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1.
Clin Neurophysiol ; 122(5): 958-65, 2011 May.
Article in English | MEDLINE | ID: mdl-20889373

ABSTRACT

OBJECTIVE: To determine whether sleepiness and its evolution over sustained wakefulness could be reversed by nasal continuous positive airway pressure (CPAP) therapy in patients with obstructive sleep apnea-hypopnea syndrome (OSAHS). METHODS: Twelve OSAHS patients underwent three 32-h sessions of study: one before CPAP therapy (T0), the second (T3) and the third (T6), respectively, after 3 and 6 months of therapy. Each session included one night of sleep followed by 24 h of sustained wakefulness, during which EEG recordings and subjective ratings were performed every hour. RESULTS: The waking EEG in treated OSAHS patients was partially improved after 3 months of CPAP and their subjective complaint of sleepiness was normalized after 6 months. Theta power (3.9-7.8 Hz) was decreased as well as its time course during the diurnal period but beta power (12.7-29.2 Hz) remained higher. CONCLUSIONS: CPAP partially reverses waking EEG abnormalities in OSAHS patients with reduced theta activity after 3 months and removes the subjective complaint of sleepiness after 6 months. Nevertheless, the persistence of increased beta activity in treated patients suggests that efforts to stay awake remain strong after CPAP treatment. SIGNIFICANCE: CPAP influences the EEG's time course over sustained wakefulness in a frequency-specific manner in OSAHS patients.


Subject(s)
Cerebral Cortex/physiopathology , Continuous Positive Airway Pressure , Sleep Apnea, Obstructive/therapy , Sleep/physiology , Wakefulness/physiology , Electroencephalography , Humans , Middle Aged , Sleep Apnea, Obstructive/physiopathology , Treatment Outcome
2.
Eur Respir J ; 32(3): 705-9, 2008 Sep.
Article in English | MEDLINE | ID: mdl-18757699

ABSTRACT

It is well known that most patients with obstructive sleep apnoea/hypopnoea syndrome (OSAHS) suffer sleepiness, although the underlying mechanisms of this relationship remain unclear. The present study examined the relationship between nocturnal variables and the subsequent waking electroencephalogram (EEG), in order to determine if sleepiness was related to OSAHS severity and due to sleep fragmentation or to nocturnal hypoxaemia. In total, 12 moderate-to-severe OSAHS patients underwent a total sleep night followed by a 24-h period of sustained wakefulness where the waking EEG was measured every hour. The results showed that alpha (7.9-12.6 Hz) and beta (12.7-29.2 Hz) activities were strongly related to OSAHS severity, mainly reflected by the apnoea index. Moreover, spectral power in most of the waking EEG components was significantly correlated with nocturnal hypoxaemia indices, namely alpha and beta activity when hypoxaemia becomes severe. However, no correlation was found between the waking EEG and sleep fragmentation parameters. In conclusion, the present results suggest that the difficulty in maintaining an optimal level of alertness, reflected by a higher activity in awake alpha and beta bands (7.9-29.2 Hz) in obstructive sleep apnoea/hypopnoea syndrome, was better explained by: 1) the apnoea as opposed to the hypopnoea index; and 2) nocturnal hypoxaemia as opposed to sleep fragmentation.


Subject(s)
Sleep Apnea, Obstructive/physiopathology , Sleep Apnea, Obstructive/psychology , Wakefulness/physiology , Adult , Cohort Studies , Electroencephalography , Humans , Hypoxia/etiology , Hypoxia/psychology , Male , Middle Aged , Polysomnography , Severity of Illness Index , Sleep Apnea, Obstructive/complications , Sleep Deprivation/etiology , Sleep Deprivation/psychology
3.
Accid Anal Prev ; 40(4): 1365-70, 2008 Jul.
Article in English | MEDLINE | ID: mdl-18606267

