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1.
Ophthalmology ; 131(5): 611-621, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38086435

RESUMEN

PURPOSE: Vision screening and regular eye care can help detect and treat potentially irreversible vision impairment. This study aims to investigate the associations between sociodemographic and health characteristics and the receipt of eye care among children aged 17 years and younger in the United States. DESIGN: This cross-sectional study used data from the National Survey of Children's Health (NSCH), a nationally representative and population-based survey of randomly sampled households. PARTICIPANTS: Participants were children aged 0 to 17 years, residing in all 50 states and the District of Columbia, whose caregivers or parents answered an address-based survey by mail or online. METHODS: Weighted prevalence calculations were applied to analyze the data, and logistic regression was performed to explore associations between reported eye care and demographic, health, and parent-related variables. MAIN OUTCOME MEASURES: Caregiver-reported vision screenings, referral to an eye doctor after vision screening, eye doctor visits, and prescription of corrective lenses. RESULTS: Caregivers reported that 53.2% of children had a vision screening at least once (if child ≤ 5 years) or within the past 2 years (if child > 5 years). Of those screened, 26.9% were referred to an eye doctor. Overall, 38.6% of all children had a previous eye doctor visit, and among them, 55.4% were prescribed corrective lenses during the visit. Factors associated with decreased odds of vision screening included younger age, lack of health care visits, no insurance coverage, parent education high school or less, and lower household income. Non-White ethnicities, households with a non-English primary language, and lower incomes were more likely to be referred to an eye doctor after vision screening. Lower rates of eye doctor visits were associated with younger age, lack of insurance coverage, and primary household languages other than English. CONCLUSIONS: Children from disadvantaged backgrounds are less likely to receive vision screening and eye care. Targeted strategies are needed to increase vision screening and access to eye care services in these vulnerable groups. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found after the references.

2.
Br J Dermatol ; 186(3): 553-563, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34726260

RESUMEN

BACKGROUND: Epithelioid haemangioma (EH) arising from the skin is a benign vascular tumour with marked inflammatory cell infiltration, which exhibits a high tendency to persist and frequently recurs after resection. So far, the underlying pathogenesis is largely elusive. OBJECTIVES: To identify genetic alterations by next-generation sequencing and/or droplet digital polymerase chain reaction (ddPCR) in cutaneous EH. METHODS: DNA and RNA from an EH lesion of an index patient were subjected to whole-genome and RNA sequencing. Multiplex PCR-based panel sequencing of genomic DNA isolated from archival formalin-fixed paraffin-embedded tissue of 18 patients with cutaneous EH was performed. ddPCR was used to confirm mutations. RESULTS: We identified somatic mutations in genes of the mitogen-activated protein kinase (MAPK) pathway (MAP2K1 and KRAS) in cutaneous EH biopsies. By ddPCR we could confirm the recurrent presence of activating, low-frequency mutations affecting MAP2K1. In total, nine out of 18 patients analysed showed activating MAPK pathway mutations, which were mutually exclusive. Comparative analysis of tissue areas enriched for lymphatic infiltrate or aberrant endothelial cells, respectively, revealed an association of these mutations with the presence of endothelial cells. CONCLUSIONS: Taken together, our data suggest that EH shows somatic mutations in genes of the MAPK pathway which might contribute to the formation of this benign tumour.


Asunto(s)
Hemangioma , Neoplasias Cutáneas , ADN , Células Endoteliales , Hemangioma/genética , Humanos , Proteínas Quinasas Activadas por Mitógenos/genética , Reacción en Cadena de la Polimerasa Multiplex , Mutación/genética , Recurrencia Local de Neoplasia , Neoplasias Cutáneas/genética
3.
Eur J Nucl Med Mol Imaging ; 48(4): 1178-1187, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33057927

RESUMEN

PURPOSE: In cancer of unknown primary (CUP), positron emission tomography/computed tomography (PET/CT) with the glucose analog [18F]FDG represents the standard imaging approach for localization of the malignant primary. Frequently, however, [18F]FDG PET/CT cannot precisely distinguish between small occult tumors and chronic inflammation, especially in Waldeyer's tonsillar ring. To improve the accuracy for detecting primary tumors in the Waldeyer's tonsillar ring, the novel PET tracer [68Ga]Ga-FAPI-4 for specific imaging of fibroblast activation protein (FAP) expression was used as a more specific target for cancer imaging. METHODS: Eight patients with suspicion of a malignant tumor in Waldeyer's tonsillar ring or a CUP syndrome were examined. PET/CT scans with [18F]-FDG and [68Ga]Ga-FAPI-4 were performed for pre-operative tumor localization. After surgical resection, histopathological and immunohistochemical results were compared to PET/CT findings. RESULTS: Histopathology revealed a palatine or lingual tonsil carcinoma in all patients. In case of lymph node metastases smaller than 7 mm in size, the [18F]FDG PET/CT detection rate of cervical lymph node metastases was higher than that of [68Ga]FAPI PET/CT, while both tracers identified the primary tumors in all eight cases. The size of the primary and the lymph node metastases was directly correlated to the respective FAP expression, as detected by immunohistochemistry. The mean SUVmax for the primary tumors was 21.29 ± 7.97 for 18F-FDG and 16.06 ± 6.29 for 68Ga-FAPI, respectively (p = 0.2). The mean SUVmax for the healthy contralateral tonsils was 8.38 ± 2.45 for [18F]FDG and 3.55 ± 0.47 for [68Ga]FAPI (p < 0.001). The SUVmax ratio of [68Ga]FAPI was significantly different from [18F] FDG (p = 0.03). Mean TBRmax for the [68Ga]Ga-FAPI-4 tracer was markedly higher in comparison to [18F]FDG (10.90 vs. 4.11). CONCLUSION: Non-invasive imaging of FAP expression by [68Ga]FAPI PET/CT resulted in a better visual detection of the malignant primary in CUP, as compared to [18F]FDG imaging. However, the detection rate of lymph node metastases was inferior, presumably due to low FAP expression in small metastases. Nevertheless, by offering a detection method for primary tumors with the potential of lower false positive rates and thus avoiding biopsies, patients with CUP syndrome may benefit from [68Ga]FAPI PET/CT imaging.


