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1.
Cell Reprogram ; 2020 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-32673062

RESUMO

Wnt/ß-Catenin signaling pathway plays an important role in maintaining self-renewal and pluripotency of human and mouse embryonic stem cells (ESCs). Activation of Wnt/ß-Catenin signaling pathway by glycogen synthase kinase-3 (GSK3) inhibitor, the Wnt signaling agonist, could maintain the pluripotency of human and mouse ESCs in the presence of serum. However, the role of signaling pathway in the derivation of buffalo ESCs remains unclear. In this study, we used GSK3 inhibitors (6-bromoindirubin-3'-oxime [BIO] and CHIR99021) and investigated the effect of Wnt/ß-Catenin activation on colony formation, proliferation, self-renewal, and pluripotency of Chinese swamp buffalo (buffalo) embryonic stem cell-like cells (ES-like cells), which were isolated from blastocysts. The results showed that buffalo ES-like cells displayed typical morphological characteristics of pluripotent stem cells: positive for alkaline phosphatase staining, expression of pluripotent markers, including OCT4, SOX2, SSEA-1, SSEA-4, LIN28, CH1, NANOG, and the proliferative markers, PCNA and C-MYC. Furthermore, activation of Wnt/ß-Catenin signaling pathway by GSK3 inhibitors could promote colony formation and proliferation of buffalo ES-like cells and maintain their undifferentiated state, and upregulate the expression levels of pluripotent-related genes and proliferation-related genes. These results indicated that Wnt/ß-Catenin signaling pathway plays an important role in the derivation and pluripotency of buffalo ES-like cells.

2.
Workplace Health Saf ; : 2165079920914923, 2020 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-32469688

RESUMO

Background: Percutaneous injuries and blood-borne-related infections pose occupational hazards to healthcare professionals. However, the prevalence and associated factors for these hazards among midwives in Hunan Province, China are poorly documented. Methods: A cross-sectional study was conducted among a sample of 1,282 eligible midwives in the cities of Yongzhou, Chenzhou, Hengyang, and Changsha in Hunan Province, China, from January 2017 to July 2017. The association of selected independent variables with percutaneous injuries was investigated using binary logistic regression. Results: 992 participants responded (77.3%), and within the previous 12 months, 15.7% experienced percutaneous injuries. In multivariate analysis, hospital size, age, length of employment as a midwife, weekly working hours, and three aspects of Hospital Safety Climate Scale were associated with percutaneous injuries. The risk of percutaneous injuries among the midwives working in hospitals with ≤399 beds was higher than that among those working in hospitals with ≥400 beds by nearly 3 times. Furthermore, the percutaneous injury prevalence of midwives decreased as age increased. Moreover, the probability of percutaneous injuries among the midwives with weekly working hours of >40 was 4.35 times higher compared with that among midwives with weekly working hours of ≤40. Conclusion/Application to practice: The prevalence of percutaneous injuries among midwives in the study hospitals was substantial. Our results further proved that risk mitigation strategies tailored to midwives are needed to reduce this risk. These strategies include ensuring a positive organizational climate, providing highly safe devices, and reducing the workload.

3.
BMC Genet ; 21(1): 23, 2020 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-32122301

RESUMO

BACKGROUND: Buffalo milk is considered as a highly nutritious food owing to its higher contents of fatty acids (FA) and rich nutrient profile. Higher fat contents of buffalo milk make it suitable for processing to develop various healthy and nutritious products. Moreover, buffalo milk contains more unsaturated FAs (UFA) such as oleic and linolenic acid, which are important from the human health point of view owing to their desirable physiological effects. However, inadequate information is available about the chemical composition and mechanism of FA synthesis in buffalo milk. In this study, we hypothesized that expression of SCD1 gene could alter the biosynthesis of FA in epithelial cells of mammary gland and subsequently affect the FA contents in buffalo milk. We investigated the transcriptional and biological role of Stearoyl-CoA Desaturase 1 (SCD1) in the buffalo mammary epithelial cells (BMECs) during FA and triacylglycerol (TAG) synthesis. RESULTS: Results revealed that unsaturated fatty acid contents were much higher in concentration in buffalo milk as compared to Holstein cow. Significant increase in the expression level of FAS, ACACA, SREBP1, PPARG, GPAT, and AGPAT genes was observed in response to altered expression of SCD1 in buffalo milk. Moreover, change in SCD1 gene in BMECs also mediated the expression of genes related to FA biosynthesis subsequently leading to alter the FA composition. Overexpression of SCD1 significantly increased the expression of genes associated with FA and TAG synthesis leading to enhance FA and unsaturated FA contents in BMECs. However, down-regulation of SCD1 exhibited opposite consequences. CONCLUSION: Our study provides mechanistic insights on transcriptional regulation of SCD1 to alter FA and TAG synthesis through directly or indirectly mediating biosynthesis and metabolic pathways in BMECs. We provide preliminary findings regarding engineering of FA contents in buffalo milk through SCD1 signaling.

