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1.
Proc Natl Acad Sci U S A ; 120(20): e2303479120, 2023 05 16.
Artículo en Inglés | MEDLINE | ID: mdl-37155876

RESUMEN

The human tumor suppressor Ring finger protein 20 (RNF20)-mediated histone H2B monoubiquitination (H2Bub) is essential for proper chromosome segregation and DNA repair. However, what is the precise function and mechanism of RNF20-H2Bub in chromosome segregation and how this pathway is activated to preserve genome stability remain unknown. Here, we show that the single-strand DNA-binding factor Replication protein A (RPA) interacts with RNF20 mainly in the S and G2/M phases and recruits RNF20 to mitotic centromeres in a centromeric R-loop-dependent manner. In parallel, RPA recruits RNF20 to chromosomal breaks upon DNA damage. Disruption of the RPA-RNF20 interaction or depletion of RNF20 increases mitotic lagging chromosomes and chromosome bridges and impairs BRCA1 and RAD51 loading and homologous recombination repair, leading to elevated chromosome breaks, genome instability, and sensitivities to DNA-damaging agents. Mechanistically, the RPA-RNF20 pathway promotes local H2Bub, H3K4 dimethylation, and subsequent SNF2H recruitment, ensuring proper Aurora B kinase activation at centromeres and efficient loading of repair proteins at DNA breaks. Thus, the RPA-RNF20-SNF2H cascade plays a broad role in preserving genome stability by coupling H2Bub to chromosome segregation and DNA repair.


Asunto(s)
Reparación del ADN por Recombinación , Proteína de Replicación A , Humanos , Cromatina , Segregación Cromosómica , Reparación del ADN , Inestabilidad Genómica , Histonas/genética , Histonas/metabolismo , Recombinación Homóloga , Proteína de Replicación A/genética , Proteína de Replicación A/metabolismo
2.
Anal Chem ; 96(4): 1789-1794, 2024 01 30.
Artículo en Inglés | MEDLINE | ID: mdl-38230634

RESUMEN

Highly sensitive and facile detection of low levels of protein markers is of great significance for the early diagnosis and efficacy monitoring of diseases. Herein, aided by an efficient tyramine-signal amplification (TSA) mechanism, we wish to report a simple but ultrasensitive immunoassay with signal readout on a portable personal glucose meter (PGM). In this study, the bioconjugates of tyramine and invertase (Tyr-inv), which act as the critical bridge to convert and amplify the protein concentration information into glucose, are prepared following a click chemistry reaction. Then, in the presence of a target protein, the sandwich immunoreaction between the immobilized capture antibody, the target protein, and the horseradish peroxidase (HRP)-conjugated detection antibody is specifically performed in a 96-well microplate. Subsequently, the specifically loaded HRP-conjugated detection antibodies will catalyze the amplified deposition of a large number of Tyr-inv molecules onto adjacent proteins through highly efficient TSA. Then, the deposited invertase, whose dosage can faithfully reflect the original concentration of the target protein, can efficiently convert sucrose to glucose. The amount of finally produced glucose is simply quantified by the PGM, realizing the highly sensitive detection of trace protein markers such as the carcinoembryonic antigen and alpha fetoprotein antigen at the fg/mL level. This method is simple, cost-effective, and ultrasensitive without the requirement of sophisticated instruments or specialized laboratory equipment, which may provide a universal and promising technology for highly sensitive immunoassay for in vitro diagnosis of diseases.


