Objective:To develop a recombinant protein vaccine based on KPC-2, a drug resistance target in Klebsiella pneumoniae, and evaluate its immunogenicity, protective efficacy and mechanism in a mouse model of pneumonia. Methods:KPC-2 was expressed in Escherichia coli and purified using GST affinity chromatography. A recombinant protein vaccine was prepared with KPC-2 and used to immunize New Zealand rabbits through subcutaneous injection. Serum samples were isolated from cardiac blood and Protein G chromatography was used to purify polyclonal antibodies against KPC-2. Opsonophagocytic killing assay was used to assess the bactericidal activity of the polyclonal antibodies in vitro. Female BALB/c mice were immunized three times with the recombinant protein vaccine, and the titers of specific IgG antibodies in serum were measured by indirect ELISA. One week after the last vaccination, the mice were infected with Klebsiella pneumoniae strain SRT through tracheal intubation, and received a single intravenous dose of meropenem (0.1 mg) 1 h later. The protective efficacy of the KPC-2 recombinant protein vaccine was evaluated by comparing the survival rates, bacterial colonization and histopathological changes between vaccine group and adjuvant group as well as the survival rates between meropenem group and normal saline group. Moreover, the protective efficacy of polyclonal antibodies against KPC-2 was evaluated through passive immunization. Results:The level of specific IgG antibodies in serum was significantly higher in the vaccine group than in the adjuvant group ( t=4.325, P<0.05). The survival rate in the vaccine group was also higher than that of the adjuvant group [70% (7/10) vs 10% (1/10), P<0.05]. Furthermore, lung inflammation was less severe and bacterial burden was reduced in the vaccine group as compared with those of the control group ( t=3.127, P<0.05). Both active and passive vaccination strategies demonstrated strong protective efficacy against Klebsiella pneumoniae infection, and had a synergistic effect when used in combination with antibiotic therapy. The polyclonal antibodies against KPC-2 had bactericidal activity in vitro ( t=5.427, P<0.05). Conclusions:The prepared KPC-2 vaccine has better immunogenicity and protective efficacy. It can induce strong humoral immune responses. This study suggest that drug resistance target may be used as a candidate antigen for future vaccine development.

Objective This paper intends to compare the efficacy and safety of high-dose dual regimens containing Vonoprazan and proton pump inhibitor in patients infected with Helicobacter pylori(H.pylori).Methods A prospective randomized controlled study was conducted.According to inclusion and exclusion criteria.,243 patients with H.pylori infection admitted to the Department of Gastroenterology,the First Hospital of Lanzhou University from February 2023 to December 2023 were enrolled as the research objects.They were randomly divided into two groups.The high-dose dual therapy containing Vonoprazan group(VPZ-HDDT group)was given Vonoprazan fumarate tablet 20mg twice daily plus amoxicillin 750 mg four times daily for 14 days and the high-dose combination group containing PPI(PPI-HDDT group)was given esomeprazole 40 mg twice daily plus amoxicillin 750 mg four times daily for 14 days.Patients were followed up and recorded by telephone or WeChat on the 7th and 14th day of starting treatment for drug intake and occurrence of adverse reactions.Patients were instructed to recheck the 13C or 14C urea breath test at least 1 month after the end of medication.Treatment by protocol(PP)analysis,modified intention to treat(mITT)and intention-to-treat(ITT)analysis were used for H.pylori eradication rates in both groups,and compliance and incidence of adverse reactions were compared between the two groups.Results The eradication rates of the VPZ-HDDT group and the PPI-HDDT group in the initial treatment were 94.0％and 88.5％(P=0.209)by PP analysis,and 91.8％and 87.5％(P=0.358)86.7％by mITT analysis,and 81.9％(P=0.377)by ITT analysis,respectively.In the retreated patients,the PP analysis and mITT analysis eradication rates in these two groups were consistent,87.0％and 84.2％(P=0.800),respectively,and 83.3％and 76.2％(P=0.550)by ITT analysis.For the refractory H.pylori patients,the PP analysis and mITT analysis eradication rates in these two groups were also consistent,71.4％and 50.0％(P=0.429),and the eradication rates of ITT analysis were 62.5％and 50.0％(P=0.640),respectively.In different stratifications,the eradication rates of the VPZ-HDDT group were higher than those of the PPI-HDDT group,but the differences were not statistically significant.The incidence of adverse reactions and compliance of the VPZ-HDDT group and the PPI-HDDT group were similar,with no statistically significant differences.Conclusion Both two combination regimens can achieve clinically acceptable eradication rates(＞85％)in the first-time treatment patients.For the retreated and refractory patients,the choice of vonoprazan is more beneficial.

