[Thoracic pain in a power athlete].
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Biomedical subjects
Publications and source records attributed to M Werner.
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The formation of cysteine S-conjugates is thought to play an important role in the nephrotoxicity of haloalkenes such as trichloroethene, tetrachloroethene and hexachlorobutadiene. Glutathione S-conjugates formed from these haloalkenes in the liver are processed to the corresponding cysteine S-conjugates, which may be N-acetylated to mercapturic acids and may be accumulated in the kidney. Haloalkene-derived cysteine S-conjugates are also substrates for cysteine conjugate beta-lyases and reactive intermediates are formed in this reaction. The equilibrium between cysteine S-conjugate and mercapturic acid thus influences the extent of beta-lyase dependent bioactivation and subsequently the nephrotoxicity of S-conjugates. In this study, we compared the rates of N-acetylation in vitro and the biotransformation, excretion and nephrotoxicity of S-(1,2-dichlorovinyl)-L-cysteine (1,2-DCVC), S-(2,2-dichlorovinyl)-L-cysteine (2,2-DCVC), S-(1,2,2-trichlorovinyl)-L-cysteine (TCVC) and S-(1,2,3,4,4-pentachlorobutadienyl)-L-cysteine (PCBC) in rats after i.v. injection (40 micromoles/kg). Marked differences in the extent of enzymatic N-acetylation were observed; N-acetylation was most efficient with 2,2-DCVC and least efficient with 1,2-DCVC. In urine, within 48 h, most of the given 2,2-DCVC (77% of the recovered dose) and 1,2-DCVC (92%) were recovered as the corresponding mercapturic acids. In contrast, a higher percentage of cysteine S-conjugate and less of the mercapturic acid were recovered in urine after administration of PCBC and TCVC (50 and 23% of dose as mercapturic acid), respectively. Histopathological examination of the kidneys and urine clinical chemistry showed marked differences in the extent of renal damage. Necroses of the proximal tubules were found after TCVC, PCBC and 1,2-DCVC administration in male, but not in female rats. These differences in nephrotoxicity do not correlate with the balance of acetylation/deacetylation. The higher toxicity observed in male rats may indicate the involvement of other parameters such as uptake mechanisms.
Interphase fluorescence in situ hybridization (FISH) was performed on 15-micron-thick paraffin sections from prostatic carcinomas using a chromosome 7-specific alpha-satellite DNA probe. A confocal laser scanning microscope (CLSM) was used for optical sectioning of the thick sections and reconstruction of 3D images. The number of FISH signals was determined by a gallery of optical sections evaluating only complete nuclei. To investiate the influence of section thickness and truncation and nuclei on scoring results, we compared the FISH data from 15-micron sections with signal counts obtained from 5-micron sections. The latter were evaluated by conventional fluorescence microscopy in the same tumor regions previously defined and marked on the slides. After statistical analysis of spot frequencies in tumor and non-tumorous cells (chi 2 test), we transferred the signal frequencies into a cytogenetic classification (-7, +7, polysomy 7). Based on this classification, most cases showed more than one chromosome 7 aberration type. Trisomy 7 (+7) became apparent in 15-micron thick sections in all 19 tumors, polysomy 7 (> 3 spots) in 18/19 cases, and monosomy 7 (-7) in 13/19 cases. In 5-micron sections, however, trisomy 7 and polysomy 7 were found in only 7/19 and 13/19 cases, respectively, and monosomy 7 in 7/19 cases. When comparing the classification results of tumor cells of the same tumor regions originating either from 5-micron or 15-micron sections, the following discrepancies were noted: in 15-micron sections exclusively, in 12/19 tumors, trisomy 7 was found; in 6/19 cases, polysomy 7; in 8/19 cases, monosomy 7. The high proportion of cases with tumor nuclei expressing only one hybridization signal of chromosome 7 in 15-micron sections could be confirmed as monosomy 7 in five selected cases by double-hybridization using centromere-specific probes for chromosomes 7 and 12. These results demonstrate that numerical chromosome 7 aberrations are more frequently observed in thick (15-micron) paraffin-embedded tissue sections by evaluating only complete nuclei. The use of routine sections (5-micron) for interphase cytogenetic analyses is compromised by a remarkable underestimation of the real chromosome copy numbers.
