995 resultados para sensitive nerve conduction velocity


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Velocity-density tests conducted in the laboratory involved small 4-inch diameter by 4.58-inch-long compacted soil cylinders made up of 3 differing soil types and for varying degrees of density and moisture content, the latter being varied well beyond optimum moisture values. Seventeen specimens were tested, 9 with velocity determinations made along two elements of the cylinder, 180 degrees apart, and 8 along three elements, 120 degrees apart. Seismic energy was developed by blows of a small tack hammer on a 5/8-inch diameter steel ball placed at the center of the top of the cylinder, with the detector placed successively at four points spaced 1/2-inch apart on the side of the specimen involving wave travel paths varying from 3.36 inches to 4.66 inches in length. Time intervals were measured using a model 217 micro-seismic timer in both laboratory and field measurements. Forty blows of the hammer were required for each velocity determination, which amounted to 80 blows on 9 laboratory specimens and 120 blows on the remaining 8 cylinders. Thirty-five field tests were made over the three selected soil types, all fine-grained, using a 2-foot seismic line with hammer-impact points at 6-inch intervals. The small tack hammer and 5/8-inch steel ball was, again, used to develop seismic wave energy. Generally, the densities obtained from the velocity measurements were lower than those measured in the conventional field testing. Conclusions were reached that: (1) the method does not appear to be usable for measurement of density of essentially fine-grained soils when the moisture content greatly exceeds the optimum for compaction, and (2) due to a gradual reduction in velocity upon aging, apparently because of gradual absorption of pore water into the expandable interlayer region of the clay, the seismic test should be conducted immediately after soil compaction to obtain a meaningful velocity value.

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Background:Type 2 diabetes (T2D) is associated with increased fracture risk but paradoxically greater BMD. TBS (trabecular bone score), a novel grey-level texture measurement extracted from DXA images, correlates with 3D parameters of bone micro-architecture. We evaluated the ability of lumbar spine (LS) TBS to account for the increased fracture risk in diabetes. Methods:29,407 women ≥50 years at the time of baseline hip and spine DXA were identified from a database containing all clinical BMD results for the Province of Manitoba, Canada. 2,356 of the women satisfied a well-validated definition for diabetes, the vast majority of whom (>90%) would have T2D. LS L14 TBS was derived for each spine DXA examination blinded to clinical parameters and outcomes. Health service records were assessed for incident non-traumatic major osteoporotic fracture codes (mean follow-up 4.7 years). Results:In linear regression adjusted for FRAX risk factors (age,BMI, glucocorticoids, prior major fracture, rheumatoid arthritis, COPD as a smoking proxy, alcohol abuse) and osteoporosis therapy, diabetes was associated with higher BMD for LS, femoral neck and total hip but lower LS TBS (all p<0.001). Similar results were seen after excluding obese subjects withBMI>30. In logistic regression (Figure), the adjusted odds ratio (OR) for a skeletal measurement in the lowest vs highest tertile was less than 1 for all BMD measurements but increased for LS TBS (adjusted OR 2.61, 95%CI 2.30-2.97). Major osteoporotic fractures were identified in 175 (7.4%) with and 1,493 (5.5%) without diabetes (p < 0.001). LS TBS predicted fractures in those with diabetes (adjusted HR 1.27, 95%CI 1.10-1.46) and without diabetes (HR 1.31, 95%CI 1.24-1.38). LS TBS was an independent predictor of fracture (p<0.05) when further adjusted for BMD (LS, femoral neck or total hip). The explanatory effect of diabetes in the fracture prediction model was greatly reduced when LS TBS was added to the model (indicating that TBS captured a large portion of the diabetes-associated risk), but was paradoxically increased from adding any of the BMD measurements. Conclusions:Lumbar spine TBS is sensitive to skeletal deterioration in postmenopausal women with diabetes, whereas BMD is paradoxically greater. LS TBS predicts osteoporotic fractures in those with diabetes, and captures a large portion of the diabetes-associated fracture risk. Combining LS TBS with BMD incrementally improves fracture prediction.

