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1.
Conserv Biol ; 29(4): 1217-1227, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25873240

RESUMO

Systematic conservation planning aims to design networks of protected areas that meet conservation goals across large landscapes. The optimal design of these conservation networks is most frequently based on the modeled habitat suitability or probability of occurrence of species, despite evidence that model predictions may not be highly correlated with species density. We hypothesized that conservation networks designed using species density distributions more efficiently conserve populations of all species considered than networks designed using probability of occurrence models. To test this hypothesis, we used the Zonation conservation prioritization algorithm to evaluate conservation network designs based on probability of occurrence versus density models for 26 land bird species in the U.S. Pacific Northwest. We assessed the efficacy of each conservation network based on predicted species densities and predicted species diversity. High-density model Zonation rankings protected more individuals per species when networks protected the highest priority 10-40% of the landscape. Compared with density-based models, the occurrence-based models protected more individuals in the lowest 50% priority areas of the landscape. The 2 approaches conserved species diversity in similar ways: predicted diversity was higher in higher priority locations in both conservation networks. We conclude that both density and probability of occurrence models can be useful for setting conservation priorities but that density-based models are best suited for identifying the highest priority areas. Developing methods to aggregate species count data from unrelated monitoring efforts and making these data widely available through ecoinformatics portals such as the Avian Knowledge Network will enable species count data to be more widely incorporated into systematic conservation planning efforts.


Mejoría de la Efectividad de la Planeación Sistemática de la Conservación con Datos de Densidad Resumen La planeación sistemática de la conservación tiene como meta diseñar redes de áreas protegidas que cumplan con objetivos de conservación a lo largo de grandes paisajes. El diseño óptimo de estas redes de conservación se basa con mayor frecuencia en modelos de idoneidad de hábitat o probabilidad de occurrencia de especies, a pesar de la evidencia existente de que las predicciones de esos modelos pueden no estar fuertemente correlacionadas con la densidad de especies. Hipotetizamos que las redes de conservación diseñadas con las distribuciones de la densidad de especies conservan con mayor eficiencia a las poblaciones de todas las especies consideradas que las redes diseñadas con modelos de probabilidad de occurencia. Para probar esta hipótesis usamos el algoritmo Zonation de planeación de la conservación para evaluar los diseños de redes de conservación basados en la probabilidad de ocurrencia versus los modelos de densidad para 26 especies de aves terrestres en el noroeste del Pacífico en los Estados Unidos. Evaluamos la efectividad de cada red de conservación con base en las densidades pronosticadas de cada especie y la diversidad de especies pronosticada. Las clasificaciones de Zonation de los modelos de alta densidad protegieron a más individuos por especie cuando las redes protegieron el 10-40% de la más alta prioridad del paisaje. Comparado con los modelos basados en la densidad, los modelos basados en la ocurrencia protegieron a más individuos en el 50% más bajo de las áreas prioritarias de los paisajes. Las dos estrategias conservaron la diversidad de especies de formas similares: la diversidad pronosticada fue más alta en las localidades de alta prioridad en ambas redes de conservación. Concluimos que tanto los modelos de densidad como los de probabilidad de ocurrencia pueden ser útiles para establecer prioridades de conservación, pero que los modelos basados en la densidad son más adecuados para identificar las áreas de más alta prioridad. Desarrollar métodos para agregar datos de conteos de especies a partir de esfuerzos de monitoreo no relacionados y hacer que estos datos estén disponibles en portales eco-informáticos como la Avian Knowledge Network permitirá que los datos de conteos de especies se incorporen más ampliamente en esfuerzos de planeación sistemática de la conservación.


