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1.
Oncologist ; 29(3): e337-e344, 2024 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-38071748

RESUMEN

BACKGROUND: Liquid biopsy (LB) is a non-invasive tool to evaluate the heterogeneity of tumors. Since RAS mutations (RAS-mut) play a major role in resistance to antiepidermal growth factor receptor inhibitors (EGFR) monoclonal antibodies (Mabs), serial monitoring of RAS-mut with LB may be useful to guide treatment. The main aim of this study was to evaluate the prognostic value of the loss of RAS-mut (NeoRAS-wt) in LB, during the treatment of metastatic colorectal cancer (mCRC). METHODS: A retrospective study was conducted on patients with mCRC between January 2018 and December 2021. RAS-mut were examined in tissue biopsy, at mCRC diagnosis, and with LB, during treatment. RESULTS: Thirty-nine patients with RAS-mut mCRC were studied. LB was performed after a median of 3 lines (0-7) of systemic treatment including anti-vascular endothelial growth factor (anti-VEGF) Mabs. NeoRAS-wt was detected in 13 patients (33.3%); 9 (69.2%) of them received further treatment with anti-EGFR Mabs with a disease control rate of 44.4%. Median overall survival (OS), from the date of LB testing, was 20 months in the NeoRAS-wt group and 9 months in the persistent RAS-mut group (log-rank 2.985; P = .08), with a 12-month OS of 84.6% and 57.7%, respectively. NeoRAS-wt was identified as a predictor of survival (HR = 0.29; P = .007), with an 11-month improvement in median OS and a 71% decrease in risk of death, in heavily pretreated patients. CONCLUSIONS: In conclusion, monitoring clonal evolution in mCRC by LB may provide an additional treatment line for patients with NeoRAS-wt in advanced disease.


Asunto(s)
Antineoplásicos , Neoplasias del Colon , Neoplasias Colorrectales , Neoplasias del Recto , Humanos , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/patología , Estudios Retrospectivos , Antineoplásicos/uso terapéutico , Anticuerpos Monoclonales/uso terapéutico , Biopsia Líquida , Mutación
2.
Dis Esophagus ; 37(1)2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-37528744

RESUMEN

Low sphincter pressure and inability of the crural diaphragm to elevate it at the esophagogastric junction are important pathophysiological mechanisms of gastroesophageal reflux disease (GERD). The object of this study was to depict how Nissen fundoplication changed the resting and inspiratory pressures of the anti-reflux barrier. We selected 14 patients (eight males; mean age 42.7 years; mean body mass index 27.8) for surgery. They answered symptoms questionnaires and underwent high-resolution manometry (HRM) before and 6 months after Nissen fundoplication. We used a standard manometric protocol (resting and liquid swallows) and assessment of esophagogastric junction (EGJ) pressure metrics during standardized forced inspiratory maneuvers against increasing loads (Threshold Maneuvers). We used the Wilcoxon test for comparison of pre and postoperative data. After fundoplication, heartburn and regurgitation scores diminished remarkably (from 4.5 and 2, respectively, to zero; P = 0.002 and P = 0.0005, respective medians). Also, the median expiratory EGJ pressure had a significant increase from 8.1 to 18.1 mmHg (P = 0.002), while mean respiratory pressure and EGJ contractility integral (EGJ-CI) increased without statistical significance (P = 0.064 and P = 0.06, respectively). Axial EGJ displacement was lower after fundoplication. The EGJ relaxation pressure (P = 0.001), the mean distal esophageal intrabolus pressure (P = 0.01) and the distal latency (P = 0.017) increased after fundoplication. There was a reduction in the contraction front velocity (P = 0.043). During evaluation with standardized inspiratory maneuvers, the inspiratory EGJ pressures (under loads of 12, 24, 36 and 48 cmH2O) were lower after surgery for all loads (median for load 12 cmH2O: 145.6 vs. 102.7 mmHg; P = 0.004). Fundoplication and hiatal closure increased the expiratory EGJ pressure and promoted a great GERD symptom relief. The surgery seemed to overcompensate a reduced EGJ mobility and inspiratory pressure.


