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1.
Reprod Domest Anim ; 59(4): e14556, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38566398

RESUMO

Scrotal surface thermography is a non-invasive method for assessing testicular thermoregulation in stallions; however, few studies have explored the application of this technique concerning the thermal physiology of equine reproductive systems. This study aimed to evaluate the consistency of testicular thermoregulation in stallions over a year using thermography to measure the scrotal surface temperature (SST). Moreover, we assessed the best region for measuring the surface body temperature compared with the SST. Ten light-breed stallions were used in the experiment. Thermographic images of the scrotal and body surfaces (neck and abdomen) were captured. Fresh, cooled and frozen-thawed semen samples were evaluated to verify the impact of thermoregulation on semen quality. Testicular thermoregulation was maintained throughout the year in stallions amidst changes in the external temperature, as evidenced by the weak correlation between the SST and ambient temperature. A lower correlation was observed between the environmental temperature and body surface temperature (BTS) obtained from the abdomen (BTS-A; R = .4772; p < .0001) than with that obtained from the neck (BTS-N; R = .7259; p < .0001). Moreover, both BTS-A and SST were simultaneously captured in a single image. The consistent quality of the fresh, cooled and frozen semen suggests efficient thermoregulation in stallions throughout the year.


Assuntos
Análise do Sêmen , Termografia , Animais , Cavalos , Masculino , Temperatura , Termografia/veterinária , Termografia/métodos , Análise do Sêmen/veterinária , Escroto/fisiologia , Testículo/fisiologia , Sêmen/fisiologia
2.
Cryo Letters ; 44(2): 110-108, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37883160

RESUMO

BACKGROUND: The synergistic action among the different extracellular cryoprotectants could improve somatic cell quality after thawing and provide bases for the formation of biobanks for red-rumped agoutis. OBJECTIVE: This study evaluated the interactions among sucrose (SUC) and concentrations of serum fetal bovine (FBS) on the cryopreservation of somatic cells derived from red-rumped agoutis. MATERIALS AND METHODS: Cells were cryopreserved with 10% dimethyl sulfoxide and different concentrations of FBS (10%, 40%, and 90%) with or without 0.2 M SUC, totaling six comparison groups. Non-cryopreserved cells were used as a control. Cells were evaluated for viability, metabolic activity, proliferative activity, reactive oxygen species (ROS), mitochondrial membrane potential and apoptosis levels. RESULTS: No difference was observed among cryopreserved with DMSO containing (10FBS, 10FBS-SUC, 40FBS, 40FBS-SUC, 90FBS, 90FBS-SUC) and non-cryopreserved groups for viability, metabolic activity, proliferative activity, and ROS levels. Interestingly, only cells cryopreserved with 90% FBS and SUC maintained the mitochondrial membrane potential like the control. This indicates that at high concentrations of FBS, SUC contributes to the maintenance of this parameter in cryopreserved cells. Moreover, at concentrations of 10% and 40% of FBS, SUC contributed to the maintenance of viability evaluated by the levels of apoptosis evaluated after thawing. In summary, we verified that 90% FBS and 0.2 M SUC promote greater ability of cells after thawing. Additionally, SUC positively acts in cryopreservation solutions containing 10% and 40% FBS. CONCLUSION: This information is essential to an understanding of the mechanisms involved in the interactions of extracellular cryoprotectants in somatic cell cryopreservation solutions of red-rumped agoutis. DOI: 10.54680/fr23210110212.


Assuntos
Criopreservação , Dasyproctidae , Animais , Bovinos , Criopreservação/veterinária , Sacarose/farmacologia , Espécies Reativas de Oxigênio , Crioprotetores/farmacologia , Dimetil Sulfóxido/farmacologia , Sobrevivência Celular
3.
Cryo Letters ; 44(1): 47-56, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36629841

