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1.
Actas urol. esp ; 48(2): 125-133, mar. 2024. graf, tab
Artículo en Español | IBECS | ID: ibc-231444

RESUMEN

Introducción El trasplante renal es el tratamiento de elección para pacientes con enfermedad renal crónica (ERC) estadio 5. Alrededor de 60% de los pacientes con ERC presentan sobrepeso u obesidad en el momento del trasplante de riñón, y la obesidad postrasplante se da en 50% de los pacientes, con un aumento de peso de 10% en el primer año y un alto riesgo de mortalidad cardiovascular. La obesidad se asocia a un mayor riesgo de retraso de la función del injerto (RFI), rechazo agudo, complicaciones quirúrgicas, pérdida del injerto y mortalidad. El objetivo de este estudio es evaluar la evolución clínica de los pacientes obesos y con sobrepeso receptores de un trasplante renal, en términos de las complicaciones a corto y largo plazo asociadas a un mayor índice de masa corporal (IMC). Material y métodos Se realizó un estudio descriptivo, observacional y transversal con 104 pacientes sometidos a trasplante de riñón o páncreas-riñón entre marzo de 2017 y diciembre de 2020, con seguimiento hasta abril de 2021. Para el análisis comparativo, los pacientes se agruparon según el IMC. Resultados La edad media fue de 56,65 años, 60,6% varones y 39,4% mujeres. Los pacientes con sobrepeso experimentaron cirugías más prolongadas, más dehiscencia de la herida quirúrgica, RFI, hernias, proteinuria y un requerimiento mayor de biopsias renales. Por otro lado, los pacientes obesos presentaron más RFI, mayor número de biopsias renales requeridas, proteinuria, desarrollo de diabetes mellitus y fibrilación auricular, y necesitaron estancias hospitalarias más prolongadas. Conclusiones A pesar de la alta prevalencia de comorbilidad en la población con sobrepeso y/u obesidad, no se observó un empeoramiento en la supervivencia del paciente y/o del injerto. Sin embargo, es necesario un seguimiento más prolongado. (AU)


Introduction Kidney transplantation is the treatment of choice for patients with stage 5 chronic kidney disease (CKD). About 60% of CKD patients are overweight or obese at the time of kidney transplantation, and post-transplant obesity occurs in 50% of patients, with a weight gain of 10% in the first year and high risk of cardiovascular mortality. Obesity is associated with an increased risk of delayed graft function (DGF), acute rejection, surgical complications, graft loss and mortality. The aim of this study is to assess the clinical evolution of obese and overweight patients that have received a kidney transplant, based on short- and long-term complications associated with a higher BMI. Material and methods A descriptive, observational, cross-sectional study was conducted with 104 kidney or pancreas-kidney transplant patients between March 2017 and December 2020, with a follow-up until April 2021. For comparative analysis, patients were grouped according to BMI. Results Mean age was of 56.65 years, 60.6% male and 39.4% female. Overweight patients experienced prolonged surgeries, more surgical wound dehiscence, delayed graft function, hernias, proteinuria and more indications for renal biopsies. Additionally, obese patients displayed more DGF, indications for renal biopsies, proteinuria, development of diabetes mellitus, atrial fibrillation and needed prolonged hospital stays. Conclusions Despite a high prevalence of comorbidity in the overweight and/or obese population, we found no reduction in patient and/or graft survival. However, longer follow-up is needed. (AU)


Asunto(s)
Humanos , Obesidad/complicaciones , Sobrepeso , Trasplante de Riñón , Epidemiología Descriptiva , Estudios Transversales
2.
Actas urol. esp ; 48(1): 2-10, Ene-Febr. 2024. tab
Artículo en Inglés, Español | IBECS | ID: ibc-229101

