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1.
Artigo em Inglês | MEDLINE | ID: mdl-38288851

RESUMO

BACKGROUND: The aim was to evaluate the frequency, clinicopathological features, and HPV status of oropharyngeal squamous cell carcinoma (OP-SCC) and benign HPV-related epithelial lesions of the oropharynx over the last 25 years. Moreover, a literature review was performed to investigate HPV frequency in OP-SCC samples diagnosed in Brazilian Centers. MATERIAL AND METHODS: A cross-sectional study analyzed OP-SCC, squamous papilloma, verruca vulgaris, and condyloma accuminatum, diagnosed from 1997 to 2021. HPV status of OP-SCC was determined by immunohistochemistry and "in situ" hybridization. Bivariate statistics were performed (p≤0.05). For the literature review, MEDLINE/PubMed, Web of Science, EMBASE, and Scopus were searched. Two independent reviewers assessed the studies for eligibility. RESULTS: Cross-sectional: 211 OP-SCC (63.0%) and 124 benign lesions (37.0%) were included. OP-SCC frequency increased gradually over time, whereas benign lesions had steady trends. OP-SCC affected more males (n= 171; 81.0%), though the relative frequency in females rose over time. Smoking (n= 127; 60.2%) was common in OP-SCC. Nineteen OP-SCC (13.0%) were positive for HPV. HPV-positive and HPV-negative tumors had similar clinicopathological features (p>0.05). Benign lesions predominated in middle-aged (n= 32; 26.7%) women (n= 71; 57.3%), in the soft palate (n=101; 81.5%). LITERATURE REVIEW: 32 studies were included, and in 60% of them, HPV frequency in OP-SCC was less than 25%. CONCLUSIONS: OP-SCC prevalence has been increasing, and it was mostly associated with smoking and alcohol rather than with HPV infection in Brazil. Benign lesions had a stationary frequency over the evaluated period.

3.
Med Oral Patol Oral Cir Bucal ; 28(6): e512-e518, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37823302

RESUMO

BACKGROUND: Oral Lichen Planus is a potential malignant disorder and shares clinical and histopathological features with other similar lesions. ALDH1 is a specific biomarker for stem cells identification, however its role in stromal cells of immune inflammatory infiltrate has not been explored. The aim of this study was to investigate the ALDH1 immunoexpression in epithelial and stromal cells of Oral Lichen Planus and other lesions with lichenoid inflammatory infiltrate. MATERIAL AND METHODS: 64 samples of Oral Lichen Planus, Oral Lichenoid Lesions, Oral Leukoplakia and Unspecific Chronic Inflammation were included. ALDH1 was evaluated in both epithelium and stromal cells. ALDH1+ cells ≥ 5% were considered positive in epithelium. Stromal cells were evaluated semi quantitatively. Fields were ranked in scores, according to criteria: 1 (0 to 10%); 2 (11 to 50%) and 3 (>50%). The mean value of the sum of the fields was the final score. Statistical differences among groups were investigated, considering p < 0.05. RESULTS: ALDH1 expression in epithelium was low in all groups without difference among them. ALDH1+ cells in the lamina propria were higher for Lichen Planus [2.0], followed by Leukoplakia [1.3], Lichenoid lesions [1.2] and control [1.1] (p<0.05). CONCLUSIONS: ALDH1 immunoexpression in epithelium of lichenoid potential malignant disorders did not show a contributory tool, however ALDH1 in stromal cells of lichen planus might be involved in the complex process of immune regulation associated with the pathogenesis of this disease.


