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1.
Int J Mol Sci ; 24(21)2023 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-37958698

RESUMO

Antimicrobial resistance is a silent pandemic considered a public health concern worldwide. Strategic therapies are needed to replace antibacterials that are now ineffective. One approach entails the use of well-known antibacterials along with adjuvants that possess non-antibiotic properties but can extend the lifespan and enhance the effectiveness of the treatment, while also improving the suppression of resistance. In this regard, a group of uniform materials based on organic salts (GUMBOS) presents an alternative to this problem allowing the combination of antibacterials with adjuvants. Fluoroquinolones are a family of antibacterials used to treat respiratory and urinary tract infections with broad-spectrum activity. Ciprofloxacin and moxifloxacin-based GUMBOS were synthesized via anion exchange reactions with lithium and sodium salts. Structural characterization, thermal stability and octanol/water partition ratios were evaluated. The antibacterial profiles of most GUMBOS were comparable to their cationic counterparts when tested against Gram-positive S. aureus and Gram-negative E. coli, except for deoxycholate anion, which demonstrated the least effective antibacterial activity. Additionally, some GUMBOS were less cytotoxic to L929 fibroblast cells and non-hemolytic to red blood cells. Therefore, these agents exhibit promise as an alternative approach to combining drugs for treating infections caused by resistant bacteria.


Assuntos
Fluoroquinolonas , Sais , Fluoroquinolonas/farmacologia , Sais/farmacologia , Sais/química , Escherichia coli , Staphylococcus aureus , Antibacterianos/química , Ânions , Testes de Sensibilidade Microbiana
2.
J Endocrinol Invest ; 45(12): 2257-2264, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35821458

RESUMO

AIM: Women with early-onset gestational diabetes mellitus (GDM) have overall lower gestational weight gain (GWG) compared to those with later-onset GDM, albeit with usually worse maternofetal outcomes. We intent to investigate the association between inadequate GWG and maternofetal outcomes in pregnant women with early-onset GDM. METHODS: We performed a retrospective study of women with early-onset GDM based on the National Registry of GDM. Three study groups were defined according to the recommendations of the Institute of Medicine for GWG: excessive GWG (eGWG), adequate (aGWG) or insufficient (iGWG). RESULTS: A total of 8040 pregnant women were included: 27% (n = 2170) eGWG, 31% (n = 2492) aGWG and 42% (n = 3378) iGWG. Preeclampsia (4.3 vs 3 vs 1.6%, p < 0.001), polyhydramnios (3.1 vs 2.3 vs 1.8%, p = 0.008) and cesarean section (37.4 vs 34.1 vs 29.5%, p < 0.001) were significantly more frequent among women with eGWG. Additionally, there was a higher frequency of macrosomia (8.1 vs 3.6 vs 2.4%, p < 0.001), large-for-gestational-age (8.2 vs 3.7 vs 2.6%, p < 0.001) and birth trauma (2.6 vs 1.5 vs 1.1%, p < 0.001) in this group. On the other hand, fetal death (0.2 vs 0.2 vs 0.5%, p = 0.04), small-for-gestational-age (9 vs 10.3 vs 14.9, p < 0.001) and preterm delivery (5.6 vs 7.1 vs 7.5%, p = 0.03) were more frequent in iGWG group. CONCLUSIONS: Over two-thirds of pregnant women with early-onset GDM had inappropriate GWG, which was significantly associated with adverse maternofetal outcomes. Weight management must be a focus of special attention in women with early-onset GDM, beyond glycemic control, to achieve healthy pregnancy outcomes.


Assuntos
Diabetes Gestacional , Recém-Nascido , Feminino , Gravidez , Humanos , Diabetes Gestacional/epidemiologia , Estudos Retrospectivos , Cesárea , Índice de Massa Corporal , Aumento de Peso , Resultado da Gravidez/epidemiologia
3.
Lett Appl Microbiol ; 74(5): 831-838, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35138674

