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1.
An Acad Bras Cienc ; 91(3): e20180209, 2019 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-31482993

RESUMO

Twig girdlers have a short adult life and a long larval stage (up to one year in some species). This fact, together with lack of morphological traits to identify the species from the larval stage, poses obstacles for the taxonomic identification and characterization of the many twig girdlers found in the wild. To solve this matter, Random Amplified Polymorphic DNA (RAPD) molecular markers have been applied to identify some insect species and to determine species boundaries. The aim of this study was to identify three species of Oncideres using the RAPD technique. Adults and larvae of O. saga, O. ocularis and O. ulcerosa were collected in Minas Gerais, Brazil. Two RAPD primers were used (OPA-05 and OPB-13), which produced different electrophoretic profiles that were used to construct a UPGMA phenogram. Three groups identified in the analyses accurately separated the three species, based on individuals in two different stages of development (adults and larvae): I: O. saga, II: O. ulcerosa, and III: O. ocularis. Molecular markers, such as RAPD, are valuable tools that help taxonomists in species identification.


Assuntos
Besouros/genética , Marcadores Genéticos/genética , Animais , Besouros/classificação , Técnica de Amplificação ao Acaso de DNA Polimórfico , Especificidade da Espécie
2.
J Agric Food Chem ; 67(38): 10774-10781, 2019 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-31479258

RESUMO

The released milk N-glycome has been found to possess antipathogenic activity. Natively, they are covalently linked onto proteins. Whether the conjugated N-glycans still have antipathogenic properties and how the glycosylation influences the antipathogenic activity of proteins remain unclear. Herein, we compared the quantitative differences of milk protein N-glycosylation and the antilisterial differences of native milk proteins, released N-glycan pools, and deglycosylated proteins between human and bovine milk. N-glycosylation exhibited to be quantitatively species-specific. The entire growth inhibitory activity and the majority of the antiadhesive activity against Listeria monocytogenes of milk whey proteins, although not as high as the released N-glycans, are attributed to N-glycosylation. Moreover, all N-glycan-bearing samples from human milk showed better growth inhibitory activities than those from bovine milk. Generally, N-glycosylation significantly contributes to the antilisterial function of milk proteins and to the functional differences between species. This gives novel insights into the role of these glycoconjugates in nature.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Listeria monocytogenes/efeitos dos fármacos , Proteínas do Leite/química , Proteínas do Leite/farmacologia , Leite Humano/química , Animais , Aderência Bacteriana/efeitos dos fármacos , Células CACO-2 , Bovinos , Glicosilação , Humanos , Listeria monocytogenes/crescimento & desenvolvimento , Listeria monocytogenes/fisiologia , Polissacarídeos/química , Especificidade da Espécie
3.
Adv Exp Med Biol ; 1200: 243-273, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31471800

RESUMO

Asian (Elephas maximus) and African (Loxodonta africana) elephants serve as important keystone, umbrella and flagship species. Despite that, population numbers are declining, due mainly to poaching and habitat destruction. Understanding reproductive mechanisms is vital to effective management, particularly insurance populations in captivity, and to that end, long-term biological databases are key to understanding how intrinsic and extrinsic factors affect reproductive function at individual and population levels. Through decades of hormonal and ultrasonographic monitoring, many unique aspects of zoo elephant reproduction have been identified, including differences in luteal steroidogenic activity, follicular maturation, pituitary gonadotropin secretion, fetal development and reproductive tract anatomy. Reproductive problems also hamper captive propagation efforts, particularly those related to abnormal or lack of ovarian cyclicity. Recent large-scale, multi-institutional studies and use of epidemiological approaches have identified factors important for good welfare and reproduction, which include enrichment, feeding diversity, good elephant-keeper relations, social compatibility, exercise, and not being obese. There are notable differences in reproductive mechanisms between Asian and African elephants, as well as the factors that influence reproduction and welfare, suggesting species-targeted management approaches are needed to maximize fitness. In the first edition, we discussed reproductive function in male and female elephants. Since then, a number of significant advances have been made primarily in female elephants, which will be the focus of this updated review.


