Acute aquatic toxicity of arsenic-based chemical warfare agents to Daphnia magna

Sea dumping of chemical warfare (CW) took place worldwide during the 20th century. Submerged CW included metal bombs and casings that have been exposed for 50-100 years of corrosion and are now known to be leaking. Therefore, the arsenic-based chemical warfare agents (CWAs), pose a potential threat to the marine ecosystems. The aim of this research was to support a need for real-data measurements for accurate risk assessments and categorization of threats originating from submerged CWAs. This has been achieved by providing a broad insight into arsenic-based CWAs acute toxicity in aquatic ecosystems. Standard tests were performed to provide a solid foundation for acute aquatic toxicity threshold estimations of CWA: Lewisite, Adamsite, Clark I, phenyldichloroarsine (PDCA), CWA-related compounds: TPA, arsenic trichloride and four arsenic-based CWA degradation products. Despite their low solubility, during the 48 h exposure, all CWA caused highly negative effects on Daphnia magna. PDCA was very toxic with 48 h D. magna LC50 at 0.36 mu g x L-1- and Lewisite with EC50 at 3.2 mu g x L-1 . Concentrations at which no immobilization effects were observed were slightly above the analytical Limits of Detection (LOD) and Quantification (LOQ). More water-soluble CWA degradation products showed no effects at concentrations up to 100 mg x L-1.Peer reviewe

Salvinorin A analogues PR-37 and PR-38 attenuate compound 48/80-induced itch responses in mice: Salvinorin A analogues PR-37 and PR-38 in pruritus

The opioid system plays a crucial role in several physiological processes in the CNS and in the periphery. It has also been shown that selective opioid receptor agonists exert potent inhibitory action on pruritus and pain. In this study we examined whether two analogues of Salvinorin A, PR-37 and PR-38, exhibit antipruritic properties in mice

Oxr1 Is Essential for Protection against Oxidative Stress-Induced Neurodegeneration

Oxidative stress is a common etiological feature of neurological disorders, although the pathways that govern defence against reactive oxygen species (ROS) in neurodegeneration remain unclear. We have identified the role of oxidation resistance 1 (Oxr1) as a vital protein that controls the sensitivity of neuronal cells to oxidative stress; mice lacking Oxr1 display cerebellar neurodegeneration, and neurons are less susceptible to exogenous stress when the gene is over-expressed. A conserved short isoform of Oxr1 is also sufficient to confer this neuroprotective property both in vitro and in vivo. In addition, biochemical assays indicate that Oxr1 itself is susceptible to cysteine-mediated oxidation. Finally we show up-regulation of Oxr1 in both human and pre-symptomatic mouse models of amyotrophic lateral sclerosis, indicating that Oxr1 is potentially a novel neuroprotective factor in neurodegenerative disease

Persistent Exposure to Mycoplasma Induces Malignant Transformation of Human Prostate Cells

Recent epidemiologic, genetic, and molecular studies suggest infection and inflammation initiate certain cancers, including those of the prostate. The American Cancer Society, estimates that approximately 20% of all worldwide cancers are caused by infection. Mycoplasma, a genus of bacteria that lack a cell wall, are among the few prokaryotes that can grow in close relationship with mammalian cells, often without any apparent pathology, for extended periods of time. In this study, the capacity of Mycoplasma genitalium, a prevalent sexually transmitted infection, and Mycoplasma hyorhinis, a mycoplasma found at unusually high frequency among patients with AIDS, to induce a malignant phenotype in benign human prostate cells (BPH-1) was evaluated using a series of in vitro and in vivo assays. After 19 weeks of culture, infected BPH-1 cells achieved anchorage-independent growth and increased migration and invasion. Malignant transformation of infected BPH-1 cells was confirmed by the formation of xenograft tumors in athymic mice. Associated with these changes was an increase in karyotypic entropy, evident by the accumulation of chromosomal aberrations and polysomy. This is the first report describing the capacity of M. genitalium or M. hyorhinis infection to lead to the malignant transformation of benign human epithelial cells and may serve as a model to further study the relationship between prostatitis and prostatic carcinogenesis

