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Plague is a deadly zoonosis that still poses a threat in many regions of the world. We combined epidemiologic, host, and vector surveillance data collected during 1961-1980 from the Araripe Plateau focus in northeastern Brazil with ecologic, geoclimatic, and Yersinia pestis genomic information to elucidate how these factors interplay in plague activity. We identified well-delimited plague hotspots showing elevated plague risk in low-altitude areas near the foothills of the plateau's concave sectors. Those locations exhibited distinct precipitation and vegetation coverage patterns compared with the surrounding areas. We noted a seasonal effect on plague activity, and human cases linearly correlated with precipitation and rodent and flea Y. pestis positivity rates. Genomic characterization of Y. pestis strains revealed a foundational strain capable of evolving into distinct genetic variants, each linked to temporally and spatially constrained plague outbreaks. These data could identify risk areas and improve surveillance in other plague foci within the Caatinga biome.
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Peste , Yersinia pestis , Peste/epidemiologia , Peste/microbiologia , Brasil/epidemiologia , Yersinia pestis/genética , Humanos , Animais , Epidemias , Sifonápteros/microbiologia , Genoma Bacteriano , Genômica/métodos , Estações do AnoRESUMO
Florid osseous dysplasia (FOD) has been described as a condition that typically affects the jaws of middle-aged women of African descent and usually presents as multiple radiopaque masses distributed throughout the jaws. The diagnosis is generally based on clinical and radiographic presentation, often involving various regions of the jaws without evident bone expansion. This article describes the course of FOD in a 27-year-old African-American woman during 22 years of follow-up, emphasizing the dynamic radiographic characteristics of this entity and unusual co-occurrence with multiple simple bone cysts. These data reinforce the importance of long-term follow-up in patients diagnosed with FOD.
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Cistos Ósseos/patologia , Displasia Fibrosa Óssea/patologia , Mandíbula/patologia , Osteomielite/patologia , Adulto , Cistos Ósseos/complicações , Cistos Ósseos/diagnóstico , Progressão da Doença , Feminino , Displasia Fibrosa Óssea/complicações , Displasia Fibrosa Óssea/diagnóstico , Displasia Fibrosa Óssea/diagnóstico por imagem , Humanos , Mandíbula/diagnóstico por imagem , Osteomielite/complicações , Osteomielite/diagnóstico , Osteomielite/diagnóstico por imagem , Radiografia PanorâmicaRESUMO
REVIEW: The pain that commonly occurs after brachial plexus avulsion poses an additional burden on the quality of life of patients already impaired by motor, sensory and autonomic deficits. Evidence-based treatments for the pain associated with brachial plexus avulsion are scarce, thus frequently leaving the condition refractory to treatment with the standard methods used to manage neuropathic pain. Unfortunately, little is known about the pathophysiology of brachial plexus avulsion. Available evidence indicates that besides primary nerve root injury, central lesions related to the abrupt disconnection of nerve roots from the spinal cord may play an important role in the genesis of neuropathic pain in these patients and may explain in part its refractoriness to treatment. CONCLUSIONS: The understanding of both central and peripheral mechanisms that contribute to the development of pain is of major importance in order to propose more effective treatments for brachial plexus avulsion-related pain. This review focuses on the current understanding about the occurrence of neuropathic pain in these patients and the role played by peripheral and central mechanisms that provides insights into its treatment. Pain after brachial plexus avulsion involves both peripheral and central components; thereby it is characterized as a mixed (central and peripheral) neuropathic pain syndrome.
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Neuropatias do Plexo Braquial/etiologia , Plexo Braquial/lesões , Neuralgia/etiologia , Neuropatias do Plexo Braquial/complicações , HumanosRESUMO
OBJECTIVE: To review the literature on the analgesic effects of repetitive transcranial magnetic stimulation (rTMS) in chronic pain according to different pain syndromes and stimulation parameters. DATA SOURCES: Publications on rTMS and chronic pain were searched in PubMed and Google Scholar using the following key words: chronic pain, analgesia, transcranial magnetic stimulation, neuropathic pain, fibromyalgia, and complex regional pain syndrome. STUDY SELECTION: This review only included double-blind, controlled studies with >10 participants in each arm that were published from 1996 to 2014 and written in English. Studies with relevant information for the understanding of the effects of rTMS were also cited. DATA EXTRACTION: The following data were retained: type of pain syndrome, type of study, coil type, target, stimulation intensity, frequency, number of pulses, orientation of induced current, number of session, and a brief summary of intervention outcomes. DATA SYNTHESIS: A total of 33 randomized trials were found. Many studies reported significant pain relief by rTMS, especially high-frequency stimulation over the primary motor cortex performed in consecutive treatment sessions. Pain relief was frequently >30% compared with control treatment. Neuropathic pain, fibromyalgia, and complex regional pain syndrome were the pain syndromes more frequently studied. However, among all published studies, only a few performed repetitive sessions of rTMS. CONCLUSIONS: rTMS has potential utility in the management of chronic pain; however, studies using maintenance sessions of rTMS and assessing the effects of rTMS on the different aspects of chronic pain are needed to provide a more solid basis for its clinical application for pain relief.
