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W Kühn

Publications and source records attributed to W Kühn.

At least 19 recordsLinked to original sources
PubMed2005

Evaluation of a digital store-and-forward colposcopic system--a pilot study to assess usability for telemedicine.

We evaluated the diagnostic reliability of cervical examination using digital colposcopy compared with conventional binocular colposcopy. A total of 315 patients were examined and diagnosed by a colposcopist on-site. During the colposcopic examination, digital camera images were stored on a PC (median five pictures per patient). A second physician, experienced in colposcopy, re-evaluated the initial diagnostic findings using the stored digital images. The primary and secondary findings in each patient were categorized according to the Rome classification system. There was agreement between the primary and secondary examiners in 69% of cases (kappa=0.60). There was no systematic bias in terms of under- or over-rating. The proportion of non-assessable colposcopic examinations was 9%. Digital colposcopy was reliable and provided advantages in terms of a better follow-up examination and internal quality control of the diagnosis. The pilot study suggests that telecolposcopy may provide better training and further education for physicians and students, and may also improve the diagnostic possibilities in gynaecology.

Adult↗
PubMed2004

Impairment of the antiproliferative effect of glucocorticosteroids by 11beta-hydroxysteroid dehydrogenase type 2 overexpression in MCF-7 breast-cancer cells.

To verify the relevance of 11beta-hydroxysteroid dehydrogenase type 2 (11beta-HSD2) activity in controlling breast-cancer cell growth, we have evaluated the correlation of 11beta-HSD2 expression and antiproliferative effects of glucocorticosteroids (GCs) on breast cancer cell proliferation. We cloned human 11beta-HSD2 cDNA into the expression vector pBK-CMV. The interspersing lac promoter region was deleted, achieving differential translational efficiency. The constructs were stably transfected into wild-type MCF-7 breast-cancer cells possessing almost no oxidative and no reductive 11beta-HSD activity. Low (times 7) and high (times 718) 11beta-HSD2 overexpression was achieved. We compared growth behavior of transfected cells In the presence of GCs to MCF-7 cells transfected with pBK-CMV alone (internal control). The antiproliferative effects of GCs were reversed and total cell growth boosted by overexpression of 11beta-HSD2; about 50 % of the increase in cell proliferation was attained by low 11beta-HSD2 overexpression, while high enzyme overexpression led to an increase in cell growth of about 120 %. Using direct evidence, this study shows 11beta-HSD2 to impair antiproliferative glucocorticosteroid effects, thus acting as an enzymatic shield aggravating breast-cancer cell growth. These results indicate a possible therapeutic role for 11beta-HSD inhibitors in the treatment of breast cancer.

11-beta-Hydroxysteroid Dehydrogenase Type 2↗
PubMed2004

[The suitability of digital colposcopy for telematic applications].

Since carcinoma of the cervix is one of the most common cancers in women, screening of the cervix has acquired considerable importance. Colposcopy is a simple diagnostic method of detecting suspicious changes at an early stage. Shortcomings of this method are its low specificity and high inter- and intra-observer variability. A clinical pilot study was therefore carried out to investigate the advantages of a digital colposcopic system comprising a binocular colposcope coupled to a CCD camera and a computer. The aim of the study was to evaluate the reliability of diagnostic findings of the cervix obtained with digital colposcopy in comparison with standard binocular colposcopy, and to assess its suitability for telematic applications (teleconsultation, telediagnostics, treaching). A total of 315 patients were examined and statistically analysed. The patients were first submitted to a conventional colposcopic examination and a diagnosis was established. During the colposcopic examination camera images were stored on a computer, on the basis of which a second physician experienced in colposcopy reviewed the initial diagnosis. The primary and secondary findings of each patient were classified into 4 categories and compared following the Rome classification system. Agreement between the primary and secondary diagnosis was established in 69% of the cases (kappa = 0.60 +/- 0.03). No bias was observed in terms of under- or overrating. The percentage of non-assessable colposcopic examinations was 9.2%. Digital colposcopy is therefore suitable for reproducing diagnostic findings on the computer, given adequate digital image quality and a suitable classification model. The method has clear advantages with regard to follow-up, internal quality control of the diagnosis, and the training and further education of physicians and students. In the future, telecolposcopy may open up new opportunities in gynaecology.

Adult↗
PubMed2003

No acute impact of haemodialysis treatment on free radical scavenging enzyme gene expression in white blood cells.

OBJECTIVE: Oxidative stress has been implicated in the side-effects caused by haemodialysis (HD) treatment. DESIGN: In the present study we have investigated whether gene expression of the enzymatic defence system provided by cellular glutathione peroxidase (GPx-1), phospholipid glutathione peroxidase (GPx-4), glutathione reductase (GSSG-R), glutathione synthethase (GSH-S), Cu/Zn-superoxide dismutase (SOD-1) and catalase (CAT) is affected by HD. The GPx-1, GPx-4, GSSG-R, GSH-S, SOD-1 and CAT mRNA were determined in white blood cells by quantitative reverse transcriptase-polymerase chain reaction with the LightCycler instrument and transcription elongation factor-2 as reference gene at the start (SD) and immediately after (ED) dialysis treatment (n = 36). In a subgroup (n = 10), messenger RNA (mRNA) expression was determined hourly during a 5 h HD. RESULTS: The expression of GPx-1, GPx-4, GSSG-R, GSH-S, SOD-1 and CAT mRNA was not affected by a single HD treatment. All mRNAs were significantly (P < 0.05) increased in HD patients [median (16. percentiles (perc.); 84. perc.)]: GPx-1: 2.18 (0.89; 3.23); GPx-4: 0.41 (0.26; 0.74); GSSG-R: 0.04 (0.02; 0.10); GSH-S: 0.04 (0.02; 0.08); SOD-1: 0.32 (0.20; 0.62); CAT: 0.12 (0.06; 0.18) when compared with healthy blood donors (GPx-1: 0.91 (0.60; 1.44); GPx-4: 0.27 (0.16; 0.43); GSSG-R: 0.02 (0.01; 0.02); GSH-S: 0.02 (0.02; 0.04); SOD-1: 0.15 (0.10; 0.18); CAT: 0.07 (0.04; 0.16). CONCLUSIONS: These results show that the HD procedure does not acutely affect the antioxidant defence system on the gene level but suggest that the chronic stress caused by uraemia and/or HD may cause gene induction of the enzymatic defence system.

