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1.
Curr Biol ; 34(1): 56-67.e5, 2024 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-38118450

RESUMO

Spider orb webs have evolved to stop flying prey, fast and slow alike. One of the main web elements dissipating impact energy is the radial fibers, or major ampullate silks, which possess a toughness surpassing most man-made materials. Orb webs are extended phenotypes, and as such their architectural elements, including major ampullate silks, have been selected to optimize prey capture under the respective environmental conditions. In this study, we investigated the correlation of three landscape scales and three microhabitat characteristics with intrinsic silk properties (elastic modulus, yield stress, tensile strength, extensibility, and toughness) to understand underlying ecological patterns. For this purpose, we collected and mechanically tested major ampullate silks from 50 spider species inhabiting large altitudinal and climatic gradients in Colombia. Using regression analysis and model selection, we investigated the environmental drivers of inter- and intra-specific patterns of major ampullate silk properties, taking into account phylogenetic relatedness based on newly sequenced mitochondrial genomes. We found that the total amount of energy absorbed, i.e., toughness and tensile strength, is higher for fibers from species inhabiting regions where heavy rainfall is common. Interestingly, we observe the same general trend between individuals of the same species, stressing the importance of this environmental driver. We also observe a phylogenetic conservation in the relation of environmental variables with silk tensile strength and yield stress. In conclusion, the increase in major ampullate silk tensile strength and toughness may reflect an adaptation to prevent frequent rain damage to orb webs and the associated energetic loss.


Assuntos
Seda , Aranhas , Animais , Sequência de Bases , Filogenia , Análise de Regressão , Aranhas/genética , Resistência à Tração
2.
Cureus ; 15(7): e42370, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37621804

RESUMO

Robotic surgery (RS) is an evolution of minimally invasive surgery that combines medical science, robotics, and engineering. The first robots approved by the Food and Drug Administration (FDA) were the Da Vinci Surgical System and the ZEUS Robotic Surgical System, which have been improving over time. Through the decades, the equipment applied to RS had undergone a wide transformation as a response to the development of new techniques and facilities for the assembly and implementation of the own. RS has revolutionized the field of urology, enabling surgeons to perform complex procedures with greater precision and accuracy, and many other surgical specialties such as gynecology, general surgery, otolaryngology, cardiothoracic surgery, and neurosurgery. Several benefits, such as a better approach to the surgical site, a three-dimensional image that improves depth perception, and smaller scars, enhance range of motion, allowing the surgeon to conduct more complicated surgical operations, and reduced postoperative complications have made robotic-assisted surgery an increasingly popular approach. However, some points like the cost of surgical procedures, equipment-instrument, and maintenance are important aspects to consider. Machine learning will likely have a role to play in surgical training shortly through "automated performance metrics," where algorithms observe and "learn" individual surgeons' techniques, assess performance, and anticipate surgical outcomes with the potential to individualize surgical training and aid decision-making in real time.

3.
Phys Med Biol ; 67(18)2022 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-36093921

RESUMO

Objective.To establish an open framework for developing plan optimization models for knowledge-based planning (KBP).Approach.Our framework includes radiotherapy treatment data (i.e. reference plans) for 100 patients with head-and-neck cancer who were treated with intensity-modulated radiotherapy. That data also includes high-quality dose predictions from 19 KBP models that were developed by different research groups using out-of-sample data during the OpenKBP Grand Challenge. The dose predictions were input to four fluence-based dose mimicking models to form 76 unique KBP pipelines that generated 7600 plans (76 pipelines × 100 patients). The predictions and KBP-generated plans were compared to the reference plans via: the dose score, which is the average mean absolute voxel-by-voxel difference in dose; the deviation in dose-volume histogram (DVH) points; and the frequency of clinical planning criteria satisfaction. We also performed a theoretical investigation to justify our dose mimicking models.Main results.The range in rank order correlation of the dose score between predictions and their KBP pipelines was 0.50-0.62, which indicates that the quality of the predictions was generally positively correlated with the quality of the plans. Additionally, compared to the input predictions, the KBP-generated plans performed significantly better (P< 0.05; one-sided Wilcoxon test) on 18 of 23 DVH points. Similarly, each optimization model generated plans that satisfied a higher percentage of criteria than the reference plans, which satisfied 3.5% more criteria than the set of all dose predictions. Lastly, our theoretical investigation demonstrated that the dose mimicking models generated plans that are also optimal for an inverse planning model.Significance.This was the largest international effort to date for evaluating the combination of KBP prediction and optimization models. We found that the best performing models significantly outperformed the reference dose and dose predictions. In the interest of reproducibility, our data and code is freely available.