RESUMO

Considering that plasmid conjugation is a major driver for the dissemination of antimicrobial resistance in bacteria, this study aimed to investigate the effects of residual concentrations of antimicrobial growth promoters (AGPs) in poultry litter on the frequencies of IncFII-FIB plasmid conjugation among Escherichia coli organisms. A 2 × 5 factorial trial was performed in vitro, using two types of litter materials (sugarcane bagasse and wood shavings) and five treatments of litter: non-treated (CON), herbal alkaloid sanguinarine (SANG), AGPs monensin (MON), lincomycin (LCM) and virginiamycin (VIR). E. coli H2332 and E. coli J62 were used as donor and recipient strains, respectively. The presence of residues of monensin, lincomycin and virginiamycin increased the frequency of plasmid conjugation among E. coli in both types of litter materials. On the contrary, sanguinarine significantly reduced the frequency of conjugation among E. coli in sugarcane bagasse litter. The conjugation frequencies were significantly higher in wood shavings compared with sugarcane bagasse only in the presence of AGPs. Considering that the presence of AGPs in the litter can increase the conjugation of IncFII-FIB plasmids carrying antimicrobial resistance genes, the real impact of this phenomenon on the dissemination of antimicrobial resistant bacteria in the poultry production chain must be investigated.


Assuntos
Anti-Infecciosos , Infecções por Escherichia coli , Saccharum , Animais , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Celulose/farmacologia , Conjugação Genética , Escherichia coli/genética , Infecções por Escherichia coli/microbiologia , Lincomicina/farmacologia , Monensin , Plasmídeos/genética , Aves Domésticas/microbiologia , Virginiamicina/farmacologia
4.
J Enzyme Inhib Med Chem ; 37(1): 1527-1536, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35635138

RESUMO

A novel automated method based on sequential injection analysis (SIA), a non-segmented flow injection technique, was developed to evaluate glutathione S-transferase P1-1 (GST P1-1) activity in the presence of organometallic complexes with putative anticancer activity. The assay is based on the reaction of L-glutathione (GSH) and 1-chloro-2,4-dinitrobenzene (CDNB) in the presence of GST P1-1 to afford the GS-DNB conjugate and the reaction may be monitored by an increase in absorbance at 340 nm. A series of ruthenium, iron, osmium and iridium complexes were evaluated as GST P1-1 inhibitors by evaluating their half-maximal inhibitory concentration (IC50). An iridium compound displays the lowest IC50 value of 6.7 ± 0.7 µM and an iron compound displays the highest IC50 value of 275 ± 9 µM. The SIA method is simple to use, robust, reliable, and efficient and uses fewer reagents than batch methods and each analysis takes only 5 minutes.


Assuntos
Glutationa Transferase , Compostos Organometálicos , Glutationa , Glutationa S-Transferase pi , Irídio , Compostos Organometálicos/farmacologia
5.
Tech Coloproctol ; 26(11): 893-900, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35986806

RESUMO

BACKGROUND: High-resolution anoscopy (HRA) is the gold standard for detecting anal squamous cell cancer (ASCC) precursors. Although it is superior to other diagnostic methods, particularly cytology, the visual identification of areas suspected of having high-grade squamous intraepithelial lesions remains difficult. Convolutional neural networks (CNNs) have shown great potential for assessing endoscopic images. The aim of the present study was to develop a CNN-based system for automatic detection and differentiation of HSIL versus LSIL in HRA images. METHODS: A CNN was developed based on 78 HRA exams from a total of 71 patients who underwent HRA at a single high-volume center (GH Paris Saint-Joseph, Paris, France) between January 2021 and January 2022. A total of 5026 images were included, 1517 images containing HSIL and 3509 LSIL. A training dataset comprising 90% of the total pool of images was defined for the development of the network. The performance of the CNN was evaluated using an independent testing dataset comprising the remaining 10%. The sensitivity, specificity, accuracy, positive and negative predictive values, and area under the curve (AUC) were calculated. RESULTS: The algorithm was optimized for the automatic detection of HSIL and its differentiation from LSIL. Our model had an overall accuracy of 90.3%. The CNN had sensitivity, specificity, positive and negative predictive values of 91.4%, 89.7%, 80.9%, and 95.6%, respectively. The area under the curve was 0.97. CONCLUSIONS: The CNN architecture for application to HRA accurately detected precursors of squamous anal cancer. Further development and implementation of these tools in clinical practice may significantly modify the management of these patients.


