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1.
Cancer Radiother ; 24(4): 323-331, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32532578

RESUMO

PURPOSE: The purpose of this study was to evaluate MRI and fluorocholine PET/CT diagnostic performances for the detection of local recurrence following prostate brachytherapy for localised prostate cancer. MATERIAL AND METHODS: In this single-centre study, we retrospectively reviewed data from 21 patients treated by brachytherapy for localised prostate cancer and diagnosed with biochemical recurrence according to Phoenix Criteria, who underwent MRI and fluorocholine PET/CT. We included patients with local relapse suspicion according to imaging exams, with biopsy for the final assessment of local recurrence. Patient analysis data were supplemented by segment analysis using an 8-segment model. RESULTS: The fluorocholine PET/CT was positive for 81% and negative for 19% of patients. The sensitivity and specificity were 92% and 33% with diagnosis accuracy of 67%. The MRI was positive for 57% and negative for 43% of patients. The sensitivity and specificity were 67% and 56% with diagnosis accuracy of 62%. There was no statistically significant difference between fluorocholine PET/CT and MRI accuracy (P=0.63). On a segment-based analysis, the sensitivity and specificity were 44% and 82% for fluorocholine PET/CT with diagnosis accuracy of 78%. For MRI, specificity was 91% diagnosis accuracy was 82%. CONCLUSION: Both MRI and fluorocholine PET/CT permit to highlight local recurrence sites after prostate brachytherapy. Confirmation biopsies are, however, necessary since this accuracy is insufficient.


Assuntos
Braquiterapia , Imagem por Ressonância Magnética/métodos , Recidiva Local de Neoplasia/diagnóstico por imagem , Tomografia Computadorizada com Tomografia por Emissão de Pósitrons/métodos , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/radioterapia , Idoso , Biópsia , Colina/análogos & derivados , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Próstata/diagnóstico por imagem , Próstata/patologia , Neoplasias da Próstata/patologia , Compostos Radiofarmacêuticos , Dosagem Radioterapêutica , Estudos Retrospectivos , Sensibilidade e Especificidade
3.
Radiol Med ; 125(7): 668-673, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32166718

RESUMO

PURPOSE: Salvage radiotherapy is generally considered as the standard treatment for biochemical relapse after surgery. Best results have been obtained with a PSA value < 0.5 ng/ml at relapse, while 60-66 Gy is deemed as standard total dose. Modern imaging, as dynamic-18F-choline PET/CT may identify site of recurrence, allowing dose escalation to a biological target volume. METHODS: Hundred and fifty patients showed a local relapse at dynamic-18F-choline PET/CT at time of biochemical recurrence. High-dose salvage radiotherapy was delivered up to total dose of 80 Gy to 18F-choline PET/CT positive area. Toxicity and relapse-free survival were recorded. RESULTS: Median PSA value at the beginning of salvage radiotherapy was 0.47 ng/ml (range 0.2-17.5 ng/ml). One-hundred and thirty nine patients (93%) completed salvage radiotherapy without interruptions. Acute gastrointestinal grade ≥ 2 toxicity was recorded in 13 patients (9%), acute genitourinary grade ≥ 2 toxicity in 2 patients (1.4%). One patient (0.7%) experienced late gastrointestinal grade 4 toxicity and 2 patients (1.4%) late acute genitourinary grade 3 toxicity. With a median follow-up of 63.5 months, 5 and 7-years relapse-free survival were 70% and 60.7%, respectively. CONCLUSION: With a median follow-up of 5 years the present study confirms that high-dose salvage radiotherapy to a biological target volume is feasible, with low rate of late toxicity and promising activity.


