Objective To investigate the effects of periodontitis induced by Prevotella nigrescens(Pn)combined with ligation on cognitive functions in mice.Methods Twenty-four C57BL/6J mice were randomly divided into control group,ligation group,and ligation+Pn treatment(P+Pn)group.Experimental periodontitis was induced by silk ligation of the first molars followed by topical application of Pn for 6 weeks.After modeling,alveolar bone resorption was assessed using micro-CT and histological analysis.Learning and memory abilities of the mice were evaluated using open field test(OFT),novel object recognition test(NORT),and Morris water maze test(MWM).Seven weeks after the start of modeling,the mice were sacrificed for examining histopathological changes in the hippocampus using HE and Nissl staining.Results After 6 weeks of molar ligation,micro-CT revealed horizontal alveolar bone resorption and furcation exposure in the mice,and histological analysis showed apical migration of the junctional epithelium,epithelial ridge hyperplasia,and lymphocyte infiltration,and these changes were obviously worsened in P+Pn group.Alveolar bone height decreased significantly in both ligation groups compared to the control group.Cognitive tests showed that the mice in both of the ligation groups traveled shorter distances in OFT,showed reduced novel object preference in NORT,and exhibited longer escape latencies in MWM,and the mice in P+Pn group had significantly poorer performances in the tests.Histologically,obvious neuronal cytoplasmic degeneration,necrosis,nuclear pyknosis,vacuolation,and reduced Nissl bodies and viable neurons were observed in the hippocampal regions of the mice in the two ligation groups.Conclusion Pn infection aggravates alveolar bone destruction,accelerates necrosis and causes morphological abnormalities of neuronal cells in the hippocampus to reduce cognitive functions of mice with periodontitis.

OBJECTIVES: To investigate the effects of periodontitis induced by Prevotella nigrescens (Pn) combined with ligation on cognitive functions in mice. METHODS: Twenty-four C57BL/6J mice were randomly divided into control group, ligation group, and ligation + Pn treatment (P+Pn) group. Experimental periodontitis was induced by silk ligation of the first molars followed by topical application of Pn for 6 weeks. After modeling, alveolar bone resorption was assessed using micro-CT and histological analysis. Learning and memory abilities of the mice were evaluated using open field test (OFT), novel object recognition test (NORT), and Morris water maze test (MWM). Seven weeks after the start of modeling, the mice were sacrificed for examining histopathological changes in the hippocampus using HE and Nissl staining. RESULTS: After 6 weeks of molar ligation, micro-CT revealed horizontal alveolar bone resorption and furcation exposure in the mice, and histological analysis showed apical migration of the junctional epithelium, epithelial ridge hyperplasia, and lymphocyte infiltration, and these changes were obviously worsened in P+Pn group. Alveolar bone height decreased significantly in both ligation groups compared to the control group. Cognitive tests showed that the mice in both of the ligation groups traveled shorter distances in OFT, showed reduced novel object preference in NORT, and exhibited longer escape latencies in MWM, and the mice in P+Pn group had significantly poorer performances in the tests. Histologically, obvious neuronal cytoplasmic degeneration, necrosis, nuclear pyknosis, vacuolation, and reduced Nissl bodies and viable neurons were observed in the hippocampal regions of the mice in the two ligation groups. CONCLUSIONS Pn infection aggravates alveolar bone destruction, accelerates necrosis and causes morphological abnormalities of neuronal cells in the hippocampus to reduce cognitive functions of mice with periodontitis.
Animals ; Periodontitis/microbiology* ; Mice ; Mice, Inbred C57BL ; Cognition ; Alveolar Bone Loss ; Hippocampus/pathology* ; Male ; Inflammation ; Maze Learning

Isoflavones which mainly distributed in leguminous plants have plenty of health benefits.Isoflavone synthase(IFS)is a membrane-associated cytochrome P450 enzyme(CYP450)which carries out the unique aryl-ring migration and hydroxylation.So far,few crystal structures of plant P450s have been obtained.We determined the crystal structure of IFS from Medicago truncatula at 1.9 ? by MAD method using a selenomethionine substituted crystal and conducted molecular docking and mutagenesis study.The structure of IFS complexed with imidazole exhibits the helix Ⅰa-loop-helix Ⅰβ motif which cor-responds to helix Ⅰ of other P450s.Compared with structures of common P450s,IFS/imidazole structure contains an extra domain,i.e.,the γ-domain.The structure reveals a homodimer in which the γ-domain of one molecule interacts with the β-domain of another.The plane of heme group makes an angle of ap-proximately 40° with the helix Ⅰa-loop-helix Ⅰβ motif.Molecular docking combined with mutagenesis study suggested that Trp-128 and Asp-300 might play important roles in substrate binding and recogni-tion.Phe-301,Ser-303 and Gly-305 from the helix Ⅰa-loop-helix Ⅰβ motif may play important roles in the aryl-ring migration.These novel structural features reveal insights into the unique reaction mechanism of IFS and provide a basis for engineering IFS in leguminous crops for health purpose.

