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1.
NanoImpact ; 35: 100517, 2024 Jul.
Article de Anglais | MEDLINE | ID: mdl-38848992

RÉSUMÉ

Superparamagnetic iron oxide nanoparticles (SPIONs) have gained significant attention in biomedical research due to their potential applications. However, little is known about their impact and toxicity on testicular cells. To address this issue, we conducted an in vitro study using primary mouse testicular cells, testis fragments, and sperm to investigate the cytotoxic effects of sodium citrate-coated SPIONs (Cit_SPIONs). Herein, we synthesized and physiochemically characterized the Cit_SPIONs and observed that the sodium citrate diminished the size and improved the stability of nanoparticles in solution during the experimental time. The sodium citrate (measured by thermogravimetry) was biocompatible with testicular cells at the used concentration (3%). Despite these favorable physicochemical properties, the in vitro experiments demonstrated the cytotoxicity of Cit_SPIONs, particularly towards testicular somatic cells and sperm cells. Transmission electron microscopy analysis confirmed that Leydig cells preferentially internalized Cit_SPIONs in the organotypic culture system, which resulted in alterations in their cytoplasmic size. Additionally, we found that Cit_SPIONs exposure had detrimental effects on various parameters of sperm cells, including motility, viability, DNA integrity, mitochondrial activity, lipid peroxidation (LPO), and ROS production. Our findings suggest that testicular somatic cells and sperm cells are highly sensitive and vulnerable to Cit_SPIONs and induced oxidative stress. This study emphasizes the potential toxicity of SPIONs, indicating significant threats to the male reproductive system. Our findings highlight the need for detailed development of iron oxide nanoparticles to enhance reproductive nanosafety.


Sujet(s)
Nanoparticules magnétiques d'oxyde de fer , Spermatozoïdes , Testicule , Mâle , Animaux , Souris , Testicule/effets des médicaments et des substances chimiques , Nanoparticules magnétiques d'oxyde de fer/toxicité , Nanoparticules magnétiques d'oxyde de fer/composition chimique , Spermatozoïdes/effets des médicaments et des substances chimiques , Stress oxydatif/effets des médicaments et des substances chimiques , Survie cellulaire/effets des médicaments et des substances chimiques , Cellules de Leydig/effets des médicaments et des substances chimiques , Cellules de Leydig/métabolisme , Peroxydation lipidique/effets des médicaments et des substances chimiques , Espèces réactives de l'oxygène/métabolisme , Citrate de sodium , Cellules cultivées
2.
BMC Nephrol ; 24(1): 353, 2023 11 30.
Article de Anglais | MEDLINE | ID: mdl-38036951

RÉSUMÉ

BACKGROUND: Prolonged hemodialysis (HD) is performed from 6 to 12 h and can last up to 24 h. To prevent system clotting some studies suggest that Regional Citrate Anticoagulation (RCA) use reduces bleeding rates relative to systemic heparin. However, there may be difficulties in the patient's clinical management and completing the prescribed HD with Genius system using RCA. OBJECTIVE: To analyze safety Quality Indicators (IQs) and follow up on prolonged HD with 4% sodium citrate solution in a Genius® hybrid system. METHODS: This is a retrospective cohort conducted in an intensive care unit. RESULTS: 53 random sessions of prolonged HD with 4% sodium citrate solution of critically ill patients with AKI assessed. Evaluated safety indicators were dysnatremia and metabolic alkalosis, observed in 15% and 9.4% of the sessions, respectively. Indicators of effectiveness were system clotting which occurred in 17.3%, and the minimum completion of the prescribed HD time, which was 75.5%. CONCLUSION: The assessment of the indicators showed that the use of RCA with a 4% sodium citrate solution in prolonged HD with the Genius system in critically ill patients with AKI can be performed in a simple, safe, and effective way.


Sujet(s)
Atteinte rénale aigüe , Acide citrique , Humains , Atteinte rénale aigüe/thérapie , Anticoagulants/usage thérapeutique , Citrates/usage thérapeutique , Acide citrique/usage thérapeutique , Maladie grave/thérapie , Héparine/effets indésirables , Indicateurs qualité santé , Dialyse rénale , Études rétrospectives , Citrate de sodium
3.
Prep Biochem Biotechnol ; 52(9): 1051-1059, 2022.
Article de Anglais | MEDLINE | ID: mdl-35100517

RÉSUMÉ

The production of 2,3-butanediol (2,3-BDO), a dialcohol of great interest for the food, chemical, and pharmaceutical industry, through the fermentation of biomass, is a sustainable process strategic position for countries with abundant biomass generated by the agribusiness. However, the downstream process of 2,3-BDO is onerous due to the complexity of fermentation broth and the physical-chemical characteristics of the 2,3-BDO. This study investigated the feasibility of 2,3-BDO extraction from model aqueous solutions using aqueous two-phase systems (ATPS). A central composite rotational design (CCRD) was employed to evaluate different ATPS compositions and the influences on the 2,3-BDO recovery and partition coefficient. The polyethylene glycol (PEG) and different concentrations of sodium citrate, ammonium sulfate, and potassium phosphate were investigated. The concentration of salt and PEG in the ATPS was identified as the most significant factors influencing the recovery and partition coefficient of 2,3-BDO. The recovery of 2,3-BDO reached 94.5% and was obtained when the system was composed of 36.22% (w/w) of PEG 4000 and 4.47% (w/w) of potassium phosphate. The results indicate that ATPS based on PEG-salt has a high potential for industrial application, using mild conditions and a simple process for recovering and purifying the 2,3-BDO produced from microbiological synthesis.


