Desenvolvimento tecnológico e inovação no Brasil: desafios na área de biotecnologia

Em processament

La función masticatoria en el anciano

La función oral está intrínsecamente relacionada con actividades dia­rias esenciales como la alimentación y la comunicación. Además tiene un papel fundamental en las relaciones del individuo con otras personas y en la conser­vación del autoestima. Con el envejecimiento se producen cambios en las estructuras bucodentales que, junto a la variación del estado de salud oral y general, determinan el deterioro habitual de la función oral. No obstante, las personas mayores suelen adaptarse a muchos de los cambios del sistema esto­matognático, conducentes muchas veces a limitaciones en la función oral. En este artículo se hace una breve revisión de los cambios de la función oral en el anciano centrada en la masticación

Burning mouth and saliva

La sensación de ardor, escozor o picor generalizados en la cavidad bucal se denomina estomatodinia. Es un síntoma que puede guardar relación con otros síntomas o signos orales y no orales. Sin embargo, es frecuente que la mucosa bucal esté normal, no observándose una causa orgánica que justifique la sintomatología. Su etiología es desconocida, a pesar de que hay indicios de la participación de numerosos factores locales, sistémicos y psicológicos. Entre los factores locales, la saliva puede desempeñar un importante papel en la sintomatología del ardor bucal. Debido a sus características químicas, físicas y biológicas, la saliva presenta propiedades reológicas(físico-químicas) específicas, que determinan sus funciones indispensables para el equilibrio en la cavidad oral. En los pacientes con boca ardiente hay evidencias de cambios en la composición y tasa de flujo salivales, así como, probablemente, una alteración en la percepción de la mucosa bucal, relacionada en particular con la sensación de boca seca y alteraciones del gusto. Otro punto a considerar estriba en que las alteraciones en la composición de la saliva parecen repercutir en su viscosidad y en la sintomatología del ardor bucal. La saliva es un campo abierto a muchas investigaciones relacionadas con el ardor bucal y el conocimiento de sus propiedades, como la viscosidad, merece una atención especial, ante su aparente relación con esta sintomatología. En este artículo, los autores exponen su experiencia clínica con la boca ardiente, discutiendo asimismo algunos aspectos que parecen orientar hacia las alteraciones salivales, como uno de los factores más importantes en la etiología de la estomatodinia

Efeito inibidor da deferoxamina sobre a sobrevivência do Paracoccidioides brasiliensis em monócitos humanos: reversão por holotransferrina e não por apotransferrina

The mechanisms used by Paracoccidioides brasiliensis to survive into phagocytic cells are not clear. Cellular iron metabolism is of critical importance to the growth of several intracellular pathogens whose capacity to multiply in mononuclear phagocytes is dependent on the availability of intracellular iron. Thus, the objective of this paper was to investigate the role of intracellular iron in regulating the capacity of P. brasiliensis yeast cells to survive within human monocytes. Treatment of monocytes with deferoxamine, an iron chelator, suppressed the survival of yeasts in a concentration-dependent manner. The effect of deferoxamine was reversed by iron-saturated transferrin (holotransferrin) but not by nonsaturated transferrin (apotransferrin). These results strongly suggest that P. brasiliensis survival in human monocytes is iron dependent.Os mecanismos utilizados pelo Paracoccidioides brasiliensis para sobreviver em células fagocitárias ainda não estão elucidados. O metabolismo celular férrico é muito importante para o crescimento de inúmeros patógenos intracelulares cuja capacidade de se multiplicarem em fagócitos mononucleares é dependente da disponibilidade intracelular do íon ferro. Assim, o objetivo deste trabalho foi investigar o papel do ferro intracelular sobre a capacidade do P. brasiliensis sobreviver em monócitos humanos. O tratamento de monócitos com deferoxamina, uma droga quelante, diminuiu a sobrevivência de leveduras do fungo de forma dose-dependente. O efeito inibidor da deferoxamina sobre a sobrevivência do P. brasiliensis foi revertido por transferrina saturada com ferro (holotransferrina) mas não por transferrina insaturada (apotransferrina). Estes resultados sugerem que a sobrevivência do P. brasiliensis em monócitos humanos é dependente do íon ferro

