Transcranial ultrasound stimulation modulates neural activities during NREM and REM depending on the stimulation phase of slow oscillations and theta waves in the hippocampus.

Modulation of the hippocampal neural activity by low-intensity transcranial ultrasound stimulation depends on the phase of theta rhythm and can also regulate sleep rhythm. However, until now, the modulatory effect of ultrasound stimulation on neural activity in different sleep states depending on the phase of local field potential stimulation in the hippocampus was unclear. To answer this question, closed-loop ultrasound stimulation was applied to in-phase (upstate)/out-of-phase slow oscillations in the hippocampus during non-rapid eye movement sleep, and to the peaks and troughs of theta oscillations in the hippocampus during wake in a mouse model. Local field potential of the hippocampus within 3-h after the ultrasound stimulation during light-on sleep cycle was recorded. We found that (i) under slow-oscillation in-phase stimulation, ultrasound stimulation upregulated the non-rapid eye movement ratio and decreased the wake ratio. Furthermore, it increased the ripple density during non-rapid eye movement and enhanced the coupling of the spindle-ripple during non-rapid eye movement as well as the theta-high gamma phase-amplitude coupling during the REM period. In addition, theta during the REM period showed a more stable oscillation mode. (ii) Under slow-oscillation out-of-phase stimulation, ultrasound stimulation increased the density of ripple during non-rapid eye movement and enhanced the theta-high gamma phase-amplitude coupling strength during REM. Furthermore, theta oscillations during REM were significantly slower and showed higher variability. (iii) Under the phase-locked peak and trough stimulation of theta oscillation, ultrasound stimulation increased the ripple density during non-rapid eye movement, weakened the coupling strength of spindle-ripple during non-rapid eye movement, and enhanced theta-high gamma phase-amplitude coupling during REM. However, theta oscillation mode was not changed significantly during REM. The above results suggest that the regulatory effect of ultrasound stimulation on neural activity in different sleep states depends on the stimulation phases of slow oscillations and theta waves in the hippocampus.

Transcranial ultrasound stimulation at the peak-phase of theta-cycles in the hippocampus improve memory performance.

The present study aimed to investigate the effectiveness of closed-loop transcranial ultrasound stimulation (closed-loop TUS) as a non-invasive, high temporal-spatial resolution method for modulating brain function to enhance memory. For this purpose, we applied closed-loop TUS to the CA1 region of the rat hippocampus for 7 consecutive days at different phases of theta cycles. Following the intervention, we evaluated memory performance through behavioral testing and recorded the neural activity. Our results indicated that closed-loop TUS applied at the peak phase of theta cycles significantly improves the memory performance in rats, as evidenced by behavioral testing. Furthermore, we observed that closed-loop TUS modifies the power and cross-frequency coupling strength of local field potentials (LFPs) during memory task, as well as modulates neuronal activity patterns and synaptic transmission, depending on phase of stimulation relative to theta rhythm. We demonstrated that closed-loop TUS can modulate neural activity and memory performance in a phase-dependent manner. Specifically, we observed that effectiveness of closed-loop TUS in regulating neural activity and memory is dependent on the timing of stimulation in relation to different theta phase. The findings implied that closed-loop TUS may have the capability to alter neural activity and memory performance in a phase-sensitive manner, and suggested that the efficacy of closed-loop TUS in modifying neural activity and memory was contingent on timing of stimulation with respect to the theta rhythm. Moreover, the improvement in memory performance after closed-loop TUS was found to be persistent.

First principles calculation of the ZnV2O6(001) surface terminations: the thermodynamic stability and electronic structure study.