Isoflavones which mainly distributed in leguminous plants have plenty of health benefits.Isoflavone synthase(IFS)is a membrane-associated cytochrome P450 enzyme(CYP450)which carries out the unique aryl-ring migration and hydroxylation.So far,few crystal structures of plant P450s have been obtained.We determined the crystal structure of IFS from Medicago truncatula at 1.9 ? by MAD method using a selenomethionine substituted crystal and conducted molecular docking and mutagenesis study.The structure of IFS complexed with imidazole exhibits the helix Ⅰa-loop-helix Ⅰβ motif which cor-responds to helix Ⅰ of other P450s.Compared with structures of common P450s,IFS/imidazole structure contains an extra domain,i.e.,the γ-domain.The structure reveals a homodimer in which the γ-domain of one molecule interacts with the β-domain of another.The plane of heme group makes an angle of ap-proximately 40° with the helix Ⅰa-loop-helix Ⅰβ motif.Molecular docking combined with mutagenesis study suggested that Trp-128 and Asp-300 might play important roles in substrate binding and recogni-tion.Phe-301,Ser-303 and Gly-305 from the helix Ⅰa-loop-helix Ⅰβ motif may play important roles in the aryl-ring migration.These novel structural features reveal insights into the unique reaction mechanism of IFS and provide a basis for engineering IFS in leguminous crops for health purpose.

Soy is a vital source of plant carbohydrates.However,it poses significant allergenic risks,particularly to young children and animals.Among the various proteins in soy,β-conglycinin,which con-stitutes approximately 30％of total soy carbohydrates,is a primary allergen.Undigested β-conglycinin can lead to intestinal damage by inhibiting cell growth,disrupting the cytoskeleton,and inducing apopto-sis.It can also enter the lymphatic and circulatory systems,triggering allergic reactions.Conventional ELISA methods for detecting β-conglycinin rely on polyclonal or monoclonal antibodies,which are limited by their large molecular weight,difficulty in accessing the protein core,and sensitivity to acidic and bas-ic conditions.To address these limitations,this study aimed to develop nanobodies(Nbs)against β-con-glycinin.Nbs,derived from the variable regions of heavy-chain antibodies found in camelids,have a mo-lecular weight approximately one-tenth that of conventional antibodies.They offer advantages such as small size,stable structure,high specificity,and strong affinity.A female alpacas was immunized five times using β-conglycinin,which showed a heavy chain antibody potency of 1∶16 000 by ELISA.Pe-ripheral blood lymphocytes were subsequently isolated and total RNA was extracted.The variable region of the heavy-chain antibody was amplified via PCR,and recombinant plasmids were constructed and transformed into the E.coli competency strain ER2738.The resulting library contained about 3.5×108 CFU/mL,which increased to 1.15×1012 PFU/mL after phage rescue,with a 100％Nbs gene insertion rate,indicating high diversity.Its Nbs phage output was significantly enriched by four rounds of solid-phase elution with an enrichment rate of 155.9.Four rounds of solid-phase panning yielded 35 positive clones,all of which shared the same amino acid sequence upon sequencing.The selected Nb was ex-pressed in a prokaryotic system,and its binding ability to β-conglycinin was confirmed using Western blotting and ELISA.The results demonstrated excellent specificity and affinity.This research lays the groundwork for developing a rapid and efficient detection method for β-conglycinin using Nbs,potentially enhancing food safety and allergen management.

