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1.
Eur J Epidemiol ; 39(5): 549-564, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38625480

RESUMO

There is an unmet need for robust and clinically validated biomarkers of kidney allograft rejection. Here we present the KTD-Innov study (ClinicalTrials.gov, NCT03582436), an unselected deeply phenotyped cohort of kidney transplant recipients with a holistic approach to validate the clinical utility of precision diagnostic biomarkers. In 2018-2019, we prospectively enrolled consecutive adult patients who received a kidney allograft at seven French centers and followed them for a year. We performed multimodal phenotyping at follow-up visits, by collecting clinical, biological, immunological, and histological parameters, and analyzing a panel of 147 blood, urinary and kidney tissue biomarkers. The primary outcome was allograft rejection, assessed at each visit according to the international Banff 2019 classification. We evaluated the representativeness of participants by comparing them with patients from French, European, and American transplant programs transplanted during the same period. A total of 733 kidney transplant recipients (64.1% male and 35.9% female) were included during the study. The median follow-up after transplantation was 12.3 months (interquartile range, 11.9-13.1 months). The cumulative incidence of rejection was 9.7% at one year post-transplant. We developed a distributed and secured data repository in compliance with the general data protection regulation. We established a multimodal biomarker biobank of 16,736 samples, including 9331 blood, 4425 urinary and 2980 kidney tissue samples, managed and secured in a collaborative network involving 7 clinical centers, 4 analytical platforms and 2 industrial partners. Patients' characteristics, immune profiles and treatments closely resembled those of 41,238 French, European and American kidney transplant recipients. The KTD-Innov study is a unique holistic and multidimensional biomarker validation cohort of kidney transplant recipients representative of the real-world transplant population. Future findings from this cohort are likely to be robust and generalizable.


Assuntos
Biomarcadores , Rejeição de Enxerto , Transplante de Rim , Humanos , Transplante de Rim/efeitos adversos , Biomarcadores/urina , Biomarcadores/sangue , Feminino , Masculino , Estudos Prospectivos , Pessoa de Meia-Idade , Adulto , França/epidemiologia , Estudos de Coortes , Transplantados/estatística & dados numéricos
2.
Med Sci Monit ; 30: e941406, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38163948

RESUMO

BACKGROUND Seasonal influenza poses a significant global health concern. Despite the proven effectiveness of the influenza vaccine, its uptake remains low in Vietnam. This study aimed to assess the knowledge, attitudes, and practices of medical students and healthcare workers on influenza vaccine uptake in northern Vietnam. MATERIAL AND METHODS A cross-sectional survey was conducted among 585 participants from northern Vietnam institutions through an anonymous online survey via Google form from June to August 2022. The cut-off for a high level of knowledge and a positive attitude was set at 70% for each variable. Bivariate analysis was conducted to establish associations. Multiple binary logistic regression models were used to identify factors associated with knowledge, attitude, and practice. RESULTS Among the participants, 463 (79.15%) were women, 354 (60.51%) were below 25 years old, 426 (72.82%) were of "Kinh" ethnicity, and 454 (77.61%) were single. Only 237 (40.51%) were vaccinated. Good knowledge and attitude were reported by 36.58% and 42.39% of the participants, respectively. Having a high level of knowledge was found positively associated with having a positive attitude (odds ratio 2.11 [1.48-3.01]). Kinh ethnicity was positively associated with knowledge (1.67 [1.12-2.49]) and attitude (1.97 [1.32-2.94]). Female participants displayed a more positive attitude (2.08 [1.33-3.25]). Several factors influenced the uptake, such as being single (2.07 [1.19-3.59]), being a medical doctor (2.34 [1.09-5.06]), and being advised by a healthcare provider (2.96 [2.00-4.37]). CONCLUSIONS A noticeable gap in knowledge and attitude related to influenza vaccine uptake was found among the target population. Tailored interventions are necessary to improve vaccination coverage.


Assuntos
Vacinas contra Influenza , Influenza Humana , Estudantes de Medicina , Humanos , Feminino , Adulto , Masculino , Estudos Transversais , Vietnã , Conhecimentos, Atitudes e Prática em Saúde , Influenza Humana/prevenção & controle , Influenza Humana/epidemiologia , Pessoal de Saúde , Atitude do Pessoal de Saúde , Inquéritos e Questionários , Vacinação
3.
Chem Biodivers ; 21(5): e202400302, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38454878

RESUMO

This study isolated pure compounds from Canna edulis aerial parts and assessed their antiplatelet and anticoagulant potential. Structural elucidation resulted in the identification of two new compounds: caneduloside A (1) and caneduloside B (2), and eleven known compounds: 6'-acetyl-3,6,2'-tri-p-coumaroyl sucrose (3), 6'-acetyl-3,6,2'-triferuloyl sucrose (4), tiliroside (5), afzelin (6), quercitrin (7), 2-hydroxycinnamaldehyde (8), cinnamic acid (9), 3,4-dimethoxycinnamic acid (10), dehydrovomifoliol (11), 4-hydroxy-3,5-dimethoxybenzaldehyde (12), and (S)-(-)-rosmarinic acid (13). Compounds 3, 4, 6-9, 13 were previously reported for antithrombotic properties. Hence, antithrombotic tests were conducted for 1, 2, 5, 10-12. All tested compounds demonstrated a dose-dependent antiaggregatory effect, and 10 and 12 were the most potent for both ADP and collagen activators. Additionally, 10 and 12 showed anticoagulant effects, with prolonged prothrombin time and activated partial thromboplastin time. The new compound 1 displayed antiplatelet and anticoagulant activity, while 2 mildly inhibited platelet aggregation. C. edulis is a potential source for developing antithrombotic agents.


