Osteoarthritis (OA) is a chronic degenerative joint disease and the most common type of arthritis. It involves almost any joint and can lead to chronic pain and disability. In the late 19th century, Roentgen discovered X-rays, and then began to use radiotherapy to treat tumors. In the 1980s, Luckey thought that low-level radiation (LDRT) might be beneficial to biology, and it was gradually applied to the treatment of some diseases. This paper introduces the epidemiology, risk factors, clinical manifestations and treatment methods of OA, points out that the cartilage injury and the important effect of synovial inflammation in the pathogenesis of OA, namely when the homeostasis of articular cartilage are destroyed, synthetic metabolism and catabolism imbalances, cartilage cells damaged their breakdown products consumed by synovial cells. Synovial cells and synovial macrophages secrete proinflammatory cytokines, metalloproteinases and proteolytic enzymes, leading to cartilage matrix degradation and chondrocyte damage, which aggravates synovial inflammation and cartilage damage, forming a vicious cycle. The possible mechanism and clinical research progress of LDRT in alleviating OA are discussed. LDRT can regulate inflammatory response, inhibit the production of pro-inflammatory cytokines, and promote the production of anti-inflammatory cytokines, thereby achieving anti-inflammatory effect. Studies have shown that after irradiation, the expression of inducible nitric oxide synthase (iNOS) was decreased, the release of reactive oxygen species (ROS) and the production of superoxide were inhibited, the anti-inflammatory phenotype of macrophages was differentiated from M1 to M2, the inflammatory CD8⁺ T cells were transformed into CD4⁺ T cells, and the number of dendritic cells (DC) was significantly reduced. LDRT inhibit the production of proinflammatory factors in leukocytes, reduce their recruitment and adhesion, and down-regulate the expression levels of cell adhesion molecules such as selectin, intercellular adhesion molecule (ICAM) and vascular endothelial cell adhesion molecule (VCAM). LDRT can regulate endothelial cells, stimulate endothelial cells to produce a large amount of TGF-β1, reduce the adhesion of endothelial cells to peripheral blood mononuclear cells (PBMC), and contribute to the anti-inflammatory effect of LDRT. It also exerted anti-inflammatory effects by regulating mitochondrial growth differentiation factor 15 (GDF15). After low-level radiation, the MMP-13 (matrix metalloproteinases-13) and the ADAMTS5 (recombinant a disintegrin and metalloproteinase with thrombospondin-5) decreased, the Col2a1 (collagen type 2) increased in chondrocytes. In the existing clinical studies, most patients can achieve relief of joint pain and recovery of joint mobility after irradiation, and the patients have good feedback on the efficacy. The adverse reactions (acute reactions and carcinogenic risks) caused by LDRT in the treatment of OA are also discussed. During the treatment of OA, a few patients have symptoms such as redness, dryness or itching at the joint skin, and the symptoms are mild and do not require further treatment. Patients are thus able to tolerate more frequent and longer doses of radiotherapy. In general, LDRT itself has the advantages of non-invasive, less adverse reactions, and shows the effect of pain relief and movement improvement in the treatment of OA. Therefore, LDRT has a broad application prospect in the treatment of OA.

Objective To explore the clinical characteristics and treatment scheme of periprosthetic joint infection(PJI)caused by Cutibacterium avidum(C.avidum).Methods The diagnosis and treatment process of a patient with PJI caused by C.avidum was summarized,and relevant literatures in the database were retrieved for review.Results A 65-year-old female patient with body mass index(BMI)of 31.1 kg/m2 underwent left humeral head prosthesis replacement surgery following a left proximal humerus fracture.Ten months after the surgery,the pa-tient exhibited poor wound healing and oozing,along with limited movement of the left shoulder joint,and was diag-nosed infection following shoulder arthroplasty.Patient underwent debridement of the infected lesion and removal of the prosthesis.The tissue,bone cement and prosthesis were cultured for C.avidum.Four literatures were re-trieved and screened,a total of 30 patients with PJI(28 cases hip joint infection and 2 cases shoulder joint infection)caused by C.avidum were reported through literature retrieval,and 78.6％(n=22)total hip arthroplasty(THA)surgeries were performed using direct anterior approach(DAA).The positive rate of preoperative joint fluid culture was 71.4％,29 cases underwent surgical combined with sensitive antimicrobials treatment.Except for one patient who had repeated infection and underwent three surgeries,other patients had a good prognosis.Conclusion PJI caused by C.avidum is mostly seen in THA patients who are obese and undergo DAA,with a few cases reported after shoulder arthroplasty.The high sensitivity of preoperative joint fluid culture provides an important basis for the development of surgical strategies and anti-infection protocols.

