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1.
J Nanobiotechnology ; 21(1): 484, 2023 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-38105186

RESUMO

Acute kidney injury (AKI) is a common kidney disease associated with excessive reactive oxygen species (ROS). Unfortunately, due to the low kidney targeting and undesired side effects, the existing antioxidant and anti-inflammatory drugs are unavailable for AKI management in clinic. Therefore, it's essential to develop effective nanodrugs with high renal targeting and biocompatibility for AKI treatment. Herein, we reported a novel nanodrug for AKI treatment, utilizing poly(ursolic acid) (PUA) as a bioactive nanocarrier and resveratrol (RES) as a model drug. The PUA polymer was synthesized form ursolic acid with intrinsic antioxidant and anti-inflammatory activities, and successfully encapsulated RES through a nanoprecipitation method. Subsequently, we systemically investigated the therapeutic potential of RES-loaded PUA nanoparticles (PUA NPs@RES) against AKI. In vitro results demonstrated that PUA NPs@RES effectively scavenged ROS and provided substantial protection against H2O2-induced cellular damage. In vivo studies revealed that PUA NPs significantly improved drug accumulation in the kidneys and exhibited favorable biocompatibility. Furthermore, PUA NPs alone exhibited additional anti-inflammatory and antioxidant effect, synergistically enhancing therapeutic efficacy in AKI mouse models when combined with RES. Overall, our study successfully developed an effective nanodrug using self-therapeutic nanocarriers, presenting a promising option for the treatment of AKI.


Assuntos
Injúria Renal Aguda , Nanopartículas , Animais , Camundongos , Resveratrol/farmacologia , Resveratrol/uso terapêutico , Antioxidantes/uso terapêutico , Ácido Ursólico , Espécies Reativas de Oxigênio , Polímeros/uso terapêutico , Peróxido de Hidrogênio , Injúria Renal Aguda/tratamento farmacológico , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico
2.
Chemistry ; 27(33): 8557-8563, 2021 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-33860567

RESUMO

This study demonstrates that chiral-at-iron complexes, in which all coordinated ligands are achiral and the overall chirality the consequence of a stereogenic iron center, are capable of catalyzing asymmetric transformations with very high enantioselectivities. The catalyst is based on a previously reported design (J. Am. Chem. Soc. 2017, 139, 4322), in which iron(II) is surrounded by two configurationally inert achiral bidentate N-(2-pyridyl)-substituted N-heterocyclic carbenes in a C2 -symmetric fashion and complemented by two labile acetonitriles. By replacing mesityl with more bulky 2,6-diisopropylphenyl substituents at the NHC ligands, the steric hindrance at the catalytic site was increased, thereby providing a markedly improved asymmetric induction. The new chiral-at-iron catalyst was applied to the inverse electron demand hetero-Diels-Alder reaction between ß,γ-unsaturated α-ketoester and enol ethers provide 3,4-dihydro-2H-pyrans in high yields with excellent diastereoselectivities (up to 99 : 1 dr) and excellent enantioselectivities (up to 98 % ee). Other electron rich dienophiles are also suitable as demonstrated for a reaction with a vinyl azide.

4.
J Am Chem Soc ; 140(15): 5146-5152, 2018 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-29577723

RESUMO

The origin of enantioselectivity in the asymmetric alkynylation of trihalomethyl ketones catalyzed by octahedral stereogenic-at-ruthenium complexes has been investigated through density functional theory calculations. Computational results support a mechanism involving formation of a ruthenium acetylide, followed by pre-coordination of the trihalomethyl ketone through the carbonyl oxygen and intramolecular attack of the acetylide via a compact four-membered transition state. Differences in computed free energies of activation for the formation of the major and minor propargyl alcohol enantiomers are in good agreement with the experimentally observed levels of asymmetric induction. Analysis of fragment distortion energies shows that disfavored transition states are destabilized due to the more severe distortion and loss of π-conjugation in the coordinated arylketone fragments. Examination of the different substitution patterns in the ketone substrate and the catalyst reveals the key steric factors that control the enantioselectivity. Finally, calculations indicate promising directions for the simplification of the catalyst scaffold while preserving the high levels of enantioselectivity of these alkynylation reactions.