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Dor Crônica/reabilitação , Estimulação Magnética Transcraniana/métodos , Síndromes da Dor Regional Complexa/reabilitação , Fibromialgia/reabilitação , Humanos , Córtex Motor , Neuralgia/reabilitação , Modalidades de FisioterapiaRESUMO
Yersinia pestis, the etiological agent of the plague, is considered a genetically homogeneous species. Brazil is currently in a period of epidemiological silence but plague antibodies are still detected in sentinel animals, suggesting disease activity in the sylvatic cycle. The present study deployed an in silico approach to analyze virulence factors among 407 Brazilian genomes of Y. pestis belonging to the Fiocruz Collection (1966-1997). The pangenome analysis associated several known virulence factors of Y. pestis in clades according to the presence or absence of genes. Four main strain clades (C, E, G, and H) exhibited the absence of various virulence genes. Notably, clade G displayed the highest number of absent genes, while clade E showed a significant absence of genes related to the T6SS secretion system and clade H predominantly demonstrated the absence of plasmid-related genes. These results suggest attenuation of virulence in these strains over time. The cgMLST analysis associated genomic and epidemiological data highlighting evolutionary patterns related to the isolation years and outbreaks of Y. pestis in Brazil. Thus, the results contribute to the understanding of the genetic diversity and virulence within Y. pestis and the potential for utilizing genomic data in epidemiological investigations.
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Burnout is a syndrome consisting of physical, emotional, and mental exhaustion along with depersonalization and poor sense of personal accomplishment. Often related to work conditions. Several recent studies from around the world have shown high rates of burnout among medical students in different countries. In Guatemala City, we decided to assess levels of burnout in 2017 and then again in December 2020. In the first wave from one private medical school, we had a total of 159 respondents (response rate of 56.7%) and 132 (48.5%) in the second wave. Not surprisingly rates of burnout were higher during the pandemic even though response rate is lower. Surprisingly we found that rates of depersonalization had not increased, and levels of personal accomplishment had. These findings present a mixed picture of levels of burnout in Guatemala City. Further qualitative research is indicated to explore cultural differences in order to set up appropriate and suitable intervention strategies.
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Esgotamento Profissional , COVID-19 , Estudantes de Medicina , Esgotamento Profissional/epidemiologia , Esgotamento Profissional/psicologia , Esgotamento Psicológico , COVID-19/epidemiologia , Guatemala/epidemiologia , Humanos , Pandemias , Prevalência , Estudantes de Medicina/psicologia , Inquéritos e QuestionáriosRESUMO
Background: Oral mucositis (OM) is one of the most important acute toxicities from radiotherapy (RT) in head and neck cancer patients and can impair oncologic treatment. Dysphagia, dysgeusia, pain, and oral candidiasis are other common toxicities. Brazilian Organic Propolis (BOP) is a recently described propolis variant and BOP types 4 and 6 have shown important antioxidant, anti-inflammatory, and antifungal properties. Purpose: To investigate the use of BOP as a preventive and/or complementary therapeutic option for radiotherapy-induced oral mucositis, dysphagia, dysgeusia, pain, and oral candidiasis. Additionally, proinflammatory cytokines were assessed to investigate their anti-inflammatory role. Methods: Sixty patients were included in this randomized, double-blind, controlled clinical trial. Patients were randomized to receive either aqueous suspension of a BOP or placebo throughout RT. Also, all patients underwent low-level laser therapy as routine oral care. OM, dysphagia, and dysgeusia were assessed weekly according to WHO and NCI scales. Pain-related to OM was assessed according to a Visual Analog Scale and the presence or absence of oral candidiasis was checked by intraoral examination. Protein levels of TNF-α and IL-1ß from oral mucosa were assessed by ELISA. Results: Patients in the propolis group had a lower mean score of OM, dysphagia, dysgeusia, and most patients reported moderate pain. Fewer patients developed oral candidiasis in the propolis group, and the number of episodes was lower among patients that used BOP (p < 0.05). In addition, the BOP group presented significantly lower levels of IL-1ß since the beginning of treatment when compared with placebo patients (p < 0.05) and a lower level of TNF-α at the end of treatment (p < 0.001). Conclusion: Topic use of BOP reduced TNF-α and IL-1ß levels, oral candidiasis episodes, and seems to be a useful complementary option for the prevention and treatment of the main acute oral toxicities of RT. Clinical Trial Registration: http://www.ensaiosclinicos.gov.br/rg/RBR-9f8c78/, identifier RBR-9f8c78.