AIM To establish an HPLC method for the simultaneous content determination of gallic acid,protocatechuic acid,morroniside,loganin,sweroside,paeoniflorin,hypericin,astragalin,salvianolic acid B,salvianolic acid A,epimedin C and icariin in Bushen Huoxue Sanjie Capsules.METHODS The analysis was performed on a 30℃thermostatic Agilent 5 TC-C18 column(250 mm×4.6 mm,5 μm),with the mobile phase comprising of acetonitrile-0.1%phosphoric acid flowing at 1.0 mL/min in a gradient elution manner,and the detection wavelength was set at 240 nm.RESULTS Twelve constituents showed good linear relationships within their own ranges(r≥0.999 8),whose average recoveries were 97.11%-101.14%with the RSDs of 0.60%-2.65%.CONCLUSION This simple,accurate and reproducible method can be used for the quality control of Bushen Huoxue Sanjie Capsules.

Objective To investigate the effect of chemokine CXC ligand 9(CXCL9)on cognitive function impairment in patients with breast cancer brain metastases undergoing whole-brain radiotherapy(WBRT)using bioinformatics methods.Methods The mRNA of breast cancer brain metastases datasets GSE43837 and GSE12276 and Alzheimer's disease(AD)dataset GSE161199 were screened and downloaded from GEO database.Limma method and Venn diagrams were used to identify common differentially expressed genes(DEGs),and protein-protein interaction and functional prediction through GeneMANIA website assays were performed.A total of 42 patients with breast cancer brain metastases who first visited the Department of Radiotherapy at the First Affiliated Hospital of Hebei North University from January 2021 to January 2023 were selected.Patients were divided into normal cognitive function group and cognitive function impairment group based on cognitive status.Enzyme-linked immunosorbent assay(ELISA)was employed to detect serum CXCL9 levels one week before and three months after radiotherapy.The mini-mental state examination(MMSE)was used to assess patients'cognitive function.Results The DEGs from datasets GSE43837 and GSE12276 included PKP1,POLDIP2,SPAG5,ALDOC,PTPRZ1,PKIA,TLCD1,CPE,PMP22 and CXCL9.The DEGs from GSE161199 included RPS16,CD79A,LYPD3,RPL28,HBG2,RPL23AP7,TRNR,CXCL9.Venn diagram showed that CXCL9 was a common DEG between breast cancer brain metastasis and AD.Functional enrichment analysis indicated that CXCL9 was involved in cellular responses to chemokines,negative regulation of immune system processes,negative regulation of vascular morphogenesis,Toll-like receptor signaling pathway,nucleotide oligomerization domain(NOD)-like receptor signaling pathway,and JAK-STAT signaling pathway.Before radiotherapy,patients with cognitive function impairment and normal cognitive function accounted for 61.9%and 38.1%,respectively,with a statistically significant difference in MMSE scores[(24.53±2.19)vs.(28.89±1.36),P＜0.01].Compared with normal cognitive function group,patients with cognitive function impairment had a significantly increased number of brain metastases and significantly lower Karnofsky performance status(KPS)scores and serum CXCL9 levels(P＜0.05).Three months after radiotherapy,patients with cognitive function impairment and normal cognitive function accounted for 47.6%and 52.4%,respectively,with a statistically significant difference in MMSE scores[(25.16±1.98)vs.(28.18±1.08),P＜0.01].Compared with normal cognitive function group,patients with cognitive function impairment had significantly lower CXCL9 levels(P=0.003).In patients with normal cognitive function,CXCL9 levels were remarkably lower after radiotherapy compared to those before radiotherapy(P=0.009).Conclusions Patients with cognitive function impairment had significantly lower CXCL9 levels than those with normal cognitive function,and whole-brain radiotherapy may be related to a certain degree of reduction in CXCL9 levels.

