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91.
Endothelial cell transplantation and growth behavior of the human corneal endothelium 总被引:1,自引:0,他引:1
Katrin Engelmann Jürgen Bednarz Matthias Böhnke 《Der Ophthalmologe : Zeitschrift der Deutschen Ophthalmologischen Gesellschaft》1999,96(9):555-562
Background: The human corneal endothelium has a limited proliferative capacity in vivo. Until now it has only been possible to replace
damaged endothelium by transplantation of a donor cornea. After establishing methods for the isolation and in vitro cultivation
of human corneal endothelial cells, transplantation of these cells my be an alternative therapeutic option.
Materials and methods: In this review methods for the in vitro cultivation of human corneal endothelial cells and their transplantation on the Descemet
membrane of donor corneas are described.
Results: In vitro proliferation of human adult corneal endothelial cells was achieved by the development of defined cell culture conditions,
including supplementation of culture medium with specified growth factors and substances. Dependent on the culture conditions,
as well as independent of them, in vitro cultured endothelial cells showed phenotypic changes and different proliferative
behavior. Thus, molecular biological examinations revealed a different expression pattern of growth factor receptors in fibroblast-like
endothelial cells (dedifferentiated) compared to typical endothelial cells (differentiated). Moreover, the proliferative capacity
of the cells differed, dependent on their corneal location. Cells isolated from the peripheral part of donor corneas have
a higher proliferative capacity than cells obtained from the central part. The propagation of corneal endothelial cells in
vitro offered the possibility of their transplantation on donor corneas in an in vitro model. After transplantation, these
cells formed a monolayer whose morphology and cell density depended on the differentiation of the cells. DNA synthesis was
predominantly detectable in cells of the corneal periphery.
Conclusions: Our findings are the basis of the following hypothesis: the periphery of the cornea represents a regenerative zone of the
corneal endothelium. The fact that early after transplantation corneal endothelial cells form a monolayer on the natural extracellular
matrix (ECM), which shows contact inhibition, suggests that inhibitory factors are released by the Descemet membrane that
influence the proliferation of the cells. Further studies on the regulation of the proliferation and differentiation of human
corneal endothelial cells in vitro and after transplantation might offer the possibility to establish a selective procedure
for the treatment of corneal endothelial cell loss in the near future.
相似文献
92.
Zusammenfassung Anhand von Daten aus zwei Bevölkerungsumfragen zur Einstellung gegenüber psychisch Kranken wird untersucht, welchen Einfluss die Variation der Perspektive-die des Befragten selbst versus die der anderen-auf das Befragungsergebnis hat. Wie erwartet fällt das Urteil über psychisch Kranke positiver aus, wenn nach der eigenen Meinung gefragt wird, als wenn man das Urteil der anderen einschätzen lässt. Der Unterschied zwischen beiden Frageformulierungen nimmt mit dem Grad der Schulbildung zu und erreicht bei Personen mit Abitur ein substantiell bedeutsames Ausmass. Darüber hinaus sind die Antworten eindeutiger und pointierter, wenn nach der persönlichen Meinung gefragt wird.
Summary The impact of the change in perspective (i.e. the personal opinion of those questioned versus what they perceive the others' opinion toward the mentally ill to be) on the results of the questionnaire is examined based on data from two population surveys measuring attitudes towards the mentally ill. As expected, the respondents' attitudes towards the mentally ill are more positive if they are asked to give their own opinion. The impact that the variation of the two formulations of these questions has on the respondents increases with their level of education and reaches a substantial amount among those with Abitur. Furthermore, the answers are clearer and more definite if those questioned are asked for their personal opinion.
Résumé L'impact d'un changement de perspective (opinion personnelle comparée à l'opinion générale telle qu'elle est personnellement perçue) est examiné dans le cadre de deux études de population mesurant l'attitude envers les malades psychiques. Comme on pouvait s'y attendre, l'attitude des répondants est beaucoup plus positive lorsqu'il s'agit de leur opinion personnelle. La divergence entre l'opinion personnelle et la perception de l'opinion générale augmente au fur et à mesure que le niveau d'éducation s'accroît. Les réponses sont d'autre part bien plus clairement formulées lorsque les personnes experiment leur opinion personnelle.相似文献
93.
