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1.
Oper Neurosurg (Hagerstown) ; 25(6): 529-537, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37655877

RESUMO

BACKGROUND AND OBJECTIVES: Stereotactic radiosurgery (SRS) is increasingly applied to treat meningiomas, attributable to their increased incidence in older individuals at greater surgical risk. To evaluate the effectiveness of treatment with linear accelerator (LINAC)-based stereotactic radiosurgery in skull base meningiomas as either primary treatment or postresection adjuvant therapy. METHODS: This study included 241 patients diagnosed with skull base meningiomas treated by single-dose SRS, with a median age of 59 years. SRS was primary treatment in 68.1% (n = 164) and adjuvant treatment in 31.9% (n = 77), using LINAC (Varian 600, 6 MeV). The median tumor volume was 3.2 cm 3 , and the median coverage dose was 14 Gy. Bivariate and multivariate analyses were performed to determine predictive factors for tumor progression, clinical deterioration, and complications. Kaplan-Meier analysis was used for survival analysis. RESULTS: After the median follow-up of 102 months, the tumor control rate was 91.2% (n = 220). Progression-free survival rates were 97.07%, 90.1%, and 85.7% at 5, 10, and 14 years, respectively. Clinical improvement was observed in 56 patients (23.2%). In multivariate analysis, previous surgery (hazard ratio 3.8 [95%CI 1.136-12.71], P = .030) and selectivity (hazard ratio .21 [95%CI 0.066-0.677], P = .009) were associated with tumor progression and increased maximum dose (odds ratio [OR] 4.19 [95% CI 1.287-13.653], P = .017) with clinical deterioration. The permanent adverse radiation effect rate was 6.2% (n = 15) and associated with maximum brainstem dose >12.5 Gy (OR 3.36 [95% CI .866-13.03], P = .08) and cerebellopontine angle localization (OR 3.93 [95% CI 1.29-11.98], P = .016). CONCLUSION: Treatment of skull base meningiomas with single-dose SRS using LINAC is effective over the long term. Superior tumor control is obtained in patients without previous surgery. Adverse effects are related to localization in the cerebellopontine angle, and maximum brainstem radiation dose was >12.5 Gy.


Assuntos
Deterioração Clínica , Neoplasias Meníngeas , Meningioma , Radiocirurgia , Neoplasias da Base do Crânio , Humanos , Idoso , Pessoa de Meia-Idade , Meningioma/radioterapia , Meningioma/cirurgia , Resultado do Tratamento , Estudos Retrospectivos , Neoplasias da Base do Crânio/radioterapia , Neoplasias da Base do Crânio/cirurgia , Neoplasias Meníngeas/radioterapia , Neoplasias Meníngeas/cirurgia , Neoplasias Meníngeas/patologia , Base do Crânio/cirurgia , Base do Crânio/patologia
2.
Neurocirugia (Astur : Engl Ed) ; 34(6): 283-291, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36842609

RESUMO

OBJECTIVES: To evaluate the efficacy of treatment with linear accelerator-based stereotactic radiosurgery (LINAC) in cerebellopontine angle meningiomas. METHODS: We analyzed 80 patients diagnosed with cerebellopontine angle meningiomas between 2001 and 2014, treated with stereotactic radiosurgery (SRS), of whom 81.9% (n=68) were women, with an average age of 59.1 years (32-79). SRS was applied as primary treatment in 83.7% (n=67) and in 16.3% (n=13) as an adjuvant treatment to surgery. SRS treatment was provided using LINAC (Varian 600, 6MeV) with M3 micromultilamines (brainLab) and stereotactic frame. The average tumor volume was 3.12cm3 (0.34-10.36cm3) and the coverage dose was 14Gy (12-16Gy). We performed a retrospective descriptive analysis and survival analysis was performed with the Kaplan-Meier method and multivariate analysis to determine those factors predictive of tumor progression or clinical improvement. RESULTS: After an average follow-up period of 86.9 months (12-184), the tumor control rate was 92.8% (n=77). At the end of the study, there was an overall reduction in tumor volume of 32.8%, with an average final volume of 2.11cm3 (0-10.35cm3). The progression-free survival rate at 5, 10 and 12 years was 98%, 95% and 83.3% respectively. The higher tumor volume (p=0.047) was associated with progression. There was clinical improvement in 26.5% (n=21) of cases and clinical worsening in 16.2% (n=13). Worsening is related to the radiation dose received by the brainstem (p=0.02). Complications were 8.7% (7 cases) of hearing loss, 5% (4 cases) of brain radionecrosis, and 3.7% (3 cases) of cranial nerve V neuropathy. Hearing loss was related to initial tumor size (p=0.033) and maximum dose (p=0.037). The occurrence of radionecrosis with the maximum dose (p=0.037). CONCLUSIONS: Treatment of cerebellopontine angle meningiomas with single-dose SRS using LINAC is effective in the long term. Better tumor control rates were obtained in patients with small lesions.


