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1.
Cancers (Basel) ; 13(9)2021 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-34063684

RESUMEN

Hepatic resection has been widely accepted as the first choice for the treatment of colorectal metastases. Liver surgery has been recognized as a major abdominal procedure; it exposes patients to a high risk of perioperative adverse events. Decision sharing and the multimodal approach to the patients' management are the two key items for a safe outcome, even in such a high-risk surgery. This review aims at addressing the main perioperative issues (preoperative evaluation; general anesthesia and intraoperative fluid management and hemodynamic monitoring; intraoperative metabolism; administration policy for blood-derivative products; postoperative pain control; postoperative complications), in particular, from the anesthetist's point of view; however, only an alliance with the surgery team may be successful in case of adverse events to accomplish a good final outcome.

2.
J Clin Monit Comput ; 35(4): 731-740, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-32430788

RESUMEN

Mortality after liver surgery reduced during the last three decades to less than 2%, but post-operative morbidity occurs in 20-50% of cases. Patients are often considered eligible for post-operative intensive-care unit (ICU) admission. Predicting which patients that are at higher risk could lead to a more precise perioperative management. We investigated whether renal resistive index (RRI), alone or along with other items, can predict post-operative complication after hepatic resection. All consecutive patients undergoing hepatectomy for primary or metastatic neoplasm at our Institution between February 2015 and March 2017 were enrolled. They received RRI measurement before entering in operative room and after awakening from general anesthesia. 183 Patients were enrolled. High surgical invasiveness, surgery time > 360 min, pre-operative RRI and postoperative serum lactate clearance < - 6%, showed to be associated with postoperative complications. Pre-operative RRI, complex liver resection, long-lasting surgery and poor lactate clearance (cLac) close to awakening from general anesthesia, all together may permit to classify the risk of post-operative adverse outcome after hepatic resection surgery.


Asunto(s)
Hepatectomía , Hígado , Hepatectomía/efectos adversos , Humanos , Unidades de Cuidados Intensivos , Complicaciones Posoperatorias
3.
Front Neurol ; 8: 394, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28855887

RESUMEN

Freezing of gait (FOG) is a disabling symptom that is common among patients with advanced Parkinson's disease (PD). External cues such as rhythmic auditory stimulation can help PD patients experiencing freezing to resume walking. Wearable systems for automatic freezing detection have been recently developed. However, these systems detect a FOG episode after it has happened. Instead, in this study, a new approach for the prediction of FOG (before it actually happens) is presented. Prediction of FOG might enable preventive cueing, reducing the likelihood that FOG will occur. Moreover, understanding the causes and circumstances of FOG is still an open research problem. Hence, a quantitative characterization of movement patterns just before FOG (the pre-FOG phase) is of great importance. In this study, wearable inertial sensors were used to identify and quantify the characteristics of gait during the pre-FOG phase and compare them with the characteristics of gait that do not precede FOG. The hypothesis of this study is based on the threshold-based model of FOG, which suggests that before FOG occurs, there is a degradation of the gait pattern. Eleven PD subjects were analyzed. Six features extracted from movement signals recorded by inertial sensors showed significant differences between gait and pre-FOG. A classification algorithm was developed in order to test if it is feasible to predict FOG (i.e., detect it before it happens). The aim of the classification procedure was to identify the pre-FOG phase. Results confirm that there is a degradation of gait occurring before freezing. Results also provide preliminary evidence on the feasibility of creating an automatic algorithm to predict FOG. Although some limitations are present, this study shows promising findings for characterizing and identifying pre-FOG patterns, another step toward a better understanding, prediction, and prevention of this disabling symptom.

4.
J Hepatobiliary Pancreat Sci ; 24(11): 627-636, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28884958

RESUMEN

BACKGROUND: Serum lactate (sLac) concentration during liver resection with intermittent hepatic hilum clamping (i.e. Pringle maneuver, PM) was retrospectively investigated. METHODS: A total of 133 patients who underwent liver resection were enrolled. We analyzed the sLac peri-operatively. Correlations were searched between the PM and lactatemia and its variations (i.e. lactate clearance, cLac) and other factors which it might be related to. Lactatemia in triplicate intraoperatively was recorded, just after the awakening, and 1 and 2 h later. The cLac between two consecutive measurements [(sLac1 - sLac2 )/sLac1 ] was computed. RESULTS: A reliable dependence of sLac was found from the cumulative PM. More than 76 min of cumulative Pringle Time (cPT) exposed patients to a worse cLac at the end of the resection phase (P < 0.0001). We found cPT >76 min, global operation time >365 min and bleeding >225 ml to be predictors of hyperlactatemia (sLac >4 mmol/L). Normal liver resulted as a risk factor for hyperlactatemia and steatosis was not (P = 0.030 vs. P = 0.325). Finally, cLac showed a "square-root- shape, just like the mathematical operation sign. CONCLUSIONS: Lactatemia during liver resection depends on the duration of PM, bleeding and the duration of the operation. Normal liver may expose the patient to the risk of hyperlactatemia.


