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1.
Chronobiol Int ; 38(8): 1135-1142, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33906520

RESUMO

Chronotype or diurnal preference is a questionnaire-based measure influenced both by circadian period and by the sleep homeostat. In order to further characterize the biological determinants of these measures, we used a hypothesis-free approach to investigate the association between the score of the morningness-eveningness questionnaire (MEQ) and the Munich chronotype questionnaire (MCTQ), as continuous variables, and volumetric measures of brain regions acquired by magnetic resonance imaging (MRI). Data were collected from the Baependi Heart Study cohort, based in a rural town in South-Eastern Brazil. MEQ and anatomical 1.5-T MRI scan data were available from 410 individuals, and MCTQ scores were available from a subset of 198 of them. The average MEQ (62.2 ± 10.6) and MCTQ (average MSFsc 201 ± 85 min) scores were suggestive of a previously reported strong general tendency toward morningness in this community. Setting the significance threshold at P > .002 to account for multiple comparisons, we observed a significant association between lower MEQ score (eveningness) and greater volume of the left anterior occipital sulcus (ß = -0.163, p = .001) of the occipital lobe. No significant associations were observed for MCTQ. This may reflect the smaller dataset for MCTQ, and/or the fact that MEQ, which asks questions about preferred timings, is more trait-like than the MCTQ, which asks questions about actual timings. The association between MEQ and a brain region dedicated to visual information processing is suggestive of the increasingly recognized fluidity in the interaction between visual and nonvisual photoreception and the circadian system, and the possibility that chronotype includes an element of masking.


Assuntos
Ritmo Circadiano , Vigília , Encéfalo/diagnóstico por imagem , Brasil , Humanos , Lobo Occipital/diagnóstico por imagem , Sono , Inquéritos e Questionários
2.
Sci Rep ; 6: 39283, 2016 12 23.
Artigo em Inglês | MEDLINE | ID: mdl-28008932

RESUMO

Sleep is modulated by several factors, including sex, age, and chronotype. It has been hypothesised that contemporary urban populations are under pressure towards shorter sleep duration and poorer sleep quality. Baependi is a small town in Brazil that provides a window of opportunity to study the influence of sleep patterns in a highly admixed rural population with a conservative lifestyle. We evaluated sleep characteristics, excessive daytime sleepiness, and chronotype using the Pittsburgh Sleep Quality Index, Epworth Sleepiness Scale and Morningness-Eveningness Questionnaire questionnaires, respectively. The sample consisted of 1,334 subjects from the Baependi Heart study (41.5% male; age: 46.5 ± 16.2 y, range: 18-89 years). Average self-reported sleep duration was 07:07 ± 01:31 (bedtime 22:32 ± 01:27, wake up time: 06:17 ± 01:25 hh:min), sleep quality score was 4.9 + 3.2, chronotype was 63.6 ± 10.8 and daytime sleepiness was 7.4 ± 4.8. Despite a shift towards morningness in the population, chronotype remained associated with reported actual sleep timing. Age and sex modulated the ontogeny of sleep and chronotype, increasing age was associated with earlier sleep time and shorter sleep duration. Women slept longer and later, and reported poorer sleep quality than men (p < 0.0001). This study provides indirect evidence in support of the hypothesis that sleep timing was earlier prior to full urbanisation.


Assuntos
Higiene do Sono , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Brasil , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , População Rural , Fatores Sexuais , Inquéritos e Questionários , Fatores de Tempo , Adulto Jovem
3.
Acta Otorhinolaryngol Ital ; 36(4): 317-320, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27734985

RESUMO

Mandibular fracture is usually the clinical end of bisphosphonate-related osteonecrosis of the jaw. This is a painful complication and patients cannot feed as usual, with a worsening of their quality of life. The goal of treatment in bisphosphonate related osteonecrosis of jaw (BRONJ) patients is to slow progression of bone necrosis. We present a novel technique for treatment of severe mandibular BRONJ in stage 3 patients that present with a high risk to develop fracture, since they have a residual unaffected mandibular bone height less than 6 mm. We treated 10 patients in this clinical situation with an extra-oral application of a reconstructive plate superficial to the platysma, to keep the plate separated from the infected site to avoid contamination and consequent need of removal, followed by an intraoral approach for active curettage of mandibular necrosis. The preservation of blood supply to the mandible and avoidance of direct contact of the infected site with the reconstructive plate are some advantages of this technique. This plate allows enhancement of mandibular strength, allowing proper treatment of the BRONJ site on the oral side without fear of causing a mandibular fracture when the residual mandible is thin. This technical solution guarantees these patients an extended disease-free period since it is effective in preventing mandibular fractures in patients with low mandibular residual height left after the BRONJ onset.


