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1.
Environ Sci Technol ; 57(28): 10151-10172, 2023 07 18.
Artículo en Inglés | MEDLINE | ID: mdl-37364241

RESUMEN

Passive sampling devices (PSDs) are increasingly used at contaminated sites to improve the characterization of contaminant transport and assessment of ecological and human health risk at sediment sites and to evaluate the effectiveness of remedial actions. The use of PSDs after full-scale remediation remains limited, however, in favor of evaluation based on conventional metrics, such as bulk sediment concentrations or bioaccumulation. This review has three overall aims: (1) identify sites where PSDs have been used to support cleanup efforts, (2) assess how PSD-derived remedial end points compare to conventional metrics, and (3) perform broad semiquantitative and selective quantitative concurrence analyses to evaluate the magnitude of agreement between metrics. Contaminated sediment remedies evaluated included capping, in situ amendment, dredging and monitored natural recovery (MNR). We identify and discuss 102 sites globally where PSDs were used to determine remedial efficacy resulting in over 130 peer-reviewed scientific publications and numerous technical reports and conference proceedings. The most common conventional metrics assessed alongside PSDs in the peer-reviewed literature were bioaccumulation (39%), bulk sediments (40%), toxicity (14%), porewater grab samples (16%), and water column grab samples (16%), while about 25% of studies used PSDs as the sole metric. In a semiquantitative concurrence analysis, the PSD-based metrics agreed with conventional metrics in about 68% of remedy assessments. A more quantitative analysis of reductions in bioaccumulation after remediation (i.e., remediation was successful) showed that decreases in uptake into PSDs agreed with decreases in bioaccumulation (within a factor of 2) 61% of the time. Given the relatively good agreement between conventional and PSD-based metrics, we propose several practices and areas for further study to enhance the utilization of PSDs throughout the remediation of contaminated sediment sites.


Asunto(s)
Restauración y Remediación Ambiental , Contaminantes Químicos del Agua , Humanos , Benchmarking , Sedimentos Geológicos/análisis , Contaminantes Químicos del Agua/toxicidad , Monitoreo del Ambiente
2.
High Educ (Dordr) ; 85(3): 503-520, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-35431321

RESUMEN

Flipped classrooms have become widely adopted in educational settings (e.g., in higher education) worldwide. However, there is a need for more precise understanding of the ingredients for student satisfaction in a flipped setting. The aim of this paper was to investigate university students' experiences of the factors that create a successful flipped course. Ten measures were used to investigate the hypothesized factors affecting satisfaction, which were chosen based on the results from previous flipped classroom studies and higher educational research. These measures were grouped into three dimensions: (1) pedagogical (five measures), (2) social (three measures), and (3) technological (two measures). Exploratory factor analysis was run to analyze the adequacy of the instruments. Results revealed that the factor structure was as expected and that the instruments measuring all ten factors of teaching and learning in a flipped classroom were adequate. Furthermore, confirmatory factor analysis was used to formally operationalize the hypothesized latent constructs, and to build a structural equation model for predicting the student satisfaction of a flipped classroom. In the end, seven factors were found to predict student satisfaction with flipped courses. The highest predictor was guidance from the dimension of pedagogy, and the second-best predictor was experienced teaching for understanding. The results, limitations, and conclusion are discussed in terms of key issues and the development of a flipped classroom pedagogical design for higher education.

3.
Blood ; 135(8): 547-557, 2020 02 20.
Artículo en Inglés | MEDLINE | ID: mdl-31899794

RESUMEN

Erythroferrone (ERFE) is produced by erythroblasts in response to erythropoietin (EPO) and acts in the liver to prevent hepcidin stimulation by BMP6. Hepcidin suppression allows for the mobilization of iron to the bone marrow for the production of red blood cells. Aberrantly high circulating ERFE in conditions of stress erythropoiesis, such as in patients with ß-thalassemia, promotes the tissue iron accumulation that substantially contributes to morbidity in these patients. Here we developed antibodies against ERFE to prevent hepcidin suppression and to correct the iron loading phenotype in a mouse model of ß-thalassemia [Hbb(th3/+) mice] and used these antibodies as tools to further characterize ERFE's mechanism of action. We show that ERFE binds to BMP6 with nanomolar affinity and binds BMP2 and BMP4 with somewhat weaker affinities. We found that BMP6 binds the N-terminal domain of ERFE, and a polypeptide derived from the N terminus of ERFE was sufficient to cause hepcidin suppression in Huh7 hepatoma cells and in wild-type mice. Anti-ERFE antibodies targeting the N-terminal domain prevented hepcidin suppression in ERFE-treated Huh7 cells and in EPO-treated mice. Finally, we observed a decrease in splenomegaly and serum and liver iron in anti-ERFE-treated Hbb(th3/+) mice, accompanied by an increase in red blood cells and hemoglobin and a decrease in reticulocyte counts. In summary, we show that ERFE binds BMP6 directly and with high affinity, and that antibodies targeting the N-terminal domain of ERFE that prevent ERFE-BMP6 interactions constitute a potential therapeutic tool for iron loading anemias.