Asunto(s)
Técnicas Biosensibles , Glucosa , beta-Fructofuranosidasa/química , Técnicas Biosensibles/métodos , Inmunoensayo/métodos , Anticuerpos , Peroxidasa de Rábano Silvestre/química , Tiramina/química , Oro/química
3.
Chembiochem ; : e202400261, 2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38819577

RESUMEN

Autophagy is an important biological mechanism for eukaryotic cells to regulate growth, death, and energy metabolism, and plays an important role in removing damaged organelles, misfolded or aggregated proteins, and clearing pathogens. It has been found that autophagy is closely related to cell survival and death, and is of great significance in cancerigenesis and development, playing a bidirectional role in cancer inhibition and cancer promotion. Therefore, treating cancers by regulating autophagy has attracted much attention. A large amount of research evidence indicates that polymeric nanomaterials are able to regulate cellular autophagy, and their good biocompatibility, degradability, and functionalizable modification open up a broad application prospect for improving the therapeutic effect of cancers. This review provides an overview of the research progress of polymeric nanomaterials for modulating autophagy in the treatment of cancers.

4.
Ren Fail ; 46(1): 2354918, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38757723

RESUMEN

Cisplatin is a particularly potent antineoplastic drug. However, its usefulness is restricted due to the induction of nephrotoxicity. More recent research has indicated that ß-hydroxybutyrate (ß-HB) protects against acute or chronic organ damage as an efficient healing agent. Nonetheless, the therapeutic mechanisms of ß-HB in acute kidney damage caused by chemotherapeutic drugs remain unclear. Our study developed a model of cisplatin-induced acute kidney injury (AKI), which involved the administration of a ketogenic diet or ß-HB. We analyzed blood urea nitrogen (BUN) and creatinine (Cr) levels in serum, and used western blotting and immunohistochemical staining to assess ferroptosis and the calcium/calmodulin-dependent kinase kinase 2 (Camkk2)/AMPK pathway. The mitochondrial morphology and function were examined. Additionally, we conducted in vivo and in vitro experiments using selective Camkk2 inhibitor or activator to investigate the protective mechanism of ß-HB on cisplatin-induced AKI. Exogenous or endogenous ß-HB effectively alleviated cisplatin-induced abnormally elevated levels of BUN and Cr and renal tubular necrosis in vivo. Additionally, ß-HB reduced ferroptosis biomarkers and increased the levels of anti-ferroptosis biomarkers in the kidney. ß-HB also improved mitochondrial morphology and function. Moreover, ß-HB significantly attenuated cisplatin-induced cell ferroptosis and damage in vitro. Furthermore, western blotting and immunohistochemical staining indicated that ß-HB may prevent kidney injury by regulating the Camkk2-AMPK pathway. The use of the Camkk2 inhibitor or activator verified the involvement of Camkk2 in the renal protection by ß-HB. This study provided evidence of the protective effects of ß-HB against cisplatin-induced nephrotoxicity and identified inhibited ferroptosis and Camkk2 as potential molecular mechanisms.


ß-HB protects against cisplatin-induced renal damage both in vivo and in vitro.Moreover, ß-HB is effective in attenuating cisplatin-induced lipid peroxidation and ferroptosis.The regulation of energy metabolism, as well as the treatment involving ß-HB, is associated with Camkk2.


Asunto(s)
Ácido 3-Hidroxibutírico , Lesión Renal Aguda , Quinasa de la Proteína Quinasa Dependiente de Calcio-Calmodulina , Cisplatino , Ferroptosis , Cisplatino/efectos adversos , Cisplatino/toxicidad , Animales , Ferroptosis/efectos de los fármacos , Lesión Renal Aguda/inducido químicamente , Lesión Renal Aguda/prevención & control , Lesión Renal Aguda/metabolismo , Lesión Renal Aguda/patología , Quinasa de la Proteína Quinasa Dependiente de Calcio-Calmodulina/metabolismo , Masculino , Ratones , Ácido 3-Hidroxibutírico/farmacología , Modelos Animales de Enfermedad , Riñón/efectos de los fármacos , Riñón/patología , Riñón/metabolismo , Antineoplásicos/toxicidad , Antineoplásicos/efectos adversos , Ratones Endogámicos C57BL , Transducción de Señal/efectos de los fármacos , Proteínas Quinasas Activadas por AMP/metabolismo , Nitrógeno de la Urea Sanguínea , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Creatinina/sangre , Humanos
5.
Molecules ; 29(7)2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38611873

