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1.
Psychoneuroendocrinology ; 168: 107114, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38991306

RESUMO

OBJECTIVE: To synthesise the literature examining the autonomic nervous system (ANS) and cortisol responses to an acute stressor following total sleep deprivation (TSD) in healthy adult subjects. METHODS: We conducted a systematic review (CRD42022293857) following the latest PRISMA statement. We searched Medline (via Ovid), Embase (via Ovid), PsycINFO (via Ovid), CINAHL complete and Scopus databases, without year restriction, using search terms related to "sleep deprivation", "stress", "autonomic nervous system" and "cortisol". Two independent team members used pre-defined inclusion/exclusion criteria to assess eligibility and extract data. We used RoB 2 to assess the risk of bias in randomised controlled trials, and ROBINS-I for non-randomised studies. RESULTS: Sixteen studies, with 581 participants (mean age = 29 ± 12 years), were eligible for inclusion in the descriptive syntheses. Half of the studies (n = 8) were conducted in the United States of America. The most commonly used study designs were randomised crossover studies (n = 7) and randomised controlled trials (n = 5). Most studies used a single night of TSD (n = 13) which was followed by a psychological (n = 6), physical (n = 5) or psychological and physical (n = 5) acute stressor event. Heart rate (n = 8), cortisol (n = 7) and blood pressure (n =6) were the most reported outcomes, while only a single study used forearm vascular conductance and forearm blood flow. Ten studies found that TSD changed, at least, one marker of ANS or cortisol response. TSD compared with a sleep control condition increased cortisol level (n=1), systolic blood pressure (n=3), diastolic blood pressure (n=2), mean arterial pressure (n=1), and electrodermal activity (n=1) after acute stress. Also, compared with a sleep control, TSD blunted cortisol (n=2), heart rate (n=1) and systolic blood pressure (n=2) responses after acute stress. However, TSD did not change ANS or cortisol responses to acute stressors in 73 % of the total reported outcomes. Furthermore, 10 RCT studies (62.5 %) were assigned as "some concerns" and two RCT studies (12.5 %) were attributed "high" risk of bias. Additionally, one non-randomised trial was classified as "moderate" and three non-randomised trials as "serious" risk of bias. CONCLUSION: The markers of ANS and cortisol responses to acute stress after TSD in healthy individuals reveal a scarcity of consistent evidence. The included studies present enough evidence that TSD induces either blunted or exaggerated ANS or cortisol responses to laboratory stresses supporting the "bidirectional multi-system reactivity hypothesis.". It appears that a comprehensive understanding of this phenomenon still lacks robust evidence, and further research is needed to clarify these relationships.

2.
Mol Phylogenet Evol ; 141: 106627, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31539606

RESUMO

The advent of next-generation sequencing allows researchers to use large-scale datasets for species delimitation analyses, yet one can envision an inflection point where the added accuracy of including more loci does not offset the increased computational burden. One alternative to including all loci could be to prioritize the analysis of loci for which there is an expectation of high informativeness. Here, we explore the issue of species delimitation and locus selection with montane species from two anuran genera that have been isolated in sky islands across the southern Brazilian Atlantic Forest: Melanophryniscus (Bufonidae) and Brachycephalus (Brachycephalidae). To delimit species, we obtained genetic data using target enrichment of ultraconserved elements from 32 populations (13 for Melanophryniscus and 19 for Brachycephalus), and we were able to create datasets that included over 800 loci with no missing data. We ranked loci according to their number of parsimony-informative sites, and we performed species delimitation analyses using BPP with the most informative 10, 20, 40, 80, 160, 320, and 640 loci. We identified three types of phylogenetic node: nodes with either consistently high or low support regardless of the number of loci or their informativeness and nodes that were initially poorly supported where support became stronger as we included more data. When viewed across all sensitivity analyses, our results suggest that the current species richness in both genera is likely underestimated. In addition, our results show the effects of different sampling strategies on species delimitation using phylogenomic datasets.


