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1.
For Policy Econ ; 111: 102032, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32140044

RESUMEN

The quantification of forests available for wood supply (FAWS) is essential for decision-making with regard to the maintenance and enhancement of forest resources and their contribution to the global carbon cycle. The provision of harmonized forest statistics is necessary for the development of forest associated policies and to support decision-making. Based on the National Forest Inventory (NFI) data from 13 European countries, we quantify and compare the areas and aboveground dry biomass (AGB) of FAWS and forest not available for wood supply (FNAWS) according to national and reference definitions by determining the restrictions and associated thresholds considered at country level to classify forests as FAWS or FNAWS. FAWS represent between 75 and 95 % of forest area and AGB for most of the countries in this study. Economic restrictions are the main factor limiting the availability of forests for wood supply, accounting for 67 % of the total FNAWS area and 56 % of the total FNAWS AGB, followed by environmental restrictions. Profitability, slope and accessibility as economic restrictions, and protected areas as environmental restrictions are the factors most frequently considered to distinguish between FAWS and FNAWS. With respect to the area of FNAWS associated with each type of restriction, an overlap among the restrictions of 13.7 % was identified. For most countries, the differences in the FNAWS areas and AGB estimates between national and reference definitions ranged from 0 to 5 %. These results highlight the applicability and reliability of a FAWS reference definition for most of the European countries studied, thereby facilitating a consistent approach to assess forests available for supply for the purpose of international reporting.

2.
Environ Sci Technol ; 50(5): 2200-9, 2016 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-26811969

RESUMEN

We present measurements as part of the Southern Oxidant and Aerosol Study (SOAS) during which atmospheric aerosol particles were comprehensively characterized. We present results utilizing a Filter Inlet for Gases and AEROsol coupled to a chemical ionization mass spectrometer (CIMS). We focus on the volatility and composition of isoprene derived organic aerosol tracers and of the bulk organic aerosol. By utilizing the online volatility and molecular composition information provided by the FIGAERO-CIMS, we show that the vast majority of commonly reported molecular tracers of isoprene epoxydiol (IEPOX) derived secondary organic aerosol (SOA) is derived from thermal decomposition of accretion products or other low volatility organics having effective saturation vapor concentrations <10(-3) µg m(-3). In addition, while accounting for up to 30% of total submicrometer organic aerosol mass, the IEPOX-derived SOA has a higher volatility than the remaining bulk. That IEPOX-SOA, and more generally bulk organic aerosol in the Southeastern U.S. is comprised of effectively nonvolatile material has important implications for modeling SOA derived from isoprene, and for mechanistic interpretations of molecular tracer measurements. Our results show that partitioning theory performs well for 2-methyltetrols, once accretion product decomposition is taken into account. No significant partitioning delays due to aerosol phase or viscosity are observed, and no partitioning to particle-phase water or other unexplained mechanisms are needed to explain our results.


Asunto(s)
Aerosoles/química , Monitoreo del Ambiente/métodos , Aerosoles/análisis , Atmósfera/química , Butadienos/química , Gases , Hemiterpenos/química , Espectrometría de Masas/métodos , Pentanos/química , Sudeste de Estados Unidos , Volatilización
3.
J Mol Cell Cardiol ; 56: 8-18, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23291429

RESUMEN

In human atrial myocytes the transient outward current I(to) develops a conspicuous faster inactivation with increasing temperatures. Since ß-subunits are known to modulate I(to) current kinetics, we hypothesized that the temperature sensitivity of I(to) is not only determined by the property of the ion-passing α-subunit Kv4.3 but also by its interaction with accessory ß-subunits. We therefore studied the influence of the transmembrane ß-subunits KCNE1, KCNE2 and DPP6 on Kv4.3/KChIP2 channels in CHO cells at room temperature and at physiological temperature. Exposure to 37°C caused a significant acceleration of the channel kinetics, whereas current densities and voltage dependences remained unaltered at 37°C compared to 23°C. However, Kv4.3/KChIP2 channels without transmembrane ß-subunits showed the strongest temperature sensitivity with considerably increased rates of activation and inactivation at 37°C. KCNE2 significantly slowed the current kinetics at 37°C compared to Kv4.3/KChIP2 channels, whereas KCNE1 did not influence the channel properties at both temperatures. Interestingly, the accelerating effects of DPP6 on current kinetics described at 23°C were diminished at physiological temperature, thus at 37°C current kinetics became remarkably similar for channel complexes Kv4.3/KChIP2 with and without DPP6 isoforms. A Markov state model was developed on the basis of experimental measurements to simulate the influence of ß-subunits on Kv4.3 channel complex at both temperatures. In conclusion, the remarkably fast kinetics of the native I(to) at 37°C could be reproduced by co-expressing Kv4.3, KChIP2, KCNE2 and DPP6 in CHO cells, whereas the high temperature sensitivity of human I(to) could be not mimicked.


