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There are few data on osteoporosis in men, but cross-sectional studies have shown that age-related bone loss in men is of lower magnitude than in women. To elucidate some controversies related partially to methodological aspects, we measured bone mineral density (BMD) by dual-energy X-ray absorptiometry (DEXA) at various skeletal sites (spine, hip, and whole body using a Hologic QDR-1500 device; forearm using an Osteometer DTX 100 device) in a large cohort of 1040 men, aged 19-85 years. The final investigation was performed on 934 men, aged 19-85 years, after exclusion of 106 men with disease or treatment known to affect bone metabolism. Peak BMD was achieved at 25 and 29 years at the lumbar spine and hip, respectively, but only at 40 and 37 years at the distal forearm and whole body, respectively. The magnitude of bone loss between peak bone mass and 80 years of age was linear at most sites and averaged 13%-18%; that is, SD of 1.1-1.8 from peak BMD, except for Ward's triangle, which showed a marked bone loss of 43% (i.e., 2.5 SD), and for the lumbar spine. In the entire cohort, increase of the average lumbar spine BMD after the age of 55 years was related to the development of osteoarthritis, because, in men without severe arthritis, lumbar spine BMD continued to decrease. Height-adjusted partial correlations indicate that both the mineral content and the area of long bones of the limbs increased with age up to 50 years, followed by a significant decrease of BMD without change of bone surface. SD of mean BMD increased significantly with age at most skeletal sites. In summary, age-related change of BMD varied according to skeletal site in men with peak bone mass achieved earlier at sites rich in trabecular bone than at those rich in cortical bone. Bone loss varied according to skeletal site from 14% to 43%. The variability of BMD increased with age, which may reflect interindividual variability of age-related bone loss.

Objective: In the present study, we investigated signal transduction pathways involved in TNF-alpha gene expression and TNF-alpha secretion by mast cells stimulated through the high affinity IgE receptor (FcepsilonRI)., Materials and Methods: TNF-alpha mRNA steady state levels and TNF-alpha secretion in the presence of specific pharmacological agents were monitored using rat basophilic leukemia cells (RBL-2H3) stimulated through FcepsilonRI. Relative amounts of TNF-alpha mRNA versus beta-actin levels were quantified by RNase protection and RT-PCR assays. TNF-alpha secretion was measured by a current ELISA test., Results: We show that EGTA (5 mM) prevented TNF-alpha mRNA expression and TNF-alpha secretion in antigen-stimulated cells. The protein kinase C (PKC) inhibitor bisindolylmaleimide I substantially blocked TNF-alpha secretion at 2 microM but had only a marginal effect on TNF-alpha mRNA expression. The results were similar when PKC isoforms were depleted by long-term exposure to 100 nM phorbol ester (PMA). The PI 3-kinase inhibitor wortmannin blocked TNF-alpha secretion at low doses (EC50= 13 nM), but only partially affected mRNA expression., Conclusions: Our results show that in FcepsilonRI-stimulated RBL-2H3 cells calcium mobilization, activation of PKC and PI 3-kinase are necessary for TNF-alpha secretion while for the increased TNF-alpha mRNA expression PKC activity is dispensable and PI 3-kinase activity only partially required.

Using rat basophilic leukemia (RBL-2H3) cells as a model, we investigated how aggregation of the high affinity receptor for IgE (Fc epsilonRI) regulates TNF-alpha gene expression. Antigenic stimulation of RBL-2H3 cells led to an increase in newly synthesized TNF-alpha mRNA that was dependent on continuous receptor aggregation and did not require de novo protein synthesis. Kinetic analysis showed that maximal levels were achieved at 60 min and waned by 180 min of stimulation. Concomitant with the transcriptional activation of the TNF-alpha gene, the rapid appearance and disappearance of a previously uncharacterized nuclear NF-kappaB DNA binding activity, comprised of two distinct protein complexes, were observed. These protein complexes bound to NF-kappaB sites within the TNF-alpha gene and contained novel proteins (three species of Mr between 90,000-110,000) distinct from the classical proteins in NF-kappaB complexes. The induced NF-kappaB binding activity required continuous receptor stimulation and induced NF-kappaB-dependent reporter gene expression. Consistent with a role for the novel NF-kappaB nuclear binding activity in TNF-alpha gene expression, deletion of several 5' kappaB elements in the TNF-alpha promoter abolished all measurable Fc epsilonRI-dependent induction of a reporter construct. Pharmacologic agents that inhibited the NF-kappaB binding activity also inhibited TNF-alpha mRNA expression. Our results demonstrate that a novel NF-kappaB-like nuclear binding activity plays an important role in regulation of the rapid and transient transcriptional activation of the TNF-alpha gene via Fc epsilonRI.

