Device-measured physical activity and cardiometabolic health: the Prospective Physical Activity, Sitting, and Sleep (ProPASS) consortium.

BACKGROUND AND AIMS: Physical inactivity, sedentary behaviour (SB), and inadequate sleep are key behavioural risk factors of cardiometabolic diseases. Each behaviour is mainly considered in isolation, despite clear behavioural and biological interdependencies. The aim of this study was to investigate associations of five-part movement compositions with adiposity and cardiometabolic biomarkers. METHODS: Cross-sectional data from six studies (n = 15 253 participants; five countries) from the Prospective Physical Activity, Sitting and Sleep consortium were analysed. Device-measured time spent in sleep, SB, standing, light-intensity physical activity (LIPA), and moderate-vigorous physical activity (MVPA) made up the composition. Outcomes included body mass index (BMI), waist circumference, HDL cholesterol, total:HDL cholesterol ratio, triglycerides, and glycated haemoglobin (HbA1c). Compositional linear regression examined associations between compositions and outcomes, including modelling time reallocation between behaviours. RESULTS: The average daily composition of the sample (age: 53.7 ± 9.7 years; 54.7% female) was 7.7 h sleeping, 10.4 h sedentary, 3.1 h standing, 1.5 h LIPA, and 1.3 h MVPA. A greater MVPA proportion and smaller SB proportion were associated with better outcomes. Reallocating time from SB, standing, LIPA, or sleep into MVPA resulted in better scores across all outcomes. For example, replacing 30 min of SB, sleep, standing, or LIPA with MVPA was associated with -0.63 (95% confidence interval -0.48, -0.79), -0.43 (-0.25, -0.59), -0.40 (-0.25, -0.56), and -0.15 (0.05, -0.34) kg/m2 lower BMI, respectively. Greater relative standing time was beneficial, whereas sleep had a detrimental association when replacing LIPA/MVPA and positive association when replacing SB. The minimal displacement of any behaviour into MVPA for improved cardiometabolic health ranged from 3.8 (HbA1c) to 12.7 (triglycerides) min/day. CONCLUSIONS: Compositional data analyses revealed a distinct hierarchy of behaviours. Moderate-vigorous physical activity demonstrated the strongest, most time-efficient protective associations with cardiometabolic outcomes. Theoretical benefits from reallocating SB into sleep, standing, or LIPA required substantial changes in daily activity.

Macrophage fate: to kill or not to kill?

Macrophages are dynamic innate immune cells that either reside in tissue, serving as sentinels, or recruited as monocytes from bone marrow into inflamed and infected tissue. In response to cues in the tissue microenvironment (TME), macrophages polarize on a continuum toward M1 or M2 with diverse roles in progression and resolution of disease. M1-like macrophages exhibit proinflammatory functions with antimicrobial and anti-tumorigenic activities, while M2-like macrophages have anti-inflammatory functions that generally resolve inflammatory responses and orchestrate a tissue healing process. Given these opposite phenotypes, proper spatiotemporal coordination of macrophage polarization in response to cues within the TME is critical to effectively resolve infectious disease and regulate wound healing. However, if this spatiotemporal coordination becomes disrupted due to persistent infection or dysregulated coagulation, macrophages' inappropriate response to these cues will result in the development of diseases with clinically unfavorable outcomes. Since plasticity and heterogeneity are hallmarks of macrophages, they are attractive targets for therapies to reprogram toward specific phenotypes that could resolve disease and favor clinical prognosis. In this review, we discuss how basic science studies have elucidated macrophage polarization mechanisms in TMEs during infections and inflammation, particularly coagulation. Therefore, understanding the dynamics of macrophage polarization within TMEs in diseases is important in further development of targeted therapies.

Physical fitness trends in a nationally representative sample of Portuguese youth: What has changed from 2008 to 2018?

