Novel strategies for preventing dysbiosis in the oral cavity

Oral diseases affect over three billion people worldwide, making it one of the most common infections. Recent studies show that one approach to reducing the risk of chronic infections, such as caries, gingivitis, periodontitis, and halitosis, is to control the ecology of the oral microbiome instead of completely removing both the harmful and beneficial microorganisms. This is based on the knowledge that oral diseases are not caused by a single pathogen but rather by a shift in the homeostasis of the entire microbiota, a process known as dysbiosis. Consequently, it is of the utmost importance to implement strategies that are able to prevent and control oral dysbiosis to avoid serious complications, including heart, lung, and other systemic diseases. Conventional treatments include the use of antibiotics, which further disrupt the equilibrium in the oral microbiota, together with the mechanical removal of the decayed cavity area following its formation. Therefore, it is imperative to implement alternative strategies with the potential to overcome the disadvantages of the current therapy, namely, the use of broad-spectrum antibiotics. In this sense, probiotics and postbiotics have received particular attention since they can modulate the oral microbiota and decrease the dysbiosis rate in the oral cavity. However, their mechanisms of action need to be addressed to clarify and drive their possible applications as preventive strategies. In this sense, this review provides an overview of the potential of probiotics and postbiotics, focusing on their antimicrobial and antibiofilm activities as well as their ability to modulate the inflammatory response. Finally, it also showcases the main advantages and disadvantages of orodispersible films—a promising delivery mechanism for both probiotics and postbiotics to target oral dysbiosis.info:eu-repo/semantics/publishedVersio

Design of protein-based liquefied cell-laden capsules with bioinspired adhesion for tissue engineering

Platforms with liquid cores are extensively explored as cell delivery vehicles for cell-based therapies and tissue engineering. However, the recurrence of synthetic materials can impair its translation into the clinic. Inspired by the adhesive proteins secreted by mussels, liquefied capsule is developed using gelatin modified with hydroxypyridinones (Gel-HOPO), a catechol analogue with oxidant-resistant properties. The protein-based liquefied macrocapsule permitted the compartmentalization of living cells by an approachable and non-time-consuming methodology resorting to i) superhydrophobic surfaces as a processing platform of hydrogel beads, ii) gelation of gelatin at temperatures < 25 °C, iii) iron coordination of the hydroxypyridinone (HOPO) moieties at physiological pH, and iv) core liquefaction at 37 °C. With the design of a proteolytically degradable shell, the possibility of encapsulating human adipose-derived mesenchymal stem cells (hASC) with and without the presence of polycaprolactone microparticles (μPCL) is evaluated. Showing prevalence toward adhesion to the inner shell wall, hASC formed a monolayer evidencing the biocompatibility and adequate mechanical properties of these platforms for proliferation, diminishing the need for μPCL as a supporting substrate. This new protein-based liquefied platform can provide biofactories devices of both fundamental and practical importance for tissue engineering and regenerative medicine or in other biotechnology fields.publishe

Immune response: the Achilles’ heel of the stem cell-based regenerative therapies

Besides trauma, several pathological conditions which directly affect the normal functioning of organs, require new therapeutic strategies to repair damaged or diseased tissues. Tissue regeneration is a complex and spatiotemporal process involving a plethora of cell types, including various immune cells and stem cells in a synchronized relationship. However, individual parameters, namely ageing, obesity, diabetes, and chronic conditions, have been intrinsically correlated with poor regenerative properties of adult tissues. While vast progress has been made regarding stem cell-based therapy to direct self-healing, the immune response is still the Achilles’ heel of such strategies. Whereas the role of effector immune cells has been well defined along the regenerative process, an understanding of the behavior of the main adult stem cells, namely mesenchymal stem cells (MSCs) and hematopoietic stem and progenitor cells (HSPCs), along the different phases of the regenerative process could clarify how these stem cells can be used to positively influence the immune response. In this scope, this review highlights the main interactions between these stem cells and immune cells during tissue repair, exploring the most important regenerative properties of stem cells and correlating them with the modulation of the immune response during tissue regeneration. Furthermore, the utmost strategies used to explore how the behavior and stem cell fate are affected by specific microenvironments and/or stimuli usually found during a regenerative process, are emphasized. This clarification may provide critical insight into the molecular mechanisms by which stem cells modulate the immune response in a positive feedback loop toward tissue repair

The development of the self and the process of hiper-individualization: inquiries to the Dialogical Psychology

