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1.
Plant Cell ; 34(3): 1038-1053, 2022 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-34919720

RESUMO

Starch is the main energy storage carbohydrate in plants and serves as an essential carbon storage molecule for plant metabolism and growth under changing environmental conditions. The TARGET of RAPAMYCIN (TOR) kinase is an evolutionarily conserved master regulator that integrates energy, nutrient, hormone, and stress signaling to regulate growth in all eukaryotes. Here, we demonstrate that TOR promotes guard cell starch degradation and induces stomatal opening in Arabidopsis thaliana. Starvation caused by plants growing under short photoperiod or low light photon irradiance, as well as inactivation of TOR, impaired guard cell starch degradation and stomatal opening. Sugar and TOR induce the accumulation of ß-AMYLASE1 (BAM1), which is responsible for starch degradation in guard cells. The plant steroid hormone brassinosteroid and transcription factor BRASSINAZOLE-RESISTANT1 play crucial roles in sugar-promoted expression of BAM1. Furthermore, sugar supply induced BAM1 accumulation, but TOR inactivation led to BAM1 degradation, and the effects of TOR inactivation on BAM1 degradation were abolished by the inhibition of autophagy and proteasome pathways or by phospho-mimicking mutation of BAM1 at serine-31. Such regulation of BAM1 activity by sugar-TOR signaling allows carbon availability to regulate guard cell starch metabolism and stomatal movement, ensuring optimal photosynthesis efficiency of plants.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Carbono/metabolismo , Hormônios/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Serina-Treonina Quinases/genética , Sirolimo , Amido/metabolismo , Açúcares/metabolismo
2.
Nano Lett ; 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38767889

RESUMO

Tumor immunotherapy has emerged as an efficacious therapeutic approach that mobilizes the patient's immune system to achieve durable tumor suppression. Here, we design a photodynamic therapy-motivated nanovaccine (Dex-HDL/ALA-Fe3O4) co-delivering 5-aminolevulinic acid and Fe3O4 nanozyme that demonstrate a long-term durable immunotherapy strategy. After vaccination, the nanovaccine exhibits obvious tumor site accumulation, lymph node homing, and specific and memory antitumor immunity evocation. Upon laser irradiation, Dex-HDL/ALA-Fe3O4 effectively generates reactive oxygen species at the tumor site not only to induce the immunogenic cell death-cascade but also to trigger the on-demand release of full types of tumor antigens. Intriguingly, Fe3O4 nanozyme-catalyzed hydrogen peroxide generated oxygen for alleviating tumor hypoxia and modifying the inhibitory tumor microenvironment, thereby exhibiting remarkable potential as a sensitizer. The intravenous administration of nanovaccines in diverse preclinical cancer models has demonstrated remarkable tumor regression and inhibition of postoperative tumor recurrence and metastasis, thereby enabling personalized treatment strategies against highly heterogeneous tumors.

3.
Toxicol Appl Pharmacol ; 489: 117006, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38880189

RESUMO

Esophageal squamous cell carcinoma (ESCC) is one of the most fatal cancers worldwide. Most ESCC patients are diagnosed at an advanced stage; however, current research on in vivo animal models accurately reflecting their clinical presentation is lacking. Alcohol consumption is a major risk factor for ESCC and has been used in several disease models for disease induction. In this study, we used 4-nitroquinoline-1-oxide in combination with ethanol to induce an in vivo ESCC mouse model. Esophageal tissues were stained with hematoxylin and eosin for histopathological examination and lesion scoring. In cellular experiments, cell adhesion and migration invasion ability were observed using phalloidin staining, cell scratch and transwell assays, respectively, and the expression of epithelial-mesenchymal transition-related markers was detected using quantitative reverse transcription polymerase chain reaction and western blotting. The results showed that ethanol-exposed mice lost more weight and had an increased number of esophageal nodules. Histological examination revealed that the lesion scores of the ethanol-exposed esophageal samples were significantly higher than those of the unexposed esophageal samples. Furthermore, ethanol-exposed esophageal cancer samples had more severe lesions with infiltration of tumor cells into the muscularis propria. In vitro cellular experiments showed that ethanol exposure induced cytoskeletal microfilament formation, promoted cell migration invasion elevated the expression of N-cadherin and Snail, and decreased the expression of E-cadherin. In conclusion, ethanol exposure exacerbates ESCC, promotes tumor cell infiltration into the muscularis propria, and could be an effective agent for establishing innovative models of invasive carcinoma.

