RESUMO
The giant panda (Ailuropoda melanoleuca) is one of the world's most endangered mammals, and it has evolved several unusual biological and behavioral traits. During puberty, pregnancy, lactation, and involution, the mammary gland undergoes profound morphological and functional changes. A large number of microRNAs (miRNAs) have been identified to be involved in mammary gland development and lactation. In this study, we identified 202 conserved mature miRNAs, corresponding to 147 pre-miRNAs, in giant panda peripheral blood using a small RNA-sequencing approach. In addition, 27 miRNA families and 29 miRNA clusters were identified. We analyzed the arm selection preference of pre-miRNAs and found that: 1) most giant panda pre-miRNAs generated one-strand miRNAs, and the 5p-arm only miRNAs have a higher expression level than 3p-arm only miRNAs; 2) there were more 5p-arm dominant miRNAs than 3p-arm dominant miRNAs; and 3) 5p-arm dominant miRNAs have a larger fold change within miRNA pairs than 3p-arm dominant miRNAs. Expression of 12 lactation-related miRNAs was detected across late pregnancy and early lactation stages by qPCR, and seven miRNAs were identified as clustered in one significant model. Most of these clustered miRNAs exhibited inhibitory roles in proliferation and differentiation of mammary epithelial cells. Functional analysis highlighted important roles of the seven as signed miRNAs in mammary development and metabolic changes, including blood vessel morphogenesis, macromolecule biosynthesis, cell cycle regulation, and protein transport.
Assuntos
Lactação/genética , Glândulas Mamárias Animais/fisiologia , MicroRNAs/sangue , Prenhez/genética , Ursidae/genética , Animais , Feminino , Perfilação da Expressão Gênica/veterinária , Glândulas Mamárias Animais/metabolismo , MicroRNAs/genética , Gravidez , Prenhez/sangue , Reação em Cadeia da Polimerase em Tempo Real , Análise de Sequência de RNA/métodos , Maturidade Sexual/genética , Ursidae/sangueRESUMO
Hypoxia influences many physiological processes, such as respiration, cardiovascular, neurophysiology, and digestion. Skeletal muscle is an important motor organ, which relies on oxygen of oxidation; however, the study of hypoxia in skeletal muscle is lacking. In order to understand the effect of hypoxia on skeletal muscle, we determined the expression level of four hypoxia-related genes (ADAM17, ARG2, MMP, and HIF1A) in two distinct skeletal muscle tissues from Tibetan pigs that live at different altitudes (500 and 3650 m). Consistent with the well-characterized role of four hypoxia-related genes in the adaptation to high altitude, we found that, compared with the plain pigs, the plateau pigs had higher mRNA abundances of the four genes and lower myofiber ratio in skeletal muscle. The negative correlation between the myofiber ratio and mRNA abundance of the four hypoxia-related genes highlights their critical roles in skeletal muscle. These findings may be important for understanding skeletal muscle adaptation to high altitude and hypoxia-related muscle diseases in humans.
Assuntos
Altitude , Regulação da Expressão Gênica , Hipóxia/genética , Músculo Esquelético/metabolismo , Sus scrofa/genética , Animais , Feminino , Fibras Musculares Esqueléticas/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismoRESUMO
DNA methylation is a stable epigenetic mark mediating gene expression. Methylation is crucial for diverse biological processes, including aging and embryo development. FASN (fatty acid synthase) plays an important role in de novo lipogenesis, through catalyzing the reductive synthesis of long-chain fatty acids. In this study, we investigated the FASN gene expression pattern and corresponding DNA methylation status in the inner layer of backfat from Jinhua pigs at different developmental stages. Our results showed that FASN gene expression increases with age and is positively associated with adipocyte volume (r = 0.98, P < 0.01). In addition, the DNA methylation level for the first exon (0.11, CGI 3) of the FASN gene is approximately 8-fold lower than levels for its promoter (0.94, CGI 1&2) (two-way ANOVA, PCGI < 0.01). The association analysis revealed that both promoter (r = -0.944, P < 0.01) and first exon methylation (r = -0.774, P < 0.01) are significantly and negatively correlated with FASN gene expression. Our results will benefit future investigations of the epigenetic mechanism underlying FASN gene expression.
