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Biomedical subjects

H Krause

Publications and source records attributed to H Krause.

At least 19 recordsLinked to original sources

Methylation of tumour suppressor genes APAF-1 and DAPK-1 and in vitro effects of demethylating agents in bladder and kidney cancer.

To examine the significance of the methylation level of the p53 target and tumour suppressor genes apoptotic protease activating factor-1 (APAF-1) and death-associated protein kinase-1 (DAPK-1) in 80 microdissected tumour samples from transitional cell carcinoma (TCC) of the bladder and 80 tumour samples from clear-cell renal cell carcinoma (RCC) as well as from non-tumourous bladder and kidney tissue. Growth-inhibitory effects of the demethylating agents 5-Aza-2'-deoxycytidine (5-Aza-CdR) and zebularine were investigated in TCC and RCC cell lines. The methylation frequency of APAF-1 (DAPK-1) was 100% (77%) in TCC and 100% (33%) in RCC. The methylation levels of APAF-1 could differentiate between the individual tumour stages in TCC as well as in RCC. The APAF-1 methylation levels in RCC were significantly higher in tumours larger than 4 cm and in high-grade tumours. The methylation frequencies in normal tissue for APAF-1 (DAPK-1) were 11% (8%) in bladder tissue and 9% (5%) in kidney tissue. The growth-inhibitory effect of the demethylating agents in TCC (RT4, T24) and RCC (A498, ClearCa-5) cell lines resulted in a 17-132% prolongation of the doubling time (DT). In RCC cell lines, zebularine was superior to 5-Aza-CdR in achieving a DT prolongation. Quantitative real time RT-PCR detected a re-expression of mRNA transcripts of APAF-1 or DAPK-1. In conclusion, demethylating agents effectively retard growth of TCC and RCC cell lines. Methylation level analysis of specific genes has the potential for further tumour characterisation in TCC and RCC.

Aged↗

Interleukin-1 beta contributes to the upregulation of kappa opioid receptor mrna in dorsal root ganglia in response to peripheral inflammation.

During local painful inflammation, axonal transport of opioid receptors from dorsal root ganglia toward the periphery is increased, associated with a higher receptor density and enhanced efficacy of opioid analgesics at the injured site. To examine whether this increase is related to transcription, mRNA of the kappa opioid receptor in lumbar dorsal root ganglia was quantified by real time light cycler polymerase chain reaction. In dorsal root ganglia of naive rats, kappa opioid receptor mRNA expression was three-fold higher than previously shown for delta opioid receptor and two times lower than mu opioid receptor mRNA, respectively. After induction of unilateral paw inflammation by Freund's complete adjuvant, kappa opioid receptor mRNA was significantly upregulated with a peak at 12 h in ipsilateral dorsal root ganglia. This effect could be mimicked by intraplantar injection of the proinflammatory cytokine interleukin-1 beta. Kappa opioid receptor mRNA upregulation lasted longer in interleukin-1 beta-treated rats compared with Freund's complete adjuvant-treated rats. Furthermore, a significant increase in kappa opioid receptor positive neurons was detected by immunohistochemistry 24 h after local injection of Freund's complete adjuvant or interleukin-1 beta. In Freund's complete adjuvant-induced inflammation, kappa opioid receptor upregulation was blocked by treatment with interleukin-1 receptor antagonist without changing the leukocyte infiltration in the paw. In conclusion, kappa opioid receptor mRNA and protein in dorsal root ganglia are upregulated in response to peripheral inflammation. This effect can be mimicked by a single local injection of interleukin-1 beta, and Freund's complete adjuvant-induced upregulation in kappa opioid receptor mRNA and protein can be prevented by treatment with interleukin-1 receptor antagonist. These data suggest that the peripheral production of the proinflammatory cytokine interleukin-1 beta is a specific inducer of kappa opioid receptor expression in the dorsal root ganglia.

Animals↗

Frequent epigenetic inactivation of p53 target genes in seminomatous and nonseminomatous germ cell tumors.

