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W Vogel

Publications and source records attributed to W Vogel.

At least 19 recordsLinked to original sources
PubMed2007

A comparison of the variability spectra of two genomic loci in a European group of individuals reveals fundamental differences pointing to selection or a population bottleneck.

Knowledge about the variability spectra of neutrally evolving sequences in a population is a prerequisite for the identification of genes, which may have been under positive selection during recent human evolution. Here, we report the results of a re-sequencing project of a presumably neutrally evolving chromosome 22 locus with a severely reduced recombination frequency in a group of 24 individuals of German origin. The comparison of these data with the results of a similar analysis of a chromosome 17 locus revealed striking differences, although the same group of individuals was used. For the chromosome 17 locus two well-separated groups of sequences, a positive value of Tajima's D and a TMRCA of 700,000 years were observed. In contrast, the sequences from the chromosome 22 locus were found to be relatively homogeneous, with no deep splits between subgroups; the obtained value for Tajima's D was negative and the TMRCA was only 260,000 years. These discrepancies may be explained by selection or demographic processes. Regarding demography, the most plausible explanation is the assumption of a severe bottleneck in the history of the European population: in the case of the chromosome 17 locus two ancient lineages passed this bottleneck; for the chromosome 22 locus it was only one ancient lineage.

Chromosomes, Human, Pair 17↗
PubMed2006

Unusual distribution of red marrow mimicking chloroma in a patient with acute myelogenous leukemia.

We present a case of unusual distribution of red marrow in a patient with extramedullary acute myelogenous leukemia (AML). In adults, hematopoietic marrow is usually located in the axial skeleton and the proximal aspects of the limbs, except for the epiphyses. Nodular islets of red marrow located in the epiphyseal and distal parts of the limbs may mimic tumoral infiltration and be mistaken for chloroma in a patient with AML.

Aged↗
PubMed2006

Universal measurement of quantum correlations of radiation.

A measurement technique is proposed which, in principle, allows one to observe the general space-time correlation properties of a quantized radiation field. Our method, called balanced homodyne correlation measurement, unifies the advantages of balanced homodyne detection with those of homodyne correlation measurements.

Journal Article↗
PubMed2006

[Prospective evaluation of prostate cancer screening in men with a family history of the disease].

BACKGROUND: Family history is one of the strongest risk factors for prostate cancer. In this prospective study we evaluated the results of prostate cancer screening performed in healthy brothers of prostate cancer patients. The detection rate of prostate cancer and the positive predictive value of the examinations were determined. MATERIAL AND METHODS: The study population comprised 513 healthy men who were 38-75 years of age (median 62.0 years). Of these men, 268 having only one affected brother with prostate cancer were assigned to the sporadic group, and 245 probands having 2-10 affected relatives were assigned to the familial group. An abnormal PSA and/or a pathological digital rectal examination (DRE) was noted in 17.5% of familial (43/245) and 15.8% of sporadic probands (35/268). A biopsy of the prostate was performed in 60.5% of familial (26/43) and 71.4% of sporadic (25/35) men with pathological findings. RESULTS: Prostate cancer was found in 15 of 26 familial (57.7%) and 16 of 25 sporadic (64.0%) probands by prostate biopsy. The overall detection rate was 6.0% (31/513). CONCLUSION: Due to an increased prevalence the detection rate of prostate cancer and the positive predictive value of PSA and/or DRE are higher in men with a family history as expected in an unselected population. Our data suggest that in predisposed men prostate cancer screening should be recommended early. Furthermore an early indication for prostate biopsy is necessary. This recommendation should also be applied if only one first-degree relative has prostate cancer.

Adult↗
PubMed2006

Determination of residual T- and B-cell content after immunomagnetic depletion: proposal for flow cytometric analysis and results from 103 separations.

