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1.
Appl Opt ; 62(34): 9089-9095, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38108746

RESUMO

Aluminum thin films were deposited on a 3D prototype employing the direct current magnetron sputtering technique to fabricate a lightweight 3D first surface mirror. Before the aluminizing, the surface of the prototypes was evaluated with interferometry and atomic force microscope (AFM). The thin films were characterized using profilometry, UV-Vis spectroscopy, x-ray diffraction, AFM, x-ray photoelectron spectroscopy (XPS), and scanning electron microscopy. High adherence and homogeneous deposition of the aluminum's thin films were achieved. In addition, the purity of the material was confirmed by XPS analysis.

2.
J Pharmacokinet Pharmacodyn ; 50(1): 33-43, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36478350

RESUMO

The building of population pharmacokinetic models can be described as an iterative process in which given a model and a dataset, the pharmacometrician introduces some changes to the model specification, then perform an evaluation and based on the predictions obtained performs further optimization. This process (perform an action, witness a result, optimize your knowledge) is a perfect scenario for the implementation of Reinforcement Learning algorithms. In this paper we present the conceptual background and a implementation of one of those algorithms aiming to show pharmacometricians how to automate (to a certain point) the iterative model building process.We present the selected discretization for the action and the state space. SARSA (State-Action-Reward-State-Action) was selected as the RL algorithm to use, configured with a window of 1000 episodes with and a limit of 30 actions per episode. SARSA was configured to control an interface to the Non-Parametric Optimal Design algorithm, that was actually performing the parameter optimization.The Reinforcement Learning (RL) based agent managed to obtain the same likelihood and number of support points, with a distribution similar to the reported in the original paper. The total amount of time used by the train the agent was 5.5 h although we think this time can be further improved. It is possible to automatically find the structural model that maximizes the final likelihood for an specific pharmacokinetic dataset by using RL algorithm. The framework provided could allow the integration of even more actions i.e: add/remove covariates, non-linear compartments or the execution of secondary analysis. Many limitations were found while performing this study but we hope to address them all in future studies.


Assuntos
Algoritmos , Reforço Psicológico , Fluxo de Trabalho , Probabilidade
3.
J Endocrinol Invest ; 44(6): 1327-1330, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32909176

RESUMO

INTRODUCTION: The prognosis of MEN 1 patients is not only determined by pancreatic disease; it is also related to other uncommon tumors. The objective of this study is to analyze the tumors associated with MEN 1 outside the classic triad and to investigate their relationship with mortality. MATERIALS AND METHODS: One hundred and five MEN 1 patients were studied in a tertiary referral hospital (1980-2019). RESULTS: With a follow-up of 11 ± 4 years, seven patients died (8%), four as a consequence MEN syndrome. Thirty-three percent had adrenal gland tumors. One patient died of adrenal cancer. Eight percent presented with a neuroendocrine thoracic neoplasm, and one patient died. Another patient died due to cutaneous T-cell lymphoma. A further patient died because of a gastrinoma with liver metastasis. CONCLUSIONS: To conclude, 75% of MEN-related deaths were the result of an uncommon pathology, and we, therefore, recommend that these tumors should be taken into account in the screening and follow-up of these patients.


Assuntos
Neoplasias das Glândulas Suprarrenais , Gastrinoma , Linfoma Cutâneo de Células T , Neoplasia Endócrina Múltipla Tipo 1 , Tumores Neuroendócrinos , Neoplasias Torácicas , Neoplasias das Glândulas Suprarrenais/mortalidade , Neoplasias das Glândulas Suprarrenais/patologia , Causas de Morte , Estudos de Coortes , Detecção Precoce de Câncer/métodos , Detecção Precoce de Câncer/normas , Feminino , Seguimentos , Gastrinoma/mortalidade , Gastrinoma/patologia , Humanos , Linfoma Cutâneo de Células T/mortalidade , Linfoma Cutâneo de Células T/patologia , Masculino , Pessoa de Meia-Idade , Neoplasia Endócrina Múltipla Tipo 1/diagnóstico , Neoplasia Endócrina Múltipla Tipo 1/mortalidade , Neoplasia Endócrina Múltipla Tipo 1/patologia , Estadiamento de Neoplasias , Tumores Neuroendócrinos/mortalidade , Tumores Neuroendócrinos/patologia , Prognóstico , Espanha/epidemiologia , Neoplasias Torácicas/mortalidade , Neoplasias Torácicas/patologia
4.
J Mater Sci Mater Med ; 31(10): 89, 2020 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-33057798