RESUMEN

Introducción La radiación es una herramienta fundamental en las técnicas de imagen ampliamente utilizadas en el manejo de los cálculos renales. Entre las medidas básicas que suelen adoptar los endourólogos para reducir la cantidad de exposición a la radiación, se encuentran el principio As Low As Reasonably Achievable (ALARA) —basado en reducir el uso de la radiación tanto como sea razonablemente posible— y el empleo de técnicas sin fluoroscopia. Se realizó una revisión exploratoria de la literatura para investigar el éxito y la seguridad de la ureteroscopia (URS) o la nefrolitotomía percutánea (NLPC) sin fluoroscopia para el tratamiento de los cálculos renales. Métodos Se realizó una revisión de la literatura mediante la búsqueda en las bases de datos bibliográficas PubMed, EMBASE y la biblioteca Cochrane, y se incluyeron en la revisión 14 artículos completos de acuerdo con las directrices de la declaración PRISMA. Resultados De un total de 2.535 procedimientos analizados, se realizaron 823 URS sin fluoroscopia frente a 556 URS con fluoroscopia, y 734 NLPC sin fluoroscopia frente a 277 NLPC con fluoroscopia. La tasa libre de cálculos (TLC) de la URS sin fluoroscopia frente a la guiada por fluoroscopia fue del 85,3 y el 77%, respectivamente (p=0,2), y las TLC de la NLPC sin fluoroscopia frente al grupo con fluoroscopia fueron del 83,8 y el 84,6%, respectivamente (p=0,9). Las complicaciones globales Clavien-Dindo I/II y III/IV para los procedimientos con y sin fluoroscopia fueron del 3,1 (n=71), 8,5 (n=131), 1,7 (n=23) y 3% (n=47), respectivamente. Solo 5 estudios informaron de un fracaso del abordaje realizado con fluoroscopia, con un total de 30 (1,3%) procedimientos fallidos. Conclusión Durante los últimos años han surgido diversas maneras de aplicar el protocolo ALARA en endourología en un esfuerzo por proteger tanto a los pacientes como al personal sanitario. ... (AU)


Introduction Radiation via the use of imaging is a key tool in management of kidney stones. Simple measures are largely taken by the endourologists to implement the ‘As Low As Reasonably Achievable’ (ALARA) principle, including the use of fluoroless technique. We performed a scoping literature review to investigate the success and safety of fluoroless ureteroscopy (URS) or percutaneous nephrolithotomy (PCNL) procedures for the treatment of KSD. Methods A literature review was performed searching bibliographic databases PubMed, EMBASE and Cochrane library, and 14 full papers were included in the review in accordance with the PRISMA guidelines. Results Of the 2535 total procedures analysed, 823 were fluoroless URS vs. 556 fluoroscopic URS; and 734 fluoroless PCNL vs. 277 fluoroscopic PCNL. The SFR for fluoroless vs. fluoroscopic guided URS was 85.3% and 77%, respectively (P=.2), while for fluoroless PCNL vs. fluoroscopic group was 83.8% and 84.6%, respectively (P=.9). The overall Clavien-Dindo I/II and III/IV complications for fluoroless and fluoroscopic guided procedures were 3.1% (n=71) and 8.5% (n=131), and 1.7% (n=23) and 3% (n=47) respectively. Only 5 studies reported a failure of the fluoroscopic approach with a total of 30 (1.3%) failed procedures. Conclusion The ALARA protocol has been implemented in endourology in numerous ways to protect both patients and healthcare workers during recent years. Fluoroless procedures for treatment of KSD are safe and effective with outcomes comparable to standard procedures and could become the new frontier of endourology in selected cases. (AU)


Asunto(s)
Humanos , Urología/métodos , Fluoroscopía/efectos adversos , Fluoroscopía/métodos , Fluoroscopía/tendencias , Ureteroscopía/métodos , Ureteroscopía/tendencias , Nefrolitotomía Percutánea , Urolitiasis , Cálculos Renales
3.
Actas Urol Esp (Engl Ed) ; 48(1): 2-10, 2024.
Artículo en Inglés, Español | MEDLINE | ID: mdl-37330050

RESUMEN

INTRODUCTION: Radiation via the use of imaging is a key tool in management of kidney stones. Simple measures are largely taken by the endourologists to implement the 'As Low As Reasonably Achievable' (ALARA) principle, including the use of fluoroless technique. We performed a scoping literature review to investigate the success and safety of fluoroless ureteroscopy (URS) or percutaneous nephrolithotomy (PCNL) procedures for the treatment of KSD. METHODS: A literature review was performed searching bibliographic databases PubMed, EMBASE and Cochrane library, and 14 full papers were included in the review in accordance with the PRISMA guidelines. RESULTS: Of the 2535 total procedures analysed, 823 were fluoroless URS vs. 556 fluoroscopic URS; and 734 fluoroless PCNL vs. 277 fluoroscopic PCNL. The SFR for fluoroless vs. fluoroscopic guided URS was 85.3% and 77%, respectively (p=0.2), while for fluoroless PCNL vs. fluoroscopic group was 83.8% and 84.6%, respectively (p=0.9). The overall Clavien-Dindo I/II and III/IV complications for fluoroless and fluoroscopic guided procedures were 3.1% (n=71) and 8.5% (n=131), and 1.7% (n=23) and 3% (n=47) respectively. Only 5 studies reported a failure of the fluoroscopic approach with a total of 30 (1.3%) failed procedures. CONCLUSION: The ALARA protocol has been implemented in endourology in numerous ways to protect both patients and healthcare workers during recent years. Fluoroless procedures for treatment of KSD are safe and effective with outcomes comparable to standard procedures and could become the new frontier of endourology in selected cases.


