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4.
J Biomed Phys Eng ; 8(4): 375-380, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30568927

RESUMO

BACKGROUND: It has been shown that short-wavelength blue component of the visible light spectrum can alter the circadian rhythm and suppress the level of melatonin hormone. The short-wavelength light emitted by smartphones' screens can affect the sleep quality of the people who use these devices at night through suppression of melatonin. OBJECTIVES: In this study, we examined the effects of covering the screens of smartphones with different filters (changing the effective wavelength of the light) on sleep delay time in 43 healthy students. MATERIALS AND METHODS: Volunteer students were asked to go to bed at 23:00 and to use their mobile phones in bed for watching a natural life documentary movie for 60 minutes. No filter was used for one night while amber and blue filters were used for other 2 nights. Photospectrometry method was used to determine the output spectrum of the light passing through the filters used for covering the screens of the mobile phones. The order for utilizing amber or blue filters or using no filter was selected randomly. After 1 hour, the participants were asked to record their sleep delay time measured by a modified form of sleep time record sheet. RESULTS: The mean sleep delay time for the "no-filter" night was 20.84±9.15 minutes, while the sleep delay times for the nights with amber and blue filters were 15.26±1.04 and 26.33±1.59 minutes, respectively. CONCLUSION: The findings obtained in this study support this hypothesis that blue light possibly suppresses the secretion of melatonin more than the longer wavelengths of the visible light spectrum. Using amber filter in this study significantly improved the sleep quality. Altogether, these findings lead us to this conclusion that blocking the short-wavelength component of the light emitted by smartphones' screens improves human sleep.

5.
J Med Case Rep ; 10: 28, 2016 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-26837306

RESUMO

BACKGROUND: Paralysis of the external popliteal sciatic nerve is a frequent pathological condition that occurs after trauma. However, etiologies other than trauma, such as tumors, are also possible. The sensory collaterals of the external popliteal sciatic nerve have a small territory of innervation at the knee, and tumors involving these nerves become symptomatic after compression of the motor nerves. We here describe the first reported case of this phenomenon. CASE PRESENTATION: This case involved a lesion compressing the origin of the external popliteal sciatic nerve of a 13-year-old Moroccan boy diagnosed with a neurofibroma. He developed functional impairment of his left lower limb during a football game, and examination revealed a steppage gait. The initial diagnosis was stretching of the peroneal nerve. The definitive diagnosis of a neurofibroma was revealed by imaging and confirmed by surgery and pathology. Treatment involved total removal of the tumor; however, our patient's steppage gait persisted. CONCLUSIONS: Our patient developed compression of the external popliteal sciatic nerve from a tumor growing on a collateral nerve. Early diagnosis is an absolute necessity in such cases. Trauma and tumors of sensory nerves can distort the diagnosis, as in this case. Ultrasound and magnetic resonance imaging can contribute to an accurate diagnosis in patients with neuropathy in the absence trauma or tomacula.


Assuntos
Síndromes de Compressão Nervosa/etiologia , Neurofibroma/complicações , Neoplasias do Sistema Nervoso Periférico/complicações , Nervo Fibular , Adolescente , Humanos , Masculino , Neurofibroma/diagnóstico , Neoplasias do Sistema Nervoso Periférico/diagnóstico
7.
Rev Med Brux ; 34(2): 87-9, 2013.
Artigo em Francês | MEDLINE | ID: mdl-23755715

RESUMO

Rapid in clinic measurement of glycated hemoglogin (HbA1c) allows to determine the level of metabolic control within a few minutes on capillary blood. We have evaluated the new DCA Vantage (Siemens) based on an immunological technique, replacing the DCA 2000+ (Siemens). The study included 120 unselected young type 1 diabetic patients, with different degrees of metabolic control. The DCA Vantage was compared with the HPLC system (Menarini HA 8160) whose deviation from the DCCT was < 0.1% across the clinical range. The mean underestimation of the DCA Vantage was -0.40%. The agreement limits (+/- 1.96 SD) were between 0.14% and -0.93%; this means +/- 0.53% around -0.40%. In conclusion, the DCA Vantage underestimates HbA1c levels; however it met the acceptance criteria of having a coefficient of variation < 3%.


