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1.
Am J Ophthalmol Case Rep ; 26: 101512, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35496762

RESUMEN

Purpose: To report successful ring-shaped iodine-125 plaque brachytherapy for conjunctival melanoma. Observations: Eye Physics (EP) plaque brachytherapy, designed with Plaque Simulator software, proved to be an effective treatment modality with some corneal irritation and no recurrence at 12-months post radiation. Conclusion and importance: Management of conjunctival melanoma is complicated by the lack of gold standard adjuvant treatments. I-125 EP plaque brachytherapy represents a viable option for these malignancies. Specifically, ring-shaped plaque geometries allow for targeted radiotherapy.

2.
Nature ; 599(7885): 436-441, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34732894

RESUMEN

The state of somatic energy stores in metazoans is communicated to the brain, which regulates key aspects of behaviour, growth, nutrient partitioning and development1. The central melanocortin system acts through melanocortin 4 receptor (MC4R) to control appetite, food intake and energy expenditure2. Here we present evidence that MC3R regulates the timing of sexual maturation, the rate of linear growth and the accrual of lean mass, which are all energy-sensitive processes. We found that humans who carry loss-of-function mutations in MC3R, including a rare homozygote individual, have a later onset of puberty. Consistent with previous findings in mice, they also had reduced linear growth, lean mass and circulating levels of IGF1. Mice lacking Mc3r had delayed sexual maturation and an insensitivity of reproductive cycle length to nutritional perturbation. The expression of Mc3r is enriched in hypothalamic neurons that control reproduction and growth, and expression increases during postnatal development in a manner that is consistent with a role in the regulation of sexual maturation. These findings suggest a bifurcating model of nutrient sensing by the central melanocortin pathway with signalling through MC4R controlling the acquisition and retention of calories, whereas signalling through MC3R primarily regulates the disposition of calories into growth, lean mass and the timing of sexual maturation.


Asunto(s)
Desarrollo Infantil/fisiología , Estado Nutricional/fisiología , Pubertad/fisiología , Receptor de Melanocortina Tipo 3/metabolismo , Maduración Sexual/fisiología , Adolescente , Anciano de 80 o más Años , Animales , Niño , Ciclo Estral/genética , Ciclo Estral/fisiología , Femenino , Homocigoto , Humanos , Hipotálamo/citología , Hipotálamo/fisiología , Factor I del Crecimiento Similar a la Insulina/metabolismo , Masculino , Melanocortinas/metabolismo , Menarquia/genética , Menarquia/fisiología , Ratones , Fenotipo , Pubertad/genética , Receptor de Melanocortina Tipo 3/deficiencia , Receptor de Melanocortina Tipo 3/genética , Maduración Sexual/genética , Factores de Tiempo , Aumento de Peso
3.
J Sci Food Agric ; 101(15): 6289-6299, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33966279

RESUMEN

BACKGROUND: Tomato is one of the widely cultivated crops worldwide that is affected by several pests, such as fungi (Fusarium oxysoporum, Alternaria solani), bacteria (Pectobacterium carotovorum) and weeds (Cyperus iria L., Amaranthus spinosus). A growing interest has emerged for developing plant-derived pesticidal compounds to counteract these pests. One attractive alternative is to use barnyard grass (Echinochloa crus-galli), known to be widely resistant to synthetic herbicides, as a potential biopesticide compound source. RESULTS: Phytochemical screening of the crude extract showed that phenolic compounds were the most abundant component present in barnyard grass. The crude extract was evaluated for antifungal, antibacterial and herbicidal activities. Bioassays showed inhibition against F. oxysporum (10.73 ± 1.30%) and A. solani (20.47 ± 3.51%), the causative agent of Fusarium rot and early blight disease in tomato, respectively. Antibacterial activity against P. carotovorum gave a mean zone of inhibition (paper disc diffusion assay) of 17.00 ± 1.00 mm and an IC50 (dose-response assay) of 2.26 mg mL-1 was observed. Dose-responsive herbicidal activity on the lettuce seed germination bioassay produced an IC50 of 459.30 ppm. Selectivity studies showed inhibition towards C. iria and A. spinosus with no effect on tomato. Lastly, bioassay-guided fractionation coupled with untargeted metabolomics studies using ultra-performance liquid chromatography with diode array detection-tandem mass spectrometry mass analyses revealed loliolide and tricin as the putative metabolites present in barnyard grass. CONCLUSION: To date, this is the first reported study on using barnyard grass as a potential alternative biopesticide against tomato pests such as fungi, bacteria and weeds. © 2021 Society of Chemical Industry.


