RESUMEN
The Schmallenberg virus (SBV) has recently emerged in Europe, causing losses to the domestic livestock. A retrospective analysis of serodata was conducted in France for estimating seroprevalence of SBV among six wildlife species from 2011-2012 to 2013-2014, that is during the three vector seasons after the emergence of the SBV in France. Our objective was to quantify the exposure of wildlife to SBV and the potential protective effect of elevation such as previously observed for bluetongue. We also compared the spatiotemporal trends between domestic and wild animals at the level of the departments. We tested 2050 sera using competitive ELISA tests. Individual and population risk factors were further tested using general linear models among 1934 individuals. All populations but one exhibited positive results, seroprevalence up to 30% being observed for all species. The average seroprevalence did not differ between species but ranged from 0 to 90% according to the area and period, due to the dynamic pattern of infection. Seroprevalence was on average higher in the lowlands compared to areas located up to 800 m. Nevertheless, seroprevalence above 50% occurred in areas located up to 1500 m. Thus, contrary to what had been observed for bluetongue during the late 2000s in the same areas, SBV could spread to high altitudes and infect all the studied species. The spatial spread of SBV in wildlife did not fully match with SBV outbreaks reported in the domestic livestock. The mismatch was most obvious in mountainous areas where outbreaks in wildlife occurred on average one year after the peak of congenital cases in livestock. These results suggest a much larger spread and vector capacity for SBV than for bluetongue virus in natural areas. Potential consequences for wildlife dynamics are discussed.
Asunto(s)
Animales Salvajes/virología , Infecciones por Bunyaviridae/epidemiología , Orthobunyavirus/aislamiento & purificación , Animales , Lengua Azul/epidemiología , Brotes de Enfermedades , Ensayo de Inmunoadsorción Enzimática , Francia/epidemiología , Estudios Retrospectivos , Factores de Riesgo , Estaciones del Año , Estudios SeroepidemiológicosRESUMEN
Bluetongue (BT) was monitored in wildlife in France during two consecutive years corresponding to contrasting incidence rates in livestock: in 2008 at the peak of domestic outbreaks and in 2009 when very few outbreaks were observed. The disease status of 2 798 ruminants comprising 837 red deer (Cervus elaphus) was explored using ELISA test on serum and real-time RT-PCR test on blood or spleen. A large proportion of red deer were seropositive and positive to RT-PCR in 2008, but also in 2009 (seroprevalence: 47.1% and 24.3%), suggesting that red deer could maintain infection when domestic incidence was negligible. By contrast, low seroprevalence (<3%) and few RT-PCR positive results were observed in other wild ruminant species, which rather appeared thus as dead-end hosts. The risk factors of bluetongue circulation during the periods of high (2008) and low (2009) domestic incidence were explored in red deer using logistic mixed models. In this species, prevalence has been mainly influenced by the initial peak of BT in livestock, but also by environmental factor such as elevation and edge density between forest and pastures. Surprisingly, cattle density has a negative influence on prevalence in red deer, possibly due to the protective effect of cattle regarding midges' bites and/or to still unexplained factors dealing with the host/midge interface. To our knowledge, this study is the first attempt at measuring the effect of landscape and wildlife/domestic interface on BT prevalence in wildlife in Europe.
Asunto(s)
Lengua Azul/epidemiología , Ganado/virología , Rumiantes/virología , Animales , Virus de la Lengua Azul/aislamiento & purificación , Ciervos/virología , Francia/epidemiología , Prevalencia , Factores de Riesgo , Estudios SeroepidemiológicosRESUMEN
AIM: Assess the degree of satisfaction of medical students regarding their teaching of gynaecology and obstetrics at the medical faculty of Paris-VII in 2008-2009. The aim is to improve the quality of teaching and learning tools mainly with a view to preparing for the national examination competition. MATERIALS AND METHODS: This is an observational study on a cohort of 116 students enrolled in 3rd year of graduate medical education, Faculty Paris-VII Denis-Diderot, who was asked to respond anonymously to a questionnaire of satisfaction comprising 13 questions. RESULTS: Participation in course organized by the faculty is 62%. Ninety-three percent of students are enrolled in private lessons to prepare the national examination competition. Eighty-one percent of students believe that teaching private courses is better than the courses offered by the faculty. Sixty-two percent of students consider a medium (Internet or CD-ROM). Quality could replace traditional media's theory of education. Ninety percent of students use as a main working the same book sold in commerce. Among them, 98.2% considered that the external training is useful in the preparation of the national examination competition. DISCUSSION: It seems that teaching traditional academic lectures of gynaecology and obstetrics is not the preferred method of teaching students in 5th year of medicine. They prefer the education provided by the private preparedness at national examination competition, in the form of clinical cases, even if the courses offered by the faculty try to adapt in this form. The book remains the primary medium of work, but many students believe that a computer could replace or supplement the traditional media. The internship hospital services in gynaecology and obstetrics compulsory Paris-VII seems helpful in learning the specialty including in the context of the national examination class.
