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1.
J Appl Stat ; 51(5): 826-844, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38524797

RESUMO

The aim of this study is to propose a generalized odd log-logistic Maxwell mixture model to analyze the effect of gender and age groups on lifetimes and on the recovery probabilities of Chinese individuals with COVID-19. We add new properties of the generalized Maxwell model. The coefficients of the regression and the recovered fraction are estimated by maximum likelihood and Bayesian methods. Further, some simulation studies are done to compare the regressions for different scenarios. Model-checking techniques based on the quantile residuals are addressed. The estimated survival functions for the patients are reported by age range and sex. The simulation study showed that mean squared errors decay toward zero and the average estimates converge to the true parameters when sample size increases. According to the fitted model, there is a significant difference only in the age group on the lifetime of individuals with COVID-19. Women have higher probability of recovering than men and individuals aged ≥60 years have lower recovered probabilities than those who aged <60 years. The findings suggest that the proposed model could be a good alternative to analyze censored lifetime of individuals with COVID-19.

2.
J Anim Ecol ; 93(2): 183-195, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38192015

RESUMO

Understanding how different organisms cope with changing temperatures is vital for predicting future species' distributions and highlighting those at risk from climate change. As ectotherms, butterflies are sensitive to temperature changes, but the factors affecting butterfly thermoregulation are not fully understood. We investigated which factors influence thermoregulatory ability in a subset of the Mediterranean butterfly community. We measured adult thoracic temperature and environmental temperature (787 butterflies; 23 species) and compared buffering ability (defined as the ability to maintain a consistent body temperature across a range of air temperatures) and buffering mechanisms to previously published results from Great Britain. Finally, we tested whether thermoregulatory ability could explain species' demographic trends in Catalonia. The sampled sites in each region differ climatically, with higher temperatures and solar radiation but lower wind speeds in the Catalan sites. Both butterfly communities show nonlinear responses to temperature, suggesting a change in behaviour from heat-seeking to heat avoidance at approximately 22°C. However, the communities differ in the use of buffering mechanisms, with British populations depending more on microclimates for thermoregulation compared to Catalan populations. Contrary to the results from British populations, we did not find a relationship between region-wide demographic trends and butterfly thermoregulation, which may be due to the interplay between thermoregulation and the habitat changes occurring in each region. Thus, although Catalan butterfly populations seem to be able to thermoregulate successfully at present, evidence of heat avoidance suggests this situation may change in the future.


Assuntos
Borboletas , Animais , Borboletas/fisiologia , Regulação da Temperatura Corporal , Temperatura , Temperatura Alta , Ecossistema , Mudança Climática
3.
Sensors (Basel) ; 23(7)2023 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-37050831

RESUMO

A commercial pMOS transistor (MOSFET), 3N163 from Vishay (USA), has been characterized as a low-energy proton beam dosimeter. The top of the samples' housing has been removed to guarantee that protons reached the sensitive area, that is, the silicon die. Irradiations took place at the National Accelerator Centre (Seville, Spain). During irradiations, the transistors were biased to improve the sensitivity, and the silicon temperature was monitored activating the parasitic diode of the MOSFET. Bias voltages of 0, 1, 5, and 10 V were applied to four sets of three transistors, obtaining an averaged sensitivity that was linearly dependent on this voltage. In addition, the short-fading effect was studied, and the uncertainty of this effect was obtained. The bias voltage that provided an acceptable sensitivity, (11.4 ± 0.9) mV/Gy, minimizing the uncertainty due to the fading effect (-0.09 ± 0.11) Gy was 1 V for a total absorbed dose of 40 Gy. Therefore, this off-the-shelf electronic device presents promising characteristics as a dosimeter sensor for proton beams.

4.
Chromosome Res ; 31(1): 2, 2023 01 20.
Artigo em Inglês | MEDLINE | ID: mdl-36662301

RESUMO

Karyotypes are generally conserved between closely related species and large chromosome rearrangements typically have negative fitness consequences in heterozygotes, potentially driving speciation. In the order Lepidoptera, most investigated species have the ancestral karyotype and gene synteny is often conserved across deep divergence, although examples of extensive genome reshuffling have recently been demonstrated. The genus Leptidea has an unusual level of chromosome variation and rearranged sex chromosomes, but the extent of restructuring across the rest of the genome is so far unknown. To explore the genomes of the wood white (Leptidea) species complex, we generated eight genome assemblies using a combination of 10X linked reads and HiC data, and improved them using linkage maps for two populations of the common wood white (L. sinapis) with distinct karyotypes. Synteny analysis revealed an extensive amount of rearrangements, both compared to the ancestral karyotype and between the Leptidea species, where only one of the three Z chromosomes was conserved across all comparisons. Most restructuring was explained by fissions and fusions, while translocations appear relatively rare. We further detected several examples of segregating rearrangement polymorphisms supporting a highly dynamic genome evolution in this clade. Fusion breakpoints were enriched for LINEs and LTR elements, which suggests that ectopic recombination might be an important driver in the formation of new chromosomes. Our results show that chromosome count alone may conceal the extent of genome restructuring and we propose that the amount of genome evolution in Lepidoptera might still be underestimated due to lack of taxonomic sampling.


