869 resultados para Nikitenko, A. (Aleksandr), 1804 or 5-1877.
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Tese de doutoramento, Medicina Dentária (Medicina Dentária Preventiva e Comunitária), Universidade de Lisboa, Faculdade de Medicina Dentária, 2014
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Background: Children with spina bifida represent the major risk group for latex sensitization. Purpose: To determine the prevalence of latex sensitization in these children and to identify risk factors. Material and methods: We studied 57 patients with spina bifida. The mean age was 5.6 years and the male/female ratio was 0.8/1. In all patients a questionnaire, skin prick test (SPT) with latex (UCBStallergènes, Lofarma and ALK-Abelló), common aeroallergens and fruits (UCB-Stallergènes) and serum determination of total IgE (AlaSTAT) were performed. Results: The prevalence of latex sensitization was 30 %; only two sensitized children (12 %) had symptoms after exposure. Risk factors for latex sensitization were age 5 years (p = 0.008; OR = 6.0; 95% CI = 1.7-22.1), having at least four previous surgical interventions (p < 0.0001; OR = 18.5; 95% CI = 3.6-94.8), having undergone surgery in the first 3 months of life (p = 0.008; OR = 5.4; 95% CI = 0.7-29.2) and total serum IgE 44 IU/ml (p = 0.03; OR = 3.8; 95 %CI = 1.1-13.1). Multiple logistic regression analysis showed that only a history of four or more surgical interventions (p < 0.0001; OR = 26.3; 95 %CI = 2.9-234.2) and total serum IgE 44 IU/ml (p = 0.02; OR = 8.6; 95% CI = 1.4-53.4) were independently associated with latex sensitization. Sex, family and personal allergic history, hydrocephalus with ventriculoperitoneal shunt, cystourethrograms, intermittent bladder catheterization and atopy were not related to latex sensitization. Conclusions: In children with spina bifida, significant and independent risk factors identified for latex sensitization were multiple interventions and higher levels of total serum IgE. A prospective study will clarify the clinical evolution of assymptomatic children sensitized to latex.
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Em 2006, a IEA (Agência Internacional de Energia), publicou alguns estudos de consumos mundiais de energia. Naquela altura, apontava na fabricaão de produtos, um consumo mundial de energia elétrica, de origem fóssil de cerca 86,16 EJ/ano (86,16×018 J) e um consumo de energia nos sistemas de vapor de 32,75 EJ/ano. Evidenciou também nesses estudos que o potencial de poupança de energia nos sistemas de vapor era de 3,27 EJ/ano. Ou seja, quase tanto como a energia consumida nos sistemas de vapor da U.E. Não se encontraram números relativamente a Portugal, mas comparativamente com outros Pases publicitados com alguma similaridade, o consumo de energia em vapor rondará 0,2 EJ/ano e por conseguinte um potencial de poupança de cerca 0,02 EJ/ano, ou 5,6 × 106 MWh/ano ou uma potência de 646 MW, mais do que a potência de cinco barragens Crestuma/Lever! Trata-se efetivamente de muita energia; interessa por isso perceber o onde e o porquê deste desperdício. De um modo muito modesto, pretende-se com este trabalho dar algum contributo neste sentido. Procurou-se evidenciar as possibilidades reais de os utilizadores de vapor de água na indústria reduzirem os consumos de energia associados à sua produção. Não estão em causa as diferentes formas de energia para a geraão de vapor, sejam de origem fóssil ou renovável; interessou neste trabalho estudar o modo de como é manuseado o vapor na sua função de transporte de energia térmica, e de como este poderá ser melhorado na sua eficiência de cedência de calor, idealmente com menor consumo de energia. Com efeito, de que servirá se se optou por substituir o tipo de queima para uma mais sustentável se a jusante se continuarem a verificarem desperdícios, descarga exagerada nas purgas das caldeiras com perda de calor associada, emissões permanentes de vapor para a atmosfera em tanques de condensado, perdas por válvulas nos vedantes, purgadores avariados abertos, pressão de vapor exageradamente alta atendendo às temperaturas necessárias, “layouts” do sistema de distribuição mal desenhados, inexistência