4.
Theriogenology ; 130: 79-88, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30877846

RESUMO

Brain-derived neurotrophic factor (BDNF) has been discovered and characterized for several decades, yet its expression pattern in non-neuronal tissues like ovary and potential mechanism during oocyte maturation are still poorly understood. Thus the present study was devised to determine the expression pattern and mechanism of BDNF during buffalo oocyte maturation. The results revealed that BDNF was presented at different stages of buffalo ovarian follicles as well as during oocyte maturation and early embryo development. BDNF's receptor p75 was detected in granulosa cells, cumulus cells, oocytes, and early embryos, while another receptor neurotrophic tyrosine kinase receptor, type2 (NTRK2) was only identified in granulosa cells and cumulus cells. To determine the effect of BDNF on oocyte maturation and early embryo development, different concentrations (0, 1, 10, 100 ng/mL) of BDNF were added into the in vitro maturation media, respectively. It was divulged that 10 ng/mL BDNF promoted the in vitro maturation rate of buffalo oocytes and the blastocysts rate of embryos cultured in vitro (P < 0.05). Then through using NTRK2 inhibitor K-252a, we found BDNF and its receptor NTRK2 in cumulus cells played an essential role during oocyte maturation. Moreover, to further investigate the underlying mechanism by which BDNF enhances oocyte maturation, RT-qPCR was performed. 10 ng/mL BDNF treatment could decrease the expression level of apoptosis-related genes CCASP9, FAS, up-regulate the expression level of receptor gene NTRK2, cell proliferation-related genes CCNB1, PCNA, gap junction-related genes GJA4, GJA1 as well as cumulus cells expansion-related genes HAS2, PTX3 and TNFAIP6 (P < 0.05). Altogether, our results showed for the first time that BDNF was expressed throughout buffalo ovarian follicle development, oocyte maturation and early embryogenesis. Furthermore, BDNF treatment could improve the efficiency of buffalo oocyte maturation through regulating genes expression in cumulus cells and then promote early embryo development.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/metabolismo , Búfalos/embriologia , Técnicas de Maturação in Vitro de Oócitos/veterinária , Oócitos/fisiologia , Folículo Ovariano/metabolismo , Animais , Fator Neurotrófico Derivado do Encéfalo/efeitos dos fármacos , Fator Neurotrófico Derivado do Encéfalo/genética , Búfalos/fisiologia , Técnicas de Cultura Embrionária , Feminino , Oócitos/efeitos dos fármacos , Receptor de Fator de Crescimento Neural/genética , Receptor de Fator de Crescimento Neural/metabolismo , Receptor trkB/genética , Receptor trkB/metabolismo
5.
ACS Appl Mater Interfaces ; 11(8): 8138-8147, 2019 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-30714377

RESUMO

The regulation of oxidation levels is of great importance as an efficient way to optimize the thermoelectric (TE) performance of conducting polymers. Many efforts have been devoted to the acquisition of a high TE performance for poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) by oxidation/reduction post treatment to achieve an effective compromise. However, a strong oxidant/reductant is usually employed to tune the TE performance of PEDOT:PSS with high electrical conductivity (σ) and Seebeck coefficient ( S), and it also presents a number of operational challenges depending on a fast reaction rate. Herein, nontoxic polyethylenimine ethoxylated (PEIE) served as a reductant to successfully realize an enhanced S for PEDOT:PSS, besides playing a significant anion-blocking role in enabling the efficient modulation of the oxidation level by sulfuric acid (H2SO4) with a longer operating time. Eventually, a good PEDOT-rich nanocrystal is achieved by a sequential dipping process in PEIE/ethylene glycol and H2SO4 solutions. The large TE power factor of 133 µW m-1 K-2 can be ascribed to the good formation of PEDOT-rich nanocrystals and an effective compromise between σ and S of PEDOT:PSS films. A mechanism was elucidated for the efficient regulation of σ and S enabling high performance of organic TE materials.

