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1.
iScience ; 21: 375-390, 2019 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-31704649

RESUMO

Epigenomic changes and stem cell deterioration are two hallmarks of aging. Accumulating evidence suggest that senescence of mesenchymal stromal cells (MSCs) perpetuates aging or age-related diseases. Here we report that two H3K9 demethylases, KDM3A and KDM4C, regulate heterochromatin reorganization via transcriptionally activating condensin components NCAPD2 and NCAPG2 during MSC senescence. Suppression of KDM3A or KDM4C by either genetic or biochemical approach leads to robust DNA damage response and aggravates cellular senescence, whereas overexpression of KDM3A/KDM4C or NCAPD2 promotes heterochromatin reorganization and blunts DNA damage response. Moreover, MSCs derived from Kdm3a-/- mice exhibit defective chromosome organization and exacerbated DNA damage response, which are associated with accelerated bone aging. Consistently, analysis of human bone marrow MSCs and transcriptome database reveals inverse correlation of KDM3A/KDM4C and/or NCAPD2/NCAPG2 with aging. Taken together, the present finding unveils that H3K9 demethylases function as a surveillance mechanism to restrain DNA damage accumulation in stem cells during aging.

2.
Stem Cells Dev ; 28(20): 1365-1375, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31580778

RESUMO

Glaucoma is characterized by retinal ganglion cell (RGC) degeneration and is the second leading cause of blindness worldwide. However, current treatments such as eye drop or surgery have limitations and do not target the loss of RGC. Regenerative therapy using embryonic stem cells (ESCs) holds a promising option, but ethical concern hinders clinical applications on human subjects. In this study, we employed spermatogonial stem cells (SSCs) as an alternative source of ESCs for cell-based regenerative therapy in mouse glaucoma model. We generated functional RGCs from SSCs with a two-step protocol without applying viral transfection or chemical induction. SSCs were first dedifferentiated to embryonic stem-like cells (SSC-ESCs) that resemble ESCs in morphology, gene expression signatures, and stem cell properties. The SSC-ESCs then differentiated toward retinal lineages. We showed SSC-ESC-derived retinal cells expressed RGC-specific marker Brn3b and functioned as bona fide RGCs. To allow in vivo RGC tracing, Brn3b-EGFP reporter SSC-ESCs were generated and the derived RGCs were subsequently transplanted into the retina of glaucoma mouse models by intravitreal injection. We demonstrated that the transplanted RGCs could survive in host retina for at least 10 days after transplantation. SSC-ESC-derived RGCs can thus potentially be a novel alternative to replace the damaged RGCs in glaucomatous retina.

3.
J Exp Med ; 2019 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-31658987

RESUMO

Asthenozoospermia is a common cause of male infertility, but its etiology remains incompletely understood. We recruited three Pakistani infertile brothers, born to first-cousin parents, displaying idiopathic asthenozoospermia but no ciliary-related symptoms. Whole-exome sequencing identified a missense variant (c.G5408A, p.C1803Y) in DNAH17, a functionally uncharacterized gene, recessively cosegregating with asthenozoospermia in the family. DNAH17, specifically expressed in testes, was localized to sperm flagella, and the mutation did not alter its localization. However, spermatozoa of all three patients showed higher frequencies of microtubule doublet(s) 4-7 missing at principal piece and end piece than in controls. Mice carrying a homozygous mutation (Dnah17M/M ) equivalent to that in patients recapitulated the defects in patients' sperm tails. Further examinations revealed that the doublets 4-7 were destabilized largely due to the storage of sperm in epididymis. Altogether, we first report that a homozygous DNAH17 missense variant specifically induces doublets 4-7 destabilization and consequently causes asthenozoospermia, providing a novel marker for genetic counseling and diagnosis of male infertility.

