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1.
Nature ; 580(7802): 232-234, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32269340

RESUMEN

Environmental change is rapidly accelerating, and many species will need to adapt to survive1. Ensuring that protected areas cover populations across a broad range of environmental conditions could safeguard the processes that lead to such adaptations1-3. However, international conservation policies have largely neglected these considerations when setting targets for the expansion of protected areas4. Here we show that-of 19,937 vertebrate species globally5-8-the representation of environmental conditions across their habitats in protected areas (hereafter, niche representation) is inadequate for 4,836 (93.1%) amphibian, 8,653 (89.5%) bird and 4,608 (90.9%) terrestrial mammal species. Expanding existing protected areas to cover these gaps would encompass 33.8% of the total land surface-exceeding the current target of 17% that has been adopted by governments. Priority locations for expanding the system of protected areas to improve niche representation occur in global biodiversity hotspots9, including Colombia, Papua New Guinea, South Africa and southwest China, as well as across most of the major land masses of the Earth. Conversely, we also show that planning for the expansion of protected areas without explicitly considering environmental conditions would marginally reduce the land area required to 30.7%, but that this would lead to inadequate niche representation for 7,798 (39.1%) species. As the governments of the world prepare to renegotiate global conservation targets, policymakers have the opportunity to help to maintain the adaptive potential of species by considering niche representation within protected areas1,2.


Asunto(s)
Conservación de los Recursos Naturales/legislación & jurisprudencia , Ecosistema , Política Ambiental/legislación & jurisprudencia , Internacionalidad , Animales , Biodiversidad , Gobierno Federal , Cooperación Internacional/legislación & jurisprudencia , Tamaño de la Muestra
2.
Ecol Appl ; 33(4): e2852, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36946332

RESUMEN

Climate change is already having profound effects on biodiversity, but climate change adaptation has yet to be fully incorporated into area-based management tools used to conserve biodiversity, such as protected areas. One main obstacle is the lack of consensus regarding how impacts of climate change can be included in spatial conservation plans. We propose a climate-smart framework that prioritizes the protection of climate refugia-areas of low climate exposure and high biodiversity retention-using climate metrics. We explore four aspects of climate-smart conservation planning: (1) climate model ensembles; (2) multiple emission scenarios; (3) climate metrics; and (4) approaches to identifying climate refugia. We illustrate this framework in the Western Pacific Ocean, but it is equally applicable to terrestrial systems. We found that all aspects of climate-smart conservation planning considered affected the configuration of spatial plans. The choice of climate metrics and approaches to identifying refugia have large effects in the resulting climate-smart spatial plans, whereas the choice of climate models and emission scenarios have smaller effects. As the configuration of spatial plans depended on climate metrics used, a spatial plan based on a single measure of climate change (e.g., warming) will not necessarily be robust against other measures of climate change (e.g., ocean acidification). We therefore recommend using climate metrics most relevant for the biodiversity and region considered based on a single or multiple climate drivers. To include the uncertainty associated with different climate futures, we recommend using multiple climate models (i.e., an ensemble) and emission scenarios. Finally, we show that the approaches we used to identify climate refugia feature trade-offs between: (1) the degree to which they are climate-smart, and (2) their efficiency in meeting conservation targets. Hence, the choice of approach will depend on the relative value that stakeholders place on climate adaptation. By using this framework, protected areas can be designed with improved longevity and thus safeguard biodiversity against current and future climate change. We hope that the proposed climate-smart framework helps transition conservation planning toward climate-smart approaches.


Asunto(s)
Conservación de los Recursos Naturales , Agua de Mar , Conservación de los Recursos Naturales/métodos , Concentración de Iones de Hidrógeno , Biodiversidad , Incertidumbre , Cambio Climático , Ecosistema
3.
Conserv Biol ; 37(3): e14048, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36661081

RESUMEN

Protected areas are a key instrument for conservation. Despite this, they are vulnerable to risks associated with weak governance, land-use intensification, and climate change. We used a novel hierarchical optimization approach to identify priority areas for expanding the global protected area system that explicitly accounted for such risks while maximizing protection of all known terrestrial vertebrate species. To incorporate risk categories, we built on the minimum set problem, where the objective is to reach species distribution protection targets while accounting for 1 constraint, such as land cost or area. We expanded this approach to include multiple objectives accounting for risk in the problem formulation by treating each risk layer as a separate objective in the problem formulation. Reducing exposure to these risks required expanding the area of the global protected area system by 1.6% while still meeting conservation targets. Incorporating risks from weak governance drove the greatest changes in spatial priorities for protection, and incorporating risks from climate change required the largest increase (2.52%) in global protected area. Conserving wide-ranging species required countries with relatively strong governance to protect more land when they bordered nations with comparatively weak governance. Our results underscore the need for cross-jurisdictional coordination and demonstrate how risk can be efficiently incorporated into conservation planning. Planeación de las áreas protegidas para conservar la biodiversidad en un futuro incierto.


