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1.
Nat Commun ; 12(1): 7126, 2021 12 08.
Artículo en Inglés | MEDLINE | ID: mdl-34880204

RESUMEN

DNA double-strand breaks are a major threat to cellular survival and genetic integrity. In addition to high fidelity repair, three intrinsically mutagenic DNA break repair routes have been described, i.e. single-strand annealing (SSA), polymerase theta-mediated end-joining (TMEJ) and residual ill-defined microhomology-mediated end-joining (MMEJ) activity. Here, we identify C. elegans Helicase Q (HELQ-1) as being essential for MMEJ as well as for SSA. We also find HELQ-1 to be crucial for the synthesis-dependent strand annealing (SDSA) mode of homologous recombination (HR). Loss of HELQ-1 leads to increased genome instability: patchwork insertions arise at deletion junctions due to abortive rounds of polymerase theta activity, and tandem duplications spontaneously accumulate in genomes of helq-1 mutant animals as a result of TMEJ of abrogated HR intermediates. Our work thus implicates HELQ activity for all DSB repair modes guided by complementary base pairs and provides mechanistic insight into mutational signatures common in HR-defective cancers.


Asunto(s)
Proteínas de Caenorhabditis elegans , Roturas del ADN de Doble Cadena , ADN Helicasas , Reparación del ADN , Animales , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/genética , ADN , Reparación del ADN por Unión de Extremidades , ADN Helicasas/genética , Inestabilidad Genómica , Recombinación Homóloga , Mutación
2.
Nat Commun ; 12(1): 6217, 2021 11 02.
Artículo en Inglés | MEDLINE | ID: mdl-34728617

RESUMEN

Natural sounds, and bird song in particular, play a key role in building and maintaining our connection with nature, but widespread declines in bird populations mean that the acoustic properties of natural soundscapes may be changing. Using data-driven reconstructions of soundscapes in lieu of historical recordings, here we quantify changes in soundscape characteristics at more than 200,000 sites across North America and Europe. We integrate citizen science bird monitoring data with recordings of individual species to reveal a pervasive loss of acoustic diversity and intensity of soundscapes across both continents over the past 25 years, driven by changes in species richness and abundance. These results suggest that one of the fundamental pathways through which humans engage with nature is in chronic decline, with potentially widespread implications for human health and well-being.


Asunto(s)
Acústica , Aves/fisiología , Vocalización Animal/fisiología , Animales , Biodiversidad , Aves/clasificación , Conservación de los Recursos Naturales , Europa (Continente) , Humanos , América del Norte , Dinámica Poblacional , Estaciones del Año , Sonido , Vocalización Animal/clasificación
3.
Pneumologie ; 75(1): 33-38, 2021 Jan.
Artículo en Alemán | MEDLINE | ID: mdl-32707588

RESUMEN

A 62-year-old patient with bronchial asthma and chronic rhinosinusitis underwent inguinal hernia surgery. After the operation, sudden circulatory arrest occurred, requiring cardiopulmonary resuscitation. Coronary angiography revealed a 99 % proximal stenosis of right coronary artery (RCA) with unsuspicious and smooth coronary vessel walls. In the further course, several similar events occurred, but without pathological findings in the coronary angiography. Initially, echocardiography showed slightly reduced left ventricular ejection fraction of 45 %. Chest radiography revealed bilateral pulmonary infiltrates, and white blood cell count showed severe eosinophilia (37 %). Serological antibody testing including ANA, ENA and c-/p-ANCA was negative. Myeloproliferative pathologies were excluded by bone marrow puncture. The patient suffered from emerging dyspnea, weakness, and ongoing weight loss. A methylprednisolone pulse of 250 mg/d for 3 days remained without significant effect, so that the patient was eventually referred to our university hospital due to ongoing clinical deterioration. On admission, the patient suffered from weakness, progressive muscular atrophy, and dyspnea on exertion. Physical examination revealed a right-sided peroneal paralysis. Bronchial lavage detected severe eosinophil alveolitis (37 %), and laboratory findings showed elevated cardiac enzymes and NT-proBNP (Troponin-T > 700 ng/l, NT-proBNP > 10.000 ng/l). Echocardiography revealed a dramatic deterioration of cardiac function (LVEF 16 %). Interdisciplinary discussion between pulmonologists and cardiologists lead to the diagnosis of ANCA-negative eosinophilic granulomatosis with polyangiitis (EGPA) with pulmonary and cardiac involvement. Initiation of immunosuppressive therapy with methylprednisolone 1000 mg/d for 3 days followed by cyclophosphamide therapy (6 pulses, administered every 4 weeks) led to substantial symptomatic improvement, complete regression of pulmonary infiltrates and marked recovery of cardiac function (LVEF 47 %). CONCLUSION: Serological detection of elevated ANCAs is not necessary for diagnosis of EGPA. Only 30 - 70 % of patients are positive for these, particularly if neurological and/or renal rather than cardiac and/or pulmonary involvement is present. This may be a pitfall in establishing the correct diagnosis. Induction therapy with cyclophosphamide is the preferred treatment for steroid-refractory EGPA with life-threatening organ involvement.