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Central post-stroke pain affects up to 12% of stroke survivors and is notoriously refractory to treatment. However, stroke patients often suffer from other types of pain of non-neuropathic nature (musculoskeletal, inflammatory, complex regional) and no head-to-head comparison of their respective clinical and somatosensory profiles has been performed so far. We compared 39 patients with definite central neuropathic post-stroke pain with two matched control groups: 32 patients with exclusively non-neuropathic pain developed after stroke and 31 stroke patients not complaining of pain. Patients underwent deep phenotyping via a comprehensive assessment including clinical exam, questionnaires and quantitative sensory testing to dissect central post-stroke pain from chronic pain in general and stroke. While central post-stroke pain was mostly located in the face and limbs, non-neuropathic pain was predominantly axial and located in neck, shoulders and knees (P < 0.05). Neuropathic Pain Symptom Inventory clusters burning (82.1%, n = 32, P < 0.001), tingling (66.7%, n = 26, P < 0.001) and evoked by cold (64.1%, n = 25, P < 0.001) occurred more frequently in central post-stroke pain. Hyperpathia, thermal and mechanical allodynia also occurred more commonly in this group (P < 0.001), which also presented higher levels of deafferentation (P < 0.012) with more asymmetric cold and warm detection thresholds compared with controls. In particular, cold hypoesthesia (considered when the threshold of the affected side was <41% of the contralateral threshold) odds ratio (OR) was 12 (95% CI: 3.8-41.6) for neuropathic pain. Additionally, cold detection threshold/warm detection threshold ratio correlated with the presence of neuropathic pain (ρ = -0.4, P < 0.001). Correlations were found between specific neuropathic pain symptom clusters and quantitative sensory testing: paroxysmal pain with cold (ρ = -0.4; P = 0.008) and heat pain thresholds (ρ = 0.5; P = 0.003), burning pain with mechanical detection (ρ = -0.4; P = 0.015) and mechanical pain thresholds (ρ = -0.4, P < 0.013), evoked pain with mechanical pain threshold (ρ = -0.3; P = 0.047). Logistic regression showed that the combination of cold hypoesthesia on quantitative sensory testing, the Neuropathic Pain Symptom Inventory, and the allodynia intensity on bedside examination explained 77% of the occurrence of neuropathic pain. These findings provide insights into the clinical-psychophysics relationships in central post-stroke pain and may assist more precise distinction of neuropathic from non-neuropathic post-stroke pain in clinical practice and in future trials.
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The plague caused by the Yersinia pestis bacterium is primarily a flea-transmitted zoonosis of rodents that can also be conveyed to humans and other mammals. In this work, we analyzed the spatial and temporal distribution of rodent populations during epizootic and enzootic periods of the plague in the municipality of Exu, northeastern Brazil. The geospatial analyses showed that all the rodent species appeared through the whole territory of the municipality, with different occurrence hotspots for the different species. Important fluctuations in the rodent populations were observed, with a reduction in the wild rodent fauna following the end of a plague epizootic period, mostly represented by Necromys lasiurus and an increase in the commensal species Rattus rattus. A higher abundance of rats might lead to an increased exposure of human populations, favoring spillovers of plague and other rodent-borne diseases. Our analysis highlights the role of wild rodent species as amplifier hosts and of commensal rats (R. rattus) as preserver hosts in the enzootic period of a specific transmission infection area.