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OBJECTIVE: We examined the analytic validity of reported family history of hypertension and diabetes among siblings in the Seychelles. STUDY DESIGN AND SETTING: Four hundred four siblings from 73 families with at least two hypertensive persons were identified through a national hypertension register. Two gold standards were used prospectively. Sensitivity was the proportion of respondents who indicated the presence of disease in a sibling, given that the sibling reported to be affected (personal history gold standard) or was clinically affected (clinical status gold standard). Specificity was the proportion of respondents who reported an unaffected sibling, given that the sibling reported to be unaffected or was clinically unaffected. Respondents gave information on the disease status in their siblings in approximately two-thirds of instances. RESULTS: When sibling history could be obtained (n=348 for hypertension, n=404 for diabetes), the sensitivity and the specificity of the sibling history were, respectively, 90 and 55% for hypertension, and 61 and 98% for diabetes, using clinical status and, respectively, 89 and 78% for hypertension, and 53 and 98% for diabetes, using personal history. CONCLUSION: The sibling history, when available, is a useful screening test to detect hypertension, but it is less useful to detect diabetes.

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The physiological contribution of glucose in thermoregulation is not completely established nor whether this control may involve a regulation of the melanocortin pathway. Here, we assessed thermoregulation and leptin sensitivity of hypothalamic arcuate neurons in mice with inactivation of glucose transporter type 2 (Glut2)-dependent glucose sensing. Mice with inactivation of Glut2-dependent glucose sensors are cold intolerant and show increased susceptibility to food deprivation-induced torpor and abnormal hypothermic response to intracerebroventricular administration of 2-deoxy-d-glucose compared to control mice. This is associated with a defect in regulated expression of brown adipose tissue uncoupling protein I and iodothyronine deiodinase II and with a decreased leptin sensitivity of neuropeptide Y (NPY) and proopiomelanocortin (POMC) neurons, as observed during the unfed-to-refed transition or following i.p. leptin injection. Sites of central Glut-2 expression were identified by a genetic tagging approach and revealed that glucose-sensitive neurons were present in the lateral hypothalamus, the dorsal vagal complex, and the basal medulla but not in the arcuate nucleus. NPY and POMC neurons were, however, connected to nerve terminals from Glut2-expressing neurons. Thus, our data suggest that glucose controls thermoregulation and the leptin sensitivity of NPY and POMC neurons through activation of Glut2-dependent glucose-sensing neurons located outside of the arcuate nucleus.

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Metallic foreign bodies are rarely found in the maxillary sinus, and usually they have a dental origin.Potential complications related to foreign bodies include recurrent sinusitis, rhinolith formation, cutaneous fistula,chemical poisoning, facial neuralgic pain and even malignancies.Two main surgical approaches are currently used for the removal of foreign bodies in the maxillary sinus: the bone flap and the endoscopic sinus techniques. We are reporting two unusual cases of large high-velocity foreign bodies removed by a modified maxillary lateral antrotomy,with free bone flap repositioning and fixation with a titanium miniplate.

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We report on an 11-year-old female with a history of cervicobrachialgia and progressive weakness of the right arm. Cervical spine MRI showed an enhancing heterogeneous intradural mass occupying the right C6-C7 foramen. She underwent a right C6-C7 foraminotomy with a complete macroscopic removal of the lesion. Pathological examination revealed a synovial sarcoma. Treatment was completed by chemotherapy and proton radiotherapy, and the girl remained free of symptoms for 3 years. After appearance of new symptoms, a local recurrence was confirmed, and despite aggressive treatment with salvage chemotherapy and radiotherapy, the disease progressed beyond medical control, and the child died, 6 years after diagnosis. Early recognition of this rare entity compared to its more benign differential diagnosis is crucial, as an aggressive management is needed.

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This study aimed to compare foot plantar pressure distribution while jogging and running in highly trained adolescent runners. Eleven participants performed two constant-velocity running trials either at jogging (11.2 ± 0.9 km/h) or running (17.8 ± 1.4 km/h) pace on a treadmill. Contact area (CA in cm(2)), maximum force (F(max) in N), peak pressure (PP in kPa), contact time (CT in ms), and relative load (force time integral in each individual region divided by the force time integral for the total plantar foot surface, in %) were measured in nine regions of the right foot using an in-shoe plantar pressure device. Under the whole foot, CA, F(max) and PP were lower in jogging than in running (-1.2% [p<0.05], -12.3% [p<0.001] and -15.1% [p<0.01] respectively) whereas CT was higher (+20.1%; p<0.001). Interestingly, we found an increase in relative load under the medial and central forefoot regions while jogging (+6.7% and +3.7%, respectively; [p<0.05]), while the relative load under the lesser toes (-8.4%; p<0.05) was reduced. In order to prevent overloading of the metatarsals in adolescent runners, excessive mileage at jogging pace should be avoided.

