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1.
BMC Plant Biol ; 24(1): 61, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38253992

RESUMO

BACKGROUND: Leaf coloration in plants, attributed to anthocyanin compounds, plays a crucial role in various physiological functions, and also for pharmaceutical and horticultural uses. However, the molecular mechanisms governing leaf coloration and the physiological significance of anthocyanins in leaves remain poorly understood. RESULTS: In this study, we investigated leaf color variation in two closely related mulberry genotypes, one with purplish-red young leaves (EP) and another with normal leaf color (EW). We integrated transcriptomic and metabolomic approaches to gain insights into the metabolic and genetic basis of purplish-red leaf development in mulberry. Our results revealed that flavonoid biosynthesis, particularly the accumulation of delphinidin-3-O-glucoside, is a key determinant of leaf color. Additionally, the up-regulation of CHS genes and transcription factors, including MYB family members, likely contributes to the increased flavonoid content in purplish-red leaves. CONCLUSION: These findings enhance our understanding of the molecular mechanisms responsible for the purplish coloration observed in mulberry leaves and also offer supporting evidence for the hypothesis that anthocyanins serve a protective function in plant tissues until the processes of light absorption and carbon fixation reach maturity, thereby ensuring a balanced equilibrium between energy capture and utilization.


Assuntos
Morus , Morus/genética , Antocianinas , Genótipo , Flavonoides , Folhas de Planta/genética
2.
Oncologist ; 28(5): 449-452, 2023 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-36913260

RESUMO

Glioblastoma (GBM) is the most common primary brain tumor, and patients with GBM have a universally poor prognosis. Genomic profiling has detected epidermal growth factor receptor (EGFR) gene alterations in more than half of GBMs. Major genetic events include amplification and mutation of EGFR. Interestingly, we identified an EGFR p.L858R mutation in a patient with recurrent GBM for the first time. Based on the genetic testing results, almonertinib combined with anlotinib and temozolomide was administered and obtained 12 months of progression-free survival after the diagnosis of recurrence as the fourth-line treatment. This is the first report that an EGFR p.L858R mutation was identified in a patient with recurrent GBM. Furthermore, this case report represents the first study applying the third-generation TKI inhibitor almonertinib in the treatment of recurrent GBM. The results of this study indicate that EGFR might be a new marker for the treatment of GBM with almonertinib.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Humanos , Temozolomida/farmacologia , Temozolomida/uso terapêutico , Glioblastoma/tratamento farmacológico , Glioblastoma/genética , Receptores ErbB/genética , Mutação , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo
3.
Plant J ; 107(2): 360-376, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33901334

RESUMO

The control of chlorophyll (Chl) synthesis in angiosperms depends on the light-operating enzyme protochlorophyllide oxidoreductase (POR). The interruption of Chl synthesis during darkness requires suppression of the synthesis of 5-aminolevulinic acid (ALA), the first precursor molecule specific for Chl synthesis. The inactivation of glutamyl-tRNA reductase (GluTR), the first enzyme in tetrapyrrole biosynthesis, accomplished the decreased ALA synthesis by the membrane-bound protein FLUORESCENT (FLU) and prevents overaccumulation of protochlorophyllide (Pchlide) in the dark. We set out to elucidate the molecular mechanism of FLU-mediated inhibition of ALA synthesis, and explored the role of each of the three structural domains of mature FLU, the transmembrane, coiled-coil and tetratricopeptide repeat (TPR) domains, in this process. Efforts to rescue the FLU knock-out mutant with truncated FLU peptides revealed that, on its own, the TPR domain is insufficient to inactivate GluTR, although tight binding of the TPR domain to GluTR was detected. A truncated FLU peptide consisting of transmembrane and TPR domains also failed to inactivate GluTR in the dark. Similarly, suppression of ALA synthesis could not be achieved by combining the coiled-coil and TPR domains. Interaction studies revealed that binding of GluTR and POR to FLU is essential for inhibiting ALA synthesis. These results imply that all three FLU domains are required for the repression of ALA synthesis, in order to avoid the overaccumulation of Pchlide in the dark. Only complete FLU ensures the formation of a membrane-bound ternary complex consisting at least of FLU, GluTR and POR to repress ALA synthesis.


