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1.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 45(4): 581-590, 2023 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-37654138

RESUMO

Objective To investigate the effects of Weidiao-3(WD-3)Mixture on the clinical efficacy of immunotherapy for advanced gastric cancer and the intestinal flora.Methods Fifty-one patients with advanced gastric cancer treated in Wuxi Traditional Chinese Medicine Hospital from January 2020 to December 2021 were randomized into a WD-3 group(immunotherapy + WD-3 Mixture,one dose per day)(n=25)and a gastric cancer(GC) group(only immunotherapy)(n=26)according to the admission time.Ten healthy volunteers were included as the healthy control group.The Karnofsky score and the Quality of Life Questionnare-Core score were evaluated before and after treatment,and the clinical efficacy was compared after treatment.After treatment,the stool samples were collected for 16SrRNA gene high-throughput sequencing and targeted metabolomics.The α and ß diversity and structure of the intestinal flora and the content of short-chain fatty acids were compared between groups.Results The quality of life in both groups improved after treatment and was better in the WD-3 group than in the GC group(P=0.035).The dry mouth(P=0.038)and altered taste(P=0.008)were mitigated in the WD-3 group after treatment,and the reflux(P=0.001)and dry mouth(P=0.022)were mitigated in the GC group after treatment.After treatment,the WD-3 group outperformed the GC group in terms of dysphagia(P=0.047)and dry mouth(P=0.045).The WD-3 group was superior to the GC group in terms of objective remission rate and disease control rate,with prolonged median progression-free survival and median overall survival(P=0.039,P=0.043).The α and ß diversity indexes of the intestinal flora showed no significant differences between WD-3 and GC groups(all P>0.05).At the phylum level,WD-3 and GC groups had lower relative abundance of Firmicutes(P=0.038,P=0.042)and higher relative abundance of Proteobacteria(P=0.016,P=0.015)than the healthy control group.The relative abundance of Actinomycetes in the GC group was lower than that in the healthy control group(P=0.035)and the WD-3 group(P=0.046).At the genus level,the GC group had lower relative abundance of Bifidobacteria and Coprococcus than the healthy control group and the WD-3 group(all P<0.001).LEfSe revealed the differences in the relative abundance of 6 intestinal bacterial taxa between the WD-3 group and the GC group.At the genus level,Saccharopolyspora had higher relative abundance in the WD-3 group than in the healthy control group and only existed in the WD-3 group.The content of isobutyric acid and isovaleric acid in the WD-3 group was higher than that in the healthy control group(P=0.037,P=0.004).Conclusion WD-3 Mixture may increase the relative abundance of Bifidobacteria and Coprococcus and the content of isobutyric acid and isovaleric acid to alter the intestinal microecology,thereby improving the efficacy of immunotherapy for gastric cancer.


Assuntos
Microbioma Gastrointestinal , Neoplasias Gástricas , Humanos , Isobutiratos , Qualidade de Vida , Neoplasias Gástricas/terapia , Imunoterapia , Resultado do Tratamento
2.
Pest Manag Sci ; 79(11): 4626-4634, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37442803

RESUMO

BACKGROUND: Bacterial wilt induced by Ralstonia solanacearum is regarded as one of the most devastating diseases. However, excessive and repeated use of the same bactericides has resulted in development of bacterial resistance. Targeting bacterial virulence factors, such as type III secretion system (T3SS), without inhibiting bacterial growth is a possible assay to discover new antimicrobial agents. RESULTS: In this work, identifying new T3SS inhibitors, a series of mandelic acid derivatives with 2-mercapto-1,3,4-thiazole moiety was synthesized. One of them, F-24, inhibited the transcription of hrpY gene significantly. The presence of this compound obviously attenuated hypersensitive response (HR) without inhibiting bacterial growth of R. solanacearum. The transcription levels of those typical T3SS genes were reduced to various degrees. The test of the ability of F-24 in protecting plants demonstrated that F-24 protected tomato plants against bacterial wilt without restricting the multiplication of R. solanacearum. The mechanism of this T3SS inhibition is through the PhcR-PhcA-PrhG-HrpB pathway. CONCULSION: The screened F-24 could inhibit R. solanacearum T3SS and showed better inhibitory activity than previously reported inhibitors without affecting the growth of the strain, and F-24 is a compound with good potential in the control of R. solanacearum. © 2023 Society of Chemical Industry.

3.
Diagnostics (Basel) ; 12(7)2022 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-35885650

RESUMO

Melanoma, a very severe form of skin cancer, spreads quickly and has a high mortality rate if not treated early. Recently, machine learning, deep learning, and other related technologies have been successfully applied to computer-aided diagnostic tasks of skin lesions. However, some issues in terms of image feature extraction and imbalanced data need to be addressed. Based on a method for manually annotating image features by dermatologists, we developed a melanoma detection model with four improvement strategies, including applying the transfer learning technique to automatically extract image features, adding gender and age metadata, using an oversampling technique for imbalanced data, and comparing machine learning algorithms. According to the experimental results, the improved strategies proposed in this study have statistically significant performance improvement effects. In particular, our proposed ensemble model can outperform previous related models.

