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1.
World J Gastrointest Oncol ; 16(6): 2673-2682, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38994136

RESUMO

BACKGROUND: RAS, BRAF, and mismatch repair (MMR)/microsatellite instability (MSI) are crucial biomarkers recommended by clinical practice guidelines for colorectal cancer (CRC). However, their characteristics and influencing factors in Chinese patients have not been thoroughly described. AIM: To analyze the clinicopathological features of KRAS, NRAS, BRAF, and PIK3CA mutations and the DNA MMR status in CRC. METHODS: We enrolled 2271 Chinese CRC patients at the China-Japan Friendship Hospital. MMR proteins were tested using immunohistochemical analysis, and the KRAS/NRAS/BRAF/PIK3CA mutations were determined using quantitative polymerase chain reaction. Microsatellite status was determined using an MSI detection kit. Statistical analyses were conducted using SPSS software and logistic regression. RESULTS: The KRAS, NRAS, BRAF, and PIK3CA mutations were detected in 44.6%, 3.4%, 3.7%, and 3.9% of CRC patients, respectively. KRAS mutations were more likely to occur in patients with moderate-to-high differentiation. BRAF mutations were more likely to occur in patients with right-sided CRC, poorly differentiated, or no perineural invasion. Deficient MMR (dMMR) was detected in 7.9% of all patients and 16.8% of those with mucinous adenocarcinomas. KRAS, NRAS, BRAF, and PIK3CA mutations were detected in 29.6%, 1.1%, 8.1%, and 22.3% of patients with dMMR, respectively. The dMMR was more likely to occur in patients with a family history of CRC, aged < 50 years, right-sided CRC, poorly differentiated histology, no perineural invasion, and with carcinoma in situ, stage I, or stage II tumors. CONCLUSION: This study analyzed the molecular profiles of KRAS, NRAS, BRAF, PIK3CA, and MMR/MSI in CRC, identifying key influencing factors, with implications for clinical management of CRC.

2.
Hypertens Res ; 47(5): 1273-1287, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38438725

RESUMO

m6A (N6­methyladenosine) is the most common and abundant apparent modification in mRNA of eukaryotes. The modification of m6A is regulated dynamically and reversibly by methyltransferase (writer), demethylase (eraser), and binding protein (reader). It plays a significant role in various processes of mRNA metabolism, including regulation of transcription, maturation, translation, degradation, and stability. Pulmonary arterial hypertension (PAH) is a malignant cardiopulmonary vascular disease characterized by abnormal proliferation of pulmonary artery smooth muscle cells. Despite the existence of several effective and targeted therapies, there is currently no cure for PAH and the prognosis remains poor. Recent studies have highlighted the crucial role of m6A modification in cardiovascular diseases. Investigating the role of RNA m6A methylation in PAH could provide valuable insights for drug development. This review aims to explore the mechanism and function of m6A in the pathogenesis of PAH and discuss the potential targeting of RNA m6A methylation modification as a treatment for PAH.


Assuntos
Adenosina , Hipertensão Arterial Pulmonar , Animais , Humanos , Adenosina/análogos & derivados , Adenosina/metabolismo , Metiltransferases/metabolismo , Metiltransferases/genética , Hipertensão Arterial Pulmonar/genética , Hipertensão Arterial Pulmonar/metabolismo , Metilação de RNA , RNA Mensageiro/metabolismo , RNA Mensageiro/genética
3.
Opt Express ; 31(13): 22001-22011, 2023 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-37381284

RESUMO

The equalization plays a pivotal role in modern high-speed optical wire-line transmission. Taking advantage of the digital signal processing architecture, the deep neural network (DNN) is introduced to realize the feedback-free signaling, which has no processing speed ceiling due to the timing constraint on the feedback path. To save the hardware resource of a DNN equalizer, a parallel decision DNN is proposed in this paper. By replacing the soft-max decision layer with hard decision layer, multi-symbol can be processed within one neural network. The neuron increment during parallelization is only linear with the layer count, rather than the neuron count in the case of duplication. The simulation results show that the optimized new architecture has competitive performance with the traditional 2-tap decision feedback equalizer architecture with 15-tap feed forward equalizer at a 28GBd, or even 56GBd, four-level pulse amplitude modulation signal with 30dB loss. And the training convergency of the proposed equalizer is much faster than its traditional counterpart. An adaptive mechanism of the network parameter based on forward error correction is also studied.