Assuntos
Proteínas de Arabidopsis/química , Aldeído Oxirredutases/metabolismo , Ácido Aminolevulínico/metabolismo , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Clorofila/metabolismo , Escuridão , Etanol/farmacologia , Expressão Gênica/efeitos dos fármacos , Luz , Plantas Geneticamente Modificadas , Plântula/metabolismo
4.
Lab Invest ; 101(1): 104-115, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32873879

RESUMO

Angiogenesis is involved in ischemic heart disease as well as the prognosis of heart failure (HF), and endothelial cells are the main participants in angiogenesis. In this study, we found that miR-221-3p is highly expressed in vascular tissue, especially in endothelial cells, and increased miR-221-3p was observed in heart tissue of HF patients and transverse aortic constriction (TAC)-induced HF mice. To explore the role of miR-221-3p in endothelial cells, microRNA (miRNA) mimics and inhibitors were employed in vitro. Overexpression of miR-221-3p inhibited endothelial cell proliferation, migration, and cord formation in vitro, while inhibition of miR-221-3p showed the opposite effect. Anti-argonaute 2 (Ago2) coimmunoprecipitation, dual-luciferase reporter assay, and western blotting were performed to verify the target of miR-221-3p. Hypoxia-inducible factor-1α (HIF-1α) was identified as a miR-221-3p target, and the adverse effects of miR-221-3p on endothelial cells were alleviated by HIF-1α re-expression. In vivo, a mouse model of hindlimb ischemia (HLI) was developed to demonstrate the effect of miR-221-3p on angiogenesis. AntagomiR-221-3p increased HIF-1α expression and promoted angiogenesis in mouse ischemic hindlimbs. Using the TAC model, we clarified that antagomiR-221-3p improved cardiac function in HF mice by promoting cardiac angiogenesis. Furthermore, serum miR-221-3p was detected to be negatively correlated with heart function in chronic heart failure (CHF) patients. Our results conclude that miR-221-3p inhibits angiogenesis of endothelial cells by targeting HIF-1α and that inhibition of miR-221-3p improves cardiac function of TAC-induced HF mice. Furthermore, miR-221-3p might be a potential prognostic marker of HF.


Assuntos
Insuficiência Cardíaca/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , MicroRNAs/metabolismo , Neovascularização Fisiológica , Animais , Células Endoteliais/fisiologia , Regulação da Expressão Gênica , Células HEK293 , Membro Posterior/irrigação sanguínea , Células Endoteliais da Veia Umbilical Humana , Humanos , Masculino , Camundongos Endogâmicos C57BL
5.
Plant J ; 97(3): 517-529, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30362619

RESUMO

Fluorescent in blue light (FLU) is a negative regulator involved in dark repression of 5-aminolevulinic acid (ALA) synthesis and interacts with glutamyl-tRNA reductase (GluTR), the rate-limiting enzyme of tetrapyrrole biosynthesis. In this study, we investigated FLU's regulatory function in light-exposed FLU-overexpressing (FLUOE) Arabidopsis lines and under fluctuating light intensities in wild-type (WT) and flu seedlings. FLUOE lines suppress ALA synthesis in the light, resulting in reduced chlorophyll content, but more strongly in low and high light than in medium growth light. This situation indicates that FLU's impact on chlorophyll biosynthesis depends on light intensity. FLU overexpressors contain strongly increased amounts of mainly membrane-associated GluTR. These findings correlate with FLU-dependent localization of GluTR to plastidic membranes and concomitant inhibition, such that only the soluble GluTR fraction is active. The overaccumulation of membrane-associated GluTR indicates that FLU binding enhances GluTR stability. Interestingly, under fluctuating light, the leaves of flu mutants contain less chlorophyll compared with WT and become necrotic. We propose that FLU is basically required for fine-tuned ALA synthesis. FLU not only mediates dark repression of ALA synthesis, but functions also to control balanced ALA synthesis under variable light intensities to ensure the adequate supply of chlorophyll.


