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1.
Exp Eye Res ; 244: 109935, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38763352

RESUMO

Müller glia and microglia are capable of phagocytosing fragments of retinal cells in response to retinal injury or degeneration. However, the direct evidence for their mutual interactions between Müller glia and microglia in the progression of retinal degeneration (RD) remains largely unclear. This study aims to construct a progressive RD mouse model and investigate the activated pattern of Müller glia and the interplay between Müller glia and microglia in the early stage or progression of RD. A Prohibitin 2 (Phb2) photoreceptor-specific knockout (RKO) mouse model was generated by crossing Phb2flox/flox mice with Rhodopsin-Cre mice. Optical Coherence Tomography (OCT), histological staining, and Electroretinography (ERG) assessed retinal structure and function, and RKO mice exhibited progressive RD from six weeks of age. In detail, six-week-old RKO mice showed no significant retinal impairment, but severe vision dysfunction and retina thinning were shown in ten-week-old RKO mice. Furthermore, RKO mice were sensitive to Light Damage (LD) and showed severe RD at an early age after light exposure. Bulk retina RNA-seq analysis from six-week-old control (Ctrl) and RKO mice showed reactive retinal glia in RKO mice. The activated pattern of Müller glia and the interplay between Müller glia and microglia was visualized by immunohistology and 3D reconstruction. In six-week-old RKO mice or light-exposed Ctrl mice, Müller glia were initially activated at the edge of the retina. Moreover, in ten-week-old RKO mice or light-exposed six-week-old RKO mice with severe photoreceptor degeneration, abundant Müller glia were activated across the whole retinas. With the progression of RD, phagocytosis of microglia debris by activated Müller glia were remarkably increased. Altogether, our study establishes a Phb2 photoreceptor-specific knockout mouse model, which is a novel mouse model of RD and can well demonstrate the phenotype of progressive RD. We also report that Müller glia in the peripheral retina is more sensitive to the early damage of photoreceptors. Our study provides more direct evidence for Müller glia engulfing microglia debris in the progression of RD due to photoreceptor Phb2 deficiency.


Assuntos
Células Ependimogliais , Microglia , Células Fotorreceptoras de Vertebrados , Proibitinas , Degeneração Retiniana , Animais , Camundongos , Modelos Animais de Doenças , Eletrorretinografia , Células Ependimogliais/metabolismo , Células Ependimogliais/patologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microglia/metabolismo , Microglia/patologia , Fagocitose/fisiologia , Células Fotorreceptoras de Vertebrados/patologia , Células Fotorreceptoras de Vertebrados/metabolismo , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Proteínas Repressoras/deficiência , Degeneração Retiniana/metabolismo , Degeneração Retiniana/patologia , Degeneração Retiniana/fisiopatologia , Tomografia de Coerência Óptica
2.
BMC Med ; 22(1): 18, 2024 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-38185665

RESUMO

BACKGROUND: Methadone maintenance treatment (MMT) has been implemented in China for nearly two decades, with a significant decrease in the number of participants in recent years. However, there is a lack of comprehensive research focusing on the long-term effectiveness in the context of this decline, especially from the perspectives of MMT participants themselves. This study aims to address this gap by examining the benefits and challenges experienced by long-term MMT participants in China, to uncover potential causes of the decrease in participant numbers and to improve the effectiveness of the program. METHODS: We conducted semi-structured interviews with 21 long-term MMT participants (treatment duration ≥ 5 years) recruited through purposive sampling from 6 MMT clinics in the Guangdong Province, China, between December 2021 and August 2022. Thematic analysis was employed to analyze the transcribed interviews. Two analysts independently coded the data, and a third researcher double-coded 20% of transcripts to ensure intercoder reliability. RESULTS: Overall, participants corroborated the notable decline in MMT participants during their long-term MMT, citing death, arrest, and self-perceived abstinence from heroin, as their perceived driving factors. They reported positive changes in their health, family relationships, and social functioning. However, they identified economic hardship as their greatest challenge associated with MMT, further exacerbated by other barriers including the conflict of clinic opening hours and working schedules, discrimination from employers, and COVID-19-related restrictions. Additionally, participants identified issues with dose adjustment and emergency treatment continuation. CONCLUSIONS: This study outlines the overall improvement in the quality of life of long-term MMT participants. However, it highlights the need for official guidelines for dose adjustment and emergency treatment continuation as well as the provision of health education, job referrals, and flexibility of clinic opening times to facilitate the return to society receiving participants. Establishing a follow-up mechanism for those receiving MMT is also recommended to prevent relapses to heroin and other illicit substances.