Assuntos
Recidiva Local de Neoplasia/diagnóstico por imagem , Tomografia Computadorizada com Tomografia por Emissão de Pósitrons , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/radioterapia , Terapia de Salvação/métodos , Idoso , Idoso de 80 Anos ou mais , Colina/análogos & derivados , Progressão da Doença , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Antígeno Prostático Específico/sangue , Compostos Radiofarmacêuticos , Dosagem Radioterapêutica
4.
Am J Clin Nutr ; 111(6): 1226-1234, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32055828

RESUMO

BACKGROUND: Trimethylamine N-oxide (TMAO), a compound derived from diet and metabolism by the gut microbiome, has been associated with several chronic diseases, although the mechanisms of action are not well understood and few human studies have investigated microbes involved in its production. OBJECTIVES: Our study aims were 1) to investigate associations of TMAO and its precursors (choline, carnitine, and betaine) with inflammatory and cardiometabolic risk biomarkers; and 2) to identify fecal microbiome profiles associated with TMAO. METHODS: We conducted a cross-sectional analysis using data collected from 1653 participants (826 men and 827 women, aged 60-77 y) in the Multiethnic Cohort Study. Plasma concentrations of TMAO and its precursors were measured by LC-tandem MS. We also analyzed fasting blood for markers of inflammation, glucose and insulin, cholesterol, and triglycerides (TGs), and further measured blood pressure. Fecal microbiome composition was evaluated by sequencing the 16S ribosomal RNA gene V1-V3 region. Associations of TMAO and its precursors with disease risk biomarkers were assessed by multivariable linear regression, whereas associations between TMAO and the fecal microbiome were assessed by permutational multivariate ANOVA and hurdle regression models using the negative binomial distribution. RESULTS: Median (IQR) concentration of plasma TMAO was 3.05 µmol/L (2.10-4.60 µmol/L). Higher concentrations of TMAO and carnitine, and lower concentrations of betaine, were associated with greater insulin resistance (all P < 0.02). Choline was associated with higher systolic blood pressure, TGs, lipopolysaccharide-binding protein, and lower HDL cholesterol (P ranging from <0.001 to 0.03), reflecting an adverse cardiometabolic risk profile. TMAO was associated with abundance of 13 genera (false discovery rate < 0.05), including Prevotella, Mitsuokella, Fusobacterium, Desulfovibrio, and bacteria belonging to the families Ruminococcaceae and Lachnospiraceae, as well as the methanogen Methanobrevibacter smithii. CONCLUSIONS: Plasma TMAO concentrations were associated with a number of trimethylamine-producing bacterial taxa, and, along with its precursors, may contribute to inflammatory and cardiometabolic risk pathways.


Assuntos
Betaína/sangue , Doenças Cardiovasculares/sangue , Carnitina/sangue , Colina/sangue , Microbioma Gastrointestinal , Metilaminas/sangue , Adiposidade , Idoso , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Bactérias/metabolismo , Biomarcadores/sangue , Doenças Cardiovasculares/etnologia , Doenças Cardiovasculares/imunologia , Doenças Cardiovasculares/microbiologia , Estudos de Coortes , Estudos Transversais , Feminino , Humanos , Masculino , Metilaminas/metabolismo , Pessoa de Meia-Idade
5.
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
6.
Bioresour Technol ; 303: 122897, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32036329

RESUMO

To establish an environmentally friendly and cheaper method to delignify lignocellulosic biomass feedstocks, deep eutectic solvents (DESs) were investigated as a green alternatives to conventional solvents. Six different DESs were facilely prepared and used to delignify miscanthus and birchwood feedstocks, including monocarboxylic acid/choline chloride (ChCl), dicarboxylic acid/ChCl and polyalcohol/ChCl. The enhanced delignification efficiency was evaluated in relation to the nature of the hydrogen bond donors and acid strength of DES. The largest extraction of lignin from the miscanthus and birchwood was achieved using ChCl.formic acid and ChCl.oxalic acid DES, respectively. The TGA and 13C NMR characterization results of the extracted lignin samples indicated that the different types of lignin were produced using different DESs. The reaction optimization results showed an increase in lignin extraction with increasing temperature from 60 to 130 °C. However, the optimal reaction time was different, 30 min for miscanthus and 60 min for birchwood. A convenient and reliable method for the quantification of lignin was developed using UV-Vis spectrophotometry.


