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1.
Antimicrob Agents Chemother ; : e0012724, 2024 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-38995033

RESUMEN

The siderophore-cephalosporin cefiderocol (FDC) presents a promising treatment option for carbapenem-resistant (CR) P. aeruginosa (PA). FDC circumvents traditional porin and efflux-mediated resistance by utilizing TonB-dependent receptors (TBDRs) to access the periplasmic space. Emerging FDC resistance has been associated with loss of function mutations within TBDR genes or the regulatory genes controlling TBDR expression. Further, difficulties with antimicrobial susceptibility testing (AST) and unexpected negative clinical treatment outcomes have prompted concerns for heteroresistance, where a single lineage isolate contains resistant subpopulations not detectable by standard AST. This study aimed to evaluate the prevalence of TBDR mutations among clinical isolates of P. aeruginosa and the phenotypic effect on FDC susceptibility and heteroresistance. We evaluated the sequence of pirR, pirS, pirA, piuA, or piuD from 498 unique isolates collected before the introduction of FDC from four clinical sites in Portland, OR (1), Houston, TX (2), and Santiago, Chile (1). At some clinical sites, TBDR mutations were seen in up to 25% of isolates, and insertion, deletion, or frameshift mutations were predicted to impair protein function were seen in 3% of all isolates (n = 15). Using population analysis profile testing, we found that P. aeruginosa with major TBDR mutations were enriched for a heteroresistant phenotype and undergo a shift in the susceptibility distribution of the population as compared to susceptible strains with wild-type TBDR genes. Our results indicate that mutations in TBDR genes predate the clinical introduction of FDC, and these mutations may predispose to the emergence of FDC resistance.

2.
Heliyon ; 10(4): e26363, 2024 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-38420453

RESUMEN

A gains optimizer of a fuzzy controller system for an Unmanned Aerial Vehicle (UAV) based on a metaheuristic algorithm is developed in the present investigation. The contribution of the work is the adjustment by the Genetic Algorithm (GA) to tune the gains at the input of a fuzzy controller. First, a typical fuzzy controller was modeled, designed, and implemented in a mathematical model obtained by Newton-Euler methodology. Subsequently, the control gains were optimized using a metaheuristic algorithm. The control objective is that the UAV consumes the least amount of energy. With this basis, the Genetic Algorithm finds the necessary gains to meet the design parameters. The tests were performed using the Matlab-Simulink environment. The results indicate an improvement, reducing the error in tracking trajectories from 30% in some tasks and following trajectories that could not be completed without a tuned controller in other tasks.

3.
bioRxiv ; 2024 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-38352536

RESUMEN

The siderophore-cephalosporin cefiderocol(FDC) presents a promising treatment option for carbapenem-resistant (CR) P. aeruginosa (PA). FDC circumvents traditional porin and efflux mediated resistance by utilizing TonB-dependent receptors (TBDRs) to access the periplasmic space. Emerging FDC resistance has been associated with loss of function mutations within TBDR genes or the regulatory genes controlling TBDR expression. Further, difficulties with antimicrobial susceptibility testing (AST) and unexpected negative clinical treatment outcomes have prompted concerns for heteroresistance, where a single lineage isolate contains resistant subpopulations not detectable by standard AST. This study aimed to evaluate the prevalence of TBDR mutations among clinical isolates of P. aeruginosa and the phenotypic effect on FDC susceptibility and heteroresistance. We evaluated the sequence of pirR , pirS , pirA , piuA or piuD from 498 unique isolates collected before the introduction of FDC from 4 clinical sites in Portland, OR (1), Houston, TX (2), and Santiago, Chile (1). At some clinical sites, TBDR mutations were seen in up to 25% of isolates, and insertion, deletion, or frameshift mutations were predicted to impair protein function were seen in 3% of all isolates (n=15). Using population analysis profile testing, we found that P. aeruginosa with major TBDR mutations were enriched for a heteroresistant phenotype and undergo a shift in the susceptibility distribution of the population as compared to susceptible strains with wild type TBDR genes. Our results indicate that mutations in TBDR genes predate the clinical introduction of FDC, and these mutations may predispose to the emergence of FDC resistance.

