The leaf idioblastome of the medicinal plant Catharanthus roseus is associated with stress resistance and alkaloid metabolism.

Catharanthus roseus leaves produce a range of monoterpenoid indole alkaloids (MIAs) that include low levels of the anticancer drugs vinblastine and vincristine. The MIA pathway displays a complex architecture spanning different subcellular and cell type localizations, and is under complex regulation. As a result, the development of strategies to increase the levels of the anticancer MIAs has remained elusive. The pathway involves mesophyll specialized idioblasts where the late unsolved biosynthetic steps are thought to occur. Here, protoplasts of C. roseus leaf idioblasts were isolated by fluorescence-activated cell sorting, and their differential alkaloid and transcriptomic profiles were characterized. This involved the assembly of an improved C. roseus transcriptome from short- and long-read data, IDIO+. It was observed that C. roseus mesophyll idioblasts possess a distinctive transcriptomic profile associated with protection against biotic and abiotic stresses, and indicative that this cell type is a carbon sink, in contrast to surrounding mesophyll cells. Moreover, it is shown that idioblasts are a hotspot of alkaloid accumulation, suggesting that their transcriptome may hold the key to the in-depth understanding of the MIA pathway and the success of strategies leading to higher levels of the anticancer drugs.

IL-4 shapes microglia-dependent pruning of the cerebellum during postnatal development.

Interleukin-4 (IL-4) is a type 2 cytokine with pleiotropic functions in adaptive immunity, allergies, and cognitive processes. Here, we show that low levels of IL-4 in the early postnatal stage delineate a critical period in which microglia extensively prune cerebellar neurons. Elevating the levels of this cytokine via peripheral injection, or using a mouse model of allergic asthma, leads to defective pruning, permanent increase in cerebellar granule cells, and circuit alterations. These animals also show a hyperkinetic and impulsive-like phenotype, reminiscent of attention-deficit hyperactivity disorder (ADHD). These alterations are blocked in Il4rαfl/fl::Cx3cr1-CreER mice, which are deficient in IL-4 receptor signaling in microglia. These findings demonstrate a previously unknown role for IL-4 during a neuroimmune critical period of cerebellar maturation and provide a first putative mechanism for the comorbidity between allergic disease and ADHD observed in humans.

The physical and psychological effects of occupational noise among seafarers: a systematic review.

The aims were to highlight noise levels on board and the health effects of noise on seafarers. Data was collected from multiple databases: PubMed, Web of Science, Scopus, and Ebsco Host. Initially, the search resulted in a total of 197 articles, 16 were chosen. Several ships were found which most sailors had noise-induced hearing loss (NIHL) (n = 6). The engine room has been defined as having the highest level of noise. In addition, noise exposure was associated with hearing loss, tinnitus, sleep disturbances, communication difficulties, poor concentration, dizziness, depression, anxiety, headache, fatigue, and stress. Noise exposure is not the only factor that causes health problems: the duration of exposure while working, years of career as a maritime worker, age, lifestyle habits (smoking, alcohol consumption), and even hobbies related to loud sound (such as concert/disco attendance, listen to loud music, etc.) were associated with the adverse health effects experienced by seafarers.

Exploring the Applicability of Physiological Monitoring to Manage Physical Fatigue in Firefighters.

Physical fatigue reduces productivity and quality of work while increasing the risk of injuries and accidents among safety-sensitive professionals. To prevent its adverse effects, researchers are developing automated assessment methods that, despite being highly accurate, require a comprehensive understanding of underlying mechanisms and variables' contributions to determine their real-life applicability. This work aims to evaluate the performance variations of a previously developed four-level physical fatigue model when alternating its inputs to have a comprehensive view of the impact of each physiological variable on the model's functioning. Data from heart rate, breathing rate, core temperature and personal characteristics from 24 firefighters during an incremental running protocol were used to develop the physical fatigue model based on an XGBoosted tree classifier. The model was trained 11 times with different input combinations resulting from alternating four groups of features. Performance measures from each case showed that heart rate is the most relevant signal for estimating physical fatigue. Breathing rate and core temperature enhanced the model when combined with heart rate but showed poor performance individually. Overall, this study highlights the advantage of using more than one physiological measure for improving physical fatigue modelling. The findings can contribute to variables and sensor selection in occupational applications and as the foundation for further field research.

NatB Catalytic Subunit Depletion Disrupts DNA Replication Initiation Leading to Senescence in MEFs.

