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1.
Anal Chem ; 96(16): 6390-6397, 2024 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-38608159

RESUMO

Although gastric cancer (GC) is one of the most frequent malignant tumors in the digestive tract with high morbidity and mortality, it remains a diagnostic dilemma due to its reliance on invasive biopsy or insensitive assays. Herein, we report a fluorescent gastric cancer reporter (FGCR) with activatable near-infrared fluorescence (NIRF) signals and high renal-clearance efficiency for the detection of orthotopic GC in a murine model via real-time imaging and remote urinalysis. In the presence of gastric-tumor-associated ß-galactosidase (ß-Gal), FGCR can be fluorescently activated for in vivo NIRF imaging. Relying on its high renal-clearance efficiency (∼95% ID), it can be rapidly excreted through kidneys to urine for the ultrasensitive detection of tumors with a diameter down to ∼2.1 mm and for assessing the prognosis of oxaliplatin-based chemotherapy. This study not only provides a new approach for noninvasive auxiliary diagnosis and prognosis of GC but also provides guidelines for the development of fluorescence probes for cancer diagnosis.


Assuntos
Corantes Fluorescentes , Imagem Óptica , Neoplasias Gástricas , beta-Galactosidase , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/urina , Neoplasias Gástricas/patologia , Animais , beta-Galactosidase/metabolismo , Corantes Fluorescentes/química , Humanos , Camundongos , Linhagem Celular Tumoral , Camundongos Nus
2.
Chem Biol Interact ; 382: 110618, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37394161

RESUMO

Gastric cancer (GC) is a highly aggressive and deadly disease worldwide. Given the limitations of current treatments, it is crucial to discover more effective antitumor drugs. Here, we demonstrated that arthpyrone M (Art-M), a novel 4-hydroxy-2-pyridone alkaloid derived from the marine fungus Arthrinium arundinis, inhibited the proliferation, invasion and migration of GC both in vivo and in vitro. The underlying mechanism of Art-M in GC cells was explored by RNA-sequencing analysis, qRT-PCR and immunoblotting, which demonstrated that Art-M significantly suppressed the mTORC1 pathway by decreasing phosphorylated mTOR and p70S6K. Moreover, Art-M feedback increased the activities of AKT and ERK. Co-immunoprecipitation and immunoblotting analysis revealed that Art-M induced dissociation of Raptor from mTOR and promoted Raptor degradation, leading to the inhibition of mTORC1 activity. Art-M was identified as a novel and potent mTORC1 antagonist. Furthermore, Art-M enhanced GC cell sensitivity to apatinib, and the combination of Art-M and apatinib showed better efficacy in the treatment of GC. Taken together, these results demonstrate that Art-M is a promising candidate drug for the treatment of GC by suppressing the mTORC1 pathway.


Assuntos
Alcaloides , Antineoplásicos , Neoplasias Gástricas , Humanos , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Neoplasias Gástricas/patologia , Linhagem Celular Tumoral , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Proliferação de Células , Alcaloides/farmacologia , Alcaloides/uso terapêutico , Fungos , Proteínas Proto-Oncogênicas c-akt/metabolismo
3.
Signal Transduct Target Ther ; 8(1): 185, 2023 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-37183231

RESUMO

Genomic MET amplification and exon 14 skipping are currently clinically recognized biomarkers for stratifying subsets of non-small cell lung cancer (NSCLC) patients according to the predicted response to c-Met inhibitors (c-Metis), yet the overall clinical benefit of this strategy is quite limited. Notably, c-Met protein overexpression, which occurs in approximately 20-25% of NSCLC patients, has not yet been clearly defined as a clinically useful biomarker. An optimized strategy for accurately classifying patients with c-Met overexpression for decision-making regarding c-Meti treatment is lacking. Herein, we found that SYK regulates the plasticity of cells in an epithelial state and is associated with their sensitivity to c-Metis both in vitro and in vivo in PDX models with c-Met overexpression regardless of MET gene status. Furthermore, TGF-ß1 treatment resulted in SYK transcriptional downregulation, increased Sp1-mediated transcription of FRA1, and restored the mesenchymal state, which conferred resistance to c-Metis. Clinically, a subpopulation of NSCLC patients with c-Met overexpression coupled with SYK overexpression exhibited a high response rate of 73.3% and longer progression-free survival with c-Meti treatment than other patients. SYK negativity coupled with TGF-ß1 positivity conferred de novo and acquired resistance. In summary, SYK regulates cell plasticity toward a therapy-sensitive epithelial cell state. Furthermore, our findings showed that SYK overexpression can aid in precisely stratifying NSCLC patients with c-Met overexpression regardless of MET alterations and expand the population predicted to benefit from c-Met-targeted therapy.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Fator de Crescimento Transformador beta1 , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Células Epiteliais/metabolismo , Quinase Syk/genética
4.
Front Nutr ; 9: 850063, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35694167

