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1.
Int J Legal Med ; 138(3): 873-882, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38177496

RESUMEN

Artificial intelligence (AI) is increasingly used in forensic anthropology and genetics to identify the victim and the cause of death. The large autopsy samples from persons with traumatic causes of death but without comorbidities also offer possibilities to analyze normal histology with AI. We propose a new deep learning-based method to rapidly count glomerular number and measure glomerular density (GD) and volume in post-mortem kidney samples obtained in a forensic population. We assessed whether this new method detects glomerular differences between men and women without known kidney disease. Autopsies performed between 2009 and 2015 were analyzed if subjects were aged ≥ 18 years and had no known kidney disease, diabetes mellitus, or hypertension. A large biopsy was taken from each kidney, stained with hematoxylin and eosin, and scanned. An in-house developed deep learning-based algorithm counted the glomerular density (GD), number, and size. Out of 1165 forensic autopsies, 86 met all inclusion criteria (54 men). Mean (± SD) age was 43.5 ± 14.6; 786 ± 277 glomeruli were analyzed per individual. There was no significant difference in GD between men and women (2.18 ± 0.49 vs. 2.30 ± 0.57 glomeruli/mm2, p = 0.71); glomerular diameter, area, and volume also did not differ. GD correlated inversely with age, kidney weight, and glomerular area. Glomerular area and volume increased significantly with age. In this study, there were no sex differences in glomerular density or size. Considering the size of the kidney samples, the use of the presented deep learning method can help to analyze large renal autopsy biopsies and opens perspectives for the histological study of other organs.


Asunto(s)
Aprendizaje Profundo , Enfermedades Renales , Femenino , Humanos , Masculino , Caracteres Sexuales , Inteligencia Artificial , Riñón , Autopsia
2.
Nephrol Dial Transplant ; 39(2): 242-250, 2024 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-37553142

RESUMEN

BACKGROUND: Microvascular structural alteration and dysfunction is a hallmark of arterial hypertension. So far, the visualization and the quantification of renal microcirculation in humans has been hampered by the lack of non-nephrotoxic and non-invasive radiologic techniques. Contrast-enhanced ultrasonography (CEUS) is an appealing method to investigate renal microcirculation and has not been investigated in this setting. We aimed to compare renal microcirculation in normotensive (NT) and hypertensive (HT) participants using CEUS at rest and during a sympathetic stress test. METHODS: We measured the renal perfusion index (PI, primary outcome), the renal resistive index (RRI), beat-to-beat systemic hemodynamics and plasma catecholamines before and during a 2-min cold pressor test (CPT) in NT and HT participants. Linear mixed model analysis was used to compare the effect of the CPT on the variables of interest. RESULTS: Seventy-three participants (32 HT) with normal kidney function were included. HT participants had a lower baseline PI compared with NT participants [median (interquartile range) 1476 (959-2155) arbitrary units (a.u.) vs 2062 (1438-3318) a.u., P < .001]. The CPT increased blood pressure, heart rate and catecholamines in all participants. The increase in PI observed in NT during the CPT was blunted in HT [+504 (117-920) a.u. vs +1159 (678-2352) a.u in NT, interaction P = .013]. Age, sex and body mass index did not modify these results. CONCLUSIONS: HT patients had a lower basal renal cortical perfusion. During the cold pressor test, HT participants had a smaller increase in the PI, suggesting that renal cortical flow reserve is impaired.


Asunto(s)
Hipertensión , Riñón , Humanos , Ultrasonografía , Catecolaminas , Perfusión
3.
J Clin Med ; 12(12)2023 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-37373834

