Objective To investigate the effect of dorsal repulsive axon guidance protein(Draxin)on the migration of trunk neural crest cells during the early development of embryonic mouse spinal cord.Methods Immunohistochemistry and in situ hybridization were used to detect the expression characteristics of Draxin in early embryonic spinal cord(8 mice each group);In situ hybridization was used to detect the change of migration characteristics of trunk neural crest cells in early embryonic spinal cord of different types of mouse(5 mice each group);in vitro culture method was used to check the effect of Draxin on the migration characteristics of embryonic mouse trunk neural crest cells(16 mice each group).Resultsβ-galactosidase gene Z(LacZ)gene was introduced when Draxin gene was knocked out to produce Draxin gene knockout mice.β-galactosidase staining was used to detect LacZ gene expression in Draxin knockout embryonic mice,and the result showed that Draxin expression was observed in the spinal cord of early embryonic mice since 9.5 days(E9.5).Draxin expression was obvious in the embryonic mice spinal cord in E10.5 period.In situ hybridization was used to detect the expression of Draxin gene in the spinal cord of wild type embryonic mice,and the result further verified the obvious expression of Draxin in the early embryonic mice spinal cord in El0.5 period.Sox10 in situ hybridization was used to detect neural crest cell migration in the spinal cord of embryonic mice in E10.5 period.The result showed that segmental migration of neural crest cells in the early embryonic spinal cord of some Draxin knockout mice was delayed compared with the wild type mice.The effect of Draxin on the migration of wild type early embryonic mice trunk neural crest cells in vitro was tested.The result showed that Draxin reduced the migration distance of neural crest cells in vitro.Conclusion In the early developmental stage of embryonic spinal cord(E9.5-E10.5),neural crest cells migrated exuberant.At the same time,Draxin plays an important inhibitory function in the formation of the specific migration pathways of trunk neural crest cells by promoting neural crest cells migrating away from Draxin expressing regions.

Objective:To analyze the short-term hospital-based transmission characteristics and gene variation of Carbapenem-Resistant Klebsiella pneumoniae (CRKP) by genome-wide technique to provide evidence for transmission control. Methods:The experimental strain was derived from all the CRKP isolated in Affiliated Hospital of North China University of Science and Technology from October 2022 to December 2023. Strain identification and drug susceptibility were tested with VITEK 2-Compact automatic bacterial identification drug susceptibility analyzer or disk method, and the results were interpreted through whole genome sequencing. The ST type, carbapenem resistance gene, virulence factor, and O serotype of the collected strains were analyzed.Results:Among the 115 strains of CRKP, 94 strains were isolated from the intensive care unit (ICU), accounting for 81.7%, and 21 strains were isolated from the non-intensive care unit (NICU), accounting for 18.3%. The 115 strains of CRKP can be divided into 11 ST types, of which ST11 type was the most (54.8%, 63/115), followed by ST15 type (22.6%, 26/115) and ST5492 type (15.7%, 18/115). Type ST5492 was a new clonal group in the region. The 115 strains of CRKP could be divided into 7 O serotypes, most of which were O2a type(32.2%,37/115), followed by O5 type(30.4%,35/115) and O1 type(27.8%,32/115). The resistance genes of carbapenem antibiotics showed that there were 107 strains carrying the blaKPC-2 gene, one strain with the blaNDM-1 gene, and one strain with both the blaKPC-2 and blaNDM-13 genes. Virulence genes were detected in 55 CRKP strains (47.8%, 55/115), among which six strains detected peg-344, iucA, iroB, rmpA, and rmpA2 virulence genes (5.2%, 6/115). Four virulence genes ( peg-344, iucA, rmpA, and rmpA2) were detected in 34 strains (29.6%, 34/115). Three virulence genes ( iucA, iroB and rmpA) were detected in two strains (1.7%, 2/115). Three virulence genes ( peg-344, iucA and rmpA) were detected in one strain (0.8%, 1/115). IucA and rmpA virulence genes were detected in 12 strains (10.4%, 12/115). KPC-2_ST11_O2a, KPC-2_ST15_O1 and KPC-2_ST5492_O5 were dominant clones, and their distribution was mainly in the intensive care unit. The whole genome sequence analysis showed that there were three dominant clones, among which ST11 clones were subdivided into three dominant O serotypes, all of which were mainly in the intensive care unit. Conclusion:The popular strain in the hospital of CRKP is a KPC-2_ST11 clone group carrying iucA, rmpA/rmpA2, with cross-department transmission and mutation. ST5492 is a newly-launched clone type. The intensive care unit of hvKP carrying five virulence genes, including peg-344, should be alert to the epidemic risk of CR-hvKP outbreak.