Aunque las áreas protegidas son un instrumento clave para la conservación, no dejan de ser vulnerables a los riesgos asociados a una gestión pobre, la intensificación del uso de suelo y al cambio climático. Usamos una estrategia novedosa de optimización jerárquica para identificar las áreas prioritarias para la expansión del sistema global de áreas protegidas. La estrategia consideró de manera explícita los riesgos mencionados y también maximizó la protección de todas las especies conocidas de vertebrados terrestres. Para incorporar a las categorías de riesgo partimos del mínimo problema establecido, en donde el objetivo es lograr los objetivos de protección de la distribución de especies mientras se considera sólo una restricción, como el costo o área del suelo. Expandimos esta estrategia para que incluyera varios objetivos que consideraran el riesgo desde la formulación del problema mediante el manejo de cada nivel de riesgo como un objetivo aparte durante la formulación del problema. La reducción de la exposición a estos riesgos requirió que se expandiera el área total del sistema global de áreas protegidas en un 1.6% y así todavía cumplir con los objetivos de conservación. La incorporación de riesgos a partir de una gestión pobre fue el principal impulsor de cambios en las prioridades espaciales para la protección, mientras que la incorporación de riesgos a partir del cambio climático requirió el mayor incremento (2.52%) del área protegida a nivel mundial. La conservación de especies con distribución amplia requirió que los países con una gestión relativamente fuerte protegieran más suelo al tener fronteras con países con una gestión pobre en comparación son la suya. Nuestros resultados destacan la necesidad de una coordinación entre jurisdicciones y demuestran cómo puede incorporarse el riesgo de manera exitosa a la planeación de la conservación.


Asunto(s)
Biodiversidad , Conservación de los Recursos Naturales , Cambio Climático , Incertidumbre , Ecosistema
4.
Biotechnol Bioeng ; 119(1): 162-175, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34655229

RESUMEN

Recent advances in cell-free protein synthesis have enabled the folding and assembly of full-length antibodies at high titers with extracts from prokaryotic cells. Coupled with the facile engineering of the Escherichia coli translation machinery, E. coli based in vitro protein synthesis reactions have emerged as a leading source of IgG molecules with nonnatural amino acids incorporated at specific locations for producing homogeneous antibody-drug conjugates (ADCs). While this has been demonstrated with extract produced in batch fermentation mode, continuous extract fermentation would facilitate supplying material for large-scale manufacturing of protein therapeutics. To accomplish this, the IgG-folding chaperones DsbC and FkpA, and orthogonal tRNA for nonnatural amino acid production were integrated onto the chromosome with high strength constitutive promoters. This enabled co-expression of all three factors at a consistently high level in the extract strain for the duration of a 5-day continuous fermentation. Cell-free protein synthesis reactions with extract produced from cells grown continuously yielded titers of IgG containing nonnatural amino acids above those from extract produced in batch fermentations. In addition, the quality of the synthesized IgGs and the potency of ADC produced with continuously fermented extract were indistinguishable from those produced with the batch extract. These experiments demonstrate that continuous fermentation of E. coli to produce extract for cell-free protein synthesis is feasible and helps unlock the potential for cell-free protein synthesis as a platform for biopharmaceutical production.


Asunto(s)
Sistema Libre de Células/microbiología , Escherichia coli , Inmunoconjugados/metabolismo , Ingeniería Metabólica/métodos , Reactores Biológicos/microbiología , Escherichia coli/genética , Escherichia coli/metabolismo , Fermentación
5.
Conserv Biol ; 35(2): 634-642, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-32761662

RESUMEN

Protected-area systems should conserve intraspecific genetic diversity. Because genetic data require resources to obtain, several approaches have been proposed for generating plans for protected-area systems (prioritizations) when genetic data are not available. Yet such surrogate-based approaches remain poorly tested. We evaluated the effectiveness of potential surrogate-based approaches based on microsatellite genetic data collected across the Iberian Peninsula for 7 amphibian and 3 reptilian species. Long-term environmental suitability did not effectively represent sites containing high genetic diversity (allelic richness). Prioritizations based on long-term environmental suitability had similar performance to random prioritizations. Geographic distances and resistance distances based on contemporary environmental suitability were not always effective surrogates for identification of combinations of sites that contain individuals with different genetic compositions. Our results demonstrate that population genetic data based on commonly used neutral markers can inform prioritizations, and we could not find an adequate substitute. Conservation planners need to weigh the potential benefits of genetic data against their acquisition costs.


