Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 54
Filtrar
1.
Nat Commun ; 15(1): 2429, 2024 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-38499529

RESUMEN

Polarons and spin-orbit (SO) coupling are distinct quantum effects that play a critical role in charge transport and spin-orbitronics. Polarons originate from strong electron-phonon interaction and are ubiquitous in polarizable materials featuring electron localization, in particular 3d transition metal oxides (TMOs). On the other hand, the relativistic coupling between the spin and orbital angular momentum is notable in lattices with heavy atoms and develops in 5d TMOs, where electrons are spatially delocalized. Here we combine ab initio calculations and magnetic measurements to show that these two seemingly mutually exclusive interactions are entangled in the electron-doped SO-coupled Mott insulator Ba2Na1-xCaxOsO6 (0 < x < 1), unveiling the formation of spin-orbital bipolarons. Polaron charge trapping, favoured by the Jahn-Teller lattice activity, converts the Os 5d1 spin-orbital Jeff = 3/2 levels, characteristic of the parent compound Ba2NaOsO6 (BNOO), into a bipolaron 5d2 Jeff = 2 manifold, leading to the coexistence of different J-effective states in a single-phase material. The gradual increase of bipolarons with increasing doping creates robust in-gap states that prevents the transition to a metal phase even at ultrahigh doping, thus preserving the Mott gap across the entire doping range from d1 BNOO to d2 Ba2CaOsO6 (BCOO).

2.
Laryngoscope Investig Otolaryngol ; 8(6): 1442-1448, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38130267

RESUMEN

Objectives: Determine factors associated with delayed endoscopic sinus surgery (ESS) in patients with chronic rhinosinusitis (CRS). Methods: This is a retrospective cohort study conducted at a tertiary care academic center. Patients were included in the study if they were at least 18 years old and underwent surgery for CRS. Electronic medical records were retrospectively reviewed to collect demographic and clinical data. Patients with CRS secondary to another pathology such as malignancy were excluded. Multiple linear regression was performed to determine factors associated with the number of days between a patient's preoperative consultation and the date of surgery. Results: A total of 103 patients with a mean age of 46.6 ± 16.8 years were included in the analysis; 51.5% of patients were females, 46.6% identified as White, and 29.1% identified as Hispanic. The majority of patients (67.0%) had preferred provider organization health insurance; 43.7% of patients had nasal polyps, 70.9% had a deviated nasal septum, and the mean preoperative Sinonasal Outcomes Test-22 (SNOT-22) score was 41.0 ± 23.8. The mean time to surgery after the final preoperative visit was 71.7 days ± 65.6 days. Hispanic ethnicity was associated with increased time to surgery (p < .05) when controlling for other variables. No other variables were associated with time to surgery on multivariate analysis. Conclusion: Hispanic ethnicity may be an independent predictor of increased time to sinus surgery independent of disease severity and other demographic variables. Level of Evidence: 2b.

3.
Plants (Basel) ; 12(18)2023 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-37765386

RESUMEN

Hexavalent chromium (Cr(VI)) contamination poses serious health and environmental risks. Chromium biosorption has been employed as an effective means of eradicating Cr(VI) contamination. However, research on chromium desorption from chromium-loaded biosorbents is scarce despite its importance in facilitating industrial-scale chromium biosorption. In this study, single- and two-stage chromium desorption from chromium-loaded Cupressus lusitanica bark (CLB) was conducted. Thirty eluent solutions were evaluated first; the highest single-stage chromium desorption efficiencies were achieved when eluent solutions of 0.5 M NaOH, 0.5 M H2SO4, and 0.5 M H2C2O4 were used. Subsequently, two-stage kinetic studies of chromium desorption were performed. The results revealed that using 0.5 M NaOH solution in the first stage and 0.5 M H2C2O4 in the second stage enabled the recovery of almost all the chromium initially bound to CLB (desorption efficiency = 95.9-96.1%) within long (168 h) and short (3 h) desorption periods at each stage. This study clearly demonstrated that the oxidation state of the recovered chromium depends on the chemical nature and concentration of the eluent solution. The results suggest the possible regeneration of chromium-loaded CLB for its subsequent use in other biosorption/desorption cycles.