Assuntos
Planejamento da Radioterapia Assistida por Computador , Radioterapia de Intensidade Modulada , Humanos , Bases de Conhecimento , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia de Intensidade Modulada/métodos , Reprodutibilidade dos Testes
4.
Neurol Int ; 14(1): 284-293, 2022 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-35324579

RESUMO

Here, a study of NMOSD in Central America and the Caribbean with a multinational collaborative, multicentric and descriptive approach involving 25 institutions from 9 countries is presented. Demographics, clinical manifestations, expanded disability scale status (EDSS), brain and spinal cord MRI, serological anti-AQP4-IgG and anti-MOG-IgG antibodies, and cerebrospinal fluid (CSF) oligoclonal bands were included. A central serological repository utilized the cell-based assay. The specimens outside of this network employed diverse methodologies. Data were collected at the Gorgas Commemorative Institute of Health Studies (ICGES), Panama, and included 186 subjects, of which 84% were females (sex ratio of 5.6:1). Mestizos constituted 72% of the study group. The median age was 42.5 years (IQR: 32.0-52.0). Associated autoimmune diseases (8.1%) were myasthenia gravis, Sjögren's syndrome and systemic lupus erythematosus. The most common manifestation was optic neuritis-transverse myelitis (42.5%). A relapsing course was described in 72.3% of cases. EDSS scores of 0-3.5 were reported in 57.2% of cases and higher than 7.0 in 14.5%. Positive anti-AQP4-IgG antibody occurred in 59.8% and anti-MOG-IgG antibody in 11.5% of individuals. Antibody testing was lacking for 13.4% of patients. The estimated crude prevalence of NMOSD from Panama and the Dominican Republic was 1.62/100,000 (incidence of 0.08-0.41) and 0.73/100,000 (incidence 0.02-0.14), respectively. This multinational study contributes additional insights and data on the understanding of NMOSD in this Latin American region.

5.
Sci Total Environ ; 806(Pt 2): 150604, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34597564

RESUMO

Climate change-induced mortality of trees is a concerning phenomenon for global forest ecosystems. The rapid decay and death of long-lived trees can significantly impact forest dynamics, with effects that transmit through ecological networks, becoming more evident in organisms occupying high trophic levels, such as large and specialized woodpecker species. However, understanding how populations of high trophic level species respond to climate change is still a challenge. In this study it was analyzed 32-year data of social groups of the Magellanic Woodpecker (Campephilus magellanicus) in North Patagonia, a region facing increasingly frequent droughts and increased temperatures. A positive trend in the size of woodpecker social groups as a response to climate-induced tree senescence was tested. A causal structural equation model examining climate- tree senescence- woodpecker relationships was used. Increasing nonlinear trends and positive interannual growth rates (>10%) for tree senescence and group size were found. Lowland forest sites had higher levels of tree senescence and more numerous social groups. The causal model supported the positive effect of mean temperature on tree senescence and the positive association of woodpeckers with tree senescence. These results provide evidence of a climate-induced increase in tree senescence that causes an increase in the size of woodpecker social groups. It is suggested that accelerated decay and mortality of trees in the northern Patagonian forests will decrease the stocks of deadwood in the long term, threatening the persistence of this large woodpecker species.


Assuntos
Ecossistema , Árvores , Mudança Climática , Secas , Florestas
6.
Rev. chil. ortop. traumatol ; 62(3): 201-207, dic. 2021.
Artigo em Espanhol | LILACS | ID: biblio-1434883

RESUMO

La artrosis es una enfermedad progresiva de las articulaciones sinoviales que causa dolor, impotencia funcional, discapacidad, y degeneración progresiva de la articulación. En sus tratamientos, sobre todo en etapas tempranas, existen distintas intervenciones para evitar tanto su desarrollo y progresión como también para lograr un adecuado manejo de los síntomas, y hay tratamientos médicos orales no convencionales con evidencia controvertida. El objetivo de este trabajo es proporcionar una actualización, dirigida a especialistas en Ortopedia y Traumatología, respecto a la evidencia actual sobre las terapias complementarias orales en el tratamiento de la artrosis de rodilla. Se hace referencia a los métodos fármacológicos complementarios más usados y estudiados, mencionando el método de acción y las consecuencias estudiadas sobre la artrosis de rodilla. Se finaliza con una tabla de recomendaciones basada en evidencia actual.


