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1.
Nature ; 610(7930): 112-119, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-36131019

RESUMEN

The history of the British Isles and Ireland is characterized by multiple periods of major cultural change, including the influential transformation after the end of Roman rule, which precipitated shifts in language, settlement patterns and material culture1. The extent to which migration from continental Europe mediated these transitions is a matter of long-standing debate2-4. Here we study genome-wide ancient DNA from 460 medieval northwestern Europeans-including 278 individuals from England-alongside archaeological data, to infer contemporary population dynamics. We identify a substantial increase of continental northern European ancestry in early medieval England, which is closely related to the early medieval and present-day inhabitants of Germany and Denmark, implying large-scale substantial migration across the North Sea into Britain during the Early Middle Ages. As a result, the individuals who we analysed from eastern England derived up to 76% of their ancestry from the continental North Sea zone, albeit with substantial regional variation and heterogeneity within sites. We show that women with immigrant ancestry were more often furnished with grave goods than women with local ancestry, whereas men with weapons were as likely not to be of immigrant ancestry. A comparison with present-day Britain indicates that subsequent demographic events reduced the fraction of continental northern European ancestry while introducing further ancestry components into the English gene pool, including substantial southwestern European ancestry most closely related to that seen in Iron Age France5,6.


Asunto(s)
Pool de Genes , Migración Humana , Arqueología , ADN Antiguo/análisis , Dinamarca , Inglaterra , Femenino , Francia , Genética de Población , Genoma Humano/genética , Alemania , Historia Medieval , Migración Humana/historia , Humanos , Lenguaje , Masculino , Dinámica Poblacional , Armas/historia
2.
Haematologica ; 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38721749

RESUMEN

Promoting access to and excellence in hematopoietic cell transplantation (HCT) by collecting and disseminating data on global HCT activities is one of the principal activities of the Worldwide Network for Blood and Marrow Transplantation, a non-Governmental organization in working relations with the World Health Organization. HCT activities are recorded annually by member societies, national registries and individual centers including indication, donor type (allogeneic/autologous), donor match and stem cell source (bone marrow/peripheral blood stem cells/cord blood). In 2018, 1,768 HCT teams in 89 countries (six WHO regions) reported 93,105 (48,680 autologous and 44,425 allogeneic) HCT. Major indications were plasma cell disorders and lymphoma for autologous, and acute leukemias and MDS/MPN for allogeneic HCT. HCT number increased from 48,709 in 2007. Notable increases were seen for autoimmune diseases in autologous and hemoglobinopathies in allogeneic HCT. The number of allogeneic HCT more than doubled with significant changes in donor match. While HCT from HLA identical siblings has seen only limited growth, HCT from non-identical related donors showed significant increase worldwide. Strongest correlation between economic growth indicator of gross national income/capita and HCT activity/ten million population was observed for autologous HCT (r=0.79). HCT from unrelated donors showed strong correlation (r=0.68), but only moderate correlation (r=0.51) was detected from related donors. The use of HCT doubled in about a decade worldwide at different speed and with significant changes regarding donor match as a sign of improved access to HCT worldwide. Although narrowing, significant gaps remain between developing and non-developing countries.

3.
RNA Biol ; 21(1): 1-11, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38112323

RESUMEN

Epithelial-mesenchymal transition (EMT) plays important roles in tumour progression and is orchestrated by dynamic changes in gene expression. While it is well established that post-transcriptional regulation plays a significant role in EMT, the extent of alternative polyadenylation (APA) during EMT has not yet been explored. Using 3' end anchored RNA sequencing, we mapped the alternative polyadenylation (APA) landscape following Transforming Growth Factor (TGF)-ß-mediated induction of EMT in human mammary epithelial cells and found APA generally causes 3'UTR lengthening during this cell state transition. Investigation of potential mediators of APA indicated the RNA-binding protein Quaking (QKI), a splicing factor induced during EMT, regulates a subset of events including the length of its own transcript. Analysis of QKI crosslinked immunoprecipitation (CLIP)-sequencing data identified the binding of QKI within 3' untranslated regions (UTRs) was enriched near cleavage and polyadenylation sites. Following QKI knockdown, APA of many transcripts is altered to produce predominantly shorter 3'UTRs associated with reduced gene expression. These findings reveal the changes in APA that occur during EMT and identify a potential role for QKI in this process.