4.
PLoS One ; 18(8): e0289717, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37585384

RESUMEN

This paper aims to concurrently select and control off-the-shelf BLDC motors of industrial robots by using a synergistic model-based approach. The BLDC motors are considered with trapezoidal back-emf, where the three-phase (a,b,c) dynamics of motors are modeled in a mechatronic powertrain model of the robot for the selection and control problem, defining it as a multi-objective dynamic optimization problem with static and dynamic constraints. Since the mechanical and electrical actuators' parameters modify the robot's performance, the selection process considers the actuators' parameters, their control input, operational limits, and the mechanical output to the transmission of the robot joints. Then, three objective functions are to be minimized, the motor's energy consumption, the tracking error, and the total weight of installed motors on the robot mechanism. The control parameterization approach via a cascade controller with PI controllers for actuators' voltage and a PID controller for actuators' torque is used to solve the multi-objective dynamic optimization problem. Based on simulations of the closed-loop system, a Pareto front is obtained to examine trade-offs among the objective functions before implementing any actuators in the existing robotic system. The proposed method is tested on an experimental platform to verify its effectiveness. The performance of an industrial robot with the actuators originally installed is compared with the results obtained by the synergic approach. The results of this comparison show that 10.85% of electrical power can be saved, and the trajectory tracking error improved up to 57.41% using the proposed methodology.


Asunto(s)
Robótica , Electricidad , Torque
5.
Ann Otol Rhinol Laryngol ; 132(11): 1321-1329, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36647259

RESUMEN

OBJECTIVE: There is a paucity of data investigating the effect of implementation of telehealth on vulnerable populations, particularly the incarcerated. Our objective is to evaluate patient and physician satisfaction with telehealth (telephone visits) used in an outpatient otolaryngology clinic serving the incarcerated population. METHODS: Incarcerated patients who were served by otolaryngologists via telephone visits from a large tertiary care center from June 2021 to January 2022 were included (n = 20) in this pilot study. Patient and physician satisfaction with the encounters were evaluated using the Telehealth Satisfaction Questionnaire and a modified physician satisfaction questionnaire, respectively. RESULTS: Consultations for various otolaryngological complaints were completed via telephone for incarcerated patients including hearing loss, tinnitus, facial fracture, dysphonia, and tonsillitis. Mean patient and physician satisfaction scores were high at 4.25 ± 0.12 and 4.65 ± 0.13 respectively (score range 1-5). Patient satisfactions subdomain scores were 3.92 ± 0.13 for quality of care provided, 3.99 ± 0.13 for similarity to face-to-face encounter, and 4.2 ± 0.17 for perception of the interaction. Imaging or audiogram was available prior to appointment in 60% of cases, with labs, imaging, or audiogram ordered after in 40% of cases and initial pharmaceutical treatment provided to 10% of patients. 45% of patients required follow up in-person, while 40% were discharged pro re nata, and 15% were followed up with another phone visit. There was no statistically significant association between demographic or clinical characteristics and patient or physician satisfaction scores. CONCLUSIONS: Consultations for various otolaryngological complaints were completed via telephone with high patient and physician satisfaction within an incarcerated population in this pilot study. Telephone visit is likely a feasible alternative format that can advance otolaryngological care. Studies with larger sample sizes are required to ensure quality of care and advance social justice for this chronically underserved population.


Asunto(s)
Otolaringología , Prisioneros , Telemedicina , Humanos , Satisfacción del Paciente , Proyectos Piloto , Otolaringología/métodos , Telemedicina/métodos
6.
Bioprocess Biosyst Eng ; 46(2): 183-193, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36437376

RESUMEN

We investigated the capacity of water hyacinth leaves (LEC) to biosorb 75 mg/L acid red 27 (AR27) in a continuous system comprising 30 successive biosorption/desorption cycles in a packed-bed column at pH 2.0 and 56.5 L/m2·h volumetric flux. Using 0.025 M NaHCO3 eluent at 113 L/m2·h volumetric flux, all the dye was desorbed (100% desorption efficiency) from the loaded LEC biomass within 5-6 h. The same biosorbent was used for 147.5 consecutive days. The AR27 biosorption capacity, breakthrough time, and exhaustion time decreased from 69.4 to 34.5 mg/g, 74.81 to 14.1 h, and 101.1 to 34.1 h, respectively, and the critical bed height increased from 1.04 to 2.35 cm, as the number of biosorption/desorption cycles increased from 1 to 30. LEC life factor based on biosorption capacity predicted that the packed bed would be exhausted after 51.95 cycles. LEC is a promising biosorbent for bioremediation of AR27-laden wastewaters.


