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1.
Child Psychiatry Hum Dev ; 52(5): 978-993, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-33067711

RESUMEN

Youth with a family history of substance use disorder (FH+) are more prone to have externalizing and internalizing problems compared to youth without a family history of substance use disorder (FH-), increasing the likelihood of later maladjustment. However, mechanisms for this association remain understudied. In this longitudinal study, we examined if FH+ youth are more likely to experience early-life stressors (ELS), which in turn would increase impulsivity and the expression of externalizing and internalizing behaviors. Data were collected from youth and a parent (n = 386) during a baseline assessment (age 10-12 years) and every six months when the youth was 13-16 years old. In support of the primary hypothesis, FH+ youth reported higher levels of externalizing and internalizing behaviors through ELS to impulsivity providing a developmental pathway through which FH+ youth are more prone to externalizing and internalizing problems.


Asunto(s)
Experiencias Adversas de la Infancia , Trastornos Relacionados con Sustancias , Adolescente , Niño , Humanos , Conducta Impulsiva , Estudios Longitudinales , Padres
2.
Knee Surg Sports Traumatol Arthrosc ; 18(11): 1456-64, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20127072

RESUMEN

Articular cartilage defects heal poorly. Autologous Matrix-Induced Chondrogenesis (AMIC) is an innovative treatment for localized full-thickness cartilage defects combining the well-known microfracturing with collagen scaffold and fibrin glue. The purpose of this prospective study was to evaluate the medium-term results of this enhanced microfracture technique for the treatment of chondral lesions of the knee. Thirty-two chondral lesions in 27 patients were treated with AMIC. Within the context of clinical follow-up, these patients were evaluated for up to 5 years after the intervention. Five different scores (Meyer score, Tegner score, Lysholm score, ICRS score, Cincinnati score) as well as radiographs were used for outcome analysis. Articular resurfacing was assessed by magnetic resonance imaging (MRI). The average age of patients (11 females, 16 males; mean body mass index 26, range 20-32) was 37 years (range 16-50 years). The mean defect size of the chondral lesions was 4.2 cm(2) (range 1.3-8.8 cm(2)). All defects were classified as grade IV according to the Outerbridge classification. The follow-up period was between 24 and 62 months with a mean of 37 months. Twenty out of 23 individuals (87%) questioned were subjectively highly satisfied with the results after surgery. Significant improvement (P < 0.05) of all scores was observed as early as 12 months after AMIC, and further increased values were notable up to 24 months postoperatively. MRI analysis showed moderate to complete filling with a normal to incidentally hyperintense signal in most cases. Results did not show a clinical impact of patient's age at the time of operation, body mass index and number of previous operations (n.s.). In contrast, males showed significant higher values in the ICRS score compared to their female counterparts. AMIC is an effective and safe method of treating symptomatic full-thickness chondral defects of the knee in appropriately selected cases. However, further studies with long-term follow-up are needed to determine whether the grafted area will maintain structural and functional integrity over time.


Asunto(s)
Cartílago Articular/cirugía , Condrogénesis/fisiología , Traumatismos de la Rodilla/cirugía , Andamios del Tejido , Adolescente , Adulto , Factores de Edad , Artroplastia Subcondral , Artroscopía , Cartílago Articular/lesiones , Condrocitos/trasplante , Femenino , Adhesivo de Tejido de Fibrina/farmacología , Estudios de Seguimiento , Humanos , Puntaje de Gravedad del Traumatismo , Traumatismos de la Rodilla/diagnóstico , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Medición de Riesgo , Factores Sexuales , Estadísticas no Paramétricas , Factores de Tiempo , Ingeniería de Tejidos/métodos , Trasplante Autólogo , Resultado del Tratamiento , Adulto Joven
3.
Biomech Model Mechanobiol ; 9(3): 295-315, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19943177

