Biosynthesis of Arabinoside from Sucrose and Nucleobase via a Novel Multi-Enzymatic Cascade.

Arabinoside and derived nucleoside analogs, a family of nucleoside analogs, exhibit diverse typically biological activities and are widely used as antibacterial, antiviral, anti-inflammatory, antitumor, and other drugs in clinical and preclinical trials. Although with a long and rich history in the field of medicinal chemistry, the biosynthesis of arabinoside has only been sporadically designed and studied, and it remains a challenge. Here, we constructed an in vitro multi-enzymatic cascade for the biosynthesis of arabinosides. This artificial biosystem was systematically optimized, involving an exquisite pathway design, NADP+ regeneration, meticulous enzyme selection, optimization of the key enzyme dosage, and the concentration of inorganic phosphate. Under the optimized conditions, we achieved 0.37 mM of vidarabine from 5 mM of sucrose and 2 mM of adenine, representing 18.7% of the theoretical yield. Furthermore, this biosystem also has the capability to produce other arabinosides, such as spongouridine, arabinofuranosylguanine, hypoxanthine arabinofuranoside, fludarabine, and 2-methoxyadenine arabinofuranoside, from sucrose, and corresponding nucleobase by introducing different nucleoside phosphorylases. Overall, our biosynthesis approach provides a pathway for the biosynthesis of arabinose-derived nucleoside analogs, offering potential applications in the pharmaceutical industry.

[Effects of Long-term Biochar Addition on Denitrification N2O Emissions from Bacteria and Fungi in Paddy Soil].

Denitrification driven by bacteria and fungi is the main source of nitrous oxide （N2O） emissions from paddy soil. It is generally believed that biochar reduces N2O emissions by influencing the bacterial denitrification process, but the relevant mechanism of its impact on fungal denitrification is still unclear. In this study, the long-term straw carbonization returning experimental field in Changshu Agricultural Ecological Experimental Base of the Chinese Academy of Sciences was taken as the object. Through indoor anaerobic culture and molecular biology technology, the relative contributions of bacteria and fungi to denitrifying N2O production in paddy soil and the related microorganism mechanism were studied under different long-term biochar application amounts （blank, 2.25 t·hm-2, and 22.5 t·hm-2, respectively, expressed by BC0, BC1, and BC10）. The results showed that compared with that in BC0, biochar treatment significantly reduced N2O emission rate, denitrification potential, and cumulative N2O emissions, and the contribution of bacterial denitrification was greater than that of fungal denitrification in all three treatments. Among them, the relative contribution rate of bacterial denitrification in BC10 （62.9%） was significantly increased compared to BC0 （50.8%）, whereas the relative contribution rate of fungal denitrification in BC10 （37.1%） was significantly lower than that in BC0 （49.2%）. The application of biochar significantly increased the abundance of bacterial denitrification functional genes （nirK, nirS, and nosZ） but reduced the abundance of fungal nirK genes. The contribution rate of fungal denitrification was significantly positively correlated with the N2O emission rate and negatively correlated with soil pH, TN, SOM, and DOC. Biochar may have inhibited the growth of denitrifying fungi by increasing pH and carbon and nitrogen content, reducing the abundance of related functional genes, thereby weakening the reduction ability of NO to N2O during fungal denitrification process. This significantly reduces the contribution rate of N2O production during the fungal denitrification process and the denitrification N2O emissions from paddy soil. This study helps to broaden our understanding of the denitrification process in paddy soil and provides a theoretical basis for further regulating fungal denitrification N2O emissions.

A predictive model to explore risk factors for severe COVID-19.

