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1.
Bioresour Technol ; 308: 123266, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32251855

RESUMO

Lactic acid (LA) fermentation was conducted with suspended and immobilized cells of an isolated Lactobacillus plantarum 23 strain using various fermentation strategies. Glucose and an alternative, relatively inexpensive carbon source - the hydrolysate of microalga Chlorella vulgaris ESP-31, were used as the carbon source. Batch fermentation using immobilized cells of L. plantarum 23 could enhance LA titer and yield by 43% and 39%, respectively, when compared with the suspended culture. Fed-batch culture integrated with in situ LA removal via ion exchange raised LA productivity by 72% by overcoming product inhibition. The highest LA productivity from glucose with PVA immobilized cells was 14.22 g/L/h, achieved under continuous operation at 50% w/v loading of immobilized beads and hydraulic retention time (HRT) of 2 h. PVA immobilized L. plantarum 23 could also use microalgal hydrolysate as the renewable carbon source, and the highest LA productivity was 9.93 g/L/h under continuous fermentation at 4 h HRT.


Assuntos
Chlorella vulgaris , Lactobacillus plantarum , Microalgas , Fermentação , Ácido Láctico , Álcool de Polivinil
2.
Bioresour Technol ; 307: 123194, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32234590

RESUMO

The use of acetate as carbon feedstock can enhance sustainability and economics of the current bio-productions. This study explored the potential of acetate for the production of 3-hydroxypropionic acid by engineered Pseudomonas denitrificans. Heterologous mcr (encoding malonyl-CoA reductase) from Chloroflexus aurantiacus and endogenous accABCD (encoding acetyl-CoA carboxylase) were overexpressed in P. denitrificans. Carbon flux to 3-HP synthesis at the malonyl-CoA node was promoted by suppressing fatty acid synthesis through addition of cerulenin or deletion of fabF gene. In addition, stimulation of glyoxylate shunt and/or TCA cycle were attempted. Recombinant P. denitrificans overexpressing mcr and accABCD produced 19.3 mM 3-HP with cerulenin addition, and 14.2 mM with fabF deletion, respectively. Furthermore, the non-growing cells devoid of fabF could continuously produce 3-HP up to 40.4 mM without losing its production activity for 22 h. This study demonstrates that acetate is a good substrate for 3-HP production by recombinant P. denitrificans.


Assuntos
Ácido Láctico , Pseudomonas , Acetatos , Ácido Láctico/análogos & derivados , Malonil Coenzima A
3.
Int J Syst Evol Microbiol ; 70(3): 1585-1590, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32228772

RESUMO

A novel lactic acid bacterium, strain MB7T, was isolated from lychee in Taiwan. MB7T is Gram-staining-positive, catalase-negative, non-motile, non-haemolytic, facultatively anaerobic, coccoid-shaped, heterofermentative and mainly produces d-lactic acid from glucose. Comparative analysis of 16S rRNA, pheS and rpoA gene sequences has demonstrated that the novel strain represented a member of the genus Leuconostoc. 16S rRNA gene sequencing results indicated that MB7T had the same sequence similarity of 99.25 % to four type strains of members of the genus Leuconostoc: Leuconostoc mesenteroides subsp. dextranicum DSM 20484T, Leuconostoc mesenteroides subsp. jonggajibkimchii DRC 1506T, Leuconostoc mesenteroides subsp. mesenteroides ATCC 8293T and Leuconostoc suionicum DSM 20241T. Additionally, high 16S rRNA sequence similarities were also observed with Leuconostoc mesenteroides subsp. cremoris ATCC 19254T (99.12 %) and Leuconostoc pseudomesenteroides NRIC 1777T (98.69 %). When comparing the genomes of these type strains, the average nucleotide identity values and digital DNA-DNA hybridization values of MB7T with these type strains were 76.57-80.53 and 22.0-22.6 %, respectively. MB7T also showed different phenotypic characteristics to other most closely related species of the genus Leuconostoc, such as carbohydrate metabolizing ability, halotolerance and growth at various pHs. On the basis of phenotypic and genotypic properties, strain MB7T represents a novel species belonging to the genus Leuconostoc, for which the name Leuconostoc litchii sp. nov. is proposed. The type strain is MB7T (=BCRC 81077T=NBRC 113542T).