We have investigated the surface structure and relative stability of ZnV2O6(001) using a thermodynamic technique based on density functional theory (DFT). We built Zn-V-O surface phase diagrams of various surface terminations using the obtained surface Gibbs free energy. In this study, we selected nine different surface terminations along the (001) crystal plane to elucidate that the E, G, H, and I terminations (as shown in Table 1) are the most stable configurations. We found that although their stability varies widely, the four terminations on the ZnV2O6(001) surface can be stabilized under specific thermodynamic equilibrium circumstances. Furthermore, we calculated the surface electronic structures of the four surface terminations and found that there are surface states conducive to visible light absorption at the G, H, and I terminations. The different termination structures are significant in improving the range and intensity of light absorption of ZnV2O6 in specific regions. The fact that the work functions fluctuate significantly for different surface terminations suggests that the work function of ZnV2O6 can be changed to increase photocatalytic activity by achieving thermodynamically favored surface terminations under appropriate conditions. The obtained surface phase diagram will further lay a foundation for the study of the ZnV2O6 surface. These results may help to explore the inherent properties of the ZnV2O6 surface and provide useful strategies for future experimental research on ZnV2O6-based photocatalysts.

Characterization of exogenous lactate addition on the growth, photosynthetic performance, and biochemical composition of four bait microalgae strains.

AIMS: To quickly obtain the biomass of bait microalgae with high value-added products, researchers have examined the influence of biochemical and environmental factors on the growth rates and biochemical composition of microalgae. Previous studies have shown that lactate plays an important role in metabolic regulation in Phaeodactylum tricornutum. In this study, we investigated the effect of exogenous lactate on the growth rates, photosynthetic efficiency, and biochemical composition of four commonly used bait microalgae in aquaculture. METHODS AND RESULTS: The optical density of the algal cultures at specific time points, YII, Fv/Fm, and the total lipid, protein, soluble sugar, insoluble sugar, chlorophyll a, and carotenoid content of P. tricornutum, Isochrysis galbana (I. galbana), Chaetoceros muelleri, and Cylindrotheca fusiformis were determined. In I. galbana, the growth rate was enhanced with the addition of lactate, even though higher concentrations of lactate were associated with a decrease in YII and Fv/Fm. In general, the total lipid content of these microalgal strains increased gradually in a concentration-dependent manner over the range of lactate concentrations. In addition, higher concentrations of lactate also induced significant changes in the total soluble and insoluble sugar levels in all microalgal strains. However, chlorophyll a and carotenoid contents increased at lower but decreased at higher concentrations of lactate in all microalgal strains. The total protein content was significantly elevated at all concentrations of lactate in P. tricornutum, whereas there were no significant differences in that of C. fusiformis. CONCLUSIONS: Lactate effective influences in the growth, metabolism, and synthesis of important biochemical components in the four microalgal strains under investigation.

Increasing probability of record-population exposure to high temperature and related health-risks in China.

Combining the comprehensive effects of temperature and humidity, this study applies a heat stress index to project future population exposure to high temperature and related health-risks over China under different climate change scenarios. Results show that the number of high temperature days, population exposure and their related health-risks will increase significantly in the future compared to the reference period (1985-2014), which is mainly caused by the change of >T99p (the wet bulb globe temperature >99th percentile derived from the reference period). The population effect is absolutely dominant in influencing the decrease in exposure to T90-95p (the wet bulb globe temperature is in the range of (90th, 95th]) and T95-99p (the wet bulb globe temperature is in the range of (95th, 99th]), and the climate effect is the most prominent contributor to the upsurge in exposure to > T99p in most areas. An additional 0.1 billion person-days increase in population exposure to T90-95p, T95-99p and >T99p in a given year is associated with the number of deaths by 1002 (95% CI: 570-1434), 2926 (95% CI: 1783-4069) and 2635 (95% CI: 1345-3925), respectively. Compared with the reference period, total exposure to high temperature under the SSP2-4.5 (SSP5-8.5) scenario will increase to 1.92 (2.01) times in the near-term (2021-2050) and 2.16 (2.35) times in the long-term (2071-2100), which will increase the number of people at heat risk by 1.2266 (95% CI: 0.6341-1.8192) [1.3575 (95% CI: 0.6926-2.0223)] and 1.5885 (95% CI: 0.7869-2.3902) [1.8901 (95% CI:0.9230-2.8572)] million, respectively. Significant geographic variations exist in the changes of exposure and related health-risks. The change is greatest in the southwest and south, whereas it is relatively small in the northeast and north. The findings provide several theoretical references for climate change adaptation.

[Modulation of motor responses and neural activities with transcranial ultrasound stimulation based on closed-loop control].