RESUMEN

The performance of nano-zero-valent iron for heavy metal remediation can be enhanced via incorporation into bimetallic carbon composites. However, few economical and green approaches are available for preparing bimetallic composite materials. In this study, novel Co/Fe bimetallic biochar composites (BC@Co/Fe-X, where X = 5 or 10 represents the CoCl2 concentration of 0.05 or 0.1 mol L-1) were prepared for the adsorption of Pb2+. The effect of the concentration of cross-linked metal ions on Pb2+ adsorption was investigated, with the composite prepared using 0.05 mol L-1 Co2+ (BC@Co/Fe-5) exhibiting the highest adsorption performance. Various factors, including the adsorption period, Pb2+ concentration, and pH, affected the adsorption of Pb2+ by BC@Co/Fe-5. Further characterisation of BC@Co/Fe-5 before and after Pb2+ adsorption using methods such as X-ray diffraction and X-ray photoelectron spectroscopy suggested that the Pb2+ adsorption mechanism involved (i) Pb2+ reduction to Pb0 by Co/Fe, (ii) Co/Fe corrosion to generate Fe2+ and fix Pb2+ in the form of PbO, and (iii) Pb2+ adsorption by Co/Fe biochar. Notably, BC@Co/Fe-5 exhibited excellent remediation performance in simulated Pb2+-contaminated water and soil with good recyclability.

6.
Biol Reprod ; 109(5): 570-585, 2023 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-37669135

RESUMEN

The Fanconi anemia pathway is a key pathway involved in the repair of deoxyribonucleic acidinterstrand crosslinking damage, which chiefly includes the following four modules: lesion recognition, Fanconi anemia core complex recruitment, FANCD2-FANCI complex monoubiquitination, and downstream events (nucleolytic incision, translesion synthesis, and homologous recombination). Mutations or deletions of multiple Fanconi anemia genes in this pathway can damage the interstrand crosslinking repair pathway and disrupt primordial germ cell development and oocyte meiosis, thereby leading to abnormal follicular development. Premature ovarian insufficiency is a gynecological clinical syndrome characterized by amenorrhea and decreased fertility due to decreased oocyte pool, accelerated follicle atresia, and loss of ovarian function in women <40 years old. Furthermore, in recent years, several studies have detected mutations in the Fanconi anemia gene in patients with premature ovarian insufficiency. In addition, some patients with Fanconi anemia exhibit symptoms of premature ovarian insufficiency and infertility. The Fanconi anemia pathway and premature ovarian insufficiency are closely associated.


Asunto(s)
Anemia de Fanconi , Humanos , Femenino , Adulto , Anemia de Fanconi/complicaciones , Anemia de Fanconi/genética , Anemia de Fanconi/metabolismo , Reparación del ADN/genética , Replicación del ADN , Ubiquitinación , Mutación , Daño del ADN
7.
J Vasc Res ; 60(4): 234-244, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37643584

RESUMEN

INTRODUCTION: Culturing cerebrovascular smooth muscle cells (CVSMCs) in vitro can provide a model for studying many cerebrovascular diseases. This study describes a convenient and efficient method to obtain mouse CVSMCs by enzyme digestion. METHODS: Mouse circle of Willis was isolated, digested, and cultured with platelet-derived growth factor-BB (PDGF-BB) to promote CVSMC growth, and CVSMCs were identified by morphology, immunofluorescence analysis, and flow cytometry. The effect of PDGF-BB on vascular smooth muscle cell (VSMC) proliferation was evaluated by cell counting kit (CCK)-8 assay, morphological observations, Western blotting, and flow cytometry. RESULTS: CVSMCs cultured in a PDGF-BB-free culture medium had a typical peak-to-valley growth pattern after approximately 14 days. Immunofluorescence staining and flow cytometry detected strong positive expression of the cell type-specific markers alpha-smooth muscle actin (α-SMA), smooth muscle myosin heavy chain 11 (SMMHC), smooth muscle protein 22 (SM22), calponin, and desmin. In the CCK-8 assay and Western blotting, cells incubated with PDGF-BB had significantly enhanced proliferation compared to those without PDGF-BB. CONCLUSION: We obtained highly purified VSMCs from the mouse circle of Willis using simple methods, providing experimental materials for studying the pathogenesis and treatment of neurovascular diseases in vitro. Moreover, the experimental efficiency improved with PDGF-BB, shortening the cell cultivation period.