RESUMEN

Recent experimental and computational studies have shown that transmurally heterogeneous material properties through the arterial wall are critical to understanding the heterogeneous expressions of constituent degrading molecules. Given that expression of such molecules is thought to be intimately linked to local magnitudes of stress, modelling the transmural stress distribution is critical to understanding arterial adaption during disease. The aim of this study was to develop an arterial growth and remodelling framework that can incorporate both transmurally heterogeneous constituent distributions and residual stresses, into a 3-D finite element model. As an illustrative example, we model the development of a fusiform aneurysm and investigate the effects of elastinous and collagenous heterogeneities on the stress distribution during evolution. It is observed that the adaptive processes of growth and remodelling exhibit transmural variations. For physiological heterogeneous constituent distributions, a stress peak appears in the media towards the intima, and a stress plateau occurs towards the adventitia. These features can be primarily attributed to the underlying heterogeneity of elastinous constituents. During arterial adaption, the collagen strain is regulated to remain in its homoeostatic level; consequently, the partial stress of collagen has less influence on the total stress than the elastin. However, following significant elastin degradation, collagen plays the dominant role for the transmural stress profile and a marked stress peak occurs towards the adventitia. We conclude that to improve our understanding of the arterial adaption and the aetiology of arterial disease, there is a need to: quantify transmural constituent distributions during histopathological examinations, understand and model the role of the evolving transmural stress distribution.


Asunto(s)
Aneurisma/fisiopatología , Arterias/fisiopatología , Modelos Cardiovasculares , Adaptación Fisiológica , Animales , Simulación por Computador , Módulo de Elasticidad , Humanos , Resistencia al Corte
4.
J Perinatol ; 29(12): 814-21, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19626030

RESUMEN

OBJECTIVE: This study evaluated peripheral vasoconstriction in extremely low birth weight (ELBW) infants when body temperature decreased during the first 12 h of life. STUDY DESIGN: An exploratory, within-subjects design with 10 ELBW infants. Abdominal and foot temperatures were measured every minute. Peripheral vasoconstriction (abdominal>peripheral temperature by 2 degrees C) and abdominal-peripheral temperature difference were also evaluated. RESULTS: Abdominal and peripheral temperatures were significantly correlated within each infant. One 880 g infant exhibited isolated peripheral vasoconstriction; a 960-g infant had abdominal temperatures >1 degrees C higher than peripheral temperatures. Eight smaller infants exhibited no peripheral vasoconstriction and spent most of their observations with peripheral greater than abdominal temperatures. In eight infants, mean temperature difference was significantly higher when abdominal temperature was <36.5 degrees C. CONCLUSION: Most ELBW infants did not exhibit peripheral vasoconstriction during their first 12 h of life, despite low temperatures. ELBW infants' vasomotor control may be immature during this period.


Asunto(s)
Regulación de la Temperatura Corporal/fisiología , Recien Nacido con Peso al Nacer Extremadamente Bajo/fisiología , Recien Nacido Prematuro/fisiología , Vasoconstricción/fisiología , Femenino , Humanos , Hipotermia/fisiopatología , Recién Nacido , Masculino
5.
Int J Artif Organs ; 28(6): 638-47, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16015574

RESUMEN

The measurement of indicators such as saline diluted by blood flow provides important information on transport characteristics during extracorporeal blood treatments. When saline is injected and measured using the extracorporeal system, the effects caused by dispersion within the extracorporeal system have to be taken into consideration in order to adequately identify intracorporeal transport characteristics. It was the aim of this study to quantify the extracorporeal contribution and to obtain a transport function for specified sections of the extracorporeal system. The dispersion of saline following an impulsive input was measured in arterial and venous segments of customary extracorporeal blood lines with different distribution volumes (V = 23-87 mL) using a range of different blood flows (Qb = 200-450 ml/min). The dispersion was analyzed using a modified Gamma distribution function characterized by three parameters n, k, and tau, where n is real, positive, and n > or = 1, where k = Qb/Vt*n2, and where tau refers to the indicator appearance time at the sampling site. The parameters n, k, and tau were identified by fitting the model function to experimental data. The value of n was 2.3+/-0.5 and largely independent of the type of line segment, Qb, or Vt tau showed a strong dependence on Vt and Qb which was described by tau = Vt/Qb*(n-1)/n. Thus, with a given n, and when Vt and Qb are known, the transport function for saline in important sections of the extracorporeal circulation can be determined for specific experimental conditions. With this information indicator dilution curves measured in extracorporeal blood lines can be corrected for extracorporeal effects.


