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To determine the role of the cystine/glutamate antiporter on retinal structure and function, retinas of C57Bl/6J wild-type and xCT knockout mice, lacking the xCT subunit of the cystine/glutamate antiporter were examined from 6 weeks to 12 months of age. Fundoscopy, optical coherence tomography (OCT), and whole mount retinal autofluorescence imaging were used to visualise age-related retinal spots. Glial fibrillary acidic protein (GFAP) immunolabelling was used to assess retinal stress. Retinal function was evaluated using full-field and focal electroretinograms. Examinations revealed retinal spots in both wild-type and xCT knockout mice with the number of spots greater at 9 months in the knockout compared to wild-type. OCT confirmed these discrete spots were located at the retinal pigment epithelium (RPE)-photoreceptor junction and did not label with drusen markers. Whole mount lambda scans of the 9 month xCT knockout retinas revealed that the photoreceptor autofluorescence matched the spots, suggesting these spots were retinal debris. GFAP labelling was increased in knockout retinas compared to wild-type indicative of retinal stress, and the discrete spots were associated with migration of microglia/macrophages to the RPE-retina intersection. OCT revealed that the superior retina was thinner at 9 months in knockout compared to wild-type mice due to changes to the outer nuclear and photoreceptor layers. While global retinal function was not affected by loss of xCT, focal changes in retinal function were detected in areas where spots were present. Tother these results suggest that the xCT KO mice exhibit features of accelerated ageing and suggests that this mouse model may be useful for studying the underlying cellular pathways in retinal ageing.

espanolLa integracion de varias posturas ideologicas de la comunidad academica en torno a los grandes problemas que afronta el planeta ha permitido establecer un complejo sistema de relaciones practicas y teoricas entre el hombre y la naturaleza, generando una fuerte conexion entre desarrollo sostenible y desarrollo humano, y confiriendo mayor prominencia al papel de los seres humanos, de acuerdo a sus poderes, libertades, y acciones para alcanzar y maximizar su bienestar individual y colectivo. En este sentido, el proposito de este capitulo es analizar la influencia del contexto humano en la conceptualizacion historica del desarrollo y su relacion con el bienestar humano y planetario durante los ultimos 50 anos. Intentamos comprobar que cuando se trata del desarrollo desde una perspectiva humana o desde la perspectiva de la sostenibilidad, se tiende hacia un mismo discurso que posibilita la convergencia y evolucion del concepto de desarrollo hacia una tendencia mucho menos utopica, con mayor alcance y aplicacion bajo el paradigma cientifico de sostenibilidad en terminos de bienestar humano. EnglishThe integration of the various ideological views by the academic community around the great problems facing the planet has allowed the establishment of a complex system of practical and theoretical relationships between man and nature, generating a strong connection between sustainable development and human development, and conferring greater prominence to the role of human beings, according to their powers, liberties and actions for achieving and maximizing their individual and collective well-being. In this regard, this chapter aims to analyze the influence of the human context in the historical conceptualization of development and its relation with human and planetary well-being over the past 50 years. We try to prove that when it comes to development from the human perspective or from the perspective of sustainability, it tends towards the same discourse that enables convergence and evolution of the concept of development into a much less utopian trend, with greater scope and application under the scientific paradigm of sustainability in terms of human welfare. portuguesA integracao de varias posturas ideologicas da comunidade academica em torno aos grandes problemas que afronta o planeta ha permitido estabelecer um complexo sistema de relacoes praticas e teoricas entre o homem e a natureza, gerando uma forte conexao entre desenvolvimento sustentavel e desenvolvimento humano, e conferindo maior prominencia ao papel dos seres humanos, de acordo aos seus poderes, liberdades, e acoes para alcancar e maximizar seu bem-estar individual e coletivo. Neste sentido, o proposito deste capitulo e analisar a influencia do contexto humano na conceptualizacao historica do desenvolvimento e sua relacao com o bem-estar humano e planetario durante os ultimos 50 anos. Tentamos comprovar que quando se trata do desenvolvimento desde uma perspectiva humana ou desde a perspectiva da sustentabilidade, se tende a um mesmo discurso que possibilita a convergencia e evolucao do conceito de desenvolvimento a uma tendencia muito menos utopica, com maior alcance e aplicacao sob o paradigma cientifico de sustentabilidade em termos de bem-estar humano.

