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Redoxome is the network of redox reactions and redox active species (ReAS) that affect the homeostasis of cells and tissues. Due to the intense and constant interaction with external agents, the human skin has a robust redox signalling framework with specific pathways and magnitudes. The establishment of the skin redoxome concept is key to expanding knowledge of skin disorders and establishing better strategies for their prevention and treatment. This review starts with its definition and progress to propose how the master redox regulators are maintained and activated in the different conditions experienced by the skin and how the lack of redox regulation is involved in the accumulation of several oxidation end products that are correlated with various skin disorders.

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Leishmaniasis is a serious and endemic infectious disease that has been reported in more than 90 countries and territories. The classical treatment presents a series of problems ranging from difficulty in administration, development of resistance, and a series of side effects. Photodynamic therapy (PDT) has already shown great potential for use as a treatment for leishmaniasis that is effective and non-invasive, with very minor side effects. PDT can also be inexpensive and easy to administer. In this review, we will report the most recent developments in the field, starting with the chemical diversity of photosensitizers, highlighting important mechanistic aspects, and noting information that may assist in designing and developing new and promising photosensitizer molecules.

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Leishmaniasis is a serious and endemic infectious disease that has been reported in more than 90 countries and territories. The classical treatment presents a series of problems ranging from difficulty in administration, development of resistance, and a series of side effects. Photodynamic therapy (PDT) has already shown great potential for use as a treatment for leishmaniasis that is effective and non-invasive, with very minor side effects. PDT can also be inexpensive and easy to administer. In this review, we will report the most recent developments in the field, starting with the chemical diversity of photosensitizers, highlighting important mechanistic aspects, and noting information that may assist in designing and developing new and promising photosensitizer molecules.

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The scientific publication landscape is changing quickly, with an enormous increase in options and models. Articles can be published in a complex variety of journals that differ in their presentation format (online-only or in-print), editorial organizations that maintain them (commercial and/or society-based), editorial handling (academic or professional editors), editorial board composition (academic or professional), payment options to cover editorial costs (open access or pay-to-read), indexation, visibility, branding, and other aspects. Additionally, online submissions of non-revised versions of manuscripts prior to seeking publication in a peer-reviewed journal (a practice known as pre-printing) are a growing trend in biological sciences. In this changing landscape, researchers in biochemistry and molecular biology must re-think their priorities in terms of scientific output dissemination. The evaluation processes and institutional funding for scientific publications should also be revised accordingly. This article presents the results of discussions within the Department of Biochemistry, University of São Paulo, on this subject.

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BACKGROUND: The risk factors associated with delayed graft function (DGF) and its impact in kidney transplant (KTx) outcomes remains controversial; it is possible that donor renal characteristics influence the initial graft function in KTx. OBJECTIVE: Evaluate risk factors associated with DGF and its impact in KTx outcomes. METHODS: One hundred six mate KTx mate recipients performed in a single center were grouped according to the presence or absence of DGF. RESULTS: Donors were predominantly men (58%); 70% were standard criteria type, with a mean Kidney Donor Profile Index (KDPI) of 62% ± 28%, median age of 42 ± 15 and presenting hospitalization time of 6 ± 5 days. KTx recipients presented an overall DGF rate of 82%, lasting 12 ± 7 days. Pairs presenting DGF were older than pairs without DGF (P = .008), while cold ischemia time (CIT) was significantly shorter in the group without DGF compared to those presenting DGF (P = .003). The KDPI of the KTx pairs was significantly higher in pairs with DGF versus without DGF (P = .04). No statistically significant differences in 1 year allograft and patient survival were observed. Recipient age (odds ratio = 6.3, confidence interval = 1.5-25.8; P = .009) and CIT (odds ratio = 4.6, confidence interval = 1.2-17.7; P = .002) were significantly associated with DGF. CONCLUSION: This study suggests that recipient age, cold ischemic time, and KDPI are factors associated with DGF. In addition, DGF had no impact on 1-year renal function, allograft, and patient survival. In the transplant conditions of our country, Brazil, CIT seems to represent an important variable to be managed, and the aim should be to reduce this factor as much as possible.

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The rupture of the Fundão mine dam in Mariana municipality, Minas Gerais State, Brazil, spilled the tailings across the Doce River basin. These tailings, composed of residues discarded from the beneficiation of iron ore, are rich in SiO and AlO, as well as some ether amine compounds and NaOH. The aim of this study was to assess the distribution of these sediments, as well as their effect on the riparian zones reached, as compared with preserved sites. Sediment deposition in the river resulted in a morphological change from a meandering profile to a braided aspect. The nutrient and mineral content (P, K, Ca, Mg, Cu, Fe, Mn, Zn, and NO) and soil organic matter of the sediments were depleted, whereas NH, Na, and pH increased. A random presence of ether amines in the sediments was confirmed by quantitative and chromatographic analyses, with concentrations ranging from 0 to 57.8 mg kg; Na reached values as high as 150 mg kg. The impact of the dam tailings on biota was assessed by estimating total microbial biomass (phospholipid fatty acids), which were depleted in sediments relative to soils from preserved sites. Overall plant mortality, as well as a low resilience capacity, were also observed. Ether amines and Na present in the sediments had a strong toxic effect in the environment. Identification of these substances as the main impact factors will help guide future remediation efforts.