Asunto(s)
Regulación de la Expresión Génica , Poliadenilación , Humanos , Transición Epitelial-Mesenquimal/genética , Secuencia de Bases , Proteínas de Unión al ARN/genética , Regiones no Traducidas 3'
4.
Artículo en Alemán | MEDLINE | ID: mdl-38750238

RESUMEN

Medication analyses by ward pharmacists are an important measure of drug therapy safety (DTS). Medication-related problems (MRPs) are identified and resolved with the attending clinicians. However, staff resources for extended medication analyses and complete documentation are often limited. Until now, data required for the identification of risk patients and for an extended medication analysis often had to be collected from various parts of the institution's internal electronic medical record (EMR). This error-prone and time-consuming process is to be improved in the INTERPOLAR (INTERventional POLypharmacy-Drug interActions-Risks) project using an IT tool provided by the data integration centers (DIC).INTERPOLAR is a use case of the Medical Informatics Initiative (MII) that focuses on the topic of DTS. The planning phase took place in 2023, with routine implementation planned from 2024. DTS-relevant data from the EMR is to be presented and the documentation of MRPs in routine care is to be facilitated. The prospective multicenter, cluster-randomized INTERPOLAR­1 study serves to evaluate the benefits of IT support in routine care. The aim is to show that more MRPs can be detected and resolved with the help of IT support. For this purpose, six normal wards will be selected at each of eight university hospitals, so that 48 clusters (with a total of at least 70,000 cases) are available for randomization.


Asunto(s)
Errores de Medicación , Humanos , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/prevención & control , Registros Electrónicos de Salud , Alemania , Informática Médica , Errores de Medicación/prevención & control , Seguridad del Paciente , Estudios Prospectivos , Mejoramiento de la Calidad
6.
EMBO J ; 37(13)2018 07 02.
Artículo en Inglés | MEDLINE | ID: mdl-29871889

RESUMEN

Members of the miR-200 family are critical gatekeepers of the epithelial state, restraining expression of pro-mesenchymal genes that drive epithelial-mesenchymal transition (EMT) and contribute to metastatic cancer progression. Here, we show that miR-200c and another epithelial-enriched miRNA, miR-375, exert widespread control of alternative splicing in cancer cells by suppressing the RNA-binding protein Quaking (QKI). During EMT, QKI-5 directly binds to and regulates hundreds of alternative splicing targets and exerts pleiotropic effects, such as increasing cell migration and invasion and restraining tumour growth, without appreciably affecting mRNA levels. QKI-5 is both necessary and sufficient to direct EMT-associated alternative splicing changes, and this splicing signature is broadly conserved across many epithelial-derived cancer types. Importantly, several actin cytoskeleton-associated genes are directly targeted by both QKI and miR-200c, revealing coordinated control of alternative splicing and mRNA abundance during EMT These findings demonstrate the existence of a miR-200/miR-375/QKI axis that impacts cancer-associated epithelial cell plasticity through widespread control of alternative splicing.


