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.

It has been revealed that hypoxia is dynamic in hypertrophic scars; therefore, we considered that it may have different effects on hypoxia-inducible factor-1α (HIF-1α) and p53 expression. Herein, we aimed to confirm the presence of a teeterboard-like conversion between HIF-1α and p53, which is correlated with scar formation and regression. Thus, we obtained samples of normal skin and hypertrophic scars to identify the differences in HIF-1α and autophagy using immunohistochemistry and transmission electron microscopy. In addition, we used moderate hypoxia in vitro to simulate the proliferative scar, and silenced HIF-1α or p53 gene expression or triggered overexpression to investigate the changes of HIF-1α and p53 expression, autophagy, apoptosis, and cell proliferation under this condition. HIF-1α, p53, and autophagy-related proteins were assayed using western blotting and immunofluorescence, whereas apoptosis was detected using flow cytometry analysis, and cell proliferation was detected using cell counting kit-8 (CCK-8) and 5-bromo-2'-deoxyuridine (BrdU) staining. Furthermore, immunoprecipitation was performed to verify the binding of HIF-1α and p53 to transcription cofactor p300. Our results demonstrated that, in scar tissue, HIF-1α expression increased in parallel with autophagosome formation. Under hypoxia, HIF-1α expression and autophagy were upregulated, whereas p53 expression and apoptosis were downregulated in vitro. HIF-1α knockdown downregulated autophagy, proliferation, and p300-bound HIF-1α, and upregulated p53 expression, apoptosis, and p300-bound p53. Meanwhile, p53 knockdown induced the opposite effects and enhanced HIF-1α, whereas p53 overexpression resulted in the same effects and reduced HIF-1α. Our results suggest a teeterboard-like conversion between HIF-1α and p53, which is linked with scar hyperplasia and regression.
Apoptosis ; Autophagy ; Cell Hypoxia ; Fibroblasts/metabolism* ; Humans ; Hypoxia-Inducible Factor 1, alpha Subunit/metabolism* ; Tumor Suppressor Protein p53/metabolism*

Objective:To evaluate the activity of iduronate-2-sulfatase (IDS) in fetal villi and peripheral blood plasma of pregnant women at high risk of mucopolysaccharidosis type Ⅱ (MPS Ⅱ), and to discuss the application of gene analysis in prenatal diagnosis of MPS Ⅱ.Methods:The enzymatic testing and gene analysis results of 23 pregnant women at high risk of MPS Ⅱ, who underwent prenatal diagnosis in Guangzhou Women and Children′s Medical Center from February 2013 to December 2020, were analyzed retrospectively.The IDS activity in fetal villi (30 cases) and plasma (28 cases) was detected by artificial substrate fluorescence.The IDS activity in fetal villi (28 cases) and plasma (34 cases) of normal pregnant women was taken as control.Meanwhile, the fetal villi of both pregnant women at high risk of MPS Ⅱ and normal pregnant women were also analyzed by gene testing and for fetal sex identification.Data were compared between groups by the independent samples t test. Results:The normal reference values of the IDS activity in fetal villi and plasma of normal pregnant women were(71.2±23.4) nmol/(mg·4 h) and (611.1±114.5) nmol/(mL·4 h), respectively.Among the 30 cases of high-risk fetal villi, the IDS activity in fetal villi of 8 affected male fetuses was (1.7±0.3) nmol/(mg·4 h), which was significantly lower than that of 11 unaffected male fetuses (83.2±6.3) nmol/(mg·4 h) and that of 9 non-carrier female fetuses (80.0±7.5) nmol/(mg·4 h) ( t=10.8, 8.8; all P<0.01). Meanwhile, the IDS activity was measured in the maternal peripheral plasma of 28 pregnant women at high risk of MPS Ⅱ.Among them, the IDS activity in 8 affected male fetuses was(225.4±20.5) nmol/(mL·4 h), which was significantly lower than that in non-affected male fetuses[(451.0±15.1) nmol/(mL·4 h)] and that in non-carrier female fetuses[(467.7±45.3)nmol/(mL·4 h)]. Eight known pathogenic mutations were found in 30 cases at high risk of MPS Ⅱ of fetal villi, and the mutation types were c. 1048A>C, c.212G>A, c.514C>T, c.257C>T, c.425C>T, and c. 998C>T.Of the 8 cases, 6 affected male fetuses had significantly reduced IDS activities, and the other 2 female carriers had normal IDS enzyme activities. Conclusions:The IDS activity in fetal villi and peripheral plasma of pregnant woman is consistent with the gene analysis results.The IDS activity has an important reference value for the prenatal diagnosis of MPS Ⅱ in the first trimester.When no genetic mutations are found in the probands or the pathogenicity of the new mutation remains unclear, the IDS activity in fetal villi can be detected separately for the prenatal diagnosis of MPS Ⅱ.