4.
Nat Commun ; 14(1): 2488, 2023 04 29.
Artigo em Inglês | MEDLINE | ID: mdl-37120646

RESUMO

Wildlife is reservoir of emerging viruses. Here we identified 27 families of mammalian viruses from 1981 wild animals and 194 zoo animals collected from south China between 2015 and 2022, isolated and characterized the pathogenicity of eight viruses. Bats harbor high diversity of coronaviruses, picornaviruses and astroviruses, and a potentially novel genus of Bornaviridae. In addition to the reported SARSr-CoV-2 and HKU4-CoV-like viruses, picornavirus and respiroviruses also likely circulate between bats and pangolins. Pikas harbor a new clade of Embecovirus and a new genus of arenaviruses. Further, the potential cross-species transmission of RNA viruses (paramyxovirus and astrovirus) and DNA viruses (pseudorabies virus, porcine circovirus 2, porcine circovirus 3 and parvovirus) between wildlife and domestic animals was identified, complicating wildlife protection and the prevention and control of these diseases in domestic animals. This study provides a nuanced view of the frequency of host-jumping events, as well as assessments of zoonotic risk.


Assuntos
COVID-19 , Quirópteros , Vírus , Animais , Animais Domésticos/virologia , Animais Selvagens/virologia , Animais de Zoológico/virologia , Quirópteros/virologia , Mamíferos/virologia , Pangolins/virologia , Filogenia , Zoonoses/virologia
5.
Neural Regen Res ; 18(4): 819-824, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36204849

RESUMO

Epidural electrical stimulation is a new treatment method for spinal cord injury (SCI). Its efficacy and safety have previously been reported. Rehabilitation treatment after epidural electrical stimulation is important to ensure and improve the postoperative efficacy of epidural electrical stimulation in patients with SCI. Considering that electromyography (EMG)-induced rehabilitation treatment can accurately match the muscle contraction of patients with SCI, we designed a study protocol for a prospective, randomized controlled trial. In this trial, on the premise of adjusting the spinal cord electrical stimulator to obtain the maximum EMG signal of the target muscle, patients with SCI receiving epidural electrical stimulation will undergo EMG-induced rehabilitation treatment. Recovery of muscle strength of key muscles, quality of life, safety and therapeutic effects will be monitored. Twenty patients with SCI who are scheduled to undergo epidural electrical stimulation in Shanghai Ruijin Rehabilitation Hospital will be randomly divided into two groups with 10 patients per group. The control group will receive conventional rehabilitation treatment. The EMG-induced rehabilitation group will receive EMG-induced rehabilitation treatment of the target muscles of the upper and lower limbs based on conventional rehabilitation treatment. After rehabilitation treatment, follow up for all patients will occur at 2 weeks and 1, 3 and 6 months. The primary outcome measure of this trial will be evaluation of target muscle recovery using the Manual Muscle Testing grading scale. Secondary outcome measures will include modified Barthel Index scores, integrated EMG values, the visual analogue scale, Spinal Cord Independence Measure scores, and modified Ashworth scale scores. The safety indicator will be the incidence of adverse events. This trial will collect data regarding the therapeutic effects of EMG-induced rehabilitation in patients with SCI receiving epidural electrical stimulation for 6 months after rehabilitation treatment. Findings from this trial will help develop rehabilitation methods in patients with SCI after epidural electrical stimulation. This study protocol was approved by Ethics Committee of Shanghai Ruijin Rehabilitation Hospital (Approval No. RKIRB2022-12) on February 15, 2022 and was registered with Chinese Clinical Trial Registry (registration number: ChiCTR2200061674; date: June 30, 2022). Study protocol version: 1.0.