4.
Plant Cell ; 32(4): 984-999, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32051210

RESUMO

Starch is the major storage carbohydrate in plants and functions in buffering carbon and energy availability for plant fitness with challenging environmental conditions. The timing and extent of starch degradation appear to be determined by diverse hormonal and environmental signals; however, our understanding of the regulation of starch metabolism is fragmentary. Here, we demonstrate that the phytohormone brassinosteroid (BR) and redox signal hydrogen peroxide (H2O2) induce the breakdown of starch in guard cells, which promotes stomatal opening. The BR-insensitive mutant bri1-116 accumulated high levels of starch in guard cells, impairing stomatal opening in response to light. The gain-of-function mutant bzr1-1D suppressed the starch excess phenotype of bri1-116, thereby promoting stomatal opening. BRASSINAZOLE-RESISTANT1 (BZR1) interacts with the basic leucine zipper transcription factor G-BOX BINDING FACTOR2 (GBF2) to promote the expression of ß-AMYLASE1 (BAM1), which is responsible for starch degradation in guard cells. H2O2 induces BZR1 oxidation, enhancing the interaction between BZR1 and GBF2 to increase BAM1 transcription. Mutations in BAM1 lead to starch accumulation and reduce the effects of BR and H2O2 on stomatal opening. Overall, this study uncovers the critical roles of BR and H2O2 in regulating guard cell starch metabolism and stomatal opening.


Assuntos
Brassinosteroides/farmacologia , Peróxido de Hidrogênio/farmacologia , Estômatos de Plantas/citologia , Estômatos de Plantas/fisiologia , Amido/metabolismo , Arabidopsis/efeitos dos fármacos , Arabidopsis/genética , Arabidopsis/fisiologia , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Modelos Biológicos , Mutação/genética , Estômatos de Plantas/efeitos dos fármacos
5.
Anal Biochem ; 660: 114971, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36328214

RESUMO

Exosome is an emerging tumor marker, whose concentration level can reflect the occurrence and development of tumors. The development of rapid and sensitive exosome detection platform is of great significance for early warning of cancer occurrence. Here, a strategy for electrochemical detection of A549-cell-derived exosomes was established based on DNA/ferrocene-modified single-walled carbon nanotube complex (DNA/SWCNT-Fc). DNA/SWCNT-Fc complexes function as a signal amplification platform to promote electron transfer between electrochemical signal molecules and electrodes, thereby improving sensitivity. At the same time, the exosomes can be attached to DNA/SWCNT-Fc nanocomposites via the established PO43--Ti4+-PO43- method. Moreover, the application of EGFR antibody, which can specifically capture A549 exosomes, could improve the accuracy of this sensing system. Under optimal experimental conditions, the biosensor showed good linear relationship between the peak current and the logarithm of exosomes concentration from 4.66 × 106 to 9.32 × 109 exosomes/mL with a detection limit of 9.38 × 104 exosomes/mL. Furthermore, this strategy provides high selectivity for exosomes of different cancer cells, which can be applied to the detection of exosomes in serum samples. Thus, owing to its advantages of high sensitivity and good selectivity, this method provides a diversified platform for exosomes identification and has great potential in early diagnosis and biomedical applications.


Assuntos
Exossomos , Nanotubos de Carbono , Metalocenos , DNA
6.
J Environ Sci (China) ; 134: 34-43, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37673531

RESUMO

Herein, the coating of MnO2 nanomaterials on the surface of aluminum honeycomb was carried out to meet the requirements of high air velocity, low pressure drop and high activity in ozone removal scenarios. A commercially readily available waterborne silica sol mixed with waterborne acrylate latex was creatively utilized as the binder. A series of coating samples were prepared by spray coating method and evaluated focusing on their adhesion strength and catalytic activity towards ozone decomposition in an air duct at room temperature, by varying MnO2/binder mass ratio and number of sprayings. It was found that the adhesion strength of the catalytic coatings on the aluminum honeycomb increased with the increase of binder mass ratio, but the increased binder made the catalyst particles closely packed, resulting in reduced exposure of active sites and decrease of ozone conversion. Accordingly, catalyst slurry with 81.8 wt.% MnO2 in dry coating and spraying times of two were determined as the optimal process parameters. As-prepared aluminum honeycomb filter with MnO2 layer of 50 µm thickness achieved ozone conversion of 29.3%±1.7% under conditions of air velocity 3.0 m/sec, relative humidity ∼50%, room temperature (26°C) and initial ozone concentration of 200 ppbV. This filter can be well adaptable to indoor air purification equipment operating at high air velocity with low wind resistance.