4.
Bioengineered ; 13(3): 4857-4868, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35156516

RESUMO

MiR-664b-3p has been reported to play a crucial role in cancer progression. This research explores the biological effect and molecular mechanisms of miR-664b-3p in cell proliferation, apoptosis, migration, and invasion of colon cancer. The expression level of miR-664b-3p and Budding uninhibited by benzimidazole 3 (Bub3) in colon cancer cell lines and tissues were detected and analyzed using quantitative real-time PCR and bioinformatics method. The Western blot measured the expression level of proliferation-related, migration-related, and apoptosis-related proteins. CCK-8 assessed cell viability, and the cell proliferation, migration, and invasion were detected by the Edu assay, wound-healing assay, and transwell assay, respectively. Annexin/propidium iodide (PI) assays detected apoptosis of cells. The target of miR-664b-3p was predicted by bioinformatics methods and then validated by gene engineering technology. MiR-664b-3p was downregulated in colon cancer tissues and cells. The cell proliferation, migration, and invasion of cells were inhibited after transfecting by miR-664b-3p mimics, whereas apoptosis was promoted. Over-expression of miR-664b-3p could reduce the expression of proliferation-promoted proliferating cell nuclear antigen (PCNA), proliferation marker protein Ki-67 (Ki-67), migration-promoted Cyclooxygenase-2 (COX-2), Matrix Metallopeptidase 2 (MMP-2), and Matrix Metallopeptidase 9 (MMP-9), and apoptosis-inhibited protein (Bcl-2) while increasing the expression of apoptosis-promoted BCL2-Associated X Protein (Bax), caspase-3, and caspase-9 proteins. The study indicated that miR-664b-3p plays a significant role in colon cancer and could regulate the progression of colon cancer tumor growth by suppressing the expression of BUB3 protein. These findings provide a novel strategy to screen and treat colon cancer.


Assuntos
Carcinoma , Proteínas de Ciclo Celular , Neoplasias do Colo , MicroRNAs , Proteínas de Ligação a Poli-ADP-Ribose , Apoptose/genética , Carcinoma/genética , Proteínas de Ciclo Celular/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Neoplasias do Colo/genética , Neoplasias do Colo/patologia , Regulação Neoplásica da Expressão Gênica , Humanos , Antígeno Ki-67/genética , Metaloproteases/genética , MicroRNAs/genética , Proteínas de Ligação a Poli-ADP-Ribose/genética
5.
Int J Ophthalmol ; 15(1): 1-8, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35047349

RESUMO

AIM: To explore the effect of miR-184 and miR-205 on the proliferation and metastasis of conjunctival mucosa associated lymphoid tissue (MALT) lymphoma. METHODS: Tissue of tumor and adjacent normal control from 5 patients with conjunctival MALT was included. RPMI8226 cell line was selected to verify the effect of miRNAs in B cells. The function of microRNA on the RPMI8226 cell apoptosis, migration and invasion was evaluated by apoptosis assay and Transwell assay. The mRNA and protein expression were examined by quantitative RT-PCR and Western blotting. The effect of microRNA on regulation of downstream gene expression was evaluated by luciferase report assay. RESULTS: A decreased level of miR-184 and miR-205 was observed in MALT lymphoma tissue. Exogenous miR-184 and miR-205 analogues promoted apoptosis, and inhibited the survival, migration, and invasion of RPMI8226 cells. miR-184 and miR-205 inhibitor reversed the process. The RNA and protein level of RasL10B and TNFAIP8 were downregulated in MALT lymphoma tissue. The exogenous of miR-184 and miR-205 promoted the expression of RasL10B and TNFAIP8. Meanwhile, inhibition of miR-184 and miR-205 repressed the expression of target gene, RasL10B and TNFAIP8. CONCLUSION: miR-184 and miR-205 suppresses the tumorigenesis of conjunctival MALT lymphoma through regulating RasL10B and TNFAIP8.

