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1.
Crit Care Explor ; 6(5): e1089, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38728059

RESUMO

IMPORTANCE: Patients admitted with cerebral hemorrhage or cerebral edema often undergo external ventricular drain (EVD) placement to monitor and manage intracranial pressure (ICP). A strain gauge transducer accompanies the EVD to convert a pressure signal to an electrical waveform and assign a numeric value to the ICP. OBJECTIVES: This study explored ICP accuracy in the presence of blood and other viscous fluid contaminates in the transducer. DESIGN: Preclinical comparative design study. SETTING: Laboratory setting using two Natus EVDs, two strain gauge transducers, and a sealed pressure chamber. PARTICIPANTS: No human subjects or animal models were used. INTERVENTIONS: A control transducer primed with saline was compared with an investigational transducer primed with blood or with saline/glycerol mixtures in mass:mass ratios of 25%, 50%, 75%, and 100% glycerol. Volume in a sealed chamber was manipulated to reflect changes in ICP to explore the impact of contaminates on pressure measurement. MEASUREMENTS AND MAIN RESULTS: From 90 paired observations, ICP readings were statistically significantly different between the control (saline) and experimental (glycerol or blood) transducers. The time to a stable pressure reading was significantly different for saline vs. 25% glycerol (< 0.0005), 50% glycerol (< 0.005), 75% glycerol (< 0.0001), 100% glycerol (< 0.0005), and blood (< 0.0005). A difference in resting stable pressure was observed for saline vs. blood primed transducers (0.041). CONCLUSIONS AND RELEVANCE: There are statistically significant and clinically relevant differences in time to a stable pressure reading when contaminates are introduced into a closed drainage system. Changing a transducer based on the presence of blood contaminate should be considered to improve accuracy but must be weighed against the risk of introducing infection.


Assuntos
Pressão Intracraniana , Transdutores de Pressão , Pressão Intracraniana/fisiologia , Humanos , Sangue/metabolismo , Glicerol , Monitorização Fisiológica/instrumentação , Monitorização Fisiológica/métodos , Drenagem/instrumentação , Hemorragia Cerebral/fisiopatologia , Hemorragia Cerebral/diagnóstico
2.
Food Res Int ; 187: 114334, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38763634

RESUMO

Red-fleshed apple cultivars with an enhanced content of polyphenolic compounds have attracted increasing interest due to their promising health benefits. Here, we have analysed the polyphenolic content of young, red-fleshed apples (RFA) and optimised extraction conditions of phenolics by utilising natural deep eutectic solvents (NDES). We also compare the antioxidant, neuroprotective and antimicrobial activities of NDES- and methanol-extracted phenolics from young RFA. High-performance liquid chromatography coupled to high-resolution mass spectrometry (HPLC-HRMS) was used for phenolics identification and quantification. Besides young RFA, ripe red-fleshed, young and ripe white-fleshed apples were analysed, revealing that young RFA possess the highest phenolic content (2078.4 ± 4.0 mg gallic acid equivalent/100 g), and that ripe white-fleshed apples contain the least amount of phenolics (545.0 ± 32.0 mg gallic acid equivalent/100 g). The NDES choline chloride-glycerol containing 40 % w/w H2O gave similar yields at 40 °C as methanol. In addition, the polyphenolics profile, and bioactivities of the NDES extract from young RFA were comparable that of methanol extracts. Altogether, our data show that NDES extracts of young RFA are a promising source of bioactive polyphenolics with potential applications in diverse sectors, e.g., for functional food production, smart material engineering and natural therapies.


Assuntos
Antioxidantes , Solventes Eutéticos Profundos , Frutas , Malus , Polifenóis , Malus/química , Polifenóis/análise , Polifenóis/isolamento & purificação , Antioxidantes/análise , Antioxidantes/química , Cromatografia Líquida de Alta Pressão , Frutas/química , Solventes Eutéticos Profundos/química , Extratos Vegetais/química , Colina/química , Glicerol/química , Fármacos Neuroprotetores/isolamento & purificação , Fármacos Neuroprotetores/química , Espectrometria de Massas
3.
Proc Natl Acad Sci U S A ; 121(20): e2310771121, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38709917