Assuntos
Lignina , Micro-Ondas , Biomassa , Colina , Solventes
7.
Macromol Rapid Commun ; 41(4): e1900611, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31958194

RESUMO

Herein, it is reported for the first time that when mixed with choline chloride, itaconic acid (IA), normally a low-reactive vinyl monomer, undergoes initiator-free radical polymerization under normal daylight. Furthermore, the process results in the formation of abnormally high-molecular-weight poly(itaconic acid) derivatives with Mw greater than ≈800 000 g mol-1 . Detailed 1D/2D NMR studies indicate that the polymers have two types of ionizable moieties, that is, anionic carboxylic and cationic choline ester groups in an average molar ratio of 12:1. Potentiometric titration shows polyampholyte behavior of the polymers. Tentative mechanistic studies reveal that the daylight-induced polymerization is initiated by species generated via interactions of near UV light with IA. However, EPR findings show that choline also participates in secondary radical reactions. The obtained polyampholytes are useful bio-based materials for fast and straightforward fabrication of polymer-clay nanocomposite hydrogels with excellent mechanical properties.


Assuntos
Radicais Livres/química , Polímeros/síntese química , Succinatos/química , Colina/química , Luz , Substâncias Macromoleculares/química , Peso Molecular , Polimerização/efeitos da radiação , Polímeros/química , Raios Ultravioleta
8.
Food Chem ; 314: 126097, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-31945551

RESUMO

A novel approach for effective sample pretreatment of food was developed. This approach was based on in situ deep eutectic mixtures formation between analytes (hydrogen bond donors) and choline chloride (a hydrogen bond acceptor) supported in a hydrophilic porous membrane. By this action, the analytes were extracted and retained into the hydrophilic porous membrane. Finally, the hydrophilic porous membrane containing the analytes was transferred into an aqueous phase and back-extraction occurred due to deep eutectic mixture decomposition in the aqueous phase. The developed approach was applied to the HPLC-FLD determination of phenols (phenol, o-cresol, p-cresol, eugenol, isoeugenol and guaiacol) in smoked food samples. The limits of detection, calculated from a blank test based on 3σ, were 0.3 µg kg-1 for phenol, o-cresol, p-cresol; 0.6 µg kg-1 for eugenol, isoeugenol; and 1 µg kg-1 for guaiacol.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Análise de Alimentos/métodos , Conservação de Alimentos/métodos , Microextração em Fase Líquida/métodos , Fenóis/análise , Colina/química , Análise de Alimentos/instrumentação , Ligação de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Limite de Detecção , Microextração em Fase Líquida/instrumentação , Membranas Artificiais , Fenóis/química , Solventes/química
9.
Clin Nucl Med ; 45(3): e154-e155, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31977458

RESUMO

Amyloidosis is a rare hereditary or acquired protein deposition disorder with different etiologies, characterized by pathological protein deposition essentially in nearly any organs or tissues. There are 2 major forms: primary and secondary amyloidosis. Moreover, it is possible to have systemic or localized disease. The localized form of amyloidosis affecting the small intestine is rare, and it is characterized by the formation of precursor proteins at the site of the lesion. We report a case of localized small bowel amyloidosis studied by F-choline and F-FDG-iodinated PET/CT performed for staging an aggressive prostatic cancer.


Assuntos
Amiloidose de Cadeia Leve de Imunoglobulina/diagnóstico por imagem , Intestino Delgado/diagnóstico por imagem , Tomografia Computadorizada com Tomografia por Emissão de Pósitrons , Idoso , Colina/análogos & derivados , Fluordesoxiglucose F18 , Humanos , Masculino , Compostos Radiofarmacêuticos
10.
Bioresour Technol ; 301: 122684, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31954964

RESUMO

In this study, a novel Type II deep eutectic solvent (DES) namely, choline chloride:copper(II) chloride dihydrate (ChCl:CuCl2·2H2O) was used to pretreat oil palm fronds (OPFs). The sequential pretreatment with alkaline hydrogen peroxide (0.25 vol%, 90 min) at ambient conditions and a Type II DES (90 °C, 3 h) at a later stage resulted in a delignification of 55.14% with high xylan (80.79%) and arabinan (98.02%) removals. The characterizations of pretreated OPFs confirmed the excellent performance of DES in OPF fractionation. Thus, the application of a Type II DES at ambient pressure and relatively lower temperature was able to improve the lignin and hemicellulose removals from OPFs.


