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1.
Biol Reprod ; 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38900906

RESUMO

The Multispecies Ovary Tissue Histology Electronic Repository (MOTHER) is a publicly accessible repository of ovary histology images. MOTHER includes hundreds of images from nonhuman primates, as well as ovary histology images from an expanding range of other species. Along with an image, MOTHER provides metadata about the image, and for selected species, follicle identification annotations. Ongoing work includes assisting scientists with contributing their histology images, creation of manual and automated (via machine learning) processing pipelines to identify and count ovarian follicles in different stages of development, and the incorporation of that data into the MOTHER database (MOTHER-DB). MOTHER will be a critical data repository storing and disseminating high-value histology images that are essential for research into ovarian function, fertility, and intra-species variability.

2.
Biochem Genet ; 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38456973

RESUMO

Nurudea zhengii Ren was identified by aphid morphological characteristics as well as the gall shape and host plant species, and placed in the tribe Fordini (Hemiptera, Aphididae, Eriosomatinae). Here, its whole genome was firstly sequenced by a genome-skimming method and its mitochondrial genome (mitogenome) was assembled to examine its genetic variation and phylogenetic position. The complete mitogenome of Nurudea zhengii is 15,392 bp in length, and consists of 13 protein-coding genes, 22 tRNAs, two rRNAs and one D-loop region. The gene order follows the mitogenomes of the other Rhus gall aphids, and similarly has an AT bias with the content of 83.9%. The majority strand is A-skewed and C-skewed, and shows opposite skewness for G-skewed in the minority strands. The ratios of nonsynonymous to synonymous substitution rates of protein-coding genes are lower than one except for ATP8, which indicated that ATP8 was undergoing positive selection. Phylogenetic analysis among the Rhus gall aphids based on 13 protein-coding genes and two rRNA genes showed that N. zhengii was sister to N. shiraii, and then clustered with N. yanoniella as a group with high support value. The two species, N. shiraii and N. yanoniella, share the same host plant Rhus chinensis, while the host of N. zhengii is R. hypoleuca. However, the phylogenetic relationship indicated that the taxa sharing the same host plant were not absolutely clustered as the closest taxa at least at species level.

3.
Int J Mol Sci ; 25(8)2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38674159

RESUMO

Sepsis continues to overwhelm hospital systems with its high mortality rate and prevalence. A strategy to reduce the strain of sepsis on hospital systems is to develop a diagnostic/prognostic measure that identifies patients who are more susceptible to septic death. Current biomarkers fail to achieve this outcome, as they only have moderate diagnostic power and limited prognostic capabilities. Sepsis disrupts a multitude of pathways in many different organ systems, making the identification of a single powerful biomarker difficult to achieve. However, a common feature of many of these perturbed pathways is the increased generation of reactive oxygen species (ROS), which can alter gene expression, changes in which may precede the clinical manifestation of severe sepsis. Therefore, the aim of this study was to evaluate whether ROS-related circulating molecular signature can be used as a tool to predict sepsis survival. Here we created a ROS-related gene signature and used two Gene Expression Omnibus datasets from whole blood samples of septic patients to generate a 37-gene molecular signature that can predict survival of sepsis patients. Our results indicate that peripheral blood gene expression data can be used to predict the survival of sepsis patients by assessing the gene expression pattern of free radical-associated -related genes in patients, warranting further exploration.


Assuntos
Espécies Reativas de Oxigênio , Sepse , Humanos , Sepse/genética , Sepse/mortalidade , Sepse/sangue , Prognóstico , Espécies Reativas de Oxigênio/metabolismo , Biomarcadores , Transcriptoma , Perfilação da Expressão Gênica , Radicais Livres/metabolismo , Masculino , Feminino , Pessoa de Meia-Idade
4.
Int J Paediatr Dent ; 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38173170