RESUMO

Shifts in the hydrogen stable isotopic composition (2H/1H ratio) of lipids relative to water (lipid/water 2H-fractionation) at natural abundances reflect different sources of the central cellular reductant, NADPH, in bacteria. Here, we demonstrate that lipid/water 2H-fractionation (2εfattyacid/water) can also constrain the relative importance of key NADPH pathways in eukaryotes. We used the metabolically flexible yeast Saccharomyces cerevisiae, a microbial model for respiratory and fermentative metabolism in industry and medicine, to investigate 2εfattyacid/water. In chemostats, fatty acids from glycerol-respiring cells were >550‰ 2H-enriched compared to those from cells aerobically fermenting sugars via overflow metabolism, a hallmark feature in cancer. Faster growth decreased 2H/1H ratios, particularly in glycerol-respiring cells by 200‰. Variations in the activities and kinetic isotope effects among NADP+-reducing enzymes indicate cytosolic NADPH supply as the primary control on 2εfattyacid/water. Contributions of cytosolic isocitrate dehydrogenase (cIDH) to NAPDH production drive large 2H-enrichments with substrate metabolism (cIDH is absent during fermentation but contributes up to 20 percent NAPDH during respiration) and slower growth on glycerol (11 percent more NADPH from cIDH). Shifts in NADPH demand associated with cellular lipid abundance explain smaller 2εfattyacid/water variations (<30‰) with growth rate during fermentation. Consistent with these results, tests of murine liver cells had 2H-enriched lipids from slower-growing, healthy respiring cells relative to fast-growing, fermenting hepatocellular carcinoma. Our findings point to the broad potential of lipid 2H/1H ratios as a passive natural tracker of eukaryotic metabolism with applications to distinguish health and disease, complementing studies that rely on complex isotope-tracer addition methods.


Assuntos
Ácidos Graxos , Fermentação , NADP , Saccharomyces cerevisiae , Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/crescimento & desenvolvimento , Ácidos Graxos/metabolismo , NADP/metabolismo , Aerobiose , Deutério/metabolismo , Humanos , Glicerol/metabolismo , Isocitrato Desidrogenase/metabolismo
4.
Carbohydr Polym ; 337: 122165, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38710577

RESUMO

This research intended to remove residual protein from chitin with proteases in deep eutectic solvents (DESs). The activities of some proteases in several DESs, including choline chloride/p-toluenesulfonic acid, betaine/glycerol (Bet/G), choline chloride/malic acid, choline chloride/lactic acid, and choline chloride/urea, which are capable of dissolving chitin, were tested, and only in Bet/G some proteases were found to be active, with subtilisin A, ficin, and bromelain showing higher activity than other proteases. However, the latter two proteases caused degradation of chitin molecules. Further investigation revealed that subtilisin A in Bet/G did not exhibit "pH memory", which is a universal characteristic displayed by enzymes dispersed in organic phases, and the catalytic characteristics of subtilisin A in Bet/G differed significantly from those in aqueous phase. The conditions for protein removal from chitin by subtilisin A in Bet/G were determined: Chitin dissolved in Bet/G with 0.5 % subtilisin A (442.0 U/mg, based on the mass of chitin) was hydrolyzed at 45 °C for 30 min. The residual protein content in chitin decreased from 5.75 % ± 0.10 % to 1.01 % ± 0.12 %, improving protein removal by 57.20 % compared with protein removal obtained by Bet/G alone. The crystallinity and deacetylation degrees of chitin remained unchanged after the treatment.


Assuntos
Betaína , Quitina , Solventes Eutéticos Profundos , Glicerol , Quitina/química , Betaína/química , Glicerol/química , Solventes Eutéticos Profundos/química , Hidrólise , Subtilisina/metabolismo , Subtilisina/química , Concentração de Íons de Hidrogênio , Peptídeo Hidrolases/metabolismo , Peptídeo Hidrolases/química , Colina/química
5.
Prep Biochem Biotechnol ; 54(5): 709-719, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38692288

RESUMO

Identification of a single genetic target for microbial strain improvement is difficult due to the complexity of the genetic regulatory network. Hence, a more practical approach is to identify bottlenecks in the regulatory networks that control critical metabolic pathways. The present work focuses on enhancing cellular physiology by increasing the metabolic flux through the central carbon metabolic pathway. Global regulator cra (catabolite repressor activator), a DNA-binding transcriptional dual regulator was selected for the study as it controls the expression of a large number of operons that modulate central carbon metabolism. To upregulate the activity of central carbon metabolism, the cra gene was co-expressed using a plasmid-based system. Co-expression of cra led to a 17% increase in the production of model recombinant protein L-Asparaginase-II. A pulse addition of 0.36% of glycerol every two hours post-induction, further increased the production of L-Asparaginase-II by 35% as compared to the control strain expressing only recombinant protein. This work exemplifies that upregulating the activity of central carbon metabolism by tuning the expression of regulatory genes like cra can relieve the host from cellular stress and thereby promote the growth as well as expression of recombinant hosts.