ABSTRACT

OBJECTIVES: Many studies have demonstrated that patients with Obstructive Sleep Apnea Syndrome (OSAS), a very common sleep-related breathing disorder, are usually impaired in their driving ability because of decreased sleep quality. However, most of the simulation procedures in laboratories are designed to create monotonic conditions with low traffic density, if any, thereby leading to a dramatic decrease in performance in OSAS patients because of the lack of stimulation. The aim of this study was therefore to evaluate driving abilities in OSAS patients involved in a driving simulation task with medium traffic density, in order to replicate as far as possible real world conditions. The behavioral and physiological attributes likely to predict driving performance in these patients were also investigated. METHODS: After a normal night of sleep, 12 OSAS patients and 8 healthy controls performed 6 driving sessions during a 24-h period of sustained wakefulness. Driving performances (speed, lateral position, distances...) were measured and correlated to sleep parameters and to a waking EEG recorded during the task. RESULTS: Compared to controls, patients showed difficulties in speed adjustment. However, they maintained longer inter-vehicle distances, including during overtaking. Their waking EEG, while driving, showed increased spectral power in theta (3.9-7.8Hz) but also in beta (12.7-29.2Hz) activity, alpha power (7.9-12.6Hz) being increased in both groups due to sustained wakefulness. Poor sleep indices were correlated to increased theta and beta activities, as well as to more cautious behavior. DISCUSSION: In medium traffic density conditions, driving performance in OSAS patients remained at near normal levels, but with more cautious behavior than controls. This could be the result of a bigger effort to stay awake, as suggested by an increased beta activity in these patients.


Subject(s)
Automobile Driving , Sleep Apnea, Obstructive/psychology , Adult , Case-Control Studies , Electroencephalography , Female , Humans , Male , Middle Aged , Polysomnography , Predictive Value of Tests , Reaction Time/physiology , Sleep Apnea, Obstructive/physiopathology , Task Performance and Analysis , Wakefulness/physiology
4.
J Parasitol ; 94(1): 68-71, 2008 Feb.
Article in English | MEDLINE | ID: mdl-18372623

ABSTRACT

The prevalence of Toxoplasma gondii in free-ranging chickens (Gallus domesticus) is a good indicator of the prevalence of the parasite's oocysts in soil because chicken feed from the ground. The prevalence of T. gondii in free-range chickens from Ghana, Indonesia, Italy, Poland, and Vietnam was determined using the modified agglutination test (MAT). Antibodies to T. gondii were found in 41 (64%) of 64 chickens from Ghana, 24 (24.4%) of 98 chickens from Indonesia, 10 (12.5%) of 80 chickens from Italy, 6 (30%) of 20 chickens from Poland, and 81 (24.2%) of 330 chickens from Vietnam. Hearts and brains of chickens were bioassayed for T. gondii. Viable T. gondii was isolated from 2 chickens from Ghana, 1 chicken from Indonesia, 3 chickens from Italy, 2 chickens from Poland, and 1 chicken from Vietnam. Toxoplasma gondii isolates from 9 chickens were genotyped using 10 PCR-RFLP markers including SAG1, SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, and Apico. A total of 7 genotypes was identified; the 3 isolates from chickens from Italy were clonal type II, and the others were nonclonal. This is the first report of genetic characterization of T. gondii isolates from animals from these countries.


Subject(s)
Chickens/parasitology , Poultry Diseases/epidemiology , Toxoplasma/isolation & purification , Toxoplasmosis, Animal/epidemiology , Animals , Antibodies, Protozoan/blood , Biological Assay/veterinary , Cats , DNA, Protozoan/chemistry , Female , Genotype , Ghana/epidemiology , Indonesia/epidemiology , Italy/epidemiology , Mice , Poland/epidemiology , Polymerase Chain Reaction/veterinary , Polymorphism, Restriction Fragment Length , Poultry Diseases/parasitology , Seroepidemiologic Studies , Toxoplasma/classification , Toxoplasma/genetics , Toxoplasma/immunology , Toxoplasmosis, Animal/parasitology , Vietnam/epidemiology
5.
Clin Neurophysiol ; 119(2): 418-28, 2008 Feb.
Article in English | MEDLINE | ID: mdl-18077207

