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1.
PLoS One ; 10(7): e0132243, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26201071

RESUMO

Palaeobiogeographical and palaeodiversity patterns of scleractinian reef corals are generally biased due to uncertain taxonomy and a loss of taxonomic characters through dissolution and recrystallization of the skeletal aragonite in shallow marine limestones. Herein, we describe a fossil lobophylliid coral in mouldic preservation from the early middle Miocene Leitha Limestone of the Central Paratethys Sea (Vienna Basin, Austria). By using grey-scale image inversion and silicone rubber casts for the visualization of the original skeletal anatomy and the detection of distinct micromorphological characters (i.e. shape of septal teeth, granulation of septocostae) Parascolymia bracherti has been identified as a new species in spite of the dissolved skeleton. In the recent era, Parascolymia like all Lobophylliidae is restricted to the Indo-Pacific region, where it is represented by a single species. The new species proves the genus also in the Miocene Mediterranean reef coral province. A review of the spatio-temporal relationships of fossil corals related to Parascolymia indicates that the genus was probably rooted in the Eastern Atlantic‒Western Tethys region during the Paleocene to Eocene and reached the Indo-Pacific region not before the Oligocene. The revealed palaeobiogeographical pattern shows an obvious congruence with that of Acropora and tridacnine bivalves reflecting a gradual equatorwards retreat of the marine biodiversity center parallel to the Cenozoic climate deterioration.


Assuntos
Antozoários/classificação , Osso e Ossos/anatomia & histologia , Fósseis/anatomia & histologia , Animais , Antozoários/anatomia & histologia , Áustria , Recifes de Corais , Filogenia , Filogeografia
2.
BMC Cancer ; 15: 74, 2015 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-25884169

RESUMO

BACKGROUND: The tumor suppressor phosphatase and tensin homolog (PTEN) is a pleiotropic enzyme, inhibiting phosphatidyl-inositol-3 kinase (PI3K) signaling in the cytosol and stabilizing the genome in the nucleus. Nucleo-cytosolic partitioning is dependent on the post-translational modifications ubiquitinylation and sumoylation. This cellular compartmentalization of PTEN was investigated in lung neuroendocrine tumors (lung NET). METHODS: Tumor tissues from 192 lung NET patients (surgical specimens = 183, autopsies = 9) were investigated on tissue microarrays. PTEN was H-scored by two investigators in nucleus and cytosol using the monoclonal antibody 6H2.1. Results were correlated with immunoreactivity for USP7 (herpes virus-associated ubiquitin-specific protease 7) and SUMO2/3 (small ubiquitin-related modifier protein 2/3) as well as PTEN and p53 FISH gene status. Clinico-pathologic data including overall survival, proliferation rate and diagnostic markers (synaptophysin, chromogranin A, Mib-1, TTF-1) were recorded. RESULTS: The multicentre cohort included 58 typical carcinoids (TC), 42 atypical carcinoids (AC), 32 large cell neuroendocrine carcinomas (LCNEC) and 60 small cell lung carcinomas (SCLC). Carcinoids were smaller in size and had higher synaptophysin and chromogranin A, but lower TTF-1 expressions. Patients with carcinoids were predominantly female and 10 years younger than patients with LCNEC/SCLC. In comparison to the carcinoids, LCNEC/SCLC tumors presented a stronger loss of nuclear and cytosolic PTEN associated with a loss of PTEN and p53. Concomitantly, a loss of nuclear USP7 but increase of nuclear and cytosolic SUMO2/3 was found. Loss of nuclear and cytosolic PTEN, loss of nuclear USP7 and increase of cytosolic SUMO2/3 thus correlated with poor survival. Among carcinoids, loss of cytosolic PTEN was predominantly found in TTF1-negative larger tumors of male patients. Among SCLC, loss of both cytosolic and nuclear PTEN but not proliferation rate or tumor size delineated a subgroup with poorer survival (all p-values <0.05). CONCLUSIONS: Cellular ubiquitinylation and sumoylation likely influence the functional PTEN loss in high grade lung NET. Both nuclear and cytosolic PTEN immunoreactivity should be considered for correlation with clinico-pathologic parameters.


