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1.
Ultrasound Obstet Gynecol ; 64(2): 155-163, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38452144

RESUMEN

OBJECTIVE: To assess the diagnostic performance of transvaginal sonography (TVS) for the preoperative evaluation of lymph-node metastasis in gynecological cancer. METHODS: This was a systematic review and meta-analysis of studies published between January 1990 and May 2023 evaluating the role of ultrasound in detecting pelvic lymph-node metastasis (index test) in gynecological cancer, using histopathological analysis as the reference standard. The quality of included studies was assessed using the Quality Assessment of Diagnostic Accuracy Studies-2 tool. Pooled sensitivity, specificity and diagnostic odds ratio were estimated. RESULTS: The literature search identified 2638 citations. Eight studies reporting on a total of 967 women were included. The mean prevalence of pelvic lymph-node metastasis was 24.2% (range, 14.0-65.6%). The risk of bias was low for most domains assessed. Pooled sensitivity, specificity and diagnostic odds ratio of TVS were 41% (95% CI, 26-58%), 98% (95% CI, 93-99%) and 32 (95% CI, 14-72), respectively. High heterogeneity was found between studies for both sensitivity and specificity. CONCLUSION: TVS showed a high pooled specificity for the detection of pelvic lymph-node metastasis in gynecological cancer, but pooled sensitivity was low. © 2024 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.


Asunto(s)
Neoplasias de los Genitales Femeninos , Ganglios Linfáticos , Metástasis Linfática , Sensibilidad y Especificidad , Ultrasonografía , Humanos , Femenino , Metástasis Linfática/diagnóstico por imagen , Ultrasonografía/métodos , Ganglios Linfáticos/diagnóstico por imagen , Ganglios Linfáticos/patología , Neoplasias de los Genitales Femeninos/diagnóstico por imagen , Neoplasias de los Genitales Femeninos/patología , Pelvis/diagnóstico por imagen
2.
Anim Genet ; 48(3): 315-329, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28094449

RESUMEN

Biodiversity studies are more efficient when large numbers of breeds belonging to several countries are involved, as they allow for an in-depth analysis of the within- and between-breed components of genetic diversity. A set of 21 microsatellites was used to investigate the genetic composition of 24 Creole goat breeds (910 animals) from 10 countries to estimate levels of genetic variability, infer population structure and understand genetic relationships among populations across the American continent. Three commercial transboundary breeds were included in the analyses to investigate admixture with Creole goats. Overall, the genetic diversity of Creole populations (mean number of alleles = 5.82 ± 1.14, observed heterozygosity = 0.585 ± 0.074) was moderate and slightly lower than what was detected in other studies with breeds from other regions. The Bayesian clustering analysis without prior information on source populations identified 22 breed clusters. Three groups comprised more than one population, namely from Brazil (Azul and Graúna; Moxotó and Repartida) and Argentina (Long and shorthair Chilluda, Pampeana Colorada and Angora-type goat). Substructure was found in Criolla Paraguaya. When prior information on sample origin was considered, 92% of the individuals were assigned to the source population (threshold q ≥ 0.700). Creole breeds are well-differentiated entities (mean coefficient of genetic differentiation = 0.111 ± 0.048, with the exception of isolated island populations). Dilution from admixture with commercial transboundary breeds appears to be negligible. Significant levels of inbreeding were detected (inbreeding coefficient > 0 in most Creole goat populations, P < 0.05). Our results provide a broad perspective on the extant genetic diversity of Creole goats, however further studies are needed to understand whether the observed geographical patterns of population structure may reflect the mode of goat colonization in the Americas.


