Perfluorooctane sulfonate-induced Sertoli cell injury through c-Jun N-terminal kinase: a study by RNA-Seq.

Per- and polyfluoroalkyl substances (PFASs) are a family of "forever chemicals" including perfluorooctane sulfonate (PFOS). These toxic chemicals do not break down in the environment or in our bodies. In the human body, PFOS and perfluoroctanoic acid (PFOA) have a half-life (T1/2) of about 4-5 yr so low daily consumption of these chemicals can accumulate in the human body to a harmful level over a long period. Although the use of PFOS in consumer products was banned in the United States in 2022/2023, this forever chemical remains detectable in our tap water and food products. Every American tested has a high level of PFAS in their blood (https://cleanwater.org/pfas-forever-chemicals). In this report, we used a Sertoli cell blood-testis barrier (BTB) model with primary Sertoli cells cultured in vitro with an established functional tight junction (TJ)-permeability barrier that mimicked the BTB in vivo. Treatment of Sertoli cells with PFOS was found to perturb the TJ-barrier, which was the result of cytoskeletal disruption across the cell cytoplasm, disrupting actin and microtubule polymerization. These changes thus affected the proper localization of BTB-associated proteins at the BTB. Using RNA-Seq transcriptome profiling, bioinformatics analysis, and pertinent biochemical and cell biology techniques, it was discovered that PFOS -induced Sertoli cell toxicity through the c-Jun N-terminal kinase (JNK; also known as stress-activated protein kinase, SAPK) and its phosphorylated/active form p-JNK signaling pathway. More importantly, KB-R7943 mesylate (KB), a JNK/p-JNK activator, was capable of blocking PFOS-induced Sertoli cell injury, supporting the notion that PFOS-induced cell injury can possibly be therapeutically managed.NEW & NOTEWORTHY PFOS induces Sertoli cell injury, including disruption of the 1) blood-testis barrier function and 2) cytoskeletal organization, which, in turn, impedes male reproductive function. These changes are mediated by JNK/p-JNK signaling pathway. However, the use of KB-R7943, a JNK/p-JNK activator was capable of blocking PFOS-induced Sertoli cell injury, supporting the possibility of therapeutically managing PFOS-induced reproductive dysfunction.

Catalyst-Free Oxidation of Styrene to Styrene Oxide Using Circulating Microdroplets in an Oxygen Atmosphere.

Water microdroplets possess unique interfacial properties that enable chemical reactions to occur spontaneously and increase the reaction rate by orders of magnitude. In this study, water containing styrene (SY) was cyclically sprayed into the air to form microdroplets with an average diameter of 6.7 µm. These microdroplets allowed SY to be oxidized into styrene oxide (SO) without catalysts. No oxidation products of SY were observed in the bulk solution under the same conditions, while in microdroplet reactions 4.2% conversion of SY with approximately 3.1 mM SO was detected. Compared with the traditional spraying microdroplet method, the oxidation product concentration was enhanced by 1000 times. Experiments proved that an aerobic environment boosts SY oxidation, leading to a proposed dual-path hydrogen peroxide (H2O2) oxidation mechanism at the droplet interface. This was confirmed by density functional theory calculations (DFT). Furthermore, in the presence of additional ultrasound, the SY oxidation process initiated by water droplets can be further enhanced, and 7.0% conversion of SY with approximately 5.2 mM SO was detected. The cyclic spraying method greatly enhanced the oxidation product concentration, showing the potential for large scale chemical production using microdroplets.

A Novel CRISPR/Cas12a-Mediated Ratiometric Dual-Signal Electrochemical Biosensor for Ultrasensitive and Reliable Detection of Circulating Tumor Deoxyribonucleic Acid.

