HER2 classification in breast cancer cells: A new explainable machine learning application for immunohistochemistry.

The immunohistochemical (IHC) evaluation of epidermal growth factor 2 (HER2) for the diagnosis of breast cancer is still qualitative with a high degree of inter-observer variability, and thus requires the incorporation of complementary techniques such as fluorescent in situ hybridization (FISH) to resolve the diagnosis. Implementing automatic algorithms to classify IHC biomarkers is crucial for typifying the tumor and deciding on therapy for each patient with better performance. The present study aims to demonstrate that, using an explainable Machine Learning (ML) model for the classification of HER2 photomicrographs, it is possible to determine criteria to improve the value of IHC analysis. We trained a logistic regression-based supervised ML model with 393 IHC microscopy images from 131 patients, to discriminate between upregulated and normal expression of the HER2 protein. Pathologists' diagnoses (IHC only) vs. the final diagnosis complemented with FISH (IHC + FISH) were used as training outputs. Basic performance metrics and receiver operating characteristic curve analysis were used together with an explainability algorithm based on Shapley Additive exPlanations (SHAP) values to understand training differences. The model could discriminate amplified IHC from normal expression with better performance when the training output was the IHC + FISH final diagnosis (IHC vs. IHC + FISH: area under the curve, 0.94 vs. 0.81). This may be explained by the increased analytical impact of the membrane distribution criteria over the global intensity of the signal, according to SHAP value interpretation. The classification model improved its performance when the training input was the final diagnosis, downplaying the weighting of the intensity of the IHC signal, suggesting that to improve pathological diagnosis before FISH consultation, it is necessary to emphasize subcellular patterns of staining.

Synthesis of fluorescent chalcones, photophysical properties, quantitative structure-activity relationship and their biological application.

The development of fluorescent pigments is an area of interest in several research fields due to their high sensitivity. In the current study-eight known and three new N,N-dimethylamino-chalcones (12a-k) were synthesized with good yields using the Claisen-Schmidt reaction. For each molecular system, the photophysical properties, including the maximum absorption wavelength (λAbsorption), molar absorption coefficient (ε), maximum excitation wavelength (λExcitation), maximum emission wavelength (λEmission), Stokes Shift (Δλ), fluorescence quantum yield (Φfl), fluorescence lifetime (τfl), radiative and non-radiative rate constants (kR and kNR, respectively) were evaluated. Variations in each of these properties were analyzed depending on the substituents present on each compound. To relate the chemical structures of the synthesized compounds to their photophysical properties, Hansch analysis (2D-QSPR) was applied. As a result of Hansch analysis, we found different photophysical properties related to molecular orbitals and the energy of their derivatives (Highest Occupied Molecular Orbital-HOMO, Lowest Unoccupied Molecular Orbital-LUMO, Difference between LUMO-HOMO-ΔLH, Chemical potential-µ, Hardness-η, Softness-S, and electrophilic global index-ω) as well as to the atomic charges on atoms C5, Cα, Cß, and CO. The application of this type of analysis has made it possible to understand and subsequently design new molecules with defined photophysical properties. Finally, the compounds were use as fluorescent pigment to get living cell imaging on breast cancer cells, obtaining the compound 12a as promissory alternative.

Estrogen, Cognitive Performance, and Functional Imaging Studies: What Are We Missing About Neuroprotection?