Assuntos
Perda Auditiva , Neoplasias Meníngeas , Meningioma , Neuroma Acústico , Radiocirurgia , Humanos , Feminino , Pessoa de Meia-Idade , Masculino , Meningioma/radioterapia , Meningioma/cirurgia , Meningioma/complicações , Radiocirurgia/efeitos adversos , Radiocirurgia/métodos , Resultado do Tratamento , Neoplasias Meníngeas/radioterapia , Neoplasias Meníngeas/cirurgia , Neoplasias Meníngeas/complicações , Estudos Retrospectivos , Ângulo Cerebelopontino/patologia , Seguimentos , Perda Auditiva/complicações , Perda Auditiva/cirurgia , Neuroma Acústico/radioterapia , Neuroma Acústico/cirurgia
3.
J Alzheimers Dis ; 86(2): 861-875, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35147532

RESUMO

BACKGROUND: There is high prevalence of neuropsychiatric symptoms (NPS) among dementia patients. NPS are correlated with dementia progression, functional decline, early institutionalization, and death. There is scarce evidence on the progression of NPS in the latest stages of dementia. OBJECTIVE: To describe the prevalence of NPS in mild-moderate to severe dementia and to reveal the progression of each NPS over time. METHODS: We studied 317 patients (77.3% female, average age: 81.5 years) with a DSM-IV-TR diagnosis of dementia. This is a cross-sectional, and a prospective longitudinal study with 78-month follow-up. We assessed cognitive status (Mini-Mental State Examination and Severe Mini-Mental State Examination), dementia severity (Global Deterioration Scale and Clinical Dementia Rating), and psychopathological measures (Neuropsychiatric Inventory, APADEM-Nursing Home, Apathy Inventory, Cornell Scale for Depression in Dementia, and Cohen-Mansfield Agitation Inventory). RESULTS: Overall prevalence of NPS was 94.6%, being apathy the most prevalent (66.7%) and the one whose severity increased the most with progression of dementia. Agitation/aggression, irritability, and sleeping and eating disorders also increased over time. Delusions and depressive symptoms decreased in severity with disease progression. In severe dementia, female displayed more depressive symptoms and eating disorders, while male displayed more agitation/aggression and sleep disturbances. CONCLUSION: NPS in dementia follow a heterogeneous course. Apathy is the most prevalent NPS and the one that worsens most significantly over time. The course of some NPS differs between sexes. Further research is required to understand the evolution of NPS at advanced stages of dementia.


Assuntos
Demência , Agitação Psicomotora , Idoso de 80 Anos ou mais , Estudos Transversais , Demência/psicologia , Feminino , Humanos , Estudos Longitudinais , Masculino , Testes Neuropsicológicos , Estudos Prospectivos , Agitação Psicomotora/epidemiologia
4.
Psicol. conduct ; 24(3): 389-403, sept.-dic. 2016. tab, graf
Artigo em Espanhol | IBECS | ID: ibc-162331

RESUMO

El objetivo de esta investigación es estudiar la eficacia de un programa de tratamiento cognitivo conductual grupal en pacientes con diagnóstico de trastorno adaptativo. La muestra está compuesta por 102 pacientes de dos Unidades de Salud Mental y un centro de Atención Primaria de Valencia (España). El tratamiento consistió en una terapia grupal cognitivo conductual de ocho sesiones de una hora y media de duración, con una frecuencia semanal. Se realizaron mediciones pre y postratamiento y un seguimiento a los tres meses. Los instrumentos que se utilizaron fueron: el "Listado de síntomas revisado" (SCL-90-R), la "Escala de riesgo suicida" (RS) y el "Cuestionario de salud SF-36" (SF-36). Los resultados obtenidos muestran diferencias significativas entre las medidas previas al tratamiento y al finalizarlo en las principales dimensiones de las escalas aplicadas, manteniéndose estos resultados en el seguimiento a los tres meses. Los resultados sugieren que la terapia cognitivo conductual grupal, debido a su eficacia y eficiencia, podría ser utilizada como un primer nivel de atención al trastorno adaptativo


The goal at this research is to study the effectiveness of a cognitive behavioral group therapy program in patients with adjustment disorder. The sample is made up of 102 patients from two Mental Health units and a Primary Care Center in Valencia (Spain). The treatment was a cognitive behavioral group intervention of one hour and a half session per week during eight weeks. Patients were evaluated at the beginning and end of the program. Monitoring was performed at three months. The resources used were: the Symptom Checklist-90-Revised (SCL-90-R), the Suicide Risk Scale (RS) and the SF-36 Health Survey (SF-36). The results show significant differences between previous and following treatment measures on key dimensions of the applied scales, maintaining these results at 3 months follow-up. The results suggest that cognitive-behavioral group therapy could be used as a first level of attention to adjustment disorder because of its effectiveness and efficiency


Assuntos
Humanos , Psicoterapia de Grupo/métodos , Terapia Cognitivo-Comportamental/métodos , Transtornos de Adaptação/terapia , Ideação Suicida , Estudos Controlados Antes e Depois/métodos , Psicometria/instrumentação
5.
Sensors (Basel) ; 16(6)2016 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-27240365

