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2.
Philos Trans R Soc Lond B Biol Sci ; 378(1867): 20210072, 2023 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-36373928

RESUMEN

Under the UN-Decade of Ecosystem Restoration and Bonn Challenge, second-growth forest is promoted as a global solution to climate change, degradation and associated losses of biodiversity and ecosystem services. Second growth is often invaded by alien tree species and understanding how this impacts carbon stock and biodiversity recovery is key for restoration planning. We assessed carbon stock and tree diversity recovery in second growth invaded by two Acacia species and non-invaded second growth, with associated edge effects, in the Brazilian Atlantic Forest. Carbon stock recovery in non-invaded forests was threefold lower than in invaded forests. Increasingly isolated, fragmented and deforested areas had low carbon stocks when non-invaded, whereas the opposite was true when invaded. Non-invaded forests recovered threefold to sixfold higher taxonomic, phylogenetic and functional diversity than invaded forest. Higher species turnover and lower nestedness in non-invaded than invaded forests underpinned higher abundance of threatened and endemic species in non-invaded forest. Non-invaded forests presented positive relationships between carbon and biodiversity, whereas in the invaded forests we did not detect any relationship, indicating that more carbon does not equal more biodiversity in landscapes with high vulnerability to invasive acacias. To deliver on combined climate change and biodiversity goals, restoration planning and management must consider biological invasion risk. This article is part of the theme issue 'Understanding forest landscape restoration: reinforcing scientific foundations for the UN Decade on Ecosystem Restoration'.


Asunto(s)
Acacia , Ecosistema , Especies Introducidas , Carbono , Filogenia , Bosques , Biodiversidad , Conservación de los Recursos Naturales
3.
J Histochem Cytochem ; 69(7): 437-449, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-34126796

RESUMEN

Colorectal cancer can develop through molecular, chromosomal, and epigenetic cumulative changes that transform the normal intestinal epithelium into the colorectal polyps, called conventional adenomas (CAs) or serrated polyps (SPs), recognized as precursors of invasive colorectal neoplasia. These benign lesions need to explore the morphology, histological diagnosis, and biomarkers profile to accurately characterize lesions with potential for evolution to cancer. This study aimed to correlate the immunohistochemical expression of Parkin and Adenomatous Polyposis Coli (APC; tumor suppressors), Human Apurinic/Apyrimidinic endonuclease 1 (APE1), and B-cell lymphoma-extra-large (Bcl-xL; oncogenic proteins) in sporadic colorectal polyps with clinical, endoscopic, and diagnostic data. Immunohistochemical analysis was performed on tissue microarray samples of 306 polyps. Based on the Allred score, the expressions were graduated in the cytoplasm and nucleus of superficial and cryptic cells. There was higher Parkin nuclear expression (p=0.006 and 0.010) and APC cytoplasmic expression in cryptic cells (p<0.001) in SPs. CAs, APE1 (p<0.001) and Bcl-xL (p<0.001) were more expressed in the nuclei and cytoplasms, respectively. These results are related to the biological role proposed for these proteins in cellular functions. They can contribute to the diagnosis criteria for polyps and improve the knowledge of biomarkers that could predict cancer development.


Asunto(s)
Proteína de la Poliposis Adenomatosa del Colon/metabolismo , Pólipos del Colon/genética , Pólipos del Colon/metabolismo , ADN-(Sitio Apurínico o Apirimidínico) Liasa/metabolismo , Regulación de la Expresión Génica , Ubiquitina-Proteína Ligasas/metabolismo , Proteína bcl-X/metabolismo , Proteína de la Poliposis Adenomatosa del Colon/genética , ADN-(Sitio Apurínico o Apirimidínico) Liasa/genética , Humanos , Ubiquitina-Proteína Ligasas/genética , Proteína bcl-X/genética
4.
Rev. biol. trop ; 69(2)jun. 2021.
Artículo en Español | LILACS, SaludCR | ID: biblio-1387632

