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1.
Ecotoxicol Environ Saf ; 259: 115002, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37201422

RESUMO

Multiple antibiotics that are used in veterinary medicine coexist in soils, but their interaction and the effects on adsorption and desorption in soils have not been extensively studied. In this study, using batch experiments, we evaluated the adsorption and desorption of sulfadiazine (SDZ), tetracycline (TC), and norfloxacin (NFX) using four different soil aggregate size fractions and discovered that: (1) TC had the highest adsorption (76-98 %) and the lowest desorption in each tested system, whereas SDZ showed opposite adsorption and desorption ability, (2) the highest adsorption and the lowest desorption of all three tested antibiotics were observed with soil macroaggregates (250-2000 µm) in all the cases; in contrast, opposite adsorption and desorption ability were observed for soil clay (<53 µm), and (3) adsorption of each antibiotic was in the following order: single system (71-89 %) > binary system (56-84 %) > ternary system (50-78 %); however, desorption were in the reverse order. The Freundlich equation fitting and Brunauer-Emmett-Teller (BET) analysis further demonstrated that the adsorption competition between the tested antibiotics depended mainly on the specific surface area of each soil aggregate size fractions and its chemical properties. In conclusion, soil macroaggregates play a key role in the retention of antibiotics in soils, and the coexistence of multiple antibiotics greatly increases leaching risk.


Assuntos
Antibacterianos , Poluentes do Solo , Antibacterianos/análise , Solo/química , Adsorção , Poluentes do Solo/análise , Tetraciclina/química , Sulfadiazina
2.
Ecotoxicol Environ Saf ; 232: 113281, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-35124422

RESUMO

The aim of this study was to characterize the effects of cornstalk biomass amendments on microbial communities in bauxite residues (BRs) by phylogenetic analysis. Improvements in soil geochemical, physical, and biological properties were assessed to identify the major factors controlling microbial community development in BRs. After one year of incubation, the salinity and structure of the amended BRs had gradually improved, with pH dropping from 11.39 to 9.89, the exchangeable sodium percentage (ESP) dropping from 86.3% to 35.2%, and the mean weight diameter (MWD) rising from 0.12 mm to 0.38 mm. Further analysis of community level physiological profiles (CLPP) showed that the microbial utilization of different carbohydrates had shifted significantly, in addition to increases in the diversity index H' (0.7-7.34), U (2.16-3.14), and the average well color development (0.059-1.08). Over the one-year outside incubation, the dominant fungal phyla in the BRs had shifted gradually from Ascomycota (85.64%) to Ascomycota (52.07%) and Basidiomycota (35.53%), while the dominant bacterial phyla had shifted from Actinobacteria (38.47%), Proteobacteria (21.39%), and Gemmatimonadetes (12.72%) to Actinobacteria (14.87%), Proteobacteria (23.53%), and Acidobacteria (14.37%). Despite these shifts, microbial diversity remained lower in the amended BRs than in the natural soil. Further redundancy analysis indicated that pH was the major factor driving shifts in the bacterial community, while aggregates were the major factor driving shifts in the fungal community. This study demonstrated that amendment with cornstalk biomass shifted the microbial community in the BRs from halophilic groups to acidogenic groups by improving the soil environmental conditions.


Assuntos
Microbiota , Microbiologia do Solo , Óxido de Alumínio/química , Biomassa , Filogenia , Solo/química
3.
Artigo em Inglês | MEDLINE | ID: mdl-34948992

RESUMO

Paddy soils are globally distributed and saturated with water long term, which is different from most terrestrial ecosystems. To better understand the environmental risks of antibiotics in paddy soils, this study chose sulfadiazine (SDZ) as a typical antibiotic. We investigated its adsorption behavior and the influence of soil solution properties, such as pH conditions, dissolved organic carbon (DOC), ionic concentrations (IC), and the co-existence of Cu2+. The results indicated that (1) changes in soil solution pH and IC lower the adsorption of SDZ in paddy soils. (2) Increase of DOC facilitated the adsorption of SDZ in paddy soils. (3) Cu2+ co-existence increased the adsorption of SDZ on organic components, but decreased the adsorption capacity of clay soil for SDZ. (4) Further FTIR and SEM analyses indicated that complexation may not be the only form of Cu2+ and SDZ co-adsorption in paddy soils. Based on the above results, it can be concluded that soil solution properties and co-existent cations determine the sorption behavior of SDZ in paddy soils.


