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1.
Mar Pollut Bull ; 196: 115632, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37826908

RESUMO

Spatial distributions of dissolved and particulate dimethylsulfoxide (DMSOd and DMSOp) were investigated off the northern Antarctic Peninsula during the austral summer of 2018, an ecologically and climatically important region of the world. In the upper waters, DMSOd was concentrated in the ice-melt zone because DMSO functions physiologically as an intracellular osmolyte and cryoprotectant. DMSOd concentrations had a weak positive correlation with temperature but a negative correlation with nutrients. This highlighted the importance of temperature-dependent biological activities and photolysis in DMSOd production and the important role of the intracellular antioxidation system in phytoplankton cells. The decrease of average DMSOp:Chl-a ratios in upper waters from west to east, along with decreasing temperatures and increasing diatoms proportions in the phytoplankton, illustrates how seawater DMSO production capacities depend on ambient temperatures and the composition of phytoplankton assemblages. DMSOp were accumulated in deep waters through bio-debris accumulation and microbial activity.


Assuntos
Dimetil Sulfóxido , Água do Mar , Regiões Antárticas , Estações do Ano , Fitoplâncton/fisiologia
2.
Cutan Ocul Toxicol ; 42(4): 213-218, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37417939

RESUMO

PURPOSE: This study aimed to investigate the early effects of intravitreal anti-vascular endothelial growth factor (anti-VEGF) agents on the cornea and visual acuity in patients with diabetic retinopathy (DR). METHODS: This retrospective study enrolled patients who were administered conbercept or ranibizumab to treat DR. Fundus photograph, fluorescein angiograph, and optical coherence tomography were preoperatively performed. The patients were classified into two groups: nonproliferative DR (NPDR) and PDR. Best-corrected visual acuity (BCVA), specular microscopy, central corneal thickness (CCT), and intraocular pressure were obtained before injection and at 1 day and 7 days after injection. The effects of anti-VEGF agents on BCVA and CCT were compared between the groups receiving conbercept and ranibizumab and between NPDR and PDR eyes. RESULTS: A total 38 eyes (30 patients) were enrolled in this study. Twenty-one eyes received conbercept, and 17 eyes received ranibizumab. Twenty eyes were classified as NPDR and 18 eyes as PDR. No significant differences were found between the groups receiving conbercept and ranibizumab in the increase in BCVA nor in the increase of CCT at 1 day and 7 days after injection. As compared with NPDR eyes, PDR eyes demonstrated a significantly greater increase in CCT (-5.3 ± 3.7 vs. 6.5 ± 2.9 µm, P = 0.02 < 0.05) but not in BCVA (P = 0.33) at 1 day after injection. At 7 days after injection, no significant differences were found in the increase in BCVA nor in the increase of CCT between NPDR eyes and PDR eyes. CONCLUSION: Intravitreal administration of anti-VEGF agents could cause a small but significant greater increase in CCT in PDR than in NPDR eyes in the early period. In patients with DR, no significant difference was found between conbercept and ranibizumab in the early effects on the visual acuity nor in the cornea.


Assuntos
Diabetes Mellitus , Retinopatia Diabética , Humanos , Ranibizumab/uso terapêutico , Inibidores da Angiogênese/uso terapêutico , Estudos Retrospectivos , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular , Córnea , Tomografia de Coerência Óptica , Acuidade Visual , Injeções Intravítreas , Diabetes Mellitus/tratamento farmacológico
3.
J Colloid Interface Sci ; 638: 709-718, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-36780851

RESUMO

Among many supercapacitor electrode materials, carbon materials are widely used due to their large specific surface area, good electrical conductivity and high economic efficiency. However, carbon-based supercapacitors face the challenges of low energy density and limited operating environment. This work reports a facile self-assembled method to prepare three-dimensional carbon nanotubes/reduced graphene oxide (CNTs/rGO) aerogel material, which was applied as both positive and negative electrodes in a symmetric superacapacitor. The fabricated supercapacitor exhibited prominent capacitive performance not only at room temperature, but also at extreme temperatures (-20 âˆ¼ 80 °C). The specific capacitances of the symmetric supercapacitors based on CNTs/rGO at a weight ratio of 2:5 respectively reached 107.8 and 128.2 F g-1 at 25 °C and 80 °C with KOH as the electrolyte, and 80.0 and 144.6 F g-1 at -20 °C and 60 °C with deep eutectic solvent as the electrolyte. Notably, the capacitance retention and coulombic efficiency of the assembled supercapacitors remained almost unchanged after 20,000 cycles of charge/discharge test over a wide temperature range. The work uncovered a possibility for the development of high-performance supercapacitors flexibly operated at extreme temperatures.

