Background Bacteria are the most diverse and widely sourced microorganisms in the indoor air of subway stations, where pathogenic bacteria can spread through the air, leading to increased health risks. Objective To understand the status and distribution characteristics of indoor air bacterial pollution in subway stations and compartments in a city of Central South China, and to provide a scientific basis for formulating intervention measures to address indoor air bacteria pollution in subways. Methods Three subway stations and the compartments of trains parking there in a city in Central South China were selected according to passenger flow for synchronous air sampling and monitoring. Temperature, humidity, wind speed, carbon dioxide (CO₂), fine particulate matter (PM_2.5), and inhalable particulate matter (PM₁₀) were measured by direct reading method. In accordance with the requirements of Examination methods for public places-Part 3: Airborne microorganisms (GB/T 18204.3-2013), air samples were collected at a flow rate of 28.3 L·min⁻¹, and total bacterial count was estimated. Bacterial microbial species were identified with a mass spectrometer and pathogenic bacteria were distinguished from non-pathogenic bacteria according to the Catalogue of pathogenic microorganisms transmitted to human beings issued by National Health Commission. Kruskal-Wallis H test was used to compare the subway hygiene indicators in different regions and time periods, and Bonferroni test was used for pairwise comparison. Spearman correlation test was used to evaluate the correlation between CO₂ concentration and total bacterial count. Results The pass rates were 100.0% for airborne total bacteria count, PM_2.5, and PM₁₀ in the subway stations and train compartments, 94.4% for temperature and wind speed, 98.6% for CO₂, but 0% for humidity. The overall median (P₂₅, P₇₅) total bacteria count was 177 (138,262) CFU·m⁻³. Specifically, the total bacteria count was higher in station halls than in platforms, and higher during morning peak hours than during evening peak hours (P<0.05). A total of 874 strains and 82 species were identified by automatic microbial mass spectrometry. The results of identification were all over 9 points, and the predominant bacteria in the air were Micrococcus luteus (52.2%) and Staphylococcus hominis (9.8%). Three pathogens, Acinetobacter baumannii (0.3%), Corynebacterium striatum (0.1%), and Staphylococcus epidermidis bacilli (2.2%) were detected in 23 samples (2.6%), and the associated locations were mainly distributed in train compartments during evening rush hours. Conclusion The total bacteria count in indoor air varies by monitoring sites of subway stations and time periods, and there is a risk of opportunistic bacterial infection. Attention should be paid to cleaning and disinfection during peak passenger flow hours in all areas.

Objective:A nested-PCR assay is developed to detect and identify the genomic DNA of Brucella vaccine A19 strain. Methods:The whole genomic sequences of Brucella vaccine A19 strain and other Brucella spp. strains were compared and analyzed. The primers were designed by nucleotide difference sites. The nested-PCR assay was established to detect and identify Brucella vaccine A19 strain. The genomic DNA of Brucella vaccine A19 strain was extracted and diluted. The diluted template DNA was tested for sensitivity of using nested-PCR assay. And the specificity of nested-PCR assay was tested for the genomic DNA of other Brucella spp. strains and non- Brucella spp. strains. Results:The minimum detection limit of the nested-PCR assay was 3.43 fg. The nested-PCR assay established for amplification of Brucella vaccine A19 strain showed 246 bp electrophoresis bands, while other Brucella spp. strains showed 314 bp electrophoresis bands, and non- Brucella spp. strains did not produce electrophoresis bands. Conclusions:The nested-PCR assay established has the characteristics of high sensitivity and specificity. It can be detected when there is one copy of Brucella vaccine A19 strain genomic DNA in the reaction system. This method is particularly suitable for the detection and identification of trace genomic DNA of Brucella vaccine A19 strain in sample.

