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1.
Mol Ecol ; 31(5): 1430-1443, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34908199

RESUMO

Freshwater habitats are under stress from agricultural land use, most notably the influx of neonicotinoid pesticides and increased nutrient pressure from fertilizer. Traditional studies investigating the effects of stressors on freshwater systems are often limited to a narrow range of taxa, depending heavily on morphological expertise. Additionally, disentanglement of multiple simultaneous stressors can be difficult in field studies, whereas controlled laboratory conditions do not accurately reflect natural conditions and food webs. To overcome these drawbacks, we investigated the impacts of two agricultural stressors (the neonicotinoid insecticide thiacloprid and fertilizer) in full-factorial design in a semi-natural research site, using environmental DNA sampling to study three different taxonomic groups representing three trophic levels: bacteria (decomposers), phytoplankton (primary producers), and chironomids (consumers). The results show considerable impact of both stressors across trophic levels, with an additive effect of fertilizer and thiacloprid on community composition at all levels. These findings suggest that agricultural stressors affect the entire food web, either directly or through cascade reactions. They are also consistent with morphological assessments that were performed in the same study site, even at a lower number of replicates. The study presented shows that the use of multimarker environmental DNA provides a more comprehensive assessment of stressor impacts across multiple trophic levels, at a higher taxonomic resolution than traditional surveys. Additionally, many putative novel bioindicators for both agricultural stressors were discovered. We encourage further investigations into stressors impacts at different trophic levels, which will lead to more effective monitoring and management of freshwater systems.


Assuntos
DNA Ambiental , Código de Barras de DNA Taxonômico , Ecossistema , Água Doce , Rios
2.
BMC Med ; 18(1): 114, 2020 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-32460859

RESUMO

BACKGROUND: The five-tiered Cambridge Prognostic Group (CPG) classification is a better predictor of prostate cancer-specific mortality than the traditional three-tiered classification (low, intermediate, and high risk). We investigated radical treatment rates according to CPG in men diagnosed with non-metastatic prostate cancer in England between 2014 and 2017. METHODS: Patients diagnosed with non-metastatic prostate cancer were identified from the National Prostate Cancer Audit database. Men were risk stratified according to the CPG classification. Risk ratios (RR) were estimated for undergoing radical treatment according to CPG and for receiving radiotherapy for those treated radically. Funnel plots were used to display variation in radical treatment rates across hospitals. RESULTS: A total of 61,999 men were included with 10,963 (17.7%) in CPG1 (lowest risk group), 13,588 (21.9%) in CPG2, 9452 (15.2%) in CPG3, 12,831 (20.7%) in CPG4, and 15,165 (24.5%) in CPG5 (highest risk group). The proportion of men receiving radical treatment increased from 11.3% in CPG1 to 78.8% in CGP4, and 73.3% in CPG5. Men in CPG3 were more likely to receive radical treatment than men in CPG2 (66.3% versus 48.4%; adjusted RR 1.44; 95% CI 1.36-1.53; P < 0.001). Radically treated men in CPG3 were also more likely to receive radiotherapy than men in CPG2 (59.2% versus 43.9%; adjusted RR, 1.18; 95% CI 1.10-1.26). Although radical treatment rates were similar in CPG4 and CPG5 (78.8% versus 73.3%; adjusted RR 1.01; 95% CI 0.98-1.04), more men in CPG5 had radiotherapy than men in CPG4 (79.9% versus 59.1%, adjusted RR 1.26; 95% CI 1.12-1.40). CONCLUSIONS: The CPG classification distributes men in five risk groups that are about equal in size. It reveals differences in treatment practices in men with intermediate-risk disease (CPG2 and CPG3) and in men with high-risk disease (CPG4 and CPGP5) that are not visible when using the traditional three-tiered risk classification.


Assuntos
Neoplasias da Próstata/terapia , Idoso , Idoso de 80 Anos ou mais , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Fatores de Risco
3.
Chem Sci ; 13(6): 1789-1800, 2022 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-35282626

RESUMO

We investigate interatomic Coulombic decay in NeKr dimers after neon inner-valence photoionization [Ne+(2s-1)] using a synchrotron light source. We measure with high energy resolution the two singly charged ions of the Coulomb-exploding dimer dication and the photoelectron in coincidence. By carefully tracing the post-collision interaction between the photoelectron and the emitted ICD electron we are able to probe the temporal evolution of the state as it decays. Although the ionizing light pulses are 80 picoseconds long, we determine the lifetime of the intermediate dimer cation state and visualize the contraction of the nuclear structure on the femtosecond time scale.