Assuntos
Diabetes Mellitus Tipo 1/sangue , Hemoglobinas Glicadas/análise , Adolescente , Análise Química do Sangue/métodos , Capilares , Criança , Humanos , Fatores de Tempo
8.
J Hum Nutr Diet ; 26 Suppl 1: 97-104, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23679071

RESUMO

BACKGROUND: The present study aimed to assess the effects of Ramadan intermittent fasting on body weight and composition and the effects of age and sex. METHODS: Body weight, height, waist and hip circumferences were measured, body mass index (BMI) was calculated and fat mass, fat-free mass and percentage body fat were assessed by bioelectrical impedance on 240 adult subjects (male: 158) who fasted between sunrise and sunset for at least 20 days. Measurements were taken 1 week before and 1 week after Ramadan. Energy and macronutrient intakes were assessed using a 3-day food frequency questionnaire on a sub-sample of subjects before and during Ramadan. RESULTS: Subjects were grouped according to age and sex: ≤35 years (n = 82, males: 31) and 36-70 years (n = 158, males: 127). There were significant reductions in weight and BMI (P < 0.001) in almost all subjects, with the biggest being in males ≤35 years [-2.2% (SE 2.2%), P < 0.001]. Waist and hip circumferences fell in most subjects, except females aged 36-70 years. Fat mass fell in most subjects, ranging from 2.3% to 4.3% from baseline, except in females aged 36-70 years who did not experience a significant change. Fat-free mass was significantly reduced in all subjects (P < 0.001), whereas percentage body fat was lower only in males by 2.5% (SE 3.2%) (P = 0.029) in those aged ≤35 years and by 1.1% (SE 1.5%) (P < 0.001) in those aged 36-70 years. Dietary intake was similar before and during Ramadan, except in males whose protein intake fell during Ramadan (P = 0.032). CONCLUSIONS: Ramadan fasting leads to weight loss and fat-free mass reductions. Body composition changes vary depending on age and sex.


Assuntos
Composição Corporal , Índice de Massa Corporal , Peso Corporal , Dieta , Ingestão de Energia , Jejum/fisiologia , Islamismo , Tecido Adiposo/metabolismo , Adulto , Idoso , Compartimentos de Líquidos Corporais/metabolismo , Inquéritos sobre Dietas , Proteínas Alimentares/administração & dosagem , Feminino , Quadril , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores Sexuais , Inquéritos e Questionários , Circunferência da Cintura
9.
Prog Urol ; 23(4): 244-8, 2013 Apr.
Artigo em Francês | MEDLINE | ID: mdl-23544981

RESUMO

OBJECTIVE: The objective was to translate and linguistically validate in classical Arabic; the French version of the Urinary Symptom Profile (USP), the scale adapted to vesico-sphincter disorders. PATIENTS AND METHODS: Prospective study of 30 patients suffering the vesico-sphincter disorders. The translation was obtained by the method: translation back-translation. Patients completed the final questionnaire on day 0 and day 15. The feasibility, acceptability, internal consistency using Cronbach's alpha and test-retest repeatability by the interclass correlation coefficient (ICC) with the confidence interval (CI) were studied. RESULT: The sample consisted of 30 subjects including 20 men (66.6%) and 10 women (33.3%). The mean age was 48±18, 14 years ranging from 25 to 70 years. The questionnaire was feasible and acceptable. The Cronbach's alpha of the three dimensions, urinary stress incontinence, overactive bladder and voiding difficulties was respectively 0.9880, 0.9774 and 0.9683, respectively; the ICC was 0.9762 (95% CI: 0.9307-0.9919), 0.9558 (CI 95%: 0.8738-0.9849) and 0.9385 (95% CI: 0.8274-0.9789). CONCLUSION: The Arabic version of the classic USP had excellent internal consistency and excellent repeatability enable a full assessment of all urinary disorders and their severity.