Assuntos
Poluentes do Solo , Solo , Adsorção , Matéria Orgânica Dissolvida , Ecossistema , Poluentes do Solo/análise , Sulfadiazina
4.
Anim Biosci ; 34(12): 1879-1885, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33677911

RESUMO

OBJECTIVE: Owing to the lack of a breeding index for efficient and quick fertility evaluations of Holstein bulls when using traditional or genome-wide detection methods, this study aimed to determine whether in vitro fertilization (IVF) could be used as an indicator of conception rate of artificial insemination (AI). METHODS: Conventional and sexed frozen semen from nine bulls were used for IVF and AI. RESULTS: The IVF and AI conception rates of each bull were confirmed to be positively correlated between the conventional frozen and sexed frozen semen. The correlation coefficient R values of nine bulls between IVF and AI methods were 0.73 and 0.97 for the conventional frozen and sexed frozen semen, respectively. The average conception rate of three bulls undergoing AI was 69.5% and 64.2%, 61.8% and 58.8%, and 48.2% and 46.2% in first-, second-, and third-born cows when conventional frozen and sexed frozen semen were used, respectively, which showed a positive correlation with the fertilization rate in the same parity. We propose an evaluation standard to assess the fertilization ability of bulls based on their IVF test results, which is categorized into three grades: grade one, normal fertility bull with an AI conception rate of 40%±5% and IVF rate of 45% to 60%; grade two, higher fertility bull with an AI conception rate of 50%±5% and IVF rate of 61% to 80%; and grade three, highest fertility bull with an AI conception rate of 60%±5% and IVF rate of >80%. CONCLUSION: These findings reveal that IVF results can be used as a breeding index for bulls to evaluate their AI conception ability, which may shorten the time required to select bulls for breeding.

5.
J Exp Zool B Mol Dev Evol ; 334(4): 245-256, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32297418

RESUMO

Histone modifications play important roles in regulating chromatin dynamic changes. In this study, acetylated histone H3 lysine 9 and 18 (H3K9ac and H3K18ac), acetylated histone H4 lysine 5 and 8 (H4K5ac and H4K8ac), tri-methylation histone H3 lysine 4 (H3K4me3), di-methylation histone H3 lysine 9 (H3K9me2) are investigated in bovine oocytes, zygote, and preimplantation. During meiosis, H3K9ac and H3K18ac are erased after germinal vesicle breakdown, H4K8ac is erased after metaphase I (MI). Although H4K5ac is erased at MI, it is redetectable after this stage. However, histone methylations have no significant change during meiosis. During fertilization, intensive H4K5ac and H4K8ac are resumed on male and female chromatins at postfertilization 4 and 8 hr, respectively. H3K9ac and H3K18ac are resumed on both male and female chromatins at postfertilization 8 and 12 hr, respectively. H3K4me3 and H3K9me2 gradually increased on male chromatin after postfertilization 8 hr, while these two signals on female chromatin are detectable from postfertilization 2-18 hr. During embryo cleavage, H3K9ac, H3K18ac, and H3K4me3 are reduced at 8-cell stage, and then start to increase. H4K5ac, H4K8ac, and H3K9me2 increase after the 4-cell stage. At interphase, H4K5ac and H4K8ac are more intensive in nuclear periphery from 2- to 8-cell stages. During mitosis, the signal of H4K8ac is intensive at chromosome periphery. In summary, during both oocyte meiosis and fertilization, the dynamic changes of both histone acetylations and methylations happen in a process of lysine residue-specific and species-specific. During preimplantation development, the dynamic patterns of both H3K9ac and H3K18ac are similar to that of H3K4me3, while the dynamic pattern of H4K5ac is similar to that of H4K8ac. These results will be helpful for understanding the effect of histone posttranslational modifications on bovine reproduction and development.