Assuntos
Heroína , Qualidade de Vida , Humanos , Reprodutibilidade dos Testes , China , Metadona/uso terapêutico
3.
Nat Commun ; 14(1): 3924, 2023 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-37400469

RESUMO

High-throughput experimentation (HTE) is an increasingly important tool in reaction discovery. While the hardware for running HTE in the chemical laboratory has evolved significantly in recent years, there remains a need for software solutions to navigate data-rich experiments. Here we have developed phactor™, a software that facilitates the performance and analysis of HTE in a chemical laboratory. phactor™ allows experimentalists to rapidly design arrays of chemical reactions or direct-to-biology experiments in 24, 96, 384, or 1,536 wellplates. Users can access online reagent data, such as a chemical inventory, to virtually populate wells with experiments and produce instructions to perform the reaction array manually, or with the assistance of a liquid handling robot. After completion of the reaction array, analytical results can be uploaded for facile evaluation, and to guide the next series of experiments. All chemical data, metadata, and results are stored in machine-readable formats that are readily translatable to various software. We also demonstrate the use of phactor™ in the discovery of several chemistries, including the identification of a low micromolar inhibitor of the SARS-CoV-2 main protease. Furthermore, phactor™ has been made available for free academic use in 24- and 96-well formats via an online interface.


Assuntos
COVID-19 , Humanos , SARS-CoV-2 , Software
4.
Cancer Med ; 12(4): 3987-3998, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36106610

RESUMO

BACKGROUND: This study aimed to better characterize the clinicopathologic characteristics, outcomes, and prognostic factors of AITL in China. METHODS: We retrospectively analyzed 312 patients with AITL enrolled between January 2011 and December 2020 from five institutions in China. RESULTS: The median age was 65 years, with 92.6% advanced stage, 59.7% elevated LDH, 46.1% anemia, and 44.0% hypergammaglobulinemia. The majority of patients (84.9%) received anthracycline-based regimens with or without etoposide, and only 6.1% underwent autologous stem cell transplantation following first remission. The 5-year OS and PFS estimates were 43.4% and 25.0% with no significant improvement of survival between patients treated during 2011-2015 and 2016-2020, respectively. Both the International Prognostic Index (IPI) and the prognostic index for PTCL, not otherwise specified (PIT), were predictive for OS. In multivariate analysis, age >70 years, elevated LDH, and albumin level <35 g/L were independent prognostic factors for OS. Combining these three factors, a novel prognostic model (the Chinese AITL score) was constructed, which stratified patients into low-, intermediate-, and high-risk groups, with 5-year OS rates of 69.0%, 41.5%, and 23.7%, respectively. This new model was successfully validated in an independent cohort. CONCLUSIONS: Patients with AITL were mainly treated with anthracycline-based regimens, and the outcomes were still unsatisfactory in China. Our novel prognostic model may improve our ability to identify patients at different risks for alternative therapies.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Linfadenopatia Imunoblástica , Linfoma de Células T Periférico , Humanos , Idoso , Prognóstico , Estudos Retrospectivos , Transplante Autólogo , Linfadenopatia Imunoblástica/terapia , Antraciclinas/uso terapêutico
6.
Nat Commun ; 12(1): 7327, 2021 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-34916512

RESUMO

The global disruption caused by the 2020 coronavirus pandemic stressed the supply chain of many products, including pharmaceuticals. Multiple drug repurposing studies for COVID-19 are now underway. If a winning therapeutic emerges, it is unlikely that the existing inventory of the medicine, or even the chemical raw materials needed to synthesize it, will be available in the quantities required. Here, we utilize retrosynthetic software to arrive at alternate chemical supply chains for the antiviral drug umifenovir, as well as eleven other antiviral and anti-inflammatory drugs. We have experimentally validated four routes to umifenovir and one route to bromhexine. In one route to umifenovir the software invokes conversion of six C-H bonds into C-C bonds or functional groups. The strategy we apply of excluding known starting materials from search results can be used to identify distinct starting materials, for instance to relieve stress on existing supply chains.