Assuntos
Frutas/microbiologia , Leuconostoc/classificação , Litchi/microbiologia , Filogenia , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Fermentação , Ácido Láctico , Leuconostoc/isolamento & purificação , Leuconostoc mesenteroides , Hibridização de Ácido Nucleico , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Taiwan
4.
Waste Manag ; 107: 235-243, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32325410

RESUMO

The expansion of urban green areas has boosted the accumulation of gardening lignocellulosic residues that could be potentially used to produce platform chemicals like lactic acid. However, when using lignocelluloses, pretreatment step, such as steam explosion, is often needed to favour sugar release. Considering that the conversion of glucose from cellulose has been widely addressed, this work is focused on the valorisation of the steam-exploded gardening liquid fraction rich in hemicellulosic sugars. Since oligomeric sugars are usually solubilized during steam explosion, an enzymatic hydrolysis step was required in some cases to increase the monosaccharides content. Although the presence of inhibitors released during pretreatment (e.g. formic acid) hindered hydrolysis yields, the addition of hemicellulases and the enzyme dosage optimization resulted in 85%, 89% and 95% of glucose, xylose and arabinose release from soluble oligomers, respectively. Lactobacillus pentosus CECT4023T was used for lactic acid fermentation of C6 and C5 sugars from the hydrolysate with the highest sugars concentration, that did not require enzymatic hydrolysis. Xylose consumption was hampered due to the inhibitory effect of acids that produced pH drop. Different pH control systems were applied and automatic NaOH addition in bioreactor resulted in 21 g L-1 of lactic acid (95% of the maximum theoretical yield) that implied 44% increase in lactic acid production when compared with flask fermentation. These results provide new insights for the valorisation of emerging lignocellulosic materials like gardening residues into high added-value products.


Assuntos
Ácido Láctico , Vapor , Fermentação , Jardinagem , Concentração de Íons de Hidrogênio , Hidrólise , Xilose
5.
J Biomed Nanotechnol ; 16(2): 201-211, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32252881

RESUMO

A key issue in dendritic cell (DC)-based cancer immunotherapy is the effective delivery of tumor-specific antigens to DCs. To deliver antigens, non-viral vaccine system has been used in ex vivo manipulation. However, ex vivo manipulation is time-consuming, lacks quality control of DCs, and demonstrates low antigen delivery efficiency, which implicates that there are serious problems in therapeutic DC preparations. Therefore, we developed mannose (MN)-labeled poly(d, l-lactide-co-glycolide) (PLGA) nanoparticles (MN-PLGA-NPs) encapsulating tumor-specific antigens for targeted delivery to mannose receptors (MN-R) on DC surfaces without ex vivo manipulation. The MN-PLGA-NPs showed DC-selective delivery in tumor-bearing mice, leading to highly mature and activated DCs, which migrated to lymphoid organs, resulting in activation of cytotoxic CD8+ T cells. Additionally, MN-PLGA-NPs showed significant therapeutic efficacy in EG7 lymphoma tumorbearing mice. Our nano-platform technology can be used as a vaccine system to bypass ex vivo manipulation and enhance targeted delivery of tumor-specific antigens to DCs, which is well-suited for cancer immunotherapy.


Assuntos
Células Dendríticas , Nanopartículas , Neoplasias , Animais , Dioxanos , Imunoterapia , Ácido Láctico , Manose , Camundongos , Camundongos Endogâmicos C57BL , Neoplasias/terapia , Ácido Poliglicólico , Copolímero de Ácido Poliláctico e Ácido Poliglicólico
6.
Anticancer Res ; 40(4): 1989-1996, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32234888

RESUMO

BACKGROUND/AIM: The antitumor effect of sustained calcium supply on Src degradation was investigated in the context of hormone-dependent breast cancer, followed by elucidation of the underlying mechanisms. MATERIALS AND METHODS: Hormone-dependent T-47D breast cancer cells were used. Lactate calcium salt (LCS) was used as the source of sustained calcium supply, and the applicable concentration of LCS was determined by the colorimetric MTT assay. LCS-mediated deactivation of downstream signaling via Src degradation was identified by western blot and immunocytochemistry. RESULTS: Calcium-mediated degradation of Src decreased survival signaling via phosphoinositide 3-kinase and protein kinase B and resulted in significant inhibition of the clonogenic ability of hormone-dependent breast cancer cells. Tumor volume was significantly decreased in response to LCS injection in a heterotopic xenograft model, and immuno histochemistry revealed tumor necrosis. CONCLUSION: Sustained supply of calcium inhibited survival signaling via degradation of Src in hormone-dependent breast cancer cells.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Neoplasias Hormônio-Dependentes/tratamento farmacológico , Proteólise/efeitos dos fármacos , Quinases da Família src/genética , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Cálcio/farmacologia , Linhagem Celular Tumoral , Feminino , Humanos , Ácido Láctico/farmacologia , Neoplasias Hormônio-Dependentes/genética , Neoplasias Hormônio-Dependentes/patologia , Proteína Oncogênica v-akt/genética , Fosfatidilinositol 3-Quinases/genética , Transdução de Sinais/efeitos dos fármacos , Quinases da Família src/antagonistas & inibidores
7.
Anticancer Res ; 40(4): 1833-1841, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32234871