Asunto(s)
Anticuerpos Neutralizantes/uso terapéutico , Citocinas/antagonistas & inhibidores , Hepcidinas/metabolismo , Proteínas Musculares/antagonistas & inhibidores , Talasemia/tratamiento farmacológico , Animales , Anticuerpos Neutralizantes/farmacología , Línea Celular , Citocinas/química , Citocinas/metabolismo , Células HEK293 , Humanos , Hierro/metabolismo , Masculino , Ratones Endogámicos C57BL , Proteínas Musculares/química , Proteínas Musculares/metabolismo , Dominios Proteicos/efectos de los fármacos , Talasemia/metabolismo
4.
Blood ; 132(14): 1473-1477, 2018 10 04.
Artículo en Inglés | MEDLINE | ID: mdl-30097509

RESUMEN

Decreased hepcidin mobilizes iron, which facilitates erythropoiesis, but excess iron is pathogenic in ß-thalassemia. Erythropoietin (EPO) enhances erythroferrone (ERFE) synthesis by erythroblasts, and ERFE suppresses hepatic hepcidin production through an unknown mechanism. The BMP/SMAD pathway in the liver is critical for hepcidin control, and we show that EPO suppressed hepcidin and other BMP target genes in vivo in a partially ERFE-dependent manner. Furthermore, recombinant ERFE suppressed the hepatic BMP/SMAD pathway independently of changes in serum and liver iron. In vitro, ERFE decreased SMAD1, SMAD5, and SMAD8 phosphorylation and inhibited expression of BMP target genes. ERFE specifically abrogated the induction of hepcidin by BMP5, BMP6, and BMP7 but had little or no effect on hepcidin induction by BMP2, BMP4, BMP9, or activin B. A neutralizing anti-ERFE antibody prevented ERFE from inhibiting hepcidin induction by BMP5, BMP6, and BMP7. Cell-free homogeneous time-resolved fluorescence assays showed that BMP5, BMP6, and BMP7 competed with anti-ERFE for binding to ERFE. We conclude that ERFE suppresses hepcidin by inhibiting hepatic BMP/SMAD signaling via preferentially impairing an evolutionarily closely related BMP subgroup of BMP5, BMP6, and BMP7. ERFE can act as a natural ligand trap generated by stimulated erythropoiesis to regulate the availability of iron.


Asunto(s)
Proteína Morfogenética Ósea 6/metabolismo , Citocinas/metabolismo , Hepcidinas/metabolismo , Proteínas Musculares/metabolismo , Animales , Línea Celular , Células Hep G2 , Humanos , Hierro/metabolismo , Hígado/metabolismo , Masculino , Ratones , Transducción de Señal , Proteínas Smad/metabolismo
5.
Genome Res ; 25(5): 624-32, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25792610

RESUMEN

Gene duplication and alternative splicing are important sources of proteomic diversity. Despite research indicating that gene duplication and alternative splicing are negatively correlated, the evolutionary relationship between the two remains unclear. One manner in which alternative splicing and gene duplication may be related is through the process of subfunctionalization, in which an alternatively spliced gene upon duplication divides distinct splice isoforms among the newly generated daughter genes, in this way reducing the number of alternatively spliced transcripts duplicate genes produce. Previously, it has been shown that splice form subfunctionalization will result in duplicate pairs with divergent exon structure when distinct isoforms become fixed in each paralog. However, the effects of exon structure divergence between paralogs have never before been studied on a genome-wide scale. Here, using genomic data from human, mouse, and zebrafish, we demonstrate that gene duplication followed by exon structure divergence between paralogs results in a significant reduction in levels of alternative splicing. In addition, by comparing the exon structure of zebrafish duplicates to the co-orthologous human gene, we have demonstrated that a considerable fraction of exon divergent duplicates maintain the structural signature of splice form subfunctionalization. Furthermore, we find that paralogs with divergent exon structure demonstrate reduced breadth of expression in a variety of tissues when compared to paralogs with identical exon structures and singletons. Taken together, our results are consistent with subfunctionalization partitioning alternatively spliced isoforms among duplicate genes and as such highlight the relationship between gene duplication and alternative splicing.