This investigation aimed to describe the current physical fitness (PF) status of Portuguese youth, compare secular trends from 2008 and 2018, and establish updated age- and sex-specific percentile values for distinct PF tests. In 2008 and 2018, 22 048 and 8960 children and adolescents (10-18 years) were included in two national cross-sectional investigations. PF was evaluated using the FITESCOLA® battery tests and the handgrip strength test. Independent sample t-tests and chi-squared tests were used to model the results. Weight smoothed percentile values were calculated using Cole's Lambda-Mu-Sigma (LMS) method. All analyses were weighted according to age, sex, and geographic region. In 2018, boys surpassed girls in the 20-m shuttle run, curl-ups, push-ups, standing long, and vertical jump tests, while girls performed better in the sit-and-reach (p < 0.05). The percentage of boys and girls meeting the healthy zone in the 20-min shuttle run test did not differ between 2008 and 2018 (p ≥ 0.05). In boys, a higher percentage fell in the healthy zone for the curl-up and push-up tests in 2018 compared to 2008 (85.8% vs. 83.4%, and 57.8% vs. 53.8%; p < 0.05). Girls improved their flexibility component (sit-and-reach test), with a higher percentage meeting the healthy zone in 2018 (32.6% vs. 36.9%; p < 0.05); an opposite trend was seen for boys (65.5% vs. 50.1%; p < 0.05). The present investigation provides new and updated PF percentile curves for Portuguese youth, which can be used as a general overview of the current PF state among the Portuguese young population.

Results from Portugal's 2022 report card on physical activity for children and youth.

Background: The purpose of this study is to update results of Portuguese's Report Card on Physical activity (PA) for Children and Adolescents. Methods: The grades were assigned by results derived from the PA and Fitness in Portugal 2021 Portuguese Report Card and corresponds to the third report for the Portuguese children and adolescents. It includes indicators of PA and sedentary behavior (SB) that are common to the GLOBAL matrix 4.0: Overall Physical Activity, Organized Sport and Physical Activity, Active Play, Active Transportation, Sedentary Behaviors, Family and Peers, School, Community and the Environment, Government and Physical Fitness. The search focused on published national evidence/data sources (academia, NGO, governmental) from end 2018 onwards excluding data obtained during the covid-19 pandemic. Results: The grades were assigned as follows: Overall PA (D-), Organized Sport Participation (C-), Active Play (D+), Active Transportation (D-), Sedentary behaviors (C+), Physical Fitness (C), Family and Peers (B), School (A), Community and Environment (B), and Government (B). Conclusion: In line with previous Portuguese Report Cards, a large proportion of Portuguese children and adolescents are not sufficiently active nor fit enough setting urgency for effective strategies. Particular attention should be given to Active play, Active transport and Organized Sports Participation has their grades have decreased. Some actions in selected indicators as Governmental and policy seems promising however results weren't seen yet. Despite the strong support of schools with mandatory curricula in PE no correspondent change is observed in fitness or PA, so more research is needed to find why.

Acyl-Homoserine Lactone from Plant-Associated Pseudomonas sp. Influences Solanum lycopersicum Germination and Root Growth.

It is known that plant and associated bacteria coevolved, but just now the roles of chemical signaling compounds in these intricate relationships have been systematically studied. Many Gram-negative bacteria produce N-acyl-L-homoserine lactones (AHL), chemical signals used in quorum-sensing bacterial communications mechanisms. In recent years, it has been shown that these compounds may also influence the development of plants, acting as allelochemicals, in still not well understood eukaryot-prokaryot interactions. In the present work, a quorum-sensing molecule produced by the tomato associated bacterium Pseudomonas sp. was characterized and its effects on germination and growth of tomato seedlings were accessed. The chemical study of the bacterium extract led to the identification of N-3-oxo-dodecanoyl-L-homoserine lactone (1), using gas chromatography coupled to electron impact mass spectrometry (GC-MS), and ultra-high resolution Qq-time-of-flight mass spectrometry (UHR-QqTOF-MS) equipped with an electrospray ionization source (ESI). The synthetic compound was tested at different concentrations in tomato to evaluate its effects on seed germination and seedlings root growth. Inhibition of tomato seed germination and root growth were observed in the presence of micromolar concentrations of the compound 1. Scanning electron microscopy evidenced morphological alterations on roots in the presence of the compound, with reduction of growth, impaired root hairs development and cracks in the rhizodermis.