4.
Med Sci Monit ; 25: 7258-7271, 2019 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-31560680

RESUMO

BACKGROUND Colorectal cancer (CRC) has become a heavy health burden around the world, accounting for about 10% of newly diagnosed cancer cases. In the present study, we aimed to establish the miRNA-based prediction signature to assess the prognosis of CRC patients. MATERIAL AND METHODS A total of 451 CRC patients' expression profiles and clinical information were download from the TCGA database. LASSO Cox regression was conducted to construct the overall survival (OS)- and recurrence-free survival (RFS)-associated prediction signatures, by which CRC patients were divided into low- and high-risk groups. Kaplan-Meier (K-M) curve and receiver operating characteristic (ROC) curves were used to explore the discriminatory ability and stability of the signatures. Functional enrichment analyses were performed to identify the probable mechanisms. RESULTS miRNA-216a, miRNA-887, miRNA-376b, and miRNA-891a were used to build the prediction formula associated with OS, while miR-1343, miR-149, miR-181a-1, miR-217, miR-3130-1, miR-378a, miR-542, miR-6716, miR-7-3, miR-7702, miR-677, and miR-891a were obtained to construct the formula related to RFS. K-M curve and ROC curve revealed the good discrimination and efficiency of OS in the training (P<0.001, AUC=0.712) and validation cohorts (P=0.019, AUC=0.657), as well as the results of RFS in the training (P<0.001, AUC=0.714) and validation cohorts (P=0.042, AUC=0.651). The function annotations for the targeted genes of these miRNAs show the potential mechanisms of CRC. CONCLUSIONS We established 2 novel miRNA-based prediction signatures of OS and RFS, which are reliable tools to assess the prognosis of CRC patients.

5.
Chem Res Toxicol ; 32(10): 2135-2143, 2019 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-31512855

RESUMO

Topoisomerase II is a nuclear enzyme involved in the maintenance of DNA and is an effective anticancer drug target. However, several clinical topoisomerase II-targeted agents display significant off-target toxicities and adverse events. Thus, it is important to continue characterizing compounds with activity against topoisomerase II. We previously analyzed α-(N)-heterocyclic thiosemicarbazone copper(II) complexes against human topoisomerase IIα (TOP2A), but humans also express topoisomerase IIß (TOP2B), which has distinct functional roles. Therefore, we examined two α-(N)-heterocyclic thiosemicarbazone copper [Cu(II)] complexes for activity against TOP2B in a purified system. The Cu(II) complexes, Cu(APY-ETSC)Cl and Cu(BZP-ETSC)Cl, were examined using plasmid DNA cleavage, supercoiled DNA relaxation, enzyme inactivation, protein cross-linking, DNA ligation, and ATP hydrolysis assays with TOP2B to determine whether these compounds act similarly against both enzymes. Both of the Cu(II) thiosemicarbazone (Cu-TSC) complexes we tested disrupted the function of TOP2B in a way similar to the effect on TOP2A. In particular, TOP2B DNA cleavage activity is increased in the presence of these compounds, while the relaxation and ATPase activities are inhibited. Further, both Cu-TSCs stabilize the N-terminal DNA clamp of TOP2A and TOP2B and rapidly inactivate TOP2B when the compounds are present before DNA. Our data provide evidence that the Cu-TSC complexes we tested utilize a similar mechanism against both isoforms of the enzyme. This mechanism may involve interaction with the ATPase domain of TOP2A and TOP2B outside of the ATP binding pocket. Additionally, these data support a model of TOP2 function where the ATPase domain communicates with the DNA cleavage/ligation domain.