6.
Reprod Domest Anim ; 54(2): 258-269, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30220080

RESUMO

The present study explored a suitable parthenogenetic activation (PA) procedure for rabbit oocytes and investigated the developmental potential of somatic cell nuclear transfer (SCNT) embryos using rabbit foetal fibroblasts (RFFs). The electrical activation had the optimal rate of blastocyst (14.06%) when oocytes were activated by three direct current (DC) pulses (40 V/mm, 20 µs each) followed by 6-dimethylaminopurine (6-DMAP) and cycloheximide (CHX) treatment; the blastocyst rate of ionomycin (ION) + 6-DMAP + CHX (12.07%) activation was higher than that of ION + 6-DMAP (8.6%) activation or ION + CHX (1.24%) activation; there was no significant difference in blastocyst rate between ION + 6-DMAP + CHX and DC + 6-DMAP + CHX groups. The blastocyst rate of ION + 6-DMAP + CHX-activated oocytes in the basic rabbit culture medium (M-199) + 10% foetal bovine serum (FBS; 14.28%) was higher than that in buffalo conditioned medium (5.75%) or G1/G2 medium (0), and the blastocyst rate was increased when M-199 + 10% FBS was supplemented with amino acids. Refreshing culture medium every day or every other day significantly increased the blastocyst rate. Treatment of donor cells with 0.5% FBS for 3-5 days increased blastocyst rate of SCNT embryos (33.33%) than no serum starvation (22.47%) or 0.5% FBS treatment for 6-9 days (23.61%); the blastocyst rate of SCNT embryos derived from nontransgenic RFFs was higher than that derived from transgenic RFFs by electroporation. The blastocyst development ability of SCNT embryos derived from RFFs by electroporation (32.22%) was higher than that of liposome (19.11%) or calcium phosphate (20.00%) transfection, and only the embryos from electroporation group have the EGFP expression (24.44%). In conclusion, this study for the first time systematically optimized the conditions for yield of rabbit embryo by SCNT.


Assuntos
Blastocisto/efeitos dos fármacos , Desenvolvimento Embrionário/efeitos dos fármacos , Técnicas de Transferência Nuclear/veterinária , Oócitos/efeitos dos fármacos , Partenogênese , Adenina/análogos & derivados , Adenina/farmacologia , Animais , Blastocisto/fisiologia , Cicloeximida/farmacologia , Desenvolvimento Embrionário/fisiologia , Feminino , Ionomicina/farmacologia , Oócitos/fisiologia , Coelhos
7.
J Vet Med Sci ; 80(8): 1291-1300, 2018 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-29925699

RESUMO

The present study was undertaken to examine the effects of cytoplasmic volume on nucleus reprogramming and developmental competence of buffalo handmade cloning (HMC) embryos. We found that both HMC embryos derived from ~150% cytoplasm or ~225% cytoplasm resulted in a higher blastocyst rate and total cell number of blastocyst in comparison with those from ~75% cytoplasm (25.4 ± 2.0, 27.9 ± 1.6% vs. 17.9 ± 3.1%; 150 ± 10, 169 ± 12 vs. 85 ± 6, P<0.05). Meanwhile, the proportions of nuclear envelope breakdown (NEBD) and premature chromosome condensation (PCC) were also increased in the embryos derived from ~150 or ~225% enucleated cytoplasm compared to those from ~75% cytoplasm. Moreover, HMC embryos derived from ~225% cytoplasm showed a decrease of global DNA methylation from the 2-cell to the 4-cell stage in comparison with those of ~75% cytoplasm (P<0.05). Furthermore, the expression of embryonic genome activation (EGA) relative genes (eIF1A and U2AF) in HMC embryos derived from ~225% cytoplasm at the 8-cell stages was also found to be enhanced compared with that of the ~75% cytoplasm. Two of seven recipients were confirmed to be pregnant following transfer of blastocysts derived from ~225% cytoplasm, and one healthy cloned calf was delivered at the end of the gestation period, whereas no recipients were pregnant after the transfer of blastocysts derived from ~75% cytoplasm. These results indicate that the cytoplasmic volume of recipient oocytes affects donor nucleus reprogramming, and then further accounted for the developmental ability of the reconstructed embryos.