Asunto(s)
Pérdida de Sangre Quirúrgica/prevención & control , Hepatectomía/métodos , Ácido Láctico/sangre , Neoplasias Hepáticas/sangre , Neoplasias Hepáticas/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores/sangre , Estudios de Cohortes , Constricción , Supervivencia sin Enfermedad , Femenino , Estudios de Seguimiento , Hepatectomía/mortalidad , Humanos , Neoplasias Hepáticas/mortalidad , Neoplasias Hepáticas/patología , Modelos Logísticos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Tempo Operativo , Estudios Retrospectivos , Medición de Riesgo , Análisis de Supervivencia , Resultado del Tratamiento
5.
Gait Posture ; 46: 26-9, 2016 05.
Artículo en Inglés | MEDLINE | ID: mdl-27131172

RESUMEN

Altered postural control and balance are major disabling issues of Parkinson's disease (PD). Static and dynamic posturography have provided insight into PD's postural deficits; however, little is known about impairments in postural coordination. We hypothesized that subjects with PD would show more ankle strategy during quiet stance than healthy control subjects, who would include some hip strategy, and this stiffer postural strategy would increase with disease progression. We quantified postural strategy and sway dispersion with inertial sensors (one placed on the shank and one on the posterior trunk at L5 level) while subjects were standing still with their eyes open. A total of 70 subjects with PD, including a mild group (H&Y≤2, N=33) and a more severe group (H&Y≥3, N=37), were assessed while OFF and while ON levodopa medication. We also included a healthy control group (N=21). Results showed an overall preference of ankle strategy in all groups while maintaining balance. Postural strategy was significantly lower ON compared to OFF medication (indicating more hip strategy), but no effect of disease stage was found. Instead, sway dispersion was significantly larger in ON compared to OFF medication, and significantly larger in the more severe PD group compared to the mild. In addition, increased hip strategy during stance was associated with poorer self-perception of balance.


Asunto(s)
Levodopa/uso terapéutico , Enfermedad de Parkinson/tratamiento farmacológico , Equilibrio Postural/efectos de los fármacos , Adulto , Anciano , Progresión de la Enfermedad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Enfermedad de Parkinson/complicaciones , Enfermedad de Parkinson/fisiopatología , Postura
6.
World J Surg ; 40(9): 2202-12, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27094558

RESUMEN

BACKGROUND: The Pringle maneuver, which is performed during liver surgery to reduce blood loss, may result in liver ischemia/reperfusion injury resulting in metabolic, immunological, and microvascular changes, which may lead to hepatocellular damage. The aim of this study was the investigation of the effects of N-acetylcysteine (NAC) and methylprednisolone (MET) in the modulation of liver warm ischemia during hepatic resection. METHODS: Forty-eight patients were enrolled in a pilot double-blind, randomized clinical trial. The patients received either NAC, MET, or placebo. The primary endpoint was the reduction in postoperative alanine aminotransferase and bilirubin. The secondary endpoint was the difference in morbidity and mortality. RESULTS: All the 48 patients had liver resection with no mortality. Morbidity was observed in 8 (16 %) patients equally distributed among the groups. There was a significant favorable recovery of liver function tests in patients treated with NAC or MET compared with the placebo when the Pringle maneuver exceeded 70 min. CONCLUSIONS: The administration of NAC or MET prior to the Pringle maneuver during hepatic resection is associated with lower postoperative aberration in liver function tests compared with placebo when the Pringle maneuver exceeded 70 min. Larger studies are required to validate our findings and to investigate the specific role of NAC and MET in liver surgery.


Asunto(s)
Acetilcisteína/uso terapéutico , Hepatectomía/métodos , Metilprednisolona/uso terapéutico , Daño por Reperfusión/prevención & control , Torniquetes , Adulto , Anciano , Anciano de 80 o más Años , Alanina Transaminasa/sangre , Bilirrubina/sangre , Método Doble Ciego , Femenino , Depuradores de Radicales Libres , Glucocorticoides , Humanos , Pruebas de Función Hepática , Neoplasias Hepáticas/cirugía , Masculino , Persona de Mediana Edad , Proyectos Piloto , Estudios Prospectivos , Daño por Reperfusión/etiología , Instrumentos Quirúrgicos , Adulto Joven
7.
Parkinsonism Relat Disord ; 22: 28-34, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26777408