With the rapid spread of the novel coronavirus (COVID-19), a sustained global pandemic has emerged. Globally, the cumulative death toll is in the millions. The rising number of COVID-19 infections and deaths has severely impacted the lives of people worldwide, healthcare systems, and economic development. We conducted a retrospective analysis of the characteristics of COVID-19 patients. This analysis includes clinical features upon initial hospital admission, relevant laboratory test results, and imaging findings. We aimed to identify risk factors for severe illness and to construct a predictive model for assessing the risk of severe COVID-19. We collected and analyzed electronic medical records of confirmed COVID-19 patients admitted to the Affiliated Hospital of Jiangsu University (Zhenjiang, China) between December 18, 2022, and February 28, 2023. According to the WHO diagnostic criteria for the novel coronavirus, we divided the patients into two groups: severe and non-severe, and compared their clinical, laboratory, and imaging data. Logistic regression analysis, the least absolute shrinkage and selection operator (LASSO) regression, and receiver operating characteristic (ROC) curve analysis were used to identify the relevant risk factors for severe COVID-19 patients. Patients were divided into a training cohort and a validation cohort. A nomogram model was constructed using the "rms" package in R software. Among the 346 patients, the severe group exhibited significantly higher respiratory rates, breathlessness, altered consciousness, neutrophil-to-lymphocyte ratio (NLR), and lactate dehydrogenase (LDH) levels compared to the non-severe group. Imaging findings indicated that the severe group had a higher proportion of bilateral pulmonary inflammation and ground-glass opacities compared to the non-severe group. NLR and LDH were identified as independent risk factors for severe patients. The diagnostic performance was maximized when NLR, respiratory rate (RR), and LDH were combined. Based on the statistical analysis results, we developed a COVID-19 severity risk prediction model. The total score is calculated by adding up the scores for each of the twelve independent variables. By mapping the total score to the lowest scale, we can estimate the risk of COVID-19 severity. In addition, the calibration plots and DCA analysis showed that the nomogram had better discrimination power for predicting the severity of COVID-19. Our results showed that the development and validation of the predictive nomogram had good predictive value for severe COVID-19.

Biomarker of severity in hospitalised patients with COVID-19: a retrospective study.

BACKGROUND: The novel COVID-19 was rapidly spreading and was highly contagious. COVID-19 caused over 6 million deaths worldwide, with high mortality rates, particularly in severe cases. OBJECTIVE: This study aimed to investigate whether serum albumin-neutrophil count to lymphocyte count ratio (NLR) score (ANS) could be used as a prognostic indicator of COVID-19 severity. DESIGN: A retrospective study. PARTICIPANTS: Based on the WHO diagnostic criteria, patients were classified as either non-severe (n=270) or severe (n=100). PRIMARY AND SECONDARY OUTCOME MEASURES: NLR, serum albumin level and ANS. MAIN RESULTS: The NLR of patients with severe disease was significantly higher than that of those with non-severe disease. Serum albumin levels were significantly lower in patients with severe disease than in those with non-severe disease. The cut-off values representing the maximum potential effectiveness of serum albumin and NLR were 33.5 g/L and 8.25, respectively, according to the Youden index. In patients with severe COVID-19, we observed that the serum albumin level, NLR and ANS were independent prognostic indicators of severe COVID-19 using logistic analysis. The relative risk of severe COVID-19 was 7.65 (95% CI 3.72 to 15.75, p<0.05) in the ANS 2 group compared with that in ANS 0. CONCLUSIONS: ANS could be used as a prognostic indicator of COVID-19 severity.

External carbon source as a viable tool for controlling antibiotics and antibiotic resistance genes (ARGs) in effluent: Influence on antibiotic removal and ARGs dissemination.