Assuntos
Colina , Peróxido de Hidrogênio , Biomassa , Cobre , Lignina , Solventes
11.
Medicine (Baltimore) ; 99(2): e18681, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31914064

RESUMO

Hyperparathyroidism is a common endocrine disorder. The precise localization of causal parathyroid gland is crucial to guide surgical treatment. Several studies report the added value of 18F-fluorocholine (FCH) positron emission tomography-computed tomography (PET/CT) as second line imaging but rely on suboptimal first-line imaging using 99mTc-sestaMIBI dual phase scintigraphy. The aim of this study is to evaluate the percentage of successful parathyroid localization with FCH PET/CT after failure of a more sensitive first-line detection protocol associating neck ultrasonography and 99mTc-Pertechnetate/99mTc-sestaMIBI dual tracer subtraction scintigraphy.We included retrospectively 47 patients who underwent a FCH PET/CT as second line imaging for biologically proven primary hyperparathyroidism from November 2016 to October 2018 in Godinot Institute (Reims, France). 99mTc-Pertechnetate/99mTc-sestaMIBI dual tracer subtraction scintigraphy and neck ultrasonography were used as first-line imaging and failed to localize the causal parathyroid lesion in all cases.FCH PET/CT demonstrated at least 1 parathyroid target lesion in 29 patients (62%). 21/29 patients underwent surgery. Target lesions corresponded histologically to hyperfunctioning parathyroid glands for all 21 patients and surgery was followed by hyperparathyroidism biological resolution. Calcium serum levels were associated to FCH PET/CT positivity (P = .002) and a trend toward significance was seen for Parathyroid hormone (PTH) levels (P = .09).FCH PET/CT is a promising tool in second-line parathyroid imaging. Large prospective studies and cost-effectiveness analyses are needed to precise its role.


Assuntos
Colina/análogos & derivados , Radioisótopos de Flúor/administração & dosagem , Hiperparatireoidismo/diagnóstico por imagem , Glândulas Paratireoides/diagnóstico por imagem , Tomografia Computadorizada com Tomografia por Emissão de Pósitrons/métodos , Idoso , Idoso de 80 Anos ou mais , Colina/administração & dosagem , Feminino , Humanos , Hiperparatireoidismo/patologia , Masculino , Pessoa de Meia-Idade , Glândulas Paratireoides/patologia , Cintilografia/métodos , Estudos Retrospectivos , Tecnécio Tc 99m Sestamibi/administração & dosagem
12.
Am J Clin Nutr ; 111(3): 644-656, 2020 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-31915809

RESUMO

BACKGROUND: Choline-related nutrients are dietary precursors of a gut microbial metabolite, trimethylamine-N-oxide, which has been linked to cardiometabolic diseases and related death. However, epidemiologic evidence on dietary choline and mortality remains limited, particularly among nonwhite populations. OBJECTIVES: This study aimed to investigate the associations of choline-related nutrients with cardiometabolic and all-cause mortality among black and white Americans and Chinese adults. METHODS: Included were 49,858 blacks, 23,766 whites, and 134,001 Chinese, aged 40-79 y, who participated in 3 prospective cohorts and lived ≥1 y after enrollment. Cox regression models were used to estimate HRs and 95% CIs for cardiometabolic [e.g., ischemic heart disease (IHD), stroke, and diabetes] and all-cause deaths. To account for multiple testing, P values < 0.003 were considered significant. RESULTS: Mean choline intake among blacks, whites, and Chinese was 404.1 mg/d, 362.0 mg/d, and 296.8 mg/d, respectively. During a median follow-up of 11.7 y, 28,673 deaths were identified, including 11,141 cardiometabolic deaths. After comprehensive adjustments, including for overall diet quality and disease history, total choline intake was associated with increased cardiometabolic mortality among blacks and Chinese (HR for highest compared with lowest quintile: 1.26; 95% CI: 1.13, 1.40 and HR: 1.23; 95% CI: 1.11, 1.38, respectively; both P-trend < 0.001); among whites, the association was weaker (HR: 1.12; 95% CI: 0.95, 1.33; P-trend = 0.02). Total choline intake was also associated with diabetes and all-cause mortality in blacks (HR: 1.66; 95% CI: 1.26, 2.19 and HR: 1.20; 95% CI: 1.12, 1.29, respectively), with diabetes mortality in Chinese (HR: 2.24; 95% CI: 1.68, 2.97), and with IHD mortality in whites (HR: 1.31; 95% CI: 1.02, 1.69) (all P-trend < 0.001). The choline-mortality association was modified by alcohol consumption and appeared stronger among individuals with existing cardiometabolic disease. Betaine intake was associated with increased cardiometabolic mortality in Chinese only (HR: 1.16; 95% CI: 1.08, 1.25; P-trend < 0.001). CONCLUSIONS: High choline intake was associated with increased cardiometabolic mortality in racially diverse populations.