Assuntos
Búfalos , Clonagem de Organismos , Desenvolvimento Embrionário/fisiologia , Animais , Blastocisto , Búfalos/embriologia , Feminino , Fibroblastos , Técnicas de Transferência Nuclear , Oócitos , Gravidez
8.
Sci Rep ; 8(1): 6967, 2018 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-29725050

RESUMO

The possibility of producing transgenic cloned buffalos by nuclear transfer of fetal fibroblasts expressing enhanced green fluorescent protein (EGFP) was explored in this study. When buffalo fetal fibroblasts (BFFs) isolated from a male buffalo fetus were transfected with pEGFP-N1 (EGFP is driven by CMV and Neo is driven by SV-40) by means of electroporation, Lipofectamine-LTX and X-tremeGENE, the transfection efficiency of electroporation (35.5%) was higher than Lipofectamine-LTX (11.7%) and X-tremeGENE (25.4%, P < 0.05). When BFFs were transfected by means of electroporation, more embryos from BFFs transfected with pEGFP-IRES-Neo (EGFP and Neo are driven by promoter of human elongation factor) cleaved and developed to blastocysts (21.6%) compared to BFFs transfected with pEGFP-N1 (16.4%, P < 0.05). A total of 72 blastocysts were transferred into 36 recipients and six recipients became pregnant. In the end of gestation, the pregnant recipients delivered six healthy calves and one stillborn calf. These calves were confirmed to be derived from the transgenic cells by Southern blot and microsatellite analysis. These results indicate that electroporation is more efficient than lipofection in transfecting exogenous DNA into BFFs and transgenic buffalos can be produced effectively by nuclear transfer of BFFs transfected with pEGFP-IRES-Neo.


Assuntos
Animais Geneticamente Modificados/genética , Búfalos/genética , Feto/metabolismo , Fibroblastos/metabolismo , Proteínas de Fluorescência Verde/genética , Técnicas de Transferência Nuclear , Animais , Animais Geneticamente Modificados/embriologia , Blastocisto/citologia , Blastocisto/metabolismo , Búfalos/embriologia , Separação Celular , Células Cultivadas , Clonagem de Organismos/métodos , Eletroporação/métodos , Feminino , Feto/citologia , Fibroblastos/citologia , Humanos , Masculino , Gravidez , Transfecção/métodos
9.
Pest Manag Sci ; 74(11): 2555-2560, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29667309

RESUMO

BACKGROUND: Anticoagulant rodenticides have been widely used in rodent control in China for >30 years and resistant Norway rats have been reported. Mutations in the vitamin K epoxide reductase complex, subunit 1 (Vkorc1) gene can cause anticoagulant resistance in rodents. In this study, we analyzed the Vkorc1 polymorphisms of 681 Norway rats collected in Zhanjiang and Harbin Cities in China from 2008 to 2015 and evaluated the warfarin resistance frequency. RESULTS: Analysis revealed four mutations, including three not previously reported. Two new synonymous mutations, His68His and Leu105Leu, are not associated with warfarin resistance. One new nonsynonymous mutation, Ala140Thr, was found in Zhanjiang rat samples collected in 3 years with low frequencies (3.3-4.0%) and is probably associated with warfarin resistance. Laboratory resistance tests suggested low warfarin resistance frequencies in rats from Zhanjiang (4.9-17.1%) and Harbin (0-2.5%) Cities. CONCLUSIONS: Both genetic analysis and laboratory resistance tests suggested low warfarin resistance frequencies in rats from Zhanjiang and Harbin Cities. The alternate usage of first-generation anticoagulant rodenticides (FGARs) and second-generation anticoagulant rodenticides (SGARs) might represent an effective strategy against the development of warfarin resistance in Norway rats in China. © 2018 Society of Chemical Industry.