Asunto(s)
Educación de Postgrado en Medicina/normas , Obstetricia/educación , Satisfacción Personal , Evaluación de Programas y Proyectos de Salud , Estudiantes de Medicina , Estudios de Cohortes , Humanos , Paris , Encuestas y CuestionariosRESUMEN
Toxoplasma gondii isolates have been classified into 3 genetic types. Little is known about genotypes of T. gondii isolates in wild animals in Europe. In this report, genotypes of T. gondii isolates from wildlife in France are described. Sera from wildlife were tested for antibodies to T. gondii with the modified agglutination test, and the hearts from animals with titers superior or equal to 1:6 were bioassayed individually in mice. T.gondii was isolated from 9 of 14 seropositive red foxes (Vulpes vulpes), 12 of 33 roe deer (Capreolus capreolus), 1 of 4 deer (Cervus elaphus), 1 of 7 mouflons (Ovis gmelini musimon) and 1 of 2 common mallards (Anas platyrhynchos). No isolate was obtained by bioassay in mice of 1 fallow deer (Dama dama) and of 3 European brown hares (Lepus europaeus). Genotyping of the 24 isolates using PCR-RFLP and microsatellite markers indicated that all were type II and none of these Toxoplasma isolates was virulent for mice.
Asunto(s)
Animales Salvajes , Toxoplasma/genética , Toxoplasmosis Animal/parasitología , Animales , Ciervos , Patos , Zorros , Francia/epidemiología , Liebres , Ratones , Ovinos , Toxoplasmosis Animal/epidemiologíaRESUMEN
BACKGROUND: Obesity is a risk factor for gastroesophageal reflux disease (GERD) and for obstructive sleep apnea (OSA). Our aim was to evaluate in morbidly obese patients the prevalence of OSA and GERD and their possible relationship. METHODS: Morbidly obese patients [body mass index (BMI) >40 or >35 kg/m(2) in association with comorbidities] selected for bariatric surgery were prospectively included. Every patient underwent a 24-h pH monitoring, esophageal manometry, and nocturnal polysomnographic recording. RESULTS: Sixty-eight patients [59 women and 9 men, age 39.1 +/- 11.1 years; BMI 46.5 +/- 6.4 kg/m(2) (mean +/- SD)] were included. Fifty-six percent of patients had an abnormal Demester score, 44% had abnormal time spent at pH <4, and 80.9% had OSA [apnea hypopnea index (AHI) >10] and 39.7% had both conditions. The lower esophageal sphincter (LES) pressure was lower in patients with GERD (11.6 +/- 3.4 vs 13.4 +/- 3.6 mm Hg, respectively; P = 0.039). There was a relationship between AHI and BMI (r = 0.337; P = 0.005). Patients with OSA were older (40.5 +/- 10.9 vs 33.5 +/- 10.4 years; P = 0.039). GERD tended to be more frequent in patients with OSA (49.1% vs 23.1%, respectively; P = 0.089). There was no significant relationship between pH-metric data and AHI in either the 24-h total recording time or the nocturnal recording time. In multivariate analysis, GERD was significantly associated with a low LES pressure (P = 0.031) and with OSA (P = 0.045) but not with gender, age, and BMI. CONCLUSION: In this population of morbidly obese patients, OSA and GERD were frequent, associated in about 40% of patients. GERD was significantly associated with LES hypotonia and OSA independently of BMI.
