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1.
Sustain Sci ; 17(3): 1009-1021, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35069918

RESUMO

Sustainability transition research seeks to understand the patterns and dynamics of structural societal change as well as unearth strategies for governance. However, existing frameworks emphasize innovation and build-up over exnovation and break-down. This limits their potential in making sense of the turbulent and chaotic dynamics of current transition-in-the-making. Addressing this gap, our paper elaborates on the development and use of the X-curve framework. The X-curve provides a simplified depiction of transitions that explicitly captures the patterns of build-up, breakdown, and their interactions. Using three cases, we illustrate the X-curve's main strength as a framework that can support groups of people to develop a shared understanding of the dynamics in transitions-in-the-making. This helps them reflect upon their roles, potential influence, and the needed capacities for desired transitions. We discuss some challenges in using the X-curve framework, such as participants' grasp of 'chaos', and provide suggestions on how to address these challenges and strengthen the frameworks' ability to support understanding and navigation of transition dynamics. We conclude by summarizing its main strength and invite the reader to use it, reflect on it, build on it, and judge its value for action research on sustainability transitions themselves. Supplementary Information: The online version contains supplementary material available at 10.1007/s11625-021-01084-w.

2.
IEEE Trans Biomed Eng ; 61(12): 2840-7, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24967979

RESUMO

Sleepiness and fatigue can reach particularly high levels during long-haul overnight flights. Under these conditions, voluntary or even involuntary sleep periods may occur, increasing the risk of accidents. The aim of this study was to assess the performance of an in-flight automatic detection system of low-vigilance states using a single electroencephalogram channel. Fourteen healthy pilots voluntarily wore a miniaturized brain electrical activity recording device during long-haul flights ( 10 ±2.0 h, Atlantic 2 and Falcon 50 M, French naval aviation). No subject was disturbed by the equipment. Seven pilots experienced at least a period of voluntary ( 26.8 ±8.0 min, n = 4) or involuntary sleep (N1 sleep stage, 26.6 ±18.7 s, n = 7) during the flight. Automatic classification (wake/sleep) by the algorithm was made for 10-s epochs (O1-M2 or C3-M2 channel), based on comparison of means to detect changes in α, ß, and θ relative power, or ratio [( α+θ)/ß], or fuzzy logic fusion (α, ß). Pertinence and prognostic of the algorithm were determined using epoch-by-epoch comparison with visual-scoring (two blinded readers, AASM rules). The best concordance between automatic detection and visual-scoring was observed within the O1-M2 channel, using the ratio [( α+θ )/ß] ( 98.3 ±4.1% of good detection, K = 0.94 ±0.07, with a 0.04 ±0.04 false positive rate and a 0.87 ±0.10 true positive rate). Our results confirm the efficiency of a miniaturized single electroencephalographic channel recording device, associated with an automatic detection algorithm, in order to detect low-vigilance states during real flights.


Assuntos
Acidentes Aeronáuticos/prevenção & controle , Viagem Aérea , Algoritmos , Nível de Alerta/fisiologia , Eletroencefalografia/métodos , Fases do Sono/fisiologia , Análise e Desempenho de Tarefas , Adulto , Inteligência Artificial , Feminino , Humanos , Masculino , Reconhecimento Automatizado de Padrão/métodos , Valores de Referência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
3.
Cytokine ; 56(2): 318-24, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21737301

RESUMO

Total sleep deprivation in humans is associated with increased daytime sleepiness, decreased performance, elevations in inflammatory cytokines, and hormonal/metabolic disturbances. To assess the effects of 40 h of total sleep deprivation (TSD) under constant and well controlled conditions, on plasma levels of TNF-α and its receptor (TNFR1), interleukin-6 (IL-6), cortisol and C-reactive protein (CRP), sleepiness and performance, 12 healthy men (29±3 years) participated in a 5-days sleep deprivation experiment (two control nights followed by a night of sleep loss and one recovery night). Between 0800 and 2300 (i.e. between 25 and 40 h of sleep deprivation), a serial of blood sampling, multiple sleep latency, subjective levels of sleepiness and reaction time tests were completed before (day 2: D2) and after (day 4: D4) one night of sleep loss. We showed that an acute sleep deprivation (i.e. after 34 and 37 h of sleep deprivation) induced a significant increase in TNF-α (P<0.01), but there were no significant changes in TNFR1, IL-6, cortisol and CRP. In conclusion, our study in which constant and controlled experimental conditions were realized with healthy subjects and in absence of psychological or physical stressors, an acute total sleep deprivation (from 34 h) was sufficient to induce secretion of pro-inflammatory cytokine such as TNF-α, a marker more described in chronic sleep restriction or deprivation and as mediators of excessive sleepiness in humans in pathological conditions.