Assuntos
Metilação de DNA , Éxons , Ácido Graxo Sintase Tipo I/genética , Suínos/genética , Tecido Adiposo , Animais , Epigenômica , Ácidos Graxos/genética , Regulação da Expressão Gênica , Lipogênese , Regiões Promotoras GenéticasRESUMO
Parentage analysis and individual identification are recent, promising methods that have been applied to evolutionary and ecological studies, as well as conservation management. Parental exclusion relying on polymorphic microsatellites has been used worldwide in parentage determination, while the low mutation rate and genotyping error rate of single nucleotide polymorphisms (SNPs) make them another important marker for pedigree tracing. Here, we compared the effectiveness of microsatellites and SNP markers in European pigs. We also measured and presented the minimum and optimal criteria for SNP markers to be used in paternity and identity analysis. Our findings may contribute to the development of techniques for future molecular evolution and conservation studies, as well as breeding programs.
Assuntos
Repetições de Microssatélites/genética , Polimorfismo de Nucleotídeo Único , Sus scrofa/genética , Animais , Cruzamento , Europa (Continente) , Feminino , Frequência do Gene , Genótipo , Masculino , Modelos Genéticos , Linhagem , Probabilidade , Análise de Sequência de DNARESUMO
The spotted babylon, Babylonia areolata, is one of the most extensively cultured marine mollusks in southeast Asia. Eight polymorphic microsatellite markers were developed for this species, from a microsatellite-enriched library. These markers, characterized in 32 individuals from a hatchery population, were polymorphic, with allele numbers ranging from 6 to 18 per locus, expected and observed heterozygosities ranging from 0.68 to 0.94 and 0.56 to 0.81, respectively. One locus (HUBA09) showed significant deviation from Hardy-Weinberg equilibrium, probably due to the presence of null alleles. These microsatellite loci should be useful for future population genetic studies and marker-assisted breeding in this species.
Assuntos
DNA/genética , Gastrópodes/genética , Repetições de Microssatélites , Alelos , Animais , Sudeste Asiático , Cruzamento , Primers do DNA/genética , Loci Gênicos , Biblioteca Genômica , Técnicas de Genotipagem , Heterozigoto , Polimorfismo Genético , Análise de Sequência de DNARESUMO
BACKGROUND: The efficacy of micronutrient supplementation on growth may be modified by specific gastrointestinal parasite infections. METHODS: We carried out a double-blind placebo-controlled trial to evaluate the effect of vitamin A and zinc supplementation on gastro-intestinal pathogen infections and growth among 584 infants in Mexico City. Children aged 5-15 months were assigned to receive either a vitamin A supplement every 2 months (20,000 IU of retinol for infants < or =; 1 year or 45,000 IU for infants >1 year), a daily supplement of 20 mg of zinc, a combined vitamin A-zinc supplement or a placebo, and were followed up for 1 year. Weight and length were measured once a month and morbidity histories were recorded twice a week for 12 months. Monthly stool samples were screened for Giardia duodenalis, Ascaris lumbricoides and Entamoeba spp. Growth velocity slopes, generated from the linear regression of individual child length, and height-for-age z-scores on time were analyzed as end points in regression models, adjusting for the presence of parasite infections. RESULTS: The main effect of vitamin A supplementation was in height improvement (P<0.05), and was only found in the model evaluating infants with any parasite. There was an interaction effect of slower growth (P<0.05) found in infants infected with any parasite and supplemented with vitamin A in slower growth (P<0.05). In addition, the interaction of zinc supplementation and Giardia duodenalis or A. lumbricoides was associated with reduced growth (P<0.05). CONCLUSION: Gastro-intestinal parasite infections may modify the effect that zinc or vitamin A supplementation has on childhood growth.
Assuntos
Estatura/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Crescimento/efeitos dos fármacos , Enteropatias Parasitárias/complicações , Vitamina A/farmacologia , Zinco/farmacologia , Animais , Ascaríase/complicações , Ascaris lumbricoides , Estatura/fisiologia , Peso Corporal/fisiologia , Suplementos Nutricionais , Disenteria Amebiana/complicações , Fezes/parasitologia , Feminino , Giardíase/complicações , Crescimento/fisiologia , Transtornos do Crescimento/etiologia , Transtornos do Crescimento/prevenção & controle , Humanos , Lactente , Masculino , México , Oligoelementos/farmacologia , Vitaminas/farmacologiaRESUMO
In Chiapas, Mexico, diarrheal disease causes the majority of all deaths in children under the age of five. Treatment of childhood diarrhea may be influenced by local beliefs and cultural practices. Few studies have attempted to quantitatively evaluate health seeking behavior (HSB) for diarrheal diseases in indigenous communities, while controlling for potential confounding factors such as parental education or socioeconomic status. A rapid ethnographic survey was conducted in Nabenchauc, Chiapas, to determine hypothetical HSB patterns for each of four major types of childhood diarrhea. Additionally, we examined the actual HSB for the last episode of childhood diarrheal illness within the household. One hundred households participated in the survey; 94 households with children < 5 years old reported a mean of 1.9 diarrheal episodes during the preceding month. Households reported using a mean of 1.3 types of in-home remedies. Oral rehydration therapy (ORT) was used in <2% of the 368 HSB patterns elicited for the four types of diarrhea. HSB patterns utilized an eclectic combination of traditional, allopathic, local and distant health care options. A mean of 2.5 outside-the-home health care options were reported for each diarrheal type; the local grocery store was reported in 245 (67%) of the hypothetical HSB patterns and as a first option in 199 (54%). Maternal and/or paternal education had little impact on hypothetical HSB. Households with lower SES were more likely to report using local grocery stores as a first option and were less likely to use options outside the village. The rapid ethnographic survey approach allows for assessment of changes in the approach to health care option utilization in cultures incorporating new health care paradigms. Public health interventions targeting local stores may lead to increased use of ORT, thereby potentially reducing early morbidity and mortality due to childhood diarrhea.