Assuntos
Asparaginase , Escherichia coli , Proteínas Recombinantes , Asparaginase/genética , Asparaginase/metabolismo , Asparaginase/biossíntese , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Glicerol/metabolismo , Regulação Bacteriana da Expressão Gênica
6.
AMA J Ethics ; 26(4): E289-294, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38564743

RESUMO

This commentary responds to a case about diethylene glycol-contaminated glycerin in cough syrup. Glycerin is a commonly used excipient in medicines to improve texture and taste. Excipients are typically pharmacologically inactive ingredients contained in prescription and over-the-counter drugs that play a critical role in the delivery, effectiveness, and stability of active drug substances. The commentary first canvasses how contaminants enter the excipient supply chains. One way is by misleading labeling or intentional adulteration by manufacturers or suppliers. Another way is by human or systemic error. This commentary then discusses quality control testing and suggests the ethical and clinical importance of increased transparency in excipient supply chains.


Assuntos
Excipientes , Glicerol , Criança , Humanos , Excipientes/efeitos adversos , Preparações Farmacêuticas , Contaminação de Medicamentos , Tosse/tratamento farmacológico
7.
Water Environ Res ; 96(4): e11017, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38565318

RESUMO

This study explored the implementation of mainstream partial denitrification with anammox (PdNA) in the second anoxic zone of a wastewater treatment process in an integrated fixed film activated sludge (IFAS) configuration. A pilot study was conducted to compare the use of methanol and glycerol as external carbon sources for an IFAS PdNA startup, with a goal to optimize nitrogen removal while minimizing carbon usage. The study also investigated the establishment of anammox bacteria on virgin carriers in IFAS reactors without the use of seeding, and it is the first IFAS PdNA startup to use methanol as an external carbon source. The establishment of anammox bacteria was confirmed in both reactors 102 days after startup. Although the glycerol-fed reactor achieved a higher steady-state maximum ammonia removal rate because of anammox bacteria (1.6 ± 0.3 g/m2/day) in comparison with the methanol-fed reactor (1.2 ± 0.2 g/m2/day), both the glycerol- and methanol-fed reactors achieved similar average in situ ammonia removal rates of 0.39 ± 0.2 g/m2/day and 0.40 ± 0.2 g/m2/day, respectively. Additionally, when the upstream ammonia versus NOx (AvN) control system maintained an ideal ratio of 0.40-0.50 g/g, the methanol-fed reactor attained a lower average effluent TIN concentration (3.50 ± 1.2 mg/L) than the glycerol-fed reactor (4.43 ± 1.6 mg/L), which was prone to elevated nitrite concentrations in the effluent. Overall, this research highlights the potential for PdNA in IFAS configurations as an efficient and cost-saving method for wastewater treatment, with methanol as a viable carbon source for the establishment of anammox bacteria. PRACTITIONER POINTS: Methanol is an effective external carbon source for an anammox startup that avoids the need for costly alternative carbon sources. The methanol-fed reactor demonstrated higher TIN removal compared with the glycerol-fed reactor because of less overproduction of nitrite. Anammox bacteria was established in an IFAS reactor without seeding and used internally stored carbon to reduce external carbon addition. Controlling the influent ammonia versus NOx (AvN) ratio between 0.40 and 0.50 g/g allowed for low and stable TIN effluent conditions.


Assuntos
Compostos de Amônio , Esgotos , Esgotos/microbiologia , Amônia , Desnitrificação , Metanol , Glicerol , Nitritos , Projetos Piloto , Oxidação Anaeróbia da Amônia , Reatores Biológicos/microbiologia , Bactérias , Nitrogênio , Oxirredução
8.
Cells ; 13(7)2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38607011