Asunto(s)
Síndrome de Churg-Strauss/complicaciones , Eosinofilia/complicaciones , Granulomatosis con Poliangitis/complicaciones , Cardiopatías/complicaciones , Hipertrofia Ventricular Izquierda/tratamiento farmacológico , Función Ventricular Izquierda/efectos de los fármacos , Anticuerpos Anticitoplasma de Neutrófilos/uso terapéutico , Síndrome de Churg-Strauss/tratamiento farmacológico , Angiografía Coronaria , Estenosis Coronaria , Ciclofosfamida/uso terapéutico , Disnea/etiología , Ecocardiografía , Eosinofilia/patología , Granulomatosis con Poliangitis/tratamiento farmacológico , Granulomatosis con Poliangitis/inmunología , Humanos , Hipertrofia Ventricular Izquierda/diagnóstico por imagen , Hipertrofia Ventricular Izquierda/etiología , Hipertrofia Ventricular Izquierda/fisiopatología , Factores Inmunológicos/uso terapéutico , Inmunosupresores/uso terapéutico , Imagen por Resonancia Magnética , Persona de Mediana Edad , Volumen Sistólico
4.
Microb Ecol ; 81(4): 1029-1041, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33170351

RESUMEN

Nitrogen removal is an important process for wastewater ponds prior to effluent release. Bacteria and archaea can drive nitrogen removal if they possess the genes required to metabolize nitrogen. In the tropical savanna of northern Australia, we identified the previously unresolved microbial communities responsible for nitrogen cycling in a multi-pond wastewater stabilization system by measuring genomic DNA and cDNA for the following: nifH (nitrogen fixation); nosZ (denitrification); hzsA (anammox); archaeal AamoA and bacterial BamoA (ammonia oxidation); nxrB (nitrite oxidation); and nrfA (dissimilatory NO3 reduction to NH3). By collecting 160 DNA and 40 cDNA wastewater samples and measuring nitrogen (N)-cycling genes using a functional gene array, we found that genes from all steps of the N cycle were present and, except for nxrB, were also expressed. As expected, N-cycling communities showed daily, seasonal, and yearly shifts. However, contrary to our prediction, probes from most functional groups, excluding nosZ and AamoA, were different between ponds. Further, different genes that perform the same N-cycling role sometimes had different trends over space and time, resulting in only weak correlations between the different functional communities. Although N-cycling communities were correlated with wastewater nitrogen levels and physico-chemistry, the relationship was not strong enough to reliably predict the presence or diversity of N-cycling microbes. The complex and dynamic response of these genes to other functional groups and the changing physico-chemical environment provides insight into why altering wastewater pond conditions can result an abundance of some gene variants while others are lost.


Asunto(s)
Nitrógeno , Estanques , Archaea/genética , Desnitrificación , Genes Microbianos , Nitrógeno/análisis , Ciclo del Nitrógeno , Oxidación-Reducción , Aguas Residuales
5.
Behav Brain Res ; 395: 112837, 2020 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-32739286

RESUMEN

INTRODUCTION: Changes in visual attention have been argued to influence freezing of gait (FOG) in people with Parkinson's Disease (PD). However, the specific visual search patterns of people with FOG pathology (PD + FOG) and potential underlying mechanisms are not well understood. The current study explored visual search behavior in PD + FOG while walking on a pathway featuring environmental features known to exacerbate FOG (e.g., narrow doorway and tripping hazards). Potential underpinning attentional mechanisms were also assessed, such as conscious movement processing. METHODS: Visual search behavior of twelve people with PD + FOG tested in ON-state (Mage = 74.3) and twelve age-matched healthy controls (Mage = 72.5) were analyzed during a complex walking task. The task required participants to step over an obstacle and navigate through a narrow doorway, surrounded by clutter. RESULTS: People with PD + FOG more frequently directed visual attention to ongoing and imminent steps compared to healthy controls (Mdn = 26% vs Mdn = 14%, respectively; p = 0.042). Self-reported conscious movement processing was also significantly higher in people with PD + FOG. The one participant who froze during the walking task fixated the future trip hazard (obstacle, approximately 6 steps ahead) almost exclusively during freezing trials (i.e., 60-100% of the trial). In contrast, during 'non-freeze' trials, this participant increased the duration of fixations towards ongoing and imminent steps. CONCLUSION: Results suggest that people with PD + FOG strongly monitor/control ongoing and immediately upcoming stepping movements. However, prolonged fixations towards threats to future movements might prevent people with PD + FOG from processing the visual information needed to do this, thereby provoke freezing episodes.