RESUMO

BACKGROUND/AIM: Time-restricted feeding (TRF) during the dark phase of the day restores metabolic homeostasis in mice. MATERIALS AND METHODS: We performed untargeted metabolomic analysis on plasma from mice subjected to TRF that attenuates high-fat diet-enhanced spontaneous metastasis of Lewis lung carcinoma (LLC). RESULTS: Twenty-four of 152 identified metabolites differed among the four dietary groups (non-LLC-bearing mice fed the AIN93G diet and LLC-bearing mice fed the AIN93G, the high-fat diet (HFD), or TRF of the HFD). Component 1 of sparse partial least squares-discriminant analysis showed a clear separation between non-LLC-bearing and LLC-bearing mice. Major metabolites responsible for the changes were elevations in α-tocopherol, docosahexaenoic acid, cholesterol, dihydrocholestrol, isoleucine, leucine, and phenylalanine and decreases in lactic acid and pyruvic acid in LLC-bearing mice particularly those fed the HFD. Time-restricted feeding shifted the metabolic profile of LLC-bearing mice towards that of non-LLC-bearing controls. CONCLUSION: Time-restricted feeding improves metabolic profile of LLC-bearing mice.


Assuntos
Carcinoma Pulmonar de Lewis/sangue , Jejum/sangue , Metabolômica , Animais , Carcinoma Pulmonar de Lewis/dietoterapia , Colestanol/sangue , Colesterol/sangue , Dieta Hiperlipídica/efeitos adversos , Modelos Animais de Doenças , Ácidos Docosa-Hexaenoicos/sangue , Jejum/fisiologia , Humanos , Insulina/sangue , Isoleucina/sangue , Ácido Láctico/sangue , Leucina/sangue , Camundongos , Metástase Neoplásica , Fenilalanina/sangue , Ácido Pirúvico/sangue , alfa-Tocoferol/sangue
8.
Chin J Nat Med ; 18(3): 178-185, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32245587

RESUMO

Enhanced glucose metabolism is one of the hallmarks of pancreatic cancer. MUC1, a transmembrane protein, is a global regulator of glucose metabolism and essential for progression of pancreatic cancer. To clarify the role of MUC1 in glucose metabolism, we knocked out MUC1 in Capan-1 and CFPAC-1 cells. MUC1 knockout (KO) cells uptook less glucose and secreted less lactate with a much lower proliferating rate. The mRNA level of key enzymes in glycolysis also decreased significantly in MUC1 KO cells. We also observed increased expression of breast cancer type 1 susceptibility protein (BRCA1) in MUC1 KO cells. Since BRCA1 has a strong inhibitory effect on glycolysis, we want to know whether the decreased glucose metabolism in MUC1 KO cells is due to increased BRCA1 expression. We treated wild type (WT) and MUC1 KO cells with BRCA1 inhibitor. BRCA1 inhibition significantly enhanced glucose uptake and lactate secretion in both WT and MUC1 KO cells. Expression of key enzymes in glycolysis also elevated after BRCA1 inhibition. Elevated glucose metabolism is known to facilitate cancer cells to gain chemoresistance. We treated MUC1 KO cells with gemcitabine and FOLFIRINOX in vitro and in vivo. The results showed that MUC1 KO sensitized pancreatic cancer cells to chemotherapy both in vitro and in vivo. In conclusion, we demonstrated that MUC1 promotes glycolysis through inhibiting BRCA1 expression. MUC1 may be a therapeutic target in pancreatic cancer treatment.


Assuntos
Proteína BRCA1/genética , Glucose/metabolismo , Glicólise , Mucina-1/metabolismo , Neoplasias Pancreáticas/metabolismo , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Linhagem Celular Tumoral , Proliferação de Células , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacologia , Fluoruracila/farmacologia , Regulação Neoplásica da Expressão Gênica , Técnicas de Inativação de Genes , Humanos , Irinotecano/farmacologia , Ácido Láctico/metabolismo , Leucovorina/farmacologia , Masculino , Camundongos Nus , Transplante de Neoplasias , Oxaliplatina/farmacologia , Neoplasias Pancreáticas/genética
9.
PLoS One ; 15(3): e0218302, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32191710