RESUMEN

BACKGROUND: Inertial measurement units combined with a smartphone application (CuPiD-system) were developed to provide people with Parkinson's disease (PD) real-time feedback on gait performance. This study investigated the CuPiD-system's feasibility and effectiveness compared with conventional gait training when applied in the home environment. METHODS: Forty persons with PD undertook gait training for 30 min, three times per week for six weeks. Participants were randomly assigned to i) CuPiD, in which a smartphone application offered positive and corrective feedback on gait, or ii) an active control, in which personalized gait advice was provided. Gait, balance, endurance and quality of life were assessed before and after training and at four weeks follow-up using standardized tests. RESULTS: Both groups improved significantly on the primary outcomes (single and dual task gait speed) at post-test and follow-up. The CuPiD group improved significantly more on balance (MiniBESTest) at post-test (from 24.8 to 26.1, SD ∼ 5) and maintained quality of life (SF-36 physical health) at follow-up whereas the control group deteriorated (from 50.4 to 48.3, SD ∼ 16). No other statistically significant differences were found between the two groups. The CuPiD system was well-tolerated and participants found the tool user-friendly. CONCLUSION: CuPiD was feasible, well-accepted and seemed to be an effective approach to promote gait training, as participants improved equally to controls. This benefit may be ascribed to the real-time feedback, stimulating corrective actions and promoting self-efficacy to achieve optimal performance. Further optimization of the system and adequately-powered studies are warranted to corroborate these findings and determine cost-effectiveness.


Asunto(s)
Retroalimentación Formativa , Trastornos Neurológicos de la Marcha/rehabilitación , Aplicaciones Móviles , Enfermedad de Parkinson/rehabilitación , Teléfono Inteligente , Anciano , Estudios de Factibilidad , Femenino , Estado de Salud , Humanos , Masculino , Persona de Mediana Edad , Resistencia Física , Modalidades de Fisioterapia , Proyectos Piloto , Equilibrio Postural , Calidad de Vida , Resultado del Tratamiento
8.
IEEE Trans Neural Syst Rehabil Eng ; 24(7): 764-73, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-26259246

RESUMEN

Gait impairments are among the most disabling symptoms in several musculoskeletal and neurological conditions, severely limiting personal autonomy. Wearable gait sensors have been attracting attention as diagnostic tool for gait and are emerging as promising tool for tutoring and guiding gait execution. If their popularity is continuously growing, still there is room for improvement, especially towards more accurate solutions for spatio-temporal gait parameters estimation. We present an implementation of a zero-velocity-update gait analysis system based on a Kalman filter and off-the-shelf shoe-worn inertial sensors. The algorithms for gait events and step length estimation were specifically designed to comply with pathological gait patterns. More so, an Android app was deployed to support fully wearable and stand-alone real-time gait analysis. Twelve healthy subjects were enrolled to preliminarily tune the algorithms; afterwards sixteen persons with Parkinson's disease were enrolled for a validation study. Over the 1314 strides collected on patients at three different speeds, the total root mean square difference on step length estimation between this system and a gold standard was 2.9%. This shows that the proposed method allows for an accurate gait analysis and paves the way to a new generation of mobile devices usable anywhere for monitoring and intervention.


Asunto(s)
Algoritmos , Trastornos Neurológicos de la Marcha/fisiopatología , Marcha , Pierna/fisiopatología , Monitoreo Ambulatorio/métodos , Análisis Espacio-Temporal , Adulto , Anciano , Simulación por Computador , Sistemas de Computación , Femenino , Trastornos Neurológicos de la Marcha/diagnóstico , Humanos , Masculino , Persona de Mediana Edad , Modelos Estadísticos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Procesamiento de Señales Asistido por Computador
9.
J Cell Mol Med ; 19(9): 2098-107, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26010680

RESUMEN

Gynaecological leiomyosarcoma (gLMS) represent a heterogeneous group of soft tissue sarcoma, characterized by rare incidence, high aggressiveness and propensity to infiltrate secondary organs, poor prognosis and lethality, because of the lack of biological mechanisms that underlying their progression and effective pharmaceutical treatments. This study was focused on some of the aspects of progression and dissemination of a subtype of gLMS namely vulvar LMS (vLMS). We therefore used a vulvar LMS-derived cell line namely SK-LMS-1, coupled with in vitro and in vivo assays. We observed that SK-LMS-1 cells have a strong invasive capacity in vitro, through the activity of matrix metalloproteinases 2 and 9, while in vivo these cells induce a strong angiogenic response and disseminate to the chick embryo liver. Therefore, we postulate that metalloproteinases are involved in the spreading behaviour of SK-LMS-1. Further investigations are necessary to better understand the molecular and cellular machinery involved in the progression of this malignancy.