Linezolid,a fully synthetic oxazolidinone antibiotic,is mainly used to treat severe infections caused by Gram-positive drug-resistant bacteria.In recent years,with the rise in drug-resistant bacteria,the clinical utilization rate of linezolid and the incidence of linezolid-related adverse reactions in the hematological system and metabolic system have increased.The main adverse reactions include thrombocytopenia,anemia and lactic acidosis.Studies have shown that the causes of adverse reactions in linezolid-induced hematological system and metabolic system are diverse,and the mechanisms are not fully elucidated.In this review,the pharmacokinetic characteristics,mechanism of adverse reactions,risk factors,as well as preventive measures and individualized drug administration strategies of linezolid in vivo were discussed based on literature reports at home and abroad,aiming to provide references for clinical prevention and treatment of linezolid-related adverse reactions of hematological system and metabolic system.

Aim To study the regulation and mechanism of phloroglucinol in bladder smooth muscle spasm. Methods In vitro the experiment used bladder muscle strip to verify the relieving effect of phloro-glucinol on bladder spasm by different drugs. At the same time,RT-qPCR and Western blot were used to detect the expression levels of genes involved in the calcium signaling pathway caused by the antispasmodic effect of phloroglucinol. Results Phloroglucinol could relieve bladder spasm, and the antispasmodic effect was enhanced with the increase of concentration, and the expression of calponin 1 and MYLK3 in tissue cells increased. The results of RT-qPCR showed that the expression of Gprc5b G,Ppp2r5a, Chptl, Prkar2b ,Abcd2 and Rasdl genes in mouse bladder tissue significantly decreased, which was consistent with the sequencing results of RNA-seq.Conclusions Phloroglucinol can relieve bladder smooth muscle spasm, and its mechanism is related to calcium signaling pathway. Meanwhile, phloroglucinol also inhibits the expression of Rasdl gene, suggesting that it may be related to cell cycle , protein phosphorylation, choline metabolism, ATP synthesis and tumor-related pathways.

Atherosclerotic cardiovascular disease(ASCVD)frequently results in sudden death and poses a serious threat to public health worldwide.The drugs approved for the prevention and treatment of ASCVD are usually used in combination but are inefficient owing to their side effects and single therapeutic targets.Therefore,the use of natural products in developing drugs for the prevention and treatment of ASCVD has received great scholarly attention.Andrographolide(AG)is a diterpenoid lactone compound extracted from Andrographis paniculata.In addition to its use in conditions such as sore throat,AG can be used to prevent and treat ASCVD.It is different from drugs that are commonly used in the prevention and treatment of ASCVD and can not only treat obesity,diabetes,hyperlipidaemia and ASCVD but also inhibit the pathological process of atherosclerosis(AS)including lipid accumulation,inflammation,oxidative stress and cellular abnormalities by regulating various targets and pathways.However,the pharmaco-logical mechanisms of AG underlying the prevention and treatment of ASCVD have not been corrobo-rated,which may hinder its clinical development and application.Therefore,this review summarizes the physiological and pathological mechanisms underlying the development of ASCVD and the in vivo and in vitro pharmacological effects of AG on the relative risk factors of AS and ASCVD.The findings support the use of the old pharmacological compound('old bottle')as a novel drug('novel wine')for the pre-vention and treatment of ASCVD.Additionally,this review summarizes studies on the availability as well as pharmaceutical and pharmacokinetic properties of AG,aiming to provide more information regarding the clinical application and further research and development of AG.

Abstract: Due to the continued emergence of multiple variants of SARS-CoV-2, the ongoing pandemic has resulted in severe mortality over the past two years. After the Alpha, Beta, Gamma and Delta variants, the most recent new variant of concern (VOC) strain to emerge is Omicron (B.1.1.529), which evolved as a result of the accumulation of a large number of mutations. The Omicron variant, which has a much higher transmission rate than the Delta variant, soon replaced the Delta variant and others, is now the dominant variant worldwide. The emergence of Omicron poses new challenges for the prevention and control of COVID-19 and has raised a number of concerns worldwide. Recently, cases of Omicron infection have been reported in several parts of China, and therefore this paper provides a comprehensive analysis and summary of the epidemiology and immune escape mechanisms of the Omicron variant. We also suggest some therapeutic strategies against the Omicron variant, including rapid diagnosis, genome analysis of emerging variants, ramping up of vaccination drives and receiving booster doses, updating the available vaccines, designing of multivalent vaccines able to generate hybrid immunity, up-gradation of medical facilities and strict implementation of adequate prevention and control measures need to be given high priority to handle the on-going COVID-19 pandemic successfully.