BACKGROUND: T- and B-cell depletion of apheresis products is an attractive alternative to standard stem cell enrichment in haplo-identical transplantation. Thorough T- and B-cell depletion is necessary for prevention of acute GvHD and T-cell depletion-associated lymphoproliferative disorders. However, the large number of non-T and -B cells in the graft requires special protocols for the determination of extremely low frequencies of residual T cells. METHODS: Apheresis products from healthy donors were T- and B-cell depleted by the CliniMACS system using CD3 and CD19 Ab reagents and the LS tubing set. The recovery of cells and degree of depletion were determined. A four-color multigating strategy was used for enumeration of residual T and B cells. RESULTS: One-hundred and three separations were performed, with a mean cell recovery of 38+/-12%, CD34 recovery of 61+/-16% and CD56 recovery of 63+/-33%. T and B cells were depleted by log 4.15+/-0.46 and log 3.64+/-0.63, respectively. Four-color multigating flow cytometry allowed the detection of single T cells. DISCUSSION: Combined T- and B-cell depletion is a feasible method for obtaining stem cell grafts with acceptable stem cell recovery, profound T- and B-cell depletion and a very high amount of NK cells and monocytes. However, analysis of residual T cells is challenging and requires special protocols.

Acute Disease↗
PubMed2006

Safety and efficacy of lamivudine in patients with severe acute or fulminant hepatitis B, a multicenter experience.

Acute hepatitis B progresses to liver failure with the need of liver transplantation in about 1% of cases. We treated patients with severe acute or fulminant hepatitis B with lamivudine in an attempt to prevent hepatitis B virus (HBV) reinfection after potential liver transplantation. Since September 2000, 17 patients with severe acute or fulminant HBV infection were treated with 100 or 150 mg lamivudine daily once we had evidence for a severe course as indicated by an INR >2.0. These were compared to a historic control from our unit and to external patients. Fourteen of the 17 patients (82.4%) survived with full recovery without liver transplantation. All these 14 individuals cleared HBsAg on lamivudine within less than 6 months. Twelve patients recovered quickly as indicated by a normalized prothrombin time within 1 week while two patients had a more prolonged course. None of the patients showed an adverse event. Three patients requiring transplantation despite lamivudine therapy had more advanced disease on admission, of whom one had additionally ingested paracetamol (acetaminophen) while the second was already HBV-DNA negative by polymerase chain reaction on admission. The lamivudine treated patients had significant higher frequency of survival without liver transplantation 82.4 vs 20% (4/20) in the historic control (P < 0.001). Similar data were derived from external centres using lamivudine (15/20, 75%). Lamivudine is safe in patients with severe acute or fulminant hepatitis B, leading to fast recovery with the potential to prevent liver failure and liver transplantation when administered early enough.

Adult↗
PubMed2005

Inseparability criteria for continuous bipartite quantum states.

We provide necessary and sufficient conditions for the partial transposition of bipartite harmonic quantum states to be nonnegative. The conditions are formulated as an infinite series of inequalities for the moments of the state under study. The violation of any inequality of this series is a sufficient condition for entanglement. Previously known entanglement conditions are shown to be special cases of our approach.

Journal Article↗
PubMed2005

Effect of pH on photoluminescence enhancement in Pb-doped ZnS nanoparticles.

Narrowly dispersed Pb-doped zinc sulfide nanoparticles were synthesized at room temperature using a chemical method in which the nanoparticle surfaces were passivated using mercaptoethanol. The maximum intensity of the broad green luminescence (approximately 530 nm) from these nanoparticles was observed at an optimum dopant concentration of 0.104 Pb wt%. The emission intensity was found to depend on the synthesis pH conditions, thus yielding maximum intensity at 5.0 pH. Comparatively lower emission intensities were observed for the other pH values (2.5-9.0 pH range). This may be due to the pH-dependent Cl- (as well as Na+) incorporation into the ZnS matrix, which possibly helps in inducing required density of impurity (donor/co-activator) states in the energy gap of ZnS nanoparticles. X-ray diffraction analysis using Debye functional analysis showed that the particle size is 2.8+/-0.3 nm.

Journal Article↗
PubMed2005

Mutation screening and association study of RNASEL as a prostate cancer susceptibility gene.