Circulating tumor DNA (ctDNA) holds great promise as a noninvasive biomarker for cancer diagnosis, treatment, and prognosis. However, the accurate and specific quantification of low-abundance ctDNA in serum remains a significant challenge. This study introduced, for the first time, a novel exponential amplification reaction (EXPAR)-assisted CRISPR/Cas12a-mediated ratiometric dual-signal electrochemical biosensor for ultrasensitive and reliable detection of ctDNA. To implement the dual-signal strategy, a signal unit (ssDNA-MB@Fc/UiO-66-NH2) was prepared, consisting of methylene blue-modified ssDNA as the biogate to encapsulate ferrocene signal molecules within UiO-66-NH2 nanocarriers. The presence of target ctDNA KRAS triggered EXPAR amplification, generating numerous activators for Cas12a activation, resulting in the cleavage of ssDNA-P fully complementary to the ssDNA-MB biogate. Due to the inability to form a rigid structure dsDNA (ssDNA-MB/ssDNA-P), the separation of ssDNA-MB biogate from the UiO-66-NH2 surface was hindered by electrostatic interactions. Consequently, the supernatant collected after centrifugation exhibited either no or only a weak presence of Fc and MB signal molecules. Conversely, in the absence of the target ctDNA, the ssDNA-MB biogate was open, leading to the leakage of Fc signal molecules. This clever ratiometric strategy with Cas12a as the "connector", reflecting the concentration of ctDNA KRAS based on the ratio of the current intensities of the two electroactive signal molecules, enhanced detection sensitivity by at least 60-300 times compared to single-signal strategies. Moreover, this strategy demonstrated satisfactory performance in ctDNA detection in complex human serum, highlighting its potential for cancer diagnosis.

Versatile design for temporal shape control of high-power nanosecond pulsed fiber laser amplifier.

This research proposed a novel pulse-shaping design for directly shaping distorted pulses after the amplification. Based on the principle of the design we made a pulse shaper. With this pulse shaper, we successfully manipulate the pulse's leading edge and width to achieve an 'M'-shaped waveform in an amplification system. Comparative experiments were conducted within this system to compare the output with and without the integration of the pulse shaper. The results show a significant suppression of the nonlinear effect upon adding the pulse shaper. This flexible and effective pulse shaper can be easily integrated into a high-power all-fiber system, supplying the capability to realize the desired output waveform and enhance the spectral quality.

High repetition frequency tunability active Q-switched all-fiber laser by multi-gain sub-rings smoothing multipeak pulse and suppressing ASE self-saturation.

This paper provides a method to effectively suppress the severe ASE self-saturation when achieving high repetition frequency tunability with high output power and narrow pulse width in active Q-switched all-fiber lasers. By studying the regularity of the system's multi-stable state, we first ensured that the laser system operated in a steady state. Then output avoids uneven distribution of pulse energy or missing pulses due to period bifurcation state or chaos state. By adding multiple gain sub-rings within the cavity, the sub-ring structure itself indirectly mitigates the ASE self-saturation while smoothing the pulse. The method will avoid the severe power loss caused by traditional smoothing methods by adjusting the AOM rising edge time. It will also avoid lowering the ASE lasing threshold at high repetition frequency. Meanwhile, the intra-cavity backward ASE can be effectively absorbed by inserting the gain fiber in the sub-rings to directly mitigate the ASE self-saturation. The system's continuously adjustable repetition frequency can be as high as over 300 kHz. It ensures that output power above the watt level and a < 0.2 nm narrow bandwidth can be maintained while tuning the repetition frequency. The narrowest smoothing pulse width of 28 ns has been reached.

Association between NOS3 gene polymorphisms and genetic susceptibility to congenital heart Disease: A systematic review and meta-analysis.

