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A laser ion source coupled with a radio frequency quadrupole linac accelerator is being proposed as a suitable system for the production of a low energy, high-current stable lithium beam. In order to maximize the lithium yield, plasmas generated by laser ablation of different materials based on lithium (Li, LiOH, and LiNbO3) have been characterized by using a Faraday cup and an electrostatic ion analyzer in the time of flight configuration. A wide range of laser power density has been investigated (109-1012 W/cm2) using two Nd:YAG lasers operating at different wavelengths (1064 nm and 532 nm), pulse durations (6 ns and 17 ns), and maximum energies (1400 mJ and 210 mJ). This paper outlines the pros and cons of the investigated materials by studying how the ion energy, yields, and charge state distributions are modified when the laser power density is changed. Considerable attention has been paid to the higher charge states of oxygen, which may occur with the same mass-to-charge ratio of Li3+. The analysis has evidenced that LiNbO3 represents a valid target since it allows minimizing the O6+/7Li3+ ratio down to 2.5% by using a laser power density of 1.8 × 1010 W/cm2. For such a condition, a Li3+ current of 1.4 mA/cm2 has been measured.
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We are developing a laser ion source to provide a high brightness multi-charged heavy ion beam as a part of the heavy ion beam probe system, which will be used to diagnose plasma potential in the Ring Trap 1 device at the University of Tokyo. As a probe beam, Nb2+ was selected, and a detailed laser irradiation condition was explored. It was found that the laser power density of 1.2 × 109 W/cm2 gives the maximum particle number of Nb2+ per laser energy from a niobium foil target. Essential ablation plasma parameters to design the laser ion source were also obtained. The expected beam current was more than 12 mA/cm2, with a pulse width of 3.1 µs at 200 mm away from the target.
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Single-antigen bead (SAB) platform permits the identification of antibodies not detectable by complement-dependent lymphocytotoxicity test, but their clinical significance is not completely understood. The aim of this study was to evaluate whether the presence of pretransplant SAB-detected antibodies is associated with the development of allograft failure. This is a single-center cohort study with 10-year follow-up in which 573 kidney recipients with negative pretransplant complement-dependent lymphocytotoxicity crossmatch who received transplants at the Kidney Transplant Center of Policlinico, Milan, from deceased donors between 1996 and 2005 were evaluated. Pretransplant plasma samples were retrospectively analyzed by SAB assay. Survival analyses were performed to assess the risk of allograft failures by SAB-detected antibodies. Pretransplant antibodies were found in 160 (28.0%) recipients, of whom 42 subsequently developed an allograft failure for a survival rate of 70.9% (95% confidence interval [CI), 63.5-78.4). Among those without antibodies, 58 (14.0%) returned to dialysis with a survival rate of 84.7% (95% CI, 81.0-88.4). In Cox regression analyses, patients with SAB-positivity had 2-fold higher risk of allograft failure than those who were SAB-negative (hazard ratio, 2.07; 95% CI, 1.39-2.79). Results did not change after adjustment for putative confounders. In conclusion, in this single-center cohort, 10-year allograft survival rate was significantly influenced by the presence of SAB-detected antibodies.
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Supervivencia de Injerto/inmunología , Antígenos HLA/inmunología , Prueba de Histocompatibilidad/métodos , Isoanticuerpos/inmunología , Trasplante de Riñón/métodos , Adulto , Estudios de Cohortes , Femenino , Rechazo de Injerto/inmunología , Humanos , Isoanticuerpos/análisis , Masculino , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , Estudios RetrospectivosRESUMEN
Essentials Data on product-related immunogenicity in previously treated haemophilia A patients is scarce. A systematic review and meta-analysis of all currently available evidence was conducted. The overall incidence rate was 2.06 per 1000 person-years (95% confidence interval: 1.06-4.01). Some recombinant factor VIII products were associated with increased immunogenicity. SUMMARY: Background Patients with severe hemophilia A who have been treated extensively with factor VIII products have a low but potentially serious risk of inhibitor development. It is unknown why these patients develop inhibitors, and data on product-related immunogenicity are scarce. Aims To summarize the currently available evidence on the relationship between inhibitor development and recombinant FVIII product type in previously treated patients (PTPs) with severe hemophilia A. Methods Longitudinal studies were included that reported on de novo inhibitor formation in patients with baseline FVIII activity levels of < 0.02 IU mL-1 who had been treated with FVIII for at least 50 days. Pooled incidence rates of inhibitor development according to product types were calculated with a random intercept Poisson regression model. Results Forty-one independent cohorts were included; 39 patients developed de novo inhibitors during 19 157 person-years of observation. The overall incidence rate was 2.06 per 1000 person-years, with a 95% confidence interval (CI) of 1.06-4.01. According to product type, the pooled incidence rates were 0.99 (95% CI 0.37-2.70) per 1000 person-years for patients treated with Advate, 5.86 (95% CI 0.25-134.92) per 1000 person-years for those treated with Kogenate/Helixate, 1.35 (95% CI 0.66-2.77) per 1000 person-years for those treated with Kogenate FS/Helixate NexGen, 12.05 (95% CI 1.53-94.78) per 1000 person-years for those treated with Refacto, and 4.64 (95% CI 0.82-26.43) per 1000 person-years for those treated with Refacto AF. Conclusion These results suggest that some products may be associated with increased immunogenicity. However, the low incidence of inhibitors in PTPs and the differences in study design may cause significant variation in estimates of risk.