Assuntos
Blastocisto/metabolismo , Bovinos/embriologia , Histonas/metabolismo , Oócitos/metabolismo , Zigoto/metabolismo , Acetilação , Animais , Fertilização , Humanos , Metilação
6.
Anim Reprod Sci ; 192: 44-52, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29526513

RESUMO

Ubiquitination is an important cellular process in spermatogenesis and involves the regulation of spermatid differentiation and spermiogenesis. In the current study, the correlation between bull sperm ubiquitination and sperm defects was analyzed, and the feasibility using anti-ubiquitin specific antibody immobilized magnetic beads to remove the spermatozoa with defects was assessed. A total of nine bulls were examined, and the amount of sperm ubiquitination ranged from 55 to 151. Correspondingly, the percentage of sperm deformity ranged from 9.3% to 28.1%. The coefficient of correlation was r = 0.92, indicating a significant correlation between the percentage of sperm deformity and the amount of ubiquitination (P < 0.05). The results from use of fluorescence staining and single-channel flow cytometry indicated there was a significant correlation between the sperm deformity and amount of ubiquitination (r = 0.86, P < 0.05). Results gained by use of the TUNEL and ubiquitination assays by double-channel flow cytometry indicated that the proportion of genetically defective spermatozoa with ubiquitination in Q3 and Q2 quartiles was markedly greater than that of spermatozoa with ubiquitination in Q1 and Q4 quartiles (82.1% compared with 17.9%). All these results confirmed that sperm ubiquitination is associated with genetic DNA defects (P < 0.01). Furthermore, nine semen samples with sperm motility of less than 50% (minimal motility), 50% to 70% (moderate motility) and greater than 70% (greatest motility) were selected for sorting defective spermatozoa using anti-ubiquitin specific antibody-coated magnetic beads. Strikingly, the percentage of sperm deformity significantly decreased from 18.8%, 19.0% and 17.1% to 11.7%, 11.0% and 11.0%, respectively (P < 0.05), suggesting that this method might be a feasible technology to improve the productivity via removal of the defective spermatozoa from bull semen.


Assuntos
Anticorpos , Manejo de Espécimes/veterinária , Espermatozoides/anormalidades , Animais , Bovinos , Dano ao DNA , Masculino , Preservação do Sêmen/métodos , Preservação do Sêmen/veterinária , Contagem de Espermatozoides , Espermatozoides/fisiologia , Ubiquitina , Ubiquitinação
7.
Zhongguo Zhen Jiu ; 38(1): 51-4, 2018 Jan 12.
Artigo em Chinês | MEDLINE | ID: mdl-29354937

RESUMO

OBJECTIVE: To explore the repair effects of acupuncture for promoting the governor vessel and tranquilizing the mind (acupuncture technique) on cerebral white matter injury of premature infants. METHODS: A total of 56 cases of cerebral whiter matter injury of premature infants, the fetal age less than 35 weeks were selected and randomized into an observation group (27 cases) and a control group (29 cases). The routine basic rehabilitation therapy was used in the two groups. Additionally, in the observation group, the acupuncture technique was added, once a day and the treatment for 15 days was as 1 course. Totally, 3 courses of treatment were required. Before and after treatment, the cranial magnetic resonance imaging (MRI) and the diffusion tensor imaging (DTI) were adopted to observe the location and severity of cerebral white matter injury. The Gesell developmental scale was used to assess the nerve motor development. RESULTS: After treatment, the difference was not significant statistically in the severity of cerebral white matter injury in the infants between the two groups (P>0.05). The FA value of cerebral white matter in the interesting zone was increased as compared with that before treatment in the infants of the two groups (both P<0.05). The result in the observation group was higher than that in the control groups (P<0.05). After treatment, DQ value of each function zone in Gesell scale was all increased as compared with that before treatment in the two groups (all P<0.05). After treatment, the DQ values of gross motor, fine motor and social adaptability in the observation group were higher than those in the control group (all P<0.05). After treatment, the difference was not significant in DQ value of individual-social and speech behaviors between the two groups (both P>0.05). CONCLUSION: Acupuncture technique for promoting the governor vessel and tranquilizing the mind promotes the repair of the function in the premature infants with cerebral white matter injury and further benefits the promotion of the intelligence.