According to the "Population-based cancer register" of the Federal Republic of Germany only malignant neoplasms of the buccal cavity, the pharynx and larynx as well as cancers of the respiratory tract show an increasing rate of incidence and mortality. The molecular mechanisms and etiological factors causing this phenomenon are still little understood despite intensive research work. Recognition between receptors on a cellular level may be mediated by specific amino acid sequences on the level of protein-protein recognition. Additionally, the interactions between cell sugars and the corresponding protein receptor may play a decisive role in development, regeneration and organisation of cells and tissue. The high specificity of the binding of biotinylated neoglycoproteins in tissue sections enables to detect glycohistochemically binding sites for the carbohydrate ligands of the glycosylated carrier protein. The evidence of lectins in squamous cell cancer of the oral cavity, oropharynx, larynx, and hypopharynx has not been established so far. Squamous cell cancer tissue samples of twelve patients with different tumour locations were investigated by incubation of sections of paraffin-embedded samples and application of an avidin-biotin-peroxidase complex for visualisation with synthetic biotinylated neoglycoproteins. Altogether 168 stained sections were evaluated including controls. Pronounced cytoplasmatic staining was seen with the following neoglycoproteins: sialic acid-bovine serum albumin (BSA), glucuronic acid-BSA, N-acetylglucosamine (glcNAc)-BSA, N-acetylgalactosamine (beta-galNAc)-BSA, lactose-BSA, maltose-BSA, mannose-BSA, mannose-6-phosphate-BSA. No corresponding lectins seems to exist for the following investigated sugars: fucoidan, heparin, and the alpha-anomeric form of N-acetylgalactosamine, because no specific staining was seen.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
94.
Matthias C. Angermeyer Dirk R. Schwoon 《Social psychiatry and psychiatric epidemiology》1982,17(1):13-22
Zusammenfassung Mit Hilfe eines Persönlichkeitsfragebogens (Gießen-Test), der von beiden Eltern und dem schizophrenen Kranken bei dessen Entlassung aus der ersten stationären psychiatrischen Behandlung ausgefüllt worden war, wurde die Personenwahrnehmung und damit mittelbar die Beziehung in der Familie untersucht. Über alle drei Selbstbilder und sechs Fremdbilder von insgesamt 28 Familien mit einem schizophrenen Sohn sowie von 29 als Vergleichsgruppe dienenden Familien mit einem chirurgisch kranken Sohn wurde eine Clusteranalyse berechnet, die die Abgrenzung von fünf Clustern erlaubte, von denen zwei vor allem durch Familien mit Schizophrenen und zwei vor allem durch solche mit organisch kranken Söhnen gebildet wurden; ein Cluster war unspezifisch. Ein 2-Jahres-follow-up ergab, daß 13 schizophrene Kranke erneut die Klinik aufsuchen mußten. Es fand sich keine statistisch bedeutsame Beziehung zwischen den untersuchten psychiatrischen und soziodemographischen Parametern und dem Rehospitalisierungsrisiko. Als besonders gefährdet erwiesen sich jedoch Familien, in denen sich nach den Ergebnissen der Clusteranalyse ein Konflikt zwischen Eltern und Sohn um die Definition als Kranker auf dem Hintergrund rigider Normvorstellungen abbildete. Die Übernahme der Krankenrolle durch den Patienten ging hingegen nur in der Hälfte der Fälle mit einer Rehospitalisierung einher, führte also nicht zwangsläufig zur Ausgrenzung aus dem Familienverband. Söhne aus Familien, die als besonders gesund imponierten, aber auch Söhne aus Familien mit dominanten Müttern wurden im Untersuchungszeitraum nicht erneut in die Klinik aufgenommen.
Teil des von der Deutschen Forschungsgemeinschaft unterstützten Projektes Interaktion in Familien mit Schizophrenen 相似文献
Summary Patterns of personal relationships within the families of male schizophrenic patients, and their relationship to clinical course and outcome, were examined by means of a personality questionnaire (Gießen-Test), completed by both parents and by the schizophrenic patient himself at the time of discharge from his first psychiatric in-patient treatment. The test yields scores related to the self-perceptions of the individual and to his perceptions of the other nuclearfamily members. A cluster analysis was performed on all three self-perception scores and six scores of the perceptions the three family members had of each other, for a total of 28 families each with a schizophrenic son and for a control group of 29 families each with a surgically-ill son. This analysis allowed five clusters to be distinguished, two of which consisted predominantly of families with schizophrenic sons and two predominantly of families with surgically-ill sons. The remaining cluster comprised a mixed group. A two-year follow-up showed that 13 schizophrenic patients had been readmitted to hospital. There was no statistically significant relationship between the psychiatric and sociodemographic parameters examined and the re-hospitalization rate. Readmissions were, however, more frequent from families in which the research findings had indicated conflicting mutual perceptions of parents and sons, against a background of rigid notions of normality. Acceptance by the patient of the notion of being ill was associated with re-hospitalization in only about half of the cases, so that it had not necessarily led to rejection by the family unit. No patients were readmitted during the follow-up period from families which had represented themselves as particularly healthy, or from families with dominant mothers.