To date, germline mutations have been found in three candidate genes for hereditary prostate cancer: ELAC2 at 17p11, RNASEL at 1q25 and MSR1 at 8p22. RNASEL, encoding the 2',5'-oligoadenylate-dependant RNase L, seems to have rare mutations in different ethnicities, such as M1I in Afro-Americans, E265X in men of European descent and 471delAAAG in Ashkenazi Jews. In order to evaluate the relevance of RNASEL in the German population, we sequenced its open reading frame to determine the spectrum and frequency of germline mutations. The screen included 303 affected men from 136 Caucasian families, of which 45 met the criteria for hereditary prostate cancer. Variants were analysed using a family-based association test, and genotyped in an additional 227 sporadic prostate cancer patients and 207 controls. We identified only two sib pairs (1.4% of our families) cosegregating conspicuous RNASEL variants with prostate cancer: the nonsense mutation E265X, and a new amino-acid substitution (R400P) of unknown functional relevance. Both alleles were also found at low frequencies (1.4 and 0.5%, respectively) in controls. No significant association of polymorphisms (I97L, R462Q and D541E) was observed, neither in case-control analyses nor by family-based association tests. In contrast to previous reports, our study does not suggest that common variants (i.e. R462Q) modify disease risk. Our results are not consistent with a high penetrance of deleterious RNASEL mutations. Due to the low frequency of germline mutations present in our sample, RNASEL does not have a significant impact on prostate cancer susceptibility in the German population.

Aged↗
PubMed2005

[Is the prostate cancer screening behaviour of men with familial predisposition predictable?].

Little is known about the motives of German men to attend or refuse preventive checkups for prostate cancer. The aims of this study were to investigate if in men with familial predisposition screening behaviours are influenced by epidemiological or clinical parameters of prostate cancer of their affected relatives. 476 probands with one and 312 probands with at least two affected relatives were advised in writing to have a PSA-test and DRE done at their local urologists. We evaluated if the response rate was correlated to the proband's age, to the number and the age of onset of their affected relatives and also to the clinical course of their disease. Our data implicate that in men with familial predisposition the acceptance of prostate cancer screening is influenced only by individual characteristics and personal attitude and not by factors within the family. To which extent the awareness of disease risk is modified by familial predisposition remains to be evaluated.

Adult↗
PubMed2005

[Ethical considerations in 2005 on geriatric patients' end of life].

Geriatric medicine is challenged by new ethical questions with regard to demographic changes and medical progress. Aged patients deserve the full range of modern medical care, but they also have the right to die in dignity when their time has come. The decision whether a therapeutically active or passive approach should be preferred depends on the disease with its symptoms, functional deficiencies, and prognosis, and especially on the patient's will which has to be evaluated thoroughly, eventually with the help of his family. In any doubt, life deserves preference, but in cases with a bad prognosis medical interventions like intensive care, tube feeding, resuscitation, etc. may be excluded in order to maintain life quality (e. g. through pain control), avoid suffering, and allow peaceful dying. Despite the geriatrician's personal responsibility for all medical measures, his decisions should be explained and accepted by the geriatric team and the patient's family. Patient's welfare clearly needs to be preferred to disease management or economic considerations.

Attitude to Death↗
PubMed2005

Infectious complications limit the outcome of liver transplantation in medical urgency code 2 patients.

The Organ shortage has caused an accumulation of acutely decompensated patients listed as medical urgency code 2 (MUC 2) (United network for Organ Sharing 2) while awaiting liver transplantation. Between June 1997 and June 2003, 22 of 360 liver transplantation patients (6%) were listed as MUC 2. Prophylactic immunosuppression consisted of calcineurin inhibitor-based drug therapy, using antithymocyte globulin or interleukin-2 receptor antagonist induction in 64%. The overall perioperative infection rate was 50%, and the rejection rate was 23%. We observed 7 episodes of oral or genital herpes simplex virus lesions; 2 patients (both with cytomegalovirus-mismatched transplants) developed cytomegalovirus disease, and another 5 patients received ganciclovir for preemptive therapy or prophylaxis. Two patients developed pneumonia: 5, sepsis that originated in 4 cases from a contaminated central venous line; and 1 methicillin-resistant endocarditis, which resulted in Staphylococcus aureus lethal outcome. After a median follow up of 3 years, 1 patient underwent a repeat transplantation procedure and 6 patients had died, 4 of them from infectious complications. Liver transplantation of MUC 2-listed patients may result in acceptable results similar to those of MUC 3 and MUC 4 categories.