RESUMO

Objective: This study aimed to assess the prognostic value of the Nutritional Risk Score 2002 (NRS2002) and patient-generated subjective global assessment (PG-SGA) for post-operative infections in patients with gastric cancer (GC) and colorectal cancer (CRC) who underwent curative surgery. Methods: This prospective study included 1,493 GC patients and 879 CRC patients who underwent curative surgery at 18 hospitals in China between April 2017 and March 2020. The NRS2002 and PG-SGA were performed on the day of admission. The relationship between the nutritional status of patients before surgery and post-surgical incidence of infection was analyzed using univariate and multiple logistic regression analyses. Results: According to NRS2002, the prevalence of nutritional risk was 51.1% in GC patients and 63.9% in CRC patients. According to the PG-SGA, 38.9% of GC patients and 54.2% of CRC patients had malnutrition. Approximately 4.4% of the GC patients and 9.9% of the CRC patients developed infectious complications after surgery. The univariate and multiple logistic regression analyses showed that the risk of infections was significantly higher in GC patients with a high nutritional risk score (NRS2002 ≥5) than in those with a low score (NRS2002 <3), and the PG-SGA score was identified as a predictor of post-operative infection complications of CRC. Conclusion: The pre-operative nutritional status of patients with GC or CRC has an impact on post-operative infection occurrence. NRS2002 ≥5 was a risk factor for post-operative infection in patients with GC, and the PG-SGA B/C was a predictor of infections in patients with CRC.

5.
Front Plant Sci ; 13: 894840, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35498711

RESUMO

Numerous studies have shown that plant shading can promote the quality of green tea. However, the association of shading with metabolic regulation in tea leaves and roots remains unelucidated. Here, the metabolic profiling of two tea cultivars ("Xiangfeicui" and "Jinxuan") in response to shading and relighting periods during the summer season was performed using non-targeted metabolomics methods. The metabolic pathway analyses revealed that long-term shading remarkably inhibit the sugar metabolism such as glycolysis, galactose metabolism, and pentose phosphate pathway in the leaves and roots of "Xiangfeicui," and "Jinxuan" were more sensitive to light recovery changes. The lipid metabolism in the leaves and roots of "Xiangfeicui" was promoted by short-term shading, while it was inhibited by long-term shading. In addition, the intensity of the flavonoid metabolites in the leaves and roots of "Jinxuan" were upregulated with a trend of rising first and then decreasing under shading, and five flavonoid synthesis genes showed the same trend (F3H, F3'5'H, DFR, ANS, and ANR). Simultaneously, the amino acids of the nitrogen metabolism in the leaves and roots of the two cultivars were significantly promoted by long-term shading, while the purine and caffeine metabolism was inhibited in the leaves of "Xiangfeicui." Interestingly, CsGS1.1 and CsTSI, amino acid synthase genes was upregulated in the leaves and roots of two cultivars. These results indicated that shading could participate in carbon and nitrogen metabolic regulation of both leaf and root, and root metabolism could have a positive association with leaf metabolism to promote the shaded tea quality.

6.
Methods Mol Biol ; 2432: 73-84, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35505208

RESUMO

Methylation data, similar to other omics data, is susceptible to various technical issues that are potentially associated with unexplained or unrelated factors. Any difference in the measurement of DNA methylation, such as laboratory operation and sequencing platform, may lead to batch effects. With the accumulation of large-scale omics data, scientists are making joint efforts to generate and analyze omics data to answer various scientific questions. However, batch effects are inevitable in practice, and careful adjustment is needed. Multiple statistical methods for controlling bias and inflation between batches have been developed either by correcting based on known batch factors or by estimating directly from the output data. In this chapter, we will review and demonstrate several popular methods for batch effect correction and make practical recommendations in epigenome-wide association studies (EWAS).