Asunto(s)
Neoplasias Primarias Desconocidas , Tomografía Computarizada por Tomografía de Emisión de Positrones , Fluorodesoxiglucosa F18 , Radioisótopos de Galio , Humanos , Ganglios Linfáticos , Neoplasias Primarias Desconocidas/diagnóstico por imagen
4.
Langmuir ; 34(15): 4695-4700, 2018 04 17.
Artículo en Inglés | MEDLINE | ID: mdl-29510056

RESUMEN

It is shown that introducing gravity in the energy minimization of drops on surfaces results in different expressions when minimized with respect to volume or with respect to contact angle. This phenomenon correlates with the probability of drops to bounce on smooth surfaces on which they otherwise form a very small contact angle or wet them completely. Theoretically, none of the two minima is stable: the drop should oscillate from one minimum to the other as long as no other force or friction will dissipate the energy. Experimentally, smooth surfaces indeed show drops that bounce on them. In some cases, they bounce after touching the solid surface, and in some cases they bounce from a nanometric air, or vacuum film. The bouncing energy can be stored in the interfaces: liquid-air, liquid-solid, and solid-air. The lack of a single energy minimum prevents a simple convergence of the drop's shape on the solid surface, and supports its bouncing back to the air. Therefore, the lack of a simple minimum described here supports drop bouncing on hydrophilic surfaces such as that reported by Kolinski et al. Our calculation shows that the smaller the surface tension, the bigger the difference between the contact angles calculated based on the two minima. This agrees with experimental finding where reducing the surface tension, for example, by adding surfactants, increases the probability for bouncing of the drops on smooth surfaces.

5.
Dev Med Child Neurol ; 58(2): 154-9, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26084944

RESUMEN

AIM: To assess motor functioning in children aged 4 years 6 months enrolled in the Infant Aphakia Treatment Study, and to determine contributions of visual acuity and stereopsis to measured motor skills. METHOD: One hundred and four children (53% female) with unilateral aphakia randomized to intraocular lens or contact lens treatment were evaluated at 4 years 6 months (age range 4y 6mo-4y 11mo) for monocular recognition visual acuity, motor skills, and stereopsis by a traveling examiner masked to treatment condition. Motor skills were assessed with the Movement Assessment Battery for Children--Second Edition (MABC-2). Visual acuity was operationalized as log10 of the minimum angle of resolution (logMAR) value for treated eye, best logMAR value for either eye, and intraocular logMAR difference. RESULTS: Student's t-tests showed no significant differences in MABC-2 scores between the intraocular lens and contact lens groups. The mean total score was low (6.43; 18th centile) compared with the normative reference group. Motor functioning was not related to visual acuity in the treated eye or to intraocular logMAR difference, but was predicted in a regression model by the better visual acuity of either eye (usually the fellow eye), even after accounting for the influence of age at surgery, examiner, orthotropic ocular alignment, and stereopsis. INTERPRETATION: Children with unilateral congenital cataract may have delayed motor functioning at 4 years 6 months, which may adversely affect their social and academic functioning.


Asunto(s)
Afaquia/fisiopatología , Desarrollo Infantil/fisiología , Destreza Motora/fisiología , Trastornos de la Visión/fisiopatología , Agudeza Visual/fisiología , Afaquia/complicaciones , Afaquia/congénito , Preescolar , Percepción de Profundidad/fisiología , Femenino , Humanos , Masculino , Trastornos de la Visión/etiología , Visión Monocular/fisiología
6.
J Dairy Res ; 83(2): 173-9, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-27056664