Asunto(s)
Leiomiosarcoma/irrigación sanguínea , Leiomiosarcoma/enzimología , Metaloproteinasas de la Matriz/metabolismo , Neovascularización Patológica/enzimología , Neoplasias de la Vulva/irrigación sanguínea , Neoplasias de la Vulva/enzimología , Inductores de la Angiogénesis/metabolismo , Animales , Línea Celular Tumoral , Pollos , Membrana Corioalantoides/metabolismo , Colágeno/metabolismo , Combinación de Medicamentos , Activación Enzimática , Femenino , Humanos , Laminina/metabolismo , Leiomiosarcoma/patología , Invasividad Neoplásica , Metástasis de la Neoplasia , Proteoglicanos/metabolismo , Neoplasias de la Vulva/patología
10.
FASEB J ; 29(8): 3472-82, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25934701

RESUMEN

Dyskerin is a pseudouridine (ψ) synthase involved in fundamental cellular processes including uridine modification in rRNA and small nuclear RNA and telomere stabilization. Dyskerin functions are altered in X-linked dyskeratosis congenita (X-DC) and cancer. Dyskerin's role in rRNA pseudouridylation has been suggested to underlie the alterations in mRNA translation described in cells lacking dyskerin function, although relevant direct evidences are currently lacking. Our purpose was to establish definitely whether defective dyskerin function might determine an intrinsic ribosomal defect leading to an altered synthetic activity. Therefore, ribosomes from dyskerin-depleted human cells were purified and 1) added to a controlled reticulocyte cell-free system devoid of ribosomes to study mRNA translation; 2) analyzed for protein contamination and composition by mass spectrometry, 3) analyzed for global pseudouridylation levels. Ribosomes purified from dyskerin-depleted cells showed altered translational fidelity and internal ribosome entry site (IRES)-mediated translation. These ribosomes displayed reduced uridine modification, whereas they were not different in terms of protein contamination or ribosomal protein composition with respect to ribosomes from matched control cells with full dyskerin activity. In conclusion, lack of dyskerin function in human cells induces a defect in rRNA uridine modification, which is sufficient to alter ribosome activity.


Asunto(s)
Proteínas de Ciclo Celular/metabolismo , Proteínas Nucleares/metabolismo , Biosíntesis de Proteínas/genética , Ribosomas/metabolismo , Proteínas de Ciclo Celular/genética , Línea Celular Tumoral , Sistema Libre de Células/metabolismo , Humanos , Células MCF-7 , Proteínas Nucleares/genética , ARN Mensajero/genética , ARN Ribosómico/genética , Ribosomas/genética , Telómero/genética , Telómero/metabolismo
11.
Histopathology ; 66(2): 244-51, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25367684

RESUMEN

AIMS: To investigate the immunohistochemical expression of dyskerin, a biomarker involved in ribosome production and telomere maintenance, in human fetal, adult and neoplastic bile ducts, and possible correlations with cholangiocarcinoma aggressiveness. METHODS AND RESULTS: Sixty consecutive intrahepatic cholangiocarcinomas were collected and used for tissue microarray construction (total: 176 cores); clinical data and follow-up were also collected. Five fetal and 10 normal adult livers were included as controls. Automated immunohistochemistry for dyskerin, p53, and Ki67, and nucleolar silver staining, were performed. In normal livers, dyskerin expression was negative in smaller bile ducts (mean 44.8 µm) and positive in bile ducts of larger diameter (mean 116.1 µm; P < 0.001). Expression was positive in 56.7% of cholangiocarcinomas, and correlated with p53 mutation (P = 0.008) and a higher proliferative (Ki67) index (P = 0.003), which were included as markers of tumour aggressiveness. Finally, dyskerin-positive cholangiocarcinomas showed a negative trend in disease-free survival (P = 0.078) on univariate analysis. CONCLUSIONS: The non-neoplastic biliary tree seems to progressively lose dyskerin expression from the major branches to the peripheral portal bile ducts. Similarly, intrahepatic cholangiocarcinomas showed two patterns of dyskerin expression, and the dyskerin-positive phenotype seemed to characterize more aggressive cholangiocarcinomas.


