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Naturally Occurring Asbestos (NOA) has drawn the attention worldwide when investigation revealed an increased incidence of malignant mesothelioma in population living near NOA sites. In Basilicata region (South Italy), population living in the villages of Castelluccio Superiore and Inferiore, Lauria, Latronico, Episcopia, San Severino Lucano, and Francavilla in Sinni may be considered at high risk of asbestos exposure because these villages are either surrounded by or built on NOA-rich ophiolitic outcrops. In this work we investigated an asbestos tremolite sample coming from the ophiolitic rocks outcropping in the quarry of Iacolinei, widely used in the past to extract aggregates for various applications. A detailed mineralogical characterization has been attained by using a multi-analytical approach (EMPA, SEM-EDS, TEM-EDS, Mössbauer, µ-Raman, X-ray powder diffraction, and thermal analysis). Morphological investigation highlighted that the sample is composed of long fibers (> 5 µm) with a significant fraction (ca. 55%) having width below 0.25 µm, considered the most biologically active fibers. Moreover, the crystal chemical characterization showed that Fe occurs at the octahedral sites of the tremolite structure. It should be noted that Fe plays a primary role in the toxicity of asbestos. Based on these results, the investigated asbestos tremolite may be considered a potent mesothelial carcinogen, requiring therefore special attention for public health protection purposes. Investigations using sentinel animals to assess the diffusion of the tremolite fibers into the environment from the serpentinite rocks and soils of Iacolinei quarry are in progress.
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Asbestos Anfíboles , Italia , Asbestos Anfíboles/análisis , Difracción de Rayos X , Sedimentos Geológicos/química , Monitoreo del AmbienteRESUMEN
Background: Conventional glucocorticoids (C-GC) replacement regimens have a detrimental effect on skeletal health in patients with adrenal insufficiency (AI), ultimately leading to an increased fracture risk. The novel dual-release hydrocortisone (DR-HC) formulations are characterized by a more favourable safety profile on various clinical endpoints. Data comparing the impact of C-GC and DR-HC on bone, however, are scarce. Methods: Twenty-seven patients with autoimmune primary AI (PAI; 13 treated with C-GC and 14 treated with DR-HC) were evaluated to compare bone-related parameters between the two treatment groups. Results: No significant differences between the two treatments groups were observed with respect to bone turnover markers. Patients treated with C-GC showed a lower bone mineral density (BMD) at lumbar spine (LS; 0.791 ± 0.195 vs. 0.942 ± 0.124 g/cm2, p=0.025) and at femoral neck (FN; 0.633 ± 0.114 vs. 0.716 ± 0.088 g/cm2, p=0.045). Moreover, they were characterized by a lower trabecular bone score (TBS; 1.236 ± 0.035 vs. 1.383 ± 0.030, p=0.004) and by a higher mean number of vertebral fractures per patient (0.75 vs. 0 fractures, p=0.002). TBS was the best predictor of fracture risk, with a pseudo-R2 of 0.593; moreover, at mediation analysis, it was able to fully explain the observed detrimental effect of C-GC, compared to DR-HC, on fracture risk. Conclusions: These results suggest that DR-HC is associated with less bone-related complications compared to C-GC in patients with PAI. Moreover, TBS seems to play a pivotal role in the mediation of the relationship between glucocorticoid treatment regimens and fracture risk.
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This study focuses on the dissolution process and surface characterization of amosite fibres following interaction with a mimicked Gamble's solution at a pH of 4.5 and T = 37 °C, up to 720 h. To achieve this, a multi-analytical approach was adopted, and the results were compared to those previously obtained on a sample of asbestos tremolite and UICC crocidolite, which were investigated under the same experimental conditions. Combining surface chemical data obtained by XPS with cation release quantified by ICP-OES, an incongruent behaviour of the fibre dissolution was highlighted for amosite fibres, similarly to asbestos tremolite and UICC crocidolite. In particular, a preferential release of Mg and Ca from the amphibole structure was observed, in agreement with their Madelung site energies. Notably, no Fe release from amosite fibres was detected in our experimental conditions (pH of 4.5 and atmospheric pO2), despite the occurrence of Fe(II) at the M(4) site of the amphibole structure, where cations are expected to be rapidly leached out during mineral dissolution. Moreover, the oxidation of both the Fe centres initially present on the fibre surface and those promoted from the bulk, because of the erosion of the outmost layers, was observed. Since biodurability (i.e., the resistance to dissolution) is one of the most important toxicity parameters, the knowledge of the surface alteration of asbestos possibly occurring in vivo may help to understand the mechanisms at the basis of its long-term toxicity.