BACKGROUND: Endothelial nitric oxide (NO) produced by endothelial Nitric Oxide Synthase (eNOS) can promote the expression of pro-angiogenic cytokines and is favorable for angiogenesis. However, the relationship between NOS3 gene polymorphisms and genetic susceptibility to congenital heart disease (CHD) was still unclear. METHODS: We searched five databases including Pubmed, Cochrane Library, Embase, Web of Science, CNKI, and Wan Fang, to find all studies on NOS3 gene polymorphisms and CHD. Rstudio was used to merge the data included in the study to obtain OR, 95%CI, and forest plots. RESULTS: Five relevant literatures were included, including three sites of NOS3 gene, rs1799983 (G894T), rs2070744 (T-786C), and rs7830 (G10T). Several models including the homozygous model of rs1799983 (G894T) gene polymorphism (TT VS GG: OR = 1.602, 95%CI: 1.098 âˆ¼ 2.337, P = 0.027), rs7830 (G10T) gene polymorphism allele model (A VS C: OR = 1.171, 95%CI: 1.029 âˆ¼ 1.333, P = 0.017), homozygous model (AA VS CC: OR = 1.474, 95%CI: 1.122 âˆ¼ 1.936, P = 0.005) and implicit model (AA VS CC + AC: OR = 1.451, 95%CI: 1.133 âˆ¼ 1.859, P = 0.003) indicated that there was a correlation. The results of the combined analysis of each gene model of rs2070744 (T-786C) gene polymorphism sites were not statistically significant, and their P values were all>0.05. CONCLUSION: rs1799983 (G894T) and rs7830 (G10T) polymorphic sites might play a role in the susceptibility of sporadic congenital heart disease and increase the risk of CHD. Yet, it is still necessary to expand the sample size and conduct more prospective/retrospective studies to confirm whether the rs2070744 (T-786C) polymorphism tended to increase the incidence of CHD.

Blocking the HIF-1α/glycolysis axis inhibits allergic airway inflammation by reducing ILC2 metabolism and function.

BACKGROUND: The role of lung group 2 innate lymphoid cell (ILC2) activation in allergic asthma is increasingly established. However, the regulatory mechanisms underlying hypoxia-inducible factor-1α (HIF-1α)-mediated glycolysis in ILC2-mediated allergic airway inflammation remain unclear. OBJECTIVE: To investigate the role of the HIF-1α/glycolysis axis in ILC2-mediated allergic airway inflammation. METHODS: Glycolysis and HIF-1α inhibitors were used to identify their effect on the function and glucose metabolism of mouse and human ILC2s in vivo and vitro. Blocking glycolysis and HIF-1α in mice under interleukin-33 (IL-33) stimulation were performed to test ILC2 responses. Conditional HIF-1α-deficient mice were used to confirm the specific role of HIF-1α in ILC2-driven airway inflammation models. Transcriptomic, metabolic, and chromatin immunoprecipitation analyses were performed to elucidate the underlying mechanism. RESULTS: HIF-1α is involved in ILC2 metabolism and is crucial in allergic airway inflammation. Single-cell sequencing data analysis and qPCR confirmation revealed a significant upregulation of glycolysis-related genes, particularly HIF-1α, in murine lung ILC2s after IL-33 intranasal administration or injection. Treatment with the glycolysis inhibitor 2-deoxy-D-glucose (2-DG) and the HIF-1α inhibitor 2-methoxyestradiol (2-ME) abrogated inflammation by suppressing ILC2s function. Conditional HIF-1α-deficient mice showed reduced ILC2 response and airway inflammation induced upon IL-33 or house dust mite (HDM) stimulation. Transcriptome and metabolic analyses revealed significantly impaired glycolysis in lung ILC2s in conditional HIF-1α knockout mice compared to that in their littermate controls. Chromatin immunoprecipitation results confirmed the transcriptional downregulation of glycolysis-related genes in HIF-1α-knockout and 2-DG-treated mice. Furthermore, impaired HIF-1α/glycolysis axis activation is correlated with downregulated ILC2 in patients with asthma. CONCLUSION: The HIF-1α/glycolysis axis is critical for controlling ILC2 responses in allergic airway inflammation and has potential immunotherapeutic value in asthma.

Sperm immotility is associated with epididymis metabolism disorder in mice under obstructive azoospermia.