6.
Theranostics ; 9(17): 5049-5064, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31410201

RESUMO

Rationale: Abnormal Wnt/ß-catenin signaling in the endometrium can lead to both embryo implantation failure and severe pathogenic changes of the endometrium such as endometrial cancer and endometriosis. However, how Wnt/ß-catenin signaling is regulated in the endometrium remains elusive. We explored possible regulation of Wnt/ß-catenin signaling by multi-drug resistance protein 4 (MRP4), a potential target in cancer chemotherapy, and investigated the mechanism. Methods: Knockdown of MRP4 was performed in human endometrial cells in vitro or in a mouse embryo-implantation model in vivo. Immunoprecipitation, immunoblotting and immunofluorescence were used to assess protein interaction and stability. Wnt/ß-catenin signaling was assessed by TOPflash reporter assay and quantitative PCR array. Normal and endometriotic human endometrial tissues were examined. Data from human microarray or RNAseq databases of more than 100 participants with endometriosis, endometrial cancer or IVF were analyzed. In vitro and in vivo tumorigenesis was performed. Results: MRP4-knockdown, but not its transporter-function-inhibition, accelerates ß-catenin degradation in human endometrial cells. MRP4 and ß-catenin are co-localized and co-immunoprecipitated in mouse and human endometrium. MRP4-knockdown in mouse uterus reduces ß-catenin levels, downregulates a series of Wnt/ß-catenin target genes and impairs embryo implantation, which are all reversed by blocking ß-catenin degradation. Analysis of human endometrial biopsy samples and available databases reveals significant and positive correlations of MRP4 with ß-catenin and Wnt/ß-catenin target genes in the receptive endometrium in IVF, ectopic endometriotic lesions and endometrial cancers. Knockdown of MRP4 also inhibits in vitro and in vivo endometrial tumorigenesis. Conclusion: A previously undefined role of MRP4 in stabilizing ß-catenin to sustain Wnt/ß-catenin signaling in endometrial cells is revealed for both embryo implantation and endometrial disorders, suggesting MRP4 as a theranostic target for endometrial diseases associated with Wnt/ß-catenin signaling abnormality.

7.
Anal Chem ; 91(17): 11455-11460, 2019 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-31397151

RESUMO

A hydrothermal strategy for preparing boron and nitrogen codoped carbon quantum dots was studied using the precursors of p-amino salicylic acid, boric acid and ethylene glycol dimethacrylate. The boron and nitrogen codoped carbon quantum dots have high fluorescence intensity, good monodispersity, high stability, superior water solubility, and a fluorescence quantum yield of 19.6%. Their average size is 5 nm. Their maximum excitation and emission wavelengths are 380 and 520 nm, respectively. Permanganate (MnO4-) quenched boron and nitrogen codoped carbon quantum dots fluorescence through inner filter effect and static quenching effects. The linear relation between quenching efficiency and MnO4- concentration ranged from 0.05 to 60 µmol/L with a detection limit of 13 nmol/L. In the presence of captopril, MnO4- was reduced to Mn2+ and the fluorescence of boron and nitrogen codoped carbon quantum dots was recovered. The linear range between recovery and captopril concentration was from 0.1 to 60 µmol/L. The limit of detection was 0.03 µmol/L. The developed method can be employed as a sensitive fluorescence sensing platform for MnO4-. It has been successfully used for captopril detection in mouse plasma.

8.
Gene ; 711: 143925, 2019 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-31212048

RESUMO

More than 2300 genes have been reported to be involved in spermatogenesis but the functional roles of most genes in male fertility remain to be elucidated. In this study, we explored the function of dipeptidase 3 (Dpep3), a gene predicted to be testis-specific, in male fertility of mice. We showed that Dpep3 is evolutionarily conserved in human and mouse along with other eutherians. Its mRNA was exclusively detected in testicular tissue and expressed in testes from 7 days postpartum. To further explore its role in male fertility, we generated Dpep3 knockout mice (Dpep3-/-) using the CRISPR/Cas9 technology and found that the male Dpep3-/- mice are fertile despite a significant reduction in sperm count. Histology of testis and progression of meiotic prophase I showed no obvious difference between wild-type and Dpep3-/- mice. All these findings indicate that Dpep3 is not essential for male fertility in mice. These findings will help other researchers to avoid research duplication, save their time and resources to focus on the genes that are indispensable for male fertility.


