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1.
bioRxiv ; 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-36778461

RESUMO

Radical cure of Plasmodium vivax malaria must include elimination of quiescent 'hypnozoite' forms in the liver; however, the only FDA-approved treatments are contraindicated in many vulnerable populations. To identify new drugs and drug targets for hypnozoites, we screened the Repurposing, Focused Rescue, and Accelerated Medchem (ReFRAME) library and a collection of epigenetic inhibitors against P. vivax liver stages. From both libraries, we identified inhibitors targeting epigenetics pathways as selectively active against P. vivax and P. cynomolgi hypnozoites. These include DNA methyltransferase (DNMT) inhibitors as well as several inhibitors targeting histone post-translational modifications. Immunofluorescence staining of Plasmodium liver forms showed strong nuclear 5-methylcystosine signal, indicating liver stage parasite DNA is methylated. Using bisulfite sequencing, we mapped genomic DNA methylation in sporozoites, revealing DNA methylation signals in most coding genes. We also demonstrated that methylation level in proximal promoter regions as well as in the first exon of the genes may affect, at least partially, gene expression in P. vivax. The importance of selective inhibitors targeting epigenetic features on hypnozoites was validated using MMV019721, an acetyl-CoA synthetase inhibitor that affects histone acetylation and was previously reported as active against P. falciparum blood stages. In summary, our data indicate that several epigenetic mechanisms are likely modulating hypnozoite formation or persistence and provide an avenue for the discovery and development of improved radical cure antimalarials.

2.
Zhonghua Yu Fang Yi Xue Za Zhi ; 56(1): 25-28, 2022 Jan 06.
Artigo em Chinês | MEDLINE | ID: mdl-35092986

RESUMO

The ex vivo biosensor assay is developed to assess the health effects and toxicological mechanism of environmental pollutants with internal environment homeostasis changes by integrating the in vivo exposure evaluation, in vitro outcomes analysis, and systematic environment component screening. This toxicology testing model combines the real-world exposure of people in the field and the study of molecular mechanism exploration in lab experiments to overcome the shortcomings of a single toxicology method. It provides a new technique and perspective for toxicity testing and risk assessment in mesoscale between macroscopic population study and microscopic mechanism exploration.


Assuntos
Técnicas Biossensoriais , Poluentes Ambientais , Poluentes Ambientais/toxicidade , Humanos , Medição de Risco , Testes de Toxicidade
3.
Zhonghua Liu Xing Bing Xue Za Zhi ; 38(9): 1165-1168, 2017 Sep 10.
Artigo em Chinês | MEDLINE | ID: mdl-28910924

RESUMO

Objective: To investigate the prevalence of HIV, HBV and HCV infections in children aged 1-13 years in Yi ethnic area in Sichuan province. Methods: A cross-sectional study was conducted in the form of field survey in four townships selected from Yi ethnic area of Sichuan during 2014-2015. Participants were children aged 1-13 years by sample size of 900 and were screened for HIV antibody, HBV surface antigen and HCV antibody, and laboratory comfirmation was conducted. The area, age, gender and ethnic group specific infection rates were compared by using Fisher's exact test, and multiple comparisons were corrected by using Bonferroni correction. Results: A total of 677 children aged 1-13 years were surveyed. The infection rates of HIV, HBV and HCV were 1.03% (7/677, 95%CI: 0.42%-1.12%), 6.65% (45/677, 95%CI: 4.89%-8.79%) and 0.15% (1/677, 95%CI: 0%-0.82%), respectively. The infection rates of HIV differed among townships (P=0.000), the infection rate was higher in township D than in township B, the difference was significant (P<0.001). The differences in HIV infection rate among different age, gender and ethnic groups were not significant. The differences in HBV and HCV infections were not significant among different townships, age, gender and ethnic groups. The difference in HBV viral load between age group 5-9 years and age groups 10-13 years was not significant (U=115.000, P=0.967). Conclusions: The burden of HIV and HBV infections in children aged 1-13 years was heavy in rural area of Yi ethnic area in Sichuan. Therefore, it is necessary to take effective measures to block the vertical transmission of HIV and HBV as well as to increase the coverage of HBV vaccination.


