Structural characterization of the Plasmodium falciparum lactate transporter PfFNT alone and in complex with antimalarial compound MMV007839 reveals its inhibition mechanism.

Plasmodium falciparum, the deadliest causal agent of malaria, caused more than half of the 229 million malaria cases worldwide in 2019. The emergence and spreading of frontline drug-resistant Plasmodium strains are challenging to overcome in the battle against malaria and raise urgent demands for novel antimalarial agents. The P. falciparum formate-nitrite transporter (PfFNT) is a potential drug target due to its housekeeping role in lactate efflux during the intraerythrocytic stage. Targeting PfFNT, MMV007839 was identified as a lead compound that kills parasites at submicromolar concentrations. Here, we present 2 cryogenic-electron microscopy (cryo-EM) structures of PfFNT, one with the protein in its apo form and one with it in complex with MMV007839, both at 2.3 Å resolution. Benefiting from the high-resolution structures, our study provides the molecular basis for both the lactate transport of PfFNT and the inhibition mechanism of MMV007839, which facilitates further antimalarial drug design.

Epidemiology of Vancomycin in Combination With Piperacillin/Tazobactam-Associated Acute Kidney Injury in Children: A Systematic Review and Meta-analysis.

BACKGROUND: Several studies have shown that vancomycin combined with piperacillin/tazobactam (VPT) increased the risk of acute kidney injury (AKI) compared with other antibiotics in children. However, the epidemiology of VPT-associated AKI in children is unknown. OBJECTIVE: To evaluate the incidence and risk factors of VPT-associated AKI in children. DATA SOURCES: Literature databases of PubMed, Embase, Cochrane Library, China National Knowledge Infrastructure (CNKI), VIP Database, WanFang Database, and China Biology Medicine Disc were searched from inception to November 2023. References of included studies were also manually checked. STUDY SELECTION AND DATA EXTRACTION: Two independent reviewers selected studies, extracted data, and quality assessment. Meta-analyses were performed to quantify the incidence and risk factors of VPT-associated AKI in children. DATA SYNTHESIS: Sixteen cohort studies were identified. Overall, the incidence of VPT-associated AKI in children was 24.3% (95% CI: 17.9%-30.6%). The incidence of VPT-associated AKI in critically ill children (26.6%) was higher than that in noncritically ill children (10.9%). Moreover, higher serum vancomycin trough concentration (>15 mg/L), use of vasopressors, combination of nephrotoxins and intensive care unit admission were risk factors for VPT-associated AKI in children (P < 0.05). RELEVANCE TO PATIENT CARE AND CLINICAL PRACTICE: Identifying high-risk groups and determining safer treatments is critical to reducing the incidence of VPT-associated AKI in children. CONCLUSIONS: The incidence of VPT-associated AKI in children is high, especially in critically ill children. Medication regimens should be personalized based on the presence of individual risk factors. Moreover, renal function was regularly assessed throughout treatment with VPT.

The reference range of lamotrigine in the treatment of epilepsy in children: a systematic review.

PURPOSE: This study intends to assess the reference range of lamotrigine concentration for treating childhood epilepsy. METHODS: PubMed, Ovid-Embase, The Cochrane Library, CNKI, WanFang data and VIP databases were searched from database inception to January 2022. RCT, cohort study, case-control study, cross-sectional study that estimated the reference range of lamotrigine for children epilepsy treatment were included. The data extracted included basic information, statistical methods, data type, and results of reference range. Descriptive analysis was performed for them. RESULTS: 8 studies were included and estimated the reference range, and all of them were calculated based on efficacy data and/or concentration data. Statistical methods including ROC curve, concentration-effect curve, mean ± standard deviation, 95% confidence interval and percentile interval were utilized. For lamotrigine monotherapy, the lower limits ranged from 2.06 mg/L to 3.99 mg/L, and the upper limits ranged from 8.43 mg/L to 9.08 mg/L, showing basic consistency. However, for lamotrigine concomitant with valproate, the lower limits ranged from 2.00 mg/L to 8.00 mg/L, and the upper limit was 11.50 mg/L, for lamotrigine concomitant with other antiepileptics, the lower limits ranged from 1.00 mg/L to 3.09 mg/L, and the upper limits varied from 5.90 mg/L to 16.24 mg/L, indicating inconsistency. CONCLUSION: Several studies have estimated the reference range of lamotrigine for childhood epilepsy, while controversy exist and no studies have determined the upper limit of the range based on safety data. To establish the optimal reference range, further high-quality studies are necessary that consider both efficacy and safety data.

