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1.
Nat Prod Bioprospect ; 14(1): 26, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38691189

RESUMO

Seven undescribed compounds, including three flavones (1-3), one phenylpropanoid (19), three monoaromatic hydrocarbons (27-29), were isolated from the twigs of Mosla chinensis Maxim together with twenty-eight known compounds. The structures were characterized by HRESIMS, 1D and 2D NMR, and ECD spectroscopic techniques. Compound 20 displayed the most significant activity against A/WSN/33/2009 (H1N1) virus (IC50 = 20.47 µM) compared to the positive control oseltamivir (IC50 = 6.85 µM). Further research on the anti-influenza mechanism showed that compound 20 could bind to H1N1 virus surface antigen HA1 and inhibit the early attachment stage of the virus. Furthermore, compounds 9, 22, 23, and 25 displayed moderate inhibitory effects on the NO expression in LPS inducing Raw 264.7 cells with IC50 values of 22.78, 20.47, 27.66, and 30.14 µM, respectively.

2.
Planta ; 259(6): 131, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38652171

RESUMO

MAIN CONCLUSION: The anatomical structures of Carex moorcroftii roots showing stronger plasticity during drought had a lower coefficient of variation in cell size in the same habitats, while those showing weaker plasticity had a higher coefficient of variation. The complementary relationship between these factors comprises the adaptation mechanism of the C. moorcroftii root to drought. To explore the effects of habitat drought on root anatomy of hygrophytic plants, this study focused on roots of C. moorcroftii. Five sample plots were set up along a soil moisture gradient in the Western Sichuan Plateau to collect experimental materials. Paraffin sectioning was used to obtain root anatomy, and one-way ANOVA, correlation analysis, linear regression analysis, and RDA ranking were applied to analyze the relationship between root anatomy and soil water content. The results showed that the root transverse section area, thickness of epidermal cells, exodermis and Casparian strips, and area of aerenchyma were significantly and positively correlated with soil moisture content (P < 0.01). The diameter of the vascular cylinder and the number and total area of vessels were significantly and negatively correlated with the soil moisture content (P < 0.01). The plasticity of the anatomical structures was strong for the diameter and area of the vascular cylinder and thickness of the Casparian strip and epidermis, while it was weak for vessel diameter and area. In addition, there was an asymmetrical relationship between the functional adaptation of root anatomical structure in different soil moisture and the variation degree of root anatomical structure in the same soil moisture. Therefore, the roots of C. moorcroftii can shorten the water transport distance from the epidermis to the vascular cylinder, increase the area of the vascular cylinder and the number of vessels, and establish a complementary relationship between the functional adaptation of root anatomical structure in different habitats and the variation degree of root anatomical structure in the same habitat to adapt to habitat drought. This study provides a scientific basis for understanding the response of plateau wetland plants to habitat changes and their ecological adaptation strategies. More scientific experimental methods should be adopted to further study the mutual coordination mechanisms of different anatomical structures during root adaptation to habitat drought for hygrophytic plants.


Assuntos
Carex (Planta) , Secas , Ecossistema , Raízes de Plantas , Solo , Água , Raízes de Plantas/anatomia & histologia , Raízes de Plantas/fisiologia , China , Carex (Planta)/fisiologia , Carex (Planta)/anatomia & histologia , Água/fisiologia , Água/metabolismo , Adaptação Fisiológica
3.
Expert Rev Vaccines ; 23(1): 523-534, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38682812

RESUMO

BACKGROUND: Traditional vaccine development, often a lengthy and costly process of three separated phases. However, the swift development of COVID-19 vaccines highlighted the critical importance of accelerating the approval of vaccines. This article showcases a seamless phase 2/3 trial design to expedite the development process, particularly for multi-valent vaccines. RESEARCH DESIGN AND METHODS: This study utilizes simulation to compare the performance of seamless phase 2/3 design with that of conventional trial design, specifically by re-envisioning a 9-valent HPV vaccine trial. Across three cases, several key performance metrics are evaluated: overall power, type I error rate, average sample size, trial duration, the percentage of early stop, and the accuracy of dose selection. RESULTS: On average, when the experimental vaccine was assumed to be effective, the seamless design that performed interim analyses based solely on efficacy saved 555.73 subjects, shortened trials by 10.29 months, and increased power by 3.70%. When the experimental vaccine was less effective than control, it saved an average of 887.73 subjects while maintaining the type I error rate below 0.025. CONCLUSION: The seamless design proves to be a compelling strategy for vaccine development, given its versatility in early stopping, re-estimating sample sizes, and shortening trial durations.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Ensaios Clínicos Fase II como Assunto , Ensaios Clínicos Fase III como Assunto , Projetos de Pesquisa , Desenvolvimento de Vacinas , Humanos , Vacinas contra COVID-19/administração & dosagem , Vacinas contra COVID-19/imunologia , COVID-19/prevenção & controle , Desenvolvimento de Vacinas/métodos , Tamanho da Amostra , Vacinas contra Papillomavirus/administração & dosagem , Vacinas contra Papillomavirus/imunologia , Simulação por Computador
4.
Fitoterapia ; 170: 105670, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37690598