Assuntos
Doenças Cardiovasculares/etnologia , Doenças Cardiovasculares/mortalidade , Colina/metabolismo , Adulto , Grupo com Ancestrais do Continente Africano , Idoso , Grupo com Ancestrais do Continente Asiático , Doenças Cardiovasculares/metabolismo , Grupo com Ancestrais do Continente Europeu , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
13.
Nat Commun ; 11(1): 388, 2020 01 20.
Artigo em Inglês | MEDLINE | ID: mdl-31959751

RESUMO

Bacterial microcompartments (BMCs) are prokaryotic organelles consisting of a protein shell and an encapsulated enzymatic core. BMCs are involved in several biochemical processes, such as choline, glycerol and ethanolamine degradation and carbon fixation. Since non-native enzymes can also be encapsulated in BMCs, an improved understanding of BMC shell assembly and encapsulation processes could be useful for synthetic biology applications. Here we report the isolation and recombinant expression of BMC structural genes from the Klebsiella pneumoniae GRM2 locus, the investigation of mechanisms behind encapsulation of the core enzymes, and the characterization of shell particles by cryo-EM. We conclude that the enzymatic core is encapsulated in a hierarchical manner and that the CutC choline lyase may play a secondary role as an adaptor protein. We also present a cryo-EM structure of a pT = 4 quasi-symmetric icosahedral shell particle at 3.3 Å resolution, and demonstrate variability among the minor shell forms.


Assuntos
Proteínas de Bactérias/metabolismo , Klebsiella pneumoniae/citologia , Liases/metabolismo , Organelas/ultraestrutura , Proteínas de Bactérias/genética , Colina/metabolismo , Microscopia Crioeletrônica , Loci Gênicos , Klebsiella pneumoniae/enzimologia , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/ultraestrutura , Liases/genética , Organelas/enzimologia , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Biologia Sintética
14.
J Dairy Sci ; 103(3): 2200-2216, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31954584

RESUMO

Objectives were to evaluate the effect of prepartum energy intake and peripartal supplementation of ruminally protected choline (RPC) on select indicators of immune status in blood plasma and on lipopolysaccharide-stimulated blood cells ex vivo. At 47 ± 6 d before the expected calving date, 93 multiparous Holstein cows were assigned randomly to 1 of 4 dietary treatments in a 2 × 2 factorial arrangement. Cows were fed energy to excess [EXE; 1.63 Mcal of net energy for lactation (NEL)/kg of dietary dry matter (DM)] or to maintenance (MNE; 1.40 Mcal of NEL/kg of dietary DM) ad libitum throughout the nonlactating period. The RPC was fed at 0 or 60 g/d to supply 0 or 12.9 g/d of choline ions top-dressed for 17 ± 4.6 d prepartum through 21 d postpartum. After calving, cows were fed the same methionine-supplemented diet, apart from RPC supplementation. During the last 2 wk before calving and during the first 5 wk postpartum, blood was sampled repeatedly and analyzed for cell types, acute-phase proteins, tumor necrosis factor-α (TNFα), and neutrophil function. Samples of whole blood were collected at 3 and 14 DIM and stimulated with 1 µg/mL lipopolysaccharide (LPS) in vitro for 6 and 24 h. After 6 h of LPS exposure, peripheral blood leucocytes (PBL) were harvested, and relative transcript abundance for select cytokines were measured. Supernatant was analyzed for TNFα after 24 h of LPS exposure. The PBL from cows fed EXE diets during the whole dry period had increased transcripts for the proinflammatory cytokines CXCL8 and TNF, although the plasma concentrations of the acute-phase proteins haptoglobin and fibrinogen, and the killing activity of the blood neutrophils in the postpartum period, were not affected by feeding different energy levels prepartum. Feeding RPC to cows overfed energy prepartum modulated their inflammatory state, as evidenced by decreased IL6 in PBL and reduced mean fluorescence intensity of CD14 during the postpartum period, compared with cows not fed RPC. Feeding RPC also decreased TNFα protein production, abundances of IL1B, CXCL8, and TNF transcripts, and mean fluorescence intensity of CD80 of PBL stimulated by LPS, regardless of prepartum energy intake. In contrast, proportions of blood neutrophils undergoing phagocytosis and oxidative burst were increased at 17 d postpartum in cows supplemented with RPC. Collectively, these data indicate that transition cows supplemented with RPC experienced less inflammation, which may partially explain increased milk production in cows supplemented with RPC.