RESUMO

Calcitonin gene-related peptide (CGRP) and nitric oxide (NO) have been recognized as important mediators in migraine but their mechanisms of action and interaction have not been fully elucidated. Monoclonal anti-CGRP antibodies like fremanezumab are successful preventives of frequent migraine and can be used to study CGRP actions in preclinical experiments. Fremanezumab (30 mg/kg) or an isotype control monoclonal antibody was subcutaneously injected to Wistar rats of both sexes. One to several days later, glyceroltrinitrate (GTN, 5 mg/kg) mimicking nitric oxide (NO) was intraperitoneally injected, either once or for three consecutive days. The trigeminal ganglia were removed to determine the concentration of CGRP using an enzyme-linked immunosorbent assay (ELISA). In one series of experiments, the animals were trained to reach an attractive sugar solution, the access to which could be limited by mechanical or thermal barriers. Using a semi-automated registration system, the frequency of approaches to the source, the residence time at the source, and the consumed solution were registered. The results were compared with previous data of rats not treated with GTN. The CGRP concentration in the trigeminal ganglia was generally higher in male rats and tended to be increased in animals treated once with GTN, whereas the CGRP concentration decreased after repetitive GTN treatment. No significant difference in CGRP concentration was observed between animals having received fremanezumab or the control antibody. Animals treated with GTN generally spent less time at the source and consumed less sugar solution. Without barriers, there was no significant difference between animals having received fremanezumab or the control antibody. Under mechanical barrier conditions, all behavioral parameters tended to be reduced but animals that had received fremanezumab tended to be more active, partly compensating for the depressive effect of GTN. In conclusion, GTN treatment seems to increase the production of CGRP in the trigeminal ganglion independently of the antibodies applied, but repetitive GTN administration may deplete CGRP stores. GTN treatment generally tends to suppress the animals' activity and increase facial sensitivity, which is partly compensated by fremanezumab through reduced CGRP signaling. If CGRP and NO signaling share the same pathway in sensitizing trigeminal afferents, GTN and NO may act downstream of CGRP to increase facial sensitivity.


Assuntos
Peptídeo Relacionado com Gene de Calcitonina , Transtornos de Enxaqueca , Feminino , Ratos , Masculino , Animais , Peptídeo Relacionado com Gene de Calcitonina/metabolismo , Glicerol , Ratos Wistar , Roedores/metabolismo , Óxido Nítrico , Nociceptividade , Nitroglicerina/farmacologia , Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais/uso terapêutico , Transtornos de Enxaqueca/tratamento farmacológico , Transtornos de Enxaqueca/metabolismo , Açúcares
9.
Appl Microbiol Biotechnol ; 108(1): 297, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38607564

RESUMO

Glycosidic osmolytes are widespread natural compounds that protect microorganisms and their macromolecules from the deleterious effects of various environmental stresses. Their protective properties have attracted considerable interest for industrial applications, especially as active ingredients in cosmetics and healthcare products. In that regard, the osmolyte glucosylglycerate is somewhat overlooked. Glucosylglycerate is typically accumulated by certain organisms when they are exposed to high salinity and nitrogen starvation, and its potent stabilizing effects have been demonstrated in vitro. However, the applications of this osmolyte have not been thoroughly explored due to the lack of a cost-efficient production process. Here, we present an overview of the progress that has been made in developing promising strategies for the synthesis of glucosylglycerate and its precursor glycerate, and discuss the remaining challenges. KEY POINTS: • Bacterial milking could be explored for fermentative production of glucosylglycerate • Glycoside phosphorylases of GH13_18 represent attractive alternatives for biocatalytic production • Conversion of glycerol with alditol oxidase is a promising strategy for generating the precursor glycerate.


Assuntos
Glicosídeos , Compostos Orgânicos , Biocatálise , Fermentação , Glicerol
10.
Molecules ; 29(7)2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38611912

RESUMO

This report demonstrates the first asymmetric synthesis of enantiopure structured triacylglycerols (TAGs) of the ABC type presenting three non-identical fatty acids, two of which are unsaturated. The unsaturated fatty acids included monounsaturated oleic acid (C18:1 n-9) and polyunsaturated linoleic acid (C18:2 n-6). This was accomplished by a six-step chemoenzymatic approach starting from (R)- and (S)-solketals. The highly regioselective immobilized Candida antarctica lipase (CAL-B) played a crucial role in the regiocontrol of the synthesis. The synthesis also benefited from the use of the p-methoxybenzyl (PMB) ether protective group, which enabled the incorporation of two different unsaturated fatty acids into the glycerol skeleton. The total of six such TAGs were prepared, four constituting the unsaturated fatty acids in the sn-1 and sn-2 positions, with a saturated fatty acid in the remaining sn-3 position of the glycerol backbone. In the two remaining TAGs, the different unsaturated fatty acids accommodated the sn-1 and sn-3 end positions, with the saturated fatty acid present in the sn-2 position. Enantiopure TAGs are urgently demanded as standards for the enantiospecific analysis of intact TAGs in fats and oils.