Evaluación de los Sustitutos de la Diversidad Genética para la Planeación de la Conservación Resumen Los sistemas de áreas protegidas deberían conservar la diversidad genética intraespecífica. Ya que para obtener datos genéticos se requieren recursos, se han propuesto distintas estrategias para generar los planes para los sistemas de áreas protegidas (priorizaciones) cuando los datos genéticos no están disponibles. A pesar de lo anterior, dichas estrategias basadas en sustitutos han sido poco evaluadas. Evaluamos la efectividad del potencial de las estrategias basadas en sustitutos cuya base son los datos genéticos de microsatélites obtenidos en toda la Península Ibérica y correspondientes a siete especies de anfibios y a tres de reptiles. La idoneidad ambiental a largo plazo no representó efectivamente los sitios que contienen una diversidad genética alta (riqueza de alelos). Las priorizaciones basadas en la idoneidad ambiental a largo plazo tuvieron un desempeño similar a las priorizaciones aleatorias. Las distancias geográficas y las distancias de resistencia basadas en la idoneidad ambiental contemporánea no siempre fueron sustitutos efectivos para la identificación de las combinaciones de sitios que contienen individuos con composiciones genéticas diferentes. Nuestros resultados demuestran que los datos genéticos de una población basados en marcadores neutrales de uso común pueden informar a las priorizaciones y que no pudimos encontrar un sustituto adecuado. Los planificadores de la conservación necesitan sopesar los beneficios potenciales de los datos genéticos contra sus costos de adquisición.


Asunto(s)
Biodiversidad , Conservación de los Recursos Naturales , Ecosistema , Europa (Continente) , Variación Genética
6.
Proc Natl Acad Sci U S A ; 114(48): 12755-12760, 2017 11 28.
Artículo en Inglés | MEDLINE | ID: mdl-29087942

RESUMEN

Protected areas buffer species from anthropogenic threats and provide places for the processes that generate and maintain biodiversity to continue. However, genetic variation, the raw material for evolution, is difficult to capture in conservation planning, not least because genetic data require considerable resources to obtain and analyze. Here we show that freely available environmental and geographic distance variables can be highly effective surrogates in conservation planning for representing adaptive and neutral intraspecific genetic variation. We obtained occurrence and genetic data from the IntraBioDiv project for 27 plant species collected over the European Alps using a gridded sampling scheme. For each species, we identified loci that were potentially under selection using outlier loci methods, and mapped their main gradients of adaptive and neutral genetic variation across the grid cells. We then used the cells as planning units to prioritize protected area acquisitions. First, we verified that the spatial patterns of environmental and geographic variation were correlated, respectively, with adaptive and neutral genetic variation. Second, we showed that these surrogates can predict the proportion of genetic variation secured in randomly generated solutions. Finally, we discovered that solutions based only on surrogate information secured substantial amounts of adaptive and neutral genetic variation. Our work paves the way for widespread integration of surrogates for genetic variation into conservation planning.


Asunto(s)
Conservación de los Recursos Naturales/métodos , Variación Genética , Modelos Genéticos , Plantas/genética , Adaptación Biológica/genética , Altitud , Biodiversidad , Europa (Continente) , Plantas/clasificación , Refugio de Fauna
7.
Mol Pharm ; 15(5): 2054-2059, 2018 05 07.
Artículo en Inglés | MEDLINE | ID: mdl-29569925

RESUMEN

Antibody-drug conjugates (ADCs) are antigen-targeted therapeutics that employ antibodies to deliver potent, cytotoxic effectors to cells with potentially high specificity. While promising clinical results have been achieved, significant pitfalls remain including internalization of ADCs in nontargeted cells expressing target antigen, which can limit therapeutic windows. Novel ADC linkers that are cleaved selectively in cancer cells but not in normal cells could minimize collateral damage caused by ADC uptake in nontargeted tissues. Here, we describe a prototypical ADC linker based on an Fe(II)-reactive 1,2,4-trioxolane scaffold (TRX) that by itself has demonstrated tumor-selective activity in preclinical cancer models. We prepared TRX-linked ADCs by site-selective conjugation to two sites in trastuzumab and compared their activity in Her2 positive and negative cells to ADC controls based on established linker chemistry. Our results confirm that the TRX moiety efficiently releases its payload following ADC uptake, affording picomolar potencies in antigen-positive cells. We also identified a destabilizing interaction between these initial TRX linkers and nearby antibody residues and suggest an approach to improve upon these prototypical designs.