Teil des von der Deutschen Forschungsgemeinschaft unterstützten Projektes Interaktion in Familien mit Schizophrenen 相似文献
95.
After proctocolectomy with ileal pouch-anal anastomosis (IPAA) patients have increased stool frequency and intermittently
use antidiarrheal medication. In addition to other factors, gastrointestinal transit time (MTT) could influence stool frequency.
The aim of this study was to investigate how MTT changes after IPAA and to study whether MTT has an influence on daily stool
frequency. In a prospective trial MTT was investigated with the lactulose breath test in 12 patients undergoing surgery for
chronic ulcerative colitis (CUC) or familial adenomatous polyposis coli (FAPC) at different stages: before proctocolectomy,
after IPAA with loop ileostomy, and 3 months and 1 year after ileostomy closure. MTT was also measured in 12 patients with
IPAA, 12 patients with subtotal colectomy and ileorectal anastomosis (IRA), and 8 patients with conventional proctocolectomy
and Brooke ileostomy (CPC) several years after surgery. Twelve healthy volunteers served as controls. Before IPAA, MTT was
prolonged in CUC versus FAPC and controls. After restoration of gut continuity MTT was markedly accelerated. After 1 year
MTT was slowed again, though values before proctocolectomy and those in controls were not reached. Several years after surgery
MTT was significantly prolonged in IPAA and IRA versus controls. In CPC, MTT could not be determined by lactulose breath test.
Stool frequency showed an inverse correlation to MTT in IPAA. In conclusion, this study shows that orocecal and oropouch transit
are accelerated in the early postoperative period after (procto)colectomy but prolonged in the long-term course. Adaptation
of the small bowel takes longer than 1 year. Impairment of stool frequency may be partly due to this adaptation. 相似文献
96.
97.
Matthias Grube Katayoun Rezvani Adrian Wiestner Hiroshi Fujiwara Giuseppe Sconocchia Jan J Melenhorst Nancy Hensel Gerald E Marti Larry W Kwak Wyndham Wilson John A Barrett 《Clinical cancer research》2004,10(3):1047-1056
PURPOSE: To investigate potential immunotherapeutic strategies in B lymphocytic malignancies we looked for CTLs recognizing CD19 and CD20 epitopes. EXPERIMENTAL DESIGN: Three CD19 and CD20 peptides binding to HLA-A*0201 were identified and used to detect peptide specific CTLs by a quantitative real-time PCR to measure IFN-gamma mRNA expression in 23 healthy individuals and 28 patients (18 chronic lymphocytic leukemia (CLL), 7 follicular lymphoma, 2 acute lymphocytic leukemia, and 1 large cell lymphoma). Peptide-specific CTLs were expanded in culture with CD40-activated B cells to test lytic activity in three patients. RESULTS: In healthy individuals, CD8+ T-cell responses were detected in one to CD19(74-82), in three to CD20(127-135), and three to CD20(188-196). Seven of 27 patients (6 with CLL) had CD8+ T cells recognizing CD19(74-82). Seven patients responded to CD20(127-135) and three to CD20(188-196). All were CLL patients. CD19(74-82)-specific CTLs from three patients were expanded over 4 weeks. These cells were HLA-A*0201 specific and lytic for peptide-loaded antigen-presenting cells but not to malignant or unpulsed B cells. CONCLUSIONS: CTLs that recognize CD19 and CD20 epitopes exist in healthy individuals and may be increased in CLL patients. They are of low avidity and require high doses of peptide for activation. Strategies to increase T-cell avidity would be necessary for T-cell immunotherapeutic approaches using the peptides studied. 相似文献
98.
Carla M van Herpen Maaike Looman Marijke Zonneveld Nicole Scharenborg Peter C de Wilde Louis van de Locht Matthias A W Merkx Gosse J Adema Pieter H de Mulder 《Clinical cancer research》2004,10(8):2626-2635
The objective of this Phase II study was to evaluate the pharmacodynamic and immune effects of intratumorally administered recombinant human interleukin-12 (IL-12) on regional lymph nodes, primary tumor, and peripheral blood. Ten previously untreated patients with head and neck squamous cell carcinoma were injected in the primary tumor two to three times, once/week, at two dose levels of 100 or 300 ng/kg, before surgery. We compared these patients with 20 control (non-IL-12-treated) patients. Toxicity was high, with unexpected dose-limiting toxicities at the 300 ng/kg dose level. Dose-dependent plasma IFN-gamma and IL-10 increments were detected. These cytokine levels were higher after the first injection than after the subsequent injections. A rapid, transient reduction in lymphocytes, monocytes, and all lymphocyte subsets, especially natural killer cells, was observed, due to a redistribution to the lymph nodes. In the enlarged lymph nodes of the IL-12-treated patients, a higher percentage of natural killer cells and a lower percentage of T-helper cells were found compared with control patients. The same pattern was detected in the infiltrate in the primary tumor. Real-time semiquantitative PCR analysis of peripheral blood mononuclear cells in the peripheral blood showed a transient decrease of T-bet mRNA. Interestingly, the peripheral blood mononuclear cells in the lymph nodes showed a 128-fold (mean) increase of IFN-gamma mRNA. A switch from the Th2 to a Th1 profile in the lymph nodes compared with the peripheral blood occurred in the IL-12-treated patients. In conclusion, in previously untreated head and neck squamous cell carcinoma patients, recombinant human IL-12 intratumorally showed dose-limiting toxicities at the dose level of 300 ng/kg and resulted in measurable immunological responses locoregionally at both dose levels. 相似文献
99.