Assuntos
Osteonecrose da Arcada Osseodentária Associada a Difosfonatos/complicações , Fraturas Mandibulares/etiologia , Fraturas Mandibulares/prevenção & controle , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
4.
Braz J Med Biol Res ; 49(10): e5311, 2016 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-27737315

RESUMO

The objective of this study was to evaluate the alterations in sleep and circadian parameters during the aging process. The study sample comprises volunteers older than 18 up to 90 years of age that answered the Pittsburgh Sleep Quality Index (PSQI) and the Horne and Östberg circadian preference questionnaire. We observed that the shift to morningness with increasing age is associated with a significant worsening in sleep quality. We discuss that this sleep profile characterized by morningness and worse sleep quality observed in elderly, when compared to younger people, reflects not necessarily a pathological state, but an expected profile for this age group.


Assuntos
Envelhecimento/fisiologia , Transtornos do Sono-Vigília/fisiopatologia , Sono/fisiologia , Fatores Etários , Idoso , Análise de Variância , Temperatura Corporal/fisiologia , Ritmo Circadiano/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Autorrelato , Estatísticas não Paramétricas , Fatores de Tempo , Adulto Jovem
5.
Braz. j. med. biol. res ; 49(10): e5311, 2016. tab, graf
Artigo em Inglês | LILACS | ID: biblio-951652

RESUMO

The objective of this study was to evaluate the alterations in sleep and circadian parameters during the aging process. The study sample comprises volunteers older than 18 up to 90 years of age that answered the Pittsburgh Sleep Quality Index (PSQI) and the Horne and Östberg circadian preference questionnaire. We observed that the shift to morningness with increasing age is associated with a significant worsening in sleep quality. We discuss that this sleep profile characterized by morningness and worse sleep quality observed in elderly, when compared to younger people, reflects not necessarily a pathological state, but an expected profile for this age group.


Assuntos
Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Adulto Jovem , Sono/fisiologia , Transtornos do Sono-Vigília/fisiopatologia , Envelhecimento/fisiologia , Qualidade de Vida , Fatores de Tempo , Temperatura Corporal/fisiologia , Análise de Variância , Fatores Etários , Ritmo Circadiano/fisiologia , Estatísticas não Paramétricas , Autorrelato
6.
Biomed Res Int ; 2014: 170795, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24982860

RESUMO

The aim of this study was to analyse the circadian behavioural responses of mice carrying a functional knockout of the Per3 gene (Per3(-/-)) to different light : dark (L : D) cycles. Male adult wild-type (WT) and Per3(-/-) mice were kept under 12-hour light : 12-hour dark conditions (12L : 12D) and then transferred to either a short or long photoperiod and subsequently released into total darkness. All mice were exposed to both conditions, and behavioural activity data were acquired through running wheel activity and analysed for circadian characteristics during these conditions. We observed that, during the transition from 12L : 12D to 16L : 8D, Per3(-/-) mice take approximately one additional day to synchronise to the new L : D cycle compared to WT mice. Under these long photoperiod conditions, Per3(-/-) mice were more active in the light phase. Our results suggest that Per3(-/-) mice are less sensitive to light. The data presented here provides further evidence that Per3 is involved in the suppression of behavioural activity in direct response to light.


