Mercury (Hg)-contaminated soil poses a significant threat to the environment and human health. Hg-resistant microorganisms have the ability to survive under the stress of inorganic and organic Hg and effectively reduce Hg levels and toxicity. Compared to physical and chemical remediation methods, microbial remediation technologies have garnered increasing attention in recent years due to their lower cost, remarkable efficacy, and minimal environmental impact. This paper systematically elucidates the molecular mechanisms of Hg resistance in microbes, with a focus on their potential applications in phytoremediation of Hg-contaminated soils through plant-microbe interactions. Furthermore, it highlights the critical role of microbes in enhancing the effectiveness of transgenic plants for Hg remediation, aiming to provide a theoretical foundation and scientific basis for the bioremediation of Hg-contaminated soils.
Mercury/toxicity* ; Biodegradation, Environmental ; Soil Pollutants/isolation & purification* ; Soil Microbiology ; Plants, Genetically Modified/metabolism* ; Bacteria/genetics*

Objective: To investigate the current status and trends of depressive symptoms among middle school and college students in Hunan Province, and to explore the primary related factors of depressive symptoms, so as to provide a scientific basis for strengthening mental health among students. Methods: A total of 279 382 students in Hunan Province were selected through a stratified cluster random sampling method from 2021 to 2023. National Survey Questionnaire on Common Diseases and Health Influencing Factors among Students was adopted for the survey, and the Center for Epidemiological Studies Depression Scale was used to assess their depressive symptoms. The χ 2 test and trend χ 2 test were used to analyze depressive symptoms prevalence and trends, and multivariable Logistic regression was used to analyze the related factors of depressive symptoms. Results: The prevalence of depressive symptoms among students in Hunan Province from 2021 to 2023 were 19.66%, 20.17% and 21.47%, respectively, showing an upward trend ( χ 2 trend =9.07, P <0.01). In addition, the results of the multivariable Logistic regression analysis showed that students with healthy diet ( OR=0.43, 95%CI =0.40-0.45), adequate sleep ( OR=0.88, 95%CI =0.86-0.90), and acceptable screen time ( OR=0.61, 95%CI =0.60-0.62) had lower risks in depressive symptoms detection, while students with smoking ( OR= 1.95, 95%CI =1.88-2.02), secondhand smoke exposure ( OR=1.33, 95%CI =1.30-1.36) and Internet addiction ( OR= 4.19 , 95%CI =4.05-4.34) had higher risks in depressive symptoms detection, with differences in the degree of association among different genders, educational stages and urban rural groups ( OR=0.40-6.04, Z =-12.69-11.98) ( P <0.05). Conclusions There is an increasing trend of depressive symptoms among middle school and college students in Hunan Province from 2021 to 2023.Targeted depression prevention measures should be taken for students with different demographic characteristics to promote their mental health.

This paper reviews the current situation of massive open online course (MOOC) construction both domestically and internationally, highlighting the similarities, differences, and limitations of MOOC construction across nations. Based on the full-cycle MOOC construction of the "clinical epidemiology" course at Southern Medical University, including course design, resource integration, online deployment, and teaching evaluation, this study explored the significance, implementation path, and challenges of MOOC construction. This paper also reflects on the activation of teaching content, teacher-student interaction, and teaching mode, aiming to provide a reference for the construction and continuous enhancement of MOOC in China.