de registos de produção e consumos de vapor, etc. A base de organizaão deste estudo foi o ciclo de vapor: produção, distribuição, consumo e recuperaão de condensado. Pareceu importante incluir também o tratamento de água, atendendo às implicaões na transferência de calor das superfícies com incrustaões. Na produção de vapor, verifica-se que os maiores problemas de perda de energia têm a ver com a falta de controlo, no excesso de ar e purgas das caldeiras em exagero. Na distribuição de vapor aborda-se o dimensionamento das tubagens, necessidade de purgas a v montante das válvulas de controlo, a redução de pressão com válvulas redutoras tradicionais; será de destacar a experiência americana no uso de micro turbinas para a redução de pressão com produção simultânea de eletricidade. Em Portugal não se conhecem instalaões com esta opção. Fabricantes da República Checa e Áustria, têm tido sucesso em algumas dezenas de instalaões de redução de pressão em diversos pases europeus (UK, Alemanha, R. Checa, França, etc.). Para determinaão de consumos de vapor, para projeto ou mesmo para estimativa em máquinas existentes, disponibiliza-se uma série de equaões para os casos mais comuns. Dá-se especial relevo ao problema que se verifica numa grande percentagem de permutadores de calor, que é a estagnaão de condensado - “stalled conditions”. Tenta-se também evidenciar as vantagens da recuperaão de vapor de flash (infelizmente de pouca tradição em Portugal), e a aplicaão de termocompressores. Finalmente aborda-se o benchmarking e monitorizaão, quer dos custos de vapor quer dos consumos específicos dos produtos. Esta abordagem é algo ligeira, por manifesta falta de estudos publicados. Como trabalhos práticos, foram efetuados levantamentos a instalaões de vapor em diversos sectores de atividades; 1. ISEP - Laboratório de Química. Porto, 2. Prio Energy - Fábrica de Biocombustíveis. Porto de Aveiro. 3. Inapal Plásticos. Componentes de Automóvel. Leça do Balio, 4. Malhas Sonix. Tinturaria Têxtil. Barcelos, 5. Uma instalaão de cartão canelado e uma instalaão de alimentos derivados de soja. Também se inclui um estudo comparativo de custos de vapor usado nos hospitais: quando produzido por geradores de vapor com queima de combustível e quando é produzido por pequenos geradores elétricos. Os resultados estão resumidos em tabelas e conclui-se que se o potencial de poupança se aproxima do referido no início deste trabalho.
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STUDY OBJECTIVE: The main aim of this study is to evaluate the impact of adolescent pregnancy in the future contraceptive choices. A secondary aim is to verify whether these choices differ from those made after an abortion. DESIGN: Retrospective study. SETTING:Adolescent Unit of a tertiary care center. PARTICIPANTS:212 pregnant teenagers. INTERVENTIONS: Medical records review. MAIN OUTCOME MEASURES:Intended pregnancy rate and contraceptive methods used before and after pregnancy. For contraceptive choices after pregnancy we considered: Group 1 - teenagers who continued their pregnancy to delivery (n = 106) and Group 2 - the same number of adolescents who chose to terminate their pregnancy. RESULTS: The intended pregnancy rate was 14.2%. Prior to a pregnancy continued to delivery, the most widely used contraceptive method was the male condom (50.9%), followed by oral combined contraceptives (28.3%); 18.9% of adolescents were not using any contraceptive method. After pregnancy, contraceptive implant was chosen by 70.8% of subjects (P < .001) and the oral combined contraceptives remained the second most frequent option (17.9%, P = .058). Comparing these results with Group 2, we found that the outcome of the pregnancy was the main factor in the choices that were made. Thus, after a pregnancy continued to delivery, adolescents prefer the use of LARC [78.4% vs 40.5%, OR: 5,958 - 95% (2.914-12.181), P < .001)], especially contraceptive implants [70.8% vs 38.7%, OR: 4.371 - 95% (2.224-8.591), P < .001], to oral combined contraceptives [17.9% vs 57.5%, OR: 0.118 - 95% CI (0.054-0.258), P < .001]. CONCLUSION:Adolescent pregnancy and its outcome constitute a factor of change in future contraceptive choice.