Asunto(s)
Circulación Extracorporea , Modelos Biológicos , Cloruro de Sodio/farmacocinética , Animales , Volumen Sanguíneo , Bovinos , Técnicas de Dilución del Indicador , Diálisis Renal
6.
Water Sci Technol ; 52(9): 43-51, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16445172

RESUMEN

The paper reports on the methodology and findings of a recent project on behalf of the Austrian Federal Ministry of Agriculture, Forestry, Environment and Water Management. The Ministry is seeking procedures for combining ecological and economic criteria to assess which technical urban water alternatives shall receive funding. To this end the current decision making process (DMP) for implementing urban water alternatives in Austria has been analyzed and compared with the situation elsewhere, e.g. in Sweden. The DMP entails specific requirements on assessment, whence the most common decision aid methodologies, ranging from LCA-based to multi-criteria methods, have been described and evaluated from an environmental, economic, legal and practical point of view, turning out recommendations to the Ministry. Their main points are: First the DMP should be kept as simple as possible in order to make it transparent. Second the aggregation of different criteria groups should and can be avoided. Therefore the stakeholders should not be allowed to make trade-offs. Finally clear objectives need to be stated.


Asunto(s)
Conservación de los Recursos Naturales , Eliminación de Residuos Líquidos , Abastecimiento de Agua , Austria , Ciudades , Conservación de los Recursos Naturales/economía , Conservación de los Recursos Naturales/métodos , Recolección de Datos , Toma de Decisiones , Política Pública , Eliminación de Residuos Líquidos/economía , Eliminación de Residuos Líquidos/métodos
7.
J Perinatol ; 20(1): 17-20, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-10693095

RESUMEN

OBJECTIVE: The purpose of this study was to determine the effects of prone and supine positioning on the cardiorespiratory stability of preterm infants with apnea and bradycardia. METHODS: A total of 22 preterm infants with symptomatic apnea and bradycardia (gestational age of 26.9 +/- 1.8 weeks and birth weight of 865 +/- 235 gm) were monitored for 24 hours (in four sequential 6-hour blocks) for apnea, bradycardia, and oxygen desaturation in alternating positions (prone or supine) following randomization. Postconceptional age at the time of study was 31.9 +/- 3.0 weeks. Respiratory rate, heart rate, and transcutaneous oxygen saturation were continuously monitored. All episodes of apnea (> or = 10 seconds), bradycardia (< 100 beats per minute), and oxygen desaturation (< 90%) were recorded on an event monitor. Episodes of apnea, bradycardia, and oxygen desaturation were defined as clinically significant if the following criteria were met: apnea, > or = 15 seconds; bradycardia, < 90 beats per minute; and oxygen desaturation, < 80%. All other recorded episodes were considered mild. The episodes were analyzed for statistical significance using the paired t-test. RESULTS: No significant differences (p > 0.05) in the incidence of clinically significant apnea, bradycardia, or desaturation between supine and prone positions were seen in these preterm infants. CONCLUSION: Our results suggest that the cardiorespiratory stability of preterm infants is not significantly compromised by supine positioning.