4.
J La State Med Soc ; 163(5): 254-5, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22272546

RESUMO

Aneurysms of the sinus of Valsalva are uncommon. These aneurysms often present as a rupture from the right coronary sinus into the right ventricle or right atrium. Rupture into the pulmonary artery is rare, with only six other reported cases. We present here a case of rupture from the right coronary sinus into the pulmonary artery, along with a brief review of the related current literature and recommendations.


Assuntos
Aneurisma da Aorta Torácica/diagnóstico , Aneurisma da Aorta Torácica/cirurgia , Ruptura Aórtica/diagnóstico , Ruptura Aórtica/cirurgia , Seio Aórtico/cirurgia , Adulto , Meios de Contraste , Angiografia Coronária , Diagnóstico Diferencial , Ecocardiografia Transesofagiana , Feminino , Humanos
5.
Sci Rep ; 11(1): 2772, 2021 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-33531568

RESUMO

Biological invasions by nonindigenous species can have negative effects on economies and ecosystems. To limit this impact, current research on biological invasions uses functional traits to facilitate a mechanistic understanding of theoretical and applied questions. Here we aimed to assess the role of functional traits in the progression of crayfish species through different stages of invasion and determine the traits associated with invasive success. A dataset of thirteen functional traits of 15 species currently occurring or available for sale in the Netherlands was evaluated. Six of these crayfish appeared invasive. Important traits distinguishing successful from unsuccessful invaders were a temperate climate in the native range, a medium to high egg count and producing more than one egg clutch per year. The most successful invaders had different functional trait combinations: Procambarus clarkii has a higher reproductive output, can migrate over longer distances and possesses a higher aggression level; Faxonius limosus is adapted to a colder climate, can reproduce parthenogetically and has broader environmental tolerances. Using a suit of functional traits to analyse invasive potential can help risk management and prevention. For example, based on our data Procambarus virginalis is predicted to become the next successful invasive crayfish in the Netherlands.


Assuntos
Astacoidea/fisiologia , Espécies Introduzidas , Alimentos Marinhos , Animais , Países Baixos
6.
IEEE Trans Biomed Eng ; 68(12): 3701-3712, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34014821

RESUMO

OBJECTIVE: Our goal was to analyze the electrophysiological response to direct electrical stimulation (DES) systematically applied at a wide range of parameters and anatomical sites, with particular focus on neural activities associated with memory and cognition. METHODS: We used a large set of intracranial EEG (iEEG) recordings with DES from 45 subjects with electrodes implanted both subdurally on the cortical surface and subcortically into the brain parenchyma. Subjects were stimulated in blocks of alternating frequency and amplitude parameters during quiet wakefulness. RESULTS: Stimulating at different frequencies and amplitudes of electric current revealed a persistent pattern of response in the slow and the fast neural activities. In particular, amplification of the theta (4-7 Hz) and attenuation of the gamma (29-52 Hz) power-in-band was observed with increasing the stimulation parameters. This opposite effect on the low and high frequency bands was found across a network of selected local and distal sites proportionally to the proximity and magnitude of the electric current. Power increase in the theta and decrease in the gamma band was driven by the total electric charge delivered with either increasing the frequency or amplitude of the stimulation current. This inverse effect on the theta and gamma activities was consistently observed in response to different stimulation frequencies and amplitudes. CONCLUSION: Our results suggest a uniform DES effect of amplifying theta and suppressing gamma neural activities in the human brain. SIGNIFICANCE: These findings reveal the utility of simple power-in-band features for understanding and optimizing the effects of electrical stimulation on brain functions.