Sujet(s)
Chlorure de sodium , Eau , Sulfate d'ammonium , Butylène glycols , Phosphates , Polyéthylène glycols/composition chimique , Composés du potassium , Chlorure de sodium/composition chimique , Citrate de sodium , Eau/composition chimique
4.
Rev Argent Microbiol ; 54(3): 175-180, 2022.
Article de Anglais | MEDLINE | ID: mdl-35012807

RÉSUMÉ

Achromobacter spp. are increasingly recognized as emerging pathogens in immunocompromised patients or suffering cystic fibrosis, but unusual in immunocompetent hosts or individuals that underwent surgery. In this study we describe two simultaneous events attributable to two different Achromobacter spp. contaminated sources. One event was related to an episode of pseudo-bacteremia due to sodium citrate blood collection tubes contaminated with Achromobacter insuavis and the other to Achromobacter genogroup 20 infection and colonization caused by an intrinsically contaminated chlorhexidine soap solution. Both threatened the appropriate use of antimicrobials. Molecular approaches were critical to achieving the accurate species identification and to assess the clonal relationship, strengthening the need for dedicated, multidisciplinary and collaborative work of microbiologists, specialists in infectious diseases, epidemiologists and nurses in the control of infections to clarify these epidemiological situations.


Sujet(s)
Achromobacter , Infection croisée , Infections bactériennes à Gram négatif , Achromobacter/génétique , Chlorhexidine , Infection croisée/épidémiologie , Épidémies de maladies , Infections bactériennes à Gram négatif/épidémiologie , Humains , Savons , Citrate de sodium
5.
Molecules ; 26(19)2021 Sep 22.
Article de Anglais | MEDLINE | ID: mdl-34641270

RÉSUMÉ

The conjugation of biomolecules to magnetic nanoparticles has emerged as promising approach in biomedicine as the treatment of several diseases, such as cancer. In this study, conjugation of bioactive peptide fractions from germinated soybeans to magnetite nanoparticles was achieved. Different fractions of germinated soybean peptides (>10 kDa and 5-10 kDa) were for the first time conjugated to previously coated magnetite nanoparticles (with 3-aminopropyltriethoxysilane (APTES) and sodium citrate) by the Ugi four-component reaction. The crystallinity of the nanoparticles was corroborated by X-ray diffraction, while the particle size was determined by scanning transmission electron microscopy. The analyses were carried out using infrared and ultraviolet-visible spectroscopy, dynamic light scattering, and thermogravimetry, which confirmed the coating and functionalization of the magnetite nanoparticles and conjugation of different peptide fractions on their surfaces. The antioxidant activity of the conjugates was determined by the reducing power and hydroxyl radical scavenging activity. The nanoparticles synthesized represent promising materials, as they have found applications in bionanotechnology for enhanced treatment of diseases, such as cancer, due to a higher antioxidant capacity than that of fractions without conjugation. The highest antioxidant capacity was observed for a >10 kDa peptide fraction conjugated to the magnetite nanoparticles coated with APTES.


Sujet(s)
Antioxydants/pharmacologie , Glycine max/composition chimique , Nanoparticules de magnétite/composition chimique , Peptides/pharmacologie , Antioxydants/composition chimique , Piégeurs de radicaux libres/composition chimique , Germination , Taille de particule , Peptides/composition chimique , Propylamines/composition chimique , Silanes/composition chimique , Citrate de sodium/composition chimique , Spectroscopie infrarouge à transformée de Fourier , Thermogravimétrie , Diffraction des rayons X
6.
Prep Biochem Biotechnol ; 50(6): 619-626, 2020.
Article de Anglais | MEDLINE | ID: mdl-32013723

RÉSUMÉ

The protease from Aspergillus tamarii Kita UCP1279 extraction by aqueous two-phase PEG-Citrate (ATPS) systems, using a factorial design 24, was investigated. Then, the variables studied were polyethylene glycol (PEG) molar mass (MPEG), concentrations of PEG (CPEG) and citrate (CCIT), and pH. The responses analyzed were the partition coefficient (K), activity yield (Y) and purification factor (PF). The thermodynamic parameters of the ATPS partition were estimated as a function of temperature. ATPS was able to pre-purify the protease (PF = 1.6) and obtained 84% activity yield. The thermodynamic parameters ΔG°m (-10.89 kJ mol-1), ΔHm (-5.0 kJ mol-1) and partition ΔSm (19.74 J mol-1 K-1) showed that the preferential migration of almost all protein contaminants of the crude extract to the salt-rich phase, while the preferred protease was the PEG rich phase. The extracted enzyme presents optimum temperature and pH at range of 40-50 °C and 9.0-11.0, respectively. Moreover, the enzyme was identified as serine protease based on inhibition profile. ATPS showed the satisfactory performance as the first step for Aspergillus tamarii Kita UCP1279 protease pre-purification.


Sujet(s)
Aspergillus/enzymologie , Polyéthylène glycols/composition chimique , Protéases à sérine/biosynthèse , Protéases à sérine/isolement et purification , Citrate de sodium/composition chimique , Thermodynamique , Eau/composition chimique , Concentration en ions d'hydrogène , Ions/pharmacologie , Métaux/pharmacologie , Masse moléculaire , Inhibiteurs de protéases/pharmacologie , Transduction du signal/effets des médicaments et des substances chimiques , Température
7.
Rev. Fac. Cienc. Méd. Univ. Cuenca ; 38(1): 65-71, 2020. ilus, tab
Article de Espagnol | LILACS | ID: biblio-1100688