Objective:To investigate the effect of cyclin D1 (CCND1) negatively regulated by miRNA-541 (miR-541-5p) on the proliferation and migration of colon cancer cells as well as its related mechanism.Methods:Expression levels of miR-541-5p in colon cancer cell lines HT29, SW480, SW620, HCT116 and enterocyte line HIEC of the normal people as well as cancer tissues and pericarcinomatous normal tissues of 112 patients undergoing the colon cancer surgery from the First Affiliated Hospital of Hebei North University between April 2017 and March 2020 were detected by using quantitative real-time polymerase chain reaction(qRT-PCR). The potential target gene of miR-541-5p was predicted by using TargetScan, and was verified by using dual luciferase reporter gene assay, qRT-PCR and Western blot. Expression level of CCND1 was detected in colon cancer cell lines and tissues. Cells with the lowest expression level of miR-541-5p were divided into miR-NC group (the transfected control plasmid), miR-541-5p group (the transfected miR-541-5p mimics), miR-541-5p+CCND1 group (the co-transfected miR-541-5p mimics and CCND1). Effect of miR-541-5p and CCND1 on proliferation and migration ability of colon cancer cells was detected by using cell counting kit-8 (CCK8) and Transwell method. The xenograft model of colon cancer in nude mice was constructed to observe the effect of miR-541-5p on tumor growth.Results:The relative expression level of miR-541-5p in colon cancer tissues was lower than that in pericarcinomatous normal tissues (0.45±0.06 vs. 1.00±0.12, t = 43.385, P < 0.01). The relative expression level of miR-541-5p was 0.46±0.03, 0.67±0.04, 0.57±0.06, 0.17±0.02, 1.00±0.15, respectively in colon cancer cell lines HT29, SW480, SW620, HCT116 and enterocyte line HIEC of the normal people, and the difference was statistiacally significant ( F = 5.621, P < 0.01); the relative expression level of miR-541-5p in all colon cancer cell lines was lower than that in enterocyte line HIEC of the normal people. HCT116 cells were selected to make the subsequent experiments. The predicted results of TargetScan showed that 3'UTR of CCND1 might have sites complementary to those of miR-541-5p. Dual luciferase reporter gene assay showed that CCND1 was the target gene of miR-541-5p, and miR-541-5p negatively regulated the expression of CCND1. CCK-8 method showed that cell proliferation rate of HCT116 was (2.00±0.16)%, (0.89±0.08)%, (2.56±0.23)%, respectively in miR-NC group, miR-541-5p group, miR-541-5p+CCND1 group, and the difference was statistically significant ( F = 6.715, P < 0.01); among HCT116 cells with the overexpression of miR-541-5p, the transfected CCND1 chould reverse the inhibitory effect of miR-541-5p on cell proliferation. Transwell results showed that the overexpression of miR-541-5p inhibited the cell migration ability of HCT116, while the co-transfection of miR-541-5p mimics and CCND1 could reverse the inhibitory effect. In the colon cancer nude mice xenograft model, the tumor mass and size of nude mice in miR-541-5p group was decreased compared with that in the control group (all P < 0.05). Conclusions:miR-541-5p inhibits cell proliferation and migration of colon cancer cells via negatively regulating CCND1, and inhibits tumor growth in xenograft model of colon cancer in nude mice, thereby acting as a tumor suppressor in colon cancer.