Introduccion. El proposito del presente trabajo es el de investigar la probabilidad de supervivencia de las nuevas empresas creadas en el sector industrial de Medellin entre los anos 2000 y 2010. Asi mismo evidenciar algunos determinantes de los factores de exito en la consolidacion y aceptacion de las empresas en el mercado, en los periodos de tiempo inmediatamente posteriores a su gestacion. Objetivo. Calcular la tasa acumulada de supervivencia de las empresas pertenecientes al sector Industrial de la ciudad de Medellin creadas en el periodo comprendido entre los anos 2000 y 2010. Esto teniendo en cuenta el tamano, naturaleza juridica y sector industrial al que se circunscriben. Materiales y metodos. Para dar cuenta del objetivo se utilizo la funcion de supervivencia en un cierto periodo muestra el porcentaje de empresas vivas despues de que transcurran un numero determinado de periodos tras su aparicion. La funcion de riesgo muestra el porcentaje de empresas que cierra t periodos despues de su nacimiento. A su vez, la funcion de supervivencia recoge el porcentaje de empresas vivas t periodos despues del nacimiento. Resultados. El riesgo de desaparicion de una empresa disminuye conforme aumenta la antiguedad, adicionalmente, es menor en las empresas que nacen con un mayor tamano. La creacion de empresas es mayor entre las de menor tamano, pero presentan mayores tasas de mortalidad en los primeros anos de vida. La supervivencia de las nuevas empresas se encuentra positivamente relacionada con su tamano al nacer.

LANGUAGE NOTE | Document text in English; abstract also in Chinese. The implementation of Physical Education homework (PEHW) is new in Hong Kong. We examined the perception differences between a) parents and students; b) boys and girls towards PEHW in a primary school. Ninety students and 56 parents responded to a questionnaire after the completion of 1-week structured or unstructured compulsory PEHW daily which included aerobic, muscular and flexibility workout. T-test results showed that the students stated significantly lower levels of agreement than their parents regarding enjoyment of doing PEHW and the further organization of different PEHWs in school. No significant perception differences were reported between boys and girls towards the PEHW (p>0.05). Lack of time is the most frequently reason reported by the students and their parents as their intrapersonal barrier to participate in PEHW. Some incentives were suggested to promote the participation of PEHW. The present study suggests implementing PEHW with a reward scheme in Hong Kong. 小學四至六年級的學生完成一週強制性體育家課後，九十名學生和五十六名家長交回問卷回收率分別達94.2%和51.9%。T形檢驗結果顯示家長較學生贊成學校繼續組織及推行不同類型的體育家課。男女學童對體育家課的接受程度和各方面的反應是無明顯分別的。在開放式問題中，時間不足是最對學生參與體育家課的最大個人障礙。最後有多於三分之一的學生完成了餘下三週非強制性的體育家課。提議體育家課與獎勵計劃一起推行。