Assuntos
Etnicidade/estatística & dados numéricos , Infecções por HIV/epidemiologia , Hepatite B/epidemiologia , Hepatite C/epidemiologia , Adolescente , Criança , Pré-Escolar , China/epidemiologia , Estudos Transversais , Infecções por HIV/etnologia , Hepatite B/etnologia , Hepatite C/etnologia , Humanos , Lactente , Prevalência , População Rural , Inquéritos e Questionários
4.
Zhonghua Liu Xing Bing Xue Za Zhi ; 38(6): 837-840, 2017 Jun 10.
Artigo em Chinês | MEDLINE | ID: mdl-28647993

RESUMO

Both HIV and HBV infection have become major health problems, of global concern, due to the high prevalence in the past few decades. Data from cumulated epidemiological surveys have shown the links between maternal HIV or HBV infection and adverse outcomes on pregnancy. Maternal HIV or HBV infection may also increase the mother-to-child (MTCT) transmission of the two diseases. However, association between HIV-HBV co-infection and adverse pregnancy is still inconclusive. Does maternal HIV-HBV co-infection have an impact on mother-to-child transmission on either HIV or HBV? Study on effective precautionary measures to promote both maternal and child's health is deemed necessary.


Assuntos
Infecções por HIV/epidemiologia , Hepatite B/epidemiologia , Transmissão Vertical de Doenças Infecciosas , Complicações Infecciosas na Gravidez/virologia , Resultado da Gravidez/epidemiologia , Adulto , Coinfecção , Feminino , Infecções por HIV/transmissão , Infecções por HIV/virologia , Hepatite B/transmissão , Hepatite B/virologia , Humanos , Mães , Gravidez , Prevalência , Estudos Soroepidemiológicos
5.
Transgenic Res ; 24(1): 61-71, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25063310

RESUMO

Competition between humans and livestock for cereal and legume grains makes it challenging to provide economical feeds to livestock animals. Recent increases in corn and soybean prices have had a significant impact on the cost of feed for pig producers. The utilization of byproducts and alternative ingredients in pig diets has the potential to reduce feed costs. Moreover, unlike ruminants, pigs have limited ability to utilize diets with high fiber content because they lack endogenous enzymes capable of breaking down nonstarch polysaccharides into simple sugars. Here, we investigated the feasibility of a transgenic strategy in which expression of the fungal cellulase transgene was driven by the porcine pancreatic amylase promoter in pigs. A 2,488 bp 5'-flanking region of the porcine pancreatic amylase gene was cloned by the genomic walking technique, and its structural features were characterized. Using GFP as a reporter, we found that this region contained promoter activity and had the potential to control heterologous gene expression. Transgenic pigs were generated by pronuclear microinjection. Founders and offspring were identified by PCR and Southern blot analyses. Cellulase mRNA and protein showed tissue-specific expression in the pancreas of F1 generation pigs. Cellulolytic enzyme activity was also identified in the pancreas of transgenic pigs. These results demonstrated the establishment of a tissue-specific promoter of the porcine pancreatic amylase gene. Transgenic pigs expressing exogenous cellulase may represent a way to increase the intake of low-cost, fiber-rich feeds.


Assuntos
Animais Geneticamente Modificados/genética , Celulase/genética , Transgenes , Ração Animal , Animais , Animais Geneticamente Modificados/metabolismo , Fungos/enzimologia , Fungos/genética , Humanos , alfa-Amilases Pancreáticas/genética , Regiões Promotoras Genéticas , Sus scrofa
7.
Theriogenology ; 79(9): 1284-93, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23566670

RESUMO

The first successful rabbit SCNT was achieved more than one decade ago, yet rabbits remain one of the most difficult species to clone. The present study was designed to evaluate the effects of two histone deacetylase inhibitors (HDACis), namely trichostatin A (TSA) and scriptaid (SCP), on cloning efficiency in rabbits. The in vitro development, acetylation levels of histone H4 lysine 5 (H4K5), and octamer-binding transcription factor 4 (Oct-4) expression patterns of cloned embryos were systemically examined after various HDACi treatments. Supplementation of TSA (50 nM) or SCP (250 nM) in the culture medium for 6 hours improved blastocyst development rates of cloned embryos compared with the treatment without HDACi. The combined treatment with TSA (50 nM) and SCP (250 nM) further enhanced morula (58.6%) and blastocyst (49.4%) rates in vitro. More importantly, compared with single HDACi treatments, embryos with the combined treatment had a higher level of H4K5 and an increased total cell number (203.7 ± 14.4 vs. 158.9 ± 9.0 or 162.1 ± 8.2; P < 0.05) with a better Oct-4 expression pattern in hatching blastocysts, indicating substantially improved embryo quality. This was apparently the first report regarding Oct-4 expression in cloned rabbit embryos. We inferred that most cloned rabbit embryos had an aberrant inner cell mass (ICM) structure accompanied with abnormal spatial distribution of Oct-4 signals. This study demonstrated a synergistic effect of TSA and SCP treatments on cloned rabbit embryos, which might be useful to improve cloning efficiency in rabbits.