Asunto(s)
Cálculos Renales , Nefrolitotomía Percutánea , Humanos , Ureteroscopía/métodos , Nefrolitotomía Percutánea/métodos , Cálculos Renales/diagnóstico por imagen , Cálculos Renales/cirugía , Fluoroscopía/métodos
4.
Actas Urol Esp (Engl Ed) ; 48(2): 125-133, 2024 Mar.
Artículo en Inglés, Español | MEDLINE | ID: mdl-37604402

RESUMEN

INTRODUCTION: Kidney transplantation is the treatment of choice for patients with stage 5 chronic kidney disease (CKD). About 60% of CKD patients are overweight or obese at the time of kidney transplantation, and post-transplant obesity occurs in 50% of patients, with a weight gain of 10% in the first year and high risk of cardiovascular mortality. Obesity is associated with an increased risk of delayed graft function (DGF), acute rejection, surgical complications, graft loss and mortality. The aim of this study is to assess the clinical evolution of obese and overweight patients that have received a kidney transplant, based on short- and long-term complications associated with a higher BMI. MATERIAL AND METHODS: A descriptive, observational, cross-sectional study was conducted with 104 kidney or pancreas-kidney transplant patients between March 2017 and December 2020, with a follow-up until April 2021. For comparative analysis, patients were grouped according to BMI. RESULTS: Mean age was of 56.65 years, 60.6% male and 39.4 % female. Overweight patients experienced prolonged surgeries, more surgical wound dehiscence, delayed graft function, hernias, proteinuria and more indications for renal biopsies. Additionally, obese patients displayed more DGF, indications for renal biopsies, proteinuria, development of diabetes mellitus, atrial fibrillation and needed prolonged hospital stays. CONCLUSIONS: Despite a high prevalence of comorbidity in the overweight and/or obese population, we found no reduction in patient and/or graft survival. However, longer follow-up is needed.


Asunto(s)
Fallo Renal Crónico , Trasplante de Riñón , Humanos , Masculino , Femenino , Persona de Mediana Edad , Sobrepeso/complicaciones , Funcionamiento Retardado del Injerto/epidemiología , Funcionamiento Retardado del Injerto/complicaciones , Estudios Transversales , Rechazo de Injerto , Obesidad/complicaciones , Obesidad/epidemiología , Fallo Renal Crónico/complicaciones , Proteinuria/complicaciones
5.
Actas urol. esp ; 47(10): 631-637, Dic. 2023. tab
Artículo en Inglés, Español | IBECS | ID: ibc-228313

RESUMEN

Objetivo: Determinar la relación entre la impactación de los cálculos ureterales y la formación de estenosis ureterales y los factores asociados. Material y métodos Se analizaron retrospectivamente los registros médicos de todos los pacientes sometidos a cirugía endoscópica por cálculos ureterales impactados en 3 hospitales universitarios de Turquía, Reino Unido y España entre junio de 2019 y enero de 2022. Los parámetros examinados incluyeron los datos demográficos del paciente, lateralidad, tamaño y localización del cálculo, tiempo entre el inicio de los síntomas y la cirugía, tipo de ureteroscopia (rígida/flexible), presencia de nefrostomía o catéter doble J antes de la ureteroscopia, complicaciones intraoperatorias (avulsión/perforación), estado libre de cálculos, número de procedimientos necesarios para obtener un estado libre de cálculos y los resultados de las pruebas de imagen postoperatorias. Resultados Un total de 41 pacientes, 25 varones y 16 mujeres, de 3 instituciones fueron incluidos en el estudio. La edad media de los pacientes era de 48,2±13,5 años. La mediana del diámetro mayor de los cálculos fue de 9mm (RIC: 8mm). Catorce (34,1%) pacientes desarrollaron estenosis ureteral después de la ureteroscopia. No hubo diferencias entre los pacientes que desarrollaron estenosis ureteral y los que no la desarrollaron en cuanto a la lateralidad, la localización, la hidronefrosis y la multiplicidad de los cálculos (p=0,58, p=0,14, p=0,79 y p=0,31, respectivamente). Los pacientes que desarrollaron estenosis ureteral presentaron una tasa más elevada de derivación urinaria preoperatoria, como nefrostomía o catéter doble J (p=0,000). Conclusión La interrupción del paso de la orina por el uréter mediante derivación urinaria con nefrostomía o catéter doble J antes de la cirugía de cálculos ureterales podría favorecer la formación de estenosis ureteral en el postoperatorio. (AU)