Incidence and risk factors of drug-induced kidney injury in children: a systematic review and meta-analysis.

PURPOSE: To comprehensively summarize the incidence and risk factors of drug-induced kidney injury (DIKI) in children. METHODS: We systematically searched seven databases from inception to November 2022. Two independent reviewers selected studies, extracted data, and assessed the risk of bias. Meta-analyses were conducted to quantify the incidence and risk factors of DIKI in children. RESULTS: A total of 69 studies comprising 195,894 pediatric patients were included. Overall, the incidence of DIKI in children was 18.2% (95%CI: 16.4%-20.1%). The incidence of DIKI in critically ill children (19.6%, 95%CI: 15.9%-23.3%) was higher than that in non-critically ill children (16.1%, 95%CI: 12.9%-19.4%). Moreover, the risk factors for DIKI in children were intensive care unit (ICU) admission (OR = 1.59, 95% CI: 1.42-1.78, P = 0.000), treatment days (OR = 1.04, 95% CI: 1.03-1.05, P = 0.000), surgical intervention (OR = 1.43, 95% CI: 1.00-2.02, P = 0.048), infection (OR = 2.30, 95% CI: 1.44-3.66, P = 0.000), patent ductus arteriosus (OR = 4.78, 95% CI: 1.82-12.57, P = 0.002), chronic kidney disease (OR = 2.78, 95% CI: 1.92-4.02, P = 0.000), combination with antibacterial agents (OR = 1.98, 95% CI: 1.54-2.55, P = 0.000), diuretics (OR = 1.97, 95% CI: 1.51-2.56, P = 0.000), combination with antiviral agents (OR = 1.50, 95% CI: 1.11-2.04, P = 0.008), combination with non-steroidal anti-inflammatory drugs (OR = 1.79, 95% CI: 1.40-2.28, P = 0.000), and combination with immunosuppressive agents (OR = 2.84, 95% CI: 1.47-5.47, P = 0.002). CONCLUSION: The incidence of DIKI in children is high, especially in critically ill children. Identifying high-risk groups and determining safer treatments is critical to reducing the incidence of DIKI in children. In clinical practice, clinicians should adjust medication regimens for high-risk pediatric groups, such as ICU admission, some underlying diseases, combination with nephrotoxic drugs, etc., and regularly evaluate kidney function throughout treatment.

Drug-associated kidney injury in children: a disproportionality analysis of the FDA Adverse Event Reporting System.

Drug-associated kidney injury is related to longer hospitalization and increased risk of chronic kidney disease and mortality. However, there is currently a lack of large population studies on drug-associated kidney injury in children. This study aimed to study perform data mining to generate hypotheses on drugs, which may deserve to be assessed as per their potential risk of increasing kidney injury in children. We extracted and analyzed reports on drugs associated with kidney injury in children in the FDA Adverse Event Reporting System (FAERS). We conducted a disproportionality analysis using proportional reporting ratio (PRR) to evaluate the association between drugs and kidney injury in children. Meanwhile, comparisons were performed with drug labels to identify drugs that, despite not having kidney injury currently mentioned in their labels, may potentially be associated with risks of kidney injury in children. A total of 6347 children had drug-associated kidney injury in the FAERS database. The top five drugs with the highest PRR were gentamicin (PRR = 12.28, N = 157 cases, Chi-Squared = 1602.77), piperacillin-tazobactam (PRR = 9.77, N = 129 cases, Chi-Squared = 1003.24), amlodipine (PRR = 8.98, N = 271 cases, Chi-Squared = 1861.46), vancomycin (PRR = 8.91, N = 295 cases, Chi-Squared = 1998.64), and ceftriaxone (PRR = 8.00, N = 251 cases, Chi-Squared = 1494.02). According to drug labels, 9 drugs (9/30) were classified as potential nephrotoxins. CONCLUSIONS: Approximately one-third of drugs associated with kidney injury in children do not list kidney injury as a side effect in their drug labels. Future studies are therefore warranted to evaluate whether these drugs are associated with such a risk. WHAT IS KNOWN: • Nephrotoxic drugs are an increasingly common cause of acute kidney injury in hospitalized children. • Currently, no study has systematically combed drugs associated with kidney injury in children. WHAT IS NEW: • Approximately a third of drugs showing signals for potential kidney injury in children in data mining do not mention this side effect in their drug labels. • This study provides data on drugs needing further study to determine whether they might increase the risk of kidney injury in children.

