Potential transceptor AtNRT1.13 modulates shoot architecture and flowering time in a nitrate-dependent manner.

Compared with root development regulated by external nutrients, less is known about how internal nutrients are monitored to control plasticity of shoot development. In this study, we characterize an Arabidopsis thaliana transceptor, NRT1.13 (NPF4.4), of the NRT1/PTR/NPF family. Different from most NRT1 transporters, NRT1.13 does not have the conserved proline residue between transmembrane domains 10 and 11; an essential residue for nitrate transport activity in CHL1/NRT1.1/NPF6.3. As expected, when expressed in oocytes, NRT1.13 showed no nitrate transport activity. However, when Ser 487 at the corresponding position was converted back to proline, NRT1.13 S487P regained nitrate uptake activity, suggesting that wild-type NRT1.13 cannot transport nitrate but can bind it. Subcellular localization and ß-glucuronidase reporter analyses indicated that NRT1.13 is a plasma membrane protein expressed at the parenchyma cells next to xylem in the petioles and the stem nodes. When plants were grown with a normal concentration of nitrate, nrt1.13 showed no severe growth phenotype. However, when grown under low-nitrate conditions, nrt1.13 showed delayed flowering, increased node number, retarded branch outgrowth, and reduced lateral nitrate allocation to nodes. Our results suggest that NRT1.13 is required for low-nitrate acclimation and that internal nitrate is monitored near the xylem by NRT1.13 to regulate shoot architecture and flowering time.

Fabrication of Polymer/Cholesteric Liquid Crystal Films and Fibers Using the Nonsolvent and Phase Separation Method.

In recent years, liquid crystal materials have drawn great interest because of their wide range of applications. Among various thermochromic materials, cholesteric liquid crystalline (CLC) materials have been well studied and reported. CLC materials have the advantages of ready manipulation and multiple color transitions. For the further development of smart clothing and wearable electronics, however, the incorporation of CLC materials into polymers still remains challenging. The difficulties lie in the prevention of leakage of CLC and retention of the cholesteric liquid crystalline phase. In this work, we demonstrate a versatile nonsolvent and phase separation method using polar solvents to incorporate CLC microspheres into polymer matrix. Poly(vinyl alcohol) (PVA), a water-soluble polymer, is chosen as the polymer because of its high transparency and ease to handle. Using spin-coating and wet spinning techniques, PVA/CLC films and fibers can be fabricated. The formation of CLC microspheres in the polymer matrix is characterized through optical and polarized microscopy. Compared with the CLC films, the PVA/CLC composites demonstrate superior thermal stability. Moreover, both PVA/CLC films and fibers exhibit good color stability from the electrical tests. This work provides an effective strategy to prepare polymer/CLC composites, paving a wide avenue toward applications in smart textiles, display technologies, and medical devices.

Analysis of Differences in Neonatal Sepsis Caused by Streptococcus Agalactiae and Escherichia Coli.

BACKGROUND: Streptococcus agalactiae (GBS) and Escherichia coli (E. coli) are the main pathogenic bacteria in neonatal sepsis. Therefore, the clinical characteristics, nonspecific indicators, and drug susceptibilities of these two bacteria were studied. METHODS: In total, 81 and 80 children with sepsis caused by GBS and E. coli infection, respectively, admitted to the neonatal department of our hospital between May 2012 and July 2023, were selected, and the clinical characteris-tics of the two groups were analyzed. Nonspecific indicators and drug sensitivity test results were analyzed retrospectively. RESULTS: Birth weight, tachypnea, groan, tachycardia or bradycardia, and the incidence of complications, such as pneumonia, respiratory failure, and purulent meningitis, were higher in the GBS group than in the E. coli group. The children were born prematurely, and the mother had a premature rupture of membranes. The incidence of jaundice, abdominal distension, atypical clinical manifestations, and complications of necrotizing enterocolitis was lower than of the E. coli group, and the differences were statistically significant (p < 0.05). The WBC, NE#, NE#/LY#, hs-CRP, and PCT of the GBS group were higher than those of the E. coli group, whereas the MPV, D-D, and FDP levels were lower than those in the E. coli group. The differences were all statistically significant (p < 0.05). The 81-bead GBS had high resistance rates against tetracycline (95%), erythromycin (48.8%), and clindamycin (40%), and no strains resistant to vancomycin, linezolid, penicillin, or ampicillin appeared, whereas 80 strains of E. coli were more resistant to penicillin and third-generation cephalosporins, with the higher resistance rates to ampicillin (68.30%), trimethoprim/sulfamethoxazole (53.6%), and ciprofloxacin (42.90%). Resistance rates to carbapenems and aminoglycosides were extremely low. CONCLUSIONS: Both GBS and E. coli neonatal sepsis have specific clinical characteristics, especially in terms of clinical manifestations, complications, non-specific indicators, and drug resistance. Early identification is important for clinical diagnosis and treatment.