Assuntos
Epigenoma , Estudo de Associação Genômica Ampla , Viés , Metilação de DNA , Estudo de Associação Genômica Ampla/métodos , Análise de Sequência
7.
Curr Biol ; 31(24): 5473-5486.e6, 2021 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-34727523

RESUMO

Medium spiny neurons (MSNs) constitute the vast majority of striatal neurons and the principal interface between dopamine reward signals and functionally diverse cortico-basal ganglia circuits. Information processing in these circuits is dependent on distinct MSN types: cell types that are traditionally defined according to their projection targets or dopamine receptor expression. Single-cell transcriptional studies have revealed greater MSN heterogeneity than predicted by traditional circuit models, but the transcriptional landscape in the primate striatum remains unknown. Here, we set out to establish molecular definitions for MSN subtypes in Rhesus monkeys and to explore the relationships between transcriptionally defined subtypes and anatomical subdivisions of the striatum. Our results suggest at least nine MSN subtypes, including dorsal striatum subtypes associated with striosome and matrix compartments, ventral striatum subtypes associated with the nucleus accumbens shell and olfactory tubercle, and an MSN-like cell type restricted to µ-opioid receptor rich islands in the ventral striatum. Although each subtype was demarcated by discontinuities in gene expression, continuous variation within subtypes defined gradients corresponding to anatomical locations and, potentially, functional specializations. These results lay the foundation for achieving cell-type-specific transgenesis in the primate striatum and provide a blueprint for investigating circuit-specific information processing.


Assuntos
Corpo Estriado , Neurônios , Animais , Corpo Estriado/fisiologia , Dopamina/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Neostriado , Neurônios/fisiologia , Primatas
8.
Nat Commun ; 12(1): 6276, 2021 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-34725325

RESUMO

Triple-negative breast cancer (TNBC) is a collection of biologically diverse cancers characterized by distinct transcriptional patterns, biology, and immune composition. TNBCs subtypes include two basal-like (BL1, BL2), a mesenchymal (M) and a luminal androgen receptor (LAR) subtype. Through a comprehensive analysis of mutation, copy number, transcriptomic, epigenetic, proteomic, and phospho-proteomic patterns we describe the genomic landscape of TNBC subtypes. Mesenchymal subtype tumors display high mutation loads, genomic instability, absence of immune cells, low PD-L1 expression, decreased global DNA methylation, and transcriptional repression of antigen presentation genes. We demonstrate that major histocompatibility complex I (MHC-I) is transcriptionally suppressed by H3K27me3 modifications by the polycomb repressor complex 2 (PRC2). Pharmacological inhibition of PRC2 subunits EZH2 or EED restores MHC-I expression and enhances chemotherapy efficacy in murine tumor models, providing a rationale for using PRC2 inhibitors in PD-L1 negative mesenchymal tumors. Subtype-specific differences in immune cell composition and differential genetic/pharmacological vulnerabilities suggest additional treatment strategies for TNBC.


Assuntos
Antineoplásicos/farmacologia , Neoplasias de Mama Triplo Negativas/genética , Animais , Metilação de DNA , Dosagem de Genes , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Genômica , Antígenos de Histocompatibilidade Classe I/genética , Antígenos de Histocompatibilidade Classe I/metabolismo , Humanos , Camundongos , Proteínas do Grupo Polycomb/antagonistas & inibidores , Proteínas do Grupo Polycomb/genética , Proteínas do Grupo Polycomb/metabolismo , Proteogenômica , Proteômica , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/metabolismo
9.
J Med Case Rep ; 15(1): 553, 2021 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-34749789

