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1.
Anal Chim Acta ; 1301: 342448, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38553120

RESUMO

BACKGROUND: The incorporation of bimetallic magnetic ionic liquids (MILs) in microextraction methods is an emerging trend due to the improved magnetic susceptibility offered by these solvents, which relies on the presence of metallic components in both the cation and the anion. This feature favors easy magnetic separation of these solvents in analytical sample preparation strategies. However, reported liquid-phase microextraction methods based on bimetallic MILs still present an important drawback in that the MILs are highly viscous, making a dispersive solvent during the microextraction procedure necessary, while also requiring a tedious back-extraction step prior to the chromatographic analysis. RESULTS: We propose for the first time a new generation of ultra-low viscosity bimetallic MILs composed of two paramagnetic Mn(II) complexes characterized by their easy usage in dispersive liquid-liquid microextraction (DLLME). The approach does not require dispersive solvent and the MIL-DLLME setup was directly combined with high-performance liquid chromatography (HPLC) and fluorescence detection (FD), without any back-extraction step. The approach was evaluated for the determination of five monohydroxylated polycyclic aromatic hydrocarbons, as carcinogenic biomarkers, in human urine. Optimum conditions of the MIL-DLLME method included the use of a low MIL volume (75 µL), a short extraction time (5 min), and no need of any dispersive solvent neither NaCl. The method presented limits of detection down to 7.50 ng L-1, enrichment factors higher than 17, and provided inter-day relative standard deviation lower than 11%. Analysis of urine samples was successfully performed, with biomarker content found at levels between 0.24 and 7.8 ng mL-1. SIGNIFICANCE: This study represents the first liquid-phase microextraction method using the new generation of low-viscous bimetallic MILs. The proposed MIL-DLLME approach represents 2 important advances with respect to previous methods employing bimetallic MILs: 1) no dispersive solvent is required, and 2) direct injection of the MIL in the HPLC is possible after minor dilution (no back extraction steps are required). Therefore, the microextraction strategy is simple, rapid, and consumes very small amounts of energy.

2.
Biomed Pharmacother ; 168: 115750, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37871555

RESUMO

BACKGROUND: Dual therapy (DT) has shown comparable results to triple therapy (TT) in efficacy and other immunological aspects. However, there are still some concerns about DT, including several immunological features. Therefore, we evaluated whether HIV-1-specific memory T-cell responses and exhaustion phenotypes are adversely influenced after simplification to DT. METHODS: HIV-1-specific CD4+ and CD8+ T-cell responses were assessed by intracellular cytokine and degranulation marker staining, and polyfunctionality indexes after stimulation with a Gag peptide pool. Exhaustion phenotypes were evaluated by PD-1, TIM-3, and LAG-3 expression in CD4+ and CD8+ T cells. RESULTS: Forty participants in the TRIDUAL trial (ClinicalTrials.gov: NCT03447873) who were randomized to continue integrase inhibitor-based TT (n = 20) or to switch to DT (dolutegravir or darunavir/cobicistat plus lamivudine) (n = 20). After 96 weeks, the magnitude of CD4+ and CD8+ T-cell responses was similar in both treatment arms (p = 0.221 and p = 0.602, respectively). The CD4+ polyfunctionality index decreased in the TT arm (p = 0.013) and remained stable in the DT arm, while the polyfunctionality of CD8+ T cells was unchanged in both arms. There was a significant decrease in the expression of PD-1, TIM-3, and the co-expression of PD-1+TIM-3+LAG-3+, and PD-1 +TIM-3 + in both CD4+ and CD8+ T cells. However, the decrease in the expression of exhaustion markers did not improve HIV-1-specific T-cell responses. CONCLUSIONS: Our results suggest that simplification to DT does not negatively influence the HIV-1-specific T-cell response or the exhaustion phenotype after 96 weeks of follow-up.


Assuntos
Fármacos Anti-HIV , Infecções por HIV , HIV-1 , Humanos , HIV-1/genética , Receptor Celular 2 do Vírus da Hepatite A/metabolismo , Linfócitos T CD8-Positivos , Inibidores de Integrase/metabolismo , Inibidores de Integrase/uso terapêutico , Infecções por HIV/tratamento farmacológico , Receptor de Morte Celular Programada 1/metabolismo , Fármacos Anti-HIV/uso terapêutico , Fármacos Anti-HIV/metabolismo
3.
J Antimicrob Chemother ; 78(9): 2354-2360, 2023 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-37545387