Asunto(s)
Empalme Alternativo , Genoma , Animales , Evolución Molecular , Exones , Duplicación de Gen , Humanos , Ratones , Pez Cebra
6.
Radiology ; 287(3): 795-804, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29714681

RESUMEN

Purpose To quantify the burden and distribution of asymptomatic atherosclerosis in a population with a low to intermediate risk of cardiovascular disease. Materials and Methods Between June 2008 and February 2013, 1528 participants with 10-year risk of cardiovascular disease less than 20% were prospectively enrolled. They underwent whole-body magnetic resonance (MR) angiography at 3.0 T by using a two-injection, four-station acquisition technique. Thirty-one arterial segments were scored according to maximum stenosis. Scores were summed and normalized for the number of assessable arterial segments to provide a standardized atheroma score (SAS). Multiple linear regression was performed to assess effects of risk factors on atheroma burden. Results A total of 1513 participants (577 [37.9%] men; median age, 53.5 years; range, 40-83 years) completed the study protocol. Among 46 903 potentially analyzable segments, 46 601 (99.4%) were interpretable. Among these, 2468 segments (5%) demonstrated stenoses, of which 1649 (3.5%) showed stenosis less than 50% and 484 (1.0%) showed stenosis greater than or equal to 50%. Vascular stenoses were distributed throughout the body with no localized distribution. Seven hundred forty-seven (49.4%) participants had at least one stenotic vessel, and 408 (27.0%) participants had multiple stenotic vessels. At multivariable linear regression, SAS correlated with age (B = 3.4; 95% confidence interval: 2.61, 4.20), heart rate (B = 1.23; 95% confidence interval: 0.51, 1.95), systolic blood pressure (B = 0.02; 95% confidence interval: 0.01, 0.03), smoking status (B = 0.79; 95% confidence interval: 0.44, 1.15), and socioeconomic status (B = -0.06; 95% confidence interval: -0.10, -0.02) (P < .01 for all). Conclusion Whole-body MR angiography identifies early vascular disease at a population level. Although disease prevalence is low on a per-vessel level, vascular disease is common on a per-participant level, even in this low- to intermediate-risk cohort. © RSNA, 2018 Online supplemental material is available for this article.


Asunto(s)
Aterosclerosis/diagnóstico por imagen , Aterosclerosis/epidemiología , Angiografía por Resonancia Magnética/métodos , Imagen de Cuerpo Entero/métodos , Adulto , Anciano , Anciano de 80 o más Años , Medios de Contraste , Femenino , Humanos , Aumento de la Imagen/métodos , Masculino , Persona de Mediana Edad , Prevalencia , Estudios Prospectivos , Riesgo , Escocia/epidemiología
7.
J Cardiovasc Magn Reson ; 20(1): 7, 2018 01 30.
Artículo en Inglés | MEDLINE | ID: mdl-29382349

RESUMEN

BACKGROUND: Arteriosclerosis (arterial stiffening) is associated with future cardiovascular events, with this effect postulated to be due to its effect on cardiac afterload, atherosclerosis (plaque formation) progression or both, but with limited evidence examining these early in disease formation. The aim of the current study is to examine the association between arteriosclerosis, atherosclerosis and ventricular remodelling in a population at low-intermediate cardiovascular risk. METHODS: One thousand six hundred fifty-one subjects free of clinical cardiovascular disease and with a < 20% 10 year cardiovascular risk score underwent a cardiovascular magnetic resonance (CMR) study and whole body CMR angiogram. Arteriosclerosis was measured using total arterial compliance (TAC) - calculated as the indexed stroke volume divided by the pulse pressure. Atherosclerosis was quantified using a standardised atheroma score (SAS) which was calculated by scoring 30 arterial segments within the body based on the degree of stenosis, summating these scores and normalising it to the number of assessable segments. Left ventricular remodelling was measured using left ventricular mass to volume ratio (LVMVR). RESULTS: One thousand five hundred fifteen (38% male, 53.8 ± 8.2 years old) completed the study. On univariate analysis TAC was associated with SAS but this was lost after accounting for cardiovascular risk factors in both males (B = - 0.001 (- 0.004-0.002),p = 0.62) and females (B = 0.000(95%CI -0.002--0.002),p = 0.78). In contrast compliance correlated with LVMVR after accounting for cardiovascular risk factors (B = - 0.12(95%CI -0.16--0.091),p < 0.001 in males; B = - 0.12(95%CI -0.15--0.086),p < 0.001 in females). CONCLUSION: Systemic arteriosclerosis is associated with left ventricular remodelling but not atherosclerosis. Future efforts in cardiovascular risk prevention should thus seek to address both arteriosclerosis and atherosclerosis individually.