Menopause transition can be interpreted as a vulnerable state characterized by estrogen deficiency with detrimental systemic effects as the low-grade chronic inflammation that appears with aging and partly explains age-related disorders as cancer, diabetes mellitus and increased risk of cognitive impairment. Over the course of a lifetime, estrogen produces several beneficial effects in healthy neurological tissues as well as cardioprotective effects, and anti-inflammatory effects. However, clinical evidence on the efficacy of hormone treatment in menopausal women has failed to confirm the benefit reported in observational studies. Unambiguously, enhanced verbal memory is the most robust finding from longitudinal and cross-sectional studies, what merits consideration for future studies aiming to determine estrogen neuroprotective efficacy. Estrogen related brain activity and functional connectivity remain, however, unexplored. In this context, the resting state paradigm may provide valuable information about reproductive aging and hormonal treatment effects, and their relationship with brain imaging of functional connectivity may be key to understand and anticipate estrogen cognitive protective effects. To go in-depth into the molecular and cellular mechanisms underlying rapid-to-long lasting protective effects of estrogen, we will provide a comprehensive review of cognitive tasks used in animal studies to evaluate the effect of hormone treatment on cognitive performance and discuss about the tasks best suited to the demonstration of clinically significant differences in cognitive performance to be applied in human studies. Eventually, we will focus on studies evaluating the DMN activity and responsiveness to pharmacological stimulation in humans.

Optogenetic control of cancer cell survival in ChR2-transfected HeLa cells.

Optogenetics is a molecular biological technique involving transfection of cells with photosensitive proteins and the subsequent study of their biological effects. The aim of this study was to evaluate the effect of blue light on the survival of HeLa cells, transfected with channelrhodopsin-2 (ChR2). HeLa wild-type cells were transfected with a plasmid that contained the gene for ChR2. Transfection and channel function were evaluated by real-time polymerase chain reaction (RT-PCR), fluorescence imaging using green fluorescent protein (GFP) and flow cytometry for intracellular calcium changes using a Fura Red probe. We developed a platform for optogenetic stimulation for use within the cell culture incubator. Different stimulation procedures using blue light (467 nm) were applied for up to 24 h. Cell survival was determined by flow cytometry using propidium iodide and rhodamine probes. Change in cell survival showed a statistically significant (p < 0.05) inverse association with the frequency and time of application of the light stimulus. This change seemed to be associated with the ChR2 cis-trans-isomerization cycle. Cell death was associated with high concentrations of calcium in the cytoplasm and stimulation intervals less than the period of isomerization. It is possible to transfect HeLa cells with ChR2 and control their survival under blue light stimulation. We suggest that this practice should be considered in the future development of optogenetic systems in biological or biomedical research.

Molecular weight and guluronic/mannuronic ratio of alginate produced by Azotobacter vinelandii at two bioreactor scales under diazotrophic conditions.

Alginates can be used to elaborate hydrogels, and their properties depend on the molecular weight (MW) and the guluronic (G) and mannuronic (M) composition. In this study, the MW and G/M ratio were evaluated in cultures of Azotobacter vinelandii to 3 and 30 L scales at different oxygen transfer rates (OTRs) under diazotrophic conditions. An increase in the maximum OTR (OTRmax) improved the alginate production, reaching 3.3 ± 0.2 g L-1. In the cultures conducted to an OTR of 10.4 mmol L-1 h-1 (500 rpm), the G/M increased during the cell growth phase and decreased during the stationary phase; whereas, in the cultures at 19.2 mmol L-1 h-1 was constant throughout the cultivation. A higher alginate MW (520 ± 43 kDa) and G/M ratio (0.86 ± 0.01) were obtained in the cultures conducted at 10.4 mmol L-1 h-1. The OTR as a criterion to scale up alginate production allowed to replicate the concentration and the alginate production rate; however, it was not possible reproduce the MW and G/M ratio. Under a similar specific oxygen uptake rate (qO2) (approximately 65 mmol g-1 h-1) the alginate MW was similar (approximately 365 kDa) in both scales. The evidences revealed that the qO2 can be a parameter adequate to produce alginate MW similar in two bioreactor scales. Overall, the results have shown that the alginate composition could be affected by cellular respiration, and from a technological perspective the evidences contribute to the design process based on oxygen consumption to produce alginates defined.

Providing first evidence of the behaviour and potential environmental impacts of an accidental underwater release of propane.

