Bothrops atrox mice experimental envenoming treatment using light-emitting diode (led) as an adjunct therapy to conventional serum therapy.

The use of anti-venom is one of the main control measures for snakebite envenoming when applied immediately after the snakebite. Systemic effects of the envenoming are usually reversed; however, neutralization of local effects is hardly achieved. The need for adjuvant therapies associated with serum therapy can improve the treatment for local effects of envenoming, with greater effectiveness in preventing or delaying the progression of damage, reducing the clinical signs and symptoms of victims of snakebites. The purpose of the study was to evaluate the photobiomodulation therapy using LED and/or dexamethasone associated with conventional serum therapy for the treatment of local damage caused by Bothrops atrox envenomation in a murine model. For this, experimental envenoming was carried out in the gastrocnemius muscle of male Swiss mice weighing 18 to 22 g divided into 8 groups of animals, distributed in groups non-treat, treated with anti-bothropic serum, dexamethasone, and LED, or the associated treatments, by intramuscular inoculation of 50 µg of venom or sterile PBS (control). After 30 min, the proposed treatments were administered alone or in combination. After 3 h, blood and muscle samples were collected for myotoxicity, cytotoxicity, histological analysis, and IL-1ß assays. The evaluation of the treatment alone showed that serum therapy is not effective for the treatment of local damage and photobiomodulation demonstrated to be an effective therapy to reduce leukocyte infiltration, hemorrhage, and myotoxicity in experimental envenoming; dexamethasone proved to be a good resource for the treatment of the inflammatory process reducing the leukocyte infiltration. The association of serum therapy, LED, and dexamethasone was the best treatment to reduce the local effects caused by Bothrops atrox venom. All in all, the association of photobiomodulation therapy using LED with conventional serum therapy and the anti-inflammatory drug is the best treatment for reducing the undesirable local effects caused by snakebite accidents involving B. atrox species.

Lipids: biomarkers of healthy aging.

Life expectancy, and longevity have been increasing in recent years. However, this is, in most cases, accompanied by age-related diseases. Thus, it became essential to better understand the mechanisms inherent to aging, and to establish biomarkers that characterize this physiological process. Among all biomolecules, lipids appear to be a good target for the study of these biomarkers. In fact, some lipids have already been associated with age-related diseases. With the development of analytical techniques such as Mass Spectrometry, and Nuclear Magnetic Resonance, Lipidomics has been increasingly used to study pathological, and physiological states of an organism. Thus, the study of serum, and plasma lipidome in centenarians, and elderly individuals without age-related diseases can be a useful tool for the identification of aging biomarkers, and to understand physiological aging, and longevity. This review focus on the importance of lipids as biomarkers of aging, and summarize the changes in the lipidome that have been associated with aging, and longevity.

The incidence of bent dorsal fins in free-ranging cetaceans.

Laterally bent dorsal fins are rarely observed in free-ranging populations of cetaceans, contrary to captivity, where most killer whale Orcinus orca adult males have laterally collapsed fins. This topic has been poorly explored, and data/information on its occurrence and possible causes are limited. The present study: (i) undertakes a review of the available information on bent dorsal fins in free-ranging cetaceans, and updates it with new records, (ii) reports on the proportion of bent fins in different study populations, and (iii) discusses possible causes. An empirical approach based on bibliographic research and compilation of 52 new records collected worldwide resulted in a total of 17 species of cetaceans displaying bent dorsal fins. The species with the highest number of records (64%) and from most locations was O. orca. On average, individuals with bent dorsal fins represent < 1% of their populations, with the exception of false killer whales Pseudorca crassidens and O. orca. While line injuries associated with fisheries interactions may be the main cause for P. crassidens, and the vulnerability to health issues caused by the evolutionary enlargement of the fin may be the cause for O. orca adult males, factors contributing to this abnormality for other species are still unclear. The occurrence of bent dorsals could be influenced by a set of variables rather than by a single factor but, irrespective of the cause, it is suggested that it does not directly affect the animals' survivorship. While still rare in nature, this incident is more common (at least 101 known cases) and widespread (geographically and in species diversity) than hypothesized, and is not confined only to animals in captive environments. Investigation into the occurrence of bent fins may be an interesting avenue of research.