Asunto(s)
Variación Genética , Genética de Población , Cabras/genética , Alelos , Américas , Animales , Teorema de Bayes , Cruzamiento , Frecuencia de los Genes , Marcadores Genéticos , Genotipo , Geografía , Heterocigoto , Repeticiones de Microsatélite , Análisis de Secuencia de ADN
3.
Gynecol Obstet Invest ; 78(2): 130-5, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24903217

RESUMEN

OBJECTIVE: To determine whether oral glucose tolerance tests (OGTT) play a role as predictors of preeclampsia (PET) in pregnant women. METHODS: A retrospective case-control study was conducted in 2,002 singleton pregnancies that had a uterine artery (UtA) Doppler at 22-25 weeks and an OGTT. The UtA Doppler and OGTT were adjusted based on maternal characteristics, and the results were expressed as multiples of the expected normal median and compared between groups. Logistic regression analysis was used to determine whether maternal characteristics, OGTT, and UtA Doppler significantly contribute to the prediction of early- (<34 weeks), intermediate- (34-37 weeks), or late-onset (>37 weeks) PET. The performance of the screening was determined by ROC curves. RESULTS: Women who developed PET were characterized by an older maternal age, an increased body mass index, and an altered UtA Doppler. The group with intermediate-onset PET was the only one associated with higher 2-hour OGTT levels compared to controls. Combined models were developed via logistic regression analysis using maternal characteristics, UtA Doppler, and OGTT to predict PET. These combined models were able to detect around 74, 42, and 21% of women who later developed early-, intermediate-, or late-onset PET, respectively, with only a 5% false-positive rate. CONCLUSIONS: This study shows that the combination of maternal characteristics, second-trimester UtA Doppler, and OGTT is a predictor of the development of PET in healthy pregnant women.


Asunto(s)
Prueba de Tolerancia a la Glucosa , Preeclampsia/diagnóstico , Adulto , Índice de Masa Corporal , Estudios de Casos y Controles , Cesárea/estadística & datos numéricos , Diabetes Gestacional/epidemiología , Femenino , Edad Gestacional , Humanos , Modelos Logísticos , Edad Materna , Preeclampsia/epidemiología , Embarazo , Nacimiento Prematuro/epidemiología , Curva ROC , Estudios Retrospectivos , Ultrasonografía , Arteria Uterina/diagnóstico por imagen
4.
Med Intensiva ; 36(4): 294-306, 2012 May.
Artículo en Español | MEDLINE | ID: mdl-22014424

RESUMEN

Mechanical ventilation is a therapeutic intervention involving the temporary replacement of ventilatory function with the purpose of improving symptoms in patients with acute respiratory failure. Technological advances have facilitated the development of sophisticated ventilators for viewing and recording the respiratory waveforms, which are a valuable source of information for the clinician. The correct interpretation of these curves is crucial for the correct diagnosis and early detection of anomalies, and for understanding physiological aspects related to mechanical ventilation and patient-ventilator interaction. The present study offers a guide for the interpretation of the airway pressure and flow and volume curves of the ventilator, through the analysis of different clinical scenarios.


Asunto(s)
Respiración Artificial , Insuficiencia Respiratoria/fisiopatología , Insuficiencia Respiratoria/terapia , Enfermedad Aguda , Humanos , Respiración
5.
J Hosp Infect ; 105(4): 670-677, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32330557

RESUMEN

BACKGROUND: Clostridioides difficile is transmitted through endospores. Most disinfection procedures for these structures deploy high concentrations of chlorine-derived compounds such as sodium hypochlorite (NaOCl) and sodium dichloroisocyanurate (NaDCC). However, these substances are linked to undesirable public health and environmental issues. AIM: To compare the efficacy of NaCl-derived electrochemically activated solution (ECAS, 0.18% w/v NaOCl, pH=9.6-10.3), commercial bleach (5000 ppm, 2.83% w/v NaOCl, pH=5.6) and NaDCC (1000 ppm, pH=6.8) to inactivate C. difficile endospores on surfaces using a standard quantitative test (EPA MO-21-03). FINDINGS: Ten representative reference and field strains from multi-locus sequence typing Clades 1-5 were assayed (N=10). Irrespective of the phylogenetic background of the strains, ECAS showed comparable or better log reduction values [mean=3.22, 95% confidence interval (CI) 0.40-5.56] than bleach (mean=2.74, 95% CI 0.12-5.50) and NaDCC (mean=2.02, 95% CI 0.10-5.12). Cyclic voltammetry measurements revealed similar electrochemical behaviours and open-circuit potentials for ECAS and NaOCl. Congruently, similar morphologies for spores treated with these two compounds were observed by transmission electron microscopy. A factorial design demonstrated that exposure time, but not activation time, influenced the efficacy of ECAS. CONCLUSIONS: ECAS and NaOC were found to have functional equivalence and may have a common mechanism of action.