Aquaculture activities in southern Chile demand floating devices to produce electricity powered by diesel generators. It has been recently proposed to replace this fuel with propane. However, little is known about the behaviour and possible environmental impacts of an accidental release of propane underwater. In this study we evaluated the impact of water temperature and salinity on the saturation and further release of propane under controlled laboratory experiments. Results showed that under extreme environmentally relevant scenarios (high and low temperature and salinity), propane saturated the water more quickly. However, while it is important to consider that saturation times can be similar (∼2 h), the magnitudes of propane dissolved can be different. Experiments showed that cold waters (5 °C) propane is dissolved twice than warm waters (20 °C). Residence time was more affected by water temperature and almost independent of water salinity. Propane may take at least 2 days to be released from waters (around 90% of the initial amount dissolved under laboratory conditions). Additionally, we evaluated the impact on dissolved oxygen displacement and the embryotoxicity of the dissolved fraction by using Zebrafish Embryo Toxicity Assay. Results showed that dissolved oxygen was quickly removed. However, the levels of dissolved oxygen were promptly recovered in the studied systems. We also observed that propane can generate genotoxic effects (3-10% mortality), but after 2 days the system can be almost free of propane and the effects may become much lower. Comparatively with the literature, propane showed to be less toxic than diesel and it is a viable and less environmentally hazardous replacement for diesel.

Walking performance is associated with coronary artery calcification in very old adults.

BACKGROUND: Coronary artery calcification (CAC) scores have good predictive value for atherosclerosis-related outcomes in the geriatric population. The low availability of cardiac computed tomography is an obstacle to assess CAC in clinical practice. Thus, clinical signs with a good degree of association with CAC can help to estimate cardiovascular risk, particularly in low-income populations. OBJECTIVES: To assess whether clinical, biochemical and functional measures explain the CAC scores in older individuals. METHODS: We characterized 89 non-institutionalized older volunteers (≥ 80 years old) by means of a comprehensive biochemical and anthropometric evaluation along with assessments of CAC scores determined by computerized tomography, and tested their association with walking speed test (WS) and handgrip strength (HS) performance. RESULTS: Analyses of variance showed that body mass index (BMI) and waist circumference (WC) differed significantly (p ≤ 0.01 and p ≤ 0.03; respectively) across quartiles, so that subsequent tests were adjusted for anthropometry. ANCOVA revealed that the two lower quartiles of CAC had better performance in WS compared to the third and fourth quartiles (p ≤ 0.04). Multinomial logistic regression analysis showed that WS scores exhibit enough power (R2 = 0.379, p = 0.05) to explain CAC scores. There were no significant differences for HS between quartiles (p = 0.87). CONCLUSION: WS is associated and explain CAC scores, and may be useful to stratify atherosclerotic burden in apparently healthy very old individuals regardless of body composition.

Respiration in Azotobacter vinelandii and its relationship with the synthesis of biopolymers

Azotobacter vinelandii is a gram-negative soil bacterium that produces two biopolymers of biotechnological interest, alginate and poly(3-hydroxybutyrate), and it has been widely studied because of its capability to fix nitrogen even in the presence of oxygen. This bacterium is characterized by its high respiration rates, which are almost 10-fold higher than those of Escherichia coli and are a disadvantage for fermentation processes. On the other hand, several works have demonstrated that adequate control of the oxygen supply in A. vinelandii cultivations determines the yields and physicochemical characteristics of alginate and poly(3-hydroxybutyrate). Here, we summarize a review of the characteristics of A. vinelandii related to its respiration systems, as well as some of the most important findings on the oxygen consumption rates as a function of the cultivation parameters and biopolymer production.

TRPV1-Estradiol Stereospecific Relationship Underlies Cell Survival in Oxidative Cell Death.