RESUMO

BACKGROUND: This was a substudy of a Phase IV, randomized clinical trial (ClinicalTrials.gov identifier: NCT04295460) aiming to compare the activity of dolutegravir/lamivudine versus dolutegravir plus tenofovir alafenamide/emtricitabine (DTG + TAF/FTC) in the male genital tract. METHODS: Participants were asymptomatic adults without sexually transmitted diseases, treatment-naive people living with HIV (PLWH), with CD4+ T cell counts >200 cells/mm3 and plasma HIV-1-RNA levels >5000 and <500 000 copies/mL, randomized (1:1) to DTG + TAF/FTC or dolutegravir/lamivudine. Blood plasma (BP) and seminal plasma (SP) were collected at baseline and Weeks 4, 8, 12 and 24. HIV-1-RNA was measured in BP and SP using the Cobas 6800 system (Roche Diagnostics) with a lower detection limit of 20 copies/mL. The primary efficacy endpoint was the proportion of subjects with undetectable SP HIV-1-RNA at Week 12 by intention-to-treat analysis. RESULTS: Fifteen participants in the DTG + TAF/FTC and 16 in the dolutegravir/lamivudine arms were analysed, with basal SP viral load of 4.81 (4.30-5.43) and 4.76 (4.09-5.23), P = 0.469, respectively. At Week 12, only one participant in each treatment arm had a detectable SP HIV-1-RNA (DTG + TAF/FTC, 141 copies/mL; dolutegravir/lamivudine, 61 copies/mL). Based on the estimated means, there was no significant difference in the decay of HIV-1-RNA in both BP and SP over time between the two arms of treatment (F = 0.452, P = 0.662, and F = 1.147, P = 0.185, respectively). CONCLUSIONS: After 12 weeks of treatment, there were no differences in the percentage of undetectable SP HIV-1-RNA in naive PLWH who started dolutegravir/lamivudine compared with DTG + TAF/FTC.


Assuntos
Fármacos Anti-HIV , Infecções por HIV , HIV-1 , Adulto , Humanos , Masculino , Lamivudina/uso terapêutico , HIV-1/genética , Infecções por HIV/tratamento farmacológico , Sêmen , Cinética , Quimioterapia Combinada , Emtricitabina/uso terapêutico , Compostos Heterocíclicos com 3 Anéis/uso terapêutico , Piridonas/uso terapêutico , Oxazinas/uso terapêutico , RNA Viral , Fármacos Anti-HIV/uso terapêutico
4.
Front Immunol ; 14: 1129753, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37006309

RESUMO

Background: Data on SARS-CoV-2 mRNA vaccine immunogenicity in people living with human immunodeficiency virus (PLWH) and discordant immune response (DIR) are currently limited. Therefore, we compare the immunogenicity of these vaccines in DIR and immunological responders (IR). Methods: A prospective cohort that enrolled 89 participants. Finally, 22 IR and 24 DIR were analyzed before vaccination (T0), one (T1) and six months (T2) after receiving BNT162b2 or mRNA-1273 vaccine. Additionally, 10 IR and 16 DIR were evaluated after a third dose (T3). Anti-S-RBD IgG, neutralizing antibodies (nAb), neutralization activity, and specific memory B cells were quantified. Furthermore, specific CD4+ and CD8+ responses were determined by intracellular cytokine staining and polyfunctionality indexes (Pindex). Results: At T1, all participants developed anti-S-RBD. 100% IR developed nAb compared to 83.3% DIR. Spike-specific B cells were detected in all IR and 21/24 DIR. Memory CD4+ T cells responded in 5/9 IR and 7/9 DIR, mainly based on the expression of IFN-γ and TNF-α, with a higher Pindex in DIR. Memory CD8+ T cells responded in only four participants in each group. At T2, anti-S-RBD and nAb titers were higher in DIR than in IR. In both groups, there was an increase in specific B memory cells, higher in DIR. Six IR and five DIR maintained a specific memory CD4+ response. Memory CD8+ response was preserved in IR but was lost in DIR. In a multivariate linear regression analysis, receiving mRNA-1273 instead of BNT162b2 played a prominent role in the results. Conclusions: Our data suggest that PLWH with DIR can mount an immune response similar to those with higher CD4+, provided they receive the mRNA-1273 vaccine instead of others less immunogenic.