RESUMEN

Resumen Introducción: El banco de semillas en el suelo es uno de los indicadores ecológicos más importantes para la evaluación y monitoreo de recuperación de ecosistemas degradados. Así mismo, actualmente indicadores ecológicos de restauración son usados en áreas afectadas por la ruptura de la represa de relaves de Fundão en Mariana, Minas Gerais, Brasil. Objetivo: En este estudio se evaluó la variación de la riqueza, composición de especies, densidad y parámetros fitosociológicos del banco de semillas en dos profundidades de relaves mineros en Mariana, municipio de Mariana, Minas Gerais, Brasil. Métodos: Se recolectaron 15 muestras por nivel de profundidad, en la capa superior (Profundidad1, P1 = 0-2.5 cm) y capa inferior (Profundidad2, P2 = 2.5-5.0 cm) del relave de minería para examinar el banco de semillas viable, que luego se colocó en un invernadero para la germinación. Posteriormente se contaron e identificaron semanalmente todos los individuos de cada especie durante un período de seis meses. Resultados: Se demostró que existe un banco de semillas en las capas superficiales de relaves mineros acumulados en las áreas afectadas de Mariana, con una marcada diferencia entre profundidades en términos de riqueza de especies y densidad de individuos. Se observó una mayor riqueza y número de individuos en P1, (1 165 semillas germinadas), pertenecientes a 18 familias y 47 especies, en comparación a P2 (197 individuos), pertenecientes a 12 familias y 23 especies. El banco de semillas de la capa P1 está influenciado por la lluvia de semillas del bosque cercano. Por otro lado, el banco de semillas de P2, puede ser característico de los relaves mineros. Conclusiones: El banco de semillas estudiado puede tener efectos positivos sobre la recuperación en el área de estudio, debido a la alta proporción de especies nativas, pioneras y anemocóricas típicas de etapas iniciales de sucesión secundaria.


Abstract Introduction: The soil seed bank is one of the most important ecological indicators for evaluating and monitoring the resilience of degraded ecosystems. Likewise, ecological restoration indicators are currently used in areas affected by the rupture of the Fundão tailings dam in Mariana, Minas Gerais, Brazil. Objective: To evaluate the seed bank at two depths of areas affected by mining tailings, Mariana municipality, Minas Gerais, Brazil. Methods: 15 samples (40 × 40 cm) were collected per level of depth, in the upper layer (Depth1, P1 = 0-2.5 cm), and lower layer (Depth2, P2 = 2.5-5.0 cm) of the mining tailings to survey the viable seed bank, which was later placed in a greenhouse for germination and seedling identification. The samples were placed in plastic trays to germinate in the nursery, then counted and identified weekly for six months. Results: The results showed that there is a seed bank in the surface layers of accumulated mining tailings in the affected areas of Mariana, with a marked difference between depths in terms of species richness and density of individuals. Higher species richness and number of individuals were observed in P1, (1 165 germinated seeds), belonging to 18 families and 47 species, in comparison to P2 (197 individuals), belonging to 12 families and 23 species. Probably the seed bank of layer P1 is influenced by the rain of seeds from the nearby forest. On the other hand, the P2 seed bank can be characteristic of mining tailings. Conclusions: Seed bank patterns can have positive effects on forest resilience at the local-scale, due to the high proportion of native, pioneer and anemochorical species of early successional stages.


Asunto(s)
Banco de Semillas/tendencias , Minería , Regeneración , Brasil , Dispersión de Semillas
5.
An Acad Bras Cienc ; 93(1): e20201209, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33886703

RESUMEN

The restoration methods applied on the areas affected by the Fundão tailings dam collapse have a high priority in Mariana region. We evaluated the effect of different restoration methods and site preparation techniques, depth and seasonality on penetration resistance of tailings, and how these predictors affect tree aboveground biomass in areas affected by the Fundão dam collapse in Mariana, Brazil. No significant differences in penetration resistance and aboveground biomass between treatments were observed, but significant differences were observed between seasonal periods. The main univariate model explained the significant effects of depth and seasonality, mainly by a negatively wet effect on penetration resistance. According to the best models (univariate and multivariate) were those that had depth as a predictor. This study showed how penetration resistance can be an indicator to select the best period for restoration process in areas affected by the collapse of the Fundão dam, but no limit to the aboveground biomass recovery on tailing.


Asunto(s)
Minería , Colapso de la Estructura , Biomasa , Brasil , Monitoreo del Ambiente , Bosques
6.
Int J Gynecol Cancer ; 30(6): 717-723, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32376737

