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1.
J Nematol ; 52: 1-7, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32180376

RESUMO

Easter lily bulbs for greenhouse forcing are produced in Del Norte County, California and Curry County, Oregon, USA. Pratylenchus penetrans infestation seriously affects growth of field grown bulbs. During two consecutive years of field trials containing 22 treatments, commercially prepared formulations of essential oils (EOs) were compared to an untreated control and to a standard chemical fumigant treatment (FU) (1,3-dichloropropene and metam sodium) applied preplant followed by phorate (PH) at planting to determine their value in the management of lesion nematode, and in improving plant health. The EO products Duogard, EF400, EF300, and Cinnamite were tested as preplant dips to bulblet planting stock. The treated bulblets were tested either alone, in combination with PH at-planting, at planting following FU or in combination with PH at planting following FU. The organophosphates ethoprop and fosthiazate were also tested either alone, or at a reduced rate in combination with a reduced rate of PH. With respect to bulb circumference, ten treatments consistently outperformed the control. In consecutive years, three treatments had healthier looking roots than the control. At harvest, levels of lesion nematode within roots were consistently lower in nine treatments. EOs were beneficial in mitigating nematode damage.Easter lily bulbs for greenhouse forcing are produced in Del Norte County, California and Curry County, Oregon, USA. Pratylenchus penetrans infestation seriously affects growth of field grown bulbs. During two consecutive years of field trials containing 22 treatments, commercially prepared formulations of essential oils (EOs) were compared to an untreated control and to a standard chemical fumigant treatment (FU) (1,3-dichloropropene and metam sodium) applied preplant followed by phorate (PH) at planting to determine their value in the management of lesion nematode, and in improving plant health. The EO products Duogard, EF400, EF300, and Cinnamite were tested as preplant dips to bulblet planting stock. The treated bulblets were tested either alone, in combination with PH at-planting, at planting following FU or in combination with PH at planting following FU. The organophosphates ethoprop and fosthiazate were also tested either alone, or at a reduced rate in combination with a reduced rate of PH. With respect to bulb circumference, ten treatments consistently outperformed the control. In consecutive years, three treatments had healthier looking roots than the control. At harvest, levels of lesion nematode within roots were consistently lower in nine treatments. EOs were beneficial in mitigating nematode damage.

2.
Entropy (Basel) ; 22(1)2020 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-33285887

RESUMO

We show that random oblivious transfer protocols that are statistically secure according to a definition based on a list of information-theoretical properties are also statistically universally composable. That is, they are simulatable secure with an unlimited adversary, an unlimited simulator, and an unlimited environment machine. Our result implies that several previous oblivious transfer protocols in the literature that were proven secure under weaker, non-composable definitions of security can actually be used in arbitrary statistically secure applications without lowering the security.

3.
Osteoporos Int ; 30(7): 1529-1531, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30887076

RESUMO

PURPOSE: T50 is a novel serum-based marker that assesses the propensity of calcification in serum. Shorter T50 indicates greater propensity to calcify and it has been associated to cardiovascular disease (CVD) and mortality among patients with kidney disease. In the general population, neither the correlates of T50 nor the relationships of T50 with bone mineral density (BMD) are known. METHODS: We performed a nested cross-sectional study selecting 150 individuals at random among participants from the Osteoporotic Fractures in Men (MrOS) Study, a study of community-living older men. We categorized individuals into tertiles of T50 and compared demographics and disease indicators across tertiles. We utilized linear regression to evaluate the cross-sectional association between T50 and hip and spine BMD in multivariable models. RESULTS: Older age was associated with shorter T50. Kidney function tended to be lower in those with shorter T50 and the prevalence of CVD and peripheral arterial disease in those with shorter T50, albeit these findings did not achieve statistical significance. We found no statistically significant associations between T50 and total hip or total spine BMD in either unadjusted or multivariable adjusted models. CONCLUSIONS: T50, a novel indicator of serum calcification propensity, is not associated with BMD in community-living older men. Future larger studies should determine if T50 may give insights to CVD in the general population above and beyond traditional risk factors.