Osteoarthritis (OA) is a progressive disease of the synovial joints that causes pain, functional impairment, disability, and progressive degeneration of the joint. Regarding its treatments, especially in early stages, there are different interventions to avoid its development and progression and also to achieve an adequate management of symptoms, and there are unconventional oral medical treatments with controversial evidence. The objective of the present paper is to provide an update, to specialists in Orthopedics and Traumatology, regarding the current evidence on complementary oral therapies in the treatment of knee osteoarthritis. References are made to the most widely used and studied complementary pharmacological methods, mentioning the method of action and the consequences studied on knee osteoarthritis. The article ends with a table of recommendations based on current evidence.


Assuntos
Humanos , Patela/cirurgia , Fraturas Cominutivas/cirurgia , Patela/diagnóstico por imagem , Radiografia/métodos , Resultado do Tratamento , Fraturas Cominutivas/diagnóstico por imagem , Procedimentos Ortopédicos
7.
Rev. chil. ortop. traumatol ; 62(2): 118-126, ago. 2021. ilus
Artigo em Espanhol | LILACS | ID: biblio-1413265

RESUMO

INTRODUCIÓN: La cirugía ambulatoria permite una reducción importante del costo en procedimientos de alta prevalencia; no obstante, siempre debe resguardarse la seguridad del paciente. OBJETIVO: Evaluar las complicaciones operatorias tempranas y resultados funcionales en pacientes sometidos a reconstrucción de ligamento cruzado anterior (R-LCA) en cirugía ambulatoria. Se analiza además una estimación en la reducción de costos por programa ambulatorio. MATERIAL Y MÉTODOS: Estudio retrospectivo de pacientes sometidos a R-LCA con técnica hueso-tendón-hueso (HTH) en pabellón ambulatorio en un mismo centro, entre 2016 y 2018. Se excluyeron pacientes con menos de un año de seguimiento. Se utilizó el mismo protocolo anestésico: anestesia espinal y bloqueo sensitivo único, asociado a analgesia postoperatoria por vía oral. Se entregó a pacientes instructivo de cuidados postoperatorios, síntomas de alarma, y ejercicios de fisioterapia al alta. Se realizó encuesta telefónica al tercer día para evaluar el estado general y las complicaciones, y, al final del seguimiento, para evaluación funcional mediante las escalas de Tegner y Lysholm pre- y postquirúrgicos. Se identificaronó a pacientes no dados de alta el mismo día, consulta precoz no programada, y reintervenciones. Se realizó un análisis de costo para evaluar el ahorro por procedimiento ambulatorio versus hospitalizado. RESULTADOS: Se operaron 36 pacientes de forma ambulatoria. En 4 (11,1%) se asoció a sutura meniscal con técnica dentro-fuera. La encuesta postoperatoria inicial fue respondida por 23 pacientes (63,8%); todos presentaron buen estado general: 43% sin dolor y 57% con molestias tolerables. No hubo sangrados. La encuesta al final del seguimiento (promedio: 22,5 7,9meses) fue respondida por 20 pacientes (55,5%): la puntación en las escalas de Tegner y Lysholm aumentó significativamente, de 3 (rango: 1 a 6) a 6 (rango: 3 a 8) (p » 0,0001) y de 44 (rango: 12 a 81) a 91 (rango: 61 a 100) (p » 0,0001), respectivamente. Todos fueron dados de alta el mismo día de la operación. Hubo 2 (5,5%) consultas precoces, una por caída en domicilio con dehiscencia de herida operatoria, y otra por hematoma no complicado. Se registraron dos reintervenciones: una dehiscencia de herida operatoria y una fractura de patela. La reducción de costos por realizar el procedimiento de forma ambulatoria fue de 203.205 pesos/paciente. CONCLUSIÓN: La cirugía ambulatoria de R-LCA mediante la técnica HTH fue un procedimiento seguro en esta serie, con un manejo adecuado del dolor y resultados funcionales satisfactorios al mediano plazo. Se asoció además a una reducción en estimación de costos.


