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1.
Anticancer Res ; 40(1): 253-259, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31892574

RESUMO

BACKGROUND/AIM: The aim of the study was to compare the MDA (malonidialdehyde) plasma concentrations versus CAT (catalase)/NT (nitrotyrosine) plasma concentrations, patient satisfaction and pain score at rest/pressure to the wound area in laparotomy patients with rectus sheath block (RSB) analgesia. PATIENTS AND METHODS: Initially, 56 patients were randomized to four groups; control group (n=12), single-dose (n=16), repeated-dose (n=12) and continuous infusion (n=16) RSB analgesia groups. The plasma concentrations of CAT, NT and MDA markers were measured just before, immediately after and 24 h after operation. RESULTS: The RSB analgesia enhanced significantly patient satisfaction (p=0.001). The plasma MDA decreased immediately after operation (POP1) and the postoperative decrease between the preoperative and the POP1 values in the MDA marker were statistically significant (p<0.001). In linear mixed model, the time effect in both the single group and in the benign group in plasma NT biomarker was statistically significant (p=0.001, p=0.013, respectively). The median plasma MDA concentrations (ng/ml) following surgery were significantly lower in patients with cancer versus patients with benign disease (589 vs. 852, p=0.021). Jitterplots of the individual plasma NT versus plasma MDA showed that there was significant correlation in benign and cancer patients (r=0.347, p<0.001). CONCLUSION: Plasma MDA decreased significantly after operation in all patients and cancer patients had significantly lower MDA concentrations following surgery than patients with benign disease.


Assuntos
Analgesia , Laparotomia , Malondialdeído/sangue , Neoplasias/sangue , Bloqueio Nervoso , Catalase/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tirosina/análogos & derivados , Tirosina/sangue
2.
Medicina (Kaunas) ; 55(5)2019 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-31126140

RESUMO

Background and objective: One of the reasons for thrombosis in chronic heart failure (CHF) might be reactive forms of oxygen activating platelets. The aim of this study was to evaluate the effect of oxidant hypochlorous acid (HOCl) on platelet aggregation and dityrosine concentration in CHF patients and healthy controls. Materials and Methods: CHF patients (n 67) and healthy (n 31) were investigated. Heart echoscopy, 6-min walking test, complete blood count, platelet aggregation, and dityrosine concentration were performed. Platelet aggregation and dityrosine concentration were measured in plasma samples after incubation with different HOCl concentrations (0.15, 0.0778, and 0.0389 mmol/L). Results: Platelet aggregation without oxidant was lower (p = 0.049) in CHF patients than in controls. The spontaneous platelet aggregation with oxidant added was higher in CHF patients (p = 0.004). Dityrosine concentration was also higher (p = 0.032) in CHF patients. Platelet aggregation was the highest in samples with the highest oxidant concentration in both healthy controls (p = 0.0006) and in CHF patients (p = 0.036). Platelet aggregation was higher in NYHA III group in comparison to NYHA II group (p = 0.0014). Concentration of dityrosine was significantly higher in CHF samples (p = 0.032). The highest concentration of dityrosine was obtained in NYHA IV group samples (p 0.05). Intensity of platelet aggregation, analyzed with ADP, was correlated with LV EF (r 0.42, p = 0.007). Dityrosine concentration was correlated with NYHA functional class (r 0.27, p 0.05). Conclusions: The increase in platelet aggregation in CHF and healthy controls shows the oxidant effect on platelets. The increase in dityrosine concentration in higher NYHA functional classes shows a higher oxidative stress in patients with worse condition.


Assuntos
Insuficiência Cardíaca/sangue , Ácido Hipocloroso/uso terapêutico , Agregação Plaquetária/fisiologia , Tirosina/análogos & derivados , Idoso , Feminino , Voluntários Saudáveis , Insuficiência Cardíaca/enzimologia , Insuficiência Cardíaca/fisiopatologia , Humanos , Ácido Hipocloroso/farmacocinética , Masculino , Pessoa de Meia-Idade , Estatísticas não Paramétricas , Tirosina/análise , Tirosina/sangue
3.
Anticancer Res ; 39(3): 1383-1389, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30842172

RESUMO

BACKGROUND/AIM: Our hypothesis was that rectus sheath block (RSB) analgesia could enhance satisfaction following midline laparotomy in patients with benign disease and cancer patients. PATIENTS AND METHODS: Initially, 56 patients were randomized into four groups; control group (n=12), single-dose (n=16), repeated-dose (n=12) and continuous infusion (n=16) RSB analgesia groups. The plasma concentrations of the NT marker were measured just before, immediately after and 24 h after operation. Patient satisfaction at 24 h postoperatively was filed on a 11-point numeric rating scale (SFS24; 0=fully unsatisfied; 10=fully satisfied). RESULTS: The RSB analgesia significantly enhanced the SFS24 scores in the study groups (p=0.001). The median plasma NT concentrations (pg/ml) following surgery (POP1) were significantly lower in patients with cancer versus patients with benign disease (5.3 vs. 7.6, p=0.008). Jitter plots of the individual SFS24 values versus plasma NT concentrations were significantly correlated in benign and cancer patients (r=-0.284, p=0.028). CONCLUSION: The RSB analgesia could significantly enhance patient satisfaction following midline laparotomy. Plasma NT concentrations versus patient satisfaction following surgery are significantly correlated in benign disease and cancer.