Asunto(s)
Eichhornia , Contaminantes Químicos del Agua , Colorante de Amaranto , Aguas Residuales , Adsorción , Concentración de Iones de Hidrógeno , Cinética , Biomasa
7.
Micromachines (Basel) ; 13(10)2022 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-36296034

RESUMEN

Around the world many people loss a body member for many reasons, where advances of technology may be useful to help these people to improve the quality of their lives. Then, designing a technologically advanced prosthesis with natural movements is worthy for scientific, commercial, and social reasons. Thus, research of manufacturing, designing, and signal processing may lead up to a low-cost affordable prosthesis. This manuscript presents a low-cost design proposal for an electromyographic electronic system, which is characterized by a neural network based process. Moreover, a hand-type prosthesis is presented and controlled by using the processed electromyographic signals for a required particular use. For this purpose, the user performs several movements by using the healthy-hand to get some electromyographic signals. After that, the obtained signals are processed in a neural network based controller. Once an usable behavior is obtained, an exact replica of controlled motions are adapted for the other hand by using the designed prosthesis. The characterization process of bioelectrical signals was performed by training twenty characteristics obtained from the original raw signal in contrast with other papers in which seven characteristics have been tested on average. The proposed model reached a 95.2% computer test accuracy and 93% accuracy in a real environment experiment. The platform was tested via online and offline, where the best response was obtained in the online execution time.

8.
Otolaryngol Clin North Am ; 55(3): 649-658, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35490046

RESUMEN

Temporomandibular disorders (TMDs) are a prominent reason for visits to medical providers. The presentation of headaches within this population remains a challenging diagnosis, given the prevalence and overlap of symptomatology of both conditions. The literature demonstrates an undeniable association between headaches and TMD. Regardless of causality and etiology, the literature supports that prompt diagnosis and treatment results in improvement or resolution of symptoms, including headaches. Treatment of TMD headaches should begin with conservative measures, including medical management with NSAIDs, heat therapy, and muscle-stretching exercises.


Asunto(s)
Trastornos de la Articulación Temporomandibular , Síndrome de la Disfunción de Articulación Temporomandibular , Cefalea , Humanos , Prevalencia , Trastornos de la Articulación Temporomandibular/epidemiología , Trastornos de la Articulación Temporomandibular/etiología , Trastornos de la Articulación Temporomandibular/terapia
9.
PLoS One ; 17(3): e0264734, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35231077

RESUMEN

The kinetics of growth and α-amylase production of a novel Candida wangnamkhiaoensis yeast strain were studied in single-stage steady-state continuous cultures. This was performed in a split-cylinder internal-loop airlift bioreactor, using a variety of carbon sources as fermentation substrates. Results showed that the steady-state yields of cell mass from carbohydrates were practically constant for the range of dilution rates assayed, equaling 0.535 ± 0.030, 0.456 ± 0.033, and 0.491 ± 0.035 g biomass/g carbohydrate, when glucose, maltose, and starch, respectively were used as carbon sources. No α-amylase activity was detected when glucose was used as the carbon source in the influent medium, indicating that α-amylase synthesis of C. wangnamkhiaoensis is catabolically repressed by glucose. Contrastingly, maltose and starch induce synthesis of α-amylase in C. wangnamkhiaoensis, with starch being the best α-amylase inducer. The highest α-amylase volumetric and specific activities (58400 ± 800 U/L and 16900 ± 200 U/g biomass, respectively), and productivities (14000 ± 200 U/L·h and 4050 ± 60 U/g biomass·h, respectively) were achieved at a dilution rate of 0.24 h-1 using starch as the carbon source. In conclusion, single-stage steady-state continuous culture in an airlift bioreactor represents a powerful tool, both for studying the regulatory mechanisms of α-amylase synthesis by C. wangnamkhiaoensis and for α-amylase production. Furthermore, results showed that C. wangnamkhiaoensis represents a potential yeast species for the biotechnological production of α-amylase, which can be used for the saccharification of starch. This offers an attractive renewable resource for the production of biofuels (particularly bioethanol), representing an alternative to fossil fuels with reduced cost of substrates.