Osteonecrosis de los maxilares asociada a bifosfonatos: revisión sistemática

En los últimos años se ha descrito una nueva complicación en la terapia con bifosfonatos: la osteonecrosis de los maxilares. Esta complicación no había sido detectada en los ensayos clínicos previos. En esta revisión sistemática de 340 casos, los pacientes afectados presentan como diagnóstico primario principalmente: mieloma múltiple (51,2%), cáncer de mama (31,4%), cáncer de próstata (7,1%) y osteoporosis (4,1%). La mandíbula resulta más afectada que el maxilar, con el 59,1%. La relación entre género femenino y masculino es de 2:2,6. El pamidronato es el bifosfonato más asociado a los casos de osteonecrosis (35,3%). Los factores de riesgos desencadenantes incluyen: exposición a bifosfonatos, infecciones orales, traumas, procedimientos quirúrgicos orales previos y terapias contra el cáncer (quimioterapia, corticoides y otros agentes citostáticos). La alteración en el equilibrio óseo, factores antiangiogénicos, inhibición en el ciclo celular de los queratinocitos y mecanismos osteolíticos generados en la infección podrían explicar la etiopatogenia en el desarrollo de esta complicación

Paracoccidioides species complex : ecology, phylogeny, sexual reproduction, and virulence

Paracoccidioidomycosis (PCM) is a deep systemic mycosis caused by human fungal pathogens of the Paracoccidioides genus. The disease is geographically restricted to subtropical areas of Latin America (from south of Mexico to north of Argentina) with a high prevalence in Brazil, Colombia, Venezuela, and Argentina [1]. The annual incidence rate in Brazil is 10–30 infections per million inhabitants, and the mean mortality rate is 1.4 per million inhabitants per year, making this disease the highest cause of mortality among systemic mycoses [2]. PCM is endemic in rural populations and mainly affects individuals engaged in agricultural activities, who inhale aerosols containing fungal material during manipulation of the soil. Molecular evolutionary studies place the genus Paracoccidioides in the thermodimorphic fungal pathogen clade related to the family Ajellomycetaceae (Ascomycetes), which includes the Blastomyces, Histoplasma, and Emmonsia genera, and with which it shares a common ancestor, Lacazia loboi. PCM can be caused by two species Paracoccidioides brasiliensis and P. lutzii [3]. P. brasiliensis has been considered a single species since its discovery, although several studies including molecular and morphological data support the split of P. brasiliensis into two species [3,4]. P. lutzii is composed of a single monophyletic and recombining population so far found in central, southwest, and north Brazil and Ecuador [3–5]. On the other hand, P. brasiliensis contains a complex of at least four different cryptic species (S1, PS2, PS3 and PS4; Figure 1A [6]). P. brasiliensis S1 represents a monophyletic and recombining population widely distributed in South America and has been associated with the majority of cases of PCM detected up until the present time. Strains belonging to P. brasiliensis S1 have previously been recovered from armadillos, soil, and penguin feces [6]. P. brasiliensis PS2 is a paraphyletic and recombining population identified so far only in Brazil and Venezuela [6]. P. brasiliensis PS3 is comprised of a monophyletic and clonal population that has been recovered in humans and armadillos in endemic regions of Colombia [6]. P. brasiliensis PS4 was recently identified and is composed of a monophyletic population of clinical isolates from Venezuela [5,7]. Besides the typical bicorn cocked hat– and barrel-shaped conidia produced by both species, P. lutzii frequently produces elongated rod-shaped conidia, a characteristic feature that may be used for species identification [3]. Because of the difficulties of conidia production in the laboratory and slight morphological differences among species, molecular identification of Paracoccidioides species has become the most common tool of choice. Several molecular markers have already been applied in population studies of the Pararacoccidioides genus, and for multilocus sequencing typing, gp43, arf, b-tub, and hsp70 loci are the best choices for species delineation [4,6]