Asunto(s)
Neoplasias de los Conductos Biliares/patología , Conductos Biliares Intrahepáticos/patología , Biomarcadores de Tumor/análisis , Proteínas de Ciclo Celular/biosíntesis , Colangiocarcinoma/patología , Proteínas Nucleares/biosíntesis , Adulto , Anciano , Neoplasias de los Conductos Biliares/metabolismo , Neoplasias de los Conductos Biliares/mortalidad , Conductos Biliares Intrahepáticos/embriología , Conductos Biliares Intrahepáticos/metabolismo , Proteínas de Ciclo Celular/análisis , Colangiocarcinoma/metabolismo , Colangiocarcinoma/mortalidad , Supervivencia sin Enfermedad , Femenino , Feto , Humanos , Inmunohistoquímica , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Proteínas Nucleares/análisis , Modelos de Riesgos Proporcionales , Análisis de Matrices Tisulares
12.
Histol Histopathol ; 30(1): 69-76, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25046102

RESUMEN

The role of angiogenesis as a hallmark of tumor progression has been poorly explored in leiomyosarcoma, a rare but aggressive mesenchymal malignancy. We aimed to characterize microvessel distribution and morphology - including pericyte coverage - in a retrospective series of leyomiosarcomas of the soft tissues and the uterus. 41 whole-block tumor slides from formalin-fixed paraffin-embedded tissues were immunostained for endothelial-specific marker CD31 and microvessel density was quantified by assigning a grade to the frequency of CD31 positive microvessels. Vessel morphology and pericyte coverage were investigated by double-labeling for CD31 and either PDGFRß, αSMA, desmin, CD90, or CD146. We found that microvessel density correlated with tumor grade in leiomyosarcoma of soft tissues, in analogy with what has been established in several types of carcinoma. This did not apply to uterine leiomyosarcoma, possibly due to the abundant myometrial vascularization. The evaluation of perivascular cell markers related to vessel stability revealed immature microvascular networks with aberrant pericyte coverage, irrespective of tumor origin or grade. Our observations substantiate the role of angiogenesis in the progression of soft tissue leiomyosarcoma. A multiple-marker approach to the assessment of pericyte coverage can identify different profiles of vessel immaturity correlated with tumor grade.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Leiomiosarcoma/metabolismo , Neovascularización Patológica/metabolismo , Neoplasias de los Tejidos Blandos/metabolismo , Neoplasias Uterinas/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Antígenos CD/metabolismo , Femenino , Humanos , Masculino , Microcirculación , Persona de Mediana Edad , Neovascularización Patológica/patología , Pericitos/metabolismo , Pericitos/patología , Pronóstico , Estudios Retrospectivos , Neoplasias de los Tejidos Blandos/patología , Neoplasias Uterinas/patología
13.
Biosci Rep ; 34(6): e00147, 2014 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-25236925

RESUMEN

STS (soft tissue sarcomas) are rare malignant tumours deriving from cells of mesenchymal origin and represent only 1% of all malignant neoplasms. It has been extensively demonstrated that angiogenesis has an important role in cancer malignancy. Particularly, a lot of studies demonstrate the importance of angiogenesis in the development of carcinomas, whereas little is known about the role of angiogenesis in sarcomas and especially in STS. This review aims at summarizing the new discoveries about the nature and the importance of angiogenesis in STS and the new possible therapeutic strategies involved. Only a few studies concerning STS focus on tumour neovascularization and proangiogenic factors and look for a correlation with the patients prognosis/survival. These studies demonstrate that intratumoural MVD (microvessels density) may not accurately represent the angiogenic capacity of STS. Nevertheless, this does not exclude the possibility that angiogenesis could be important in STS. The importance of neoangiogenesis in soft tissue tumours is confirmed by the arising number of publications comparing angiogenesis mediators with clinical features of patients with STS. The efficacy of anti-angiogenic therapies in other types of cancer is well documented. The understanding of the involvement of the angiogenic process in STS, together with the necessity to improve the therapy for this often mortal condition, prompted the exploration of anti-tumour compounds targeting this pathway. In conclusion, this review emphasizes the importance to better understand the mechanisms of angiogenesis in STS in order to subsequently design-specific target therapies for this group of poorly responding tumours.


Asunto(s)
Inhibidores de la Angiogénesis/uso terapéutico , Antineoplásicos/uso terapéutico , Neovascularización Patológica/prevención & control , Sarcoma/irrigación sanguínea , Sarcoma/tratamiento farmacológico , Factor 2 de Crecimiento de Fibroblastos/antagonistas & inhibidores , Factor 2 de Crecimiento de Fibroblastos/metabolismo , Humanos , Metaloproteinasas de la Matriz/metabolismo , Modelos Biológicos , Neovascularización Patológica/metabolismo , Factor de Crecimiento Placentario , Proteínas Gestacionales/antagonistas & inhibidores , Proteínas Gestacionales/metabolismo , Sarcoma/metabolismo , Factor A de Crecimiento Endotelial Vascular/antagonistas & inhibidores , Factor A de Crecimiento Endotelial Vascular/metabolismo
14.
PLoS One ; 9(7): e101971, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25010840