Assuntos
Núcleo Celular/metabolismo , Citosol/metabolismo , Neoplasias Pulmonares/patologia , Tumores Neuroendócrinos/patologia , PTEN Fosfo-Hidrolase/metabolismo , Ubiquitinação , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Masculino , Pessoa de Meia-Idade , Tumores Neuroendócrinos/genética , Tumores Neuroendócrinos/metabolismo , PTEN Fosfo-Hidrolase/genética , Prognóstico , Proteínas Modificadoras Pequenas Relacionadas à Ubiquitina/metabolismo , Análise de Sobrevida , Análise Serial de Tecidos , Proteína Supressora de Tumor p53/genética , Ubiquitina Tiolesterase/metabolismo , Peptidase 7 Específica de Ubiquitina , Adulto Jovem
3.
Cancer Genomics Proteomics ; 9(1): 51-4, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22210048

RESUMO

Lung cancer is the leading cause of all cancer deaths worldwide with suboptimal prognosis and treatment options. Therefore this study aimed to identify molecular characteristics with a predictive clinical utility which at the same time might represent novel therapeutic targets for human lung adenocarcinoma. Within this study mutations of v-Ki-RAS2 Kirsten rat sarcoma viral oncogene homolog (KRAS), a gene frequently mutated in lung adenocarcinoma, and their association with enzymatic activities, as assessed by activity-based proteomics, of members of the serine hydrolase (SH) superfamily, a large class of enzymes that have previously been linked to cancer was investigated. The results revealed that the activity of myeloblastin was significantly altered in the lung adenocarcinoma biopsies harboring a KRAS gene mutation. In conclusion myeloblastin is a potential therapeutic target for human lung adenocarcinoma, indicating that the combination of activity-based proteomics with mutational analysis is a valid approach for the discovery of novel biomarkers.


Assuntos
Adenocarcinoma/enzimologia , Adenocarcinoma/genética , Neoplasias Pulmonares/enzimologia , Neoplasias Pulmonares/genética , Mutação , Mieloblastina/metabolismo , Proteínas Proto-Oncogênicas/genética , Proteínas ras/genética , Adenocarcinoma/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Ativação Enzimática , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Mieloblastina/genética , Estadiamento de Neoplasias , Proteínas Proto-Oncogênicas p21(ras)
4.
Hydrobiologia ; 682(1): 131-141, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-26069346

RESUMO

Quantitative genetic studies in natural populations are of growing interest to speciation research since divergence is often believed to arise through micro-evolutionary change, caused by natural selection on functional morphological traits. The species flock of cichlid fishes in Africa's oldest lake, Lake Tanganyika, offers a rare opportunity to study this process. Using the cichlid species Tropheus moorii, we assessed the potential for microevolution in a set of morphological traits by estimating their quantitative genetic basis of variation. Two approaches were employed: (1) estimation of trait heritabilities (h2) in situ from a sample of wild caught fish, and (2) estimation of h2 from first generation offspring produced in a semi-natural breeding experiment. In both cases, microsatellite data were used to infer pedigree structure among the sampled individuals and estimates of h2 were made using an animal model approach. Although power was limited by the pedigree structures estimated (particularly in the wild caught sample), we nonetheless demonstrate the presence of significant additive genetic variance for aspects of morphology that, in the cichlid species Tropheus moorii, are expected to be functionally and ecologically important, and therefore likely targets of natural selection. We hypothesize that traits showing significant additive genetic variance, such as the mouth position have most likely played a key role in the adaptive evolution of the cichlid fish Tropheus moorii.

5.
Naturwissenschaften ; 98(2): 125-34, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21161156

RESUMO

Cichlids are an excellent model to study explosive speciation and adaptive radiation. Their evolutionary success has been attributed to their ability to undergo rapid morphological changes related to diet, and their particular breeding biology. Relatively minor changes in morphology allow for exploitation of novel food resources. The importance of phenotypic plasticity and genetically based differences for diversification was long recognized, but their relationship and relative magnitude remained unclear. We compared morphology of individuals of four wild populations of the Lake Tanganyika cichlid Tropheus moorii with their pond-raised F(1) offspring. The magnitude of morphological change via phenotypic plasticity between wild and pond-bred F(1) fish exceeds pairwise population differences by a factor of 2.4 (mean Mahalanobis distances). The genetic and environmental effects responsible for among population differentiation in the wild could still be recognized in the pond-bred F(1) fish. All four pond populations showed the same trends in morphological change, mainly in mouth orientation, size and orientation of fins, and thickness of the caudal peduncle. As between population differentiation was lower in the wild than differentiation between pond-raised versus wild fish, we suggest the narrow ecological niche and intense interspecific competition in rock habitats is responsible for consistent shape similarity, even among long-term isolated populations.