RESUMO

BACKGROUND: Skin cryobanks represent important tools for the conservation of the maximum genetic representation of a population, especially those with a certain degree of threat to extinction, such as the ocelot. A relevant step towards the proper establishment of these banks is the definition of adequate cryopreservation techniques for the conservation of the skin. OBJECTIVE: We evaluated the effects of two different techniques [direct vitrification in cryovials (DVC) and solid-surface vitrification (SSV)] for the preservation of ear skin derived from ocelot. MATERIALS & METHODS: For both techniques, we vitrified the ear skin using Dulbeccos modified Eagles medium with 3.0 M dimethyl sulfoxide, 0.25 M sucrose, and 10% fetal bovine serum. Non-cryopreserved tissues were used as control (control group). All tissues were analyzed for their morphometric characteristics by conventional histology and morphological / functional analysis by cell ability during the culture. RESULTS: While tissues cryopreserved by DVC showed similar values for dermis thickness and number of perinuclear halos to the control, tissues cryopreserved by SSV showed similarities to the control regarding the number of melanocytes, percentage of collagen fibers, and numbers of viable cells by apoptosis analysis. Additionally, none of the vitrification techniques affected stratum corneum thickness, number of keratinocytes, tissue proliferative activity, cell viability, or metabolism. CONCLUSION: Both vitrification techniques (DVC and SSV) can be used for the conservation of ocelot skin; however, SSV guarantees a higher cellular quality after in vitro tissue culture in most of the parameters evaluated, such as viability, metabolism, and apoptosis analysis. doi.org/10.54680/fr23110110412.


Assuntos
Criopreservação , Vitrificação , Criopreservação/métodos , Crioprotetores/farmacologia , Dimetil Sulfóxido , Sacarose/farmacologia
4.
Public Health ; 207: 62-72, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35526358

RESUMO

OBJECTIVES: This study aimed to describe trends and patterns of cause-specific hospitalizations in mainland Portugal between 2000 and 2016. STUDY DESIGN: This was a retrospective observational study based on hospital discharge data during the period 2000-2016 in mainland Portugal. METHODS: All inpatient hospital discharges among mainland Portuguese public hospitals were considered to evaluate trends and patterns over the years through hospitalization proportions, number of hospitalizations, age-standardized hospitalization rates (direct standardization using the European standard population), and the number of in-hospital stay days (bed-days). Health Cost and Utilization Project Clinical Classifications Software was used to categorize and cluster inpatients' principal diagnosis. RESULTS: Between 2000 and 2002 and between 2014 and 2016, age-standardized hospitalization rates decreased by 8.6%. Moreover, "liveborn," "diseases of the heart," and "respiratory infections" were the leading hospitalization causes in both periods with a variation of -8.8%, -8.3%, and 13.4% on age-standardized hospitalization rate, respectively. The age-standardized hospitalization rate due to "bacterial infection" increased by 108.7%. "Respiratory diseases" are the leading cause responsible for more in-hospital stay days in the period 2014-2016 (48.6% increase). All Portuguese regions presented decreasing overall trends in their age-standardized hospitalization rates in the study period, yet increasing trends were observed until 2004 except for the Lisbon region; in addition, the number of in-hospital stay days remained relatively stable through time. CONCLUSIONS: Hospitalizations in mainland Portugal decreased between 2000 and 2016 with heterogeneous patterns considering time, age group, and gender. "Aspiration pneumonitis; food/vomitus," "diseases of the white blood cells," "other nutritional, endocrine, and metabolic disorders," "bacterial infection," and "pathological fractures" revealed substantial increases, and further evaluations and monitoring are required.


Assuntos
Hospitalização , Alta do Paciente , Humanos , Pacientes Internados , Tempo de Internação , Portugal/epidemiologia
5.
Eur J Appl Physiol ; 121(9): 2585-2594, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34097130