INTRODUCTION: Outpatient procedures allow for an important cost reduction in highprevalence procedures; however, patient safety must always be ensured. OBJECTIVE: To evaluate the early complications and functional scores of patients undergoing an anterior cruciate ligament reconstruction (ACLR) as an outpatient procedure. An estimated cost reduction is also analyzed. MATERIALS AND METHODS: A retrospective study of patients undergoing outpatient ACLR with a bone-patellar tendon-bone (BPTB) technique in one center between 2016 and 2018. Patients with less than one year of follow-up were excluded. All patients were submitted to the same anesthetic protocol: spinal anesthesia, a one-shot echo-guided adductor canal nerve block, and outpatient analgesics. Upon discharge, all patients received instructions regarding postoperative care, physical therapy exercises, and red flags. A telephone survey was conducted on the third day to evaluate the general conditions and complications, as well at the final follow-up, to collect pre- and postoperative Tegner and Lysholm functional scores. Patients who were not discharged on the same day, early non-scheduled visits, and re-interventions were recorded. A cost-reduction analysis was performed for the inpatient versus outpatient procedures. RESULTS: In total, 36 patients were submitted to an outpatient procedure, and 4 (11.1%) had an outside-in meniscal suture. The survey was filled out by 23 patients (63.8%); all were in good general condition: 43% reported no pain and 57%, tolerable pain. No bleeding was observed. The survey at the end of the follow-up (average: 22.5 7.9 months) was filled out by 20 patients (55.5%); the scores on the Tegner and Lysholm scales improved significantly, from 3 (range: 1 to 6) to 6 (range: 3 to 8) (p » 0.0001), and from 44 (range: 12 to 81) to 91 (61 to 100) (p » 0.0001) respectively. All patients were discharged on the same day of surgery. There were 2 (5.5%) early visits, one due to a fall at home withdehiscence of the surgical wound, and one due to a non-complicated hematoma. Two re-interventions at the end of the follow-up were recorded: traumatic surgical-wound dehiscence and a patellar fracture. The cost reduction for the outpatient procedure was of 203, 205 pesos per patient CONCLUSION: The outpatient ACLR with the BPTB technique was a safe procedure in the present series, with adequate pain management and satisfactory functional scores at the medium-term follow-up. It was also associated with a reduction in cost estimates.


Assuntos
Humanos , Masculino , Feminino , Adolescente , Adulto , Procedimentos Cirúrgicos Ambulatórios/métodos , Lesões do Ligamento Cruzado Anterior/cirurgia , Inquéritos e Questionários , Estudos Retrospectivos , Resultado do Tratamento , Lesões do Ligamento Cruzado Anterior/complicações , Análise de Custo-Efetividade
9.
J Am Acad Orthop Surg Glob Res Rev ; 4(7): e2000098, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32672723

RESUMO

INTRODUCTION: Validity and reproducibility of the clinician's eye (CE) to diagnose patella alta (PA) on a lateral knee radiography (radiograph) is unknown. METHODS: Cross-sectional study of 46 lateral knee x-rays. Three blind observers used CE, Insall-Salvati (IS), modified Insall-Salvati (mIS), and Caton-Deschamps (C-D) to determine patellar height. Sensitivity and specificity of each observer was compared with the musculoskeletal radiologist's C-D measurements. Intraobserver and interobserver agreement were assessed with intraclass correlation coefficient and Fleiss κ, respectively. Time needed to estimate patellar height for every method was recorded in seconds. Statistical differences between observers were calculated with a generalized estimating equation. Analysis of variance and post hoc Bonferroni test compared duration of each method (P < 0.05). Data were analyzed using Stata 15 (StataCorp). RESULTS: CE, IS, mIS, and C-D's sensitivity and specificity values are as follows: 77%, 92%; 94%, 52%; 67%, 58%; and 53%, 89%, respectively. Intraclass correlation coefficient and Fleiss κ of CE, IS, mIS, and C-D values are as follows: 0.66 and 0.43, 0.88 and 0.68, 0.54 and 0.09, and 0.68 and 0.59, respectively. CE was the second most sensitive and most specific method for diagnosis of PA, with moderate intraobserver and interobserver agreement. IS was the most sensitive method with good intraobserver and interobserver agreement. CE was significantly faster (P < 0.05) than all other conventional radiographic ratios. CONCLUSION: CE's sensitivity increases with observer's experience and is highly specific. If normal patellar height is diagnosed, no other ratios are necessary, even in the less experienced clinician. Intraobserver and interobserver reproducibilities were moderate and only inferior to the IS ratio. In case patellar height is uncertain with the CE, the IS ratio is the most sensitive and reproducible method to confirm the diagnosis of PA.


Assuntos
Patela , Estudos Transversais , Patela/diagnóstico por imagem , Radiografia , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
10.
Sensors (Basel) ; 20(7)2020 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-32252481

RESUMO

This work proposes dedicated hardware for an intelligent control system on Field Programmable Gate Array (FPGA). The intelligent system is represented as Takagi-Sugeno Fuzzy-PI controller. The implementation uses a fully parallel strategy associated with a hybrid bit format scheme (fixed-point and floating-point). Two hardware designs are proposed; the first one uses a single clock cycle processing architecture, and the other uses a pipeline scheme. The bit accuracy was tested by simulation with a nonlinear control system of a robotic manipulator. The area, throughput, and dynamic power consumption of the implemented hardware are used to validate and compare the results of this proposal. The results achieved allow the use of the proposed hardware in applications with high-throughput, low-power and ultra-low-latency requirements such as teleoperation of robot manipulators, tactile internet, or industry 4.0 automation, among others.