Assuntos
COVID-19 , Vacinas , Humanos , Vacinas contra COVID-19 , Vacina BNT162 , Vacina de mRNA-1273 contra 2019-nCoV , SARS-CoV-2 , Linfócitos T CD8-Positivos , Estudos Prospectivos , COVID-19/prevenção & controle , Vacinação , Vacinas de mRNA , Imunidade Celular , Anticorpos Neutralizantes
5.
J Chromatogr A ; 1685: 463577, 2022 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-36323106

RESUMO

Magnetic ionic liquids (MILs) are materials of special interest in analytical chemistry and, particularly, in analytical microextraction. These solvents possess several of the properties derived from their inherent nature of ionic liquids, combined with their magnetism, that permits their manipulation with an external magnetic field. This feature allows for performing typical steps of the microextraction procedure in a simpler manner with the aid of a strong magnet. Although there are several important reviews summarizing the most innovative advances in this field, there is a gap of information, as they do not provide useful details and tips related to the experimental set up of these procedures. This tutorial review fills this gap by providing a guide for the proper handling of MILs, their manipulation with magnets, and their proper hyphenation with the most used analytical techniques. Attention is paid to dispersive liquid-liquid microextraction, stir-bar dispersive liquid microextraction, aqueous biphasic systems, and single-drop microextraction, for being the analytical microextraction techniques mostly employed with MILs. This review also introduces a classification of the MILs employed in analytical microextraction in three classes (denoted as A, B, and C) as a function of the MIL nature (metal-containing anion, metal-containing cation, and radical-containing ion), and discuss about the prospect and future trends regarding new MIL families in microextraction together with new directions expected in these procedures.


Assuntos
Líquidos Iônicos , Microextração em Fase Líquida , Humanos , Líquidos Iônicos/química , Microextração em Fase Líquida/métodos , Magnetismo , Solventes/química , Fenômenos Magnéticos
6.
PLoS One ; 17(7): e0269875, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35834501

RESUMO

BACKGROUND: The SARS-CoV-2 pandemic has overwhelmed hospital services due to the rapid transmission of the virus and its severity in a high percentage of cases. Having tools to predict which patients can be safely early discharged would help to improve this situation. METHODS: Patients confirmed as SARS-CoV-2 infection from four Spanish hospitals. Clinical, demographic, laboratory data and plasma samples were collected at admission. The patients were classified into mild and severe/critical groups according to 4-point ordinal categories based on oxygen therapy requirements. Logistic regression models were performed in mild patients with only clinical and routine laboratory parameters and adding plasma pro-inflammatory cytokine levels to predict both early discharge and worsening. RESULTS: 333 patients were included. At admission, 307 patients were classified as mild patients. Age, oxygen saturation, Lactate Dehydrogenase, D-dimers, neutrophil-lymphocyte ratio (NLR), and oral corticosteroids treatment were predictors of early discharge (area under curve (AUC), 0.786; sensitivity (SE) 68.5%; specificity (S), 74.5%; positive predictive value (PPV), 74.4%; and negative predictive value (NPV), 68.9%). When cytokines were included, lower interferon-γ-inducible protein 10 and higher Interleukin 1 beta levels were associated with early discharge (AUC, 0.819; SE, 91.7%; S, 56.6%; PPV, 69.3%; and NPV, 86.5%). The model to predict worsening included male sex, oxygen saturation, no corticosteroids treatment, C-reactive protein and Nod-like receptor as independent factors (AUC, 0.903; SE, 97.1%; S, 68.8%; PPV, 30.4%; and NPV, 99.4%). The model was slightly improved by including the determinations of interleukine-8, Macrophage inflammatory protein-1 beta and soluble IL-2Rα (CD25) (AUC, 0.952; SE, 97.1%; S, 98.1%; PPV, 82.7%; and NPV, 99.6%). CONCLUSIONS: Clinical and routine laboratory data at admission strongly predict non-worsening during the first two weeks; therefore, these variables could help identify those patients who do not need a long hospitalization and improve hospital overcrowding. Determination of pro-inflammatory cytokines moderately improves these predictive capacities.


Assuntos
COVID-19 , SARS-CoV-2 , Biomarcadores , Citocinas , Humanos , Masculino , Alta do Paciente
7.
AIDS ; 36(9): 1207-1214, 2022 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-35608119

RESUMO

OBJECTIVE: We aimed to evaluate the anti-CD4 IgG role in the poor immune recovery of immunological nonresponder people with HIV (INR). DESIGN: INR display low CD4 + T-cell increase despite long-term undetectable viremia. Among other factors, autologous anti-CD4 IgG-dependent cellular cytotoxicity (ADCC) by natural killer (NK) cells has been proposed to cause CD4 + T-cell depletion. METHODS: Plasma anti-CD4 IgG levels were quantified and purified by chromatography columns for the subsequent use in a coculture of CD4 + T and NK cells. We analyzed NK cell degranulation markers (CD107a, perforin and granzyme B) and IFN-γ release, and CD4 + T-cell death. Binding affinity of anti-CD4 IgG for CD4 + T cells was also assessed. RESULTS: A total of 168 individuals were enrolled (INR, 56; immunological responders, 40; treatment-naive, 39; and healthy controls, 33). The highest anti-CD4 IgG levels were found in treatment-naive people with HIV (PWH), followed by participants on treatment. There were no correlations between anti-CD4 IgG levels and CD4 + T-cell counts. In a 15-participant subgroup (naive, immunological responders, and INR), anti-CD4 IgG induced a slight NK-cell expression of degranulation markers and IFN-γ; however, the percentage of CD4 + T-cell death was negligible. Consistently, no significant changes in NK cell polyfunctionality were observed. In addition, purified anti-CD4 IgG showed scarce binding affinity for CD4 + T cells. These results were similar in all analyzed participant groups. CONCLUSION: Our results suggest that autologous anti-CD4 IgG neither trigger CD4 + T-cell death by ADCC nor are responsible for CD4 + lymphocyte depletion in INR.