Assuntos
Alumínio , Ozônio , Compostos de Manganês , Óxidos , Temperatura
7.
Plant Cell Environ ; 45(12): 3551-3565, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36123951

RESUMO

The co-chaperone heat shock protein (HSP)70-HSP90 organizing protein (HOP) is involved in plant thermotolerance. However, its function in plant salinity tolerance was not yet studied. We found that Arabidopsis HOP1 and HOP2 play critical roles in salt tolerance by affecting the nucleo-cytoplasmic partitioning of HSP90 and brassinosteroid-insensitive 2 (BIN2). A hop1/2 double mutant was hypersensitive to salt-stress. Interestingly, this sensitivity was remedied by exogenous brassinolide application, while the application of brassinazole impeded growth of both wild-type (WT) and hop1/2 plants under normal and salt stress conditions. This suggested that the insufficient brassinosteroid (BR) content was responsible for the salt-sensitivity of hop1/2. After WT was transferred to salt stress conditions, HOP1/2, BIN2 and HSP90 accumulated in the nucleus, brassinazole-resistant 1 (BZR1) was phosphorylated and accumulated in the cytoplasm, and BR content significantly increased. This initial response resulted in dephosphorylation of BZR1 and BR response. This dynamic regulation of BR content was impeded in salt-stressed hop1/2. Thus, we propose that HOP1 and HOP2 are involved in salt tolerance by affecting BR signalling.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Brassinosteroides/metabolismo , Proteínas de Arabidopsis/metabolismo , Tolerância ao Sal , Regulação da Expressão Gênica de Plantas , Fosforilação , Arabidopsis/metabolismo , Proteínas de Choque Térmico HSP90/metabolismo , Núcleo Celular/metabolismo , Proteínas Quinases/metabolismo
8.
Anal Bioanal Chem ; 412(17): 4155-4163, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32306069

RESUMO

In this work, a new method of CYFRA21-1 DNA (tDNA) detection based on electrochemically mediated atom transfer radical polymerization (e-ATRP) and surface-initiated reversible addition-fragmentation chain transfer polymerization (SI-RAFT) cascade polymerization and AgNP deposition is proposed. Firstly, the peptide nucleic acid (PNA) probe is captured on a gold electrode by Au-S bonds for specific recognition of tDNA. After hybridization, PNA/DNA strands provide high-density phosphate groups for the subsequent ATRP initiator by the identified carboxylate-Zr4+-phosphate chemistry. Then, a large number of monomers are successfully grafted from the DNA through the e-ATRP reaction. After that, the chain transfer agent of SI-RAFT and methacrylic acid (MAA) are connected by recognized carboxylate-Zr4+-carboxylate chemistry. Subsequently, through SI-RAFT, the resulting polymer introduces numerous aldehyde groups, which could deposit many AgNPs on tDNA through silver mirror reaction, causing significant amplification of the electrochemical signal. Under optimal conditions, this designed method exhibits a low detection limit of 0.487 aM. Moreover, the method enables us to detect DNA at the level of PCR-like and shows high selectivity and strong anti-interference ability in the presence of serum. It suggests that this new sensing signal amplification technology exhibits excellent potential of application in the early diagnosis of non-small cell lung cancer (NSCLC). Graphical abstract Electrochemical detection principle for CYFRA21-1 DNA based on e-ATRP and SI-RAFT signal amplification technology.