Asunto(s)
Marcha/fisiología , Enfermedad de Parkinson/fisiopatología , Desempeño Psicomotor/fisiología , Anciano , Anciano de 80 o más Años , Femenino , Análisis de la Marcha/métodos , Humanos , Masculino , Persona de Mediana Edad , Movimiento , Caminata/fisiología
6.
Nat Commun ; 11(1): 3615, 2020 07 17.
Artículo en Inglés | MEDLINE | ID: mdl-32680986

RESUMEN

Failure to preserve the integrity of the genome is a hallmark of cancer. Recent studies have revealed that loss of the capacity to repair DNA breaks via homologous recombination (HR) results in a mutational profile termed BRCAness. The enzymatic activity that repairs HR substrates in BRCA-deficient conditions to produce this profile is currently unknown. We here show that the mutational landscape of BRCA1 deficiency in C. elegans closely resembles that of BRCA1-deficient tumours. We identify polymerase theta-mediated end-joining (TMEJ) to be responsible: knocking out polq-1 suppresses the accumulation of deletions and tandem duplications in brc-1 and brd-1 animals. We find no additional back-up repair in HR and TMEJ compromised animals; non-homologous end-joining does not affect BRCAness. The notion that TMEJ acts as an alternative to HR, promoting the genome alteration of HR-deficient cells, supports the idea that polymerase theta is a promising therapeutic target for HR-deficient tumours.


Asunto(s)
Proteínas de Caenorhabditis elegans/genética , Caenorhabditis elegans/genética , Reparación del ADN por Unión de Extremidades , ADN Polimerasa Dirigida por ADN/metabolismo , Proteínas Supresoras de Tumor/genética , Ubiquitina-Proteína Ligasas/genética , Animales , Animales Modificados Genéticamente , Análisis Mutacional de ADN , ADN Polimerasa Dirigida por ADN/genética , Técnicas de Inactivación de Genes , Mutación , ADN Polimerasa theta
7.
Eur J Pediatr ; 178(8): 1195-1205, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31152317

RESUMEN

This study aims to evaluate the etiology of pediatric sensorineural hearing loss (SNHL). A total of 423 children with SNHL were evaluated, with the focus on the determination of causative genetic and acquired etiologies of uni- and bilateral SNHL in relation to age at diagnosis and severity of the hearing loss. We found that a stepwise diagnostic approach comprising of imaging, genetic, and/or pediatric evaluation identified a cause for SNHL in 67% of the children. The most common causative finding in children with bilateral SNHL was causative gene variants (26%), and in children with unilateral SNHL, a structural anomaly of the temporal bone (27%). The probability of finding an etiologic diagnosis is significantly higher in children under the age of 1 year and children with profound SNHL.Conclusions: With our stepwise diagnostic approach, we found a diagnostic yield of 67%. Bilateral SNHL often has a genetic cause, whereas in unilateral SNHL structural abnormalities of the labyrinth are the dominant etiologic factor. The diagnostic yield is associated with the age at detection and severity of hearing loss: the highest proportion of causative abnormalities is found in children with a young age at detection or a profound hearing loss. What is Known: • Congenital sensorineural hearing loss is one of the most common congenital disorders • Determination of the cause is important for adequate management and prognosis and may include radiology, serology, and DNA analysis What is New: • Using a stepwise diagnostic approach, causative abnormalities are found in 67% both in uni- and bilateral SNHL, with the highest diagnostic yield in very young children and those suffering from profound hearing loss • Bilateral SNHL often has a genetic cause, whereas in unilateral SNHL structural abnormalities of the labyrinth are the dominant etiologic factor.


Asunto(s)
Pérdida Auditiva Sensorineural/diagnóstico , Pérdida Auditiva Sensorineural/etiología , Adolescente , Audiometría , Niño , Preescolar , Femenino , Marcadores Genéticos , Pruebas Genéticas , Pérdida Auditiva Bilateral/diagnóstico , Pérdida Auditiva Bilateral/etiología , Pérdida Auditiva Unilateral/diagnóstico , Pérdida Auditiva Unilateral/etiología , Humanos , Lactante , Recién Nacido , Imagen por Resonancia Magnética , Masculino , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Tomografía Computarizada por Rayos X
8.
Clin Genet ; 94(2): 221-231, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29676012

RESUMEN

This study focuses on further characterization of the audiovestibular phenotype and on genotype-phenotype correlations of DFNB77, an autosomal recessive type of hearing impairment (HI). DFNB77 is associated with disease-causing variants in LOXHD1, and is genetically and phenotypically highly heterogeneous. Heterozygous deleterious missense variants in LOXHD1 have been associated with late-onset Fuchs corneal dystrophy (FCD). However, up to now screening for FCD of heterozygous carriers in DFNB77 families has not been reported. This study describes the genotype and audiovestibular phenotype of 9 families with DFNB77. In addition, carriers within the families were screened for FCD. Fifteen pathogenic missense and truncating variants were identified, of which 12 were novel. The hearing phenotype showed high inter- and intrafamilial variation in severity and progression. There was no evidence for involvement of the vestibular system. None of the carriers showed (pre-clinical) symptoms of FCD. Our findings expand the genotypic and phenotypic spectrum of DFNB77, but a clear correlation between the type or location of the variant and the severity or progression of HI could not be established. We hypothesize that environmental factors or genetic modifiers are responsible for phenotypic differences. No association was found between heterozygous LOXHD1 variants and the occurrence of FCD in carriers.