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Allodynia (pain in response to normally non painful stimulation) and paresthesia (erroneous sensory experience) are two debilitating symptoms of neuropathic pain. These stem, at least partly, from profound changes in the non-nociceptive sensory pathway that comprises large myelinated neuronal afferents terminating in the gracile and cuneate nuclei. Further than neuronal changes, well admitted evidence indicates that glial cells (especially in the spinal cord) are key actors in neuropathic pain, in particular the possible alteration in astrocytic capacity to reuptake neurotransmitters (glutamate and GABA). Yet, the possibility of such a changed astrocytic scavenging capacity remains unexplored in the dorsal column pathway. The present study was therefore undertaken to assess whether peripheral nerve injury (spared nerve injury model, SNI) could trigger a glial reaction, and especially changes in glutamate and GABA transporters, in the gracile nucleus. SNI surgery was performed on male Sprague-Dawley rats. Seven days after surgery, rats were used for immunofluorescence (fixation and brain slicing), western-blot (fresh brain freezing and protein extraction) or GABA reuptake on synaptosomes. We found that SNI results in a profound glial reaction in the ipsilateral gracile nucleus. This reaction was characterized by an enhanced immunolabelling for microglial marker Iba1 as well as astrocytic protein GFAP (further confirmed by western-blot, p <0.05, n = 7). These changes were not observed in sham animals. Immunofluorescence and western-blot analysis shows that the GABA transporter GAT-1 is upregulated in the ipsilateral gracile nucleus (p <0.001; n = 7), with no detectable change in GAT-3 or glutamate transporters EAAT-1 and EAAT-2. Double immunoflurescence shows that GAT-1 and GFAP colocalize within the same cells. Furthermore, the upregulation of GFAP and GAT-1 were shown to occur all along the rostrocaudal axis of the gracile nucleus. Finally, synaptosomes from ipsilateral gracile nucleus show an increased capacity to reuptake GABA. Together, the data presented herein show that glial cells in the gracile nucleus react to neuropathic lesion, in particular through an upregulation of the GABA transporter GAT-1. Hence, this study points to role of an increased GABA transport in the dorsal column nuclei in neuropathic pain, calling attention to GAT-1 as a putative future pharmacological target to treat allodynia and paresthesia.

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This study examines cases of chronic drug users who died suddenly after drug administration. Victims were young subjects, aged from 19 to 35 from Switzerland and known to the police as long-term drug users. The circumstances of death suggested the occurrence of a sudden, unexpected death. Some victims were undergoing methadone treatment. In each case, a forensic autopsy and toxicological analyses were performed at the Institute of Forensic Medicine in Lausanne in Switzerland between 2002 and 2004, including hair analysis as a means to establish chronic drug use in general, and cocaine use in particular. The conduction system was examined histologically and cases showing potentially lethal changes were chosen for this report. The most frequent lesions found were severe thickening of the atrioventricular node artery, intranodal and perinodal fibrosis, and microscopic foci of chronic inflammatory infiltration. The authors conclude that pathological lesions in the conduction tissue may play a role in the occurrence of death attributed to intoxication consecutive to cocaine ingestion.