Asunto(s)
Maltosa , alfa-Amilasas , Amilasas , Reactores Biológicos , Carbohidratos , Carbono , Glucosa , Saccharomycetales , Almidón
10.
Laryngoscope ; 131(3): 553-558, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-32668033

RESUMEN

OBJECTIVES: Persistent or recurrent disease following excision of a thyroglossal duct cyst/sinus (TGDC) is often found in the suprahyoid region. Cadaver dissections were performed to identify and name important surgical landmarks in the suprahyoid area; a histopathologic analysis of surgical specimens was completed to determine the incidence and extent of microscopic disease; and clinical outcomes were compared to determine the efficacy of a specific anatomic dissection. STUDY DESIGN: Retrospective case series. METHODS: Standardized dissections of four adult cadavers were performed. Consecutive surgical specimens were examined for evidence of microscopic TDGC disease in the suprahyoid region, measuring the greatest width and length of disease. A retrospective review of all consecutive TGDC procedures was completed. RESULTS: The important surgical landmarks in the suprahyoid area were identified in all cadavers. Microscopic disease in the suprahyoid area was found in 79% (37 of 47) of surgical specimens. The mean greatest length and width of microscopic disease was 12.4 mm and 1.4 mm, respectively. Following identification of these landmarks, the incidence of recurrent or persistent disease decreased (P = .02) from 5% (8 of 159) to 0% (0 of 112). CONCLUSION: The majority of pediatric patients with a TGDC will have microscopic disease in the suprahyoid area. The surgical landmark of the fascial plane between the geniohyoid and genioglossus muscles demarcates the anterior and lateral borders of resection in the suprahyoid area. This approach can be used as a reliable and easily reproducible technique in TGDC surgery to increase confidence of achieving complete removal of disease in the suprahyoid area, avoiding persistent or recurrent disease and a revision procedure. LEVEL OF EVIDENCE: 4 Laryngoscope, 131:553-558, 2021.


Asunto(s)
Puntos Anatómicos de Referencia/cirugía , Disección del Cuello/métodos , Cuello/anatomía & histología , Cuello/cirugía , Quiste Tirogloso/cirugía , Adulto , Cadáver , Niño , Femenino , Humanos , Hueso Hioides/anatomía & histología , Hueso Hioides/cirugía , Masculino , Estudios Retrospectivos , Glándula Tiroides/anatomía & histología , Glándula Tiroides/cirugía , Lengua/anatomía & histología , Lengua/cirugía
11.
Rejuvenation Res ; 24(1): 6-13, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32323640

RESUMEN

Physical exercise is a potential intervention to revert or attenuate frailty syndrome, which may be accomplished by traditional center-based and home-based programs. This study aimed to compare the effectiveness of a home-based and center-based exercise program on frailty status, physical and muscle function of frail older women. Thirty-one frail older women were allocated in two different groups: home-based group (n = 17, 71.5 ± 6.5 years) or center-based group (n = 14, 68.4 ± 6.4 years). The exercise program lasted 12 weeks (3 days/week), 60 minutes/session, including strengthening, balance, and gait exercises. Frailty status, knee, and hip strength, and physical function were assessed before and after the intervention. After the exercise program, frailty was reversed in 76% of the participants independently of the exercise group. Muscle strength and physical function improved in both groups, where the home-based program presented a high adherence rate, and the center-based program was more suitable to reverse the frailty status. In conclusion, a home-based exercise program is as effective as center based to improve strength, physical function, and to reverse frailty status.


Asunto(s)
Ejercicio Físico , Anciano Frágil , Fragilidad , Anciano , Terapia por Ejercicio , Femenino , Humanos , Persona de Mediana Edad , Fuerza Muscular
12.
PLoS One ; 15(1): e0227953, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31961884