Asunto(s)
Subunidades de Proteína/fisiología , Canales de Potasio Shal/metabolismo , Potenciales de Acción , Animales , Células CHO , Cricetinae , Dipeptidil-Peptidasas y Tripeptidil-Peptidasas/fisiología , Humanos , Activación del Canal Iónico , Cinética , Cadenas de Markov , Modelos Biológicos , Proteínas del Tejido Nervioso/fisiología , Técnicas de Placa-Clamp , Canales de Potasio/fisiología , Canales de Potasio con Entrada de Voltaje/fisiología , Estabilidad Proteica , Termodinámica
4.
Eur Respir J ; 37(5): 1208-16, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21109556

RESUMEN

Despite association with lung growth and long-term respiratory morbidity, there is a lack of normative lung function data for unsedated infants conforming to latest European Respiratory Society/American Thoracic Society standards. Lung function was measured using an ultrasonic flow meter in 342 unsedated, healthy, term-born infants at a mean ± sd age of 5.1 ± 0.8 weeks during natural sleep according to the latest standards. Tidal breathing flow-volume loops (TBFVL) and exhaled nitric oxide (eNO) measurements were obtained from 100 regular breaths. We aimed for three acceptable measurements for multiple-breath washout and 5-10 acceptable interruption resistance (R(int)) measurements. Acceptable measurements were obtained in ≤ 285 infants with high variability. Mean values were 7.48 mL·kg⁻¹ (95% limits of agreement 4.95-10.0 mL·kg⁻¹) for tidal volume, 14.3 ppb (2.6-26.1 ppb) for eNO, 23.9 mL·kg⁻¹ (16.0-31.8 mL·kg⁻¹) for functional residual capacity, 6.75 (5.63-7.87) for lung clearance index and 3.78 kPa·s·L⁻¹ (1.14-6.42 kPa·s·L⁻¹) for R(int). In males, TBFVL outcomes were associated with anthropometric parameters and in females, with maternal smoking during pregnancy, maternal asthma and Caesarean section. This large normative data set in unsedated infants offers reference values for future research and particularly for studies where sedation may put infants at risk. Furthermore, it highlights the impact of maternal and environmental risk factors on neonatal lung function.


Asunto(s)
Pulmón/fisiología , Óxido Nítrico/normas , Pruebas Respiratorias , Estudios de Cohortes , Femenino , Humanos , Lactante , Masculino , Estudios Prospectivos , Valores de Referencia , Sueño , Fumar/efectos adversos
5.
Eur J Med Res ; 16(5): 223-30, 2011 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-21719396

RESUMEN

OBJECTIVE: While respiratory symptoms in the first year of life are relatively well described for term infants, data for preterm infants are scarce. We aimed to describe the burden of respiratory disease in a group of preterm infants with and without bronchopulmonary dysplasia (BPD) and to assess the association of respiratory symptoms with perinatal, genetic and environmental risk factors. METHODS: Single centre birth cohort study: prospective recording of perinatal risk factors and retrospective assessment of respiratory symptoms during the first year of life by standardised questionnaires. MAIN OUTCOME MEASURES: Cough and wheeze (common symptoms), re-hospitalisation and need for inhalation therapy (severe outcomes). PATIENTS: 126 preterms (median gestational age 28.7 weeks; 78 with, 48 without BPD) hospitalised at the University Children's Hospital of Bern, Switzerland 1999-2006. RESULTS: Cough occurred in 80%, wheeze in 44%, re-hospitalisation in 25% and long term inhalation therapy in wheezers in 13% of the preterm infants. Using logistic regression, the main risk factor for common symptoms was frequent contact with other children. Severe outcomes were associated with maximal peak inspiratory pressure, arterial cord blood pH, APGAR- and CRIB-Score. CONCLUSIONS: Cough in preterm infants is as common as in term infants, whereas wheeze, inhalation therapy and re-hospitalisations occur more often. Severe outcomes are associated with perinatal risk factors. Preterm infants who did not qualify for BPD according to latest guidelines also showed a significant burden of respiratory disease in the first year of life.


Asunto(s)
Displasia Broncopulmonar/complicaciones , Enfermedades del Prematuro/etiología , Trastornos Respiratorios/etiología , Tos/etiología , Femenino , Humanos , Lactante , Recién Nacido , Recien Nacido Prematuro , Modelos Logísticos , Masculino , Morbilidad , Ruidos Respiratorios/etiología , Factores de Riesgo
6.
Vasa ; 37(1): 81-5, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18512545

RESUMEN

BACKGROUND: To evaluate whether dedicated access surgeons might have a significantly higher risk of acquiring hepatitis C infection compared to other vascular surgeons by assessing the prevalence of hepatitis C patients who are on chronic hemodialysis and to compare the frequency to patients undergoing elective vascular interventions. PATIENTS AND METHODS: A retrospective chart and data analysis of all patients on chronic hemodialysis was conducted. As a comparative group, the prevalence of anti-HCV antibodies and positive HCV RNA PCR among patients admitted for elective vascular surgery was assessed. RESULTS: Of 285 patients on chronic hemodialysis, 202 (71%) were had both tests (antibody test for HCV and specific HCV RNA PCR testing). 5% (n = 11; CI 95 = 3-10%) were antibody positive, and 4% (n = 8; CI 95 = 2-8%) were also PCR positive and therefore infectious. One patient was acutely infected. Of 4963 vascular surgical patients, 1141 (23%) had an anti-HCV antibody ELISA test and specific HCV RNA PCR testing. 0.4% (n = 4; CI 95 = 0.1-1%) were antibody positive and 0.2% (n = 2; CI 95 = 0.03-0.7%) were also PCR positive and hence infectious. No acutely infected patient was detected in this population. The chance of operating on a HCV positive and infectious patient among hemodialysis patients was almost 27 times higher than among elective vascular surgical patients (P < 0.0001; OR = 26.56; CI 95 = 5.42-253.40). CONCLUSIONS: Dedicated hemodialysis access surgeons have a higher risk to acquire hepatitis C infection compared to vascular surgeons performing all other elective vascular surgical interventions. To identify early infected surgeons operating on high risk HCV patient collectives and to start rapid treatment, PCR testing at regular intervals would be advisable.