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RESUMO - Introdução: Actualmente 11,3 milhões de indivíduos estão co-infectados pela Tuberculose/Vírus Imunodeficiência Humana (TB/VIH), uma das principais causas de incapacidade e morte no mundo. É determinada pela exposição dos indivíduos aos factores de risco e condições/determinantes sociais de sade. Várias são as medidas criadas a nível nacional e internacional na luta contra TB e a infecção VIH. Objectivo: Caracterizar e comparar os casos de TB entre os indivíduos não infectados com VIH e os infectados com VIH, considerando as características sócio-demográficas, o tratamento, patologias associadas e factores de risco. Método: Estudo descritivo, quantitativo e observacional. A informaão foi obtida a partir da base de dados do Sistema Nacional de Vigilância Epidemiológica da Tuberculose dos casos de TB notificados entre 1 de Janeiro de 2008 a 31 de Dezembro de 2009. Para tratamento e análise estatística (descritiva e inferencial) o programa usado foi o SPSS versão 18,0. Resultados: 12,8% dos indivíduos estavam co-infectados com TB/VIH e 87,2% não estavam co-infectados. A presença de VIH nos casos de tuberculose apresenta evidência de relaão com quase todas variáveis em estudo (p<0,00) excepto a presença de insuficiência renal (p<0,307). Apresentam maior probalidade de risco da co-infecção TB/VIH os homens, a faixa etária [35;44[, os estrangeiros, os desempregados, estar em retratamento e fumar. Os indivíduos com Doença Hepática (OR= 5,238; IC95%: 3,706;7,403; ORA = 3,104; IC95%: 2,164;4,454), patologias associadas (OR=13,199; IC95%: 11,246; 15,491; ORA=21,348; IC95%:17,569; 25,940) e factores de risco (OR=3,237; IC95%: 2,968; 3,531; ORA=2,644; IC95%: 2,414; 2,985) tem maior probalidade da co-infecção TB/VIH. O ajustamento para o sexo e a idade interferiu em todas variáveis em estudo. Conclusão: Os homens, da faixa etária [35;44 [, desempregados, estrangeiros, em retratamento, fumadores apresentam maior probalidade de risco de estar co-infectado com TB/VIH.
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RESUMO - Contexto: As desigualdades sociais em sade são uma questão central de justiça social. No contexto de forte envelhecimento populacional em Portugal, as desigualdades nos idosos representam um desafio crucial para o futuro, sobre as quais existe pouca evidência. Este estudo pretende investigar a existência de desigualdades socioeconómicas em sade nos idosos, em Portugal. Metodologia: Foram utilizados os dados para Portugal, da quarta vaga do Survey of Health, Ageing and Retirement in Europe. O estudo engloba 2017 indivíduos com 50 ou mais anos. Foram utilizados quatro indicadores de sade: problemas de sade, sade auto-reportada, doenças de longa duraão e atividade limitada. Foi utilizado o nível de educaão como indicador socioeconómico. As desigualdades socioeconómicas foram avaliadas através de regressões logísticas multivariadas. Resultados: Existem desigualdades socioeconómicas em sade nos idosos favoráveis aos mais educados. Os indivíduos com menor educaão estão em maior risco de reportar má sade (OR=5,5); maior risco em ter problemas de sade, existindo um gradiente social na Hipertensão Arterial (OR=2,4) e na Artrite (OR=7,0); maior risco de doenças de longa duraão (OR=1,6) e maior risco de limitaão nas atividades diárias (OR=5,1). As desigualdades socioeconómicas diminuem com a idade. Conclusão: De forma a melhorar a sade e reduzir as desigualdades socioeconómicas em sade nos idosos, os resultados apontam para a necessidade de implementar medidas no âmbito dos problemas de sade em que existe um gradiente social, melhorar o nível de educaão da populaão geral e implementar medidas de educaão para a sade, aumentando a literacia em sade nos idosos mais jovens.
