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1.
Sensors (Basel) ; 24(5)2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38475133

RESUMO

As the frequency of natural disasters increases, the study of emergency communication becomes increasingly important. The use of federated learning (FL) in this scenario can facilitate communication collaboration between devices while protecting privacy, greatly improving system performance. Considering the complex geographic environment, the flexible mobility and large communication radius of unmanned aerial vehicles (UAVs) make them ideal auxiliary devices for wireless communication. Using the UAV as a mobile base station can better provide stable communication signals. However, the number of ground-based IoT terminals is large and closely distributed, so if all of them transmit data to the UAV, the UAV will not be able to take on all of the computation and communication tasks because of its limited energy. In addition, there is competition for spectrum resources among many terrestrial devices, and all devices transmitting data will bring about an extreme shortage of resources, which will lead to the degradation of model performance. This will bring indelible damage to the rescue of the disaster area and greatly threaten the life safety of the vulnerable and injured. Therefore, we use user scheduling to select some terrestrial devices to participate in the FL process. In order to avoid the resource waste generated by the terrestrial device resource prediction, we use the multi-armed bandit (MAB) algorithm for equipment evaluation. Considering the fairness issue of selection, we try to replace the single criterion with multiple criteria, using model freshness and energy consumption weighting as reward functions. The state of the art of our approach is demonstrated by simulations on the datasets.

2.
Protein Pept Lett ; 31(3): 169-177, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38343045

RESUMO

BACKGROUND: Heat-labile uracil-DNA glycosylase (HL-UDG) is commonly employed to eliminate carry-over contamination in DNA amplifications. However, the prevailing HL-UDG is markedly inactivated at 50°C, rendering it unsuitable for specific one-step RT-qPCR protocols utilizing reverse transcriptase at an optimal temperature of 42°C. OBJECTIVE: This study aimed to explore novel HL-UDG with lower inactivation temperature and for recombinant expression. METHODS: The gene encoding an HL-UDG was cloned from the cold-water fish rainbow trout (Oncorhynchus mykiss) and expressed in Escherichia coli with high yield. The thermostability of this enzyme and other enzymatic characteristics were thoroughly examined. The novel HL-UDG was then applied for controlling carry-over contamination in one-step RT-qPCR. RESULTS: This recombinantly expressed truncated HL-UDG of rainbow trout (OmUDG) exhibited high amino acids similarity (84.1% identity) to recombinant Atlantic cod UDG (rcUDG) and was easily denatured at 40°C. The optimal pH of OmUDG was 8.0, and the optimal concentrations of both Na+ and K+ were 10 mM. Since its inactivation temperature was lower than that of rcUDG, the OmUDG could be used to eliminate carry-over contamination in one-step RT-qPCR with moderate reverse transcription temperature. CONCLUSION: We successfully identified and recombinantly expressed a novel HL-UDG with an inactivation temperature of 40°C. It is suitable for eliminating carry-over contamination in one-step RT-qPCR.


Assuntos
Temperatura Alta , Oncorhynchus mykiss , Uracila-DNA Glicosidase , Oncorhynchus mykiss/genética , Animais , Uracila-DNA Glicosidase/metabolismo , Uracila-DNA Glicosidase/genética , Uracila-DNA Glicosidase/química , Estabilidade Enzimática , Proteínas Recombinantes/genética , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Escherichia coli/genética , Proteínas de Peixes/genética , Proteínas de Peixes/química , Proteínas de Peixes/metabolismo , Reação em Cadeia da Polimerase em Tempo Real/métodos , Clonagem Molecular
3.
Orphanet J Rare Dis ; 19(1): 54, 2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38336719