Hypermethylation of tumor-suppressor genes has been implicated in the pathogenesis of human cancers. This study was designed to examine the methylation profiles of a selected group of p53 target genes (APAF-1, CASP-8, DAPK-1, IGFBP-3) and to correlate the findings with the histopathological characterization of testicular germ cell tumors (TGCT). Promoter methylation status was analysed by highly sensitive real-time methylation-specific PCR in 46 primary TGCTs (26 seminomas and 20 nonseminomas) and 15 normal testicular tissue samples. APAF-1 methylation was detected in all of the seminomatous and nonseminomatous TGCTs as well as in 60% of normal testicular tissue. Methylation of DAPK-1 was frequent in seminomas (50%) and nonseminomas (20%), but not in normal testicular tissue (6%). The degree of DAPK-1 methylation correlated with the clinical stage of the disease (P=0.05) and was useful in differentiating seminomatous from nonseminomatous, and malignant from nonmalignant testicular tissue (P=0.04 and 0.02, respectively). The APAF-1 methylation index achieved a highly significant differentiation between seminomatous or nonseminomatous tissue and nonmalignant testicular tissue (P=0.0001). In testicular tumorigenesis, promoter methylation of specific p53 target genes occurs at early stage but to varying degrees. Methylation also occurs in normal testicular tissue, which is in contrast to findings in other urogenital malignancies. Further studies will be necessary to determine whether the methylation level may be used as marker for risk estimation, especially in clinical stage I disease.

Apoptosis Regulatory Proteins↗

Quantitative real-time RT-PCR of CD24 mRNA in the detection of prostate cancer.

BACKGROUND: Gene expression profiling has recently shown that the mRNA for CD24 is overexpressed in prostate carcinomas (Pca) compared to benign or normal prostate epithelial tissues. Immunohistochemical studies have reported the usefulness of anti-CD24 for detecting prostate cancer over the full range of prostate specimens encountered in surgical pathology, e.g. needle biopsies, transurethral resection of prostate chips, or prostatectomies. It is a small mucin-like cell surface protein and thus promises to become at least a standard adjunctive stain for atypical prostate biopsies. We tested the usefulness of real-time RT-PCR for specific and sensitive detection of CD24 transcripts as a supplementary measure for discriminating between malignant and benign lesions in prostatic tissues. METHODS: Total RNA was isolated from snap-frozen chips in 55 cases of benign prostatic hyperplasia (BPH) and from frozen sections in 59 prostatectomy cases. The latter contain at least 50% malignant epithelia. Relative quantification of CD24 transcripts was performed on the LightCycler instrument using hybridization probes for detection and porphobilinogen deaminase transcripts (PBGD) for normalization. RESULTS: Normalized CD24 transcript levels showed an average 2.69-fold increase in 59 Pca-cases (mean 0.21) when compared to 55 cases of BPH (mean 0.08). This difference was highly significant (p < 0.0001). The method has a moderate specificity (47.3%) but a high sensitivity (86.4%) if the cutoff is set at 0.0498. CD24 expression levels among Pca cases were not statistically associated with the tumor and lymph-node stage, the grading (WHO), the surgical margins, or the Gleason score. CONCLUSION: The present study demonstrates the feasibility of quantitative CD24 RNA transcript detection in prostatic tissues even without previous laser microdissection.

Adenocarcinoma↗

Deairing of the venous drainage in standard extracorporeal circulation results in a profound reduction of arterial micro bubbles.