Genetic markers for detection of Escherichia coli K-12 harboring ampicillin-resistance plasmid from an industrial wastewater treatment effluent pond.

Biotechnology industries that use recombinant DNA technology are potential sources for release of genetically modified organisms to the environment. Antibiotic-resistance marker genes are commonly used for recombinant bacteria selection. One example is the marker gene coding for ß-lactamase (bla) in plasmids found in Escherichia coli K-12. The aim of this study was to provide an approach to develop a molecular method for genetic marker detection in E. coli K-12 harboring bla genes from an industrial wastewater treatment effluent pond (IWTEP). For the detection of bla and Achromobacter lyticus protease I (api) genes in samples from IWTEP, we employed multiplex polymerase chain reaction (PCR) using E. coli K-12 genetic marker detection primers, previously described in the literature, and primers designed in our laboratory. The microbiological screening method resulted in 22 bacterial colony-forming units isolated from three different IWTEP harvesting points. The multiplex PCR amplicons showed that five isolates were positive for the bla gene marker and negative for the E. coli K-12 and api genes. The 16S rRNA regions of positive microorganisms carrying the bla gene were genotyped by the MicroSeq®500 system. The bacteria found were Escherichia spp (3/5), Chromobacterium spp (1/5), and Aeromonas spp (1/5). None of the 22 isolated microorganisms presented the molecular pattern of E. coli K-12 harboring the bla gene. The presence of microorganisms positive for the bla gene and negative for E. coli K-12 harboring bla genes at IWTEP suggests that the ampicillin resistance found in the isolated bacteria could be from microorganisms other than the E. coli K-12 strain harboring plasmid.

Analysis of the stability of InGaN/GaN multiquantum wells against ion beam intermixing.

Ion-induced damage and intermixing was evaluated in InGaN/GaN multi-quantum wells (MQWs) using 35 keV N(+) implantation at room temperature. In situ ion channeling measurements show that damage builds up with a similar trend for In and Ga atoms, with a high threshold for amorphization. The extended defects induced during the implantation, basal and prismatic stacking faults, are uniformly distributed across the quantum well structure. Despite the extremely high fluences used (up to 4 × 10(16) cm(-2)), the InGaN MQWs exhibit a high stability against ion beam mixing.

Do mites evolving in alternating host plants adapt to host switch?

A fluctuating environment may be perceived as a composition of different environments, or as an environment per se, in which it is the fluctuation itself that poses a selection pressure. If so, then organisms may adapt to this alternation. We tested this using experimental populations of spider mites that have been evolving for 45 generations in a homogeneous environment (pepper or tomato plants), or in a heterogeneous environment composed of an alternation of these two plants approximately at each generation. The performance (daily oviposition rate and juvenile survival) of individuals from these populations was tested in each of the homogeneous environments, and in two alternating environments, one every 3 days and the other between generations. To discriminate between potential genetic interactions between alleles conferring adaptation to each host plant and environmental effects of evolving in a fluctuating environment, we compared the performance of all lines with that of a cross between tomato and pepper lines. As a control, two lines within each selection regime were also crossed. We found that crosses between alternating lines and between pepper and tomato lines performed worse than crosses between lines evolving in homogeneous environments when tested in that environment. In contrast, alternating lines performed either better or similarly to lines evolving in homogeneous environments when tested in a fluctuating environment. Our results suggest that fluctuating environments are more than the juxtaposition of two environments. Hence, tests for adaptation of organisms evolving in such environments should be carried out in fluctuating conditions.

Effect of a flat band on a multiband two-dimensional Lieb lattice with intra- and interband interactions.