Asunto(s)
Círculo Arterial Cerebral , Músculo Liso Vascular , Animales , Ratones , Becaplermina/farmacología , Becaplermina/metabolismo , Proteínas Proto-Oncogénicas c-sis/farmacología , Proteínas Proto-Oncogénicas c-sis/metabolismo , Músculo Liso Vascular/metabolismo , Células Cultivadas , Proliferación Celular , Miocitos del Músculo Liso/metabolismo , Movimiento Celular
8.
Ann Hematol ; 102(3): 529-539, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36680600

RESUMEN

Aplastic anemia (AA) is an auto-activated T cell-mediated bone marrow failure. Cyclosporine is often used to treat non-severe AA, which demonstrates a more heterogeneous condition than severe AA. The response rate to cyclosporine is only around 50% in non-severe AA. To better predict response to cyclosporine and pinpoint who is the appropriate candidate for cyclosporine, we performed phenotypic and functional T cell immune signature at single cell level by mass cytometry from 30 patients with non-severe AA. Unexpectedly, non-significant differences of T cell subsets were observed between AA and healthy control or cyclosporine-responder and non-responders. Interestingly, when screening the expression of co-inhibitory molecules, T cell trafficking mediators, and cytokines, we found an increase of cytotoxic T lymphocyte antigen 4 (CTLA-4) on T cells in response to cyclosporine and a lower level of CTLA-4 on CD8+ T cells was correlated to hematologic response. Moreover, a decreased expression of sphingosine-1-phosphate receptor 1 (S1P1) on naive T cells and a lower level of interleukin-9 (IL-9) on T helpers also predicted a better response to cyclosporine, respectively. Therefore, the T cell immune signature, especially in CTAL-4, S1P1, and IL-9, has a predictive value for response to cyclosporine. Collectively, our study implies that immune signature analysis of T cell by mass cytometry is a useful tool to make a strategic decision on cyclosporine treatment of AA.


Asunto(s)
Anemia Aplásica , Linfocitos T , Humanos , Anemia Aplásica/diagnóstico , Linfocitos T CD8-positivos/metabolismo , Antígeno CTLA-4/metabolismo , Ciclosporina , Interleucina-9/metabolismo , Linfocitos T/inmunología
9.
Qual Life Res ; 32(4): 1119-1131, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36652183

RESUMEN

PURPOSE: Health-related quality of life (HRQoL) is a multi-dimensional construct used to assess the impact of health status on quality of life, and it is known to be affected by lifestyle behaviors. This study focused on multiple lifestyle behaviors among patients with hematologic diseases, including physical activity, dietary intake, sleep quality, occupational exposure, alcohol consumption and smoking. The main objective was to investigate the association of both individual and clustering of health behaviors with HRQoL among the population with hematologic diseases based on a comprehensive lifestyle survey. METHODS: A total of 539 patients with hematologic diseases aged over 18 years were enrolled in this cross-sectional study. Latent class analysis was used to identify homogeneous, mutually exclusive lifestyle classes, and multinomial logistic regression was then performed to explore the association of lifestyle classes membership with HRQoL. Meanwhile, multiple linear regression and quantile regression were used to identify the relationship between individual lifestyle behaviors and HRQoL. RESULTS: A three-class model was selected based on conceptual interpretation and model fit. We found no association between multiple lifestyle behaviors and HRQoL in the 3-class model, either in the whole patients or in subgroups stratified by hematological malignancies. Further research on each lifestyle found that physical activity, dietary intake, occupational exposure, alcohol consumption or smoking were independent of HRQoL. Sleep quality was positively associated with HRQoL. CONCLUSION: Our findings suggested that clustering of lifestyle behaviors may not be an indicator to reflect the health quality of patients with hematologic diseases. Sleep represents a viable intervention target that can confer health benefits on the hematologic patients.