Assuntos
Densidade Óssea/fisiologia , Osteoporose/sangue , Fraturas por Osteoporose/sangue , Idoso , Biomarcadores/sangue , Calcinose/sangue , Calcinose/fisiopatologia , Estudos Transversais , Articulação do Quadril/fisiopatologia , Humanos , Vida Independente , Rim/fisiopatologia , Masculino , Pessoa de Meia-Idade , Complexos Multiproteicos/sangue , Nanopartículas/metabolismo , Osteoporose/fisiopatologia , Fraturas por Osteoporose/fisiopatologia
4.
Dis Esophagus ; 30(10): 1-7, 2017 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-28859385

RESUMO

Robotic-assisted transhiatal esophagectomy (RATE) is a technically complex procedure with potential for improved postoperative outcomes. In this report, we describe our experience with RATE in a large case series. A retrospective review was conducted to collect clinical, outcomes, and survival data for 100 consecutive patients with esophageal cancer (n = 98) and benign (n = 2) conditions undergoing RATE between March 2007 and December 2014. Progression-free (PFS) and overall (OS) survival were estimated using the Kaplan-Meier curves with comparisons by log-rank tests. Median operative time and estimated blood loss were 264 minutes and 75 mL, respectively. Median intensive care unit stay was 1 day and median length of hospital stay was 8 days. Postoperative complications commonly observed were nonmalignant pleural effusion (38%) and recurrent laryngeal nerve injury (33%); 30 day mortality rate was 2%. Median number of lymph nodes removed during RATE was 17 and R0 resection was achieved in 97.8% patients. At the end of the median follow-up period of 27.7 months, median PFS was 41 months and median OS was 54 months. 1-year and 3-year PFS rates were 82% (95% CI, 75%-89%) and 53% (95% CI, 42%-62%), respectively, and OS rates were 95% (95% CI, 91%-99%) and 57% (95% CI, 46%-67%). In our experience, RATE is an effective and safe oncologic surgical procedure in a carefully selected group of patients with acceptable operative time, minimal blood loss, standard postoperative morbidity and adequate PFS and OS profiles.


Assuntos
Adenocarcinoma/cirurgia , Carcinoma de Células Escamosas/cirurgia , Neoplasias Esofágicas/cirurgia , Esofagectomia/métodos , Procedimentos Cirúrgicos Robóticos/métodos , Adenocarcinoma/secundário , Adenocarcinoma/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Perda Sanguínea Cirúrgica , Carcinoma de Células Escamosas/secundário , Carcinoma de Células Escamosas/terapia , Quimiorradioterapia Adjuvante , Intervalo Livre de Doença , Neoplasias Esofágicas/patologia , Neoplasias Esofágicas/terapia , Esofagectomia/efeitos adversos , Feminino , Humanos , Unidades de Terapia Intensiva , Estimativa de Kaplan-Meier , Tempo de Internação , Excisão de Linfonodo , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante , Neoplasia Residual , Duração da Cirurgia , Derrame Pleural/etiologia , Traumatismos do Nervo Laríngeo Recorrente/etiologia , Estudos Retrospectivos , Procedimentos Cirúrgicos Robóticos/efeitos adversos , Taxa de Sobrevida , Resultado do Tratamento
5.
Bioinformatics ; 28(12): 1598-603, 2012 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-22500001

RESUMO

MOTIVATION: Existing microarray genotype-calling algorithms adopt either SNP-by-SNP (SNP-wise) or sample-by-sample (sample-wise) approaches to calling. We have developed a novel genotype-calling algorithm for the Illumina platform, optiCall, that uses both SNP-wise and sample-wise calling to more accurately ascertain genotypes at rare, low-frequency and common variants. RESULTS: Using data from 4537 individuals from the 1958 British Birth Cohort genotyped on the Immunochip, we estimate the proportion of SNPs lost to downstream analysis due to false quality control failures, and rare variants misclassified as monomorphic, is only 1.38% with optiCall, in comparison to 3.87, 7.85 and 4.09% for Illuminus, GenoSNP and GenCall, respectively. We show that optiCall accurately captures rare variants and can correctly account for SNPs where probe intensity clouds are shifted from their expected positions. AVAILABILITY AND IMPLEMENTATION: optiCall is implemented in C++ for use on UNIX operating systems and is available for download at http://www.sanger.ac.uk/resources/software/opticall/.