In this study, we explore the effect of a single flat band in the electronic properties of a ferromagnetic two-dimensional Lieb lattice using the multiband Hubbard model with polarized carriers, spin-up and spin-down. We employ the self-consistent dynamical mean field theory and a Green functions cumulant expansion around the atomic limit to obtain the correlated densities of states while varying the intra- and interband interactions. Our findings demonstrate a renormalization of the correlated density of states in both the spin-up and spin-down carriers as we varied the intra- and interband interactions. We conclude that the presence of a flat band enables the system to maintain a metal state with itinerant ferromagnetism in the spin-up carrier.

Enhancement of the magnetocaloric effect in geometrically frustrated cluster spin glass systems.

In this work, we theoretically demonstrate that a strong enhancement of the magnetocaloric effect is achieved in geometrically frustrated cluster spin-glass systems just above the freezing temperature. We consider a network of clusters interacting randomly which have triangular structure composed of Ising spins interacting antiferromagnetically. The intercluster disorder problem is treated using a cluster spin glass mean-field theory, which allows exact solution of the disordered problem. The intracluster part can be solved using exact enumeration. The coupling between the inter and intracluster problem incorporates the interplay between effects coming from geometric frustration and disorder. As a result, it is shown that there is the onset of cluster spin glass phase even with very weak disorder. Remarkably, it is exactly within a range of very weak disorder and small magnetic field that is observed the strongest isothermal release of entropy.

Case report of isochromosome 17q in acute myeloid leukemia with myelodysplasia-related changes after treatment with a hypomethylating agent.

Isochromosome 17q is a relatively common karyotypic abnormality in medulloblastoma, gastric, bladder, and breast cancers. In myeloid disorders, it is observed during disease progression and evolution to acute myeloid leukemia in Philadelphia-positive chronic myeloid leukemia. It has been reported in rare cases of myelodysplastic syndrome, with an incidence of 0.4-1.57%. Two new agents have been approved for treatment of myelodysplastic syndrome/chronic myelomonocytic leukemia. These are the hypomethylating agents, 5-azacytidine and decitabine, recommended by consensus guidelines for high-risk myelodysplastic syndrome patients not eligible for hematopoietic stem cell transplantation. We present a case of chronic myelomonocytic leukemia with normal cytogenetics at diagnosis treated with decitabine (with good response); however, the patient evolved to acute myeloid leukemia with i(17q) shortly after suspending treatment. To the best of our knowledge, this is the first report of acute myeloid leukemia with myelodysplasia-related changes with i(17q) after the use of a hypomethylating agent.

Age, Blasts, Performance Status and Lenalidomide Therapy Influence the Outcome of Myelodysplastic Syndrome With Isolated Del(5q): A Study of 58 South American Patients.

BACKGROUND: Myelodysplastic Syndrome (MDS) with isolated deletion 5q is associated with a low risk to leukemic evolution and long overall survival (OS); it comprises 3%-4.5% of MDS cases in Latin America classified according to the World Health Organization 2008. This study aims to describe clinical, laboratory and the outcome of patients according to the newest World Health Organization 2016 proposal. METHODS: We retrospectively reviewed patients from four Brazilian (BR) and four Argentinean (AR) centers diagnosed between 1999 and 2019. RESULTS: The 58 patients (16-AR and 42-BR) presented a median age of 67 (IQR 61-75) years old, women predominance (70.7%) and transfusion dependency (62.5%) at diagnosis. Median hemoglobin level was 8.1g/dL, 27.5% and 44.4% presented thrombocytosis and neutropenia, respectively. Bone marrow (BM) was predominantly hypercellular (43.1%) with 66% showing dysplasia >1 lineage and 37.9% with >2% of blasts. Deletion 5q was mostly isolated (79.3%) and a variety of abnormalities were observed in remaining cases. Most patients were treated with erythropoietin-stimulating agents (ESA), 18 with lenalidomide and 15 with thalidomide. Median follow-up was 7.6 years, with a median OS of 3.5 years and an 8-years leukemic evolution rate of 18.4%. Multivariate analysis showed that age >75 years (HR 2.19), ECOG ≥2 (HR 5.76), BM blasts >2% (HR 2.92) and lenalidomide treatment (HR 0.25) independently influenced the OS. CONCLUSION: Older age, worse performance status and higher percentage of blasts, that can be easily assessed, were associated to a worse prognosis. Also, our results corroborate the protective influence of lenalidomide in terms of OS in this South American series.