RESUMEN

OBJECTIVE: Despite good prognosis for patients with low-risk endometrial cancer, a small subset of women with low-grade/low-stage endometrial cancer experience disease recurrence and death. The aim of this study was to characterize clinical features and mutational profiles of recurrent, low-grade, non-myoinvasive, 'ultra-low risk' endometrioid endometrial adenocarcinomas. METHODS: We retrospectively identified patients with International Federation of Gynecology and Obstetrics (FIGO) stage IA endometrioid endometrial cancers who underwent primary surgery at our institution, between January 2009 and February 2017, with follow-up of ≥12 months. 'Ultra-low risk' was defined as FIGO tumor grade 1, non-myoinvasive, and lacking lymphovascular space invasion. Tumor-normal profiling using massively parallel sequencing targeting 468 genes was performed. Microsatellite instability was assessed using MSIsensor. DNA mismatch repair (MMR) protein proficiency was determined by immunohistochemistry. RESULTS: A total of 486 patients with ultra-low risk endometrioid endometrial cancers were identified: 14 (2.9%) of 486 patients developed a recurrence. Median follow-up for non-recurrent endometrioid endometrial cancers: 34 (range 12-116) months; for recurrent endometrioid endometrial cancers: 50.5 (range 20-116) months. Patients with recurrent disease were older, had lower body mass index, and were most commonly non-White (p=0.025, p<0.001, and p<0.001, respectively). Other clinical characteristics did not differ. MMR immunohistochemistry was obtained for 211 (43%) tumors: 158 (75%) MMR-proficient and 53 (25%) MMR-deficient. Primary tumors of 9 recurrent and 27 non-recurrent endometrioid endometrial cancers underwent mutational profiling. Most were microsatellite stable (6/9, 67% recurrent; 25/27, 93% non-recurrent). Recurrent PTEN and PIK3CA mutations were present in both groups. Exon 3 CTNNB1 hotspot mutations were found in 4/9 (44%) recurrent and 8/27 (30%) non-recurrent (p=0.44). CONCLUSIONS: Patients diagnosed with ultra-low risk endometrioid endometrial cancers have an overall excellent prognosis. However, in our study, 2.9% of patients with no identifiable clinical or pathologic risk factors developed recurrence. Further work is warranted to elucidate the mechanism for recurrence in this population.


Asunto(s)
Carcinoma Endometrioide/genética , Enzimas Reparadoras del ADN/genética , Neoplasias Endometriales/genética , Recurrencia Local de Neoplasia/epidemiología , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma Endometrioide/epidemiología , Neoplasias Endometriales/epidemiología , Femenino , Humanos , Inestabilidad de Microsatélites , Persona de Mediana Edad , Ciudad de Nueva York/epidemiología , Estudios Retrospectivos
7.
Nat Commun ; 11(1): 44, 2020 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-31896750

RESUMEN

Sclerosing stromal tumor (SST) of the ovary is a rare type of sex cord-stromal tumor (SCST), whose genetic underpinning is currently unknown. Here, using whole-exome, targeted capture and RNA-sequencing, we report recurrent FHL2-GLI2 fusion genes in 65% (17/26) of SSTs and other GLI2 rearrangements in additional 15% (4/26) SSTs, none of which are detected in other types of SCSTs (n = 48) or common cancer types (n = 9,950). The FHL2-GLI2 fusions result in transcriptomic activation of the Sonic Hedgehog (SHH) pathway in SSTs. Expression of the FHL2-GLI2 fusion in vitro leads to the acquisition of phenotypic characteristics of SSTs, increased proliferation, migration and colony formation, and SHH pathway activation. Targeted inhibition of the SHH pathway results in reversal of these oncogenic properties, indicating its role in the pathogenesis of SSTs. Our results demonstrate that the FHL2-GLI2 fusion is likely the oncogenic driver of SSTs, defining a genotypic-phenotypic correlation in ovarian neoplasms.


Asunto(s)
Proteínas con Homeodominio LIM/genética , Proteínas Musculares/genética , Proteínas Nucleares/genética , Proteínas de Fusión Oncogénica/genética , Neoplasias Ováricas/genética , Tumores de los Cordones Sexuales y Estroma de las Gónadas/genética , Factores de Transcripción/genética , Proteína Gli2 con Dedos de Zinc/genética , Adolescente , Adulto , Femenino , Dosificación de Gen , Regulación Neoplásica de la Expresión Génica , Proteínas Hedgehog/genética , Proteínas Hedgehog/metabolismo , Humanos , Persona de Mediana Edad , Mutación , Proteínas de Fusión Oncogénica/metabolismo , Neoplasias Ováricas/patología , Esclerosis , Tumores de los Cordones Sexuales y Estroma de las Gónadas/patología , Células del Estroma/patología , Secuenciación del Exoma , Adulto Joven
8.
Glob Chang Biol ; 26(2): 509-522, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31486174

RESUMEN

Tropical forests store large amounts of carbon and high biodiversity, but are being degraded at alarming rates. The emerging global Forest and Landscape Restoration (FLR) agenda seeks to limit global climate change by removing carbon dioxide from the atmosphere through the growth of trees. In doing so, it may also protect biodiversity as a free cobenefit, which is vital given the massive shortfall in funding for biodiversity conservation. We investigated whether natural forest regeneration on abandoned pastureland offers such cobenefits, focusing for the first time on the recovery of taxonomic diversity (TD), phylogenetic diversity (PD) and functional diversity (FD) of trees, including the recovery of threatened and endemic species richness, within isolated secondary forest (SF) fragments. We focused on the globally threatened Brazilian Atlantic Forest, where commitments have been made to restore 1 million hectares under FLR. Three decades after land abandonment, regenerating forests had recovered ~20% (72 Mg/ha) of the above-ground carbon stocks of a primary forest (PF), with cattle pasture containing just 3% of stocks relative to PFs. Over this period, SF recovered ~76% of TD, 84% of PD and 96% of FD found within PFs. In addition, SFs had on average recovered 65% of threatened and ~30% of endemic species richness of primary Atlantic forest. Finally, we find positive relationships between carbon stock and tree diversity recovery. Our results emphasize that SF fragments offer cobenefits under FLR and other carbon-based payments for ecosystem service schemes (e.g. carbon enhancements under REDD+). They also indicate that even isolated patches of SF could help to mitigate climate change and the biodiversity extinction crisis by recovering species of high conservation concern and improving landscape connectivity.


