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1.
Genet Med ; 23(9): 1604-1615, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34040193

RESUMO

PURPOSE: Prolidase deficiency is a rare inborn error of metabolism causing ulcers and other skin disorders, splenomegaly, developmental delay, and recurrent infections. Most of the literature is constituted of isolated case reports. We aim to provide a quantitative description of the natural history of the condition by describing 19 affected individuals and reviewing the literature. METHODS: Nineteen patients were phenotyped per local institutional procedures. A systematic review following PRISMA criteria identified 132 articles describing 161 patients. Main outcome analyses were performed for manifestation frequency, diagnostic delay, overall survival, symptom-free survival, and ulcer-free survival. RESULTS: Our cohort presented a wide variability of severity. Autoimmune disorders were found in 6/19, including Crohn disease, systemic lupus erythematosus, and arthritis. Another immune finding was hemophagocytic lymphohistiocytosis (HLH). Half of published patients were symptomatic by age 4 and had a delayed diagnosis (mean delay 11.6 years). Ulcers were present initially in only 30% of cases, with a median age of onset at 12 years old. CONCLUSION: Prolidase deficiency has a broad range of manifestations. Symptoms at onset may be nonspecific, likely contributing to the diagnostic delay. Testing for this disorder should be considered in any child with unexplained autoimmunity, lower extremity ulcers, splenomegaly, or HLH.


Assuntos
Doença de Crohn , Úlcera da Perna , Deficiência de Prolidase , Criança , Pré-Escolar , Diagnóstico Tardio , Humanos , Fenótipo , Deficiência de Prolidase/diagnóstico , Deficiência de Prolidase/genética
2.
J Steroid Biochem Mol Biol ; 198: 105553, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31778802

RESUMO

21-hydroxylase deficiency, the most common enzyme defect associated with congenital adrenal hyperplasia (CAH) is characterized by an impairment of both aldosterone and cortisol biosynthesis. Close clinical and biological monitoring of Hydrocortisone (HC) and 9α-Fludrocortisone (FDR) replacement therapies is required to achieve an optimal treatment. As frequent and repeated reassessments of plasma steroids, 17-hydroxyprogesterone (17-OHP), androstenedione (Δ4-A) and testosterone (TESTO) is needed in childhood, urine steroid profiling could represent an interesting non-invasive alternative. We developed and validated a LC-MS/MS method for the measurement of 23-urinary mineralocorticoids, glucocorticoids and adrenal androgens. The usefulness of steroid profiling was investigated on single 08h00 am-collected spot urine for discriminating between 61 CAH patients and their age- and sex-matched controls. CAH patients were split into two groups according to their 08h00 am-plasma concentrations of 17-OHP: below (controlled patients, n = 26) and above 20 ng/mL (uncontrolled patients, n = 35). The lower limit of quantification and the wide analytical range allows to assay both free and total concentrations of the main urinary adreno-corticoids and their tetra-hydrometabolites. Extraction recoveries higher than 75% and intra-assay precision below 20% were found for most steroids. Urinary steroids upstream of the 21-hydroxylase defect were higher in uncontrolled CAH patients. Among CAH patients, plasma and urinary 17-OHP were closely correlated. As compared to controls, steroids downstream of the enzyme defect collapsed in CAH patients. This fall was more pronounced in controlled than in uncontrolled patients. Androgens (Δ4-A, TESTO and the sum etiocholanolone + androsterone) accumulated in uncontrolled CAH patients. A strong relationship was observed between plasma and urinary levels of androstenedione. Daily doses and urinary excretion of both FDR and HC were similar in both CAH groups. Urinary FDR was inversely related to the sodium-to-potassium ratio in urine. A partial least squares discriminant analysis model allowed to classify the patient's classes unaffected, controlled and un-controlled CAH patients based on urinary steroidomic profiles. Our LC-MS/MS method successfully established steroid profiling in urine and represents a useful and non-invasive tool for discriminating CAH patients according to treatment efficiency.


Assuntos
Hiperplasia Suprarrenal Congênita/urina , Androgênios/urina , Glucocorticoides/urina , Mineralocorticoides/urina , Adolescente , Criança , Pré-Escolar , Cromatografia Líquida/métodos , Feminino , Humanos , Masculino , Espectrometria de Massas em Tandem/métodos
3.
Ann Biol Clin (Paris) ; 75(4): 411-419, 2017 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-28751286

RESUMO

Troponin is a specific cardiac infarction isoform (TnIc, TnTc) and its determination is used for the diagnosis of myocardial infarction even with normal Electrocardiography. The increase of cardiac troponins occurs in a variety of clinical situations without an acute coronary syndrome (ACS), cardiologists and emergency physicians are often confronted with positive troponins that are difficult to interpret. Few data exist about the occurrence, the clinical characteristics and the predictive value in case of absence of ACS. The objective of this study is to present the main extracardiac causes responsible of the increase of TnIc. We present some clinical cases that illustrate this diagnostic problem. A troponin elevation is observed in myopericarditis, renal failure, heart failure, pulmonary embolism, septic shock, rhabdomyolysis, stroke and others where there is a myocardial damage unrelated to coronary occlusion. Many cases of false positives, which raise the possibility of analytical interferences, must be identified.