Assuntos
Encéfalo , Eletroencefalografia , Cognição , Estimulação Elétrica , Cabeça , Humanos , Ritmo Teta
8.
Clin Oncol (R Coll Radiol) ; 32(8): 501-508, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32143901

RESUMO

AIMS: Randomised controlled trials have shown comparable early oncological outcomes after hypofractionated and conventionally fractionated radiotherapy in the radical treatment of prostate cancer (PCa). The effect of hypofractionation on treatment-related gastrointestinal and genitourinary toxicity remains uncertain, especially in older men and those with locally advanced PCa. MATERIALS AND METHODS: A population-based study of all patients treated with radical conventionally fractionated radiotherapy (n = 9106) and hypofractionated radiotherapy (n = 3027) in all radiotherapy centres in the English National Health Service between 2014 and 2016 was carried out. We identified severe gastrointestinal and genitourinary toxicity using a validated coding framework and compared conventionally fractionated and hypofractionated radiotherapy using a competing-risks proportional hazards regression analysis. RESULTS: The median age in our cohort was 72 years old and most patients had locally advanced disease (65%). There was no difference in gastrointestinal toxicity (conventionally fractionated radiotherapy: 5.0 events/100 person-years; hypofractionated radiotherapy: 5.2 events/100 person-years; adjusted subdistribution hazard ratio: 1.00, 95% confidence interval: 0.89-1.13; P = 0.95) or genitourinary toxicity (conventionally fractionated radiotherapy: 2.3 events/100 person-years; hypofractionated radiotherapy: 2.3 events/100 person-years; adjusted subdistribution hazard ratio: 0.92, 95% confidence interval: 0.77-1.10; P = 0.35) between patients who received conventionally fractionated radiotherapy and those who received hypofractionated radiotherapy. CONCLUSIONS: This national cohort study has shown that the use of hypofractionated radiotherapy in the radical treatment of PCa does not increase rates of severe gastrointestinal or genitourinary toxicity. Our findings also support the use of hypofractionated radiotherapy in older men and those with locally advanced PCa.


Assuntos
Gastroenteropatias/patologia , Neoplasias da Próstata/radioterapia , Radioterapia/efeitos adversos , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Gastroenteropatias/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias da Próstata/epidemiologia , Neoplasias da Próstata/patologia , Hipofracionamento da Dose de Radiação , Ensaios Clínicos Controlados Aleatórios como Assunto , Medicina Estatal , Resultado do Tratamento , Reino Unido/epidemiologia
9.
Indian J Lepr ; 81(1): 5-11, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-20329362

RESUMO

To assess the level of awareness about the different provisions of the persons with Disability Act (1995) among the health care professionals, 201 health care professionals dealing with the disabled persons from different parts of India were interviewed using structured interview checklist. The data were analysed through statistical package of social sciences software. Chi-square test were applied on the variables and the Pvalues were ascertained. The results show that 48.3% knew about administration hierarchy, 53.7% of respondents were aware of the free education available for the disabled, 68.5% were aware of the employment scheme, 62.7% about poverty alleviation schemes, 59.2% know about the traveling benefits, 56.2% of professionals were aware of the benefits for people with low vision. Only 29.9% of respondents knew about provisions to overcome architectural barriers. 43.8% of them knew about the least disability percentage whereas only 28.4% were aware of research and manpower schemes. Regarding affirmative action, 32.17% told correctly and 52.7% of the professionals responded correctly with respectto non- discrimination schemes. The level of awareness among the professionals working in rural regions is lower with regard to administration hierarchy and poverty alleviation schemes. Informations regarding disabled friendly environments and research and manpower development were found to be low among respondents of all professions which need to be effectively intervened. Gender did not show any influence with respect to the components of the act. The study showed that there is an ample need for educational interventions among the health care professionals in all socio-demography. Inclusion of PWD Act in the curriculum of medical schools as a topic in conferences and workshops for health care professionals are suggested.