RESUMO

BACKGROUND: Children affected by severe early childhood caries (S-ECC) usually need comprehensive caries treatment due to the extensive of caries. How the oral microbiome changes after caries therapy within the short-term warrant further study. AIM: This study aimed to investigate the short-term impact of comprehensive caries treatment on the supragingival plaque microbiome of S-ECC children. DESIGN: Thirty-three children aged 2-4 years with severe caries (dt > 7) were recruited. Comprehensive caries treatment was performed under general anesthesia in one session and included restoration, pulp treatment, extraction, and fluoride application. Supragingival plaque was sampled pre- and 1-month posttreatment. The genomic DNA of the supragingival plaque was extracted, and bacterial 16S ribosomal RNA gene sequencing was performed. RESULTS: Our data showed that the microbial community evenness significantly decreased posttreatment. Furthermore, comprehensive caries treatment led to more diverse microbial structures among the subjects. The interbacterial interactions reflected by the microbial community's co-occurrence network tended to be less complex posttreatment. Caries treatment increased the relative abundance of Corynebacterium matruchotii, Corynebacterium durum, Actinomyces naeslundii, and Saccharibacteria HMT-347, as well as Aggregatibacter HMT-458 and Haemophilus influenzae. Meanwhile, the relative abundance of Streptococcus mutans, three species from Leptotrichia, Neisseria bacilliformis, and Provotella pallens significantly decreased posttreatment. CONCLUSION: Our results suggested that comprehensive caries treatment may contribute to the reconstruction of a healthier supragingival microbiome.

5.
J Cell Mol Med ; 27(2): 204-221, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36583248

RESUMO

Necroptosis is a unique programmed death mechanism of necrotic cells. However, its role and specific mechanism in cancer remain unclear, and a systematic pan-cancer analysis of necroptosis is yet to be conducted. Thus, we performed a specific pan-cancer analysis using The Cancer Genome Atlas and Genotype-Tissue Expression databases to analyse necroptosis expression in terms of cancer prognosis, DNA methylation status, tumour mutative burden, microsatellite instability, immune cell infiltration in different types of cancer and molecular mechanisms. For the first time, we explored the correlation between necroptosis and immunotherapy prognosis. Thus, our study provides a relatively comprehensive understanding of the carcinogenicity of necroptosis in different types of cancer. It is suggested that necroptosis can be used to evaluate the sensitivity of different patients to immunotherapy and may become a potential target for tumour immunotherapy.


Assuntos
Necroptose , Neoplasias , Humanos , Necroptose/genética , Neoplasias/genética , Neoplasias/terapia , Metilação de DNA/genética , Bases de Dados Factuais , Imunoterapia , Microambiente Tumoral
6.
J Am Chem Soc ; 145(13): 7638-7647, 2023 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-36946888

RESUMO

The efficient and selective functionalization of icosahedral carboranes (C2B10H12) at the boron vertexes is a long-standing challenge owing to the presence of 10 inert B-H bonds in a similar chemical environment. Herein, we report a new reaction paradigm for direct B-H functionalization of icosahedral carboranes via B-H homolysis enabled by a nitrogen-centered radical-mediated hydrogen atom transfer (HAT) strategy. Both the HAT process of the carborane B-H bond and the resulting boron-centered carboranyl radical intermediate have been confirmed experimentally. The reaction occurs at the most electron-rich boron vertex with the lowest B-H bond dissociation energy (BDE). Using this strategy, diverse carborane derivatization, including thiolation, selenation, alkynylation, alkenylation, cyanation, and halogenation, have been achieved in satisfactory yields under a photoinitiated condition in a metal-free and redox-neutral fashion. Moreover, the synthetic utility of the current protocol was also demonstrated by both the scale-up reaction and the construction of carborane-based functional molecules. Therefore, this methodology opens a radical pathway to carborane functionalization, which is distinct from the B-H heterolytic mechanism in the traditional strategies.

7.
Acta Biochim Biophys Sin (Shanghai) ; 53(10): 1321-1332, 2021 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-34508625