Assuntos
Neoplasias do Ânus , Carcinoma de Células Escamosas , Lesões Intraepiteliais Escamosas , Neoplasias do Ânus/diagnóstico por imagem , Neoplasias do Ânus/patologia , Inteligência Artificial , Carcinoma de Células Escamosas/diagnóstico por imagem , Carcinoma de Células Escamosas/patologia , Humanos , Redes Neurais de Computação
6.
Avian Pathol ; : 1-12, 2021 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-33779420

RESUMO

Salmonella enterica serovars use self-induced intestinal inflammation to increase electron acceptor availability and to obtain a growth advantage in the host gut. There is evidence suggesting that the ability of Salmonella to use tetrathionate and 1,2-propanediol provides an advantage in murine infection. Thus, we present here the first study to evaluate both systemic infection and faecal excretion in commercial poultry challenged by Salmonella Enteritidis (SE) and S. Typhimurium (STM) harbouring deletions in ttrA and pduA genes, which are crucial to the metabolism of tetrathionate and 1,2-propanediol, respectively. Mutant strains were excreted at higher rates when compared to the wild-type strains. The highest rates were observed with white egg-layer and brown egg-layer chicks (67.5%), and broiler chicks (56.7%) challenged by SEΔttrAΔpduA, and brown egg-layer chicks (64.8%) challenged by STMΔttrAΔpduA. SEΔttrAΔpduA presented higher bacterial counts in the liver and spleen of the three chicken lineages and caecal contents from the broiler chickens, whereas STMΔttrAΔpduA presented higher counts in the liver and spleen of the broiler and brown-egg chickens for 28 days post-infection (P < 0.05). The ttrA and pduA genes do not appear to be major virulence determinants in faecal excretion or invasiveness for SE and STM in chickens. RESEARCH HIGHLIGHTSttrA and pudA do not impair gut colonization or systemic infection in chicks.Mutant strains were present in higher numbers in broilers than in laying chicks.Mutants of SE and STM showed greater pathogenicity in broiler chicks than layers.

7.
Tech Coloproctol ; 25(11): 1243-1248, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34499277

RESUMO

BACKGROUND: Colon capsule endoscopy (CCE) is a minimally invasive alternative for patients unwilling to undergo conventional colonoscopy, or for whom the latter exam is contraindicated. This is particularly important in the setting of colorectal cancer screening. Nevertheless, these exams produce large numbers of images, and reading them is a monotonous and time-consuming task, with the risk of overlooking important lesions. The development of automated tools based on artificial intelligence (AI) technology may improve some of the drawbacks of this diagnostic instrument. METHODS: A database of CCE images was used for development of a Convolutional Neural Network (CNN) model. This database included anonymized images of patients with protruding lesions in the colon or patients with normal colonic mucosa or with other pathologic findings. A total of 3,387,259 frames from 24 CCE exams were retrospectively reviewed. For CNN development, 3640 images (860 protruding lesions and 2780 with normal mucosa or other findings) were ultimately extracted. Training and validation datasets were constructed for the development and testing of the CNN. RESULTS: The CNN detected protruding lesions with a sensitivity, specificity, positive and negative predictive values of 90.7, 92.6, 79.2 and 96.9%, respectively. The area under the receiver operating characteristic curve for detection of protruding lesions was 0.97. CONCLUSIONS: The deep learning algorithm we developed is capable of accurately detecting protruding lesions. The application of AI technology to CCE may increase its diagnostic accuracy and acceptance for screening of colorectal neoplasia.


Assuntos
Endoscopia por Cápsula , Neoplasias Colorretais , Inteligência Artificial , Colo/diagnóstico por imagem , Colonoscopia , Neoplasias Colorretais/diagnóstico por imagem , Humanos , Estudos Retrospectivos
8.
Molecules ; 26(1)2021 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-33401768

RESUMO

Human neutrophil elastase (HNE) is used as diagnostic biomarker for inflammation/infection. In this work, 10 ionic liquids (ILs) and 11 ionic liquids active pharmaceutical ingredients (ILs-APIs) were tested to evaluate the inhibition effect on the activity of porcine pancreatic elastase enzyme, frequently employed as a model for HNE. The insertion of ionic liquids in some drugs is useful, as the insertion of ILs with inhibitory capacity will also slow down all processes in which this enzyme is involved. Therefore, a spectrophotometric method was performed to the determination of EC50 values of the compounds tested. EC50 values of 124 ± 4 mM to 289 ± 11 mM were obtained, with the most toxic IL for elastase being tetrabutylammonium acetate and the least toxic 1-butyl-3-methylimidazolium acetate. Moreover, sodium salicylate (raw material) presented the lower and benzethonium bistriflimide the higher EC50 when compared with all the IL-APIs tested. This work provides significant information about the effect of the studied IL and IL-APIs in elastase enzyme activity.