Assuntos
Pessoas com Deficiência/legislação & jurisprudência , Pessoal de Saúde/educação , Política de Saúde/legislação & jurisprudência , Adulto , Pessoas com Deficiência/educação , Feminino , Humanos , Índia , Masculino , Pessoa de Meia-Idade , População Rural , População Urbana
10.
PeerJ ; 7: e7335, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31388472

RESUMO

BACKGROUND: The heterogeneous nature of environmental DNA (eDNA) and its effects on species detection and community composition estimates has been highlighted in several studies in the past decades. Mostly in the context of spatial distribution over large areas, in fewer occasions looking at spatial distribution within a single body of water. Temporal variation of eDNA, similarly, has mostly been studied as seasonality, observing changes over large periods of time, and often only for small groups of organisms such as fish and amphibians. METHODS: We analyzed and compared small-scale spatial and temporal variation by sampling eDNA from two small, isolated dune lakes for 20 consecutive weeks. Metabarcoding was performed on the samples using generic COI primers. Molecular operational taxonomic unit (MOTUs) were used to assess dissimilarities between spatial and temporal replicates. RESULTS: Our results show large differences between samples taken within one lake at one point in time, but also expose the large differences between temporal replicates, even those taken only 1 week apart. Furthermore, between-site dissimilarities showed a linear correlation with time frame, indicating that between-site differences will be inflated when samples are taken over a period of time. We also assessed the effects of PCR replicates and processing strategies on general patterns of dissimilarity between samples. While more inclusive PCR replicate strategies lead to higher richness estimations, dissimilarity patterns between samples did not significantly change. CONCLUSIONS: We conclude that the dissimilarity of temporal replicates at a 1 week interval is comparable to that of spatial replicate samples. It increases, however, for larger time intervals, which suggests that population turnover effects can be stronger than community heterogeneity. Spatial replicates alone may not be enough for optimal recovery of taxonomic diversity, and cross-comparisons of different locations are susceptible to inflated dissimilarities when performed over larger time intervals. Many of the observed MOTUs could be classified as either phyto- or zooplankton, two groups that have gained traction in recent years as potential novel bio-indicator species. Our results, however, indicate that these groups might be susceptible to large community shifts in relatively short periods of time, highlighting the need to take temporal variations into consideration when assessing their usability as water quality indicators.

11.
PLoS One ; 14(12): e0226527, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31841568

RESUMO

DNA-based identification through the use of metabarcoding has been proposed as the next step in the monitoring of biological communities, such as those assessed under the Water Framework Directive (WFD). Advances have been made in the field of metabarcoding, but challenges remain when using complex samples. Uneven biomass distributions, preferential amplification and reference database deficiencies can all lead to discrepancies between morphological and DNA-based taxa lists. The effects of different taxonomic groups on these issues remain understudied. By metabarcoding WFD monitoring samples, we analyzed six different taxonomic groups of freshwater organisms, both separately and combined. Identifications based on metabarcoding data were compared directly to morphological assessments performed under the WFD. The diversity of taxa for both morphological and DNA-based assessments was similar, although large differences were observed in some samples. The overlap between the two taxon lists was 56.8% on average across all taxa, and was highest for Crustacea, Heteroptera, and Coleoptera, and lowest for Annelida and Mollusca. Taxonomic sorting in six basic groups before DNA extraction and amplification improved taxon recovery by 46.5%. The impact on ecological quality ratio (EQR) scoring was considerable when replacing morphology with DNA-based identifications, but there was a high correlation when only replacing a single taxonomic group with molecular data. Different taxonomic groups provide their own challenges and benefits. Some groups might benefit from a more consistent and robust method of identification. Others present difficulties in molecular processing, due to uneven biomass distributions, large genetic diversity or shortcomings of the reference database. Sorting samples into basic taxonomic groups that require little taxonomic knowledge greatly improves the recovery of taxa with metabarcoding. Current standards for EQR monitoring may not be easily replaced completely with molecular strategies, but the effectiveness of molecular methods opens up the way for a paradigm shift in biomonitoring.