Asunto(s)
Proteínas Portadoras/genética , Distrofia Endotelial de Fuchs/genética , Predisposición Genética a la Enfermedad , Pérdida Auditiva Sensorineural/genética , Adolescente , Adulto , Audiometría , Niño , Preescolar , Femenino , Distrofia Endotelial de Fuchs/fisiopatología , Estudios de Asociación Genética , Genotipo , Pérdida Auditiva Sensorineural/fisiopatología , Heterocigoto , Humanos , Masculino , Persona de Mediana Edad , Mutación Missense , Linaje , Fenotipo
9.
Int J Pediatr Otorhinolaryngol ; 108: 180-185, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29605351

RESUMEN

OBJECTIVE: To evaluate the clinically relevant abnormalities as visualized on CT and MR imaging in children with symmetric and asymmetric bilateral sensorineural hearing loss (SNHL), in relation to age and the severity of hearing loss. STUDY DESIGN: Retrospective cohort study. SETTING: Tertiary referral otology and audiology center. PATIENTS AND DIAGNOSTIC INTERVENTIONS: From January 2006 until January 2016, a total of 207 children diagnosed with symmetric and asymmetric bilateral SNHL were included. They underwent CT and/or MR imaging for the evaluation of the etiology of their hearing loss. MAIN OUTCOME MEASURES: Radiologic abnormalities associated with SNHL. RESULTS: 302 scans were performed in 207 children (median age of 0.8 years old) with bilateral SNHL. The most frequently identified cause of bilateral SNHL was a malformation of the labyrinth. The combined diagnostic yield of CT and MR imaging was 32%. The diagnostic yield of MR (34%) was considerably higher than that of CT (20%). We found a higher rate of abnormalities in children with profound hearing loss (41%) compared to milder hearing loss (8-29%), and in asymmetric SNHL (52%) compared to symmetric SNHL (30%). CONCLUSION: Imaging is essential in the etiologic evaluation of children with bilateral SNHL. The highest diagnostic yield is found in children with bilateral asymmetric SNHL or profound SNHL. Based on our findings, MR is the primary imaging modality of choice in the etiological evaluation of children with bilateral SNHL because of its high diagnostic yield.


Asunto(s)
Pérdida Auditiva Bilateral/diagnóstico por imagen , Pérdida Auditiva Sensorineural/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Tomografía Computarizada por Rayos X/métodos , Adolescente , Niño , Preescolar , Estudios de Cohortes , Oído Interno/anomalías , Femenino , Pérdida Auditiva Bilateral/etiología , Pérdida Auditiva Sensorineural/etiología , Humanos , Lactante , Masculino , Estudios Retrospectivos
10.
Gait Posture ; 62: 206-213, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29571088

RESUMEN

BACKGROUND: Many stroke patients are inclined to consciously control their movements. This is thought to negatively affect patients' motor performance, as it disrupts movement automaticity. However, it has also been argued that conscious control may sometimes benefit motor performance, depending on the task or patients motor or cognitive capacity. AIM: To assess whether stroke patients' inclination for conscious control is associated with motor performance, and explore whether the putative association differs as a function of task (single- vs dual) or patients motor and cognitive capacity. METHODS: Univariate and multivariate linear regression analysis were used to assess associations between patients' disposition to conscious control (i.e., Conscious Motor Processing subscale of Movement-Specific Reinvestment Scale; MSRS-CMP) and single-task (Timed-up-and-go test; TuG) and motor dual-task costs (TuG while tone counting; motor DTC%). We determined whether these associations were influenced by patients' walking speed (i.e., 10-m-walk test) and cognitive capacity (i.e., working memory, attention, executive function). RESULTS: Seventy-eight clinical stroke patients (<6 months post-stroke) participated. Patients' conscious control inclination was not associated with single-task TuG performance. However, patients with a strong inclination for conscious control showed higher motor DTC%. These associations were irrespective of patients' motor and cognitive abilities. CONCLUSION: Patients' disposition for conscious control was not associated with single task motor performance, but was associated with higher motor dual task costs, regardless of patients' motor or cognitive abilities. CLINICAL RELEVANCE: Therapists should be aware that patients' conscious control inclination can influence their dual-task performance while moving. Longitudinal studies are required to test whether reducing patients' disposition for conscious control would improve dual-tasking post-stroke.


Asunto(s)
Concienciación/fisiología , Cognición/fisiología , Marcha/fisiología , Destreza Motora/fisiología , Desempeño Psicomotor , Accidente Cerebrovascular/fisiopatología , Adulto , Anciano , Atención/fisiología , Función Ejecutiva/fisiología , Femenino , Humanos , Masculino , Memoria a Corto Plazo/fisiología , Persona de Mediana Edad , Análisis de Regresión , Rehabilitación de Accidente Cerebrovascular , Análisis y Desempeño de Tareas
11.
Eur J Med Genet ; 60(9): 465-473, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28642162

