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1.
Conserv Biol ; : e14296, 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38770838

RESUMEN

Marine protected areas (MPAs) globally serve conservation and fisheries management goals, generating positive effects in some marine ecosystems. Surf zones and sandy beaches, critical ecotones bridging land and sea, play a pivotal role in the life cycles of numerous fish species and serve as prime areas for subsistence and recreational fishing. Despite their significance, these areas remain understudied when evaluating the effects of MPAs. We compared surf zone fish assemblages inside and outside MPAs across 3 bioregions in California (USA). Using seines and baited remote underwater videos (BRUVs), we found differences in surf zone fish inside and outside MPAs in one region. Inside south region MPAs, we observed higher abundance (Tukey's honest significant difference [HSD] = 0.83, p = 0.0001) and richness (HSD = 0.22, p = 0.0001) in BRUVs and greater biomass (HSD = 0.32, p = 0.0002) in seine surveys compared with reference sites. Selected live-bearing, fished taxa were positively affected by MPAs. Elasmobranchs displayed greater abundance in BRUV surveys and higher biomass in seine surveys inside south region MPAs (HSD = 0.35, p = 0.0003 and HSD = 0.23, p = 0.008, respectively). Although we observed no overall MPA signal for Embiotocidae, abundances of juvenile and large adult barred surfperch (Amphistichus argenteus), the most abundant fished species, were higher inside MPAs (K-S test D = 0.19, p < 0.0001). Influence of habitat characteristics on MPA performance indicated surf zone width was positively associated with fish abundance and biomass but negatively associated with richness. The south region had the largest positive effect size on all MPA performance metrics. Our findings underscored the variability in species richness and composition across regions and survey methods that significantly affected differences observed inside and outside MPAs. A comprehensive assessment of MPA performance should consider specific taxa, their distribution, and the effects of habitat factors and geography.


Evaluación de la influencia de las áreas marinas protegidas sobre los peces de la zona de rompientes Resumen Las áreas marinas protegidas (AMP) cumplen los objetivos de conservación y manejo de pesquerías a nivel mundial, lo que genera efectos positivos en algunos ecosistemas marinos. Las zonas de rompientes y las playas arenosas, ecotonos importantes que conectan la tierra con el mar, tienen un papel esencial en el ciclo de vida de varios peces y fungen como áreas óptimas para la pesca recreativa y de sustento. A pesar de su importancia, estas áreas están poco estudiadas con respecto a la evaluación del efecto de las AMP. Comparamos la composición de peces del área de rompientes dentro y fuera de las AMP de tres bioregiones de California, EUA. Usamos chinchorros y videos submarinos con carnada (BRUVs) y descubrimos diferencias en los peces de la zona de rompientes dentro y fuera de las AMP en una región. Dentro de las AMP de la región sur observamos una mayor abundancia (diferencia significativa honesta de Tukey [DSH]  =  0.83, p = 0.0001) y riqueza (DSH  =  0.22, p = 0.0001) en los BRUV y una mayor biomasa (DSH  =  0.32, p = 0.0002) en los censos con chinchorro en comparación con los sitios de referencia. Los taxones seleccionados de peces de sustento fueron afectados de manera positiva por las AMP. Los elasmobranquios mostraron una mayor abundancia en los BRUV y una mayor biomasa en los censos con chinchorro dentro de las AMP de la región sur (DSH  =  0.35, p = 0.0003 y DSH  =  0.23, p = 0.008, respectivamente). Aunque no observamos una señal generalizada de las AMP para la familia Embiotocidae, la abundancia de Amphistichus argenteus juveniles y adultos, la especie pescada más abundante, fue mayor dentro de las AMP (prueba K­S D  =  0.19, p < 0.0001). La influencia de las características del hábitat sobre el desempeño de las AMP indicó que el ancho de la zona de rompientes está asociado de forma positiva con la abundancia y biomasa de los peces, pero de forma negativa con la riqueza. La región sur tuvo el mayor tamaño de efecto positivo sobre todas las medidas de desempeño de las AMP. Nuestros hallazgos destacan la variabilidad en la riqueza y composición de especies en todas las regiones y los censos que afectan significativamente las diferencias observadas dentro y fuera de las AMP. Una evaluación completa del desempeño de las AMP debe considerar taxones específicos, su distribución y el efecto de los factores de hábitat y la geografía.

