Papers by jose perdomo perez
Risk factors for nonunion following tibiotalocalcaneal arthrodesis: A systematic review and meta-analysis
Foot and Ankle Surgery, 2022
Category: Ankle; Ankle Arthritis; Trauma Introduction/Purpose: Tibiotalocalcaneal (TTC) arthrodes... more Category: Ankle; Ankle Arthritis; Trauma Introduction/Purpose: Tibiotalocalcaneal (TTC) arthrodesis is a routinely utilized salvage procedure that treats patients with severe talar and subtalar joint disease. Unfortunately, nonunion is a relatively common complication postoperatively which can increase risks and costs for patients. The goal of this study is to review the literature to identify risk factors for nonunion post TTC arthrodesis and stratify them based on strength of evidence. A meta-analysis will be performed on risk factors when appropriate to establish values based on pre-existing studies. Methods: Five databases (CINAHL, Cochrane Library, EMBASE, MEDLINE, and Web of Science) were searched from inception to May 17th, 2020. Two independent reviewers screened abstracts and full-text articles for those that included risk factors predictive of nonunion for TTC arthrodesis. Any disagreements were discussed between the two reviewers and a third reviewer served as the ultimate decision maker if a consensus could not be reached. Relevant data regarding participants’ characteristics, study design, follow-up time, statistical tests and identified risk factors were extracted from the included studies. The two reviewers independently appraised the methodological quality of the studies using the Quality In Prognosis Studies tool. Those risk factors described in multiple studies were included in the meta-analysis. Random effects meta-analyses were summarized as forest plots of individual study and pooled random effect results. Results were reported as odds ratios (OR) with 95% confidence intervals (CI). Results: Database search identified 428 articles, of which 113 were screened for full text. Eight studies involving 607 patients were included and 33 potential risk factors for nonunion were identified. Risk factors were stratified into demographic, preoperative, intraoperative and postoperative. Results of the meta-analysis established two significant risk factors for nonunion following TTC arthrodesis. Strong evidence supports that prior neurological deficits, such as Charcot neuroarthropathy and diabetes neuropathy, are associated with nonunion following surgery (OR: 2.86, 95% CI: 1.56 - 5.23). There was moderate evidence to suggest that preoperative infection was predictive for nonunion (OR: 3.99, 95% CI: 1.26 - 12.68). Although our meta- analysis did not find smoking (OR: 1.75, 95% CI: 0.90 - 3.38) or diabetes (OR: 2.28, 95% CI: 0.98 - 5.34) to be significant risk factors, multiple high quality studies support these as comorbidities that increase the likelihood of nonunion. Conclusion: TTC arthrodesis can be an effective salvage procedure but is associated with high nonunion rates. The results of our meta-analysis suggest that prior neurological deficits, such as Charcot neuroarthropathy or diabetes neuropathy, have strong evidence for failure to achieve union. Although our meta-analysis did not find other statistically significant risk factors, the findings of individual studies in our review suggest that diabetes mellitus and smoking are both factors which can lead to failure of fusion. Surgeons should be cognizant of these risks when performing TTC arthrodesis and carefully monitor patients with the aforementioned comorbidities to achieve successful results.
2010 IEEE Electronics, Robotics and Automotive Mechanics Conference, 2010
In this paper the problem of trajectory tracking is studied. Based on the Lyapunov theory, a cont... more In this paper the problem of trajectory tracking is studied. Based on the Lyapunov theory, a control law that achieves the global asymptotic stability of the tracking error between a recurrent neural network and a complex dynamical network is obtained. To illustrate the analytic results we present a tracking simulation of a dynamical network with each node being just one Lorenz´s dynamical system and three identical Chen's dynamical systems.
Chaos synchronization via adaptive recurrent neural control
Proceedings of the 40th IEEE Conference on Decision and Control (Cat. No.01CH37228)
This paper proposes a new adaptive control structure, based on a dynamic neural network, for traj... more This paper proposes a new adaptive control structure, based on a dynamic neural network, for trajectory tracking of unknown nonlinear plants. The main components of this structure include a neural identifier and a control law, which together guarantee the desired trajectory tracking performance. Stability of the tracking control is analyzed by using the Lyapunov function method, and the structure is tested by simulations on an example of complex dynamical systems: chaos synchronization
IEEE Latin America Transactions, 2012
This paper describes the study about parking spaces detection in indoor environments, implementin... more This paper describes the study about parking spaces detection in indoor environments, implementing a WSN (Wireless Sensor Network) based on ZigBee technology. Our study focuses on the analysis of the received power when a vehicle is parked or not, by monitoring the RSSI (Received Signal Strength Indicator) field defined in the MAC layer as the IEEE 802.15.4 describes. We focus in the analysis of three factors: data processing time, the influence of distance in received power and the attenuation effect in the signal when propagates, which determine the network topology to deploy and the validity of our location model.