Assuntos
Ritmo Circadiano , Proteínas Circadianas Period/deficiência , Fotoperíodo , Animais , Feminino , Luz , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas Circadianas Period/metabolismo
7.
Braz J Med Biol Res ; 47(4): 316-20, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24714814

RESUMO

Chronotype is an established concept designed to identify distinct phase relationships between the expression of circadian rhythms and external synchronizers in humans. Although it has been widely accepted that chronotype is subjected to ontogenetic modulation, there is no consensus on the interaction between age and gender. This study aimed to determine the relationship between age- and gender-related changes in the morningness-eveningness character in a large sample of people. A total of 14,650 volunteers were asked to complete the Brazilian version of the Horne and Östberg chronotype questionnaire. The data demonstrated that, on average, women were more morning-oriented than men until the age of 30 and there were no significant differences between men and women from 30 to 45 years of age. In contrast to the situation observed until the age of 30, women older than 45 years were more evening-oriented than men. These results suggest that the ontogenetic development of the circadian timekeeping system is more plastic in men, as represented by the larger amplitude of chronotype changes throughout their aging process. The phase delay of adolescence and phase advance of the elderly seem to be phenomena that are more markedly present in men than in women. Thus, our data, for the first time, provide support that sharply opposes the view that there is a single path toward morningness as a function of age, regardless of gender.


Assuntos
Fatores Etários , Ritmo Circadiano/fisiologia , Desenvolvimento Humano/fisiologia , Fatores Sexuais , Atividades Cotidianas/psicologia , Adolescente , Adulto , Idoso , Análise de Variância , Brasil , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários
8.
Braz. j. med. biol. res ; 47(4): 316-320, 8/4/2014. tab, graf
Artigo em Inglês | LILACS | ID: lil-705771

RESUMO

Chronotype is an established concept designed to identify distinct phase relationships between the expression of circadian rhythms and external synchronizers in humans. Although it has been widely accepted that chronotype is subjected to ontogenetic modulation, there is no consensus on the interaction between age and gender. This study aimed to determine the relationship between age- and gender-related changes in the morningness-eveningness character in a large sample of people. A total of 14,650 volunteers were asked to complete the Brazilian version of the Horne and Östberg chronotype questionnaire. The data demonstrated that, on average, women were more morning-oriented than men until the age of 30 and there were no significant differences between men and women from 30 to 45 years of age. In contrast to the situation observed until the age of 30, women older than 45 years were more evening-oriented than men. These results suggest that the ontogenetic development of the circadian timekeeping system is more plastic in men, as represented by the larger amplitude of chronotype changes throughout their aging process. The phase delay of adolescence and phase advance of the elderly seem to be phenomena that are more markedly present in men than in women. Thus, our data, for the first time, provide support that sharply opposes the view that there is a single path toward morningness as a function of age, regardless of gender.


Assuntos
Humanos , Masculino , Feminino , Adolescente , Adulto , Pessoa de Meia-Idade , Idoso , Fatores Sexuais , Fatores Etários , Ritmo Circadiano/fisiologia , Desenvolvimento Humano/fisiologia , Brasil , Atividades Cotidianas/psicologia , Inquéritos e Questionários , Análise de Variância
9.
Minerva Stomatol ; 63(3): 69-75, 2014 Mar.
Artigo em Inglês, Italiano | MEDLINE | ID: mdl-24632798

RESUMO

AIM: Patients affected by unilateral facial palsy often show partial or complete atrophy of the orbicularis oris. The lower hemilip on the affected side may have partial functional recover due to direct reinnervation stemming from the unaffected side. This explains why atrophy of the paralysed side is sometimes limited. Negative esthetic and functional findings include partial invisibility of the vermillion border due to lip inversion resulting from muscle flaccidity, asymmetry of the lower lip, oral incompetence, and speech and nutrition impairments of variable degree. In this study, we used Coleman lipofilling as a secondary and ancillary procedure to consolidate the results already obtained with dynamic reanimation, specifically aiming to reduce the volumetric loss due to atrophy of the orbicularis oris muscle. METHODS: Eight patients underwent lipofilling to restore volumetric loss due to muscular denervation atrophy. Six of our patients were affected by inveterate facial palsy and one by an acute form of facial palsy. The last patient presented with high-grade bilateral upper lip atrophy due to Moebius syndrome. Two patients underwent a second lipofilling intervention. RESULTS: The esthetic volume increase and the ameliorated lip competence were immediately noticeable after the first lipofilling, to great patient satisfaction. As a result of the variable rate of resorption over time of the grafted fat, it may be advisable to repeat the procedure in some patients to maximize results. CONCLUSION: Lipofilling represents a useful and safe ancillary technique for camouflage of lower lip atrophy in paralysed patients.