RESUMO

BACKGROUND: Patients with relapsing polychondritis (RP) sometimes experience upper airway collapse or lower airway stenosis, and bronchoscopy may provide a valuable typical image to confirm the diagnosis. This study aimed to identify potential risk factors associated with severe adverse effects during bronchoscopy. METHODS: We performed a retrospective cohort study of 82 consecutive patients with RP hospitalized at Peking Union Medical College Hospital between January 1, 2012 and December 31, 2022. Clinical features and disease patterns were compared among patients with RP undergoing bronchoscopy with or without severe adverse effects. Binary logistic regression analysis was performed to identify the associated risk factors. RESULTS: For patients with RP undergoing bronchoscopy with severe adverse effects, the forced vital capacity (FVC), forced vital capacity percent predicted values (FVC%), and peak expiratory flow were significantly lower (P = 0.001, P = 0.001, and P = 0.021, respectively) than those in the non-severe adverse effect subgroup. Binary logistic regression analysis revealed that low FVC% (odds ratio, 0.930; 95% confidence interval, 0.880-0.982; P = 0.009) was an independent risk factor for severe adverse events in patients undergoing bronchoscopy. CONCLUSIONS: Low FVC or FVC% suggests a high risk of severe adverse effects in patients with RP undergoing bronchoscopy. Patients with such risk factors should be carefully evaluated before bronchoscopy and adequately prepared for emergency tracheal intubation or tracheostomy.


Assuntos
Broncoscopia , Policondrite Recidivante , Humanos , Broncoscopia/efeitos adversos , Broncoscopia/métodos , Estudos Retrospectivos , Policondrite Recidivante/complicações , Policondrite Recidivante/diagnóstico , Testes de Função Respiratória , Fatores de Risco
4.
Orphanet J Rare Dis ; 18(1): 353, 2023 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-37951939

RESUMO

BACKGROUND: Autoimmune pulmonary alveolar proteinosis (aPAP) is a rare interstitial lung disease. COVID-19 is associated with worse prognosis in previous lung diseases patients. But the prognosis of aPAP patients after infection with COVID-19 is unclear. In December 2022, China experienced a large-scale outbreak of Omicron variant of the SARS-CoV-2. In this study, we aim to explore the clinical outcomes of aPAP patients infected with COVID-19. RESULTS: A total of 39 aPAP patients were included in this study. 30.77% patients had a decrease in oxygen saturation after COVID-19 infection. We compared the two groups of patients with or without decreased oxygen saturation after COVID-19 infection and found that patients who had previous oxygen therapy (decreased oxygen saturation vs. non decreased oxygen saturation: 6/12 vs. 4/27, P = 0.043), with lower baseline arterial oxygen partial pressure (74.50 ± 13.61 mmHg vs. 86.49 ± 11.92 mmHg, P = 0.009), lower baseline DLCO/VA% [77.0 (74.3, 93.6) % vs. 89.5 (78.2, 97.4) %, P = 0.036], shorter baseline 6MWD [464 (406, 538) m vs. 532 (470, 575) m, P = 0.028], higher disease severity score (P = 0.017), were more likely to have decreased oxygen saturation after COVID-19 infection. CONCLUSION: aPAP patients with poor baseline respiration have a higher probability of hypoxia after COVID-19 infection, but fatal events were rare.


Assuntos
Doenças Autoimunes , COVID-19 , Proteinose Alveolar Pulmonar , Humanos , SARS-CoV-2 , Doenças Autoimunes/tratamento farmacológico , Oxigênio
5.
J Med Virol ; 95(9): e29098, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37707416

RESUMO

In China, the emergence of a nationally widespread epidemic infection of severe acute respiratory syndrome coronavirus 2 (SARS-COV-2) has appeared within a month since December 7, 2022. To evaluate the risk factors for suffering from coronavirus disease 2019 (COVID-19) pneumonia due to infection with SARS-CoV-2 in different kinds of interstitial lung disease (ILD) patients with diverse immunizations, we conducted this retrospective study on 525 patients with ILDs who underwent regular follow-up in our ILD clinic. Among them, 128 ILD patients (24.4%) suffered from COVID-19 pneumonia after SARS-CoV-2 infection. Patients were older with a male predominance in the pneumonia group than in the nonpneumonia group (65.0 ± 10.0 years vs. 56.4 ± 11.7 years, p < 0.001, 55.5% vs. 39.5%, p = 0.002, respectively). Connective tissue disease-associated ILD (CTD-ILD) (25%), idiopathic pulmonary fibrosis (23.4%), and interstitial pneumonia with autoimmune features (21.1%) were the main pre-existing ILDs in the pneumonia group. In Cox multivariable analysis, only male sex and corticosteroid use were risk factors for COVID-19 pneumonia after infection. Two or three doses of vaccination were a protective factor for pre-existing ILD patients suffering from COVID-19 pneumonia. More than two doses of vaccination were strongly recommended for pre-existing ILD patients, particularly for males who were administered corticosteroids.