Assuntos
Resistência a Medicamentos/genética , Polimorfismo Genético/efeitos dos fármacos , Ratos/genética , Rodenticidas/farmacologia , Vitamina K Epóxido Redutases/genética , Varfarina/farmacologia , Animais , China , Cidades , Feminino , Masculino , Fatores de Tempo , Vitamina K Epóxido Redutases/metabolismo
10.
Theriogenology ; 91: 112-120, 2017 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-28215675

RESUMO

Primordial germ cells (PGCs) are destined to form gametes in vivo, and they can be reprogrammed into pluripotent embryonic germ (EG) cells in vitro. Buffalo PGC have been reported to be reprogrammed into EG-like cells, but the identities of the major signaling pathways and culture media involved in this derivation remain unclear. Here, the effects of basic fibroblast growth factor (bFGF) and downstream signaling pathways on the reprogramming of buffalo PGCs into EG-like cells were investigated. Results showed bFGF to be critical to buffalo PGCs to dedifferentiate into EG-like cells (20 ng/mL is optimal) with many characteristics of pluripotent stem cells, including alkaline phosphatase (AP) activity, expression of pluripotency marker genes such as OCT4, NANOG, SOX2, SSEA-1, CDH1, and TRA-1-81, and the capacity to differentiate into all three embryonic germ layers. After chemically inhibiting pathways or components downstream of bFGF, data showed that inhibition of the PI3K/AKT pathway led to significantly lower EG cell derivation, while inhibition of P53 activity resulted in an efficiency of EG cell derivation comparable to that in the presence of bFGF. These results suggest that the role of bFGF in PGC-derived EG-like cell generation is mainly due to the activation of the PI3K/AKT/P53 pathway, in particular, the inhibition of P53 function.


Assuntos
Búfalos/embriologia , Células Germinativas Embrionárias/efeitos dos fármacos , Fatores de Crescimento de Fibroblastos/farmacologia , Animais , Búfalos/crescimento & desenvolvimento , Búfalos/metabolismo , Técnicas de Cultura de Células/veterinária , Diferenciação Celular/efeitos dos fármacos , Linhagem da Célula , Reprogramação Celular , Células Germinativas Embrionárias/metabolismo , Células Germinativas Embrionárias/fisiologia , Sistema de Sinalização das MAP Quinases , Células-Tronco Pluripotentes , Transdução de Sinais
11.
Theriogenology ; 86(6): 1622-1629, 2016 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-27388808

RESUMO

Fetal fibroblasts are often used as donor cells for SCNT, but their short lifespan greatly limits this application. To provide stable and long-lifespan cells, buffalo fetal fibroblasts (BFFs) transfected with human telomerase reverse transcriptase (hTERT). The hTERT-transfected BFFs (hTERT-BFFs) were evaluated by qRT-PCR, Western blot, karyotype analysis, telomerase activity assay, growth curve assay, flow cytometry, and soft agar assay. The development of SCNT embryos derived from hTERT-BFFs was also assessed in vitro. The morphology of hTERT-BFFs was similar to the nontransfected BFFs, and the karyotype of hTERT-BFFs was normal at passage 30. The hTERT-BFFs at passage 4 and 30 had higher telomerase activity and extended proliferative lifespan with an increase in cell population at S phase when compared with nontransfected BFFs at passage 5 and 30. The mRNA expression of p53 in hTERT-BFFs at passage 5 and 30 remained unchanged when compared with nontransfected BFFs at passage 5, whereas the mRNA expression of p53 in the nontransfected BFFs at passage 30 was increased. Soft agar assay showed that hTERT-BFFs at passage 30 were not a malignant phenotype. Significantly, more SCNT embryos derived from hTERT-BFFs at passage 5 and 30 developed to blastocysts in comparison with BFFs at passage 30. The Caudal type homeobox 2 and Connexin 43 genes were indicated to involve in the development of cloned embryos. These results indicate that transfection of BFFs with hTERT can extend their lifespan and retain their basic and key biological characteristics in the status of primary BFFs.