4.
Nat Prod Res ; 37(8): 1300-1309, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34758696

RESUMO

Euphorfinoids A and B (1 and 2), a pair of ent-atisane diterpenoid epimers with a vicinal 2,3-diol moiety, together with four known analogues (3-6), were isolated from the roots of wild Euphorbia fischeriana. Their structures were elucidated by spectroscopic analysis, including extensive NMR, HR-ESIMS, NMR calculations, X-ray diffraction, and comparison with structurally related known analogues. Our bioassays have established that compound 1 displayed moderate anti-proliferative effects on Hcc1806 cell line with IC50 15.53 ± 0.21 µM, and compound 5 showed remarkable inhibitory effects against AChE with IC50 32.56 ± 2.74 µM by an in vitro screened experiment.


Assuntos
Antineoplásicos Fitogênicos , Diterpenos , Euphorbia , Euphorbia/química , Antineoplásicos Fitogênicos/química , Diterpenos/química , Linhagem Celular Tumoral , Raízes de Plantas/química , Estrutura Molecular
5.
Int Ophthalmol ; 42(12): 3941-3950, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35776391

RESUMO

PURPOSE: Henle's fiber layer (HFL) is hyporeflective and indistinct on pupil-centered optical coherence tomography (OCT). However, a small area of HFL is also found to be hyperreflective on pupil-centered OCT. This study characterized the hyperreflective HFL of healthy eyes on pupil-centered OCT and investigated the possible physiological and functional relationship of hyperreflective HFL. METHODS: Subjects with different degrees of ametropia underwent a complete ophthalmologic examination, including binocular function by synoptophore and Titmus test, ocular axial length, refractions, and pupil-centered OCT angiography coupled with OCT. The area of hyperreflective HFL was manually plotted and calculated using the Optovue AngioVue system technology. The possible ocular physiological and functional relationship with the area of hyperreflective HFL was investigated. RESULTS: A total of 111 subjects (222 eyes) without other ocular diseases were enrolled, of which 164 eyes (74%) presented hyperreflective HFL. The average area of hyperreflective HFL was 0.71 ± 0.07 mm2. The area of hyperreflective HFL was significantly related to spherical diopters (P = 0.032). The average binocular area of hyperreflective HFL was 1.38 ± 0.17 mm2. The binocular area of hyperreflective HFL was significantly related to the angle of superposition and far stereoacuity (P = 0.013 and 0.038, respectively). CONCLUSION: Most healthy eyes present a small area of hyperreflective HFL, which might be due to alternation of the orientation of some Henle fibers by ametropia during the development of visual function postpartum. The small area of hyperreflective HFL may serve as a marker in identifying the boundary of HFL on OCT.


Assuntos
Erros de Refração , Tomografia de Coerência Óptica , Feminino , Humanos , Tomografia de Coerência Óptica/métodos , Pupila , Retina , Acuidade Visual
6.
Nutrients ; 14(8)2022 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-35458198

RESUMO

Black tea was reported to alter the microbiome populations and metabolites in diet-induced obese mice and displays properties that prevent obesity, but the underlying mechanism of the preventative effect of black tea on high-fat diet (HFD) induced obesity has not been elucidated. Epigenetic studies are a useful tool for determining the relationship between obesity and environment. Here, we show that the water extract of black tea (Lapsang souchong, LS) reverses HFD-induced gut dysbiosis, alters the tissue gene expression, changes the level of a major epigenetic modification (DNA methylation), and prevents obesity in HFD feeding mice. The anti-obesity properties of black tea are due to alkaloids, which are the principal active components. Our data indicate that the anti-obesity benefits of black tea are transmitted via fecal transplantation, and the change of tissue gene expression and the preventative effects on HFD-induced obesity in mice of black tea are dependent on the gut microbiota. We further show that black tea could regulate the DNA methylation of imprinted genes in the spermatozoa of high-fat diet mice. Our results show a mechanistic link between black tea, changes in the gut microbiota, epigenetic processes, and tissue gene expression in the modulation of diet-induced metabolic dysfunction.