RESUMEN

(1) Background: The renal microcirculation is essential to maintain the renal function, but its determinants in humans have been poorly studied. Contrast-enhanced ultrasound (CEUS) allows the non-invasive quantification of the cortical micro-perfusion at the bedside using the perfusion index (PI). The aims of this study were to assess whether differences exist in PI between healthy males and females and to identify clinical determinants associated with cortical micro-perfusion. (2) Methods: Healthy, normotensive volunteers (eGFR > 60 mL/min/1.73 m2, no albuminuria) underwent CEUS under standardized conditions with the destruction-reperfusion (DR) technique. The mean PI of four DR sequences was reported as the primary outcome measure (3) Results: A total of 115 subjects (77 females and 38 males) completed the study; the mean ± SD age was, respectively, 37.1 ± 12.2 and 37.1 ± 12.7 years in females and males, and the mean eGFR was 105.9 ± 15.1 and 91.0 ± 17.4 mL/min/1.73 m2. The PI (median) was higher in females than in males, i.e., 2705 (IQR 1641-3777) vs. 1965 (IQR 1294-3346) arbitrary units (a.u), p = 0.02). A correlation analysis showed positive associations between PI and eGFR, female sex, heart rate, plasma renin activity (PRA) and plasma aldosterone concentrations (PAC), negative associations with potassium, bicarbonate and systolic blood pressure, and no associations with age, body mass index and renal resistive index (RRI). In a multivariate linear regression analysis, only PRA remained significantly associated with PI. (4) Conclusions: Although the PI was higher among females, this association was no longer significant after adjustment for covariates. There was no difference in females tested during the follicular or the luteal phases. In conclusion, the PI was only weakly influenced by classic clinical variables, but was positively associated with PRA, suggesting that the renin-angiotensin system plays a role in the regulation of the cortical micro-perfusion in humans. Identifying which other factors contribute to the large variations in micro-perfusion across individuals needs further study.

4.
Kidney Blood Press Res ; 47(11): 664-673, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36191559

RESUMEN

INTRODUCTION: The measurement of renal functional reserve (RFR) can unmask glomerular hyperfiltration in residual nephrons, but its determination is time-consuming. In this study, we assessed whether contrast-enhanced ultrasound (CEUS) is a valuable alternative to the gold standard inulin clearance and whether L-arginine or protein shakes lead to similar changes in glomerular filtration rate (GFR) as animal proteins in men and women. METHODS: Changes in GFR and renal microperfusion were studied in 25 healthy subjects (8 men, 17 women) by simultaneously performing inulin clearance and CEUS (perfusion index, PI) before and 1 and 2 h after different protein loads (L-arginine, protein shake or meat). The Doppler parameters - renal resistive index (RRI) and pulsatility index (PuI) - were also measured. RESULTS: None of the oral protein loads induced significant changes in CEUS-assessed PI. Only meat increased inulin clearance (from 111.2 ± 16.0 to 149.8 ± 27.2 mL/min, p < 0.05) and mobilized RFR, while L-arginine decreased GFR (106.7 ± 45.3 to 86.3 ± 42.6 mL/min, p < 0.05). Protein shakes had a neutral effect. There were no correlations between changes in inulin clearance and PI. At Doppler, RRI and PuI increased after meat intake (from 0.647 ± 0.029 to 0.694 ± 0.050 a.u., p < 0.05 and from 1.130 ± 0.087 to 1.318 ± 0.163 a.u., p < 0.05, respectively), but their changes also did not correlate with changes in inulin clearance. Results were similar in both sexes. CONCLUSIONS: CEUS is not a valuable alternative for inulin clearance to measure RFR. Meat ingestion leads to modest changes in renal Doppler parameters and to glomerular hyperfiltration in both women and men, while protein shakes and L-arginine do not.


Asunto(s)
Inulina , Enfermedades Renales , Masculino , Animales , Humanos , Femenino , Pruebas de Función Renal , Tasa de Filtración Glomerular , Carne , Arginina
5.
Front Cardiovasc Med ; 9: 899327, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35669471

