Platycodonis Radix is the dry root of Platycodon grandiflorum of Campanulaceae, which has a variety of pharmacological effects and is a commonly used bulk Chinese medicine. In this study, the chloroplast genome sequences of six P. grandiflorum from different producing areas has been sequenced with Illumina HiSeq X Ten platform. The specific DNA barcodes were screened, and the germplasm resources and genetic diversity were analyzed according to the specific barcodes. The total length of the chloroplast genome of 6 P. grandiflorum samples was 172 260-172 275 bp, and all chloroplast genomes showed a typical circular tetrad structure and encoded 141 genes. The comparative genomics analysis and results of amplification efficiency demonstrated that trnG-UCC and ndhG_ndhF were the potential specific DNA barcodes for identification the germplasm resources of P. grandiflorum. A total of 305 P. grandiflorum samples were collected from 15 production areas in 9 provinces, for which the fragments of trnG-UCC and ndhG_ndhF were amplificated and the sequences were analyzed. The results showed that trnG-UCC and ndhG_ndhF have 5 and 11 mutation sites, respectively, and 5 and 7 haplotypes were identified, respectively. The combined analysis of the two sequences formed 13 haplotypes (named Hap1-Hap13), and Hap4 is the main genotype, followed by Hap1. The unique haplotypes possessed by the three producing areas can be used as DNA molecular tags in this area to distinguish from the germplasm resources of P. grandiflorum from other areas. The haplotype diversity, nucleotide diversity and genetic distance were 0.94, 4.79×10^-3 and 0.000 0-0.020 3, respectively, suggesting that the genetic diversity was abundant and intraspecific kinship was relatively close. This study laid a foundation for the identification of P. grandiflorum, the protection and utilization of germplasm resources, and molecular breeding.

Objective To explore the correlation between speech fluency and diadochokinetic rate in children aged 7～11 years with cochlear implant.Methods Speech samples were collected from 62 children aged 7～11 years with cochlear implant using language retelling task and diadochokinetic rate test task.Their speech rate,articulation rate,syllable duration and pause duration were analyzed.The data were input into ICF converter to obtain the im-pairment limit of each parameter and analyze the speech fluency and diadochokinetic rate characteristics.Partial cor-relation analysis was performed for speech rate,articulation rate,syllable duration and pause duration by two tasks.Results ① For children with cochlear implant,the mean ICF impairment limit of diadochokinetic rate was 1.3± 0.1,the mean ICF impairment limit of fluency in retelling was 1.0±0.3,with various degree of impairment in both tasks.② There was a moderate or low correlation between speech rate,articulation rate,syllable duration in retell-ing task and those in diadochokinetic rate task(0.3＜|r |≤0.8).There was a low correlation between pause dura-tion in retelling task and speech rate and pause duration in diadochokinetic rate task(0.3＜|r |≤0.5).Conclusion The speech fluency and diadochokinetic rate of children aged 7～11 years with cochlear implant is underdeveloped,and the poor articulation movement ability limits their development of speech fluency.

AIM: To observe the changes of corneal densitometry(CD)in patients with keratoconus after corneal cross-linking(CXL).METHODS: Retrospective study. A total of 32 patients(43 eyes)with keratoconus in Ningxia Eye Hospital from April 2020 to April 2022 were selected. Pentacam analysis system divided the cornea into three layers: anterior 120 μm, middle layer and posterior 60 μm, and divides it into five regions with diameters of 0-2, 2-6, 6-10, 10-12 mm and full diameter according to the diameter, and measures the CD in different ranges. The changes of CD were compared before operation and at 1, 3 and 6 mo after operation.RESULTS: There were differences in uncorrected visual acuity, best corrected visual acuity and intraocular pressure before and 6 mo after operation(all P<0.05), and there was no difference in corneal endothelial cells(P=0.477). CD reached its peak at 1 mo after operation, and decreased at 3 mo and 6 mo after operation, but it was still higher than that before operation. There is a significant positive correlation between CD and Kmax in the anterior layer and the whole layer(r=0.164, P=0.016; r=0.152, P=0.023).CONCLUSION: The values of CD peaked at 1 mo after CXL, then it gradually decreased, tending to become stable at 6 mo postoperatively.