Objective:Invasive pulmonary mucormycosis(PM)is a rare but highly lethal opportunistic infection.COVID-19 associated mucormycosis(CAM)is difficult to diagnose,often leading to misdiagnosis or missed diagnosis,and has poor treatment outcomes.This study reports a case of successfully treated CAM and explores optimized diagnostic and therapeutic strategies.Methods:A retrospective analysis of the diagnosis and treatment process in a 50-year-old female patient with COVID-19 associated with diabetic ketoacidosis(DKA)and invasive pulmonary mucormycosis was conducted.Combined with a literature review,the therapeutic efficacy of local bronchoscopic instillation in conjunction with systemic treatment using liposomal Amphotericin B(L-AmB)was specifically evaluated.Results:The patient was rapidly diagnosed with Rhizopus microsporus infection through metagenomic next-generation sequencing(mNGS).She subsequently received antifungal treatment with intravenous L-AmB combined with local bronchoscopic instillation.After treatment,the patient was significantly improved,with imaging studies showing gradual absorption of the lesions.Follow-up at six months revealed no recurrence.A literature review suggests that early diagnosis and multimodal therapy are key to improving survival rates in patients with CAM.Conclusion:mNGS can significantly improve the early diagnosis rate of CAM.The combination of local and systemic treatment with L-AmB is valuable in improving prognosis.Early diagnosis,multimodal antifungal therapy,and individualized management are key to increasing the survival rate of patients with CAM.

To investigate the effects of phosphorus fertilizer on the morphological traits, active ingredients and rhizosphere soil microbial community of Polygala tenuifolia. The phosphorus fertilizer was calculated in terms of P_2O_5. Five treatments were set up: 0(CK), 17(P1), 34(P2), 51(P3), and 68(P4) kg per Mu(1 Mu≈667 m~2). A randomized block design was adopted. Samples of P. tenuifolia and its rhizosphere soil were collected under different superphosphate fertilizer treatments. Illumina high-throughput sequencing was used to analyze the rhizosphere soil microbial community, 9 morphological traits were measured and the content of 11 active ingredients were determined. The results showed that the whole plant weight, shoot fresh weight, root weight, and root peel thickness were the highest under P1 treatment, increasing by 34.41%, 38.80%, 39.21%, and 3.17% respectively compared to CK. Under P2 treatment, the plant height, stem diameter, root thickness, and core thickness were significantly higher than CK. Phosphorus fertilizer had a significant impact on the content of tenuifolin, sibiricose A5, sibiricose A6, arillanin A, 3,6'-disinapoyl sucrose, and polygalaxanthone Ⅲ. Correlation analysis results showed that the relative abundance of Arthrobacter, Bacillus, norank＿f＿Vicinamibacteraceae, norank＿o＿Vicinamibacterales, MND1 and other bacteria, as well as the relative abundance of Neocosmospora, Paraphoma and other fungi were positively correlated with root diameter, wood core diameter, the whole plant weight, root weight, shoot fresh weight of P. tenuifolia. Bacillus, Neocosmospora, Subulicystidium were significantly positively correlated with oligosaccharides such as 3,6'-disinapoyl sucrose, sibiricose A5、sibiricose A6、glomeratose A、arillanin A and tenuifoliside C. Arthrobacter, Humicola, Aspergillus, Paraphoma were positively correlated with tenuifolin and norank＿f＿Vicinamibacteraceae, norank＿o＿Vicinamibacterales, Fusarium were positively correlated with polygalaxanthone Ⅲ. Evidently, appropriate phosphorus application is conducive to the growth and quality improvement of P. tenuifolia, and can increase the abundance of beneficial microorganisms in the soil.
Rhizosphere ; Phosphorus/pharmacology* ; Soil Microbiology ; Polygala/anatomy & histology* ; Fertilizers/analysis* ; Bacteria/metabolism* ; Soil/chemistry* ; Microbiota/drug effects* ; Plant Roots/metabolism*