Assuntos
Anticoagulantes , Componentes Aéreos da Planta , Inibidores da Agregação Plaquetária , Sacarose , Anticoagulantes/farmacologia , Anticoagulantes/química , Anticoagulantes/isolamento & purificação , Inibidores da Agregação Plaquetária/farmacologia , Inibidores da Agregação Plaquetária/química , Inibidores da Agregação Plaquetária/isolamento & purificação , Sacarose/química , Sacarose/farmacologia , Sacarose/metabolismo , Componentes Aéreos da Planta/química , Componentes Aéreos da Planta/metabolismo , Humanos , Ésteres/química , Ésteres/farmacologia , Ésteres/isolamento & purificação , Agregação Plaquetária/efeitos dos fármacos , Myristicaceae/química , Relação Dose-Resposta a Droga , Estrutura Molecular , Relação Estrutura-Atividade , Animais
4.
Kidney Int ; 103(6): 1167-1179, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36990211

RESUMO

We previously established a six-gene-based blood score associated with operational tolerance in kidney transplantation which was decreased in patients developing anti-HLA donor-specific antibodies (DSA). Herein, we aimed to confirm that this score is associated with immunological events and risk of rejection. We measured this using quantitative PCR (qPCR) and NanoString methods from an independent multicenter cohort of 588 kidney transplant recipients with paired blood samples and biopsies at one year after transplantation validating its association with pre-existing and de novo DSA. From 441 patients with protocol biopsy, there was a significant decrease of the score of tolerance in 45 patients with biopsy-proven subclinical rejection (SCR), a major threat associated with pejorative allograft outcomes that prompted an SCR score refinement. This refinement used only two genes, AKR1C3 and TCL1A, and four clinical parameters (previous experience of rejection, previous transplantation, sex of recipient and tacrolimus uptake). This refined SCR score was able to identify patients unlikely to develop SCR with a C-statistic of 0.864 and a negative predictive value of 98.3%. The SCR score was validated in an external laboratory, with two methods (qPCR and NanoString), and on 447 patients from an independent and multicenter cohort. Moreover, this score allowed reclassifying patients with discrepancies between the DSA presence and the histological diagnosis of antibody mediated rejection unlike kidney function. Thus, our refined SCR score could improve detection of SCR for closer and noninvasive monitoring, allowing early treatment of SCR lesions notably for patients DSA-positive and during lowering of immunosuppressive treatment.


Assuntos
Transplante de Rim , Humanos , Transplante de Rim/efeitos adversos , Imunossupressores/uso terapêutico , Anticorpos , Tacrolimo/uso terapêutico , Soro Antilinfocitário , Expressão Gênica , Rejeição de Enxerto/diagnóstico , Rejeição de Enxerto/genética , Rejeição de Enxerto/prevenção & controle , Antígenos HLA/genética , Isoanticorpos , Estudos Retrospectivos
5.
BMC Nephrol ; 24(1): 131, 2023 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-37158838

RESUMO

BACKGROUND: Tacrolimus trough levels (C0) are used in most transplant centres for therapeutic drug monitoring (TDM) of tacrolimus (Tac). The target range of Tac C0 has been remarkably changed, with a target as low as 3-7 ng/ml in the 2009 European consensus conference and a target of 4-12 ng/ml (preferably to 7-12 ng/ml) following the second consensus report in 2019. Our aim was to investigate whether reaching early Tac therapeutic targets and maintaining time in the therapeutic range (TTR) according to the new recommendations may be necessary for preventing acute rejection (AR) during the first month after transplantation. METHODS: A retrospective study including 160 adult renal transplant patients (113 men and 47 women) with a median age of 36.3 (20-44) years was conducted between January 2018 and December 2019 at 103 Military Hospital (Vietnam). Tac trough levels were recorded in the first month, and episodes of AR were confirmed by kidney biopsy. Tac TTR was calculated as the percentage of time within the target range of 7-12 ng/ml, according to the 2019 second consensus report. Multivariate Cox analysis was performed to identify the correlation between the Tac target range and TTR with AR. RESULTS: In the first month after RT, 14 (8.8%) patients experienced AR. There was a significant difference in the incidence of AR between the Tac level groups of < 4, 4-7 and > 7 ng/ml (p = 0.0096). In the multivariate Cox analysis, after adjusting for related factors, a mean Tac level > 7 ng/ml was associated with an 86% decreased risk of AR compared with that of 4-7 ng/ml in the first month (HR, 0.14; 95% CI, 0.03-0.66; p = 0.0131). Every 10% increase in TTR was associated with a 28% lower risk of AR (HR, 0.72; 95% CI, 0.55-0.94; p = 0.014). CONCLUSION: Gaining and maintaining Tac C0 according to the 2019 second consensus report might reduce the risk of AR in the first month following transplantation.


