RESUMEN
Heavy metals can act as selective agents in the development and proliferation of antibiotic-resistant bacteria through a process called coselection. In the year 2050, an estimated 10 million deaths will be caused by antibiotic-resistant bacteria; therefore, the presence of heavy metals in bodies of water represents an environmental and sanitary threat that requires efficient treatment processes and/or materials for their removal. In the present study, the effect of the hydroxyapatite coating on the adsorbent capacity of cadmium in alumina spheres was evaluated. The hydroxyapatite coating on the alumina sphere increased the surface area from 0.66 to 0.96 m2/g and the number of acid sites from 0.064 to 0.306 meq/g and displaced the IEP of hydroxyapatite from 5.37 to 4.2, increasing the Cd2+ adsorbing capacity from 59.87 mg/g to 89.37 mg/g and promoting adsorption by surface complexation. Alumina-hydroxyapatite spheres stand out for their improved adsorbent properties and easy handling, which positioned this material as a potential alternative in adsorption processes.
RESUMEN
The present work studied individual and binary adsorption of fluorides and As(V) in water on pleco fish bone chars (BC), as well as the effect of BC mass variation on the adsorption capacity of fluoride and As(V) in water for human consumption. The results of individual adsorption indicated that the adsorption of fluoride and As(V) on BC depends on solution pH. The adsorption capacity of fluorides at an initial concentration of 30 mg L-1 increases approximately 3 times, from 5.9 to 15.3 mg g-1, when decreasing the pH of the solution from 9 to 5, however, for the case of As(V) an antagonistic effect is observed, the adsorption capacity increases 7 times when raising the pH from 5 to 9, from 18.4 to 132.1 µg g-1 at an initial As(V) concentration of 300 µg L-1. Besides, in the binary adsorption, BC showed a higher affinity to adsorb fluoride since its adsorption capacity decreased from 16.55 to 12.50 mg g-1 as the As(V) concentration increased from 0 to 800 µg L-1 in solution. In contrast, As(V) adsorption was severely affected, decreasing from 140.2 to 32.7 µg g-1 when the fluoride concentration in the solution increased from 0 to 100 mg L-1. On the other hand, in the adsorption of groundwater contaminated with fluoride and As(V), it was determined that increasing the mass of BC from 0.5 to 20 g increases the removal percentage, reaching 99.3 and 75.7% removal for fluoride and As(V), respectively, due to the fact that increasing the mass of the adsorbent leads to a larger area and a greater number of sites that allow the adsorption of these contaminants. The thermodynamic study revealed the spontaneity of fluoride and As(V) adsorption, better affinity for fluoride but higher adsorption rate of As(V) on BC. Characterization techniques such as XRD and EDS allowed identifying hydroxyapatite as the mineral phase of BC, which is responsible for the adsorption of BC. By studying the effect of solution pH on the adsorption capacities and the characterization of BC such as XRD, EDS and TGA, it was determined that the mechanisms of fluoride adsorption are by electrostatic attractions and ion exchange, and for As(V) it is by coprecipitation and ion exchange. It was concluded that BC from pleco fish could be an alternative for treating water contaminated by fluorides and As(V).
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Water pollution is a current global concern caused by emerging pollutants like nonylphenol (NP). This endocrine disruptor cannot be efficiently removed with traditional wastewater treatment plants (WTPs). Therefore, this work aimed to evaluate the adsorption influence of molecularly imprinted polymers (MIPs) on the oxidative degradation (ozone and ultraviolet irradiations) of 4-nonylphenol (4-NP) and its by-products as a coadjuvant in WTPs. MIPs were synthesized and characterized; the effect of the degradation rate under system operating conditions was studied by Box-Behnken response surface design of experiments. The variables evaluated were 4-NP concentration, ozone exposure time, pH, and MIP amount. Results show that the MIPs synthesized by co-precipitation and bulk polymerizations obtained the highest retention rates (> 90%). The maximum adsorption capacities for 4-NP were 201.1 mg L-1 and 500 mg L-1, respectively. The degradation percentages under O3 and UV conditions reached 98-100% at 120 s of exposure at different pHs. The degradation products of 4-NP were compounds with carboxylic and ketonic acids, and the MIP adsorption was between 50 and 60%. Our results present the first application of MIPs in oxidation processes for 4-NP, representing starting points for the use of highly selective materials to identify and remove emerging pollutants and their degradation by-products in environmental matrices.