Assuntos
Líquen Plano Bucal , Erupções Liquenoides , Humanos , Líquen Plano Bucal/patologia , Erupções Liquenoides/patologia , Epitélio/patologia , Células Estromais/patologia
4.
Med Oral Patol Oral Cir Bucal ; 28(6): e588-e595, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37471299

RESUMO

BACKGROUND: With the COVID-19 pandemic, there was a need to adopt online teaching methods in a generalized and sudden way, a situation that led to unprecedented changes in the routine of post-graduate students and research development. This study aimed to analyze the evaluation of remote teaching by graduates of master's degrees and advisors in master's programs in the Oral Pathology and Oral Medicine who needed to adapt to a remote teaching methodology in the pandemic. MATERIAL AND METHODS: This quantitative study evaluated the remote teaching in the perception of master's graduates and advisors from postgraduate programs in Oral Pathology and Oral Medicine. Data were collected through an online Google forms® questionnaire. RESULTS: Participated in the study 14 master graduates and 14 master's advisors. Master graduates evaluated that the professors had a good performance (p=0.001), that the duration of the classes was adequate (p=0.015), that the interaction with professors was satisfactory (p=0.007), that they had good interaction with the advisor (p=0.001), that they were satisfied with the remote guidance process (p=0.038) and that face-to-face practical activities were missed (p=0.002). Master's advisors reported satisfaction with remote teaching, good adaptation (p=0.018) and motivation for remote teaching (p=0.016), they evaluated that students were cooperative in activities (p=0.019) and that face-to-face practical activities were missed (p=0.002). CONCLUSIONS: Despite the difficulties, remote teaching proved to be an effective alternative to face-to-face teaching.


Assuntos
COVID-19 , Pandemias , Humanos , Brasil , Patologia Bucal , Inquéritos e Questionários
5.
J Phys Condens Matter ; 32(17): 175403, 2020 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-31935711

RESUMO

This work is devoted to the investigation of nontrivial transport properties in many-body quantum systems. Precisely, we study transport in the steady state of spin-1/2 Heisenberg XXZ chains, driven out of equilibrium by two magnetic baths at their end points. We take graded versions of the model, i.e. asymmetric chains in which some structure gradually changes in space. We investigate how we can manipulate and control the energy and spin currents of such chains by tuning external and/or inner parameters. In particular, we describe the occurrence of energy current rectification and its reversal due to the application of external magnetic fields. We show that, after carefully chosen inner parameters for the system, by turning on an external magnetic field we can find spin and energy currents propagating in different directions. More interestingly, we may find cases in which rectifications of energy and spin currents occur in opposite directions, i.e. if the energy current is larger when flowing from left to right side, then the spin current is larger if it flows from right to left side. We still describe situations with inversion of the energy current direction as we increase the system asymmetry. We stress that our work aims the development of theoretical knowledge as well as the stimulation of future experimental applications.

6.
Phys Rev Lett ; 120(6): 067002, 2018 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-29481286

RESUMO

We study the relationship between the pseudogap and Fermi-surface topology in the two-dimensional Hubbard model by means of the cellular dynamical mean-field theory. We find two possible mean-field metallic solutions on a broad range of interactions, doping, and frustration: a conventional renormalized metal and an unconventional pseudogap metal. At half filling, the conventional metal is more stable and displays an interaction-driven Mott metal-insulator transition. However, for large interactions and small doping, a region that is relevant for cuprates, the pseudogap phase becomes the ground state. By increasing doping, we show that a first-order transition from the pseudogap to the conventional metal is tied to a change of the Fermi surface from hole- to electronlike, unveiling a correlation-driven mechanism for a Lifshitz transition. This explains the puzzling link between the pseudogap phase and Fermi surface topology that has been pointed out in recent experiments.