italic>Acanthopanax senticosus is one of the genuine regional herb in Northeast China. In this study, we identified the germplasm resources of commercial A. senticosus samples based on atpI and atpB_rbcL according to the previous chloroplast genome sequencing results, and determinated the content of syringin by HPLC to evaluated the quality of commercial samples. A total of 80 A. senticosus samples were collected from 47 cities in 24 provinces. DNA was extracted to amplify the products of atpI and atpB_rbcL by PCR. The results showed that 7 haplotypes (H2, H5, H8, H10, H12, H14, H23) were formed by the combined analysis of the two gene fragments. H2 from Yichun in Heilongjiang, Shangzhi in Harbin, Suihua in Heilongjiang, Fushun in Liaoning, Benxi in Liaoning, Changbai in Jilin and Jingyu in Jilin were the dominant genotype, representing 58.75% of the total samples. H14 and H23 were the unique haplotypes of the producing area. It is speculated that the commercial A. senticosus samples with haplotypes of H14 and H23 are from Raohe, Shuangyashan, Heilongjiang and Mingshui, Suihua, Heilongjiang, respectively. HPLC analysis indicated that the content of syringin in 73.96% of the samples met the Pharmacopoeia standards. There was a significant difference in the content of syringin among the samples, ranging from 0.003 7% to 0.524 5%, with a difference of 0.520 8%, indicating that the quality of the samples in the market of A. senticosus was uneven. However, there were no significant differences in the contents of syringin in the commercial A. senticosus among different haplotypes. The content of syringin in the haplotype H23 in the market sample is relatively high, so it may be a germplasm with better quality. This study researched the germplasm resources and medicinal materials quality of commercial A. senticosus samples and will help guide the commercial circulation, reasonable medication of A. senticosus, and the screening of excellent germplasm.

Bacterial biofilms gave rise to persistent infections and multi-organ failure, thereby posing a serious threat to human health. Biofilms were formed by cross-linking of hydrophobic extracellular polymeric substances (EPS), such as proteins, polysaccharides, and eDNA, which were synthesized by bacteria themselves after adhesion and colonization on biological surfaces. They had the characteristics of dense structure, high adhesiveness and low drug permeability, and had been found in many human organs or tissues, such as the brain, heart, liver, spleen, lungs, kidneys, gastrointestinal tract, and skeleton. By releasing pro-inflammatory bacterial metabolites including endotoxins, exotoxins and interleukin, biofilms stimulated the body’s immune system to secrete inflammatory factors. These factors triggered local inflammation and chronic infections. Those were the key reason for the failure of traditional clinical drug therapy for infectious diseases.In order to cope with the increasingly severe drug-resistant infections, it was urgent to develop new therapeutic strategies for bacterial-biofilm eradication and anti-bacterial infections. Based on the nanoscale structure and biocompatible activity, nanobiomaterials had the advantages of specific targeting, intelligent delivery, high drug loading and low toxicity, which could realize efficient intervention and precise treatment of drug-resistant bacterial biofilms. This paper highlighted multiple strategies of biofilms eradication based on nanobiomaterials. For example, nanobiomaterials combined with EPS degrading enzymes could be used for targeted hydrolysis of bacterial biofilms, and effectively increased the drug enrichment within biofilms. By loading quorum sensing inhibitors, nanotechnology was also an effective strategy for eradicating bacterial biofilms and recovering the infectious symptoms. Nanobiomaterials could intervene the bacterial metabolism and break the bacterial survival homeostasis by blocking the uptake of nutrients. Moreover, energy-driven micro-nano robotics had shown excellent performance in active delivery and biofilm eradication. Micro-nano robots could penetrate physiological barriers by exogenous or endogenous driving modes such as by biological or chemical methods, ultrasound, and magnetic field, and deliver drugs to the infection sites accurately. Achieving this using conventional drugs was difficult. Overall, the paper described the biological properties and drug-resistant molecular mechanisms of bacterial biofilms, and highlighted therapeutic strategies from different perspectives by nanobiomaterials, such as dispersing bacterial mature biofilms, blocking quorum sensing, inhibiting bacterial metabolism, and energy driving penetration. In addition, we presented the key challenges still faced by nanobiomaterials in combating bacterial biofilm infections. Firstly, the dense structure of EPS caused biofilms spatial heterogeneity and metabolic heterogeneity, which created exacting requirements for the design, construction and preparation process of nanobiomaterials. Secondly, biofilm disruption carried the risk of spread and infection the pathogenic bacteria, which might lead to other infections. Finally, we emphasized the role of nanobiomaterials in the development trends and translational prospects in biofilm treatment.