Assuntos
Aldeído Oxirredutases/metabolismo , Ácido Aminolevulínico/metabolismo , Proteínas de Arabidopsis/metabolismo , Arabidopsis/genética , Aldeído Oxirredutases/genética , Arabidopsis/enzimologia , Arabidopsis/efeitos da radiação , Proteínas de Arabidopsis/genética , Clorofila/metabolismo , Fluorescência , Regulação da Expressão Gênica de Plantas/efeitos da radiação , Membranas Intracelulares/enzimologia , Luz , Folhas de Planta/enzimologia , Folhas de Planta/genética , Folhas de Planta/efeitos da radiação , Plantas Geneticamente Modificadas , Plastídeos/enzimologia , Transporte Proteico , Plântula/enzimologia , Plântula/genética , Plântula/efeitos da radiação
6.
Am J Nephrol ; 51(5): 401-410, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32320986

RESUMO

BACKGROUND: Human cellular repressor of E1A-stimulated genes (CREG) is a secreted glycoprotein that attenuates angiotensin II-induced hypertension, alleviates myocardial fibrosis, and improves heart function. However, the role of CREG in high-salt (HS) diet-induced hypertensive nephropathy is unclear. METHODS: To determine the effects and molecular mechanisms of CREG in HS diet-induced hypertensive nephropathy, we established a hypertensive nephropathy animal model in Dahl salt-sensitive (SS) rats fed a HS diet (8% NaCl, n = 20) for 8 weeks. At week 4 of HS loading, these rats were administered recombinant CREG (reCREG; 35 µg/kg·day, n = 5) and saline (n = 5) via subcutaneously implanted pumps and were also administered the vasodilator hydralazine (20 mg/kg·day, n = 5) in drinking water. We used hematoxylin and eosin staining, Masson's trichrome staining, immunohistochemical labeling, western blotting, RT-PCR, and Tunel staining to determine the signaling pathways of CREG in HS diet-induced hypertensive nephropathy. RESULTS: After 8 weeks of HS intake, the Dahl SS rats developed renal dysfunction and severe renal fibrosis associated with reductions of 78 and 67% in CREG expression, respectively, at both mRNA and protein levels in the kidney. Administration of reCREG improved renal function and relieved renal fibrosis. Administration of CREG also inhibited monocyte infiltration and reduced apoptosis in the kidney cells. CREG overexpression upregulated forkhead box P1 expression and inhibited the transforming growth factor-ß1 signaling pathway. CONCLUSION: Our study shows that CREG protected the kidney against HS-diet-induced renal damage and provides new insights into the mechanisms underlying kidney injury.


Assuntos
Hipertensão Renal/tratamento farmacológico , Rim/patologia , Nefrite/tratamento farmacológico , Proteínas Repressoras/administração & dosagem , Cloreto de Sódio na Dieta/efeitos adversos , Animais , Apoptose/efeitos dos fármacos , Modelos Animais de Doenças , Fibrose , Humanos , Hipertensão Renal/etiologia , Hipertensão Renal/patologia , Rim/efeitos dos fármacos , Masculino , Nefrite/etiologia , Nefrite/patologia , Ratos , Ratos Endogâmicos Dahl , Proteínas Recombinantes/administração & dosagem , Proteínas Repressoras/análise , Proteínas Repressoras/metabolismo
7.
J Sci Food Agric ; 99(4): 1997-2004, 2019 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-30298617

RESUMO

BACKGROUND: Photosynthetic pigments perform critical physiological functions in tea plants. Their content is an essential indicator of photosynthetic efficiency and nutritional status. The present study aimed to predict chlorophyll a (Chl a), chlorophyll b (Chl b), total chlorophyll (total Chl), and carotenoid (Car) content in tea leaves under different levels of nitrogen treatment using hyperspectral imaging (HSI) in combination with variable selection algorithms. RESULTS: A total of 150 samples were collected and scanned using the HSI system. The mean spectrum in the region of interest (ROI) was extracted, and the pigment content was measured by traditional chemical methods. Five and seven optimal wavelengths (OWs) were selected using the regression coefficients (RCs) of partial least squares regression (PLSR) and the second-derivative (2-Der), respectively. The optimal 2-Der-PLSR models for Chl a, Chl b, total Chl, and Car performed remarkably well based on seven OWs with correlation coefficients of prediction (RP ) of 0.9337, 0.9322, 0.9333 and 0.9036, root mean square errors in prediction (RMSEP) of 0.1100, 0.0511, 0.1620, and 0.0300 mg g-1 , respectively. CONCLUSION: The results of this study revealed that HSI combined with variable selection method can be employed as a rapid and accurate method for predicting the content of pigments in tea plants. © 2018 Society of Chemical Industry.