Objective: To evaluate the immunogenicity of group A+C meningococcal polysaccharide conjugate vaccine in infants under 2 years old. Methods: From March 2017 to June 2018, 1 932 healthy infants in Biyang County, Henan Province, who were not vaccinated with meningococcal meningitis vaccine and whose axillary temperature was ≤37.0 ℃, were recruited as participants. The 3 months and 6-11 months old infants were allocated to the experiment group and the control group in a ratio of 1∶1. Infants aged 12-23 months were allocated to the 1-dose group, the 2-dose group and the control group in a ratio of 1∶1∶1, with 276 infants in each group. The infants in the experiment group were intramuscularly injected with freeze-dried group A+C meningococcal polysaccharide conjugate vaccine to be evaluated, and infants in the control group received intramuscular injection of commercially available freeze-dried group A+C meningococcal conjugate vaccine. The venous blood of infants was collected 30 days before the first dose and after the last dose of inoculation, and the antibody seroconversion of each group was determined and compared. Results: The completion rate of immunogenicity study was 95.2% (1 839/1 932). Before inoculation, there was no statistical difference in the geometric mean titer and positive rate of group A+C antibodies between the experiment group and the control group in 3 months and 6-11 months old infants (all P values >0.05). The geometric mean titers and positive rate of group A antibodies in the 1-dose group were higher than those in the control group (all P values <0.05), but there was no statistical difference between the 2-dose group and the control group (all P values >0.05) in infants aged 12-23 months. After inoculation, the differences (95%CI) in the positive conversion rate of group A+C antibodies between the experiment group and the control group were -0.12% (-6.01%-5.77%) and 0.82% (-4.23%-5.86%) in the 3 months old infants. At the age of 6-11 months, the differences were 6.75% (1.71%-11.79%) and -4.32% (-8.73%-0.08%), respectively. At the age of 12-23 months, the differences were 1.02% (-3.80%-5.83%) and -4.40% (-7.79%- -1.01%) in the 2-dose group and -7.22% (-12.90%- -1.54%) and -18.61% (-23.75%- -13.46%) in the 1-dose group, respectively. The geometric mean titers of group A+C antibodies in the 3 months old infants were 48.50 and 63.12, respectively, which had no significant difference from the control group (43.02 and 57.99, respectively) (both P values <0.05). The geometric mean titers of group A+C antibodies in the 6-11 months and 12-23 months old infants were 84.09 and 92.51 (2-dose group), which were higher than those in the corresponding control group (43.10 and 61.83, respectively) (all P values <0.001). Conclusion: Group A+C meningococcal conjugate vaccine has good immunogenicity in infants under 2 years old.
Humans ; Infant ; Child, Preschool ; Meningococcal Vaccines ; Vaccines, Conjugate ; Vaccination ; Neisseria meningitidis ; Polysaccharides ; Antibodies, Bacterial

Objective:To evaluate the skin development and repair process of X-ray radiation damage in rat with non-invasive two-photon excitation fluorescence (TPEF) imaging technology in vivo. Methods:Totally 24 SD rats were randomly divided into four groups including X-ray irradiated group (25, 35 and 45 Gy) and non-irradiation control group. At different times after irradiation, the degree of skin injury was evaluated, and the pathological changes of nicotinamide adenine dinucleotide (phosphate) [NAD(P)H] and collagen fiber fluorescence signals in epidermal cells were detected in vivo by TPEF imaging technology. Results:At 10 d post-irradiation, the skin of irradiation groups showed erythema and desquamation. At 15-20 d post-irradiation, the skin of radiation groups developed progressive exudation, edema and ulcers with increasing radiation dose. On day 25, the skin began to repair in the 25 Gy group, however, the skin of other groups still had exudation and ulcers. On day 10, NAD(P)H fluorescence signal in epidermal cells of irradiation groups decreased and the fluorescence signal of collagen fibers in papillary layer and reticular layer of irradiation groups reduced, which were significantly lower than that of normal control group ( t=24.145, 28.303, 26.989, 6.654, 7.510, 7.997, P<0.05). On day 30, fluorescence signal of NAD(P)H and collagen fibers in epidermal cells and dermis began to repair, the cell from stratum granulosum, stratum spinosum, and stratum basale in the 25 Gy group showed fluorescence signal, the other groups did not show. The fluorescence signal of collagen fibers in the 25 Gy group were gradually increased in papillary layer and reticular layer, however, they were significantly lower than normal control group ( t=115.133, 17.431, P<0.05), the skin of 45 Gy group did not show fluorescence signal of collagen fibers. Conclusions:The damage and repair process of epidermal cells and dermal collagen fiber can be detected noninvasively by TPEF imaging technology after X-ray irradiation in vivo.

The mammalian epididymis not only plays a fundamental role in the maturation of spermatozoa, but also provides protection against various stressors. The foremost among these is the threat posed by oxidative stress, which arises from an imbalance in reactive oxygen species and can elicit damage to cellular lipids, proteins, and nucleic acids. In mice, the risk of oxidative damage to spermatozoa is mitigated through the expression and secretion of glutathione peroxidase 5 (GPX5) as a major luminal scavenger in the proximal caput epididymidal segment. Accordingly, the loss of GPX5-mediated protection leads to impaired DNA integrity in the spermatozoa of aged Gpx5