RESUMEN

BACKGROUND: Several genetic causes of ectopia lentis (EL), with or without systemic features, are known. The differentiation between syndromic and isolated EL is crucial for further treatment, surveillance and counseling of patients and their relatives. Next generation sequencing (NGS) is a powerful tool enabling the simultaneous, highly-sensitive analysis of multiple target genes. OBJECTIVE: The aim of this study was to evaluate the diagnostic yield of our NGS panel in EL patients. Furthermore, we provide an overview of currently described mutations in ADAMTSL4, the main gene involved in isolated EL. METHODS: A NGS gene panel was analysed in 24 patients with EL. RESULTS: A genetic diagnosis was confirmed in 16 patients (67%). Of these, four (25%) had a heterozygous FBN1 mutation, 12 (75%) were homozygous or compound heterozygous for ADAMTSL4 mutations. The known European ADAMTSL4 founder mutation c.767_786del was most frequently detected. CONCLUSION: The diagnostic yield of our NGS panel was high. Causative mutations were exclusively identified in ADAMTSL4 and FBN1. With this approach the risk of misdiagnosis or delayed diagnosis can be reduced. The value and clinical implications of establishing a genetic diagnosis in patients with EL is corroborated by the description of two patients with an unexpected underlying genetic condition.


Asunto(s)
Desplazamiento del Cristalino/genética , Pruebas Genéticas/métodos , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Análisis de Secuencia de ADN/métodos , Proteínas ADAMTS/genética , Adolescente , Adulto , Anciano , Niño , Preescolar , Desplazamiento del Cristalino/diagnóstico , Reacciones Falso Positivas , Femenino , Pruebas Genéticas/normas , Secuenciación de Nucleótidos de Alto Rendimiento/normas , Humanos , Lactante , Masculino , Persona de Mediana Edad , Sensibilidad y Especificidad , Análisis de Secuencia de ADN/normas
12.
Int J Pediatr Otorhinolaryngol ; 97: 185-191, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28483233

RESUMEN

OBJECTIVE: Evaluation of causal abnormalities identified on CT and MR imaging in children with unilateral sensorineural hearing loss (USNHL), and the association with age and severity of hearing loss. STUDY DESIGN: Retrospective cohort study. SETTING: Tertiary referral otology/audiology center. PATIENTS AND DIAGNOSTIC INTERVENTIONS: 102 children diagnosed with USNHL between 2006 and 2016 were included. They underwent CT and/or MR imaging for the evaluation of the etiology of their hearing loss. MAIN OUTCOME MEASURES: Radiologic abnormalities of the inner ear and brain associated with USNHL. RESULTS: Using CT and/or MR imaging, causal abnormalities were identified in 49%, which is higher than previously reported (25-40%). The most frequently affected site was the labyrinth (29%), followed by the cochlear nerve (9%) and brain (7%). No significant difference in the number or type of abnormalities was found for the degree of hearing loss or age categories. CONCLUSIONS: Imaging is essential in the etiologic analysis of USNHL because of the high prevalence of causative abnormalities that can be identified with radiology, irrespective of the patients' age or degree of hearing loss. CT and MR imaging are complementary imaging options. The ideal imaging algorithm is controversial. Based on our findings, we conclude that there is limited additional diagnostic value of simultaneous dual modality imaging over sequential diagnostics. We therefore perform a stepwise radiological workup in order to maximize the diagnostic yield while minimizing impact and costs. If the primary imaging modality does not identify a cause for USNHL, performing the alternative imaging modality should be considered. LEVEL OF EVIDENCE: Retrospective cohort study 2b.


Asunto(s)
Encéfalo/patología , Oído Interno/patología , Pérdida Auditiva Sensorineural/etiología , Imagen por Resonancia Magnética/métodos , Tomografía Computarizada por Rayos X/métodos , Adolescente , Audiometría , Encéfalo/diagnóstico por imagen , Niño , Preescolar , Estudios de Cohortes , Oído Interno/diagnóstico por imagen , Femenino , Pérdida Auditiva Sensorineural/diagnóstico por imagen , Humanos , Lactante , Masculino , Países Bajos , Prevalencia , Estudios Retrospectivos , Centros de Atención Terciaria
13.
J Tissue Eng Regen Med ; 11(11): 2988-2998, 2017 11.
Artículo en Inglés | MEDLINE | ID: mdl-27641068

RESUMEN

Mesenchymal stem cells (MSC) are precursor cells of mesodermal tissue and, because of their trophic phenotype, they are known to play beneficial roles in wound healing. In addition, various tissue engineering strategies are based on MSC/biomaterial constructs. As the isolation and expansion of MSCs is a long-term process, a major goal is to develop an endogenous stem cell recruitment system that circumvents all ex vivo steps generally used for tissue engineering. Therefore collagen and silk fibroin were loaded with hepatocyte growth factor (HGF), a chemoattractant for MSCs. Collagen was mixed with HGF during polymerization, while silk fibroin and HGF were produced as fusion proteins by transgenic silkworms. To demonstrate release of active HGF, enzyme-linked immunosorbent assay, in vitro migration assays and animal studies were performed to demonstrate MSC migration in vivo, followed by detailed examinations of the immunological effects of the biomaterials. Hepatocyte growth factor was released burst-like, both from silk fibroin and collagen during the first 8 h and gradually for up to 168 h in vitro. Directed migration in vitro was demonstrated when MSCs were exposed to HGF. In vivo, HGF-loaded collagen and silk fibroin were tolerated as subcutaneous implants. In addition, it was proved that endogenous MSCs were recruited from the local environment. These results show for the first time recruitment of endogenous MSCs to HGF-loaded collagen (fast degradable) and silk fibroin scaffolds (long-term degradable) in vitro and in vivo. This knowledge could be applied to make off-the-shelf, readily available constructs for use in patients with chronic wound or burns. Copyright © 2016 John Wiley & Sons, Ltd.