Vertebral deformities are a major complication of osteoporosis. Although their prevalence is known to increase with age, the absence of reference criteria complicates their radiologic diagnosis. We evaluated variations in the prevalence of vertebral deformities according to the diagnostic method used in 291 men and 262 women older than 50 years included in the European Vertebral Osteoporosis Study. Lateral radiographs of the thoracic and lumbar spine were obtained in all subjects using standardized parameters. Six morphometric and quantitative methods were used to detect vertebral deformities. The prevalence of vertebral deformities, the number of vertebral deformities per 100 subjects and the prevalence of deformities for each vertebra varied according to the method used. With most methods, the percentage of subjects with vertebral deformities and the number of vertebral deformities were similar among the men and among the women. In the women, the prevalence and the number of vertebral deformities increased with age; beyond 70 years of age, however, the prevalence remained stable with advancing age, although the number of deformities per patient increased. In men, the prevalence of vertebral deformities remained stable with advancing age, suggesting that osteoporosis was not the only cause of vertebral deformity in this group. In conclusion, the prevalence of vertebral deformities varies according to the diagnostic method used. In men, none of the six methods evaluated in this study adequately differentiates osteoporotic deformities from deformities due to other causes.

Clinically apparent vertebral deformities are associated with reduced survival. The majority of subjects with radiographic vertebral deformity do not, however, come to medical attention. The aim of this study was to determine the association between radiographic vertebral deformity and subsequent mortality. The subjects who took part in the analysis were recruited for participation in a multicentre population-based survey of vertebral osteoporosis in Europe. Men and women aged 50 years and over were invited to attend for an interviewer-administered questionnaire and lateral spinal radiographs. Radiographs were evaluated morphometrically and vertebral deformity defined according to established criteria. The participants have been followed by annual postal questionnaire--the European Prospective Osteoporosis Study (EPOS). Information concerning the vital status of participants was available from 6480 subjects, aged 50-79 years, from 14 of the participating centres. One hundred and eighty-nine deaths (56 women and 133 men) occurred during a total of 14,380 person-years of follow-up (median 2.3 years). In women, after age adjustment, there was a modest excess mortality in those with, compared with those without, vertebral deformity: rate ratio (RR) = 1.9 (95% confidence interval (CI) 1.0,3.4). In men, the excess risk was smaller and non-significant RR = 1.3 (95% CI 0.9,2.0). After further adjusting for smoking, alcohol consumption, previous hip fracture, general health, body mass index and steroid use, the excess risk was reduced and non-significant in both sexes: women, RR = 1.6 (95% CI 0.9,3.0); men RR = 1.2 (95% CI 0.7,1.8). Radiographic vertebral deformity is associated with a modest excess mortality, particularly in women. Part of this excess can be explained by an association with other adverse health and lifestyle factors linked to mortality.

Facial nerve intraparotid neuromas are rare. We report two cases with no facial paralysis. In the first case, the clinical protocol for the evaluation of a parotid mass did not suggest the intramastoid tumor extension. This extension was shown by CT and MRI and confirmed by gross and microscopic appearance. In the second case, no intrapretrous extension was observed with MRI. The diagnosis of neuroma was made during surgery. With a literature review, we discuss the diagnostic difficulties encountered in the investigation of parotid facial nerve tumors, emphasizing on the usefulness of CT and MRI in its diagnosis.

A 37-year-old man developed excessive daytime sleepiness, sleep attacks and cataplexy revealing an hypothalamic tumour. Multiple Sleep Latency Tests (MSLT) were characteristics of narcolepsy. Tissue typing was positive for HLA DR2 and DQ1. Most cases of narcolepsy are idiopathic without any evidence of brain pathology. Although symptomatic narcolepsy may occur occasionally with diencephalic lesions. The relationship between narcolepsy with diencephalic lesions is unsettled and will be discussed.

Puerperal laparoscopic sterilization was performed in 732 women under anaesthesia at the Maternity of Noumea (New-Caledonia). There were no complications. Among the per-operative and postoperative incidents which occurred, there were 0.8% pregnancies, 3.6% bleeding of the broad ligament which was controlled during laparoscopy and 3% events (adhesion, pain) which required general anaesthesia. It was concluded that the described technique of puerperal laparoscopic sterilization is a safe, simple, rapid, inexpensive and reliable surgical technique in expert hands.