Objective:To establish a quantitative real-time PCR detection system for Brucella S2 vaccine strain. Methods:Based on the differences in the entire genome sequence between Brucella S2 vaccine strain and other reference strains of Brucella, primers and probes were designed to establish a quantitative real-time PCR detection system for Brucella S2 vaccine strain. The DNA of 22 reference strains of Brucella and 8 non- Brucella control strains were obtained from the National Institute for Infectious Disease Control and Prevention of the Chinese Center for Disease Control and Prevention. At the same time, environmental samples were obtained from the brucellosis vaccine manufacturers, and bacterial DNA from environmental samples was extracted using a blood/tissue genomic DNA extraction kit. The obtained DNA was pre-amplified by conventional PCR, and then subjected to quantitative real-time PCR secondary amplification (nested fluorescence quantitative PCR) using the amplified PCR product as a template. The specific fluorescence curve and corresponding number of cycles (Ct value) were observed, and the sensitivity was tested. Results:The quantitative real-time PCR detection system established did not detect specific fluorescence curves (without Ct values) for 21 reference strains of Brucella and 8 non- Brucella control strains, except for S2 vaccine strains. The established detection system had a minimum detection limit of 4.34 fg (genomic DNA) for detecting the DNA of Brucella S2 vaccine strain; DNA of Brucella S2 vaccine strain was detected in 3 of the 14 environmental samples collected. Conclusion:The quantitative real-time PCR detection system established can detect Brucella S2 vaccine strain in samples, with good sensitivity and specificity.

Objective: To analyze the etiological characteristics of an outbreak of Campylobacter foodborne disease in a middle school in Suzhou City, so as to provide insights into the identification of pathogenic factors of Campylobacter foodborne disease outbreaks. Methods: Eighteen anal swabs from patients, 10 anal swabs from canteen workers, 43 food samples, 2 drinking water samples, 2 food original material samples and 31 environmental samples were collected, and the pathogens were rapidly screened using the gastrointestinal infection detection strip. The pathogens were isolated and cultured using the double-pore filtration membrane method, and cluster analysis of bacterial isolates was performed using pulsed field gel electrophoresis ( PFGE ). In addition, the susceptibility of Campylobacter isolates to antibiotics was tested using the Campylobacter agar dilution method. Results: A total of 63 cases with Campylobacter infections were reported, and the major clinical symptoms included diarrhea ( 51 cases, 80.95% ) and fever ( 39 cases, 61.90% ), while no inpatients or deaths were found. Twelve Campylobacter-positive samples were detected, including 11 anal swabs sampled from patients and one food original material sample. Among the 11 positive anal swabs, there were 10 samples positive for Campylobacter jejuni and one sample positive for C. coli, and of the one positive food original material, C. coli was identified. PFGE analysis showed that 10 C. jejuni isolates of had 100.0% homology, and these 10 isolates were 100.0% resistant to naphthyridic acid, ciprofloxacin and tetracycline, appearing multidrug resistance. Conclusions This is an outbreak of foodborne disease caused by C. jejuni infections. Gastrointestinal infection detection strips, double-pore filtration membrane and PFGE typing are rapid and accurate to identify pathogenic factors.

A case of Usher syndrome with methylmalonic acidemia and homocysteine is reported. The patient was a two-month-old and small for gestational age male infant hospitalized for "feeding difficulties" during the neonatal period. The baby boy presented hypotonia, microcephaly, and hearing loss after birth. Genetic test found compound heterozygous mutations of c.482G>A and c.567dup in MMACHC, and both were pathogenic mutations inherited from his parents. Moreover, the patient also had compound heterozygous variants at c.2802T>G and c.14017T>C of USH2A gene. The former was suspected to be pathogenic, and the latter was of unknown clinical significance. Both were from the parents. Usher syndrome and methylmalonic acidemia with homocysteine were clinically diagnosed. Followed up to the age of two, the child was found with moderate mental retardation, while the physical development was comparable to that of the same age group.