Closed-loop transcranial ultrasound stimulation technology is based on real-time feedback signals, and has the potential for precise regulation of neural activity. In this paper, firstly the local field potential (LFP) and electromyogram (EMG) signals of mice under different intensities of ultrasound stimulation were recorded, then the mathematical model of ultrasound intensity and mouse LFP peak/EMG mean was established offline based on the data, and the closed-loop control system of LFP peak and EMG mean based on PID neural network control algorithm was simulated and built to realize closed-loop control of LFP peak and EMG mean of mice. In addition, using the generalized minimum variance control algorithm, the closed-loop control of theta oscillation power was realized. There was no significant difference between the LFP peak, EMG mean and theta power under closed-loop ultrasound control and the given value, indicating a significant control effect on the LFP peak, EMG mean and theta power of mice. Transcranial ultrasound stimulation based on closed-loop control algorithms provides a direct tool for precise modulation of electrophysiological signals in mice.

Effects of Lactobacillus pentosus combined with Arthrospira platensis on the growth performance, immune response, and intestinal microbiota of Litopenaeus vannamei.

Litopenaeus vannamei is one of the most productive shrimp species in the world. However, shrimp farming is suffering from adverse environmental conditions and disease outbreaks. Typically, Lactobacillus pentosus and Arthrospira platensis are used as substitutes for some antibiotics. In the present study, we assessed the effects of dietary supplements along with living bacteria or cell-free extracts of L. pentosus combined with A. platensis on the growth performance, immune response, intestinal microbiota, and disease resistance of L. vannamei against Vibrio alginolyticus. Shrimp fed L. pentosus live bacteria combined with A. platensis showed the best growth performance and lowest feed conversion rate. The supplementation diet with L. pentosus live bacteria and A. platensis could significantly enhance the trypsin activity in shrimp after the feeding trial. Given the lowest feed conversion rate in shrimp fed L. pentosus live bacteria combined with A. platensis, we reasonably speculated that the decrease in feed conversion rate may be related to the increase in trypsin activity. In addition, dietary cell-free extracts of L. pentosus combined with A. platensis enhanced the expression of immune-related genes after the feeding trial or challenge test. Moreover, results of the bacterial challenge test indicated that the shrimp fed cell-free extracts of L. pentosus combined with A. platensis diet resulted in the highest survival rate, which suggested that cell-free extracts of L. pentosus and A. platensis could improve the disease resistance against V. alginolyticus by up-regulating the expressions of immune-related genes. Dietary L.pentosus or A. platensis, or their combination, reduced the abundance of harmful bacteria, including Proteobacteria in shrimp intestine, which suggested that L. pentosus and A. platensis could improve the growth performance and health of shrimp by regulating the structure of the intestinal microbiota. The findings of this study demonstrated that L. pentosus live bacteria and A. platensis exerted synergistic effects on the growth performance and digestion in shrimp, while cell-free extracts of L. pentosus and A. platensis showed synergistic effects on the immune response and disease resistance of shrimp against V. alginolyticus.

Genetic regulation and fermentation strategy for squalene production in Schizochytrium sp.

Squalene, as an important terpenoid, is extensively used in the medicine and health care fields owing to its functions of anti-oxidation, blood lipid regulation and cancer prevention. The marine microalgae, Schizochytrium sp., which acts as an excellent strain with potential of high squalene production was selected as the starting strain. The overexpressed strain with sqs gene got the reduced biomass and lipid, while the squalene titer was increased by 79.6% ± 4.7% to 12.8 ± 0.2 mg/L. In order to further increase squalene production, the recombinant strain (HS strain) with sqs and hmgr gene co-overexpression was further constructed. The biomass and squalene titer of the HS strain were increased by 13.6% ± 1.2% and 88.8% ± 5.3%, respectively, which indicated the carbon flux of the mevalonate pathway was enhanced for squalene accumulation. Regarding the squalene synthesis is completely coupled with cell growth, fermentation strategy to prolong the logarithmic growth phase was conducive to improve squalene production. Under the condition of optimal composition and concentrated medium, the squalene titer of HS strain was 27.0 ± 1.3 mg/L, which was 2.0 times that of the basal medium condition (13.5 ± 0.4 mg/L). This study which combined the metabolic engineering and fermentation strategy provides a new strategy for squalene production in Schizochytrium sp. KEY POINTS: •The overexpression of sqs and hmgr genes promoted carbon metabolism for squalene. •The optimal and concentrated media can increase squalene yield.

