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Jens Dreier

Bio: Jens Dreier is an academic researcher from Ruhr University Bochum. The author has contributed to research in topics: Vitamin D and neurology & Streptococcus gallolyticus. The author has an hindex of 35, co-authored 114 publications receiving 3472 citations. Previous affiliations of Jens Dreier include Bielefeld University & University of Münster.


Papers
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Journal ArticleDOI
TL;DR: It is suggested that vitamin D supplementation might increase testosterone levels in healthy overweight men undergoing a weight reduction program who participated in a randomized controlled trial.
Abstract: The male reproductive tract has been identified as a target tissue for vitamin D, and previous data suggest an association of 25-hydroxyvitamin D [25(OH)D] with testosterone levels in men. We therefore aimed to evaluate whether vitamin D supplementation influences testosterone levels in men. Healthy overweight men undergoing a weight reduction program who participated in a randomized controlled trial were analyzed for testosterone levels. The entire study included 200 nondiabetic subjects, of whom 165 participants (54 men) completed the trial. Participants received either 83 μg (3,332 IU) vitamin D daily for 1 year (n = 31) or placebo (n =2 3). Initial 25(OH)D concentrations were in the deficiency range (< 50 nmol/l) and testosterone values were at the lower end of the reference range (9.09-55.28 nmol/l for males aged 20-49 years) in both groups. Mean circulating 25(OH)D concentrations increased significantly by 53.5 nmol/l in the vitamin D group, but remained almost constant in the placebo group. Compared to baseline values, a significant increase in total testosterone levels (from 10.7 ± 3.9 nmol/l to 13.4 ± 4.7 nmol/l; p < 0.001), bioactive testosterone (from 5.21 ± 1.87 nmol/l to 6.25 ± 2.01 nmol/l; p = 0.001), and free testosterone levels (from 0.222 ± 0.080 nmol/l to 0.267 ± 0.087 nmol/l; p = 0.001) were observed in the vitamin D supplemented group. By contrast, there was no significant change in any testosterone measure in the placebo group. Our results suggest that vitamin D supplementation might increase testosterone levels. Further randomized controlled trials are warranted to confirm this hypothesis.

258 citations

Journal Article
TL;DR: It is shown for the first time that CD163 is significantly up-regulated by glucocorticoids, suggesting that it might play an important role in inflammatory processes.
Abstract: The RM3/1 Ag is a membrane glycoprotein restricted to human monocytes and macrophages that evolve in the late phase of inflammation. Peptide sequence analysis of the RM3/1 protein revealed similarity to CD163, a member of the scavenger receptor cysteine-rich family. Using specific Abs (RM3/1, Ki-M8), we demonstrate an identical cellular regulation for the RM3/1 and the CD163 protein. Most notably, we show for the first time that CD163 is significantly up-regulated by glucocorticoids. In contrast, the protein is down-regulated by the immunosuppressant cyclosporin A and by phorbol esters, while the inflammatory mediator LPS has no significant influence on the expression. We describe the first isolation of a full-length cDNA of CD163 and expression of the corresponding protein. Several splice variants of CD163 exist, and we elucidated the kinetics of induction of three major mRNA splice variants by fluticasone propionate; another splice variant was proved to be unresponsive to this glucocorticoid. Taken together with a previous result showing an involvement of RM3/1 in adhesion of monocytes to the activated endothelium, we discuss that CD163 might play an important role in inflammatory processes.

243 citations

Journal ArticleDOI
TL;DR: Various real-time RT-PCRs utilizing the coliphage MS2 replicase gene, which differ in detection format, amplicon size, and efficiency of amplification are designed, which demonstrate low variability and can be applied in various RT- PCR assays.
Abstract: Diagnostic systems based on reverse transcription (RT)-PCR are widely used for the detection of viral genomes in different human specimens. The application of internal controls (IC) to monitor each step of nucleic acid amplification is necessary to prevent false-negative results due to inhibition or human error. In this study, we designed various real-time RT-PCRs utilizing the coliphage MS2 replicase gene, which differ in detection format, amplicon size, and efficiency of amplification. These noncompetitive IC assays, using TaqMan, hybridization probe, or duplex scorpion probe techniques, were tested on the LightCycler and Rotorgene systems. In our approach, clinical specimens were spiked with the control virus to monitor the efficiency of extraction, reverse transcription, and amplification steps. The MS2 RT-PCR assays were applied for internal control when using a second target hepatitis C virus RNA in duplex PCR in blood donor screening. The 95% detection limit was calculated by probit analysis to 44.9 copies per PCR (range, 38.4 to 73.4). As demonstrated routinely, application of MS2 IC assays exhibits low variability and can be applied in various RT-PCR assays. MS2 phage lysates were obtained under standard laboratory conditions. The quantification of phage and template RNA was performed by plating assays to determine PFU or via real-time RT-PCR. High stability of the MS2 phage preparations stored at −20°C, 4°C, and room temperature was demonstrated.

