Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 47
Filtrar
1.
Med Res Rev ; 44(4): 1545-1565, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38279970

RESUMO

Overexpression of the epidermal growth factor receptor (EGFR, erbB1) has been observed in a wide range of solid tumors and has frequently been associated with poor prognosis. As a result, EGFR inhibition has become an attractive anticancer drug design strategy, and a large number of small molecular inhibitors have been developed. Despite the widespread clinical use of EGFR tyrosine kinase inhibitors (TKIs), their drug resistance, inadequate accumulation in tumors, and severe side effects have spurred the search for better antitumor drugs. Metal complexes have attracted much attention because of their different mechanisms compared with EGFR-TKIs. Therefore, the combination of metals and inhibitors is a promising anticancer strategy. For example, Ru and Pt centers are introduced to design complexes with double or multiple targets, while Au complexes are combined with inhibitors to overcome drug resistance. Co complexes are designed as prodrugs with weak side effects and enhanced targeting by the hypoxia activation strategy, and other metals such as Rh and Fe enhance the anticancer effect of the complexes. In addition, the introduction of Ga center is beneficial to the development of nuclear imaging tracers. In this paper, metal EGFR-TKI complexes in the last 15 years are reviewed, their mechanisms are briefly introduced, and their advantages are summarized.


Assuntos
Antineoplásicos , Complexos de Coordenação , Receptores ErbB , Inibidores de Proteínas Quinases , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/metabolismo , Humanos , Antineoplásicos/farmacologia , Antineoplásicos/química , Ligantes , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/química , Complexos de Coordenação/química , Complexos de Coordenação/farmacologia , Animais , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo
2.
J Antimicrob Chemother ; 79(1): 27-35, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-37944030

RESUMO

BACKGROUND: The spread of antibiotic-resistant bacteria (ARB) and antibiotic resistance genes (ARGs) among humans and food-producing animals has been widely reported. However, the transmission routes and associated risk factors remain incompletely understood. METHODS: Here, we used commensal Escherichia coli bacteria strains from faeces of pigs and local citizens [HEG: high exposure group (pig breeders, butchers or restaurant chefs) and LEG: low exposure group (other occupations)] to explore the dynamics of ARB and ARG transmission between animals and humans. RESULTS: Most ARGs (96%) present in pigs were shared with humans. Carriage rates of the shared ARGs suggest two transmission patterns among pigs, the HEG and LEG: one pattern was highest in pigs, gradually decreasing in the HEG and LEG (e.g. floR and cmlA1); the other pattern was increasing from pigs to the HEG but then decreasing in the LEG (e.g. mcr-1.1). Carriage rates of the HEG were higher than in the LEG in both patterns, implicating the HEG as a crucial medium in transmitting ARB and ARGs between food-producing animals and humans. Moreover, frequent inter/intragroup transmission via strains, plasmids and/or mobile elements was evident. Carriage of mcr-1.1 on human-gut-prevalent plasmids possibly promoted its enrichment in the HEG. CONCLUSIONS: The HEG is a crucial factor in transmitting ARB and ARGs between food-producing animals and humans. Rational measures to contain the risks of occupational exposure are urgently needed to keep dissemination of antibiotic resistance in check and safeguard public health.


Assuntos
Genes Bacterianos , Exposição Ocupacional , Humanos , Suínos , Animais , Antagonistas de Receptores de Angiotensina , Inibidores da Enzima Conversora de Angiotensina , Resistência Microbiana a Medicamentos , Escherichia coli/genética , Antibacterianos/farmacologia
3.
J Autoimmun ; 146: 103214, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38648706