Asunto(s)
Reflujo Gastroesofágico/epidemiología , Obesidad Mórbida/epidemiología , Apnea Obstructiva del Sueño/epidemiología , Adulto , Cirugía Bariátrica , Comorbilidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Obesidad Mórbida/cirugía , PolisomnografíaRESUMEN
The mouflon population of Caroux-Espinouse, southern France, inhabits a highly seasonal area with dry summers. We monitored summer lamb survival during a severe drought in 2003, from early June to late August. The survival of 35 radio-tagged lambs over nine two-week periods was strongly affected by the timing of rainfall. Survival depended on the amount of rainfall recorded at a given 14 day period and in the previous 14-21 day period. Survival was not influenced by the exceptionally high mean daily temperature recorded during some periods. Male lamb survival (0.68) tended to be less than female survival (0.81), although not significantly, possibly because of a low sample size. The high lamb mortality (25.7%) recorded during a four-month period is much higher than previous estimates of first-year mortality (less than 10%). We recommend accounting for climatic variation in summer when studying the population dynamics of ungulates.
Asunto(s)
Desastres , Estaciones del Año , Ovinos/fisiología , Análisis de Varianza , Animales , Recolección de Datos/instrumentación , Femenino , Francia , Masculino , Modelos Biológicos , Mortalidad , Dinámica Poblacional , Factores Sexuales , TelemetríaRESUMEN
OBJECTIVES: Student attendance to lectures in French medical schools is often poor. We surveyed undergraduate medical students in our medical school, repeating a similar survey conducted ten years earlier. The results are presented with the conclusions of the faculty seminar that followed this survey. METHODS: A closed item questionnaire was distributed in June, 1998, through the hospital wards where the students were posted. After two reminders, the final response rate was 71% (247/348). RESULTS: Overall, 71% of the students declared that they never, or only occasionally, attended lectures in the medical school. Reasons included lack of time (75%), the curriculum diverging from the program of the selective examination that gives access to graduate specialization programs (59%), or insufficient practical clinical content (36%); 46% believed that this teaching prepared them to practice family medicine (11% some specially), and 92% that the way it was organized was not compatible with preparing for the selective examination. On the other hand, 75% of the students in the final two years of the curriculum declared that attending regularly special preparation seminars for the selective examination, to succeed at this test (91%), but also to prepare for family practice (25%). Respectively, 75%, 68% and 66% declared that undergraduate medical courses should, ideally, prepare them for the selective examination, but also for the practice of family medicine, and for graduate medical education. CONCLUSIONS: These results echoed the difficulties of the faculty of the medical school to reconcile preparing students both for their future medical practice and for the selective examination. Two working groups were asked to identify independently appropriate educational objectives according to each perspective: their conclusions appeared to be quite compatible. Based on these conclusions, institutional objectives were ratified to guide the educational policy of our medical school, including the following: to reinforce the consistency and progressiveness of the curriculum; to promote active and autonomous student learning approaches; to develop faculty teaching skills, curriculum evaluation and recognition of teaching activities.
Asunto(s)
Curriculum , Educación de Pregrado en Medicina/normas , Recolección de Datos , Educación de Pregrado en Medicina/estadística & datos numéricos , Femenino , Francia , Adhesión a Directriz , Humanos , MasculinoRESUMEN
The "AVL OPTI 1" (AVL Medical Instruments, Saint-Ouen l'Aumone, France), a completely automated portable blood gas analyzer, was chosen because of its accuracy under usual sea-level conditions and because of its new technology which broadens the possibilities for in-flight blood determinations: a) a single use cassette made of plexyglass containing the measurement chamber and the aligned sensors required for pO2, pcO2 and pH determination; b) calibration coefficients memorized in a bar code label fixed on the packing material; c) a quality control of each individual cassette prior to the measurement and at least once a day by two standard reference cassettes simulating high and low levels of pH, pcO2 and pO2; and d) a fully automatic introduction of the blood sample. The complete analytical cycle requires about 3 min with a sample volume of 80 microL of whole blood. After the measurement, the cassette containing blood sample is destroyed. Moreover, this device uses optical electrodes or "optodes" (fluorescence sensors). We tested the accuracy and imprecision of pO2 and pcO2 sensors on fresh blood which was equilibrated with four different gas mixtures at four different altitudes (250, 8000, 10,000 and 13,000 ft), simulated in a decompression chamber. Gas measurement optodes had linear responses and were accurate for all measured pO2 and pco2 values (n = 66), except for at high values of PO2 (>150 mmHg) and pco2 (>65 mmHg). The pressure value given by the AVL OPTI 1 was controlled before the experiment began and during the different depression levels. Barometric pressure results showed: a) concordance of pressure values with those of ground instrumentation; b) stable response; and c) absence of hysteresis. We conclude that the performance of the AVL OPTI 1 is satisfactory during inflight conditions.
