Biomedical subjects

A Wille

Publications and source records attributed to A Wille.

At least 19 recordsLinked to original sources

PubMed2006

Fast-track surgery in laparoscopic radical prostatectomy: basic principles.

Fast-track surgery describes innovative treatment concepts ensuring a faster convalescence phase. The aim of this study was to allow hospital discharge 3 days after surgery without additional complications in patients receiving LRPE for localized prostate cancer. Twenty-five patients each were randomized in the study groups to verify if a fast-track regimen could be transferred into clinical routine. The perioperative data, early complications, hospital stay as well as readmission rate were analyzed. The mean postoperative stay was 3.6 days in the fast-track group versus 6.7 days in the conventional group. The overall complications were significantly less in the fast-track procedure. The readmission rate was low and not significant. Patients receiving an LRPE benefit from a suitable fast-track concept. The postoperative hospital stay could be shortened nearly by half with a significantly decreased overall complication rate. Thus, fast-track concepts might contribute to saving resources in the long term. However, more evidence based on larger prospective trials is needed to achieve optimal quality of life for patients perioperatively.

Aged↗

PubMed2006

[Kidney transplantation in childhood and adolescence].

The reasons for end-stage renal disease in pediatric patients differ from adults. The therapy of choice is renal transplantation. A total of 117 children and adolescents were treated with renal transplantation in 2003 in Germany. Immunosuppressive therapy and related comorbidities are the main problems in pediatric patients. The following article provides a summary of transplantation in children, preparation, and follow-up.

Adolescent↗

PubMed2004

Nonmyeloablative stem cell transplantation in metastatic renal cell carcinoma: delayed graft-versus-tumor effect is associated with chimerism conversion but transplantation has high toxicity.

Seven out of 29 patients with metastatic renal cell carcinoma (RCC) considered eligible for allogeneic stem cell transplantation underwent nonmyeloablative stem cell transplantation (NST) from HLA-identical donors. Conditioning comprised cyclophosphamide, fludarabine and antithymocyte globulin. Prolonged mixed chimerism (MC) after engraftment converted to complete donor chimerism (CC) after infusion of donor lymphocytes and/or graft-versus-host disease (GvHD) in six patients. Five patients developed severe GvHD. Two of seven patients had a delayed tumor response after conversion to CC. After a median follow-up of 10 months (4-24 months), 5/7 patients are alive, one in very good partial remission (PR), one with stable and three with progressive disease. One of the seven patients died from sepsis in PR and 1/7 died from rapid tumor progression after sustained MC. None of the 22 nontransplanted patients responded to further therapies. Survival after 1 year was 59% in transplanted and 66% in nontransplanted patients (n.s.). A pooled data analysis from the literature suggests a graft-versus-tumor effect after transplant in patients with metastatic RCC, which becomes effective after chimerism conversion. Available data demonstrate high nonrelapse mortality in these patients. NST in RCC still has to be regarded as an investigational approach requiring careful patients' selection and longer follow-up within clinical studies.

Adult↗

PubMed2004

Proteasome inhibitors modulate chemokine production in lung epithelial and monocytic cells.

Proteasome inhibition has become a target for antitumour and anti-inflammatory therapy. The present study investigated the influence of cysteine proteinase and proteasome inhibitors on chemokine production in lung epithelial cells and monocytic cells. The lung carcinoma cell lines A549, SK-MES, NCI-H727, virus-transformed bronchial epithelial cell line BEAS-2B, primary lung epithelial cells, and the acute monocytic leukaemia cell lines Mono-Mac-6 and THP-1 were incubated with proteasome (N-acetyl-L-leucyl-L-leucyl-L-norleucinal (ALLN), beta-lactone) or cysteine proteinase inhibitor (L-trans-Epoxysuccinyl-Leu-3-methylbutylamide-ethyl ester) and the influence on chemokine production (interleukin-8: IL-8, monocyte chemoattractant protein-1, RANTES) was quantified at protein and mRNA levels. Inhibition of proteasome activity by ALLN and beta-lactone resulted in significantly increased IL-8 secretion (5- to 22-fold). Cysteine proteinase inhibitors did not influence chemokine production. The simultaneous rise in IL-8 mRNA was caused by an increased half-life of mRNA and increased RNA synthesis. Moreover, analysis of transcription factor activation revealed induction of activator protein-1 (c-Jun) activity by proteasome inhibition, whereas nuclear factor-kappaB (p50 and p65) was not activated. The significant increase in IL-8 production after proteasome inhibition was also observed in primary lung epithelial cells and in monocytic cells. In addition, the secreted IL-8 was biologically active as shown by the neutrophil chemotaxis assay. In conclusion, it was shown that proteasome inhibitors stimulate interleukin-8 secretion in lung epithelial cells and monocytic cells, thus recruiting neutrophils.

