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1.
Front Med (Lausanne) ; 11: 1330482, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38774396

RESUMO

Introduction: Given the ensuing increase in bone and periodontal diseases and defects, de novo bone repair and/or regeneration strategies are constantly undergoing-development alongside advances in orthopedic, oro-dental and cranio-maxillo-facial technologies and improvements in bio-/nano-materials. Indeed, there is a remarkably growing need for new oro-dental functional biomaterials that can help recreate soft and hard tissues and restore function and aesthetics of teeth/ dentition and surrounding tissues. In bone tissue engineering, HydroxyApatite minerals (HAp), the most stable CaP/Calcium Phosphate bioceramic and a widely-used material as a bone graft substitute, have been extensively studied for regenerative medicine and dentistry applications, including clinical use. Yet, limitations and challenges owing principally to its bio-mechanical strength, exist and therefore, research and innovation efforts continue to pursue enhancing its bio-effects, particularly at the nano-scale. Methods: Herein, we report on the physico-chemical properties of a novel nanoHydroxyApatite material obtained from the backbone of Salmon fish (patent-pending); an abundant and promising yet under-explored alternative HAp source. Briefly, our nanoS-HAp obtained via a modified and innovative alkaline hydrolysis-calcination process was characterized by X-ray diffraction, electron microscopy, spectroscopy, and a cell viability assay. Results and Discussion: When compared to control HAp (synthetic, human, bovine or porcine), our nanoS-HAp demonstrated attractive characteristics, a promising biomaterial candidate for use in bone tissue engineering, and beyond.

2.
Rev Neurol ; 77(8): 185-196, 2023 10 16.
Artigo em Espanhol | MEDLINE | ID: mdl-37807883

RESUMO

INTRODUCTION: Cladophialophora bantiana is a filamentous fungus, known as a dematiaceous fungus because of the presence of melanin. This fungus is of clinical importance because it is neurotropic and causes cerebral phaeohyphomycosis. MATERIAL AND METHODS: The available scientific information on the development of cerebral phaeohyphomycosis caused by Cladophialophora bantiana was analysed by selecting articles from the PubMed, Scopus and Google Scholar databases that describe case reports of fungal infection by C. bantiana in adults, taking into account the analysis of the patients' symptomatology, clinical history and neuroanatomical damage, in addition to considering the mortality of the condition. RESULTS: India and United States were the countries with most case reports, with 32 and 11 cases respectively. Moreover, in terms of neuroanatomical lesions, the majority of patients suffered mixed lesions (29%) and frontal lobe lesions (22%). In accordance with the patients' condition, the pathology has a mortality rate of 62%. CONCLUSIONS: It is concluded that cerebral phaeohyphomycosis has a high mortality rate, there is no standardised treatment and, in most cases, the fungal infection of the brain is mixed and affects several different parts of it. Furthermore, if not diagnosed and treated in time, it can lead to the patients' death.


TITLE: Infección micótica por Cladophialophora bantiana y desarrollo de feohifomicosis cerebral. Revisión sistemática de 58 informes de caso.Introducción. Cladophialophora bantiana es un hongo filamentoso, denominado hongo dematiáceo por la presencia de melanina. Este hongo tiene importancia clínica por ser neurotrópico y causar feohifomicosis cerebral. Material y métodos. Se analizó la información científica disponible sobre el desarrollo de feohifomicosis cerebral provocada por Cladophialophora bantiana, seleccionando artículos de las bases de PubMed, Scopus y Google Scholar, que describen informes de caso sobre infección micótica de C. bantiana en adultos, considerando el análisis de la sintomatología, el historial clínico y los daños neuroanatómicos de los pacientes, además de considerar la mortalidad de la patología. Resultados. La India y Estados Unidos fueron los países con más informes de caso, 32 y 11 casos, respectivamente. Asimismo, en cuanto a las lesiones neuroanatómicas, en su mayoría, los pacientes sufrieron lesiones mixtas (29%) y del lóbulo frontal (22%). De acuerdo con el estado de los pacientes, la patología tiene una mortalidad del 62%. Conclusiones. Se concluye que la feohifomicosis cerebral tiene una alta mortalidad, no existe un tratamiento estandarizado y, en la mayoría de los casos, la infección fúngica del cerebro es mixta y afecta a varias partes del cerebro; además, si no se diagnostica y trata a tiempo, puede ocasionar la muerte de los pacientes.