Assuntos
COVID-19 , Doenças Pulmonares Intersticiais , Pneumonia , Feminino , Humanos , Masculino , COVID-19/complicações , COVID-19/epidemiologia , População do Leste Asiático , Doenças Pulmonares Intersticiais/complicações , Doenças Pulmonares Intersticiais/epidemiologia , Pandemias , Estudos Retrospectivos , Fatores de Risco , SARS-CoV-2 , Pessoa de Meia-Idade , Idoso
6.
Front Med (Lausanne) ; 10: 1157922, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37293302

RESUMO

Usual interstitial pneumonia is the most common type of microscopic polyangiitis (MPA)-associated interstitial lung disease, and patients may initially present with isolated pulmonary fibrosis, which often leads to a misdiagnosis of idiopathic pulmonary fibrosis (IPF). Here, we describe a patient who developed fever of unknown origin, microscopic hematuria and renal insufficiency, who then tested positive for antineutrophil cytoplasmic antibody (ANCA) and was diagnosed with MPA after receiving antifibrotic medication for IPF (original diagnosis) for almost 10 years. The patient's symptoms were ameliorated after administration of additional glucocorticoids and immunosuppressants.

7.
IEEE Trans Image Process ; 32: 3136-3149, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37227918

RESUMO

Benefiting from the intuitiveness and naturalness of sketch interaction, sketch-based video retrieval (SBVR) has received considerable attention in the video retrieval research area. However, most existing SBVR research still lacks the capability of accurate video retrieval with fine-grained scene content. To address this problem, in this paper we investigate a new task, which focuses on retrieving the target video by utilizing a fine-grained storyboard sketch depicting the scene layout and major foreground instances' visual characteristics (e.g., appearance, size, pose, etc.) of video; we call such a task "fine-grained scene-level SBVR". The most challenging issue in this task is how to perform scene-level cross-modal alignment between sketch and video. Our solution consists of two parts. First, we construct a scene-level sketch-video dataset called SketchVideo, in which sketch-video pairs are provided and each pair contains a clip-level storyboard sketch and several keyframe sketches (corresponding to video frames). Second, we propose a novel deep learning architecture called Sketch Query Graph Convolutional Network (SQ-GCN). In SQ-GCN, we first adaptively sample the video frames to improve video encoding efficiency, and then construct appearance and category graphs to jointly model visual and semantic alignment between sketch and video. Experiments show that our fine-grained scene-level SBVR framework with SQ-GCN architecture outperforms the state-of-the-art fine-grained retrieval methods. The SketchVideo dataset and SQ-GCN code are available in the project webpage https://iscas-mmsketch.github.io/FG-SL-SBVR/.

8.
Chest ; 164(1): 137-148, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36801466

RESUMO

BACKGROUND: Lymphangioleiomyomatosis is a progressive diffuse cystic lung disease with approximately 85% survival at 10 years. The determinants of disease progression and mortality after the introduction of sirolimus therapy and vascular endothelial growth factor D (VEGF-D) as a biomarker have not been well defined. RESEARCH QUESTION: Which factors, including VEGF-D and sirolimus therapy, influence disease progression and survival prognosis in patients with lymphangioleiomyomatosis? STUDY DESIGN AND METHODS: The progression dataset and the survival dataset included 282 and 574 patients, respectively, from Peking Union Medical College Hospital, Beijing, China. A mixed-effects model was used to compute the rate of decline in FEV1, and generalized linear models were used to identify variables affecting FEV1 decline. A Cox proportional hazards model was used to explore the association between clinical variables and the outcomes of death or lung transplantation in patients with lymphangioleiomyomatosis. RESULTS: VEGF-D levels and sirolimus treatment were associated with FEV1 changes and survival prognosis. Compared with patients with VEGF-D of < 800 pg/mL at baseline, patients with VEGF-D of ≥ 800 pg/mL lost FEV1 faster (SE, -38.86 mL/y; 95% CI, -73.90 to -3.82 mL/y; P = .031). The 8-year cumulative survival rates of patients with VEGF-D of ≥ 2,000 pg/mL and < 2,000 pg/mL were 82.9% and 95.1%, respectively (P = .014). The generalized linear regression model also demonstrated the benefit of delaying the decline of FEV1 by 65.56 mL/y (95% CI, 29.06-102.06 mL/y) in patients treated with sirolimus compared with those without sirolimus (P < .001). The 8-year risk of death was reduced by 85.1% (hazard ratio, 0.149; 95% CI, 0.075-0.299) after sirolimus treatment. After inverse treatment probability weighting, the risks of death in the sirolimus group were reduced by 85.6%. CT scan results of grade III severity were associated with worse progression than results of grades I or II severity. Patients with baseline FEV1 of 70% predicted or St. George's Respiratory Questionnaire Symptoms domain 50 or higher predicted a higher risk of worse survival. INTERPRETATION: Serum VEGF-D levels, a biomarker of lymphangioleiomyomatosis, are associated with disease progression and survival. Sirolimus therapy is associated with slower disease progression and better survival in patients with lymphangioleiomyomatosis. TRIAL REGISTRY: ClinicalTrials.gov; No.: NCT03193892; URL: www. CLINICALTRIALS: gov.