Interphase cytogenetics is a rapidly developing technique which is usually performed by fluorescence in situ hybridization (FISH). Recently, oligonucleotide-primed in situ synthesis (PRINS) has become established as a method of labelling centromeric regions of chromosomes in metaphase spreads. We tested the suitability of PRINS in detecting the exact copy number of chromosomes 1, 3, 7 and 8 in intact interphase cells of 17 cytological preparations derived from normal and neoplastic tissues. Control procedures consisted in preparation of metaphase spreads of lymphocytes of healthy donors, conventional cytogenetics in some of the specimens, and omission of the primers or Taq polymerase from the reaction mixture. All specimens were additionally examined by FISH and analysed blind by two experienced observers. Both PRINS and FISH revealed a corresponding distribution of hybridization signals for all chromosomes examined in specimens of normal bone marrow (n = 5), normal liver cells (n = 5), three samples of acute nonlymphocytic leukaemia in which conventional chromosome analyses had shown monosomy 7 or trisomy 8, and in four hepatocellular carcinomas that displayed trisomy 1. Overall, statistical analysis revealed no significant difference in the signal distribution between the two techniques. Our results demonstrate that PRINS is as reliable as FISH for detecting chromosome copy numbers in interphase nuclei of intact cells. The PRINS method, however, is easier to perform, faster and less expensive, holding great potential for future applications in diagnostic pathology.
Migration and tissue distribution of immunocompetent cells may be critical prerequisites for efficient immune surveillance. The effect of various concentrations of the mistletoe extract Iscador QuFrF on the locomotory behavior and viability of immunomagnetically isolated human CD4+ and CD8+ T lymphocytes within three-dimensional collagen gels was investigated. Although variation in baseline activities of spontaneously migrating T cells was donor-dependent, a dose-dependent stimulation of the locomotory activity in both CD4+ and CD8+ T cells for noncytotoxic concentrations of Iscador QuFrF (0.25-1.25 micrograms/ml) was detected. The optimal concentration of mistletoe extract and time of maximal response were specific for each donor. As shown by cell tracking and subsequent data analysis, CD4+ T cells exposed to the mistletoe extract displayed a significant increase in mean velocity and time locomoting; total distance migrated was nearly doubled. In contrast, CD8+ T cells showed less pronounced changes in these critical parameters. Cytotoxic effects of the mistletoe preparation on T lymphocytes, which could at least partially be attributed to the induction of apoptosis, were drastically reduced in the presence of fetal calf serum in the culture system. Our data suggest that the direct stimulation of T-cell migration in the presence of mistletoe components may modulate in a dose-dependent manner the system of immune surveillance and recognition in patients under mistletoe therapy.
Controlled activation of non-specific and specific immune defence mechanisms can beneficially manipulate the host's ability to attack malignant cells. In this context, migration and tissue distribution of immunocompetent cells may be prerequisites for an efficient immune surveillance. The effect of various non-cytotoxic concentrations of the Viscum album L. (mistletoe) preparation Iscadore QuFrF on the locomotory activity of immunomagnetically isolated human CD4+ and CD8+ T lymphocytes from healthy donors was investigated. Cellular migration was examined within a three-dimensional collagen matrix. Donor-dependent variations in baseline activities of spontaneously locomoting T cells were accompanied by individual response patterns of T cells from different donors in the presence of various concentrations of mistletoe preparation (0.25-2.5 micrograms/ml). Using the three-dimensional collagen matrix assay an induction of locomotory activity was detected in a highly reproducible fashion although the optimal concentration of mistletoe preparation and the time point of maximal response were individual for each donor. Our data suggest that the direct stimulation of T-cell migration by mistletoe components may modulate the system of immune surveillance and recognition in patients under mistletoe therapy.
Fluorescence in situ hybridization (FISH) is a new technique that allows demonstrating of the bcr/abl gene fusion in bone marrow cells of patients with Philadelphia translocation (Ph)-positive chronic myeloid leukemia (CML). In this study, bone marrow samples of 150 patients were investigated routinely by interphase FISH, cytogenetics, and bone marrow histopathology. In 20 patients with reactive hyperplasia of the granulopoiesis and normal karyotypes, FISH revealed nonspecific bcr/abl fusion signals at a mean frequency of 2.7% of the cells examined. The cutoff level for specific fusion signals was set at three times the standard deviation (9.0%). None of the 29 cytogenetically Ph-negative patients with myeloproliferative disease other than CML had fusion signals exceeding 9%. The mean frequency of specific fusion signals in nontreated patients with CML (n = 59) was 92.7%, and 49.3% in patients with CML who received therapy (n = 42). For diagnosing Ph-positive CML, interphase FISH has been faster, more reliable, and more sensitive than cytogenetics, which was successful in 54 of 59 patients investigated at first diagnosis but only in 27 of 42 patients receiving therapy, and it failed to detect Ph-positive cells in three patients with CML. However, small percentages of less than 9.0% of cells with bcr/abl fusion signals were below the threshold of interphase FISH, thereby limiting its use for detecting minimal residual disease.