Objectives:To explore the GAA varient spectrum and the genotype-phenotype correlations in patients with glycogen storage disease type Ⅱ (Pompe disease, PD), as well as to estimate the disease incidence based on carrier rate of GAA varients in Guangzhou population.Methods:A total of 57 PD cases were retrospectively enrolled at Guangzhou Women and Children′s Medical Center from January 1, 2010 to May 31, 2020. All patients presented symptoms before the age of 18 years. Each diagnosis was further confirmed by GAA enzyme activity and GAA variants. The carrier rate of GAA varients was calculated based on variants detected by whole exon sequencing among 2 395 healthy children in Guangzhou.Results:Among the 57 PD patients (including male 26, female 31),twenty-eight patients with infantile onset PD (IOPD) presented with progressive general muscle weakness and cardiomyopathy. The mean ages of symptom onset and diagnosis were (2.5±1.4) and (5.0±3.0) months, respectively. Twenty-six cases died in the first year after birth.Twenty-three patients with late onset PD (LOPD) presented with progressive muscle weakness. Seven of them had respiratory failure at diagnosis. The mean ages of symptom onset and diagnosis were (12.0±5.0) and (17.0±7.5) years, respectively. Six children with atypical IOPD showed motor delay, muscle weakness and cardiomyopathy. Their diagnosis was confirmed at 2.5-7.0 years of age. Among the 57 patients, 47 different variants were identified in the GAA gene. Three variants: c.797C>T, c.1109G>A and c.1757C>T were novel. c.1935C>A (25/114, 21.9%) and c.2238G>C (15/114, 13.2%) were the most common variants, detected in 57.1% of IOPD and 65.2% (15/23) of LOPD patients, respectively. Among the 28 IOPD patients, 26 cases (92.9%) carried at least one missense variant which indicated positive cross-reactive immunologic material (CRIM). The carrier rate of pathogenic variants in GAA gene among healthy children was 24/2 395. The estimated incidence of PD in this population is about 1/40 000. The frequencies of pseudodeficiency variants c.1726G>A and c.2065G>A homozygotes were 26.3% (15/57) and 35.1% (20/57) in PD patients, which were significantly higher than those (1.7% (40/2 395) and 3.9% (94/2 395)) in healthy children (χ2=151.2, 121.9; both P<0.01). Conclusions:PD presents as a spectrum, some as atypical IOPD. The c.1935C>A and c.2238G>C are common variants, correlated with IOPD and LOPD respectively. The c.796C>T and c.1082C>T are usually found in atypical IOPD. The majority of IOPD patients is predicted to be CRIM positive. The estimated incidence of PD is about 1/40 000.

Objective: To investigate the clinical features, diagnosis, occurrence sequence and clonal origin of chronic lymphocytic leukemia complicated with multiple myeloma. Methods: The diagnosis and treatment of one patient with multiple myeloma and chronic lymphocytic leukemia who was admitted to the First Hospital of Jilin University in May 2018 was retrospectively analyzed, and the related literatures were reviewed. Results: This patient began with lumbosacral pain, and he was diagnosed as chronic lymphocytic leukemia complicated with multiple myeloma after bone marrow aspiration, flow cytometry, and blood and urine immunofixation electrophoresis. It is recommended that Rd (lenalidomide + dexamethasone) or MPV (melphalan + prednisone + bortezomib) regimen, but the patient did not receive chemotherapy and died of infectious diarrhea 1 month later. Conclusions The occurrence of multiple myeloma and chronic lymphoblastic leukemia may originate from the same clone or different new clone. It is very rare that multiple myeloma and chronic lymphoblastic leukemia can co-occur. Therapeutic options tend to be more aggressive multiple myeloma-based regimen.

Objective:To investigate the mechanisms of effects of high fat and high fructose diet on rat aging.Methods:Adult male SD rats were divided into normal diet(ND) group and high fat and high fructose diet(HFHFD) group. After treatment for 48 weeks, these rats were sacrificed and the blood, liver, and brain tissues were collected. Serum triglyceride(TG), total cholesterol(TC), low density lipoprotein-cholesterol(LDL-C), high density lipoprotein-cholesterol(HDL-C) levels were determined by automatic biochemical analyzer. The serum levels of interluekin-2(IL-2), IL-6, and advanced glycation end products(AGEs) were measured using enzyme linked immunosorbent assay. The expressions of p16, p21, and p53 genes in the liver and brain tissues were detected by real-time quantitative PCR and western blot.Results:After 48 weeks treatment, there were significant differences in body weight and fasting plasma glucose between two groups. Serum TG, TC, and LDL-C in HFHFD group were significantly higher than those in the ND group( P<0.05), with an increase trend in HDL-C but without statistical difference. Compared with ND group, the level of IL-2 in HFHFD group was significantly decreased while the levels of IL-6 and AGEs were significantly increased(all P<0.05). The levels of p16 and p21 mRNA expressions as well as p53 and p21 protein expressions in liver and brain in HFHFD group were markedly increased compared with ND group(all P<0.05). Conclusion:Long-term high fat and high fructose diets accelerate the aging process of rats, which may be related to the damage of the immune system and the changes of cell senescence related gene expressions in liver and brain tissues.