RESUMO

In this work, we present a method to fabricate a hyaluronic acid (HA) hydrogel with spatially controlled cell-adhesion properties based on photo-polymerisation cross-linking and functionalization. The approach utilises the same reaction pathway for both steps meaning that it is user-friendly and allows for adaptation at any stage during the fabrication process. Moreover, the process does not require any additional cross-linkers. The hydrogel is formed by UV-initiated radical addition reaction between acrylamide (Am) groups on the HA backbone. Cell adhesion is modulated by functionalising the adhesion peptide sequence arginine-glycine-aspartate onto the hydrogel surface via radical mediated thiol-ene reaction using the non-reacted Am groups. We show that 10 × 10 µm2 squares could be patterned with sharp features and a good resolution. The smallest area that could be patterned resulting in good cell adhesion was 25 × 25 µm2 squares, showing single-cell adhesion. Mouse brain endothelial cells adhered and remained in culture for up to 7 days on 100 × 100 µm2 square patterns. We see potential for this material combination for future use in novel organ-on-chip models and tissue engineering where the location of the cells is of importance and to further study endothelial cell biology.


Assuntos
Materiais Biocompatíveis/química , Técnicas de Cultura de Células/métodos , Hidrogéis/química , Oligopeptídeos/química , Compostos de Sulfidrila/química , Animais , Arginina/química , Ácido Aspártico/química , Encéfalo/metabolismo , Adesão Celular , Reagentes de Ligações Cruzadas/química , Células Endoteliais/metabolismo , Glicina/química , Ácido Hialurônico/química , Técnicas In Vitro , Cinética , Camundongos , Peptídeos/química , Polímeros/química , Estresse Mecânico , Engenharia Tecidual/métodos , Raios Ultravioleta
5.
Ethn Health ; 24(4): 443-461, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-28665141

RESUMO

INTRODUCTION: Medical students represent a new generation of medical thought, and if they have a favourable attitude towards organ donation this will greatly encourage its promotion. OBJECTIVE: To analyse the attitude of medical students in Spanish universities towards the donation of their own organs and to determine the factors affecting this attitude. MATERIAL AND METHODS: Type of study: A sociological, interdisciplinary, multicentre, and observational study in Spain. STUDY POPULATION: Students studying a degree in medicine enrolled in Spain (n = 34,000). SAMPLE SIZE: A sample of 9598 students (confidence of 99% and precision of ±1%), stratified by geographical area and academic year. Instrument of measurement: A validated questionnaire of attitude towards organ donation and transplantation (PCID-DTO RIOS) was self-administered and completed anonymously. RESULTS: The questionnaire completion rate was 95.7% (n = 9.275). 80% were in favour of donation, 2% against and 18% were undecided. The following main variables were related to a favourable attitude: being of the female sex (Odds Ratio = 1.739); being in the sixth year of the degree (OR = 2.506); knowing a donor (OR = 1.346); having spoken about the subject with one's family (OR = 2.132) and friends (OR = 1.333); having a family circle that is in favour, more specifically, having a father (OR = 1.841), mother (OR = 2.538) or partner in favour (OR = 2.192); being a blood donor (OR = 2.824); acceptance of the mutilation of the body if it were necessary (OR = 2.958); and being an atheist or an agnostic (OR = 1.766). CONCLUSIONS: Spanish medical students generally have a favourable attitude towards organ donation, although 20% are not in favour.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Estudantes de Medicina/psicologia , Obtenção de Tecidos e Órgãos/estatística & dados numéricos , Adulto , Feminino , Humanos , Masculino , Espanha , Inquéritos e Questionários , Doadores de Tecidos/provisão & distribuição
6.
Prog Transplant ; 28(1): 77-82, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29357760

RESUMO

OBJECTIVE: To analyze the level of understanding of the brain death concept among medical students in universities in Spain. METHODS: This cross-sectional sociological, interdisciplinary, and multicenter study was performed on 9598 medical students in Spain. The sample was stratified by geographical area and academic year. A previously validated self-reported measure of brain death knowledge (questionnaire Proyecto Colaborativo Internacional Donante sobre la Donación y Transplante de Organos) was completed anonymously by students. RESULTS: Respondents completed 9275 surveys for a completion rate of 95.7%. Of those, 67% (n = 6190) of the respondents understood the brain death concept. Of the rest, 28% (n = 2652) did not know what it meant, and the remaining 5% (n = 433) believed that it did not mean that the patient was dead. The variables related to a correct understanding of the concept were: (1) being older ( P < .001), (2) studying at a public university ( P < .001), (3) year of medical school ( P < .001), (4) studying at one of the universities in the south of Spain ( P = .003), (5) having discussed donation and transplantation with the family ( P < .001), (6) having spoken to friends about the matter ( P < .001), (7) a partner's favorable attitude toward donation and transplantation ( P < .001), and (8) religious beliefs ( P < .001). CONCLUSIONS: Sixty-seven percent of medical students know the concept of brain death, and knowledge improved as they advanced in their degree.