RÉSUMÉ

Introducción: la pseudotrombocitopenia inducida por EDTA (ácido etilendiamino tetraacético) es un fenómeno de aglutinación de plaquetas que se presenta in vitro, mediado por anticuerpos anti-plaquetarios de tipo IgG, IgA o IgM dirigidos contra el complejo glucoproteínico IIb/IIIa de la membrana plaquetaria. Caso clínico: presentamos un caso clínico de una paciente de 59 años de edad sometida a recambio valvular aórtico; clínicamente con evolución favorable durante el periodo posquirúrgico, sin embargo, en estudios de control se registra trombocitopenia severa, lo que llevo a cuestionar el uso de anticoagulantes y la necesidad de transfusión de plaquetas. Al realizar estudios complementarios se encontró agregados plaquetarios en el frotis de sangre periférica, posteriormente se realizó recuento seriado de plaquetas y comparación del histograma plaquetario, catalogando el caso como pseudotrombocitopenia. Conclusión: La trombocitopenia por agregados plaquetarios es una condición de baja incidencia (0.07% a 0.1%). Se debe a la agregación de plaquetas in vitro asociada al uso de anticoagulantes, frecuentemente etilendiaminotetraacético (EDTA), en el presente caso también se asoció al uso de citrato de sodio. Este problema no se asocia a sangrado, sin embargo su desconocimiento pudo haber llevado a realizar procedimientos diagnósticos y terapéuticos innecesarios


Introduction: EDTA (ethylenediamine tetraacetic acid) ­induced by pseudothrombocytopenia is a platelet agglutination phenomenon that occurs in vitro, which are mediated by anti-platelet antibodies of the IgG, IgA or IgM type directed against the glycoprotein complex IIb / IIIa of the platelet membrane . Clinical case: This is a clinical case of a 59-yearsold patient undergoing aortic valve replacement, clinically with a favorable evolution during the postoperative period, however, in control studies, severe thrombocytopenia was recorded, which led to questioning the use of anticoagulants and the need for platelet transfusion. When carrying out complementary studies, aggregated platelet were found in the peripheral blood smear, later, a serial platelet count and comparison of the platelet histogram were performed, classifying the case as pseudotrombocytopenia. Conclusion: Thrombocytopenia due to aggregated platelet is a low incidence condition (0.07% to 0.1%). It is due to the aggregation of platelets in vitro associated with the use of anticoagulants [frequently ethylenediamine tetra acetic (EDTA)]; in the present case it was also associated with the use of sodium citrate. This problem is not associated with bleeding; however its lack of knowledge leads to unnecessary diagnostic and therapeutic procedures.


Sujet(s)
Humains , Femelle , Adulte d'âge moyen , Thrombopénie/diagnostic , Thrombopénie/étiologie , Thrombopénie/sang , Agrégation plaquettaire/effets des médicaments et des substances chimiques , Acide édétique/effets indésirables , Citrate de sodium/effets indésirables , Anticoagulants/effets indésirables
8.
Trop Med Int Health ; 24(11): 1320-1329, 2019 11.
Article de Anglais | MEDLINE | ID: mdl-31505102

RÉSUMÉ

OBJECTIVES: Human enteroparasites are considered a serious public health problem in underdeveloped countries located in world regions with tropical, subtropical and equatorial climates. These parasites are commonly diagnosed by the Parasitological Examination of Faeces (PEF), performed by conventional techniques and/or commercial kits that result in tests with low-to-moderate sensitivity, due to the use of destructive chemical solvents to parasite structures, and to present excess adipose substance and digestive residues in their microscopic slides. In order to improve the efficacy of these tests/examinations, this study aimed to investigate a new alternative for the PEF, with the use of Aqueous Biphasic System (ABS). METHODS: For this, four ABSs containing poly (ethylene glycol), PEG (PEG-4000 and PEG-6000), dipotassium phosphate and sodium citrate at different concentrations in the biphasic systems were evaluated with faecal samples containing eggs of Ascaris lumbricoides. RESULTS: The ABS consisting of PEG-4000 and dipotassium phosphate, at concentrations of 55% w/w and 20% w/w, respectively, achieved 100% satisfactory results compared to the conventional TF-Test technique in terms of preservation and concentration of A. lumbricoides eggs, with adequate separation of digestive residues, without using a centrifuge or chemical solvents that may cause harm to the parasites. CONCLUSIONS: This study presents ABS as a new low-cost technical principle for the detection of parasite eggs in PEF. The new technique is simple, fast, non-toxic, not harmful to the parasite and does not require a centrifuge.


UTILISATION DU SYSTÈME BIPHASIQUE AQUEUX COMME ALTERNATIVE À LA CONCENTRATION DES ŒUFS D'ASCARIS LUMBRICOIDES, AVEC SÉPARATION NON TOXIQUE DES RÉSIDUS FÉCAUX ET DES GRAISSES: OBJECTIFS: Les entéroparasites humains sont considérés comme un sérieux problème de santé publique dans les pays sous-développés situés dans des régions du monde aux climats tropicaux, subtropicaux et équatoriaux. L'examen parasitologique des matières fécales (EPMF) permet généralement de diagnostiquer ces parasites, à l'aide de techniques classiques et/ou de kits commerciaux, conduisant à des tests de sensibilité faible à modérée, dus à l'utilisation de solvants chimiques destructeurs pour les structures du parasite et résultant en excès de substances adipeuses et de résidus digestifs dans leurs lames microscopiques. Afin d'améliorer l'efficacité de ces tests/examens, cette étude visait à étudier une nouvelle alternative à l'EPMF, avec l'utilisation du Système Biphasique Aqueux (SBA). MÉTHODES: Pour cela, quatre SBA contenant du poly (éthylène glycol), du PEG (PEG-4000 et PEG-6000), du phosphate dipotassique et du citrate de sodium à différentes concentrations ont été évalués avec des échantillons de matières fécales contenant des œufs d'Ascaris lumbricoides. RÉSULTATS: Le SBA constitué de PEG-4000 et de phosphate dipotassique, à des concentrations respectives de 55% poids/poids et 20% poids/poids, a obtenu des résultats satisfaisants à 100% par rapport à la technique conventionnelle du TF-Test, en termes de préservation et de concentration des œufs de A. lumbricoides, avec une séparation adéquate des résidus digestifs, sans utiliser de centrifugeuse ni de solvants chimiques pouvant détruire les parasites. CONCLUSIONS: Cette étude présente le SBA comme un nouveau principe technique peu coûteux pour la détection des œufs de parasites dans l'EPMF. La nouvelle technique est simple, rapide, non toxique, n'endommage pas le parasite et ne nécessite pas de centrifugeuse.