ABSTRACT

OBJECTIVE: This study investigated if obstructive sleep apnea syndrome (OSAS) may be associated with higher activity in different frequency bands of the EEG during a sustained wakefulness paradigm. METHODS: Twelve OSA patients and 8 healthy controls were studied with the Karolinska Drowsiness Test (KDT) and subjective ratings of sleepiness (VAS and KSS) conducted every hour during 24 h of sustained wakefulness. RESULTS: The waking EEG activity, mainly in the low (0.5-7.8 Hz) and fast (12.7-29.2 Hz) frequency band, increased as time awake progressed in both groups but more obviously in OSA patients. A similar pattern was observed for rated sleepiness in both groups. Moreover, VAS ratings of alertness were closely related to the awake theta, fast alpha and beta bands in controls but not in OSA patients. CONCLUSIONS: OSAS was associated with a wake-dependent increase in low (0.5-7.8 Hz) and fast (12.7-29.2 Hz) frequency range activity. Variations in behavioural sleepiness measured by VAS ratings closely reflect most of the waking EEG parameters in controls but not in OSA patients. SIGNIFICANCE: In a sustained wakefulness paradigm, higher activity in delta, theta and beta bands associated with OSAS indicates that OSA patients show marked signs of higher sleepiness and stronger efforts than controls to stay awake, even though they tend to underestimate their sleepiness.


Subject(s)
Electroencephalography , Sleep Apnea, Obstructive/physiopathology , Sleep/physiology , Wakefulness/physiology , Adult , Case-Control Studies , Female , Humans , Male , Middle Aged , Periodicity , Polysomnography , Spectrum Analysis/methods
6.
Parassitologia ; 49(1-2): 7-15, 2007 Jun.
Article in English | MEDLINE | ID: mdl-18412038

ABSTRACT

This review updates those written by Dubey and Beattie in 1988 (1988a) and by Tenter et al in 2000, on pathological and epidemiological aspects of Toxoplasma infection in horses. Under natural conditions, seroprevalence may variate from 0% up to 90%. This wide variation may be due to the sensitivity of the serological methods, to the age of animals, to the geographical area, and even to the hygienic condition of the farms and farm management. With few exceptions, horses are considered one of the less sensitive specie to the pathogenic effect of Toxoplasma gondii. In fact, neither under experimental nor under natural condition a genuine pathologic picture related to the toxoplasmic infection has been described. In one occasion the organism has been isolated from an eye condition and in others a connection between a higher frequency of unspecified pathological conditions and a positive response to serological test for Toxoplasma has been speculated. Diaplacental transmission and the following abortion have been only occasionally reported, and at least in one case in a quite trustworthy way, therefore it must be considered possible, though rare. Although infection of humans due to the consumption of horse meat has never been reported, the existence of a possible risk arouses by the demonstration of the presence of parasite stages in either naturally or experimentally infected horses, which resulted to be infective for mice and/or cats.


Subject(s)
Horse Diseases , Toxoplasmosis, Animal , Abortion, Veterinary/parasitology , Animals , Antibodies, Protozoan/blood , Cats , Female , Fetal Diseases/parasitology , Fetal Diseases/veterinary , Horse Diseases/congenital , Horse Diseases/epidemiology , Horse Diseases/parasitology , Horses/parasitology , Host-Parasite Interactions , Humans , Male , Meat/adverse effects , Meat/parasitology , Mice , Pregnancy , Seroepidemiologic Studies , Toxoplasma/immunology , Toxoplasmosis, Animal/congenital , Toxoplasmosis, Animal/epidemiology , Toxoplasmosis, Animal/parasitology , Toxoplasmosis, Animal/transmission , Toxoplasmosis, Ocular/veterinary
7.
Ann N Y Acad Sci ; 969: 314-7, 2002 Oct.
Article in English | MEDLINE | ID: mdl-12381611

ABSTRACT

A longitudinal study of tick-borne diseases (TBDs) in Southern Italy was carried out by monitoring two dairy farms (A and B) located in the Apulia Region. On each farm ten calves and ten heifers were observed monthly from May 1999 to February 2001 for clinical signs and blood parameters; antibodies against Babesia bigemina and Anaplasma marginale using an ELISA test were also monitored for the first eight months of the study. Totals of 28 and 14 cases of TBDs were observed in the complete herds of Farms A and B, respectively. Timing of disease appearance, categories of animals affected and changes in blood parameters are discussed.