Assuntos
Morte Encefálica/classificação , Conhecimentos, Atitudes e Prática em Saúde , Estudantes de Medicina/psicologia , Adulto , Estudos Transversais , Feminino , Humanos , Masculino , Espanha , Inquéritos e Questionários , Adulto Jovem
7.
Langenbecks Arch Surg ; 401(6): 839-49, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27263038

RESUMO

INTRODUCTION: Between 40 and 50 % of the population will have at least one thyroid nodule, although only 5-8 % will have a malignant one. OBJECTIVE: The objective of this study was to establish the ultrasonographic characteristics which allow us to distinguish benignity from malignancy in thyroid nodules. METHODS: In the study population, inclusion criteria are (1) a single thyroid nodule and (2) multinodular goiter and exclusion criteria are (1) previous thyroid surgery and (2) fine needle aspiration (FNA) in the past month. This study is a double-blind prospective study. The study protocol is as follows: (1) clinical study; (2) ultrasound examination; (3) FNA; and (4) surgery-follow-up. The variables analysed are as follows: a multinodular nodule or goitre; colloid degeneration; morphology; margins; hyperechoic rim; rim thickness; rim morphology; size; angle between the major axis and the skin; echostructure; posterior acoustic findings; calcifications; thick colloid; localization of the intrathyroid nodular tissue; and characteristics in the Doppler scan. RESULTS: A total of 221 thyroid nodules were analysed. The following ultrasound findings were associated with malignancy (p < 0.05): a nodule with posterior acoustic shadowing; the echotexture of the nodule; intranodular colloid degeneration; nodule margins; nodular morphology; the presence of thick colloid; the angle between the major axis and the skin; characteristics of the intranodular vessels using color Doppler and Doppler energy; and calcifications. In the multivariate analysis, the following factors persisted as predictors of malignancy: the echotexture of the nodule (odds ratio 12.81), microcalcifications (OR 9.05), and chaotic vascularisation in the Doppler energy (OR 43.47). CONCLUSIONS: The high-resolution ultrasound allowed for a more reliable diagnosis of malignancy. The main findings of malignancy were the hypoechogenicity echotexture, microcalcifications, and chaotic intranodular vessels using Doppler energy.


Assuntos
Carcinoma/diagnóstico por imagem , Carcinoma/patologia , Nódulo da Glândula Tireoide/diagnóstico por imagem , Nódulo da Glândula Tireoide/patologia , Ultrassonografia Doppler em Cores , Adulto , Biópsia por Agulha Fina , Carcinoma/cirurgia , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Reprodutibilidade dos Testes , Fatores de Risco , Nódulo da Glândula Tireoide/cirurgia
8.
Stem Cell Res Ther ; 14(1): 365, 2023 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-38087374

RESUMO

BACKGROUND: The term sepsis refers to a complex and heterogeneous syndrome. Although great progress has been made in improving the diagnosis and treatment of this condition, it continues to have a huge impact on morbidity and mortality worldwide. Mesenchymal stem cells are a population of multipotent cells that have immunomodulatory properties, anti-apoptotic effects, and antimicrobial activity. We studied these capacities in a porcine model of peritoneal sepsis. METHODS: We infused human adipose-derived mesenchymal stem cells (ADSCs) into a porcine model of peritoneal sepsis. Twenty piglets were treated with antibiotics alone (control group) or antibiotics plus peritoneal infusion of ADSCs at a concentration of 2 × 106 cells/kg or 4 × 106 cells/kg (low- and high-dose experimental groups, respectively). The animals were evaluated at different time points to determine their clinical status, biochemical and hematologic parameters, presence of inflammatory cytokines and chemokines in blood and peritoneal fluid, and finally by histologic analysis of the organs of the peritoneal cavity. RESULTS: One day after sepsis induction, all animals presented peritonitis with bacterial infection as well as elevated C-reactive protein, haptoglobin, IL-1Ra, IL-6, and IL-1b. Xenogeneic ADSC infusion did not elicit an immune response, and peritoneal administration of the treatment was safe and feasible. One day after infusion, the two experimental groups showed a superior physical condition (e.g., mobility, feeding) and a significant increase of IL-10 and TGF-ß in blood and a decrease of IL-1Ra, IL-1b, and IL-6. After 7 days, all animals treated with ADSCs had better results concerning blood biomarkers, and histopathological analysis revealed a lower degree of inflammatory cell infiltration of the organs of the peritoneal cavity. CONCLUSIONS: Intraperitoneal administration of ADSCs as an adjuvant therapy for sepsis improves the outcome and diminishes the effects of peritonitis and associated organ damage by regulating the immune system and reducing intra-abdominal adhesions in a clinically relevant porcine model of abdominal sepsis.