A Mitochondria-Targeted Photosensitizer for Combined Pyroptosis and Apoptosis with NIR-II Fluorescence/Photoacoustic Imaging-Guided Phototherapy.

Overcoming tumor apoptosis resistance is a major challenge in enhancing cancer therapy. Pyroptosis, a lytic form of programmed cell death (PCD) involving inflammasomes, Gasdermin family proteins, and cysteine proteases, offers potential in cancer treatment. While photodynamic therapy (PDT) can induce pyroptosis by generating reactive oxygen species (ROS) through the activation of photosensitizers (PSs), many PSs lack specific subcellular targets and are limited to the first near-infrared window, potentially reducing treatment effectiveness. Therefore, developing effective, deep-penetrating, organelle-targeted pyroptosis-mediated phototherapy is essential for cancer treatment strategies. Here, we synthesized four molecules with varying benzene ring numbers in thiopyrylium structures to preliminarily explore their photodynamic properties. The near-infrared-II (NIR-II) PS Z1, with a higher benzene ring count, exhibited superior ROS generation and mitochondria-targeting abilities, and a large Stokes shift. Through nano-precipitation method, Z1 nanoparticles (NPs) also demonstrated high ROS generation (especially type-I ROS) upon 808 nm laser irradiation, leading to efficient mitochondria dysfunction and combined pyroptosis and apoptosis. Moreover, they exhibited exceptional tumor-targeting ability via NIR-II fluorescence imaging (NIR-II FI) and photoacoustic imaging (PAI). Furthermore, Z1 NPs-mediated phototherapy effectively inhibited tumor growth with minimal adverse effects. Our findings offer a promising strategy for cancer therapy, warranting further preclinical investigations in PDT.

Long-term use and risk of major adverse cardiac events: Comparing enzalutamide and abiraterone in chemotherapy-naïve patients with metastatic castration-resistant prostate cancer.

This is a retrospective cohort study by analyzing a multi-institutional electronic medical records database in Taiwan to compare long-term effectiveness and risk of major adverse cardiac events (MACE) in chemotherapy-naïve metastatic castration-resistant prostate cancer (mCRPC) patients treated with enzalutamide (ENZ) or abiraterone (AA). Patients aged 20 years and older and newly receiving androgen receptor targeted therapies ENZ or AA from September 2016 to December 2019 were included. We followed patients from initiation of therapies to the occurrence of outcomes (prostate-specific antigen (PSA) response rate, PSA progression free survival (PFS), overall survival (OS), and MACE), death, the last clinical visit, or December 31, 2020. We performed multivariable Cox proportional hazard models to compare ENZ and AA groups for the measured outcomes. A total of 363 patients treated with either ENZ (n = 157) or AA (n = 206) were identified. The analysis found a significantly higher proportion of patients with a PSA response rate higher than 50% among those receiving ENZ than among those receiving AA (ENZ vs AA: 75.80% vs 63.59%, P = .01). However, there was no significant difference in PSA PFS (adjusted hazard ratio: 0.86; 95% CI 0.63-1.17) and OS (0.68: 0.41-1.14) between the use of ENZ and AA in chemotherapy-naïve mCRPC patients. Regarding the cardiovascular (CV) safety outcome, there was a significantly lower risk of MACE in patients receiving ENZ, compared to patients receiving AA (0.20: 0.07-0.55). The findings suggest that enzalutamide may be more efficacious for PSA response and suitable for chemotherapy-naïve mCRPC patients with high CV risk profile.

Formation of monodomain polymer-stabilized blue phase liquid crystals using surface acoustic waves.

