Machine Learning for personalised stress detection: Inter-individual variability of EEG-ECG markers for acute-stress response.

Stress appears as a response for a broad variety of physiological stimuli. It does vary among individuals in amplitude, phase and frequency. Thus, the necessity for personalised diagnosis is key to prevent stress-related diseases. In order to evaluate stress levels, a multi-sensing system is proposed based on non-invasive EEG and ECG signals. A target population of 24 individuals which age range between 18-23 years old are intentionally exposed to control-induced stress tests while EEG and ECG are simultaneously recorded. The acquired signals are processed by using semisupevised Machine Learning techniques as those provide a patient-specific approach due to key characteristics such as adaptiveness and robustness. In here, a stress metric is proposed that jointly with each individual medical history provide mechanisms to prevent and avoid possible chronic-health issues for individuals whom are more sensitive to stressors. Finally, supervised learning techniques are used to classify the obtained featured clusters to evaluate specific and general subject models in order to pave the way for real time stress monitoring.

Metabolic Pathway Analysis of Nitrogen and Phosphorus Uptake by the Consortium between C. vulgaris and P. aeruginosa.

Anthropogenic activities have increased the amount of urban wastewater discharged into natural aquatic reservoirs containing a high amount of nutrients such as phosphorus (Pi and PO 4 - 3 ), nitrogen (NH 3 and NO 3 - ) and organic contaminants. Most of the urban wastewater in Mexico do not receive any treatment to remove nutrients. Several studies have reported that an alternative to reduce those contaminants is using consortiums of microalgae and endogenous bacteria. In this research, a genome-scale biochemical reaction network is reconstructed for the co-culture between the microalga Chlorella vulgaris and the bacterium Pseudomonas aeruginosa. Metabolic Pathway Analysis (MPA), is applied to understand the metabolic capabilities of the co-culture and to elucidate the best conditions in removing nutrients. Theoretical yields for phosphorus removal under photoheterotrophic conditions are calculated, determining their values as 0.042 mmol of PO 4 - 3 per g DW of C. vulgaris, 19.43 mmol of phosphorus (Pi) per g DW of C. vulgaris and 4.90 mmol of phosphorus (Pi) per g DW of P. aeruginosa. Similarly, according to the genome-scale biochemical reaction network the theoretical yields for nitrogen removal are 10.3 mmol of NH 3 per g DW of P. aeruginosa and 7.19 mmol of NO 3 - per g DW of C. vulgaris. Thus, this research proves the metabolic capacity of these microorganisms in removing nutrients and their theoretical yields are calculated.

Effects of local activation and blockade of dopamine D4 receptors in the spiking activity of the reticular thalamic nucleus in normal and in ipsilateral dopamine-depleted rats.

The reticular thalamic nucleus (RTn) controls the overall activity of thalamo-cortical neurons information processing. GABAergic RTn neurons have one of the highest densities of D4-type dopamine receptors in subcortical structures. The unitary electrical activity of RTn neurons was recorded in vivo in Wistar rats in order to study the effects of local activation and blockade of D4 receptors under both conditions, normal and ipsilateral lesion of the dopaminergic pathways. Our data suggest that: i) there is a tonic dopaminergic input to the RTn; ii) local activation of D4 receptors increases the basal firing rate of RTn neurons in normal and lesioned rats, and iii) local blockade of D4 receptors diminishes the firing rate in normal but not in lesioned rats. Altogether, our findings support that dopamine contributes to the spontaneous basal firing of the RTn neurons through D4-type dopamine receptors.

Taking stock of Roma health policies in Spain: Lessons for health governance.

