Pseudomonas aeruginosa(PA)is an opportunistic pathogen commonly involved in environmental-and difffcult-to-treat nosocomial infection.Currently,multidrug-resistant(MDR)and extensively drug-resistant(XDR)strains of PA are e-merging due to the inappropriate use of antibiotics,which has become a major threat related to healthcare.The antibiotics re-sistance mechanism of PA is very complicated.PA can acquire resistance through mutations in genes encoding for membrane-associated proteins,antibiotics inactivation enzymes and their regulatory proteins,antibiotics target proteins,and two-compo-nent systems.Additionally,resistance genes acquired by horizontal gene transfer(HGT)lead to resistance of PA,which are frequently localized within mobile genetic elements(MGEs),including genes encoding enzymes that inactivate and modify anti-biotics,proteins genes that protect and modify antibiotic targets.In this review,acquired resistance mechanisms of PA involved in gene mutations and HGT was summarized.This review would provide references for the prevention and treatment of PA in-fection,as well as the research and development of new antibiotics.

Objective:To compare the clinical efficacy of robot-assisted balloon tibioplasty and traditional open reduction and internal fixation in the treatment of AO/OTA type 41B2 tibial plateau fracture.Methods:A retrospective cohort study was conducted to analyze the clinical data of 70 patients with AO/OTA type 41B2 tibial plateau fracture who were admitted to Wuhan Fourth Hospital from September 2019 to October 2022, including 35 males and 35 females, aged 24-62 years [(44.9±9.5)years]. Among them, 41 patients underwent traditional open reduction and internal fixation (open reduction group), while 29 patients underwent robot-assisted balloon tibioplasty (balloon group). The following parameters were compared between the two groups: incision length, operative blood loss, number of intraoperative fluoroscopies, operation duration, and length of hospital stay; Rasmussen radiological scores at 3 days, 3 months postoperatively, and at the last follow-up and the fracture healing time; pain visual analogue scale (VAS) scores preoperatively, and at 2 days and 3 months postoperatively; knee joint range of motion at 5 days, 3 months postoperatively, and at the last follow-up; Hospital for Special Surgery (HSS) knee function scores at 3, 6 months postoperatively, and at the last follow-up; incidence rate of complications at 15 days postoperatively.Results:All the patients were followed for 12-24 months [18(17, 20)months]. The incision length, operative blood loss and length of hospital stay in the balloon group were 1.6(1.5, 3.0)cm, 5.0(5.0, 5.0)ml and 11.0(9.0, 14.0)days, less than those in the open reduction group [12.0(11.0, 12.0)cm, 100.0(50.0, 120.0)ml and 15.0(13.0, 20.0)days] ( P<0.01). The number of intraoperative fluoroscopies and operation duration in the open reduction group were 9.0(7.0, 10.0)times and 75.0(60.0, 90.0)minutes, less than those in the balloon group [336.0(335.0, 340.0)times and [90.0(70.0, 105.0)minutes] ( P<0.05). There were no significant differences in the Rasmussen radiological scores between the two groups at 3 days, 3 months postoperatively, or at the last follow-up ( P>0.05). The fracture healing time in the balloon group was 3.0(3.0, 3.0)months, shorter than 3.0(3.0, 3.5)months in the open reduction group ( P<0.05). No significant differences were observed between the two groups in VAS scores before operation or at 3 months postoperatively ( P>0.05). However, the VAS score was 2.0(2.0, 3.0)points at 2 days postoperatively in the balloon group, lower than 5.0(5.0, 6.0)points in the open reduction group ( P<0.01). The knee joint range of motion at 5 days, 3 months postoperatively and at the last follow-up were 90.0(85.0, 90.0)°, 135.0(130.0, 135.0)° and 140.0(135.0, 140.0)° in the balloon group, better than 65.0(60.0, 70.0)°, 125.0(120.0, 130.0)°, 130.0(130.0, 140.0)° in the open reduction group ( P<0.01). Similarly, the HSS knee function scores at 3, 6 months postoperatively and at the last follow-up were 80.0(80.0, 81.0)points, 91.0(90.0, 92.0)points, and 95.0(93.0, 96.0)points in the balloon group, better than 71.0(70.0, 72.0)points, 83.0(81.0, 84.0)points, and 86.0(84.0, 88.0)points in the open reduction group ( P<0.01). The incidence rate of complications in the balloon group was 0, comparable to 12% (5/41) in the open reduction group ( P>0.05). Conclusion:Compared with traditional open reduction and internal fixation surgery, robot-assisted balloon tibioplasty in the treatment of AO/OTA type 41B2 tibial plateau fracture significantly reduces surgical trauma, alleviates postoperative pain, promotes fracture healing, and accelerates functional recovery of the affected limbs.

