488 research outputs found
Ziram, a dithiocarbamate fungicide, exhibits pseudo-cytoprotective actions against oxidative stress in rat thymocytes : Possible environmental risks
Ziram, a dithiocarbamate fungicide, protects various vegetables and fruits against infections by fungus. Recently, there have been increasing anxieties about the risks in the use of dithiocarbamate fungicides. Our previous studies showed that Zn2+ was a determinant of Ziram cytotoxicity. In addition, Zn2+ is linked to H2O2 cytotoxicity. Therefore, in this study, we aimed to test the hypothesis that Ziram could augment the cytotoxicity of H2O2 by examining the changes induced by Ziram in some cellular parameters in rat thymic lymphocytes subjected to H2O2-induced oxidative stress using flow-cytometric methods with fluorescent dyes. Ziram significantly attenuated H2O2-induced cell death at sublethal concentrations. However, in the cells under oxidative stress elicited by H2O2, Ziram promoted the changing over from intact cells to living cells with exposed phosphatidylserine (PS) on plasma membranes, whereas it inhibited the transition from PS-exposed living cells to dead cells. Ziram significantly augmented H2O2 actions, including reduction of cellular glutathione levels and elevation of intracellular Zn2+ concentrations. Conversely, it attenuated H2O2-induced depolarization of mitochondrial membrane potential. Ziram at sublethal concentrations seems to exhibit promotive and suppressive actions on the process of cell death caused by H2O2. Ziram increased the number of living cells with exposed PS, a phenomenon characteristic of early stages of apoptosis. Thus, it is concluded that Ziram exhibits pseudo-cytoprotective actions against H2O2- induced oxidative stress
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Pharmacotherapy in patients with epilepsy and psychosis.
The recognition and treatment of psychosis in persons with epilepsy (PWE) is recommended with the apparent dilemma between treating psychosis and opening the possibility of exacerbating seizures. The pooled prevalence estimate of psychosis in PWE is 5.6%. It has been proposed that a 'two hit' model, requiring both aberrant limbic activity and impaired frontal control, may account for the wide range of clinical phenotypes. The role of antiepileptic drugs in psychosis in PWE remains unclear. Alternating psychosis, the clinical phenomenon of a reciprocal relationship between psychosis and seizures, is unlikely to be an exclusively antiepileptic drug-specific phenomenon but rather, linked to the neurobiological mechanisms underlying seizure control. Reevaluation of antiepileptic treatment, including the agent/s being used and degree of epileptic seizure control is recommended. The authors found very few controlled studies to inform evidence-based treatment of psychosis in PWE. However, antipsychotics and benzodiazepines are recommended as the symptomatic clinical treatments of choice for postictal and brief interictal psychoses. The general principle of early symptomatic treatment of psychotic symptoms applies in epilepsy-related psychoses, as for primary psychotic disorders. In the authors' experience, low doses of antipsychotic medications do not significantly increase clinical risk of seizures in PWE being concurrently treated with an efficacious antiepileptic regimen
Zinc is a determinant of the cytotoxicity of Ziram, a dithiocarbamate fungicide, in rat thymic lymphocytes : Possible environmental risk
Ziram, one of dithiocarbamate fungicides, is widely applied to agriculture because the agent protects various crops from fungal infections. Risks of dithiocarbamate biocide use are concerned. It was previously reported that Ziram increased the intracellular concentration of Zn2+. Therefore, we cytometrically studied the mechanism of Zn2+-dependent lethal actions of Ziram on rat lymphocytes under environmentally relevant Zn2+ levels. Membrane and cellular parameters of rat lymphocytes were estimated by flow-cytometric techniques with appropriate fluorescent probes. The Ziram-induced increase in cell lethality was completely attenuated by Zn2+ chelators. A significant raise of cell lethality was found on the simultaneous application of Ziram at a sublethal concentration and ZnCl2. The combination of Ziram and ZnCl2 increased the cellular superoxide anion content and decreased the cellular GSH content, which possibly caused the increase in cell lethality. The zinc concentrations under present experimental conditions were comparable to the environmentally relevant concentrations found in rivers. Therefore, the environmental level of zinc may be critical in estimating the toxicity of Ziram to wild animals
Co-variation of fish and coral traits in relation to habitat type and fishery status
Escalating climate impacts on coral reefs are increasingly expanding management goals beyond preserving biodiversity to also maintaining ecosystem functions. Morphological and ecological species traits can help assess changes within reef communities beyond taxonomic identities alone. However, our limited understanding of trait interactions between habitat-building corals and associated reef fishes and whether they are captured by current monitoring practices hampers management. Here, we apply co-inertia analyses to test whether trait assemblages in corals and fishes co-vary across different habitats and test whether different components of the reef fish community (fisheries vs. non-target species) display distinct relationships. We find that spatial co-variation across habitat types between coral and fish traits is strengthened by the addition of non-target fishes. Additionally, even in fisheries with diverse targets, non-target species make unique contributions to the overall trait structure and highlight the importance of considering monitoring protocols when drawing conclusions about traits and ecosystems