Assuntos
Transplante de Rim , Tacrolimo , Adulto , Feminino , Humanos , Masculino , Consenso , Transplante de Rim/efeitos adversos , Análise Multivariada , Estudos Retrospectivos , Tacrolimo/uso terapêutico
6.
Int J Mol Sci ; 24(15)2023 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-37569890

RESUMO

Fallopia japonica (Asian knotweed) is a medicinal herb traditionally used to treat inflammation, among other conditions. However, the effects of F. japonica root extract (FJE) on airway inflammation associated with combined allergic rhinitis and asthma (CARAS) and the related mechanisms have not been investigated. This study examined the effect of FJE against CARAS in an ovalbumin (OVA)-induced CARAS mouse model. Six-week-old male BALB/c mice were randomly segregated into six groups. Mice were sensitized intraperitoneally with OVA on days 1, 8, and 15, and administered saline, Dexamethasone (1.5 mg/kg), or FJE (50, 100, or 200 mg/kg) once a day for 16 days. Nasal symptoms, inflammatory cells, OVA-specific immunoglobulins, cytokine production, mast cell activation, and nasal histopathology were assessed. Administration of FJE down-regulated OVA-specific IgE and up-regulated OVA-specific IgG2a in serum. FJE reduced the production of T helper (Th) type 2 cytokines, and the Th1 cytokine levels were enhanced in nasal and bronchoalveolar lavage fluid. Moreover, FJE positively regulated allergic responses by reducing the accumulation of inflammatory cells, improving nasal and lung histopathological characteristics, and inhibiting inflammation-associated cytokines. FJE positively modulated the IL-33/TSLP/NF-B signaling pathway, which is involved in regulating inflammatory cells, immunoglobulin levels, and pro-inflammatory cytokines at the molecular level.


Assuntos
Asma , Fallopia japonica , Rinite Alérgica , Animais , Masculino , Camundongos , Asma/induzido quimicamente , Asma/tratamento farmacológico , Asma/metabolismo , Líquido da Lavagem Broncoalveolar , Citocinas/metabolismo , Modelos Animais de Doenças , Fallopia japonica/química , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Interleucina-33/farmacologia , Camundongos Endogâmicos BALB C , NF-kappa B/metabolismo , Ovalbumina , Rinite Alérgica/metabolismo , Transdução de Sinais
7.
J Immunol ; 205(9): 2391-2401, 2020 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-32948686

RESUMO

Granzyme B-expressing B cells have been shown to be an important regulatory B cell subset in humans. However, it is unclear which subpopulations of B cells express GZMB under normal conditions and which protocols effectively induce ex vivo expansion of GZMB+ B cells. We found that in the peripheral blood of normal individuals, plasmablasts were the major B cell subpopulation that expressed GZMB. However, when using an in vitro plasmablast differentiation protocol, we obtained only 2% GZMB+ B cells. Nevertheless, using an expansion mixture containing IL-21, anti-BCR, CpG oligodeoxynucleotide, CD40L, and IL-2, we were able to obtain more than 90% GZMB+ B cells after 3 d culture. GZMB+ B cells obtained through this protocol suppressed the proliferation of autologous and allogenic CD4+CD25- effector T cells. The suppressive effect of GZMB+ B cells was partially GZMB dependent and totally contact dependent but was not associated with an increase in effector T cell apoptosis or uptake of GZMB by effector T cells. Interestingly, we showed that GZMB produced by B cells promoted GZMB+ B cell proliferation in ERK1/2-dependent manner, facilitating GZMB+ B cell expansion. However, GZMB+ B cells tended to undergo apoptosis after prolonged stimulation, which may be considered a negative feedback mechanism to limit their uncontrolled expansion. Finally, we found that expanded GZMB+ B cells exhibited a regulatory phenotype and were enriched in CD307bhi, CD258hiCD72hi, and CD21loPD-1hi B cell subpopulations. Our study, to our knowledge, provides new insight into biology of GZMB+ B cells and an efficient method to expand GZMB+ B cells for future cell therapy applications.


Assuntos
Linfócitos B Reguladores/microbiologia , Granzimas/imunologia , Apoptose/imunologia , Ligante de CD40/imunologia , Diferenciação Celular/imunologia , Proliferação de Células/fisiologia , Células Cultivadas , Humanos , Interleucinas/imunologia , Leucócitos Mononucleares/imunologia
8.
Int J Mol Sci ; 23(23)2022 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-36499702