6.
World J Gastrointest Oncol ; 14(9): 1699-1710, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-36187391

RESUMO

BACKGROUND: In colorectal cancer, tumor deposits (TDs) are considered to be a prognostic factor in the current staging system, and are only considered in the absence of lymph node metastases (LNMs). However, this definition and the subsequent prognostic value based on it is controversial, with various hypotheses. TDs may play an independent role when it comes to survival and addition of TDs to LNM count may predict the prognosis of patients more accurately. AIM: To assess the prognostic impact of TDs and evaluate the effect of their addition to the LNM count. METHODS: The patients are derived from the Surveillance, Epidemiology, and End Results database. A prognostic analysis regarding impact of TDs on overall survival (OS) was performed using Cox regression model, and other covariates associating with OS were adjusted. The effect of addition of TDs to LNM count on N restaging was also evaluated. The subgroup analysis was performed to explore the different profile of risk factors between patients with and without TDs. RESULTS: Overall, 103755 patients were enrolled with 14131 (13.6%) TD-positive and 89624 (86.4%) TD-negative tumors. TD-positive patients had worse prognosis compared with TD-negative patients, with 3-year OS rates of 47.3% (95%CI, 46.5%-48.1%) and 77.5% (95%CI, 77.2%-77.8%, P < 0.0001), respectively. On multivariable analysis, TDs were associated poorer OS (hazard ratio, 1.35; 95%CI, 1.31-1.38; P < 0.0001). Among TD-positive patients, the number of TDs had a linear negative effect on disease-free survival and OS. After reclassifying patients by adding TDs to the LNM count, 885 of 19 965 (4.4%) N1 patients were restaged as pN2, with worse outcomes than patients restaged as pN1 (3-year OS rate: 78.5%, 95%CI, 77.9%-79.1% vs 63.2%, 95%CI, 60.1%-66.5%, respectively; P < 0.0001). CONCLUSION: TDs are an independent prognostic factor for OS in colorectal cancer. The addition of TDs to LNM count improved the prognostic accuracy of tumor, node and metastasis staging.

7.
Cardiovasc Ther ; 2022: 9615674, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35692375

RESUMO

Purpose: L-carnitine (LC) is considered to have good therapeutic potential for myocardial infarction (MI), but its mechanism has not been clarified. The aim of the study is to elucidate the cardioprotective effects of LC in mice following MI and related mechanisms. Methods: ICR mice were treated with LC for 2 weeks after induction of MI with ligation of left anterior descending artery. Electrocardiographic (ECG) recording and echocardiography were used to evaluate cardiac function. H&E staining, TTC staining, and Masson staining were performed for morphological analysis and cardiac fibrosis. ELISA and immunofluorescence were utilized to detect biomarkers and inflammatory mediators. The key proteins in the Bax/Bcl-2 signaling pathway were also examined by Western blot. Results: Both echocardiography and histological measurement showed an improvement in cardiac function and morphology. Biomarkers such as LDH, NT-proBNP, cTnT, and AST, as well as the inflammatory cytokines IL-1ß, IL-6, and TNF-α, were decreased in plasma of mice receiving LC treatment after myocardial injury. In addition, the expression of α-SMA as well as the key proteins in the Bax/Bcl-2 signaling pathway in cardiac myocardium were much lower in mice with LC treatment compared to those without after MI. Conclusions: Our data suggest that LC can effectively ameliorate left ventricular (LV) remodeling after MI, and its beneficial effects on myocardial function and remodeling may be attributable at least in part to anti-inflammatory and inhibition of the Bax/Bcl-2 apoptotic signaling pathway.


Assuntos
Infarto do Miocárdio , Remodelação Ventricular , Animais , Apoptose , Carnitina/metabolismo , Carnitina/farmacologia , Carnitina/uso terapêutico , Modelos Animais de Doenças , Camundongos , Camundongos Endogâmicos ICR , Miocárdio/patologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Transdução de Sinais , Proteína X Associada a bcl-2/metabolismo
8.
World J Gastrointest Oncol ; 14(2): 525-532, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-35317314

RESUMO

BACKGROUND: Preoperative therapy is widely used in locally advanced rectal cancer. It can improve local control of rectal cancer. However, there are few indicators that can predict the effect of preoperative chemotherapy accurately. AIM: To investigate whether the increase in serum α-fetoprotein (AFP) can predict better efficacy of preoperative chemotherapy. METHODS: This was a retrospective study. We analyzed 125 patients admitted between 2017 and 2019 with locally advanced rectal cancer. All patients received six cycles of preoperative chemotherapy (mFOLFOX6 every 2 wk). Serum AFP of 26 patients rose slightly after three or four cycles of chemotherapy, and fell to normal again within 2 mo. The other 99 patients had a normal level of serum AFP during chemotherapy. Patients were divided into two groups (AFP risen and AFP normal). According to postoperative pathology, we compared tumor regression and complete response rate between the two groups. The primary outcome measure was the tumor regression grade (TRG) after chemotherapy. The difference in pathological complete response between the two groups was also investigated. RESULTS: There were no tumor progression and distant metastasis in both groups during preoperative chemotherapy. Patients in the AFP risen group achieved better TRG 0/1 than those in the AFP normal group (61.5% vs 39.4%). The increase in AFP was a significant predictor for better tumor regression [χ 2 = 4.144, odds ratio (OR) = 2.666, P = 0.04]. In the AFP risen group, the complete response rate was 30.8%, which was higher than in the AFP normal group (30.8% vs 12.1%, χ 2 = 4.542, OR = 3.251, P = 0.03). CONCLUSION: Patients with a slight increase in serum AFP can achieve better tumor regression during preoperative chemotherapy, and are more likely to achieve pathological complete response.