Assuntos
Camellia sinensis , Microbioma Gastrointestinal , Animais , Dieta Hiperlipídica/efeitos adversos , Expressão Gênica , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Obesidade/etiologia , Obesidade/prevenção & controle , Chá
7.
J Agric Food Chem ; 70(14): 4418-4433, 2022 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-35347990

RESUMO

A chemical study on the epidermis of cultivated edible mushroom Wolfiporia cocos resulted in the isolation and identification of 46 lanostane triterpenoids, containing 17 new compounds (1-17). An experimental determination of their anti-inflammatory activity showed that poricoic acid GM (39) most strongly inhibited NO production in LPS-induced RAW264.7 murine macrophages with an IC50 value at 9.73 µM. Furthermore, poricoic acid GM induced HO-1 protein expression and inhibited iNOS and COX2 protein expression as well as the release of PGE2, IL-1ß, IL-6, TNF-α, and reactive oxygen species (ROS) in LPS-induced RAW264.7 cells. Mechanistically, poricoic acid GM suppressed the phosphorylation of the IκBα protein, which prevented NF-κB from entering the nucleus to lose transcriptional activity and inhibited the dissociation of Keap1 from Nrf2, thereby activating Nrf2 into the nucleus to regulate antioxidant genes. Furthermore, the MAPK signaling pathway may play a significant role in poricoic acid GM-induced elimination of inflammation. This work further confirms that lanostane triterpenoids are key ingredients responsible for the anti-inflammatory properties of the edible medicinal mushroom W. cocos.


Assuntos
Triterpenos , Wolfiporia , Animais , Anti-Inflamatórios/farmacologia , Epiderme/metabolismo , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Lipopolissacarídeos/farmacologia , Camundongos , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , NF-kappa B/genética , NF-kappa B/metabolismo , Células RAW 264.7 , Triterpenos/química , Triterpenos/farmacologia , Wolfiporia/química
8.
Bioorg Chem ; 116: 105395, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34628224

RESUMO

Seven new triterpenoids including two cycloartanes (1-2), a lanostane (3), a tirucallane (4), a dammarane (5), an ursane (6), and an oleanane (7), along with nineteen known triterpenoids (8-26), have been obtained from the roots of Euphorbia fischeriana. Their structures were established by NMR, HRESIMS, single-crystal X-ray diffraction analysis, Mosher's method, NMR calculations, ECD analysis, and comparison with structurally related known analogues. Among them, compounds 1 and 8 were a pair of cycloartane-type triterpenoids epimers. Our bioassays have established that compounds 1-5 and 10 displayed moderate cytotoxic effects, and the structure-activity relationships of cycloartane-type triterpenoids (CTTs) were further examined. Notably, some triterpenoids displayed moderate inhibitory effects against AChE by an in vitro screened experiment. Triterpenoid 7 (Euphorfistrine G, ETG) displayed the potent inhibitory effect with IC50 = 2.45 and Ki = 2.30 µM (inhibition kinetic). And, in silico docking analyses have been performed to investigate the inhibitory mechanism of compound 7.


Assuntos
Acetilcolinesterase/metabolismo , Antineoplásicos Fitogênicos/farmacologia , Inibidores da Colinesterase/farmacologia , Euphorbia/química , Triterpenos/farmacologia , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Inibidores da Colinesterase/química , Inibidores da Colinesterase/isolamento & purificação , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Modelos Moleculares , Estrutura Molecular , Relação Estrutura-Atividade , Triterpenos/química , Triterpenos/isolamento & purificação
11.
Invest Ophthalmol Vis Sci ; 62(1): 4, 2021 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-33393970