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Contaminantes Ambientales , Impresión Molecular , Ozono , Polímeros Impresos Molecularmente , Impresión Molecular/métodos , Polímeros/química , Estrés Oxidativo , AdsorciónRESUMEN
In this study, a series of molecularly imprinted polymers (MIPs) have been synthesized using separately diclofenac, naproxen, and ibuprofen as templates with three different polymerization approaches. Two functional monomers, methacrylic acid (MAA) and 2-vinylpyridine (2-VP), were tested and ethylene glycol dimethacrylate (EGDMA) was used as crosslinker; also, template-free polymers (NIPs) were synthesized. It was found that the MIP with the highest retention percentage for diclofenac was the one prepared by the emulsion approach and with MAA (98.3%); for naproxen, the one prepared by the bulk polymerization with MAA (99%); and for ibuprofen, the one synthesized by bulk with 2-VP (97.7%). These three MIPs were characterized by scanning electron microscopy, thermogravimetric test, Fourier transform infrared, specific area measurements, and surface charge. It was found that the emulsion method allowed particle size control, while the bulk method gave heterogeneous particles. The three evaluated MIPs exhibited thermal stability up to 300 °C, and it was observed that 2-VP confers greater stability to the material. From the BET analysis, it was demonstrated that the MIPs and NIPs evaluated are mesoporous materials with a pore size between 10 and 20 nm. In addition, the monomer influenced the surface charge of the material, since the MAA conferred an acidic point of zero charge (PZC), while the 2-VP conferred a PZC of basic character. Through adsorption isotherms, it was determined that there is a higher adsorption capacity of the MIPs at acidic pH following a pseudo-second-order kinetic model. Finally, the MIPs were used to determine the non-steroidal anti-inflammatory drugs (NSAIDs) understudy in San Luis Potosí, México, wastewater, finding concentrations of 0.642, 0.985, and 0.403 mg L-1 for DCF, NPX, and IBP, respectively.
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Impresión Molecular , Adsorción , Antiinflamatorios no Esteroideos/análisis , Diclofenaco/análisis , Emulsiones , Ibuprofeno , Impresión Molecular/métodos , Polímeros Impresos Molecularmente , Naproxeno/análisis , Aguas Residuales/análisisRESUMEN
BACKGROUND: Patients admitted to the hospital after successful resuscitation from sudden cardiac death (SCD) are treated with therapeutic hypothermia (TH) to facilitate brain preservation. The prognostic significance of J (Osborn) waves (JOW) in the 12 leads electrocardiogram in this setting has not been elucidated as yet. OBJECTIVES: To ascertain retrospectively the prognostic significance of JOW recorded during TH in SCD survivors. METHODS: The study comprised 55 consecutive patients who underwent TH. All patients achieved a core temperature of 33°C at the time of electrocardiogram analysis. We compared 33 patients with JOW to 22 patients without JOW. The endpoints were in-hospital, long-term all-cause mortality, and irreversible anoxic brain injury (IABI). RESULTS: Patients with JOW compared to patients without JOW were younger (55.1 ± 11.6 vs. 64.5 ± 11.7 years, respectively, P < 0.006), with a lower incidence of hypertension (52% vs. 86%, P < 0.007), diabetes mellitus (15% vs. 50%, P < 0.005), and congestive heart failure (15% vs. 45%, P < 0.013). In-hospital and long-term mortality were significantly higher in patients without JOW (86% vs. 21%, 91% vs. 24%, respectively, P < 0.000001). Among patients without JOW who survived hospitalization, 66.7% presented with IABI versus 7.7% of the patients with JOW (P < 0.0001). In multivariate analysis, the absence of JOW was a significant predictor for poor prognosis. CONCLUSIONS: The absence of J (Osborn) waves on electrocardiograms obtained during TH is associated with poor prognosis among SCD survivors.