215 citations

Journal ArticleDOI
TL;DR: The NAT method provides a sensitive possibility for HEV testing in connection with raising concerns regarding blood safety, and is compared with different nucleic acid amplification technique (NAT) methods for the detection of HEV in blood components.
Abstract: The risk of transfusion-transmitted hepatitis E virus (HEV) infections by contaminated blood products remains unknown. In the present study, we evaluated and compared different nucleic acid amplification technique (NAT) methods for the detection of HEV in blood components. Minipools of a total of 16,125 individual blood donors were screened for the presence of HEV RNA using the highly sensitive RealStar HEV RT-PCR kit, revealing a minimum detection limit of 4.66 IU/ml. Thirteen donors were HEV RNA positive (0.08%), and of these donors, only three already showed reactive IgM antibody titers. The detected HEV strains all belonged to genotype 3 and were most closely related to German HEV strains from wild boars and pigs as well as from human hepatitis E cases. Furthermore, HEV RNA and HEV-specific IgM and IgG titers were determined in 136 blood donors with elevated alanine aminotransferase (ALT) levels and in 200 donors without pathological findings. HEV RNA was not detectable, but 8.08% (elevated ALT) and 0.5% (nonelevated ALT) of donors showed reactive HEV IgM titers. The overall seroprevalence rate of HEV IgG amounted to 5.94% (elevated ALT, 5.88%; nonelevated ALT, 6.0%). The clinical relevance of transfusion-associated hepatitis E infection still requires further investigation. However, in connection with raising concerns regarding blood safety, our NAT method provides a sensitive possibility for HEV testing.

147 citations

Journal ArticleDOI
TL;DR: A daily vitamin D dose of 4000 IU did not reduce mortality in patients with advanced HF but was associated with a greater need for MCS implants, which indicates caution regarding long-term supplementation with moderately high vitamin D doses.
Abstract: Aims Circulating 25-hydroxyvitamin D (25OHD) levels <75 nmol/L are associated with a nonlinear increase in mortality risk. Such 25OHD levels are common in heart failure (HF). We therefore examined whether oral vitamin D supplementation reduces mortality in patients with advanced HF. Methods and results Four hundred HF patients with 25OHD levels <75 nmol/L were randomized to receive 4000 IU vitamin D daily or matching placebo for 3 years. Primary endpoint was all-cause mortality. Key secondary outcome measures included hospitalization, resuscitation, mechanical circulatory support (MCS) implant, high urgent listing for heart transplantation, heart transplantation, and hypercalcaemia. Initial 25OHD levels were on average <40 nmol/L, remained around 40 nmol/L in patients assigned to placebo and plateaued around 100 nmol/L in patients assigned to vitamin D. Mortality was not different in patients receiving vitamin D (19.6%; n = 39) or placebo (17.9%; n = 36) with a hazard ratio (HR) of 1.09 [95% confidence interval (CI): 0.69-1.71; P = 0.726]. The need for MCS implant was however greater in patients assigned to vitamin D (15.4%, n = 28) vs. placebo [9.0%, n = 15; HR: 1.96 (95% CI: 1.04-3.66); P = 0.031]. Other secondary clinical endpoints were similar between groups. The incidence of hypercalcaemia was 6.2% (n = 10) and 3.1% (n = 5) in patients receiving vitamin D or placebo (P = 0.192). Conclusion A daily vitamin D dose of 4000 IU did not reduce mortality in patients with advanced HF but was associated with a greater need for MCS implants. Data indicate caution regarding long-term supplementation with moderately high vitamin D doses. Trial Registration Information clinicaltrials.gov Idenitfier: NCT01326650.

131 citations


Cited by
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Journal ArticleDOI
21 Jul 1979-BMJ
TL;DR: It is suggested that if assessment of overdoses were left to house doctors there would be an increase in admissions to psychiatric units, outpatients, and referrals to social services, but for house doctors to assess overdoses would provide no economy for the psychiatric or social services.
Abstract: admission. This proportion could already be greater in some parts of the country and may increase if referrals of cases of self-poisoning increase faster than the facilities for their assessment and management. The provision of social work and psychiatric expertise in casualty departments may be one means of preventing unnecessary medical admissions without risk to the patients. Dr Blake's and Dr Bramble's figures do not demonstrate, however, that any advantage would attach to medical teams taking over assessment from psychiatrists except that, by implication, assessments would be completed sooner by staff working on the ward full time. What the figures actually suggest is that if assessment of overdoses were left to house doctors there would be an increase in admissions to psychiatric units (by 19°U), outpatients (by 5O°'), and referrals to social services (by 140o). So for house doctors to assess overdoses would provide no economy for the psychiatric or social services. The study does not tell us what the consequences would have been for the six patients who the psychiatrists would have admitted but to whom the house doctors would have offered outpatient appointments. E J SALTER

4,497 citations

Journal ArticleDOI
TL;DR: The American Heart Association, in conjunction with the National Institutes of Health, annually reports the most up-to-date statistics related to heart disease, stroke, and cardiovascul...
Abstract: Background: The American Heart Association, in conjunction with the National Institutes of Health, annually reports the most up-to-date statistics related to heart disease, stroke, and cardiovascul...