4.
Hong Kong J Occup Ther ; 36(2): 128-140, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38027046

RESUMEN

Background/Objective: The use of new technologies in rehabilitation to evaluate and improve occupational performance and quality of life is increasing. Technological applications in the health field could help meet the needs of patients, including those of women breast cancer survivors. The main aim of this study was to design a mobile phone application "MAIA" focused on the perceived needs of women who have had breast cancer to achieve optimal performance in their daily lives in a meaningful way. Methods: A cross-sectional usability study using an online questionnaire was designed. Sociodemographic and occupational performance data were collected. System Usability Scale, Engagement in Meaningful Activities Survey, Occupational Balance Questionnaire, General Self-Efficacy Scale, Functional Assessment of Cancer Therapy - General and Disabilities of the Arm, Shoulder and Hand were administered. Descriptive statistics were used to describe categorical (frequencies and percentages) and quantitative variables (mean and standard deviation). Results: The sample was composed of seventy-eight women diagnosed with breast cancer. Nine activities of daily living were affected in more than 20% of women with breast cancer. The most affected were sleep and rest and functional mobility. Conclusions: Women survivors of breast cancer showed difficulties in daily life performance and participation. The MAIA App could be useful as a new online resource in occupational therapy for the rehabilitation of breast cancer survivors.

5.
Clin Infect Dis ; 77(Suppl 1): S20-S28, 2023 07 05.
Artículo en Inglés | MEDLINE | ID: mdl-37406053

RESUMEN

BACKGROUND: The impact of coronavirus disease 2019 (COVID-19) on antimicrobial use (AU) and resistance has not been well evaluated in South America. These data are critical to inform national policies and clinical care. METHODS: At a tertiary hospital in Santiago, Chile, between 2018 and 2022, subdivided into pre- (3/2018-2/2020) and post-COVID-19 onset (3/2020-2/2022), we evaluated intravenous AU and frequency of carbapenem-resistant Enterobacterales (CRE). We grouped monthly AU (defined daily doses [DDD]/1000 patient-days) into broad-spectrum ß-lactams, carbapenems, and colistin and used interrupted time-series analysis to compare AU during pre- and post-pandemic onset. We studied the frequency of carbapenemase-producing (CP) CRE and performed whole-genome sequencing analyses of all carbapenem-resistant (CR) Klebsiella pneumoniae (CRKpn) isolates collected during the study period. RESULTS: Compared with pre-pandemic, AU (DDD/1000 patient-days) significantly increased after the pandemic onset, from 78.1 to 142.5 (P < .001), 50.9 to 110.1 (P < .001), and 4.1 to 13.3 (P < .001) for broad-spectrum ß-lactams, carbapenems, and colistin, respectively. The frequency of CP-CRE increased from 12.8% pre-COVID-19 to 51.9% after pandemic onset (P < .001). The most frequent CRE species in both periods was CRKpn (79.5% and 76.5%, respectively). The expansion of CP-CRE harboring blaNDM was particularly noticeable, increasing from 40% (n = 4/10) before to 73.6% (n = 39/53) after pandemic onset (P < .001). Our phylogenomic analyses revealed the emergence of two distinct genomic lineages of CP-CRKpn: ST45, harboring blaNDM, and ST1161, which carried blaKPC. CONCLUSIONS: AU and the frequency of CP-CRE increased after COVID-19 onset. The increase in CP-CRKpn was driven by the emergence of novel genomic lineages. Our observations highlight the need to strengthen infection prevention and control and antimicrobial stewardship efforts.


Asunto(s)
Antiinfecciosos , COVID-19 , Enterobacteriaceae Resistentes a los Carbapenémicos , Humanos , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Klebsiella pneumoniae/genética , Chile/epidemiología , Colistina , Pacientes Internos , Filogenia , Pandemias , COVID-19/epidemiología , Proteínas Bacterianas/genética , beta-Lactamasas/genética , Carbapenémicos/farmacología , Carbapenémicos/uso terapéutico , Hospitales , beta-Lactamas , Pruebas de Sensibilidad Microbiana
6.
Microbiol Spectr ; 11(4): e0535122, 2023 08 17.
Artículo en Inglés | MEDLINE | ID: mdl-37338398