Assuntos
Conservação dos Recursos Naturais , Elefantes/classificação , Elefantes/fisiologia , Reprodução , Animais , Feminino , Masculino , Especificidade da Espécie
4.
An Acad Bras Cienc ; 91(suppl 2): e20180614, 2019 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-31411248

RESUMO

Discoveries in Carnian-aged rocks are establishing a rich and diverse dinosaurian fauna at the so-called 'dawn of the age of dinosaurs' in the Late Triassic of Western Gondwana. Accordingly, Brazilian strata from the Candelária Sequence have contributed extensively to this trend. Here, we present a new dinosaurian specimen (CAPPA/UFSM 0200) from this geological unit. The material was collected at a fossiliferous site that had no previous record of dinosaurs. Our specimen comprises a single ilium, which we describe in detail. Its anatomy is consistent with Carnian sauropodomorph dinosaurs, but differs from coeval specimens by several features, although we do not discard the possibility of these features being the result of intraspecific variation. In part of our phylogenetic investigation, CAPPA/UFSM 0200 was recovered within Saturnaliinae, a group comprised of Carnian sauropodomorphs from South America. However, based on examination of better-sampled coeval taxa, a character (a strong rugosity in the ilium) supporting this less inclusive position might be related to intraspecific variation and so, should be carefully considered. This study increases the distribution of dinosaur remains in fossiliferous units from southern Brazil and adds to the discussion regarding intraspecific variation and its implications in the phylogeny of early dinosaurs.


Assuntos
Dinossauros/anatomia & histologia , Ílio/anatomia & histologia , Animais , Evolução Biológica , Brasil , Dinossauros/classificação , Filogenia , Especificidade da Espécie
5.
An Acad Bras Cienc ; 91(3): e20180428, 2019 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-31411256

RESUMO

This study aimed to know the patterns of spatial distribution of Anastrepha spp. and establish a criterion for determining the appropriate time for pest control. For this, 90 McPhail traps were used as Sampling Units (SU) divided into three commercial orchards of Novo Milênio guava with a total area of 14 ha. Traps were interspersed between the rows of plants, systematically in the orchards, hung and baited with 5% hydrolyzed corn protein with weekly collections. We caught 8,170 Anastrepha spp. in 840 SU. The mean infestation index was compared to the three types of distribution: random, uniform, aggregate, and fit by the theoretical frequency distributions of Poisson, negative binomial and positive binomial. The populations of Anastrepha presented aggregate distribution according to the mean variance method (I), tested by distance from randomness. The economic damage risk potential of Anastrepha spp. was associated with the aggregate distribution behavior. The most appropriate moment for the use of control techniques is when reaching 20 flies by the negative binomial. On the other hand, number of fruit fly adults per trap per day (FTD), underestimates population index, which will allow population growth, leading to risk of crop production loss.


Assuntos
Distribuição Animal , Tephritidae , Animais , Distribuição Binomial , Brasil , Produtos Agrícolas , Psidium , Especificidade da Espécie
6.
Life Sci ; 234: 116770, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31421085

RESUMO

Aim Licoricidin has multiple pharmacological activities. The present study was designed to investigate the permeability and pharmacokinetic behavior of licoricidin using in vitro models. MATERIAL AND METHODS: First, human liver microsomes and recombinant human supersomes were used to investigate the interactions between metabolic enzymes and licoricidin. In addition, rat, minipig, rabbit, dog, monkey, and human liver microsomes were used to determine metabolic differences among species. The parallel artificial membrane permeability assay (PAMPA) was used to explore licoricidin permeability behavior. KEY FINDINGS: At 100 µM, licoricidin strongly inhibited CYP2C9, CYP2C19, CYP3A4, UGT1A3, UGT1A6, UGT1A7, UGT1A8, UGT1A9, UGT2B4, UGT2B7, UGT2B15, and UGT2B17. Licoricidin metabolism exhibited considerable differences among species; dog, pig, and rat liver microsomes showed higher metabolic capacity than the other species. Seven licoricidin metabolites were identified by liquid chromatography-tandem mass spectrometry, and hydration and hydroxylation were the major metabolic pathways. The PAMPA permeability of licoricidin was moderate at both pH 4.0 and 7.4. SIGNIFICANCE: The present study will support further pharmacological or toxicological research on licoricidin.