RESUMO

Purpose: Endophthalmitis models have reported the virulent role of Panton-Valentine leucocidin (PVL) secreted by Staphylococcus aureus on the retina. PVL targets retinal ganglion cells (RGCs), expressing PVL membrane receptor C5aR. Interactions between PVL and retinal cells lead to glial activation, retinal inflammation, and apoptosis. In this study, we explored oxidative stress and retinal neurotransmitters in a rabbit retinal explant model incubated with PVL. Methods: Reactive oxygen species (ROS) production in RGCs has been assessed with fluorescent probes and immunohistochemistry. Nuclear magnetic resonance (NMR) spectroscopy quantified retinal concentrations of antioxidant molecules and neurotransmitters, and concentrations of neurotransmitters released in the culture medium. Quantifying the expression of some pro-inflammatory and anti-inflammatory factors was performed using RT-qPCR. Results: PVL induced a mitochondrial ROS production in RGCs after four hours' incubation with the toxin. Enzymatic sources of ROS, involving nicotinamide adenine dinucleotide phosphate-oxidase and xanthine oxidase, were also activated after four hours in PVL-treated retinal explants. Retinal antioxidants defenses, that is, glutathione, ascorbate and taurine, decreased after two hours' incubation with PVL. Glutamate retinal concentrations and glutamate release in the culture medium remained unaltered in PVL-treated retinas. GABA, glycine, and acetylcholine (Ach) retinal concentrations decreased after PVL treatment. Glycine release in the culture medium decreased, whereas Ach release increased after PVL treatment. Expression of proinflammatory and anti-inflammatory cytokines remained unchanged in PVL-treated explants. Conclusions: PVL activates oxidative pathways and alters neurotransmitter retinal concentrations and release, supporting the hypothesis that PVL could induce a neurogenic inflammation in the retina.


Assuntos
Toxinas Bacterianas/farmacologia , Exotoxinas/farmacologia , Leucocidinas/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Receptor da Anafilatoxina C5a/metabolismo , Células Ganglionares da Retina/efeitos dos fármacos , Staphylococcus aureus/química , Acetilcolina/metabolismo , Animais , Células Cultivadas , Meios de Cultura , Citocinas/metabolismo , Corantes Fluorescentes , Glicina/metabolismo , Espectroscopia de Ressonância Magnética , Microscopia de Fluorescência , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , NADP/metabolismo , Coelhos , Reação em Cadeia da Polimerase em Tempo Real , Células Ganglionares da Retina/metabolismo , Xantina Oxidase/metabolismo , Ácido gama-Aminobutírico/metabolismo
12.
Retina ; 41(2): 309-316, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32404843

RESUMO

PURPOSE: To assess the frequency of macular cysts (MCs) in retinal detachment treated with silicone oil and evaluate their impact on visual acuity and macular vascularization using optical coherence tomography-angiography. METHODS: Forty-three eyes of 41 patients treated with silicone oil for retinal detachment were retrospectively studied. Best-corrected visual acuity and 6- × 6-mm optical coherence tomography-angiography examination at least 3 months after silicone oil removal were reviewed. In eyes with MCs, cyst area was measured on the en face optical coherence tomography-angiography image using ImageJ. Density of superficial capillary plexus and area of superficial foveal avascular zone were generated by the optical coherence tomography-angiography. Density of deep capillary plexus and deep foveal avascular zone area were measured using ImageJ. RESULTS: Twenty-five eyes (58%) presented with MCs. Cysts were exclusively located in the inner nuclear layer in 60% of cases. Mean best-corrected visual acuity in the MC group was lower than that of the non-MC group (P = 0.012). Macular cyst area negatively correlated with best-corrected visual acuity (P = 0.0201). Density of superficial capillary plexus was higher in the MC group (P < 0.0001), whereas area of superficial foveal avascular zone was lower (P < 0.0001). Macular cyst area negatively correlated with density of deep capillary plexus (P < 0.001). CONCLUSION: The incidence of INL-MCs after silicone oil removal is high. These are associated with impaired vision and macular vascular remodeling. We highlight their similarity with the "retrograde maculopathy" phenomenon.


Assuntos
Tamponamento Interno/métodos , Macula Lutea/patologia , Descolamento Retiniano/diagnóstico , Vasos Retinianos/patologia , Óleos de Silicone/farmacologia , Remodelação Vascular , Baixa Visão/etiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Angiofluoresceinografia/métodos , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Descolamento Retiniano/fisiopatologia , Descolamento Retiniano/cirurgia , Vasos Retinianos/fisiopatologia , Estudos Retrospectivos , Fatores de Tempo , Tomografia de Coerência Óptica/métodos , Baixa Visão/fisiopatologia , Acuidade Visual , Adulto Jovem
13.
Am J Ophthalmol ; 224: 18-29, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33285138