RESUMO

Verbena officinalis is used as a Chinese folk medicine for the treatment of rheumatism and bronchitis. Herein, four undescribed triterpenes, officinalisoids A-D (1-4), together with thirty-three known compounds (5-37) were isolated from the aerial parts of V. officinalis. The chemical structures of the new compounds were determined by spectrometric data interpretation using NMR, HRESIMS, IR and UV spectroscopy. Biological evaluation results revealed that compound 30 exhibited potential anti-inflammatory activity with IC50 value of 6.07 µM (CC50 > 50 µM) and compound 12 showed moderate anti-dengue virus activity with the IC50 value of 24.55 µM (CC50 > 50 µM).

5.
Infect Dis Poverty ; 11(1): 74, 2022 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-35768826

RESUMO

BACKGROUND: During the coronavirus disease 2019 (COVID-19) pandemic, seasonal influenza activity declined globally and remained below previous seasonal levels, but intensified in China since 2021. Preventive measures to COVID-19 accompanied by different epidemic characteristics of influenza in different regions of the world. To better respond to influenza outbreaks under the COVID-19 pandemic, we analyzed the epidemiology, antigenic and genetic characteristics, and antiviral susceptibility of influenza viruses in the mainland of China during 2020-2021. METHODS: Respiratory specimens from influenza like illness cases were collected by sentinel hospitals and sent to network laboratories in Chinese National Influenza Surveillance Network. Antigenic mutation analysis of influenza virus isolates was performed by hemagglutination inhibition assay. Next-generation sequencing was used for genetic analyses. We also conducted molecular characterization and phylogenetic analysis of circulating influenza viruses. Viruses were tested for resistance to antiviral medications using phenotypic and/or sequence-based methods. RESULTS: In the mainland of China, influenza activity recovered in 2021 compared with that in 2020 and intensified during the traditional influenza winter season, but it did not exceed the peak in previous years. Almost all viruses isolated during the study period were of the B/Victoria lineage and were characterized by genetic diversity, with the subgroup 1A.3a.2 viruses currently predominated. 37.8% viruses tested were antigenically similar to reference viruses representing the components of the vaccine for the 2020-2021 and 2021-2022 Northern Hemisphere influenza seasons. In addition, China has a unique subgroup of 1A.3a.1 viruses. All viruses tested were sensitive to neuraminidase inhibitors and endonuclease inhibitors, except two B/Victoria lineage viruses identified to have reduced sensitivity to neuraminidase inhibitors. CONCLUSIONS: Influenza activity increased in the mainland of China in 2021, and caused flu season in the winter of 2021-2022. Although the diversity of influenza (sub)type decreases, B/Victoria lineage viruses show increased genetic and antigenic diversity. The world needs to be fully prepared for the co-epidemic of influenza and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus globally.


Assuntos
COVID-19 , Influenza Humana , Orthomyxoviridae , Antivirais/farmacologia , Antivirais/uso terapêutico , COVID-19/epidemiologia , China/epidemiologia , Humanos , Influenza Humana/epidemiologia , Neuraminidase/genética , Orthomyxoviridae/genética , Pandemias , Filogenia , SARS-CoV-2 , Estações do Ano
6.
Front Pharmacol ; 13: 860492, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35668945