Extracellular Paracoccidioides brasiliensis phospholipase B involvement in alveolar macrophage interaction

Background: Phospholipase B (PLB) has been reported to be one of the virulence factors for human pathogenic fungi and has also been described as necessary for the early events in infection. Based on these data, we investigated the role of PLB in virulence and modulation of the alveolar pulmonary immune response during infection using an in-vitro model of host-pathogen interaction, i.e. Paracoccidioides brasiliensis yeast cells infecting alveolar macrophage (MH-S) cells. Results: The effect of PLB was analyzed using the specific inhibitor alexidine dihydrochloride (0.25 μM), and pulmonary surfactant (100 μg mL-1), during 6 hours of co-cultivation of P. brasiliensis and MH-S cells. Alexidine dihydrochloride inhibited PLB activity by 66% and significantly decreased the adhesion and internalization of yeast cells by MH-S cells. Genes involved in phagocytosis (trl2, cd14) and the inflammatory response (nfkb, tnf-α, il-1β) were down-regulated in the presence of this PLB inhibitor. In contrast, PLB activity and internalization of yeast cells significantly increased in the presence of pulmonary surfactant; under this condition, genes such as clec2 and the pro-inflammatory inhibitor (nkrf) were up-regulated. Also, the pulmonary surfactant did not alter cytokine production, while alexidine dihydrochloride decreased the levels of interleukin-10 (IL-10) and increased the levels of IL-12 and tumor necrosis factor-α (TNF-α). In addition, gene expression analysis of plb1, sod3 and icl1 suggests that P. brasiliensis gene re-programming is effective in facilitating adaptation to this inhospitable environment, which mimics the lung-environment interaction. Conclusion: P. brasiliensis PLB activity is involved in the process of adhesion and internalization of yeast cells at the MH-S cell surface and may enhance virulence and subsequent down-regulation of macrophage activation

Evaluation of prognostic factors in stage IIA breast tumors and their correlation with mortality risk

Breast tumors exhibit extensive molecular and clinical heterogeneity. One of the most utilized breast carcinoma classifications is based on its molecular aspects and subdivides breast cancer into five major groups based on the expression of certain genes. In this study, we evaluated which factors are important in determining a prognosis after 5 years of follow-up for patients with clinical stage IIA breast tumors. We took into consideration the different phenotypes (luminal A luminal B HER-2 overexpression, basal and triple-negative), various epithelial-mesenchymal (EMT) molecular markers and adhesion molecules (E-cadherin, P-cadherin, N-cadherin, vimentin, twist snail and slug) and NOS-2, in addition to clinical and demographic data, tumor characteristics and treatment types. METHODS: The study population consisted of 82 patients with breast cancer. We analyzed eight molecular markers by immunohistochemistry on tissue microarrays containing breast tumor specimens from patients with ten years of follow-up, and we classified each tumor according to its estrogen receptor, progesterone receptor and HER-2 expression. We then placed the tumor into one of the above categories. RESULTS: The presence of several clinical and demographic factors, various histopathologies, treatment forms and several immunohistochemical markers were not associated with a worse prognosis for group IIA patients. The factors that were associated with a mortality risk were the triple-negative (odds ratio (OR) = 11.8, 95% confident interval (CI) = 2.0-70.3, P = 0.007) and basal (OR =18.4, 95% CI = 1.8-184.7, P= 0.013) phenotypic patterns. CONCLUSIONS: The EMT markers and NOS-2 were not mortality risk factors. Basal and triple-negative phenotypic patterns were related to a higher mortality risk in patients with stage IIA tumors