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BACKGROUND & AIMS: Hepatitis C virus (HCV) induces chronic infection in 50% to 80% of infected persons; approximately 50% of these do not respond to therapy. We performed a genome-wide association study to screen for host genetic determinants of HCV persistence and response to therapy. METHODS: The analysis included 1362 individuals: 1015 with chronic hepatitis C and 347 who spontaneously cleared the virus (448 were coinfected with human immunodeficiency virus [HIV]). Responses to pegylated interferon alfa and ribavirin were assessed in 465 individuals. Associations between more than 500,000 single nucleotide polymorphisms (SNPs) and outcomes were assessed by multivariate logistic regression. RESULTS: Chronic hepatitis C was associated with SNPs in the IL28B locus, which encodes the antiviral cytokine interferon lambda. The rs8099917 minor allele was associated with progression to chronic HCV infection (odds ratio [OR], 2.31; 95% confidence interval [CI], 1.74-3.06; P = 6.07 x 10(-9)). The association was observed in HCV mono-infected (OR, 2.49; 95% CI, 1.64-3.79; P = 1.96 x 10(-5)) and HCV/HIV coinfected individuals (OR, 2.16; 95% CI, 1.47-3.18; P = 8.24 x 10(-5)). rs8099917 was also associated with failure to respond to therapy (OR, 5.19; 95% CI, 2.90-9.30; P = 3.11 x 10(-8)), with the strongest effects in patients with HCV genotype 1 or 4. This risk allele was identified in 24% of individuals with spontaneous HCV clearance, 32% of chronically infected patients who responded to therapy, and 58% who did not respond (P = 3.2 x 10(-10)). Resequencing of IL28B identified distinct haplotypes that were associated with the clinical phenotype. CONCLUSIONS: The association of the IL28B locus with natural and treatment-associated control of HCV indicates the importance of innate immunity and interferon lambda in the pathogenesis of HCV infection.
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BACKGROUND: Excision and primary midline closure for pilonidal disease (PD) is a simple procedure; however, it is frequently complicated by infection and prolonged healing. The aim of this study was to analyze risk factors for surgical site infection (SSI) in this context. METHODS: All consecutive patients undergoing excision and primary closure for PD from January 2002 through October 2008 were retrospectively assessed. The end points were SSI, as defined by the Center for Disease Control, and time to healing. Univariable and multivariable risk factor analyses were performed. RESULTS: One hundred thirty-one patients were included [97 men (74%), median age = 24 (range 15-66) years]. SSI occurred in 41 (31%) patients. Median time to healing was 20 days (range 12-76) in patients without SSI and 62 days (range 20-176) in patients with SSI (P < 0.0001). In univariable and multivariable analyses, smoking [OR = 2.6 (95% CI 1.02, 6.8), P = 0.046] and lack of antibiotic prophylaxis [OR = 5.6 (95% CI 2.5, 14.3), P = 0.001] were significant predictors for SSI. Adjusted for SSI, age over 25 was a significant predictor of prolonged healing. CONCLUSION: This study suggests that the rate of SSI after excision and primary closure of PD is higher in smokers and could be reduced by antibiotic prophylaxis. SSI significantly prolongs healing time, particularly in patients over 25 years.
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BACKGROUND: The impact of preoperative impaired left ventricular ejection fraction (EF) in octogenarians following coronary bypass surgery on short-term survival was evaluated in this study. METHODS: A total of 147 octogenarians (mean age 82.1 ± 1.9 years) with coronary artery diseases underwent elective coronary artery bypass graft between January 2000 and December 2009. Patients were stratified into: Group I (n = 59) with EF >50%, Group II (n = 59) with 50% > EF >30% and in Group III (n = 29) with 30% > EF. RESULTS: There was no difference among the three groups regarding incidence of COPD, renal failure, congestive heart failure, diabetes, and preoperative cerebrovascular events. Postoperative atrial fibrillation was the sole independent predictive factor for in-hospital mortality (odds ratio (OR), 18.1); this was 8.5% in Group I, 15.3% in Group II and 10.3% in Group III. Independent predictive factors for mortality during follow up were: decrease of EF during follow-up for more that 5% (OR, 5.2), usage of left internal mammary artery as free graft (OR, 18.1), and EF in follow-up lower than 40% (OR, 4.8). CONCLUSIONS: The results herein suggest acceptable in-hospital as well short-term mortality in octogenarians with impaired EF following coronary artery bypass grafting (CABG) and are comparable to recent literature where the mortality of younger patients was up to 15% and short-term mortality up to 40%, respectively. Accordingly, we can also state that in an octogenarian cohort with impaired EF, CABG is a viable treatment with acceptable mortality.