Objective:To introduce our experience on dealing with the internal carotid artery (ICA) during the resection of lateral skull base tumors, and to explore the reference values for using radiological findings to make a rational surgical plan.Methods:A retrospective study of patients who underwent resection of lateral skull base tumors involving ICA at Peking Union Medical College Hospital from May 2015 to May 2021 was conducted. The demographic information, preoperative examinations, diagnosis, surgical details and follow-ups were collected. A total of 41 patients were enrolled [24 (58.5%] females, 17 (41.5%) males], with an average age of 47.9 years. According to the preoperative imaging findings, the relationships between the tumors and ICA were divided into four types: adjacency, compression, invasion and ICA aneurysm.Results:The ICA was preserved in 32 (78.0%, 32/41) cases and was reconstructed in nine (22.0%, 9/41) cases. All the 27 (65.9%, 27/41) tumors adjacent to ICA were successfully separated from the artery. Among the 11 tumors compressing the ICA, six were resected with the involved ICA segment and vascular reconstruction was conducted. One (2.4%, 1/41) tumor invading ICA and two (4.9%, 2/41) ICA aneurysms required revascularization. The mean follow-up time was (26.1±2.9) months. There was no recurrence, except one case of adenoid cystic carcinoma which had brain metastases one year after surgery.Conclusions:According to the preoperative imaging, lateral skull base tumors adjacent to ICA can be detached from the vascular surface. Separation should be attempted first for tumors compressing ICA, and revascularization should be followed if separation failed. Vascular reconstruction is usually needed in the removal of tumors invading ICA and ICA aneurysms. Preoperative radiology can provide good references for planning a surgery for lateral skull base tumors.

Here,we reported a case of term infant with unilateral congenital microphthalmia (CM).Physical examination conducted on 2 d after birth showed that the left eye was barely open and the eye socket was deeper than the right.Meanwhile,the cornea of the left eye was not completely exposed and the light reflex could not be elicited.Ophthalmology consultation,ultrasound and CT scan were conducted,and CM was finally diagnosed since the infant was found to have a small eyeball and shortened axial length,accompanying by pathological changes in the lens,vitreous body and retina.This case suggested that detailed physical examination should be carried out,especially for the eyes,including orbit and eyelid,presence or absence of secretion or concealed eyeball,together with medical imaging techniques technology,to ensure an early detection and diagnosis of CM in neonates.

Objective To survey the distribution pattern and subject domain knowledge of the literatures about ventilator-associated pneumonia (VAP). Methods Literatures about VAP published until December 2017 were identified in SinoMed database for statistics and analysis. The information of author, organization and province was extracted by BICOMS software for generating co-occurrence matrix, at the same time, the topic words were cluster analyzed by Gcluto software to generate topical visual surface maps and visualization matrices, and the current research hotspots were analyzed. NetDraw from Ucinet 6.0 software was used to arrange the relationship among topic words according to the centrality, and the social network diagrams of authors, authors' provinces and institutions were draw to analyze the current status of VAP research cooperation. Results 4 851 VAP-related literatures were retrieved preliminarily, and 43 were excluded from abstracts, news reports, information and missing literatures. Finally, a total of 4 808 articles were enrolled in the visual analysis. From 2001 to 2004, the number of VAP-related literatures published was less than 10. Since 2009, the number of VAP documents had increased steadily, from 2010 to 2017, the peak period of publications reached 91.7% (4 411/4 808). According to the analysis of the amount of publications, the top three of 34 provincial administrative regions that published VAP-related literature in China were Guangdong Province (n = 628), Jiangsu Province (n = 478) and Zhejiang Province (n = 404), the number of hospitals issued by the First Affiliated Hospital of Chongqing Medical University was the largest (n = 20); there was only one journal with more than 100 articles, and there were 154 journals with only one article, accounting for 34.8% of the total number of journals. A total of 9 921 authors participated in the VAP-related literature writing, the number of high-yielding authors was not large, and the institution could not establish an effective social network diagram, suggesting that communication and cooperation should be strengthened in hospitals and outside hospitals. The results of the topic words social network analysis showed that the VAP research field was centered around the core of "mechanical ventilation", "intensive care unit (ICU)", "risk factor analysis", "nursing", "etiological analysis", "preventive measures" and "pathogens". The current research hotspots were at the edge of the network map, such as "drug sensitivity analysis", "Acinetobacter baumannii", "bronohoalveolar lavage (BAL)" and "acute exacerbation of chronic obstructive pulmonary disease (AECOPD)". By clustering 80 high-frequency topic words, at present, VAP research hotspots were mainly focus on five topics: obstructive pulmonary disease, especially in acute exacerbation, was prone to VAP; concerned about newborns and children's VAP; types, drug resistance and selection of antimicrobial agents for VAP pathogens in ICU; clinical efficacy and prognosis of VAP through preventive measures, pulmonary supportive care and comprehensive care interventions; oral care and airway management during mechanical ventilation was also the key aspect of the treatment of VAP. Conclusions In recent years, the academics had attached great importance to the study of VAP, the number of publications had reached a historical peak, and the research direction was diverse. However, it was necessary to strengthen cooperation among research institutes, collect and count epidemiological data, improve and expand the research quality and scale of clinical diagnosis, nurse, prevention, pathogen distribution and drug resistance analysis.