Asunto(s)
Alternaria/efectos de los fármacos , Echinochloa/química , Fungicidas Industriales/farmacología , Fusarium/efectos de los fármacos , Enfermedades de las Plantas/microbiología , Extractos Vegetales/farmacología , Solanum lycopersicum/microbiología , Herbicidas/farmacología , Lactuca/efectos de los fármacos , Hojas de la Planta/química
4.
Environ Sci Technol ; 51(11): 5978-5988, 2017 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-28457132

RESUMEN

For the first time, trapped ion mobility spectrometry (TIMS) in tandem with Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) is applied to the analysis of the low energy water accommodated fraction (WAF) of a crude oil as a function of the exposure to light. The TIMS-FT-ICR MS analysis provided, in addition to the heteroatom series identification, new insights into the WAF isomeric complexity (e.g., [m/z; chemical formula; collision cross section] data sets) for a better evaluation of the degree of chemical and structural photoinduced transformations. Inspection of the [m/z; chemical formula; collision cross section] data sets shows that the WAF composition changes as a function of the exposure to light in the first 115 h by initial photosolubilization of HC components and their photo-oxidation up to O4-5 of mainly high double bond equivalence species (DBE > 9). The addition of high resolution TIMS (resolving power of 90-220) to ultrahigh resolution FT-ICR MS (resolving power over 400k) permitted the identification of a larger number of molecular components in a single analysis (e.g., over 47k using TIMS-MS compared to 12k by MS alone), with instances of over 6-fold increase in the number of molecular features per nominal mass due to the WAF isomeric complexity. This work represents a stepping stone toward a better understanding of the WAF components and highlights the need for better experimental and theoretical approaches to characterize the WAF structural diversity.


Asunto(s)
Petróleo , Contaminantes Químicos del Agua , Análisis de Fourier , Iones , Espectrometría de Masas , Espectroscopía Infrarroja por Transformada de Fourier , Agua
5.
Mar Pollut Bull ; 105(1): 110-9, 2016 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-26947926

RESUMEN

Among the discoveries of the Deepwater Horizon blowout was the so-called "sub-surface plume"; herein termed the "oil-trapping layer". Hydrocarbons were found positioned at ~1100-1300m with thickness ~100-150m and moving horizontally to the SW in a vertically stratified layer at the junction of the cold abyssal water and the permanent thermocline. This study focuses on its formation process and fate of the hydrocarbons within. The originality of this work to the field is two-fold, first it provides a conceptual framework which places layer origin in the context of a horizontal "intrusion" from the near-field, vertical, blow-out plume and second, it offers a theoretical model for the hydrocarbon chemicals within the horizontal layer as it moves far-afield. The model quantifies the oil-material fractionation process for the soluble and fine particle. The classical Box model, retrofitted with an internal gradient, the "G-Box", allows an approach that includes turbulent eddy diffusion coupled with droplet rise velocity and reactive decay to produce a simple, explicit, transparent, algebraic model with few parameters for the fate of the individual fractions. Computations show the soluble and smallest liquid droplets moving very slowly vertically through the layer appearing within the trapping layer at low concentration with high persistence. The larger droplets move-through this trapping zone quickly, attain high concentrations, and eventually form the sea surface slick. It impacts the field of oil spill engineering science by providing the conceptual idea and the algorithms for projecting the quantities and fractions of oil-material in a deep water, horizontal marine current being dispersed and moving far afield. In the field of oil spill modeling this work extends the current generation near-field plume source models to the far-field. The theory portrays the layer as an efficient oil-material trap. The model-forecasted concentration profiles for alkanes and aromatics against the available field data support the proposed theory and the resulting model.