2.
J Perinatol ; 42(9): 1266-1270, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35732728

RESUMEN

The knowledge and skills expected for board certification in Neonatal-Perinatal Medicine (NPM) should reflect the clinical practice of neonatology. First, a 14-member panel of practicing neonatologists, convened by the American Board of Pediatrics (ABP), drafted a practice analysis document which identified the practice domains, tasks, knowledge, and skills deemed essential for clinical practice. NPM fellowship program directors provided feedback via online survey resulting in revisions to the document. During the second phase of the project, the panel organized testable knowledge areas into content domains and subdomains to update the existing ABP NPM content outline. All ABP board-certified neonatologists were asked to review via online survey, and results were used to guide final revisions to the content outline. The NPM practice analysis document and the updated NPM content outline should serve as helpful resources for educators, trainees, and practicing neonatologists.


Asunto(s)
Neonatología , Niño , Becas , Humanos , Recién Nacido , Neonatólogos , Encuestas y Cuestionarios , Estados Unidos
3.
Int J Pharm ; 456(1): 175-85, 2013 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-23933439

RESUMEN

Oral delivery of camptothecin has a treatment advantage but is limited by low bioavailability and gastrointestinal toxicity. Poly(amido amine) or PAMAM dendrimers have shown promise as intestinal penetration enhancers, drug solubilizers and drug carriers for oral delivery in vitro and in situ. There have been very limited studies in vivo to evaluate PAMAM dendrimers for oral drug delivery. In this study, camptothecin (5 mg/kg) was formulated and co-delivered with cationic, amine-terminated PAMAM dendrimer generation 4.0 (G4.0) (100 and 300 mg/kg) and anionic, carboxylate-terminated PAMAM generation 3.5 (G3.5) (300 and 1000 mg/kg) in CD-1 mice. Camptothecin associated to a higher extent with G4.0 than G3.5 in the formulation, attributed to an electrostatic interaction on the surface of G4.0. Both PAMAM G4.0 and G3.5 increased camptothecin solubilization in simulated gastric fluid and caused a 2-3 fold increase in oral absorption of camptothecin when delivered at 2 h. PAMAM G4.0 and G3.5 did not increase mannitol transport suggesting that the oral absorption of camptothecin was not due to tight junction modulation. Histologic observations of the epithelial layer of small intestinal segments of the gastrointestinal tract (GIT) at 4 h post dosing supported no evidence of toxicity at the evaluated doses of PAMAM dendrimers. This study demonstrates that both cationic (G.4) and anionic (G3.5) PAMAM dendrimers were effective in enhancing the oral absorption of camptothecin. Results suggest that drug inclusion in PAMAM interior controlled solubilization in simulated gastric and intestinal fluids, and increased oral bioavailability.


Asunto(s)
Antineoplásicos Fitogénicos/farmacocinética , Camptotecina/farmacocinética , Dendrímeros/farmacocinética , Portadores de Fármacos/farmacocinética , Administración Oral , Animales , Antineoplásicos Fitogénicos/administración & dosificación , Antineoplásicos Fitogénicos/química , Disponibilidad Biológica , Camptotecina/administración & dosificación , Camptotecina/química , Dendrímeros/administración & dosificación , Dendrímeros/química , Portadores de Fármacos/administración & dosificación , Portadores de Fármacos/química , Femenino , Absorción Intestinal , Intestino Delgado/efectos de los fármacos , Intestino Delgado/ultraestructura , Ratones , Microscopía Electrónica de Transmisión
4.
Drug Deliv Transl Res ; 3(3): 260-271, 2013 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-23795337

