We present a catalog of mean proper motions and membership probabilities of individual stars for optically visible open clusters, which have been determined using data from the UCAC4 catalog in a ...homogeneous way. The mean proper motion of the cluster and the membership probabilities of the stars in the region of each cluster were determined by applying the statistical method in a modified fashion. In this study, we applied a global optimization procedure to fit the observed distribution of proper motions with two overlapping normal bivariate frequency functions, which also take the individual proper motion errors into account. For 724 clusters, this is the first determination of proper motion, and for the whole sample, we present results with a much larger number of identified astrometric member stars. Furthermore, it was possible to estimate the mean radial velocity of 364 clusters (102 unpublished so far) with the stellar membership using published radial velocity catalogs. These results provide an increase of 30% and 19% in the sample of open clusters with a determined mean absolute proper motion and mean radial velocity, respectively.
Abstract Phytochemical studies of Cespedesia spathulata (Ochnaceae) leaves using 1H, 13C NMR, and GC-MS have led to the isolation of some metabolites identified for the first time in these species ...such as cathechin, epicatechin, vitexin, orientin, 6’’-O-acetyl-vitexin, sitosterol, stigmasterol, phytol, 4,5-dihydrovomifoliol and a mixture of aliphatic methyl esters, together with ochnaflavone, which was previously isolated from this plant. The modulating activity of some fractions and compounds from Cespedesia spathulata towards tyrosinase enzyme was assayed by spectroscopic and theoretical means/experiments. The dichloromethane fraction (133 μg mL-1) and ochnaflavone (333 μM) inhibited tyrosinase activity by 20 % and 2.0 %, respectively, whereas the ethyl acetate fraction (666 μg mL-1) and ±catechins (catechin and epicatechin - 800 μM) activated it by 104 % and 384 %, respectively. Quantum chemical calculations suggested that catechin and epicatechin are better activators than L-DOPA by interacting with Cu (II) ions. Molecular docking results suggested that hydrogen bonding and hydrophobic interactions are the main binding forces between each tyrosinase activator and the amino acid residues inside the active protein binding pocket.
Cenostigma macrophyllum Tul. var. acuminata Teles Freire (Leguminosae-Caesalpinioideae), popularly known in Brazil as “caneleiro”, is widely used in folk medicine against gastrointestinal diseases. ...In previous studies, the ethanol extract of leaves from Cenostigma macrophyllum Tul. var. acuminata Teles Freire had shown antinociceptive, anti-inflammatory, antibacterial, antioxidant and antiulcerogenic activities.
The aim of this study was to assess the gastroprotective effect of the hydroalcoholic fraction of leaves of Cenostigma macrophyllum Tul. var. acuminata Teles Freire (Cm-FHA), as well as to elucidate the possible underlying mechanisms of action.
Mice were used for the evaluation of the acute toxicity, and mice and rats to study the gastroprotective activity. The potential gastroprotective of Cm-FHA was assessed on different gastric ulcer models in rodents, such as absolute ethanol, HCl/ethanol, ischemia-reperfusion, cold restraint stress and indomethacin. The participation of prostaglandins, NO-synthase pathway and ATP-sensitive potassium channels (KATP) in gastroprotective activity of Cm-FHA were evaluated after treatment with a cyclooxygenase inhibitor (indomethacin), a NO-synthase inhibitor (L-NAME) and a KATP channel blocker (glibenclamide 5mg/kg), respectively. Likewise, the catalase activity was determinated in order to assess the possible participation of antioxidant mechanisms.
No signs of acute toxicity was observed after oral acute administration of Cm-FHA, considering the analyzed parameters. Likewise, Cm-FHA promoted a protective effect against gastric ulcers induced by absolute ethanol (lesion inhibition by 40% at both 100 and 200mg/kg), HCl/ethanol (lesion inhibition by 50 or 48% at 100 or 200mg/kg, respectively), ischemia-reperfusion (lesion inhibition by 49 or 90% at 100 or 200mg/kg, respectively) and cold restraint stress (lesion inhibition by 63 or 76% at 100 or 200mg/kg, respectively), as well as a increase of catalase activity was observed. Otherwise, Cm-FHA was not able to protect gastric mucosa against indomethacin-induced lesions. Nitric oxide release, the of KATP channels opening and antioxidant activity are the possibly involved in the Cm-FHA-induced gastroprotective activity.
This study corroborates the folk medicine use of Cenostigma macrophyllum for treatment of gastric ulcers, as well as reinforces this species as a valuable source of promising natural drugs with gastroprotective activity.