Asunto(s)
Empalme Alternativo/fisiología , Plasticidad de la Célula/fisiología , Transición Epitelial-Mesenquimal/fisiología , MicroARNs/fisiología , Proteínas de Unión al ARN/fisiología , Animales , Línea Celular Tumoral , Movimiento Celular , Perros , Humanos , Células de Riñón Canino Madin Darby , Ratones SCID
7.
BMC Med Inform Decis Mak ; 22(1): 112, 2022 04 27.
Artículo en Inglés | MEDLINE | ID: mdl-35477495

RESUMEN

BACKGROUND: Wearables, as small portable computer systems worn on the body, can track user fitness and health data, which can be used to customize health insurance contributions individually. In particular, insured individuals with a healthy lifestyle can receive a reduction of their contributions to be paid. However, this potential is hardly used in practice. OBJECTIVE: This study aims to identify which barrier factors impede the usage of wearables for assessing individual risk scores for health insurances, despite its technological feasibility, and to rank these barriers according to their relevance. METHODS: To reach these goals, we conduct a ranking-type Delphi study with the following three stages. First, we collected possible barrier factors from a panel of 16 experts and consolidated them to a list of 11 barrier categories. Second, the panel was asked to rank them regarding their relevance. Third, to enhance the panel consensus, the ranking was revealed to the experts, who were then asked to re-rank the barriers. RESULTS: The results suggest that regulation is the most important barrier. Other relevant barriers are false or inaccurate measurements and application errors caused by the users. Additionally, insurers could lack the required technological competence to use the wearable data appropriately. CONCLUSION: A wider use of wearables and health apps could be achieved through regulatory modifications, especially regarding privacy issues. Even after assuring stricter regulations, users' privacy concerns could partly remain, if the data exchange between wearables manufacturers, health app providers, and health insurers does not become more transparent.


Asunto(s)
Seguro de Salud , Dispositivos Electrónicos Vestibles , Ejercicio Físico , Humanos , Privacidad
8.
Semin Cell Dev Biol ; 75: 50-60, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-28789987

RESUMEN

Interconversions between epithelial and mesenchymal states, often referred to as epithelial mesenchymal transition (EMT) and its reverse MET, play important roles in embryonic development and are recapitulated in various adult pathologies including cancer progression. These conversions are regulated by complex transcriptional and post-transcriptional mechanisms including programs of alternative splicing which are orchestrated by specific splicing factors. This review will focus on the latest developments in our understanding of the splicing factors regulating epithelial mesenchymal plasticity associated with cancer progression and the induction of pluripotency, including potential roles for circular RNAs (circRNAs) which have been recently implicated in these processes.


Asunto(s)
Empalme Alternativo , Transición Epitelial-Mesenquimal/genética , Regulación de la Expresión Génica , ARN/genética , Animales , Humanos , Modelos Genéticos , Isoformas de ARN/genética , Precursores del ARN/genética , Precursores del ARN/metabolismo , ARN Circular , Proteínas de Unión al ARN/genética , Proteínas de Unión al ARN/metabolismo
9.
EMBO J ; 35(4): 402-13, 2016 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-26783364

RESUMEN

The Bcl-2 family proteins Bax and Bak are essential for the execution of many apoptotic programs. During apoptosis, Bax translocates to the mitochondria and mediates the permeabilization of the outer membrane, thereby facilitating the release of pro-apoptotic proteins. Yet the mechanistic details of the Bax-induced membrane permeabilization have so far remained elusive. Here, we demonstrate that activated Bax molecules, besides forming large and compact clusters, also assemble, potentially with other proteins including Bak, into ring-like structures in the mitochondrial outer membrane. STED nanoscopy indicates that the area enclosed by a Bax ring is devoid of mitochondrial outer membrane proteins such as Tom20, Tom22, and Sam50. This strongly supports the view that the Bax rings surround an opening required for mitochondrial outer membrane permeabilization (MOMP). Even though these Bax assemblies may be necessary for MOMP, we demonstrate that at least in Drp1 knockdown cells, these assemblies are not sufficient for full cytochrome c release. Together, our super-resolution data provide direct evidence in support of large Bax-delineated pores in the mitochondrial outer membrane as being crucial for Bax-mediated MOMP in cells.