RESUMEN

The product of the DKC1 gene, dyskerin, is required for both ribosome biogenesis and telomerase complex stabilization. Targeting these cellular processes has been explored for the development of drugs to selectively or preferentially kill cancer cells. Presently, intense research is conducted involving the identification of new biological targets whose modulation may simultaneously interfere with multiple cellular functions that are known to be hyper-activated by neoplastic transformations. Here, we report, for the first time, the computational identification of small molecules able to inhibit dyskerin catalytic activity. Different in silico techniques were applied to select compounds and analyze the binding modes and the interaction patterns of ligands in the human dyskerin catalytic site. We also describe a newly developed and optimized fast real-time PCR assay that was used to detect dyskerin pseudouridylation activity in vitro. The identification of new dyskerin inhibitors constitutes the first proof of principle that the pseudouridylation activity can be modulated by means of small molecule agents. Therefore, the presented results, obtained through the usage of computational tools and experimental validation, indicate an alternative therapeutic strategy to target ribosome biogenesis pathway.


Asunto(s)
Proteínas de Ciclo Celular/antagonistas & inhibidores , Proteínas Nucleares/antagonistas & inhibidores , Ribosomas/efectos de los fármacos , Ribosomas/metabolismo , Bibliotecas de Moléculas Pequeñas/farmacología , Secuencia de Bases , Biocatálisis , Proteínas de Ciclo Celular/química , Proteínas de Ciclo Celular/metabolismo , Diseño de Fármacos , Humanos , Modelos Moleculares , Proteínas Nucleares/química , Proteínas Nucleares/metabolismo , Conformación Proteica , Seudouridina/metabolismo , ARN Ribosómico/genética , ARN Ribosómico/metabolismo , Relación Estructura-Actividad
15.
Sensors (Basel) ; 14(4): 6229-46, 2014 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-24686731

RESUMEN

In this paper, a system for gait training and rehabilitation for Parkinson's disease (PD) patients in a daily life setting is presented. It is based on a wearable architecture aimed at the provision of real-time auditory feedback. Recent studies have, in fact, shown that PD patients can receive benefit from a motor therapy based on auditory cueing and feedback, as happens in traditional rehabilitation contexts with verbal instructions given by clinical operators. To this extent, a system based on a wireless body sensor network and a smartphone has been developed. The system enables real-time extraction of gait spatio-temporal features and their comparison with a patient's reference walking parameters captured in the lab under clinical operator supervision. Feedback is returned to the user in form of vocal messages, encouraging the user to keep her/his walking behavior or to correct it. This paper describes the overall concept, the proposed usage scenario and the parameters estimated for the gait analysis. It also presents, in detail, the hardware-software architecture of the system and the evaluation of system reliability by testing it on a few subjects.


Asunto(s)
Marcha , Enfermedad de Parkinson/fisiopatología , Enfermedad de Parkinson/rehabilitación , Telemetría/instrumentación , Algoritmos , Calibración , Sistemas de Computación , Retroalimentación , Humanos , Masculino , Termodinámica
16.
IEEE Trans Neural Syst Rehabil Eng ; 22(5): 1064-71, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24760912

RESUMEN

In this study, the use of an instrumented balance test based on inertial sensors was evaluated in patients with Parkinson's disease (PD). We aimed to objectively characterize motor subtypes of PD [tremor dominant (TD) and postural instability gait difficulty (PIGD)], to help to quantitatively classify the PD subjects into motor subtypes. Subjects were studied performing postural tests, while wearing a device including a tri-axial accelerometer on the lower back, in four different experimental conditions that depended on feet position (feet-together or semi-tandem) and vision (eyes open or closed). Postural measures, after a reliability check, were tested to identify their sensitivity to the disease, to the PD subtypes, and to the experimental conditions. The results highlight the possibility of distinguishing between the TD and PIGD subtypes by means of objective postural measures that are able to detect tremor and PIGD features and are able to classify a subject as TD or PIGD with good accuracy. Feet position influences frequency measures, whereas eyes closure influences the displacement measures and enhances differences between PD and control subjects, suggesting that postural displacement measures may be capable of detecting different adaptation processes to external sensory conditions between patients with PD and control subjects.