Proteomic and Physiological Responses of Kineococcus radiotolerans to Copper

Copper is a highly reactive, toxic metal; consequently, transport of this metal within the cell is tightly regulated. Intriguingly, the actinobacterium Kineococcus radiotolerans has been shown to not only accumulate soluble copper to high levels within the cytoplasm, but the phenotype also correlated with enhanced cell growth during chronic exposure to ionizing radiation. This study offers a first glimpse into the physiological and proteomic responses of K. radiotolerans to copper at increasing concentration and distinct growth phases. Aerobic growth rates and biomass yields were similar over a range of Cu(II) concentrations (0–1.5 mM) in complex medium. Copper uptake coincided with active cell growth and intracellular accumulation was positively correlated with Cu(II) concentration in the growth medium (R2 = 0.7). Approximately 40% of protein coding ORFs on the K. radiotolerans genome were differentially expressed in response to the copper treatments imposed. Copper accumulation coincided with increased abundance of proteins involved in oxidative stress and defense, DNA stabilization and repair, and protein turnover. Interestingly, the specific activity of superoxide dismutase was repressed by low to moderate concentrations of copper during exponential growth, and activity was unresponsive to perturbation with paraquot. The biochemical response pathways invoked by sub-lethal copper concentrations are exceptionally complex; though integral cellular functions are preserved, in part, through the coordination of defense enzymes, chaperones, antioxidants and protective osmolytes that likely help maintain cellular redox. This study extends our understanding of the ecology and physiology of this unique actinobacterium that could potentially inspire new biotechnologies in metal recovery and sequestration, and environmental restoration

Whole organisms or pure compounds? entourage effect versus drug specificity

As the therapeutic use of sacred plants and fungi becomes increasingly accepted by Western medicine, a tug of war has been taking place between those who advocate the traditional consumption of whole organisms and those who defend exclusively the utilization of purified compounds. The attempt to reduce organisms to single active principles is challenged by the sheer complexity of traditional medicine. Ayahuasca, for example, is a concoction of at least two plant species containing multiple psychoactive substances with complex interactions. Similarly, cannabis contains dozens of psychoactive substances whose specific combinations in different strains correspond to different types of therapeutic and cognitive effects. The “entourage effect” refers to the synergistic effects of the multiple compounds present in whole organisms, which may potentiate clinical efficacy while attenuating side effects. In opposition to this view, mainstream pharmacology is adamant about the need to use purified substances, presumably more specific and safe. In this chapter, I will review the evidence on both sides to discuss the scientific, economic, and political implications of this controversy. The evidence indicates that it is time to embrace the therapeutic complexity of psychedelics.2019-07-3

CVD Diamond Films Quality Characterization by ESR, SEM and Raman Spectroscopy

Polycrystalline diamond films were deposited by electron assisted hot filament chemical vapor deposition method on (001) Si substrate using a mixture of propane-butane and hydrogen as working gas. In morphology investigation of diamond films using scanning electron microscope, it was found that diamond film morphology is changing from (111), for hydrocarbon concentration below 0.5 vol.%, via (100) to the so-called "ball-like" structure. The diamond film quality and defect structures in it were investigated by Raman and electron spin resonance spectroscopy for the purpose of obtaining basic knowledge which will aid the growth of defect free epitaxial diamond film for electronic and optical applications

Badanie jakościowe materiałów węglowych za pomocą spektroskopii Ramana

Praca ta prezentuje możliwość zastosowania spektroskopii Ramana do badań jakościowych materiałów węglowych typu DLC (diamond-like carbon). Badania zmiany parametrów spektralnych pasm charakterystycznych D i G w zakresie od temperatury pokojowej do 300°C umożliwiły obserwację wpływu procesu wygrzewania na przechodzenie materiału z formy węgla amorficznego do formy zbliżonej do nanokrystalicznego grafitu