Asunto(s)
Materiales Biocompatibles , Movimiento Celular/efectos de los fármacos , Factor de Crecimiento de Hepatocito , Células Madre Mesenquimatosas/metabolismo , Heridas y Lesiones/terapia , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacocinética , Materiales Biocompatibles/farmacología , Implantes de Medicamentos/química , Implantes de Medicamentos/farmacocinética , Implantes de Medicamentos/farmacología , Femenino , Fibroínas/química , Fibroínas/farmacocinética , Fibroínas/farmacología , Factor de Crecimiento de Hepatocito/química , Factor de Crecimiento de Hepatocito/farmacocinética , Factor de Crecimiento de Hepatocito/farmacología , Humanos , Masculino , Células Madre Mesenquimatosas/patología , Heridas y Lesiones/metabolismo , Heridas y Lesiones/patología
14.
PLoS One ; 11(12): e0166376, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27992442

RESUMEN

Many stroke patients experience difficulty with performing dual-tasks. A promising intervention to target this issue is implicit motor learning, as it should enhance patients' automaticity of movement. Yet, although it is often thought that implicit motor learning is preserved post-stroke, evidence for this claim has not been systematically analysed yet. Therefore, we systematically reviewed whether implicit motor learning is preserved post-stroke, and whether patients benefit more from implicit than from explicit motor learning. We comprehensively searched conventional (MEDLINE, Cochrane, Embase, PEDro, PsycINFO) and grey literature databases (BIOSIS, Web of Science, OpenGrey, British Library, trial registries) for relevant reports. Two independent reviewers screened reports, extracted data, and performed a risk of bias assessment. Overall, we included 20 out of the 2177 identified reports that allow for a succinct evaluation of implicit motor learning. Of these, only 1 study investigated learning on a relatively complex, whole-body (balance board) task. All 19 other studies concerned variants of the serial-reaction time paradigm, with most of these focusing on learning with the unaffected hand (N = 13) rather than the affected hand or both hands (both: N = 4). Four of the 20 studies compared explicit and implicit motor learning post-stroke. Meta-analyses suggest that patients with stroke can learn implicitly with their unaffected side (mean difference (MD) = 69 ms, 95% CI[45.1, 92.9], p < .00001), but not with their affected side (standardized MD = -.11, 95% CI[-.45, .25], p = .56). Finally, implicit motor learning seemed equally effective as explicit motor learning post-stroke (SMD = -.54, 95% CI[-1.37, .29], p = .20). However, overall, the high risk of bias, small samples, and limited clinical relevance of most studies make it impossible to draw reliable conclusions regarding the effect of implicit motor learning strategies post-stroke. High quality studies with larger samples are warranted to test implicit motor learning in clinically relevant contexts.


Asunto(s)
Aprendizaje/fisiología , Destreza Motora/fisiología , Accidente Cerebrovascular/fisiopatología , Anciano , Humanos , Persona de Mediana Edad , Tiempo de Reacción , Recuperación de la Función , Accidente Cerebrovascular/psicología , Rehabilitación de Accidente Cerebrovascular
15.
J Mot Behav ; 48(6): 527-534, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27340947

RESUMEN

The authors investigated the relative effectiveness of different attentional focus instructions on motor learning in primary school children. In addition, we explored whether the effect of attentional focus on motor learning was influenced by children's age and verbal working memory capacity. Novice 8-9-year old children (n = 30) and 11-12-year-old children (n = 30) practiced a golf putting task. For each age group, half the participants received instructions to focus (internally) on the swing of their arm, while the other half was instructed to focus (externally) on the swing of the club. Children's verbal working memory capacity was assessed with the Automated Working Memory Assessment. Consistent with many reports on adult's motor learning, children in the external groups demonstrated greater improvements in putting accuracy than children who practiced with an internal focus. This effect was similar across age groups. Verbal working memory capacity was not found to be predictive of motor learning, neither for children in the internal focus groups nor for children in the external focus groups. In conclusion, primary school children's motor learning is enhanced by external focus instructions compared to internal focus instructions. The purported modulatory roles of children's working memory, attentional capacity, or focus preferences require further investigation.