Assuntos
Búfalos/embriologia , Clonagem de Organismos , Fibroblastos/enzimologia , Telomerase/genética , Transfecção/veterinária , Animais , Animais Geneticamente Modificados/embriologia , Blastocisto/fisiologia , Clonagem de Organismos/métodos , Desenvolvimento Embrionário , Feto/citologia , Expressão Gênica , Humanos , Técnicas de Transferência Nuclear , RNA Mensageiro/análise , Proteína Supressora de Tumor p53/genética
12.
Asian-Australas J Anim Sci ; 29(10): 1407-15, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26954139

RESUMO

Isolation and culture of spermatogonial stem cells (SSCs) are attractive for production of genetic modified offspring. In the present study, buffalo spermatogonial stem-like cells were isolated, cultured and expression pattern of different germ cell marker genes were determined. To recover spermatogonia, testes from age 3 to 7 months of buffalo were decapsulated, and seminiferous tubules were enzymatically dissociated. Two types of cells, immature sertoli cell and type A spermatogonia were observed in buffalo testes in this stage. Germ cell marker genes, OCT3/4 (Pou5f1), THY-1, c-kit, PGP9.5 (UCHL-1) and Dolichos biflorus agglutinin, were determined to be expressed both in mRNA and protein level by reverse transcription polymerase chain reaction and immunostaining in buffalo testes and buffalo spermatogonial stem-like cells, respectively. In the following, when the isolated buffalo buffalo spermatogonial stem-like cells were cultured in the medium supplemented 2.5% fetal bovine serum and 40 ng/mL glial cell-derived neurotrophic factor medium, SSCs proliferation efficiency and colony number were significantly improved than those of other groups (p<0.05). These findings may help in isolation and establishing long term in vitro culture system for buffalo spermatogonial stem-like cells, and accelerating the generation of genetic modified buffaloes.

13.
Nano Lett ; 16(1): 314-9, 2016 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-26645364

RESUMO

We report the controlled nanomorphology of semiconducting polymers on chemically and mechanically stable nanogrooved polymer substrates. By employing silicon dioxide thin films with finely adjusted thicknesses on nanogrooved polymer substrates, semiconducting polymer thin films oriented and aligned along the nanogrooves were obtained. Organic field-effect transistors (OFETs) fabricated from the oriented semiconducting polymer, poly[4-(4,4-dihexadecyl-4H-cyclopenta[1,2-b:5,4-b']dithiophen-2-yl)-alt-[1,2,5]thiadiazolo-[3,4-c]pyridine] (PCDTPT), yielded saturation hole mobilities as high as 19.3 cm(2) V(-1 )s(-1), and the flexible "plastic" transistors demonstrated excellent mechanical stability under various bending conditions. These results represent important progress for solution-processed flexible OFETs and demonstrate that directed self-assembly of semiconducting polymers can be achieved by soft nanostructures.

14.
Adv Mater ; 27(47): 7759-65, 2015 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-26499293

RESUMO

The determination of the band structure along k parallel to the chain direction demonstrates significant electronic delocalization. The small effective mass [m* = 0.106mo ] is consistent with the high measured mobility.


Assuntos
Elétrons , Polímeros/química , Semicondutores , Tiadiazóis/química , Solubilidade
15.
Chem Commun (Camb) ; 51(77): 14489-92, 2015 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-26279265

RESUMO

The racemic conglomerate (1P-NH3 + 1M-NH3) and enantioenriched bulk samples (1P-H2O or 1M-NH3) of Co(II) metal­organic frameworks were obtained from achiral precursors under different solvothermal conditions. The bulk homochirality was generated through asymmetrical crystallization in the absence of any chiral additives confirmed by single crystal X-ray diffraction and CD spectroscopy.


