Health and frailty among older spousal caregivers: an observational cohort study in Belgium.

Background: Among older couples, spouses are first in line to provide care, and they are key elements in the home support of dependent older persons. In this context, ensuring the health of these older spousal caregivers should be an important issue for all of the providers who care for older adults. The aim of this study was to longitudinally assess the health of older spousal caregivers considering frailty, nutrition, cognition, physical performance and mood disorders.

Growth Hormone (GH) Deficient Mice With GHRH Gene Ablation Are Severely Deficient in Vaccine and Immune Responses Against .

The precise impact of the somatotrope axis upon the immune system is still highly debated. We have previously shown that mice with generalized ablation of growth hormone (GH) releasing hormone (GHRH) gene () have normal thymus and T-cell development, but present a marked spleen atrophy and B-cell lymphopenia. Therefore, in this paper we have investigated vaccinal and anti-infectious responses of mice against , a pathogen carrying T-independent antigens.

The Somatotrope Growth Hormone-Releasing Hormone/Growth Hormone/Insulin-Like Growth Factor-1 Axis in Immunoregulation and Immunosenescence.

Most scientific reports debate the thymotropic and immuno-stimulating properties of the somatotrope growth hormone-releasing hormone (GHRH)/growth hormone (GH)/insulin-like growth factor (IGF)-1 axis, but there is still some disagreement about the physiological role of this axis in basal conditions. Moreover, some authors have hypothesized that the physiological role of the somatotrope axis only appears in stressful conditions (such as sepsis or infective and inflammatory diseases). This chapter will provide an extended overview of the expression of the components (signals and receptors) of the somatotrope axis and their properties on cells of the innate and adaptive immune system.

Programming of neuroendocrine self in the thymus and its defect in the development of neuroendocrine autoimmunity.

For centuries after its first description by Galen, the thymus was considered as only a vestigial endocrine organ until the discovery in 1961 by Jacques FAP Miller of its essential role in the development of T (thymo-dependent) lymphocytes. A unique thymus first appeared in cartilaginous fishes some 500 million years ago, at the same time or shortly after the emergence of the adaptive (acquired) immune system. The thymus may be compared to a small brain or a computer highly specialized in the orchestration of central immunological self-tolerance.

Evidence for cross-talk between the LH receptor and LH during implantation in mice.

The present study investigated the first interaction that occurs between the blastocyst and endometrium during implantation. Given the ethical objections to studying implantation in humans, a mouse model was used to study the dialogue between luteinising hormone (LH) and luteinising hormone receptor (LHCGR). Several studies performed on LHCGR-knockout mice have generated controversy regarding the importance of the dialogue between LH and LHCGR during implantation.

Aire and Foxp3 expression in a particular microenvironment for T cell differentiation.

Objective: The thymus is the primary lymphoid organ responsible for T cell development and the establishment of central self-tolerance. Among thymic epithelial cells, thymic nurse cells (TNC) interact closely with immature thymocytes and constitute a special microenvironment for T cell differentiation and selection. In addition, TNC express neuroendocrine self-antigens such as oxytocin and insulin-like growth factor-2, whose intrathymic transcription is regulated by the autoimmune regulator gene/protein (Aire).

Dialogue between blastocyst hCG and endometrial LH/hCG receptor: which role in implantation?

The specific interaction of blastocyst-derived human chorionic gonadotropin (hCG) and endometrial LH/hCG-R constitutes a fundamental component of the molecular dialogue at the materno-fetal interface. From our observations and studies from other groups, hCG was indeed shown to play a significant role in implantation and tolerance of the embryo, decidual differentiation and remodeling, as well as in placentation. The profile pattern of LH/hCG-R expression by endometrial epithelium correlates with the theoretical timing of the implantation window.

[What's new at the maternal-foetal interface: role of the hCG/LH-hCG receptor couple during embryo implantation].

Implantation of the embryo into the maternal endometrium represents a unique biological process, combining an immunological (tolerance of an allograft) and biological (adhesion of two epitheliums) paradox. The success of implantation depends on a receptive endometrium, a functionally normal blastocyst and a synchronized cross-talk between embryonic and maternal tissues. Though sexual steroids control the process, a cascade of growth factors or cytokines are the prime paracrine mediators of the dialogue at the maternal-embryonic interface.