Assuntos
Ácidos Graxos , Glicerol , Éteres , Ácido Linoleico , Triglicerídeos
11.
Int J Mol Sci ; 25(7)2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38612541

RESUMO

Glycerol-3-phosphate acyltransferase (GPAT) catalyzes the first step in triacylglycerol synthesis. Understanding its substrate recognition mechanism may help to design drugs to regulate the production of glycerol lipids in cells. In this work, we investigate how the native substrate, glycerol-3-phosphate (G3P), and palmitoyl-coenzyme A (CoA) bind to the human GPAT isoform GPAT4 via molecular dynamics simulations (MD). As no experimentally resolved GPAT4 structure is available, the AlphaFold model is employed to construct the GPAT4-substrate complex model. Using another isoform, GPAT1, we demonstrate that once the ligand binding is properly addressed, the AlphaFold complex model can deliver similar results to the experimentally resolved structure in MD simulations. Following the validated protocol of complex construction, we perform MD simulations using the GPAT4-substrate complex. Our simulations reveal that R427 is an important residue in recognizing G3P via a stable salt bridge, but its motion can bring the ligand to different binding hotspots on GPAT4. Such high flexibility can be attributed to the flexible region that exists only on GPAT4 and not on GPAT1. Our study reveals the substrate recognition mechanism of GPAT4 and hence paves the way towards designing GPAT4 inhibitors.


Assuntos
Glicerol , Glicerofosfatos , Simulação de Dinâmica Molecular , Humanos , Ligantes , Glicerol-3-Fosfato O-Aciltransferase , Isoformas de Proteínas , Fosfatos
12.
Food Microbiol ; 121: 104513, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38637075

RESUMO

Saccharomyces cerevisiae is a major actor in winemaking that converts sugars from the grape must into ethanol and CO2 with outstanding efficiency. Primary metabolites produced during fermentation have a great importance in wine. While ethanol content contributes to the overall profile, other metabolites like glycerol, succinate, acetate or lactate also have significant impacts, even when present in lower concentrations. S. cerevisiae is known for its great genetic diversity that is related to its natural or technological environment. However, the variation range of metabolic diversity which can be exploited to enhance wine quality depends on the pathway considered. Our experiment assessed the diversity of primary metabolites production in a set of 51 S. cerevisiae strains from various genetic backgrounds. Results pointed out great yield differences depending on the metabolite considered, with ethanol having the lowest variation. A negative correlation between ethanol and glycerol was observed, confirming glycerol synthesis as a suitable lever to reduce ethanol yield. Genetic groups were linked to specific yields, such as the wine group and high α-ketoglutarate and low acetate yields. This research highlights the potential of using natural yeast diversity in winemaking. It also provides a detailed data set on production of well known (ethanol, glycerol, acetate) or little-known (lactate) primary metabolites.


Assuntos
Saccharomyces cerevisiae , Vinho , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Vinho/análise , Fermentação , Glicerol/metabolismo , Carbono/metabolismo , Etanol/metabolismo , Acetatos/metabolismo , Lactatos
13.
AAPS PharmSciTech ; 25(5): 89, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38641711

RESUMO

Oral candidiasis is a fungal infection affecting the oral mucous membrane, and this research specifically addresses on a localized treatment through fluconazole-loaded ibuprofen in situ gel-based oral spray. The low solubility of ibuprofen is advantageous for forming a gel when exposed to an aqueous phase. The 1% w/w fluconazole-loaded in situ gel oral sprays were developed utilizing various concentrations of ibuprofen in N-methyl pyrrolidone. The prepared solutions underwent evaluation for viscosity, surface tension, contact angle, water tolerance, gel formation, interface interaction, drug permeation, and antimicrobial studies. The higher amount of ibuprofen reduced the surface tension and retarded solvent exchange. The use of 50% ibuprofen as a gelling agent demonstrated prolonged drug permeation for up to 24 h. The incorporation of Cremophor EL in the formulations resulted in increased drug permeation and exhibited effective inhibition against Candida albicans, Candida krusei, Candida lusitaniae, and Candida tropicalis. While the Cremophor EL-loaded formulation did not exhibit enhanced antifungal effects on agar media, its ability to facilitate the permeation of fluconazole and ibuprofen suggested potential efficacy in countering Candida invasion in the oral mucosa. Moreover, these formulations demonstrated significant thermal inhibition of protein denaturation in egg albumin, indicating anti-inflammatory properties. Consequently, the fluconazole-loaded ibuprofen in situ gel-based oral spray presents itself as a promising dosage form for oropharyngeal candidiasis treatment.