Assuntos
Algoritmos , Genótipo , Polimorfismo de Nucleotídeo Único , Software , Análise por Conglomerados , Estudos de Associação Genética , Humanos , Modelos Estatísticos , Análise de Sequência com Séries de Oligonucleotídeos
6.
Diabetologia ; 55(5): 1295-303, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22322920

RESUMO

AIMS/HYPOTHESIS: Serum potassium has been found to be a significant predictor of diabetes risk, but the effect of dietary potassium on diabetes risk is not clear. We sought to determine if dietary potassium is associated with risk of incident type 2 diabetes in young adults. METHODS: We used data from the Coronary Artery Risk Development in Young Adults (CARDIA) Study. Potassium intake was measured by (1) an average of three 24 h urinary potassium collections at the 5-year study visit, and (2) the CARDIA dietary assessment instrument at baseline. Incident type 2 diabetes cases were ascertained on the basis of use of diabetes medication and laboratory measurements. Analyses were adjusted for relevant confounders including intake of fruit and vegetables and other dietary factors. RESULTS: Of 1,066 participants with urinary potassium measurements, 99 (9.3%) developed diabetes over 15 years of follow-up. In multivariate models, adults in the lowest urinary potassium quintile were more than twice as likely to develop diabetes as their counterparts in the highest quintile (HR 2.45; 95% CI 1.08, 5.59). Of 4,754 participants with dietary history measurements, 373 (7.8%) developed diabetes over 20 years of follow-up. In multivariate models, African-Americans had a significantly increased risk of diabetes with lower potassium intake, which was not found in whites. CONCLUSIONS/INTERPRETATION: Low dietary potassium is associated with increased risk of incident diabetes in African-Americans. Randomised clinical trials are needed to determine if potassium supplementation, from either dietary or pharmacological sources, could reduce the risk of diabetes, particularly in higher-risk populations.


Assuntos
Diabetes Mellitus Tipo 2/epidemiologia , Potássio na Dieta/administração & dosagem , Adulto , População Negra/estatística & dados numéricos , Diabetes Mellitus Tipo 2/etnologia , Diabetes Mellitus Tipo 2/urina , Feminino , Frutas , Humanos , Incidência , Estudos Longitudinais , Masculino , Potássio na Dieta/urina , Risco , Verduras , População Branca/estatística & dados numéricos
7.
BMC Med Genomics ; 14(1): 23, 2021 01 20.
Artigo em Inglês | MEDLINE | ID: mdl-33472626

RESUMO

BACKGROUND: In biomedical applications, valuable data is often split between owners who cannot openly share the data because of privacy regulations and concerns. Training machine learning models on the joint data without violating privacy is a major technology challenge that can be addressed by combining techniques from machine learning and cryptography. When collaboratively training machine learning models with the cryptographic technique named secure multi-party computation, the price paid for keeping the data of the owners private is an increase in computational cost and runtime. A careful choice of machine learning techniques, algorithmic and implementation optimizations are a necessity to enable practical secure machine learning over distributed data sets. Such optimizations can be tailored to the kind of data and Machine Learning problem at hand. METHODS: Our setup involves secure two-party computation protocols, along with a trusted initializer that distributes correlated randomness to the two computing parties. We use a gradient descent based algorithm for training a logistic regression like model with a clipped ReLu activation function, and we break down the algorithm into corresponding cryptographic protocols. Our main contributions are a new protocol for computing the activation function that requires neither secure comparison protocols nor Yao's garbled circuits, and a series of cryptographic engineering optimizations to improve the performance. RESULTS: For our largest gene expression data set, we train a model that requires over 7 billion secure multiplications; the training completes in about 26.90 s in a local area network. The implementation in this work is a further optimized version of the implementation with which we won first place in Track 4 of the iDASH 2019 secure genome analysis competition. CONCLUSIONS: In this paper, we present a secure logistic regression training protocol and its implementation, with a new subprotocol to securely compute the activation function. To the best of our knowledge, we present the fastest existing secure multi-party computation implementation for training logistic regression models on high dimensional genome data distributed across a local area network.