Objective: To study the effects of resistant dextrin (RD) on liver fat deposition in high-fat diet-fed (HFD) mice, and to further explore whether it can regulate the AMPK signaling pathway. Methods: Thirty-six 4-week-old male C57BL/6 mice were randomly divided into three groups: normal control group (chow), high-fat diet group (HFD), and high-fat diet+ resistant dextrin group (HFD+ RD, 10 g·kg^-1·d^-1). After 12 weeks of intervention, the liver tissues and serum samples were collected. Serum triglyceride (TG), total cholesterol (TC), low-density lipoprotein-cholesterol (LDL-C), high-density lipoprotein-cholesterol (HDL-C), aspartate aminotransferase (AST), alanine transaminase (ALT) levels and liver TG were measured. Liver tissue HE and oil red O staining were performed to observe hepatocyte steatosis and liver fat deposition. Quantitative real-time PCR was performed to detect the relative expression of fatty acid synthesis related genes SREBP1, ACC, SCD1 in the liver tissue, and Western blot was performed to detect relative protein levels of pAMPK, SREBP1, Fasn, and ACC in the liver. Results: Compared with chow group, the body weight gain, fasting blood glucose (FBG), serum TC, LDL-C, HDL-C, and ALT levels were increased in HFD group (P<0.01), and serum AST level was also increased (P<0.05). Moreover, liver oil red O staining revealed that liver fat deposition was much more obvious in HFD group than that in chow group, and liver TG was also increased in HFD group (P<0.01). The mRNA levels of SREBP1 and ACC were increased in HFD group compared with that in chow group, and the protein level of pAMPK was reduced in HFD group (P<0.05). As compared with HFD group, the body weight gain, serum TG, TC, LDL-C, HDL-C and ALT levels were significantly reduced in RD group (P<0.01), and FBG level was also reduced (P<0.05). Moreover, RD treatment alleviated liver fat deposition and TG accumulation (P<0.01). The mRNA levels of SREBP1, ACC, and SCD1 were all reduced in RD group compared with HFD group. The protein level of pAMPK was increased, and the expression of Fasn was reduced with RD treatment (P<0.01). Conclusion Resistant dextrin improves liver fat deposition and activates the AMPK signaling pathway in HFD-fed mice.

Objective To compare the regulating effect of electrically stimulating different parts of the auri-cle on the cardiac vagus nerve in rats, and to explore the basic neural mechanism. Methods The tragus, concha auriculae and helix of 24 male Sprague-Dawley rats were stimulated at different intensities ( 0-16 mA) and with differ-ent durations ( 0-15 min) and any changes in the heart rate were observed. One week later, the rats were randomized into a tragus injection group, a concha auriculae injection group, a helix injection group and a control group, each of 6. The rats of the first three groups were injected with 2 μL of cholera toxin subunit B conjugate AF555 ( CTB-AF555) at the right auricle, while the control group was injected with the same amount of aseptic phosphate-buffered saline at the right tragus. Five days later, all of the rats were sacrificed and their right superior and inferior ganglia and the whole bulbus medullae were resected to observe the fluorescent labeling sites. Results The rats'heart rate declined with longer and more intense stimulation of the tragus or concha auriculae, but not with stimulation of the he-lix. With stimulation of the same duration, a significant decrease was observed in the heart rate when the tragus and concha auriculae were stimulated at 10, 12, 14 or 16 mA compared with when the helix was stimulated at the same intensities. The heart rate when the concha auriculae was stimulated at 12 mA was significantly slower than when the tragus was stimulated at the same intensity. At identical stimulus intensities, the heart rate slowed significantly more when the tragus was stimulated for 6 to 15 minutes and the concha auriculae for 4 to 15 minutes compared with stimu-lating the helix for the same length of time. And compared with stimulating the tragus for 6 to 10 minutes, the heart rate decreased significantly more when the concha auriculae was stimulated for the same length of time. All of the rats in the tragus and concha auriculae injection groups displayed nerve tracer in their superior and inferior ganglia. In the tragus injection group, CTB-AF555 was observed in the nucleus tractus solitarius ( NTS) of 3 of the 6 rats. In the concha auriculae injection group it was observed in 4 of the 6. In the helix injection group, CTB-AF555 was observed in the nucleus of the spinal tract in 5 of the 6 rats, but no nerve tracer was found in their superior or inferior ganglia or in the NTS. Conclusion Electrical stimulation of the tragus and concha auriculae can regulate the functioning of the cardiac vagus nerve, but stimulating the helix cannot. This is partly because the nerve signals in tragus or concha auriculae stimulation and the cardiac sensory nerve signal are integrated in the inferior ganglion and then analyzed and processed in the bulbar center to monitor the heart.