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Anticuerpos Neutralizantes/sangre , Coagulantes/inmunología , Coagulantes/uso terapéutico , Factor VIII/inmunología , Factor VIII/uso terapéutico , Hemofilia A/tratamiento farmacológico , Hemostasis/efectos de los fármacos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Coagulantes/efectos adversos , Factor VIII/efectos adversos , Hemofilia A/sangre , Hemofilia A/inmunología , Humanos , Lactante , Recién Nacido , Persona de Mediana Edad , Proteínas Recombinantes/inmunología , Proteínas Recombinantes/uso terapéutico , Medición de Riesgo , Factores de Riesgo , Índice de Severidad de la Enfermedad , Resultado del Tratamiento , Adulto JovenRESUMEN
BACKGROUND: Photoallergic contact dermatitis (PACD) to oxybenzone was reported for the first time in 1980. Oxybenzone is the most common photoallergen in the United States and Canada and the fourth most common .in Europe. There are no studies or data on the prevalence of oxybenzone PACD in Argentina. OBJECTIVE: To determine the proportion of photosensitive patients with PACD to oxybenzone. METHODS: We conducted a descriptive cross-sectional study of 35 patients with photosensitivity reactions confirmed by photopatch testing at the Research Center of Hospital Público San Martín in La Plata, Argentina, in 2015 and 2016. RESULTS: PACD was identified in 6 patients (17.14%). Five of these (14.28%) had at least one positive reaction to oxybenzone in the photopatch test; 4 had a reaction at irradiated sites only (5 J/cm2 UVA) and one had a reaction at both irradiated and nonirradiated sites. CONCLUSIONS: PACD to sunscreens containing oxybenzone is common and is probably underdiagnosed due to a lack of confirmation by photopatch tests or other diagnostic tools. Sensitization rates vary according to region and are influenced by sunscreen ingredients and variations in the use of sunscreen products, cosmetics, and topical drugs.
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Benzofenonas/efectos adversos , Dermatitis Fotoalérgica/epidemiología , Dermatitis Fotoalérgica/etiología , Protectores Solares/efectos adversos , Adulto , Anciano , Argentina/epidemiología , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto JovenRESUMEN
Essentials A residual factor VIII synthesis is likely to be protective towards inhibitor (INH) development. Mutation type-inhibitor risk association was explored in 231 patients with severe hemophilia A. A 2-fold increase in INH development for in silico null vs. non-null mutations was found. A 3.5-fold increase in INH risk for antigen negative vs. antigen positive mutations was found. SUMMARY: Background The type of F8 mutation is the main predictor of inhibitor development in patients with severe hemophilia A. Mutations expected to allow residual synthesis of factor VIII are likely to play a protective role against alloantibody development by inducing immune tolerance. According to the expected full or partial impairment of FVIII synthesis, F8 variants are commonly classified as null and non-null. Objectives To explore the mutation type-inhibitor risk association in a cohort of 231 patients with severe hemophilia A enrolled in the Survey of Inhibitors in Plasma-Product Exposed Toddlers (SIPPET) randomized trial. Methods The genetic defects in these patients, consisting of inversions of intron 22 (n = 110) and intron 1 (n = 6), large deletions (n = 16), and nonsense (n = 38), frameshift (n = 28), missense (n = 19) and splicing (n = 14) variants, of which 34 have been previously unreported, were reclassified according to two additional criteria: the functional effects of missense and splicing alterations as predicted by multiple in silico analyses, and the levels of FVIII antigen in patient plasma. Results A two-fold increase in inhibitor development for in silico null mutations as compared with in silico non-null mutations (hazard ratio [HR] 2.08, 95% confidence interval [CI] 0.84-5.17) and a 3.5-fold increase in inhibitor development for antigen-negative mutations as compared with antigen-positive mutations (HR 3.61, 95% CI 0.89-14.74] were found. Conclusions Our findings confirm an association between the synthesis of minute amounts of FVIII and inhibitor protection, and underline the importance of investigating the residual FVIII antigen levels associated with causative variants in order to understand their clinical relevance.