Assuntos
Líquidos Iônicos/química , Líquidos Iônicos/farmacologia , Elastase Pancreática/antagonistas & inibidores , Inibidores de Serina Proteinase/química , Inibidores de Serina Proteinase/farmacologia , Compostos de Anilina/metabolismo , Animais , Imidazóis/química , Imidazóis/farmacologia , Líquidos Iônicos/toxicidade , Elastase Pancreática/metabolismo , Compostos de Amônio Quaternário/química , Compostos de Amônio Quaternário/farmacologia , Salicilato de Sódio/farmacologia , Relação Estrutura-Atividade , Suínos
9.
Analyst ; 145(7): 2701-2708, 2020 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-32072997

RESUMO

In this work, two solid-phases based on imidazolium-based ionic liquids were obtained and characterized for solid-phase extraction of fluoroquinolones. The process of immobilization was performed replacing a toxic reagent by UV-irradiation to get a harmless process. The obtained solid-phases were characterized by nuclear magnetic resonance spectroscopy and elemental analysis. Each solid-phase was packed in a cartridge and was used in solid-phase extraction processes for norfloxacin and ciprofloxacin, after the optimization of some parameters such as the elution solvent, the eluent volume and, the sample volume to be used during the loading step. The developed solid-phases with immobilized ionic liquids were successfully implemented for the studied compounds and indicate high probabilities to be useful in solid-phase extractions of other fluoroquinolones.

10.
Int Endod J ; 53(3): 354-365, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31581318

RESUMO

AIM: To evaluate the specific role of ICAM-1 in host responses against endodontic infection. METHODS: Apical periodontitis was experimentally induced in the mandibular first molars of ICAM-1 knockout and wild-type (WT) mice by pulp exposure to the oral environment. At 7, 21 and 42 days following pulp infection, the animals were euthanized and the jaws were prepared for analysis under conventional and fluorescence microscopy (histopathologic and morphometric analysis), immunohistochemistry (polymorphonuclear leucocytes), enzyme histochemistry (osteoclasts and cementoclasts) and RT-PCR (IL-1 α, TNF-α, INF-γ, IL-10, RANK, RANKL and OPG). A generalized linear model with GLIMMIX procedure with Satterthwaite approximation method of degrees of freedom, Tukey-Kramer, pseudo-ranking nonparametric, Bonferroni-Holm multiple testing adjustment, analysis of variance (ANOVA) and the Tukey's multiple comparisons tests were used to evaluate the statistical differences between the groups using SAS 9.4 and the GraphPad Prism 5.0 software (α = 0.05). RESULTS: Compared to WT mice, ICAM-1 knockout mice had significantly greater bone resorption (P < 0.05), reduced recruitment of neutrophils to periapical inflammatory tissues (P < 0.05) and an increased number of fibroblasts (P < 0.05) at all experimental periods. The osteoclast number was significantly higher in ICAM-1 KO than that of WT animals at all times (P < 0.05), while there was no significant difference between the groups regarding cementoclasts. At day 21, the level of IL-1α, RANK, RANKL and IL-10 had increased significantly in tissues from ICAM-1 KO versus WT mice (P < 0.05), while no significant difference was observed in TNF-α and OPG levels (P > 0.05). Tissue levels of INF-γ were significantly lower in ICAM-1 KO than those in WT mice (P < 0.05). CONCLUSION: ICAM-1 deficiency impaired the host response against endodontic infection, resulting in increased tissue destruction.