Objective:Invasive pulmonary mucormycosis(PM)is a rare but highly lethal opportunistic infection.COVID-19 associated mucormycosis(CAM)is difficult to diagnose,often leading to misdiagnosis or missed diagnosis,and has poor treatment outcomes.This study reports a case of successfully treated CAM and explores optimized diagnostic and therapeutic strategies.Methods:A retrospective analysis of the diagnosis and treatment process in a 50-year-old female patient with COVID-19 associated with diabetic ketoacidosis(DKA)and invasive pulmonary mucormycosis was conducted.Combined with a literature review,the therapeutic efficacy of local bronchoscopic instillation in conjunction with systemic treatment using liposomal Amphotericin B(L-AmB)was specifically evaluated.Results:The patient was rapidly diagnosed with Rhizopus microsporus infection through metagenomic next-generation sequencing(mNGS).She subsequently received antifungal treatment with intravenous L-AmB combined with local bronchoscopic instillation.After treatment,the patient was significantly improved,with imaging studies showing gradual absorption of the lesions.Follow-up at six months revealed no recurrence.A literature review suggests that early diagnosis and multimodal therapy are key to improving survival rates in patients with CAM.Conclusion:mNGS can significantly improve the early diagnosis rate of CAM.The combination of local and systemic treatment with L-AmB is valuable in improving prognosis.Early diagnosis,multimodal antifungal therapy,and individualized management are key to increasing the survival rate of patients with CAM.

Objective:To analyze the short-term hospital-based transmission characteristics and gene variation of Carbapenem-Resistant Klebsiella pneumoniae (CRKP) by genome-wide technique to provide evidence for transmission control. Methods:The experimental strain was derived from all the CRKP isolated in Affiliated Hospital of North China University of Science and Technology from October 2022 to December 2023. Strain identification and drug susceptibility were tested with VITEK 2-Compact automatic bacterial identification drug susceptibility analyzer or disk method, and the results were interpreted through whole genome sequencing. The ST type, carbapenem resistance gene, virulence factor, and O serotype of the collected strains were analyzed.Results:Among the 115 strains of CRKP, 94 strains were isolated from the intensive care unit (ICU), accounting for 81.7%, and 21 strains were isolated from the non-intensive care unit (NICU), accounting for 18.3%. The 115 strains of CRKP can be divided into 11 ST types, of which ST11 type was the most (54.8%, 63/115), followed by ST15 type (22.6%, 26/115) and ST5492 type (15.7%, 18/115). Type ST5492 was a new clonal group in the region. The 115 strains of CRKP could be divided into 7 O serotypes, most of which were O2a type(32.2%,37/115), followed by O5 type(30.4%,35/115) and O1 type(27.8%,32/115). The resistance genes of carbapenem antibiotics showed that there were 107 strains carrying the blaKPC-2 gene, one strain with the blaNDM-1 gene, and one strain with both the blaKPC-2 and blaNDM-13 genes. Virulence genes were detected in 55 CRKP strains (47.8%, 55/115), among which six strains detected peg-344, iucA, iroB, rmpA, and rmpA2 virulence genes (5.2%, 6/115). Four virulence genes ( peg-344, iucA, rmpA, and rmpA2) were detected in 34 strains (29.6%, 34/115). Three virulence genes ( iucA, iroB and rmpA) were detected in two strains (1.7%, 2/115). Three virulence genes ( peg-344, iucA and rmpA) were detected in one strain (0.8%, 1/115). IucA and rmpA virulence genes were detected in 12 strains (10.4%, 12/115). KPC-2_ST11_O2a, KPC-2_ST15_O1 and KPC-2_ST5492_O5 were dominant clones, and their distribution was mainly in the intensive care unit. The whole genome sequence analysis showed that there were three dominant clones, among which ST11 clones were subdivided into three dominant O serotypes, all of which were mainly in the intensive care unit. Conclusion:The popular strain in the hospital of CRKP is a KPC-2_ST11 clone group carrying iucA, rmpA/rmpA2, with cross-department transmission and mutation. ST5492 is a newly-launched clone type. The intensive care unit of hvKP carrying five virulence genes, including peg-344, should be alert to the epidemic risk of CR-hvKP outbreak.