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Anticuerpos Neutralizantes/inmunología , Factor VIII/genética , Factor VIII/inmunología , Hemofilia A/genética , Hemofilia A/inmunología , Isoanticuerpos/inmunología , Mutación , África , Anticuerpos Neutralizantes/sangre , Asia , Análisis Mutacional de ADN , Europa (Continente) , Factor VIII/metabolismo , Factor VIII/uso terapéutico , Predisposición Genética a la Enfermedad , Hemofilia A/sangre , Hemofilia A/tratamiento farmacológico , Humanos , Isoanticuerpos/sangre , América del Norte , Fenotipo , Valor Predictivo de las Pruebas , Factores de Riesgo , Índice de Severidad de la Enfermedad , América del Sur , Factores de Tiempo , Resultado del TratamientoRESUMEN
Essentials Recombinant factor VIII (rFVIII) was contrasted with plasma-derived FVIII (pdFVIII). In previously untreated patients with hemophilia A, rFVIII led to more inhibitors than pdFVIII. Inhibitors with rFVIII developed earlier, and the peak rate was higher than with pdFVIII. Inhibitors with rFVIII were more severe (higher titre) than with pdFVIII. SUMMARY: Background The development of neutralizing antibodies (inhibitors) against factor VIII (FVIII) is the most severe complication in the early phases of treatment of severe hemophilia A. Recently, a randomized trial, the Survey of Inhibitors in Plasma-Product Exposed Toddlers (SIPPET) demonstrated a 2-fold higher risk of inhibitor development in children treated with recombinant FVIII (rFVIII) products than with plasma-derived FVIII (pdFVIII) during the first 50 exposure days (EDs). Objective/Methods In this post-hoc SIPPET analysis we evaluated the rate of inhibitor incidence over time by every 5 EDs (from 0 to 50 EDs) in patients treated with different classes of FVIII product, made possible by a frequent testing regime. Results The highest rate of inhibitor development occurred in the first 10 EDs, with a large contrast between rFVIII and pdFVIII during the first 5 EDs: hazard ratio 3.14 (95% confidence interval [CI], 1.01-9.74) for all inhibitors and 4.19 (95% CI, 1.18-14.8) for high-titer inhibitors. For patients treated with pdFVIII, the peak of inhibitor development occurred later (6-10 EDs) and lasted for a shorter time. Conclusion These results emphasize the high immunologic vulnerability of patients during the earliest exposure to FVIII concentrates, with the strongest response to recombinant FVIII products.
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Anticuerpos Neutralizantes/sangre , Coagulantes/administración & dosificación , Factor VIII/administración & dosificación , Hemofilia A/tratamiento farmacológico , Anticuerpos Neutralizantes/inmunología , Preescolar , Coagulantes/efectos adversos , Coagulantes/inmunología , Factor VIII/efectos adversos , Factor VIII/inmunología , Hemofilia A/sangre , Hemofilia A/diagnóstico , Hemofilia A/inmunología , Humanos , Masculino , Ensayos Clínicos Controlados Aleatorios como Asunto , Proteínas Recombinantes/administración & dosificación , Factores de Tiempo , Resultado del TratamientoRESUMEN
Essentials ISTH Bleeding Assessment Tool (ISTH-BAT) is used to assist the diagnosis of bleeding disorders. We examined whether the ISTH-BAT is capable of predicting the risk of future bleeding. 136 subjects were administered the ISTH-BAT and followed for up to four years. The ISTH-BAT score failed to predict the risk of future bleeding. SUMMARY: Background The ISTH Bleeding Assessment Tool (ISTH-BAT) is a diagnostic tool used in subjects with suspected inherited bleeding disorders. Aim To evaluate whether the ISTH-BAT, applied at first work-up in a tertiary-care center, predicts the risk of subsequent bleeding events. Methods This was an observational cohort study including all consecutive subjects, of either sex and any age, referred between 2011 and 2015 because of a suspected bleeding disorder. The analysis was restricted to those with an ISTH-BAT score of ≥ 3. Incidence rates (IRs) of major bleeding (MB) and clinically relevant non-major bleeding (CRNMB) events were calculated as the number of events over accrued person-years. The main analysis was performed with Cox regression analysis, assessing an ISTH-BAT score of ≤ 5 versus a score of > 5, as well as the score as a continuous variable, and various covariates (sex, age, and presence/absence of a final diagnosis). Results One hundred and thirty-six subjects had a median ISTH-BAT score of 4 (range 3-18). Eleven subjects (8.1%) had a bleeding event during follow-up (one MB event; 10 CRNMB events). The overall IR of bleeding events per 100 person-years was 3.7 (95% confidence interval [CI] 1.8-6.6). No difference was observed between subjects with an ISTH-BAT score of ≤ 5 and those with a score of > 5 (hazard ratio [HR] 1.2, 95% CI 0.3-4.6). The results were similar when the ISTH-BAT score was considered as a continuous variable (HR 1.1, 95% CI 0.9-1.4). The IR of bleeding was increased in individuals with a diagnosis of a hemostatic defect (IR of 7.5 per 100 person-years; HR 3.0, 95% CI 0.8-11.8). Conclusions The ISTH-BAT does not identify patients at increased risk of future bleeding events.