Assuntos
Paralisia Facial/patologia , Lábio/cirurgia , Procedimentos de Cirurgia Plástica/métodos , Tecido Adiposo , Atrofia , Estética , Humanos , Injeções , Lábio/inervação , Lábio/patologia , Síndrome de Möbius/patologia , Tamanho do Órgão , Coleta de Tecidos e Órgãos
12.
Int J Oral Maxillofac Surg ; 42(5): 611-4, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23490473

RESUMO

Bisphosphonate-related osteonecrosis of the jaw (BRONJ) is an evolving epidemic. Often the patients are in poor general condition and therefore the aim of surgical treatment is generally limited to pain control and restoration of feeding ability. We present a useful surgical technique for the stabilization of BRONJ-related mandibular fractures, including application of a reconstructive plate. With an extraoral approach, a 2.5-mm reconstructive locking plate is contoured and placed in the plane of dissection, superficial to the platysma. The fracture site is accessed through an intraoral approach, which limits surgery to curettage and rinsing of the surgical site. Since there is no removal of the periosteal support to the residual stumps, the blood supply to the affected mandible is maintained. Avoidance of direct contact of the infected fractured site with the reconstructive plate is another advantage of working in a surgical plane over the platysma muscle. Although fracture healing is not achieved, plate fixation with this technique is stable and painless and patients can easily eat; therefore, patients enjoy a great improvement in their quality of life. We consider this easy and effective procedure to be a reliable palliative solution in these patients.


Assuntos
Osteonecrose da Arcada Osseodentária Associada a Difosfonatos/complicações , Fixação Interna de Fraturas/métodos , Doenças Mandibulares/complicações , Fraturas Mandibulares/cirurgia , Músculos do Pescoço/cirurgia , Placas Ósseas , Curetagem/métodos , Fixação Interna de Fraturas/instrumentação , Humanos , Fraturas Mandibulares/etiologia , Reconstrução Mandibular/instrumentação , Reconstrução Mandibular/métodos , Cuidados Paliativos , Qualidade de Vida , Irrigação Terapêutica/métodos
13.
Ann Chir Plast Esthet ; 58(2): 89-95, 2013 Apr.
Artigo em Francês | MEDLINE | ID: mdl-23313587

RESUMO

INTRODUCTION: The facial paralysis is a non-rare condition that has very disabling functional, morphological and psychological repercussions. The current gold standard in facial reanimation is revascularized re-innervated muscle transfers. MATERIALS AND METHODS: In this paper, we report the results of a new method using the gracilis flap with a double innervation on the masseter motor nerve and the controlateral facial nerve via a sural graft in a single stage intervention, on a series of six patients. RESULTS: No failure was observed. The average delay of a voluntary contraction was 3.8months, and 7.2months for a spontaneous one. Three of the six patients had "excellent" results according to the Terzis and Noah classification, two were classified as "good" and one "average". DISCUSSION: A choice is to be made between a method advocating a natural and spontaneous dynamicity (controlateral facial nerve stimulus) and a method focusing on the quality and quantity of contractions (ipsilateral trijeminal stimulus). In this new technique, we combine the two methods: a free gracilis transfer with a dual innervation on the healthy controlateral facial nerve via a sural graft, on one hand, and a second anastomosis on the ipsilateral masseter nerve, on the other hand. CONCLUSION: This new proposed method seems to be, according to our results, a reliable technique rallying voluntary contraction and emotional smile.


Assuntos
Músculos Faciais/cirurgia , Paralisia Facial/cirurgia , Músculo Masseter/cirurgia , Músculo Esquelético/transplante , Procedimentos de Cirurgia Plástica/métodos , Retalhos Cirúrgicos/inervação , Músculos Faciais/inervação , Músculos Faciais/fisiopatologia , Paralisia Facial/fisiopatologia , Feminino , Humanos , Masculino , Músculo Masseter/inervação , Músculo Masseter/fisiopatologia , Pessoa de Meia-Idade , Contração Muscular , Músculo Esquelético/inervação , Sorriso , Coxa da Perna/cirurgia , Resultado do Tratamento
14.
J Plast Reconstr Aesthet Surg ; 65(10): 1343-9, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22728067