Asunto(s)
Envejecimiento/fisiología , Envejecimiento/psicología , Atención/fisiología , Aprendizaje/fisiología , Memoria a Corto Plazo/fisiología , Destreza Motora/fisiología , Niño , Femenino , Golf , Humanos , Masculino , Educación y Entrenamiento Físico/métodos
16.
Disabil Rehabil ; 38(11): 1097-106, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26752361

RESUMEN

PURPOSE: Stroke survivors are inclined to consciously control their movements, a phenomenon termed "reinvestment". Preliminary evidence suggests reinvestment to impair patients' motor recovery. To investigate this hypothesis, an instrument is needed that can reliably assess reinvestment post-stroke. Therefore, this study aimed to validate the Movement-Specific Reinvestment Scale (MSRS) within inpatient stroke patients. METHOD: One-hundred inpatient stroke patients (<1 year post-stroke) and 100 healthy peers completed the MSRS, which was translated to Dutch for the study purpose. To assess structural validity, confirmatory factor analysis determined whether the scale measures two latent constructs, as previously reported in healthy adults. Construct validity was determined by testing whether patients had higher reinvestment than controls. Reliability analyses entailed assessment of retest reliability (ICC), internal consistency (Cronbach's alpha), and minimal detectable change. RESULTS: Both structural and construct validity of the MSRS were supported. Retest reliability and internal consistency indices were acceptable to good. The minimal detectable change was adequate on group level, but considerable on individual level. CONCLUSIONS: The MSRS is a valid and reliable tool and suitable to assess the relationship between reinvestment and motor recovery in the first months post-stroke. Eventually, this may help therapists to individualize motor learning interventions based on patients' reinvestment preferences. IMPLICATIONS FOR REHABILITATION: This study showed that the Movement-Specific Reinvestment Scale (MSRS) is a valid and reliable tool to objectify stroke patients' inclination for conscious motor control. The MSRS may be used to identify stroke patients who are strongly inclined to consciously control their movements, as this disposition may hinder their motor recovery. Eventually, the MSRS may enable clinicians to tailor motor learning interventions to stroke patients' motor control preferences.


Asunto(s)
Modalidades de Fisioterapia , Desempeño Psicomotor , Recuperación de la Función , Rehabilitación de Accidente Cerebrovascular , Accidente Cerebrovascular , Anciano , Evaluación de la Discapacidad , Personas con Discapacidad/psicología , Personas con Discapacidad/rehabilitación , Femenino , Humanos , Pacientes Internos/estadística & datos numéricos , Masculino , Persona de Mediana Edad , Países Bajos , Psicometría/métodos , Reproducibilidad de los Resultados , Accidente Cerebrovascular/diagnóstico , Accidente Cerebrovascular/fisiopatología , Accidente Cerebrovascular/psicología , Rehabilitación de Accidente Cerebrovascular/métodos , Rehabilitación de Accidente Cerebrovascular/psicología , Traducción , Resultado del Tratamiento , Escala Visual Analógica
17.
PLoS One ; 10(8): e0136917, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26317437

RESUMEN

Dual-task performance is often impaired after stroke. This may be resolved by enhancing patients' automaticity of movement. This study sets out to test the constrained action hypothesis, which holds that automaticity of movement is enhanced by triggering an external focus (on movement effects), rather than an internal focus (on movement execution). Thirty-nine individuals with chronic, unilateral stroke performed a one-leg-stepping task with both legs in single- and dual-task conditions. Attentional focus was manipulated with instructions. Motor performance (movement speed), movement automaticity (fluency of movement), and dual-task performance (dual-task costs) were assessed. The effects of focus on movement speed, single- and dual-task movement fluency, and dual-task costs were analysed with generalized estimating equations. Results showed that, overall, single-task performance was unaffected by focus (p = .341). Regarding movement fluency, no main effects of focus were found in single- or dual-task conditions (p's ≥ .13). However, focus by leg interactions suggested that an external focus reduced movement fluency of the paretic leg compared to an internal focus (single-task conditions: p = .068; dual-task conditions: p = .084). An external focus also tended to result in inferior dual-task performance (ß = -2.38, p = .065). Finally, a near-significant interaction (ß = 2.36, p = .055) suggested that dual-task performance was more constrained by patients' attentional capacity in external focus conditions. We conclude that, compared to an internal focus, an external focus did not result in more automated movements in chronic stroke patients. Contrary to expectations, trends were found for enhanced automaticity with an internal focus. These findings might be due to patients' strong preference to use an internal focus in daily life. Future work needs to establish the more permanent effects of learning with different attentional foci on re-automating motor control after stroke.


Asunto(s)
Atención/fisiología , Movimiento/fisiología , Accidente Cerebrovascular/psicología , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Desempeño Psicomotor/fisiología , Accidente Cerebrovascular/fisiopatología , Análisis y Desempeño de Tareas
18.
Clin Genet ; 87(2): 141-7, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24597975

RESUMEN

The BCAP31 gene is located between SLC6A8, associated with X-linked creatine transporter deficiency, and ABCD1, associated with X-linked adrenoleukodystrophy. Recently, loss-of-function mutations in BCAP31 were reported in association with severe developmental delay, deafness and dystonia. We characterized the break points in eight patients with deletions of SLC6A8, BCAP31 and/or ABCD1 and studied the genotype-phenotype correlations. The phenotype in patients with contiguous gene deletions involving BCAP31 overlaps with the phenotype of isolated BCAP31 deficiency. Only deletions involving both BCAP31 and ABCD1 were associated with hepatic cholestasis and death before 1 year, which might be explained by a synergistic effect. Remarkably, a patient with an isolated deletion at the 3'-end of SLC6A8 had a similar severe phenotype as seen in BCAP31 deficiency but without deafness. This might be caused by the disturbance of a regulatory element between SLC6A8 and BCAP31.