Roma health inequities are a wicked problem. Despite concerted efforts to reduce them under the Decade of Roma Inclusion initiative, the health gap between Roma and non-Roma populations in Europe persists. To address this problem, the European Commission devised the National Roma Integration Strategies (NRIS). This paper provides a critical assessment of the implementation of the NRIS' health strand (NRIS-H) in Spain and proposes an evaluation tool to monitor Roma health policies - the Roma Health Integration Policy Index (RHIPEX). It also makes recommendations to promote Roma health governance. To achieve these goals, four community forums, 33 stakeholder interviews and a scoping review were conducted. Results show that the NRIS-H implementation is hindered by lack of political commitment and poor resource allocation. This has a negative impact on Roma's entitlement to healthcare and on their participation in decision-making processes, jeopardising the elimination of the barriers that undermine their access to healthcare and potentially contributing to reproduce inequalities. These unintended effects point out the need to rethink Roma health governance by strengthening intersectional and intersectoral policies, enabling transformative Roma participation in policymaking and guaranteeing shared socio-political responsibility and accountability.

[Comparison of set-up control for head and neck patients between radiation oncologist and therapists with the aim of partial delegation]. / Comparaison des contrôles de position de patients atteints de cancer ORL entre médecin et manipulateurs en vue d'une délégation partielle.

PURPOSE: The aim of this prospective study was to evaluate daily set-up by a radiation oncologist and by radiation therapists using on-board imaging of patients with head and neck cancer in order to calculate margin to PTV (planning target volume) and intent partial delegation of positioning images control. PATIENTS AND METHODS: The files of 11 patients with head and neck cancer treated on a Synergy™ (Elekta™) accelerator with on-board imaging system were evaluated. Daily kV-kV images were double-blind reviewed by radiation therapists (7 participants) and by one radiation oncologist. The radiation oncologist's measures were used for margin calculation from CTV to PTV. The difference of measures and the concordance of decisions between radiation therapists and the radiation oncologist were calculated. RESULTS: The 325 measures made by the radiation oncologist resulted in a margin of 5mm to be applied to the CTV in each direction. Nine hundred seventy-seven measures were made by the radiation oncologist and radiation therapists with a difference of 3mm or less in 98.46%. The concordance of decision for a 4mm difference or less to the isocenter was 96.7%. CONCLUSION: This study confirms the 5mm PTV margin mostly used in ORL. The small gap between the radiation oncologist's and therapists' measures allows a partial delegation of positioning images control.

Proteomic analysis of cerebrospinal fluid from obese women with idiopathic intracranial hypertension: a new approach for identifying new candidates in the pathogenesis of obesity.

Body weight control is tightly regulated in the hypothalamus. The inaccessibility of human brain tissue can be partially solved by using cerebrospinal fluid (CSF) as a tool for assessing the central nervous system's production of orexigen and anorexigen factors. Using proteomic analysis, the present study investigated the differentially displayed proteins in human CSF from obese and non-obese subjects. We designed a case-control study conducted in a reference hospital where eight obese (cases) and eight non-obese (controls) women with idiopathic intracranial hypertension were included. Intracranial hypertension was normalised through the placement of a ventriculo- or lumboperitoneal shunt in the 12 months before their inclusion in the study. Isotope-coded protein label (for proteins > 10 kDa) and label-free liquid chromatography (for proteins < 10 kDa) associated with mass spectrometry analysis were used. Eighteen differentially expressed proteins were identified. Many of them fall into three main groups: inflammation (osteopontin, fibrinogen γ and ß chain, α1 acid glycoprotein 2 and haptoglobin), neuroendocrine mediators (neurosecretory protein VGF, neuroendocrine protein 7B2, chromogranin-A and chromogranin B), and brain plasticity (testican-1, isoform 10 of fibronectin, galectin-3 binding protein and metalloproteinase inhibitor type 2). The differential production of osteopontin, neurosecretory protein VGF, chromogranin-A and fibrinogen γ chain was further confirmed by either enzyme-linked immunosorbent assay or western blotting. In conclusion, we have identified potential candidates that could be involved in the pathogenesis of obesity. Further studies aiming to investigating the precise role of these proteins in the pathogenesis of obesity and their potential therapeutic implications are needed.