Analysis of Variance↗

PubMed2003

Tumor type M2 pyruvate kinase expression in metastatic renal cell carcinoma.

The M2 isoenzyme of pyruvate kinase (M2-PK) is specifically expressed in tumor cells (TuM2-PK) and has been detected in the peripheral blood of patients with renal cell carcinoma (RCC). TuM2-PK is not useful as a biological marker in localized RCC. We analysed TuM2-PK in 68 patients with metastatic RCC after initial surgery and prior to or during chemoimmunotherapy of metastases. In 50 patients, the levels of TuM2-PK were measured during chemoimmunotherapy with interleukin-2, interferon-alpha2a and 5-fluorouracil for up to 8 months and were correlated to response as assessed by radiological imaging techniques. TuM2-PK was quantified with a commercially available enzyme linked immunosorbent assay kit using a cut off of 15 kU/l. In 48 of 68 patients (71%), TuM2-PK was elevated above the cut-off. TuM2-PK was significantly higher in G3 tumors than in G2 tumors. In 34 of 50 patients (68%) undergoing chemoimmunotherapy, a positive correlation between TuM2-PK values and response to treatment was observed. Based on these data, we would not recommend the routine clinical use of TuM2-PK in metastatic RCC at this point.

Adult↗

PubMed2003

Elastic properties of 2D colloidal crystals from video microscopy.

Elastic constants of two-dimensional (2D) colloidal crystals are determined by measuring strain fluctuations induced by Brownian motion of particles. Paramagnetic colloids confined to an air-water interface of a pendant drop are crystallized under the action of a magnetic field, which is applied perpendicular to the 2D layer. Using video microscopy and digital image processing we measure fluctuations of the microscopic strain obtained from random displacements of the colloidal particles from their mean (reference) positions. From these we calculate system-size dependent elastic constants, which are extrapolated using finite-size scaling to obtain their values in the thermodynamic limit. The data are found to agree rather well with zero-temperature calculations.

Journal Article↗

PubMed2003

[Improvement of hemostasis in laparoscopic and open partial nephrectomy with gelatin thrombin matrix (FloSeal)].

Long-term follow-up studies have demonstrated that effective local tumor control and long-term tumor-free progression rates can be achieved by nephron-sparing surgery. However, hemostasis is a major issue and the lack of effective means of hemostasis has limited a wider use of the laparoscopic approach to nephron-sparing surgery. Between January 2001 and August 2002, a total of 36 patients with renal cell carcinomas were treated by partial nephrectomies using a two-component tissue sealant (FloSeal). The median age was 55.2 years (range: 34-71 years). Follow-up time was 1-18 months (median: 5.5 months). The tumor diameter ranged from 2 to 5 cm (median: 2.9 cm). Open retroperitoneal surgery was performed in 17 cases and laparoscopic partial nephrectomy in 19 cases. The two-component tissue sealant (consisting of a gelatin matrix with granular and thrombin components) was applied after resection of the tumor and before perfusion of the kidney. The following parameters were recorded: (1) time until complete hemostasis was achieved, (2) decrease in postoperative hemoglobin level, (3) postoperative bleeding, and (4) presence or absence of a perirenal hematoma 24 h and 10 days postoperatively by ultrasound. After application of the tissue sealant for 1-2 min to the moist resection site, hemostasis was immediate in all cases. During the laparoscopic partial nephrectomies, a laparoscopic applicator was used that avoided wasting the tissue sealant within the dead space of the instrument. When reperfusion of the kidney was established, hemostasis was maintained. The decrease in postoperative hemoglobin level ranged from 0.3 to 1.2 points (median: 0.8 points). None of the patients required blood transfusions. There were no cases of postoperative bleeding. An ultrasound examination 24 h and 10 days postoperatively demonstrated the absence of a significant perirenal hematoma. The two-component tissue sealant FloSeal provided immediate and durable hemostasis in open and laparoscopic partial nephrectomies. The tissue sealant may provide a tool to expand the possibilities of laparoscopic nephron-sparing surgery.