Assuntos
Células-Tronco Mesenquimais , Peritonite , Sepse , Humanos , Animais , Suínos , Proteína Antagonista do Receptor de Interleucina 1/metabolismo , Interleucina-6/metabolismo , Células-Tronco Mesenquimais/metabolismo , Peritonite/terapia , Peritonite/metabolismo , Sepse/terapia , Sepse/metabolismo , Antibacterianos/metabolismo
9.
Pediatr Transplant ; 16(3): 274-9, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22309031

RESUMO

The aim of the study was to evaluate whether or not serum levels of soluble interleukin 2 receptor (sIL-2R) predict acute rejection in pediatric recipients. We studied 51 pediatric renal transplant recipients divided into three groups: Group 1) Biopsy-proven cellular acute rejection (n = 19), Group 2) Graft dysfunction with histological diagnosis other than acute rejection (n = 8) and Group 3) Patients with stable graft function, no biopsy (n = 24). Serum samples for sIL-2R measurement by sandwich ELISA were obtained at the time of renal transplant and at the time of renal biopsy due to graft dysfunction (Groups 1 and 2) or at six months post-transplant in the case of Group 3. The mean ± s.e. serum values of sIL-2R were higher in patients during acute rejection (6539 ± 1802 pg/mL) compared to patients with other causes of graft dysfunction (2217 ± 256 pg/mL) or stable graft function at six months (2183 ± 283 pg/mL) (Kruskal-Wallis p = 0.004). When the sIL2-R levels at the time of transplant were compared to those at the time of biopsy (Groups 1 and 2) or at six months post-transplant in Group 3, there was no significant difference between baseline and biopsy in the acute rejection group (paired t-test = 0.07), whereas there was a significant reduction in Groups 2 and 3.


Assuntos
Regulação da Expressão Gênica , Rejeição de Enxerto , Transplante de Rim/métodos , Receptores de Interleucina-2/sangue , Adolescente , Biópsia , Criança , Ensaio de Imunoadsorção Enzimática/métodos , Feminino , Taxa de Filtração Glomerular , Sobrevivência de Enxerto , Humanos , Transplante de Rim/efeitos adversos , Masculino , Estudos Prospectivos , Curva ROC , Reprodutibilidade dos Testes
10.
Hipertens Riesgo Vasc ; 39(2): 69-78, 2022.
Artigo em Espanhol | MEDLINE | ID: mdl-35331672

RESUMO

Statement of the Spanish Interdisciplinary Vascular Prevention Committee on the updated European Guidelines on Cardiovascular Disease Prevention. We present the Spanish adaptation of the 2021 European Guidelines on Cardiovascular Disease (CVD) prevention in clinical practice. The current guidelines besides the individual approach greatly emphasize on the importance of population level approaches to the prevention of cardiovascular diseases. Systematic global CVD risk assessment is recommended in individuals with any major vascular risk factor. Regarding LDL-Cholesterol, blood pressure, and glycemic control in patients with diabetes mellitus, goals and targets remain as recommended in previous guidelines. However, it is proposed a new, stepwise approach (Step 1 and 2) to treatment intensification as a tool to help physicians and patients pursue these targets in a way that fits patient profile. After Step 1, considering proceeding to the intensified goals of Step 2 is mandatory, and this intensification will be based on 10-year CVD risk, lifetime CVD risk and treatment benefit, comorbidities and patient preferences. The updated SCORE algorithm-SCORE2, SCORE-OP- is recommended in these guidelines, which estimates an individual's 10-year risk of fatal and non-fatal CVD events (myocardial infarction, stroke) in healthy men and women aged 40-89 years. Another new and important recommendation is the use of different categories of risk according different age groups (< 50, 50-69 ≥ 70 years). Different flow charts of CVD risk and risk factor treatment in apparently healthy persons, in patients with established atherosclerotic CVD, and in diabetic patients are recommended. Patients with chronic kidney disease are considered high risk or very high-risk patients according to the levels of glomerular filtration rate and albumin-to-creatinine ratio. New lifestyle recommendations adapted to the ones published by the Spanish Ministry of Health as well as recommendations focused on the management of lipids, blood pressure, diabetes and chronic renal failure are included.