Assuntos
Benzopiranos/metabolismo , Benzopiranos/farmacocinética , Animais , Inibidores das Enzimas do Citocromo P-450/metabolismo , Inibidores das Enzimas do Citocromo P-450/farmacocinética , Sistema Enzimático do Citocromo P-450/metabolismo , Cães , Glucuronosiltransferase/antagonistas & inibidores , Glucuronosiltransferase/metabolismo , Haplorrinos , Humanos , Redes e Vias Metabólicas , Microssomos Hepáticos/metabolismo , Permeabilidade , Coelhos , Ratos , Especificidade da Espécie , Suínos , Porco Miniatura
7.
Plant Dis ; 103(10): 2624-2633, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31397632

RESUMO

Brown spot disease caused by Colletotrichum species was found on leaves of mulberry (Morus alba L.) in Dujiangyan, Sichuan Province, China. Fungal isolates from leaf lesions were identified as six Colletotrichum species based on morphological characteristics and DNA analysis of the combined sequences ITS, GAPDH, ACT, CHS-1, TUB2, and GS. These included Colletotrichum fioriniae, C. fructicola, C. cliviae, C. karstii, C. kahawae subsp. ciggaro, and C. brevisporum. Results showed that the most important causal agent of mulberry anthracnose was C. fioriniae, causing typical brown necrotic spots or streaks, followed by C. brevisporum, C. karstii, and C. kahawae subsp. ciggaro, whereas the two other species (C. fructicola and C. cliviae) showed no pathogenicity to mulberry. This study is the first report of these species associated with mulberry in China.


Assuntos
Colletotrichum , Morus , Filogenia , Virulência , China , Colletotrichum/patogenicidade , DNA Fúngico/genética , Morus/microbiologia , Doenças das Plantas/microbiologia , Folhas de Planta/microbiologia , Especificidade da Espécie
8.
Plant Dis ; 103(10): 2548-2558, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31432774

RESUMO

Several Pestalotiopsis-like species cause gray blight disease in tea plants, resulting in severe tea production losses. However, systematic and comprehensive research on the diversity, geographical distribution, and pathogenicity of pathogenic species associated with tea plants in China is limited. In this study, 168 Pestalotiopsis-like isolates were obtained from diseased tea plant leaves from 13 primary tea-producing provinces and cities in China. Based on a multilocus (internal transcribed spacer, translation elongation factor 1-α, and ß-tubulin gene region) phylogenetic analysis coupled with an assessment of conidial characteristics, 20 Neopestalotiopsis unclassified isolates, seven Pestalotiopsis species, including two novel (Pestalotiopsis menhaiensis and Pestalotiopsis sichuanensis), four known (Pestalotiopsis camelliae, Pestalotiopsis chamaeropis, Pestalotiopsis kenyana, and Pestalotiopsis rhodomyrtus) and one indistinguishable species, and three Pseudopestalotiopsis species, including two known (Pseudopestalotiopsis camelliae-sinensis and Pseudopestalotiopsis chinensis) and one indistinguishable species, were identified. This study is the first to evaluate Pestalotiopsis chamaeropis on tea plants in China. The geographical distribution and pathogenicity tests showed Pseudopestalotiopsis camelliae-sinensis to be the dominant cause of gray blight of tea plants in China. In vitro antifungal assays demonstrated that theobromine not only derepressed mycelial growth of the 29 representative isolates but also increased their growth. Correlation analysis revealed a linear positive relationship between the mycelial growth rate and pathogenicity (P = 0.0148).