Sujet(s)
Ascaris lombricoides , Techniques et procédures diagnostiques , Fèces/parasitologie , Animaux , Numération des oeufs de parasites , Phosphates/composition chimique , Polyéthylène glycols/composition chimique , Composés du potassium/composition chimique , Sensibilité et spécificité , Citrate de sodium/composition chimique
9.
J Dairy Res ; 86(3): 337-340, 2019 Aug.
Article de Anglais | MEDLINE | ID: mdl-31385560

RÉSUMÉ

The aim of this work was to use X-ray diffraction to identify substances used for adulteration of raw milk and to determine if crystallographic analysis can detect extraneous substances in milk. Two unknown substances were sent anonymously by employers linked to the dairy chain, who claimed that they were added directly in milk prior to water addition by truck drivers. The samples were analyzed by X-ray diffraction and submitted to physicochemical analysis. The first substance was identified by X-ray diffraction as sodium citrate, complying with its physicochemical attributes, such as the powerful ability to decrease the freezing point. The second substance was identified by X-ray diffraction as sucrose and this result was also in agreement with its ability to increase the density, decrease the freezing point and finally, to be positive for sucrose in the resorcinol qualitative test. To evaluate if X-ray diffraction can detect extraneous substances already mixed in milk, fresh raw milk samples tampered with urea, sodium hydroxide, sodium citrate and sucrose were freeze dried and analyzed by X-ray diffraction, with no detection of any extraneous substances at any percentage. This is the first report of attempted diagnosis of extraneous substances in milk by X-ray diffraction. However, this technique can be useful only when applied to identify substances used for adulteration prior to its dilution in milk, since the amorphous nature of milk seems to be a limitation for the accurate detection of extraneous substances.


Sujet(s)
Cristallographie aux rayons X/médecine vétérinaire , Contamination des aliments/analyse , Lait/composition chimique , Animaux , Bovins , Phénomènes chimiques , Citrate de sodium/analyse , Saccharose/analyse , Eau/analyse
10.
J Int Soc Sports Nutr ; 16(1): 32, 2019 Aug 01.
Article de Anglais | MEDLINE | ID: mdl-31370896

RÉSUMÉ

BACKGROUND: The efficacy of sodium citrate supplementation (SC) in exercise performance is unclear. Therefore, the aim of this study was to investigate the effect of SC on skilled tennis performance. METHODS: Ten Brazilian nationally-ranked young male tennis players (age: 17 ± 1 yrs.; stature: 176.7 ± 5.2 cm; body mass: 68.4 ± 7.9 kg) participated in this crossover, placebo-controlled, double-blind study. Upon arrival, at baseline, in both experimental sessions blood was collected, then subjects ingested either sodium citrate (SC - 0.5 g.kg-1BM in capsules of 500 mg) or a placebo (PLA). Two hours later, pre-match blood was collected then skills tests (skill tennis performance test - STPT, repeated-sprint ability shuttle test - RSA) were performed followed by a 1-h simulated match. Immediately following the match, blood was again collected, and STPT, and RSA were administered. RESULTS: All metabolic parameters (i.e. base excess, pH, bicarbonate, and blood lactate) increased (p < 0.001) from baseline to pre-match and post-match in SC condition. Each metabolic parameter was greater (p < 0.001) in SC compared to PLA condition at both pre- and post-match. The SC condition elicited a greater (p < 0.01) shot consistency at post-match in the STPT vs. PLA condition (SC: 58.5 ± 14.8% vs. PLA: 40.4 ± 10.4%). A greater (p < 0.001) amount of games won was observed in the simulated match for SC condition vs. PLA condition (SC: 8.0 ± 1.6 vs. PLA: 6.0 ± 1.7). Additionally, the games won during the simulated match in SC condition was positively correlated with percentage shot consistency (r = 0.67, p < 0.001). CONCLUSIONS: The current findings suggest that SC supplementation is an effective ergogenic aid to enhance skilled tennis performance.


Sujet(s)
Performance sportive , Substances améliorant les performances/administration et posologie , Citrate de sodium/administration et posologie , Tennis , Adolescent , Hydrogénocarbonates/sang , Études croisées , Méthode en double aveugle , Épreuve d'effort , Humains , Acide lactique/sang , Mâle , Phénomènes physiologiques nutritionnels du sport
11.
Part Fibre Toxicol ; 16(1): 22, 2019 06 03.
Article de Anglais | MEDLINE | ID: mdl-31159811