RESUMO

The fusion gene of ABL1 is closely related to tumor proliferation, invasion, and migration. It has been reported recently that ABL1 itself is required for T-cell acute lymphoblastic leukemia (T-ALL) cell migration induced by CXCL12. Further experiments revealed that ABL1 inhibitor Nilotinib inhibited leukemia cell migration induced by CXCL12, indicating the possible application of Nilotinib in T-ALL leukemia treatment. However, the interacting proteins of ABL1 and the specific mechanisms of their involvement in this process need further investigation. In the present study, ABL1 interacting proteins were characterized and their roles in the process of leukemia cell migration induced by CXCL12 were investigated. Co-immunoprecipitation in combination with mass spectrometry analysis identified 333 proteins that interact with ABL1, including Cofilin1. Gene ontology analysis revealed that many of them were enriched in the intracellular organelle or cytoplasm, including nucleic acid binding components, transfectors, or co-transfectors. Kyoto Encyclopedia of Genes and Genomes analysis showed that the top three enriched pathways were translation, glycan biosynthesis, and metabolism, together with human diseases. ABL1 and Cofilin1 were in the same complex. Cofilin1 binds the SH3 domain of ABL1 directly; however, ABL1 is not required for the phosphorylation of Cofilin1. Molecular docking analysis shows that ABL1 interacts with Cofilin1 mainly through hydrogen bonds and ionic interaction between amino acid residues. The mobility of leukemic cells was significantly decreased by Cofilin1 siRNA. These results demonstrate that Cofilin1 is a novel ABL1 binding partner. Furthermore, Cofilin1 participates in the migration of leukemia cells induced by CXCL12. These data indicate that ABL1 and Cofilin1 are possible targets for T-ALL treatment.


Assuntos
Movimento Celular/imunologia , Cofilina 1/imunologia , Cofilina 1/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Proteínas Proto-Oncogênicas c-abl/imunologia , Proteínas Proto-Oncogênicas c-abl/metabolismo , Animais , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Quimiocina CXCL12/farmacologia , Cofilina 1/genética , Biologia Computacional , Citoesqueleto/metabolismo , Humanos , Masculino , Camundongos , Camundongos Endogâmicos DBA , Simulação de Acoplamento Molecular , Domínios Proteicos , Proteínas Proto-Oncogênicas c-abl/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-abl/genética , Pirimidinas/farmacologia , Linfócitos T/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto , Inibidor beta de Dissociação do Nucleotídeo Guanina rho/metabolismo
8.
Ecotoxicol Environ Saf ; 222: 112512, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34271502

RESUMO

Metallothioneins (MTs) are low molecular weight cysteine-rich proteins that bind to metals. Owing to their high cysteine (Cys) content, MTs are effective mediators of heavy metal detoxification. To enhance the heavy metal binding ability of MT from the freshwater crab Sinopotamon henanense (ShMT), sequence-based multiple sequence alignment (MSA) and structure-based molecular docking simulation (MDS) were conducted in order to identify amino acid residues that could be mutated to bolster such metal-binding activity. Site-directed mutagenesis was then used to modify the primary structure of ShMT, and the recombinant proteins were further enhanced using the SUMO fusion expression system to yield SUMO-ShMT1, SUMO-ShMT2, and SUMO-ShMT3 harboring one-, two-, and three- point mutations, respectively. The resultant modified proteins were primarily expressed in a soluble form and exhibited the ability to readily bind to heavy metals. Importantly, these modified proteins exhibited significantly enhanced heavy metal binding capacities, and they improved Cd2+, Cu2+ and Zn2+ tolerance and bioaccumulation in Escherichia coli (E. coli) in a manner dependent upon the number of introduced point mutations (SUMO-ShMT3 > SUMO-ShMT2 > SUMO-ShMT1 > SUMO-ShMT > control). Indeed, E. coli cells harboring the pET28a-SUMO-ShMT3 expression vector exhibited maximal Cd2+, Cu2+, and Zn2+ bioaccumulation that was increased by 1.86 ± 0.02-, 1.71 ± 0.03-, and 2.13 ± 0.02-fold relative to that in E. coli harboring the pET28a-SUMO-ShMT vector. The present study offers a basis for the preparation of genetically engineered bacteria that are better able to bioaccumulate and tolerate heavy metals, thus providing a foundation for biological heavy metal water pollution treatment.


Assuntos
Metalotioneína , Metais Pesados , Bioacumulação , Escherichia coli/genética , Escherichia coli/metabolismo , Metalotioneína/genética , Metalotioneína/metabolismo , Metais Pesados/toxicidade , Simulação de Acoplamento Molecular
9.
Eur Neurol ; 83(5): 458-467, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33027797