Assuntos
Neoplasias/cirurgia , Bloqueio Nervoso , Reto do Abdome , Tirosina/análogos & derivados , Idoso , Analgesia , Feminino , Humanos , Laparotomia , Masculino , Pessoa de Meia-Idade , Neoplasias/sangue , Estresse Nitrosativo , Tirosina/sangue
4.
Nutrients ; 11(3)2019 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-30823411

RESUMO

Introduction: In phenylketonuria (PKU), evidence suggests that casein glycomacropeptide supplemented with rate-limiting amino acids (CGMP-AA) is associated with better protein utilisation and less blood phenylalanine (Phe) variability. Aim: To study the impact of CGMP-AA on blood Phe variability using 3 different dietary regimens in children with PKU. Methods: This was a 6-week randomised controlled cross-over study comparing CGMP-AA vs. Phe-free l-amino acids (l-AA) assessing blood Phe and tyrosine (Tyr) variability over 24 h in 19 children (7 boys) with PKU, with a median age of 10 years (6⁻16). Subjects were randomised to 3 dietary regimens: (1) R1, CGMP-AA and usual dietary Phe (CGMP + Phe); (2) R2, CGMP-AA - Phe content of CGMP-AA from usual diet (CGMP - Phe); and (3) R3, l-AA and usual dietary Phe. Each regimen was administered for 14 days. Over the last 48 h on days 13 and 14, blood spots were collected every 4 h at 08 h, 12 h, 16 h, 20 h, 24 h, and 04 h. Isocaloric intake and the same meal plan and protein substitute dosage at standardised times were maintained when blood spots were collected. Results: Eighteen children completed the study. Median Phe concentrations over 24 h for each group were (range) R1, 290 (30⁻580), R2, 220 (10⁻670), R3, 165 (10⁻640) µmol/L. R1 vs. R2 and R1 vs. R3 p < 0.0001; R2 vs. R3 p = 0.0009. There was a significant difference in median Phe at each time point between R1 vs. R2, p = 0.0027 and R1 vs. R3, p < 0.0001, but not between any time points for R2 vs. R3. Tyr was significantly higher in both R1 and R2 [70 (20⁻240 µmol/L] compared to R3 [60 (10⁻200) µmol/L]. In children < 12 years, blood Phe remained in the target range (120⁻360 µmol/L), over 24 h, for 75% of the time in R1, 72% in R2 and 64% in R3; for children aged ≥ 12 years, blood Phe was in target range (120⁻600 µmol/L) in R1 and R2 for 100% of the time, but 64% in R3. Conclusions: The residual Phe in CGMP-AA increased blood Phe concentration in children. CGMP-AA appears to give less blood Phe variability compared to l-AA, but this effect may be masked by the increased blood Phe concentrations associated with its Phe contribution. Reducing dietary Phe intake to compensate for CGMP-AA Phe content may help.


Assuntos
Caseínas/administração & dosagem , Caseínas/farmacologia , Fragmentos de Peptídeos/administração & dosagem , Fragmentos de Peptídeos/farmacologia , Fenilalanina/sangue , Tirosina/sangue , Criança , Suplementos Nutricionais , Feminino , Humanos , Masculino , Fenilalanina/metabolismo , Fenilcetonúrias , Tirosina/metabolismo
5.
Mater Sci Eng C Mater Biol Appl ; 98: 496-502, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30813051

RESUMO

Electrochemical oxidation of l­cysteine resulted in the formation of a film on glassy carbon electrode. In a solution of levodopa (l­DOPA), l­tyrosine (Tyr) and uric acid (UA), three separated intense anodic peaks were appeared in differential pulse voltammetry regime. Experimental conditions were optimized for simultaneous determination of the three compounds. All experiments were carried out in phosphate buffer solution (0.1 M, pH 8). Calibration curves were obtained in the presence of various concentrations of l­DOPA, Tyr, and UA. Linear concentration ranges were 0.65-22 µM for l­DOPA, 3.5-96 µM for Tyr, and 1.0-19 µM for UA. The limits of detection (LODs) were calculated as 0.2, 1.1 and 0.36 µM for l­DOPA, Tyr, and UA, respectively. The electrochemical sensor was used successfully for the simultaneous determination of l­DOPA, Tyr, and UA species in human blood serum samples.