Assuntos
Ascomicetos , Biodiversidade , Camellia sinensis , Doenças das Plantas , Ascomicetos/classificação , Ascomicetos/patogenicidade , Ascomicetos/fisiologia , Camellia sinensis/microbiologia , China , Filogenia , Doenças das Plantas/microbiologia , Especificidade da Espécie , Virulência
9.
An Acad Bras Cienc ; 91(suppl 3): e20190325, 2019 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-31460594

RESUMO

The West Indian (Trichechus manatus) and Amazonian (T. inunguis) manatees have a sympatric occurrence at the mouth of the Amazon River. A result of this interspecific encounter is the occurrence of hybrids, which are frequently found along the coasts of Amapá state in Brazil, French Guiana and Guyana. Here we present new genetic evidence indicating the occurrence of a hybrid swarm along the Guianas Shield coastline, which is an interspecific hybrid zone that also separates T. manatus populations located east (Brazil) and west (Caribbean, Gulf of Mexico, Florida and Antilles). In addition, we suggest that this hybrid population occupies a peculiar mangrove-rich environment under strong influence of the Amazon River plume, which requires an independent management and should be considered a special conservation area.


Assuntos
Variação Genética/genética , Hibridização Genética , Especificidade da Espécie , Trichechus inunguis/genética , Trichechus manatus/genética , Animais , Teorema de Bayes , Brasil , Região do Caribe , Guiana , Filogenia , Dinâmica Populacional , Rios , Trichechus inunguis/fisiologia , Trichechus manatus/fisiologia
10.
Genet Sel Evol ; 51(1): 35, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31262246

RESUMO

BACKGROUND: The Finnhorse was established as a breed more than 110 years ago by combining local Finnish landraces. Since its foundation, the breed has experienced both strong directional selection, especially for size and colour, and severe population bottlenecks that are connected with its initial foundation and subsequent changes in agricultural and forestry practices. Here, we used sequences of the mitochondrial control region and genomic single nucleotide polymorphisms (SNPs) to estimate the genetic diversity and differentiation of the four Finnhorse breeding sections: trotters, pony-sized horses, draught horses and riding horses. Furthermore, we estimated inbreeding and effective population sizes over time to infer the history of this breed. RESULTS: We found a high level of mitochondrial genetic variation and identified 16 of the 18 haplogroups described in present-day horses. Interestingly, one of these detected haplogroups was previously reported only in the Przewalski's horse. Female effective population sizes were in the thousands, but declines were evident at the times when the breed and its breeding sections were founded. By contrast, nuclear variation and effective population sizes were small (approximately 50). Nevertheless, inbreeding in Finnhorses was lower than in many other horse breeds. Based on nuclear SNP data, genetic differentiation among the four breeding sections was strongest between the draught horses and the three other sections (FST = 0.007-0.018), whereas based on mitochondrial DNA data, it was strongest between the trotters and the pony-sized and riding horses (ΦST = 0.054-0.068). CONCLUSIONS: The existence of a Przewalski's horse haplogroup in the Finnhorse provides new insights into the domestication of the horse, and this finding supports previous suggestions of a close relationship between the Finnhorse and eastern primitive breeds. The high level of mitochondrial DNA variation in the Finnhorse supports its domestication from a large number of mares but also reflects that its founding depended on many local landraces. Although inbreeding in Finnhorses was lower than in many other horse breeds, the small nuclear effective population sizes of each of its breeding sections can be considered as a warning sign, which warrants changes in breeding practices.