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Trastornos de la Coagulación Sanguínea Heredados/diagnóstico , Coagulación Sanguínea , Técnicas de Apoyo para la Decisión , Hemorragia/diagnóstico , Adolescente , Adulto , Trastornos de la Coagulación Sanguínea Heredados/sangre , Trastornos de la Coagulación Sanguínea Heredados/genética , Femenino , Hemorragia/sangre , Hemorragia/genética , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Pronóstico , Recurrencia , Medición de Riesgo , Factores de Riesgo , Factores de Tiempo , Adulto JovenRESUMEN
UNLABELLED: Essentials Plasma of factor XI-deficient patients (FXI-dp) displays enhanced fibrinolysis. We investigated the role of thrombin activatable fibrinolysis inhibitor (TAFI) in 18 FXI-dp. FXI-dp generated less activated TAFI (TAFIa) on clotting challenge and were resistant to TAFIa. TAFI activation and TAFIa resistance correlated with bleeding score and bleeding phenotype. SUMMARY: Background Factor XI (FXI) deficiency, a rare disorder with unpredictable bleeding, has been associated with reduced fibrinolytic resistance as a result of abnormal fibrin density. Objective We investigated the involvement of thrombin-activatable fibrinolysis inhibitor (TAFI) in the increased lysability of FXI-deficient (FXI-def) clots and the role of thrombin. Patients/Methods Eighteen patients with FXI deficiency (1-58%) and 17 matched controls were investigated for fibrinolytic resistance to t-PA, thrombin generation, TAFI activation and response to TAFIa. Results When clotting was induced by 0.5 pm tissue factor (TF), FXI-def plasmas displayed less thrombin and TAFIa generation and shorter lysis time than controls. A 100-fold higher TF concentration (to bypass FXI) abolished the difference in thrombin generation but not in lysis time between patients and controls. Normalization of FXI levels by a FXI concentrate increased thrombin generation but had no effect on the lysis time of FXI-def plasma. Moreover, when clots were induced by purified thrombin and high concentrations of FXa inhibitor, FXI-def plasma still generated less TAFIa and displayed a shorter lysis time than controls. Finally, upon TAFIa addition, the lysis time of FXI-def plasma was prolonged significantly less than that of control plasma, suggesting a TAFIa resistance. TAFIa generation and TAFIa resistance were correlated with the bleeding score, displaying a considerable capacity to discriminate between patients with and without bleeding. Conclusions TAFI pathway impairment, largely caused by a hitherto unknown TAFIa resistance, appears to be one main cause of decreased fibrinolytic resistance in FXI deficiency and might be clinically useful for assessing the bleeding risk of FXI-def patients.