Global, regional and national availability of essential medicines for children, 2009-2020: a systematic review and meta-analysis.

BACKGROUND: Access to essential medicines is a vital component of universal health coverage. The low availability of essential medicines for children (EMC) has led the World Health Organization (WHO) to issue a number of resolutions calling on member states on its improvement. But its global progress has been unclear. We aimed to systematically evaluate the progress of availability of EMC over the past decade across economic regions and countries. METHODS: We searched eight databases from inception to December 2021 and reference lists to identify included studies. Two reviewers independently conducted literature screening, data extraction and quality evaluation. This study was registered with PROSPERO, CRD42022314003. RESULTS: Overall, 22 cross-sectional studies covering 17 countries, 4 income groups were included. Globally, the average availability rates of EMC were 39.0% (95%CI: 35.5-42.5%) in 2009-2015 and 43.1% (95%CI: 40.1-46.2%) in 2016-2020. Based on the World Bank classification of economic regions, income was not proportional to availability. Nationally, the availability rate of EMC was reasonable and high (> 50%) in only 4 countries, and low or very low for the rest 13 countries. The availability rates of EMC in primary healthcare centers had increased, while that for other levels of hospitals slightly declined. The availability of original medicines decreased while that of generic medicines was stable. All drug categories had not achieved the high availability rate. CONCLUSION: The availability rate of EMC was low globally, with slight increase in the last decade. Continuous monitoring and timely reporting of the availability of EMC are also needed to facilitate targets setting and inform relevant policy making.

Comparison of the effects of ketamine via nebulization versus different pharmacological approaches in pediatric sedation: a systematic review and meta-analysis of randomized controlled trials.

BACKGROUND: Nebulized drug delivery is commonly used in pediatric clinical practice. The growing number of literatures have reported the application of nebulized ketamine in pediatric sedation in recent years. This meta-analysis of randomized controlled trials comparing the efficacy and safety of nebulized ketamine versus different pharmacological approaches was conducted to estimate the effects of this technique in pediatric sedation. METHODS: We searched PubMed, Embase, and Cochrane Library from inception to Feb 2023. All randomized controlled trials used nebulized ketamine as presurgical and pre-procedural sedatives in children were included. Sedative effects and various adverse events were considered as the outcomes. RESULTS: Ten studies with 727 pediatric patients were enrolled. Compared to nebulized dexmedetomidine, using of ketamine via nebulization showed similar sedation satisfaction (54.79% vs. 60.69%, RR = 0.88, with 95%CI [0.61, 1.27]), success rate of parental separation (57.27% vs. 73.64%, RR = 0.81, with 95%CI [0.61, 1.08]), and mask acceptability (37.27% vs. 52.73%, RR = 0.71, with 95%CI [0.45, 1.10]). However, the using of combination of two medications (nebulized ketamine plus nebulized dexmedetomidine) was associated with better sedative satisfaction (33.82% vs. 68.11%, RR = 0.50, with 95%CI [0.27, 0.92]) and more satisfactory mask acceptance (45.59% vs. 71.01%, RR = 0.69, with 95%CI [0.56, 0.86]). Compared with nebulized ketamine, using of nebulized dexmedetomidine was associated with less incidence of emergence agitation (18.18% vs. 3.33%, RR = 4.98, with 95%CI [1.88, 13.16]). CONCLUSIONS: Based on current evidences, compared to nebulized dexmedetomidine, nebulized ketamine provides inconspicuous advantages in pediatric sedation, and it has a relatively high incidence of emergence agitation. Combination of nebulized ketamine and dexmedetomidine might be considered as one preferred option in pediatric sedation as it can provide more satisfactory sedative effects. However, there is insufficient evidence regarding nebulized ketamine versus ketamine administered through other routes and nebulized ketamine versus other sedatives. The overall low or moderate quality of evidence evaluated by the GRADE system also calls for more high-quality studies with larger sample sizes in future. RESEARCH REGISTRATION: The protocol of present study was registered with PROSPERO (CRD42023403226).