RESUMO

This study demonstrates that novel polymer production can be achieved by introducing pTAM, a broad-host-range plasmid expressing codon-optimized genes encoding Clostridium propionicum propionate CoA transferase (PctCp, Pct532) and a modified Pseudomonas sp. MBEL 6-19 polyhydroxyalkanoate (PHA) synthase 1 (PhaC1Ps6-19, PhaC1400), into phaC mutant strains of the native polymer producers Sinorhizobium meliloti and Pseudomonas putida. Both phenotypic analysis and gas chromatography analysis indicated the synthesis and accumulation of biopolymers in S. meliloti and P. putida strains. Expression in S. meliloti resulted in the production of PLA homopolymer up to 3.2% dried cell weight (DCW). The quaterpolymer P (3HB-co-LA-co-3HHx-co-3HO) was produced by expression in P. putida. The P. putida phaC mutant strain produced this type of polymer the most efficiently with polymer content of 42% DCW when cultured in defined media with the addition of sodium octanoate. This is the first report, to our knowledge, of the production of a range of different biopolymers using the same plasmid-based system in different backgrounds. In addition, it is the first time that the novel polymer (P(3HB-co-LA-co-3HHx-co-3HO)), has been reported being produced in bacteria.


Assuntos
Engenharia Genética , Ácido Láctico/metabolismo , Polímeros/metabolismo , Pseudomonas putida/metabolismo , Sinorhizobium meliloti/metabolismo , Caprilatos/farmacologia , Códon/genética , Fluorescência , Genes Bacterianos , Glucuronidase/metabolismo , Isopropiltiogalactosídeo/farmacologia , Fenótipo , Plasmídeos/metabolismo , Poliésteres/metabolismo , Poli-Hidroxialcanoatos/metabolismo , Pseudomonas putida/efeitos dos fármacos , Pseudomonas putida/genética , Sinorhizobium meliloti/efeitos dos fármacos , Sinorhizobium meliloti/genética
10.
Bioresour Technol ; 307: 123160, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32222692

RESUMO

This study evaluated a novel three-stage process devoted to the cascade production of lactate, biohydrogen and methane from tequila vinasse (TV), with emphasis on attaining a high and stable biohydrogen production rate (HPR) by utilizing lactate as biohydrogen precursor. In the first stage, tailored operating conditions applied to a sequencing batch reactor were effective in sustaining a lactate concentration of 12.4 g/L, corresponding to 89% of the total organic acids produced. In the second stage, the stimulation of lactate-centered dark fermentation which entails the decoupling of biohydrogen production from carbohydrates utilization was an effective approach enabling stable biohydrogen production, having HPR fluctuations less than 10% with a maximum HPR of 12.3 L/L-d and a biohydrogen yield of 3.1 L/LTV. Finally, 1.6 L CH4/L-d and 6.5 L CH4/LTV were obtained when feeding the biohydrogen fermentation effluent to a third methanogenic stage, yielding a global energy recovery of 267.5 kJ/LTV.


Assuntos
Hidrogênio , Ácido Láctico , Bebidas Alcoólicas , Reatores Biológicos , Fermentação , Metano
12.
Zhonghua Wei Zhong Bing Ji Jiu Yi Xue ; 32(1): 39-43, 2020 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-32148229