Prevalence of Bacterial Coinfections with Vibrio harveyi in the Industrialized Flow-through Aquaculture Systems in Hainan Province: A Neglected High-Risk Lethal Causative Agent to Hybrid Grouper.

Vibrio harveyi is one of the most serious bacterial pathogens to aquatic animals worldwide. Evidence is mounting that coinfections caused by multiple pathogens are common in nature and can alter the severity of diseases in marine animals. However, bacterial coinfections involving V. harveyi have received little attention in mariculture. In this study, the results of pathogen isolation indicated that bacterial coinfection was a common and overlooked risk for hybrid groupers (♀ Epinephelus polyphekadion × â™‚ E. fuscoguttatus) reared in an industrialized flow-through pattern in Hainan Province. The artificial infection in hybrid groupers revealed that coinfections with V. harveyi strain GDH11385 (a serious lethal causative agent to groupers) and other isolated pathogens resulted in higher mortality (46.67%) than infection with strain GDH11385 alone (33.33%), whereas no mortality was observed in single infection with other pathogens. Furthermore, the intestine, liver and spleen of hybrid groupers are target organs for bacterial coinfections involving V. harveyi. Based on the infection patterns found in this study, we propose that V. harveyi may have a specific spatiotemporal expression pattern of virulence genes when infecting the host. Taken together, bacterial coinfection with V. harveyi is a neglected high-risk lethal causative agent to hybrid groupers in the industrialized flow-through aquaculture systems in Hainan Province.

Cross-habitat distribution pattern of Bacillus communities and their capacities of producing industrial hydrolytic enzymes in Paracel Islands: Habitat-dependent differential contributions of the environment.

Bacillus as a predominant genus of enzyme-producing bacteria presents desirable features to fulfill the vast demand of specific industries, whereas the knowledge of the Bacillus communities and their capacities of producing industrial hydrolytic enzymes across the microhabitats of the Paracel Islands is limited. Herein, a total of 193 culturable Bacillus strains belonging to 19 species were isolated across the microhabitats of seawater, sediment, coral and seagrass, covering 39 stations of the Paracel Islands. Each microhabitat displayed its unique species, while the species of Bacillus paramycoides besides being the dominant species with an abundance of 54.94% also was the only species shared by all microhabitats of the Paracel Islands. Of the Bacillus communities, 97.41% of the isolates exhibited the capacity of producing one-or-more types of enzymes with comparatively higher and broader ranges of enzyme activities, including 163 protease-, 27 cellulase-, 118 alginate lyase-, 140 K-carrageenase- and 158 agarose-producing strains. By the correlation analyses of "Bacillus-environmental factors" and "Enzyme-producing Bacillus-environmental factors", the cross-habitat distribution and enzyme-producing capacity pattern of the Bacillus communities were strongly driven by habitat type, and the environmental factors made habitat-dependent differential contributions to that in the Paracel Islands. It's worth noting that the cellulase-producing strain wasn't detected in seagrass due to its survival strategy to prevent cellulose degradation by inhibiting cellulase-producing bacteria, while coral contained more stable microbial metabolic functions to protect against environmental fluctuations. These findings besides providing large quantities of promising enzyme-producing candidates for specific industrial desires, also facilitate the development and utilization of marine microbial resources and the environmental policy- and/or law-making according to environmental features across the microhabitats of the Paracel Islands.

Online risky behavior and sleep quality among Chinese college students: The chain mediating role of rumination and anxiety.