En psychologie, la perspective dialogique est associée à la théorie du soi (self) qui a été développée, en particulier, à travers les théories du soi dialogique (dialogic self theory; DST). Bien que des avancées théoriques et méthodologiques importantes aient été réalisées par les DST concernant notre compréhension de l'organisation dynamique des structures du soi chez les processus microgénétiques (temporels), ces théories requièrent des recherches qui explorent en profondeur le développement du soi, lesquels doivent porter sur les multiples niveaux temporels et leur rapport mutuel. Cet article propose d'explorer cette lacune à partir des approches dialogiques psychologiques, soit leurs bases sémiotique-culturelles, phénoménologiques et constructionnistes. Enfin, on analyse les complexes sémiotiques de genre, de race et de religion, ainsi que leur rôle sur le plan des changements de l'organisation temporelle du soi d'un adolescent.En psicología, a la mirada dialógica se la relacionan teorías del self, especialmente, la Teoría del Self Dialógico (TSD). Aunque haya avanzado significativamente en lo que atañe a la comprensión de la organización dinámica de la estructura del self en el tiempo microgenético, la perspectiva carece de estudios que profundicen la comprensión del desarrollo del self, tomando como base los distintos niveles temporales y sus relaciones. Este estudio se propone a explotar esta laguna a partir de la tríada epistemológica del abordaje dialógico, es decir, sus bases semiótico-culturales, fenomenológicas y construccionistas. Enseguida, presenta un estudio de caso en el que se analizarán transiciones de desarrollo de un adolescente, considerándose los complejos semióticos de género, raza y religión, y su papel en las transformaciones vividas en términos de organización temporal del self.Em psicologia, à perspectiva dialógica estão associadas teorias do self, em especial a Teoria do Self Dialógico (TSD). Embora avanços consistentes venham sendo alcançados no que se refere à compreensão da organização dinâmica da estrutura do self no tempo microgenético, a teoria carece de estudos que se aprofundem na compreensão do desenvolvimento do self, tomando-se por base os distintos níveis temporais e suas relações. Este estudo propõe explorar essa lacuna, tomando por ponto de partida a tríade epistemológica da abordagem dialógica, a saber, suas bases semiótico-culturais, fenomenológicas e construcionistas. Em seguida, apresentará um estudo de caso em que serão analisadas as transições de desenvolvimento de um adolescente, considerando-se os complexos semióticos de gênero, raça e religião e seu papel nas transformações vividas em termos da organização temporal do self.In Psychology the dialogical perspective is associated with various theories of self, in special, the Dialogical Self Theory (DST). Although important theoretical and methodological advances have been achieved by DST concerning our comprehension of the dynamic organization of the structure of the self in micro-genetic (temporal) processes, this perspective is in need of theories that explore in depth the development of the self including multiple temporal levels of organization and their mutual relationships. This paper aims to explore the triadic epistemological basis of the dialogical perspective in psychology, i.e., the cultural-semiotic basis, the phenomenology, and constructionism. Then, a case study concerning developmental transitions of an adolescent will be presented. We will analyze the semiotic complexes of gender, race and religion, as well as their role in the personal changes lived by him, in terms of the temporal organization of the self

Merging zones approach in a flow-based platform for the determination of the total protein content in microbiological samples

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Synergistic activity of cold pressed seed oils from Indian neem (Azadirachta indica), karanja (Pongamia glabra) and aloe vera gel (Aloe barbadensis) in a cosmeceutical moisturizer

The increased interest and knowledge on the beneficial activity of plants and their compounds in human health have contributed to the development of several drugs, widely used in clinical practice worldwideinfo:eu-repo/semantics/publishedVersio