Objective: To determine the relation between ureteral stone impaction and ureteral stricture formation and associated factors. Material and methods We retrospectively analyzed the medical records of all patients who underwent endoscopic ureteral stone surgery for impacted ureteral stone at 3 academic institutions in Turkey, United Kingdom and Spain between June 2019 and January 2022. Examined parameters included patient demographics, stone side, size and localization, time between initiation of symptoms and surgery, type of ureteroscopy (rigid/flexible), presence of nephrostomy or double-J stent prior to ureteroscopy, intraoperative complications (avulsion/perforation), stone-free status, number of procedures required for stone-free status, postoperative imaging results. Results A total of 41 patients whom 25 were male and 16 were female, from 3 institutions were included the study. The mean age of the patients was 48.2±13.5 years. The median largest diameter of the stones was 9mm (IQR: 8mm). Fourteen (34.1%) patients developed ureteral strictures following ureteroscopy. There was no difference between patients who developed ureteral strictures and patients who did not developed strictures in terms of stone laterality, stone location, hydronephrosis and multiplicity (p=0.58, p=0.14, p=0.79 and p=0.31, respectively). Patients who developed ureteral strictures had a higher rate of preoperative urinary diversion such as nephrostomy or double-J stent (p=0.000). Conclusion Interruption of urine passage through ureter via urinary diversion such as nephrostomy or double-J stent prior to ureteral stone surgery might lead ureteral stricture formation in the postoperative period. (AU)


Asunto(s)
Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Cálculos Ureterales/complicaciones , Cálculos Ureterales/terapia , Estrechez Uretral , Urolitiasis/terapia , Estudios Retrospectivos , Turquia , Reino Unido , España
6.
Actas Urol Esp (Engl Ed) ; 47(10): 631-637, 2023 Dec.
Artículo en Inglés, Español | MEDLINE | ID: mdl-37086846

RESUMEN

OBJECTIVE: To determine the relation between ureteral stone impaction and ureteral stricture formation and associated factors. MATERIAL AND METHODS: We retrospectively analyzed the medical records of all patients who underwent endoscopic ureteral stone surgery for impacted ureteral stone at three academic institutions in Turkey, United Kingdom and Spain between June 2019 and January 2022. Examined parameters included patient demographics, stone side, size and localization, time between initiation of symptoms and surgery, type of ureteroscopy (rigid/flexible), presence of nephrostomy or double-J stent prior to URS, intraoperative complications (avulsion/perforation, stone-free status, number of procedures required for stone-free status, postoperative imaging results. RESULTS: A total of 41 patients whom 25 were male and 16 were female, from 3 institutions were included the study. The mean age of the patients was 48.2 ±â€¯13.5 years. The median largest diameter of the stones was 9 mm (IQR: 8 mm). Total 14 (34.1%) patients developed ureteral strictures following ureteroscopy. There was no difference between patients who developed ureteral strictures and patients who did not developed strictures in terms of stone laterality, stone location, hydronephrosis and multiplicity, p = 0.58, p = 0.14, p = 0.79 and p = 0.31. Patients who developed ureteral strictures had a higher rate of preoperative urinary diversion such as nephrostomy or DJS, p = 0.000. CONCLUSION: Interruption of urine passage through ureter via urinary diversion such as nephrostomy or DJS stent prior to ureteral stone surgery might lead ureteral stricture formation in the postoperative period.