RESUMO

BACKGROUND: Boerhaave's syndrome is the spontaneous rupture of the esophagus, which requires early diagnosis and treatment. Symptoms may vary, and diagnosis can be challenging. CASE PRESENTATION: Case 1: A 54-year-old Chinese man presented to us with sudden-onset epigastric pain radiating to the back following hematemesis. Upper gastrointestinal endoscopy revealed a full-thickness rupture of the esophageal wall. Subsequent computed tomography showed frank pneumomediastinum and heterogeneous pleural effusion. Immediately, esophageal perforation repair operation and jejunostomy were performed. The postoperative period was uneventful, and he was discharged. Case 2: A 62-year-old Chinese man was admitted to the emergency department with thoracic dull pain and chest distress. Chest computed tomography scan showed pneumomediastinum and large left-sided pleural effusion. Esophagus fistula was confirmed by contrast esophagography. Then, we performed thoracotomy to repair the esophageal tear as well as to debride and irrigate the left pleural space. His postoperative period was uneventful, with no leakage or stricture. Case 3: The patient was a 69-year-old Chinese male presenting with severe retrosternal and upper abdominal pain following an episode of forceful vomiting. Thoracic computed tomography scan revealed a rupture in the left distal part of the esophagus, a pneumomediastinum, and left-sided pleural effusions. Conservative treatment failed to improve disease conditions. Open thoracic surgery was performed with debridement and drainage of the mediastinum and the pleural cavity, after which he made a slow but full recovery. CONCLUSIONS: We highlight that early diagnosis and appropriate surgical treatment are essential for optimum outcome in patients with esophageal rupture. We emphasize the importance of critical care support, particularly in the early stages of management.


Assuntos
Perfuração Esofágica , Doenças do Mediastino , Derrame Pleural , Idoso , Perfuração Esofágica/diagnóstico por imagem , Perfuração Esofágica/cirurgia , Humanos , Masculino , Doenças do Mediastino/diagnóstico por imagem , Doenças do Mediastino/cirurgia , Pessoa de Meia-Idade , Derrame Pleural/diagnóstico por imagem , Derrame Pleural/cirurgia , Ruptura Espontânea/diagnóstico por imagem , Ruptura Espontânea/cirurgia
11.
Front Plant Sci ; 12: 720800, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34567034

RESUMO

Camellia sinensis cv. 'Yanlingyinbiancha' is a leaf-variegated mutant with stable genetic traits. The current study aimed to reveal the differences between its albino and green tissues, and the molecular mechanism underlying the variegation. Anatomic analysis showed the chloroplasts of albino tissues to have no intact lamellar structure. Photosynthetic pigment in albino tissues was significantly lower than that in green tissues, whereas all catechin components were more abundant in the former. Transcriptome analysis revealed most differentially expressed genes involved in the biosynthesis of photosynthetic pigment, photosynthesis, and energy metabolism to be downregulated in albino tissues while most of those participating in flavonoid metabolism were upregulated. In addition, it was found cryptochrome 1 (CRY1) and phytochrome B (PHYB) genes that encode blue and red light photoreceptors to be downregulated. These photoreceptors mediate chloroplast protein gene expression, chloroplast protein import and photosynthetic pigment biosynthesis. Simultaneously, SUS gene, which was upregulated in albino tissues, encodes sucrose synthase considered a biochemical marker for sink strength. Collectively, we arrived to the following conclusions: (1) repression of the biosynthesis of photosynthetic pigment causes albinism; (2) destruction of photoreceptors in albino tissues suppresses photomorphogenesis, leading to abnormal chloroplast development; (3) albino tissues receive sucrose from the green tissues and decompose their own storage substances to obtain the energy needed for survival; and (4) UV-B signal and brassinosteroids promote flavonoid biosynthesis.

12.
Nano Converg ; 8(1): 10, 2021 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-33796911

RESUMO

Iron-based nanoparticles, which could elicit ferroptosis, is becoming a promising new way to inhibit tumor cell growth. Notably, ultrasmall iron oxide nanoparticles (USIONPs) have been found to upregulate the autophagy process in glioblastoma (GBM) cells. Whether USIONPs could also elicit ferroptosis and the relationship between the USIONPs-induced autophagy and ferroptosis need to be explored. In the current study, our synthesized USIONPs with good water solubility could significantly upregulate the ferroptosis markers in GBM cells, and downregulate the expression of anti-ferroptosis genes. Interestingly,ferrostatin-1 could reverse USIONPs- induced ferroptosis, but inhibitors of apoptosis, pyroptosis, or necrosis could not. Meanwhile, autophagy inhibitor 3-methyladenine could also reverse the USIONPs-induced ferroptosis. In addition, shRNA silencing of upstream genes Beclin1/ATG5 of autophagy process could significantly reverse USIONPs-induced ferroptosis, whereas overexpression of Beclin1/ATG5 of autophagy process could remarkably promote USIONPs-induced ferroptosis. Furthermore, lysosome inhibitors could significantly reverse the USIONPs-induced ferroptosis. Collectively, these facts suggest that USIONPs-induced ferroptosis is regulated via Beclin1/ATG5-dependent autophagy pathway.

