Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 42
Filtrar
1.
Ann Pharm Fr ; 74(5): 404-12, 2016 Sep.
Artigo em Francês | MEDLINE | ID: mdl-26944892

RESUMO

INTRODUCTION: In France, community pharmacy students performed a hospital pharmacy practice experience during the 5th year of the university curriculum. The purpose of a part of the content of the academic teaching program delivered before this practice experience is to prepare the students for their future hospital activities. It should enable them for the practical use of knowledge in order to improve pharmacotherapy, laboratory diagnosis and monitoring of patients' care. The aim of this study was to show if there are gaps in this program. METHODS: Fourteen students performing their clerkship in a teaching hospital were invited to highlight these gaps when they were gradually immersed in the pharmaceutical care. They did so under the careful observation of hospital pharmacist preceptors. These practitioners referred to professional guidelines, documentary tools used in daily clinical practice and publications supporting their pharmaceutical care practices. RESULTS: Shortcomings and gaps identified were: how to communicate with other healthcare professionals and the content of verbal exchanges, how to conduct a patient-centered consultation, documentation tools required for relevant pharmacist' interventions, codification of pharmacist's interventions, risks related to drug packaging and benefit risk assessment of health information technologies. DISCUSSION: These gaps represent a handicap by delaying the process that led to move from student to healthcare professional. Hospital pharmacist preceptors have to fill in these gaps before engaging students in pharmaceutical care. CONCLUSION: These results invite to revise partly the content of the academic teaching program delivered before the 5th year hospital pharmacy practice experience.


Assuntos
Currículo , Educação em Farmácia/métodos , Preceptoria/métodos , Estudantes de Farmácia , Adulto , Avaliação Educacional , Feminino , França , Humanos , Masculino , Farmacêuticos , Serviço de Farmácia Hospitalar , Adulto Jovem
2.
Osteoporos Int ; 27(7): 2301-2309, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27007475

RESUMO

UNLABELLED: The reported association between sclerostin and diabetes mellitus or abdominal fat may be biased by body size and bone mass. In older men, the association between serum sclerostin levels and metabolic syndrome lost significance after adjustment for bone mass. The association between sclerostin and energy metabolism needs further clarification. INTRODUCTION: Sclerostin is associated with abdominal fat, but this relationship may be biased since both are associated with body size and bone mass. Osteocalcin is a bone-derived hormone regulating energy metabolism. We assessed the association between serum sclerostin and metabolic syndrome (MetS) accounting for whole body mineral content (BMC) and osteocalcin. METHODS: We studied 694 men aged 51-85 who had serum osteocalcin and sclerostin measurements. RESULTS: Sclerostin was higher in 216 men with MetS compared with those without MetS (p < 0.005). Average sclerostin level increased significantly across the increasing number of MetS components. In multivariable models, higher sclerostin was associated with higher odds of MetS (odds ratio (OR) = 1.24/1 standard deviation (SD) increase [95 % confidence interval (95 % CI), 1.01-1.51]; p < 0.05). After further adjustment for BMC, the association of MetS with sclerostin lost significance, whereas that with osteocalcin remained significant. Men who were simultaneously in the highest sclerostin quartile and the lowest osteocalcin quartile had higher odds of MetS (OR = 2.14 [95 % CI, 1.15-4.18]; p < 0.05) vs. men being in the three lower sclerostin quartiles and three upper osteocalcin quartiles. After adjustment for whole body BMC, the association lost significance. CONCLUSIONS: Higher sclerostin level is associated with MetS severity; however, this association may be related to higher whole body BMC. The adjustment for BMC had no impact on the association between MetS and osteocalcin. Clinical cross-sectional studies do not elucidate the potential role of sclerostin in the regulation of energy metabolism and direct experimental approach is necessary.