Asunto(s)
Enfermedades Hematológicas , Calidad de Vida , Humanos , Adulto , Persona de Mediana Edad , Calidad de Vida/psicología , Estudios Transversales , Estilo de Vida , Conductas Relacionadas con la Salud , Encuestas y Cuestionarios
10.
Int J Mol Sci ; 24(13)2023 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-37446278

RESUMEN

Many organisms can sense and respond to magnetic fields (MFs), with migratory species in particular utilizing geomagnetic field information for long-distance migration. Cryptochrome proteins (Crys) along with a highly conserved Iron-sulfur cluster assembly protein (i.e., MagR) have garnered significant attention for their involvement in magnetoresponse (including magnetoreception). However, in vivo investigations of potential transcriptional crosstalk between Crys and MagR genes have been limited. The brown planthopper, Nilaparvata lugens, is a major migratory pest insect and an emerging model for studying MF intensity-related magnetoresponse. Here, we explored in vivo transcriptional crosstalk between Crys (Cry1 and Cry2) and MagR in N. lugens. The expression of Crys and MagR were found to be sensitive to MF intensity changes as small as several micro-teslas. Knocking down MagR expression led to a significant downregulation of Cry1, but not Cry2. The knockdown of either Cry1 or Cry2 individually did not significantly affect MagR expression. However, their double knockdown resulted in significant upregulation of MagR. Our findings clearly indicate transcriptional crosstalk between MagR and Crys known to be involved in magnetoresponse. This work advances the understanding of magnetoresponse signaling and represents a key initial step towards elucidating the functional consequences of these novel in vivo interactions.


Asunto(s)
Criptocromos , Hemípteros , Animales , Criptocromos/genética , Criptocromos/metabolismo , Hemípteros/metabolismo , Transducción de Señal , Azufre/metabolismo , Hierro/metabolismo
11.
Bull Environ Contam Toxicol ; 109(3): 477-483, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35849168

RESUMEN

In order to remediate the phytotoxicity of quinclorac to tomato by multi-walled carbon nanotubes (MWCNTs), the adsorption of quinclorac to MWCNTs was monitored and the effect of MWCNTs on the phytotoxicity of quinclorac to tomato in soil were studied. The results showed that the Linear equation and Freundlich equation can well fit the adsorption isotherm of quinclorac in the soil containing MWCNTs. The adsorption of quinclorac in soil was significantly enhanced by the addition of MWCNTs; the Kd of soil (1% MWCNTs) was 28.7 times of pure soil. The quinclorac had an obvious inhibitory effect on the growth of tomatoes; serious phytotoxicity was also induced even at the lowest concentration of 0.025 mg/kg. With the MWCNTs content in soil increased to 0.5% and 1%, the phytotoxicity of quinclorac to tomatoes decreased significantly, and the height and fresh weight of tomatoes were even higher than those of the control group, indicating that MWCNTs can promote the growth of tomato. These results provide a reference for resolving the problem of phytotoxicity induced by residual herbicides in farmland.


