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INTRODUCTION: A meningeal solitary fibrous tumor (SFT), also called hemangiopericytoma, is a rare mesenchymal malignancy. Due to anatomic constrains, even after macroscopic complete surgery with curative intent, the local relapse risk is still relatively high, thus increasing the risk of dedifferentiation and metastatic spread. This study aims to better define the role of postoperative radiotherapy (RT) in meningeal SFTs. PATIENTS AND METHODS: A retrospective study was performed across seven sarcoma centers. Clinical information was retrieved from all adult patients with meningeal primary localized SFT treated between 1990 and 2018 with surgery alone (S) compared to those that also received postoperative RT (S + RT). Differences in treatment characteristics between subgroups were tested using independent samples t-test for continuous variables and chi-square tests for proportions. Local control (LC) and overall survival (OS) rates were calculated as time from start of treatment until progression or death from any cause. LC and OS in groups receiving S or S + RT were compared using Kaplan-Meier survival curves. RESULTS: Among a total of 48 patients, 7 (15%) underwent S and 41 (85%) underwent S + RT. Median FU was 65 months. LC was significantly associated with treatment. LC after S at 60 months was 60% versus 90% after S + RT (p = 0.052). Furthermore, R1 resection status was significantly associated with worse LC (HR 4.08, p = 0.038). OS was predominantly associated with the mitotic count (HR 3.10, p = 0.011). CONCLUSION: This retrospective study, investigating postoperative RT in primary localized meningeal SFT patients, suggests that combining RT to surgery in the management of this patient population may reduce the risk for local failures.
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Hemangiopericitoma , Neoplasias Meníngeas , Tumores Fibrosos Solitarios , Adulto , Hemangiopericitoma/radioterapia , Hemangiopericitoma/cirugía , Humanos , Neoplasias Meníngeas/radioterapia , Neoplasias Meníngeas/cirugía , Recurrencia Local de Neoplasia , Estudios Retrospectivos , Tumores Fibrosos Solitarios/radioterapia , Tumores Fibrosos Solitarios/cirugíaRESUMEN
AIMS: The survival benefit of radiation therapy in gastric cancer patients who underwent curative resection remains contentious. MATERIALS AND METHODS: Gastric cancer patients who underwent curative resection followed by adjuvant chemotherapy or chemoradiation therapy (CRT) between 2004 and 2014 were identified from the National Cancer Database. Survival analyses were carried out with the Kaplan-Meier method and the Cox regression model. RESULTS: In total, 4347 patients were included in this study. Of these patients, 1185 patients received postoperative chemotherapy alone and 3162 patients received postoperative CRT. For all patients included in the analysis, patients who received CRT had significantly better overall survival than those who received chemotherapy alone (5-year overall survival: 54.8% versus 46.8%, P < 0.001). The survival benefit primarily occurred in patients with stage II (5-year overall survival: 58.7% versus 53.8%, P = 0.03), stage III (42.5% versus 30.3%, P < 0.001) and lymph node-positive (5-year overall survival: 52.2% versus 41.9%, P = 0.03) gastric cancer. Multivariable analysis confirmed the improvement in overall survival in patients who received postoperative CRT (hazard ratio = 0.78; 95% confidence interval, 0.661-0.926; P < 0.001) was independent of all known prognostic factors. For lymph node-positive patients with lymphovascular invasion (LVI), postoperative CRT significantly improved overall survival compared with chemotherapy alone (5-year overall survival: 49.0% versus 39.4%, P = 0.001). However, there was no survival difference between CRT and chemotherapy alone if lymph node-positive patients had no LVI (5-year overall survival: 54.5% versus 52.7%, P = 0.55). CONCLUSION: The current study suggests that postoperative CRT provides a survival benefit in gastric cancer patients with concurrent lymph node-positive and LVI-positive disease. A randomised clinical trial may further evaluate the benefit of adjuvant CRT in this subgroup.