Environmental effects on the detection of adaptation.

Detecting adaptation involves comparing the performance of populations evolving in different environments. This detection may be confounded by effects due to the environment experienced by organisms prior to the test. We tested whether such confounding effects occur, using spider-mite selection lines on two novel hosts and one ancestral host, after 15 generations of selection. Mites were either sampled directly from the selection lines or subjected to a common juvenile or to a common maternal environment, mimicking the most frequent environmental manipulations. These environments strongly affected all life-history traits. Moreover, the detection of adaptation and correlated responses on the ancestral host was inconsistent among environments in almost 20% of the cases. Indeed, we did not detect responses unambiguously for any life-history trait. This inconsistency was due to differential environmental effects on lines from different selection regimes. Therefore, the detection of adaptation requires a careful control of these environmental effects.

Geometrical frustration and cluster spin glass with random graphs.

We develop a based on a sparse random graph to account for the interplay between geometric frustration and disorder in cluster magnetism. Our theory allows introduction of the cluster network connectivity as a controllable parameter. Two types of inner cluster geometry are considered: triangular and tetrahedral. The theory was developed for general, nonuniform intracluster interactions, but in the present paper the results presented correspond to uniform, antiferromagnetic (AF) intraclusters interaction J_{0}/J. The clusters are represented by nodes on a finite connectivity random graph, and the intercluster interactions are randomly Gaussian distributed. The graph realizations are treated in replica theory using the formalism of order parameter functions, which allows one to calculate the distribution of local fields and, as a consequence, the relevant observable. In the case of triangular cluster geometry, there is the onset of a classical spin liquid state at a temperature T^{*}/J and then, a cluster spin glass (CSG) phase at a temperature T_{/}J. The CSG ground state is robust even for very weak disorder or large negative J_{0}/J. These results does not depend on the network connectivity. Nevertheless, variations in the connectivity strongly affect the level of frustration f_{p}=-Θ_{CW}/T_{f} for large J_{0}/J. In contrast, for the nonfrustrated tetrahedral cluster geometry, the CSG ground state is suppressed for weak disorder or large negative J_{0}/J. The CSG boundary phase presents a reentrance which is dependent on the network connectivity.

Ising spin glass in a random network with a Gaussian random field.

We investigate thermodynamic phase transitions of the joint presence of spin glass (SG) and random field (RF) using a random graph model that allows us to deal with the quenched disorder. Therefore, the connectivity becomes a controllable parameter in our theory, allowing us to answer what the differences are between this description and the mean-field theory i.e., the fully connected theory. We have considered the random network random field Ising model where the spin exchange interaction as well as the RF are random variables following a Gaussian distribution. The results were found within the replica symmetric (RS) approximation, whose stability is obtained using the two-replica method. This also puts our work in the context of a broader discussion, which is the RS stability as a function of the connectivity. In particular, our results show that for small connectivity there is a region at zero temperature where the RS solution remains stable above a given value of the magnetic field no matter the strength of RF. Consequently, our results show important differences with the crossover between the RF and SG regimes predicted by the fully connected theory.

Multicritical points in a model for 5f-electron systems under pressure and magnetic field.

