Biomedical subjects

Sérgio Tufik

Publications and source records attributed to Sérgio Tufik.

16 recordsLinked to original sources

PubMed2006

Clinical, anthropometric and upper airway anatomic characteristics of obese patients with obstructive sleep apnea syndrome.

BACKGROUND: Obese subjects are at increased risk of developing obstructive sleep apnea syndrome (OSAS). However, the individual role of local (i.e., upper airway-related) and general (clinical and whole-body anthropometric) characteristics in determining OSAS in obese patients is still controversial. OBJECTIVES: To contrast the clinical, anthropometric and upper airway anatomical features of obese subjects presenting or not presenting with OSAS. METHODS: Thirty-seven obese (BMI > or =30 kg/m(2)) males with OSAS and 14 age- and gender-matched obese controls underwent clinical and anthropometric (BMI, waist-to-hip ratio and neck circumference) evaluation. In a subgroup of subjects (18 and 11 subjects, respectively), magnetic resonance imaging (MRI) during wakefulness was used to study the upper airway anatomy. RESULTS: OSAS patients showed significantly higher BMI, waist-to-hip ratio and neck circumference as compared to controls (p < 0.05). They also referred to nonrepairing sleep, impaired attention, and previous car accidents more frequently (p < 0.05). The transversal diameter of the airways (TDAW) at the retroglossal level by MRI was found to be an independent predictor of the presence and severity of OSAS (p < 0.05). Parapharyngeal fat increase, however, was not related to OSAS. A TDAW >12 mm was especially useful to rule out severe OSAS (apnea-hypopnea index >30, negative predictive value = 88.9%, likelihood ratio for a negative test result = 0.19). CONCLUSIONS: MRI of the upper airway can be used in association with clinical and anthropometric data to identify obese males at increased risk of OSAS.

Adult↗

PubMed2006

Treatment of moderate obstructive sleep apnea syndrome with acupuncture: a randomised, placebo-controlled pilot trial.

BACKGROUND AND PURPOSE: To investigate the efficacy of acupuncture in the treatment of moderate obstructive sleep apnea syndrome (OSAS), assessed by polysomnography (PSG) and questionnaires of functional quality of life (SF-36) and excessive daytime sleepiness (Epworth). PATIENTS AND METHODS: We performed a randomised, placebo-controlled, single-blinded study, with blinded evaluation on 36 patients presenting an apnea/hypopnea index (AHI) of 15-30/h, assessed by PSG. The study took place at the Public Hospital of the Universidade Federal de São Paulo, Brazil, in the Division of Sleep Disorders of the Department of Psychobiology, between January, 2002 and August, 2004. Patients were randomly assigned to three groups: the acupuncture group (n=12); the sham group, submitted to needle insertion in non-acupoints (n=12); and the control group, receiving no treatment (n=12). Patients received acupuncture or sham acupuncture once a week for 10 weeks. RESULTS: Twenty-six patients completed the study. The AHI (P=0.005), the apnea index (AI) (P=0.008) and the number of respiratory events (P=0.005) decreased significantly in the acupuncture group but not in the sham group. On the other hand, the control group displayed significant deterioration in some of the polysomnographic parameters, with a significant increase in the number of respiratory events (P=0.025). Acupuncture treatment significantly improved (before vs. after treatment) several dimensions of the SF-36 and Epworth questionnaires. There was no significant association between changes in the body mass index (BMI) and AHI. CONCLUSIONS: Acupuncture is more effective than sham acupuncture in ameliorating the respiratory events of patients presenting with moderate OSAS.

Acupuncture Therapy↗

PubMed2006

Sleep bruxism and temporomandibular disorder: Clinical and polysomnographic evaluation.

OBJECTIVE: To seek better understanding of chronic musculoskeletal facial pain and its relation to sleep bruxism, by comparing patients with sleep bruxism, with and without temporomandibular disorder. DESIGN: Forty sleep bruxism patients were evaluated according to the Research Diagnostic Criteria for Temporomandibular Disorders: group A-20 patients with myofascial pain, 3 men, 17 women; average age 32.7yr; mean duration of pain 4.37yr; group B-20 without myofascial pain, 5 men, 15 women; average age 30.8yr. Sleep and bruxism were evaluated in one-night polysomnography. RESULTS: There were no statistically significant differences for bruxism and sleep variables of the two groups: number of bursts and bruxism episodes per hour, amplitude and duration of bruxism episodes, sleep efficiency and latency, percentage of non-REM and REM sleep, respiratory events, periodic limb movements, and micro-arousals. CONCLUSIONS: The polysomnographic characteristics of patients with sleep bruxism, with and without orofacial pain, are similar. More studies are necessary to clarify the reasons why some sleep bruxism patients develop chronic myofascial pain, and others do not.