Assuntos
Anuros/classificação , Anuros/genética , Florestas , Filogenia , Animais , Oceano Atlântico , Brasil , Filogeografia , Especificidade da Espécie
3.
Mater Sci Eng C Mater Biol Appl ; 100: 411-423, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30948077

RESUMO

The low interaction between ultra high molecular weight polyethylene (UHMWPE) and hydroxyapatite (HA) has been one of the problems that results in a composite material with low mechanical and tribological performance due to the formation of agglomerates and microstructural defects. These properties affect the quality of the material when used for total joint implants and other applications in hard tissue engineering. This study investigated the effect of the addition of organophilic bentonite (BO) into the interface HA and UHMWPE. The composite was prepared by wet milling in a planetary mill and then by compression molding. The composites samples were characterized by XRD, FTIR, SEM and DSC. The tensile and tribological mechanical properties were also evaluated. Furthermore, in vitro degradation using simulated blood fluid (SBF) and hemocompatibility was performed. The results suggest that the addition of 10 wt% of organophilic bentonite improved the interface between the UHMWPE and HA by exfoliation/intercalation, presenting the best results of modulus of elasticity, tensile strength, coefficient of friction and rate of wear. The composite UHMWPE/HA/BO-10 wt% presented low water absorption and induced the growth of apatite crystals on its surface. Additionally, its hemocompatibility index is within normal limits and induced a low adhesion and agglomeration of platelets in contact with human blood, evidencing that the UHMWPE/HA/BO-10 wt% composite is promising for application in bone tissue engineering.


Assuntos
Bentonita/química , Materiais Biocompatíveis/química , Sangue , Durapatita/química , Teste de Materiais , Polietilenos/química , Animais , Varredura Diferencial de Calorimetria , Camundongos , Adesividade Plaquetária , Resistência à Tração
4.
PeerJ ; 6: e5683, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30310742

RESUMO

A new miniaturized frog of the genus Brachycephalus (Anura: Brachycephalidae) is described from Morro Santo Anjo in the municipality of Massaranduba, Santa Catarina, southern Brazil. Specimens were collected from the leaf litter between 470 and 540 above sea level. The new species is distinguished from all its congeners by the combination of the following characters: (1) body robust and bufoniform; (2) size snout-vent length 9.9-11.7 mm for males and 10.0-12.9 mm for females; (3) smooth dorsum; (4) general color (in life) orange with white dots and stripe in the middle of the head and along its vertebral column; (5) iris completely black; (6) advertisement call composed of note groups; (7) isolated notes with 1-3 pulses; and (8) short isolated notes (0.002-0.027 s). An estimate of the male density of the new species is also presented. Phylogenetic information indicates that the new species is part of the southernmost clade of Brachycephalus, which includes Brachycephalus fuscolineatus, B. albolineatus, and B. boticario. The severe anthropogenic impacts in and around the type locality indicate that immediate actions should be taken to ensure the long-term preservation of the new species.

5.
J Sep Sci ; 41(24): 4449-4457, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30367711

RESUMO

We demonstrated that the porous structure and the reactivity of the epoxy group in the poly glycidyl methacrylate-co-ethylene dimethacrylate monolith can be a platform for the development of separation and extraction methods based on sequential injection analysis. The epoxy group was functionalized to produce monoliths affording complexing and ion exchange properties. Derivatization with iminodiacetate and sodium sulfite produced weak and strong cation exchangers, respectively. Derivatization with ethylenediamine produced a weak anion exchanger, and the treatment of the ethylenediamine-modified monolith with chloroacetate produced another weak cation exchanger. All the monoliths also worked as chelating sorbents. The columns were prepared inside 50 × 2.01 mm id fused-silica lined stainless steel tubing and exhibited permeabilities between 0.76 and 4.92 × 10-13 m2 , which enabled the application of flow rates between 5 and 15 µL/s by the syringe pumps used in sequential injection analyzers. These columns separated proteins by cation or anion exchange in a sequential injection chromatograph in both synthetic mixtures and in egg white. Additionally, the online solid-phase extraction of copper ions was demonstrated in a sequential injection analyzer with the same columns. Postcolumn derivatization with ethylenediamine and spectrophotometric detection was used for the copper detection.


Assuntos
Cobre/análise , Etilenoglicóis/química , Análise de Injeção de Fluxo , Metacrilatos/química , Extração em Fase Sólida , Adsorção , Tamanho da Partícula , Porosidade , Propriedades de Superfície
6.
Front Physiol ; 9: 843, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30034346