Asunto(s)
Apoptosis , Mitocondrias/enzimología , Membranas Mitocondriales/metabolismo , Proteínas Citotóxicas Formadoras de Poros/metabolismo , Multimerización de Proteína , Proteína X Asociada a bcl-2/metabolismo , Línea Celular , Citocromos c/metabolismo , Humanos , Microscopía Fluorescente , Mitocondrias/fisiología , Membranas Mitocondriales/fisiología , Permeabilidad
10.
Magn Reson Med ; 75(3): 1086-99, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25845973

RESUMEN

PURPOSE: Phase-constrained parallel MRI approaches have the potential for significantly improving the image quality of accelerated MRI scans. The purpose of this study was to investigate the properties of two different phase-constrained parallel MRI formulations, namely the standard phase-constrained approach and the virtual conjugate coil (VCC) concept utilizing conjugate k-space symmetry. METHODS: Both formulations were combined with image-domain algorithms (SENSE) and a mathematical analysis was performed. Furthermore, the VCC concept was combined with k-space algorithms (GRAPPA and ESPIRiT) for image reconstruction. In vivo experiments were conducted to illustrate analogies and differences between the individual methods. Furthermore, a simple method of improving the signal-to-noise ratio by modifying the sampling scheme was implemented. RESULTS: For SENSE, the VCC concept was mathematically equivalent to the standard phase-constrained formulation and therefore yielded identical results. In conjunction with k-space algorithms, the VCC concept provided more robust results when only a limited amount of calibration data were available. Additionally, VCC-GRAPPA reconstructed images provided spatial phase information with full resolution. CONCLUSIONS: Although both phase-constrained parallel MRI formulations are very similar conceptually, there exist important differences between image-domain and k-space domain reconstructions regarding the calibration robustness and the availability of high-resolution phase information.


Asunto(s)
Algoritmos , Procesamiento de Imagen Asistido por Computador/métodos , Imagen por Resonancia Magnética/métodos , Procesamiento de Señales Asistido por Computador , Imagen por Resonancia Magnética/instrumentación
11.
Arch Toxicol ; 90(11): 2745-2761, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26525392

RESUMEN

Predictive test systems to assess the mode of action of chemical carcinogens are urgently required. Within the present study, we applied the Fluidigm dynamic array on the BioMark™ HD System for quantitative high-throughput RT-qPCR analysis of 95 genes and 96 samples in parallel, selecting genes crucial for maintaining genomic stability, including stress response as well as DNA repair, cell cycle control, apoptosis and mitotic signaling. The specificity of each individually designed sequence-specific primer pair and their respective target amplicons were evaluated via melting curve analysis as part of qPCR and size verification via agarose gel electrophoresis. For each gene, calibration curves displayed high efficiencies and correlation coefficients in the identified linear dynamic range as well as low intra-assay variations. Data were processed via Fluidigm real-time PCR analysis and GenEx software, and results were depicted as relative gene expression according to the ΔΔC q method. Subsequently, gene expression analyses were conducted in cadmium-treated adenocarcinoma A549 and epithelial bronchial BEAS-2B cells. They revealed distinct dose- and time-dependent and also cell-type-specific gene expression patterns, including the induction of genes coding for metallothioneins, the oxidative stress response, cell cycle control, mitotic signaling and apoptosis. Interestingly, while genes coding for the DNA damage response were induced, distinct DNA repair genes were down-regulated at the transcriptional level. Thus, this approach provided a comprehensive overview on the interaction by cadmium with distinct signaling pathways, also reflecting molecular modes of action in cadmium-induced carcinogenicity. Therefore, the test system appears to be a promising tool for toxicological risk assessment.


