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It was shown in the literature that ethanol locks have a positive effect on preventing catheter-related infections in patients with central venous catheters without causing any microbial resistance. However, ethanol is known to interact with polyurethanes. The consequences of this interaction on the catheter surface properties were studied as it can impact the biocompatibility of the material and the adhesion phenomena onto the surface. No physical and chemical degradation was put into evidence, but low molecular weight compounds such as additives were extracted from the catheter bulk or migrated and exudated onto its surface. Nevertheless, as far as bacterial adhesion is concerned, after the catheter was locked and the lock removed, the surface modifications promoted no adhesion.
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Infecciones Relacionadas con Catéteres , Catéteres Venosos Centrales , Humanos , Etanol/farmacología , Poliuretanos , Adhesión Bacteriana , Catéteres Venosos Centrales/efectos adversos , Catéteres Venosos Centrales/microbiología , Infecciones Relacionadas con Catéteres/etiología , Infecciones Relacionadas con Catéteres/microbiologíaRESUMEN
OBJECTIVES: To identify predictive factors of readmission after day-case rhinologic surgery. METHODS: A 2-year retrospective chart review of patients scheduled for ambulatory sinonasal surgery in a tertiary medical center was conducted. The operating room and the anesthetic files were screened to identify demographic data, types of procedure, comorbidities and post-operative complications. RESULTS: From January 2014 to January 2016, 924 outpatient sinonasal procedures were identified. The overall readmission rate within the 30-postoperative days was 5.1% (2.9% for overnight hospital stay, 2.2% for unplanned post procedure visit to the hospital via the emergency room, or directly to the surgical unit within 30 days of discharge). Age at least 50 years, surgical duration at least 80 min, endoscopic sinus surgery procedures and postoperative nasal packing were identified as negative predictive factors of readmission. CONCLUSION: Careful scheduling of those higher-risk patients undergoing sinonasal surgery and appropriate postoperative observation should be implemented to improve healthcare quality in an outpatient setting.
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Endoscopía/métodos , Senos Paranasales/cirugía , Procedimientos Quirúrgicos Ambulatorios , Hospitalización , Humanos , Complicaciones Posoperatorias , Estudios RetrospectivosRESUMEN
OBJECTIVE: The development and validation of new clinimetric tools is essential for the progress of clinical research in the field of chronic venous insufficiency. Chromametry is a simple, quick and non-invasive technique that measures the color of the skin. The aim of this study was to evaluate the ability of this technique to quantify skin pigmentation as a marker of severity of chronic venous disease and to assess the variability of measurements obtained in this condition. METHODS: Chomametry was performed on three different sites on each lower limb in 42 patients undergoing a spa treatment in La Léchère (Savoie) for chronic venous disorders (CVD). Four series of measurements were taken by two investigators for each patient, at two sessions two to four days apart. RESULTS: The chromameter readily measured the pigmentation index (PI). The PI increased with higher clinical class (CEAP classification) for measurements made at the malleolar level (r=0.48; P<0.001) and the supra-malleolar area (r=0.55; P<0.001), but not at the level of the anterior tibial tuberosity (r=-0.09; P=0.45). The repeatability and the intra- and inter-observer reproducibility of this PI index were 15%, 18% and 21% respectively of the mean of the observed difference at the malleolar level. The chromameter also provided an erythema index, which appears to be less relevant and more variable than the PI, but which might add potentially useful information regarding the characterization of skin inflammation related to the venous disease. CONCLUSION: This study shows that chromametry can be used in clinical research studies to quantify skin changes associated with CVD. Whether it can also be useful for early detection and follow-up of patients with venous trophic changes remains to be investigated.
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Enfermedades Cutáneas Vasculares/etiología , Enfermedades Cutáneas Vasculares/patología , Insuficiencia Venosa/complicaciones , Adulto , Anciano , Anciano de 80 o más Años , Enfermedad Crónica , Color , Técnicas de Diagnóstico Cardiovascular/instrumentación , Femenino , Humanos , Masculino , Persona de Mediana EdadRESUMEN
Broad-band dielectric relaxation measurements were performed for the four pentitols isomers, xylitol, adonitol, L-arabitol and D-arabitol. The comparison of the dynamical properties of these compounds shows similarities between the secondary relaxation processes but also important differences for the temperature dependence of the primary process characterized by the steepness index. These differences enable us to distinguish two groups of compounds that correspond to two kinds of molecular conformation. We show that the formation of more or less extended networks of hydrogen bonds, which reflects the more or less non-Arrhenius variation of the primary relaxation, can be related to the differences of conformation of the studied isomers.
