Synthesis, structural characterization and antiproliferative and toxic bio-activities of copper(II) and nickel(II) citronellal N-ethylmorpholine thiosemicarbazonates

This paper reports the syntheses and characterization of ethylmorpholine substituted citronellal thiosemicarbazone copper(II) and nickel(II) metal complexes. The compounds were characterized through elemental analyses and spectroscopic (IR, UV-Vis, NMR, MS) methods. The X-ray analysis of the two complexes shows that both Ni and Cu derivatives present a square planar coordination, where the coordinating homologous donor atoms bind in trans to each other. The compounds were tested for their biological activity after determination of their octanol-saline partition coefficients, followed by their radical scavenging properties. Eventually the complexes were tested for their proliferation inhibition on human histiocytic lymphoma U937 cell line. The GI₅₀ values resulted to be 2.3 μM for the copper derivative and 12.3 μM for the nickel derivative.     

Preliminary study of mother–offspring conflict in black and gold howler monkeys (<Emphasis Type=Italic>Alouatta caraya</Emphasis>)

Parent–offspring conflict has been scarcely studied in Neotropical primates. In this study, we explored mother–offspring conflict in a group of wild black and gold howler monkeys (Alouatta caraya) in northeastern Argentina. We used the all-occurrences technique to record behaviors, completing 712 h of observation. The results showed that all immature individuals between 2 and 23 months expressed conflict with regard to suckling or traveling with their mothers. Successful suckling attempts negatively correlated with the age of the immatures, occurring least frequently with the presence of newborns. In the juvenile period, the decline in successful attempts was a consequence of juveniles reducing suckling attempts and mother rejection.     

Short term regulation of acyl CoA: Cholesterol acyl transferase (ACAT) activity in the regenerating and perinatal liver

Acyl coenzyme A:cholesterol acyltransferase (ACAT), the enzyme catalyzing the hepatic cholesterol esterification could be involved in the modified availability of cholesterol detectable in proliferating systems. While no significant variations are detectable in the regenerating liver, the modified ACAT activity during liver development and its differential sensitivity to the in vitro stimulation of modulatory systems suggest an involvement of the enzyme in this proliferating process.     

Linear sesterterpenes from the Caribbean sponge Thorecta horridus with inflammatory activity

Two new linear sesterterpenes 1 and 2, containing an α,β-unsaturated γ-lactone ring, have been isolated from the Caribbean sponge Thorecta horridus, Hyatt 1877 (F. Thorectidae). The structures of the two new metabolites were established on the basis of spectral data including 2D NMR experiments. Compound 1 exhibits inflammatory activity.Structures of two new linear sesterterpenes 1 and 2 from the sponge Thorecta horridus, determined through HREIMS, 1D and 2D NMR experiments, are reported. Compound 1 exhibits inflammatory activity.     

Habitat fragmentation reduces plant progeny quality: a global synthesis

Most of the world's land surface is currently under human use and natural habitats remain as fragmented samples of the original landscapes. Measuring the quality of plant progeny sired in these pervasive environments represents a fundamental endeavour for predicting the evolutionary potential of plant populations remaining in fragmented habitats and thus their ability to adapt to changing environments. By means of hierarchical and phylogenetically independent meta‐analyses we reviewed habitat fragmentation effects on the genetic and biological characteristics of progenies across 179 plant species. Progeny sired in fragmented habitats showed overall genetic erosion in contrast with progeny sired in continuous habitats, with the exception of plants pollinated by vertebrates. Similarly, plant progeny in fragmented habitats showed reduced germination, survival and growth. Habitat fragmentation had stronger negative effects on the progeny vigour of outcrossing‐ than mixed‐mating plant species, except for vertebrate‐pollinated species. Finally, we observed that increased inbreeding coefficients due to fragmentation correlated negatively with progeny vigour. Our findings reveal a gloomy future for angiosperms remaining in fragmented habitats as fewer sired progeny of lower quality may decrease recruitment of plant populations, thereby increasing their probability of extinction.     