The Dwarf Galaxy Population of the Dorado group down to Mv=-11

We present V and I CCD photometry of suspected low-surface brightness dwarf galaxies detected in a survey covering ~2.4 deg^2 around the central region of the Dorado group of galaxies. The low-surface brightness galaxies were chosen based on their sizes and magnitudes at the limiting isophote of 26.0V\mu. The selected galaxies have magnitudes brighter than V=20 (Mv=-11 for an assumed distance to the group of 17.2 Mpc), with central surface brightnesses \mu0>22.5 V mag/arcsec^2, scale lengths h>2'', and diameters > 14'' at the limiting isophote. Using these criteria, we identified 69 dwarf galaxy candidates. Four of them are large very low-surface brightness galaxies that were detected on a smoothed image, after masking high surface brightness objects. Monte Carlo simulations performed to estimate completeness, photometric uncertainties and to evaluate our ability to detect extended low-surface brightness galaxies show that the completeness fraction is, on average, > 80% for dwarf galaxies with $-17<M_{V}<-10.5$ and 22.5<\mu0<25.5 V mag/arcsec^2, for the range of sizes considered by us (D>14''). The V-I colors of the dwarf candidates vary from -0.3 to 2.3 with a peak on V-I=0.98, suggesting a range of different stellar populations in these galaxies. The projected surface density of the dwarf galaxies shows a concentration towards the group center similar in extent to that found around five X-ray groups and the elliptical galaxy NGC1132 studied by Mulchaey and Zabludoff (1999), suggesting that the dwarf galaxies in Dorado are probably physically associated with the overall potential well of the group.Comment: 32 pages, 16 postscript figures and 3 figures in GIF format, aastex v5.0. To appear in The Astronomical Journal, January 200

Características geoambientais do planalto sedimentar da ibiapaba - uma ilha de refúgio

Características geoambientais do planaltosedimentar da ibiapaba - uma ilha de refúgio      

Integrating Diphenyl Diselenide and Its MeHg+ Detoxificant Mechanism on a Conceptual DFT Framework

Methylmercury is an important environmental contaminant and its toxicity in vertebrates is associated with its interaction with selenium (e.g., selenol groups of selenoproteins or HSe- the pivotal metabolite for selenium incorporation into selenoproteins). In a previous study, we demonstrated that diphenyl diselenide (PhSe)2 decreased the deposition of Hg in mice treated with MeHg+. We hypothesized that (PhSe)2 could be reduced metabolically to its selenol intermediate phenylselenol (PhSeH), which reacted with MeHg+ to form PhSeHgMe. To further support our hypothesis, in this work, we investigate the electronic chemical reactivity descriptors at ZORA-OPBE-D3(BJ)/ level of theory using the Fukui functions and the Dual descriptors. The results indicate that (PhSe)2 and diphenyl disulfide (PhS)2 (f+ > f- ) act as poor nucleophiles towards MeHg+ and thus cannot be the detoxificant agent. As further proof, the reaction between diphenyl diselenide and MeHgCl was followed via UV-vis spectrophotometry and the spectra of the relevant species were computed using time-dependent density functional theory (TD-DFT) (CPCM-ZORA-CAM-B3LYP/ZORA-def2-TZVP). The large aromatic system in (PhSe)2 ensures the delocalization of electrons and directly influences the HOMO-LUMO gap (HLG) (3.34 eV) < HLG of PhSeH (3.99 eV). A similar trend was observed with HLG (2.65 eV) for (PhS)2 and 4.13 eV for PhSH. This selenol intermediate is the active reactant, experimentally generated from the reduction of (PhSe)2 by NaBH4, which in presence of MeHgCl forms methylmercury phenylselenide complex (PhSeHgMe), i.e. a non-toxic metabolite of methylmercury formed after administration of (PhSe)2 to mice

Impact of a novel sugarcane straw extract-based ingredient on skin microbiota via a new preclinical in vitro model

During cosmetic product development, the impact on the skin microbiota needs to be evaluated, as it plays an important role in skin health. Clinical studies are frequently used to assess cosmetic effects, but are expensive, time-consuming and require finished ingredients, which may be a limiting factor. Thus, this study had two main objectives, the development of a preclinical in vitro model for the evaluation of the effect of cosmetic ingredients on the skin microbiota, and its use to evaluate a novel sugarcane straw extract-based ingredient. In the development of the preclinical in vitro model, the microbiota incubation time and atmospheric conditions were optimized. The model was validated using a benchmark ingredient with reported in vivo effects on skin microbiota. Then, the new sugarcane straw extract-based ingredient was tested in the model, using skin microbiota samples from 12 healthy female volunteers. The impact on microbial groups was analyzed using qPCR and next-generation sequencing. The best conditions for the in vitro model were 24 h incubation under aerobic conditions. Furthermore, the results obtained with the benchmark ingredient agreed with those obtained in vivo, thus validating our model. Sugarcane straw extract-based ingredient was found to have no effect on community α-diversity, however it appears to affect S. epidermidis. In conclusion, the developed model can be used as a tool to assess the impact of novel cosmetic ingredients on skin microbiota. Also, the novel ingredient seems to have an impact on commensal S. epidermidis.info:eu-repo/semantics/publishedVersio