RESUMO

OBJECTIVE: To evaluate the prognostic value of arterial lactate (Lac) combined with central venous-to-arterial carbon dioxide difference to arterial-to-central venous oxygen content difference ratio (Pcv-aCO2/Ca-cvO2) in patients with septic shock following early fluid resuscitation. METHODS: A total of 97 patients with septic shock admitted to intensive care unit (ICU) of Lanzhou University Second Hospital from January 2017 to December 2019 were enrolled. The Pcv-aCO2/Ca-cvO2 ratio was calculated from blood gas analysis of radial artery and superior vena cava which was performed before resuscitation and at 6 hours of resuscitation at the same time. The patients were divided into death group and survival group according to the 28-day prognosis. The baseline data, acute physiology and chronic health evaluation II (APACHE II) score, sequential organ failure score (SOFA), clinical therapy, lactate clearance rate (LCR) at 6 hours, the length of ICU stay, hemodynamics and oxygen metabolism parameters before and after resuscitation were compared between the two groups. Risk factors were analyzed by multivariate Cox regression for 28-day mortality of patients with septic shock. The receiver operating characteristic (ROC) curve was plotted to assess the prognostic values of these factors for 28-day mortality. RESULTS: (1) Compared with the survival group, the patients in the death group showed significantly higher levels of APACHE II score (23.96±4.31 vs. 17.70±3.92) and SOFA score (12.74±2.80 vs. 9.23±2.43, both P < 0.01), significantly higher proportions of mechanical ventilation [85.2% (23/27) vs. 50.0% (35/70)] and continuous renal replacement therapy [CRRT; 51.9% (14/27) vs. 25.7% (18/70), both P < 0.05], a significantly more fluid replacement at 6 hours (L: 2.92±0.24 vs. 2.63±0.25, P < 0.01), a significantly lower level of LCR at 6 hours [(11.61±7.76)% vs. (27.67±13.71)%, P < 0.01], and a shorter length of ICU stay (days: 6.37±2.70 vs. 7.67±2.31, P < 0.05). (2) Compared with the survival group, the patients before resuscitation in the death group showed a significantly lower level of mean arterial pressure [MAP (mmHg, 1 mmHg = 0.133 kPa): 52.63±4.35 vs. 55.74±3.01, P < 0.01], significantly higher levels of Lac and Pcv-aCO2/Ca-cvO2 ratio [Lac (mmol/L): 7.13±1.75 vs. 5.22±1.36, Pcv-aCO2/Ca-cvO2 ratio: 1.67±0.29 vs. 1.48±0.22, both P < 0.01]; and the patients at 6 hours of resuscitation in the death group showed a significantly lower level of MAP (mmHg: 62.59±4.80 vs. 66.71±3.91, P < 0.01), significantly higher levels of central venous pressure (CVP), Lac, Pcv-aCO2 and Pcv-aCO2/Ca-cvO2 ratio [CVP (mmHg): 10.74±1.40 vs. 8.80±0.75, Lac (mmol/L): 6.36±1.86 vs. 3.90±1.95, Pcv-aCO2 (mmHg): 7.59±2.02 vs. 4.34±1.37, Pcv-aCO2/Ca-cvO2 ratio: 1.87±0.51 vs. 1.03±0.27, all P < 0.01]. (3) Multivariate Cox regression analysis showed that the independent risk factors for 28-day mortality in patients with septic shock were Lac and Pcv-aCO2/Ca-cvO2 ratio whether before or at 6 hours of resuscitation [Lac before resuscitation: relative risk (RR) = 1.434, 95% confidence interval (95%CI) was 1.070-1.922, P = 0.016; Lac at 6 hours of resuscitation: RR = 1.564, 95%CI was 1.202-2.035, P = 0.001; Pcv-aCO2/Ca-cvO2 ratio before resuscitation: RR = 2.828, 95%CI was 1.108-4.207, P = 0.038; Pcv-aCO2/Ca-cvO2 ratio at 6 hours of resuscitation: RR = 4.386, 95%CI was 2.842-5.730, P = 0.000]. (4) ROC curve analysis showed that Lac and Pcv-aCO2/Ca-cvO2 ratio at 6 hours of resuscitation had predictive value for the prognosis of patients with septic shock, the area under ROC curve (AUC) was 0.849 (95%CI was 0.762-0.914) and 0.905 (95%CI was 0.828-0.955), respectively. However, the predictive value of Lac combined with Pcv-aCO2/Ca-cvO2 ratio in patients with septic shock was significantly higher than Lac [AUC (95%CI): 0.976 (0.923-0.996) vs. 0.849 (0.762-0.914), Z = 3.354, P = 0.001], the sensitivity was 97.14%, and the specificity was 88.89%. CONCLUSIONS: Lac and Pcv-aCO2/Ca-cvO2 ratio are independent risk factors for predicting 28-day mortality in patients with septic shock. Lac combined with Pcv-aCO2/Ca-cvO2 ratio can assess the prognosis of patients with septic shock more accurately.


Assuntos
Gasometria , Dióxido de Carbono/sangue , Ácido Láctico/sangue , Oxigênio/sangue , Choque Séptico/diagnóstico , Hidratação , Humanos , Prognóstico , Fatores de Risco , Choque Séptico/mortalidade
13.
Adv Exp Med Biol ; 1219: 51-74, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32130693

RESUMO

Reprogramming of energy metabolism is a key hallmark of cancer. Most cancer cells display a glycolytic phenotype, with increased glucose consumption and glycolysis rates, and production of lactate as the end product, independently of oxygen concentrations. This phenomenon, known as "Warburg Effect", provides several survival advantages to cancer cells and modulates the metabolism and function of neighbour cells in the tumour microenvironment. However, due to the presence of metabolic heterogeneity within a tumour, cancer cells can also display an oxidative phenotype, and corruptible cells from the microenvironment become glycolytic, cooperating with oxidative cancer cells to boost tumour growth. This phenomenon is known as "Reverse Warburg Effect". In either way, lactate is a key mediator in the metabolic crosstalk between cancer cells and the microenvironment, and lactate transporters are expressed differentially by existing cell populations, to support this crosstalk.In this review, we will focus on lactate and on lactate transporters in distinct cells of the tumour microenvironment, aiming at a better understanding of their role in the acquisition and maintenance of the direct/reverse "Warburg effect" phenotype, which modulate cancer progression.