Journal of Graduate Medical Education, 2009
Completion of an outline of a PDSA project to be conducted in the PCC Compensation Plans Analysis... more Completion of an outline of a PDSA project to be conducted in the PCC Compensation Plans Analysis of a mock offer of physician compensation Wrap-Up and Post-Modules Survey
Lecture Notes in Control and Information Sciences, 2004
This chapter presents an application of neural networks to chaos synchronization. The two main me... more This chapter presents an application of neural networks to chaos synchronization. The two main methodologies, on which the approach is based, are recurrent neural networks and inverse optimal control for nonlinear systems. On the basis of the last technique, chaos is first produced by a stable recurrent neural network; an adaptive recurrent neural controller is then developed for chaos synchronization.
Pharmacy Practice (Internet), 2007
Only one study evaluated the scientific activity in community pharmacies in Spain, and it was res... more Only one study evaluated the scientific activity in community pharmacies in Spain, and it was restricted to articles published in just two journals. Objective: To assess the scientific activity in community pharmacies in Spain through a bibliometric analysis of the original papers published during the years 1995-2005. Methods: IPA, MEDLINE, CSIC database and the journals Seguimiento Farmacoterapéutico y Pharmaceutical Care España were used as data sources. Production indicators, consumption indicators and the impact factor (IF) as a repercussion index were analyzed. Results: 122 articles were included in the review. The articles were published in 12 journals, 78.7% of them in Pharmaceutical Care España and Seguimiento Farmacoterapéutico. The mean number of authors per article was 4.2 (SD=2.1). The transitivity index was 71.3%. The total number of references cited in the articles was 2110. The mean number of references per article was 17.3 SD=9.3. The value of the insularity index was 57.6%. Self citation was 6.8% and the Price index was 66.5%. No impact factor was available for 6 journals. Conclusions: Publication of articles on community pharmacy-based research in Spain has undergone an important increase in the last 5 years. The existence of authors who publish very few studies, the high insularity index and the lack of randomized, controlled trials may be considered as negative indicators in community pharmacy-based research in Spain.
Journal of the American Society of Nephrology, 2006
Calcimimetics decrease parathyroid hormone (PTH) levels in uremic patients with secondary hyperpa... more Calcimimetics decrease parathyroid hormone (PTH) levels in uremic patients with secondary hyperparathyroidism without increasing serum calcium (Ca). The aim of this study was to evaluate the effect of calcimimetic R-568 alone or in combination with calcitriol on vascular and other soft tissue calcifications in uremic rats with secondary hyperparathyroidism. Shamoperated and 5/6 nephrectomized Wistar rats were studied. 5/6 Nephrectomized rats were treated with vehicle, calcitriol (80 ng/kg every other day), R-568 (1.5 and 3 mg/kg per d), and both calcitriol and R-568 1.5 mg/kg, as above. Rats were killed after 14 or 56 d of treatment. Blood was drawn for biochemical measurements. Aortic, heart, kidney, lung, and stomach tissue samples were processed for histopathology and measurement of tissue Ca and phosphorus content. PTH concentrations were significantly reduced by all treatments. Treatment with calcitriol induced significant vascular calcification (aortic Ca increased to 4.2 ؎ 1.2 mg/g at day 14 and to 11.4 ؎ 0.7 mg/g at day 56; P < 0.05 versus vehicle). Treatment with R-568 did not induce vascular calcification. Concurrent administration of R-568 with calcitriol reduced the aortic Ca (1.9 ؎ 0.2 mg/g at day 14 and 7.5 ؎ 1.4 mg/g at day 56) in relation to calcitriol alone. Soft tissue calcifications mirrored aortic mineralizations. Survival was significantly (P < 0.001) reduced in calcitriol-treated rats, and mortality was attenuated (P ؍ 0.01) by concurrent treatment with R-568. In uremic rats, R-568 reduces elevated PTH levels without inducing vascular calcification, prevents calcitriol-induced vascular calcification, and decreases mortality.
IEEE Transactions on Neural Networks, 1999
In this paper the adaptive nonlinear identification and trajectory tracking are discussed via dyn... more In this paper the adaptive nonlinear identification and trajectory tracking are discussed via dynamic neural networks. By means of a Lyapunov-like analysis we determine stability conditions for the identification error. Then we analyze the trajectory tracking error by a local optimal controller. An algebraic Riccati equation and a differential one are used for the identification and the tracking error analysis. As our main original contributions, we establish two theorems: the first one gives a bound for the identification error and the second one establishes a bound for the tracking error. We illustrate the effectiveness of these results by two examples: the second-order relay system with multiple isolated equilibrium points and the chaotic system given by Duffing equation.