Assuntos
Genômica , Privacidade , Algoritmos , Segurança Computacional , Modelos Logísticos
8.
IEEE Trans Neural Syst Rehabil Eng ; 27(8): 1546-1555, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31283483

RESUMO

Machine learning (ML) is revolutionizing research and industry. Many ML applications rely on the use of large amounts of personal data for training and inference. Among the most intimate exploited data sources is electroencephalogram (EEG) data, a kind of data that is so rich with information that application developers can easily gain knowledge beyond the professed scope from unprotected EEG signals, including passwords, ATM PINs, and other intimate data. The challenge we address is how to engage in meaningful ML with EEG data while protecting the privacy of users. Hence, we propose cryptographic protocols based on secure multiparty computation (SMC) to perform linear regression over EEG signals from many users in a fully privacy-preserving (PP) fashion, i.e., such that each individual's EEG signals are not revealed to anyone else. To illustrate the potential of our secure framework, we show how it allows estimating the drowsiness of drivers from their EEG signals as would be possible in the unencrypted case, and at a very reasonable computational cost. Our solution is the first application of commodity-based SMC to EEG data, as well as the largest documented experiment of secret sharing-based SMC in general, namely, with 15 players involved in all the computations.


Assuntos
Interfaces Cérebro-Computador , Confidencialidade , Adulto , Algoritmos , Condução de Veículo , Segurança Computacional , Bases de Dados Factuais , Eletroencefalografia , Feminino , Humanos , Modelos Lineares , Masculino , Adulto Jovem
9.
Mucosal Immunol ; 11(2): 562-574, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29091079

RESUMO

Genetic defects that affect intestinal epithelial barrier function can present with very early-onset inflammatory bowel disease (VEOIBD). Using whole-genome sequencing, a novel hemizygous defect in NOX1 encoding NAPDH oxidase 1 was identified in a patient with ulcerative colitis-like VEOIBD. Exome screening of 1,878 pediatric patients identified further seven male inflammatory bowel disease (IBD) patients with rare NOX1 mutations. Loss-of-function was validated in p.N122H and p.T497A, and to a lesser degree in p.Y470H, p.R287Q, p.I67M, p.Q293R as well as the previously described p.P330S, and the common NOX1 SNP p.D360N (rs34688635) variant. The missense mutation p.N122H abrogated reactive oxygen species (ROS) production in cell lines, ex vivo colonic explants, and patient-derived colonic organoid cultures. Within colonic crypts, NOX1 constitutively generates a high level of ROS in the crypt lumen. Analysis of 9,513 controls and 11,140 IBD patients of non-Jewish European ancestry did not reveal an association between p.D360N and IBD. Our data suggest that loss-of-function variants in NOX1 do not cause a Mendelian disorder of high penetrance but are a context-specific modifier. Our results implicate that variants in NOX1 change brush border ROS within colonic crypts at the interface between the epithelium and luminal microbes.


Assuntos
Colo/fisiologia , Genes Modificadores/genética , Genótipo , Doenças Inflamatórias Intestinais/genética , NADPH Oxidase 1/genética , Animais , Criança , Pré-Escolar , Estudos de Associação Genética , Predisposição Genética para Doença , Genoma , Sequenciamento de Nucleotídeos em Larga Escala , Interações Hospedeiro-Patógeno , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Mutação de Sentido Incorreto/genética , Polimorfismo de Nucleotídeo Único , Espécies Reativas de Oxigênio/metabolismo
10.
Dev Biol (Basel) ; 123: 251-63; discussion 265-6, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16566451