RÉSUMÉ

BACKGROUND: The blood brain barrier (BBB) is the bottleneck of brain-targeted drug development. Due to their physico-chemical properties, nanoparticles (NP) can cross the BBB and accumulate in different areas of the central nervous system (CNS), thus are potential tools to carry drugs and treat brain disorders. In vitro systems and animal models have demonstrated that some NP types promote neurotoxic effects such as neuroinflammation and neurodegeneration in the CNS. Thus, risk assessment of the NP is required, but current 2D cell cultures fail to mimic complex in vivo cellular interactions, while animal models do not necessarily reflect human effects due to physiological and species differences. RESULTS: We evaluated the suitability of in vitro models that mimic the human CNS physiology, studying the effects of metallic gold NP (AuNP) functionalized with sodium citrate (Au-SC), or polyethylene glycol (Au-PEG), and polymeric polylactic acid NP (PLA-NP). Two different 3D neural models were used (i) human dopaminergic neurons differentiated from the LUHMES cell line (3D LUHMES) and (ii) human iPSC-derived brain spheroids (BrainSpheres). We evaluated NP uptake, mitochondrial membrane potential, viability, morphology, secretion of cytokines, chemokines and growth factors, and expression of genes related to ROS regulation after 24 and 72 h exposures. NP were efficiently taken up by spheroids, especially when PEGylated and in presence of glia. AuNP, especially PEGylated AuNP, effected mitochondria and anti-oxidative defense. PLA-NP were slightly cytotoxic to 3D LUHMES with no effects to BrainSpheres. CONCLUSIONS: 3D brain models, both monocellular and multicellular are useful in studying NP neurotoxicity and can help identify how specific cell types of CNS are affected by NP.


Sujet(s)
Encéphale/effets des médicaments et des substances chimiques , Or/toxicité , Nanoparticules métalliques/toxicité , Modèles biologiques , Polyesters/composition chimique , Sphéroïdes de cellules/effets des médicaments et des substances chimiques , Encéphale/métabolisme , Encéphale/anatomopathologie , Techniques de culture cellulaire , Lignée cellulaire , Survie cellulaire/effets des médicaments et des substances chimiques , Neurones dopaminergiques/effets des médicaments et des substances chimiques , Neurones dopaminergiques/métabolisme , Neurones dopaminergiques/anatomopathologie , Systèmes de délivrance de médicaments , Expression des gènes/effets des médicaments et des substances chimiques , Or/métabolisme , Humains , Potentiel de membrane mitochondriale/effets des médicaments et des substances chimiques , Stress oxydatif/effets des médicaments et des substances chimiques , Stress oxydatif/génétique , Polyesters/métabolisme , Polyéthylène glycols/composition chimique , Citrate de sodium/composition chimique , Sphéroïdes de cellules/métabolisme , Propriétés de surface
12.
Br J Sports Med ; 52(14): 942-943, 2018 Jul.
Article de Anglais | MEDLINE | ID: mdl-27678471

RÉSUMÉ

Sodium citrate (SCit) supplementation has been studied for several years as a strategy to reduce the muscle fatigue induced by H+ ion accumulation within the skeletal muscle during high-intensity, short-duration exercise. Several investigations have been published on this matter, and appear to indicate that SCit is not effective as an ergogenic aid, despite its ability to increase extracellular buffering capacity. In this short report, we briefly discuss the SCit results previously published in the literature and consider them in light of new and promising findings, which appear to address issues associated with previous study designs. We also suggest possible reasons for the current lack of reported ergogenic effects from this nutritional strategy and make recommendations that may re-define research in this area.


Sujet(s)
Citrates/pharmacologie , Compléments alimentaires , Fatigue musculaire/effets des médicaments et des substances chimiques , Muscles squelettiques/effets des médicaments et des substances chimiques , Substances améliorant les performances/pharmacologie , Humains , Muscles squelettiques/physiologie , Citrate de sodium
13.
Braz J Med Biol Res ; 51(1): e6378, 2017 Nov 17.
Article de Anglais | MEDLINE | ID: mdl-29185591

RÉSUMÉ

The aim of this study was to discuss the safety and efficacy of regional citrate anticoagulation (RCA) on continuous blood purification (CBP) during the treatment of multiple organ dysfunction syndrome (MODS). Thirty-five patients with MODS were divided into two groups: the local citrate anticoagulation (RCA) group, and the heparin-free blood purification (hfBP) group. The MODS severity was assessed according to Marshall's MODS score criteria. Blood coagulation indicators, blood pressure, filter lifespan, filter replacement frequency, anticoagulation indicators, and main metabolic and electrolyte indicators were analyzed and compared between RCA and hfBP groups. RCA resulted in lower blood pressure than hfBP. The filter efficacy in RCA treatment was longer than in the hfBP group. The blood clearance of creatine, blood urea nitrogen and uric acid was better in the RCA group. RCA also led to higher pH than hfBP. Neither treatment resulted in severe bleeding events. In addition, MODS score was positively correlated with prothrombin time and activated partial thromboplastin time but negatively correlated with platelet concentration. RCA is a safer and more effective method in CBP treatment; however, it could also lead to low blood pressure and blood alkalosis.


Sujet(s)
Anticoagulants/pharmacologie , Citrates/pharmacologie , Acide citrique/pharmacologie , Glucose/pharmacologie , Hémofiltration/méthodes , Défaillance multiviscérale/thérapie , Adulte , Sujet âgé , Anticoagulants/usage thérapeutique , Coagulation sanguine/effets des médicaments et des substances chimiques , Pression sanguine/effets des médicaments et des substances chimiques , Citrates/usage thérapeutique , Acide citrique/usage thérapeutique , Femelle , Glucose/usage thérapeutique , Hémorragie/induit chimiquement , Héparine/pharmacologie , Héparine/usage thérapeutique , Humains , Mâle , Adulte d'âge moyen , Valeurs de référence , Reproductibilité des résultats , Facteurs de risque , Indice de gravité de la maladie , Citrate de sodium , Facteurs temps , Résultat thérapeutique
14.
Protein Expr Purif ; 129: 25-30, 2017 01.
Article de Anglais | MEDLINE | ID: mdl-27623151