RESUMEN

Milk with a high concentration of fat and casein is required for cheese production, and these components have a major impact for both quality and yield of the curd. Recent observations have shown that suckling can elevate milk fat concentration in goats and our aim was therefore to check the hypothesis that animal welfare and cheese-processing properties of goat milk could be optimised by appropriate management of suckled/milked goats. Twelve Swedish dairy goats were kept together with one kid each in 4 different mixed management-systems (milking combined with partial suckling) in a cross-over design. Two milk accumulation intervals were tested; Short = dams and kids were together for 16 h (T16) and Long = ; dams and kids were together for 8 h (T8 h). In addition, two milking regimes were used; Suckled Before Milking = S and Milked Before Suckling = M. Milk accumulation interval referred to how long dams and kids were separated. The milk yield available for processing (milk offtake), was weighed and analysed from each milking occasion and the suckled milk yield was estimated by a weigh-suckle-weigh method (WSW) in combination with observing the suckling behaviour during the free suckling periods. Milking managements, such as 'suckling before milking (S)', increased milk fat concentration compared to milking before suckling (M) and 'Short accumulation treatments (T16)' gave higher milk fat, casein concentration and individual curd yield (%) compared to the 'Long accumulation treatment (T8)'. The total individual curd yield (g) was the same despite treatment, but the animal welfare was most likely higher in T16 where dams and kids spent more time together.


Asunto(s)
Industria Lechera/métodos , Cabras , Lactancia , Leche , Animales , Caseínas/análisis , Recuento de Células , Queso , Grasas/análisis , Femenino , Manipulación de Alimentos/métodos , Concentración de Iones de Hidrógeno , Leche/química , Leche/citología , Conducta en la Lactancia , Suecia
7.
Anaesthesia ; 70(10): 1171-9, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26179167

RESUMEN

Novel devices for small-lumen ventilation may enable effective inspiration and expiratory ventilation assistance despite airway obstruction. In this study, we investigated a porcine model of complete upper airway obstruction. After ethical approval, we randomly assigned 13 anaesthetised pigs either to small-lumen ventilation following airway obstruction (n = 8) for 30 min, or to volume-controlled ventilation (sham setting, n = 5). Small-lumen ventilation enabled adequate gas exchange over 30 min. One animal died as a result of a tension pneumothorax in this setting. Redistribution of ventilation from dorsal to central compartments and significant impairment of the distribution of ventilation/perfusion occurred. Histopathology demonstrated considerable lung injury, predominantly through differences in the dorsal dependent lung regions. Small-lumen ventilation maintained adequate gas exchange in a porcine airway obstruction model. The use of this technique for 30 min by inexperienced clinicians was associated with considerable end-expiratory collapse leading to lung injury, and may also carry the risk of severe injury.


Asunto(s)
Obstrucción de las Vías Aéreas/terapia , Respiración Artificial/métodos , Lesión Pulmonar Aguda/etiología , Obstrucción de las Vías Aéreas/sangre , Obstrucción de las Vías Aéreas/fisiopatología , Animales , Modelos Animales de Enfermedad , Hemodinámica/fisiología , Masculino , Oxígeno/sangre , Presión Parcial , Intercambio Gaseoso Pulmonar/fisiología , Respiración Artificial/efectos adversos , Sus scrofa , Volumen de Ventilación Pulmonar/fisiología , Traqueotomía/métodos
8.
Optom Vis Sci ; 92(1): 24-30, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25562478

RESUMEN

PURPOSE: This article provides a rationale for developing an integrated data system for recording vision screening and eye care follow-up outcomes in preschool-aged children. The recommendations were developed by the National Expert Panel to the National Center for Children's Vision and Eye Health at Prevent Blindness and funded by the Maternal and Child Health Bureau of the Health Resources and Services Administration, US Department of Health and Human Services. Guidance is provided regarding specific elements to be included, as well as the characteristics and architecture of such a data system. Vision screening for preschool-aged children is endorsed by many organizations concerned with children's health issues. Currently, there is a lack of data on the proportion of children screened and no effective system to ensure that children who fail screenings access appropriate comprehensive eye examinations and follow-up care. RESULTS: The expansion of currently existing, or developing integrated health information systems, which would include child-level vision screening data, as well as referral records and follow-up diagnosis and treatment, is consistent with the proposed national approach to an integrated health information system (National Health Information Infrastructure). Development of an integrated vision data system will enhance eye health for young children at three different levels: (1) the child level, (2) the health care provider level, and (3) an epidemiological level. CONCLUSIONS: It is critical that the end users, the professionals who screen children and the professionals who provide eye care, be involved in the development and implementation of the proposed integrated data systems. As essential stakeholders invested in ensuring quality eye care for children, this community of professionals should find increasing need and opportunities at local, state, and national levels to contribute to cooperative guidance for data system development.