Assuntos
Biodiversidade , Aves/fisiologia , Conservação dos Recursos Naturais/métodos , Ecossistema , Animais , California , Modelos Biológicos , Oregon , Densidade Demográfica , Probabilidade , Washington
2.
PLoS One ; 16(1): e0245287, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33428680

RESUMO

Patients with locally/regionally advanced melanoma were treated with neoadjuvant combination immunotherapy with high-dose interferon α-2b (HDI) and ipilimumab in a phase I clinical trial. Tumor specimens were obtained prior to the initiation of neoadjuvant therapy, at the time of surgery and progression if available. In this study, gene expression profiles of tumor specimens (N = 27) were investigated using the NanoString nCounter® platform to evaluate associations with clinical outcomes (pathologic response, radiologic response, relapse-free survival (RFS), and overall survival (OS)) and define biomarkers associated with tumor response. The Tumor Inflammation Signature (TIS), an 18-gene signature that enriches for response to Programmed cell death protein 1 (PD-1) checkpoint blockade, was also evaluated for association with clinical response and survival. It was observed that neoadjuvant ipilimumab-HDI therapy demonstrated an upregulation of immune-related genes, chemokines, and transcription regulator genes involved in immune cell activation, function, or cell proliferation. Importantly, increased expression of baseline pro-inflammatory genes CCL19, CD3D, CD8A, CD22, LY9, IL12RB1, C1S, C7, AMICA1, TIAM1, TIGIT, THY1 was associated with longer OS (p < 0.05). In addition, multiple genes that encode a component or a regulator of the extracellular matrix such as MMP2 and COL1A2 were identified post-treatment as being associated with longer RFS and OS. In all baseline tissues, high TIS scores were associated with longer OS (p = 0.0166). Also, downregulated expression of cell proliferation-related genes such as CUL1, CCND1 and AAMP at baseline was associated with pathological and radiological response (unadjusted p < 0.01). In conclusion, we identified numerous genes that play roles in multiple biological pathways involved in immune activation, immune suppression and cell proliferation correlating with pathological/radiological responses following neoadjuvant immunotherapy highlighting the complexity of immune responses modulated by immunotherapy. Our observations suggest that TIS may be a useful biomarker for predicting survival outcomes with combination immunotherapy.


Assuntos
Antígeno CTLA-4/antagonistas & inibidores , Inflamação/genética , Interferon-alfa/uso terapêutico , Melanoma/imunologia , Melanoma/patologia , Neoplasias Cutâneas/imunologia , Neoplasias Cutâneas/patologia , Transcrição Gênica , Antígeno CTLA-4/metabolismo , Terapia Combinada , Intervalo Livre de Doença , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Imunoterapia , Interferon-alfa/farmacologia , Ipilimumab/uso terapêutico , Melanoma/tratamento farmacológico , Melanoma/genética , Terapia Neoadjuvante , Recidiva Local de Neoplasia/genética , Recidiva Local de Neoplasia/patologia , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/genética , Análise de Sobrevida , Transcrição Gênica/efeitos dos fármacos , Resultado do Tratamento
3.
J Immunother Cancer ; 7(1): 15, 2019 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-30665466

RESUMO

BACKGROUND: Clinical benefit from checkpoint inhibitors has been associated in a tumor-agnostic manner with two main tumor traits. The first is tumor antigenicity, which is typically measured by tumor mutation burden, microsatellite instability (MSI), or Mismatch Repair Deficiency using gene sequence platforms and/or immunohistochemistry. The second is the presence of a pre-existing adaptive immune response, typically measured by immunohistochemistry (e.g. single analyte PD-L1 expression) and/or gene expression signatures (e.g. tumor "inflamed" phenotype). These two traits have been shown to provide independent predictive information. Here we investigated the potential of using gene expression to predict tumor MSI, thus enabling the measurement of both tumor antigenicity and the level of tumor inflammation in a single assay, possibly reducing sample requirement, turn-around time, and overall cost. METHODS: Using The Cancer Genome Atlas RNA-seq datasets with the greatest MSI-H incidence, i.e. those from colon (n = 208), stomach (n = 269), and endometrial (n = 241) cancers, we trained an algorithm to predict tumor MSI from under-expression of the mismatch repair genes MLH1, PMS2, MSH2, and MSH6 and from 10 additional genes with strong pan-cancer associations with tumor hypermutation. The algorithms were validated on the NanoString nCounter™ platform in independent cohorts of colorectal (n = 52), endometrial (n = 11), and neuroendocrine (n = 4) tumors pre-characterized using the MMR immunohistochemistry assay. RESULTS: In the validation cohorts, the algorithm showed high prediction accuracy of tumor MSI status, with sensitivity of at least 88% attained at thresholds chosen to achieve 100% specificity. Furthermore, MSI status was compared to the Tumor Inflammation Signature (TIS), an analytically validated diagnostic assay which measures a suppressed adaptive immune response in the tumor and enriches for response to immune checkpoint blockade. TIS score was largely independent of MSI status, suggesting that measuring both parameters may identify more patients that would respond to immune checkpoint blockade than either assay alone. CONCLUSIONS: Development of a gene expression signature of MSI status raises the possibility of a combined diagnostic assay on a single platform which measures both tumor antigenicity and presence of a suppressed adaptive immune response. Such an assay would have significant advantages over multi-platform assays for both ease of use and turnaround time and could lead to a diagnostic test with improved clinical performance.