Asunto(s)
Fundoplicación , Reflujo Gastroesofágico , Masculino , Humanos , Adulto , Unión Esofagogástrica/cirugía , Reflujo Gastroesofágico/cirugía , Manometría/métodos
3.
Vascular ; : 17085381241236587, 2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38413049

RESUMEN

OBJECTIVE: Long-pulsed 1064 nm Nd:YAG laser can damage vessels with higher diameters and penetrate to a deeper level than other laser therapies. We aim to analyze outcomes of the treatment of leg veins with long-pulsed 1064 nm Nd:YAG laser regarding intervention protocol, technical success, clinical success, and side effects. METHODS: A research of the published literature was conducted, using PubMed and Embase databases, in April 2022. The key words used were telangiectasia, reticular veins, neodymium YAG laser, clearance, satisfaction, and treatment. PRISMA guidelines were followed. RESULTS: We included twenty-six articles, twenty-three prospective and three retrospective studies, with a total of 1991 patients. The articles were organized in different sections according to the control group. The four outcomes were analyzed in each section. These studies showed that the long-pulsed 1064 nm Nd:YAG laser is a safe and very good option for the treatment of leg veins measuring up to 3 mm in diameter. Studies comparing long-pulsed 1064 nm Nd:YAG laser therapy and sclerotherapy showed similar clearance rates with no significant differences. However, sclerotherapy seemed to be less painful and to have faster clinical improvements. In two articles, Nd:YAG laser had better outcomes in the treatment of smaller vessels with less than 1 mm in diameter, than sclerotherapy alone. Treatment with polidocanol microfoam and Nd:YAG laser had better clearance rates than Nd:YAG laser alone in three studies. In the comparison of 1064 nm Nd:YAG laser therapy with other lasers and light sources, the studies had contradictory results. CONCLUSION: Long-pulsed 1064 nm Nd:YAG laser is a valid therapeutic option for leg telangiectasia and reticular veins with great aesthetic outcomes and minor side effects. Nd:YAG laser therapy could be combined with sclerotherapy or other laser therapies or IPL in order to achieve better results. Serious side effects are rare, but the procedure is almost always accompanied by moderate tolerable pain.

4.
Sensors (Basel) ; 24(10)2024 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-38793904

RESUMEN

Underwater long-endurance platforms are crucial for continuous oceanic observation, allowing for sustained data collection from a multitude of sensors deployed across diverse underwater environments. They extend mission durations, reduce maintenance needs, and significantly improve the efficiency and cost-effectiveness of oceanographic research endeavors. This paper investigates the closed-loop depth control of actuation systems employed in underwater vehicles, focusing on the energy consumption of two different mechanisms: variable buoyancy and propeller actuated devices. Using a prototype previously developed by the authors, this paper presents a detailed model of the vehicle using both actuation solutions. The proposed model, although being a linear-based one, accounts for several nonlinearities that are present such as saturations, sensor quantization, and the actuator brake model. Also, it allows a simple estimation of the energy consumption of both actuation solutions. Based on the developed models, this study then explores the intricate interplay between energy consumption and control accuracy. To this end, several PID-based controllers are developed and tested in simulation. These controllers are used to evaluate the dynamic response and power requirements of variable buoyancy systems and propeller actuated devices under various operational conditions. Our findings contribute to the optimization of closed-loop depth control strategies, offering insights into the trade-offs between energy efficiency and system effectiveness in diverse underwater applications.

5.
Int J Mol Sci ; 25(11)2024 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-38891904

RESUMEN

Tooth loss during the lifetime of an individual is common. A strategy to treat partial or complete edentulous patients is the placement of dental implants. However, dental implants are subject to bacterial colonization and biofilm formation, which cause an infection named peri-implantitis. The existing long-term treatments for peri-implantitis are generally inefficient. Thus, an electrical circuit was produced with zirconia (Zr) samples using a hot-pressing technique to impregnate silver (Ag) through channels and holes to create a path by LASER texturing. The obtained specimens were characterized according to vitro cytotoxicity, to ensure ZrAg non-toxicity. Furthermore, samples were inoculated with Staphylococcus aureus using 6.5 mA of alternating current (AC). The current was delivered using a potentiostat and the influence on the bacterial concentration was assessed. Using AC, the specimens displayed no bacterial adhesion (Log 7 reduction). The in vitro results presented in this study suggest that this kind of treatment can be an alternative and promising strategy to treat and overcome bacterial adhesion around dental implants that can evolve to biofilm.