Adolescent↗

PubMed2006

Nonalcoholic fatty liver disease decrease in obese adolescents after multidisciplinary therapy.

BACKGROUND: Despite the increasing prevalence of nonalcoholic fatty liver disease, its pathogenesis and clinical significance remain poorly defined and there is no ideal treatment. OBJECTIVE: The aim of this study was to assess the short-term (12-week) multidisciplinary therapy on visceral adiposity and nonalcoholic fatty liver disease control. METHODS: We evaluated and compared the distribution of visceral adiposity and nonalcoholic fatty liver disease, by ultrasonography, in 73 post-puberty obese participants (17.01+/-1.6 years old; body mass index 36.54+/-2.86 kg/m), submitted to a multidisciplinary treatment without medications, at the beginning and after 12 weeks of intervention. Descriptive and one-way analysis of variance, and paired t-test were performed. RESULTS: The results indicated that after intervention the adolescents had a significant reduction in visceral adiposity (4.05+/-1.55 to 3.37+/-1.44) and nonalcoholic fatty liver disease prevalence (from 52 to 29% on the right side and from 48 to 29% on the left side). It is a positive result because nonalcoholic fatty liver disease can progress to cirrhosis, even in children and adolescents. CONCLUSIONS: The short-term treatment suggests a profound impact on the control of obesity-related co-morbidities in young people.

Adiposity↗

PubMed2006

Sleep parameters in patients using pacemakers with sleep rate function on.

INTRODUCTION: The cardiovascular system (CVS) is heavily influenced by the autonomic nervous system. Additionally, there is a functional alteration during the various stages of sleep. In nonrapid eye movement (NREM), a state of cardiovascular relaxation occurs during stages three and four. A large amount of rapid ocular movements is concentrated in rapid eye movement (REM) sleep. During this phase, fluctuations in arterial pressure (AP) and heart rate (HR) can be readily noted. Sleep disordered breathing (SDB) has been associated with cardiac rhythm disorders. Recently, cardiac rhythm disorder treatment with pacemaker (PM) highlighted a reduction in abnormal respiratory events during sleep. OBJECTIVE: Comparison of sleep parameters of patients using PM with a sleep rate (SR) algorithm based on its rate-modulated capability during physical activity (Integrity PM with SR function on and off). METHODS: Twenty-two patients (14 women, 8 men), implanted with an Integrity PM (St. Jude Medical Cardiac Rhythm Management Division, Sylmar, CA) with SR function for standard clinical indications, were evaluated utilizing a double-blind protocol. The indication for pacing included sinus node disease (SND), atrium ventricular blockage (AVB), and atrial fibrillation (AF). Following randomization, half of our patients had SR function switched to "on" mode while the other half were on "off" mode. During the first stage of the protocol, all patients underwent two consecutive nights of polysomnographic sleep recordings (PSG). During the first night patients slept in the sleep lab only for adaptation purpose. PSG full recording was carried out in the subsequent night. At a later stage, the programing of SR functions was shifted to "on" or "off" modes. One week later, a third assessment was undertaken. RESULTS: Twelve patients (54%) showed sleep efficiency improvement (total sleeping time/recording time) with PM SR on. This group had the least effective sleep efficiency with PM off, if compared with the others who highlighted no change in this sleep parameter (72 +/- 12 vs 81 +/- 7%, P = 0.01, respectively). This first group displayed a lower latency for REM sleep than the last one (89 +/- 55 vs 174 +/- 107 minutes, P = 0.01, respectively). In 11 (50%) patients, the number per sleep hour of microarousals was reduced when PM SR was switched on. When we compared such findings to the group whose parameters had not changed, we noted that the first set of patients were sleepier (ESE: 9 +/- 4 vs 5 +/- 5, P = 0.04, respectively), and showed more microarousals with PM SR off (20 +/- 14 vs 7 +/- 5 microarousal/hour, P = 0.007). CONCLUSION: In PM patients with sleep-related issues, the SR function activation improved sleep both from a qualitative and quantitative perspective.