Asunto(s)
Prestación Integrada de Atención de Salud/normas , Necesidades y Demandas de Servicios de Salud/normas , Trastornos de la Visión/prevención & control , Selección Visual/normas , Niño , Preescolar , Prestación Integrada de Atención de Salud/organización & administración , Femenino , Personal de Salud , Humanos , Masculino , Derivación y Consulta , Estados Unidos
9.
Am J Transplant ; 14(10): 2235-45, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25135579

RESUMEN

With improved survival rates in solid organ transplantation there has been an increased focus on long-term outcomes following transplant, including physical function, health-related quality-of-life and cardiovascular mortality. Exercise training has the potential to affect these outcomes, however, research on the optimal timing, type, dose of exercise, mode of delivery and relevant outcomes is limited. This article provides a summary of a 2-day meeting held in April 2013 (Toronto, Canada) in which a multi-disciplinary group of clinicians, researchers, administrators and patient representatives engaged in knowledge exchange and discussion of key issues in exercise in solid organ transplant (SOT). The outcomes from the meeting were the development of top research priorities and a research agenda for exercise in SOT, which included the need for larger scale, multi-center intervention studies, development of standardized outcomes for physical function and surrogate measures for clinical trials, examining novel modes of exercise delivery and novel outcomes from exercise training studies such as immunity, infection, cognition and economic outcomes. The development and dissemination of "expert consensus guidelines," synthesizing both the best available evidence and expert opinion was prioritized as a key step toward improving program delivery.


Asunto(s)
Consenso , Ejercicio Físico , Trasplante de Órganos , Composición Corporal , Humanos , Calidad de Vida
10.
Acta Anaesthesiol Scand ; 58(8): 1032-9, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25060587

RESUMEN

BACKGROUND: During cardiopulmonary resuscitation (CPR) the ventilation/perfusion distribution (VA /Q) within the lung is difficult to assess. This experimental study examines the capability of multiple inert gas elimination (MIGET) to determine VA /Q under CPR conditions in a pig model. METHODS: Twenty-one anaesthetised pigs were randomised to three fractions of inspired oxygen (1.0, 0.7 or 0.21). VA/ Q by micropore membrane inlet mass spectrometry-derived MIGET was determined at baseline and during CPR following induction of ventricular fibrillation. Haemodynamics, blood gases, ventilation distribution by electrical impedance tomography and return of spontaneous circulation were assessed. Intergroup differences were analysed by non-parametric testing. RESULTS: MIGET measurements were feasible in all animals with an excellent correlation of measured and predicted arterial oxygen partial pressure (R(2) = 0.96, n = 21 for baseline; R(2) = 0.82, n = 21 for CPR). CPR induces a significant shift from normal VA /Q ratios to the high VA /Q range. Electrical impedance tomography indicates a dorsal to ventral shift of the ventilation distribution. Diverging pulmonary shunt fractions induced by the three inspired oxygen levels considerably increased during CPR and were traceable by MIGET, while 100% oxygen most negatively influenced the VA /Q. Return of spontaneous circulation were achieved in 52% of the animals. CONCLUSIONS: VA /Q assessment by MIGET is feasible during CPR and provides a novel tool for experimental purposes. Changes in VA /Q caused by different oxygen fractions are traceable during CPR. Beyond pulmonary perfusion deficits, these data imply an influence of the inspired oxygen level on VA /Q. Higher oxygen levels significantly increase shunt fractions and impair the normal VA /Q ratio.


Asunto(s)
Reanimación Cardiopulmonar , Espectrometría de Masas/métodos , Gases Nobles , Relación Ventilacion-Perfusión , Fibrilación Ventricular/terapia , Acetona/farmacocinética , Animales , Circulación Sanguínea , Estimulación Cardíaca Artificial , Desflurano , Impedancia Eléctrica , Enflurano/farmacocinética , Éter/farmacocinética , Estudios de Factibilidad , Hemodinámica , Isoflurano/análogos & derivados , Isoflurano/farmacocinética , Criptón/farmacocinética , Gases Nobles/farmacocinética , Oxígeno/sangre , Distribución Aleatoria , Hexafluoruro de Azufre/farmacocinética , Sus scrofa , Porcinos , Fibrilación Ventricular/sangre , Fibrilación Ventricular/fisiopatología
11.
JAMA Ophthalmol ; 142(6): 503-510, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38635258

RESUMEN

Importance: Parents may be concerned about the adverse outcomes of occlusion therapy in children treated for unilateral congenital cataract (UCC). Objective: To determine whether occlusion therapy in children treated for UCC with poor visual outcomes is negatively associated with poorer child and/or family functioning. Design, Setting, and Participants: This cohort study was conducted in 2023 using data collected between 2006 and 2016 in the Infant Aphakia Treatment Study (IATS). IATS participants with a visual acuity (VA) of 20/200 or worse were included. Statistical analysis was performed from July 2022 to October 2023. Exposure: Caregivers reported the mean daily minutes of patching during the 12 months prior to the VA assessment at 4.5 years of age. Patching was categorized as minimal (<15 minutes per day), moderate (15 to <120 minutes per day), or extensive (≥120 minutes per day). Main Outcome Measures: At 4.25 and 10.5 years of age, caregivers reported stress associated with the parenting role using the Parenting Stress Index and the Ocular Treatment Index and child behavior problems using the Achenbach Child Behavior Checklist. Motor skills were assessed at age 54 months using the Movement Assessment Battery for Children-Second Edition. Children completed the Harter Self-Perception Profile for Children at age 10.5 years. One-way analysis of variance and χ2 tests were used to compare outcomes by amount of patching. Results: Patching data were available for 47 of 53 children (88.7%) with a VA of 20/200 or worse. Among these 47 children with patching data included in the study, 20 (42.5%) were female, 27 (57.5%) were male, 12 (25.5%) were reported to have been patched fewer than 15 minutes per day, 11 (23.4%) were patched 16 to 119 minutes per day, and 24 (51.1%) were patched at least 120 minutes per day. Parenting stress, child behavior problems, motor functioning, and child self-perception were similar in all groups. For example, after adjusting for gender and insurance status, there was a nonsignificant difference between mean stress scores of 11.0 (95% CI, -4.5 to 26.5) points for parents who reported minimal patching vs parents who reported patching at least 120 minutes per day, and there was no significant difference in children's report of their global self-worth (0.0 [95% CI, -0.4 to 0.3] points). Conclusions and Relevance: Occlusion therapy was not negatively associated with family or child functioning. Although the sample size was limited, these results do not support changes to the current practice guidelines.