Signal amplification in immunohistochemistry via binding of biotinylated tyramine to proteins near the site of peroxidase-labeled antibodies is a promising new technique, but studies investigating a wide range of markers are lacking. The tyramine amplification technique (TAT) was investigated on 85 antibodies using a simple and fast protocol, and TAT results were compared to those obtained with conventional immunohistochemistry. Using TAT, most of the markers could be 5- to 50-fold further diluted and still showed identical staining results compared with standard stainings (maximal 500-fold). However, the variable reactivity of the different markers with TAT underlines the need for individual testing of every antibody to determine the optimal dilution. Some antibodies against cell adhesion molecules could be demonstrated for the first time in archival, formalin-fixed tissue sections. TAT, if carefully evaluated, offers a revolutionary improvement for modern immunostaining, either to increase sensitivity or primary antibody dilutions (cost reduction). From a methodological point of view, immunohistochemistry has not reached its limits by far and TAT is an important progressive step in this developmental process.
PURPOSE: To define the prognostic factors after surgical resection of bile duct carcinomas at the hepatic bifurcation. PATIENTS AND METHODS: The retrospective single-center experience details 151 patients after surgical resection of central bile duct carcinoma performed between 1971 and 1995. Tumor removal was accomplished by resection of the bile duct bifurcation either alone (group I, n = 33), in combination with hepatic resection (group II, n = 77), or combined with hepatic and vascular resection (group III, n = 41). Survival analysis was performed by the Kaplan-Meier method and the relationship between each of the clinicopathologic variables and survival was assessed by the log-rank test. Multivariate results were confirmed using Cox regression. RESULTS: The overall hospital mortality rate was 9.9% and depended on the extent of resection (group 1, 6.1%; group II, 7.8%; group III, 17.1%). After exclusion of hospital deaths, the overall patient survival rate was 28.4% at 5 and 15.5% at 10 years, with a median survival duration of 2.05 +/- 0.23 years. Univariate survival analysis identified tumor size, lymph node metastases, residual tumor stage, and tumor grading as factors with a statistically significant prognostic impact. Survival prognosis was not influenced by the site of the tumor according to the classification of Bismuth and Corlette, extent of resection, International Union Against Cancer (UICC) stage, perineural and vascular invasion, age, or sex. In a multivariate Cox analysis, only lymph node metastases and residual tumor stage proved to be of independent prognostic significance. CONCLUSION: Resection of central bile duct carcinoma is feasible in many patients and a favorable outcome after resection is mainly determined by curative resection and the absence of lymph node metastases.
There is wide consensus that lymphocyte predominance Hodgkin's disease (LPHD) represents a distinct clinicopathological entity of B-cell origin. However, inconsistent results of immunophenotyping studies and low confirmation rates among multi-center trials pose the question of whether LPHD really expresses heterogeneous marker profiles or whether it represents a mixture of morphologically similar entities. Among 2,836 cases reviewed by the German Hodgkin Study Group, immunophenotyping was performed on 1) cases classified or confirmed as LPHD by the reference panel (n = 104) or 2) cases not confirmed as LPHD but classified as classical HD (cHD) within the reference study trial (n = 104). In most cases, immunohistochemistry revealed a phenotype either LPHD-like (CD20+, CD15-, CD30-, CD45+) or cHD-like (CD15+, CD30+, CD20-, CD45-). In 27 cases, the immunophenotype was not fully conclusive. Additional markers for Epstein-Barr virus and CD57 and in situ hybridization for mRNA light chains allowed for a more clear-cut distinction between LPHD and cHD. However, in 25 of 104 cases, immunohistochemistry disproved the morphological diagnosis of LPHD of the panel experts, whereas 13 cases originally not confirmed as LPHD showed a LPHD-like immunopattern. Immunohistochemically confirmed LPHD cases showed a significantly better freedom from treatment failure (P = 0.033) than cHD; this was not observed in the original study classification based only on morphology (P > 0.05). Significantly better survival for LPHD cases improved from P = 0.047 (original study classification) to P = 0.0071 when classified by immunohistochemistry. Our results show that LPHD is a more immunohistochemical rather than a purely morphological diagnosis. Immunophenotyping of HD biopsies suspected of being LPHD is mandatory when a modified therapy protocol, that is, one different from those used in cHD, is discussed.