6.
Plant Signal Behav ; 16(6): 1913307, 2021 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-33853508

RESUMO

Light is an important environmental factor for plant growth and development. Phytochrome B (phyB), a classical red/far-red light receptor, plays vital role in controlling plant photomorphogenesis and light-induced stomatal opening. Phytohormone abscisic acid (ABA) accumulates rapidly and triggers a series of physiological and molecular events during the responses to multiple abiotic stresses. Recent studies showed that phyB mutant synthesizes more ABA and exhibits improved tolerance to salt and cold stress, suggesting that a crosstalk exists between light and ABA signaling pathway. However, whether ABA signaling components mediate responses to light remains unclear. Here, we showed that SnRK2.6 (Sucrose Nonfermenting 1-Related Protein Kinase 2.6), a key regulator in ABA signaling, interacts with phyB and participates in light-induced stomatal opening. First, we checked the interaction between phyB and SnRK2s, and found that SnRK2.2/2.3/2.6 kinases physically interacted with phyB in yeast and in vitro. We also performed co-IP assay to support that SnRK2.6 interacts with phyB in plant. To investigate the role of SnRK2.6 in red light-induced stomatal opening, we obtained the snrk2.6 mutant and overexpression lines, and found that snrk2.6 mutant exhibited a significantly larger stomatal aperture under red light treatment, while the two independent overexpression lines showed significantly smaller stomatal aperture, indicative of a negative role for SnRK2.6 in red light-induced stomatal opening. The interaction of SnRK2.6 with red light receptor and the negative role of SnRK2.6 in red light-induced stomatal opening provide new evidence for the crosstalk between ABA and red light in guard cell signaling.


Assuntos
Fitocromo B/genética , Fitocromo B/metabolismo , Estômatos de Plantas/genética , Estômatos de Plantas/fisiologia , Proteínas Quinases/genética , Proteínas Quinases/metabolismo , Saccharomyces/crescimento & desenvolvimento , Saccharomyces/genética , Adaptação Ocular/genética , Adaptação Ocular/fisiologia , Regulação da Expressão Gênica de Plantas , Genes de Plantas
7.
Chin Med J (Engl) ; 133(24): 2905-2909, 2020 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-33177393

RESUMO

BACKGROUND: Benvitimod cream, a novel synthetic small molecule, was effective in treating mild-to-moderate plaque psoriasis. We conducted a phase III clinical trial to assess the efficacy and safety of benvitimod cream in patients with mild-to-moderate plaque psoriasis. METHODS: We randomly assigned 686 patients (2:1:1) to receive 1% benvitimod cream, 0.005% calcipotriol ointment or placebo twice a day for 12 weeks. The primary efficacy end points were the percentage of patients with a 75% or greater reduction from baseline in the psoriasis area and severity index (PASI 75) score and with a score of 0 or 1 in static physician's global assessment (sPGA) at week 12. RESULTS: The results showed that 50.4% of patients in the benvitimod group achieved PASI 75, which was significantly higher than that in the calcipotriol (38.5%, P < 0.05) and placebo (13.9%, P < 0.05) groups. The proportion of patients achieving an sPGA score 0 or 1 was 66.3% in the benvitimod group and 63.9% in the calcipotriol group, which were both significantly higher than that in the placebo group (34%, P < 0.05). In the long-term follow-up study, 50.8% of patients experienced recurrence. After retreatment with 1% benvitimod, 73.3% of patients achieved an sPGA score of 0 or 1 again at week 52. Adverse events included application site irritation, follicular papules, and contact dermatitis. No systemic adverse reactions were reported. CONCLUSION: During this 12-week study, benvitimod cream was demonstrated with high effectiveness and safety in patients with mild-to-moderate plaque psoriasis. TRIAL REGISTRATION: Chinese Clinical Trial Registry (ChiCTR), ChiCTR-TRC-13003259; http://www.chictr.org.cn/showprojen.aspx?proj=6300.


Assuntos
Psoríase , Método Duplo-Cego , Seguimentos , Humanos , Pomadas , Psoríase/tratamento farmacológico , Resorcinóis , Índice de Gravidade de Doença , Estilbenos , Resultado do Tratamento
8.
Mycoses ; 63(11): 1235-1243, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33090565

RESUMO

BACKGROUND: In China, the prevalence of superficial fungal infections of the foot is high and recurrence is common. However, a prospective, large-scale and multicentre study on the aetiology of superficial fungal infections of the foot is still lacking. OBJECTIVES: To study the epidemiology of aetiological agents of superficial fungal infections of the foot in urban outpatients in mainland China, as well as to understand the aetiology features of the pathogenic agent. METHODS: The study was designed as a multicentre, prospective epidemiological survey. A total of 1704 subjects were enrolled from seven geographical areas in mainland China. For each subject, one mycological sample and one bacterial sample were collected. KOH wet mount examination and culture were performed at local laboratories. The bacterial results were only reported in those with positive mycology. Further morphological identification and, if necessary, molecular biological identification were conducted in a central laboratory. RESULTS: Of 1704 enrolled subjects, 1327 (77.9%) subjects had positive fungal culture results. The incidence of dermatophytes, yeasts and moulds was 90.1%, 8.1% and 1.1%, respectively. The most frequently isolated aetiological agent (fungus) was Trichophyton rubrum. Moccasin form was the most commonly reported clinical diagnosis of superficial fungal infections. The most frequently isolated bacterial genus in patients was Staphylococcus. CONCLUSION: This study prospectively investigated the clinical and mycological features of human dermatophytosis in mainland China. T rubrum was the most frequently isolated fungus, and moccasin form was the most commonly reported clinical diagnosis of superficial fungal infections.


