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1.
Osteoarthritis Cartilage ; 28(2): 231-238, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31682906

RESUMEN

OBJECTIVE: To evaluate infrared (IR) spectroscopy of serum as a screening tool to differentiate dogs affected by naturally occurring osteoarthritis (OA) associated with cranial cruciate ligament rupture (CrCLR) and controls. METHOD: 104 adult dogs with CrCLR (affected group) and 50 adult control dogs were recruited for this prospective observational study. Serum samples were collected preoperatively from CrCLR dogs and from a subset of these dogs at 4-, and 12-week post-surgical intervention to stabilize the affected stifles. Serum was collected once from control dogs. Dry films were made from serum samples, and IR absorbance spectra acquired. Data preprocessing, principal component analysis and multivariate analysis of covariance were performed to separate samples from the two groups, and to evaluate temporal differences. Weighted logistic regression with L1 regularization method was used to develop a predictive model. Model performance based on an independent test set was evaluated. RESULTS: Spectral data analysis revealed significant separation between the sera of CrCLR and control dogs (P < 0.0001), but not amongst different time points in the OA group. The sensitivity, specificity, AUC and accuracy of the test set were 84.62%, 96.15%, 93.20% and 92.31% respectively. CONCLUSIONS: These findings confirm the potential of IR-spectroscopy of serum with chemometrics methods to differentiate controls from dogs with OA associated with CrCLR. This is the first step in development of an economic, and comparatively simple IR-based screening serum test for OA. Utility of this tool as a clinical screening and diagnostic test requires further investigation and validation.


Asunto(s)
Lesiones del Ligamento Cruzado Anterior/veterinaria , Enfermedades de los Perros/sangre , Osteoartritis/veterinaria , Animales , Ligamento Cruzado Anterior/cirugía , Lesiones del Ligamento Cruzado Anterior/sangre , Lesiones del Ligamento Cruzado Anterior/diagnóstico , Lesiones del Ligamento Cruzado Anterior/cirugía , Estudios de Casos y Controles , Perros , Tamizaje Masivo , Osteoartritis/sangre , Osteoartritis/diagnóstico , Osteoartritis/cirugía , Espectroscopía Infrarroja por Transformada de Fourier , Rodilla de Cuadrúpedos/lesiones , Rodilla de Cuadrúpedos/cirugía
2.
Diagn Interv Imaging ; 99(9): 519-524, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29934239

RESUMEN

PURPOSE: To identify the effects of shear wave elastography in the fetus for evaluation in widespread use. MATERIALS AND METHODS: The Health Risk Assessment method proposed by the National Research Council was used with literature to evaluate the safety of shear wave elastography for the fetus regarding its potential effects in human tissues. RESULTS: The experimental and epidemiologic data from 25 articles showed that shear wave elastography maintained the same thermal effect as pulsed Doppler ultrasound already authorized in obstetrics, and that cavitation effect on fetal tissue is improbable. Nonetheless, the vibratory character of shear waves could induce displacement of fetal tissue while potential effects of very short duration energy peaks of the radiation force focused wave front remain unknown. CONCLUSION: The actual knowledge does not provide enough information to assess the effects of shear wave elastography on fetal tissues, thus these points have to be explored by further experimental studies.


Asunto(s)
Diagnóstico por Imagen de Elasticidad , Feto/diagnóstico por imagen , Medición de Riesgo , Animales , Femenino , Humanos , Embarazo , Ultrasonografía Doppler , Ultrasonografía Prenatal
3.
J Gynecol Obstet Hum Reprod ; 46(2): 167-173, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28403974