RESUMEN

The purpose of this study was to model data from a head to head comparison of the in vivo fate of hyper-branched PAMAM dendrimers with linear HPMA copolymers in order to understand the influence of molecular weight (MW), hydrodynamic size (Rh) and polymer architecture on biodistribution in tumor-bearing mice using compartmental pharmacokinetic analysis. Plasma concentration data was modeled by two-compartment analysis using Winnonlin® to obtain elimination clearance (E.CL) and plasma exposure (AUCplasma). Renal clearance (CLR) was calculated from urine data collected over 1 week. A plasma-tumor link model was fitted to experimental plasma and tumor data by varying the tumor extravasation (K4, K6) and elimination (K5) rate constants using multivariable constrained optimization solver in Matlab®. Tumor exposures (AUCtumor) were computed from area under the tumor concentration time profile curve by the linear trapezoidal method. Along with MW and Rh, polymer architecture was critical in affecting the blood and tumor pharmacokinetics of the PAMAM-OH dendrimers and HPMA copolymers. Elimination clearance decreased more rapidly with increase in hydrodynamic size for PAMAM-OH dendrimers as compared to HPMA copolymers. HPMA copolymers were eliminated renally to a higher extent than PAMAM-OH dendrimers. These results are suggestive of a difference in extravasation of polymers of varying architecture through the glomerular basement membrane. While the linear HPMA copolymers can potentially reptate through a pore smaller in size than their hydrodynamic radii in a random coil conformation, PAMAM dendrimers have to deform in order to permeate across the pores. With increase in molecular weight or generation, the deforming capacity of PAMAM-OH dendrimers is known to decrease, making it harder for higher generation PAMAM-OH dendrimers to sieve through the glomerulus as compared to HPMA copolymers of comparable molecular weights. PAMAM-OH dendrimer had greater tumor extravsation rate constants and higher tumor to plasma exposure ratios than HPMA copolymers of comparable molecular weights which indicated that in the size range studied, when in circulation, PAMAM-OH dendrimers had a higher affinity to accumulate in the tumor than the HPMA copolymers.

5.
Placenta ; 31(8): 665-74, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20598369

RESUMEN

Preterm birth continues to be a growing problem in the USA. Although approximately half of preterm births are caused by intrauterine infection, uterine over-distension is also a cause. In this study we have compared the effects of static stretch, cyclic stretch/release and an inflammatory stimulus alone and in combination on the expression of Pre-B cell colony-enhancing factor (PBEF) and IL-8 in primary amniotic epithelial cells (AEC). We then sought to identify some of the mechanism(s) by which these cells respond to stretching stimuli. We show that cyclic stretch/release is a more robust stimulus for both PBEF and IL-8 than static stretch. Cyclic stretch/release increased both intracellular and secreted PBEF and a combination of both types of stretch was a more robust stimulus to PBEF that IL-8. However, when an inflammatory stimulus (IL-1beta) was added to either kind of stretch, the effect on IL-8 was much greater than that on PBEF. Thus, different kinds of stretch affect the expression of these two cytokines from AEC, but inflammation is a much stronger stimulus of IL-8 than PBEF, agreeing with its primary role as a chemokine. Although the AEC showed morphological signs of increased cellular stress during stretching, blocking reactive oxygen species (ROS) had little effect. However, blocking integrin binding to fibronectin significantly reduced the responses of both PBEF and IL-8 to cyclic stretch/release. The increased PBEF, both intracellularly and secreted, suggests that it functions both to increase the metabolism of the cells, at the same time as stimulating further the cytokine cascade leading to parturition.


Asunto(s)
Amnios/metabolismo , Citocinas/metabolismo , Inflamación/metabolismo , Interleucina-8/metabolismo , Nicotinamida Fosforribosiltransferasa/metabolismo , Estrés Mecánico , Células Cultivadas , Células Epiteliales/metabolismo , Femenino , Expresión Génica , Humanos , Integrinas/metabolismo , Mecanotransducción Celular , Embarazo , Nacimiento Prematuro/etiología , Especies Reactivas de Oxígeno/metabolismo , Regulación hacia Arriba
6.
Placenta ; 29(3): 255-65, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18272217

RESUMEN

In normal pregnancy, the fetal membranes become increasingly distended towards term and in multifetal gestations they become over-distended. Apoptosis of the amniotic epithelium increases with advancing gestation and may contribute to fetal membrane weakening and rupture. The effects of chronic static stretching for 36h have been investigated using primary amniotic epithelial cells. Pre-B cell colony-enhancing factor (PBEF) is a stretch-responsive cytokine and expression of its gene, intracellular and secreted protein were all significantly increased by 4h and its secretion sustained over 36h, contrasting with the rapid increase and decline in expression of IL-8. Increased expression of SIRT1 and decreased p53 paralleled the changes in PBEF, are known to be responsive to PBEF, and contribute to cell survival. Distension had no effects on proliferation or necrosis but protected the cells from apoptosis, knocking-down PBEF with antisense probes abrogated this protective effect. There was increased immunostaining of PBEF in the compact layer of the amnion in multifetal tissues and significantly fewer apoptotic amniotic epithelial cells. These results show that chronic stretching of the amniotic epithelial cells increases PBEF expression, which protects them from apoptosis.