Obstructive azoospermia (OA) accounts for approximately 40% of males who suffer from azoospermia of male infertility. Currently, available treatment for OA consists of reproductive tract surgical reconstruction and sperm retrieval from the testis. However, both treatments result in low fertility compared to normal pregnancy, and the main reason remains largely unknown. Previous studies have shown that the quality of sperm retrieved from OA patients is poor compared with normal adult males but without an in-depth study. Herein, we generated a mouse OA model with vasectomy to evaluate sperm quality systematically. Our results showed that the testis had normal spermatogenesis but increased apoptotic activity in both OA patients and mice. More importantly, epididymal morphology was abnormal, with swollen epididymal tubules and vacuole-like principal cells. Especially, sperm retrieved from the epididymis of OA mice showed poor motility and low fertilization ability in vitro. Using mass spectrometry in epididymal fluid, we found differences in the expression of key proteins for sperm maturation, such as Angiotensinogen (AGT), rhophilin-associated tail protein 1 (ROPN1), NPC intracellular cholesterol transporter 2 (NPC2), and prominin 1 (PROM1). Furthermore, our results demonstrated that AGT, secreted by epididymal principal cells, could regulate sperm motility by managing PKCα expression to modify sperm phosphorylation. In conclusion, our data evaluate sperm quality systematically in OA mice and contribute to the understanding between the sperm and epididymis, which may provide novel insight into treating male infertility.

Theoretical insights into the enantiodivergence induced by chiral phosphoric acid catalysis with a Lewis acid for the synthesis of N-N axially chiral atropisomers.

A detailed theoretical mechanistic investigation on chiral phosphoric acid (CPA)-catalyzed Paal-Knorr reactions, in the presence and absence of a Lewis acid, for the synthesis of N-N axially chiral atropisomers is described herein. Density functional theory (DFT) studies elucidate that in the absence of a Lewis acid, CPA catalyzes both the initial cyclization and the subsequent dehydroxylation processes, ambiguously identified as the rate-determining step in the reactions. Conversely, when a Lewis acid participates in the reaction, it facilitates the second dehydroxylation process with a significantly lower energy barrier, thereby reversing the rate-determining step to the initial cyclization step. It is noteworthy that in the case of N-aminoindoles, both the S-configurational transition state TS1 in the cyclization step and TS2 in the dehydroxylation process are favourable. In contrast, for the synthesis of a bispyrrole, the R-configurational TS1 and the S-configurational TS2 are dominant. Therefore, the enantiodivergence observed is essentially induced by the reversed rate-determining steps in the absence or presence of a Lewis acid in the case of a bispyrrole. Furthermore, the non-covalent interaction (NCI) and atoms-in-molecules (AIM) analysis of the TS structures reveal that the non-covalent interactions play a pivotal role in determining the enantiodivergence observed in these reactions.

Repetitive transcranial magnetic stimulation rescues simulated space complex environment-induced emotional and social impairments by enhancing neuronal excitability in the medial prefrontal cortex.

Studies have shown that spaceflight affects the emotional and social performance of astronauts. Identifying the neural mechanisms underlying the emotional and social effects of spacefaring-specific environments is essential to specify targeted treatment and prevention interventions. Repetitive transcranial magnetic stimulation (rTMS) has been shown to improve the neuronal excitability and is used to treat psychiatric disorders such as depression. To study the changes of excitatory neuron activity in medial prefrontal cortex (mPFC) in simulated space complex environment (SSCE), and to explore the role of rTMS in behavioral disorders caused by SSCE and the neural mechanism. We found that rTMS effectively ameliorated the emotional and social impairments of mice in SSCE, and acute rTMS could instantaneously enhance the excitability of mPFC neurons. During depression-like and social novelty behaviors, chronic rTMS enhanced the mPFC excitatory neuronal activity that was inhibited by SSCE. Above results suggested that rTMS can completely reverse the SSCE-induced mood and social impairment by enhancing the suppressed mPFC excitatory neuronal activity. It was further found that rTMS suppressed the SSCE-induced excessive dopamine D2 receptor expression, which may be the cellular mechanism by which rTMS potentiates the SSCE-evoked hypoactive mPFC excitatory neurons. Our current results raise the possibility of rTMS being applied as a novel neuromodulation for mental health protection in spaceflight.