RESUMEN

OBJECTIVES: (i) To identify the proportion of non-pregnant women intending to use self-medication and self-administered alternative products (dietary supplements, essential oils and herbal teas) in the event of pregnancy, and the proportion of pregnant women using these products. (ii) To describe women's risk perception related to these products and the advice given by health professionals. METHODS: A cross-sectional study was conducted. One hundred and twenty-eight women (60 non-pregnant and 68 pregnant women) responded to a self-administered questionnaire. RESULTS: The proportion of pregnant women using self-medication was higher than the proportion of non-pregnant women intending to use self-medication (72% vs 48%, P=0.01) and lower for the use of herbal teas (29% vs 63%, P<0.01). There were no differences between the two groups for dietary supplements (25%) and essential oils (18%). Non-prescribed medications were perceived as a risk by 90% of all the women. Dietary supplements were considered as a medication by 68% of pregnant women and 48% of non-pregnant women (P=0.04). Health professionals provided advice for alternative products to 23% of the pregnant women, and 83% of the non-pregnant women expressed the wish to receive advice if they became pregnant. CONCLUSION: Health professionals should inform women, even before pregnancy, about the safe use of medications and alternative products during pregnancy.


Asunto(s)
Terapias Complementarias/estadística & datos numéricos , Abuso de Medicamentos/estadística & datos numéricos , Medicamentos sin Prescripción/uso terapéutico , Complicaciones del Embarazo/tratamiento farmacológico , Complicaciones del Embarazo/epidemiología , Automedicación/estadística & datos numéricos , Adolescente , Adulto , Terapias Complementarias/efectos adversos , Terapias Complementarias/métodos , Estudios Transversales , Suplementos Dietéticos/efectos adversos , Suplementos Dietéticos/estadística & datos numéricos , Abuso de Medicamentos/efectos adversos , Femenino , Francia/epidemiología , Conocimientos, Actitudes y Práctica en Salud , Conductas de Riesgo para la Salud , Humanos , Persona de Mediana Edad , Aceites Volátiles/efectos adversos , Aceites Volátiles/uso terapéutico , Percepción , Embarazo , Mujeres Embarazadas/psicología , Automedicación/efectos adversos , Encuestas y Cuestionarios , Tés de Hierbas/efectos adversos , Tés de Hierbas/estadística & datos numéricos , Adulto Joven
4.
J Virol ; 91(4)2017 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-27928016

RESUMEN

The persistence of latently HIV-infected cells in patients under combined antiretroviral treatment (cART) remains the major hurdle for HIV eradication. Thus far, individual compounds have not been sufficiently potent to reactivate latent virus and guarantee its elimination in vivo. Thus, we hypothesized that transcriptional enhancers, in concert with compounds triggering the innate immune system, are more efficient in reversing latency by creating a Th1 supportive milieu that acts against latently HIV-infected cells at various levels. To test our hypothesis, we screened six compounds on a coculture of latently infected cells (J-lat) and monocyte-derived dendritic cells (MDDCs). The protein kinase C (PKC) agonist prostratin, with a Toll-like receptor 8 (TLR8) agonist, resulted in greater reversion of HIV latency than any single compound. This combinatorial approach led to a drastic phenotypic and functional maturation of the MDDCs. Tumor necrosis factor (TNF) and cell-cell interactions were crucial for the greater reversion observed. Similarly, we found a greater potency of the combination of prostratin and TLR8 agonist in reversing HIV latency when applying it to primary cells of HIV-infected patients. Thus, we demonstrate here the synergistic interplay between TLR8-matured MDDCs and compounds acting directly on latently HIV-infected cells, targeting different mechanisms of latency, by triggering various signaling pathways. Moreover, TLR8 triggering may reverse exhaustion of HIV-specific cytotoxic T lymphocytes that might be essential for killing or constraining the latently infected cells. IMPORTANCE: Curing HIV is the Holy Grail. The so-called "shock and kill" strategy relies on drug-mediated reversion of HIV latency and the subsequent death of those cells under combined antiretroviral treatment. So far, no compound achieves efficient reversal of latency or eliminates this latent reservoir. The compounds may not target all of the latency mechanisms in all latently infected cells. Moreover, HIV-associated exhaustion of the immune system hinders the efficient elimination of the reactivated cells. In this study, we demonstrated synergistic latency reversion by combining agonists for protein kinase C and Toll-like receptor 8 in a coculture of latently infected cells with myeloid dendritic cells. The drug prostratin stimulates directly the transcriptional machinery of latently infected cells, and the TLR8 agonist acts indirectly by maturing dendritic cells. These findings highlight the importance of the immune system and its activation, in combination with direct-acting compounds, to reverse latency.