Asunto(s)
Nanotubos de Carbono , Solanum lycopersicum , Adsorción , Nanotubos de Carbono/toxicidad , Quinolinas , Suelo
12.
Blood Cells Mol Dis ; 89: 102573, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33957358

RESUMEN

Pure red cell aplasia (PRCA) is a rare syndrome characterized by severe anemia and absence of erythroid precursors. PRCA associated to monoclonal gammopathy of undetermined significance (MGUS) is a scarce condition with less than five cases reported so far. There is no agreement on the treatment of MGUS associated PRCA and treatment- free survival (TFS) is an unmet clinical need. In this report, for the first time, we demonstrated two patients with MGUS associated PRCA obtained rapid remission and maintained TFS after accepting intensive short-term bortezomib plus dexamethasone. The first case was refractory to cyclosporine and prednisone, but achieved complete remission after ten doses of bortezomib. Moreover, he has kept TFS for 12 months. The other case initiated bortezomib plus dexamethasone as soon as making a definite diagnosis. She obtained complete remission after twelve doses of bortezomib and she has maintained a normal level of haemoglobin for 8 months.


Asunto(s)
Antineoplásicos/uso terapéutico , Bortezomib/uso terapéutico , Dexametasona/uso terapéutico , Gammopatía Monoclonal de Relevancia Indeterminada/complicaciones , Aplasia Pura de Células Rojas/tratamiento farmacológico , Aplasia Pura de Células Rojas/etiología , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Análisis de Supervivencia
13.
Sensors (Basel) ; 21(13)2021 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-34203508

RESUMEN

The influence of earthquake disasters on human social life is positively related to the magnitude and intensity of the earthquake, and effectively avoiding casualties and property losses can be attributed to the accurate prediction of earthquakes. In this study, an electromagnetic sensor is investigated to assess earthquakes in advance by collecting earthquake signals. At present, the mainstream earthquake magnitude prediction comprises two methods. On the one hand, most geophysicists or data analysis experts extract a series of basic features from earthquake precursor signals for seismic classification. On the other hand, the obtained data related to earth activities by seismograph or space satellite are directly used in classification networks. This article proposes a CNN and designs a 3D feature-map which can be used to solve the problem of earthquake magnitude classification by combining the advantages of shallow features and high-dimensional information. In addition, noise simulation technology and SMOTE oversampling technology are applied to overcome the problem of seismic data imbalance. The signals collected by electromagnetic sensors are used to evaluate the method proposed in this article. The results show that the method proposed in this paper can classify earthquake magnitudes well.


Asunto(s)
Aprendizaje Profundo , Desastres , Terremotos , Simulación por Computador , Fenómenos Electromagnéticos , Humanos
14.
BMC Med Genet ; 21(1): 88, 2020 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-32357928

RESUMEN

BACKGROUND: Interleukin (IL) 28B polymorphisms encoding pro-inflammatory and anti-inflammatory cytokines trigger diverse clinical outcome of hepatitis virus infection. However, there is controversy concerning the association of IL28B polymorphisms with the outcome of hepatitis B virus (HBV) infection, with several studies obtaining inconsistent results. We performed a meta-analysis to evaluate the role of 3 single nucleotide polymorphisms (SNPs) rs12979860, rs12980275 and rs8099917 in the progression of HBV infection, overall and by ethnicity. METHODS: Searched PubMed, Embase and Wiley Online Library electronic databases using 'interleukin 28B', 'IL 28B', 'IL 28B polymorphism', 'hepatitis B virus', 'HBV', and performed meta- analysis for rs12979860, rs12980275 and rs8099917 in Asian and Caucasian populations under the dominant recessive and allele model. RESULTS: Eighteen studies were found in total and used for this meta-analysis, including 5587 cases and 4295 controls. The IL28B polymorphism rs12979860 had no association with HBV persistence (CC vs CT + TT: OR = 0.86, 95% CI = 0.76-1.00; TT vs CT + CC: OR = 1.14, 95% CI = 0.76-1.70; T vs C: OR = 1.03, 95% CI = 0.94-1.13). Similarly, neither rs12980275 nor rs8099917 had associations with HBV persistence (rs12980275 in AA vs AG + AA: OR = 1.15, 95% CI = 0.96-1.38; rs8099917 in TT vs GT + GG: OR = 1.15, 95% CI = 0.96-1.39). There was also no significant association of IL28B polymorphisms with persistent HBV infection in Asians or Chinese. There was no evidence of an association of rs12979860 with the HBV-related hepatocellular carcinoma susceptibility (T vs C: OR = 1.53, 95% CI = 0.96-2.43). CONCLUSION: IL28B polymorphisms had no association with the outcome of HBV infection overall, nor in the Asians and the Chinese. These 3 SNPs might not be relevant to the development of HBV infection.