Aquibaculum sediminis sp. nov., a halotolerant bacteria isolated from salt lake sediment.

An aerobic, Gram-stain negative bacterium was isolated from sediment samples of Barkol salt lake in Hami City, Xinjiang Uygur Autonomous Region, China, with the number EGI_FJ10229T. The strain is ellipse-shaped, oxidase-negative, catalase-positive, and has white, round, smooth, opaque colonies on marine 2216 E agar plate. Growth occurs at 4.0-37.0 â„ƒ (optimal:30.0 â„ƒ), pH 7.0-9.0 (optimal: pH 8.0) and NaCl concentration of 0-8.0% (optimal: 3.0%). Phylogenetic analysis based on 16S rRNA gene and genome sequences indicated that the isolated strain should be assigned to the genus Aquibaculum and was most closely related to Aquibaculum arenosum CAU 1616 T. Average nucleotide identity (ANI) and Average amino-acid identity (AAI) values between the type species of the genus Aquibaculum and other related type species were lower than the threshold values recommended for bacterial species. The genomic DNA G + C content of EGI_FJ10229T was 65.41%. The major polar lipids were diphosphatidylglycerol, phosphatidylmethylethanolamine, phosphatidylcholine, phosphatidylethanolamine and unidentified phospholipid. The major fatty acids (> 5%) were C19:0 cyclo ω8c (42.0%) and C18:1 ω7c (33.78%). The respiratory quinone identified was Q-10. Differential phenotypic and genotypic characteristics of this strain and species of genus Aquibaculum showed that the strain should be classified as representing a new species belonging to this genus, for which the name Aquibaculum sediminis sp. nov. is proposed. The type strain of the proposed novel species is EGI_FJ10229T (= KCTC 8570 T = GDMCC 1.4598 T).

Association of ambient PM2.5 and its components with in vitro fertilization outcomes: The modifying role of maternal dietary patterns.

Despite the associations of dietary patterns and air pollution with human reproductive health have been demonstrated, the interaction of maternal preconception diet and PM2.5 and its components exposure on in vitro fertilization (IVF) treatment outcomes has not been investigated. A total of 2688 couples from an ongoing prospective cohort were included. Principle component analysis with varimax rotation was performed to determine dietary patterns. One-year and 85-day average PM2.5 and its components exposure levels before oocyte retrieval were estimated. Generalized linear regression models were conducted to assess the association of dietary patterns and PM2.5 and its components exposure with IVF outcomes. Interactive effects of dietary patterns on the association between PM2.5 and its components and IVF outcomes were evaluated by stratified analyses based on different dietary patterns. A positive association between the "Fruits-Vegetables-Dairy" pattern and normal fertilization (p-trend = 0.009), Day 3 available embryos (p-trend = 0.048), and top-quality embryos (p-trend = 0.041) was detected. Conversely, women with higher adherence to the "Puffed food-Bakery-Candy" pattern were less likely to achieve Day 3 available embryos (p-trend = 0.042) and top-quality embryos (p-trend = 0.030), clinical pregnancy (p-trend = 0.049), and live birth (p-trend = 0.020). Additionally, increased intake of animal organs and seafood improved the odds of live birth (p-trend = 0.048). Exposure to PM2.5, SO42-, organic matter (OM), and black carbon (BC) had adverse effects on embryo development and pregnancy outcomes. Furthermore, our findings indicated that the effects of PM2.5 components exposure on normal fertilization and embryo quality were modified by the "Grains-Tubers-Legumes". Moreover, moderate intake of animal organs and seafood appeared to attenuate the effect of NO3- and NH4+ on the risk of early abortion. Our findings provide human evidence of the interaction between dietary patterns and PM2.5 exposure on IVF outcomes during preconception, implicating the potential for dietary interventions in infertile women to improve reproductive outcomes under conditions of unavoidable ambient air-pollutant exposure.

Triptolide exposure triggers testicular vacuolization injury by disrupting the Sertoli cell junction and cytoskeletal organization via the AKT/mTOR signaling pathway.