Asunto(s)
VIH-1/efectos de los fármacos , VIH-1/fisiología , Ésteres del Forbol/farmacología , Receptor Toll-Like 8/agonistas , Activación Viral/efectos de los fármacos , Adulto , Animales , Recuento de Linfocito CD4 , Comunicación Celular , Línea Celular , Técnicas de Cocultivo , Relación Dosis-Respuesta a Droga , Sinergismo Farmacológico , Femenino , Infecciones por VIH/inmunología , Infecciones por VIH/metabolismo , Infecciones por VIH/virología , Humanos , Masculino , Persona de Mediana Edad , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Proteína Quinasa C beta/metabolismo , Quinasa Syk/metabolismo , Subgrupos de Linfocitos T/metabolismo , Subgrupos de Linfocitos T/virología , Factor de Necrosis Tumoral alfa/metabolismo , Carga Viral , Latencia del Virus
5.
Rev Med Suisse ; 11(458): 181-6, 2015 Jan 21.
Artículo en Francés | MEDLINE | ID: mdl-25831610

RESUMEN

The year 2014 was rich in significant advances in all areas of internal medicine. Many of them have an impact on our daily practice and on the way we manage one problem or another. From the use of the ultrasound for the diagnosis of pneumonia to the choice of the site of venous access and the type of line, and the increasing complexity of choosing an oral anticoagulant agent, this selection offers to the readers a brief overview of the major advances. The chief residents in the Service of internal medicine of the Lausanne University hospital are pleased to share their readings.


Asunto(s)
Medicina Interna/tendencias , Cuerpo Médico de Hospitales , Enfermedad de Alzheimer/tratamiento farmacológico , Antiinflamatorios no Esteroideos/uso terapéutico , Anticoagulantes/uso terapéutico , Presión Arterial/fisiología , Cateterismo Venoso Central , Diverticulitis/terapia , Servicio de Urgencia en Hospital , Hospitales Universitarios , Humanos , Hipertensión/cirugía , Fibrosis Pulmonar Idiopática/tratamiento farmacológico , Riñón/inervación , Neumonía/diagnóstico por imagen , Embolia Pulmonar/diagnóstico , Piridonas/uso terapéutico , Choque Séptico/terapia , Simpatectomía/métodos , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores , Ultrasonografía , Tromboembolia Venosa/tratamiento farmacológico , Deficiencia de Vitamina B 12/etiología , Vitamina E/uso terapéutico
6.
Vet Comp Orthop Traumatol ; 27(4): 249-56, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24992079

RESUMEN

OBJECTIVES: The effects of insertion speed in revolutions per minute (RPM) and pilot hole predrilling for placement of threaded external skeletal fixation pins on temperature and morphological damage in cortical bone were evaluated. The null hypothesis states that insertion speed and predrilling will have no significant effect on temperature and morphological damage. METHODS: Fixation pins were inserted into cadaveric canine femurs at speeds of 700 RPM and 150 RPM, with and without pre-drilling. Temperature was measured at each cortex 0.5 mm and 3.0 mm from each insertion site. Samples were examined grossly and by scanning electron microscopy for evidence of morphological damage. Data were analysed for maximum temperature, temperature increase, sites above thermal necrosis thresholds, microcracks, thread quality and gross damage. RESULTS: Predrilling had a significant effect on maximum temperature, temperature increase, sites exceeding necrosis thresholds, microcracks, thread quality and gross damage. Speed of insertion had no significant effect on any of the measured parameters following predrilling, but had a significant effect on thread quality without predrilling. CLINICAL SIGNIFICANCE: Our results fail to reject the null hypothesis concerning insertion speed, which had no significant effect on thermal damage, and minimal effect on morphological damage, which was negated by predrilling. Our results reject the null hypothesis concerning predrilling and support the practice of predrilling fixation pin insertion sites.