Assuntos
Dermatomicoses , Pé/microbiologia , Adulto , Arthrodermataceae/isolamento & purificação , Arthrodermataceae/patogenicidade , China/epidemiologia , Dermatomicoses/epidemiologia , Dermatomicoses/etiologia , Dermatomicoses/patologia , Feminino , Pé/patologia , Fungos/isolamento & purificação , Fungos/patogenicidade , Humanos , Incidência , Masculino , Micoses/epidemiologia , Micoses/etiologia , Micoses/patologia , Pacientes Ambulatoriais , Prevalência , Estudos Prospectivos , Leveduras/isolamento & purificação , Leveduras/patogenicidade
9.
Artigo em Inglês | MEDLINE | ID: mdl-34192088

RESUMO

The 2019 novel coronavirus infection has brought a great challenge in prevention and control of the national epidemic of coronavirus disease 2019 (COVID-19) in China. During the fight against the epidemic of COVID-19, properly carrying out pre-examination and triage for patients with skin lesions and fever has been a practical problem encountered in hospitals for skin diseases as well as clinics of dermatology in general hospitals. Considering that certain skin diseases may have symptom of fever, and some of the carriers of 2019 novel coronavirus and patients with COVID-19 at their early stage may do not present any symptoms of COVID-19, to properly deal with the visitors to clinics of dermatology, the Chinese Society of Dermatology organized experts to formulate the principles and procedures for pre-examination and triage of visitors to clinics of dermatology during the epidemic of COVID-19.

10.
Shock ; 53(3): 363-372, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31135707

RESUMO

BACKGROUND: Impaired autophagic flux contributes to cardiomyocyte death in ischemia/reperfusion (I/R) injury. Restoring the impaired autophagic flux by using agents may be a promising strategy that alleviates myocardial I/R injury. The present study aimed to evaluate the effect of exogenous calreticulin (CRT) postconditioning on impaired autophagic flux induced by hypoxia/reoxygenation (H/R) injury in H9c2 cells. METHODS: Rat myocardial I/R injury model was prepared. CRT postconditionging was fulfilled by an intraperitoneal injection of CRT (0.5 mg/kg body weight) 5 min before reperfusion. Hemodynamics, serum lactate dehydrogenase (LDH) activity and Cardiac troponin T (TnT) content, and infarct size were measured. The H/R injury model of H9c2 cells was prepared. CRT postconditioning was performed by adding 25 pg/mL CRT to the medium at the onset of reoxygenation. Cell death rate, lactate dehydrogenase (LDH) leakage, intracellular reactive oxygen species (ROS), and malondialdehyde (MDA) were assessed. Autophagic flux was monitored by mRFP-GFP-LC3 adenovirus infection. The number of autophagosomes and autolysosomes in cells were determined by counting the fluorescence dots. Western blot assay was used to determine the expression of autophagy-related proteins. RESULTS: CRT postconditionging improved cardiac function, reduced serum LDH activity and TnT content, and limited myocardial infarct size after myocardial I/R injury in rat. H/R induced H9c2 cells injury and autophagosomes accumulation in cells. CRT postconditioning attenuated H/R-induced cell death, LDH leakage, and the increase of intracellular ROS and MDA. Meanwhile, CRT postconditioning suppressed H/R-induced excessive formation of autophagosomes, as shown by a decrease of autophagosomes and the ratio of LC3-II/LC3-I, LC3-II, and Beclin1. It also improved H/R-induced impaired autophagosomes clearance, as shown by an increase of autolysosomes and the level of LAMP-2, and a decrease of the level of p62. CONCLUSION: These findings suggested that CRT postconditioning reduced myocardial I/R injury. CRT postconditioning also inhibited the excessive formation of autophagosomes, promoted the clearance of autophagosomes, and resorted the autophagic flux, consequently reduced the H/R injury in H9c2 cells.


Assuntos
Calreticulina/uso terapêutico , Pós-Condicionamento Isquêmico/métodos , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Animais , Autofagia , Técnicas de Cultura de Células , Modelos Animais de Doenças , Traumatismo por Reperfusão Miocárdica/patologia , Miócitos Cardíacos/patologia , Ratos , Ratos Sprague-Dawley
11.
Arch Dermatol Res ; 312(6): 437-445, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31873772