Asunto(s)
Derivación Arteriovenosa Quirúrgica/efectos adversos , Hepatitis C/transmisión , Transmisión de Enfermedad Infecciosa de Paciente a Profesional , Enfermedades Renales/terapia , Diálisis Renal , Procedimientos Quirúrgicos Vasculares/efectos adversos , Adulto , Anciano , Anciano de 80 o más Años , Procedimientos Quirúrgicos Electivos , Ensayo de Inmunoadsorción Enzimática , Femenino , Hepacivirus/genética , Hepacivirus/inmunología , Hepatitis C/complicaciones , Hepatitis C/diagnóstico , Hepatitis C/cirugía , Anticuerpos contra la Hepatitis C/sangre , Humanos , Enfermedades Renales/complicaciones , Enfermedades Renales/cirugía , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Reacción en Cadena de la Polimerasa , ARN Viral/sangre , Estudios Retrospectivos , Medición de Riesgo , Recursos Humanos
7.
Physiol Res ; 67(Suppl 2): S367-S375, 2018 10 30.
Artículo en Inglés | MEDLINE | ID: mdl-30379557

RESUMEN

Early diagnosis of ongoing malignant disease is crucial to improve survival rate and life quality of the patients and requires sensitive detection of specific biomarkers e.g. prostate-specific antigen (PSA), carcinoembryonic antigen (CEA), alpha-fetoprotein (AFP), etc. In spite of current technological advances, malignant diseases are still identified in rather late stages, which have detrimental effect on the prognosis and treatment of the disease. Here, we present a biosensor able to detect fetuin-A, a potential multibiomarker. The biosensing platform is based on polymer brush combining antifouling monomer units of N-(2-hydroxypropyl)methacrylamide (HPMA) and carboxybetaine methacrylamide (CBMAA), statistically copolymerized by surfaceinitiated atom transfer radical polymerization. The copolymer poly(HPMA-co-CBMAA) exhibits excellent non-fouling properties in the most relevant biological media (i.e. blood plasma) as well as antithrombogenic surface properties by preventing the adhesion of blood components (i.e. leukocytes; platelets; and erythrocytes). Moreover, the polymer brush can be easily functionalized with biorecognition elements maintaining high resistance to blood fouling and the binding capacity can be regulated by tuning the ratio between CBMAA and HPMA units. The superior antifouling properties of the copolymer even after biofunctionalization were exploited to fabricate a new plasmonic biosensor for the analysis of fetuin-A in real clinical blood plasma samples. The assay used in this work can be explored as labelfree affinity biosensor for diagnostics of different biomarkers in real clinical plasma samples and to shift the early biomarker detection toward novel biosensor technologies allowing point of care analysis.


Asunto(s)
Técnicas Biosensibles/métodos , Resonancia por Plasmón de Superficie/métodos , alfa-2-Glicoproteína-HS/análisis , alfa-2-Glicoproteína-HS/metabolismo , Biomarcadores/sangre , Humanos
8.
Pediatr Pulmonol ; 42(10): 920-7, 2007 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17722053

RESUMEN

BACKGROUND: Estimation of respiratory deadspace is often based on the CO2 expirogram, however presence of the CO2 sensor increases equipment deadspace, which in turn influences breathing pattern and calculation of lung volume. In addition, it is necessary to correct for the delay between the sensor and flow signals. We propose a new method for estimation of effective deadspace using the molar mass (MM) signal from an ultrasonic flowmeter device, which does not require delay correction. We hypothesize that this estimation is correlated with that calculated from the CO2 signal using the Fowler method. METHODS: Breath-by-breath CO2, MM and flow measurements were made in a group of 77 term-born healthy infants. Fowler deadspace (Vd,Fowler) was calculated after correcting for the flow-dependent delay in the CO2 signal. Deadspace estimated from the MM signal (Vd,MM) was defined as the volume passing through the flowhead between start of expiration and the 10% rise point in MM. RESULTS: Correlation (r = 0.456, P < 0.0001) was found between Vd,MM and Vd,Fowler averaged over all measurements, with a mean difference of -1.4% (95% CI -4.1 to 1.3%). Vd,MM ranged from 6.6 to 11.4 ml between subjects, while Vd,Fowler ranged from 5.9 to 12.0 ml. Mean intra-measurement CV over 5-10 breaths was 7.8 +/- 5.6% for Vd,MM and 7.8 +/- 3.7% for Vd,Fowler. Mean intra-subject CV was 6.0 +/- 4.5% for Vd,MM and 8.3 +/- 5.9% for Vd,Fowler. Correcting for the CO2 signal delay resulted in a 12% difference (P = 0.022) in Vd,Fowler. Vd,MM could be obtained more frequently than Vd,Fowler in infants with CLD, with a high variability. CONCLUSIONS: Use of the MM signal provides a feasible estimate of Fowler deadspace without introducing additional equipment deadspace. The simple calculation without need for delay correction makes individual adjustment for deadspace in FRC measurements possible. This is especially important given the relative large range of deadspace seen in this homogeneous group of infants.