Aim To investigate the effect of quercetin on the aging model of bone marrow mesenchymal stem cells established under microgravity. Methods Using 3D gyroscope, a aging model of bone marrow mesenchymal stem cells was constructed, and after receiving quercetin and microgravity treatment, the anti-aging effect of the quercetin was evaluated by detecting related proteins and oxidation indexes. Results Compared to the control group, the expressions of age-related proteins p21, pi6, p53 and RB in the microgravity group significantly increased, while the expressions of cyclin D1 and lamin B1 significantly decreased, with statistical significance (P<0.05). In the microgravity group, mitochondrial membrane potential significantly decreased (P<0.05), ROS accumulation significantly increased (P <0.05), SOD content significantly decreased and MDA content significantly increased (P<0.05). Compared to the microgravity group, the expressions of age-related proteins p21, pi6, p53 and RB in the quercetin group significantly decreased, while the expressions of cyclin D1 and lamin B1 significantly increased, with statistical significance (P<0.05). In the quercetin group, mitochondrial membrane potential significantly increased (P<0.05), ROS accumulation significantly decreased (P<0.05), SOD content significantly increased and MDA content significantly decreased (P<0.05). Conclusions Quercetin can resist oxidation, protect mitochondrial function and normal cell cycle, thus delaying the aging of bone marrow mesenchymal stem cells induced by microgravity.

Additive manufacturing(3D printing)technology aligns with the direction of precision and customization in future medicine,presenting a significant opportunity for innovative development in high-end medical devices.Currently,research and industrialization of 3D printed medical devices mainly focus on nondegradable implants and degradable implants.Primary areas including metallic orthopaedic implants,polyether-ether-ketone(PEEK)bone implants,and biodegradable implants have been developed for clinical and industrial application.Recent research achievements in these areas are reviewed,with a discussion on the additive manufacturing technologies and applications for customized implants.Challenges faced by different types of implants are analyzed from technological,application,and regulatory perspectives.Furthermore,prospects and suggestions for future development are outlined.

Objective To observe the effect of electric stimulation on nuclear factor-κB(NF-κB)/NOD-like receptor protein 3(NLRP3)signaling pathway and microglial cell morphology in mice with lipopolysaccharide(LPS)induced chronic neuroinflammation,and to explore the protective mechanism of electric stimulation on brain of mice.Methods C57BL/6 mice were randomly divided into blank control group(n=8),model group(n=12),sham electroacupuncture group(n=6)and electroacupuncture group(n=6).Except blank control group,mice in other groups were injected intraperitoneally with LPS(0.25 mg/kg)for 7 consecutive days.On the 8th day,mice in the sham electroacupuncture group and electroacupuncture group were treated with acupuncture or Zusanli electroacupuncture for 7 consecutive days.The mice were weighed before the experiment,on the 7th and 14th days.On the 13th day,the elevated cross maze test was performed on the mice.The open field test was performed on the 14th day.After the experiment,immunofluorescence assay was used to determine the expression of microglial ionized calcium binding adaptor molecule-1(Iba-1)in prefrontal cortex region.The mRNA expression of NF-κB,inducible nitric oxide synthase(iNOS),tumor necrosis factor-α(TNF-α),Caspase-1 and interleukin(IL)-18 were detected by Real-time PCR.The protein expression levels of NF-κB,iNOS,NLRP3,apoptosis-associated speck-like protein containing a CARD(ASC),Caspase-1,IL-1βand IL-18 were detected by Western blotting.Results Weight change,On the 7th day,compared with the control group,the body weight of mice in model group,sham electroacupuncture group and electroacupuncture group decreased(P＜0.0001),respectively;On the 14th day,compared with the control group,the weight of mice in the model group decreased(P＜0.0001);Compared with the sham electroacupuncture group,the body weight of mice in the electroacupuncture group increased(P＜0.05).Elevated cross maze experiment,compared with the control group,the total distance and open arm retention time of mice in model group decreased,while the closed arm retention time increased(P＜0.05).The open field experiment showed that compared with the control group,the model group mice showed a decrease in total distance traveled,slower movement speed,and fewer entries into the central area(P＜0.001);Compared with the model group,the electroacupuncture group showed an increase in all three indicators(P＜0.01);Compared with the sham electroacupuncture group,the total distance and motion speed of mice in electroacupuncture group both increased(P＜0.05).Immunofluorescence assay,compared with the control group,the relative fluorescence of Iba-1 in prefrontal cortex area of mice in model group increased(P＜0.05).Compared with the model and sham electroacupuncture group,the relative fluorescence of Iba-1 in prefrontal cortex area of mice in electroacupuncture group decreased(P＜0.05).Real-time PCR showed that compared with the control group,mRNA expressions of NF-κB,iNOS,TNF-α,Caspase-1 and IL-18 in the model group increased(P＜0.05);Compared with the model group,mRNA expressions of NF-κB,iNOS,TNF-α,Caspase-1 and IL-18 in electroacupuncture group decreased(P＜0.05).Western blotting indicated that compared with the control group,the protein expressions of NF-κB,iNOS,Caspase-1,IL-1β and IL-18 in model group increased(P＜0.05);Compared with model group,the protein expressions of NF-κB,iNOS,NLRP3,ASC,Caspase-1,IL-1β and IL-18 in electroacupuncture group decreased(P＜0.05);Compared with the sham electroacupuncture group,IL-18 protein in electroacupuncture group decreased(P＜0.05).Conclusion Electroacupuncture can improve the behavioral performance of mice and inhibit the activation of microglia in the cortical region of mice,which may play an anti-inflammatory and protective role by regulating NF-κB/NLRP3 pathway.