RESUMO

PURPOSE: To determine the mechanism behind macular bulge height increase in eyes with dome-shaped macula (DSM). DESIGN: Retrospective, observational case series. METHODS: Eyes presenting with DSM followed up for a minimum of 1 year were examined using ocular biometry and spectral-domain optical coherence tomography at baseline and at end of follow-up. Axial length (AL), DSM bulge height, and central and peripheral choroidal thickness (nasal, temporal, superior, and inferior quadrants) were reported. Eyes were categorized into 2 groups for comparison: the "mini-DSM" group (DSM < 100 µm) and the "classic" DSM group (DSM > 100 µm). RESULTS: Fifty-eight eyes (33 patients) were studied: 32 (55%) were classic DSM and 26 (45%) mini-DSM. During the mean follow-up of 51.76 ± 36.01 months, mean AL increased from 26.99 ± 2.94 mm to 27.12 ± 3.09 mm (P = .010) and mean macular bulge height increased from 235.88 ± 282.47 µm to 262.34 ± 317.15 µm (P < .001). DSM height change was significantly higher than AL change (P < .001). Mean peripheral choroidal thickness significantly decreased nasally (P = .008), temporally (P = .026), and inferiorly (P < .001). Mini-DSM eyes exhibited shorter AL (26.17 vs 27.66 mm; P = .027), greater visual acuity (0.169 vs 0.437 logMAR; P = .002), and fewer macular complications compared to classic DSM eyes. CONCLUSIONS: Macular bulge increase in DSM is associated with eye elongation and overall thinning of the peripheral choroid. DSM might result from differential elongation of the eye predominant in the peri-dome region. Mini-DSM (ie, inferior to 100 µm) are characterized by slower evolution, better visual prognosis, and fewer complications compared to "classic" DSM.


Assuntos
Comprimento Axial do Olho/patologia , Macula Lutea/patologia , Doenças Retinianas/etiologia , Adulto , Idoso , Biometria , Corioide/patologia , Dilatação Patológica/diagnóstico por imagem , Dilatação Patológica/etiologia , Dilatação Patológica/fisiopatologia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Miopia Degenerativa/complicações , Doenças Retinianas/diagnóstico por imagem , Doenças Retinianas/fisiopatologia , Estudos Retrospectivos , Microscopia com Lâmpada de Fenda , Tomografia de Coerência Óptica , Acuidade Visual/fisiologia
14.
Ophthalmologica ; 243(2): 129-135, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31775139

RESUMO

PURPOSE: Dome-shaped macula (DSM) is characterized by an inward bulge in the macula, often associated with a myopic staphyloma. One complication of DSM is particularly studied: foveolar serous retinal detachment (SRD). This study analyzed the variations of optical coherence tomography angiography (OCT-A) decorrelation signal in cases of DSM with and without SRD. METHODS: This was a retrospective study including twenty height eyes presenting with DSM. OCT-A scans were recorded, and the intensity of the choroidal decorrelation signal was quantified to analyze choroidal blood flow (CBF) in central, temporal, and nasal macular areas. The size of retinal pigment epithelium (RPE) atrophy was evaluated. RESULTS: CBF in the central area was significantly greater in the SRD group than in the no-SRD group (7.00 × 105 vs. 2.58 × 105) (p = 0.0049). CBF appeared decreased in the subfoveal area compared with the periphery for patients without SRD (p = 0.0107). The size of RPE atrophy was 0.762 optic disc area ±0.87. RPE atrophy correlated very significantly with CBF (p = 0.0012). CONCLUSION: A greater retrofoveolar CBF intensity is associated with the presence of SRD. These changes could reflect variations of CBF, and may represent a potential explanation for the pathogenesis of SRD in DSM.


Assuntos
Corioide/irrigação sanguínea , Angiofluoresceinografia/métodos , Macula Lutea/patologia , Fluxo Sanguíneo Regional/fisiologia , Descolamento Retiniano/diagnóstico , Tomografia de Coerência Óptica/métodos , Acuidade Visual , Corioide/diagnóstico por imagem , Feminino , Fundo de Olho , Humanos , Macula Lutea/fisiopatologia , Masculino , Pessoa de Meia-Idade , Descolamento Retiniano/fisiopatologia , Estudos Retrospectivos
15.
Chinese Journal of School Health ; (12): 352-355, 2020.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-819384