Assuntos
Antígenos de Neoplasias/genética , Técnicas Biossensoriais/métodos , DNA/sangue , Queratina-19/genética , Nanopartículas Metálicas/química , Ácidos Nucleicos Peptídicos/química , Prata/química , Carcinoma Pulmonar de Células não Pequenas/sangue , Carcinoma Pulmonar de Células não Pequenas/genética , DNA/genética , Técnicas Eletroquímicas/métodos , Eletrodos , Ouro/química , Humanos , Neoplasias Pulmonares/sangue , Neoplasias Pulmonares/genética , Hibridização de Ácido Nucleico , Ácidos Nucleicos Peptídicos/genética , Polimerização
9.
Biomacromolecules ; 20(9): 3399-3407, 2019 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-31339699

RESUMO

Because of the difference in osmotic pressure, most tough hydrogels swell under physiological conditions, which seriously weakens their mechanical properties, limiting their applications in biomedicine. Herein, a novel strategy based on strong and high-density micelle cross-linkings is proposed to prepare nonswellable and tough hydrogel. To realize a strong micelle cross-linker, the synergetic effect of hydrophobic and quadruple hydrogen-bonding interactions is employed by introducing an alkyl chain-protected ureido pyrimidinone moiety into a segmented copolymer backbone. The length of the alkyl is the key factor in determining the strength of the hydrophobic interaction, which was carefully tailored to gain micelles with high strength and suitable solubility. A supramolecular hydrogel was formed in situ by simply linking micelle cross-linkers with poly(ethylene glycol) chains. The strong and high-density micelle cross-linkings restrain multiple effective chains outside the micelle from stretching during swelling, and the deformability of micelle cross-linkings disperses the local stress to maintain the network with high cross-linking density upon loading. Therefore, the hydrogel exhibited an outstanding nonswelling behavior under physiological conditions and excellent mechanical properties with a compressive strength of 4 MPa. The rapid in situ gelation also facilitated injection and cell encapsulation. Meanwhile, it also showed good tissue adhesion, cytocompatibility, and suitable degradability. This novel and facile strategy can offer new insights into the exploitation of cross-linkings to prepare nonswellable hydrogels for biomedical applications.


Assuntos
Hidrogéis/química , Interações Hidrofóbicas e Hidrofílicas/efeitos dos fármacos , Polímeros/química , Reagentes de Ligações Cruzadas/química , Reagentes de Ligações Cruzadas/farmacologia , Hidrogéis/farmacologia , Ligação de Hidrogênio/efeitos dos fármacos , Micelas , Polietilenoglicóis/química , Polímeros/farmacologia
10.
BMC Infect Dis ; 19(1): 13, 2019 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-30611203

RESUMO

BACKGROUND: Up until now, there are limited studies available on the epidemiology of infectious diseases in Democratic People's Republic of Korea (DPRK, North Korea). However, different types of infectious diseases have been found in North Korean travelers at Dandong port. Entry surveillance data of those North Korean travelers may provide some insight into the probable epidemiology of some infectious diseases in DPRK. METHODS: We actively analyzed the medical test result of North Korean travelers entering China through Dandong port. Detection of hepatitis B virus (HBV), tuberculosis (TB), syphilis and malaria was made by specific laboratory tests according to the national technical guidelines. Infectious diseases surveillance data for 2015-17 was analyzed and compared among subgroups. RESULTS: Between Jan 1, 2014, and Dec 31, 2016, 557 cases of infectious diseases were identified among 18,494 North Korean travelers, HBV active infection (466 cases), active TB infection (33 cases), current active syphilis infection (57) cases, Plasmodium falciparum (P.falciparum) malaria infection (1 case). The incidence of HBV, TB and syphilis in North Korean travelers was high. Incidence of TB increased from 11.7256 (1/10,000) in 2015 to 28.2738 (1/10,000) in 2017. HBV immunization rate in in North Korean travelers was relatively high in 0-10 age group. CONCLUSION: This report is the first to characterize the profile of infectious diseases among arriving North Korean travelers in mainland China. Our findings suggest high incidence of HBV, TB and syphilis among North Korean travelers. The screening for TB in North Korean workers should be strengthened in order to prevent infections imported into China.