RESUMO

PURPOSE: To test the hypothesis that interval-training (IHT) would be impaired by hypoxia to a larger extent than repeated-sprint training (RSH) and that dietary nitrate (NO3-) would mitigate the detrimental effect of hypoxia to a larger extent during IHT than RSH. METHODS: Thirty endurance-trained male participants performed IHT (6 × 1 min at 90%∆ with 1 min active recovery) and RSH (2 sets of 6 × 10 s "all-out" efforts with 20 s active recovery) on a cycle ergometer, allocated in one of three groups: normobaric hypoxia (~ 13% FiO2) + NO3- - HNO, n = 10; normobaric hypoxia + placebo - HPL, n = 10; normoxia (20.9% FiO2) + placebo - CON, n = 10. Submaximal oxygen uptake ([Formula: see text]O2), time spent above 90% of maximal [Formula: see text]O2 (≥ 90 [Formula: see text]O2max) and heart rate (≥ 90 HRmax) were compared between IHT and RSH sessions and groups. Additionally, mean power output (MPO), decrement score and % of power associated with [Formula: see text]O2max (%p[Formula: see text]O2max) in RSH sessions were analyzed. RESULTS: [Formula: see text]O2 at sub-maximal intensities did not differ between training protocols and groups (~ 27 ml kg-1 min-1). ≥ 90 HRmax was significantly higher in IHT compared to RSH session (39 ± 8 vs. 30 ± 8%, p = 0.03) but only in HNO group. MPO (range 360-490 W) and decrement score (10-13%) were similar between groups although %p[Formula: see text]O2max was significantly higher (p = 0.04) in CON (166 ± 16 W) compared with both HPL (147 ± 15 W) and HNO (144 ± 10 W) groups. CONCLUSION: IHT responses were neither more impaired by hypoxia than RSH ones. Moreover, dietary NO3- supplementation impacted equally IHT and RSH training responses' differences between hypoxia and normoxia.


Assuntos
Suplementos Nutricionais , Treinamento Intervalado de Alta Intensidade , Hipóxia , Nitratos/administração & dosagem , Adulto , Desempenho Atlético/fisiologia , Humanos , Masculino , Consumo de Oxigênio/fisiologia
6.
J Dairy Sci ; 103(11): 10862-10866, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32921453

RESUMO

The aim of this study was to evaluate the potential negative effects of superovulation on subsequent fertility of dairy heifers. Holstein heifers (n = 1,783), 312 to 387 d of age, and 273 to 307 kg of body weight (BW) from 2 commercial farms were enrolled. These animals were first selected to be donors (446) or nondonors (CON, n = 1,327) according to their genomic values. Nondonor heifers (CON) were artificially inseminated (AI) according to standard procedures of each farm after reaching 320 kg of BW. Donor heifers were superovulated using a fixed FSH dose (180 mg NIH-FSH-P1; Folltropin-V, Vetoquinol Brasil, Mairiporã, SP, Brazil) and embryos were collected following standard procedures. Heifers that produced fewer than 8 viable embryos after first superovulation (SOV1, n = 337) were no longer used as donors, whereas the remaining heifers (SOV2, n = 109) were superovulated a second time within an interval of 48 to 54 d. Donor heifers (SOV1 and SOV2) were AI once they reached 320 kg of BW, at least 15 d after the last embryo collection. Data on age at first AI, at conception, and at parturition, as well as the number of services per conception, were analyzed by ANOVA, using the PROC MIXED procedure of SAS (SAS Institute Inc., Cary, NC) procedure. Binomial variables (pregnancy per AI, overall pregnancy rate, open heifers at 500 d age, and late pregnancy loss) were analyzed using the GLIMMIX procedure of SAS. The heifers selected to undergo superovulation twice (SOV2) yielded more total (12.6 ± 5.3 vs. 6.8 ± 4.6; respectively) and viable embryos (8.5 ± 3.8 vs. 3.9 ± 2.8; respectively) than those superovulated only once (SOV1). Age at first AI, conception, and at parturition was greater in SOV2, but not in SOV1 compared with nondonor controls. In addition, pregnancy per first AI, overall pregnancy rate, services per conception, open heifers at 500 d of age, and occurrence of pregnancy losses after 60 d of gestation were similar among CON, SOV1, and SOV2 heifers. In summary, a single superovulation performed before heifers reach a minimum weight for breeding did not affect age at conception, calving or other indicators of reproductive efficiency. On the other hand, heifers superovulated twice were first inseminated at a later age than their birth cohorts, but had similar reproductive performance.