Asunto(s)
Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Hepatitis B/genética , Interferones/genética , Pueblo Asiatico/genética , Femenino , Genotipo , Hepatitis B/patología , Hepatitis B/virología , Virus de la Hepatitis B/patogenicidad , Humanos , Interleucinas/genética , Masculino , Polimorfismo de Nucleótido Simple/genética
15.
FEMS Yeast Res ; 20(3)2020 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-32391887

RESUMEN

Cryptococcus neoformans is an important invasive fungal pathogen that causes life-threatening meningoencephalitis in humans. Its biological and pathogenic regulatory mechanisms remain largely unknown, particularly due to the presence of those core transcription factors (TFs). Here, we conducted a detailed characterization of the TF Liv4 in the biology and virulence of C. neoformans. Deletion of TF Liv4 protein resulted in growth defect under both normal and stress conditions (such as high temperature and cell wall/membrane damaging agents), drastic morphological damage and also attenuated virulence in C. neoformans. These phenotypic changes might be contributed to transcriptional abnormality in the liv4Δ mutant, in which several cryptococcal genes involved in energy metabolism and cell wall integrity were downregulated. Furthermore, ChIP-seq and ChIP-qPCR assays suggested TF Liv4 might exert its regulatory function in transcription by its activation of RBP1 in C. neoformans. Taken together, our work highlights the importance of TF Liv4 in the growth and virulence of C. neoformans, and it facilitates a better understanding of cryptococcal pathogenesis mechanisms.


Asunto(s)
Cryptococcus neoformans/crecimiento & desarrollo , Cryptococcus neoformans/genética , Proteínas Fúngicas/genética , Regulación Fúngica de la Expresión Génica , Factores de Transcripción/genética , Animales , Criptococosis/microbiología , Cryptococcus neoformans/patogenicidad , Femenino , Proteínas Fúngicas/metabolismo , Perfilación de la Expresión Génica , Macrófagos/microbiología , Ratones , Ratones Endogámicos BALB C , Fenotipo , Factores de Transcripción/metabolismo , Virulencia , Factores de Virulencia/genética
18.
J Nanosci Nanotechnol ; 18(12): 8169-8177, 2018 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-30189934

RESUMEN

The actual casting filling process can be deemed as the coupled flow of air, molten metal and solid-phase particles (such as slag) inside the cavity, which may cause air entrapment, slag inclusion and other casting defects, and affect the quality of casting. Through computation simulation of the casting filling process on the basis of smoothed particle hydrodynamics (SPH) method, it can not only precisely track the motion trajectories of air, molten metal and slag particles, but also precisely predict air entrapment, slag inclusion and other casting defects. This paper established a mathematical model of gas-liquid-solid three-phase flow for the SPH-based casting filling process. The model eliminated the instability of gas-liquid interface pressure by introducing the corrected gas-liquid two-phase momentum equation, and maintained a clear interface between air and molten metal by introducing the surface tension model. In addition, it introduced the motion model of rigid body to deal with the coupled flow process of slag, air and molten metal. The mathematical model established in this paper was used to calculate the bubble floating and the flowing process of the gas-liquid two-phase during mold filling through the bottom side of the injection cavity and of the gas-liquid-solid three-phase flow during mold filling for casting of plate (the plate was composite reinforced with nano SiC, and the viscosity of the composite melt was calculated from the viscosity formula of the composite melt). The calculated results were compared with the experimental results to verify the accuracy and validity of the mathematical model established.