Pseudomonas aeruginosa(PA)is an opportunistic pathogen commonly involved in environmental-and difffcult-to-treat nosocomial infection.Currently,multidrug-resistant(MDR)and extensively drug-resistant(XDR)strains of PA are e-merging due to the inappropriate use of antibiotics,which has become a major threat related to healthcare.The antibiotics re-sistance mechanism of PA is very complicated.PA can acquire resistance through mutations in genes encoding for membrane-associated proteins,antibiotics inactivation enzymes and their regulatory proteins,antibiotics target proteins,and two-compo-nent systems.Additionally,resistance genes acquired by horizontal gene transfer(HGT)lead to resistance of PA,which are frequently localized within mobile genetic elements(MGEs),including genes encoding enzymes that inactivate and modify anti-biotics,proteins genes that protect and modify antibiotic targets.In this review,acquired resistance mechanisms of PA involved in gene mutations and HGT was summarized.This review would provide references for the prevention and treatment of PA in-fection,as well as the research and development of new antibiotics.

AIM To investigate the effect of Fuzheng Hefu Zhiyang Formula(FZHFZY)on psoriasis-like skin lesions and immune regulation in mice.METHODS In the in vivo experiment,30 BALB/c mice were randomly divided into the blank group,the model group,the dexamethasone group(1.5 g/kg of compound dexamethasone acetate cream),and the low-dose(2.5 g/kg)and high-dose(5 g/kg)FZHFZY groups,with six mice in each group.The experiment groups were treated with respective FZHFZY and dexamethasone,and the other groups were given normal saline for 10 consecutive days,during which psoriatic skin lesions were induced with imiquimod cream for 7 consecutive days.The mice had their area and severity of psoriasis assessed by PASI score;their histological changes of skin lesions.observed with Hematoxylin-eosin(HE)staining;their F4/80 ratio of skin lesions observed with immunohistochemical(IHC)staining;their protein expressions of P38,p-P38,Erk,p-Erk,P65 and p-P65 detected by Western blot;and their mRNA expressions of tumor necrosis factor-α(TNF-α),IL-17,IL-23 and IL-1β detected by RT-qPCR.In the in vitro research,the cultured RAW264.7 cells were divided into the blank group,the LPS group,and the FZHFZY groups(1 200,600,300,150 μg/mL).The cells had their protein expressions of P38,p-P38,Erk,p-Erk,P65 and p-P65 detected with Western blot;and their mRNA expressions of IL-6,TNF-α,IL-23 and IL-8 detected by RT-qPCR.RESULTS The in vivo experiment showed that compared to the model group,the FZHFZY groups demonstrated decreased PASI score(P＜0.01);improved epidermal thickening and parakeratosis of skin lesions as revealed by HE staining result and increased expression of F4/80 in IHC staining sections;decreased protein expression ratios of p-P38/P38,p-ERK/Erk and p-P65/P65 in skin(P＜0.05,P＜0.01);and reduced mRNA expressions of TNF-α,IL-17,IL-23 and IL-1β in the skin(P＜0.01).FZHFZY(0～2 400 μg/mL)showed no significant cytotoxicity towards RAW264.7 cells in vitro(P＞0.05).Compared to those of the LPS group,the cells exposed to FZHFZ at concentrations of 1 200 and 600 μg/mL demonstrated decreased protein expression ratios of p-P38/P38,p-ERK/Erk,and p-P65/P65(P＜0.05,P＜0.01);and significantly decreased mRNA expressions of TNF-α,IL-17,IL-23 and IL-1β(P＜0.01).CONCLUSION FZHFZY alleviates imiquimod-induced psoriatic lesions in mice and suppresses inflammatory response in LPS-stimulated RAW264.7 cells by inhibiting P38/Erk/NF-κB signaling pathway.

Liquiritigenin(LG)is a flavone of pharmacological importance,however,its application potential is severely limited due to its poor water solubility.LG could be disassociated slightly in water to form phenolate anion,therefore,better solubilization effect is expected by inclusion with cationic cyclodextrins(CCDs).In this work,four kinds of CCDs modified with amino groups at the primary face were synthesized,and their solid inclusion complexes with LG were successfully prepared by preparing their saturated solutions.The formation of the solid inclusion complexes was confirmed by scanning electron microscopy(SEM)and powder X-ray diffraction(PXRD),and their supramolecular binding behavior in solution was studied using multiple techniques.A 1∶1 inclusion stoichiometry of inclusion complexation was defined using Job plot by ultraviolet-visible(UV-vis)spectroscopy,and their binding stability constants(Ks)were determined as 2862.77,3494.70,6521.85 and 9599.48 L/mol using UV-vis spectroscopic titration,far more superior to that of nativeβ-CD(Ks=236.79 L/mol).This indicated that the amino side chains on CCDs could actively participate in the inclusion complexation through anion-cation interactions,significantly strengthening the host-guest binding between CCDs and LG.The inclusion modes were further elucidated based on proton and two-dimensional rotating-frame overhauser enhancement spectroscopy(2D-ROESY)nuclear magnetic resonance(NMR)experiments and molecular docking.Water solubility of LG was dramatically promoted up to 4.9 mg/mL,which was 70-fold higher than that of native LG.This study could draw inspiration for the binding and solubilization of phenols such as flavones by design of cationic macrocyclic molecules.