Assuntos
Candidíase Bucal , Fluconazol , Glicerol/análogos & derivados , Fluconazol/farmacologia , Candidíase Bucal/tratamento farmacológico , Candidíase Bucal/microbiologia , Sprays Orais , Ibuprofeno/farmacologia , Antifúngicos , Candida albicans , Testes de Sensibilidade Microbiana
14.
FEMS Yeast Res ; 242024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38587863

RESUMO

Previously, we reported an engineered Saccharomyces cerevisiae CEN.PK113-1A derivative able to produce succinic acid (SA) from glycerol with net CO2 fixation. Apart from an engineered glycerol utilization pathway that generates NADH, the strain was equipped with the NADH-dependent reductive branch of the TCA cycle (rTCA) and a heterologous SA exporter. However, the results indicated that a significant amount of carbon still entered the CO2-releasing oxidative TCA cycle. The current study aimed to tune down the flux through the oxidative TCA cycle by targeting the mitochondrial uptake of pyruvate and cytosolic intermediates of the rTCA pathway, as well as the succinate dehydrogenase complex. Thus, we tested the effects of deletions of MPC1, MPC3, OAC1, DIC1, SFC1, and SDH1 on SA production. The highest improvement was achieved by the combined deletion of MPC3 and SDH1. The respective strain produced up to 45.5 g/L of SA, reached a maximum SA yield of 0.66 gSA/gglycerol, and accumulated the lowest amounts of byproducts when cultivated in shake-flasks. Based on the obtained data, we consider a further reduction of mitochondrial import of pyruvate and rTCA intermediates highly attractive. Moreover, the approaches presented in the current study might also be valuable for improving SA production when sugars (instead of glycerol) are the source of carbon.


Assuntos
Saccharomyces cerevisiae , Ácido Succínico , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Ácido Succínico/metabolismo , Glicerol/metabolismo , Dióxido de Carbono/metabolismo , NAD/metabolismo , Ácido Pirúvico/metabolismo , Membranas Mitocondriais/metabolismo , Carbono/metabolismo , Engenharia Metabólica/métodos
15.
J Int Soc Sports Nutr ; 21(1): 2346563, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38676933

RESUMO

BACKGROUND: Due to the increase in global temperature, it is necessary to investigate solutions so that athletes competing in hot conditions can perform in optimal conditions avoiding loss of performance and health problems. Therefore, this study aims to evaluate the effect of pre-exercise glycerol supplementation during a rectangular test at ambient temperature mid (28.2ºC) on dehydration variables in international race walkers. METHODS: Eight international male race walkers (age: 28.0 years (4.4); weight: 65.6 kg (6.6); height: 180.0 cm (5.0); fat mass: 6.72% (0.66); muscle mass: 33.3 kg (3.3); VO2MAX: 66.5 ml · kg-1·min-1 (1.9)) completed this randomized crossover design clinical trial. Subjects underwent two interventions: they consumed placebo (n = 8) and glycerol (n = 8) acutely, before a rectangular test where dehydration, RPE, metabolic, kinematic, and thermographic variables were analyzed before, during and after the test. RESULTS: After the intervention, significant differences were found between groups in body mass in favor of the placebo (Placebo: -2.23 kg vs Glycerol: -2.48 kg; p = 0.033). For other variables, no significant differences were found. CONCLUSION: Therefore, pre-exercise glycerol supplementation was not able to improve any dehydration, metabolic, kinematic, or thermographic variables during a rectangular test at temperature mid in international race walkers. Possibly, a higher environmental temperature could have generated a higher metabolic and thermoregulatory stress, generating differences between groups like other previous scientific evidence.