Alpha-aminoterminal acetyltransferase B (NatB) is a critical enzyme responsible for acetylating the aminoterminal end of proteins, thereby modifying approximately 21% of the proteome. This post-translational modification impacts protein folding, structure, stability, and interactions between proteins which, in turn, play a crucial role in modulating several biological functions. NatB has been widely studied for its role in cytoskeleton function and cell cycle regulation in different organisms, from yeast to human tumor cells. In this study, we aimed to understand the biological importance of this modification by inactivating the catalytic subunit of the NatB enzymatic complex, Naa20, in non-transformed mammal cells. Our findings demonstrate that depletion of NAA20 results in decreased cell cycle progression and DNA replication initiation, ultimately leading to the senescence program. Furthermore, we have identified NatB substrates that play a role in cell cycle progression, and their stability is compromised when NatB is inactivated. These results underscore the significance of N-terminal acetylation by NatB in regulating cell cycle progression and DNA replication.

Pregnancy and working conditions in the hospital sector: a scoping review.

The different areas and work environments in the hospital sector have a complex set of occupational risk factors that can negatively impact the health of pregnant workers. Illness among this workforce results in sick leave due to work-related diseases and pregnancy, with high absenteeism. The main objective of this study was to review the available literature on the gestational and occupational risks to which pregnant health workers are exposed, causes of absenteeism, and issues related to maternity protection and work in the hospital sector. The authors used online databases to identify papers published in English from 2015 to 2020, based on the PRISMA Extension for Scoping Reviews and three steps of Snowballing. The study reviewed 18 peer-reviewed scientific articles that address pregnancy, work, absenteeism, and maternity protection. Most studies used a quantitative approach (12) and cohort studies in particular (6). The distribution of articles by themes was as follows: pregnancy, health and safety at work (11); pregnancy, health conditions, and absenteeism (13); and work and maternity protection (10). Some inferences were possible from the themes raised. However, the results revealed a gap and the need for specific studies for healthcare workers in the hospital sector, focusing on maternity. This review contributes to more in-depth studies on developing programs, actions, and legislation to protect maternity in hospital working environments.

As diferentes áreas e ambientes de trabalho do setor hospitalar apresentam uma complexidade de fatores de risco que podem impactar negativamente a saúde das trabalhadoras grávidas. O adoecimento dessa força de trabalho resulta em afastamentos por doenças relacionadas ao trabalho e à gravidez, com alto absenteísmo. O objetivo principal deste estudo foi revisar a literatura disponível sobre os riscos gestacionais e ocupacionais a que estão expostas as trabalhadoras de saúde grávidas, causas de absenteísmo e questões relacionadas à proteção da maternidade e do trabalho no setor hospitalar. Bases de dados online foram usadas para identificar artigos em inglês publicados de 2015 a 2020, com base no PRISMA Extension for Scoping Reviews e três etapas de snowballing. Este estudo incluiu 18 artigos científicos revisados por pares que abordam questões relativas à gravidez, absenteísmo e proteção à maternidade no trabalho. A maioria dos estudos utilizou abordagem quantitativa (12), com ênfase nos estudos de coorte (6). Distribuição dos artigos por temas: gravidez, saúde e segurança no trabalho (11); gravidez, intercorrências e absenteísmo (13); e proteção ao trabalho e maternidade (10). Algumas inferências foram possíveis a partir dos temas levantados. No entanto, os resultados evidenciaram a lacuna e a necessidade de estudos específicos para trabalhadores de saúde do setor hospitalar, com enfoque na maternidade. Esta revisão pode contribuir para estudos mais aprofundados sobre o desenvolvimento de programas, ações e legislações de proteção à maternidade no ambiente de trabalho do setor hospitalar.

Lactoferrin perturbs intracellular trafficking, disrupts cholesterol-rich lipid rafts and inhibits glycolysis of highly metastatic cancer cells harbouring plasmalemmal V-ATPase.

The milk-derived bovine lactoferrin (bLf) is an iron-binding glycoprotein with remarkable selective anticancer activity towards highly metastatic cancer cells displaying the proton pump V-ATPase at the plasma membrane. As studies aiming to dissect the bLf mechanisms of action are critical to improve its efficacy and boost its targeted clinical use, herein we sought to further uncover the molecular basis of bLf anticancer activity. We showed that bLf co-localizes with V-ATPase and cholesterol-rich lipid rafts at the plasma membrane of highly metastatic cancer cells. Our data also revealed that bLf perturbs cellular trafficking, induces intracellular accumulation of cholesterol and lipid rafts disruption, downregulates PI3K, and AKT or p-AKT and inhibits glycolysis of cancer cells harbouring V-ATPase at the plasma membrane lipid rafts. Altogether, our results can lay the foundation for future bLf-based targeted anticancer strategies as they unravel a novel cascade of molecular events that explains and further reinforces bLf selectivity for cancer cells displaying plasmalemmal V-ATPase.