Assuntos
Autoanticorpos , Infecções por HIV , Antígenos CD4/metabolismo , Contagem de Linfócito CD4 , Linfócitos T CD4-Positivos , Humanos , Imunoglobulina G , Depleção Linfocítica
8.
Clin Transl Med ; 12(4): e802, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35415890

RESUMO

SARS-CoV-2 specific T-cell response has been associated with disease severity, immune memory and heterologous response to endemic coronaviruses. However, an integrative approach combining a comprehensive analysis of the quality of SARS-CoV-2 specific T-cell response with antibody levels in these three scenarios is needed. In the present study, we found that, in acute infection, while mild disease was associated with high T-cell polyfunctionality biased to IL-2 production and inversely correlated with anti-S IgG levels, combinations only including IFN-γ with the absence of perforin production predominated in severe disease. Seven months after infection, both non-hospitalised and previously hospitalised patients presented robust anti-S IgG levels and SARS-CoV-2 specific T-cell response. In addition, only previously hospitalised patients showed a T-cell exhaustion profile. Finally, combinations including IL-2 in response to S protein of endemic coronaviruses were the ones associated with SARS-CoV-2 S-specific T-cell response in pre-COVID-19 healthy donors' samples. These results could have implications for protective immunity against SARS-CoV-2 and recurrent COVID-19 and may help for the design of new prototypes and boosting vaccine strategies.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Imunoglobulina G , Memória Imunológica , Interleucina-2 , Índice de Gravidade de Doença , Linfócitos T
9.
Clin Microbiol Infect ; 28(8): 1151.e9-1151.e16, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35289296

RESUMO

OBJECTIVES: To evaluate whether simplification of antiretroviral treatment to dual therapy (DT) negatively impacts immune recovery (IR), immune activation and inflammation (IA/I), and HIV reservoir. METHODS: An open-label, single-centre, randomized controlled trial conducted in adult virologically suppressed HIV-infected patients on triple therapy (TT) with elvitegravir-cobicistat, emtricitabine and tenofovir alafenamide or dolutegravir (DTG), abacavir, and lamivudine (3TC). Participants were randomized to continue TT or switch to DTG, or darunavir/cobicistat (DRVc) plus 3TC. IR was assessed by CD4+/CD8+ ratio at 48 and 96 weeks. Changes in immune activation, proliferation, exhaustion, senescence, and apoptosis in CD4+ and CD8+ T cells, plasma sCD14, hsCRP, D-dimers, ß2-microglobulin, IL-6, TNF-α and IP-10 levels, cell-associated HIV-DNA (CA-DNA), and unspliced HIV-RNA (usRNA) were also analysed. RESULTS: One hundred and fifty-one participants were enrolled. Fourteen patients did not complete the follow up. In the ITT and PP analysis, the IR was similar between the treatment arms. In the ITT analysis, the median increase in CD4+/CD8+ ratio was 0.10, 0.04, and 0.07 at week 48, and 0.09, 0.05, and 0.08 at week 96 for TT, DTG/3TC, and DRVc/3TC, respectively. After adjusting for confounding factors, the slopes of changes in CD4+/CD8+ ratio over time were independent of treatment (F = 1.699; p = 0.436) and related only to baseline values (F = 756.871; p = 0.000). There were no differences in IA/I, CA-DNA, or usRNA between treatment arms. DISCUSSION: Both IR and IA/I, CA-DNA, and usRNA were similar in the three treatment groups, regardless of maintaining TT or simplifying to DTG/3TC or DRVc/3TC in virologically suppressed HIV-infected patients.