Fluoroquinolone antibiotics and antibiotic resistance genes (ARGs) regarded as emerging contaminants were poorly removed in conventional wastewater treatment plants (WWTPs). Nitrogen-containing heterocyclic organics were found to be biodegraded through denitrification co-metabolism. The feasibility to enhance antibiotics removal efficiency in WWTPs through denitrification co-metabolism needs to be further verified. Meanwhile, due to significant correlation between ARGs profiles and nitrogen removal that was previously observed, the dissemination of ARGs during denitrification was worthy of in-depth understanding. Herein, the antibiotic removal and ARGs dissemination in denitrification co-metabolism condition were investigated with different denitrifying consortiums that acclimated under different conditions in terms of carbon source and the exposure of Ofloxacin (OFL). The results suggest that the removal of OFL can be enhanced by the denitrification co-metabolism. The tolerance to OFL is different among various denitrifying communities. For the denitrifying consortiums acclimated with methanol, long-term exposure to trace OFL (1 µg/L) could reduce the capabilities of removal and tolerance to OFL. On the contrary, those acclimated with sodium acetate (NaAc), the capabilities of removal and tolerance to OFL, were enhanced by long-term exposure to trace OFL. According to the quantitative determination to 384 target genes with high-throughput quantitative PCR, the abundance of ARGs in consortiums greatly increased when exposed to OFL at the concentration of comparable to sewage, which was also much larger than that acclimated with methanol. It can be confirmed and supported by DNA sequencing results that the antibiotic removal and the dissemination of ARGs were determined by microbial community that could be shaped with carbon source. These conclusions suggest that selecting the right external carbon source can be a useful strategy for WWTPs to control antibiotics and ARGs in the effluent. From a new perspective on mitigating ARGs dissemination, NaAc was not an appropriate carbon source.

Unraveling how Fe-Mn modified biochar mitigates sulfamonomethoxine in soil water: The activated biodegradation and hydroxyl radicals formation.

This study indicated that the application of a novel Fe-Mn modified rice straw biochar (Fe/Mn-RS) as soil amendment facilitated the removal of sulfamonomethoxine (SMM) in soil water microcosms, primarily via activating degradation mechanism rather than adsorption. The similar enhancement on SMM removal did not occur using rice straw biochar (RS). Comparison of Fe/Mn-RS with RS showed that Fe/Mn-RS gains new physic-chemical properties such as abundant oxygenated C-centered persistent free radicals (PFRs). In the Fe/Mn-RS microcosms, the degradation contributed 79.5-83.8% of the total SMM removal, which was 1.28-1.70 times higher than that in the RS microcosms. Incubation experiments using sterilized and non-sterilized microcosms further revealed that Fe/Mn-RS triggered both the biodegradation and abiotic degradation of SMM. For abiotic degradation of SMM, the abundant •OH generation, induced by Fe/Mn-RS, was demonstrated to be the major contributor, according to EPR spectroscopy and free radical quenching experiments. Fenton-like bio-reaction occurred in this process where Fe (Ⅲ), Mn (Ⅲ) and Mn (Ⅳ) gained electrons, resulting in oxidative hydroxylation of SMM. This work provides new insights into the impacts of biochar on the fates of antibiotics in soil water and a potential solution for preventing antibiotic residues in agricultural soil becoming a non-point source pollutant.

Attenuation of Epileptogenesis and Cognitive Deficits by a Selective and Potent Kv7 Channel Opener in Rodent Models of Seizures.

Targeting neuronal Kv7 channels by pharmacological activation has been proven to be an attractive therapeutic strategy for epilepsy. Here, we show that activation of Kv7 channels by an opener SCR2682 dose-dependently reduces seizure activity and severity in rodent models of epilepsy induced by a GABAa receptor antagonist pentylenetetrazole (PTZ), maximal electroshock, and a glutamate receptor agonist kainic acid (KA). Electroencephalographic recordings of rat cerebral cortex confirm that SCR2682 also decreases epileptiform discharges in KA-induced seizures. Nissl and neuronal nuclei staining further demonstrates that SCR2682 also protects neurons from injury induced by KA. In Morris water maze navigation and Y-maze tests, SCR2682 improves PTZ- and KA-induced cognitive impairment. Taken together, our findings demonstrate that pharmacological activation of Kv7 by novel opener SCR2682 may hold promise for therapy of epilepsy with cognitive impairment. SIGNIFICANCE STATEMENT: A neuronal Kv7 channel opener SCR2682 attenuates epileptogenesis and seizure-induced cognitive impairment in rodent models of seizures, thus possessing a developmental potential for effective therapy of epilepsy with cognitive impairment.

Deciphering physicochemical properties and enhanced microbial electron transfer capacity by magnetic biochar.