Asunto(s)
Clavos Ortopédicos/veterinaria , Huesos/fisiología , Perros , Fijadores Externos/veterinaria , Animales , Fenómenos Biomecánicos , Cadáver
7.
Osteoporos Int ; 25(11): 2617-23, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25027111

RESUMEN

UNLABELLED: Bone density measurements are important for evaluation and follow-up of children with alterations in their mineral status (increased risk for fractures and osteoporosis subsequently). Interpretation of these measurements relies on the availability of appropriate reference equations. We developed gender-specific, age-dependent reference values of bone density for Central European children. INTRODUCTION: In recent years, there has been an increasing demand for the measurement of bone density in children exposed to an increased risk of early alterations in their bone status. These values must be compared to an adequate reference population. The aim of the present study was to create reference equations of radial speed of sound (SOS) for Central European children and adolescents. METHODS: In this cross-sectional study, SOS values were measured at the distal third of the radius in 581 Swiss children and adolescents (321 girls and 260 boys) aged 6 to 16 years using the Sunlight Omnisense® 7000P quantitative ultrasound system. RESULTS: Gender-specific reference equations for SOS values were derived by polynomial regression and combined a cubic dependence of age and a linear dependence of height. The fitted SOS curves in our study population show a plateau period in both genders for younger ages followed by an increase phase beginning at the age of 12 in girls and 14 in boys. Neither the reported level of physical activity nor additional sport nor self-reported calcium intake influenced the reference equations. CONCLUSIONS: Our results show a good agreement with similar studies using the same measurement technique on other body parts, suggesting a wide applicability of the obtained reference curves over different European populations.


Asunto(s)
Densidad Ósea/fisiología , Radio (Anatomía)/fisiología , Adolescente , Envejecimiento/fisiología , Niño , Estudios Transversales , Femenino , Humanos , Masculino , Radio (Anatomía)/diagnóstico por imagen , Valores de Referencia , Caracteres Sexuales , Ultrasonografía
8.
Opt Express ; 22(6): 7014-27, 2014 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-24664050

RESUMEN

Intermittent scanning for continuous-wave quantum cascade lasers is proposed along with a custom-built laser driver optimized for such operation. This approach lowers the overall heat dissipation of the laser by dropping its drive current to zero between individual scans and holding a longer pause between scans. This allows packaging cw-QCLs in TO­3 housings with built-in collimating optics, thus reducing cost and footprint of the device. The fully integrated, largely analog, yet flexible laser driver eliminates the need for any external electronics for current modulation, lowers the demands on power supply performance, and allows shaping of the tuning current in a wide range. Optimized ramp shape selection leads to large and nearly linear frequency tuning (>1.5 cm−1). Experimental characterization of the proposed scheme with a QCL emitting at 7.7 µm gave a frequency stability of 3.2×10−5 cm−1 for the laser emission, while a temperature dependence of 2.3×10−4 cm−1/K was observed when the driver electronics was exposed to sudden temperature changes. We show that these characteristics make the driver suitable for high precision trace gas measurements by analyzing methane absorption lines in the respective spectral region.

9.
Rev Med Suisse ; 9(370): 199-202, 2013 Jan 23.
Artículo en Francés | MEDLINE | ID: mdl-23413650

RESUMEN

The knowledge in internal medicine is constantly and so rapidly evolving that practices have to be updated and adjusted to recent scientific rules, in order to improve quality and efficiency in the day to day activities. Residents in the Service of internal medicine of the Lausanne University present several relevant papers published in 2012, whose results are susceptible to change the daily hospital practices. From modest impacts to real revolution, a variety of subjects are discussed in the perspective of evidence based medicine.


Asunto(s)
Enfermedades Cardiovasculares/terapia , Enfermedades Pulmonares/terapia , Enfermedades Cardiovasculares/diagnóstico , Vías Clínicas , Humanos , Medicina Interna , Pielonefritis/tratamiento farmacológico , Sepsis/terapia , Estado Epiléptico/tratamiento farmacológico , Accidente Cerebrovascular/prevención & control
10.
Rev Med Suisse ; 8(360): 2072-4, 2076-7, 2012 Oct 31.
Artículo en Francés | MEDLINE | ID: mdl-23185929

RESUMEN

In general practice, vitamin B12 levels are measured when searching an origin for an anemic status (usually megaloblastic anemia), for various neurological disorders (usually polyneuropathy) or for neurocognitive disorders. Although the pathologies associated with vitamin B12 deficiency are well known, hypervitaminemic B12 status is often fortuitous and frequent finding. The aim of this article is to present the disease entities associated with hypervitaminemia B12, the clinical implications of this dysvitaminosis and a practical approach when this laboratory abnormality is found.