Adult↗

PubMed2003

[Renal carcinoma with invasion of the suprahepatic vena cava (Staehler stage III and IV): surgical treatment and results].

The operative treatment of patients with renal cell carcinoma (RCC) and suprahepatic infradiaphragmatic or supradiaphragmatic vena cava invasion (Staehler stage III and IV) is still an interdisciplinary challenge. The potential high complication rate and the enormous operative-technical efforts have to be brought into line with the individual benefit for the patient. In this study, we have retrospectively analyzed the operative results of 24 patients. We have further compared the patients during follow-up and immunotherapy due to metastasis with a control group of 75 patients without vena cava invasion. Perioperative mortality in the 24 patients was 4%. Four patients had metastasis at presentation and 14 further patients developed metastatic disease during median follow-up of 23.5 months. Median survival was 45 months with a 1-, 3-, and 5-year survival rate of 92, 57, and 33%, respectively. In a multivariate analysis, only the presence of metastasis (p=0.002) and marginal immunotherapy (p=0.1), but not vena cava invasion (p=0.259) or a positive lymph node status (p=0.624) were significant predictors of a poor survival. For patients with RCC and suprahepatic infradiaphragmatic or supradiaphragmatic vena cava invasion (Staehler stage III and IV), the combination of an aggressive surgical treatment combined with subsequent immunotherapy in the presence of metastatic disease offers a realistic therapeutic option with reasonable survival rates.

Adult↗

PubMed2003

[Laparoscopic dismembered pyeloplasty with Anderson-Hynes technique].

Because of the minimal invasiveness of the laparoscopic approach, we introduced the laparoscopic dismembered pyeloplasty in our treatment modalities for patients with primary UPJ obstruction. We report on our technique and the results after a median follow-up of more than 2 years. Between August 1997 and September 2002, 52 patients underwent a laparoscopic dismembered pyeloplasty at our institution. All patients had a symptomatic primary PJ obstruction. We prefer the transperitoneal route with laterocolic exposure of the kidney. After preparation and exposure of the ureter and the renal pelvis, we performed in each case the dismembered Anderson-Hynes pyeloplasty with resection of the pelvis and reanastomosis between the ureter and renal pelvis. Intracorporeal suturing and knotting techniques were used exclusively. All procedures could be performed successfully. In no case was conversion to open surgery necessary. The mean operative time was 180 min. Crossing vessels were present in 57% of patients. The mean postoperative hospital stay was 4 days. The first patient had an anastomosis insufficiency, which required laparoscopic repair. The same patient failed in the follow-up. He developed a late recurrence of the stenosis and needed an open repair. In all other patients the obstruction was resolved or significantly improved. The long-term success rate is 98% with a follow-up of 25 months. Our results with laparoscopic dismembered pyeloplasties compare favorably with those achieved by open pyeloplasties with less perioperative morbidity and discomfort. We do believe that laparoscopic dismembered pyeloplasty will be the method of choice in the treatment of UPJ obstruction.

Adolescent↗

PubMed2002

[Radical prostatectomy in clinically localized prostate carcinoma. Pro laparoscopic approach].

Systematic development of laparoscopy during the last decade has led to establishing laparoscopic radical prostatectomy (LRP) as a surgical procedure. On the basis of extensive experience at our center, the advantages of the minimally invasive method are described as well as the problems still in existence. Reduced trauma caused by laparoscopic access in combination with clearly reduced blood loss has resulted in less morbidity after laparoscopic procedures. This is reflected in a shorter postoperative stay in hospital and faster convalescence. LRP as an ambitious and complex procedure has an average complication rate of 12%, which shows that the method has surpassed the stage of experimental surgery. By direct comparison, the costs of LRP are higher than for the open surgical procedure, but on the whole this is economically balanced by the lower morbidity, shorter hospital stay, and faster convalescence. The progress in technology to be expected in the field of laparoscopy will further increase quality, precision, and safety of LRP and thus contribute to the establishment of laparoscopic radical prostatectomy as a surgical method of choice.