A way of evaluating the part played by non-drug treatments is to study cases of patients who discontinued stimulant medications but still came back for follow-up visits. Out of 40 patients with narcolepsy-cataplexy, three refused medication because their work was compatible with a regimen of naps (follow-up 1 year), and 10 stopped taking drugs when they could adapt nap therapy to a new life-style (follow-up 6.9 +/- 5 years). Three interrelated levels of non-pharmacological treatments of narcolepsy were examined: 1) Behavioral management, which includes: (A) structured sleep schedules: literature shows that a single long afternoon nap proffered greatest performance benefits in reaction time, significantly increased over a no-nap control condition, with no evidence of sleep inertia. The placement of this nap might yield better results if scheduled 1 hour before that of a normal subject. (B) Dietary factors: little is known about the effects of diet in narcoleptics; however, avoiding simple sugars will improve alertness in some patients. 2) Medical and psychiatric aspects of care. 3) Social factors as an interface between the patients and their environment.

The effect of the H1-antihistamine drug loratadine and its active metabolite descarboxyethoxyloratadine upon histamine release was examined on anti-immunoglobulin E (IgE) triggered human basophils and 2,4-dinitrophenyl (DNP) triggered rat basophilic leukemia (RBL-2H3) cells. In both experimental systems, dose-dependent inhibition of histamine release was observed at descarboxyethoxyloratadine and loratadine doses above 2 and 7 microM, respectively. In the RBL-2H3 experimental system, inhibition by loratadine increased when the concentration of extracellular Ca2+ was reduced from 1.8 to 0.45 mM. We further investigated the effect of loratadine and descarboxyethoxyloratadine on the increase in cytosolic calcium concentration (Ca2+)i, an early step in biochemical events leading to exocytosis. The effect of these two drugs upon (Ca2+)i changes was measured using the fluorescent probe fura-2 loaded into RBL-2H3 cells passively sensitized with DNP-specific IgE. Both drugs inhibited, in a dose-dependent manner (2.5-25 microM), the (Ca2+)i rise induced by DNP-BSA challenge in sensitized RBL cells, a process observed in both the presence and absence of extracellular Ca2+. Loratadine also inhibited the Mn2+ influx into these cells, thus reflecting the Ca2+ influx. These results suggest that loratadine and descarboxyethoxyloratadine impair the increase in (Ca2+)i following cell activation by decreasing both the influx of extracellular Ca2+ and the release of Ca2+ from intracellular stores.

A new immunoassay (ELISA) based on an antiserum that preferentially recognizes the free form of the pyridinoline (Pyr) crosslink was used to assess the urinary excretion of Pyr in a large normal sample of the population comprising 236 men and 193 women 30-90 years of age. Urinary Pyr increased significantly with age in both sexes. In women Pyr was higher than in men (57 +/- 21 versus 46 +/- 17 nmol/mmol creatinine, p < 0.001), and the menopause was reflected by a mean 37% increase, from an average 43 to 59 nmol/mm creatinine (p < 0.001). In 52 patients with active Paget's disease of bone, Pyr excretion was markedly increased (206 +/- 160 nmol/mmol creatinine, p < 0.001 versus controls) and decreased by 71% after 3 days of IV treatment with the bisphosphonate pamidronate. Free Pyr measured by the ELISA and the total urinary excretion measured by HPLC were highly correlated both in normals (n = 74, r = 0.83, p < 0.001) and in Pagetic patients (n = 20, r = 0.93, p < 0.001). The mean intra- and interassay coefficients of variation of the ELISA were below 9 and 15%, respectively. It is concluded that this new convenient immunoassay of Pyr should be valuable for the clinical investigation of patients with osteoporosis and other metabolic bone diseases.

The actual dilemma in studying the binding and triggering capacity of IgE from allergic patients is the lack of cultured basophils or mast cell analogs of human origin. Human IgE binds with exquisite species specificity to the high affinity IgE receptor (Fc epsilon RI) expressed on the surface of these cells. In rodents this receptor has been characterized as a tetrameric plasma membrane protein composed of an IgE-binding alpha chain, a beta chain and two disulfide-linked gamma chains. In order to establish a cell line expressing the alpha chain of human Fc epsilon RI which can be triggered with IgE from human patients and specific allergen, we transfected the cDNA coding for the human alpha subunit into rat basophilic leukemia cells. The resulting transfectants express the human alpha chain on the cell surface in the form of a hybrid complex associated with endogenous rat gamma chains. After sensitization with human IgE from mite-specific patients, the transfectant produces a calcium response upon incubation with allergen. The established cell line can be used as a model system to study the mechanism of mast cell triggering through IgE from allergic patients.