Microglia-dependent remodeling of neuronal circuits.

Microglia are tissue-resident macrophages responsible for the surveillance, neuronal support, and immune defense of the brain parenchyma. Recently, the role played by microglia in the formation and function of neuronal circuits has garnered substantial attention. During development, microglia have been shown to engulf neuronal precursors and participate in pruning mechanisms while, in the mature brain, they influence synaptic signaling, provide trophic support and shape synaptic plasticity. Recently, studies have unveiled different microglial characteristics associated with specific brain regions. This emerging view suggests that the maturation and function of distinct neuronal circuits may be potentially associated with the molecular identity microglia adopts across the brain. Here, we review and summarize the known role of these cells in the thalamus, hippocampus, cortex, and cerebellum. We focus on in vivo studies to highlight the characteristics of microglia that may be important in the remodeling of these neuronal circuits and in relation to neurodevelopmental and neuropsychiatric disorders.

Efficient spatially targeted gene editing using a near-infrared activatable protein-conjugated nanoparticle for brain applications.

Spatial control of gene expression is critical to modulate cellular functions and deconstruct the function of individual genes in biological processes. Light-responsive gene-editing formulations have been recently developed; however, they have shown limited applicability in vivo due to poor tissue penetration, limited cellular transfection and the difficulty in evaluating the activity of the edited cells. Here, we report a formulation composed of upconversion nanoparticles conjugated with Cre recombinase enzyme through a photocleavable linker, and a lysosomotropic agent that facilitates endolysosomal escape. This formulation allows in vitro spatial control in gene editing after activation with near-infrared light. We further demonstrate the potential of this formulation in vivo through three different paradigms: (i) gene editing in neurogenic niches, (ii) gene editing in the ventral tegmental area to facilitate monitoring of edited cells by precise optogenetic control of reward and reinforcement, and (iii) gene editing in a localized brain region via a noninvasive administration route (i.e., intranasal).

TARGETing Transcriptional Regulation in the Medicinal Plant Catharanthus roseus.

Transcriptional regulation is a central piece of the highly valuable monoterpenoid indole alkaloid pathway of C. roseus , and the ultimate tool for its understanding and manipulation. Here, we describe the adaptation of the TARGET methodology to identify specific and genome-wide leaf targets of C. roseus candidate transcription factors (TFs).

Isolation of Specialized Plant Cells by Fluorescence-Activated Cell Sorting.

Plant organs are built of different cell types, characterized by specific transcription programs and metabolic profiles. The possibility of isolation of such cell types to perform differential transcriptomic, proteomic and metabolomic analyses is highly important to understand many aspects of plant physiology, namely, the structure and regulation of economically valuable specialized metabolic pathways. Here, we describe the isolation of idioblast leaf protoplasts of the medicinal plant Catharanthus roseus by fluorescence-activated cell sorting, taking advantage of the differential autofluorescence properties of those specialized cells.

Acetic acid triggers cytochrome c release in yeast heterologously expressing human Bax.

Proteins of the Bcl-2 protein family, including pro-apoptotic Bax and anti-apoptotic Bcl-xL, are critical for mitochondrial-mediated apoptosis regulation. Since yeast lacks obvious orthologs of Bcl-2 family members, heterologous expression of these proteins has been used to investigate their molecular and functional aspects. Active Bax is involved in the formation of mitochondrial outer membrane pores, through which cytochrome c (cyt c) is released, triggering a cascade of downstream apoptotic events. However, when in its inactive form, Bax is largely cytosolic or weakly bound to mitochondria. Given the central role of Bax in apoptosis, studies aiming to understand its regulation are of paramount importance towards its exploitation as a therapeutic target. So far, studies taking advantage of heterologous expression of human Bax in yeast to unveil regulation of Bax activation have relied on the use of artificial mutated or mitochondrial tagged Bax for its activation, rather than the wild type Bax (Bax α). Here, we found that cell death could be triggered in yeast cells heterologoulsy expressing Bax α with concentrations of acetic acid that are not lethal to wild type cells. This was associated with Bax mitochondrial translocation and cyt c release, closely resembling the natural Bax function in the cellular context. This regulated cell death process was reverted by co-expression with Bcl-xL, but not with Bcl-xLΔC, and in the absence of Rim11p, the yeast ortholog of mammalian GSK3ß. This novel system mimics human Bax α regulation by GSK3ß and can therefore be used as a platform to uncover novel Bax regulators and explore its therapeutic modulation.