Adult↗

PubMed2001

Novel selection criteria for genome scans of complex traits.

Due to their oligogenic inheritance, the identification of susceptibility loci for complex traits by classical selection criteria has not been very successful. One way to address this problem is to identify statistics that measure the effect of more than one locus simultaneously. In the approach described here, a p-value is assigned to a combination of loci under the null hypothesis that none of them is linked to the disease locus. In order to examine the power of this method to detect multiple loci, the Genetic Analysis Workshop 12 general population simulated data set was analyzed using variance component methods. Using the described novel selection criteria resulted in an increase of power, however, a rejection of the null hypothesis has to be interpreted with care.

Analysis of Variance↗

PubMed2001

Diagnostic difficulties before definitive treatment of an extragonadal retroperitoneal germ cell tumor.

A primary extragonadal germ cell tumor of the retroperitoneum was diagnosed in a 47-year-old man without elevated serum alpha-fetoprotein, human chorionic gonadotropin, or lactate dehydrogenase levels. The diagnosis was made by histologic analysis after resection. The patient responded well to a combination of cisplatin, etoposide, and ifosfamide, achieving a partial response with four cycles. Residual tumor resection revealed necrotic tissue only. The patient was alive and disease free 24 months after diagnosis. The diagnostic difficulties of this particular situation are discussed.

Antineoplastic Combined Chemotherapy Protocols↗

PubMed2001

A linkage analysis of sex determination in Bombus terrestris (L.) (Hymenoptera: Apidae).

We constructed a linkage map of Bombus terrestris (Hymenoptera, Apidae) phase unknown. The map contains 79 markers (six microsatellite and 73 RAPD markers) in 21 linkage groups and spans over 953.1 cM. The minimal recombinational size of the B. terrestris genome was estimated to be 1073 cM. Using flow cytometry, the physical size of the haploid genome of B. terrestris was calculated to be 274 Mb. This is the second linkage map for a social insect species. Bombus terrestris has on average five times less recombinational events per kb than the honey bee Apis mellifera. Male haploidy, chromosome size, and eusociality can now be excluded as reasons for the high recombination frequency of Apis mellifera. Finally, the sex determination locus of B. terrestris was placed on the map using bulked segregant analysis.

Animals↗

PubMed2001

Interleukin-6 and transforming growth factor-beta 1 control expression of cathepsins B and L in human lung epithelial cells.

Cathepsins B and L are commonly expressed cysteine proteinases that play a major role in lysosomal bulk proteolysis, protein processing, matrix degradation, and tissue remodeling. Cathepsins are also implicated in tumor progression and metastasis, tissue injury, and inflammation. Cells at sites of inflammation often show upregulation and secretion of cathepsins. The regulation of cathepsin expression by inflammatory mediators is not well understood. The aims of this study were to investigate the effect of the cytokines interleukin-1 beta (IL-1 beta), IL-6, IL-10, transforming growth factor-beta 1 (TGF-beta 1), and hepatocyte growth factor (HGF) on expression of cathepsin B and cathepsin L mRNA (quantitative RT-PCR), on protein expression (ELISA, Western blot), and also on enzymatic activity of cathepsins B and L. Investigations were performed using the human lung epithelial cell line A-549. IL-6 was found to induce a concentration-dependent increase in mRNA expression, protein concentration, and enzymatic activity of cathepsin L. Cathepsin B mRNA and protein expression were not affected by IL-6. In contrast, TGF-beta 1 decreased the amount of cathepsin L mRNA and cathepsin B mRNA. At protein level, it was shown that TGF-beta 1 clearly reduced the concentration of cathepsin L but not cathepsin B. The cytokines IL-1 beta, IL-10, and HGF were found to exert no effect on cathepsin B and L expression. In conclusion, these results are the first to show that IL-6 and TGF-beta 1 have opposite effects on the regulation of expression of cathepsins B and L in A-549 human lung epithelial cells. The proinflammatory cytokine IL-6 induced an upregulation of cathepsin L, whereas TGF-beta 1 suppressed cathepsin B and L expression. Further studies are needed to clarify the mechanism that affects cathepsin B and L expression.

Cathepsin B↗

PubMed2001

Trimming, weighting, and grouping SNPs in human case-control association studies.