Assuntos
Ascomicetos , Abscesso Encefálico , Feoifomicose Cerebral , Micoses , Adulto , Humanos , Antifúngicos/uso terapêutico , Abscesso Encefálico/tratamento farmacológico , Feoifomicose Cerebral/diagnóstico , Feoifomicose Cerebral/tratamento farmacológico , Micoses/tratamento farmacológico , Relatos de Casos como Assunto
3.
Mol Biol Rep ; 49(6): 4861-4871, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35334019

RESUMO

BACKGROUND: Open cast mining is well known as a concerning source of environmental and public health problems. This work aimed to obtain a hydroethanolic coal dust extract (≤ 38 µm) and to characterize its composition with particular regard to content of organic compounds by GC/MS, as well as describe its toxicity in vitro on Calu-1 after exposure to several concentrations (0-500 µg/mL). MATERIALS AND RESULTS: Cytotoxicity was measured with MTT assay and DCFH-DA probe was employed to estimate the amount of reactive oxygen species (ROS) in Calu-1 cells. RT-PCR was employed to quantify relative expression of genes associated with inflammation, oxidative stress, as well as metals, and lipid metabolism. Seventeen organic compounds were identified in the extract, highlighting undecane, dodecane, pentadecane and benzo[a]anthracene, 6,12-dimethyl-1,2,3,4-tetrahydro-. Cytotoxicity test showed a decrease trend in the cell viability after 24 h hours from the concentration of 62.5 µg/mL. Further, the extract raised intracellular ROS when compared with control. Expression levels of CYP1A1, IL-8, IL-6, MT1X, and NQO1 were up-regulated when cells were exposed to 125 µg/mL of coal dust, whereas PPAR-α was down-regulated, likely involving aryl hydrocarbon receptor regulation. CONCLUSIONS: In short, this study shows that despite hydroethanolic coal dust extract is not cytotoxic to Calu-1 cells, it produces an elevation of intracellular ROS and alters the expression in marker genes of oxidative stress, inflammation, metal transport, xenobiotic and lipid metabolism. These findings suggest that chemicals present in coal dust are biologically active and may interfere key biochemical process in the living organisms.


Assuntos
Minas de Carvão , Carvão Mineral , Carvão Mineral/análise , Carvão Mineral/toxicidade , Dano ao DNA , Poeira/análise , Humanos , Inflamação/induzido quimicamente , Inflamação/genética , Pulmão , Metais/toxicidade , Estresse Oxidativo , Espécies Reativas de Oxigênio
4.
Molecules ; 25(16)2020 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-32823556

RESUMO

In the current work, flexible diodes with flat heterojunction and dispersed heterojunction architecture were manufactured with to study the behavior of thin films of disodium phthalocyanine (Na2Pc). The thin film devices, using the electronic acceptor tetracyano-π-quinodimethane (TCNQ), were fabricated by high-vacuum thermal evaporation with annealing post-treatment in order to optimize their behavior. Theoretical calculations based on density functional theory (DFT) with dispersion force analysis were carried out in order to simulate molecular interactions and to establish the nature of the weak interactions between the Na2Pc and TCNQ fragments. In the optimized structure of the coupled Na2Pc-TCNQ, the electronic relationship between phthalocyanine and TCNQ was observed to be through hydrogen bonds with bond lengths of 2.94 and 3.13 Å. Dispersed heterojunction device current density values were considerably larger than those of the flat heterojunction device. Barrier heights of 1.024 and 0.909 eV and charge mobilities of 10-10 and 10-9 m2/Vs for the flat heterojunction device and the dispersed heterojunction device, respectively, were observed. A small effect was observed on the electrical properties by thermal annealing on the flat heterojunction device. The threshold voltage decreased from 1.203 to 1.147 V and φb decreased by 0.001 eV.


Assuntos
Condutividade Elétrica , Equipamentos e Provisões Elétricas , Indóis , Fenômenos Mecânicos , Isoindóis , Modelos Moleculares , Conformação Molecular
6.
Braz J Med Biol Res ; 39(1): 9-18, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16400460

RESUMO

Coronary artery disease (CAD) is a worldwide leading cause of death. The standard method for evaluating critical partial occlusions is coronary arteriography, a catheterization technique which is invasive, time consuming, and costly. There are noninvasive approaches for the early detection of CAD. The basis for the noninvasive diagnosis of CAD has been laid in a sequential analysis of the risk factors, and the results of the treadmill test and myocardial perfusion scintigraphy (MPS). Many investigators have demonstrated that the diagnostic applications of MPS are appropriate for patients who have an intermediate likelihood of disease. Although this information is useful, it is only partially utilized in clinical practice due to the difficulty to properly classify the patients. Since the seminal work of Lotfi Zadeh, fuzzy logic has been applied in numerous areas. In the present study, we proposed and tested a model to select patients for MPS based on fuzzy sets theory. A group of 1053 patients was used to develop the model and another group of 1045 patients was used to test it. Receiver operating characteristic curves were used to compare the performance of the fuzzy model against expert physician opinions, and showed that the performance of the fuzzy model was equal or superior to that of the physicians. Therefore, we conclude that the fuzzy model could be a useful tool to assist the general practitioner in the selection of patients for MPS.