RESUMO

A new terminology "combined allergic rhinitis and asthma syndrome (CARAS)" was introduced to describe patients suffering from both allergic rhinitis (AR) and asthma. The pathogenesis of allergic airway inflammation has been well known, with the main contribution of TH1/TH2 imbalance and mast cell degranulation. Artemisia gmelinii has been used as an herbal medicine with its hepaprotective, anti-inflammatory, and antioxidant properties. In this study, the effect of A. gmelinii extracts (AGE) on the ovalbumin (OVA)-induced CARAS mouse model was investigated. AGE administration significantly alleviated the nasal rubbing and sneezing, markedly down-regulated both OVA-specific IgE, IgG1, and histamine levels, and up-regulated OVA-specific IgG2a in serum. The altered histology of nasal and lung tissues of CARAS mice was effectively ameliorated by AGE. The AGE treatment group showed markedly increased levels of the TH1 cytokine interleukin (IL)-12 and TH1 transcription factor T-bet. In contrast, the levels of the TH2 cytokines, including IL-4, IL-5, IL-13, and the TH2 transcription factor GATA-3, were notably suppressed by AGE. Moreover, AGE effectively prevented mast cell degranulation in vitro and mast cell infiltration in lung tissues in vivo. Based on these results, we suggest that AGE could be a potential therapeutic agent in OVA-induced CARAS by virtue of its role in balancing the TH1/TH2 homeostasis and inhibiting the mast cell degranulation.


Assuntos
Artemisia , Asma , Rinite Alérgica , Animais , Camundongos , Asma/tratamento farmacológico , Degranulação Celular , Citocinas/farmacologia , Modelos Animais de Doenças , Imunoglobulina G , Inflamação/tratamento farmacológico , Mastócitos , Camundongos Endogâmicos BALB C , Ovalbumina/farmacologia , Extratos Vegetais , Rinite Alérgica/patologia , Células Th2 , Fatores de Transcrição , Células Th1
9.
Environ Sci Policy ; 136: 497-509, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35855780

RESUMO

This paper uses Vietnam - where overexploitation of wildlife resources is a major threat to biodiversity conservation - as a case study to examine how government officials perceive the impacts of COVID-19 on wildlife farming, as well as the opportunities and challenges presented for sustainable wildlife management. Findings show Vietnamese government officials perceive COVID-19 to have had mixed impacts on wildlife conservation policies and practice. While the pandemic strengthened the legal framework on wildlife conservation, implementation and outcomes have been poor, as existing policies are unclear, contradictory, and poorly enforced. Our paper also shows policymakers in Vietnam are not in favor of banning wildlife trade. As our paper documents the immediate impacts of the pandemic on wildlife farming, more research is necessary to analyse longer-term impacts.

10.
Int J Mol Sci ; 22(21)2021 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-34768915

RESUMO

Ursolic acid (UA), a pentacyclic triterpenoid extracted from various plants, inhibits cell growth, metastasis, and tumorigenesis in various cancers. Chemotherapy resistance and the side effects of paclitaxel (PTX), a traditional chemotherapy reagent, have limited the curative effect of PTX in esophageal cancer. In this study, we investigate whether UA promotes the anti-tumor effect of PTX and explore the underlying mechanism of their combined effect in esophageal squamous cell carcinoma (ESCC). Combination treatment with UA and PTX inhibited cell proliferation and cell growth more effectively than either treatment alone by inducing more significant apoptosis, as indicated by increased sub-G1 phase distribution and protein levels of cleaved-PARP and cleaved caspase-9. Similar to the cell growth suppressive effect, the combination of UA and PTX significantly inhibited cell migration by targeting uPA, MMP-9, and E-cadherin in ESCC cells. In addition, combination treatment with UA and PTX significantly activated p-GSK-3ß and suppressed the activation of Akt and FOXM1 in ESCC cells. Those effects were enhanced by the Akt inhibitor LY2940002 and inverted by the Akt agonist SC79. In an in vivo evaluation of a murine xenograft model of esophageal cancer, combination treatment with UA and PTX suppressed tumor growth significantly better than UA or PTX treatment alone. Thus, UA effectively potentiates the anti-tumor efficacy of PTX by targeting the Akt/FOXM1 cascade since combination treatment shows significantly more anti-tumor potential than PTX alone both in vitro and in vivo. Combination treatment with UA and PTX could be a new strategy for curing esophageal cancer patients.


Assuntos
Antineoplásicos/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Neoplasias Esofágicas/tratamento farmacológico , Carcinoma de Células Escamosas do Esôfago/tratamento farmacológico , Paclitaxel/farmacologia , Triterpenos/farmacologia , Animais , Apoptose/efeitos dos fármacos , Caderinas/metabolismo , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sinergismo Farmacológico , Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas do Esôfago/imunologia , Proteína Forkhead Box M1/metabolismo , Glicogênio Sintase Quinase 3 beta/metabolismo , Humanos , Metaloproteinase 9 da Matriz/metabolismo , Camundongos , Invasividade Neoplásica/patologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Ácido Ursólico
11.
Int J Mol Sci ; 22(15)2021 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-34360939