Asunto(s)
Cálculos Ureterales , Obstrucción Ureteral , Urolitiasis , Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Ureteroscopía/efectos adversos , Ureteroscopía/métodos , Constricción Patológica/etiología , Estudios Retrospectivos , Cálculos Ureterales/cirugía , Cálculos Ureterales/complicaciones , Urolitiasis/cirugía , Urolitiasis/complicaciones , Obstrucción Ureteral/etiología
7.
Radiat Prot Dosimetry ; 198(18): 1409-1416, 2022 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-36083112

RESUMEN

An accelerator-driven 14 MeV neutron source of new concept, denominated SORGENTINA-RF, will be installed in ENEA Brasimone Research Centre, to test the feasibility of producing radionuclides of medical relevance using fusion neutrons. The main goal of the facility is generating 99Mo as precursor of 99mTc, a radionuclide widely used in nuclear medicine diagnostic procedures, using the 14 MeV fusion neutrons produced by the plant. This work describes the study performed for the design of a proper shielding structure that aims at fulfilling the requirement of 0.01 mSv/h dose rate limit on the external surface of the shielding during beam-on operations. The proposed shielding consists of a layered structure composed of 2 m standard concrete and 1 m baritic concrete. The design is still in the preliminary phase to assess the feasibility and the economic issues as well as structural impact of the shielding structure.


Asunto(s)
Protección Radiológica , Radioisótopos , Humanos , Molibdeno , Protección Radiológica/métodos , Método de Montecarlo , Neutrones , Aceleradores de Partículas
8.
Urology ; 157: 222-226, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-33891927

RESUMEN

OBJECTIVE: To look at the safety and outcomes of using ureteral access sheath (UAS) for pediatric renal stones. The use of UAS is variable in urological practice with very little clinical work on their use in pediatric kidney stone disease. PATIENTS AND METHODS: Data was retrospectively collected from 2 large European tertiary endourology centers for all pediatric patients (≤16 years) with renal stones who underwent flexible ureteroscopy and lasertripsy (FURSL) via UAS. Data was collected on patient details, stone demographics and clinical outcomes of the FURSL procedure. RESULTS: Forty-eight patients with a mean age of 10.7 years were treated with FURSL for a mean single and cumulative stone size of 10.4 mm and 15 mm respectively, with two-third having multiple stones and stones in the lower pole. The initial and final stone free rate (SFR) was 66.7% and 100% respectively with 1.3 procedures/patient. One patient each had intra-operative grade 1 ureteric injury and post-operative UTI, with no other injuries or complications noted. Over a mean follow-up of 17 months, no other complications were noted. CONCLUSION: Ureteral access sheath is safe for treatment of pediatric renal stones with excellent outcomes and are especially useful for larger or multiple stones. While there does not seem to be any medium-term sequalae, to avoid risk of ureteral injury, we would suggest using the smallest size sheath possible. We would argue these procedures are best done in specialist high-volume endourology units for optimal results.


Asunto(s)
Cálculos Renales/cirugía , Ureteroscopios , Ureteroscopía/métodos , Adolescente , Niño , Preescolar , Diseño de Equipo , Femenino , Humanos , Lactante , Masculino , Estudios Retrospectivos , Centros de Atención Terciaria , Resultado del Tratamiento , Ureteroscopios/efectos adversos , Ureteroscopía/efectos adversos
9.
Urology ; 145: 38-51, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32640263

RESUMEN

We performed a systematic review to look at the role of alternative or complementary medicine such as music, acupressure, acupuncture, transcutaneous electrical nerve stimulation (TENS) and audiovisual distractions to decrease analgesia requirement and alleviate anxiety during SWL. Twenty-three papers(2439 participants) were included: Music (n = 1056.6%), Acupuncture (n = 517.7%), Acupressure (n = 13.8%), TENS (n = 617.2%), and audiovisual distraction (n = 14.6%). Most of the studies showed that complementary therapy, lowered pain, and anxiety with higher patient satisfaction and willingness to undergo the procedure. With its feasibility and convenience, urological guidelines need to endorse it, and more should be done to promote its use in outpatient urological procedures.