Subject(s)
Anaplasmosis/epidemiology , Babesiosis/veterinary , Cattle Diseases/epidemiology , Anaplasma/immunology , Anaplasmosis/microbiology , Animals , Antibodies, Bacterial/blood , Antibodies, Protozoan/blood , Babesia/immunology , Babesiosis/epidemiology , Babesiosis/parasitology , Cattle , Cattle Diseases/microbiology , Cattle Diseases/parasitology , Enzyme-Linked Immunosorbent Assay/methods , Enzyme-Linked Immunosorbent Assay/veterinary , Female , Italy/epidemiology , Longitudinal Studies , Seroepidemiologic Studies
8.
Neurosci Biobehav Rev ; 25(2): 175-91, 2001 Mar.
Article in English | MEDLINE | ID: mdl-11323082

ABSTRACT

Consciousness remains an elusive concept due to the difficulty to define what has been regarded for many years as a subjective experience, therefore irrelevant for scientific study. Recent development in this field of research has allowed to provide some new insight to a possible way to define consciousness. Going through the extensive literature in this domain, several perspectives are proposed to define this concept. (1) Consciousness and Attention may not reflect the same process. (2) Consciousness during wake and sleep may not involve the same mechanisms. (3) Besides physiological states of consciousness, human beings can experience modified states of consciousness either by self-training (transcendental meditation, hypnosis, etc.) or by drug intake (hallucinogens, anaesthetics, etc.). Altogether, we address the question of a more precise terminology, given the theoretical weight words can convey. To this respect, we propose different definitions for concepts like consciousness, vigilance, arousal and alertness as candidates to separate functional entities.


Subject(s)
Consciousness/physiology , Animals , Attention/physiology , Humans , Sleep/physiology , Wakefulness/physiology
9.
Chronobiol Int ; 17(6): 795-805, 2000 Nov.
Article in English | MEDLINE | ID: mdl-11128296

ABSTRACT

A circadian rhythm for visual sensitivity has been intensively assessed in animals. This rhythm may be due to the existence of a circadian clock in the mammalian eye, which could account for fluctuating sensitivity to light over the day in certain species. However, very few studies have been devoted to the human visual system. The present experiment was designed to assess a possible rhythm of visual sensitivity using a psychophysical method over the whole 24h period. Twelve subjects underwent visual detection threshold measures in a protocol that allowed one point every 2h. The results show that the visual detection threshold changes over the 24h period, with high thresholds in the morning, a progressive decrease over the day and the early night, and an increase during the last part of the night. These data suggest that a circadian rhythm influences visual sensitivity to mesopic luminance in humans.


Subject(s)
Circadian Rhythm/physiology , Vision, Ocular/physiology , Adult , Female , Humans , Male , Photic Stimulation , Photoperiod , Psychophysics
10.
Chronobiol Int ; 17(2): 187-95, 2000 Mar.
Article in English | MEDLINE | ID: mdl-10757463

ABSTRACT

The present experiment was designed to assess daily fluctuations of visual discriminability, a function reflecting the resolution power of the visual sensitivity by measure of a differential threshold. Sixteen subjects underwent a visual discrimination threshold task (using the constant method) in a protocol allowing one point every 2h over the 24h period. The results show that the visual discrimination threshold is low in the morning and increases progressively over the day, reaching a first peak at 22:00. During the night, the same pattern occurs, with low threshold levels at the beginning of the night and high levels at the end. This profile is quite different from that of detection threshold variations, suggesting that the two visual functions are under the control of different underlying mechanisms. Two interpretations could account for this discrepancy. The first relates to different oscillators in the eye for detection and discrimination. The second refers to a possible linkage of visual discriminability with the sleep-wake cycle since threshold measures were systematically low (i.e., high resolution power) after long sleep periods.


Subject(s)
Circadian Rhythm/physiology , Visual Acuity/physiology , Adult , Arousal/physiology , Body Temperature/physiology , Differential Threshold/physiology , Female , Humans , Male , Photic Stimulation , Reaction Time/physiology , Retina/physiology , Sleep/physiology
11.
Percept Mot Skills ; 89(2): 626-8, 1999 Oct.
Article in English | MEDLINE | ID: mdl-10597598

ABSTRACT

The visual discrimination threshold can be considered as an image of the resolution power of the visual system. Measured with a psychophysical method, it shows a diurnal pattern with a low threshold in the morning, i.e., high sensitivity and an increase in the afternoon that persists until the early evening.