Asunto(s)
Anticuerpos Monoclonales/química , Antineoplásicos/química , Inmunoconjugados/química , Hierro/química , Animales , Antígenos/química , Línea Celular Tumoral , Mamíferos , Receptor ErbB-2/metabolismo , Trastuzumab/química
8.
Gastroenterology ; 151(1): 140-51, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-27003604

RESUMEN

BACKGROUND & AIMS: Small intestinal neuroendocrine tumors (SI-NETs) are serotonin-secreting well-differentiated neuroendocrine tumors believed to originate from enterochromaffin (EC) cells. Intestinal stem cell (ISC) are believed to contribute to the formation of SI-NETs, although little is known about tumor formation or development. We investigated the relationship between EC cells, ISCs, and SI-NETs. METHODS: We analyzed jejuno-ileal tissue specimens from 14 patients with familial SI-NETs enrolled in the Natural History of Familial Carcinoid Tumor study at the National Institutes of Health from January 2009 to December 2014. Frozen and paraffin-embedded tumor tissues of different stages and isolated crypts were analyzed by in situ hybridization and immunohistochemistry. Tumor clonality was assessed by analyses of mitochondrial DNA. RESULTS: We identified multifocal aberrant crypt-containing endocrine cell clusters (ACECs) that contain crypt EC cell microtumors in patients with familial SI-NETs. RNA in situ hybridization revealed expression of the EC cell and reserve stem cell genes TPH1, BMI1, HOPX, and LGR5(low), in the ACECs and more advanced extraepithelial tumor nests. This expression pattern resembled that of reserve EC cells that express reserve ISC genes; most reside at the +4 position in normal crypts. The presence of multifocal ACECs from separate tumors and in the macroscopic tumor-free mucosa indicated widespread, independent, multifocal tumorigenesis. Analyses of mitochondrial DNA confirmed the independent origin of the ACECs. CONCLUSIONS: Familial SI-NETs originate from a subset of EC cells (reserve EC cells that express reserve ISC genes) via multifocal and polyclonal processes. Increasing our understanding of the role of these reserve EC cells in the genesis of multifocal SI-NETs could improve diagnostic and therapeutic strategies for this otherwise intractable disease.


Asunto(s)
Carcinogénesis/genética , Neoplasias del Íleon/genética , Neoplasias del Yeyuno/genética , Familia de Multigenes/genética , Tumores Neuroendocrinos/genética , Células Enterocromafines/metabolismo , Proteínas de Homeodominio/genética , Humanos , Hibridación in Situ , Intestino Delgado/citología , Complejo Represivo Polycomb 1/genética , Receptores Acoplados a Proteínas G/genética , Células Madre/metabolismo , Triptófano Hidroxilasa/genética , Proteínas Supresoras de Tumor/genética
9.
Mol Ecol ; 25(2): 470-86, 2016 01.
Artículo en Inglés | MEDLINE | ID: mdl-26588177

RESUMEN

Landscape genetics lacks explicit methods for dealing with the uncertainty in landscape resistance estimation, which is particularly problematic when sample sizes of individuals are small. Unless uncertainty can be quantified, valuable but small data sets may be rendered unusable for conservation purposes. We offer a method to quantify uncertainty in landscape resistance estimates using multimodel inference as an improvement over single model-based inference. We illustrate the approach empirically using co-occurring, woodland-preferring Australian marsupials within a common study area: two arboreal gliders (Petaurus breviceps, and Petaurus norfolcensis) and one ground-dwelling antechinus (Antechinus flavipes). First, we use maximum-likelihood and a bootstrap procedure to identify the best-supported isolation-by-resistance model out of 56 models defined by linear and non-linear resistance functions. We then quantify uncertainty in resistance estimates by examining parameter selection probabilities from the bootstrapped data. The selection probabilities provide estimates of uncertainty in the parameters that drive the relationships between landscape features and resistance. We then validate our method for quantifying uncertainty using simulated genetic and landscape data showing that for most parameter combinations it provides sensible estimates of uncertainty. We conclude that small data sets can be informative in landscape genetic analyses provided uncertainty can be explicitly quantified. Being explicit about uncertainty in landscape genetic models will make results more interpretable and useful for conservation decision-making, where dealing with uncertainty is critical.