Assuntos
Doenças Cardiovasculares , Diabetes Mellitus , Pressão Sanguínea , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/prevenção & controle , Feminino , Humanos , Estilo de Vida , Masculino , Fatores de Risco
11.
Diabetologia ; 54(3): 535-9, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21109996

RESUMO

AIM/HYPOTHESIS: Common variants in the transcription factor 7-like 2 (TCF7L2) gene have been associated with type 2 diabetes in adults. However, it is not known whether TCF7L2 variation increases the risk of early onset type 2 diabetes. Using a case-control design, we examined whether the reported variants [rs12255372 (T/G) and rs7903146 (T/C)] are associated with type 2 diabetes in SEARCH for Diabetes in Youth study participants. METHODS: Variants were genotyped in 694 non-Hispanic white (NHW) youth (86 cases, mean age 15.5 years, mean BMI 34.8; and 608 controls, mean age 14.4 years, mean BMI 22.3) and 545 African-American (AA) youth (154 cases, mean age 15.9, mean BMI 37; and 391 controls, mean age 14.8, mean BMI 23.8). Logistic regression adjusted for age, sex, BMI and West African ancestry. RESULTS: The association of the risk T allele with case/control status was different in AA and NHW youth (p = 0.025). Among AA youth, each copy of the T allele (rs7903146) was associated with a 1.97-fold (1.37, 2.82) increased odds for type 2 diabetes (p < 0.0001), after adjustment for age, sex, BMI and African ancestry. No significant association was detected in NHW youth (adjusted OR, 1.14; 0.73, 1.79). CONCLUSION/INTERPRETATION: TCF7L2 variation is associated with an increased risk of early-onset type 2 diabetes among AA youth, and the association appears to be stronger in AA than NHW youth. This suggests potential different contributions of genetic and environmental factors to early-onset type 2 diabetes by race.


Assuntos
Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/genética , Polimorfismo Genético/genética , Proteína 2 Semelhante ao Fator 7 de Transcrição/genética , Adolescente , Diabetes Mellitus Tipo 2/etnologia , Feminino , Predisposição Genética para Doença , Humanos , Masculino
12.
Rev Esp Enferm Dig ; 103(1): 20-4, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21341933

RESUMO

OBJECTIVE: To describe the experience with upper gastrointestinal bleeding in two major Latin American hospitals; presenting its main causes, treatment, and prognosis, while exploring some risk factors associated with death. DESIGN: Prospective cohort study. PATIENTS AND METHODS: Four hundred and sixty four patients were admitted into any of the 2 hospitals and were at least 15 years of age. Some variables demographics, clinics and treatment were studied. The association between those variables and the death were explored. RESULTS: Mean age was 57.9 years; the men:women ratio was 1.4:1. Three hundred and fifty nine patients (77.3%) presented as outpatients and 105 patients (22.6%) were inpatients presenting with UGIB. 71.6% of patients had an upper GI endoscopy within 24 hours. The main causes of bleeding were peptic ulcer (190 patients, 41%), erosive disease (162 patients, 34.9%) and variceal bleeding (47 patients, 10.1%). Forty four patients died (9.5%). Bleeding as an inpatient has a higher mortality risk than does bleeding as an outpatient (RR 2.4 IC 95% 1.2-4.6). An increasing number of comorbidities such as those described in the Rockall Score are also associated with a higher risk of dying (RR 2.5 IC 95% 1.1-5.4). CONCLUSION: UGIB as an inpatient and the presence of comorbidities should alert the clinician in identifying patients at higher risk of a fatal outcome, these patients should have a more aggressive management and be entitled to an early intervention.


Assuntos
Varizes Esofágicas e Gástricas/mortalidade , Hemorragia Gastrointestinal/mortalidade , Adulto , Idoso , Anticoagulantes/efeitos adversos , Colômbia/epidemiologia , Comorbidade , Úlcera Duodenal/mortalidade , Embolização Terapêutica , Endoscopia do Sistema Digestório , Esofagite/complicações , Esofagite/mortalidade , Feminino , Hemorragia Gastrointestinal/etiologia , Hemorragia Gastrointestinal/terapia , Hospitais Gerais/estatística & dados numéricos , Hospitais Universitários/estatística & dados numéricos , Hospitais Urbanos/estatística & dados numéricos , Humanos , Pacientes Internados/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Pacientes Ambulatoriais/estatística & dados numéricos , Úlcera Péptica Hemorrágica/mortalidade , Estudos Prospectivos , Fatores de Risco , Neoplasias Gástricas/complicações , Neoplasias Gástricas/mortalidade , Úlcera Gástrica/mortalidade
13.
Med Intensiva (Engl Ed) ; 45(4): 226-233, 2021 May.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-31870509