RESUMO

OBJECTIVE: One-stage free-flap facial reanimation may be accomplished by using a gracilis transfer innervated by the masseteric nerve, but this technique does not restore the patient's ability to smile spontaneously. By contrast, the transfer of the latissimus dorsi innervated by the contralateral facial nerve provides the correct nerve stimulus but is limited by variation in the quantity of contraction. The authors propose a new one-stage facial reanimation technique using dual innervation; a gracilis muscle flap is innervated by the masseteric nerve, and supplementary nerve input is provided by a cross-face sural nerve graft anastomosed to the contralateral facial nerve branch. METHODS: Between October 2009 and March 2010, four patients affected by long-standing unilateral facial paralysis received gracilis muscle transfers innervated by both the masseteric nerve and the contralateral facial nerve. RESULTS: All patients recovered voluntary and spontaneous smiling abilities. The recovery time to voluntary flap contraction was 3.8 months, and spontaneous flap contraction was achieved within 7.2 months after surgery. According to Terzis and Noah's five-stage classification of reanimation outcomes, two patients had excellent outcomes and two had good outcomes. CONCLUSIONS: In this preliminary study, the devised double-innervation technique allows to achieve a good grade of flap contraction as well as emotional smiling ability. A wider number of operated patients are needed to confirm those initial findings.


Assuntos
Paralisia Facial/cirurgia , Retalhos de Tecido Biológico/inervação , Transferência de Nervo/métodos , Procedimentos de Cirurgia Plástica/métodos , Músculo Quadríceps/cirurgia , Anastomose Cirúrgica/métodos , Doença Crônica , Estética , Expressão Facial , Músculos Faciais/inervação , Músculos Faciais/fisiologia , Nervo Facial/cirurgia , Paralisia Facial/diagnóstico , Feminino , Sobrevivência de Enxerto , Humanos , Masculino , Músculo Masseter/inervação , Músculo Masseter/cirurgia , Pessoa de Meia-Idade , Músculo Quadríceps/transplante , Recuperação de Função Fisiológica , Medição de Risco , Estudos de Amostragem , Índice de Gravidade de Doença , Nervo Sural/cirurgia , Nervo Sural/transplante , Resultado do Tratamento , Cicatrização/fisiologia
15.
Minerva Stomatol ; 59(5): 299-302, 302-4, 2010 May.
Artigo em Inglês, Italiano | MEDLINE | ID: mdl-20502434

RESUMO

The sinus lift procedure in association with dental implant placement and autologous bone grafting enables clinicians to achieve the prosthetic rehabilitation of the posterior edentulous maxilla, when the vertical height of the atrophic crest is reduced. The most commonly reported intraoperative complication of sinus augmentation is membrane perforation, which may lead to infection, with the risk of graft loss or resorption, and acute or chronic sinusitis. We present a technique for repairing a perforated Schnei-derian membrane with a de-epithelialized fibromucosal graft harvested from the palate of a 50-year-old man. In the postoperative period, no wound infections, sinusitis, or bleeding were observed. This technique allowed good prosthetic rehabilitation 3 months postoperatively. This technical procedure is a quick and easy way to treat this surgical complication, allowing repair of the Schneiderian membrane perforation with autologous tissue, without other surgical accesses or need to modify the existing surgical access. In addition, our procedure causes no patient discomfort or adds significant morbidity, with only a moderate increase in surgical time compared to the planned procedure.


Assuntos
Complicações Intraoperatórias/cirurgia , Mucosa Bucal/transplante , Palato , Seios Paranasais/lesões , Seios Paranasais/cirurgia , Humanos , Masculino , Membranas/lesões , Membranas/cirurgia , Pessoa de Meia-Idade
16.
Int J Oral Maxillofac Surg ; 39(10): 1027-32, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20483563

RESUMO

The authors describe a case of oncogenic osteomalacia due to a mesenchymal phosphaturic tumour in the maxillary sinus. This is a paraneoplastic syndrome in which a tumour produces a peptide hormone-like substance (phosphatonin) that causes a urinary loss of phosphates resulting in a debilitating systemic condition. In this case, the patient experienced muscle stiffness, reduction of muscle tone, loss of weight and pathological fractures. Clinical and radiological examination revealed a tumour in the right maxillary sinus; all other results were negative. The diagnosis following pathology examination was mesenchymal phosphaturic tumour with a haemangiopericytoma-like vascular pattern. Different histological types of mesenchymal tumours can be associated with paraneoplastic syndrome, but their localization in the paranasal sinuses is rare. The correct diagnosis allows the appropriate therapeutic approach, which can lead to an almost immediate resolution of the clinical situation after surgical removal of the neoplasm as in the present case. Oncogenic osteomalacia is rare, particularly in the maxillofacial region, and only a few cases have been reported.


