Factors influencing the diurnal behaviour of white rhino (Ceratotherium simum) in Matobo National Park,Zimbabwe

Activity periods and diurnal behaviour of southern white rhino (Ceratotherium simum simum) were studied in Matobo National Park, Zimbabwe, from August 2016 to July 2017 using camera trapping and focal group sampling, respectively. Camera trap data showed that diurnal and nocturnal movements of white rhino varied significantly with moon phase, with more frequent nocturnal photographic captures during full- and third-quarter moon phases than during new and crescent moon phases. Permutational MANOVA and canonical correspondence analysis of focal group observation data were used to test the effects of season, time of day, habitat type, distance to roads, moon phase, presence/absence of other mammals, age/sex category, individual identity and herd composition on daytime behaviour. Weather conditions accounted for the majority of variation in rhino behaviour, with more time spent feeding during cloudy and rainy weather than sunny weather. Time of day and moon phase also accounted for high variation in behaviour, followed by habitat attributes and age/sex category. Variance partitioning by sets of explanatory variables showed that weather conditions had the greatest explanatory power in the variation of rhino behaviour, followed by temporal attributes, habitat attributes and age/sex category. Our findings provide insights for white rhino population management strategies aimed at increasing the effectiveness of security patrols, minimising disturbance and improving sightings for tourists.     

Psychiatric disorders and SLC6A4 gene variants: possible effects on alcohol dependence and alzheimer’s disease

Molecular Biology Reports - Serotoninergic system is one of the most important neurotransmission systems investigated in the field of psychiatry. Extensive evidence reveals how alterations of this...     

Janus kinase inhibitors role in bone remodeling

Janus kinases (JAKs) play a pleiotropic role in several important physiological processes, such as cell maturation, cell proliferation, and cell death, via providing transmission signals from several molecules, such as cytokines, interferons, hormones, and growth factors, to the nucleus. Bone physiology and remodeling are markedly influenced by proinflammatory cytokines. Among them, interleukin-1 (IL-1) and IL-6 are considered potent stimulator of bone resorption. Several cytokine receptors, such as IL-6 receptors, are characterized by tyrosine kinases of the JAK family associated with their intracellular domains. There is an emerging interest in the effects of JAKs inhibition on the cells involved in bone remodeling. JAK inhibitors represent a new class of molecules involved in the therapy of numerous immune-mediated inflammatory diseases. In this review, we want to focus on the role of JAKs inhibitors on bone remodeling and on RANKL-RANK-OPG signal and inflammatory cytokines which are involved in the regulation of bone cells, such as osteoblasts and osteoclasts.     

The molecular markers of cancer stem cells in head and neck tumors

Head and neck cancer (HNC) is the six most common malignancy worldwide leading to more than 350,000 deaths annually. Despite recent advances in treatment modalities for these patients, there has been only a slight improvement of prognosis. As cancer stem cells (CSCs) have been implicated in tumor cell survival, progression, and response to therapy, the identification of this tumor subpopulation would have important therapeutic and prognostic implications. In this structured appraisal of the literature, Embase, PubMed, and Ovid were searched for publications that investigated CSC markers of HNC in humans. The search was conducted under the PRISMA guidelines with clear inclusion and exclusion criteria for articles published in the last two decades. The review process resulted in the identification of some key CSC-associated molecules such as CD44, ALDH1, CD133, Oct3/4, Nanog, and Sox2, although a single common CSC sorting marker could not be found. These biomarkers were identified in a range of HNCs but the most common one was squamous cell carcinoma (SCC), predominantly oral SCC. Patient cohorts were of variable size (3–195 individuals) and the most common technique used for detection was immunohistochemistry. Some of the molecules were associated with poor prognosis and may be able to inform the choice of appropriate treatment for these patients.     

Circadian emergence and movement of captive juvenile tuatara (Sphenodon spp.)

Abstract

Knowledge of the circadian behaviour of young tuatara (Sphenodon spp.) is relatively scarce because tuatara are difficult to observe in the wild. We document diurnal, nocturnal and crepuscular emergence and movements (half‐body movement, walking and running) of three groups of captive juvenile tuatara (2‐ and 3‐year‐old Sphenodon guntheri, and 5‐year‐old S. punctatus). Juvenile tuatara emerge predominantly at night, but move around above ground, mainly during the day and around sunset. Differences in emergence andmove‐ment scores between the three study groups were evident, probably linked with age, species or housing conditions, which were inevitably coupled in our study. We found that 2‐year‐old tuatara in captive conditions emerged less frequently than, but once above ground, moved more than 3‐ and 5‐year‐olds in semi‐captive conditions. Activities in semi‐captive conditions were not correlated with temperature, light or humidity. We conclude that young tuatara may be primarily adapted to nocturnal activity, but thermal restrictions and possible hardwired adaptations to avoid predators and conspecifics may make day‐time movements safer.     