RESUMO

INTRODUCTION: Rheumatoid arthritis (RA) is a systemic inflammatory autoimmune disease characterized by joint inflammation and bone damage, that not only restricts patient activity but also tends to be accompanied by a series of complications, seriously affecting patient prognosis. Peroxisome proliferator-activated receptor gamma (PPARG), a receptor that controls cellular metabolism, regulates the function of immune cells and stromal cells. Previous studies have shown that PPARG is closely related to the regulation of inflammation. However, the role of PPARG in regulating the pathological processes of RA is poorly understood. MATERIALS AND METHODS: PPARG expression was examined in the synovial tissues and peripheral blood mononuclear cells (PBMCs) from RA patients and the paw of collagen-induced arthritis (CIA) model rats. Molecular biology experiments were designed to examine the effect of PPARG and cannabidiol (CBD) on RAW264.7 cells and CIA rats. RESULTS: The results reveal that PPARG accelerates reactive oxygen species (ROS) clearance by promoting autophagy, thereby inhibiting ROS-mediated macrophage polarization and NLRP3 inflammasome activation. Notably, CBD may be a promising candidate for understanding the mechanism by which PPARG regulates autophagy-mediated inflammation. CONCLUSIONS: Taken together, these findings indicate that PPARG may have a role for distinguishing between RA patients and healthy control, and for distinguishing RA activity; moreover, PPARG could be a novel pharmacological target for alleviating RA through the mediation of autophagy. CBD can act as a PPARG agonist that alleviates the inflammatory progression of RA.


Assuntos
Artrite Experimental , Artrite Reumatoide , Autofagia , Inflamação , PPAR gama , Espécies Reativas de Oxigênio , Animais , Feminino , Humanos , Masculino , Camundongos , Ratos , Artrite Experimental/imunologia , Artrite Experimental/metabolismo , Artrite Reumatoide/metabolismo , Artrite Reumatoide/imunologia , Autofagia/efeitos dos fármacos , Canabidiol/farmacologia , Modelos Animais de Doenças , Inflamassomos/metabolismo , Inflamação/metabolismo , Inflamação/imunologia , Leucócitos Mononucleares/metabolismo , Leucócitos Mononucleares/imunologia , Macrófagos/imunologia , Macrófagos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , PPAR gama/metabolismo , Células RAW 264.7 , Espécies Reativas de Oxigênio/metabolismo
4.
Angew Chem Int Ed Engl ; 63(12): e202319583, 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38282100

RESUMO

Small molecules, including therapeutic drugs and tracer molecules, play a vital role in biological processing, disease treatment and diagnosis, and have inspired various nanobiotechnology approaches to realize their biological function, particularly in drug delivery. Desirable features of a delivery system for functional small molecules (FSMs) include high biocompatibility, high loading capacity, and simple manufacturing processes, without the need for chemical modification of the FSM itself. Herein, we report a simple and versatile approach, based on metal-phenolic-mediated assembly, for assembling FSMs into nanoparticles (i.e., FSM-MPN NPs) under aqueous and ambient conditions. We demonstrate loading of anticancer drugs, latency reversal agents, and fluorophores at up to ~80 % that is mostly facilitated by π and hydrophobic interactions between the FSM and nanoparticle components. Secondary nanoparticle engineering involving coating with a polyphenol-antibody thin film or sequential co-loading of multiple FSMs enables cancer cell targeting and combination delivery, respectively. Incorporating fluorophores into FSM-MPN NPs enables the visualization of biodistribution at different time points, revealing that most of these NPs are retained in the kidney and heart 24 h post intravenous administration. This work provides a viable pathway for the rational design of small molecule nanoparticle delivery platforms for diverse biological applications.


Assuntos
Nanopartículas , Distribuição Tecidual , Nanopartículas/química , Sistemas de Liberação de Medicamentos , Fenóis , Polifenóis , Metais
5.
Pharmacol Res ; 187: 106556, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36403722

RESUMO

Traditional platinum-based anticancer drugs, led by cisplatin, play an important role in chemotherapy. However, the development of platinum compounds is limited due to serious toxicity and side effects. In recent years, studies have showed that immunogenic cell death (ICD) may be one of the potential action mechanisms of classical platinum drugs, such as oxaliplatin. This strategy combining chemotherapy and immunotherapy can effectively utilize the body's immune system to help platinum compounds to fight against tumors, and the dose can be appropriately reduced to limit toxic side effects. The induction of ICD by platinum compounds has become a research hotspot and one of the future development directions of metal drugs. Here, the progress of platinum compounds were collected and comprehensively summarized, their capacity of ICD induction and mechanism of action are exposed, providing reference for the design and synthesis of new anticancer platinum ICD inducers.


