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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.
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
3.
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
4.
Rev Esp Enferm Dig ; 112(2): 109-117, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31830797

RESUMO

BACKGROUND: increasing evidence suggests that marital status is associated with tumor prognosis. The prognostic impact of marital status on colorectal neuroendocrine neoplasms has not been studied adequately. This study explored the relationship between marital status and prognosis of colorectal neuroendocrine neoplasms. METHODS: during 2004-2012, 7,180 colorectal neuroendocrine neoplasm patients were identified from the Surveillance, Epidemiology and End Results database. A primary comparison (married vs unmarried) was performed with a 1:1 propensity matching score. Secondary comparisons were performed individually between three unmarried subgroups (single, divorced/separated, widowed) and the married group. The effect of marital status according to sex and extension of disease was explored. RESULTS: married patients had better survival (overall survival) (p < 0.001) and colorectal neuroendocrine neoplasm cause-specific survival (p = 0.001) rates compared to unmarried patients. Multivariate analysis indicated that marital status was an independent prognostic factor and married patients had a better overall survival (HR = 1.673; 95% CI: 1.446-1.936; p < 0.001) and colorectal neuroendocrine neoplasm cause-specific survival (HR = 1.365; 95% CI: 1.141-1.632; p = 0.001). Subgroup analysis showed that married patients had the best prognosis of cause-specific survival/overall survival and widowed patients had the worst prognosis (log-rank test p < 0.05). Marital status plays a more important role in colorectal neuroendocrine neoplasms patients with localized disease than in those with regional or distant disease. CONCLUSIONS: marital status is an independent prognostic factor for survival in colorectal neuroendocrine neoplasms patients. Married patients have a better prognosis with early stage disease. Single, widowed and male patients are regarded as a high-risk population.


Assuntos
Neoplasias Colorretais , Tumores Neuroendócrinos , Humanos , Masculino , Estado Civil , Tumores Neuroendócrinos/epidemiologia , Prognóstico , Programa de SEER
5.
Nanomedicine ; 14(1): 73-84, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28890109

RESUMO

NIR responsive inorganic hybrid (Ti@GO) was synthesized. It could absorb NIR light and convert it into local hyperthermia and ROS synchronously. Ti@GO was firstly developed as a photosensitizer and a photothermal agent to realize tumor PTT and PDT. For anti-tumor application, HA was grafted on Ti@GO simultaneously as water solubility improver and tumor targeting moiety. ICG was chosen as a model drug. Results demonstrated that HA-Ti@GO could remarkably improve ICG stability and drug accumulation in 4T1 cells, enhance tumor phototherapy efficiency and reduce light-associated side effects. HA-Ti@GO/ICG under NIR laser irradiation showed a significant decreased cell viability of 20.7±2.6% and a high DNA damage degree of 82.4±8.3%. Moreover, in vivo results showed that HA-Ti@GO/ICG plus NIR laser achieved almost complete tumor regression on 4T1 tumor-bearing mice, with a tumor volume of 67.0 mm3. Taken together, our study provided a promising strategy to realize synergistic PTT/PDT tumor therapy with a single NIR light.


Assuntos
Neoplasias da Mama/terapia , Sistemas de Liberação de Medicamentos , Verde de Indocianina/administração & dosagem , Raios Infravermelhos , Nanoestruturas/administração & dosagem , Fototerapia , Animais , Apoptose , Neoplasias da Mama/metabolismo , Corantes/administração & dosagem , Corantes/química , Feminino , Grafite/química , Humanos , Ácido Hialurônico/química , Hipertermia Induzida , Verde de Indocianina/química , Camundongos , Camundongos Endogâmicos BALB C , Nanoestruturas/química , Espécies Reativas de Oxigênio/metabolismo , Titânio/química , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
6.
Neural Plast ; 2017: 7027380, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28770113

RESUMO

Exosomes are bilipid layer-enclosed vesicles derived from endosomes and are released from neural cells. They contain a diversity of proteins, mRNAs, and microRNAs (miRNAs) that are delivered to neighboring cells and/or are transported to distant sites. miRNAs released from exosomes appear to be associated with multiple neurodegenerative conditions linking to Alzheimer's disease (AD) which is marked by hyperphosphorylated tau proteins and accumulation of Aß plaques. Exciting findings reveal that miRNAs released from exosomes modulate the expression and function of amyloid precursor proteins (APP) and tau proteins. These open up the possibility that dysfunctional exosomal miRNAs may influence AD progression. In addition, it has been confirmed that the interaction between miRNAs released by exosomes and Toll-like receptors (TLR) initiates inflammation. In exosome support-deprived neurons, exosomal miRNAs may regulate neuroplasticity to relieve neurological damage. In this review, we summarize the literature on the function of exosomal miRNAs in AD pathology, the potential of these miRNAs as diagnostic biomarkers in AD, and the use of exosomes in the delivery of miRNAs which may lead to major advances in the field of macromolecular drug delivery.


Assuntos
Doença de Alzheimer/diagnóstico , Doença de Alzheimer/metabolismo , Doença de Alzheimer/terapia , Exossomos/metabolismo , MicroRNAs/metabolismo , Doença de Alzheimer/complicações , Animais , Biomarcadores/metabolismo , Encefalite/complicações , Epigênese Genética , Técnicas de Transferência de Genes , Humanos
9.
Neural Plast ; 2016: 4626593, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27057365

RESUMO

Alzheimer's disease (AD) is a progressive neurodegenerative disorder that is characterized by memory loss and cognitive dysfunction. Aquaporin-4 (AQP4), which is primarily expressed in astrocytes, is the major water channel expressed in the central nervous system (CNS). This protein plays an important role in water and ion homeostasis in the normal brain and in various brain pathological conditions. Emerging evidence suggests that AQP4 deficiency impairs learning and memory and that this may be related to the expression of glutamate transporter-1 (GLT-1). Moreover, the colocalization of AQP4 and GLT-1 has long been studied in brain tissue; however, far less is known about the potential influence that the AQP4/GLT-1 complex may have on AD. Research on the functional interaction of AQP4 and GLT-1 has been demonstrated to be of great significance in the study of AD. Here, we review the interaction of AQP4 and GLT-1 in astrocytes, which might play a pivotal role in the regulation of distinct cellular responses that involve neuroprotection against AD. The association of AQP4 and GLT-1 could greatly supplement previous research regarding neuroprotection against AD.


Assuntos
Doença de Alzheimer/metabolismo , Aquaporina 4/metabolismo , Astrócitos/metabolismo , Encéfalo/metabolismo , Transportador 2 de Aminoácido Excitatório/metabolismo , Doença de Alzheimer/genética , Doença de Alzheimer/patologia , Animais , Aquaporina 4/genética , Astrócitos/patologia , Encéfalo/patologia , Transportador 2 de Aminoácido Excitatório/genética , Humanos
10.
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
11.
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
12.
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
13.
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.

14.
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.

15.
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
16.
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.

17.
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.

18.
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
19.
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
20.
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
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