Asunto(s)
Vitamina B 12/sangre , Algoritmos , Enfermedades Autoinmunes/sangre , Enfermedades Autoinmunes/diagnóstico , Femenino , Enfermedades Hematológicas/sangre , Enfermedades Hematológicas/diagnóstico , Humanos , Hepatopatías/sangre , Hepatopatías/diagnóstico , Neoplasias/sangre , Neoplasias/diagnóstico , Embarazo , Nacimiento Prematuro/sangre , Nacimiento Prematuro/diagnóstico , Insuficiencia Renal/sangre , Insuficiencia Renal/diagnóstico
11.
Swiss Med Wkly ; 142: w13677, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23015536

RESUMEN

In population surveys of the exposure to medical X-rays both the frequency of examinations and the effective dose per examination are required. The use of the Swiss medical tariffication system (TARMED) for establishing the frequency of X-ray medical examinations was explored. The method was tested for radiography examinations performed in 2008 at the Lausanne University Hospital. The annual numbers of radiographies determined from the "TARMED" database are in good agreement with the figures extracted from the local RIS (Radiology Information System). The "TARMED" is a reliable and fast method for establishing the frequency of radiography examination, if we respect the context in which the "TARMED" code is used. In addition, this billing context provides most valuable information on the average number of radiographs per examination as well as the age and sex distributions. Radiographies represent the major part of X-ray examinations and are performed by about 4,000 practices and hospitals in Switzerland. Therefore this method has the potential to drastically simplify the organisation of nationwide surveys. There are still some difficulties to overcome if the method is to be used to assess the frequency of computed tomography or fluoroscopy examinations; procedures that deliver most of the radiation dose to the population. This is due to the poor specificity of "TARMED" codes concerning these modalities. However, the use of CT and fluoroscopy installations is easier to monitor using conventional survey methods since there are fewer centres. Ways to overcome the "TARMED" limitations for these two modalities are still being explored.


Asunto(s)
Relación Dosis-Respuesta en la Radiación , Atención al Paciente/estadística & datos numéricos , Efectos de la Radiación , Radiografía Intervencional/efectos adversos , Medición de Riesgo/métodos , Seguridad/estadística & datos numéricos , Recolección de Datos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Radiografía Intervencional/estadística & datos numéricos , Estudios Retrospectivos , Suiza
12.
Rev Med Suisse ; 8(326): 254-8, 2012 Feb 01.
Artículo en Francés | MEDLINE | ID: mdl-22364073

RESUMEN

The year 2011 was full of significant advances in all areas of medicine. Whether small or large issues, they all have an impact on daily practice in general internal medicine. For example, intravenous administration of diuretics in heart failure shows no benefit. But double dose may improve symptoms faster. Direct Xa inhibitors are emerging as alternative to anti-vitamin K. beta-blockers reduce overall mortality in COPD and do not worsen lung function significantly. Each year, the chief residents from the Department of internal medicine at the University hospital of Lausanne meet to share their readings. Twelve new therapeutic considerations of 2011 are reviewed here.