Assuntos
Antineoplásicos , Platina , Platina/farmacologia , Morte Celular Imunogênica , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Cisplatino/farmacologia , Compostos de Platina/farmacologia , Compostos de Platina/uso terapêutico
6.
Bioorg Chem ; 133: 106403, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36801790

RESUMO

Our previous studies suggested that N-phenyl aromatic amides are a class of promising xanthine oxidase (XO) inhibitor chemotypes. In this effort, several series of N-phenyl aromatic amide derivatives (4a-h, 5-9, 12i-w, 13n, 13o, 13r, 13s, 13t and 13u) were designed and synthesized to carry out an extensive structure-activity relationship (SAR). The investigation provided some valuable SAR information and identified N-(3-(1H-imidazol-1-yl)-4-((2-methylbenzyl)oxy)phenyl)-1H-imidazole-4-carboxamide (12r, IC50 = 0.028 µM) as the most potent XO inhibitor with close in vitro potency to that of topiroxostat (IC50 = 0.017 µM). Molecular docking and molecular dynamics simulation rationalized the binding affinity through a series of strong interactions with the residues Glu1261, Asn768, Thr1010, Arg880, Glu802, etc. In vivo hypouricemic studies also suggested that the uric acid lowering effect of compound 12r was improved compared with the lead g25 (30.61 % vs 22.4 % reduction in uric acid levels at 1 h; 25.91 % vs 21.7 % reduction in AUC of uric acid) . Pharmacokinetic studies revealed that compound 12r presented a short t1/2 of 0.25 h after oral administration. In addition, 12r has non-cytotoxicity against normal cell HK-2. This work may provide some insights for further development of novel amide-based XO inhibitors.


Assuntos
Radioisótopos de Nitrogênio , Xantina Oxidase , Amidas/farmacologia , Inibidores Enzimáticos/química , Simulação de Acoplamento Molecular , Estrutura Molecular , Relação Estrutura-Atividade , Ácido Úrico , Xantina Oxidase/antagonistas & inibidores
7.
Bioorg Med Chem Lett ; 60: 128582, 2022 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-35077850

RESUMO

A series of 4-(phenoxymethyl)-1H-1,2,3-triazole derivatives were designed, synthesized, and evaluated for their xanthine oxidase (XO) inhibitory activities. Among these compounds, 9m emerged as the most effective XO inhibitor with an IC50 value of 0.70 µM, which was approximately 14-fold more potent than allopurinol. Additionally, compound 9m displayed favorable drug-like properties with ligand efficiency (LE) and lipophilic ligand efficiency (LLE) values of 0.33 and 3.41, respectively. We further explored the binding mode of 9m in complex with XO by molecular docking and molecular dynamics studies. In vivo hypouricemic studies also suggested that 9m could effectively lower the serum uric acid levels of rat. In summary, compound 9m could be a promising lead for further development of XO inhibitors.


Assuntos
Descoberta de Drogas , Inibidores Enzimáticos/farmacologia , Triazóis/farmacologia , Xantina Oxidase/antagonistas & inibidores , Animais , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Hiperuricemia/induzido quimicamente , Hiperuricemia/tratamento farmacológico , Hiperuricemia/metabolismo , Ligantes , Modelos Moleculares , Estrutura Molecular , Ácido Oxônico , Ratos , Relação Estrutura-Atividade , Triazóis/síntese química , Triazóis/química , Ácido Úrico/antagonistas & inibidores , Ácido Úrico/sangue , Xantina Oxidase/metabolismo
8.
Bioorg Chem ; 127: 105938, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35752100