Assuntos
Síndrome Coronariana Aguda/sangue , Biomarcadores/sangue , Hipertensão/diagnóstico , Acidente Vascular Cerebral/diagnóstico , Troponina/sangue , Adulto , Diagnóstico Diferencial , Humanos , Hipertensão/sangue , Hipertensão/complicações , Masculino , Acidente Vascular Cerebral/sangue , Acidente Vascular Cerebral/complicações , Regulação para Cima
4.
J Clin Endocrinol Metab ; 100(11): 4074-81, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26348350

RESUMO

CONTEXT: The neonatal period, notably in preterm infants, is characterized by high sodium wasting, implying that aldosterone, the main hormone regulating sodium reabsorption, is unable to maintain sodium homeostasis. OBJECTIVE: This study sought to assess aldosterone secretion and action in neonates according to gestational age (GA). DESIGN AND SETTING: This was a multicenter prospective study (NCT01176162) conducted between 2011 and 2014 at five neonatology departments in France. Infants were followed during their first 3 months. PARTICIPANTS: The 155 newborns included were classified into three groups: Group 1 (n = 46 patients), <33 gestational weeks (GW); Group 2 (n = 67 patients), 33-36 GW; and Group 3 (n = 42 patients), ≥37 GW. MAIN OUTCOME MEASURES: Plasma aldosterone was measured in umbilical cord blood. Urinary aldosterone (UAldo) was assessed at day 0, day 3, month 1, and month 3 postnatal. The correlation between UAldo and the urinary Na/K ratio was determined as an index of renal aldosterone sensitivity. RESULTS: UAldo significantly increased with GA: from 8.8 ± 7.5 µg/mmol of creatinine (Group 1) to 21.1 ± 21.0 (Group 3) in correlation with plasma aldosterone levels in all groups (P < .001), demonstrating its reliability. The aldosterone/renin ratio significantly increased with GA, suggesting an aldosterone secretion defect in preterm infants. UAldo and urinary Na/K were correlated in very preterm but not in term neonates, consistent with very preterm neonates being renal-aldosterone sensitive and term neonates being aldosterone resistant. CONCLUSIONS: Very preterm infants have a previously unrecognized defective aldosterone secretion but conserved renal aldosterone sensitivity in the neonatal period, which modifies the current view of sodium balance in these infants and suggests alternative management approaches.


Assuntos
Aldosterona/fisiologia , Transdução de Sinais/fisiologia , Sódio/metabolismo , Adolescente , Adulto , Envelhecimento/metabolismo , Aldosterona/sangue , Aldosterona/urina , Peso ao Nascer , Eletrólitos/urina , Feminino , Sangue Fetal/química , Idade Gestacional , Homeostase , Humanos , Lactente Extremamente Prematuro , Recém-Nascido , Recém-Nascido Prematuro/metabolismo , Masculino , Pessoa de Meia-Idade , Gravidez , Estudos Prospectivos , Renina/sangue
6.
Int J Cardiol ; 166(1): 198-204, 2013 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-22104994

RESUMO

BACKGROUND: Copeptin, in combination with conventional troponin (cTn), has been suggested as a means of rapid rule out of the diagnosis of acute myocardial infarction (AMI). This study aims to assess the value of copeptin for rule out of AMI, according to the pre-test probability (PTP). METHODS: In a prospective multicentric study, we enrolled patients presenting into emergency departments with chest pain <6h, copeptin was measured, and PTP was quoted. The discharge diagnosis was adjudicated by 2 independent experts using all available data, including cTnI. RESULTS: 317 patients were included: 148 (46%) had low, 110 (35%) moderate and 59 (19%) high PTP. Final diagnosis was AMI in 45 patients (14%). Median copeptin level was higher in AMI patients compared with that in patients having other diagnoses (23.2 vs. 9.9 pmol/L, p=0.01). A copeptin level ≥10.7 pmol/L in combination with cTnI detected AMI with higher sensitivity than for cTnI alone (98 [87-100] vs. 71 [55-83] %, p=0.001), whatever the PTP. The negative predictive value of the combination copeptin+cTnI was increased, compared to that of cTnI alone (99 [97-100] vs. 95 [92-97] %, p<0.05). CONCLUSIONS: In triage of chest pain patients, the additional use of copeptin with conventional cTnI might allow a rapid and reliable rule out of the diagnosis of AMI regardless of the PTP.