RESUMO

PER.C6, a cell line derived from human embryonic retinal cells transformed with the Adenovirus Type 5 (Ad5) E1A and E1B genes, is used to produce E1-deleted Ad5 vectors such as the MRKAd5 HIV-1 gag vaccine. While whole, live PER.C6 cells are capable of growing as tumours when transplanted subcutaneously into immunodeficient nude mice at a high dosage, the process for vaccine production includes filtration steps and other methods which effectively preclude contamination by intact viable substrate cells. However, because of the neoplastic nature of this cell line, we carried out a series of investigations to assess the tumorigenic risk posed by residuals from the cell substrate in a vaccine. To address concerns about transmission of oncogenic DNA, we demonstrated that purified PER.C6 cellular DNA does not induce tumours in newborn hamsters or nude mice. To address concerns about other potential residuals, including hypothetical adventitious tumour viruses, we demonstrated that a PER.C6 cell lysate and a MRKAd5 HIV-1 gag vaccine produced on PER.C6 cells do not induce tumours in newborn hamsters or newborn rats. These results, in conjunction with the wide panel of viral safety tests performed on these cells, support the safety of the PER.C6 as a cell substrate for vaccine production.


Assuntos
Vacinas contra a AIDS/biossíntese , Adenovírus Humanos/genética , Vacinas contra a AIDS/normas , Animais , Animais Recém-Nascidos , Sequência de Bases , Testes de Carcinogenicidade , Linhagem Celular Transformada , Cricetinae , Primers do DNA , Vetores Genéticos , Células HeLa , Humanos , Camundongos , Camundongos Nus , Neoplasias/epidemiologia , Neoplasias/etiologia , Reação em Cadeia da Polimerase , Ratos , Retina/virologia
11.
Arch Neurol ; 56(12): 1509-11, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10593308

RESUMO

OBJECTIVE: To provide clinicoanatomical correlation for a small pontine tegmental ischemic stroke producing the one and one-half syndrome associated with supranuclear facial weakness. DESIGN: Case report. SETTING: Tertiary care center. PATIENT: A 70-year-old man developed left-sided facial weakness sparing the forehead, a left internuclear ophthalmoplegia, and a complete left horizontal gaze palsy immediately after percutaneous transluminal coronary angioplasty. Magnetic resonance imaging demonstrated a small lesion in the left paramedian aspect of the dorsal pontine tegmentum. MAIN OUTCOME AND RESULTS: Electromyographic findings were consistent with supranuclear facial involvement. The patient had nearly complete recovery after 1 year. CONCLUSIONS: To our knowledge, this is the first report of supranuclear facial weakness in association with the one and one-half syndrome. The location of the lesion provides evidence of the existence of corticofugal fibers that extend to the facial nucleus in the dorsal paramedian pontine tegmentum.


Assuntos
Paralisia Facial/patologia , Oftalmoplegia/patologia , Ponte/patologia , Acidente Vascular Cerebral/patologia , Idoso , Nervo Facial/patologia , Nervo Facial/fisiopatologia , Paralisia Facial/fisiopatologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Debilidade Muscular/patologia , Debilidade Muscular/fisiopatologia , Vias Neurais/patologia , Vias Neurais/fisiopatologia , Oftalmoplegia/fisiopatologia , Ponte/irrigação sanguínea , Ponte/fisiopatologia , Acidente Vascular Cerebral/fisiopatologia
12.
Psychol Bull ; 106(1): 74-96, 1989 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-2667010

RESUMO

Outlines 5 models of the temperature-aggression hypothesis: negative affect escape, simple negative affect, excitation transfer/misattribution, cognitive neoassociation, and physiological-thermoregulatory. Reviews relevant studies. Aggression measures include violent crime, spouse abuse, horn-honking, and delivery of electric shock. Analysis levels include geographic regional, seasonal, monthly, and daily variations in aggression, and concomitant temperature-aggression effects in field and laboratory settings. Field studies clearly show that heat increases aggression. Laboratory studies show inconsistencies, possibly because of several artifacts. Specific models have not been adequately tested, but the excitation transfer/misattribution and cognitive neoassociation approaches appear most promising, whereas the negative affect escape appears the least viable. Suggestions for future work are made.