Assuntos
Molécula 1 de Adesão Intercelular , Periodontite Periapical , Animais , Camundongos , Camundongos Knockout , Osteoclastos , Fator de Necrose Tumoral alfa
11.
Int Endod J ; 53(8): 1111-1119, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32344454

RESUMO

AIM: To investigate the presence, localization and the possible correlation of the fibroblast growth factor receptor-2 (FGFR2) with inflammatory resorption of cementum, periodontal ligament and alveolar bone during development of apical periodontitis in mice. METHODOLOGY: Apical periodontitis was experimentally induced in mandibular first molars of mice by pulp exposure to the oral environment. Healthy teeth without pulp exposure were used as controls. At 7, 21 and 42 days following pulp exposure, the animals were euthanized and the jaws were prepared for analysis under conventional and fluorescence microscopy, immunohistochemistry (FGFR2), RT-PCR (RNAm levels of RANK, RANKL, OPG, Runx2 and cathepsin K) and enzyme histochemistry (cementoclasts and osteoclasts). Statistical analysis was performed by Kruskal-Wallis tests and Dunn's post hoc tests for multiple comparisons (α = 0.05) using SAS 9.4 software. RESULTS: FGFR2-positive cells were not observed in the tissues surrounding healthy teeth but were observed in teeth with periapical lesions from seven days after root canal contamination. At days 21 and 42 after endodontic infection, the increase in periapical lesion size was accompanied by significantly enhanced expression of FGFR2 (P < 0.0001), significantly increased intensity of inflammatory cells, number of osteoclasts (P < 0.0001) and cementoclasts (P < 0.0001), and significantly enhanced RNAm levels of RANK/RANKL/OPG, Runx2 and cathepsin K compared to day 0 (P < 0.0001). At 21 and 42 days, FGFR2 was also expressed on osteoblasts, fibroblasts and inside enlarged lacunae of cementocytes along with acute and chronic inflammatory cells (macrophages, plasma cells and neutrophils). At all periods and cells, FGFR2 expression was observed in the cell membrane and cytoplasm, but not in the nucleus. CONCLUSION: In mice, FGFR2 was not expressed in tissues surrounding healthy teeth but was expressed in apical periodontitis, specifically in the membrane and cytoplasm of osteoblasts, fibroblasts, lacunae of cementocytes, and acute and chronic inflammatory cells (macrophages, plasma cells and neutrophils). Its expression was correlated with the size of the periapical lesions.


Assuntos
Periodontite Periapical , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos , Animais , Cemento Dentário , Camundongos , Osteoclastos , Tratamento do Canal Radicular
12.
Molecules ; 24(16)2019 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-31395798

RESUMO

The micro sequential injection analysis / lab-on-valve (µSIA-LOV) system is a miniaturized SIA system resulting from the implementation of a lab-on-valve (LOV) atop of the selection valve. It integrates the detection cell and the sample processing channels into the same device, promoting the reduction of reagent consumption and waste generation, the improvement of the versatility, and the reduction of the time of analysis. All of these characteristics are really relevant to the implementation of enzymatic reactions. Additionally, the evaluation of cholesterol in serum samples is widely relevant in clinical diagnosis, since higher values of cholesterol in human blood are actually an important risk factor for cardiovascular problems. An automatic methodology was developed based on the µSIA-LOV system in order to evaluate its advantages in the implementation of enzymatic reactions performed by cholesterol esterase, cholesterol oxidase and peroxidase. Considering these reactions, the developed methodology was also used for the evaluation of cholesterol in human serum samples, showing reliable and accurate results. The developed methodology presented detection and quantification limits of 1.36 and 4.53 mg dL-1 and a linear range up to 40 mg dL-1. This work confirmed that this µSIA-LOV system is a simple, rapid, versatile, and robust analytical tool for the automatic implementation of enzymatic reactions performed by cholesterol esterase, cholesterol oxidase, and peroxidase. It is also a useful alternative methodology for the routine determinations of cholesterol in real samples, even when compared with other automatic methodologies.