Asunto(s)
Arteriosclerosis/diagnóstico por imagen , Cardiopatías/diagnóstico por imagen , Angiografía por Resonancia Magnética , Imagen por Resonancia Cinemagnética , Enfermedad Arterial Periférica/diagnóstico por imagen , Rigidez Vascular , Función Ventricular Izquierda , Remodelación Ventricular , Arteriosclerosis/fisiopatología , Estudios de Casos y Controles , Femenino , Cardiopatías/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Enfermedad Arterial Periférica/fisiopatología , Placa Aterosclerótica , Valor Predictivo de las Pruebas , Pronóstico , Imagen de Cuerpo Entero
8.
Proc Natl Acad Sci U S A ; 112(50): 15354-9, 2015 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-26621728

RESUMEN

Although humanized antibodies have been highly successful in the clinic, all current humanization techniques have potential limitations, such as: reliance on rodent hosts, immunogenicity due to high non-germ-line amino acid content, v-domain destabilization, expression and formulation issues. This study presents a technology that generates stable, soluble, ultrahumanized antibodies via single-step complementarity-determining region (CDR) germ-lining. For three antibodies from three separate key immune host species, binary substitution CDR cassettes were inserted into preferred human frameworks to form libraries in which only the parental or human germ-line destination residue was encoded at each position. The CDR-H3 in each case was also augmented with 1 ± 1 random substitution per clone. Each library was then screened for clones with restored antigen binding capacity. Lead ultrahumanized clones demonstrated high stability, with affinity and specificity equivalent to, or better than, the parental IgG. Critically, this was mainly achieved on germ-line frameworks by simultaneously subtracting up to 19 redundant non-germ-line residues in the CDRs. This process significantly lowered non-germ-line sequence content, minimized immunogenicity risk in the final molecules and provided a heat map for the essential non-germ-line CDR residue content of each antibody. The ABS technology therefore fully optimizes the clinical potential of antibodies from rodents and alternative immune hosts, rendering them indistinguishable from fully human in a simple, single-pass process.


Asunto(s)
Anticuerpos Monoclonales/inmunología , Anticuerpos Monoclonales/uso terapéutico , Regiones Determinantes de Complementariedad/inmunología , Células Germinativas/inmunología , Secuencia de Aminoácidos , Animales , Anticuerpos Monoclonales/química , Especificidad de Anticuerpos/inmunología , Células Clonales , Regiones Determinantes de Complementariedad/química , Simulación por Computador , Ensayo de Inmunoadsorción Enzimática , Epítopos de Linfocito T/inmunología , Humanos , Inmunoglobulina G/química , Inmunoglobulina G/inmunología , Cadenas Pesadas de Inmunoglobulina/química , Cadenas Pesadas de Inmunoglobulina/inmunología , Cadenas Ligeras de Inmunoglobulina/química , Cadenas Ligeras de Inmunoglobulina/inmunología , Región Variable de Inmunoglobulina/química , Región Variable de Inmunoglobulina/inmunología , Modelos Moleculares , Datos de Secuencia Molecular , Mutación/genética , Biblioteca de Péptidos , Estabilidad Proteica , Estructura Terciaria de Proteína , Ratas , Alineación de Secuencia , Análisis de Secuencia de Proteína , Proteínas tau/química , Proteínas tau/inmunología
9.
J Magn Reson Imaging ; 44(5): 1186-1196, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27143317

RESUMEN

PURPOSE: To scan a volunteer population using 3.0T magnetic resonance imaging (MRI). MRI of the left ventricular (LV) structure and function in healthy volunteers has been reported extensively at 1.5T. MATERIALS AND METHODS: A population of 1528 volunteers was scanned. A standardized approach was taken to acquire steady-state free precession (SSFP) LV data in the short-axis plane, and images were quantified using commercial software. Six observers undertook the segmentation analysis. RESULTS: Mean values (±standard deviation, SD) were: ejection fraction (EF) = 69 ± 6%, end diastolic volume index (EDVI) = 71 ± 13 ml/m2 , end systolic volume index (ESVI) = 22 ± 7 ml/m2 , stroke volume index (SVI) = 49 ± 8 ml/m2 , and LV mass index (LVMI) = 55 ± 12 g/m2 . The mean EF was slightly larger for females (69%) than for males (68%), but all other variables were smaller for females (EDVI 68v77 ml/m2 , ESVI 21v25 ml/m2 , SVI 46v52 ml/m2 , LVMI 49v64 g/m2 , all P < 0.05). The mean LV volume data mostly decreased with each age decade (EDVI males: -2.9 ± 1.3 ml/m2 , females: -3.1 ± 0.8 ml/m2 ; ESVI males: -1.3 ± 0.7 ml/m2 , females: -1.7 ± 0.5 ml/m2 ; SVI males: -1.7 ± 0.9 ml/m2 , females: -1.4 ± 0.6 ml/m2 ; LVMI males: -1.6 ± 1.1 g/m2 , females: -0.2 ± 0.6 g/m2 ) but the mean EF was virtually stable in males (0.6 ± 0.6%) and rose slightly in females (1.2 ± 0.5%) with age. CONCLUSION: LV reference ranges are provided in this population-based MR study at 3.0T. The variables are similar to those described at 1.5T, including variations with age and gender. These data may help to support future population-based MR research studies that involve the use of 3.0T MRI scanners. J. Magn. Reson. Imaging 2016;44:1186-1196.