Human endometrial leukemia inhibitory factor and interleukin-6: control of secretion by transforming growth factor-beta-related members.

Objective(s): The implantation process is closely linked to the fundamental question of the tolerance of the maternal immune system. The main objective of this study was to investigate whether different members of the transforming growth factor-beta (TGF-beta) superfamily could intervene in the first steps of embryo implantation by modulating the secretion of proimplantatory leukemia inhibitory factor (LIF) and in the tolerance of the fetal graft by regulating proinflammatory interleukin (IL)-6 secretion by human endometrial epithelium (EEC) in vitro.

Methods: EEC were isolated from biopsies collected from 16 informed and consenting fertile women and were cultured for 72 h.

Human chorionic gonadotropin and growth factors at the embryonic-endometrial interface control leukemia inhibitory factor (LIF) and interleukin 6 (IL-6) secretion by human endometrial epithelium.

Background: The elucidation of the molecular mechanisms by which the embryo contributes to its implantation is an area of extensive research. The main objective of this study was to investigate the pattern of leukemia inhibitory factor (LIF) and interleukin-6 (IL-6) secretion by human endometrial epithelium, and their regulation by human chorionic gonadotropin (hCG) and other growth factors present at the embryonic-endometrial interface.

Methods: Endometrial epithelial cells (EEC) were isolated from biopsies collected at both proliferative and secretory phases of fertile women.

Neurohypophysial receptor gene expression by thymic T cell subsets and thymic T cell lymphoma cell lines.

Neurohypophysial oxytocin (OT) and vasopressin (VP) genes are transcribed in thymic epithelium, while immature T lymphocytes express functional neurohypophysial receptors. Neurohypophysial receptors belong to the G protein-linked seven-transmembrane receptor superfamily and are encoded by four distinct genes, OTR, V1R, V2R and V3R. The objective of this study was to identify the nature of neurohypophysial receptor in thymic T cell subsets purified by immunomagnetic selection, as well as in murine thymic lymphoma cell lines RL12-NP and BW5147.

[The implantation window].

Background: Embryo implantation is a complex event involving apposition followed by adhesion of the blastocyst to the maternal endometrium, and finally invasion of this endometrium. Though implantation could occur in any human tissue, the endometrium is the only tissue where embryo implantation cannot occur except during a restricted period called the implantation window. During this window, the endometrium is highly receptive to the embryo.

Persistent infection of human thymic epithelial cells by coxsackievirus B4.

Persistent replication of coxsackievirus B4 (CVB4) E2 (diabetogenic) and CVB4 JBV (nondiabetogenic) strains in thymic epithelial cell (TEC)-enriched cultures (>or=95%) was proved by detection of positive- and negative-strand viral RNA by reverse transcription-PCR in extracted RNA from cell cultures, VP1 capsid protein detection by immunofluorescence (IF) staining, and release of infectious particles up to 30 days after infection without obvious cytolysis. By double-IF staining, cytokeratin-containing cells were shown to be susceptible to CVB4. The persistence of CVB4 was associated with a significantly increased rate of TEC proliferation (up to 70%) after 20 days of culture and a significantly increased chronic production of immunoreactive interleukin-6 (IL-6), leukemia inhibitory factor, and granulocyte-macrophage colony-stimulating factor in supernatant after 3 days of culture.

Characterization of the insulin-like growth factor axis in the human thymus.

The components of the insulin-like growth factor (IGF) axis have been investigated in the normal human thymus. Using ribonuclease protection assays (RPA), IGF-II transcripts were detected in the normal human thymus. By reverse transcriptase polymerase chain reaction (RT-PCR) analyses, promoters P3 and P4 were found to be active in the transcription of IGF2 gene within human thymic epithelial cells (TEC).

The thymic repertoire of neuroendocrine-related self antigens: biological role in T-cell selection and pharmacological implications.

Thymic epithelium, including nurse cells (TEC/TNC), as well as other thymic stromal cells (macrophages and dentritic cells), express a repertoire of polypeptide belonging to various neuroendocrine protein families (such as the neurophypophysial, tachykinin, neurotensin and insulin families). A hierarchy of dominance exists in the organization of the thymic repertoire of neuroendocrine precursors. Oxytocin (OT) is more expressed in the TEC/TNC than vasopressin (VP); insulin-like growth factor 2 (IGF-2) thymic expression predominates over IGF-1, and much more over (pro)insulin.