3,034 citations

Journal ArticleDOI
TL;DR: In conclusion, injured skeletal muscle recruits monocyte (MO) exhibiting inflammatory profiles that operate phagocytosis and rapidly convert to antiinflammatory MPs that stimulate myogenesis and fiber growth.
Abstract: Macrophages (MPs) are important for skeletal muscle regeneration in vivo and may exert beneficial effects on myogenic cell growth through mitogenic and antiapoptotic activities in vitro. However, MPs are highly versatile and may exert various, and even opposite, functions depending on their activation state. We studied monocyte (MO)/MP phenotypes and functions during skeletal muscle repair. Selective labeling of circulating MOs by latex beads in CX3CR1GFP/+ mice showed that injured muscle recruited only CX3CR1lo/Ly-6C+ MOs from blood that exhibited a nondividing, F4/80lo, proinflammatory profile. Then, within muscle, these cells switched their phenotype to become proliferating antiinflammatory CX3CR1hi/Ly-6C− cells that further differentiated into F4/80hi MPs. In vitro, phagocytosis of muscle cell debris induced a switch of proinflammatory MPs toward an antiinflammatory phenotype releasing transforming growth factor β1. In co-cultures, inflammatory MPs stimulated myogenic cell proliferation, whereas antiinflammatory MPs exhibited differentiating activity, assessed by both myogenin expression and fusion into myotubes. Finally, depletion of circulating MOs in CD11b–diphtheria toxin receptor mice at the time of injury totally prevented muscle regeneration, whereas depletion of intramuscular F4/80hi MPs at later stages reduced the diameter of regenerating fibers. In conclusion, injured skeletal muscle recruits MOs exhibiting inflammatory profiles that operate phagocytosis and rapidly convert to antiinflammatory MPs that stimulate myogenesis and fiber growth.

1,664 citations

Journal ArticleDOI
11 Jan 2001-Nature
TL;DR: The identification of the acute phase-regulated and signal-inducing macrophage protein, CD163, as a receptor that scavenges haemoglobin by mediating endocytosis of haptoglobin–haemoglobin complexes is reported.
Abstract: Intravascular haemolysis is a physiological phenomenon as well as a severe pathological complication when accelerated in various autoimmune, infectious (such as malaria) and inherited (such as sickle cell disease) disorders1. Haemoglobin released into plasma is captured by the acute phase protein haptoglobin, which is depleted from plasma during elevated haemolysis1. Here we report the identification of the acute phase-regulated and signal-inducing macrophage protein, CD163, as a receptor that scavenges haemoglobin by mediating endocytosis of haptoglobin–haemoglobin complexes. CD163 binds only haptoglobin and haemoglobin in complex, which indicates the exposure of a receptor-binding neoepitope. The receptor–ligand interaction is Ca2+-dependent and of high affinity. Complexes of haemoglobin and multimeric haptoglobin (the 2-2 phenotype) exhibit higher functional affinity for CD163 than do complexes of haemoglobin and dimeric haptoglobin (the 1-1 phenotype). Specific CD163-mediated endocytosis of haptoglobin–haemoglobin complexes is measurable in cells transfected with CD163 complementary DNA and in CD163-expressing myelo-monocytic lymphoma cells.

1,536 citations

Journal ArticleDOI
TL;DR: The American Heart Association, through its Statistics Committee, continuously monitors and evaluates sources of data on heart disease and stroke in the United States to provide the most current information available in the annual Statistical Update as discussed by the authors .
Abstract: The American Heart Association, in conjunction with the National Institutes of Health, annually reports the most up-to-date statistics related to heart disease, stroke, and cardiovascular risk factors, including core health behaviors (smoking, physical activity, diet, and weight) and health factors (cholesterol, blood pressure, and glucose control) that contribute to cardiovascular health. The Statistical Update presents the latest data on a range of major clinical heart and circulatory disease conditions (including stroke, congenital heart disease, rhythm disorders, subclinical atherosclerosis, coronary heart disease, heart failure, valvular disease, venous disease, and peripheral artery disease) and the associated outcomes (including quality of care, procedures, and economic costs).The American Heart Association, through its Statistics Committee, continuously monitors and evaluates sources of data on heart disease and stroke in the United States to provide the most current information available in the annual Statistical Update. The 2022 Statistical Update is the product of a full year's worth of effort by dedicated volunteer clinicians and scientists, committed government professionals, and American Heart Association staff members. This year's edition includes data on the monitoring and benefits of cardiovascular health in the population and an enhanced focus on social determinants of health, adverse pregnancy outcomes, vascular contributions to brain health, and the global burden of cardiovascular disease and healthy life expectancy.Each of the chapters in the Statistical Update focuses on a different topic related to heart disease and stroke statistics.The Statistical Update represents a critical resource for the lay public, policymakers, media professionals, clinicians, health care administrators, researchers, health advocates, and others seeking the best available data on these factors and conditions.

1,483 citations