Palladium-Catalyzed Inverse and Normal Dehydrogenative Aza-Morita-Baylis-Hillman Reactions with γ,δ-Unsaturated Compounds.

σ-Lewis base-catalyzed regio- and enantioselective aza-Morita-Baylis-Hillman (MBH) reaction of α,ß,γ,δ-unsaturated systems remains a challenge due to the intrinsic covalent activation mode. Here we demonstrate that a Pd0 complex can mediate the dehydrogenative reaction of γ,δ-unsaturated compounds to give corresponding electron-poor dienes, which further undergo δ-regioselective umpolung Friedel-Crafts-type addition to imines via auto-tandem Pd0 -π-Lewis base catalysis. After ß-H elimination of in situ formed PdII -complexes, unprecedented and chemically inverse aza-MBH-type adducts are finally furnished with fair to outstanding enantioselectivity, and a diversity of functional groups and both ketimine and aldimine acceptors can be well tolerated. Moreover, switchable α-regioselective normal aza-MBH-type reaction also can be realized by tuning catalytic conditions, whereas moderate to good enantioselectivity with low to excellent Z/E-selectivity is attained.

An Enzymatic Platform for Primary Amination of 1-Aryl-2-alkyl Alkynes.

Propargyl amines are versatile synthetic intermediates with numerous applications in the pharmaceutical industry. An attractive strategy for efficient preparation of these compounds is nitrene propargylic C(sp3)-H insertion. However, achieving this reaction with good chemo-, regio-, and enantioselective control has proven to be challenging. Here, we report an enzymatic platform for the enantioselective propargylic amination of alkynes using a hydroxylamine derivative as the nitrene precursor. Cytochrome P450 variant PA-G8 catalyzing this transformation was identified after eight rounds of directed evolution. A variety of 1-aryl-2-alkyl alkynes are accepted by PA-G8, including those bearing heteroaromatic rings. This biocatalytic process is efficient and selective (up to 2610 total turnover number (TTN) and 96% ee) and can be performed on preparative scale.

Efficacy and safety of intranasal midazolam versus intranasal ketamine as sedative premedication in pediatric patients: a meta-analysis of randomized controlled trials.

BACKGROUND: Intranasal midazolam and ketamine have been widely used as sedative premedication in children. It is difficult to determine which one yields better sedative effects for clinical practice. We conducted the present meta-analysis by summarizing the evidences to evaluate the efficacy and safety of intranasal midazolam versus intranasal ketamine as sedative premedication in pediatric patients. METHODS: We searched PubMed, Embase, and Cochrane Library from inception to April 2022. All randomized controlled trials (RCTs) used intranasal midazolam and ketamine as sedatives in children were enrolled. The risk of bias in RCTs was assessed by Cochrane risk of bias tool. Condition of parental separation, anesthesia induction or facemask acceptance, sedation level, different hemodynamic parameters and adverse events were considered as the outcomes in our study. RESULTS: A total of 16 studies with 1066 patients were enrolled. Compared with midazolam, administration of intranasal ketamine might be associated with severer changes in hemodynamics parameters including mean blood pressure (SMD = -0.53, with 95% CI [-0.93, -0.13]) and heart rate (HR) (SMD = -1.39, with 95% CI [-2.84, 0.06]). Meanwhile, administration of intranasal midazolam was associated with more satisfactory sedation level (61.76% vs 40.74%, RR = 1.53, with 95%CI [1.28, 1.83]), more rapid onset of sedation (SMD = -0.59, with 95%CI [-0.90, -0.28]) and more rapid recovery (SMD = -1.06, with 95%CI [-1.83, -0.28]). Current evidences also indicated that the differences of various adverse effects between two groups were not significant. CONCLUSIONS: Given that administration of midazolam via intranasal route provides more satisfactory sedative level with less fluctuation of hemodynamics parameters and more rapid onset and recovery, it might be considered as the preferred sedative premedication for pediatric patients compared to ketamine. However, the widespread evidences with low or moderate quality indicated that superiority of intranasal midazolam in pediatric sedation needs to be confirmed by more studies with high quality and large sample size in future. TRIAL REGISTRATION: The protocol of present study was registered with PROSPERO (CRD42022321348).