Assuntos
Borboletas , Animais , Borboletas/genética , Madeira , Mapeamento Cromossômico , Genoma , Sintenia , Cromossomos Sexuais , Evolução Molecular
5.
Int J Cosmet Sci ; 42(1): 29-35, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31461548

RESUMO

OBJECTIVE: A randomized study was designed to evaluate the potential cosmetic benefit of a biomimetic, niacinamide-containing moisturizing cream in oily, blemish-prone skin. METHODS: Healthy adult women with oily, blemish-prone skin were randomized to one of three treatment groups: test, control, or positive control. In the test group, subjects used the test product (containing 4% niacinamide), plus the standard cleanser (Simple® Kind to Skin Moisturizing Facial Wash). In the control group, subjects received no moisturizer but used the standard cleanser. In the positive control group, subjects used Vivatinell Acnecinamide® Gel Cream (containing 4% niacinamide) as a moisturizer and Neutrogena Visibly Clear® Spot Clearing Facial Wash (containing 2% salicylic acid) as a cleanser. The positive control regimen was included to provide a comparison for estimates of effect size. The primary objective was to evaluate skin moisturization as a change from baseline in corneometer values at 8 h for the test regimen vs. the control regimen. Analysis of covariance was applied for the primary efficacy analysis. RESULTS: A total of 132 subjects were randomized with 44 included in each treatment group. A significant difference was observed in the primary endpoint for the test regimen compared with the control regimen (least-squares mean difference [95% CI]: 3.12 [0.68, 5.56], P = 0.0128). A trend was observed in favour of the positive control regimen compared with the control regimen. Secondary measurements of moisturization supported the primary efficacy outcome. Assessment of blemishes showed a significant difference between the test regimen vs. the control regimen for change from baseline in mean total blemish count at Week 8 (least-squares mean difference [95% CI]: -1.80 [-3.41, -0.19], P = 0.0290). No statistical comparisons between the positive control group and the test group were performed. CONCLUSION: This study provides proof-of-concept evidence that a novel lamellar lipid moisturizer containing niacinamide, in combination with a standard cleanser, can help moisturize the skin and provide an overall improvement in the complexion appearance of people with blemish-prone skin. STUDY REGISTRATION: NCT03093181.


OBJECTIF: Une étude randomisée a été conçue pour évaluer le bénéfice cosmétique potentiel d'une crème hydratante biomimétique contenant du niacinamide sur une peau grasse sujette aux imperfections. MÉTHODES: Des femmes adultes en bonne santé, à peau grasse sujette aux imperfections, ont été randomisées dans l'un des trois groupes de traitement : test, témoin ou témoin positif. Dans le groupe test, les sujets ont utilisé le produit testé (contenant 4 % de niacinamide), plus le nettoyant standard (Nettoyant visage Simple® doux pour la peau). Dans le groupe témoin, les sujets n'ont reçu aucune crème hydratante mais ont utilisé le nettoyant standard. Dans le groupe témoin positif, les sujets ont utilisé le gel crème Vivatinell Acnecinamide® (contenant 4 % de niacinamide) comme crème hydratante et le nettoyant visage pour réduire les imperfections Neutrogena Visibly Clear® (contenant 2 % d'acide salicylique) comme nettoyant. Le schéma de traitement du groupe témoin positif était inclus pour fournir une comparaison des estimations de la taille de l'effet. L'objectif principal était d'évaluer l'hydratation de la peau par le changement par rapport à la référence des valeurs du cornéomètre à 8 h pour le schéma de traitement testé par rapport au schéma de traitement témoin. Une analyse de covariance a été appliquée pour l'analyse de l'efficacité primaire. RÉSULTATS: Un total de 132 sujets ont été randomisés, dont 44 inclus dans chaque groupe de traitement. Une différence significative a été observée dans le critère d'évaluation principal en faveur du schéma de traitement testé par rapport au schéma de traitement témoin (différence moyenne des moindres carrés [IC à 95 %] : 3,12 [0,68, 5,56], P = 0,0128). Une tendance a été observée en faveur du schéma de traitement témoin positif par rapport au schéma de traitement témoin. Les mesures secondaires de l'hydratation ont appuyé le résultat principal d'efficacité. L'évaluation des imperfections a montré une différence significative entre le schéma de traitement testé par rapport au schéma de traitement témoin en ce qui concerne le changement par rapport à la référence dans le nombre moyen total d'imperfections à la semaine 8 (différence moyenne des moindres carrés [IC à 95 %] : _1,80 [_3,41, _0,19], P = 0,0290). Aucune comparaison statistique entre le groupe témoin positif et le groupe test n'a été réalisée. CONCLUSION: Cette étude fournit des éléments de preuve de concept qu'une nouvelle crème hydratante lipidique lamellaire à base de niacinamide, en association avec un nettoyant standard, peut permettre d'hydrater la peau et fournir une amélioration globale de l'aspect du teint chez des personnes dont la peau est sujette aux imperfections. Numéro d'enregistrement de l'étude : NCT03093181.