Asunto(s)
Apnea/etiología , Bradicardia/etiología , Recien Nacido Prematuro , Consumo de Oxígeno/fisiología , Posición Supina , Apnea/epidemiología , Bradicardia/epidemiología , Estudios Cruzados , Femenino , Humanos , Incidencia , Recién Nacido , Masculino , Probabilidad , Posición Prona , Sensibilidad y Especificidad , Muerte Súbita del Lactante/prevención & control
8.
J Virol ; 74(2): 892-8, 2000 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10623752

RESUMEN

Transcriptional transactivators (Tat) from human immunodeficiency and equine infectious anemia viruses (HIV and EIAV) interact with their transactivation response elements (TAR) to increase the rates of viral transcription. Whereas the human cyclin T1 is required for the binding of Tat to TAR from HIV, it is unknown how Tat from EIAV interacts with its TAR. Furthermore, Tat from EIAV functions in equine and canine cells but not in human cells. In this study, we present sequences of cyclins T1 from horse and dog and demonstrate that their N-terminal 300 residues rescue the transactivation of Tat from EIAV in human cells. Although human and equine cyclins T1 bind to this Tat, only the equine cyclin T1 supports the binding of Tat to TAR from EIAV. Finally, a reciprocal exchange of the valine for the leucine at position 29 in human and equine cyclins T1, respectively, renders the human cyclin T1 active and the equine cyclin T1 inactive for Tat transactivation from EIAV. Thus, the collaboration between a specific cyclin T1 and Tat for their high-affinity interaction with TAR is a common theme of lentiviral transactivation.


Asunto(s)
Ciclinas/metabolismo , Productos del Gen tat/metabolismo , Virus de la Anemia Infecciosa Equina/genética , Secuencias Repetidas Terminales , Secuencia de Aminoácidos , Sustitución de Aminoácidos , Animales , Secuencia de Bases , Ciclina T , Ciclinas/genética , Ciclinas/aislamiento & purificación , Perros , Productos del Gen tat/genética , Células HeLa , Caballos , Humanos , Virus de la Anemia Infecciosa Equina/metabolismo , Leucina/genética , Leucina/metabolismo , Datos de Secuencia Molecular , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/aislamiento & purificación , Proteínas Recombinantes de Fusión/metabolismo , Elementos de Respuesta , Homología de Secuencia de Aminoácido , Activación Transcripcional , Valina/genética , Valina/metabolismo
10.
Virology ; 255(1): 182-9, 1999 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-10049833

RESUMEN

The transcriptional transactivator (Tat) from the human immunodeficiency virus (HIV) does not function efficiently in Chinese hamster ovary (CHO) cells. Only somatic cell hybrids between CHO and human cells and CHO cells containing human chromosome 12 (CHO12) support high levels of Tat transactivation. This restriction was mapped to interactions between Tat and TAR. Recently, human cyclin T1 was found to increase the binding of Tat to TAR and levels of Tat transactivation in rodent cells. By combining individually with CDK9, cyclin T1 or related cyclins T2a and T2b form distinct positive transcription elongation factor b (P-TEFb) complexes. In this report, we found that of these three cyclins, only cyclin T1 is encoded on human chromosome 12 and is responsible for its effects in CHO cells. Moreover, only human cyclin T1, not mouse cyclin T1 or human cyclins T2a or T2b, supported interactions between Tat and TAR in vitro. Finally, after introducing appropriate receptors and human cyclin T1 into CHO cells, they became permissive for infection by and replication of HIV.


Asunto(s)
Ciclinas/metabolismo , Productos del Gen tat/metabolismo , Duplicado del Terminal Largo de VIH , VIH-1/fisiología , Replicación Viral , Animales , Antígenos CD4/genética , Antígenos CD4/metabolismo , Células CHO , Línea Celular Transformada , Cromosomas Humanos Par 12 , Cricetinae , Ciclina T , Ciclinas/genética , Regulación Viral de la Expresión Génica , Productos del Gen tat/genética , VIH-1/genética , Células HeLa , Humanos , Células Jurkat , Ratones , Provirus/genética , Receptores CCR5/genética , Receptores CCR5/metabolismo , Receptores CXCR4/genética , Receptores CXCR4/metabolismo , Receptores de Quimiocina , Activación Transcripcional , Productos del Gen tat del Virus de la Inmunodeficiencia Humana
11.
Proc Natl Acad Sci U S A ; 96(4): 1285-90, 1999 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-9990016

RESUMEN

The transcriptional transactivator Tat from HIV binds to the transactivation response element (TAR) RNA to increase rates of elongation of viral transcription. Human cyclin T supports these interactions between Tat and TAR. In this study, we report the sequence of mouse cyclin T and identify the residues from positions 1 to 281 in human cyclin T that bind to Tat and TAR. Mouse cyclin T binds to Tat weakly and is unable to facilitate interactions between Tat and TAR. Reciprocal exchanges of the cysteine and tyrosine at position 261 in human and mouse cyclin T proteins also render human cyclin T inactive and mouse cyclin T active. These findings reveal the molecular basis for the restriction of Tat transactivation in rodent cells.