AIM To investigate the effect of Fuzheng Hefu Zhiyang Formula(FZHFZY)on psoriasis-like skin lesions and immune regulation in mice.METHODS In the in vivo experiment,30 BALB/c mice were randomly divided into the blank group,the model group,the dexamethasone group(1.5 g/kg of compound dexamethasone acetate cream),and the low-dose(2.5 g/kg)and high-dose(5 g/kg)FZHFZY groups,with six mice in each group.The experiment groups were treated with respective FZHFZY and dexamethasone,and the other groups were given normal saline for 10 consecutive days,during which psoriatic skin lesions were induced with imiquimod cream for 7 consecutive days.The mice had their area and severity of psoriasis assessed by PASI score;their histological changes of skin lesions.observed with Hematoxylin-eosin(HE)staining;their F4/80 ratio of skin lesions observed with immunohistochemical(IHC)staining;their protein expressions of P38,p-P38,Erk,p-Erk,P65 and p-P65 detected by Western blot;and their mRNA expressions of tumor necrosis factor-α(TNF-α),IL-17,IL-23 and IL-1β detected by RT-qPCR.In the in vitro research,the cultured RAW264.7 cells were divided into the blank group,the LPS group,and the FZHFZY groups(1 200,600,300,150 μg/mL).The cells had their protein expressions of P38,p-P38,Erk,p-Erk,P65 and p-P65 detected with Western blot;and their mRNA expressions of IL-6,TNF-α,IL-23 and IL-8 detected by RT-qPCR.RESULTS The in vivo experiment showed that compared to the model group,the FZHFZY groups demonstrated decreased PASI score(P＜0.01);improved epidermal thickening and parakeratosis of skin lesions as revealed by HE staining result and increased expression of F4/80 in IHC staining sections;decreased protein expression ratios of p-P38/P38,p-ERK/Erk and p-P65/P65 in skin(P＜0.05,P＜0.01);and reduced mRNA expressions of TNF-α,IL-17,IL-23 and IL-1β in the skin(P＜0.01).FZHFZY(0～2 400 μg/mL)showed no significant cytotoxicity towards RAW264.7 cells in vitro(P＞0.05).Compared to those of the LPS group,the cells exposed to FZHFZ at concentrations of 1 200 and 600 μg/mL demonstrated decreased protein expression ratios of p-P38/P38,p-ERK/Erk,and p-P65/P65(P＜0.05,P＜0.01);and significantly decreased mRNA expressions of TNF-α,IL-17,IL-23 and IL-1β(P＜0.01).CONCLUSION FZHFZY alleviates imiquimod-induced psoriatic lesions in mice and suppresses inflammatory response in LPS-stimulated RAW264.7 cells by inhibiting P38/Erk/NF-κB signaling pathway.