11.
Sensors (Basel) ; 19(14)2019 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-31330949

RESUMO

The acquisition is the most time-consuming step performed by a Global Navigation Satellite System (GNSS) receiver. The objective is to detect which satellites are transmitting and what are the phase and Doppler frequency shift of the signal. It is the step with the highest computational complexity, especially for signals subjected to large Doppler shifts. Improving acquisition performance has a large impact on the overall performance of the GNSS reception. In this paper, we present a two-step Global Positioning System (GPS) acquisition algorithm whose first step performs an incremental correlation to find a coarse pair of phase and frequency and the second step, triggered by the variance of the largest correlation values, refines the first step. The proposed strategy, based on the conventional time-domain serial algorithm, reduces the average execution time of the acquisition process to about 1/5 of the conventional acquisition while keeping the same modest logic hardware requirements and slightly better success and false-positive rates. Additionally, the new method reduces memory usage by a factor that is proportional to the signal's sampling frequency. All these advantages over conventional acquisition contribute together to significantly improve the overall performance and cost of GPS receivers.

12.
Parasit Vectors ; 12(1): 374, 2019 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-31358033

RESUMO

BACKGROUND: Malaria remains an important public health problem in Peru where incidence has been increasing since 2011. Of over 55,000 cases reported in 2017, Plasmodium vivax was the predominant species (76%), with P. falciparum responsible for the remaining 24%. Nyssorhynchus darlingi (previously Anopheles darlingi) is the main vector in Amazonian Peru, where hyperendemic Plasmodium transmission pockets have been found. Mazán district has pronounced spatial heterogeneity of P. vivax malaria. However, little is known about behavior, ecology or seasonal dynamics of Ny. darlingi in Mazán. This study aimed to gather baseline information about bionomics of malaria vectors and transmission risk factors in a hyperendemic malaria area of Amazonian Peru. METHODS: To assess vector biology metrics, five surveys (two in the dry and three in the rainy season), including collection of sociodemographic information, were conducted in four communities in 2016-2017 on the Napo (Urco Miraño, URC; Salvador, SAL) and Mazán Rivers (Visto Bueno, VIB; Libertad, LIB). Human-biting rate (HBR), entomological inoculation rate (EIR) and human blood index (HBI) were measured to test the hypothesis of differences in entomological indices of Ny. darlingi between watersheds. A generalized linear mixed effect model (GLMM) was constructed to model the relationship between household risk factors and the EIR. RESULTS: Nyssorhynchus darlingi comprised 95% of 7117 Anophelinae collected and its abundance was significantly higher along the Mazán River. The highest EIRs (3.03-4.54) were detected in March and June in URC, LIB and VIB, and significantly more Ny. darlingi were infected outdoors than indoors. Multivariate analysis indicated that the EIR was >12 times higher in URC compared with SAL. The HBI ranged from 0.42-0.75; humans were the most common blood source, followed by Galliformes and cows. There were dramatic differences in peak biting time and malaria incidence with similar bednet coverage in the villages. CONCLUSIONS: Nyssorhynchus darlingi is the predominant contributor to malaria transmission in the Mazán District, Peru. Malaria risk in these villages is higher in the peridomestic area, with pronounced heterogeneities between and within villages on the Mazán and the Napo Rivers. Spatiotemporal identification and quantification of the prevailing malaria transmission would provide new evidence to orient specific control measures for vulnerable or at high risk populations.


Assuntos
Anopheles/fisiologia , Anopheles/parasitologia , Habitação , Malária/transmissão , Mosquitos Vetores/parasitologia , Rios , Adolescente , Adulto , Animais , Mordeduras e Picadas , Criança , Pré-Escolar , Feminino , Humanos , Incidência , Malária/epidemiologia , Malária Falciparum/epidemiologia , Malária Falciparum/transmissão , Malária Vivax/epidemiologia , Malária Vivax/transmissão , Masculino , Peru/epidemiologia , Fatores de Risco , Estações do Ano , Adulto Jovem
13.
PLoS One ; 13(10): e0204681, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30304006