RESUMO

Acute lung injury (ALI) or its aggravated stage acute respiratory distress syndrome (ARDS) is a common severe clinical syndrome in intensive care unit, may lead to a life-threatening form of respiratory failure, resulting in high mortality up to 30-40% in most studies. Nanotechnology-mediated anti-inflammatory therapy is an emerging novel strategy for the treatment of ALI, has been demonstrated with unique advantages in solving the dilemma of ALI drug therapy. Artesunate (ART), a derivative of artemisinin, has been reported to have anti-inflammatory effects. Therefore, in the present study, we designed and synthesized PEGylated ART prodrugs and assessed whether ART prodrugs could attenuate lipopolysaccharide (LPS) induced ALI in vitro and in vivo. All treatment groups were conditioned with ART prodrugs 1 h before challenge with LPS. Significant increased inflammatory cytokines production and decreased GSH levels were observed in the LPS stimulated mouse macrophage cell line RAW264.7. Lung histopathological changes, lung W/D ratio, MPO activity and total neutrophil counts were increased in the LPS-induced murine model of ALI via nasal administration. However, these results can be reversed to some extent by treatment of ART prodrugs. The effectiveness of mPEG2k-SS-ART in inhibition of ALI induced by LPS was confirmed. In conclusion, our results demonstrated that the ART prodrugs could attenuate LPS-induced ALI effectively, and mPEG2k-SS-ART may serve as a novel strategy for treatment of inflammation induced lung injury.

7.
Front Pharmacol ; 13: 902796, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35571137

RESUMO

The small molecule DAPT inhibits the Notch signaling pathway by blocking γ-secretase mediated Notch cleavage. Given the critical role of the Notch signaling axis in inflammation, we asked whether DAPT could block Notch-mediated inflammation and thus exert neuronal protection. We established a mouse model of chronic exposure to cadmium (Cd)-induced toxicity and treated it with DAPT. DAPT was effective in ameliorating Cd-induced multi-organ damage and cognitive impairment in mice, as DAPT restored abnormal performance in the Y-maze, forced swimming and Morris water maze (MWM) tests. DAPT also reversed Cd-induced neuronal loss and glial cell activation to normal as observed by immunofluorescence and immunohistochemistry of brain tissue sections. In addition, Cd-intoxicated mice showed significantly increased levels of the Notch/HES-1 signaling axis and NF-κB, as well as decreased levels of the inflammatory inhibitors C/EBPß and COP1. However, DAPT down regulated the elevated Notch/HES-1 signaling axis to normal, eliminating inflammation and thus protecting the nervous system. Thus, DAPT effectively eliminated the neurotoxicity of Cd, and blocking γ-secretase as well as Notch signaling axis may be a potential target for the development of neuronal protective drugs.

8.
Zhongguo Zhong Yao Za Zhi ; 47(24): 6541-6550, 2022 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-36604902

RESUMO

Cannabidiol is the main non-psychoactive component of Cannabis sativa, which has multiple medicinal activities, such as antiepileptic, immunomodulation, analgesic, antioxidant, anticonvulsant, anti-anxiety and other functions. In recent years, it has been found that cannabidiol can inhibit the proliferation of various tumor cells, induce apoptosis and autophagy of tumor cells, arrest cell cycle, interrupt invasion and metastasis of tumor cells, regulate tumor microenvironment, exert synergistic therapy with other chemotherapeutic drugs, and reduce the toxicity of chemotherapeutic drugs. However, its anti-tumor effect remains controversial and its application is limited. The study of microspheres, nano liposomes and other new drug delivery systems can improve the anti-tumor effect of cannabidiol. In this study, the anti-tumor mechanism and application of cannabidiol were summarized and discussed in order to provide inspirations for its further investigation and application.


Assuntos
Canabidiol , Cannabis , Neoplasias , Humanos , Canabidiol/farmacologia , Canabidiol/uso terapêutico , Neoplasias/tratamento farmacológico , Apoptose , Transtornos de Ansiedade/tratamento farmacológico , Microambiente Tumoral
9.
Inflamm Res ; 70(10-12): 1151-1164, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34661679

RESUMO

OBJECTIVE: Gisenoside Rg1 is a potent neuroprotectant in ginseng. The aim of this study was to investigate the elimination effect of Rg1 on cadmium (Cd)-induced neurotoxicity. MATERIALS AND METHODS: A cumulative Cd exposure mouse model was established. Also, the toxicity of Cd and the protective effect of Rg1 were examined in vitro using cultured neurons and microglia. RESULTS: We found that Cd-intoxicated mice exhibited significant injury in the liver, kidney, small intestine, and testis, along with cognitive impairment. Antioxidant enzymes such as SOD, GSH-Px and CAT were reduced in the blood and brain, and correspondingly, the lipid peroxidation product MDA was elevated. In the brain, astrocytes and microglia were activated, characterized by an increase in inflammatory factors such as TNF-α, IL-1ß and IL-6, as well as their protein markers GFAP and IBA1. However, Rg1 eliminated Cd-induced toxicity and restored oxidative stress and inflammatory responses, correspondingly restoring the behavioral performance of the animals. Meanwhile, the BDNF-TrkB/Akt and Notch/HES-1 signaling axes were involved in the Rg1-mediated elimination of Cd-induced toxicity. CONCLUSION: Rg1 is a promising agent for the elimination of Cd-induced toxicity.