Asunto(s)
Genética de Población , Marsupiales/genética , Modelos Genéticos , Animales , Variación Genética , Técnicas de Genotipaje , Funciones de Verosimilitud , Repeticiones de Microsatélite , Modelos Estadísticos , Queensland , Tamaño de la Muestra , Análisis de Secuencia de ADN , Incertidumbre
11.
Blood ; 121(10): 1795-804, 2013 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-23305738

RESUMEN

Hodgkin/Reed-Sternberg (HRS) cells of classical Hodgkin lymphoma (cHL) rarely express T-cell-associated antigens (TCA), but the clinical significance of this finding is uncertain. Fifty cHLs expressing any TCA on the HRS cells (TCA-cHL) were identified in two cohorts (National Cancer Institute, n = 38; Basel, n = 12). Diagnostic pathology data were examined in all cases with additional T-cell receptor γ rearrangements (TRG@) polymerase chain reaction (PCR) in a subset of cases. The outcome data were compared with a cohort of cHLs negative for TCA (n = 272). Primary end points examined were event-free survival (EFS) and overall survival (OS). The median age in the TCA-cHL group was 40 years (range, 10-85 years). Seventy percent presented in low stage (stage I/II) at presentation with nodular sclerosis (NS) histology predominating in 80% of cases. Among the TCA, CD4 and CD2 were most commonly expressed, seen in 80.4% and 77.4% of cases, respectively. TRG@ PCR was negative for clonal rearrangements in 29 of 31 cases. During a median follow up of 113 months, TCA expression predicted shorter OS (adjusted hazard ratio [HRadj] = 3.32 [95% confidence interval (CI): 1.61, 6.84]; P = .001) and EFS (HRadj = 2.55 [95% CI: 1.45, 4.49]; P = .001). TCA-cHL often display NS histology, lack T-cell genotype, and are independently associated with significantly shorter OS and EFS compared with TCA-negative cHLs.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Enfermedad de Hodgkin/mortalidad , Recurrencia Local de Neoplasia/mortalidad , Receptores de Antígenos de Linfocitos T/metabolismo , Células de Reed-Sternberg/metabolismo , Adolescente , Adulto , Anciano , Biomarcadores de Tumor/genética , Estudios de Casos y Controles , Niño , Estudios de Cohortes , ADN de Neoplasias/genética , Femenino , Estudios de Seguimiento , Reordenamiento Génico , Genes de las Cadenas Pesadas de las Inmunoglobulinas/genética , Enfermedad de Hodgkin/genética , Enfermedad de Hodgkin/metabolismo , Humanos , Técnicas para Inmunoenzimas , Hibridación in Situ , Captura por Microdisección con Láser , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/genética , Recurrencia Local de Neoplasia/metabolismo , Estadificación de Neoplasias , Reacción en Cadena de la Polimerasa , Pronóstico , Receptores de Antígenos de Linfocitos T/genética , Tasa de Supervivencia , Adulto Joven
12.
Pediatr Res ; 77(3): 406-15, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25521919

RESUMEN

BACKGROUND: In juvenile mammals, the epiphyses of long bones grow by chondrogenesis within the articular cartilage. A better understanding of the molecular mechanisms that regulate the growth of articular cartilage may give insight into the antecedents of joint disease, such as osteoarthritis. METHODS: We used laser capture microdissection to isolate chondrocytes from the superficial, middle, and deep zones of growing tibial articular cartilage in the 1-wk-old mouse and then investigated expression patterns by microarray. To identify molecular markers for each zone of the growing articular cartilage, we found genes showing zone-specific expression and confirmed by real-time PCR and in situ hybridization. RESULTS: Bioinformatic analyses implicated ephrin receptor signaling, Wnt signaling, and bone morphogenetic protein signaling in the spatial regulation of chondrocyte differentiation during growth. Molecular markers were identified for superficial (e.g., Cilp, Prg4), middle (Cxcl14, Tnn), and deep zones (Sfrp5, Frzb). Comparison between juvenile articular and growth plate cartilage revealed that the superficial-to-deep zone transition showed similarity with the hypertrophic-to-resting zone transition. CONCLUSION: Laser capture microdissection combined with microarray analysis identified novel signaling pathways that are spatially regulated in growing mouse articular cartilage and revealed similarities between the molecular architecture of the growing articular cartilage and that of growth plate cartilage.


Asunto(s)
Cartílago Articular/crecimiento & desarrollo , Condrogénesis/fisiología , Regulación del Desarrollo de la Expresión Génica/fisiología , Transducción de Señal/fisiología , Animales , Proteínas Morfogenéticas Óseas/metabolismo , Cartílago Articular/metabolismo , Diferenciación Celular/fisiología , Biología Computacional , Perfilación de la Expresión Génica , Hibridación in Situ , Captura por Microdisección con Láser , Ratones , Análisis por Micromatrices , Reacción en Cadena en Tiempo Real de la Polimerasa , Receptores de la Familia Eph/metabolismo , Proteínas Wnt/metabolismo
13.
Conserv Biol ; 29(6): 1626-35, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26171646