RESUMO

The purpose of this work is to estimate the costs associated with managing patients with MS in Panama and evaluating the impact of the disease on their health-related quality of life (HRQoL). Multicentric observational, retrospective, cross-sectional study. The costs were estimated from societal and patient perspectives and expressed in USD, 2015. The focus of the study is based on prevalence and on a "bottom-up" approach. To estimate the total cost per patient, annual reported use for each resource was multiplied by its unit cost. To evaluate HRQoL, patients completed the EQ-5D-3L questionnaire. 108 patients took part in the study. 82.41% were women with 44.78 (SD: 12.27) years. 61.11% presented mild (EDSS = 0-3.5), 25.93% moderate (EDSS = 3.5-6) and 12.96%, severe disability (EDSS≥6.5). The mean annual cost from the patient's perspective was estimated at 777.99 USD (SD: 1,741.45) per patient. The mean cost from a societal perspective was estimated at 23,803.21 USD (SD: 13,331.83) per patient. Disease-modifying therapies (DMT) accounted for the main component of the cost. A deterioration in HRQoL was observed as the disease advances and as disability increases, with mobility and usual activities being the areas most affected by its progression. From both perspective, the cost per MS patient in Panama is high. In addition to the high economic impact, MS also exerts a negative impact on patient HRQoL, which increases as the disease advances.


Assuntos
Efeitos Psicossociais da Doença , Esclerose Múltipla/economia , Adulto , Estudos Transversais , Progressão da Doença , Feminino , Custos de Cuidados de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/epidemiologia , Esclerose Múltipla/terapia , Panamá/epidemiologia , Qualidade de Vida , Estudos Retrospectivos , Inquéritos e Questionários
14.
J Orthop Trauma ; 31(9): e288-e294, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28538287

RESUMO

BACKGROUND: To establish, from the health system perspective, the cost-utility relationship of limb reconstruction compared with primary amputation for patients older than 32 years with grade IIIB and IIIC severe lower limb trauma in Colombia, S.A. METHODS: A Markov model was built including different short-term and long-term states that represent the main events that a patient could experience after a lower limb amputation or a reconstruction. A 42-year time horizon was considered for the base case. Transition probabilities were obtained from a systematic review of the clinical literature. The health outcome selected was the quality-adjusted life years. Costs were determined by expert consensus using the standard case methodology, and valuation of resources was conducted with national-level pricing manuals. Deterministic sensitivity, scenarios, and probabilistic analyses were conducted. RESULTS: In the base case, the reconstruction of the limb compared with primary amputation was a dominant strategy; that is, reconstruction provides more quality-adjusted life years at a lower cost. This result changed only when the time horizon was less than 6 years or when the probability of a secondary amputation was >65%. CONCLUSIONS: Limb reconstruction is a dominant strategy compared with primary amputation, which is a conclusion that holds in most scenarios this study examined. Therefore, it should be considered in patients who, according to the clinical criteria and the severity and characteristics of their trauma, can benefit from this technique. LEVEL OF EVIDENCE: Economic Level II. See Instructions for Authors for a complete description of levels of evidence.


Assuntos
Amputação Cirúrgica/economia , Análise Custo-Benefício/métodos , Traumatismos da Perna/cirurgia , Procedimentos de Cirurgia Plástica/economia , Amputação Cirúrgica/métodos , Amputação Cirúrgica/estatística & dados numéricos , Colômbia , Feminino , Seguimentos , Humanos , Escala de Gravidade do Ferimento , Traumatismos da Perna/diagnóstico , Masculino , Cadeias de Markov , Procedimentos de Cirurgia Plástica/métodos , Procedimentos de Cirurgia Plástica/estatística & dados numéricos , Medição de Risco , Resultado do Tratamento , Cicatrização/fisiologia
15.
Ann Vasc Surg ; 40: 327-334, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27903479

RESUMO

BACKGROUND: The use of a prophylactic antibiotic in an amputation surgery is a key element for the successful recovery of the patient. We aim to determine, from the perspective of the Colombian health system, the cost-effectiveness of administering a prophylactic antibiotic among patients undergoing lower limb amputation due to diabetes or vascular illness in Colombia. METHODS: A decision tree was constructed to compare the use and nonuse of a prophylactic antibiotic. The probabilities of transition were obtained from studies identified from a systematic review of the clinical literature. The chosen health outcome was reduction in mortality due to prevention of infection. The costs were measured by expert consensus using the standard case methodology, and the resource valuation was carried out using national-level pricing manuals. Deterministic sensitivity, scenarios, and probabilistic analyses were conducted. RESULTS: In the base case, the use of a prophylactic antibiotic compared with nonuse was a dominant strategy. This result was consistent when considering different types of medications and when modifying most of the variables in the model. The use of a prophylactic antibiotic ceases to be dominant when the probability of infection is greater than 48%. CONCLUSIONS: The administration of a prophylactic antibiotic was a dominant strategy, which is a conclusion that holds in most cases examined; therefore, it is unlikely that the uncertainty around the estimation of costs and benefits change the results. We recommend creating policies oriented toward promoting the use of a prophylactic antibiotic during amputation surgery in Colombia.