2B4 (CD244, SLAMF4) and CS1 (CD319, SLAMF7) in systemic lupus erythematosus and cancer.

Signaling Lymphocyte Activation Molecule (SLAM) family receptors are expressed on different types of hematopoietic cells and play important role in immune regulation in health and disease. 2B4 (CD244, SLAMF4) and CS1 (CD319, CRACC, SLAMF7) were originally identified as NK cell receptors regulating NK cell cytolytic activity. 2B4 is expressed on all NK cells, a subpopulation of T cells, monocytes and basophils. Unlike other activating and inhibitory receptors, 2B4 (CD244) interaction with its ligand CD48 has been shown to mediate both activating and inhibitory functions. Defective signaling via 2B4 due to mutations in signaling adaptor SAP contributes to X-linked lymphoproliferative Disease (XLP). Expression of 2B4 and CS1 are altered in systemic lupus erythematosus (SLE). CS1 is overexpressed in multiple myeloma (MM) and anti-CS1 mab (Elotuzumab/Empliciti) has been approved by FDA as a breakthrough drug for treatment for MM patients. CAR -T cells or CAR- NK cells containing full length CS1 or the signaling domain of 2B4 with TCR-ζ have shown promising results to treat cancer and autoimmune diseases.

Peptides from Mucuna pruriens L., with protection and antioxidant in vitro effect on HeLa cell line.

BACKGROUND: Mucuna pruriens L. is a legume sown in the Mexican southeast with an important protein content. Studies have shown the potential use of by-products derived from Mucuna as a functional food because of the hypoglycemic and antihypertensive activities. Thus, this study aims to assess the antioxidant and protective effect of the peptide fractions derived from M. pruriens L., in vitro on the HeLa cell line. An enzymatic hydrolysis with pepsin-pancreatin was performed on the total protein concentrate, from which five peptide fractions were obtained. RESULTS: All protein derivatives from M. pruriens L., except F5-10 kDa, decreased the hydrogen peroxide production by more than 50%. The highest antioxidant activity was exhibited by F1-3 kDa, which lowered the intracellular reactive oxygen species by 207 ± 4.20%. No significant differences were found in the protective effects of the protein hydrolysate, F5-10 kDa, F3-5 kDa and F1-3 kDa relative to the N-acetylcysteine control group. CONCLUSION: This elucidated the potential action mechanisms of M. pruriens L. protein derivatives for future investigations and their role in the prevention and treatment of oxidative stress. © 2019 Society of Chemical Industry.

Trypanosoma sp. diversity in Amazonian bats (Chiroptera; Mammalia) from Acre State, Brazil.

Bats are ancient hosts of Trypanosoma species and their flying ability, longevity and adaptability to distinct environments indicate that they are efficient dispersers of parasites. Bats from Acre state (Amazon Biome) were collected in four expeditions conducted in an urban forest (Parque Zoobotânico) and one relatively more preserved area (Seringal Cahoeira) in Rio Branco and Xapuri municipalities. Trypanosoma sp. infection was detected by hemoculture and fresh blood examination. Isolated parasite species were identified by the similarity of the obtained DNA sequence from 18S rDNA polymerase chain reaction and reference strains. Overall, 367 bats from 23 genera and 32 species were examined. Chiropterofauna composition was specific to each municipality, although Artibeus sp. and Carollia sp. prevailed throughout. Trypanosoma sp. infection was detected in 85 bats (23·2%). The most widely distributed and prevalent genotypes were (in order) Trypanosoma cruzi TcI, T. cruzi marinkellei, Trypanosoma dionisii, T. cruzi TcIV and Trypanosoma rangeli. At least one still-undescribed Trypanosoma species was also detected in this study. The detection of T. cruzi TcI and TcIV (the ones associated with Chagas disease in Amazon biome) demonstrates the putative importance of these mammal hosts in the epidemiology of the disease in the Acre State.