Asunto(s)
Medicina Aeroespacial , Ambulancias Aéreas , Análisis de los Gases de la Sangre/instrumentación , Dióxido de Carbono/sangre , Oxígeno/sangre , Altitud , Análisis de Varianza , Presión Atmosférica , Humanos , Modelos Lineales , Reproducibilidad de los ResultadosRESUMEN
Seven normotensive untreated patients with obstructive sleep apnea (OSA) and five control subjects without OSA were compared. Patients with cardiac dilation, chronic airflow limitation, liver and kidney disease, or diabetes mellitus were excluded. Change in pressure-heart rate relation to alpha-adrenergic stimulation (P-HRR), extracellular volume (ECV), and plasma volume (Vp) were measured during daytime. Plasma atrial natriuretic peptide (ANP), plasma renin and aldosterone concentrations were obtained at 1 hour intervals during the night. A mean apnea/hypopnea index (AHI) of 52.2 +/- 23.9/h and a mean lowest arterial oxygen saturation (SaO2) of 61.2 +/- 19.3% (mean +/- SD) were determined from polysomnographic monitoring in the patient group. Release of ANP was significantly higher during sleep in OSA patients than in control subjects (P < .01), with a maximum concentration between 4 and 6 AM in the former. Daytime ECV was significantly higher (P < .05) and Vp significantly lower (P < .05) in OSA patients. Night maximum concentration of ANP (max ANP) was negatively related to AHI (P < .05). P-HRR was negatively related to AHI (P < .05) and positively related to max ANP (P < .05). In conclusion, OSA syndrome alters hormonal system control of body fluid compartment regulation. The decreased response in night max ANP secretion in the most severe OSA patients could be explained by the smaller Vp observed in these patients, decreasing atrial and ventricular pressure loading. Furthermore, alteration of P-HRR, correlated to AHI and max ANP, strengthens the hypothesis that patients who develop hypertension are those in whom the protective mechanism of ANP release failed.
Asunto(s)
Agonistas alfa-Adrenérgicos/administración & dosificación , Presión Sanguínea/efectos de los fármacos , Frecuencia Cardíaca/efectos de los fármacos , Síndromes de la Apnea del Sueño/fisiopatología , Adulto , Aldosterona/sangre , Factor Natriurético Atrial/sangre , Humanos , Persona de Mediana Edad , Renina/sangre , Síndromes de la Apnea del Sueño/sangre , Síndromes de la Apnea del Sueño/tratamiento farmacológicoRESUMEN
The aim of this study was to determine the value of bronchoscopy in the early diagnosis of inhalation injury. A total of 130 burn patients underwent bronchoscopy on admission to a specialized center. In order to validate the method and the bronchoscopist's conclusions, they underwent staged bronchial biopsies. Using the histologic findings as the "gold standard," bronchoscopy proved to be sensitive (sensitivity, 0.79) and highly specific (specificity, 0.94) for the diagnosis of inhalation injury. In addition, it was more reliable than the circumstances of the injury, the clinical findings, and complementary tests. In a one-dimensional analysis, bronchoscopy-proven inhalation injury was one of the most strongly predictive variables for the onset of ARDS and death. The analysis of survival curves confirmed that inhalation injury portends a bad outcome in burn patients. It was used to predict the likelihood of ARDS and death at the time of admission with a view to early specific treatment.