Magnetic biochar is important for improving the electron transfer capacity (ETC) of microorganisms in wastewater treatment. In this study, three magnetic biochar under different pyrolysis temperatures (300, 500 and 700 °C) were prepared by co-precipitation, and their characteristics and impacts on mediating microbial ETC were investigated. Results indicated that magnetic biochar had a higher capacitance and conductivity than pyrolytic biochar, with the largest specific capacitance of 14.7F/g for FCS700 (magnetic biochar prepared at 700 °C). The addition of magnetic biochar could improve the nitrogen removal efficiency of a sludge-biochar system. The electron transfer resistance (Rct) of magnetic biochar was lower than pyrolytic biochar by 25.5 % (300 °C), 19.7 % (500 °C), and 11.6 % (700 °C), respectively. The structure of the microbial community in the sludge-biochar system differed significantly. Spearman correlation suggested that the electrochemical properties of biochar were an important factor affecting the structure of the microbial community.

p53/sirtuin 1/NF-κB Signaling Axis in Chronic Inflammation and Maladaptive Kidney Repair After Cisplatin Nephrotoxicity.

Chronic inflammation contributes to maladaptive kidney repair, but its regulation is unclear. Here, we report that sirtuin 1 (SIRT1) is downregulated after repeated low-dose cisplatin (RLDC) injury, and this downregulation leads to p65 acetylation and consequent NF-κB activation resulting in a persistent inflammatory response. RLDC induced the down-regulation of SIRT1 and activation of NF-κB, which were accompanied by chronic tubular damage, tubulointerstitial inflammation, and fibrosis in mice. Inhibition of NF-κB suppressed the production of pro-inflammatory cytokines and fibrotic phenotypes in RLDC-treated renal tubular cells. SIRT1 activation by its agonists markedly reduced the acetylation of p65 (a key component of NF-κB), resulting in the attenuation of the inflammatory and fibrotic responses. Conversely, knockdown of SIRT1 exacerbated these cellular changes. At the upstream, p53 was activated after RLDC treatment to repress SIRT1, resulting in p65 acetylation, NF-κB activation and transcription of inflammatory cytokines. In mice, SIRT1 agonists attenuated RLDC-induced chronic inflammation, tissue damage, and renal fibrosis. Together, these results unveil the p53/SIRT1/NF-κB signaling axis in maladaptive kidney repair following RLDC treatment, where p53 represses SIRT1 to increase p65 acetylation for NF-κB activation, leading to chronic renal inflammation.

A phosphite-based screening platform for identification of enzymes favoring nonnatural cofactors.

Enzymes with dedicated cofactor preference are essential for advanced biocatalysis and biomanufacturing, especially when employing nonnatural nicotinamide cofactors in redox reactions. However, directed evolution of an enzyme to switch its cofactor preference is often hindered by the lack of efficient and affordable method for screening as the cofactor per se or the substrate can be prohibitively expensive. Here, we developed a growth-based selection platform to identify nonnatural cofactor-dependent oxidoreductase mutants. The growth of bacteria depended on the nicotinamide cytosine dinucleotide (NCD) mediated conversion of non-metabolizable phosphite into phosphate. The strain BW14329 lacking the ability to oxidize phosphite was suitable as host, and NCD-dependent phosphite dehydrogenase (Pdh*) is essential to the selection platform. Previously confirmed NCD synthetase with NCD synthesis capacity and NCD-dependent malic enzyme were successfully identified by using the platform. The feasibility of this strategy was successfully demonstrated using derived NCD-active malic enzyme as well as for the directed evolution of NCD synthetase in Escherichia coli. A phosphite-based screening platform was built for identification of enzymes favoring nonnatural cofactor NCD. In the future, once Pdh variants favoring other biomimetic or nonnatural cofactors are available this selection platform may be readily redesigned to attain new enzyme variants with anticipated cofactor preference, providing opportunities to further expand the chemical space of redox cofactors in chemical biology and synthetic biology.

Afterglow-Suppressed Lu2O3:Eu3+ Nanoscintillators for High-Resolution and Dynamic Digital Radiographic Imaging.