Assuntos
Privação do Sono/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Adulto , Proteína C-Reativa/metabolismo , Humanos , Hidrocortisona/sangue , Interleucina-6/sangue , Masculino , Desempenho Psicomotor , Fator de Necrose Tumoral alfa/sangue
4.
Horm Metab Res ; 42(1): 31-7, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19821225

RESUMO

This study investigated effects of a high protein (PROT) versus a high carbohydrate (CHO) diet on performance and physiological responses during an ultraendurance climbing race at moderate altitude. On two different periods, in a randomised crossover design, ten climbers (30.0+/-0.9 years) participated in the race (duration 29 h approximately, energy expenditure 43.6+/-1.2 MJ.day (-1)) and were fed either with the PROT (30% protein content) or the CHO diet (68% carbohydrate) each providing 16.74 MJ. Mental performance was assessed by the Stroop test and we estimated maximal voluntary strength of quadriceps muscle. We quantified metabolic and hormonal circulating concentrations. Mental performance was unaffected after the two races, while muscular performance and body weight were decreased (both p<0.01) with no diet effects. Decreases were measured for IGF-I concentration and its binding protein IGFBP-3 (p<0.001), and increases for cortisol and norepinephrine (p<0.01) with no diet effects. Glucose concentration decreased (p<0.05) without diet effects, while amino acids (leucine, isoleucine, valine, and tyrosine) decreased in CHO group (p<0.001). Leptin concentration decreased (p<0.001) without diet effects, whereas total ghrelin increased in CHO group (p<0.01). Our results showed that a high PROT or high CHO intake during physical exertion at moderate altitude maintained mental performance, but did not limit muscle force reduction and body weight loss. There was decreased glucose availability, and hormonal responses indicated both catabolism and extreme energy deficiency induced by exercise with opposite responses of ghrelin and leptin. The ghrelin response was additionally indicative of macronutrient intake during the race.


Assuntos
Carboidratos da Dieta/metabolismo , Proteínas Alimentares/metabolismo , Montanhismo/fisiologia , Resistência Física , Adulto , Altitude , Carboidratos da Dieta/administração & dosagem , Proteínas Alimentares/administração & dosagem , Proteínas Alimentares/sangue , Metabolismo Energético , Humanos , Insulina/sangue , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/sangue , Fator de Crescimento Insulin-Like I/metabolismo , Masculino
5.
J Appl Physiol (1985) ; 96(1): 50-8, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12959951

RESUMO

We measured the effects of slow-release caffeine (SRC) and melatonin (Mlt) on sleep and daytime sleepiness after a seven-time zone eastbound flight. In a double-blind, randomized, placebo-controlled study, each of three groups of nine subjects was given either 300 mg SRC on recovery day 1 (D1) to D5 (0800) or 5 mg Mlt on preflight D-1 (1700), flight day D0 (1600), and from D1 to D3 (2300), or placebo (Pbo) at the same times. Nighttime sleep was evaluated by polysomnography and daytime sleepiness from measurements of sleep latencies and continuous wrist actigraphy. Compared with baseline, we found a significant rebound of slow-wave sleep on night 1 (N1) to N2 under Pbo and Mlt and a significant decrease in rapid eye movement sleep on N1 (Pbo) and N1-N3 (Mlt). Sleepiness was objectively increased under Pbo (D1-D6) and Mlt (D1-D3). SRC reduced sleepiness but also tended to affect sleep quality until the last drug day. In conclusion, both drugs have positive effects on some jet lag symptoms after an eastbound flight: SRC on daytime sleepiness, and Mlt on sleep.