9.
Mol Med Rep ; 25(4)2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35211757

RESUMO

Advanced glycation end products (AGEs) have been widely reported to play an important role in osteoporosis (OP), particularly in diabetes­related OP. The aim of the present study was to investigate the effect of AGEs on osteoblast function and the underlying mechanisms. The level of bone mineral density (BMD), serum AGEs and fasting blood glucose (FBG) was measured in patients with OP and healthy individuals, and the correlation between AGE levels and BMD or FBG was then analyzed. For the in vitro experiments, the hFOB1.19 osteoblast cell line was cultured in medium containing AGEs and serum from healthy individuals or patients with OP, and with or without type­2 diabetes mellitus (T2DM). Cell proliferation, differentiation, mineralization, apoptosis and ferroptosis were evaluated using Cell Counting Kit­8 and alkaline phosphatase (ALP) assays, Alizarin red and TUNEL staining, iron indicator, lipid peroxidation tests and western blot analysis, respectively. In a separate set of experiments, the ferroptosis inhibitor, deferoxamine (DFO), was also added to the culture medium of cells treated with AGEs and serum from patients with OP and T2DM. The results demonstrated that patients with OP had a higher level of serum AGEs and FBG compared with that in healthy individuals. The level of serum AGEs in patients with OP was negatively correlated with BMD, but was positively correlated with FBG. In addition, AGEs and serum from patients with OP markedly inhibited hFOB1.19 cell proliferation, ALP production and mineralized nodule formation. Apoptosis and ferroptosis were significantly promoted by AGEs and serum from patients with OP. Moreover, serum from OP patients with T2DM caused stronger effect than that from OP patients with normal FBG. However, DFO reversed the effects induced by AGEs and serum from patients with OP and T2DM on hFOB1.19 cells. Collectively, AGEs could disrupt the functions of osteoblasts by inducing cell ferroptosis, thus contributing to OP.


Assuntos
Ferroptose , Osteoporose , Diferenciação Celular , Produtos Finais de Glicação Avançada/metabolismo , Humanos , Osteoblastos/metabolismo , Osteoporose/metabolismo
10.
Acta Pharmacol Sin ; 43(4): 840-849, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34267346

RESUMO

Luteolin is a flavonoid in a variety of fruits, vegetables, and herbs, which has shown anti-inflammatory, antioxidant, and anti-cancer neuroprotective activities. In this study, we investigated the potential beneficial effects of luteolin on memory deficits and neuroinflammation in a triple-transgenic mouse model of Alzheimer's disease (AD) (3 × Tg-AD). The mice were treated with luteolin (20, 40 mg · kg-1 · d-1, ip) for 3 weeks. We showed that luteolin treatment dose-dependently improved spatial learning, ameliorated memory deficits in 3 × Tg-AD mice, accompanied by inhibiting astrocyte overactivation (GFAP) and neuroinflammation (TNF-α, IL-1ß, IL-6, NO, COX-2, and iNOS protein), and decreasing the expression of endoplasmic reticulum (ER) stress markers GRP78 and IRE1α in brain tissues. In rat C6 glioma cells, treatment with luteolin (1, 10 µM) dose-dependently inhibited LPS-induced cell proliferation, excessive release of inflammatory cytokines, and increase of ER stress marker GRP78. In conclusion, luteolin is an effective agent in the treatment of learning and memory deficits in 3 × Tg-AD mice, which may be attributable to the inhibition of ER stress in astrocytes and subsequent neuroinflammation. These results provide the experimental basis for further research and development of luteolin as a therapeutic agent for AD.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Doença de Alzheimer/tratamento farmacológico , Animais , Disfunção Cognitiva/tratamento farmacológico , Modelos Animais de Doenças , Estresse do Retículo Endoplasmático , Endorribonucleases/farmacologia , Endorribonucleases/uso terapêutico , Luteolina/farmacologia , Luteolina/uso terapêutico , Camundongos , Camundongos Transgênicos , Doenças Neuroinflamatórias , Proteínas Serina-Treonina Quinases , Ratos
12.
Angew Chem Int Ed Engl ; 60(49): 25878-25883, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34585471