RESUMO

INTRODUCTION: The molecular pathogenesis of Alzheimer's disease (AD) is still not clear, and the relationship between gene expression profile for different brain regions has not been studied. OBJECTIVE: Bioinformatic analysis at the genetic level has become the best way for the pathogenesis research of AD, which can analyze the abovementioned relationship. METHODS: In this study, the datasets of AD were obtained from the Gene Expression Omnibus (GEO), and Qlucore Omics Explorer (QOE) software was used to screen differentially expressed genes of GSE36980 and GSE9770 and verify gene expression of GSE63060. The Gene Ontology (GO) function enrichment analysis of these selected genes was conducted by Database for Annotation, Visualization, and Integrated Discovery (DAVID), and then the gene/protein interaction network was established by STRING to find the related proteins. R language was used for drafting maps and plots. RESULTS: There were 20 differentially expressed genes related to AD selected from GSE36980 (p = 6.2e-6, q = 2.9422e-4) and GSE9770 (p = 3.3e-4, q = 0.016606). Their expression levels of the AD group were lower than those in the control group and varied among different brain regions. Cellular morphogenesis and establishment or maintenance of cell polarity were enriched, and LRRTM1 and RASAL1 were identified by the integration network. Moreover, the analysis of GSE63060 verified the expression level of LRRTM1 and RASAL1 in Alzheimer's patients, which was much lower than that in normal people aged >65 years. CONCLUSIONS: The pathogenesis of AD at molecular levels may link to cell membrane structures and signal transduction; hence, a list of 20 genes, including LRRTM1 and RASAL1,potentially are important for the discovery of treatment target or molecular marker of AD.


Assuntos
Doença de Alzheimer/genética , Transcriptoma , Idoso , Biologia Computacional , Perfilação da Expressão Gênica , Humanos , Mapas de Interação de Proteínas/genética , Transdução de Sinais/genética
10.
Phys Chem Chem Phys ; 21(39): 21726-21737, 2019 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-31372612

RESUMO

Graphene (GN) nanofillers have been widely used to enhance the overall performance of polymer composites due to their various superior properties, which strongly rely on the uniform dispersion and strong interfacial bonding of GN with high-quality polymer matrices. In the present study, the strengthening and functional effects of polydopamine-coated edge-carboxylated graphene (p-ECG) on the mechanical, moisture-barrier and electromagnetic properties of epoxy (EP)-based composites were systematically evaluated. p-ECG was successfully prepared via one-step high-pressure ball milling through the edge-selective functionalization and exfoliation of pristine graphite in the presence of dry ice, followed by synchronous reduction and coating via the mild oxidative polymerization of mussel-inspired dopamine. p-ECG showed prominent advantages of a small sheet size, excellent dispersibility and high chemical reactivity in the EP matrix. Obvious enhancements were achieved in the tensile and flexural properties and moisture-barrier performance of EP composites as well as the interlaminar shear strength (ILSS) and transverse fiber bundle tensile (TFBT) strength of carbon fiber (CF)/EP composites, which confirmed the excellent dispersion and chemically strengthened interfacial bonding of p-ECG in the EP matrix. More importantly, p-ECG introduced onto the surface of desized CF led to significant enhancement in the electromagnetic interference (EMI) shielding capability of CF/EP composites, which was primarily ascribed to the polarization relaxation effect induced by the defects and functional groups in p-ECG as well as the increase in electrical conductivity derived from the "bridging effect" of p-ECG. Specifically, with p-ECG content of 0.5 wt%, the increments in tensile strength, TFBT strength, shielding effectiveness (total, SET) and shielding effectiveness (reflection loss, SER) were as high as 33.3, 34.3, 31.3 and 71.0%, respectively.

11.
Appl Opt ; 58(19): 5136-5142, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31503606

RESUMO

Detection accuracy is an important performance indicator of ground-based telescopes and is affected mainly by pointing error, geometric distortion of the optical system, and parameter errors caused by machining error and installation error. To improve detection accuracy, a modified algorithm based on a simulated annealing algorithm is proposed in this paper; this algorithm is able to correct pointing, derive a geometric distortion solution, and re-estimate some parameters of telescopes simultaneously. The efficiency of the proposed method is verified by using the observation data of the telescope, whose aperture is 600 mm under two distortion models (the physical model and polynomial fitting model). The results show that the method presented in this paper can effectively solve the problem of nonconvergence of the distortion solution with a pointing error. The final angle error under the polynomial fitting model is 1.07″, and the pixel error is 0.06 pixels; the errors under the physical model are 1.08″ and 0.07 pixels. The correction effect under the two distortion models is basically the same, but the averaged operation speed based on the physical model is 19.45% faster.

