Specific Induction Research Articles

Immune response to pertussis vaccine in COPD patients

Exacerbation triggered by respiratory infection is an important cause of morbidity and mortality in chronic obstructive pulmonary disease (COPD) patients. Strategies aiming to preventing infection may have significant public health impact. Our previous study demonstrated decreased immunological response to seasonal flu vaccination in COPD patients, questioning the efficiency of other vaccines in this group of patients. We performed a prospective, monocenter, longitudinal study that evaluated the humoral and cellular responses upon pertussis vaccination. We included 13 patients with stable COPD and 8 healthy volunteers. No difference in circulating B and T cell subsets at baseline was noted. Both groups presented similar levels of TFH, plasmablasts and pertussis specific antibodies induction after vaccination. Moreover, monitoring T cell immunity after ex-vivo peptide stimulation revealed equivalent induction of functional and specific CD4+ T cells (IFNγ, TNFα and IL-2-expressing T cells) in both groups. Our results highlight the immunological efficiency of pertussis vaccination in this particularly vulnerable population and challenge the concept that COPD patients are less responsive to all immunization strategies. Healthcare providers should stress the necessity of decennial Tdap booster vaccination in COPD patients.

Human anterior cruciate ligament-derived mesenchymal stem cells for regenerative medicine applications

Background: The anterior cruciate ligament (ACL) has poor healing capabilities and is the most commonly injured knee ligament. Although ACL repair is being highly studied, the current treatment involves reconstructive surgery utilizing autografts or allografts, which have limitations. The use of Mesenchymal Stem Cells (MSCs) as a possible therapeutic option has grown. ACL-derived MSCs are likely to be the best source because studies have shown that target tissue derived stem cells will better differentiate into the target tissue than the stem cells derived from non-target ones. However, the existing literature discusses only the isolation of a mixed population of MSCs. Here we present the isolation, differentiation and characterization of human ACL-derived MSCs according to the International Society for Cellular Therapy (ISCT) criteria.The ACL tissue was enzymatically digested. Separation of MSCs from the crude mixture of cells was then performed by fluorescence activated cell sorting (FACS) analysis. The isolated population were passaged in specific induction medium to differentiate them into adipocyte, osteocytes and chondrocytes. The cells were then further characterized with respect to their growth curve, population doubling time, colony forming ability, anchorage independent growth, and cell surface markers. The cells were finally examined for their tumorigenic potential by cell cycle analysis.Immunoprofiling via FACSs showed an average isolation rate for cells carrying MSCs markers of 5.5%. Cells exhibited spindle-shaped morphology, and immunocytochemistry confirmed the expression of appropriate cell surface markers. The growth curve showed distinct lag and log phase. Over agar assay demonstrated no anchorage independent growth, but clonogenic potential was observed post-culture on plastic Petri dishes. The cells showed a population doubling time of about 1.5 days. Oil Red O, Alizarin Red S, and Alcian Blue staining confirmed adipogenic, osteogenic and chondrogenic differentiation, respectively. Cell cycle analysis displayed more ACL-derived MSCs in G/G phase compared to BMSCs, showing that the isolates were non-tumorigenic. The presence of MSCs within the human ACL was confirmed via ISCT criteria, paving the way for their potential use for future ACL reconstructions. Although BMSCs have been the choice for regenerative purposes, making use of MSCs derived from ACL ligament will cut down the burden of trauma one has to undergo to obtain the Bone Marrow. Moreover, it is more convenient to harvest MSCs from otherwise discarded ACL. Finally, MSCs derived from the target tissue are believed to better differentiate to the ligament tissue than the bone derived MSCs.

Characterization of Bovine Bone Marrow Derived Mesenchymal Stem Cells and Immunostaining of Differentiated Neurospheres

Stem cell differentiation has been a key element for the therapeutical applications for various cases. The novel anti-inflammatory and angiogenic findings and potential applications for both autologous and allogenic studies have emphasized about the usage of mesenchymal stem cells in the clinical trials. The neurosphere differentiation studies and their role for peripheral nerve injuries have gained momentum. Following study emphasized on the isolation of stem cells from bovine bone marrow, their characterization by PCR and their differentiation into mesodermal lineages and into neurospheres under specific induction media. The generated neurospheres were durther investigated for their potential expressions of neuroprogenitor markers Sox2, Nestin and neurofilament protein β-III Tubulin by immunofluorescence staining. The results of following study highlight the use of bone marrow derived mesenchymal stem cells for translational research and regenerative therapy.