Regine Schneider-Stock Carsten Boltze Jerzy Lasota Markku Miettinen Brigitte Peters Matthias Pross Albert Roessner Thomas Günther 《Journal of clinical oncology》2003,21(9):1688-1697
PURPOSE: Gastrointestinal stromal tumors (GISTs) represent a distinctive (but histologically heterogeneous) group of neoplasms, the malignant potential of which is often uncertain. To determine the prognostic relevance of p16INK4 alterations in GISTs, we investigated a larger group of GISTs and correlated the genetic findings with clinicopathological factors and patient survival. MATERIAL AND METHODS: We evaluated the methylation status of the promotor by methylation-specific polymerase chain reaction (PCR), the presence of mutations by PCR-SSCP-sequencing, the loss of heterozygosity at the p16INK4 locus (using the c5.1 marker), and the immunohistochemical expression of p16INK4 protein in 43 GISTs in 39 patients. RESULTS: p16INK4 alterations were found in 25 of 43 GISTs (58.1%), with benign, borderline, or malignant GISTs showing no differences in the type and frequency of alteration. p16INK4 alterations were correlated with a loss of p16INK4 protein expression (P <.01). Patients who had tumors with p16INK4 alterations had a poorer prognosis than patients with tumors without such alterations (P =.02). There was a high predictive value for p16INK4 alterations only in the group of benign and borderline GISTs (P <.01) with regard to clinical outcome. Univariate Cox's proportional hazard regression analysis revealed a strong correlation between p16INK4 alterations, tumor size, mitotic index, and overall survival (P <.02), whereas multivariate Cox's analysis confirmed only p16INK4 alterations as an independent prognostic factor. CONCLUSION: We believe that the evaluation of p16INK4 alteration status is a helpful prognosticator, particularly in the benign and borderline groups of GISTs. 相似文献
100.
Loss of beta-catenin expression in metastatic gastric cancer. 总被引:10,自引:0,他引:10
Matthias P A Ebert Jun Yu Juliane Hoffmann Alba Rocco Christoph R?cken Sabine Kahmann Oliver Müller Murray Korc Joseph J Sung Peter Malfertheiner 《Journal of clinical oncology》2003,21(9):1708-1714
PURPOSE: Beta-catenin (beta-catenin) participates in intercellular adhesion and is an integral part of the Wnt signaling pathway. The role of beta-catenin in the pathogenesis of gastric cancer and its metastasis is largely unknown. PATIENTS AND METHODS: Immunohistochemistry and Western blot analysis were used to analyze the expression of beta-catenin in 87 human gastric cancers, in metastasis and cancer cell lines. The beta-catenin and the adenomatous polyposis coli (APC) genes were analyzed for gene mutations. Furthermore, methylation of the beta-catenin promoter in cell lines was assessed by treatment with 5'-azadeoxycytidine and sodium bisulfite genomic sequencing. RESULTS: beta-Catenin expression was present at either the cell membrane or the cytoplasm in 34 of 75 primary gastric cancers. Expression of beta-catenin was significantly more frequent in intestinal-type (P =.0049) and well-differentiated gastric cancers (P <.001). There were no quantitative differences between gastric cancers and the nonmalignant gastric tissues, as determined by Western blot analysis. One of 18 metastatic cancer lesions and four of five gastric cancer cell lines expressed beta-catenin protein. N87 cells, derived from the liver metastasis of a gastric cancer, did not express beta-catenin. Treatment with 5'-azadeoxycytidine restored beta-catenin protein levels in this cell line, which exhibited significantly more 5-methylcytosines in the beta-catenin promoter compared with the other cell lines. CONCLUSION: beta-Catenin expression is lost in a subgroup of primary gastric cancers, is frequently absent in metastases, and exhibits nuclear localization in cancers with either beta-catenin or APC gene mutations. Interestingly, the loss of beta-catenin expression in metastatic gastric cancers may result from hypermethylation of the beta-catenin promoter. 相似文献