Assuntos
Carbono/química , Ácido Cisteico/química , Vidro/química , Levodopa/sangue , Tirosina/sangue , Ácido Úrico/sangue , Técnicas Eletroquímicas , Eletrodos , Humanos , Concentração de Íons de Hidrogênio , Polimerização
6.
Clin Chim Acta ; 494: 100-105, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30904545

RESUMO

BACKGROUND: Availability of appropriately established reference intervals for biochemical tests can be troublesome in pediatrics. Here we establish age-specific continuous reference intervals for catecholamine O-methylated metabolites in children evaluated for catecholamine producing tumors, particularly younger children with suspected neuroblastoma. METHODS: Plasma concentrations of 3-methoxytyramine, normetanephrine, metanephrine, and 3-O-methyldopa were analyzed by liquid chromatography tandem mass spectrometry in 533 children aged 2 days to 18 years. RESULTS: Concentrations of plasma free normetanephrine, 3-methoxytyramine and 3-O-methyldopa were higher in neonates up until six months of age, but thereafter declined steeply to levels after one year that were <38% those of neonatal concentrations and to further lower concentrations in teenagers that were <23% those in neonates. In contrast, concentrations of plasma free metanephrine showed a reciprocal pattern with 50% lower concentrations in infants below one year compared to later in childhood. CONCLUSION: The dynamic reciprocal changes in plasma concentrations of normetanephrine, 3-methoxytyramine and 3-O-methyldopa compared to metanephrine during early childhood suggest underlying developmental changes in extra-adrenal and adrenal chromaffin tissue that must be considered for pediatric reference intervals, particularly in infants. With such reference intervals at hand, biochemical testing for catecholamine producing tumors in young children is substantially improved.


Assuntos
Neoplasias das Glândulas Suprarrenais/sangue , Envelhecimento/sangue , Dopamina/análogos & derivados , Metanefrina/sangue , Normetanefrina/sangue , Paraganglioma/sangue , Feocromocitoma/sangue , Tirosina/análogos & derivados , Adolescente , Análise Química do Sangue , Catecolaminas/biossíntese , Criança , Pré-Escolar , Cromatografia Líquida , Dopamina/sangue , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Valores de Referência , Espectrometria de Massas em Tandem , Tirosina/sangue
7.
Anticancer Res ; 39(2): 809-814, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30711961

RESUMO

BACKGROUND/AIM: The aim of this study was to assess the plasma concentration of the nitrosative stress biomarker nitrotyrosine (NT) in gallstone disease and cancer patients. MATERIALS AND METHODS: Initially, 114 patients with symptomatic gallstone disease were randomized into the laparoscopic cholecystectomy (LC) (n=54) and the minicholecystectomy (MC) (n=60) groups. The plasma concentrations of NT were measured just before, immediately after (POP1) and 6 h after operation (POP2). The cancer patients of this study included ten patients with gastrointestinal cancer and 19 patients with gynecological cancer. RESULTS: There was a statistically significant correlation in the median plasma NT concentrations versus plasma catalase (CAT) concentrations in cholecystectomy patients (r=0.169, p=0.001). Interestingly, there was a statistically significant inverse correlation between the individual values of the pain assessed and filed using a 11-point numeric rating scale 8 h postoperatively (NAD8) and plasma NT median values in cholecystectomy patients (r=-0.337, p=0.004). CONCLUSION: Patients with high plasma concentrations of NT appeared to have significantly lower pain scores 8 h postoperatively.


Assuntos
Biomarcadores/sangue , Cálculos Biliares/sangue , Neoplasias Gastrointestinais/sangue , Neoplasias dos Genitais Femininos/sangue , Tirosina/análogos & derivados , Adulto , Idoso , Colecistectomia Laparoscópica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estresse Nitrosativo , Manejo da Dor , Medição da Dor , Período Pós-Operatório , Espécies Reativas de Oxigênio/sangue , Tirosina/sangue
8.
Anim Sci J ; 90(4): 533-538, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30773747

RESUMO

The aim of this study was to evaluate the effect of feeding decoction of a traditional nourishing Chinese herbal medicine formula on rates of plasma phenylalanine and tyrosine turnover and whole body protein synthesis in sheep. Ruminal fermentation characteristics and blood metabolites were also determined. Six sheep were subjected to either mixed hay (MH-diet, as control) or MH-diet supplemented with 2% of Chinese herbal medicine (mixture of Astragalus root, Angelica root, and Atractylodes rhizome; CHM-diet) in a crossover design for each of 3-week period. The isotope dilution of [2 H5 ]phenylalanine and [2 H2 ]tyrosine was performed as a primed-continuous infusion to measure plasma phenylalanine and tyrosine kinetics. Concentrations of total volatile fatty acid, acetate, and propionate in the rumen tended to be higher (p < 0.10), and the pH value was lower (p = 0.04) for the CHM-diet than the MH-diet. Turnover rates of plasma phenylalanine and tyrosine tended to be higher (p < 0.10) for the CHM-diet than the MH-diet. Furthermore, whole body protein synthesis was greater (p = 0.04) for the CHM-diet compared with the MH-diet. The Chinese herbal medicine improved rumen fermentation and enhanced protein metabolism in sheep. Hence, it is suggested that the decoction of Chinese herbal medicine formula could be considered as a potential feed additive for ruminant production.