BACKGROUND: Despite the known reproductive toxicity induced by triptolide (TP) exposure, the regulatory mechanism underlying testicular vacuolization injury caused by TP remains largely obscure. METHODS: Male mice were subjected to TP at doses of 15, 30, and 60 µg/kg for 35 consecutive days. Primary Sertoli cells were isolated from 20-day-old rat testes and exposed to TP at concentrations of 0, 40, 80, 160, 320, and 640 nM. A Biotin tracer assay was conducted to assess the integrity of the blood-testis barrier (BTB). Transepithelial electrical resistance (TER) assays were employed to investigate BTB function in primary Sertoli cells. Histological structures of the testes and epididymides were stained with hematoxylin and eosin (H&E). The expression and localization of relevant proteins or pathways were assessed through Western blotting or immunofluorescence staining. RESULTS: TP exposure led to dose-dependent testicular injuries, characterized by a decreased organ coefficient, reduced sperm concentration, and the formation of vacuolization damage. Furthermore, TP exposure disrupted BTB integrity by reducing the expression levels of tight junction (TJ) proteins in the testes without affecting basal ectoplasmic specialization (basal ES) proteins. Through the TER assay, we identified that a TP concentration of 160 nM was optimal for elucidating BTB function in primary Sertoli cells, correlating with reductions in TJ protein expression. Moreover, TP exposure induced changes in the distribution of the BTB and cytoskeleton-associated proteins in primary Sertoli cells. By activating the AKT/mTOR signaling pathway, TP exposure disturbed the balance between mTORC1 and mTORC2, ultimately compromising BTB integrity in Sertoli cells. CONCLUSION: This investigation sheds light on the impacts of TP exposure on testes, elucidating the mechanism by which TP exposure leads to testicular vacuolization injury and offering valuable insights into comprehending the toxic effects of TP exposure on testes.

CRISPR/Cas12a-coupled multiplexed strand displacement amplification for miRNA155 one-tube detection: via a dual-cavity PCR tube.

A CRISPR/Cas12a-coupled multiplexed strand displacement amplification (CMSDA) for the detection of miR155 has been developed. Non-specific amplification was avoided by designing a single-stranded DNA template with a hairpin structure. The detection target miR155 was used as a primer to initiate a multiple-strand displacement reaction to produce abundant ssDNA. ssDNA was recognized by the Cas12a/CrRNA binary complex, activating the trans-cleaving activity of Cas12a. The multiple-strand displacement reaction is more efficiently detected compared with a single-strand displacement reaction. The detection range is from 250 pM to 1 nM, and the limit of the detection is 6.5 pM. The proposed method showed a good applicability in complex serum environments, indicating that the method has a broad prospect for disease detection and clinical application. In addition, we designed a dual-cavity PCR tube, which realized one-tube detection of miRNA155 and avoided open-cap contamination.

Modulation of Acute Intestinal Inflammation by Dandelion Polysaccharides: An In-Depth Analysis of Antioxidative, Anti-Inflammatory Effects and Gut Microbiota Regulation.

Acute colitis is a complex disease that can lead to dysregulation of the gut flora, inducing more complex parenteral diseases. Dandelion polysaccharides (DPSs) may have potential preventive and therapeutic effects on enteritis. In this study, LPS was used to induce enteritis and VC was used as a positive drug control to explore the preventive and therapeutic effects of DPS on enteritis. The results showed that DPS could repair the intestinal barrier, down-regulate the expression of TNF-α, IL-6, IL-1ß, and other pro-inflammatory factors, up-regulate the expression of IL-22 anti-inflammatory factor, improve the antioxidant capacity of the body, and improve the structure of intestinal flora. It is proved that DPS can effectively prevent and treat LPS-induced acute enteritis and play a positive role in promoting intestinal health.

Orienting Group Directed Cascade Borylation for Efficient One-Shot Synthesis of 1,4-BN-Doped Polycyclic Aromatic Hydrocarbons as Narrowband Organic Emitters.