RÉSUMÉ

The structure and catalytic activity of xylanase from Thermomyces lanuginosus were studied in different media (containing polyethylene glycol -PEG- or salt) at different temperatures. The aim was to study how the native structure of the enzyme is affected to understand the partitioning behavior of xylanase in PEG/sodium citrate (PEG/NaCit) aqueous two-phase systems. The presence of PEGs of different molar masses slightly altered the native structure of xylanase, although its catalytic activity was not affected. All the polymers assayed protect the native structure (and catalytic activity) of xylanase against temperature, except for PEG1000. Surface hydrophobicity experiments showed that xylanase favorable interacts with PEGs. Partitioning experiments confirmed this result and demonstrated that PEG1000/NaCit is the best system to partition xylanase from Thermomyces lanuginosus, since the Kp was 17.7 ± 0.3.


Sujet(s)
Ascomycota/enzymologie , Citrates/composition chimique , Endo-1,4-beta xylanases , Protéines fongiques , Polyéthylène glycols/composition chimique , Endo-1,4-beta xylanases/composition chimique , Endo-1,4-beta xylanases/isolement et purification , Protéines fongiques/composition chimique , Protéines fongiques/isolement et purification , Polyéthylène glycols/analyse , Citrate de sodium
15.
Braz. J. Microbiol. ; 47(3): 757-763, Jul-Set. 2016. graf, tab
Article de Anglais | VETINDEX | ID: vti-23426

RÉSUMÉ

The inhibition of Listeria monocytogenes ATCC 7644 on fresh-cut tomato was investigated using nisin alone, and in combinations with organic salts. Nisin at a concentration of 5000 UI/mL was introduced alone or in combination with an organic salt (sodium citrate or sodium acetate each at 3 and 5 g/100 mL each) on fresh-cut tomato previously inoculated with 108 CFU/mL of L. monocytogenes ATCC 7644. Chlorine at 200 ppm was used as a control. The inoculated samples were incubated at different temperatures (4, 10 and 25 °C) and examined at 0, 24, 48 and 72 h. The effects of the antimicrobial treatments on quality parameters of tomato (pH, soluble solids, titratable acidity and vitamin C) were also evaluated, and colour parameters were observed at the lowest storage temperature for 10 days. Both nisin and the organic salts inhibited growth of L. monocytogenes, but the combinations of two compounds were more effective. The nisin-sodium citrate (5%) combination was significantly (p 0.05) effective, while chlorine was least effective against L. monocytogenes. The quality parameters were substantially retained, especially at 4 °C, suggesting good shelf stability at a low temperature. These results substantiate the use of the cheap and eco-friendly approach to reducing this pathogen of health concern in common fresh produce.(AU)


Sujet(s)
Listeria monocytogenes/isolement et purification , Solanum lycopersicum/microbiologie , Nisine/administration et posologie , Citrate de sodium , Acétate de sodium
16.
Sports Med ; 45 Suppl 1: S71-81, 2015 Nov.
Article de Anglais | MEDLINE | ID: mdl-26553493

RÉSUMÉ

Intramuscular acidosis is a contributing factor to fatigue during high-intensity exercise. Many nutritional strategies aiming to increase intra- and extracellular buffering capacity have been investigated. Among these, supplementation of beta-alanine (~3-6.4 g/day for 4 weeks or longer), the rate-limiting factor to the intramuscular synthesis of carnosine (i.e. an intracellular buffer), has been shown to result in positive effects on exercise performance in which acidosis is a contributing factor to fatigue. Furthermore, sodium bicarbonate, sodium citrate and sodium/calcium lactate supplementation have been employed in an attempt to increase the extracellular buffering capacity. Although all attempts have increased blood bicarbonate concentrations, evidence indicates that sodium bicarbonate (0.3 g/kg body mass) is the most effective in improving high-intensity exercise performance. The evidence supporting the ergogenic effects of sodium citrate and lactate remain weak. These nutritional strategies are not without side effects, as gastrointestinal distress is often associated with the effective doses of sodium bicarbonate, sodium citrate and calcium lactate. Similarly, paresthesia (i.e. tingling sensation of the skin) is currently the only known side effect associated with beta-alanine supplementation, and it is caused by the acute elevation in plasma beta-alanine concentration after a single dose of beta-alanine. Finally, the co-supplementation of beta-alanine and sodium bicarbonate may result in additive ergogenic gains during high-intensity exercise, although studies are required to investigate this combination in a wide range of sports.


Sujet(s)
Acidose/prévention et contrôle , Compléments alimentaires , Exercice physique/physiologie , Muscles squelettiques/métabolisme , Composés du calcium/administration et posologie , Composés du calcium/effets indésirables , Composés du calcium/métabolisme , Citrates/administration et posologie , Citrates/effets indésirables , Citrates/métabolisme , Compléments alimentaires/effets indésirables , Métabolisme énergétique , Liquide extracellulaire/métabolisme , Humains , Concentration en ions d'hydrogène , Liquide intracellulaire/métabolisme , Lactates/administration et posologie , Lactates/effets indésirables , Lactates/métabolisme , Fatigue musculaire , Hydrogénocarbonate de sodium/administration et posologie , Hydrogénocarbonate de sodium/effets indésirables , Hydrogénocarbonate de sodium/sang , Citrate de sodium , Lactate de sodium/administration et posologie , Lactate de sodium/effets indésirables , Lactate de sodium/métabolisme , bêta-Alanine/administration et posologie , bêta-Alanine/effets indésirables , bêta-Alanine/métabolisme
17.
Rev Invest Clin ; 67(3): 191-8, 2015.
Article de Anglais | MEDLINE | ID: mdl-26202743