This work uses surface acoustic waves (SAWs) that are generated by a piezoelectric substrate containing an interdigital transducer (IDT) to which a low voltage of 2 mV was applied at a frequency of 1 kHz to fabricate a polymer-stabilized blue phase liquid crystal (PS-BPLC) layer. The PS-BPLC layer has a more uniform optical microscope (OM) image at a voltage of 2 mV than at zero voltage, and its reflective spectrum exhibits a smaller full width at half maximum (FWHM) at the former than at the latter. The uniform OM image and small FWHM reveal that the lattices in the PS-BPLC layer have monodomain structure. The monodomain PS-BPLC layer is formed because the SAWs cause longitudinal and transverse vibrations of the PS-BPLC lattices in the vertical plane along their traveling direction. The proposed method for fabricating the monodomain PS-BPLC layer using the SAWs has potential for the development of reflective optical devices that consume low power during their fabrication.

Identification of Rab7 as an autophagy marker: potential therapeutic approaches and the effect of Qi Teng Xiao Zhuo granule in chronic glomerulonephritis.

CONTEXT: Qi Teng Xiao Zhuo granule (QTXZG) is a traditional Chinese medicine (TCM) used for therapeutic effects on chronic glomerulonephritis (CGN). However, the underlying mechanism remains unclear. OBJECTIVE: To investigate the molecular mechanism of QTXZG on CGN by proteomics. MATERIALS AND METHODS: The CGN model was induced in Sprague-Dawley rats by injecting adriamycin (3.5 mg/kg, Day 1; 3.0 mg/kg, Day 14) twice through the tail vein. Urine samples were collected on the 21st day; and the rats divided randomly into control, adriamycin, QTXZG administration groups. Rats in the QTXZG group received QTXZG (10.8 g/kg); control and adriamycin groups were given physiological saline once per day for 30 days. Proteomics was applied to identify the candidate proteins combined with autophagy database and verified by immunofluorescence (IF) and western blots (WB). RESULTS: 278 differentially expressed proteins (DEPs) were identified based on proteomics and Rab7 was screened as an autophagy protein biomarker. In vitro cell experiments, we found that QTXZG (20%, IC50 = 23.47%) could decrease the expression of NLRP3, Caspase-1, IL-18, IL-1ß, while increasing the expression of Pink1, Parkin, Rab7, Podocalyxin. The cell apoptosis rate increased from 6.68 ± 0.07 to 11.03 ± 0.36%. Overexpression of Rab7 resulted in an increase in autophagy relevant protein expression. DISCUSSION AND CONCLUSION: TCM CGN-regulating herbs (QTXZG) can exert therapeutic effects by affecting the Rab7/Pink1/Parkin pathway to promote mitochondrial autophagy. New breakthroughs in targeted Rab7 may eventually enable such applications.

Progress on Z genome biosynthetic pathway of bacteriophage.

There are abundant base modifications in bacteriophages' genomes, mainly for avoiding the digestion of host endonucleases. More than 40 years ago, researchers discovered that 2-amino-adenine (Z) completely replaced adenine (A) and forms a complementary pairing with three hydrogen bonds with thymine (T) in the DNA of cyanophage S-2L, forming a distinct "Z-genome". In recent years, researchers have discovered and validated the biosynthetic pathway of Z-genome in various bacteriophages, constituting a multi-enzyme system. This system includes the phage-encoded enzymes deoxy-2'-aminoadenylosuccinate synthetase (PurZ), deoxyadenosine triphosphate hydrolase (dATPase/DatZ), deoxyadenosine/deoxyguanosine triphosphate pyrophosphatase (DUF550/MazZ) and DNA polymerase (DpoZ). In this review, we provide a concise overview of the historical discovery on diversely modified nucleosides in bacteriophages, then we comprehensively summarize the research progress on multiple enzymes involved in the Z-genome biosynthetic pathway. Finally, the potential applications of the Z-genome and the enzymes in its biosynthetic pathway are discussed in order to provide reference for research in this field.

Efficacy of epidural analgesia for intractable cancer pain: A systematic review.