RESUMEN

The global dissemination of methicillin-resistant Staphylococcus aureus (MRSA) is associated with the emergence and establishment of clones in specific geographic areas. The Chilean-Cordobes clone (ChC) (ST5-SCCmecI) has been the predominant MRSA clone in Chile since its first description in 1998, despite the report of other emerging MRSA clones in recent years. Here, we characterize the evolutionary history of MRSA from 2000 to 2016 in a Chilean tertiary health care center using phylogenomic analyses. We sequenced 469 MRSA isolates collected between 2000 and 2016. We evaluated the temporal trends of the circulating clones and performed a phylogenomic reconstruction to characterize the clonal dynamics. We found a significant increase in the diversity and richness of sequence types (STs; Spearman r = 0.8748, P < 0.0001) with a Shannon diversity index increasing from 0.221 in the year 2000 to 1.33 in 2016, and an effective diversity (Hill number; q = 2) increasing from 1.12 to 2.71. The temporal trend analysis revealed that in the period 2000 to 2003 most of the isolates (94.2%; n = 98) belonged to the ChC clone. However, since then, the frequency of the ChC clone has decreased over time, accounting for 52% of the collection in the 2013 to 2016 period. This decline was accompanied by the rise of two emerging MRSA lineages, ST105-SCCmecII and ST72-SCCmecVI. In conclusion, the ChC clone remains the most frequent MRSA lineage, but this lineage is gradually being replaced by several emerging clones, the most important of which is clone ST105-SCCmecII. To the best of our knowledge, this is the largest study of MRSA clonal dynamics performed in South America. IMPORTANCE Methicillin-resistant Staphylococcus aureus (MRSA) is a major public health pathogen that disseminates through the emergence of successful dominant clones in specific geographic regions. Knowledge of the dissemination and molecular epidemiology of MRSA in Latin America is scarce and is largely based on small studies or more limited typing techniques that lack the resolution to represent an accurate description of the genomic landscape. We used whole-genome sequencing to study 469 MRSA isolates collected between 2000 and 2016 in Chile providing the largest and most detailed study of clonal dynamics of MRSA in South America to date. We found a significant increase in the diversity of MRSA clones circulating over the 17-year study period. Additionally, we describe the emergence of two novel clones (ST105-SCCmecII and ST72-SCCmecVI), which have been gradually increasing in frequency over time. Our results drastically improve our understanding of the dissemination and update our knowledge about MRSA in Latin America.


Asunto(s)
Staphylococcus aureus Resistente a Meticilina , Infecciones Estafilocócicas , Humanos , Staphylococcus aureus Resistente a Meticilina/genética , Infecciones Estafilocócicas/epidemiología , Chile/epidemiología , Filogenia , Centros de Atención Terciaria , Antibacterianos
7.
Front Microbiol ; 13: 1035609, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36353456

RESUMEN

Objectives: Identify molecular mechanisms responsible for the in vitro non-susceptibility to ceftolozane/tazobactam (TOL) in a group of 158 clinical isolates of Pseudomonas aeruginosa from five Latin American countries collected before the introduction of TOL into the clinical practice. Methods: Clinical isolates of P. aeruginosa (n = 504) were collected between January 2016 and October 2017 from 20 hospitals located in Argentina, Brazil, Chile, Colombia, and Mexico. Minimum inhibitory concentrations (MICs) to TOL were determined by standard broth microdilution and interpreted according to CLSI breakpoints. Initially, production of carbapenemases in TOL non-susceptible isolates was assessed by Rapidec® followed by qPCR to detect bla KPC, bla NDM-1, bla VIM, and bla IMP. Illumina® WGS was performed for isolates in which non-susceptibility to TOL was not mediated by carbapenemases. Results: A total of 158 (31.3%) isolates were non-susceptible to TOL. In 74 (46.8%) of these isolates, non-susceptibility to TOL was explained by the production of at least one carbapenemase. WGS revealed that some isolates carried ESBLs, mutated bla PDC and ampD, associated with decreased susceptibility to TOL. Conclusion: Substitutions found in PDC and carbapenemase production were the most common presumed mechanisms of resistance to TOL detected in this study. This study shows that epidemiological surveillance is warranted to monitor the emergence of novel mechanisms of resistance to TOL that might compromise its clinical utility.