Assuntos
Técnicas de Cultura Embrionária/veterinária , Ácidos Hidroxâmicos/farmacologia , Hidroxilaminas/farmacologia , Quinolinas/farmacologia , Coelhos/embriologia , Animais , Clonagem de Organismos , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Masculino , Fator 3 de Transcrição de Octâmero/genética , Fator 3 de Transcrição de Octâmero/metabolismo
8.
Hong Kong Med J ; 18 Suppl 2: 27-30, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22311358

RESUMO

1. Human coronaviruses (HCoVs)were detected in 2.5% of 2982 local children hospitalised for acute respiratory infections in 2005 to 2007. 2. Using the 'pancoronavirus' reverse transcription-polymerase chain reaction assay, detection rates were 0.6% for HCoVNL63,1.2% for HCoV-OC43,0.5% for HCoV-HKU1, and 0.2% for HCoV-229E. Notably, HCoV-NL63 infections were significantly more common among children hospitalised in 2006/2007 (1.2%) than in 2005/2006 (0.3%).3. The peak season for HCoVNL63 infection was autumn(September to October). 4. HCoV-NL63 infection was associated with younger age,croup, febrile convulsion, and acute gastroenteritis. Such disease associations were not found with the other three HCoVs. 5. Most local HCoV-NL63 isolates were closely related to the prototype strain in Netherlands(NL496), but a few were phylogenetically distinct from the major cluster.


Assuntos
Infecções por Coronavirus/epidemiologia , Coronavirus Humano NL63/genética , Genes pol , Infecções Respiratórias/epidemiologia , Proteína C-Reativa/metabolismo , Criança , Pré-Escolar , Coronavirus Humano 229E/genética , Coronavirus Humano 229E/isolamento & purificação , Infecções por Coronavirus/diagnóstico , Coronavirus Humano NL63/isolamento & purificação , Coronavirus Humano OC43/genética , Coronavirus Humano OC43/isolamento & purificação , Feminino , Hong Kong/epidemiologia , Humanos , Lactente , Contagem de Leucócitos , Masculino , Neutrófilos , Filogenia , Infecções Respiratórias/diagnóstico , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Estações do Ano , Análise de Sequência de DNA
9.
Reprod Domest Anim ; 47(1): 69-81, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21599764

RESUMO

The survival and development of pre-implantation embryos are determinant factors affecting the outcome of animal reproduction. It is essential to transfer the expression of the genetic material from maternal sources, that is the ovum to the zygote before implantation to ensure successful development. Differentiation and transformation of blastomeres initiated during the morula and blastocyst stages is an important step of the embryonic development prior to implantation. We collected morula and early blastocyst samples from pure-bred Landrace pigs in vivo to study the differential gene expression patterns at these two stages. Total RNA was extracted from individual embryos and two rounds of amplification were employed. Two micrograms of antisense RNA, targets, were prepared and hybridized with each of four custom made oligo microarrays representing 24,000 porcine genes. The analyses of replicate hybridizations showed that among the 24,000 genes, 162 genes were expressed fivefold or greater in the morula compared to early blastocysts and 2126 genes were expressed fivefold or greater in early blastocysts compared to the morula. Of these differentially expressed genes, 1429 genes were functionally annotated with related human Gene Ontology terms. In addition to basic metabolic processes, genes related to signal transduction, transportation and cell differentiation were found in both stages and were up-regulated as embryo development proceeded. Real time polymerase chain reaction was utilized to quantify 12 genes differentially expressed in the 2 embryonic stages and validated the reliability of major evidences shown in microarrays. In conclusion, we have obtained a preliminary landscape of genes differentially expressed during the transition from morula to early blastocysts in pigs and showed a generally increased transcriptional activity, perhaps in preparation for implantation. Our results provide an opportunity to study the functions of these genes in relation to the development and survival of pre-implantation porcine embryos.


Assuntos
Blastocisto/metabolismo , Perfilação da Expressão Gênica/veterinária , Expressão Gênica , Mórula/metabolismo , Sus scrofa/embriologia , Animais , Análise de Sequência com Séries de Oligonucleotídeos , Reação em Cadeia da Polimerase em Tempo Real , Sus scrofa/genética
10.
Reprod Domest Anim ; 47(4): 553-61, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22044690