Asunto(s)
Adhesión Bacteriana , Biopelículas , Implantes Dentales , Staphylococcus aureus , Circonio , Implantes Dentales/microbiología , Circonio/química , Biopelículas/crecimiento & desarrollo , Biopelículas/efectos de los fármacos , Humanos , Estimulación Eléctrica/métodos , Propiedades de Superficie , Periimplantitis/microbiología , Periimplantitis/terapia , Plata/química , Plata/farmacología
6.
J Environ Manage ; 358: 120854, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38640759

RESUMEN

The use of rare earth elements (REEs) has been increasing and one of the most used is neodymium (Nd). Being an emergent contaminant, its negative impacts are poorly understood. Aquatic organisms are also threatened by climate change-related factors, as is the case of warming, which can change the effects of REEs. Thus, the impacts of Nd, warming, and the combination of both stressors were studied in adult mussels and sperm of the species Mytilus galloprovincialis, after an exposure period of 28 days (adults) and 30 min (sperm). The effects were evaluated through the analysis of biochemical and histopathological alterations in adults and biochemical and physiological responses given by sperm. The results showed that mussels only activated their biotransformation capacity when exposed to the stressors acting alone, which was insufficient to avoid lipid peroxidation. Furthermore, warming (alone and combined with Nd) also produces damage to proteins. The digestive gland was the most sensitive organ to Nd, presenting several histopathological alterations. In the case of sperm, all stressors induced lipid peroxidation, a higher oxygen demand, and a decrease in velocity, even if the sperm viability was maintained. It seems that warming influenced the effects of Nd to some extent. The present findings contribute significantly to the field of REEs environmental toxicology by offering valuable insights into the impacts of Nd on various biological levels of mussels. Additionally, within the context of climate change, this study sheds light on how temperature influences the effects of Nd. The obtained results indicate that both stressors can potentially compromise the overall health of mussel populations, thereby affecting other species reliant on them for food and habitat. Moreover, this study highlights impaired sperm health, which could adversely affect their reproductive capacity and ultimately lead to population decline.


Asunto(s)
Mytilus , Neodimio , Espermatozoides , Animales , Mytilus/fisiología , Masculino , Peroxidación de Lípido , Cambio Climático , Contaminantes Químicos del Agua/toxicidad
7.
Exp Physiol ; 108(6): 852-864, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37018484

RESUMEN

NEW FINDINGS: What is the central question of this study? The aim was to identify the factors predicting the body core temperature of athletes at the end of a 10 km self-paced run in a hot environment. What is the main finding and its importance? Hyperthermia in athletes subjected to self-paced running depends on several factors, highlighting the integrated control of core temperature during exercise under environmental heat stress. Five of the seven variables that significantly predicted core temperature are not invasive and, therefore, practical for use outside the laboratory environment: heart rate, sweat rate, wet-bulb globe temperature, running speed and maximal oxygen consumption. ABSTRACT: Measurement of body core temperature (Tcore ) is paramount to determining the thermoregulatory strain of athletes. However, standard measurement procedures of Tcore are not practical for extended use outside the laboratory environment. Therefore, determining the factors that predict Tcore during a self-paced run is crucial for creating more effective strategies to minimize the heat-induced impairment of endurance performance and reduce the occurrence of exertional heatstroke. The aim of this study was to identify the factors predicting Tcore values attained at the end of a 10 km time trial (end-Tcore ) under environmental heat stress. Initially, we extracted data obtained from 75 recordings of recreationally trained men and women. Next, we ran hierarchical multiple linear regression analyses to understand the predictive power of the following variables: wet-bulb globe temperature, average running speed, initial Tcore , body mass, differences between Tcore and skin temperature (Tskin ), sweat rate, maximal oxygen uptake, heart rate and change in body mass. Our data indicated that Tcore increased continuously during exercise, attaining 39.6 ± 0.5°C (mean ± SD) after 53.9 ± 7.5 min of treadmill running. This end-Tcore value was primarily predicted by heart rate, sweat rate, differences between Tcore and Tskin , wet-bulb globe temperature, initial Tcore , running speed and maximal oxygen uptake, in this order of importance (ß power values corresponded to 0.462, -0.395, 0.393, 0.327, 0.277, 0.244 and 0.228, respectively). In conclusion, several factors predict Tcore in athletes subjected to self-paced running under environmental heat stress. Moreover, considering the conditions investigated, heart rate and sweat rate, two practical (non-invasive) variables, have the highest predictive power.