Asunto(s)
Catarata , Responsabilidad Parental , Estrés Psicológico , Agudeza Visual , Humanos , Catarata/congénito , Catarata/fisiopatología , Catarata/psicología , Masculino , Femenino , Agudeza Visual/fisiología , Preescolar , Niño , Responsabilidad Parental/psicología , Lactante , Afaquia Poscatarata/fisiopatología , Afaquia Poscatarata/terapia , Padres/psicología , Extracción de Catarata
12.
Br J Anaesth ; 110(2): 266-73, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23103776

RESUMEN

BACKGROUND: Cyclic recruitment and derecruitment (R/D) play a key role in the pathomechanism of acute lung injury (ALI) leading to respiration-dependent oscillations of arterial partial pressure of oxygen (Pa(O(2))). These Pa(O(2)) oscillations could also be forwarded to the cerebral microcirculation. METHODS: In 12 pigs, partial pressure of oxygen was measured in the thoracic aorta (Pa(O(2))) and subcortical cerebral tissue (Pbr(O(2))). Cerebral cortical haemoglobin oxygen saturation (Sbr(O(2))), cerebral blood flow (CBF), and peripheral haemoglobin saturation (Sp(O(2))) were assessed by spectroscopy and laser Doppler flowmetry. Measurements at different fractions of inspired oxygen (F(I(O(2)))) were performed at baseline and during cyclic R/D. STATISTICS: frequency domain analysis, the Mann-Whitney test, linear models to test the influence of Pa(O(2)) and systolic arterial pressure (SAP) oscillations on cerebral measurements. RESULTS: Parameters [mean (SD)] remained stable during baseline. Pa(O(2)) oscillations [10.6 (8) kPa, phase(reference)], systemic arterial pressure (SAP) oscillations [20 (9) mm Hg, phase(Pa(O(2))-SAP) -33 (72)°], and Sp(O(2))oscillations [1.9 (1.7)%, phase(Pa(O(2))-Sp(O(2))) 264 (72)°] were detected during lung R/D at 1.0. Pa(O(2)) oscillations decreased [2.7 (3.5) kPa, P=0.0008] and Sp(O(2)) oscillations increased [6.8 (3.9)%, P=0.0014] at F(I(O(2))) 0.3. In the brain, synchronized Pbr(O(2)) oscillations [0.6 (0.4) kPa, phase(Pa(O(2))-Pbr(O(2))) 90 (39)°], Sbr(O(2)) oscillations [4.1 (1.5)%, phase(Pa(O(2))-Sbr(O(2))) 182 (54)°], and CBF oscillations [198 (176) AU, phase(Pa(O(2))-CBF) 201 (63)°] occurred that were dependent on Pa(O(2)) and SAP oscillations. CONCLUSIONS: Pa(O(2)) oscillations caused by cyclic R/D are transmitted to the cerebral microcirculation in a porcine model of ALI. These cyclic oxygen alterations could play a role in the crosstalk of acute lung and brain injury.


Asunto(s)
Lesión Pulmonar Aguda/complicaciones , Lesión Pulmonar Aguda/fisiopatología , Circulación Cerebrovascular/fisiología , Pulmón/fisiopatología , Microcirculación/fisiología , Oxígeno/sangre , Anestesia General , Animales , Monitoreo de Gas Sanguíneo Transcutáneo , Presión Sanguínea/efectos de los fármacos , Líquido del Lavado Bronquioalveolar , Craneotomía , Hemodinámica/fisiología , Flujometría por Láser-Doppler , Respiración Artificial , Porcinos , Ventiladores Mecánicos
13.
Acta Anaesthesiol Scand ; 57(3): 320-5, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23167550