We investigate the evolution of multicritical points under pressure and magnetic field in a model described by two 5fbands (calledαandß) that hybridize with a single itinerant conduction band. The interaction is given by the direct Coulomb and the Hund's rule exchange terms. Three types of orderings are considered: two conventional spin density waves (SDWs) and an exotic SDW, i.e., with no magnetic moment formation. The conventional SDWs phases, are characterized bymfß>mfαandmfα>mfß, respectively, wheremfαandmfßare the intraband staggered magnetizations. The exotic SDW, which has time reversal symmetry, is described by a purely imaginary order parameter. This phase is related to a band mixing given by the spin-flip part of the Hund's rule exchange interaction. As result, without magnetic field, the phase diagrams of temperature (T) versus pressure (given by the variation of the bandwidth (W)) shows a sequence of phase transitions involving the three phases which gives rise to multicritical points. The presence of the magnetic field (hz) has drastic effects on part of the phase diagram and the location of the multicritical points.

Optical and structural properties of an Eu implanted gallium nitride quantum dots/aluminium nitride superlattice.

GaN/AIN structures made of GaN quantum dots (QDs) separated by AIN spacer layers, were doped with Europium by ion implantation. Rutherford Backscattering/Channelling measurements showed that Eu is incorporated mainly on near-substitutional cation sites within the superlattice region. Only slight deterioration of the crystal quality and no intermixing of the different layers are observed after implantation and annealing. After thermal annealing, photoluminescence associated with Eu3+ ions was observed. From its behaviour under different photon energy excitation and sample temperature we concluded that the Eu-related emitting centres are located inside the GaN QDs or dispersed in the GaN and AIN buffer or spacer layers. The 624 nm PL line, associated with Eu-doped GaN QDs, shows very low thermal quenching, suggesting recombination of confined carriers through rare-earth ion excitation.

Leaf alkaloids, phenolics, and coffee resistance to the leaf miner Leucoptera coffeella (Lepidoptera: Lyonetiidae).

Coffee (Coffea spp.) alkaloids (caffeine and related methylxanthines) and phenolics (caffeic and chlorogenic acids) have recognized pestistatic/pesticidal activity and mediate insect-plant interactions. The present investigation assessed the resistance of 12 coffee genotypes to the leaf miner Leucoptera (= Perileucoptera) coffeella (Guérin-Méneville & Perrottet) (Lepidoptera: Lyonetiidae) and correlated such results with the leaf content of coffee alkaloids and phenolics that probably play a role in the interaction between coffee and this leaf miner. The levels of chlorogenic and caffeic acid, caffeine, and related methylxanthines were measured and quantified in leaf extracts of these genotypes before and 7 d after their infestation by the leaf miner. Some coffee genotypes (Coffea canephora L. and Coffea racemosa Lour. and its hybrids with Coffea arabica L.) exhibited high pesticidal activity (100% mortality) toward the L. coffeella, indicating their antibiosis resistance. However, there was no correlation between this activity and the leaf levels of coffee alkaloids and phenolics. Curiously, infestation by L. coffeella leads to a nearly four-fold decline in the leaf levels of chlorogenic acid, which does not affect this pest species but may affect other generalist species. Indeed, chlorogenic acid sprayed on coffee leaves stimulated locomotory activity of the green scale Coccus viridis (Green) (Hemiptera: Coccidae), thus minimizing their feeding in contrast with the absence of this polyphenol. Therefore, reduction of chlorogenic acid levels in coffee leaves due to leaf miner infestation seems to also favor infestation by generalist insects, such as the green scale.

Field-induced glassy state in disordered cluster antiferromagnets.

We investigate the role of antiferromagnetic spin clusters on the glassiness induced by uniform and random fields. We consider an antiferromagnetic disordered model that is treated within the replica method, resulting in an effective single-cluster problem. Our results show that regimes of weak and intermediate disorder are suitable for highly unusual phenomena. For the case of a uniform field, cluster polarization can favor a cluster spin-glass state, i.e. the magnetic field increases the freezing temperature at intermediate disorders. In addition, random fields introduce local perturbations that allow uncompensated cluster states, supporting cluster freezing even at very weak disorders. The theoretical framework presented here can be useful for the understanding of phenomena observed in magnetic glassy systems that have spin clusters as building blocks instead of individual spins. In particular, we suggest that our results can help to explain the magnetic behaviour of the rare earth TbIn0.99Mn0.01O3, which has been recently proposed to be composed of antiferromagnetic clusters, presenting a field-induced increase of the freezing temperature.