1,4-BN-doped polycyclic aromatic hydrocarbons (PAHs) have emerged as very promising emitters in organic light-emitting diodes (OLEDs) due to their narrowband emission spectra that may find application in high-definition displays. While considerable research has focused on investigating the properties of these materials, less attention has been placed on their synthetic methodology. Here we developed an efficient synthetic method for 1,4-BN-doped PAHs, which enables sustainable production of narrowband organic emitting materials. By strategically introducing substituents, such as methyl, tert-butyl, phenyl, and chloride, at the C5 position of the 1,3-benzenediamine substrates, we achieved remarkable regioselective borylation in the para-position of the substituted moiety. This approach facilitated the synthesis of a diverse range of 1,4-BN-doped PAHs emitters with good yields and exceptional regioselectivity. The synthetic method demonstrated excellent scalability for large-scale production and enabled late-stage transformation of the borylated products. Mechanistic investigations provided valuable insights into the pivotal roles of electron effect and steric hindrance effect in achieving highly efficient regioselective borylation. Moreover, the outstanding device performance of the synthesized compounds 10 b and 6 z, underscores the practicality and significance of the developed method.

Chemoselective Construction of Polycyclic Heterocycles Containing a [6-6-5] or [7-6-5] Tricyclic Core Skeleton from a 2-Isocyanophenyl Propargylic Ester.

Functionalized isocyanide chemistry represents an important research area in organic synthesis. A structurally unique 2-isocyanophenl propargylic ester has been designed to incorporate the reactivity of isocyanide and propargylic ester. Thus, the reaction of 2-isocyanophenyl propargylic ester and 2-aminoaromatic aldimine facilitates the synthesis of a wide range of polycyclic benzo[b]indolo[3,2-h][1,6]naphthyridine derivatives. Furthermore, reacting with 2-hydroxyaromatic aldimine enables the divergent synthesis of both the aforementioned scaffolds and another structurally distinctive diazabenzo[f]naphtho[2,3,4-ij]azulenes featuring a [7-6-5] core skeleton. Experimental results and DFT calculations suggest that these transformations likely proceed via the in situ generation of a strained cyclopropen-imine species followed by [3+2] cycloaddition. Next, switchable nucleophilic attack/ring-expansion/aromatization and nucleophilic addition/ring-expansion/elimination account for the observed selectivity.

CRISPR/Cas12a-Powered EC/FL Dual-Mode Controlled-Release Homogeneous Biosensor for Ultrasensitive and Cross-Validated Detection of Messenger Ribonucleic Acid.

Accurate detection of cancer-associated mRNAs is beneficial to early diagnosis and potential treatment of cancer. Herein, for the first time, we developed a novel CRISPR/Cas12a-powered electrochemical/fluorescent (EC/FL) dual-mode controlled-release homogeneous biosensor for mRNA detection. A functionalized ssDNA P2-capped Fe3O4-NH2 loaded with methylene blue (P2@MB-Fe3O4-NH2) was synthesized as the signal probe, while survivin mRNA was chosen as the target RNA. In the presence of the target mRNA, the nicking endonuclease-mediated rolling circle amplification (NEM-RCA) was triggered to produce significant amounts of ssDNA, activating the collateral activity of Cas12a toward the surrounding single-stranded DNA. Thus, the ssDNA P1 completely complementary to ssDNA P2 was cleaved, resulting in that the ssDNA P2 bio-gate on Fe3O4-NH2 could not be opened due to electrostatic interactions. As a result, there was no or only a little MB in the supernatant after magnetic separation, and the measured EC/FL signal was exceedingly weak. On the contrary, the ssDNA P2 bio-gate was opened, enabling MB to be released into the supernatant, and generating an obvious EC/FL signal. Benefiting from the accuracy of EC/FL dual-mode cross-verification, high amplification efficiency, high specificity of NEM-RCA and CRISPR/Cas12a, and high loading of mesoporous Fe3O4-NH2 on signal molecules, the strategy shows aM-level sensitivity and single-base mismatch specificity. More importantly, the practical applicability of this dual-mode strategy was confirmed by mRNA quantification in complex serum environments and tumor cell lysates, providing a new way for developing a powerful disease diagnosis tool.