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Recent studies have shown that the addition of non-viable microbial biomass or their components (postbiotics) to fish feed can modulate the gut microbiome and positively influence fish health in ...aquaculture systems. However, no information was hitherto available on the use of non-viable microbial biomass to manipulate aquaculture bacterioplankton communities. To fill this gap, here we used an in vitro model to assess the effects of heat-killed biomasses of an antagonistic strain Pseudoalteromonas rubra SubTr2 and a non-antagonist strain Escherichia coli DH5α on bacterioplankton communities of a recirculating aquaculture system (RAS). Our results showed that these biomasses can have generalist and species-specific effects on aquaculture bacterioplankton structure and function. In addition, they enriched the abundance of bacterial predators, reduced bacterial load and potentially influenced nutrient cycling and pathogen development in aquaculture water. Despite its preliminary nature, for the first time, this study showed that heat-killed microbial biomass has potential application as an in situ modulator of bacterioplankton in aquaculture systems.
Alzheimer's disease is the commonest cause of dementia in the elderly, but its pathological determinants are still debated. Amyloid-β plaques and neurofibrillary tangles have been implicated either ...directly as disruptors of neural function, or indirectly by precipitating neuronal death and thus causing a reduction in neuronal number. Alternatively, the initial cognitive decline has been attributed to subtle intracellular events caused by amyloid-β oligomers, resulting in dementia after massive synaptic dysfunction followed by neuronal degeneration and death. To investigate whether Alzheimer's disease is associated with changes in the absolute cell numbers of ageing brains, we used the isotropic fractionator, a novel technique designed to determine the absolute cellular composition of brain regions. We investigated whether plaques and tangles are associated with neuronal loss, or whether it is dementia that relates to changes of absolute cell composition, by comparing cell numbers in brains of patients severely demented with those of asymptomatic individuals-both groups histopathologically diagnosed as Alzheimer's-and normal subjects with no pathological signs of the disease. We found a great reduction of neuronal numbers in the hippocampus and cerebral cortex of demented patients with Alzheimer's disease, but not in asymptomatic subjects with Alzheimer's disease. We concluded that neuronal loss is associated with dementia and not the presence of plaques and tangles, which may explain why subjects with histopathological features of Alzheimer's disease can be asymptomatic; and exclude amyloid-β deposits as causes for the reduction of neuronal numbers in the brain. We found an increase of non-neuronal cell numbers in the cerebral cortex and subcortical white matter of demented patients with Alzheimer's disease when compared with asymptomatic subjects with Alzheimer's disease and control subjects, suggesting a reactive glial cell response in the former that may be related to the symptoms they present.
Epidemiologic studies have highlighted the association of environmental factors with the development and progression of autoimmune and chronic inflammatory diseases. Among the environmental factors, ...smoking has been associated with increased susceptibility and poor prognosis in rheumatoid arthritis (RA). However, the immune and molecular mechanism of smoking-induced arthritis aggravation remains unclear. The transcription factor aryl hydrocarbon receptor (AHR) regulates the generation of Th17 cells, CD4 T cells linked the development of autoimmune diseases. AHR is activated by organic compounds including polycyclic aromatic hydrocarbons (PAHs), which are environmental pollutants that are also present in cigarette smoke. In this study, we investigated the role of AHR activation in the aggravation of experiment arthritis induced by exposure to cigarette smoke.
Mice were exposed to cigarette smoke during the developmental phase of antigen-induced arthritis and collagen-induced arthritis to evaluate the effects of smoking on disease development. Aggravation of articular inflammation was assessed by measuring neutrophil migration to the joints, increase in articular hyperalgesia and changes in the frequencies of Th17 cells. In vitro studies were performed to evaluate the direct effects of cigarette smoke and PAH on Th17 differentiation. We also used mice genetically deficient for AHR (Ahr KO) and IL-17Ra (Il17ra KO) to determine the in vivo mechanism of smoking-induced arthritis aggravation.
We found that smoking induces arthritis aggravation and increase in the frequencies of Th17 cells. The absence of IL-17 signaling (Il17ra KO) conferred protection to smoking-induced arthritis aggravation. Moreover, in vitro experiments showed that cigarette smoke can directly increase Th17 differentiation of T cells by inducing AHR activation. Indeed, Ahr KO mice were protected from cigarette smoke-induced arthritis aggravation and did not display increase in TH17 frequencies, suggesting that AHR activation is an important mechanism for cigarette smoke effects on arthritis. Finally, we demonstrate that PAHs are also able to induce arthritis aggravation.
Our data demonstrate that the disease-exacerbating effects of cigarette smoking are AHR dependent and environmental pollutants with AHR agonist activity can induce arthritis aggravation by directly enhancing Th17 cell development.
Bacteriophages are the most abundant and diverse entities in the biosphere, and this diversity is driven by constant predator-prey evolutionary dynamics and horizontal gene transfer. Phage genome ...sequences are under-sampled and therefore present an untapped and uncharacterized source of genetic diversity, typically characterized by highly mosaic genomes and no universal genes. To better understand the diversity and relationships among phages infecting human pathogens, we have analysed the complete genome sequences of 205 phages of Staphylococcus sp.