Assuntos
Ácido Láctico/metabolismo , Transportadores de Ácidos Monocarboxílicos/metabolismo , Neoplasias/metabolismo , Glicólise , Humanos , Microambiente Tumoral
14.
Ann Rheum Dis ; 79(4): 499-506, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32079570

RESUMO

OBJECTIVES: The differential diagnosis of seronegative rheumatoid arthritis (negRA) and psoriasis arthritis (PsA) is often difficult due to the similarity of symptoms and the unavailability of reliable clinical markers. Since chronic inflammation induces major changes in the serum metabolome and lipidome, we tested whether differences in serum metabolites and lipids could aid in improving the differential diagnosis of these diseases. METHODS: Sera from negRA and PsA patients with established diagnosis were collected to build a biomarker-discovery cohort and a blinded validation cohort. Samples were analysed by proton nuclear magnetic resonance. Metabolite concentrations were calculated from the spectra and used to select the variables to build a multivariate diagnostic model. RESULTS: Univariate analysis demonstrated differences in serological concentrations of amino acids: alanine, threonine, leucine, phenylalanine and valine; organic compounds: acetate, creatine, lactate and choline; and lipid ratios L3/L1, L5/L1 and L6/L1, but yielded area under the curve (AUC) values lower than 70%, indicating poor specificity and sensitivity. A multivariate diagnostic model that included age, gender, the concentrations of alanine, succinate and creatine phosphate and the lipid ratios L2/L1, L5/L1 and L6/L1 improved the sensitivity and specificity of the diagnosis with an AUC of 84.5%. Using this biomarker model, 71% of patients from a blinded validation cohort were correctly classified. CONCLUSIONS: PsA and negRA have distinct serum metabolomic and lipidomic signatures that can be used as biomarkers to discriminate between them. After validation in larger multiethnic cohorts this diagnostic model may become a valuable tool for a definite diagnosis of negRA or PsA patients.


Assuntos
Artrite Psoriásica/sangue , Artrite Reumatoide/sangue , Acetatos/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Alanina/sangue , Aminoácidos/sangue , Artrite Psoriásica/diagnóstico , Artrite Reumatoide/diagnóstico , Artrite Reumatoide/imunologia , Colina/sangue , Creatina/sangue , Diagnóstico Diferencial , Feminino , Humanos , Ácido Láctico/sangue , Lipidômica , Lipídeos/sangue , Masculino , Metaboloma , Metabolômica , Pessoa de Meia-Idade , Fosfocreatina/sangue , Espectroscopia de Prótons por Ressonância Magnética , Ácido Succínico/sangue
15.
Invest Ophthalmol Vis Sci ; 61(2): 7, 2020 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-32031579

RESUMO

Purpose: Confirm that the corneal endothelial pump uses a lactate-coupled water efflux mechanism. Methods: Corneal thickness, lactate efflux, and stromal [lactate] were measured in de-epithelialized swollen and nonswollen ex vivo-mounted rabbit corneas perfused with bicarbonate-rich and bicarbonate-free Ringers, ouabain, or acetazolamide to determine if the relationships among these parameters were similar to previous data using intact corneas. The role of barrier function was tested by perfusion with calcium-free EGTA. Predictions of [lactate] in endothelial dystrophy were examined in the Slc4a11 knock out mouse. Results: De-epithelialized corneal swelling, lactate efflux, and stromal [lactate] in response to bicarbonate-free Ringers, ouabain, and acetazolamide perfusion had the same relationship as in intact corneas. The absolute amount of lactate efflux and stromal [lactate] in the de-epithelialized corneas was about half of intact corneas. De-epithelialized, swollen corneas deswelled fully with bicarbonate-rich, partially in the presence of acetazolamide, but continued to swell with bicarbonate-free or ouabain. The relationship among corneal thickness, lactate efflux, and [lactate] was the same as with nonswollen de-epithelialized corneas. In intact corneas swollen by perfusion with calcium-free EGTA, the relationship between swelling and lactate flux was the inverse of control corneas. The relationship between corneal swelling and [lactate] of intact corneas exposed to ouabain, but perfused with 7 mM lactate to simulate aqueous humor, was the same as without lactate. Corneal [lactate] in Slc4a11 knock out was twice that of wild type. Conclusions: The corneal endothelial pump works via a lactate efflux mechanism that requires an intact osmotic barrier.