Assuntos
Doença da Artéria Coronariana/diagnóstico por imagem , Teste de Esforço , Lógica Fuzzy , Seleção de Pacientes , Adulto , Idoso , Doença da Artéria Coronariana/classificação , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Teóricos , Perfusão , Cintilografia , Fatores de Risco , Sensibilidade e Especificidade , Índice de Gravidade de Doença
7.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;39(1): 9-18, Jan. 2006. tab, graf
Artigo em Inglês | LILACS | ID: lil-419148

RESUMO

Coronary artery disease (CAD) is a worldwide leading cause of death. The standard method for evaluating critical partial occlusions is coronary arteriography, a catheterization technique which is invasive, time consuming, and costly. There are noninvasive approaches for the early detection of CAD. The basis for the noninvasive diagnosis of CAD has been laid in a sequential analysis of the risk factors, and the results of the treadmill test and myocardial perfusion scintigraphy (MPS). Many investigators have demonstrated that the diagnostic applications of MPS are appropriate for patients who have an intermediate likelihood of disease. Although this information is useful, it is only partially utilized in clinical practice due to the difficulty to properly classify the patients. Since the seminal work of Lotfi Zadeh, fuzzy logic has been applied in numerous areas. In the present study, we proposed and tested a model to select patients for MPS based on fuzzy sets theory. A group of 1053 patients was used to develop the model and another group of 1045 patients was used to test it. Receiver operating characteristic curves were used to compare the performance of the fuzzy model against expert physician opinions, and showed that the performance of the fuzzy model was equal or superior to that of the physicians. Therefore, we conclude that the fuzzy model could be a useful tool to assist the general practitioner in the selection of patients for MPS.


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Doença da Artéria Coronariana , Teste de Esforço , Lógica Fuzzy , Seleção de Pacientes , Doença da Artéria Coronariana/classificação , Seguimentos , Modelos Teóricos , Perfusão , Fatores de Risco , Sensibilidade e Especificidade , Índice de Gravidade de Doença
8.
Vet Res Commun ; 29 Suppl 1: 51-9, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15943065

RESUMO

Chlamydophila abortus is the aetiological agent of enzootic abortion in small ruminants in which it infects the placenta to cause abortion during the last trimester of gestation. In a mouse model, a Th1 immune response involving IFN-gamma production and CD8+ T cells is necessary for the infection to be resolved. The authors previously demonstrated that infection with Nippostrongylus brasiliensis, a rodent gastrointestinal nematode extensively used in experimental models to induce Th2 responses, alters the specific immune response against C. abortus infection, increasing bacterial multiplication in liver and reducing specific IFN-gamma production. The aim of the present work was to clarify whether a Th2 immune response has any influence on the success of vaccination using both inactivated and attenuated vaccines. The results showed that the Th2 response established prior to vaccination did not influence the induction of protection offered by the vaccines. However, the effectiveness of this protective response can be altered, depending on the adjuvant employed in the inactivated vaccines, when the Th2 response is established after vaccination, just before challenge with C. abortus.


Assuntos
Vacinas Bacterianas/imunologia , Infecções por Chlamydophila/prevenção & controle , Chlamydophila/imunologia , Nippostrongylus/imunologia , Infecções por Strongylida/imunologia , Células Th2/imunologia , Animais , Células Cultivadas , Infecções por Chlamydophila/complicações , Infecções por Chlamydophila/imunologia , Chlamydophila psittaci/imunologia , Citocinas/metabolismo , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Baço/citologia , Infecções por Strongylida/complicações
9.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;37(5): 755-764, May 2004. ilus, tab, graf
Artigo em Inglês | LILACS | ID: lil-357551