Asunto(s)
Broncoscopía/métodos , Quemaduras por Inhalación/diagnóstico , Tecnología de Fibra Óptica/métodos , Glotis/lesiones , Adulto , Biopsia , Superficie Corporal , Quemaduras por Inhalación/complicaciones , Quemaduras por Inhalación/mortalidad , Quemaduras por Inhalación/terapia , Causalidad , Femenino , Humanos , Puntaje de Gravedad del Traumatismo , Masculino , Persona de Mediana Edad , Admisión del Paciente , Pronóstico , Estudios Prospectivos , Reproducibilidad de los Resultados , Síndrome de Dificultad Respiratoria/etiología , Síndrome de Dificultad Respiratoria/mortalidad , Sensibilidad y Especificidad , Análisis de SupervivenciaRESUMEN
We assessed (1) the sensitivity and specificity of exercise oxygen saturation measurement (EOS) for the diagnosis of Pneumocystis carinii pneumonia (PCP); and (2) the cost of introducing this indirect diagnostic test compared with that of standard diagnostic strategies for PCP. In a prospective study, 85 HIV-infected patients with suspected PCP underwent EOS, followed by induced sputum (IS) and bronchoalveolar lavage (BAL) if IS was negative for P. carinii. The prevalence of PCP was 0.22, the sensitivity of IS was 0.6, and its specificity was perfect. The cost ratios of IS to BAL and EOS to BAL were 0.1 and 0.2, respectively. A desaturation of three points was the best cutoff point, giving perfect sensitivity and a specificity of 0.77. The cost analysis showed that the introduction of EOS into diagnostic strategies for PCP is highly justified when the local prevalence is low. Exercise oxygen saturation measurement is simple and safe, and the results are available rapidly; its sensitivity is perfect and its specificity good. Its economic utility depends on its cost and the local prevalence of PCP in the test population.
Asunto(s)
Infecciones Oportunistas Relacionadas con el SIDA/economía , Monitoreo de Gas Sanguíneo Transcutáneo/economía , Prueba de Esfuerzo/economía , Neumonía por Pneumocystis/economía , Infecciones Oportunistas Relacionadas con el SIDA/diagnóstico , Infecciones Oportunistas Relacionadas con el SIDA/epidemiología , Adulto , Monitoreo de Gas Sanguíneo Transcutáneo/estadística & datos numéricos , Líquido del Lavado Bronquioalveolar/economía , Análisis Costo-Beneficio , Prueba de Esfuerzo/estadística & datos numéricos , Femenino , Infecciones por VIH/diagnóstico , Infecciones por VIH/economía , Infecciones por VIH/epidemiología , VIH-1 , Humanos , Masculino , Persona de Mediana Edad , Paris/epidemiología , Pneumocystis/aislamiento & purificación , Neumonía por Pneumocystis/diagnóstico , Neumonía por Pneumocystis/epidemiología , Prevalencia , Estudios Prospectivos , Curva ROC , Sensibilidad y Especificidad , Esputo/microbiologíaRESUMEN
The following study explores the possibility that zolpidem, a new hypnotic agent derived from imidopyridine, may induce changes in ventilatory function in normal subjects. The study, conducted double-blind on 16 subjects (eight men and eight women, aged 21 to 33 years) was undertaken in two successive phases: phase A with a cross-over, intended to compare the ventilatory effects of 10 mg oral dose of diazepam with a placebo, and then phase B, with a Latin square design, intended to compare the effects of 10 and 20 mg oral doses of zolpidem with 10 mg oral doses of diazepam and a placebo. Central inspiratory drive was assessed by occlusion pressure (P0.1) and breathing pattern in air and during carbon dioxide rebreathing. Measurements were performed one and three hours after each drug or placebo administration. Zolpidem did not affect tidal volume (Vt), slopes S1, S2 or P0.1, but decreased the duration of the phases of the respiratory cycle ti by 14% (p less than 0.01) and ttot by 15% (p = 0.03) after three hours post dosing without any change in ventilation, Vt/ti or ti/ttot. Nevertheless, these timing changes, although statistically significant, seem to have no clinical relevance to overall ventilation regulation in normal subjects. On the other hand, diazepam slightly changed S2 at three hours post dosing (0.14 +/- 0.07 versus 0.17 +/- 0.10 after the placebo; p = 0.06) without modifying the other parameters.