Adult↗
PubMed2005

Circulating adiponectin reflects severity of liver disease but not insulin sensitivity in liver cirrhosis.

BACKGROUND: The adipocytokine adiponectin has been proposed to play important roles in the regulation of energy homeostasis, insulin sensitivity and shows anti-inflammatory properties. AIM: In this study we investigated the role of circulating adiponectin in different chronic liver diseases, its regulation by systemic anti-tumour necrosis factor (TNF)-alpha treatment and its hepatic metabolism. PATIENTS AND METHODS: Plasma adiponectin levels were determined in 87 patients with liver cirrhosis of different aetiologies, seven patients with alcoholic steatohepatitis undergoing systemic anti-TNF-alpha treatment, in 11 patients with liver cirrhosis receiving transjugular intrahepatic portosystemic shunt implantation and in 21 healthy controls. RESULTS: Adiponectin levels were significantly higher in all subjects with liver cirrhosis of different aetiologies when compared with healthy controls and increased dependent on Child-Pugh classification. In subjects with alcoholic steatohepatitis, systemic anti-TNF-alpha treatment caused a significant decrease in circulating adiponectin. Adiponectin concentrations were similar in portal, hepatic and peripheral veins. No correlation between adiponectin levels and insulin resistance was found in any patient group. CONCLUSIONS: Our data suggest that circulating adiponectin is increased in liver cirrhosis independent of the aetiology of liver disease. We suggest that high adiponectin levels in chronic liver disease might reflect one of the body's anti-inflammatory mechanisms in chronic liver diseases.

Adiponectin↗
PubMed2005

Radiosensitivity detected by the micronucleus test is not generally increased in sporadic prostate cancer patients.

The micronucleus test (MNT) has shown increased micronuclei (MN) frequencies in BRCA associated and sporadic breast cancer patients, Ataxia telangiectasia and Nijmegen Breakage Syndrome patients, demonstrating a common cellular phenotype of increased radiosensitivity. Some genes, causative of these diseases, have also recently been associated with prostate cancer. In order to investigate if prostate cancer exhibits the cellular phenotype of increased radiosensitivity, we performed MNT analysis on 22 sporadic prostate cancer patients and 43 male controls. We determined the baseline MN frequency, in order to see in vivo chromosomal damage without radiation, and induced (after irradiation with 2 Gy) frequency of MN, both in binucleated cells (BNC) obtained from cultured peripheral blood lymphocytes. An automated image analysis system was used to score the MN employing two different classifiers (Classifier A and B) for detection of BNC. The mean baseline frequencies were 48/43 MN/1000 BNC (A/B) for the controls and 42/50 (A/B) for prostate cancer patients. The induced MN frequencies amounted to 107/111 MN/1000 BNC (A/B) for controls and 111/114 MN/1000 BNC (A/B) for prostate cancer patients. The obtained MN frequencies did not result in a statistically significant difference between unselected cases and controls. However, restricting the analysis to young patients (50-60 years, N = 7) and age-matched controls (N = 7) revealed marginally significant higher MN frequencies in patients. We conclude that increased radiosensitivity is not a property of prostate cancer patients in general.

Aged↗
PubMed2004

Accuracy of rigid CT-FDG-PET image registration of the liver.