RESUMO

OBJECTIVE: To evaluate the diagnostic accuracy of diaphragmatic ultrasound in predicting extubation success. DESIGN: A diagnostic accuracy study was carried out. SCOPE: Intensive Care Unit of an Academic hospital in the city of Bogotá (Colombia). PATIENTS OR PARTICIPANTS: A consecutive sample of patients >18 years of age subjected to invasive mechanical ventilation for >48h. INTERVENTIONS: Diaphragmatic ultrasound evaluation at the end of spontaneous ventilation testing. MAIN VARIABLES OF INTEREST: Diaphragmatic excursion (DE, cm), inspiration time (TPIAdia, s), diaphragm contraction speed (DE/TPIAdia, cm/s) and total time (Ttot, s) were evaluated, together with thickening fraction (TFdi, %). RESULTS: A total of 84 patients were included, 79.8% (n=67) with successful extubation and 20.2% (n=17) with failed extubation. The variable with the best discriminatory capacity in predicting extubation success was diaphragm contraction speed, with AUC-ROC 0.70 (p=0.008). CONCLUSIONS: Diaphragm contraction speed exhibited acceptable discriminatory capacity. Ultrasound could be part of a multifactorial approach in the extubation process.

14.
Pediatr Transplant ; 14(6): 746-52, 2010 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-20412508

RESUMO

The aim of the study was to evaluate the efficacy and safety of the conversion of MMF to EC-MPS in pediatric renal transplant recipients. We included 12 patients with stable graft function who were receiving MMF treatment. In the first visit, a complete medical examination was performed, which included a GSRS, a nine-point pharmacokinetic profile, samples for renal, liver and hematological tests and evaluation of IMPDH2 gene expression. The patients were transferred to an equimolar dose of EC-MPS. Two wk later, a clinical evaluation and blood collection, as in the first visit were performed. There was no change in serum creatinine, leukocyte count, serum albumin, or transaminase levels, but we found a statistically significant reduction of hemoglobin after conversion (13.2 +/- 1.6 g/dL with MMF vs. 12.5 +/- 1.3 g/dL when receiving EC-MPS). The GSRS total mean score was 16 +/- 12 with MMF vs. 8 +/- 5 with EC-MPA (p < 0.05). There was no statistically significant difference between formulations in the gene expression of IMPDH 2, in the AUC(0-12h) or in C(max). However, peak concentration occurred later with EC-MPS.


Assuntos
Substituição de Medicamentos , Imunossupressores/farmacocinética , Transplante de Rim , Ácido Micofenólico/análogos & derivados , Ácido Micofenólico/farmacocinética , Adolescente , Área Sob a Curva , Criança , Feminino , Humanos , Imunossupressores/uso terapêutico , Transplante de Rim/imunologia , Masculino , Ácido Micofenólico/uso terapêutico , Estudos Prospectivos , Comprimidos com Revestimento Entérico
15.
J Med Genet ; 46(7): 458-64, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19357115

RESUMO

BACKGROUND: Mutations in the leucine-rich-repeat kinase 2 (LRRK2) gene have been identified in families with autosomal dominant Parkinson's disease (ADPD), the most common of which is the p.G2019S substitution that has been found at varying frequencies worldwide. Because of the size of the LRRK2 gene, few studies have analysed the entire gene in large series of ADPD families. METHODS: We performed extensive mutation analyses of all 51 coding exons of the LRRK2 gene in index cases from 226 Parkinson's disease families compatible with autosomal dominant inheritance, mostly from France (n = 182) and North Africa (n = 14). RESULTS: We found 79 sequence variants, 29 of which were novel. Eight potentially or proven pathogenic mutations were found in 22 probands (9.7%). There were four novel amino acid substitutions that are potentially pathogenic (p.S52F, p.N363S, p.I810V, p.R1325Q) and two novel variants, p.H1216R and p.T1410M, that are probably not causative. The common p.G2019S mutation was identified in 13 probands (5.8%) including six from North Africa (43%). The known heterozygous p.R1441H and p.I1371V mutations were found in two probands each, and the p.E334K variant was identified in one single patient. Most potentially or proven pathogenic mutations were located in the functional domains of the Lrrk2 protein. CONCLUSION: This study leads us to conclude that LRRK2 mutations are a common cause of autosomal dominant Parkinson's disease in Europe and North Africa.


Assuntos
Transtornos Parkinsonianos/genética , Proteínas Serina-Treonina Quinases/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , População Negra/genética , Distribuição de Qui-Quadrado , Análise Mutacional de DNA/métodos , Feminino , Frequência do Gene , Humanos , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina , Masculino , Pessoa de Meia-Idade , Mutação , Transtornos Parkinsonianos/diagnóstico , Linhagem , População Branca/genética
16.
Med Phys ; 47(2): 467-479, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31808950