Assuntos
Serviços Médicos de Emergência/métodos , Serviço Hospitalar de Emergência , Glicopeptídeos , Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio/metabolismo , Adulto , Idoso , Serviços Médicos de Emergência/normas , Serviço Hospitalar de Emergência/normas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/epidemiologia , Estudos Prospectivos , Precursores de Proteínas , Fatores de Tempo , Triagem/métodos , Triagem/normas , Troponina
7.
Shock ; 38(6): 592-7, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23042202

RESUMO

The objective of this study was to determine the predictive value of the renal resistive index (RI) and cystatin C values in serum (SCys) and urine (UCys) in the development of acute kidney injury (AKI) in critically ill patients with severe sepsis or polytrauma. This was a prospective, double-center, descriptive study. There were 58 patients with severe sepsis (n= 28) or polytrauma (n = 30). Renal resistive index, SCys, and UCys were measured within 12 h following admission (day 1 [D1]) to the intensive care unit. Renal function was assessed using the AKI network classification: On day 3 (D3), 40 patients were at stage 0 or 1, and 18 were at stage 2 or 3. Patients with AKI stage 2 or 3 had significantly higher RI (0.80 vs. 0.66, P < 0.0001), SCys (1.23 vs. 0.68 mg/L, P = 0.0002), and UCys (3.32 vs. 0.09 mg/L, P = 0.0008). They also had higher Simplified Acute Physiology Score II, arterial lactate level, and intensive care unit mortality. In multivariate analysis, an RI of greater than 0.707 on D1 was the only parameter predictive of the development of AKI stage 2 or 3 on D3 (P = 0.0004). In the subgroup of patients with AKI stage 2 or 3 on D1, RI remained the only parameter associated with persistent AKI on D3 (P = 0.016). In multivariate analysis comparing the predictive value of RI, SCys, and UCys, RI was the only parameter predictive of AKI stage 2 or 3 on D3. Renal resistive index seems to be a promising tool to assess the risk of AKI.


Assuntos
Injúria Renal Aguda/sangue , Injúria Renal Aguda/fisiopatologia , Cistatina C/sangue , Testes de Função Renal , Traumatismo Múltiplo/sangue , Traumatismo Múltiplo/fisiopatologia , Sepse/sangue , Sepse/fisiopatologia , Injúria Renal Aguda/etiologia , Injúria Renal Aguda/mortalidade , Injúria Renal Aguda/terapia , Adulto , Idoso , Feminino , Mortalidade Hospitalar , Humanos , Unidades de Terapia Intensiva , Masculino , Pessoa de Meia-Idade , Traumatismo Múltiplo/complicações , Traumatismo Múltiplo/mortalidade , Traumatismo Múltiplo/terapia , Valor Preditivo dos Testes , Estudos Prospectivos , Sepse/mortalidade , Sepse/terapia
8.
Eur J Pharmacol ; 691(1-3): 110-7, 2012 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-22683876

RESUMO

Local anesthetic toxicity includes a decrease in ventricular conduction velocity and a decrease in myocardial contractile force. We tested the hypothesis that, like conduction, contraction was stereoselectively impaired by bupivacaine. We compared R(+) and S(-) bupivacaine to S(+) and R(-) RAC 109 in order to study the effects of hydrophobicity and ionization. We measured the changes in QRS duration and developed pressure in isolated perfused rabbit hearts. Binding of bupivacaine and RAC 109 to the ryanodine receptor was measured. The effect on cell shortening and relenghtening was measured on isolated rabbit cardiomyocytes. A mixed-effect pharmacodynamic model was used. The decrease in conduction velocity induced by the molecules was markedly stereospecific. All local anesthetics decreased ventricular velocity in a stereospecific manner with a RAC I(+)/II(-) and bupivacaine R(+)/S(-) potency ratio of maximum effect of 1.7 and 2.25 respectively. Contractility decreased in a dose dependent manner but this negative inotropic effect was not stereospecific with a C50 (concentration leading to half maximum effect) of 30 and 23 µM for RAC and bupivacaine respectively. The two drugs exhibited two-site binding to ryanodyne that may partly explain the observed effect. An effect on relaxation was observed only at very high concentrations. In conclusion, bupivacaine, a long acting local anesthetic, decreases ventricular conduction in a stereospecific manner, and decreases contractility non-stereospecifically.