Assuntos
Proteínas Morfogenéticas Ósseas/sangue , Síndrome Metabólica/sangue , Osteocalcina/sangue , Proteínas Adaptadoras de Transdução de Sinal , Idoso , Densidade Óssea , Proteínas Morfogenéticas Ósseas/fisiologia , Estudos de Coortes , França , Marcadores Genéticos/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Osteocalcina/fisiologia
4.
Horm Metab Res ; 46(6): 390-6, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24806747

RESUMO

Our aim was to characterize the effects and the underlying mechanisms of the lipid-regulating agent Niaspan(®) on both insulin action and triglyceride decrease in 20 nondiabetic, dyslipidemic men with metabolic syndrome receiving Niaspan(®) (2 g/day) or placebo for 8 weeks in a randomized, cross-over study. The effects on plasma lipid profile were characterized at the beginning and the end of each treatment period; insulin sensitivity was assessed using the 2-step euglycemic hyperinsulinemic clamp and VLDL-triglyceride turnover by measuring plasma glycerol enrichment, both at the end of each treatment period. The mechanism of action of nicotinic acid was studied in HuH7 and mouse primary hepatocytes. Lipid profile was improved after Niaspan(®) treatment with a significant-28% decrease in triglyceride levels, a+17% increase in HDL-C concentration and unchanged levels of fasting nonesterified fatty acid. VLDL-tri-glyceride production rate was markedly reduced after Niaspan(®) (-68%). However, the treatment induced hepatic insulin resistance, as assessed by reduced inhibition of endogenous glucose production by insulin (0.7±0.4 vs. 1.0±0.5 mg/kg · min, p<0.05) and decrease in fasting hepatic insulin sensitivity index (4.8±1.8 vs. 3.2±1.6, p<0.05) in the Niaspan(®) condition. Nicotinic acid also reduced insulin action in HuH7 and primary hepatocytes, independently of the activation of hepatic PKCε. This effect was associated with an increase in diacylglycerol and a decrease in tri-glyceride contents that occurred in the absence of modification of DGAT2 expression and activity. Eight weeks of Niaspan(®) treatment in dyslipidemic patients with metabolic syndrome induce hepatic insulin resistance. The mechanism could involve an accumulation of diacylglycerol and an alteration of insulin signaling in hepatocytes.


Assuntos
Insulina/farmacologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Fígado/metabolismo , Niacina/farmacologia , Animais , Linhagem Celular Tumoral , Diglicerídeos/metabolismo , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Humanos , Cinética , Lipoproteínas VLDL/metabolismo , Masculino , Camundongos , Pessoa de Meia-Idade , Niacina/administração & dosagem , Proteína Quinase C/antagonistas & inibidores , Proteína Quinase C/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Transdução de Sinais/efeitos dos fármacos , Triglicerídeos/metabolismo
5.
Ann Biol Clin (Paris) ; 70 Spec No 1: 151-59, 2012 Feb.
Artigo em Francês | MEDLINE | ID: mdl-22736701

RESUMO

Compliance to EN ISO 22870 standard for point-of-care testing (POCT) accreditation is close to those of EN ISO 15189 in central laboratory. However, it is mandatory to master the elements which are specific to POCT. In this paper, we describe the two main processes involved to help medical biologists to achieve standard requirements, particularly in the risk assessment study. The first process concerns the deployment of a POCT device in a hospital outside laboratory and the second is the classical process of medical biology testing, outlining the steps which are different from the laboratory testing process. Furthermore, we reference, in front of each sub-process described, the different articles published in the present volume detailing specific guidelines to master them.

6.
Ann Biol Clin (Paris) ; 70 Spec No 1: 161-6, 2012 Feb.
Artigo em Francês | MEDLINE | ID: mdl-22736702

RESUMO

EN ISO 22870 requires the medical laboratory director to form a multidisciplinary group for the management of point-of-care testing activities and to appoint a person responsible for this group. This article proposes to define the composition (representatives of the medical laboratory, care units owning point-of-care devices, administration), missions (introduction, follow-up and evaluation of point-of-care devices) and the decision circuit of this group and to describe the profile of the head and the tasks assigned.

7.
Ann Biol Clin (Paris) ; 70 Spec No 1: 207-31, 2012 Feb.
Artigo em Francês | MEDLINE | ID: mdl-22736705

RESUMO

This article proposes to organize the documentation system of point-of-care testing (POCT) to meet the requirements of EN ISO 22870. In a first part, we propose provisions to improve the control of documents circulating outside the laboratory and aimed at non-laboratory staff. Then we review POCT-related records and we propose an organization facilitating their audit. In the last part, a model of POCT quality plan is proposed : in addition to the quality manual, this document defines the specific measures taken in order to ensure the control of POCT.