Assuntos
Algoritmos , Neoplasias do Colo/genética , Reparo de Erro de Pareamento de DNA/genética , Neoplasias do Endométrio/genética , Instabilidade de Microssatélites , Neoplasias Gástricas/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , RNA-Seq
5.
Methods Mol Biol ; 477: 331-42, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19082958

RESUMO

In order to develop a more complete understanding of the genes required for resistance to oxidative DNA damage, we devised methods to identify genes that can prevent or repair oxidative DNA damage. These methods use the oxidative mutator phenotype of a repair deficient E. coli strain to measure the antimutator effect resulting from the expression of human cDNAs. The method can be adapted to characterize the function, and to determine the active site domains, of putative antimutator genes. Since bacteria do not contain subcellular compartments, genes that function in mitochondria, the cytoplasm, or the nucleus can be identified. Methods to determine the localization of genes in their normal host organism are also described.


Assuntos
Genes , Genômica/métodos , Oxirredução , Bioensaio , DNA Complementar/genética , Imunofluorescência , Células HeLa , Humanos , Peróxido de Hidrogênio/farmacologia , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Proteínas Mitocondriais , Mutagênese/efeitos dos fármacos , Mutação/genética , Compostos Orgânicos/metabolismo , Oxirredução/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Proteínas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Coloração e Rotulagem
6.
PeerJ ; 6: e5147, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30042882

RESUMO

BACKGROUND: Between 2013 and 2015, a large part of the western United States, including the Central Valley of California, sustained an extreme drought. The Central Valley is recognized as a region of hemispheric importance for waterbirds, which use flooded agriculture and wetlands as habitat. Thus, the impact of drought on the distribution of surface water needed to be assessed to understand the effects on waterbird habitat availability. METHODS: We used remote sensing data to quantify the impact of the recent extreme drought on the timing and extent of waterbird habitat during the non-breeding season (July-May) by examining open water in agriculture (rice, corn, and other crops) and managed wetlands across the Central Valley. We assessed the influence of habitat incentive programs, particularly The Nature Conservancy's BirdReturns and The Natural Resources Conservation Service's Waterbird Habitat Enhancement Program (WHEP), at offsetting habitat loss related to drought. RESULTS: Overall, we found statistically significant declines in open water in post-harvest agriculture (45-80% declines) and in managed wetlands (39-60% declines) during the 2013-2015 drought compared to non-drought years during the period of 2000-2011. Crops associated with the San Joaquin Basin, specifically corn, as well as wetlands in that part of the Central Valley exhibited larger reductions in open water than rice and wetlands in the Sacramento Valley. Semi-permanent wetlands on protected lands had significantly lower (39-49%) open water in the drought years than those on non-protected lands while seasonal wetlands on protected lands had higher amounts of open water. A large fraction of the daily open water in rice during certain times of the year, particularly in the fall for BirdReturns (61%) and the winter for WHEP (100%), may have been provided through incentive programs which underscores the contribution of these programs. However, further assessment is needed to know how much the incentive programs directly offset the impact of drought in post-harvest rice by influencing water management or simply supplemented funding for activities that might have been done regardless. DISCUSSION: Our landscape analysis documents the significant impacts of the recent extreme drought on freshwater wetland habitats in the Central Valley, the benefits of incentive programs, and the value of using satellite data to track surface water and waterbird habitats. More research is needed to understand subsequent impacts on the freshwater dependent species that rely on these systems and how incentive programs can most strategically support vulnerable species during future extreme drought.