Assuntos
Agressão/psicologia , Temperatura Alta/efeitos adversos , Violência , Nível de Alerta , Homicídio , Humanos
13.
Psychol Rev ; 108(1): 273-9, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11212630

RESUMO

Psychologists have often categorized human aggression as hostile or instrumental. Hostile aggression is "hot," impulsive behavior that is motivated by a desire to hurt someone; instrumental aggression is "cold," premeditated behavior used as a means to some other end. This dichotomy was useful to the early development of aggression theories and continues to capture important features of nonhuman aggression, but it has outlived its usefulness as a descriptor of fundamentally different kinds of human aggression. It is confounded with the automatic-controlled information-processing dichotomy, and it fails to consider aggressive acts with multiple motives. Knowledge structure models of aggression easily handle these problems. Taking extreme measures to preserve the hostile-instrumental dichotomy will delay further advances in understanding and controlling human aggression. Therefore, this seems a proper time to "pull the plug" and allow the hostile-instrumental aggression dichotomy a dignified death.


Assuntos
Agressão/psicologia , Teoria Psicológica , Pensamento , Ira , Humanos , Comportamento Impulsivo , Motivação
14.
AIDS Res Hum Retroviruses ; 10(7): 853-61, 1994 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7986590

RESUMO

Subunit vaccines based on recombinant proteins have proved useful for inducing antibody responses and they are safe for widespread use because they do not contain any live components. Unfortunately, they do not typically induce the types of cell-mediated immune responses required to control viral pathogens; specifically, they do not induce CD8+ cytotoxic T lymphocyte (CTL) responses. To increase the immunogenicity of recombinant proteins, we have used the QS-21 saponin adjuvant in subunit vaccine formulations. In the current study, experimental subunit vaccine formulations containing recombinant p55gag or gp120env proteins from the mac251 strain of the simian immunodeficiency virus (SIVmac251) and the QS-21 adjuvant were used to immunize rhesus macaques. These formulations induced SIV gag- or env-specific cellular immunity that was detectable in vitro and included killer cell activity. The induction of killer cells required prior vaccination and the responses were antigen specific for the immunogens contained in the vaccine formulations. Autologous target cells were required to detect these responses, suggesting genetic restriction, and effector cells appeared to be present in both the CD4+ and CD8+ T lymphocyte subpopulations. These data suggest that the vaccine-induced killer cell activity that was detected was mediated by both CD4+ and CD8+ lymphocytes. Despite the presence of these killer cells, all of the animals became infected with the SIVmac251 on experimental challenge. These findings demonstrated that antigen-specific killer cell responses could be induced by a subunit vaccine formulated with the QS-21 saponin adjuvant. The characteristics of the responses suggested that the effector cells were T lymphocytes, expressing either CD4 or CD8.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Linfócitos T CD4-Positivos/patologia , Linfócitos T CD8-Positivos/patologia , Vacinas contra a SAIDS/administração & dosagem , Saponinas/administração & dosagem , Síndrome de Imunodeficiência Adquirida dos Símios/prevenção & controle , Vírus da Imunodeficiência Símia/patogenicidade , Sequência de Aminoácidos , Animais , Genes env/imunologia , Genes gag/imunologia , Linfonodos/patologia , Macaca mulatta , Masculino , Dados de Sequência Molecular , Vacinas contra a SAIDS/genética , Vacinas contra a SAIDS/imunologia , Saponinas/imunologia , Vírus da Imunodeficiência Símia/genética , Vírus da Imunodeficiência Símia/imunologia , Vacinação
15.
Sleep ; 18(5): 325-9, 1995 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7676164

RESUMO

Clinical evidence indicates that swallowing, a vital function, may be impaired in sleep. To address this issue, we elicited swallows in awake and sleeping adult cats by injecting water through a nasopharyngeal tube. Our results indicate that swallowing occurs not only in non-rapid eye movement (NREM) sleep, but also in rapid eye movement (REM) sleep. In NREM sleep, the injections often caused arousal followed by swallowing, but, in the majority of cases, swallowing occurred in NREM sleep before arousal. These swallows in NREM sleep were entirely comparable to swallows in wakefulness. In contrast, the injections in REM sleep were less likely to cause arousal, and the swallows occurred as hypotonic events. Furthermore, apneas were sometimes elicited by the injections in REM sleep, and there was repetitive swallowing upon arousal. These results suggest that the hypotonic swallows of REM sleep were ineffective.