RESUMO

Sports and exercise today are popular for both amateurs and athletes. However, we continue to seek the best ways to analyze best athlete performances and develop specific tools that may help scientists and people in general to analyze athletic achievement. Standard statistics and cause-and-effect research, when applied in isolation, typically do not answer most scientific questions. The human body is a complex holistic system exchanging data during activities, as has been shown in the emerging field of network physiology. However, the literature lacks studies regarding sports performance, running, exercise, and more specifically, sprinter athletes analyzed mathematically through complex network modeling. Here, we propose complex models to jointly analyze distinct tests and variables from track sprinter athletes in an untargeted manner. Through complex propositions, we have incorporated mathematical and computational modeling to analyze anthropometric, biomechanics, and physiological interactions in running exercise conditions. Exercise testing associated with complex network and mathematical outputs make it possible to identify which responses may be critical during running. The physiological basis, aerobic, and biomechanics variables together may play a crucial role in performance. Coaches, trainers, and runners can focus on improving specific outputs that together help toward individuals' goals. Moreover, our type of analysis can inspire the study and analysis of other complex sport scenarios.

7.
Zootaxa ; 4350(3): 587-589, 2017 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-29245546

RESUMO

Brachycephalus is a fascinating genus of miniaturized frogs endemic to the Brazilian Atlantic Forest (Bornschein et al. 2016a). Given the many new species that have been recently discovered (20 species over the past 10 years [Frost 2017]) and their often microendemic distribution (see Bornschein et al. 2016a), there has been an increasing awareness about the need for more extensive field work to locate additional new species, to describe their geographical distributions, and to devise comprehensive efforts to ensure their conservation. In a recent correspondence in Zootaxa, Condez et al. (2017) singled out nine of those new species that have been described by our research group (Ribeiro et al. 2015; Pie & Ribeiro 2015; Bornschein et al. 2016b); two additional species (Ribeiro et al. 2017) were described after their paper was published. According to Condez et al. (2017), our species descriptions included "inadequate diagnoses, which lacked indispensable information for any further comparisons among species" (p. 395). Herein, we explore the extent to which their arguments would undermine the validity of those species.


Assuntos
Anuros , Animais , Brasil , Florestas
8.
PeerJ ; 5: e3603, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28761788

RESUMO

We describe two new species of miniaturized toadlet in the B. pernix group of Brachycephalus (Anura: Brachycephalidae) from the Atlantic Forest of the state of Paraná, southern Brazil. The first new species is distinguished from all congeners by the pale red coloration from the head to the pelvic region, with sides of the body and thighs dorsally yellowish green. It is known only from the type locality in a cloud forest at altitudes ranging between 1,144-1,228 m a.s.l. The second species, although more closely related to B. izecksohni, is morphologically similar to B. brunneus in its overall brown coloration, but distinct from that species in the color of the iris (black with conspicuous golden spots, instead of entirely black). It was found on three mountains, at altitudes between 1,095-1,320 m a.s.l., and in vegetation types including cloud forest, montane forest, and secondary forest. The two new species exhibit neither vertebral fusions nor osteoderms, but one has both a distinct neopalatine and well-developed odontoids on the maxillae. We discuss the conservation status of both species.

9.
Gene ; 628: 194-199, 2017 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-28720533

RESUMO

Melanophryniscus is a bufonid frog genus with a broad geographic distribution over southeastern South America. In recent years, several new species of Melanophryniscus have been discovered in southern Brazil showing a distinctive life-history strategy for the genus - breeding in phytotelmata - as well as a strong association with high-altitude regions. In this study, we use mitogenomic data to infer the phylogenetic relationships among diurnal, phytotelm-breeding Melanophryniscus and to determine the timing of their divergence. We obtained the mitochondrial genomes (not including the control region) for eight individuals of Melanophryniscus representing all three described species (M. alipioi, M. milanoi, and M. xanthostomus), as well as some recently-discovered and potentially new species. Gene order was conserved in all species and corresponded to the general order found in bufonids. Although the phylogenetic relationships among the studied species was poorly supported, dating confirmed that they diverged during the Pleistocene, suggesting that phytotelm breeding could have arisen during drier periods in the glacial/interglacial cycles due to a decrease in the availability of permanent streams or ephemeral/temporary streams or ponds in which Melanophryniscus species commonly breed.