RESUMEN

Continuous fixed-bed column studies were carried out, utilizing acorn shell from Quercus crassipes Humb. & Bonpl. (QCS), in order to remove total chromium and Cr(VI) from aqueous solution. Effects of various fixed-bed column parameters such as influent solution pH, influent flow rate, QCS bed height, and influent Cr(VI) concentration were investigated. Results from the fixed-bed column experiments demonstrate that total chromium biosorption and Cr(VI) removal by QCS depend strongly on the pH of influent solution. The highest capacities for Cr(VI) removal and total chromium biosorption are about 181.56 and 110.35 mg g-1 and are achieved at influent solution pH of 1.0 and 2.0, respectively. Besides this, total chromium biosorption capacities increased from 104.25 to 116.14 mg g-1, 109.07 to 117.44 mg g-1, and 85.02 to 129.87 mg g-1, as bed height, inlet flow rate, and influent Cr(VI) concentration increased from 1.7 to 6.5 cm, 0.25 to 1 mL min-1, and 50 to 400 mg L-1, respectively. The dose-response model defines the entire breakthrough curve for total chromium biosorption onto QCS, under all experimental conditions. X-ray photoelectron spectroscopy (XPS) and biosorption kinetic studies revealed that QCS is able to remove toxic Cr(VI) from acidic liquid solution by means of a complex mechanism that involves the binding of Cr(VI) oxyanions to positively charged groups present at the QCS surface, after which the Cr(VI) species are reduced to Cr(III) by adjacent electron donor groups, and the generated Cr(III) ions then become partially bound to the QCS biomass and partially released into the liquid phase. Results show that QCS can be employed as an easily accessible, abundant, eco-friendly, and inexpensive biosorbent for the removal of total chromium and Cr(VI) from Cr(VI) solutions, in continuous operation.


Asunto(s)
Cromatografía Liquida/métodos , Cromo/química , Quercus/química , Contaminantes Químicos del Agua/química , Adsorción , Cinética , Agua/química
13.
J Power Sources ; 4362019 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-31824126

RESUMEN

Charging a commercial lithium-ion battery intercalates lithium into the graphite-based anode, creating various lithium carbide structures. Despite their economic importance, these structures and the dynamics of their charging-discharging transitions are not well-understood. We have videoed single microcrystals of high-quality, natural graphite undergoing multiple lithiation-delithiation cycles. Because the equilibrium lithium-carbide compounds corresponding to full, half, and one-third charge are gold, red, and blue respectively, video observations give direct insight into both the macromolecular structures and the kinematics of charging and discharging. We find that the transport during the first lithiation is slow and orderly, and follows the core-shell or shrinking annuli model with phase boundaries moving at constant velocities (i.e. non-diffusively). Subsequent lithiations are markedly different, showing transport that is both faster and disorderly, which indicates that the initially pristine graphite is irreversibly and considerably altered during the first cycle. In all cases deintercalation is not the time-reverse of intercalation. These findings both illustrate how lithium enters nearly defect-free host material, and highlight the differences between the idealized case and an actual, cycling graphite anode.

14.
Artículo en Inglés | MEDLINE | ID: mdl-31131002

RESUMEN

BACKGROUND: Pore-forming proteins (PFP) are a class of toxins abundant in the venom of sea anemones. Owing to their ability to recognize and permeabilize cell membranes, pore-forming proteins have medical potential in cancer therapy or as biosensors. In the present study, we showed the partial purification and sequencing of a pore-forming protein from Anthopleura dowii Verrill (1869). 17. METHODS: Cytolytic activity of A. dowii Verrill (1869) venom was determined via hemolysis assay in the erythrocytes of four mammals (sheep, goat, human and rabbit). The cytotoxic activity was analyzed in the human adherent lung carcinoma epithelial cells (A549) by the cytosolic lactate dehydrogenase (LDH) assay, and trypan blue staining. The venom was fractionated via ammonium sulfate precipitation gradient, dialysis, and ion exchange chromatography. The presence of a pore-forming protein in purified fractions was evaluated through hemolytic and cytotoxic assays, and the activity fraction was analyzed using the percent of osmotic protections after polyethylene glycol (PEG) treatment and mass spectrometry. 18. RESULTS: The amount of protein at which the venom produced 50% hemolysis (HU50) was determined in hemolysis assays using erythrocytes from sheep (HU50 = 10.7 ± 0.2 µg), goat (HU50 = 13.2 ± 0.3 µg), rabbit (HU50 = 34.7 ± 0.5 µg), and human (HU50 = 25.6 ± 0.6 µg). The venom presented a cytotoxic effect in A549 cells and the protein amount present in the venom responsible for producing 50% death (IC50) was determined using a trypan blue cytotoxicity assay (1.84 ± 0.40 µg/mL). The loss of membrane integrity in the A549 cells caused by the venom was detected by the release of LDH in proportion to the amount of protein. The venom was fractionated; and the fraction with hemolytic and cytotoxic activities was analyzed by mass spectrometry. A pore-forming protein was identified. The cytotoxicity in the A549 cells produced by the fraction containing the pore-forming protein was osmotically protected by PEG-3350 Da molecular mass, which corroborated that the loss of integrity in the plasma membrane was produced via pore formation. 19. Conclusion: A. dowii Verrill (1869) venom contains a pore-forming protein suitable for designing new drugs for cancer therapy.