Assuntos
Neoplasias do Seio Maxilar/complicações , Mesenquimoma/complicações , Osteomalacia/etiologia , Síndromes Paraneoplásicas/etiologia , Adulto , Feminino , Fator de Crescimento de Fibroblastos 23 , Fatores de Crescimento de Fibroblastos/análise , Seguimentos , Fraturas Espontâneas/etiologia , Humanos , Hipocalcemia/etiologia , Hipofosfatemia/etiologia , Neoplasias do Seio Maxilar/diagnóstico , Mesenquimoma/diagnóstico , Tono Muscular , Doenças Musculares/etiologia , Fosfatos/urina , Redução de Peso
17.
Braz. j. med. biol. res ; 43(1): 96-99, Jan. 2010. tab
Artigo em Inglês | LILACS | ID: lil-535642

RESUMO

The Period 3 and Clock genes are important components of the mammalian molecular circadian system. Studies have shown association between polymorphisms in these clock genes and circadian phenotypes in different populations. Nevertheless, differences in the pattern of allele frequency and genotyping distribution are systematically observed in studies with different ethnic groups. To investigate and compare the pattern of distribution in a sample of Asian and Caucasian populations living in Brazil, we evaluated two well-studied polymorphisms in the clock genes: a variable number of tandem repeats (VNTR) in PER3 and a single nucleotide polymorphism (SNP) in CLOCK. The aim of this investigation was to search for clues about human evolutionary processes related to circadian rhythms. We selected 109 Asian and 135 Caucasian descendants. The frequencies of the shorter allele (4 repeats) in the PER3 gene and the T allele in the CLOCK gene among Asians (0.86 and 0.84, respectively) were significantly higher than among Caucasians (0.69 and 0.71, respectively). Our results directly confirmed the different distribution of these polymorphisms between the Asian and Caucasian ethnic groups. Given the genetic differences found between groups, two points became evident: first, ethnic variations may have implications for the interpretation of results in circadian rhythm association studies, and second, the question may be raised about which evolutionary conditions shaped these genetic clock variations.


Assuntos
Adulto , Feminino , Humanos , Masculino , Povo Asiático/genética , Proteínas CLOCK/genética , Ritmo Circadiano/genética , População Branca/genética , Variação Genética/genética , Proteínas Circadianas Period/genética , Povo Asiático/etnologia , Brasil , População Branca/etnologia , Frequência do Gene , Genótipo , Repetições Minissatélites/genética , Fenótipo , Polimorfismo de Nucleotídeo Único/genética
18.
Braz J Med Biol Res ; 43(1): 96-9, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19967263

RESUMO

The Period 3 and Clock genes are important components of the mammalian molecular circadian system. Studies have shown association between polymorphisms in these clock genes and circadian phenotypes in different populations. Nevertheless, differences in the pattern of allele frequency and genotyping distribution are systematically observed in studies with different ethnic groups. To investigate and compare the pattern of distribution in a sample of Asian and Caucasian populations living in Brazil, we evaluated two well-studied polymorphisms in the clock genes: a variable number of tandem repeats (VNTR) in PER3 and a single nucleotide polymorphism (SNP) in CLOCK. The aim of this investigation was to search for clues about human evolutionary processes related to circadian rhythms. We selected 109 Asian and 135 Caucasian descendants. The frequencies of the shorter allele (4 repeats) in the PER3 gene and the T allele in the CLOCK gene among Asians (0.86 and 0.84, respectively) were significantly higher than among Caucasians (0.69 and 0.71, respectively). Our results directly confirmed the different distribution of these polymorphisms between the Asian and Caucasian ethnic groups. Given the genetic differences found between groups, two points became evident: first, ethnic variations may have implications for the interpretation of results in circadian rhythm association studies, and second, the question may be raised about which evolutionary conditions shaped these genetic clock variations.