Aged↗

PubMed2006

Visual and automatic cyclic alternating pattern (CAP) scoring: inter-rater reliability study.

The classification of short duration events in the EEG during sleep, as the A stage of the cyclic alternating pattern (CAP) is a tedious and error prone task. The number of events under normal conditions is large (several hundreds), and it is necessary to mark the limits of the events with precision, otherwise the time sensitive classification of the CAP phases (A and B) and specially the scoring of different types of A phases will be compromised. The objective of this study is to verify the feasibility of visual CAP scoring with only one channel of EEG, the evaluation of the inter-scorer agreement in a variety of recordings, and the comparison of the visual scorings with a known automatic scoring system. Sixteen hours of one channel (C4-A1 or C3-A2) of NREM sleep were extracted from eight whole night recordings in European Data Format and presented to the different scorers. The average inter-scorer agreement for all scorers is above 70%, the pair wise inter-scorer agreement found was between 69% up to 77.5%. These values are similar to what has been reported in different type studies. The automatic scoring system has similar performance of the visual scorings. The study also has shown that it is possible to classify the CAP using only one channel of EEG.

Electroencephalography↗

PubMed2006

[Effects of acute exercise on postprandial lipemia in sedentary men].

OBJECTIVE: To examine the effects of a single session of isometric physical exercise on postprandial triglyceridemia in sedentary male individuals with fasting triglycerides values < 150 mg/dl (NTG) or > " 150 mg/dl (TG ALT). METHODS: Twenty-seven individuals (10 NTG and 17 TG ALT), aged between 30-55 years were assessed in the study. Triglycerides were determined in the beginning, and at two, four and six hours after the oral ingestion of a solution with 50 g/m2 of fat in two occasions: at rest and after treadmill isometric exercise. RESULTS: Acute exercise did not affect the levels of postprandial triglycerides or the area under the curve (AUC) of triglycerides. However, the abnormal pattern of postprandial lipemia curve was associated with higher basal triglyceridemia with exercise (basal TG: 147 +/- 90 vs. 238 +/- 89 mg/dl, p = 0.02) and without exercise (basal TG: 168 +/- 93 vs. 265 +/- 140 mg/dl, p = 0.04). Analysis of the receiver operating characteristics (ROC) curves showed cut-off values for basal triglycerides with exercise of 166.5 mg/dl (sensitivity: 0.78; specificity: 0.72) and AUC of 0.772 [CI 95%: 0.588-0.955], and without exercise of 172 mg/dl (sensitivity: 0.78; specificity: 0.61) and AUC: 0.722 [CI 95%: 0.530-0.914]. CONCLUSION: Acute exercise did not affect postprandial triglyceridemia in sedentary male individuals, and basal triglyceride levels are predictors of an abnormal response of postprandial triglycerides.

Adult↗

PubMed2005

Adult Chiari malformation and sleep apnoea.

Chiari malformation (CM) is primarily characterised by herniation of the cerebellar tonsils through the foramen magnum. Clinically, two main types of CM represent the vast majority of cases: type I (in adults) and type II (in infants). CM may result in neuronal impairment of the brainstem, upper spinal cord and cranial nerves. Part of the afferent and efferet systems and the central respiratory controlling system are located in the cranium-cervical transition and may be damaged in these pathologies, leading to respiratory disorders, such as respiratory failure and death. The ventilatory responses to exogenous and endogenous stimuli, such as responses to hypoxia and hypercapnia, are usually diminished, and apnea may be manifested and detected during sleep, allowing for the diagnosis. This study is a review of the relationship between sleep apnoea and adult CM.

Arnold-Chiari Malformation↗

PubMed2005

Prevalence of myocardial infarction is related to hyperhomocysteinemia but not influenced by C677T methylenetetrahydrofolate reductase and A2756G methionine synthase polymorphisms in diabetic and non-diabetic subjects.