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Deficiencia del Factor XI/sangre , Fibrinólisis/genética , Trombina/química , Adolescente , Adulto , Anciano , Coagulación Sanguínea , Estudios de Casos y Controles , Niño , Preescolar , Factor XI , Femenino , Fibrina/química , Estudios de Seguimiento , Hemorragia , Humanos , Masculino , Persona de Mediana Edad , Fenotipo , Terapia Trombolítica/métodos , Trombomodulina/metabolismo , Trombosis , Activador de Tejido Plasminógeno/química , Adulto JovenRESUMEN
It has been proposed that a neural signature of aware pain perception could be represented by the modulation of gamma-band oscillation (GBO) power induced by nociceptive repetitive laser stimulation (RLS). The aim of our study was to correlate the RLS-induced GBO modulation with the Nociception Coma Scale-Revised (NCS-R) scores (a validated scale assessing possible aware pain perception in patients with chronic disorders of consciousness), in an attempt to differentiate unresponsive wakefulness syndrome (UWS) patients from minimally conscious state (MCS) ones (both of them are awake but exhibit no or limited and fluctuant behavioral signs of awareness and mentation, and low and high NCS-R scores, respectively). In addition, we attempted to identify those among UWS patients who probably experienced pain at covert level (i.e. being aware but unable to show pain-related purposeful behaviors, which are those sustained, reproducible, and voluntary behavioral responses to nociceptive stimuli). Notably, the possibility of clearly differentiating UWS from MCS patients has outmost consequences concerning prognosis (worse in UWS) and adequate pain treatment. RLS consisted in 80 trains of three laser stimuli (delivered at 1Hz), at four different energies, able to evoke Aδ-fiber related laser evoked potentials. After each train, we assessed the NCS-R score. EEG was divided into epochs according to the laser trains, and the obtained epochs were classified in four categories according to the NCS-R score magnitude. We quantified the GBO absolute power for each category. RLS protocol induced a strongly correlated increase in GBO power and NCS-R score (the higher the laser stimulation intensity, the higher the NCS-R, independently of stimulus repetition) in all the MCS patients, thus confirming the presence of aware pain processing. Nonetheless, such findings were present even in five UWS individuals. This could suggest the presence of covert pain processing in such subjects, despite the low NCS-R scores. In conclusion, RSL-induced GBO power evaluation could be helpful in the differential diagnosis between MCS and UWS patients, besides the clinical assessment, and in identifying covert pain perception in some UWS individuals.
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Potenciales Evocados por Láser/fisiología , Percepción del Dolor/fisiología , Estado Vegetativo Persistente/fisiopatología , Adulto , Anciano , Análisis de Varianza , Electroencefalografía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Índice de Severidad de la EnfermedadRESUMEN
BACKGROUND: The formation of ADAMTS13-specific circulating immune complexes (CICs) may be a pathophysiologic mechanism in autoimmune thrombotic thrombocytopenic purpura (TTP), but has not been systematically investigated. OBJECTIVES: (a) To develop an assay for ADAMTS13-specific CICs; (b) to evaluate their prevalence in autoimmune TTP; and (c) to assess their association with ADAMTS13-related measurements and clinical features in autoimmune TTP patients. PATIENTS/METHODS: We developed and validated an ELISA method for ADAMTS13-specific CICs. ADAMTS13-specific CICs were searched for in 55 patients with autoimmune TTP from the Milan TTP Registry (URL:http://www.ttpdatabase.org/) and 28 controls. The associations between ADAMTS13-specific CIC levels and ADAMTS13 activity, antigen, anti-ADAMTS13 IgGs and acute TTP clinical features were assessed by multivariate linear regression. RESULTS: Intra- and inter-assay coefficients of variation of the new test were 5.3 and 9.6%. In 36 patients with severe ADAMTS13 deficiency and anti-ADAMTS13 autoantibodies, the prevalence of ADAMTS13-specific CICs was 47% (n = 17; 95% confidence interval [CI], 32-63%). ADAMTS13-specific CICs were detected also in seven of 19 (37%; 95% CI, 19-59%) patients with reduced ADAMTS13 activity, but apparently negative anti-ADAMTS13 autoantibodies. ADAMTS13-specific CICs were not associated with ADAMTS13 activity, antigen or anti-ADAMTS13 IgGs. In patients with acute TTP, increasing levels of ADAMTS13-specific CICs were associated with a higher number of plasma-exchange procedures required to attain remission (per 0.1 increase in normalized OD values, beta, 2.9; 95% CI, -0.7 to 6.5). CONCLUSIONS: Approximately one to two-thirds of patients with autoimmune TTP display ADAMTS13-specific CICs. A thorough investigation of the prognostic relevance of ADAMTS13-specific CIC levels in autoimmune TTP is warranted.