Asunto(s)
Medicina Interna/tendencias , Internado y Residencia , Hospitales Universitarios , Humanos , Suiza
13.
Vet Comp Orthop Traumatol ; 24(5): 313-9, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21792477

RESUMEN

OBJECTIVES: To quantitatively describe the intramedullary arterial supply of the adult feline tibia and determine if the arterial supply is significantly different from that of adult small dogs. METHODS: Cadaveric feline and canine pelvic limbs were obtained to prospectively investigate the intramedullary arterial supply of the tibia. A microvascular injection and modified Spalteholz bone clearing technique were used to characterize and quantify the intramedullary arterial supply of the tibia. Statistical comparisons were made between cats and dogs for the percentage of intramedullary arterial supply (arterial density) and the diameter of the nutrient artery. RESULTS: No significant difference was observed in the intramedullary arterial density between dog and cat tibiae. The feline nutrient artery diameter (0.55 ± 0.1 mm) was significantly greater than the canine nutrient artery (0.30 ± 0.04 mm) in the distal section of bone. Dogs subjectively had a greater number of branching vessels in the distal and mid-diaphyseal sections of bone when compared to cats. CLINICAL SIGNIFICANCE: Delayed fracture healing in the feline tibia does not appear to be associated with a lack of intramedullary arterial supply. A lack of diffuse arborization of the arterial supply to the middle and distal feline tibia may explain, at least in part, why feline tibial delayed or nonunions may be more common than in canine tibial fractures.


Asunto(s)
Gatos/anatomía & histología , Tibia/irrigación sanguínea , Animales , Cadáver , Perros/anatomía & histología
14.
Clin Exp Allergy ; 40(5): 786-94, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20030662

RESUMEN

BACKGROUND: Recent studies indicate that prenatal vitamin D intake may protect against the development of atopic diseases in young children. Vitamin D has been shown to induce tolerogenic antigen-presenting cells such as dendritic cells. Whether the allergy-protective potential of prenatal vitamin D is mediated through such mechanisms is, however, unknown. OBJECTIVE: To evaluate the association between prenatal vitamin D supplementation and tolerogenic antigen-presenting cells in cord blood (CB) as determined by mRNA measurement of immunoglobulin-like transcripts (ILT)3 and ILT4. METHODS: A prospective multi-centre birth cohort was established in rural areas of five European countries. Information on maternal exposures including vitamin D intake was collected by questionnaires during pregnancy. The gene expression of ILT3 and ILT4 was analysed by real-time PCR in the CB of 927 children. Maternal vitamin D supplementation was assessed in Finland and France (n=349). RESULTS: Maternal vitamin D supplementation during pregnancy was associated with an increase in the gene expression of ILT3 (P=0.012) and ILT4 (P<0.001). This association remained significant for ILT4 (P=0.020) and showed a positive trend for the gene expression of ILT3 (P=0.059) after multivariate analysis controlling for various confounders. CONCLUSIONS: Vitamin D supplementation during pregnancy may increase the mRNA levels of ILT3 and ILT4 in CB. This finding may point towards an early induction of tolerogenic immune responses by maternal vitamin D intake.


Asunto(s)
Células Presentadoras de Antígenos/inmunología , Suplementos Dietéticos , Sangre Fetal/inmunología , Expresión Génica , Hipersensibilidad Inmediata/prevención & control , Glicoproteínas de Membrana/genética , Receptores de Superficie Celular/genética , Receptores Inmunológicos/genética , Vitamina D/administración & dosificación , Adulto , Niño , Europa (Continente)/epidemiología , Femenino , Humanos , Hipersensibilidad Inmediata/epidemiología , Hipersensibilidad Inmediata/inmunología , Masculino , Embarazo , Estudios Prospectivos , ARN Mensajero/genética , Factores de Riesgo , Población Rural
15.
Vet Comp Orthop Traumatol ; 22(6): 467-72, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19876517

RESUMEN

An in vitro mechanical study was performed to compare the fatigue properties and the loads to failure of four plate designs that are used to stabilise the tibial plateau levelling osteotomy (TPLO). Seventy-two gapped osteotomy models were created using 3.5 mm versions of the following plates: a standard TPLO plate, a low profile TPLO plate, a locking TPLO plate (LocP), and a broad locking TPLO plate (bLocP). The 18 constructs for each plate design were sub-divided into three identical groups of six. Six constructs were mounted in a materials testing device and subjected to cyclic compressive loading until failure was observed or one-million cycles were achieved. Additionally, six constructs of each plate design were tested in compressive axial loading and six others in four-point bending in a load-to-failure manner. To provide residual strength comparisons, the six constructs undergoing cyclic fatigue compression testing were also tested in axial compressive loading. There were not any significant differences in stiffness between plates tested in axial compressive loading. However, mean loads at failure were higher for the LocP and bLocP constructs. The bLocP had a significantly higher mean stiffness and mean load at failure compared to the other constructs tested in four-point bending.