Assuntos
Epitélio Posterior/metabolismo , Ácido Láctico/metabolismo , Animais , Proteínas de Transporte de Ânions/metabolismo , Transporte Biológico Ativo/fisiologia , Córnea/metabolismo , Edema da Córnea/fisiopatologia , Inibidores Enzimáticos/farmacologia , Feminino , Masculino , Camundongos Knockout , Ouabaína/farmacologia , Coelhos , ATPase Trocadora de Sódio-Potássio/antagonistas & inibidores , Simportadores/metabolismo
16.
PLoS One ; 15(2): e0223870, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32092083

RESUMO

Lactate oxidases belong to a group of FMN-dependent enzymes and they catalyze a conversion of lactate to pyruvate with a release of hydrogen peroxide. Hydrogen peroxide is also utilized as a read out in biosensors to quantitate lactate levels in biological samples. Aerococcus viridans lactate oxidase is the best characterized lactate oxidase and our knowledge of lactate oxidases relies largely to studies conducted with that particular enzyme. Pediococcus acidilactici lactate oxidase is also commercially available for e.g. lactate measurements, but this enzyme has not been characterized in detail before. Here we report structural characterization of the recombinant enzyme and its co-factor dependent oligomerization. The crystal structures revealed two distinct conformations in the loop closing the active site, consistent with previous biochemical studies implicating the role of loop in catalysis. Despite the structural conservation of active site residues, we were not able to detect either oxidase or monooxygenase activity when L-lactate was used as a substrate. Pediococcus acidilactici lactate oxidase is therefore an example of a misannotation of an FMN-dependent enzyme, which catalyzes likely a so far unknown oxidation reaction.


Assuntos
Mononucleotídeo de Flavina/farmacologia , Oxigenases de Função Mista/metabolismo , Pediococcus acidilactici/enzimologia , Multimerização Proteica/efeitos dos fármacos , Catálise , Domínio Catalítico , Cristalografia por Raios X , Ácido Láctico/metabolismo , Pediococcus acidilactici/metabolismo , Proteínas Recombinantes
17.
Medicine (Baltimore) ; 99(7): e18894, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32049788

RESUMO

Thiamine is an essential co-factor for aerobic metabolism. Both thiamine deficiency and sepsis may be associated with hyperlactatemia and hypotension. We assessed the relationship between thiamine compounds, lactate concentrations and clinical outcomes in septic patients.We undertook a prospective observational single-center study. Erythrocyte levels of total thiamine, free thiamine, thiamine mono, di and triphosphate (TMP, TDP, and TTP respectively), the erythrocyte transketolase activity (ETKA) and the effect of thiamine diphosphate on ETKA were measured in septic patients by high performance liquid chromatography and correlated with arterial lactate. Vital status at the end of intensive care unit stay was recorded.Overall, 28 patients suffering from sepsis were included. Median (interquartile range [IQR]) age was 60 [44-77.3] years, 15 (53.6%) patients were male, median [IQR] simplified acute physiology score II was 40 [27-50]. There was no correlation between total thiamine and lactate levels (P = .33). There was no correlation between free thiamine (P = .81), TMP (P = .71), TDP (P = .31), TTP (P = .86), and lactate levels in our population. There was no correlation between ETKA (P = .58) or the effect of TDP on ETKA (P = .40) and lactate concentration. Total thiamine and TDP concentration were significantly higher in intensive care unit (ICU) survivors than in nonsurvivors (P = .03 and P = .03). The effect of TDP on ETKA was significantly higher in nonsurvivors compared to survivors (P = .04).We found no correlation between thiamine compounds and lactate concentration in sepsis. Thiamine deficiency in sepsis may be associated with ICU-mortality.


Assuntos
Ácido Láctico/sangue , Sepse/sangue , Tiamina/sangue , Adulto , Idoso , Feminino , Humanos , Unidades de Terapia Intensiva , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Sepse/mortalidade , Transcetolase/metabolismo
18.
PLoS One ; 15(2): e0229066, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32053674