Asunto(s)
Diazepam/farmacología , Hipnóticos y Sedantes/farmacología , Piridinas/farmacología , Respiración/efectos de los fármacos , Administración Oral , Adulto , Diazepam/administración & dosificación , Método Doble Ciego , Femenino , Humanos , Masculino , Piridinas/administración & dosificación , Pruebas de Función Respiratoria , Volumen de Ventilación Pulmonar/efectos de los fármacos , ZolpidemRESUMEN
Oxyhemogloblin affinity (P50 at pH 7.4, PaCO2 = 40 mm Hg, temperature = 37 degrees C) and 2,3-DPG concentration were assessed in 15 nonsmokers (14 men and one woman 46 to 63 yr of age) with sleep apnea syndrome (SAS) and in 10 normal subjects (eight men and two women 22 to 48 yr of age). In patients with SAS, mean nocturnal apnea index was 46 +/- 20/h, and mean nocturnal SO2 was 86 +/- 6% versus 94.6 +/- 1.8% during the daytime. Daytime mean P50 of the patients was 28.5 +/- 1.2 mm Hg versus 27.1 +/- 0.3 mm Hg in the normal subjects (p less than 0.05). Daytime mean 2.3-DPG was 1.23 +/- 0.25 moles DPG/mole hemoglobin versus 0.80 +/- 0.15 (p less than 0.05). Significant correlations were found in patients between P50 and mean nocturnal SO2 (r = -0.62, p less than 0.01) and between P50 and 2,3-DPG (r = 0.68, p less than 0.01). The measurements were repeated in five patients after surgical or positive-pressure treatment. P50 and 2,3-DPG both decreased and returned to normal values. In conclusion, the oxyhemoglobin dissociation curve is shifted to the right in patients with SAS and there is an increase in 2,3-DPG. These could be protective mechanisms against the development of polycythemia, pulmonary hypertension, and cor pulmonale.
Asunto(s)
Oxihemoglobinas/metabolismo , Síndromes de la Apnea del Sueño/sangre , 2,3-Difosfoglicerato , Dióxido de Carbono/sangre , Ácidos Difosfoglicéricos/sangre , Eritrocitos/metabolismo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Oxígeno/sangre , Síndromes de la Apnea del Sueño/terapiaRESUMEN
The association of salpingoplasty to the previously described nymphoplasty improves the result of the vaginoplasty of the Rokitansky-Kuster-Hauser syndrome. The pediculate mucous flaps obtained by cleavage of the labium minus are linked with the vascularized tubal flaps from the lumbo-ovarian ligament. In the present observation, this dressing up technique of the new vagina has enabled a quick and complete epithelialization, avoiding a progressive obturation from inwards towards the surface, without the use of a mandrin in the long run.
Asunto(s)
Trompas Uterinas/cirugía , Vagina/anomalías , Vagina/cirugía , Vulva/cirugía , Adulto , Epitelio/fisiología , Femenino , Humanos , Procedimientos Quirúrgicos Operativos/métodos , Vagina/fisiologíaRESUMEN
Effect of He-O2-breathing (79.1%:20.9%) compared to air-breathing on inspiratory ventilation (VI) and its different components [tidal volume (VT), the duration of the phases of each respiratory cycle (tI, tTOT)] as well as on inspiratory mouth occlusion pressure (P0.1) were studied in six normal men at rest and during 72 constant-load exercises (90 W) over a much longer period than in previous studies. Results showed that, irrespective of the order of administration of the two gases (7 min air----7 min He-O2 or vice versa): at rest, P0.1 decreased during He-O2 inhalation but no changes in VI and breathing pattern were detectable; during exercise, sustained He-induced hyperventilation was observed without any change in the absolute value of P0.1; increase in P0.1 between the resting period and exercise (delta P0.1) was significantly higher during He-O2-breathing than during air breathing; this He-induced hyperventilation was associated with a sustained increase in VT/tI, but with constant tI/tTOT. Helium-breathing during exercise cannot be a simple situation of resistance unloading, as has been suggested. We conclude that He-O2-breathing, after the initial compensation period, induces reflex changes in ventilatory control with an increase in inspiratory neural drive. Moreover, it appears that exercise P0.1 is not a legitimate index of inspiratory neural drive whenever rest P0.1 changes according to the nature of the inhaled gas mixture.
Asunto(s)
Adaptación Fisiológica , Resistencia de las Vías Respiratorias , Ejercicio Físico , Respiración , Adulto , Ciclismo , Humanos , Masculino , Persona de Mediana Edad , Fisiología/instrumentación , DescansoRESUMEN
This study describes a new method for routine total haemoglobin determination by conversion to haemiglobin (Hi), and compares it with the haemiglobin cyanide (HiCN) method. Experiments were performed in two phases. Firstly, the absorbance coefficient (epsilon Hi,500mm) at pH = 6.8, determined from 24 blood samples, was found to be 998 +/- 31 m2.mol-1. Secondly, using this value of epsilon, the range of haemoglobin concentration measured was 3.7 to 19.2 mmol.l-1 (6 to 31 g.dl-1). The correlation data shows an excellent correlation (r = 0.982, p less than 0.001) with the reference procedure. Reproducibility and accuracy were shown to be good.