Assuntos
Doenças Transmissíveis/epidemiologia , Viagem/estatística & dados numéricos , Adulto , China/epidemiologia , República Democrática Popular da Coreia/etnologia , Feminino , Hepatite B/epidemiologia , Humanos , Incidência , Malária/epidemiologia , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários , Sífilis/epidemiologia , Tuberculose/epidemiologia , Adulto Jovem
11.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 35(3): 488-492, 2018 06 25.
Artigo em Zh | MEDLINE | ID: mdl-29938960

RESUMO

Meniscus injury has been one of the most common knee injuries in current society. The research on artificial meniscus implants as substitutes in meniscus reconstruction therapy has become global focus in order to solve clinical problems such as irreparable meniscus injury and symptoms after full or partial meniscectomy. At present, researches on artificial meniscus implants mainly focus on biodegradable meniscus scaffolds and non-biodegradable meniscus substitutes. Although the commercialized meniscal implants, such as CMI ®, Actifit ® and NUsurface ®, have been applied in the clinical, none of them can perfectively restore or permanently replace the natural meniscus tissue, effectively solve the symptoms after meniscectomy, and prevent cartilage degenerative diseases. The research progress, application, advantages and disadvantages of different kinds of artificial meniscus implants are reviewed in this manuscript, and the prospect is provided.


Assuntos
Traumatismos do Joelho , Menisco , Próteses e Implantes , Lesões do Menisco Tibial , Humanos , Meniscos Tibiais , Lesões do Menisco Tibial/cirurgia
12.
Int J Mol Sci ; 18(3)2017 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-28257066

RESUMO

NF-κB is an important transcription factor that plays critical roles in cell survival, proliferation, inflammation, and cancers. Although the majority of experimentally identified functional NF-κB binding sites (κB sites) match the consensus sequence, there are plenty of non-functional NF-κB consensus sequences in the genome. We analyzed the surrounding sequences of the known κB sites that perfectly match the GGGRNNYYCC consensus sequence and identified the nucleotide at the -1 position of κB sites as a key contributor to the binding of the κB sites by NF-κB. We demonstrated that a cytosine at the -1 position of a κB site (-1C) could be methylated, which thereafter impaired NF-κB binding and/or function. In addition, all -1C κB sites are located in CpG islands and are conserved during evolution only when they are within CpG islands. Interestingly, when there are multiple NF-κB binding possibilities, methylation of -1C might increase NF-κB binding. Our finding suggests that a single nucleotide at the -1 position of a κB site could be a critical factor in NF-κB functioning and could be exploited as an additional manner to regulate the expression of NF-κB target genes.


Assuntos
Sítios de Ligação , Ilhas de CpG , Metilação de DNA , NF-kappa B/metabolismo , Sequência de Bases , Linhagem Celular , Sequência Consenso , Regulação da Expressão Gênica , Humanos , Ligação Proteica
13.
Environ Sci Technol ; 49(20): 12372-9, 2015 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-26426569

RESUMO

Layered manganese oxide, i.e., birnessite was prepared via the reaction of potassium permanganate with ammonium oxalate. The water content in the birnessite was adjusted by drying/calcining the samples at various temperatures (30 °C, 100 °C, 200 °C, 300 °C, and 500 °C). Thermogravimetry-mass spectroscopy showed three types of water released from birnessite, which can be ascribed to physically adsorbed H2O, interlayer H2O and hydroxyl, respectively. The activity of birnessite for formaldehyde oxidation was positively associated with its water content, i.e., the higher the water content, the better activity it has. In-situ DRIFTS and step scanning XRD analysis indicate that adsorbed formaldehyde, which is promoted by bonded water via hydrogen bonding, is transformed into formate and carbonate with the consumption of hydroxyl and bonded water. Both bonded water and water in air can compensate the consumed hydroxyl groups to sustain the mineralization of formaldehyde at room temperature. In addition, water in air stimulates the desorption of carbonate via water competitive adsorption, and accordingly the birnessite recovers its activity. This investigation elucidated the role of water in oxidizing formaldehyde by layered manganese oxides at room temperature, which may be helpful for the development of more efficient materials.


Assuntos
Formaldeído/química , Compostos de Manganês/química , Óxidos/química , Adsorção , Ligação de Hidrogênio , Oxirredução , Permanganato de Potássio , Temperatura , Água/química , Difração de Raios X
14.
Am J Respir Crit Care Med ; 189(4): 475-81, 2014 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-24450377