Asunto(s)
Antiinfecciosos/farmacología , Clostridioides difficile/efectos de los fármacos , Desinfección/métodos , Cloruro de Sodio/química , Esporas Bacterianas/efectos de los fármacos , Antiinfecciosos/química , Clostridioides difficile/clasificación , Clostridioides difficile/genética , Técnicas Electroquímicas , Humanos , Tipificación de Secuencias Multilocus
6.
Arch Environ Contam Toxicol ; 56(1): 165-72, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18427709

RESUMEN

A Bayesian risk assessment of the exposure of children up to 6 years of age to trace elements in the sandy substrate of municipal playgrounds in Madrid, Spain was carried out. As a first step, exposure variables and parameters were borrowed from US Environmental Protection Agency (EPA) databases. However, the use of these non-site-specific exposure data introduced a high arbitrariness in the assumed distributions, which, in the Bayes approach, translates into a high uncertainty for those distributions that is also reflected in the risk outcome. In order to reduce this uncertainty, site-specific values for children's body weight and exposure frequency were determined from three surveys of 75, 56, and 34 individuals, respectively, carried out in randomly selected playgrounds in Madrid. This information was used in a Bayesian approach to modify the prior distributions of exposure frequency and body weight adapted from the literature. As a result, the predictive distributions of risk values for arsenic and mercury presented a reduced arbitrariness and a significantly lower uncertainty than those obtained either from the prior distributions borrowed from the US EPA or from the limited data gathered in Madrid separately.


Asunto(s)
Teorema de Bayes , Exposición a Riesgos Ambientales/efectos adversos , Monitoreo del Ambiente/métodos , Contaminantes Ambientales/efectos adversos , Medición de Riesgo/métodos , Arsenicales/efectos adversos , Niño , Preescolar , Exposición a Riesgos Ambientales/estadística & datos numéricos , Monitoreo del Ambiente/estadística & datos numéricos , Humanos , Compuestos de Mercurio/efectos adversos , Juego e Implementos de Juego , Recreación , Medición de Riesgo/estadística & datos numéricos , España
7.
BJOG ; 114(6): 763-6, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17516970

RESUMEN

After 857 women with Essure system inserted for tubal obstruction as a method of sterilization in an outpatient setting, insertion is achieved in close to 99% of the women. Physician described the procedure as very difficult in 15% of the cases, mainly due to anatomical tubal anomalis or tubal spasm, and women felt highly satisfied in all cases.


Asunto(s)
Procedimientos Quirúrgicos Ambulatorios/normas , Satisfacción del Paciente , Esterilización Tubaria/normas , Adulto , Procedimientos Quirúrgicos Ambulatorios/métodos , Procedimientos Quirúrgicos Ambulatorios/psicología , Estudios de Cohortes , Falla de Equipo , Femenino , Humanos , Histeroscopía/métodos , Histeroscopía/psicología , Histeroscopía/normas , Persona de Mediana Edad , Estudios Prospectivos , Esterilización Tubaria/métodos , Esterilización Tubaria/psicología , Resultado del Tratamiento
8.
J Phys Condens Matter ; 19(26): 266008, 2007 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-21694077

RESUMEN

It is well known that the exchange-correlation (XC) potential at a metal surface has an image-like asymptotic behaviour given by -1/4(z-z(0)), where z is the coordinate perpendicular to the surface. Using a suitable fully non-local functional prescription, we evaluate self-consistently the XC potential with the correct image behaviour for simple jellium surfaces in the range of metallic densities. This allows a proper comparison between the corresponding image-plane position, z(0), and other related quantities such as the centroid of an induced charge by an external perturbation. As a by-product, we assess the routinely used local density approximation when evaluating electron density profiles, work functions, and surface energies by focusing on the XC effects included in the fully non-local description.