RESUMEN

Decisions need to be made about which biodiversity management actions are undertaken to mitigate threats and about where these actions are implemented. However, management actions can interact; that is, the cost, benefit, and feasibility of one action can change when another action is undertaken. There is little guidance on how to explicitly and efficiently prioritize management for multiple threats, including deciding where to act. Integrated management could focus on one management action to abate a dominant threat or on a strategy comprising multiple actions to abate multiple threats. Furthermore management could be undertaken at sites that are in close proximity to reduce costs. We used cost-effectiveness analysis to prioritize investments in fire management, controlling invasive predators, and reducing grazing pressure in a bio-diverse region of southeastern Queensland, Australia. We compared outcomes of 5 management approaches based on different assumptions about interactions and quantified how investment needed, benefits expected, and the locations prioritized for implementation differed when interactions were taken into account. Managing for interactions altered decisions about where to invest and in which actions to invest and had the potential to deliver increased investment efficiency. Differences in high priority locations and actions were greatest between the approaches when we made different assumptions about how management actions deliver benefits through threat abatement: either all threats must be managed to conserve species or only one management action may be required. Threatened species management that does not consider interactions between actions may result in misplaced investments or misguided expectations of the effort required to mitigate threats to species.


Asunto(s)
Crianza de Animales Domésticos , Conservación de los Recursos Naturales/métodos , Análisis Costo-Beneficio , Incendios , Especies Introducidas , Biodiversidad , Conservación de los Recursos Naturales/economía , Modelos Teóricos , Queensland
14.
J Transl Med ; 12: 230, 2014 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-25141867

RESUMEN

BACKGROUND: The molecular mechanisms whereby hepatitis B virus (HBV) induces hepatocellular carcinoma (HCC) remain elusive. We used genomic and molecular techniques to investigate host-virus interactions by studying multiple areas of the same liver from patients with HCC. METHODS: We compared the gene signature of whole liver tissue (WLT) versus laser capture-microdissected (LCM) hepatocytes along with the intrahepatic expression of HBV. Gene expression profiling was performed on up to 17 WLT specimens obtained at various distances from the tumor center from individual livers of 11 patients with HCC and on selected LCM samples. HBV markers in liver and serum were determined by real-time polymerase chain reaction (PCR) and confocal immunofluorescence. RESULTS: Analysis of 5 areas of the liver showed a sharp change in gene expression between the immediate perilesional area and tumor periphery that correlated with a significant decrease in the intrahepatic expression of HB surface antigen (HBsAg). The tumor was characterized by a large preponderance of down-regulated genes, mostly involved in the metabolism of lipids and fatty acids, glucose, amino acids and drugs, with down-regulation of pathways involved in the activation of PXR/RXR and PPARα/RXRα nuclear receptors, comprising PGC-1α and FOXO1, two key regulators critically involved not only in the metabolic functions of the liver but also in the life cycle of HBV, acting as essential transcription factors for viral gene expression. These findings were confirmed by gene expression of microdissected hepatocytes. Moreover, LCM of malignant hepatocytes also revealed up-regulation of unique genes associated with cancer and signaling pathways, including two novel HCC-associated cancer testis antigen genes, NUF2 and TTK. CONCLUSIONS: Integrated gene expression profiling of whole liver tissue with that of microdissected hepatocytes demonstrated that HBV-associated HCC is characterized by a metabolism switch-off and by a significant reduction in HBsAg. LCM proved to be a critical tool to validate gene signatures associated with HCC and to identify genes that may play a role in hepatocarcinogenesis, opening new perspectives for the discovery of novel diagnostic markers and therapeutic targets.


Asunto(s)
Carcinoma Hepatocelular/genética , Genes Virales , Virus de la Hepatitis B/genética , Hepatitis B/complicaciones , Hepatocitos/metabolismo , Neoplasias Hepáticas/genética , Hígado/metabolismo , Anciano , Carcinoma Hepatocelular/virología , Femenino , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Regulación Viral de la Expresión Génica , Hepatitis B/genética , Virus de la Hepatitis B/patogenicidad , Hepatocitos/virología , Interacciones Huésped-Patógeno/genética , Humanos , Captura por Microdisección con Láser , Hígado/virología , Neoplasias Hepáticas/virología , Masculino , Persona de Mediana Edad , Transcriptoma
15.
Am J Pathol ; 183(4): 1329-38, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24070418