8.
Ann Biol Clin (Paris) ; 70 Spec No 1: 233-48, 2012 Feb.
Artigo em Francês | MEDLINE | ID: mdl-22736706

RESUMO

Quality of point-of-care examinations depends on the quality assurance system settled. This paper describes the different tools used to control the pre-examination, examination and post-examination procedures taking part in the quality of patient care according to the requirements of the standard EN ISO 22870 and EN ISO 15189 as well. They include mainly: For the pre-examination phase, the sample traceability and for the analytical phase, the practice of internal quality control and the participation in external quality assessment programme.

9.
J Clin Endocrinol Metab ; 97(4): E575-83, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22319041

RESUMO

CONTEXT: Calcification inhibitor deficiencies, mineral imbalance, and phenotypic transformation of vascular cells to osteogenic cells initiate and sustain vascular calcification. Fibroblast growth factor-23 (FGF23) is a key molecule regulating mineral homeostasis. OBJECTIVE: Our objective was to assess the association of serum FGF23 levels with mineral metabolism parameters and abdominal aortic calcification (AAC) in men. DESIGN: This was a cross-sectional analysis in the STRAMBO cohort. SETTING: Men holding a private health insurance cover with Mutuelle de Travailleurs de la Région Lyonnaise were included in the study. PARTICIPANTS: Participants included male volunteers aged 20-87 (n = 1130). INTERVENTIONS: Nonfasting blood collection was done. AAC was semiquantitatively assessed from vertebral fracture assessment scans obtained using dual-energy x-ray absorptiometry. MAIN OUTCOME MEASURES: We evaluated the association between FGF23 concentration and AAC severity in men. RESULTS: In 350 men aged 60 yr or younger, FGF23 levels decreased with age (r = -0.21; P < 0.001) but were not associated with any other parameter. In 780 men aged over 60 yr, serum FGF23 correlated with age (r = 0.37; P < 0.001) and, after adjustment for confounders, with glomerular filtration rate (r = -0.31; P < 0.001) and PTH levels (r = 0.25; P < 0.001). After adjustment for confounders, self-reported ischemic heart disease, diabetes mellitus as well as higher concentrations of C-reactive protein and osteoprotegerin were all associated with higher FGF23 levels. After adjustment for confounders, subjects in the highest FGF23 quartile had higher prevalence of severe AAC compared with the three lower quartiles combined (odds ratio = 1.88; 95% confidence interval = 1.22-2.85; P < 0.005). CONCLUSIONS: In healthy older men, circulating FGF23 is associated with parameters of mineral metabolism, including bone metabolism-regulating cytokines, and with severe AAC independent of traditional risk factors.


Assuntos
Aorta Abdominal/patologia , Fatores de Crescimento de Fibroblastos/sangue , Calcificação Vascular/sangue , Absorciometria de Fóton , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Estudos de Coortes , Estudos Transversais , Fator de Crescimento de Fibroblastos 23 , França/epidemiologia , Taxa de Filtração Glomerular , Humanos , Masculino , Pessoa de Meia-Idade , Hormônio Paratireóideo/sangue , Prevalência , Índice de Gravidade de Doença , Calcificação Vascular/epidemiologia , Calcificação Vascular/patologia , Calcificação Vascular/fisiopatologia , Adulto Jovem
10.
Ann Pharm Fr ; 69(6): 306-16, 2011 Nov.
Artigo em Francês | MEDLINE | ID: mdl-22115134

RESUMO

INTRODUCTION: Deuterated glucose ([6,6-(2)H(2)]-glucose) is a stable isotopic tracer administered parenterally in healthy volunteers, obese or diabetic patients in clinical trial to study glucose metabolism during euglycemic hyperinsulinemic clamps. In accordance with the Health Authorities on drug safety, we evaluated the pharmaceutical quality of this preparation for biomedical research with a stability study. METHODS: After pharmaceutical qualification of the raw material, the [6,6-(2)H(2)]-glucose was dissolved in water for injection, then sterile, filtered under positive pressure of nitrogen and then autoclaved. Two batch products (500mg/10mL and 2g/15mL) were sampled to evaluate glucose alteration, isotope shift, limpidity, apyrogenicity and sterility at regular intervals for 2 years. Deuterated glucose solutions were stored in the dark, at +2°C+8°C, in type II glass bottles. RESULTS: Neither significant decrease of glucose concentration nor pH variation were observed for 2 years. The 5-hydroxymethylfurfural concentration was below the human harmful levels, attesting a non-generation of metabolites during autoclaving. Isotopic enrichment higher than 99% reflected the stability of deuterated label on the 6-carbon of glucose molecules. The non-visible particle concentration below the minimal permissible concentration tolerated by the European Pharmacopoeia and the absence of bacterial endotoxin and bacterial growth attested limpidity, apyrogenicity and sterility of the [6,6-(2)H(2)]-glucose solutions. CONCLUSION: After the 2-year study, 500mg/10mL and 2g/15mL deuterated glucose solutions stored in the dark at +2°C+8°C were stable in aqueous solution, allowing to ensure safety administration for human clinical trials using euglycemic hyperinsulinemic clamps.