RESUMO

Xanthine oxidase (XO) is a flavoprotein that exists in various organisms and can catalyze the uric acid formation in the human body. Based on the amide framework of N-(4-((3-cyanobenzyl)oxy)-3-(1H-tetrazol-1-yl)phenyl)isonicotinamide (compound 1) reported in our previous work, a series of N-(4-alkoxy-3-(1H-tetrazol-1-yl)phenyl) heterocyclic aromatic amide derivatives were designed, synthesized and evaluated as novel amide-based XO inhibitors. Structure-activity relationship campaign identified the most promising compound g25 (IC50 = 0.022 µM), which possesses a special 1H-imidazole-5-carboxamide scaffold and presented comparable XO inhibitory potency to topiroxostat (IC50 = 0.017 µM). Enzyme kinetic studies revealed that compound g25 acted as a mixed-type XO inhibitor. Molecular docking and molecular dynamics indicated that imidazole NH of g25 formed two stable hydrogen bonds with Glu1261 residue of XO that provided a vital contribution for the binding affinity. In addition, in vivo activity evaluation demonstrated that compound g25 exhibited obviously hypouricemic effect on a potassium oxonate induced hyperuricemic rat model.


Assuntos
Amidas , Xantina Oxidase , Álcoois , Amidas/farmacologia , Animais , Desenho de Fármacos , Inibidores Enzimáticos/química , Humanos , Imidazóis/farmacologia , Cinética , Simulação de Acoplamento Molecular , Estrutura Molecular , Ratos , Relação Estrutura-Atividade
9.
Bioorg Chem ; 128: 106064, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35987190

RESUMO

Xanthine oxidase (XO) inhibitors are widely used in the control of serum uric acid levels in the clinical management of gout. Our continuous efforts in searching novel amide-based XO inhibitors culminated in the identification of N-(4-((3-cyanobenzyl)oxy)-3-(1H-tetrazol-1-yl)phenyl)isonicotinamide (TS10), which exhibited comparable in vitro inhibition to that of topiroxostat (TS10, IC50 = 0.031 µM; topiroxostat, IC50 = 0.020 µM). According to the molecular modeling, we speculated that, as well as topiroxostat, TS10 would be biotransformed by XO to yield TS10-2-OH. In this work, TS10-2-OH was successfully identified in XO targeted metabolism study, demonstrated that TS10 underwent a covalent binding with XO via a TS10-O-Mo intermediate after anchoring in the XO molybdenum cofactor pocket. Furthermore, TS10-2-OH is a weak active metabolite, and its potency was explained by the molecular docking. In metabolites identification, TS10 could be oxidized by CYP2C9, CYP3A4 and CYP3A5 to generate two mono-hydroxylated metabolites (not TS10-2-OH); and could occur degradation in plasma to mainly generate a hydrolytic metabolite (TS10-hydrolysate). In pharmacokinetic assessment, the low oral system exposure was observed (Cmax = 14.73 ± 2.66 ng/mL and AUClast = 9.17 ± 1.42 h⋅ng/mL), which could be explained by the poor oral absorption property found in excretion studies. Nonetheless, in pharmacodynamic evaluation, TS10 exhibited significant uric acid-lowering effect after oral administration in a dose-dependent manner. Briefly, in addition to allopurinol and topiroxostat, TS10 is possibly another explicitly mechanism-based XO inhibitor with powerful covalent inhibition.


Assuntos
Ácido Úrico , Xantina Oxidase , Alopurinol/farmacologia , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Simulação de Acoplamento Molecular , Xantina Oxidase/metabolismo
10.
Clin Sci (Lond) ; 135(20): 2357-2376, 2021 10 29.
Artigo em Inglês | MEDLINE | ID: mdl-34661658

RESUMO

Ophthalmology has been one of the early adopters of artificial intelligence (AI) within the medical field. Deep learning (DL), in particular, has garnered significant attention due to the availability of large amounts of data and digitized ocular images. Currently, AI in Ophthalmology is mainly focused on improving disease classification and supporting decision-making when treating ophthalmic diseases such as diabetic retinopathy, age-related macular degeneration (AMD), glaucoma and retinopathy of prematurity (ROP). However, most of the DL systems (DLSs) developed thus far remain in the research stage and only a handful are able to achieve clinical translation. This phenomenon is due to a combination of factors including concerns over security and privacy, poor generalizability, trust and explainability issues, unfavorable end-user perceptions and uncertain economic value. Overcoming this challenge would require a combination approach. Firstly, emerging techniques such as federated learning (FL), generative adversarial networks (GANs), autonomous AI and blockchain will be playing an increasingly critical role to enhance privacy, collaboration and DLS performance. Next, compliance to reporting and regulatory guidelines, such as CONSORT-AI and STARD-AI, will be required to in order to improve transparency, minimize abuse and ensure reproducibility. Thirdly, frameworks will be required to obtain patient consent, perform ethical assessment and evaluate end-user perception. Lastly, proper health economic assessment (HEA) must be performed to provide financial visibility during the early phases of DLS development. This is necessary to manage resources prudently and guide the development of DLS.