Asunto(s)
Ciclinas/metabolismo , Cisteína , Productos del Gen tat/metabolismo , Duplicado del Terminal Largo de VIH/fisiología , Tirosina , Secuencia de Aminoácidos , Sustitución de Aminoácidos , Animales , Células CHO , Cloranfenicol O-Acetiltransferasa/metabolismo , Cricetinae , Ciclina T , Ciclinas/química , Ciclinas/genética , Humanos , Ratones , Datos de Secuencia Molecular , Mutagénesis Sitio-Dirigida , Proteínas Recombinantes de Fusión/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Alineación de Secuencia , Homología de Secuencia de Aminoácido
12.
J Virol ; 72(7): 5728-34, 1998 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9621031

RESUMEN

To evaluate the feasibility of using transgenic rabbits expressing CCR5 and CD4 as a small-animal model of human immunodeficiency virus type 1 (HIV) disease, we examined whether the expression of the human chemokine receptor (CCR5) and human CD4 would render a rabbit cell line (SIRC) permissive to HIV replication. Histologically, SIRC cells expressing CD4 and CCR5 formed multinucleated cells (syncytia) upon exposure to BaL, a macrophagetropic strain of HIV that uses CCR5 for cell entry. Intracellular viral capsid p24 staining showed abundant viral gene expression in BaL-infected SIRC cells expressing CD4 and CCR5. In contrast, neither SIRC cells expressing CD4 alone nor murine 3T3 cells expressing CCR5 and CD4 exhibited significant expression of p24. These stably transfected rabbit cells were also highly permissive for the production of virions upon infection by two other CCR5-dependent strains (JR-CSF and YU-2) but not by a CXCR4-dependent strain (NL4-3). The functional integrity of these virions was demonstrated by the successful infection of human peripheral blood mononuclear cells (PBMC) with viral stocks prepared from these transfected rabbit cells. Furthermore, primary rabbit PBMC were found to be permissive for production of infectious virions after circumventing the cellular entry step. These results suggest that a transgenic rabbit model for the study of HIV disease may be feasible.


Asunto(s)
Antígenos CD4/fisiología , VIH-1/fisiología , Receptores CCR5/fisiología , Animales , Electroporación , Productos del Gen nef/fisiología , Productos del Gen rev/fisiología , Productos del Gen tat/fisiología , Genes Virales , Células HeLa , Humanos , Ratones , Conejos , Replicación Viral , Productos del Gen nef del Virus de la Inmunodeficiencia Humana , Productos del Gen rev del Virus de la Inmunodeficiencia Humana , Productos del Gen tat del Virus de la Inmunodeficiencia Humana
14.
Implant Dent ; 6(3): 203-6, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9477784

RESUMEN

Although the Lew attachment was originally developed in 1977 to provide retention for overdentures fabricated in conjunction with subperiosteal implants, these attachments can be used with other types of implants. A case is presented describing the use of Lew attachments with a tapered bar and seven root form implants.