Assuntos
Colesterol Oxidase/química , Colesterol/sangue , Dispositivos Lab-On-A-Chip , Peroxidase/química , Esterol Esterase/química , Humanos , Limite de Detecção
13.
Analyst ; 143(10): 2426-2434, 2018 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-29713696

RESUMO

An automatic assay was developed that is intended to be a generic tool for evaluation of a horseradish peroxidase activity in different ionic liquids (ILs). Ionic liquids with different characteristics were used and their effects on the enzymatic reaction, were compared with those obtained with conventional organic solvents. In addition, ILs were tested as solvents for the enzyme substrate (bisphenol A (BPA)). ILs were shown to be a good alternative to conventional organic solvents from either the effect on enzymatic activity or the solubilization of bisphenol. Since bisphenol A is an endocrine disruptor frequently used in plastic industries, it was also applied the developed enzymatic methodology for quantification of this compound in real beverage samples. To increase the sensitivity (already increased by the use of an IL) and the selectivity of the methodology, a sample pre-treatment using a molecular recognition solid phase extraction was applied. Finally, the methodology presented detection and quantification limits of 7.73 × 10-4 and 1.29 × 10-3 mmol L-1 and a linear range up to 1.00 mmol L-1, allowing accurate and reliable quantifications of bisphenol in beer and cola drink samples. This work confirmed the potential of a sequential injection analysis (SIA) system as a simple, versatile, robust, and rapid analytical tool for automating enzymatic assays in ILs medium and, at the same time, showed it to be a relevant automatic alternative for routine determinations of bisphenol A in food samples.


Assuntos
Compostos Benzidrílicos/análise , Biocatálise , Análise de Alimentos/métodos , Líquidos Iônicos/química , Fenóis/análise , Disruptores Endócrinos , Extração em Fase Sólida , Solventes
14.
Ecotoxicol Environ Saf ; 152: 55-60, 2018 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-29407782

RESUMO

Antipsychotic (AP) drugs are becoming accumulated in terrestrial and aqueous resources due to their actual consumption. Thus, the search of methods for assessing the contamination load of these drugs is mandatory. The COD is a key parameter used for monitoring water quality upon the assessment of the effect of polluting agents on the oxygen level. Thus, the present work aims to assess the chemical oxygen demand (COD) levels of several typical and atypical antipsychotic drugs in order to obtain structure-activity relationships. It was implemented the titrimetric method with potassium dichromate as oxidant and a digestion step of 2h, followed by the measurement of remained unreduced dichromate by titration. After that, an automated sequential injection analysis (SIA) method was, also, used aiming to overcome some drawbacks of the titrimetric method. The results obtained showed a relationship between the chemical structures of antipsychotic drugs and their COD values, where the presence of aromatic rings and oxidable groups give higher COD values. It was obtained a good compliance between the results of the reference batch procedure and the SIA system, and the APs were clustered in two groups, with the values ratio between the methodologies, of 2 or 4, in the case of lower or higher COD values, respectively. The SIA methodology is capable of operating as a screening method, in any stage of a synthetic process, being also more environmentally friendly, and cost-effective. Besides, the studies presented open promising perspectives for the improvement of the effectiveness of pharmaceutical removal from the waste effluents, by assessing COD values.


Assuntos
Antipsicóticos/análise , Análise da Demanda Biológica de Oxigênio/métodos , Águas Residuárias/análise , Poluentes Químicos da Água/análise , Antipsicóticos/química , Oxirredução , Oxigênio/análise , Relação Estrutura-Atividade , Titulometria , Eliminação de Resíduos Líquidos , Poluentes Químicos da Água/química , Qualidade da Água
15.
Chemphyschem ; 18(10): 1351-1357, 2017 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-28217924

RESUMO

A novel automated fluorimetric technique was developed for the assessment of the chemical oxygen demand (COD) of ionic liquids (ILs) and combined with a photodegradation step to promote IL degradation. The method was implemented on a sequential injection analysis (SIA) system and is based on the reduction of cerium(IV) in the presence of irradiated ILs. Compounds incorporating the chloride anion were found to exhibit higher COD values and 1-butyl-3-methylimidazolium chloride ([bmim]+ [Cl]- ), 1-butyl-1-methylpyrrolidinium chloride ([bmpyr]+ [Cl]- ), and1-hexyl-3-methylimidazolium chloride ([hmim]+ [Cl]- ) also exhibited considerable photodegradability, whereas the cholinium cation and methanesulfonate and tetrafluoroborate anions showed resistance to photolysis. The developed methodology proved to be a simple, affordable, and robust method, showing good repeatability under the tested conditions (rsd <3.5 %, n=10). Therefore, it is expected that the developed approach can be used as a screening method for the preliminary evaluation of compounds' potential impact in the aquatic field. Additionally, the photolysis step presents an attractive option to promote degradation of ILs prior to their release into wastewater.