Assuntos
Anestésicos Locais/efeitos adversos , Sistema de Condução Cardíaco/efeitos dos fármacos , Contração Miocárdica/efeitos dos fármacos , Animais , Bupivacaína/efeitos adversos , Sistema de Condução Cardíaco/citologia , Sistema de Condução Cardíaco/fisiologia , Lidocaína/efeitos adversos , Masculino , Miócitos Cardíacos/citologia , Miócitos Cardíacos/efeitos dos fármacos , Naftalenos/efeitos adversos , Pirrolidinonas/efeitos adversos , Coelhos , Rianodina/metabolismo , Retículo Sarcoplasmático/efeitos dos fármacos , Retículo Sarcoplasmático/metabolismo
10.
Am J Emerg Med ; 30(8): 1378-84, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22169585

RESUMO

BACKGROUND: In combination with cardiac troponin, heart-type fatty acid binding protein (h-FABP)-a biomarker of myocardial necrosis-offers the possibility of rapidly eliminating the diagnosis of acute myocardial infarction (AMI). OBJECTIVE: The main objective of this study was to assess the incremental value of h-FABP to cardiac troponin for a rapid elimination of AMI, according to the pretest probability (PTP) of AMI. METHODS: In consecutive patients presenting to emergency departments (ED) with chest pain less than 6 hours suggestive of AMI, h-FABP levels were measured, blinded to the ED physicians, who were asked to quote the PTP of AMI. The discharge diagnosis was adjudicated by 2 independent experts, blind to the h-FABP level. RESULTS: Three hundred seventeen patients (mean age of 57 years) were included in whom 149 had (47%) low, 117 (37%) moderate, and 51 (16%) high PTP. The final diagnosis was AMI in 45 patients (14%), including 16 STEMIs (5%). The negative predictive value for diagnostic elimination of AMI of an h-FABP less than 3 µg/L, combined with a negative cTnI was not higher than that of cardiac troponin I (cTnI) alone (96% [95% confidence interval, 93%-98%] vs 95% [93%-98%]), regardless of the PTP). Even in the low-PTP group, we did not demonstrate a significant improvement in negative predictive value with the addition of h-FABP, compare with that of cTnI alone (100% [97%-100%] vs 99% [96%-100%]). CONCLUSION: In triage of patients with chest pain, use of h-FABP does not provide useful additional information to cTnI for excluding the diagnosis of ST-elevation myocardial infarction and non-ST-elevation myocardial infarction diagnosis, whatever the PTP.


Assuntos
Síndrome Coronariana Aguda/sangue , Proteínas de Ligação a Ácido Graxo/sangue , Síndrome Coronariana Aguda/diagnóstico , Idoso , Dor no Peito/sangue , Dor no Peito/diagnóstico , Serviço Hospitalar de Emergência , Proteína 3 Ligante de Ácido Graxo , Feminino , Taxa de Filtração Glomerular , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/sangue , Infarto do Miocárdio/diagnóstico , Troponina I/sangue
11.
FEBS Lett ; 585(17): 2703-8, 2011 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-21820436

RESUMO

A strict control of endolymph composition (high potassium, low sodium fluid) and volume is instrumental for a proper functioning of the inner ear. Alteration of endolymph homeostasis is proposed in the pathogenesis of Menière's disease. However, the mechanisms controlling endolymph secretion remain elusive. By using the vestibular EC5v cells, we provide evidence for the presence of vasopressin, catecholamine and purinergic signaling pathways, coupled to adenylate cyclase, phosphoinositidase C and Ca(2+) activation. We demonstrate that vasopressin and catecholamines stimulate while ATP inhibits apical potassium secretion by EC5v cells. These results open new interesting perspectives for the management of inner ear diseases.


Assuntos
Trifosfato de Adenosina/farmacologia , Catecolaminas/farmacologia , Orelha Interna/efeitos dos fármacos , Orelha Interna/metabolismo , Potássio/metabolismo , Vasopressinas/farmacologia , Adenilil Ciclases/metabolismo , Animais , Western Blotting , Sinalização do Cálcio/efeitos dos fármacos , Linhagem Celular , AMP Cíclico/metabolismo , Orelha Interna/citologia , Camundongos , Diester Fosfórico Hidrolases/metabolismo , Receptores Purinérgicos P2Y/metabolismo , Receptores de Vasopressinas/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
12.
Crit Care ; 15(3): R147, 2011 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-21663627