The antigenic and allergenic structure of Der f I, a major allergen of the house dust mite Dermatophagoides farinae (Df) was investigated by means of a panel of 11 selected monoclonal antibodies (mAb) obtained from BALB/c mice immunized with purified Der f I. The species specificity of these mAb, tested with Der f I and Der p I--the homologous allergen from Dermatophagoides pteronyssinus--was generally restricted to Der f I since 10 out of 11 mAb reacted only with this allergen. Epitope specificity of the mAb was determined by both competitive inhibition and sandwich ELISA experiments. The results indicated the presence of at least four non-overlapping, non-repeated antigenic sites on Der f I, which were recognized by one or several mAb (sites A, B, C and D). Comparative epitope specificity studies between human IgE antibodies and mice mAb were performed, on sera and basophils of Df sensitive patients, using different inhibition assays (ELISA and histamine release experiments). The degree of inhibition varied between the patients and upon the assay design. Most of the mAb tested were found to significantly inhibit the binding of human IgE to Der f I (p less than 0.01) when compared with Der p I specific mAb as a control. The mAb reacting with site A was found to be the most potent inhibitor, presenting a mean inhibition of up to 56% in ELISA as well as in histamine release experiments. The results show that both human IgE antibodies and mAb can be directed against identical or closely related epitopes of Der f I. Therefore anti-Der f I mAb constitute immunologic probes in further allergenic epitope and peptide analysis of this major mite allergen.

Histamine release experiments were performed over a 10(6)-fold range of allergen concentrations on basophils of patients sensitive to Dermatophagoides farinae. Two extracts of D. farinae were used, a partially purified one (Df 80d) containing several allergens and a highly purified component (Ag11). This histamine release patterns obtained with the complex allergen mixture Df 80d gave broad histamine release curves presenting an initial increase, followed by a decrease or a plateau, with occasionally a small dip. The Ag11-induced histamine release curves presented two peaks (bimodal pattern), separated by a more or less pronounced inhibition dip. No non-specific histamine releasing activity was observed with the basophils of two controls. The possible theoretical models for the bimodal histamine release patterns are discussed.

Two new cases of paracentric inversion are reported. One involved the short arm of chromosome 1 and affected two generations and the other involved the long arm of chromosome 5 and was described in 5 generations. The relationships between paracentric inversions and reproductive problems are discussed in the light of the literature.

Sedimentation at unit gravity of human bone marrow, during 15 hours at 4 degrees C on a linear density gradient of Ficoll in culture medium ranging from 1.020 to 1.065 g/ml shows that it exists a differential migration of bone marrow cells subpopulation with a precise mean densities : we find successively : 1.021 +/- 1.10(-3) g/ml for the lymphocytes, 1.024 +/- 2.5.10(-3) g/ml for the non eosinophil granulocytes, 1.025 +/- 2.5.10(-3) g/ml for the metamyelocytes, 1.030 +/- 3.5.10(-3) g/ml for the immature myeloid cells (myeloblasts, promyelocytes, myelocytes), 1.040 +/- 3.10(-3) g/ml for the eosinophil granulocytes, 1.055 +/- 10.10(-3) g/l for the megakaryocytes. The highest percentages of S phase cells, G2 and M phase cells determinated with a cytofluorograph correspond to peaks of immature myeloid cells (myeloblasts, promyelocytes and myelocytes). This method of bone marrow cells separation may be used to study the cell cycle in pathological bone marrows (leukaemia in particular) and to determine the effects and the efficiency of some antimitotics.

Two observations of paracentric inversion in man are reported. One is located on the long arm of chromosome 1 and was observed over two generations. The other is on the long arm of chromosome 5 and was transmitted over three generations. The possible implications of paracentric inversions on the phenotype and fertility are discussed.

Sedimentation at unit gravity of human bone marrow cells, for 15 h at 4 degrees C on linear density gradient of Ficoll in culture medium ranging from 1.020 to 1.065 g/ml shows that a differential migration of the bone marrow cell sub-populations exists with precise mean densities 1.021 +/- 1 x 10(-3) g/ml for lymphocytes; 1.024 +/- 2.5 x 10(-3) g/ml for non-eosinophil granulocytes; and 1.055 +/- 10 x 10(-3) g/ml for metamyelocytes; 1.030 x 3.5 x 10(-3) g/ml for other myeloid cells (myeloblasts, promyelocytes, myelocytes); 1.040 +/- 1.040 +/- 3 x 10(-3) g/ml for eosinophil granulocytes; and 1.055 +/- 10 x 10(-3) g/ml for megakaryocytes. The highest percentages of S phase cell and G2 and M phase cells determined by a cytofluorograph correspond to the peaks of immature myeloid cells (myeloblasts, promyelocytes and myelocytes). This method of bone marrow cell separation may be used to study the cell cycle in pathological bone marrows (leukaemia in particular) and to determine the effects and the efficiency of some antimitotics.