Probiotics, prebiotics and food allergy.

Summary: Background. The prevalence of food allergy (FA) has increased, a possible consequence of intestinal dysbiosis, environmental or genetic factors. Currently, no formal indications exist for probiotic or prebiotic supplementation in FA. This review aims to analyse the role of probiotics and prebiotics in the prevention and treatment of FA. Methods. A PubMed/Medline search was carried out on articles published between 2011 and 2021 with the following query: ("Food Hypersensitivity"[Mesh]) AND (("Probiotics"[Mesh]) OR ("Prebiotics"[Mesh])). Subsequently, the titles and abstracts were analysed and selected according to established criteria. After full reading of these articles, 54 were included and a narrative review was performed. Results. The review was structured in the following sections: i) Cow's Milk Proteins Allergy (CMA), ii) Food Allergy to Peanuts and iii) Prevention of Food Allergy. In CMA, several studies have supported the benefits of extensively hydrolysed casein formula supplemented with Lactobacillus Rhamnosus GG in the earlier acquisition of tolerance to cow's milk proteins, resolution of gastrointestinal symptoms and prevention of other allergic manifestations. In peanut oral immunotherapy (OI), supplementation with Lactobacillus Rhamnosus CGMCC 1.3724 seems to have a favourable impact in inducing a sustained desensitization response. Regarding the use of probiotics in the prevention of FA, this assumption lacks robust scientific evidence in order to confirm the effectiveness. Current evidence supports the use of oligosaccharides from breast milk in the first months of life for preventing atopic dermatitis, FA and asthma. Conclusions. The potential of probiotics to be used as therapeutic adjuvants in CMA and peanut OI is promising. However, there is inconsistency regarding the type of probiotic, the dose and duration of supplementation. Further studies are needed to clarify the role of probiotics and prebiotics in FA.

Fabrication and characterization of polyimide-based 'smooth' titanium nitride microelectrode arrays for neural stimulation and recording.

OBJECTIVE: As electrodes are required to interact with sub-millimeter neural structures, innovative microfabrication processes are required to enable fabrication of microdevices involved in such stimulation and/or recording. This requires the development of highly integrated and miniaturized systems, comprising die-integration-compatible technology and flexible microelectrodes. To elicit selective stimulation and recordings of sub-neural structures, such microfabrication process flow can beneficiate from the integration of titanium nitride (TiN) microelectrodes onto a polyimide substrate. Finally, assembling onto cuffs is required, as well as electrode characterization. APPROACH: Flexible TiN microelectrode array integration and miniaturization was achieved through microfabrication technology based on microelectromechanical systems (MEMS) and complementary metal-oxide semiconductor processing techniques and materials. They are highly reproducible processes, granting extreme control over the feature size and shape, as well as enabling the integration of on-chip electronics. This design is intended to enhance the integration of future electronic modules, with high gains on device miniaturization. MAIN RESULTS: (a) Fabrication of two electrode designs, (1) 2 mm long array with 14 TiN square-shaped microelectrodes (80 × 80 µm2), and (2) an electrode array with 2 mm × 80 µm contacts. The average impedances at 1 kHz were 59 and 5.5 kΩ, respectively, for the smaller and larger contacts. Both designs were patterned on a flexible substrate and directly interconnected with a silicon chip. (b) Integration of flexible microelectrode array onto a cuff electrode designed for acute stimulation of the sub-millimeter nerves. (c) The TiN electrodes exhibited capacitive charge transfer, a water window of -0.6 V to 0.8 V, and a maximum charge injection capacity of 154 ± 16 µC cm-2. SIGNIFICANCE: We present the concept, fabrication and characterization of composite and flexible cuff electrodes, compatible with post-processing and MEMS packaging technologies, which allow for compact integration with control, readout and RF electronics. The fabricated TiN microelectrodes were electrochemically characterized and exhibited a comparable performance to other state-of-the-art electrodes for neural stimulation and recording. Therefore, the presented TiN-on-polyimide microelectrodes, released from silicon wafers, are a promising solution for neural interfaces targeted at sub-millimeter nerves, which may benefit from future upgrades with die-electronic modules.

Design and manufacturing challenges of optogenetic neural interfaces: a review.

Optogenetics is a relatively new technology to achieve cell-type specific neuromodulation with millisecond-scale temporal precision. Optogenetic tools are being developed to address neuroscience challenges, and to improve the knowledge about brain networks, with the ultimate aim of catalyzing new treatments for brain disorders and diseases. To reach this ambitious goal the implementation of mature and reliable engineered tools is required. The success of optogenetics relies on optical tools that can deliver light into the neural tissue. Objective/Approach: Here, the design and manufacturing approaches available to the scientific community are reviewed, and current challenges to accomplish appropriate scalable, multimodal and wireless optical devices are discussed. SIGNIFICANCE: Overall, this review aims at presenting a helpful guidance to the engineering and design of optical microsystems for optogenetic applications.

Azole-resistant Candida albicans from a wild Brazilian porcupine (Coendou prehensilis): a sign of an environmental imbalance?

