Concordance and Discordance of Sexual Identity, Sexual Experience, and Current Sexual Behavior in 45-Year-Old Men: Results From the German Male Sex-Study.

INTRODUCTION: Discordance of various aspects of sexual orientation has been mostly studied in young adults or in small samples of heterosexual men. Studies focusing on concordance and discordance of aspects of sexual orientation in representative samples of middle-aged men including homosexual men are scarce. AIM: To investigate concordant and discordant sexual behavior in 45-year-old German men with a special focus on homosexual identified men. METHODS: Data for this cross-sectional study were collected within the German Male Sex-Study. Participants were 45-year-old Caucasian males from the general population. Men self-reported on sexual identity, sexual experience, and current sexual behavior. Associations between sexual identity, experience, and behavior were analyzed using the chi-square test. MAIN OUTCOME MEASURE: Associations of sexual identity with sexual experience and behavior in a community-based sample of men, and discordance of sexual identity and behavior especially in the subgroup of homosexual men. RESULTS: 12,354 men were included in the study. 95.1% (n = 11.749) self-identified as heterosexual, 3.8% (n = 471) as homosexual, and 1.1% (n = 134) as bisexual. Sexual identity was significantly associated with sexual experience and behavior. 85.5% of all men had recently been sexually active, but prevalence of sexual practices varied. In hetero- and bisexuals, vaginal intercourse was the most common sexual practice, whereas oral sex was the most common in homosexuals. A discordance of sexual identity was especially found in homosexual men: 5.5% of homosexuals only had sexual experiences with women, and 10.3% of homosexuals recently had vaginal intercourse. In this latter subgroup, only one-quarter ever had sexual experience with a man, and three-quarters had only engaged in sexual activity with a woman. CONCLUSION: Sexual identity is associated with differences in sexual experience and behavior in German middle-aged men. A considerable proportion of homosexual identified men live a heterosexual life. Goethe VE, Angerer H, Dinkel A, et al. Concordance and Discordance of Sexual Identity, Sexual Experience, and Current Sexual Behavior in 45-Year-Old-Men: Results From the German Male Sex-Study. Sex Med 201;6:282-290.

Chondrocyte cultures from human proximal interphalangeal finger joints.

Osteoarthritis (OA) of the hand is a common disease resulting in pain and impaired function. The pathogenesis of hand OA (HOA) is elusive and models to study it have not been described. Chondrocyte culture has been essential to understand cartilage degeneration, which is a hallmark of OA. We investigated the feasibility of human chondrocyte culture derived from proximal interphalangeal (PIP) finger joints. Hyaline cartilage of the PIP and knee joints was obtained from human cadavers. Chondrocytes harvested up to 236 h after death of the donors were viable and expressed chondrocyte-specific genes. Gene expression comparing chondrocytes from PIP and knee joints using Affymetrix GeneChip arrays resulted in a unique PIP-specific gene expression pattern. Genes involved in developmental processes including the WNT pathway were differentially expressed between the joints. These findings suggest that our knowledge on chondrocyte biology derived mainly from knee and hip joints may not apply to chondrocytes of the PIP joints and some of the distinctive features of HOA may be caused by the specific properties of PIP chondrocytes. Chondrocyte culture of PIP cartilage is a novel tool to study cartilage degeneration in HOA. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:1569-1575, 2016.

Epigenetic differences in human cartilage between mild and severe OA.

The development of osteoarthritis (OA) depends on genetic and environmental factors, which influence the biology of the chondrocyte via epigenetic regulation. Changes within the epigenome might lead the way to discovery of new pathogenetic pathways. We performed a genome-wide methylation screening to identify potential differences between paired mild and severe osteoarthritic human cartilage. Sixteen female patients suffering from OA underwent total knee joint replacement. Cartilage specimens collected from corresponding macroscopically undamaged and from damaged areas were processed for DNA extraction and histology to evaluate the histological grading of the disease. Paired specimens were analysed for the methylation status of the whole genome using human promoter microarrays (Agilent, Santa Clara, CA). Selected target genes were then validated via methylation-specific qPCR. One thousand two hundred and fourteen genetic targets were identified differentially methylated between mild and severe OA. One thousand and seventy of these targets were found hypermethylated and 144 hypomethylated. The descriptive analysis of these genes by Gene Ontology (GO), KEGG pathway and protein domain analyses points to pathways of development and differentiation. We identified a list of genes which are differently methylated in mild and severe OA cartilage. Within the pathways of growth and development new therapeutic targets might arise by improving our understanding of pathogenetic mechanisms in OA.

Whole body hyperthermia treatment increases interleukin 10 and toll-like receptor 4 expression in patients with ankylosing spondylitis: a pilot study.