The integration of the various ideological views by the academic community around the great problems facing the planet has allowed the establishment of a complex system of practical and theoretical relationships between man and nature, generating a strong connection between sustainable development and human development, and conferring greater prominence to the role of human beings, according to their powers, liberties and actions for achieving and maximizing their individual and collective well-being. In this regard, this chapter aims to analyze the influence of the human context in the historical conceptualization of development and its relation with human and planetary well-being over the past 50 years. We try to prove that when it comes to development from the human perspective or from the perspective of sustainability, it tends towards the same discourse that enables convergence and evolution of the concept of development into a much less utopian trend, with greater scope and application under the scientific paradigm of sustainability in terms of human welfare. RESUMEN La integración de varias posturas ideológicas de la comunidad académica en torno a los grandes problemas que afronta el planeta ha permitido establecer un complejo sistema de relaciones prácticas y teóricas entre el hombre y la naturaleza, generando una fuerte conexión entre desarrollo sostenible y desarrollo humano, y confiriendo mayor prominencia al papel de los seres humanos, de acuerdo a sus poderes, libertades, y acciones para alcanzar y maximizar su bienestar individual y colectivo. En este sentido, el propósito de este capítulo es analizar la influencia del contexto humano en la conceptualización histórica del desarrollo y su relación con el bienestar humano y planetario durante los últimos 50 anos. Intentamos comprobar que cuando se trata del desarrollo desde una perspectiva humana o desde la perspectiva de la sostenibilidad, se tiende hacia un mismo discurso que posibilita la convergencia y evolución del concepto de desarrollo hacia una tendencia mucho menos utópica, con mayor alcance y aplicación bajo el paradigma científico de sostenibilidad en términos de bienestar humano. RESUMO A integração de várias posturas ideológicas da comunidade académica em torno aos grandes problemas que afronta o planeta há permitido estabelecer um complexo sistema de relações práticas e teóricas entre o homem e a natureza, gerando uma forte conexão entre desenvolvimento sustentável e desenvolvimento humano, e conferindo maior prominéncia ao papel dos seres humanos, de acordo aos seus poderes, liberdades, e ações para alcançar e maximizar seu bem-estar individual e coletivo. Neste sentido, o propósito deste capítulo é analisar a influência do contexto humano na conceptualização histórica do desenvolvimento e sua relação com o bem-estar humano e planetário durante os últimos 50 anos. Tentamos comprovar que quando se trata do desenvolvimento desde uma perspectiva humana ou desde a perspectiva da sustentabilidade, se tende a um mesmo discurso que possibilita a convergência e evolução do conceito de desenvolvimento a uma tendência muito menos utópica, com maior alcance e aplicação sob o paradigma científico de sustentabilidade em termos de bem-estar humano.

Introduction. The intention of this work is to invetigate the probability of survival of the new companies created in the Medellín Industrial sector between the years 2000 and 2010. Also to highlight some determinants of the factors of success in the consolidation and acceptance of companies in the Market, in the time lapses immediately following their gestation. Objective. Calculate the cumulative survival rate of companies belonging to the Industrial sector of the city of Medellín created in the period between 2000 and 2010. Considering the size, legal nature and industrial sector to which it is circumscribed. Materials and methods. To account for the objective was used the survival function in a certain period shows the percentage of companies alive after a certain number of periods after their appearance. The risk function shows the percentage of companies closing t periods of time after its birth. Results. The risk of disappearance of a company decreases as the antiquity increases, additionally, is smaller in companies that are born with a larger or big size. The creation of companies is greater among the smaller ones, but present higher mortality rates in the first years of life. The survival of new companies is positively related to their size at birth. Resumen Introducción. El propósito del presente trabajo es el de investigar la probabilidad de supervivencia de las nuevas empresas creadas en el sector industrial de Medellín entre los años 2000 y 2010. Así mismo evidenciar algunos determinantes de los factores de éxito en la consolidación y aceptación de las empresas en el mercado, en los periodos de tiempo inmediatamente posteriores a su gestación. Objetivo. Calcular la tasa acumulada de supervivencia de las empresas pertenecientes al sector Industrial de la ciudad de Medellín creadas en el período comprendido entre los años 2000 y 2010. Esto teniendo en cuenta el tamaño, naturaleza jurídica y sector industrial al que se circunscriben. Materiales y métodos. Para dar cuenta del objetivo se utilizó la función de supervivencia en un cierto período muestra el porcentaje de empresas vivas después de que transcurran un número determinado de períodos tras su aparición. La función de riesgo muestra el porcentaje de empresas que cierra t períodos después de su nacimiento. A su vez, la función de supervivencia recoge el porcentaje de empresas vivas t períodos después del nacimiento. Resultados. El riesgo de desaparición de una empresa disminuye conforme aumenta la antigüedad, adicionalmente, es menor en las empresas que nacen con un mayor tamaño. La creación de empresas es mayor entre las de menor tamaño, pero presentan mayores tasas de mortalidad en los primeros años de vida. La supervivencia de las nuevas empresas se encuentra positivamente relacionada con su tamaño al nacer. Resumo Introdução. O propósito do presente trabalho é o de investigar a probabilidade de supervivência das novas empresas criadas no setor industrial de Medellín entre os anos 2000 e 2010. Assim mesmo evidenciar alguns determinantes dos fatores de sucesso na consolidação e aceitação das empresas no mercado, nos períodos de tempo imediatamente posteriores à sua gestação. Objetivo. Calcular a taxa acumulada de supervivência das empresas pertencentes ao sector Industrial da cidade de Medellín criadas no período entre os anos 2000 e 2010. Isto tendo em conta o tamanho, natureza jurídica e setor industrial ao que se circunscrevem. Materiais e métodos. Para dar conta do objetivo se utilizou a função de supervivência num certo período de amostra a porcentagem de empresas vivas depois de que transcorram um número determinado de períodos após sua aparição. A função de risco mostra a porcentagem de empresas que fecha t períodos depois do seu nascimento. Por sua vez, a função de supervivência recolhe a porcentagem de empresas vivas t períodos depois do nascimento. Resultados. O risco de desaparição de uma empresa diminui conforme aumenta a antiguidade, adicionalmente, é menor nas empresas que nascem com um maior tamanho. A criação de empresas é maior entre as de menor tamanho, mas apresentam maiores taxas de mortalidade nos primeiros anos de vida. A supervivência das novas empresas se encontra positivamente relacionada com seu tamanho ao nascer.