Assuntos
Automação , Fluorometria , Líquidos Iônicos/química , Oxigênio/química , Processos Fotoquímicos
16.
J Appl Microbiol ; 121(3): 811-20, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27159339

RESUMO

AIM: The objective of this study was to identify and characterize lactic acid bacteria isolated from human milk, with an emphasis on their probiotic properties. METHODS AND RESULTS: The strains were tested for their ability to inhibit growth of Enterococcus faecalis, Salmonella enterica subsp. enterica serotype Enteritidis, Listeria monocytogenes, Staphylococcus aureus and Escherichia coli, as well as for susceptibility to antimicrobial agents and for acid pH and bile salt tolerance. Gram-positive and catalase-negative were selected and identified as Enterococcus (83·3%) after sequencing the 16S rDNA gene. All the isolates inhibited growth of Ent. faecalis and S. serotype Enteritidis, 97% inhibited growth of L. monocytogenes and Staph. aureus and 78·8% inhibited growth of E. coli. Most of the isolates were resistant to gentamicin (50%) and vancomycin (47%). Twelve isolates grew when subjected to pH 3·0 and 0·1% bile salts. At lower pH (2·5-2·0), Ent. faecalis F1 and Weissella confusa F8 were more efficient. CONCLUSION: It was possible to isolate from human milk the lactic acid bacteria with potential for use as probiotics. SIGNIFICANCE AND IMPACT OF THE STUDY: Lactic acid bacteria isolated of nursing mothers have probiotic properties.


Assuntos
Bactérias/isolamento & purificação , Leite Humano/microbiologia , Probióticos/isolamento & purificação , Bactérias/classificação , Bactérias/genética , Feminino , Humanos , Ácido Láctico/metabolismo , Probióticos/classificação , Probióticos/metabolismo
17.
Chemphyschem ; 16(9): 1880-8, 2015 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-25908390

RESUMO

Immobilization of quantum dots (QDs) onto solid supports could improve their applicability in the development of sensing platforms and solid-phase reactors by allowing the implementation of reusable surfaces and the execution of repetitive procedures. As the reactivity of QDs relies mostly on their surface chemistry, immobilization could also limit the disruption of solution stability that could prevent stable measurements. Herein, distinct strategies to immobilize QDs onto porous aminated supports, such as physical adsorption and the establishment of chemical linking, were evaluated. This work explores the influence of QD capping and size, concentration, pH, and contact time between the support and the QDs. Maximum QD retention was obtained for physical adsorption assays. Freundlich and Langmuir isotherms were used to analyze the equilibrium data. Gibbs free energy, enthalpy, and entropy were calculated and the stability of immobilized QDs was confirmed.

18.
ScientificWorldJournal ; 2015: 547569, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25874248

RESUMO

This study evaluated the effect of CO2 laser irradiation and topical fluoride therapy in the control of caries progression on primary teeth enamel. 30 fragments (3 × 3 × 2 mm) from primary canines were submitted to an initial cariogenic challenge that consisted of immersion on demineralizing solution for 3 hours and remineralizing solution for 21 hours for 5 days. Fragments were randomly assigned into three groups (n = 10): L: CO2 laser (λ = 10.6 µm), APF: 1.23% acidulated phosphate fluoride, and C: no treatment (control). CO2 laser was applied with 0.5 W power and 0.44 J/cm(2) energy density. Fluoride application was performed with 0.1 g for 1 minute. Cariogenic challenge was conducted for 5 days following protocol previously described. Subsurface Knoop microhardness was measured at 30 µm from the edge. Obtained data were subjected to analysis the variance (ANOVA) and Duncan test with significance of 5%. It was found that the L group showed greater control of deciduous enamel demineralization and were similar to those of APF group, while being statistically different from C group (P ≤ 0.05) that showed the lowest microhardness values. It was concluded that CO2 laser can be an additional resource in caries control progression on primary teeth enamel.