ObjectiveTo investigate the effects of maltol aluminum exposure on miR-193a-3p, demethylase AlkB homolog 5 (ALKBH5), phosphatase and tensin homolog deleted on chromosome ten (PTEN) and protein kinase B (AKT), and whether miR-193a-3p is involved in aluminum-induced cognitive impairment by regulating ALKBH5/PTEN/AKT signaling pathway. Methods Specific pathogen-free male SD rats were randomly divided into control group and low-, medium- and high- dose groups according to their body weight, with eight rats in each group. Rats in the low-, medium-, and high- dose groups were intraperitoneally injected with maltol aluminum solution at concentrations of 10.00, 20.00, and 40.00 μmol/kg body weight, respectively, while the rats in control group were given an equal volume of 0.9% sodium chloride solution. Rats were injected for five days every week for three months. After injection, the novel object recognized test was used to assess the learning and memory ability of the rats. The relative expression of miR-193a-3p and B-cell lymphocytoma-2 (Bcl-2), Bcl-2 associated X protein (Bax) and cysteine aspartate protease-3 (Caspase-3) mRNA in rat hippocampus was detected using the real-time quantitative polymerase chain reaction. The relative protein expression of ALKBH5, PTEN, and AKT2 in the rat hippocampus was detected using Western blot. Results The discrimination index and the preference index of the new object recognition test of the rats in high-dose group were lower than those in control group and low-dose group (all P<0.05). The relative expression of miR-193a-3p and Bcl-2 mRNA in the hippocampus of the rats in high-dose group was lower than those in control group and low-dose group (all P<0.05). The relative mRNA expression of Bax in the high-dose group was higher than those in the control group and low-dose group (both P<0.05). The relative mRNA expression of Caspase-3 of the rats in the high-dose group was higher than that in the other three groups (both P<0.05). The relative protein expression of ALKBH5 in the hippocampus of the rats in the high-dose group was lower than that in the control group (P<0.05). The relative expression of PTEN protein was higher than those in the control group and low-dose group (both P<0.05). The relative protein expression of AKT2 was lower than those in the control group and low-dose group (both P<0.05). Conclusion Sub-chronic aluminum exposure can inhibit the expression of miR-193a-3p in the hippocampus of rats, which may disrupt the ALKBH5/PTEN/AKT pathway and affect normal neuronal homeostasis and cellular function. This pathway may play an important role in aluminum-induced cognitive impairment.

Objective:To analyze the drug resistance characteristics of Klebsiella pneumoniae in the nasopharynx of hospitalized patients in North China from 2022 to 2023. Methods:From November 2022 to July 2023, nasopharyngeal swabs were collected from 100 inpatients in Affiliated Hospital of North China University of Science and Technology, and Klebsiella pneumoniae was isolated and cultured. At the same time, the clinical data of the patients were collected, including gender, age, department, clinical diagnosis of disease type, etc. The minimum inhibitory concentration of strains was detected by an automatic bacterial drug sensitivity system. The drug resistance genes, ST types, capsule serotypes and population structure of the strains were analyzed by whole genome sequencing and data analysis. Results:Klebsiella pneumoniae was isolated from 55 nasopharyngeal swabs of 100 inpatients(55.00%). Among the 55 inpatients with Klebsiella pneumoniae in the nasopharynx, 70.91% (39/55) were male, with an age distribution concentrated between 61 and 80 years old (58.18%, 32/55), and 50.91% (28/55) were in intensive care units (ICU). The main underlying disease type was nervous system disease (49.09%, 27/55). The results of drug sensitivity showed that the non-susceptibility rates of 55 strains of Klebsiella pneumoniae to cephalosporins, quinolones, aztreonam and nitrofurantoin were all more than 80.00%. Twenty-eight carbapenem-resistant Klebsiella pneumoniae strains (50.91%), 47 extended-spectrum β-lactamase producing strains (85.45%), and 48 multi-drug-resistant strains (87.27%) were detected. A total of 11 antibiotic resistance genes were detected, including carbapenems (carrying rate 76.36%) and extended-spectrum β-lactamase (carrying rate 96.36%). The 55 strains could be divided into 17 ST types, and the most common type was ST11 (25.45%). The 55 strains were divided into 18 capsular serotypes, among which K102 was the most prevalent (23.64%). OXA-1_ST307_K102 (21.82%) and KPC-2_ST5492_K125 (18.18%) were the dominant clones, distributed in the Department of Neurosurgery and ICU. The result of whole genome sequence analysis showed that there were four clusters with high homology among the 55 strains. The strains from the ICU formed two independent clusters, and strains from the Neurology ICU and Neurosurgery department formed one cluster respectively. Conclusion:The carrying rate of Klebsiella pneumoniae in the nasopharynx of inpatients is high, and the drug resistance of the strains is serious. There are many types of drug-resistant genes.