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Proteínas ADAM/sangre , Complejo Antígeno-Anticuerpo/sangre , Enfermedades Autoinmunes/sangre , Púrpura Trombocitopénica Trombótica/sangre , Proteínas ADAM/inmunología , Proteína ADAMTS13 , Adulto , Enfermedades Autoinmunes/inmunología , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Prevalencia , Pronóstico , Sistema de Registros , Reproducibilidad de los Resultados , Factor de von Willebrand/metabolismoRESUMEN
BACKGROUND AND PURPOSE: Sympathetic nervous system (SNS) hyperactivity is characteristic of chronic heart failure (HF) and significantly worsens prognosis. The success of ß-adrenoceptor antagonist (ß-blockers) therapy in HF is primarily attributed to protection of the heart from the noxious effects of augmented catecholamine levels. ß-Blockers have been shown to reduce SNS hyperactivity in HF, but the underlying molecular mechanisms are not understood. The GPCR kinase-2 (GRK2)-α(2) adrenoceptor-catecholamine production axis is up-regulated in the adrenal medulla during HF causing α(2) -adrenoceptor dysfunction and elevated catecholamine levels. Here, we sought to investigate if ß-blocker treatment in HF could lower SNS activation by directly altering adrenal GRK2 levels. EXPERIMENTAL APPROACH: Four weeks after myocardial infarction-induced HF, adult rats were randomized to 10-week treatment with vehicle (HF/C) or bisoprolol (HF/B). Cardiac function and dimensions were measured. In heart and adrenal gland, GRK2 levels were assessed by RT-PCR and Western blotting and adrenoceptors studied with radioligand binding. Catecholamines and α(2) adrenoceptors in adrenal medulla chromaffin cell cultures were also measured. KEY RESULTS: Bisoprolol treatment ameliorated HF-related adverse cardiac remodelling and reduced plasma catecholamine levels, compared with HF/C rats. Bisoprolol also attenuated adrenal GRK2 overexpression as observed in HF/C rats and increased α(2) adrenoceptor density. In cultures of adrenal medulla chromaffin cells from all study groups, bisoprolol reversed HF-related α(2) adrenoceptor dysfunction. This effect was reversed by GRK2 overexpression. CONCLUSION AND IMPLICATIONS: Blockade of ß-adrenoceptors normalized the adrenal α(2) adrenoceptor-catecholamine production axis by reducing GRK2 levels. This effect may contribute significantly to the decrease of HF-related sympathetic overdrive by ß-blockers.
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Antagonistas Adrenérgicos beta/farmacología , Bisoprolol/farmacología , Catecolaminas/metabolismo , Quinasa 2 del Receptor Acoplado a Proteína-G/metabolismo , Insuficiencia Cardíaca/metabolismo , Receptores Adrenérgicos alfa 2/metabolismo , Glándulas Suprarrenales/citología , Antagonistas de Receptores Adrenérgicos beta 1/administración & dosificación , Antagonistas de Receptores Adrenérgicos beta 1/farmacología , Animales , Bisoprolol/administración & dosificación , Células Cultivadas , Células Cromafines/citología , Células Cromafines/efectos de los fármacos , Masculino , Ratas , Ratas Sprague-Dawley , Receptores Adrenérgicos alfa 2/genéticaRESUMEN
Patients with B-chronic lymphocytic leukemia present diverse clinical features, genetic abnormalities, variable response to treatment, and heterogeneous prognosis. Novel biological markers such as IgVH mutation, CD38, and ZAP-70 expression have shown to offer important prognostic information. An altered expression of the multidrug resistance 1 may represent an additional prognostic marker. Aim of our study was to evaluate two MDR-1 gene polymorphisms: G2677T polymorphism in exon 21 and C3435T polymorphism in exon 26, to evidence if polymorphisms influence the risk of development of B-CLL and whether genomic polymorphisms provide prognostic information on the clinical progression of the disease. A total of 125 patients with B-CLL and 125 healthy subjects were enrolled in this study. The mutant homozygous 2677 TT genotype was found to be associated with the occurrence of B-CLL and higher T allele frequency in patients with B-CLL when compared with controls was observed (P=0.009). When comparing the prognostic patients' characteristics, patients with 2677 GT genotype were statistically linked to the unmutated IgVH genes (r=0.209, P=0.01). Moreover, the same genotype was correlated with lymphocyte number (r=0.269, P=0.02). Finally for the 2677GT polymorphism, the heterozygous status was associated with higher hemoglobin levels (r=0.247, P=0.005). As far the C3435T MDR1 polymorphism, we were not able to identify any significant correlation with IgVH gene status or other variables. In conclusion, MDR1 gene polymorphism could be a factor predisposing to LLC. Moreover, our findings support the possibility of considering these genomic polymorphisms as prognostic markers in patients with B-CLL.