RESUMO

The conformational distribution and mutual interconversion of thermally activated delayed fluorescence (TADF) emitters significantly affect the exciton utilization. However, their influence on the photophysics in amorphous film states is still not known due to the lack of a suitable quantitative analysis method. Herein, we used temperature-dependent time-resolved photoluminescence spectroscopy to quantitatively measure the relative populations of the conformations of a TADF emitter for the first time. We further propose a new concept of "self-doping" for realizing high-efficiency nondoped OLEDs. Interestingly, this "compositionally" pure film actually behaves as a film with a dopant (quasi-equatorial form) in a matrix (quasi-axial form). The concentration-induced quenching that may occur at high concentrations is thus expected to be effectively relieved. The "self-doping" OLED prepared with the newly developed TADF emitter TP2P-PXZ as a neat emitting layer realizes a high maximum external quantum efficiency of 25.4 % and neglectable efficiency roll-off.

13.
Inflamm Res ; 70(7): 789-797, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34165588

RESUMO

OBJECTIVE: Osteoporosis is affecting the health of postmenopausal women in the world. In case of that, we explored whether FK-506 could ameliorate osteoporosis by inhibiting the activated CaN/NFAT pathway during oxidative stress. METHODS: First, the castrated rat model is constructed through the bilateral ovariectomy. Hologic Discovery (S/N 80347) dual-energy X-ray absorptiometry assessed bone mineral density (BMD) implemented at left femur of rats. Next, hematoxylin-eosin (H&E) staining observed and calculated the changes of bone trabecular, mean trabecular plate separation (Tb.Sp), mean trabecular plate thickness (Tb.Th), and bone volume fraction (BV/TV). Then, CCK-8 assay, TUNEL assay, ALP kit and alizarin red staining detected the viability, apoptosis, alkaline phosphatase (ALP) activity, and capacity of mineralization respectively. At last, commercially available kits detected the levels of ROS and SOD in transfected MC3T3-E1 cells and bone tissues, and Western blot analysis detected proteins related to apoptosis and CaN/NFAT pathway. RESULTS: FK-506 increased the BMD and changes of bone trabecular in female castrated rats. FK-506 inhibited the oxidative stress and apoptosis by suppressing the activated CaN/NFAT pathway. Low dose of FK-506 improved the viability, ALP activity, and mineralization capacity. What's more, it suppressed the apoptosis of H2O2-induced MC3T3-E1 cells, which was deteriorated by the high dose of FK-506. Briefly, low dose of FK-506 inhibited the oxidative stress by suppressing the activated CaN/NFAT pathway, while high dose of that further inhibited the oxidative stress by suppressing the CaN/NFAT pathway. CONCLUSION: FK-506 ameliorates osteoporosis resulted from osteoblastic apoptosis which caused by suppressing the activated CaN/NFAT pathway during oxidative stress.


Assuntos
Imunossupressores/uso terapêutico , Osteoporose/tratamento farmacológico , Tacrolimo/uso terapêutico , Fosfatase Alcalina/metabolismo , Animais , Apoptose/efeitos dos fármacos , Densidade Óssea/efeitos dos fármacos , Calcineurina/metabolismo , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Feminino , Fêmur/anatomia & histologia , Fêmur/efeitos dos fármacos , Fêmur/metabolismo , Imunossupressores/farmacologia , Camundongos , Fatores de Transcrição NFATC/metabolismo , Osteoblastos/efeitos dos fármacos , Osteoblastos/metabolismo , Osteoporose/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Ratos Wistar , Transdução de Sinais/efeitos dos fármacos , Tacrolimo/farmacologia , Tíbia/anatomia & histologia , Tíbia/efeitos dos fármacos , Tíbia/metabolismo
14.
Nanoscale ; 13(24): 10798-10806, 2021 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-34106110

RESUMO

Highly conductive, conformable and gel-free electrodes are desirable in human electrophysiology. Besides, intimately coupling with human skin, wearable strain sensors can detect numerous physiological signals, such as wrist pulse and breath. In this study, a multilayer graphene nanosheet film (MGNF) with high conductivity was prepared by the Marangoni self-assembly for using in tattoo dry electrodes (TDEs) and in a graphene tattoo strain sensor (GTSS). Compared to commercial Ag/AgCl gel electrodes, TDEs have lower skin-electrode contact impedance and could detect human electrocardiogram for 24-hour wearing more accurately as well as electromyogram. Through designing a slim serpentine ribbon structure, a resistance-type GTSS, without deterioration even after 2000 cycles, is well demonstrated for human wrist pulse and breath sensing. With the advantages of high conductivity and conformability, MGNF provides support to fabricate low-cost, customizable, and high-performance electronic tattoos for human electrophysiology and strain sensing.