Assuntos
Anticonvulsivantes/administração & dosagem , Cafeína/administração & dosagem , Estimulantes do Sistema Nervoso Central/administração & dosagem , Síndrome do Jet Lag/tratamento farmacológico , Melatonina/administração & dosagem , Adulto , Temperatura Corporal , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sono/efeitos dos fármacos , Fases do Sono/efeitos dos fármacos
6.
Rev Sci Tech ; 20(2): 379-84, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11548514

RESUMO

The use of a measure incorporating traceability that directly or indirectly affects international trade is permitted under the World Trade Organization Agreement on the Application of Sanitary and Phytosanitary Measures, provided that the measure is applied in accordance with the provisions of the Agreement. These provisions state that the measure must be necessary, scientifically justified, no more trade restrictive than required and consistent with the appropriate level of protection of the importing country. If requested, importing countries are required to assess claims by exporting countries regarding an alternative measure(s) providing an equivalent level of protection or with regard to regionalisation.


Assuntos
Sistemas de Identificação Animal/veterinária , Comércio/normas , Saneamento/normas , Sistemas de Identificação Animal/métodos , Animais , Comércio/legislação & jurisprudência , Política de Saúde , Humanos , Agências Internacionais , Cooperação Internacional , Carne/normas , Produtos da Carne/normas , Saneamento/métodos
7.
Neurosci Lett ; 305(2): 99-102, 2001 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-11376893

RESUMO

We investigated the influence of +Gz acceleration (head-to-foot inertial forces) onset on cerebral cortical blood flow (CBF) of rhesus monkeys to study the mechanisms underlying +Gz-induced loss of consciousness (G-LOC). CBF was measured through a chronic cranial window by laser-Doppler flowmetry and electrodes in contact with the dura mater were used to detect G-LOC (suppression of the cortical electrical activity). The animals were centrifuged up to +12 Gz with different G-onset rate until G-LOC occurred. G-LOC was preceded by a 2-5 s decrease in CBF. At G-LOC detection, CBF was not related to G-onset rate (mean CBF change: -76 +/- 9% of control value). We conclude that G-LOC results from cerebral ischemia rather than from mechanical stresses applied to the brain.


Assuntos
Córtex Cerebral/irrigação sanguínea , Gravitação , Estresse Fisiológico/complicações , Inconsciência/etiologia , Inconsciência/fisiopatologia , Animais , Centrifugação , Fluxometria por Laser-Doppler , Macaca mulatta , Fluxo Sanguíneo Regional
8.
J Sleep Res ; 10(4): 265-76, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11903856

RESUMO

Some long work or shift work schedules necessitate an elevated and prolonged level of vigilance and performance but often result in sleep deprivation (SD), fatigue and sleepiness, which may impair efficiency. This study investigated the effects of a slow-release caffeine [(SRC) at the daily dose of 600 mg] on vigilance and cognitive performance during a 64 h continuous wakefulness period. Sixteen healthy males volunteered for this double-blind, randomised, placebo controlled, two-way crossover study. A total of 300-mg SRC or placebo (PBO) was given twice a day at 21:00 and 9:00 h during the SD period. Vigilance was objectively assessed with continuous electroencephalogram (EEG), the multiple sleep latency tests (MSLT) and wrist actigraphy. Cognitive functions (information processing and working memory), selective and divided attention were determined with computerised tests from the AGARD-NATO STRES Battery (Standardised Tests for Research with Environmental Stressors). Attention was also assessed with a symbol cancellation task and a Stroop's test; alertness was appreciated from visual analogue scales (VAS). Tests were performed at the hypo (02:00-04:00 h, 14:00-16:00 h) and hypervigilance (10:00-12:00 h, 22:00-00:00 h) periods during SD. Central temperature was continuously measured and safety of treatment was assessed from repeated clinical examinations. Compared with PBO, MSLT showed that SRC subjects were more vigilant from the onset (P=0.001) to the end of SD (P < 0.0001) whereas some cognitive functions were improved till the thirty third of SD but others were ameliorated through all the SD period and alertness was better from the thirteenth hour of SD, as shown by Stroop's test (P=0.048). We showed that 300-mg SRC given twice daily during a 64-h SD is able to antagonize the impairment produced on vigilance and cognitive functions.