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SUMMARYAim: The embryonic/fetal heart is highly sensitive to oxygenation level and a transient uteroplacental hypoperfusion can lead to oxyradicals overproduction. Information about the molecular mechanisms underlying ischemia-reperfusion (I-R) injury in the developing heart is lacking. The Janus Kinase 2 / Signal Transducer and Activator of Transcription 3 (JAK2/STAT3) pathway, required for cardiogenesis and involved in protection of the adult heart against I-R, could also play a key role in the response of the fetal myocardium to transient oxygen deprivation. The aim of the study was to characterize the involvement of JAK2/STAT3 pathway and its interaction with other signalling pathways in the developing heart transiently submitted to anoxia. Furthermore, the response of the embryonic heart to an exogenous oxidant stress (H2O2) in comparison to reoxygenation-induced endogenous oxyradicals has been investigated.Methods: Hearts isolated from 4-day-old chick embryos were submitted to anoxia (30min) and reoxygenation (80min) with or without the antioxidant MPG, the JAK2/STAT3 inhibitor AG490 or exposed to H202 (50|iM-lmM). The time course of phosphorylation of STAT3atyr0Sine7 and Reperfusion Injury Salvage Kinase (RISK) proteins (PI3K, Akt, GSK3B, Glycogen Synthase and ERK2) was determined in homogenate" and in enriched nuclear and cytoplasmic fractions. The STAT3 DNA-binding was determined by EMSA and the expression of STAT3 specific target genes by RT-PCR. The chrono-, dromo- and inotropic disturbances were also investigated by ECG and mechanical recordings.Results: Phosphorylation of STATSaP (P-Tyr STAT3a) was increased by reoxygenation and reduced by MPG or AG490. STAT3 and GSK36 were detected both in nuclear and cytoplasmic fractions while PI3K, Akt, GS and ERK2 were restricted to cytoplasm. Reoxygenation led to nuclear accumulation of STAT3 but unexpectedly without DNA- binding. AG490 decreased the reoxygenation-induced phosphorylation of STABa^, Akt, GS and ERK2 and phosphorylation/inhibition of GSK3B in the nucleus, exclusively. Inhibition of JAK2/STAT3 delayed recovery of atrial rate, worsened RR. variability and prolonged arrhythmias compared to control hearts. Cardiac activity was altered only at concentrations >500μΜ of H2O2. Moreover, ImM of H2O2 suppressed atrial activity in 45% of the hearts, atrioventricular conduction in 66% and augmented P-Tyr STAT3awhich led to an increase in the DNA-binding but no change in the expression of three STAT3 specific target genes (iNOS, MnSOD, Cox-2).Conclusion: In the developing heart, besides its nuclear translocation without transcriptional activity, ROS-activated STAT3a can rapidly interact with RISK proteins present in nucleus and cytoplasm and reduce the anoxia-reoxygenation-induced arrhythmias. Moreover, the embryonic heart is highly resistant to H2O2 and the atrial region is the less affected. The role of JAK2/STAT3 in the response to reoxygenation-induced oxyradicals is different from the response to strong exogenous oxidant stress where STAT3 DNA-binding activity is increased. Such findings provide a first step in understanding the modulation of signalling cascades in the fetal heart submitted to transient intrauterine oxygen deprivation.RESUMEIntroduction: Le coeur embryonnaire et foetal est très sensible au manque d'oxygène et une hypoperfusion utéroplacentaire transitoire peut conduire à une surproduction d'espèces radicalaires (ROS). Dans le coeur en développement les mécanismes moléculaires impliqués en situation d'ischémie-reperfusion (I-R) ne sont pas connus. La voie de signalisation JAK2/STAT3 (Janus Kinase 2 / Signal Transducer and Activator of Transcription 3), impliquée aussi bien dans la cardiogenèse précoce que dans la protection du coeur adulte contre l'I-R, pourrait jouer un rôle clé dans la réponse du myocarde foetal à un déficit en oxygène. Cette étude a permis d'étudier le rôle de la voie JAK2/STAT3 et son interaction avec d'autres voies de signalisation dans un modèle de coeur embryonnaire soumis à un épisode anoxique. En outre, les effets du stress oxydant endogène provoqué par la réoxygénation ont été comparés à ceux du stress oxydatif exogène induit par du peroxyde d'hydrogène (H2O2).Méthodes: Des coeurs isolés d'embryons de poulet âgés de 4 jours ont été soumis à une anoxie (30min) suivie d'une réoxygénation (80min) en présence ou non de l'antioxydant MPG et de l'inhibiteur de JAK2/STAT3 AG490 ou exposés à de 1Ή202 (50μΜ-1πιΜ). L'évolution temporelle de la phosphorylation de 8ΤΑΤ3α*ΓΟδίη6705 (P-Tyr STAT3a) et celle de la phosphorylation des protéines de la voie RISK (Reperfusion Injury Salvage Kinase: PI3K, Akt, GSK3B, glycogène synthase GS et ERK2) ont été déterminés dans l'homogénat et dans les fractions nucléaire et cytopiasmique du myocarde. La liaison de STAT3 à l'ADN a été déterminée par EMSA et l'expression de gènes cibles de STAT3 (iNOS, MnSOD, Cox2) par RT-PCR. Les effets chrono-, dromo- et inotropes ont été déterminés par les enregistrements de l'ECG et de l'activité contractile ventriculaire.Résultats: STAT3 et GSK3B étaient présents dans les fractions nucléaire et cytopiasmique tandis que PI3K, Akt, GS et ERK2 n'étaient détectées que dans la fraction cytopiasmique. L'augmentation de P-Tyr STAT3a provoquée par la réoxygénation était significativement réduite par le MPG ou PAG490. La réoxygénation entraînait l'accumulation nucléaire de STAT3, mais étonnamment sans liaison avec l'ADN. A la réoxygénation TAG490 diminuait la phosphorylation d'Akt, GS et ERK2 ainsi que celle de GSK36 mais exclusivement dans la fraction nucléaire. L'inhibition de JAK2/STAT3 retardait également la récupération du rythme cardiaque et prolongeait la durée des arythmies. L'activité cardiaque n'était perturbée par de ΓΗ2Ο2 qu'à des concentrations >500μΜ. A ImM, ΓΗ2Ο2 supprimait l'activité auriculaire dans 45% des coeurs et la conduction auriculo-ventriculaire dans 66% et augmentait la formation de P-Tyr STAT3a et sa liaison à l'ADN sans modifier l'expression des gènes cibles.Conclusion: Les ROS produits par l'anoxie-réoxygénation activent STAT3a qui subit une translocation dans le noyau sans se lier à l'ADN et interagit rapidement avec des protéines de la voie RISK dans les compartiments nucléaire et cytopiasmique du coeur embryonnaire. Ce dernier, en particulier au niveau des oreillettes, se révèle très résistant au puissant stress oxydatif de l'H202 qui se différencie du stress lié à la réoxygénation en favorisant la liaison de STAT3 à l'ADN. Ces résultats originaux permettent une meilleure compréhension des mécanismes qui peuvent améliorer la récupération du coeur en développement après un épisode hypoxique intra-utérin.