Asunto(s)
Diseño de Dentadura , Retención de Dentadura/instrumentación , Prótesis de Recubrimiento , Boca Edéntula/terapia , Técnica de Colado Dental , Implantación Dental Endoósea/métodos , Humanos , Masculino , Persona de Mediana Edad , Boca Edéntula/diagnóstico por imagen , Radiografía
15.
J Burn Care Rehabil ; 16(2 Pt 1): 136-40, 1995.
Artículo en Inglés | MEDLINE | ID: mdl-7775507

RESUMEN

The best donor site dressing would minimize pain while it increased the rate of healing. This study compares a standard fine-mesh gauze dressing, Xeroform (Sherwood Medical Industries Ltd., Markham, Ontario, Canada), to a new collagen-based dressing, SkinTemp (BioCore Inc., Topeka, Kan.). Eight patients requiring two donor sites of equal size received Xeroform gauze on one site and SkinTemp on the other. The Xeroform was covered for 24 hours and was then allowed to air-dry. Healing was determined to be complete once the gauze peeled off and complete epithelialization was observed. The SkinTemp was covered for 7 days and inspected on days 3, 5, and 7. Pain was measured daily with a standard visual analog scale. Mean Xeroform donor site size was 224.75 cm2, and SkinTemp size was 319.87 cm2. Donor site thickness was 0.012 to 0.014 inches for both. Mean length of healing was 10.62 days for Xeroform and 7.75 days for SkinTemp. Mean pain rating was 22.28 mm for Xeroform and 15.29 mm for SkinTemp. The overall preference of the eight subjects yielded five choosing SkinTemp and three choosing Xeroform, and seven reported SkinTemp as less painful. SkinTemp dressing appears to be less painful and has a better healing rate compared with Xeroform.


Asunto(s)
Vendajes , Quemaduras/cirugía , Trasplante de Piel , Cicatrización de Heridas , Adolescente , Adulto , Colágeno , Femenino , Humanos , Masculino , Persona de Mediana Edad
17.
Child Welfare ; 69(6): 563-9, 1990.
Artículo en Inglés | MEDLINE | ID: mdl-1703474

RESUMEN

United Methodist Family Services of Virginia placed 41 developmentally disabled children in adoptive homes between August 1985 and June 1988, representing a range of chronic emotional, intellectual, and physical disabilities. This article describes the need for specialized adoption programs for children with developmental disabilities and the methods used in placing these children. The obstacles to adoption of children with developmental disabilities are also discussed.


Asunto(s)
Adopción , Discapacidades del Desarrollo/rehabilitación , Servicio Social/economía , Publicidad , Niño , Financiación Gubernamental , Necesidades y Demandas de Servicios de Salud , Humanos , Servicio Social/organización & administración , Virginia
18.
Drugs ; 34 Suppl 1: 71-3, 1987.
Artículo en Inglés | MEDLINE | ID: mdl-3481331

RESUMEN

The efficacy and tolerance of ofloxacin and doxycycline were compared in patients with lower respiratory tract infections. Doses used were 200 or 400mg twice daily for ofloxacin and 100mg twice daily for doxycycline. Of 230 patients treated, 219 could be assessed for effectiveness. 88 patients were treated for exacerbations of chronic bronchitis and 131 for pneumonia. Clinical cure was achieved in 18 of 52 patients with bronchitis treated with ofloxacin. Improvement occurred in 29 and failure in 5. In the doxycycline-treated bronchitis group 11 of 36 patients were cured, 22 improved and 1 failure occurred. Of 62 patients with pneumonia who were administered ofloxacin, 34 were cured, 26 improved and treatment failed in 2. In the doxycycline-treated group of patients with pneumonia 39 of 69 were cured, 23 improved and 7 failed to respond. Two patients experienced adverse effects during ofloxacin treatment and 7 while receiving doxycycline.


Asunto(s)
Antiinfecciosos/uso terapéutico , Doxiciclina/uso terapéutico , Oxazinas/uso terapéutico , Infecciones del Sistema Respiratorio/tratamiento farmacológico , Antiinfecciosos/efectos adversos , Bronquitis/tratamiento farmacológico , Bronquitis/microbiología , Enfermedad Crónica , Humanos , Pruebas de Sensibilidad Microbiana , Ofloxacino , Oxazinas/efectos adversos , Neumonía/tratamiento farmacológico , Neumonía/microbiología , Distribución Aleatoria , Infecciones del Sistema Respiratorio/microbiología
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