Assuntos
Dipeptidases/genética , Dipeptidases/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Espermatogênese , Testículo/metabolismo , Animais , Sequência Conservada , Técnicas de Inativação de Genes , Humanos , Infertilidade Masculina/genética , Infertilidade Masculina/metabolismo , Masculino , Camundongos , Especificidade de Órgãos , Filogenia , Contagem de Espermatozoides , Motilidade Espermática
9.
Redox Biol ; 24: 101221, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31153039

RESUMO

To test our hypothesis that proatherogenic lysophosphatidylcholine (LPC) upregulates trained immunity pathways (TIPs) in human aortic endothelial cells (HAECs), we conducted an intensive analyses on our RNA-Seq data and histone 3 lysine 14 acetylation (H3K14ac)-CHIP-Seq data, both performed on HAEC treated with LPC. Our analysis revealed that: 1) LPC induces upregulation of three TIPs including glycolysis enzymes (GE), mevalonate enzymes (ME), and acetyl-CoA generating enzymes (ACE); 2) LPC induces upregulation of 29% of 31 histone acetyltransferases, three of which acetylate H3K14; 3) LPC induces H3K14 acetylation (H3K14ac) in the genomic DNA that encodes LPC-induced TIP genes (79%) in comparison to that of in LPC-induced effector genes (43%) including ICAM-1; 4) TIP pathways are significantly different from that of EC activation effectors including adhesion molecule ICAM-1; 5) reactive oxygen species generating enzyme NOX2 deficiency decreases, but antioxidant transcription factor Nrf2 deficiency increases, the expressions of a few TIP genes and EC activation effector genes; and 6) LPC induced TIP genes(81%) favor inter-chromosomal long-range interactions (CLRI, trans-chromatin interaction) while LPC induced effector genes (65%) favor intra-chromosomal CLRIs (cis-chromatin interaction). Our findings demonstrated that proatherogenic lipids upregulate TIPs in HAECs, which are a new category of qualification markers for chronic disease risk factors and conditional DAMPs and potential mechanisms for acute inflammation transition to chronic ones. These novel insights may lead to identifications of new cardiovascular risk factors in upregulating TIPs in cardiovascular cells and novel therapeutic targets for the treatment of metabolic cardiovascular diseases, inflammation, and cancers. (total words: 245).

10.
J Clin Invest ; 130: 3754-3769, 2019 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-31211699

RESUMO

Although joint pain in rheumatoid arthritis (RA) is conventionally thought to result from inflammation, arthritis pain and joint inflammation are at least partially uncoupled. This suggests that additional pain mechanisms in RA remain to be explored. Here we show that FcγRI, an immune receptor for IgG immune complex (IgG-IC), is expressed in a subpopulation of joint sensory neurons and that, under naïve conditions, FcγRI crosslinking by IgG-IC directly activates the somata and peripheral terminals of these neurons to evoke acute joint hypernociception without obvious concurrent joint inflammation. These effects were diminished in both global and sensory neuron-specific Fcgr1 knockout mice. In murine models of inflammatory arthritis, FcγRI signaling was upregulated in joint sensory neurons. Acute blockade or global genetic deletion of Fcgr1 significantly attenuated arthritis pain and hyperactivity of joint sensory neurons without measurably altering joint inflammation. Conditional deletion of Fcgr1 in sensory neurons produced similar analgesic effects in these models. We therefore suggest that FcγRI expressed in sensory neurons contributes to arthritis pain independently of its functions in inflammatory cells. These findings expand our understanding of the immunosensory capabilities of sensory neurons and imply that neuronal FcγRI merits consideration as a target for treating RA pain.