Objective:To evaluate the role of docosahexaenoic acid (DHA) in long-term cognitive impairment after multiple sevoflurane anesthesia in newborn mice.Methods:Clean-grade healthy male C57BL/6 mice, aged 6 days, were used in this study. Ten mice were divided into 2 groups ( n=5 each) by the random number table method: control group (group C) and sevoflurane group (group S). The animals inhaled 3% sevoflurane for 2 h at 6, 7 and 8 days after birth. The DHA content was detected by ultra-high performance liquid chromatography-mass spectrometry at 9 days of age. Fifty-two mice were selected and divided into 4 groups ( n=13 each) by a random number table method: control+ normal saline group (group C+ S), sevoflurane anesthesia + normal saline group (group S+ S), control+ DHA group (group C+ D), and sevoflurane anesthesia+ DHA group (group S+ D). The sevoflurane anesthesia method was the same as the one mentioned above. DHA 50 mg/kg was administered by intragastric gavage from postnatal days 6-19 (at 6, 7 and 8 days after birth, 2 h before anesthesia) in C+ D and S+ D groups. The equal volume of normal saline was given instead in C+ S group and S+ S group. The novel object recognition test was conducted at 37 days of age, and the Morris water maze test was performed at 42 days of age. The corpus callosum and hippocampal tissues were isolated at 47 days of age for examination of the ultrastructure of myelin (with a transmission electron microscope) and for determination of the expression of myelin basic protein (MBP) in hippocampal tissues (by Western blot). The G-ratio was calculated. Results:Compared with group C, the content of DHA in hippocampal tissues was significantly decreased in group S ( P<0.05). Compared with group C+ S, the discrimination index was significantly decreased, the percentage of duration of staying at the target platform quadrant and the number of crossing the original platform were decreased, the expression of MBP was down-regulated, and the G-ratio in the original platform and hippocampus was increased in S+ S group ( P<0.05). Compared with group S+ S, the discrimination index was significantly increased, the percentage of duration of staying at the target platform quadrant and the number of crossing the original platform were increased, the expression of MBP was up-regulated, and the G-ratio in the original platform and hippocampus was decreased in S+ D group ( P<0.05). Conclusions:The mechanism of long-term cognitive impairment following multiple sevoflurane anesthesia may be related to a decrease in the content of DHA, which subsequently leads to myelin structural damage in neonatal mice.

Objective:To evaluate the relationship between preoperative gut microbiota and post-operative ventilator-associated pneumonia (VAP) in patients undergoing coronary artery bypass grafting.Methods:This was a secondary analysis of a previous research project study. Patients who received invasive mechanical ventilation treatment after elective off-pump coronary artery bypass grafting at the Second Hospital of Hebei Medical University from April to September 2023 were selected and divided into VAP group and non-VAP group based on whether VAP occurred after surgery. Fecal samples were collected from patients before surgery, and 16S rRNA gene sequencing was used to analyze the characteristics of preoperative gut microbiota in the two groups. The differences in the diversity of gut microbiota between the two groups were compared. The linear discriminant analysis was used to identify the gut microbiota with significant differences between groups (differential bacteria), and logistic regression analysis was conducted to assess the association between differential bacteria and VAP. Receiver operating characteristic curves were drawn to analyze the predictive value of the differential bacteria for VAP.Results:A total of 79 patients were finally included, with 25 in VAP group and 54 in non-VAP group. The Beta diversity analysis showed statistically significant differences between VAP group and non-VAP group (pseudo- F=2.00, P=0.002). The linear discriminant analysis indicated that Bifidobacterium, Blautia and Megamonas were enriched in non-VAP group, while Klebsiella was enriched in VAP group. Multivariate logistic regression analysis showed that the relative abundance of Bifidobacterium was a protective factor for postoperative VAP ( OR=0.32, 95% confidence interval [ CI] 0.15-0.71, P=0.005), and the relative abundance of Klebsiella was a risk factor for postoperative VAP ( OR=2.49, 95% CI 1.143-5.43, P=0.022). The area under the receiver operating characteristic curve of the relative abundance of Bifidobacterium for predicting VAP was 0.80 (95% CI 0.69-0.90, P<0.001) and of the relative abundance of Klebsiella was 0.70 (95% CI 0.57-0.83, P=0.005). Conclusions:Bifidobacterium is a protective factor, while Klebsiella is a risk factor for postoperative VAP in patients undergoing coronary artery bypass grafting, and the relative abundance of both bacteria has a certain predictive value for VAP.