RESUMO

A footbath-based control program for ovine footrot, a contagious disease caused by Dichelobacter nodosus, will be implemented in Switzerland. The currently used footbath disinfectants formaldehyde, zinc sulfate and copper sulfate are carcinogenic or environmental pollutants. Hence, the aim of this study was to identify alternative disinfectants, which are highly effective, non-carcinogenic, environmentally acceptable, inexpensive, available as concentrate and suitable for licensing. The antimicrobial effect of a series of potential chemicals such as lactic acid, propionic acid, hydrogen peroxide, sodium hypochlorite, octenidine dihydrochloride, chlorocresol, Ampholyt 20 and the registered biocide DESINTEC® Hoof Care Special D (Desintec) were investigated by culture based in vitro testing. The microcidal effect of various Desintec concentrations were then compared against routinely used 4% formaldehyde and 10% zinc sulfate in ex vivo assays on sheep feet from slaughter. For this purpose a newly established PMA (propidium monoazid) real-time PCR using the improved dye PMAxx™ was applied that allows discrimination of viable and dead D. nodosus. In the ex vivo experiments, 4% formaldehyde was significantly more effective than 10% zinc sulfate and was chosen as positive control for assessing the new disinfectant. The disinfectant effect of Desintec in a minimal concentration of 6% was equally effective as 4% formaldehyde, meaning that it offers a comparable antimicrobial effect against virulent D. nodosus. In conclusion, Desintec is a promising disinfectant for replacing formaldehyde, copper sulfate and zinc sulfate in footbaths against footrot.


Assuntos
Dichelobacter nodosus/efeitos dos fármacos , Desinfetantes/farmacologia , Animais , Sulfato de Cobre/farmacologia , Formaldeído/farmacologia , Ácido Láctico/farmacologia , Reação em Cadeia da Polimerase em Tempo Real , Ovinos , Virulência , Sulfato de Zinco/farmacologia
19.
Bioresour Technol ; 302: 122881, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32014732

RESUMO

In this study, a reliable approach using ammonia nitrogen was proposed to increase lactate production during semi-continuous food waste (FW) fermentation under mesophilic conditions. Both free ammonia nitrogen (FAN) and ammonium ion (NH4+-N) were present in mesophilic reactors, with a wide FAN/NH4+-N ratio variation due to the intermittent pH control. The investigation of responsible mechanisms revealed that the increased production yield of LA was associated with the acceleration of solubilization, hydrolysis, glycolysis and acidification. The presence of FAN and NH4+-N in proper concentrations increased lactate production by 2.4 folds and recovered lactate production to 24.5 g COD/L from low rate control reactor (9.6 g COD/L) under mesophilic conditions. Furthermore, the microorganisms responsible for LA accumulation (Bavariicoccus, Enterococcus, Bifidobacterium and Corynebacterium) were selectively enriched, and KEGG (Kyoto Encyclopedia of Genes and Genomes) pathways associated with carbohydrate transport and LA production were enhanced in nitrogen fed reactors.


Assuntos
Amônia , Eliminação de Resíduos , Reatores Biológicos , Fermentação , Alimentos , Ácido Láctico
20.
Invest Ophthalmol Vis Sci ; 61(2): 10, 2020 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-32049346

RESUMO

Purpose: Aiming to clarify the metabolic interrogation in cell fate decision of cultured human corneal endothelial cells (cHCECs). Methods: To analyze the metabolites in the culture supernatants (CS), 34 metabolome measurements were carried out for mature differentiated and a variety of cHCECs with cell state transition through a facility service. Integrated proteomics research for cell lysates by liquid chromatography-tandem mass spectrometry (LC-MS/MS) was performed for 3 aliquots of each high-quality or low-quality cHCEC subpopulations (SP). The investigations for the focused genes involved in cHCEC metabolism were performed by using DAVID and its options "KEGG_PATHWAY." Results: The clusters of metabolites coincided well with the distinct content of CD44-/+ SPs. Both secreted pyruvic acid and lactic acid in the CS were negatively correlated with the content of high-quality SPs. Lactic acid and pyruvic acid in the CS exhibited the positive correlation with that of Ile, Leu, and Ser, whereas the negative correlation was with glutamine. Platelet-derived growth factor-ßß in the CS negatively correlated with lactic acid in CS, indicating indirectly the positive correlation with the content of CD44-/+ SPs. Upregulated glycolytic enzymes and influx of glutamine to the tricarboxylic acid cycle may be linked with a metabolic rewiring converting oxidative metabolism in mature differentiated CD44-/+SPs into a glycolytic flux-dependent state in immature SPs with cell state transition. Conclusions: The findings suggest that the cell fate decision of cHCECs may be dictated at least partly through metabolic rewiring.


Assuntos
Células Endoteliais/metabolismo , Epitélio Posterior/metabolismo , Biomarcadores/metabolismo , Diferenciação Celular/fisiologia , Células Cultivadas , Epitélio Posterior/citologia , Feminino , Humanos , Ácido Láctico/metabolismo , Masculino , Metaboloma/fisiologia , Fosforilação/fisiologia , Proteoma/metabolismo , Ácido Pirúvico/metabolismo
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