Assuntos
Camellia sinensis/metabolismo , Carotenoides/análise , Clorofila A/análise , Clorofila/análise , Folhas de Planta/química , Análise Espectral/métodos , Algoritmos , Camellia sinensis/química , Carotenoides/metabolismo , Clorofila/metabolismo , Clorofila A/metabolismo , Cor , Fertilizantes/análise , Análise dos Mínimos Quadrados , Nitrogênio/análise , Nitrogênio/metabolismo , Pigmentos Biológicos/análise , Pigmentos Biológicos/metabolismo , Folhas de Planta/metabolismo
8.
Plant Cell Physiol ; 59(11): 2204-2213, 2018 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-30032295

RESUMO

The synthesis of 5-aminolevulinic acid (ALA) determines adequate amounts of metabolites for the tetrapyrrole biosynthetic pathway. Glutamyl-tRNA reductase (GluTR) catalyzes the rate-limiting step of ALA synthesis and was previously considered to be exclusively localized in the chloroplast stroma of light-exposed plants. To assess the intraplastidic localization of GluTR, we developed a fast separation protocol of soluble and membrane-bound proteins and reassessed the subplastidal allocation of GluTR in stroma and membrane fractions of Arabidopsis plants grown under different light regimes as well as during de-etiolation and dark incubations. Under the examined conditions, the amount of stroma-localized GluTR correlated with the ALA synthesis rate. The transfer to dark repression of ALA synthesis resulted in a loss of soluble GluTR. Arabidopsis mutants lacking one of the GluTR-interacting factors FLUORESCENT (FLU), the GluTR-binding protein (GBP) or ClpC, a chaperone of the Clp protease system, were applied to examine the amount of GluTR and its distribution to the stroma or membrane in darkness and light. Taking into consideration the different compartmental allocation of GluTR, its stability and ALA synthesis rates, the post-translational impact of these regulatory factors on GluTR activity and plastidic sublocalization is discussed.


Assuntos
Aldeído Oxirredutases/metabolismo , Ácido Aminolevulínico/metabolismo , Membrana Celular/enzimologia , Cloroplastos/enzimologia , Arabidopsis/enzimologia , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Membrana Celular/metabolismo , Cloroplastos/metabolismo , Escuridão , Luz , Plântula/crescimento & desenvolvimento
9.
J Sci Food Agric ; 98(12): 4659-4664, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29607500

RESUMO

BACKGROUND: Nitrogen (N) fertilizer plays an important role in tea plantation management, with significant impacts on the photosynthetic capacity, productivity and nutrition status of tea plants. The present study aimed to establish a method for the discrimination of N fertilizer levels using hyperspectral imaging technique. RESULTS: Spectral data were extracted from the region of interest, followed by the first derivative to reduce background noise. Five optimal wavelengths were selected by principal component analysis. Texture features were extracted from the images at optimal wavelengths by gray-level gradient co-occurrence matrix. Support vector machine (SVM) and extreme learning machine were used to build classification models based on spectral data, optimal wavelengths, texture features and data fusion, respectively. The SVM model using fused data gave the best performance with highest correct classification rate of 100% for prediction set. CONCLUSION: The overall results indicated that visible and near-infrared hyperspectral imaging combined with SVM were effective in discriminating N fertilizer levels of tea plants. © 2018 Society of Chemical Industry.


Assuntos
Camellia sinensis/química , Fertilizantes/análise , Nitrogênio/análise , Análise Espectral/métodos , Camellia sinensis/metabolismo , Nitrogênio/metabolismo , Folhas de Planta/química , Folhas de Planta/metabolismo , Análise de Componente Principal , Controle de Qualidade , Análise Espectral/instrumentação , Máquina de Vetores de Suporte
10.
Clin Lab ; 62(1-2): 1-6, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27012027