This study aimed at evaluating the in vitro antifungal susceptibility of Candida albicans isolates obtained during necropsy of a wild Brazilian porcupine and the mechanism of azole resistance. Initially, we investigated the in vitro susceptibility of the three isolates to amphotericin B, caspofungin, fluconazole, itraconazole, ketoconazole and voriconazole. Afterwards, three sub-inhibitory concentrations (47, 21 and 12 mg/l) of promethazine, an efflux pump inhibitor, were tested in combination with the antifungal drugs in order to evaluate the role of these pumps in the development of antifungal resistance. In addition, the three isolates were submitted to RAPD-PCR and M13-fingerprinting analyses. The minimum inhibitory concentrations (MICs) obtained with the isolates were 1, 0.03125, 250, 125, 8 and 250 mg/l for amphotericin B, caspofungin, fluconazole, itraconazole, ketoconazole and voriconazole, respectively, and the isolates were found to be resistant to all tested azoles. The addition of the three subinhibitory concentrations of promethazine resulted in statistically significant (P < 0.05) reductions in the MICs for all tested drugs, with decreases to azoles being statistically greater than those for amphotericin B and caspofungin (P < 0.05). The molecular analyses showed a genetic similarity among the three tested isolates, suggesting the occurrence of candidemia in the studied animal. These findings highlight the importance of monitoring antifungal susceptibility of Candida spp. from veterinary sources, especially as they may indicate the occurrence of primary azole resistance even in wild animals.

Caracterização físico-química e análises por espectrofotometria e cromatografia de Peperomia pellucida L. (H. B. K. ) / Physical chemical characterization and spectrophotometric analysis and chromatography (TLC) of the Peperomia pellucida L. (H. B. K. )

O objetivo deste trabalho foi realizar a caracterização físico-química do pó e da tintura, e análise por espectrofotometria e cromatografia do extrato seco de Peperomia pellucida L. (H. B. K.). As metodologias seguiram a Farmacopéia Brasileira IV ed., com exceção da prospecção química, da espectrofotometria, da obtenção do perfil cromatográfico do extrato seco, e determinação do resíduo seco. A prospecção química revelou a presença de saponinas espumídicas; açúcares redutores; proteínas e aminoácidos; fenóis; taninos; flavonóides; esteróides e triterpenóides. Na análise por CCD, o melhor perfil da fração flavonoídica foi obtido com MeOH/CHOOH (90:10). Foi confirmada, através de CLAE, a presença de 3',4',7-tri-O-metoxiflavona no extrato seco deste material vegetal. Os resultados obtidos contribuem para a determinação de especificações de uma futura monografia em Farmacopéias da Peperomia pellucida L. (H.B.K.).

The aim of this study was the physical chemical characterization of the powder and the tincture, and the chromatographic and spectrophotometric analysis of the Peperomiapellucida L. (H. B. K.) dry extract. The methodology followed the Farmacopeia Brasileira IV ed., except for the chemical prospection, the chromatographic profile obtained and the spectrophotometry of the dry extract, and determination of dried residues. The chemical prospection revealed the presence of foaming saponins; reducing sugars; proteins and amino acids; phenols; tannins; flavonoids; steroids and triterpenoids; depsideos and depsidones. The best profile from TLC for flavonoidic fraction was obtained with methanol/formic acid (90:10 v/v). HPLC confirmed the presence of 3 ',4',7-tri-methoxyflavone in the dry extract of the plant material. The results obtained in this work should contribute for the determination of specifications for a future monograph on Peperomia pellucida L. (H.B.K.).

Viral protease inhibitors affect the production of virulence factors in Cryptococcus neoformans.

The effects of the protease inhibitors saquinavir, darunavir, ritonavir, and indinavir on growth inhibition, protease and phospholipase activities, as well as capsule thickness of Cryptococcus neoformans were investigated. Viral protease inhibitors did not reduce fungal growth when tested in concentrations ranging from 0.001 to 1.000 mg/L. A tendency toward increasing phospholipase activity was observed with the highest tested drug concentration in a strain-specific pattern. However, these drugs reduced protease activity as well as capsule production. Our results confirm a previous finding that antiretroviral drugs affect the production of important virulence factors of C. neoformans.

Sesquiterpene farnesol contributes to increased susceptibility to ß-lactams in strains of Burkholderia pseudomallei.

This study aimed to evaluate the in vitro combination of farnesol and ß-lactams against Burkholderia pseudomallei. A total of 12 ß-lactamase-positive strains were tested according to CLSI standards. All strains were inhibited by farnesol, with MICs ranging from 75 to 150 µM. The combination of this compound with ß-lactams resulted in statistically significant ß-lactam MIC reduction (P ≤ 0.05). This study provides new perspectives for the use of farnesol combined with ß-lactam antibiotics against strains of B. pseudomallei.

Doenca de Corino de Andrade. A proposito de um caso. / Corino de Andrade's disease. Apropos of a case

Os autores relatam um caso de sindrome de ma-absorcao intestinal por amiloidose familiar do tipo portugues. A proposito, fazem uma revisao dessa doenca com especial atencao ao acometimento digestivo, discutindo os possiveis mecanismos fisiopatologicos da ma-absorcao nesse caso