Asunto(s)
Analgesia , Ansiedad/prevención & control , Terapias Complementarias/métodos , Litotricia/psicología , Acupresión/estadística & datos numéricos , Terapia por Acupuntura/estadística & datos numéricos , Recursos Audiovisuales/estadística & datos numéricos , Terapias Complementarias/estadística & datos numéricos , Humanos , Musicoterapia/estadística & datos numéricos , Dolor Asociado a Procedimientos Médicos/prevención & control , Satisfacción del Paciente , Ensayos Clínicos Controlados Aleatorios como Asunto , Estimulación Eléctrica Transcutánea del Nervio/estadística & datos numéricos
10.
Scand J Urol ; 54(4): 339-343, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32686567

RESUMEN

INTRODUCTION: Treatment of smaller renal stones and the symptomatic value it offers to patients is often debated. We wanted to analyse surgical outcomes for treatment of small renal stones and whether treatment resulted in symptom resolution. MATERIALS AND METHODS: All patients who underwent ureterorenoscopy (URS) for isolated symptomatic small renal stones ≤10 mm over a 7-year period were retrospectively included and subdivided into those with stones of ≤7 mm (Group A) and stones of 8-10 mm (Group B). Patients with multiple renal stones, ureteric stones, or combined renal and ureteric stones were excluded. Based on the symptoms, the patient groups were those with pain, urinary tract infection (UTI) and haematuria. Resolution of symptoms was defined as no symptoms during the follow-up period. RESULTS: A total of 109 patients with a single small renal stone ≤10 mm underwent URS and stone treatment, with mean age of 50 years and a male:female ratio of 1:1.2. The mean operative time was significantly longer in Group B (55.9 min vs 33.07 min, p = 0.001). In total, 97.2% (n = 70) of patients in Group A and 83.7% (n = 31) of patients in Group B were stone free (p = 0.017). Complete resolution of symptoms was seen in 63 (92.6%), 24 (85.7%) and 13 (100%) patients with pain, UTI and haematuria, respectively. There were no statistically significant differences in symptom resolution between patients with stones ≤7 mm and those with stones 8-10 mm in size. CONCLUSION: Ureteroscopic treatment is a feasible option for small symptomatic stones, since it may lead to symptom resolution. Based on our study we would recommend that patients with symptomatic small renal stones are offered endoscopic treatment.


Asunto(s)
Cálculos Renales/cirugía , Ureteroscopía , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Femenino , Hospitales Universitarios , Humanos , Cálculos Renales/patología , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Resultado del Tratamiento , Adulto Joven
11.
Chem Sci ; 10(9): 2732-2742, 2019 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-30996991

RESUMEN

Several lines of evidence point to a compromised proteostasis associated with a reduction of the Ubiquitin Proteasome System (UPS) activity in patients affected by Alzheimer's Disease (AD) and suggest that the amyloid ß peptide (Aß) is an important player in the game. Inspired also by many reports, underlining the presence of ubiquitin (Ub) in the amyloid plaques of AD brains, here we set out to test whether Ub may bind the Aß peptide and have any effect on its clearance pathways. By using an integrated array of MALDI-TOF/UPLC-HRMS, fluorescence, NMR, SPR, Microscale Thermophoresis (MST) and molecular dynamics studies, we consistently demonstrated that Aß40 binds Ub with a 1 : 1 stoichiometry and K d in the high micromolar range. In particular, we show that the N-terminal domain of the Aß peptide (through residues D1, E3 and R5) interacts with the C-terminal tail of Ub (involving residues K63 and E64), inducing the central region of Aß (14HQKLVFFAEDVGSNK28) to adopt a mixed α-helix/ß-turn structure. ELISA assays, carried out in neuroblastoma cell lysates, suggest that Aß competitively binds Ub also in the presence of the entire pool of cytosolic Ub binding proteins. Ub-bound Aß has a lower tendency to aggregate into amyloid-like fibrils and is more slowly degraded by the Insulin Degrading Enzyme (IDE). Finally, we observe that the water soluble fragment Aß1-16 significantly inhibits Ub chain growth reactions. These results evidence how the non-covalent interaction between Aß peptides and Ub may have relevant effects on the regulation of the upstream events of the UPS and pave the way to future in vivo studies addressing the role played by Aß peptide in the malfunction of proteome maintenance occurring in AD.

12.
Appl Radiat Isot ; 134: 105-107, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29066213

RESUMEN

A severe supply crisis of 99Mo, precursor of 99mTc a diagnostic radionuclide largely used in Nuclear Medicine, occurred in 2008-2009 due to repeated shut-down of the two main (aged) fission reactors. An alternative route for producing 99Mo by 100Mo(n,2n)99Mo reaction was investigated at ENEA. The experiment, designed according to Monte Carlo simulations performed with the Fluka code, produced 99Mo by irradiating a natural Molybdenum powdered target with 14MeV neutrons produced at the Frascati Neutron Generator. The 99Mo specific activity was measured at metrological level by γ-ray spectrometry.