RESUMO

INTRODUCTION: Recently, newer assays for cardiac troponin (cTn) have been developed which are able to detect changes in concentration of the biomarker at or below the 99th percentile for a normal population. The objective of this study was to compare the diagnostic performance of a new high-sensitivity troponin T (HsTnT) assay to that of conventional cTnI for the diagnosis of acute myocardial infarction (AMI) according to pretest probability (PTP). METHODS: In consecutive patients who presented to our emergency departments with chest pain suggestive of AMI, levels of HsTnT were measured at presentation, blinded to the emergency physicians, who were asked to estimate the empirical PTP of AMI. The discharge diagnosis was adjudicated by two independent experts on the basis of all available data. RESULTS: A total of 317 patients were included, comprising 149 (47%) who were considered to have low PTP, 109 (34%) who were considered to have moderate PTP and 59 (19%) who were considered to have high PTP. AMI was confirmed in 45 patients (14%), 22 (9%) of whom were considered to have low to moderate PTP and 23 (39%) of whom were considered to have high PTP (P < 0.001). In the low to moderate PTP group, HsTnT levels ≥ 0.014 µg/L identified AMI with a higher sensitivity than cTnI (91%, 95% confidence interval (95% CI) 79 to 100, vs. 77% (95% CI 60 to 95); P = 0.001), but the negative predictive value was not different (99% (95% CI 98 to 100) vs. 98% (95% CI 96 to 100)). There was no difference in area under the receiver operating characteristic (ROC) curve between HsTnT and cTnI (0.93 (95% CI 0.90 to 0.98) vs. 0.94 (95% CI 0.88 to 0.97), respectively). CONCLUSIONS: In patients with low to moderate PTP of AMI, HsTnT is slightly more useful than cTnI. Our results confirm that the use of HsTnT has a higher sensitivity than conventional cTnI.


Assuntos
Serviço Hospitalar de Emergência/normas , Infarto do Miocárdio/sangue , Infarto do Miocárdio/diagnóstico , Troponina/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/epidemiologia , Estudos Prospectivos
13.
Rejuvenation Res ; 14(4): 353-63, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21548759

RESUMO

It has been suggested that increasing age is correlated with an acceleration of the progression of liver fibrosis induced by various agents, such as hepatitis C virus or chronic alcohol consumption. However, the cellular and molecular changes underlying this predisposition are not entirely understood. In the context of an aging population, it becomes challenging to decipher the mechanisms responsible for this higher susceptibility of older individuals to this acquired liver disorder. To address this issue, we induced liver fibrosis by carbon tetrachloride (CCl(4)) chronic administration to 8-week- and 15-month-old mice. We confirmed that susceptibility to fibrosis development increased with age and showed that aging did not affect fibrosis resolution capacity. We then focused on the impairment of hepatocyte proliferation, oxidative stress, and inflammation as potential mechanisms accelerating the development of fibrosis in the elderly. We detected no inhibition of hepatocyte proliferation after CCl(4) injury in 15-month-old mice, whereas it was inhibited after a partial hepatectomy. Finally, we observed that, in a context in which liver oxidative stress was not differentially increased in both experimental groups, there was a higher recruitment of inflammatory cells, including mostly macrophages and lymphocytes, oriented toward a T helper 2 (T(H)2) response in older mice. Our data show that in conditions of equivalent levels of oxidative stress and maintained hepatocyte proliferative capacity, an increased inflammatory reaction mainly composed of CD4(+) lymphocytes and macrophages expressing T(H)2 cytokines is the main factor involved in the higher susceptibility to fibrosis with increasing age.


Assuntos
Envelhecimento/patologia , Suscetibilidade a Doenças , Inflamação/complicações , Inflamação/patologia , Cirrose Hepática/complicações , Cirrose Hepática/patologia , Animais , Tetracloreto de Carbono , Proliferação de Células , Doença Crônica , Hepatócitos/patologia , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Necrose , Estresse Oxidativo
14.
Biochimie ; 92(9): 1130-7, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20685376