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To investigate the prevalence and risk factors of perceived diabetes-related discrimination in the workplace and in work-related insurances in persons with diabetes mellitus in Switzerland. 509 insulin-treated diabetic subjects representative of the northwestern Swiss population responded to a self-report questionnaire on perceived diabetes-related discrimination in the workplace and in work-related insurances (salary loss insurance, supplementary occupational plan). Discrimination was defined as being treated differently at least once in relation to diabetes. The reported rates of different aspects of discrimination in the workplace and in work-related insurances ranged between 5-11% and 4-15% respectively. Risk factors that independently increased the risk of not being hired due to diabetes were the presence of at least two severe hypoglycaemic events/year and relevant diabetic complications (OR 5.6 and OR 2.6 respectively; both<0.05). The presence of at least two severe hypoglycaemic events/year was also associated with an increased risk of losing one's job (OR 6.5, <0.01). Overweight or obesity were related to increased discrimination in work-related insurances (OR for denial 2.1-2.4; OR for reserve 3.9-4.4; all<0.05). Perceived diabetes-related discrimination in the workplace and by work-related insurances is a common problem. In the light of our findings the introduction of effective non-discrimination legislation for patients with chronic illnesses appears to be desirable.
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Contient : 1° « Les Vies et passions des apostres Nostres Seigneur Jhesu Crist et d'aucuns aultres sains et sainttes, et aussi pluseurs miracles que Nostre Dame fist pour ceulx et celles qui devotement la deprierent et requirent », en prose ; 2° Exhortation à l'amour de Dieu ; 3° « De sant Bonet, qui fut evesques de Clarmont » ; 4° « De Moz que Nostre Dame revela a.I. sien ami en letres d'or » ; 5° « D'une Pucelle qui ere suer.I. prevoire que Nostre Dame veut avoir » ; 6° « Come Nostre Dame racorda Theophile à son chior fil » ; 7° Treize Miracles de Notre-Dame [de GAUTIER DE COINCY], savoir ; 8° Sermon sur la pénitence ; 9° « La Vie de sainte Agathe » ; 10° Vers sur la mort, attribués par les uns à HELINAND et par les autres à THIBAUT, de Marly ; 11° « Li.X. Comandemans de la loi que chascons et chascone est tenus à garder » ; 12° « Li Clostra de l'arme » ; 13° Instruction pour bien vivre
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Contient : 1 à 19 Recueil de notes pour servir à l'usage journalier des travaux de la chambre des comptes ; 1 Comptes faits ; 2 Calendrier. En latin ; 3 « Festa mobilia camere compotorum ». En latin ; 4 « Reigle pour trouver le nombre de l'epacte et le nombre d'or » ; 5 Notes sur la manière de compter ; 6 Règle « pour calculer combien tant de deniers par jour font de livres par an » ; 7 Règle « pour departir une somme à plusieurs, au sol la livre » ; 8 « Ad sciendum dies Paschae, tam de preterito quam de futuro temporibus ». En latin ; 9 « Estimatio summarum reddituum per diem ad summas per annum, ad annos non bissextiles, ad quos bissextiles, ad summam unius diei ». En latin ; 10 Rapport des valeurs respectives des monnaies de France et d'Angleterre ; 11 Somme des « gaiges » par année ou par quartier d'un homme d'armes, soit à pied soit à cheval, et ce que prennent « le duc, le comte, le chevalier banneret, le chevalier bachelier, un archier » ; 12 « Provincie regni ». En latin ; 13 « Nomina ecclesiarum in quibus dominus rex habet regaliam ». En latin ; 14 « Le chapitre Dum episcopus, concernant les regales, et, en marge, des annotations escrites de la main de feu Mr le procureur general en la chambre des comptes, Me Guillaume Du Molinet, fort utiles pour lesdictes regales ». En latin ; 15 « Valor decimarum omnium provinciarum et diocesum regni » ; 16 « Les bailliages de France » ; 17 « Moien d'evaluer debtes du temps passé par cedules ou monoyes dudict temps passé au temps de present ou au temps qu'on voudra faire l'evaluement du temps advenir » ; 18 Valeur du marc et des monnaies d'argent, de 1289 à 1428. En latin ; 19 Valeur du marc et des monnaies d'or, de 1316 à 1388. En latin ; 20 à 32 Ordonnances concernant la chambre des comptes et les finances ; 20 à 27 Ordonnances de CHARLES VII, des 25 sept. et 26 nov. 1443, 10 fév. 1445, 26 nov. 1447, 23 déc. 1454, 30 janvier 1456, 21 avr. 1460 ; 28 à 30 Ordonnances de LOUIS XII, des 19 nov. 1498, 5 fév. 1499, 20 déc. 1506 ; 31 et 32 Ordonnances de FRANÇOIS Ier, de déc. 1520 et 28 décembre 1523 ; 33 à 38 Instructions ; 33 « Les instructions pieça aictes par le conseil du roy sur les finances que l'on peult raisonnablement demander pour le roy auxgens d'eglise, pour le temps passé qu'ilz ont tenu possessions sans l'asentement du