BMC Plant Biology, 2008
Background: The elucidation of gene expression patterns leads to a better understanding of biolog... more Background: The elucidation of gene expression patterns leads to a better understanding of biological processes. Real-time quantitative RT-PCR has become the standard method for in-depth studies of gene expression. A biologically meaningful reporting of target mRNA quantities requires accurate and reliable normalization in order to identify real gene-specific variation. The purpose of normalization is to control several variables such as different amounts and quality of starting material, variable enzymatic efficiencies of retrotranscription from RNA to cDNA, or differences between tissues or cells in overall transcriptional activity. The validity of a housekeeping gene as endogenous control relies on the stability of its expression level across the sample panel being analysed. In the present report we describe the first systematic evaluation of potential internal controls during tomato development process to identify which are the most reliable for transcript quantification by real-time RT-PCR. Results: In this study, we assess the expression stability of 7 traditional and 4 novel housekeeping genes in a set of 27 samples representing different tissues and organs of tomato plants at different developmental stages. First, we designed, tested and optimized amplification primers for real-time RT-PCR. Then, expression data from each candidate gene were evaluated with three complementary approaches based on different statistical procedures. Our analysis suggests that SGN-U314153 (CAC), SGN-U321250 (TIP41), SGN-U346908 ("Expressed") and SGN-U316474 (SAND) genes provide superior transcript normalization in tomato development studies. We recommend different combinations of these exceptionally stable housekeeping genes for suited normalization of different developmental series, including the complete tomato development process. Conclusion: This work constitutes the first effort for the selection of optimal endogenous controls for quantitative real-time RT-PCR studies of gene expression during tomato development process. From our study a tool-kit of control genes emerges that outperform the traditional genes in terms of expression stability.
Aquaculture Research, 1994
Two experiments were carried out to study the effect of «-3 HUFA levels in rotifers on survival, ... more Two experiments were carried out to study the effect of «-3 HUFA levels in rotifers on survival, growth, activity and fatty acid composition of gilthead bream, Sparus aurata (L.), larvae. From the third to the 15th day after hatching, gilthead bream larvae received one of the three kinds of rotifers containing different percentages of n-3 HUFA. Moisture, crude lipid, saponifiable matter and fatty acid composition of total lipids of rotifers and larvae were determined. A good correlation was found between larval growth and n-3 HUFA levels in rotifers. Larval survival was also significantly improved by the elevation of the n-3 HUFA levels in rotifers. A high occurrence of hydrops was registered in larvae fed with EFA-deficient rotifers. The n-3 HUFA levels in the larvae were increased by the elevation of n-3 HUFA contents in rotifers. However, n-9 fatty acids in the larvae remained almost constant, regardless of the different 18:1 n-9 contents in rotifers. Therefore, the ratio of oleic acid to n-3 HUFA, known to be an indicator of the EFA deficiency in fish, was reduced by the elevation of the n-3 HUFA levels in rotifers.
Algunas claves sociopolíticas para la interpretación de las elecciones municipales de 10 de junio de 1987 en el marco de la evolución electoral andaluza
Revista de estudios …, 1989
... se puede observar en el siguiente cuadro de evolución de la partici-pación electoral en Andal... more ... se puede observar en el siguiente cuadro de evolución de la partici-pación electoral en Andalucía, las mayores bolsas de abstencionismo ... en general, la política ambigua de chalaneo y pactos a destiempo tremenda-mente personalista, de su líder Rojas Marcos, quien ofrecía ...
Anales de Medicina Interna, 2001
El absceso hepático piógeno es una enfermedad que, históricamente, ha sido considerada de diagnós... more El absceso hepático piógeno es una enfermedad que, históricamente, ha sido considerada de diagnóstico dificultoso y manejo terapéutico complicado, asociándose a elevada mortalidad (1). En las últimas décadas, a pesar de los avances antibioticoterápicos y de la introducción de técnicas radiológicas, como la ecografía y la TAC, que permitieron el desarrollo de técnicas conservadoras, la tasa de mortalidad en pacientes quirúrgicos y en los tratados mediante drenaje percutáneo, aún se sitúa entre 12-26 y 2-15%, respectivamente (2-5). Estos no tan favorables resultados se atribuyen al incremento en el número de pacientes con neoplasias, patología biliar compleja, edad avanzada y estados de inmunosupresión postquimioterapia.
Acta Crystallographica Section B Structural Science, 2005
Two methods for the classification of eight-membered rings based on a Bayesian analysis are prese... more Two methods for the classification of eight-membered rings based on a Bayesian analysis are presented. The two methods share the same probabilistic model for the measurement of torsion angles, but while the first method uses the canonical forms of cyclooctane and, given an empirical sequence of eight torsion angles, yields the probability that the associated structure corresponds to each of the ten canonical conformations, the second method does not assume previous knowledge of existing conformations and yields a clustering classification of a data set, allowing new conformations to be detected. Both methods have been tested using the conformational classification of Csp 3 eight-membered rings described in the literature. The methods have also been employed to classify the solid-state conformation in Csp 3 eight-membered rings using data retrieved from an updated version of the Cambridge Structural Database (CSD).
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Papers by jose perdomo perez