RÉSUMÉ

BACKGROUND: Primary distal renal tubular acidosis is a clinical disorder characterized by hyperchloremic metabolic acidosis, hypercalciuria, hypocitraturia, urinary acidification impairment, hypokalemia, metabolic bone disease, and nephrocalcinosis. Urinary acidification ability may be evaluated by an acidification test or maximum urinary pCO2 assessment with alkaline urine. The maximum urinary pCO2 test using acetazolamide and sodium bicarbonate is an easy test to confirm the lack of urine acidification in distal renal tubular acidosis in children. OBJECTIVE: To determine the urinary acidification ability using the maximum urinary pCO2 assessment in a group of children with a distal renal tubular acidosis diagnosis. MATERIAL AND METHODS: Thirty children were evaluated (13 males and 17 females); 23 children had been diagnosed with distal renal tubular acidosis by other physicians and were under alkali treatment with potassium and sodium citrates (21) and bicarbonate (2), and five children were not under alkali treatment. Two children had been diagnosed with primary distal renal tubular acidosis by our medical group. The maximum urinary pCO2 was determined by the oral intake of acetazolamide and sodium bicarbonate. RESULTS: Two cases with primary distal renal tubular acidosis were found, and they had a history of dehydration episodes during infancy and showed hyperchloremic metabolic acidosis with hypokalemia. They also exhibited urine acidification impairment with furosemide and reduced urinary pCO2 (< 60 mmHg), and the urine-blood pCO2 gradient was reduced in both cases (< 30 mmHg). One of them developed bilateral sensorineural deafness, while the other showed severe hypocitraturia. One case of proximal or type 2 renal tubular acidosis with hyperaminoaciduria was identified. Twenty-eight children displayed normal urinary acidification and did not show signs of distal renal tubular acidosis. CONCLUSIONS: The urinary acidification test with furosemide and urinary pCO2 assessment are reliable tests to identify the renal excretion of hydrogen ions (H+) and allow confirmation of the lack of urine acidification in distal renal tubular acidosis.


Sujet(s)
Acétazolamide/administration et posologie , Acidose tubulaire rénale/diagnostic , Dioxyde de carbone/urine , Hypokaliémie/épidémiologie , Acidose tubulaire rénale/physiopathologie , Enfant , Enfant d'âge préscolaire , Citrates/administration et posologie , Femelle , Furosémide/administration et posologie , Humains , Hypokaliémie/étiologie , Nourrisson , Mâle , Mexique , Hydrogénocarbonate de sodium/administration et posologie , Citrate de sodium
18.
BMC Vet Res ; 11: 60, 2015 Mar 14.
Article de Anglais | MEDLINE | ID: mdl-25889052

RÉSUMÉ

BACKGROUND: There is a lack information on the effects of the most commonly used anticoagulants for equine platelet rich plasmas (PRPs) elaboration on cell counts and growth factor release from platelet rich gels (PRGs). The aims of this study were 1) to compare the effects of the anticoagulants sodium citrate (SC), acid citrate dextrose solution A (ACD-A) and ACD-B on platelet (PLT), leukocyte (WBC) and on some parameters associated to platelet activation including mean platelet volume (MPV) and platelet distribution width (PDW) between whole blood, pure PRP (P-PRP) and platelet-poor plasma (PPP); 2) to compare transforming growth factor beta 1 (TGF-ß(1)) and platelet-derived growth factor isoform BB (PDGF-BB) concentrations in supernatants from pure PRG (P-PRG), platelet-poor gel (PPG), P-PRP lysate (positive control) and plasma (negative control); 3) to establish the possible correlations between all the studied cellular and molecular parameters. RESULTS: In all cases the three anticoagulants produced P-PRPs with significantly higher PLT counts compared with whole blood and PPP. The concentrations of WBCs were similar between P-PRP and whole blood, but significantly lower in PPP. The type of anticoagulant did not significantly affect the cell counts for each blood component. The anticoagulants also did not affect the MPV and PDW parameters. Independently of the anticoagulant used, all blood components presented significantly different concentrations of PDGF-BB and TGF-ß(1). The highest growth factor (GF) concentrations were observed from P-PRP lysates, followed by PRG supernatants, PPP lysates, PPG supernatants and plasma. Significant correlations were observed between PLT and WBC counts (ρ = 0.80), PLT count and TGF-ß(1) concentration (ρ = 0.85), PLT count and PDGF-BB concentration (ρ = 0.80) and PDGF-BB and TGF-ß(1) concentrations (ρ = 0.75). The type of anticoagulant was not correlated with any of the variables evaluated. CONCLUSIONS: The anticoagulants did not significantly influence cell counts or GF concentrations in equine PRP. However, ACD-B was apparently the worst anticoagulant evaluated. It is necessary to perform additional research to determine the effect of anticoagulants on the kinetics of GF elution from P-PRG.