Asunto(s)
Ecosistema , Bosques , Animales , Biodiversidad , Brasil , Bovinos , Conservación de los Recursos Naturales , Filogenia , Clima Tropical
9.
Nat Ecol Evol ; 3(6): 928-934, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-31011177

RESUMEN

Tropical forests are converted at an alarming rate for agricultural use and pastureland, but also regrow naturally through secondary succession. For successful forest restoration, it is essential to understand the mechanisms of secondary succession. These mechanisms may vary across forest types, but analyses across broad spatial scales are lacking. Here, we analyse forest recovery using 1,403 plots that differ in age since agricultural abandonment from 50 sites across the Neotropics. We analyse changes in community composition using species-specific stem wood density (WD), which is a key trait for plant growth, survival and forest carbon storage. In wet forest, succession proceeds from low towards high community WD (acquisitive towards conservative trait values), in line with standard successional theory. However, in dry forest, succession proceeds from high towards low community WD (conservative towards acquisitive trait values), probably because high WD reflects drought tolerance in harsh early successional environments. Dry season intensity drives WD recovery by influencing the start and trajectory of succession, resulting in convergence of the community WD over time as vegetation cover builds up. These ecological insights can be used to improve species selection for reforestation. Reforestation species selected to establish a first protective canopy layer should, among other criteria, ideally have a similar WD to the early successional communities that dominate under the prevailing macroclimatic conditions.


Asunto(s)
Clima Tropical , Madera , Ecología , Bosques , Árboles
10.
Acta amaz ; 48(3): 248-256, July-Sept. 2018. map, ilus, tab
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1455360

RESUMEN

Although inselbergs from around the world are iconic ecosystems, little is known on the underlying mechanisms of community assembly, especially in their characteristic patchy outcrop vegetation. Environmental constraints are expected to cause phylogenetic clustering when ecological niches are conserved within evolutionary lineages. We tested whether vegetation patches from rock outcrops of the Piedra La Tortuga Natural Monument, in the northern Amazon region, are phylogenetically clustered, indicating that environmental filtering is the dominant driver of community assemblage therein. We classified all patches according to their size as very small (< 1 m2), small (1-4 m2), medium-sized (4-8 m2), and large patches (8-15 m2). From each class, we randomly selected 10 patches, totalizing 40 patches covering 226 m2. All individuals found in the 40 isolated patches were identified to the species level. We also correlated measurements of phylogenetic community structure with patch size. We found that species from patches are restricted to the clades monocots, fabids, malvids, and lamiids. We conclude that vegetation in this rock outcrop is phylogenetically clustered. Furthermore, we found that phylogenetic turnover between pairs of patches increases with patch size, which is consistent with a scenario of higher environmental stress in smaller patches. Further research is necessary to identify nurse species in inselberg vegetation, which is pivotal for conservation and restoration of this particular ecosystem.


Ainda que os inselbergs ao redor do mundo sejam ecossistemas icônicos, pouco se sabe sobre os mecanismos subjacentes que estruturam suas comunidades vegetais, especialmente nas manchas de vegetação sobre afloramentos rochosos. Espera-se que as restrições ambientais causem agrupamento filogenético quando os nichos ecológicos são conservados dentro das linhagens evolutivas. Nós testamos se as manchas de vegetação dos afloramentos rochosos do Monumento Natural Piedra La Tortuga, no norte da região amazônica, apresentam indicadores filogenéticos de que a filtragem ambiental é o principal direcionador da estruturação da comunidade. Classificamos todas as manchas de acordo com seu tamanho como muito pequenas (<1 m2), pequenas (1-4 m2), médias (4-8 m2) e grandes (8-15 m2). Selecionamos aleatoriamente 10 manchas em cada classe de tamanho, totalizando 40 manchas cobrindo 226 m2. Todos os indivíduos encontrados nas 40 manchas foram identificados ao nível de espécie. Correlacionamos as medidas da estrutura filogenética da comunidade com o tamanho das manchas e encontramos que as espécies das manchas são restritas aos clados das monocotiledôneas, fabídeas, malvídeas e lamiídeas. Concluímos que a vegetação neste afloramento rochoso é agrupada filogeneticamente. Além disso, encontramos que o turnover filogenético entre pares de manchas aumenta com o tamanho da mancha, o que é consistente com um cenário de alto estresse ambiental nas manchas menores. São necessárias mais pesquisas para identificar espécies facilitadoras, que são fundamentais para a conservação e restauração destes ecossistemas.