11.
FASEB J ; 33(8): 9075-9086, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31084574

RESUMO

As the major somatic cell type, Sertoli cells undergo active proliferation and play essential roles to establish testis cord at fetal stage. They also function to maintain germ cell development throughout the life of testicular development. However, the significance of Sertoli cell number for testis cord development and gonocyte fate is still unclear. Nuclear protein ataxia-telangiectasia (NPAT, also known as p220), a substrate of cyclin E/cyclin-dependent kinase 2, is well known as a regulator of cell proliferation through regulating histone expression. To study the role of NPAT during Sertoli cell development, we generated a mouse strain carrying conditional floxed Npat alleles, when crossing with anti-Müllerian hormone-cre, leading to the specific deletion of Npat in Sertoli cells. Npat disruption in Sertoli cells inhibited the programmed proliferation of fetal Sertoli cells resulting in disruption of developing testis cords, and subsequent postnatal mutant testes were severely hypoplastic. Germ cells, which are presumed to be in quiescent status during perinatal stage, exited G0 phase arrest and re-enter mitotic cell cycle prematurely. Of particular note, some germ cells possessed the meiotic signal in Npat-deficient testes. Our data thus indicates that the function of Npat-dependent Sertoli cells is essential at multiple steps in testis development, and this study also identifies Sertoli cells as a major regulator of germ cell development, which are required to maintain a local growth niche to repress premature mitosis and meiosis of gonocytes.-Jiang, X., Yin, S., Fan, S., Bao, J., Jiao, Y., Ali, A., Iqbal, F., Xu, J., Zhang, Y., Shi, Q. Npat-dependent programmed Sertoli cell proliferation is indispensable for testis cord development and germ cell mitotic arrest.

12.
Am J Emerg Med ; 37(8): 1571-1576, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31085013

RESUMO

BACKGROUND: Sepsis is the leading cause of morbidity and mortality in newborns. CD64 combined with c-reactive protein (CRP) could improve the sensitivity and specificity of neonatal sepsis diagnosis, but the results were still controversial. Therefore, this meta-analysis was conducted to clarify the importance of CD64 combined with CRP in the diagnosis of neonatal sepsis. METHODS: The researches published as of December 24, 2018 were comprehensively searched in PubMed, Embase (included Embase and Medline), the Cochrane Library and Web of Science. Totally, 8 articles were included, involving 1114 objects. Statistical calculations were performed using Stata14.0 and Review Manager 5.3. RESULTS: The diagnostic accuracy of all included studies was pooled as follows: sensitivity, 0.95 (95% CI: 0.86-0.98); specificity, 0.86 (95% CI: 0.74-0.93); positive likelihood ratio (PLR), 6.8 (95% CI: 3.50-13.20); negative likelihood ratio (NLR), 0.06 (95% CI: 0.02-0.18); diagnostic odds ratio (DOR), 118.0 (95% CI: 25.00-549.00), and the area under the curve (AUC) was 0.96 (95% CI: 0.94-0.97). It was found that heterogeneity was not caused by threshold effect (P = 0.16), but the results of sensitivity (I2 = 87.57%) and specificity (I2 = 89.07%) analyses indicated significant heterogeneity between studies. CONCLUSIONS: The combined application of CD64 and CRP improved the accuracy of neonatal sepsis diagnosis.