Asunto(s)
Envejecimiento/patología , Envejecimiento/fisiología , Ventrículos Cardíacos/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Volumen Sistólico/fisiología , Función Ventricular Izquierda/fisiología , Adulto , Distribución por Edad , Anciano , Anciano de 80 o más Años , Femenino , Ventrículos Cardíacos/anatomía & histología , Humanos , Imagen por Resonancia Magnética/estadística & datos numéricos , Masculino , Tamizaje Masivo , Persona de Mediana Edad , Valores de Referencia , Distribución por Sexo , Factores Sexuales , Reino Unido/epidemiología
10.
Augment Altern Commun ; 32(3): 208-18, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27184193

RESUMEN

This study compared longitudinal changes in mastery motivation during parent-child free play for 37 children with complex communication needs. Mastery motivation manifests as a willingness to work hard at tasks that are challenging, which is an important quality to overcoming the challenges involved in successful expressive communication using AAC. Unprompted parent-child play episodes were identified in three assessment sessions over an 18-month period and coded for nine categories of mastery motivation in social and object play. All of the object-oriented mastery motivation categories and one social mastery motivation category showed an influence of motor skills after controlling for receptive language. Object play elicited significantly more of all of the object-focused mastery motivation categories than social play, and social play elicited more of one type of social-focused mastery motivation behavior than object play. Mastery motivation variables did not differ significantly over time for children. Potential physical and interpersonal influences on mastery motivation for parents and children with complex communication needs are discussed, including broadening the procedures and definitions of mastery motivation beyond object-oriented measurements for children with complex communication needs.


Asunto(s)
Trastornos de la Comunicación/psicología , Motivación , Lesiones Encefálicas/complicaciones , Lesiones Encefálicas/psicología , Parálisis Cerebral/complicaciones , Parálisis Cerebral/psicología , Preescolar , Equipos de Comunicación para Personas con Discapacidad , Trastornos de la Comunicación/etiología , Trastornos de la Comunicación/rehabilitación , Discapacidades del Desarrollo/complicaciones , Discapacidades del Desarrollo/psicología , Femenino , Humanos , Lactante , Estudios Longitudinales , Masculino , Disrafia Espinal/complicaciones , Disrafia Espinal/psicología
11.
J Emot Behav Disord ; 23(4): 206-214, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26604659

RESUMEN

Youth in residential care have significant mental health needs which require regular progress monitoring; however, very few emotional or behavioral assessments have been examined with this unique, high-risk population. This study examined the psychometrics of the Symptom Functioning and Severity Scale, a brief 24-item measure designed to assess the emotional and behavioral status of youth. This study examined the SFSS ratings from 143 youth with a disruptive behavior diagnosis living in a group-home facility in the Midwest and 52 of their service providers. Overall, the findings suggest that the psychometrics of the SFSS, when rated by staff or youth were similar to the original outpatient clinical samples. More specifically, the Rasch analyses indicate that the SFSS items and the overall scale is performing adequately, and the confirmatory factor analyses replicated the two-factor structure for staff. However, the fit of the two-factor model was less compelling for youth ratings. In all, the brief SFSS seems a promising measure for assessing problem severity for youth in residential care.

12.
J Emot Behav Disord ; 23(2): 90-100, 2015 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-25960629

RESUMEN

OBJECTIVE: To examine the link between therapeutic alliance and youth outcomes. METHOD: The study was conducted at a group-home with 112 youth with a disruptive-behavior diagnosis. Therapeutic alliance was collected routinely via youth and staff report. Outcome data were collected using youth and staff reports of externalizing behavior as well as behavioral incidents occurring during care. Outcome data were collected following intake into services and at 6 and 12 months of care. Data were analyzed to examine (1) if youth behavior problems at intake were predictive of therapeutic alliance and (2) if changes in alliance were predictive of subsequent youth outcomes. These were conducted with a 6-month service-delivery model and replicated with a 12-month model. RESULTS: There was some support for the first hypothesis, that initial levels of youth externalizing behavior would be related to alliance ratings; however, most of the effects were marginally significant. The second hypothesis, that changes in therapeutic alliance would be related to subsequent youth outcomes, was supported for the 6-month model, but not the 12-month model. CONCLUSIONS: Changes in therapeutic alliance may be predictive of youth outcomes during care. Additional research into examining therapeutic alliance trajectories is warranted to improve mental health services for youth.