These are predicted to encode 20,579 proteins, which can be sorted into 2139 phamilies (phams) of related sequences; 745 of these are orphams and possess only a single gene. Based on shared gene content, these phages were grouped into four clusters (A, B, C and D), 27 subclusters (A1-A2, B1-B17, C1-C6 and D1-D2) and one singleton. However, the genomes have mosaic architectures and individual genes with common ancestors are positioned in distinct genomic contexts in different clusters. The staphylococcal Cluster B siphoviridae are predicted to be temperate, and the integration cassettes are often closely-linked to genes implicated in bacterial virulence determinants. There are four unusual endolysin organization strategies found in Staphylococcus phage genomes, with endolysins predicted to be encoded as single genes, two genes spliced, two genes adjacent and as a single gene with inter-lytic-domain secondary translational start site. Comparison of the endolysins reveals multi-domain modularity, with conservation of the SH3 cell wall binding domain.
This study provides a high-resolution view of staphylococcal viral genetic diversity, and insights into their gene flux patterns within and across different phage groups (cluster and subclusters) providing insights into their evolution.
The TIGIT+FOXP3+Treg subset (TIGIT+Tregs) exerts robust suppressive activity on cellular immunity and predisposes septic individuals to opportunistic infection. We hypothesized that TIGIT+Tregs could ...play an important role in intensifying the COVID-19 severity and hampering the defense against nosocomial infections during hospitalization. Herein we aimed to verify the association between the levels of the TIGIT+Tregs with the mechanical ventilation requirement, fatal outcome, and bacteremia during hospitalization. TIGIT+Tregs were immunophenotyped by flow cytometry from the peripheral blood of 72 unvaccinated hospitalized COVID-19 patients at admission from May 29th to August 6th, 2020. The patients were stratified during hospitalization according to their mechanical ventilation requirement and fatal outcome. COVID-19 resulted in a high prevalence of the TIGIT+Tregs at admission, which progressively increased in patients with mechanical ventilation needs and fatal outcomes. The prevalence of TIGIT+Tregs positively correlated with poor pulmonary function and higher plasma levels of LDH, HMGB1, FGL2, and TNF. The non-survivors presented higher plasma levels of IL-33, HMGB1, FGL2, IL-10, IL-6, and 5.54 times more bacteremia than survivors. Conclusions: The expansion of the TIGIT+Tregs in COVID-19 patients was associated with inflammation, lung dysfunction, bacteremia, and fatal outcome.
ABSTRACT
In this paper we present a thorough discussion about the photometric redshift (photo-z) performance of the Southern Photometric Local Universe Survey (S-PLUS). This survey combines a seven ...narrow +5 broad passband filter system, with a typical photometric-depth of r ∼ 21 AB. For this exercise, we utilize the Data Release 1 (DR1), corresponding to 336 deg2 from the Stripe-82 region. We rely on the BPZ2 code to compute our estimates, using a new library of SED models, which includes additional templates for quiescent galaxies. When compared to a spectroscopic redshift control sample of ∼100 k galaxies, we find a precision of σz <0.8 per cent, <2.0 per cent, or <3.0 per cent for galaxies with magnitudes r < 17, <19, and <21, respectively. A precision of 0.6 per cent is attained for galaxies with the highest Odds values. These estimates have a negligible bias and a fraction of catastrophic outliers inferior to 1 per cent. We identify a redshift window (i.e. 0.26 < z < 0.32) where our estimates double their precision, due to the simultaneous detection of two emission lines in two distinct narrow bands; representing a window opportunity to conduct statistical studies such as luminosity functions. We forecast a total of ∼2 M, ∼16 M and ∼32 M galaxies in the S-PLUS survey with a photo-z precision of σz <1.0 per cent, <2.0 per cent, and <2.5 per cent after observing 8000 deg2. We also derive redshift probability density functions, proving their reliability encoding redshift uncertainties and their potential recovering the n(z) of galaxies at z < 0.4, with an unprecedented precision for a photometric survey in the Southern hemisphere.
Due to the rise of multidrug-resistant infections in humans, phage therapy is gaining renewed attention in Western medicine. Despite the increasing number of publications focussed on the isolation, ...characterization and in vitro performance of different phages, there is still a lack of concise pre-clinical information to guide the application of phage therapy in clinical practice. Nevertheless, over the last decade, efforts have been made to conduct more detailed studies of the in vivo efficacy of phages. Here, we review the most relevant in vivo studies performed in the last decade covering phage efficacy in both preclinical and clinical trials. We compare different routes of administration, dosage effect and different animal models of distinct types of infections. Moreover, insights into case studies and results from clinical trials are presented. Challenges and limitations of phage use as evidenced by the current state of research are also discussed in order to improve both the trustworthiness and success of the implementation of phage therapy.
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