RESUMO

In view of the importance of anticipating the occurrence of critical situations in medicine, we propose the use of a fuzzy expert system to predict the need for advanced neonatal resuscitation efforts in the delivery room. This system relates the maternal medical, obstetric and neonatal characteristics to the clinical conditions of the newborn, providing a risk measurement of need of advanced neonatal resuscitation measures. It is structured as a fuzzy composition developed on the basis of the subjective perception of danger of nine neonatologists facing 61 antenatal and intrapartum clinical situations which provide a degree of association with the risk of occurrence of perinatal asphyxia. The resulting relational matrix describes the association between clinical factors and risk of perinatal asphyxia. Analyzing the inputs of the presence or absence of all 61 clinical factors, the system returns the rate of risk of perinatal asphyxia as output. A prospectively collected series of 304 cases of perinatal care was analyzed to ascertain system performance. The fuzzy expert system presented a sensitivity of 76.5 percent and specificity of 94.8 percent in the identification of the need for advanced neonatal resuscitation measures, considering a cut-off value of 5 on a scale ranging from 0 to 10. The area under the receiver operating characteristic curve was 0.93. The identification of risk situations plays an important role in the planning of health care. These preliminary results encourage us to develop further studies and to refine this model, which is intended to implement an auxiliary system able to help health care staff to make decisions in perinatal care.


Assuntos
Humanos , Feminino , Recém-Nascido , Adolescente , Adulto , Asfixia Neonatal , Sistemas Inteligentes , Lógica Fuzzy , Ressuscitação , Tomada de Decisões , Valor Preditivo dos Testes , Estudos Prospectivos , Fatores de Risco , Sensibilidade e Especificidade
10.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;37(5): 701-709, May 2004. tab, graf
Artigo em Inglês | LILACS | ID: lil-357553

RESUMO

The present study compares the performance of stochastic and fuzzy models for the analysis of the relationship between clinical signs and diagnosis. Data obtained for 153 children concerning diagnosis (pneumonia, other non-pneumonia diseases, absence of disease) and seven clinical signs were divided into two samples, one for analysis and other for validation. The former was used to derive relations by multi-discriminant analysis (MDA) and by fuzzy max-min compositions (fuzzy), and the latter was used to assess the predictions drawn from each type of relation. MDA and fuzzy were closely similar in terms of prediction, with correct allocation of 75.7 to 78.3 percent of patients in the validation sample, and displaying only a single instance of disagreement: a patient with low level of toxemia was mistaken as not diseased by MDA and correctly taken as somehow ill by fuzzy. Concerning relations, each method provided different information, each revealing different aspects of the relations between clinical signs and diagnoses. Both methods agreed on pointing X-ray, dyspnea, and auscultation as better related with pneumonia, but only fuzzy was able to detect relations of heart rate, body temperature, toxemia and respiratory rate with pneumonia. Moreover, only fuzzy was able to detect a relationship between heart rate and absence of disease, which allowed the detection of six malnourished children whose diagnoses as healthy are, indeed, disputable. The conclusion is that even though fuzzy sets theory might not improve prediction, it certainly does enhance clinical knowledge since it detects relationships not visible to stochastic models.


Assuntos
Humanos , Criança , Lógica Fuzzy , Pneumonia , Processos Estocásticos , Análise Discriminante , Análise Multivariada , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
11.
Braz J Med Biol Res ; 37(5): 701-9, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15107933

RESUMO

The present study compares the performance of stochastic and fuzzy models for the analysis of the relationship between clinical signs and diagnosis. Data obtained for 153 children concerning diagnosis (pneumonia, other non-pneumonia diseases, absence of disease) and seven clinical signs were divided into two samples, one for analysis and other for validation. The former was used to derive relations by multi-discriminant analysis (MDA) and by fuzzy max-min compositions (fuzzy), and the latter was used to assess the predictions drawn from each type of relation. MDA and fuzzy were closely similar in terms of prediction, with correct allocation of 75.7 to 78.3% of patients in the validation sample, and displaying only a single instance of disagreement: a patient with low level of toxemia was mistaken as not diseased by MDA and correctly taken as somehow ill by fuzzy. Concerning relations, each method provided different information, each revealing different aspects of the relations between clinical signs and diagnoses. Both methods agreed on pointing X-ray, dyspnea, and auscultation as better related with pneumonia, but only fuzzy was able to detect relations of heart rate, body temperature, toxemia and respiratory rate with pneumonia. Moreover, only fuzzy was able to detect a relationship between heart rate and absence of disease, which allowed the detection of six malnourished children whose diagnoses as healthy are, indeed, disputable. The conclusion is that even though fuzzy sets theory might not improve prediction, it certainly does enhance clinical knowledge since it detects relationships not visible to stochastic models.