Assuntos
Anti-Inflamatórios/uso terapêutico , Cádmio , Ginsenosídeos/uso terapêutico , Fármacos Neuroprotetores/uso terapêutico , Síndromes Neurotóxicas/tratamento farmacológico , Animais , Anti-Inflamatórios/farmacologia , Apoptose/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Encéfalo/imunologia , Encéfalo/patologia , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Citocinas/genética , Citocinas/imunologia , Ginsenosídeos/farmacologia , Intestino Delgado/efeitos dos fármacos , Intestino Delgado/patologia , Rim/efeitos dos fármacos , Rim/patologia , Fígado/efeitos dos fármacos , Fígado/patologia , Masculino , Camundongos Endogâmicos C57BL , Microglia/efeitos dos fármacos , Microglia/patologia , Neurônios/efeitos dos fármacos , Neurônios/patologia , Fármacos Neuroprotetores/farmacologia , Síndromes Neurotóxicas/imunologia , Síndromes Neurotóxicas/patologia , Estresse Oxidativo/efeitos dos fármacos , Oxirredutases/imunologia , Testículo/efeitos dos fármacos , Testículo/patologia
10.
mBio ; 12(4): e0110021, 2021 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-34225495

RESUMO

Most bacteria employ a two-step indirect tRNA aminoacylation pathway for the synthesis of aminoacylated tRNAGln and tRNAAsn. The heterotrimeric enzyme GatCAB performs a critical amidotransferase reaction in the second step of this pathway. We have previously demonstrated in mycobacteria that this two-step pathway is error prone and translational errors contribute to adaptive phenotypes such as antibiotic tolerance. Furthermore, we identified clinical isolates of the globally important pathogen Mycobacterium tuberculosis with partial loss-of-function mutations in gatA, and demonstrated that these mutations result in high, specific rates of translational error and increased rifampin tolerance. However, the mechanisms by which these clinically derived mutations in gatA impact GatCAB function were unknown. Here, we describe biochemical and biophysical characterization of M. tuberculosis GatCAB, containing either wild-type gatA or one of two gatA mutants from clinical strains. We show that these mutations have minimal impact on enzymatic activity of GatCAB; however, they result in destabilization of the GatCAB complex as well as that of the ternary asparaginyl-transamidosome. Stabilizing complex formation with the solute trehalose increases specific translational fidelity of not only the mutant strains but also of wild-type mycobacteria. Therefore, our data suggest that alteration of GatCAB stability may be a mechanism for modulation of translational fidelity. IMPORTANCE Most bacteria use a two-step indirect pathway to aminoacylate tRNAGln and tRNAAsn, despite the fact that the indirect pathway consumes more energy and is error prone. We have previously shown that the higher protein synthesis errors from this indirect pathway in mycobacteria allow adaptation to hostile environments such as antibiotic treatment through generation of novel alternate proteins not coded by the genome. However, the precise mechanisms of how translational fidelity is tuned were not known. Here, we biochemically and biophysically characterize the critical enzyme of the Mycobacterium tuberculosis indirect pathway, GatCAB, as well as two mutant enzymes previously identified from clinical isolates that were associated with increased mistranslation. We show that the mutants dysregulate the pathway via destabilizing the enzyme complex. Importantly, increasing stability improves translational fidelity in both wild-type and mutant bacteria, demonstrating a mechanism by which mycobacteria may tune mistranslation rates.