RESUMEN

The olfactomedin 4 (OLFM4) gene is located on chromosome 13q14.3, which frequently is deleted in human prostate cancer. However, direct genetic evidence of OLFM4 gene alteration in human prostate cancer has not yet been obtained. In this study, we investigated the genetics, protein expression, and functions of the OLFM4 gene in human prostate cancer. We found overall 25% deletions within the OLFM4 gene in cancerous epithelial cells compared with adjacent normal epithelial cells that were microdissected from 31 prostate cancer specimens using laser-capture microdissection and genomic DNA sequencing. We found 28% to 45% hemizygous and 15% to 57% homozygous deletions of the OLFM4 gene via fluorescence in situ hybridization analysis from 44 different prostate cancer patient samples. Moreover, homozygous deletion of the OLFM4 gene significantly correlated with advanced prostate cancer. By using immunohistochemical analysis of 162 prostate cancer tissue array samples representing a range of Gleason scores, we found that OLFM4 protein expression correlated inversely with advanced prostate cancer, consistent with the genetic results. We also showed that a truncated mutant of OLFM4 that lacks the olfactomedin domain eliminated suppression of PC-3 prostate cancer cell growth. Together, our findings indicate that OLFM4 is a novel candidate tumor-suppressor gene for chromosome 13q and may shed new light on strategies that could be used for the diagnosis, prognosis, and treatment of prostate cancer patients.


Asunto(s)
Progresión de la Enfermedad , Eliminación de Gen , Factor Estimulante de Colonias de Granulocitos/genética , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/patología , Autofagia/genética , Secuencia de Bases , Catepsina D/metabolismo , Línea Celular Tumoral , Proliferación Celular , Regulación Neoplásica de la Expresión Génica , Genoma Humano/genética , Factor Estimulante de Colonias de Granulocitos/química , Factor Estimulante de Colonias de Granulocitos/metabolismo , Homocigoto , Humanos , Hibridación Fluorescente in Situ , Captura por Microdisección con Láser , Masculino , Datos de Secuencia Molecular , Proteínas Mutantes/metabolismo , Estadificación de Neoplasias , Polimorfismo de Nucleótido Simple/genética , Neoplasias de la Próstata/enzimología , Estructura Terciaria de Proteína , Análisis de Matrices Tisulares
16.
Nat Commun ; 15(1): 261, 2024 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-38199986

RESUMEN

Meeting global commitments to conservation, climate, and sustainable development requires consideration of synergies and tradeoffs among targets. We evaluate the spatial congruence of ecosystems providing globally high levels of nature's contributions to people, biodiversity, and areas with high development potential across several sectors. We find that conserving approximately half of global land area through protection or sustainable management could provide 90% of the current levels of ten of nature's contributions to people and meet minimum representation targets for 26,709 terrestrial vertebrate species. This finding supports recent commitments by national governments under the Global Biodiversity Framework to conserve at least 30% of global lands and waters, and proposals to conserve half of the Earth. More than one-third of areas required for conserving nature's contributions to people and species are also highly suitable for agriculture, renewable energy, oil and gas, mining, or urban expansion. This indicates potential conflicts among conservation, climate and development goals.


Asunto(s)
Ecosistema , Planetas , Humanos , Biodiversidad , Agricultura , Clima
17.
MAbs ; 16(1): 2316872, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38381460

RESUMEN

Therapeutic bioconjugates are emerging as an essential tool to combat human disease. Site-specific conjugation technologies are widely recognized as the optimal approach for producing homogeneous drug products. Non-natural amino acid (nnAA) incorporation allows the introduction of bioconjugation handles at genetically defined locations. Escherichia coli (E. coli) is a facile host for therapeutic nnAA protein synthesis because it can stably replicate plasmids encoding genes for product and nnAA incorporation. Here, we demonstrate that by engineering E. coli to incorporate high levels of nnAAs, it is feasible to produce nnAA-containing antibody fragments and full-length immunoglobulin Gs (IgGs) in the cytoplasm of E. coli. Using high-density fermentation, it was possible to produce both of these types of molecules with site-specifically incorporated nnAAs at titers > 1 g/L. We anticipate this strategy will help simplify the production and manufacture of promising antibody therapeutics.


Asunto(s)
Aminoácidos , Escherichia coli , Humanos , Aminoácidos/genética , Escherichia coli/genética , Fragmentos de Inmunoglobulinas , Anticuerpos/genética
18.
Toxicol Pathol ; 41(7): 970-83, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23788571

RESUMEN

Conjugation of therapeutic proteins with high molecular weight polyethylene glycols (HMW PEGs) is used to extend the half-life of biologics. To evaluate the effects of HMW PEGs in animals, we used an immunohistochemical procedure to study the tissue distribution and toxicity of unconjugated HMW PEGs in rats given 100 mg/kg (10K)PEG, (20K)PEG, or (40K)PEG intravenously. Both the PEG cellular distribution and the histology were different between groups. In (10K)PEG and (20K)PEG groups, PEG immunoreactivity was most prominent in the renal tubule epithelium and in alveolar macrophages and hepatic Kupffer cells and cellular vacuolation was absent. In contrast, rats given (40K)PEG had strong PEG immunoreactivity in splenic subcapsular red pulp macrophages, renal interstitial macrophages, and choroid plexus epithelial cells that was frequently associated with cytoplasmic vacuolation. While the vacuolation appeared to be an adaptive response, there was focal renal tubular epithelial degeneration associated with strong PEG immunoreactivity in one rat given (40K)PEG. These data indicate that both the tissue distribution and the vacuolation observed with unconjugated HMW PEGs are markedly influenced by the molecular weight of the PEG and that when vacuolation is observed it is likely an adaptive change that is associated with PEG cytoplasmic immunoreactivity.