13.
J Drug Target ; 29(1): 108-120, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32795132

RESUMO

It is important to enhance penetration depth of nanomedicine and realise rapid drug release simultaneously at targeted tumour for improving anti-tumour efficiency of chemotherapeutic drugs. This project employed sodium alginate (Alg) as matrix material, to establish tumour-responsive nanogels with particle size conversion and drug controlled release functions. Specifically, tumour-targeting peptide CRGDK was conjugated with Alg first (CRGDK-Alg). Then, doxorubicin (DOX) was efficiently encapsulated in CRGDK-FeAlg nanogel during the cross-linking process (CRGDK-FeAlg/DOX). This system was closed during circulation. Once reaching tumour, the particle size of nanogels was reduced to ∼25 nm, which facilitated deep penetration of DOX in tumour tissues. After entering tumour cells, the size of nanogels was further reduced to ∼10 nm and DOX was released simultaneously. Meanwhile, FeAlg efficiently catalysed H2O2 to produce •OH by Fenton reaction, achieving local chemodynamic therapy without O2 mediation. Results showed CRGDK-FeAlg/DOX significantly inhibited tumour proliferation in vivo with V/V0 of 1.13 after treatment, significantly lower than that of control group with V/V0 of 4.79.


Assuntos
Alginatos/síntese química , Antibióticos Antineoplásicos/síntese química , Doxorrubicina/síntese química , Sistemas de Liberação de Medicamentos/métodos , Tamanho da Partícula , Células A549 , Alginatos/administração & dosagem , Animais , Antibióticos Antineoplásicos/administração & dosagem , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Preparações de Ação Retardada/administração & dosagem , Preparações de Ação Retardada/síntese química , Doxorrubicina/administração & dosagem , Feminino , Humanos , Células MCF-7 , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Ensaios Antitumorais Modelo de Xenoenxerto/métodos
15.
Plant Physiol Biochem ; 156: 484-493, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33038691

RESUMO

Tea plants are important economic perennial crops that can be negatively impacted by drought stress (DS). However, their survival strategies in long-term DS conditions and the accumulation and influence of metabolites and mineral elements (MEs) in their organs, when facing hydraulic vulnerability segmentation, require further investigation. The MEs and metabolites in the leaf, stem, and root after long-term DS (20 d) were examined here, using inductively coupled plasma optical emission spectrometry (ICP-OES) and liquid chromatograph-mass spectrometry (LC-MS). The accumulation patterns of 116 differentially accumulated metabolites (DAMs) and nine MEs were considerably affected in all organs. The concentration of all MEs varied significantly in at least one organ, while the K and Ca levels were markedly altered in all three. Most DAM levels increased in the stem but decreased in the root and leaf, implying that vulnerability segmentation may occur with long-term DS. The typical nitrogen- and carbon-compound levels similarly increased in the stem and decreased in the leaf and root, as the plant might respond to long-term DS by stabilizing respiration, promoting nitrogen recycling, and free radical scavenging. Correlation analysis showed several possible DAM-ME interactions and an association between Mn and flavonoids. Thus, survival strategies under long-term DS included sacrificing distal/vulnerable organs and accumulating function-specialized metabolites and MEs to mitigate drought-induced oxidative damage. This is the first study that reports substance fluctuations after long-term DS in different organs of plants, and highlights the need to use whole plants to fully comprehend stress response strategies.


Assuntos
Camellia sinensis/fisiologia , Secas , Estresse Fisiológico , Flavonoides , Folhas de Planta/fisiologia , Raízes de Plantas/fisiologia , Caules de Planta/fisiologia
16.
J Inorg Biochem ; 210: 111127, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32521288

RESUMO

Ru (II) compounds have potential application in photodynamic therapy (PDT). In the current study, two Ru (II) compounds based on the auxiliary ligand 2,2'-bipyridine (bipy) by changing main ligands 5-(2-pyridyl) tetrazole (Hpytz) and di(2H-tetrazol-5-yl) amine (H2datz) have been successfully synthesized and characterized, [Ru (pytz)(bipy)2][PF6] (1) and [Ru(Hdatz)(bipy)2][PF6] (2). These compounds can form nanoparticles (NPs) by nano-precipitation. And [Ru(pytz)(bipy)2][PF6] NPs with a lower half maximal inhibitory concentration (IC50) of 37 µg/mL on HeLa cells than that of [Ru(Hdatz)(bipy)2][PF6] NPs (65 µg/mL). Meanwhile, negligible dark toxicity has been also observed for these NPs even under high concentrations. The results show that [Ru(pytz)(bipy)2][PF6] (1) and [Ru(Hdatz)(bipy)2][PF6] (2) NPs can inhibit cell proliferation in vitro, and may be potential candidates for photodynamic therapy.