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Lesiones Encefálicas/etiología , Electrocardiografía , Hipotermia Inducida/métodos , Paro Cardíaco Extrahospitalario/terapia , Adulto , Factores de Edad , Anciano , Lesiones Encefálicas/epidemiología , Reanimación Cardiopulmonar/métodos , Femenino , Estudios de Seguimiento , Mortalidad Hospitalaria , Hospitalización , Humanos , Masculino , Persona de Mediana Edad , Paro Cardíaco Extrahospitalario/complicaciones , Paro Cardíaco Extrahospitalario/mortalidad , Pronóstico , Estudios Retrospectivos , SobrevivientesRESUMEN
Chili seeds (CS) represent one of the most abundant residues in Mexico due to the high production and consumption. In this work, CS were used as raw material for the production of low-cost adsorbents for the removal of methylene blue from water. The adsorbents were synthesized from a hydrothermal treatment (based on a surface response experiment design) and characterized texturally by assessing changes in their properties. The mass yield (%R), carbon content (%C), and the second order adsorption rate constant (k2) were derived in relation to a list of input variables (e.g., the reaction temperature, residence time, and water/biomass ratio). Accordingly, those output variables were affected most sensitively by temperature and/or residence time, while changes of the water/biomass ratio were insignificant. Besides, an increase in the reaction temperature favored the degradation of the lignocellulosic material with increases in the carbon fixation. The adsorption capacity of methylene blue (MB) by the hydrochars depended drastically on the oxygen/carbon ratio. As such, the maximum adsorption capacity value of 145 mg g-1 was attained at the initial MB concentration of ~3000 µM (optimal oxygen/carbon value of 0.43). On the other hand, the maximum partition coefficient (KD) was estimated as 2.96 µM-1 mg g-1 with the initial/equilibrium concentrations of 20.5/6.93 µM. The performance evaluation between different studies, when made in terms of KD, suggests that the tested hydrochar should be one of the best adsorbents to treat methylene blue, especially at near-real environmental conditions (e.g., below micromolar levels).
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Capsicum , Contaminantes Químicos del Agua , Purificación del Agua , Adsorción , Concentración de Iones de Hidrógeno , Cinética , Azul de Metileno/análisis , México , Semillas/química , Agua , Contaminantes Químicos del Agua/análisisRESUMEN
INTRODUCTION: Life expectancy of less than 1 year is usually a contraindication for implantable cardioverter defibrillator (ICD) implantation. The aim was to identify patients at risk of death during the first year after implantation. METHODS AND RESULTS: Data were derived from a prospective Israeli ICD Registry. Two groups of patients were compared, those who died and those who were alive 1 year after ICD implantation. Factors associated with 1-year mortality were identified on a derivation cohort. A risk score was established and validated. A total of 2617 patients have completed 1 year of follow-up after ICD or cardiac resynchronization therapy defibrillator (CRT-D) implantation. Age greater than 75 years (hazard ratio [HR], 2.7; 95% confidence interval [95% CI], 1.6 to 4.4), atrial fibrillation (AF; HR, 1.9; 95% CI, 1.12 to 3.17), chronic lung disease (HR, 2.0; 95% CI, 1.1 to 3.76), anemia (HR, 2.3; 95% CI, 1.3 to 3.93) and chronic renal failure (CRF; HR, 3.4; 95% CI, 1.74 to 6.6) were independent risk factors for 1-year mortality. We propose a simple AAACC ("triple A double C") score for prediction of 1-year mortality after ICD implantation: Age greater than 75 years (3 points(pts)), anemia (2 pts), AF (1 pt), CRF (3 pts) and chronic lung disease (1 pt). Mortality risk increased with rising number of points (from 1% with 0 pts to 12.5% with >4 pts). The risk score was evaluated with receiver operating characteristic curve and the area under the curve of the validation curve is 0.71 (95% CI, 0.66 to 0.76). CONCLUSIONS: Age greater than 75, AF, chronic lung disease, anemia, and CRF were independent risk factors for 1-year mortality. AAACC risk score identifies patients at high risk of death during 1 year after ICD implantation.