Objective To analyze the stress changes of thoracic vertebra(T)11-sacrum(S)titanium rods in patients with ankylosing spondylitis after vertebral column decancellation(VCD)osteotomy,and provide reference for the selection and improvement of titanium rods before surgery.Methods The original data of the continuous scanning tomographic images of patients with ankylosing spondylitis after VCD osteotomy were imported into Mimics 21.0 in DICOM format,and T11-S vertebrae,screws and titanium rods were respectively reconstructed.They were imported into 3-Matic to establish a preliminary geometric modeling,and then processed with noise removal,paving,smoothing,etc.The improved model was imported into Hypermesh 10 software for grid division,and the material was imported into ANSYS 19.2 to display the finite element model after attribute assignment,Set the boundary and load conditions,and measure the stress value at the connection between the screw and the titanium rod.Results Under neutral position,forward bending,lateral bending,and axial rotation conditions,the titanium rod had the highest stress at the upper vertebrae(T11)and the lowest stress at the top vertebrae(L3);Under the backward extension condition,the titanium rod has the highest stress at the lower end vertebra(L5).Conclusion In the upper and lower vertebrae,it is possible to consider increasing the diameter of the titanium rod,enhancing its hardness,or changing it to a double rod.

Objective To measure the distance between the lateral compression Ⅱ(LC-Ⅱ)screw guide needle and the surrounding important structures around the anterior inferior iliac spine in pelvic fractures and to locate the needle point,so as to provide anatomical reference for clinical nail placement.Methods Totally 40 adult gross specimens of embalming were implanted with LC-Ⅱ screw guide needle under the surveillance of C-arm machine,and the specimens were dissected.The shortest distance between the insertion point and the lateral femoral cutaneous nerve,femoral nerve,femoral artery,femoral vein,anterior superior iliac spine and inguinal ligament was measured.The triangle was constructed between the insertion point,anterior superior iliac spine and inguinal ligament,and the exact location of the entry point was calculated.Results The average distance between the insertion point of the male needle and the femoral vein was(50.67±7.29)mm＞the anterior superior iliac spine(43.83±7.58)mm＞the femoral artery(38.35±6.63)mm＞the femoral nerve(31.17±1.67)mm=the inguinal ligament(28.69±6.59)mm＞the lateral femoral cutaneous nerve(7.98±3.81)mm.The mean distance between the insertion point of the female needle and the anterior superior iliac spine was(45.28±7.07)mm=femoral vein(43.72±6.89)mm＞femoral artery(33.76±6.33)mm＞femoral nerve(25.66±6.46)mm=inguinal ligament(23.22±5.00)mm＞lateral femoral cutaneous nerve(8.97±4.76)mm.The projection distance of the entry point was 31.77 mm for men and 38.41 mm for women.The Angle b was 42.81°for men and 31.71° for women.Conclusion The lateral femoral cutaneous nerve is most vulnerable to injury when LC-Ⅱ screw is inserted,and the risk of injury has nothing to do with sex.The insertion point positioning method a and b made LC-Ⅱ screw placement quickly,safely and accurately,and reduced fluoroscopy time and frequency.