Assuntos
Acne Vulgar/prevenção & controle , Biomimética , Cosméticos , Niacinamida/administração & dosagem , Pele/efeitos dos fármacos , Adolescente , Adulto , Feminino , Humanos , Pessoa de Meia-Idade , Estudo de Prova de Conceito , Adulto Jovem
7.
Neotrop Entomol ; 46(5): 514-523, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28116647

RESUMO

DNA barcoding is a technique used primarily for the documentation and identification of biological diversity based on mitochondrial DNA sequences. Butterflies have received particular attention in DNA barcoding studies, although varied performance may be obtained due to different scales of geographic sampling and speciation processes in various groups. The montane Andean Satyrinae constitutes a challenging study group for taxonomy. The group displays high richness, with more of 550 species, and remarkable morphological similarity among taxa, which renders their identification difficult. In the present study, we evaluated the effectiveness of DNA barcodes in the identification of montane Andean satyrines and the effect of increased geographical scale of sampling on identification performance. Mitochondrial sequences were obtained from 104 specimens of 39 species and 16 genera, collected in a forest remnant in the northwest Andes. DNA barcoding has proved to be a useful tool for the identification of the specimens, with a well-defined gap and producing clusters with unambiguous identifications for all the morphospecies in the study area. The expansion of the geographical scale with published data increased genetic distances within species and reduced those among species, but did not generally reduce the success of specimen identification. Only in Forsterinaria rustica (Butler, 1868), a taxon with high intraspecific variation, the barcode gap was lost and low support for monophyly was obtained. Likewise, expanded sampling resulted in a substantial increase in the intraspecific distance in Morpho sulkowskyi (Kollar, 1850); Panyapedaliodes drymaea (Hewitson, 1858); Lymanopoda obsoleta (Westwood, 1851); and Lymanopoda labda Hewitson, 1861; but for these species, the barcode gap was maintained. These divergent lineages are nonetheless worth a detailed study of external and genitalic morphology variation, as well as ecological features, in order to determine the potential existence of cryptic species. Even including these cases, DNA barcoding performance in specimen identification was 100% successful based on monophyly, an unexpected result in such a taxonomically complicated group.


Assuntos
Borboletas/classificação , Código de Barras de DNA Taxonômico , Filogenia , Animais , Colômbia , Variação Genética , Genética Populacional , Geografia
8.
Avian Pathol ; 46(1): 52-58, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27400065

RESUMO

Infectious bronchitis virus (IBV) is a coronavirus which affects chickens of all ages. IBV mainly causes respiratory disease but can also result in reduced weight gain, reduced egg production, increased frequency of abnormal eggs and increased rates of mortality. Vaccination is the most important way to control the disease. Nevertheless, novel strains of infectious bronchitis (IB) continue to emerge in the field. In order to respond promptly, combinations of existing IB vaccines are frequently tested to see whether they can provide cross-protection. The efficacy of a combination of vaccines based on Massachusetts, Dutch and QX-like IB strains against emerging IB Israel variant 2 and IB 793B strains was assessed by means of four challenge studies. At least 80% of the birds vaccinated with IB H120 (Mass type) combined with IB D274 (Dutch type) followed by a QX-like IB vaccine booster or vaccinated with a combination of IB H120, IB D274 and QX-like IB were protected against a challenge with IB 793B. In addition, IB 1263 (Mass type) boosted by QX-like IB showed an 85% protection following challenge with IB 793B. A combination of IB H120 and IB D274 boosted by QX-like IB vaccine conferred 70% protection whilst H120 and IB D274 combination on its own showed 61.1% protection against Israel variant 2 challenge. IB 1263 boosted by a QX-like IB vaccine showed 50% protection against IB Israel variant 2. Therefore, it can be concluded that a combination of the IB H120, IB D274 and QX-like IB confers broad protection against different non-related virulent IB strains.