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Fibrilación Atrial/mortalidad , Fibrilación Atrial/terapia , Desfibriladores Implantables/tendencias , Cardioversión Eléctrica/mortalidad , Cardioversión Eléctrica/tendencias , Sistema de Registros , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Análisis de Datos , Muerte Súbita Cardíaca/epidemiología , Muerte Súbita Cardíaca/prevención & control , Desfibriladores Implantables/efectos adversos , Cardioversión Eléctrica/efectos adversos , Femenino , Estudios de Seguimiento , Humanos , Israel/epidemiología , Masculino , Persona de Mediana Edad , Mortalidad/tendencias , Valor Predictivo de las Pruebas , Estudios Prospectivos , Factores de RiesgoRESUMEN
BACKGROUND: Survival of patients who were discharged from the hospital following out-of-hospital cardiac arrest (OHCA) has not been well defined. OBJECTIVES: To verify predictor variables for prognosis of patients following OHCA who survived hospitalization. METHODS: We retrospectively reviewed clinical, demographic, and outcome data of consecutive patients who were hospitalized from January 1, 2009, through December 31, 2014, into the intensive coronary care unit (ICCU) after aborted OHCA and discharged alive. The patients were followed until December 31, 2015. RESULTS: Of the 180 patients who were admitted into ICCU after OHCA, 64 were discharged alive (59.3%): 55 were male (85.9%), 14 died 16.5 ± 18 months after their discharge. During 1 year follow-up, nine patients (14.1%) died after a median period of 5.5 months and 55 patients (85.9 %) survived. Diabetes mellitus and chronic renal failure (CRF) were more frequent in patients who died within 1 year after their hospital discharge than those who survived. Ventricular fibrillation, such as initial arrhythmia, and opening of occluded infarct related artery were more frequent in survivors. CONCLUSIONS: Most of the patients who were discharged after OHCA were alive at the 1 year follow-up. The risk of death of cardiac arrest survivors is greatest during the first year after discharge. CRF remains a poor long-term prognostic factor beyond the patients' discharge. Ventricular fibrillation, as initial arrhythmia, and opening of occluded infarct related artery have a positive impact on long-term survival.
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Reanimación Cardiopulmonar , Paro Cardíaco Extrahospitalario , Alta del Paciente/estadística & datos numéricos , Anciano , Reanimación Cardiopulmonar/métodos , Reanimación Cardiopulmonar/estadística & datos numéricos , Unidades de Cuidados Coronarios/estadística & datos numéricos , Femenino , Hospitalización/estadística & datos numéricos , Humanos , Israel/epidemiología , Masculino , Persona de Mediana Edad , Mortalidad , Infarto del Miocardio/epidemiología , Paro Cardíaco Extrahospitalario/mortalidad , Paro Cardíaco Extrahospitalario/terapia , Pronóstico , Medición de Riesgo/métodos , Factores de Riesgo , Tasa de Supervivencia , Tiempo , Fibrilación Ventricular/epidemiologíaRESUMEN
AIMS: For patients with high-risk, locally bulky prostate cancer, an intra-prostatic boost to tumour volumes (dose-painting) offers a risk-adapted dose escalation. We evaluated the feasibility of hypofractionated dose-painting radiotherapy and the associated toxicity. The possibility to streamline a radiobiologically optimised planning protocol was also investigated. MATERIALS AND METHODS: Twenty-eight patients were treated using a dose-painting approach; boost volumes were identified with functional magnetic resonance imaging scans. The prostate dose outside the boost volume was 60 Gy in 20 fractions, and the maximum integrated boost dose was set to 68 Gy, provided that the dose constraints to the organs at risk could be fulfilled. Rotational intensity-modulated radiotherapy was used with daily image guidance and fiducial markers. RESULTS: The boost dose was escalated to 68 Gy for 25 patients (median dose 69 Gy, range 68-70 Gy); for three patients the boost dose was 67 Gy, due to the proximity of the urethra and/or the rectum. The mean normal tissue complication probability for rectal bleeding was 4.7% (range 3.4-5.8%) and was 3.5% for faecal incontinence (range 2.3-5.0%). At a median follow-up of 38 months (range 32-45) there was no grade 3 toxicity. Two patients developed grade 2 genitourinary toxicity (7.1%) and none developed grade 2 gastrointestinal toxicity. The mean prostate-specific antigen (PSA) for 23 patients who had stopped the adjuvant hormone therapy with a normal testosterone was 0.27 ng/ml (0.02-0.72) at follow-up; two patients have suppressed PSA and testosterone after stopping 3 year adjuvant hormone and three patients have relapsed (one pelvic node, two PSA only) at 36, 12 and 42 months, respectively. CONCLUSIONS: A hypofractionated radiotherapy schedule, 60 Gy in 20 fractions with intra-prostatic boost dose of 68 Gy, can be achieved without exceeding dose constraints for organs at risk. Hypofractionated dose-painting escalated radiotherapy has an acceptable safety profile. The same planning protocol was used in a phase II single-arm trial (BIOPROP20: ClinicalTrials.gov identifier NCT02125175) and will further be used in a large phase III randomised trial (PIVOTALboost): patients will be randomised standard radiotherapy (60 Gy in 20 fractions) with or without lymph node radiotherapy versus dose-painting radiotherapy with or without lymph node radiotherapy; the trial will be opened for recruitment in summer 2017.