Assuntos
Fármacos Anti-HIV , Infecções por HIV , Adulto , Linfócitos T CD8-Positivos , Cobicistat/uso terapêutico , Infecções por HIV/tratamento farmacológico , Compostos Heterocíclicos com 3 Anéis , Humanos , Lamivudina/uso terapêutico , Carga Viral
10.
Sci Total Environ ; 826: 154027, 2022 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-35217040

RESUMO

Notwithstanding the fact that microplastic fragments were encountered in the human stool, little effort has been geared towards elucidating the impact of chemical additives upon the human health. In this work, standardized bioaccessibility tests under both fasting and fed conditions are herein applied to the investigation of human oral bioaccessibility of plastic additives and monomers (i.e. eight phthalate esters (PAEs) and bisphenol A (BPA)) in low-density polyethylene (LDPE) and polyvinyl chloride (PVC) microplastics. The generation of phthalate monoesters is evaluated in the time course of the bioaccessibility tests. Maximum gastric and gastrointestinal bioaccessibility fractions are obtained for dimethyl phthalate, diethyl phthalate and BPA, within the range of 55-83%, 40-68% and 37-67%, respectively, increasing to 56-92% and 41-70% for dimethyl phthalate and diethyl phthalate, respectively, whenever their hydrolysis products are considered. Bioaccessibility fractions of polar PAEs are dependent upon the physicochemical characteristics of the microplastics, with greater bioaccessibility for the rubbery polymer (LDPE). With the method herein proposed, oral bioaccessible pools of moderately to non-polar PAEs can be also accurately assessed for risk-assessment explorations, with values ranging from 1.8% to 32.2%, with again significantly larger desorption percentages for LDPE. Our results suggested that the highest gastric/gastrointestinal bioaccessibility of the eight PAEs and BPA is reached under fed-state gastrointestinal extraction conditions because of the larger amounts of surface-active biomolecules. Even including the bioaccessibility factor within human risk assessment/exposure studies to microplastics, concentrations of dimethyl phthalate, di-n-butyl phthalate and BPA exceeding 0.3% (w/w) may pose severe risks after oral uptake in contrast to the more hydrophobic congeners for which concentrations above 3% (w/w), except for diethylhexyl phthalate, would be tolerated.


Assuntos
Microplásticos , Ácidos Ftálicos , Compostos Benzidrílicos , Dibutilftalato , Ingestão de Alimentos , Ésteres , Jejum , Humanos , Fenóis , Plásticos , Polietileno
11.
Microorganisms ; 9(11)2021 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-34835384

RESUMO

Viral and host immune kinetics during acute COVID-19 and after remission of acute symptoms need better characterization. SARS-CoV-2 RNA, anti-SARS-CoV-2 IgA, IgM, and IgG antibodies, and proinflammatory cytokines were measured in sequential samples from hospitalized COVID-19 patients during acute infection and six months following diagnosis. Twenty four laboratory confirmed COVID-19 patients with mild/moderate and severe COVID-19 were included. Most were males (83%) with a median age of 61 years. Twenty one percent were admitted to the intensive care unit (ICU) and eight of them (33.3%) met the criteria for severe COVID-19 disease. A delay in SARS-CoV-2 levels' decline during the first six days of follow up, and viral load persistence until month 3 were related to severe COVID-19, but not viral load levels at the diagnosis. Higher levels of anti-SARS-CoV-2 IgA, IgM, IgG and the cytokines IL-6, IL-8 and MIP-1ß at the diagnosis time were related to the severe COVID-19 outcome. Higher levels of MIP-1ß, IL-1ß, MIP-1α and IFN-γ were observed at month 1 and 3 during mild/moderate disease, compared to severe COVID-19. IgG persisted at low levels after six months of diagnosis. In conclusion, higher concentrations of IgA, IgM, and IgG, and IL-6, IL-8 and MIP-1ß are identified as early predictors of COVID-19 severity, whereas no significant association is found between baseline SARS-COV-2 viral load and COVID-19 severity.

12.
Cell Mol Immunol ; 18(9): 2128-2139, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34290398

RESUMO

Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV)-2 infection induces an exacerbated inflammation driven by innate immunity components. Dendritic cells (DCs) play a key role in the defense against viral infections, for instance plasmacytoid DCs (pDCs), have the capacity to produce vast amounts of interferon-alpha (IFN-α). In COVID-19 there is a deficit in DC numbers and IFN-α production, which has been associated with disease severity. In this work, we described that in addition to the DC deficiency, several DC activation and homing markers were altered in acute COVID-19 patients, which were associated with multiple inflammatory markers. Remarkably, previously hospitalized and nonhospitalized patients remained with decreased numbers of CD1c+ myeloid DCs and pDCs seven months after SARS-CoV-2 infection. Moreover, the expression of DC markers such as CD86 and CD4 were only restored in previously nonhospitalized patients, while no restoration of integrin ß7 and indoleamine 2,3-dyoxigenase (IDO) levels were observed. These findings contribute to a better understanding of the immunological sequelae of COVID-19.