Subject(s)
Circadian Rhythm , Discrimination, Psychological , Light , Visual Perception , Adult , Analysis of Variance , Differential Threshold , Humans , Photic Stimulation , Sensory Thresholds , Signal Detection, Psychological
12.
Parassitologia ; 41 Suppl 1: 31-2, 1999 Sep.
Article in English | MEDLINE | ID: mdl-11071538

ABSTRACT

Recently several cases of theileriosis due to the haemoprotozoan Theileria buffeli/orientalis have been recorded in the Apulian region, Italy. In this area other tick-borne pathogens were usually identified such as Anaplasma marginale and Babesia bigemina. Outbreaks were recorded showing that these pathogens can be observed separately or in mixed infections. Sub-clinical cases and carrier animals were also previously identified. A lack of specific techniques could not rule out the presence of other haemoparasites such as T. annulata, B. divergens, B. bovis, Ehrlichia phagocytophila and E. bovis. Moreover little is known about the tick species involved in the dissemination of these diseases. Therefore more powerful techniques to specifically identify Theileria or Babesia species have been recently developed. A PCR technique and reverse line blotting (RLB) system to specifically identify six Theileria species and three Babesia species were used. T. buffeli/orientalis and B. bigemina were the only pathogens observed in the targeted animals. The authors also present some changes in blood parameters for the animals followed during this study.


Subject(s)
Babesia/isolation & purification , Babesiosis/veterinary , Cattle Diseases/diagnosis , Theileria/isolation & purification , Theileriasis/diagnosis , Animals , Babesia/classification , Babesiosis/diagnosis , Babesiosis/parasitology , Cattle , Cattle Diseases/blood , Cattle Diseases/parasitology , Immunosorbent Techniques/veterinary , Italy , Polymerase Chain Reaction/veterinary , Theileria/classification , Theileriasis/parasitology
13.
Chronobiol Int ; 14(1): 35-48, 1997 Jan.
Article in English | MEDLINE | ID: mdl-9042550

ABSTRACT

Visual sensitivity rhythm has been assessed by several authors in animals. It shows an intrinsic circadian rhythm of some retinal mechanisms that could account for fluctuating sensitivity to light during the day in these species. However, very little is known concerning a possible circadian rhythm of visual sensitivity in humans. The present experiment was designed to assess a diurnal rhythm of visual sensitivity using psychophysical methods. Two different detection threshold measures (adaptive and constant methods) were applied on 7 highly entrained subjects. The results show a strongly increased visual detection threshold in the morning (8:00 h) in 4 of 7 subjects, followed by an important improvement at 10:00 h, after which time it remains almost constant whatever the method used. But 3 subjects had constant thresholds throughout the day. A "first session" effect as well as a "chronotype" effect were ruled out. The results are discussed in terms of a possible effect of sleep inertia, suggesting a long-lasting effect probably dependent on the type of task.


Subject(s)
Circadian Rhythm/physiology , Retina/physiology , Retina/radiation effects , Sensory Thresholds/physiology , Adolescent , Adult , Female , Humans , Male , Photic Stimulation , Psychophysics , Reaction Time/physiology , Signal Detection, Psychological/physiology , Sleep/physiology , Surveys and Questionnaires
14.
J Sleep Res ; 4(S2): 67-69, 1995 Dec.
Article in English | MEDLINE | ID: mdl-10607215

ABSTRACT

It seems reasonable to believe that in specific situations napping at the work place would be possible and used if authorized and encouraged. Very short naps could have very positive long-term effects on biological functions. Training someone to sleep for short periods appears feasible if there is a high motivation to do so. Sleep inertia can be considered as one of the main limiting factors in napping strategy. Sleep inertia depends on different factors such as sleep stage preceding the awakening, temporal placement of the nap, duration of nap and wakefulness preceding it, etc. The effects of sleep inertia might be different depending on the type of task, and a reactivation technique applied immediately after awakening may remove it. Despite the fact that its implementation in industry raises some practical issues, napping can be considered as a possible strategy to increase the vigilance level of night workers.