Assuntos
Organismos Aquáticos/classificação , Organismos Aquáticos/genética , Código de Barras de DNA Taxonômico/métodos , Monitorização de Parâmetros Ecológicos/métodos , Invertebrados/classificação , Invertebrados/genética , Animais , Anelídeos/classificação , Anelídeos/genética , Biodiversidade , Biota/genética , Crustáceos/classificação , Crustáceos/genética , DNA/análise , Bases de Dados Factuais , Água Doce/química , Moluscos/classificação , Moluscos/genética , Reprodutibilidade dos Testes , Qualidade da Água/normas
12.
Sci Total Environ ; 678: 499-524, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31077928

RESUMO

Effective identification of species using short DNA fragments (DNA barcoding and DNA metabarcoding) requires reliable sequence reference libraries of known taxa. Both taxonomically comprehensive coverage and content quality are important for sufficient accuracy. For aquatic ecosystems in Europe, reliable barcode reference libraries are particularly important if molecular identification tools are to be implemented in biomonitoring and reports in the context of the EU Water Framework Directive (WFD) and the Marine Strategy Framework Directive (MSFD). We analysed gaps in the two most important reference databases, Barcode of Life Data Systems (BOLD) and NCBI GenBank, with a focus on the taxa most frequently used in WFD and MSFD. Our analyses show that coverage varies strongly among taxonomic groups, and among geographic regions. In general, groups that were actively targeted in barcode projects (e.g. fish, true bugs, caddisflies and vascular plants) are well represented in the barcode libraries, while others have fewer records (e.g. marine molluscs, ascidians, and freshwater diatoms). We also found that species monitored in several countries often are represented by barcodes in reference libraries, while species monitored in a single country frequently lack sequence records. A large proportion of species (up to 50%) in several taxonomic groups are only represented by private data in BOLD. Our results have implications for the future strategy to fill existing gaps in barcode libraries, especially if DNA metabarcoding is to be used in the monitoring of European aquatic biota under the WFD and MSFD. For example, missing species relevant to monitoring in multiple countries should be prioritized for future collaborative programs. We also discuss why a strategy for quality control and quality assurance of barcode reference libraries is needed and recommend future steps to ensure full utilisation of metabarcoding in aquatic biomonitoring.


Assuntos
Organismos Aquáticos , Biota , Código de Barras de DNA Taxonômico , Monitoramento Ambiental , Biblioteca Gênica , Código de Barras de DNA Taxonômico/estatística & dados numéricos , Europa (Continente)
13.
J La State Med Soc ; 160(4): 204-7, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18828462

RESUMO

BACKGROUND DATA: On-pump and off-pump techniques are both widely used approaches to coronary artery bypass surgery. Yet, statistically valid comparisons of the results between the two groups have been limited, in part, by patient selection bias. METHODS: Two hundred sixty-nine consecutive patients undergoing off-pump coronary artery bypass and 379 consecutive patients undergoing on-pump bypass were compared in a retrospective chart review. The two groups were compared for preoperative characteristics as well as operative outcomes. To avoid selection bias, no on-pump coronary artery bypass surgery was performed during the off-pump coronary artery bypass series, and no patients were done off-pump during the coronary artery bypass series. RESULTS: There was no statistical difference in the groups pre-operatively except that there were slightly more patients with three-vessel disease in the on-pump group and more patients with single vessel disease in the off-pump group. Significant benefits were found in the off-pump group in that they required fewer re-operations for bleeding (0.8% vs. 5.7%, p-value < 0.002), and they left the hospital with higher hematocrits (32.1% vs. 30.8%, p-value < 0.001). Patients who had off-pump coronary artery bypass also had fewer sternal dehiscences (0% vs. 1.8%, p-value < 0.027). More patients receiving off-pump bypass demonstrated the need for prolonged mechanical ventilation (8.2% vs. 2.5%, p-value < 0.027), and they also had significantly fewer grafts (3 vs. 3.2, p-value < 0.005). There was no statistically significant difference among the other outcomes investigated. CONCLUSIONS: While there were no significant differences in some of the outcomes studied, others showed significant advantages in favor of off-pump surgery. Substantial advantages in off-pump coronary artery bypass were seen in bleeding reduction, improved sternal healing, and higher discharge hematocrits despite fewer transfusions. These advantages and others reported in specific high-risk patient groups, combined with documented cost reductions, warrant continued use of off-pump techniques. Off-pump coronary artery bypass is a safe, proven method with significant advantages over on-pump methods and, when appropriate, should be offered to patients undergoing coronary bypass surgery.


