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1.
J Asian Nat Prod Res ; 26(8): 993-1000, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38629616

RESUMO

A new 14-membered resorcylic acid lactone (RAL14), chaetolactone A (1), along with three known ones (2-4), was obtained from the fermentation of the soil-derived fungus Chaetosphaeronema sp. SSJZ001. Their structures were established based on extensive spectroscopic data analyses (UV, IR, HRESIMS, 1D, and 2D NMR),13C NMR chemical shifts calculations coupled with the DP4+ probability method, theoretical calculations of ECD spectra, as well as X-ray diffraction analysis. All compounds were evaluated for their cytotoxic effects against A549, HO-8910, and MCF-7 cell lines.


Assuntos
Ascomicetos , Lactonas , Lactonas/química , Lactonas/farmacologia , Lactonas/isolamento & purificação , Ascomicetos/química , Estrutura Molecular , Humanos , Ensaios de Seleção de Medicamentos Antitumorais , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Células MCF-7 , Cristalografia por Raios X , Ressonância Magnética Nuclear Biomolecular
2.
Front Microbiol ; 15: 1343763, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38389539

RESUMO

Background: Previous researches have suggested a significant connection between the gut microbiota/immune cells and morphine tolerance (MT), but there is still uncertainty regarding their causal relationship. Hence, our objective is to inverstigate this causal association and reveal the impact of gut microbiota/immune cells on the risk of developing MT using a two-sample Mendelian randomization (MR) study. Methods: We conducted a comprehensive analysis using genome-wide association study (GWAS) summary statistics for gut microbiota, immune cells, and MT. The main approach employed was the inverse variance-weighted (IVW) method in MR. To assess horizontal pleiotropy and remove outlier single-nucleotide polymorphisms (SNPs), we utilized the Mendelian randomization pleiotropy residual sum and outlier (MR-PRESSO) technique as well as MR-Egger regression. Heterogeneity detection was performed using Cochran's Q-test. Additionally, leave-one-out analysis was carried out to determine if any single SNP drove the causal association signals. Finally, we conducted a reverse MR to evaluate the potential of reverse causation. Results: We discovered that 6 gut microbial taxa and 16 immune cells were causally related to MT (p < 0.05). Among them, 2 bacterial features and 9 immunophenotypes retained a strong causal relationship with lower risk of MT: genus. Lachnospiraceae NK4A136group (OR: 0.962, 95% CI: 0.940-0.987, p = 0.030), genus. RuminococcaceaeUCG011 (OR: 0.960, 95% CI: 0.946-0.976, p = 0.003), BAFF-R on B cell (OR: 0.972, 95% CI: 0.947-0.998, p = 0.013). Furthermore, 4 bacterial features and 7 immunophenotypes were identified to be significantly associated with MT risk: genus. Flavonifractor (OR: 1.044, 95% CI: 1.017-1.069, p = 0.029), genus. Prevotella9 (OR: 1.054, 95% CI: 1.020-1.090, p = 0.037), B cell % CD3-lymphocyte (OR: 1.976, 95% CI: 1.027-1.129, p = 0.026). The Cochrane's Q test revealed no heterogeneity (p > 0.05). Furthermore, the MR-Egger and MR-PRESSO analyses reveal no instances of horizontal pleiotropy (p > 0.05). Besides, leave-one-out analysis confirmed the robustness of MR results. After adding BMI to the multivariate MR analysis, the gut microbial taxa and immune cells exposure-outcome effect were attenuated. Conclusion: Our research confirm the potential link between gut microbiota and immune cells with MT, shedding light on the mechanism by which gut microbiota and immune cells may contribute to MT. These findings lay the groundwork for future investigations into targeted prevention strategies.

3.
Org Lett ; 25(1): 200-204, 2023 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-36546845

RESUMO

A Lewis acid mediated conjugate addition of isocyanides to ß-hydroxy-α-diazo carbonyls has been developed for the first time. The reaction realizes the efficient construction of quaternary carbon centers and provides a novel and efficient strategy for the synthesis of ß-carboxamido-α-diazo carbonyls that would be otherwise difficult to form in a single step. Further applications, including synthesis of methylenecyclohexane, spiro-ß-lactam, and nitrogen-bridged tricyclic ß-lactam, demonstrated the tremendous potential of the coupling reaction.