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The present study is part of a global project which consists in the development of an automatic cleaning station for immersed boats (cockle, ninepin, etc.) in a self-service mode, associating an innovative ultrasonic device for cleaning with a specific water treatment. The originality of the process is that cleaning is performed by three transducers operating simultaneously at low frequency and moving along the surface, thanks to programmable logic controllers, and that it includes a suction to collect the dirt removed. Therefore, the time required for boat maintenance is shortened, ensuring high quality cleaning without the need for dry docks and avoiding additional pollution in the harbor areas. One of the key points was the evaluation of washing efficiency, as it is really hard to give a quantitative estimation of the dirt removed. To obtain the first design laws, feasibility tests have been carried out on dirty cockle samples and on real boat hulls with a laboratory ultrasonic device. The influence of a large number of parameters was tested such as transducer-probe distance, displacement speed and transmitted power. The obtained data allowed us to design an optimized cleaning device combining high efficiency and speed.
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Dielectric measurements have been performed on the supercooled plastic crystal phase of cyanoadamantane under isothermal and isochronal conditions in the temperature range [170-250 K], each experiment with a new sample. The measurements performed in the course of isotherms allowed us to emphasize the effects of the transformations close to the glass transition temperature leading to a change in the dynamic behavior of the compound. The temperature dependence of the dielectric relaxation times exhibits an Arrhenius evolution on the whole metastable domain and gives at the calorimetric glass transition temperature a value of 1 s, i.e., two orders of magnitude lower than the usual value [tau(T(g)) congruent with 100 s]. These results indicate that the Vogel-Fulcher-Tammann behavior observed with other techniques does not appear in the Brillouin zone center (q=0) and that the glass transition for this glass former is not associated with the freezing out of the tumbling motion of individual molecular dipoles but to the freezing out of fluctuations of an antiferroelectric local ordering.
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PURPOSE: This study was conducted to characterize the molecular mobility of supercooled fananserine and derive from this analysis the non-Arrhenius and nonexponential properties of the primary alpha-relaxation. METHODS: The use of three investigation techniques of the molecular mobility, namely, dielectric relaxation, modulated differential scanning calorimetry, and proton nuclear magnetic resonance, allowed us to describe the dynamic properties of supercooled fananserine on a wide range of frequencies and temperatures, ranging from the melting temperature T(m) = 372 K down to the glass transition temperature T(g) = 292 K. RESULTS: We emphasized the capacity of these three techniques to give a coherent set of information. We used the coupling-model theory to interpret the dielectric results. It allowed us to identify two relaxation processes (alpha and beta), corresponding to different molecular motions. The temperature evolution of the alpha-relaxation indicates that fananserine is a fragile glass former, as reflected by the steepness index value, m = 77. The temperature T(o) where the relaxation times diverge was also determined. CONCLUSIONS: The description of the dielectric relaxation data in terms of the Kohlrausch-Williams-Watt relaxation function has shown the existence of an additional low-amplitude relaxation process assigned to the so-called Johari-Goldstein process. Mainly concerned by the primary alpha-process directly involved in the glass formation, we derived from this analysis the characteristic features of this process and showed that supercooled fananserine is characterized by a strongly non-Arrhenius and nonexponential behavior.