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Introduction: The term incremental haemodialysis (HD) means that both dialysis dose and frequency can be low at dialysis inception but should be progressively increased, to compensate for any subsequent reduction in residual kidney function. Policy of the Matera Dialysis Center is to attempt an incremental start of HD without a strict low-protein diet in all patients choosing HD and with urine output (UO) >500 ml/day. The present study aimed at analyzing the results of this policy over the last 20 years. Subjects and methods: The dataset of all patients starting HD between January 1st, 2000 and December 31st, 2019 was retrieved from the local electronic database. Exclusion criteria were: urine output <500 ml/day or follow-up <3 months after the start of the dialysis treatment. Results: A total of 266 patients were retrieved; 64 of them were excluded from the study. The remaining 202 patients were enrolled into the study and subdivided into 3 groups (G1, G2 and G3) according to the frequency of treatment at the start of dialysis: 117 patients (57.9%) started with once-a-week (1HD/wk) (G1); 46 (22.8%) with twice-a-week (2HD/wk) (G2); 39 (19.3%) with thrice-a-week (3HD/wk) dialysis regimen (G3). Patients of G1 remained on 1HD/wk for 11.9 ±14.8 months and then transferred to 2HD/wk for further 13.0 ±20.3 months. Patients of G2 remained on 2HD/wk for 16.7 ±23.2 months. Altogether, 25943 sessions were administered during the less frequent treatment periods instead of 47988, that would have been delivered if the patients had been on 3HD/wk, thus saving 22045 sessions (45.9%). Gross mortality of the entire group was 12.6%, comparable to the mean mortality of the Italian dialysis population (16.2%). Survival at 1 and 5 years was not significantly different among the 3 groups: 94% and 61% (G1); 83% and 39% (G2); 84% and 46% (G3). Conclusions: Our long-term observational study suggests that incremental HD is a valuable option for incident patients. For most of them (80.7%) it is viable for about 1-2 years, with obvious socio-economic benefits and survival rates comparable to that of the Italian dialysis population. However, randomized controlled trials are lacking and therefore urgently needed. If they will confirm observational data, incremental HD will be a new standard of care.
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Fallo Renal Crónico , Humanos , Riñón , Fallo Renal Crónico/terapia , Diálisis Renal/métodos , Nivel de Atención , Tasa de SupervivenciaRESUMEN
Several studies argued that cardiovascular evaluation of patients with nonfunctioning adrenal incidentaloma is of particular importance. Therefore, we aimed to evaluate the possibility of stratifying the cardiometabolic risk using metanephrine levels in this setting of patients. A retrospective cross-sectional study was designed, collecting data of metanephrine values in 828 patients with nonfunctioning adrenal incidentaloma, referred to our Division within the University of Turin between 2007 and 2021. The univariate analysis showed associations between urine metanephrines and cardiometabolic variables/parameters, particularly considering the noradrenaline metabolite. At the univariate regression, normetanephrine was associated with metabolic syndrome (OR = 1.13, p = 0.002), hypertensive cardiomyopathy (OR = 1.09, p = 0.026), microalbuminuria (OR = 1.14, p = 0.024), and eGFR < 60 mL/min/1.73 m2 (OR = 1.11, p = 0.013), while metanephrine was associated with microalbuminuria (OR = 1.50, p = 0.008). At multivariate regression, considering all major cardiovascular risk factors as possible confounders, normetanephrine retained a significant association with metabolic syndrome (OR = 1.10, p = 0.037). Moreover, metanephrine retained a significant association with the presence of microalbuminuria (OR = 1.66, p = 0.003). The present study showed a further role for metanephrines in the cardiovascular risk stratification of patients with nonfunctioning adrenal incidentaloma. Individuals with high levels of these indirect markers of sympathetic activity should be carefully monitored and may benefit from an aggressive treatment to reduce their additional cardiometabolic burden.