The understanding of nursing can be seen as a basis for practising care and as a potential for its evolution. This survey aims at analysing registered nurses understanding of care. Using a qualitative approach seventeen nurses were interviewed. The author used 50 picture cards as a help for the interviewees to express their ideas in a narrative interview. Using a semi-structured interview the ideas were examined in more depth. The findings are described in the second part of this article.
One important mechanism by which multidrug resistance is mediated is the mdr1 gene product, P-glycoprotein (Pgp). Even though chemotherapy, in the treatment of high grade central osteosarcoma (hgc-OS), has led to dramatic improvements in survival rate, a certain percentage of patients still show only a poor response to chemotherapy. To further characterize a potential connection between Pgp and chemotherapy as well as the role of Pgp in tumorigenesis of osteosarcoma, we analyzed Pgp-expression in hcg-OS. Immunohistochemistry was performed on 68 hgc-OS samples from 58 patients using the monoclonal antibody JSB-1; in addition, Pgp-expression in normal bone cells was studied in 5 human epiphyseal growth plates. 70.5% of all cases stained positive for P-glycoprotein, while 29.5% of the cases were negative. Cases investigated after chemotherapy showed a higher incidence (82.9%) of positive P-glycoprotein immunostaining than cases prior to chemotherapy (64.4%). The Pgp-expression of 34 biopsies was compared with chemotherapy, as determined at the surgical specimen. In these cases, however, no correlation could be established between P-glycoprotein expression of the biopsy and the later response to chemotherapy. 48.4% of the cases with biopsies, initially positive for Pgp, showed a good response in the surgical specimen, while only 27.2% of Pgp-positive biopsies were later classified as non-responders. In the normally growing skeleton, positive immunostaining was detected in the area of mineralization of epiphyseal growth plates. Osteoclasts, hypertrophic chondrocytes, and cuboidal osteoblasts showed Pgp-expression, while there was a lack of Pgp in the majority of osteocytes and chondrocytes in the resting and proliferating zone. These data therefore suggest that P-glycoprotein expression in hgc-OS resembles, at least in part, the phenotype of active bone cells. These results may explain why P-glycoprotein, by using immunohistochemistry, in biopsies of osteosarcomas is insufficient to predict the response to chemotherapy.
The first part of the essay depicts the results of the literature research on the topic and the development of a research method. This second part describes the author's findings. They fall into the following categories: "understanding the patient's needs", "how nurses see themselves" and "understanding nursing". The interviewees express an understanding of nursing which is client-centered. They describe conflicts which arise from the discrepancy between their understanding and the daily practice of nursing. The author discusses potential sources of conflict and possible solutions.
Antibodies against CD15, -30, and -20 are often used to support morphological diagnosis of Hodgkin's Disease (HD). The classical HD, i.e., the non-lymphocyte-predominance types, are CD15+, CD30+, and CD20- in general. However, the results for CD15 are less clear-cut in many studies, showing up to 40% of classical HD that lack positivity for this maker. Little is currently known about the relevance of antigen expression in relation to clinical outcome in HD. Therefore, the three markers were analyzed in 1751 cases from the German Hodgkin Study Group, using micro-wave epitope retrieval to optimize staining sensitivity. Eighty-three percent of the cases showed a classical immunophenotype (CD15+, CD30+, CD20-), twelve percent lacked CD15 positivity (CD15-, CD30+, CD20-), and five percent showed other combinations. For 1286 cases, clinical follow-up was available, which revealed significant differences for freedom from treatment failure (P = 0.0022) and overall survival (P = 0.0001) between cases with classical immunophenotype and CD15 negativity (CD30+, CD20-). Multivariate Cox regression using the three markers, age, sex, histology, stage, B-symptoms (fever, sweats, weight loss > 10% of body weight), hemoglobin, and erythrocyte sedimentation rate as factors showed that lack of CD15 expression in classical HD is an independent negative prognostic factor for relapses (P = 0.022) and survival (P = 0.0035). In conclusion, immunohistochemistry is able to identify classical HD cases with unfavorable clinical outcome.
Interphase cytogenetics is mostly performed with use of fluorescence in situ hybridization (FISH), using long DNA probes of several hundred or thousand base pairs in length. Recently, oligonucleotide primed in situ labeling (PRINS) was established for staining centromeres and telomeres of chromosomes in metaphase spreads by Taq-polymerase-mediated incorporation of labeled nucleotides. We investigated the use of PRINS in intact interphase cells of various cytologic preparations, targeting chromosomes 1, 8, and 9. Examining cell smears (n = 3), touch preparations (n = 20), and cytospins (n = 11) of non-neoplastic and neoplastic tissues, PRINS was as sensitive and reliable as the FISH method in assessing the exact chromosome number. Aneuploidy in tumor cells was confirmed by double-color PRINS in a part of the specimens. The PRINS reaction, which requires heating of the cell preparations to as high as 96 degrees C, did not affect the cytomorphologic details. Because PRINS is much faster and approximately 10 times less expensive than FISH, this method allows an increased application of interphase cytogenetics in diagnostic cytopathology.