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Óxidos S-Cíclicos/química , Naftalenos/química , Presión del Aire , Algoritmos , Rastreo Diferencial de Calorimetría , Fenómenos Químicos , Química Física , Cristalización , Concentración de Iones de Hidrógeno , Isomerismo , Espectroscopía de Resonancia Magnética , Conformación Molecular , Temperatura , Termodinámica , Difracción de Rayos XRESUMEN
Crystallization processes in indomethacin can be observed below Tg leading to different forms depending on the thermal treatment: a rapid and deep quench below Tg leads to the metastable alpha-phase and a slow cooling close to Tg gives rise to the stable gamma-phase. To understand this atypical behavior, we have studied the molecular mobility of the amorphous and crystalline forms of indomethacin by dielectric relaxation and 1H NMR spectroscopy. Two relaxations were detected in the glassy state obtained from the deeply quenched liquid. One, also present in the gamma-phase, was attributed to local rotations. The other one, of very low amplitude, was attributed to the Johari-Goldstein relaxation. The results allowed to discuss the relationship between these two relaxation processes and the crystallization properties of amorphous indomethacin.
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Indometacina/química , Cristalización , Espectroscopía de Resonancia Magnética/métodos , Estructura Molecular , Sensibilidad y Especificidad , Estereoisomerismo , TemperaturaRESUMEN
The dynamic properties of plastic crystalline mixed adamantane's derivatives namely cyanoadamantane (75%) and chloroadamantane (25%) were investigated by dielectric and nuclear magnetic resonance (NMR) spectroscopy, covering a spectral range of 12 decades in the temperature range 110-420 K. Phase transformations were studied and dynamical parameters of the plastic (I), glassy (Ig), and ordered (III) phases were determined and compared with those of pure compounds. The dynamics of the supercooled plastic phase is characterized by an alpha-process exhibiting an Arrhenius behavior which classified the mixed compound as a strong glass former. In the plastic phase, NMR relaxation times were interpreted by using a Frenkel model, which takes into account structural equilibrium positions. This model explains adequately the experimental results by considering two molecular motions. In both the glassy state and plastic phase the motional parameters agree with those of 1-cyanoadamantane. On the contrary, in the ordered phase, the motional parameters related to the uniaxial rotation of chloroadamantane molecules indicate an accelerated motion.
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The dynamics in supercooled meta-toluidine was studied using dielectric relaxation, modulated differential scanning calorimetry, proton spin-lattice relaxation times, and viscosity measurements. The combination of these different techniques has clearly shown a large decoupling of the relaxation modes whose origin is attributed to the formation of clusters via the NH2 bonding. This decoupling starts at a temperature also corresponding to a change of the dynamical behavior from a high temperature Arrhenius evolution to a Vogel-Fulcher-Tamman low temperature evolution.
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BACKGROUND: Remifentanil and alfentanil are opioids often used during direct laryngoscopy (DL). This prospective, randomized study compared these agents with respect to haemodynamic and Bispectral Index (BIS) responses, glottic visualization, and rapidity of recovery (spontaneous ventilation, eye opening) in DL without intubation. METHODS: A total of 60 patients undergoing DL were randomized into two groups: remifentanil (R) and alfentanil (A). Anaesthesia was induced with propofol 2.5 mg kg(-1) and the opioid was administered 1 min later (R=2 microg kg(-1) or A=30 microg kg(-1) over 30 s). DL was commenced 1 min after (corresponding to 3 min after the beginning of induction). Glottic visualization, opioid and/or propofol re-injection, spontaneous ventilation recovery, and eye opening were recorded. RESULTS: During DL, mean arterial pressure (MAP) increased by 6% in the R group vs 20% in the A group (P<0.05) when compared with post-induction values without affecting heart rate or BIS. No significant difference was observed between groups with respect to glottic exposure, opioid and/or propofol re-injection, and spontaneous ventilation recovery (mean (SEM) 3.8 (0.6) min, R group vs 3.2 (0.7) min, A group, NS) or eye opening (7.1 (1.1) min, R group vs 7.4 (0.9) min, A group, NS). Thirty minutes after postanaesthesia care unit (PACU) admission, MAP returned to its pre-induction value in the R group (104 (3) vs 109 (3) at baseline, NS), whereas in the A group MAP remained significantly lower at this time point (96 (4) vs 106 (3) at baseline, P<0.05). CONCLUSION: This study showed that only remifentanil prevented MAP increase without adverse effects such as bradycardia during DL, and prevented MAP decrease 30 min after PACU admission.