Asunto(s)
Trastornos de Estrés por Calor , Carrera , Masculino , Humanos , Femenino , Temperatura Corporal/fisiología , Temperatura , Calor , Regulación de la Temperatura Corporal/fisiología , Carrera/fisiología , Respuesta al Choque Térmico/fisiología , Oxígeno
8.
Mol Pharm ; 20(2): 1112-1128, 2023 02 06.
Artículo en Inglés | MEDLINE | ID: mdl-36651656

RESUMEN

Mechanoactivation has attracted considerable attention in the pharmaceutical sciences due to its ability to generate amorphous materials and solid-state synthetic products without the use of solvent. Although some studies have reported drug degradation during milling, no studies have systematically investigated the use of mechanoactivation in predicting drug degradation in the solid state. Thus, this work explores the autoxidation of drugs in the solid state by comilling amorphous mifepristone (MFP):polyvinylpyrrolidone vinyl acetate (PVPVA) and amorphous olanzapine (OLA):PVPVA. MFP was amorphized by ball milling and OLA by quench cooling techniques. Subsequently, comilling the amorphous drugs in the presence of a 10-fold weight ratio of PVPVA (the excipient containing reactive free radicals) was performed at several milling frequencies to identify the kinetics of mechano-autoxidation over milling durations. Overall, milling led to the degradation of up to 5% drug in the solid state. The autoxidation mechanism was confirmed by performing a stress study in the solution at 50 °C for 5 h, by using a 10 mM azo-bis(isobutyronitrile) (AIBN) as a stressing agent. By deconvoluting the effect of milling frequency and the energy on the extent and kinetics of milling-induced autoxidation of amorphous drugs, it was possible to fit an extended Arrhenius model that allowed extrapolation of mechanoactivated degradation rates (Km) to zero milling frequencies. Further, the autoxidation rates of drugs stored at high temperatures were observed to follow an Arrhenius behavior. A good degree of agreement was observed between the model predictions obtained by mechanoactivation (Km) to the reaction rates observed under accelerated temperatures. Additionally, the impact of adding an antioxidant (e.g., butylated hydroxytoluene) to the mixture during comilling was also examined. This study can be helpful in evaluating the stability of amorphous solids stored in accelerated (non-hermetic) conditions, in screening solid-state autoxidation propensity of drugs, and for the rational selection of antioxidants.


Asunto(s)
Povidona , Cristalización , Transición de Fase , Temperatura , Estabilidad de Medicamentos
9.
Harm Reduct J ; 20(1): 84, 2023 07 03.
Artículo en Inglés | MEDLINE | ID: mdl-37400843

RESUMEN

The economic, social, cultural and political milieus that influence injection drug-related HIV risk behaviors along the US-Mexico border in the previous decade have been studied comparing cities on an East-West axis. In an effort to inform interventions targeting factors beyond the individual level, we used a cross-sectional study design comparing people who inject drugs during 2016-2018, living on a North-South axis, in two cities-Ciudad Juárez, Chihuahua, Mexico and El Paso, Texas, USA-situated at the midpoint of the 2000 US-Mexico borderland stretch. We conceptualize injection drug use and its antecedents and consequences as influenced by factors operating at various levels of influence. Results of analysis comparing samples recruited from each border city indicated significant differences in demographic, socioeconomic, micro- and macro-level factors that affect risk. Similarities emerged in individual-level risk behaviors and some dynamics of risk at the drug use site most frequented to use drugs. In addition, analyses testing associations across samples indicated that different contextual factors such as characteristics of the drug use sites influenced syringe sharing. In this article, we reflect on the potential tailored interventions needed to target the context of HIV transmission risk among people who use drugs and reside in binational environment.


Asunto(s)
Infecciones por VIH , Abuso de Sustancias por Vía Intravenosa , Trastornos Relacionados con Sustancias , Humanos , Infecciones por VIH/epidemiología , Estudios Transversales , Ciudades , Abuso de Sustancias por Vía Intravenosa/epidemiología , México/epidemiología
10.
J Stroke Cerebrovasc Dis ; 32(1): 106864, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36434859