RESUMO

The aim of this article is to demonstrate and characterize caprine mammary epithelial cells (CMC) immortalized with human telomerase reverse transcriptase (hTERT) gene. Five immortalized CMCs were assigned to either myoepithelial or luminal epithelial groups based on their morphology and expression of cell lineage-specific intermediate filaments. Telomeric repeat amplification protocol revealed various telomerase activities in CMCs associated with their distinct proliferation potential. Karyotypic analysis showed three CMCs retained their modal Capra hircus chromosome number (2n = 60), whereas the remaining two CMCs were abnormal at 2n = 19 and 2n = 36. CMCs with abnormal karyotypes lost p53 protein after chemical-induced DNA damage and showed anchorage-independent growth in soft agar assay. In terms of functional differentiation, luminal CMCs organized into alveolus-like structures when grown in Matrigel. Furthermore, αs1- and ß-casein gene was induced in luminal CMCs in response to lacto-hormones stimulation. Together these results showed that hTERT-immortalized CMCs retained major characteristics of mammary epithelial cells, and stability of the genome is required for maintaining normal mammary epithelium function. Application of CMCs can provide valuable models to study alveologenesis and lactogenesis of mammary epithelium and test the feasibility of recombinant constructs designed for the generation of transgenic livestock.


Assuntos
Células Epiteliais , Cabras , Glândulas Mamárias Animais/citologia , Telomerase/genética , Animais , Ciclo Celular , Linhagem Celular Transformada , Células Cultivadas , Dano ao DNA , Células Epiteliais/enzimologia , Células Epiteliais/fisiologia , Células Epiteliais/ultraestrutura , Feminino , Expressão Gênica , Humanos , Cariotipagem/veterinária , Proteínas Recombinantes de Fusão/genética , Células-Tronco , Telômero/química , Transfecção
11.
J Dairy Sci ; 94(11): 5393-404, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22032362

RESUMO

The use of evaporative cooling for mitigating heat stress in lactating cows in humid areas is controversial. In Taiwan, Holstein cow performance is significantly restricted by hot and humid weather. This study investigated the efficacy of using a tunnel-ventilated, water-padded freestall (TP) barn for reducing heat stress in lactating cows. From August to October 2006, 36 cows allocated in a 3×3 Latin square were raised in 3 barn cooling treatments: a conventional freestall barn with fans and sprinklers in the feed line (Fan+SP, control), a TP barn, and a TP barn with sprinkler cooling (TP+SP). Daytime air speeds in the 3 barns were 1.23, 2.38, and 2.06 m/s, respectively. Both TP barns were more efficient than the control in reducing the daytime temperature and temperature-humidity index. The barn temperature was <26°C for an extra 4.2h per day, but the relative humidity was >96% in both TP barns. Cows in both TP barns had higher respiration rates and skin temperatures at 0300 h than cows in the Fan+SP barn. The TP environment increased the cows' serum cholesterol level and the activities of alkaline phosphatase and alanine aminotransferase, but blood partial pressure of CO(2) was not affected. Vaginal temperature was persistently high in cows in the TP barn; in the 2 SP barns, it decreased 0.4 to 0.6°C following sprinkling and milking. The intake activity and rumen digestion of cows raised in the 3 environments were similar. Cows in both TP barns ingested more dry matter. Cows in the TP+SP barn tended to produce more milk than those in the Fan+SP barn (25.4 vs. 24.7 kg). Although heat stress was not completely alleviated in these 3 barns, the TP+SP treatment resolved the negative effect of a previous TP barn built in 2004 on intake and milk yield by increasing air speed and using sprinkler cooling. Thus, it is expected that TP+SP barns will be beneficial in regions with high humidity. Adequate air speed and sprinkler cooling are likely to be key factors for further study.


Assuntos
Bovinos/fisiologia , Indústria de Laticínios , Transtornos de Estresse por Calor/veterinária , Abrigo para Animais , Umidade , Lactação/fisiologia , Ventilação , Animais , Temperatura Corporal , Indústria de Laticínios/instrumentação , Indústria de Laticínios/métodos , Ingestão de Alimentos/fisiologia , Feminino , Transtornos de Estresse por Calor/prevenção & controle , Temperatura , Ventilação/instrumentação , Ventilação/métodos , Água
12.
J Anim Sci ; 89(11): 3460-72, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21705633