Assuntos
Diarreia/terapia , Cuidado Periódico , Indígenas Norte-Americanos , Aceitação pelo Paciente de Cuidados de Saúde/etnologia , Adulto , Criança , Diarreia/etnologia , Feminino , Hidratação , Humanos , Masculino , México , População RuralRESUMO
OBJECTIVE: Determine the impact of dietary risk factors on patterns of infection by heat labile toxin-producing Escherichia coli (LT-ETEC). MATERIALS AND METHODS: Ninety-eight infants were followed from birth for one year in Guadalajara, Mexico, beginning in august of 1986. Stool and breast milk samples were collected weekly from infants and their mothers, respectively. Mothers were also interviewed on a weekly basis regarding the health of the infants. Parametric hazard models were fit to durations of different LT-ETEC disease states determined through the analysis of stools. The child's consumption of supplemental foods and liquids as well as specific levels of LT-ETEC-specific breast milk antibodies were included in each model as time-varying covariates. RESULTS: The hazard of LT-ETEC asymptomatic infection increased 400 percent among children who received oats gruel (hazard rate = 4.01; 95% CI 2.77-5.24). The duration of infection was reduced if the child had had a previous LT-ETEC diarrheal episode (2.12; 95% CI 1.74-2.49) but was prolonged if the child consumed herbal teas (0.53; 95% CI 0.27-0.7). Herbal teas and high LT-ETEC-specific breast milk antibody levels each reduced the hazard of symptomatic infection by ninety percent. Symptomatic episodes became asymptomatic more rapidly if a child was given rice water. CONCLUSIONS: Specific weaning foods increase the risk of infection. Breastmilk antibodies and liquid infusions reduce diarrheal disease and infection duration.
Assuntos
Aleitamento Materno , Diarreia Infantil/epidemiologia , Infecções por Escherichia coli/epidemiologia , Métodos de Alimentação , Alimentos Infantis , Aleitamento Materno/estatística & dados numéricos , Diarreia Infantil/etiologia , Diarreia Infantil/microbiologia , Escherichia coli/isolamento & purificação , Infecções por Escherichia coli/etiologia , Infecções por Escherichia coli/microbiologia , Fezes/microbiologia , Métodos de Alimentação/estatística & dados numéricos , Humanos , Lactente , Alimentos Infantis/estatística & dados numéricos , Recém-Nascido , México/epidemiologia , Leite Humano/microbiologia , Modelos de Riscos Proporcionais , Fatores de Risco , Fatores de TempoRESUMO
Ninety-eight women-infant pairs were followed for up to 50 weeks in the northern part of Guadalajara, Mexico, from August 1986 to July 1987 as part of a community-based, prospective study of the relation between infant feeding patterns and enterotoxigenic Escherichia coli producing heat-labile toxin (LT-ETEC) diarrheal disease. Strictly formula-fed children had an incidence of diarrhea over three times that of strictly breast-fed infants and twice that of breast-fed and supplementally fed children. Strictly formula-fed infants colonized by LT-ETEC were symptomatic for diarrhea nearly three times as often as strictly breast-fed infants and twice as often as infants receiving a mixed diet. The fitting of parametric hazard models to durations until LT-ETEC colonization revealed that the hazard for the first colonization was time invariant. The hazard of diarrhea increased by 400-500% during the rainy season or among children 3 months of age or older who received avena, a barley drink. The best-fitting hazard models to durations until symptomatic expression of LT-ETEC infection all increased through time. This hazard was inversely impacted by the overall amount of LT-ETEC-specific, immunoglobulin A antibodies the infant received via the mother's breast milk and by the provision of traditional medicinal teas.