RESUMEN

BACKGROUND: Cyclic alveolar recruitment and derecruitment play a role in the pathomechanism of acute lung injury and may lead to arterial partial pressure of oxygen (PaO(2) ) oscillations within the respiratory cycle. It remains unknown, however, if these PaO(2) oscillations are transmitted to the microcirculation. The present study investigates if PaO(2) oscillations can be detected in the pig buccal mucosa microcirculation. METHODS: Respiratory failure was induced by surfactant depletion in seven pigs. PaO(2) oscillations caused by cyclic recruitment and derecruitment were measured in the thoracic aorta by fast fluorescence quenching of oxygen technology. Haemoglobin oxygen saturation, haemoglobin amount and blood flow in the buccal mucosa microcirculation were determined by combined fast white light spectrometry and laser Doppler flowmetry additionally to systolic arterial pressure. Measurements were performed during baseline conditions and during cyclic recruitment and derecruitment. RESULTS: Measurements remained stable during baseline. Respiratory-dependent oscillations occurred in the systemic circulation [PaO(2) oscillations 92 (69-172) mmHg; systolic arterial pressure oscillations 33 (13-35) %] and were related to the respiratory rate (5.0 ± 0.2/min) as confirmed by Fourier analysis. Synchronised oscillations were detected to the pig buccal mucosa microcirculation [haemoglobin oxygen saturation oscillations 3.4 (2.7-4.9) %; haemoglobin amount oscillations 8.5 (2.3-13.3) %; blood flow oscillations 66 (18-87) %]. The delay between PaO(2) -\ and microcirculatory oxygen oscillations was 7.2 ± 2.8 s. CONCLUSION: The present study suggests that PaO(2) oscillations caused by cyclic recruitment and derecruitment were transmitted to the buccal mucosa microcirculation. This non-invasive approach of measuring oxygen waves as a surrogate parameter of cyclic recruitment and derecruitment could be used to monitor PaO(2) oscillations at the bedside.


Asunto(s)
Mejilla/irrigación sanguínea , Oxígeno/sangre , Alveolos Pulmonares/fisiología , Animales , Aorta Torácica/fisiología , Presión Arterial , Lavado Broncoalveolar , Análisis de Fourier , Hemodinámica/fisiología , Flujometría por Láser-Doppler , Microcirculación/fisiología , Monitoreo Fisiológico , Intercambio Gaseoso Pulmonar , Flujo Sanguíneo Regional/fisiología , Insuficiencia Respiratoria/fisiopatología , Porcinos
14.
Acta Anaesthesiol Scand ; 57(3): 334-41, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23216436

RESUMEN

INTRODUCTION: The lectin-like domain of TNF-α enhances the fluid clearance across the alveolar barrier. For experimental purposes, the lectin-like domain can be mimicked by a synthetic peptide representing the TIP-motif of TNF-α. The present study aims to assess the acute effect of TIP on the pulmonary function in a porcine model of acute respiratory distress syndrome (ARDS). METHODS: Lung injury was induced in 16 pigs (25-27 kg) by bronchoalveolar lavage followed by injurious ventilation. Following randomisation, either nebulised TIP (1 mg/kg; AP301, APEPTICO, Vienna, Austria) or water for injection (control group) was administered. During 5 h of monitoring, the extravascular lung water index (EVLWI), the quotient of partial pressure of oxygen and inspired oxygen concentration (PaO(2) /FiO(2) ) and the pulmonary shunt fraction were repetitively assessed. The data were evaluated by an analysis of variance including Bonferroni-Holm correction. RESULTS: Comparable baseline conditions in both groups were achieved. Ventilatory parameters were standardised in both groups. In the TIP group, a significant reduction of the EVLWI and a simultaneous increase in the PaO(2) /FiO(2) ratio was shown (each P < 0.0001). No changes in the control group were observed (EVLWI: P = 0.43, PaO(2) /FiO(2) : P = 0.60). The intergroup comparison demonstrates a significant advantage of TIP inhalation over placebo (EVLWI: P < 0.0001, PaO(2) /FiO(2) : P = 0.004, shunt fraction: P = 0.0005). CONCLUSIONS: The inhalation of TIP induces an amelioration of clinical surrogate parameters of the lung function in a porcine lung injury model. By mimicking the lectin-like domain, the synthetic TIP peptide AP301 is an innovative approach as supportive therapy in ARDS.


Asunto(s)
Lesión Pulmonar/tratamiento farmacológico , Pulmón/efectos de los fármacos , Fragmentos de Péptidos/uso terapéutico , Factor de Necrosis Tumoral alfa/uso terapéutico , Animales , Lavado Broncoalveolar , Agua Pulmonar Extravascular/fisiología , Hemodinámica/fisiología , Lesión Pulmonar/fisiopatología , Oxígeno/sangre , Presión Parcial , Fragmentos de Péptidos/química , Respiración Artificial , Síndrome de Dificultad Respiratoria/tratamiento farmacológico , Síndrome de Dificultad Respiratoria/fisiopatología , Pruebas de Función Respiratoria , Porcinos , Factor de Necrosis Tumoral alfa/química
15.
Nat Genet ; 28(1): 73-6, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11326280