Assuntos
Bovinos/fisiologia , Fertilidade , Superovulação/efeitos dos fármacos , Animais , Feminino , Hormônio Foliculoestimulante/administração & dosagem , Hormônio Foliculoestimulante/farmacologia , Inseminação Artificial/veterinária , Gravidez , Taxa de Gravidez
7.
Med Teach ; 42(9): 1051-1057, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32697116

RESUMO

BACKGROUND: Medical curricula have historically been designed in a top-down approach, usually excluding students. While Delphi panels have been used as a tool for medical education curricula design, none have been conducted in Ecuador. In addition, no such approach has ever included students both as panelists and researchers. MATERIAL AND METHODS: Four Delphi panels were developed and conducted using a participatory approach that allowed medical students to take part both as expert panelists and researchers: specifically, students developed the questionnaire and conducted a qualitative synthesis. Questionnaire responses were anonymized and dispatched online to panelists. The information was organized and collected to develop the qualitative syntheses and prepare the final statements. RESULTS: Thirty-two medical students participated between February and May 2018. A total of 32 questions were developed, corresponding to five different categories. For some questions, consensus was reached; for other questions, general statements were obtained.Discussion and conclusion: Developing the questionnaire, responding to it and analyzing the answers allowed students to raise significant concerns regarding medical education topics proposing relevant policy and curricula change. Participatory Delphi panels can be an efficient tool to obtain organized feedback, improve student class involvement, and promote research skills.


Assuntos
Educação de Graduação em Medicina , Educação Médica , Estudantes de Medicina , Currículo , Técnica Delphi , Equador , Humanos
8.
J Helminthol ; 94: e185, 2020 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-32907641

RESUMO

Fasciolosis is a food-borne disease that causes great distress to a range of hosts, including humans. The objectives of this study were to (1) evaluate the liver damage and carcass weight of cattle naturally infected with Fasciola hepatica from the state of Rio Grande do Sul (RS), Brazil, and to (2) determine the distribution of adult flukes in 12,236 cattle liver from RS. The data from these experiments were used to calculate the overall economic loss due to F. hepatica infection. Eighteen adult Polled Hereford cows were divided into a triclabendazole (TbG) and a F. hepatica-positive group (FhG). For Experiment 1, a generalized linear mixed model revealed a statistical difference in carcass weight (49.8 kg) between TbG and FhG. The Monte Carlo analysis also revealed that the animals' weight differences were due to the disease. For Experiment 2, the prevalence of infected livers was above 16% (1904/12,236), mostly (20.1%) from the south-west region of RS. The Susceptible-infected-recovered (SIR) epidemic model revealed the evolution of the infection using a high infectivity and low recovery rate. Other distinctive scenarios that occur in RS were also established with different rates of infectivity. The economic assessment showed a potential loss of US$45 million to the beef cattle industry of RS, with an overall State cost of US$90.3 million. These novel findings reveal the importance of fasciolosis infection, which can cause a significant health condition and poor animal welfare.


Assuntos
Doenças dos Bovinos/parasitologia , Simulação por Computador , Doenças Endêmicas/veterinária , Fasciolíase/epidemiologia , Fasciolíase/veterinária , Animais , Brasil/epidemiologia , Bovinos , Doenças dos Bovinos/economia , Doenças dos Bovinos/epidemiologia , Fasciola hepatica , Fasciolíase/economia , Feminino , Modelos Lineares , Fígado/parasitologia , Fígado/patologia , Método de Monte Carlo , Prevalência
9.
Transfus Med ; 28(6): 420-426, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30304760

RESUMO

OBJECTIVE: The aim of our work was to establish a semi-automated high-throughput DNA amplification method for the universal screening of bacteria in platelet concentrates (PCs). BACKGROUND: Among cases of transfusion transmission of infectious agents, bacterial contamination ranks first in the number of events, morbidity and mortality. Transmission occurs mainly by transfused PCs. Automated culture is adopted by some blood banks for screening of bacterial contamination, but this procedure is expensive and has a relatively long turnaround time. METHODS: PCs were spiked with suspensions of five different bacterial species in a final concentration of 1 and 10 colony-forming units (CFU) per millilitre. After incubation, the presence of bacteria was investigated by real-time polymerase chain reaction (PCR) and by the Enhanced Bacterial Detection System (eBDS, Pall) assay as a reference method. Real-time PCR amplification was performed with a set of universal primers and probes targeting the 16S rRNA gene. Co-amplification of human mitochondrial DNA served as an internal control. RESULTS: Using the real-time PCR method, it was possible to detect the presence of all bacterial species tested with an initial concentration of 10 CFU mL-1 24 h after contamination, except for Staphylococcus hominis. The PCR assay also detected, at 24 h, the presence of Serratia marcescens and Enterobacter cloacae with an initial concentration of 1 CFU mL-1 . CONCLUSIONS: The real-time PCR assay may be a reliable alternative to conventional culture methods in the screening of bacterial contamination of PCs, enabling bacterial detection even with a low initial concentration of microorganisms.