Asunto(s)
Hemoglobinometría/métodos , Metahemoglobina/análisis , Estudios de Evaluación como Asunto , Metahemoglobina/análogos & derivadosRESUMEN
The effects of two vasodilators, papaverine and pentoxifylline (a methylxanthine derivative), on liver function after 19 hr hypothermic preservation were investigated. Hypothermic preservation was performed according to the standard technique, and liver hemodynamics and function were studied during 70 min immediately after reperfusion in an isolated perfused rat liver system. No significant changes occurred after hypothermic storage for 5 hr. However, when the storage was prolonged to 19 hr, bile flow and taurocholate intrinsic clearance were significantly reduced; transaminase release was markedly increased and histological studies demonstrated centrilobular necrosis. Concomitantly, liver blood flow was significantly reduced and intrahepatic vascular resistance was increased. Papaverine and pentoxifylline administered during preservation and at the time of reperfusion significantly improved all parameters. The improvement was more pronounced after pentoxifylline, and this group showed no significant difference in any of the studied parameters from the control livers. The results show that two vasodilators significantly protect the liver during long hypothermic preservation. The data suggest that abnormalities of liver microcirculation are of major importance in the pathogenesis of liver injury after hypothermic storage.
Asunto(s)
Hemodinámica/efectos de los fármacos , Hígado/efectos de los fármacos , Preservación de Órganos/métodos , Papaverina/farmacología , Pentoxifilina/farmacología , Daño por Reperfusión/prevención & control , Teobromina/análogos & derivados , Animales , Bilis/metabolismo , Técnicas In Vitro , Circulación Hepática/efectos de los fármacos , Trasplante de Hígado , Masculino , Tamaño de los Órganos/efectos de los fármacos , Vena Porta/fisiología , Ratas , Ratas Endogámicas , Ácido Taurocólico/metabolismo , Factores de Tiempo , Resistencia Vascular/efectos de los fármacosRESUMEN
Measurement of blood gas values during air transport of intensive care patients must take into account the extreme inflight variations in pressure. We tested the accuracy and reliability of the Eschweiler 2500-11 apparatus, with its incorporated pressure transducer, on four different gas mixtures equilibrated with fresh blood at two different altitudes simulated in a decompression chamber. Results for the pressure transducer show: 1) concordance of pressure values with those of ground instrumentation; 2) stable response; and 3) absence of hysteresis. Gas measurement electrodes were shown to have linear responses and were accurate for all tested values except very low PCO2 and very high PO2 figures. We conclude that the performance of this device is satisfactory during inflight conditions.
Asunto(s)
Altitud , Análisis de los Gases de la Sangre/instrumentación , Medicina Aeroespacial , Cámaras de Exposición Atmosférica , Dióxido de Carbono/fisiología , Electrodos , Humanos , Oxígeno/fisiología , Presión Parcial , Presión , Tonometría Ocular , TransductoresAsunto(s)
Caracteres Sexuales , Maduración Sexual , Adolescente , Conducta del Adolescente , Imagen Corporal , Femenino , Humanos , Masculino , Autoimagen , Conducta SexualRESUMEN
Temporal changes in ventilation (VI) and arterial blood gases after substitution of helium (He) for nitrogen were studied in normal man during constant load exercises of 14 min duration (30 and 90 W). An abrupt switch of helium for air breathing (protocol 1; 5 subjects), or vice-versa (protocol 2; 4 subjects), was made at the 7th min. Whatever the work loads, the effect of He appeared rapidly: higher values of VI (protocol 1) were observed throughout the 7 min period of He-O2 breathing, but were only significant (p less than or equal to 0.05) during the first minute after substitution at 90 W. Reverse pattern was observed in protocol 2. Helium induced alveolar hyperventilation: sustained and significant hypocapnia (p less than or equal to 0.05) was observed during helium breathing. This effect does not seem to be a consequence of pulmonary gas exchange disturbance, in that concomitant Po2 was normal. It is suggested that He could have evoked a reflex which overrode humoral regulation. Significant increase in ventilatory CO2 responses at rest during He-O2 compared to air breathing in seven subjects (p less than or equal to 0.01) seems to confirm this hypothesis.