17ß-estradiol is a neuronal survival factor against oxidative stress that triggers its protective effect even in the absence of classical estrogen receptors. The polymodal transient receptor potential vanilloid subtype 1 (TRPV1) channel has been proposed as a steroid receptor implied in tissue protection against oxidative damage. We show here that TRPV1 is sufficient condition for 17ß-estradiol to enhance metabolic performance in injured cells. Specifically, in TRPV1 expressing cells, the application of 17ß-estradiol within the first 3 h avoided H2O2-dependent mitochondrial depolarization and the activation of caspase 3/7 protecting against the irreversible damage triggered by H2O2. Furthermore, 17ß-estradiol potentiates TRPV1 single channel activity associated with an increased open probability. This effect was not observed after the application of 17α-estradiol. We explored the TRPV1-Estrogen relationship also in primary culture of hippocampal-derived neurons and observed that 17ß-estradiol cell protection against H2O2-induced damage was independent of estrogen receptors pathway activation, membrane started and stereospecific. These results support the role of TRPV1 as a 17ß-estradiol-activated ionotropic membrane receptor coupling with mitochondrial function and cell survival.

Acute Pannexin 1 Blockade Mitigates Early Synaptic Plasticity Defects in a Mouse Model of Alzheimer's Disease.

Synaptic loss induced by soluble oligomeric forms of the amyloid ß peptide (sAßos) is one of the earliest events in Alzheimer's disease (AD) and is thought to be the major cause of the cognitive deficits. These abnormalities rely on defects in synaptic plasticity, a series of events manifested as activity-dependent modifications in synaptic structure and function. It has been reported that pannexin 1 (Panx1), a nonselective channel implicated in cell communication and intracellular signaling, modulates the induction of excitatory synaptic plasticity under physiological contexts and contributes to neuronal death under inflammatory conditions. Here, we decided to study the involvement of Panx1 in functional and structural defects observed in excitatory synapses of the amyloid precursor protein (APP)/presenilin 1 (PS1) transgenic (Tg) mice, an animal model of AD. We found an age-dependent increase in the Panx1 expression that correlates with increased Aß levels in hippocampal tissue from Tg mice. Congruently, we also observed an exacerbated Panx1 activity upon basal conditions and in response to glutamate receptor activation. The acute inhibition of Panx1 activity with the drug probenecid (PBN) did not change neurodegenerative parameters such as amyloid deposition or astrogliosis, but it significantly reduced excitatory synaptic defects in the AD model by normalizing long-term potentiation (LTP) and depression and improving dendritic arborization and spine density in hippocampal neurons of the Tg mice. These results suggest a major contribution of Panx1 in the early mechanisms leading to the synaptopathy in AD. Indeed, PBN induced a reduction in the activation of p38 mitogen-activated protein kinase (MAPK), a kinase widely implicated in the early neurotoxic signaling in AD. Our data strongly suggest that an enhanced expression and activation of Panx1 channels contribute to the Aß-induced cascades leading to synaptic dysfunction in AD.

Resistance training and innate immunosenescence of the innate immune system / Entrenamiento de resistencia e inmunosenescencia del sistema inmune innato / Treinamento resistido e imunossenescência do sistema imune inato

Phagocytic cells constitute the first defense line against the diversity of infectious agents. The effects of aging on the immune function - immunosenescence - affect the phagocytic capacity of neutrophils and monocytes/macrophages and result in increased risk to cancer and other diseases. The aim of this review was to assess the functional aspects of the innate system cells in aging. Evidence brought about by this review suggests that resistance training is a useful therapy to mitigate the adverse effects of the innate immune system aging process. Resistance training is consistently recommended as assistent strategy for prevention of the inflamaging and associated chronic diseases, but establishing adequate program is still in demand. In addition, future studies are needed to improve our understanding of the resistance training-induced mechanisms underlying changes in phagocytic activity in the elderly