roy, lesquelles ont esté doublées, pour, selon icelles, obtenir les finances deues au roy nostre sire, à cause des possessions que iceulx gens d'eglise tiennent non admortiez sans l'assentement du roy nostre dit seigneur » ; 34 « Instructions royaulx sur le faict des fiefz et arriere fiefz et choses nobles acquises par non nobles » ; 35 « Autres instructions pour recouvrer les ventes, quintz, deniers, rachaptz, reliefz, et autres droictz, touchant le domaine du roy » ; 36 « Instructions sur la maniere de lever le droict de tiers et danger » ; 37 « Instructions sur la maniere de bailler les fermes du dommaine du roy nostre sire, tant à ung comme à deux ou trois ans, ou plus ou moings » ; 38 « Ordonnance sur la maniere de bailler lesdictes fermes, faicte par le roy CHARLES VI,... Paris, 2 janvier 1398 » ; 39 à 42 Recueil de documents concernant la chambre des comptes ; 39 « Reglement prononcé aux procureurs de la chambre » ; 40 « Autre reglement concernant les proffictz de fiefz » ; 41 « Arrestz de la chambre sur l'adresse des lettres de serment de fidelité des evesques, qu'elle doibt estre faicte à la dicte chambre seullement et non à la court de parlement » ; 42 « Reglement entre les clercz du roy en la chambre des comptes, d'une part, et les greffiers d'icelle, d'autre » ; 43 « Touchant les grenetiers » ; 44 « Des aubeynes, espaves, estrayers » ; 45 à 50 « Droits des clers du roi en la chambre des comptes » ; 45 « Les droictz feodaux appartenans à messeigneurs les clerz du roy en la chambre des comptes sur les receptes ordinaires de Champagne » ; 46 « Autres droictz qu'ilz ont en Poictou » ; 47 « Autres droictz qu'ilz prenent sur l'escurie du roy » ; 48 « Autres droictz qu'ils prenent sur les monoyes ; 49 « Accord par lesdictz clerz, touchant leurs droictz de Champagne » ; 50 « Estat des gaiges et droictz desdictz clerz, selon les cedules du Tresor, et les droictz de busche et de robbe » ; 51 « Privilleges et franchises de Mrs des comptes ». En latin ; 52 « Des stipes et nobis de Normandye » ; 53 « Le sciendum de la chancellerie, contenant les privileges des secretaires du roy, droictz de bourse et des chauffecire ». En latin ; 54 « Origo regum Francie » ; 55 « Du baptesme de M. le dauphin, filz du roy Charles VIII » ; 56 « De frere François de Paule, natif de Calabre » ; 57 « Lignée du roy Jehan » ; 58 à 60 Ordonnances ; 58 Ordonnance de LOUIS XII, « que tous comptables compteront en la chambre des comptes... Bloys, le 24 novembre 1511 » ; 59 Ordonnance de PHILIPPE VI, roi de France, touchant les foires de Champaigne et Brie... 1349 » ; 60 « Ordonnance » de « FRANÇOIS [Ier] sur le fait du domaine... Fontainebleau, le 30 may 1539 » ; 61 « Anoblissement de Jacques Le Lieur » par le roi Charles VII. « Datum Parisius, anno Domini millesimo trecentesimo sexagesimo, mense maii ». En latin ; 62 et 63 Chambre des comptes ; 62 « Droictz de Mrs des comptes » ; 63 « De l'authorité et jurisdiction de la chambre »
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Recent dose-response sleep restriction studies, in which nightly sleep is curtailed to varying degrees (e.g., 3-, 5-, 7-hours), have found cumulative, dose-dependent changes in sleepiness, mood, and reaction time. However, brain activity has typically not been measured, and attentionbased tests employed tend to be simple (e.g., reaction time). One task addressing the behavioural and electrophysiological aspects of a specific attention mechanism is the Attentional Blink (AB), which shows that the report accuracy of a second target (T2) is impaired when it is presented soon after a first target (Tl). The aim of the present study was to examine behavioural and electrophysioiogical responses to the AB task to elucidate how sleep restriction impacts attentional capacity. Thirty-six young-adults spent four consecutive days and nights in a sleep laboratory where sleep, food, and activity were controlled. Nightly sleep began with a baseline sleep (8 hours), followed by two nights of sleep restriction (3,5 or 8 hours of sleep), and a recovery sleep (8 hours). An AB task was administered each day at 11 am. Results from a basic battery oftests (e.g., sleepiness, mood, reaction time) confirmed the effectiveness of the sleep restriction manipulation. In terms of the AB, baseline performance was typical (Le., T2 accuracy impaired when presented soon after Tl); however, no changes in any AB behavioural measures were observed following sleep restriction for the 3- or 5-hour groups. The only statistically significant electrophysiological result was a decrease in P300 amplitude (for Tl) from baseline to the second sleep restriction night for the 3-hour group. Therefore, following a brief, two night sleep restriction paradigm, brain functioning was impaired for the TI of the AB in the absence of behavioural deficit. Study limitations and future directions are discussed.