Assuntos
Grafite , Tatuagem , Dispositivos Eletrônicos Vestíveis , Eletrônica , Eletrofisiologia , Humanos
15.
Adv Mater ; 33(24): e2008171, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33963781

RESUMO

Single-crystalline silicon (sc-Si) is the dominant semiconductor material for the modern electronics industry. Despite their excellent photoelectric and electronic properties, the rigidity, brittleness, and nontransparency of commonly used silicon wafers limit their application in transparent flexible optoelectronics. In this study, a new type of Si microstructure, named single-crystalline Si frameworks (sc-SiFs), is developed, through a combination of wet-etching and microfabrication technologies. The sc-SiFs are self-supported, flexible, lightweight, tailorable, and highly transparent. They can withstand a small bending radius of less than 0.5 mm and have a transparency of up to 96% in all wavelength ranges, owing to the hollowed-out framework structures. Thus, the sc-SiFs provide a new platform for high-performance transparent flexible optoelectronics. Taking transparent flexible photodetectors (TFPDs) as an example, substrate-free and self-driven TFPDs are achieved based on the sc-SiFs. The devices exhibit superior performance compared to other reported TFPDs and reveal the great potential for integrated optoelectronic applications. The development of sc-SiFs paves the way toward the fabrication of high-performance transparent flexible devices for a host of applications, including e-skins, the Internet of Things, transparent flexible displays, and artificial visual cortexes.

16.
Pharm Dev Technol ; 26(1): 21-29, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33070673

RESUMO

Multidrug resistance (MDR) is a serious challenge in chemotherapy and also a major threat to breast cancer treatment. As an intracellular energy factory, mitochondria provide energy for drug efflux and are deeply involved in multidrug resistance. Mitochondrial targeted delivery of doxorubicin can overcome multidrug resistance by disrupting mitochondrial function. By incorporating a reactive oxygen species (ROS)-responsive hydrophobic group into the backbone structure of hyaluronic acid - a natural ligand for the highly expressed CD44 receptor on tumor surfaces, a novel ROS-responsive and CD44-targeting nano-carriers was constructed. In this study, mitochondria-targeted triphenylphosphine modified-doxorubicin (TPP-DOX) and amphipathic ROS-responsive hyaluronic acid derivatives (HA-PBPE) were synthesized and confirmed by 1H NMR. The nanocarriers TPP-DOX @ HA-PBPE was prepared in a regular shape and particle size of approximately 200 nm. Compared to free DOX, its antitumor activity in vitro and tumor passive targeting in vivo has been enhanced. The ROS-responsive TPP-DOX@HA-PBPE nanocarriers system provide a promising strategy for the reverse of MDR and efficient delivery of doxorubicin derivatives into drug-resistant cancer cells.


Assuntos
Antineoplásicos/metabolismo , Neoplasias da Mama/metabolismo , Doxorrubicina/metabolismo , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Nanopartículas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/química , Neoplasias da Mama/tratamento farmacológico , Relação Dose-Resposta a Droga , Doxorrubicina/administração & dosagem , Doxorrubicina/química , Portadores de Fármacos/administração & dosagem , Portadores de Fármacos/química , Portadores de Fármacos/metabolismo , Sistemas de Liberação de Medicamentos/métodos , Resistência a Múltiplos Medicamentos/fisiologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/fisiologia , Feminino , Humanos , Células MCF-7 , Camundongos , Camundongos Nus , Nanopartículas/administração & dosagem , Nanopartículas/química , Espécies Reativas de Oxigênio/química
17.
Biochem Genet ; 59(2): 475-490, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33123835