Las células fagocíticas constituyen la primera línea de defensa contra los agentes infecciosos. Los efectos del envejecimiento sobre la función inmune - inmunosenescencia - afectan la capacidad fagocítica de neutrófilos y monocitos/macrófagos y resultan en riesgo aumentado para el cáncer y otras enfermedades. El objetivo de esta revisión fue evaluar los aspectos funcionales de las células del sistema innato en el envejecimiento. Las evidencias revisadas sugieren que el entrenamiento de resistencia es una terapia útil para atenuar los efectos adversos del proceso de envejecimiento del sistema inmune innato. Se recomienda el entrenamiento de resistencia continuamente como estrategia complementaria para la prevención de la inflamación y de las enfermedades crónicas asociadas, pero hay que establecer el programa adecuado. Además, se necesitan más investigaciones para mejorar nuestra comprensión de los mecanismos modulados por el entrenamiento de resistencia que inducen a los cambios en la actividad fagocítica en las personas mayores

As células fagocitárias constituem a primeira linha de defesa contra agentes infecciosos. Os efeitos do envelhecimento sobre a função imune - imunossenescência - afetam a capacidade fagocítica de neutrófilos e monócitos/macrófagos e resultam em aumento do risco para câncer e outras doenças. O objetivo desta revisão foi avaliar os aspectos funcionais das células do sistema inato durante o envelhecimento. Os estudos revisados sugerem que o treinamento resistido é uma terapia útil para atenuar os efeitos adversos do processo de envelhecimento do sistema imune inato. Recomenda-se que o treinamento resistido seja aplicado continuamente como estratégia complementar para a prevenção da inflamação e doenças crônicas associadas, porém deve-se estabelecer o programa adequado. Ressalta-se ainda que, são necessários mais estudos para melhorar a compreensão sobre os mecanismos modulados pelo treinamento resistido que induzem a alterações na atividade fagocítica em idosos

Evidence for the facultative intracellular behaviour of the fish pathogen Vibrio ordalii.

Vibrio ordalii is an extracellular, Gram-negative bacterium that produces vibriosis in salmonids. While pathogenesis is not fully understood, this bacterium has numerous likely genes for adhesion, colonization, invasion factors and, as recently suggested, intracellular behaviour. Therefore, this study aimed to clarify possible intracellular behaviour for V. ordalii Vo-LM-18 and ATCC 33509T in the fish-cell lines SHK-1 and CHSE-214. Confocal microscopy revealed Vo-LM-18 and ATCC 33509T inside cytoplasm in both fish-cell lines at 4 hr post-inoculation (hpi). At 8 and 16 hpi, the proportion of fish cells invaded by both strains increased. Moreover, intracellular V. ordalii were observed after 8 hpi inside mouse embryonic fibroblasts (MEF), demonstrating that entry was not due to a cellular phagocytosis process. Flow cytometry confirmed immunocytochemistry results, with both V. ordalii evidencing statistically significant differences in the number of infected cells between 8 and 16 hpi. Interestingly, V. ordalii infection did not significantly damage fish cells, as determined by LDH liberation. Viable counts at 8 hpi detected, on average for both lines, 176 ± 47 CFU/ml of culturable intracellular Vo-LM-18 and ATCC 33509T cells. These in vitro findings support the facultative intracellular behaviour of V. ordalii and may be of importance for understanding pathogenicity and survival in aquatic environments.

Default Mode Network, Meditation, and Age-Associated Brain Changes: What Can We Learn from the Impact of Mental Training on Well-Being as a Psychotherapeutic Approach?

Aging is a physiological process accompanied by cognitive decline, principally in memory and executive functions. Alterations in the connectivity of the default mode network (DMN) have been found to participate in cognitive decline, as well as in several neurocognitive disorders. The DMN has antisynchronic activity with attentional networks (task-positive networks (TPN)), which are critical to executive function and memory. Findings pointing to the regulation of the DMN via activation of TPN suggest that it can be used as a strategy for neuroprotection. Meditation is a noninvasive and nonpharmacological technique proven to increase meta-awareness, a cognitive ability which involves the control of both networks. In this review, we discuss the possibility of facilitating healthy aging through the regulation of networks through meditation. We propose that by practicing specific types of meditation, cognitive decline could be slowed, promoting a healthy lifestyle, which may enhance the quality of life for the elderly.