Asunto(s)
Filogenia , Plantas/clasificación , Plantas/genética , Variación Genética , Ecosistema Amazónico
12.
Rev. biol. trop ; 66(2): 937-951, abr.-jun. 2018. tab, graf
Artículo en Español | LILACS, SaludCR | ID: biblio-977356

RESUMEN

Resumen Aunque los inselbergs son afloramientos rocosos icónicos con un alto valor biogeográfico, poco se conoce sobre los mecanismos responsables de la estructuración de comunidades vegetales. El objetivo de esta investigación fue evaluar cómo el tamaño de los parches de vegetación influye en la relación especie-área y distribución de la abundancia de especies de una comunidad en un inselberg del Monumento Natural "Piedra La Tortuga", región Guayana, Venezuela. Por este motivo, se establecieron tres preguntas de investigación: ¿Cuál es el efecto del tamaño de los parches sobre la riqueza de especies? ¿Qué tipo de modelo especie-área (SAR) presenta mejor ajuste en esos parches de vegetación? ¿Cómo es la distribución de las abundancias de las especies (SADs) es inducida por el tamaño de los parches? Se realizó un muestreo aleatorio estratificado en parches que oscilaron entre 0.34 y 14.8 m2, totalizando 40 unidades muestrales (226 m2). Todos los individuos encontrados en los 40 parches fueron identificados a nivel de especie. La composición florística en las diferentes muestras estuvo representada por 19 familias, 22 géneros y 24 especies, de las cuales 50 % son endémicas de inselbergs y dos están amenazadas de extinción. Se identificaron dos grupos de tamaños de parches (grandes 8-15 m2 y pequeños ≤ 7.9 m2) en relación a la abundancia y composición de especies, con diferencias significativas entre los grupos. Las curvas de acumulación de especies para cada grupo de tamaño de parche muestran una tendencia contrastante con marcadas diferencias en la riqueza observada entre los grupos de tamaños de parches. Las curvas de los modelos SADs tuvieron un ajuste significativo de la serie geométrica en las dos categorías de parches. El modelo SAR de la función potencia presentó los mejores ajustes especie-área, donde el aumento del área de los parches explicó un 82 % de la variación en el aumento del número de especies. Los resultados de este estudio demuestran por primera vez como el tamaño de los parches de vegetación de un inselberg tropical tiene una fuerte influencia sobre la riqueza, distribución de la abundancia y composición de especies. Así mismo, se determinó que el modelo geométrico SAD presentó el mejor ajuste en la comunidad en función del tamaño de los parches como un indicador de recursos, donde la abundancia de una especie puede ser equivalente a una proporción del espacio ocupado. También se presume que los cambios de tamaño de los parches, podría estar asociado con la disponibilidad de nutrientes y agua, como ha sido demostrado en otros ambientes de tierras secas. En algunos estudios se ha argumentado que la variación en la composición de especies entre los perfiles de vegetación de inselbergs tropicales está condicionada principalmente por la estructura del hábitat y el déficit hídrico. Sin embargo, no se había discutido cómo el tamaño de los parches de vegetación tiene un efecto en la riqueza. Los análisis SADs y SAR pueden proporcionar explicaciones complementarias sobre la estructuración de comunidades vegetales en inselbergs.