Asunto(s)
Adenocarcinoma Bronquioloalveolar/inducido químicamente , Cadmio/toxicidad , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Inestabilidad Genómica/efectos de los fármacos , Neoplasias Pulmonares/inducido químicamente , Mutágenos/toxicidad , Mucosa Respiratoria/efectos de los fármacos , Células A549 , Adenocarcinoma Bronquioloalveolar/metabolismo , Adenocarcinoma Bronquioloalveolar/patología , Proteínas Reguladoras de la Apoptosis/agonistas , Proteínas Reguladoras de la Apoptosis/antagonistas & inhibidores , Proteínas Reguladoras de la Apoptosis/genética , Proteínas Reguladoras de la Apoptosis/metabolismo , Calibración , Línea Celular , Perfilación de la Expresión Génica , Ensayos Analíticos de Alto Rendimiento , Humanos , Cinética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patología , Proteínas de Neoplasias/agonistas , Proteínas de Neoplasias/antagonistas & inhibidores , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Análisis de Secuencia por Matrices de Oligonucleótidos , Reacción en Cadena en Tiempo Real de la Polimerasa , Reproducibilidad de los Resultados , Mucosa Respiratoria/metabolismo , Mucosa Respiratoria/patología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
12.
Ann Otol Rhinol Laryngol ; 124(10): 803-7, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25944597

RESUMEN

OBJECTIVE: While generally well tolerated for the treatment of severe laryngomalacia, bilateral supraglottoplasty has potential complications including supraglottic stenosis and aspiration. We report a more conservative staged supraglottoplasty in infants with severe laryngomalacia. METHODS: A retrospective review was performed of our patients who underwent staged supraglottoplasty from June 2007 to June 2012. Fifteen infants were identified and scored based on stridor, retractions, oxygen saturation, and feeding quality. Outcomes were compared with those reported in the literature for conventional bilateral supraglottoplasty. RESULTS: Seventy-three percent had significant improvement or resolution of stridor following the first stage of surgery and 100% in those undergoing a second stage. Twelve patients (80%) had mild to no retractions following one procedure and 100% had resolution after a second surgery. All 6 patients with recurrent preoperative desaturations had resolution after the first stage of surgery. Of the 11 infants who had preoperative moderate-severe feeding problems, 9 of them (82%) had resolution after one surgery and the remaining 2 had resolution after a second surgery. There were no complications in any of the patients. CONCLUSIONS: Staged supraglottoplasty appears to be an effective, low-risk method to treat severe laryngomalacia. A second procedure was only required in 40% of patients.


Asunto(s)
Laringomalacia , Laringoplastia , Epiglotis/patología , Epiglotis/cirugía , Métodos de Alimentación , Femenino , Glotis/patología , Glotis/cirugía , Humanos , Lactante , Laringomalacia/complicaciones , Laringomalacia/congénito , Laringomalacia/metabolismo , Laringomalacia/fisiopatología , Laringomalacia/cirugía , Laringoplastia/efectos adversos , Laringoplastia/métodos , Masculino , Consumo de Oxígeno , Periodo Posoperatorio , Ruidos Respiratorios/etiología , Ruidos Respiratorios/fisiopatología , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Resultado del Tratamiento
13.
Magn Reson Med ; 72(6): 1680-6, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24436227

RESUMEN

PURPOSE: Cartesian turbo spin-echo (TSE) and radial TSE images are usually reconstructed by assembling data containing different contrast information into a single k-space. This approach results in mixed contrast contributions in the images, which may reduce their diagnostic value. The goal of this work is to improve the image contrast from radial TSE acquisitions by reducing the contribution of signals with undesired contrast information. METHODS: Radial TSE acquisitions allow the reconstruction of multiple images with different T2 contrasts using the k-space weighted image contrast (KWIC) filter. In this work, the image contrast is improved by reducing the band-width of the KWIC filter. Data for the reconstruction of a single image are selected from within a small temporal range around the desired echo time. The resulting dataset is undersampled and, therefore, an iterative parallel imaging algorithm is applied to remove aliasing artifacts. RESULTS: Radial TSE images of the human brain reconstructed with the proposed method show an improved contrast when compared with Cartesian TSE images or radial TSE images with conventional KWIC reconstructions. CONCLUSION: The proposed method provides multi-contrast images from radial TSE data with contrasts similar to multi spin-echo images. Contaminations from unwanted contrast weightings are strongly reduced.