Assuntos
Variação Genética , Cavalos/genética , Animais , Cruzamento , DNA Mitocondrial , Feminino , Finlândia , Endogamia , Masculino , Polimorfismo de Nucleotídeo Único , Densidade Demográfica , Especificidade da Espécie
11.
Parasite ; 26: 38, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31259684

RESUMO

An inventory of Phlebotomine sandflies was carried out in the Ankarana tsingy located in far northern Madagascar. A total of 723 sandflies were used for morphological, morphometric, and molecular studies (sequencing of partial cytochrome B (mtDNA) and partial 28S (rDNA)). Nine species were identified: Phlebotomus fertei, Sergentomyia anka, Se. sclerosiphon, Se. goodmani, two species of the genus Grassomyia, as well as three new species described herein: Se. volfi n. sp., Se. kaltenbachi n. sp., and Se. ozbeli n. sp. The recognition of these new species is strongly supported by molecular analyses. The first two of the new species could not be classified into any existing subgenus, therefore we proposed two new subgenera (Ranavalonomyia subg. nov., and Riouxomyia subg. nov.), with combinations as: Sergentomyia (Ranavalonomyia) volfi and Sergentomyia (Riouxomyia) kaltenbachi. Our study reveals important molecular variability in Se. anka, with the recognition of a population whose taxonomic status remains below that of species. Our research confirms the need to further study the specific diversity of Malagasy sandflies, which until the start of this millennium remained mostly unknown.


Assuntos
Phlebotomus/classificação , Filogenia , Animais , Citocromos b/genética , DNA Mitocondrial/genética , DNA Ribossômico/genética , Feminino , Variação Genética , Insetos Vetores/classificação , Madagáscar , Masculino , Especificidade da Espécie
12.
Parasite ; 26: 44, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31335315

RESUMO

Anacanthorus (Anacanthorinae) is one of the most speciose and common genera of neotropical monogeneans, yet there are still many gaps in our knowledge concerning their diversity and phylogeny. We performed phylogenetic analyses of molecular sequences in order to investigate the phylogenetic position within the Dactylogyridae of Anacanthorus spp. infesting serrasalmids from two Brazilian river basins. Sequences of partial 28S rDNA obtained for nine species of Anacanthorus and Mymarothecium viatorum parasitizing serrasalmids and the published sequences of other members of the Dactylogyridae were included in the phylogenetic reconstruction. Phylogenetic analyses supported the monophyly of anacanthorine monogeneans. The Anacanthorinae (represented in this study by Anacanthorus spp.) formed a monophyletic group included in a large clade together with a group of solely freshwater Ancyrocephalinae and species of the Ancylodiscoidinae. Mymarothecium viatorum (Ancyrocephalinae) was placed within the clade of freshwater Ancyrocephalinae. The phylogenetic analyses indicated that the relationships among species of Anacanthorus reflect those of their serrasalmid hosts: the first subgroup includes a species specific to hosts assigned to Piaractus, a member of the "pacus" lineage; the second subgroup includes a species parasitizing the "Myleus-like pacus" lineage; and the third subgroup includes species parasitizing the lineage of the "true piranhas". We suggest that Anacanthorus and their serrasalmid hosts can be considered a useful model to assess host-parasite biogeography and coevolution in the neotropics. However, future studies focusing on a wider spectrum of host species and their specific Anacanthorus spp. are needed in order to investigate coevolution in this highly diversified system.


Assuntos
Caraciformes/parasitologia , Doenças dos Peixes/parasitologia , Filogenia , Trematódeos/classificação , Animais , Brasil , DNA de Helmintos/genética , DNA Ribossômico/genética , Análise de Sequência de DNA , Especificidade da Espécie
13.
Eur J Protistol ; 70: 17-31, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31352233

RESUMO

Two new colonial sessilid species, Opercularia miaoxinensis spec. nov. and Epistylis conica spec. nov., were isolated from the pereopods of freshwater crayfish, Procambarus clarkii in Hubei Province, China from 2016 to 2017. Both species were investigated by living observation, protargol impregnation, and molecular methods. Opercularia miaoxinensis spec. nov. is morphologically characterized by the following characteristics: spindle-shaped zooid, zooid size of 48-74×20-35µm in vivo, contractile vacuole ventrally located above macronucleus, and dichotomously branched stalk. Epistylis conica spec. nov. is characterized by conical zooid shape, zooid size of 56-70×22-39µm in vivo, C-shaped macronucleus with transverse orientation, dorsally located contractile vacuole, and dichotomously branched stalk. To further identify both species, phylogenetic trees were constructed based on small subunit ribosomal DNA (SSU rDNA) and ITS1-5.8S-ITS2 sequences. Both results showed that E. conica spec. nov. was part of a clade consisting of the majority of Epistylis species. Surprisingly, O. miaoxinensis spec. nov. also clustered within this large clade of Epistylis species and had a distant relationship with the other Opercularia species. These findings challenged the distinguishing morphological characteristics between Epistylididae and Operculariidae.