Abstract Although inselbergs are iconic rock outcrops with a high biogeographic value, little is known about drivers responsible for the plant community assembly. The aim of this research was to evaluate how the patch size distribution of vegetation influences the species-area relationship and species abundance distribution of a community in an inselberg of the "Piedra La Tortuga" Natural Monument of the Guayana region, Venezuela. In this context, three research questions were established: What is the effect of patch size on species richness? What species-area model (SAR) has the best fit in those vegetation patches? How is the distribution of species abundances (SADs) induced by the patch size distribution? A stratified random sampling was performed in patches ranging from 0.34 to 14.8 m2, totaling 40 sampling units (226 m2). All individuals found in the 40 patches were identified at species level. The floristic composition in the different samples was represented by 19 families, 22 genera and 24 species, of which 50 % are endemic to inselbergs and two, are threatened of extinction. Two groups of patch sizes were identified (large 8-15 m2 and small ≤ 7.9 m2) in relation to the abundance and composition of species. The species accumulation curves for each patch size group show a contrasting tendency with marked differences in the observed richness among patch size groups. The curves of the SADs models had a significant adjustment of the geometric series in the two categories of patches. The SAR model of the power function presented the best species-area adjustments, where the increase in patch area accounted for 82 % of the variation in the increase in the number of species. The results of this study demonstrate for the first time how vegetation patches of a tropical inselberg have a strong influence on richness, abundance distribution and species composition. Likewise, it was determined that the SAD geometric model presented the best fit in the community as a function of patch size as a resource indicator, where the abundance of a species can be equivalent to a proportion of the space occupied. It is also presumed that changes in patch sizes could be associated with nutrient and water availability, as has been demonstrated in other dryland environments. In some studies it has been argued that variation in species composition among vegetation profiles of tropical inselbergs is mainly conditioned by habitat structure and water deficit. However, it had not been discussed how the size of patches of vegetation has an effect on richness. SADs and SAR analyzes can provide complementary explanations on community assembly in inselbergs. Rev. Biol. Trop. 66(2): 937-951. Epub 2018 June 01.


Asunto(s)
Bosques , Sedimentos Geológicos , Tabebuia , Dispersión de las Plantas , Venezuela
13.
J Hepatol ; 69(2): 385-395, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29572095

RESUMEN

BACKGROUND AND AIMS: Although the majority of patients with non-alcoholic fatty liver disease (NAFLD) have only steatosis without progression, a sizeable fraction develop non-alcoholic steatohepatitis (NASH), which can lead to cirrhosis and hepatocellular carcinoma (HCC). Many established diet-induced mouse models for NASH require 24-52 weeks, which makes testing for drug response costly and time consuming. METHODS: We have sought to establish a murine NASH model with rapid progression of extensive fibrosis and HCC by using a western diet (WD), which is high-fat, high-fructose and high-cholesterol, combined with low weekly dose of intraperitoneal carbon tetrachloride (CCl4), which serves as an accelerator. RESULTS: C57BL/6J mice were fed a normal chow diet ±â€¯CCl4 or WD ±â€¯CCl4 for 12 and 24 weeks. Addition of CCl4 exacerbated histological features of NASH, fibrosis, and tumor development induced by WD, which resulted in stage 3 fibrosis at 12 weeks and HCC development at 24 weeks. Furthermore, whole liver transcriptomic analysis indicated that dysregulated molecular pathways in WD/CCl4 mice and immunologic features were similar to those of human NASH. CONCLUSIONS: Our mouse NASH model exhibits rapid progression of advanced fibrosis and HCC, and mimics histological, immunological and transcriptomic features of human NASH, suggesting that it will be a useful experimental tool for preclinical drug testing. LAY SUMMARY: A carefully characterized model has been developed in mice that recapitulates the progressive stages of human fatty liver disease, from simple steatosis, to inflammation, fibrosis and cancer. The functional pathways of gene expression and immune abnormalities in this model closely resemble human disease. The ease and reproducibility of this model make it ideal to study disease pathogenesis and test new treatments.


Asunto(s)
Dieta Occidental , Hígado Graso , Cirrosis Hepática , Neoplasias Hepáticas , Ratones Endogámicos C57BL , Animales , Tetracloruro de Carbono/farmacología , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Hígado Graso/etiología , Hígado Graso/inmunología , Hígado Graso/patología , Perfilación de la Expresión Génica/métodos , Inflamación/patología , Cirrosis Hepática/etiología , Cirrosis Hepática/inmunología , Cirrosis Hepática/patología , Neoplasias Hepáticas/etiología , Neoplasias Hepáticas/inmunología , Neoplasias Hepáticas/patología , Ratones , Reproducibilidad de los Resultados
14.
Dement Neuropsychol ; 10(1): 63-69, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-29213434

RESUMEN

We report the case of a patient with insidious onset and slowly progressive cognitive impairment, behavioral symptoms, temporal lobe seizures and delusional thoughts typical of delusional misidentification syndromes. Clinical presentation along with extensive diagnostic work-up revealed limbic encephalitis secondary to diffuse large B-cell lymphoma. The patient underwent immunotherapy with high-dose corticosteroid but no significant improvement was observed. No specific treatment for lymphoma was performed because the patient died of septic shock following a nosocomial respiratory infection. Delusional misidentification syndromes are an unusual and unique form of cognitive impairment in which a patient consistently misidentifies persons, places, objects, or events. Capgras syndrome is the most common subtype of this disorder, being defined by the recurrent and transient belief that someone close has been substituted by an imposter. These entities are generally associated with neurodegenerative diseases and psychiatric disturbances. Rare reports of associations between misidentification syndromes and autoimmune diseases such as multiple sclerosis have been published, but no papers address a correlation with limbic encephalitis or lymphoma.


