Objective To quantitatively assess the association of short-term exposure to polycyclic aromatic hydrocarbons (PAHs) in ambient fine particulate matter (PM2.5) with residents mortality. Methods A time-stratified case-crossover study was conducted from 2020 to 2022 among 10606 non-accidental residents by using the Guangzhou Cause of Death Surveillance System in Conghua District, Guangzhou. Exposure levels of PAHs in PM_2.5 and meteorological data during the study period were obtained from the Center for Disease Control and Prevention in Conghua District and the China Meteorological Administration Land Data Assimilation System (CLDAS-V2.0), respectively. Conditional Poisson regression model was used to estimate the exposure-response association between PAHs and the mortality risk. Results Fluoranthene, chrysene, benzo[k]fluoranthene, benzo[a]pyrene, and indeno[1,2,3-cd]pyrene were significantly associated with an increased risk of mortality. For every one interquartile range increase in exposure levels, the non-accidental mortality risks increased by 8.33% (95% CI: 1.80%, 15.27%), 4.67% (95% CI: 1.86%, 7.57%), 6.07% (95% CI: 2.08%, 10.21%), 4.62% (95% CI: 1.85%, 7.47%), and 4.70% (95% CI: 0.53%, 9.03%), respectively. The estimated non accidental deaths attributable to exposure to fluoranthene, chrysene, benzo[k]fluorine, benzo[a]pyrene and indine[1,2,3-cd]pyrene were 5.91%, 6.08%, 6.51%, 6.46%, and 4.21%, respectively. Conclusions Short-term exposure to PAHs in PM_2.5, including fluoranthene, chrysene, benzo[k]fluoranthene, benzo[a]pyrene and indine[1,2,3-cd]pyrene, was significantly associated with an increased risk of mortality among residents.

Objective Mobile artificial lumbar complex(MALC)which suitable for reconstruction after subtotal lumbar resection in goats was developed,and to test stability of the complex and postoperative lumbar segmental motor function.Methods Eighteen male boer goats aged from 1 to 2 years old(weighted from 35 to 45 kg)were selected and divided into con-trol group,fusion group and non-fusion group,with 6 goats in each group.According to preoperative CT scans and MRI exami-nations of lumbar,the goat MALC was designed and performed by 3D printed for non-fusion group.Operation was performed on three groups respectively,and only vertebral body and disc were exposed in control group.In fusion group,L4 part of vertebral body and the upper and lower complete disc tissues were removed,and the lumbar spine bone plate fixation was performed with titanium mesh bone grafting.In non-fusion group,vertebral body and disc were removed in the same way,and MALC was im-planted.AP and lateral X-rays of lumbar vertebrae in goat were taken at 6 months after surgery,in order to understand whether the plant was dislocated,displaced and fractured.Biomechanical tests were performed on the specimens by mechanical instru-ment to measure range of motion(ROM)of L2,3,L,4,L4,5intervertebral space and the overall ROM of L2-5 lumbar vertebrae.Results MALC of lumbar vertebra was designed by 3D printing,and its component artificial vertebrae and upper and lower ar-tificial end plates were manufactured.The semi-spherical structure was fabricated by precision lathe using high-crosslinked polyethylene material,and the prosthesis was assembled.Postoperative AP and lateral X-rays of lumbar vertebra at 6 months showed the implant position of implant and MALC were good without displacement and dislocation.In vitro biomechanical test of lumbar vertebrae specimens:(1)There were no statistical significance in ROM of lumbar intervertebral space flexion and extension,lateral flexion and rotation on L.4 and L4,5,between non-fusion group and control group(P＞0.05),while ROM of fu-sion group was significantly reduced compared with the other two groups(P＜0.05).There were no significant difference in ROM of L2.3 intervertebral flexion and extension,lateral flexion and rotation between non-fusion group and control group(P＞0.05),while fusion group was significantly increased compared with the other two groups(P＜0.001).(2)There was no signifi-cant difference in overall lumbar ROM of L2-5(P＞0.05).Conclusion The individual MALC could restore intervertebral height of lumbar vertebra while maintaining the stability of lumbar vertebra and re-establishing motor function of lumbar space.

Hydrogen sulfide,as a third gas signal molecule and neurotransmitter,can play a neuroprotective role by anti-oxidative stress,anti-inflammatory response,metabolic inhibition and other mechanisms.It is of great significance for the occurrence and development of neurodegenerative diseases including Alzheimer's disease(AD)and Parkinson's disease(PD)mediated by neuroinflammation.This article reviews the research progress of hydrogen sulfide and neuroinflammation and its mediated neurodegenerative diseases,so as to provide new ideas for the treatment of neurodegenerative diseases.