RESUMEN

Congenital disorders of glycosylation (CDG) comprise a rapidly growing group of inherited disorders in which glycosylation of glycoproteins is defective due to mutations in genes required for the assembly of lipid-linked oligosaccharides, their transfer to nascent glycoproteins (CDG-I) or the processing of protein-bound glycans (CDG-II). Previously' a defect in the GDP-fucose import into the lumen of the Golgi was identified in a person with CDG (A.C.) with a general deficiency of fucosyl residues in glycoproteins. This patient presents the clinical features of leukocyte adhesion deficiency type II (LAD II) including mental retardation, short stature, facial stigmata, and recurrent bacterial peripheral infections with persistently elevated peripheral leukocytes. Using a fucose-specific, lectin-staining procedure for detection of fucosylated glycoproteins and a retroviral cDNA library, we isolated a cDNA complementing the fucosylation defect in the patient's fibroblasts. The cDNA encodes a highly hydrophobic protein of 364 amino acids with multiple putative transmembrane domains. Restoration of GDP-fucose import activity in Golgi-enriched vesicles from the patient's fibroblasts verified the GDP-fucose transporter activity of this protein. We identified two missense mutations in the GDP-fucose transporter cDNA of patient A.C. and of two other people with LAD II. Thus complementation cloning allowed us to identify the human GDP-fucose transporter cDNA and GDP-fucose transporter deficiency as a cause for a new type of CDG. Following the recent recommendations for the nomenclature for CDG, this new type is classified as CDG-IIc (formerly LAD II).


Asunto(s)
Proteínas Portadoras/genética , Trastornos Congénitos de Glicosilación/genética , Guanosina Difosfato Fucosa/metabolismo , Proteínas de Transporte de Monosacáridos , Secuencia de Aminoácidos , Transporte Biológico , Células Cultivadas , Clonación Molecular , Trastornos Congénitos de Glicosilación/clasificación , Fibroblastos/citología , Prueba de Complementación Genética , Glicosilación , Humanos , Masculino , Datos de Secuencia Molecular , Homología de Secuencia de Aminoácido
16.
Am J Transplant ; 12(10): 2608-22, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22958872

RESUMEN

An increasing number of patients older than 65 years are referred for and have access to organ transplantation, and an increasing number of older adults are donating organs. Although short-term outcomes are similar in older versus younger transplant recipients, older donor or recipient age is associated with inferior long-term outcomes. However, age is often a proxy for other factors that might predict poor outcomes more strongly and better identify patients at risk for adverse events. Approaches to transplantation in older adults vary across programs, but despite recent gains in access and the increased use of marginal organs, older patients remain less likely than other groups to receive a transplant, and those who do are highly selected. Moreover, few studies have addressed geriatric issues in transplant patient selection or management, or the implications on health span and disability when patients age to late life with a transplanted organ. This paper summarizes a recent trans-disciplinary workshop held by ASP, in collaboration with NHLBI, NIA, NIAID, NIDDK and AGS, to address issues related to kidney, liver, lung, or heart transplantation in older adults and to propose a research agenda in these areas.


Asunto(s)
Trasplante de Órganos , Anciano , Asignación de Recursos para la Atención de Salud , Humanos , Inmunosupresores/uso terapéutico , Selección de Paciente , Justicia Social , Donantes de Tejidos , Resultado del Tratamiento
17.
Langmuir ; 28(13): 5795-801, 2012 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-22375701

RESUMEN

Viscoelastic braking theories developed by Shanahan and de Gennes and by others predict deformation of a solid surface at the solid-liquid-air contact line. This phenomenon has only been observed for soft smooth surfaces and results in a protrusion of the solid surface at the three-phase contact line, in agreement with the theoretical predictions. Despite the large (enough to break chemical bonds) forces associated with it, this deformation was not confirmed experimentally for hard surfaces, especially for hydrophobic ones. In this study we use superhydrophobic surfaces composed of an array of silicon nanostructures whose Young modulus is 4 orders of magnitude higher than that of surfaces in earlier recorded viscoelastic braking experiments. We distinguish between two cases: when a water drop forms an adhesive contact, albeit small, with the apparent contact angle θ < 180° and when the drop-surface adhesion is such that the conditions for placing a resting drop on the surface cannot be reached (i.e., θ = 180°). In the first case we show that there is a surface deformation at the three-phase contact line which is associated with a reduction in the hydrophobicity of the surface. For the second case, however, there cannot be a three-phase contact line associated with a drop in contact with the surface, and indeed, if we force-place a drop on the surface by holding it with a needle, no deformation is detected, nor is there a reduction in the hydrophobic properties of the surface. Yet, if we create a long horizontal three-phase contact line by partially immersing the superhydrophobic substrate in a water bath, we see a localized reduction in the hydrophobic properties of the surface in the region where the three-phase contact line used to be. The SEM scan of that region shows a narrow horizontal stripe where the nanorods are no longer there, and instead there is only a shallow structure that is lower than the nanorods height and resembles fused or removed nanorods. Away from that region, either on the part of the surface which was exposed to bulk water or the part which was exposed to air, no change in the hydrophobic properties of the surface is observed, and the SEM scan confirms that the nanorods seem intact in both regions.