Implications for a mindfulness-enhanced positive affect induction: A brief commentary toward acute pain management.

Over the past decade research has increased on dynamics between mindfulness, positive affect, and pain. While there have been studies examining the direct use of positive psychology for pain management, few have examined the use of a specific mindfulness-enhanced positive affect induction (i.e. a singular brief technique engendering mindfulness and strong positive affect) toward acute pain and pain flare management. This topical commentary discusses the need for such a technique toward bolstered gold-standard interventions, related studies, and possible future directions for acute and post-surgical pain management. Future research is encouraged to build from prior research on loving-kindness meditation and examine novel, brief mindfulness-enhanced positive affect inductions for acute pain management.

Characteristics, Recombination Methods, and Applications Progresses of Split-Cas9 System.

CRISPR technology has been used to revolutionize various facets of life sciences because of its potent gene editing capabilities. In particular, CRISPR technology is anticipated to be used to cure congenital disorders, and malignant cancers brought on by gene mutation. In this article, we introduce a Split-Cas9 system, in which Cas9 protein is split into two or more parts and recombined in cells to function specific induction circumstances. Split-Cas9 system can improve the therapeutic index of CRISPR technology by splitting Cas9 proteins into small fragments, thus enhancing their compatibility with virus vectors and precise temporal and spatial control. This article examined the combination mode of Split-Cas9 system, contrasted the differences in its split sites and activity efficiency, and discussed the use and clinical transformation in vivo and in vitro.

Inverse Regulation of Cartilage Neogenesis at Physiologically Relevant Calcium Conditions by Human Articular Chondrocytes and Mesenchymal Stromal Cells.

Elaborate bioreactor cultivation or expensive growth factor supplementation can enhance extracellular matrix production in engineered neocartilage to provide sufficient mechanical resistance. We here investigated whether raising extracellular calcium levels in chondrogenic cultures to physiologically relevant levels would provide a simple and inexpensive alternative to enhance cartilage neogenesis from human articular chondrocytes (AC) or bone marrow-derived mesenchymal stromal cells (BMSC). Interestingly, AC and BMSC-derived chondrocytes showed an opposite response to a calcium increase from 1.8 mM to 8 mM by which glycosaminoglycan (GAG) and collagen type II production were elevated during BMSC chondrogenesis but depressed in AC, leading to two-fold higher GAG/DNA values in BMSC-based neocartilage compared to the AC group. According to control treatments with Mg2+ or sucrose, these effects were specific for CaCl2 rather than divalent cations or osmolarity. Importantly, undesired pro-hypertrophic traits were not stimulated by calcium treatment. Specific induction of PTHrP mRNA and protein by 8.0mM calcium only in AC, along with negative effects of recombinant PTHrP1-34 on cartilage matrix production, suggested that the PTHrP pathway contributed to the detrimental effects in AC-based neocartilage. Altogether, raising extracellular calcium levels was discovered as a novel, simple and inexpensive stimulator for BMSC-based cartilage neogenesis without the need for special bioreactors, whereas such conditions should be avoided for AC.

From basic science to clinical practice: Can cognitive behavioural therapy tasks be augmented with enhanced episodic specificity?

Individuals with depression typically remember their past in a generalised manner, at the cost of retrieving specific event memories. This may impair engagement with cognitive behavioural therapy (CBT) tasks that use concrete episodic information to challenge maladaptive beliefs, potentially limiting their therapeutic benefit. Study 1 demonstrated that an episodic specificity induction increased detail and specificity of autobiographical memory in people with major depression, relative to control conditions (N = 88). We therefore examined whether the induction enhanced the efficacy of CBT tasks that depend on episodic memory – cognitive reappraisal (Study 2, N = 30), evidence gathering (Study 2, N = 30), and planning behavioural experiments (Study 3a, N = 30). Across all three tasks, there were no significant differences in emotion- or belief-change between the specificity and control conditions. Although the induction temporarily enhanced specificity in depressed individuals, it did not significantly augment the efficacy of CBT tasks theorised to benefit from the use of specific mnemonic information.