RESUMO

The aim of the present study was to determine the function of microRNA (miR)-125b-5p in lumbar disc degeneration (LDD). Nucleus pulposus (NP) cells were stimulated with 10 ng/ml IL-1ß for 24 h to establish an LDD model. Reverse transcription-quantitative PCR was used to assess miR-125b-5p levels in human lumbar degenerative NP samples and IL-1ß-treated NP cells. An interaction between miR-125b-5p and TP53-regulated inhibitor of apoptosis 1 (TRIAP1) was revealed by TargetScan 7.1 and dual-luciferase reporter assay. Protein levels of pro-inflammatory factors were determined using ELISA. Cell viability and apoptosis were evaluated by MTT and flow cytometry analysis, respectively. miR-125b-5p was markedly upregulated in both human lumbar degenerative NP specimens and IL-1ß-treated NP cells. TRIAP1, which directly targets miR-125b-5p, was markedly downregulated in human lumbar degenerative NP specimens and IL-1ß-treated NP cells. The levels of TNF-α and IL-6 were inhibited in IL-1ß-treated NP cells transfected with miR-125b-5p inhibitor. Moreover, miR-125b-5p inhibitor increased NP cell viability, prevented apoptosis and repressed the apoptotic peptidase activating factor 1/caspase 9 pathway in IL-1ß-treated NP cells. Thus, the present findings suggested that miR-125b-5p could regulate LDD by adjusting NP cell apoptosis and inflammatory responses via TRIAP1.


Assuntos
Apoptose , Interleucina-1beta/metabolismo , Degeneração do Disco Intervertebral/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , MicroRNAs/metabolismo , Núcleo Pulposo/metabolismo , Células Cultivadas , Humanos , Inflamação/metabolismo , Inflamação/patologia , Degeneração do Disco Intervertebral/patologia , Núcleo Pulposo/patologia
18.
J Am Soc Nephrol ; 31(6): 1282-1295, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32444356

RESUMO

BACKGROUND: Antiglomerular basement membrane (anti-GBM) disease is associated with HLA-DRB1*1501 (the major predisposing genetic factor in the disease), with α3127-148 as a nephritogenic T and B cell epitope. Although the cause of disease remains unclear, the association of infections with anti-GBM disease has been long suspected. METHODS: To investigate whether microbes might activate autoreactive T and B lymphocytes via molecular mimicry in anti-GBM disease, we used bioinformatic tools, including BLAST, SYFPEITHI, and ABCpred, for peptide searching and epitope prediction. We used sera from patients with anti-GBM disease to assess peptides recognized by antibodies, and immunized WKY rats and a humanized mouse model (HLA-DR15 transgenic mice) with each of the peptide candidates to assess pathogenicity. RESULTS: On the basis of the critical motif, the bioinformatic approach identified 36 microbial peptides that mimic human α3127-148. Circulating antibodies in sera from patients with anti-GBM recognized nine of them. One peptide, B7, derived from Actinomyces species, induced proteinuria, linear IgG deposition on the GBM, and crescent formation when injected into WKY rats. The antibodies to B7 also targeted human and rat α3127-148. B7 induced T cell activation from human α3127-148-immunized rats. T cell responses to B7 were detected in rats immunized by Actinomyces lysate proteins or recombinant proteins. We confirmed B7's pathogenicity in HLA-DR15 transgenic mice that developed kidney injury similar to that observed in α3135-145-immunized mice. CONCLUSIONS: Sera from patients with anti-GBM disease recognized microbial peptides identified through a bioinformatic approach, and a peptide from Actinomyces induced experimental anti-GBM GN by T and B cell crossreactivity. These studies demonstrate that anti-GBM disease may be initiated by immunization with a microbial peptide.


Assuntos
Actinomyces/imunologia , Doença Antimembrana Basal Glomerular/etiologia , Proteínas de Bactérias/imunologia , Animais , Doença Antimembrana Basal Glomerular/imunologia , Antígenos B7/imunologia , Colágeno Tipo IV/imunologia , Subtipos Sorológicos de HLA-DR/fisiologia , Humanos , Ativação Linfocitária , Camundongos , Peptídeos/imunologia , Ratos , Ratos Endogâmicos WKY , Linfócitos T/imunologia
19.
Nature ; 583(7815): 286-289, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32380510