Assuntos
Dieta/veterinária , Medicamentos de Ervas Chinesas/farmacologia , Fenilalanina/sangue , Biossíntese de Proteínas/efeitos dos fármacos , Ovinos/sangue , Ovinos/metabolismo , Tirosina/sangue , Angelica , Animais , Astrágalo (Planta) , Atractylodes , Estudos Cross-Over , Fermentação/efeitos dos fármacos , Masculino , Rúmen/metabolismo
9.
J Pharm Biomed Anal ; 168: 30-37, 2019 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-30784887

RESUMO

Detection of amino acids (AAs) in blood is helpful to diagnose some diseases. In this work, a method is developed for determination of trace amounts of AAs in bovine blood by combining solid phase extraction (SPE) and capillary electrophoresis (CE). Zeolitic imidazolate framework-8 (ZIF-8) nanoparticles are prepared and used as adsorbents to simultaneously extract three AAs (tryptophan, tyrosine, phenylalanine). Under the optimum extraction conditions, the extraction efficiencies of ZIF-8 for AAs are 95.1% (tryptophan), 91.1% (tyrosine), and 90.1% (phenylalanine), respectively. Interestingly, ZIF-8 demonstrates good extraction ability for AAs in high concentration of acetonitrile (ACN) aqueous solutions. Thus, they can be directly used to extract AAs from the deproteinized blood sample using ACN. An α-cyclodextrin-mediated cation selective exhaustive injection-sweeping CE method is developed for analysis of the extracted AAs. The detection limits for AAs range from 0.13 to 0.37 µg mL-1 using the SPE/CE method. Standard addition method is used to evaluate the feasibility of the method in bovine blood samples. The standard addition curves demonstrate good linearity with determination coefficient > 0.9912.


Assuntos
Imidazóis/química , Fenilalanina/análise , Triptofano/análise , Tirosina/análise , Animais , Bovinos , Eletroforese Capilar/métodos , Limite de Detecção , Nanopartículas , Fenilalanina/sangue , Extração em Fase Sólida/métodos , Triptofano/sangue , Tirosina/sangue , Zeolitas/química
10.
Clin Biochem ; 66: 37-43, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30776353

RESUMO

INTRODUCTION: We aimed to analyze the association of nitrotyrosine (N-TYR) levels and long-term survival in an ongoing coronary heart disease (CHD) prospective cohort, the Acute Coronary Syndrome Registry Strategy (ERICO study). METHODS: N-TYR levels collected during acute and subacute phase from onset of acute coronary syndrome (ACS) symptoms (myocardial infarction and unstable angina) were evaluated in 342 patients. We calculated case-fatality rates (180-days, 1 year, 2 years and 4 years) and survival analyses up to 4 years using Kaplan-Meier curves and Cox regression with respective cumulative hazard ratios (95% confidence interval; 95%CI), according to N-TYR tertiles up to 4 years of follow-up. Models are presented as crude, age and sex-adjusted and further adjusted for lipids and other confounders. RESULTS: Overall, median level of N-TYR was 208.33 nmol/l (range: 3.09 to 1500 nmol/l), regardless ACS subtype. During follow-up of 4 years, we observed 44 (12.9%) deaths. Overall survival rate was 298 (87.1%) (Survival days: 1353, 95%CI: 1320-1387 days). N-TYR levels did not associate with mortality / survival rates up to 4 years. CONCLUSIONS: No relationship was found between N-TYR levels and mortality rates after ACS during 4-year follow-up in the ERICO study.


Assuntos
Síndrome Coronariana Aguda/diagnóstico , Doença das Coronárias/diagnóstico , Tirosina/análogos & derivados , Síndrome Coronariana Aguda/mortalidade , Idoso , Biomarcadores/sangue , Doença das Coronárias/mortalidade , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Fatores de Risco , Taxa de Sobrevida , Fatores de Tempo , Tirosina/sangue
11.
Eur Arch Otorhinolaryngol ; 276(4): 1197-1204, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30729295