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Quimioradioterapia Adyuvante/métodos , Terapia Combinada/métodos , Neoplasias Gástricas , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Neoplasias Gástricas/tratamiento farmacológico , Neoplasias Gástricas/mortalidad , Neoplasias Gástricas/radioterapia , Neoplasias Gástricas/cirugía , Análisis de SupervivenciaRESUMEN
BACKGROUND: Although cytoreductive surgery has been shown to be beneficial in carefully selected patients with metastatic gastrointestinal stromal tumours (GISTs) treated with tyrosine kinase inhibitors (TKIs), factors predictive of postoperative morbidity have not been investigated previously. METHODS: A surgical complexity score for GIST metastasectomy (GM-SCS) composed of patient-related and surgical factors was assigned retrospectively to patients with metastatic GIST treated with TKI therapy and surgery at two institutions between 2002 and 2014. The ability of clinicopathological factors and GM-SCS to predict postoperative morbidity was assessed by means of a multivariable logistic regression model. Postoperative complications were categorized using the Clavien-Dindo classification. RESULTS: Some 400 operations on 323 patients with metastatic GIST on TKIs were included. Complications were observed following 110 operations (27·5 per cent) including 70 major complications (grade III-V) (17·5 per cent of 400 operations). Patients were divided into low (5 points or less; 100 patients, 25·0 per cent), intermediate (6-9 points; 191, 47·8 per cent) and high (at least 10 points; 109, 27·3 per cent) complexity scoring groups based on the GM-SCS. An intermediate (odds ratio (OR) 2·88; P = 0·008) and high (OR 5·40; P < 0·001) GM-SCS were independent predictors of overall complications, whereas only a high GM-SCS was independently predictive of a major complication (OR 3·65; P = 0·018). Metastatic mitotic index was also an independent predictor of overall complications (OR 2·55; P = 0·047). GM-SCS did not predict progression-free or overall survival. CONCLUSION: A gastrointestinal stromal tumour metastastectomy surgical complexity score can predict morbidity, which may help in preoperative risk stratification and optimal treatment planning.
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Antineoplásicos/uso terapéutico , Procedimientos Quirúrgicos de Citorreducción , Neoplasias Gastrointestinales/cirugía , Tumores del Estroma Gastrointestinal/cirugía , Mesilato de Imatinib/uso terapéutico , Proteínas Tirosina Quinasas/antagonistas & inhibidores , Anciano , Terapia Combinada/efectos adversos , Terapia Combinada/métodos , Procedimientos Quirúrgicos de Citorreducción/efectos adversos , Neoplasias Gastrointestinales/patología , Neoplasias Gastrointestinales/terapia , Tumores del Estroma Gastrointestinal/patología , Tumores del Estroma Gastrointestinal/terapia , Humanos , Metastasectomía , Persona de Mediana Edad , Factores de RiesgoRESUMEN
In August 2010, a mycelial fan (isolate AZ32F) of Armillaria sp. was collected from the root collar of a living Douglas-fir tree on the Mogollon Rim within the Coconino National Forest (approximate location 34°25'31.26â³N, 111°20'41.04â³W, elevation 2,293 m) in central Arizona. Mycelial fans under the bark of living trees are a sign of pathogenicity, and symptoms of the diseased tree included resinosis, sloughing bark, and thinning crown. The infected tree was located on a south-facing slope with approximately 30% tree cover, dominated by ponderosa pine (Pinus ponderosa), with lesser components of Douglas-fir and Gambel oak (Quercus gambelii). Based on three replications of somatic incompatibility tests against 24 tester isolates representing seven North American Armillaria spp., isolate AZ32F showed 100% intraspecific compatibility (colorless antagonism) with all four A. gallica isolates, 22% compatibility with A. calvescens, and 0% compatibility with the remaining Armillaria spp. Based on GenBank BLASTn of isolate AZ32F sequences, the partial LSU-IGS1 (GenBank Accession No. KF186682) showed 99 to 100% similarity to A. gallica and two other related Armillaria spp. with 99 to 100% coverage, and translation elongation factor-1 alpha (tef-1α) sequences (KC525954) showed 96% similarity to A. gallica (JF895844) with 100% coverage. Thus, isolate AZ32F was identified as A. gallica, based on somatic incompatibility tests and DNA sequences (partial LSU-IGS1 and tef-1α). Although the isolate is identified as A. gallica with similarities to other North American isolates, evidence is mounting that currently recognized A. gallica likely represents a species complex that comprises multiple phylogenetic species (4). Previous surveys in Arizona have noted A. mellea and A. solidipes (as A. ostoyae) (3), but A. gallica has never been previously confirmed in this state. Within North America, A. gallica is commonly reported east of the Rocky Mountains and in West Coast states of the United States, where it infects hardwoods and conifers including Douglas-fir (1,2). Its ecological behavior ranges from saprophyte to weak/aggressive pathogen (1,2). Because damage by A. gallica appears to increase on hosts predisposed by stress (1), further surveys are needed to document its distribution, frequency, and ecological behavior in the southwestern United States, where climate change will likely cause tree stress due to maladaptation. Continued surveys for Armillaria spp. will better determine their potential threat within the geologically and ecologically unique Mogollon Rim of Arizona. References: (1) K. Baumgartner and D. M. Rizzo. Plant Dis. 85:947, 2001. (2) N. J. Brazee and R. L. Wick. For. Ecol. Manage. 258:1605, 2009. (3) R. L. Gilbertson and D. M. Bigelow. J. Arizona-Nevada Acad. Sci. 31:13, 1998. (4) M.-S. Kim et al. Phytopathology 102:S4.63, 2012.