Assuntos
Antineoplásicos/farmacologia , Complexos de Coordenação/farmacologia , Fármacos Fotossensibilizantes/farmacologia , Tetrazóis/farmacologia , Antineoplásicos/química , Antineoplásicos/efeitos da radiação , Movimento Celular/efeitos dos fármacos , Complexos de Coordenação/química , Complexos de Coordenação/efeitos da radiação , Fluorescência , Corantes Fluorescentes/química , Corantes Fluorescentes/farmacologia , Corantes Fluorescentes/efeitos da radiação , Células HeLa , Humanos , Ligantes , Luz , Nanopartículas/química , Nanopartículas/efeitos da radiação , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/efeitos da radiação , Rutênio/química , Rutênio/efeitos da radiação , Oxigênio Singlete/metabolismo , Tetrazóis/química , Tetrazóis/efeitos da radiação
17.
Science ; 368(6495): 1122-1127, 2020 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-32381589

RESUMO

Immunological memory specific to previously encountered antigens is a cardinal feature of adaptive lymphoid cells. However, it is unknown whether innate myeloid cells retain memory of prior antigenic stimulation and respond to it more vigorously on subsequent encounters. In this work, we show that murine monocytes and macrophages acquire memory specific to major histocompatibility complex I (MHC-I) antigens, and we identify A-type paired immunoglobulin-like receptors (PIR-As) as the MHC-I receptors necessary for the memory response. We demonstrate that deleting PIR-A in the recipient or blocking PIR-A binding to donor MHC-I molecules blocks memory and attenuates kidney and heart allograft rejection. Thus, innate myeloid cells acquire alloantigen-specific memory that can be targeted to improve transplant outcomes.


Assuntos
Rejeição de Enxerto/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , Imunidade Inata , Memória Imunológica , Macrófagos/imunologia , Monócitos/imunologia , Receptores Imunológicos/fisiologia , Animais , Deleção de Genes , Rejeição de Enxerto/genética , Transplante de Coração , Transplante de Rim , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Mutantes , Receptores Imunológicos/genética
18.
Biomater Sci ; 8(9): 2481-2487, 2020 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-32202278

RESUMO

Naturally available compounds with bioactivity are potential candidates for cancer treatment. In this paper, we isolated hypericin (HC) from Hypericum sinense L. and investigated its antitumor activity both in vitro and in vivo. The nanoparticles (NPs) of HC were prepared by a nanoprecipitation process with 1,2-distearoyl-sn-glycero-3-phospho-ethanolamine-N-[methoxy(polyethylene glycol)-2000] (DSPE-PEG-2000). With light irradiation, HC NPs not only undergo efficient electron transfer to generate the superoxide radical (O2-˙) and the hydroxyl radical (OH˙) as well as energy transfer producing singlet oxygen (1O2) for photodynamic therapy (PDT), but also non-radiative decay to produce heat for photothermal therapy (PTT) with a photothermal conversion efficiency of 29.3%. This synergistic therapy, therefore, largely boosts the phototherapy efficacy of HC NPs on human cervical cancer cells (HeLa), guaranteeing a low half maximal inhibitory concentration (IC50) of only 5.6 µg mL-1. Furthermore, in vivo studies suggest that HC NPs are capable of inhibiting tumor proliferation after laser irradiation, and the main organs remain healthy, including the heart, kidneys, liver, lungs and spleen. Our results indicate that HC NPs derived from nature with excellent phototherapy efficacies are biocompatible candidates for type I PDT/PTT synergistic cancer therapy.