Assuntos
Ponte de Artéria Coronária sem Circulação Extracorpórea , Doença da Artéria Coronariana/cirurgia , Feminino , Hemorragia/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Estudos Retrospectivos , Fatores de Risco , Resultado do Tratamento
14.
J La State Med Soc ; 159(2): 101-3, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17539493

RESUMO

Embolus-in-transit leading to a paradoxical embolus or a pulmonary embolus is an uncommon phenomenon that requires a high degree of suspicion to make a clinical diagnosis. We present three interesting cases that have been encountered in our practice and describe the surgical treatment undertaken to correct the problem.


Assuntos
Embolia/diagnóstico , Complicações Pós-Operatórias , Embolia Pulmonar/diagnóstico , Trombose Venosa/diagnóstico , Idoso , Idoso de 80 Anos ou mais , Ponte de Artéria Coronária/efeitos adversos , Diagnóstico Diferencial , Ecocardiografia Doppler em Cores , Embolia/diagnóstico por imagem , Embolia/terapia , Fixação de Fratura/efeitos adversos , Derivação Gástrica/efeitos adversos , Comunicação Interatrial , Humanos , Masculino , Pessoa de Meia-Idade , Embolia Pulmonar/diagnóstico por imagem , Embolia Pulmonar/terapia , Tomografia Computadorizada Espiral , Resultado do Tratamento , Trombose Venosa/diagnóstico por imagem , Trombose Venosa/terapia
15.
Lancet ; 365(9475): 1942-9, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15936421

RESUMO

BACKGROUND: Exposure to environmental stressors can impair children's health and their cognitive development. The effects of air pollution, lead, and chemicals have been studied, but there has been less emphasis on the effects of noise. Our aim, therefore, was to assess the effect of exposure to aircraft and road traffic noise on cognitive performance and health in children. METHODS: We did a cross-national, cross-sectional study in which we assessed 2844 of 3207 children aged 9-10 years who were attending 89 schools of 77 approached in the Netherlands, 27 in Spain, and 30 in the UK located in local authority areas around three major airports. We selected children by extent of exposure to external aircraft and road traffic noise at school as predicted from noise contour maps, modelling, and on-site measurements, and matched schools within countries for socioeconomic status. We measured cognitive and health outcomes with standardised tests and questionnaires administered in the classroom. We also used a questionnaire to obtain information from parents about socioeconomic status, their education, and ethnic origin. FINDINGS: We identified linear exposure-effect associations between exposure to chronic aircraft noise and impairment of reading comprehension (p=0.0097) and recognition memory (p=0.0141), and a non-linear association with annoyance (p<0.0001) maintained after adjustment for mother's education, socioeconomic status, longstanding illness, and extent of classroom insulation against noise. Exposure to road traffic noise was linearly associated with increases in episodic memory (conceptual recall: p=0.0066; information recall: p=0.0489), but also with annoyance (p=0.0047). Neither aircraft noise nor traffic noise affected sustained attention, self-reported health, or overall mental health. INTERPRETATION: Our findings indicate that a chronic environmental stressor-aircraft noise-could impair cognitive development in children, specifically reading comprehension. Schools exposed to high levels of aircraft noise are not healthy educational environments.


Assuntos
Cognição , Nível de Saúde , Ruído dos Transportes/efeitos adversos , Aeronaves , Criança , Compreensão , Estudos Transversais , Feminino , Humanos , Masculino , Memória , Veículos Automotores , Países Baixos , Leitura , Instituições Acadêmicas , Espanha , Reino Unido
16.
IEEE Trans Biomed Eng ; 63(1): 67-75, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26151930

RESUMO

GOAL: Activities of neuronal networks range from action potential firing of individual neurons, coordinated oscillations of local neuronal assemblies, and distributed neural populations. Here, we describe recordings using hybrid electrodes, containing both micro- and clinical macroelectrodes, to simultaneously sample both large-scale network oscillations and single neuron spiking activity in the medial temporal lobe structures of human subjects during a visual recognition memory task. We quantify and compare single neuron unit activity (SUA) with high-frequency macrofield oscillations (HFOs) for decoding visual images. RESULTS: SUA and HFOs were recorded using hybrid electrodes containing both micro and macroelectrode contacts, implanted in patients with focal epilepsy. Decoding of image properties in different task trials was performed, analyzing SUA and HFO as point processes to capture the dynamics of neurons and their assemblies at different spatiotemporal scales, ranging from submillisecond discharges of single units to fast oscillations across large neuronal populations. Results highlight the limitations and potential complementary use of SUA and HFOs for decoding of general image properties. CONCLUSION: The dynamics of SUA and HFOs can be used to explore a wide range of neuronal assembly activities engaged in human memory processing. SIGNIFICANCE: Hybrid electrodes provide a technological bridge for exploring multiscale activity, spanning individual neurons, their assemblies, and large-scale population activity reflected in local field potentials. Analysis of SUA and HFO dynamics as point processes provides a potentially useful signal processing method for exploring the neuronal correlates operating at different spatial scales.