Asunto(s)
Hidrocarburos/análisis , Modelos Químicos , Contaminación por Petróleo/análisis , Petróleo/análisis , Contaminantes Químicos del Agua/análisis , Fraccionamiento Químico , Monitoreo del Ambiente , Golfo de México
6.
Food Chem ; 152: 349-54, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24444947

RESUMEN

Differential scanning calorimetry (DSC), headspace oxygen and solid phase microextraction gas chromatography and peroxide value were used to evaluate the effect of riboflavin on the photo-oxidation of vegetable oil in salad dressing. Salad dressings with 0, 5, 20, 50 and 100 ppm added riboflavin were stored under light (2500 lux) at 25 °C for 5 days. Crystallisation peaks in the DSC thermograms of the oil samples shifted to lower temperatures and enthalpies decreased as the storage time increased. As the riboflavin concentrations increased from 0 to 100 ppm, the crystallisation enthalpies increased from 27 to 31 J/g and the maximum crystallisation temperature increased from -64 to -62 °C during the 5 day storage. Headspace oxygen depletion rates, the formation of volatile compounds and peroxide values of the salad dressing samples simultaneously decreased with the addition of riboflavin, showing that riboflavin protected the oil in salad dressing from photo-oxidation.


Asunto(s)
Antioxidantes/química , Alimentos/efectos de la radiación , Aceites de Plantas/química , Riboflavina/química , Almacenamiento de Alimentos , Calor , Luz , Oxidación-Reducción/efectos de la radiación
7.
Anal Chem ; 86(4): 2019-24, 2014 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-24428664

RESUMEN

In the present paper, trapped ion mobility spectrometry (TIMS) and theoretical calculations have been used to study carotenoid geometrical motifs generated by photoisomerization from the all-trans geometry. Multiple geometric isomers of the carotenoids lutein and zeaxanthin were separated using TIMS (R > 110) for [M](+), [M + H](+), and [M - 18](+) molecular species. Comparison of observed cross sections with those obtained from molecular dynamics calculations showed that the number of cis double bonds and s-cis single bonds in the polyene chain determine the topology space of the carotenoid. The intensities of IMS signals are correlated with the relative stability of these geometric isomers.1,2 The most stable isomer is the all-trans geometry regardless of the ionization state ([M - 18](+), [M](+), and [M + H](+)), and structural stability decreases with the increasing number of cis and/or s-cis bonds in the polyene chain.


Asunto(s)
Carotenoides/química , Carotenoides/aislamiento & purificación , Polienos/química , Polienos/aislamiento & purificación , Luteína/química , Luteína/aislamiento & purificación , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Estructura Terciaria de Proteína , Estereoisomerismo , Xantófilas/química , Xantófilas/aislamiento & purificación , Zeaxantinas
8.
J Phys Act Health ; 5(3): 445-55, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-18579921

RESUMEN

BACKGROUND: This study was designed to develop an evidence- and community based falls prevention program -- Tai Chi: Moving for Better Balance. METHODS: A mixed qualitative and quantitative approach was used to develop a package of materials for program implementation and evaluation. The developmental work was conducted in 2 communities in the Pacific Northwest. Participants included a panel of experts, senior service program managers or activity coordinators, and older adults. Outcome measures involved program feasibility and satisfaction. RESULTS: Through an iterative process, a program package was developed. The package contained an implementation plan and class training materials (ie, instructor's manual, videotape, and user's guidebook). Pilot testing of program materials showed that the content was appropriate for the targeted users (community-living older adults) and providers (local senior service organizations). A feasibility survey indicated interest and support from users and providers for program implementation. A 2-week pilot evaluation showed that the program implementation was feasible and evidenced good class attendance, high participant satisfaction, and interest in continuing Tai Chi. CONCLUSIONS: The package of materials developed in this study provides a solid foundation for larger scale implementation and evaluation of the program in community settings.