In this study, we established a rapid and efficient HPLC method to determine the accumulation of Huperzine A and Huperzine B in the fermentation broth of endophytic fungus Colletotrichum gloesporioides from Huperzia serrate. The chloroform extracts of fermentation broth were dissolved in methanol and filtered before injection for HPLC analysis. The analysis was performed on an Agilent Eclipse plus-C18 column (250 mm×4.6 mm, 5 μm) by isocratic elution. The mobile phase was 0.015 mol/L ammonium acetate-methanol (70:30, V/V), the flow rate was 1 mL/min and the detection wavelength was set at 308 nm. Huperzine A and Huperzine B could be well separated within 25 min. Good linearity of Huperzine A was found in the range of 1.50-48.00 μg/mL (r=0.999 5), and that of huperzine B was in 0.25-7.50 μg/mL (r=0.999 7). The average recoveries of Huperzine A and Huperzine B were 106.83% and 108.06%, respectively (RSD=3.34%, 3.60%). The results demonstrate that this method can detect the content of huperzine A and huperzine B in fermentation broth simply, rapidly, accurately and in good reproducibility. Under the optimized conditions, the accumulated content of huperzine A and huperzine B were measured from the sixth to the fifteenth day. Huperzine A and Huperzine B reached the highest (12.417 0 μg/mL and 4.660 3 μg/mL, respectively) at the fourteenth and eighth days. The analysis methodology could contribute to the future study of huperzine A and huperzine B biosynthesis in C. gloeosporioides, consequently facilitate the development of new drug resources.

Objective: To compare the clinical efficacy and safety of bortezomib, cyclophosphamide, dexamethasone (VCD) regimen and bortezomib dexamethasone (VD) regimen in the treatment of the patients with newly diagnosed multiple myeloma (NDMM). Methods: The clinical data of 73 patients with NDMM in Shanxi Dayi Hospital from January 2013 to January 2016 were retrospectively analyzed. According to the chemotherapy regimen, the patients were divided into VCD group (41 cases) and VD group (32 cases). The efficacy and adverse reactions of the two groups were evaluated. Results: The overall response rate of VCD group and VD group was 80.5% (33/41) and 78.1% (25/32) respectively, and the difference was not statistically significant (χ ²= 0.061, P= 0.804); and complete remission (CR) rate was 36.6% (15/41) and 15.6% (5/32) respectively, and the difference was statistically significant (χ ²= 3.970, P= 0.046); the median progression-free survival (PFS) was 27 months and 24 months respectively, and the median overall survival (OS) was 35 months and 33 months respectively, and the differences were not statistically significant (all P > 0.05). Most adverse reactions occurred in grade 1-2, in which peripheral polyneuropathy and thrombocytopenia were the most common. Peripheral neuritis was the most common finding among the adverse reactions of grade 3. The incidence of adverse reactions in both groups was not statistically significant (P > 0.05). Conclusions VCD and VD regimen could be recommended as a better induction therapy for NDMM patients. Compared with VD scheme, VCD scheme has a higher CR rate.