RESUMO

Etanercept biosimilar recombinant human tumour necrosis factor-α receptor II: IgG Fc fusion protein (rhTNFR-Fc, trade name Yisaipu) has shown good efficacy in the treatment of moderate-to-severe plaque psoriasis. To compare the efficacy and safety of rhTNFR-Fc plus methotrexate (MTX) and rhTNFR-Fc plus placebo in Chinese patients with moderate-to-severe plaque psoriasis. In this multicentre, randomized, placebo-controlled trial, patients with moderate-to-severe plaque psoriasis were enrolled and randomly assigned in a 1:1 ratio to receive rhTNFR-Fc plus MTX or rhTNFR-Fc plus placebo. The primary endpoint was the proportion of patients achieving Psoriasis Area and Severity Index improvement of at least 75% (PASI 75) from baseline at week 24. Adverse events (AEs) were recorded to evaluate safety. Efficacy analysis was performed using the intent-to-treat principle. A total of 466 patients were enrolled and randomly received rhTNFR-Fc plus MTX (combination group, n = 233) or rhTNFR-Fc plus placebo (monotherapy group, n = 233). PASI 75 at week 24 was significantly higher in the combination group than in the monotherapy group (81.86% vs. 65.50%, p < 0.001). Similar results were observed in other PASI improvement scores at week 12 [PASI 75, 62.39% vs. 44.54% (p < 0.001); PASI 50, 87.17% vs. 75.55% (p = 0.001); and PASI 90, 34.07% vs. 18.78% (p < 0.001)] and week 24 [PASI 50, 92.48% vs. 85.59% (p = 0.019); and PASI 90, 64.16% vs. 42.36% (p < 0.001)]. Significantly more patients had a static Physicians' Global Assessment of clear or almost clear in the combination group than in the monotherapy group at week 12 (26.46% vs. 12.50%, p < 0.001) and week 24 (62.38% vs. 40.83%, p < 0.001). The most common AEs in the two groups were upper respiratory tract infection and abnormal liver function. The combination therapy of rhTNFR-Fc plus MTX was an effective therapy for moderate-to-severe plaque psoriasis with an acceptable safety and tolerability profile, indicating that it was feasible and well tolerated for patients.


Assuntos
Etanercepte/uso terapêutico , Fragmentos Fc das Imunoglobulinas/genética , Imunoglobulina G/genética , Metotrexato/uso terapêutico , Psoríase/tratamento farmacológico , Receptores Tipo II do Fator de Necrose Tumoral/genética , Proteínas Recombinantes de Fusão/genética , Adulto , Medicamentos Biossimilares , China , Método Duplo-Cego , Quimioterapia Combinada , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Placebos , Índice de Gravidade de Doença , Resultado do Tratamento
12.
Clin Sci (Lond) ; 133(9): 1067-1084, 2019 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-31015359

RESUMO

Accumulation of reactive oxygen species is a common phenomenon in cardiac stress conditions, for instance, coronary artery disease, aging-related cardiovascular abnormalities, and exposure to cardiac stressors such as hydrogen peroxide (H2O2). Mitochondrial protein 18 (Mtp18) is a novel mitochondrial inner membrane protein, shown to involve in the regulation of mitochondrial dynamics. Although Mtp18 is abundant in cardiac muscles, its role in cardiac apoptosis remains elusive. The present study aimed to detect the role of Mtp18 in H2O2-induced mitochondrial fission and apoptosis in cardiomyocytes. We studied the effect of Mtp18 in cardiomyocytes by modulating its expression with lentiviral construct of Mtp18-shRNA and Mtp18 c-DNA, respectively. We then analyzed mitochondrial morphological dynamics with MitoTracker Red staining; apoptosis with terminal deoxynucleotidyl transferase-mediated dUTP nick-end-labeling (TUNEL) and cell death detection assays; and protein expression with immunoblotting. Here, we observed that Mtp18 could regulate oxidative stress- mediated mitochondrial fission and apoptosis in cardiac myocytes. Mechanistically, we found that Mtp8 induced mitochondrial fission and apoptosis by enhancing dynamin-related protein 1 (Drp1) accumulation. Conversely, knockdown of Mtp18 interfered with Drp1-associated mitochondrial fission and subsequent activation of apoptosis in both HL-1 cells and primary cardiomyocytes. However, overexpression of Mtp18 alone was not sufficient to execute apoptosis when Drp1 was minimally expressed, suggesting that Mtp18 and Drp1 are interdependent in apoptotic cascade. Together, these data highlight the role of Mtp18 in cardiac apoptosis and provide a novel therapeutic insight to minimize cardiomyocyte loss via targetting mitochondrial dynamics.


Assuntos
Apoptose/fisiologia , Mitocôndrias/metabolismo , Proteínas Mitocondriais/metabolismo , Miócitos Cardíacos/metabolismo , Estresse Oxidativo/fisiologia , Animais , Peróxido de Hidrogênio/metabolismo , Dinâmica Mitocondrial/fisiologia , Miocárdio/metabolismo , Miócitos Cardíacos/citologia , Ratos , Espécies Reativas de Oxigênio/metabolismo
13.
Org Lett ; 21(7): 2369-2373, 2019 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-30883133

RESUMO

An iterative protocol was developed for highly diastereo- and enantioselective construction of high-order 1,3-polyols via iridium-catalyzed asymmetric hydrogenation of ß-alkyl-ß-keto esters. The protocol involves four operations-asymmetric hydrogenation, hydroxy protection, ester hydrolysis, and C-acylation-and the catalyst loading can be as low as 0.005 mol %. The configurations of all stereogenic centers of 1,3-polyols are controlled by the catalyst. By the use of this protocol, a formal total synthesis of the polyketide cyanolide A was achieved with high diastereoselectivity and enantioselectivity.