Asunto(s)
Monitoreo Fisiológico/métodos , Enfermedad de Parkinson/diagnóstico , Enfermedad de Parkinson/fisiopatología , Equilibrio Postural , Anciano , Anciano de 80 o más Años , Análisis Discriminante , Femenino , Humanos , Masculino , Persona de Mediana Edad , Monitoreo Fisiológico/instrumentación , Movimiento , Enfermedad de Parkinson/clasificación , Reproducibilidad de los Resultados , Temblor/fisiopatología
17.
Gait Posture ; 40(1): 70-5, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24656713

RESUMEN

UNLABELLED: The present study introduces a novel instrumented method to characterize postural movement strategies to maintain balance during stance (ankle and hip strategy), by means of inertial sensors, positioned on the legs and on the trunk. We evaluated postural strategies in subjects with 2 types of Parkinsonism: idiopathic Parkinson's disease (PD) and Progressive Supranuclear Palsy (PSP), and in age-matched control subjects standing under perturbed conditions implemented by the Sensory Organization Test (SOT). Coordination between the upper and lower segments of the body during postural sway was measured using a covariance index over time, by a sliding-window algorithm. Afterwards, a postural strategy index was computed. We also measured the amount of postural sway, as adjunctive information to characterize balance, by the root mean square of the horizontal trunk acceleration signal (RMS). RESULTS: showed that control subjects were able to change their postural strategy, whilst PSP and PD subjects persisted in use of an ankle strategy in all conditions. PD subjects had RMS values similar to control subjects even without changing postural strategy appropriately, whereas PSP subjects showed much larger RMS values than controls, resulting in several falls during the most challenging SOT conditions (5 and 6). Results are in accordance with the corresponding clinical literature describing postural behavior in the same kind of subjects. The proposed strategy index, based on the use of inertial sensors on the upper and lower body segments, is a promising and unobtrusive tool to characterize postural strategies performed to attain balance.


Asunto(s)
Ataxia/diagnóstico , Ataxia/fisiopatología , Enfermedad de Parkinson/fisiopatología , Equilibrio Postural/fisiología , Trastornos de la Sensación/diagnóstico , Trastornos de la Sensación/fisiopatología , Parálisis Supranuclear Progresiva/fisiopatología , Aceleración , Acelerometría/instrumentación , Anciano , Tobillo/fisiopatología , Ataxia/etiología , Retroalimentación Sensorial/fisiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Modelos Biológicos , Monitoreo Fisiológico/instrumentación , Movimiento/fisiología , Enfermedad de Parkinson/complicaciones , Trastornos de la Sensación/etiología , Parálisis Supranuclear Progresiva/complicaciones , Torso/fisiopatología
18.
Nucleic Acids Res ; 41(17): 8308-18, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23821664

RESUMEN

Dyskerin is a nucleolar protein encoded by the DKC1 gene that (i) stabilizes the RNA component of the telomerase complex, and (ii) drives the site-specific pseudouridilation of rRNA. It is known that the partial lack of dyskerin function causes a defect in the translation of a subgroup of mRNAs containing internal ribosome entry site (IRES) elements such as those encoding for the tumor suppressors p27 and p53. In this study, we aimed to analyze what is the effect of the lack of dyskerin on the IRES-mediated translation of mRNAs encoding for vascular endothelial growth factor (VEGF). We transiently reduced dyskerin expression and measured the levels of the IRES-mediated translation of the mRNA encoding for VEGF in vitro in transformed and primary cells. We demonstrated a significant increase in the VEGF IRES-mediated translation after dyskerin knock-down. This translational modulation induces an increase in VEGF production in the absence of a significant upregulation in VEGF mRNA levels. The analysis of a list of viral and cellular IRESs indicated that dyskerin depletion can differentially affect IRES-mediated translation. These results indicate for the first time that dyskerin inhibition can upregulate the IRES translation initiation of specific mRNAs.


Asunto(s)
Regiones no Traducidas 5' , Proteínas de Ciclo Celular/fisiología , Proteínas Nucleares/fisiología , Iniciación de la Cadena Peptídica Traduccional , Factor A de Crecimiento Endotelial Vascular/genética , Proteínas de Ciclo Celular/antagonistas & inhibidores , Proteínas de Ciclo Celular/genética , Línea Celular Tumoral , Técnicas de Silenciamiento del Gen , Humanos , Proteínas Nucleares/antagonistas & inhibidores , Proteínas Nucleares/genética , Interferencia de ARN , ARN Mensajero/química , ARN Viral/química , Regulación hacia Arriba , Factor A de Crecimiento Endotelial Vascular/biosíntesis
19.
J Natl Cancer Inst ; 105(7): 489-98, 2013 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-23486551