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Alfentanilo , Analgésicos Opioides , Laringoscopía , Piperidinas , Adulto , Periodo de Recuperación de la Anestesia , Anestesia Intravenosa , Presión Sanguínea/efectos de los fármacos , Electroencefalografía/efectos de los fármacos , Femenino , Frecuencia Cardíaca/efectos de los fármacos , Humanos , Masculino , Estudios Prospectivos , RemifentaniloRESUMEN
We report the case of a 64-year-old man without hemorrhagic history experiencing epistaxis. The standard hemostasis assessment including prothrombin index, activated partial thromboplastin time (APTT) and platelet count found an isolated abnormal APTT (105 sec vs 33 sec). Therefore, coagulation factors were explored. An acquired factor VIII deficiency (5%) with anti-FVIII antibody (4.5 Bethesda unit.mL-1) was recognised. This anti-FVIII antibody was related to a Chlamydia pneumoniae pulmonary infection. Treatment consisted of: i) Four successive anterior packing and activated factor VII infusion (Novoseven); ii) steroids injection and bi-antibiotherapy. The time course of the epistaxis was favourable under treatment.
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Autoanticuerpos/inmunología , Infecciones por Chlamydia/inmunología , Chlamydophila pneumoniae/inmunología , Factor VIII/inmunología , Antiinflamatorios/uso terapéutico , Pruebas de Coagulación Sanguínea , Epistaxis/complicaciones , Epistaxis/tratamiento farmacológico , Factor VIII/uso terapéutico , Humanos , Masculino , Persona de Mediana Edad , EsteroidesRESUMEN
To determine whether Epstein-Barr virus (EBV) constitutes a contributing factor in AIDS and, conversely, whether the human immunodeficiency virus (HIV) alters the course of primary EBV infection in a pediatric population, 62 children born to HIV-infected mothers and prospectively followed were evaluated. EBV infection was documented by EBV-specific serology and polymerase chain reaction and by clinical history. HIV infection status was determined according to the Centers for Disease Control and Prevention pediatric classification system. Demographics from HIV-infected and HIV-uninfected children were comparable. The data suggest that HIV-infected children may acquire primary EBV infection earlier in life. The incidence of accompanying splenomegaly or hepatomegaly (or both) around the time of EBV seroconversion was higher among HIV-infected children than among HIV-uninfected children. In contrast, HIV disease progression and HIV-1 RNA load did not seem to be influenced by primary EBV infection.
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Infecciones Oportunistas Relacionadas con el SIDA/epidemiología , Infecciones por Herpesviridae/epidemiología , Infecciones Tumorales por Virus/epidemiología , Infecciones Oportunistas Relacionadas con el SIDA/virología , Anticuerpos Antivirales/análisis , Anticuerpos Antivirales/inmunología , Cápside/inmunología , ADN Viral/genética , ADN Viral/aislamiento & purificación , Femenino , VIH-1/genética , VIH-1/inmunología , VIH-1/aislamiento & purificación , Hepatomegalia/diagnóstico , Hepatomegalia/epidemiología , Infecciones por Herpesviridae/diagnóstico , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/inmunología , Herpesvirus Humano 4/aislamiento & purificación , Humanos , Incidencia , Lactante , Recién Nacido , Masculino , Reacción en Cadena de la Polimerasa , Embarazo , Complicaciones Infecciosas del Embarazo/virología , Estudios Prospectivos , ARN Viral/aislamiento & purificación , Esplenomegalia/diagnóstico , Esplenomegalia/epidemiología , Infecciones Tumorales por Virus/diagnóstico , Carga ViralRESUMEN
A variety of antibody response patterns to the latent Epstein-Barr nuclear antigen (EBNA) family have been described in different groups of subjects infected with Epstein-Barr virus (EBV). The purpose of this study was to characterize the immune response to two EBNA proteins, EBNA-1 and EBNA-2, in a population of children who were born to mothers infected with HIV and who underwent EBV seroconversion. Serial serum specimens from 33 children (nine were infected with HIV, and 24 were not infected) were evaluated for the presence of antibodies to EBNA-1 and EBNA-2 by anticomplement immunofluorescence. All the EBNA serology profiles observed for children in our study who were not infected with HIV were consistent with those described for immunocompetent hosts with acute EBV infection, i.e., development of antibodies to EBNA-1, often preceded by the appearance of a humoral immune response to EBNA-2. In contrast, following EBV primary infection in HIV-infected children, antibodies to EBNA-2 arose after antibodies to EBNA-1 and tended to persist. Further studies are needed to investigate the role of EBNA-2 serology as a prognostic marker in HIV-infected children.