Machine Learning Approach to Model Physical Fatigue during Incremental Exercise among Firefighters.

Physical fatigue is a serious threat to the health and safety of firefighters. Its effects include decreased cognitive abilities and a heightened risk of accidents. Subjective scales and, recently, on-body sensors have been used to monitor physical fatigue among firefighters and safety-sensitive professionals. Considering the capabilities (e.g., noninvasiveness and continuous monitoring) and limitations (e.g., assessed fatiguing tasks and models validation procedures) of current approaches, this study aimed to develop a physical fatigue prediction model combining cardiorespiratory and thermoregulatory measures and machine learning algorithms within a firefighters' sample. Sensory data from heart rate, breathing rate and core temperature were recorded from 24 participants during an incremental running protocol. Various supervised machine learning algorithms were examined using 21 features extracted from the physiological variables and participants' characteristics to estimate four physical fatigue conditions: low, moderate, heavy and severe. Results showed that the XGBoosted Trees algorithm achieved the best outcomes with an average accuracy of 82% and accuracies of 93% and 86% for recognising the low and severe levels. Furthermore, this study evaluated different methods to assess the models' performance, concluding that the group cross-validation method presents the most practical results. Overall, this study highlights the advantages of using multiple physiological measures for enhancing physical fatigue modelling. It proposes a promising health and safety management tool and lays the foundation for future studies in field conditions.

Applicability of Physiological Monitoring Systems within Occupational Groups: A Systematic Review.

The emergence of physiological monitoring technologies has produced exceptional opportunities for real-time collection and analysis of workers' physiological information. To benefit from these safety and health prognostic opportunities, research efforts have explored the applicability of these devices to control workers' wellbeing levels during occupational activities. A systematic review is proposed to summarise up-to-date progress in applying physiological monitoring systems for occupational groups. Adhering with the PRISMA Statement, five databases were searched from 2014 to 2021, and 12 keywords were combined, concluding with the selection of 38 articles. Sources of risk of bias were assessed regarding randomisation procedures, selective outcome reporting and generalisability of results. Assessment procedures involving non-invasive methods applied with health and safety-related goals were filtered. Working-age participants from homogeneous occupational groups were selected, with these groups primarily including firefighters and construction workers. Research objectives were mainly directed to assess heat stress and physiological workload demands. Heart rate related variables, thermal responses and motion tracking through accelerometry were the most common approaches. Overall, wearable sensors proved to be valid tools for assessing physiological status in working environments. Future research should focus on conducting sensor fusion assessments, engaging wearables in real-time evaluation methods and giving continuous feedback to workers and practitioners.

Modeling Energy Expenditure Estimation in Occupational Context by Actigraphy: A Multi Regression Mixed-Effects Model.

The accurate prediction of energy requirements for healthy individuals has many useful applications. The occupational perspective has also been proven to be of great utility for improving workers' ergonomics, safety, and health. This work proposes a statistical regression model based on actigraphy and personal characteristics to estimate energy expenditure and cross-validate the results with reference standardized methods. The model was developed by hierarchical mixed-effects regression modeling based on the multitask protocol data. Measurements combined actigraphy, indirect calorimetry, and other personal and lifestyle information from healthy individuals (n = 50) within the age of 29.8 ± 5 years old. Results showed a significant influence of the variables related to movements, heart rate and anthropometric variables of body composition for energy expenditure estimation. Overall, the proposed model showed good agreement with energy expenditure measured by indirect calorimetry and evidenced a better performance than the methods presented in the international guidelines for metabolic rate assessment proving to be a reliable alternative to normative guidelines. Furthermore, a statistically significant relationship was found between daily activity and energy expenditure, which raised the possibility of further studies including other variables, namely those related to the subject's lifestyle.

Non-Invasive Physiological Monitoring for Physical Exertion and Fatigue Assessment in Military Personnel: A Systematic Review.

During operational activities, military personnel face extremely demanding circumstances, which when combined lead to severe fatigue, influencing both their well-being and performance. Physical exertion is the main condition leading to fatigue, and its continuous tracking would help prevent its effects. This review aimed to investigate the up-to-date progress on non-invasive physiological monitoring to evaluate situations of physical exertion as a pre-condition to fatigue in military populations, and determine the potential associations between physiological responses and fatigue, which can later result in decision-making indicators to prevent health-related consequences. Adhering to the PRISMA Statement, four databases (Scopus, Science Direct, Web of Science and PubMed) were used for a literature search based on combinations of keywords. The eligibility criteria focused on studies monitoring physiological variables through non-invasive objective measurements, with these measurements being developed in military field, combat, or training conditions. The review process led to the inclusion of 20 studies. The findings established the importance of multivariable assessments in a real-life context to accurately characterise the effects of military practices. A tendency for examining heart rate variables, thermal responses, and actigraphy measurements was also identified. The objectives and experimental protocols were diverse, but the effectiveness of non-invasive measurements in identifying the most fatigue-inducing periods was demonstrated. Nevertheless, no assessment system for standardised application was presented. Future work may include the development of assessment methods to translate physiological recordings into actionable information in real-time and mitigate the effects of fatigue on soldiers' performance accurately.