RESUMEN

BACKGROUND: Although sleep apnea and peripheral artery disease are prognostic factors for stroke, their added benefit in the acute stage to further prognosticate strokes has not been evaluated. OBJECTIVES: We tested the accuracy in the acute stroke stage of a novel score called the Non-Invasive Prognostic Stroke Scale (NIPSS). PATIENTS AND METHODS: Prospective cohort with imaging-confirmed ischemic stroke. Clinical data, sleep apnea risk score (STOPBANG) and blood pressure measures were collected at baseline. Primary outcome was the 90-day modified Rankin Scale (mRS), with poor outcome defined as mRS 3-6. Area under the ROC curve (AUC) was calculated for NIPSS and compared to six other stroke prognostic scores in our cohort: SPAN-100 index, S-SMART, SOAR, ASTRAL, THRIVE, and Dutch Stroke scores. RESULTS: We enrolled 386 participants. After 90 days, there were 56% with poor outcome, more frequently older, female predominant and with higher admission National Institute of Health Stroke Scale (NIHSS). Four variables remained significantly associated with primary endpoint in the multivariable model: age (OR 1.87), NIHSS (OR 7.08), STOPBANG category (OR 1.61), and ankle-braquial index (OR 2.11). NIPSS AUC was 0.86 (0.82-0.89); 0.83 (0.79-0.87) with bootstrapping. When compared to the other scores, NIPSS, ASTRAL, S-SMART and DUTCH scores had good abilities in predicting poor outcome, with AUC of 0.86, 0.86, 0.83 and 0.82, respectively. THRIVE, SOAR and SPAN-100 scores were fairly predictive. DISCUSSION AND CONCLUSIONS: Non-invasive and easily acquired emergency room data can predict clinical outcome after stroke. NIPSS performed equal to or better than other prognostic stroke scales.


Asunto(s)
Isquemia Encefálica , Enfermedad Arterial Periférica , Síndromes de la Apnea del Sueño , Accidente Cerebrovascular , Humanos , Femenino , Pronóstico , Isquemia Encefálica/diagnóstico , Isquemia Encefálica/terapia , Estudios Prospectivos , Triaje , Accidente Cerebrovascular/diagnóstico , Accidente Cerebrovascular/terapia , Enfermedad Arterial Periférica/diagnóstico , Resultado del Tratamiento
11.
Fetal Pediatr Pathol ; 42(4): 685-689, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36881016

RESUMEN

BACKGROUND: Skene's glands are the two largest paraurethral glands and the female homologue to the prostate glands. When their ducts become obstructed, cysts may be formed. This usually occurs in adult women. Most cases reported in pediatrics are neonatal, with a single report in a prepubertal girl. CASE REPORT: We present a 25-month-old girl with a 7 mm nontender, solid, oval, pink-orange paraurethral mass, with no change over a five-month period. Histopathology revealed the cyst to be lined with transitional epithelium consistent with a Skene's gland cyst. The child did well with no sequalae. CONCLUSION: We describe a Skene's gland cyst found in a prepubertal child.


Asunto(s)
Quistes , Masculino , Adulto , Recién Nacido , Femenino , Humanos , Niño , Preescolar , Quistes/diagnóstico , Epitelio
12.
Appl Environ Microbiol ; 88(9): e0247621, 2022 05 10.
Artículo en Inglés | MEDLINE | ID: mdl-35416684

RESUMEN

Whole-genome transcriptional analyses performed on microorganisms are traditionally based on a small number of samples. To map transient expression variations, and thoroughly characterize gene expression throughout the growth curve of the widely used model organism Lactococcus lactis MG1363, gene expression data were collected with unprecedented time resolution. The resulting gene expression patterns were globally analyzed in several different ways to demonstrate the richness of the data and the ease with which novel phenomena can be discovered. When the culture moves from one growth phase to another, gene expression patterns change to such an extent that we suggest that those patterns can be used to unequivocally distinguish growth phases from each other. Also, within the classically defined growth phases, subgrowth phases were distinguishable with a distinct expression signature. Apart from the global expression pattern shifts seen throughout the growth curve, several cases of short-lived transient gene expression patterns were clearly observed. These could help explain the gene expression variations frequently observed in biological replicates. A method was devised to estimate a measure of unnormalized/absolute gene expression levels and used to determine how global transcription patterns are influenced by nutrient starvation or acidification of the medium. Notably, we inferred that L. lactis MG1363 produces proteins with on average lower pIs and lower molecular weights as the medium acidifies and nutrients get scarcer. IMPORTANCE This data set is a rich resource for microbiologists interested in common mechanisms of gene expression, regulation and in particular the physiology of L. lactis. Thus, similar to the common use of genome sequence data by the scientific community, the data set constitutes an extensive data repository for mining and an opportunity for bioinformaticians to develop novel tools for in-depth analysis.