Lu2(1-x)Eu2xO3 nanoscintillators (x = 0.005, 0.01, 0.03, 0.05, 0.07, and 0.10) with red emission were synthesized by a coprecipitation method. It is found that their photo- and radioluminescence intensities increase with increasing Eu3+ concentration until x = 0.05. According to their concentration-dependent luminescence intensity ratios (I610(C2)/I582(S6)), the existing energy transfer from Eu3+(S6) (occupying S6 sites) to Eu3+(C2) (occupying C2 sites) can be confirmed. Based on the spectral data and density functional theory (DFT) calculations, the origin of Lu2O3:Eu3+ persistent luminescence at low concentration might be related to the tunneling processes between Eu3+ (occupying C2 and S6 sites) and oxygen interstitials (Oi×). After dispersing afterglow-suppressed Lu2O3:Eu3+ nanoscintillators into polymethyl methacrylate (PMMA) polymer-acetone solution, flexible PMMA-Lu2O3:Eu3+ composite films with high thermal stability and radiation resistance were fabricated by a doctor blade method. As the flexible composite film was used as an imaging plate, static X-ray images with high spatial resolution (5.5 lp/mm) under an extremely low dose of ∼1.1 µGyair can be acquired. When a watch with a moving second hand was used as an object, the dynamic X-ray imaging can be realized under a dose rate of 55 µGyair·s-1. Our results demonstrate that Lu2O3:Eu3+ nanoscintillators can be regarded as candidate materials for dynamic digital radiographic imaging.

[Effects of biochar combined with nitrification/urease inhibitors on soil active nitrogen emissions from subtropical paddy soils]. / ç”Ÿç‰©ç‚­é æ–½ç¡åŒ–/è„²é ¶æŠ‘åˆ¶å‰‚å¯¹äºšçƒ­å¸¦æ°´ç¨»åœŸæ´»æ€§æ°®æ°”ä½“æŽ’æ”¾çš„å½±å“.

We examined the effects of biochar and urease inhibitors/nitrification inhibitors on nitrification process, ammonia and N2O emission in subtropical soil, and determined the best combination of biochar with nitrification and urease inhibitors. This work could provide a theoretical basis for the mitigation of the negative environmental risk caused by reactive nitrogen gas in the application of nitrogen fertilizer. A indoor aerobic culture test was conducted with seven treatments [urea+biochar (NB), urea+nitrification inhibitor (N+NI), urea+urease inhibitor (N+UI), urea+nitrification inhibitor+urease inhibitor (N+NIUI), urea+nitrification inhibitor+biochar (NB+NI), urea+urease inhibitor+biochar (NB+UI), urea+nitrification inhibitor+urease inhibitor+biochar (NB+NIUI)] and urea (N) as the control. The dynamics of soil inorganic nitrogen content, N2O emission and the volatility of ammonia volatilization were observed under combined application of biochar with urease inhibitor (NBPT)/nitrification inhibitor (DMPP). The results showed that:1)Compared to the control (5.11 mg N·kg-1·d-1) during the incubation period, NB treatment significantly increased therate constant of nitrification by 33.9%, and N+NI treatment significantly reduced the nitrification rate constant by 22.9%. NB treatment significantly increased the abundance of ammonia oxidizing bacteria (AOB) by 56.0%. 2) Compared with N treatment, N+NI and NB+NI treatments signi-ficantly enhanced the cumulative emission of NH3 by 49%. The N+UI treatment reduced the cumulative loss of NH3. The inhibition effect of NB+UI treatment was more significant. 3) The emission rate of N2O was highest in the first 10 days after fertilization. The N2O emission under NB treatment was the earliest, and that of N treatment was the highest (5.87 µg·kg-1·h-1). The combined application of DMPP and NBPT performed the best in reducing soil N2O emission. We estimated global warming potential (GWP) of the direct N2O and indirect N2O (NH3) emissions. Compared with N treatments, N+NI and NB+NI treatments increased the GWP by 34.8% and 40.9%, respectively. While the NB and NB+UI treatments significantly reduced the GWP by 45.9% and 60.5%, the combination of biochar and urease inhibitor had the best effect on reduction of GWP of soil active nitrogen emissions.