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Along with other countries in America, plague reached Brazil through the sea routes during the third pandemic. A brief ports phase was followed by an urban phase that took place in smaller inland cities and finally, it attained the rural area and established several foci where the ecological conditions were suitable for its continued existence. However, the geographic dispersion of plague in Brazil is still poorly studied. To better understand the disease dynamics, we accessed satellite-based data to trace the spatial occurrence and distribution of human plague cases in Pernambuco, Northeastern Brazil and using the municipality of Exu as study case area. Along with the satellite data, a historical survey using the Plague Control Program files was applied to characterize the spatial and temporal dispersion of cases in the period of 1945-1976. Kernel density estimation, spatial and temporal clusters with statistical significance and maximum entropy modeling were used for spatial data analysis, by means of the spatial analysis software packages. The use of geostatistical tools allowed evidencing the shift of the infection from the urban to the wild-sylvatic areas and the reemergence of cases after a period of quiescence, independent of the reintroduction from other plague areas.
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Peste/epidemiologia , Análise Espaço-Temporal , Adulto , Brasil/epidemiologia , Cidades/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
Plague, caused by the Yersinia pestis bacterium, has several foci scattered throughout a large area from the Brazilian territory that ranges from the Northeastern State of Ceará to the Southeastern State of Minas Gerais and another separated area at the State of Rio de Janeiro. This review gathers data from plague control and surveillance programs on the occurrence and geographic distribution of rodent hosts and flea vectors in the Brazilian plague areas during the period of from 1952 to 2019. Furthermore, we discuss how the interaction between Y. pestis and some rodent host species may play a role in the disease dynamics. The absence of human cases nowadays in Brazil does not mean that it was eradicated. The dynamics of plague in Brazil and in other countries where it was introduced during the 3rd pandemic are quite alike, alternating epidemics with decades of quiescence. Hence, it remains an important epidemic disease of global concern. The existence of a large animal reservoir and competent vectors demonstrate a need for continuous surveillance to prevent new outbreaks of this disease in humans.
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Insetos Vetores/microbiologia , Peste/transmissão , Roedores/parasitologia , Sifonápteros/microbiologia , Yersinia pestis/fisiologia , Zoonoses/transmissão , Animais , Brasil/epidemiologia , Humanos , Peste/epidemiologia , Zoonoses/microbiologiaRESUMO
Lapachol is a naturally occurring naphthoquinone derivative found in the heartwood of several plants, particularly those of the genus Tabebuia (Bignoneaceae). Despite its use as a therapeutic product with anti-inflammatory, analgesic, antipsoriatic, trypanocidal effects, among others, its in vivo mutagenic potential has still not been investigated. This paper reports the effects after a single oral administration of lapachol in the in vivo micronucleus (MN) and chromosome aberration (CA) assays. Both assays were performed using bone marrow cells from male Wistar rats. The animals were treated by oral gavage with hydroalcoholic solutions of lapachol at the doses of 122, 244 and 365 mg/kg, chosen on the basis of the LD(50) in male rats. The results show that the higher administered lapachol dose induced a significant increase in the frequency of micronucleated polychromatic erythrocytes (MNPCE) and CAs in rat bone marrow cells, indicating that lapachol shows clastogenic effects under the experimental conditions used.
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Células da Medula Óssea/efeitos dos fármacos , Aberrações Cromossômicas , Eritrócitos/efeitos dos fármacos , Mutagênicos/efeitos adversos , Naftoquinonas/efeitos adversos , Extratos Vegetais/efeitos adversos , Tabebuia/química , Animais , Masculino , Testes para Micronúcleos , Testes de Mutagenicidade , Ratos , Ratos Wistar , MadeiraRESUMO
BACKGROUND: Venous lake lesion is a venous ectasia that can occur on the lips of older people. Although different therapies have been used, there is no guideline for treating this lesion. The purpose of this study was to evaluate whether sclerotherapy is an effective and acceptable option for treatment of venous lake lesions of the lips in older patients. METHODS: Medical records and images were retrieved from the archives of a geriatric dentistry clinic between 2005 and 2017. A total of 33 older patients treated with 5% ethanolamine oleate were included. Clinical information was selected and described. RESULTS: The female gender was predominant (64%), and the patients' age ranged from 66 to 90 years. The majority of the patients were Caucasian (91%), and 82% were under treatment for hypertension. In 91% of the cases, the lesions were located on the lower lip and varied from 3 to 10 mm in diameter. A complaint period lasting longer than 2 years was reported by 58% of the patients. Color alteration was the most common type of esthetic complaint. Only one application of sclerotherapy was performed in 85% of the cases. For the remaining patients, two sessions were necessary. The total dose ranged from 0.3 to 0.9 ml. Complete regression of the lesions was observed in all cases. No complications or recurrences were reported. CONCLUSION: Sclerotherapy with ethanolamine oleate is an effective, affordable, and predictable treatment for venous lake lesions of the lips in older patients.