15.
Res Vet Sci ; 58(2): 123-7, 1995 Mar.
Article in English | MEDLINE | ID: mdl-7761689

ABSTRACT

The pharmacokinetic behaviour of aminosidine (15 mg kg-1) and antimony (25.65 mg kg-1 as N-methylglucamine antimoniate), administered subcutaneously either separately or together was studied on four dogs. The results demonstrated that antimony (Sb) did not significantly modify the kinetics of aminosidine (AM) but that the kinetic behaviour of the metal was markedly influenced by the antibiotic, as shown by the differences in mean residence time (MRT), elimination rate constant (Kel) and area under the curve (AUC) with and without the antibiotic (MRT[Sb] = 243.8 +/- 29.5 minutes, MRT[Sb+AM] = 1067.9 +/- 199.2 minutes; Kel[Sb] = 0.008 +/- 0.001 min-1, Kel[Sb+AM] = 0.0015 +/- 0.0003 min-1; AUC[Sb] = 21,024.6 +/- 4448.5 micrograms min ml-1, AUC[Sb+AM] = 130,478.5 +/- 30,481.7 micrograms min ml-1). The persistence of high serum concentrations of antimony when it was administered with aminosidine suggests that the therapeutic doses commonly used should be reduced and that the interval between administration should be increased to avoid the metal reaching toxic concentrations.


Subject(s)
Antiprotozoal Agents/pharmacokinetics , Dogs/metabolism , Meglumine/pharmacokinetics , Organometallic Compounds/pharmacokinetics , Paromomycin/pharmacokinetics , Animals , Dog Diseases/drug therapy , Drug Interactions , Female , Injections, Subcutaneous/veterinary , Leishmaniasis/drug therapy , Leishmaniasis/veterinary , Male , Meglumine Antimoniate , Models, Biological
16.
Minerva Ginecol ; 46(5): 243-8, 1994 May.
Article in Italian | MEDLINE | ID: mdl-7936373

ABSTRACT

Breast pathology, during adolescence, shows a typology like that in adults but with a completely different incidence. We observed 472 patients aged between 12 and 19 years in Senology Center of II Clinic of Obstetrics and Gynecology from 1984 to 1992. The most frequent pathologies diagnosed were: fibroadenomas (in the variety simple, phylloides, giant), cysts (simple and apocrine cysts); lower incidence for congenital anomalies, mastitis, mammary secretion caused by ductal hyperplasia or intraductal papilloma, lipoma. No incidence of cancer was detected. Echography was the principal diagnostic method for those patients who showed, at the clinical examination, a lump or palpable abnormalities. Mammography in this period does not affect the diagnoses and can be potentially harmful due to the exposure at X rays on such a sensible tissue.


Subject(s)
Breast Diseases/diagnosis , Adolescent , Breast/abnormalities , Diagnosis, Differential , Female , Fibroadenoma/diagnosis , Fibrocystic Breast Disease/diagnosis , Humans , Mammography , Mastitis/diagnosis
17.
Res Vet Sci ; 56(2): 144-50, 1994 Mar.
Article in English | MEDLINE | ID: mdl-8191002

ABSTRACT

The pharmacokinetic profile of antimony in dogs was defined by administering it intravenously, intramuscularly and subcutaneously as N-methylglucamine antimoniate at a dose of about 25.65 mg of antimony kg-1 bodyweight. The results showed a different half-life for the three routes of administration: 20.5, 42.1 and 121.6 minutes for the intravenous, intramuscular and subcutaneous routes, respectively; peak time values (Tmax) were also different for the intramuscular (90 to 120 minutes) and subcutaneous (210 to 240 minutes) injection. The apparent bioavailability of antimony was > 100 per cent for the intramuscular and 100 per cent for the subcutaneous routes. The data obtained showed a relevant difference in the behaviour of the drug in the dog in comparison to that in humans.