Assuntos
Amputação Cirúrgica/economia , Antibacterianos/administração & dosagem , Antibacterianos/economia , Antibioticoprofilaxia/economia , Angiopatias Diabéticas/economia , Angiopatias Diabéticas/cirurgia , Custos de Medicamentos , Extremidade Inferior/irrigação sanguínea , Doenças Vasculares Periféricas/economia , Doenças Vasculares Periféricas/cirurgia , Infecção da Ferida Cirúrgica/economia , Infecção da Ferida Cirúrgica/prevenção & controle , Amputação Cirúrgica/efeitos adversos , Amputação Cirúrgica/mortalidade , Colômbia , Análise Custo-Benefício , Técnicas de Apoio para a Decisão , Árvores de Decisões , Angiopatias Diabéticas/diagnóstico , Angiopatias Diabéticas/mortalidade , Esquema de Medicação , Humanos , Modelos Econômicos , Doenças Vasculares Periféricas/diagnóstico , Doenças Vasculares Periféricas/mortalidade , Infecção da Ferida Cirúrgica/microbiologia , Resultado do Tratamento
16.
J Biol Chem ; 289(52): 36150-7, 2014 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-25384983

RESUMO

Hemichannels (HCs) are hexamers of connexins that can form gap-junction channels at points of cell contacts or "free HCs" at non-contacting regions. HCs are involved in paracrine and autocrine cell signaling, and under pathological conditions may induce and/or accelerate cell death. Therefore, studies of HC regulation are of great significance. Nitric oxide affects the activity of Cx43 and Cx46 HCs, whereas carbon monoxide (CO), another gaseous transmitter, modulates the activity of several ion channels, but its effect on HCs has not been explored. We studied the effect of CO donors (CORMs) on Cx46 HCs expressed in Xenopus laevis oocytes using two-electrode voltage clamp and on Cx43 and Cx46 expressed in HeLa cells using a dye-uptake technique. CORM-2 inhibited Cx46 HC currents in a concentration-dependent manner. The C-terminal domain and intracellular Cys were not necessary for the inhibition. The effect of CORM-2 was not prevented by guanylyl-cyclase, protein kinase G, or thioredoxin inhibitors, and was not due to endocytosis of HCs. However, the effect of CORM-2 was reversed by reducing agents that act extracellularly. Additionally, CO inhibited dye uptake of HeLa cells expressing Cx43 or Cx46, and MCF-7 cells, which endogenously express Cx43 and Cx46. Because CORM-2 carbonylates Cx46 in vitro and induces conformational changes, a direct effect of that CO on Cx46 is possible. The inhibition of HCs could help to understand some of the biological actions of CO in physiological and pathological conditions.


Assuntos
Monóxido de Carbono/farmacologia , Conexina 43/antagonistas & inibidores , Conexinas/antagonistas & inibidores , Compostos Organometálicos/farmacologia , Animais , Conexina 43/metabolismo , Conexinas/metabolismo , Glutationa/farmacologia , Células HeLa , Humanos , Células MCF-7 , Potenciais da Membrana , Carbonilação Proteica , Substâncias Redutoras/farmacologia , Xenopus laevis
17.
Rev Chilena Infectol ; 31(4): 473-6, 2014 Aug.
Artigo em Espanhol | MEDLINE | ID: mdl-25327203

RESUMO

Infection is the most serious complication of arthroplasty. It's a rare event usually caused by Staphylococcus spp. Prosthetic tuberculosis is rarely reported. We report the case of a 41 year-old patient who underwent a hip replacement for osteoarthritis and after multiple procedures an infection caused by Mycobacterium tuberculosis was documented. We review the literature of previously reported cases.