7.
Virchows Arch ; 471(6): 793-798, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28849259

RESUMO

Polymorphous adenocarcinoma (PAC) is a malignant epithelial neoplasm that affects almost exclusively the minor salivary glands, generally described as having a relatively good prognosis. Aberrant nuclear factor erythroid 2 (NF-E2)-related factor (Nrf2) activation in tumor cells has been associated with induction of antioxidant enzymes, such as peroxiredoxin I (Prx I) and increased matrix metalloproteinase (MMP) expression. In this context, the aim of the present study was to evaluate the expression of Nrf2 and correlate it with Prx I and MMP-2 secretion in PAC. Thirty-one cases of PAC from oral biopsies were selected and immunohistochemically analyzed for Nrf2 and Prx I. MMP-2 quantification was performed on primary cell cultures derived from PAC. Oral squamous cell carcinoma (OSCC) cell cultures were used as control. A high immunoexpression of Nrf2 was observed in both the cytoplasm and the nucleus of neoplastic cells from PAC. Nuclear staining for Nrf2 suggested its activation in the majority of the PAC cells, which was confirmed by the high expression of its target gene, Prx I. Quantification of MMP-2 secretion showed lower levels in PAC cell cultures when compared to OSCC cell cultures (p < 0.05). In conclusion, although Nrf2 overexpression has been frequently associated with high-grade malignancies, such relationship is not infallible and, in fact, the opposite may occur in low-grade tumors, such as PAC of minor salivary glands.


Assuntos
Adenocarcinoma/metabolismo , Metaloproteinase 2 da Matriz/biossíntese , Fator 2 Relacionado a NF-E2/biossíntese , Peroxirredoxinas/biossíntese , Neoplasias das Glândulas Salivares/metabolismo , Glândulas Salivares Menores/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/análise , Feminino , Humanos , Masculino , Metaloproteinase 2 da Matriz/análise , Pessoa de Meia-Idade , Fator 2 Relacionado a NF-E2/análise , Peroxirredoxinas/análise
8.
Phys Rev Lett ; 117(5): 056402, 2016 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-27517782

RESUMO

We present a theoretical investigation of the electronic structure of rutile (metallic) and M_{1} and M_{2} monoclinic (insulating) phases of VO_{2} employing a fully self-consistent combination of density functional theory and embedded dynamical mean field theory calculations. We describe the electronic structure of the metallic and both insulating phases of VO_{2}, and propose a distinct mechanism for the gap opening. We show that Mott physics plays an essential role in all phases of VO_{2}: undimerized vanadium atoms undergo classical Mott transition through local moment formation (in the M_{2} phase), while strong superexchange within V dimers adds significant dynamic intersite correlations, which remove the singularity of self-energy for dimerized V atoms. The resulting transition from rutile to dimerized M_{1} phase is adiabatically connected to the Peierls-like transition, but is better characterized as the Mott transition in the presence of strong intersite exchange. As a consequence of Mott physics, the gap in the dimerized M_{1} phase is temperature dependent. The sole increase of electronic temperature collapses the gap, reminiscent of recent experiments.

9.
J Phys Condens Matter ; 28(19): 195602, 2016 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-27094321

RESUMO

We study the nonequilibrium interplay between disorder and interactions in a closed quantum system. We base our analysis on the notion of dynamical state-space localization, calculated via the Loschmidt echo. Although real-space and state-space localization are independent concepts in general, we show that both perspectives may be directly connected through a specific choice of initial states, namely, maximally localized states (ML-states). We show numerically that in the noninteracting case the average echo is found to be monotonically increasing with increasing disorder; these results are in agreement with an analytical evaluation in the single particle case in which the echo is found to be inversely proportional to the localization length. We also show that for interacting systems, the length scale under which equilibration may occur is upper bounded and such bound is smaller the greater the average echo of ML-states. When disorder and interactions, both being localization mechanisms, are simultaneously at play the echo features a non-monotonic behaviour indicating a non-trivial interplay of the two processes. This interplay induces delocalization of the dynamics which is accompanied by delocalization in real-space. This non-monotonic behaviour is also present in the effective integrability which we show by evaluating the gap statistics.

10.
Phys Rev Lett ; 110(6): 066401, 2013 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-23432281

RESUMO

We present a large N solution of a microscopic model describing the Mott-Anderson transition on a finite-coordination Bethe lattice. Our results demonstrate that strong spatial fluctuations, due to Anderson localization effects, dramatically modify the quantum critical behavior near disordered Mott transitions. The leading critical behavior of quasiparticle wave functions is shown to assume a universal form in the full range from weak to strong disorder, in contrast to disorder-driven non-Fermi liquid ("electronic Griffiths phase") behavior, which is found only in the strongly correlated regime.