Asunto(s)
Accidentes por Caídas/prevención & control , Servicios de Salud Comunitaria , Promoción de la Salud , Actividad Motora , Desarrollo de Programa , Evaluación de Programas y Proyectos de Salud , Mercadeo Social , Taichi Chuan , Factores de Edad , Anciano , Anciano de 80 o más Años , Recolección de Datos , Estudios de Factibilidad , Femenino , Humanos , Masculino , Oregon , Proyectos Piloto , Investigación Cualitativa , Estados Unidos
9.
Am J Public Health ; 98(7): 1195-8, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18511723

RESUMEN

Tai chi--moving for better balance, a falls-prevention program developed from a randomized controlled trial for community-based use, was evaluated with the re-aim framework in 6 community centers. The program had a 100% adoption rate and 87% reach into the target older adult population. All centers implemented the intervention with good fidelity, and participants showed significant improvements in health-related outcome measures. This evidence-based tai chi program is practical to disseminate and can be effectively implemented and maintained in community settings.


Asunto(s)
Accidentes por Caídas/prevención & control , Educación en Salud/métodos , Promoción de la Salud/métodos , Taichi Chuan , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Evaluación de Resultado en la Atención de Salud , Equilibrio Postural/fisiología , Evaluación de Programas y Proyectos de Salud , Ensayos Clínicos Controlados Aleatorios como Asunto
10.
Am J Clin Hypn ; 49(1): 7-12, 2006 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16889358

RESUMEN

In 1844, an obscure and little-remembered American theorist, A. Yorke (no further identification is available), published a theory of mesmerism based on absorption, i.e., mental concentration. Unlike Mesmer's conceptualization of animal magnetism as a biological fluid, however, Yorke's theory emphasized the psychological importance of the mutual interaction between mesmerist and subject. This paper discusses the latter's theory of absorption as an important development in neo-mesmerism, the circumstances that led him to his conclusions, and his role in advancing our knowledge of the historical origins of modern hypnosis.


Asunto(s)
Personajes , Hipnosis/historia , Teoría Psicológica , Historia del Siglo XIX , Humanos , Estados Unidos
11.
J Cataract Refract Surg ; 31(7): 1396-402, 2005 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16105613

RESUMEN

PURPOSE: To characterize a rabbit model of Mycobacterium chelonae keratitis after lamellar keratectomy and assess the effectiveness of fluoroquinolone therapy. SETTING: University Laboratory, University of California, Irvine, California, USA. METHODS: Twenty-eight New Zealand white rabbits had unilateral lamellar keratectomy with placement of 2.5 x 10(5) colony-forming units of log-phase M chelonae under each flap. Eyes (7 per group) were randomized and treated with sterile balanced salt solution, gatifloxacin 0.3%, ciprofloxacin 0.3%, or levofloxacin 0.5% 4 times daily. Two masked observers examined all eyes on days 2, 5, and 7 and weekly for 4 weeks. Severity of disease and bacterial culture results were the main outcomes measured. The means and standard deviations were calculated, and differences between the groups were statistically analyzed. RESULTS: All eyes developed clinical disease. At the time the rabbits were killed, eyes treated with balanced salt solution, ciprofloxacin, levofloxacin, and gatifloxacin were culture positive in 6 (85.7%), 7 (100%), 6 (85.7%), and 3 (42.9%) of 7 eyes per group, respectively. Frequency of positive culture and the severity of clinical disease in gatifloxacin-treated eyes were significantly less (P < .05) than in the other groups combined. CONCLUSIONS: The rabbit model of M chelonae keratitis was successfully developed in our study. A fourth-generation quinolone (gatifloxacin) showed the best performance among the fluoroquinolones tested in our experimental approach. The fourth-generation fluoroquinolone, gatifloxacin, could be effectively used for the treatment of mycobacterial keratitis.