Assuntos
Terapia por Acupuntura , Lesões Encefálicas/terapia , Recém-Nascido Prematuro , Substância Branca/lesões , Lesões Encefálicas/reabilitação , Imagem de Tensor de Difusão , Humanos , Recém-Nascido , Imageamento por Ressonância Magnética , Substância Branca/diagnóstico por imagem
8.
Tissue Cell ; 49(5): 521-527, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28720304

RESUMO

Single-cell derived bovine induced pluripotent stem cells (iPSCs) were generated by the introduction of piggyBac transposons with CAG promoting transcription factors (Oct3/4, Sox2, Klf4 and cMyc). In the study, the bovine iPSCs colony from single cell could passage more than 50 passages after enzymatic dissociation into single cells. These bovine iPSCs cells kept the normal karyotype and displayed dome shaped clones similar to mouse embryonic stem cells. They showed pluripotency in many ways, including their expression of pluripotency markers, such as OCT3/4, NANOG, SOX2, SSEA1, SSEA4, and AP in immunofluorescence assay, Oct4, Nanog, Sox2, Klf4 and cMyc in RT-PCR. Additionally, single-cell derived bovine iPSCs formed embryoid bodies and teratomas that all subsequently gave rise to differentiated cells from all three embryonic germ layers. The results showed that our reprogramming method could obtain high efficiency single-cell cloning bovine iPSCs, and the efficiency of single cell cloning is 40%.


Assuntos
Células-Tronco Pluripotentes Induzidas/citologia , Animais , Bovinos , Técnicas de Cultura de Células , Células Cultivadas , Fator 4 Semelhante a Kruppel
9.
Forensic Sci Int ; 270: 165-172, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27987400

RESUMO

Sudden unexplained death (SUD) constitutes a part of the overall sudden death that can not be underestimated. Over the last years, genetic testing on SUD has revealed that inherited channelopathies might play important roles in the pathophysiology of this disease. Ryanodine receptor type-2 (RYR2) is a kind of ion channel extensively distributed in the sarcoplasmic reticulum (SR) of myocardium. Studies on RYR2 have suggested that either dysfunction or abnormal expression of it could lead to arrhythmia, which may cause cardiac arrest. In this study, we conducted a case-control study to evaluate the association of a 4-base pair (4-bp) Indel polymorphism (rs10692285) in the 3'UTR of RYR2 with the risk of SUD and sudden cardiac death induced by coronary heart disease (SCD-AS) in a Chinese population. Logistic regression analysis showed that the insertion allele of rs10692285 had significantly increased the risk of SUD [OR=2.03; 95% confidence interval (CI)=1.08-3.77; P=0.0161; statistical power=0.743]. No relevance was observed between rs10692285 and SCD-AS. Further genotype-phenotype association analysis suggested that the expression level of RYR2 in human myocardium tissues with the insertion allele was higher than that with the deletion allele at both mRNA and protein levels. Dual-Luciferase activity assay system was used to detect the effect of rs10692285 on the transcription activity of RYR2. As expected, the result indicated that the transcription activity of RYR2 with the ins/ins genotype was higher than that with the del/del genotype. Finally, in-silico prediction revealed that different alleles of rs10692285 could alter the local structure of RYR2 mRNA and microRNA (miRNA) binding. In summary, our findings provided evidence that rs10692285 might contribute to SUD susceptibility through affecting the expression of RYR2, which suggest that abnormal ion channel activity is very likely to be the underlying mechanism of SUD, but not for SCD-AS. Thus, rs10692285 may become a potential marker for molecular diagnosis and genetic counseling of SUD.


Assuntos
Morte Súbita Cardíaca/etiologia , Mutação INDEL , Polimorfismo Genético , Canal de Liberação de Cálcio do Receptor de Rianodina/genética , Adolescente , Adulto , Idoso , Povo Asiático/genética , Estudos de Casos e Controles , China , Feminino , Predisposição Genética para Doença , Genótipo , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Miocárdio/metabolismo , Canal de Liberação de Cálcio do Receptor de Rianodina/metabolismo , Adulto Jovem
10.
Carcinogenesis ; 38(2): 168-176, 2017 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-28034876