Poly(3-hydroxybutyrate) accumulation by Azotobacter vinelandii under different oxygen transfer strategies.

Azotobacter vinelandii OP is a bacterium that produces poly(3-hydroxybutyrate) (PHB). PHB production in a stirred bioreactor, at different oxygen transfer strategies, was evaluated. By applying different oxygen contents in the inlet gas, the oxygen transfer rate (OTR) was changed under a constant agitation rate. Batch cultures were performed without dissolved oxygen tension (DOT) control (using 9% and 21% oxygen in the inlet gas) and under DOT control (4%) using gas blending. The cultures that developed without DOT control were limited by oxygen. As result of varying the oxygen content in the inlet gas, a lower OTR (4.6 mmol L-1 h-1) and specific oxygen uptake rate (11.6 mmol g-1 h-1) were obtained using 9% oxygen in the inlet gas. The use of 9% oxygen in the inlet gas was the most suitable for improving the intracellular PHB content (56 ± 6 w w-1). For the first time, PHB accumulation in A. vinelandii OP cultures, developed with different OTRs, was compared under homogeneous mixing conditions, demonstrating that bacterial respiration affects PHB synthesis. These results can be used to design new oxygen transfer strategies to produce PHB under productive conditions.

Intracellular aggregated TRPV1 is associated with lower survival in breast cancer patients.

BACKGROUND: Breast cancer is a malignant disease that represents an important public health burden. The description of new molecular markers can be important to diagnosis, classification, and treatment. Transient receptor potential vanilloid 1 (TRPV1) polymodal channel is expressed in different neoplastic tissues and cell lines of breast cancer and associated with the regulation of tumor growth, tumor neurogenesis, cancer pain, and malignant progression of cancer. In primary and metastatic breast cancer tumors, TRPV1 is expressed during neoplastic transformation, invasive behavior, and resistance to cytotoxic therapy. OBJECTIVE: The objective of this study was to describe the subcellular distribution of TRPV1 in invasive breast carcinomas and its association with survival. METHODS: In 33 cases of invasive breast carcinomas, we identified immunohistochemical and immunofluorescent expression patterns of TRPV1 compared to healthy breast tissue. We characterized the expression of TRPV1 induced by estrogens in breast cancer cell lines MCF-7 and MDA to establish a model of the TRPV1-estrogen relationship regarding the malignant potential. We examined the association of TRPV1 patterns with patients' survival with the Kaplan-Meyer model, using the log-rank test at 5 years of follow-up. The relation of TRPV1 expression patterns to the St. Gallen breast cancer subtypes was also tested. RESULTS: Based on immunohistochemical expression pattern of TRPV1, we distinguished two main categories of breast cancer tissue, a "classical category" that exhibited diffuse expression of the channel and a "non-classical category" that expressed the channel in aggregates at the ER/Golgi and/or surrounding these structures. The classical pattern of TRPV1 was associated with a higher survival rate. In breast cancer cell lines, increasing doses of estrogens induced increased TRPV1 expression with nonclassical patterns at higher doses via a mechanism dependent on ER α. CONCLUSION: The expression and distribution of TRPV1 in invasive breast carcinomas may be considered as a biomarker for prognosis of the disease and a probable therapeutic target.

Suggestions for Judo Training with Pacing Strategy and Decision Making by Judo Championship Phases.