This study explored the chain mediating effects of rumination and anxiety in the relationship between online risky behavior and sleep quality among Chinese college students. A sample of 1039 Chinese college students (Mage = 19.49, SD = 1.14, 53.32% males) were investigated with Online Risky Behavior Scale (ORBS), Pittsburgh Sleep Quality Index scale (PSQI), Ruminative Responses Scale (RRS) and Self-rating Anxiety Scale (SAS). The results showed that: (1) There is a significant positive correlation among online risky behavior, sleep quality, rumination and anxiety, and (2) Online risky behavior could not directly affect sleep quality, but it can affect sleep quality through the mediation of rumination and anxiety. The chain mediating effects includes three paths: The mediating role of rumination, the mediating role of anxiety, and the chain mediating role of rumination and anxiety after controlling for gender, grade, major, and network usage time. These findings contribute to a deeper understanding of how online risky behavior affects sleep quality and provide important practical guidance for improving sleep quality.

Maternal Mental Health Status and Approaches for Accessing Antenatal Care Information During the COVID-19 Epidemic in China: Cross-Sectional Study.

BACKGROUND: China was the first country in the world to experience a large-scale COVID-19 outbreak. The rapid spread of the disease and enforcement of public health measures has caused distress among vulnerable populations such as pregnant women. With a limited understanding of the novel, emerging infectious disease, pregnant women have sought ways to access timely and trusted health care information. The mental health status of pregnant women during this public health emergency, as well as how they responded to the situation and where and how they obtained antenatal care information, remain to be understood. OBJECTIVE: This study aimed to evaluate the mental health status of pregnant women during the COVID-19 epidemic in China by measuring their perceived stress, anxiety, and depression levels; explore the approaches used by them to access antenatal health care information; and determine their associations with maternal mental health status. METHODS: We conducted a web-based, cross-sectional survey to assess the mental health status of Chinese pregnant women by using the validated, Chinese version of Perceived Stress Scale, Self-Rating Anxiety Scale, and Edinburgh Depression Scale. We also collected information on the various approaches these women used to access antenatal care information during the early stage of the COVID-19 epidemic, from February 5 to 28, 2020. RESULTS: A total of 1873 pregnant women from 22 provinces or regions of China participated in the survey. The prevalence of perceived stress, anxiety, and depression among these participants was 89.1% (1668/1873; 95% CI 87.6%, 90.4%), 18.1% (339/1873; 95% CI 16.4%, 19.9%), and 45.9% (859/1873; 95% CI 43.6%, 48.1%), respectively. Hospitals' official accounts on the Chinese social media platforms WeChat and Weibo were the most popular channels among these pregnant women to obtain antenatal care information during the COVID-19 outbreak. Access to antenatal care information via the hospitals' official social media accounts was found to be associated with a significantly lower risk of perceived stress (adjusted odds ratio [aOR] 0.46, 95% CI 0.30-0.72; P=.001), anxiety (aOR 0.53, 95% CI 0.41-0.68; P<.001), and depression (aOR 0.73, 95% CI 0.59-0.91; P=.005). Access to health care information via hospital hotlines or SMS was found to be significantly associated with a lower risk of anxiety only (OR 0.77, 95% CI 0.60-0.98; P=.04). CONCLUSIONS: During the COVID-19 outbreak in China, pregnant women experienced high levels of perceived stress, anxiety, and depression. During such public health emergencies, mental health care services should be strengthened to reassure and support pregnant women. Specific information targeted at pregnant women, including information on how to cope in an emergency or major disease outbreak, developed and disseminated by health care institutions via social media platforms could be an effective way to mitigate mental health challenges and ensure epidemic preparedness and response in the future.

Analysis of the expression and potential molecular mechanism of interleukin-1 receptor antagonist (IL1RN) in papillary thyroid cancer via bioinformatics methods.

BACKGROUND: Interleukin-1 receptor antagonist (IL1RN) has been reported as a biomarker of many cancers. However, the biological function of IL1RN in papillary thyroid carcinoma (PTC) remains undetermined. METHODS: We obtained IL1RN expression data from The Cancer Genome Atlas (TCGA) database. Enrichment analysis of coexpressed genes and IL1RN methylation analysis were performed via LinkedOmics. The correlations between IL1RN and immune infiltrates were investigated via ESTIMATE, TIMER and TISIDB. We analyzed the association of IL1RN expression with pancancer overall survival (OS) via Gene Expression Profiling Interactive Analysis (GEPIA). RESULTS: IL1RN showed higher expression levels and lower methylation levels in PTC tissues than in normal tissues. Higher IL1RN expression was significantly associated with shorter progression-free survival (PFS), advanced tumor stage, tumor metastasis, increased incidence of BRAF mutations, and decreased incidence of N-RAS and H-RAS mutations. Genes coexpressed with IL1RN participate primarily in immune-related pathways. IL1RN expression positively correlated with immune infiltration, tumor progression and poor OS for all cancers. CONCLUSIONS: IL1RN is a good prognostic and diagnostic biomarker for PTC. IL1RN may promote thyroid cancer progression through immune-related pathways. Methylation may act as an upstream regulator of IL1RN expression and biological function. Additionally, IL1RN was shown to have broad prognostic value in a pancancer cohort.