Assuntos
Pesquisa Biomédica , Aprendizado Profundo , Oftalmopatias , Oftalmologia , Animais , Tomada de Decisão Clínica , Técnicas de Apoio para a Decisão , Diagnóstico por Computador , Difusão de Inovações , Oftalmopatias/diagnóstico , Oftalmopatias/epidemiologia , Oftalmopatias/fisiopatologia , Oftalmopatias/terapia , Humanos , Prognóstico , Reprodutibilidade dos Testes
11.
Curr Opin Ophthalmol ; 32(5): 459-467, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34324454

RESUMO

PURPOSE OF REVIEW: The development of deep learning (DL) systems requires a large amount of data, which may be limited by costs, protection of patient information and low prevalence of some conditions. Recent developments in artificial intelligence techniques have provided an innovative alternative to this challenge via the synthesis of biomedical images within a DL framework known as generative adversarial networks (GANs). This paper aims to introduce how GANs can be deployed for image synthesis in ophthalmology and to discuss the potential applications of GANs-produced images. RECENT FINDINGS: Image synthesis is the most relevant function of GANs to the medical field, and it has been widely used for generating 'new' medical images of various modalities. In ophthalmology, GANs have mainly been utilized for augmenting classification and predictive tasks, by synthesizing fundus images and optical coherence tomography images with and without pathologies such as age-related macular degeneration and diabetic retinopathy. Despite their ability to generate high-resolution images, the development of GANs remains data intensive, and there is a lack of consensus on how best to evaluate the outputs produced by GANs. SUMMARY: Although the problem of artificial biomedical data generation is of great interest, image synthesis by GANs represents an innovation with yet unclear relevance for ophthalmology.


Assuntos
Aprendizado Profundo , Processamento de Imagem Assistida por Computador , Redes Neurais de Computação , Oftalmologia , Inteligência Artificial , Humanos , Processamento de Imagem Assistida por Computador/métodos
12.
Bioorg Chem ; 117: 105417, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34673452

RESUMO

Our previous work identified a promising isonicotinamide based xanthine oxidase (XO) inhibitor, N-(3-cyano-4-((2-cyanobenzyl)oxy)phenyl)isonicotinamide (1), and concluded that amide is an effective linker in exploring the XO inhibitor chemical space that is completely different from the five-membered ring framework of febuxostat and topiroxostat. Indole, an endogenous bioactive substance and a popular drug construction fragment, was involved in the structural optimization campaign of the present effort. After the installation of some functional groups, N-(1-alkyl-3-cyano-1H-indol-5-yl) was generated and employed to mend the missing H-bond interaction between the 3'-cyano of 1 and Asn768 residue of XO by shortening their distance. In this context, eight kinds of heterocyclic aromatic amide chemotypes were rationally designed and synthesized to investigate the structure-activity relationship (SAR) of amide-based XO inhibitors. The optimized compound a6 (IC50 = 0.018 µM) exhibits 17.2-fold improved potency than the initial compound 1 (IC50 = 0.31 µM). Its potency is comparable to that of topiroxostat (IC50 = 0.013 µM). Molecular docking and molecular dynamics studies proved the existence of the stable H-bond between the cyano group and the Asn768 residue. Moreover, oral administration of a6 (11.8 mg/kg) could effectively reduce serum uric acid levels in an acute hyperuricemia rat model. Liver microsomal stability assay illustrated that compound a6 possesses well metabolic stability in rat liver microsomes. However, the in vivo potency of a6 was much lower than that of topiroxostat, which may be explained by the poor absorption found in the parallel artificial membrane permeability assay (PAMPA). In addition, 6a has non-cytotoxicity against normal cell lines MCF10A and 16HBE. Taken together, this work culminated in the identification of compound 6a as an excellent lead for further exploration of amide-based XO inhibitors.