12.
Ecotoxicol Environ Saf ; 169: 457-463, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30472469

RESUMO

Metallothioneins (MTs) are a super-family of ubiquitous, low-molecular-weight, cysteine-rich and metal-binding proteins. They are thought to play a predominant role in mediating metal metabolism and antioxidation. However, the accurate functions of MTs remain unclear in the physiological processes due to native proteins deficiency and little information of their metal-binding character. Freshwater crab Sinopotamon henanense is a decapod crustacean widely distributed in northern China, in which only one MT isoform (ShMT) has been reported so far. In order to shed light on the accurate role of ShMT, a novel recombinant ShMT in native form was over-expressed by phoA secreted expression system in Escherichia coli (E. coli). Then the ShMT proteins were purified using a one-step gentle immunoaffinity chromatography with a polyol-responsive mAb (PR-mAb) to ShMT, which was generated by conventional hybridoma technology followed by ELISA-elution. The Zn-, Cu-, and Cd-ShMT complexes were prepared by recombinant synthesis in metal-enriched media and reconstitution with metal ions, respectively. Further analysis about metal-binding capacity showed recombinant ShMT has high ability to bind Zn, Cu and Cd metals, although the recombinantly expressed and reconstituted metal-ShMT complexes have different metal-to-protein stoichiometry. Moreover, the affinity of recombinant protein for metal ions has been analyzed using competitive reaction with 5, 5-dithiobis (2-nitrobenzoic acid) (DTNB). The results demonstrated the affinity of recombinant ShMT for metals was as follows: Cu>Cd>Zn. In summary, the experimental procedure we have developed facilitates production of recombinant ShMT with native characteristics for further research and the study of metal-binding ability could help further clarify the accurate functions of ShMT.


Assuntos
Braquiúros/metabolismo , Regulação da Expressão Gênica , Metalotioneína/genética , Metais Pesados/metabolismo , Proteínas Recombinantes/genética , Sequência de Aminoácidos , Animais , China , Cromatografia de Afinidade , Ensaio de Imunoadsorção Enzimática , Escherichia coli/genética , Escherichia coli/metabolismo , Metalotioneína/metabolismo , Ligação Proteica , Isoformas de Proteínas , Proteínas Recombinantes/metabolismo
13.
Ecotoxicol Environ Saf ; 181: 301-307, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31202929

RESUMO

Metallothioneins (MTs) are a family of low molecular weight, cysteine-rich, metal-binding proteins, which play important roles in metal homeostasis and heavy metal detoxification. In our previous study, a novel full length MT cDNA was successfully cloned from the freshwater crab (Sinopotamon henanense). In the present study, tandem repeats of two and three copies of the crab MT gene were integrated by overlap extension PCR (SOE-PCR) and expressed in Escherichia coli. The SUMO fusion expression system was adopted to increase the stability and solubility of the recombinant MT proteins. The recombinant proteins were purified and their metal-binding abilities were further analyzed by the ultraviolet absorption spectral scan. Furthermore, the metal tolerance and bioaccumulation of E. coli cells expressing oligomeric MTs were determined. Results showed that the recombinant plasmids pET28a-SUMO-2MT and pET28a-SUMO-3MT were successfully constructed. SDS-PAGE analysis showed that the SUMO-2MT and SUMO-3MT were expressed mainly in the soluble forms. Oligomeric MTs expression significantly enhanced Cu, Cd or Zn tolerance and accumulation in E. coli in the order: SUMO-3MT˃SUMO-2MT˃SUMO-MT˃control. Cells harboring pET28a-SUMO -3MT exhibited the highest Cu, Cd or Zn bioaccumulation at 5.8-fold, 3.1-fold or 6.7-fold higher than that of the control cells. Our research could lay a foundation for large-scale preparation of MTs and provide a scientific basis for bioremediation of heavy metal pollution by oligomeric MTs.