Assuntos
Regulação Bacteriana da Expressão Gênica , Mutação , Mycobacterium smegmatis/enzimologia , Mycobacterium smegmatis/genética , Transferases de Grupos Nitrogenados/genética , Biossíntese de Proteínas/genética , Humanos , RNA de Transferência de Glutamina/metabolismo , Aminoacilação de RNA de Transferência , Tuberculose/microbiologia
11.
Cell Biol Int ; 45(6): 1316-1326, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33620117

RESUMO

Hyperglycemia can drive advanced glycation end product (AGE) accumulation and associated nucleus pulposus cell (NPC) dysfunction, but the basis for this activity has not been elucidated. Hypoxia-inducible factor-1α (HIF-1α) is subject to cell-type-specific AGE-mediated regulation. In the current study, we assessed the mechanistic relationship between AGE accumulation and HIF-1α degradation in NPCs. Immunohistochemical staining of degenerated nucleus pulposus (NP) samples was used to assess AGE levels. AGE impact on NPC survival and glycolysis-related gene expression was assessed via 3-(4,5)-dimethylthiazol(-z-y1)-3,5-di-phenyltetrazolium bromide assay and quantitative reverse-transcription polymerase chain reaction (qRT-PCR), while HIF-1α expression in NPCs following AGE treatment was monitored via Western blot analysis and qRT-PCR. Additionally, a luciferase reporter assay was used to monitor HIF-1α transcriptional activity. The importance of the receptor for activated C-kinase 1 (RACK1) as a mediator of HIF-1α degradation was evaluated through gain- and loss-of-function experiments. Competitive binding of RACK1 and HSP90 to HIF-1α was evaluated via immunoprecipitation. Increased AGE accumulation was evident in NP samples from diabetic patients, and AGE treatment resulted in reduced HIF-1α protein levels in NPCs that coincided with reduced HIF-1α transcriptional activity. AGE treatment impaired the stability of HIF-1α, leading to its RACK1-mediated proteasomal degradation in a manner independent of the canonical PHD-mediated degradation pathway. Additionally, RACK1 competed with HSP90 for HIF-1α binding following AGE treatment. AGE treatment of NPCs leads to HIF-1α protein degradation. RACK1 competes with HSP90 for HIF-1α binding following AGE treatment, resulting in posttranslational HIF-1α degradation. These results suggest that AGE is an intervertebral disc degeneration risk factor, and highlight potential avenues for the treatment or prevention of this disease.


Assuntos
Produtos Finais de Glicação Avançada/metabolismo , Proteínas de Choque Térmico HSP90/metabolismo , Hiperglicemia/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Proteínas de Neoplasias/fisiologia , Núcleo Pulposo , Receptores de Quinase C Ativada/fisiologia , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Núcleo Pulposo/metabolismo , Núcleo Pulposo/patologia , Ligação Proteica
12.
J Pharmacol Exp Ther ; 367(2): 292-301, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30171039

RESUMO

The N-methyl-d-aspartate receptor coagonist d-serine is a substrate for the neutral amino acid transporters ASCT1 and ASCT2, which may regulate its extracellular levels in the central nervous system (CNS). We tested inhibitors of ASCT1 and ASCT2 for their effects in rodent models of schizophrenia and visual dysfunction, which had previously been shown to be responsive to d-serine. L-4-fluorophenylglycine (L-4FPG), L-4-hydroxyPG (L-4OHPG), and L-4-chloroPG (L-4ClPG) all showed high plasma bioavailability when administered systemically to rats and mice. L-4FPG showed good brain penetration with brain/plasma ratios of 0.7-1.4; however, values for L-4OHPG and L-4ClPG were lower. Systemically administered L-4FPG potently reduced amphetamine-induced hyperlocomotion in mice, whereas L-4OHPG was 100-fold less effective and L-4ClPG inactive at the doses tested. L-4FPG and L-4OHPG did not impair visual acuity in naive rats, and acute systemic administration of L-4FPG significantly improved the deficit in contrast sensitivity in blue light-treated rats caused by retinal degeneration. The ability of L-4FPG to penetrate the brain makes this compound a useful tool to further evaluate the function of ASCT1 and ASCT2 transporters in the CNS.


Assuntos
Sistema ASC de Transporte de Aminoácidos/antagonistas & inibidores , Esquizofrenia/metabolismo , Transtornos da Visão/metabolismo , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Glicina/farmacologia , Locomoção/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Antígenos de Histocompatibilidade Menor , Ratos , Ratos Long-Evans , Ratos Sprague-Dawley , Receptores de N-Metil-D-Aspartato/antagonistas & inibidores , Esquizofrenia/tratamento farmacológico , Serina/farmacologia , Transtornos da Visão/tratamento farmacológico
13.
Zhongguo Zhong Yao Za Zhi ; 43(3): 544-550, 2018 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-29600620