Evaluating the effects of episodic and semantic memory induction procedures on divergent thinking in younger and older adults.

Evidence suggesting that episodic specificity induction improves divergent thinking performance in younger and older adults has been taken as indicative of the role of declarative memory processes in creativity. A series of studies were carried out to verify the specificity of such findings by investigating the effects of several novel episodic and semantic memory induction procedures on a widely employed measure of divergent creative thinking (the Alternate Uses Task), in comparison to a control induction and a no-induction baseline in both younger and older adults. There was no clear evidence for a specific role played by the induction of episodic or semantic memory processes in facilitating creative thinking across the three experiments, and the effects of the induction procedures (episodic, semantic and control) on divergent thinking were not comparable across age groups. On the other hand, higher levels of creativity were generally associated with older adults (60-80 years). In Experiments 2 and 3, older adults generated a greater number of responses (fluency), more unique responses (average originality, peak originality, creativity ratings) and more varied responses (flexibility) than younger adults (18-30 years). The findings are discussed in relation to the specificity of declarative memory operations and their impact on creative thinking, especially within the context of healthy ageing.

Analysis on the Design and Application of Bisection Illusion in the Shaping of Specific Shape

Bisection illusion is a combination of aesthetics and psychology. This concept is embodied in different degrees in modern clothing, but there is no specific and detailed collation and induction in some of the existing literature. It is also scarce to conduct researches that adopt this concept to a certain style of clothing. This paper deduces a bisection illusions theory that is applicable to all types from the concept of narrow segmentation, summarizes from the internal structure of modern clothing to external decoration, and sorts out a variety of latest forms of bisection illusion on clothing, which is a useful practice. It can be concluded that bisection illusion is a creative design technique that maximizes the power of formal beauty and reshaping. This technique came into being in clothing. It has a relative guiding effect on shaping a specific shape.

Identification of Salmonella Pullorum Factors Affecting Immune Reaction in Macrophages from the Avian Host.

The host-specific Salmonella serovar S. Pullorum (SP) modulates the chicken immune response to a Th2-biased response associated with persistent infection. This is different from the Th1-biased immune response induced by the genetically close serovar, S. Enteritidis (SE). Based on core genome differences between SP and SE, we used three complementary bioinformatics approaches to identify SP genes, which may be important for stimulation of the immune response. Defined mutants were constructed in selected genes, and the infection potential and ability of mutants to stimulate cytokine production in avian derived HD11 macrophages were determined. Deletion of large genomic regions unique to SP did not change infection potential nor immune stimulation significantly. Mutants in genes with conserved single nucleotide polymorphisms (SNPs) between the two serovars in the region 100 bp upstream of the start codon (conserved upstream SNPs [CuSNPs]) such as sseE, osmB, tolQ, a putative immune antigen, and a putative persistent infection factor, exhibited differences in induction of inflammatory cytokines compared to wild-type SP, suggesting a possible role of these CuSNPs in immune regulation. Single nucleotide SP mutants correcting for the CuSNP difference were constructed in the upstream region of sifA and pipA. The SNP corrected pipA mutant expressed pipA at a higher level than the wild-type SP strain, and the mutant differentially caused upregulation of proinflammatory cytokines. It suggests that this CuSNP is important for the suppression of proinflammatory responses. In conclusion, this study has identified putative immune stimulating factors of relevance to the difference in infection dynamics between SP and SE in avian macrophages. IMPORTANCE Salmonella Pullorum is host specific to avian species, where it causes life-threatening infection in young birds. It is unknown why it is host restricted and causes systemic disease, rather than gastroenteritis normally seen with Salmonella. In the present study, we identified genes and single nucleotide polymorphisms (SNPs; relative to the broad-host-range type Salmonella Enteritidis), which affected survival and immune induction in macrophages from hens suggesting a role in development of the host specific infection. Further studies of such genes may enable understanding of which genetic factors determine the development of host specific infection by S. Pullorum. In this study, we developed an in silico approach to predict candidate genes and SNPs for development of the host-specific infection and the specific induction of immunity associated with this infection. This study flow can be used in similar studies in other clades of bacteria.