Assuntos
Nível de Alerta/efeitos dos fármacos , Cafeína/farmacologia , Estimulantes do Sistema Nervoso Central/farmacologia , Cognição/efeitos dos fármacos , Privação do Sono/induzido quimicamente , Vigília/efeitos dos fármacos , Adulto , Temperatura Corporal/fisiologia , Cafeína/administração & dosagem , Cafeína/efeitos adversos , Estimulantes do Sistema Nervoso Central/administração & dosagem , Estimulantes do Sistema Nervoso Central/efeitos adversos , Estudos Cross-Over , Preparações de Ação Retardada , Método Duplo-Cego , Humanos , Masculino , Fatores de Tempo
9.
J Appl Microbiol ; 86(2): 353-8, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10063635

RESUMO

Pure cultures of three species of bifidobacteria (Bifidobacterium longum, Bif. adolescentis and Bif. bifidum), Lactobacillus acidophilus and a mixed culture of Lact. delbrueckii subsp. bulgaricus and Streptococcus salivarius subsp. thermophilus were each enumerated on two differential media and six selective media for the enumeration of bifidobacteria. The appearance of the colonies on the differential media was as expected but when mixed cultures were present, it proved extremely difficult to distinguish one species from another. Of the selective media, AMC, RMS, NPNL and BL-OG performed well in that they gave good recoveries of bifidobacteria and were inhibitory to the growth of Lact. delbrueckii subsp. bulgaricus, Strep. salivarius subsp. thermophilus and Lact. acidophilus. However, of these four media, AMC was most convenient as it is based on a commercially available medium, whereas the others must be made up from individual constituents. The AMC agar is thus a good choice for the routine enumeration of bifidobacteria from mixed cultures.


Assuntos
Bifidobacterium/crescimento & desenvolvimento , Contagem de Colônia Microbiana/métodos , Meios de Cultura , Leite/microbiologia , Iogurte/microbiologia , Animais , Estudos de Avaliação como Assunto , Lactobacillus/crescimento & desenvolvimento , Lactobacillus acidophilus/crescimento & desenvolvimento , Streptococcus/crescimento & desenvolvimento
10.
Electroencephalogr Clin Neurophysiol ; 106(3): 206-12, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9743278

RESUMO

Extensive work on sleep-wake cycles in non-human primates has been carried out using conventional EEG scoring. In this study, simultaneous somnopolygrams and video recordings at 1 frame/s were performed on 6 adult rhesus monkeys (Macaca mulatta) during a 24 h period. Wakefulness, NREM sleep and REM sleep were scored by analysis of animal behavior from video data, using characteristic criteria for each state of vigilance. Results were then compared with those of conventional EEG scoring. Values of the total amount for each state obtained by the two scoring methods during the light and the dark periods were significantly closely related (P < 0.001) with a high correlation coefficient for wakefulness (r1 = 0.99956), for NREM sleep (r1 = 0.99641) and for REM sleep (r1 = 0.98708). Moreover, the epoch by epoch analysis between both methods showed a high concordance with percent agreement values of 95.68% for wakefulness, 93.52% for NREM sleep and 94.02% for REM sleep. The number of REM sleep episodes was similarly defined. The patterns of successive sleep-wake cycles determined from both scorings were superimposable, as were the frequent state changes for the same time segments. The video method's main limitation was that the 4 stages of NREM sleep could not be differentiated. Reliability and advantages of sleep-wake scoring by behavioral analysis are discussed. These results suggest that the video methodology is relevant as a non-invasive technique complementary to conventional EEG analysis for sleep studies in rhesus monkeys.


Assuntos
Comportamento Animal/fisiologia , Sono/fisiologia , Vigília/fisiologia , Animais , Escuridão , Eletroencefalografia/métodos , Luz , Macaca mulatta , Masculino , Polissonografia , Fases do Sono/fisiologia , Gravação em Vídeo
11.
Rev Sci Tech ; 15(2): 659-73, 1996 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8890386