Asunto(s)
Algoritmos , Artefactos , Encéfalo/anatomía & histología , Imagen Eco-Planar/métodos , Aumento de la Imagen/métodos , Interpretación de Imagen Asistida por Computador/métodos , Técnica de Sustracción , Humanos , Movimiento (Física) , Reproducibilidad de los Resultados , Tamaño de la Muestra , Sensibilidad y Especificidad , Procesamiento de Señales Asistido por Computador , Marcadores de Spin
14.
MAGMA ; 27(6): 567-77, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24643838

RESUMEN

OBJECTIVE: The quantification of magnetic resonance relaxation parameters T 1 and T 2 have the potential for improved disease detection and classification over standard clinical weighted imaging. Performing a mono-exponential fit on multi spin-echo (MSE) data provides quantitative T 2 values in a clinically acceptable scan-time. However, due to technical imperfections of refocusing pulses, stimulated echo contributions to the signals lead to significant deviations in the resulting T 2 values. In this work, a simple auto-calibrating correction procedure is presented, allowing the accurate estimation of T 2 from MSE acquisitions. MATERIALS AND METHODS: Correction factors for T 2 values obtained from MSE acquisitions with a mono-exponential fit are derived from simulations following the extended phase graph formulation. A closed formula is given for the calculation of the required correction factors directly from the measured data itself. RESULTS: Simulations and phantom experiments show high accuracy of corrected T 2 values for a wide range of clinically relevant T 2 values and for different nominal refocusing flip angles. In addition, corrected T 2 maps of the human brain are presented. CONCLUSION: A simple recipe is provided to correct T 2 values obtained from MSE acquisitions via a mono-exponential fit for the influence of stimulated echoes. Since all required parameters are extracted from the data themselves, no additional acquisitions are required.


Asunto(s)
Algoritmos , Artefactos , Encéfalo/anatomía & histología , Imagen Eco-Planar/métodos , Aumento de la Imagen/métodos , Interpretación de Imagen Asistida por Computador/métodos , Procesamiento de Señales Asistido por Computador , Imagen Eco-Planar/instrumentación , Humanos , Análisis Numérico Asistido por Computador , Fantasmas de Imagen , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
15.
Proc Natl Acad Sci U S A ; 108(33): 13546-51, 2011 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-21799113

RESUMEN

The translocase of the mitochondrial outer membrane (TOM) complex is the main import pore for nuclear-encoded proteins into mitochondria, yet little is known about its spatial distribution within the outer membrane. Super-resolution stimulated emission depletion microscopy was used to determine quantitatively the nanoscale distribution of Tom20, a subunit of the TOM complex, in more than 1,000 cells. We demonstrate that Tom20 is located in clusters whose nanoscale distribution is finely adjusted to the cellular growth conditions as well as to the specific position of a cell within a microcolony. The density of the clusters correlates to the mitochondrial membrane potential. The distributions of clusters of Tom20 and of Tom22 follow an inner-cellular gradient from the perinuclear to the peripheral mitochondria. We conclude that the nanoscale distribution of the TOM complex is finely adjusted to the cellular conditions, resulting in distribution gradients both within single cells and between adjacent cells.