13.
Mol Oncol ; 13(9): 1855-1873, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31116512

RESUMO

DDR1 has been identified as a cancer-associated receptor tyrosine kinase that is highly expressed in several malignancies relative to normal tissues. Clinically approved multi-kinase inhibitors, such as nilotinib, inhibit DDR1-mediated tumor growth in xenograft models, suggesting DDR1 might be a potential target for cancer treatments. Here, we employed an antibody-based strategy with a novel anti-DDR1 antibody-drug conjugate (ADC) for colon carcinoma treatment. We developed T4 H11 -DM4, an ADC targeting DDR1 which carries the tubulin inhibitor payload DM4. Immunohistochemical analysis of a tissue microarray containing 100 colon cancer specimens revealed that DDR1 was highly expressed in 81% of tumor tissues. Meanwhile, high expression of DDR1 was associated with poor survival in patients. In vitro, T4 H11 -DM4 exhibited potent anti-proliferative activity with half maximal inhibitory concentration (IC50 ) values in the nanomolar range in a panel of colon cancer cell lines. In vivo, the antitumor efficacy of T4 H11 -DM4 was evaluated in three colon cancer cell lines expressing different levels of DDR1. T4 H11 -DM4 achieved complete tumor regression at doses of 5 and 10 mg·kg-1 in HT-29 and HCT116 tumor models. Moreover, a correlation between in vivo efficacy of T4 H11 -DM4 and the levels of DDR1 expression on the cell surface was observed. Tumor cell proliferation was caused by the induction of mitotic arrest, indicating that the antitumor effect in vivo was mediated by DM4. In addition, T4 H11 -DM4 was efficacious in oxaliplatin-resistant colon cancer models. In exploratory safety studies, T4 H11 -DM4 exhibited no overt toxicities when multi-doses were administered at 10 mg·kg-1 into BALB/c nude mice or when a single dose up to 50 mg·kg-1 was administered into BALB/c mice. Overall, our findings highlight the potential of DDR1-targeted ADC and may facilitate the development of a new effective therapeutic strategy for colon cancer.

14.
J Chromatogr A ; 1599: 180-186, 2019 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-30961965

RESUMO

Jian-Gu Injection (JGI, Premna fulva Craib) has been demonstrated to be effective in the clinical treatment of bone hyperplasia. However, an effective purification method of the JGI flavone C-glycosides as reference materials is not available. The present work developed a recycling counter-current chromatography approach to prepare these materials in high quality. An optimized biphasic solvent system composed of ethyl acetate/n-butanol/water (1:9:10, v/v/v) was employed to purify the five congeneric flavone C-glycosides, identified as apigenin 6,8-di-C-ß-d-glucopyranoside (vicenin 2), apigenin 6-C-ß-d-xylopyranosyl-8-C-ß-d-glucopyranoside (vicenin 1), apigenin 6-C-ß-d-xylopyranosyl-8-C-ß-d-galactopyranoside, apigenin 6-C-ß-d-glucopyranosyl-8-C-ß-d-xylopyranoside (vicenin 3), and apigenin 6-C-ß-d-galactopyranosyl-8-C-ß-d-xylopyranoside, by means of UHPLC-PDA-ESI-IT-ToF-MSn and NMR spectroscopy.


Assuntos
Distribuição Contracorrente , Glicosídeos/isolamento & purificação , Medicina Tradicional Chinesa , Extratos Vegetais/isolamento & purificação , Apigenina/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Flavonas/isolamento & purificação , Glucosídeos/isolamento & purificação , Glicosídeos/química , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Extratos Vegetais/química , Solventes/química
15.
Horm Res Paediatr ; 91(1): 9-16, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30947225

RESUMO

BACKGROUND: Congenital hypogonadotropic hypogonadism (CHH) is a heterogeneous disorder characterized by delayed or loss of puberty and infertility due to functional deficiency in the hypothalamic gonadotropin-releasing hormone (GnRH). CHH can be classified into 2 subtypes on the basis of olfaction: Kallmann syndrome and normosmic CHH (nCHH). The spectrum of genetic variants causing CHH is continually expanding. Here, we recruited a consanguineous Pakistani family having 2 male and 2 female infertile patients diagnosed with idiopathic nCHH. AIMS: The aim of this study was to investigate the genetic cause of nCHH in the family. METHODS: Clinical and physical analyses were performed for the patients. Genetic analysis was carried out using whole exome and Sanger sequencing. RESULTS: Clinical and physical investigations confirmed low levels of gonadotropins and failure of secondary sexual development in the patients. Genetic analysis identified a novel nonsense mutation (chr4: g.68619942G>A, c.112C>T, p.Arg38*) in the gonadotropin-releasing hormone receptor gene (GNRHR) recessively co-segregating with nCHH in this family. All the patients are homozygous and their parents are heterozygous carriers, while normal siblings are heterozygous carriers or wild-type for this mutation, indicating that the identified mutation is pathogenic for nCHH in the family. CONCLUSION: We report the first homozygous nonsense mutation in the GNRHR gene (chr4: g. 68619942G>A, c.112C>T, p. Arg38*) that is associated with familial nCHH. Hence, our study displayed a good correlation of the genotype and phenotype of nCHH patients.