Assuntos
COVID-19/imunologia , Células Dendríticas/imunologia , SARS-CoV-2/imunologia , Células Cultivadas , Feminino , Humanos , Imunidade Inata/imunologia , Inflamação/imunologia , Interferon-alfa/imunologia , Leucócitos Mononucleares/imunologia , Masculino , Índice de Gravidade de Doença
13.
Analyst ; 146(12): 3858-3870, 2021 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-34047317

RESUMO

This article reports on the first attempt towards investigating the leaching rates in the human gastrointestinal (GI) tract of plastic-borne contaminants that can be ingested accidentally using physiologically relevant body fluids. Oral bioaccessibility under fasted and fed states was determined in dynamic mode exploiting an automatic flow setup. The flow system is able to mimic the fast uptake of the released species from the polymeric matrix by absorption in the human digestive system by the in-line removal of the leached species. Complex GI extractants based on the Unified Bioaccessibility Method (UBM, fasted state) and Versantvoort test (fed-state) were brought through a microplastic-loaded metal microcolumn for semi-continuous leaching of plasticizers (phthalic acid ester congeners) and monomer/antioxidant species (bisphenol A, BPA) followed by in-line solid-phase extraction and clean-up of GI extracts prior to liquid chromatography analysis. The temporal extraction profiles were fitted to a first-order kinetic model for the estimation of maximum bioaccessibility pools and apparent leaching rates. Among all studied contaminants, only BPA, dimethylphthalate and diethylphthalate were appreciably released under dynamic GI conditions from high-density polyethylene pellets (average size of 110 µm), with average bioaccessibility values spanning from 51 to 84% and 48 to 87% for UBM and Versantvoort methods, respectively. No statistically significant differences in oral bioaccessibility pools were found under fed- and fasted-state dynamic extractions. The apparent kinetic constants under the fed state were greater by ≥30% as a consequence of the effect of the larger amounts of bile salts and digestive enzymes in the Versantvoort test on the leaching rates. The estimated average daily intake, in which bioaccessibility data are contemplated, indicated that plastic materials exceeding 0.3% (w/w) BPA might pose real risks to human health.


Assuntos
Disruptores Endócrinos , Poluentes do Solo , Disponibilidade Biológica , Humanos , Cinética , Microplásticos , Plásticos , Poluentes do Solo/análise , Extração em Fase Sólida
14.
Stem Cells Transl Med ; 10(4): 534-541, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33264515

RESUMO

Between 15% and 30% of HIV-infected subjects fail to increase their CD4+ T-cell counts despite continuous viral suppression (immunological nonresponders [INRs]). These subjects have a higher morbidity and mortality rate, but there are no effective treatments to reverse this situation so far. This study used data from an interrupted phase I/II clinical trial to evaluate safety and immune recovery after INRs were given four infusions, at baseline and at weeks 4, 8, and 20, with human allogeneic mesenchymal stromal cells from adipose tissue (Ad-MSCs). Based on the study design, the first 5 out of 15 INRs recruited received unblinded Ad-MSC infusions. They had a median CD4+ nadir count of 16/µL (range, 2-180) and CD4+ count of 253 cells per microliter (171-412) at baseline after 109 (54-237) months on antiretroviral treatment and 69 (52-91) months of continuous undetectable plasma HIV-RNA. After a year of follow-up, an independent committee recommended the suspension of the study because no increase of CD4+ T-cell counts or CD4+ /CD8+ ratios was observed. There were also no significant changes in the phenotype of different immunological lymphocyte subsets, percentages of natural killer cells, regulatory T cells, and dendritic cells, the inflammatory parameters analyzed, and cellular associated HIV-DNA in peripheral blood mononuclear cells. Furthermore, three subjects suffered venous thrombosis events directly related to the Ad-MSC infusions in the arms where the infusions were performed. Although the current study is based on a small sample of participants, the findings suggest that allogeneic Ad-MSC infusions are not effective to improve immune recovery in INR patients or to reduce immune activation or inflammation. ClinicalTrials.gov identifier: NCT0229004. EudraCT number: 2014-000307-26.