Enhancement of the spin-orbit coupling by strong electronic correlations in transition metal and light actinide compounds.

A simple variational argument is presented which indicates that the spin-orbit coupling in itinerant systems can be enhanced by strong electronic correlations. The importance of the enhancement in the formation of the giant magnetic anisotropy found in the metallic paramagnetic and magnetically ordered states of compounds containing transition metal and light actinide elements (such as tetragonal Sr2RhO4, Sr2IrO4, the cubic uranium monochalcogenides and tetragonal URu2Si2) is discussed.

Therapeutic and Preventive Effect of Voluntary Running Wheel Exercise on Social Defeat Stress (SDS)-induced Depressive-like Behavior and Chronic Pain in Mice.

Major depressive disorders (MDD) and chronic pain (CP) affect significant portion of the world's population and have high comorbidity rate. Social defeat stress (SDS) model was standardized in mice and can trigger depressive-like behavior and chronic pain. Based especially on clinical trials showing an effective preventive and therapeutic effect of physical exercise on CP and symptoms associated with MDD, this study aimed to investigate if the voluntary running wheel exercise can exert these effects in mice submitted to the 10-day SDS protocol, using fluoxetine as positive control. For this, we ran two set of experiments: in the first set mice started performing voluntary running wheel exercise after submitted to SDS and, in the second set, mice performed voluntary running wheel exercise before and during SDS. Mechanical and chemical hyperalgesia was analyzed through electronic von Frey and capsaicin test, respectively. Depressive-like behavior was assessed through social interaction test. Our results showed that the voluntary running wheel exercise was more effective than fluoxetine reversing the SDS-induced persistent hyperalgesia and both, fluoxetine and voluntary running wheel exercise, was effective reversing SDS-induced social avoidance. Also, voluntary running wheel exercise is an effective tool preventing both hyperalgesia and social avoidance induced by SDS. To the best of our knowledge, this was the first study using physical exercise as a therapeutic and preventive tool for chronic pain and depressive-like behavior simultaneously induced by social stress.

Social stress as a trigger for depressive-like behavior and persistent hyperalgesia in mice: study of the comorbidity between depression and chronic pain.

BACKGROUND: There is great comorbidity and similarity between chronic pain and major depressive disorders. We have recently shown that 10 days of social defeat stress (SDS) induces hyperalgesia regardless depressive-like behavior in mice. Here we aimed to investigate whether social stress predisposes to chronic pain and, inversely, whether chronic pain predisposes to stress-induced depression. METHODS: Firstly, we used the 10 days SDS paradigm in mice followed by a mild protocol of repetitive inflammatory stimulus to evaluate if SDS would predispose to persistent hyperalgesia development. Secondly, we used the intense protocol of repetitive inflammatory stimulus followed by a subthreshold SDS to evaluate if persistent hyperalgesia would predispose to depressive-like behavior of social avoidance. RESULTS: Our results showed that SDS predispose to chronic pain, since stressed mice injected with PGE2 for 7 days (mild protocol), stimuli normally not sufficient to trigger chronic pain, showed persistent hyperalgesia. Also, we showed that persistent hyperalgesia induced by repetitive inflammatory stimuli predispose to long-lasting depressive-like behavior of social avoidance induced by subthreshold SDS. LIMITATIONS: We did not analyze molecular mechanism associated with chronic pain and depressive-like behavior induced by SDS. However, we hypothesized that SDS and 14 days of PGE2 would generate neuroplasticity on brain areas shared by chronic pain and depression, predisposing to pain chronification and depressive-like behavior, respectively. CONCLUSIONS: We can conclude social stress as a key and a common factor for chronic pain and depression. We can also conclude that SDS predisposes to chronic pain and, inversely, chronic pain predisposes to depressive-like behavior.