15.
Environ Sci Pollut Res Int ; 26(4): 3157-3173, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28963647

RESUMEN

Solution pH appears to be the most important regulator of the biosorptive removal of chromium ions from aqueous solutions. This work presents a kinetic study of the effects of solution pH on Cr(VI) and total chromium removal from aqueous solution by Hass avocado shell (HAS) in batch and continuous packed bed column systems. Different Cr(VI) and total chromium removal performances of HAS were obtained in pH-shift batch, pH-controlled batch, and continuous systems. These results emphasize the great importance of determining the most appropriate pH for Cr(VI) and total chromium removal, considering the operational mode of the proposed large-scale treatment system. Total chromium biosorption batch kinetics was well described by the Elovich model, whereas in the continuous system, the fitness of the kinetic models to the experimental data was pH dependent. X-ray photoelectron spectroscopy and kinetic studies clearly indicated that the reaction mechanism of Cr(VI) with HAS was the reductive biotransformation of Cr(VI) to Cr(III), which was partially released to the aqueous solution and partially biosorbed onto HAS.


Asunto(s)
Cromo/análisis , Persea/química , Contaminantes Químicos del Agua/análisis , Purificación del Agua/métodos , Adsorción , Frutas/química , Concentración de Iones de Hidrógeno , Cinética , Modelos Teóricos , Soluciones , Aguas Residuales/química
16.
Laryngoscope ; 129(5): 1215-1217, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30194760

RESUMEN

OBJECTIVE: Despite the success of the Sistrunk procedure, persistence of a thyroglossal duct cyst (TGDC), sinus, or remnant following excision remains a clinical problem. This is most likely due to the presence of microscopic disease that was not excised at the time of surgery. The purpose of this study is to determine the incidence of microscopic disease superior to the hyoid bone in children who have had either a primary or revision procedure for a TGDC. METHODS: A prospective review of pathologic specimens was conducted of all consecutive patients undergoing TGDC excision by pediatric otolaryngologists at the Children's Hospital Los Angeles beginning March 2014 through July 2017 in both primary and revision procedures. RESULTS: Microscopic disease was present superior to the hyoid bone in 25 of the 34 (74%) specimens and in 100% (6) of the specimens from a revision procedure. CONCLUSION: The majority of persons who have a TGDC will have microscopic disease superior to the hyoid bone. In order to minimize the incidence of persistence following a primary procedure, tissue superior to the hyoid bone should be removed routinely even if no gross disease is noted at the time of surgery. When performing a revision procedure, special attention should be given to the suprahyoid area as a likely site of persistent disease. LEVEL OF EVIDENCE: 2b Laryngoscope, 129:1215-1217, 2019.


Asunto(s)
Quiste Tirogloso/epidemiología , Quiste Tirogloso/patología , Adolescente , Niño , Preescolar , Femenino , Humanos , Hueso Hioides , Incidencia , Lactante , Masculino , Estudios Prospectivos , Insuficiencia del Tratamiento
17.
J. venom. anim. toxins incl. trop. dis ; 25: e147418, 2019. graf, ilus
Artículo en Inglés | LILACS | ID: biblio-984697