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Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/genética , Biomarcadores de Tumor/genética , Predisposición Genética a la Enfermedad , Leucemia Linfocítica Crónica de Células B/genética , Polimorfismo de Nucleótido Simple , Subfamilia B de Transportador de Casetes de Unión a ATP , Anciano , Separación Celular , Femenino , Citometría de Flujo , Genes de las Cadenas Pesadas de las Inmunoglobulinas , Genotipo , Humanos , Región Variable de Inmunoglobulina/genética , Leucemia Linfocítica Crónica de Células B/mortalidad , Leucemia Linfocítica Crónica de Células B/patología , Masculino , Estadificación de Neoplasias , Reacción en Cadena de la Polimerasa , PronósticoRESUMEN
Malignant hyperthermia (MH) is an autosomal dominant pharmacogenetic disorder of skeletal muscle characterized by disturbance of intracellular calcium homeostasis in the sarcoplasmic reticulum. Mutations of the ryanodine receptor 1 (RYR1) gene account for most cases, with some studies claiming up to 86% of mutations in this locus. However, RYR1 gene is large and variants are common even in the normal population. We examined 54 families with MH susceptibility and 21 diagnosed with equivocal MH. Thirty-five were selected for an anesthetic reaction, whereas the remainder for hyperCKemia. In these, we studied all 106 exons of the RYR1 gene. When no mutation was found, we also screened: sodium channel voltage-gated, type IV alpha subunit (SCN4A), calcium channel voltage-dependent, L type, alpha 1S subunit (CACNA1S), and L-type voltage-gated calcium channel alpha 2/delta-subunit (CACNL2A). Twenty-nine different RYR1 mutations were discovered in 40 families. Three other MH genes were tested in negative cases. Fourteen RYR1 amino acid changes were novel, of which 12 were located outside the mutational 'hot spots'. In two families, the known mutation p.R3903Q was also observed in malignant hyperthermia-nonsusceptible (MHN) individuals. Unexpectedly, four changes were also found in the same family and two in another. Our study confirms that MH is genetically heterogeneous and that a consistent number of cases are not due to RYR1 mutations. The discordance between in vitro contracture test status and the presence of a proven causative RYR1 mutation suggests that the penetrance may vary due to as yet unknown factors.
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Hipertermia Maligna/genética , Mutación Missense/genética , Canal Liberador de Calcio Receptor de Rianodina/genética , Canales de Calcio/genética , Canales de Calcio Tipo L , Familia , Haplotipos , Humanos , Canal de Sodio Activado por Voltaje NAV1.4 , Linaje , Canales de Sodio/genéticaRESUMEN
The clinical course of CLL is highly variable, and survival from the time of diagnosis of CLL can range from months to decades. Novel biological markers such as IgVH mutation, CD38, and ZAP-70 expression have shown to offer important prognostic informations. Few reports deal with the sCD138 levels and bad prognostic factors in patients with CLL, and contrasting data are reported in literature. In our study, we evaluated the serum level of sCD138 in patients with B-CLL and its relationship with other prognostic markers. There was a significant association between advanced Rai stage and serum sCD138 levels in CLL subjects. Patients with Rai stage III-IV had significantly higher levels of sCD138 with respect to controls (48.85±34 ng/ml vs. 31.1±19.34 ng/ml; P<0.05). We were unable to demonstrate a significant association between sCD138 serum levels and IgVH gene status, ZAP-70 expression, CD38 expression, beta-2 microglobulin, absolute peripheral blood lymphocytosis, haemoglobin or LDH levels. Our finding that high sCD138 serum levels correlates with advanced stages in patients with B-CLL is consistent with the possibility molecule can identify patients with high tumour burden, but the lack of correlation between sCD138 serum levels and markers such the mutation status of IgVH, ZAP-70, and CD38 suggests that sCD138 levels only reflect the clinical stage of disease than the clinical course or progression.
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ADP-Ribosil Ciclasa 1/sangre , Biomarcadores de Tumor/metabolismo , Leucemia Linfocítica Crónica de Células B/metabolismo , Anciano , Anciano de 80 o más Años , Progresión de la Enfermedad , Femenino , Humanos , Técnicas para Inmunoenzimas , Región Variable de Inmunoglobulina/genética , Leucemia Linfocítica Crónica de Células B/genética , Leucemia Linfocítica Crónica de Células B/patología , Masculino , Persona de Mediana Edad , Mutación/genética , Pronóstico , ARN Mensajero/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Tasa de Supervivencia , Proteína Tirosina Quinasa ZAP-70/metabolismoRESUMEN
Polychlorinated biphenyls (PCBs) are structurally related to dioxins, widely used in the past in various industrial applications and daily used products. Although PCBs production was discontinued more than twenty years ago, their chemical stability and high lipophilicity make them persistent pollutants and dangerous occupational contaminants. Skeletal muscle is an important site of PCB accumulation. Our previous results about the effects of PCBs on L6C5 myoblasts, showed that "low concentrations" (< 10 microg/ml) of these compounds inhibit in vitro myogenic differentiation in a concentration-dependent fashion, while toxic effects only begin to be evident at PCB concentrations > or = 10 microg/ml. In the present paper we wondered if the observed cell mortality is due to necrosis or if it depends on the activation of programmed cell death mechanisms (apoptosis). Using different methods of analysis, we have observed that PCBs cause necrosis of myogenic cells and that such effect is related to the employed concentrations and to the time of exposure (EC50 approximately = 50 microg/ml). Our results may help to explain the creatin kinase elevation, observed in the blood of patients acutely exposed to high concentrations of PCBs, as the consequence of a necrotic damage of the skeletal muscle. It will be therefore interesting to evaluate the presence of muscular damages in the chronic exposures to PCBs.