5.
Front Surg ; 10: 1108699, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37009618

RESUMO

Background: The aim of this study was to assess the impact of preoperative chemotherapy on long-term survival (≥1 month) in patients with thymic epithelial tumors (TETs) and conditions suitable for chemotherapy using data from surveillance, epidemiology, and end-result databases. Methods: This retrospective study controlled for confounding factors by propensity score matching (PSM), analyzed overall survival (OS) and cancer-specific survival (CSS) by Kaplan-Meier methods, and analyzed factors affecting the prognosis of patients undergoing surgery for thymic epithelial tumors by univariate and multifactorial Cox regression. Results: A total of 2,451 patients who underwent surgery for TETs were identified from the Surveillance, Epidemiology, and End Results database. Preoperative chemotherapy significantly improved OS and CSS in patients with stage III/IV TETs compared to patients without preoperative chemotherapy. Subgroup analysis showed that patients younger than 60 years of age with TETs, patients with thymic carcinoma, and patients with TETs with multiple cancers were more likely to benefit from preoperative chemotherapy. Conclusion: This study found that preoperative chemotherapy is a viable option for advanced thymoma with favorable overall and cancer-specific survival rates, but patient history and physical condition should be fully considered in conjunction with diagnostic imaging findings to assess patient tolerance to chemotherapy.

6.
Kidney Int Rep ; 8(12): 2742-2753, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38106587

RESUMO

Introduction: Podocyte infolding glomerulopathy (PIG) is a newly recognized rare glomerular injury. The clinical significance and mechanism of this injury pattern remains unclear. Methods: We conducted a retrospective study of renal biopsies from January 2018 to December 2020 in Kingmed Diagnostics. The renal biopsy features and clinical data were reviewed. Laser scanning microdissection and mass spectrometry (LMD/MS) was conducted to analyze the potential mechanism. Results: A total of 116 (0.092%) out of 126,086 biopsies were diagnosed as PIG during the period. Of these, 89 (76.7%) cases were found to have PIG coexisting with immune-complex associated glomerulonephritis (IC-PIG) whereas 27 (23.3%) were identified as isolated PIG without immunoglobulin or complement deposition. Systemic lupus erythematosus (SLE), especially with membranous lupus nephritis (LN), was diagnosed in most (70.8%) IC-PIG cases. Of the isolated PIG cases, 51.9% had no known underlying conditions; however, a relatively high positive rate (42.1%) of antinuclear antibody (ANA) was detected. Nearly half (47.5%) of the patients presented with nephrotic syndrome (NS). PIG grade was associated with proteinuria in isolated PIG (P = 0.035). LMD/MS revealed dysregulated cytoskeletal protein α-actinin4 (ACTN4) and tubulin beta-4 chain in PIG compared with normal donor kidney and minimal change disease (MCD). The displacement of ACTN4 into the glomerular basement membrane (GBM) was confirmed by the confocal microscope. Conclusion: PIG is a rare podocyte injury that can exist alone without underlying disease or be concurrent with various diseases, especially SLE. Podocyte cytoskeletal protein ACTN4 and tubulin beta-4 chain were dysregulated, which may be involved in the mechanism of PIG.