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Fraccionamiento de la Dosis de Radiación , Neoplasias de la Próstata/radioterapia , Radioterapia de Intensidad Modulada/métodos , Anciano , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Proyectos Piloto , Estudios Prospectivos , Radioterapia de Intensidad Modulada/efectos adversosRESUMEN
AIMS: To describe the treatment of 11 patients with radiobiologically guided dose-painting radiotherapy and report on toxicity. MATERIALS AND METHODS: Boost volumes were identified with functional magnetic resonance imaging scans in 11 patients with high-risk prostate cancer. Patients were treated using a dose-painting approach; the boost dose was limited to 86 Gy in 37 fractions, while keeping the rectal normal tissue complication probability to 5-6%. Rotational intensity-modulated radiotherapy was used with daily image guidance and fiducial markers. RESULTS: The median dose to the prostate (outside the boost volume) and urethra was 75.4 Gy/37 fractions (range 75.1-75.8 Gy), whereas the median boost dose was 83.4 Gy (range 79.0-87.4 Gy). The tumour control probability (TCP) (Marsden model) increased from 71% for the standard plans to 83.6% [76.6-86.8%] for the dose-painting boost plans. The mean (Lyman-Kutcher-Burman) normal tissue complication probability for rectal bleeding was 5.2% (range 3.3-6.2%) and 5.2% for faecal incontinence (range 3.6-7.8%). All patients tolerated the treatment well, with a low acute toxicity profile. At a median follow-up of 36 months (range 24-50) there was no grade 3 late toxicity. Two patients had grade 2 late urinary toxicity (urethral stricture, urinary frequency and urgency), one patient had grade 1 and one grade 2 late rectal toxicity. The mean prostate-specific antigen at follow-up was 0.81 ng/ml after stopping hormone therapy; one patient relapsed biochemically at 32 months (2.70 ng/ml). CONCLUSIONS: The toxicity for this radiobiological guided dose-painting protocol was low, but we have only treated a small cohort with limited follow-up time. The advantages of this treatment approach should be established in a clinical trial.
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Marcadores Fiduciales/normas , Neoplasias de la Próstata/radioterapia , Planificación de la Radioterapia Asistida por Computador/métodos , Radioterapia Guiada por Imagen/normas , Radioterapia de Intensidad Modulada/métodos , Anciano , Estudios de Seguimiento , Humanos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Clasificación del Tumor , Órganos en Riesgo , Estudios Prospectivos , Neoplasias de la Próstata/patología , Radiobiología/normas , Dosificación Radioterapéutica , Resultado del TratamientoRESUMEN
AIMS: To review the changes in permanent pacemaker implantation indications, pacing modes and patients' demographics over a 20-year period. METHODS AND RESULTS: We retrospectively retrieved data on patients who underwent first implantation of the pacemaker between 1-1-1991 and 31-12-2010. One thousand and nine (1,009) patients underwent a first pacemaker implantation during that period; 535 were men (53%), their mean age was 74.6±19.5 years; the highest rate of implanted pacemaker was in patients ranging in age from 70-79 years, however there was an increasing number of patients aged over 80 years. The median survival time after initial pacemaker implantation was 8 years. Syncope was the most common symptom (62.5%) and atrioventricular block was the most common electrocardiographic indication (56.4%) leading to pacemaker implantation. There was increased utilization of dual chamber and rate responsive pacemakers over the years. There was no difference regarding mode selection between genders. CONCLUSIONS: Pacemaker implantation rates have increased over a 20-year period. Dual chamber replaced most of the single ventricular chamber pacemaker and rate responsive pacemakers became the norm. The data of a small volume center are similar to those reported in pacemaker surveys of high volume pacemaker implantation centers. They confirm adherence to the published guidelines for pacing.