Assuntos
Imunidade Adaptativa/efeitos dos fármacos , Bovinos/imunologia , Colina/administração & dosagem , Suplementos Nutricionais/análise , Ingestão de Energia , Leite/metabolismo , Animais , Biomarcadores/análise , Dieta/veterinária , Feminino , Haptoglobinas/metabolismo , Inflamação/prevenção & controle , Inflamação/veterinária , Lactação , Metionina/administração & dosagem , Paridade , Período Pós-Parto , Gravidez , Distribuição Aleatória
15.
Clin Nucl Med ; 45(3): 228-229, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31977460

RESUMO

Focal nodular fat sparing of the liver may show, on PET/CT imaging, prominent tracer uptake over a background of less metabolic features of steatosis. This finding, already reported with F-FDG, may mimic primary or secondary neoplasms of the liver. The authors present an additional case of nodular fat-sparing hepatic parenchyma exhibiting C-choline avidity during PET/CT assessment for biochemical recurrence of prostate cancer.


Assuntos
Tecido Adiposo/patologia , Radioisótopos de Carbono , Colina , Fígado/diagnóstico por imagem , Fígado/patologia , Tomografia Computadorizada com Tomografia por Emissão de Pósitrons , Idoso , Diagnóstico Diferencial , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias da Próstata/diagnóstico por imagem , Recidiva
16.
Phys Chem Chem Phys ; 22(6): 3490-3498, 2020 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-31990285

RESUMO

The liquid structures of six choline carboxylate/amino acid ionic liquids (bio-ILs) and their mixtures with water and various n-alkanols have been investigated by small-angle X-ray scattering (SAXS). The ILs exhibit long-range amphiphilic nanostructure comprised of polar and apolar domains that can be controlled by choice of anion, and which is tolerant to water dilution. Mixtures with n-alkanols can lead to marked changes in domain size and ordering. Utilising the Teubner-Strey model, we find amphiphilicity factors in many of these mixtures are comparable to those observed in conventional microemulsions, and that cooperative assembly in bio-IL/alkanol mixtures can enhance amphiphilicity, with potential to improve performance in a range of applications.


Assuntos
Aminoácidos/química , Ácidos Carboxílicos/química , Colina/química , Líquidos Iônicos/química , Nanoestruturas/química , Tensoativos/química
17.
Pest Manag Sci ; 76(3): 1142-1153, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31583806