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The scientific publication landscape is changing quickly, with an enormous increase in options and models. Articles can be published in a complex variety of journals that differ in their presentation format (online-only or in-print), editorial organizations that maintain them (commercial and/or society-based), editorial handling (academic or professional editors), editorial board composition (academic or professional), payment options to cover editorial costs (open access or pay-to-read), indexation, visibility, branding, and other aspects. Additionally, online submissions of non-revised versions of manuscripts prior to seeking publication in a peer-reviewed journal (a practice known as pre-printing) are a growing trend in biological sciences. In this changing landscape, researchers in biochemistry and molecular biology must re-think their priorities in terms of scientific output dissemination. The evaluation processes and institutional funding for scientific publications should also be revised accordingly. This article presents the results of discussions within the Department of Biochemistry, University of São Paulo, on this subject.

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OBJECTIVE: Methods that can be used to analyse hair damage and to support a claim of hair protection are important for the cosmetic industry. There are many approaches available, but they are usually laborious and expensive. The researchers propose a simple fluorescence method that is based upon the emissive properties of damaged hair. METHODS: Hair fluorescence was observed when using both fluorimetry and microscopic procedures. The method was developed by comparing native hair with hair that was damaged by UVA and visible light. RESULTS: Spectroscopic properties (absorption and emission) of hair in the visible range are presented. The changes in the emissive properties of hair during irradiation were characterized and they were correlated with photobleaching, which is due to the generation of singlet oxygen. Emissions were also obtained in the hair shafts that had been previously treated with chamomile extract and this treatment was able to avoid hair bleaching. CONCLUSION: The emissive properties of hair in the visible range can be used as a tool for the evaluation of hair damage and protection. This method can be useful as a tool in order to claim substantiation.

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We investigate the basin of attraction properties and its boundaries for chimera states in a circulant network of Hénon maps. It is known that coexisting basins of attraction lead to a hysteretic behaviour in the diagrams of the density of states as a function of a varying parameter. Chimera states, for which coherent and incoherent domains occur simultaneously, emerge as a consequence of the coexistence of basin of attractions for each state. Consequently, the distribution of chimera states can remain invariant by a parameter change, and it can also suffer subtle changes when one of the basins ceases to exist. A similar phenomenon is observed when perturbations are applied in the initial conditions. By means of the uncertainty exponent, we characterise the basin boundaries between the coherent and chimera states, and between the incoherent and chimera states. This way, we show that the density of chimera states can be not only moderately sensitive but also highly sensitive to initial conditions. This chimera's dilemma is a consequence of the fractal and riddled nature of the basin boundaries.

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The characterization of neuronal connectivity is one of the most important matters in neuroscience. In this work, we show that a recently proposed informational quantity, the causal mutual information, employed with an appropriate methodology, can be used not only to correctly infer the direction of the underlying physical synapses, but also to identify their excitatory or inhibitory nature, considering easy to handle and measure bivariate time series. The success of our approach relies on a surprising property found in neuronal networks by which nonadjacent neurons do "understand" each other (positive mutual information), however, this exchange of information is not capable of causing effect (zero transfer entropy). Remarkably, inhibitory connections, responsible for enhancing synchronization, transfer more information than excitatory connections, known to enhance entropy in the network. We also demonstrate that our methodology can be used to correctly infer directionality of synapses even in the presence of dynamic and observational Gaussian noise, and is also successful in providing the effective directionality of intermodular connectivity, when only mean fields can be measured.

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OBJECTIVES: Although dementia typically occurs in older people, it can also emerge in people aged younger than 65 years in the form of young-onset dementia, the most common type of which is Alzheimer's disease (AD). However, few studies have examined the needs of persons with young-onset AD (YO-AD) and their families, and cross-cultural research on the topic is even scarcer. In response, we investigated the situations, experiences and needs for assistance of carers of persons with YO-AD in Brazil and Norway. METHODS: As part of our qualitative study, we formed a convenience sample of Brazilian (n = 9; 7 women) and Norwegian carers (n = 11; 6 women) in 2014 and 2015, respectively, and analysed data in light of a modified version of grounded theory. RESULTS: Carers' narratives from both countries revealed five common themes in terms of how YO-AD affected carers' psychological and emotional well-being, physical well-being, professional and financial well-being, social lives and need for support services. CONCLUSIONS: The infrequent differences between carers of persons with YO-AD in Brazil and Norway indicate that carers' problems are highly similar regardless of cultural differences and public services provided. Copyright © 2017 John Wiley & Sons, Ltd.