Asunto(s)
Antiinfecciosos/uso terapéutico , Trasplante de Córnea , Infecciones Bacterianas del Ojo/tratamiento farmacológico , Fluoroquinolonas/uso terapéutico , Queratitis/tratamiento farmacológico , Infecciones por Mycobacterium no Tuberculosas/tratamiento farmacológico , Mycobacterium chelonae/fisiología , Animales , Ciprofloxacina/uso terapéutico , Recuento de Colonia Microbiana , Córnea/microbiología , Modelos Animales de Enfermedad , Infecciones Bacterianas del Ojo/microbiología , Gatifloxacina , Queratitis/microbiología , Levofloxacino , Infecciones por Mycobacterium no Tuberculosas/microbiología , Ofloxacino/uso terapéutico , Conejos
12.
Int J Clin Exp Hypn ; 52(2): 113-31, 2004 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15115058

RESUMEN

There has been a gradual evolution of the important construct of transference from ancient to modern times. Long before Franz Anton Mesmer, there were philosophers, theorists, and health professionals who emphasized the impact of interpersonal relationships on well-being and illness. While basically conceptualizing animal magnetism as a dynamic physical fluid, Mesmer was also aware of the impact of rapport and affect in the enhancement of magnetic treatment. Later neo-mesmerists, notably Puységur and Deleuze, built on such theories. That emphasis continued through the 19th century to the time of Freud, whose construct of transference was derived from his personal experience with hypnosis and which has since become an integral part of modern psychodynamic theory and treatment.


Asunto(s)
Hipnosis/historia , Psicoanálisis/historia , Teoría Psicoanalítica , Transferencia Psicológica , Austria , Alemania , Historia del Siglo XVIII , Historia del Siglo XIX , Historia del Siglo XX , Humanos
13.
Am J Ophthalmol ; 136(1): 76-81, 2003 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-12834673

RESUMEN

PURPOSE: To assess the effectiveness of a fourth-generation fluoroquinolone for prophylaxis against multiple drug-resistant staphylococcal keratitis after lamellar keratectomy in a rabbit model. DESIGN: Experimental study. METHODS: Twenty-eight New Zealand white rabbits underwent unilateral lamellar keratectomy using a manual microkeratome followed by the placement of 1000 colony-forming units (CFUs) of log-phase Staphylococcus aureus bacteria under each flap. Eyes (seven in each group) were randomized and treated with one of the following agents: sterile balanced salt solution, gatifloxacin (0.3%), ciprofloxacin (0.3%) or levofloxacin (0.5%) immediately and 6, 12, and 18 hours after surgery. Inflammation was graded by two masked observers at 24 and 48 hours, and the presence or absence of infectious infiltrates was determined. The means and standard deviations were calculated, and differences among the groups were statistically analyzed. RESULTS: There were no flap complications encountered during surgery. Eyes treated with ciprofloxacin, levofloxacin, and balanced salt solution developed infectious infiltrates in five of seven eyes per group. Gatifloxacin-treated eyes did not develop clinical infection and exhibited lower mean inflammation scores (P <.01 compared with the other groups). CONCLUSION: The fourth-generation fluoroquinolone, gatifloxacin, is an effective prophylaxis against the development of keratitis after lamellar keratectomy in rabbits with an organism resistant to methicillin, levofloxacin, and ciprofloxacin.


