautions. In order to prevent false positivity, specific tools and procedures were applied. To detect false-negative results and assess the efficiency of the PCR, an internal standard molecule of amplification was constructed. The digestion of the amplicons with the restriction endonuclease Sau96-I allowed the identification of M. bovis and M. avium-M. intracellulare in a large number of clinical specimens. The present results indicate that PCR combined with an internal control of amplification and restriction enzyme analysis of the amplicons provides a rapid, sensitive, and reliable method for routine diagnostic laboratories to detect and identify M. bovis and M. avium-M. intracellulare in PET specimens.  相似文献   

10.
Immunoperoxidase and immunofluorescence techniques detected and localized infectious bursal disease virus (IBDV) in formalin-fixed paraffin-embedded sections of the bursa of Fabricius of experimentally and naturally infected chickens. The primary antibody was a monoclonal antibody that bound all IBDV serologic subtypes, including the GLS isolate. Both techniques were valuable in detecting IBDV. The presence and severity of microscopic lesions in the bursa correlated with the location and number of positive IBDV-infected cells as measured by either test. Mild vaccine strains induced minimal microscopic lesions and resulted in a few cells positive by either test. In contrast, virulent IBDV produced widespread lymphoid necrosis and numerous cells positive by both assays. The immunoperoxidase test was more useful than the immunofluorescence test, since the same section could be stained and examined by immunoperoxidase and then restained and examined for microscopic pathology. The presence of immunoperoxidase-positive stained cells associated with areas of microscopic pathology suggested that microscopic lesions were induced by IBDV.  相似文献   

11.
Four monoclonal antibodies (MAbs) with specificities for epitopes on human respiratory syncytial virus (RSV) proteins preserved after formalin fixation and paraffin embedding were identified in fixed and embedded virus-infected HEp-2 cell pellets. The MAbs bound epitopes on the fusion protein, the nucleoprotein, the phosphoprotein, and the M2 protein of the virus. Following high-temperature antigen unmasking, immunohistochemical staining revealed RSV antigens in the lungs of five of seven children who died with confirmed RSV infection and in none of nine children who died for other reasons, with no evidence of RSV infection. Staining was cytoplasmic, granular, and confined to epithelial cells. Intense staining was seen at the apex of ciliated bronchial and bronchiolar epithelial cells in all five positive cases. In one case, of pneumonitis, infected pneumocytes were present in the alveoli and in several cases, CD68-positive, cytokeratin-negative alveolar macrophages stained for viral antigens. These antibodies may prove useful in studies of the pathogenesis of RSV infection.  相似文献   

12.
Genomic in situ hybridization (GISH) using genomic DNA probes from Thinopyrum elongatum (Host) D.R. Dewey (genome E, 2n = 14), Thinopyrum bessarabicum (Savul. & Rayss) A. L?ve (genome J, 2n = 14), and Pseudoroegneria strigosa (M. Bieb.) A. L?ve (genome S, 2n = 14), was used to examine the genomic constitution of Thinopyrum intermedium (Host) Barkworth & D.R. Dewey (2n = 6x = 42) and Thinopyrum ponticum (Podp.) Barkworth & D.R. Dewey (2n = 10x = 70). Evidence from GISH indicated that hexaploid Th, intermedium contained the J, Js, and S genomes, in which the J genome was related to the E genome of Th. elongatum and the J genome of Th. bessarabicum. The S genome was homologous to the S genome of Ps. strigosa, while the Js genome referred to modified J- or E-type chromosomes distinguished by the presence of S genome specific sequences close to the centromere. Decaploid Th. ponticum had only the two basic genomes J and Js. The Js genome present in Th. intermedium and Th. ponticum was homologous with E or J genomes, but was quite distinct at centromeric regions, which can strongly hybridize with the S genome DNA probe. Based on GISH results, the genomic formula of Th. intermedium was redesignated JJsS and that of Th. ponticum was redesignated JJJJsJs. The finding of a close relationship among S, J, and Js genomes provides valuable markers for molecular cytogenetic analyses using S genome DNA probes to monitor the transfer of useful traits from Th. intermedium and Th. ponticum to wheat.  相似文献   

13.
Burkitt's lymphoma (BL) is the most frequent non-Hodgkin's lymphoma in children in Argentina. Although epidemiologic studies have linked Epstein-Barr virus (EBV) to more than 90% of African BL cases but to only 10-20% of American and French cases, increased EBV-specific antibody titers were demonstrated in 73% of Argentinian patients with BL. To characterize the relationship between EBV and BL in Argentina, we analyzed paraffin-embedded tissues from 16 cases of BL for the presence of EBV DNA using the polymerase chain reaction (PCR) and in situ hybridization (ISH). PCR analysis showed that only 4 of 16 specimens contained the EBV BamW fragment, and these specimens were all from cases diagnosed in 1984. Results of ISH performed with a specific biotinylated DNA probe against the NotI/PstI fragment of EBV correlated with the PCR findings. EBV sequences were detected with ISH in 70-90% of the tumor cells from the 4 positive cases. These data may suggest an epidemic outbreak of EBV-related BL in 1984 superimposed on sporadic cases of BL, for which EBV may not have been an essential factor. This study also demonstrates the value of using molecular techniques on archival tissue to track epidemiologic trends.  相似文献   

14.
We describe methods for the production of fluorescence in situ hybridization (FISH) probes and the utilization of these probes for the detection of complementary DNA sequences with accuracy and sensitivity for application in both basic research and clinical diagnosis. Due to the frequent use of FISH in many laboratories, it is important to apply the most convenient and reproducible approach. This review describes some of the most recent techniques, and includes versatile, effective and simple methods of probe production and fluorescence in situ hybridization. We also describe methods for the production of region-specific and chromosome-specific DNA probes and hybridization techniques for the visualization of these probes.  相似文献   