The influence of Generalized Anxiety Disorder on Executive Functions in children with ADHD.

The present study was aimed at verifying whether the presence of generalized anxiety disorder (GAD) affects executive functions in children with attention-deficit hyperactivity disorder (ADHD). Two groups of children with ADHD were selected for the study according to the presence or absence of GAD. The first group of 28 children with ADHD with GAD (mean age: 9 ± 1.2; males/females: 24/4) was matched for gender, age, IQ, psychiatric comorbidity with a second group of 29 children with ADHD without GAD (mean age: 8.8 ± 0.7; males/females: 26/3). The two groups with ADHD were compared to 28 typically developing children (mean age: 8.3 ± 1.3; males/females: 23/5) on different measures involving processes especially important in inhibitory control such as rule maintenance, stimulus detection, action selection and action execution. Our results indicated that, differently from children with ADHD with GAD, only the group with ADHD without GAD showed a deficit in inhibitory control. Comorbid subgroups should be differentiated, especially, to develop specific and efficient therapeutic interventions in ADHD.

The RNA template channel of the RNA-dependent RNA polymerase as a target for development of antiviral therapy of multiple genera within a virus family.

The genus Enterovirus of the family Picornaviridae contains many important human pathogens (e.g., poliovirus, coxsackievirus, rhinovirus, and enterovirus 71) for which no antiviral drugs are available. The viral RNA-dependent RNA polymerase is an attractive target for antiviral therapy. Nucleoside-based inhibitors have broad-spectrum activity but often exhibit off-target effects. Most non-nucleoside inhibitors (NNIs) target surface cavities, which are structurally more flexible than the nucleotide-binding pocket, and hence have a more narrow spectrum of activity and are more prone to resistance development. Here, we report a novel NNI, GPC-N114 (2,2'-[(4-chloro-1,2-phenylene)bis(oxy)]bis(5-nitro-benzonitrile)) with broad-spectrum activity against enteroviruses and cardioviruses (another genus in the picornavirus family). Surprisingly, coxsackievirus B3 (CVB3) and poliovirus displayed a high genetic barrier to resistance against GPC-N114. By contrast, EMCV, a cardiovirus, rapidly acquired resistance due to mutations in 3Dpol. In vitro polymerase activity assays showed that GPC-N114 i) inhibited the elongation activity of recombinant CVB3 and EMCV 3Dpol, (ii) had reduced activity against EMCV 3Dpol with the resistance mutations, and (iii) was most efficient in inhibiting 3Dpol when added before the RNA template-primer duplex. Elucidation of a crystal structure of the inhibitor bound to CVB3 3Dpol confirmed the RNA-binding channel as the target for GPC-N114. Docking studies of the compound into the crystal structures of the compound-resistant EMCV 3Dpol mutants suggested that the resistant phenotype is due to subtle changes that interfere with the binding of GPC-N114 but not of the RNA template-primer. In conclusion, this study presents the first NNI that targets the RNA template channel of the picornavirus polymerase and identifies a new pocket that can be used for the design of broad-spectrum inhibitors. Moreover, this study provides important new insight into the plasticity of picornavirus polymerases at the template binding site.

Toward antiviral therapy/prophylaxis for rhinovirus-induced exacerbations of chronic obstructive pulmonary disease: challenges, opportunities, and strategies.

Chronic obstructive pulmonary disease (COPD) is a life-threatening lung illness characterized by persistent and progressive airflow limitation. Exacerbations of COPD contribute to the severity of this pathology and accelerate disease progression. To date, pharmacological treatment of both stable COPD patients and patients experiencing exacerbations is mainly symptomatic with bronchodilators and steroids as the mainstay of therapy. Bacteria trigger such exacerbations in a number of cases; hence, antibiotics might be included in the treatment as well. Several respiratory viruses are frequently detected in sputum from patients during COPD exacerbations. These include influenza viruses, respiratory syncytial virus, and, most often, rhinoviruses. In this review, we discuss the potential use of an anti-rhinovirus drug for the treatment and prophylaxis of rhinovirus-induced COPD exacerbations and the path forward toward the development and use of such a drug. Copyright © 2015 John Wiley & Sons, Ltd.