Assuntos
Bufonidae/classificação , Bufonidae/genética , Genoma Mitocondrial , Filogenia , Animais , Cruzamento , Ordem dos Genes , Genes Mitocondriais
10.
PeerJ ; 4: e2629, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27812425

RESUMO

A new species of Brachycephalus (Anura: Brachycephalidae) is described from the Atlantic Forest of northeastern state of Santa Catarina, southern Brazil. Nine specimens (eight adults and a juvenile) were collected from the leaf litter of montane forests 790-835 m above sea level (a.s.l.). The new species is a member of the pernix group by its bufoniform shape and the absence of dermal co-ossification and is distinguished from all its congeners by a combination of its general coloration (dorsal region of head, dorsum, legs, arms, and flanks light, brownish green to dark, olive green, with darker region in the middle of the dorsum and a white line along the vertebral column in most specimens) and by its smooth dorsum. The geographical distribution of the new species is highly reduced (extent of occurrence estimated as 25.04 ha, or possibly 34.37 ha). In addition, its habitat has experienced some level of degradation, raising concerns about the future conservation of the species. Preliminary density estimates suggest one calling individual every 3-4 m2 at 815-835 m a.s.l. and every 100 m2 at 790 m a.s.l. Together with the recently described B. boticario and B. fuscolineatus, the new species is among the southernmost species of Brachycephalus known to date.

11.
PeerJ ; 4: e2490, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27761312

RESUMO

Mountains of the Brazilian Atlantic Forest can act as islands of cold and wet climate, leading to the isolation and speciation of species with low dispersal capacity, such as the toadlet species of the genus Brachycephalus. This genus is composed primarily by diurnal species, with miniaturized body sizes (<2.5 cm), inhabiting microhabitats in the leaf litter of montane forests. Still, little is known about the geographical distribution, altitudinal range, and ecological limits of most Brachycephalus species. In this study, we review the available data on the geographical and altitudinal distribution of Brachycephalus based on occurrence records compiled from literature and museums, both for the genus as a whole and separately for the three recently proposed groups of species (ephippium, didactylus, and pernix). The final ensemble dataset comprised 333 records, 120 localities, 28 described species, and six undescribed ones. Species were recorded in six relief units, the richest of which being the Serra do Mar, with 30 species. When the Serra do Mar is subdivided into three subunits, Northern, Central and Southern Serra do Mar, the number of species increase from north to the south, with records of six, nine, and 16 species, respectively. We were able to estimate the extent of occurrence of nearly half of the described species, and the resulting estimates indicate that many of them show remarkably small ranges, some of which less than 50 ha. Brachycephalus species are present from sea level to roughly 1,900 m a.s.l., with the highest richness being found between 751 and 1,000 m a.s.l. (21 spp.). The species with the broadest altitudinal range were B. didactylus (1,075 m) and Brachycephalus sp. 1 (1,035 m), both in the didactylus group, and B. ephippium (1,050 m), of the ephippium group. The broadest altitudinal amplitude for species of the pernix group was recorded for B. brunneus (535 m). The lowest altitudinal records for the pernix group were at 845 m a.s.l. in the state of Paraná and at 455 m a.s.l. in the state of Santa Catarina. The altitudinal occurrence in the pernixspecies group seems to decrease southward. Syntopy between species is also reviewed.

12.
Mol Phylogenet Evol ; 100: 345-360, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27129900

RESUMO

The Brazilian Atlantic Forest (BAF) is recognized as one of the world's biodiversity hotspots, with even more species per unit of area than the Amazon, however the mechanisms that led to such astonishing diversity are yet to be fully understood. In this study, we investigate the diversification of two co-distributed frog genera associated with montane areas of southern BAF: Melanophryniscus (Bufonidae) and Brachycephalus (Brachycephalidae). Species delimitation methods using mitochondrial and nuclear loci supported the existence of a remarkable number of highly endemic species in each genus, most of which occupy only one or a few adjacent mountaintops. Their timing of diversification was highly congruent, supporting recent speciation events within the past 600 thousand years. Extended Bayesian skyline plots indicate that most populations have remained relatively stable in size across the evolutionary past, with recent growth after 0.15My, suggesting that the drastic changes found in previous studies on lowland frog species were not shared by these montane taxa. These results are consistent with the existence of a montane refugium in southern BAF, allowing species persistence through the climatic shifts experienced along the BAF during the Quaternary.


Assuntos
Bufonidae/genética , Proteínas de Anfíbios/genética , Distribuição Animal , Animais , Teorema de Bayes , Brasil , Bufonidae/classificação , Mudança Climática , Florestas , Especiação Genética , Tipagem de Sequências Multilocus , Filogenia , Filogeografia
14.
PLoS One ; 10(12): e0142791, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26630281

RESUMO

Three new species of Melanophryniscus are described from the Serra do Mar mountain range of the state of Santa Catarina, southern Brazil. All species are found at intermediate to high altitudes and share phytotelm-breeding as their reproductive strategy. The new species are distinguished from other phytotelm-breeding Melanophryniscus based on different combinations of the following traits: snout-vent length, presence of white and/or yellow spots on forearms, mouth, belly and cloaca, pattern and arrangement of warts, and presence and number of corneous spines. The discovery of these species in a rather restricted geographical area suggests that the diversity of phytotelm-breeding species of Melanophryniscus might be severely underestimated. The conservation status of these species is of particular concern, given that one of them is at risk of extinction not only due to its restricted habitat, but also because of anthropogenic disturbances.