15.
We investigated the prognosis of completely resected 119 non-small cell lung cancer patients according to the invaded organs. There was no significant difference in prognosis between T3N0M0 and T3N1M0 patients (5-year survival rate: 34% vs. 38%). However, the prognosis of T3N2M0 patients (5-year survival rate: 11%) was too poor to be regarded as the same category. Therefore, we investigated only T3N0M0 and T3N1M0 patients to assess the contribution of the invaded organs to prognosis. Of the 5 patients with diaphragm invasion, there was no 3-year survivor, and the prognosis of patients with diaphragm invasion was very poor. The chest wall invasion was divided into three parts: parietal pleural invasion, subpleural tissue invasion and intercostal muscular invasion. The 5-year survival rates of patients with such invasion was 35%, 29% and 27%, respectively. The patients with Pancoast tumor had very poor prognosis. T3 factor was heterogeneous, and the prognosis of the patients with T3 tumor was various according to invaded organs.  相似文献   

16.
Biotin was recently applied to detect cellular DNA or RNA. In combination with avidin, streptavidin or antibody, it can be conjugated with fluorescent dye, enzyme, ferritin, or gold. However, emphasis has recently been placed on the false-positive results that are obtained when this probe is used, because endogenous biotin may sometimes interfere with specific signals. Digoxigenin appears to be an interesting alternative because it is present exclusively in Digitalis plants as a secondary metabolite. We discuss in this review the efficiency and the respective advantages and disavantages of these two probes for in situ hybridization, mainly at the electron microscopic level.  相似文献   

17.
Archival tissue specimens are commonly stored as formalin-fixed, paraffin wax-embedded blocks. Formalin fixation facilitates excellent morphological preservation, and the immunoreactivity of many antigens is preserved, but formalin-induced chemical cross-linking of proteins renders them insoluble and inaccessible to standard biochemical extraction and analytical methods. Thus, biochemical analysis of tissue components identified by histochemistry, with the advantage of long-term clinical follow-up, is precluded. We have applied cyanogen bromide cleavage, a technique used routinely for fragmenting proteins for sequencing experiments, to solubilize transferrin polypeptides and glycopolypeptides from formalin-fixed, paraffin wax-embedded rat liver. Cyanogen bromide cleaves protein specifically at methionine residues, yielding a predictable array of polypeptide fragments. Subsequent oligosaccharide analysis of the transferrin glycopolypeptides by anion exchange chromatography confirmed that, in addition to successful release of polypeptide chains, sialylated oligosaccharide structures remained intact after cyanogen bromide cleavage. This approach may have wide applicability to a range of research interests in which correlation of tissue biochemistry with long-term follow-up is advantageous.  相似文献   

18.
Bartonella (formerly Rochalimaea) henselae (Bh) plays a central role in cat scratch disease. A polymerase chain reaction (PCR)-based assay that can detect Bh DNA in formalin-fixed, paraffin-embedded (FF-PE) samples would have utility in the evaluation of processed lymph nodes suggestive of this disorder. Fresh or FF-PE cultures of Bh and related species were analyzed. Thirteen lymph nodes (12 FF-PE and one fresh cell suspension) with necrotizing suppurative granulomatous inflammation and seven FF-PE negative control lymph nodes were also evaluated. PCR was performed using a novel, hemi-nested protocol. Amplified products were analyzed by gel electrophoresis. The fresh and FF-PE Bh cultures showed a specific PCR product with an analytical sensitivity of 0.5 pg bacterial DNA. Seven (54%) of 13 clinical lymph node samples with morphological features suggestive of cat scratch disease also had detectable Bh DNA, whereas none of the seven negative control lymph nodes yielded positive results. We have designed a rapid and sensitive PCR test that can reliably detect Bh DNA in fresh and FF-PE samples. Our findings indicate that this assay has clinical utility in the diagnosis of cat scratch disease.  相似文献   

19.
We report the use of chromosome 21-specific painting probes to analyze early stages of oogenesis in nine trisomy 21 fetuses. The proportion of cells in zygotene and pachytene in the trisomic ovaries ranged from 8 to 70% with a mean of 42% +/- 19 while the comparable values of euploid specimens ranged from 34 to 90% with a mean of 65% +/- 19. The low proportion of pairing cells may be the basis for the ovarian dysgenesis observed in some trisomy infants. Five percent of trisomic pachytene cells exhibited complete asynapsis which is an order of magnitude higher than that observed in euploid cells. A large fraction of the asynaptic cells were atretic which is consistent with the hypothesis of meiotic pairing as a signal for atresia. In addition, the asynaptic cells exhibited asynapsis of chromosomes other than 21, which we interpret as an interchromosomal effect of trisomy 21.  相似文献   

20.
Human insulin-like growth factor I (IGF1) was labeled with 125I and the resulting mixture of iodination isomers was separated by reverse-phase HPLC. Three major radioactive peaks were isolated and identified by sequencing as the expected three monoiodinated species. The ranking of the affinities of the three isomers for the human IGF1 receptor was found to be Tyr24(125I) > Tyr31(125I) > Tyr60(125I). The Tyr31(125I) isomer was shown to have an affinity similar to that of unlabeled IGF1 and is thus the tracer of choice for IGF1. The tracers were stable upon storage at -20 degrees C for at least 3 months.  相似文献   

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