Assuntos
Amidas/farmacologia , Desenho de Fármacos , Inibidores Enzimáticos/farmacologia , Indóis/farmacologia , Xantina Oxidase/antagonistas & inibidores , Amidas/química , Amidas/metabolismo , Animais , Bovinos , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/química , Inibidores Enzimáticos/metabolismo , Feminino , Indóis/química , Masculino , Microssomos Hepáticos/química , Microssomos Hepáticos/metabolismo , Leite/enzimologia , Modelos Moleculares , Estrutura Molecular , Ratos , Ratos Sprague-Dawley , Relação Estrutura-Atividade , Xantina Oxidase/metabolismo
13.
Angew Chem Int Ed Engl ; 60(5): 2594-2598, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-33089613

RESUMO

Using the DNA origami technique, we constructed a DNA nanodevice functionalized with small interfering RNA (siRNA) within its inner cavity and the chemotherapeutic drug doxorubicin (DOX), intercalated in the DNA duplexes. The incorporation of disulfide bonds allows the triggered mechanical opening and release of siRNA in response to intracellular glutathione (GSH) in tumors to knockdown genes key to cancer progression. Combining RNA interference and chemotherapy, the nanodevice induced potent cytotoxicity and tumor growth inhibition, without observable systematic toxicity. Given its autonomous behavior, exceptional designability, potent antitumor activity and marked biocompatibility, this DNA nanodevice represents a promising strategy for precise drug design for cancer therapy.


Assuntos
Terapia Combinada/métodos , DNA/química , Nanopartículas/química , Neoplasias/tratamento farmacológico , Sistemas de Liberação de Medicamentos , Humanos
14.
Curr Opin Ophthalmol ; 31(5): 351-356, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32740068

RESUMO

PURPOSE OF REVIEW: The use of artificial intelligence (AI) in ophthalmology has increased dramatically. However, interpretation of these studies can be a daunting prospect for the ophthalmologist without a background in computer or data science. This review aims to share some practical considerations for interpretation of AI studies in ophthalmology. RECENT FINDINGS: It can be easy to get lost in the technical details of studies involving AI. Nevertheless, it is important for clinicians to remember that the fundamental questions in interpreting these studies remain unchanged - What does this study show, and how does this affect my patients? Being guided by familiar principles like study purpose, impact, validity, and generalizability, these studies become more accessible to the ophthalmologist. Although it may not be necessary for nondomain experts to understand the exact AI technical details, we explain some broad concepts in relation to AI technical architecture and dataset management. SUMMARY: The expansion of AI into healthcare and ophthalmology is here to stay. AI systems have made the transition from bench to bedside, and are already being applied to patient care. In this context, 'AI education' is crucial for ophthalmologists to be confident in interpretation and translation of new developments in this field to their own clinical practice.


Assuntos
Inteligência Artificial , Interpretação Estatística de Dados , Oftalmologistas , Atenção à Saúde , Humanos , Oftalmologia/métodos
15.
Ann Stat ; 42(6): 2164-2201, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25544785

RESUMO

We provide theoretical analysis of the statistical and computational properties of penalized M-estimators that can be formulated as the solution to a possibly nonconvex optimization problem. Many important estimators fall in this category, including least squares regression with nonconvex regularization, generalized linear models with nonconvex regularization and sparse elliptical random design regression. For these problems, it is intractable to calculate the global solution due to the nonconvex formulation. In this paper, we propose an approximate regularization path-following method for solving a variety of learning problems with nonconvex objective functions. Under a unified analytic framework, we simultaneously provide explicit statistical and computational rates of convergence for any local solution attained by the algorithm. Computationally, our algorithm attains a global geometric rate of convergence for calculating the full regularization path, which is optimal among all first-order algorithms. Unlike most existing methods that only attain geometric rates of convergence for one single regularization parameter, our algorithm calculates the full regularization path with the same iteration complexity. In particular, we provide a refined iteration complexity bound to sharply characterize the performance of each stage along the regularization path. Statistically, we provide sharp sample complexity analysis for all the approximate local solutions along the regularization path. In particular, our analysis improves upon existing results by providing a more refined sample complexity bound as well as an exact support recovery result for the final estimator. These results show that the final estimator attains an oracle statistical property due to the usage of nonconvex penalty.