RESUMO

OBJECTIVE: The purpose of this study was to determine the oxidative states of head and neck squamous cell carcinoma (HNSCC) patients by measuring their plasma levels of malondialdehyde (MDA), an indicator of lipid peroxidation, 3-nitrotyrosine (3-NT), an indicator of protein oxidation, and the coenzyme Q10 (CoQ10), an important antioxidant, and compare them with healthy individuals. MATERIALS AND METHODS: The plasma MDA, 3-NT and CoQ10 levels of 35 patients and 20 healthy individuals were measured with the high-performance liquid chromatography (HPLC) method. By comparing the patients' smoking habits, stage of the disease, size of the primary tumor and the presence of lymph nodes and the values of healthy individuals, the oxidative stress load of HNSCC patients was determined. RESULTS: The mean plasma MDA levels of carcinoma patients were two times higher than those of healthy individuals (p < 0.001). When the mean plasma 3-NT levels of patients and healthy individuals were compared, no significant difference was found (p > 0.05). The mean plasma CoQ10 level of patients was low when compared with healthy individuals; however, no significant difference was detected (p > 0.05). In addition, as the stage and tumor size increased in HNSCC patients, their non-enzymatic antioxidant levels significantly decreased (p < 0.05). CONCLUSIONS: In HNSCC patients, lipo-oxidative damage increased while nitrosative stress did not change; however, antioxidant activity decreased which in turn increased both lipid peroxidation and oxidative stress. These findings support the contention that oxidative stress strongly reflects the health status of HNSCC patients.


Assuntos
Neoplasias de Cabeça e Pescoço/sangue , Estresse Oxidativo/fisiologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/sangue , Ubiquinona/análogos & derivados , Adulto , Idoso , Idoso de 80 Anos ou mais , Antioxidantes/metabolismo , Estudos de Casos e Controles , Cromatografia Líquida de Alta Pressão , Feminino , Humanos , Peroxidação de Lipídeos , Masculino , Malondialdeído/sangue , Pessoa de Meia-Idade , Tirosina/análogos & derivados , Tirosina/sangue , Ubiquinona/sangue
12.
Niger J Clin Pract ; 22(2): 174-180, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30729939

RESUMO

Introduction: Oxidative stress has been associated with primary dysmenorrhea, but studies that have assessed multiple markers of peroxidation are scarce. This study investigated malondialdehyde (MDA), nitrotyrosine (3-NT), and protein carbonyls (PrCarb) as markers of oxidative stress and antioxidant status by serum alpha tocopherol level in young Nigerian women with dysmenorrhea. Materials and Methods: In a case-control design, 45 female undergraduates who had had regular menses for at least six previous cycles were recruited consecutively from a university clinic as cases and 45 apparently healthy age-matched counterparts in their hall of residences as controls. Serum levels of MDA, 3-NT, and PrCarb were determined using standard methods, and the values were compared between cases and controls using Mann-Whitney U-test and graphs. Results: Study participants' ages range from 16 to 29 years (mean = 22.0 ± 3.1 years). Serum level of 3-NT (45.89 ± 37.11 vs 21.27 ± 13.94 ng/mL) and MDA (0.75 ± 0.19 vs 0.45 ± 0.11 nmol/mL) was significantly higher in cases than controls. Plasma alpha tocopherol was significantly lower in cases (7.51 ± 1.95 µmol/L) than controls (8.98 ± 1.95 µmol/L). Conversely, PrCarb levels were not significantly difference between cases and controls. There were significant correlations between alpha tocopherol and 3-NT (r = -0.285; P = 0.007) and MDA (r = -0.321; P = 0.002), whereas this relationship was not shown with PrCarb (r = -0.073; P = 0.496). Conclusion: Remarkable lipid and protein peroxidation observed in young Nigerian women with dysmenorrhea was accompanied by correspondingly low level of serum alpha tocopherol suggesting potential need for vitamin E supplementation.


Assuntos
Dismenorreia/sangue , Peroxidação de Lipídeos , Malondialdeído/sangue , Estresse Oxidativo , Tirosina/análogos & derivados , alfa-Tocoferol/sangue , Adolescente , Adulto , Antioxidantes/metabolismo , Biomarcadores/sangue , Estudos de Casos e Controles , Feminino , Humanos , Lipídeos , Masculino , Estudantes/estatística & dados numéricos , Tirosina/sangue , Adulto Jovem
13.
Artigo em Inglês | MEDLINE | ID: mdl-30278308

RESUMO

In this contribution, a new highly sensitive and selective sensor of the determination of tyrosine has been proposed based on the downturn effect of light scattering (LS) using phosphodiesters quaternary ammonium nanoparticles (PQANPs). Phosphodiesters quaternary ammonium (PQA), one of Gemini zwitterionic surfactants, self-aggregated into the micelle named as PQANPs, which generated strong LS signal in aqueous solution under the optimum condition. Interestingly, the powerful LS intensity of PQANPs with the maximum peak located at 391 nm significantly decreased after introducing trace amount of tyrosine. The decreased value of the LS intensity of the PQA-tyrosine system (ΔILS) was in proportion to tyrosine concentration in the ranges from 5.5 × 10-8 mol/L to 4.68 × 10-6 mol/L, with a detection limit of 1.38 × 10-8 mol/L. Based on this decreased LS situation, the novel approach of the determination of tyrosine was first developed. The reaction mechanism for the interaction between PQANPs and tyrosine was also investigated. Moreover, the proposed LS assay was applied to the detection of tyrosine concentration in human serum and urine samples with satisfactory results.