Construction and analysis of the immune effect of Vibrio harveyi subunit vaccine and DNA vaccine encoding TssJ antigen.

Vibrio harveyi, a severe pathogen infects different kinds of sea animals, causes huge economic loss in aquaculture industry. In order to control the Vibriosis disease caused mainly by V. harveyi and other Vibrio spp., the best solution lies in developing corresponding efficient vaccines. In this study, we have cloned and analysed a putative antigen TssJ from the T6SS of V. harveyi, which has the potential as a vaccine against infection. The sequence analysis and western blotting experiments indicated that TssJ anchored in outer membrane and there were several antigenic determinants existed on its extracellular region. Two forms of universal vaccines, subunit vaccine and DNA vaccine, were developed based on TssJ and applied in Trachinotus ovatus. The results showed that both of the two vaccines could generate a moderate protection in fish against V. harveyi. The relative percentage survival (RPS) of subunit vaccine and DNA vaccine were 52.39% and 69.11%, respectively. Immunological analysis showed both subunit vaccine and DNA vaccine enhanced acid phosphatase, alkaline phosphatase, superoxide dismutase, and lysozyme activities. Specific serum antibodies against TssJ in the fish vaccinated with subunit vaccine was much higher than that in the DNA vaccine group. Several immune-related genes, i.e., IL10, C3, MHC Iα, MHC IIα, and IgM, were induced both by the two forms of vaccines. TNFα and Mx were only upregulated in the DNA vaccine group. However, the induction levels of these genes induced by DNA vaccine were higher than subunit vaccine. All these findings suggested that TssJ from V. harveyi had a potential application value in vaccine industry.

Toxicity of perfluorooctane sulfonate on Phanerochaete chrysosporium: Growth, pollutant degradation and transcriptomics.

As a persistent organic pollutant listed in the Stockholm Convention, perfluorooctane sulfonate (PFOS) is extremely refractory to degradation under ambient conditions. Its potential ecotoxicity has aroused great concerns and research interests. However, little is known about the toxicity of PFOS on fungus. In this study, the white rot fungus Phanerochaete chrysosporium (P. chrysosporium) was adopted to assess the toxicity of PFOS in liquid culture. The addition of 100 mg/L PFOS potassium salt significantly decreased the fungal biomass by up to 76.4% comparing with un-amended control during the incubation period. The hyphostroma of P. chrysosporium was wizened and its cell membrane was thickened, while its vesicle structure was increased, based on the observation with scanning electron microscope (SEM) and transmission electron microscope (TEM). Nevertheless, the PFOS dosage of below 100 mg/L did not show a considerable damage to the growth of P. chrysosporium. The degradation of malachite green (MG) and 2,4-dichlorophenol (2,4-DCP) by P. chrysosporium was negatively affected by PFOS. At the initial dosage of 100 mg/L PFOS, the decolorization efficiency of MG and the degradation efficiency of 2,4-DCP decreased by 37% and 20%, respectively. This might be attributed to the inhibition of PFOS on MnP and LiP activities. The activities of MnP and LiP decreased by 20.6% and 43.4%, respectively. At a high dosage PFOS (100 mg/L), P. chrysosporium could show a high adsorption of MG but lose its pollutant degradation ability. Transcriptome analysis indicated that PFOS contamination could lead to the change of gene expression in the studied white rot fungus, and the genes regulating membrane structure, cell redox process, and cell transport, synthesis and metabolism were impacted. Membrane damage and oxidative damage were the two main mechanisms of PFOS' toxicity to P. chrysosporium.