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Posaconazole (POS) is a new antifungal agent for prevention and therapy of mycoses in immunocompromised patients. Variable POS pharmacokinetics after oral dosing may influence efficacy: a trough threshold of 0.5 ?g/ml has been recently proposed. Measurement of POS plasma concentrations by complex chromatographic techniques may thus contribute to optimize prevention and management of life-threatening infections. No microbiological analytical method is available. The objective of this study was to develop and validate a new simplified ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) method and a sensitive bioassay for quantification of POS over the clinical plasma concentration range. The UPLC-MS/MS equipment consisted of a triple quadrupole mass spectrometer, an electrospray ionization (ESI) source, and a C(18) analytical column. The Candida albicans POS-hypersusceptible mutant (MIC of 0.002 ?g/ml) ?cdr1 ?cdr2 ?flu ?mdr1 ?can constructed by targeted deletion of multidrug efflux transporters and calcineurin genes was used for the bioassay. POS was extracted from plasma by protein precipitation with acetonitrile-methanol (75%/25%, vol/vol). Reproducible standard curves were obtained over the range 0.014 to 12 (UPLC-MS/MS) and 0.028 to 12 ?g/ml (bioassay). Intra- and interrun accuracy levels were 106% ± 2% and 103% ± 4% for UPLC-MS/MS and 102% ± 8% and 104% ± 1% for bioassay, respectively. The intra- and interrun coefficients of variation were 7% ± 4% and 7% ± 3% for UPLC-MS/MS and 5% ± 3% and 4% ± 2% for bioassay, respectively. An excellent correlation between POS plasma concentrations measured by UPLC-MS/MS and bioassay was found (concordance, 0.96). In 26 hemato-oncological patients receiving oral POS, 27/69 (39%) trough plasma concentrations were lower than 0.5 ?g/ml. The UPLC-MS/MS method and sensitive bioassay offer alternative tools for accurate and precise quantification of the plasma concentrations in patients receiving oral posaconazole.