Assuntos
Luz , Nanopartículas/química , Organofosfatos/química , Compostos de Amônio Quaternário/química , Espalhamento de Radiação , Tirosina/sangue , Tirosina/urina , Humanos , Concentração de Íons de Hidrogênio , Nanopartículas/ultraestrutura
14.
J Diabetes Investig ; 10(2): 491-498, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29999591

RESUMO

AIMS/INTRODUCTION: Metabolomic markers have the potential to improve the predicting accuracy of existing risk scores for type 2 diabetes mellitus. The present study aimed to test the associations between plasma tyrosine and type 2 diabetes mellitus with special attention to identifying possible cut-off points for type 2 diabetes mellitus, and its interactive effects with low high-density lipoprotein cholesterol (HDL-C) and/or high triglyceride for type 2 diabetes mellitus. METHODS: From 27 May 2015 to 3 August 2016, we retrieved the medical notes of 1,898 inpatients with type 2 diabetes mellitus as the cases, and 1,522 individuals without diabetes as the controls who attended annual medical checkups from the same tertiary care center in Jinzhou, China. Logistic regression analyses were carried out to obtain odds ratios (ORs) and 95% confidence intervals (CIs). Restricted cubic spline analysis nested in the logistic regression analysis was used to identify possible cut-off points of tyrosine for type 2 diabetes mellitus. The additive interaction was used to estimate interactions between high tyrosine and low HDL-C in type 2 diabetes mellitus patients. RESULTS: The OR of tyrosine for type 2 diabetes mellitus did not increase until 46 µmol/L and after that point, the OR rapidly rose with increasing tyrosine in a nearly linear manner. If 46 µmol/L was used to define high tyrosine, high tyrosine was associated with an increased OR of type 2 diabetes mellitus (adjusted OR 1.88, 95% CI 1.44-2.45). The presence of low HDL-C greatly enhanced the ORs of tyrosine for type 2 diabetes mellitus from 1.11 (95% CI 0.82-1.51) to 54.11 (95% CI 33.96-86.22) with significant additive interaction. CONCLUSIONS: In Chinese adults, tyrosine >46 µmol/L was associated with increased odds of type 2 diabetes mellitus, which was contingent on low HDL-C.


Assuntos
Grupo com Ancestrais do Continente Asiático/estatística & dados numéricos , Biomarcadores/sangue , HDL-Colesterol/sangue , Diabetes Mellitus Tipo 2/diagnóstico , Tirosina/sangue , Estudos de Casos e Controles , Estudos Transversais , Diabetes Mellitus Tipo 2/sangue , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Curva ROC , Fatores de Risco
15.
J Obstet Gynaecol ; 39(1): 17-21, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29884105

RESUMO

The purpose of this prospective study was to investigate the changes in the circulating levels of cathepsin B and D in pregnancy. We obtained longitudinal cathepsin B and D levels in 76 healthy pregnant women in the first and third trimesters and compared these levels with 20 non-pregnant controls. The plasma levels of soluble cathepsin B and D were measured using an enzyme-linked immunosorbent assay kit. The cathepsin D concentrations in the third trimester were significantly higher than that in the first trimester (p < .001), and the cathepsin D levels in the first trimester were significantly lower than that in the non-pregnant controls (p = .002). However, there was no significant difference in the cathepsin B level throughout pregnancy compared to the non-pregnant controls. Our study is unique in evaluating the longitudinal changes in the cathepsin B and D levels in pregnancies without obstetric complications. The results implicate that changes in the levels of cathepsins might be essential in placentation. Therefore, molecular and genetic studies on cathepsin B and D are needed to understand the roles of these enzymes in pregnancy, thereby contributing to the understanding of placentation. Impact statement What is already known? Matrix metalloproteinases (MMP) have been widely studied, and their function is very important in the normal implantation process. The level of MMP-9 is known to increase throughout pregnancy, while the level of MMP-2 decreases in the first trimester. In addition to MMPs, other proteases are important for placental development; cathepsins B and D are two of the proteases that are involved in the normal placentation process. The function of cathepsin D is related to MMPs because this protease can activate MMPs either directly or indirectly. Nevertheless, the role of circulating cathepsins in pregnancy has not yet been fully elucidated. What do these results add? This study provides evidence, for the first time, that there are fluctuations of plasma cathepsin D level and there are no changes in the plasma cathepsin B level in a normal pregnancy. Moreover, we demonstrated that a cathepsin D level is significantly decreased in the first trimester compared to the non-pregnant controls, and that the level is markedly elevated in the third trimester. What are the implications of these findings for clinical practice and/or further research? Cathepsins B and D should be further studied locally in the placenta to explain the differences in the concentration of cathepsin D and no changes in cathepsin B, thereby exploring their exact roles.