RESUMO

Australia is free from many significant diseases of aquatic animals. Quarantine policies for aquatic animals and aquatic animal products are designed to meet the international trade obligations of Australia, while preventing the entry of pests and diseases. These policies are supported by measures to prevent the introduction of aquatic species which would have deleterious effects on the environment. The Australian approach to quarantine--utilising objective risk analysis, where possible--is more difficult to apply to aquatic species than to terrestrial animals, as it is hard to identify and quantify risks when much of the relevant disease and epidemiological information is unavailable. Other than ornamental fish, for which stringent quarantine restrictions apply, involving isolation in quarantine premises, there have been no commercial importations of live aquatic species into Australia over the past decade. The onerous requirements for detailed analysis of disease risks and environmental implications have tended to deter potential importers. For many years, specific controls--based on risk analysis--have also been placed on the importation of products such as oysters in the shell, salmonid products, and feeds and meals of aquatic animal origin. A major review of quarantine requirements has been commissioned.


Assuntos
Doenças dos Peixes/prevenção & controle , Legislação Veterinária , Quarentena , Frutos do Mar , Ração Animal/normas , Animais , Animais Domésticos , Austrália/epidemiologia , Crustáceos , Notificação de Doenças/legislação & jurisprudência , Doenças dos Peixes/epidemiologia , Pesqueiros/legislação & jurisprudência , Peixes , Cooperação Internacional , Legislação sobre Alimentos , Moluscos , Quarentena/legislação & jurisprudência
12.
Kidney Int ; 47(5): 1258-65, 1995 May.
Artigo em Inglês | MEDLINE | ID: mdl-7637255

RESUMO

DNA-containing immune complexes (IC) are believed to have a central causal role in the glomerulonephritis of systemic lupus erythematosus. Extracellular DNA which provides the antigenic source for these ICs circulates as oligonucleosomes (ON). The in vivo glomerular uptake of radiolabeled ON in rats, as well as its binding by cultured rat mesangial cells, was examined. The data show that the binding of ON to kidney, and specifically glomeruli, was almost fourfold greater than that of purified DNA. Uptake appeared dose-dependent and saturable, while there were no differences in hepatic or splenic uptake. Most of the nucleosomal DNA recovered from glomeruli was TCA-precipitable, and on gel electrophoresis was about 100 to 300 bp, a size sufficient to allow formation of large ICs. In vitro studies demonstrated that ON are bound by cultured mesangial cells in a dose-dependent and saturable manner, with a dissociation constant of 1.25 x 10(-10) M/liter and 750 binding sites per cell. Autoradiography of cell cultures incubated with radiolabeled ON showed deposition along the plasma membrane which was inhibited by excess unlabeled ON. The data show that binding of ON to glomeruli exceeds that of purified DNA and may be mediated by histones. ON bind to mesangial cells in a receptor-mediated fashion. The data support the hypothesis of in situ formation of DNA-containing ICs and suggest a role for the mesangial cell in lupus glomerulonephritis.


Assuntos
Mesângio Glomerular/metabolismo , Nucleossomos/metabolismo , Receptores de Superfície Celular/metabolismo , Animais , Autorradiografia , Células Cultivadas , DNA/metabolismo , Eletroforese em Gel de Poliacrilamida , Mesângio Glomerular/citologia , Masculino , Perfusão , Radioisótopos de Fósforo , Ratos , Ratos Sprague-Dawley
13.
Fundam Clin Pharmacol ; 9(3): 271-9, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-7557823

RESUMO

Modafinil, a new psychostimulant, was evaluated in eight healthy volunteers subjected to 60 hours of sleep deprivation. During continued wakefulness, vigilance was evaluated by self-assessment questionnaires, analogue visual scales, multiple sleep latency tests (MSLT), sleep logs, and continuous ambulatory electroencephalographic recordings (EEG). Modafinil (200 mg) or a placebo was given every 8 hours for three days; the sessions were separated by a 15 day wash out period. Results indicated a satisfactory level of vigilance, both subjective and objective, after the administration of modafinil, characterised by the quasi total absence of microsleep episodes which gradually occurred under placebo conditions. The confirmed wakening potency of modafinil makes this substance suitable for therapeutic use in patients with sleep disorders such as Gelineau's syndrome and hypersomnia.