RESUMO

Polymorphisms in pre-miRNAs may affect its expression, then have effect on its target mRNAs and be associated with cancer susceptibility. In this study, we evaluated the association of an indel polymorphism rs57408770 in pre-miR-3131 with hepatocellular carcinoma (HCC) susceptibility in a Chinese population. The contribution of rs57408770 to HCC risk was investigated in two independent case-control sets (1051 HCC and 1058 controls). Logistic regression analysis showed that the insertion allele of rs57408770 was significantly associated with an increased risk for HCC occurrence in both case-control studies. Moreover, the results of genotype-phenotype correlation analysis from both in vivo and in vitro experiments showed that the insertion allele was significantly correlated with higher expression of mature miR-3131 comparing with the deletion allele. The RNA-Binding Protein Immunoprecipitation assay results indicated that rs57408770 could affect the expression level of mature miR-3131 probably through disturbing the binding of splicing factor SRp20 with pre-miR-3131. Furthermore, overexpression of miR-3131 displayed a proliferation promoting and anti-apoptosis effect on HCC cell lines, suggesting that miR-3131 may act as a proto-oncogene in HCC. Finally, human genome-wide gene expression profile assay was used to screen the targets of miR-3131. The overexpressed miR-3131 could lead to a significant decrease of DTHD1 and XAF1 mRNA level. Taken together, our findings provided evidence that rs57408770 may play a functional role in the carcinogenesis of HCC by affecting SRp20 binding with pre-miR-3131 and affecting the expression of mature miR-3131, subsequently affecting the expression of DTHD1 and XAF1, thus confers risk for HCC.


Assuntos
Carcinoma Hepatocelular/genética , Proteínas Adaptadoras de Sinalização de Receptores de Domínio de Morte/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Neoplasias Hepáticas/genética , MicroRNAs/genética , Proteínas de Neoplasias/genética , Proteínas Adaptadoras de Transdução de Sinal , Idoso , Proteínas Reguladoras de Apoptose , Carcinoma Hepatocelular/patologia , China , Feminino , Regulação Neoplásica da Expressão Gênica , Estudos de Associação Genética , Predisposição Genética para Doença , Humanos , Mutação INDEL/genética , Neoplasias Hepáticas/patologia , Masculino , MicroRNAs/biossíntese , Pessoa de Meia-Idade , Proto-Oncogene Mas , Fatores de Risco
11.
Asian-Australas J Anim Sci ; 29(6): 793-800, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26954128

RESUMO

Most hinnies (female donkey×male horse) and mules (female horse×male donkey) are sterile with few reports of equine fertile hybrids. The main cause of this sterility is thought to be a meiotic block to spermatogenesis and oogenesis. This study compared the developmental features of the testes and a histological analyses of spermatogenesis in a male hinny with those of a normal, fertile stallion and Jack donkey. Hinny testes showed a thicker tunica albuginea, fewer blood vessels and more connective tissue in the testis parenchyma than those of the stallion and Jack donkey. Although the mean number of seminiferous tubules was significantly higher in stallion and hinny than Jack donkey (p<0.01), the mean proportion of seminiferous tubules was lower in the hinny (p<0.01) which resulted in a smaller diameter of seminiferous tubules. The mean number of spermatogonia and spermatocytes per unit area were significantly lower in hinny testis (p<0.01) and no spermatids or mature spermatozoa cells were found during immunofluorescent analyses. These results indicated that defects in seminiferous tubule development and structure occur in the testis of hinnies. Furthermore, most spermatogonia and spermatocytes cease development in synapsis during mid-meiosis of spermatocytes, which results in a block to spermatogenesis that prevents the formation of spermatids and matured spermatozoa during meiosis in male hinnies.

12.
Carcinogenesis ; 36(10): 1136-43, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26163879

RESUMO

The growth arrest special 5 (GAS5) is known to be involved in various cancers. However, its expression regulation remains unclear. Polymorphisms in the promoter region of GAS5 may affect its expression and be associated with cancer susceptibility. In this research, we first evaluated the association of a 5-base pair indel polymorphism (rs145204276) in the promoter region of GAS5 with hepatocelluar carcinoma (HCC) susceptibility in Chinese populations. Logistic regression analysis showed that the deletion allele of rs145204276 significantly increased the risk of HCC in two independent case control sets (1034 HCC and 1054 controls). Further genotype-phenotype association analysis revealed that the deletion allele was markedly correlated with higher expression of GAS5 in HCC tissues. The luciferase activity analysis in an in vitro reporter gene system suggested that the deletion allele improved an increased expression of GAS5 in three hepatoma cell lines. Intriguingly, overexpression of GAS5 displayed an anti-apoptosis effect in HCC cell lines, GAS5 knockdown could partially revert this anti-apoptosis effect, suggesting that GAS5 may act as a proto-oncogene in HCC, in contrast with its inhibitory role in other cancers. Further pyrosequencing revealed that the genotypes of rs145204276 were associated with methylation status of GAS5 promoter region. Taken together, our findings provided evidence that rs145204276 may contribute to hepatocarcinogenesis by affecting methylation status of the GAS5 promoter and subsequently its transcriptional activity thus serving as a potential therapy target for HCC.