Asunto(s)
Transportadoras de Casetes de Unión a ATP/genética , Colestasis Intrahepática/genética , Discapacidad Intelectual/genética , Proteínas de la Membrana/genética , Proteínas del Tejido Nervioso/genética , Proteínas de Transporte de Neurotransmisores en la Membrana Plasmática/genética , Miembro 1 de la Subfamilia D de Transportador de Casetes de Unión al ATP , Adrenoleucodistrofia/genética , Adrenoleucodistrofia/mortalidad , Adrenoleucodistrofia/patología , Adulto , Encefalopatías Metabólicas Innatas/genética , Encefalopatías Metabólicas Innatas/mortalidad , Encefalopatías Metabólicas Innatas/patología , Niño , Preescolar , Colestasis Intrahepática/mortalidad , Colestasis Intrahepática/patología , Creatina/deficiencia , Creatina/genética , Eliminación de Gen , Estudios de Asociación Genética , Humanos , Lactante , Recién Nacido , Discapacidad Intelectual/mortalidad , Discapacidad Intelectual/patología , Masculino , Discapacidad Intelectual Ligada al Cromosoma X/genética , Discapacidad Intelectual Ligada al Cromosoma X/mortalidad , Discapacidad Intelectual Ligada al Cromosoma X/patología , Fenotipo , Proteínas de Transporte de Neurotransmisores en la Membrana Plasmática/deficiencia
19.
Eur J Radiol ; 82(12): 2265-9, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24075785

RESUMEN

OBJECTIVES: To compare the long-term outcome after uterine artery embolization (UAE) versus magnetic resonance-guided high-intensity focused ultrasound (MR-g HIFU) for symptomatic uterine fibroids. METHODS: Seventy-seven women (median age, 39.3 years; range, 29.2-52.2 years) with symptomatic uterine fibroids, equally eligible for UAE and MR-g HIFU based on our exclusion criteria underwent treatment (UAE, N = 41; MR-g HIFU, N = 36) from 2002 to 2009 at our institution. Symptom severity (SS) and total health-related quality of life (Total HRQoL) scores were assessed by the uterine fibroid symptom and quality of life (UFS-QoL) questionnaire before treatment and at long-term follow-up after UAE (median 61.9 months) and after MR-g HIFU (median: 60.7 months). Re-intervention rates were assessed for each therapy and compared. RESULTS: Re-intervention was significantly lower after UAE (12.2%) than after MR-g HIFU (66.7%) at long-term follow-up (p<0.001). After UAE changes in SS (50 pre-treatment vs. 6.3 post-treatment) and Total HRQoL (57.8 pre-treatment vs. 100 post-treatment) were significantly better than changes in SS (42.2 pre-treatment vs. 26.6 post-treatment) and Total HRQoL score (66.4 pre-treatment vs. 87.9 post-treatment) after MR-g HIFU (p = 0.019 and 0.049 respectively). CONCLUSIONS: Improvement of SS and Total HRQoL scores was significantly better after UAE resulting in a significant lower re-intervention rate compared to MR-g HIFU.


Asunto(s)
Ultrasonido Enfocado de Alta Intensidad de Ablación/métodos , Leiomioma/patología , Leiomioma/terapia , Imagen por Resonancia Magnética/métodos , Embolización de la Arteria Uterina/métodos , Neoplasias Uterinas/patología , Neoplasias Uterinas/terapia , Adulto , Femenino , Humanos , Estudios Longitudinales , Persona de Mediana Edad , Cirugía Asistida por Computador/métodos , Resultado del Tratamiento
20.
Hum Mov Sci ; 32(4): 527-39, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24054892

RESUMEN

An external focus of attention has been shown to result in superior motor performance compared to an internal focus of attention. This study investigated whether this is due to enhanced levels of movement automatization, as predicted by the constrained action hypothesis (McNevin, Shea, & Wulf, 2003). Thirty healthy participants performed a cyclic one-leg extension-flexion task with both the dominant and non-dominant leg. Focus of attention was manipulated via instructions. The degree of automatization of movement was assessed by measuring dual task costs as well as movement execution parameters (i.e., EMG activity, movement fluency, and movement regularity). Results revealed that an external focus of attention led to significantly better motor performance (i.e., shorter movement duration) than an internal focus. Although dual task costs of the motor task did not differ as a function of attentional focus, cognitive dual task costs were significantly higher when attention was directed internally. An external focus of attention resulted in more fluent and more regular movement execution than an internal focus, whereas no differences were found concerning muscular activity. These results indicate that an external focus of attention results in more automatized movements than an internal focus and, therefore, provide support for the constrained action hypothesis.


Asunto(s)
Atención/fisiología , Automatismo/fisiopatología , Electromiografía , Control Interno-Externo , Movimiento/fisiología , Músculo Esquelético/fisiopatología , Adulto , Femenino , Lateralidad Funcional/fisiología , Humanos , Masculino , Destreza Motora/fisiología , Desempeño Psicomotor/fisiología , Adulto Joven
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