16.
Sci China Life Sci ; 62(4): 544-552, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30919279

RESUMO

The balanced actions between ubiquitination and deubiquitination precisely control the levels of various proteins vital for spermatogenesis. Ubiquitin-specific processing proteases (USPs) are the largest family of deubiquitinatingenzymes(DUBs), containing more than 50 members. So far, the functions of only a few USPs in male fertility have been studied, the roles of the majority are yet unknown. The present study aimed to explore the function of Usp29 (ubiquitin-specific protease 29) in male fertility. We found that Usp29 showed predominant expression in mouse testis, and its mRNA expression started to increase at 14 days postpartum (dpp), with a peak at 28 and 35 dpp. Using CRISPR/Cas9 technology, we generated Usp29 knockout mice (Usp29-/-). Usp29-/- mice exhibited no overt developmental anomalies. Further examination revealed that Usp29-/- mice had normal fertility and showed no detectable difference in the testis/body weight ratio, testicular and epididymal histology as well as epididymal sperm count from the wild-type littermates. Moreover, Usp29 is not a pseudogene in mice. Taken together, our study first reported that though Usp29 is predominantly expressed in the testis, it is not essential for male fertility in mice.

17.
Biochem Biophys Res Commun ; 511(2): 381-386, 2019 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-30803758

RESUMO

Microtubules (MTs) is one of the most important proteins in eukaryotic cells and plays a key role in the maintenance of cell morphology and cell division. The discovery and development of small molecule drugs targeting MTs has always been an important direction of anti-cancer research. Nowadays 4-Aryl-4H-chromenes have emerged as potent microtubule-targeting agents (MTAs) for various cancers. Crolibulin, a derivative of 4-Aryl-4H-chromenes, which has been progressed to Phase I/II clinical testing's for anaplastic thyroid cancer with the National Cancer Institute. However, the design and development of 4-Aryl-4H-chromenes family drugs have been hindered for a long time by the lack of structural information of the tubulin-agent complex. Here we report a 2.5 Šcrystal structure of tubulin complexed with crolibulin. This complex structure reveals the interactions between crolibulin and tubulin, helps explain the results of the structure-activity-relationship (SAR) studies and provides a solid structural basis for the design and development of new 4-Aryl-4H-chromenes derivatives as MTAs.

18.
ACS Sens ; 4(2): 504-512, 2019 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-30693767

RESUMO

A sensitive sandwich electrochemiluminescence immunosensor was established by employing graphene oxide-PEI-carbon quantum dots (CQDs)-Au nanohybrid as probe to measure carbohydrate antigen 15-3 (CA15-3), a breast cancer biomarker. In this work, nanocomposites of Ag nanoparticles and polydopamine (AgNPs-PDA) were synthesized by redox reaction between dopamine and Ag+. The nanocomposite with high surface area can provide an efficient substrate for immobilizing initial antibody (Ab1). Carbon quantum dots (CQDs) are fixed on polyethylenimine-functionalized graphene oxide (PEI-GO) by amide bonds. Au nanoparticles are modified on CQDs-decorated PEI-GO substrates. The secondary antibody (Ab2) was immobilized by AuNPs/CQDs-PEI-GO composite. CQDs can be assembled onto the surface of an electrode by incorporation of CA15-3 with Ab1 and Ab2. Under the synergistic action of AgNPs, polydopamine, AuNPs, and PEI-GO, the ECL signal of CQDs is greatly amplified as an excellent conductive material to facilitate electron transfer rate and further increase electrochemical detection capability. Under optimal conditions, the fabricated immunosensor showed a linear concentration range from 0.005 to 500 U mL-1, with a detection limit of 0.0017 U mL-1 (signal-to-noise ratio of 3) for CA15-3. The designed ECL immunosensor displayed receivable accuracy, excellent stability, and high specificity. The results of the detection of human serum samples are satisfactory, revealing that the method offers a potential application for the clinical diagnosis of tumor markers.