RESUMEN

Background: Renal microcirculation is essential for regulation of the glomerular filtration rate, the reabsorption of salt and water from the interstitium, and hence the blood pressure. Renal ultrasonography coupled to Doppler analysis and contrast-enhanced ultrasound enables the study of renal perfusion. So far, physiologic interventions have rarely been performed to assess the renal perfusion. The objective of our study was to measure the renal perfusion in response to a cold pressor test (CPT). Methods: Healthy adult participants were exposed to a 2 min CPT or a sham exposure (body temperature). Systemic hemodynamics, renal resistive index (RRI) and renal perfusion index (PI) were measured before and during the CPT or the sham exposure. Renal responses were compared using a paired Student's t-test or Wilcoxon signed rank test. Pearson correlation test was used to test association of variables of interest. Results: Forty-one normotensive participants (21 women) were included in the study. Mean blood pressure and heart rate both increased with the CPT. The RRI decreased from 0.60 ± 0.05 arbitrary units (AU) to 0.58 ± 0.05 AU (p < 0.05) and the PI increased from 2,074 AU (1,358-3,346) to 3,800 AU (2,118-6,399) (p < 0.05) (+66% (24-106%)). Compared to the sham exposure, the increase in PI with the CPT was more marked. There was a negative association between the increase in heart rate and mean blood pressure with the RRI (r: -0.550, p = 0.002 and r: -0.395, P = 0.016), respectively. Conclusion: Doppler Ultrasound and CEUS enable the detection of physiological changes within the macro- and microvascular renal circulation. The CPT decreases the RRI and increases the PI. Whether these changes are present in pathological states such as diabetes or hypertension will need additional studies.

6.
Nephrol Dial Transplant ; 37(4): 705-712, 2022 03 25.
Artículo en Inglés | MEDLINE | ID: mdl-33426563

RESUMEN

BACKGROUND: Disturbances in renal microcirculation play an important role in the pathophysiology of chronic kidney disease (CKD), but the lack of easy accessible techniques hampers our understanding of the regulation of the renal microcirculation in humans. We assessed whether contrast-enhanced ultrasound (CEUS) can identify differences in cortical perfusion and alterations induced by different dietary salt intakes in CKD patients and controls. METHODS: Participants underwent CEUS twice: once after 5 days of high-salt (HS) intake, and again after 5 days of low salt (LS) diet. Sonovue® (0.015 mL/kg/min) was perfused as contrast agent and four consecutive destruction-reperfusion sequences were analysed per visit. The primary outcome measure was the (change in) mean perfusion index (PI) of the renal cortex. RESULTS: Forty healthy volunteers (mean age ± standard deviation 50 ± 8 years) and 18 CKD Stages 2-4 patients [aged 55 ± 11 years, estimated glomerular filtration rate (eGFR) 54 ± 28 mL/min/1.73 m2] were included and underwent CEUS without side effects. Under HS conditions, cortical PI was significantly lower in CKD patients [1618 ± 1352 versus 3176 ± 2278 arbitrary units (a.u) in controls, P = 0.034]. Under LS, renal PI increased in CKD patients (with +1098 to 2716 ± 1540 a.u., P = 0.048), whereas PI remained stable in controls. In the continuous analysis, PI correlated with eGFR (Spearman's r = 0.54, P = 0.005) but not with age, sex, blood pressure or aldosterone levels. CONCLUSIONS: CEUS identified important reductions in cortical micro-perfusion in patients with moderate CKD. Lowering salt intake increased perfusion in CKD patients, but not in controls, underlining the benefits of an LS diet in CKD patients. Whether a low PI is an early sign of kidney damage and predicts renal function decline needs further study.


Asunto(s)
Insuficiencia Renal Crónica , Cloruro de Sodio Dietético , Femenino , Tasa de Filtración Glomerular , Voluntarios Sanos , Humanos , Riñón/diagnóstico por imagen , Masculino , Perfusión , Insuficiencia Renal Crónica/diagnóstico por imagen , Cloruro de Sodio Dietético/efectos adversos , Ultrasonografía/métodos
7.
Int J Paediatr Dent ; 31(4): 504-519, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33289182