Assuntos
Catepsina C/sangue , Compostos de Epóxi/sangue , Placentação , Gravidez/sangue , Tirosina/análogos & derivados , Adulto , Estudos de Casos e Controles , Gonadotropina Coriônica/sangue , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Primeiro Trimestre da Gravidez/sangue , Terceiro Trimestre da Gravidez/sangue , Proteína Plasmática A Associada à Gravidez/análise , Estudos Prospectivos , Tirosina/sangue
16.
Nutrients ; 10(11)2018 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-30453665

RESUMO

In phenylketonuria (PKU), synthetic protein derived from L-amino acids (AAs) is essential in a low-phenylalanine (Phe) diet. Glycomacropeptide (GMP), an intact protein, is very low in Phe in its native form. It has been modified and adapted for PKU to provide an alternative protein source through supplementation with rate-limiting amino acids (GMP-AAs), although it still contains residual Phe. This review aims to systematically evaluate published intervention studies on the use of GMP-AAs in PKU by considering its impact on blood Phe control (primary aim) and changes in tyrosine control, nutritional biomarkers, and patient acceptability or palatability (secondary aims). Four electronic databases were searched for articles published from 2007 to June 2018. Of the 274 studies identified, only eight were included. Bias risk was assessed and a quality appraisal of the body of evidence was completed. A meta-analysis was performed with two studies with adequate comparable methodology which showed no differences between GMP-AAs and AAs for any of the interventions analysed. This work underlines the scarcity and nature of studies with GMP-AAs interventions. All were short-term with small sample sizes. There is a need for better-designed studies to provide the best evidence-based recommendations.


Assuntos
Caseínas/administração & dosagem , Dieta com Restrição de Proteínas/métodos , Suplementos Nutricionais , Fragmentos de Peptídeos/administração & dosagem , Fenilcetonúrias/dietoterapia , Aminoácidos/sangue , Humanos , Fenilalanina/sangue , Fenilcetonúrias/sangue , Tirosina/sangue
17.
Invest Ophthalmol Vis Sci ; 59(12): 4945-4952, 2018 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-30347088

RESUMO

Purpose: Oral nitisinone has been shown to increase fur and ocular pigmentation in a mouse model of oculocutaneous albinism (OCA) due to hypomorphic mutations in tyrosinase (TYR), OCA1B. This study determines if nitisinone can improve ocular and/or fur pigmentation in a mouse model of OCA type 3 (OCA3), caused by mutation of the tyrosinase-related protein 1 (Tyrp1) gene. Methods: Mice homozygous for a null allele in the Tyrp1 gene (C57BL/6J-Tyrp1 b-J/J) were treated with 8 mg/kg nitisinone or vehicle every other day by oral gavage. Changes in fur and ocular melanin pigmentation were monitored. Mature ocular melanosome number and size were quantified in pigmented ocular structures by electron microscopy. Results: C57BL/6J-Tyrp1 b-J/J mice carry a novel c.403T>A; 404delG mutation in Tyrp1, predicted to result in premature truncation of the TYRP1 protein. Nitisinone treatment resulted in an approximately 7-fold increase in plasma tyrosine concentrations without overt toxicity. After 1 month of treatment, no change in the color of fur or pigmented ocular structures was observed. The distribution of melanosome cross-sectional area was unchanged in ocular tissues. There was no significant difference in the number of pigmented melanosomes in the RPE/choroid of nitisinone-treated and control groups. However, there was a significant difference in the number of pigmented melanosomes in the iris. Conclusions: Treatment of a mouse model of OCA3 with oral nitisinone did not have a favorable clinical effect on melanin production and minimally affected the number of pigmented melanosomes in the iris stroma. As such, treatment of OCA3 patients with nitisinone is unlikely to be therapeutic.


Assuntos
Albinismo Oculocutâneo/tratamento farmacológico , Cicloexanonas/uso terapêutico , Inibidores Enzimáticos/uso terapêutico , Nitrobenzoatos/uso terapêutico , Administração Oral , Albinismo Oculocutâneo/sangue , Albinismo Oculocutâneo/genética , Albinismo Oculocutâneo/patologia , Animais , Western Blotting , Modelos Animais de Doenças , Técnicas de Genotipagem , Melaninas/metabolismo , Melanossomas/patologia , Glicoproteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , Microscopia Eletrônica de Transmissão , Oxirredutases/genética , Reação em Cadeia da Polimerase em Tempo Real , Resultado do Tratamento , Tirosina/sangue
18.
J Occup Environ Med ; 60(12): 1073-1081, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30188494

RESUMO

OBJECTIVES: The current laboratory study quantified blood oxidative stress to woodsmoke exposure. METHODS: Participants inhaled woodsmoke during three randomized crossover exercise trials (Clean Air [0 µg/m], Low Exposure [250 µg/m], and High Exposure [500 µg/m], Woodsmoke [particulate matter less than 2.5 µm, PM2.5]). Trolox equivalent antioxidant capacity (TEAC), uric acid (UA), 8-isoprostanes (8-ISO), lipid hydroperoxides (LOOH), protein carbonyls (PC), nitrotyrosine (3-NT), 8-isoprostane, and myeloperoxidase (MPO) were quantified in Pre, immediately Post, and 1- (1Hr) hour post blood samples. RESULTS: UA decreased following Low Exposure, while plasma TEAC levels increased Post and 1Hr. LOOH levels decreased 1Hr Post (High Exposure), while 8-Iso increased following both smoke trials. PC and MPO were unchanged following all trials, while 3-NT increased over Clean Air. CONCLUSION: Blood oxidative stress occurred largely independent of PM2.5 concentrations. Future studies should employ longer duration smoke and exercise combined with physiologic parameters.