RESUMO

RATIONALE: Early diagnosis and treatment of tuberculous meningitis saves lives, but current laboratory diagnostic tests lack sensitivity. OBJECTIVES: We investigated whether the detection of intracellular bacteria by a modified Ziehl-Neelsen stain and early secretory antigen target (ESAT)-6 in cerebrospinal fluid leukocytes improves tuberculous meningitis diagnosis. METHODS: Cerebrospinal fluid specimens from patients with suspected tuberculous meningitis were stained by conventional Ziehl-Neelsen stain, a modified Ziehl-Neelsen stain involving cytospin slides with Triton processing, and an ESAT-6 immunocytochemical stain. Acid-fast bacteria and ESAT-6-expressing leukocytes were detected by microscopy. All tests were performed prospectively in a central laboratory by experienced technicians masked to the patients' final diagnosis. MEASUREMENTS AND MAIN RESULTS: Two hundred and eighty patients with suspected tuberculous meningitis were enrolled. Thirty-seven had Mycobacterium tuberculosis cultured from cerebrospinal fluid; 40 had a microbiologically confirmed alternative diagnosis; the rest had probable or possible tuberculous meningitis according to published criteria. Against a clinical diagnostic gold standard the sensitivity of conventional Ziehl-Neelsen stain was 3.3% (95% confidence interval, 1.6-6.7%), compared with 82.9% (95% confidence interval, 77.4-87.3%) for modified Ziehl-Neelsen stain and 75.1% (95% confidence interval, 68.8-80.6%) for ESAT-6 immunostain. Intracellular bacteria were seen in 87.8% of the slides positive by the modified Ziehl-Neelsen stain. The specificity of modified Ziehl-Neelsen and ESAT-6 stain was 85.0% (95% confidence interval, 69.4-93.8%) and 90.0% (95% confidence interval, 75.4-96.7%), respectively. CONCLUSIONS: Enhanced bacterial detection by simple modification of the Ziehl-Neelsen stain and an ESAT-6 intracellular stain improve the laboratory diagnosis of tuberculous meningitis.


Assuntos
Antígenos de Bactérias/líquido cefalorraquidiano , Proteínas de Bactérias/líquido cefalorraquidiano , Leucócitos/microbiologia , Mycobacterium tuberculosis/isolamento & purificação , Tuberculose Meníngea/diagnóstico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/líquido cefalorraquidiano , Criança , Pré-Escolar , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Mycobacterium tuberculosis/imunologia , Estudos Prospectivos , Sensibilidade e Especificidade , Coloração e Rotulagem , Tuberculose Meníngea/líquido cefalorraquidiano , Adulto Jovem
15.
Int J Cancer ; 135(10): 2329-37, 2014 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-24706505

RESUMO

Prion protein (PrPc) has been previously reported to be involved in gastric cancer (GC) development and progression. However, the association between expression of PrPc and GC prognosis is yet poorly characterized. In the present study, the expressions of PrPc and MGr1-Ag/37LRP, a protein interacting with PrPc, were detected using the tissue microarray technique and immunohistochemical method to compare clinicopathological parameters of 238 GC patients. We found that the expressions of PrPc and MGr1-Ag/37LRP were upregulated in GC lesions compared with their expressions in adjacent noncancerous tissues (p<0.01). High expression of PrPc was detected in 37.39% (89/238) of GC patients and positively correlated with the expression of MGr1-Ag/37LRP (r=0.532, p<0.001). PrPc expression was associated with a number of clinicopathological parameters including depth of invasion and lymph node metastasis of the tumor (p<0.001). High expression of PrPc brought a poorer prognosis than low PrPc expression. Moreover, GC patients with high level of PrPc and high level of MGr1-Ag/37LRP had the poorest prognosis. Multivariate survival analysis suggested that, along with other parameters, combined expression of PrPc and MGr1-Ag/37LRP was independent prognostic factors for GC patients. These data indicates that overexpression of PrPc, combined with MGr1-Ag/37LRP, is predictive of poor prognosis in GC and thereby could be used to guide the clinical decision.