RESUMO

PURPOSE: A modular phantom for dosimetry and imaging performance evaluation in cone-beam computed tomography (CBCT) is reported, providing a tool for quantitative technical assessment that can be adapted to a broad variety of CBCT imaging configurations and clinical applications. METHODS: The phantom presents a set of modules that can be ordered in various configurations suitable to a particular CBCT system. Modules include slabs containing a uniform medium, low-contrast inserts, line-spread features, and disk features suitable to measurement of image uniformity, noise, noise-power spectrum (NPS), contrast, contrast-to-noise ratio (CNR), Hounsfield (HU) accuracy, linearity, spatial resolution modulation transfer function (MTF), and magnitude of cone-beam artifact. Automated software recognizes the phantom configuration in DICOM images and provides structured reporting of such test measures. In any modular configuration, the phantom permits measurement of air kerma in central and peripheral locations with an air ionization chamber (e.g., Farmer chamber). The utility and adaptability of the phantom were demonstrated across a spectrum of CBCT systems, including scanners for orthopaedic imaging (Carestream OnSight 3D, Rochester NY), breast imaging (Doheny prototype, UC Davis), image-guided surgery (IGS, Medtronic O-arm, Littleton MA), angiography (Siemens Artis Zeego, Forcheim Germany), and image-guided radiation therapy (IGRT, Elekta Synergy XVI, Stockholm Sweden). RESULTS: The phantom provided a consistent platform for quantitative assessment of dose and imaging performance compatible with a broad spectrum of CBCT systems. The purpose of the survey was not to obtain head-to-head performance comparison of systems designed for such distinct clinical applications. Rather, the survey demonstrated the suitability of the phantom to a broad spectrum of systems in a manner that provides characterization pertinent to disparate applications and imaging tasks. For example: the orthopaedic CBCT system (pertinent clinical tasks relating to high-resolution bone imaging) was shown to achieve MTF consistent with imaging of high-contrast trabecular bone structures (i.e., the MTF reduced to 10% at spatial frequency, f 10  = 1.2 mm-1 ); the breast system (even higher-resolution imaging of microcalcifications) exhibited f 10  = 2.2 mm-1 ; the IGS system (tasks including both bone and soft-tissue contrast resolution) provided f 10  = 0.9 mm-1 and soft-tissue CNR  = 1.64; the angiography system (soft-tissue body interventions) demonstrated CNR  = 1.2 in soft tissues approximating liver lesions; and the IGRT system (pertinent tasks emphasizing HU linearity and image uniformity) showed linear response with HU values ( R 2  = 1), with a cupping artifact ( t cup  = 5.8%) due to x-ray scatter. CONCLUSIONS: The phantom provides an adaptable, quantitative basis for CBCT dosimetry and imaging performance evaluation suitable to a broad variety of CBCT systems. The dosimetry and image quality metrics are consistent with up-to-date methods for rigorous, quantitative, physics testing and should be suitable to emerging standards for CBCT quality assurance.


Assuntos
Tomografia Computadorizada de Feixe Cônico/instrumentação , Imagens de Fantasmas , Doses de Radiação , Artefatos , Controle de Qualidade , Razão Sinal-Ruído
17.
Phys Med ; 74: 133-142, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32470909

RESUMO

Virtual clinical trials (VCT) are in-silico reproductions of medical examinations, which adopt digital models of patients and simulated devices. They are intended to produce clinically equivalent outcome data avoiding long execution times, ethical issues related to radiation induced risks and huge costs related to real clinical trials with a patient population. In this work, we present a platform for VCT in 2D and 3D X-ray breast imaging. The VCT platform uses Monte Carlo simulations based on the Geant4 toolkit and patient breast models derived from a cohort of high resolution dedicated breast CT (BCT) volume data sets. Projection images of the breast and three-dimensional glandular dose maps are generated for a given breast model, by simulating both 2D full-field digital mammography (DM) and 3D BCT examinations. Uncompressed voxelized breast models were derived from segmented patient images. Compressed versions of the digital breast phantoms for DM were generated using a previously published digital compression algorithm. The Monte Carlo simulation framework has the capability of generating and tracking ~105 photons/s using a server equipped with 16-cores and 3.0 GHz clock speed. The VCT platform will provide a framework for scanner design optimization, comparison between different scanner designs and between different modalities or protocols on computational breast models, without the need for scanning actual patients as in conventional clinical trials.


Assuntos
Mama/diagnóstico por imagem , Ensaios Clínicos como Assunto , Mamografia , Método de Monte Carlo , Humanos , Imageamento Tridimensional
18.
Arch Soc Esp Oftalmol (Engl Ed) ; 95(9): 421-428, 2020 Sep.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-32563627