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White pine blister rust, caused by Cronartium ribicola J.C. Fisch., was found on southwestern white pine (Pinus flexilis James var. reflexa Engelm., synonym P. strobiformis Engelm.) near Hawley Lake, Arizona (Apache County, White Mountains, 34.024°N, 109.776°W, elevation 2,357 m) in April 2009. Although white pines in the Southwest (Arizona and New Mexico) have been repeatedly surveyed for blister rust since its discovery in the Sacramento Mountains of southern New Mexico in 1990 (1,2), this was the first confirmation of C. ribicola in Arizona. Numerous blister rust cankers were sporulating on 15- to 30-year-old white pines growing in a mixed conifer stand adjacent to a meadow with orange gooseberry bushes (Ribes pinetorum Greene), a common telial host in New Mexico. Most of the observed cankers were producing their first aecia on 5-year-old branch interwhorl segments (i.e., formed in 2004). The two oldest cankers apparently originated on stemwood formed about 14 and 21 years before (1995 and 1988). Neither uredinia nor telia were seen on expanding gooseberry leaves in late April, but these rust structures were found later in the season. Voucher specimens deposited in the Forest Pathology Herbarium-Fort Collins (FPF) were determined by host taxa and macro- and microscopic morphology as C. ribicola-white pine with typical cankers, aecia, and aeciospores (1). Six collections of aeciospores from single, unopened aecia provided rDNA sequences (ITS1-5.8S-ITS2, primers ITS1F and ITS4) with two different repeat types (GenBank Accession Nos. HM156043 and HM156044 [J. W. Hanna conducted analysis with methods described in 3]). A BLASTn search with these sequences showed 100 and 99% similarities, respectively, with sequences of C. ribicola, including accessions L76496, L76498, and L76499 from California (4). Additional reconnaissance of white pines on the Fort Apache Indian Reservation and neighboring Apache-Sitgreaves National Forests was conducted from May through September 2009. Although the blister rust infestation was distributed over more than 100 km2 of forest type, infected trees were restricted to mesic and wet canyon bottoms (climatically high-hazard sites) and were not found on dry sites-even where aecial and telial hosts occurred together. Recent dispersal within the White Mountains was suggested by a presence of infected gooseberry plants on several sites where infected white pines were not yet evident. Geils et al. (1) concluded that the initial infestation in New Mexico had originated by long-distance, aerial transport from California to the Sacramento Mountains in 1969. Since then, numerous additional infestations in the Southwest have been discovered; but we do not know which of these (including Arizona) resulted by dispersal from California or New Mexico. Although rust may eventually infest many host populations in the Southwest and disease may kill most trees in some locations, differences in site hazard and spread provide managers with numerous opportunities to maintain white pines and Ribes spp. References: (1) B. Geils et al. For. Pathol. 40:147, 2010. (2) F. Hawksworth. Plant Dis. 74:938, 1990. (3) M.-S. Kim et al. For. Pathol. 36:145, 2006. (4) D. Vogler and T. Bruns. Mycologia 90:244, 1998.
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Size segregation is a natural occurrence both in everyday life and in industrial processes. Understanding and research of the phenomenon has overwhelmingly been from a mechanistic point of view. This paper demonstrates through simulations that segregation can also be explained and trends predicted geometrically. The algorithm used in this study contains three simple elements: random walks combined with a rebounding probability to encourage particles to settle, plus the non-overlap constraint. It is implemented digitally in a regular lattice grid, to make it easy to deal with arbitrary shapes. It does not explicitly consider any particle interaction forces, and it does not include any rules specifically designed to promote or suppress segregation. Yet particle movement, which occurs within a digitized cubic grid, leads to shaking-induced segregation comparable to that observed in physical tests. The paper details the comparison of shaking-induced particle segregation between a series of computer based simulations and those of physical experiments undertaken in the laboratory. A range of mixtures, comprising nonspherical, arbitrary shaped/sized particles are investigated, having been packed into pseudo-two-dimensional containers. The simulation results suggest that segregation can be adequately explained, from a geometrical point of view, as a result of the relative motion between particles of different sizes and shapes. The geometrical algorithm thus provides a fast and qualitative prediction as to how likely segregation is to occur for any given mixture of arbitrary shapes.