Fenofibric acid prevents retinal pigment epithelium disruption induced by interleukin-1ß by suppressing AMP-activated protein kinase (AMPK) activation.

AIMS/HYPOTHESIS: The mechanisms involved in the beneficial effects of fenofibrate on the development and progression of diabetic macular oedema (DMO) remain to be elucidated. To shed light on this issue we have explored the effect of fenofibric acid on the barrier function of human retinal pigment epithelium (RPE) cells. METHODS: ARPE-19 cells (a human RPE line) were cultured for 18 days under standard conditions and under conditions leading to the disruption of the monolayer (D-glucose, 25 mmol/l, with IL-1ß, 10 ng/ml, added at days 16 and 17). Fenofibric acid, 25 µmol/l and 100 µmol/l, was added on the last 3 days of the experiment (one application/day). RPE cell permeability was evaluated by measuring apical-basolateral movements of FITC-dextran (40 kDa). The production of tight junction proteins and AMP-activated protein kinase (AMPK) phosphorylation was assessed by western blot. Immunohistochemical studies of tight junction proteins and small interfering RNA transfection to AMPK were also performed in ARPE-19 monolayers. RESULTS: Treatment of ARPE-19 cells with fenofibric acid significantly reduced the increment of permeability and the breakdown of the ARPE-19 cell monolayer induced by D-glucose, 25 mmol/l, and IL-1ß, 10 ng/ml, in a dose-dependent manner. This effect was unrelated to changes in the content of tight junction proteins. Fenofibric acid prevented the activation of AMPK induced by IL-1ß and the hyperpermeability induced by IL-1ß was blocked by silencing AMPK. CONCLUSIONS/INTERPRETATION: Disruption of RPE induced by IL-1ß is prevented by fenofibric acid through its ability to suppress AMPK activation. This mechanism could be involved in the beneficial effects of fenofibrate on DMO development.

Pre-synaptic histamine H3 receptors modulate glutamatergic transmission in rat globus pallidus.

The globus pallidus, a neuronal nucleus involved in the control of motor behavior, expresses high levels of histamine H(3) receptors (H(3)Rs) most likely located on the synaptic afferents to the nucleus. In this work we studied the effect of the activation of rat pallidal H(3)Rs on depolarization-evoked neurotransmitter release from slices, neuronal firing rate in vivo and turning behavior. Perfusion of globus pallidus slices with the selective H(3)R agonist immepip had no effect on the release of [(3)H]-GABA ([(3)H]-γ-aminobutyric acid) or [(3)H]-dopamine evoked by depolarization with high (20 mM) K(+), but significantly reduced [(3)H]-d-aspartate release (-44.8 ± 2.6% and -63.7 ± 6.2% at 30 and 100 nM, respectively). The effect of 30 nM immepip was blocked by 10 µM of the selective H(3)R antagonist A-331440 (4'-[3-[(3(R)-dimethylamino-1-pyrrolidinyl]propoxy]-[1,1-biphenyl]-4'-carbonitrile). Intra-pallidal injection of immepip (0.1 µl, 100 µM) decreased spontaneous neuronal firing rate in anaesthetized rats (peak inhibition 68.8±10.3%), and this effect was reversed in a partial and transitory manner by A-331440 (0.1 µl, 1 mM). In free-moving rats the infusion of immepip (0.5 µl; 10, 50 and 100 µM) into the globus pallidus induced dose-related ipsilateral turning following systemic apomorphine (0.5 mg/kg, s.c.). Turning behavior induced by immepip (0.5 µl, 50 µM) and apomorphine was partially prevented by the local injection of A-331440 (0.5 µl, 1 mM) and was not additive to the turning evoked by the intra-pallidal injection of antagonists at ionotropic glutamate receptors (0.5 µl, 1 mM each of AP-5, dl-2-amino-5-phosphonovaleric acid, and CNQX, 6-nitro-7-sulphamoylbenzo[f]quinoxaline-2,3-dione). These results indicate that pre-synaptic H(3)Rs modulate glutamatergic transmission in rat globus pallidus and thus participate in the control of movement by basal ganglia.