RESUMO

BACKGROUND: The aim was to develop a better experimental model which could facilitate further studies assessing the vertical HCV gene transmission via human spermatozoa, and verify the possibility of father-to-child transmission of the HCV gene. METHODS: The recombinant plasmid pIRES2-EGFP-HCV C was constructed. Fluorescence in situ hybridization was performed to detect the integration of the HCV C gene in human sperm genome and in zygote's pronucleus. RESULTS: Successful construction of recombinant plasmid pIRES2-EGFP-HCV C was confirmed by restriction mapping, PCR, and sequencing. Positive HCV C DNA signals were observed in sperm heads, human sperm chromosomes and two-cell embryos in transfected samples. No positive signal was found in normal control and HCV infected groups. CONCLUSIONS: The recombinant plasmid pIRES2-EGFP-HCV C was successfully constructed. The HCV C gene was able to pass through the sperm membrane and integrate into the sperm genome. Human sperm carrying the HCV C gene was able to achieve normal fertilization. The replication of the sperm-mediated HCV C gene was synchronized with that of the host genome. Our results provide direct evidence for vertical transmission of the HCV C gene from father-to-child via human sperm.


Assuntos
Hepacivirus/patogenicidade , Hepatite C/transmissão , Transmissão Vertical de Doenças Infecciosas , Espermatozoides/virologia , Zigoto/virologia , Adulto , Animais , Estudos de Casos e Controles , Cromossomos Humanos , Cricetinae , DNA Viral/biossíntese , DNA Viral/genética , Feminino , Fertilização in vitro , Genes Reporter , Proteínas de Fluorescência Verde/biossíntese , Proteínas de Fluorescência Verde/genética , Hepacivirus/genética , Hepacivirus/metabolismo , Humanos , Hibridização in Situ Fluorescente , Masculino , Mesocricetus , Pessoa de Meia-Idade , Integração Viral , Replicação Viral , Adulto Jovem
11.
Clin Lab ; 62(3): 373-9, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27156326

RESUMO

BACKGROUND: To determine the degree of chromosomal aberrations in the sperm of men with hepatitis C. METHODS: 36 subjects (20 in the healthy control group and 16 in the HCV infection group [genotype 1b]) were recruited. The cause of viral transmission was unknown in all patients. Sperm samples from the subjects were used for interspecies in vitro fertilization of zona-free golden hamster ova. The frequencies of spermatozoan aberrations were compared between the healthy control group and the HCV infection group. RESULTS: A total of 280 sperm chromosome complements were studied, including 129 complements from the 16 donors in the HCV infection group and 151 from the healthy control group. Of the 129 analyzable sperm metaphase spreads in the HCV infection group, 14 (10.85%) complements contained chromosomal aberrations, which was significantly higher than the number (9/151, 5.96%) in the healthy control group (p < 0.01). Moreover, in the HCV infection group, chromosomes frequently showed anomalies such as stickiness, clumping, and failure to stain, which prevented their analysis. CONCLUSIONS: HCV infection has mutagenic effects on the chromosomes in sperm and may lead to extensive heredi-tary effects owing to genetic alterations and/or chromosomal aberrations. In addition, there is the possibility of vertical transmission of HCV via the germ line.


Assuntos
Aberrações Cromossômicas , Hepatite C/genética , Espermatozoides/ultraestrutura , Adulto , Humanos , Masculino
12.
BMC Bioinformatics ; 16: 38, 2015 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-25652331

RESUMO

BACKGROUND: Hepatitis B virus (HBV) genotypes have a distinct geographical distribution and influence disease progression and treatment outcomes. The purpose of this study was to investigate the distribution of HBV genotypes in Europe, the impact of mutation of different genotypes on HBV gene abnormalities, the features of CpG islands in each genotype and their potential role in epigenetic regulation. RESULTS: Of 383 HBV isolates from European patients, HBV genotypes A-G were identified, with the most frequent being genotype D (51.96%) in 12 countries, followed by A (39.16%) in 7 countries, and then E (3.66%), G (2.87%), B (1.57%), F (0.52%) and C (0.26%). A higher rate of mutant isolates were identified in those with genotype D (46.7%) followed by G (45.5%), and mutations were associated with structural and functional abnormalities of HBV genes. Conventional CpG island I was observed in genotypes A, B, C, D and E. Conventional islands II and III were detected in all A-G genotypes. A novel CpG island IV was found in genotypes A, D and E, and island V was only observed in genotype F. The A-G genotypes lacked the novel CpG island VI. "Split" CpG island I in genotypes D and E and "split" island II in genotypes A, D, E, F and G were observed. Two mutant isolates from genotype D and one from E were found to lack both CpG islands I and III. CONCLUSIONS: HBV genotypes A-G were identified in European patients. Structural and functional abnormalities of HBV genes were caused by mutations leading to the association of genotypes D and G with increased severity of liver disease. The distribution, length and genetic traits of CpG islands were different between genotypes and their biological and clinical significances warrant further study, which will help us better understand the potential role of CpG islands in epigenetic regulation of the HBV genome.