The adeno-associated viruses (AAVs), which are being developed as gene delivery vectors, display differential cell surface glycan binding and subsequent tissue tropisms. For AAV serotype 1 (AAV1), the first viral vector approved as a gene therapy treatment, and its closely related AAV6, sialic acid (SIA) serves as their primary cellular surface receptor. Toward characterizing the SIA binding site(s), the structure of the AAV1-SIA complex was determined by X-ray crystallography to 3.0 Å. Density consistent with SIA was observed in a pocket located at the base of capsid protrusions surrounding icosahedral 3-fold axes. Site-directed mutagenesis substitution of the amino acids forming this pocket with structurally equivalent residues from AAV2, a heparan sulfate binding serotype, followed by cell binding and transduction assays, further mapped the critical residues conferring SIA binding to AAV1 and AAV6. For both viruses five of the six binding pocket residues mutated (N447S, V473D, N500E, T502S, and W503A) abolished SIA binding, whereas S472R increased binding. All six mutations abolished or decreased transduction by at least 50% in AAV1. Surprisingly, the T502S substitution did not affect transduction efficiency of wild-type AAV6. Furthermore, three of the AAV1 SIA binding site mutants—S472R, V473D, and N500E—escaped recognition by the anti-AAV1 capsid antibody ADK1a. These observations demonstrate that common key capsid surface residues dictate both virus binding and entry processes, as well as antigenic reactivity. This study identifies an important functional capsid surface “hot spot” dictating receptor attachment, transduction efficiency, and antigenicity which could prove useful for vector engineering. IMPORTANCE The adeno-associated virus (AAV) vector gene delivery system has shown promise in several clinical trials and an AAV1-based vector has been approved as the first gene therapy treatment. However, limitations still exist with respect to transduction efficiency and the detrimental effects of preexisting host antibodies. This study aimed to identify key capsid regions which can be engineered to overcome these limitations. A sialic glycan receptor recognition pocket was identified in AAV1 and its closely related AAV6, using X-ray crystallography. The site was confirmed by mutagenesis followed by cell binding and transduction assays. Significantly, residues controlling gene expression efficiency, as well as antibody escape variants, were also identified. This study thus provides, at the amino acid level, information for rational structural engineering of AAV vectors with improved therapeutic efficacy.