Assuntos
Exposição por Inalação/efeitos adversos , Estresse Oxidativo , Esforço Físico , Fumaça/efeitos adversos , Adulto , Antioxidantes , Estudos Cross-Over , Dinoprosta/análogos & derivados , Dinoprosta/sangue , Teste de Esforço , Humanos , Isoprostanos/sangue , Peróxidos Lipídicos/sangue , Material Particulado/efeitos adversos , Peroxidase/sangue , Carbonilação Proteica , Distribuição Aleatória , Tirosina/análogos & derivados , Tirosina/sangue , Ácido Úrico/sangue , Incêndios Florestais , Madeira , Adulto Jovem
19.
Anal Biochem ; 558: 12-18, 2018 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-30076789

RESUMO

Here, we aimed to use graphene oxide to improve the selectivity and sensitivity of Tyr determination via the reaction with 1-nitroso-2-naphthol as a selective reagent of Tyr. The reaction between Tyr and 1-nitroso-2-naphthol in absence and presence of GO was studied spectrophotometrically. Different parameters such as concentrations, temperature, incubation time were optimized. The obtained data showed that the maximum absorbance was achieved by using 2 mL of 0.03% 1-nitroso-2-naphthol at temperature 60 °C for 10 min. On the basis of calibration curve of various concentrations of Tyr in the presence of 20 µg mL-1 GO, the limit of detection was 6.4 × 10-6 M (1.15 µg mL-1), where in absence of GO was 1.1 × 10-5 M (19.9 µg mL-1). The selectivity of Tyr in presence of other amino acids and phenols was studied with and without GO. The data obtained revealed that the selectivity of Tyr in presence of GO with respect to some amino acids and phenols was improved. The proposed method has been applied for the determination of Tyr in urine and serum samples. Therefore, GO is a powerful catalytic surface for the sensitive and selective determination of Try in biological fluids.


Assuntos
Grafite/química , Nanoestruturas/química , Tirosina/análise , Aminoácidos/química , Líquidos Corporais/química , Humanos , Limite de Detecção , Microscopia Eletrônica de Varredura , Fenóis/química , Espectroscopia de Infravermelho com Transformada de Fourier , Tirosina/sangue , Tirosina/urina
20.
Toxicol Lett ; 299: 11-20, 2018 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-30165092

RESUMO

A method is described allowing forensic analysis of plasma samples to prove human poisoning with the organophosphorus pesticides omethoate (OM) and dimethoate (DIM). Upon incubation of human serum albumin (HSA) with both pesticides tyrosine residues were phosphorylated. In addition, a novel disulfide-adduct between the identical thiol-containing leaving group of OM and DIM (2-mercapto-N-methylacetamide, MNMA) and the only free cysteine residue in HSA (Cys34) was formed. Following pronase-catalyzed proteolysis either O,O-dimethyl phosphotyrosine (Tyr-dmp) or O,O-dimethyl thiophosphotyrosine (Tyr-dmsp) as well as the cysteine-proline dipeptide disulfide-adduct (MNMA-CysPro) were produced. All biomarkers were simultaneously detected using modern microbore liquid chromatography-electrospray ionization high-resolution tandem-mass spectrometry (µLC-ESI MS/HR MS). Corresponding limits of identification (LOI) for tyrosine-adducts (LOIOM: 30 µM, LOIDIM: 120 µM) and disulfide-adducts (LOIOM: 1.2 µM, LOIDIM: 30 µM) demonstrated that MNMA-CysPro allowed a considerably more sensitive detection. Finally, this novel method was applied to a plasma sample of an 87-year-old man, who had unintentionally ingested the pesticide Roxion® containing DIM as active ingredient. Unambiguous proof of poisoning demonstrated suitability of the novel biomarkers for sensitive verification analysis.


Assuntos
Dimetoato/análogos & derivados , Dipeptídeos/sangue , Dissulfetos/sangue , Intoxicação por Organofosfatos/sangue , Praguicidas/toxicidade , Albumina Sérica Humana/metabolismo , Tirosina/sangue , Biomarcadores/sangue , Dimetoato/toxicidade , Toxicologia Forense/métodos , Humanos , Fosforilação , Ligação Proteica , Estabilidade Proteica , Proteólise
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