Assuntos
Neoplasias Pulmonares , Linfangioleiomiomatose , Humanos , Linfangioleiomiomatose/tratamento farmacológico , Fator D de Crescimento do Endotélio Vascular/metabolismo , Sirolimo/uso terapêutico , Biomarcadores , Progressão da Doença , Neoplasias Pulmonares/tratamento farmacológico
9.
Clin Exp Med ; 23(6): 2321-2330, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36715832

RESUMO

This study aimed to explore the general characteristics and spectrum of hospitalized Chinese patients suffering from lung cancer with concomitant interstitial lung disease (LC-ILD). Furthermore, we compared their features before and after the period of immunotherapy for lung cancer. A retrospective analysis of the clinical characteristics of hospitalized LC patients with definite pathological diagnoses was performed from 2014 to 2021. ILD was defined after the review of chest CT imaging. There were 13,085 hospitalized LC patients. Among them, 509 patients (3.89%) had 551 cases of ILD. There were variable underlying causes of ILD, including idiopathic interstitial pneumonia (360 patients), LC treatment-associated ILD (134 cases), and connective tissue disease-associated ILD (55 patients). Although most LC-ILD patients were suffering from adenocarcinoma (204/40.1%), SCLC patients were prone to concomitant ILD (10.8% of all SCLC cases), followed by SCC (9.6% of all SCC cases). All but 10 LC-ILD patients received anti-LC treatment; however, only 39 (10.8%) LC-IIP patients received anti-ILD treatment. There were more LC-ILD patients in the 2018-2021 group than in the 2014-2017 group (5.16% vs. 2.03%, p < 0.001). The underlying causes of ILD were significantly different between the 2018-2021 group and the 2014-2017 group (p < 0.001). After adjusting for the number of hospitalized patients having the same LC pathological pattern, SCLC was determined to be the most likely to be concomitant with ILD, followed by SCC. Most LC-ILD patients were scheduled for anti-LC therapy; however, treatments for concomitant IIP were usually ignored. LC treatment-associated ILD should receive more attention than before.


Assuntos
Pneumonias Intersticiais Idiopáticas , Doenças Pulmonares Intersticiais , Neoplasias Pulmonares , Humanos , Estudos Retrospectivos , População do Leste Asiático , Doenças Pulmonares Intersticiais/complicações , Pneumonias Intersticiais Idiopáticas/complicações , Neoplasias Pulmonares/complicações , Neoplasias Pulmonares/terapia
10.
IEEE Trans Image Process ; 31: 3737-3751, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35594232

RESUMO

Sketch-based image retrieval (SBIR) is a long-standing research topic in computer vision. Existing methods mainly focus on category-level or instance-level image retrieval. This paper investigates the fine-grained scene-level SBIR problem where a free-hand sketch depicting a scene is used to retrieve desired images. This problem is useful yet challenging mainly because of two entangled facts: 1) achieving an effective representation of the input query data and scene-level images is difficult as it requires to model the information across multiple modalities such as object layout, relative size and visual appearances, and 2) there is a great domain gap between the query sketch input and target images. We present SceneSketcher-v2, a Graph Convolutional Network (GCN) based architecture to address these challenges. SceneSketcher-v2 employs a carefully designed graph convolution network to fuse the multi-modality information in the query sketch and target images and uses a triplet training process and end-to-end training manner to alleviate the domain gap. Extensive experiments demonstrate SceneSketcher-v2 outperforms state-of-the-art scene-level SBIR models with a significant margin.