Assuntos
Adenocarcinoma/metabolismo , Antígenos de Neoplasias/metabolismo , Biomarcadores Tumorais/metabolismo , Mucosa Gástrica/metabolismo , Proteínas PrPC/metabolismo , Receptores de Laminina/metabolismo , Neoplasias Gástricas/metabolismo , Adenocarcinoma/mortalidade , Adenocarcinoma/secundário , Feminino , Seguimentos , Humanos , Técnicas Imunoenzimáticas , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Estudos Retrospectivos , Neoplasias Gástricas/mortalidade , Neoplasias Gástricas/patologia , Taxa de Sobrevida , Análise Serial de Tecidos , Regulação para Cima
16.
Nat Commun ; 15(1): 5081, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38876991

RESUMO

Stomatal movement is vital for plants to exchange gases and adaption to terrestrial habitats, which is regulated by environmental and phytohormonal signals. Here, we demonstrate that hydrogen peroxide (H2O2) is required for light-induced stomatal opening. H2O2 accumulates specifically in guard cells even when plants are under unstressed conditions. Reducing H2O2 content through chemical treatments or genetic manipulations results in impaired stomatal opening in response to light. This phenomenon is observed across different plant species, including lycopodium, fern, and monocotyledonous wheat. Additionally, we show that H2O2 induces the nuclear localization of KIN10 protein, the catalytic subunit of plant energy sensor SnRK1. The nuclear-localized KIN10 interacts with and phosphorylates the bZIP transcription factor bZIP30, leading to the formation of a heterodimer between bZIP30 and BRASSINAZOLE-RESISTANT1 (BZR1), the master regulator of brassinosteroid signaling. This heterodimer complex activates the expression of amylase, which enables guard cell starch degradation and promotes stomatal opening. Overall, these findings suggest that H2O2 plays a critical role in light-induced stomatal opening across different plant species.


Assuntos
Peróxido de Hidrogênio , Luz , Estômatos de Plantas , Estômatos de Plantas/efeitos da radiação , Estômatos de Plantas/metabolismo , Estômatos de Plantas/fisiologia , Peróxido de Hidrogênio/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos da radiação , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Arabidopsis/genética , Arabidopsis/metabolismo , Arabidopsis/fisiologia , Arabidopsis/efeitos da radiação , Triticum/genética , Triticum/metabolismo , Triticum/fisiologia , Triticum/efeitos da radiação , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Transdução de Sinais , Fosforilação , Gleiquênias/metabolismo , Gleiquênias/efeitos da radiação , Gleiquênias/genética , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Fatores de Transcrição de Zíper de Leucina Básica/genética
17.
Mol Biol Rep ; 40(5): 3723-9, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23526365

RESUMO

Hypoxia-inducible signaling pathway is involved in many pathological processes, such as adaptiveness regulation of plateau environment, myocardial ischemia and tumorigenesis. NDRG1 is a member of the N-myc downregulated gene (NDRG) family, and it has strong hypoxia stress reaction functions. Although the cellular responses to hypoxia are well known, little is known about the interaction between hypoxia-inducible transcription factor (HIF)-1α and NDRG1. In this study, we cloned HIF-1α CDS, NDRG1 promoter and its truncatures, constructed pCDNA3.0-Hif-1α and pGL3-basic-NDRG1. Reporter assay results showed that HIF-1α could bind to NDRG1 promoter to activate NDRG1 expression. Further results revealed that -1202 to -450 of NDRG1 promoter is the most important region for HIF-1α binding. Then, we constructed NDRG1 stable transfection cell line. Results from MTT, colony-forming assay and flow cytometry showed that NDRG1 overexpression results in more proliferation and less apoptosis of A549 lung cancer cells. Our study elucidates the mechanism of NGRG1 in hypoxia stress reactions and may provide new strategy for hypoxia injuries.


Assuntos
Proteínas de Ciclo Celular/genética , Regulação Neoplásica da Expressão Gênica , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/genética , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Regiões Promotoras Genéticas , Apoptose/genética , Hipóxia Celular , Linhagem Celular Tumoral , Proliferação de Células , Expressão Gênica , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Ligação Proteica , Ativação Transcricional , Regulação para Cima
18.
ACS Appl Mater Interfaces ; 15(25): 29801-29812, 2023 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-37306556