Asunto(s)
Amnios/fisiología , Apoptosis/genética , Citocinas/genética , Células Epiteliales/metabolismo , Células Epiteliales/fisiología , Nicotinamida Fosforribosiltransferasa/genética , Amnios/crecimiento & desarrollo , Amnios/metabolismo , Células Cultivadas , Citocinas/metabolismo , Citoprotección/genética , Elasticidad , Femenino , Regulación de la Expresión Génica , Humanos , Nicotinamida Fosforribosiltransferasa/metabolismo , Embarazo , Embarazo Múltiple/genética , Embarazo Múltiple/metabolismo , Sirtuina 1 , Sirtuinas/metabolismo , Estrés Mecánico , Resistencia a la Tracción/fisiología , Trillizos , Proteína p53 Supresora de Tumor/metabolismo , Gemelos
7.
Neuroscience ; 150(4): 818-28, 2007 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-17988803

RESUMEN

The basolateral amygdala complex (BLA) and central amygdala nucleus (CeA) are involved in fear and anxiety. In addition, the BLA contains a high density of corticotropin-releasing factor 1 (CRF(1)) receptors in comparison to the CeA. However, the role of BLA CRF(1) receptors in contextual fear conditioning is poorly understood. In the present study, we first demonstrated in rats that oral administration of DMP696, the selective CRF(1) receptor antagonist, had no significant effects on the acquisition of contextual fear but produced a subsequent impairment in contextual freezing suggesting a role of CRF(1) receptors in the fear memory consolidation process. In addition, oral administration of DMP696 significantly reduced phosphorylation of cyclic AMP response element-binding protein (pCREB) in the lateral and basolateral amygdala nuclei, but not in the CeA, during the post-fear conditioning period. We then demonstrated that bilateral microinjections of DMP696 into the BLA produced no significant effects on the acquisition of conditioned fear but reduced contextual freezing in a subsequent drug-free conditioned fear test. Importantly, bilateral microinjections of DMP696 into the BLA at 5 min or 3 h, but not 9 h, after exposure to contextual fear conditioning was also effective in reducing contextual freezing in the conditioned fear test. Finally, microinfusions of either DMP696 into the CeA or a specific corticotropin-releasing factor 2 receptor antagonist in the BLA were shown to have no major effects on disrupting either contextual fear conditioning or performance of contextual freezing in the drug-free conditioned fear test. Collectively, results implicate a role of BLA CRF(1) receptors in activating the fear memory consolidation process, which may involve BLA pCREB-induced synaptic plasticity.


Asunto(s)
Amígdala del Cerebelo/metabolismo , Condicionamiento Clásico/fisiología , Hormona Liberadora de Corticotropina/metabolismo , Miedo , Amígdala del Cerebelo/efectos de los fármacos , Animales , Animales Recién Nacidos , Conducta Animal/efectos de los fármacos , Proteína de Unión a CREB/metabolismo , Condicionamiento Clásico/efectos de los fármacos , Hormona Liberadora de Corticotropina/antagonistas & inhibidores , Relación Dosis-Respuesta a Droga , Electrochoque/efectos adversos , Reacción Cataléptica de Congelación/efectos de los fármacos , Masculino , Dimensión del Dolor , Pirazoles/farmacología , Ratas , Ratas Long-Evans , Tiempo de Reacción/efectos de los fármacos , Factores de Tiempo , Triazinas/farmacología
8.
Physiol Behav ; 80(4): 525-30, 2004 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-14741237

RESUMEN

Laboratory rats show a range of defensive behaviors, including freezing, avoidance, and risk assessment upon exposure to cat odor, an unconditioned but highly effective threat stimulus. This study examined defensive behaviors, and the rapid conditioning to context plus cue, of these behaviors, in 18-, 26-, and 38-day-old male and female rats exposed to cat odor. Rats were placed individually in a runway with a cloth covered (control or saturated with cat fur/skin odor) block for a 10-min trial. On the following day, a similar trial involved an odorless block. On the odor exposure day, rats of all ages showed less contact with the odor block than with the control block. The 26- and 38-day-old rats, but not the 18-day-old rats, also showed locomotor suppression, more avoidance of the area where the odor block was located, and more risk assessment than no-odor controls. On a test of conditioned behavior 24 h following exposure, 26- and 38-day-old rats exhibited defensive behavior including avoidance and reduction of locomotion while 18-day-old pups did not.