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OBJECTIVES: Head and neck radiotherapy can cause several toxicities, and its management has important treatment implications. Proper information about treatment is crucial to assist patients by preparing them and enhancing their ability to manage their illness. Thus, this study aimed to verify the impact of an educational video on the improvement of the patient's understanding, satisfaction, quality of life, and influence on their emotional state in different moments of treatment. METHODS: A 10 min video about head and neck radiotherapy and its toxicities was produced. A prospective randomized clinical trial was performed in two groups: a control group (n = 65), which received standard verbal and written information, and an experimental group (n = 65), which received standard information and the video. Appropriated questionnaires (HADS, UW-QOLv4, IRTU, and Post-RTU) were applied in four different moments in order to evaluate patients' understanding, anxiety, depression, and quality of life. RESULTS: The video improved the understanding of treatment and its side effects. Also, the video group reported better awareness about oral health care during the treatment. Osteoradionecrosis and radiation-related caries were the most unknown side effects. On the other hand, the educational video did not modify the patients' anxiety, depression, and quality of life. All patients reported high satisfaction with the video. CONCLUSIONS: Audiovisual tools may improve patients' understanding of radiotherapy and were shown to be a useful tool when used in association with verbal and written information in cancer centers. In addition, information about osteoradionecrosis and radiation-related caries must be reinforced to patients.
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Ansiedade/etiologia , Depressão/etiologia , Neoplasias de Cabeça e Pescoço/complicações , Neoplasias de Cabeça e Pescoço/radioterapia , Qualidade de Vida/psicologia , Lesões por Radiação/diagnóstico , Gravação em Vídeo/métodos , Adulto , Idoso , Feminino , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
Renal transplant patients are treated with immunosuppressive drugs that decrease the effectiveness of the immune system, making them more prone to developing cancer. Skin and lip carcinomas are common malignancies encountered after transplantation, whereas oral carcinomas are rare. We report the case of a 51-year-old female Caucasian patient, with no history of smoking, who presented white lesions on the tongue and an ulcerated lesion on the lower lip beginning 4 months prior. Diagnosis of squamous cell carcinoma for both lesions was made following incisional biopsies. Interestingly, the patient reported a renal transplantation 23 years prior, and was maintained on a combination of cyclosporine, mycophenolate sodium and prednisone. The patient also presented a history of several basal and squamous cell carcinomas on sun-exposed areas of the skin. Both lesions were surgically excised. No sign of recurrence or new lesions in the oral cavity have been observed; however, new skin lesions are frequently diagnosed. This case report highlights that oral cancers may occur in transplant patients in the absence of classical risk factors. Thus, clinicians must be aware of the importance of thorough oral examination in transplant patients in routine follow-up.
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OBJECTIVE: To compare the analgesic effects of stimulation of the anterior cingulate cortex (ACC) or the posterior superior insula (PSI) against sham deep (d) repetitive (r) transcranial magnetic stimulation (TMS) in patients with central neuropathic pain (CNP) after stroke or spinal cord injury in a randomized, double-blinded, sham-controlled, 3-arm parallel study. METHODS: Participants were randomly allocated into the active PSI-rTMS, ACC-rTMS, sham-PSI-rTMS, or sham-ACC-rTMS arms. Stimulations were performed for 12 weeks, and a comprehensive clinical and pain assessment, psychophysics, and cortical excitability measurements were performed at baseline and during treatment. The main outcome of the study was pain intensity (numeric rating scale [NRS]) after the last stimulation session. RESULTS: Ninety-eight patients (age 55.02 ± 12.13 years) completed the study. NRS score was not significantly different between groups at the end of the study. Active rTMS treatments had no significant effects on pain interference with daily activities, pain dimensions, neuropathic pain symptoms, mood, medication use, cortical excitability measurements, or quality of life. Heat pain threshold was significantly increased after treatment in the PSI-dTMS group from baseline (1.58, 95% confidence interval [CI] 0.09-3.06]) compared to sham-dTMS (-1.02, 95% CI -2.10 to 0.04, p = 0.014), and ACC-dTMS caused a significant decrease in anxiety scores (-2.96, 95% CI -4.1 to -1.7]) compared to sham-dTMS (-0.78, 95% CI -1.9 to 0.3; p = 0.018). CONCLUSIONS: ACC- and PSI-dTMS were not different from sham-dTMS for pain relief in CNP despite a significant antinociceptive effect after insular stimulation and anxiolytic effects of ACC-dTMS. These results showed that the different dimensions of pain can be modulated in humans noninvasively by directly stimulating deeper SNC cortical structures without necessarily affecting clinical pain per se. CLINICALTRIALSGOV IDENTIFIER: NCT01932905.