4.
J Org Chem ; 87(24): 16604-16616, 2022 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-36469572

RESUMO

A photocatalyst-free radical cleavage of α-diazo sulfonium salts has been developed for the first time. The reaction provides an efficient method for the generation of diazomethyl radicals from α-diazosulfonium triflates under photochemical conditions. Utilizing the in situ generated diazomethyl radicals as key intermediate, the coupling cyclization reaction of α-diazosulfonium triflates with α-oxocarboxylic acids or alkynes has been achieved. The method affords a diverse set of important 2,5-disubstituted 1,3,4-oxadiazoles and 3,5-disubstituted-1H-pyrazoles with excellent regioselectivity in a single step. A reaction mechanism involving a radical pathway was further supported by control experiments and DFT calculations.

5.
Int J Biol Macromol ; 223(Pt A): 1443-1449, 2022 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-36379284

RESUMO

To study the effects of cooking methods on the structure and digestion changes of starch encapsulated by cellular structure, intact potato parenchyma cells were successfully isolated and then subjected to different domestic cooking methods, including baking, frying, boiling, and autoclaving. The morphology, crystalline structure, thermal properties, and in vitro starch digestibility of cooked cell samples were investigated. Our results indicated that potato cell walls remained intact and performed as physical barriers preventing the diffusion/absorption of α-amylase to intracellular starch substrates after baking or frying treatment. However, boiling or autoclaving treatment destroyed cell wall structure, and the disrupted cellular structure reduced the digestion rate, likely by inhibiting diffusion of amylase through a weakened cell wall barrier, but could not lower the final digestion extent when compared to the pure starch. These findings suggested that potato products with lower glycemic index can be obtained by baking or frying treatment.


Assuntos
Solanum tuberosum , Amido , Amido/química , Solanum tuberosum/química , Digestão , Culinária/métodos , Índice Glicêmico
6.
Cancers (Basel) ; 14(21)2022 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-36358669

RESUMO

Hyperthermia is being used as a radio- and chemotherapy sensitizer for a growing range of tumor subtypes in the clinic. Its potential is limited, however, by the ability of cancer cells to activate a protective mechanism known as the heat stress response (HSR). The HSR is marked by the rapid overexpression of molecular chaperones, and recent advances in drug development make their inhibition an attractive option to improve the efficacy of hyperthermia-based therapies. Our previous in vitro work showed that a single, short co-treatment with a HSR (HSP90) inhibitor ganetespib prolongs and potentiates the effects of hyperthermia on DNA repair, enhances hyperthermic sensitization to radio- and chemotherapeutic agents, and reduces thermotolerance. In the current study, we first validated these results using an extended panel of cell lines and more robust methodology. Next, we examined the effects of hyperthermia and ganetespib on global proteome changes. Finally, we evaluated the potential of ganetespib to boost the efficacy of thermo-chemotherapy and thermo-radiotherapy in a xenograft murine model of cervix cancer. Our results revealed new insights into the effects of HSR inhibition on cellular responses to heat and show that ganetespib could be employed to increase the efficacy of hyperthermia when combined with radiation.

9.
J Org Chem ; 87(5): 3156-3166, 2022 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-35156372

RESUMO

A NaN(SiMe3)2/CsTFA copromoted aminobenzylation/cyclization reaction of 2-isocyanobenzaldehydes with toluene derivatives or benzyl compounds has been developed. The reaction works with a broad range of toluene derivatives and benzyl compounds, and provides a simple and efficient strategy for the synthesis of 4-benzyl-substitued dihydroquinazoline and quinazoline derivatives from easily available acyclic starting materials in a single step. Further applications, including synthesis of quinazoline, dihydroindolo[1,2-c]quinazoline, and dihydro-8H-isoquinolino[2,3-c]quinazoline, demonstrated the tremendous potential of the tandem reaction.

10.
Bioengineered ; 12(2): 9401-9410, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34854364

RESUMO

Morphine tolerance poses a great challenge for clinicians, whose pathogenesis has a close connection with microglial activation and neuroinflammation. Dihydroartemisinin (DHA) that derives from artemisinin, may serve as a potential anti-inflammatory drug. In this study, the effects as well as the underlying mechanism of DHA on suppressing microglial activation and neuroinflammation were explored. The microglial cell line BV-2 cells were induced by morphine and treated with DHA or minocycline. With the application of CCK-8, the cell viability was detected. Western blot was employed to assess the expressions of Ki67, IBa-1, and TLR4 and quantitative real-time PCR (qRT-PCR) was adopted to evaluate miRNA-16 (miR-16) expression. With the adoption of ELISA kits and qRT-PCR, the release of inflammatory cytokines was evaluated. Besides, luciferase reporter assay was applied to testify the binding relationship between miR-16 and TLR4. NF-κB expression was measured by immunofluorescence. DHA reduced cell viability and decreased protein expression of Ki67 and IBa-1 in morphine-induced BV-2 cells. Additionally, DHA contributed to the declined release of pro-inflammatory cytokines. miR-16 was down-regulated by morphine but was up-regulated by DHA concentration-dependently in BV-2 cells. The inhibition of miR-16 partly abolished the inhibitory effects of DHA on morphine-induced microglial activation and neuroinflammation. Moreover, TLR4 was found to be bound to miR-16, and the inhibitory effect of DHA on TLR4/NF-κB was partly reversed by miR-16 inhibition. In conclusion, DHA remarkably suppressed microglial activation and neuroinflammation through regulating miR-16-mediated TLR4/NF-κB signaling. This study may provide a new solution to improve clinical analgesic efficacy of morphine.