8.
Front Pharmacol ; 13: 1007162, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36263116

RESUMEN

Carbapenem-resistant Pseudomonas aeruginosa (CRPA) is one of the pathogens that urgently needs new drugs and new alternatives for its control. The primary strategy to combat this bacterium is combining treatments of beta-lactam with a beta-lactamase inhibitor. The most used combinations against P. aeruginosa are ceftazidime/avibactam (CZA) and ceftolozane/tazobactam (C/T). Although mechanisms leading to CZA and C/T resistance have already been described, among which are the resistance-nodulation-division (RND) efflux pumps, the role that these extrusion systems may play in CZA, and C/T baseline susceptibility of clinical isolates remains unknown. For this purpose, 161 isolates of non-carbapenemase-producing (Non-CP) CRPA were selected, and susceptibility tests to CZA and C/T were performed in the presence and absence of the RND efflux pumps inhibitor, Phenylalanine-arginine ß-naphthylamide (PAßN). In the absence of PAßN, C/T showed markedly higher activity against Non-CP-CRPA isolates than observed for CZA. These results were even more evident in isolates classified as extremely-drug resistant (XDR) or with difficult-to-treat resistance (DTR), where CZA decreased its activity up to 55.2% and 20.0%, respectively, whereas C/T did it up to 82.8% (XDR), and 73.3% (DTR). The presence of PAßN showed an increase in both CZA (37.6%) and C/T (44.6%) activity, and 25.5% of Non-CP-CRPA isolates increased their susceptibility to these two combined antibiotics. However, statistical analysis showed that only the C/T susceptibility of Non-CP-CRPA isolates was significantly increased. Although the contribution of RND activity to CZA and C/T baseline susceptibility was generally low (two-fold decrease of minimal inhibitory concentrations [MIC]), a more evident contribution was observed in a non-minor proportion of the Non-CP-CRPA isolates affected by PAßN [CZA: 25.4% (15/59); C/T: 30% (21/70)]. These isolates presented significantly higher MIC values for C/T. Therefore, we conclude that RND efflux pumps are participating in the phenomenon of baseline susceptibility to CZA and, even more, to C/T. However, the genomic diversity of clinical isolates is so great that deeper analyzes are necessary to determine which elements are directly involved in this phenomenon.

9.
Front Cell Infect Microbiol ; 12: 981792, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36118031

RESUMEN

Ceftazidime/Avibactam (CAZ/AVI) is frequently used to treat KPC-producing Pseudomonas aeruginosa (KPC-PA) and Enterobacterales. CAZ/AVI resistance is driven by several mechanisms. In P. aeruginosa this mainly occurs through alteration of AmpC, porins, and/or efflux pump overexpression, whereas in Enterobacterales it frequently occurs through D179Y substitution in the active site of KPC enzyme. This aminoacid change abolishes AVI binding to the KPC active site, hence inhibition is impaired. However, this substitution also decreases KPC-mediated resistance to carbapenems ("see-saw" effect). The goal of this work was to characterize the in vivo acquisition of CAZ/AVI resistance through D179Y substitution in a KPC-PA isolated from a hospitalized patient after CAZ/AVI treatment. Two KPC-PA isolates were obtained. The first isolate, PA-1, was obtained before CAZ/AVI treatment and was susceptible to CAZ/AVI. The second isolate, PA-2, was obtained after CAZ/AVI treatment and exhibited high-level CAZ/AVI resistance. Characterization of isolates PA-1 and PA-2 was performed through short and long-read whole genome sequencing analysis. The hybrid assembly showed that PA-1 and PA-2A had a single plasmid of 54,030 bp, named pPA-1 and pPA-2 respectively. Each plasmid harbored two copies of the bla KPC-containing Tn4401b transposon. However, while pPA-1 carried two copies of bla KPC-2, pPA-2 had one copy of bla KPC-2 and one copy of bla KPC-33, the allele with the D179Y substitution. Interestingly, isolate PA-2 did not exhibit the "see-saw" effect. The bla KPC-33 allele was detected only through hybrid assembly using a long-read-first approach. The present work describes a KPC-PA isolate harboring a plasmid-borne CAZ/AVI resistance mechanism based on two copies of bla KPC-2-Tn4401b and D179Y mutation in one of them, that is not associated with loss of resistance to carbapenems. These findings highlight the usefulness of a fine-tuned combined analysis of short and long-read data to detect similar emerging resistance mechanisms.