Confirmed cases of Lyme disease(LD)in Ji'an City,Jiangxi Province and the clinical manifestations and region-al distribution were assessed to provide a basis for timely diagnosis and treatment.In total,133 serum samples were collected from patients with suspected LD in Ji'an Central People's Hospital from December 2021 to August 2022.Serum antibodies a-gainst Borrelia burgdorferi were detected with a two-step testing process.In addition,a specific gene of B.burgdorferi in samples was identified by nested PCR.Sequencing analysis was conducted to confirm the positive samples.Overall,25(18.80％)serum samples were positive for B.burgdorferi nucleic acid and antibodies,which included 20(15.04％)positive for antibodies and 6(4.51％)positive for nucleic acids.The sequences of the 5S-23S rRNA gene spacer of 6 samples were con-sistent with the corresponding sequences of Borrelia yangtzensis and one of the six samples was also positive for antibodies.The 25 positive samples were collected from 9 counties in Ji'an City,with the majority in Jizhou District(44％).All positive patients may experience symptoms related to LD,including joint disorders,neurological disorders,infectious fever,der-matitis,and/or chest pain.The most common symptom was joint disorders(72％).Six cases positive for B.yangtzensis nucleic acids were mainly collected in the Jizhou District,of which four had joint lesions and two had infectious fever.This study confirms the existence of LD in Jiangxi Province,which may be the first confirmation of human infection with B.yan-gtzensis in southern China.Hence,doctors in this region should consider the possibility of LD for cases presenting with related symptoms.Although LD may occur in this region,further investigations and monitoring are warranted.

Investigating the species/biovars,distribution patterns,and genetic correlations of Brucella from sheep in north-west China is critical to reveal the population and epidemiological characteristics of the Brucella melitensis.In this study,con-ventional identification and AMOS-PCR were used to determine the species/biovars of Brucella isolated from 13 regions in northwest China.MLST and MLVA-16 genotyping methods were used to analyze the genetic characteristics of the strains.Con-ventional identification and AMOS-PCR detection revealed that 59 Brucella melitensis were isolated in this study,in-cluding 22 strains from Inner Mongolia,17 strains from Xin-jiang,13 strains from Gansu,and 7 strains from Qinghai,of which 58 strains were B.melitensis biovar 3,and one strain was B.melitensis biovar 1.MLST analysis indicated that 90％(53/59)of B.melitensis were of ST8 sequence type,the dominant epidemic population.The MLVA-11 survey demonstrated that 59 B.melitensis strains clustered into six MLVA-11 genotypes,and 87％of the strains were of MLVA-11 genotype 116.Therefore,the predominant strains in the northwest region were from the Eastern Mediterranean lineage.MLVA-16 divided 59 strains of B.melitensis into 40 gen-otypes,eight of which were shared genotypes.Each genotype was composed of two to seven strains from the same region,thereby indicating that the cases of each shared genotype were outbreaks from a common source of infection.All shared MLVA-16 genotypes comprised strains from the same province,thus indicating apparent regional clustering characteristics of strains in each province.In a genetic comparison between populations and isolated strains from the spleens of sheep,multiple identical MLVA-16 genotypes were found to be composed of strains from different hosts.These findings indicated a transmission path-way from sheep/goats to humans.B.melitensis biovar 3 was the main pathogen causing animal brucellosis in the northwest re-gion,and infected sheep were the main brucellosis infection source in the regional population.The ST8 strains were the domi-nant epidemic population,and the MLVA genotype of strains in each region showed clear regional clustering characteristics.

Objective:To investigate the accuracy of next-generation sequencing technology(NGS)in detecting the polymorphisms of HLA-DRB1,DQB1,DQA1,DRB3,DRB4,DRB5,DPA1 and DPB1 alleles in randomly-selected unrelated healthy individuals from Shenzhen Han population,investigate the potential reason for HLA-DRB1 allele dropout in routine NGS,and establish an internal quality control system.Methods:NGS-based HLA class Ⅱ genotyping was performed on 1 012 samples using the MiSeqDxTM platform.The suspected missed alleles indicated by the quality control software and HLA-DRB1 homozygotes were confirmed by PCR-SSOP or PCR-SBT methods.Results:A total of 139 alleles were detected,including HLA-DRB1(45),DRB3(7),DRB4(5),DRB5(7),DQA1(17),DQB1(21),DPA1(10)and DPB1(27).HLA-DRB 1*09:01(17.09％),15:01(10.72％);DRB3*02:02(25.99％),03:01(10.18％);DRB4*01:03(36.46％);DRB5*01:01(15.42％);DQA1*01:02(20.01％),03:02(17.19％);DQB1*03:01(19.47％),03:03(17.98％),05:02(11.66％),06:01(10.67％);DPA1*02:02(54.45％),01:03(31.18％)and DPB1*05:01(39.13％),02:01(16.90％)alleles were the most common alleles in Shenzhen Han population(frequencies＞10％).There was no statistical difference between the gene frequencies of HLA-DRB1 and DQB1 loci in our study.The HLA Common and Well-Documented Alleles in China(CWD2.4)(x2=12.68,P＞0.05).94 cases of HLA-DRB1 homozygous samples detected by NGS were retested by PCR-SSOP or SBT method,and one case of allele dropout at HLA-DRB1 locus was found.SBT method confirmed that the allele of DRB1*04:03 was missed.The laboratory internal quality control system was established.Two cases of new alleles were detected and named by WHO Nomenclature Committee for Factors of the HLA System.Conclusion:The HLA genotyping results based on NGS showed a significantly lower ambiguity rate.The HLA class Ⅱ alleles exhibit genetic polymorphism in the Han population of unrelated healthy individuals in Shenzhen.The independent method based on NGS in clinical histocompatibility testing has limitations and requires internal quality control strategies to avoid allele-dropout events.