Assuntos
Cárie Dentária/patologia , Cárie Dentária/radioterapia , Esmalte Dentário/patologia , Fluoretos Tópicos/administração & dosagem , Lasers de Gás/uso terapêutico , Dente Decíduo/patologia , Esmalte Dentário/efeitos dos fármacos , Humanos , Desmineralização do Dente/patologia , Desmineralização do Dente/radioterapia , Dente Decíduo/efeitos dos fármacos
19.
Gene Ther ; 21(12): 1041-50, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25273354

RESUMO

Familial amyloidotic polyneuropathy (FAP) is a neurodegenerative disorder characterized by extracellular deposition of amyloid fibrils composed by mutated transthyretin (TTR) mainly in the peripheral nervous system. At present, liver transplantation is still the standard treatment to halt the progression of clinical symptoms in FAP, but new therapeutic strategies are emerging, including the use of TTR stabilizers. Here we propose to establish a new gene therapy approach using adeno-associated virus (AAV) vectors to deliver the trans-suppressor TTR T119M variant to the liver of transgenic TTR V30M mice at different ages. This TTR variant is known for its ability to stabilize the tetrameric protein. Analysis of the gastrointestinal tract of AAV-treated animals revealed a significant reduction in deposition of TTR non-fibrillar aggregates in as much as 34% in stomach and 30% in colon, as well as decreased levels of biomarkers associated with TTR deposition, namely the endoplasmic reticulum stress marker BiP and the extracellular matrix protein MMP-9. Moreover, we showed with different studies that our approach leads to an increase in tetrameric and more stable forms of TTR, in favor of destabilized monomers. Altogether our data suggest the possibility to use this gene therapy approach in a prophylactic manner to prevent FAP pathology.


Assuntos
Neuropatias Amiloides Familiares/terapia , Terapia Genética/métodos , Pré-Albumina/genética , Neuropatias Amiloides Familiares/genética , Animais , Dependovirus/genética , Modelos Animais de Doenças , Eletroforese em Gel Bidimensional , Estresse do Retículo Endoplasmático/genética , Proteínas da Matriz Extracelular/genética , Proteínas da Matriz Extracelular/metabolismo , Regulação da Expressão Gênica , Técnicas de Transferência de Genes , Marcadores Genéticos , Vetores Genéticos , Fígado/metabolismo , Metaloproteinase 9 da Matriz/genética , Metaloproteinase 9 da Matriz/metabolismo , Camundongos , Camundongos Transgênicos , Sistema Nervoso Periférico/metabolismo , Pré-Albumina/metabolismo , Proteômica
20.
Biosens Bioelectron ; 251: 116095, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38382268

RESUMO

Chronic wounds (CW) present a significant healthcare challenge due to their prolonged healing time and associated complications. To effectively treat these wounds and prevent further deterioration, monitoring their healing progress is crucial. Traditional wound assessment methods relying on visual inspection and subjective evaluation are prone to inter-observer variability. Biomarkers play a critical role in objectively evaluating wound status and predicting healing outcomes, providing quantitative measures of wound healing progress, inflammation, infection, and tissue regeneration. Recent attention has been devoted to identifying and validating CW biomarkers. Various studies have investigated potential biomarkers, including growth factors, cytokines, proteases, and extracellular matrix components, shedding light on the complex molecular and cellular processes within CW. This knowledge enables a more targeted and personalized approach to wound management. Accurate and sensitive techniques are necessary for detecting CW biomarkers. Thus, this review compares and discusses the use of electrochemical and optical sensors for biomarker determination. The advantages and disadvantages of these sensors are highlighted. Differences in detection capabilities and characteristics such as non-invasiveness, portability, high sensitivity, specificity, simplicity, cost-effectiveness, compatibility with point-of-care applications, and real-time monitoring of wound biomarkers will be pointed out and compared. In summary, this work provides an overview of CW, explores the emerging field of CW biomarkers, and discusses methods for detecting these biomarkers, with a specific focus on optical and electrochemical sensors. The potential of further research and development in this field for advancing wound care and improving patient outcomes will also be noted.


Assuntos
Técnicas Biossensoriais , Humanos , Biomarcadores/análise , Cicatrização , Atenção à Saúde
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