Asunto(s)
Lactococcus lactis , Adaptación Fisiológica , Concentración de Iones de Hidrógeno , Lactococcus lactis/metabolismo , Nutrientes , Transcriptoma
13.
Mol Pharm ; 19(1): 51-66, 2022 01 03.
Artículo en Inglés | MEDLINE | ID: mdl-34919407

RESUMEN

Understanding the dissolution mechanisms of amorphous solid dispersions (ASDs) and being able to link enhanced drug exposure with process parameters are key when formulating poorly soluble compounds. Thus, in this study, ASDs composed by itraconazole (ITZ) and hydroxypropylmethylcellulose acetate succinate (HPMCAS) were formulated with different polymer grades and drug loads (DLs) and processed by spray drying with different atomization ratios and outlet temperatures. Their in vitro performance and the ability to form drug-rich colloids were then evaluated by a physiologically relevant dissolution method. In gastric media, drug release followed a diffusion-controlled mechanism and drug-rich colloids were not formed since the solubility of the amorphous API at pH 1.6 was not exceeded. After changing to intestinal media, the API followed a polymer dissolution-controlled release, where the polymer rapidly dissolved, promoting the immediate release of API and thus leading to liquid-liquid phase separation (LLPS) and consequent formation of drug-rich colloids. However, the release of API and polymer was not congruent, so API surface enrichment occurred, which limited the further dissolution of the polymer, leading to a drug-controlled release. ASDs formulated with M-grade showed the highest ability to maintain supersaturation and the lowest tendency for AAPS due to its good balance between acetyl and succinoyl groups, and thus strong interactions with both the hydrophobic drug and the aqueous dissolution medium. The ability to form colloids increased for low DL (15%) and high specific surface area due to the high amount of polymer released until the occurrence of API surface enrichment. Even though congruent release was not observed, all ASDs formed drug-rich colloids that were stable in the solution until the end of the dissolution study (4 h), maintaining the same size distribution (ca. 300 nm). Drug-rich colloids can, in vivo, act as a drug reservoir replenishing the drug while it permeates. Designing ASDs that are prone to form colloids can overcome the solubility constraints of Biopharmaceutics Classification System (BCS) II and IV drugs, posing as a reliable formulation strategy.


Asunto(s)
Coloides/química , Composición de Medicamentos , Itraconazol/administración & dosificación , Metilcelulosa/análogos & derivados , Rastreo Diferencial de Calorimetría , Combinación de Medicamentos , Composición de Medicamentos/métodos , Liberación de Fármacos , Itraconazol/análisis , Itraconazol/química , Metilcelulosa/administración & dosificación , Metilcelulosa/análisis , Metilcelulosa/química , Microscopía Electrónica de Rastreo , Tamaño de la Partícula , Difracción de Rayos X
14.
Surg Endosc ; 36(4): 2456-2465, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-33999254

RESUMEN

BACKGROUND: Laboratory skills training is an essential step before conducting minimally invasive surgery in clinical practice. Our main aim was to develop an animal model for training in clinically highly challenging laparoscopic duodenal atresia repair that could be useful in establishing a minimum number of repetitions to indicate safe performance of similar interventions on humans. MATERIALS AND METHODS: A rabbit model of laparoscopic duodenum atresia surgery involving a diamond-shaped duodeno-duodenostomy was designed. This approach was tested in two groups of surgeons: in a beginner group without any previous clinical laparoscopic experience (but having undergone previous standardized dry-lab training, n = 8) and in an advanced group comprising pediatric surgery fellows with previous clinical experience of laparoscopy (n = 7). Each participant performed eight interventions. Surgical time, expert assessment using the Global Operative Assessment of Laparoscopic Skills (GOALS) score, anastomosis quality (leakage) and results from participant feedback questionnaires were analyzed. RESULTS: Participants in both groups successfully completed all eight surgeries. The surgical time gradually improved in both groups, but it was typically shorter in the advanced group than in the beginner group. The leakage rate was significantly lower in the advanced group in the first two interventions, and it reached its optimal level after five operations in both groups. The GOALS and participant feedback scores showed gradual increases, evident even after the fifth surgery. CONCLUSIONS: Our data confirm the feasibility of this advanced pediatric laparoscopic model. Surgical time, anastomosis quality, GOALS score and self-assessment parameters adequately quantify technical improvement among the participants. Anastomosis quality reaches its optimal value after the fifth operation even in novice, but uniformly trained surgeons. A minimum number of wet-lab operations can be determined before surgery can be safely conducted in a clinical setting, where the development of further non-technical skills is also required.