BACKGROUND: Epidural analgesia is a common technique for managing perioperative and obstetric pain. Patients with cancer who cannot tolerate opioids or not responding to conventional treatment may benefit from epidural analgesia. Therefore, this systematic review aimed to analyze the efficacy and safety of epidural analgesia in patients with intractable cancer pain. METHODS: We searched PubMed, Embase, and the Cochrane Central Register of Controlled Trials to identify studies on patients with cancer who received epidural analgesia. We assessed the quality of all included studies using the risk-of-bias tool or Newcastle-Ottawa scale. The primary outcome was pain relief after epidural analgesia, and the secondary outcome was quality of life, analgesic consumption, and adverse events. The studies were grouped based on the medications used for epidural analgesia. A descriptive synthesis was performed following the Synthesis Without Meta-analysis reporting guideline. RESULTS: Our systematic review included nine randomized controlled trials (n = 340) and 15 observational studies (n = 926). Two randomized controlled trials suggested that epidural opioids were not superior to systemic opioids in relieving pain. Epidural opioids combined with local anesthetics or adjuvants, including calcitonin, clonidine, ketamine, neostigmine, methadone, and dexamethasone, offered better analgesic effects. No significant difference in pain relief between an intermittent bolus and a continuous infusion of epidural morphine was observed. Epidural opioids had more analgesic effects on nociceptive pain than neuropathic pain. The methods used to evaluate the quality of life and the corresponding results were heterogeneous among studies. Six observational studies demonstrated that some patients could have decreased opioid consumption after epidural analgesia. Adverse events, including complications and drug-related side effects, were reported in 23 studies. Five serious complications, such as epidural abscess and hematoma, required surgical management. The heterogeneity and methodological limitations of the studies hindered meta-analysis and evidence-level determination. CONCLUSION: Coadministration of epidural opioids, local anesthetics, and adjuvants may provide better pain relief for intractable cancer pain. However, we must assess the patients to ensure that the benefits outweigh the risks before epidural analgesia. Therefore, further high-quality studies are required.

Concise total syntheses of two flavans and structure revision assisted by quantum NMR calculations.

A two-step protecting-group-free protocol for the synthesis of 3'-hydroxy-5,7-dimethoxy-4-O-2'-cycloflavan (1) and concise total synthesis of 4'-hydroxy-5,7-dimethoxy-4-O-2'-cycloflavan (8) enabled by a PTSA triggered bioinspired olefin isomerization/hemiacetalization/dehydration/[3 + 3]-type cycloaddition cascade reaction are reported. The successful synthesis of cycloflavan 8 along with GIAO 13C NMR calculations of flavan-4-ol 9 and cycloflavan 8 indicated the misassignment of the flavonoid isolated previously and realized the revision of its actual structure.

One-pot catalyst-free synthesis of benzopyrroxazine derivatives by a mutually activated sequential annulation process.

A one-pot catalyst-free reaction of o-hydroxyaryl azomethine ylides, vinyl pyridines and paraformaldehyde for the synthesis of benzopyrroxazines is reported, which offers a straightforward and atom-economical procedure for the preparation of benzopyrroxazine derivatives in moderate to excellent yields under mild conditions. A self-catalyzed [3 + 2] annulation through a mutual activation method and a sequential non-catalyzed [5 + 1] annulation process contribute to this strategy. The corresponding control experiments have been conducted to reveal the mechanism of this reaction.

Blockade of SK4 channels suppresses atrial fibrillation by attenuating atrial fibrosis in canines with prolonged atrial pacing.

Background: We previously found that intermediate conductance Ca2+-activated K+ channel (SK4) might be an important target in atrial fibrillation (AF). Objective: To investigate the role of SK4 in AF maintenance. Methods: Twenty beagles were randomly assigned to the sham group (n=6), pacing group (n=7), and pacing+TRAM-34 group (n=7). Rapid atrial pacing continued for 7 days in the pacing and TRAM-34 groups. During the pacing, the TRAM-34 group received TRAM-34 intravenous injection (10 mg/Kg) 3 times per day. Atrial fibroblasts isolated from canines were treated with angiotensin II or adenovirus carrying the SK4 gene (Ad-SK4) to overexpress SK4 channels. Results: TRAM-34 treatment significantly suppressed the increased intra-atrial conducting time (CT) and AF duration in canines after rapid atrial pacing (P<0.05). Compared with the sham group, the expression of SK4 in atria was higher in the pacing group, which was associated with an increased number of myofibroblasts and levels of extracellular matrix in atrium (all P<0.05), and this effect was reversed by TRAM-34 treatment (all P<0.05). In atrial fibroblasts, the increased expression of SK4 induced by angiotensin II stimulation or Ad-SK4 transfection contributed to higher levels of P38, ERK1/2 and their downstream factors c-Jun and c-Fos, leading to the increased expression of α-SMA (all P<0.05), and all these increases were markedly reduced by TRAM-34 treatment. Conclusion: SK4 blockade suppressed AF by attenuating cardiac fibroblast activity and atrial fibrosis, which was realized through not only a decrease in fibrogenic factors but also inhibition of fibrotic signaling pathways.