Assuntos
Gatos , Deglutição , Sono REM , Vigília , Animais , Apneia/complicações , Nível de Alerta , Transtornos de Deglutição/etiologia , Transtornos de Deglutição/fisiopatologia , Eletroencefalografia , Eletromiografia
16.
Sleep ; 19(6): 472-8, 1996 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8865504

RESUMO

The response to tracheal stimulation (50 microliters of tap water) during wakefulness, non-rapid eye movement (NREM) sleep and rapid eye movement (REM) sleep was investigated in adult cats. In wakefulness, repetitive coughing occurred on 80% of the trials. In NREM and REM sleep, the most frequent response (approximately 69% and 58% of the trials, respectively) was arousal, followed by coughing. Apneas occurred following the stimulus and before arousal in 11% and 24% of the trials in NREM and REM sleep, respectively. In NREM sleep, the tracheal stimulus sometimes evoked expiratory efforts following a normal inspiratory effort (11% of the trials). These were much weaker than the expiratory efforts during coughing in wakefulness. In REM sleep, stimulation in 11% of the trials elicited increased inspiratory efforts. Although these may have been diminutive preparatory inspirations for coughing, they were much smaller than preparatory inspirations associated with coughing in wakefulness, and they were never followed by active expiratory efforts. Arousal from either NREM or REM sleep in response to tracheal stimulation was sometimes associated with an augmented breath. This response, which is common upon spontaneous arousal, may lead to deeper aspiration of the tracheal fluid. We conclude that in cats coughing requires wakefulness and that airway stimuli in sleep cause a variety of respiratory responses, some of which may be maladaptive.


Assuntos
Respiração/fisiologia , Sono/fisiologia , Traqueia/fisiologia , Vigília/fisiologia , Animais , Gatos , Estimulação Física , Polissonografia
17.
J Thorac Cardiovasc Surg ; 127(1): 185-92, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14752430

RESUMO

OBJECTIVE: We sought to assess the feasibility of performing sutureless distal coronary artery bypass anastomoses with a novel magnetic coupling device. METHODS: From May 2000 to April 2001, single-vessel side-to-side coronary artery bypass grafting on a beating heart was performed in 39 domestic white pigs (35-60 kg) without the use of mechanical stabilization, shunts, or perfusion bridges. Animals were divided into 2 groups. Seventeen pigs underwent right internal thoracic artery to right coronary artery bypass grafting through a median sternotomy (group 1) with a novel magnetic vascular positioning system (MVP system; Ventrica, Inc, Fremont, Calif). Twenty-two pigs underwent left internal thoracic artery to left anterior descending artery grafting with the MVP anastomotic device through a left anterior minithoracotomy (group 2). This system consists of 2 pairs of elliptical magnetic implants and a deployment device. One pair of magnets forms the anastomotic docking port within the graft; the other pair forms an identical anastomotic docking port within the target vessel. The anastomosis is created when the 2 docking ports magnetically couple. Anastomotic patency was evaluated by means of angiography during the first postoperative week and at 1 month. Histologic studies were performed at different time points as late as 6 months. RESULTS: Right internal thoracic artery to right coronary artery anastomoses and left internal thoracic artery to left anterior descending artery anastomoses were successfully performed with the system in all animals. The self-adherent and self-aligning properties of the implants allowed for immediate and secure approximation of the arteries (total anastomotic time between 2-3 minutes). Anastomoses were constructed without a stabilization platform. Five nondevice-related deaths occurred postoperatively. One-week angiography, performed in 35 surviving animals, showed a patent graft and anastomosis in all cases. The patency rate at 1 month was 97% (33/34). Histologic studies as late as 6 months demonstrated neointimal coverage of the magnets without any significant luminal obstruction. Histology also confirmed the presence of viable tissue between magnets. CONCLUSION: The MVP anastomotic system uses magnetic force to create rapid and secure distal coronary artery anastomoses, which might facilitate minimally invasive and totally endoscopic coronary artery bypass surgery.