Assuntos
Compostos Benzidrílicos/farmacologia , Estimulantes do Sistema Nervoso Central/farmacologia , Desempenho Psicomotor/efeitos dos fármacos , Privação do Sono/fisiologia , Adulto , Eletroencefalografia/efeitos dos fármacos , Humanos , Masculino , Modafinila , Sono/efeitos dos fármacos
14.
Rev Sci Tech ; 12(4): 1147-51, 1993 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8312616

RESUMO

The authors discuss the risk assessment currently being conducted by the Australian Quarantine and Inspection Service (AQIS) on the importation of salmon products. AQIS conducted a public consultation on the proposal, in line with Australian Government policy on transparency and accountability in the quarantine decision-making process. The authors examine the factors which should be taken into account in the assessment of the risk associated with the importation of such products, and note the difficulties encountered with the epidemiology of fish diseases.


Assuntos
Doenças dos Peixes/prevenção & controle , Microbiologia de Alimentos , Salmão/microbiologia , Animais , Austrália , Comércio , Doenças dos Peixes/epidemiologia , Manipulação de Alimentos/normas , Modelos Biológicos , Prevalência , Fatores de Risco
15.
Aust Vet J ; 67(6): 215-8, 1990 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2222365

RESUMO

Three shipments of sheep being exported live by sea were examined to determine their thiamine status. Measurements were made of thiamine concentration in liver and ruminal contents, transketolase activity in erythrocytes and thiaminase activity in ruminal liquor. Sheep that died or were clinically ill and euthanased had significantly lower hepatic and ruminal thiamine concentrations than clinically healthy control sheep. A high proportion had thiamine concentrations comparable to those found in sheep that die with polioencephalomalacia. Thiamine concentrations decreased with increasing time that sheep were in pre-embarkation feedlots and on board ship. Destruction of thiamine in the rumen by thiaminase was not a significant factor. Erythrocyte transketolase activities indicated that many of the sheep that arrived in the Middle East without signs of clinical disease were also in a state of thiamine insufficiency.


Assuntos
Doenças dos Ovinos/diagnóstico , Deficiência de Tiamina/veterinária , Animais , Eritrócitos/enzimologia , Hidrolases/análise , Fígado/química , Análise de Regressão , Rúmen/química , Rúmen/enzimologia , Ovinos , Navios , Tiamina/análise , Deficiência de Tiamina/diagnóstico , Transcetolase/sangue , Meios de Transporte
16.
Int J Gynaecol Obstet ; 23(6): 481-8, 1985 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-2868943

RESUMO

This prospective study was undertaken to examine the reliability of fluorescence polarization (FP) readings on amniotic fluid collected from the posterior fornix of the vagina after membranes have ruptured. This method was chosen because it is as accurate as the L/S ratio, but it is simpler, faster and requires only 0.5 ml of sample. Forty-seven out of 55 patients were eligible for the study, for a success rate of 85%. Respiratory distress syndrome (RDS) occurred in one out of 29 neonates with FP in the mature or low risk group. In the high risk group for RDS, 7 out of 12 developed the syndrome. In 11 patients, FP-values obtained from transabdominal amniocentesis were not significantly different from those obtained from pooled vagina amniotic fluid once membranes were ruptured. Analysis of pooled vaginal amniotic fluid is simple, non-invasive and capable of being performed with a high rate of success. FP-values from properly collected pooled vaginal amniotic fluid can be used in the assessment of functional fetal lung maturity.


Assuntos
Líquido Amniótico/análise , Ruptura Prematura de Membranas Fetais , Pulmão/embriologia , Amniocentese , Feminino , Maturidade dos Órgãos Fetais , Polarização de Fluorescência , Humanos , Recém-Nascido , Gravidez , Estudos Prospectivos , Síndrome do Desconforto Respiratório do Recém-Nascido/diagnóstico , Risco
17.
Psychosom Med ; 46(3): 239-54, 1984.
Artigo em Inglês | MEDLINE | ID: mdl-6739684