11.
Int J Oral Maxillofac Surg ; 41(6): 768-73, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22446071

RESUMO

This study describes the oral and maxillofacial pathological characteristics of a series of odontogenic tumours in children and adolescents from three Brazilian reference centres. The records were reviewed for all odontogenic tumours in patients up to 18 years old based on criteria proposed by the World Health Organization (WHO) in 2005. Data concerning sex, age, skin colour and tumour location were collected and plotted. Four hundred and thirty one odontogenic tumours in children and adolescents were found, accounting for 37.5% of the total number of odontogenic tumours diagnosed. Benign tumours were predominant (99.8% of the cases), and odontoma was the most frequent type (41.4%), followed by keratocystic odontogenic tumours (25.5%) and ameloblastoma (14.6%). Odontogenic tumours were rarely detected in early childhood, and their prevalence increased with age. An almost equal distribution was observed with respect to sex and the site of the lesions. This study is the largest reported retrospective analysis describing odontogenic tumours in children and adolescents to date. The authors detected some variation in the relative frequency of odontogenic tumours compared with similar reports. Additional studies should be conducted based on the new WHO classification and predetermined age parameters to enable comparative analysis among different worldwide populations.


Assuntos
Tumores Odontogênicos/epidemiologia , Adolescente , Fatores Etários , Ameloblastoma/epidemiologia , Brasil/epidemiologia , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Humanos , Lactente , Masculino , Neoplasias Mandibulares/epidemiologia , Neoplasias Maxilares/epidemiologia , Odontoma/epidemiologia , Prevalência , Estudos Retrospectivos , Fatores Sexuais
12.
Braz J Biol ; 70(3): 459-63, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20730334

RESUMO

There is much evidence to support that Mocis latipes larvae (Guenèe, 1852) are the most dangerous pasture pest and usually cause large environmental losses. However, no studies have been carried out to identify the instars during which this moth causes the most damage to the environment. Here we calculate M. latipes larval energy budget to assess its consumption across all instars and estimate the consumption/amount of plant biomass required to complete its larval development. Assimilation, respiration, consumption, excretion, gross growth efficiency and net growth efficiency were calculated. Pearson correlations were used to identify the best predictors that influenced larval growth and weight. Across all instars consumption increased exponentially, especially during the last phase. M. latipes larvae consumed ca 13.8% of total food from the first to the fifth instar, whereas during the sixth instars these larvae consumed ca 72.6%. Results also show that the best gross growth and net growth efficiency were obtained when larvae reached the fifth instar. The results also show that one larva of Mocis latipes consumes 1.02 g (dry weight) of Paspalum maritimum (Trin) in 19 days. Overall, our results indentified the sixth instar as the most destructive instar of this insect. Thus, once we know the most destructive instars of this pest, measures can be taken to disable M. latipes larval development and consequently stop their increase in plant consumption, reducing ecological and economic damage. This knowledge may eventually lead to reduced agricultural damage and contribute to sustainable farming strategies.


Assuntos
Estágios do Ciclo de Vida/fisiologia , Mariposas/crescimento & desenvolvimento , Agricultura , Animais , Comportamento Excretor Animal/fisiologia , Comportamento Alimentar/fisiologia , Feminino , Larva/crescimento & desenvolvimento , Larva/fisiologia , Masculino , Mariposas/classificação , Mariposas/fisiologia
13.
Braz. j. biol ; 70(3): 459-463, Aug. 2010. ilus, tab
Artigo em Inglês | LILACS | ID: lil-555259