Asunto(s)
Reacción de Prevención/fisiología , Conducta Animal/fisiología , Condicionamiento Psicológico/fisiología , Miedo/fisiología , Odorantes , Factores de Edad , Animales , Gatos , Señales (Psicología) , Femenino , Masculino , Conducta Predatoria/fisiología , Distribución Aleatoria , Ratas , Ratas Long-Evans , Riesgo , Factores Sexuales
9.
Clin Microbiol Infect ; 8(4): 214-21, 2002 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-12047413

RESUMEN

OBJECTIVE: To assess the activities of levofloxacin and the comparator agents erythromycin, clarithromycin, azithromycin and doxycycline against atypical respiratory pathogens. METHODS: One hundred and forty-six Legionella pneumophila, 41 Mycoplasma pneumoniae and nine Chlamydia pneumoniae isolates were procured from various culture collections in North America and Europe and tested for susceptibility to the above agents by broth microdilution. The isolates came primarily from clinical sources and were collected from patients between 1995 and 1999. RESULTS: Against L. pneumophila, levofloxacin was the most active agent, with an MIC(90) of 0.03 mg/L, twofold more active than clarithromycin (0.06 mg/L), 16-fold more active than erythromycin and azithromycin (0.5 mg/L) and 64-fold more active than doxycycline. Against M. pneumoniae, azithromycin (MIC(90) < or = 0.0005 mg/L) was the most active agent. However, two isolates of M. pneumoniae, one from the USA and one from Finland, were macrolide resistant (MIC > or = 4 mg/L), but levofloxacin susceptible (MIC 0.25 mg/L). The geographic origin of L. pneumophila and M. pneumoniae did not affect the MIC range for any antimicrobial agent tested. Against C. pneumoniae, clarithromycin was the most active agent, with an MIC range of < or =0.008-0.03 mg/L. CONCLUSIONS: Levofloxacin had comparable activity to the other agents tested against the atypical respiratory pathogens, confirming its potential as an alternative for empirical therapy of community-acquired pneumonia.


Asunto(s)
Antiinfecciosos/farmacología , Chlamydophila pneumoniae/efectos de los fármacos , Farmacorresistencia Bacteriana , Legionella pneumophila/efectos de los fármacos , Levofloxacino , Mycoplasma pneumoniae/efectos de los fármacos , Ofloxacino/farmacología , Antibacterianos/farmacología , Chlamydophila pneumoniae/fisiología , Doxiciclina/farmacología , Europa (Continente) , Humanos , Legionella pneumophila/fisiología , Macrólidos , Pruebas de Sensibilidad Microbiana , Mycoplasma pneumoniae/fisiología , América del Norte
11.
Drug Metab Dispos ; 28(12): 1464-9, 2000 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11095584

RESUMEN

The relationship between xenobiotic concentrations in hair and the degree of systemic xenobiotic exposure is poorly defined. The purpose of this study was to evaluate the effect of dose, time, and pigment on the hair incorporation of cocaine (COC) and its metabolites, benzoylecgonine (BE), ecgonine methyl ester (EME), and norcocaine (NCOC). COC was administered by the i.p. route to male Long-Evans (LE) rats at three doses (5, 10, and 20 mg/kg) once daily for 5 days. Fourteen days after the initial injection, the hair was collected and analyzed by gas chromatography/mass spectrometry for the compounds of interest. COC, EME, and NCOC were preferentially incorporated into pigmented hair in a dose-dependent manner. None of the analytes were detected in nonpigmented hair. The plasma pharmacokinetic profile of each analyte was determined at each dose. After normalizing for the plasma concentrations, the incorporation of COC into pigmented hair was 2 orders of magnitude greater than BE. The time course of COC and metabolite distribution into hair was also investigated from 1 h to 14 days after a single dose. After COC disappears from plasma, there is a 3-day delay before maximal hair concentrations are reached in pigmented hair. In nonpigmented hair, concentrations of BE and COC did not exceed 0.25 ng/mg and were undetectable after 4 h and 2 days, respectively. This study demonstrates that the pigment-mediated differences in the incorporation of COC and its metabolites noted at 14 days after dosing are also evident a few hours after drug administration.