Assuntos
Antivirais/química , Tratamento Farmacológico da COVID-19 , Indóis/química , Software , Anti-Inflamatórios/química , Anti-Inflamatórios/uso terapêutico , Antivirais/uso terapêutico , Reposicionamento de Medicamentos , Humanos , Indóis/uso terapêutico , SARS-CoV-2/efeitos dos fármacos
7.
Angew Chem Int Ed Engl ; 60(52): 27293-27298, 2021 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-34669980

RESUMO

We have developed a deaminative-decarboxylative protocol to form new carbon(sp3 )-carbon(sp3 ) bonds from activated amines and carboxylic acids. Amines and carboxylic acids are ubiquitous building blocks, available in broad chemical diversity and at lower cost than typical C-C coupling partners. To leverage amines and acids for C-C coupling, we developed a reductive nickel-catalyzed cross-coupling utilizing building block activation as pyridinium salts and redox-active esters, respectively. Miniaturized high-throughput experimentation studies were critical to our reaction optimization, with subtle experimental changes such as order of reagent addition, composition of a binary solvent system, and ligand identity having a significant impact on reaction performance. The developed protocol is used in the late-stage diversification of pharmaceuticals while more than one thousand systematically captured and machine-readable reaction datapoints are reposited.

8.
Mol Med Rep ; 23(4)2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33649799

RESUMO

Cytoglobin (Cygb) is a globin molecule that is ubiquitously expressed in all tissues and has a protective role under oxidative stress. It has also been demonstrated to be effective in the treatment of alcoholic fatty liver disease (AFLD). In order to study the molecular mechanisms underlying its beneficial effects for the treatment of alcoholic liver, two­dimensional electrophoresis and mass spectrometric analysis were performed on serum and liver tissues from an in vivo rat model of AFLD. A total of 26 differentially expressed proteins were identified in the serum and 20 differentially expressed proteins were identified in liver specimens. Using online bioinformatics tools, it was indicated that these differentially expressed proteins were primarily associated with pathways including binding and uptake of ligands by scavenger receptors, response to corticosteroid, plasma lipoprotein remodeling, regulation of complement cascade, hydrogen peroxide catabolic process, as well as response to nutrient and monosaccharide. The present results suggested that recombinant human Cygb exerts its role in the treatment of AFLD primarily through affecting nutrient metabolism, monocarboxylic acid biosynthesis, regulation of glutathione expression, plasma lipoprotein remodeling and removal of metabolic waste from the blood.


Assuntos
Biologia Computacional/métodos , Citoglobina/farmacologia , Fígado Gorduroso Alcoólico/tratamento farmacológico , Fígado Gorduroso Alcoólico/metabolismo , Proteoma/efeitos dos fármacos , Proteômica/métodos , Proteínas Recombinantes/farmacologia , Animais , Citoglobina/genética , Modelos Animais de Doenças , Eletroforese em Gel Bidimensional , Humanos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Masculino , Proteoma/metabolismo , Ratos Wistar , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
9.
Synthesis (Stuttg) ; 52(10): 1478-1497, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-34349297

RESUMO

The 60-year history of sodium diisopropylamide (NaDA) is described herein. We review various preparations, solvent-dependent stabilities, and solution structures. Synthetic applications of NaDA reported to date are framed by a mechanism-driven approach, emphasizing selectivities when appropriate. We conclude with examples beyond metalation in which NaDA plays a central role and a few thoughts on where future applications could be focused.

10.
J Org Chem ; 84(17): 10892-10900, 2019 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-31414796

RESUMO

[2,3]-Sigmatropic rearrangements (Wittig rearrangements) of α-alkoxy oxazolidinone enolates are described. Whereas alkali metal enolates fail, owing to facile deacylation, boron enolates generated from di-n-butylboron triflate and triethylamine rearranged in good yields and high selectivities with exceptions noted. IR and NMR spectroscopies show the boron is chelated by the α-alkoxy group rather than the more distal oxazolidinone carbonyl in the complex and enolate. The rearrangement product contains a boron alkoxide that remains unchelated by either carbonyl. Optimization was guided by density functional theory computations, suggesting that valine-derived oxazolidinones would be superior to the phenylalanine-derived analogues.


Assuntos
Boro/química , Oxazolidinonas/química , Modelos Moleculares , Conformação Molecular , Estereoisomerismo
11.
Ophthalmic Res ; 62(2): 93-100, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31121579

RESUMO

PURPOSE: To evaluate the efficacy of intravitreal conbercept injections in patients with treatment-resistant neovascular age-related macular degeneration (nvAMD). METHODS: Retrospective review of patients with resistance (persistent exudation) to ranibizumab (0.5 mg) that were switched to treatment with 3 monthly intravitreal injections of conbercept (0.5 mg), followed by dosing on an as-needed basis. The demographic data, visual acuities, central retinal thickness (CRT), and the maximum pigment epithelial detachment (PED) height were reviewed. RESULTS: Outcomes observed in 34 eyes from 26 patients with a mean of 7.68 (range 6-14) previous ranibizumab injections were compiled. Twelve months after switching to conbercept, there were significant reductions of CRT (402.59 ± 163.85 vs. 473.18 ± 164.84 µm, p = 0.002) and maximum PED height (218.59 ± 106.89 vs. 295.32 ± 179.80 µm, p = 0.006) compared with the baseline. No statistical change in visual acuity logarithm of the minimal angle of resolution occurred after 12 months (0.68 ± 0.48 vs. 0.78 ± 0.63 letters, p = 0.17) despite 27 of 34 eyes (79.41%) remaining stable or having improvement visual acuity. CONCLUSIONS: Intravitreal injections of conbercept appear to be beneficial in patients with nvAMD who exhibit persistent fluid despite previous treatment with ranibizumab.