RESUMO

Air pollution-related particulate matter (PM) exposure reportedly enhances allergic airway inflammation. Some studies have shown an association between PM exposure and a risk for allergic rhinitis (AR). However, the effect of PM for AR is not fully understood. An AR mouse model was developed by intranasal administration of 100 µg/mouse PM with a less than or equal to 2.5 µm in aerodynamic diameter (PM2.5) solution, and then by intraperitoneal injection of ovalbumin (OVA) with alum and intranasal challenging with 10 mg/mL OVA. The effects of PM2.5 on oxidative stress and inflammatory response via the Nrf2/NF-κB signaling pathway in mice with or without AR indicating by histological, serum, and protein analyses were examined. PM2.5 administration enhanced allergic inflammatory cell expression in the nasal mucosa through increasing the expression of inflammatory cytokine and reducing the release of Treg cytokine in OVA-induced AR mice, although PM2.5 exposure itself induced neither allergic responses nor damage to nasal and lung tissues. Notably, repeated OVA-immunization markedly impaired the nasal mucosa in the septum region. Moreover, AR with PM2.5 exposure reinforced this impairment in OVA-induced AR mice. Long-term PM2.5 exposure strengthened allergic reactions by inducing the oxidative through malondialdehyde production. The present study also provided evidence, for the first time, that activity of the Nrf2 signaling pathway is inhibited in PM2.5 exposed AR mice. Furthermore, PM2.5 exposure increased the histopathological changes of nasal and lung tissues and related the inflammatory cytokine, and clearly enhanced PM2.5 phagocytosis by alveolar macrophages via activating the NF-κB signaling pathway. These obtained results suggest that AR patients may experience exacerbation of allergic responses in areas with prolonged PM2.5 exposure.


Assuntos
Poluição do Ar/efeitos adversos , Inflamação/imunologia , Estresse Oxidativo/efeitos dos fármacos , Material Particulado/toxicidade , Rinite Alérgica/imunologia , Animais , Citocinas/imunologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Fator 2 Relacionado a NF-E2/imunologia , NF-kappa B/imunologia , Ovalbumina/imunologia
12.
Molecules ; 26(12)2021 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-34205529

RESUMO

Polyscias fruticosa (L.) leaves contain significant bioactive compounds with high antioxidant activity such as chlorophylls, total polyphenols, etc. but these have still been underutilized. In this study, the kinetics of chlorophyll and antioxidant activity extraction from P. fruticosa leaves by microwave-assisted extraction (MAE) were investigated. Microwave power was 300, 450, or 600 (W); the ratio of material/solvent varied from 1:40 to 1:80 (g/mL). In this study, the second-order kinetic model successfully predicted the change of chlorophyll and antioxidant activity during MAE. The increase of microwave power or/and the solvent amount increased saturated extraction efficiency and the extraction rate constant. However, the saturated concentration of chlorophyll and antioxidant activity increased with the increment of microwave power and the decrease in solvent amount.


Assuntos
Antioxidantes/farmacologia , Araliaceae/química , Clorofila/farmacologia , Extratos Vegetais/farmacologia , Folhas de Planta/química , Cromatografia Líquida de Alta Pressão/métodos , Etanol/química , Cinética , Micro-Ondas , Extratos Vegetais/química , Polifenóis/química , Polifenóis/farmacologia , Solventes/química
13.
Molecules ; 26(24)2021 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-34946774

RESUMO

Although avocado is a superfood rich in phytochemicals with high antioxidant activities, studies on the antibacterial properties of its pulp are limited, except for seed and peel portions. In this study, three types of solvent (acetone, methanol, and diethyl ether) were used to obtain the extracts from "Maluma" avocado pulp powder prepared by infrared drying. The extracts were analyzed for total polyphenols, phytopigments (total chlorophylls and carotenoids), antioxidant activities (ferric-reducing antioxidant power (FRAP), 2,2-Diphenyl-1-picrylhydrazyl (DPPH), and 2,2-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid (ABTS) assays), and antibacterial activities against seven pathogens (Shigella sonnei ATCC 9290, Escherichia coli ATCC 8739, Salmonella typhi ATCC 6539, Vibrio parahaemolyticus ATCC 17802, Proteus mirabilis ATCC 25933, Staphylococcus aureus ATCC 6538, and Bacillus cereus ATCC 11778). The results showed that the acetone solvent could extract the highest polyphenols and chlorophylls with the highest antioxidant activity in terms of ABTS and DPPH assays. In contrast, diethyl ether exhibited the most significant content of carotenoids and FRAP values. However, the methanol extract was the best solvent, exerting the strongest antibacterial and meaningful antioxidant activities. For the bacterial activities, Gram-positive pathogens (Bacillus cereus and Staphylococcus aureus) were inhibited more efficiently by avocado extracts than Gram-negative bacteria. Therefore, the extracts from avocado powder showed great potential for applications in food processing and preservation, pharmaceuticals, and cosmetics.