Assuntos
Disuria/diagnóstico , Inquéritos e Questionários , Bexiga Urinária Hiperativa/diagnóstico , Incontinência Urinária/diagnóstico , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Traduções
10.
Phys Chem Chem Phys ; 15(16): 5888-97, 2013 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-23486920

RESUMO

In this study, we report the synthesis and application of a FePt/CNTs nanocomposite as a highly sensitive sensor and novel amide ligand (9,10-dihydro-9,10-ethanoanthracene-11,12-dicarboximido)-4-ethylbenzene-1,2-diol as a mediator for the determination of glutathione (GSH), nicotinamide adenine dinucleotide (NADH) and tryptophan (Trp). The synthesized materials were characterized with different methods such as NMR, IR spectroscopy, TEM, XRD, FESEM, cyclic voltammetry, electrochemical impedance spectroscopy and square wave voltammetry (SWV). The modified electrode exhibited a potent and persistent electron mediating behavior followed by well-separated oxidation peaks of GSH, NADH and Trp. The peak currents were linearly dependent on GSH, NADH and Trp concentrations in the range of 0.08-220, 1.0-400 and 5.0-500 µmol L(-1), with detection limits of 0.05, 0.8 and 1.0 µmol L(-1), respectively. The modified electrode was used for the determination of these compounds in real samples.


Assuntos
Técnicas Eletroquímicas , Glutationa/análise , Nanopartículas Metálicas/química , NAD/análise , Nanotubos de Carbono/química , Triptofano/análise , Amidas/química , Eletrodos , Ferro/química , Ligantes , Oxirredução , Platina/química
11.
Int J Artif Organs ; 27(8): 691-8, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15478540

RESUMO

Attempts have been made in this study to prepare a homogeneous and stable coating of graphite on polyester vascular grafts (GPVG) using an electrophoresis method to evaluate thromboresistant and blood compatibility of GPVG in comparison to non-coated PVG and InterGard (collagen sealed PVG) as control. Lactate dehydrogenase (LDH) activity measurement was carried out on all PVG types to evaluate platelet adhesion. To examine tissue reaction GPVG and non-coated sheets of knitted polyester fabric were implanted simultaneously in the dorsal flank of rats subcutaneously. The GPVG, non-coated and control were implanted in descending aorta as end-to-end or end-to-side implantation substitution in 25 sheep for 4-60 weeks. Results showed that the graphite coating on polyester vascular grafts reduced the number of adherent platelets and prevent platelet activation and spreading on the surface in comparison with non-coated and control. Pathological investigation showed inflammatory reactions were totally resolved after 12 weeks and there was no difference in the tissue reaction between graphite coated, non-coated and control patches. All grafts remained patent and there was no significant difference in patency rate between these three types of PVG. We found that GPVG has no need for pre-clotting and it showed lower platelet aggregation, thinner capsule formation and lower calcification after 15 months. However, suturing of GPVG was more difficult in comparison with the other types.


Assuntos
Prótese Vascular , Materiais Revestidos Biocompatíveis/química , Grafite , Poliésteres , Animais , Aorta Torácica/patologia , Aorta Torácica/cirurgia , Plaquetas/citologia , Calcinose/patologia , Feminino , Fibrose , Técnicas In Vitro , L-Lactato Desidrogenase/metabolismo , Ativação Plaquetária , Adesividade Plaquetária , Ratos , Ovinos
12.
Artigo em Inglês | MEDLINE | ID: mdl-9272769

RESUMO

The present experiment was designed to study the importance of strength and muscle mass as factors limiting maximal oxygen uptake (VO2max) in wheelchair subjects. Thirteen paraplegic subjects [mean age 29.8 (8.7) years] were studied during continuous incremental exercises until exhaustion on an arm-cranking ergometer (AC), a wheelchair ergometer (WE) and motor-driven treadmill (TM). Lean arm volume (LAV) was estimated using an anthropometric method based upon the measurement of various circumferences of the arm and forearm. Maximal strength (MVF) was measured while pushing on the rim of the wheelchair for three positions of the hand on the rim (-30 degrees, 0 degrees and +30 degrees). The results indicate that paraplegic subjects reached a similar VO2max [1.23 (0.34) 1 x min(-1), 1.25 (0.38) 1 x min(-1), 1.22 (0.18) 1 x min(-1) for AC, TM and WE, respectively] and VO2max/body mass [19.7 (5.2) ml x min(-1) x kg(-1), 19.5 (6.14) ml x min(-1) x kg(-1), 19.18 (4.27) ml x min(-1) x kg(-1) for AC, TM and WE, respectively on the three ergometers. Maximal heart rate f((c) (max)) during the last minute of AC (173 (17) beats x min(-1)], TM [168 (14) beats x min(-1)], and WE [165 (16) beats x min(-1)], were correlated, but f((c) (max)) was significantly higher for AC than for TM (P < 0.03). There were significant correlations between MVF and LAV (P < 0.001) and between the MVF data obtained at different angles of the hand on the rim [311.9 (90.1) N, 313.2 (81.2) N, 257.1 (71) N, at -30 degrees, 0 degrees and +30 degrees, respectively]. There was no correlation between VO2max and LAV or MVF. The relatively low values of f((c) (max)) suggest that VO2max was, at least in part, limited by local aerobic factors instead of central cardiovascular factors. On the other hand, the lack of a significant correlation between VO2max and MVF or muscle mass was not in favour of muscle strength being the main factor limiting VO2max in our subjects.