RESUMO

The dynamic changes of active components in stems and leaves of Mentha Haplocalycis Herba(mint) at different harvest periods were investigated, and the optimum harvest time of mint was explored. In this study, hesperidin, diosmin, didymin and buddleoside were selected as flavonoids index components of mint, and the QAMS method was established to measure the contents of these flavonoids in mint. The contents of 4 flavonoid glycosides in the mint stems and leaves from three habitats harvested in different time were studied and evaluated comprehensively using statistical analysis and principal component analysis (PCA). The results showed that the contents of 4 components in the leaves are higher than that in the stems despite of habitats and harvest time, and they all exhibited dynamic changes along with the harvest periods within the same habitat. Three harvest periods in mid April, mid September and late October scored higher in comprehensive evaluation in Jiangsu region, the genuine producing area of Mentha Haplocalycis Herba. Combined with the yield and contents of active compounds, the optimum harvest time of mint in Jiangsu region was mid September and late October, which is basically consistent with the traditional harvesting periods.


Assuntos
Flavonoides/análise , Mentha/química , Estações do Ano , Compostos Fitoquímicos/análise , Extratos Vegetais , Folhas de Planta/química , Caules de Planta/química
14.
Expert Rev Vaccines ; 16(11): 1155-1169, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28870140

RESUMO

BACKGROUND: Viruses from two antigenically distinct influenza B strains have co-circulated since the mid-1980s, yet inactivated trivalent influenza vaccines (TIVs) with either the Victoria or Yamagata lineage could only provide limited protection from influenza B strain. Quadrivalent influenza vaccine (QIV) including both influenza B lineages can improve protection against circulating influenza B viruses. METHODS: Participants >/ = 3 years of age were recruited, stratified by age, and then randomly allocated at a ratio of 2:1:1 to receive one-injection of the experimental QIV, TIV-Victoria (Vic) or TIV-Yamagata (Yam). The primary objective of this study was to demonstrate that the hemagglutination-inhibition (HI) antibodies induced by the QIV candidate are not inferior to the licensed TIVs. RESULTS: First, 3661 participants received the inoculation. The QIV was found to be non-inferior to TIVs in terms of the geometric mean titers (GMTs) and seroconversion rates (SCRs) of the HI antibodies against shared strains 28 days after completion of inoculation, and was superior to the TIVs against the alternate B strain, which is absent from the TIVs. The occurrences of adverse events (AEs) post-vaccination were similar across the treatment groups. CONCLUSION: The experimental QIV showed good immunogenicity and an acceptable safety profile.


Assuntos
Vacinas contra Influenza/efeitos adversos , Vacinas contra Influenza/imunologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Antivirais/sangue , Criança , Pré-Escolar , China , Método Duplo-Cego , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Feminino , Testes de Inibição da Hemaglutinação , Humanos , Vacinas contra Influenza/administração & dosagem , Masculino , Pessoa de Meia-Idade , Soroconversão , Vacinas de Produtos Inativados/administração & dosagem , Vacinas de Produtos Inativados/efeitos adversos , Vacinas de Produtos Inativados/imunologia , Adulto Jovem
15.
Neuropharmacology ; 126: 70-83, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28807674

RESUMO

The N-methyl-d-aspartate receptor (NMDA) co-agonist d-serine is a substrate for the neutral amino acid transporters ASCT1 (SLC1A4) and ASCT2 (SLC1A5). We identified l-phenylglycine (PG) and its analogs as inhibitors of ASCT1 and ASCT2. PG analogs were shown to be non-substrate inhibitors of ASCT1 and ASCT2 with a range of activities relative to other amino acid transport systems, including sodium-dependent glutamate transporters, the sodium-independent d-serine transporter asc-1 and system L. L-4-chloroPG was the most potent and selective ASCT1/2 inhibitor identified. The PG analogs facilitated theta-burst induced long-term potentiation in rat visual cortex slices in a manner that was dependent on extracellular d-serine. For structurally-related PG analogs, there was an excellent correlation between ASCT1/2 transport inhibition and enhancement of LTP which was not the case for inhibition of asc-1 or system L. The ability of PG analogs to enhance LTP is likely due to inhibition of d-serine transport by ASCT1/2, leading to elevated extracellular levels of d-serine and increased NMDA receptor activity. These results suggest that ASCT1/2 may play an important role in regulating extracellular d-serine and NMDA receptor-mediated physiological effects and that ASCT1/2 inhibitors have the potential for therapeutic benefit.