RESUMEN

Background: Pore-forming proteins (PFP) are a class of toxins abundant in the venom of sea anemones. Owing to their ability to recognize and permeabilize cell membranes, pore-forming proteins have medical potential in cancer therapy or as biosensors. In the present study, we showed the partial purification and sequencing of a pore-forming protein from Anthopleura dowii Verrill (1869). 17. Methods: Cytolytic activity of A. dowii Verrill (1869) venom was determined via hemolysis assay in the erythrocytes of four mammals (sheep, goat, human and rabbit). The cytotoxic activity was analyzed in the human adherent lung carcinoma epithelial cells (A549) by the cytosolic lactate dehydrogenase (LDH) assay, and trypan blue staining. The venom was fractionated via ammonium sulfate precipitation gradient, dialysis, and ion exchange chromatography. The presence of a pore-forming protein in purified fractions was evaluated through hemolytic and cytotoxic assays, and the activity fraction was analyzed using the percent of osmotic protections after polyethylene glycol (PEG) treatment and mass spectrometry. 18. Results: The amount of protein at which the venom produced 50% hemolysis (HU50) was determined in hemolysis assays using erythrocytes from sheep (HU50 = 10.7 ± 0.2 µg), goat (HU50 = 13.2 ± 0.3 µg), rabbit (HU50 = 34.7 ± 0.5 µg), and human (HU50 = 25.6 ± 0.6 µg). The venom presented a cytotoxic effect in A549 cells and the protein amount present in the venom responsible for producing 50% death (IC50) was determined using a trypan blue cytotoxicity assay (1.84 ± 0.40 µg/mL). The loss of membrane integrity in the A549 cells caused by the venom was detected by the release of LDH in proportion to the amount of protein. The venom was fractionated; and the fraction with hemolytic and cytotoxic activities was analyzed by mass spectrometry. A pore-forming protein was identified. The cytotoxicity in the A549 cells produced by the fraction containing the pore-forming protein was osmotically protected by PEG-3350 Da molecular mass, which corroborated that the loss of integrity in the plasma membrane was produced via pore formation. 19. Conclusion: A. dowii Verrill (1869) venom contains a pore-forming protein suitable for designing new drugs for cancer therapy.(AU)


Asunto(s)
Humanos , Animales , Anémonas de Mar , Venenos de Cnidarios/aislamiento & purificación , Neoplasias Pulmonares/terapia , Venenos/toxicidad , Espectrometría de Masas/métodos , Células A549
18.
Ginecol. obstet. Méx ; 87(5): 277-287, ene. 2019. tab, graf
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1286618

RESUMEN

Resumen OBJETIVO: Determinar la correlación entre el cálculo del índice de riesgo de malignidad de Jacobs II y el reporte anatomopatológico de tumores de ovario. MATERIALES Y MÉTODOS: Estudio observacional, retrospectivo y prospectivo, analítico y transversal efectuado en pacientes con diagnóstico de tumoración ovárica con marcador tumoral de Ca 125 atendidas en el Hospital Christus Muguerza Conchita, Nuevo León, de 2016 a 2018. Se realizó el cálculo del índice de riesgo de malignidad de Jacobs II: IRM = U x M x Ca 125. Las pacientes se dividieron dos grupos según los reportes de histopatología (benignos y malignos). Las variables de tendencia central se compararon con t de Student ajustada a normalidad de dos colas (p < 0.05). Para describir las diferencias entre los grupos los muestreos categóricos se compararon con la prueba de Fisher de 2 colas o distribución de c2 (p < 0.05). Se estudió la muestra para observar factores de riesgo-beneficio (AUROC) y determinar el coeficiente de momios, riesgo relativo, sensibilidad, especificidad y creación del modelo de regresión logística de los indicadores de interés. RESULTADOS: Se seleccionaron 323 pacientes con diagnóstico de tumoración ovárica y se encontró que las pacientes con un índice de malignidad de Jacobs II mayor de 155.22 (AUROC 0.95) tuvieron mayor probabilidad de tener una lesión maligna por patología, con sensibilidad de 88% y especificidad de 91%. CONCLUSIÓN: Existe una correlación entre el índice de riesgo de malignidad de Jacobs II con el reporte anatomopatológico de tumores de ovario.