BACKGROUND: Hyperhomocysteinemia has emerged as a novel risk factor for myocardial infarction (MI). Some mechanisms proposed to explain its relationship with coronary events are also shared by major coronary risk factors. We examined whether C677T methylenetetrahydrofolate reductase and A2756G methionine synthase polymorphisms could affect the relative risk for MI. METHODS: A sample of 196 individuals was divided into four groups (diabetics with MI, n=43; diabetics without MI, n=50; non-diabetics with MI, n=47; non-diabetics without MI, n=56) and compared regarding the prevalence of the polymorphisms, risk factors, and biochemical parameters. RESULTS: Higher prevalence of hyperhomocysteinemia was found in MI patients (p<0.05 vs. non-MI subjects), in males (p<0.001 vs. female) and in those > or = 65 years (p=0.01 vs. <65 years). Homocysteine was negatively associated with HDL-C (p<0.05) and glucose, although results did not reach significance (p=0.06). Similar distribution of studied polymorphisms was seen in all groups, which presented normal folate and vitamin B12 serum levels. CONCLUSIONS: Higher homocysteinemia was predominantly observed in men, presenting low HDL-C, and at advancing age. Methylenetetrahydrofolate reductase and methionine synthase polymorphisms did not contribute to risk assessment in diabetic and non-diabetic subjects presenting normal folate levels.

5-Methyltetrahydrofolate-Homocysteine S-Methyltran↗

PubMed2005

OSAS in children: correlation between endoscopic and polysomnographic findings.

OBJECTIVES: To correlate polysomnographic findings with clinical history of apnea, the degree of obstruction caused by tonsillar hypertrophy, and to age group. STUDY DESIGN AND SETTING: 267 children with a clinical diagnosis of obstructive sleep apnea (OSAS) were evaluated. Patients were divided into preschool- and school-age categories, and subdivided in 3 additional groups, according to tonsillar hypertrophy. Polysomnographic findings were compared within groups. RESULTS: 34% of children had history of OSAS and normal polysomnographic findings. Tonsillar hypertrophy was correlated to more severe apnea among preschool-age children, but not among school-age children. Among children with tonsillar hypertrophy, more severe apnea was observed in preschool-age children than in school-age children. CONCLUSIONS: There is little correlation between polysomnographic and clinical findings in children with OSAS. SIGNIFICANCE: Adenotonsillar hypertrophy leads to more severe polysomnographic patterns in preschool-age children. More severe apnea is observed in younger children with adenotonsillar hypertrophy than in older ones.

Adenoids↗

PubMed2004

Serotonin involvement in the electroacupuncture- and moxibustion-induced gastric emptying in rats.

OBJECTIVE: Electroacupuncture (EA) as well as moxibustion stimulation has been reported to produce an excitatory effect on the gastrointestinal motility of the rat. Serotonergic neurons of the mioenteric and submucous plexus are major participants in the gastrointestinal physiology. Here, we compared the outcomes of the stimulation of a specific set of acupoints with either acupuncture or moxibustion on the gastrointestinal motility and the role of serotonin (5-HT) in this effect. METHODS: To analyze the role of 5-HT on the gastrointestinal motility of the rat, we studied the flow of 25 glass beads administered to the stomach, after treatment of the animals with a serotonin inhibitor (para-chlorophenylalanine [pCPA]). Acupuncture stimulation was performed on acupoints St-36 (Zusanli) and Sp-6 (Sanyinjiao), with electrical stimulation, or on acupoints Ren-10 (Xiawan), Ren-12 (Zhongwan) and St-25 (Tianshu), with moxibustion. Animals subjected to sham stimulation were used as controls in addition to naive, unstimulated animals. RESULTS: Stimulation of the hind limb (St-36 and Sp-6) and abdominal (Ren-10, Ren-12, St-25) acupoints resulted in effective gastric emptying, as compared with sham-stimulated animals. Pretreatment of animals with pCPA abolished either the response provided by acupuncture stimulation in animal groups subjected to hind limb acupoints or the response provided by moxibustion stimulation in abdominal acupoints. CONCLUSION: Our data suggest that moxibustion in the abdominal points and EA in the hind limb require an intact serotonergic pathway. In addition, we suggest that this involvement of serotonin is a general feature of the mediated effects of acupuncture on gastric emptying of the rat.

Acupuncture Points↗

PubMed2003

Risk Factors, biochemical markers, and genetic polymorphisms in early coronary artery disease.