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We study the capacity of Hodgkin-Huxley neuron in a network to change temporarily or permanently their connections and behavior, the so called spike timing-dependent plasticity (STDP), as a function of their synchronous behavior. We consider STDP of excitatory and inhibitory synapses driven by Hebbian rules. We show that the final state of networks evolved by a STDP depend on the initial network configuration. Specifically, an initial all-to-all topology evolves to a complex topology. Moreover, external perturbations can induce co-existence of clusters, those whose neurons are synchronous and those whose neurons are desynchronous. This work reveals that STDP based on Hebbian rules leads to a change in the direction of the synapses between high and low frequency neurons, and therefore, Hebbian learning can be explained in terms of preferential attachment between these two diverse communities of neurons, those with low-frequency spiking neurons, and those with higher-frequency spiking neurons.

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Our aim is to unveil how resonances of parametric systems are affected when symmetry is broken. We showed numerically and experimentally that odd resonances indeed come about when the pendulum is excited along a tilted direction. Applying the Melnikov subharmonic function, we not only determined analytically the loci of saddle-node bifurcations delimiting resonance regions in parameter space but also explained these observations by demonstrating that, under the Melnikov method point of view, odd resonances arise due to an extra torque that appears in the asymmetric case.

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INTRODUCTION: The 35delG mutation in the connexin 26 gene is the most common mutation that generates deafness, but its frequency in different countries is strongly based on its ethnicity. Brazilians belong to different ethnic groups. OBJECTIVES: To report the frequency of homo and heterozygosis 35delG mutation in a population with severe to profound bilateral sensorineural deafness, and separate them by ethnicity. METHODS: 100 individuals were studied with severe to profound hearing loss, with no other etiology found, and tested for 35delG mutation. The group presented the following ethnicity distribution: 25% Blacks; 30% Latin Europeans; 26.2% Blacks/Latin Europeans and 2.3% native. RESULTS: The 35delG mutation was found in 20% of patients: 15% were heterozygous and 5% homozygous. All homozygous were of Latin European origin. CONCLUSION: Ethnicity shows marked determination of the presence of the 35delG mutation, and it was only found in homozygosis in the group of Latin Europeans.

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In this work we investigate a mathematical model describing tumour growth under a treatment by chemotherapy that incorporates time-delay related to the conversion from resting to hunting cells. We study the model using values for the parameters according to experimental results and vary some parameters relevant to the treatment of cancer. We find that our model exhibits a dynamical behaviour associated with the suppression of cancer cells, when either continuous or pulsed chemotherapy is applied according to clinical protocols, for a large range of relevant parameters. When the chemotherapy is successful, the predation coefficient of the chemotherapic agent acting on cancer cells varies with the infusion rate of chemotherapy according to an inverse relation. Finally, our model was able to reproduce the experimental results obtained by Michor and collaborators [Nature 435 (2005) 1267] about the exponential decline of cancer cells when patients are treated with the drug glivec.

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OBJECTIVE: Stem cells have the ability to renew themselves and differentiate into various cell types. For this reason, numerous research groups have been studying these cells for their therapeutic potential. Some of the therapies, however, are not producing the expected results because of contamination by other cell types, especially by fibroblasts. In the cosmetic industry, stem cells are used to test the efficacy of anti-ageing and rejuvenation products. The purpose of this work was to gain a better understanding of the differences in phenotype, in gene expression associated with stem cells, in the pattern of cell surface proteins and in the differentiation capacity of adipose-derived stem cells, of skin-derived stem cells and of commercially available fibroblasts. METHODS: In this study, we compared fibroblasts with mesenchymal stem cells derived from bone marrow, skin (dermis) and adipose tissue, to assess the differentiation potential of fibroblasts. Dermal and adipose stem cells were isolated from aesthetic surgery patients, and fibroblasts were obtained from a commercial source. The following parameters were used in this study: immunophenotypic profile (positive: CD29, CD73, CD90 and CD105; negative: CD14, CD45 and HLA-DR); differentiation into osteoblastic, chondrogenic and adipogenic cell types; and PCR array to analyse the gene expression of cells isolated from different culture passages. RESULTS: Fibroblasts express the same cell immunophenotypic markers, as well as the genes that are known to be expressed in stem cells, and were shown to be expressed also in adipose and dermis stem cells. Fibroblasts are also able to differentiate into the three cell lineages mentioned above, that is, adipocytes, osteocytes and chondrocytes. CONCLUSION: Human dermal fibroblasts have a potential to adhere to plastic surfaces and differentiate into other cell types. However, for stem cells intended to be used in cosmetics, experiments conducted with contaminated fibroblasts may produce poor or even falsely negative results for the efficacy of the active ingredient or formulation and thus conceal their promising effects as anti-ageing and skin rejuvenation products.