Assuntos
Glucose/normas , Resistência à Insulina/fisiologia , Compostos Radiofarmacêuticos/normas , Ensaios Clínicos como Assunto , Deutério , Composição de Medicamentos , Embalagem de Medicamentos , Estabilidade de Medicamentos , Armazenamento de Medicamentos , Filtração , Técnica Clamp de Glucose , Concentração de Íons de Hidrogênio , Indicadores e Reagentes , Infusões Parenterais , Reprodutibilidade dos Testes , Soluções/normas , Esterilização
11.
Eur J Endocrinol ; 165(1): 151-9, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21490123

RESUMO

UNLABELLED: OBJECTVIE: In the elderly, vitamin D deficit, low calcium intake, and impaired bone microarchitecture are associated with higher risk of hip fracture. We assessed the association of bone microarchitecture with calcium intake and serum concentrations of 25-hydroxycholecalciferol (25OHD) and parathyroid hormone (PTH) in men. DESIGN: Cross-sectional analysis was performed in 1064 men aged 20-87 years not taking vitamin D or calcium supplements. METHODS: Daily calcium intake was assessed using a food frequency questionnaire. Bone microarchitecture was assessed at distal radius and tibia by high-resolution peripheral quantitative computed tomography. We measured serum and urinary levels of biochemical bone turnover markers (BTMs). Statistical models were adjusted for age, weight, height, and glomerular filtration rate. RESULTS: In 500 men aged <65 years, lower 25OHD levels and low calcium intake were associated with lower trabecular volumetric bone mineral density (Dtrab) at the distal tibia, due to lower trabecular number (Tb.N). Low calcium intake was associated with lower cortical thickness (Ct.Th). Higher PTH level was associated with higher BTM levels. In 563 men aged ≥65 years, the highest PTH quartile was associated with lower Ct.Th (tibia), lower Dtrab (both sites), and lower Tb.N (radius) compared with the lowest quartile. Low calcium intake was associated with lower Tb.N and more heterogenous trabecular distribution. BTM positively correlated with the PTH concentration. CONCLUSION: In older men, elevated PTH concentration is associated with high bone turnover, poor trabecular microarchitecture (radius and tibia), and, at the distal tibia, lower Ct.Th. Low calcium intake is associated with lower Tb.N and more heterogenous trabecular distribution.


Assuntos
Densidade Óssea , Cálcio da Dieta/administração & dosagem , Hormônio Paratireóideo/sangue , Rádio (Anatomia)/diagnóstico por imagem , Tíbia/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Calcifediol/sangue , Estudos de Coortes , Fraturas do Quadril/prevenção & controle , Humanos , Masculino , Pessoa de Meia-Idade , Osteocalcina/sangue , Estudos Prospectivos , Tomografia Computadorizada por Raios X
12.
Nitric Oxide ; 23(3): 194-8, 2010 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-20547233

RESUMO

An overwhelming nitric oxide (NO) production is a crucial step in the circulatory events as well as in the cellular alterations taking place in septic shock. However, evidences of this role arise from studies assessing the NO production on an intermittent basis precluding any clear evaluation of temporal relationship between NO production and circulatory alterations. We evaluated this relationship by using a NO specific electrode allowing a continuous measurement of NO production. Septic shock was induced by a cecal ligation and puncture (CLP) in a first group of anesthetized rats. After the same CLP, a second group received a selective iNOS inhibitor (L-NIL). Control rats were sham operated or sham operated with L-NIL administration. While NO concentration was measured every 2 min by a NO-sensitive electrode over 7h following CLP, the liver microcirculation was recorded by a laser-Doppler flowmeter. CLP induced a severe septic shock with hypotension occurring at a mean time of 240 min after CLP. At the same time, an increase in liver NO concentration was observed, whereas a decrease in microvascular liver perfusion was noted. In the septic shock group, L-NIL administration induced an increase in arterial pressure whereas the liver NO concentration returned to baseline values. In addition, shock groups experienced an increase in iNOS mRNA. These data showed a close temporal relationship between the increase in liver NO concentration and the microvascular alteration taking place in the early period of septic shock induced by CLP. The iNOS isoform is involved in this NO increase.