Asunto(s)
Dióxido de Carbono/metabolismo , Flujómetros , Mediciones del Volumen Pulmonar/instrumentación , Espacio Muerto Respiratorio/fisiología , Ultrasonografía/instrumentación , Femenino , Humanos , Lactante , Recién Nacido , Mediciones del Volumen Pulmonar/métodos , Masculino , Ultrasonografía/métodos
9.
Pediatr Pulmonol ; 42(10): 888-97, 2007 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17726709

RESUMEN

BACKGROUND: Assessment of lung volume (FRC) and ventilation inhomogeneities with ultrasonic flowmeter and multiple breath washout (MBW) has been used to provide important information about lung disease in infants. Sub-optimal adjustment of the mainstream molar mass (MM) signal for temperature and external deadspace may lead to analysis errors in infants with critically small tidal volume changes during breathing. METHODS: We measured expiratory temperature in human infants at 5 weeks of age and examined the influence of temperature and deadspace changes on FRC results with computer simulation modeling. A new analysis method with optimized temperature and deadspace settings was then derived, tested for robustness to analysis errors and compared with the previously used analysis methods. RESULTS: Temperature in the facemask was higher and variations of deadspace volumes larger than previously assumed. Both showed considerable impact upon FRC and LCI results with high variability when obtained with the previously used analysis model. Using the measured temperature we optimized model parameters and tested a newly derived analysis method, which was found to be more robust to variations in deadspace. Comparison between both analysis methods showed systematic differences and a wide scatter. CONCLUSION: Corrected deadspace and more realistic temperature assumptions improved the stability of the analysis of MM measurements obtained by ultrasonic flowmeter in infants. This new analysis method using the only currently available commercial ultrasonic flowmeter in infants may help to improve stability of the analysis and further facilitate assessment of lung volume and ventilation inhomogeneities in infants.


Asunto(s)
Flujómetros , Capacidad Residual Funcional/fisiología , Ultrasonografía/métodos , Simulación por Computador , Femenino , Flujómetros/normas , Humanos , Lactante , Recién Nacido , Masculino , Modelos Biológicos , Espacio Muerto Respiratorio , Temperatura
10.
Physiol Res ; 65(Suppl 2): S253-S261, 2016 10 20.
Artículo en Inglés | MEDLINE | ID: mdl-27762591

RESUMEN

Understanding the behavior of single proteins at the polyelectrolyte multilayer film/solution interface is of prime importance for the designing of bio-functionalized surface coatings. In the present paper, we study the adsorption of the model proteins, albumin and lysozyme, as well as basic fibroblast growth factor (FGF-2) on a polysaccharide multilayer film composed of quaternized chitosan and heparin. Several analytical methods were used to describe the formation of the polysaccharide film and its interactions with the proteins. Both albumin and lysozyme adsorbed on quaternized chitosan/heparin films, however this process strongly depended on the terminating polysaccharide. Protein adsorption was driven mainly by electrostatic interactions between protein and the terminal layer of the film. The effective binding of FGF-2 by the heparin-terminated film suggested that other interactions could also contribute to the adsorption process. We believe that this FGF-2-presenting polysaccharide film may serve as a biofunctional surface coating for biologically-related applications.


Asunto(s)
Quitosano/química , Materiales Biocompatibles Revestidos , Heparina/química , Proteínas/química , Adsorción
11.
Physiol Res ; 65(Suppl 2): S263-S272, 2016 10 20.
Artículo en Inglés | MEDLINE | ID: mdl-27762592

RESUMEN

Fibrin is a versatile biopolymer that has been extensively used in tissue engineering. In this paper fibrin nanostructures prepared using a technique based on the catalytic effect of fibrin-bound thrombin are presented. This technique enables surface-attached thin fibrin networks to form with precisely regulated morphology without the development of fibrin gel in bulk solution. Moreover, the influence of changing the polymerization time, along with the antithrombin III and heparin concentrations on the morphology of fibrin nanostructures was explored. The binding of bioactive molecules (fibronectin, laminin, collagen, VEGF, bFGF, and heparin) to fibrin nanostructures was confirmed. These nanostructures can be used for the surface modification of artificial biomaterials designed for different biomedical applications (e.g. artificial vessels, stents, heart valves, bone and cartilage constructs, skin grafts, etc.) in order to promote the therapeutic outcome.