Molecular Characteristics and Risk Factors of Bloodstream Infection Caused by Escherichia coli ST131 in Southeast China.

BACKGROUND: E. coli ST131 is the predominant lineage among extraintestinal pathogenic E. coli isolates worldwide and is an important pathogen associated with all kinds of human infections. The aim of this study was to investigate the prevalence and molecular characteristics of E. coli ST131 and non-ST131 isolates that cause bloodstream infections and evaluate the risk factors for E. coli ST131. METHODS: A total of 103 E. coli isolates associated with bloodstream infection were collected between August 2014 and August 2015 at a Chinese university hospital. The isolates were classified into ST131 and non-ST131 E. coli groups by multilocus sequence typing. Phylogenetic analysis, susceptibility testing, virulence genotyping, PCR-based O typing, and pulsed-field gel electrophoresis (PFGE) were performed, and the clinical features of patients in both groups were compared. RESULTS: Overall, 12 isolates (11.7%) were identified as ST131 isolates, including 10 O25b-ST131 (83.3%) and 2 O16-ST131 (16.7%) clones. All 103 E. coli isolates were divided into four phylogenetic groups: B2 was the predominant phylogenetic group (n = 39, 37.9%), and it was followed in descending order by D (n = 33, 32.0%), A (n = 20, 19.4%), and B1 (n = 11, 10.7%). Compared with the non-ST131 isolates, the E. coli ST131 isolates harbored more virulence factors and were associated with a significantly higher incidence of urinary tract infection (p = 0.040) and a significantly greater length of hospital stay (p = 0.045). According to PFGE analysis, the molecular features of the E. coli ST131 isolates were highly diverse, and there was no dominant clone. CONCLUSIONS: The ST131 isolates collected from Southeast China in this study exhibited strong virulence and multiple drug resistance, and the main serotype was O25b-ST131. Therefore, future studies should focus on O16-ST131 subclones in order to better understand the prognosis of patients with bloodstream infection caused by E. coli ST131.

Pathogenic Characteristics and Genomic Analysis of a Rare Serotype Salmonella enterica Serovar Moualine Isolated from the Blood.

BACKGROUND: Salmonella is composed of a wide variety of serovars that cause human self-limited gastrointestinal illnesses or invasive infections. Most of the Salmonella strains of clinical isolates belong to the A - F group. In December 2012, a case of invasive infection was caused by a rare Salmonella, Salmonella enterica serovar Moualine (S. Moualine), identified as 047 outside of groups A - F, which was easily missed or misreported. The goal is to ex-plore clinical symptoms and therapies of blood infection caused by S. Moualine and to provide theoretical basis and molecular level date for Salmonella research by analyzing pathogenic characteristics and genome information of S. Moualine. METHODS: The S. Moualine genome was sequenced using a PacBio RS II platform and Illumina HiSeq 4000 platform and analysis for serotyping serovars, ST types, the characterization of antibiotic resistance, virulence and phylogeny. RESULTS: The clinical symptoms were mainly irregular recurrent fever, lasting 1 - 3 weeks, with mild gastrointestinal symptoms. The genome size of S. Moualine was 4,611,151 bp, the serotype was 047 (+), Hy (+), H1,6 (+), and multilocus sequence typing analysis was ST3038. S. Moualine contains the majority of virulence genes. Interestingly, S. Moualine also harbors the rck and Typhi colonization factor (tcf) genes, which may play a role in invasive infection. S. Moualine encodes 17 Salmonella pathogenicity islands and is potentially dangerous to human health. Both phenotypic and genomic characterizations have demonstrated that S. Moualine generally showed low antimicrobial resistance potential. CONCLUSIONS: There were few reports on S. Moualine. According to clinical symptoms and genetic analysis, S. Moualine was predicted to be a highly virulent bacteria and was also potentially dangerous to health of humans. This study highlights that the transparency of global surveillance genomic data could accelerate the understanding of the virulence and antimicrobial resistance makeup of a previously unknown threat.