Noninvasive prediction of shunt operation outcome in idiopathic normal pressure hydrocephalus
Idiopathic normal pressure hydrocephalus (iNPH) is a syndrome characterized by gait disturbance, cognitive deterioration and urinary incontinence in elderly individuals. These symptoms can be improved by shunt operation in some but not all patients. Therefore, discovering predictive factors for the surgical outcome is of great clinical importance. We used normalized power variance (NPV) of electroencephalography (EEG) waves, a sensitive measure of the instability of cortical electrical activity, and found significantly higher NPV in beta frequency band at the right fronto-temporo-occipital electrodes (Fp2, T4 and O2) in shunt responders compared to non-responders. By utilizing these differences, we were able to correctly identify responders and non-responders to shunt operation with a positive predictive value of 80% and a negative predictive value of 88%. Our findings indicate that NPV can be useful in noninvasively predicting the clinical outcome of shunt operation in patients with iNPH
Predominant sarcomatoid carcinoma of the lung concurrent with jejunal metastasis and leukocytosis
Sarcomatoid carcinoma is an extremely rare biphasic tumor characterized by a combination of malignant epithelial and mesenchymal cells. Limited data on sarcomatoid carcinoma showed that most cases occurred with advanced local disease and metastasis, and paraneoplastic syndromes were rare. We present the case of a 63-year-old man with lung
sarcomatoid carcinoma associated with jejunum metastasis and leukocytosis, and its clinical, macroscopic, and histopathological features. This case emphasizes the importance of recognizing paraneoplastic syndromes and metastasis of sarcomatoid carcinoma at diagnosis
Scale-free memory model for multiagent reinforcement learning. Mean field approximation and rock-paper-scissors dynamics
A continuous time model for multiagent systems governed by reinforcement
learning with scale-free memory is developed. The agents are assumed to act
independently of one another in optimizing their choice of possible actions via
trial-and-error search. To gain awareness about the action value the agents
accumulate in their memory the rewards obtained from taking a specific action
at each moment of time. The contribution of the rewards in the past to the
agent current perception of action value is described by an integral operator
with a power-law kernel. Finally a fractional differential equation governing
the system dynamics is obtained. The agents are considered to interact with one
another implicitly via the reward of one agent depending on the choice of the
other agents. The pairwise interaction model is adopted to describe this
effect. As a specific example of systems with non-transitive interactions, a
two agent and three agent systems of the rock-paper-scissors type are analyzed
in detail, including the stability analysis and numerical simulation.
Scale-free memory is demonstrated to cause complex dynamics of the systems at
hand. In particular, it is shown that there can be simultaneously two modes of
the system instability undergoing subcritical and supercritical bifurcation,
with the latter one exhibiting anomalous oscillations with the amplitude and
period growing with time. Besides, the instability onset via this supercritical
mode may be regarded as "altruism self-organization". For the three agent
system the instability dynamics is found to be rather irregular and can be
composed of alternate fragments of oscillations different in their properties.Comment: 17 pages, 7 figur
Right ventricular dysfunction in patients with Brugada-like electrocardiography: a two dimensional strain imaging study
<p>Abstract</p> <p>Background</p> <p>Sodium channel blockers augment ST-segment elevation in the right precordial leads in patients undergoing Brugada-type electrocardiography (ECG). However, their effect on echocardiographic features is not known. We address this by assessing global and regional ventricular function using conventional Doppler and two- dimensional (2D) speckle tracking techniques.</p> <p>Methods</p> <p>Thirty-one patients with Brugada-type ECG were studied. A pure sodium channel blocker, pilsicainide, was used to provoke an ECG response. The percentage longitudinal systolic myocardial strain at the base of both the right ventricular (RV) free wall and the interventricular septum wall was measured using 2D speckle tracking. Left ventricular (LV) and RV myocardial performance (TEI) indices were also measured.</p> <p>Results</p> <p>The pilsicainide challenge provoked a positive ECG response in 13 patients (inducible group). In the inducible group, longitudinal strain was significantly reduced only at the RV (-27.3 ± 5.4% vs -22.1 ± 3.6%, <it>P </it>< 0.01), and both RV and LV TEI indices increased (RV: 0.19 ± 0.09 vs 0.27 ± 0.11, <it>P </it>< 0.05; LV: 0.30 ± 0.10 vs 0.45 ± 0.10, <it>P </it>< 0.01) after pilsicainide administration.</p> <p>Conclusions</p> <p>Temporal and spatial analysis using the TEI index and 2D strain imaging revealed the deterioration of global ventricular function associated with conduction disturbance and RV regional function in patients with Brugada-type ECG and coved type ST elevation due to administration of a sodium channel blocker.</p
Mapping potential conflicts between global agriculture and terrestrial conservation
Industrial EcologyEnvironmental Biolog
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