RESUMEN

BACKGROUND: The metabolic alterations of cancer cells represent an opportunity for developing selective antineoplastic treatments. We investigated the therapeutic potential of ST1326, an inhibitor of carnitine-palmitoyl transferase 1A (CPT1A), the rate-limiting enzyme for fatty acid (FA) import into mitochondria. METHODS: ST1326 was tested on in vitro and in vivo models of Burkitt's lymphoma, in which c-myc, which drives cellular demand for FA metabolism, is highly overexpressed. We performed assays to evaluate the effect of ST1326 on proliferation, FA oxidation, and FA mitochondrial channeling in Raji cells. The therapeutic efficacy of ST1326 was tested by treating Eµ-myc mice (control: n = 29; treatment: n = 24 per group), an established model of c-myc-mediated lymphomagenesis. Experiments were performed on spleen-derived c-myc-overexpressing B cells to clarify the role of c-myc in conferring sensitivity to ST1326. Survival was evaluated with Kaplan-Meier analyses. All statistical tests were two-sided. RESULTS: ST1326 blocked both long- and short-chain FA oxidation and showed a strong cytotoxic effect on Burkitt's lymphoma cells (on Raji cells at 72 hours: half maximal inhibitory concentration = 8.6 µM). ST1326 treatment induced massive cytoplasmic lipid accumulation, impairment of proper mitochondrial FA channeling, and reduced availability of cytosolic acetyl coenzyme A, a fundamental substrate for de novo lipogenesis. Moreover, treatment with ST1326 in Eµ-myc transgenic mice prevented tumor formation (P = .01), by selectively impairing the growth of spleen-derived primary B cells overexpressing c-myc (wild-type cells + ST1326 vs. Eµ-myc cells + ST1326: 99.75% vs. 57.5%, difference = 42.25, 95% confidence interval of difference = 14% to 70%; P = .01). CONCLUSIONS: Our data indicate that it is possible to tackle c-myc-driven tumorigenesis by altering lipid metabolism and exploiting the neoplastic cell addiction to FA oxidation.


Asunto(s)
Anticarcinógenos/farmacología , Apoptosis/efectos de los fármacos , Linfoma de Burkitt/enzimología , Linfoma de Burkitt/prevención & control , Carnitina O-Palmitoiltransferasa/antagonistas & inhibidores , Carnitina O-Palmitoiltransferasa/metabolismo , Carnitina/análogos & derivados , Metabolismo de los Lípidos/efectos de los fármacos , Proteínas Proto-Oncogénicas c-myc/metabolismo , Animales , Linfocitos B/efectos de los fármacos , Linfocitos B/metabolismo , Western Blotting , Linfoma de Burkitt/metabolismo , Linfoma de Burkitt/patología , Carnitina/farmacología , Carnitina Aciltransferasas/antagonistas & inhibidores , Carnitina Aciltransferasas/metabolismo , Línea Celular Tumoral , Ácidos Grasos/metabolismo , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Estimación de Kaplan-Meier , Ratones , Oxidación-Reducción , Proteínas Proto-Oncogénicas c-myc/efectos de los fármacos , Reacción en Cadena en Tiempo Real de la Polimerasa , Resultado del Tratamiento , Regulación hacia Arriba
20.
Toxins (Basel) ; 5(2): 431-44, 2013 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-23430607

RESUMEN

Shiga toxin 1 (Stx1), produced by pathogenic Escherichia coli, targets a restricted subset of human cells, which possess the receptor globotriaosylceramide (Gb3Cer/CD77), causing hemolytic uremic syndrome. In spite of the high toxicity, Stx1 has been proposed in the treatment of Gb3Cer/CD77-expressing lymphoma. Here, we demonstrate in a Burkitt lymphoma cell model expressing this receptor, namely Raji cells, that Stx1, at quasi-non-toxic concentrations (0.05-0.1 pM), inhibits the repair of mafosfamide-induced DNA alkylating lesions, synergistically potentiating the cytotoxic activity of the anticancer drug. Conversely, human promyelocytic leukemia cells HL-60, which do not express Gb3Cer/CD77, were spared by the toxin as previously demonstrated for CD34+ human progenitor cells, and hence, in this cancer model, no additive nor synergistic effects were observed with the combined Stx1/mafosfamide treatment. Our findings suggest that Stx1 could be used to improve the mafosfamide-mediated purging of Gb3Cer/CD77+ tumor cells before autologous bone marrow transplantation.


Asunto(s)
Antineoplásicos/administración & dosificación , Ciclofosfamida/análogos & derivados , Inhibidores de la Síntesis de la Proteína/administración & dosificación , Toxina Shiga I/administración & dosificación , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Ciclofosfamida/administración & dosificación , Reparación del ADN/efectos de los fármacos , Sinergismo Farmacológico , Células HL-60 , Células Endoteliales de la Vena Umbilical Humana , Humanos
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