RESUMO

The current outbreak of coronavirus disease-2019 (COVID-19) poses unprecedented challenges to global health1. The new coronavirus responsible for this outbreak-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-shares high sequence identity to SARS-CoV and a bat coronavirus, RaTG132. Although bats may be the reservoir host for a variety of coronaviruses3,4, it remains unknown whether SARS-CoV-2 has additional host species. Here we show that a coronavirus, which we name pangolin-CoV, isolated from a Malayan pangolin has 100%, 98.6%, 97.8% and 90.7% amino acid identity with SARS-CoV-2 in the E, M, N and S proteins, respectively. In particular, the receptor-binding domain of the S protein of pangolin-CoV is almost identical to that of SARS-CoV-2, with one difference in a noncritical amino acid. Our comparative genomic analysis suggests that SARS-CoV-2 may have originated in the recombination of a virus similar to pangolin-CoV with one similar to RaTG13. Pangolin-CoV was detected in 17 out of the 25 Malayan pangolins that we analysed. Infected pangolins showed clinical signs and histological changes, and circulating antibodies against pangolin-CoV reacted with the S protein of SARS-CoV-2. The isolation of a coronavirus from pangolins that is closely related to SARS-CoV-2 suggests that these animals have the potential to act as an intermediate host of SARS-CoV-2. This newly identified coronavirus from pangolins-the most-trafficked mammal in the illegal wildlife trade-could represent a future threat to public health if wildlife trade is not effectively controlled.


Assuntos
Betacoronavirus/genética , Betacoronavirus/isolamento & purificação , Eutérios/virologia , Evolução Molecular , Genoma Viral/genética , Homologia de Sequência do Ácido Nucleico , Animais , Betacoronavirus/classificação , COVID-19 , China , Quirópteros/virologia , Chlorocebus aethiops , Proteínas do Envelope de Coronavírus , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/patologia , Infecções por Coronavirus/transmissão , Infecções por Coronavirus/veterinária , Infecções por Coronavirus/virologia , Proteínas M de Coronavírus , Proteínas do Nucleocapsídeo de Coronavírus , Reservatórios de Doenças/virologia , Genômica , Especificidade de Hospedeiro , Humanos , Pulmão/patologia , Pulmão/virologia , Malásia , Proteínas do Nucleocapsídeo/genética , Pandemias , Fosfoproteínas , Filogenia , Pneumonia Viral/epidemiologia , Pneumonia Viral/transmissão , Pneumonia Viral/virologia , Reação em Cadeia da Polimerase , Recombinação Genética , SARS-CoV-2 , Alinhamento de Sequência , Análise de Sequência de RNA , Glicoproteína da Espícula de Coronavírus/genética , Células Vero , Proteínas do Envelope Viral/genética , Proteínas da Matriz Viral/genética , Zoonoses/transmissão , Zoonoses/virologia
20.
J Bone Miner Res ; 35(10): 2015-2031, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32460388

RESUMO

Despite the best treatment, approximately 10% of fractures still face undesirable repair. Recently, many studies have focused on the importance of macrophages in bone repair; however, the cellular mechanisms by which they work are not yet fully understood. In this study, we explored the functions of macrophage G-protein-coupled receptor interacting protein 1 (GIT1) in healing a tibial monocortical defect model. Using GIT1flox/flox Lyz2-Cre (GIT1 CKO) mice, we observed that a GIT1 deficiency in the macrophages led to an exacerbation of interleukin 1ß (IL1ß) production, more M1-like macrophage infiltration, and impaired intramembranous ossification in vivo. The results of in vitro assays further indicated that the macrophage GIT1 plays a critical role in several cellular processes in response to lipopolysaccharide (LPS), such as anti-oxidation, IL1ß production alleviation, and glycolysis control. Although GIT1 has been recognized as a scaffold protein, our data clarified that GIT1-mediated extracellular-signal-regulated kinase (ERK) phosphorylation could activate nuclear factor (erythroid-derived 2)-like 2 (NRF2) in macrophages after LPS treatment. Moreover, we demonstrated that macrophage GIT1-activated ERK/NRF2 negatively regulates the 6-phosphofructo-2-kinase/fructose-2, 6-biphosphatase 3 (PFKFB3), facilitating the decrease of glycolysis. Our findings uncovered a previously unrecognized role of GIT1 in regulating ERK/NRF2 in macrophages to control the inflammatory response, suggesting that macrophage GIT1 could be a potential target to improve bone regeneration. © 2020 The Authors. Journal of Bone and Mineral Research published by American Society for Bone and Mineral Research..


Assuntos
Regeneração Óssea , Proteínas de Ciclo Celular/fisiologia , MAP Quinases Reguladas por Sinal Extracelular , Proteínas Ativadoras de GTPase/fisiologia , Macrófagos , Fator 2 Relacionado a NF-E2 , Animais , Inflamação , Camundongos
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