Assuntos
Prótese de Quadril/efeitos adversos , Infecções Relacionadas à Prótese/diagnóstico , Tuberculose Osteoarticular/diagnóstico , Adulto , Feminino , Humanos , Mycobacterium tuberculosis/isolamento & purificação , Infecções Relacionadas à Prótese/microbiologia
18.
Rev. chil. infectol ; 31(4): 473-476, ago. 2014. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-724818

RESUMO

Infection is the most serious complication of arthroplasty. It's a rare event usually caused by Staphylococcus spp. Prosthetic tuberculosis is rarely reported. We report the case of a 41 year-old patient who underwent a hip replacement for osteoarthritis and after multiple procedures an infection caused by Mycobacterium tuberculosis was documented. We review the literature of previously reported cases.


La infección es la complicación más seria de una artroplastia. Es un evento poco frecuente, usualmente causado por especies de Staphylococcus. La tuberculosis protésica es una entidad poco habitual. Comunicamos el caso de una paciente de 41 años sometida a un reemplazo de cadera por una artrosis y después de múltiples procedimientos se documentó una infección por Mycobacterium tuberculosis. Realizamos una revisión de la literatura de los casos previamente reportados.


Assuntos
Adulto , Feminino , Humanos , Prótese de Quadril/efeitos adversos , Infecções Relacionadas à Prótese/diagnóstico , Tuberculose Osteoarticular/diagnóstico , Mycobacterium tuberculosis/isolamento & purificação , Infecções Relacionadas à Prótese/microbiologia
19.
IEEE J Biomed Health Inform ; 17(3): 699-707, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-24592470

RESUMO

The development of a system for the automatic, objective, and reliable detection of cough events is a need underlined by the medical literature for years. The benefit of such a tool is clear as it would allow the assessment of pathology severity in chronic cough diseases. Even though some approaches have recently reported solutions achieving this task with a relative success, there is still no standardization about the method to adopt or the sensors to use. The goal of this paper is to study objectively the performance of several sensors for cough detection: ECG, thermistor, chest belt, accelerometer, contact, and audio microphones. Experiments are carried out on a database of 32 healthy subjects producing, in a confined room and in three situations, voluntary cough at various volumes as well as other event categories which can possibly lead to some detection errors: background noise, forced expiration, throat clearing, speech, and laugh. The relevance of each sensor is evaluated at three stages: mutual information conveyed by the features, ability to discriminate at the frame level cough from these latter other sources of ambiguity, and ability to detect cough events. In this latter experiment, with both an averaged sensitivity and specificity of about 94.5%, the proposed approach is shown to clearly outperform the commercial Karmelsonix system which achieved a specificity of 95.3% and a sensitivity of 64.9%.


Assuntos
Tosse/diagnóstico , Monitorização Fisiológica/métodos , Processamento de Sinais Assistido por Computador , Acelerometria/métodos , Adulto , Tosse/fisiopatologia , Fibrose Cística/fisiopatologia , Bases de Dados Factuais , Eletrocardiografia/métodos , Feminino , Humanos , Masculino , Redes Neurais de Computação , Sensibilidade e Especificidade , Espectrografia do Som/métodos , Adulto Jovem
20.
Conserv Biol ; 20(4): 1203-11, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16922236

RESUMO

Beta diversity, or the turnover in species composition among sampling sites in a region, is an important criterion for obtaining adequate representation of regional biodiversity in systems of protected areas. Recently, the additive model for partitioning regional (gamma) diversity (in opposition to the multiplicative model) has been proposed because it allows a direct measure of the contribution of beta diversity to gamma diversity. We determined avian beta diversity along latitudinal (among neighboring river drainages) and elevational axes in a 1347-km2 region on the western slope of the Central Cordillera of the Colombian Andes, where a regional system of protected areas is being designed. We then compared avian beta diversity between sites based on rapid versus long-term (>1 year) inventories and between fragmented sites versus continuous forest. Overall, beta diversity represented 63.1% of gamma diversity among 16 sites. Elevational differences in species composition accounted for 43.3% of regional diversity, whereas differences among drainages accounted for 19.8%. A complementary cluster analysis showed that sites grouped by elevational zones. Rapid inventories overestimated beta diversity because of sampling effects, but the effect was biologically small. Estimators of species richness derived from species accumulation curves provided a useful alternative to compensate for undersampling in short-term surveys. Forest fragmentation increased beta diversity because of differential local extinction of populations. Nevertheless, in our region, forest fragments contributed to gamma diversity because they contained complementary sets of species. More importantly, they contained populations of special-interest species. Although the region is relatively small, our analyses indicate that spatial differentiation of the biota is an important factor for deciding number and location of protected areas in the Andean region.


Assuntos
Biodiversidade , Aves/classificação , Conservação dos Recursos Naturais/métodos , Geografia , Animais , Aves/fisiologia , Análise por Conglomerados , Colômbia , Dinâmica Populacional , Árvores
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