The Molecular Mechanism of Propylene Glycol Monocaprylate on Skin Retention: Probing the Dual Roles on the Molecular Mobility and Collagen Connection in Roflumilast Cream.

The present work was to construct a roflumilast (ROF) cream for the treatment of psoriasis and clarify the dual roles of propylene glycol monocaprylate (PGM) in both molecular mobility of the cream, and drug-skin miscibility via drug-PGM-ceramide and drug-PGM-collagen intermolecular interaction. The cream formulation was screened through the stability study and in vitro skin administration study, optimized by Plackett-Burman and Box-Behnken design, and finally verified by the in vivo tissue distribution study. PGM demonstrated a significant drug skin retention enhancement effect (Rmax in vivo = 19.5 µg/g). It increased the molecular mobility of the oil phase of the cream by decreasing the molecular interaction of oil molecules proven by the rheology study (Ec = 3.73 × 10-4 mJ·m-3). More importantly, because of the good stratum corneum (SC) compatibility (∆H = - 403.88 J/g), PGM promoted an orderly flow of SC lipids (X-ray scattering, ΔLPP = 1.18 nm) and entered the viable epidermis/dermis (VE/DE) in large quantities (RPGM = 1186 µg/g), acting as a bridge to connect the drug to collagen through two H-bonds (LengthH-bond = 2.846 Å and 3.313 Å), thus increasing the miscibility of drug and VE/DE significantly (∆H = - 310.10 J/g, Emix = 21.66 kcal/mol). In this study, a ROF cream was developed successfully and the effect of PGM on the skin retention was clarified at molecular level.

Photothermal conversion performance and acid-induced aggregation of PLNP-Bi2S3 composite nanoplatforms.

Poly(sodium 4-styrenesulfonate) (PSS) molecule modified PLNP-Bi2S3 composite nanoplatforms were constructed by using polyvinylpyrrolidone (PVP) modified Bi2S3 nanoparticles (∼4.6 nm) as a photothermal agent and hexadecyl trimethyl ammonium bromide (CTAB) coated Zn2Ga2.98Ge0.75O8:Cr0.023+ (ZGGO:Cr3+@CTAB) persistent luminescence nanoparticles (PLNPs) through electrostatic adsorption. It is found that the above composite nanoplatforms have excellent laser-irradiation thermal stability and good photothermal conversion performance. The measured photothermal conversion efficiency is ∼44%, which is higher than that (∼37%) of the PLNP-GNR (gold nanorod) composite nanoplatforms. Meanwhile, PSS modified PLNP-Bi2S3 composite nanoplatforms exhibited good solution dispersibility in blood and normal tissue environments. While reaching tumor sites, the above composite nanoplatforms can be rapidly accumulated in cancer cells with acidic environments. This pH-responsive acid-induced aggregation can be ascribed to the chemical reaction induced by the protonation of PSS modified PLNP-Bi2S3 composite nanoplatforms with a negatively charged surface in the acidic environments. Our results suggest that PSS modified PLNP-Bi2S3 composite nanoplatforms might be applied to precision diagnosis and therapy of deep-tissue tumors.

Engineering Formaldehyde Dehydrogenase from Pseudomonas putida to Favor Nicotinamide Cytosine Dinucleotide.

The enzyme formaldehyde dehydrogenase (FalDH) from Pseudomonas putida is of particular interest for biotechnological applications as it catalyzes the oxidation of formaldehyde independent of glutathione. However, the consumption of a stoichiometric amount of nicotinamide adenine dinucleotide (NAD) can be challenging at the metabolic level as this may affect many other NAD-linked processes. A potential solution is to engineer FalDH to utilize non-natural cofactors. Here we devised FalDH variants to favor nicotinamide cytosine dinucleotide (NCD) by structure-guided modification of the binding pocket for the adenine moiety of NAD. Several mutants were obtained and the best one FalDH 9B2 had over 150-fold higher preference for NCD than NAD. Molecular docking analysis indicated that the cofactor binding pocket shrunk to better fit NCD, a smaller-sized cofactor. FalDH 9B2 together with other NCD-linked enzymes offer opportunities to assemble orthogonal pathways for biological conversion of C1 molecules.