Assuntos
Cilióforos/classificação , Filogenia , China , Cilióforos/citologia , Cilióforos/genética , DNA de Protozoário/genética , DNA Ribossômico/genética , Especificidade da Espécie
14.
Zoo Biol ; 38(4): 371-383, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31257640

RESUMO

The longevity of zoo animals is increasing due to continuous improvement in husbandry and veterinary medicine. However, increasing age is correlated to a higher prevalence of neoplasia. Despite tremendous improvement in diagnoses and monitoring capacities, cancers are still a challenge for veterinarians within the global zoo community. The recent use of copper isotopes as biomarkers for neoplasia in both human and veterinary medicine is a promising and cost-effective diagnostic tool. Two hundred and twenty-nine serum samples from 10 different species of wild felids under human care were processed through mass spectrometry to determine the ratio of heavy and light copper isotopes (65 Cu/63 Cu). The results of this preliminary study exhibit an important variability between felid species, with a ratio ranging between -1.71 and 0.63. Additionally, copper isotopes seem to be a promising diagnostic tool in monitoring cancer in wild animals, as in human medicine, where the isotopic ratio decreases significantly with time in the presence of a tumor.


Assuntos
Cobre/sangue , Felidae/sangue , Neoplasias/veterinária , Animais , Biomarcadores Tumorais , Feminino , Masculino , Neoplasias/sangue , Neoplasias/diagnóstico , Especificidade da Espécie
15.
Ying Yong Sheng Tai Xue Bao ; 30(6): 2116-2128, 2019 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-31257787

RESUMO

Maximum Entropy (MaxEnt) model has been widely used in recent years. However, MaxEnt is highly inclined to produce misleading results if it is not well optimized. We summarized the researches about the model optimization for sampling bias correction, model complexity tuning, presence-absence threshold selection, and model evaluation. Spatial filtering performs best for sampling bias correction, while restricted background method shows the lowest efficacy. Model complexi-ty is mainly determined by three factors: The number of environmental variables, model feature types, and regularization multiplier. Variables filtering is needed when sample size is less than the number of environment variables. The criterion of variables selection should focus on their ecological significance rather than the co-linearity between them. The choice of feature types has relatively limi-ted effects on predictive performance of the model, therefore it is advised to choose simpler models. To control overfitting, it is necessary to conduct species-specific tuning on regularization multiplier, which was usually bigger than the default setting. There are three criteria called objectivity, equality and discriminability for selecting threshold to convert continuous predication (e.g. probability of presence) into binary results. Maximizing the sum of sensitivity and specificity is a sound method for threshold selection. Model evaluation methods could be classified into two main types: Threshold-independent and threshold-dependent. Among the threshold-independent evaluations, information criteria may offer significant advantages over AUC and COR. True Skill Statistics is a better index for threshold-dependent evaluations, because it takes both omission and commission errors into account, and is robust to pseudo-absence assumption and species prevalence.


Assuntos
Monitoramento Ambiental/métodos , Modelos Estatísticos , Entropia , Especificidade da Espécie
16.
Nat Commun ; 10(1): 2908, 2019 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-31266948

RESUMO

Cohesin and CTCF are master regulators of genome topology. How these ubiquitous proteins contribute to cell-type specific genome structure is poorly understood. Here, we explore quantitative aspects of topologically associated domains (TAD) between pluripotent embryonic stem cells (ESC) and lineage-committed cells. ESCs exhibit permissive topological configurations which manifest themselves as increased inter- TAD interactions, weaker intra-TAD interactions, and a unique intra-TAD connectivity whereby one border makes pervasive interactions throughout the domain. Such 'stripe' domains are associated with both poised and active chromatin landscapes and transcription is not a key determinant of their structure. By tracking the developmental dynamics of stripe domains, we show that stripe formation is linked to the functional state of the cell through cohesin loading at lineage-specific enhancers and developmental control of CTCF binding site occupancy. We propose that the unique topological configuration of stripe domains represents a permissive landscape facilitating both productive and opportunistic gene regulation and is important for cellular identity.