13.
Infant Ment Health J ; 36(3): 287-97, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25916271

RESUMEN

In a previous study with a nationally representative sample, researchers found that the items of the Preschool Behavioral and Emotional Rating Scale can best be described by a four-factor structure model (Emotional Regulation, School Readiness, Social Confidence, and Family Involvement). The findings of this investigation replicate and extend these previous results with a national sample of children (N = 1,075) with disabilities enrolled in early childhood special education programs. Data were analyzed using classical tests theory, Rasch modeling, and confirmatory factor analysis. Results confirmed that for the most part, individual items were internally consistent within a four-factor model and showed consistent item difficulty, discrimination, and fit relative to their respective subscale scores.


Asunto(s)
Conducta Infantil , Emociones , Pruebas Psicológicas , Conducta Infantil/psicología , Preescolar , Educación Especial , Femenino , Humanos , Masculino , Psicometría , Estados Unidos
14.
Adm Policy Ment Health ; 42(3): 356-62, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25037614

RESUMEN

Tests that measure the emotional and behavioral problems of children and youth are typically not normed and standardized on youth diagnosed with disruptive behavior, particularly those youth in residential care. Yet professional standards mandate that before instruments are used with a specific population the psychometric properties need to be studied and re-established: specifically, psychometric properties, including validity, need to be evaluated (AERA, APA, and NCME, The standards for educational and psychological testing. AERA, Washington, DC, 1999). The purpose of the present study was to assess the validity characteristics of the Symptoms and Functioning Severity Scale (SFSS; Bickman et al., Manual of the Peabody Treatment Progress Battery, Vanderbilt University, Nashville, TN, 2010), a widely used test developed for use in outpatient clinics, with youth in a residential care program. The convergent validity of the SFSS was established with the large correlations (0.78-0.86) with the CBCL. Several binary classification analyses including specificity, area under the receiver operating characteristic curve, positive and negative likelihood ratios, and the Youden Index supported the validity of the SFSS. However, the sensitivity index was somewhat low indicating the test may produce a high level of false negatives. Limitations, future research and implications are discussed.


Asunto(s)
Déficit de la Atención y Trastornos de Conducta Disruptiva/diagnóstico , Hogares para Grupos , Problema de Conducta , Tratamiento Domiciliario , Adolescente , Atención Ambulatoria , Instituciones de Atención Ambulatoria , Área Bajo la Curva , Niño , Femenino , Humanos , Funciones de Verosimilitud , Masculino , Psicometría , Curva ROC , Instituciones Residenciales , Índice de Severidad de la Enfermedad , Encuestas y Cuestionarios
15.
J Immunol ; 188(1): 322-33, 2012 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-22131336

RESUMEN

Examination of 1269 unique naive chicken V(H) sequences showed that the majority of positions in the framework (FW) regions were maintained as germline, with high mutation rates observed in the CDRs. Many FW mutations could be clearly related to the modulation of CDR structure or the V(H)-V(L) interface. CDRs 1 and 2 of the V(H) exhibited frequent mutation in solvent-exposed positions, but conservation of common structural residues also found in human CDRs at the same positions. In comparison with humans and mice, the chicken CDR3 repertoire was skewed toward longer sequences, was dominated by small amino acids (G/S/A/C/T), and had higher cysteine (chicken, 9.4%; human, 1.6%; and mouse, 0.25%) but lower tyrosine content (chicken, 9.2%; human, 16.8%; and mouse 26.4%). A strong correlation (R(2) = 0.97) was observed between increasing CDR3 length and higher cysteine content. This suggests that noncanonical disulfides are strongly favored in chickens, potentially increasing CDR stability and complexity in the topology of the combining site. The probable formation of disulfide bonds between CDR3 and CDR1, FW2, or CDR2 was also observed, as described in camelids. All features of the naive repertoire were fully replicated in the target-selected, phage-displayed repertoire. The isolation of a chicken Fab with four noncanonical cysteines in the V(H) that exhibits 64 nM (K(D)) binding affinity for its target proved these constituents to be part of the humoral response, not artifacts. This study supports the hypothesis that disulfide bond-constrained CDR3s are a structural diversification strategy in the restricted germline v-gene repertoire of chickens.