Soy is a vital source of plant carbohydrates.However,it poses significant allergenic risks,particularly to young children and animals.Among the various proteins in soy,β-conglycinin,which con-stitutes approximately 30％of total soy carbohydrates,is a primary allergen.Undigested β-conglycinin can lead to intestinal damage by inhibiting cell growth,disrupting the cytoskeleton,and inducing apopto-sis.It can also enter the lymphatic and circulatory systems,triggering allergic reactions.Conventional ELISA methods for detecting β-conglycinin rely on polyclonal or monoclonal antibodies,which are limited by their large molecular weight,difficulty in accessing the protein core,and sensitivity to acidic and bas-ic conditions.To address these limitations,this study aimed to develop nanobodies(Nbs)against β-con-glycinin.Nbs,derived from the variable regions of heavy-chain antibodies found in camelids,have a mo-lecular weight approximately one-tenth that of conventional antibodies.They offer advantages such as small size,stable structure,high specificity,and strong affinity.A female alpacas was immunized five times using β-conglycinin,which showed a heavy chain antibody potency of 1∶16 000 by ELISA.Pe-ripheral blood lymphocytes were subsequently isolated and total RNA was extracted.The variable region of the heavy-chain antibody was amplified via PCR,and recombinant plasmids were constructed and transformed into the E.coli competency strain ER2738.The resulting library contained about 3.5×108 CFU/mL,which increased to 1.15×1012 PFU/mL after phage rescue,with a 100％Nbs gene insertion rate,indicating high diversity.Its Nbs phage output was significantly enriched by four rounds of solid-phase elution with an enrichment rate of 155.9.Four rounds of solid-phase panning yielded 35 positive clones,all of which shared the same amino acid sequence upon sequencing.The selected Nb was ex-pressed in a prokaryotic system,and its binding ability to β-conglycinin was confirmed using Western blotting and ELISA.The results demonstrated excellent specificity and affinity.This research lays the groundwork for developing a rapid and efficient detection method for β-conglycinin using Nbs,potentially enhancing food safety and allergen management.

[Objective]To investigate the difference of ultrasound characteristics between pure mucinous carcinoma(PMC)and fibroadenoma(FA)of the breast.[Methods]Ultrasound data of 50 continuous patients with breast PMC from January 2012 to January 2021 and 100 continuous patients with breast FA from June 2018 to January 2019 in Sun Yat-sen Memorial Hospital of Sun Yat-sen University were retrospectively reviewed.The ultrasound characteristics of the two groups were evaluated according to the 2013 BI-RADS Ultrasound Atlas,and the differences in age,maximum diameter and ultrasound characteristics between the two groups were compared.[Results]The median age of PMC patients was 47 years and that of FA patients was 33 years.The age of PMC patients was higher than that of the FA group,and the differ-ence between the two groups of patients was statistically significant(P<0.001).The median maximum diameter of PMC pa-tients was 2.4 cm,which was greater than that of the FA group(1.8 cm),and the difference was statistically significant(P=0.001).Of the PMC,70%(35/50)were irregular,82%(41/50)were parallel to the skin,92%(46/50)had no circum-scribed margin,72%(36/50)were hypoechoic,and 68%(34/50)had enhanced posterior echo.Of the FA,69%(69/100)were oval or round,98%(98/100)were parallel to the skin,54%(54/100)had circumscribed margin,98%(98/100)were hypoechoic,and 75%(75/100)had no posterior features.The differences in the above ultrasound characteris-tics between the PMC and FA groups were statistically significant(P<0.001,P=0.001,P<0.001,P<0.001,P<0.001).There was no significant difference between calcifications and blood flow.[Conclusions]Compared with the FA group,pa-tients with PMC are older and the diameter of the lesions are larger.On ultrasound,the morphology and margin of most breast PMC still show the growth characteristics of invasive cancer.Meanwhile,the posterior echo of PMC is enhanced,which is a unique manifestation.

The detection principle of microfluidic microfluidic technology was introduced.The current research status of microfluidic platform-based SARS-CoV-2 nucleic acid detection technologies were reviewed such as reverse transcription quantitative real-time polymerase chain reaction(RT-qPCR),digital PCR,isothermal amplification and clustered regularly interspaced palindromic repeats/CRISPR-associated protein.The deficiencies of microfluidic platform-based SARS-CoV-2 nucleic acid detection were analyzed.It's pointed out microfluidic platform-based SARS-CoV-2 nucleic acid detection had to be optimized and validated clinically in specialty,sensitivity,detection limit,reproducibility,informatization,quality control and reagent cost.[Chinese Medical Equipment Journal,2024,45(1):101-107]