Assuntos
Ceco/cirurgia , Fígado/metabolismo , Óxido Nítrico/análise , Punções , Choque Séptico/fisiopatologia , Animais , Modelos Animais de Doenças , Eletrodos , Ligadura , Masculino , Óxido Nítrico/biossíntese , Peritonite/fisiopatologia , Ratos , Ratos Wistar , Fatores de Tempo
13.
Ann Biol Clin (Paris) ; 66(6): 647-55, 2008.
Artigo em Francês | MEDLINE | ID: mdl-19091664

RESUMO

Seven hospital-based glucose monitoring systems (meters) were evaluated with particular attention to those analytical interferences encountered in intensive care patients. Imprecision differed little between meters and remained altogether within acceptable limits. Inaccuracy, as measured by comparison with a hexokinase method presented with significant differences, yet without exceeding acceptable limits either. All meters but one showed an important bias when hematocrit departed from the reference interval. Two meters would not distinguish maltose from glucose. Three showed an important positive bias in the presence of acetaminophen and four a comparable bias in the presence of ascorbate. Only one meter was unaffected by both such exogenous interferences and hematocrit variations, owing to built-in hematocrit and electrochemical blank measuring devices. This meter also showed narrowest correlation with hexokinase methods. At a time when intensive care patients are being submitted to ever tighter glycemic control, it is desirable and our results show that it is now possible to tighten accordingly the acceptability criteria of glucose meters used to this end.


Assuntos
Glicemia/análise , Hematócrito , Sistemas Automatizados de Assistência Junto ao Leito , Acetaminofen/farmacologia , Ácido Ascórbico/farmacologia , Análise Química do Sangue , Glicemia/efeitos dos fármacos , Eletroquímica , Hexoquinase/sangue , Humanos , Unidades de Terapia Intensiva , Maltose/sangue , Valores de Referência , Reprodutibilidade dos Testes
14.
Br J Anaesth ; 100(1): 55-65, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17982168

RESUMO

BACKGROUND: We tested the hypothesis that sodium nitroprusside (SNP) might improve the impairment of hepatosplanchnic microcirculatory blood flow (MBF) in septic shock. METHODS: Fourteen pigs were anaesthetized and their lungs mechanically ventilated. Sepsis was induced with i.v. infusion of live Pseudomonas aeruginosa [1x10(8) colony forming units (CFU) ml(-1) kg(-1)] for 1 h. Sixty minutes later, the animals received in a random succession either SNP or normal saline for 30 min. Mean arterial pressure (MAP), cardiac index (CI), mean pulmonary artery pressure (MPAP), carbon dioxide tension of the ileal mucosa (PCO2; by gas tonometry), ileal mucosal and hepatic MBF by laser Doppler flowmetry, blood gases, and lactates were assessed before, during administration, and 30 min after discontinuing the test drug. RESULTS: Bacterial infusion promoted hypodynamic shock (MAP -18%, CI -33%, ileal MBF -19%, and hepatic MBF -27%), which was converted to normodynamic shock by resuscitation. During SNP infusion, ileal mucosal MBF significantly increased (+19%) compared with control (P = 0.033). Although hepatic MBF increased (+42% from baseline), this did not differ from control. In order to maintain a constant central venous pressure and MAP, fluid loading and norepinephrine (P < 0.01) were increased. Acid-base status was not altered by SNP. CONCLUSIONS: In a resuscitated porcine model of the early phase of septic shock, SNP improved ileal mucosal MBF but required a concomitant increase in fluid and norepinephrine supplements to maintain constant systemic haemodynamic parameters.