Assuntos
Artemisininas/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Microglia/metabolismo , Morfina/efeitos adversos , Proteínas do Tecido Nervoso/biossíntese , Animais , Linhagem Celular , Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Camundongos , Morfina/farmacologia
11.
J Orthop Translat ; 31: 20-25, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34760621

RESUMO

BACKGROUND: Interruption of blood supply will lead to necrosis of body tissues, such as osteonecrosis of femoral head (ONFH). Vascularization has always been regarded as one of the biggest challenges in tissue engineering. In the current study, a novel device was proposed to reconstruct blood supply of necrotic femoral head. METHODS: Cryo-insult with liquid nitrogen method was adopted to establish the ONFH model. In experimental group, a novel scaffold carrying vascular bundle was implanted into the necrotic femoral head after decompression and the transplanted vascular bundles were anastomosed with the existing blood vessels around the hip. In control group, a traditional porous scaffold was inserted alone without vessels. Feasibility of this strategy was verified by animal experiments. Micro-CT analysis and histological evaluation were performed to investigate its preliminary efficacy. RESULTS: Feasibility of this innovative treatment strategy had been successfully verified in animal experiments. In the area of necrosis repair, more bone tissue grew into the scaffold in experimental group than the control group evaluated by Micro-CT (three months: 29.66% VS 20.35%, P<0.05; six months: 30.47% VS 25.10%, P<0.05) and histological analysis (24.71% VS 16.45%, P<0.05 â€‹at three months; 31.01% VS 20.60%, P<0.05 â€‹at six months). Implanted vascular bundles had the potential to branch out many branches in the osteonecrosis repair area to facilitate blood supply reconstruction and bone repair. CONCLUSIONS: This study proposed a novel device with clinical application prospects in the treatment of ONFH. It has the potential to provide new possibilities for rebuilding the blood supply of femoral head and repairing osteonecrosis. TRANSLATIONAL POTENTIAL STATEMENT: The novel device proposed in this study has the potential to be applied to the treatment of early femoral head necrosis.

12.
Elife ; 102021 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-34254584

RESUMO

Breast cancer type two susceptibility protein (BRCA2) is an essential protein in genome maintenance, homologous recombination (HR), and replication fork protection. Its function includes multiple interaction partners and requires timely localization to relevant sites in the nucleus. We investigated the importance of the highly conserved DNA-binding domain (DBD) and C-terminal domain (CTD) of BRCA2. We generated BRCA2 variants missing one or both domains in mouse embryonic stem (ES) cells and defined their contribution in HR function and dynamic localization in the nucleus, by single-particle tracking of BRCA2 mobility. Changes in molecular architecture of BRCA2 induced by binding partners of purified BRCA2 were determined by scanning force microscopy. BRCA2 mobility and DNA-damage-induced increase in the immobile fraction were largely unaffected by C-terminal deletions. The purified proteins missing CTD and/or DBD were defective in architectural changes correlating with reduced HR function in cells. These results emphasize BRCA2 activity at sites of damage beyond promoting RAD51 delivery.


Assuntos
Proteína BRCA2/química , Proteína BRCA2/genética , Reparo do DNA , Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/genética , Conformação de Ácido Nucleico , Animais , Proteína BRCA2/metabolismo , DNA/química , DNA/metabolismo , Replicação do DNA , Proteínas de Ligação a DNA/metabolismo , Recombinação Homóloga , Humanos , Camundongos , Células-Tronco Embrionárias Murinas , Rad51 Recombinase/genética , Rad51 Recombinase/metabolismo , Imagem Individual de Molécula
13.
Cancers (Basel) ; 13(6)2021 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-33808973

RESUMO

Cancer treatments based on mild hyperthermia (39-43 °C, HT) are applied to a widening range of cancer types, but several factors limit their efficacy and slow down more widespread adoption. These factors include difficulties in adequate heat delivery, a short therapeutic window and the acquisition of thermotolerance by cancer cells. Here, we explore the biological effects of HT, the cellular responses to these effects and their clinically-relevant consequences. We then identify the heat stress response-the cellular defense mechanism that detects and counteracts the effects of heat-as one of the major forces limiting the efficacy of HT-based therapies and propose targeting this mechanism as a potentially universal strategy for improving their efficacy.