Assuntos
Carcinoma Hepatocelular/genética , Mutação INDEL , Neoplasias Hepáticas/genética , RNA Longo não Codificante/genética , Adulto , Alelos , Carcinoma Hepatocelular/patologia , Feminino , Regulação Neoplásica da Expressão Gênica , Estudos de Associação Genética , Predisposição Genética para Doença , Humanos , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Regiões Promotoras Genéticas , Proto-Oncogene Mas
13.
Trials ; 16: 212, 2015 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-25963295

RESUMO

BACKGROUND: Many patients experience nausea and vomiting during chemotherapy treatment. Evidence demonstrates that electroacupuncture is beneficial for controlling chemotherapy-induced nausea and vomiting (CINV). However, the acupoint or matching acupoint with the best efficacy for controlling CINV still remains unidentified. METHODS/DESIGN: This study consists of a randomized controlled trial (RCT) with four parallel arms: a control group and three electroacupuncture groups (one with Neiguan (PC6), one with Zhongwan (CV12), and one with both PC6 and CV12). The control group received standard antiemetic only, while the other three groups received electroacupuncture stimulation with different acupoints besides the standard antiemetic. The intervention is done once daily from the first day (day 1) to the fourth day (day 4) during chemotherapy treatment. The primary outcome measures include frequency of nausea, vomiting and retching. The secondary outcome measures are the grade of constipation and diarrhea, electrogastrogram, assessment of quality of life, assessment of anxiety and depression, and other adverse effects during the chemotherapy. Assessments are scheduled from one day pre-chemotherapy (day 0) to the fifth day of chemotherapy (day 5). Follow-ups are done from day 6 to day 21. DISCUSSION: The aim of this study is to evaluate the efficacy and safety of electro-acupuncture with different acupoints in the management of CINV. TRIAL REGISTRATION: The register number of randomized controlled trial is NCT02195908 . The date of registration was 21 July 2014.


Assuntos
Pontos de Acupuntura , Antineoplásicos/efeitos adversos , Eletroacupuntura/métodos , Náusea/prevenção & controle , Vômito/prevenção & controle , Antieméticos/uso terapêutico , Protocolos Clínicos , Terapia Combinada , Eletroacupuntura/efeitos adversos , Humanos , Náusea/induzido quimicamente , Náusea/fisiopatologia , Náusea/psicologia , Qualidade de Vida , Projetos de Pesquisa , Fatores de Tempo , Resultado do Tratamento , Vômito/induzido quimicamente , Vômito/fisiopatologia , Vômito/psicologia
14.
Tumour Biol ; 36(7): 5467-72, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25687183

RESUMO

It has been reported that miR-21 is upregulated in hepatocellular carcinoma (HCC), and overexpressed miR-21 plays a key role in promoting cell cycle progression, reducing cell death and favoring angiogenesis and invasion. Overexpression of hepatocellular carcinoma, downregulated 1 (HEPN1) exhibits an antiproliferative effect on HepG2 cells, suggesting that silencing of HEPN1 may contribute to carcinogenesis of hepatocytes. In silico analysis revealed that HEPN1 may be a potential target of miR-21. Using quantitative reverse transcription PCR and Western blot, we found that HEPN1 was strikingly downregulated in both mRNA (fold change was 33.5, P < 0.0001) and protein levels in human HCC tumor tissues, in comparison with the adjacent non-tumor tissues. More importantly, the expression level of HEPN1 was inversely correlated with the expression of miR-21 in HCC (R (2) = 0.442, P < 0.0001). The combination between the 3' untranslated region (UTR) of HEPN1 with miR-21 was experimentally verified by a miRNA luciferase reporter approach. The suppressed cell proliferation upon stimulation of miR-21 inhibitor could be partially abolished by knocking down HEPN1, so inhibition of miR-21 expression in HCC cells profoundly suppressed cell proliferation partially by upregulating HEPN1 expression. Taken together, the current study suggested an underlying mechanism that miR-21 directly target HEPN1 and inhibit its expression during the carcinogenesis of HCC. HEPN1 may thus be a candidate as a therapeutic target for patients with HCC.