Assuntos
Bactérias/genética , Doadores de Sangue , Plaquetas/microbiologia , Genes de RNAr/genética , Técnicas de Amplificação de Ácido Nucleico , RNA Bacteriano/genética , RNA Ribossômico 16S/genética , Brasil , Humanos
10.
Artigo em Inglês | MEDLINE | ID: mdl-29655816

RESUMO

Reproduction is an essential process for life and is regulated by complex hormone networks and environmental factors. To date, little is known about the contribution of epigenetic mechanisms to the regulation of reproduction, particularly in lower vertebrates. We used the zebrafish (Danio rerio) model to investigate the sex-specific transcription and DNA methylation profiles for genes involved in the regulation of reproduction and in epigenetic signalling in the livers and gonads. We found evidence for associations between DNA promotor methylation and transcription for esr1 (gonads and female livers), amh (gonads) and dnmt1 (livers). In the liver, esr1 was shown to be significantly over-expressed in females compared to males, and its promoter was significantly hypo-methylated in females compared to males. In the gonads, genes involved in epigenetic processes including dnmt1, dnmt3 and hdac1 were over-expressed in the ovary compared to the testis. In addition, dnmt1 and dnmt3 transcription in the testis was found to be strongly correlated with global DNA methylation. These data provide evidence of the sex-specific epigenetic regulation and transcription of genes involved in reproduction and epigenetic signalling in a commonly used vertebrate model.


Assuntos
Metilação de DNA , Epigênese Genética , Fígado/metabolismo , Ovário/metabolismo , Fatores Sexuais , Testículo/metabolismo , Transcrição Gênica , Proteínas de Peixe-Zebra/genética , Peixe-Zebra/genética , Peixe-Zebra/fisiologia , Animais , Sequência de Bases , DNA (Citosina-5-)-Metiltransferase 1/genética , Receptor alfa de Estrogênio/genética , Feminino , Masculino , Regiões Promotoras Genéticas , Receptores de Peptídeos/genética , Receptores de Fatores de Crescimento Transformadores beta/genética , Reprodução
11.
Br Poult Sci ; 59(6): 624-628, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30141691

RESUMO

1. The aim of the following experiment was to estimate transgenerational epigenetic variance for egg quality traits using genealogical and phenotypic information in meat-type quail. Measured traits included egg length (EL) and width (EWD), albumen weight (AW), shell weight (SW), yolk weight (YW) and egg weight (EW). 2. A total of 391 birds were evaluated for egg quality by collecting a sample of one egg per bird, during three consecutive days, starting on the 14th d of production. Analyses were performed using mixed models including the random epigenetic effect. Variance components were estimated by the restricted maximum likelihood method. A grid-search for values for the auto-recursive parameter (λ) was used in the variance components estimation. This parameter is directly related to the reset (v) and epigenetic transmissibility (1 - v) coefficients. 3. The epigenetic effect was not significant for any of the egg quality traits evaluated. Direct heritability estimates for egg quality traits ranged in magnitude from 0.06 to 0.33, whereby the higher estimates were found for AW and SW. Epigenetic heritability estimates were low and close to zero (ranging from 0.00 to 0.07) for all evaluated traits. 4. The current breeding strategies accounting for additive genetic effect seem to be suitable for egg quality traits in meat-type quail.