16.
Front Physiol ; 15: 1391394, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38784117

RESUMO

Background: Evidence suggests that functional training (FT) positively impacts physical fitness and sports performance. However, a systematic review addressing the effects of FT on basketball players remains absent. This systematic review aims to explore the influence of FT on physical fitness and skill-related performance in basketball players. Methods: We searched six databases: Web of Science, Scopus, PubMed, China National Knowledge Infrastructure (CNKI), EBSCOhost, and Google Scholar. The search utilized a combination of keywords related to FT, physical fitness, and basketball. The Eligibility Criteria of Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA 2020) guidelines were followed in this systematic review. Results: 11 studies were ultimately included in this review, collectively recruiting 333 basketball players. These studies demonstrated that FT significantly improved muscle strength, linear speed, cardiovascular endurance, flexibility, balance, and muscular endurance. However, the effects of FT on power, change-of-direction speed, and basketball-related performance were inconsistent. Most studies showed FT significantly improves these three variables, but a small number of studies did not find positive effects of FT using specific tests including standing long jump, Sargent jump, touch high, lane agility, lateral shuffle, dribbling line drill, and free-throw tests. Conclusion: FT is an effective training method for enhancing physical fitness including muscle strength, linear speed, cardiovascular endurance, flexibility, balance, and muscular endurance. However, the effects of FT on power, change-of-direction speed, and basketball-related performance were divergent. Some tests were not improved after FT potentially due to the short program lengths and training session durations, varied athletic levels of players examined, and different foci of the FT exercises administered. The collective evidence suggests FT programs, especially the specific exercises prescribed, should be tailored to the desired training objectives. More studies investigating the effects of FT on physical fitness and basketball-related performance with established tests are encouraged in the future to expand the current evidence base. Systematic Review Registration: https://inplasy.com/, Identifier INPLASY202360072.

17.
IEEE Trans Pattern Anal Mach Intell ; 46(2): 1199-1211, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37903051

RESUMO

Offline reinforcement learning (RL) harnesses the power of massive datasets for resolving sequential decision problems. Most existing papers only discuss defending against out-of-distribution (OOD) actions while we investigate a broader issue, the false correlations between epistemic uncertainty and decision-making, an essential factor that causes suboptimality. In this paper, we propose falSe COrrelation REduction (SCORE) for offline RL, a practically effective and theoretically provable algorithm. We empirically show that SCORE achieves the SoTA performance with 3.1x acceleration on various tasks in a standard benchmark (D4RL). The proposed algorithm introduces an annealing behavior cloning regularizer to help produce a high-quality estimation of uncertainty which is critical for eliminating false correlations from suboptimality. Theoretically, we justify the rationality of the proposed method and prove its convergence to the optimal policy with a sublinear rate under mild assumptions.

18.
J Med Chem ; 67(3): 1982-2003, 2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38261008

RESUMO

Induction of immunogenic cell death (ICD) and activation of the cyclic GMP-AMP synthase stimulator of interferon gene (cGAS-STING) pathway are two potent anticancer immunotherapeutic strategies in hepatocellular carcinoma (HCC). Herein, 12 liver- and mitochondria-targeting gold(I) complexes (9a-9l) were designed and synthesized. The superior complex 9b produced a considerable amount of reactive oxygen species (ROS) and facilitated DNA excretion, the ROS-induced ICD and DNA activated the cGAS-STING pathway, both of which evoked an intense anticancer immune response in vitro and in vivo. Importantly, 9b strongly inhibited tumor growth in a patient-derived xenograft model of HCC. Overall, we present the first case of simultaneous ICD induction and cGAS-STING pathway activation within the same gold-based small molecule, which may provide an innovative strategy for designing chemoimmunotherapies for HCC.