This paper reviews the current situation of massive open online course (MOOC) construction both domestically and internationally, highlighting the similarities, differences, and limitations of MOOC construction across nations. Based on the full-cycle MOOC construction of the "clinical epidemiology" course at Southern Medical University, including course design, resource integration, online deployment, and teaching evaluation, this study explored the significance, implementation path, and challenges of MOOC construction. This paper also reflects on the activation of teaching content, teacher-student interaction, and teaching mode, aiming to provide a reference for the construction and continuous enhancement of MOOC in China.

Objective:To evaluate the role of docosahexaenoic acid (DHA) in long-term cognitive impairment after multiple sevoflurane anesthesia in newborn mice.Methods:Clean-grade healthy male C57BL/6 mice, aged 6 days, were used in this study. Ten mice were divided into 2 groups ( n=5 each) by the random number table method: control group (group C) and sevoflurane group (group S). The animals inhaled 3% sevoflurane for 2 h at 6, 7 and 8 days after birth. The DHA content was detected by ultra-high performance liquid chromatography-mass spectrometry at 9 days of age. Fifty-two mice were selected and divided into 4 groups ( n=13 each) by a random number table method: control+ normal saline group (group C+ S), sevoflurane anesthesia + normal saline group (group S+ S), control+ DHA group (group C+ D), and sevoflurane anesthesia+ DHA group (group S+ D). The sevoflurane anesthesia method was the same as the one mentioned above. DHA 50 mg/kg was administered by intragastric gavage from postnatal days 6-19 (at 6, 7 and 8 days after birth, 2 h before anesthesia) in C+ D and S+ D groups. The equal volume of normal saline was given instead in C+ S group and S+ S group. The novel object recognition test was conducted at 37 days of age, and the Morris water maze test was performed at 42 days of age. The corpus callosum and hippocampal tissues were isolated at 47 days of age for examination of the ultrastructure of myelin (with a transmission electron microscope) and for determination of the expression of myelin basic protein (MBP) in hippocampal tissues (by Western blot). The G-ratio was calculated. Results:Compared with group C, the content of DHA in hippocampal tissues was significantly decreased in group S ( P<0.05). Compared with group C+ S, the discrimination index was significantly decreased, the percentage of duration of staying at the target platform quadrant and the number of crossing the original platform were decreased, the expression of MBP was down-regulated, and the G-ratio in the original platform and hippocampus was increased in S+ S group ( P<0.05). Compared with group S+ S, the discrimination index was significantly increased, the percentage of duration of staying at the target platform quadrant and the number of crossing the original platform were increased, the expression of MBP was up-regulated, and the G-ratio in the original platform and hippocampus was decreased in S+ D group ( P<0.05). Conclusions:The mechanism of long-term cognitive impairment following multiple sevoflurane anesthesia may be related to a decrease in the content of DHA, which subsequently leads to myelin structural damage in neonatal mice.