Assuntos
Nitroprussiato/farmacologia , Choque Séptico/fisiopatologia , Circulação Esplâncnica/efeitos dos fármacos , Vasodilatadores/farmacologia , Equilíbrio Ácido-Base/efeitos dos fármacos , Animais , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos/métodos , Feminino , Íleo/irrigação sanguínea , Mucosa Intestinal/irrigação sanguínea , Circulação Hepática/efeitos dos fármacos , Microcirculação/efeitos dos fármacos , Fluxo Sanguíneo Regional/efeitos dos fármacos , Respiração Artificial , Choque Séptico/terapia , Sus scrofa
15.
Ann Biol Clin (Paris) ; 65(1): 33-40, 2007.
Artigo em Francês | MEDLINE | ID: mdl-17264037

RESUMO

NADPH oxidase (NOX) is a multimeric enzyme including a catalytic unit, gp91(phox), and several regulating subunits: p22(phox), p40(phox), p47(phox), p67(phox). This enzyme, also known as flavocytochrome b(588), is responsible for a deliberate production of superoxyde anion (O2*-). This enzyme, initially described in polynuclear neutrophils (NOX 2), belongs to a complex family of multimeric isoenzymes whose members are present in many cell types. NOXs are generally associated to cell signaling and they seem involved in physiological phenomena (vascular reactivity, proliferation and cellular migration...) as well as in many diseases. Lipids in general and poly unsaturated fatty acids (PUFA) in particular are able to modulate the activity of NOX in many models. With our fibroblastic model, we show that only arachidonic acid (AA) is able to activate the enzyme directly whereas many PUFA are able to induce a production of reactive oxygen species (ERO). Moreover the decrease of ERO production and NOX activity in fibroblasts triggered by PUFA does not depend on SOD activity but the time course of this decrease is associated with the expression of heme oxygenase 1 (HO-1). Besides a regulation by protein subunits, we propose, according to this model, a loop of regulation of NOX activity including a stimulation by lipids associated with an inhibition by HO-1. Thus, lipids, by interaction with phospholipase A2, release arachidonic acid which stimulates NOX, amplifying superoxyde anion production. This oxygen species may induce redox-sensitive gene transcription such as HO-1. Consequently this enzyme inhibits NOX activity and limits superoxyde anion production by heme degradation and CO production.


Assuntos
Ácidos Graxos Insaturados/farmacologia , NADPH Oxidases/metabolismo , Células Cultivadas , Fibroblastos/metabolismo , Citometria de Fluxo , Heme Oxigenase-1/metabolismo , Humanos , Espécies Reativas de Oxigênio/metabolismo
16.
Br J Anaesth ; 97(2): 137-46, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16613926

RESUMO

BACKGROUND: Direct evidence of nitric oxide (NO) involvement in the regulation of hepatic microcirculation is not yet available under physiological conditions nor in haemorrhagic shock. METHODS: A laser Doppler flowmetry was used to measure liver perfusion index and a specific NO-sensitive electrode was inserted into liver parenchyma of anaesthetized rabbits. Hepatic autoregulation during moderate hypovolaemia {mean arterial pressure at 50 mm Hg without liver perfusion alteration; blood withdrawal 17.7 (4.2) ml [mean (SD)]} or haemorrhagic shock [mean arterial pressure at 20 mm Hg associated with liver perfusion impairment and lactic acidosis; blood withdrawal 56.0 (6.8) ml] were investigated over 60 min and were followed by a rapid infusion of the shed blood. Involvement of NO synthases was evaluated using a non-specific inhibitor, NAPNA (Nomega-nitro-L-arginine P-nitro-anilide). RESULTS: In the autoregulation group, a decrease [30.0 (4.0) mm Hg] of mean arterial pressure did not alter liver perfusion index, whereas the liver NO concentration increased and reached a plateau [125 (10)%; compared with baseline; P<0.05]. This NO concentration was reduced to zero by the administration of NO synthase inhibitor. Haemorrhagic shock led to a rapid decrease in liver perfusion index [60 (7)%; compared with baseline; P<0.05] before an immediate and continuous increase in NO concentration [250 (50)%; compared with baseline; P<0.05]. Infusion of NO inhibitor before haemorrhagic shock reduced the NO concentration to zero and hepatic perfusion by 60 (8)% (P<0.05) of the baseline. Mean arterial pressure increased simultaneously. In these animals, during haemorrhage, a continuous increase in NO concentration still occurred and liver perfusion slightly increased. In all groups but NAPNA+haemorrhagic shock, blood replacement induced recovery of baseline values. CONCLUSIONS: NO plays a physiological role in the liver microcirculation during autoregulation. Its production is enzyme-dependent. Conversely, haemorrhagic shock induces a rapid increase in hepatic NO that is at least partially enzyme-independent.