Asunto(s)
Sustitución de Aminoácidos , Pollos/genética , Regiones Determinantes de Complementariedad/genética , Cadenas Pesadas de Inmunoglobulina/genética , Mutación , Animales , Afinidad de Anticuerpos/genética , Camelus/genética , Camelus/inmunología , Pollos/inmunología , Regiones Determinantes de Complementariedad/inmunología , Disulfuros/inmunología , Humanos , Cadenas Pesadas de Inmunoglobulina/inmunología , Ratones , Estabilidad Proteica , Especificidad de la Especie
16.
Lancet Microbe ; 5(4): e335-e344, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38484748

RESUMEN

BACKGROUND: The origin of novel SARS-CoV-2 spike sequences found in wastewater, without corresponding detection in clinical specimens, remains unclear. We sought to determine the origin of one such cryptic wastewater lineage by tracking and characterising its persistence and genomic evolution over time. METHODS: We first detected a cryptic lineage, WI-CL-001, in municipal wastewater in Wisconsin, USA, in January, 2022. To determine the source of WI-CL-001, we systematically sampled wastewater from targeted sub-sewershed lines and maintenance holes using compositing autosamplers. Viral concentrations in wastewater samples over time were measured by RT digital PCR. In addition to using metagenomic 12s rRNA sequencing to determine the virus's host species, we also sequenced SARS-CoV-2 spike receptor binding domains, and, where possible, whole viral genomes to identify and characterise the evolution of this lineage. FINDINGS: We traced WI-CL-001 to its source at a single commercial building. There we detected the cryptic lineage at concentrations as high as 2·7 × 109 genome copies per L. The majority of 12s rRNA sequences detected in wastewater leaving the identified source building were human. Additionally, we generated over 100 viral receptor binding domain and whole-genome sequences from wastewater samples containing the cryptic lineage collected over the 13 consecutive months this virus was detectable (January, 2022, to January, 2023). These sequences contained a combination of fixed nucleotide substitutions characteristic of Pango lineage B.1.234, which circulated in humans in Wisconsin at low levels from October, 2020, to February, 2021. Despite this, mutations in the spike gene and elsewhere resembled those subsequently found in omicron variants. INTERPRETATION: We propose that prolonged detection of WI-CL-001 in wastewater indicates persistent shedding of SARS-CoV-2 from a single human initially infected by an ancestral B.1.234 virus. The accumulation of convergent omicron-like mutations in WI-CL-001's ancestral B.1.234 genome probably reflects persistent infection and extensive within-host evolution. People who shed cryptic lineages could be an important source of highly divergent viruses that sporadically emerge and spread. FUNDING: The Rockefeller Foundation, Wisconsin Department of Health Services, Centers for Disease Control and Prevention, National Institute on Drug Abuse, and the Center for Research on Influenza Pathogenesis and Transmission.


Asunto(s)
COVID-19 , Aguas Residuales , Estados Unidos , Humanos , SARS-CoV-2/genética , COVID-19/epidemiología , Centers for Disease Control and Prevention, U.S.
17.
BMC Bioinformatics ; 14: 325, 2013 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-24237905

RESUMEN

BACKGROUND: The common ancestor of salmonid fishes, including rainbow trout (Oncorhynchus mykiss), experienced a whole genome duplication between 20 and 100 million years ago, and many of the duplicated genes have been retained in the trout genome. This retention complicates efforts to detect allelic variation in salmonid fishes. Specifically, single nucleotide polymorphism (SNP) detection is problematic because nucleotide variation can be found between the duplicate copies (paralogs) of a gene as well as between alleles. RESULTS: We present a method of differentiating between allelic and paralogous (gene copy) sequence variants, allowing identification of SNPs in organisms with multiple copies of a gene or set of genes. The basic strategy is to: 1) identify windows of unique cDNA sequences with homology to each other, 2) compare these unique cDNAs if they are not shared between individuals (i.e. the cDNA is homozygous in one individual and homozygous for another cDNA in the other individual), and 3) give a "SNP score" value between zero and one to each candidate sequence variant based on six criteria. Using this strategy we were able to detect about seven thousand potential SNPs from the transcriptomes of several clonal lines of rainbow trout. When directly compared to a pre-validated set of SNPs in polyploid wheat, we were also able to estimate the false-positive rate of this strategy as 0 to 28% depending on parameters used. CONCLUSIONS: This strategy has an advantage over traditional techniques of SNP identification because another dimension of sequencing information is utilized. This method is especially well suited for identifying SNPs in polyploids, both outbred and inbred, but would tend to be conservative for diploid organisms.