RESUMO

The discovery of postnatal mesenchymal stem cells (MSC) with their general multipotentiality has fueled much interest in the development of cell-based therapies. Proper identification of transplanted MSC is crucial for evaluating donor cell distribution, differentiation, and migration. Lack of an efficient marker of transplanted MSC has precluded our understanding of MSC-related regenerative studies, especially in large animal models such as pigs. In the present study, we produced transgenic pigs harboring an enhanced green fluorescent protein (EGFP) gene. The pigs provide a reliable and reproducible source for obtaining stable EGFP-labeled MSC, which is very useful for donor cell tracking after transplantation. The undifferentiated EGFP-tagged MSC expressed a greater quantity of EGFP while maintaining MSC multipotentiality. These cells exhibited homogeneous surface epitopes and possessed classic trilineage differentiation potential into osteogenic, adipogenic, and chondrogenic lineages, with robust EGFP expression maintained in all differentiated progeny. Injection of donor MSC can dramatically increase the thickness of infarcted myocardium and improve cardiac function in mice. Moreover, the MSC, with their strong EGFP expression, can be easily distinguished from the background autofluorescence in myocardial infarcts. We demonstrated an efficient, effective, and easy way to identify MSC after long-term culture and transplantation. With the transgenic model, we were able to obtain stem or progenitor cells in earlier passages compared with the transfection of traceable markers into established MSC. Because the integration site of the transgene was the same for all cells, we lessened the potential for positional effects and the heterogeneity of the stem cells. The EGFP-transgenic pigs may serve as useful biomedical and agricultural models of somatic stem cell biology.


Assuntos
Animais Geneticamente Modificados/genética , Proteínas de Fluorescência Verde/genética , Células-Tronco Mesenquimais/citologia , Suínos/genética , Adipogenia/genética , Adipogenia/fisiologia , Animais , Animais Geneticamente Modificados/fisiologia , Diferenciação Celular/genética , Diferenciação Celular/fisiologia , Condrogênese/genética , Condrogênese/fisiologia , Ecocardiografia/veterinária , Feminino , Proteínas de Fluorescência Verde/metabolismo , Imuno-Histoquímica/veterinária , Transplante de Células-Tronco Mesenquimais/métodos , Transplante de Células-Tronco Mesenquimais/normas , Células-Tronco Mesenquimais/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Microscopia de Fluorescência/veterinária , Infarto do Miocárdio/terapia , Osteogênese/genética , Osteogênese/fisiologia , Distribuição Aleatória , Suínos/fisiologia
13.
J Anim Sci ; 89(8): 2407-14, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21421829

RESUMO

Amelogenin (AMEL) is a conserved gene located on the sex chromosomes of mammals. It is involved in the formation of enamel, which is the hard, white material that forms the protective outer layer of each tooth. In this study, we first cloned and determined the intron sequences of the goat AMELX and AMELY genes from female and male ear tissues. The polymorphic AMEL alleles were further analyzed by PCR-based RFLP and Southern blot hybridization analyses. Results showed that intron 5 nucleotide sequences of the goat AMELY gene contains multiple deletions/insertions and shares only 48.5% identity to intron 5 of the goat AMELX gene. Based on the polymorphic AMEL intron sequences, a set of sex-specific triplex primers was designed to PCR amplify a single fragment of 264 bp from the X chromosome of female goats and 2 fragments of 264 and 206 bp from the X and Y chromosomes, respectively, of male goats. An increased sensitivity for sex determination was reached with a single blastomere at the blastula stage isolated from goat embryos. A total of 43 goat embryos were used to estimate a 100% accuracy rate of this method confirmed by chromosomal karyotyping and live births. The embryo sexing technique has been successfully applied in different strains of goats including Alpine, Saanen, Nubian, and Taiwan goats.


Assuntos
Amelogenina/genética , Amelogenina/metabolismo , Cabras/embriologia , Cabras/genética , Cromossomo X/genética , Cromossomo Y/genética , Alelos , Animais , Sequência de Bases , Feminino , Masculino , Dados de Sequência Molecular , Reação em Cadeia da Polimerase/veterinária , Polimorfismo Genético , Análise de Sequência de DNA , Análise para Determinação do Sexo
14.
Med Mycol ; 49(1): 103-6, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20491531

RESUMO

Opportunistic yeast pathogens may switch from harmless commensal to pathogenic relationships with the host under different conditions. They usually cause superficial infections, but may be the agents of more significant infections in immunocompromised patients. To investigate yeast colonization in the oral cavities of clinically healthy individuals, we collected oral swabs from 323 students and staff at the National Health Research Institutes, Taiwan. A total of 49 (15.2%) volunteers were colonized by low levels of yeasts and of these, only 3 (6.1%) were co-colonized by more than one species. Among the 52 isolates, comprising seven fungal genera and 13 species, Candida albicans (57.7%) was the dominant species, followed by Candida parapsilosis (15.4%). There was only one isolate of C. parapsilosis that showed, in vitro, a high (2 µg/ml) minimum inhibitory concentration (MIC) to amphotericin B. There were six (11.5%) isolates with fluconazole MICs ≥ 64 µg/ml and all of them were non-Candida species. With the exception of Cryptococcus albidus, the remaining five isolates had voriconazole MICs ≥ 4 µg/ml. In addition, there was one C. albicans isolate with relatively high fluconazole (32 µg/ml) and voriconazole (4 µg/ml) MICs.