OBJECTIVE: Standard extracorporeal circulation (ECC) remains the staple procedure for cardiac surgeons. Despite modern membrane oxygenators and arterial filters micro bubbles are regularly detected in the arterial line. We investigated whether initial deairing of the venous drainage during connection can reduce the quantity and size of micro bubbles on the arterial side. METHODS: 12 patients underwent isolated coronary artery revascularization with conventional ECC using a two-stage venous catheter and an open, passive venous return into a reservoir. In 6 patients (Control) the venous catheter was routinely connected to the venous line, thereby accepting moderate incorporation of air. In another 6 patients (deaired) the catheter was connected avoiding any visible air entrapment. A bubble counter was used to detect the number and size of any micro bubbles in the arterial line of the ECC. The total number of bubbles as well as the number of bubbles of different sizes was assessed directly after initiation of ECC and during the first 60 sec. RESULTS: All patients had an uneventful surgery with a normal postoperative course. In the Control group a considerable number of bubbles of all sizes occurred initially and after 60 sec. In contrast, very few bubbles were detected in the deaired group. CONCLUSION: Incorporated venous air inevitably reaches the arterial side of the ECC. As deairing of the venous line is a simple and effective manoeuvre to significantly reduce the amount of micro bubbles on the arterial side, we recommend and perform routine deairing in all our patients.

Cardiac Surgical Procedures↗

Kinetic fluorescence RT-PCR is highly sensitive for detection of germ-cell-tumor-specific transcripts in peripheral blood.

The aim of our study was to determine whether conventional staging in patients with testicular germ-cell-tumors (GCT) could be supplemented by quantification of beta-human choriogonadotropin mRNA levels in peripheral blood using kinetic fluorescence RT-PCR. Blood samples from 41 patients with GCT of different clinical stages (CS) were pre-therapeutically examined by kinetic fluorescence RT-PCR with the LightCycler for beta-human chorionic gonadotropin (beta-HCG) mRNA expression levels. The controls comprised of samples taken from patients 3 months after treatment, from patients with inflammatory testicular diseases or non-germ-cell-tumors and from healthy males (n=66). Six positive results [cut-off level: normalized beta-HCG mRNA (Nbeta-HCG) >400 relative gene expression (RGE)] were found in controls (specificity 90.9%, 95% CI: 76.9-97.3%). The overall ratio of positive PCR results in the group of GCT patients was 82.92% (34/41) (CS I 18/23, CS IIa-b 6/7, CS >IIb 10/11) (sensitivity 82.9%, 95% CI: 65.1-91.2%). The average Nbeta-HCG level in patients with clinical stage I tumors was 63772.0+/-125720.5 (mean +/- standard deviation) relative gene expression (RGE), 35076.0+/-52253.5 RGE in those with CS IIa-b tumors and 87298.3+/-120895.3 RGE in those with CS >IIb tumors. Kinetic fluorescence RT-PCR for tumor-specific gene products is, in contrast to qualitative RT-PCR, a promising approach to improve conventional staging in clinical low-stage testicular germ-cell-tumors. With high specificity, its sensitivity is higher than that of the corresponding serum tumor marker (82.92% vs 48.72%).

Biomarkers, Tumor↗

Rapid upregulation of mu opioid receptor mRNA in dorsal root ganglia in response to peripheral inflammation depends on neuronal conduction.

S.c. painful inflammation leads to an increase in axonal transport of opioid receptors from dorsal root ganglia (DRG) toward the periphery, thus causing a higher receptor density and enhanced opioid analgesia at the injured site. To examine whether this increase is related to transcription, the mRNA of Delta- (DOR) and mu-opioid receptor (MOR) in lumbar DRG was quantified by real time Light Cycler polymerase chain reaction (LC-PCR), and correlated to ligand binding in DRG and sciatic nerve. In normal DRG, DOR mRNA was seven times less abundantly expressed than MOR mRNA. After induction of unilateral paw inflammation, mRNA content for DOR remained unchanged, but a bi-phasic upregulation for MOR mRNA with an early peak at 1-2 h and a late increase at 96 h was found in ipsilateral DRG. As no changes were observed in DRG of the non-inflamed side, this effect was apparently not systemically mediated. A significant increase in binding of the MOR ligand DAMGO was detected after 24 h in DRG, and after early and late ligation in the sciatic nerve, indicating an enhanced axonal transport of MOR in response to inflammation. The early increase in MOR mRNA could be completely prevented by local anesthetic blockade of neuronal conduction in sciatic nerve. These data suggest that mRNA of the two opioid receptors DOR and MOR is differentially regulated in DRG during peripheral painful inflammation. The apparently increased axonal transport of MOR in response to this inflammation is preceded by upregulated mRNA-transcription, which is dependent on neuronal electrical activity.