Asunto(s)
Cocaína/farmacocinética , Inhibidores de Captación de Dopamina/farmacocinética , Color del Cabello/fisiología , Cabello/metabolismo , Animales , Área Bajo la Curva , Biotransformación , Cocaína/administración & dosificación , Cocaína/sangre , Inhibidores de Captación de Dopamina/administración & dosificación , Inhibidores de Captación de Dopamina/sangre , Relación Dosis-Respuesta a Droga , Cromatografía de Gases y Espectrometría de Masas , Masculino , Ratas , Ratas Long-Evans
12.
Am J Health Promot ; 14(3): 170-3, iii, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-10787769

RESUMEN

A convenience sample of 99 questionnaire respondents was used to develop an instrument to measure "cues to action" for health-promoting behaviors. The questionnaire contained 32 items producing an alpha coefficient of 0.88. Because of the small sample size and limitations of the convenience sample, the authors recommend that their findings be considered preliminary.


Asunto(s)
Señales (Psicología) , Conductas Relacionadas con la Salud , Psicometría/métodos , Encuestas y Cuestionarios , Adulto , Anciano , Anciano de 80 o más Años , Análisis de Varianza , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Sudoeste de Estados Unidos
13.
J Athl Train ; 35(1): 103-7, 2000 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16558600

RESUMEN

OBJECTIVE: To present the case of a 22-year-old football player who sustained an acute posterior-wall acetabular fracture. BACKGROUND: Acetabular fractures can be a difficult injury for the athletic trainer to assess. Aside from the obvious immediate ramifications, proper assessment and care are necessary to decrease the chance of developing posttraumatic arthritis and other long-term complications. DIFFERENTIAL DIAGNOSIS: Anterior column fracture, T-shaped acetabular fracture, segmental fracture of the femoral head, femoral neck fracture, capsular tear, retroperitoneal hematoma, posterior column acetabular fracture. TREATMENT: The athlete was treated with open reduction internal fixation using 5 screws and a plate. He pursued a rehabilitation program and returned to full activity 9 months later. UNIQUENESS: Acetabular fractures are usually associated with motor vehicle accidents. However, this athlete sustained an injury mechanism that rarely occurs in athletes. CONCLUSIONS: Certified athletic trainers need to recognize the signs and symptoms associated with acetabular fractures. Initial recognition and appropriate management and treatment are essential to avoid long-term complications.

14.
Appl Psychophysiol Biofeedback ; 24(1): 41; discussion 43-54, 1999 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10553482

RESUMEN

The definition proposed by Mark Schwartz is discussed in brief fashion and is found to be very useful and appropriate.


Asunto(s)
Psicofisiología , Humanos , Semántica
15.
Anal Chem ; 71(14): 2607-15, 1999 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-10424158

RESUMEN

In-vivo and in-vitro investigations indicate that a newly developed polyazamacrocyclic chelate of Tb(III) has superior properties for use as an abnormal tissue marker. In addition to tissue selectivity, this molecule is unique because of its low toxicity, attractive fluorescent properties, rapid pharmokinetics, and relatively high water solubility. The complex Tb-3,6,9-tris(methylene phosphonic acid n-butyl ester)-3,6,9,15-tetraazabicyclo[9.3.1]-pentadeca-1(15),11,13 -triene (Tb-PCTMB) has also been shown to exhibit strongly shifted emission (delta lambda--280 nm), moving the detection frequency away from autofluorescence backgrounds, and good quantum efficiencies (phi = 0.51), providing high brightness. Fluorescence imaging was used to quantify Tb-PCTMB at the picomolar level in tissues and to show the significant difference in affinity for the chelate by adenocarcinoma cells HT-29 versus normal epithelial cells (IEC-6). Topical application, or lavage introduction, under endoscopy was used to instill a millimolar aqueous solution of Tb-PCTMB into a dimethylhydrizene-treated Sprague Dawley rat large intestine containing a suspect growth. Subsequent in vitro fluorescence detection and standard histological evaluation confirmed enhanced uptake by adenocarcinoma tissue. Semiquantitative signal interrogation was employed to show the potential for using Tb-PCTMB as a contrast enhancement marker for disease detection.