RESUMO

Objective@#To understand the concern of freshmen with different characteristics on sexual knowledge in Sichuan province and to provide evidence for comprenensive sex education in colleges.@*Methods@#A survey was conducted among 2 532 freshmen from 13 universities in Sichuan Province in September 2018. Attention to specific sexual knowledge among students with different characteristics was analyzed.@*Results@#Sexual knowledge that the freshmen concerned included partner communication (39.25%~55.10%), STD and AIDS (37.78%~44.85%) and gender equality (33.33%~43.34%). Logistic regression results showed that male students payed more attention to partner communication(OR=0.77,95%CI=0.65-0.91), masturbation (OR=0.36,95%CI=0.27-0.47) and sexual minorities (OR=0.61,95%CI=0.41-0.90), while female students payed more attention to gender equality (OR=1.31,95%CI=1.10-1.57), sexual harassment and violence (OR=1.65,95%CI=1.37-1.98). Rural students pay. more attention to partner communication (OR=0.79,95%CI=0.65-0.94), while urban students pay. more attention to masturbation (OR=1.50,95%CI=1.08-2.08), sexual harassment and sexual violence (OR=1.30,95%CI=1.07-1.58). Students who had sex were more concerned about contraception and unwanted pregnancy than those who had not (OR=0.53,95%CI=0.39-0.72). Sexual minority students were more concerned about topic of sexual minorities than heterosexual students (OR=3.50,95%CI=2.30-5.33).@*Conclusion@#College freshmen with different characteristics varied in their concern on sexual knowledge, which is related to their needs. It is suggested that schools set up comprehensive education courses according to the needs of students, the content of sex education knowledge can be focused, and carry out comprehensive and targeted sex education.

16.
Toxins (Basel) ; 10(11)2018 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-30400375

RESUMO

: Panton-Valentine leukocidin (PVL) retinal intoxication induces glial activation and inflammatory response via the interaction with retinal neurons. In this study, rabbit retinal explant was used as a model to study neuronal and glial consequences of PVL intoxication. Retinal explants were treated with different concentrations of PVL. PVL location and neuronal and glial changes were examined using immunohistochemistry. Some inflammatory factors were quantified using RT-qPCR at 4 and 8 h. These results were compared with those of control explants. PVL co-localized rapidly with retinal ganglion cells and with horizontal cells. PVL induced Müller and microglial cell activation. Retinal structure was altered and some amacrine and microglial cells underwent apoptosis. Glial activation and cell apoptosis increased in a PVL concentration- and time-dependent manner. IL-6 and IL-8 expression increased in PVL-treated explants but less than in control explants, which may indicate that other factors were responsible for glial activation and retinal apoptosis. On retinal explants, PVL co-localized with neuronal cells and induced glial activation together with microglial apoptosis, which confirms previous results observed in in vivo model. Rabbit retinal explant seems to be suitable model to further study the process of PVL leading to glial activation and retinal cells apoptosis.


Assuntos
Toxinas Bacterianas/toxicidade , Exotoxinas/toxicidade , Leucocidinas/toxicidade , Neuroglia/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Animais , Células Cultivadas , Mediadores da Inflamação/metabolismo , Neuroglia/metabolismo , Neuroglia/patologia , Neurônios/metabolismo , Neurônios/patologia , Coelhos
17.
Phytochemistry ; 152: 22-28, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29715600

RESUMO

Human kidney-type glutaminase (KGA) is an important target that is often over expressed in many cancer cells but very few effective inhibitors of this enzyme have yet reached clinical trials. Caudatan A and caudatan B, two undescribed tetracyclic flavans with an unusual ether bond between the C-4 and C-2' were isolated from the roots of Ohwia caudata (Thunb.) H.Ohashi. Caudatan A exhibited stronger inhibitory activity and caudatan B showed moderate effect from the results of inhibitory activities evaluations on KGA. The molecular docking and primary structure-activity relationship analysis revealed that the less steric hindrance at ring A was necessary to the effect. Therefore, combined its better solubility than that of bis-2-(5-phenylacetimido-1,2,4-thiadiazol-2-yl)ethyl sulfide (BPTES), caudatan A might be the potential candidate as the inhibitor of KGA for further studies.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Inibidores Enzimáticos/farmacologia , Flavonoides/farmacologia , Glutaminase/antagonistas & inibidores , Rim/enzimologia , Animais , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/isolamento & purificação , Inibidores Enzimáticos/química , Inibidores Enzimáticos/isolamento & purificação , Flavonoides/química , Flavonoides/isolamento & purificação , Glutaminase/isolamento & purificação , Glutaminase/metabolismo , Humanos , Simulação de Acoplamento Molecular , Raízes de Plantas/química , Ratos , Relação Estrutura-Atividade
18.
Sci Rep ; 8(1): 2953, 2018 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-29440661