Asunto(s)
Agua/química , Adhesivos/química , Elasticidad , Interacciones Hidrofóbicas e Hidrofílicas , Nanoestructuras/química , Silicio/química , Propiedades de Superficie , Viscosidad
18.
Anal Bioanal Chem ; 404(9): 2527-37, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22526652

RESUMEN

This critical review presents challenges and strategies in the detection of viral contaminants in food products. Adenovirus, caliciviruses, enteroviruses, and hepatitis A are emerging contaminant viruses. These viruses contaminate a variety of food products, including fruits, vegetables, shellfish, and ready-to-eat processed foods. The diversity of targets and sample matrices presents unique challenges to virus monitoring that have been addressed by a wide array of processing and detection methods. This review covers sample acquisition and handling, virus recovery/concentration, and the determination of targets using molecular biology and mass-spectrometric approaches. The concentration methods discussed include precipitation, antibody-based concentration, and filtration; the detection methods discussed include microscopy, polymerase chain reaction, nucleic acid sequence-based amplification, and mass spectrometry.


Asunto(s)
Análisis de los Alimentos/métodos , Contaminación de Alimentos/análisis , Alimentos/virología , Virus/aislamiento & purificación , Animales , Humanos , Espectrometría de Masas/métodos , Reacción en Cadena de la Polimerasa/métodos , Replicación de Secuencia Autosostenida/métodos , Virosis/virología
19.
N Engl J Med ; 359(22): 2313-23, 2008 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-19038878

RESUMEN

BACKGROUND: The addition of rituximab to combination chemotherapy with cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP), or R-CHOP, has significantly improved the survival of patients with diffuse large-B-cell lymphoma. Whether gene-expression signatures correlate with survival after treatment of diffuse large-B-cell lymphoma is unclear. METHODS: We profiled gene expression in pretreatment biopsy specimens from 181 patients with diffuse large-B-cell lymphoma who received CHOP and 233 patients with this disease who received R-CHOP. A multivariate gene-expression-based survival-predictor model derived from a training group was tested in a validation group. RESULTS: A multivariate model created from three gene-expression signatures--termed "germinal-center B-cell," "stromal-1," and "stromal-2"--predicted survival both in patients who received CHOP and patients who received R-CHOP. The prognostically favorable stromal-1 signature reflected extracellular-matrix deposition and histiocytic infiltration. By contrast, the prognostically unfavorable stromal-2 signature reflected tumor blood-vessel density. CONCLUSIONS: Survival after treatment of diffuse large-B-cell lymphoma is influenced by differences in immune cells, fibrosis, and angiogenesis in the tumor microenvironment.


Asunto(s)
Perfilación de la Expresión Génica , Expresión Génica , Linfoma de Células B Grandes Difuso/genética , Células del Estroma/metabolismo , Anticuerpos Monoclonales/administración & dosificación , Anticuerpos Monoclonales de Origen Murino , Protocolos de Quimioterapia Combinada Antineoplásica , Ciclofosfamida , Progresión de la Enfermedad , Doxorrubicina , Matriz Extracelular/genética , Regulación Neoplásica de la Expresión Génica , Genes MHC Clase II , Centro Germinal , Humanos , Factores Inmunológicos/administración & dosificación , Estimación de Kaplan-Meier , Linfoma de Células B Grandes Difuso/tratamiento farmacológico , Linfoma de Células B Grandes Difuso/mortalidad , Linfoma de Células B Grandes Difuso/patología , Persona de Mediana Edad , Análisis Multivariante , Neovascularización Patológica/genética , Prednisona , Pronóstico , Rituximab , Células del Estroma/patología , Vincristina
20.
Clin Transplant ; 25(5): E487-90, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21504475

RESUMEN

PURPOSE: The purpose of the study was to characterize differences in donor and recipient relationships between African American (AA) and Caucasian living kidney donors. METHODS: Data from all successful living kidney donors at a single institution between 1991 and 2009 were reviewed. Relationships between donor and recipient were categorized and between-group comparisons performed. RESULTS: The study sample consisted of 73 (18%) AA and 324 Caucasian living kidney donors. The distribution of donor-recipient relationships differed significantly between AA and Caucasians. AA donors were more likely to be related to the recipient (88% vs. 74%, p = 0.007) than Caucasians. AA donors were more likely to participate in child to parent donation and were less likely to participate in parent to child donation or to donate to unrelated individuals. Sibling and spousal donations were similar in both groups. Caucasian donors were more likely to be unrelated to the recipient than AA donors. CONCLUSIONS: Differences exist in donor-recipient relationships between AA and Caucasian living kidney donors. Future studies exploring cultural differences and family dynamics may provide targeted recruitment strategies for AA and Caucasian living kidney donors. Living unrelated kidney transplantation appears to be a potential growth area for living kidney donation in AA.


Asunto(s)
Negro o Afroamericano/estadística & datos numéricos , Trasplante de Riñón/psicología , Donadores Vivos/estadística & datos numéricos , Población Blanca/estadística & datos numéricos , Adulto , Actitud Frente a la Salud , Niño , Familia , Femenino , Humanos , Donadores Vivos/psicología , Masculino , Padres , Estudios Retrospectivos , Esposos
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