Asunto(s)
Quelantes , Neoplasias/diagnóstico por imagen , Compuestos Organometálicos , Animales , Supervivencia Celular , Humanos , Microscopía Fluorescente , Neoplasias/patología , Radiografía , Ratas , Ratas Sprague-Dawley , Células Tumorales Cultivadas
16.
J Anal Toxicol ; 22(6): 414-7, 1998 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9788514

RESUMEN

Hair pigmentation is a critical factor in the interpretation of the concentration of certain compounds and their metabolites incorporated into hair. Melanin is responsible for the pigmentation. The color and the melanin content of human hair samples differs over a wide range. Once deposited into hair, drug may remain detectable for a period of months to years. However, if drug disposition into hair is influenced by those properties attributed to hair color, then certain persons may test positive more frequently than other persons. Removal of the melanin from hair digests prior to drug analysis may reduce the effect of melanin on the total drug concentration by excluding the drug bound to the pigment. In this study, the effect of melanin removal by centrifugation of hair digests on cocaine concentrations was investigated. Two sets of hair samples from five cocaine users were analyzed for cocaine and metabolites. A solution consisting of 10 mL of 0.5M Tris buffer (pH 6.4) to which is added 60 mg D,L-dithiothreitol, 200 mg SDS, and 200 U Proteinase K, was used to digest the hair. Two milliliters of this solution was added to 20 mg of hair and incubated at 37 degrees in a shaking water bath (90 oscillations/min) overnight. The samples were removed from the water bath and mixed. One set was centrifuged at 2000 rpm and divided into supernatant and melanin pellet. The other set was not centrifuged. Internal standards were added to all tubes. The samples were further extracted, derivatized, and analyzed by gas chromatography-mass spectrometry. A mean of 8.8% (standard deviation [SD] 7.0%) of the total cocaine concentration (supernatant and pellet) was left behind in the pellet. The same experiment was repeated except that the melanin pellet was redigested with 0.1 N HCl. After redigestion of the melanin pellet, the mean cocaine concentration in the pellet was 3.8% +/- 4.0% (mean +/- SD) of the total cocaine concentration in hair. These data demonstrate that removal of melanin from hair digests by centrifugation does not eliminate hair color bias when interpreting cocaine concentrations.


Asunto(s)
Trastornos Relacionados con Cocaína/diagnóstico , Cocaína/análisis , Cabello/química , Detección de Abuso de Sustancias/métodos , Centrifugación , Cromatografía de Gases y Espectrometría de Masas , Color del Cabello , Humanos , Melaninas/química
17.
Otolaryngol Head Neck Surg ; 118(1): 69-73, 1998 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9450831

RESUMEN

Eighty-two children underwent polysomnography (PSG) for symptoms suggestive of obstructive sleep apnea (OSA). Symptoms reported included snoring, witnessed apneic episodes, daytime somnolence, mouth breathing, and enuresis. Tonsillar size, nasal airway patency, and percentile weight were recorded. OSA was diagnosed on PSG when obstructive events were noted and apnea + hypopnea index was five or more per hour. The overall predictive accuracy of clinical suspicion of OSA was 25 (30%) of 82. Predictive accuracies (as a percentage of those with symptoms/signs who have OSA) and prevalences (as a percentage of those with OSA who have the symptom/sign), respectively, were for moderate snoring 29% (12 of 41), 48%; loud snoring 31% (11 of 35), 44%; witnessed apneas 32% (22 of 69), 88%; enuresis 46% (11 of 24), 44%; 2+ tonsillar size 37% (21 of 57), 84%; 3+ tonsillar size 33% (3 of 9), 12%; 90th percentile weight or greater 26% (7 of 27), 28%; 10th percentile weight or less 33% (5 of 15), 20%. Multiple regression analysis did not reveal a significant association between clinical parameters and the presence of OSA as defined by PSG.