Abstract OBJECTIVE: To determine the correlation between the risk of malignancy index Jacobs II and anatomopathological result in ovarian tumors. MATERIALS AND METHODS: Observational, retrospective, prospective, analytical and transversal study of patients with a diagnosis of ovarian tumor with tumor marker of Ca 125 and the result of pathology admitted to the Christus Muguerza Conchita Hospital in Nuevo León during a 2-year period (2016-2018). Risk of malignancy index Jacobs II was calculated: IRM = U x M x Ca 125. Two groups were divided according to the results of histopathology (benign and malignant). For variables of central tendency, were compared with Student's t-test adjusted to two-tailed normality (P <0.05). For categorical sampling, compared with the 2-tailed Fisher's test to describe the differences between the groups or distribution c2 (P <0.05). The sample was studied to observe risk / benefit factors (AUROC) as well as determination of the odds ratio, relative risk, sensitivity, specificity and creation of the logistic regression model of the indicators of interest. RESULTS: It was found that patients with a Jacobs II malignancy index higher than 155.22 (AUROC 0.95) were more likely to have a malignant lesion due to pathology with 88% sensitivity and 91% specificity. CONCLUSION: There is a correlation between the risk index for malignancy of Jacobs II and the anatomopathological result in ovarian tumors.

19.
Percept Mot Skills ; 125(2): 329-350, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29368530

RESUMEN

This study examined the extent to which different high-intensity interval training (HIIT) and sprint interval training (SIT) protocols could influence psychophysiological responses in moderately active young men. Fourteen participants completed, in a randomized order, three cycling protocols (SIT: 4 × 30-second all-out sprints; Tabata: 7 × 20 seconds at 170% ⋮O2max; and HIIT: 10 × 60 seconds at 90% HRmax) and three running HIIT protocols (4 × 4 minutes at 90%-95% HRmax, 5 × at v⋮O2max, and 4 × 1,000 meters at a rating of perceived exertion (RPE) of 8, from the OMNI-Walk/Run scale). Oxygen uptake (⋮O2), heart rate, and RPE were recorded during each interval. Affective responses were assessed before and after each trial. The Tabata protocol elicited the highest ⋮O2 and RPE responses, and the least pleasant session-affect among the cycling trials. The v⋮O2max elicited the highest ⋮O2 and RPE responses and the lowest mean session-affect among the running trials. Findings highlight the limited application of SIT and some HIIT protocols to individuals with low fitness levels.


Asunto(s)
Afecto/fisiología , Frecuencia Cardíaca/fisiología , Entrenamiento de Intervalos de Alta Intensidad , Consumo de Oxígeno/fisiología , Esfuerzo Físico/fisiología , Aptitud Física/fisiología , Adulto , Humanos , Masculino , Adulto Joven
20.
Childs Nerv Syst ; 34(4): 787-789, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29294141

RESUMEN

INTRODUCTION: This case examines a unique, longitudinal presentation of an abandoned, migrating VP shunt which presents as multiple complications, including a weeping abscess in the patients back. We believe that the latter complication was potentially caused by the wound from the patient's previous history of spinal fusion surgery. CASE PRESENTATION: The patient presents with an associated type 2 Chiari malformation, hydrocephalus, and a previous history of posterior spinal fusion (T4-L5 anterior fusion and T2-L5 posterior fusion) at age 11. The patient had undergone shunt revisions in early adolescence as well. At 22, the patient is admitted into emergency care due to recurrent infections caused by a migrating VP shunt. Due to complications in corrective surgery at the time, the shunt was forced to be abandoned. This resulted in the most recent presentation of a weeping abscess at the patient's spinal fusion surgery wound; the culprit was the abandoned, migrating VP shunt.. MANAGEMENT/OUTCOME: An initial course of broad-spectrum antibiotics was started. However, the abscess continued to recur. Eventually, the catheter was surgically removed, a tailored antibiotic regiment was started, and a 6-month patient follow-up was performed. The patient is no longer symptomatic and off of antibiotics. DISCUSSION: In abandoned VP shunts, migration into a non-sterile cavity dictates prompt removal, especially after symptoms of infection present. Additionally, careful monitoring for signs of peritonitis or other symptoms for a dedicated period of time is necessary. To the authors' best knowledge, this is the first case of an occult shunt migration through the patient's back that presented with a weeping abscess.


Asunto(s)
Malformación de Arnold-Chiari/cirugía , Migración de Cuerpo Extraño/etiología , Prótesis e Implantes/efectos adversos , Espina Bífida Oculta/cirugía , Fusión Vertebral/efectos adversos , Derivación Ventriculoperitoneal/efectos adversos , Adulto , Malformación de Arnold-Chiari/complicaciones , Migración de Cuerpo Extraño/diagnóstico por imagen , Humanos , Masculino , Espina Bífida Oculta/complicaciones , Fusión Vertebral/métodos , Tomógrafos Computarizados por Rayos X
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...