T-cell specific antibody induction versus corticosteroid induction immunosuppression for liver transplant recipients: a meta-analysis

Corticosteroids remain the mainstay of immunosuppression for liver transplant recipients despite several serious complications including infection, hepatitis C virus (HCV) recurrence, diabetes mellitus (DM), and hypertension. We attempted to compare the safety and efficacy of T-cell specific antibody induction with complete corticosteroid avoidance. We searched MEDLINE, EMBASE, and Cochrane central library. Randomized controlled trials comparing T-cell specific antibody induction with corticosteroid induction immunosuppression were included. Our primary outcome was the incidence of biopsy-proven acute rejection. Eleven trials involving 1683 patients were included. The incidence of acute rejection was not significantly different between the antibody and steroid induction groups (risk ratio [RR] 0.85, 95% confidence interval [CI] 0.72, 1.01, P = 0.06, I2 = 0%). However, T-cell specific antibody induction significantly reduced the risk of cytomegalovirus infection (RR 0.48, 95% CI 0.33, 0.70, P = 0.0002, I2 = 3%), HCV recurrence (RR 0.89, 95% CI 0.80, 0.99, P = 0.03, I2 = 0%), DM (RR 0.41, 95% CI 0.32, 0.54, P < 0.0001, I2 = 0%) and hypertension (RR 0.71, 95% CI 0.55, 0.90, P = 0.005, I2 = 35%). Trial sequential analysis for acute rejection showed that the cumulative z-curve did not cross the Trial sequential boundary and the required information size was not reached. T-cell specific antibody induction compared to corticosteroid induction seems to significantly reduce opportunistic infections including cytomegalovirus infection and HCV recurrence and metabolic complications including DM and hypertension. However, given the insufficient study power, low quality of evidence, and heterogeneous immunosuppressive regimens, our results should be cautiously appreciated.

Mitochondria-targeted derivative of pterostilbene, a dietary phytoestrogen, exhibits superior cancer cell cytotoxicity via mitochondrial superoxide mediated induction of autophagy

Pterostilbene (trans-3,5-dimethoxy-4-hydroxystilbene;PTS), a dimethyl ether analogue of resveratrol, has been shown to possess anti-bacterial, anti-cancer, anti-inflammatory and antioxidant properties. In the present study, we have synthesized a mitochondria targeted derivative of Pterostilbene (M-PTS) with aim to enhance its anti-cancer efficacy. M-PTS was synthesized by substituting the free hydroxyl group of PTS with a propyl linker and Triphenylphosphonium (TPP+, a membrane-permeable lipophilic cation that readily accumulates and penetrates through the mitochondrial membrane). We observed that mitochondrial uptake of M-PTS in A549 cells was higher (∼8.5-fold) as compared to PTS and M-PTS was more potent in killing human lung (A549) and breast (MCF-7) cancer cells as compared to PTS. IC50 of M-PTS was found to be 0.17 µM and 0.76 µM, respectively, while IC50 of PTS was found to be 40.45 µM and 53.15 µM in A549 and MCF-7 cells, respectively. M-PTS was superior in inhibiting the clonogenic potential of A549 and MCF-7 cell and M-PTS induced apoptosis in A549 cells. M-PTS specifically increased both cytosolic ROS and mitochondrial superoxide levels whereas PTS did not have any effect on mitochondrial superoxide. M-PTS treatment led to autophagy induction in cancer cells. M-PTS induced cytotoxicity was attenuated on pre-treatment with mitochondria-targeted antioxidant (mitoTEMPO) as well as inhibitor of autophagy (chloroquine) signifying the involvement of mitochondrial ROS and autophagy in the cytotoxic effects of M-PTS. In conclusion, the superior cytotoxic efficacy of M-PTS via specific induction of mitochondrial superoxide illustrates the application of mitochondria targeted redox-active natural products as potent anti-cancer drugs.

