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We find that risk factors associated with mortality differ between species, and that few generalizable patterns exist when bark beetle outbreaks occur in concert with a particularly long, hot drought. We see evidence that both long-term differences in physiology and shorter-term beetle-related selection and variability in defenses influence mortality susceptibility for ponderosa pine, whereas beetle dynamics may play a more prominent role in mortality patterns for white fir and pinyon pine. selleck inhibitor In contrast, incense cedar mortality appears to be attributable to long-term effects of growth suppression. Risk factors that predispose some trees to drought and beetle-related mortality likely reflect species-specific strategies for dealing with these particular disturbance types. The combined influence of beetles and drought necessitates the consideration of multiple, species-specific risk factors to more accurately model forest mortality in the face of similar extreme events more likely under future climates.The crosstalk between the estrogen receptor (ER) and NF-κB signalling pathways has merged in vertebrates and plays a key role in the control of genes involved in inflammation, cell proliferation and apoptosis. However, such crosstalk between the endocrine and immune systems needs to be explored in lower invertebrates. In this study, we identified a 2856-bp homologue of the estrogen receptor from Hong Kong oyster (ChER), containing a 5′ untranslated region (UTR) of 234 bp, a 3′ UTR of 387 bp, and an open reading frame (ORF) of 2235 bp. We observed that overexpression of ChER suppressed ChRel-dependent NF-kappaB (NF-κB) activation in the HEK293T (human embryonic kidney 293T) cell line, and depletion of ChER in vivo resulted in upregulation of two NF-κB-responsive marker genes, namely, TNF-α and IL-17, which confirmed its potential role in controlling NF-κB signalling. Furthermore, an EMSA (electrophoretic mobility shift assay) showed that ChER could negatively regulate the binding of ChRel to NF-κB probe-responsive elements. Serial domain requirement analysis showed that both region C (DNA-binding domain) and region E (ligand-binding domain) of ChER were essential for mediating the crosstalk underlying ChER-dependent NF-κB suppression. In conclusion, we demonstrate for the first time the negative regulatory role of the ER in NF-κB signalling in oysters, strongly indicating the presence of complex crosstalk between the endocrine and immune systems in lower marine molluscs.Moon phases influence the molting process of shrimp, which affect other physiological processes as immune response. This study analyzed some parameters of immune response total hemocytes counts (THC), hemolymph clotting time and superoxide anion (O2-) production, total protein concentration, superoxide dismutase activity, and the presence of Vibrio spp. in Litopenaeus vannamei at different moon phases. The highest percentage of organisms in intermolt stage was observed in the first quarter moon phase (95%). The highest THC was observed at new moon phase, which was significantly different (p 0.05) between different moon phases. The higher (p less then 0.05) mean O2- production value (0.400 ± 0.168 nmol min-1 mL-1) was determined in hepatopancreas at new moon phase. No relationship was observed between O2- and SOD activity, indicating that this antioxidant response was enough to counteract the influence of oxidative stress in L. vannamei at different moon phases.Fish nocardiosis is a widespread chronic granulomatous disease in aquatic environment, which was particularly caused by Nocardia seriolae. The phage shock protein A (PspA) and tellurium resistance protein D (TerD) were identified to be the immunodominant antigens of the wild-type N. seriolae strain ZJ0503 in our previous study. In an attempt to develop effective DNA vaccines against this pathogen, PspA and TerD were used as candidates to ligate with pcDNA3.1-Flag plasmids, respectively. In addition, the abilities of these two DNA vaccines to elicit various immune responses in hybrid snakehead and supply protective efficacy against artificial challenge with N. seriolae were determined in the present study. The results showed that intramuscular injection with pcDNA-PspA and pcDNA-TerD did not exhibit cytotoxic activities in hybrid snakehead via histopathological examination. Besides, hybrid snakehead immunization with pcDNA-PspA and pcDNA-TerD could increase several non-specific immune paraments in serum, including LYZ, POD, ACP, AKP and SOD activities. Meanwhile, the pcDNA-TerD DNA vaccine could induce strongly specific antibody (IgM) titer in hybrid snakehead with a relative percent of survival (RPS) value of 83.14% against N. seriolae, while that of pcDNA-PspA DNA vaccine was displayed comparably low IgM titer with RPS value of 57.83%. Furthermore, quantitative real-time PCR assays presented that the expression of immune-related genes (MHCIα, MHCIIα, CD4, CD8α, IL-1β and TNFα) were up-regulated to various degrees after vaccination with pcDNA-PspA or pcDNA-TerD, indicating that these two DNA vaccines were able to boost humoral and cell-mediated immune responses in hybrid snakehead. Taken together, both the pcDNA-PspA and pcDNA-TerD DNA vaccines were proved to be safe, immunogenic and effective in protecting hybrid snakehead against N. seriolae infection, which can promote the development and application of DNA vaccines to control fish nocardiosis in aquaculture.The Atlantic bluefin tuna (ABFT; Thunnus thynnus) today represents one of the economically most important species for Croatian fisheries industry. Although the most diverse and abundant parasitofauna is usually found in the largest specimens of wild ABFT, the opposite was observed in captivity where parasite populations significantly decline by the end of the farming cycle. Copepod Brachiella thynni, is a skin parasite frequently parasitizing tuna, whose population also decreases in number throughout the rearing process. In order to better understand the immunity mechanisms underlying ABFT reaction to B. thynni infection, we studied expression profiles of immunity related genes; interleukin 1β (il1β), tumour necrosis factors (tnfα1, tnfα2), complement component 4 (c4) and caspase 3 (casp3), in peripheral blood leukocytes (PBLs) during in vitro stimulation by B. thynni protein extracts (i.e. antigens) and in infected tissues at B. thynni parasitation site. Finally, a histopathological analysis of semi-thin and ultra-thin sections of tissues surrounding B.