Assuntos
Fator de Ligação a CCCTC/química , Fator de Ligação a CCCTC/metabolismo , Elementos Facilitadores Genéticos , Células-Tronco Pluripotentes/metabolismo , Fator de Ligação a CCCTC/genética , Proteínas de Ciclo Celular/química , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Linhagem da Célula , Cromatina/química , Cromatina/genética , Cromatina/metabolismo , Proteínas Cromossômicas não Histona/química , Proteínas Cromossômicas não Histona/genética , Proteínas Cromossômicas não Histona/metabolismo , Células-Tronco Pluripotentes/química , Ligação Proteica , Domínios Proteicos , Especificidade da Espécie
17.
Nat Commun ; 10(1): 2919, 2019 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-31266962

RESUMO

Oncogenic mutations in KRAS or BRAF are frequent in colorectal cancer and activate the ERK kinase. Here, we find graded ERK phosphorylation correlating with cell differentiation in patient-derived colorectal cancer organoids with and without KRAS mutations. Using reporters, single cell transcriptomics and mass cytometry, we observe cell type-specific phosphorylation of ERK in response to transgenic KRASG12V in mouse intestinal organoids, while transgenic BRAFV600E activates ERK in all cells. Quantitative network modelling from perturbation data reveals that activation of ERK is shaped by cell type-specific MEK to ERK feed forward and negative feedback signalling. We identify dual-specificity phosphatases as candidate modulators of ERK in the intestine. Furthermore, we find that oncogenic KRAS, together with ß-Catenin, favours expansion of crypt cells with high ERK activity. Our experiments highlight key differences between oncogenic BRAF and KRAS in colorectal cancer and find unexpected heterogeneity in a signalling pathway with fundamental relevance for cancer therapy.


Assuntos
Neoplasias do Colo/enzimologia , Mucosa Intestinal/enzimologia , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Animais , Linhagem Celular Tumoral , Neoplasias do Colo/genética , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Regulação Neoplásica da Expressão Gênica , Humanos , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Camundongos , Camundongos Transgênicos , Quinases de Proteína Quinase Ativadas por Mitógeno/genética , Mutação , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas B-raf/metabolismo , Proteínas Proto-Oncogênicas p21(ras)/genética , Especificidade da Espécie
18.
J Zoo Wildl Med ; 50(2): 308-314, 2019 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-31260194

RESUMO

The objective of this study was to compare surface, esophageal, and cloacal temperatures in awake iguanas, chameleons, and snakes at two different ambient temperatures and in alligators at one ambient temperature. Surface, esophageal, and cloacal temperatures were measured in all animals twice, with exception of the alligators, where temperatures were taken once. The first set of temperature readings was done at lower environmental temperature. An analysis of variance (ANOVA) with a mixed-effect model was used to analyze the temperature difference between esophageal and cloacal temperature against each other, and against surface temperature. Significance was set at P < 0.05. In all animals, surface, esophageal, and cloacal temperatures increased significantly (P < 0.0001) with increased ambient temperature. Esophageal and cloacal temperature were not significantly different from each other in iguanas and chameleons at lower environmental temperature or in snakes and chameleons at high ambient temperature. In snakes, esophageal temperature 26.1 ± 1.6°C was significantly higher than cloacal temperature 25.2 ± 0.9°C (P = 0.0016) at lower ambient temperature. In alligators no difference between esophageal and cloacal temperature was observed at the given ambient temperature. Surface temperature was significantly lower than esophageal and cloacal temperature in all species investigated, except iguanas at lower ambient temperature. The results of this study suggest that in healthy awake iguanas and chameleons at any ambient temperature and in snakes at high ambient temperature, cloacal temperatures are reflective of esophageal temperature in the species evaluated. In alligators, rectal temperature reflected esophageal temperature at the given ambient temperature. Surface temperature in contrast was underestimating esophageal temperature in all species investigated.