14.
Minerva Anestesiol ; 87(6): 684-694, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33594873

RESUMO

INTRODUCTION: The aim of this study was to summarize the incidence and risk factors of postoperative delirium (POD) after liver transplantation (LT) and associations of POD after LT with outcomes. EVIDENCE ACQUISITION: A literature search of Pubmed, EMBASE, and the Cochrane Databases was performed to identify studies reporting POD after LT. The Newcastle-Ottawa Scale was used to rate study quality. Effect estimates were extracted and combined using random-effect model. Pooled mean differences and odds ratios for individual risk factors were calculated using inverse-variance method and Mantel-Haenszel method, as appropriate. EVIDENCE SYNTHESIS: Eight articles with 1434 patients were included in the meta-analysis. Overall, the pooled estimated incidence rates of POD after LT were 30% (95% confidence interval: 20-39%). Fourteen statistically significant risk factors were identified in the pooled analysis: alcohol excess, preoperative renal replacement therapy (RRT), preoperative hospital length of stay (LOS), depression, hepatic encephalopathy, alcohol etiology of liver failure, Child-Turcotte-Pugh Score, APACHE II Score, MELD Score, preoperative INR, preoperative bilirubin, intraoperative use of fentanyl, intraoperative RBC transfusion, postoperative ammonia. Patients with POD had a significantly increased mechanical ventilation, postoperative RRT, LOS and mortality rate compared with those without POD. CONCLUSIONS: POD after LT was common and multifactorial in etiology. There are significant associations of POD after LT with some clinical outcomes. Effective interventions during perioperative period may be promising to reduce the risk of POD after LT.


Assuntos
Delírio , Transplante de Fígado , Delírio/epidemiologia , Delírio/etiologia , Humanos , Incidência , Complicações Pós-Operatórias/epidemiologia , Fatores de Risco
15.
Tissue Cell ; 68: 101438, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33220596

RESUMO

Cancer pain, especially bone cancer pain, is a pain state often caused by inflammation or dysfunctional nerves. Moreover, in the management of cancer pain, opioid especially morphine is widely used, however, it also brings severe side effects such as morphine tolerance to the patient (Deandrea et al., 2008). A growing body of literatures demonstrated that neuroinflammation is mediated by microglia. As the macrophages like immune cells, microglia play an important role in the pathogenesis of cancer pain and morphine tolerance. Microglia acquire different activation states to regulate the function of these cells. As to M1 phenotype, microglia release pro-inflammatory cytokines and neurotoxic molecules that promote inflammation and cytotoxic reactions. Conversely, when microglia represent M2 phenotypes secreting anti-inflammatory cytokines and nutrient factors that promote the function of repair, regeneration and restore homeostasis. A better understanding of microglia activation in cancer pain and morphine tolerance is crucial for the development of hypothesized neuroprotective drugs. Targeting microglia different polarization states by the inhibition of their deleterious pro-inflammatory neurotoxicity and/or enhancing their beneficial anti-inflammatory protective function seems to be an effective treatment for cancer pain and morphine tolerance.


Assuntos
Dor do Câncer/patologia , Tolerância a Medicamentos , Microglia/patologia , Morfina/farmacologia , Animais , Humanos , Inflamação/patologia , Modelos Biológicos
16.
J Pharmacol Sci ; 144(4): 237-244, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33070843

RESUMO

Hypoxic pulmonary hypertension (HPH) is a progressive and irreversible disease that reduces survival. Echinacoside is a phenylethanoid glycoside from Tibetan herbs known for its vasorelaxant effect and for inhibiting the proliferation of rat pulmonary arterial smooth muscle cells. This study aimed to investigate the effect of echinacoside on HPH. Sprague Dawley rats were housed in a hypobaric hypoxia chamber (4500 m) for 28 days to obtain the HPH model. Echinacoside (3.75, 7.5, 15, 30 and 40 mg/kg) was administered by intraperitoneal injection from the 1st to the 28th day. The mean pulmonary artery pressure (mPAP), right ventricular hypertrophy index, hemoglobin, hematocrit, red blood cell concentration and morphological change of pulmonary arteries were evaluated. Vascular perfusion assay was used to assess the pulmonary artery function. Echinacoside reduced mPAP, hemoglobin, hematocrit, right ventricular hypertrophy index and mean wall thickness% of pulmonary arteries in HPH rats. It significantly increased maximum vasoconstriction percentage of pulmonary arteries induced by noradrenaline in a dose-dependent manner. In addition, it improved the responsiveness of pulmonary arteries to acetylcholine and sodium nitroprusside. Therefore, Echinacoside might be an effective treatment against HPH, since it regulated pulmonary artery endothelium and smooth muscle layer function and improved the remodeling of pulmonary artery.