Assuntos
Automação , Ponte de Artéria Coronária/instrumentação , Magnetismo , Artérias Torácicas/transplante , Anastomose Cirúrgica/instrumentação , Animais , Ponte de Artéria Coronária/métodos , Vasos Coronários/patologia , Desenho de Equipamento , Segurança de Equipamentos , Feminino , Rejeição de Enxerto , Sobrevivência de Enxerto , Imuno-Histoquímica , Masculino , Modelos Animais , Sensibilidade e Especificidade , Instrumentos Cirúrgicos , Sus scrofa , Grau de Desobstrução Vascular
18.
J Appl Physiol (1985) ; 81(2): 751-60, 1996 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8872643

RESUMO

Diaphragmatic electromyograms from five adult cats were studied to determine whether diaphragmatic activity, like central respiratory activity, increases in rapid-eye-movement (REM) sleep. Breaths with inspiratory durations between 250 and 2,000 ms were analyzed. 1) There was a greater slope of the moving time average of diaphragmatic activity in REM than in non-REM (NREM) sleep. These greater slopes occurred whether the route of breathing was through the upper airways or through an endotracheal tube and may have resulted from early recruitment of motor units. 2) Mean diaphragmatic activity was also greater, but other variables (peak activity, the area under the curve of diaphragmatic activity, mean intratracheal pressures, inspiratory airflow rates, and tidal volumes) were not greater in REM than in NREM sleep. 3) Diaphragmatic activity was similar in REM sleep and active wakefulness. 4) Across states, slope of the moving time average varied with the duration of inspiration: greater slopes were associated with shorter breaths. These results are consistent with an increase in central respiratory drive in REM sleep that increases the rate of rise of diaphragmatic activity.


Assuntos
Diafragma/fisiologia , Sono REM/fisiologia , Resistência das Vias Respiratórias/fisiologia , Animais , Gatos , Diafragma/inervação , Eletroencefalografia , Eletromiografia , Intubação Intratraqueal , Postura/fisiologia , Mecânica Respiratória/fisiologia
19.
Science ; 224(4656): 1382, 1984 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-17793355
20.
Behav Brain Res ; 3(1): 1-22, 1981 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7248062

RESUMO

These experiments determined the extent to which the hippocampal system and the medial frontal cortex are selectively involved in cognitive mapping in spatial environments. Rats were trained to discriminate between two 3-dimensional objects based on either the location of the objects in the test environment, or on the stimulus characteristics of the objects themselves. Following the acquisition of one of these discrimination tasks, each rat was given a series of transfer tests to determine the extent to which a cognitive mapping strategy had been used to solve the task. Each rat was then given a lesion in the fimbria-fornix or the medial frontal cortex, or a control operation. In the location discrimination, rats with fimbria-fornix lesions, as compared to control rats: (a) performed poorly at the beginning of retention testing; (b) relearned the task to criterion performance; (c) performed normally during the transfer tests indicating that they used a cognitive mapping strategy, and (d) performed poorly in the discrimination reversals. In the object discrimination, these rats performed as well as controls during retention and transfer tests, but had a slight impairment during discrimination reversals. The performance of rats with lesions in the medial frontal cortex was worse than that of the controls during the retention of both discriminations, and during the reversal of the location, but not the object discrimination. These results are related to predictions of current theories implicating the hippocampus and medial frontal cortex in spatially organized behaviors, particularly those behaviors requiring cognitive mapping.


Assuntos
Cognição/fisiologia , Lobo Frontal/fisiologia , Hipocampo/fisiologia , Memória/fisiologia , Retenção Psicológica/fisiologia , Reversão de Aprendizagem/fisiologia , Animais , Mapeamento Encefálico , Aprendizagem por Discriminação/fisiologia , Percepção de Forma/fisiologia , Masculino , Orientação/fisiologia , Ratos , Núcleos Septais/fisiologia
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