Objective To investigate the infectivity of hepatitis A virus(HAV)cell-adapted strain in a type Ⅰ interferon receptor-deficient mouse model.Methods The biological charateristics of HM175/18f were identified,including the viral protein expression and viral proliferation by indirect immunofluorescence,Western blot and real-time quantitative RT-PCR in vitro.Then,type Ⅰ interferon receptor-deficient A129 mice were infected with HM175/18f via intravenous injection.The viral RNA load in serum,feces and liver tissues of infected mice were detected to determine the replication of HAV in vivo.The level of serum alanine aminotransferase(ALT)and HE staining of liver tissues were used to evaluate liver injury.Additionally,the dynamic changes of HAV-specific IgG antibody was detected to assess the humoral immune response induced by HM175/18f.Results A129 mice infected with HM175/18f did not show obvious clinical symptoms,nor was the ALT level significantly elevated.However,viral RNA persisted in the liver tissue of infected mice until 42 days after infection.There was focal infiltration of lymphocytes and neutrophils in the liver tissue of infected mice,but no focal necrosis was observed.More importantly,HM175/18f infection caused significant viremia and sustained fecal virus shedding.In addition,HM175/18f induced a significant HAV-specific humoral immune response in A129 mice.Conclusion Our study has revealed the infectivity of HAV cell-adapted strain HM175/18f in type Ⅰ interferon receptor-deficient mice,and identified the attenuated characteristics of HM175/18f,which not only contributes to our understanding of the pathogenesis of HAV,but also expand the applications of a type Ⅰ interferon receptor-deficient mouse model in the study of hepatitis A.

Objective To study the in vitro expression of three phenylalanine hydroxylase(PAH)mutants(p.R243Q,p.R241C,and p.Y356X)and determine their pathogenicity.Methods Bioinformatics techniques were used to predict the impact of PAH mutants on the structure and function of PAH protein.Corresponding mutant plasmids of PAH were constructed and expressed in HEK293T cells.Quantitative reverse transcription polymerase chain reaction was used to measure the mRNA expression levels of the three PAH mutants,and their protein levels were assessed using Western blot and enzyme-linked immunosorbent assay.Results Bioinformatics analysis predicted that all three mutants were pathogenic.The mRNA expression levels of the p.R243Q and p.R241C mutants in HEK293T cells were similar to the mRNA expression level of the wild-type control(P>0.05),while the mRNA expression level of the p.Y356X mutant significantly decreased(P<0.05).The PAH protein expression levels of all three mutants were significantly reduced compared to the wild-type control(P<0.05).The extracellular concentration of PAH protein was reduced in the p.R241C and p.Y356X mutants compared to the wild-type control(P<0.05),while there was no significant difference between the p.R243Q mutant and the wild type control(P>0.05).Conclusions p.R243Q,p.R241C and p.Y356X mutants lead to reduced expression levels of PAH protein in eukaryotic cells,with p.R241C and p.Y356X mutants also affecting the function of PAH protein.These three PAH mutants are to be pathogenic.[Chinese Journal of Contemporary Pediatrics,2024,26(2):188-193]