Asunto(s)
Ceftazidima , Pseudomonas aeruginosa , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Compuestos de Azabiciclo , Carbapenémicos/farmacología , Ceftazidima/farmacología , Combinación de Medicamentos , Humanos , Pruebas de Sensibilidad Microbiana , Mutación , Porinas/genética , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/metabolismo , beta-Lactamasas/genética , beta-Lactamasas/metabolismo
10.
PLoS One ; 17(1): e0261853, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35025926

RESUMEN

Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) is used worldwide to test and trace the spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). "Extraction-less" or "direct" real time-reverse transcription polymerase chain reaction (RT-PCR) is a transparent and accessible qualitative method for SARS-CoV-2 detection from nasopharyngeal or oral pharyngeal samples with the potential to generate actionable data more quickly, at a lower cost, and with fewer experimental resources than full RT-qPCR. This study engaged 10 global testing sites, including laboratories currently experiencing testing limitations due to reagent or equipment shortages, in an international interlaboratory ring trial. Participating laboratories were provided a common protocol, common reagents, aliquots of identical pooled clinical samples, and purified nucleic acids and used their existing in-house equipment. We observed 100% concordance across laboratories in the correct identification of all positive and negative samples, with highly similar cycle threshold values. The test also performed well when applied to locally collected patient nasopharyngeal samples, provided the viral transport media did not contain charcoal or guanidine, both of which appeared to potently inhibit the RT-PCR reaction. Our results suggest that direct RT-PCR assay methods can be clearly translated across sites utilizing readily available equipment and expertise and are thus a feasible option for more efficient COVID-19 coronavirus disease testing as demanded by the continuing pandemic.


Asunto(s)
Prueba de COVID-19/métodos , COVID-19/diagnóstico , ARN Viral/genética , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Transcripción Reversa/genética , SARS-CoV-2/genética , COVID-19/virología , Estudios de Factibilidad , Humanos , Nasofaringe/virología , Pandemias/prevención & control , Sensibilidad y Especificidad , Pruebas Serológicas/métodos , Manejo de Especímenes/métodos
11.
Antimicrob Agents Chemother ; 66(1): e0165721, 2022 01 18.
Artículo en Inglés | MEDLINE | ID: mdl-34780269

RESUMEN

Ceftolozane/tazbactam (C/T) is a potent anti-pseudomonal agent that has clinical utility against infections caused by non-carbapenemase, producing-carbapenem-resistant Pseudomonas aeruginosa (non-CP-CR-PA). Accurate, precise, and reliable antimicrobial susceptibility testing (AST) is crucial to guide clinical decisions. However, studies assessing the performance of different AST methods against non-CP-CR-PA (the main clinical niche for C/T), are lacking. Here, we evaluated performance of gradient strips (Etest and MIC test strip [MTS], and disk diffusion [DD]) using CLSI breakpoints. Additionally, we assessed the performance of DD using EUCAST breakpoints. For all susceptibility tests, we used a collection of 97 non-CP-CR-PA clinical isolates recovered from 11 Chilean hospitals. Both gradient strips and DD had acceptable performance when using CLSI breakpoints, yielding a categorical agreement (CA) of >90% and 92%, respectively. In contrast, DD using EUCAST breakpoints performed suboptimally (CA 81%). MTS yielded a higher essential agreement (EA, >90%) than Etest (84%). Importantly, the performance of all methods varied significantly when the isolates were stratified by their degree of susceptibility to other anti-pseudomonal ß-lactams. All methods had 100% CA when testing isolates that were pan-susceptible to all ß-lactams (Pan-ß-S). However, the CA markedly decreased when testing isolates resistant to all ß-lactams (Pan-ß-R). Indeed, the CA was 81% for Etest (six errors), 78% for MTS (seven errors), and 78% and 56% for DD when using CLSI (seven errors) or EUCAST breakpoints (14 errors), respectively. Our results suggest that all manual AST methods have strikingly decreased performance in the context of Pan-ß-R P. aeruginosa with potentially major clinical implications.


Asunto(s)
Infecciones por Pseudomonas , Pseudomonas aeruginosa , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Carbapenémicos/farmacología , Cefalosporinas/farmacología , Humanos , Pruebas de Sensibilidad Microbiana , Infecciones por Pseudomonas/tratamiento farmacológico , Tazobactam/farmacología
12.
J Med Virol ; 93(12): 6803-6807, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34289136

RESUMEN

We evaluated the Panbio™ COVID-19 Ag Rapid Test Device as a point-of-care diagnostic tool for COVID-19 in 357 patients at a pediatric emergency department. Thirty-four patients tested positive by reverse transcription polymerase chain reaction, of which 24 were positive by the antigen assay. The sensitivity and specificity of the assay were 70.5% and 100%, respectively.