11.
Nanoscale ; 14(6): 2119-2135, 2022 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-35088781

RESUMO

Diabetes mellitus has become one of the most challenging public health problems today. There are still various deficiencies that remain in existing therapeutic drugs. With increasing prevalence and mortality rates, more effective therapeutic agents are required for treatment clinically. As a kind of polyphenol and as a natural product, mangiferin has numerous pharmacological and excellent effects. In this review, the underlying mechanisms of mangiferin on diabetes mellitus and complications will be summarized. Moreover, mangiferin belongs to the BSC IV class and the clinical application and development of mangiferin are limited due to its poor aqueous solubility and fat solubility as well as low bioavailability. Our review also elaborated on improving the solubility of mangiferin by changing the dosage form and introduced the existing results, which hope to provide useful reference for mangiferin for further treating diabetes. In conclusion, mangiferin might be a potential adjuvant therapy for the treatment of diabetes mellitus and complications in the future.


Assuntos
Diabetes Mellitus , Xantonas , Disponibilidade Biológica , Diabetes Mellitus/tratamento farmacológico , Humanos , Solubilidade , Xantonas/uso terapêutico
12.
Front Med ; 16(1): 150-155, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34302615

RESUMO

Cystic fibrosis (CF) is a rare autosomal recessive disease with only one pathogenic gene cystic fibrosis transmembrane conductance regulator (CFTR). To identify the potential pathogenic mutations in a Chinese patient with CF, we conducted Sanger sequencing on the genomic DNA of the patient and his parents and detected all 27 coding exons of CFTR and their flanking intronic regions. The patient is a compound heterozygote of c.2909G > A, p.Gly970Asp in exon 18 and c.1210-3C > G in cis with a poly-T of 5T (T5) sequence, 3 bp upstream in intron 9. The splicing effect of c.1210-3C > G was verified via minigene assay in vitro, indicating that wild-type plasmid containing c.1210-3C together with T7 sequence produced a normal transcript and partial exon 10-skipping-transcript, whereas mutant plasmid containing c.1210-3G in cis with T5 sequence caused almost all mRNA to skip exon 10. Overall, c.1210-3C > G, the newly identified pathogenic mutation in our patient, in combination with T5 sequence in cis, affects the CFTR gene splicing and produces nearly no normal transcript in vitro. Moreover, this patient carries a p.Gly970Asp mutation, thus confirming the high-frequency of this mutation in Chinese patients with CF.


Assuntos
Regulador de Condutância Transmembrana em Fibrose Cística , Fibrose Cística , China , Fibrose Cística/genética , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Humanos , Mutação , Poli T , RNA Mensageiro/genética
13.
J Nanobiotechnology ; 19(1): 412, 2021 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-34876145

RESUMO

Recently, DNA nanostructures with vast application potential in the field of biomedicine, especially in drug delivery. Among these, tetrahedral DNA nanostructures (TDN) have attracted interest worldwide due to their high stability, excellent biocompatibility, and simplicity of modification. TDN could be synthesized easily and reproducibly to serve as carriers for, chemotherapeutic drugs, nucleic acid drugs and imaging probes. Therefore, their applications include, but are not restricted to, drug delivery, molecular diagnostics, and biological imaging. In this review, we summarize the methods of functional modification and application of TDN in cancer treatment. Also, we discuss the pressing questions that should be targeted to increase the applicability of TDN in the future.