Assuntos
Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , MicroRNAs/genética , Proteínas/metabolismo , Apoptose/genética , Carcinoma Hepatocelular/patologia , Ciclo Celular/genética , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , Células Hep G2 , Humanos , Neoplasias Hepáticas/patologia , MicroRNAs/metabolismo , Proteínas/genética , RNA Mensageiro/biossíntese
15.
PLoS One ; 9(9): e106841, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25198338

RESUMO

BACKGROUND: PTPN11, which encodes tyrosine phosphatase Shp2, is a critical gene mediating cellular responses to hormones and cytokines. Loss of Shp2 promotes hepatocellular carcinoma (HCC), suggesting that PTPN11 functions as a tumor suppressor in HCC tumorgenesis. The aim of this study was to evaluate the effects of the short tandem repeat (STR) polymorphism (rs199618935) within 3'UTR of PTPN11 on HCC susceptibility in Chinese populations. METHODOLOGY/PRINCIPAL FINDINGS: We analyzed the associations in 400 patients from Jiangsu province of China, validating the findings in an additional 305 patients from Shanghai of China. Unconditional logistic regression was used to analyze the association between rs199618935 and HCC risk. Additional biochemical investigations and in-silico studies were used to evaluate the possible functional significance of this polymorphism. Logistic regression analysis showed that compared with individuals carrying shorter alleles (11 and 12 repeats), those subjects who carry longer alleles (13 and 14 repeats) had a significantly decreased risk of HCC [adjusted odds ratio (OR) = 0.63, 95% confidence interval (CI)  = 0.53-0.76, P = 2.00 × 10(-7)], with the risk decreased even further in those carrying allele 15 and 16 (adjusted OR = 0.46, 95% CI = 0.34-0.62, P = 1.00 × 10(-7)). Biochemical investigations showed that longer alleles of rs199618935 conferred higher PTPN11 expression in vivo and in vitro. The altered luciferase activities in reporter gene system suggested that STR regulation of PTPN11 expression could be a transcriptional event. Finally, in-silico prediction revealed that different alleles of rs199618935 could alter the local structure of PTPN11 mRNA. CONCLUSIONS/SIGNIFICANCE: Taken together, our findings suggested that the STR polymorphism within PTPN11 contributes to hepatocarcinogenesis, possibly by affecting PTPN11 expression through a structure-dependent mechanism. The replication of our studies and further functional studies are needed to validate our findings.


Assuntos
Carcinoma Hepatocelular/genética , Predisposição Genética para Doença , Neoplasias Hepáticas/genética , Repetições de Microssatélites , Polimorfismo Genético , Proteína Tirosina Fosfatase não Receptora Tipo 11/genética , Sequência de Bases , Estudos de Casos e Controles , China , Primers do DNA , Humanos , Reação em Cadeia da Polimerase em Tempo Real
16.
Stem Cells Int ; 2014: 409021, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25610470

RESUMO

Blastocyst injection and morula aggregation are commonly used to evaluate stem cell pluripotency based on chimeric contribution of the stem cells. To assess the protocols for generating chimeras from stem cells, 8-cell mouse embryos were either injected or cocultured with mouse embryonic stem cells and induced pluripotent stem cells, respectively. Although a significantly higher chimera rate resulted from blastocyst injection, the highest germline contribution resulted from injection of 8-cell embryos with embryonic stem cells. The fully agouti colored chimeras were generated from both injection and coculture of 8-cell embryos with embryonic stem cells. Additionally, microsatellite DNA screening showed that the fully agouti colored chimeras were fully embryonic stem cell derived mice. Unlike embryonic stem cells, the mouse chimeras were only generated from injection of 8-cell embryos with induced pluripotent stem cells and none of these showed germline transmission. The results indicated that injection of 8-cell embryos is the most efficient method for assessing stem cell pluripotency and generating induced pluripotent stem cell chimeras, embryonic stem cell chimeras with germline transmission, and fully mouse embryonic stem cell derived mice.

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