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Neoplasias de las Glándulas Suprarrenales , Hipertensión , Síndrome Metabólico , Feocromocitoma , Neoplasias de las Glándulas Suprarrenales/complicaciones , Neoplasias de las Glándulas Suprarrenales/epidemiología , Estudios Transversales , Humanos , Hipertensión/complicaciones , Hipertensión/epidemiología , Síndrome Metabólico/complicaciones , Síndrome Metabólico/epidemiología , Metanefrina , Normetanefrina , Feocromocitoma/complicaciones , Feocromocitoma/epidemiología , Estudios RetrospectivosRESUMEN
BACKGROUND: During pregnancy metabolic disorders that affect differently the fetus, are known. These could be early or late disorders. OBJECTIVES: To analyze different biochemical parameters in umbilical cord blood (UCB) of healthy and pathological newborns from mothers with metabolic disorders. MATERIALS AND METHODS: Samples from UCB (121) were analyzed of newborn from mothers with metabolic disorders who attended at Obstetrics Division. Patients were consecutive, prospective and transversally studied. Newborn were classified as healthy (n = 65) and pathological (n = 56). The maternal metabolic disorders were gestational or non-gestational diabetes, glucose intolerance, insulin resistance and/or obesity).The disorders of the pathological newborns were intrauterine growth restriction (IUGR) and/or fetal distress. Glucose (Glu), urea, creatinine, uric acid (UA), total bilirubin (TB), total proteins (TP), albumin (Alb), transaminases (ALT/AST), alkaline-phosphatase (ALP), gammaglutamyltranspeptidase (GGT), creatinkinasa (CK), lactatedehydrogenase, amylase (amy), pseudocholinesterase, iron, calcium, phosphorus, magnesium (Mg), sodium, potassium, chlorine, cholesterol (Chol), HDL-Chol, LDL-Chol, triglycerides (TG), high sensitivity C reactive protein (hsCRP) were determined by recommended methods. T-Student's and Mann Withney tests were applied, p < .05. RESULTS: Pathological neonates (n: 56) showed a significant decrease in maternal gestation weeks (GW) and in newborn weight (NW) with respect to healthy newborns (n: 65) from mothers with metabolic disorders (p < .0001). Pathological neonates from mothers with metabolic pathologies (n: 56) showed significant increases in Chol, TG, TB (p < .01), LDL-Chol, UA, Mg, hsCRP, ALP levels (p < .05) and significant decreases in TP, Alb (p < .0001) and Glu, ALT, CK, GGT, amy (p < .05) in UCB with respect to healthy newborns. CONCLUSIONS: In pathological newborn, the decrease in GW and NW would be related to IUGR that accompany these metabolic disorders. The increases observed of the analyzed parameters would be related to cellular destruction associated to maternal pathology and decreases of the parameters to IUGR with hepatic immaturity.
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Enfermedades Metabólicas , Complicaciones del Embarazo , Embarazo , Femenino , Recién Nacido , Humanos , Sangre Fetal/metabolismo , Proteína C-Reactiva/metabolismo , Estudios Prospectivos , Triglicéridos , LDL-Colesterol , Retardo del Crecimiento Fetal , Colesterol , Ácido Úrico , gamma-Glutamiltransferasa , Complicaciones del Embarazo/metabolismoRESUMEN
OBJECTIVE: This study aimed to evaluate the reliability of simple and corrected aldosterone indices for assessing the selectivity and lateralization of adrenal vein sampling (AVS) in patients with primary aldosteronism. METHODS: Data of all consecutive patients with primary aldosteronism who underwent AVS for subtype diagnosis, followed at two Italian referral centers, were analyzed retrospectively. RESULTS: AVS achieved bilateral selectivity in 112/144 patients. Unilateral disease was diagnosed in 60 cases (53.6%) and idiopathic hyperaldosteronism in 52 individuals (46.4%). The aldosterone index (aldosterone ratio between an adrenal vein and the inferior vena cava) showed a high accuracy in predicting selectivity, compared to a cortisol selectivity index of 1.1, and a moderate accuracy, compared to cortisol cut-offs of 2 and 3. The simple aldosterone index showed a moderate accuracy in predicting ipsi/contralateral aldosterone hypersecretion, while lesion side- and hypokalemia-corrected aldosterone index revealed a significant improvement in predicting ipsi/contralateral disease. Moreover, the comparative aldosterone index (aldosterone ratio in the dominant vs the non-dominant adrenal vein) revealed a high accuracy in predicting unilateral primary aldosteronism. For an immediate clinical application of our results, the adjusted cut-offs were calculated, according to the Youden's criterion and to a pre-established specificity of 90%, for all possible combinations of lesion side at imaging and presence/absence of hypokalemia. CONCLUSIONS: This study demonstrated the diagnostic accuracy of simple and clinical-/imaging-corrected aldosterone indices for adrenal vein sampling in subtype diagnosis of primary aldosteronism and suggests the potential application of these tools to select patients for adrenalectomy when standard indices cannot be performed.