Anesthetics, Local↗

Detection of germ-cell-tumor-specific gene products in peripheral blood by immunomagnetic tumor cell enrichment followed by RT-PCR.

Therapeutic procedures in patients with testicular germ cell tumors (GCT) are determined by the histopathology of the primary tumor and the tumor extension. The aim of our study was to determine whether conventional staging could be supplemented by combining enrichment of disseminated testicular GCT cells from peripheral blood with subsequent detection of germ-cell-specific gene products. Blood samples from 46 patients with GCT of different clinical stages (CS) were examined by RT-PCR before therapy and >/=8 weeks thereafter for alpha-fetoprotein, beta-human chorionic gonadotropin and germ-cell-specific alkaline phosphatase mRNA. In addition, we performed titration experiments to evaluate whether the sensitivity can be improved by previous immunomagnetic tumor cell enrichment with anti-epithelial HEA-125 microbeads. No positive results were found in controls (n=15; specificity 100%). The overall ratio of positive PCR results in the group of patients with GCTs was 28.26%. The ratio was 35.7% for CS >IIb (n=5/14 patients), 20.0% for CS IIa-b (n=4/20) and 33.3% for CS I (n=4/12). FACS analysis in titration experiments with GCT cell lines showed that previous immunomagnetic tumor cell enrichment achieved a significant increase ranging up to 185.6 times the initial ratio and thus improved the measuring conditions for detection of tumor-specific transcripts. The sole qualitative RT-PCR of tumor-specific gene products in peripheral blood is not sensitive enough to improve staging in GCT patients. Immunomagnetic enrichment of GCT cells in peripheral blood seems a promising approach for increasing the sensitivity of RT-PCR.

Calcium-Binding Proteins↗

Measurement of spin-correlation parameters ANN, ASS, and ASL at 2.1 GeV in proton-proton elastic scattering.

At the Cooler Synchrotron COSY/Jülich spin-correlation parameters in elastic proton-proton (pp) scattering have been measured with a 2.11 GeV polarized proton beam and a polarized hydrogen atomic beam target. We report results for A(NN), A(SS), and A(SL) for c.m. scattering angles between 30 degrees and 90 degrees. Our data on A(SS)--the first measurement of this observable above 800 MeV--clearly disagrees with predictions of available pp scattering phase-shift solutions while A(NN) and A(SL) are reproduced reasonably well. We show that in the direct reconstruction of the scattering amplitudes from the body of available pp elastic scattering data at 2.1 GeV the number of possible solutions is considerably reduced.

Journal Article↗

[Molecular diagnostics in urologic oncology. Detection of nucleic acids in urine samples].

The goal of molecular diagnostics in oncology is the early diagnosis of malignant disease processes during initial work-up or as part of follow-up. Body fluids serve as the primary material for non-invasive diagnostic methods. Besides actual tumor cells, the examination of urine can yield evidence of secreted proteins or even free nucleic acids. In principle, all of the methods available for the detection of tumor markers in tissue or blood samples can be successfully applied to the examination of urine samples. However, molecular biological examination of urine samples is associated with important problems because the cells in such samples are exposed to significant degradation and regression effects and because certain components of the urine act to inhibit the polymerase chain reaction. The present overview discusses the respective strengths and weakness of the available technology as applied to the diagnosis of urologic malignancies. Experimental studies conducted to date have reported high sensitivities and specificities for molecular diagnostics using urine samples. It is important to note that not only carcinomas of the urinary bladder can be diagnosed from material obtained in urine samples: in fact, the method can be used to diagnose entities such as renal cell and prostate carcinomas and, due to renal filtration of DNA, even non-urologic malignancies. The diagnostic application of these methods, however, remains in an experimental stage and must still clear several hurdles before becoming available for routine clinical use.

Biomarkers, Tumor↗

[Diagnosis and therapy of the traumatic retrosternal dislocation of the sternoclavicular joint in childhood. A case report].