Asunto(s)
Materiales Biocompatibles , Fibrina/química , Nanoestructuras/química , Adsorción , Antitrombina III , Fibrinógeno/química , Heparina , Polimerizacion , Trombina/química
12.
Transplantation ; 70(8): 1174-80, 2000 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-11063336

RESUMEN

BACKGROUND: Although specific therapy is available with ganciclovir, cytomegalovirus (CMV) disease remains a major problem after renal transplantation especially in CMV seronegative recipients of organs of seropositive donors (D+R-). METHODS: In an open-labeled prospective controlled trial we evaluated the effect of long-term oral ganciclovir prophylaxis (3 g/day for 3 months posttransplantation) in a cohort of 31 CMV-high risk (D+R-) renal transplant recipients (GC) compared with a cohort of 28 high-risk patients with targeted CMV prophylaxis (CO) receiving i.v. ganciclovir during antirejection therapy. Primary end-points were CMV infection, diagnosed by pp65 antigenemia assay or serologic method, and CMV disease. Additionally severity of CMV disease quantified by a scoring system was evaluated. RESULTS: CMV prophylaxis significantly reduced the incidence of CMV infection (CO: 75%, GC: 45%; P<.05) and CMV disease (CO: 60%, GC: 29%; P<.05) without relevant side effects and without any clinical suspicion of ganciclovir resistance. Severity of CMV disease as quantified by a scoring system was reduced from 8.3+/-6.7 points in controls to 3.3+/-2.6 points in ganciclovir-treated patients (P<.05). Mortality did not differ significantly between the two groups (CO: n=3, GC: n=1; NS). However, there was one lethal CMV disease and a second death possibly attributable to CMV disease in the control group, whereas in ganciclovir-treated patients there was no CMV-associated fatal outcome. CONCLUSION: Long-term oral ganciclovir prophylaxis is effective and safe in CMV high-risk renal transplant recipients.


Asunto(s)
Antivirales/administración & dosificación , Infecciones por Citomegalovirus/prevención & control , Ganciclovir/administración & dosificación , Trasplante de Riñón , Administración Oral , Adulto , Infecciones por Citomegalovirus/epidemiología , Infecciones por Citomegalovirus/mortalidad , Femenino , Rechazo de Injerto/prevención & control , Humanos , Inmunosupresores/uso terapéutico , Trasplante de Riñón/inmunología , Masculino , Persona de Mediana Edad , Factores de Riesgo , Tasa de Supervivencia , Factores de Tiempo
13.
Bone Marrow Transplant ; 28(8): 765-8, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11781628

RESUMEN

We prospectively monitored 74 consecutive allogeneic and 50 autologous patients after bone marrow/stem cell transplantation from May 1999 to October 2000 at our institution with quantitative CMV PCR and pp65 antigen assay once weekly from conditioning therapy to days 120 and 80 after transplantation, respectively. Written informed consent was obtained from every patient. CMV prophylaxis consisted of acyclovir during transplant. Additionally all patients received only platelet products from CMV-negative donors. In the case of CMV infection preemptive therapy with gancyclovir was applied. In the case of CMV disease high-dose immunoglobulin was given as well. In the allogeneic setting 16 out of 74 (22%) patients developed a positive PCR. Seven episodes of a positive pp65 antigen assay occurred in six allograft recipients. In the autologous setting no positive assay was found during the whole observation period. Additionally, in 6/16 patients a lymphoproliferative assay was performed during CMV infection. Two patients showed a positive (15 and 5.4) and four a negative (2,1.6,1,1.8) stimulation index.


Asunto(s)
Antígenos Virales/sangre , Trasplante de Médula Ósea , Infecciones por Citomegalovirus/diagnóstico , Citomegalovirus/aislamiento & purificación , ADN Viral/sangre , Trasplante de Células Madre Hematopoyéticas , Fosfoproteínas/sangre , Reacción en Cadena de la Polimerasa/métodos , Proteínas de la Matriz Viral/sangre , Viremia/diagnóstico , Adolescente , Adulto , Antivirales/uso terapéutico , Biomarcadores , Trasplante de Médula Ósea/mortalidad , Infecciones por Citomegalovirus/sangre , Infecciones por Citomegalovirus/tratamiento farmacológico , Infecciones por Citomegalovirus/etiología , Infecciones por Citomegalovirus/mortalidad , Infecciones por Citomegalovirus/prevención & control , Femenino , Ganciclovir/uso terapéutico , Trasplante de Células Madre Hematopoyéticas/mortalidad , Humanos , Huésped Inmunocomprometido , Recuento de Linfocitos , Masculino , Persona de Mediana Edad , Tasa de Supervivencia , Trasplante Autólogo , Trasplante Homólogo , Resultado del Tratamiento , Viremia/sangre , Viremia/etiología
14.
J Am Geriatr Soc ; 45(11): 1352-9, 1997 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9361661