Assuntos
Coturnix/genética , Ovos , Epigênese Genética/genética , Carne , Animais , Cruzamento/métodos , Feminino , Qualidade dos Alimentos , Variação Genética/genética , Masculino , Característica Quantitativa Herdável
12.
Clin Exp Immunol ; 189(3): 318-330, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28542701

RESUMO

Forkhead box P3 (FoxP3)+ regulatory T cells (Tregs ) are functionally deficient in systemic lupus erythematosus (SLE), characterized by reduced surface CD25 [the interleukin (IL)-2 receptor alpha chain]. Low-dose IL-2 therapy is a promising current approach to correct this defect. To elucidate the origins of the SLE Treg phenotype, we studied its role through developmentally defined regulatory T cell (Treg ) subsets in 45 SLE patients, 103 SLE-unaffected first-degree relatives and 61 unrelated healthy control subjects, and genetic association with the CD25-encoding IL2RA locus. We identified two separate, uncorrelated effects contributing to Treg CD25. (1) SLE patients and unaffected relatives remarkably shared CD25 reduction versus controls, particularly in the developmentally earliest CD4+ FoxP3+ CD45RO- CD31+ recent thymic emigrant Tregs . This first component effect influenced the proportions of circulating CD4+ FoxP3high CD45RO+ activated Tregs . (2) In contrast, patients and unaffected relatives differed sharply in their activated Treg CD25 state: while relatives as control subjects up-regulated CD25 strongly in these cells during differentiation from naive Tregs , SLE patients specifically failed to do so. This CD25 up-regulation depended upon IL2RA genetic variation and was related functionally to the proliferation of activated Tregs , but not to their circulating numbers. Both effects were found related to T cell IL-2 production. Our results point to (1) a heritable, intrathymic mechanism responsible for reduced CD25 on early Tregs and decreased activation capacity in an extended risk population, which can be compensated by (2) functionally independent CD25 up-regulation upon peripheral Treg activation that is selectively deficient in patients. We expect that Treg -directed therapies can be monitored more effectively when taking this distinction into account.


Assuntos
Família , Subunidade alfa de Receptor de Interleucina-2/genética , Lúpus Eritematoso Sistêmico/imunologia , Linfócitos T Reguladores/imunologia , Adulto , Idoso , Feminino , Citometria de Fluxo , Humanos , Interleucina-2/biossíntese , Interleucina-2/imunologia , Subunidade alfa de Receptor de Interleucina-2/imunologia , Antígenos Comuns de Leucócito/genética , Antígenos Comuns de Leucócito/imunologia , Antígenos Comuns de Leucócito/metabolismo , Lúpus Eritematoso Sistêmico/fisiopatologia , Ativação Linfocitária/imunologia , Masculino , Pessoa de Meia-Idade , Fenótipo , Linfócitos T Reguladores/classificação , Regulação para Cima , Adulto Jovem
13.
Reprod Fertil Dev ; 29(10): 1958-1970, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27997335

RESUMO

The aim of the present study was to characterise the roles of intrafollicular oestradiol production and granulosa cell (GC) expression of the LH receptor (LHR) gene and its isoforms during follicular deviation in Bos indicus. Follicular wave emergence was synchronised in heifers from a Bos taurus dairy (Holstein; n=10) and a B. indicus dairy breed (Gir; n=10). Follicles were aspirated individually at sizes corresponding to the periods of predeviation, deviation and postdeviation. Intrafollicular oestradiol (IF-E2) and progesterone (IF-P4) concentrations were determined in the follicular fluid (FF) by radioimmunoassay, and relative expression of P450 aromatase (CYP19A1) and LHR forms was evaluated in GC using real-time quantitative-polymerase chain reaction. Despite differences in the size of the dominant follicle at deviation, changes in CYP19A1 expression and IF-E2 concentrations were similar in follicles of the same diameter in both breeds. A peak in total LHR expression occurred after follicular deviation in association with low expression of LHR isoforms. The results suggest that regulation of LHR function by sequential changes in the expression pattern of LHR isoforms may play a role in the early deviation of the dominant follicle, as observed in B. indicus breeds.


Assuntos
Estradiol/biossíntese , Folículo Ovariano/metabolismo , Isoformas de Proteínas/metabolismo , Receptores do LH/metabolismo , Processamento Alternativo , Animais , Bovinos , Feminino , Líquido Folicular/metabolismo , Expressão Gênica , Progesterona/biossíntese , Isoformas de Proteínas/genética , Receptores do LH/genética
14.
Genet Mol Res ; 16(1)2017 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-28128404

RESUMO

Guaçatonga (Casearia sylvestris) is a native plant of the Atlantic Forest, with high medicinal potential and relevance for reforestation programs. The aim of this study was to characterize, with microsatellite markers, two populations of C. sylvestris from remaining areas of the Atlantic Forest in the State of São Paulo. High allelic variation was found in both populations (NA = 101 and 117; AR = 12.5 and 14.4), although with high endogamy coefficients (f = 0.640 and 0.363). Estimates of genetic structure suggested the presence of considerable genetic divergence between the populations (FST = 0.103); however, there was no spatial genetic structure within the populations. Genetic divergence may have occurred due to decreased gene flow between the fragmented populations as the result of deforestation. The results of this study demonstrate the importance of genetic diversity and its characterization in native plants within remaining forest areas for the management and restoration of such areas.