Assuntos
Bronquite/veterinária , Galinhas/imunologia , Infecções por Coronavirus/veterinária , Vírus da Bronquite Infecciosa/imunologia , Doenças das Aves Domésticas/prevenção & controle , Vacinação/veterinária , Vacinas Virais/imunologia , Animais , Bronquite/prevenção & controle , Bronquite/virologia , Galinhas/virologia , Infecções por Coronavirus/prevenção & controle , Infecções por Coronavirus/virologia , Proteção Cruzada , Vírus da Bronquite Infecciosa/patogenicidade , Israel , Massachusetts , Doenças das Aves Domésticas/virologia , Sorogrupo , Organismos Livres de Patógenos Específicos , Vacinas Atenuadas/imunologia , Virulência
9.
Int J Cosmet Sci ; 38(6): 576-580, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27012956

RESUMO

OBJECTIVE: Strategies to optimize the development of sunscreens include the use of theoretical sunscreen simulators to predict sun protection factor (SPF) and UVA protection factor (UVA-PF) and in vitro measurements of UVA-PF. The aims of this study were to assess the correlations between (1) SPF and UVA-PF results obtained in a theoretical sunscreen simulator with those observed in vivo (SPF and UVA-PF) and in vitro (UVA-PF) and (2) the results of UVA-PF observed in vitro and in vivo for products in different galenic forms containing or not pigments. METHODS: BASF Sunscreen Simulator software was used to evaluate the theoretical performance of formulations regarding SPF and UVA protection. In vitroUVA-PF and in vivoSPF were determined for all formulations. UVA-PFin vivo measurements were carried out only on products for which the galenic forms (compact foundations and lip balms) or the presence of dye or pigments could make the results of UVA-PFin vitro less reliable (due to a possible uneven film formation). RESULTS: The results of the SPF calculated by the BASF Sunscreen Simulator presented a very good correlation with SPF observed in vivo in the absence of pigments (r = 0.91; P < 0.05) and a good correlation in the presence of pigments (r = 0.70; P < 0.05). The UVA-PF calculated by the BASF Sunscreen Simulator also exhibited a very good correlation with UVA-PF measured in vitro (r = 0.88; P < 0.05) for the formulations not containing pigment and a good correlation (r = 0.75; P < 0.05) for the formulations containing pigment. The correlation of same UVA-PF calculated by BASF Sunscreen Simulator with UVA-PF measured in vivo for the formulations containing pigment was r = 0.74 (P < 0.05), which is considered good. In addition, the measurements of UVA-PFin vivo presented a good correlation with the values obtained in vitro (r = 0.74; P < 0.05). CONCLUSION: In the present study, the use of BASF Sunscreen Simulator and in vitroUVA tests showed good correlations with in vivo results and could be considered as valuable resources in the development of sunscreens.


Assuntos
Fator de Proteção Solar , Protetores Solares , Humanos
10.
Actas dermo-sifiliogr. (Ed. impr.) ; 106(3): 219-225, abr. 2015. ilus, graf, tab
Artigo em Espanhol | IBECS | ID: ibc-136078

RESUMO

INTRODUCCIÓN: Telaprevir es un fármaco que administrado junto a interferón y ribavirina incrementa de forma significativa la respuesta al tratamiento de la infección por el virus de la hepatitis C. Sin embargo, su empleo incrementa también la probabilidad de desarrollar efectos adversos, en muchos casos cutáneos que pueden condicionar el mantenimiento del tratamiento. OBJETIVO: Conocer la incidencia, características clínicas y evolutivas y respuesta al tratamiento de las toxicodermias por telaprevir en el contexto del tratamiento de la infección por el virus de la hepatitis C. MATERIAL Y MÉTODOS: Estudio prospectivo observacional realizado entre mayo de 2012 y julio de 2013 en el que se incluyeron aquellos pacientes que iniciaron tratamiento con telaprevir durante ese periodo. En aquellos en los que se detectaron toxicodermia se recogieron los datos demográficos de los pacientes, las características clínicas de las lesiones y la evolución tras la aplicación de las recomendaciones de las guías clínicas. RESULTADOS: De un total de 43 pacientes que recibieron tratamiento triple un 46% presentó toxicodermia atribuible a telaprevir. En el 90% de los casos esta fue leve o moderada (grados 1 o 2) y consistió en un exantema constituido por pápulas y placas eritematoedematosas y descamativas. En alrededor de un tercio de los pacientes se comprobó la progresión de la toxicodermia, principalmente en extensión, durante el curso del tratamiento. En 2 casos (4,6%) las lesiones cutáneas condicionaron la suspensión del fármaco. Un 79% de los tratados (34 pacientes) alcanzó una respuesta viral sostenida tras el tratamiento. CONCLUSIONES: Las toxicodermias asociadas a telaprevir son frecuentes en el curso del tratamiento y a menudo progresivas. Sin embargo, solo de forma excepcional condicionan su suspensión