Assuntos
Antibacterianos , Antioxidantes , Bactérias/crescimento & desenvolvimento , Persea/química , Extratos Vegetais , Antibacterianos/química , Antibacterianos/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia
14.
Clin Infect Dis ; 71(12): 3252-3259, 2020 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-32521000

RESUMO

Delamanid, a-first-in-class bicyclic nitroimidazole, was recently approved for multidrug-resistant tuberculosis treatment. Pitted against the hope for improving treatment outcomes is the threat of the rapid resistance emergence. This review provides information on the mechanisms of action, resistance emergence, and drug susceptibility testing (DST) for delamanid. Delamanid resistance has already been reported in both in vitro experiments and clinical settings. Although mutations conferring delamanid resistance have been identified in fbiA, fbiB, fbiC, ddn, and fgd1 genes of Mycobacterium tuberculosis, knowledge about the molecular resistance mechanisms is limited, and there remains no standardized DST method. The rapid acquisition of delamanid resistance emphasizes the need for optimal use of new drugs, the need for drug resistance surveillance, and a comprehensive understanding of drug resistance mechanisms. Further studies are necessary to investigate genetic and phenotypic changes that determine clinically relevant delamanid resistance to help develop a rapid delamanid DST.


Assuntos
Mycobacterium tuberculosis , Nitroimidazóis , Tuberculose Resistente a Múltiplos Medicamentos , Antituberculosos/farmacologia , Antituberculosos/uso terapêutico , Humanos , Testes de Sensibilidade Microbiana , Mycobacterium tuberculosis/genética , Nitroimidazóis/uso terapêutico , Oxazóis/uso terapêutico , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico
15.
Am J Transplant ; 20(1): 101-111, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31344323

RESUMO

IL-7 is an important cytokine for T cell lymphopoiesis. Blockade of the IL-7 signaling pathway has been shown to induce long-term graft survival or graft tolerance in murine transplant models through inhibiting T cell homeostasis and favoring immunoregulation. In this study, we assessed for the first time the effects of a blocking anti-human cluster of differentiation 127 (CD127) mAb administered in combination with low-dose tacrolimus or thymoglobulin in a life-sustaining kidney allograft model in baboons. Contrary to our expectation, the addition of an anti-CD127 mAb to the treatment protocols did not prolong graft survival compared to low-dose tacrolimus alone or thymoglobulin alone. Anti-CD127 mAb administration led to full CD127 receptor occupancy during the follow-up period. However, all treated animals lost their kidney graft between 1 week and 2 weeks after transplantation. Unlike in rodents, in nonhuman primates, anti-CD127 mAb treatment does not decrease the absolute numbers of lymphocyte and lymphocyte subsets and does not effectively inhibit postdepletional T cell proliferation and homeostasis, suggesting that IL-7 is not a limiting factor for T cell homeostasis in primates.


Assuntos
Anticorpos Monoclonais/farmacologia , Rejeição de Enxerto/tratamento farmacológico , Sobrevivência de Enxerto/efeitos dos fármacos , Subunidade alfa de Receptor de Interleucina-7/imunologia , Transplante de Rim/efeitos adversos , Depleção Linfocítica/métodos , Receptores de Interleucina-7/antagonistas & inibidores , Animais , Rejeição de Enxerto/etiologia , Rejeição de Enxerto/patologia , Sobrevivência de Enxerto/imunologia , Papio , Complicações Pós-Operatórias
16.
Clin Exp Allergy ; 50(7): 824-834, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32418317

RESUMO

BACKGROUND: Interleukin-7 (IL-7) is the most important cytokine for T-cell homeostasis. IL-7 signals through the IL-7 receptor (IL-7R) which is composed of an alpha chain (IL-7Rα), also called CD127 and a common gamma chain. T lymphocytes, especially T helper type 2, play a crucial role in the pathobiology of allergic asthma. OBJECTIVE: To study the effects of an anti-CD127 monoclonal antibody (mAb) in a murine model of allergic airway inflammation induced by house dust mite (HDM). METHODS: Allergic airway inflammation was induced in mice using a protocol comprising 4 weekly percutaneous sensitizations followed by 2 weekly intranasal challenges with total HDM extracts and treated by intraperitoneal injections of an anti-CD127 mAb. Because CD127 is shared by both IL-7R and the receptor for thymic stromal lymphopoietin (TSLP), a group of mice was also treated with an anti-IL-7 mAb to block only the IL-7 signalling pathway. RESULTS: Anti-CD127 mAb-treated mice showed significantly lower airway resistance in response to methacholine and improvement in lung histology compared with isotype mAb-treated animals. Anti-CD127 mAb treatment significantly decreased the mRNA expression of Th2 cytokines (IL-4, IL-5, and IL-13) and chemokines (CCL5/RANTES) in lung tissue, decreased the secretion of Th2 cytokines (IL-4, IL-5, and IL-13) and chemokines (CXCL1 and CCL11/eotaxin) in bronchoalveolar lavage fluid (BALF), decreased serum HDM-specific IgE, and reduced the number of total leucocytes and leucocyte subpopulations such as eosinophils, macrophages, lymphocytes, T lymphocytes, and ILC2 in BALF and lung tissue. Mice treated with anti-IL-7 mAb also showed less allergic airway inflammation as evidenced by significantly lower airway resistance and fewer leucocytes in BALF and lung tissue compared to mice treated with the corresponding isotype control mAb. CONCLUSION AND CLINICAL RELEVANCE: Targeting the IL-7Rα by an anti-CD127 mAb improves allergic airway inflammation in mice and presents as a potential therapeutic approach for allergic asthma.