The present study aimed to compare pacing and decision making of athletes competing in judo, with particular attention paid to effort-pause ratios occurring in the championship phases of the Olympic Games and non-Olympic Games. The sample was composed of 53,403 sequential actions analyzed during 611 performances of the non-Olympic Games (eliminatory n = 330, quarterfinals n = 60, semi-final n = 88, repechage n = 21, third place playoff n = 26, and final n = 79) and 163 from the Olympic Games (eliminatory n = 71, quarterfinals n = 13, semi-final n = 26, repechage n = 20, third place playoff n = 24, and final n = 14). The analysis of effort-pause ratios included separating bouts into states of approach, gripping, attack, groundwork and pause, according to frequency and time. A Markov multi-state model and analysis of variance were applied (p ≤ 0.05). Approach time presented differences of the eliminatory Olympic Games (7.3 ± 3.2 s) versus final non-Olympic Games (6.0 ± 2.2s), and the third place playoff Olympic Games (8.1 ± 2.3 s) versus semi-final (6.2 ± 2.4 s) and third place playoff (5.9 ± 2.1 s) of the non-Olympic Games, and the semi-final Olympic Games (8.6 ± 2.3 s) versus eliminatory (6.5 ± 2.3 s), quarter-finals (6.5 ± 1.7 s), semi-final (6.2 ± 2.4 s), repechage (6.2 ± 2.2 s), third place playoff (5.9 ± 2.1 s), and final (6.0 ± 2.0 s) of the non-Olympic Games. Pause time presented differences of the semi-final Olympic Games (6.8 ± 2.1 s) versus eliminatory (5.1 ± 3.1 s). The present data suggest a focus on pacing strategy during championship phases, which mimic the requirements of judo combats.

The rs4430796 SNP of the HNF1ß gene associates with type 2 diabetes in older adults.

INTRODUCTION: The impact of type 2 diabetes mellitus raises interest in understanding its evolutionary-genetic basis, to unveil yet unknown pathways that may have immediate medical relevance. The HNF1ß gene (hepatocyte nuclear factor-1 beta) is a transcription factor expressed in tissues such as liver, kidney, genital tract and pancreas that is known to be essential for insulin secretion and glucose balance. We tested the association of allelic variants produced by the HNF1ß gene (rs4430796) variation with the clinical and biochemical profile of elderly Brazilian outpatients with metabolic disorders. MATERIAL AND METHODS: Anthropometry, blood pressure, glycaemia, lipemia and other parameters were assessed in 184 Brazilians aged 60 or older in clinical care settings. Alleles were determined by amplification of the polymorphic site by real time polymerase chain reaction. RESULTS: Analysing variables across the genotypes, a statistically significant difference was noticed in the allele frequencies among diabetic patients, with 30.8% of the A homozygous bearing the condition compared to a prevalence of 12.2% between G homozygotes. CONCLUSION: Our results corroborate the possible protective property of the GG genotype from the rs4430796 variation (already presented in the literature) against occurrence of diabetes mellitus, which appears applicable to elderly individuals as well, even in the context of multiple metabolic disorders so typical in older Brazilians.

Proteostasis and Mitochondrial Role on Psychiatric and Neurodegenerative Disorders: Current Perspectives.

Proteostasis involves processes that are fundamental for neural viability. Thus, protein misfolding and the formation of toxic aggregates at neural level, secondary to dysregulation of the conservative mechanisms of proteostasis, are associated with several neuropsychiatric conditions. It has been observed that impaired mitochondrial function due to a dysregulated proteostasis control system, that is, ubiquitin-proteasome system and chaperones, could also have effects on neurodegenerative disorders. We aimed to critically analyze the available findings regarding the neurobiological implications of proteostasis on the development of neurodegenerative and psychiatric diseases, considering the mitochondrial role. Proteostasis alterations in the prefrontal cortex implicate proteome instability and accumulation of misfolded proteins. Altered mitochondrial dynamics, especially in proteostasis processes, could impede the normal compensatory mechanisms against cell damage. Thereby, altered mitochondrial functions on regulatory modulation of dendritic development, neuroinflammation, and respiratory function may underlie the development of some psychiatric conditions, such as schizophrenia, being influenced by a genetic background. It is expected that with the increasing evidence about proteostasis in neuropsychiatric disorders, new therapeutic alternatives will emerge.