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Hiperaldosteronismo , Hipopotasemia , Aldosterona , Humanos , Hidrocortisona , Hiperaldosteronismo/diagnóstico , Hiperplasia , Reproducibilidad de los Resultados , Estudios RetrospectivosRESUMEN
AIM: Hereditary hemochromatosis (HH) is a group of inherited disorders that causes a slow and progressive iron deposition in diverse organs, particularly in the liver. Iron overload induces oxidative stress and tissue damage. Coenzyme Q10 (CoQ10) is a cofactor in the electron-transport chain of the mitochondria, but it is also a potent endogenous antioxidant. CoQ10 interest has recently grown since various studies show that CoQ10 supplementation may provide protective and safe benefits in mitochondrial diseases and oxidative stress disorders. In the present study we sought to determine CoQ10 plasma level in patients recently diagnosed with HH and to correlate it with biochemical, genetic, and histological features of the disease. METHODS: Plasma levels of CoQ10, iron, ferritin, transferrin and vitamins (A, C and E), liver tests (transaminases, alkaline phosphatase and bilirubin), and histology, as well as three HFE gene mutations (H63D, S654C and C282Y), were assessed in thirty-eight patients (32 males, 6 females) newly diagnosed with HH without treatment and in twenty-five age-matched normolipidemic healthy subjects with no HFE gene mutations (22 males, 3 females) and without clinical or biochemical signs of iron overload or liver diseases. RESULTS: Patients with HH showed a significant decrease in CoQ10 levels respect to control subjects (0.31⯱â¯0.03 µM vs 0.70⯱â¯0.06 µM, pâ¯<â¯0.001, respectively) independently of the genetic mutation, cirrhosis, transferrin saturation, ferritin level or markers of hepatic dysfunction. Although a decreasing trend in CoQ10 levels was observed in patients with elevated iron levels, no correlation was found between both parameters in patients with HH. Vitamins C and A levels showed no changes in HH patients. Vitamin E was significantly decreased in HH patients (21.1⯱â¯1.3 µM vs 29.9⯱â¯2.5 µM, pâ¯<â¯0.001, respectively), but no correlation was observed with CoQ10 levels. CONCLUSION: The decrease in CoQ10 levels found in HH patients suggests that CoQ10 supplementation could be a safe intervention strategy complementary to the traditional therapy to ameliorate oxidative stress and further tissue damage induced by iron overload.
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Ataxia , Hemocromatosis , Enfermedades Mitocondriales , Debilidad Muscular , Ubiquinona/deficiencia , Ataxia/epidemiología , Estudios de Casos y Controles , Femenino , Hemocromatosis/sangre , Hemocromatosis/epidemiología , Hemocromatosis/genética , Humanos , Masculino , Enfermedades Mitocondriales/epidemiología , Debilidad Muscular/epidemiología , Ubiquinona/análogos & derivados , Ubiquinona/sangreRESUMEN
BACKGROUND: The pancreas is a mixed gland that takes part in the digestion of nutrients and in the homeostasis ofglycemia. Chronic pancreopathy is the cause of secretory insufficiency, characterized by an inflammatory process that leads to fibrosis of the pancreas, with a progressive loss of both exocrine and endocrine functions of the gland. OBJECTIVE: To study both the exocrine and endocrine pancreatic relationship in patients with pancreatopathies and other non-pancreatic digestive alterations, by means of serum pancreolauril (sPL) and oral glucose tolerance tests (OGTT). Glycemia and insulin, basal and at 30, 60 and 120 minutes; amylase and lipase; and the HOMA index (homeostatic model) were determined in serum. MATERIAL AND METHODS: Thirty-two patients were evaluated: normal OGTT (n=11, control group) and pathologic OGTT (n=21). From the latter group, a subgroup (n=11) with a diagnosis of chronic pancreatitis (CP) was studied. RESULTS: Patients with pathologic OGTT in relation with normal OGTT presented a significant increase of glycemia at the four periods of time and of insulin at 120 minutes (P < 0.05), and a significant decrease of sPL (P < 0.05). In patients with CP, men were more than women, and all of them presented a pathologic OGTT and the sPL was significantly lower (P < 0.001). CONCLUSION: By the biochemical tests used, pancreas functionality corresponds with a close relationship between exocrine and endocrine pancreas. Thus, we suggest the use of the sPL test as a helpful tool for the diagnosis of CP.