Abdominal obesity in adolescents: Development of age-specific waist circumference cut-offs linked to adult IDF criteria.

OBJECTIVES: The purpose of this study was to develop age- and sex-specific waist circumference (WC) cut-off points, linked to older adolescent and adult criteria for abdominal obesity, to be applied to children in the clinical setting. METHODS: A total of 16,788 adolescents aged 10 to 16 years were assessed for WC. Smoothed age and sex-specific WC curves were obtained using Cole's LMS method. RESULTS: Percentiles that corresponded to the International Diabetes Federation (IDF) recommendations used for older adolescents and adults (16+ years old) were the 97th percentile for boys and the 87th percentile for girls. Using these cutoffs, a total of 368 boys and 1138 girls were categorized as abdominally obese, in contrast to 1654 boys and 987 girls that were identified using the current IDF pediatric criteria (90th percentile). CONCLUSIONS: We provide age- and sex-specific cut-off points that can be used to identify abdominal obesity in adolescents. The present findings provide a tool that can be used in the clinical setting for the early detection and prevention of adult obesity. Population-specific cutoffs may be required for pediatric ages to diagnose children at risk.

Radiographic assessment of humeroulnar congruity in a medium and a large breed of dog.

Elbow joint incongruity is recognized as an important factor in the development, treatment, and prognosis of canine elbow dysplasia. Elbow incongruity has been measured based on radiographic joint space widths, however these values can be affected by the degree of elbow joint flexion. Recent studies have reported radiographic curvature radii as more precise measures of humeroulnar congruity in dogs. The aim of this prospective observational study was to describe radiographic curvature radii measured from flexed and extended elbow radiographs for a sample of dogs representing a medium breed (Portuguese Pointing Dog) and a large breed (Estrela Mountain Dog). The curvature radii from the ulnar trochlear notch and humeral trochlea were measured in 114 mediolateral elbow extended radiographic views (30 Portuguese Pointing Dog and 27 Estrela Mountain Dog), and 84 mediolateral flexed views (22 Portuguese Pointing Dog and 20 Estrela Mountain Dog). The sampled animals' ages ranged from 12 to 84 months (34.6 ± 17.8 months). Good agreement was observed between curvature radii measurements for flexed vs. extended views in both breed groups. Ulnar trochlear notch curvature radii measurements were greater than humeral trochlea curvature radii measurements in both breed groups. Both curvature radii were greater in the large-breed dog group vs. the medium-breed dog group. Both breed groups had ulnar and humeral curves with similar typology. However, the large breed group had greater intermediate differences between the humeroulnar surface curvature radii. Results from this study supported the use of curvature radii as measures of humeroulnar congruity in mediolateral flexed elbow radiographs of medium and large breed dogs.

[Detection and early treatment of subjects at high risk of clinical psychosis: Definitions and recommendations]. / Détection et traitement précoce des sujets à haut risque clinique de psychose : définitions et recommandations.