RESUMO

There is much evidence to support that Mocis latipes larvae (Guenèe, 1852) are the most dangerous pasture pest and usually cause large environmental losses. However, no studies have been carried out to identify the instars during which this moth causes the most damage to the environment. Here we calculate M. latipes larval energy budget to assess its consumption across all instars and estimate the consumption/amount of plant biomass required to complete its larval development. Assimilation, respiration, consumption, excretion, gross growth efficiency and net growth efficiency were calculated. Pearson correlations were used to identify the best predictors that influenced larval growth and weight. Across all instars consumption increased exponentially, especially during the last phase. M. latipes larvae consumed ca 13.8 percent of total food from the first to the fifth instar, whereas during the sixth instars these larvae consumed ca 72.6 percent. Results also show that the best gross growth and net growth efficiency were obtained when larvae reached the fifth instar. The results also show that one larva of Mocis latipes consumes 1.02 g (dry weight) of Paspalum maritimum (Trin) in 19 days. Overall, our results indentified the sixth instar as the most destructive instar of this insect. Thus, once we know the most destructive instars of this pest, measures can be taken to disable M. latipes larval development and consequently stop their increase in plant consumption, reducing ecological and economic damage. This knowledge may eventually lead to reduced agricultural damage and contribute to sustainable farming strategies.


Inúmeras evidências indicam a larva de Mocis latipes (Guenèe, 1852) como uma das pragas de pastagem mais perigosas e que comumente causam grandes perdas ambientais. Entretanto, nenhum estudo foi feito para identificar qual a fase de desenvolvimento em que o dano ao ambiente é maior. Neste trabalho, nós calculamos o balanço energético larval de M. latipes para descobrir o consumo em cada instar e estimar o consumo requerido para completar o desenvolvimento larval. A assimilação, respiração, excreção, consumo e os coeficientes, bruto e líquido, do crescimento foram calculados. Correlações de Pearson foram usadas para identificar os preditores que mais influenciavam o crescimento da larva. Resultados indicaram que o consumo aumentou exponencialmente durante os instares, especialmente durante o último instar. Larvas de M. latipes consumiram aproximadamente 13,8 por cento do recurso alimentar total entre o primeiro e o quinto instar, enquanto que no sexto instar consumiram 72,6 por cento. Os resultados também indicaram que o consumo bruto e o consumo líquido foram maiores nos últimos instares. Também se verificou que apenas uma larva consumiu 1,02 g de Paspalum maritimum (Poaceae) em 19 dias. Em resumo, nossos resultados identificaram o sexto instar como o mais destrutivo. Uma vez que se conheça o instar mais destrutivo, medidas mais eficazes podem ser tomadas para inibir o desenvolvimento larval de M. Latipes e o crescimento significativo do seu consumo e, consequentemente, reduzir danos ao ambiente. Este conhecimento pode, eventualmente, contribuir para reduzir danos à agricultura e contribuir para seu desenvolvimento sustentável.


Assuntos
Animais , Feminino , Masculino , Estágios do Ciclo de Vida/fisiologia , Mariposas/crescimento & desenvolvimento , Agricultura , Comportamento Excretor Animal/fisiologia , Comportamento Alimentar/fisiologia , Larva/crescimento & desenvolvimento , Larva/fisiologia , Mariposas/classificação , Mariposas/fisiologia
14.
Braz J Biol ; 69(3): 879-85, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19802448

RESUMO

The length-weight relationship and condition factor have been broadly investigated in snails to obtain the index of physical condition of populations and evaluate habitat quality. Herein, our goal was to describe the best predictors that explain Achatina fulica biometrical parameters and well being in a recently introduced population. From November 2001 to November 2002, monthly snail samples were collected in Lauro de Freitas City, Bahia, Brazil. Shell length and total weight were measured in the laboratory and the potential curve and condition factor were calculated. Five environmental variables were considered: temperature range, mean temperature, humidity, precipitation and human density. Multiple regressions were used to generate models including multiple predictors, via model selection approach, and then ranked with AIC criteria. Partial regressions were used to obtain the separated coefficients of determination of climate and human density models. A total of 1.460 individuals were collected, presenting a shell length range between 4.8 to 102.5 mm (mean: 42.18 mm). The relationship between total length and total weight revealed that Achatina fulica presented a negative allometric growth. Simple regression indicated that humidity has a significant influence on A. fulica total length and weight. Temperature range was the main variable that influenced the condition factor. Multiple regressions showed that climatic and human variables explain a small proportion of the variance in shell length and total weight, but may explain up to 55.7% of the condition factor variance. Consequently, we believe that the well being and biometric parameters of A. fulica can be influenced by climatic and human density factors.