Optimising predictive modelling of Ross River virus using meteorological variables

BackgroundStatistical models are regularly used in the forecasting and surveillance of infectious diseases to guide public health. Variable selection assists in determining factors associated with disease transmission, however, often overlooked in this process is the evaluation and suitability of the statistical model used in forecasting disease transmission and outbreaks. Here we aim to evaluate several modelling methods to optimise predictive modelling of Ross River virus (RRV) disease notifications and outbreaks in epidemiological important regions of Victoria and Western Australia.Methodology/Principal findingsWe developed several statistical methods using meteorological and RRV surveillance data from July 2000 until June 2018 in Victoria and from July 1991 until June 2018 in Western Australia. Models were developed for 11 Local Government Areas (LGAs) in Victoria and seven LGAs in Western Australia. We found generalised additive models and generalised boosted regression models, and generalised additive models and negative binomial models to be the best fit models when predicting RRV outbreaks and notifications, respectively. No association was found with a model’s ability to predict RRV notifications in LGAs with greater RRV activity, or for outbreak predictions to have a higher accuracy in LGAs with greater RRV notifications. Moreover, we assessed the use of factor analysis to generate independent variables used in predictive modelling. In the majority of LGAs, this method did not result in better model predictive performance.Conclusions/SignificanceWe demonstrate that models which are developed and used for predicting disease notifications may not be suitable for predicting disease outbreaks, or vice versa. Furthermore, poor predictive performance in modelling disease transmissions may be the result of inappropriate model selection methods. Our findings provide approaches and methods to facilitate the selection of the best fit statistical model for predicting mosquito-borne disease notifications and outbreaks used for disease surveillance.     

Exploration of the Acetylcholinesterase Inhibitory Activity of Some Alkaloids from <Emphasis Type="Italic">Amaryllidaceae</Emphasis> Family by Molecular Docking In Silico

Alzheimer’s disease (AD) is a progressive condition, where dementia symptoms gradually worsen. Biochemically the disease is characterized by the presence of neuritic plaques, neurofibrillary tangles, in addition to cholinergic dysfunction in the central nervous system. The role of the cholinergic neurotransmission in AD is the basis of the widely accepted cholinergic hypothesis. Some of the most relevant therapies for the treatment of the disease are based on the acetylcholinesterase (AChE) inhibitor activity; however, these therapies are not effective to stop the disease progression, but only can temporarily slow down the worsening of dementia symptoms, and improve quality of life of patients and their caregivers. In recent years, plant alkaloids extracted from Amaryllidaceae family have received great attention due to the well-known anti cholinergic activity. In this context, the purpose of this study was to apply the docking molecular in sílico analysis aiming to examine the recombinant human AChE enzyme (rhAChE) inhibitory activity displayed by different alkaloids from Amaryllidaceae family. Overall, the present results support the idea that alkaloids reported in this research are capable of interacting with rhAChE-binding sites.     

The role of Pannexin-1 channels and extracellular ATP in the pathogenesis of the human immunodeficiency virus

Only recently, the role of large ionic channels such as Pannexin-1 channels and Connexin hemichannels has been implicated in several physiological and pathological conditions, including HIV infection and associated comorbidities. These channels are in a closed stage in healthy conditions, but in pathological conditions including HIV, Pannexin-1 channels and Connexin hemichannels become open. Our data demonstrate that acute and chronic HIV infection induces channel opening (Pannexin and Connexin channels), ATP release into the extracellular space, and subsequent activation of purinergic receptors in immune and non-immune cells. We demonstrated that Pannexin and Connexin channels contribute to HIV infection and replication, the long-term survival of viral reservoirs, and comorbidities such as NeuroHIV. Here, we discuss the available data to support the participation of these channels in the HIV life cycle and the potential therapeutic approach to prevent HIV-associated comorbidities.     

Participation of nitric oxide in the color change induced by UV radiation in the crab Chasmagnathus granulatus

The ability of UV radiation to stimulate color change in vertebrates is well known; however, the signaling pathway involved is not fully explained. Since nitric oxide (NO) is among the candidates for this role, in this study the participation of NO signaling in the pigment migration induced by UV radiation in melanophores of the crab Chasmagnathus granulatus was investigated. When the NO donor, SIN-1, was incubated with pieces of epidermis, there was an induction of a dose-dependent pigment dispersion (in vitro assays). When male adults were exposed to different doses of UVA and UVB, N(G)-nitro-l-arginine-methyl-ester, an NO synthase (NOS) blocker produced a decrease of the pigment dispersion induced by UV (in vivo assays). However, in similar assays, 2-phenyl-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide, an NO scavenger, decreased only the pigment dispersion induced by UVA. Interestingly, buthionine sulfoximine did not produce any change in pigment dispersion induced by UVA (in vivo assays) and SIN-1 (in vitro assays). Our results using NADPH-diaphorase histochemistry and immunocytochemistry against nNOS indicated the production of NO by epidermal cells. In conclusion, we suggest that NO is a key molecule for the induction of pigment dispersion in the melanophores of Chasmagnthus granulatus, and also that NOS activation is a fundamental step for this process.