Assuntos
Ilhas de CpG/genética , Epigênese Genética/genética , Vírus da Hepatite B/genética , Hepatite B/virologia , Mutação/genética , Metilação de DNA , Europa (Continente) , Genoma Viral , Genótipo , Vírus da Hepatite B/isolamento & purificação , Humanos
13.
J Med Virol ; 86(9): 1467-72, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24898681

RESUMO

Studies on the sperm-fertilizing capacity of HIV-seropositive men show conflicting results for reasons that are not yet clear. The aim of this study was to investigate the effects and relationships of some factors such as patient age, CD4(+) cells count, fathering offspring, concomitant sexually transmitted diseases (STD), and receipt of highly active anti-retroviral therapy (HAART) on sperm fertilizing capacity. Semen samples were collected from 33 HIV-seropositive men. Data on the above factors were acquired from a self-designed questionnaire. Computer-assisted sperm analysis, a hypo-osmotic swelling, and zona-free hamster oocyte penetration tests were performed according to criteria of the World Health Organization. CD4(+) cells in peripheral blood were examined using a flow cytometric (FCM) analyzer. Sperm vitality, sperm motility (grades a + b), total sperm motility, and sperm penetration rates were significantly higher in patients whose CD4(+) counts were ≧350/µl than in those whose CD4(+) counts were <350/µl (P < 0.05), and the parameters mentioned above were also significantly correlated with CD4(+) cell number (all P < 0.05). Significant differences in total sperm count and sperm tail swelling rate between patients co-infected with STD and without STD were observed (P < 0.05). Sperm penetration rate in patients receiving HAART was significantly higher than in those not receiving HAART (P < 0.05). Blood CD4(+) cell counts are an important indicator for evaluating sperm fertilizing capacity of HIV-seropositive men. After receiving HAART, the sperm penetration rate of HIV-seropositive men can be improved.


Assuntos
Infecções por HIV/imunologia , Infertilidade Masculina/imunologia , Espermatozoides/fisiologia , Adulto , Animais , Terapia Antirretroviral de Alta Atividade , Contagem de Linfócito CD4 , Cricetinae , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Humanos , Infertilidade Masculina/virologia , Masculino , Pessoa de Meia-Idade , Oócitos/fisiologia , Contagem de Espermatozoides , Motilidade dos Espermatozoides , Interações Espermatozoide-Óvulo , Adulto Jovem
14.
Yi Chuan ; 35(8): 983-91, 2013 Aug.
Artigo em Zh | MEDLINE | ID: mdl-23956086

RESUMO

The genomic and transcriptomic studies have been greatly accelerated by the next-generation sequencing technology. Currently, there are two main methods in transcriptomic studies, namely, Tiling microarray and RNA-seq. Comparatively, because of its overwhelming superiority in transcript coverage and resolution, as well as decrease of costs, RNA-seq has been employed in transcriptome analyses by an increasing number of research institutes. According to the mRNA enrichment or rRNA depletion methods, RNA-seq can be performed in six ways. Among them, dRNA-seq can descriminate the original transcripts from the processed RNAs based on a differential exonuclease treatment. This kind of method has been broadly applied in studies of prokaryotic transcriptional start sites, small regulatory RNAs, promoters and operons, etc. Here, we reviewed the detailed principle and technical process of dRNA-seq and its applications in prokaryotic transcriptome analyses. Besides, we also summarized the advantages and limitations of dRNA-seq at present stage, and then gave our perspective of its future development and potential applications, expecting to present useful references for civil researchers in related fields.