INTRODUCTION: When co-administered with interferon and ribavirin, the prescription drug telaprevir significantly improves treatment response in patients with chronic hepatitis C virus (HCV) infection. Its use, however, also increases the likelihood of adverse effects that may lead to discontinuation of treatment. Cutaneous adverse effects are particularly common. OBJECTIVE: To determine the frequency and clinical characteristics of drug eruptions induced by telaprevir in patients receiving HCV treatment and to analyze the clinical course of lesions and response to treatment. MATERIAL AND METHODS: We performed a prospective observational study of all patients who started a treatment regimen that included telaprevir between May 2012 and July 2013. We recorded the demographic characteristics of the patients who developed telaprevir-induced eruptions, and analyzed the clinical characteristics of the lesions and their clinical course following the application of guideline-based treatment recommendations. RESULTS: Twenty (46%) of the 43 patients who received triple therapy with interferon, ribavirin, and telaprevir during the study period developed drug reactions attributable to telaprevir. The reaction was classified as mild or moderate (grades 1 or 2) in 90% of cases and consisted of an exanthem with erythematous-edematous scaling plaques and papules. The rash worsened, mainly by spreading, in about one-third of cases. The skin lesions led to discontinuation of treatment in 2 patients (4.6%). Sustained viral response was achieved in 34 patients (79%). CONCLUSIONS: Telaprevir-induced eruptions are common and often progress, but they rarely require patients to discontinue treatment


Assuntos
Humanos , Masculino , Feminino , Adulto , Idoso , Pessoa de Meia-Idade , Toxidermias/etiologia , Hepacivirus/isolamento & purificação , Hepatite C Crônica/tratamento farmacológico , Oligopeptídeos/efeitos adversos , Inibidores de Serina Proteinase/efeitos adversos , Estudo Observacional , Progressão da Doença , Quimioterapia Combinada , Genótipo , Interferons/uso terapêutico , Ribavirina/uso terapêutico , Estudos Prospectivos
11.
Actas Dermosifiliogr ; 106(3): 219-25, 2015 Apr.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-25444579

RESUMO

INTRODUCTION: When co-administered with interferon and ribavirin, the prescription drug telaprevir significantly improves treatment response in patients with chronic hepatitis C virus (HCV) infection. Its use, however, also increases the likelihood of adverse effects that may lead to discontinuation of treatment. Cutaneous adverse effects are particularly common. OBJECTIVE: To determine the frequency and clinical characteristics of drug eruptions induced by telaprevir in patients receiving HCV treatment and to analyze the clinical course of lesions and response to treatment. MATERIAL AND METHODS: We performed a prospective observational study of all patients who started a treatment regimen that included telaprevir between May 2012 and July 2013. We recorded the demographic characteristics of the patients who developed telaprevir-induced eruptions, and analyzed the clinical characteristics of the lesions and their clinical course following the application of guideline-based treatment recommendations. RESULTS: Twenty (46%) of the 43 patients who received triple therapy with interferon, ribavirin, and telaprevir during the study period developed drug reactions attributable to telaprevir. The reaction was classified as mild or moderate (grades 1 or 2) in 90% of cases and consisted of an exanthem with erythematous-edematous scaling plaques and papules. The rash worsened, mainly by spreading, in about one-third of cases. The skin lesions led to discontinuation of treatment in 2 patients (4.6%). Sustained viral response was achieved in 34 patients (79%). CONCLUSIONS: Telaprevir-induced eruptions are common and often progress, but they rarely require patients to discontinue treatment.


Assuntos
Toxidermias/etiologia , Hepacivirus/isolamento & purificação , Hepatite C Crônica/tratamento farmacológico , Oligopeptídeos/efeitos adversos , Inibidores de Serina Proteinase/efeitos adversos , Adulto , Idoso , Progressão da Doença , Toxidermias/epidemiologia , Quimioterapia Combinada , Feminino , Genótipo , Hepacivirus/genética , Hepatite C Crônica/virologia , Humanos , Interferons/uso terapêutico , Masculino , Pessoa de Meia-Idade , Oligopeptídeos/uso terapêutico , Estudos Prospectivos , Ribavirina/uso terapêutico , Inibidores de Serina Proteinase/uso terapêutico , Índice de Gravidade de Doença
12.
Genet Mol Res ; 13(1): 838-49, 2014 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-24615048

RESUMO

The chicken (Gallus gallus) embryo has been used as a classic model system for developmental studies because of its easy accessibility for surgical manipulation during embryonic development. Sex determination in birds is chromosomally based (ZZ for males and ZW for females); however, the basic mechanism of sex determination is still unknown. Here, the dynamics of expression of candidate genes implicated in vertebrate sex determination and differentiation were studied during embryonic chicken gonadal development. Gene expression profiles were obtained before, during, and after gonadal sex differentiation in females and males for DMRT1, SOX3, SOX9, DAX1, SCII, HINTZ, HINTW, and the male hypermethylated (MHM) region. Transcripts for the HINTZ, DMRT1, DAX1, SCII, and SOX9 genes were observed in both sexes, but expression was higher in male gonads and may be correlated with testicular differentiation. The expression patterns of HINTW, SOX3, and MHM suggest that they may act in ovary development and may be involved in meiosis entry. MHM was upregulated and DMRT1 was downregulated in females at the same developmental stage. This may indicate a regulation of DMRT1 by MHM ncRNA. Similar dynamics were observed between HINTW and HINTZ. This study reports on the MHM expression profile during gonadal development and its correlation with the expression of genes involved in vertebrate sex determination.