Management of obstructive renal failure caused by bilateral renal aspergilloma in an immunocompetent newborn.

Fungal infection of the kidneys is a rare condition that has been reported in premature babies and in diabetic or immunocompromised adult patients. Candida spp. is the most frequent micro-organism involved. This paper reports a case of an immunocompetent newborn with a bladder exstrophy who suffered from an acute renal failure caused by bilateral renal aspergilloma (Aspergillus flavus). The newborn was treated with amphotericin B urinary tract irrigation through bilateral nephrostomy catheters, combined with liposomal amphotericin B and voriconazole therapy, which improved his renal function. However, due to persistent fungal colonization, a long antifungal treatment and permanent ureterostomies were necessary to deal with new episodes of ureterorenal obstruction. As of November 2009, despite the renal injuries, renal function had been conserved. The management of the mechanical obstruction and the choice of antifungal drugs are discussed in this unusual case.

Interphotoreceptor retinoid-binding protein (IRBP) is downregulated at early stages of diabetic retinopathy.

AIMS/HYPOTHESIS: Interphotoreceptor retinoid-binding protein (IRBP) plays a major role in the visual cycle and is essential to the maintenance of photoreceptors. The aim of this study was to determine whether a decrease in IRBP production exists in the early stages of diabetic retinopathy. METHODS: Vitreous samples from diabetic patients with proliferative and non-proliferative diabetic retinopathy (PDR, NPDR), and from non-diabetic patients with macular hole (control group) were selected for IRBP quantitative assessment by proteomic analysis (fluorescence-based difference gel electrophoresis) and western blot. Human post mortem eyes (n = 16) from diabetic donors without clinically detectable retinopathy and from non-diabetic donors (n = 16) were used to determine IRBP (also known as RBP3) mRNA levels (RT-PCR) and protein content (western blot and confocal microscopy). Retinal neurodegeneration was assessed by measuring glial fibrillar acidic protein (GFAP) and the apoptotic rate. Y79 human retinoblastoma cells were used to test the effects of glucose, TNF-alpha and IL-1beta on IRBP expression and IRBP levels. RESULTS: Intravitreous IRBP concentration was significantly lower in PDR < NPDR < control in proteomic and western blot analysis. IRBP mRNA levels and IRBP protein content were significantly lower in the retinas from diabetic donors than in those from non-diabetic donors. Increased GFAP and a higher degree of apoptosis were observed in diabetic retinas compared with non-diabetic retinas. A dose-dependent downregulation of IRBP mRNA expression and IRBP content was detected with glucose, TNF-alpha and IL-1beta in cultures of Y79 human retinoblastoma cells. CONCLUSIONS/INTERPRETATION: Underproduction of IRBP is an early event in the human diabetic retina and is associated with retinal neurodegeneration. The mechanisms leading to this deficit deserve further investigation.

[Genetic and clinical diagnosis of Angelman syndrome. Case Reviews]. / Síndrome de Angelman: diagnóstico genético y clínico. Revisión de nuestra casuística.

INTRODUCTION: Angelman syndrome is characterised by mental retardation, epilepsy, speech impairment, facial dysmorphism and a characteristic behavioural phenotype. Diagnostic clinical criteria have been defined by consensus since 1995. It is caused by deficiency or inactivation of the UB3A gene. There is a percentage of cases which satisfy these clinical features but have negative genetic testing. We consider it necessary to analyse the patient characteristics and possible phenotype-genotype correlations. MATERIAL AND METHODS: All cases which were treated between 1981 and 2007 in a neurology unit and fulfilled the clinical criteria were included. Genetic diagnosis was made by methylation testing and fluorescent in situ hybridization. RESULTS: Thirteen patients were studied, nine with positive genetic testing and four with negative testing who completed the clinical criteria. The average age at diagnosis was 37 months. Eleven cases showed acquired microcephaly. Flat occiput, mouth and maxillary malformations, hypopigmentation, a happy appearance and hyperactivity were practically constant characteristics. Speech and walking ability were the areas which showed most deficit. Twelve cases had epilepsy. Three of the cases with normal genetic testing showed less microcephaly and better psychomotor development, particularly in walking ability. CONCLUSIONS: The phenotypical characteristics of the syndrome should be known before requesting specific genetic testing and to make a diagnosis even in cases with negative genetic. The phenotype characteristics that describe Angelman syndrome were verified. Deletion cases had a worse outcome.