RESUMO

An investigation of radiation-induced oxidation of aqueous bovine serum albumin (BSA) in the presence of linoleate (LH) at pH 10.5 has been carried out in order to better understand the respective oxidative processes involved in both lipid and protein phases. Solutions containing BSA (15 micromol L(-1)) and linoleate (15-600 micromol L(-1)) below the critical micellar concentration (cmc=2000 micromol L(-1)), have been irradiated by gamma-rays (137Cs) at radiation doses ranging from 10 to 400 Gy (dose rate 9.5 Gy min(-1)). It can be noticed that, in the absence of BSA, the main hydroperoxides formed from HO*-induced linoleate oxidation below the cmc, do not exhibit a conjugated dienic structure. This was also verified in the presence of BSA. Selected chemical markers of oxidation have been monitored: non-conjugated dienic hydroperoxides and conjugated dienes (without hydroperoxide function) for linoleate oxidation, and carbonyl groups for BSA oxidation. We have shown that for the lowest linoleate concentration (15 micromol L(-1)) in the presence of BSA (15 micromol L(-1)), the formation of conjugated dienes was not observed, meaning that LH was not exposed to HO* radicals attack. However, non-conjugated dienic lipid hydroperoxides were simultaneously detected, indicating that LH was secondarily oxidised by BSA oxidised species. Moreover, the oxidation of linoleate was found to be enhanced by the presence of BSA. For the highest linoleate concentration (600 micromol L(-1)), the expected protection of BSA by LH was not observed, even if LH monomers were responsible for the total scavenging of HO* radicals. In this latter case, the formation of non-conjugated dienic lipid hydroperoxides was lower than expected. Those results showed that BSA was not oxidised by the direct action of HO* radicals but was undergoing a secondary oxidation by non-dienic lipid hydroperoxides and/or lipid radical intermediates, coming from the HO*-induced linoleate oxidation.


Assuntos
Radicais Livres/química , Radical Hidroxila/química , Ácido Linoleico/química , Soroalbumina Bovina/química , Animais , Bovinos , Concentração de Íons de Hidrogênio , Oxirredução
15.
Pediatr Res ; 66(3): 323-8, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19542911

RESUMO

In the neonatal period, the human kidney is characterized by an impaired ability to regulate water and sodium homeostasis, resembling partial aldosterone resistance. The aim of our study was to assess this hormonal insensitivity in newborn infants and to determine its relationship with neonatal sodium handling. We conducted a prospective study in 48 healthy newborns and their mothers. Aldosterone, renin, and electrolyte concentrations were measured in umbilical cords and in maternal plasma. Urinary aldosterone concentrations and sodium excretion were determined at urination within 24 h after birth. A significant difference was observed between aldosterone and renin levels in newborn infants compared with their mothers (817 +/- 73 versus 575 +/- 55 pg/mL and 79 +/- 10 versus 15 +/- 2 pg/mL, respectively, p < 0.001). This hyperactivation of the renin-angiotensin-aldosterone system was associated with hyponatremia and hyperkalemia in the newborn infants, and high urinary sodium loss, consistent with a partial aldosterone resistance at birth. Unlike plasma aldosterone, urinary aldosterone concentration was found highly correlated with plasma potassium concentrations, thus representing the best index for accurate evaluation of mineralocorticoid sensitivity. Our study represents a comprehensive characterization of the renin-aldosterone axis in newborn infants and provides evidence for physiologic partial aldosterone resistance in the neonatal period.


Assuntos
Aldosterona/sangue , Recém-Nascido/metabolismo , Renina/sangue , Adolescente , Adulto , Aldosterona/urina , Feminino , Humanos , Hiperaldosteronismo/metabolismo , Pessoa de Meia-Idade , Mineralocorticoides/sangue , Potássio/sangue , Potássio/urina , Estudos Prospectivos , Sistema Renina-Angiotensina/fisiologia , Sódio/sangue , Sódio/urina , Equilíbrio Hidroeletrolítico , Adulto Jovem
16.
Metabolism ; 56(3): 308-13, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17292717

RESUMO

Beyond its antihyperglycemic action, the antidiabetic oral drug metformin possesses antioxidant properties that may contribute to improve the cardiovascular deleterious effects of the diabetic disease. We explored whether metformin could modulate the redox-sensible expression of receptor for advanced glycation end products (RAGE) and lectin-like oxidized receptor 1 (LOX-1), 2 endothelial membrane receptors involved in the arterial endothelial dysfunction observed in diabetes. Bovine aortic endothelial cells, either unstimulated or activated by high levels of glucose (30 mmol/L) or advanced glycation end products, were incubated for 72 hours with metformin at therapeutically relevant concentrations (10(-5) to 5 x 10(-4) mol/L). The expressions of RAGE and LOX-1 were evaluated on cell extracts by Western blot analysis. Metformin was shown to reduce, in dose-dependent manner, such expression of the 2 receptors, both in stimulated (by either glucose or advanced glycation end products) and in unstimulated cells. The effect of metformin was associated with a decrease in intracellular reactive oxygen species as assessed using the 2',7'-dichlorodihydrofluorescein diacetate fluoroprobe. Taken together, our results suggest that the intracellular antioxidant properties of metformin may result in the inhibition of cell expression of both RAGE and LOX-1, possibly through a modulation of redox-sensible nuclear factors such as nuclear factor kappaB, that were shown to be involved in such receptor cell expression.


Assuntos
Células Endoteliais/efeitos dos fármacos , Hipoglicemiantes/farmacologia , Metformina/farmacologia , Receptores Imunológicos/análise , Receptores Depuradores Classe E/análise , Animais , Western Blotting , Bovinos , Células Cultivadas , Células Endoteliais/química , Células Endoteliais/metabolismo , Espécies Reativas de Oxigênio , Receptor para Produtos Finais de Glicação Avançada
17.
Anesth Analg ; 102(5): 1511-7, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16632835

RESUMO

Respiratory-related variabilities in stroke volume and arterial pulse pressure (Delta%Pp) are proposed to predict fluid responsiveness. We investigated the influence of tidal volume (Vt) and adrenergic tone on these variables in mechanically ventilated patients. Cyclic changes in aortic velocity-time integrals (Delta%VTI(Ao), echocardiography) and Delta%Pp (catheter) were measured simultaneously before and after intravascular volume expansion, and Vt was randomly varied below and above its basal value. Intravascular volume expansion was performed by hydroxyethyl starch (100 mL, 60 s). Receiver operating characteristic curves were generated for Delta%VTI(Ao), Delta%Pp and left ventricle cross-sectional end-diastolic area (echocardiography), considering the change in stroke volume after intravascular volume expansion (> or =15%) as the response criterion. Covariance analysis was used to test the influence of Vt on Delta%VTI(Ao) and Delta%Pp. Twenty-one patients were prospectively included; 9 patients (43%) were responders to intravascular volume expansion. Delta%VTI(Ao) and Delta%Pp were higher in responders compared with nonresponders. Predictive values of Delta%VTI(Ao) and Delta%Pp were similar (threshold: 20.4% and 10.0%, respectively) and higher than that of left ventricle cross-sectional end-diastolic area at the appropriate level of Vt. Delta%Pp was slightly correlated with norepinephrine dosage. Delta%Pp increased with the increase in the level of Vt both before and after intravascular volume expansion, contrasting with an unexpected stability of Delta%VTI(Ao). In conclusion, Delta%VTI(Ao) and Delta%Pp are good predictors of intravascular fluid responsiveness but the divergent evolution of these two variables when Vt was increased needs further explanation.


Assuntos
Estado Terminal/terapia , Hidratação/métodos , Volume de Ventilação Pulmonar/fisiologia , Adulto , Idoso , Pressão Sanguínea/fisiologia , Volume Sanguíneo/fisiologia , Estado Terminal/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Respiração Artificial/estatística & dados numéricos , Volume Sistólico/fisiologia
18.
Resuscitation ; 68(1): 127-33, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16219409

RESUMO

The influence of haemorrhage and resuscitation on Tumour Necrosis Factor (TNF) production by whole blood cultures under endotoxin (Escherichia coli LPS) stimulation was investigated in male BALB/c mice. Haemorrhagic shock was induced by removing 0.026 +/- 0.003 mL of blood/g via a cardiac puncture, resulting in a 50% decrease in arterial pressure and a metabolic adidosis. Animals were resuscitated successfully (normotensive) despite a residual base deficit and hyperlactatemia, 60 min after the haemorrhage by the restitution of shed blood volume (SBV) with or without an additional volume of crystalloid (Lactated Ringer's solution) equal to 50, 100 (isovolumetric resuscitation) or 200% of SBV. Pulmonary failure (hypoxia-hypercarbia) and myocardial injury (troponin I release) was observed in this last group. TNF production by whole blood cultures stimulated ex vivo by LPS was estimated 60 min after the end of resuscitation. Haemorrhage resulted in a 48-60% decrease in TNF production. This decrease so-called 'leukocyte deactivation' was not modified by the restitution of SBV with or without crystalloid except for isovolumetric resuscitation which resulted in the cytokine level returning to control in the absence of clear cardiopulmonary dysfunction. In the present murine model of haemorrhage, modifying resuscitation volume influences in vitro TNF production in whole blood cultures challenged by LPS.


Assuntos
Células Sanguíneas/metabolismo , Volume Sanguíneo , Ressuscitação , Choque Hemorrágico/sangue , Fator de Necrose Tumoral alfa/biossíntese , Anestésicos Inalatórios/farmacologia , Animais , Soluções Cristaloides , Técnicas In Vitro , Isoflurano/farmacologia , Soluções Isotônicas/administração & dosagem , Soluções Isotônicas/uso terapêutico , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Substitutos do Plasma/administração & dosagem , Lactato de Ringer , Choque Hemorrágico/terapia
19.
Liver Int ; 25(5): 946-53, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16162151

RESUMO

AIMS: Steatosis may increase oxidative stress, which is counteracted by cellular enzymatic (cytosolic and mitochondrial superoxide dismutases (Cu/Zn-SOD and Mn-SOD), glutathione peroxidase (GPx), catalase) and non-enzymatic antioxidant systems. We aimed to determine, in patients with non-alcoholic fatty liver disease (NAFLD), the level of antioxidant defenses (1) in liver biopsies, to demonstrate the existence of oxidative stress; (2) in erythrocytes and plasma, to determine whether their antioxidant defenses reflect liver oxidative stress. METHODS: Erythrocyte and plasma antioxidant defenses were prospectively studied in two groups of 16 patients: patients with NAFLD and controls. Liver biopsies were performed in eight NAFLD patients; liver antioxidant enzyme activities were measured and compared with those in 12 control livers used for transplantation. RESULTS: Cu/Zn-SOD, GPx and catalase activities were significantly higher in NAFLD livers than in controls whereas no significant differences were observed in Mn-SOD activity, and thiobarbituric acid-reactive substance (TBARS) concentration. No differences were observed in erythrocyte antioxidant enzyme activities (GPx, catalase, Cu/Zn-SOD), erythrocyte TBARS concentration, and plasma alpha-tocopherol concentration. CONCLUSIONS: Liver antioxidant enzyme activities were high in patients with NAFLD, reflecting an oxidative stress possibly involved in inflammation and fibrogenesis. However, erythrocyte and plasma antioxidant defenses did not reflect intrahepatic peroxidation.


Assuntos
Catalase/metabolismo , Fígado Gorduroso/enzimologia , Glutationa Peroxidase/metabolismo , Fígado/enzimologia , Superóxido Dismutase/metabolismo , Adulto , Idoso , Eritrócitos/enzimologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Espécies Reativas de Oxigênio
20.
Anesthesiology ; 101(6): 1262-8, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15564931

RESUMO

BACKGROUND: The incidence and significance of troponin I release and its mechanism are unknown in severe trauma patients. The characteristics of this release were prospectively studied in such patients and correlated with presence of shock, existence of myocardial contusion, and outcome. METHODS: During a 24-month period, serial electrocardiogram recordings and troponin I measurements were performed in all trauma patients admitted at a surgical intensive care unit. The diagnosis of a significant myocardial contusion was made on electrocardiographic criteria. According to the time course of troponin I, three groups of patients were defined a priori: very transient (/= 2 microg/l), and sustained (> 36 h) and significant release (troponin I > 2 microg/l). In the last group, coronary artery angiography was performed. RESULTS: The incidence of troponin I release was 12% (95% confidence interval [CI], 9.6-14.4%) in 728 patients. A significant myocardial contusion was found in 35 patients (5%; 95% CI, 3.4-6.6%) and may occur in the absence of chest trauma and without troponin I release. Sensitivity, specificity, and positive and negative predictive values of troponin I for the diagnosis of myocardial contusion were 63, 98, 40, and 98%, respectively. Troponin I release was observed in 54 early (> 48 h) survivors (7%; 95% CI, 5.6-9.6%) without preexisting coronary artery disease. A sustained and significant release of troponin I (17 patients) was frequently associated with chest trauma (82%) and constantly with electrocardiographic abnormalities. A coronary artery injury was found in 7 patients (2 major and 5 minor vascular injuries) (1% of the whole group; 95% CI, 0.4-2.0%). Mortality was similar in early survivors with (15%; 95% CI, 7-27%) or without (12%; 95% CI, 9-14%) troponin I release. The odds ratio for late mortality was 1.32 (95% CI, 0.61-2.85) in patients with troponin I release. CONCLUSIONS: Serial electrocardiogram recordings and troponin I assessments may be proposed for initial screening in high-risk trauma patients to detect anatomical cardiac injuries through the time course of circulating protein. Troponin I release does not have a prognosis value in trauma patients.


Assuntos
Miocárdio/metabolismo , Troponina I/metabolismo , Ferimentos e Lesões/diagnóstico , Ferimentos e Lesões/metabolismo , Acidentes por Quedas , Acidentes de Trânsito , Adulto , Idoso , Biomarcadores , Contusões/diagnóstico , Contusões/metabolismo , Contusões/mortalidade , Angiografia Coronária , Ecocardiografia , Eletrocardiografia , Feminino , Traumatismos Cardíacos/diagnóstico , Traumatismos Cardíacos/metabolismo , Traumatismos Cardíacos/mortalidade , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Choque/diagnóstico , Choque/metabolismo , Análise de Sobrevida , Sobreviventes/estatística & dados numéricos , Resultado do Tratamento , Troponina I/análise , Ferimentos e Lesões/mortalidade , Ferimentos não Penetrantes/diagnóstico , Ferimentos não Penetrantes/metabolismo , Ferimentos não Penetrantes/mortalidade
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