Objective:To evaluate the relationship between preoperative gut microbiota and post-operative ventilator-associated pneumonia (VAP) in patients undergoing coronary artery bypass grafting.Methods:This was a secondary analysis of a previous research project study. Patients who received invasive mechanical ventilation treatment after elective off-pump coronary artery bypass grafting at the Second Hospital of Hebei Medical University from April to September 2023 were selected and divided into VAP group and non-VAP group based on whether VAP occurred after surgery. Fecal samples were collected from patients before surgery, and 16S rRNA gene sequencing was used to analyze the characteristics of preoperative gut microbiota in the two groups. The differences in the diversity of gut microbiota between the two groups were compared. The linear discriminant analysis was used to identify the gut microbiota with significant differences between groups (differential bacteria), and logistic regression analysis was conducted to assess the association between differential bacteria and VAP. Receiver operating characteristic curves were drawn to analyze the predictive value of the differential bacteria for VAP.Results:A total of 79 patients were finally included, with 25 in VAP group and 54 in non-VAP group. The Beta diversity analysis showed statistically significant differences between VAP group and non-VAP group (pseudo- F=2.00, P=0.002). The linear discriminant analysis indicated that Bifidobacterium, Blautia and Megamonas were enriched in non-VAP group, while Klebsiella was enriched in VAP group. Multivariate logistic regression analysis showed that the relative abundance of Bifidobacterium was a protective factor for postoperative VAP ( OR=0.32, 95% confidence interval [ CI] 0.15-0.71, P=0.005), and the relative abundance of Klebsiella was a risk factor for postoperative VAP ( OR=2.49, 95% CI 1.143-5.43, P=0.022). The area under the receiver operating characteristic curve of the relative abundance of Bifidobacterium for predicting VAP was 0.80 (95% CI 0.69-0.90, P<0.001) and of the relative abundance of Klebsiella was 0.70 (95% CI 0.57-0.83, P=0.005). Conclusions:Bifidobacterium is a protective factor, while Klebsiella is a risk factor for postoperative VAP in patients undergoing coronary artery bypass grafting, and the relative abundance of both bacteria has a certain predictive value for VAP.

OBJECTIVE: To investigate the molecular mechanisms underlying the beneficial effect of electroacupuncture (EA) in experimental models of Alzheimer's disease (AD) in vivo. METHODS: Senescence-accelerated mouse prone 8 (SAMP8) mice were used as AD models and received EA at Yingxiang (LI 20, bilateral) and Yintang (GV 29) points for 20 days. For certain experiments, SAMP8 mice were injected intravenously with human fibrin (2 mg). The Morris water maze test was used to assess cognitive and memory abilities. The changes of tight junctions of blood-brain barrier (BBB) in mice were observed by transmission electron microscope. The expressions of fibrin, amyloid- β (Aβ), and ionized calcium-binding adapter molecule 1 (IBa-1) in mouse hippocampus (CA1/CA3) were detected by reverse transcription-quantitative polymerase chain reaction (qRT-PCR), Western blot or immunohistochemical staining. The expression of fibrin in mouse plasma was detected by enzyme-linked immunosorbent assay. The expressions of tight junction proteins zonula occludens-1 and claudin-5 in hippocampus were detected by qRT-PCR and immunofluorescence staining. Apoptosis of hippocampal neurons was detected by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) staining. RESULTS: Fibrin was time-dependently deposited in the hippocampus of SAMP8 mice and this was inhibited by EA treatment (P<0.05 or P<0.01). Furthermore, EA treatment suppressed the accumulation of Aβ in the hippocampus of SAMP8 mice (P<0.01), which was reversed by fibrin injection (P<0.05 or P<0.01). EA improved SAMP8 mice cognitive impairment and BBB permeability (P<0.05 or P<0.01). Moreover, EA decreased reactive oxygen species levels and neuroinflammation in the hippocampus of SAMP8 mice, which was reversed by fibrin injection (P<0.05 or P<0.01). Mechanistically, EA inhibited the promoting effect of fibrin on the high mobility group box protein 1 (HMGB1)/toll-like receptor 4 (TLR4) and receptor for advanced glycation end products (RAGE)/nicotinamide adenine dinucleotide phosphate (NADPH) signaling pathways (P<0.01). CONCLUSION EA may potentially improve cognitive impairment in AD via inhibition of fibrin/A β deposition and deactivation of the HMGB1/TLR4 and RAGE/NADPH signaling pathways.
Mice ; Humans ; Animals ; NADP/metabolism* ; Toll-Like Receptor 4 ; HMGB1 Protein/metabolism* ; Receptor for Advanced Glycation End Products/metabolism* ; Blood-Brain Barrier/metabolism* ; Neuroinflammatory Diseases ; Electroacupuncture ; Alzheimer Disease/therapy* ; Hippocampus/metabolism* ; Amyloid beta-Peptides/metabolism*