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Córtex Cerebral/fisiopatologia , Estimulação Encefálica Profunda/métodos , Giro do Cíngulo/fisiopatologia , Neuralgia/terapia , Estimulação Magnética Transcraniana/métodos , Adulto , Idoso , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neuralgia/fisiopatologia , Manejo da Dor/métodos , Medição da Dor , Resultado do TratamentoAssuntos
Neoplasias da Língua , Língua , Masculino , Humanos , Criança , Neoplasias da Língua/cirurgiaRESUMO
AIM: Langerhans cell histiocytosis (LCH) is an unusual proliferative disorder of bone marrow-derived histiocytes (Langerhans cells) that can produce focal or systemic manifestations. Oral manifestations of LCH can present as single or multiple lesions and can be a challenge in clinical practice. The aim of this paper is to present the clinicopathological features of a series of nine patients with oral involvement. METHODS AND RESULTS: The patient's age ranged from 2 to 63 years being five males and four females. The most common oral site involvement was the hard-palate mucosa. Ulceration was the main clinical feature. Only two patients showed clearly jawbone involvement. In eight out of nine patients, the diagnosis of LCH was established because of the oral manifestations. CONCLUSION: The recognition of the clinical features of LCH oral manifestation is important to avoid misdiagnosis and to the establishment of the correct treatment. Thus, dentists can play a vital role in the diagnosis of LCH since oral lesions may be the earliest manifestation and sometimes the only sign of the disease. Furthermore, oral lesions may be the early signs of disease reactivation or a multisystem disease indication.
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Histiocitose de Células de Langerhans/complicações , Úlceras Orais/etiologia , Periodontite/etiologia , Adolescente , Adulto , Criança , Pré-Escolar , Diagnóstico Diferencial , Feminino , Histiocitose de Células de Langerhans/patologia , Histiocitose de Células de Langerhans/terapia , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Úlceras Orais/patologia , Úlceras Orais/terapia , Periodontite/patologia , Periodontite/terapiaRESUMO
The circadian system is organized in a hierarchy of multiple oscillators, with the suprachiasmatic nucleus (SCN) as the master oscillator in mammals. The SCN is formed by a group of coupled cell oscillators. Knowledge of this coupling mechanism is essential to understanding entrainment and the expression of circadian rhythms. Some authors suggest that light-dark (LD) cycles with periods near the limit of entrainment may be good models for promoting internal desynchronization, providing knowledge about the coupling mechanism. As such, we evaluated the circadian activity rhythm (CAR) pattern of marmosets in LD cycles at lower limits of entrainment in order to study induced internal dissociation. To that end, two experiments were conducted: (1) 6 adult females were under symmetrical LD cycles T21, T22 and T21.5 for 60, 35 and 48 days, respectively; and (2) 4 male and 4 female adults were under T21 for 24 days followed by 18 days of LL, back to T21 for 24 days, followed by 14 days of LL. The CAR of each animal was continuously recorded. In experiment 1, vocalizations were also recorded. Under Ts shorter than 24 days, a dissociation pattern was observed for CAR and vocalizations. Two simultaneous circadian components emerged, one with the same period as the LD cycle, called the light-entrained component, and the other in free-running, denominated the non-light-entrained component. Both components were displayed in the CAR for all the animals in T21, five animals (83.3%) in T21.5 and two animals (33.3%) in T22. Our results are in accordance with the multioscillatory nature of the circadian system. Dissociation is partial synchronization to the LD cycle, with at least one group of oscillators synchronized by relative coordination and masking, while another group of oscillators free runs, but is also masked by the LD cycle. Since only T21 promoted the emergence of both circadian components in the circadian rhythms of all marmosets, it was considered the promoter period of circadian rhythm dissociation in this species, and is proposed as a good animal model for forced desynchronization in non-human diurnal primates.