PURPOSE: Exposure to increased environmental temperatures is commonly used as a non-pharmacological treatment modality in ankylosing spondylitis (AS). We aimed to investigate systemic immunological effects of moderate whole body hyperthermia in patients with AS compared to healthy control subjects. MATERIALS AND METHODS: Ten healthy control subjects and six AS patients underwent whole body hyperthermia treatment with 38.7-39 °C body core temperature over 60 min. Numbers of polymorphonuclear leucocytes and lymphocyte subsets, plasma concentrations of several acute phase reactants and cytokines, and gene expression levels of toll-like receptor 4 (TLR-4), interleukin 10 (IL-10) and heat shock protein beta 1 (HSPB1) were determined during and up to 24 h after treatment. RESULTS: TLR-4, IL-10 and HSPB1 gene expression increased significantly up to 3 h post treatment, with an earlier, higher and more pronounced increase of IL-10 in patients with AS. An increase of natural killer cells and CD8+ T lymphocytes was noted during active heating, with a subsequent decrease up to 2 h after treatment. CD4+ T lymphocytes showed a short increase during active treatment in AS patients, while decreasing immediately after start of treatment in control subjects. Neutrophil granulocytes increased significantly up to 3 h after treatment, monocytes and B lymphocytes remained unchanged. Likewise, no significant changes were found concerning systemic cytokine concentrations and acute phase reactants. CONCLUSIONS: Our data support the concept of systemic immunological effects of moderate whole body hyperthermia in patients with AS.

Sphingosine 1-phosphate counteracts the effects of interleukin-1ß in human chondrocytes.

OBJECTIVE: The lipid mediator sphingosine 1-phosphate (S1P) is found in the synovial fluid of osteoarthritis (OA) patients. S1P protects bovine cartilage by counteracting the effects of interleukin-1ß (IL-1ß). This study was undertaken to examine the interaction of S1P and IL-1ß in human OA chondrocytes. METHODS: Human cartilage was obtained from patients undergoing total knee joint replacement. Chondrocytes were cultured in monolayer and treated with IL-1ß and S1P. Expression of S1P receptor subtypes and genes involved in cartilage degradation was evaluated using real-time polymerase chain reaction, immunohistochemistry, and Western blotting. S1P signaling was evaluated using inhibitors of S1P receptors and small interfering RNA (siRNA) knockdown of the S1P2 receptor. Phosphorylation of MAP kinases and NF-κB in response to IL-1ß and S1P was detected by Western blotting. RESULTS: S1P2 was identified as the most prevalent S1P receptor subtype in human OA cartilage and chondrocytes in vitro. S1P reduced expression of inducible nitric oxide synthase (iNOS) in IL-1ß-treated chondrocytes. Reduction of ADAMTS-4 and matrix metalloproteinase 13 expression by S1P correlated with S1P2 expression. Pharmacologic inhibition of the S1P2 receptor, but not the S1P1 and S1P3 receptors, abrogated the inhibition of iNOS expression. Similar results were observed using siRNA knockdown. S1P signaling inhibited IL-1ß-induced phosphorylation of p38 MAPK. CONCLUSION: In human chondrocytes, S1P reduces the induction of catabolic genes in the presence of IL-1ß. Activation of the S1P2 receptor counteracts the detrimental phosphorylation of p38 MAPK by IL-1ß.

Mathematical modeling of poly[(R)-3-hydroxyalkanoate] synthesis by Cupriavidus necator DSM 545 on substrates stemming from biodiesel production.

Two low structured mathematical models for fed-batch production of polyhydroxybutyrate and poly[hydroxybutyrate-co-hydroxyvalerate] by Cupriavidus necator DSM 545 on renewable substrates (glycerol and fatty acid methyl esters-FAME) combined with glucose and valeric acid, were established. The models were used for development/optimization of feeding strategies of carbon and nitrogen sources concerning PHA content and polymer/copolymer composition. Glycerol/glucose fermentation featured a max. specific growth rate of 0.171 h(-1), a max. specific production rate of 0.038 h(-1) and a PHB content of 64.5%, whereas the FAME/valeric acid fermentation resulted in a max. specific growth rate of 0.046 h(-1), a max. specific production rate of 0.07 h(-1) and 63.6% PHBV content with 4.3% of 3-hydroxyvalerate (3HV) in PHBV. A strong inhibition of glycerol consumption by glucose was confirmed (inhibition constant ki,G=4.28×10(-4) g L(-1)). Applied concentration of FAME (10-12 g L(-1)) positively influenced on PHBV synthesis. HV/PHBV ratio depends on applied VA concentration.

Histamine contributes to increased RANKL to osteoprotegerin ratio through altered nuclear receptor 4A activity in human chondrocytes.