Asunto(s)
Duplicación de Gen , Polimorfismo de Nucleótido Simple , Transcriptoma , Animales , Secuencia de Bases , Genoma , Genómica , Humanos , Datos de Secuencia Molecular , Oncorhynchus mykiss/genética , Poliploidía , Alineación de Secuencia
18.
J Biol Chem ; 287(53): 44425-34, 2012 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-23148212

RESUMEN

Highly specific antibodies to phosphoepitopes are valuable tools to study phosphorylation in disease states, but their discovery is largely empirical, and the molecular mechanisms mediating phosphospecific binding are poorly understood. Here, we report the generation and characterization of extremely specific recombinant chicken antibodies to three phosphoepitopes on the Alzheimer disease-associated protein tau. Each antibody shows full specificity for a single phosphopeptide. The chimeric IgG pT231/pS235_1 exhibits a K(D) of 0.35 nm in 1:1 binding to its cognate phosphopeptide. This IgG is murine ortholog-cross-reactive, specifically recognizing the pathological form of tau in brain samples from Alzheimer patients and a mouse model of tauopathy. To better understand the underlying binding mechanisms allowing such remarkable specificity, we determined the structure of pT231/pS235_1 Fab in complex with its cognate phosphopeptide at 1.9 Å resolution. The Fab fragment exhibits novel complementarity determining region (CDR) structures with a "bowl-like" conformation in CDR-H2 that tightly and specifically interacts with the phospho-Thr-231 phosphate group, as well as a long, disulfide-constrained CDR-H3 that mediates peptide recognition. This binding mechanism differs distinctly from either peptide- or hapten-specific antibodies described to date. Surface plasmon resonance analyses showed that pT231/pS235_1 binds a truly compound epitope, as neither phosphorylated Ser-235 nor free peptide shows any measurable binding affinity.


Asunto(s)
Enfermedad de Alzheimer/metabolismo , Anticuerpos/inmunología , Epítopos/inmunología , Proteínas tau/inmunología , Enfermedad de Alzheimer/genética , Secuencia de Aminoácidos , Animales , Anticuerpos/química , Anticuerpos/genética , Encéfalo/metabolismo , Pollos , Epítopos/química , Epítopos/genética , Humanos , Inmunoglobulina G/química , Inmunoglobulina G/genética , Inmunoglobulina G/inmunología , Ratones , Ratones Transgénicos , Datos de Secuencia Molecular , Fosforilación , Proteínas tau/química , Proteínas tau/genética , Proteínas tau/metabolismo
19.
Qual Life Res ; 22(8): 2151-7, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23196923

RESUMEN

PURPOSE: The Pediatric Quality of Life assessment (PedsQL™) is the most widely used measure for assessing adolescent health-related quality of life (HRQoL). While youth in residential treatment facilities face many physical and mental health, behavioral, education, and familial challenges that could impact their HRQoL, no research has sought to assess the factor structure of the PedsQL™ among youth receiving residential care. METHODS: High school-aged youth (N = 229) attending a large residential treatment center in Omaha, NE were recruited to complete a data collection packet comprised of various health assessments including the PedsQL. Four competing confirmatory factor analysis models were used to test the hypothesized internal structure of the PedsQL™ 4.0 Teen Report. RESULTS: Models A, B, and C had acceptable CFI (≥.90), TLI (≥.90), and RMSEA (≤.08) fit indicators. However, factor loadings for items 5 and 6 were problematic. After removing the two problematic items, Model D was fit to the data and proved to be the superior of the four models. This model included two first-order factors (physical health problems; school attendance problems) and one second-order factor (psychological health problems). CONCLUSIONS: The findings suggest that researchers and practitioners studying youth in residential settings can reliably use the PedsQL™ to assess their HRQoL.


Asunto(s)
Estado de Salud , Pediatría/normas , Psicometría/estadística & datos numéricos , Calidad de Vida/psicología , Tratamiento Domiciliario , Encuestas y Cuestionarios/normas , Adolescente , Niño , Recolección de Datos , Análisis Factorial , Femenino , Humanos , Masculino , Salud Mental , Psicometría/métodos , Reproducibilidad de los Resultados
20.
Child Youth Serv Rev ; 35(1): 56-64, 2013 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-23264715

RESUMEN

Therapeutic alliance has been frequently studied in individual counseling sessions; however, research on therapeutic alliance in residential settings for youth with mental health diagnoses has been limited. This may be due, in part, to the presence of multiple service providers often in caregiving roles. The purpose of this study was to examine the psychometric quality of a widely utilized measure of therapeutic alliance used in psychotherapy with youth in residential care where the treatment is provided by a trained married couple. We also compared the relationship between youth ratings of their male and female service provider, as well as examined correlations in ratings between youth and staff on therapeutic alliance. Finally, we investigated the direction, magnitude, and trajectory of change in therapeutic alliance over a 12-month period following admission into residential care. The method was a longitudinal assessment of 135 youth and 124 staff regarding therapeutic alliance over the course of 12 months or discharge from services. Results indicated strong psychometric properties and high correlations for youth ratings of both their male and female service providers. However, the correlation was low between youth and service provider ratings of alliance. Longitudinal analyses indicated that rates of therapeutic alliance changed over time.

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