RESUMEN

OBJECTIVE: To present and evaluate an instrument, the Telephone Cognitive Assessment Battery (TCAB), designed to be administered over the telephone to assess the cognitive status of older individuals. The TCAB addresses mental status, reasoning and executive ability, primary and secondary memory, and language. It consists of six neuropsychological tests and takes approximately 15 to 20 minutes to complete. DESIGN: The instrument is evaluated with a comparative cross-sectional design, with data collected both prospectively and retrospectively. SETTING: The University Hospitals of Cleveland/Case Western Reserve University Alzheimer Center Research Registry. PARTICIPANTS: Forty Alzheimer's Disease cases selected from among those most recently recruited into the Registry and 40 cognitively intact Registry controls. Controls were selected randomly so that the two groups had similar distributions of age, sex, and education. MEASUREMENTS: The cognitive status of all participants was assessed utilizing both the TCAB and the usual in-person Registry evaluation, which includes medical history data and in-person assessment of cognitive status. In order to measure the potential learning effect of repeated testing, half of the cases and half of the controls were recruited and assessed over the telephone with the TCAB before their in-person Registry evaluation (with a waiting period of at least 2 weeks between evaluations), whereas the other two halves received the TCAB after they had become part of the Registry. The TCAB was administered to all participants by a single investigator. Two clinical evaluators, blinded to the Registry diagnosis of the subjects, independently classified the subjects as cognitively impaired, normal, or questionable on the basis of the results of the TCAB and a brief listing of medical illness and depressive symptoms. A final classification was achieved through consensus and subsequently compared with the Registry diagnosis, taken here to be the gold standard. RESULTS: Test scores of subjects assessed by TCAB before receiving the in-person assessment were compared with those of subjects receiving the in-person assessment first. There were no significant differences between mean scores of the two groups (those with TCAB first and those with TCAB last) for either cases or normal controls. High values of the kappa statistic were obtained for the two initial evaluators of the TCAB classification, demonstrating excellent interrater reliability. Regarding the reconciled TCAB classification, the ability of the TCAB to correctly classify subjects according to cognitive status, while controlling for potential confounders such as age and educational level, was assessed by means of discriminant analysis techniques. Knowledge of the TCAB classification and age allowed the correct classification of 95% of the participants; this was not significantly improved by knowledge of other potential determinants. Sensitivity and specificity were calculated under two schema for classifying those subjects in the "questionable" category. Positive and negative predictive values of the TCAB were computed assuming a prevalence of cognitive impairment of 10% in the older population. High negative predictive values (over 99%) were obtained under both schema, whereas the positive predictive values were seen to be more dependent on the classification of questionables. CONCLUSION: Research studies involving ascertainment of cognitive status of older people, particularly those that require periodic follow-up, such as those focusing on healthy aging, commonly suffer from lack of representativeness of subjects, often brought about by problems related to mobility of potential participants. It is also crucial that normal individuals who are recruited initially to serve as controls in epidemiologic studies of dementing illnesses be reevaluated periodically, and this may be hindered by the same obstacles. (ABSTRACT TRUNCATED)


Asunto(s)
Trastornos del Conocimiento/diagnóstico , Tamizaje Masivo/métodos , Vigilancia de la Población/métodos , Anciano , Estudios de Casos y Controles , Trastornos del Conocimiento/epidemiología , Intervalos de Confianza , Estudios Transversales , Humanos , Pruebas Neuropsicológicas , Valor Predictivo de las Pruebas , Estudios Prospectivos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Teléfono
15.
J Am Geriatr Soc ; 48(7): 800-6, 2000 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10894320

RESUMEN

OBJECTIVES: To study the association between cigarette smoking and Alzheimer's Disease (AD). DESIGN: Intrafamily case-control, with sibling controls and a variable number of controls per case. SETTING: AD cases were identified through the Research Registry of the University Hospitals of the Cleveland/Case Western Reserve University Alzheimer Center. PARTICIPANTS: Study subjects were 86 probable AD cases (index cases) and all of their full siblings, alive or dead, aged > or = 50 years, a total of 238 subjects. MEASUREMENTS: Exposure for each individual was ascertained with a questionnaire answered by several informants. Cognitive status of siblings of the AD cases (impaired or intact) was ascertained by telephone using validated instruments. Diagnosis of dementia in cognitively impaired siblings of index cases was not attempted. RESULTS: Chi-square analysis tested for departure from a random distribution of disease across smokers and nonsmokers within families. No significant departure was found utilizing all families (P > .40) nor utilizing those families where only the index case was affected (P > .90). Conditional logistic regression evaluated the association within families, controlling for age, sex, and education. Analyses both included and excluded secondary cases of cognitive impairment. No association was found between smoking and disease (OR = 1.26; 95% confidence interval, 0.66-2.42, and OR = 1.42; 95% confidence interval, 0.69-2.89, respectively). CONCLUSIONS: No significant association was found between smoking and cognitive status. Further, analyses based on the comparison of persons with AD with their unaffected siblings also suggest that smoking does not decrease the risk of AD.


Asunto(s)
Enfermedad de Alzheimer/etiología , Fumar/efectos adversos , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/epidemiología , Estudios de Casos y Controles , Intervalos de Confianza , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas , Núcleo Familiar , Ohio
16.
J Am Geriatr Soc ; 49(7): 980-4, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11527491

RESUMEN

OBJECTIVE: To examine the presence and extent of bias introduced by using surrogate respondents for healthy controls in a case-control study of Alzheimer's disease (AD). DESIGN: Comparative study of matched responses to questionnaire ascertaining lifestyle issues. SETTING: University Hospitals/Case Western Reserve University Alzheimer Center. PARTICIPANTS: Controls (n = 50) were identified through the Research Registry. Surrogates (n = 50) were their healthy relatives or friends. MEASUREMENTS: Answers in the areas of demographic and occupational history, smoking habits, medical history, dietary intake, and leisure and work activities were recorded. The analysis was based on methods for paired data. Continuous variables were analyzed, focusing on paired differences between self and surrogate responses. RESULTS: For occupations and exposures, over 80% of the surrogates agreed with the subjects on over 80% of the questions. On smoking history, over 90% of the surrogates agreed with the subjects on over 70% of the questions. On leisure and work activities, over 70% of the surrogates agreed with the subjects on over 50% of the questions. There was less agreement regarding medical history. For continuous variables, most paired t-tests of zero mean difference between self and surrogate responses resulted in nonrejection of this hypothesis. Computed mean differences were not always positive or always negative. CONCLUSION: We did not find systematic under- or overreporting by the surrogates of the controls. Therefore, if there are biases in the responses of surrogates of the AD cases in our case-control study, they would not be canceled out by using surrogates for the controls.


Asunto(s)
Enfermedad de Alzheimer/etiología , Sesgo , Estudios de Casos y Controles , Estilo de Vida , Anamnesis/normas , Proyectos de Investigación/normas , Encuestas y Cuestionarios/normas , Anciano , Enfermedad de Alzheimer/epidemiología , Interpretación Estadística de Datos , Escolaridad , Exposición a Riesgos Ambientales/estadística & datos numéricos , Ejercicio Físico , Femenino , Humanos , Actividades Recreativas , Masculino , Anamnesis/métodos , Ocupaciones/estadística & datos numéricos , Características de la Residencia/estadística & datos numéricos , Factores de Riesgo , Fumar/efectos adversos
17.
Diagn Microbiol Infect Dis ; 40(1-2): 21-5, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11448559

RESUMEN

Acute phase serum samples from 23 patients with Mycoplasma pneumoniae pneumonia were examined for specific antibodies with microparticle agglutination (MAG)-assay, complement fixation (CF)-test, IgM-specific ELISA, and Immunocard-based IgM-EIA. A novel 3-h IgA-ELISA (SeroMP-IgA) was tested to assess its diagnostic value. For MAG, CF, IgM-ELISA, card-based IgM-EIA, and IgA-ELISA positive results were obtained in 87%, 87%, 91%, 87%, and 100%, respectively. Overall concordance was 78%. Specificity testing of 46 healthy blood donors revealed an optimal diagnostic cut-off range of 22-30 IgA-ELISA binding units (BU)/mL resulting in 91%-100% specificity and 100%-96% sensitivity for serologic diagnosis of acute M. pneumoniae infection.


Asunto(s)
Anticuerpos Antibacterianos/sangre , Ensayo de Inmunoadsorción Enzimática/métodos , Inmunoglobulina A/sangre , Mycoplasma pneumoniae/inmunología , Neumonía por Mycoplasma/diagnóstico , Adolescente , Adulto , Niño , Humanos , Persona de Mediana Edad , Juego de Reactivos para Diagnóstico , Sensibilidad y Especificidad , Pruebas Serológicas/métodos , Especificidad de la Especie
18.
Eur J Pharmacol ; 269(2): 183-91, 1994 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-7851494

RESUMEN

Exendin-4 is a novel peptide from Heloderma suspectum venom which is 53% homologous with glucagon-like peptide-1 GLP-1-(7-36)NH2, a stimulant of cAMP-dependent H+ production in rat parietal cells. It was the aim of the present study to determine whether this effect of GLP-1-(7-36)NH2 is shared by exendin-4, and whether the responses to either peptide are blocked by exendin-(9-39)NH2, a competitive specific exendin receptor antagonist. In enriched rat parietal cells H+ production was measured indirectly by [14C]aminopyrine accumulation. cAMP production was determined by radioimmunoassay. [125I]GLP-1-(7-36)NH2 was prepared using chloramine T followed by high pressure liquid chromatography (HPLC) purification. Exendin-4 (10(-12) - 10(-8) M) stimulated [14C]aminopyrine accumulation in a concentration-dependent manner (EC50 = 7.6 x 10(-11) M). At the maximally effective concentration (10(-9) M) exendin-4 was as effective as GLP-1-(7-36)NH2 reaching 70-80% of the response to 10(-4) M histamine. Likewise, exendin-4 (10(-11) - 10(-7) M) stimulated parietal cell cAMP production up to 2.8-fold. Maximal stimulation by exendin-4 of [14C]aminopyrine accumulation was not affected by ranitidine (10(-4) M), but was concentration-dependently reduced by exendin-(9-39)NH2 (10(-11) - 10(-7) M). At the maximal concentration, exendin-(9-39)NH2 completely abolished the responses to 10(-9) M exendin-4 and to 10(-9) M GLP-1-(7-36)NH2 while not altering stimulation by 10(-4) M histamine. Binding of [125I]GLP-1-(7-36)NH2 to enriched parietal cells was displaced by exendin-4 (Ki = 4.6 x 10(-10) M) as well as by exendin-(9-39)NH2 (Ki = 4.0 x 10(-9) M).(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Glucagón/metabolismo , Lagartos/fisiología , Células Parietales Gástricas/metabolismo , Fragmentos de Péptidos/farmacología , Péptidos/farmacología , Receptores de Glucagón/agonistas , Receptores de Glucagón/antagonistas & inhibidores , Ponzoñas/farmacología , Aminopirina/metabolismo , Animales , Unión Competitiva/efectos de los fármacos , Membrana Celular/efectos de los fármacos , Membrana Celular/metabolismo , Reactivos de Enlaces Cruzados/farmacología , AMP Cíclico/biosíntesis , Exenatida , Femenino , Ácido Gástrico/metabolismo , Péptido 1 Similar al Glucagón , Péptidos Similares al Glucagón , Histamina/farmacología , Técnicas In Vitro , Células Parietales Gástricas/citología , Células Parietales Gástricas/efectos de los fármacos , Ratas , Ratas Wistar
19.
Eur J Gastroenterol Hepatol ; 13(6): 699-705, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11434597

RESUMEN

OBJECTIVE: To investigate the efficacy of high-dose interferon alpha (IFN-alpha) with or without ribavirin in interferon (IFN) non-responders. STUDY DESIGN: 304 chronic hepatitis C patients received 5 MU IFN-alpha2b (IntronA, Schering-Plough, Kenilworth, NJ, USA) three times a week for 3 months. Non-responders were randomized either to continue with IFN (IFN 5 MU/TIW followed by 10 MU/TIW, each for 3 months) alone (group A: n = 76, m: f = 54: 22, age 45.7 +/- 12 years, 16% cirrhosis, alanine aminotransferase [ALT] 66 +/- 35 U/l) or in combination with ribavirin (approximately 14 mg/kg/day) (group B: n = 81, m: f = 57: 24, age 48.2 +/- 12 years, 17% cirrhosis, ALT 71 +/- 40 U/l). At the end of treatment, patients were followed for 6 months. MAIN OUTCOME MEASURES: Virological response at end of treatment and 6 months thereafter. SETTING: University hospitals and tertiary referral centres. RESULTS: At the end of treatment, eight (10.8%) and 25 (31.3%, P= 0.0066) patients were HCV-RNA negative, and 51 and 39 were HCV-RNA positive, in groups A and B, respectively. There were 17 drop-outs in each group. Six months after treatment, only one patient in group A (1.3%) and seven patients (8.6%, P= 0.06) in group B had normal ALT and undetectable serum HCV-RNA. CONCLUSIONS: A combination of high-dose IFN with ribavirin induces a short-lasting complete response in about one-third of IFN-non-responders.


Asunto(s)
Antivirales/administración & dosificación , Hepatitis C Crónica/tratamiento farmacológico , Interferón-alfa/administración & dosificación , ARN Viral/análisis , Ribavirina/administración & dosificación , Adulto , Anciano , Secuencia de Bases , Relación Dosis-Respuesta a Droga , Quimioterapia Combinada , Femenino , Estudios de Seguimiento , Hepatitis C Crónica/diagnóstico , Humanos , Interferones/administración & dosificación , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Organización y Administración , Reacción en Cadena de la Polimerasa , Probabilidad , Estudios Prospectivos , Valores de Referencia , Insuficiencia del Tratamiento , Resultado del Tratamiento
20.
Rofo ; 175(11): 1572-6, 2003 Nov.
Artículo en Alemán | MEDLINE | ID: mdl-14610712

RESUMEN

PURPOSE: To evaluate the potential of raw data-based multidimensional adaptive filtering (MAF) by determining its effects on image noise and image quality in multi-slice spiral CT (MSCT) of the pelvis. MATERIALS AND METHODS: Fifty patients with rectal and bladder cancer were examined with MSCT using a high-resolution protocol. Reconstructions were performed with dedicated reconstruction software and a standard algorithm, both without and with MAF, with four different modification fractions selected from 5 % to 20 %. The noise was measured at six anatomic sites of the pelvis. Image quality and image noise were rated on a 5-point-scale. RESULTS: Modification fractions of 15 % (15 % MAF) and 20 % (20 % MAF) significantly reduced the noise level at all measurement points in comparison with lower modification fractions (p < 0.05). Overall quality of the reconstructed images was rated better with 15 % MAF and 20 % MAF than with other modification fractions (p < 0.05). No further improvement of the image quality was observed by changing from 15 % MAF to 20 % MAF (p > 0.05). 15 % MAF achieved a mean noise reduction of 33 %. All examinations showed an improved visualization of the rectal wall and perirectal lymph nodes. CONCLUSIONS: MAF improves the image quality by reducing the noise level and by removing noise structures. This technique offers new perspectives to radiation dose reduction in CT.


Asunto(s)
Pelvis/diagnóstico por imagen , Tomografía Computarizada Espiral/métodos , Humanos , Procesamiento de Imagen Asistido por Computador , Análisis de Regresión , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Tomografía Computarizada Espiral/normas
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