9.
Vet Parasitol ; 146(1-2): 9-16, 2007 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-17374452

RESUMEN

Trypanosomosis caused by Trypanosoma vivax has been a constraint for cattle production in the Bolivian lowlands, since it was introduced in 1996. Flooded areas like the Bolivian Pantanal have a suitable environment for the presence and transmission of Salivarian trypanosomes and farmers from that region often report trypanosomosis-like problems on their farms. The objective of the present study, therefore, was to characterize the epidemiology of bovine trypanosomosis in the Bolivian Pantanal. In order to achieve this objective, 202 cattle from the province of Angel Sandoval and 209 cattle from the province of German Busch were randomly sampled (the Pantanal is located in both provinces). Twenty-nine farms in both provinces were visited, the farmers interviewed, and biologic samples collected from their cattle. Samples were submitted for parasitological and PCR evaluation and the prevalence of bovine trypanosomosis was estimated for each province. Laboratory results were correlated with the sampled animals packed cell volume (PCV) and body condition (BC) scores and the observed T. vivax parasites measured for morphometry analysis. Results from this study show differences in morphometric measures between T. vivax parasites from each province. Differences between provinces were also observed in the T. vivax-related disease situation. While in Angel Sandoval the PCV and BC of T. vivax-affected animals were significantly lower than those of the T. vivax-negative animals, in German Busch no differences were observed in the PCV and BC of T. vivax-positive or negative animals. Animal prevalence of T. vivax in Angel Sandoval was 27.79% (95% CI: 14.52-44.28) and in German Busch was 19.03% (95% CI: 9.19-30.75). The T. evansi animal prevalence in each province was 0.99% (95% CI: 0.27-2.99) and 5.71% (95% CI: 2.43-12.19), respectively. Based on questionnaire and laboratory results, it was concluded that trypanosomosis is a primary constraint for cattle production in the Bolivian Pantanal.


Asunto(s)
Tripanosomiasis Bovina/epidemiología , Animales , Bolivia/epidemiología , Bovinos , Ecosistema , Masculino , Prevalencia , Trypanosoma/clasificación , Trypanosoma/aislamiento & purificación
10.
Chemosphere ; 66(3): 505-13, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16844191

RESUMEN

Eighty samples of sandy substrate were collected in November 2002 and 2003, from 20 municipal playgrounds in Madrid (Spain) to assess the potential adverse health effects of the exposure of children to trace elements in this material during their games. In each playground, two 500 g samples were collected, dried at 45 degrees C for 48 h, sieved below 100 microm, acid digested and analyzed by ICP-MS. Doses contacted through ingestion and inhalation and the dose absorbed through the skin were calculated using USEPAs hourly exposure parameters for children and the results of an in situ survey. The toxicity values considered in this study were mostly taken from the US DoEs RAIS compilation. The results of the risk assessment indicate that the highest risk is associated with ingestion of soil particles and that the trace element of most concern is arsenic, the exposure to which results in a cancer risk value of 4.19 x 10(-6), close to the 1 x 10(-5) probability level deemed unacceptable by most regulatory agencies. Regarding non-cancer effects, exposure to playground substrate yields an aggregate Hazard Index of 0.28, below the threshold value of 1 (with As, again, as the largest single contributor, followed by Pb, Cr, Al and Mn). Although the uncertainties associated with the estimates of toxicity values and exposure factors should be reduced before any definite conclusions regarding potential health effects are drawn, risk assessment has proven to be a very useful tool to identify the contaminants and exposure pathways of most concern in urban environments.


Asunto(s)
Exposición a Riesgos Ambientales/análisis , Medición de Riesgo/métodos , Oligoelementos/análisis , Exposición a Riesgos Ambientales/efectos adversos , Monitoreo del Ambiente/métodos , Geografía , Humanos , Juego e Implementos de Juego , Recreación , España
11.
Clin Microbiol Infect ; 23(11): 845-853, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28389276

RESUMEN

OBJECTIVES: Shigella sonnei is a globally important diarrhoeal pathogen tracked through the surveillance network PulseNet Latin America and Caribbean (PNLA&C), which participates in PulseNet International. PNLA&C laboratories use common molecular techniques to track pathogens causing foodborne illness. We aimed to demonstrate the possibility and advantages of transitioning to whole genome sequencing (WGS) for surveillance within existing networks across a continent where S. sonnei is endemic. METHODS: We applied WGS to representative archive isolates of S. sonnei (n = 323) from laboratories in nine PNLA&C countries to generate a regional phylogenomic reference for S. sonnei and put this in the global context. We used this reference to contextualise 16 S. sonnei from three Argentinian outbreaks, using locally generated sequence data. Assembled genome sequences were used to predict antimicrobial resistance (AMR) phenotypes and identify AMR determinants. RESULTS: S. sonnei isolates clustered in five Latin American sublineages in the global phylogeny, with many (46%, 149 of 323) belonging to previously undescribed sublineages. Predicted multidrug resistance was common (77%, 249 of 323), and clinically relevant differences in AMR were found among sublineages. The regional overview showed that Argentinian outbreak isolates belonged to distinct sublineages and had different epidemiologic origins. CONCLUSIONS: Latin America contains novel genetic diversity of S. sonnei that is relevant on a global scale and commonly exhibits multidrug resistance. Retrospective passive surveillance with WGS has utility for informing treatment, identifying regionally epidemic sublineages and providing a framework for interpretation of prospective, locally sequenced outbreaks.


Asunto(s)
Disentería Bacilar , Enfermedades Transmitidas por los Alimentos , Shigella sonnei/genética , Región del Caribe/epidemiología , ADN Bacteriano/análisis , ADN Bacteriano/genética , Brotes de Enfermedades/prevención & control , Brotes de Enfermedades/estadística & datos numéricos , Farmacorresistencia Bacteriana , Disentería Bacilar/epidemiología , Disentería Bacilar/microbiología , Enfermedades Transmitidas por los Alimentos/epidemiología , Enfermedades Transmitidas por los Alimentos/microbiología , Humanos , América Latina/epidemiología , Vigilancia en Salud Pública , Estudios Retrospectivos , Shigella sonnei/efectos de los fármacos , Secuenciación Completa del Genoma
12.
Vet Parasitol ; 136(2): 119-26, 2006 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-16359805

RESUMEN

There are several T. vivax specific primers developed for PCR diagnosis. Most of these primers were validated under different DNA extraction methods and study designs leading to heterogeneity of results. The objective of the present study was to validate PCR as a diagnostic test for T. vivax trypanosomosis by means of determining the test sensitivity of different published specific primers with different sample preparations. Four different DNA extraction methods were used to test the sensitivity of PCR with four different primer sets. DNA was extracted directly from whole blood samples, blood dried on filter papers or blood dried on FTA cards. The results showed that the sensitivity of PCR with each primer set was highly dependant of the sample preparation and DNA extraction method. The highest sensitivities for all the primers tested were determined using DNA extracted from whole blood samples, while the lowest sensitivities were obtained when DNA was extracted from filter paper preparations. To conclude, the obtained results are discussed and a protocol for diagnosis and surveillance for T. vivax trypanosomosis is recommended.


Asunto(s)
ADN Protozoario/aislamiento & purificación , Reacción en Cadena de la Polimerasa/veterinaria , Enfermedades de las Ovejas/diagnóstico , Trypanosoma vivax/aislamiento & purificación , Tripanosomiasis/veterinaria , Animales , Bolivia , Bovinos , Cartilla de ADN/química , Cartilla de ADN/normas , ADN Protozoario/sangre , Masculino , Parasitemia/parasitología , Parasitemia/veterinaria , Reacción en Cadena de la Polimerasa/métodos , Reacción en Cadena de la Polimerasa/normas , Sensibilidad y Especificidad , Ovinos , Enfermedades de las Ovejas/sangre , Enfermedades de las Ovejas/parasitología , Trypanosoma vivax/genética , Tripanosomiasis/diagnóstico , Tripanosomiasis/parasitología , Tripanosomiasis Bovina/parasitología
13.
J Immunol Methods ; 427: 1-5, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26321053

RESUMEN

VP1, VP2 and VP3 molecules of hepatitis A virus are exposed capsid proteins that have shown to be antigenic and are used for diagnosis in recombinant-antigen commercial kits. In this study, we developed a sequence analysis in order to predict diagnostic peptide epitopes, followed by their spot synthesis on functionalized cellulose paper (Pepscan). This paper with synthetic peptides was tested against a sera pool of hepatitis A patients. Two peptide sequences, that have shown an antigenic recognition, were selected for greater scale synthesis on resin. A dimeric form of one of these peptides (IMT-1996), located in the C-Terminus region of protein VP1, was antigenic with a recognition frequency of 87-100% of anti-IgG antibodies and 100% of anti-IgM antibodies employing the immunological assays MABA and ELISA. We propose peptide IMT-1996, with less than twenty residues, as a cheaper alternative for prevalence studies and diagnosis of hepatitis A infection.


Asunto(s)
Proteínas de la Cápside/inmunología , Hepatitis A/diagnóstico , Proteínas Estructurales Virales/inmunología , Secuencia de Aminoácidos , Anticuerpos Antivirales , Antígenos Virales/inmunología , Biomarcadores/análisis , Ensayo de Inmunoadsorción Enzimática , Hepatitis A/inmunología , Humanos , Immunoblotting , Proteínas Recombinantes/síntesis química , Proteínas Recombinantes/inmunología , Sensibilidad y Especificidad
14.
FEBS Lett ; 382(1-2): 31-6, 1996 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-8612759

RESUMEN

Mitochondrial free Ca2+ may regulate mitochondrial ATP production during cardiac exercise. Here, using laser scanning confocal microscopy of adult rabbit cardiac myocytes co-loaded with Fluo-3 to measure free Ca2+ and tetramethylrhodamine methylester to identify mitochondria, we measured cytosolic and mitochondrial Ca2+ transients during the contractile cycle. In resting cells, cytosolic and mitochondrial Fluo-3 signals were similar. During electrical pacing, transients of Fluo-3 fluorescence occurred in both the cytosolic and mitochondrial compartments. Both the mitochondrial and the cytosolic transients were potentiated by isoproterenol. These experiments show directly that mitochondrial free Ca2+ rises and falls during excitation-contraction coupling in cardiac myocytes and that changes of mitochondrial Ca2+ are kinetically competent to regulate mitochondrial metabolism on a beat-to-beat basis.


Asunto(s)
Calcio/metabolismo , Mitocondrias Cardíacas/metabolismo , Contracción Miocárdica/fisiología , Miocardio/metabolismo , Compuestos de Anilina , Animales , Células Cultivadas , Citosol/metabolismo , Estimulación Eléctrica , Fluoresceínas , Colorantes Fluorescentes , Microscopía Confocal , Miocardio/química , Conejos , Rodaminas , Xantenos
15.
EXS ; 76: 99-114, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-8805791

RESUMEN

During myocardial ischemia, a large reduction of tissue pH develops, and tissue pH returns to normal after reperfusion. In recent studies, we evaluated the role of pH in ischemia/reperfusion injury to cultured cardiac myocytes and perfused papillary muscles. Acidosis (pH < or = 7.0) protected profoundly against cell death during ischemia. However, the return from acidotic to normal pH after reperfusion caused myocytes to lose viability. This worsening of injury is a 'pH paradox' and was mediated by changes of intracellular pH (pH(i)), since manipulations that caused pH(i), to increase more rapidly after reperfusion accelerated cell killing, whereas manipulations that delayed the increase of pH(i) prevented loss of myocyte viability. Specifically, inhibition of the Na+/H+ exchanger with dimethylamiloride or HOE694 delayed the return of physiologic pH(i) after reperfusion and prevented reperfusion-induced cell killing to both cultured myocytes and perfused papillary muscle. Dimethylamiloride and HOE694 did not reduce intracellular free Ca2+ during reperfusion. By contrast, reperfusion with dichlorobenzamil, an inhibitor of Na+/Ca2+ exchange, decreased free Ca2+ but did not reduce cell killing. Thus, the pH paradox is not Ca(2+)-dependent. Our working hypothesis is that ischemia activates hydrolytic enzymes, such as phospholipases and proteases, whose activity is inhibited at acidotic pH. Upon reperfusion, the return to normal pH releases this inhibition and hydrolytic injury ensues. Increasing pH(i) may also induce a pH-dependent mitochondrial permeability transition and activate the myofibrillar ATPase, effects that increase ATP demand and compromise ATP supply. In conclusion, acidotic pH is generally protective in ischemia, whereas a return to physiologic pH precipitates lethal reperfusion injury to myocytes.


Asunto(s)
Daño por Reperfusión Miocárdica/metabolismo , Miocardio/metabolismo , Animales , Calcio/metabolismo , Muerte Celular , Hipoxia de la Célula , Humanos , Concentración de Iones de Hidrógeno , Líquido Intracelular/metabolismo , Modelos Cardiovasculares , Isquemia Miocárdica/terapia , Daño por Reperfusión Miocárdica/etiología , Daño por Reperfusión Miocárdica/patología , Miocardio/patología , Músculos Papilares/metabolismo , Conejos , Ratas
16.
Comb Chem High Throughput Screen ; 2(1): 39-51, 1999 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10420975

RESUMEN

We have assessed the metabolic activity of freshly isolated and commercially preserved rat, monkey, and human primary hepatocytes in a 96 well plate format utilizing eight beta-adrenolytic drugs as model compounds. Sample introduction from 96 well plates, HPLC solvent delivery, mass spectrometric (MS) detection, and/or UV detection were fully integrated and operated unattended. After drugs were incubated with hepatocytes for three or six hr, LC-MS analyses were carried out to determine the amount of drug which was not metabolized. Two LC-MS methods were used which had a sample throughput of 4 samples/hr and 12 samples/hr. Under optimal conditions, this hepatic assay could screen 300 samples/week or 1200 samples/month. Although freshly isolated hepatocytes were more active, commercially available rat, monkey, and human primary isolated hepatocytes metabolized drug substrates in similar relative rank orders. This drug-hepatocyte assay provides useful information for prioritizing pharmaceutical leads in relative rank orders or in a high/low manner according to their resistance toward liver metabolism.


Asunto(s)
Cromatografía Liquida/métodos , Hígado/metabolismo , Espectrometría de Masas/métodos , Animales , Células Cultivadas , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Haplorrinos , Humanos , Hígado/citología , Hígado/efectos de los fármacos , Ratas , Espectrofotometría Ultravioleta
17.
Phys Rev E Stat Nonlin Soft Matter Phys ; 70(6 Pt 1): 061601, 2004 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-15697375

RESUMEN

We analyze the density profiles for liquid-vapor interfaces within two density functional (DF) approximations, applied to simple fluid models which have low ratios between their triple and critical temperatures. The observation of layering structures at low T is discussed in relation with the Fisher-Widom line for each model. Although we find no apparent correlation between the amplitude of the oscillatory density decay mode and the approach to T(FW) , that temperature sets a threshold for the generation of nonmonotonic structures within a fixed distance of the interface. The rapid decay of the oscillatory mode amplitude with T may be interpreted as a result of the capillary wave (CW) damping of strongly structured intrinsic density profiles. The layering in the presence of gravitylike external fields indicate that the effective transverse size which might be built in the DF approximations is around 10+/-2 molecular diameters; however, that interpretation has to allow for an effectively reduced damping exponent, i.e., an effective surface tension for the CW Hamiltonian which is larger than the value obtained directly from the DF grand-potential minimization.