Assuntos
DNA , Sistemas de Liberação de Medicamentos , Nanoestruturas , Neoplasias/tratamento farmacológico , Animais , DNA/química , DNA/uso terapêutico , Humanos , Camundongos , Nanoestruturas/química , Nanoestruturas/uso terapêutico
14.
J Agric Food Chem ; 69(42): 12456-12464, 2021 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-34647728

RESUMO

Neural stem cell (NSC) differentiation and proliferation are important biological processes in the cerebral neural network. However, these two abilities of NSCs are limited. Thus, the induction of differentiation and/or proliferation through the administration of plant-derived small-molecule compounds could be used to repair damaged neural networks. The present study reported that gallic acid (GA), an important phenolic acid found in tea, selectively caused NSCs to differentiate into immature neurons and promoted NSC proliferation by activating the mitogen-activated protein kinase/extracellular-regulated kinase (MAPK/ERK) pathway. In addition, it was found that 3,4-dihydroxybenzoic acid was the main active structure exhibiting neurotrophic activity. The substitution of the carboxyl group on the benzene ring with the ester group may promote differentiation based on the structure of 3,4-dihydroxybenzoic acid. Furthermore, the introduction of the 5-hydroxyl group may promote proliferation. The present study identified that GA can promote the differentiation and proliferation of NSCs in vitro and exert pharmacological activity on NSCs.


Assuntos
Quinases de Proteína Quinase Ativadas por Mitógeno , Células-Tronco Neurais , Animais , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Ácido Gálico/farmacologia , Sistema de Sinalização das MAP Quinases , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Células-Tronco Neurais/metabolismo , Neurônios/metabolismo , Ratos
17.
Nanoscale ; 13(21): 9577-9589, 2021 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-33998643

RESUMO

Improving the deep penetration of nanoparticles and realizing the combination of chemotherapy and immunotherapy have become a promising strategy for cancer treatment. Herein, a nuclear-targeted tetrahedral DNA nanostructure (NLS-TDNs, NT) was synthesized to construct matrix metalloproteinase (MMP-2) sensitive hydrogels as delivery vehicles with co-loaded disulfide cross-linked polyethyleneimine (PSP)/nuclear-targeted tetrahedral DNA (NLS-TDNs, NT)/doxorubicin (DOX) nanoparticles (NPs) (PSP/NT/DOX NPs and PNT/DOX NPs) and an immune adjuvant imiquimod (R837) to realize a combination of chemotherapy and immunization for metastatic breast cancer. Due to the membrane-breaking ability of the PNT/DOX NPs, the nanoparticles could effectively achieve deep penetration into tumor tissues, and the in situ generation of tumor-associated antigens by PNT/DOX elicited a strong immune response in the presence of R837, achieving a chemo-immune combination therapy of breast cancer, inducing the maturation of dendritic cells (DCs) and secretion of related cytokines, such as interleukin-6 (IL-6), interleukin-12 (IL-12p70) and tumor necrosis factor (TNF-α) in vitro. The combination significantly promoted the proportions of cytotoxic T cells (CD8+ CTL) and cytotoxic T cells/regulatory T cells (CD8+ CTL/Treg) (5.52% and 11.46%, respectively) and the secretion of cytokines, which cooperatively eradicated primary tumor growth (the tumor growth inhibition (TGI) value was 78.3%) and inhibited the tumor from metastasizing effectively in vivo. Our study provided the basis for activating the antitumor immune system to realize chemo-immunotherapy and tumor metastasis therapy.


Assuntos
Neoplasias da Mama , Nanopartículas , Neoplasias da Mama/tratamento farmacológico , Linhagem Celular Tumoral , Doxorrubicina/farmacologia , Humanos , Hidrogéis , Metaloproteinases da Matriz
18.
Colloids Surf B Biointerfaces ; 203: 111733, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33862572