Assuntos
Cruzamento , Bufonidae/anatomia & histologia , Bufonidae/classificação , Ecossistema , Reprodução/fisiologia , Animais , Brasil , Bufonidae/fisiologia , Geografia , Filogenia , Floresta Úmida , Especificidade da Espécie
15.
PeerJ ; 3: e1179, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26339556

RESUMO

A new miniaturized toadled of the genus Brachycephalus (Anura: Brachycephalidae) is described from Serra do Quiriri in the municipality of Campo Alegre, Santa Catarina, southern Brazil. Specimens were collected from the leaf litter between from 1,263 and 1,318 m above sea level. The new species is distinguished from all its congeners by the combination of the following characters: snout-vent length 9.9-13.1 mm; skin on head and dorsum without dermal co-ossification; snout mucronate in dorsal view; dorsum rugose; general color brown, with a narrow orange vertebral stripe. The region where the new species is located is also shared with other endemic anuran species and has experienced strong anthropogenic impacts,suggesting that immediate actions should be taken to ensure their long-term preservation.

16.
PeerJ ; 3: e1011, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26056613

RESUMO

Brachycephalus (Anura: Brachycephalidae) is a remarkable genus of miniaturized frogs of the Brazilian Atlantic Rainforest. Many of its species are highly endemic to cloud forests, being found only on one or a few mountaintops. Such level of microendemism might be caused by their climatic tolerance to a narrow set of environmental conditions found only in montane regions. This restriction severely limits the chance of discovery of new species, given the difficulty of exploring these inaccessible habitats. Following extensive fieldwork in montane areas of the southern portion of the Atlantic Rainforest, in this study we describe seven new species of Brachycephalus from the states of Paraná and Santa Catarina, southern Brazil. These species can be distinguished from one another based on coloration and the level of rugosity of the skin in different parts of their body. These discoveries increase considerably the number of described species of Brachycephalus in southern Brazil.

17.
Proc Biol Sci ; 281(1792)2014 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-25122231

RESUMO

Phylogeographic endemism, the degree to which the history of recently evolved lineages is spatially restricted, reflects fundamental evolutionary processes such as cryptic divergence, adaptation and biological responses to environmental heterogeneity. Attempts to explain the extraordinary diversity of the tropics, which often includes deep phylogeographic structure, frequently invoke interactions of climate variability across space, time and topography. To evaluate historical versus contemporary drivers of phylogeographic endemism in a tropical system, we analyse the effects of current and past climatic variation on the genetic diversity of 25 vertebrates in the Brazilian Atlantic rainforest. We identify two divergent bioclimatic domains within the forest and high turnover around the Rio Doce. Independent modelling of these domains demonstrates that endemism patterns are subject to different climatic drivers. Past climate dynamics, specifically areas of relative stability, predict phylogeographic endemism in the north. Conversely, contemporary climatic heterogeneity better explains endemism in the south. These results accord with recent speleothem and fossil pollen studies, suggesting that climatic variability through the last 250 kyr impacted the northern and the southern forests differently. Incorporating sub-regional differences in climate dynamics will enhance our ability to understand those processes shaping high phylogeographic and species endemism, in the Neotropics and beyond.


Assuntos
Biodiversidade , Clima , Variação Genética/genética , Filogeografia , Vertebrados/genética , Animais , Sequência de Bases , Evolução Biológica , Brasil , Dados de Sequência Molecular , Dinâmica Populacional
18.
BMC Cancer ; 9: 212, 2009 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-19563658