Assuntos
Escherichia coli/genética , Metalotioneína/genética , Metais Pesados/metabolismo , Animais , Braquiúros/genética , Escherichia coli/efeitos dos fármacos , Escherichia coli/metabolismo , Metalotioneína/metabolismo , Metais Pesados/toxicidade , Proteínas Recombinantes de Fusão/metabolismo
14.
Sensors (Basel) ; 19(2)2019 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-30658462

RESUMO

Scanning mirrors appear to be key components in optoelectronic systems for line-of-sight (LOS) stabilization. For improving the angular accuracy of a scanning mirror based on the eddy current displacement sensor measurement, an angular error-correction method is proposed and demonstrated. A mathematic angular error model with physical parameters was developed, and the cross-validation method was employed to determine the reasonable order of the Maclaurin series used in the error model, which increased the exactitude and robustness of the correction method. The error parameters were identified by accurately fitting the calibrated angular errors with the error model, which showed excellent error prediction performance. Based on the angular calculation model corrected by the error model, the closed-loop control system was established to obtain accurate deflection angles. Experimental results show that within the deflection angle of ±1.5 deg, the angular accuracy was improved from 0.28 deg to less than 1.1 arcsec, and the standard deviation for six measurements was less than 1.2 arcsec, which indicates that the angle correction method was effective in improving the linearity of the eddy current sensors and reducing the influence of manufacturing and installation errors.

15.
Zhongguo Zhong Yao Za Zhi ; 44(15): 3253-3260, 2019 Aug.
Artigo em Zh | MEDLINE | ID: mdl-31602880

RESUMO

Flavonoids are a group of secondary metabolites found in plants. They have many pharmacological functions and play an important role in Chinese sumac( Rhus chinensis),which is a well-known traditional Chinese medicinal plant. Chalcone isomerase( CHI,EC 5. 5. 1. 6) is one of the key enzymes in the flavonoids biosynthesis pathway. In this paper,the full-length c DNA sequence encoding the chalcone isomerase from R. chinensis( designated as Rc CHI) was cloned by RT-PCR and rapid-amplification of c DNA Ends( RACE). The Rc CHI c DNA sequence was 1 058 bp and the open reading frame( ORF) was 738 bp. The ORF predicted to encode a 245-amino acid polypeptide. Rc CHI gene contained an intron and two exons. The sequence alignments revealed Rc CHI shared47. 1%-71. 6% identity with the homologues in other plants. Real-time PCR analysis showed that the total flavonoid levels were positively correlated with tissue-specific expressions of Rc CHI mRNA in different tissues. The recombinant protein was successfully expressed in an Escherichia coli strain with the p GEX-6 P-1 vector. In this paper,the CHI gene was cloned and characterized in the family of Anacardiaceae and will help us to obtain better knowledge of the flavonoids biosynthesis of the flavonoid compounds in R. chinensis.


Assuntos
Flavonoides/biossíntese , Liases Intramoleculares/genética , Rhus/enzimologia , Clonagem Molecular , DNA Complementar , Plantas Medicinais/enzimologia , Plantas Medicinais/genética , Rhus/genética
16.
Am J Respir Cell Mol Biol ; 59(1): 36-44, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29337590

RESUMO

Nicotinamide phosphoribosyltransferase (NAMPT) exists as both intracellular NAMPT and extracellular NAMPT (eNAMPT) proteins. eNAMPT is secreted into the blood and functions as a cytokine/enzyme (cytozyme) that activates NF-κB signaling via ligation of Toll-like receptor 4 (TLR4), further serving as a biomarker for inflammatory lung disorders such as acute respiratory distress syndrome. In contrast, intracellular NAMPT is involved in nicotinamide mononucleotide synthesis and has been implicated in the regulation of cellular apoptosis, although the exact mechanisms for this regulation are poorly understood. We examined the role of NAMPT in TNF-α-induced human lung endothelial cell (EC) apoptosis and demonstrated that reduced NAMPT expression (siRNA) increases EC susceptibility to TNF-α-induced apoptosis as reflected by PARP-1 cleavage and caspase-3 activation. In contrast, overexpression of NAMPT served to reduce degrees of TNF-α-induced EC apoptosis. Inhibition of nicotinamide mononucleotide synthesis by FK866 (a selective NAMPT enzymatic inhibitor) failed to alter TNF-α-induced human lung EC apoptosis, suggesting that NAMPT-dependent NAD+ generation is unlikely to be involved in regulation of TNF-α-induced EC apoptosis. We next confirmed that TNF-α-induced EC apoptosis is attributable to NAMPT secretion into the EC culture media and subsequent eNAMPT ligation of TLR4 on the EC membrane surface. Silencing of NAMPT expression, direct neutralization of secreted eNAMPT by an NAMPT-specific polyclonal antibody (preventing TLR4 ligation), or direct TLR4 antagonism all served to significantly increase EC susceptibility to TNF-α-induced EC apoptosis. Together, these studies provide novel insights into NAMPT contributions to lung inflammatory events and to novel mechanisms of EC apoptosis regulation.