Assuntos
Carcinoma Hepatocelular , Ouro , Morte Celular Imunogênica , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/tratamento farmacológico , DNA/metabolismo , Morte Celular Imunogênica/efeitos dos fármacos , Imunoterapia , Interferons , Neoplasias Hepáticas/tratamento farmacológico , Mitocôndrias/metabolismo , Nucleotidiltransferases/metabolismo , Espécies Reativas de Oxigênio , Transdução de Sinais , Ouro/farmacologia , Ouro/uso terapêutico , Nanopartículas Metálicas/química , Nanopartículas Metálicas/uso terapêutico
19.
Int Immunopharmacol ; 130: 111795, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38447418

RESUMO

Treg cell-based therapy has exhibited promising efficacy in combatting rheumatoid arthritis (RA). Dihydroartemisinin (DHA) exerts broad immunomodulatory effects across various diseases, with its recent spotlight on T-cell regulation in autoimmune conditions. The modulation of DHA on Treg cells and its therapeutic role in RA has yet to be fully elucidated. This study seeks to unveil the influence of DHA on Treg cells in RA and furnish innovative substantiation for the potential of DHA to ameliorate RA. To this end, we initially scrutinized the impact of DHA-modulated Treg cells on osteoclast (OC) formation in vitro using Treg cell-bone marrow-derived monocyte (BMM) coculture systems. Subsequently, employing the collagen-induced arthritis (CIA) rat model, we validated the efficacy of DHA and probed its influence on Treg cells in the spleen and popliteal lymph nodes (PLN). Finally, leveraging deep proteomic analysis with data-independent acquisition (DIA) and parallel accumulation-serial fragmentation (PASEF) technology, we found the alterations in the Treg cell proteome in PLN by proteomic analysis. Our findings indicate that DHA augmented suppressive Treg cells, thereby impeding OC formation in vitro. Consistently, DHA mitigated erosive joint destruction and osteoclastogenesis by replenishing splenic and joint-draining lymph node Treg cells in CIA rats. Notably, DHA induced alterations in the Treg cell proteome in PLN, manifesting distinct upregulation of alloantigen Col2a1 (Type II collagen alfa 1 chain) and CD8a (T-cell surface glycoprotein CD8 alpha chain) in Treg cells, signifying DHA's targeted modulation of Treg cells, rendering them more adept at sustaining immune tolerance and impeding bone erosion. These results unveil a novel facet of DHA in the treatment of RA.


Assuntos
Artemisininas , Artrite Experimental , Artrite Reumatoide , Osteólise , Ratos , Animais , Linfócitos T Reguladores , Proteoma , Proteômica , Articulações/patologia , Osteólise/metabolismo
20.
Front Med (Lausanne) ; 10: 1087123, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36760400

RESUMO

Caveolin-1 (Cav-1) is an integral scaffolding membrane protein found in most cell types. Cav-1 has been found to contribute significantly to ocular function, with mutations of Cav-1 being associated with a genetic risk of glaucoma development. Raised intraocular pressure (IOP) is a major modifiable risk factor for glaucoma. Cav-1 may be involved in both IOP-dependent and independent mechanisms involving vascular dysregulation. Systemic vascular diseases including hypertension, diabetes and hyperlipidaemia, have been shown to be associated with glaucoma development. Cav-1 is closely interlinked with endothelial nitric oxide synthase pathways that mediate vascular function and prevent cardiovascular diseases. Endothelial nitric oxide synthase and endothelin-1 are key vasoactive molecules expressed in retinal blood vessels that function to autoregulate ocular blood flow (OBF). Disruptions in the homeostasis of OBF have led to a growing concept of impaired neurovascular coupling in glaucoma. The imbalance between perfusion and neuronal stimulation arising from Cav-1 depletion may result in relative ischemia of the optic nerve head and glaucomatous injury. OBF is also governed by circadian variation in IOP and systemic blood pressure (BP). Cav-1 has been shown to influence central BP variability and other circadian rhythms such as the diurnal phagolysosomal digestion of photoreceptor fragments and toxic substrates to maintain ocular health. Overall, the vast implications of Cav-1 on various ocular mechanisms leading to glaucoma suggest a potential for new therapeutics to enhance Cav-1 expression, which has seen success in other neurodegenerative diseases.

SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa