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1.
Transplant Direct ; 8(1): e1272, 2022 Jan.
Article de Anglais | MEDLINE | ID: mdl-34966842

RÉSUMÉ

BACKGROUND: Long-term cardiovascular (CV) events are a frequent cause of death and disability after liver transplant (LT). Although a more in-depth, risk-adapted control of CV risk factors may result in improved post-LT CV outcomes, an accurate stratification of the CV risk of LT recipients to better implement preventive strategies is lacking. Aortic pulse wave velocity (aPWV) is a surrogate of arterial stiffness that has been suggested as a biomarker of CV risk; it has never been evaluated in adult LT recipients. METHODS: In a single-center prospective study, we included 122 LT recipients at 12 (n = 39), 60 (n = 45), or 120 (n = 38) mo after LT. aPWV estimation by oscillometry, clinical assessment of CV risk factors, and CV risk estimation by standard clinical scores (systematic coronary risk evaluation and pooled cohort equation) were performed. The incidence of CV events during prospective follow-up was registered. RESULTS: aPWV was independently associated with age and the grade of control of blood pressure. After a median follow-up of 35 mo, 15 patients (12%) presented a CV event. Higher aPWV, diabetes, past or present smoking habit, previous CV events, lower eGFR, being in systematic coronary risk evaluation or pooled cohort equation high-risk groups, and higher levels of total cholesterol, LDL-cholesterol, creatinine, and triglycerides were associated with the incidence of CV events at univariate analysis; aPWV, past or present smoking habit, and triglycerides were independent predictors of CV events. CONCLUSIONS: According to our results, aPWV mirrors CV risk in LT recipients and thus may be a useful CV risk biomarker in this population. Considering these preliminary results, its accuracy in stratifying risk requires confirmation in further studies.

2.
Nephron ; 143(2): 128-132, 2019.
Article de Anglais | MEDLINE | ID: mdl-31394546

RÉSUMÉ

A 31-year-old woman presented at the emergency room after experiencing colic pain in the right iliac fossa for 5 days. She had previously consulted another center, where deterioration of renal function had been identified and abdominal computed tomography (CT) angiography had shown a dissection of the right renal artery, with areas suggestive of infarction in the right kidney, as well as an aneurysm in the left renal artery and a smaller left kidney. The patient had no relevant family or personal history except posttraumatic carotid-cavernous fistula in 2014, which had been treated with embolization. In our hospital, the patient was hypertensive and acute renal failure was confirmed, accompanied by an increase in lactate dehydrogenase and isomorphic microhematuria. After a new CT Scan, in addition to the lesions described in the renal arteries, another aneurysm in the splenic artery and an aneurysm of the right femoral artery were identified. Antihypertensive treatment was initiated with calcium antagonists and anticoagulation. Subsequent renal arteriography confirmed the dissection of the right renal artery, which could not be repaired, and a coated stent was placed in the left renal artery to exclude the aneurysm. The splenic artery lesion was treated 2 months later. The etiological diagnosis in this young woman was challenging. The presence of visceral aneurysms suggested a differential diagnosis comprising fibromuscular dysplasia, vasculitis, and collagenopathies. Using a multidisciplinary approach and directed anamnesis, the presence of frequent sprains, joint hypermobility, and skin fragility was confirmed. Blood immunology and CT angiography including the thoracic and cervical territories were normal. Echocardiography revealed tricuspid insufficiency. All these data suggested the presence of a collagen-like Ehlers-Danlos syndrome (vascular form). The diagnosis was confirmed by the genetic study, which showed a pathogenic mutation in the COL3A1 gene. Currently, the patient is asymptomatic with recovered renal function following treatment with a beta-blocker and antiplatelet therapy.


Sujet(s)
/diagnostic , Syndrome d'Ehlers-Danlos/diagnostic , Dysplasie fibromusculaire/diagnostic , Artère rénale , Adulte , /imagerie diagnostique , /génétique , Collagène de type III/génétique , Angiographie par tomodensitométrie , Analyse de mutations d'ADN , Diagnostic différentiel , Syndrome d'Ehlers-Danlos/imagerie diagnostique , Syndrome d'Ehlers-Danlos/génétique , Femelle , Humains , Artère rénale/imagerie diagnostique
3.
Am J Hypertens ; 31(12): 1293-1299, 2018 11 13.
Article de Anglais | MEDLINE | ID: mdl-30084975

RÉSUMÉ

BACKGROUND: Central blood pressure (BP) is considered as a better estimator of hypertension-associated risks than peripheral BP. We aimed to evaluate the association of 24-hour central BP, in comparison with 24-hour peripheral BP, with the presence of left ventricular hypertrophy (LVH), or diastolic dysfunction (DD). METHODS: The cross-sectional study consisted of 208 hypertensive patients, aged 57 ± 12 years, of which 34% were women. Office and 24-hour central and peripheral BP were measured by the oscillometric Mobil-O-Graph device. We performed echocardiography-Doppler measurements to calculate LVH and DD, defined as left atrium volume ≥34 ml/m2 or septal e' velocity <8 cm/s or lateral e' velocity <10 cm/s. RESULTS: Seventy-seven patients (37%) had LVH, and 110 patients (58%) had DD. Systolic and pulse BP estimates (office, 24-hour, daytime, and nighttime) were associated with the presence of LVH or DD, after adjustment for age, gender, and antihypertensive treatment, with higher odds ratios for ambulatory-derived values. The comparison between central and peripheral BP estimates did not reveal a statistically significant superiority of the former neither in multiple regression models with simultaneous adjustments nor in the comparison of areas under receiver-operating curves. Correlation coefficients of BP estimates with left ventricular mass, although numerically higher for central BP, did not significantly differ between central and peripheral BP. CONCLUSIONS: We have not found a significant better association of 24-hour central over peripheral BP, with hypertensive cardiac alterations, although due to the sample size, these results require further confirmation in order to assess the possible role of routine 24-hour central BP measurement.


Sujet(s)
Pression sanguine , Hypertension artérielle/complications , Hypertrophie ventriculaire gauche/étiologie , Dysfonction ventriculaire gauche/étiologie , Fonction ventriculaire gauche , Adulte , Sujet âgé , Surveillance ambulatoire de la pression artérielle/méthodes , Études transversales , Diastole , Échocardiographie-doppler pulsé , Femelle , Humains , Hypertension artérielle/diagnostic , Hypertension artérielle/physiopathologie , Hypertrophie ventriculaire gauche/imagerie diagnostique , Hypertrophie ventriculaire gauche/physiopathologie , Mâle , Adulte d'âge moyen , Oscillométrie , Facteurs de risque , Espagne , Facteurs temps , Dysfonction ventriculaire gauche/imagerie diagnostique , Dysfonction ventriculaire gauche/physiopathologie
4.
J Diabetes Res ; 2018: 6165303, 2018.
Article de Anglais | MEDLINE | ID: mdl-29854824

RÉSUMÉ

Urinary proteome was analyzed and quantified by tandem mass tag (TMT) labeling followed by bioinformatics analysis to study diabetic nephropathy (DN) pathophysiology and to identify biomarkers of a clinical outcome. We included type 2 diabetic normotensive non-obese males with (n = 9) and without (n = 11) incipient DN (microalbuminuria). Sample collection included blood and urine at baseline (control and DN basal) and, in DN patients, after 3 months of losartan treatment (DN treated). Urinary proteome analysis identified 166 differentially abundant proteins between controls and DN patients, 27 comparing DN-treated and DN-basal patients, and 182 between DN-treated patients and controls. The mathematical modeling analysis predicted 80 key proteins involved in DN pathophysiology and 15 in losartan effect, a total of 95 proteins. Out of these 95, 7 are involved in both processes. VCAM-1 and neprilysin stand out of these 7 for being differentially expressed in the urinary proteome. We observed an increase of VCAM-1 urine levels in DN-basal patients compared to diabetic controls and an increase of urinary neprilysin in DN-treated patients with persistent albuminuria; the latter was confirmed by ELISA. Our results point to neprilysin and VCAM-1 as potential candidates in DN pathology and treatment.


Sujet(s)
Albuminurie/urine , Néphropathies diabétiques/urine , Néprilysine/urine , Protéome/métabolisme , Molécule-1 d'adhérence des cellules vasculaires/urine , Sujet âgé , Marqueurs biologiques/urine , Diabète de type 2/urine , Femelle , Humains , Mâle , Adulte d'âge moyen , Protéomique , Examen des urines
5.
J Clin Hypertens (Greenwich) ; 20(2): 266-272, 2018 02.
Article de Anglais | MEDLINE | ID: mdl-29370469

RÉSUMÉ

We aimed to evaluate the association of aortic and brachial short-term blood pressure variability (BPV) with the presence of target organ damage (TOD) in hypertensive patients. One-hundred seventy-eight patients, aged 57 ± 12 years, 33% women were studied. TOD was defined by the presence of left ventricular hypertrophy on echocardiogram, microalbuminuria, reduced glomerular filtration rate, or increased aortic pulse wave velocity. Aortic and brachial BPV was assessed by 24-hour ambulatory BP monitoring (Mobil-O-Graph). TOD was present in 92 patients (51.7%). Compared to those without evidence of TOD, they had increased night-to-day ratios of systolic and diastolic BP (both aortic and brachial) and heart rate. They also had significant increased systolic BPV, as measured by both aortic and brachial daytime and 24-hours standard deviations and coefficients of variation, as well as for average real variability. Circadian patterns and short-term variability measures were very similar for aortic and brachial BP. We conclude that BPV is increased in hypertensive-related TOD. Aortic BPV does not add relevant information in comparison to brachial BPV.


Sujet(s)
Pression artérielle/physiologie , Surveillance ambulatoire de la pression artérielle/méthodes , Artère brachiale/physiopathologie , Hypertension artérielle , Sujet âgé , Analyse de variance , Rythme circadien , Corrélation de données , Échocardiographie/méthodes , Femelle , Débit de filtration glomérulaire , Rythme cardiaque , Humains , Hypertension artérielle/complications , Hypertension artérielle/diagnostic , Hypertension artérielle/physiopathologie , Mâle , Adulte d'âge moyen , Analyse de l'onde de pouls/méthodes , Espagne
6.
Kidney Blood Press Res ; 42(6): 1068-1077, 2017.
Article de Anglais | MEDLINE | ID: mdl-29197874

RÉSUMÉ

BACKGROUND/AIMS: Central blood pressure (BP) has been suggested to be a better estimator of hypertension-associated risks. We aimed to evaluate the association of 24-hour central BP, in comparison with 24-hour peripheral BP, with the presence of renal organ damage in hypertensive patients. METHODS: Brachial and central (calculated by an oscillometric system through brachial pulse wave analysis) office BP and ambulatory BP monitoring (ABPM) data and aortic pulse wave velocity (PWV) were measured in 208 hypertensive patients. Renal organ damage was evaluated by means of the albumin to creatinine ratio and the estimated glomerular filtration rate. RESULTS: Fifty-four patients (25.9%) were affected by renal organ damage, displaying either microalbuminuria (urinary albumin excretion ≥30 mg/g creatinine) or an estimated glomerular filtration rate (eGFR) <60 ml/min/1.73 m2. Compared to those without renal abnormalities, hypertensive patients with kidney damage had higher values of office brachial systolic BP (SBP) and pulse pressure (PP), and 24-h, daytime, and nighttime central and brachial SBP and PP. They also had a blunted nocturnal decrease in both central and brachial BP, and higher values of aortic PWV. After adjustment for age, gender, and antihypertensive treatment, only ABPM-derived BP estimates (both central and brachial) showed significant associations with the presence of renal damage. Odds ratios for central BP estimates were not significantly higher than those obtained for brachial BP. CONCLUSION: Compared with peripheral ABPM, cuff-based oscillometric central ABPM does not show a closer association with presence of renal organ damage in hypertensive patients. More studies, however, need to be done to better identify the role of central BP in clinical practice.


Sujet(s)
Mesure de la pression artérielle/effets indésirables , Hypertension artérielle/physiopathologie , Rein/traumatismes , Analyse de l'onde de pouls , Sujet âgé , Albuminurie/étiologie , Index de pression systolique cheville-bras , Aorte/physiopathologie , Pression artérielle , Mesure de la pression artérielle/méthodes , Surveillance ambulatoire de la pression artérielle/effets indésirables , Surveillance ambulatoire de la pression artérielle/méthodes , Femelle , Débit de filtration glomérulaire , Humains , Hypertension artérielle/complications , Mâle , Adulte d'âge moyen
7.
J Hypertens ; 35(11): 2324-2325, 2017 11.
Article de Anglais | MEDLINE | ID: mdl-28953592
8.
J Hypertens ; 35(10): 2000-2005, 2017 10.
Article de Anglais | MEDLINE | ID: mdl-28594710

RÉSUMÉ

BACKGROUND AND AIM: Central blood pressure (BP) is increasingly considered as a better estimator of hypertension associated risks. We aimed to evaluate the association of 24-h central BP, in comparison with 24-h peripheral BP, with the presence of target organ damage (TOD). METHODS: Cross-sectional study of 208 hypertensive patients, aged 57 ±â€Š12 years, 34% women. Office (mean of 4 measurements) and 24-h central and peripheral BP were measured by the oscillometric Mobil-O-Graph device. TOD was assessed at cardiac (left ventricular hypertrophy by echocardiography), renal (reduction of glomerular filtration rate and/or microalbuminuria), and arterial (increased aortic pulse wave velocity) levels. RESULTS: A total of 107 patients (51.4%) had TOD (77, 35% patients left ventricular hypertrophy; 54, 25.9% renal abnormalities; and 40, 19.2% arterial stiffness). All SBP and pulse BP estimates (office, 24-h, daytime, and night-time) were associated with the presence of TOD, after adjustment for age, sex, and antihypertensive treatment, with higher odds ratios for ambulatory-derived values. Odds ratios for central and peripheral BP were similar for all office, 24-h, daytime, and night-time BP. After simultaneous adjustment, peripheral, but not central, 24-h and night-time SBP and pulse pressures were associated with the presence of TOD. CONCLUSION: TOD in hypertension is associated with BP elevation, independently of the type of measurement (office or ambulatory, central or peripheral). Central BP, even monitored during 24 h, is not better associated with TOD than peripheral BP. These results do not support a routine measurement of 24-h central BP.


Sujet(s)
Mesure de la pression artérielle/méthodes , Mesure de la pression artérielle/statistiques et données numériques , Pression sanguine/physiologie , Hypertension artérielle , Adulte , Sujet âgé , Études transversales , Femelle , Humains , Hypertension artérielle/complications , Hypertension artérielle/diagnostic , Hypertension artérielle/épidémiologie , Hypertension artérielle/physiopathologie , Maladies du rein/complications , Maladies du rein/épidémiologie , Maladies du rein/physiopathologie , Mâle , Adulte d'âge moyen , Rigidité vasculaire/physiologie
9.
PLoS One ; 12(3): e0174583, 2017.
Article de Anglais | MEDLINE | ID: mdl-28346513

RÉSUMÉ

BACKGROUND/AIMS: Height-adjusted total kidney volume (htTKV) is the best marker of disease progression in early autosomal dominant polycystic kidney disease (ADPKD) when renal function still remains normal. The usefulness of cystatin-C as a biomarker to assess renal function according to renal volume has not been studied in ADPKD patients. METHODS: Observational and cross-sectional study of 62 ADPKD patients. htTKV, creatinine and cystatin-C estimated glomerular filtration rate (eGFR) were determined. Correlations between htTKV and eGFR were studied. A control group was used to determine the association between renal function differences and htTKV. RESULTS: htTKV significantly correlated with cystatin-C-eGFR (r = -0.384, p = 0.002) but not with creatinine-eGFR (r = -0.225, p = 0.078). With htTKV stratified into tertiles, a significant difference of cystatin-C-eGFR but not in creatinine-eGFR was detected in the third tertile when compared with the first tertile group (110.0±22.2 vs 121.3±7.2; p = 0.023 and 101.8±17.2 vs 106.9±15.1; p = 0.327 respectively). When cystatin-C-eGFR of the controls was used as the reference, htTKV above 605 ml/m identified with a 75% sensitivity and 84.9% specificity those patients with a significant worse kidney function. However, this cut-off value could not be identified using creatinine-eGFR. CONCLUSIONS: Cystatin-C-eGFR but not creatinine-eGFR correlated with htTKV in ADPKD patients in early stages of the disease. Differences in cystatin-C-eGFR but not in creatinine-eGFR have been identified through htTKV tertiles. A htTKV above 605 ml/m is associated with a worse renal function only if cystatin-C-eGFR is used. Cystatin-C-eGFR should be studied in prospective studies of early stages of ADPKD to determine its usefulness as an early marker of disease progression.


Sujet(s)
Cystatine C/sang , Débit de filtration glomérulaire/physiologie , Rein/physiopathologie , Polykystose rénale autosomique dominante/sang , Polykystose rénale autosomique dominante/physiopathologie , Adulte , Marqueurs biologiques/sang , Créatinine/sang , Évolution de la maladie , Femelle , Humains , Rein/imagerie diagnostique , Mâle , Taille d'organe/physiologie , Polykystose rénale autosomique dominante/imagerie diagnostique , Études prospectives , Échographie
10.
Medicine (Baltimore) ; 95(49): e5595, 2016 Dec.
Article de Anglais | MEDLINE | ID: mdl-27930582

RÉSUMÉ

Cardiovascular disease, closely related to an early appearance of hypertension, is the most common mortality cause among autosomal dominant polycystic kidney disease patients (ADPKD). The development of hypertension is related to an increase in renal volume. Whether the increasing in the renal volume before the onset of hypertension leads to a major cardiovascular risk in ADPKD patients remains unknown.Observational and cross-sectional study of 62 normotensive ADPKD patients with normal renal function and a group of 28 healthy controls. Renal volume, blood pressure, and renal (urinary albumin excretion), blood vessels (carotid intima media thickness and carotid-femoral pulse wave velocity), and cardiac (left ventricular mass index and diastolic dysfunction parameters) asymptomatic organ damage were determined and were considered as continuous variables. Correlations between renal volume and the other parameters were studied in the ADPKD population, and results were compared with the control group. Blood pressure values and asymptomatic organ damage were used to assess the cardiovascular risk according to renal volume tertiles.Even though in the normotensive range, ADPKD patients show higher blood pressure and major asymptomatic organ damage than healthy controls. Asymptomatic organ damage is not only related to blood pressure level but also to renal volume. Multivariate regression analysis shows that microalbuminuria is only associated with height adjusted renal volume (htTKV). An htTKV above 480 mL/m represents a 10 times higher prevalence of microalbuminuria (4.8% vs 50%, P < 0.001). Normotensive ADPKD patients from the 2nd tertile renal volume group (htTKV > 336 mL/m) show higher urinary albumin excretion, but the 3rd tertile htTKV (htTKV > 469 mL/m) group shows the worst cardiovascular risk profile.Normotensive ADPKD patients show in the early stages of the disease with slight increase in renal volume, higher cardiovascular risk than healthy controls. An htTKV above 468 mL/m is associated with the greatest increase in cardiovascular risk of normotensive ADPKD patients with normal renal function. Early strategies to slow the progression of the cardiovascular risk of these patients might be beneficial in their long-term cardiovascular survival.


Sujet(s)
Maladies cardiovasculaires/étiologie , Maladies cardiovasculaires/physiopathologie , Hypertension artérielle/étiologie , Rein/anatomopathologie , Polykystose rénale autosomique dominante/complications , Adulte , Facteurs âges , Analyse de variance , Pression sanguine/physiologie , Études transversales , Évolution de la maladie , Femelle , Humains , Hypertension artérielle/physiopathologie , Mâle , Adulte d'âge moyen , Analyse multifactorielle , Taille d'organe , Polykystose rénale autosomique dominante/diagnostic , Pronostic , Courbe ROC , Valeurs de référence , Appréciation des risques , Indice de gravité de la maladie , Facteurs sexuels , Statistique non paramétrique
11.
Am J Nephrol ; 39(6): 528-35, 2014.
Article de Anglais | MEDLINE | ID: mdl-24942911

RÉSUMÉ

BACKGROUND/AIMS: Cyclosporine (CsA) is a calcineurin inhibitor widely used as an immunosuppressant in organ transplantation. Previous studies demonstrated the relationship between CsA and renal sodium transporters such as the Na-K-2Cl cotransporter in the loop of Henle (NKCC2). Experimental models of CsA-induced hypertension have shown an increase in renal NKCC2. METHODS: Using immunoblotting of urinary exosomes, we investigated in CsA-treated kidney transplant patients (n = 39) the excretion of NKCC2 and Na-Cl cotransporter (NCC) and its association with blood pressure (BP) level. We included 8 non-CsA-treated kidney transplant patients as a control group. Clinical data, immunosuppression and hypertension treatments, blood and 24-hour urine tests, and 24-hour ambulatory BP monitoring were recorded. RESULTS: CsA-treated patients tended to excrete a higher amount of NKCC2 than non-CsA-treated patients (mean ± SD, 175 ± 98 DU and 90 ± 70.3 DU, respectively; p = 0.05) and showed higher BP values (24-hour systolic BP 138 ± 17 mm Hg and 112 ± 12 mm Hg, p = 0.003; 24-hour diastolic BP, 83.8 ± 9.8 mm Hg and 72.4 ± 5.2 mm Hg, p = 0.015, respectively). Within the CsA-treated group, there was no correlation between either NKCC2 or NCC excretion and BP levels. This was confirmed by a further analysis including potential confounding factors. On the other hand, a significant positive correlation was observed between CsA blood levels and the excretion of NKCC2 and NCC. CONCLUSION: Overall, these results support the hypothesis that CsA induces an increase in NKCC2 and NCC in urinary exosomes of renal transplant patients. The fact that the increase in sodium transporters in urine did not correlate with the BP level suggests that in kidney transplant patients, other mechanisms could be implicated in CsA-induced hypertension.


Sujet(s)
Ciclosporine/usage thérapeutique , Exosomes/métabolisme , Rejet du greffon/prévention et contrôle , Immunosuppresseurs/usage thérapeutique , Transplantation rénale , Rein/métabolisme , Sodium/métabolisme , Membre-1 de la famille-12 des transporteurs de solutés/métabolisme , Adulte , Sujet âgé , Pression sanguine , Études cas-témoins , Ciclosporine/pharmacologie , Exosomes/effets des médicaments et des substances chimiques , Femelle , Humains , Immunosuppresseurs/pharmacologie , Rein/effets des médicaments et des substances chimiques , Mâle , Adulte d'âge moyen , Membre-1 de la famille-12 des transporteurs de solutés/effets des médicaments et des substances chimiques , Membre-3 de la famille-12 des transporteurs de solutés/effets des médicaments et des substances chimiques , Membre-3 de la famille-12 des transporteurs de solutés/métabolisme , Urine , Jeune adulte
13.
Clin Kidney J ; 6(5): 457-63, 2013 Oct.
Article de Anglais | MEDLINE | ID: mdl-26064509

RÉSUMÉ

Cardiovascular (CV) complications are the major cause of death in autosomal-dominant polycystic kidney disease (ADPKD) patients. Hypertension is common in these patients even before the onset of renal insufficiency. Blood pressure (BP) elevation is a key factor in patient outcome, mainly owing to the high prevalence of target organ damage together with a poor renal prognosis when BP is increased. Many factors have been implicated in the pathogenesis of hypertension, including the renin-angiotensin-aldosterone system (RAAS) stimulation. Polycystin deficiency may also contribute to hypertension because of its potential role in regulating the vascular tone. Early diagnosis and treatment of hypertension improve the CV and renal complications of this population. Ambulatory BP monitoring is recommended for prompt diagnosis of hypertension. CV risk assessment is mandatory. Even though a nonpharmacological approach should not be neglected, RAAS inhibitors are the cornerstone of hypertension treatment. Calcium channel blockers (CCBs) should be avoided unless resistant hypertension is present. The BP should be <140/90 mmHg in all ADPKD patients and a more intensive control (<135/85 mmHg) should be pursued as soon as microalbuminuria or left ventricle hypertrophy is present.

15.
Sci Transl Med ; 2(46): 46ps42, 2010 Aug 25.
Article de Anglais | MEDLINE | ID: mdl-20739680

RÉSUMÉ

Clinical proteomics has yielded some early positive results-the identification of potential disease biomarkers-indicating the promise for this analytical approach to improve the current state of the art in clinical practice. However, the inability to verify some candidate molecules in subsequent studies has led to skepticism among many clinicians and regulatory bodies, and it has become evident that commonly encountered shortcomings in fundamental aspects of experimental design mainly during biomarker discovery must be addressed in order to provide robust data. In this Perspective, we assert that successful studies generally use suitable statistical approaches for biomarker definition and confirm results in independent test sets; in addition, we describe a brief set of practical and feasible recommendations that we have developed for investigators to properly identify and qualify proteomic biomarkers, which could also be used as reporting requirements. Such recommendations should help put proteomic biomarker discovery on the solid ground needed for turning the old promise into a new reality.


Sujet(s)
Marqueurs biologiques , Protéomique , Humains , Spectrométrie de masse
16.
Kidney Int ; 77(8): 736-42, 2010 Apr.
Article de Anglais | MEDLINE | ID: mdl-20130532

RÉSUMÉ

Urinary exosomes have been proposed as starting material for discovery of protein biomarkers of kidney disease. Current protocols for their isolation use a two-step differential centrifugation process. Due to their low density, exosomes are expected to remain in the low-speed (17,000 x g) supernatant and to sediment only when the sample is spun at high speed (200,000 x g). Analysis using western blot and electron microscopy found that urinary exosomes are also present in the low-speed pellet entrapped by polymeric Tamm-Horsfall protein, thus diminishing the procedure's reproducibility. Here we show that addition of dithiothreitol to the low-speed pellet disrupted the polymeric network, presumably by reduction of disulfide bonds linking the monomers. This modification shifted the exosomal proteins from the low- to the high-speed pellet. Also, by shifting the Tamm-Horsfall protein to the high-speed pellet, the use of dithiothreitol makes it feasible to use Tamm-Horsfall protein to normalize excretion rates of exosomal proteins in spot urines. We tested this by western blot, and found that there was a high degree of correlation between exosomal proteins and Tamm-Horsfall protein in the high-speed pellet. Since the yield of exosomes by differential centrifugation can be increased by chemical reduction, Tamm-Horsfall protein may be a suitable normalizing variable for urinary exosome studies when quantitative urine collections are not practical.


Sujet(s)
Exosomes/ultrastructure , Mucoprotéines/isolement et purification , Mucoprotéines/ultrastructure , Voies urinaires/ultrastructure , Adulte , Marqueurs biologiques/urine , Technique de Western , Humains , Mâle , Microscopie électronique , Uromoduline
17.
Nephron Physiol ; 114(3): p25-34, 2010.
Article de Anglais | MEDLINE | ID: mdl-20068364

RÉSUMÉ

BACKGROUND: Altered renal sodium handling has a major pathogenic role in salt-sensitive hypertension. Renal sodium transporters are present in urinary exosomes. We hypothesized that sodium transporters would be excreted into the urine in different amounts in response to sodium intake in salt-sensitive versus salt-resistant patients. METHODS: Urinary exosomes were isolated by ultracentrifugation, and their content of Na-K-2Cl cotransporter (NKCC2) and Na-Cl cotransporter (NCC) was analyzed by immunoblotting. Animal studies: NKCC2 and NCC excretion was measured in 2 rat models to test whether changes in sodium transporter excretion are indicative of regulated changes in the kidney tissue. Human studies: in hypertensive patients (n = 41), we investigated: (1) a possible correlation between sodium reabsorption and urinary exosomal excretion of sodium transporters, and (2) the profile of sodium transporter excretion related to blood pressure (BP) changes with salt intake. A 24-hour ambulatory BP monitoring and a 24-hour urine collection were performed after 1 week on a low- and 1 week on a high-salt diet. RESULTS: Animal studies: urinary NKCC2 and NCC excretion rates correlated well with their abundance in the kidney. Human studies: 6 patients (15%) were classified as salt sensitive. The NKCC2 and NCC abundance did not decrease after the high-salt period, when the urinary sodium reabsorption decreased from 99.7 to 99.0%. In addition, the changes in BP with salt intake were not associated with a specific profile of exosomal excretion. CONCLUSIONS: Our results do not support the idea that excretion levels of NKCC2 and NCC via urinary exosomes are markers of tubular sodium reabsorption in hypertensive patients.


Sujet(s)
Exosomes , Hypertension artérielle/métabolisme , Tubules rénaux/métabolisme , Symporteurs des ions sodium-chlorure/urine , Sodium/métabolisme , Membre-1 de la famille-12 des transporteurs de solutés/urine , Animaux , Pression sanguine , Femelle , Humains , Hypertension artérielle/urine , Rein/métabolisme , Mâle , Rats , Sodium/urine , Symporteurs des ions sodium-chlorure/métabolisme , Sodium alimentaire/administration et posologie , Membre-1 de la famille-12 des transporteurs de solutés/métabolisme
18.
Kidney Int ; 76(12): 1268-76, 2009 Dec.
Article de Anglais | MEDLINE | ID: mdl-19812541

RÉSUMÉ

Mutations in the NPHS1 gene cause congenital nephrotic syndrome of the Finnish type presenting before the first 3 months of life. Recently, NPHS1 mutations have also been identified in childhood-onset steroid-resistant nephrotic syndrome and milder courses of disease, but their role in adults with focal segmental glomerulosclerosis remains unknown. Here we developed an in silico scoring matrix to evaluate the pathogenicity of amino-acid substitutions using the biophysical and biochemical difference between wild-type and mutant amino acid, the evolutionary conservation of the amino-acid residue in orthologs, and defined domains, with the addition of contextual information. Mutation analysis was performed in 97 patients from 89 unrelated families, of which 52 presented with steroid-resistant nephrotic syndrome after 18 years of age. Compound heterozygous or homozygous NPHS1 mutations were identified in five familial and seven sporadic cases, including one patient 27 years old at onset of the disease. Substitutions were classified as 'severe' or 'mild' using this in silico approach. Our results suggest an earlier onset of the disease in patients with two 'severe' mutations compared to patients with at least one 'mild' mutation. The finding of mutations in a patient with adult-onset focal segmental glomerulosclerosis indicates that NPHS1 analysis could be considered in patients with later onset of the disease.


Sujet(s)
Glomérulonéphrite segmentaire et focale/génétique , Protéines membranaires/génétique , Mutation , Adulte , Âge de début , Substitution d'acide aminé , Enfant , Enfant d'âge préscolaire , Études de cohortes , Femelle , Études d'associations génétiques , Glomérulonéphrite segmentaire et focale/congénital , Hétérozygote , Homozygote , Humains , Nourrisson , Nouveau-né , Mâle , Protéines membranaires/composition chimique , Mutation faux-sens , Syndrome néphrotique/congénital , Syndrome néphrotique/génétique , Espagne
19.
Nephrol Dial Transplant ; 24(10): 3089-96, 2009 Oct.
Article de Anglais | MEDLINE | ID: mdl-19458060