OBJECTIVE: To elucidate histamine receptor-mediated signaling pathways, transcriptional events, and target gene expression in human cartilage. METHODS: Histamine modulation of cartilage destruction was assessed by Safranin O staining and proteoglycan release. H(1) , H(2) , H(3) , and H(4) histamine receptor-dependent regulation of transcription factors (nuclear receptor 4A1 [NR4A1], NR4A2, and NR4A3), RANKL, and osteoprotegerin (OPG) messenger RNA (mRNA) levels were measured in primary and SW-1353 chondrocyte cells using quantitative polymerase chain reaction and selective histamine receptor antagonists. Soluble RANKL and OPG protein levels were determined using enzyme-linked immunosorbent assays. NR4A protein levels and transactivity were evaluated by Western blot analysis, immunocytochemistry, and luciferase reporter assays. Stable depletion of NR4A1-3 was achieved by lentiviral transduction of NR4A short hairpin RNA. RESULTS: Primary human chondrocyte cells expressed differential steady-state levels of H(1) -H(4) histamine receptor mRNA. In combination with tumor necrosis factor α, histamine significantly promoted cartilage proteoglycan depletion and release. Histamine modulated the expression of NR4A1-3 orphan receptors in primary and immortalized human chondrocyte cells in a time- and concentration-dependent manner. Histamine selectively signaled through H(1) and H(2) histamine receptors in chondrocytes to modulate RANKL and NR4A2 expression. The temporal effects of histamine on NR4A2 gene transcription were reduced in cells pretreated with inhibitors directed against protein kinase A, MAPK, and NF-κB signaling pathways. Histamine modulated the expression of RANKL with modest effects on OPG levels, leading to increased RANKL:OPG mRNA and protein ratios. Stable knockdown of NR4A1-3 expression resulted in reduced endogenous OPG levels and the loss of histamine-dependent regulation of RANKL expression. CONCLUSION: Our findings indicate that histamine, via H(1) and H(2) histamine receptors, contributes to joint disease by enhancing the ratio of RANKL to OPG expression through altered NR4A activity in human chondrocyte cells.

The nuclear orphan receptors NR4A as therapeutic target in cancer therapy.

NR4A1 (Nur77), NR4A2 (Nurr1) and NR4A3 (Nor-1) are three members of the orphan nuclear receptor (NR) family referred to as NR4A family. This subgroup activates gene expression in a constitutive ligand-independent manner. These nuclear receptors are classified as early response genes that are induced by a diverse range of signals. These orphan NRs have been implicated in cell cycle regulation, apoptosis, inflammation, metabolism and more recently in carcinogenesis. The ultimate growth of a tumor depends not only on the rate of tumor cell proliferation, but also the rate of apoptosis and NR4A1 controls both, survival and death of cancer cells. It has been demonstrated that NR4A1 activities are regulated through its subcellular localisation. In the nucleus, NR4A1 can function in a context dependent manner either as an oncogenic survival factor, promoting cancer cell growth or as the opposite through the activation of apoptosis. Additionally, in an atypical fashion, it is a potent killer when migrating to the mitochondria, where it binds to Bcl-2 and converts its survival phenotype, triggering cytochrome c release and apoptosis. The most convincing evidence that nuclear orphan receptors function as critical tumor suppressors is the observation that the NR4A1 and NR4A3 double knock out mouse develops rapidly acute myeloid leukemia. Down regulation of NR4A1 and NR4A3 was a common feature in leukemic blasts from human AML patients. In particular, the recent identification of pro-apoptotic agents inducing NR4A expression or acting as agonists suggests that these members could serve as potential targets for cancer therapy.

The immunosuppressant FTY720 (fingolimod) enhances glycosaminoglycan depletion in articular cartilage.

BACKGROUND: FTY720 (Fingolimod) is a novel immunosuppressive drug investigated in clinical trials for organ transplantation and multiple sclerosis. It acts as a functional sphingosine-1-phosphate (S1P) receptor antagonist, thereby inhibiting the egress of lymphocytes from secondary lymphoid organs. As S1P is able to prevent IL-1beta induced cartilage degradation, we examined the direct impact of FTY720 on cytokine induced cartilage destruction. METHODS: Bovine chondrocytes were treated with the bioactive phosphorylated form of FTY720 (FTY720-P) in combination with IL-1beta or TNF-alpha. Expression of MMP-1,-3.-13, iNOS and ADAMTS-4,-5 and COX-2 was evaluated using quantitative real-time PCR and western blot. Glycosaminoglycan depletion from cartilage explants was determined using a 1,9-dimethylene blue assay and safranin O staining. RESULTS: FTY720-P significantly reduced IL-1beta and TNF-alpha induced expression of iNOS. In contrast FTY720-P increased MMP-3 and ADAMTS-5 mRNA expression. Furthermore depletion of glycosaminoglycan from cartilage explants by IL-1beta and TNF-alpha was significantly enhanced by FTY720-P in an MMP-3 dependent manner. CONCLUSIONS: Our results suggest that FTY720 may enhance cartilage degradation in pro-inflammatory environment.