19.
Exp Appl Acarol ; 73(2): 159-176, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29116474

RESUMEN

Tetranychus urticae Koch is a worldwide agricultural pest. There are two color forms: red and green. The molecular mechanism underlying this color variation is unknown. To elucidate the mechanism, we characterized differentially expressed pigment pathway genes shared in the transcriptomes of these two forms using RNA sequencing and reciprocal best hit analysis. Differentially expressed pigment pathway genes were determined by qRT-PCR to confirm the accuracy of RNA-Seq. The transcriptomes revealed 963 differentially expressed genes (DEGs), of which 687 DEGs were higher in the green form. KEGG enrichment analysis revealed carotenoid biosynthesis genes in T. urticae. Reciprocal best hit analysis revealed 817 putative pigment pathway genes, 38 of which were differentially expressed and mainly classified into four categories: heme, melanin, ommochrome and rhodopsin. Phylogenetic analysis of homologous ommochrome genes showed that tetur09g01950 is closely related to Ok. This study revealed putative pigment pathway genes in the two forms of T. urticae, and might provide a new resource for understanding the mechanism of color variation.


Asunto(s)
Proteínas de Artrópodos/genética , Pigmentos Biológicos/genética , Tetranychidae/genética , Transcriptoma , Animales , Proteínas de Artrópodos/metabolismo , Femenino , Fenotiazinas/metabolismo , Filogenia , Pigmentos Biológicos/metabolismo , Análisis de Secuencia de ARN
20.
Yao Xue Xue Bao ; 51(6): 898-906, 2016 06.
Artículo en Zh | MEDLINE | ID: mdl-29879342

RESUMEN

The aim of this study is to investigate the protective effects of Panax notoginseng saponins (PNS) against 6-hydroxydopamine(6-OHDA)-induced apoptosis in SH-SY5Y cells and the possible underlying mechanisms. Cell viability was examined by MTT assay. The levels of lactate dehydrogenase(LDH), reactive oxygen species (ROS), malondialdehyde (MDA) and the activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase(GSH-Px) were measured using the respective assay kits. Apoptosis was measured by TUNEL kit, JC-1 and ROS was measured by staining with fluorescent dyes. The activation of caspase-3 was measured with the caspase-3 assay kit. The expression of nuclear protein Nrf2 and HO-1 were determined by Western blot. PNS had significant protective effects against 6-OHDA-induced apoptosis in SH-SY5Y cells in a time- and dose-dependent manner. PNS could attenuate 6-OHDA-induced suppression of SOD, GAT, GSH-Px (P < 0.01). PNS reduced the level of LDH, decreased the levels of ROS, MDA and increased cell viability and the mitochondrial membrane potential (P < 0.01). PNS also inhibited DNA fragmentation, mitochondrial response and the activation of caspase-3 (P < 0.01). Moreover, PNS pretreatment increased the expression of the nuclear Nrf2 and up-regulate HO-1. The protective effects of PNS could be inhibited by HO-1 inhibitor SnPP. In conclusion, PNS has significant protective effects against 6-OHDA- induced apoptosis in SH-SY5Y cells. The possible mechanisms of PNS are due to PNS-mediated activation of Nrf2, up-regulation of HO-1 and inhibition of oxidative stress.


Asunto(s)
Apoptosis , Panax notoginseng/química , Saponinas/farmacología , Caspasa 3/metabolismo , Línea Celular Tumoral , Supervivencia Celular , Glutatión Peroxidasa/metabolismo , Humanos , Malondialdehído/metabolismo , Potencial de la Membrana Mitocondrial , Estrés Oxidativo , Oxidopamina , Especies Reactivas de Oxígeno/metabolismo , Superóxido Dismutasa/metabolismo
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