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The MSH2 c.388_389del mutation has occasionally been described in Lynch families worldwide. At the Portuguese Oncology Institute in Porto, Portugal, we have identified 16 seemingly unrelated families with this germline mutation. To evaluate if this alteration is a founder or a recurrent mutation we performed haplotype analysis in the 16 Portuguese index cases and 55 relatives, as well as in four index cases and 13 relatives reported from Germany, Scotland, England, and Argentina. In the Portuguese families we observed a shared haplotype of approximately 10 Mb and all were originated from the north of Portugal. These results suggest that this alteration is a founder mutation in Portugal with a relatively recent origin. In the reported families outside Portugal with this mutation different haplotype backgrounds were observed, supporting the hypothesis that it occurred de novo on multiple occasions. We also conclude that the high proportion of families with the MSH2 c.388_389del mutation indicates that screening for this alteration as a first step may be cost-effective in the genetic testing of Lynch syndrome suspects of Portuguese ancestry, especially those originating from the north of Portugal.

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INTRODUCTION: The act of swallowing depends on a complex and dynamic process which uses common structures to the act of breathing; respiratory problems can cause swallowing difficulties. AIM: To assess the swallowing pharyngeal phase in patients with chronic cough. METHOD: Retrospective study with 15 patients of both genders, patients with chronic cough and risk factors for aspiration defined by the pneumologic diagnosis. The patients were submitted to anamnesis on complaints related to swallowing, chewing and breathing, or related to food and to videofluoroscopic examination. RESULTS: It was observed that 33.3% had normal and functional swallowing, being the last one of most prevalence. The mild dysphagia was observed in 20% of the patients, the mild to moderate dysphagia in 6.7% of them. In relation to the Rosenbek scale, 73.3% of patients presented degree 1, 6.7% presented degrees 2 and 3, and 13.3% presented degree 8. The most found pathology was the chronic cough with 40%, followed by asthma with 20%; 69.2% of patients presented stasis and of these, five used protection maneuvers, of these, seven were effective and only three were used in the presence of stasis. The most used maneuver was the multiple swallowing, being effective in 100%. CONCLUSION: There are peculiarities in the patients' swallowing with chronic cough that, although not presenting complaints relating to swallowing, it presents an important aspiration risk due to the presence of changes in breathing pattern that can intervene in the coordination between breathing and swallowing, which is essential to protect the lower airway.

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Nowadays, stormwater infiltration systems are frequently used because of their ability to reduce flows and volumes in downstream sewers, decrease overflows in surface waters and make it possible to recharge groundwater. Moreover, they come in various forms with different uses. Despite these advantages the long term sustainability of these systems is questionable and their real performances have to be assessed taking into account various and sometimes conflicting aspects. To address this problem a decision support system is proposed. It is based on a multicriteria method built to help managers to evaluate the performance of an existing infiltration system at different stages of its lifespan and identify whether it performs correctly or not, according to environmental, socio-economic, technical and sanitary aspects. The paper presents successively: the performance indicators and the way they were built, the multicriteria method to identify if the system works properly and a case study.

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BACKGROUND: Periodontal disease is often associated with systemic diseases and is characterized by destruction of the tissues supporting the teeth. Patients using immunosuppressive drugs such as tacrolimus are among those who suffer from tissue destruction. OBJECTIVE: We sought to evaluate the effects of laser and photodynamic therapies (PDT; nonsurgical) as an adjunct to scaling and rootplaning (SRP) in the treatment of corona-induced periodontitis in rats immunosuppressed with tacrolimus (Prograf). MATERIALS AND METHODS: The animals were divided into 5 groups. Each groups had 6 rats. Group I, the control group, received only saline solution throughout the study period of 42 days and did not receive periodontal treatment; group II received saline solution and SRP; group III received tacrolimus (1 mg/kg per day) and was treated with SRP; group IV animals were treated identically to group III and then administered laser treatment; and in group V, the animals were treated identically to group III and then administered PDT. RESULTS: Statistical analysis indicated decreased bone loss with the progression of time (P = .035). There was no difference between the bone loss associated with the types of treatment administered to groups I, II, and III (P > .9) or groups IV and V (P > .6). The analysis also indicated that immunosuppression was not a bone loss-determining factor. CONCLUSION: Laser and PDT therapies were effective as an adjunctive treatment to SRP in reducing bone loss caused by experimental periodontitis induced in animals being treated systemically with tacrolimus.

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