Asunto(s)
Obstrucción Duodenal , Atresia Intestinal , Laparoscopía , Animales , Niño , Competencia Clínica , Obstrucción Duodenal/cirugía , Humanos , Atresia Intestinal/cirugía , Laparoscopía/educación , Conejos
15.
Inj Prev ; 28(3): 280-287, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35361666

RESUMEN

CONTEXT: Despite the growing evidence regarding surf-related injuries, investigation seems to overlook the differences between professional and recreational surfers' injuries and their specific risk factors. OBJECTIVE: This review aimed at identifying differences in injuries sustained by recreational and competitive surfers. It also presents research gaps and suggests recommendations for future injury research and prevention. METHODS: Study search was conducted on MEDLINE/PubMed, SportDiscus and Web of Science databases. To be included studies needed to report original data, clearly specify if recreational and/or competitive surfers were included, provide information regarding acute surfing injuries and/or analyse data concerning those injuries. RESULTS: 17 studies were included in the analysis. All included studies had at least Oxford Centre for Evidence-Based Medicine level of evidence 3. The percentage of recreational surfers sustaining at least one injury ranged from 31% to 35% in the 12 months prior to data collection and from 88% to 100% in lifetime while 42% to 49% and 81% to 100% of competitors were injured over the same periods. Competitive surfers appear to have a higher injury risk. Both recreational and competitive surfers appear to sustain more frequently skin, joint/ligament and muscle/tendon injuries affecting the lower limbs and caused by contact with their own equipment. CONCLUSIONS: Competitive status, less surfing experience, older age and prior surgical injuries are risk factors for sustaining injuries while surfing. The most common types, anatomical locations and mechanisms of injury seem to be similar between recreational and competitive surfers.


Asunto(s)
Traumatismos en Atletas , Deportes , Traumatismos en Atletas/epidemiología , Traumatismos en Atletas/prevención & control , Humanos , Extremidad Inferior , Factores de Riesgo
16.
BMC Med Inform Decis Mak ; 22(1): 314, 2022 11 29.
Artículo en Inglés | MEDLINE | ID: mdl-36447207

RESUMEN

BACKGROUND: The standard configuration's set of twelve electrocardiogram (ECG) leads is optimal for the medical diagnosis of diverse cardiac conditions. However, it requires ten electrodes on the patient's limbs and chest, which is uncomfortable and cumbersome. Interlead conversion methods can reconstruct missing leads and enable more comfortable acquisitions, including in wearable devices, while still allowing for adequate diagnoses. Currently, methodologies for interlead ECG conversion either require multiple reference (input) leads and/or require input signals to be temporally aligned considering the ECG landmarks. METHODS: Unlike the methods in the literature, this paper studies the possibility of converting ECG signals into all twelve standard configuration leads using signal segments from only one reference lead, without temporal alignment (blindly-segmented). The proposed methodology is based on a deep learning encoder-decoder U-Net architecture, which is compared with adaptations based on convolutional autoencoders and label refinement networks. Moreover, the method is explored for conversion with one single shared encoder or multiple individual encoders for each lead. RESULTS: Despite the more challenging settings, the proposed methodology was able to attain state-of-the-art level performance in multiple target leads, and both lead I and lead II seem especially suitable to convert certain sets of leads. In cross-database tests, the methodology offered promising results despite acquisition setup differences. Furthermore, results show that the presence of medical conditions does not have a considerable effect on the method's performance. CONCLUSIONS: This study shows the feasibility of converting ECG signals using single-lead blindly-segmented inputs. Although the results are promising, further efforts should be devoted towards the improvement of the methodologies, especially the robustness to diverse acquisition setups, in order to be applicable to cardiac health monitoring in wearable devices and less obtrusive clinical scenarios.


Asunto(s)
Cardiopatías , Dispositivos Electrónicos Vestibles , Humanos , Electrocardiografía , Electrodos , Bases de Datos Factuales
17.
Int J Mol Sci ; 23(18)2022 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-36142179

RESUMEN

The preparation of amorphous and co-amorphous systems (CAMs) effectively addresses the solubility and bioavailability issues of poorly water-soluble chemical entities. However, stress conditions imposed during common pharmaceutical processing (e.g., tableting) may cause the recrystallization of the systems, warranting close stability monitoring throughout production. This work aimed at assessing the water and heat stability of amorphous olanzapine (OLZ) and OLZ-CAMs when subject to wet granulation and pelletization. Starting materials and products were characterized using calorimetry, diffractometry and spectroscopy, and their performance behavior was evaluated by dissolution testing. The results indicated that amorphous OLZ was reconverted back to a crystalline state after exposure to water and heat; conversely, OLZ-CAMs stabilized with saccharin (SAC), a sulfonic acid, did not show any significant loss of the amorphous content, confirming the higher stability of OLZ in the CAM. Besides resistance under the processing conditions of the dosage forms considered, OLZ-CAMs presented a higher solubility and dissolution rate than the respective crystalline counterpart. Furthermore, in situ co-amorphization of OLZ and SAC during granule production with high fractions of water unveils the possibility of reducing production steps and associated costs.