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Bloqueo Atrioventricular , Estimulación Cardíaca Artificial , Anciano , Anciano de 80 o más Años , Bloqueo Atrioventricular/complicaciones , Bloqueo Atrioventricular/epidemiología , Bloqueo Atrioventricular/terapia , Estimulación Cardíaca Artificial/métodos , Estimulación Cardíaca Artificial/estadística & datos numéricos , Femenino , Humanos , Israel/epidemiología , Masculino , Evaluación de Resultado en la Atención de Salud , Marcapaso Artificial/clasificación , Marcapaso Artificial/estadística & datos numéricos , Estudios Retrospectivos , Síncope/etiología , Síncope/terapiaAsunto(s)
Enfermedad de la Arteria Coronaria/diagnóstico , Vasos Coronarios/lesiones , Tomografía Computarizada por Rayos X/métodos , Heridas no Penetrantes/complicaciones , Adulto , Enfermedad de la Arteria Coronaria/etiología , Enfermedad de la Arteria Coronaria/patología , Estudios de Seguimiento , Humanos , MasculinoRESUMEN
INTRODUCTION: Life expectancy increases progressively and nonagenarians are a growing population. We report trends in pacing and long-term outcome in nonagenarians over a 20-year period in a single center compared with those of younger patients. METHODS: We retrospectively reviewed all the patients who underwent their first pacemaker implantation from January 1, 1991 to December 31, 2010 and were followed through December 31, 2013. RESULTS: During the study period, 1,009 patients underwent first pacemaker implantation: 45 patients were older than 90 years (mean age 92.5 ± 2.6) (4.5%); 21 were men. Battery replacement was performed in four patients in whom first implant was made at age ≥ 90 years (8.9%) and in 231 patients aged <90 (24%; P < 0.01). Syncope was the most common symptom leading to pacing, followed by dizziness and fatigue in all age groups; no significant difference of symptoms was found between patient age groups. In patients aged ≥ 90 atrioventricular block and atrial fibrillation with slow ventricular response were more frequent, while sick sinus syndrome and carotid sinus hypersensitivity were less frequent than in younger patients. Ventricular chamber pacemakers were implanted with significant growing frequency, according to the older patients' age. Neither the indication for pacemaker implantation nor pacing mode influenced survival. CONCLUSIONS: Nonagenarians are a growing population. Symptoms leading to pacing in patients aged ≥ 90 were similar to those of younger patients, but different frequency was found in the electrocardiographic indications. Ventricular chamber pacemakers were significantly more implanted than dual-chamber pacemakers but without negative survival influence.
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Marcapaso Artificial , Factores de Edad , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Estudios Retrospectivos , Factores de TiempoRESUMEN
OBJECTIVE: To study the impact of the interplay between respiration-induced tumour motion and multileaf collimator leaf movements in intensity-modulated radiotherapy (IMRT) as a function of number of fractions, dose rate on population mean tumour control probability ([Formula: see text]) using an in-house developed dose model. METHODS: Delivered dose was accumulated in a voxel-by-voxel basis inclusive of tumour motion over the course of treatment. The effect of interplay on dose and [Formula: see text] was studied for conventionally and hypofractionated treatments using digital imaging and communications in medicine data sets. Moreover, the effect of dose rate on interplay was also studied for single-fraction treatments. Simulations were repeated several times to obtain [Formula: see text] for each plan. RESULTS: The average variation observed in mean dose to the target volumes were -0.76% ± 0.36% for the 20-fraction treatment and -0.26% ± 0.68% and -1.05% ± 0.98% for the three- and single-fraction treatments, respectively. For the 20-fraction treatment, the drop in [Formula: see text] was -1.05% ± 0.39%, whereas for the three- and single-fraction treatments, it was -2.80% ± 1.68% and -4.00% ± 2.84%, respectively. By reducing the dose rate from 600 to 300 MU min(-1) for the single-fraction treatments, the drop in [Formula: see text] was reduced by approximately 1.5%. CONCLUSION: The effect of interplay on [Formula: see text] is negligible for conventionally fractionated treatments, whereas considerable drop in [Formula: see text] is observed for the three- and single-fraction treatments. Reduced dose rate could be used in hypofractionated treatments to reduce the interplay effect. ADVANCES IN KNOWLEDGE: A novel in silico dose model is presented to determine the impact of interplay effect in IMRT treatments on [Formula: see text].