Objective:To investigate the effect and predictive value of plasma apolipoprotein A1(ApoA1)/apoli-poprotein B(ApoB)ratio on early cerebral infarction(CI)after transient ischemic attack(TIA).Methods:A total of 147 TIA patients who were hospitalized in the Neurology or Emergency Department of Affiliated Hospital of North China University of Science and Technology from September 2018 to May 2021 were retrospectively collect-ed.According to presence of cerebral infarction within 7d,they were divided into CI group(n=65)and no CI group(n=82).Immunoturbidimetry was used to detect plasma ApoA1 and ApoB levels,then ApoA1/ApoB ratio was calculated;ROC curve was used to analyze the predictive value of plasma ApoA1/ApoB ratio for early CI after TIA;Logistic regression was used to analyze influencing factors of early CI after TIA.Results:Compared with no CI group,CI group had significantly higher proportions of hyperlipidemia history(52.44％vs.69.23％),stroke history(36.59％vs.55.38％),intracranial artery stenosis(21.95％vs.38.46％)and cerebral ischemia duration≥30min(51.22％vs.73.85％),levels of triglyceride[(1.27±0.48)mmol/L vs.(1.65±0.53)mmol/L]and fast-ing blood glucose[FBG:(5.43±1.52)mmol/L vs.(6.05±1.65)mmol/L](P＜0.05 or＜0.01);significant lower plasma ApoA1 level[(1.35±0.32)g/L vs.(1.07±0.30)g/L]and ApoA1/ApoB ratio[(1.52±0.34)vs.(1.03±0.31)]and significant higher ApoB level[(0.85±0.23)g/L vs.(1.04±0.27)g/L](P＜0.001 all).Sen-sitivity and specificity of plasma ApoA1/ApoB ratio predicting early CI after TIA was 86.15％and 82.93％respec-tively,the area under the curve was 0.884(95％CI 0.821～0.931,P＜0.001)and cutoff value was 1.33.Multi-variate Logistic regression analysis suggested that hyperlipidemia,stroke history,intracranial artery stenosis,FBG＞6.1 mmol/L and cerebral ischemia duration＞30min were independent risk factors for early CI after TIA(OR=1.128～6.613,P＜0.05 or＜0.01),while ApoA1/ApoB ratio＞1.33 was its independent protective factor(OR=0.005,P＜0.001).Conclusion:Plasma ApoA1/ApoB ratio significantly decreases in patients with cerebral infarc-tion after TIA,which is a factor affecting early cerebral infarction after TIA,and it has certain predictive value for it.

Objective To investigate the clinical characteristics and prognosis of pneumococcal meningitis(PM),and drug sensitivity of Streptococcus pneumoniae(SP)isolates in Chinese children.Methods A retrospective analysis was conducted on clinical information,laboratory data,and microbiological data of 160 hospitalized children under 15 years old with PM from January 2019 to December 2020 in 33 tertiary hospitals across the country.Results Among the 160 children with PM,there were 103 males and 57 females.The age ranged from 15 days to 15 years,with 109 cases(68.1% )aged 3 months to under 3 years.SP strains were isolated from 95 cases(59.4% )in cerebrospinal fluid cultures and from 57 cases(35.6% )in blood cultures.The positive rates of SP detection by cerebrospinal fluid metagenomic next-generation sequencing and cerebrospinal fluid SP antigen testing were 40% (35/87)and 27% (21/78),respectively.Fifty-five cases(34.4% )had one or more risk factors for purulent meningitis,113 cases(70.6% )had one or more extra-cranial infectious foci,and 18 cases(11.3% )had underlying diseases.The most common clinical symptoms were fever(147 cases,91.9% ),followed by lethargy(98 cases,61.3% )and vomiting(61 cases,38.1% ).Sixty-nine cases(43.1% )experienced intracranial complications during hospitalization,with subdural effusion and/or empyema being the most common complication[43 cases(26.9% )],followed by hydrocephalus in 24 cases(15.0% ),brain abscess in 23 cases(14.4% ),and cerebral hemorrhage in 8 cases(5.0% ).Subdural effusion and/or empyema and hydrocephalus mainly occurred in children under 1 year old,with rates of 91% (39/43)and 83% (20/24),respectively.SP strains exhibited complete sensitivity to vancomycin(100% ,75/75),linezolid(100% ,56/56),and meropenem(100% ,6/6).High sensitivity rates were also observed for levofloxacin(81% ,22/27),moxifloxacin(82% ,14/17),rifampicin(96% ,25/26),and chloramphenicol(91% ,21/23).However,low sensitivity rates were found for penicillin(16% ,11/68)and clindamycin(6% ,1/17),and SP strains were completely resistant to erythromycin(100% ,31/31).The rates of discharge with cure and improvement were 22.5% (36/160)and 66.2% (106/160),respectively,while 18 cases(11.3% )had adverse outcomes.Conclusions Pediatric PM is more common in children aged 3 months to under 3 years.Intracranial complications are more frequently observed in children under 1 year old.Fever is the most common clinical manifestation of PM,and subdural effusion/emphysema and hydrocephalus are the most frequent complications.Non-culture detection methods for cerebrospinal fluid can improve pathogen detection rates.Adverse outcomes can be noted in more than 10% of PM cases.SP strains are high sensitivity to vancomycin,linezolid,meropenem,levofloxacin,moxifloxacin,rifampicin,and chloramphenicol.[Chinese Journal of Contemporary Pediatrics,2024,26(2):131-138]