RESUMO

BACKGROUND: Adenosquamous carcinoma of the uterine cervix is an infrequent but aggressive subtype of cervical cancer. A better understanding of its biological behaviour is warranted to define more accurate prognosis and therapeutic targets. Currently, the blockage of receptor tyrosine kinase (RTKs) activity is an efficient therapeutic strategy for many different cancers. The objective of this study was to investigate EGFR, PDGFRA and VEGFR2 RTKs overexpression and activating gene mutations in a cohort of 30 adenosquamous carcinomas of the uterine cervix. METHODS: EGFR, PDGFRA and VEGFR2 immunohistochemistry was performed in all samples, followed by DNA isolation from the gross macroscopically dissection of the neoplastic area. Screening for EGFR (exons 18-21) and PDGFRA (exons 12, 14 and 18) mutations was done by PCR--single-strand conformational polymorphism (PCR-SSCP). RESULTS: Despite the presence of EGFR immunohistochemical positive reactions in 43% (13/30) of the samples, no EGFR activating mutations in the hotspot region (exons 18-21) were identified. A silent base substitution (CAG>CAA) in EGFR exon 20 at codon 787 (Q787Q) was found in 17 cases (56%). All PDGFRA immunohistochemical reactions were positive and consistently observed in the stromal component, staining fibroblasts and endothelial cells, as well as in the cytoplasm of malignant cells. No activating PDGFRA mutations were found, yet, several silent mutations were observed, such as a base substitution in exon 12 (CCA>CCG) at codon 567 (P567P) in 9 cases and in exon 18 (GTC>GTT) at codon 824 (V824V) in 4 cases. We also observed the presence of base substitutions in intron 14 (IVS14+3G>A and IVS14+49G>A) in two different cases, and in intron 18 (IVS18-50insA) in 4 cases. VEGFR2 positivity was observed in 22 of 30 cases (73.3%), and was significantly associated with lack of metastasis (p=0.038). CONCLUSION: This is the most extensive analysis of EGFR, PDGFRA and VEGFR2 in cervical adenosquamous carcinomas. Despite the absence of EGFR and PDGFRA activating mutations, the presence of overexpression of these three important therapeutic targets in a subset of cases may be important in predicting the sensitivity of adenosquamous carcinoma to specific anti-RTKs drugs.


Assuntos
Carcinoma/genética , Receptores ErbB/genética , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/genética , Neoplasias do Colo do Útero/genética , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/genética , Adulto , Idoso , Estudos de Coortes , Feminino , Humanos , Imuno-Histoquímica/métodos , Metástase Linfática , Pessoa de Meia-Idade , Polimorfismo Conformacional de Fita Simples , Estudos Retrospectivos
19.
Gynecol Oncol ; 111(2): 350-5, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18708242

RESUMO

OBJECTIVES: Uterine adenosquamous carcinoma (ASC) is an uncommon, yet, one of the most aggressive cervical cancer subtype. The successful treatment of some tumors, such as gastrointestinal stromal tumors (GISTs), by anti-KIT inhibitors fosters the study of this receptor tyrosine kinase in other malignancies. In the present study, we intended to molecularly characterize KIT in ASC. METHODS: In a series of 30 cases, we studied KIT (CD117), KIT phosphorylated/activated form, as well as KIT ligand, stem cell factor (SCF), by immunohistochemistry. We further screened for KIT hotspot mutations (exon 9, 11, 13 and 17) by PCR-SSCP and for KIT gene amplification by Quantitative real-time PCR in CD117 positive cases. RESULTS: We observed CD117 expression in approximately 13% of cases, with approximately 7% co-expressing SCF, which resulted in KIT phosphorylation/activation. No KIT activating mutations or gene amplification were found, despite the presence of 4q aneuploidy in one case. CONCLUSIONS: This is the first study assessing KIT activation and molecular alterations in a large series of rare ASC. Our findings showed the absence of KIT molecular alterations and suggested the presence of KIT activation in a small proportion of cases through KIT/SCF co-expression.


Assuntos
Carcinoma Adenoescamoso/enzimologia , Proteínas Proto-Oncogênicas c-kit/metabolismo , Fator de Células-Tronco/metabolismo , Neoplasias do Colo do Útero/enzimologia , Adulto , Idoso , Carcinoma Adenoescamoso/genética , Carcinoma Adenoescamoso/patologia , Ativação Enzimática , Feminino , Amplificação de Genes , Humanos , Imuno-Histoquímica , Pessoa de Meia-Idade , Mutação , Fosforilação , Reação em Cadeia da Polimerase , Polimorfismo Conformacional de Fita Simples , Proteínas Proto-Oncogênicas c-kit/biossíntese , Proteínas Proto-Oncogênicas c-kit/genética , Fator de Células-Tronco/biossíntese , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/patologia , Adulto Jovem
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