Asunto(s)
Antígenos Virales/inmunología , COVID-19/diagnóstico , COVID-19/inmunología , SARS-CoV-2/inmunología , Prueba de Ácido Nucleico para COVID-19/métodos , Prueba Serológica para COVID-19/métodos , Niño , Preescolar , Servicio de Urgencia en Hospital , Femenino , Humanos , Pruebas Inmunológicas/métodos , Lactante , Masculino , Nasofaringe/inmunología , Nasofaringe/virología , Pruebas en el Punto de Atención , Estudios Prospectivos , Sensibilidad y Especificidad
13.
Arch. cardiol. Méx ; 91(2): 190-195, abr.-jun. 2021. tab, graf
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1248784

RESUMEN

Resumen Objetivo: La insuficiencia cardiaca (IC) es un síndrome clínico caracterizado por disminución en la capacidad funcional. Los programas de rehabilitación cardiaca y prevención secundaria (PRHCyPS) han mostrado mejorar la calidad de vida y tolerancia al esfuerzo en este grupo de pacientes, pero sus efectos son dependientes del volumen. Nuestro objetivo es evaluar el grado de correlación del volumen de entrenamiento medido en equivalentes metabólicos (MET)-min/semana con el porcentaje de ganancia de consumo pico de oxígeno (VO2p) (MET-carga) posterior a un PRHCyPS en pacientes con IC. Método: Estudio cuasiexperimental que evaluó la ganancia de VO2p (MET-carga) en 31 pacientes posterior a un PRHCyPS, antes y después de una prueba de ejercicio convencional, que consistió en 30 min de entrenamiento dinámico al 70% frecuencia cardíaca de reserva (FCR) durante seis semanas, así como entrenamiento de kinesioterapia e intervención interdisciplinaria. Se calculó el volumen de entrenamiento de cada paciente en MET-min/semana (método de Kaminsky). Se midió el índice de correlación con Rho de Spearman y se consideró significancia estocástica con valor de p < 0.05. Resultados: El 70.6% fueron de sexo masculino, promedio de edad 61.5 ± 8.9 años, con fracción de expulsión del ventrículo izquierdo promedio de 38 ± 4.6%; el 96.8% de la IC fue de origen isquémico; un 55.9, un 29.4 y un 5.9% en clase funcional según la New York Heart Association I, II y III, respectivamente. Con un volumen de entrenamiento promedio de 504.34 ± 164 MET-min/semana. La mayor correlación se obtuvo en las poblaciones de alto riesgo, con una Rho: 0.486 (p = 0.008) por VO2p-carga. Conclusiones: Si bien existe una ganancia sustancial en tolerancia al esfuerzo medido por VO2p-carga, no obtuvimos suficiente grado de correlación entre el volumen de entrenamiento aplicado y la ganancia obtenida.


Abstract Objective: Heart failure is a clinical syndrome characterized by a decrease in functional capacity. Cardiac rehabilitation and secondary prevention (CR&SP) programs have been shown to improve quality of life and excercise tolerance in this group of patients, but their effects depends on training volume. Our objective is to evaluate the level of correlation of the training volume measured in metabolic equivalents (MET)-min/week with the percentage of peak oxygen consumption (VO2p) gain (estimated MET) after a CR&SP in patients with chronic heart failure. Method: Quasi-experimental study that evaluated the gain of VO2p (estimated MET) in 31 patients after a CR&SP, prior and post-exercise test, which consisted of 30 min of dynamic training at 70% heart rate reserve (HRR) for 6 weeks, with strenght training and interdisciplinary intervention. The training volume of each patient was calculated in MET-min/week (Kaminsky's method). Spearman's Rho correlation index was measured and stochastic significance was considered whith a value of p < 0.05. Results: 70.6% were male, average age 61.5 years ± 8.9, with left ventricular ejection fraction average of 38 ± 4.6%; 96.8% of the heart failure had an ischemic origin; 55.9, 29.4 and 5.9% in New York Heart Association funstional class I, II and III, respectively. With an average training volume of 504.34 ± 164 MET-min/week. The best correlation was obtained in high-risk population with Rhol: 0.486 (p = 0.008) meassured by estimated VO2p. Conclusions: Although there is a substantial gain in excersise tolerance measured by estimated VO2p, we did not obtain a sufficient level of correlation between the volume of training applied and the gain obtained.