Assuntos
Sistema ASC de Transporte de Aminoácidos/antagonistas & inibidores , Glicina/análogos & derivados , Potenciação de Longa Duração/efeitos dos fármacos , Córtex Visual/efeitos dos fármacos , Animais , Astrócitos/efeitos dos fármacos , Astrócitos/metabolismo , Proteínas de Transporte de Glutamato da Membrana Plasmática/metabolismo , Glicina/farmacologia , Células HEK293 , Humanos , Antígenos de Histocompatibilidade Menor , Ratos Wistar , Receptores de N-Metil-D-Aspartato , Córtex Visual/fisiologia
16.
Vision Res ; 127: 35-48, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27461280

RESUMO

The NMDA subtype of glutamate receptor and its co-agonist d-serine play a key role in synaptic function in the central nervous system (CNS), including visual cortex and retina. In retinal diseases such as glaucoma and macular degeneration, a loss of vision arises from malfunction of retinal cells, resulting in a glutamate hypofunctional state along the visual pathway in the affected parts of the visual field. An effective strategy to remedy this loss of function might be to increase extracellular levels of d-serine and thereby boost synaptic NMDA receptor-mediated visual transmission and/or plasticity to compensate for the impairment. We tested this idea in brain slices of visual cortex exhibiting long-term potentiation, and in rodent models of visual dysfunction caused by retinal insults at a time when the injury had stabilized to look for neuroenhancement effects. An essential aspect of the in vivo studies involved adapting sweep VEP technology to conscious rats and rabbits and combining it with intracortical recording while the animals were actively attending to visual information. Using this technology allowed us to establish complete contrast sensitivity function curves. We found that systemic d-serine dose-dependently rescued the contrast sensitivity impairment in rats with blue light-induced visual dysfunction. In rabbits with inner retinal dysfunction, both systemic and intravitreal routes of d-serine provided a rescue of visual function. In sum, we show that co-agonist stimulation of the NMDA receptor via administration of exogenous d-serine might be an effective therapeutic strategy to enhance visual performance and compensate for the loss of vision resulting from retinal disease.


Assuntos
Sensibilidades de Contraste/efeitos dos fármacos , Potenciais Evocados Visuais/efeitos dos fármacos , Doenças Retinianas/tratamento farmacológico , Serina/farmacologia , Córtex Visual/efeitos dos fármacos , Animais , Sensibilidades de Contraste/fisiologia , Modelos Animais de Doenças , Masculino , Coelhos , Ratos , Ratos Sprague-Dawley , Doenças Retinianas/fisiopatologia , Córtex Visual/fisiologia
17.
PLoS One ; 11(6): e0156551, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27272177

RESUMO

N-methyl-D-aspartate (NMDA) receptors play critical roles in synaptic transmission and plasticity. Activation of NMDA receptors by synaptically released L-glutamate also requires occupancy of co-agonist binding sites in the tetrameric receptor by either glycine or D-serine. Although D-serine appears to be the predominant co-agonist at synaptic NMDA receptors, the transport mechanisms involved in D-serine homeostasis in brain are poorly understood. In this work we show that the SLC1 amino acid transporter family members SLC1A4 (ASCT1) and SLC1A5 (ASCT2) mediate homo- and hetero-exchange of D-serine with physiologically relevant kinetic parameters. In addition, the selectivity profile of D-serine uptake in cultured rat hippocampal astrocytes is consistent with uptake mediated by both ASCT1 and ASCT2. Together these data suggest that SLC1A4 (ASCT1) may represent an important route of Na-dependent D-serine flux in the brain that has the ability to regulate extracellular D-serine and thereby NMDA receptor activity.


Assuntos
Sistema ASC de Transporte de Aminoácidos/metabolismo , Astrócitos/metabolismo , Hipocampo/metabolismo , Antígenos de Histocompatibilidade Menor/metabolismo , Serina/metabolismo , Animais , Transporte Biológico Ativo/fisiologia , Técnicas de Cultura de Células , Células Cultivadas , Ratos , Ratos Wistar , Receptores de N-Metil-D-Aspartato/metabolismo
18.
Exp Clin Transplant ; 13(1): 62-7, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25343488