Fault Detection of Induction Motors with Combined Modeling- and Machine-Learning-Based Framework

This paper deals with the early detection of fault conditions in induction motors using a combined model- and machine-learning-based approach with flexible adaptation to individual motors. The method is based on analytical modeling in the form of a multiple coupled circuit model and a feedforward neural network. In addition, the differential evolution algorithm independently identifies the parameters of the motor for the multiple coupled circuit model based on easily obtained measurement data from a healthy state. With the identified parameters, the multiple coupled circuit model is used to perform dynamic simulations of the various fault cases of the specific induction motor. The simulation data set of the stator currents is used to train the neural network for classification of different stator, rotor, mechanical, and voltage supply faults. Finally, the combined method is successfully validated with measured data of faults in an induction motor, proving the transferability of the simulation-trained neural network to a real environment. Neglecting bearing faults, the fault cases from the validation data are classified with an accuracy of 94.81%.

Inductive Type Impedance of Mo/&lt;i&gt;n&lt;/i&gt;-Si Barrier Structures Irradiated with Alpha Particles

In silicon microelectronics, flat metal spirals are formed to create an integrated inductance. However, the maximum specific inductance of such spirals at low frequencies is limited to a value of the order of tens of microhenries per square centimeter. Gyrators, devices based on operational amplifiers with approximately the same specific inductance as spirals, are also used. Despite the fact that such solutions have been introduced into the production of integrated circuits, the task of searching for new elements with high values of specific inductance is relevant. An alternative to coils and gyrators can be the effect of negative differential capacitance (i.e., inductive type impedance), which is observed in barrier structures based on silicon.The purpose of the work is to study the low-frequency impedance of Schottky diodes (Mo/n-Si) containing defects induced by α-particles irradiation and determination of the parameters of these defects by methods of low-frequency impedance spectroscopy and DLTS (Deep Level Transient Spectroscopy).Unpackaged Schottky diodes Mo/n-Si (epitaxial layer of 5.5 μm thickness and resistivity of 1 Ohm∙cm) produced by JSC “Integral” are studied. Inductance measurements were carried out on the as manufactured diodes and on the diodes irradiated with alpha particles (the maximum kinetic energy of an αparticle is 5.147 MeV). The impedance of inductive type of the Schottky diodes at the corresponding DC forward current of 10 µA were measured in the AC frequency range from 20 Hz to 2 MHz. DLTS spectra were used to determine the parameters of radiation-induced defects. It is shown that irradiation of diodes with alpha particles produces three types of radiation-induced defects: A-centers with thermal activation energy of E1 ≈ 190 meV, divacancies with activation energies of E2 ≈ 230 meV and E3 ≈ 410 meV, and Ecenters with activation energy of E4 ≈ 440 meV measured relative to the bottom of c-band of silicon.

Recognition of commensal bacterial peptidoglycans defines Drosophila gut homeostasis and lifespan.

Commensal microbes in animals have a profound impact on tissue homeostasis, stress resistance, and ageing. We previously showed in Drosophila melanogaster that Acetobacter persici is a member of the gut microbiota that promotes ageing and shortens fly lifespan. However, the molecular mechanism by which this specific bacterial species changes lifespan and physiology remains unclear. The difficulty in studying longevity using gnotobiotic flies is the high risk of contamination during ageing. To overcome this technical challenge, we used a bacteria-conditioned diet enriched with bacterial products and cell wall components. Here, we demonstrate that an A. persici-conditioned diet shortens lifespan and increases intestinal stem cell (ISC) proliferation. Feeding adult flies a diet conditioned with A. persici, but not with Lactiplantibacillus plantarum, can decrease lifespan but increase resistance to paraquat or oral infection of Pseudomonas entomophila, indicating that the bacterium alters the trade-off between lifespan and host defence. A transcriptomic analysis using fly intestine revealed that A. persici preferably induces antimicrobial peptides (AMPs), while L. plantarum upregulates amidase peptidoglycan recognition proteins (PGRPs). The specific induction of these Imd target genes by peptidoglycans from two bacterial species is due to the stimulation of the receptor PGRP-LC in the anterior midgut for AMPs or PGRP-LE from the posterior midgut for amidase PGRPs. Heat-killed A. persici also shortens lifespan and increases ISC proliferation via PGRP-LC, but it is not sufficient to alter the stress resistance. Our study emphasizes the significance of peptidoglycan specificity in determining the gut bacterial impact on healthspan. It also unveils the postbiotic effect of specific gut bacterial species, which turns flies into a "live fast, die young" lifestyle.