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Fluoresceínas , Prueba de Tolerancia a la Glucosa , Glucosa/análisis , Páncreas Exocrino/fisiopatología , Pancreatitis Crónica/sangre , Amilasas/sangre , Estudios de Casos y Controles , Femenino , Homeostasis , Humanos , Lipasa/sangre , Masculino , Persona de Mediana Edad , Pruebas de Función Pancreática/métodos , Pancreatitis Crónica/diagnóstico , Pancreatitis Crónica/fisiopatologíaRESUMEN
INTRODUCTION: Urea distribution volume (V) can be assessed in different ways, among them the anthropometric Watson Volume (VW). However, many studies have shown that VW does not coincide with V and that the latter can be more accurately estimated with other methods. The present multicentre study was designed to answer the question: what V to choose to assess online Kt/V? MATERIALS AND METHODS: Pre- and postdialysis blood urea nitrogen concentrations and the usual input data set for urea kinetic modelling were obtained for a single dialysis session in 201 Caucasian patients treated in 9 Italian dialysis units. Only dialysis machines measuring ionic dialysance (ID) were utilized. ID reflects very accurately the mean effective dialyser urea clearance (Kd). Six different V values were obtained: the first one was VW; the second one was computed from the equation established by the HEMO Study to predict the single pool-adjusted modelled V from VW (VH) (Daugirdas JT et al. KI 64: 1108, 2003); the others were estimated kinetically as: 1. V_ID, in which ID is direct input in the in the double pool variable volume (dpVV) calculation by means of the Solute-solver software; 2. V_Kd, in which the estimated Kd is direct input in the dpVV calculation by means of the Solute-solver software; 3. V_KTV, in which V is calculated by means of the second generation Daugirdas equation; 4. V_SPEEDY, in which ID is direct input in the dpVV calculation by means of the SPEEDY software able to provide results quite similar to those provided by Solute-solver. RESULTS: Mean± SD of the main data are reported: measured ID was 190.6 ± 29.6 mL/min, estimated Kd was 211.6 ± 29.0 mL/min. The relationship between paired data was poor (R2 = 0.34) and their difference at the Bland-Altman plot was large (21 ± 27 mL/min). VW was 35.3 ± 6.3 L, VH 29.5 ± 5.5, V_ID 28.99 ± 7.6 L, V_SPEEDY 29.4 ± 7.6 L, V_KTV 29.7 ± 7.0 L. The mean ratio VW/V_ID was 1.22, (i.e. VW overestimated V_ID by about 22%). The mean ratio VH/V_ID was 1.02 (i.e. VH overestimated V_ID by only 2%). The relationship between paired data of V_ID and VW was poor (R2 = 0.48) and their mean difference at the Bland-Altman plot was very large (- 6.39 ± 5.59 L). The relationship between paired data of V_ID and VH was poor (R2 = 47) and their mean difference was small but with a large SD (- 0.59 ± 5.53 L). The relationship between paired data of V_ID and V_SPEEDY was excellent (R2 = 0.993) and their mean difference at the Bland-Altman plot was very small (- 0.54 ± 0.64 L). The relationship between paired data of V_ID and V_KTV was excellent (R2 = 0.985) and their mean difference at the Bland-Altman plot was small (- 0.85 ± 1.06 L). CONCLUSIONS: V_ID can be considered the reference method to estimate the modelled V and then the first choice to assess Kt/V. V_SPEEDY is a valuable alternative to V_ID. V_KTV can be utilized in the daily practice, taking also into account its simple way of calculation. VW is not advisable because it leads to underestimation of Kt/V by about 20%.
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Soluciones para Hemodiálisis , Diálisis Renal , Insuficiencia Renal/terapia , Urea/metabolismo , Anciano , Nitrógeno de la Urea Sanguínea , Femenino , Humanos , Masculino , Persona de Mediana Edad , Insuficiencia Renal/metabolismo , Factores de TiempoRESUMEN
AIM: Intrahepatic cholestasis of pregnancy (ICP) is considered a high-risk condition because it may have serious consequences for the fetus health. ICP is characterized by the accumulation of bile acids in maternal serum which contribute to an imbalance between the production of reactive oxygen species and the antioxidant defenses increasing the oxidative stress experienced by the fetus. Previously, it was reported a significant decrease in plasma coenzyme Q10 (CoQ10) in women with ICP. CoQ10 is a redox substance integrated in the mitochondrial respiratory chain and is recognized as a potent antioxidant playing an intrinsic role against oxidative damage. The objective of the present study was to investigate the levels of CoQ10 in umbilical cord blood during normal pregnancy and in those complicated with ICP, all of them compared to the maternal ones. METHODS: CoQ10 levels and bile acid levels in maternal and umbilical cord blood levels during normal pregnancies (n=23) and in those complicated with ICP (n=13), were investigated. RESULTS: A significant decrease in neonate CoQ10 levels corrected by cholesterol (0.105±0.010 vs. 0.069±0.011, P<0.05, normal pregnancy vs. ICP, respectively), together with an increase of total serum bile acids (2.10±0.02 vs. 7.60±2.30, P<0.05, normal pregnancy vs. ICP, respectively) was observed. CONCLUSIONS: A fetus from an ICP mother is exposed to a greater risk derived from oxidative damage. The recognition of CoQ10 deficiency is important since it could be the starting point for a new and safe intervention strategy which can establish CoQ10 as a promising candidate to prevent the risk of oxidative stress.