Assuntos
Apoptose/efeitos dos fármacos , Citocinas/metabolismo , Células Endoteliais/enzimologia , Pulmão/patologia , Nicotinamida Fosforribosiltransferase/metabolismo , Fator de Necrose Tumoral alfa/farmacologia , Biomarcadores/metabolismo , Citocinas/farmacologia , Citoproteção/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , Humanos , NAD/metabolismo , Nicotinamida Fosforribosiltransferase/farmacologia , Proteínas Recombinantes/farmacologia
17.
BMC Cancer ; 18(1): 67, 2018 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-29321004

RESUMO

BACKGROUND: Small GTP binding protein Rac1 is a component of NADPH oxidases and is essential for superoxide-induced cell death. Rac1 is activated by guanine nucleotide exchange factors (GEFs), and this activation can be blocked by regulator of chromosome condensation 2 (RCC2), which binds the switch regions of Rac1 to prevent access from GEFs. METHODS: Three cancer cell lines with up- or down-regulation of RCC2 were used to evaluate cell proliferation, apoptosis, Rac1 signaling and sensitivity to a group of nine chemotherapeutic drugs. RCC2 expression in lung cancer and ovarian cancer were studied using immunochemistry stain of tumor tissue arrays. RESULTS: Forced RCC2 expression in tumor cells blocked spontaneous- or Staurosporine (STS)-induced apoptosis. In contrast, RCC2 knock down in these cells resulted in increased apoptosis to STS treatment. The protective activity of RCC2 on apoptosis was revoked by a constitutively activated Rac1, confirming a role of RCC2 in apoptosis by regulating Rac1. In an immunohistochemistry evaluation of tissue microarray, RCC2 was over-expressed in 88.3% of primary lung cancer and 65.2% of ovarian cancer as compared to non-neoplastic lung and ovarian tissues, respectively. Because chemotherapeutic drugs can kill tumor cells by activating Rac1/JNK pathway, we suspect that tumors with RCC2 overexpression would be more resistant to these drugs. Tumor cells with forced RCC2 expression indeed had significant difference in drug sensitivity compared to parental cells using a panel of common chemotherapeutic drugs. CONCLUSIONS: RCC2 regulates apoptosis by blocking Rac1 signaling. RCC2 expression in tumor can be a useful marker for predicting chemotherapeutic response.


Assuntos
Proteínas Cromossômicas não Histona/genética , Fatores de Troca do Nucleotídeo Guanina/genética , Neoplasias Pulmonares/genética , Neoplasias Ovarianas/genética , Proteínas rac1 de Ligação ao GTP/genética , Apoptose/efeitos dos fármacos , Biomarcadores Farmacológicos , Resistencia a Medicamentos Antineoplásicos/genética , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células HeLa , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/patologia , Estaurosporina/farmacologia
18.
PLoS Genet ; 11(7): e1005368, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26162102

RESUMO

Spermatogenesis consists broadly of three phases: proliferation of diploid germ cells, meiosis, and finally extensive differentiation of the haploid cells into effective delivery vehicles for the paternal genome. Despite detailed characterization of many haploid developmental steps leading to sperm, only fragmentary information exists on the control of gene expression underlying these processes. Here we report that the RFX2 transcription factor is a master regulator of genes required for the haploid phase. A targeted mutation of Rfx2 was created in mice. Rfx2-/- mice are perfectly viable but show complete male sterility. Spermatogenesis appears to progress unperturbed through meiosis. However, haploid cells undergo a complete arrest in spermatid development just prior to spermatid elongation. Arrested cells show altered Golgi apparatus organization, leading to a deficit in the generation of a spreading acrosomal cap from proacrosomal vesicles. Arrested cells ultimately merge to form giant multinucleated cells released to the epididymis. Spermatids also completely fail to form the flagellar axoneme. RNA-Seq analysis and ChIP-Seq analysis identified 139 genes directly controlled by RFX2 during spermiogenesis. Gene ontology analysis revealed that genes required for cilium function are specifically enriched in down- and upregulated genes showing that RFX2 allows precise temporal expression of ciliary genes. Several genes required for cell adhesion and cytoskeleton remodeling are also downregulated. Comparison of RFX2-regulated genes with those controlled by other major transcriptional regulators of spermiogenesis showed that each controls independent gene sets. Altogether, these observations show that RFX2 plays a major and specific function in spermiogenesis.