Assuntos
Estudos Cross-Over , Desidratação , Suplementos Nutricionais , Glicerol , Caminhada , Humanos , Masculino , Glicerol/administração & dosagem , Glicerol/sangue , Adulto , Caminhada/fisiologia , Fenômenos Biomecânicos , Termografia , Fenômenos Fisiológicos da Nutrição Esportiva , Adulto Jovem , Consumo de Oxigênio/efeitos dos fármacos , Temperatura Alta , Desempenho Atlético/fisiologia
16.
Food Chem Toxicol ; 188: 114668, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38641044

RESUMO

The safety of propylene glycol (PG) and vegetable glycerin (VG) as solvents in electronic cigarette liquid has received increasing attention and discussion. However, the conclusions derived from toxicity assessments conducted through animal experiments and traditional in vitro methodologies have consistently been contentious. This study constructed an original real-time aerosol exposure system, centered around a self-designed microfluidic bionic-lung chip, to assess the biological effects following exposure to aerosols from different solvents (PG, PG/VG mixture alone and PG/VG mixture in combination with nicotine) on BEAS-2B cells. The study aimed to investigate the impact of aerosols from different solvents on gene expression profiles, intracellular biomarkers (i.e., reactive oxygen species content, nitric oxide content, and caspase-3/7 activity), and extracellular biomarkers (i.e., IL-6, IL-8, TNF-α, and malondialdehyde) of BEAS-2B cells on-chip. Transcriptome analyses suggest that ribosomal function could serve as a potential target for the impact of aerosols derived from various solvents on the biological responses of BEAS-2B cells on-chip. And the results showed that aerosols of PG/VG mixtures had significantly less effect on intracellular and extracellular biomarkers in BEAS-2B cells than aerosols of PG, whereas increasing nicotine levels might elevate these effects of aerosol from PG/VG mixture.


Assuntos
Aerossóis , Sistemas Eletrônicos de Liberação de Nicotina , Solventes , Humanos , Solventes/toxicidade , Solventes/química , Linhagem Celular , Propilenoglicol/toxicidade , Glicerol/toxicidade , Glicerol/química , Dispositivos Lab-On-A-Chip , Espécies Reativas de Oxigênio/metabolismo , Nicotina/toxicidade , Biomarcadores/metabolismo
17.
J Colloid Interface Sci ; 667: 624-639, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38663278

RESUMO

Quick scarless healing remains a key issue for diabetic wounds. Here, a stretchable elastomeric hydrogel dressing composed of hydroxyethylcellulose (HEC), silk nano fiber-magnesium ion complex (Mg2+-SNF) and glycerol (Gly) was developed to optimize mechanical niche, anti-inflammatory and angiogenic behavior simultaneously. The composite hydrogel dressing exhibited skin-like elasticity (175.1 ± 23.9 %) and modulus (156.7 ± 2.5 KPa) while Mg2+-SNF complex endowed the dressing with angiogenesis, both favoring quick scarless skin regeneration. In vitro cell studies revealed that the hydrogel dressing stimulated fibroblast proliferation, endothelial cell migration and vessel-like tube formation, and also induced anti-inflammatory behavior of macrophages. In vivo results revealed accelerated healing of diabetic wounds. The improved granulation ingrowth and collagen deposition suggested high quality repair. Both thinner epidermal layer and low collagen I/III ratio of the regenerated skin confirmed scarless tissue formation. This bioactive hydrogel dressing has promising potential to address the multifaceted challenges of diabetic wound management.


Assuntos
Glicerol , Magnésio , Cicatrização , Cicatrização/efeitos dos fármacos , Animais , Glicerol/química , Glicerol/farmacologia , Magnésio/química , Magnésio/farmacologia , Camundongos , Seda/química , Hidrogéis/química , Hidrogéis/farmacologia , Materiais Biomiméticos/química , Materiais Biomiméticos/farmacologia , Diabetes Mellitus Experimental/tratamento farmacológico , Bandagens , Humanos , Ratos , Nanofibras/química , Proliferação de Células/efeitos dos fármacos , Neovascularização Fisiológica/efeitos dos fármacos , Masculino , Células Endoteliais da Veia Umbilical Humana , Celulose/química , Celulose/farmacologia , Celulose/análogos & derivados
18.
Bioresour Technol ; 401: 130734, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38670288

RESUMO

Currently, the predominant method for the industrial production of 1,3-dihydroxyacetone (DHA) from glycerol involves fed-batch fermentation. However, previous research has revealed that in the biocatalytic synthesis of DHA from glycerol, when the DHA concentration exceeded 50 g·L-1, it significantly inhibited microbial growth and metabolism, posing a challenge in maintaining prolonged and efficient catalytic production of DHA. In this study, a new integrated continuous production and synchronous separation (ICSS) system was constructed using hollow fiber columns and perfusion culture technology. Additionally, a cell reactivation technique was implemented to extend the biocatalytic ability of cells. Compared with fed-batch fermentation, the ICSS system operated for 360 h, yielding a total DHA of 1237.8 ± 15.8 g. The glycerol conversion rate reached 97.7 %, with a productivity of 3.44 g·L-1·h-1, representing 485.0 % increase in DHA production. ICSS system exhibited strong operational characteristics and excellent performance, indicating significant potential for applications in industrial bioprocesses.