Assuntos
Anticorpos Monoclonais/farmacologia , Asma , Subunidade alfa de Receptor de Interleucina-7 , Transdução de Sinais/efeitos dos fármacos , Células Th2/imunologia , Animais , Anticorpos Monoclonais/imunologia , Asma/tratamento farmacológico , Asma/imunologia , Feminino , Inflamação/tratamento farmacológico , Inflamação/imunologia , Subunidade alfa de Receptor de Interleucina-7/antagonistas & inibidores , Subunidade alfa de Receptor de Interleucina-7/imunologia , Camundongos Endogâmicos BALB C , Pyroglyphidae/imunologia , Transdução de Sinais/imunologia
17.
Cell Immunol ; 351: 104035, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32051090

RESUMO

BACKGROUND: Piper nigrum L. (Piperaceae) is commonly used as a spice and traditional medicine in many countries. It has been reported to have anti-oxidant, anti-bacterial, anti-tumor, anti-mutagenic, anti-diabetic, and anti-inflammatory properties. However, the protective role of P. nigrum on epithelial function of upper respiratory tract injury in an allergic rhinitis (AR) mouse model has been unclear. This study aims to investigate the effects of P. nigrum fruit extract (PNE) on the nasal epithelial barrier function of the upper respiratory tract in an ovalbumin (OVA)-induced AR model. METHODS: AR mouse model was established by intraperitoneal injection with 200 µL saline containing 50 µg OVA adsorbed to 1 mg aluminum hydroxide, and intranasal challenge with 20 µL per nostril of 1 mg/ml OVA. Besides, mice were orally administrated once daily with PNE and dexamethasone (Dex) in 13 days. The nasal symptoms, inflammatory cells, OVA-specific immunoglobulins, cytokines, nasal histopathology, and immunohistochemistry were evaluated. RESULTS: The PNE oral administrations inhibited allergic responses via reduction of OVA-specific antibodies levels and mast cells histamine release, accordingly, the nasal symptoms in the early-phase reaction were also clearly ameliorated. In both nasal lavage fluid and nasal tissue, PNE suppressed the inflammatory cells accumulation, specifically with eosinophils. The intravenous Evans blue injection illustrated the epithelial permeability reduction of nasal mucosa layer in PNE-treated mice. Also; PNE treatments protected the epithelium integrity by preventing the epithelial shedding from nasal mucosa; as a result of enhancing the strong expression of the E-cadherin tight junction protein in cell-to-cell junctions, as well as inhibiting the degraded levels of zonula occludens-1 (ZO-1) and occludin into the nasal cavity. Additionally, PNE protected against nasal epithelial barrier dysfunction via enhancing the expression of Nrf2 activated form which led to increasing synthesis of the anti-inflammation enzyme HO-1. CONCLUSIONS: These obtained results suggest that PNE has a promising strategy for epithelial barrier stabilization in allergic rhinitis treatment.


Assuntos
Heme Oxigenase-1/metabolismo , Proteínas de Membrana/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Mucosa Nasal/efeitos dos fármacos , Extratos Vegetais/farmacologia , Rinite Alérgica/metabolismo , Animais , Anti-Inflamatórios/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Mucosa Nasal/metabolismo , Ovalbumina/toxicidade , Piper nigrum , Rinite Alérgica/induzido quimicamente , Transdução de Sinais/efeitos dos fármacos
18.
FASEB J ; 33(12): 13386-13397, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31550172

RESUMO

Gut-homing γδ T cells are induced by chemokines and cell adhesion molecules and play a critical role in homeostasis and mucosal immunity; however, little is known regarding their upstream regulators. We investigated the role of Axl as a specific regulator of chemokines and cell adhesion molecule in the distribution of intestinal γδ T cells. The population of γδ T-cell receptor-positive cells including Vγ1 and Vγ7 subsets was remarkably increased in the intraepithelial lymphocytes of Axl-/- mice compared with those of wild-type (WT) mice. An increased number of migrated γδ T cells were observed in the coculture with intraepithelial cells from Axl-/- mice. The mRNA expression level of chemokine (C-C motif) ligand (CCL) 25 was specifically higher in the small intestine of Axl-/- mice than in WT mice. In adoptive transfer, the migration of both thymic and extrathymic γδ T cells was increased in Axl-/- mice. The activation of Axl signaling down-regulated CCL25 expression via ERK signaling pathway and reduced the population of γδ T cells. Systemic dissemination was suppressed in Axl-/- mice infected with Salmonella typhimurium. Thus, our findings suggest that Axl plays a critical role in regulating the migration of γδ T cells for the maintenance of homeostasis and bacterial resistance.-Kim, S.-M., Park, M., Yee, S.-M., Ji, K.-Y., Lee, E.-H., Nguyen, T.-V., Nguyen, T. H.-L., Jang, J., Kim, E.-M., Choi, H.-R., Yun, C.-H., Kang, H.-S. Axl is a key regulator of intestinal γδ T-cell homeostasis.