Assuntos
Ecossistema , Caramujos/crescimento & desenvolvimento , Animais , Biometria , Brasil , Humanos , Umidade , Densidade Demográfica , Estações do Ano , Caramujos/anatomia & histologia , Temperatura
15.
Braz. j. biol ; 69(3): 879-885, Aug. 2009. graf, mapas, tab
Artigo em Inglês | LILACS | ID: lil-527157

RESUMO

The length-weight relationship and condition factor have been broadly investigated in snails to obtain the index of physical condition of populations and evaluate habitat quality. Herein, our goal was to describe the best predictors that explain Achatina fulica biometrical parameters and well being in a recently introduced population. From November 2001 to November 2002, monthly snail samples were collected in Lauro de Freitas City, Bahia, Brazil. Shell length and total weight were measured in the laboratory and the potential curve and condition factor were calculated. Five environmental variables were considered: temperature range, mean temperature, humidity, precipitation and human density. Multiple regressions were used to generate models including multiple predictors, via model selection approach, and then ranked with AIC criteria. Partial regressions were used to obtain the separated coefficients of determination of climate and human density models. A total of 1.460 individuals were collected, presenting a shell length range between 4.8 to 102.5 mm (mean: 42.18 mm). The relationship between total length and total weight revealed that Achatina fulica presented a negative allometric growth. Simple regression indicated that humidity has a significant influence on A. fulica total length and weight. Temperature range was the main variable that influenced the condition factor. Multiple regressions showed that climatic and human variables explain a small proportion of the variance in shell length and total weight, but may explain up to 55.7 percent of the condition factor variance. Consequently, we believe that the well being and biometric parameters of A. fulica can be influenced by climatic and human density factors.


A relação peso comprimento e o fator de condição têm sido bastante explorados em pesquisas envolvendo caracóis para obter o índice de condição física em populações e avaliar a condição do habitat. Neste trabalho, nosso objetivo foi descrever que variáveis influenciam os parâmteros biométricos e o bem estar de Achatina fulica em uma recente introdução. De novembro de 2001 a novembro de 2002, amostras mensais desses caracóis foram coletadas na cidade de Lauro de Freitas (Bahia), Brasil. Em seguida, os caracóis foram acondicionados em laboratório e foram obtidos o tamanho da concha e o seu peso. A partir desses dados a curva potencial e o fator de condição foram calculados. Cinco variáveis ambientais foram consideradas: amplitude de temperatura, temperatura média, humidade, precipitação e densidade humana. Regressões múltiplas foram usadas para gerar modelos preditivos através do critério de seleção e logo foram ordenados utilizando o critério de Akaíke. Regressões parciais foram usadas para obter os coeficientes de determinação do clima e fatores humanos. Um total de 1460 indivíduos foram coletados, apresentando uma amplitude de crescimento de concha entre 4,9 a 102,5 mm (média 42,18 mm). A relação entre o crescimento total e o peso revelou que A. fulica apresentou um crescimento alométrico negativo. Regressões simples indicaram que a umidade teve uma influencia significativa sobre o tamanho total e o peso. A amplitude de temperatura foi a variável que mais influenciou o fator de condição. Os modelos de regressão múltipla indicaram que os fatores climáticos e humanos explicaram uma pequena porção da variança, no entanto explicou 55,8 por cento da variância do fator de condição. Consequentemente, acreditamos que o bem estar e os parâmetros biométricos de A. Fulica podem ser influenciados por fatores climáticos e humanos.