Diagnostic and surgical strategies could benefit from accurate localization of liver malignancies via CT-FDG-PET image registration. However, registration uncertainty occurs due to protocol differences in data-acquisition, the limited spatial resolution of positron emission tomography (PET) and the low uptake of 18F-fluorodeoxyglucose (FDG) in normal liver tissue. To assess this uncertainty, methods were presented to estimate registration precision and systematic bias. A semi-automatic, organ-focused method was investigated to minimize the uncertainty well beyond the typical uncertainty of 5-10 mm obtained by commonly available methods. By restricting registration to the liver region and by isolating the liver on computed tomography (CT) from surrounding structures using a thresholding technique, registration was achieved using the mutual information-based method as implemented in insight toolkit (ITK). CT and FDG-PET images of 10 patients with liver metastases were registered rigidly a number of times. Results of the organ-focused method were compared to results of three commonly available methods (a manual, a landmark-based and a 'standard' mutual information-based method) where no dedicated image processing was performed. The proposed method outperformed the other methods with a precision (mean+/-s.d.) of 2.5+/-1.3 mm and a bias of 1.9 mm with a 95% CI of [1.0, 2.8] mm. Unlike the commonly available methods, our approach allows for robust CT-FDG-PET registration of the liver, with an accuracy better than the spatial resolution of the PET scanner that was used.

Fluorodeoxyglucose F18↗
PubMed2004

Divergent genetic and epigenetic post-zygotic isolation mechanisms in Mus and Peromyscus.

Interspecific hybridization in the rodent genera Peromyscus and Mus results in abnormal placentation. In the Peromyscus interspecies hybrids, abnormal allelic interaction between an X-linked locus and the imprinted paternally expressed Peg3 locus was shown to cause the placental defects. In addition, loss-of-imprinting (LOI) of Peg3 was positively correlated with increased placental size. As in extreme cases this placental dysplasia constitutes a post-zygotic barrier against interspecies hybridization, this finding was the first direct proof that imprinted genes may be important in speciation and thus in evolution. In the Mus interspecies hybrids, a strong role of an X-linked locus in placental dysplasia has also been detected. However, here we show by backcross and allele specific expression analyses that neither LOI of Peg3 nor abnormal interactions between Peg3 and an X-linked locus are involved in generating placental dysplasia in Mus hybrids, although the placental phenotypes observed in the two genera seem to be identical. In contrast to this, another dysgenesis effect common to Peromyscus and Mus hybrids, altered foetal growth, is caused at least in part by the same X-chromosomal regions in both genera. These findings first underline the strong involvement of the X-chromosome in the genetics of speciation. Secondly, they indicate that disruption of epigenetic states, such as LOI, at specific loci may be involved in hybrid dysgenesis effects in one group, but not in another. Thus, we conclude that even in closely related groups divergent molecular mechanisms may be involved in the production of phenotypically similar post-zygotic barriers against hybridization.

Alleles↗
PubMed2004

Rituximab consolidation after high-dose chemotherapy and autologous blood stem cell transplantation in follicular and mantle cell lymphoma: a prospective, multicenter phase II study.

BACKGROUND: Patients with follicular (FL) or mantle cell lymphoma (MCL) are incurable with conventional therapy. We investigated the safety and efficacy of rituximab consolidation after autologous stem cell transplantation (ASCT) in order to prevent relapse by clearance of minimal residual disease (MRD). METHODS: Rituximab was given approximately 8 weeks after CD34+ cell enriched ASCT at 375 mg/m2, weekly for 4 weeks. Monitoring of MRD was performed by repetitive PCR analyses. RESULTS: Thirty-one patients were included; one died early after ASCT before rituximab administration. Thirty patients (20 FL, 10 MCL) were evaluable after rituximab consolidation, and 27 of these were assessable for MRD detection. Rituximab consolidation post-ASCT was safe, the most common toxicity being infection. At a median follow-up of 42 months (range 13-96) after ASCT, 25 patients were censored with an actuarial event-free survival (EFS) of 81% at 4 and 5 years. Four patients (two FL, two MCL) relapsed, and one additional MCL patient died unexpectedly in complete remission. PCR-negativity was observed in 22% of the patients before ASCT, 53% post-ASCT (P=0.0547), 72% after rituximab (P=0.0018) and 100% at 6 months post-transplant (P < 0.001). CONCLUSIONS: One single course of rituximab consolidation given after ASCT is safe, may help to eliminate MRD and may translate into improved EFS in both FL and MCL patients.

Adult↗