Assuntos
Homeostase/fisiologia , Fígado/irrigação sanguínea , Óxido Nítrico/biossíntese , Choque Hemorrágico/fisiopatologia , Anilidas/administração & dosagem , Animais , Arginina/administração & dosagem , Arginina/análogos & derivados , Pressão Sanguínea/fisiologia , Dióxido de Carbono/fisiologia , Modelos Animais de Doenças , Artéria Hepática/fisiologia , Infusões Intravenosas , Fígado/fisiologia , Microcirculação , Modelos Animais , Óxido Nítrico/análise , Óxido Nítrico Sintase/antagonistas & inibidores , Oxigênio/fisiologia , Coelhos , Choque Hemorrágico/metabolismo
18.
Br J Anaesth ; 89(2): 231-6, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12378658

RESUMO

BACKGROUND: In several lung diseases, oxidative stress can be demonstrated. This has not been shown in patients with ventilator-associated pneumonia (VAP). METHODS: We studied plasma and bronchoalveolar lavage (BAL) samples for markers of oxidative stress, taken from patients with VAP. Seventy-eight patients likely to have VAP and 10 patients who were not suspected of having VAP were studied prospectively. A diagnosis of VAP was based on a positive quantitative mini-lavage culture of > or = 10(3) colony-forming units per ml. Blood and BAL samples were collected and analysed for thiobarbituric acid reactant substances (TBARS) and antioxidant activity. RESULTS: Plasma and alveolar TBARS increased significantly in patients who developed VAP compared with those who did not, by 43% and 259% respectively. Red cells and alveolar glutathione peroxidase concentrations (antioxidant activity) were lower in those with VAP compared with the non-VAP group, by 43% and 68% respectively. No significant differences were found for serum superoxide dismutase activity. Significant differences were found for alveolar glutathione peroxidase concentrations over time in the VAP group. No significant differences between survivors and non-survivors were found in the blood or BAL assays, in patients with VAP. CONCLUSIONS: VAP is associated with evidence of early oxidative stress in the alveolar fluid and blood.


Assuntos
Estresse Oxidativo/fisiologia , Pneumonia/fisiopatologia , Alvéolos Pulmonares/fisiopatologia , Respiração Artificial/efeitos adversos , Adulto , Idoso , Idoso de 80 Anos ou mais , Lavagem Broncoalveolar , Feminino , Glutationa Peroxidase/análise , Humanos , Masculino , Pessoa de Meia-Idade , Pneumonia/sangue , Pneumonia/etiologia , Alvéolos Pulmonares/metabolismo , Superóxido Dismutase/análise , Substâncias Reativas com Ácido Tiobarbitúrico/análise
20.
Ann Biol Clin (Paris) ; 59(5): 559-65, 2001.
Artigo em Francês | MEDLINE | ID: mdl-11602386

RESUMO

Nitrite (NO2-) and nitrate (NO3-) concentrations are usually measured as a marker of NO metabolism. Indeed, this radical plays an important role in a lot of pathological processes. The aim of this study was to validate and standardize a method for the quantification of these two metabolites in serum. The most commonly method involved to determine nitrite and nitrate is the Griess reaction. From the different methods which are reported in literature, we tested several parameters to define operating conditions: the samples were deproteinized with zinc sulfate and reduced with cadmium granules. Analytical recovery of NO3- added to serum samples after reduction was 99.6% +/- 3.2% (n = 4). Within-run precision was 6.1% (n = 17) and between-day precision was 6.6% (n = 12). Usual values were determined from healthy fasted subjects: the mean concentration of NO2- and NO3- was 47.8 muM +/- 15.7 muM (n = 25). The detection limit of the assay was 1.3 muM and the quantitation limit was 2.5 muM. We tested also an HPLC method. However, it was not possible to use it from a biological matrice.


Assuntos
Nitratos/sangue , Nitritos/sangue , Análise de Variância , Cádmio , Cromatografia Líquida de Alta Pressão , Jejum , Humanos , Modelos Lineares , Modelos Químicos , Nitrato Redutase , Nitrato Redutases , Substâncias Redutoras , Temperatura , Fatores de Tempo , Sulfato de Zinco
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...