Asunto(s)
Mitocondrias/metabolismo , Proteínas Mitocondriales/análisis , Receptores Citoplasmáticos y Nucleares/metabolismo , Animales , Línea Celular , Fenómenos Fisiológicos Celulares , Proteínas de Transporte de Membrana , Proteínas de Transporte de Membrana Mitocondrial/análisis , Proteínas de Transporte de Membrana Mitocondrial/metabolismo , Membranas Mitocondriales/metabolismo , Proteínas del Complejo de Importación de Proteínas Precursoras Mitocondriales , Proteínas Mitocondriales/metabolismo , Ratas , Receptores de Superficie Celular , Receptores Citoplasmáticos y Nucleares/análisis , Tubulina (Proteína)/análisis , Tubulina (Proteína)/metabolismo
16.
J Arthroplasty ; 29(4): 831-5, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24099841

RESUMEN

This study compared the corrosion behavior of tantalum-coated cobalt-chromium modular necks with that of titanium alloy modular necks at their junction to titanium-alloy femoral stem. Tests were performed in a dry assembly and two wet assemblies, one contaminated with calf serum and the other contaminated with calf serum and bone particles. Whereas the titanium modular neck tested in the dry assembly showed no signs of corrosion, the titanium modular necks tested in both wet assemblies showed marked depositions and corrosive attacks. By contrast, the tantalum-coated cobalt-chromium modular necks showed no traces of corrosion or chemical attack in any of the three assemblies. This study confirms the protective effect of tantalum coating the taper region of cobalt-chromium modular neck components, suggesting that the use of tantalum may reduce the risk of implant failure due to corrosion.


Asunto(s)
Prótesis de Cadera , Diseño de Prótesis , Falla de Prótesis , Artroplastia de Reemplazo de Cadera , Materiales Biocompatibles , Fenómenos Biomecánicos , Aleaciones de Cromo , Corrosión , Estrés Mecánico , Tantalio , Titanio
17.
Zoo Biol ; 33(3): 234-44, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24752991

RESUMEN

The Spix's macaw (Cyanopsitta spixii) is the rarest parrot on earth. The remaining captive population consists of 79 individuals. Captive propagation is ongoing to increase the number of individuals for future reintroduction back into the wild. Unfortunately, from 2004 to 2012, only 33 chicks hatched from 331 eggs. Semen evaluation and assisted reproduction might help to overcome this problem. Therefore, a recently developed electro-stimulated semen collection technique was used in Spix's macaws. Semen collection was successful in 39 of 78 attempts in 10 out of 17 males. Examination of the semen included evaluation of volume, color, consistency, contaminations and pH, as well as determination of motility, viability, morphology, concentration, and total count of spermatozoa. The median volume of semen samples was 5.6 µl. On average, 34.7 ± 21.9% (median 30%) of the sperm were motile and 23.1 ± 22.1% (median 16.5%) were progressively motile. In addition to spermatozoa, round cells were detected in the samples. Median sperm concentration was 15,500/µl (range 500-97,500/µl) and median viability was 50% (range 5-87%). Morphological examination revealed in 26.5% normal spermatozoa, high numbers of malformations of the head (50.2%) and tail region (20.5%), with 29% of all sperm showing multiple abnormalities. Artificial insemination was performed in three females; two eggs laid after artificial insemination had spermatozoa present on the perivitelline layer, suggesting the possible success of the insemination technique. Although no fertilization could be demonstrated, these preliminary results are promising, as they indicate that assisted reproduction might be a tool for species conservation in the Spix's macaw.


Asunto(s)
Conservación de los Recursos Naturales/métodos , Inseminación Artificial/veterinaria , Loros/fisiología , Análisis de Semen/veterinaria , Animales , Femenino , Masculino , Recuento de Espermatozoides , Motilidad Espermática , Espermatozoides/anomalías , Espermatozoides/citología
18.
Exp Neurol ; 371: 114610, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-37944880