7.
Front Immunol ; 13: 1045982, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36505444

RESUMO

Background: Along with uric acid, which is the primary driving factor of gout, downstream inflammatory mediators have been shown to be involved in the pathogenesis of gouty arthritis flares. Extracorporeal haemadsorption is an emerging technology for the treatment of dysregulated inflammatory states by effectively removing cytokines from the bloodstream. Whether haemadsorption was effective in refractory gout flares has not been reported in the literature. Case summary: We report the case of a 52-year-old male who presented with refractory gouty arthropathy for 30 years. His uric acid levels were poorly controlled due to poor diet and treatment compliance. Tophi were found to have precipitated in multiple joints and subcutaneous tissue. In the last 2 years, his incidents of gouty flares had become more frequent, and resistant to the medications, including colchicine, allopurinol, febuxostat, glucocorticoids, and NSAID analgesics. He had experienced a triad of chills, high fever and arthritis for the past 2 weeks. Therefore, he took 2 mg colchicine twice daily for 2 weeks with no improvement in his pain. Proinflammatory cytokines, such as interleukin-6 (IL-6) and tumour necrosis factor-α (TNF-α), were found to be remarkably elevated. Given that conventional treatment was unsuccessful, we tried to employ plasma adsorption (PA) to remove inflammatory cytokines. After 4 sessions, symptoms, such as fever, joint swelling and pain, were greatly improved. Meanwhile, the levels of proinflammatory factors such as IL-6 and TNF-α were found to be decreased, while the anti-inflammatory factor IL-10 remained the same during the course. He was followed up for 8 months and arthritis have flared up twice in response to a high-purine diet. Conclusion: Our study suggests that plasma adsorption (PA) may be a promising and feasible treatment for refractory gout when conventional treatments are unsatisfactory or contraindicated. However, more clinical trials are needed to verify the efficacy and safety of the treatment. Core tip: Chronic gouty arthritis flares are refractory to conventional treatment, such as uric acid-lowering drugs and NSAID analgesics. Due to the involvement of inflammatory cytokines, plasma adsorption was employed to alleviate flares by removing inflammatory mediators. Herein, we report a 52-year-old male who presented with refractory gouty arthropathy for 30 years, manifested with a triad of chills, high fever and arthritis. He underwent several sessions of plasma adsorption, and his symptoms soon improved, along with a drop in inflammatory mediators. We conclude that plasma adsorption may be a promising and feasible treatment for refractory gout when conventional treatments are unsatisfactory or contraindicated.


Assuntos
Artrite Gotosa , Gota , Masculino , Humanos , Pessoa de Meia-Idade , Artrite Gotosa/terapia , Ácido Úrico , Interleucina-6 , Fator de Necrose Tumoral alfa , Exacerbação dos Sintomas , Colchicina , Citocinas , Mediadores da Inflamação , Dor , Anti-Inflamatórios não Esteroides
8.
J Inflamm Res ; 14: 1901-1913, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34012288

RESUMO

BACKGROUND: The aggressive phenotype of fibroblast-like synoviocytes (FLSs) is essential in the synovitis and bone destruction in rheumatoid arthritis (RA). Punicalagin is a natural polyphenol extracted in pomegranate juice, which possesses antioxidant, anti-inflammatory and anti-tumor properties suggesting it may be a potent drug for RA therapy. However, there is paucity of information on its effect in RA. OBJECTIVE: To investigate the effects of punicalagin on synovial inflammation and bone destruction in RA. METHODS: FLSs were isolated from synovial tissue of RA patients. The mRNA levels were evaluated by quantitative real-time PCR. Western blot was used for protein level measurements. The secretion of pro-inflammatory cytokines and metalloproteinases (MMPs) was detected by ELISA assays. Edu staining assays were carried out to investigate the proliferation of FLSs. Cell migration was assessed by Boyden chambers, wound scratch assays and F-actin staining in vitro. The intracellular translocation of nuclear factor kappa B (NF-κB) was investigated using immunofluorescence. The effects of punicalagin in vivo were measured by using collagen-induced arthritis (CIA) mice. RESULTS: Punicalagin treatments significantly reduced the TNF-α induced expressions of pro-inflammatory cytokines (IL-1ß, IL-6, IL-8 and IL-17A) and MMPs (MMP-1 and MMP-13) of RA FLSs. Punicalagin also suppressed the proliferation and migration of RA FLSs. Moreover, punicalagin (50mg/kg/d) alleviated arthritis severity and bone destruction, and decreased serum IL-6 and TNF-α in CIA mice. Further mechanism studies indicated that punicalagin blocked NF-κB activation via suppressing phosphorylation of IKK and IkBα, and preventing the translocation of 65. CONCLUSION: Our findings suggested that punicalagin might be one of natural therapeutic compounds for relieving RA progress via suppressing FLSs inflammation and migration through modulating NF-κB pathways.