Assuntos
Proteínas de Ligação a DNA/genética , Infertilidade Masculina/genética , Espermátides/citologia , Espermatócitos/citologia , Espermatogênese/genética , Fatores de Transcrição/genética , Animais , Apoptose/genética , Adesão Celular/genética , Cílios/genética , Cílios/fisiologia , Modulador de Elemento de Resposta do AMP Cíclico/genética , Citoesqueleto/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fatores de Transcrição de Fator Regulador X , Espermatogênese/fisiologia , Fatores Associados à Proteína de Ligação a TATA/genética , Fator de Transcrição TFIID/genética , Transcrição Gênica/genética
19.
Cancer Cell Int ; 17: 14, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28149200

RESUMO

BACKGROUND: MicroRNAs are a class of small non-coding RNAs that are involved in many important physiological and pathological processes by regulating gene expression negatively. The purpose of this study was to investigate the effect of miR-32 on cell proliferation, migration and apoptosis and to determine the functional connection between miR-32 and FBXW7 in breast cancer. METHODS: In this study, quantitative RT-PCR was used to evaluate the expression levels of miR-32 in 27 breast cancer tissues, adjacent normal breast tissues and human breast cancer cell lines. The biological functions of miR-32 in MCF-7 breast cancer cells were determined by cell proliferation, apoptosis assays and wound-healing assays. In addition, the regulation of FBXW7 by miR-32 was assessed by qRT-PCR, Western blot and luciferase reporter assays. RESULTS: MiR-32 was frequently overexpressed in breast cancer tissue samples and cell lines as was demonstrated by qRT-PCR. Moreover, the up-regulation of miR-32 suppressed apoptosis and promoted proliferation and migration, whereas down-regulation of miR-32 showed an opposite effect. Dual-luciferase reporter assays showed that miR-32 binds to the 3'-untranslated region of FBXW7, suggesting that FBXW7 is a direct target of miR-32. Western blot analysis showed that over-expression of miR-32 reduced FBXW7 protein level. Furthermore, an inverse correlation was found between the expressions of miR-32 and FBXW7 mRNA levels in breast cancer tissues. Knockdown of FBXW7 promoted proliferation and motility and suppressed apoptosis in MCF-7 cells. CONCLUSIONS: Taken together, the present study suggests that miR-32 promotes proliferation and motility and suppresses apoptosis of breast cancer cells through targeting FBXW7.

20.
Zhongguo Zhong Yao Za Zhi ; 42(11): 2052-2057, 2017 Jun.
Artigo em Zh | MEDLINE | ID: mdl-28822147

RESUMO

Plate assay and spore germination method were used to study the chemotaxis response of Alternaria panax to arginine, glutamic acid, aspartic acid and threonine. The result showed that the optimum temperature of A. panax chemotaxis response to four amino acids were all 25 ℃. And chemotaxis responses of A. panax were different under conditions of different concentration and pH value. The chemotaxin reached to the highest under the condition of 2 mg•L⁻¹ and pH value was 7 for arginine, glutamic acid and threonine while 20 mg•L⁻¹ and pH value was 6 for aspartic acid . The data of chemotactic migration index (CMI) were 1.24, 1.38, 1.27, 1.31 and chemotactic growth rates(CGR) were 0.451 0, 0.353 0, 0.381 3, 0.228 8 and spores germination rates(SGR) were 57.33%,63%,56.67%,58% and the dry weight of mycelial (DWM) were 372.9, 348.5, 314.4, 390.2 mg•L⁻¹ respectively. It indicated that the low and middle concentration of amino acid had significant promoting effect on chemotaxis response of A. panax. As important substances generated in ginseng root, amino acids exhibited an efficient chemotactic effect on A. panax, and some even show inhibition effect under high concentration.


Assuntos
Alternaria/efeitos dos fármacos , Aminoácidos/farmacologia , Quimiotaxia , Panax/química , Raízes de Plantas/química , Alternaria/citologia
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