Assuntos
Antineoplásicos/administração & dosagem , Nanopartículas/administração & dosagem , Perileno/análogos & derivados , Fotoquimioterapia , Terapia Fototérmica , Radiossensibilizantes/administração & dosagem , Animais , Antracenos , Antineoplásicos/farmacocinética , Linhagem Celular Tumoral , Elétrons , Feminino , Células HeLa , Humanos , Lasers , Masculino , Camundongos Nus , Neoplasias/patologia , Neoplasias/terapia , Perileno/administração & dosagem , Perileno/farmacocinética , Fosfatidiletanolaminas/administração & dosagem , Fosfatidiletanolaminas/farmacocinética , Polietilenoglicóis/administração & dosagem , Polietilenoglicóis/farmacocinética , Radiossensibilizantes/farmacologia , Ratos Sprague-Dawley , Carga Tumoral
19.
Ecotoxicol Environ Saf ; 192: 110315, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32058162

RESUMO

Tea (Camellia sinensis), widely planted in the south of China, and often exposed to acid rain. However, research concerning the impacts of acid rain on physiology and biochemistry of tea plants is still scarce. In this study, we investigated the influence of simulated acid rain (SAR) on plant height, root length, photosynthetic pigment, Fv/Fm, proline, malondialdehyde, antioxidant enzyme activity, total nitrogen, caffeine, catechins, and free amino acids. Our results showed that SAR at pH 4.5 did not hinder plant development because growth characteristics, photosynthesis, and ascorbate peroxidase and catalase activities did not decrease at this pH compared to those at the other investigated pH values. However, at pH 3.5 and pH 2.5, the activities of antioxidase and concentrations of malondialdehyde and proline increased significantly in response to the decrease of photosynthetic pigments and Fv/Fm. In addition, the increase in acidity increased total nitrogen, certain amino acid content (theanine, cysteine), and decreased catechin and caffeine contents, resulting in an imbalance of the carbon and nitrogen metabolisms. Our results indicated that SAR at pH 3.5 and pH 2.5 could restrict photosynthesis and the antioxidant defense system, causing metabolic disorders and ultimately affecting plant development and growth, but SAR at pH 4.5 had no toxic effects on tea seedlings when no other stress factors are involved.


Assuntos
Chuva Ácida/toxicidade , Camellia sinensis/efeitos dos fármacos , Aminoácidos/metabolismo , Antioxidantes/metabolismo , Ascorbato Peroxidases/metabolismo , Cafeína/análise , Camellia sinensis/química , Camellia sinensis/crescimento & desenvolvimento , Camellia sinensis/metabolismo , Catalase/metabolismo , Catequina/metabolismo , Malondialdeído/metabolismo , Nitrogênio/análise , Estresse Oxidativo , Fotossíntese/efeitos dos fármacos , Folhas de Planta/metabolismo , Plântula/química , Plântula/efeitos dos fármacos , Plântula/crescimento & desenvolvimento , Plântula/metabolismo
20.
Ecotoxicol Environ Saf ; 190: 110090, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31874405

RESUMO

Cadmium (Cd), a toxic heavy metal, restrains the growth and development of plants and threatens global food safety. Many studies on the alleviation of heavy metal toxicity by exogenous phytohormones have emerged, but reports on tea (Camellia sinensis) are still scarce. In this study, the effects of indole acetic acid (IAA) (2 µM and 10 µM) on Cd uptake and on the physiological and biochemical characteristics of the 'Xiangfeicui' tea cultivar were investigated for the first time. The order of Cd accumulation in tea seedlings was root > stem > mature leaf > tender leaf. Under Cd stress (30 mg kg-1), photosynthetic pigment levels, antioxidant enzyme activity, root vigor, root IAA content, and the levels of most metabolites (including caffeine, soluble sugar, total amino acids, some amino acid components, and most catechins) were significantly reduced, while levels of malondialdehyde, proline, epicatechin, and some amino acids increased. We therefore propose that by reducing Cd accumulation, exogenous IAA can lessen the adverse effects of Cd on the physiology and biochemistry of tea seedlings, promoting the growth of healthier tea plants.


Assuntos
Cádmio/análise , Camellia sinensis/química , Ácidos Indolacéticos/metabolismo , Poluentes do Solo/análise , Antioxidantes/metabolismo , Cádmio/metabolismo , Cádmio/toxicidade , Fotossíntese/efeitos dos fármacos , Reguladores de Crescimento de Plantas/metabolismo , Folhas de Planta/metabolismo , Plântula/efeitos dos fármacos , Poluentes do Solo/metabolismo , Poluentes do Solo/toxicidade , Chá
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