Nós relatamos o caso de um paciente com início insidioso e lentamente progressivo de declínio cognitivo, sintomas comportamentais, crises convulsivas do lobo temporal e pensamentos delirantes típicos dos delírios monotemáticos de identificação. A apresentação clínica associada aos exames complementares levaram ao diagnóstico de encefalite límbica relacionada a linfoma difuso de grandes células B. O paciente foi submetido a imunoterapia com altas doses de corticoide sem melhora clínica. Não foi realizado tratamento específico para o linfoma em função do paciente ter evoluído para óbito por choque séptico secundário a infecção respiratória nosocomial. Os delírios monotemáticos de identificação representam uma forma única e incomum de comprometimento cognitivo nas quais o paciente consistentemente identifica de forma errônea pessoas, lugares, objetos ou eventos. A síndrome de Capgras é o subtipo mais comum dessas desordens, sendo definida como a crença recorrente e transitória que um impostor substituiu uma pessoa familiar. Essas entidades são geralmente relacionadas com doenças neurodegenerativas e distúrbios psiquiátricos. Raros relatos da associação entre os delírios monotemáticos de identificação e doenças autoimunes como esclerose múltipla foram publicados, porém não há artigos abordando a correlação com encefalite límbica ou linfoma.

15.
Autops Case Rep ; 5(3): 49-53, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26558248

RESUMEN

Gastrointestinal metastases from breast cancer are rare and generally occur several years after the diagnosis of the primary lesion. The diagnosis of gastric metastasis as the initial presentation of breast cancer is even rarer and can potentially mimic gastric carcinoma. We report the case of a 66-year-old female patient submitted to a total gastrectomy because of the histological diagnosis of undifferentiated gastric carcinoma. During the surgical procedure, biopsies of the peritoneum and the liver were performed, which were consistent with metastatic breast invasive lobular carcinoma (ILC). The primary lesion of the breast was detected during the post-operative period, when a 4-cm-long lesion was detected on physical examination and mammography. The revision of the gastric biopsy confirmed the diagnosis of ILC. The authors call attention to the rarity of gastrointestinal metastases as the initial presentation of breast ILC.

16.
Glob Chang Biol ; 21(9): 3455-68, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25832015

RESUMEN

Tropical forests store vast amounts of carbon and are the most biodiverse terrestrial habitats, yet they are being converted and degraded at alarming rates. Given global shortfalls in the budgets required to prevent carbon and biodiversity loss, we need to seek solutions that simultaneously address both issues. Of particular interest are carbon-based payments under the Reducing Emissions from Deforestation and Forest Degradation (REDD+) mechanism to also conserve biodiversity at no additional cost. One potential is for REDD+ to protect forest fragments, especially within biomes where contiguous forest cover has diminished dramatically, but we require empirical tests of the strength of any carbon and biodiversity cobenefits in such fragmented systems. Using the globally threatened Atlantic Forest landscape, we measured above-ground carbon stocks within forest fragments spanning 13 to 23 442 ha in area and with different degrees of isolation. We related these stocks to tree community structure and to the richness and abundance of endemic and IUCN Red-listed species. We found that increasing fragment size has a positive relationship with above-ground carbon stock and with abundance of IUCN Red-listed species and tree community structure. We also found negative relationships between distance from large forest block and tree community structure, endemic species richness and abundance, and IUCN Red-listed species abundance. These resulted in positive congruence between carbon stocks and Red-listed species, and the abundance and richness of endemic species, demonstrating vital cobenefits. As such, protecting forest fragments in hotspots of biodiversity, particularly larger fragments and those closest to sources, offers important carbon and biodiversity cobenefits. More generally, our results suggest that macroscale models of cobenefits under REDD+ have likely overlooked key benefits at small scales, indicating the necessity to apply models that include finer-grained assessments in fragmented landscapes rather than using averaged coarse-grained cells.


Asunto(s)
Biodiversidad , Secuestro de Carbono , Conservación de los Recursos Naturales , Bosque Lluvioso , Brasil , Modelos Biológicos , Clima Tropical
17.
Autops Case Rep ; 4(1): 53-57, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-28652993

RESUMEN

Breast malignancies, apart from skin cancer, are the leading cause of cancer from cancer among the female population. Unlike the high prevalence of primary mammary malignancies, metastases to the breast are uncommon, and account for only 0.2-2.7% of all malignancies affecting this organ. We report the case of a 35-year-old woman who sought medical care because of a breast lump. A mammogram suggested a breast tumor, which was biopsied. The histopathological workup resulted in the diagnosis of a metastasis from a medullary thyroid cancer. The authors review the most useful clinical, radiological, histological, and immunohistochemical features concerning extramammary malignancy to the breast.