Objective:To analyze the drug resistance characteristics of Klebsiella pneumoniae in the nasopharynx of hospitalized patients in North China from 2022 to 2023. Methods:From November 2022 to July 2023, nasopharyngeal swabs were collected from 100 inpatients in Affiliated Hospital of North China University of Science and Technology, and Klebsiella pneumoniae was isolated and cultured. At the same time, the clinical data of the patients were collected, including gender, age, department, clinical diagnosis of disease type, etc. The minimum inhibitory concentration of strains was detected by an automatic bacterial drug sensitivity system. The drug resistance genes, ST types, capsule serotypes and population structure of the strains were analyzed by whole genome sequencing and data analysis. Results:Klebsiella pneumoniae was isolated from 55 nasopharyngeal swabs of 100 inpatients(55.00%). Among the 55 inpatients with Klebsiella pneumoniae in the nasopharynx, 70.91% (39/55) were male, with an age distribution concentrated between 61 and 80 years old (58.18%, 32/55), and 50.91% (28/55) were in intensive care units (ICU). The main underlying disease type was nervous system disease (49.09%, 27/55). The results of drug sensitivity showed that the non-susceptibility rates of 55 strains of Klebsiella pneumoniae to cephalosporins, quinolones, aztreonam and nitrofurantoin were all more than 80.00%. Twenty-eight carbapenem-resistant Klebsiella pneumoniae strains (50.91%), 47 extended-spectrum β-lactamase producing strains (85.45%), and 48 multi-drug-resistant strains (87.27%) were detected. A total of 11 antibiotic resistance genes were detected, including carbapenems (carrying rate 76.36%) and extended-spectrum β-lactamase (carrying rate 96.36%). The 55 strains could be divided into 17 ST types, and the most common type was ST11 (25.45%). The 55 strains were divided into 18 capsular serotypes, among which K102 was the most prevalent (23.64%). OXA-1_ST307_K102 (21.82%) and KPC-2_ST5492_K125 (18.18%) were the dominant clones, distributed in the Department of Neurosurgery and ICU. The result of whole genome sequence analysis showed that there were four clusters with high homology among the 55 strains. The strains from the ICU formed two independent clusters, and strains from the Neurology ICU and Neurosurgery department formed one cluster respectively. Conclusion:The carrying rate of Klebsiella pneumoniae in the nasopharynx of inpatients is high, and the drug resistance of the strains is serious. There are many types of drug-resistant genes.

Objective To examine the antiplatelet effect of ticagrelor by microfluidic chip and flow cytometry under shear stress in vitro. Methods Microfluidic chip was used to examine the effect of ticagrelor on platelet aggregation at the shear rates of 300/s and 1500/s.We adopted the surface coverage of platelet aggregation to calculate the half inhibition rate of ticagrelor.The inhibitory effect of ticagrelor on ADP-induced platelet aggregation was verified by optical turbidimetry.Microfluidic chip was used to construct an in vitro vascular stenosis model,with which the platelet reactivity under high shear rate was determined.Furthermore,the effect of ticagrelor on the expression of fibrinogen receptor (PAC-1) and P-selectin (CD62P) on platelet membrane activated by high shear rate was analyzed by flow cytometry. Results At the shear rates of 300/s and 1500/s,ticagrelor inhibited platelet aggregation in a concentration-dependent manner,and the inhibition at 300/s was stronger than that at 1500/s (both P<0.001).Ticagrelor at a concentration ≥4 μmol/L almost completely inhibited platelet aggregation.The inhibition of ADP-induced platelet aggregation by ticagrelor was similar to the results under flow conditions and also in a concentration-dependent manner.Ticagrelor inhibited the expression of PAC-1 and CD62P. Conclusion We employed microfluidic chip to analyze platelet aggregation and flow cytometry to detect platelet activation,which can reveal the responses of different patients to ticagrelor.
Humans ; Ticagrelor/pharmacology* ; Platelet Aggregation Inhibitors/pharmacology* ; Flow Cytometry/methods* ; Microfluidics ; Platelet Aggregation