19.
Chemosphere ; 222: 71-82, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30690403

RESUMO

Permanganate is a versatile chemical oxidant, and has undergone a dramatic evolution toward deep insight into its reaction mechanism. However, the hydrogen abstraction of the NH bond by permanganate remains unclear. We studied the permanganate oxidation of the emerging micropollutant sulfamethoxazole in acidic aqueous solution. The reaction followed autocatalytic kinetics and demonstrated first-order with respect to each reactant. The presence of HMnO4 accelerated the reaction rate, which was four orders of magnitude higher than that of MnO4-. Based on the identified products, the rate-limiting step was determined to be simple NH bond oxidation by metal-oxo species permanganate. The mechanism was then studied computationally by density functional theory (DFT) using ammonia as the simplest model. Results showed that the NH bond oxidation by MnO4- (32.86 kcal/mol) was a concerted mechanism similar to that of CH bond oxidation, whereas HMnO4 oxidation of the NH bond (10.44 kcal/mol) was a stepwise electron-proton transfer. This reminds us that coordination of Brønsted acid could not only produce the stronger electrophile but also change the reaction mode by avoiding the bond cleavage in electron transfer process.


Assuntos
Transporte de Elétrons , Compostos de Manganês/química , Óxidos/química , Prótons , Sulfametoxazol , Teoria da Densidade Funcional , Hidrogênio , Cinética , Oxirredução , Sulfametoxazol/química
20.
BMC Med Inform Decis Mak ; 18(1): 129, 2018 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-30514290

RESUMO

BACKGROUND: Colorectal cancer incidence and mortality have been increasing in China and as one of the most important health problems facing the nation. Adequate dissemination of correct information about colorectal cancer could help in reducing cancer-related morbidity and mortality. This study aims to assess the completeness and reliability of colorectal cancer-related information available on the video website of Youku in mainland China. METHODS: Youku ( https://www.youku.com /) was searched on September 15, 2016 for the search terms colorectal cancer. Only Chinese videos were included. Two reviewers independently evaluate the videos for characteristics, information source and usefulness. Content was analysed under six categories (aetiology, anatomy, symptoms, preventions, treatments and prognosis). Completeness was evaluated with a checklist developed by the researchers. Any discrepancies were resolved by consensuses. SPSS software was used to analyze data. RESULTS: There were 242 videos with relevant information about colorectal cancer. The type of source were as follows: independent users, 118 (49%); health information web sites, 60 (25%); medical doctors, 31 (13%); news network, 22 (9%); and hospital/university, 11 (4%). In all, 57% of videos had useful information about colorectal cancer, 21% were misleading. Videos posted by medical doctors (P = 0.021) and health information web sites (p = 0.039) were less incomplete than videos by independent users. Of the Traditional Chinese medicine (TCM) videos, 97 (76%) had information about treatments of colorectal cancer. 30% TCM videos contain misleading information, whose misleading rate was higher than total's (21%). CONCLUSIONS: The colorectal cancer videos in mainland China represented by Youku varied base on ownership and content and information incompleteness were fairly high. It is necessary that professionals adapt to the advanced technology and think useful methods to solve the variable quality of information of internet video websites in mainland China.

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