Assuntos
Animais , Humanos , Ecossistema , Caramujos/crescimento & desenvolvimento , Biometria , Brasil , Umidade , Densidade Demográfica , Estações do Ano , Caramujos/anatomia & histologia , Temperatura
16.
Phys Rev Lett ; 102(15): 156402, 2009 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-19518658

RESUMO

We present a detailed analysis of the critical behavior close to the Mott-Anderson transition. Our findings are based on a combination of numerical and analytical results obtained within the framework of typical-medium theory-the simplest extension of dynamical mean field theory capable of incorporating Anderson localization effects. By making use of previous scaling studies of Anderson impurity models close to the metal-insulator transition, we solve this problem analytically and reveal the dependence of the critical behavior on the particle-hole symmetry. Our main result is that, for sufficiently strong disorder, the Mott-Anderson transition is characterized by a precisely defined two-fluid behavior, in which only a fraction of the electrons undergo a "site selective" Mott localization; the rest become Anderson-localized quasiparticles.

17.
Braz. j. biol ; 68(4): 837-842, Nov. 2008. ilus, graf, mapas, tab
Artigo em Inglês | LILACS | ID: lil-504503

RESUMO

The goal of this study was to document the distribution and establishment A. fulica such as their feeding preference and behavior in situ. The study was carried out at the city of Lauro de Freitas, Bahia state, Brazil, between November 2001 and November 2002. We used catch per unit effort methods to determine abundance, distribution, habitat choice and food preferences. The abundance and distribution of A. fulica was most representative in urban area, mainly near to the coastline. Lots and house gardens were the most preferred sites during active hours. The results indicated that A. fulica started their activity at the end of the evening and stopped in mid-morning. Their preferred food were vascular plants such as Hibiscus syriacus, Ricinus communis, Carica papaya, Galinsonga coccinea, Lippia alba, Ixora coccinea, Musa parasidisiaca, Mentha spicata and Cymbopogon citrates. Our results indicate that A. fulica are well adapted and established in this city and modified environments facilitate their establishment and dispersion. However, human perturbation, such as clearance of lots could be limiting for the persistence of A. fulica populations.


O objetivo deste estudo foi documentar a distribuição e o estabelecimento de Achatina fulica, assim como sua preferência alimentar e aspectos comportamentais in situ. Esta pesquisa foi desenvolvida na cidade de Lauro de Freitas, Estado da Bahia, Brasil, durante os meses de novembro de 2001 a novembro de 2002. Usamos o método de esforço de captura determinado por homem/hora para calcular a abundância e distribuição, habitats preferidos, além de preferência alimentar. Vimos que a abundância e distribuição de A. fulica foram mais representativas em áreas urbanas, sobretudo cerca da linha de costa. Os terrenos e jardins de casas foram os locais preferidos pelos caracóis quando estavam em atividade. Os resultados indicaram que os caracóis A. fulica iniciam sua atividade no final da tarde e hibernam no meio da manhã. A comida preferida destes caracóis foram plantas vasculares como Hibiscus syriacus, Ricinus Communis, Carica papaya, Galinsonga coccinea, Lippia alba, Ixora coccinea, Musa parasidisiaca, Mentha spicata and Cymbopogon citrates. Nossos dados sugerem que o A. fulica está plenamente adaptado e estabelecido nesta cidade e, também, que ambientes modificados facilitam seu estabelecimento e dispersão. Entretanto, a perturbação humana, como a limpeza de terrenos pode ser um fator limitante para a persistência da população de A. fulica.