Subfunctionalization of Paralog Transcription Factors Contributes to Regulation of Alkaloid Pathway Branch Choice in Catharanthus roseus.

Catharanthus roseus produces a diverse range of specialized metabolites of the monoterpenoid indole alkaloid (MIA) class in a heavily branched pathway. Recent great progress in identification of MIA biosynthesis genes revealed that the different pathway branch genes are expressed in a highly cell type- and organ-specific and stress-dependent manner. This implies a complex control by specific transcription factors (TFs), only partly revealed today. We generated and mined a comprehensive compendium of publicly available C. roseus transcriptome data for MIA pathway branch-specific TFs. Functional analysis was performed through extensive comparative gene expression analysis and profiling of over 40 MIA metabolites in the C. roseus flower petal expression system. We identified additional members of the known BIS and ORCA regulators. Further detailed study of the ORCA TFs suggests subfunctionalization of ORCA paralogs in terms of target gene-specific regulation and synergistic activity with the central jasmonate response regulator MYC2. Moreover, we identified specific amino acid residues within the ORCA DNA-binding domains that contribute to the differential regulation of some MIA pathway branches. Our results advance our understanding of TF paralog specificity for which, despite the common occurrence of closely related paralogs in many species, comparative studies are scarce.

Effect of Rest Interval Between Sets in the Muscle Function During a Sequence of Strength Training Exercises for the Upper Body.

ABSTRACT: Matos, F, Ferreira, B, Guedes, J, Saavedra, F, Reis, VM, and Vilaça-Alves, J. Effect of rest interval between sets in the muscle function during a sequence of strength training exercises for the upper body. J Strength Cond Res 35(6): 1628-1635, 2021-The objective of this study was to observe the ideal recovery time between sets and exercises, for both chest and back, which allowed for maintaining muscle function with the initial load previously established. Sixty young men recreationally trained in strength training (ST) were divided into 2 groups: (a) 30 subjects were included in the GC group (the group that performed ST for the chest) and (b) 30 subjects were included in the GB group (the group that performed ST for the back). Each group was submitted to 3 experimental sessions, performing an ST sequence with 3 sets of 8 repetition maximum: GC performed a chest barbell press (CBP), an inclined CBP, and a chest butterfly; GB performed a lat pull-down, a back row, and a shoulder extension on the high pulley. The experimental sessions differed in rest time between sets performed (60, 90, and 120 seconds). For both groups in each sequence, significantly higher numbers of repetitions were observed with the rest time of 120 seconds relative to the rest time of 90 seconds (p = 0.004), 120 seconds in relation to the rest time of 60 seconds (p = 0.001), and in the rest interval of 90 seconds in relation to the rest time of 60 seconds (p < 0.0001). The results showed that 120 seconds was sufficient to maintain muscle function and perform the total number of repetitions per set. The data seem to show that for the ST methodology applied, it is not appropriate to assume that a certain relative intensity will translate into a similar number of repetitions in different exercises, especially with shorter rest intervals such as 60 and 90 seconds.

The old guard: Age-related changes in microglia and their consequences.

Among all major organs, the brain is one of the most susceptible to the inexorable effects of aging. Throughout the last decades, several studies in human cohorts and animal models have revealed a plethora of age-related changes in the brain, including reduced neurogenesis, oxidative damage, mitochondrial dysfunction and cell senescence. As the main immune effectors and first responders of the nervous tissue, microglia are at the center of these events. These cells experience irrevocable changes as a result from cumulative exposure to environmental triggers, such as stress, infection and metabolic dysregulation. The age-related immunosenescent phenotype acquired by microglia is characterized by profound modifications in their transcriptomic profile, secretome, morphology and phagocytic activity, which compromise both their housekeeping and defensive functions. As a result, aged microglia are no longer capable of establishing effective immune responses and sustaining normal synaptic activity, directly contributing to age-associated cognitive decline and neurodegeneration. This review discusses how lifestyle and environmental factors drive microglia dysfunction at the molecular and functional level, also highlighting possible interventions to reverse aging-associated damage to the nervous and immune systems.