Assuntos
Portador Sadio/microbiologia , Boca/microbiologia , Leveduras/classificação , Leveduras/isolamento & purificação , Adolescente , Adulto , Anfotericina B/farmacologia , Antifúngicos/farmacologia , Feminino , Fluconazol/farmacologia , Experimentação Humana , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Pirimidinas/farmacologia , Taiwan , Triazóis/farmacologia , Voriconazol , Adulto Jovem
15.
Anim Reprod Sci ; 129(3-4): 162-70, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22225596

RESUMO

Effects of enucleation timing on enucleation rates, development and methylation levels of reconstructed bovine embryos were investigated. However, the enucleation rate of reconstructed embryos produced by the enucleation before fusion and activation (EBFA) was higher than that by the enucleation after fusion and activation (EAFA) procedure (80.7% vs. 59.1%, P<0.05). The blastocyst rate of reconstructed embryos cloned with ear fibroblasts in EBFA group was reduced (P<0.05) in comparison with that of EAFA group (24.6% vs. 34.4%). Two out of 11 recipients were pregnant and gave birth to two viable calves after transfer of 20 reconstructed EBFA embryos. Two out of seven recipients were pregnant and also gave birth to two calves, with one surviving, after transfer of 12 reconstructed embryos produced by EAFA procedure. Finally, the methylation level of satellite I gene of donor cells (69.8%) and reconstructed embryos in EBFA group (64.7%) were similar, which were both higher (P<0.05) than that of the reconstructed embryos in EAFA group (44.4%). The methylation level of satellite I gene of the reconstructed embryos in the IVF embryos (31.9%) was lower (P<0.05) than those in all other treatments. In conclusion, the reconstructed bovine embryos produced by the EAFA procedure revealed a better developmental competence with a lower methylation rate of satellite I gene than those produced by the EBFA procedure.


Assuntos
Clonagem de Organismos/métodos , Transferência Embrionária/métodos , Desenvolvimento Embrionário , Fertilização in vitro/métodos , Técnicas de Transferência Nuclear , Prenhez/metabolismo , Animais , Blastocisto/metabolismo , Bovinos , Metilação de DNA , DNA Satélite/genética , DNA Satélite/metabolismo , Feminino , Fibroblastos/metabolismo , Gravidez
16.
Theriogenology ; 74(9): 1587-95, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20708244

RESUMO

The objective of this study was to compare thermal sensitivity of recipient ooplasm and donor nucleus from Holstein and Taiwan native yellow (TY) cows. Oocytes and cumulus cells from each breed were incubated at 43 °C (heat shock) or 38.5 °C (control) for 1 h prior to nucleus transplantation. Reconstructed embryos cloned by transfer of non-heated Holstein donor cells to heat-shocked Holstein ooplasm (Ho(+)-Hd⁻) had a lower (P < 0.05) blastocyst rate than those cloned from non-heated Holstein ooplasm receiving heated (Ho⁻-Hd(+)) or non-heated (Ho⁻-Hd⁻) Holstein donor cells (11.3 vs. 34.3 or 36.8%). Heat-shocked donor cells from either Holstein or TY cows did not significantly affect blastocyst rates of reconstructed embryos produced from Holstein ooplasm (30.6-32.9%). In contrast, blastocyst rates of reconstructed embryos generated with heat-shocked Holstein ooplasm were lower (P < 0.05) than that with heat-shocked TY ooplasm (11.2 vs 45.2%). Without heat shock, embryos reconstructed by transferring donor cells to ooplasm of Holstein or TY cows had similar (P > 0.05) blastocyst rates (28.9-33.3%). Transplantation of reconstructed embryos (n = 30) to recipients (n = 23) resulted in three live calves, derived from embryos cloned with TY ooplasm and donor nuclei from either Holstein (n = 2) or TY cows (n = 1). In conclusion, ooplasm of TY cattle was more resistant to heat stress than that derived from Holsteins; therefore, ooplasm may be a major determinant for thermal sensitivity in bovine oocytes and embryos.