Traumatic posterior dislocation of the sternoclavicular joint is a rare injury, most commonly occurring in childhood. Computed tomography should be performed on all patients with suspected or established injuries of the sternoclavicular joint to ensure differentiation between fracture and dislocation. Tridimensional computed tomography provides the best imaging for describing and classifying the lession. After closed repositioning, transarticular Kirschner wires were used for stabilisation.

Accidents, Traffic↗

"Onco-tese": testicular sperm extraction in azoospermic cancer patients before chemotherapy-new guidelines?

OBJECTIVES: To examine the usefulness of pretreatment testicular sperm extraction because some patients have tumor-induced azoospermia. In view of the high cure rates for testicular germ cell tumors and malignant lymphomas, increasing clinical importance is attached to protecting fertility. High-dose cytostatic therapy may be expected to cause long-term infertility. Thus, the standard procedure for fertility protection is cryopreservation of ejaculated spermatozoa before therapy. METHODS: Contralateral testicular biopsies were taken from 14 azoospermic patients with malignant testicular germ cell tumors. In addition, 17 patients with malignant lymphomas underwent unilateral (n = 6) or bilateral (n = 11) testicular biopsy. The tissue specimens were cryopreserved, and the histologic workup was performed at the same time. RESULTS: Of the 14 patients with malignant testicular germ cell tumors, 6 had spermatozoa in their testicular biopsies. Sertoli cell-only syndrome was found in 5 patients, and 3 had maturation arrest without detection of spermatozoa. Successful sperm recovery was possible in 8 of the 17 patients with malignant lymphoma, 4 had Sertoli cell-only syndrome, and 5 had maturation arrest. None of the patients had evidence of secondary wound healing or treatment delay because of the testicular biopsy. CONCLUSIONS: Our results show that testicular sperm extraction is a useful technique for obtaining spermatozoa before cytotoxic therapy in azoospermic cancer patients. This procedure should be considered as an option for fertility preservation in azoospermic cancer patients, because high cumulative cytostatic doses can cause irreversible fertility alterations.

Antineoplastic Agents↗

Accumulation of S(+) enantiomer in human beings after general anaesthesia with isoflurane racemate.

BACKGROUND AND OBJECTIVE: Isoflurane is a chiral, volatile anaesthetic with low metabolic rate (0.17%) that is routinely administered in its racemic form. Knowledge about the distribution of the enantiomers in human beings may give some important information about the understanding of the mechanisms of volatile anaesthetics. METHODS: Blood samples were drawn immediately after tracheal extubation and daily up to 8 days postoperatively from patients undergoing general anaesthesia with isoflurane racemate. The enantiomer enrichment of isoflurane was determined by headspace gas chromatography-mass spectrometry. RESULTS: At all time points, there was a statistically significant accumulation of the S(+) enantiomer in blood, especially at days 2 (52.01%) and 7 (52.1%). Separate analysis of obese patients or in a small group of patients with co-existing lung disease did not show any difference to the total population. In addition, duration of anaesthesia did not influence the enantiomer concentrations. CONCLUSIONS: We suggest that a slower association and dissociation rate is responsible for the S(+) enrichment.

Aged↗

Quantification of telomerase activity, porphobilinogen deaminase and human telomerase reverse transcriptase mRNA in testicular tissue - new parameters for a molecular diagnostic classification of spermatogenesis disorders.

The aim of the study was to evaluate the quantitative detection of human telomerase reverse transcriptase (hTERT) mRNA and telomerase activity as new molecular diagnostic parameters for a subclassification of spermatogenesis disorders. Telomerase activity was detected by a quantitative telomerase PCR ELISA, and hTERT mRNA expression was quantified by fluorescence real-time RT-PCR in a LightCycler in cryopreserved testicular tissue specimens. This was paralleled by a histological workup. The discriminant analysis showed that detection of normalized hTERT expression was able to correctly classify 89.0% of the investigated tissue specimens into the subgroups of full spermatogenesis, maturation arrest or Sertoli-cell-only syndrome. In contrast, discriminant analysis revealed an only 58% accuracy of telomerase activity for the investigated tissue specimens. This study shows that the quantification of hTERT expression in testicular tissue by real-time fluorescence RT-PCR is well suited for correctly classifying spermatogenesis disorders and proved to be markedly superior to the determination of telomerase activity.