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The neuropeptide Th1RFamide with the sequence Phe-Met-Arg-Phe-amide was originally isolated in the clam Macrocallista nimbosa (price and Greenberg, 1977). Since its discovery, a large family ofFl\1RFamide-related peptides termed FaRPs have been found to be present in all major animal phyla with functions ranging from modulation of neuronal activity to alteration of muscular contractions. However, little is known about the genetics encoding these peptides, especially in invertebrates. As FaRP-encoding genes have yet to be investigated in the invertebrate Malacostracean subphylum, the isolation and characterization ofFaRP-encoding DNA and mRNA was pursued in this project. The immediate aims of this thesis were: (1) to amplify mRNA sequences of Procambarus clarkii using a degenerate oligonucleotide primer deduced from the common amino acid sequence ofisolated Procambarus FaRPS, (2) to determine if these amplification products encode FaRP gene sequences, and (3) to create a selective cDNA library of sequences recognized by the degenerate oligonucleotide primer. The polymerase chain reaction - rapid amplification of cDNA ends (PCR-RACE) is a procedure in which a single gene-specific primer is used in conjunction with a generalized 3' or 5' primer to amplify copies ofthe region between a single point in the transcript and the 3' or 5' end of cDNA of interest (Frohman et aI., 1988). PCRRACE reactions were optimized with respect to primers used, buffer composition, cycle number, nature ofgenetic substrate to be amplified, annealing, extension and denaturation temperatures and times, and use of reamplification procedures. Amplification products were cloned into plasmid vectors and recombinant products were isolated, as were the recombinant plaques formed in the selective cDNA library. Labeled amplification products were hybridized to recombinant bacteriophage to determine ligated amplification product presence. When sequenced, the five isolated PCR-RACE amplification products were determined not to possess FaRP-encoding sequences. The 200bp, 450bp, and 1500bp sequences showed homology to the Caenorhabditis elegans cosmid K09A11, which encodes for cytochrome P450; transfer-RNA; transposase; and tRNA-Tyr, while the 500bp and 750bp sequences showed homology with the complete genome of the Vaccinia virus. Under the employed amplification conditions the degenerate oligonucleotide primer was observed to bind to and to amplify sequences with either 9 or 10bp of 17bp identity. The selective cDNA library was obselVed to be of extremely low titre. When library titre was increased, white. plaques were isolated. Amplification analysis of eight isolated Agt11 sequences from these plaques indicated an absence of an insertion sequence. The degenerate 17 base oligonucleotide primer synthesized from the common amino acid sequence ofisolated Procambarus FaRPs was thus determined to be non-specific in its binding under the conditions required for its use, and to be insufficient for the isolation and identification ofFaRP-encoding sequences. A more specific primer oflonger sequence, lower degeneracy, and higher melting temperature (TJ is recommended for further investigation into the FaRP-encoding genes of Procambarlls clarkii.
Resumo:
Letter to Burrell, McEwen and Co. from [S.D. Woodruff] regarding payments made to them, Jan.5, 1877.