Asunto(s)
Placas Óseas/veterinaria , Osteotomía/veterinaria , Animales , Fenómenos Biomecánicos , Perros , Modelos Biológicos , Osteotomía/instrumentación , Rodilla de Cuadrúpedos/cirugía , Tibia/cirugía
16.
Proc Natl Acad Sci U S A ; 105(6): 2209-13, 2008 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-18238904

RESUMEN

The capacity to use tools is a fundamental evolutionary achievement. Its essence stands in the capacity to transfer a proximal goal (grasp a tool) to a distal goal (e.g., grasp food). Where and how does this goal transfer occur? Here, we show that, in monkeys trained to use tools, cortical motor neurons, active during hand grasping, also become active during grasping with pliers, as if the pliers were now the hand fingers. This motor embodiment occurs both for normal pliers and for "reverse pliers," an implement that requires finger opening, instead of their closing, to grasp an object. We conclude that the capacity to use tools is based on an inherently goal-centered functional organization of primate cortical motor areas.


Asunto(s)
Corteza Motora/fisiología , Neuronas/fisiología , Animales , Electromiografía , Femenino , Macaca nemestrina , Masculino , Corteza Motora/citología
17.
Eur Respir J ; 31(4): 860-8, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18057057

RESUMEN

The need for updated spirometric reference values to be used on European populations is widely acknowledged, especially for subjects aged >70 yrs. Their reference values are generally based on extrapolations. The aim of the present study was to calculate reference values for lung function screening of healthy, never-smoking adults aged 18-80 yrs and to compare them with the most widely used reference equations. Results of screening spirometry of 8,684 healthy, never-smoking adults were used to calculate mean values and fifth percentiles of lung function variables. The European Community of Coal and Steel (ECCS) reference equations underestimate forced expiratory volume in one second (FEV(1)) and forced vital capacity (FVC). For example, in 50-yr-old males (height 175 cm), lower limits of normal for FEV(1) are underestimated by 198 mL, and for FVC by 210 mL. In 50-yr-old females (height 165 cm), lower limits of normal for FEV(1) are underestimated by 191 mL, and for FVC by 270 mL. The decline of FVC in elderly subjects is steeper than predicted by the ECCS. Reference equations derived from spirometry data locally collected in a practical setting by well-trained personnel might be more appropriate for everyday use than generally used equations based on data from scientific studies in the distant past.


Asunto(s)
Tamizaje Masivo , Modelos Biológicos , Fenómenos Fisiológicos Respiratorios , Adolescente , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valores de Referencia , Pruebas de Función Respiratoria
18.
Vet Comp Orthop Traumatol ; 20(4): 264-8, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-18038001

RESUMEN

Modifications of a Type 1a external skeletal fixator (ESF) frame were evaluated by alternately placing transfixation pins on opposite sides of the connecting rod (Type 1a-MOD) or by placing additional connecting rods on either of the two inside (Type 1a-INSIDE) or two outside (Type 1a-OUTSIDE) transfixation pins. The objective of this study was to evaluate the stiffness of these modifications in terms of axial compression (AC), cranial-caudal bending (CCB), and medial-lateral bending (MLB). We hypothesized that these designs would allow significant increase in unilateral frame stiffness, over Type 1a, without proportional increase in frame complexity or technical difficulty of application. All of the ESF frames were constructed using large IMEX SKtrade mark clamps, 3.2 mm threaded fixation pins, 9.5 mm carbon fibre connecting rods and Delrin rods as bone models. Nine, eight pin frames of each design were constructed, and subjected to repetitive non-destructive loading forces (AC, CCB, MLB) using a materials testing machine. Frame construct stiffness for each force (AC, CCB, MLB) was derived from load-deformation curve analysis and displayed in N/mm. Data revealed the 1a-MOD and 1a-OUTSIDE constructs had significantly increased stiffness in CCB and AC as compared to the Type 1a constructs while all of the modified constructs were significantly stiffer in MLB than the Type 1a constructs.