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Ataxia/sangre , Ácidos y Sales Biliares/sangre , Colestasis Intrahepática/sangre , Sangre Fetal/química , Enfermedades Mitocondriales/sangre , Debilidad Muscular/sangre , Complicaciones del Embarazo/sangre , Ubiquinona/análogos & derivados , Ubiquinona/deficiencia , Adulto , Ataxia/diagnóstico , Biomarcadores/sangre , Peso al Nacer , Colesterol/sangre , Ácido Cólico/sangre , Estudios Transversales , Femenino , Feto/metabolismo , Edad Gestacional , Humanos , Recién Nacido , Enfermedades Mitocondriales/diagnóstico , Debilidad Muscular/diagnóstico , Oxidación-Reducción , Estrés Oxidativo , Embarazo , Estudios Prospectivos , Especies Reactivas de Oxígeno/metabolismo , Ubiquinona/sangre , Adulto JovenRESUMEN
Acetaminophen (APAP) administration at therapeutic doses is safe, however overdosing produces hepatocellular injury via a multifactorial mechanism(s) that involves generation of reactive oxygen species (ROS), being the most common cause of acute liver failure (ALF) in the northern hemisphere. Brain alterations induced by APAP intoxication are usually considered secondary to hepatic encephalopathy development due to ALF. Although APAP is primarily metabolized in the liver, it is also distributed and metabolized homogeneously in the brain, affecting brain redox status. Nevertheless, comprehensive studies on the potential of APAP intoxication to produce brain toxicity are scarce. The aim of this study was to characterize the direct toxic effects of APAP in different regions of the brain and on behavior in rats where the magnitude of hepatotoxicity produced is not associated with ALF. The present work demonstrates that APAP intoxication producing hepatotoxicity, but not ALF in rats, is associated with marked hypolocomotion. Our studies also suggest that selective downregulation in dopamine levels in brain areas that regulate motor activity may be responsible, in part, for the decreased locomotion observed with APAP treatment. Furthermore, we observed that the brain histoarchitecture is conserved and that edema is not present. However, an increase in oxidative stress, reactive astrogliosis and a decrease in neuron processes are the main features observed in APAP-intoxicated animals. These effects might be partly due to direct toxic effects of APAP in brain, since the same reactive astrogliosis observed in rats was also observed in rat primary astrocyte cultures exposed to APAP.
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Acetaminofén/toxicidad , Analgésicos no Narcóticos/toxicidad , Encéfalo/efectos de los fármacos , Neuronas Dopaminérgicas/efectos de los fármacos , Gliosis/inducido químicamente , Locomoción/efectos de los fármacos , Animales , Animales Recién Nacidos , Astrocitos/efectos de los fármacos , Astrocitos/metabolismo , Astrocitos/patología , Encéfalo/metabolismo , Encéfalo/patología , Células Cultivadas , Neuronas Dopaminérgicas/metabolismo , Neuronas Dopaminérgicas/patología , Femenino , Gliosis/metabolismo , Locomoción/fisiología , Masculino , Síndromes de Neurotoxicidad/metabolismo , Síndromes de Neurotoxicidad/patología , Estrés Oxidativo/efectos de los fármacos , Estrés Oxidativo/fisiología , Ratas , Ratas WistarRESUMEN
Type 2 diabetes is characterized by peripheral insulin resistance, pancreatic beta-cells dysfunction, and decreased beta-cell mass with increased rate of apoptosis. Chronic exposure to high levels of free fatty acids (FFAs) has detrimental effects on beta-cell function and survival. FFAs have adverse effects on mitochondrial function, with a consequent increase in the production of reactive oxygen species. Hepatocyte growth factor (HGF) plays a critical role in promoting beta-cell survival. In the present study, we investigated whether HGF was capable of protecting beta-cells from death induced by prolonged exposure to FFAs. RINm5F cell line was cultured in the presence of FFAs (oleate:palmitate 2:1) for 72 h in order to induce apoptosis. Simultaneous administration of HGF and FFAs significantly suppressed the impaired insulin secretion and FFA-induced apoptosis. Specifically, HGF exerted its protective effect by counteracting: (i) the overproduction of either hydrogen peroxide and superoxide anion, (ii) the reduction of intracellular gamma-glutamylcysteinylglycine level, and (iii) the depolarization of mitochondrial membrane, induced by prolonged FFAs exposure. These effects appear to be mediated by bcl-2 and phosphatidylinositol 3 kinase (PI3K)/Akt pathways. Indeed, HGF increased mRNA and protein expression of bcl-2 downregulated by FFAs-treatment; moreover, pre-treatment with the specific PI3-kinase inhibitor LY294002, significantly abolished the protective effect of HGF. In conclusion, in rat insulin-producing RINm5F cells, HGF exerts its prosurvival effect by counteracting the increased intracellular oxidative stress and, consequently, by inhibiting apoptosis induced by chronic exposure to FFAs.