Assuntos
Gônadas/crescimento & desenvolvimento , Processos de Determinação Sexual , Diferenciação Sexual/genética , Animais , Embrião de Galinha , Metilação de DNA/genética , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Masculino , Cromossomos Sexuais/genética , Testículo/crescimento & desenvolvimento , Testículo/metabolismo
13.
J Evol Biol ; 26(10): 2095-106, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23909947

RESUMO

Molecular studies of natural populations are often designed to detect and categorize hidden layers of cryptic diversity, and an emerging pattern suggests that cryptic species are more common and more widely distributed than previously thought. However, these studies are often decoupled from ecological and behavioural studies of species divergence. Thus, the mechanisms by which the cryptic diversity is distributed and maintained across large spatial scales are often unknown. In 1988, it was discovered that the common Eurasian Wood White butterfly consisted of two species (Leptidea sinapis and Leptidea reali), and the pair became an emerging model for the study of speciation and chromosomal evolution. In 2011, the existence of a third cryptic species (Leptidea juvernica) was proposed. This unexpected discovery raises questions about the mechanisms preventing gene flow and about the potential existence of additional species hidden in the complex. Here, we compare patterns of genetic divergence across western Eurasia in an extensive data set of mitochondrial and nuclear DNA sequences with behavioural data on inter- and intraspecific reproductive isolation in courtship experiments. We show that three species exist in accordance with both the phylogenetic and biological species concepts and that additional hidden diversity is unlikely to occur in Europe. The Leptidea species are now the best studied cryptic complex of butterflies in Europe and a promising model system for understanding the formation of cryptic species and the roles of local processes, colonization patterns and heterospecific interactions for ecological and evolutionary divergence.


Assuntos
Borboletas/genética , Variação Genética , Isolamento Reprodutivo , Animais , Borboletas/fisiologia , DNA/química , DNA Mitocondrial/química , Fluxo Gênico , Marcadores Genéticos , Geografia , Filogenia , Análise de Sequência de DNA , Comportamento Sexual Animal
14.
Neotrop Entomol ; 42(2): 146-57, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23949748

RESUMO

Colombia is one of the most biodiverse countries on the planet. However, economic and scientific investment in completing inventories of its biodiversity has been relatively poor in comparison with other Neotropical countries. Butterflies are the best studied group of invertebrates, with the highest proportion of known to expected species. More than 3,200 species of butterflies have been recorded in Colombia, although the study of the still many unexplored areas will presumably increase this number. This work provides a list of Ithomiini butterflies collected in the department of Antioquia and estimates the total number of species present, based on revision of entomological collections, records in the literature and field work performed between 2003 and 2011. The list includes 99 species and 32 genera, representing 27% of all Ithomiini species. We report 50 species of Ithomiini not formerly listed from Antioquia, and found the highest diversity of ithomiine species to be at middle elevations (900-1,800 m). The mean value of the Chao2 estimator for number of species in Antioquia is 115 species, which is close to a predicted total of 109 based on known distributions of other Ithomiini not yet recorded from the department. Nine species are potentially of particular conservation importance because of their restricted distributions, and we present range maps for each species. We also highlight areas in Antioquia with a lack of biodiversity knowledge to be targeted in future studies. This paper contributes to mapping the distribution of the Lepidoptera of Antioquia department in particular and of Colombia in general.


Assuntos
Borboletas , Distribuição Animal , Animais , Biodiversidade , Borboletas/classificação , Colômbia
15.
Genet Mol Res ; 10(4): 3937-41, 2011 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-22033907

RESUMO

The testis-specific protein Y-encoded gene (TSPY) is a Y-specific gene present in variable copy number in many mammalian species, including cattle. We tested the applicability of the TSPY gene as a Y-specific marker to predict preimplantation embryo sex in Nelore (Bos indicus) cattle. Two blastomeres were removed from each embryo. A total of 36 single blastomeres and the remaining cells of their 18 matched in vitro conceived embryos were screened for TSPY amplification by nested-PCR. The results obtained from a single blastomere and the remaining cells of the same embryo were concordant in all cases. All blastomeres (16/16) from eight embryos produced with sexed sperm (specific for production of male embryos) were TSPY-positive. We conclude that TSPY is a good male-specific marker, the usefulness of which is probably enhanced by the high copy number. Other methods that are less time-consuming, such as real-time PCR, could be improved with the use of the TSPY gene sequences to generate primers and/or probes. This is the first report to demonstrate the applicability of the TSPY gene for sexing single cells in cattle.