Enzymatic Primary Amination of Benzylic and Allylic C(sp3)-H Bonds.

Aliphatic primary amines are prevalent in natural products, pharmaceuticals, and functional materials. While a plethora of processes are reported for their synthesis, methods that directly install a free amine group into C(sp3)-H bonds remain unprecedented. Here, we report a set of new-to-nature enzymes that catalyze the direct primary amination of C(sp3)-H bonds with excellent chemo-, regio-, and enantioselectivity, using a readily available hydroxylamine derivative as the nitrogen source. Directed evolution of genetically encoded cytochrome P411 enzymes (P450s whose Cys axial ligand to the heme iron has been replaced with Ser) generated variants that selectively functionalize benzylic and allylic C-H bonds, affording a broad scope of enantioenriched primary amines. This biocatalytic process is efficient and selective (up to 3930 TTN and 96% ee), and can be performed on preparative scale.

Enantioselective Aminohydroxylation of Styrenyl Olefins Catalyzed by an Engineered Hemoprotein.

Chiral 1,2-amino alcohols are widely represented in biologically active compounds from neurotransmitters to antivirals. While many synthetic methods have been developed for accessing amino alcohols, the direct aminohydroxylation of alkenes to unprotected, enantioenriched amino alcohols remains a challenge. Using directed evolution, we have engineered a hemoprotein biocatalyst based on a thermostable cytochrome c that directly transforms alkenes to amino alcohols with high enantioselectivity (up to 2500 TTN and 90 % ee) under anaerobic conditions with O-pivaloylhydroxylamine as an aminating reagent. The reaction is proposed to proceed via a reactive iron-nitrogen species generated in the enzyme active site, enabling tuning of the catalyst's activity and selectivity by protein engineering.

Catalytic Enantioselective Synthesis of a Pyrrolizidine-Alkaloid-Inspired Compound Collection with Antiplasmodial Activity.

A novel enantioselective approach to the synthesis of a compound collection inspired by natural pyrrolizidine alkaloids was developed, employing an enantioselectively catalyzed 1,3-dipolar cycloaddition as the key step. The cycloadducts were obtained with excellent enantio- and diastereoselectivity. Biological evaluation of the resulting compound collection revealed that the compound class has multiple bioactivities, including activity against Plasmodium falciparum 3D7 and inhibition of Hedgehog signaling.

Enantioselective Synthesis of the Spirotropanyl Oxindole Scaffold through Bimetallic Relay Catalysis.

Spirotropanyl oxindole alkaloids like alstonisine and chitosenine show a wide range of bioactivites. We report the first enantioselective synthesis of the spirotropanyl oxindole scaffold by means of a bimetallic relay catalysis strategy. A new class of E-oximino α-diazo ketones was developed for the intramolecular generation of transient azomethine ylides catalyzed by an achiral RhII complex and a subsequent intermolecular 1,3-dipolar cycloaddition catalyzed by a chiral N,N'-dioxide NdIII Lewis acid complex. The enantioselectively catalyzed transformation has broad scope and yields the desired spirotropanyl oxindole cycloadducts in high yields and with very high enantio- and diastereoselectivity.

General Enantioselective C-H Activation with Efficiently Tunable Cyclopentadienyl Ligands.