13.
Appl Radiat Isot ; 130: 264-269, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29054050

RESUMEN

Experimental tests are presented that assess the cross-talk level among three scintillation detectors used as neutron counters exploiting the thermal neutron radiative capture on Cd. The measurements were done at the INES diffractometer operating at the ISIS spallation neutron source (Rutherford Appleton Laboratory, UK). These tests follow a preliminary set of measurements performed on the same instrument to study the effectiveness of this thermal neutron counting strategy in neutron diffraction measurements, typically performed on INES using squashed 3He filled gas tubes. The experimental data were collected in two different geometrical configurations of the detectors and compared to results of Monte Carlo simulations, performed using the MCNP code.

14.
Appl Radiat Isot ; 127: 68-72, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28527348

RESUMEN

HOTNES (HOmogeneous Thermal NEutron Source) is a thermal neutron irradiation facility with extended and very uniform irradiation area. A 241Am-B radionuclide neutron source with nominal strenght 3.5×106 s-1 is located on bottom of a large cylindrical cavity (30cm diameter, 70cm in height) delimited by polyethylene walls. The upper part of this volume (30cm diameter, 40cm in height) is used to irradiate samples. A polyethylene cylinder, acting as shadowing object, prevents fast neutrons to directly reach the irradiation volume. Indeed neutrons can only reach the irradiation volume after multiple scattering with the cavity walls. The facility was designed trough extensive calculations with MCNPX. Irradiation planes are disks with 30cm diameter, centred on the cavity axis, and parallel to the cavity bottom. The value of thermal fluence in a given irradiation plane is as uniform as 1-2%. The value of thermal fluence rate simply depends on the height from the cavity bottom. Values of thermal fluence rate in the range 700-1000cm-2s-1 are available, depending on the irradiation plane chosen. The fraction of thermal neutrons is in the order of 90%, also depending on the irradiation plane. The angular distribution of thermal neutrons is roughly isotropic. Taking advantage of the HOTNES design, even large devices can be uniformly irradiated. This work presents HOTNES's design and describes the neutron field in the irradiation volume in terms of spatial, energy and direction distributions.

15.
Appl Radiat Isot ; 125: 129-133, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28431337

RESUMEN

Deuterium-Tritium (D-T) interactions produce almost monochromatic neutrons with about 14MeV energy. These neutrons are used in benchmark experiments as well as for neutron cross sections assessment in fusion reactors technology. The possibility to moderate 14MeV neutrons for purposes beyond fusion is worth to be studied in relation to projects of intense D-T sources. In this preliminary study, carried out using the MCNP Monte Carlo code, the moderation of 14MeV neutrons is approached foreseeing the use of combination of metallic materials as pre-moderator and reflectors coupled to standard water moderators.

16.
Rep Prog Phys ; 79(9): 094301, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27502571

RESUMEN

Neutron scattering techniques are attracting an increasing interest from scientists in various research fields, ranging from physics and chemistry to biology and archaeometry. The success of these neutron scattering applications is stimulated by the development of higher performance instrumentation. The development of new techniques and concepts, including radiative capture based neutron detection, is therefore a key issue to be addressed. Radiative capture based neutron detectors utilize the emission of prompt gamma rays after neutron absorption in a suitable isotope and the detection of those gammas by a photon counter. They can be used as simple counters in the thermal region and (simultaneously) as energy selector and counters for neutrons in the eV energy region. Several years of extensive development have made eV neutron spectrometers operating in the so-called resonance detector spectrometer (RDS) configuration outperform their conventional counterparts. In fact, the VESUVIO spectrometer, a flagship instrument at ISIS serving a continuous user programme for eV inelastic neutron spectroscopy measurements, is operating in the RDS configuration since 2007. In this review, we discuss the physical mechanism underlying the RDS configuration and the development of associated instrumentation. A few successful neutron scattering experiments that utilize the radiative capture counting techniques will be presented together with the potential of this technique for thermal neutron diffraction measurements. We also outline possible improvements and future perspectives for radiative capture based neutron detectors in neutron scattering application at pulsed neutron sources.