Assuntos
Sequenciamento de Nucleotídeos em Larga Escala , Análise de Sequência de RNA , Perfilação da Expressão Gênica , RNA/genética , Sítio de Iniciação de Transcrição , Transcriptoma
15.
Orthop Surg ; 15(10): 2724-2729, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37382443

RESUMO

BACKGROUND: Limb salvage surgery is the preferred treatment for most malignant bone tumors, but postoperative infection treatment is very challenging. Simultaneously controlling infection and solving bone defects are clinical treatment challenges. CASE PRESENTATION: Here we describe a new technique for treating bone defect infection after bone tumor surgery. An 8-year-old patient suffered an incision infection after osteosarcoma resection and bone defect reconstruction. In response, we designed her a personalized, anatomically matched, antibiotic-loaded, bone cement spacer mold using 3D printing technology. The patient's infection was cured, and limb salvage was successful. In follow-up, the patient had returned to normal postoperative chemotherapy and was able to walk with the help of a cane. There was no obvious pain in the knee joint. At 3 months after operation, the range of motion of the knee joint was 0°-60°. CONCLUSION: The 3D printing spacer mold is an effective solution for treating the infection with large bone defect.


Assuntos
Neoplasias Ósseas , Procedimentos de Cirurgia Plástica , Humanos , Feminino , Criança , Cimentos Ósseos , Articulação do Joelho/cirurgia , Articulação do Joelho/patologia , Neoplasias Ósseas/cirurgia , Neoplasias Ósseas/patologia , Impressão Tridimensional , Resultado do Tratamento
16.
Food Chem ; 427: 136673, 2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-37364316

RESUMO

Traceability and authentication of protected designation of origin (PDO) tea is an important prerequisite to safeguard its production and distribution system. Here, indicator displacement array (IDA) sensors consisting of natural anthocyanidins and edible metal ions were developed to authenticate PDO and non-PDO Longjing from different origins. Five IDA elements were selected for constructing sensors, achieved by an indicator displacement reaction after adding epigallocatechin gallate solution. The obtained sensors were subsequently used for real tea samples. Unsupervised algorithms were used for data exploration among PDO and non-PDO teas. The supervised support vector machine (SVM) model further achieved accurate authentication of PDO and non-PDO Longjing with a correct classification rate of 100% for the 26 validated samples. The developed IDA sensor thus achieves accurate authentication of PDO tea in a hazard-free and cost-efficient way, providing a useful tool for origin authentication of other agricultural products.


Assuntos
Colorimetria , Chá , Análise Custo-Benefício , Antocianinas
17.
Dalton Trans ; 53(1): 245-250, 2023 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-38037871

RESUMO

The electrochemical CO2 reduction reaction (CO2RR) gives an ideal approach for producing valuable chemicals, offering dual benefits in terms of environmental preservation and carbon recycling. In this work, a strong synergistic effect is constructed by adopting electron-rich graphdiyne (GDY) as the supporting matrix, which significantly stabilizes the Au active sites and boosts the CO2RR process. The as-prepared GDY-supported Au nanoparticles (Au/GDY) exhibit excellent CO2RR performance, with an extremely high faradaic efficiency of 94.6% for CO as well as good stability with continuous electrolysis for 36 hours. The superior activity and stability of the Au/GDY catalyst can be attributed to the electronic interaction between Au nanoparticles and the GDY substrate, resulting in enhanced electron transfer rates and a stable network of catalytically active sites that ultimately promote the CO2RR.

18.
Sci Rep ; 12(1): 17473, 2022 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-36261479

RESUMO

In this paper, a novel robust distributed consensus control scheme based on event-triggered adaptive sliding mode control is proposed for multiagent systems with unknown disturbances in a leader-follower framework. First, an adaptive multivariate disturbance observer is utilized to compensate for the disturbance of each agent. Next, a distributed consensus control protocol is constructed via integral sliding mode control, in which a novel adaptive law is designed for the switching gain to overcome the unknown perturbations. An event-triggered strategy is designed to update the control input. Furthermore, the feasibility of the proposed scheme is rigorously analyzed by Lyapunov theory, and a lower bound expression for the inter-event time is derived to guarantee that Zeno behavior can be excluded. The proposed nonlinear consensus algorithm is remarkable in that it does not require any information about the bounds of the disturbances. Finally, compared with existing methods, the proposed algorithm is validated through detailed numerical simulations. In addition, the proposed algorithm is applied to a group of UAVs in this paper, and the results show that it has more application value.