RÉSUMÉ

BACKGROUND: Mutations in the TRPC6 gene have been reported in six families with adult-onset (17-57 years) autosomal dominant focal segmental glomerulosclerosis (FSGS). Electrophysiology studies confirmed augmented calcium influx only in three of these six TRPC6 mutations. To date, the role of TRPC6 in childhood and adulthood non-familial forms is unknown. METHODS: TRPC6 mutation analysis was performed by direct sequencing in 130 Spanish patients from 115 unrelated families with FSGS. An in silico scoring matrix was developed to evaluate the pathogenicity of amino acid substitutions, by using the bio-physical and bio-chemical differences between wild-type and mutant amino acid, the evolutionary conservation of the amino acid residue in orthologues, homologues and defined domains, with the addition of contextual information. RESULTS: Three new missense substitutions were identified in two clinically non-familial cases and in one familial case. The analysis by means of this scoring system allowed us to classify these variants as likely pathogenic mutations. One of them was detected in a female patient with unusual clinical features: mesangial proliferative FSGS in childhood (7 years) and partial response to immunosupressive therapy (CsA + MMF). Asymptomatic carriers of this likely mutation were found within her family. CONCLUSIONS: We describe for the first time TRPC6 mutations in children and adults with non-familial FSGS. It seems that TRPC6 is a gene with a very variable penetrance that may contribute to glomerular diseases in a multi-hit setting.


Sujet(s)
Glomérulonéphrite segmentaire et focale/génétique , Canaux cationiques TRPC/génétique , Adolescent , Adulte , Enfant , Enfant d'âge préscolaire , Analyse de mutations d'ADN , Femelle , Humains , Nourrisson , Adulte d'âge moyen , Membre-6 de la sous-famille C de canaux cationiques à potentiel de récepteur transitoire , Jeune adulte
20.
Clin J Am Soc Nephrol ; 3(3): 790-3, 2008 May.
Article de Anglais | MEDLINE | ID: mdl-18322042

RÉSUMÉ

BACKGROUND AND OBJECTIVES: Autosomal dominant polycystic kidney disease is a systemic disorder with a wide range of extrarenal involvement. The scope of this study was to analyze the prevalence of seminal cysts and to correlate these findings with the sperm parameters in patients with autosomal dominant polycystic kidney disease. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: A prospective study enrolled 30 adult men with autosomal dominant polycystic kidney disease. Of these 30 patients, 22 agreed to provide a semen sample for analysis, and 28 of 30 agreed to undergo an ultrasound rectal examination. Data obtained from the semen tests and from the ultrasound study were compared. RESULTS: Cysts in the seminal tract were present in 10 (43.47%) of 28 individuals. Twenty of 22 patients showed abnormal semen parameters, with asthenozoospermia as the most common finding. No correlation between ultrasound findings and sperm abnormalities was observed. CONCLUSIONS: The presence of cysts in the seminal tract is remarkably high (43.47%); however, this finding does not correlate with sperm abnormalities, which are also a frequent finding, especially asthenozoospermia. This semen abnormality is probably related to the abnormal function of polycystins. More attention should be paid to reproductive aspects in the initial evaluation of patients with autosomal dominant polycystic kidney disease before their ability to conceive is further impaired by uremia.


Sujet(s)
Kystes/étiologie , Maladies de l'appareil génital mâle/étiologie , Système génital de l'homme/anatomopathologie , Infertilité masculine/étiologie , Polykystose rénale autosomique dominante/complications , Sperme/cytologie , Spermatozoïdes/anatomopathologie , Adulte , Asthénozoospermie/étiologie , Asthénozoospermie/anatomopathologie , Kystes/complications , Kystes/imagerie diagnostique , Kystes/épidémiologie , Kystes/anatomopathologie , Maladies de l'appareil génital mâle/complications , Maladies de l'appareil génital mâle/imagerie diagnostique , Maladies de l'appareil génital mâle/épidémiologie , Maladies de l'appareil génital mâle/anatomopathologie , Système génital de l'homme/imagerie diagnostique , Humains , Infertilité masculine/imagerie diagnostique , Infertilité masculine/épidémiologie , Infertilité masculine/anatomopathologie , Mâle , Polykystose rénale autosomique dominante/imagerie diagnostique , Polykystose rénale autosomique dominante/épidémiologie , Polykystose rénale autosomique dominante/anatomopathologie , Prévalence , Études prospectives , Prostate/anatomopathologie , Facteurs de risque , Vésicules séminales/anatomopathologie , Spermatocèle/complications , Spermatocèle/anatomopathologie , Testicule/anatomopathologie , Échographie
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