Assuntos
Animais , Comportamento Alimentar/fisiologia , Caramujos/fisiologia , Brasil , Densidade Demográfica , Dinâmica Populacional , Estações do Ano
18.
Minerva Stomatol ; 57(9): 453-7, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18923380

RESUMO

Mucoepidermoid carcinomas (MECs) are the most common malignancy of the salivary glands demonstrating a wide range of histologic variants and behavior. However, the sclerosing mucoepidermoid carcinoma (SMEC), a morphologic variant of this tumor is extremely rare and has been described almost exclusively in the major glands. The prominent sclerosis observed may obscure its typical morphological feature resulting in a diagnostic challenge. We describe herein a case of SMEC in a 43-year-old-woman, occurring in the minor salivary glands of palate. To our knowledge only 13 cases have been reported until this moment, being only 2 in minor salivary glands. We also performed the immunohistochemical evaluation of c-erbB-2 and Ki-67, searching for an association with the histopathological findings and behavior.


Assuntos
Carcinoma Mucoepidermoide/patologia , Neoplasias das Glândulas Salivares/patologia , Glândulas Salivares Menores , Adulto , Feminino , Humanos , Imuno-Histoquímica
19.
Minerva Stomatol ; 57(1-2): 59-63, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18427372

RESUMO

Inflammatory myofibroblastic tumor is a rare lesion composed of myofibroblastic spindle cells accompanied by inflammatory infiltrate. The objective of this paper is to report an uncommon case of inflammatory myofibroblastic tumor located in the alveolar mucosa of the mandible. A 33-year-old male presented an asymptomatic tumoral lesion, firm, pedunculated, pink-colored, covered by smooth mucosa, with focal ulceration, measuring 30x20x20 mm, located in the left posterior alveolar mucosa. Clinical diagnosis was soft tissue tumor. An excisional biopsy was made. Microscopic examination showed compact fascicular spindle cells proliferation with a diffuse inflammatory infiltrate of plasma cells, lymphocytes, and eosinophils. Large ganglion-like cells were observed. The lesional cells were immunopos-itive to vimentin, a-smooth muscle actin, muscle specific actin, and CD68. Negative immunostain was observed to S-100, Bcl-2, Ki-67, desmin, CD34, and cytokeratin. A diagnosis of inflammatory myofibroblastic tumor was performed. After 28 months of follow-up there was no recurrence. Although no evidence of oral inflammatory myofibroblastic tumor recurrence or malignant transformation has been reported, it has been observed that in inflammatory myofibroblastic tumor of other regions a prolonged follow-up is necessary after surgical excision.


Assuntos
Mucosa Bucal , Neoplasias Bucais/patologia , Neoplasias de Tecido Muscular/patologia , Adulto , Humanos , Masculino , Mandíbula
20.
Minerva Stomatol ; 57(1-2): 65-9, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18427373

RESUMO

RESULTS: Treatment of patients with osteoradionecrosis (ORN) of the mandible associated with pathologic fractures usually consists of a continuity resection of the mandible, leading to severe impairment of the patient's health and quality of life. Conservative treatment may be alternatively attempted; however, it is not usually employed. Here, we report a successful conservative treatment of ORN associated with pathologic fracture. A 48-year-old black man who had undergone radiotherapy for a squamous cell carcinoma in the tongue 6 years previously sought care complaining of facial swelling and draining episodes. Since the patient was fiercely resistant to any kind of hospital-based therapy, a conservative approach was proposed. Daily irrigations with 2% potassium iodate, followed by 3% oxygenated water, were performed by the patient at his house. In addition, local cleaning and debridement were weekly performed at our dental clinic. Systemic antibiotics were also administered. Throughout the therapy course, bone fragments were spontaneously exfoliated. Resolution of the ulcer and fracture was observed after 6 weeks of treatment. This report shows that ORN may be conservatively managed in specific situations, with good cosmetic and functional


Assuntos
Fraturas Espontâneas/etiologia , Doenças Mandibulares/complicações , Doenças Mandibulares/terapia , Fraturas Mandibulares/etiologia , Osteorradionecrose/complicações , Osteorradionecrose/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Indução de Remissão
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