Assuntos
Casearia/genética , Florestas , Variação Genética , Genética Populacional , Repetições de Microssatélites
15.
Genet Mol Res ; 16(1)2017 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-28340274

RESUMO

Genomic selection (GS) is a variant of marker-assisted selection, in which genetic markers covering the whole genome predict individual genetic merits for breeding. GS increases the accuracy of breeding values (BV) prediction. Although a variety of statistical models have been proposed to estimate BV in GS, few methodologies have examined statistical challenges based on non-normal phenotypic distributions, e.g., skewed distributions. Traditional GS models estimate changes in the phenotype distribution mean, i.e., the function is defined for the expected value of trait-conditional on markers, E(Y|X). We proposed an approach based on regularized quantile regression (RQR) for GS to improve the estimation of marker effects and the consequent genomic estimated BV (GEBV). The RQR model is based on conditional quantiles, Qτ(Y|X), enabling models that fit all portions of a trait probability distribution. This allows RQR to choose one quantile function that "best" represents the relationship between the dependent and independent variables. Data were simulated for 1000 individuals. The genome included 1500 markers; most had a small effect and only a few markers with a sizable effect were simulated. We evaluated three scenarios according to symmetrical, positively, and negatively skewed distributions. Analyses were performed using Bayesian LASSO (BLASSO) and RQR considering three quantiles (0.25, 0.50, and 0.75). The use of RQR to estimate GEBV was efficient; the RQR method achieved better results than BLASSO, at least for one quantile model fit for all evaluated scenarios. The gains in relation to BLASSO were 86.28 and 55.70% for positively and negatively skewed distributions, respectively.


Assuntos
Cruzamento/métodos , Genômica/métodos , Modelos Genéticos , Locos de Características Quantitativas , Animais , Teorema de Bayes , Marcadores Genéticos/genética , Genótipo , Polimorfismo de Nucleotídeo Único , Valor Preditivo dos Testes , Análise de Regressão , Seleção Genética
20.
Genet Mol Res ; 15(2)2016 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-27323104

RESUMO

The aim of this study was to screen for variability in the luteinizing hormone/choriogonadotropin receptor (LHCGR) and to determine the occurrence of LHCGR mRNA isoforms in two dairy breeds of cattle. Granulosa cells from dominant ovarian follicles were recovered from 16 Gir and 16 Holstein cows, and total RNA was extracted. Complementary DNA was synthesized and PCR was used to generate amplicons for sequencing. Chromatograms were evaluated, and multiple sequences were aligned and analyzed for the presence of polymorphisms, allele frequency, polymorphic information content (PIC), and Hardy-Weinberg equilibrium (HWE). Twenty-one single nucleotide polymorphisms (SNPs) were identified in LH receptor mRNA. Seventeen SNPs were identified in Gir cattle (seven exclusively), and 14 were found in Holstein cattle (four exclusively). Seven of the 21 polymorphisms found did not alter which amino acid was translated. Eight SNPs caused a change to an amino acid in a different chemical group. Classification of SNPs according to PIC values identified 12 as being highly informative in Gir cattle and five in Holstein. Eight SNPs deviated from HWE in Gir compared with 11 in Holstein, and eight in both breeds. Two isoforms were also identified, one in exon 1, which lacks 30 nucleotides beginning at position 118, and the other in exon 10. Taken together, these data show that LHCGR in dairy cattle breeds has a high frequency of polymorphism and exists in multiple isoforms resulting from alternative splicing.


Assuntos
Processamento Alternativo , Bovinos/genética , Polimorfismo de Nucleotídeo Único , Receptores do LH/genética , Animais , Feminino
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