RESUMEN

Hampering assessment of treatment outcomes in gene therapy and other clinical trials in patients with childhood dementia is the lack of an objective, non-invasive measure of neurodegeneration. Optical coherence tomography (OCT) is a widely available, rapid, non-invasive, and quantitative method for examining the integrity of the neuroretina. Profound brain and retinal dysfunction occur in patients and animal models of childhood dementia, including Sanfilippo syndrome and we recently revealed a correlation between the age of onset and rate of progression of retinal and brain degeneration in sulfamidase-deficient Sanfilippo mice. The aim of the current study was to use OCT to visualise the discrete changes in retinal structure that occur during disease progression. A progressive decline in retinal thickness was readily observable in Sanfilippo mice using OCT, with differences seen in affected animals from 10-weeks of age. OCT applied to i.v. AAV9-sulfamidase-treated Sanfilippo mice enabled visualisation of improved retinal anatomy in living animals, an outcome confirmed via histology. Importantly, brain disease lesions were also ameliorated in treated Sanfilippo mice. The findings highlight the sensitivity, ease of repetitive use and quantitative capacity of OCT for detection of discrete changes in retinal structure and their prevention with a therapeutic. Combined with the knowledge that retinal and brain degeneration are correlated in Sanfilippo syndrome, OCT provides a window to the brain in this and potentially other childhood dementias.


Asunto(s)
Demencia , Mucopolisacaridosis III , Humanos , Ratones , Animales , Mucopolisacaridosis III/diagnóstico por imagen , Mucopolisacaridosis III/genética , Mucopolisacaridosis III/terapia , Retina/diagnóstico por imagen , Retina/patología , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Terapia Genética , Demencia/patología , Modelos Animales de Enfermedad
19.
Mol Biol Cell ; 35(2): ar17, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38019605

RESUMEN

The RNA-binding protein Quaking (QKI) has widespread effects on mRNA regulation including alternative splicing, stability, translation, and localization of target mRNAs. Recently, QKI was found to be induced during epithelial-mesenchymal transition (EMT), where it promotes a mesenchymal alternative splicing signature that contributes to the mesenchymal phenotype. QKI is itself alternatively spliced to produce three major isoforms, QKI-5, QKI-6, and QKI-7. While QKI-5 is primarily localized to the nucleus where it controls mesenchymal splicing during EMT, the functions of the two predominantly cytoplasmic isoforms, QKI-6 and QKI-7, in this context remain uncharacterized. Here we used CRISPR-mediated depletion of QKI in a human mammary epithelial cell model of EMT and studied the effects of expressing the QKI isoforms in isolation and in combination. QKI-5 was required to induce mesenchymal morphology, while combined expression of QKI-5 with either QKI-6 or QKI-7 further enhanced mesenchymal morphology and cell migration. In addition, we found that QKI-6 and QKI-7 can partially localize to the nucleus and contribute to alternative splicing of QKI target genes. These findings indicate that the QKI isoforms function in a dynamic and cooperative manner to promote the mesenchymal phenotype.


Asunto(s)
Empalme Alternativo , Empalme del ARN , Humanos , Isoformas de Proteínas/metabolismo , Fenotipo , ARN Mensajero/genética , ARN Mensajero/metabolismo
20.
Cureus ; 15(11): e49473, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-38152773

RESUMEN

Pure white cell aplasia (PWCA) is a very rare hematological disorder with a nearly total absence of granulocytes and their precursor cells. While the disease is rarely diagnosed incidentally in otherwise asymptomatic individuals, most patients suffer from sometimes life-threatening infections. Due to its very low incidence, the precise pathomechanism of PWCA still needs to be elucidated. While most cases reported in the literature have been associated with an underlying thymic or autoimmune disease, some other factors including the intake of certain drugs such as antimicrobial agents or immune checkpoint inhibitors have been identified as potential triggers. Since PWCA is commonly refractory to treatment with granulocyte colony-stimulating factors (G-CSF), the main focus lies in identifying and eliminating the underlying trigger. Here, we report a unique case where the development of PWCA in a 56-year-old man with an upper respiratory tract infection has to be attributed to the long-term unprotected exposure to an industrial detergent containing high concentrations of the preservatives benzalkonium chloride (BAC) and 2-phenoxyethanol (2-PE). As a matter of fact, certain hematotoxic potential has been described in the literature for both BAC and 2-PE.

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