RESUMO

In the context of meniscus reconstruction in knee joints, current bulk biomaterials fail to meet the clinical demands for both excellent mechanical strength and low coefficient of friction. In this research, zwitterionic polyurethanes (PUs) with varying sulfobetaine (SB) groups were synthesized as the potential materials for artificial meniscus to investigate the relationship between the structures of SB groups and the performances of PUs. Under the saturation condition of 3 mg/mL hyaluronic acid aqueous solution, PU with long-alkyl chains and SB groups (PU-hSB4) exhibited a good tensile modulus (111.5 MPa) because the hydrophobic interaction of carbon chains was able to maintain the ordered aggregations of hard segment domains. Interestingly, hydrophobic chains in the molecular chain could also improve the tribological performance of PU-hSB4 instead of resulting from the surface roughness of samples, the components of lubricants, and the counterface of samples. A thicker and relatively stable hydration layer of noncrystal water was formed on the surface of PU-hSB4, which exhibited superior resistance to external forces compared to other PUs. Even if the hydration layer was damaged, PU-hSB4 was able to resist the compression of cartilage due to its high surface modulus, thus maintaining a similar and stable coefficient of friction (0.15-0.16) to native meniscus (0.18) and excellent wear resistance. In addition, the low cytotoxicity of PU-hSB4 further demonstrated its great potential to be applied in artificial meniscus instead.

19.
ACS Nano ; 2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36626296

RESUMO

Effective drug delivery and prevention of postoperative recurrence are significant challenges for current glioblastoma (GBM) treatment. Poor drug delivery is mainly due to the presence of the blood-brain barrier (BBB), and postoperative recurrence is primarily due to the resistance of GBM cells to chemotherapeutic drugs and the presence of an immunosuppressive microenvironment. Herein, a biomimetic nanodrug delivery platform based on endogenous exosomes that could efficiently target the brain without targeting modifications and co-deliver pure drug nanomicelles and immune adjuvants for safe and efficient chemo-immunotherapy against GBM is prepared. Inspired by the self-assembly technology of small molecules, tanshinone IIA (TanIIA) and glycyrrhizic acid (GL), which are the inhibitors of signal transducers and activators of transcription 3 from traditional Chinese medicine (TCM), self-assembled to form TanIIA-GL nanomicelles (TGM). Endogenous serum exosomes are selected to coat the pure drug nanomicelles, and the CpG oligonucleotides, agonists of Toll-like receptor 9, are anchored on the exosome membrane to obtain immune exosomes loaded with TCM self-assembled nanomicelles (CpG-EXO/TGM). Our results demonstrate that CpG-EXO/TGM can bind free transferrin in blood, prolong blood circulation, and maintain intact structures when traversing the BBB and targeting GBM cells. In the GBM microenvironment, the strong anti-GBM effect of CpG-EXO/TGM is mainly attributed to two factors: (i) highly efficient uptake by GBM cells and sufficient intracellular release of drugs to induce apoptosis and (ii) stimulation of dendritic cell maturation and induction of tumor-associated macrophages polarization by CpG oligonucleotides to generate anti-GBM immune responses. Further research found that CpG-EXO/TGM can not only produce better efficacy in combination with temozolomide but also prevent a postoperative recurrence.

20.
J Clin Microbiol ; 50(4): 1166-70, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22238448

RESUMO

Tuberculous meningitis leads to a devastating outcome, and early diagnosis and rapid chemotherapy are vital to reduce morbidity and mortality. Since Mycobacterium tuberculosis is a kind of cytozoic pathogen and its numbers are very few in cerebrospinal fluid, detecting M. tuberculosis in cerebrospinal fluid from tuberculous meningitis patients is still a challenge for clinicians. Ziehl-Neelsen stain, the current feasible microbiological method for the diagnosis of tuberculosis, often needs a large amount of cerebrospinal fluid specimen but shows a low detection rate of M. tuberculosis. Here, we developed a modified Ziehl-Neelsen stain, involving cytospin slides with Triton processing, in which only 0.5 ml of cerebrospinal fluid specimens was required. This method not only improved the detection rate of extracellular M. tuberculosis significantly but also identified intracellular M. tuberculosis in the neutrophils, monocytes, and lymphocytes clearly. Thus, our modified method is more effective and sensitive than the conventional Ziehl-Neelsen stain, providing clinicians a convenient yet powerful tool for rapidly diagnosing tuberculous meningitis.


Assuntos
Corantes/química , Mycobacterium tuberculosis , Coloração e Rotulagem/métodos , Tuberculose Meníngea/líquido cefalorraquidiano , Tuberculose Meníngea/diagnóstico , Humanos , Linfócitos/microbiologia , Neutrófilos/microbiologia , Sensibilidade e Especificidade , Tuberculose Meníngea/microbiologia
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