The search for genes underlying complex traits has been difficult and often disappointing. The main reason for these difficulties is that several genes, each with rather small effect, might be interacting to produce the trait. Therefore, we must search the whole genome for a good chance to find these genes. Doing this with tens of thousands of SNP markers, however, greatly increases the overall probability of false-positive results, and current methods limiting such error probabilities to acceptable levels tend to reduce the power of detecting weak genes. Investigating large numbers of SNPs inevitably introduces errors (e.g., in genotyping), which will distort analysis results. Here we propose a simple strategy that circumvents many of these problems. We develop a set-association method to blend relevant sources of information such as allelic association and Hardy-Weinberg disequilibrium. Information is combined over multiple markers and genes in the genome, quality control is improved by trimming, and an appropriate testing strategy limits the overall false-positive rate. In contrast to other available methods, our method to detect association to sets of SNP markers in different genes in a real data application has shown remarkable success.

Case-Control Studies↗

PubMed2001

Phylogenetic and functional heterogeneity of sediment biofilms along environmental gradients in a glacial stream.

We used in situ hybridization with fluorescently labeled rRNA-targeted oligonucleotide probes concurrently with measurements of bacterial carbon production, biomass, and extracellular polymeric substances (EPS) to describe the bacterial community in sediments along a glacial stream. The abundance of sediment-associated Archaea, as detected with the ARCH915 probe, decreased downstream of the glacier snout, and a major storm increased their relative abundance by a factor of 5.5 to 7.9. Bacteria of the Cytophaga-Flavobacterium group were also sixfold to eightfold more abundant in the storm aftermath. Furthermore, elevated numbers of Archaea and members of the Cytophaga-Flavobacterium group characterized the phylogenetic composition of the supraglacial ice community. We postulate that glacial meltwaters constitute a possible source of allochthonous bacteria to the stream biofilms. Although stream water temperature increased dramatically from the glacier snout along the stream (3.5 km), sediment chlorophyll a was the best predictor for bacterial carbon production and specific growth rates along the stream. Concomitant with an increase in sediment chlorophyll a, the EPS carbohydrate-to-bacterial-cell ratio declined 11- to 15-fold along the stream prior to the storm, which is indicative of a larger biofilm matrix in upstream reaches. We assume that a larger biofilm matrix is required to assure prolonged transient storage and enzymatic processing of allochthonous macromolecules, which are likely the major substrate for microbial heterotrophs. Bacteria of the Cytophaga-Flavobacterium cluster, which are well known to degrade complex macromolecules, were most abundant in these stream reaches. Downstream, higher algal biomass continuously supplies heterotrophs with easily available exudates, therefore making a larger matrix unnecessary. As a result, bacterial carbon production and specific growth rates were higher in downstream reaches.

Archaea↗

PubMed2000

Selecting SNPs in two-stage analysis of disease association data: a model-free approach.

For large numbers of marker loci in a genomic scan for disease loci, we propose a novel 2-stage approach for linkage or association analysis. The two stages are (1) selection of a subset of markers that are 'important' for the trait studied, and (2) modelling interactions among markers and between markers and trait. Here we focus on stage 1 and develop a selection method based on a 2-level nested bootstrap procedure. The method is applied to single nucleotide polymorphisms (SNPs) data in a cohort study of heart disease patients. Out of the 89 original SNPs the method selects 11 markers as being 'important'. Conventional backward stepwise logistic regression on the 89 SNPs selects 7 markers, which are a subset of the 11 markers chosen by our method.

Algorithms↗

PubMed1999

[Bioresonance therapy (biophysical information therapy) in stuttering children].

This study tried to investigate whether bioresonance therapy could have a beneficial effect in stuttering children of school age who showed no progress under other therapies. The 14 patients, age 9-18 years, were randomized in two groups. The first received 10 sessions of bioresonance, the second continued with speech therapy. In the second phase of the study the first group received speech therapy while the second was treated by bioresonance. The intensity of the stuttering was measured at the beginning, at mid-term and at the end of the 9 months experiment. Various established methods were used for that purpose. It was not possible to demonstrate any improvement of the stuttering during or after either of the two therapies. This study showed how difficult it is to investigate stuttering scientifically. It turned out that in reality there is a lack of precise differential diagnosis. This means that true stuttering can hardly be distinguished from other speech disturbances and is under the influence of countless external factors.

Adolescent↗