Objective To investigate the prognosis of patients with hepatitis B virus(HBV)-related intrahepatic cholangiocarcinoma(ICC)whose HBV DNA was negative before surgical.Methods A retrospective analysis was conducted on the clinical data of 97 ICC patients who underwent surgery resection at the Fifth Medical Center of Chinese PLA General Hospital between October 2010 and January 2017.All patients were divided into HBV-related ICC(HBV-ICC)group(n=62)and non-HBV-related ICC(Con-ICC)group(n=35).HBV-ICC group included 34 patients with HBV core antigen positive(HBcAb+)and HBV surface antigen positive(HBsAg+),and 28 patients with HBcAb positive and HBsAg negative.Kaplan-Meier analysis was used to plot survival curves and compare the overall survival(OS)and postoperative recurrence-free survival(RFS)among patients in Con-ICC,ICC patients with HBsAg+/HBcAb+,and ICC patients with HBsAg-/HBcAb+.Univariate and multivariate Cox proportional hazard models were used to analyze independent influencing factor for OS,RFS and early postoperative recurrence among gender,age,pathogenic factor,liver cirrhosis,Child-Pugh grade,carbohydrate antigen 19-9(CA199),alpha-fetoprotein(AFP),glutamine transferase(GGT),alkaline phosphatase(ALP),total bilirubin(TBil),direct bilirubin(DBil),American Joint Committee on Cancer(AJCC)stage,tumor size,tumor number,tumor differentiation,microvascular invasion,lymph node metastasis,hepatectomy procedure,cholecystectomy,and follow-up treatment.Results Of the 97 patients,the median age was 56 years,and 79(81.4%)of them were male.The median follow-up time was 92.2 months.Eighty-eight(90.7%)patients presented with tumor recurrence and 73(75.3%)died.In multivariate analyses,HBV-ICC and CA199>37 kU/L were independent predictors of OS(HR=0.45,95%CI 0.26-0.77,P=0.003;HR=2.10,95%CI 1.24-3.57,P=0.006),RFS(HR=0.43,95%CI 0.27-0.68,P<0.001;HR=1.78,95%CI 1.12-2.81,P=0.014),and postoperative early recurrence(HR=0.42,95%CI 0.26-0.70,P=0.001;HR=2.02,95%CI 1.20-3.39,P=0.008).AJCC stage Ⅲ was an independent risk factor for postoperative RFS(HR=1.81,95%CI 1.04-3.14,P=0.037).Multiple tumor lesions was an independent risk factor for postoperative RFS and early recurrence(HR=1.73,95%CI 1.07-2.77,P=0.024;HR=1.90,95%CI 1.12-3.24,P=0.017).There was no statistically significant difference in OS,RFS,and early recurrence between HBV-ICC patients with HBsAg-/HBcAb+and Con-ICC patients(P<0.05),whereas HBsAg+/HBcAb+was a significant factor affecting postoperative OS(HR=0.32,95%CI 0.16-0.62,P=0.001),RFS(HR=0.32,95%CI 0.18-0.55,P<0.001),and early recurrence(HR=0.29,95%CI 0.15-0.54,P<0.001)in ICC patients.Conclusions The prognosis of HBV-ICC patients with preoperative HBV-DNA-is better than that of Con-ICC patients.The prognosis of HBV-ICC patients with HBcAb+/HBsAg-is worse than that of HBV-ICC patients with HBcAb+/HBsAg+,but similar to Con-ICC patients.Therefore,the postoperative stratified management of HBV-ICC patients should be emphasized.

By using thioflavin T(ThT)as displacement-based fluorescent probes,three kinds of aptasensors were constructed for rapid detection of three kinds of small molecules such as ochratoxin A(OTA),aflatoxin B1(AFB1)and adenosine.In the absence of target molecule,ThT bound with the aptamer to form an aptamer-ThT complex and exhibited a significant fluorescence response.Upon the addition of target molecule,because of the higher affinity between target and aptamer than that between ThT and the aptamer,ThT was displaced by the target molecule from the aptamer-ThT complex,resulting in weakened fluorescence signal.Based on this principle,the target molecule could be detected quantitatively.Further study through circular dichroism spectra showed that there was no significant change in the conformation of the aptamer after addition of ThT or target molecules.The stoichiometric ratios of ThT to OTAapt,AFB1apt and Adeapt measured through the method of equimolar continuous variation was 1∶1,1∶1 and 2∶1,respectively,and their dissociation constants were all larger than those between the target molecule and its aptamer.Therefore,the principle of this detection method was the displacement of fluorescent probe(ThT)in aptamer-ThT complex by target molecule,resulting in decrease of fluorescence intensity.Under optimal experimental conditions,the limits of detection(LODs)were 0.8 nmol/L for OTA,1.3 nmol/L for AFB1,and 0.10 μmol/L for adenosine,respectively.This method was label-free,simple to operate,with low cost,good selectivity and high sensitivity.The developed assay kit based on this method could be used for actual sample detection.