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Neoplasias Pulmonares/radioterapia , Planificación de la Radioterapia Asistida por Computador/métodos , Radioterapia de Intensidad Modulada/métodos , Humanos , Movimiento (Física)RESUMEN
This is a case study of an 18 years old boy who lost consciousness during apneic underwater swimming. When cardiopulmonary resuscitation was initiated ventricular fibrillation was seen on cardiac monitoring. Bradycardia, atrial and ventricular premature beats are a known response to hyperventilation and apneic underwater diving. This case is the first documentation of ventricular fibritllation as a cause of sudden cardiac death during apneic underwater swimming.
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Apnea/complicaciones , Muerte Súbita Cardíaca/etiología , Hiperventilación/complicaciones , Fibrilación Ventricular/etiología , Adolescente , Humanos , Masculino , Natación/fisiologíaRESUMEN
BACKGROUND: Implantable cardioverter defibrillators (ICDs) and cardiac resynchronization therapy (CRT) reduce mortality in patients with heart failure (HF) and left ventricular dysfunction. However, their efficacy in patients with chronic kidney disease (CKD) is controversial. OBJECTIVE: We examined the association between renal dysfunction and clinical outcomes in patients undergoing ICD and CRT defibrillator (CRTD) implantation. METHODS: Data were collected from the Israeli ICD registry. Estimated glomerular filtration rate (eGFR) at implantation was assessed using the modification of diet in renal disease formula. Primary outcome was all-cause mortality. Secondary outcomes included the composite endpoints of death or HF and death or ventricular arrhythmias (ventricular tachycardia/ventricular fibrillation [VT/VF]); any hospitalizations; first appropriate and inappropriate ICD therapy. RESULTS: During the study period (July 2010-November 2012), 2,811 patients were implanted with ICD or CRTD. One-year follow-up data were available for 730 ICD patients and 453 CRTD patients. Patients with eGFR < 30 mL/minute/1.73 m(2) (n = 54, 4.6%) were older, had a higher prevalence of diabetes, hypertension, or ischemic heart disease. eGFR <30 mL/minute/1.73 m(2) was associated with increased mortality risk in ICD (HR 5.4; 95% CI 1.5-19.2), but not in CRTD patients (HR 0.9; 95% CI 0.1-7.5). Renal dysfunction was associated with the composite endpoints of death or HF and death or VT/VF in ICD, but not in CRTD patients. Mean eGFR during follow-up decreased by 8.0 ± 4.3 mL/minute/1.73 m(2) in ICD patients (P = 0.06) and by 1.8 ± 1.3 mL/minute/1.73 m(2) in patients with CRTD (P = 0.2). CONCLUSION: Based on this retrospective analysis, CKD is associated with adverse prognosis after ICD implantation, but not after CRTD implantation. GFR decreased in patients with ICD, but not in CRTD patients.
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Terapia de Resincronización Cardíaca/efectos adversos , Desfibriladores Implantables/efectos adversos , Riñón/fisiopatología , Complicaciones Posoperatorias/etiología , Anciano , Femenino , Humanos , Israel , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/epidemiología , Estudios Prospectivos , Sistema de Registros , Estudios Retrospectivos , Resultado del TratamientoRESUMEN
BACKGROUND: Axillary vein puncture has been demonstrated to be an effective method for pacemaker and defibrillator leads implantation, without the complications encountered with the standard intrathoracic approach. OBJECTIVE: Different techniques have been adopted for the cannulation of the axillary vein. We report our experience using the outer edge of the first rib below the inferior border of the clavicle as fluoroscopic landmark. METHOD: A subcutaneous pocket is created 1-cm medially and parallel to the delto-pectoral groove and 2 cm below the clavicle. An 18-gauge needle from the upper border of the pocket is directed perpendicularly to the outer edge of the first rib just below the inferior border of the clavicle. If the vein is not entered, the needle is withdrawn and the puncture is repeated with slight variations of needle direction for a maximum of four to five times, then contrast-guided vein puncture is performed. Upon successful vein puncture, a guidewire is inserted and positioned in the superior vena cava. The remainder of the implantation is carried out in a routine manner. RESULTS: The axillary vein was successfully cannulated without venography in 172 of 182 consecutive patients (94.5%); the vein could not be found in 10 patients (5.5%): in these patients the vein was successfully cannulated after venography performance. No pneumothorax, hemothorax, or brachial plexus injury occurred. CONCLUSIONS: Our approach of axillary venipunture using fluoroscopic landmark, without contrast venography, is simple, safe, and effective.