Neurohypophysial peptides stimulate the phosphorylation of pre-T cell focal adhesion kinases.

Thymic oxytocin (OT) behaves as a cryptocrine signal targeted at the outer surface of thymic epithelial cell plasma membrane from where OT is able to interact with neurohypophysial peptide receptors expressed by pre-T cells. Immature T cells bear a receptor of the V1 subtype, while OT receptors are predominantly expressed by cytotoxic CD8+ lymphocytes. In both T cell types, neurohypophysial peptide receptors transduce OT via the phosphoinositide pathway.

Effects of a novel gonadotropin-releasing hormone antagonist (ORG 30850) on gonadotropin and prolactin secretion by rat pituitary cells in culture.

The effect of a new GnRH antagonist (ORG 30850 ANT) on FSH, LH, and PRL secretion was studied using male rat pituitary cells in monolayer cell culture. In the absence of GnRH, ORG 30850 ANT did not alter spontaneous FSH and LH secretion into culture medium or the cell content of these hormones. In the presence of GnRH (10(-8) mol/l), ORG 30850 ANT significantly and dose-dependently inhibited FSH and LH secretion into culture medium while increasing their cell content.

Correlation between follicular fluid content and the results of in vitro fertilization and embryo transfer. II. Inhibin and aromatase inhibitor activity.

The inhibin content and aromatase inhibitor activity (AIA) of 72 follicular fluids (FF) obtained from 42 women undergoing in vitro fertilization (IVF) and embryo transfer (ET) were studied as a function of IVF ET outcome. Inhibin levels were determined by bioassay (BA) and RIA; AIA was measured by BA. The inhibin content of follicles characterized as immature by their estradiol (E2) levels and E2/progesterone (P) ratios was significantly lower (P less than 0.

Inhibin and related peptides: mechanisms of action and regulation of secretion.

The structure of inhibin is known; it consists of a heterodimer composed of one alpha and one beta subunit. The homodimer of beta A (beta A-beta A) and the heterodimer beta A-beta B, called activin A and B, respectively, stimulate the release and synthesis of FSH by gonadotrophs. Inhibin exerts effects at the hypophyseal, hypothalamic, and gonadal levels.

Inhibin and related peptides. Mechanisms of action and regulation of secretion.

The structure of inhibin is known: it consists in a heterodimer constituted by one alpha and one beta subunits. The homodimer of beta A or the heterodimer beta A or the heterodimer beta A-beta B called activin A and B stimulates the release and the synthesis of FSH by gonadotrophs. Inhibin displays actions at hypophyseal, hypothalamic and gonadal levels.

Effect of mouse epidermal growth factor on DNA and protein synthesis, progesterone and inhibin production by bovine granulosa cells in culture.

The effect of mouse epidermal growth factor (EGF) was investigated on DNA and protein synthesis, progesterone and inhibin production by bovine antral granulosa cells. When incubated for the whole period of culture, EGF inhibited inhibin production the second day of culture, progesterone the third and the fourth days whereas it stimulated DNA and protein synthesis only the fourth day of culture. Inhibition of progesterone and stimulation of DNA and protein were dose-dependent when treatment with EGF (pre-incubation) is followed by 24 h without EGF, a stimulatory effect on DNA and protein synthesis was observed after 48 and 72-h pre-incubation.

Effect of follicular atresia on inhibin production by bovine granulosa cells in vitro and inhibin concentrations in the follicular fluid.

The ability of bovine granulosa cells to produce inhibin and to synthesize oestradiol-17 beta increased with increasing follicle size in healthy but not atretic follicles. Granulosa cells from small (less than or equal to 5 mm diam.) healthy follicles were indistinguishable from cells of atretic follicles in terms of their ability to produce inhibin and to aromatize androgen.

Effect of neuraminidase on inhibin activity in vivo and in vitro.

Matrex gel red A purified follicular fluid has been used to study whether or not this material contains sialic acid residues and their importance in maintaining the biological activity of inhibin both in vitro and in vivo. It appears that sialic acid is present in these preparations and can be released either by neuraminidase treatment of acid hydrolysis. The addition of intact and desialylated inhibin-containing material to isolated rat pituitary cells in culture gives similar inhibition of LHRH-induced FSH release of these cells indicating that sialic acid is not required for inhibin activity in vitro.