Substrate stiffness promotes dentinogenesis via LAMB1-FAK-MEK1/2 signaling axis.

OBJECTIVES: In vivo, the principal function of mechanosensitive odontoblasts is to synthesize and secrete the matrix which then calcifies and forms reactive dentin after exposure to appropriate stimuli. This study aims to develop the influence of mechanical factors on dentinogenesis based on odontoblasts, which contribute to reparative dentin formation. METHODS: We fabricated polydimethylsiloxane with different stiffnesses and seeded 17IIA11 odontoblast-like cells on the substrates in different stiffnesses. Cell morphology was detected by scanning electron microscope, and the mineralization phenotype was detected by alkaline phosphatase staining and alizarin red staining, while expression levels of dentinogenesis-related genes (including Runx2, Osx, and Alp) were assayed by qPCR. To explore mechanism, protein distribution and expression levels were detected by immunofluorescent staining, Western blotting, and immunoprecipitation. RESULTS: In our results, during dentinogenesis, 17IIA11 odontoblast-like cells appeared better extension on stiffer substrates. The binding between LAMB1 and FAK contributed to converting mechanical stimuli into biochemical signaling, thereby controlling mitogen-activated protein kinase kinase 1/2 activity in stiffness-driven dentinogenesis. CONCLUSION: The present study suggests odontoblast behaviors can be directly regulated by mechanical factors at cell-material interfaces, which offers fundamental mechanism in remodeling cell microenvironment, thereby contributing to physiological phenomena explanation and tissue engineering progress.

TIM-mediated inhibition of HIV-1 release is antagonized by Nef but potentiated by SERINC proteins.

The T cell Ig and mucin domain (TIM) proteins inhibit release of HIV-1 and other enveloped viruses by interacting with cell- and virion-associated phosphatidylserine (PS). Here, we show that the Nef proteins of HIV-1 and other lentiviruses antagonize TIM-mediated restriction. TIM-1 more potently inhibits the release of Nef-deficient relative to Nef-expressing HIV-1, and ectopic expression of Nef relieves restriction. HIV-1 Nef does not down-regulate the overall level of TIM-1 expression, but promotes its internalization from the plasma membrane and sequesters its expression in intracellular compartments. Notably, Nef mutants defective in modulating membrane protein endocytic trafficking are incapable of antagonizing TIM-mediated inhibition of HIV-1 release. Intriguingly, depletion of SERINC3 or SERINC5 proteins in human peripheral blood mononuclear cells (PBMCs) attenuates TIM-1 restriction of HIV-1 release, in particular that of Nef-deficient viruses. In contrast, coexpression of SERINC3 or SERINC5 increases the expression of TIM-1 on the plasma membrane and potentiates TIM-mediated inhibition of HIV-1 production. Pulse-chase metabolic labeling reveals that the half-life of TIM-1 is extended by SERINC5 from <2 to ∼6 hours, suggesting that SERINC5 stabilizes the expression of TIM-1. Consistent with a role for SERINC protein in potentiating TIM-1 restriction, we find that MLV glycoGag and EIAV S2 proteins, which, like Nef, antagonize SERINC-mediated diminishment of HIV-1 infectivity, also effectively counteract TIM-mediated inhibition of HIV-1 release. Collectively, our work reveals a role of Nef in antagonizing TIM-1 and highlights the complex interplay between Nef and HIV-1 restriction by TIMs and SERINCs.

Guillain-​Barré Syndrome Associated with COVID-19 Vaccination.

We conducted a multi-institutional study in Taiwan and a systematic review of the literature for reports of Guillain-​Barré syndrome after coronavirus disease vaccination. This condition, mostly the classic form and the acute inflammatory demyelinating polyneuropathy subtype, has been reported in 39 cases and has occurred within 2 weeks of vaccine administration.

Stable reflective state induced by a disturbed planar texture in surface-treatment-free chiral nematic liquid crystals.