RESUMO

PURPOSE: Neurotrophic corneal ulcers are difficult to treat, and the conventional treatment often results in failure. A new matrix regenerating agent ("ReGeneraTing Agents"), Cacicol® (Laboratoires Théa), has demonstrated good results over the last few years. Therefore, the aim of this study was to evaluate the response to Cacicol® in a series of cases with neurotrophic corneal ulcers. METHODS: Retrospective case series looking at 11 patients with corneal ulcers unresponsive to conventional therapy that underwent treatment with Cacicol®. One cycle included 1 drop every two days for 5 days. RESULTS: The range of conventional therapy prior to Cacicol® was 0-91 days. On introducing Cacicol® 82% (9/11) of the cases were cured, and 18% (2/11) failed, requiring an amniotic membrane transplant or penetrating keratoplasty. The healing only required one cycle of Cacicol® in 67% (6/9) of the patients. More than one cycle of Cacicol® was needed in 45% (5/11) patients. One corneal bacterial ulcer responded favourably and one case related to Acanthamoeba did not respond. Most of the patients improved or maintained their visual acuity. CONCLUSION: Cacicol® was a useful therapy in a high number of difficult neurotrophic corneal ulcers, including corneal infections. Some cases may require more than one cycle of Cacicol® or used as first-line treatment in order to achieve the desired result.

19.
Comput Methods Programs Biomed ; 182: 105034, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31454749

RESUMO

BACKGROUND AND OBJECTIVE: Outpatient vital signs monitoring has a key role in medical diagnosis and treatment. However, ambulatory vital signs monitoring has great challenges to overcome, being the most important, the reduction of noise and Motion Artifacts, which hide essential information, particularly in Electrocardiographic signals. Despite efforts being made to reduce these artifacts, a comparative performance assessment of proposed techniques does not exist to the best of our knowledge and there are no enhancement level measurements obtained by the signals in the artifacts reduction. This article presents a new method based on Ensemble Average for the performance comparison of reported techniques for the processing and reduction of noise and artifacts in Electrocardiographic signals. METHODS: The comparison was done using a dataset composed by six synthetic noised Electrocardiographic signals and six real one acquired from healthy volunteers that intentionally introduced Motion Artifacts. Several techniques that have reported positive results in the enhancement of Electrocardiographic signals were applied to this dataset to compare their performance in the reduction of Motion Artifacts. The Signal-to-Noise Ratio and the Ensemble Average as a distortion measurement were used to compare the performance of algorithms to produce an enhanced signal. RESULTS: In agreement to previous reports, all studied methods show a significant improvement of the Signal-to-Noise Ratio. Concerning the distortion of the waveform, although all methods caused high distortion on the enhanced signal waveform, the Wavelet-ICA method showed the best performance. The percentage of signal distortion introduced by denoising techniques was evaluated through the proposed Ensemble Average Electrocardiographic method. CONCLUSIONS: It was found that the proposed method based on Ensemble Average offers a complementary way to measure the performance of denoising techniques when considering the introduced distortion in the waveform segments once the artifact reduction process was applied and not only the change in the Signal-to-Noise Ratio.


Assuntos
Artefatos , Eletrocardiografia/métodos , Razão Sinal-Ruído , Processamento de Sinais Assistido por Computador
20.
Transplant Proc ; 51(2): 269-272, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30879518

RESUMO

INTRODUCTION: The population from Mali is migrating toward Europe in a significant way. OBJECTIVE: To analyze the attitude toward organ donation (ODT) among the population born in Mali who are currently residents in Spain. METHOD: Study population: people born in Mali who are ≥15 years of age and residents of Spain, stratified by age and sex. The assessment instrument is the validated attitude questionnaire toward organ donation (PCID-DTO-Ríos). Fulfillment was anonymous and self-administred. The statistics used were descriptive, χ2 test, Student t test, and a logistic regression analysis. RESULTS: This study surveyed 402 Malians. Thirty-four percent (n = 136) are in favor of donating their own organs after dying, 39% (n = 156) are against organ donation, and 27% (n = 110) are undecided. Multiple factors are associated with this attitude, such as level of studies (P = .042, OR = 6.535), having a positive attitude toward ODT (P = .001, OR = 47.619), performing prosocial activities (P = .001, OR = 141.679), being familiar with the scope of the transplant (P < .001, OR = 16.949), the attitude toward the incineration of the body (P = .002, OR = 8.928) and toward autopsy (P = .003, OR = 8.620), having had a prior donation or transplantation relationship (P = .001, OR = 17.910) and not having concerns about the possible mutilation of the body after donating (P < .001; OR = 90.909). CONCLUSIONS: The Malians have an unfavorable attitude toward the donation of their own organs, which is conditioned by multiple psychosocial factors.


Assuntos
Emigrantes e Imigrantes/psicologia , Conhecimentos, Atitudes e Prática em Saúde/etnologia , Obtenção de Tecidos e Órgãos , Adolescente , Adulto , Feminino , Humanos , Masculino , Mali , Pessoa de Meia-Idade , Análise Multivariada , Transplante de Órgãos/psicologia , Espanha , Inquéritos e Questionários
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