In children and adolescents, psychotic disorders already represent one of the leading causes of disability-adjusted life years. During the past two decades, early detection of risk for psychosis has been intensively investigated, and in particular, predictive power for early signs of risk has been initiated and translated into clinical practice. In particular, the attenuated and transient positive symptoms of the ultra-high risk criteria, and the basic symptom criterion "cognitive disturbances", open promising routes to an indicated prevention and have recently been considered by the European Psychiatric Association (EPA) as diagnostic criteria of a psychosis-risk syndrome. The EPA recently provided evidence-based recommendations on the early detection of clinical high risk (CHR) for psychosis in patients with mental distress. In 2015, experts in the field of early detection conducted a meta-analysis reporting on studies examining conversion rates to psychosis in non-overlapping samples meeting at least one of the main CHR criteria: ultra-high risk (UHR) and/or basic symptoms criteria, examining the effects of potential moderators (different UHR criteria definitions, single UHR criteria and age) on conversion rates. In the 42 identified samples, comprising more than 4000 CHR patients who had been mainly identified by means of UHR criteria and/or the basic symptom criterion 'cognitive disturbances' (COGDIS), conversion rates showed considerable heterogeneity. While UHR and COGDIS criteria were related to comparable conversion rates until a 2-year follow-up, rates for COGDIS were significantly higher for follow-up periods beyond 2 years. Differences in onset and frequency requirements of symptomatic UHR criteria, or in their different consideration of functional decline, substance use and co-morbidity, did not seem to have an impact on conversion rates. The 'genetic risk and functional decline' UHR criterion was rarely met and only showed an insignificant pooled sample effect. However, age significantly affected UHR conversion rates with lower rates in children and adolescents. Although more research into potential sources of heterogeneity in conversion rates is needed to facilitate improvement of CHR criteria, six evidence-based recommendations for the early detection of psychosis were developed as a basis for the EPA guidance on early intervention in CHR states. The EPA guidance on early intervention aimed to provide evidence-based recommendations on early intervention in CHR states of psychosis, assessed according to the EPA guidance on early detection. The recommendations were also made by experts in the field of early intervention in psychoses and derived from a meta-analysis of current empirical evidence on the efficacy of psychological and pharmacological interventions in CHR samples. Eligible studies had to investigate conversion rate and/or functioning as a treatment outcome in CHR patients defined by the ultra-high risk and/or basic symptom criteria. In addition to analyses of treatment effects on conversion rate and functional outcome, age and type of intervention were examined as potential moderators. Based on data from 15 studies (n=1394), early intervention generally produced significantly reduced conversion rates at 6- to 48-month follow-up compared to control conditions. However, early intervention failed to achieve significantly greater functional improvements because both early intervention and control conditions produced similar positive effects. With regard to the type of intervention, both psychological and pharmacological interventions produced significant effects on conversion rates but not on functional outcome relative to the control conditions. Early intervention in youth samples was generally less effective than in predominantly adult samples. Seven evidence-based recommendations for early intervention in CHR samples have been formulated, although more studies are needed to investigate the specificity of treatment effects and potential age effects in order to tailor interventions to the individual treatment needs and risk status. Overall, age-related specificities and developmental transitions in the early detection and intervention in psychoses should be better accounted for in future research.

Interactome analysis of the human respiratory syncytial virus RNA polymerase complex identifies protein chaperones as important cofactors that promote L-protein stability and RNA synthesis.

UNLABELLED: The human respiratory syncytial virus (HRSV) core viral RNA polymerase comprises the large polymerase protein (L) and its cofactor, the phosphoprotein (P), which associate with the viral ribonucleoprotein complex to replicate the genome and, together with the M2-1 protein, transcribe viral mRNAs. While cellular proteins have long been proposed to be involved in the synthesis of HRSV RNA by associating with the polymerase complex, their characterization has been hindered by the difficulty of purifying the viral polymerase from mammalian cell culture. In this study, enhanced green fluorescent protein (EGFP)-tagged L- and P-protein expression was coupled with high-affinity anti-GFP antibody-based immunoprecipitation and quantitative proteomics to identify cellular proteins that interacted with either the L- or the P-proteins when expressed as part of a biologically active viral RNP. Several core groups of cellular proteins were identified that interacted with each viral protein including, in both cases, protein chaperones. Ablation of chaperone activity by using small-molecule inhibitors confirmed previously reported studies which suggested that this class of proteins acted as positive viral factors. Inhibition of HSP90 chaperone function in the current study showed that HSP90 is critical for L-protein function and stability, whether in the presence or absence of the P-protein. Inhibition studies suggested that HSP70 also disrupts virus biology and might help the polymerase remodel the nucleocapsid to allow RNA synthesis to occur efficiently. This indicated a proviral role for protein chaperones in HRSV replication and demonstrates that the function of cellular proteins can be targeted as potential therapeutics to disrupt virus replication. IMPORTANCE: Human respiratory syncytial virus (HRSV) represents a major health care and economic burden, being the main cause of severe respiratory infections in infants worldwide. No vaccine or effective therapy is available. This study focused on identifying those cellular proteins that potentially interact specifically with the viral proteins that are central to virus replication and transcription, with a view to providing potential targets for the development of a specific, transient therapeutic which disrupts virus biology but prevents the emergence of resistance, while maintaining cell viability. In particular, protein chaperones (heat shock proteins 70 and 90), which aid protein folding and function, were identified. The mechanism by which these chaperones contribute to virus biology was tested, and this study demonstrates to the field that cellular protein chaperones may be required for maintaining the correct folding and therefore functionality of specific proteins within the virus replication complex.