Assuntos
Infecções por HIV , Transplante de Células-Tronco Mesenquimais , Tecido Adiposo/citologia , Contagem de Linfócito CD4 , Término Precoce de Ensaios Clínicos , HIV , Infecções por HIV/imunologia , Infecções por HIV/terapia , Humanos , Leucócitos Mononucleares , Falha de Tratamento
15.
Environ Pollut ; 272: 115992, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33246769

RESUMO

The unified bioaccessibility method (UBM) was harnessed to assess in vitro oral bioaccessibility pools of dialkyl phthalate congeners (with methyl, -ethyl, -butylbenzyl, -n-butyl, -2-ethylhexyl, and -n-octyl moieties) and bisphenol A at the 17 µg g-1 level in beach sand contaminated with polyethylene microplastics. A variety of sample preparation approaches prior to the analysis of the UBM gastrointestinal extracts, including traditional methods (protein precipitation, liquid-liquid extraction, and solid-phase extraction) and dispersive liquid-liquid microextraction (DLLME) were comprehensively evaluated for clean-up and analyte enrichment. DLLME was chosen among all tested approaches on account of the high extraction efficiency (73-95%, excluding bis(2-ethylhexyl)phthalate and di-n-octyl phthalate), high sample throughput (∼7 min per set of samples), and environmental friendliness as demonstrated by the analytical eco-scale score of 83, and the green analytical procedure index pictogram with green/yellow labeling. The release of the less hydrophobic plastic-laden compounds (dimethyl phthalate, diethyl phthalate and bisphenol A) from the contaminated sample into the body fluids was significant, with bioaccessibility values ranging from 30 to 70%, and from 43 to 74% in gastric and gastrointestinal fluids, respectively, and with relative standard deviation < 17% in all cases. The majority of the compounds were leached during gastric digestion, likely as the combined action of the low pH and the gastric enzymes. The risk exposure analysis revealed that accumulation/concentration in the body fluids is potentially relevant for dimethyl phthalate, diethyl phthalate and bisphenol A, with relative accumulation ratios ranging from 1.1 ± 0.1 to 2.6 ± 0.4. The average daily intake values for the suite of compounds, corrected with the bioaccessibility fraction, ranged from 60 to 430 ng kg of body weight-1·day-1, in all cases, far below the tolerable daily intakes, thus indicating the lack of children health risk by ingestion of microplastic-laden sand with elevated concentrations of plasticizers.


Assuntos
Disruptores Endócrinos , Ácidos Ftálicos , Criança , Humanos , Microplásticos , Extratos Vegetais , Plásticos , Areia
16.
J Chromatogr A ; 1634: 461670, 2020 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-33197845

RESUMO

This review overviews the main developments achieved in analytical sample preparation regarding the use of solid sorbents as extractants in different sorbent-based miniaturized, micro-scale and microextraction methods. Two main groups are proposed for the classification of the current approaches, based on their operational mode: micro-solid-phase extraction (µ-SPE) and solid-phase microextraction (SPME), while describing their respective main sub-modes: static- and dispersive-µ-SPE, and SPME with fibers and in tube SPME. Furthermore, other important sorbent-based microscale approaches (e.g., stir bar sorptive extraction, stir cake sorptive extraction, stir bar sorptive-dispersive microextraction, and thin film microextraction, among others) are also considered.


Assuntos
Microextração em Fase Sólida/métodos , Microextração em Fase Sólida/tendências , Absorção Fisico-Química
17.
Artigo em Inglês | MEDLINE | ID: mdl-32571815

RESUMO

The activation phenotypes and functional changes in monocyte subsets during hepatitis C virus (HCV) elimination in HIV/HCV-coinfected patients were evaluated. Twenty-two HIV/HCV-coinfected patients on suppressive combination antiretroviral treatment (cART) achieving HCV elimination after direct-acting antiviral (DAA) therapy and 10 HIV-monoinfected patients were included. The activation phenotype (10 markers) and polyfunctionality (intracellular interleukin-1α [IL-1α], IL-1ß, IL-6, IL-8, tumor necrosis factor alpha [TNF-α], and IL-10 production) in three monocyte subsets (classical, intermediate, and nonclassical) were evaluated by flow cytometry before and at the end of treatment. Cell-associated HIV DNA levels were assayed by droplet digital PCR. After HCV clearance, there was a significant increase in classical monocyte and decreases in intermediate and nonclassical monocyte levels. The levels of the activation markers CD49d, CD40, and CX3CR1 were decreased after treatment in the monocyte subsets, reaching the levels in HIV-monoinfected patients. After lipopolysaccharide (LPS) stimulation, although polyfunctionality significantly decreased in intermediate and nonclassical monocytes, some combinations, such as the IL-1α- (IL-1α-negative) IL-1ß- IL-6+ (IL-6-producing) IL-8- TNF-α- IL-10- combination, were remarkably increased at the end of treatment compared to the control group. Cell-associated HIV DNA levels correlated with activation markers before but not after treatment. HCV clearance after DAA treatment in patients on cART exerts an anti-inflammatory profile on monocyte subsets, activation phenotypes, and polyfunctionality. However, there is not a complete normalization compared with HIV-monoinfected patients.