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Apoptosis/fisiología , Ácidos Grasos no Esterificados/antagonistas & inhibidores , Factor de Crecimiento de Hepatocito/fisiología , Estrés Oxidativo/fisiología , Animales , Línea Celular , Ácidos Grasos no Esterificados/fisiología , Células Secretoras de Insulina/metabolismo , RatasRESUMEN
The conversion of proteins into amyloid fibrils and other amyloid-like aggregates is closely connected to the onset of a series of age-related pathologies. Upon changes in environmental conditions, amyloid-like aggregates may also undergo disassembly into oligomeric aggregates, the latter being recognized as key effectors in toxicity. This indicates new possible routes for in vivo accumulation of toxic species. In the light of the recognized implication of α-Synuclein (αSN) in Parkinson's disease, we present an experimental study on supramolecular assembly of αSN with a focus on stability and disassembly paths of such supramolecular aggregate species. Using spectroscopic techniques, two-photon microscopy, small-angle X-ray scattering and atomic force microscopy, we report evidences on how the stability of αSN amyloid-like aggregates can be altered by changing solution conditions. We show that amyloid-like aggregate formation can be induced at high temperature in the presence of trifluoroethanol (TFE). Moreover, sudden disassembly or further structural reorganisation toward higher hierarchical species can be induced by varying TFE concentration. Our results may contribute in deciphering fundamental mechanisms and interactions underlying supramolecular clustering/dissolution of αSN oligomers in cells.
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Agregado de Proteínas/efectos de los fármacos , Trifluoroetanol/farmacología , alfa-Sinucleína/química , Amiloide/química , Humanos , Estabilidad Proteica , Análisis Espectral , Temperatura , alfa-Sinucleína/efectos de los fármacosRESUMEN
Aß(1-40) peptide supramolecular assembly and fibril formation processes are widely recognized to have direct implications in the progression of Alzheimer's disease. The molecular basis of this biological process is still unknown and there is a strong need of developing effective strategies to control the occurring events. To this purpose the exploitation of small molecules interacting with Aß aggregation represents one of the possible routes. Moreover, the use specific labeling has represented so far one of the most common and effective methods to investigate such a process. This possibility in turn rests on the reliability of the probe/labels involved. Here we present evidences of the effect of Thioflavin T (ThT), a worldwide used fluorescent dye to monitor amyloid growth, on the Aß(1-40) conformation, stability and aggregation. By combining experimental information and Molecular Dynamics simulation results, we show that the presence of ThT in solution affects peptide conformation inducing peculiar supramolecular association. In particular ThT interactions with specific Aß(1-40) residues promote a rigid partially-folded conformation which shifts the balance between different species in solution toward a more aggregation-prone ensemble of peptides, leading to aggregation. Our findings suggest ways for developing strategies to reverse and block aggregation or to stimulate supramolecular assembly and consequently reduce the presence of transient oligomers. This investigation underlines the need of developing label-free techniques for unbiased quantitative studies of Aß(1-40) aggregation processes.
Asunto(s)
Péptidos beta-Amiloides/metabolismo , Colorantes Fluorescentes/metabolismo , Fragmentos de Péptidos/metabolismo , Agregado de Proteínas/efectos de los fármacos , Tiazoles/metabolismo , Enfermedad de Alzheimer/metabolismo , Secuencia de Aminoácidos , Péptidos beta-Amiloides/química , Péptidos beta-Amiloides/ultraestructura , Benzotiazoles , Recuperación de Fluorescencia tras Fotoblanqueo , Colorantes Fluorescentes/análisis , Humanos , Simulación de Dinámica Molecular , Datos de Secuencia Molecular , Fragmentos de Péptidos/química , Fragmentos de Péptidos/ultraestructura , Agregación Patológica de Proteínas/metabolismo , Conformación Proteica/efectos de los fármacos , Multimerización de Proteína/efectos de los fármacos , Estabilidad Proteica/efectos de los fármacos , Estructura Secundaria de Proteína/efectos de los fármacos , Tiazoles/análisisRESUMEN
Gastrointestinal lesions have been extensively reported in wild and captive marine mammals. However, their etiology remains unclear. In humans and other animals, chronic gastritis and peptic ulcers have been associated with Helicobacter sp. Therefore, the aim of our study was to investigate the presence of Helicobacter sp. in the gastric juice, dental plaque, and saliva of marine mammals living in a controlled environment. Five dolphins (Tursiops gephyreus), one killer whale (Orcinus orca), one false killer whale (Pseudorca crassidens), three sea lions (Otaria flavescens), two elephant seals (Mirounga leonina), and two fur seals (Arctocephalus australis) were studied. Saliva, dental plaque, and gastric juice samples were examined for Helicobacter sp. using polymerase chain reaction. None of the gastric juice or saliva samples were positive for Helicobacter sp. However, Helicobacter sp. DNA was detected in dental plaque from two dolphins, suggesting the oral cavity might be a reservoir of this bacterium.