Biopsy↗

Determinants of fat mass in prepubertal children.

The aim of the present study was to compare variables of metabolism, physical activity and fitness to body composition in normal and overweight children in a cross-sectional study design. Body composition was assessed by anthropometric measurements and bioelectrical impedance analysis in forty-eight prepubertal children (age 5-11 years, thirteen normal-weight, thirty-five overweight). Total energy expenditure (EE) was measured by combination of indirect calorimetry (for measurement of resting EE) and individually calibrated 24 h heart-rate (HR) monitoring. Activity-related EE and physical activity level (PAL) were calculated. Time spent with min-by-min HR>FLEX HR was also used as a marker of moderate habitual and vigorous activities. Aerobic fitness (O2 pulse (O2 consumption:HR at submaximal steady-state heart rate), submaximal O2 consumption (VO2submaximal), RER at a HR of 170 beats per min) was determined by bicycle ergometry. Muscle strength of the legs (maximal isometric strength of musculus quadriceps and of musculus ischiocruralis (Fa max and Fb max respectively)) was measured by computer tensiometry. When compared with normal children, overweight children had higher skinfold thicknesses (sum of skinfold thicknesses at four sites +160 %), fat mass (+142 %), waist (+24 %) and hip circumferences (+14 %), resting EE (+13 %) and RER (+5 %). No significant group differences were found for fat-free mass, muscle mass, total EE, activity-related EE, PAL, HR>FLEX HR, VO2submaximal, O2 pulse, Fa max and Fb max as well as the fat-free mass- or muscle mass-adjusted values for resting EE, aerobic fitness and muscle strength. When compared with normal children, overweight children had a lower measured v. estimated resting EE (Delta resting EE) and spent more time watching television. There were positive relationships between fat-free mass(x) and resting EE(x), total EE(y), aerobic fitness(y) and muscle strength(y), but only Delta resting EE(x) and HR>FLEX HR(x) correlated with fat mass(y). In a stepwise multivariate regression analysis resting EE adjusted for fat-free mass and Delta resting EE were significant determinants of % fat mass and explained 29.7 % of its variance. Thus, in the present cross-sectional study, resting EE was the most important determinant of fat mass.

Analysis of Variance↗

Quantification of the expression level of the gene encoding the catalytic subunit of telomerase in testicular tissue specimens predicts successful sperm recovery.

BACKGROUND: The objective of the present study was to evaluate the quantitative detection of human telomerase reverse transcriptase (hTERT) mRNA as a new molecular diagnostic parameter in the work-up of testicular tissue specimens from patients presenting with non-obstructive azoospermia. M ETHODS: hTERT mRNA expression was quantified in 49 cryopreserved testicular tissue specimens by fluorescence real-time RT-PCR in a LightCycler. This was paralleled by conventional histological work-up in all tissue specimens and additional semithin sectioning preparation in cases with maturation arrest (n = 20) and Sertoli cell-only syndrome (SCOS; n = 12). RESULTS: The average normalized hTERT expression (N(hTERT)) was 136.1 +/- 41.7 copies (mean +/- standard deviation) in tissue specimens with presence of haploid germs cells, N(hTERT) = 48.2 +/- 21.0 copies in those with maturation arrest and N(hTERT) = 2.7 +/- 2.8 copies in those with SCOS. The discriminant analysis showed that detection of N(hTERT) was able correctly to classify 89.0% of the investigated tissue specimens. CONCLUSIONS: Our results demonstrate that quantitative detection of hTERT mRNA expression in testicular tissue enables a molecular-diagnostic subclassification of spermatogenesis disorders. Quantitative detection of hTERT in testicular biopsies is thus well suited for predicting successful sperm recovery in patients with azoospermia and is a useful molecular diagnostic parameter for supplementing the histopathological evaluation.

Adult↗