Cyclopentadienyl (Cp) ligands enable efficient steering of various transition-metal-catalyzed transformations, in particular enantioselective C-H activation. Currently only few chiral Cp ligands are available. Therefore, a conceptually general approach to chiral Cp ligand discovery would be invaluable as it would enable the discovery of applicable Cp ligands and to efficiently and rapidly vary and tune their structures. Herein, we describe the three-step gram-scale synthesis of a structurally diverse and widely applicable chiral Cp ligand collection (JasCp ligands) with highly variable and adjustable structures. Their modular nature and their amenability to rapid structure variation enabled the efficient discovery of ligands for three enantioselective RhIII -catalyzed C-H activation reactions, including one unprecedented transformation. This novel approach should enable the discovery of efficient chiral Cp ligands for various further enantioselective transformations.

Catalytic enantioselective 1,3-dipolar cycloadditions of azomethine ylides for biology-oriented synthesis.

Cycloaddition reactions are among the most powerful methods for the synthesis of complex compounds. In particular, the development and application of the 1,3-dipolar cycloaddition, an important member of this reaction class, has grown immensely due to its powerful ability to efficiently build various five-membered heterocycles. Azomethine ylides are commonly used as dipoles for the synthesis of the pyrrolidine scaffold, which is an important motif in natural products, pharmaceuticals, and biological probes. The reaction between azomethine ylides and cyclic dipolarophiles allows access to polycyclic products with considerable complexity. The extensive application of the 1,3-dipolar cycloaddition is based on the fact that the desired products can be obtained with high yield in a regio- and stereocontrolled manner. The most attractive feature of the 1,3-dipolar cycloaddition of azomethine ylides is the possibility to generate pyrrolidines with multiple stereocenters in a single step. The development of enantioselective cycloadditions became a subject of intensive and impressive studies in recent years. Among many modes of stereoinduction, the application of chiral metal-ligand complexes has emerged as the most viable option for control of enantioselectivity. In chemical biology research based on the principle of biology-oriented synthesis (BIOS), compound collections are prepared inspired by natural product scaffolds. In BIOS, biological relevance is employed as the key criterion to generate hypotheses for the design and synthesis of focused compound libraries. In particular, the underlying scaffolds of natural product classes provide inspiration for BIOS because they define the areas of chemical space explored by nature, and therefore, they can be regarded as "privileged". The scaffolds of natural products are frequently complex and rich in stereocenters, which necessitates the development of efficient enantioselective methodologies. This Account highlights examples, mostly from our work, of the application of 1,3-dipolar cycloaddition reactions of azomethine ylides for the catalytic enantioselective synthesis of complex products. We successfully applied the 1,3-dipolar cycloaddition in the synthesis of spiro-compounds such as spirooxindoles, for kinetic resolution of racemic compounds in the synthesis of an iridoid inspired compound collection and in the synthesis of a nitrogen-bridged bicyclic tropane scaffold by application of 1,3-fused azomethine ylides. Furthermore, we performed the synthesis of complex molecules with eight stereocenters using tandem cycloadditions. In a programmable sequential double cycloaddition, we demonstrated the synthesis of both enantiomers of complex products by simple changes in the order of addition of chemicals. Complex products were obtained using enantioselective higher order [6 + 3] cycloaddition of azomethine ylides with fulvenes followed by Diels-Alder reaction. The bioactivity of these compound collections is also discussed.

Rhodium(II)-catalyzed enantioselective synthesis of troponoids.

We report a rhodium(II)-catalyzed highly enantioselective 1,3-dipolar cycloaddition reaction between the carbonyl moiety of tropone and carbonyl ylides to afford troponoids in good to high yields with excellent enantioselectivity. We demonstrate that α-diazoketone-derived carbonyl ylides, in contrast to carbonyl ylides derived from diazodiketoesters, undergo [6+3] cycloaddition reactions with tropone to yield the corresponding bridged heterocycles with excellent stereoselectivity.

[Influence of silver/silicon dioxide on infrared absorption spectroscopy of sodium nitrate].