Asunto(s)
Antiinfecciosos/uso terapéutico , Farmacorresistencia Bacteriana Múltiple , Infecciones Bacterianas del Ojo/tratamiento farmacológico , Fluoroquinolonas , Queratitis/tratamiento farmacológico , Queratomileusis por Láser In Situ/efectos adversos , Infecciones Estafilocócicas/tratamiento farmacológico , Animales , Ciprofloxacina/uso terapéutico , Recuento de Colonia Microbiana , Sustancia Propia/microbiología , Modelos Animales de Enfermedad , Infecciones Bacterianas del Ojo/microbiología , Gatifloxacina , Queratitis/microbiología , Levofloxacino , Ofloxacino/uso terapéutico , Conejos , Infecciones Estafilocócicas/microbiología , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/aislamiento & purificación , Staphylococcus aureus/fisiología , Colgajos Quirúrgicos/microbiología
14.
Brachytherapy ; 2(4): 229-39, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-15062131

RESUMEN

PURPOSE: The purpose of this study was to search for an optimal radiation dose in the treatment of patients with uveal melanoma using 125I episcleral plaque radiotherapy (EPRT) and episcleral hyperthermia (HT). METHODS AND MATERIALS: From 1991-1998, 35 patients with uveal melanoma were enrolled in a phase II prospective randomized trial of 125I EPRT combined with episcleral HT. Two groups were closely matched for pre-treatment patient and tumor characteristics. Group 1: N = 16, and Group 2: N = 19. The median dose to the tumor apex for Group 1 was 80.0 Gy and 60.8 Gy for Group 2. Episcleral HT was given once for 45 min immediately prior to EPRT with a median temperature of 44 degrees C for both groups. The median follow-up was 5.5 years for Group 1 and 5.3 years for Group 2. RESULTS: The median tumor height decreased 1.7 mm for patients of both groups. The 5- and 8-year probability of local recurrence was 33% for Group 1, and 25% for Group 2, p = 0.73. The 5-year probability of DFS was 54% for Group 1 and 67% for Group 2, p = 0.51. The 5- and 8-year overall survival was 68% and 34%, respectively, for Group 1, and 83% and 50%, respectively, for Group 2, p = 0.60. The rate of distant metastasis at 5- and 8-years for Group 1 was 29% and 62%, respectively, and 17% and 17%, respectively, for Group 2, p = 0.18. The incidence of enucleation was 4 (25%) in Group 1 vs. 4 (22%) in Group 2. The incidence of late complications was similar in either treatment group. The ambulatory visual acuity (> 5/200) at last follow-up was slightly better in Group 2 (80%) than Group 1 (64%). CONCLUSIONS: Treatment outcomes were similar despite a 25% difference in radiation dose. In view of these findings and in an attempt to reduce the incidence of late treatment toxicity a still lower radiation dose in combination with HT needs to be studied. The reported outcomes need to be evaluated with caution due to the small number of patients in this study.


Asunto(s)
Melanoma/radioterapia , Neoplasias de la Úvea/radioterapia , Adulto , Anciano , Supervivencia sin Enfermedad , Femenino , Humanos , Hipertermia Inducida , Radioisótopos de Yodo/uso terapéutico , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Dosificación Radioterapéutica , Análisis de Supervivencia , Resultado del Tratamiento
15.
Am J Clin Hypn ; 45(1): 3-10, 2002 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-12116612

RESUMEN

The 1956 publication of The Search for Bridey Murphy was a noteworthy event for the field of hypnosis. This internationally best selling book, written for lay readers, described several recorded sessions of alleged time-regression to a prior life nearly two centuries before 1956. While subsequent investigations disproved that claim, there were a number of important implications for the science and practice of hypnosis. Although it was concluded that the Bridey Murphy interviews were products of cryptomnesia, the book was a significant factor associated with a resurgence of public and professional interest in the modality.


Asunto(s)
Hipnosis , Recuerdo Mental , Parapsicología , Regresión Psicológica , Adulto , Femenino , Humanos , Sugestión , Transferencia Psicológica
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