Assuntos
Braço/fisiologia , Contração Muscular/fisiologia , Músculo Esquelético/fisiologia , Consumo de Oxigênio/fisiologia , Paraplegia/fisiopatologia , Adulto , Índice de Massa Corporal , Ergometria , Feminino , Humanos , Masculino , Cadeiras de Rodas
13.
J Microencapsul ; 13(5): 527-35, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8864990

RESUMO

The microencapsulation of drugs is gaining importance in many research activities. A common technique for preparing microcapsules is the solvent evaporation method which is simple but has a large number of reaction control parameters. This study reports the microcapsulation of allopurinol by the solvent evaporation method and the release of the drug from the microcapsules. The effect of concentration of poly(vinyl alcohol) (as a surfactant), molecular weight of ethyl cellulose and stirrer speed in the preparative method were studied. The effect of molecular weight of ethyl cellulose and particle size on drug release were also investigated. It has been found that the drug release is decreased with increasing molecular weight of polymer and increasing particle size.


Assuntos
Alopurinol/metabolismo , Composição de Medicamentos/métodos , Cápsulas/química , Cápsulas/metabolismo , Celulose/análogos & derivados , Celulose/metabolismo , Portadores de Fármacos/química , Portadores de Fármacos/metabolismo , Cinética , Microscopia Eletrônica de Varredura , Microesferas , Peso Molecular , Tamanho da Partícula , Álcool de Polivinil/farmacologia , Tensoativos/farmacologia
14.
Appl Ergon ; 26(2): 117-21, 1995 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15677008

RESUMO

The relationship between exhaustion time (t(lim)) and the work performed at the end of constant-power exercises can be described by a linear relationship (Wlim = a + b t(lim)) for work involving the whole body (eg cycling) or part of the body (eg knee extensions). The slope b in the equation is termed the critical power and has been proposed as an index of the capacity to perform work over a long period of time. The first objective of the present study was to compare the values of slopes b calculated from whole-body work of short duration, ie maximal and supra-maximal cycling exercises (slope b1), with the values calculated from the same work, the durations of which were between 3.5 and 35 min (slope b3), as in the protocols used by Scherrer and Monod (1960) for body-part work. Slope b1 was significantly higher than slope b3 in 10 subjects who performed 5 cycling exhausting exercises (60, 73, 86, 100 and 120% of maximal aerobic power (MAP) in watts). Exhaustion times corresponding to power outputs equivalent to b1 and b3 were equal to 29.0 +/- 19.1 min and 48.6 +/- 9.8 min respectively. Moreover, the exhaustion times at 60 and 73%,MAP were significantly correlated with slope b3 (expressed in %MAP) but not with slope b1. Consequently, slope b3 should be considered as the critical power instead of slope b1 as in some studies in the literature (Moritani et al, 1981). The second objective was to study the physiological significance of the critical power (slope b3) of whole-body work (cycling). The workload that corresponded to a lactate steady state was not significantly different from b3 (68.8 +/- 6.0 vs 68.7 +/- 6.3% MAP). Nevertheless, slope b3 represents a workload corresponding to a slight but significant drift of heart rate or oxygen uptake. These results probably explain why b3 is a power which can be maintained for a long time but not beyond about l h in an average subject.

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