9.
Front Immunol ; 12: 592841, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33717071

RESUMO

It was previously published that single-nucleotide polymorphism rs2476601 (PTPN22 [protein tyrosine phosphatase non-receptor type 22]-C1858T) might be related to increased sensibility to Mycobacterium tuberculosis and M. leprae infection. However, the results were inconclusive despite a high degree of similarity between both parameters. Herein, we carried out this meta-analysis to systematically summarize and articulate the correlation between PTPN22-C1858T polymorphism and mycobacterial infection. The susceptibility of PTPN22-C1858T carriers with autoimmune conditions receiving immunosuppressive therapy to M. tuberculosis and M. leprae infection was determined. A systematic retrieval of studies on relevance of PTPN22-C1858T polymorphism to susceptibility of M. tuberculosis or M. leprae infection was performed in Chinese National Knowledge Infrastructure, PubMed and Embase databases. We regarded Odds ratios (ORs) and 95% confidence intervals (CIs) as the determined effect size. Finally, four and two case-control studies on tuberculosis and leprosy, respectively, were included. In all genetic models, without indicated association between PTPN22-C1858T polymorphism and tuberculosis's susceptibility. [C versus T: OR = 0.22 (95% CI: 0.09-0.50, PH = 0.887); CT versus CC: OR = 0.21 (95% CI: 0.09-0.49, PH = 0.889); TT+CT versus CC: OR = 0.21 (95% CI: 0.09-0.49, PH = 0.889)]. A significantly increased risk of leprosy was perceived in patients with the PTPN22-C1858T polymorphism [C versus T: OR = 2.82 (95% CI: 1.02-7.81, PH = 0.108)]. While the PTPN22-C1858T polymorphism is irrelevant to higher susceptibility to the infection of M. tuberculosis in Caucasians and Asians, it is relevant to increased susceptibility to the infection of M. leprae. However, the results of M. leprae are supposed to interpreted with prudence owing to the limited quantity of studies and heterogeneity. Further well-designed studies with sufficient populations are required to verify our conclusions.


Assuntos
Alelos , Predisposição Genética para Doença , Hanseníase/etiologia , Mycobacterium leprae , Mycobacterium tuberculosis , Polimorfismo de Nucleotídeo Único , Proteína Tirosina Fosfatase não Receptora Tipo 22/genética , Tuberculose/etiologia , Frequência do Gene , Estudos de Associação Genética , Genótipo , Humanos , Hanseníase/diagnóstico , Razão de Chances , Viés de Publicação , Risco , Tuberculose/diagnóstico
10.
Chem Sci ; 10(11): 3202-3207, 2019 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-30996902

RESUMO

The catalytic enantioselective intramolecular C(sp3)-H amination of aliphatic azides represents an efficient method for constructing chiral saturated cyclic amines which constitute a prominent structural motif in bioactive compounds. We report a dual catalytic system involving a chiral-at-metal bis(pyridyl-NHC) ruthenium complex and tris(4-fluorophenyl)phosphine (both 1 mol%), which facilitates the cyclization of aliphatic azides to chiral α-aryl pyrrolidines with enantioselectivities of up to 99% ee, including a pyrrolidine which can be converted to the anti-tumor alkaloid (R)-(+)-crispine. Mechanistically, the phosphine activates the organic azide to form an intermediate iminophosphorane and transfers the nitrene unit to the ruthenium providing an imido ruthenium intermediate which engages in the highly stereocontrolled C-H amination. This dual catalysis combines ruthenium catalysis with the Staudinger reaction and provides a novel strategy for catalyzing enantioselective C-H aminations of unactivated aliphatic azides.

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