18.
Plast Reconstr Surg ; 104(4): 905-10, 1999 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10654726

RESUMEN

Sphincter pharyngoplasty is a surgical procedure for managing velopharyngeal insufficiency after palatal closure. This procedure is intended to create an active diaphragm for velopharyngeal closure. The purpose of this study was to evaluate velopharyngeal motion after sphincter pharyngoplasty, by using selective electromyography and simultaneous videonasopharyngoscopy. Twenty-five patients who were subjected to sphincter pharyngoplasty from 1985 to 1996 were reviewed. All conditions were evaluated by using electromyography with simultaneous videonasopharyngoscopy. The following velopharyngeal muscles were examined: superior constrictor pharyngeus, palatopharyngeus, and levator veli palatini. The palatopharyngeus was included in the superiorly based surgical flaps inserted at the posterior pharyngeal wall. Twenty-three patients (92 percent) showed complete velopharyngeal closure. The two patients with residual velopharyngeal insufficiency showed a defect size of 20 and 25 percent. None of the patients showed electromyographic activity at the superiorly based flaps, indicating absence of activity of the palatopharyngeus muscles. However, all patients showed normal electromyographic activity at the superior constrictor pharyngeus and the levator veli palatini. Videonasopharyngoscopy demonstrated that lateral pharyngeal wall movements, which ranged from 25 to 40 percent, were related to strong electromyographic activity at the superior constrictor pharyngeus. It is concluded that the superiorly based pharyngeal flaps of the sphincter pharyngoplasty do not seem to create an active diaphragm for velopharyngeal closure. Moreover, the observed sphinctering seems to be passive, caused by the contraction of the superior constrictor pharyngeus.


Asunto(s)
Fisura del Paladar/cirugía , Electromiografía , Faringe/cirugía , Cirugía Asistida por Video , Adolescente , Adulto , Fisura del Paladar/patología , Fisura del Paladar/fisiopatología , Deglución , Electromiografía/métodos , Femenino , Humanos , Masculino , Faringe/patología , Faringe/fisiopatología , Estudios Retrospectivos , Habla , Resultado del Tratamiento , Cirugía Asistida por Video/métodos
19.
Adv Space Res ; 12(4): 63-6, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-11538157

RESUMEN

The behavior of an aqueous-dominant multicomponent cometary model is examined at high doses of ionizing radiation. The system is composed of a water mixture of HCN (0.2 mol dm-3), CH3CN (0.04 mol dm-3), C2H5CN (0.02 mol dm-3), CH3OH (0.12 mol dm-3) and HCO2H (0.01 mol dm-3. It was exposed to gamma rays at doses up to 18.5 MGy. The chemical kinetic database used in the computer treatment of experimental data consists of 79 reactions. A complex mixture of products has been synthesized: gases, amino acids, carboxylic acids and polymeric material. The results suggest that the pristine material in cometary nuclei may have been chemically altered by the action of cosmic rays and embedded radionuclides.


Asunto(s)
Aminoácidos/síntesis química , Ácidos Carboxílicos/síntesis química , Rayos gamma , Gases/síntesis química , Meteoroides , Polímeros/síntesis química , Bases de Datos Factuales , Formiatos/química , Formiatos/efectos de la radiación , Hidrocarburos/síntesis química , Cianuro de Hidrógeno/química , Cianuro de Hidrógeno/efectos de la radiación , Metanol/química , Metanol/efectos de la radiación , Modelos Químicos , Nitrilos/química , Nitrilos/efectos de la radiación , Radioquímica , Agua/química
20.
An Med Interna ; 15(10): 538-40, 1998 Oct.
Artículo en Español | MEDLINE | ID: mdl-9844230

RESUMEN

We describe two patients with diffuse alveolar hemorrhage and Wegener s Granulomatosis. In both cases, ANCA were demonstrated. We discuss the profit about ANCA s in the diagnosis and management the systemic vasculitis.


Asunto(s)
Anticuerpos Anticitoplasma de Neutrófilos/sangre , Granulomatosis con Poliangitis/inmunología , Resultado Fatal , Femenino , Hemoptisis/etiología , Hemoptisis/inmunología , Humanos , Enfermedades Pulmonares/etiología , Enfermedades Pulmonares/inmunología , Masculino , Persona de Mediana Edad
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