Assuntos
Cobalto/química , Compostos Orgânicos/química , Cristalização , Estereoisomerismo
16.
Cell Reprogram ; 17(5): 404-14, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26035741

RESUMO

The present study was undertaken to examine the effect of Scriptaid treatment on histone acetylation, DNA methylation, expression of genes related to histone acetylation, and development of buffalo somatic cell nuclear transfer (SCNT) embryos. Treatment of buffalo SCNT embryos with 500 nM Scriptaid for 24 h resulted in a significant increase in the blastocyst formation rate (28.2% vs. 13.6%, p<0.05). Meanwhile, treatment of buffalo SCNT embryos with Scriptaid also resulted in higher acetylation levels of H3K18 and lower methylation levels of global DNA at the blastocyst stage, which was similar to fertilized counterparts. The expression levels of CBP, p300, HAT1, Dnmt1, and Dnmt3a in SCNT embryos treated with Scriptaid were significantly lower than the control group at the eight-cell stage (p<0.05), but the expression of HAT1 and Dnmt1a was higher than the control group at the blastocyst stage (p<0.05). When 96 blastocysts developed from Scriptaid-treated SCNT embryos were transferred into 48 recipients, 11 recipients (22.9%) became pregnant, whereas only one recipient (11.1%) became pregnant following transfer of 18 blastocysts developed from untreated SCNT embryos into nine recipients. These results indicate that treatment of buffalo SCNT embryos with Scriptaid can improve their developmental competence, and this action is mediated by resulting in a similar histone acetylation level and global DNA methylation level compared to in vitro-fertilized embryos through regulating the expression pattern of genes related to histone acetylation and DNA methylation.


Assuntos
Búfalos/embriologia , Metilação de DNA/efeitos dos fármacos , Desenvolvimento Embrionário/efeitos dos fármacos , Inibidores de Histona Desacetilases/farmacologia , Hidroxilaminas/farmacologia , Técnicas de Transferência Nuclear , Quinolinas/farmacologia , Acetilação , Animais , Blastocisto/efeitos dos fármacos , Blastocisto/metabolismo , Búfalos/metabolismo , Proteína de Ligação a CREB/efeitos dos fármacos , Proteína de Ligação a CREB/genética , DNA (Citosina-5-)-Metiltransferase 1 , DNA (Citosina-5-)-Metiltransferases/efeitos dos fármacos , DNA (Citosina-5-)-Metiltransferases/genética , Feminino , Expressão Gênica , Histona Acetiltransferases/efeitos dos fármacos , Histona Acetiltransferases/genética , Histonas/efeitos dos fármacos , Histonas/metabolismo , Gravidez
17.
Nano Lett ; 14(5): 2764-71, 2014 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-24712578

RESUMO

Solution processable semiconducting polymers with excellent film forming capacity and mechanical flexibility are considered among the most progressive alternatives to conventional inorganic semiconductors. However, the random packing of polymer chains and the disorder of the polymer matrix typically result in low charge transport mobilities (10(-5)-10(-2) cm(2) V(-1) s(-1)). These low mobilities compromise their performance and development. Here, we present a strategy, by utilizing capillary action, to mediate polymer chain self-assembly and unidirectional alignment on nanogrooved substrates. We designed a sandwich tunnel system separated by functionalized glass spacers to induce capillary action for controlling the polymer nanostructure, crystallinity, and charge transport. Using capillary action, we demonstrate saturation mobilities with average values of 21.3 and 18.5 cm(2) V(-1 )s(-1) on two different semiconducting polymers at a transistor channel length of 80 µm. These values are limited by the source-drain contact resistance, Rc. Using a longer channel length of 140 µm where the contact resistance is less important, we measured µh = 36.3 cm(2) v(-1) s(-1). Extrapolating to infinite channel length where Rc is unimportant, the intrinsic mobility for poly[4-(4,4-dihexadecyl-4H-cyclopenta[1,2-b:5,4-b']dithiophen-2-yl)-alt-[1,2,5]thiadiazolo[3,4-c]pyridine] (Mn = 140 kDa) at this degree of chain alignment and structural order is µh ≈ 47 cm(2 )v(-1) s(-1). Our results create a promising pathway toward high performance, solution processable, and low-cost organic electronics.