Changes in the Histology of Walnut (Juglans regia L.) Infected with Phomopsis capsici and Transcriptome and Metabolome Analysis

Phomopsis capsici (P. capsici) causes branch blight of walnuts, which leads to significant economic loss. The molecular mechanism behind the response of walnuts remains unknown. Paraffin sectioning and transcriptome and metabolome analyses were performed to explore the changes in tissue structure, gene expression, and metabolic processes in walnut after infection with P. capsici. We found that P. capsici caused serious damage to xylem vessels during the infestation of walnut branches, destroying the structure and function of the vessels and creating obstacles to the transport of nutrients and water to the branches. The transcriptome results showed that differentially expressed genes (DEGs) were mainly annotated in carbon metabolism and ribosomes. Further metabolome analyses verified the specific induction of carbohydrate and amino acid biosynthesis by P. capsici. Finally, association analysis was performed for DEGs and differentially expressed metabolites (DEMs), which focused on the synthesis and metabolic pathways of amino acids, carbon metabolism, and secondary metabolites and cofactors. Three significant metabolites were identified: succinic semialdehyde acid, fumaric acid, and phosphoenolpyruvic acid. In conclusion, this study provides data reference on the pathogenesis of walnut branch blight and direction for breeding walnut to enhance its disease resistance.

Research advances on identification and mechanism of insect antiaphrodisiac pheromones

<p indent="0mm">Chemical communication in sexual phenomenon of insects through the diverse chemical structures has a high degree of specificity and attractive induction. As an important messenger for insect reproduction, sex pheromones can be divided into sex pheromone to attract mating and antiaphrodisiac pheromone to inhibit mating. Antiaphrodisiac pheromone is a class of volatile substance transferred to the female insects from the male during the mating. The attractiveness of sexual desire by reducing mating females to other male is an important approach to naturally control reproduction and species propagation. This article summarized several types of chemicals for the insect sexual behavior and briefly discussed the recent advances on the mechanism of action. The mechanism of chemical communication is an essential step of understanding the life cycle of insects, providing the scientific foundation of building a better ecological environment through biological control.

Systemic Hypoxemia Induces Cardiomyocyte Hypertrophy and Right Ventricular Specific Induction of Proliferation.

A recent study suggests that systemic hypoxemia in adult male mice can induce cardiac myocytes to proliferate. The goal of the present experiments was to confirm these results, provide new insights on the mechanisms that induce adult cardiomyocyte cell cycle reentry, and to determine if hypoxemia also induces cardiomyocyte proliferation in female mice. EdU-containing mini pumps were implanted in 3-month-old, male and female C57BL/6 mice. Mice were placed in a hypoxia chamber, and the oxygen was lowered by 1% every day for 14 days to reach 7% oxygen. The animals remained in 7% oxygen for 2 weeks before terminal studies. Myocyte proliferation was also studied with a mosaic analysis with double markers mouse model. Hypoxia induced cardiac hypertrophy in both left ventricular (LV) and right ventricular (RV) myocytes, with LV myocytes lengthening and RV myocytes widening and lengthening. Hypoxia induced an increase (0.01±0.01% in normoxia to 0.11±0.09% in hypoxia) in the number of EdU+ RV cardiomyocytes, with no effect on LV myocytes in male C57BL/6 mice. Similar results were observed in female mice. Furthermore, in mosaic analysis with double markers mice, hypoxia induced a significant increase in RV myocyte proliferation (0.03±0.03% in normoxia to 0.32±0.15% in hypoxia of RFP+ myocytes), with no significant change in LV myocyte proliferation. RNA sequencing showed upregulation of mitotic cell cycle genes and a downregulation of Cullin genes, which promote the G1 to S phase transition in hypoxic mice. There was significant proliferation of nonmyocytes and mild cardiac fibrosis in hypoxic mice that did not disrupt cardiac function. Male and female mice exhibited similar gene expression following hypoxia. Systemic hypoxia induces a global hypertrophic stress response that was associated with increased RV proliferation, and while LV myocytes did not show increased proliferation, our results minimally confirm previous reports that hypoxia can induce cardiomyocyte cell cycle activity in vivo.