Esclerosis tuberosa y manifestaciones orales: caso clínico

La esclerosis tuberosa (ET) es una anomalía congénita del desarrollo embrionario que se transmite de forma autosómica dominante y tiene diferentes formas de expresión clínica. Se clasifica dentro de las denominadas facomatosis (phakos 'mancha' y oma 'tumor'), que son anomalías del desarrollo, susceptibles de originar tumores y/o hamartomas del sistema nervioso. Es importante destacar que las lesiones del sistema nervioso se acompañan, prácticamente siempre, de anomalías cutáneas. En este trabajo presentamos el caso de una paciente de 55 años de edad, diagnosticada desde hace años de esclerosis tuberosa, que cursa con lesiones intraorales compatibles clínicamente con fibromas. Estas lesiones de aspecto fibromatoso se presentan sobre todo en el labio inferior y en ambas mucosas yugales, localización poco referenciada para esta manifestación en la enfermedad de base que nos ocupa. La anatomía patológica sugiere lesiones compatibles con angiomiolipoma. También repasamos los datos referentes a la ET, se describen las implicaciones orales de la misma y en base al resultado histopatológico obtenido se revisa el significado del término angiomiolipoma.Tuberous sclerosis (TS) is a congenital anomaly in the development of the embryo which is transmitted through the autosomal dominant gene. It has various forms of clinical expression. It is classified as one of what are known as Phacomatoses (phakos stain and oma tumour), which are development anomalies that can originate tumours and/or hamartomas in the nervous system. Lesions in the nervous system are nearly always accompanied by cutaneous anomalies. In this study we introduce the case of a woman patient aged 55, diagnosed several years earlier with Tuberous Sclerosis, who attended for intraoral lesions which were clinically compatible with fibromata. These lesions of fibrous appearance occurred above all on the lower lip and in both cheeks' mucous membranes, little mentioned in the literature as a site for such a manifestation of TS. The pathological anatomy suggested lesions compatible with Angiomyolipoma. In addition, the data referring to TS are reviewed; its implications for the mouth are described; and histopathological results are used to examine the significance of the word Angiomyolipoma

Glyceraldehyde-3-phosphate dehydrogenase of Paracoccidioides brasiliensis is a cell surface protein involved in fungal adhesion to extracellular matrix proteins and interaction with cells

The pathogenic fungus Paracoccidioides brasiliensis causes paracoccidioidomycosis, a pulmonary mycosis acquired by inhalation of fungal airborne propagules, which may disseminate to several organs and tissues, leading to a severe form of the disease. Adhesion to and invasion of host cells are essential steps involved in the infection and dissemination of pathogens. Furthermore, pathogens use their surface molecules to bind to host extracellular matrix components to establish infection. Here, we report the characterization of the glyceraldehyde-3-phosphate dehydrogenase (GAPDH) of P. brasiliensis as an adhesin, which can be related to fungus adhesion and invasion. the P. brasiliensis GAPDH was overexpressed in Escherichia coli, and polyclonal antibody against this protein was obtained. By immunoelectron microscopy and Western blot analysis, GAPDH was detected in the cytoplasm and the cell wall of the yeast phase of P. brasiliensis. the recombinant GAPDH was found to bind to fibronectin, laminin, and type I collagen in ligand far-Western blot assays. of special note, the treatment of P. brasiliensis yeast cells with anti-GAPDH polyclonal antibody and the incubation of pneumocytes with the recombinant protein promoted inhibition of adherence and internalization of P. brasiliensis to those in vitro-cultured cells. These observations indicate that the cell wall-associated form of the GAPDH in P. brasiliensis could be involved in mediating binding of fungal cells to fibronectin, type I collagen, and laminin, thus contributing to the adhesion of the microorganism to host tissues and to the dissemination of infection.Univ Fed Goias, Inst Ciencias Biol, Mol Biol Lab, BR-74001970 Goiania, Go, BrazilUniv Brasilia, BR-70910900 Brasilia, DF, BrazilUniv Estadual Julio Mesquita Filho, Araraquara, SP, BrazilUniversidade Federal de São Paulo, São Paulo, BrazilUniversidade Federal de São Paulo, São Paulo, BrazilWeb of Scienc