Asunto(s)
Polietilenglicoles/farmacocinética , Vacuolas/efectos de los fármacos , Vacuolas/patología , Animales , Plexo Coroideo/efectos de los fármacos , Plexo Coroideo/metabolismo , Plexo Coroideo/patología , Inmunohistoquímica , Riñón/efectos de los fármacos , Riñón/metabolismo , Riñón/patología , Pulmón/citología , Pulmón/efectos de los fármacos , Pulmón/metabolismo , Pulmón/patología , Macaca fascicularis , Masculino , Peso Molecular , Polietilenglicoles/química , Polietilenglicoles/toxicidad , Ratas , Ratas Sprague-Dawley , Vacuolas/metabolismo
19.
J Anesth ; 27(5): 705-11, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23558470

RESUMEN

PURPOSE: Hereditary hemorrhagic telangiectasia is a rare autosomal dominant disease characterized by capillary malformation leading to multisite cutaneomucosal telangiectasias and multiorgan arteriovenous malformations, which can present challenges to anesthetic care. The primary aim of this report is to present a large cohort of patients with hereditary hemorrhagic telangiectasia undergoing general anesthesia at our institution in regard to comorbid conditions and complications of surgical and anesthetic management. METHODS: A computerized search from January 1, 2002 through December 31, 2011 of the Mayo Clinic medical records database was performed for patients with hereditary hemorrhagic telangiectasia who underwent general anesthesia. Medical records were reviewed. Eligibility criteria included patients with definite or suspected hereditary hemorrhagic telangiectasia based on the Curacao diagnostic criteria who underwent general anesthesia during the study period. RESULTS: We identified 74 patients with hereditary hemorrhagic telangiectasia who underwent 163 surgeries. The majority had pulmonary arteriovenous malformations (56.7%) and iron deficiency anemia (64.7%), and high levels of disease burden with a median American Society of Anesthesiologist Physical Status score of 3. Most surgeries were related to treating conditions associated with hereditary hemorrhagic telangiectasia, with the majority being procedures to the nasal mucosa for recurrent epistaxis (47.2%). A sizeable proportion of procedures to the nasal mucosa required transfusion of blood (12/77). One case of epistaxis required 11 units of blood until it was successfully controlled. Another notable complication included migration of a coil to pulmonary arteriovenous malformations into the cerebral circulation. CONCLUSION: Surgical patients with hereditary hemorrhagic telangiectasia often present with multiorgan involvement. The anesthesia provider needs to be aware of the high prevalence of pulmonary arteriovenous malformations, which may be asymptomatic but can lead to embolic complications. Hemorrhage from epistaxis can be severe, and relatively focal procedures to the nasal mucosa can require blood transfusions.


Asunto(s)
Anestesia General/métodos , Telangiectasia Hemorrágica Hereditaria/fisiopatología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Anestesia General/efectos adversos , Malformaciones Arteriovenosas/etiología , Niño , Preescolar , Epistaxis/etiología , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Mucosa Nasal/patología , Procedimientos Quirúrgicos Operativos/métodos , Telangiectasia Hemorrágica Hereditaria/patología , Adulto Joven
20.
Trends Ecol Evol ; 38(2): 143-155, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36210287

RESUMEN

Integrative and proactive conservation approaches are critical to the long-term persistence of biodiversity. Molecular data can provide important information on evolutionary processes necessary for conserving multiple levels of biodiversity (genes, populations, species, and ecosystems). However, molecular data are rarely used to guide spatial conservation decision-making. Here, we bridge the fields of molecular ecology (ME) and systematic conservation planning (SCP) (the 'why') to build a foundation for the inclusion of molecular data into spatial conservation planning tools (the 'how'), and provide a practical guide for implementing this integrative approach for both conservation planners and molecular ecologists. The proposed framework enhances interdisciplinary capacity, which is crucial to achieving the ambitious global conservation goals envisioned for the next decade.


Asunto(s)
Conservación de los Recursos Naturales , Ecosistema , Ecología , Biodiversidad , Evolución Biológica
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