Assuntos
Glicosídeos/administração & dosagem , Glicosídeos/farmacologia , Hipertensão Pulmonar/tratamento farmacológico , Hipertensão Pulmonar/etiologia , Hipóxia/complicações , Fitoterapia , Artéria Pulmonar/efeitos dos fármacos , Artéria Pulmonar/fisiopatologia , Remodelação Vascular/efeitos dos fármacos , Vasoconstrição/efeitos dos fármacos , Animais , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Glicosídeos/uso terapêutico , Hipertensão Pulmonar/fisiopatologia , Hipertensão Pulmonar/prevenção & controle , Técnicas In Vitro , Injeções Intraperitoneais , Masculino , Ratos Sprague-Dawley , Vasodilatadores
17.
Org Lett ; 22(19): 7640-7644, 2020 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-32929972

RESUMO

A silver-catalyzed cascade cyclization reaction of isocyanides with sulfoxonium ylides has been developed for the first time. This reaction provides a new and efficient method for the construction of highly functionalized 3-aminofurans and 4-aminoquinolines from readily available starting materials in a single step.

18.
BMC Nephrol ; 21(1): 223, 2020 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-32527305

RESUMO

BACKGROUND: Acute kidney injury (AKI) is a common postoperative complication of orthotopic liver transplantation (OLT). So far, little attention has been paid on the association between overweight and AKI after OLT, and animal models or clinical studies have drawn conflicting conclusions. The objective of our study was to determine whether overweight (BMI [Body Mass Index] ≥ 25 kg/m2) is associated with an increased risk of AKI after OLT. METHODS: This retrospective cohort study included 244 patients receiving OLT in the Affiliated Hospital of Qingdao University between January 1, 2017, and August 29, 2019. Preoperative, intraoperative, and postoperative data were collected retrospectively. The primary outcome was the development of AKI as defined by Kidney Disease, Improving Global Outcome (KIDGO) staging system. Logistic regression analysis was used to determine the relationship between overweight and the occurrence of postoperative AKI. Data analysis was conducted from September to October 2019, revision in April 2020. RESULTS: Among 244 patients receiving OLT (mean [standard deviation] age, 54.1 [9.6] years; 84.0% male) identified, 163 patients (66.8%) developed postoperative AKI. Overweight (BMI ≥ 25 kg/m2) was associated with a higher rate of postoperative severe AKI (stage 2/3) compared with normal weight (18.5 ≤ BMI < 25 kg/m2) (41 [47.7%] vs 39 [28.7%]; adjusted odds ratio [OR], 2.539; 95% confidence interval [CI], 1.389-4.642; P = 0.002). Furthermore, patients with obese were at even higher risk of postoperative severe AKI after controlling for confounding factors (adjusted OR: 3.705; 95% CI: 1.108-12.388; P = 0.033). CONCLUSIONS: Overweight is independently associated with an increased risk of postoperative severe AKI among patients receiving OLT. The association of BMI with severe AKI after OLT is J-shaped.


Assuntos
Injúria Renal Aguda/etiologia , Doença Hepática Terminal/complicações , Transplante de Fígado , Sobrepeso/complicações , Complicações Pós-Operatórias/etiologia , Adulto , Doença Hepática Terminal/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
20.
Cell Prolif ; 53(1): e12698, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31588640

RESUMO

Advances in transcriptome sequencing have revealed that the genome fraction largely encodes for thousands of non-coding RNAs. Long non-coding RNAs (lncRNAs), which are a class of non-protein-coding RNAs longer than approximately 200 nucleotides in length, are emerging as key epigenetic regulators of gene expression recently. Intensive studies have characterized their crucial roles in cutaneous biology and diseases. In this review, we address the promotive or suppressive effects of lncRNAs on cutaneous physiological processes. Then, we focus on the pathogenic role of dysfunctional lncRNAs in a variety of proliferative skin diseases. These evidences suggest that lncRNAs have indispensable roles in the processes of skin biology. Additionally, lncRNAs might be promising biomarkers and therapeutic targets for cutaneous disorders.


Assuntos
Proliferação de Células , RNA Longo não Codificante/metabolismo , Dermatopatias/metabolismo , Pele/metabolismo , Animais , Humanos , Pele/patologia , Dermatopatias/patologia
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