RESUMO

There is, at present, considerable interest in the storage and dispatchability of photovoltaic (PV) energy, together with the need to manage power flows in real-time. This paper presents a new system, PV-on time, which has been developed to supervise the operating mode of a Grid-Connected Utility-Scale PV Power Plant in order to ensure the reliability and continuity of its supply. This system presents an architecture of acquisition devices, including wireless sensors distributed around the plant, which measure the required information. It is also equipped with a high-precision protocol for synchronizing all data acquisition equipment, something that is necessary for correctly establishing relationships among events in the plant. Moreover, a system for monitoring and supervising all of the distributed devices, as well as for the real-time treatment of all the registered information, is presented. Performances were analyzed in a 400 kW transformation center belonging to a 6.1 MW Utility-Scale PV Power Plant. In addition to monitoring the performance of all of the PV plant's components and detecting any failures or deviations in production, this system enables users to control the power quality of the signal injected and the influence of the installation on the distribution grid.

8.
Artigo em Inglês | MEDLINE | ID: mdl-19351566

RESUMO

Porphyrins are a widespread group of pigments in nature, but, contrary to melanins and carotenoids, their occurrence as plumage colorants seems to be anecdotal and their function, if any, is unknown. Using thin-layer chromatography and high pressure liquid chromatography, we have found coproporphyrin III, the same porphyrin type previously reported in owls, in the plumage of nestling black-shouldered kites (Elanus caeruleus). The first plumage grown at the nest in this species includes reddish-brown contour feathers in the upperparts, and particularly in the breast area, which fade during the weeks-long post-fledging period to become either gray or white consistent with the definitive adult plumage. In these reddish feathers, we have also found small amounts of pheomelanins and traces of eumelanin. The contribution of each pigment to the final colour perceived by birds or other animals is unknown. In white and grey feathers of the same species no porphyrin was found, and only traces of eumelanin were detected in the grey ones. The fact that the reddish feathers are only found in the juvenal plumage, when individuals are vulnerable in an open nest, leads us to hypothesize a camouflage role for this ephemeral plumage. As porphyrins are involved, although not exclusively, we can for the first time ascribe them a function in the plumage of birds.


Assuntos
Falconiformes/fisiologia , Plumas/fisiologia , Melaninas/fisiologia , Pigmentação/fisiologia , Porfirinas/fisiologia , Animais , Cromatografia Líquida de Alta Pressão , Cromatografia em Camada Fina
9.
Ecology ; 89(9): 2369-76, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18831156

RESUMO

The ecology of nectarivorous microbial communities remains virtually unknown, which precludes elucidating whether these organisms play some role in plant-pollinator mutualisms beyond minor commensalism. We simultaneously assessed microbial abundance and nectar composition at the individual nectary level in flowers of three southern Spanish bumble bee-pollinated plants (Helleborus foetidus, Aquilegia vulgaris, and Aquilegia pyrenaica cazorlensis). Yeasts were frequent and abundant in nectar of all species, and variation in yeast density was correlated with drastic changes in nectar sugar concentration and composition. Yeast communities built up in nectar from early to late floral stages, at which time all nectaries contained yeasts, often at densities between 10(4) and 10(5) cells/mm3. Total sugar concentration and percentage sucrose declined, and percentage fructose increased, with increasing density of yeast cells in nectar. Among-nectary variation in microbial density accounted for 65% (H. foetidus and A. vulgaris) and 35% (A. p. cazorlensis) of intraspecific variance in nectar sugar composition, and 60% (H. foetidus) and 38% (A. vulgaris) of variance in nectar concentration. Our results provide compelling evidence that nectar microbial communities can have detrimental effects on plants and/or pollinators via extensive nectar degradation and also call for a more careful interpretation of nectar traits in the future, if uncontrolled for yeasts.


Assuntos
Aquilegia/microbiologia , Abelhas/fisiologia , Flores/microbiologia , Helleborus/microbiologia , Polinização/fisiologia , Animais
10.
Am J Bot ; 95(3): 315-20, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21632356

RESUMO

We experimentally tested the hypothesis that the extensive within-plant variation of nectar sugar composition in Helleborus foetidus (Ranunculaceae) and other species results from differences between flowers and nectaries in pollinator visitation history. Experiments were conducted to mimic single-nectary visits by wild-caught individuals of the main bee pollinators of H. foetidus, which were assayed for their capacity to modify the sugar composition of natural and artificial nectar. Experimental nectar probing with bee mouthparts induced extensive changes in proportional sugar composition 48 h after treatment, and bee taxa differed widely in their effects. Nectar probing by Andrena, medium-sized Anthophoridae, Apis mellifera, and Lasioglossum had no subsequent effects on nectar sugar composition, while probing by Bombus terrestris and B. pratorum induced an extensive reduction in percentage sucrose, a marked increase in percentage fructose, and a slight increase in percentage glucose. Results support the hypothesis that stochastic variations among flowers or nectaries in the taxonomic identity of recent visitors and their relative visitation frequencies may eventually generate very small-scale mosaics in nectar sugar composition. Changes in nectar sugar composition following bumblebee probing may be the consequence of nectar contamination with pollinator-borne nectarivorous yeasts.

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