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The minimal substrate for human RNase P consists of the 5' leader sequence, aminoacyl acceptor stem, T-stem and T-loop of tRNA. The sequences corresponding to the D-stem, anticodon stem and loop and variable loop are replaced by a bulge which can be as small as 1 nt, but requires > 4 nt for optimal cleavage by RNase P. We found that a trans construct in which the T loop is opened between G57 and A58 (tRNA numbering system) is still processed by RNase P. The strand that is cleaved can be considered the target RNA while the other strand serves as an External Guide Sequence (EGS). We were also able to delete the nucleotides corresponding to nt 58 to 60 in the T-loop without affecting cleavage of the substrate. We propose that the sequence UUCG or UUCA (nucleotide 55 to 57 in the T-loop) positioned 3' to a double helical region of 12 to 13 basepairs containing a bulge of > 4 nt can form a structure that is recognized by human RNase P. The four nucleotides UUCR probably form a structure that resembles the uridine turn in the Tloop of tRNA. Since recognition by RNase P seems to be independent of the helical sequence, we suggest that this motif can be used for targeting RNA molecules for EGS-directed cleavage by RNase P. Based on these results, several 13-mer EGSs targeted to the 2.1 Kb surface antigen mRNA of hepatitis B virus (HBV) were designed and tested using a co-transcriptional cleavage assay with a 2.1 Kb HBV transcript. Some of these were capable of inducing cleavage of the HBV RNA by RNase P. The use of such small EGSs for the inactivation of various genes will be discussed.
BACKGROUND: Carcinoma in situ (CIS) is regarded as the precursor of all histologic variants of testicular germ cell tumors except spermatocytic seminoma. For a variety of human malignancies, alterations of the p53 tumor suppressor gene have been identified as prognostic factors for a poor clinical course. Discussions of the occurrence of p53 gene alterations in testicular carcinoma have been controversial. Immunohistochemical detection of the p53 oncoprotein has been reported in four of eight CIS cell areas adjacent to mature teratoma. The majority of investigations have failed to demonstrate p53 gene alterations on the DNA level in testicular carcinoma specimens. However, the genetic analysis of testicular carcinoma is complicated by the histologic variety of tumors, resulting in a mixture of subtypes undergoing moleculargenetic analysis. In the present study, CIS cells identified in normal testicular tissue adjacent to different testicular tumors were examined for alterations of the p53 tumor suppressor gene. The authors believed that the detection of p53 alterations in CIS of the testis would not only support the idea of malignant potential in CIS but might also demonstrate the involvement of the p53 tumor suppressor gene in the development of germ cell cancers. METHODS: CIS cells were identified in the normal testicular tissue adjacent to 18 seminomatous and nonseminomatous germ cell tumors by histopathologic criteria and the immunohistochemical staining reaction for placental-like alkaline phos phase, a highly specific marker for testicular CIS. About 20-50 CIS cells per tumor were collected by a microdissection technique and were subjected to RNA. SSCP analysis and additional DNA-sequence analysis. RESULTS: In 12 of 18 cases (66%), RNA-SSCP analysis of the microdissected CIS cells revealed mutational band shifting at the p53 gene locus. In 7 of 18 cases (39%). the results of SSCP analysis were confirmed by DNA sequencing. DNA-sequence analysis revealed missense point mutations in the p53 gene in four cases (exon 5, codons 158, 170, and 176; exon 6, codon 213) and silent mutations in two cases (exon 5, codon 178; exon 6, codon 213). In one case, the identical missense point mutation (exon 5, codon 176) was detected in the CIS cells and also in the associated germ cell tumor. In two of six cases, different mutations were found in the CIS cells and the testicular tumor. In three cases in which DNA sequencing revealed point mutations in CIS cells, alterations of the p53 gene could not be detected in the examination of the associated tumor specimen. CONCLUSIONS: These findings appear to support the concept that malignant biologic characteristics are present in the in situ stage of testicular germ cell tumors. This is the first report demonstrating monoclonal development of a manifested testicular carcinoma from associated CIS cells on the basis of a certain mutational event in the p53 gene sequence. The involvement of p53 gene alterations in precursor cells of testicular carcinoma appears likely.