OBJECTIVE: To assess the risk factors, lipid and apolipoprotein profile, hemostasis variables, and polymorphisms of the apolipoprotein AI-CIII gene in early coronary artery disease (CAD). METHODS: Case-control study with 112 patients in each group controlled by sex and age. After clinical evaluation and nutritional instruction, blood samples were collected for biochemical assays and genetic study. RESULTS: Familial history of early CAD (64 vs 39%), arterial hypertension (69 vs 36%), diabetes mellitus (25 vs 3%), and previous smoking (71 vs 46%) were more prevalent in the case group (p<0.001). Hypertension and diabetes were independent risk factors. Early CAD was characterized by higher serum levels of total cholesterol (235 +/-6 vs 209 +/- 4 mg/dL), of LDL-c (154 +/- 5 vs 135 +/- 4 mg/dL), triglycerides (205 +/- 12 vs 143 +/- 9 mg/dL), and apolipoprotein B (129 +/- 3 vs 105 +/- 3 mg/dL), and lower serum levels of HDL-c (40 +/- 1 vs 46 +/- 1 mg/dL) and apolipoprotein AI (134 +/- 2 vs 146 +/- 2mg/dL) [p<0.01], in addition to an elevation in fibrinogen and D-dimer (p<0.02). The simultaneous presence of the rare alleles of the APO AI-CIII genes in early CAD are associated with hypertriglyceridemia (p=0.03). CONCLUSION: Of the classical risk factors, hypertension and diabetes mellitus were independently associated with early CAD. In addition to an unfavorable lipid profile, an increase in the thrombotic risk was identified in this population. An additive effect of the APO AI-CIII genes was observed in triglyceride levels.

Adult↗

PubMed2003

Flunitrazepam-induced changes in neurophysiological, behavioural, and subjective measures used to assess sedation.

INTRODUCTION: Certain features of event-related potentials (ERPs), electroencephalographic (EEG), and behavioural measures vary with differing states of alertness and/or sedation. PURPOSE: This study was conducted to investigate changes in several measures usually viewed as reflecting states of sedation/sleepiness associated with the use of a range of doses of the hypnotic benzodiazepine (BZD) flunitrazepam (FNZ). METHODS: This was a double blind, independent group design study of the effects of acute oral doses of FNZ in young healthy volunteers. Forty-eight subjects were randomly allocated to one of four groups-FNZ (0.6, 0.8, and 1.0 mg) and placebo (PLAC)-and tested prior to treatment and then in a posttreatment session close to the theoretical peak plasma concentration. ERP latencies and amplitudes were measured at midfrontal (Fz), midcentral (Cz), and midparietal (Pz) using a standard auditory oddball paradigm. EEG changes were assessed at Pz. Behavioural measures included the digit-symbol substitution test (DSST), a cancellation task (CT), and subjective ratings of alertness and attentiveness by the subjects (SUB) and the experimenter (EXP). RESULTS: FNZ led to psychomotor impairments and decreased alertness and attention; these effects were consistent with previous findings. A progressive, dose-related increase in P3 latency occurred in Fz, Cz, and Pz, and there was an increase in N1 (Fz, Cz) and N2 (Fz). N2-P3 amplitude decreased in Fz. EEG power bands beta 1 increased for the two highest doses, but no significant differences were noted in theta, delta, and alpha bands. P3 latencies, experimenter-rated levels of alertness, and DSST scores differentiated all three doses of FNZ from PLAC. CONCLUSION: The most sensitive measures used were P3 latencies of the ERPs (which varied with FNZ dose), DSST, and the experimenter-rated levels of alertness. However, we found no evidence for the assumption that one single phenomenon was reflected in all measures and different mechanisms were probably involved. Further experiments will be needed for more in-depth probing of the finer mechanisms underlying sedation/sleepiness and how they affect behavioural and eletrophysiological measures of the central nervous system (CNS) function.

Adolescent↗

PubMed2002

Effects of mandibular posture on obstructive sleep apnea severity and the temporomandibular joint in patients fitted with an oral appliance.