Subject(s)
Antimony/pharmacokinetics , Meglumine/pharmacokinetics , Organometallic Compounds/pharmacokinetics , Animals , Antimony/blood , Antimony/urine , Biological Availability , Dogs , Female , Half-Life , Injections, Intramuscular/veterinary , Injections, Intravenous/veterinary , Injections, Subcutaneous/veterinary , Male , Meglumine/administration & dosage , Meglumine/blood , Meglumine/urine , Meglumine Antimoniate , Metabolic Clearance Rate , Organometallic Compounds/administration & dosage , Organometallic Compounds/blood , Organometallic Compounds/urine
18.
Percept Mot Skills ; 77(3 Pt 2): 1239-48, 1993 Dec.
Article in English | MEDLINE | ID: mdl-8170772

ABSTRACT

Only a few studies have been devoted to the interaction of noise with sleep deprivation and time of day. In a previous study we demonstrated that noise had an alerting effect on cognitive performance during the early night but not during the late night. However, it was not clear whether these different effects of noise were related to prior sleep debt or to time of day as both factors varied simultaneously. In the present experiment, we further studied this issue to identify which of these two factors was responsible for the noise effects. Analysis showed that, when performance was tested at different times with an equivalent prior sleep debt, noise improved speed of response at 0500 but not at 0800 at which variability of response time increased. Noise had no effect on errors. It is suggested that the effect of noise depends on the underlying arousal and raises arousal from its low level due either to time of day or to partial sleep deprivation.


Subject(s)
Arousal , Circadian Rhythm , Noise , Sleep Deprivation , Adult , Attention , Humans , Male , Reaction Time , Wakefulness
19.
J Chemother ; 5(2): 113-8, 1993 Apr.
Article in English | MEDLINE | ID: mdl-8515293

ABSTRACT

Five hundred and sixty-six women, consecutively admitted to nine different hospitals for elective abdominal hysterectomy, were randomized to receive a single 2 g i.v. dose of either cefotetan or piperacillin at induction of anesthesia. Five patients were excluded and 561 (287 given cefotetan and 274 given piperacillin) could be evaluated. In 10 patients (5 for each drug) the concentrations of either cefotetan or piperacillin in serum and subcutaneous tissue at the beginning and at the end of surgery and in uterus, salpinx and ovary samples, were microbiologically assessed. No significant differences could be found between cefotetan and piperacillin groups for any of the considered infectious complications (bacteremia, wound or vaginal cuff infection, pelvic cellulitis and febrile morbidity) nor for the pooled data (cefotetan group: 4.9%, piperacillin group: 5.8%, p:NS). As for the concentrations of prophylactic drugs, serum levels throughout surgery were found to be adequate.


Subject(s)
Cefotetan/therapeutic use , Hysterectomy/methods , Piperacillin/therapeutic use , Premedication , Adult , Female , Humans , Middle Aged , Prospective Studies , Surgical Wound Infection/prevention & control
20.
Article in English | MEDLINE | ID: mdl-8425516

ABSTRACT

Intermittent noise occurring during sleep has been found to induce heart rate, peripheral vasomotor and electroencephalogram (EEG) changes. This study analysed these responses during the daytime and night-time sleep of shiftworkers doing a three shift system, to determine the influence of the inversion of the sleep-wake cycle on the sensitivity to noise. A group of 14 shiftworkers [aged 37 (SD 5) years] underwent an habituation daytime sleep, two experimental daytime sleeps and a night-time sleep. Traffic noises were presented during sleep [truck, 71 dB(A); motorbike, 67 dB(A); and car, 64 dB(A)] at a rate of nine each hour. The EEG measurements of sleep, electrocardiogram and finger pulse amplitude were recorded continuously. The results were expressed by computing the percentage of observed cardiac response (%HRR) and vasoconstrictive response (%FPR), magnitude of heart rate variation (heart rate response; HRR), percentage of reduction of the digital blood flow (finger pulse response, FPR), cardiac cost (CC = % HRR x HRR) and vasomotor cost (VC = % FPR x FPR). The results showed that, compared to night-time sleep, there was change in the structure of daytime sleep, that is an increase in slow wave sleep (SWS), especially stage 4 sleep decrease of stage 2 and rapid eye movement (REM) sleep latencies, and an earlier SWS and REM sleep barycentric point. During daytime sleep the % FPR was significantly smaller in SWS than in stage 2 or REM sleep. Large differences were observed in % HRR, HRR and CC between daytime sleep stages (SWS less than stage 2 less than REM sleep).(ABSTRACT TRUNCATED AT 250 WORDS)


Subject(s)
Brain/physiology , Cardiovascular Physiological Phenomena , Noise , Sleep/physiology , Adult , Electroencephalography , Employment , Heart Rate/physiology , Humans , Male , Sleep Stages/physiology , Time Factors
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