17.
Chem Commun (Camb) ; 51(86): 15724-7, 2015 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-26364617

RESUMEN

We report an ATP-dependent ubiquitin conjugation with IDE which, in turn, promotes Ub-Ub linkages in tube tests. We propose a novel function for IDE as a non-canonical ubiquitin activating enzyme.


Asunto(s)
Insulisina/química , Ubiquitina/química , Ubiquitinas/química , Adenosina Trifosfato/química , Ubiquitinación
18.
Urol Int ; 91(1): 81-8, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23485915

RESUMEN

OBJECTIVE: To investigate what changes are endoscopically evident after glycosaminoglycans (GAGs) therapy by hyaluronic acid (HA) and chondroitin sulphate (CS) (Ialuril®) in female patients affected by bladder pain syndrome(BPS)/ interstitial cystitis (IC) or recurrent urinary tract infections (rUTIs). PATIENTS AND METHODS: 21 female patients over 18 years affected by rUTIs or BPS/IC received intravesical instillation of HA and CS (4 weekly instillations followed by 2 instillations every 2 weeks and 2 instillation monthly). Post-treatment evaluation included cystoscopy and patient assessment of improvement in symptoms and satisfaction on a visual analogue scale (VAS) from 0 to 10. RESULTS: The post-treatment endoscopy showed a positive effect on bladder mucosa morphology. In 2 cases, treatment did not change endoscopic findings and clinical symptoms. In the other patients, when macroscopic features of the bladder mucosa normalized, the clinical picture improved. CONCLUSIONS: GAGs therapy by HA and CS (Ialuril) improves the morphology of bladder mucosa in patients with rUTI or BPS/IC.


Asunto(s)
Sulfatos de Condroitina/administración & dosificación , Cistitis Intersticial/tratamiento farmacológico , Ácido Hialurónico/administración & dosificación , Membrana Mucosa/patología , Vejiga Urinaria/patología , Infecciones Urinarias/tratamiento farmacológico , Adulto , Anciano , Sulfatos de Condroitina/uso terapéutico , Cistitis/tratamiento farmacológico , Cistoscopía , Combinación de Medicamentos , Endoscopía/métodos , Femenino , Glicosaminoglicanos/uso terapéutico , Humanos , Ácido Hialurónico/uso terapéutico , Persona de Mediana Edad , Enfermedades de la Vejiga Urinaria/tratamiento farmacológico , Urotelio/metabolismo , Urotelio/patología
19.
J Chem Phys ; 137(20): 204309, 2012 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-23206005

RESUMEN

In the present study we report neutron spectroscopic measurements on polycrystalline lithium imide, namely, incoherent inelastic neutron scattering at 20 K, and neutron Compton scattering from 10 K up to room temperature. From the former technique the H-projected density of phonon states up to 100 meV is derived, while the latter works out the spherically averaged single-particle (i.e., H, Li, and N) momentum distributions and, from this, the mean kinetic energies. Only for H at the lowest investigated temperature, non-gaussian components of its momentum distribution are detected. However, these components do not seem directly connected to the system anharmonicity, being fully compatible with the simple N-H bond anisotropy. Neutron data are also complemented by ab initio lattice dynamics simulations, both harmonic and, at room temperature, carried out in the framework of the so-called "quantum colored noise thermostat" method. The single-particle mean kinetic energies in lithium imide as a function of temperature show a quite peculiar behavior at the moment not reproduced by ab initio lattice dynamics methods, at least as far as H and Li are concerned. As matter of fact, neither their low temperature values nor their temperature trends can be precisely explained in terms of standard phonon calculations.

20.
J Chem Phys ; 136(2): 024504, 2012 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-22260600

RESUMEN

The spherical momentum distribution of the protons in ice is extracted from a high resolution deep inelastic neutron scattering experiment. Following a recent path integral Car-Parrinello molecular dynamics study, data were successfully interpreted in terms of an anisotropic Gaussian model, with a statistical accuracy comparable to that of the model independent scheme used previously, but providing more detailed information on the three dimensional potential energy surface experienced by the proton. A recently proposed theoretical concept is also employed to directly calculate the mean force from the experimental neutron Compton profile, and to evaluate the accuracy required to unambiguously resolve and extract the effective proton potential from the experimental data.


Asunto(s)
Hielo , Simulación de Dinámica Molecular , Protones , Difracción de Neutrones , Dispersión del Ángulo Pequeño
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