18.
Int J Mol Sci ; 15(2): 2596-607, 2014 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-24534805

RESUMO

RNA polymerase III (pol III) type 3 promoters, such as 7SK and U6, are routinely used to induce short hairpin RNAs (shRNAs) to knockdown gene expression by RNA interference (RNAi). To extend the application of RNAi to studies of buffalo, an shRNAs expressing system using the buffalo pol III promoters was developed. Buffalo 7SK promoter (bu7SK) and U6 promoter (buU6) sequences upstream of the full-length 7SK and U6 small nuclear RNA sequence in the buffalo genome were identified and characterized, respectively. To determine the functionality of these promoters in constructs driving shRNA expression, anti-EGFP shRNAs (shEGFP) cassettes under the direction of bu7SK and buU6 were constructed. We further compared the EGFP knockdown efficiency of constructs using bu7SK and buU6 with that of promoters of human and bovine origins in BFF cells and mouse PT67 cells by flow cytometry and quantitative real-time PCR assays. We found that the bu7SK and buU6 promoters induced the greatest level of suppression in homologous and heterologous cells relative to promoters derived from other species. Taken together, functional bu7SK and buU6 promoters were identified and characterized, thus laying the groundwork for future development of RNAi therapeutics and gene modification in buffalo species.


Assuntos
RNA Polimerase III/genética , RNA Interferente Pequeno/metabolismo , RNA Nuclear Pequeno/metabolismo , Animais , Sequência de Bases , Búfalos , Bovinos , Linhagem Celular , Proteínas de Fluorescência Verde/antagonistas & inibidores , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Humanos , Camundongos , Regiões Promotoras Genéticas , Interferência de RNA , RNA Polimerase III/metabolismo , RNA Nuclear Pequeno/genética , Alinhamento de Sequência , Sítio de Iniciação de Transcrição
19.
Adv Mater ; 26(19): 2993-8, 2014 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-24504475

RESUMO

A record high OFET hole mobility, as high as 23.7 cm(2) /Vs, is achieved in macroscopic aligned semiconducting polymers. The high mobility is insensitive to the polymer molecular weight. Polymer chains are aligned along the fiber to facilitate intrachain charge transport.

20.
Theriogenology ; 80(8): 878-86, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24007823

RESUMO

It has been reported that buffalo (Bubalus bubalis) embryos reconstructed by somatic cell nucleus transfer (SCNT) can develop to the full term of gestation and result in newborn calves. However, the developmental competence of reconstructed embryos is still low. Recently, it has been reported that treating donor cells or embryos with trichostatin A (TSA) can increase the cloning efficiency in some species. Thus, the present study was undertaken to improve the development of buffalo SCNT embryos by treatment of donor cells (buffalo fetal fibroblasts) with TSA and explore the relation between histone acetylation status of donor cells and developmental competence of SCNT embryos. Treatment of donor cells with either 0.15 or 0.3 µM TSA for 48 hours resulted in a significant increase in the cleavage rate and blastocyst yield of SCNT embryos (P < 0.05). Meanwhile, the expression level of HDAC1 in donor cells was also decreased (0.4-0.6 fold, P < 0.05) by TSA treatment, although the expression level of HAT1 was not affected. Further measurement of the epigenetic maker AcH4K8 in buffalo IVF and SCNT embryos at the eight-cell stage revealed that the spatial distribution of acH4K8 staining in SCNT embryos was different from the IVF embryos. Treatment of donor cells with TSA resulted in an increase in the AcH4K8 level of SCNT embryos and similar to fertilized counterparts. These results suggest that treatment of donor cells with TSA can facilitate their nucleus reprogramming by affecting the acetylated status of H4K8 and improving the in vitro development of buffalo SCNT embryos. The AcH4K8 status at the eight-cell stage can be used as an epigenetic marker for predicting the SCNT efficiency in buffalos.


Assuntos
Búfalos/fisiologia , Transferência Embrionária/veterinária , Desenvolvimento Embrionário/efeitos dos fármacos , Ácidos Hidroxâmicos/farmacologia , Acetilação , Animais , Búfalos/embriologia , Técnicas de Cultura Embrionária/veterinária , Perfilação da Expressão Gênica , Histonas/metabolismo , Técnicas de Transferência Nuclear/veterinária , Reação em Cadeia da Polimerase em Tempo Real
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