Biochar mitigated more N-related global warming potential in rice season than that in wheat season: An investigation from ten-year biochar-amended rice-wheat cropping system of China.

Rice-wheat cropping system (RWCS), the major rice-based cropping system, constitutes a significant source of N-related greenhouse gas (GHG) emission due to the unique wet-dry alternation process. Biochar is often highlighted as a potential solution for reducing fertilizer N losses, hence, understanding its effects on Ngr emissions (mainly NH3 and N2O) under wet-dry conditions is critical to inform strategies for GHG mitigation. This study investigated the responses of NH3 and N2O emissions to biochar amendments during rice and wheat seasons based on in situ measurements under ten-year successive straw biochar application in RWCS. Our results indicated that 43.7% and 89.9% of N2O and NH3 emissions were emitted during rice season and 56.3% and 10.1% during wheat season, respectively. Long-term biochar amendment was found to play significant role in mitigating NH3 emissions (38.6-43.9%), which could be attributed to the disappearance of liming effect of aged-biochar on flooding water and decreased NH4+ concentrations in the soil. However, considerable variation of N2O emissions were observed in RWCS. Biochar showed a significant decreasing effect on the net global warming potential related to N2O and NH3 emissions (GWPN) in rice season (16.1-89.6%), and slight increased tendency in wheat season (1.43-13.1%) primarily due to its positive effects on N2O emission. Biochar amendment mainly BC22.5, significantly increased above-ground yields by 9.22% in rice season. Thus, it is a low carbon-producing and sustainable crop management method that can support crop production, C sequestration, and GHG mitigation in rice season under RWCS from the viewpoint of the Ngr mitigation. Our results suggest that emission patterns of N2O and NH3 varied with wet-dry alternation under the disturbance of long-term biochar amendment in RWCS; moreover, long-term biochar application exhibited significant potential for mitigating soil Ngr losses in rice season for RWCS.

Effect of the combination of permeation enhancer and ion-pairs strategies on transdermal delivery of tofacitinib.

The aim of the present study was to develop a tofacitinib (TOF) transdermal patch by the combination of ion-pairs and chemical permeation enhancer strategies. And a theory of controlled release of chemical permeation enhancers by counterion was proposed on the basis of in vitro skin permeation and skin retention study. Through the in vitro skin permeation study, the formulation factors such as counterion, pressure sensitive adhesive (PSA), drug loading and patch thickness were investigated, and the optimized patch (6.5% LA-TOF, 15% POCC and thickness = 50 µm) was evaluated by the pharmacokinetic study. The AUC0-t of the optimized patch was 529.89 ± 45 h ng/mL. Special attention has been paid to the molecular mechanism of the effects of counterion concentration on the release and permeation enhancement effect of penetration enhancer. FTIR study, 13C NMR, XPS and molecular modeling were conducted to investigate the molecular interaction between POCC and LA. Raman Imaging and ATR-FTIR were used to explore the POCC content in the skin and the interference degree to lipid. The results revealed that a strong hydrogen bond appeared between LA and the hydroxyl group of POCC, which inhibited the release of POCC, thus reducing the lipid disturbance and permeation enhancement effect of POCC. In conclusion, this TOF patch was successfully developed. The effect of counterion on permeation enhancers was clarified at molecular level, and these results provided references for the development of TOF patch.

Radiofrequency thermocoagulation combined with doxorubicin injection for treatment of trigeminal neuralgia mandibular branch.