14.
Acta Physiol (Oxf) ; 225(4): e13228, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30507035

RESUMO

The rhythmic contraction of cardiomyocytes consumes a lot of energy. 90% of ATP in cardiomyocytes is produced by mitochondria. Maintenance of a healthy population of mitochondria by mitophagy is critical for cardiomyocyte survival and normal function. Mitophagy refers to selective removal of damaged mitochondria by autophagy mechanism. The process of mitophagy must be restricted to dysfunctional mitochondria and maintained at a balanced level. Disruption in the balance inevitably leads to cardiomyocyte injury and dysfunction. Accumulating evidence suggests that mitophagy plays a pivotal role in ischaemia/reperfusion-induced cardiomyocyte injury. In this review, we focus on the current understanding of mitophgy in cardiomyocyte function, the implications for cardiomyocyte injury in response to ischaemia/reperfusion as well as their underlying potential mechanisms.


Assuntos
Mitofagia , Traumatismo por Reperfusão Miocárdica/etiologia , Miócitos Cardíacos/fisiologia , Animais , Humanos
15.
Front Chem ; 7: 850, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31921773

RESUMO

Aminic radical-trapping antioxidants (RTAs), as one of the most important antioxidants, have not received sufficient attention yet. But, an increasing number of aminic RTAs have been identified as ferroptosis inhibitors in recent years, which can potentially mediate many pathological states including inflammation, cancer, neurodegenerative disease, as well as ocular and kidney degeneration. This highlights the importance of aminic RTAs in the field of medicine. Herein, we systematically explored the radical scavenging mechanism of aminic RTAs with a quantum chemical method, particularly emphasizing the role of stereoelectronic factors and resonance factors on the transfer of H-atom and the stability to one-electron oxidation. These theoretical results elucidate the diversity of free radical scavenging mechanisms for aminic RTAs, and has significant implications for the rational design of new aminic RTAs.

16.
Org Biomol Chem ; 16(21): 3952-3960, 2018 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-29749412

RESUMO

Ferroptosis is a non-apoptotic, iron dependent form of regulated cell death that is characterized by the accumulation of lipid hydroperoxides. It has drawn considerable attention owing to its putative involvement in diverse neurodegenerative diseases. Ferrostatins are the first identified inhibitors of ferroptosis and they inhibit ferroptosis by efficiently scavenging free radicals in lipid bilayers. However, their further medicinal application has been limited due to the deficient knowledge of the lipid peroxyl radical-trapping mechanism. In this study, experimental and theoretical methods were performed to illustrate the possible lipid hydroperoxide inhibition mechanism of ferrostatins. The results show that an ortho-amine (-NH) moiety from ferrostatins can simultaneously interact with lipid radicals, and then form a planar seven-membered ring in the transition state, and finally present greater reactivity. NBO analysis shows that the formed planar seven-membered ring forces ortho-amines into better alignment with the aromatic π-system. It significantly increases the magnitudes of amine conjugation and improves spin delocalization in the transition state. Additionally, a classical H-bond type interaction was discovered between a radical and an o-NH group as another transition state stabilizing effect. This type of radical-trapping mechanism is novel and has not been found in diphenylamine or traditional polyphenol antioxidants. It can be said that o-phenylenediamine is a privileged pharmacophore for the design and development of ferroptosis inhibitors.


Assuntos
Morte Celular/efeitos dos fármacos , Cicloexilaminas/farmacologia , Desenho de Fármacos , Fenilenodiaminas/farmacologia , Antioxidantes/farmacologia , Sequestradores de Radicais Livres , Humanos , Peróxidos Lipídicos/metabolismo , Peróxidos Lipídicos/farmacologia , Relação Estrutura-Atividade
17.
Cell Physiol Biochem ; 46(3): 890-906, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29669322