19.
J Agric Food Chem ; 70(1): 136-148, 2022 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-34964344

RESUMO

Flavoalkaloids are a unique class of compounds in tea, most of which have an N-ethyl-2-pyrrolidinone moiety substituted at the A ring of a catechin skeleton. 1-Ethyl-5-hydroxy-pyrrolidone, a decomposed product of theanine, was supposed to be the key intermediate to form tea flavoalkaloids. However, we have also detected another possible theanine intermediate, 1-ethyl-5-oxopyrrolidine-2-carboxylic acid, and speculated if there are related conjugated catechins. Herein, four novel spiro-flavoalkaloids with a spiro-γ-lactone structural moiety were isolated from Yingde green tea (Camellia sinensis var. assamica) in our continuing exploration of new chemical constituents from tea. The structures of the new compounds, spiro-flavoalkaloids A-D (1-4), were further elucidated by extensive nuclear magnetic resonance (NMR) spectroscopy together with the calculated 13C NMR, IR, UV-vis, high-resolution mass, optical rotation, experimental, and calculated circular dichroism spectra. We also provided an alternative pathway to produce these novel spiro-flavoalkaloids. Additionally, their α-glucosidase inhibitory activities were determined with IC50 values of 3.34 (1), 5.47 (2), 22.50 (3), and 15.38 (4) µM. Docking results revealed that compounds 1 and 2 mainly interacted with residues ASP-215, ARG-442, ASP-352, GLU-411, HIS-280, ARG-315, and ASN-415 of α-glucosidase through hydrogen bonds. The fluorescence intensity of α-glucosidase could be quenched by compounds 1 and 2 in a static style.


Assuntos
Alcaloides/farmacologia , Camellia sinensis , Inibidores de Glicosídeo Hidrolases/farmacologia , Chá/química , Camellia sinensis/química , Catequina , alfa-Glucosidases
20.
Fish Shellfish Immunol ; 30(1): 378-88, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21109006

RESUMO

Interleukin-2 enhancer binding factor 2 (ILF2), also named as nuclear factor 45 (NF45), plays important roles in regulating interleukin-2 expression in mammals. In the present study, a novel ILF2 gene (designated EcILF2) was cloned and well characterized from orange-spotted grouper, Epinephelus coioides. The full-length EcILF2 cDNA is composed of 1544 bp and encodes a polypeptide of 387 amino acids with 98% identity to ILF2 of Atlantic salmon. The genomic DNA of EcILF2 consists of 14 exons and 13 introns, with a length of approximately 6.9 kb. EcILF2 contains two conserved domains including an RGG-rich single-stranded RNA-binding domain and a DZF zinc-finger nucleic acid binding domain. Recombinant EcILF2 was expressed in Escherichia coli BL21 (DE3) and purified for mouse anti-EcILF2 serum preparation. Subcellular localization analysis revealed that EcILF2 was distributed predominantly in the nucleus. Realtime quantitative PCR (RT-qPCR) analysis revealed a broad expression of EcILF2, with a relative strong expression in skin, liver, brain, head kidney and spleen. The expression of EcILF2 was differentially up-regulated after stimulation with Vibrio vulnificus, Staphylococcus aureus, Saccharomyces cerevisiae and Singapore grouper iridovirus (SGIV). Furthermore, EcILF2 was able to activate human IL-2 promoter in different cell lines and promote the endogenous IL-2 transcription in human H9 T cells. These results suggest that EcILF2 is potentially involved in grouper immune responses to invasion of bacterial and viral pathogens.


Assuntos
Regulação da Expressão Gênica/fisiologia , Proteína do Fator Nuclear 45/metabolismo , Perciformes/metabolismo , Sequência de Aminoácidos , Animais , Anticorpos , Sequência de Bases , Linhagem Celular , Clonagem Molecular , Infecções por Vírus de DNA/imunologia , Infecções por Vírus de DNA/metabolismo , Infecções por Vírus de DNA/veterinária , Doenças dos Peixes/metabolismo , Doenças dos Peixes/virologia , Perfilação da Expressão Gênica , Iridoviridae , Dados de Sequência Molecular , Proteína do Fator Nuclear 45/genética , Vibrioses
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