Assuntos
Reatores Biológicos , Células Imobilizadas , Di-Hidroxiacetona , Glicerol , Di-Hidroxiacetona/metabolismo , Células Imobilizadas/metabolismo , Glicerol/metabolismo , Fermentação , Técnicas de Cultura Celular por Lotes/métodos , Perfusão , Catálise , Biocatálise
19.
Int J Biol Macromol ; 268(Pt 1): 131603, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38626835

RESUMO

The thermoplastic starch with glycerol is easy to retrograde and sensitive to hygroscopicity. In this study, branched 1,4-butanediol citrate oligomers with different molecular weights (P1, P2, and P3) are synthesized, and then mixed with glycerol (G) as the co-plasticizers to prepare thermoplastic starch (CS/PG). The results show that the molecular weight and branching degree of the branched 1,4-butanediol citrate oligomers increase as reaction time prolongs. Compared with glycerol plasticized starch, the thermoplastic starch films with branched 1,4-butanediol citrate oligomers/glycerol (10 wt%/20 wt%) have a better toughness, transmittance, and aging resistance, and have a lower crystallinity, hygroscopicity, and thermal stability. The toughness, transmittance, and aging resistance of CS/PG films are positively correlated with the molecular weight of the branched 1,4-butanediol citrate oligomers. These are due to the fact that the branched 1,4-butanediol citrate oligomer with a high molecular weight could form a stronger hydrogen bond and the more stable cross-linked structure with starch chains than that with a lower molecular weight. The elongation at break of CS/P3G film stored for 3 and 30 d are 98.0 % and 88.1 %, respectively. The mixture of branched butanediol citrate oligomers and glycerol, especially P3/G, has a potential application in the preparation of thermoplastic starch.


Assuntos
Butileno Glicóis , Glicerol , Peso Molecular , Plastificantes , Amido , Amido/química , Glicerol/química , Butileno Glicóis/química , Plastificantes/química , Temperatura , Citratos/química , Plásticos/química
20.
Chemosphere ; 358: 142060, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38648981

RESUMO

The widespread application of engineered nanoparticles (NPs) in environmental remediation has raised public concerns about their toxicity to aquatic organisms. Although appropriate surface modification can mitigate the ecotoxicity of NPs, the lack of polymer coating to inhibit toxicity completely and the insufficient knowledge about charge effect hinder the development of safe nanomaterials. Herein, we explored the potential of polyglycerol (PG) functionalization in alleviating the environmental risks of NPs. Iron oxide NPs (ION) of 20, 100, and 200 nm sizes (IONS, IONM and IONL, respectively) were grafted with PG to afford ION-PG. We examined the interaction of ION and ION-PG with Caenorhabditis elegans (C. elegans) and found that PG suppressed non-specific interaction of ION with C. elegans to reduce their accumulation and to inhibit their translocation. Particularly, IONS-PG was completely excluded from worms of all developmental stages. By covalently introducing sulfate, carboxyl and amino groups onto IONS-PG, we further demonstrated that positively charged IONS-PG-NH3+ induced high intestinal accumulation, cuticle adhesion and distal translocation, whereas the negatively charged IONS-PG-OSO3- and IONS-PG-COO- were excreted out. Consequently, no apparent deleterious effects on brood size and life span were observed in worms treated by IONS-PG and IONS-PG bearing negatively charged groups. This study presents new surface functionalization approaches for developing ecofriendly nanomaterials.


Assuntos
Caenorhabditis elegans , Glicerol , Polímeros , Caenorhabditis elegans/efeitos dos fármacos , Animais , Glicerol/química , Glicerol/toxicidade , Polímeros/química , Nanopartículas Magnéticas de Óxido de Ferro/química , Nanopartículas Magnéticas de Óxido de Ferro/toxicidade , Tamanho da Partícula , Propriedades de Superfície
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