RESUMO

BACKGROUND/AIMS: Acute cerebral ischemia is a manifestation of cerebral vascular insufficiency and has a high mortality. However, the therapy for acute cerebral ischemia is still limited. This study aimed to investigate the effect of microRNA-381 (miR-381) on the repair of nerve injury in rats with acute cerebral ischemia after cerebral lymphatic blockage (CLB) by targeting leucine-rich repeat C4 protein (LRRC4) through the Stromal cell-derived factor-1/CXC chemokine receptor-4 signaling pathway. METHODS: Rat models of CLB and middle cerebral artery occlusion (MCAO) were established, and 56 Wistar rats were divided into sham, MCAO, CLB + MCAO, CLB + MCAO + miR-381 inhibitor, CLB + MCAO + miR-381 mimic, CLB + MCAO + AMD3100 and CLB + MCAO + miR-381 mimic + AMD3100 groups. Modified neurological severity score (mNSS was used to determine nerve injury, TTC staining to measure infarction volume, terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) staining and flow cytometry to evaluate cell apoptosis, immunofluorescence to measure BrdU-positive cell number, enzyme-linked immunosorbent assay (ELISA) to determine contents of tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß), interleukin-6 (IL-6), interleukin-10 (IL-10), nerve growth factor (NGF) and neurite outgrowth inhibitor -A (Nogo-A), Reverse transcription quantitative polymerase chain reaction (RT-qPCR) and Western blotting to evaluate expression of miR-381, LRRC4, SDF-1, CXCR4, pERK, Slit2 and vascular endothelial growth factor (VEGF). RESULTS: LRRC4 was a target gene of miR-381. Compared with the results in the CLB + MCAO group, mNSS, infarction volume, apoptosis rate and TNF-α, IL-1ß, IL-6 and Nogo-A contents as well as LRRC4 expression in the CLB + MCAO + miR-381 inhibitor and CLB + MCAO + AMD3100 groups were increased (those in the CLB + MCAO + AMD3100 group > those in the CLB + MCAO + miR-381 mimic + AMD3100 group), while BrdU-positive cell number, contents of NGF and IL-10, and expression of SDF-1, CXCR4, pERK, Slit2 and VEGF in brain tissues were decreased (those in the CLB + MCAO + AMD3100 group < those in the CLB + MCAO + miR-381 mimic + AMD3100 group). The results in the CLB + MCAO + mimic group were opposite of those in the CLB + MCAO + miR-381 inhibitor and CLB + MCAO + AMD3100 groups. CONCLUSION: Taken together, we concluded that up-regulation of miR-381 promoted nerve injury repair in acute cerebral ischemia rats after CLB by negatively regulating LRRC4 through activating the SDF-1/CXCR4 signaling pathway.


Assuntos
Isquemia Encefálica/patologia , Quimiocina CXCL12/metabolismo , MicroRNAs/metabolismo , Proteínas/metabolismo , Receptores CXCR4/metabolismo , Animais , Benzilaminas , Isquemia Encefálica/etiologia , Isquemia Encefálica/metabolismo , Quimiocina CXCL12/genética , Ciclamos , Modelos Animais de Doenças , Regulação para Baixo/efeitos dos fármacos , Compostos Heterocíclicos/farmacologia , Hipocampo/patologia , Infarto da Artéria Cerebral Média/complicações , Interleucina-1beta/análise , Proteínas de Repetições Ricas em Leucina , Masculino , MicroRNAs/antagonistas & inibidores , MicroRNAs/genética , Proteína Quinase 3 Ativada por Mitógeno/genética , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Proteínas/antagonistas & inibidores , Proteínas/genética , Ratos , Ratos Wistar , Receptores CXCR4/genética , Transdução de Sinais , Fator de Necrose Tumoral alfa/análise , Regulação para Cima/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo
18.
Int J Med Sci ; 14(13): 1368-1374, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29200950

RESUMO

Background:Pseudomonas aeruginosa can cause disease and also can be isolated from the skin of healthy people. Additionally, it exhibits certain antimicrobial effects against other microorganisms.Methods: We collected 60 strains of P. aeruginosa and screened their antimicrobial effects against Staphylococcus aureus (ATCC 25923) using the filter paper-disk method, the cross-streaking method and the co-culture method and then evaluated the antimicrobial activity of the chloroform-isolated S. aureus extracts against methicillin-resistant S. aureus (MRSA, Gram-positive cocci), vancomycin intermediate-resistant S. aureus (VISA, Gram-positive cocci), Corynebacterium spp. (CS, Gram-positive bacilli), Acinetobacter baumannii (AB, Gram-negative bacilli), Moraxella catarrhalis (MC, Gram-negative diplococcus), Candida albicans (CA, fungi), Candida tropicalis (CT, fungi), Candida glabrata (CG, fungi) and Candida parapsilosis (CP, fungi). Results: The PA06 and PA46 strains have strong antimicrobial effects. High-performance liquid chromatography (HPLC) analysis revealed that the major components of PA06 and PA46 that exhibit antimicrobial activity are functionally similar to phenazine-1-carboxylic acid (PCA) and pyocyanin. Preparative HPLC was performed to separate and isolate the 4 major potential antimicrobial components: PA06ER10, PA06ER16, PA06ER23 and PA06ER31. Further, the molecular masses of PA06ER10 (260.1), PA06ER16 (274.1), PA06ER23 (286.1) and PA06ER31 (318.2) were determined by electrospray ionization (ESI) mass spectrometry. Conclusion:P. aeruginosa can produce small molecules with potential antimicrobial activities against MRSA, VISA, CS, MC, CA, CT, CG and CP but not against AB.