18.
Rev. biol. trop ; 61(4): 1585-1595, oct.-dic. 2013. ilus, graf, tab
Artículo en Inglés | LILACS | ID: lil-703915

RESUMEN

Conservation and restoration projects involving abandoned cattle pastures pose several challenges. Restoration ecologists recognize that natural restoration is possible, but few species can successfully colonize degraded pastures. The aim of the present study was to evaluate whether land colonized by the tree Myracrodruon urundeuva increase the amount of habitat available for bird communities in Southeastern Brazil. We used fixed point counts within a 50m radius to compare the richness and composition of the bird community inhabiting naturally regenerated M. urundeuva with that an adjacent native forest remnant and a forest restored with planted Acacia spp. We recorded a total of 68 bird species. The M. urundeuva forest was able to provide valuable habitat for bird species, including more forest species, in comparison with the Acacia planting. These results indicate that M. urundeuva is a useful species for the ecological restoration of degraded pasture land.


La conservación y restauración de pastizales abandonados representan diversos retos. Los ecologistas reconocen que la restauración natural es posible, pero algunas especies pueden colonizar con éxito los pastizales degradados. El objetivo de este estudio fue evaluar si una zona de pastos colonizada por M. urundeuva puede aumentar la cantidad de hábitat disponible para las comunidades de aves en el sureste de Brasil. La metodología utilizada fue la de conteo de puntos en un radio de 50m para comparar la riqueza y composición de comunidades de aves en un pastizal regenerado por M. urundeuva con un remanente de bosque nativo y bosque restaurado mediante la plantación de Acacia spp. Se registró un total de 68 especies de aves. El área colonizada por M. urundeuva representa un hábitat importante para las aves, incluyendo especies forestales, en comparación con la plantación de Acacia spp. Estos resultados indican que M. urundeuva es una especie útil para la restauración ecológica de los pastizales degradados.


Asunto(s)
Animales , Bovinos , Aves/clasificación , Conservación de los Recursos Naturales , Árboles , Anacardiaceae/clasificación , Anacardiaceae/crecimiento & desarrollo , Brasil , Plantones/crecimiento & desarrollo , Semillas/crecimiento & desarrollo , Árboles/crecimiento & desarrollo
19.
Rev Biol Trop ; 61(4): 1585-95, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24432521

RESUMEN

Conservation and restoration projects involving abandoned cattle pastures pose several challenges. Restoration ecologists recognize that natural restoration is possible, but few species can successfully colonize degraded pastures. The aim of the present study was to evaluate whether land colonized by the tree Myracrodruon urundeuva increase the amount of habitat available for bird communities in Southeastern Brazil. We used fixed point counts within a 50 m radius to compare the richness and composition of the bird community inhabiting naturally regenerated M. urundeuva with that an adjacent native forest remnant and a forest restored with planted Acacia spp. We recorded a total of 68 bird species. The M. urundeuva forest was able to provide valuable habitat for bird species, including more forest species, in comparison with the Acacia planting. These results indicate that M. urundeuva is a useful species for the ecological restoration of degraded pasture land.


Asunto(s)
Aves/clasificación , Conservación de los Recursos Naturales , Árboles , Anacardiaceae/clasificación , Anacardiaceae/crecimiento & desarrollo , Animales , Brasil , Bovinos , Plantones/crecimiento & desarrollo , Semillas/crecimiento & desarrollo , Árboles/crecimiento & desarrollo
20.
An Acad Bras Cienc ; 84(3): 807-22, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22886165

RESUMEN

The aim of this study was to determine changes in composition, abundance and richness of species along a forest gradient with varying soils and flood regimes. The forests are located on the left bank of the lower Jucu River, in Jacarenema Natural Municipal Park, Espírito Santo. A survey of shrub/tree species was done in 80 plots, 5x25 m, equally distributed among the forests studied. We included in the sampling all individuals with >3.2 cm diameter at breast height (1.30 m). Soil samples were collected from the surface layer (0-10 cm) in each plot for chemical and physical analysis. The results indicate that a significant pedological gradient occurs, which is influenced by varying seasonal groundwater levels. Restinga forest formations showed significant differences in species richness, except for Non-flooded Forest and Non-flooded Forest Transition. The Canonical Correlation Analysis (CCA) showed that some species are distributed along the gradient under the combined influence of drainage, nutrient concentration and physical characteristics of the soil. Regarding the variables tested, flooding seems to be a more limiting factor for the establishment of plant species in Restinga forests than basic soil fertility attributes.


Asunto(s)
Biodiversidad , Inundaciones , Estaciones del Año , Suelo/análisis , Árboles/clasificación , Brasil , Densidad de Población , Especificidad de la Especie
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