RESUMO

Experimental models have established Panton-Valentine leukocidin (PVL) as a potential critical virulence factor during Staphylococcus aureus endophthalmitis. In the present study, we aimed to identify retinal cell targets for PVL and to analyze early retinal changes during infection. After the intravitreous injection of PVL, adult rabbits were euthanized at different time points (30 min, 1, 2, 4 and 8 h). PVL location in the retina, expression of its binding receptor C5a receptor (C5aR), and changes in Müller and microglial cells were analyzed using immunohistochemistry, Western blotting and RT-qPCR. In this model of PVL eye intoxication, only retinal ganglion cells (RGCs) expressed C5aR, and PVL was identified on the surface of two kinds of retinal neural cells. PVL-linked fluorescence increased in RGCs over time, reaching 98% of all RGCs 2 h after PVL injection. However, displaced amacrine cells (DACs) transiently colocalized with PVL. Müller and microglial cells were increasingly activated after injection over time. IL-6 expression in retina increased and some microglial cells underwent apoptosis 4 h and 8 h after PVL infection, probably because of abnormal nitrotyrosine production in the retina.


Assuntos
Células Amácrinas/metabolismo , Apoptose , Toxinas Bacterianas/metabolismo , Exotoxinas/metabolismo , Leucocidinas/metabolismo , Microglia/citologia , Células Ganglionares da Retina/metabolismo , Animais , Transporte Biológico , Regulação da Expressão Gênica , Interleucina-6/metabolismo , Coelhos , Tirosina/análogos & derivados , Tirosina/metabolismo
19.
J Mater Chem B ; 5(2): 289-295, 2017 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-32263547

RESUMO

A novel ratiometric probe (RCP) for -OCl was developed based on the fluorescence resonance energy transfer (FRET) platform. The probe was constructed by integrating the coumarin moiety (FRET donor) with the rhodamine moiety (FRET acceptor). Upon treatment with -OCl, the coumarin emission at 483 nm decreased and the rhodamine emission at 570 nm increased, enabling the probe to provide accurate detection of -OCl (in the concentration range of 0-50 µM). The probe exhibited brilliant selectivity and sensitivity, rapid response and low cytotoxicity. More importantly, the introduction of the quaternized pyridine moiety can not only manage to increase the solubility, but also achieve mitochondria-targeting. The probe was applied successfully to imaging endogenous -OCl in mitochondria, highlighting its potential applications in bioanalysis.

20.
Bioorg Med Chem Lett ; 26(12): 2874-2879, 2016 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-27133595

RESUMO

With the aim of finding more potential anti-gout compounds from natural resources, a phytochemical study on the leaves of Stauntonia brachyanthera was carried out, which led to the isolation of 11 nor-oleanane triterpenoids, including 4 new ones. Their structures were determined by the comprehensive 1D, 2D NMR, HRMS, and HPLC analysis after acid hydrolysis. Brachyantheraoside B4 (3) and 3-O-α-l-rhamnopyranosyl-(1→2)-α-l-arabinopyranosyl-30-norolean-12,20(29)-dien-28-oic acid (8) exhibited significant inhibitory activities on xanthine oxidase with IC50 values of 0.20 and 18.5µM, respectively. Brachyantheraoside C2 (2) also showed moderate effects on XO. A primary structure-activity relationship was also summarized, which revealed the anti-gout abilities of three nor-oleanane triterpenoids and their potential possibilities as the candidate compounds for the treatment of gout. The discovery of nor-oleanane triterpenoids also widens people's idea for the study of anti-gout agents and promotes the comprehensive development of S. brachyanthera.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Gota/tratamento farmacológico , Magnoliopsida/química , Ácido Oleanólico/análogos & derivados , Folhas de Planta/química , Relação Dose-Resposta a Droga , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/isolamento & purificação , Humanos , Estrutura Molecular , Ácido Oleanólico/química , Ácido Oleanólico/isolamento & purificação , Ácido Oleanólico/farmacologia , Relação Estrutura-Atividade
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