Tree peony transcription factor PrWRI1 enhances seed oil accumulation.

BACKGROUND: WRINKLED1 (WRI1) encodes a transcription factor, belonging to the APETALA2 (AP2) family, and plays a key role in regulating plant oil biosynthesis. As a newly woody oil crop, tree peony (Paeonia rockii) was notable for the abundant unsaturated fatty acids in its seed oil. However, the role of WRI1 during the accumulation of P. rockii seeds oil remains largely unknown. RESULTS: In this study, a new member of the WRI1 family was isolated from P. rockii and was named PrWRI1. The ORF of PrWRI1 consisted of 1269 nucleotides, encoding a putative protein of 422 amino acids, and was highly expressed in immature seeds. Subcellular localization analysis in onion inner epidermal cells showed that PrWRI1 was located at the nucleolus. Ectopic overexpression of PrWRI1 could significantly increase the total fatty acid content in Nicotiana benthamiana leaf tissue and even PUFAs in transgenic Arabidopsis thaliana seeds. Furthermore, the transcript levels of most genes related to fatty acids (FA) synthesis and triacylglycerol (TAG) assembly were also up-regulated in transgenic Arabidopsis seeds. CONCLUSIONS: Together, PrWRI1 could push carbon flow to FA biosynthesis and further enhance the TAG amount in seeds with a high proportion of PUFAs.

Unrecognized risk of perfluorooctane sulfonate in promoting conjugative transfers of bacterial antibiotic resistance genes.

Antibiotic resistance is a major global health crisis facing humanity, with horizontal gene transfer (HGT) as a principal dissemination mechanism in the natural and clinical environments. Perfluoroalkyl substances (PFASs) are emerging contaminants of global concern due to their high persistence in the environment and adverse effects on humans. However, it is unknown whether PFASs affect the HGT of bacterial antibiotic resistance. Using a genetically engineered Escherichia coli MG1655 as the donor of plasmid-encoded antibiotic resistance genes (ARGs), E. coli J53 and soil bacterial community as two different recipients, this study demonstrated that the conjugation frequency of ARGs between two E. coli strains was (1.45 ± 0.17) × 10-5 and perfluorooctane sulfonate (PFOS) at environmentally relevant concentrations (2-50 µg L-1) increased conjugation transfer between E. coli strains by up to 3.25-fold. Increases in reactive oxygen species production, cell membrane permeability, biofilm formation capacity, and cell contact in two E. coli strains were proposed as major promotion mechanisms from PFOS exposure. Weighted gene co-expression network analysis of transcriptome data identified a series of candidate genes whose expression changes could contribute to the increase in conjugation transfer induced by PFOS. Furthermore, PFOS also generally increased the ARG transfer into the studied soil bacterial community, although the uptake ability of different community members of the plasmid either increased or decreased upon PFOS exposure depending on specific bacterial taxa. Overall, this study reveals an unrecognized risk of PFOS in accelerating the dissemination of antibiotic resistance. IMPORTANCE Perfluoroalkyl substances (PFASs) are emerging contaminants of global concern due to their high persistence in the environment and adverse health effects. Although the influence of environmental pollutants on the spread of antibiotic resistance, one of the biggest threats to global health, has attracted increasing attention in recent years, it is unknown whether environmental residues of PFASs affect the dissemination of bacterial antibiotic resistance. Considering PFASs, often called "forever" compounds, have significantly higher environmental persistence than most emerging organic contaminants, exploring the effect of PFASs on the spread of antibiotic resistance is more environmentally relevant and has essential ecological and health significance. By systematically examining the influence of perfluorooctane sulfonate on the antibiotic resistance gene conjugative transfer, not only at the single-strain level but also at the community level, this study has uncovered an unrecognized risk of PFASs in promoting conjugative transfers of bacterial antibiotic resistance genes, which could be incorporated into the risk assessment framework of PFASs.