RESUMO

OBJECTIVES: We sought to identify the risk factors associated with the early mortality after a living-donor liver transplant. MATERIALS AND METHODS: Two hundred eighteen patients were recruited in this study. Potential risk factors were analyzed using univariate and multivariate analyses. A C statistic equivalent to the area under the receiver operating characteristic curve was used to assess the ability of the model to predict mortality risk during the first 3 months after a living-donor liver transplant. RESULTS: Twenty-six recipients died within the first 3 months after a living-donor liver transplant. On a multivariate analysis, intraoperative allogeneic red blood cell transfusion and the preoperative creatinine levels were independently associated with early postoperative mortality. A prognostic model was proposed in this study (early mortality risk score = 0.107 × intraoperative allogeneic red blood cells transfusion [U] + 0.005 × preoperative creatinine concentration [µmol/L]). Three-month survival rates of patients with high and low scores were 69.8% and 95.5% (P < .001). CONCLUSIONS: Transfusion of intraoperative allogeneic red blood cell and preoperative creatinine levels are associated with the early mortality after living-donor liver transplant. A model to predict early mortality after a living-donor liver transplant based on these risk factors was proposed in this study.


Assuntos
Técnicas de Apoio para a Decisão , Transplante de Fígado/mortalidade , Doadores Vivos , Adulto , Área Sob a Curva , Biomarcadores/sangue , China , Creatinina/sangue , Transfusão de Eritrócitos/efeitos adversos , Transfusão de Eritrócitos/mortalidade , Feminino , Humanos , Estimativa de Kaplan-Meier , Transplante de Fígado/efeitos adversos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Valor Preditivo dos Testes , Modelos de Riscos Proporcionais , Curva ROC , Medição de Risco , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento
19.
Int J Clin Exp Med ; 6(7): 532-9, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23936591

RESUMO

Advanced chronic kidney disease (CKD) is associated with impaired exercise capacity, skeletal muscle dysfunction, and oxidative stress. Mitochondria are the primary source for energy production and generation of reactive oxygen species (ROS). Mitochondrial state 3 respiration, mitochondrial complex I enzyme activity, and tissue porin/actin ratio were determined in the gastrocnemius muscle of male SD rats 14 weeks after 5/6 nephrectomy (CKD) or sham-operation (control). The CKD group exhibited azotemia, hypertension, significant reduction (-39%) of state 3 mitochondrial respiration, and a significant increase in the mitochondrial complex I enzyme activity. The latter is the first step in oxidative phosphorylation, a process linked to production of ROS. These abnormalities were associated with a significant reduction in muscle porin/ß actin ratio denoting substantial reduction of mitochondrial mass in skeletal muscle of animals with CKD. CKD results in impaired mitochondrial respiration, reduced muscle mitochondrial mass, depressed energy production and increased ROS generation in the skeletal muscle. These events can simultaneously contribute to the reduction of exercise capacity and oxidative stress in CKD.

20.
PLoS One ; 8(8): e72235, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23991069

RESUMO

AIM: The selection criteria for patients with hepatocellular carcinoma (HCC) to undergo liver transplantation should accurately predict posttransplant recurrence while not denying potential beneficiaries. In the present study, we attempted to identify risk factors associated with posttransplant recurrence and to expand the selection criteria. PATIENTS AND METHODS: Adult patients with HCC who underwent liver transplantation between November 2004 and September 2012 at our centre were recruited into the current study (N = 241). Clinical and pathological data were retrospectively reviewed. Patients who died during the perioperative period or died of non-recurrence causes were excluded from this study (N = 25). All potential risk factors were analysed using uni- and multi-variate analyses. RESULTS: Sixty-one recipients of 216 qualified patients suffered from recurrence. Similar recurrence-free and long-term survival rates were observed between living donor liver transplant recipients (N = 60) and deceased donor liver transplant recipients (N = 156). Total tumour volume (TTV) and preoperative percentage of lymphocytes (L%) were two independent risk factors in the multivariate analysis. We propose a prognostic score model based on these two risk factors. Patients within our criteria achieved a similar recurrence-free survival to patients within the Milan criteria. Seventy-one patients who were beyond the Milan criteria but within our criteria also had comparable survival to patients within the Milan criteria. CONCLUSIONS: TTV and L% are two risk factors that contribute to posttransplant recurrence. Selection criteria based on these two factors, which are proposed by our study, expanded the Milan criteria without increasing the risk of posttransplant recurrence.


Assuntos
Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Transplante de Fígado , Recidiva Local de Neoplasia , Seleção de Pacientes , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Taxa de Sobrevida , Doadores de Tecidos
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