Objective To analyze the clinical and serological typing characteristics of invasive Haemophilus influ-enzae(Hin)infection in children.Methods Clinical data of 34 children with invasive Hin infection admitted to Children's Hospital of Shanxi from 2015 to 2021 were analyzed retrospectively.According to clinical diagnosis,they were divided into meningitis infection group and non-meningitis infection group.General data,symptoms,signs,laboratory serological indicators,and Hin serum typing characteristics of children,as well as differences in inflammatory factor level between the two groups were analyzed.Results Among the 34 patients,22 were males and 12 were females,with a male to female ratio of 1.83∶1.Children aged ≤36 months accounted for 82.35％.The levels of procalcitonin(PCT)(23.71[4.10,77.80])ng/mL and C-reactive protein(CRP)(200.00[164.55,200.00])mg/L in children in the meningitis infection group were higher than those in the non-meningitis group(1.08[0.49,6.00]ng/mL,69.46[48.09,125.63]mg/L,respectively),with statistically significant differences(both P＜0.05).The platelet(PLT)count in the non-meningitis group([312.56±186.81]× 109/L)was higher than that in the meningitis group([183.28±165.67]× 109/L),with statistically significant difference(P＜0.05).There was no statistically significant difference in white blood cell(WBC)count and neutrophil(NEUT)percentage between two groups(both P＞0.05).Among the isolated Hin strains,27,2,and 2 strains were type b(Hib),e and f,respectively;3 strains were not typed;serotype a,c and d strains were not found.There was no statistically significant difference in the distribution of typeable Hin strains between the two groups(x2=0.25,P＞0.05).There was no statistically significant difference in the constituent rate of typeable Hin strains between male and fe-male children(67.74％vs 32.26％,x2=1.42,P＞0.05).Conclusion The majority of invasive Hin infection cases are children under 3 years old,and the predominant strain is type b.CRP and PCT levels of infected children in-creased significantly,while PLT is significantly lower than that of non-infected children,which has certain clinical diagnostic value and can provide effective support for early classified diagnosis and anti-infection treatment of inva-sive infectious diseases combined with other clinical testing items.

This study was aimed at creating an engineered strain of Bacillus subtilis for efficient expression of biologically active type 2 toxin B(TcdB2)derived from a highly virulent strain of Clostridium difficile.The TcdB2 gene was cloned from ST1/RT027 strain genome DNA,incorporated into the PHT01 vector,and then transformed into B.subtilis strain WB800N for prokaryotic expression.Cell toxicity assays revealed that the recombinant TcdB2 exhibited cytotoxic effects in various cells.The engineered B.subtilis strain effectively expressed biologically active TcdB2,thus providing a basis for further exploration of the pathogenic mechanisms of highly virulent strains of C.difficile and establishing a foundation for potential vaccine can-didate targets.