Assuntos
Células Epiteliais/imunologia , Homeostase , Intestino Delgado/imunologia , Proteínas Proto-Oncogênicas/fisiologia , Receptores Proteína Tirosina Quinases/fisiologia , Receptores de Antígenos de Linfócitos T gama-delta/imunologia , Subpopulações de Linfócitos T/imunologia , Febre Tifoide/imunologia , Animais , Movimento Celular , Células Cultivadas , Quimiocinas CC/metabolismo , Células Epiteliais/metabolismo , Células Epiteliais/microbiologia , Imunidade nas Mucosas , Mucosa Intestinal/imunologia , Mucosa Intestinal/metabolismo , Mucosa Intestinal/microbiologia , Intestino Delgado/metabolismo , Intestino Delgado/microbiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptores de Antígenos de Linfócitos T gama-delta/metabolismo , Salmonella typhimurium/fisiologia , Febre Tifoide/metabolismo , Febre Tifoide/microbiologia , Receptor Tirosina Quinase Axl
19.
Int J Mol Sci ; 21(10)2020 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-32408566

RESUMO

Mangiferin (MF), extracted from mango trees, is considered to have anti-inflammatory, anti-apoptotic, and antioxidant effects. However, its effects on allergic rhinitis (AR), remain unclear. We investigated the mechanisms underlying the protective action of MF in ovalbumin (OVA)-induced AR models. AR was induced by OVA challenge in BALB/c mice. Prior to this, MF and dexamethasone were administered. Mice were examined for nasal mucosal inflammation, the generation of allergen-specific cytokine response, and histopathological changes in the nasal mucosa and lung tissue. MF ameliorated nasal symptoms and nasal mucosa inflammation in OVA-induced AR and reduced inflammatory cell infiltration and epithelial disruption in these tissues. MF inhibited the overproduction of Th2/Th17 cytokines and transcription factors. MF downregulated the HO-1/Nrf2 pathways, reduced oxidative stress biomarker levels, and the NF-κB signaling pathways were inhibited. MF exerts protective effects in AR by inhibiting NF-κB and activating HO-1/Nrf2 pathways. MF could be used for the treatment of AR.


Assuntos
Heme Oxigenase-1/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , NF-kappa B/metabolismo , Rinite Alérgica/prevenção & controle , Transdução de Sinais/efeitos dos fármacos , Xantonas/farmacologia , Animais , Citocinas/metabolismo , Inflamação/metabolismo , Inflamação/prevenção & controle , Masculino , Camundongos Endogâmicos BALB C , Mucosa Nasal/efeitos dos fármacos , Mucosa Nasal/metabolismo , Mucosa Nasal/patologia , Ovalbumina , Rinite Alérgica/induzido quimicamente , Rinite Alérgica/metabolismo , Células Th17/efeitos dos fármacos , Células Th17/metabolismo , Células Th2/efeitos dos fármacos , Células Th2/metabolismo
20.
Xenotransplantation ; 26(6): e12535, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31293002

RESUMO

Humans cannot synthesize N-glycolylneuraminic acid (Neu5Gc) but dietary Neu5Gc can be absorbed and deposited on endothelial cells (ECs) and diet-induced anti-Neu5Gc antibodies (Abs) develop early in human life. While the interaction of Neu5Gc and diet-induced anti-Neu5Gc Abs occurs in all normal individuals, endothelium activation by elicited anti-Neu5Gc Abs following a challenge with animal-derived materials, such as following xenotransplantation, had been postulated. Ten primary human EC preparations were cultured with affinity-purified anti-Neu5Gc Abs from human sera obtained before or after exposure to Neu5Gc-glycosylated rabbit IgGs (elicited Abs). RNAs of each EC preparation stimulated in various conditions by purified Abs were exhaustively sequenced. EC transcriptomic patterns induced by elicited anti-Neu5Gc Abs, compared with pre-existing ones, were analyzed. qPCR, cytokines/chemokines release, and apoptosis were tested on some EC preparations. The data showed that anti-Neu5Gc Abs induced 967 differentially expressed (DE) genes. Most DE genes are shared following EC activation by pre-existing or anti-human T-cell globulin (ATG)-elicited anti-Neu5Gc Abs. Compared with pre-existing anti-Neu5Gc Abs, which are normal component of ECs environment, elicited anti-Neu5Gc Abs down-regulated 66 genes, including master genes of EC function. Furthermore, elicited anti-Neu5Gc Abs combined with complement-containing serum down-regulated most transcripts mobilized by serum alone. Both types of anti-Neu5Gc Abs-induced a dose- and complement-dependent release of selected cytokines and chemokines. Altogether, these data show that, compared with pre-existing anti-Neu5Gc Abs, ATG-elicited anti-Neu5Gc Abs specifically modulate genes related to cytokine responses, MAPkinase cascades, chemotaxis, and integrins and do not skew the EC transcriptome toward a pro-inflammatory profile in vitro.


Assuntos
Anticorpos/farmacologia , Células Endoteliais/efeitos dos fármacos , Endotélio/metabolismo , Transcriptoma/genética , Animais , Anticorpos/imunologia , Células Endoteliais/imunologia , Humanos , Imunoglobulina G/metabolismo , Transcriptoma/imunologia , Transplante Heterólogo/métodos
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