Mitochondrial DNA oxidation and manganese superoxide dismutase activity in peripheral blood mononuclear cells from type 2 diabetic patients.

AIM: To investigate the balance between parameters of oxidative stress and antioxidant defences in the mitochondria of peripheral blood mononuclear cells (PBMCs) of type 2 diabetic patients with late complications. METHODS: Ten type 2 diabetic patients with late diabetic complications and 10 age-matched healthy volunteers (controls) were prospectively recruited. Mitochondrial DNA (mtDNA) oxidative damage and mtDNA content were measured as indices of oxidative stress. Manganese superoxide dismutase (MnSOD) activity has been used as an index of mitochondrial antioxidant defence. Mitochondrial respiratory-chain function (cytochrome C oxidase activity) was also assessed. RESULTS: Mitochondrial DNA (mtDNA) oxidation was significantly higher in the PBMCs of diabetic patients than in control subjects (P<0.0001) and, although mtDNA content was lower in the diabetic group, this was not statistically significant. MnSOD activity was significantly increased in PBMCs of type 2 diabetic patients compared with healthy controls (1366+/-187 versus 686+/-167 U/g of protein; P=0.01), and was related to mtDNA oxidative damage. No differences in mitochondrial respiratory-chain function were found between diabetic patients and controls. CONCLUSION: PMBCs from type 2 diabetic patients with late diabetic complications exhibit high mtDNA oxidative damage. The degree of mtDNA oxidation was associated with an increase in MnSOD as an adaptive response to oxidative stress. The consequences of mtDNA oxidative damage on PBMC function and the progression of diabetic complications remain to be elucidated.

Proteomic analysis of human vitreous fluid by fluorescence-based difference gel electrophoresis (DIGE): a new strategy for identifying potential candidates in the pathogenesis of proliferative diabetic retinopathy.

AIMS/HYPOTHESIS: The aim of this study was to compare the protein profile of vitreous fluid from diabetic patients with proliferative diabetic retinopathy (PDR) with that from non-diabetic patients with idiopathic macular holes (MH). The mRNA of proteins differentially produced was also assessed in the retinas from diabetic and non-diabetic donors. MATERIALS AND METHODS: Vitreous humour from type 1 diabetic patients with PDR (n = 8) and from non-diabetic patients with MH (n = 10) closely matched in terms of age were studied. The comparative proteomic analysis was performed using fluorescence-based difference gel electrophoresis (DIGE). Differentially produced proteins (abundance ratio >1.4, p < 0.05) were identified by mass spectrometry. Expressions of mRNA were measured by real-time RT-PCR in retinas from ten human eyes obtained at post-mortem (five eyes from diabetic subjects and five eyes from non-diabetic subjects). RESULTS: Eight proteins were highly produced in PDR patients in comparison with non-diabetic subjects: zinc-alpha(2)-glycoprotein (ZAG), apolipoprotein (apo) A1, apoH, fibrinogen A, and the complement factors C3, C4b, C9 and factor B). We found three proteins that were underproduced in PDR subjects: pigment epithelial derived factor (PEDF), interstitial retinol-binding protein (IRBP) and inter-alpha-trypsin inhibitor heavy chain (ITIH2). There was no overlap in the vitreous levels of the above-mentioned proteins between PDR patients and non-diabetic control subjects. The differential production of ZAG, C3, factor B, PEDF and IRBP was further confirmed by western blot, and was in agreement with mRNA levels detected in the retina. CONCLUSIONS/INTERPRETATION: Proteomic analysis by DIGE, which permits an accurate quantitative comparison, was useful in identifying new potential candidates involved in the pathogenesis of PDR.