Sujet(s)
Anticoagulants/pharmacologie , Hémogramme/médecine vétérinaire , Plaquettes/effets des médicaments et des substances chimiques , Citrates/pharmacologie , Acide citrique/pharmacologie , Glucose/analogues et dérivés , Equus caballus/sang , Plasma riche en plaquettes/effets des médicaments et des substances chimiques , Protéines proto-oncogènes c-sis/analyse , Facteur de croissance transformant bêta-1/analyse , Animaux , Bécaplermine , Plaquettes/composition chimique , Plaquettes/métabolisme , Test ELISA/médecine vétérinaire , Glucose/pharmacologie , Equus caballus/physiologie , Numération des leucocytes/médecine vétérinaire , Mâle , Activation plaquettaire/effets des médicaments et des substances chimiques , Numération des plaquettes/médecine vétérinaire , Plasma riche en plaquettes/composition chimique , Plasma riche en plaquettes/cytologie , Citrate de sodium
19.
Colloq. Agrar ; 11(1): 33-41, Jan-Jul. 2015. tab
Article de Portugais | VETINDEX | ID: biblio-1481285

RÉSUMÉ

Na rotina clínica veterinária são utilizados diferentes tipos de anticoagulantes, escolhidos de acordo com o exame a ser solicitado. Animais agitados, agressivos, de difícil contenção e de pequeno porte podem ser fatores limitantes quando se deseja aliquotar a amostra em tubos com diferentes anticoagulantes. Assim, esse trabalho teve como objetivo avaliar os efeitos dos anticoagulantes EDTA, Citrato de Sódio e Fluoreto associado ao EDTA, nos resultados dos exames bioquímicos de rotina realizados em cães e compará-los com o soro. Verificou-se que o plasma obtido com o anticoagulante EDTA resultou em alterações nas dosagens de glicose, colesterol e cálcio. Amostras obtidas com Citrato de Sódio tiveram resultados inferiores ao do soro em todos os parâmetros avaliados, com exceção da ALT. O anticoagulante Fluoreto associado ao EDTA, apenas nas dosagens de uréia e glicose, não resultou em alterações estatísticas quando comparado ao soro.


Different types of anticoagulants are used in the routine of a veterinary clinic, which are chosen based on the exam to be performed. Agitated, aggressive, of hard contention and small size animals can be a limiting factor when it is wished to separate samples into tubes with different anticoagulants. Therefore, this study had as the objective evaluate the effects of anticoagulants: EDTA, sodium citrate and sodium fluorite associated with EDTA, in the results of routine plasma biochemistry performed in dogs and compare it with serum. Blood samples of 10 clinically healthy dogs were collected and placed in different tubes with each anticoagulant and one without to obtain serum. Albumin, alanine aminotransferase (ALT), calcium, total cholesterol, creatine, phosphorus, glucose, total protein (PT) and urea concentrations were measured by spectophotometric. It was found that plasma obtained with EDTA anticoagulant resulted in dosage alterations for glucose, cholesterol and calcium. Samples obtained with sodium citrate presented results lower than serum in all analyzed parameters, except for ALT. The anticoagulant sodium fluorite with EDTA only didn’t result in statistical differences when compared to serum in the parameters of urea and glucose. Thus, serum is the most trustworthy sample to determine the biochemical profile of dogs, however some biochemical’s can be performed with plasma with EDTA such as creatine, ALT, urea, albumin, PT and phosphorus.


Sujet(s)
Animaux , Chiens , Anticoagulants , Citrate de sodium/administration et posologie , Fluorure de sodium/administration et posologie , Acide édétique/administration et posologie , Tests hématologiques/médecine vétérinaire , Tests sérologiques/médecine vétérinaire
20.
Colloq. agrar. ; 11(1): 33-41, Jan-Jul. 2015. tab
Article de Portugais | VETINDEX | ID: vti-27804

RÉSUMÉ

Na rotina clínica veterinária são utilizados diferentes tipos de anticoagulantes, escolhidos de acordo com o exame a ser solicitado. Animais agitados, agressivos, de difícil contenção e de pequeno porte podem ser fatores limitantes quando se deseja aliquotar a amostra em tubos com diferentes anticoagulantes. Assim, esse trabalho teve como objetivo avaliar os efeitos dos anticoagulantes EDTA, Citrato de Sódio e Fluoreto associado ao EDTA, nos resultados dos exames bioquímicos de rotina realizados em cães e compará-los com o soro. Verificou-se que o plasma obtido com o anticoagulante EDTA resultou em alterações nas dosagens de glicose, colesterol e cálcio. Amostras obtidas com Citrato de Sódio tiveram resultados inferiores ao do soro em todos os parâmetros avaliados, com exceção da ALT. O anticoagulante Fluoreto associado ao EDTA, apenas nas dosagens de uréia e glicose, não resultou em alterações estatísticas quando comparado ao soro.(AU)


Different types of anticoagulants are used in the routine of a veterinary clinic, which are chosen based on the exam to be performed. Agitated, aggressive, of hard contention and small size animals can be a limiting factor when it is wished to separate samples into tubes with different anticoagulants. Therefore, this study had as the objective evaluate the effects of anticoagulants: EDTA, sodium citrate and sodium fluorite associated with EDTA, in the results of routine plasma biochemistry performed in dogs and compare it with serum. Blood samples of 10 clinically healthy dogs were collected and placed in different tubes with each anticoagulant and one without to obtain serum. Albumin, alanine aminotransferase (ALT), calcium, total cholesterol, creatine, phosphorus, glucose, total protein (PT) and urea concentrations were measured by spectophotometric. It was found that plasma obtained with EDTA anticoagulant resulted in dosage alterations for glucose, cholesterol and calcium. Samples obtained with sodium citrate presented results lower than serum in all analyzed parameters, except for ALT. The anticoagulant sodium fluorite with EDTA only didnt result in statistical differences when compared to serum in the parameters of urea and glucose. Thus, serum is the most trustworthy sample to determine the biochemical profile of dogs, however some biochemicals can be performed with plasma with EDTA such as creatine, ALT, urea, albumin, PT and phosphorus.(AU)


Sujet(s)
Animaux , Chiens , Anticoagulants , Acide édétique/administration et posologie , Citrate de sodium/administration et posologie , Fluorure de sodium/administration et posologie , Tests hématologiques/médecine vétérinaire , Tests sérologiques/médecine vétérinaire
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