Wild-type TP53 exons 5-8 contain CpG dinucleotides that are prone to methylation-dependent mutation during carcinogenesis, but the regulatory effects of methylation affecting these CpG sites are unclear. To clarify this, we first assessed site-specific TP53 CpG methylation in normal and transformed cells. Both DNA damage and cell ageing were associated with site-specific CpG demethylation in exon 5 accompanied by induction of a truncated TP53 isoform regulated by an adjacent intronic promoter (P2). We then synthesized novel synonymous TP53 alleles with divergent CpG content but stable encodement of the wild-type polypeptide. Expression of CpG-enriched TP53 constructs selectively reduced production of the full-length transcript (P1), consistent with a causal relationship between intragenic demethylation and transcription. 450K methylation comparison of normal (TP53-wildtype) and cancerous (TP53-mutant) human cells and tissues revealed focal cancer-associated declines in CpG methylation near the P1 transcription start site, accompanied by rises near the alternate exon 5 start site. These data confirm that site-specific changes of intragenic TP53 CpG methylation are extrinsically inducible, and suggest that human cancer progression is mediated in part by dysregulation of damage-inducible intragenic CpG demethylation that alters TP53 P1/P2 isoform expression. © 2015 The Authors. Molecular Carcinogenesis Published by Wiley Periodicals, Inc.

Biocatalytic CO2sequestration to reduce greenhouse-gas emissions from industrial processes is an active area of research. Carbonic anhydrases (CAs) are attractive enzymes for this process. However, the most active CAs display limited thermal and pH stability, making them less than ideal. As a result, there is an ongoing effort to engineer and/or find a thermostable CA to fulfill these needs. Here, the kinetic and thermal characterization is presented of an α-CA recently discovered in the mesophilic hydrothermal vent-isolate extremophileThiomicrospira crunogenaXCL-2 (TcruCA), which has a significantly higher thermostability compared with human CA II (melting temperature of 71.9°Cversus59.5°C, respectively) but with a tenfold decrease in the catalytic efficiency. The X-ray crystallographic structure of the dimeric TcruCA shows that it has a highly conserved yet compact structure compared with other α-CAs. In addition, TcruCA contains an intramolecular disulfide bond that stabilizes the enzyme. These features are thought to contribute significantly to the thermostability and pH stability of the enzyme and may be exploited to engineer α-CAs for applications in industrial CO2sequestration.

Adeno-associated viruses (AAVs) are being development as gene delivery vectors and have shown promise in several clinical trials. And an AAV1-based vector has been approved by the European Commission for the treatment of lipoprotein lipase deficiency disease. However, limitations in tissue transduction specificity as well as neutralization by pre-existing antibodies remain are two major obstacles. To overcome these problems, it is important to characterize functional capsid regions that dictate virus binding to cellular receptors during infection and the potential overlap(s) of these regions with capsid antigenic epitopes. In this study, the sialic acid (SIA) binding site on AAV1 was determined by solving the structure of the AAV1-SIA complex using X-ray crystallography. Residues that form the SIA binding pocket are identical between AAV1 and AAV6; hence, structurally predicted SIA binding sites were mutated on both serotypes to confirm their role in the SIA interaction. Binding and transduction assays with these mutants in CHO cell lines Pro5, Lec2, Lec8, and Lec1, which display different terminal glycans, confirmed the structurally mapped binding pocket. Furthermore, native dot blot showed that several of the AAV1 SIA binding mutants can escape from antibody recognition. This finding is consistent with the overlap between the SIA binding site and the previously mapped AAV1 epitopes. Significantly, a glycan binding mutant with slightly reduced transduction ability is able to escape from antibody recognition. This study identifies an overlap between receptor recognition and antibody reactivity and provides amino acid level information for rational capsid engineering of AAV vectors for improved therapeutic efficacy.