Asunto(s)
Síndromes de la Apnea del Sueño/diagnóstico , Adolescente , Niño , Preescolar , Enuresis/etiología , Femenino , Humanos , Lactante , Modelos Logísticos , Masculino , Polisomnografía , Estudios Retrospectivos , Síndromes de la Apnea del Sueño/complicaciones , Ronquido/etiología
18.
J Biomed Opt ; 3(2): 145-53, 1998 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23015051

RESUMEN

Tissue spectroscopy and endoscopy are combined with a tissue site-selective fluorescent probe molecule to demonstrate in vitro, spatial, remote, quantitative imaging of the rat small intestine. The probe molecule employed, Tb-3,6,9-tris(methylene phosphonic acid n-butyl ester)-3,6,9,15-tetraaza-bicyclo[9.3.1]pentadeca-1(15),11,13-triene (Tb-PCTMB), is shown to bind with the small intestine and provide improved image contrast. High sensitivity is possible due to the absorption-emission Stokes's shift exhibited by the Tb-PTCMB complex. Excitation is centered near 270 nm and multifeatured emission is observed at 490, 550, 590, and 625 nm. Sprague-Dawley rats were dosed with the Tb-PTCMB complex, which shows biodistribution, leading to preferential binding to the inner surface of the small intestine. It is shown that the fluorescent image, taken at 550 nm, can be used to quantify the amount of Tb-PCTMB present in an excised tissue sample. The 3σ detection limits are found to be in the femtomole range. An optical mass balance for Tb-PCTMB-dosed small intestine is performed and along with radiotracer biodistribution, demonstrates that approximately 40% of the marker probe resides in the endothelial tissue of the small intestine inner lumen. This result is of particular interest since most adult colon cancers develop in this region. These results demonstrate the ability to perform spatial, quantitative, in vitro, endoscopic imaging of a complex biological sample using a probe marker. © 1998 Society of Photo-Optical Instrumentation Engineers.

19.
Pain ; 69(1-2): 65-73, 1997 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9060014

RESUMEN

The myofascial trigger point (MTrP) is the hallmark physical finding of the myofascial pain syndrome (MPS). The MTrP itself is characterized by distinctive physical features that include a tender point in a taut band of muscle, a local twitch response (LTR) to mechanical stimulation, a pain referral pattern characteristic of trigger points of specific areas in each muscle, and the reproduction of the patient's usual pain. No prior study has demonstrated that these physical features are reproducible among different examiners, thereby establishing the reliability of the physical examination in the diagnosis of the MPS. This paper reports an initial attempt to establish the interrater reliability of the trigger point examination that failed, and a second study by the same examiners that included a training period and that successfully established interrater reliability in the diagnosis of the MTrP. The study also showed that the interrater reliability of different features varies, the LTR being the most difficult, and that the interrater reliability of the identification of MTrP features among different muscles also varies.


Asunto(s)
Síndromes del Dolor Miofascial/diagnóstico , Adulto , Anciano , Músculos Faciales/inervación , Músculos Faciales/fisiopatología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Síndromes del Dolor Miofascial/fisiopatología , Variaciones Dependientes del Observador , Dimensión del Dolor , Estimulación Física , Esposos/psicología
20.
Mutat Res ; 363(3): 201-8, 1996 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-8765161

RESUMEN

Survival after gamma irradiation (generated from either a 137Cs or 60Co source) was determined for two strains of the nematode Caenorhabditis elegans. Animals were between 1.3 and 39 times more sensitive to cesium than to cobalt. The magnitude of this differential sensitivity was dependent upon the strain, developmental stage and sex tested. Several control experiments eliminated trivial explanations for this difference. Since cobalt- and cesium-generated gamma particles have nearly identical energy depositions, the differential sensitivity likely reflects different mechanisms of processing the slightly different spectra of DNA damage induced by these two radiations. Sex-specific differences in radiation sensitivity were also noted and were likely due to the fact that males possess a single X chromosome rather than two, as do hermaphrodites.


Asunto(s)
Caenorhabditis elegans/efectos de la radiación , Radioisótopos de Cesio , Radioisótopos de Cobalto , Tolerancia a Radiación , Animales , Caenorhabditis elegans/crecimiento & desarrollo , Relación Dosis-Respuesta en la Radiación , Factores Sexuales
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