Assuntos
Encéfalo/fisiologia , Eletroencefalografia/métodos , Memória/fisiologia , Neurônios/fisiologia , Potenciais de Ação/fisiologia , Adulto , Feminino , Humanos , Masculino , Processamento de Sinais Assistido por Computador , Análise e Desempenho de Tarefas , Percepção Visual
17.
Rev Sci Instrum ; 86(1): 016111, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25638138

RESUMO

Using an ultrafast laser and a precision mask, we demonstrate that time signals picked off directly from a microchannel plate detector depend on the position of the hit. This causes a time spread of about 280 ps, which can affect the quality of imaging measurements using large detectors.

18.
Semin Oncol ; 18(1 Suppl 3): 25-33, 1991 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2003225

RESUMO

Cisplatin-based chemotherapy has most recently emerged as among the most active combinations for patients with disseminated or locally unresectable adenocarcinoma of the stomach. This article provides the historical framework for understanding these trials. It reviews the results of clinical trials using cisplatin alone or in combination in almost 600 patients. Because a recent German trial has suggested that cisplatin in combination with etoposide and doxorubicin increases gastric cancer resection rates, the rationale for cisplatin combination therapy in the neoadjuvant setting now has a foundation. Preliminary results from such a neoadjuvant approach used at the University of Southern California Medical Center are discussed. Finally, new areas of clinical and laboratory research in the treatment of gastric cancer are outlined as possibilities for future studies of the therapy of gastric cancer.


Assuntos
Adenocarcinoma/tratamento farmacológico , Cisplatino/uso terapêutico , Neoplasias Gástricas/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Humanos
19.
Semin Oncol ; 18(1 Suppl 3): 64-72, 1991 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2003229

RESUMO

This article reviews the rationale for chemotherapy (especially cisplatin-based treatments) in the management of epidermoid tumors of the esophagus. It focuses on the history of cisplatin and cisplatin-based combinations in the treatment of metastatic and localized esophageal cancers. The seminal chemotherapy trials of investigators at Memorial Sloan Kettering Cancer Center are reviewed and placed into perspective as a body of work that systematically measured the effects of chemotherapy in the treatment of primary tumors within the esophagus. The Wayne State University (Detroit, MI) program and subsequent similar programs, combining chemotherapy with concomitant radiation, are also reviewed and placed into historical context. Recently completed prospectively randomized cooperative group trials have now shown that chemotherapy in addition to radiation improves survival of patients with localized esophageal cancers versus radiation alone. While no standard chemotherapeutic regimen has come to the fore, chemotherapy clearly has a role in the curative treatment of epidermoid tumors of the esophagus.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Cisplatino/administração & dosagem , Neoplasias Esofágicas/tratamento farmacológico , Terapia Combinada , Humanos
20.
J Thorac Cardiovasc Surg ; 82(1): 147-9, 1981 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-6972472

RESUMO

A 70-year-old woman with calcific aortic stenosis and a calcific ascending aorta obtained excellent relief with a left ventricular--abdominal aortic conduit (a Dacron graft containing a porcine valve). Eight months postoperatively, erosion of the conduit into the stomach resulted in fatal gastrointestinal bleeding. This lethal complication may be averted by use of suggested techniques.


Assuntos
Aorta/cirurgia , Bioprótese , Gastrite/etiologia , Hemorragia Gastrointestinal/etiologia , Idoso , Aorta/patologia , Bioprótese/efeitos adversos , Feminino , Ventrículos do Coração/cirurgia , Humanos
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