RESUMO

BACKGROUND: Spirodiclofen is an acaricide that targets lipid biosynthesis by inhibiting acetyl-coenzyme A carboxylase. Spirodiclofen resistance in spider mites has been previously documented and was associated with overexpression of CYP392E10, a cytochrome P450 mono-oxygenase that metabolizes spirodiclofen. However, additional mechanisms have been suggested in several studies and a carboxyl/choline esterase gene, CCE04, was shown to be overexpressed in two genetically different strains, SR-VP and SR-TK, both exhibiting high spirodiclofen resistance levels. RESULTS: We identified two different CCE04 alleles in both resistant strains, CCE04SR-VP and CCE04London , with CCE04SR-VP being highly overexpressed. Isoelectric focusing analysis confirmed the overexpression of a single esterase isozyme, while copy number and random fragment length polymorphism analysis revealed that CCE04SR-VP overexpression was more likely due to selection for the CCE04SR-VP allele rather than gene amplification. Both CCE04 alleles were functionally expressed using the Pichia expression system. Functional enzyme assays revealed only limited kinetic differences between CCE04 isoforms for model substrates. In addition, inhibition/competition experiments with spirodiclofen suggested a similar interaction with both enzymes, whereas its active metabolite, spirodiclofen enol, did not inhibit enzyme activity. CONCLUSION: Our study suggests that selection with spirodiclofen results in enrichment of a specific allele of CCE04 (CCE04SR-VP ) in two genetically independent strains, which is highly overexpressed. Based on kinetic enzyme data, however, quantitative rather than qualitative differences between CCE04SR-VP and CCE04London seem more likely to be involved in resistance. Our findings are discussed in the light of a possible spirodiclofen resistance mechanism, with sequestration of spirodiclofen by CCE04SR-VP being a likely hypothesis. © 2019 Society of Chemical Industry.


Assuntos
Acaricidas , Tetranychidae , 4-Butirolactona/análogos & derivados , Alelos , Animais , Colina , Esterases , Compostos de Espiro
18.
Biochim Biophys Acta Biomembr ; 1862(2): 183115, 2020 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-31704086

RESUMO

The cell membrane is mainly composed of lipid bilayers with inserted proteins and carbohydrates. Lipid bilayers made of purified or synthetic lipids are widely used for estimating the effect of target compounds on cell membranes. However, the composition of such biomimetic membranes is much simpler than the composition of biological membranes. Interactions between compounds and simple composition biomimetic membranes might not demonstrate the effect of target compounds as precisely as membranes with compositions close to real organisms. Therefore, the aim of our study is to construct biomimetic membrane closely mimicking the state of natural membranes. Liposomes were prepared from lipids extracted from L-α-phosphatidylcholine, Escherichia coli, yeast (Saccharomyces cerevisiae) and bovine liver cells through agitation and sonication. They were immobilized onto silicon dioxide (SiO2) sensor surfaces using N-(2-hydroxyethyl)piperazine-N'-2-ethanesulfonic acid buffer with calcium chloride. The biomimetic membranes were successfully immobilized onto the SiO2 sensor surface and detected by nanoplasmonic sensing. The immobilized membranes were exposed to choline carboxylates. The membrane disruption effect was, as expected, more pronounced with increasing carbohydrate chain length of the carboxylates. The results correlated with the toxicity values determined using Vibrio fischeri bacteria. The yeast extracted lipid membranes had the strongest response to introduction of choline laurate while the bovine liver lipid extracted liposomes were the most sensitive towards the shorter choline carboxylates. This implies that the composition of the cell membrane plays a crucial role upon interaction with choline carboxylates, and underlines the necessity of testing membrane systems of different origin to obtain an overall image of such interactions.


Assuntos
Materiais Biomiméticos/química , Colina/análogos & derivados , Lipossomos/química , Lipídeos de Membrana/química , Animais , Bovinos , Membrana Celular/química , Saccharomyces cerevisiae
19.
Biosci Biotechnol Biochem ; 84(2): 380-392, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31608790