Assuntos
Bovinos/embriologia , Técnicas de Transferência Nuclear/veterinária , Temperatura , Animais , Bovinos/genética , Clonagem de Organismos/veterinária , Técnicas de Cultura Embrionária/veterinária , Transferência Embrionária/veterinária , Feminino , Oócitos/citologia , Estresse Fisiológico
17.
Cell Prolif ; 43(3): 235-48, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20546242

RESUMO

OBJECTIVES: Isolation of mouse mesenchymal stem cells (mMSCs), by the approach of plastic adherence, has been difficult due to persistent contamination by haematopoietic cells (HCs); we have observed that this contamination was due to engagement between HCs and mMSCs. The HCs can be lifted together with the mMSCs despite their insensitivity to trypsin digestion. Herein, we provide a single-step procedure to rapidly segregate mMSCs from HC contaminants using transient lower-density plastic adherence (tLDA). MATERIALS AND METHODS: The tLDA was performed by replating bone marrow adherent cells at lower density (1.25 x 10(4) cells/cm(2)) than usual, allowing for transient adherence of no more than 3 h, followed by trypsin digestion. tLDA-isolated cells were evaluated by immunophenotyping, multi-differentiation potentials, immunosuppressive properties, and therapeutic potential as demonstrated by symptoms of osteoporosis. RESULTS: The single-step tLDA method can effectively eliminate the persistent HC contaminants; tLDA-isolated cells were phenotypically equivalent to those reported as mMSCs. The isolated cells possessed classic tri-lineage differentiation potential into osteogenic, adipogenic and chondrogenic lineages and had immunosuppressive properties. After intravenous transplantation, they migrated into the allogeneic bone marrow and rescued hosts from osteoporosis symptoms, demonstrating their therapeutic potential. CONCLUSIONS: We have developed a simple and economical method that effectively isolates HC-free, therapeutically functional mMSCs from bone marrow cell adherent cultures. These cells are suitable for various mechanistic and therapeutic studies in the mouse model.


Assuntos
Transplante de Medula Óssea/métodos , Separação Celular/métodos , Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais/metabolismo , Animais , Antígenos de Superfície/análise , Antígenos de Superfície/metabolismo , Adesão Celular/fisiologia , Técnicas de Cultura de Células , Diferenciação Celular/fisiologia , Linhagem da Célula/fisiologia , Proliferação de Células , Células Cultivadas , Modelos Animais de Doenças , Feminino , Citometria de Fluxo/métodos , Imunofenotipagem , Células-Tronco Mesenquimais/citologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos ICR , Osteoporose/terapia , Plásticos/química , Tripsina/química
18.
J Anim Sci ; 88(10): 3233-41, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20562354

RESUMO

Visfatin is a visceral adipose tissue-specific adipocytokine that plays a positive role in attenuating insulin resistance by binding to the insulin receptor. Visfatin has been suggested to play a role in the regulation of lipid metabolism and inflammation; however, the mechanism remains unclear. We investigated the effects of visfatin on the regulation of gene expression in cultured porcine preadipocytes and differentiated adipocytes. In preadipocytes, the mRNA abundance of lipoprotein lipase and PPARgamma were significantly increased by visfatin or insulin treatment after 8 d (all P < 0.05). In the presence of insulin, the mRNA abundance of adipocyte fatty acid-binding protein was 24.7-fold greater than in the untreated group (P < 0.05), whereas visfatin alone had no effect on adipocyte fatty acid-binding protein mRNA abundance. Adipocyte differentiation was induced by insulin treatment for 8 d. In differentiated porcine adipocytes, exposure to insulin or visfatin for 24 h increased (P < 0.05) fatty acid synthase mRNA abundance but had no effect on the expression of sterol regulatory element binding-protein 1c mRNA. We also found a 5.8-fold upregulation of IL-6 expression in porcine adipocytes after 24 h of treatment with visfatin (P < 0.05). These results demonstrated that visfatin upregulated lipoprotein lipase expression in preadipocytes, potentially facilitating lipid uptake, and increased the gene expression of fatty acid synthase in differentiated adipocytes to potentially enhance lipogenic activity. Furthermore, visfatin can upregulate IL-6 expression in differentiated porcine adipocytes. The information presented in this study provides insights into the roles of visfatin in lipid metabolism in pigs.