Assuntos
Povo Asiático/genética , Proteínas CLOCK/genética , Ritmo Circadiano/genética , Variação Genética/genética , Proteínas Circadianas Period/genética , População Branca/genética , Adulto , Povo Asiático/etnologia , Brasil , Feminino , Frequência do Gene , Genótipo , Humanos , Masculino , Repetições Minissatélites/genética , Fenótipo , Polimorfismo de Nucleotídeo Único/genética , População Branca/etnologia
19.
Braz J Med Biol Res ; 41(10): 914-9, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18982197

RESUMO

Inter-individual differences in the phase of the endogenous circadian rhythms have been established. Individuals with early circadian phase are called morning types; those with late circadian phase are evening types. The Horne and Ostberg Morningness-Eveningness Questionnaire (MEQ) is the most frequently used to assess individual chronotype. The distribution of MEQ scores is likely to be biased by several fact, ors, such as gender, age, genetic background, latitude, and social habits. The objective of the present study was to determine the effect of different social synchronizers on the sleep/wake cycle of persons with different chronotypes. Volunteers were selected from a total of 1232 UFPR undergraduate students who completed the MEQ. Thirty-two subjects completed the study, including 8 morning types, 8 evening types and 16 intermediate types. Sleep schedules were recorded by actigraphy for 1 week on two occasions: during the school term and during vacation. Sleep onset and offset times, sleep duration, and mid-sleep time for each chronotype group were compared by the Mann-Whitney U-test separately for school term and vacation. School term and vacation data were compared by the Wilcoxon matched-pair test. Morning types showed earlier sleep times and longer sleep duration compared with evening types (23:00 +/- 44 and 508.9 +/- 50.27 vs 01:08 +/- 61.95 and 456.44 +/- 59.08, for the weekdays during vacation). During vacation, the subjects showed later sleep times, except for the morning types, who did not exhibit differences for sleep onset times. The results support the idea that social schedules have an impact on the expression of circadian rhythmicity but this impact depends on the individual chronotype.


Assuntos
Relógios Biológicos/fisiologia , Ritmo Circadiano/fisiologia , Sono/fisiologia , Feminino , Humanos , Masculino , Estatísticas não Paramétricas , Inquéritos e Questionários , Fatores de Tempo , Adulto Jovem
20.
Braz. j. med. biol. res ; 41(10): 914-919, Oct. 2008. graf, tab
Artigo em Inglês | LILACS | ID: lil-496809

RESUMO

Inter-individual differences in the phase of the endogenous circadian rhythms have been established. Individuals with early circadian phase are called morning types; those with late circadian phase are evening types. The Horne and Östberg Morningness-Eveningness Questionnaire (MEQ) is the most frequently used to assess individual chronotype. The distribution of MEQ scores is likely to be biased by several fact, ors, such as gender, age, genetic background, latitude, and social habits. The objective of the present study was to determine the effect of different social synchronizers on the sleep/wake cycle of persons with different chronotypes. Volunteers were selected from a total of 1232 UFPR undergraduate students who completed the MEQ. Thirty-two subjects completed the study, including 8 morning types, 8 evening types and 16 intermediate types. Sleep schedules were recorded by actigraphy for 1 week on two occasions: during the school term and during vacation. Sleep onset and offset times, sleep duration, and mid-sleep time for each chronotype group were compared by the Mann-Whitney U-test separately for school term and vacation. School term and vacation data were compared by the Wilcoxon matched-pair test. Morning types showed earlier sleep times and longer sleep duration compared with evening types (23:00 ± 44 and 508.9 ± 50.27 vs 01:08 ± 61.95 and 456.44 ± 59.08, for the weekdays during vacation). During vacation, the subjects showed later sleep times, except for the morning types, who did not exhibit differences for sleep onset times. The results support the idea that social schedules have an impact on the expression of circadian rhythmicity but this impact depends on the individual chronotype.


Assuntos
Feminino , Humanos , Masculino , Adulto Jovem , Relógios Biológicos/fisiologia , Ritmo Circadiano/fisiologia , Sono/fisiologia , Estatísticas não Paramétricas , Inquéritos e Questionários , Fatores de Tempo , Adulto Jovem
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