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INTRODUCTION: Craniocervical junction damages may result in a compression of the spinal cord. They may be caused by infectious, tumoral or inflammatory processes. Rheumatoid arthritis is probably among rheumatic diseases the most frequent cause of atlantoaxial arthritis. Nevertheless involvement of the craniocervical junction as the presenting symptom of rheumatoid arthritis is a very rare feature. EXEGESIS: We report the case of a 61 years old woman who presented with atlantoaxial involvement and spinal cord compression one year before the diagnosis of a seronegative rheumatoid arthritis. CONCLUSION: Symptomatic craniocervical junction damages may appear. Patients with damages of the craniocervical junction and negative investigations should be followed long-term; an underlying inflammatory disease may become evident after significant delay.  相似文献   
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Elderly patients with isolated systolic hypertension (ISH)--systolic blood pressure (SBP) > or =140 mmHg and diastolic blood pressure (DBP) <90 mmHg--have increased mortality and morbidity. The aim was to study the incidence of ISH in a younger population of between 15 and 60 years of age, and to measure pulse pressure (PP), mean arterial pressure (MAP) and heart rate (HR) in these subjects. The study population consisted of 27 783 subjects, aged 15-60 years, untreated for hypertension (HT) from a cohort of employees formed to study the incidence of HT in the French working population (AIHFP). BP and HR were measured with a validated, automatic device after 5, 6 and 7 min at rest. The prevalence of ISH was 6.9% in men, 2.3% in women. This prevalence was over 5% in young men and increased at 40-44 years; it was negligible in young women, but increased at 50-54 years to about 10% (ie to the same level as in men of the same age): PP in subjects with ISH (46.9 mmHg) was significantly higher than in the normotensive group (NT-40.9 mmHg); it was comparable in both young men (65.5 mmHg) and older men (66 mmHg); it was higher in men (63.1 mmHg) than in women (61.5 mmHg). HR was higher in ISH than in NT and it was higher in women ( approximately 5 bpm) in whom it decreased with age. The prevalence of ISH is not negligible in HT (30% men, 25% women), with a high prevalence in young subjects and elevated PP, MAP and HR values. These data should be taken into account as elevated ISH, PP and HR are considered as cardio-vascular risk factors.  相似文献   
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The heterogeneity of gamma-aminobutyric acid type A (GABA(A)) receptors contributes to the diversity of neuronal inhibition in the regulation of information processing. Although most GABA(A) receptors are located synaptically, the small population of alpha5GABA(A) receptors is largely expressed extrasynaptically. To clarify the role of the alpha5GABA(A) receptors in the control of behavior, a histidine-to-arginine point mutation was introduced in position 105 of the murine alpha5 subunit gene, which rendered the alpha5GABA(A) receptors diazepam-insensitive. Apart from an incomplete muscle relaxing effect, neither the sedative, anticonvulsant, nor anxiolytic-like activity of diazepam was impaired in alpha5(H105R) mice. However, in hippocampal pyramidal cells, the point mutation resulted in a selective reduction of alpha5GABA(A) receptors, which altered the drug-independent behavior. In line with the role of the hippocampus in certain forms of associative learning, trace fear conditioning, but not delay conditioning or contextual conditioning, was facilitated in the mutant mice. Trace fear conditioning differs from delay conditioning in that the conditioned and unconditioned stimulus are separated by a time interval. Thus, the largely extrasynaptic alpha5GABA(A) receptors in hippocampal pyramidal cells are implicated as control elements of the temporal association of threat cues in trace fear conditioning.  相似文献   
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Elevated whole-blood serotonin and decreased plasma melatonin (a circadian synchronizer hormone that derives from serotonin) have been reported independently in patients with autism spectrum disorders (ASDs). Here, we explored, in parallel, serotonin, melatonin and the intermediate N-acetylserotonin (NAS) in a large cohort of patients with ASD and their relatives. We then investigated the clinical correlates of these biochemical parameters. Whole-blood serotonin, platelet NAS and plasma melatonin were assessed in 278 patients with ASD, their 506 first-degree relatives (129 unaffected siblings, 199 mothers and 178 fathers) and 416 sex- and age-matched controls. We confirmed the previously reported hyperserotonemia in ASD (40% (35–46%) of patients), as well as the deficit in melatonin (51% (45–57%)), taking as a threshold the 95th or 5th percentile of the control group, respectively. In addition, this study reveals an increase of NAS (47% (41–54%) of patients) in platelets, pointing to a disruption of the serotonin-NAS–melatonin pathway in ASD. Biochemical impairments were also observed in the first-degree relatives of patients. A score combining impairments of serotonin, NAS and melatonin distinguished between patients and controls with a sensitivity of 80% and a specificity of 85%. In patients the melatonin deficit was only significantly associated with insomnia. Impairments of melatonin synthesis in ASD may be linked with decreased 14-3-3 proteins. Although ASDs are highly heterogeneous, disruption of the serotonin-NAS–melatonin pathway is a very frequent trait in patients and may represent a useful biomarker for a large subgroup of individuals with ASD.  相似文献   
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Immunotherapy by adoptive transfer of autologous tumour-infiltrating lymphocytes (TIL) shows promising clinical results for stage III (lymph nodes metastasis) melanoma patients, but some of them remain unresponsive. Here we analysed retrospectively the impact of resistance of melanoma cells to anti-proliferative cytokines on the clinical outcome of 24 TIL-treated metastatic melanoma patients. Patient relapse-free survival correlated significantly with Oncostatin M (OSM) and/or IL-6 sensitivity of melanoma cells, but not with interferon (IFN) gamma or tumour necrosis factor (TNF) alpha sensitivity. However, OSM/IL-6 sensitivity did not correlate with other known prognostic factors. Moreover, OSM and IL-6 were produced by TIL just before their injection to patients. In immunodeficient mice, OSM reduced human melanoma xenograft tumour growth, this effect being directly through inhibition of tumour cell proliferation rather than induction of apoptosis or necrosis. Thus, OSM/IL-6 resistance of melanoma cells appears to be a new escape mechanism to TIL treatment that could be added to the existing prognostic factors for early stage melanoma patients. This mechanism of action could be also relevant in other immunotherapy protocols, and could lead to better prognosis and anti-cancer treatments.  相似文献   
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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. RESULTS: HCG (1-50 IU/ml) increased LIF secretion by EEC cultures derived from follicular phase (up to 285+/-75%) or from secretory phase (up to 212+/-16%). In contrast, hCG reduced IL-6 secretion by EEC in both phases. The hCG/LH receptor gene was transcribed by EEC as evidenced by RT-PCR. Insulin-like growth factors 1 and 2 increased LIF secretion by EEC. Transforming growth factor beta1 stimulated LIF and reduced IL-6 secretion. CONCLUSIONS: Through hCG, the blastocyst may be involved in the control of its implantation (via an increase of proimplantatory LIF) and tolerance (via an inhibition of proinflammatory IL-6). Other growth factors present at the embryonic-endometrial interface are also involved in the control of LIF and IL-6 endometrial secretion.  相似文献   
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