Assuntos
Anti-Infecciosos/isolamento & purificação , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Pseudomonas aeruginosa/química , Infecções Estafilocócicas/tratamento farmacológico , Acinetobacter baumannii/efeitos dos fármacos , Acinetobacter baumannii/patogenicidade , Anti-Infecciosos/farmacologia , Candida albicans/efeitos dos fármacos , Candida albicans/patogenicidade , Extratos Celulares/química , Extratos Celulares/farmacologia , Corynebacterium/efeitos dos fármacos , Corynebacterium/patogenicidade , Humanos , Staphylococcus aureus Resistente à Meticilina/patogenicidade , Testes de Sensibilidade Microbiana , Infecções Estafilocócicas/microbiologia , Resistência a Vancomicina/efeitos dos fármacos
19.
ACS Appl Mater Interfaces ; 9(35): 29881-29888, 2017 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-28806505

RESUMO

Compared to natural enzymes, nanomaterial-based artificial enzymes have attracted immense attention because of their high stability and cost-effectiveness. In this study, cobalt nitride (Co4N) as a noble-metal-free artificial enzyme exhibiting highly intrinsic peroxidase-like activity and good stability was reported. Kinetic studies revealed that the resultant Co4N nanowires (NWs) exhibited a stronger affinity for 3,3',5,5'-tetramethylbenzidine (TMB) and H2O2 than HRP. Compared to Co3O4 NWs, Co4N NWs exhibited highly improved catalytic activities, with H2O2 exhibiting an apparent Km approximately 2 orders of magnitude less than that of Co3O4. In particular, the peroxidase-like activity of Co4N was maintained well over a wide range of temperatures and ionic strength. A Co4N-based method was further developed for the detection of glucose with good sensitivity and reliability. Because of advantages such as easy storage, cost-effectiveness, high sensitivity, and outstanding stability, Co4N NWs demonstrate the potential for replacing noble-metal-based peroxidase mimetics in a wide range of promising applications.

20.
CNS Neurosci Ther ; 22(8): 661-9, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27156691

RESUMO

BACKGROUND: Microglia-mediated inflammation may play an important role in the pathophysiology progression of neurodegenerative diseases, such as Parkinson's disease (PD), but the molecular mechanisms are poorly understood. AIMS: This study sought to determine whether E3 ubiquitin ligase c-Cbl plays a role in the brain inflammation and to explore the relevant molecular mechanism. METHODS: After BV2 microglial cells and c-Cbl-deficient mice were treated with lipopolysaccharide (LPS), neuroinflammation and microglial activation were evaluated by immunohistochemistry, ELISA and Western blot. We further investigated the possible mechanism of c-Cbl in regulating microglial activation. RESULTS: Here, we showed that the E3 ubiquitin ligase c-Cbl had high expression in brain tissues including substantia nigra pars compacta (SNc), striatum and hippocampus, and it was abundantly expressed in microglia. Systemic LPS administration resulted in more severe microglial activation in CNS and increased expression of brain proinflammatory factors (TNF-α, IL-6, IL-1ß and MCP-1) in c-Cbl knockout mice than wild type mice (WT). Downregulation of c-Cbl expression with c-Cbl siRNA in BV-2 microglial cells demonstrated a more robust increase in the proinflammatory factors release and NF-κB p65 nuclear translocation than that in control siRNA. Interestingly, Akt phosphorylation induced by LPS was also significantly augmented after c-Cbl knockdown. Moreover, blockade of PI3K/Akt activation by LY294002 significantly reduced inflammation response and NF-κB p65 nuclear translocation. CONCLUSION: In sum, c-Cbl inhibits expression of LPS-stimulated proinflammatory cytokines and chemokines in microglia. We demonstrate an unprecedented role for c-Cbl in microglia-mediated neuroinflammation involving PI3K/Akt/NF-κB pathway.


Assuntos
Encefalite/enzimologia , Microglia/fisiologia , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-cbl/deficiência , Transdução de Sinais/fisiologia , Animais , Encéfalo/metabolismo , Encéfalo/patologia , Linhagem Celular Transformada , Citocinas/genética , Citocinas/metabolismo , Modelos Animais de Doenças , Encefalite/etiologia , Encefalite/patologia , Inibidores Enzimáticos/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/genética , Lipopolissacarídeos/farmacologia , Camundongos , Camundongos Knockout , Microglia/efeitos dos fármacos , NF-kappa B/metabolismo , Nitritos/metabolismo , Fosforilação/efeitos dos fármacos , Fosforilação/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-cbl/genética , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Transdução de Sinais/efeitos dos fármacos
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