RESUMO

Plasmenylethonoamine (pPE) and plasmanylcholine (aPC) are important phospholipid subclasses. Herein we explored optimum conditions for enzymatic purification and preparation of pPE and aPC from the mussel Mytilus edulis and bovine brain. Among them, pPE in Mytilus edulis PE was mainly p18:0-20:5 and p18:0-22:6, and its purity was 92.7%; aPC in PC was primarily a16:0-22:6 and a16:0-20:5, and aPC accounted for 90.2% of PC. We thereafter evaluated neurotrophic effects of Mytilus edulis pPE, aPC, and bovine brain pPE in a NGF-induced PC12 cell model. Morphologically, pPE and aPC could both promote differentiation, manifested in a significant increase in neurite length and number, due to increased expression of synaptophysin and growth protein GAP-43 in a dose-independent and structure-selective manner. Importantly, the effect on neuronal nutrition of pPE was better than aPC, and marine pPE was better than terrestrial pPE, which might be ascribed to vinyl-ether bond and differences in fatty acid composition.Abbreviations: AA: arachidonic acid; DHA: docosahexaenoic acid; EIC: extracted ion chromatogram; EPA: eicosapentanoic acid; GAP: growth-associated protein; HPLC: high-performance liquid chromatography; LC-MS/MS: liquid chromatography-tandem mass spectrometry; LPC: lyso-PC; LPE: lyso-PE; MS: mass spectrometry; NGF: nerve growth factor; PC: phosphatidylcholine; aPC: plasmanylcholine; PE: phosphatidylethanolamine; pPE: plasmenylethonoamine; PG: phosphoglycerols; PLs: phospholipids; PS: phosphoserines; TIC: total ion chromatogram.


Assuntos
Colina/metabolismo , Mytilus edulis/metabolismo , Neurônios/metabolismo , Plasmalogênios/metabolismo , Animais , Encéfalo/metabolismo , Bovinos , Diferenciação Celular , Colina/administração & dosagem , Alimento Funcional , Proteína GAP-43/metabolismo , Neuritos , Células PC12 , Plasmalogênios/administração & dosagem , Ratos , Sinaptofisina/metabolismo
20.
Toxicol Lett ; 321: 21-31, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31830555

RESUMO

Nerve agents inhibit acetylcholinesterase (AChE), leading to a build-up of acetylcholine (ACh) and overstimulation at cholinergic synapses. Current post-exposure nerve agent treatment includes atropine to treat overstimulation at muscarinic synapses, a benzodiazepine anti-convulsant, and an oxime to restore the function of AChE. Aside from the oxime, the components do not act directly to reduce the overstimulation at nicotinic synapses. The false transmitters acetylmonoethylcholine (AMECh) and acetyldiethylcholine (ADECh) are analogs of ACh, synthesised similarly at synapses. AMECh and ADECh are partial agonists, with reduced activity compared to ACh, so it was hypothesised the false transmitters could reduce overstimulation. Synthetic routes to AMECh and ADECh, and their precursors, monoethylcholine (MECh) and diethylcholine (DECh), were devised, allowing them to be produced easily on a laboratory-scale. The mechanism of action of the false transmitters was investigated in vitro. AMECh acted as a partial agonist at human muscarinic (M1 and M3) and muscle-type nicotinic receptors, and ADECh was a partial agonist only at certain muscarinic subtypes. Their precursors acted as antagonists at muscle-type nicotinic, but not muscarinic receptors. Administration of MECh and DECh improved neuromuscular function in the soman-exposed guinea-pig hemi-diaphragm preparation. False transmitters may therefore help reduce nerve agent induced overstimulation at cholinergic synapses.


Assuntos
Acetilcolina/análogos & derivados , Antídotos/farmacologia , Colina/análogos & derivados , Inibidores da Colinesterase/envenenamento , Diafragma/inervação , Agentes Neurotóxicos/envenenamento , Neurotransmissores/farmacologia , Intoxicação por Organofosfatos/tratamento farmacológico , Soman/envenenamento , Sinapses/efeitos dos fármacos , Acetilcolina/síntese química , Acetilcolina/metabolismo , Acetilcolina/farmacologia , Acetilcolinesterase/metabolismo , Animais , Antídotos/síntese química , Células CHO , Linhagem Celular Tumoral , Colina/síntese química , Colina/farmacologia , Cricetulus , Agonismo Parcial de Drogas , Cobaias , Humanos , Masculino , Neurotransmissores/síntese química , Intoxicação por Organofosfatos/enzimologia , Intoxicação por Organofosfatos/fisiopatologia , Receptores Colinérgicos/efeitos dos fármacos , Receptores Colinérgicos/genética , Receptores Colinérgicos/metabolismo , Sinapses/enzimologia
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