Enantiomeric Polyketides from the Starfish-Derived Symbiotic Fungus Penicillium sp. GGF16-1-2.

One new racemic mixture, penicilliode A (1) and four pairs of enantiomeric polyketides, penicilliode B and C (2 and 3) and coniochaetone B and C (4 and 5), were obtained from the starfish-derived symbiotic fungus Penicillium sp. GGF16-1-2. Interestingly, the strain GGF16-1-2 can produce enantiomers. The absolute configuration of 1 was determined by X-ray diffraction (XRD) analysis, and the absolute configurations of 2-4 were determined by the optical rotation (OR) values and electronic circular dichroism (ECD) calculations. Compounds 1-5 were firstly isolated from the marine-derived fungus Penicillium as racemates, and 2-5 were separated by HPLC with a chiral stationary phase. All the compounds were evaluated for their antibacterial, cytotoxic and inhibitory activities against PDE4D2.

Transcriptome analysis provides insights into the immune responsive pathways and genes in the head kidney of tiger grouper (Epinephelus fuscoguttatus) fed with Spatholobus suberectus, Phellodendron amurense, or Eclipta prostrata.

The tiger grouper, Epinephelus fuscoguttatus, is an economically important fish in Southeast Asia but has been plagued by several diseases. Spatholobus suberectus (S), Phellodendron amurense (P), and Eclipta prostrate (E) are three commonly used Chinese medicinal herbs. Although previous pharmacological and clinical studies indicated that S, P, and E possess a variety of beneficial functions in mammals, little is known about their functions in farmed fish and the underlying molecular mechanism of their actions. Challenge tests in this study showed that after 14 days of diet supplement, all these herbs could effectively enhance the disease resistance of E. fuscoguttatus against Vibrio harveyi. However, the non-specific immune parameters of the herb-supplemented groups were not significantly different from the control group. To further explore the molecular mechanism of herbal immune-regulating effects on E. fuscoguttatus, transcriptome sequencing and RNA-Seq technique were applied on E. fuscoguttatus kidney. De novo transcriptome assembly of E. fuscoguttatus kidney yield 80,014 unigenes, among which, 44,901 (56.12%) were annotated with at least one of the public databases (Nr, Nt, Swiss-Prot, KEGG, COG, GO). Among these, 22,738, 11,700 and 27,457 unigenes were assigned to 57, 25 and 258 categories of GO, COG and KEGG databases, respectively. Using Solexa/Illumina's DGE platform, a total of 231, 186 and 144 putative differentially expressed genes (DEGs) were detected in P, E and S group compared with the control group. GO analysis indicated that in P and E, down-regulated DEGs were dominant in almost every GO term; whereas in S, up-regulated DEGs were more dominant. KEGG pathway analysis revealed that putative DEGs in all three herb groups were obviously enriched in the pathways related to infective diseases and immune system. We also identified a number of immune relative genes and pathways (TLR5, IL8 and MAPK pathway, for instance) associated with P, E and S's regulatory effects on E. fuscoguttatus. This study will enrich the E. fuscoguttatus transcriptome database, contribute to a better understanding of the molecular mechanisms associated with the immunoregulatory activities of Chinese medicinal herbs on teleost and provide valuable information on the prevention of grouper Vibrio diseases using Chinese medicinal herbs.

Effects of dietary administration of Lactococcus lactis HNL12 on growth, innate immune response, and disease resistance of humpback grouper (Cromileptes altivelis).