Aged↗
PubMed2002

Rho(0) meson production in the pp-->pppi(+)pi(-) reaction at 3.67 GeV/c.

Total and differential cross sections for the exclusive reaction pp-->pp rho observed via the pi(+)pi(-) decay channel have been measured at p(beam)=3.67 GeV/c. The observed total meson production cross section is determined to be (23.4+/-0.8+/-8) mu b and is significantly lower than typical cross sections used in model calculations for heavy-ion collisions. The differential cross sections measured indicate a strong anisotropy (approximately cos(theta(CM)(rho)) in the rho(0) meson production.

Journal Article↗
PubMed1992

[Results of treatment in vulvar cancer from 1970 to 1990].

From 1970-1990, 159 patients with invasive malignant tumours of the vulva (150 squamous cell carcinomas) underwent surgery at the University Hospitals, department of gynaecology. Heidelberg (1970-1988) and Homburg/Saar (1988-1990). 73% of the patients were more than 60 years old and 3% were less than 40 years old. The mean age was 69 years. 30% of the patients had diabetes mellitus. As a standard therapy, 101 patients had radical vulvectomy with bilateral inguinal node removal in accordance with S. Way. If nodes were found to be positive, the inguinal/pelvic region was irradiated postsurgically with 40-50 Gy. The 5 years survival rate for all patients with vulvar carcinoma was 69%. For early stage carcinomas (pT1, depth of invasion < or = 1 mm) a restricted radical therapy should be considered. 9 patients with early stage carcinomas survived disease-free for a period of 70 months. Significant prognostic differences were noticed if node histology was N- as opposed to N+ (p < 0.001), if depth of invasion was < or = 1 mm as opposed to > 10 mm (p < 0.001), if stage was pT1 as opposed to pT2 to pT4 (p < 0.001) or if lymphangiosis carcinomatosa (p < 0.01) was present or not. Prognostic differences were also noticed, if cytological grading was done in accordance with Broders (p < 0.09). 27 patients had successful reconstructive surgery with local cutaneous or myocutaneous flaps at the time of initial surgery. The median recovery period after radical vulvectomy with bilateral inguinal lymph node excision was 22 days. The median recovery period after radical vulvectomy with bilateral node removal and reconstructive surgery was 25 days. Early recurrence of carcinoma (< or = 6 months after initial therapy) was 5.9%, late recurrence was 12%.

Aged↗
PubMed1992

Human cytomegalovirus in immunoglobulin A nephropathy: detection by polymerase chain reaction.

Human cytomegalovirus (HCMV) has been suspected to participate in the pathogenesis of IgA nephropathy (IgAN). However, with regard to the presence of HCMV in the renal tissue of IgAN, conflicting results have been reported using a variety of different techniques. Renal biopsies of 29 patients with IgAN, of 7 with focal segmental glomerulosclerosis (FSGS) and of 11 normal kidneys were analyzed for the presence of HCMV-DNA using the polymerase chain reaction. HCMV-DNA was detected by hybridization with digoxigenin-labelled probes in 14 of 19 analyzed frozen renal biopsies from patients with IgAN. However, only 1 of 17 renal biopsies of IgAN embedded in paraffin was positive for HCMV-DNA. Furthermore, HCMV-DNA was detected in 4 of 18 frozen normal kidneys but in none of the tissues from patients with FSGS. The present results provide further evidence of an association between the presence of HCMV in renal tissue and IgAN.

Adult↗
PubMed1992

Human cytomegalovirus in rejected kidney grafts; detection by polymerase chain reaction.

Human cytomegalovirus (CMV) infections are frequently associated with graft rejection in the immunosuppressed patients following organ transplantation. Thirty-four tissue samples from rejected kidneys and 18 samples from normal adult kidneys obtained from autopsies were investigated for the presence of CMV-DNA by the polymerase chain reaction (PCR) and by immunohistochemistry. DNA extracted from renal tissues after proteinase K digestion was specifically amplified in 32 cycles using primers which flank a 147 bp DNA fragment of the immediate early CMV gene and analysed by slot-blot hybridization with digoxigenin-labelled detection oligonucleotides. CMV-DNA was detected by PCR in a range from 0.1 fg up to 100 fg in 14 (41%) rejected kidney transplants. Comparative immunohistological analysis revealed presence of CMV in only three biopsies of these rejected kidneys. Furthermore, CMV-DNA was also found in four of 18 (22%) normal donor kidneys. These results reveal that CMV is often present in rejected kidneys and that the infection can be transferred from the donor to the recipient, since the normal adult kidney appears to be a frequent site of latency for CMV. No differences in local immunological changes, characterized by interstitial mononuclear leukocyte infiltration as well as by aberrant expression of HLA-class II antigens and of ICAM1 on proximal tubular epithelial cells, could be detected by further immunohistological analysis between grafted kidneys at late stage of rejection with and without CMV infection.

Adolescent↗