Quickly detecting of ocean nutrient was one important task in marine pollution monitoring. We discovered the application of surface-enhanced infrared absorption spectroscopy in the detection of ocean nutrient through researching the evaporation of sodium nitrate solution. The silicon dioxide (SiO2) with highly dispersion was prepared by Stober method, The silver/silica (Ag/SiO2) composite materials were prepared by mixing ammonia solution and silicon dioxide aqueous solution. Three kinds of composite materials with different surface morphology were fabricated through optimizing the experimental parameter and changing the experimental process. The surface morphology, crystal orientation and surface plasmon resonance were investigated by means of the scanning electronic microscope (SEM), X-ray diffraction (XRD), UV-Visible absorption spectrum and infrared ab- sorption spectroscopy. The SEM images showed that the sample A was purified SiO2, sample B and sample C were mixture of silver nanoparticle and silicon dioxide, while sample D was completed nanoshell structure. The absorption spectroscopy showed that there was surface plasmon resonance in the UV-visible region, while there was possibility of surface plasmon resonance in the Infrared absorption region. The effect of Ag/SiO2 composite material on the infrared absorption spectra of sodium nitrite solution was investigated through systematically analyzing the infrared absorption spectroscopy of sodium nitrate solution during its evaporation, i. e. the peak integration area of nitrate and the peak integration area of water molecule. The experimental results show that the integration area of nitrate was enhanced greatly during the evaporation process while the integration area of water molecule decreased continuously. The integration area of nitrate comes from the anti-symmetric stretch vibration and the enhancement of the vibration is attributed to the interface effect of Ag/SiO2 which is consistent with Jensen T.R's result.

Engineering the next-generation synthetic cell factory driven by protein engineering.

Synthetic cell factory offers substantial advantages in economically efficient production of biofuels, chemicals, and pharmaceutical compounds. However, to create a high-performance synthetic cell factory, precise regulation of cellular material and energy flux is essential. In this context, protein components including enzymes, transcription factor-based biosensors and transporters play pivotal roles. Protein engineering aims to create novel protein variants with desired properties by modifying or designing protein sequences. This review focuses on summarizing the latest advancements of protein engineering in optimizing various aspects of synthetic cell factory, including: enhancing enzyme activity to eliminate production bottlenecks, altering enzyme selectivity to steer metabolic pathways towards desired products, modifying enzyme promiscuity to explore innovative routes, and improving the efficiency of transporters. Furthermore, the utilization of protein engineering to modify protein-based biosensors accelerates evolutionary process and optimizes the regulation of metabolic pathways. The remaining challenges and future opportunities in this field are also discussed.

Disease burden and risk factors of children aged 0-14 years in China: a retrospective study on data from the Global Burden of Disease Study 2019.

OBJECTIVES: This study aimed to analyse the current status, trends and risk factors of disease burden from 1990 to 2019 among Chinese children. DESIGN AND PARTICIPANTS: It was a retrospective study on data from the Global Burden of Disease Study 2019 (GBD 2019). Data of disease burden and risk factors were extracted from the GBD 2019. Children were divided into two groups of <5 and 5-14 years. Data were analysed using GBD results query tool, Excel and Pareto analysis. PRIMARY OUTCOME MEASURES: Disability-Adjusted Life Years (DALYs) and deaths. RESULTS: The overall disease burden for both children <5 years and those aged 5-14 years significantly decreased from 1990 to 2019. For children aged <5 years, in 2019, the leading cause of deaths and DALYs were 'neonatal disorders', and the top risk factor was 'low birth weight'. Compared with data of 1990, the ranking of causes of deaths and DALYs in 2019 saw the most significant increase for 'HIV/AIDS and sexually transmitted infections' and 'skin and subcutaneous diseases' respectively. Conversely, the ranking of deaths/DALYs causes that dropped most significantly was 'nutritional deficiencies'. For children aged 5-14, in 2019, the leading deaths and DALYs causes were 'unintentional injuries' and 'mental disorders' respectively. The top risk factors were 'alcohol use' and 'short gestation', respectively. The ranking of deaths and DALYs causes rose most significantly were 'HIV/AIDS and sexually transmitted infections' and 'neonatal disorders', respectively. Conversely, the ranking of deaths causes that dropped most significantly were 'other infectious diseases', 'enteric infections' and 'nutritional deficiencies'. For DALYs, the causes that dropped most significantly in ranking were 'other infectious diseases'. CONCLUSIONS: The disease burden of children has significantly changed from 1990 to 2019, with notable differences between children aged <5 and 5-14 years. To optimise the allocation of health resources, it is necessary to adjust management strategies based on the latest disease burden.