Asunto(s)
Sacarina , Agua , Cristalización , Estabilidad de Medicamentos , Olanzapina , Solubilidad , Ácidos Sulfónicos , Comprimidos , Agua/química , Difracción de Rayos X
18.
Opt Express ; 29(4): 5808-5818, 2021 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-33726113

RESUMEN

Three different types of strain and temperature sensors based on negative curvature hollow core fiber (NCHCF) are proposed. Each sensor is produced by splicing a small section of the NCHCF between two sections of single mode fiber. Different types of interferometers are obtained simply by changing the splicing conditions. The first sensor consists on a single Fabry-Perot interferometer (FPI). The remaining two configurations are attained with the same sensing structure, depending on its position in relation to the interrogation setup. Thus, a double FPI or a hybrid sensor, the latter being composed by an FPI and a Michelson interferometer, are formed. The inline sensors are of submillimeter size, thus enabling nearly punctual measurements.

19.
J Environ Manage ; 300: 113697, 2021 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-34543961

RESUMEN

Dysprosium (Dy) is a rare earth element with a high economic and strategic value, and simultaneously an emerging contaminant, whose removal from wastewaters is gaining increasing attention. In this work, the Response Surface Methodology (RSM) combined with a Box-Behnken Design (3 factors-3 levels) was used to optimize the key operational conditions that influence the uptake of Dy by two living seaweed, Ulva sp. and Gracilaria sp.. The initial concentration of Dy (10-500 µg/L), water salinity (10-30), and seaweed dosage (0.5-5.5 g/L) were the independent variables, while the removal efficiency (%) and bioaccumulation (q, µg/g) were the response variables. Results highlighted the high capacity of both species to capture Dy. After 168 h, the optimal conditions that led to a maximum of 91 % of Dy removed by Gracilaria sp. were: 500 µg of Dy per L of water, salinity 10, and 5.5 g of seaweed per L. For Ulva sp., a maximum removal percentage of 79 % was achieved in the conditions: any initial concentration of Dy, salinity 20, and seaweed dosage of 3.7 g/L. Independently of the species, the response surfaces showed that the most important variable for the removal is the seaweed dosage, while for bioaccumulation is the initial concentration of Dy. Using RSM, it was possible to obtain the optimal operating conditions for Dy removal from waters, which is a fundamental step toward the application of the proposed technology at large scale.


Asunto(s)
Algas Marinas , Ulva , Contaminantes Químicos del Agua , Disprosio , Agua , Contaminantes Químicos del Agua/análisis
20.
Molecules ; 26(8)2021 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-33923713

RESUMEN

Microencapsulation procedures have recently focused attention on designing novel microspheres via green synthesis strategies. The use of chitosan (CS) as an encapsulating material has increased interest due to its unique bioactive properties and the various crosslinking possibilities offered by their functional groups. The consolidation of the microspheres by physical crosslinking using sodium tripolyphosphate (TPP) combined with chemical crosslinking using vanillin (VA) open new opportunities in the framework of green dual crosslinking strategies. The developed strategy, a straightforward technique based on an aqueous medium avoiding complex separation/washing steps, offers advantages over the processes based on VA, mostly using water-in-oil emulsion approaches. Thus, in this work, the combination of TPP crosslinking (3, 5, and 10 wt.%) via spray-coagulation technique with two VA crosslinking methods (in situ and post-treatment using 1 wt.% VA) were employed in the preparation of microspheres. The microspheres were characterized concerning morphology, particle size, physicochemical properties, thermal stability, and swelling behavior. Results revealed that the combination of 5 wt.% TPP with in situ VA crosslinking led to microspheres with promising properties, being an attractive alternative for natural bioactives encapsulation due to the green connotations associated with the process.


Asunto(s)
Benzaldehídos/química , Quitosano/química , Polifosfatos/química , Emulsiones , Microesferas
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