OBJECTIVES: This study aimed to evaluate the clinical application value of 3D printed template-guided radiofrequency thermocoagulation combined with doxorubicin injection for the treatment of trigeminal neuralgia mandibular branch. METHODS: A total of 50 patients with primary trigeminal neuralgia mandibular branch in the hospital from January 2019 to September 2020 were randomly divided into two groups: 3D printed template-guided radiofrequency thermocoagulation combined with doxorubicin injection was used as the research group (n=25), and 3D printed template guided radiofrequency thermocoagulation was used as the control group (n=25). Comparative analysis of visual analogue score (VAS) was conducted before and immediately after surgery and at 1, 3, 6, and 12 months after surgery. The Brisman efficacy evaluation criteria for trigeminal neuralgia was used to evaluate the therapeutic effect of each postoperative follow-up period, and postoperative complications were observed. RESULTS: The VAS immediately after surgery and at 1, 3, 6, and 12 months after surgery in the two groups was significantly lower than that before surgery, with statistical significance (P<0.05). According to Brisman efficacy evaluation criteria for trigeminal neuralgia, no significant difference was found in the efficacy between the two groups at 1 and 3 months after surgery (P>0.05). At 6 and 12 months postoperatively, the effectiveness of the research group was higher than that of the control group, and the differences were statistically significant (P<0.05). In the research group, no recurrence occurred during the follow-up period, whereas in the control group, one, two, and four recurrences occurred 3, 6, and 12 months after surgery, respectively. No obvious complications were found in both groups. CONCLUSIONS: 3D printed template-guided radiofrequency thermocoagulation combined with doxorubicin injection for the treatment of trigeminal neuralgia mandibular branch could enhance the long-term curative effect and reduce the recurrence rate, thus worthy of clinical promotion and application.

Manipulating fatty-acid profile at unit chain-length resolution in the model industrial oleaginous microalgae Nannochloropsis.

The chain length (CL) of fatty acids (FAs) is pivotal to oil property, yet to what extent it can be customized in industrial oleaginous microalgae is unknown. In Nannochloropsis oceanica, to modulate long-chain FAs (LCFAs), we first discovered a fungi/bacteria-originated polyketide synthase (PKS) system which involves a cytoplasmic acyl-ACP thioesterase (NoTE1). NoTE1 hydrolyzes C16:0-, C16:1- and C18:1-ACP in vitro and thus intercepts the specific acyl-ACPs elongated by PKS for polyunsaturated FA biosynthesis, resulting in elevation of C16/C18 monounsaturated FAs when overproduced and increase of C20 when knocked out. For medium-chain FAs (MCFAs; C8-C14), C8:0 and C10:0 FAs are boosted by introducing a Cuphea palustris acyl-ACP TE (CpTE), whereas C12:0 elevated by rationally engineering CpTE enzyme's substrate-binding pocket to shift its CL preference towards C12:0. A mechanistic model exploiting both native and engineered PKS and type II FAS pathways was thus proposed for manipulation of carbon distribution among FAs of various CL. The ability to tailor FA profile at the unit CL resolution from C8 to C20 in Nannochloropsis spp. lays the foundation for scalable production of designer lipids via industrial oleaginous microalgae.

Structural Insights into Malic Enzyme Variants Favoring an Unnatural Redox Cofactor.

The use of nicotinamide cytosine dinucleotide (NCD), a biocompatible nicotinamide adenosine dinucleotide (NAD) analogue, is of great scientific and biotechnological interest. Several redox enzymes have been devised to favor NCD, and have been successfully applied in creating NCD-dependent redox systems. However, molecular interactions between cofactor and protein have still to be disclosed in order to guide further engineering efforts. Here we report the structural analysis of an NCD-favoring malic enzyme (ME) variant derived from Escherichia coli. The X-ray crystal structure data revealed that the residues located at position 346 and 401 in ME acted as the "gatekeepers" of the adenine moiety binding cavity. When Arg346 was substituted with either acidic or aromatic residues, the corresponding mutants showed substantially reduced NCD preference. Inspired by these observations, we generated Lactobacillus helveticus derived d-lactate dehydrogenase variants at Ile177, the counterpart to Arg346 in ME, and found a similar trend in terms of cofactor preference changes. As many NAD-dependent oxidoreductases share key structural features, our results provide guidance for protein engineering to obtain more NCD-favoring variants.