Asunto(s)
Placa Dental/veterinaria , Delfines , Infecciones por Helicobacter/veterinaria , Helicobacter/aislamiento & purificación , Animales , Animales de Zoológico , ADN Bacteriano/análisis , Placa Dental/microbiología , Femenino , Jugo Gástrico/química , Jugo Gástrico/microbiología , Gastritis/microbiología , Gastritis/veterinaria , Helicobacter/genética , Infecciones por Helicobacter/microbiología , Masculino , Reacción en Cadena de la Polimerasa/veterinaria , Saliva/microbiología , PhocidaeRESUMEN
Until now, biochemical parameter for diagnosis of intrahepatic cholestasis of pregnancy (ICP) mostly used is the rise of total serum bile acids (TSBA) above the upper normal limit of 11 µM. However, differential diagnosis is very difficult since overlapped values calculated on bile acids determinations, are observed in different conditions of pregnancy including the benign condition of pruritus gravidarum. The aim of this work was to determine the better markers in ICP for a precise diagnosis together with parameters associated with severity of symptoms and treatment evaluation. Serum bile acid profiles were evaluated using capillary electrophoresis in 38 healthy pregnant women and 32 ICP patients and it was calculated the sensitivity, specificity, accuracy, predictive values and the relationships of certain individual bile acids in pregnant women in order to replace TSBA determinations. The evaluation of the results shows that LCA and UDCA/LCA ratio provided information for a more complete and accurate diagnosis and evaluation of ICP than calculation of solely TSBA levels in pregnant women.
RESUMEN
Fibrillogenesis of the small peptide Aß(1-40) is considered to be the hallmark of Alzheimer's disease. Some evidence indicates small oligomers, rather than mature fibrils, as the key cytotoxic agents. The fluorescent dye Thioflavin T (ThT) is often used to detect amyloid deposits in both in vivo and in vitro experiments, and it is used to study kinetic measurements, under the fundamental hypothesis that this probe does not influence the aggregation processes. We report experimental data showing that ThT may promote the Aß(1-40) peptide amyloid aggregation changing solvent-peptide interactions and stabilizing more ordered ß-like conformation. This finding has a two-fold importance: It is a fundamental warning in all fibrillation experiments where ThT is used as fluorescent probe, and it suggests that ThT, accelerating fibril formation, could be used to reduce the presence of transient small oligomers, thus interfering with the pathogenic impact of Aß peptide.
RESUMEN
El deporte exige de quienes lo practican una adaptación, entrenamiento y buen estado físico. El objetivo del trabajo fue estudiar en suero/plasma de individuos jugadores de fútbol de élite (n=32) y no entrenados (n=16), los perfiles hematológico, endocrinológico y de química clínica, relacionar los hallazgos bioquímicos con la fisiopatología deportiva y evaluar la probable implicancia clínica de los resultados. De acuerdo con los resultados obtenidos se observó disminución significativa en: hematocrito, hierro, plaquetas y bilirrubina (expansión plasmática fisiológica); magnesio (consumo enzimático); y proteínas y glucemia (incremento del metabolismo energético y recambio proteico). No se detectaron cambios significativos en el perfil endocrinológico (TSH disminuida, mayor eficacia de la hormona) y perfil lipídico (aumento de HDL y disminución de LDL; efecto protector de las lipoproteínas). Se observó un aumento significativo en: calcio (mayor disponibilidad); urea (metabolismo proteico aumentado); y aldolasa y creatinquinasa (lisis fibra muscular entrenada). Se concluye que la creatinquinasa es el marcador de pertenencia al grupo de élite; se debería implementar un valor de referencia diferente para esta población de deportistas ya que el deporte es objeto de estudio del laboratorio bioquímico; y la implementación de los conocimientos científicos en forma práctica y adecuada permite ayudar al profesional médico deportólogo a tomar decisiones oportunas y acertadas.