Assuntos
Temperatura Corporal/fisiologia , Cloaca/fisiologia , Esôfago/fisiologia , Répteis/fisiologia , Fenômenos Fisiológicos da Pele , Animais , Especificidade da Espécie
19.
J Zoo Wildl Med ; 50(2): 315-321, 2019 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-31260195

RESUMO

Whole blood transfusions are an essential treatment modality during rehabilitation of stranded sea turtles, however, standardized protocols for transfusions are not available in reptile medicine. The objective of this study was to optimize a cross-matching protocol for sea turtle blood transfusions. Fresh venous blood samples from 15 turtles (n = 14 green turtles, Chelonia mydas [Cm]; n = 1 loggerhead sea turtle, Caretta caretta [Cc]) were tested using a temperature-appropriate (i.e., reflecting body temperature), time-sensitive protocol in 26 reactions using two procedures for cross-match evaluation at 30 and 60 min at ambient air and water bath temperature. There were no significant differences between both protocols at 30- and 60-min incubation times or between microscopic evaluations at 2 or 5 min. The major cross-match identified 7/22 incompatible Cm-Cm reactions as observed by microscopic erythrocyte agglutination. Minor cross-matches resulted in 6/22 incompatible Cm-Cm reactions. About half of all Cm-Cm reactions (12/22) were compatible by major and minor cross-match. All Cc-Cm reactions (4/4) were incompatible. A higher than expected proportion of incompatible Cm cross-matching reactions suggests preexisting antibodies to nonself erythrocyte antigens in this species, or other factors promoting erythrocyte aggregation or agglutination. Preliminary data across Cm and Cc suggests cross-species incompatibility. These results indicate that sea turtles may react to donor erythrocytes even at the first transfusion. Concurrent major and minor cross-matching using the proposed protocol at 30-min incubation at room temperature should be considered a necessary and effective way to test for patient and donor incompatibilities in sea turtles.


Assuntos
Tipagem e Reações Cruzadas Sanguíneas/veterinária , Transfusão de Sangue/veterinária , Tartarugas/sangue , Animais , Especificidade da Espécie
20.
J Zoo Wildl Med ; 50(2): 369-374, 2019 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-31260202

RESUMO

Intravascular access in batoid species is commonly achieved using the ventral coccygeal or radial wing vessels. However, these approaches can be difficult because of the presence of cartilage, lack of specific landmarks, species variation, and small vessel size in many species. This study used postmortem contrast radiography and gross dissection to develop landmarks for a new, dependable vascular access in three Myliobatiform species commonly maintained in captivity: Atlantic stingray (Hypanus sabinus), cownose ray (Rhinoptera bonasus), and smooth butterfly ray (Gymnura micrura). The mesopterygial vein provides quick vascular access and is suitable for administration of large fluid volumes and intravascular drugs. It is located immediately ventrolateral to the metapterygium cartilage, which sits adjacent to the coelomic cavity and supports the caudal half of the pectoral fin. Using the pectoral girdle and cranial third of the metapterygium cartilage as landmarks, vascular access can be achieved by directing a needle medially at approximately a 30° (adult cownose rays) or 45° angle (Atlantic stingrays, juvenile cownose rays, smooth butterfly rays) toward the metapterygium cartilage. Differences in the degree of needle direction are due to species and age-specific shapes of the metapterygium cartilage. The mesopterygial vein is an alternate site of quick and reliable venous access in batoid species.


Assuntos
Coleta de Amostras Sanguíneas/veterinária , Raias/anatomia & histologia , Envelhecimento , Animais , Feminino , Masculino , Especificidade da Espécie
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