STUDY OBJECTIVES: The purposes of this study were to assess the relationship between different increments of mandibular protrusion and a reduction of obstructive sleep apnea (OSA) severity and to use magnetic resonance imaging to assess temporomandibular joint (TMJ) morphology and condyle position after the insertion of an oral appliance (OA). DESIGN: Six mild to moderate OSA patients were treated with a titratable OA (Klearway) and changes in the apnea hypopnea index (AHI) secondary to the amount of mandibular advancement were evaluated. In seven patients, the morphology of the TMJ was compared before insertion and after titration of the appliance and the anterior displacement of the condyle with the titrated appliance in place was evaluated. SETTING: Federal University of São Paulo, Brazil. PATIENTS OR PARTICIPANTS: 7 males (mean age 47.4 years, SD 5.6). INTERVENTIONS: N/A. MEASUREMENTS AND RESULTS: A total of 21 polysomnographic recordings in different mandibular positions were compared. A significant reduction in the mean AHI from 12.21 to 5.64 was seen and the the AHI reduction was related to the amount of mandibular protrusion. In six out of seven patients, the translation of the condyle with the OA was equal to or less than that observed in the maximal open position. No TMJ morphologic parameters revealed significant alterations during the period of the study. CONCLUSION: Sequential polysomnographic studies facilitate OA titration. OA effects on the AHI seem to be dose-dependent on the amount of mandibular protrusion, and the OA proved over the period of one year to be innocuous for TMJ in the treatment of patients with OSA.

Adult↗

PubMed2002

Acute or chronic effects of cannabinoids on spontaneous or pharmacologically induced yawning in rats.

Yawning is a reflex or event that is not fully understood. It is controlled by many neurotransmitters and neuropeptides and can be induced pharmacologically by cholinergic or dopaminergic agonists. Amongst their many actions, cannabinoids acting on cannabinoid (CB(1) or CB(2)) receptors can alter cholinergic and/or dopaminergic activity. This study examined the effects of Delta(8)-tetrahydrocannabinol (Delta(8)-THC) administered acutely (2.5 mg/kg intraperitoneally [ip], 15 min before test) or chronically (5 mg/kg for 30 days followed by 24 h or 7 days of discontinuation) on yawning induced by pilocarpine, a cholinergic agonist (0, 1, 2, 4 or 8 mg/kg ip), or apomorphine, a dopaminergic agonist (0, 20, 40 or 80 microg/kg subcutaneously [sc]). Acute effects of different doses of Delta(9)-tetrahydrocannabinol (Delta(9)-THC: 0, 0.5, 1.25 or 2.5 mg/kg ip) on yawning induced by pilocarpine (2 mg/kg ip) or apomorphine (40 microg/kg sc) were also investigated. Both pilocarpine and apomorphine produced yawning in a dose-related manner. Acute administration of Delta(8)-THC and Delta(9)-THC significantly reduced yawning induced by both pilocarpine and apomorphine. Chronic administration of Delta(8)-THC did not change yawning induced by either agonist 24 h or 7 days after discontinuation of Delta(8)-THC. However, a high frequency of spontaneous yawning was observed 7 days after Delta(8)-THC discontinuation. These results suggest that cannabinoid agonists inhibited yawning induced by cholinergic or dopaminergic agonists. In addition, the increased frequency of spontaneous yawning following cessation of chronic administration of a cannabinoid agonist may be of importance as a withdrawal sign for these drugs.

Animals↗

PubMed2002

Sleep deprivation does not affect indices of necrosis or apoptosis in rat brain.

Recent indications of oxidative stress in hypothalamus of sleep deprived rats prompted us to address the possibility that sleep deprivation may induce pathological cell loss changes in brain. Indices of necrosis and apoptosis were quantified after 96 h of sleep deprivation induced by the classical platform technique in rats. Binding of the "peripheral-type" benzodiazepine ligand [3H]PK 11195 to reactive astrocytes, a reliable and sensitive index of necrotic changes, was not altered in any of 14 brain regions examined. Likewise, no changes were found in mRNA levels of the apoptosis-related genes bcl-2 and bax in any of 24 brain regions examined. This was corroborated by quantitative TUNEL analyses in hypothalamus, amygdala, and cortex, which also revealed no effects in sleep deprived animals. These results are consistent with other recent evidence that sleep deprivation does not induce necrotic or apoptotic cell loss in brain. This suggests that recent findings of oxidative stress in sleep deprived brains do not result in cell loss. The possibility that sleep deprivation may result in functional deficits, or that structural changes may emerge after repeated episodes of sleep deprivation, remains to be addressed.

Animals↗