Assuntos
Adipócitos/efeitos dos fármacos , Regulação Enzimológica da Expressão Gênica/genética , Metabolismo dos Lipídeos/efeitos dos fármacos , Nicotinamida Fosforribosiltransferase/fisiologia , Suínos/genética , Adipócitos/metabolismo , Animais , Células Cultivadas , Insulina/metabolismo , Metabolismo dos Lipídeos/genética , Lipase Lipoproteica/biossíntese , Lipase Lipoproteica/genética , PPAR gama/biossíntese , PPAR gama/genética , RNA Mensageiro/metabolismo , Proteínas Recombinantes/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa/veterinária , Proteína de Ligação a Elemento Regulador de Esterol 1/biossíntese , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo
19.
J Anim Sci ; 88(6): 2009-18, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20190170

RESUMO

Peroxisome proliferator-activated receptor delta promotes fatty acid catabolism and energy expenditure in skeletal muscle and adipose tissues. A ligand for PPARdelta is required to activate PPARdelta function. Polyunsaturated fatty acids are potential ligands for PPARdelta activation. The current experiment was designed to determine the potential for PUFA, particularly from dietary fish oil, to activate porcine PPARdelta in vivo. Transgenic mice were generated to overexpress porcine PPARdelta in the adipose tissue. Mice were fed a high-saturated fat (13% beef tallow), or high-unsaturated fat (13% fish oil) diet, or a diet containing 4 mg/kg of a PPARdelta ligand (L165041) for 4 mo. Compared with beef tallow feeding, fish oil feeding reduced fat mass and decreased (P < 0.05) plasma triacylglycerol and FFA concentrations in the transgenic mice. Adipose tissue expression of genes involved in adipogenesis (i.e., lipoprotein lipase and adipocyte fatty acid-binding protein) was decreased in transgenic mice fed fish oil or the PPARdelta ligand. In the same mice, expression of the lipolytic gene, hormone-sensitive lipase was increased (P < 0.05). Fish oil feeding also stimulated expression of genes participating in fatty acid oxidation in the liver of transgenic mice compared with wild-type mice. Overall, these results indicate that PUFA may serve as natural and effective regulators of lipid catabolism in vivo and many of these effects may be generated from activation of PPARdelta.


Assuntos
Tecido Adiposo/metabolismo , Gorduras Insaturadas na Dieta/metabolismo , Óleos de Peixe/metabolismo , Lipólise/fisiologia , PPAR delta/metabolismo , Adiponectina/genética , Adiponectina/metabolismo , Animais , Peso Corporal/fisiologia , Ingestão de Alimentos/fisiologia , Ácidos Graxos não Esterificados/sangue , Canais Iônicos/genética , Canais Iônicos/metabolismo , Ligantes , Lipase Lipoproteica/genética , Lipase Lipoproteica/metabolismo , Fígado/metabolismo , Camundongos , Camundongos Transgênicos , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo , Tamanho do Órgão/fisiologia , Fenoxiacetatos/farmacologia , RNA Mensageiro/química , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Esterol Esterase/genética , Esterol Esterase/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 1/genética , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Triglicerídeos/sangue , Proteína Desacopladora 3
20.
Med Mycol ; 48(2): 328-34, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20141372

RESUMO

To study the demographic changes of yeasts causing invasive infections in Taiwan, especially with respect to species distribution and antifungal susceptibility, we analyzed isolates obtained from four sterile sites of patients in 19 hospitals in 2002 (155 strains) and again from the same hospitals in 2006 (208 strains). Blood was the most common source of the yeasts, accounting for 73.8% of the total isolates, followed by ascites (21.5%), cerebrospinal fluid (3%), and synovia (1.7%). Candida albicans was the most frequently recovered species (50.1% of the total), followed by Candida tropicalis (20.7%), Candida glabrata (11.6%), Candida parapsilosis (8.5%), Cryptococcus neoformans (3.9%), Candida krusei (0.8%), and nine other species (4.3%). There were one (0.3%) and seven (1.9%) isolates with minimum inhibitory concentrations (MICs) of amphotericin B > or =2 mg/l after 24 h and 48 h incubation, respectively. In addition, there were 15 (4.3%) and 31 (8.6%) isolates with MICs of fluconazole > or =64 mg/l under the same conditions. The MIC(90) value of amphotericin B was 1 mg/l. The MIC(90) values of fluconazole were 4 mg/l after 24 h incubation and 32 mg/l after 48 h incubation. Interestingly, MICs for fluconazole > or =64 mg/l after 24 h were significantly higher for isolates obtained in 2006 than those in 2002 after 24 h (7.1% vs. 0.7%, p =0.009) and 48 h (13.5% vs. 2%, p =0.0003) incubations. The demographic difference between these two surveys is mainly due to one species, C. tropicalis.


Assuntos
Anfotericina B/farmacologia , Candida/efeitos dos fármacos , Candida/isolamento & purificação , Candidíase/microbiologia , Fluconazol/farmacologia , Antifúngicos/farmacologia , Candidíase/sangue , Candidíase/epidemiologia , Farmacorresistência Fúngica , Humanos , Testes de Sensibilidade Microbiana , Vigilância da População , Taiwan/epidemiologia
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