7.
BMC Cell Biol ; 8: 13, 2007 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-17391516

RESUMO

BACKGROUND: The NCOA7 gene product is an estrogen receptor associated protein that is highly similar to the human OXR1 gene product, which functions in oxidation resistance. OXR genes are conserved among all sequenced eukaryotes from yeast to humans. In this study we examine if NCOA7 has an oxidation resistance function similar to that demonstrated for OXR1. We also examine NCOA7 expression in response to oxidative stress and its subcellular localization in human cells, comparing these properties with those of OXR1. RESULTS: We find that NCOA7, like OXR1 can suppress the oxidative mutator phenotype when expressed in an E. coli strain that exhibits an oxidation specific mutator phenotype. Moreover, NCOA7's oxidation resistance function requires expression of only its carboxyl-terminal domain and is similar in this regard to OXR1. We find that, in human cells, NCOA7 is constitutively expressed and is not induced by oxidative stress and appears to localize to the nucleus following estradiol stimulation. These properties of NCOA7 are in striking contrast to those of OXR1, which is induced by oxidative stress, localizes to mitochondria, and appears to be excluded, or largely absent from nuclei. CONCLUSION: NCOA7 most likely arose from duplication. Like its homologue, OXR1, it is capable of reducing the DNA damaging effects of reactive oxygen species when expressed in bacteria, indicating the protein has an activity that can contribute to oxidation resistance. Unlike OXR1, it appears to localize to nuclei and interacts with the estrogen receptor. This raises the possibility that NCOA7 encodes the nuclear counterpart of the mitochondrial OXR1 protein and in mammalian cells it may reduce the oxidative by-products of estrogen metabolite-mediated DNA damage.


Assuntos
Peptídeos e Proteínas de Sinalização Intracelular/fisiologia , Estresse Oxidativo , Proteínas/química , Núcleo Celular/metabolismo , Sequência Conservada , Dano ao DNA , Escherichia coli , Células Eucarióticas , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Peróxido de Hidrogênio/farmacologia , Peptídeos e Proteínas de Sinalização Intracelular/química , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas Mitocondriais , Família Multigênica , Coativadores de Receptor Nuclear , Estrutura Terciária de Proteína/fisiologia , Proteínas/genética , Proteínas/fisiologia , Células Tumorais Cultivadas
8.
Mol Cell Biol ; 24(8): 3180-7, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15060142

RESUMO

Reactive oxygen species (ROS) are critical molecules produced as a consequence of aerobic respiration. It is essential for cells to control the production and activity of such molecules in order to protect the genome and regulate cellular processes such as stress response and apoptosis. Mitochondria are the major source of ROS within the cell, and as a result, numerous proteins have evolved to prevent or repair oxidative damage in this organelle. The recently discovered OXR1 gene family represents a set of conserved eukaryotic genes. Previous studies of the yeast OXR1 gene indicate that it functions to protect cells from oxidative damage. In this report, we show that human and yeast OXR1 genes are induced by heat and oxidative stress and that their proteins localize to the mitochondria and function to protect against oxidative damage. We also demonstrate that mitochondrial localization is required for Oxr1 protein to prevent oxidative damage.


Assuntos
Regulação da Expressão Gênica , Mitocôndrias/metabolismo , Proteínas/metabolismo , Saccharomyces cerevisiae/metabolismo , Teste de Complementação Genética , Células HeLa , Temperatura Alta , Humanos , Peróxido de Hidrogênio/metabolismo , Proteínas Mitocondriais , Oxidantes/metabolismo , Oxirredução , Estresse Oxidativo , Proteínas/genética , Espécies Reativas de Oxigênio/metabolismo , Saccharomyces cerevisiae/citologia , Saccharomyces cerevisiae/genética , Distribuição Tecidual
9.
Sci Adv ; 3(8): e1700707, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28845449