Asunto(s)
Fijadores Externos/veterinaria , Fracturas Óseas/veterinaria , Animales , Fenómenos Biomecánicos , Diseño de Equipo , Fracturas Óseas/cirugía , Ensayo de Materiales , Fracturas del Radio/cirugía , Fracturas del Radio/veterinaria , Fracturas de la Tibia/cirugía , Fracturas de la Tibia/veterinaria
19.
Appl Phys B ; 75(2-3): 351-7, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12599401

RESUMEN

Pulsed thermoelectrically cooled QC-DFB lasers operating at 15.6 micrometers were characterized for spectroscopic gas sensing applications. A new method for wavelength scanning based on repetition rate modulation was developed. A non-wavelength-selective pyroelectric detector was incorporated in the sensor configuration giving the advantage of room-temperature operation and low cost. Absorption lines of CO2 and H2O were observed in ambient air, providing information about the concentration of these species.


Asunto(s)
Atmósfera/química , Dióxido de Carbono/análisis , Monitoreo del Ambiente/instrumentación , Rayos Láser , Agua/análisis , Electricidad , Diseño de Equipo , Gases/análisis , Teoría Cuántica , Espectrofotometría Infrarroja/instrumentación
20.
FEBS Lett ; 507(3): 351-6, 2001 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-11696370

RESUMEN

For understanding the mechanism(s) relating inflammation to corticosteroid action, the effect of tumour necrosis factor-alpha (TNF-alpha) on 11beta-hydroxysteroid dehydrogenase type 2 (11beta-HSD2), the enzyme regulating access of 11beta-hydroxycorticosteroids to receptors, was studied in LLC-PK(1) cells. We observed (i) NAD-dependent enzyme activity and mRNA for 11beta-HSD2, but not 11beta-HSD1, (ii) increasing 11beta-HSD2 activity with increasing degree of differentiation and (iii) a concentration-dependent down-regulation by TNF-alpha, phorbol myristate acetate (PMA) or glucose of activity and mRNA of 11beta-HSD2. The decrease of activity and mRNA by glucose and PMA, but not that by TNF-alpha, was abrogated by the protein kinase C inhibitor GF-109203X. The effect of TNF-alpha on 11beta-HSD2 was reversed by inhibiting the mitogen-activated protein kinases ERK with PD-098050 and p38 by SB-202190, or by activating protein kinase A with forskolin. Overexpression of MEK1, an ERK activator, down-regulated the 11beta-HSD2 activity. In conclusion, TNF-alpha decreases 11beta-HSD2 activity and thereby enhances glucocorticoid access to glucocorticoid receptors to modulate the inflammatory response.


Asunto(s)
Glucocorticoides/metabolismo , Hidroxiesteroide Deshidrogenasas/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , 11-beta-Hidroxiesteroide Deshidrogenasa de Tipo 2 , Animales , Células Cultivadas , Colforsina/farmacología , Corticosterona/metabolismo , Corticosterona/farmacología , Proteínas Quinasas Dependientes de AMP Cíclico/antagonistas & inhibidores , Proteínas Quinasas Dependientes de AMP Cíclico/efectos de los fármacos , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Regulación hacia Abajo , Activación Enzimática , Inhibidores Enzimáticos/farmacología , Flavonoides/farmacología , Glucosa/metabolismo , Glucosa/farmacología , Hidroxiesteroide Deshidrogenasas/efectos de los fármacos , Hidroxiesteroide Deshidrogenasas/genética , Imidazoles/farmacología , Indoles/farmacología , Maleimidas/farmacología , Proteínas Quinasas Activadas por Mitógenos/antagonistas & inhibidores , Proteínas Quinasas Activadas por Mitógenos/efectos de los fármacos , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Piridinas/farmacología , Acetato de Tetradecanoilforbol/farmacología , Factor de Necrosis Tumoral alfa/farmacología
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