Assuntos
Blastômeros/metabolismo , Proteínas de Ciclo Celular/genética , Reação em Cadeia da Polimerase/métodos , Análise para Determinação do Sexo/métodos , Animais , Bovinos , Eletroforese em Gel de Poliacrilamida , Embrião de Mamíferos/metabolismo , Feminino , Masculino
16.
Genet Mol Res ; 10(3): 1409-15, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21823090

RESUMO

The CYP21 (steroid 21-hydroxylase) gene is involved in the synthesis of steroid hormones. Bov-A2 is a retroposon that is common in ruminant genomes. The promoter region of bovine CYP21 contains a short interspersed nucleotide element of Bov-A2, which overlaps a putative Sp1 binding site. We looked for RFLP/HpaII polymorphism in the Bov-A2 element in bovine Zebu breeds by PCR-RFLP, and examined whether polymorphism in this element is associated with methylation. Among DNA samples from 135 Brazilian Zebu breed cattle, we identified an RFLP/HpaII polymorphism (T/C), which, based on a restriction methylation-sensitive assay employing HpaII and isoschizomer MspI enzymes (methylation-sensitive and -non-sensitive enzymes, respectively), appears to be a DNA methylation point. This is the first report of this polymorphism and on DNA methylation in the bovine CYP21 promoter region in Brazilian Zebu cattle.


Assuntos
Metilação de DNA/genética , Regiões Promotoras Genéticas/genética , Esteroide 21-Hidroxilase/genética , Alelos , Animais , Bovinos , Epigenômica , Genótipo , Polimorfismo Genético/genética , Polimorfismo de Fragmento de Restrição/genética
17.
Mol Phylogenet Evol ; 61(1): 237-43, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21669295

RESUMO

Despite much research on the socially parasitic large blue butterflies (genus Maculinea) in the past 40 years, their relationship to their closest relatives, Phengaris, is controversial and the relationships among the remaining genera in the Glaucopsyche section are largely unresolved. The evolutionary history of this butterfly section is particularly important to understand the evolution of life history diversity connected to food-plant and host-ant associations in the larval stage. In the present study, we use a combination of four nuclear and two mitochondrial genes to reconstruct the phylogeny of the Glaucopsyche section, and in particular, to study the relationships among and within the Phengaris-Maculinea species. We find a clear pattern between the clades recovered in the Glaucopsyche section phylogeny and their food-plant associations, with only the Phengaris-Maculinea clade utilising more than one plant family. Maculinea is, for the first time, recovered with strong support as a monophyletic group nested within Phengaris, with the closest relative being the rare genus Caerulea. The genus Glaucopsyche is polyphyletic, including the genera Sinia and Iolana. Interestingly, we find evidence for additional potential cryptic species within the highly endangered Maculinea, which has long been suspected from morphological, ecological and molecular studies.


Assuntos
Borboletas/classificação , Borboletas/genética , Animais , Evolução Biológica , Borboletas/fisiologia , Núcleo Celular/genética , DNA Mitocondrial/classificação , DNA Mitocondrial/genética , Evolução Molecular , Estágios do Ciclo de Vida , Mitocôndrias/genética , Linhagem , Filogenia
18.
Avian Pathol ; 40(1): 93-102, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21331953

RESUMO

The attenuation of infectious bronchitis (IB) QX-like virus strain L1148 is described. The virus was passaged multiple times in embryonated specific pathogen free (SPF) chicken eggs, and at different passage levels samples were tested for safety for the respiratory tract and kidneys in 1-day-old SPF chickens. There was a clear decrease in pathogenicity for the respiratory tract and kidneys when the virus had undergone a large number of passages. Passage level 80 was investigated for safety for the reproductive tract in 1-day-old and 7-day-old SPF chickens. In 1-day-old chickens, 12.5% of the vaccinated birds had macroscopic lesions. No lesions were observed if the chickens had been vaccinated at 7 days of age. Passage level 80 was investigated for its ability to spread from vaccinated to non-vaccinated chickens and for dissemination in the body. The virus was able to spread from vaccinated chickens to groups of non-vaccinated chickens, and in the vaccinated birds the virus was found frequently in oro-pharyngeal and cloacal swabs. A fragment of the hypervariable region of the S1 protein of passage level 80 was sequenced and revealed nucleotide changes resulting in two amino acid substitutions. Passage level 80 was given additional passages to levels 82 and 85. Both passage levels were tested for efficacy in SPF chickens and passage level 85 was tested for efficacy in commercial chickens with maternally derived antibodies (MDA) against a challenge with QX-like strain IB D388. In both SPF chickens and chickens with MDA, the vaccines based on strain IB L1148 were efficacious against challenge.