Assuntos
Lógica Fuzzy , Pneumonia/diagnóstico , Criança , Humanos , Processos Estocásticos
12.
Braz J Med Biol Res ; 37(5): 755-64, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15107939

RESUMO

In view of the importance of anticipating the occurrence of critical situations in medicine, we propose the use of a fuzzy expert system to predict the need for advanced neonatal resuscitation efforts in the delivery room. This system relates the maternal medical, obstetric and neonatal characteristics to the clinical conditions of the newborn, providing a risk measurement of need of advanced neonatal resuscitation measures. It is structured as a fuzzy composition developed on the basis of the subjective perception of danger of nine neonatologists facing 61 antenatal and intrapartum clinical situations which provide a degree of association with the risk of occurrence of perinatal asphyxia. The resulting relational matrix describes the association between clinical factors and risk of perinatal asphyxia. Analyzing the inputs of the presence or absence of all 61 clinical factors, the system returns the rate of risk of perinatal asphyxia as output. A prospectively collected series of 304 cases of perinatal care was analyzed to ascertain system performance. The fuzzy expert system presented a sensitivity of 76.5% and specificity of 94.8% in the identification of the need for advanced neonatal resuscitation measures, considering a cut-off value of 5 on a scale ranging from 0 to 10. The area under the receiver operating characteristic curve was 0.93. The identification of risk situations plays an important role in the planning of health care. These preliminary results encourage us to develop further studies and to refine this model, which is intended to implement an auxiliary system able to help health care staff to make decisions in perinatal care.


Assuntos
Asfixia Neonatal/diagnóstico , Sistemas Inteligentes , Lógica Fuzzy , Ressuscitação , Adolescente , Adulto , Asfixia Neonatal/terapia , Métodos Epidemiológicos , Feminino , Humanos , Recém-Nascido
13.
Mem Inst Oswaldo Cruz ; 96(2): 141-4, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11285487

RESUMO

From August 1997 to August 1998, 334 specimens of Triatoma longipennis and 62 of T. picturata were collected in four groups of localities placed in the zone from Guadalajara, Jalisco to Tepic, Nayarit, in the West Coast of Mexico. Most T. longipennis were collected outdoors (69.2%) while most T. picturata (58.1%) were collected indoors. All collected specimens were examined for Trypanosoma cruzi infection, which was detected on 98 (29.3%) T. longipennis and 17 (27.4%) T. picturata. This study confirms the role of T. longipennis and T. picturata as some of the main T. cruzi vectors to humans in Mexico. Habitation Infestation Rate with T. longipennis was of 0.09 and with T. picturata was of 0.03 and the predominating ecotopes were pile of blocks, chicken coops, pigsties, wall crawls and beds.


Assuntos
Doença de Chagas/transmissão , Insetos Vetores/fisiologia , Triatoma/fisiologia , Trypanosoma cruzi/isolamento & purificação , Animais , Humanos , Insetos Vetores/parasitologia , México , Triatoma/parasitologia
14.
Int J Epidemiol ; 28(3): 550-7, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10405863

RESUMO

BACKGROUND: The State of São Paulo, the most populous in Brazil, was virtually free of measles from 1987 until the end of 1996 when the number of cases started to rise. It reached alarming numbers in the middle of 1997 and local health authorities decided to implement a mass vaccination campaign. METHODS: Fuzzy Decision Making techniques are applied to the design of the vaccination campaign. RESULTS: The mass vaccination strategy chosen changed the natural course of the epidemic. It had a significant impact on the epidemic in the metropolitan area of São Paulo city, but a second epidemic in the State's interior forced the public health authorities to implement a second mass vaccination campaign 2 months after the first. CONCLUSIONS: Fuzzy Logic techniques are a powerful tool for the design of control strategies against epidemics of infectious diseases.


Assuntos
Surtos de Doenças/prevenção & controle , Lógica Fuzzy , Programas de Imunização/organização & administração , Sarampo/prevenção & controle , Vacinação , Brasil/epidemiologia , Técnicas de Apoio para a Decisão , Humanos , Incidência , Sarampo/epidemiologia , Desenvolvimento de Programas
15.
Salud Publica Mex ; 31(5): 610-24, 1989.
Artigo em Espanhol | MEDLINE | ID: mdl-2609223

RESUMO

The evolution of the epidemiology of mortality in developing countries requires the use of indicators additional to cause specific mortality rates. This paper presents the leading causes of potential years of life lost in Mexico in 1983, by sex. Methodologic discussion focused on age limits and relative numbers. The indicator proved useful to assess the impact of infectious diseases, accidents and homicides as causes of premature death. It was also useful to identify years of potential life lost attributable to specific age and sex groups. The use of years of potential life lost provides valuable information to epidemiologic mortality analysis.


Assuntos
Causas de Morte , Expectativa de Vida , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , México , Pessoa de Meia-Idade , Fatores Sexuais
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