RESUMO

Chemotherapy-photodynamic therapy (PDT)-based combination therapy is a currently frequently used means in cancer treatment that photosensitizer was able to generate reactive oxygen species (ROS) for improving chemotherapy, owing to the high oxidative stress of the tumor microenvironment (TME). Whereas, cancer cells were accustomed to oxidative stress by overexpression of antioxidant such as glutathione (GSH), which would consume the damage of ROS, as well as it could result in ineffective treatment. Herein, amplification of oxidative stress preferentially in tumor cells by consuming GSH or generating ROS is a reasonable treatment strategy to develop anticancer drugs. To achieve excellent therapeutic effects, we designed a GSH-scavenging and ROS-generating polymeric micelle mPEG-S-S-PCL-Por (MSLP) for amplifying oxidative stress and enhanced anticancer therapy. The amphiphilic polymer of methoxy poly(ethylene glycol) (mPEG)-S-S-poly(ε-caprolactone) (PCL)-Protoporphyrin (Por) was self-assembled into polymeric micelles with the anticancer drug doxorubicin (DOX) for treatment and tracking via FRET. Spherical DOX/MSLP micelles with the average size of 88.76 ±â€¯3.52 nm was procured with negatively charged surface, reduction sensitivity and high drug loading content (17.47 ±â€¯1.53 %). The intracellular ROS detection showed that the MSLP could deplete glutathione and regenerate additional ROS. The cellular uptake of DOX/MSLP micelles was grabbed real-time monitoring by the Fluorescence resonance energy transfer (FRET) effect between DOX and MSLP. The reduction-sensitive polymeric micelles MSLP as amplifying oxidative stress vehicles combined chemotherapy and PDT exhibited significant antitumor activity both in vitro (IC50 = 0.041 µg/mL) and much better antitumor efficacy than that of mPEG-PCL-Por (MLP) micelles in vivo.


Assuntos
Antineoplásicos , Micelas , Antineoplásicos/farmacologia , Doxorrubicina/farmacologia , Estresse Oxidativo , Polietilenoglicóis , Polímeros
19.
Orphanet J Rare Dis ; 15(1): 150, 2020 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-32539862

RESUMO

BACKGROUND: Cystic fibrosis (CF) is a rare autosomal recessive disorder caused by biallelic mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene. The clinical features and mutation spectrum of CF have been well characterized in Caucasians, while limited studies were conducted in Chinese patients. SUBJECTS AND METHODS: A total of 20 individuals from 19 families were diagnosed with CF in this study. We analyzed the clinical features and screened all coding exons of CFTR using a combination of Sanger sequencing and multiplex ligation-dependent probe amplification analysis. RESULTS: The median age at onset was 9.3 years in our cohort, while the median age at diagnosis was 19 years. The respiratory system was most frequently affected in this study: all patients (100%, 19/19) presented diffuse bronchiectasis and 61.1% (11/18) of patients showed a forced expiratory volume in 1 s below 80% predicted. Six patients (6/20, 30%) exhibited allergic bronchopulmonary aspergillosis (ABPA). Only 4 (4/20, 20%) patients presented pancreatic exocrine insufficiency (PI). Three adult male patients receiving examinations for congenital bilateral absence of the vas deferens were all found positive for the condition. A total of 22 distinct mutations were detected in this cohort, with the variant p.G970D as the most common variant (12/38 alleles, 31.6%). Four variants (p.Y109D, p.I203F, p.D572E, and exon 2-3 deletion) were novel, which expanded the mutation spectrum of Chinese CF patients. CONCLUSIONS: Chinese CF patients showed different clinical features and a distinct CFTR mutation spectrum compared with Caucasians. There is a significant diagnosis delay, suggesting the current underdiagnosis of CF in China.


Assuntos
Fibrose Cística , Insuficiência Pancreática Exócrina , Adulto , China , Fibrose Cística/genética , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Éxons , Humanos , Masculino , Mutação/genética
20.
Front Microbiol ; 11: 705, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32362886

RESUMO

HpaR, a MarR family transcriptional regulator, was first identified in Escherichia coli W for its regulation of the hpa-meta operon. Little else is known regarding its functionality. Here, we report that in Yersinia pseudotuberculosis, HpaR negatively regulates the hpa-meta operon similar to in E. coli W. To investigate additional functions of HpaR, RNA sequencing was performed for both the wild-type and the ΔhpaR mutant, which revealed that the type VI secretion system (T6SS) was positively regulated by HpaR. T6SS4 is important for bacteria resisting environmental stress, especially oxidative stress. We demonstrate that HpaR facilitates bacteria resist oxidative stress by upregulating the expression of T6SS4 in Y. pseudotuberculosis. HpaR is also involved in biofilm formation, antibiotic resistance, adhesion to eukaryotic cells, and virulence in mice. These results greatly expand our knowledge of the functionality of HpaR and reveal a new pathway that regulates T6SS4.

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