RESUMO

Studies of pituitary-gonadal function in men with erectile disorders have provided conflicting findings. This study compares blood LH and testosterone during sleep in 17 physically healthy men with erectile impotence and 12 matched normal controls, and relates hormonal variations to stages of sleep and penile tumescence. Subjects, aged 23-36 were studied in a sleep laboratory for 3-6 nights with the last two nights devoted to sequential blood sampling every 20 minutes. Five men had never been able to achieve intercourse (primary impotent group) and 12 suffered from a life-long history of intermittent erectile failures (secondary-impotent group). There were no significant differences in sleep duration and REM time among the impotent groups and normal controls. Primary-impotent men showed half as many full tumescent episodes as secondary-impotent men and controls, and spent significantly less time above 80% of full tumescence. The secondary-impotent group did not differ in nocturnal penile tumescent measures from controls. There was a pattern of irregularly occurring fluctuations in plasma LH and testosterone with no differences among groups in frequency and amount of peak hormonal increases. Normal subjects had significantly higher mean testosterone concentrations during REM sleep than during other sleep stages, and during full tumescence than during partial and nontumescent periods. A direct causal relation between REM-related activity and circulating testosterone was not supported by the observation that the hormonal levels during REM sleep and during full tumescence did not differ statistically from the levels measured during adjacent time periods. As with normal subjects, the secondary-impotent group exhibited higher testosterone levels during REM sleep and full tumescence; by contrast, the primary-impotent group did not show significant hormonal differences across stages of sleep and tumescent/ nontumescent periods. These data are discussed with respect to the possible existence of subgroups of impotent men without known organic pathology than may be characterized by psychophysiologic and endocrine differences during sleep.


Assuntos
Disfunção Erétil/sangue , Hormônio Luteinizante/sangue , Fases do Sono/fisiologia , Testosterona/sangue , Adulto , Nível de Alerta/fisiologia , Humanos , Masculino , Sono REM/fisiologia
18.
Clin Chem ; 29(11): 1951-4, 1983 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-6627632

RESUMO

Many currently used thin-layer chromatographic methods for phospholipid assay rely on charring the developed plate in the presence of cupric acetate. Saturated acyl phospholipids do not react. We find that substitution of cupric sulfate results in detection of both saturated and unsaturated phospholipids. By exploiting the difference with the two reagents, one can separately estimate the amounts of saturated phospholipid. The method described here is reproducible, and we illustrate its use in determinations of (3-sn-phosphatidyl)cholines (lecithins) in amniotic fluid from problem pregnancies.


Assuntos
Líquido Amniótico/análise , Doenças Fetais/metabolismo , Compostos Organometálicos , Fosfatidilcolinas/análise , Cromatografia em Camada Fina , Cobre , Sulfato de Cobre , Feminino , Idade Gestacional , Humanos , Recém-Nascido , Gravidez , Diagnóstico Pré-Natal , Síndrome do Desconforto Respiratório do Recém-Nascido/diagnóstico , Esfingomielinas/análise
19.
Arch Sex Behav ; 11(3): 189-200, 1982 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-6814402

RESUMO

Five physically healthy young males suffering from erectile impotence and five normal controls of similar age are the subjects of this preliminary report. All were studied in the sleep laboratory during 3 to 5 nights with the last two devoted to sequential hormonal sampling by means of an indwelling venous catheter. Electroencephalogram, eye movements, and penile tumescence were monitored continually through the night. Plasma LH, FSH, and testosterone were measured every 20 minutes by radioimmunoassay. There were no differences between the patients with erectile impotence and normal controls in all sleep parameters investigated, including mean tumescent time, time in simultaneous REM and tumescence, and number of full and partial tumescent episodes. Marked fluctuations in plasma LH, FSH, and testosterone were observed during sleep without differences noted between the two groups. Mean plasma LH, but not FSH or testosterone, was significantly lower in the impotent men. There were no significant differences in mean plasma gonadotrophins and testosterone between tumescent episodes and nontumescent periods in either group. A significant relation was found in normals, but not in the men with erectile dysfunction, between the occurrence of REM sleep and abrupt elevations in testosterone. Testosterone levels during REM sleep with tumescence were also consistently higher than during the condition of non-REM without tumescence in the normal, but not in the impotent, group.


Assuntos
Disfunção Erétil/sangue , Hormônio Foliculoestimulante/sangue , Hormônio Luteinizante/sangue , Sono/fisiologia , Testosterona/sangue , Adulto , Disfunção Erétil/fisiopatologia , Humanos , Masculino , Pênis/fisiopatologia , Sono REM/fisiologia
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