Asunto(s)
Vena Axilar/cirugía , Desfibriladores Implantables/estadística & datos numéricos , Electrodos Implantados/estadística & datos numéricos , Marcapaso Artificial/estadística & datos numéricos , Implantación de Prótesis/métodos , Punciones/estadística & datos numéricos , Radiografía Intervencional/estadística & datos numéricos , Adulto , Anciano , Anciano de 80 o más Años , Puntos Anatómicos de Referencia/diagnóstico por imagen , Vena Axilar/diagnóstico por imagen , Humanos , Israel/epidemiología , Persona de Mediana Edad , Flebografía/estadística & datos numéricos , Prevalencia , Punciones/métodos , Reproducibilidad de los Resultados , Factores de Riesgo , Sensibilidad y Especificidad , Resultado del TratamientoRESUMEN
The objective of this work was to compare the effectiveness of conventional technologies (adsorption on activated carbon, AC, and ozonation) and technologies based on advanced oxidation processes, AOPs, (UV/H(2)O(2), O(3)/AC, O(3)/H(2)O(2)) to remove phthalates from aqueous solution (ultrapure water, surface water and wastewater). Diethyl phthalate (DEP) was chosen as a model pollutant because of its high water solubility (1,080 mg/L at 293 K) and toxicity. The activated carbons showed a high adsorption capacity to adsorb DEP in aqueous solution (up to 858 mg/g), besides the adsorption mechanism of DEP on activated carbon is governed by dispersive interactions between π electrons of its aromatic ring with π electrons of the carbon graphene planes. The photodegration process showed that the pH solution does not significantly affect the degradation kinetics of DEP and the first-order kinetic model satisfactorily fitted the experimental data. It was observed that the rate of decomposition of DEP with the O(3)/H(2)O(2) and O(3)/AC systems is faster than that with only O(3). The technologies based on AOPs (UV/H(2)O(2), O(3)/H(2)O(2), O(3)/AC) significantly improve the degradation of DEP compared to conventional technologies (O(3), UV). AC adsorption, UV/H(2)O(2), O(3)/H(2)O(2), and O(3)/AC showed a high yield to remove DEP; however, the disadvantage of AC adsorption is its much longer time to reach maximum removal. The best system to treat water (ultrapure and natural) polluted with DEP is the O(3)/AC one since it achieved the highest DEP degradation and TOC removal, as well as the lower water toxicity.
Asunto(s)
Carbón Orgánico/química , Oxidantes/química , Ácidos Ftálicos/aislamiento & purificación , Rayos Ultravioleta , Contaminantes Químicos del Agua/aislamiento & purificación , Purificación del Agua/métodos , Adsorción , Peróxido de Hidrógeno/química , Cinética , Oxidación-Reducción , Ozono/química , Ácidos Ftálicos/química , Ácidos Ftálicos/efectos de la radiación , Soluciones , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/efectos de la radiaciónRESUMEN
OBJECTIVE: This work explores the biological basis of a mechanistic model of radiation-induced lung damage; uniquely, the model makes a connection between the cellular radiobiology involved in lung irradiation and the full three-dimensional distribution of radiation dose. METHODS: Local tissue damage and loss of global organ function, in terms of radiation pneumonitis (RP), were modelled as different levels of radiation injury. Parameters relating to the former could be derived from the local dose-response function, and the latter from the volume effect of the organ. The literature was consulted to derive information on a threshold dose and volume-effect mechanisms. RESULTS: Simulations of local tissue damage supported the alveolus as a functional subunit (FSU) which can be regenerated from a single surviving stem cell. A moderate interpatient variation in stem cell radiosensitivity (15%) resulted in a great variation in tissue response between 8 and 20 Gy. The threshold of FSU inactivation within a critical functioning volume leading to RP was found to be approximately 47% and the degree of health status variation (influencing the volume effect) in a population was estimated at 25%. CONCLUSION: This work has shown that it is possible to make sense of the way the lung responds to radiation by modelling RP mechanistically, from cell death to tissue damage to loss of organ function. ADVANCES IN KNOWLEDGE: Simulations were able to provide parameter values, currently not available in the literature, related to the response of the lung to irradiation.