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Bowlers in cricket try to disguise their bowling action by movement pattern similarity. The batter's task is, therefore, to solve rapidly perceptual discrimination problems. Previous research has suggested that batters can discriminate perceptual cues that provide depth or target information. However, at present, there is a lack of applied research evidence on further perceptual cue utilization, including bowling delivery identification. This ability is required when batting against wrist-spin bowlers who may use five different types of delivery. In the present study, we assessed this perceptual discrimination ability among three distinct standards of batters. In addition, the relative potency of body action and ball flight information was assessed by visual occlusion techniques. We found that more expert batters in general showed greater perceptual discrimination skills when faced with different ball types. However, this discrimination ability was linked specifically to delivery type and to previous experience. We also found that additional ball flight information provided no more advantage to this discrimination ability. This finding reinforces the importance of advanced cue information and the need to expose cricket batters to different bowling actions. Further study of the development of movement pattern recognition is recommended.
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Aprendizaje Discriminativo/fisiología , Desempeño Psicomotor/fisiología , Deportes/fisiología , Adulto , Fenómenos Biomecánicos , Humanos , Masculino , Muñeca/fisiologíaRESUMEN
Photosystem II from higher plant chloroplasts contains extrinsic proteins of molecular weights 33, 23 and 16 kDa. Cyanobacteria, which are thought to be closely related to the evolutionary progenitor of chloroplasts, have a protein homologous to the largest of these, but lack homologues of the smaller ones. Here we report immunological evidence for the occurrence of the 33 kDa extrinsic protein in red and chromophyte algae and its absence from anoxygenic photosynthetic bacteria. The 23 kDa protein was absent from all three groups. The red algal protein was found to be hydrophilic and rather more loosely associated with the thylakoid membrane than its higher plant equivalent. These findings support an origin for all plastids among the oxygenic prokaryotes, in contrast to the phylogeny inferred from ribulose bisphosphate carboxylase-oxygenase sequence data.
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Eucariontes/metabolismo , Proteínas del Complejo del Centro de Reacción Fotosintética/metabolismo , Evolución Biológica , Cianobacterias/metabolismo , Eucariontes/clasificación , Peso Molecular , Phaeophyceae/metabolismo , Proteínas del Complejo del Centro de Reacción Fotosintética/química , Complejo de Proteína del Fotosistema II , Plastidios/metabolismo , Rhodophyta/metabolismo , SimbiosisRESUMEN
An extreme preference in processing information within either the left or right hemisphere is known as hemisphericity. A previous study investigating hemisphericity as a factor in motor skill learning (Murray, 1979) found that matching subjects' hemisphericity characteristics with hemispherical teaching strategies enhanced skill acquisition. In contrast, our study examined the effects of hemispherical teaching strategies on a group of subjects who did not present hemisphericity. Right-handed male high school students were randomly assigned to either a left hemisphere, right hemisphere, or an interhemispherical teaching condition. Subjects in the right hemisphere and interhemispherical conditions performed and learned the skill more effectively than subjects in the left hemisphere teaching condition. The right hemisphere and interhemispherical groups performed comparably in acquisition; however, the interhemispherical group showed significantly better retention of the skill. Motor skill acquisition and retention for nondominant processors appears best served by directing both verbal and nonverbal attention to the skill.
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Dominancia Cerebral , Aprendizaje , Destreza Motora , Adolescente , Humanos , Masculino , Aprendizaje VerbalRESUMEN
In two experiments we examined the effectiveness of ideokinetic imagery and flexibility combined with abdominal strength training as methods for improving the spinal angles of lordosis and kyphosis and reducing low back pain. Ideokinetic imagery is a postural development technique that involves using movement images to gain subcortical control over the spinal musculature. Experiment 1 investigated the effectiveness of these treatments for males with a previous history of low back pain. Findings indicated that only ideokinetic imagery had a positive effect on the spinal column and low back pain. Experiment 2 extended these findings by investigating males and females using a noninvasive video analysis technique to record changes in spinal angles. This study further supports the effectiveness of ideokinetic imagery as a postural development technique in males with acute spinal angles. In these subjects spinal angles improved significantly, and the subjects reported complete cessation of low back pain. This research supports the use of ideokinetic imagery as an inexpensive and noninvasive technique to improve poor posture and reduce low back pain.