14.
medRxiv ; 2021 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-33880478

RESUMEN

Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) is used worldwide to test and trace the spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). "Extraction-less" or "direct" real time-reverse transcription polymerase chain reaction (RT-PCR) is an open-access qualitative method for SARS-CoV-2 detection from nasopharyngeal or oral pharyngeal samples with the potential to generate actionable data more quickly, at a lower cost, and with fewer experimental resources than full RT-qPCR. This study engaged 10 global testing sites, including laboratories currently experiencing testing limitations due to reagent or equipment shortages, in an international interlaboratory ring trial. Participating laboratories were provided a common protocol, common reagents, aliquots of identical pooled clinical samples, and purified nucleic acids and used their existing in-house equipment. We observed 100% concordance across laboratories in the correct identification of all positive and negative samples, with highly similar cycle threshold values. The test also performed well when applied to locally collected patient nasopharyngeal samples, provided the viral transport media did not contain charcoal or guanidine, both of which appeared to potently inhibit the RT-PCR reaction. Our results suggest that open-access, direct RT-PCR assays are a feasible option for more efficient COVID-19 coronavirus disease testing as demanded by the continuing pandemic.

16.
J Equine Sci ; 32(4): 153-155, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35023994

RESUMEN

Cortisol is a hormone secreted by the adrenal glands that is stimulated by physiological and pathological factors and has been studied widely in equids, but not in mules. The objectives of this study were to obtain a reference value for serum cortisol in mules destined for agricultural activities and to identify age- and gender-related differences in the value. The concentration was obtained in blood samples using a commercial sandwich ELISA specific for cortisol. The concentration was 96.3 ± 40.6 ng/ml and similar between age groups and genders.

17.
Sensors (Basel) ; 20(21)2020 Oct 29.
Artículo en Inglés | MEDLINE | ID: mdl-33138049

RESUMEN

Servo systems are feedback control systems characterized by position, speed, and/or acceleration outputs. Nowadays, industrial advances make the electronic stages in these systems obsolete compared to the mechanical elements, which generates a recurring problem in technological, commercial and industrial applications. This article presents a methodology for the development of an open-architecture controller that is based on reconfigurable hardware under the open source concept for servo applications. The most outstanding contribution of this paper is the implementation of a Genetic Algorithm for online self tuning with a focus on both high-quality servo control and reduction of vibrations during the positioning of a linear motion system. The proposed techniques have been validated on a real platform and form a novel, effective approach as compared to the conventional tuning methods that employ empirical or analytical solutions and cannot improve their parameter set. The controller was elaborated from the Graphical User Interface to the logical implementation while using free tools. This approach also allows for modification and updates to be made easily, thereby reducing the susceptibility to obsolescence. A comparison of the logical implementation with the manufacturer software was also conducted in order to test the performance of free tools in FPGAs. The Graphical User Interface developed in Python presents features, such as speed profiling, controller auto-tuning, measurement of main parameters, and monitoring of servo system vibrations.

18.
Arch Cardiol Mex ; 91(2): 190-195, 2020 08 05.
Artículo en Español | MEDLINE | ID: mdl-33008149

RESUMEN

Objetivo: La insuficiencia cardiaca (IC) es un síndrome clínico caracterizado por disminución en la capacidad funcional. Los programas de rehabilitación cardiaca y prevención secundaria (PRHCyPS) han mostrado mejorar la calidad de vida y tolerancia al esfuerzo en este grupo de pacientes, pero sus efectos son dependientes del volumen. Nuestro objetivo es evaluar el grado de correlación del volumen de entrenamiento medido en equivalentes metabólicos (MET)-min/semana con el porcentaje de ganancia de consumo pico de oxígeno (VO2p) (MET-carga) posterior a un PRHCyPS en pacientes con IC. Método: Estudio cuasiexperimental que evaluó la ganancia de VO2p (MET-carga) en 31 pacientes posterior a un PRHCyPS, antes y después de una prueba de ejercicio convencional, que consistió en 30 min de entrenamiento dinámico al 70% frecuencia cardíaca de reserva (FCR) durante seis semanas, así como entrenamiento de kinesioterapia e intervención interdisciplinaria. Se calculó el volumen de entrenamiento de cada paciente en MET-min/semana (método de Kaminsky). Se midió el índice de correlación con Rho de Spearman y se consideró significancia estocástica con valor de p < 0.05. Resultados: El 70.6% fueron de sexo masculino, promedio de edad 61.5 ± 8.9 años, con fracción de expulsión del ventrículo izquierdo promedio de 38 ± 4.6%; el 96.8% de la IC fue de origen isquémico; un 55.9, un 29.4 y un 5.9% en clase funcional según la New York Heart Association I, II y III, respectivamente. Con un volumen de entrenamiento promedio de 504.34 ± 164 MET-min/semana. La mayor correlación se obtuvo en las poblaciones de alto riesgo, con una Rho: 0.486 (p = 0.008) por VO2p-carga. Conclusiones: Si bien existe una ganancia sustancial en tolerancia al esfuerzo medido por VO2p-carga, no obtuvimos suficiente grado de correlación entre el volumen de entrenamiento aplicado y la ganancia obtenida.