Assuntos
Inibidores da Angiogênese/administração & dosagem , Neovascularização de Coroide/tratamento farmacológico , Degeneração Macular/tratamento farmacológico , Proteínas Recombinantes de Fusão/administração & dosagem , Idoso , Idoso de 80 Anos ou mais , Neovascularização de Coroide/fisiopatologia , Feminino , Humanos , Injeções Intravítreas , Degeneração Macular/fisiopatologia , Masculino , Pessoa de Meia-Idade , Ranibizumab/uso terapêutico , Retina/patologia , Estudos Retrospectivos , Acuidade Visual/fisiologia
12.
Retina ; 39(7): 1353-1360, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29547454

RESUMO

PURPOSE: In this study, we aimed to evaluate the efficacy and safety of intravitreal conbercept in patients with treatment-naive neovascular age-related macular degeneration in real-life setting. METHODS: Three consecutive intravitreal injections of conbercept following a pro re nata protocol. The main outcomes were the changes of Early Treatment Diabetic Retinopathy Study best-corrected visual acuity and central retinal thickness between the baseline and the 12th month. RESULTS: Mean best-corrected visual acuity was improved from 39.39 ± 24.91 letters at the baseline to 44.26 ± 22.89 letters at the final follow-up (P < 0.001). At the 12th month, the proportion of optimal response was 43.48% compared with 36.96% of poor response and 19.56% of nonresponse. A mean central retinal thickness of 480.94 ± 178.47 µm at the baseline was significantly reduced to 366.33 ± 173.52 µm at the 12th month. Patients received a median of 5.32 intravitreal injections. At the 12th month, the mean change in best-corrected visual acuity of eyes with intraretinal cystoid fluid from the baseline was markedly lower than that of eyes without intraretinal cystoid fluid. No adverse events were attributed to conbercept. CONCLUSION: With 12-month follow-up, conbercept was proved to be an effective and safety treatment for patients with treatment-naive neovascular age-related macular degeneration in real-life setting.


Assuntos
Macula Lutea/patologia , Proteínas Recombinantes de Fusão/administração & dosagem , Acuidade Visual , Degeneração Macular Exsudativa/tratamento farmacológico , Idoso , China , Progressão da Doença , Relação Dose-Resposta a Droga , Feminino , Angiofluoresceinografia/métodos , Seguimentos , Fundo de Olho , Humanos , Injeções Intravítreas , Masculino , Estudos Retrospectivos , Tomografia de Coerência Óptica/métodos , Resultado do Tratamento , Degeneração Macular Exsudativa/diagnóstico
13.
J Am Chem Soc ; 141(1): 388-401, 2019 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-30462500

RESUMO

Oxazolidinone-based sodiated enolates (Evans enolates) were generated using sodium diisopropylamide (NaDA) or sodium hexamethyldisilazide (NaHMDS) in the presence of N,N,N',N'-tetramethylethylenediamine (TMEDA), ( R,R)- trans- N,N,N',N'-tetramethylcyclohexanediamine [( R,R)-TMCDA], or ( S,S)-TMCDA. 13C NMR spectroscopic analysis in conjunction with the method of continuous variations (MCV), x-ray crystallography, and density functional theory (DFT) computations revealed the enolates to be octahedral bis-diamine-chelated monomers. Rate and computational studies of an alkylation with allyl bromide implicate a bis-diamine-chelated-monomer-based transition structure. The sodiated Evans enolates form mixed dimers with NaHMDS, NaDA, or sodium 2,6-di- tert-butylphenolate, the reactivities of which are examined. Stereoselective quaternizations, aldol additions, and azaaldol additions are described.