Anomalous costochondral cartilage in fetal anencephaly.

Anencephaly is a human fetal malformation with absence of brain and calvarium superior to the orbits. The consequent absence of hypothalamus provides a unique model for studying human development, and therefore skeletal growth, in the absence of hypothalamic hormones and their regulatory functions. To assess the influence of hypothalamic insufficiency on cartilage development, we studied costochondral cartilage sections from eight anencephalic fetuses (18-22 weeks old) and seven controls (16-22 weeks old) with pathologies not directly related to skeletal growth. We found a previously undescribed anomalous organization of the cartilage in the anencephalic. The proliferative chondrocytes showed a disordered appearance with an increased proliferative zonal length (156 +/- 28 microm in anencephalic fetuses vs. 103 +/- 14 microm in controls, p = 0.006) and a concomitant decrease in the maturing portion, where cells form ordered isogenic groups (58 +/- 13 microm in anencephalic fetuses vs. 93 +/- 19 microm in controls, p = 0.003). In addition, cell density was significantly decreased in the proliferating and maturing zones in the anencephalic cases (84 +/- 21 vs. 130 +/- 21 cells/40 microm(2) in proliferating zone; 53 +/- 8 vs. 94 +/- 8 in maturing portion, p < 0.005). These alterations in the developing cartilage of the anencephalic may contribute to the observed growth retardation in these fetuses and reflect modifications in pituitary hormones and growth factors resulting from reduction in hypothalamopituitary function.

Vascular endothelial growth factor is expressed in human fetal growth cartilage.

Angiogenesis is a crucial event in endochondral ossification. Chemoattractants and mitogens for endothelial cells (such as basic fibroblast growth factor [bFGF] and transforming growth factor beta [TGF-beta]), which act as local regulators of the process, are synthesized by chondrocytes under several stimuli and in relation to the differentiation stage of the cartilage. Vascular endothelial growth factor (VEGF) is a 44-kDa protein well known as a potent angiogenic molecule owing to its mitogenic and permeability-causing properties. In this work, VEGF was located by immunohistochemistry in growth plate cartilage of human fetuses (20-22 weeks old) and its expression was demonstrated by reverse-transcription polymerase chain reaction (RT-PCR). Primary culture of human fetal epiphyseal chondrocytes (HFEC) maintained VEGF expression at protein and messenger RNA (mRNA) levels and this expression was stimulated by cartilage-promoting growth factors incorporated into the culture media (rFGF-b, rTGF-beta1, and insulin-like growth factor [rFGF-b] at 50 ng/ml). The conditioned medium (CM) of HFEC stimulated the proliferation of endothelial cells, and this was partially blocked by anti-VEGF antibody. These studies showed VEGF production by chondrocytes of the epiphyseal growth cartilage and suggested a role of this factor in cartilage physiology and the angiogenic process.

Bcl-2 with loss of apoptosis allows accumulation of genetic alterations: a pathway to metastatic progression in human breast cancer.