19.
Sensors (Basel) ; 20(18)2020 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-32957595

RESUMEN

Motion control is widely used in industrial applications since machinery, robots, conveyor bands use smooth movements in order to reach a desired position decreasing the steady error and energy consumption. In this paper, a new Proportional-Integral-Derivative (PID) -type fuzzy logic controller (FLC) tuning strategy that is based on direct fuzzy relations is proposed in order to compute the PID constants. The motion control algorithm is composed by PID-type FLC and S-curve velocity profile, which is developed in C/C++ programming language; therefore, a license is not required to reproduce the code among embedded systems. The self-tuning controller is carried out online, it depends on error and change in error to adapt according to the system variations. The experimental results were obtained in a linear platform integrated by a direct current (DC) motor connected to an encoder to measure the position. The shaft of the motor is connected to an endless screw; a cart is placed on the screw to control its position. The rise time, overshoot, and settling time values measured in the experimentation are 0.124 s, 8.985% and 0.248 s, respectively. These results presented in part 6 demonstrate the performance of the controller, since the rise time and settling time are improved according to the state of the art. Besides, these parameters are compared with different control architectures reported in the literature. This comparison is made after applying a step input signal to the DC motor.

20.
Horm Cancer ; 10(2-3): 97-106, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30903583

RESUMEN

The use of BRAFV600E and RET/PTC1 as biomarkers to guide the extent of surgery in patients with papillary thyroid cancer (PTC) remains controversial. We assessed the combined use of demographic data (sex and age) with mRNA expression levels and/or mutational status (BRAFV600E and RET/PTC1) to identify potential subsets of patients with aggressive histopathological features (lymph node metastases and extrathyroidal extension). In a cohort of 126 consecutive patients, BRAFV600E and RET/PTC1 mutations were found in 52 and 18%, respectively. By conditional bivariate analysis (CBVA), a 'high activity' profile of BRAF (BRAFV600E positive or high expression) and 'low activity' profile of RET (RET/PTC1 negative or low expression) was associated with extrathyroidal extension (ETE) (OR 4.48). Alternatively, a 'high activity' profile of RET (RET/PTC1 positive or high expression) and 'low activity' profile of BRAF (BRAFV600E negative or low expression) were associated with lymph node metastasis (LNM) (OR 12.80). Furthermore, in patients younger than 55 years, a low expression of BRAF was associated with LNM (OR 17.65) and the presence of BRAFV600E mutation was associated with ETE (OR 2.76). Our results suggest that the analysis of demographic and molecular variables by CBVA could contribute to identify subsets of patients with aggressive histopathologic features, providing a potential guide to personalised surgical management of PTC.


Asunto(s)
Proteínas Proto-Oncogénicas B-raf/metabolismo , Proteínas Proto-Oncogénicas c-ret/metabolismo , Cáncer Papilar Tiroideo/metabolismo , Neoplasias de la Tiroides/metabolismo , Adulto , Biomarcadores de Tumor/metabolismo , Análisis Mutacional de ADN , Femenino , Humanos , Ganglios Linfáticos/cirugía , Metástasis Linfática , Masculino , Persona de Mediana Edad , Mutación , Pronóstico , Estudios Prospectivos , Cáncer Papilar Tiroideo/patología , Neoplasias de la Tiroides/patología , Resultado del Tratamiento
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