Assuntos
Coinfecção , Infecções por HIV , Hepatite C Crônica , Hepatite C , Antivirais/uso terapêutico , Coinfecção/tratamento farmacológico , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Hepacivirus , Hepatite C/tratamento farmacológico , Hepatite C Crônica/tratamento farmacológico , Humanos , Monócitos
18.
Anal Bioanal Chem ; 412(12): 2743-2754, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32322952

RESUMO

Magnetic ionic liquids (MILs) with metal-containing cations are promising extraction solvents that provide fast and high efficiency extraction of DNA. Hydrophobic MILs can be generated in situ in a methodology called in situ dispersive liquid-liquid microextraction. To consolidate the sample preparation workflow, it is desirable to directly use the DNA-enriched MIL microdroplet in the subsequent analytical detection technique. Fluorescence-based techniques employed for DNA detection often utilize SYBR Green I, a DNA binding dye that exhibits optimal fluorescence when bound to double-stranded DNA. However, the MIL may hinder the fluorescence signal of the SYBR Green I-dsDNA complex due to quenching. In this study, MILs with metal-containing cations were selected and their fluorescence quenching effects evaluated using FÓ§rster Resonance Energy Transfer and quantified using Stern-Volmer models. The MILs were based on N-substituted imidazole ligands (with butyl- and benzyl- groups as substituents) coordinated to Ni2+ or Co2+ metal centers as cations, and paired with chloride anions. The effects of NiCl2 and CoCl2 salts and of the 1-butyl-3-methylimidazolium chloride ionic liquid on the fluorophore complex were also studied to understand the components of the MIL structure that are responsible for quenching. The metal within the MIL chemical structure was found to be the main component contributing to fluorescence quenching. FÓ§rster critical distances between 11.9 and 18.8 Å were obtained for the MILs, indicating that quenching is likely not due to non-radiative energy transfer but rather to spin-orbit coupling or excited-state electron transfer. The MILs were able to be directly used in qPCR and fluorescence emission measurements using a microplate reader for detection, demonstrating their applicability in fluorescence-based detection methods. Graphical abstract.


Assuntos
DNA/análise , Fluorescência , Líquidos Iônicos , Magnetismo , Compostos Orgânicos/metabolismo , Benzotiazóis , DNA/química , DNA/metabolismo , Diaminas , Humanos , Interações Hidrofóbicas e Hidrofílicas , Compostos Orgânicos/química , Quinolinas , Solventes
19.
J Sep Sci ; 43(9-10): 1890-1907, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32074395

RESUMO

Ionic liquids and derivatives-mainly polymeric ionic liquids and magnetic ionic liquids-have been extensively used in microscale extraction over the past few years. Current trends in analytical sample preparation gear toward linking microextraction approaches with high-throughput sample processing to comply with green analytical chemistry requirements. A variety of high sample throughput strategies that are coupled to both ionic-liquid-based solid-phase microextraction and ionic liquid-based liquid-phase microextraction are herein reported. The review is focused on microscale extraction methods that use (i) custom-made and dedicated extraction devices, (ii) parallel extraction, (iii) magnetic-based separation, and (iv) miniaturized systems employing semi-automatic or fully automatic flow injection methods, related micro/millifluidic devices, and robotic equipment.

20.
Talanta ; 208: 120390, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31816753

RESUMO

Vacuum-assisted sorbent extraction (VASE) has been applied in combination with gas chromatography-mass spectrometry for the determination of UV filters in water samples. VASE is a variant of headspace extraction which was developed in conjunction with the sorbent pen (SP) technology. This technique combines the advantages of both stir-bar assisted extraction and headspace solid-phase microextraction. The SP traps allowed both reduced pressure in-vial extraction and direct thermal desorption via a unique gas chromatographic injection port. The main parameters that affect the performance of VASE, including both extraction and desorption conditions, were extensively optimized. Under optimum conditions, extraction required 10 mL of sample within 40 mL vials, pH 3.5, ~30 s of air-evacuation, 14 h incubation at 70 °C, stirring at 200 rpm, and a final water management step conducted at ~ -17 °C for 15 min. Optimal thermal desorption required preheating at 260 °C for 2 min followed by desorption at 300 °C for 2 min. The beneficial effect of reduced-pressure extraction was demonstrated by comparing the UV filter extraction time profiles collected using VASE to an analogous atmospheric pressure procedure, resulting in up to a 3-fold improvement under optimized conditions. The VASE methodology enabled simultaneous extractions using different SPs without compromising the method reproducibility, which increases the overall sample throughput. The method was characterized by low limits of detection, from 0.5 to 80 ng L-1, and adequate reproducibility, with inter-SP and inter-day relative standard deviation lower than 14%. Tap and lake water was successfully analyzed with the proposed methodology, resulting in relative recoveries of spiked samples ranging between 70.0 and 120%.

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