Zmienność przestrzenna zawartości azotu ogółem w poziomie powierzchniowym w skali pola produkcyjnego

Soil total nitrogen does not come under so great temporal changes as its mineral forms, but it could be spatially differentiated. Spatial variability of total nitrogen could occur in the region scale as well as in the microscale that is to say within production field scale. For agricultural practice very important is to know spatial variability of its nitrogen form in the field scale since it could be very important to optimization of fertilization. That is why the objective of this study was to estimate total nitrogen spatial variability in the field scale. To this end 16.5 hectare field after winter wheat cultivation was chosen and soil samples from 47 individual points were collected in spring every 50 m. Total nitrogen was determined by Kjeldahl method. On the basis of total N content results empirical variograms were drawn with SURFER 8.0 software. On the ground of variograms, mathematical models and raster maps illustrating the distribution of investigated total nitrogen content in the field scale were drown. Basic statistic calculations were done with the use of STATISTICA 8.0 software. Results showed differentiated concentration of total nitrogen content in the humic horizon of investigated soil (0.78–1.11 g kg–1). Small differentiation of determined nitrogen could be confirmed by low standard deviation (0.078) and low correlation coefficients (8.44 %). Geostatistical analysis proved that surface layer nitrogen did not occur full dispersion what was confirmed by nugget effect amounting 0.001 (g/kg)2 with the sill variance accounted for 0.006 (g/kg)2. The large range of 212 m evidenced that the correlation between total nitrogen content is bigger than distances between samples points. Proper adjustment of models (spherical and nugget effect) was confirmed also by the variance calculated (0.006 [g/kg]2), similar to sill variance defined on the ground of those models.Azot ogółem w glebach nie podlega tak dużym zmianom w czasie jak jego formy mineralne, ale jego zawartość może być zróżnicowana przestrzennie. To zróżnicowanie może występować w makroskali np. regionu, jak i w mikroskali, czyli w obrębie pola produkcyjnego. Dla praktyki rolniczej szczególnie ważne jest poznanie zmienności tej formy azotu na obszarze pola, gdyż może to być pomocne przy optymalizacji nawożenia. Dlatego też celem niniejszej pracy było oszacowanie zmienności przestrzennej azotu ogółem w obrębie pola uprawnego. Do tego celu wytypowano pole po pszenicy ozimej o powierzchni 16,5 ha, z którego wiosną pobrano próbki z 47 punktów rozmieszczonych co 50 m. Azot ogółem oznaczono metodą Kjeldahla. Na podstawie otrzymanych wyników przy zastosowaniu programu SURFER 8.0 wykreślono wariogram empiryczny, który posłużył do stworzenia modelu i wykreślenia mapy rastrowej obrazującej rozkład badanej formy azotu w obrębie pola. Wykonano również obliczenia statystyczne przy użyciu programu STATISTIKA 8.0. Przeprowadzone badanie wykazały zróżnicowaną zawartość azotu ogółem w poziomie próchnicznym (0,78–1,11 g kg–1). O niewielkim zróżnicowaniu analizowanego parametru może świadczyć mała wartość odchylenia standardowego (0,078) oraz mały współczynnik zmienności (8,44 %). Przeprowadza analiza wykazała, że azot w poziomie powierzchniowym nie występuje w pełnym rozproszeniu, o czym świadczy występowanie efektu samorodka, który dla badanej cechy wynosił 0,001 (g/kg)2 przy wariancji progowej wynoszącej 0,006 (g/kg)2. Duży zasięg wynoszący 212 m świadczy o skorelowaniu zawartości azotu ogółem na odległości większe niż odległości między punktami pobierania próbek. Dobre dopasowanie modeli (sferycznego i efektu samorodka) potwierdza również wariancja obliczona 0,006 (g/kg)2, która jest zbliżona do wariancji progowej odczytanej na podstawie tych modeli