Lactic acid bacteria are a common group of probiotics that have been widely studied and used in aquaculture. In the present study, we isolated Lactococcus lactis HNL12 from the gut of wild humpback grouper (Cromileptes altivelis) and explored its probiotic properties. For this purpose, L. lactis HNL12 was added to the commercial fish feed. The results showed that HNL12 had high auto-aggregation ability and strong tolerance to simulated gastrointestinal stress. When C. altivelis consumed a diet containing 0 (control), 106, 108, or 1010 CFU/g HNL12 for four weeks, all of the groupers fed a diet with HNL12 had significantly increased percent weight gain (PWG), especially those fed with 108 CFU/g, which had a PWG of 231.45%. Compared to the control, fish fed with L. lactis HNL12 exhibited significantly increased survival rates following injection with Vibrio harveyi after one month. Immunological analysis showed that C. altivelis fed with HNL12 had (i) enhanced respiratory burst activity of head kidney macrophages, superoxide dismutase, acid phosphatase, and lysozyme activities of serum; (ii) an improved survival rate from 36% to 70%; and (iii) upregulated expression of a broad spectrum of immunity. Meanwhile, de novo transcriptome assembly yielded 89,314 unigenes, which were annotated by at least one of the reference databases (Nr, Swiss-Prot, GO, COG and KEGG). A total of 307 genes showed significantly different expression between the groups fed with or without added HNL12. GO and KEGG enrichment analyses of the significantly different expression gene categories and pathways were related to infectious diseases, antigen processing and presentation, and other immune system responses. These results indicate that L. lactis HNL12 is effective for enhancing the growth, immunity, and disease resistance of C. altivelis; this study also provides insight into the use of probiotics for commercial applications.

Vibrio alginolyticus 16S-23S intergenic spacer region analysis, and PCR assay for identification of coral pathogenic strain XSBZ03.

Porites andrewsi white syndrome (PAWS), caused by Vibrio alginolyticus strains XSBZ03 and XSBZ14, poses a serious threat to corals in the South China Sea. To obtain a specific target against which to develop a rapid PCR detection method for the coral pathogenic strain XSBZ03, the 16S-23S rRNA gene intergenic spacer (IGS) region of 4 strains of V. alginolyticus, including the XSBZ03 and XSBZ14 strains, was amplified, sequenced and analyzed. Six types of IGS were found: IGS0, IGSG, IGSIA, IGSAG, IGSGLV, and IGSGLAV. IGS0, IGSG, IGSIA, IGSAG and IGSGLV appeared to be the most prevalent forms in the 4 strains and the percentage identity range within each type was 91.4-100%, 89.3-98.5%, 83.0-99.8%, 91.5-95.6%, and 88.7-99.3%, respectively. IGSGLAV was found only in the HN08155 strain, a causative agent of fish disease. IGSGLAV, IGSGLV and IGSAG are reported here for the first time in V. alginolyticus. An IGS sequence specific to the XSBZ03 strain was identified following alignment of the homologous IGSs, and used to design strain-specific primers for its rapid identification by PCR. The results from PCR analysis suggest that the method is a rapid, practical, and reliable tool for the identification of the XSBZ03 strain in samples of isolated bacteria, as well as seawater and coral samples spiked with the bacterial strain. This is the first report of a rapid diagnostic assay for a causative agent of PAWS, based on PCR detection of a coral pathogen at the strain level. After applying this assay in coral transplantation, the survival rates of transplanted corals were significantly increased. This diagnostic assay should aid with both the elucidation of the cause of the disease, and transplantation of PAWS-free P. andrewsi in the South China Sea.

Identification, polymorphism and expression of MHC class Iα in golden pompano, Trachinotus ovatus.

The classical major histocompatibility complex class I (MHC I) plays a vital role in the immune system. In this study, we cloned and identified golden pompano (Trachinotus ovatus) MHC Iα (Trov-MHC Iα), which encodes 351 amino acid residues including a leader peptide, α1, α2, α3 domain, a transmembrane region and a cytoplasmic domain. Twenty six different sequences, which encoded various numbers of amino acid residues ranging from 348 to 354, were obtained from 12 individuals. Highly genetic polymorphism was found in the Trov-MHC Iα, especially in the α1 and α2 domains. Meanwhile, in the α1 and α2 domains, 21 positive selected positions were revealed by site models, indicating the diversity of Trov-MHC Iα may be mainly generated by positive selection. Moreover, quantitative real-time reverse transcription PCR and western blotting analyses demonstrated that Trov-MHC Iα was ubiquitously expressed in the nine tested tissues and more highly expressed in intestine, head kidney, gill, and spleen. In the head kidney and spleen, Trov-MHC Iα was significantly upregulated under LPS or poly I:C stimulation. The results of this study provide valuable insight into molecular polymorphism, evolutionary mechanism, expression and function of MHC Iα in the immune system of golden pompano.