Assuntos
Animais Selvagens/anatomia & histologia , Animais Selvagens/classificação , Ciclídeos/anatomia & histologia , Ciclídeos/classificação , Água Doce , Variação Genética , Fenótipo , Animais , Animais Selvagens/genética , Feminino , Masculino , Repetições de Microssatélites/genética
6.
J Biomol Tech ; 21(1): 25-8, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20357979

RESUMO

Laser-capture microdissection (LCM) enables the selection of a specific and pure cell population from a heterogenous tissue such as tumors. Activity-based protein profiling/profile (ABPP) is a chemical technology using enzyme-specific active site-directed probes to read out the functional state of many enzymes directly in any proteome. The aim of this work was to assess the compatibility of LCM with downstream ABPP for serine hydrolase (SH) in human lung adenocarcinoma. Fresh frozen lung adenocarcinoma tissue was stained with hematoxylin, toluidine blue, or methyl green (MG). Proteome from stained tissue was labeled further with SH-directed probes, and ABPPs were determined on a one-dimensional gel-based approach. This allowed us to assess the impact of staining procedures on their ABPPs. The effect of the LCM process on ABPPs was assessed furthermore using MG-stained lung adenocarcinoma tissue. The staining procedures led to strong changes in ABPPs. However, MG staining seemed the most compatible with downstream ABPP. MG-stained, laser-captured, microdissected tissue showed additional change in profiles as a result of the denaturing property of extraction buffer but not to the microdissection process itself. LCM staining procedures but not microdissection per se interfered with downstream ABPP and led to a strong change in ABPPs of SHs in human lung adenocarcinoma.


Assuntos
Adenocarcinoma/enzimologia , Lasers , Neoplasias Pulmonares/enzimologia , Microdissecção/métodos , Análise Serial de Proteínas/métodos , Serina Proteases/metabolismo , Eletroforese em Gel de Poliacrilamida , Humanos , Coloração e Rotulagem
7.
Transplantation ; 88(4): 478-85, 2009 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-19696630

RESUMO

BACKGROUND: Systemic inhibition of serum CD26/dipeptidylpeptidase (DPP IV) enzymatic activity abrogated acute rejection of pulmonary allografts, whereas organ-specific inhibition ameliorated ischemia/reperfusion injury in syngeneic transplants. Here, we analyze the effect of allograft-specific inhibitor preconditioning on acute rejection in the presence of cyclosporine-based immunosuppressive therapy. METHODS: Orthotopic left single lung transplantation (Tx) in rats (LBNF1 to LEWIS). Control (n=5) grafts were flushed with Perfadex alone, whereas treated (n=5) transplants were perfused with Perfadex and AB192, a specific inhibitor of CD26/DPP IV enzymatic activity. All recipients were treated with 2.5 mg of cyclosporine A/kg per day subcutaneously after Tx. Recipients were sacrificed at day 5 after Tx, and oxygenation capacity was measured. In addition, staining for vasoactive intestinal peptide (VIP) and proliferating cell nuclear antigen (PCNA) at explantation (VIP) and at day 5 (VIP, PCNA) was performed with determination of protein levels for PCNA and mRNA for VIP. RESULTS: Grafts from treated versus controls showed significantly increased oxygenation capacity (P<.008), correlating with significantly less acute rejection (P<.02). PCNA staining and protein expression were significantly lower in perivascular and bronchial epithelial cells (P=.001) in treated versus controls. There was significantly higher staining for VIP at the time of Tx in alveolar macrophages in treated versus controls (P=.001), which was seen up to day 5 post-Tx in both macrophages and respiratory epithelium (P=.001) with elevated mRNA expression for VIP in treated animals. CONCLUSION: Perfusion with a specific inhibitor of CD26/DPP IV enzymatic activity was associated with sustained preservation of pulmonary VIP levels, correlating with an amelioration of the acute rejection cascade.


Assuntos
Inibidores da Dipeptidil Peptidase IV , Rejeição de Enxerto/prevenção & controle , Transplante de Pulmão/imunologia , Doença Aguda , Animais , Rejeição de Enxerto/enzimologia , Rejeição de Enxerto/imunologia , Transplante de Pulmão/patologia , Transplante de Pulmão/fisiologia , Masculino , Organofosfonatos/farmacologia , Peroxidase/metabolismo , Antígeno Nuclear de Célula em Proliferação/metabolismo , Prolina/análogos & derivados , Prolina/farmacologia , Inibidores de Proteases/farmacologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Endogâmicos BN , Ratos Endogâmicos Lew , Condicionamento Pré-Transplante/métodos , Transplante Homólogo , Peptídeo Intestinal Vasoativo/genética , Peptídeo Intestinal Vasoativo/metabolismo
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