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Anticuerpos Antivirales/análisis , Antígenos Nucleares del Virus de Epstein-Barr/inmunología , Infecciones por VIH/complicaciones , Infecciones por VIH/virología , Infecciones por Herpesviridae/complicaciones , Infecciones por Herpesviridae/inmunología , Infecciones Tumorales por Virus/complicaciones , Infecciones Tumorales por Virus/inmunología , Femenino , Técnica del Anticuerpo Fluorescente Directa , Infecciones por VIH/sangre , Infecciones por Herpesviridae/sangre , Humanos , Recién Nacido , Transmisión Vertical de Enfermedad Infecciosa , Embarazo , Complicaciones Infecciosas del Embarazo/inmunología , Complicaciones Infecciosas del Embarazo/virología , Pruebas Serológicas , Infecciones Tumorales por Virus/sangreRESUMEN
A previous study (Savoie et al, Blood 83:2715, 1994) identified eight transplant patients who acquired Epstein-Barr virus (EBV) infection during the peritransplant period. Three of these patients subsequently developed B-cell lymphoproliferative disease within 4 months of transplantation. Among these, there was a 16-year-old liver transplant patient who was negative for EBV at the time of transplant and who received an EBV-negative organ. After transplant, this patient was transfused with 9 U of packed red blood cells. Eight of the donors were EBV-positive and one was EBV-negative. We succeeded in obtaining spontaneous lymphoblastoid cell lines (LCLs) from the blood of three of these donors, one of whom also yielded a cord-blood line established with his throat-wash EBV. Blood from a fourth donor did not yield an LCL, but his throat washing did have transforming activity when inoculated onto cord-blood leukocytes. We initially could establish spontaneous LCLs only from the recipient's blood. However, a throat-wash sample taken 11 weeks later did show transforming activity. The recipient was shown to have acquired the EBV infection from one of eight EBV-seropositive blood donors. Analysis of fragment length polymorphisms after polymerase chain reaction amplification of the EBV BamHI-K fragment was used to establish strain identity. Western blot analysis for existence of size polymorphisms in three classes of Epstein-Barr nuclear antigens (EBNA-1, EBNA-2, and EBNA-3) confirmed the DNA results. It is noteworthy that the blood donor responsible for transmitting his EBV strain to the recipient had experienced clinical infectious mononucleosis 15 months before donating blood. Our results may, thus, indicate a requirement for leukodepletion of blood destined for immunosuppressed EBV-negative patients. Finally, blood donors with a recent history of infectious mononucleosis should probably be identified so that their blood is not given to EBV-negative transplant patients.
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Donantes de Sangre , Infecciones por Herpesviridae/transmisión , Herpesvirus Humano 4 , Trasplante de Hígado , Orofaringe/virología , Complicaciones Posoperatorias/virología , Reacción a la Transfusión , Infecciones Tumorales por Virus/transmisión , Viremia/virología , Adolescente , Antígenos Virales/genética , Antígenos Virales/aislamiento & purificación , Trazado de Contacto , ADN Viral/genética , ADN Viral/aislamiento & purificación , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/aislamiento & purificación , Antígenos Nucleares del Virus de Epstein-Barr , Femenino , Enfermedad del Almacenamiento de Glucógeno Tipo I/cirugía , Infecciones por Herpesviridae/virología , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/aislamiento & purificación , Humanos , Polimorfismo Genético , Saliva/virología , Infecciones Tumorales por Virus/virología , Activación ViralRESUMEN
A recent survey shows that patients turn to modern medicine more than traditional medicine for most of their needs except rheumatic and neurological complaints. However, the preferences stated are influenced on the one hand by the much lower cost of traditional services, and on the other by official disapproval of animistic practices.