Acyl-homoserine Lactone from Saccharum × officinarum with Stereochemistry-Dependent Growth Regulatory Activity.

Acyl-homoserine lactones (AHLs) are a class of compounds produced by Gram-negative bacteria that are used in a process of chemical communication called quorum sensing. Much is known about how bacteria use these chemical compounds to control the expression of important factors; however, there have been few reports about the presence and effects of AHLs in plants. In this study, the phytochemical study of leaves and culms of sugar cane (Saccharum × officinarum) led to the identification of N-(3-oxo-octanoyl)homoserine lactone. Since the absolute configuration of the natural product could not be determined, both R and S enantiomers of N-(3-oxo-octanoyl)homoserine lactone were synthesized and tested in sugar cane culms. The enantiomers caused changes in the mass and length of buds and roots when used at micromolar concentrations. Using the sugar cane RB96-6928 variety, the S enantiomer increased sprouting of roots more effectively than the R enantiomer. Furthermore, scanning electron microscopy showed that both the R and S enantiomers led to more stretched root cells compared with the control.

Phenolic compounds and anticancer activity of commercial sugarcane cultivated in Brazil.

The cultivation of sugarcane hybrids (X Saccharum officinarum L.) is an important revenue source for the Brazilian economy. Herein it is reported the evaluation of the cytotoxic activity of mid-polarity sugarcane extracts against human cancer cell lines, as well as the isolation of steroids sitosterol, stigmasterol and campesterol, phenolic acids p-hydroxybenzoic, p-hydroxycinnamic, vanillic and ferulic acid, terpenoids α-tocopherol and ß-carotene and a novel substance in sugarcane, the flavonoid aglycone tricin (5,7,4-trihydroxy-3,5-dimethoxyflavone). The presence of large amounts of phenolic acids and the flavonoid tricin may explain the cytostatic activity observed for the mid-polarity crude extract and filtrates.

Acute toxicity, antiedematogenic activity, and chemical constituents of Palicourea rigida Kunth.

The phytochemical study of the leaves, roots, and flowers of Palicourea rigida led to the isolation of the triterpenes betulinic acid (1) and lupeol (2), the diterpene phytol (3), and the iridoid glycosides sweroside (4) and secoxyloganin (5). These compounds were identified using NMR 1H and 13C and comparing the spectra with published data. We studied the antiedematogenic activity of crude extracts from the organs, and of different fractions, in mice and found that the n-hexane fraction of the leaf extract significantly inhibited the ear edema resulting from croton oil administration. The crude extract from leaves was not acutely toxic to the mice.

Rotifer dynamics in three shallow lakes from the Salado river watershed (Argentina): the potential modulating role of incident solar radiation.

In turbid Pampean lakes, incident solar radiation is a major driver of plankton seasonal dynamics. Higher light availability in summer translates into higher primary production, and therefore more food for zooplankton grazers. However, experimental evidence suggests that food produced under the high irradiance conditions prevailing in summer are less suitable to sustain rotifer population growth than that produced under the lower irradiance conditions typical of winter. Here, we analysed time series datasets corresponding to three shallow lakes from the Salado river watershed. This analysis provided evidence for similar seasonal patterns of rotifer relative abundance over a large geographic area. In addition, we performed life table experiments to test the hypothesis that natural seston produced in winter could sustain higher population growth rates than seston produced in summer. We suggest that the natural seasonal changes in temperature and food generate successive time windows, which may be capitalized by the different grazer species, resulting in predictable phenology of grazer populations.