Assuntos
Alcenos/química , Solventes/química , Alquilação , Cinética , Modelos Moleculares , Conformação Molecular , Oxazóis/química , Estereoisomerismo
14.
Medicine (Baltimore) ; 97(51): e13775, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30572531

RESUMO

BACKGROUND: Different antivascular endothelial growth factor (VEGF) monotherapy regimens and photodynamic therapy (PDT) combined with anti-VEGF therapy are available for patients with polypoidal choroidal vasculopathy (PCV). However, the comparative efficacy and safety of different anti-VEGF monotherapy regimens and combined therapy with PDT and anti-VEGF remains unknown. The aim of our study is to evaluate the efficacy and safety of anti-VEGF monotherapies and combined therapy in patients with PCV. METHODS: We will systematically search PubMed, Embase, and the Cochrane library for eligible studies. The Cochrane Collaboration's tool for assessing the risk of bias in a randomized trial and the ROBINS-I tool will be used to assess the risk of bias in the included studies. The primary outcome is the mean change in best corrected visual acuity from baseline. The secondary outcomes are the mean change in central retinal thickness from baseline and the number of serious adverse events. RESULTS: The result will generate a comprehensive suggestion for the treatment of PCV. CONCLUSION: The results of the network meta-analysis will be submitted in a peer-reviewed journal for publication. ETHICS AND DISSEMINATION: The study does not involve human subjects and requires no ethical approval or patient consent. The results of the network meta-analysis will be submitted in a peer-reviewed journal for publication and generate a comprehensive suggestion for the treatment of PCV.


Assuntos
Neovascularização de Coroide/tratamento farmacológico , Metanálise em Rede , Fotoquimioterapia/métodos , Revisões Sistemáticas como Assunto , Fator A de Crescimento do Endotélio Vascular/uso terapêutico , Humanos , Ensaios Clínicos Controlados não Aleatórios como Assunto , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento
15.
J Org Chem ; 82(14): 7595-7601, 2017 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-28686020

RESUMO

The soft enolization of an acylated oxazolidinone using di-n-butylboron triflate (n-Bu2BOTf) and trialkylamines and subsequent aldol addition was probed structurally and mechanistically using a combination of IR and NMR spectroscopies. None of the species along the reaction coordinate show a penchant for aggregating. Complexation of the acylated oxazolidinone by n-Bu2BOTf was too rapid to monitor, as was the subsequent enolization with Et3N (triethylamine). The preformed n-Bu2BOTf·Et3N complex, displaying muted Lewis acidity and affiliated tractable rates, reveals a rate-limiting complexation via a transition structure with a complicated counterion. n-Bu2BOTf·i-Bu3N bearing a hindered amine shifts the rate-limiting step to proton transfer. Rate studies show that the aldol addition with isobutyraldehyde occurs as proffered by others.


Assuntos
Compostos de Boro/síntese química , Cetonas/síntese química , Oxazolidinonas/química , Compostos de Boro/química , Cetonas/química , Conformação Molecular
16.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 47(6): 894-897, 2016 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-28598120

RESUMO

OBJECTIVES: To determine the characteristics and clinical significance of outer retinal tabulation (ORT) in wet age-related macular degeneration (wAMD) treated by anti-vascular endothelial growth factor (anti-VEGF) through optical coherence tomography (OCT). METHODS: The 35 wAMD patients with 39 ORT eyes treated by anti-VEGF were examined by OCT to determine the morphological features and evolution of the ORTs over time and their response to anti-VEGF. RESULTS: ORTs were located in the places that exudation or edema had happened in the outer nuclear layer of retina.38 ORTs remained stable on both quantity and morphology.One ORT became invisible temporarily and then reappeared. CONCLUSIONS: ORTs are reconstructed by photoreceptor cells that have survived after outer retina damages.There is no connection between anti-VEGF treatment and ORT formation.


Assuntos
Retina/patologia , Tomografia de Coerência Óptica , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Degeneração Macular Exsudativa/tratamento farmacológico , Inibidores da Angiogênese/farmacologia , Humanos , Estudos Retrospectivos
17.
J Org Chem ; 78(9): 4551-7, 2013 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-23578212

RESUMO

A copper-catalyzed decarboxylative coupling reaction of potassium alkynyl carboxylates with 1,1-dibromo-1-alkenes was developed for the synthesis of unsymmetrical 1,3-diyne and 1,3,5-triyne derivatives. Diverse aryl, alkenyl, alkynyl, and alkyl substituted 1,1-dibromo-1-alkenes can react smoothly with aryl and alkyl substituted propiolates to produce unsymmetrical 1,3-diynes and 1,3,5-triynes with high selectivity and good functional group compatibility.


Assuntos
Alcenos/química , Alcinos/síntese química , Ácidos Carboxílicos/química , Cobre/química , Hidrocarbonetos Bromados/química , Alcinos/química , Técnicas de Química Sintética , Descarboxilação , Estrutura Molecular , Compostos Organometálicos/química , Fenantrolinas/química
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