RNA-seq analysis reveals the effect of the metamorphic cue (juvenile oysters) on the Rapana venosa larvae

As a vital developmental event, metamorphosis controls the population dynamics of most marine invertebrates and affects the breeding of economic shellfish. Rapana venosa is an economically important species in China, but artificial aquaculture has hampered its metamorphosis process. Previous studies have found that juvenile oysters can effectively induce the metamorphosis of R. venosa, but the specific induction mechanism is not clear. Here, we investigated the mechanism underlying the response of R. venosa to juvenile oysters through the RNA-seq analysis. In this study, the gene set responses to metamorphosis cues (juvenile oysters) in R. venosa were identified, and GO and KEGG enrichment analyses were further performed on these gene sets. The results showed that the expression of the prototype of the class of immediate early genes, the transcription factor AP-1, was rapidly and significantly increased, and the molecular chaperone of NOS, HSP90, exhibited lower expression in the M12 group than in the control group. In contrast, the expression of inhibitors of apoptosis (IAPs) was significantly increased upon exposure to juvenile oysters. Additionally, the Wnt signaling pathway and MAPK signaling pathway were enriched in the trend analysis. These pathways may also play critical regulatory roles in the response to juvenile oysters. Taken together, the results show that competent larvae rapidly respond to the inducing effects of oysters via some immediate early genes, such as the transcription factor AP-1, which may further regulate downstream pathways such as the MAPK signaling pathway to cause subsequent changes, including a decrease in HSP90 and an increase in IAPs. These changes together may regulate the metamorphosis of R. venosa. This study provides further evidence that juvenile oysters are the metamorphosis cues of R. venosa, which may enhance our understanding of the metamorphosis mechanism in this marine invertebrate.

Insights into the susceptibility of Pseudomonas putida to industrially relevant aromatic hydrocarbons that it can synthesize from sugars

Pseudomonas putida DOT-T1E is a highly solvent tolerant strain for which many genetic tools have been developed. The strain represents a promising candidate host for the synthesis of aromatic compounds—opening a path towards a green alternative to petrol-derived chemicals. We have engineered this strain to produce phenylalanine, which can then be used as a raw material for the synthesis of styrene via trans-cinnamic acid. To understand the response of this strain to the bioproducts of interest, we have analyzed the in-depth physiological and genetic response of the strain to these compounds. We found that in response to the exposure to the toxic compounds that the strain can produce, the cell launches a multifactorial response to enhance membrane impermeabilization. This process occurs via the activation of a cis to trans isomerase that converts cis unsaturated fatty acids to their corresponding trans isomers. In addition, the bacterial cells initiate a stress response program that involves the synthesis of a number of chaperones and ROS removing enzymes, such as peroxidases and superoxide dismutases. The strain also responds by enhancing the metabolism of glucose through the specific induction of the glucose phosphorylative pathway, Entner-Doudoroff enzymes, Krebs cycle enzymes and Nuo. In step with these changes, the cells induce two efflux pumps to extrude the toxic chemicals. Through analyzing a wide collection of efflux pump mutants, we found that the most relevant pump is TtgGHI, which is controlled by the TtgV regulator.Graphical