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Contaminantes Ambientales/toxicidad , Mioblastos/efectos de los fármacos , Bifenilos Policlorados/toxicidad , Animales , Apoptosis , Línea Celular , Creatina Quinasa/sangre , Citofotometría , Citoplasma/enzimología , Interpretación Estadística de Datos , Contaminantes Ambientales/administración & dosificación , Humanos , L-Lactato Deshidrogenasa/análisis , Mioblastos/patología , Necrosis/inducido químicamente , Necrosis/enzimología , Bifenilos Policlorados/administración & dosificación , RatasRESUMEN
Polychlorinated biphenyls (PCBs) are ubiquitous and persistent pollutants whose role in developmental toxicity is of great concern. The observation that the offspring of PCB-exposed mothers (both in humans and rodents) display reduced body mass prompted us to investigate the effects of commercial mixtures of PCB congeners (Aroclor 1232, 1254, and 1262) on differentiation of both a myogenic cell line and primary myogenic cell cultures. The fusion of L6 myoblasts into multinucleated myotubes and the increase of creatine kinase (CK) activity were dose-dependently inhibited by Aroclor 1254 at concentrations (0.1-4 microg/ml) that caused no effect on cell density. Ultrastructural analysis demonstrated that Aroclor 1254 also prevented the accumulation of contractile filaments while inducing hypertrophy of the smooth endoplasmic reticulum and appearance of membrane-filled autophagosomes. Half-maximal inhibition (IC50) of CK activity accumulation occurred at 0.01 microg/ml for Aroclor 1262, 2 microg/ml for Aroclor 1254, and 8 microg/ml for Aroclor 1232. Aroclor-dependent inhibition of myogenic differentiation was also shown by the reduced expression and nuclear accumulation of beta-galactosidase in primary cultures of fetal myoblasts from transgenic mice expressing this reporter gene under the control of the myosin light chain promoter. These data show that skeletal muscle differentiation is specifically impaired by PCBs and may explain the reported depression of body mass growth in PCB-exposed offspring at birth. Furthermore, myogenic cell cultures are highly sensitive to PCBs and allow the detection of biological effects of environmental levels of these pollutants.
Asunto(s)
Arocloros/toxicidad , Diferenciación Celular/efectos de los fármacos , Contaminantes Ambientales/toxicidad , Músculo Esquelético/efectos de los fármacos , Citoesqueleto de Actina/efectos de los fármacos , Citoesqueleto de Actina/ultraestructura , Animales , Línea Celular , Núcleo Celular/efectos de los fármacos , Núcleo Celular/enzimología , Creatina Quinasa/antagonistas & inhibidores , Creatina Quinasa/metabolismo , ADN/biosíntesis , Relación Dosis-Respuesta a Droga , Retículo Endoplásmico Liso/efectos de los fármacos , Retículo Endoplásmico Liso/ultraestructura , Insulina/farmacología , Ratones , Ratones Transgénicos , Músculo Esquelético/citología , Músculo Esquelético/enzimología , Fagosomas/efectos de los fármacos , Fagosomas/ultraestructura , Ratas , Vasopresinas/farmacología , beta-Galactosidasa/genética , beta-Galactosidasa/metabolismoRESUMEN
The Authors have evaluated the hypophysis gonadotropic reserve after stimulation by synthetic GnRH (100 ng) in women affected by functional hyperprolactinemia and by prolactin-secreting adenoma. The LH response was significatively higher in women affected by functional hyperprolactinemia. The PRL values seem to have no influence on the gonadotropic reserve except for the cases in which The PRL levels were higher than 200 ng/ml. In all these cases a prolactinoma was present. The FSH response was similar in the two groups considered.