Assuntos
Galinhas , Infecções por Coronavirus/veterinária , Vírus da Bronquite Infecciosa/imunologia , Doenças das Aves Domésticas/prevenção & controle , Vacinas Virais , Animais , Anticorpos Antivirais/sangue , Infecções por Coronavirus/prevenção & controle , Feminino , Vacinação/veterinária , Vacinas Atenuadas/efeitos adversos , Vacinas Atenuadas/imunologia , Vacinas Virais/efeitos adversos , Vacinas Virais/imunologia
19.
Rev Esp Sanid Penit ; 12(1): 21-8, 2010 Jun.
Artigo em Espanhol | MEDLINE | ID: mdl-23128485

RESUMO

INTRODUCTION: The aim of this study is to establish the prevalence of HIV infection and associated risk behaviours amongst inmates at the Montevideo Prison in 2005. MATERIALS AND METHODS: The prevalence of HIV infection and different risk practices were analysed in a sample of 191 individuals by means of a serological study and personal interview based on a structured questionnaire. RESULTS: A prevalence of 6.5% was found for HIV infection in prison. The variables that proved to be risk factors were: previous prison sentences (p=0.009; OR= 9.51; IC95%: 1.31-144,0), having had an HIV (+) sexual partner in the past (p=0.000025; OR=7.87; IC95%: 2.58-23.9), current relationship with an HIV (+) partner (p=0.0013; OR=14.24; IC95%: 2.84-70.65), intravenous drug use (p=0.0001; OR=22.6; IC95%: 6.87-78.9), intravenous drug use in prison (p=0.03; OR=4.93; IC95%: 1.10-22.81) and sharing needles (p=0.004; OR=12.5; IC95%: 1.72-114.7).

20.
Rev. esp. sanid. penit ; 12(1): 21-28, 2010. tab
Artigo em Espanhol | IBECS | ID: ibc-79301

RESUMO

Introducción: El objetivo del trabajo consiste en conocer la prevalencia de la infección por VIH y las conductas de riesgoasociadas en reclusos alojados en el Complejo Penitenciario de Montevideo en el año 2005.Material y Método: Se analiza de prevalencia de la infección VIH y las distintas prácticas de riesgo en una muestra de 291individuos abordada mediante un estudio serológico y entrevista personal a partir de un cuestionario estructurado.Resultados: Se halló una prevalencia de 6.5% para la infección VIH en prisión. Las variables que demostraron ser factoresde riesgo para la infección VIH en la prisión fueron: poseer antecedentes de haber estado en prisión (p=0,009; OR= 9,51;IC95%: 1,31-144,0), el haber tenido una pareja sexual VIH (+) en el pasado (p=0,000025; OR=7,87; IC95%: 2,58-23,9), el teneractualmente una pareja VIH (+) (p=0,0013; OR=14,24; IC95%:2,84-70,65), haberse inyectado drogas I/V (p=0,0001; OR=22,6;IC95%: 6,87-78,9), el haberse inyectado drogas I/V en la prisión (p=0,03; OR=4,93; IC95%: 1,10-22,81) y la práctica de compartirel material de inyección (p=0,004; OR=12,5; IC95%: 1,72-114,7)(AU)


Introduction: The aim of this study is to establish the prevalence of HIV infection and associated risk behaviours amongstinmates at the Montevideo Prison in 2005.Materials and Methods: The prevalence of HIV infection and different risk practices were analysed in a sample of 191individuals by means of a serological study and personal interview based on a structured questionnaire.Results: A prevalence of 6.5% was found for HIV infection in prison. The variables that proved to be risk factors were: previousprison sentences (p=0.009; OR= 9.51; IC95%: 1.31-144,0), having had an HIV (+) sexual partner in the past (p=0.000025;OR=7.87; IC95%: 2.58-23.9), current relationship with an HIV (+) partner (p=0.0013; OR=14.24; IC95%: 2.84-70.65), intravenousdrug use (p=0.0001; OR=22.6; IC95%: 6.87-78.9), intravenous drug use in prison (p=0.03; OR=4.93; IC95%: 1.10-22.81)and sharing needles (p=0.004; OR=12.5; IC95%: 1.72-114.7)(AU)


Assuntos
Humanos , Masculino , Adulto , Pessoa de Meia-Idade , Comportamento Sexual/psicologia , Fatores de Risco , Prisões/organização & administração , Prisões , Síndrome da Imunodeficiência Adquirida/epidemiologia , Síndrome da Imunodeficiência Adquirida/prevenção & controle , Parceiros Sexuais/psicologia , Uruguai/epidemiologia , Sorologia/métodos , Sorologia/tendências , Sorodiagnóstico da AIDS/métodos
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