Chiral nematic liquid crystals possess a one-dimensional periodic helical structure and are one of the oldest known materials with the ability of selective reflection of light. Their helix orientation, determining their optical properties, can be changed by a variety of stimuli, and it is also dominated by the surface treatment, ratio of the elastic constants and cell thickness. Here, we present a simple method to realize an angular independence reflective state, induced by a stable disturbed planar texture, in a surface-treatment-free chiral nematic liquid crystal cell. The scattering state caused by the defect-rich focal-conic texture can be electrically tuned to the reflective state from the disturbed planar texture in a very short time, and vice versa. These two optical conditions are both stable states in the null field until the next trigger. We find that the disturbed planar texture in the chiral nematic can provide a 100° viewing angle without reflected wavelength shift. The gray level of the reflected intensity can be tuned via application of the voltage pulses. Moreover, in this work, we discuss the effect of the chiral concentration on stabilizing the disturbed planar texture. When the chiral concentration is higher to induce the blue phases, the change in the texture of the ChNLCs after removing the strong electric field can stop at the disturbed planar texture with high reflectivity. In this work, the optical performance and the bistability based on the disturbed planar texture exhibits great potential for many applications, such as tunable filters, see-through/reflective displays and large-area smart windows.

Effect of fumonisin B1 on oxidative stress and gene expression alteration of nutrient transporters in porcine intestinal cells.

Fumonisin B1 (FB1 ) is a common environmental mycotoxin produced by molds such as Fusarium verticillioides. The toxin poses health risks to domestic animals, including pigs, through FB1 -contaminanted feed. However, the cytotoxicity of FB1 to porcine intestines has not been fully analyzed. In the present study, the effects of FB1 on oxidative stress and nutrient transporter-associated genes of the porcine intestinal IPEC-J2 cells were explored. FB1 decreased IPEC-J2 proliferation but did not trigger reactive oxygen species (ROS) overproduction. Meanwhile, FB1 reduced the expression levels of the transporters l-type amino acid transporter-1 (y+ LAT1), solute carrier family 7 member 1 (SLC7A1), solute carrier family 1 member 5 (ASCT2), and excitatory amino acid carrier 1 (EAAC1); in addition, FB1 reduced the levels of the fatty acid transporters long-chain fatty acid transport protein 1 (FATP1) and long-chain fatty acid transport protein 4 (FATP4) as well as glucose transporters Na+ /glucose cotransporter 1 (SGLT1) and glucose transporter 2 (GLUT2). FB1 stimulation increased the expression levels of peptide transporter peptide transporter 1 (PepT1) and metal ion transport-related gene zinc transporter 1 (ZNT1). Moreover, metal ion transporter divalent metal transporter 1 (DMT1) expression was depressed by a higher dosage of FB1 . The data indicate that FB1 results in aberrant expression of nutrient transporters in IPEC-J2 cells, thereby exerting its toxicity even though it fails to exert ROS-dependent oxidative stress.

Utilization of a styrene-derived pathway for 2-phenylethanol production in budding yeast.

2-Phenylethanol (2-PE) is an important flavor ingredient and is widely applied in the fields of food, cosmetics, and pharmaceuticals. Despite that Saccharomyces cerevisiae has the ability to naturally synthesize 2-PE via the Ehrlich pathway, de novo synthesis of 2-PE in high titer still remains a huge challenge. In this study, a non-native styrene degradation pathway was introduced into S. cerevisiae, which represents the first time to demonstrate the functional expression of "styrene-derived" 2-PE synthesis in yeast. Using a host strain engineered with L-phenylalanine (L-Phe) overproduction, the heterologous 2-PE pathway coupled with endogenous Ehrlich pathway produced 233 mg/L 2-PE under shake flasks. Additionally, we further engineered the permease transporters to improve the intracellular L-Phe availability, and further improved the 2-PE titer to 680 mg/L. Taken together, our work represents one of the pioneering reports to explore "styrene-derived" pathway in S. cerevisiae. The synthetic yeast described here might be used as a platform for the future development of next-generation high-yielding 2-PE yeast strains.Key Points• A styrene-derived pathway was established in yeast for 2-phenylethanol productions; membrane-associated styrene oxide isomerase was functional in yeast.• Transporter engineering to improve the L-phenylalanine importation with enhanced 2-phenylethanol productions.