RESUMEN

BACKGROUND: Malignant neoplasms that affect children and adolescents are predominantly embryonic and generally affect blood system cells and supporting tissues. AIM: This study aimed to summarize the scientific evidence about the prevalence of malignant lesions in the oral cavity of children and adolescents. DESIGN: In this systematic review and meta-analysis (PROSPERO CRD42020158338), data were obtained from seven databases and the gray literature. Cross-sectional observational studies on the prevalence of biopsied oral pediatric malignancies were included. The Newcastle-Ottawa Scale assessed the quality of the included studies, and the GRADE approach evaluated the evidence certainty. The meta-analysis prevalence was calculated using MedCalc® software, adopting a 95% confidence level (CI; random-effect model). RESULTS: Forty-two studies were included in the meta-analysis. Of the 64,522 biopsies, the prevalence of malignant lesions was 1.93% (n = 1,100; 95% CI = 1.21%-2.80%). Countries with a low socioeconomic profile showed the highest prevalence. The sample size did not influence the prevalence of oral malignancies, and unspecified lymphomas (12.08%; 95% CI = 5.73%-20.37%) and rhabdomyosarcoma (10.53%; 95% CI = 7.28%-14.30%) were the most common lesions. CONCLUSIONS: Oral malignant lesions biopsied in children and adolescents had a prevalence of <3%, and lymphomas and sarcomas were the most prevalent lesions.


Asunto(s)
Boca , Neoplasias , Adolescente , Niño , Estudios Transversales , Humanos , Prevalencia
8.
J Hypertens ; 38(1): 159-166, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31503134

RESUMEN

OBJECTIVE: There is increasing evidence that sodium can be stored in the skin and muscles without being osmotically active, yet whether acute changes in dietary sodium intake alter sweat and muscle sodium content has not been investigated previously. METHODS: In a cross-over design, we assessed muscle sodium content by Na-MRI in 38 healthy normotensive volunteers (aged 33.5 ±â€Š11.1 years, 76.3% women) after 5 days of high-sodium diet (6 g of salt added to their normal diet) and 5 days of a low-sodium diet. In a subgroup of 18 participants (72.2% women) we conducted quantitative pilocarpine iontophoretic sweat collections and measured the sodium concentration in sweat. Plasma aldosterone and plasma renin activity levels were measured in all participants. RESULTS: Under high-sodium diet conditions urinary sodium excretion, muscle sodium content and sweat sodium concentration all increased significantly. Muscle sodium content (rm = 0.47, P = 0.03) and sodium sweat concentration (rm = 0.72, P < 0.001) correlated positively with salt intake as estimated by 24-h urine sodium excretion. Age, sex or the phase of the menstrual cycle did not influence muscle or sweat sodium concentrations or their changes. In contrast, plasma aldosterone levels were negatively associated with both muscle sodium (rs = -0.42, P = 0.0001) and sweat sodium content (rs = -0.52, P = 0.002). Plasma renin activity correlated negatively with sweat sodium (rs = -0.43, P = 0.012) and muscle sodium levels (rs = -0.42, P < 0.001). CONCLUSION: Muscle and sweat sodium concentrations are significantly higher on a high-salt intake in healthy male and female individuals, suggesting that muscle and sweat play a role in regulating sodium balance in humans.


Asunto(s)
Músculo Esquelético/química , Sodio en la Dieta/análisis , Sudor/química , Adulto , Aldosterona/sangre , Presión Sanguínea/fisiología , Estudios Cruzados , Femenino , Humanos , Masculino , Persona de Mediana Edad , Músculo Esquelético/metabolismo , Sodio en la Dieta/metabolismo , Sudor/metabolismo , Adulto Joven
9.
Z Naturforsch C J Biosci ; 57(9-10): 773-6, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12440709

RESUMEN

The rare lupene derivative named resinone has only been isolated before from Fluorensia resinosa. We now report the isolation of this compound from the bark of the new recently described Acacia cedilloi (Fabaceae), and the revision of its structure to 16beta-hydroxylup-20(29)-en-3-one, based on NMR and MS spectral data. The detailed 1H and 13C NMR assignments of resinone and its acetate achieved by 1D and 2D NMR experiments (including DEPT, COSY, HMQC and HMBC) are reported. In addition, the study of A. cedilloi and A. gaumeri afforded the known related lupenes lupeol and lupenone, the acyclic squalene, the sterols beta-sitosterol, stigmasta-7,22-dien-3beta-ol (spinasterol) and stigmasta-5,22,25-trien-3beta-ol (22-dehydroclerosterol) as well as alpha-tocopherol and beta-carotene.


Asunto(s)
Acacia/química , Triterpenos/química , Espectroscopía de Resonancia Magnética/métodos , Modelos Moleculares , Conformación Molecular , Especificidad de la Especie , Triterpenos/aislamiento & purificación
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