Allyl isothiocyanate (AITC) is a natural product commonly used in food preservation and pharmaceutical applications. Toxoplasmosis, caused by the protozoan pathogen Toxoplasma gondii, is prevalent globally while the impact of AITC on toxoplasmosis is unclear. We explored the effect of AITC on acute toxoplasmosis. We infected C57BL/6 mice with T. gondii type I RH strain following AITC administration. On the 4th day after infection, which corresponds to the initial stage of infection, we collected serum for the determination of inflammatory cytokine levels. The mice serum of the AITC-administered group contained significantly lower levels of granulocyte colony-stimulating factor, interferon-gamma, interleukin (IL)-23 subunit p19, IL-4, IL-6, and monocyte chemoattractant protein-1. The lifespan of the mice in the AITC-administered group was significantly reduced. In vitro experiments showed that AITC promoted the proliferation of intracellular T. gondii accompanied by the inhibition of IL-4, IL-1β, and IL-6 production in RAW264.7 macrophages. Our results showed that AITC facilitated T. gondii infection in the early stage by inhibiting the production of several inflammatory cytokines.

Objective To design a hyperbaric oxygen chamber ambulance to meet the requirements for on-site hyperbaric oxygen treatment and transport of casualties.Methods A hyperbaric oxygen chamber ambulance was formed based on a YJ2080 wheeled armored vehicle,which had the components of a chamber,a gas source,an oxygen source,a control system and a power source.The chamber had a 3-layer composite structure,with a high-strength metal frame in the outer layer,a capsule made of polyurethane material bound with nylon pressure-resistant tape in the inner layer and a layer of thermal insulation material filled between the chamber and the vehicle;the gas source was composed of the oil-free air compressor,gas cylinder and pressure reducer;the oxygen source was made up of the 20 L oxygen generator,oxygen booster pump and 40 L oxygen cylinder;the control system involved in an EX2N-100HA series touch screen programmable logic controller(PLC)all-in-one(AIO);an ACD-15.0DR/48-H generator system was used as the power source.Results The hyperbaric oxygen chamber ambulance could stably control the chamber pressure when the therapeutic pressure was set as 1.3,1.6 and 1.8 ATA(1 ATA=0.1 MPa),the volume fraction of oxygen in the chamber could be limited within the required range under the low oxygen volume fraction mode and high oxygen volume fraction mode,and the emergency decompression time could be restrained within 60 s.Conclusion The hyperbaric oxygen chamber ambulance behaves well in maneuverability,and can be used for on-site hyperbaric oxygen treatment and transport of casualties.[Chinese Medical Equipment Journal,2024,45(10):25-30]

Allyl isothiocyanate (AITC) is a natural product commonly used in food preservation and pharmaceutical applications. Toxoplasmosis, caused by the protozoan pathogen Toxoplasma gondii, is prevalent globally while the impact of AITC on toxoplasmosis is unclear. We explored the effect of AITC on acute toxoplasmosis. We infected C57BL/6 mice with T. gondii type I RH strain following AITC administration. On the 4th day after infection, which corresponds to the initial stage of infection, we collected serum for the determination of inflammatory cytokine levels. The mice serum of the AITC-administered group contained significantly lower levels of granulocyte colony-stimulating factor, interferon-gamma, interleukin (IL)-23 subunit p19, IL-4, IL-6, and monocyte chemoattractant protein-1. The lifespan of the mice in the AITC-administered group was significantly reduced. In vitro experiments showed that AITC promoted the proliferation of intracellular T. gondii accompanied by the inhibition of IL-4, IL-1β, and IL-6 production in RAW264.7 macrophages. Our results showed that AITC facilitated T. gondii infection in the early stage by inhibiting the production of several inflammatory cytokines.

Allyl isothiocyanate (AITC) is a natural product commonly used in food preservation and pharmaceutical applications. Toxoplasmosis, caused by the protozoan pathogen Toxoplasma gondii, is prevalent globally while the impact of AITC on toxoplasmosis is unclear. We explored the effect of AITC on acute toxoplasmosis. We infected C57BL/6 mice with T. gondii type I RH strain following AITC administration. On the 4th day after infection, which corresponds to the initial stage of infection, we collected serum for the determination of inflammatory cytokine levels. The mice serum of the AITC-administered group contained significantly lower levels of granulocyte colony-stimulating factor, interferon-gamma, interleukin (IL)-23 subunit p19, IL-4, IL-6, and monocyte chemoattractant protein-1. The lifespan of the mice in the AITC-administered group was significantly reduced. In vitro experiments showed that AITC promoted the proliferation of intracellular T. gondii accompanied by the inhibition of IL-4, IL-1β, and IL-6 production in RAW264.7 macrophages. Our results showed that AITC facilitated T. gondii infection in the early stage by inhibiting the production of several inflammatory cytokines.