Integrating multiple data sources to assess the distribution and abundance of bottlenose dolphins Tursiops truncatus in Scottish waters

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p42/p44-MAPK and PI3K are sufficient for IL-6 family cytokines/gp130 to signal to hypertrophy and survival in cardiomyocytes in the absence of JAK/STAT activation

The effect of differential signalling by IL-6 and leukaemia inhibitory factor (LIF) which signal by gp130 homodimerisation or LIFRβ/gp130 heterodimerisation on survival and hypertrophy was studied in neonatal rat cardiomyocytes. Both LIF and IL-6 [in the absence of soluble IL-6 receptor (sIL-6Rα)] activated Erk1/2, JNK1/2, p38-MAPK and PI3K signalling peaking at 20 min and induced cytoprotection against simulated ischemia-reperfusion injury which was blocked by the MEK1/2 inhibitor PD98059 but not the p38-MAPK inhibitor SB203580. In the absence of sIL-6R, IL-6 did not induce STAT1/3 phosphorylation, whereas IL-6/sIL-6R and LIF induced STAT1 and STAT3 phosphorylation. Furthermore, IL-6/sIL-6R induced phosphorylation of STAT1 Tyr⁷⁰¹ and STAT3 Tyr⁷⁰⁵ were enhanced by SB203580. IL-6 and pheneylephrine (PE), but not LIF, induced cardiomyocyte iNOS expression and nitric oxide (NO) production. IL-6, LIF and PE induced cardiomyocyte hypertrophy, but with phenotypic differences in ANF and SERCA2 expression and myofilament organisation with IL-6 more resembling PE than LIF. Transfection of cardiomyocytes with full length or truncated chimaeric gp130 cytoplasmic domain/Erythropoietin receptor (EpoR) extracellular domain fusion constructs showed that the membrane proximal Box 1 and Box 2 containing region of gp130 was necessary and sufficient for MAPK and PI3K activation; hypertrophy; SERCA2 expression and iNOS/NO induction in the absence of JAK/STAT activation. In conclusion, IL-6 can signal in cardiomyocytes independent of sIL-6R and STAT1/3 and furthermore, that Erk1/2 and PI3K activation by IL-6 are both necessary and sufficient for induced cardioprotection. In addition, p38-MAPK may act as a negative feedback regulator of JAK/STAT activation in cardiomyocytes.     

Pelagic fish and zooplankton species assemblages in relation to water mass characteristics in the northern Bering and southeast Chukchi seas

This research explores the distributions and community composition of pelagic species in the sub-Arctic and Arctic waters of the northern Bering and central and southern Chukchi seas during September 2007 by linking pelagic zooplankton and fish assemblages to water masses. Juvenile saffron cod (Eleginus gracilis), polar cod (Boreogadus saida), and shorthorn sculpin (Myoxocephalus scorpius) were most abundant in warm, low salinity Alaska Coastal Water (ACW) of the central Chukchi Sea, characterized by low chlorophyll, low nutrients, and small zooplankton taxa. Adult Pacific herring (Clupea pallasii) were more abundant in the less stratified Bering Strait waters and in the colder, saltier Bering Shelf Water of the northern Bering and southern Chukchi seas, characterized by high chlorophyll, high nutrients, and larger zooplankton taxa. Juvenile pink (Oncorhynchus gorbuscha) and chum (O. keta) salmon were most abundant in the less stratified ACW in the central Chukchi Sea and Bering Strait. Abundances of large zooplankton were dominated by copepods (Eucalanus bungii, Calanus glacialis/marshallae, Metridia pacifica) followed by euphausiids (juvenile Thysanoessa raschii and unidentified taxa), whereas small zooplankton were dominated by bivalve larvae and copepods (Centropages abdominalis, Oithona similis, Pseudocalanus sp.). Pelagic community composition was related to environmental factors, with highest correlations between bottom salinity and large zooplankton taxa, and latitude and fish species. These data were collected in a year with strong northward retreat of summer sea ice and therefore provide a baseline for assessing the effects of future climate warming on pelagic ecosystems in sub-Arctic and Arctic regions.