RESUMO

In an era of unprecedented and rapid global change, dynamic conservation strategies that tailor the delivery of habitat to when and where it is most needed can be critical for the persistence of species, especially those with diverse and dispersed habitat requirements. We demonstrate the effectiveness of such a strategy for migratory waterbirds. We analyzed citizen science and satellite data to develop predictive models of bird populations and the availability of wetlands, which we used to determine temporal and spatial gaps in habitat during a vital stage of the annual migration. We then filled those gaps using a reverse auction marketplace to incent qualifying landowners to create temporary wetlands on their properties. This approach is a cost-effective way of adaptively meeting habitat needs for migratory species, optimizes conservation outcomes relative to investment, and can be applied broadly to other conservation challenges.

10.
PLoS One ; 7(9): e45656, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23029164

RESUMO

The serum prostate-specific antigen (PSA) test has a high false positive rate. As a single marker, PSA provides limited diagnostic information. A multi-marker test capable of detecting not only tumors but also the potentially lethal ones provides an unmet clinical need. Using the nanoString nCounter gene expression system, a 20-gene multiplex test was developed based on digital gene counting of RNA transcripts in urine as a means to detect prostate cancer. In this test, voided urine is centrifuged to pellet cells and the purified RNA is amplified for hybridization to preselected probesets. Amplification of test cell line RNA appeared not to introduce significant bias, and the counts matched well with gene abundance levels as measured by DNA microarrays. For data analysis, the individual counts were compared to that of ß2 microglobulin, a housekeeping gene. Urine samples of 5 pre-operative cases and 2 non-cancer were analyzed. Pathology information was then retrieved. Signals for a majority of the genes were low for non-cancer and low Gleason scores, and 6/6 known prostate cancer markers were positive in the cases. One case of Gleason 4+5 showed, in contrast, strong signals for all cancer-associated markers, including CD24. One non-cancer also showed signals for all 6 cancer markers, and this man might harbor an undiagnosed cancer. This multiplex test assaying a natural waste product can potentially be used for screening, early cancer detection and patient stratification. Diagnostic information is gained from the RNA signatures that are associated with cell types of prostate tumors.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias da Próstata/genética , RNA Mensageiro/urina , Biomarcadores Tumorais/urina , Estudos de Casos e Controles , Linhagem Celular Tumoral , Perfilação da Expressão Gênica , Humanos , Imuno-Histoquímica , Masculino , Reação em Cadeia da Polimerase Multiplex , Análise de Sequência com Séries de Oligonucleotídeos , Neoplasias da Próstata/urina
11.
Int J Cancer ; 119(9): 2225-7, 2006 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-16823845

RESUMO

The major etiological agent in skin cancer is exposure to UV-irradiation and the concomitant DNA damage. UV-induced DNA lesions, such as thymine dimers, block DNA synthesis by the major DNA polymerases and inhibit the progression of DNA replication. Bypass of thymine dimers and related lesions is dependent on the translesion polymerase DNA polymerase eta (Poleta). In the inherited disorder, xeroderma pigmentosum variant (XPV), inactivation of Poleta results in extreme sensitivity to UV light and a marked increase in the incidence of skin cancer. Here, we tested the hypothesis that somatic mutations and/or polymorphisms in the POLH gene that encodes Poleta are associated with the induction of UV-dependent skin cancers. We sequenced the exonic regions of the Poleta open reading frame in DNA from 17 paired samples of squamous cell skin carcinoma and adjacent histologically normal tissue. We analyzed approximately 120,000 nucleotides and detected no mutations in POLH in the tumors. However, we identified 6 different single-nucleotide polymorphisms, 3 of them previously undocumented, which were present in both the tumor and paired normal tissue. We conclude that neither mutations nor polymorphisms in the coding regions of POLH are required for the generation of human skin squamous cell carcinoma.


Assuntos
Carcinoma de Células Escamosas/genética , DNA Polimerase Dirigida por DNA/genética , Mutação , Neoplasias Cutâneas/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Sequência de Bases , Primers do DNA , Humanos , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , População Branca
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