We have examined whether the extended life span of cells induced by Bcl-2 in T(1) ductal breast carcinomas might favor the acquisition and accumulation of genetic alterations that induce lymph node metastases. We analyzed the expression of c-Myc, c-erbB-2 and epidermal growth factor receptor by immuno-histochemistry in a group of 142 T(1) (<2 cm) ductal breast carcinomas embedded in paraffin, previously studied for p53 mutation and Bcl-2 over-expression. We also measured the apoptotic status and estimated the excess risk (pOR) for lymph node metastasis according to the number of accumulated oncogene alterations and Bcl-2 and p53 expression. The linear relationship between number of oncogene alterations and presence of lymph node metastasis was statistically significant in Bcl-2-positive tumors (trend test, p = 0.03), p53-mutated tumors (trend test, p = 0.08) and tumors with loss of apoptosis (trend test, p = 0.08). Very large associations (pOR > 12) between the number of oncogene alterations and lymph node metastasis were observed among Bcl-2-positive tumors that showed increased loss of apoptosis (trend test, p = 0.03). Furthermore, in p53-negative tumors, a strong linear association was found between the number of oncogene alterations and risk of lymph node metastasis among Bcl-2-positive tumors (trend test, p = 0.03). In human T(1) ductal breast carcinoma, over-expression of Bcl-2 along with loss of apoptosis might render breast cancer cells susceptible to the acquisition of additional genetic lesions related to disease progression among p53-negative tumors. Thus, in breast cancer, there are at least 2 pathways to progression: Bcl-2- and p53-dependent mechanisms.

Genetic determinants of bone mass.

A genetic contribution to bone mass determination was first described in the early 70s. Elucidation of gene contribution to this has since been attempted through studies analyzing associations between bone mass acquisition and/or maintenance and polymorphic variations of several genes. The first to be described was the vitamin D receptor gene (VDR), initially claimed to contribute to almost 75% of the genetic variation in bone mineral density (BMD) in twin and general population studies. Not all of the studies published to date conclude that a clear relationship exists between polymorphic VDR alleles and BMD, and the molecular basis for the VDR gene polymorphisms influence on bone mineralization has not yet been clarified. Since then, other genes with a significant role in bone metabolism such as estradiol receptor, collagen type 1alpha1, TGF-beta1, interleukin-6, calcitonin receptor, alpha2-HS-glycoprotein, osteocalcin, calcium-sensing receptor, interleukin-1 receptor antagonist, beta3-adrenergic receptor, apolipoprotein E, PTH, IGF-I and glucocorticoid receptor have been analyzed. Some polymorphic variations in these genes have been associated in some works with significant differences in BMD, with even more significant contributions when associations of different gene polymorphisms were analyzed. Again, the molecular basis for the contribution of these alleles to bone mass determination has not yet been described. A different approach has been attempted by linkage analysis of loci involved in bone density in pedigrees with low BMD using BMD as a quantitative trait. Recent results do not confirm, in these families, any association with any of the previously reported genes, but rather with other as yet unidentified genes. The genetic contribution to mild variations in the general population, as a result of environmental and endogenous individual influences, probably differs completely from that providing a pathologic BMD.

Effects of TGF-beta1 on proliferation and IGFBP-3 production in a primary culture of human fetal epiphyseal chondrocytes (HFEC).

Proliferation and differentiation of chondrocytes from growth cartilage are modulated by hormones and growth factors, among which TGF-betas have been recognized as some of the more potent regulators although their specific cell effects on cartilage physiology are not fully understood. Primary human fetal epiphyseal chondrocytes (HEFC) constitutively produce TGF-beta1 at different times of culture progression. Treatment of 48-h. serum-deprived semiconfluent HFEC with 0.1-50 ng/ml of TGF-beta1 for 48-h. decreased (3H)Thymidine incorporation by 25-50 % and cell number by 25 %. In addition, IGFBP-3, the main insulin-like bonding protein produced by HFEC, showed a slight increase by TGF-beta1 in culture media. The changes in IGFBP-3 protein levels correlated well with its mRNA, indicating that TGF-beta1 is able to up-regulate IGFBP-3 synthesis in chondrocytes. Nevertheless, the IGFBP-3 accumulation in culture media does not produce a clear growth inhibitory effect on chondrocytes. Thus, we conclude that even though TGF-beta1 is able to up-regulate IGFBP-3, the growth inhibitory action produced by TGF-beta1 is not mediated by IGFBP-3 increase and appears to be mainly a direct TGF-beta1 effect on HFEC.