Objective:To compare the clinical efficacy of robot-assisted balloon tibioplasty and traditional open reduction and internal fixation in the treatment of AO/OTA type 41B2 tibial plateau fracture.Methods:A retrospective cohort study was conducted to analyze the clinical data of 70 patients with AO/OTA type 41B2 tibial plateau fracture who were admitted to Wuhan Fourth Hospital from September 2019 to October 2022, including 35 males and 35 females, aged 24-62 years [(44.9±9.5)years]. Among them, 41 patients underwent traditional open reduction and internal fixation (open reduction group), while 29 patients underwent robot-assisted balloon tibioplasty (balloon group). The following parameters were compared between the two groups: incision length, operative blood loss, number of intraoperative fluoroscopies, operation duration, and length of hospital stay; Rasmussen radiological scores at 3 days, 3 months postoperatively, and at the last follow-up and the fracture healing time; pain visual analogue scale (VAS) scores preoperatively, and at 2 days and 3 months postoperatively; knee joint range of motion at 5 days, 3 months postoperatively, and at the last follow-up; Hospital for Special Surgery (HSS) knee function scores at 3, 6 months postoperatively, and at the last follow-up; incidence rate of complications at 15 days postoperatively.Results:All the patients were followed for 12-24 months [18(17, 20)months]. The incision length, operative blood loss and length of hospital stay in the balloon group were 1.6(1.5, 3.0)cm, 5.0(5.0, 5.0)ml and 11.0(9.0, 14.0)days, less than those in the open reduction group [12.0(11.0, 12.0)cm, 100.0(50.0, 120.0)ml and 15.0(13.0, 20.0)days] ( P<0.01). The number of intraoperative fluoroscopies and operation duration in the open reduction group were 9.0(7.0, 10.0)times and 75.0(60.0, 90.0)minutes, less than those in the balloon group [336.0(335.0, 340.0)times and [90.0(70.0, 105.0)minutes] ( P<0.05). There were no significant differences in the Rasmussen radiological scores between the two groups at 3 days, 3 months postoperatively, or at the last follow-up ( P>0.05). The fracture healing time in the balloon group was 3.0(3.0, 3.0)months, shorter than 3.0(3.0, 3.5)months in the open reduction group ( P<0.05). No significant differences were observed between the two groups in VAS scores before operation or at 3 months postoperatively ( P>0.05). However, the VAS score was 2.0(2.0, 3.0)points at 2 days postoperatively in the balloon group, lower than 5.0(5.0, 6.0)points in the open reduction group ( P<0.01). The knee joint range of motion at 5 days, 3 months postoperatively and at the last follow-up were 90.0(85.0, 90.0)°, 135.0(130.0, 135.0)° and 140.0(135.0, 140.0)° in the balloon group, better than 65.0(60.0, 70.0)°, 125.0(120.0, 130.0)°, 130.0(130.0, 140.0)° in the open reduction group ( P<0.01). Similarly, the HSS knee function scores at 3, 6 months postoperatively and at the last follow-up were 80.0(80.0, 81.0)points, 91.0(90.0, 92.0)points, and 95.0(93.0, 96.0)points in the balloon group, better than 71.0(70.0, 72.0)points, 83.0(81.0, 84.0)points, and 86.0(84.0, 88.0)points in the open reduction group ( P<0.01). The incidence rate of complications in the balloon group was 0, comparable to 12% (5/41) in the open reduction group ( P>0.05). Conclusion:Compared with traditional open reduction and internal fixation surgery, robot-assisted balloon tibioplasty in the treatment of AO/OTA type 41B2 tibial plateau fracture significantly reduces surgical trauma, alleviates postoperative pain, promotes fracture healing, and accelerates functional recovery of the affected limbs.

Objective To investigate the clinical characteristics and prognosis of pneumococcal meningitis(PM),and drug sensitivity of Streptococcus pneumoniae(SP)isolates in Chinese children.Methods A retrospective analysis was conducted on clinical information,laboratory data,and microbiological data of 160 hospitalized children under 15 years old with PM from January 2019 to December 2020 in 33 tertiary hospitals across the country.Results Among the 160 children with PM,there were 103 males and 57 females.The age ranged from 15 days to 15 years,with 109 cases(68.1% )aged 3 months to under 3 years.SP strains were isolated from 95 cases(59.4% )in cerebrospinal fluid cultures and from 57 cases(35.6% )in blood cultures.The positive rates of SP detection by cerebrospinal fluid metagenomic next-generation sequencing and cerebrospinal fluid SP antigen testing were 40% (35/87)and 27% (21/78),respectively.Fifty-five cases(34.4% )had one or more risk factors for purulent meningitis,113 cases(70.6% )had one or more extra-cranial infectious foci,and 18 cases(11.3% )had underlying diseases.The most common clinical symptoms were fever(147 cases,91.9% ),followed by lethargy(98 cases,61.3% )and vomiting(61 cases,38.1% ).Sixty-nine cases(43.1% )experienced intracranial complications during hospitalization,with subdural effusion and/or empyema being the most common complication[43 cases(26.9% )],followed by hydrocephalus in 24 cases(15.0% ),brain abscess in 23 cases(14.4% ),and cerebral hemorrhage in 8 cases(5.0% ).Subdural effusion and/or empyema and hydrocephalus mainly occurred in children under 1 year old,with rates of 91% (39/43)and 83% (20/24),respectively.SP strains exhibited complete sensitivity to vancomycin(100% ,75/75),linezolid(100% ,56/56),and meropenem(100% ,6/6).High sensitivity rates were also observed for levofloxacin(81% ,22/27),moxifloxacin(82% ,14/17),rifampicin(96% ,25/26),and chloramphenicol(91% ,21/23).However,low sensitivity rates were found for penicillin(16% ,11/68)and clindamycin(6% ,1/17),and SP strains were completely resistant to erythromycin(100% ,31/31).The rates of discharge with cure and improvement were 22.5% (36/160)and 66.2% (106/160),respectively,while 18 cases(11.3% )had adverse outcomes.Conclusions Pediatric PM is more common in children aged 3 months to under 3 years.Intracranial complications are more frequently observed in children under 1 year old.Fever is the most common clinical manifestation of PM,and subdural effusion/emphysema and hydrocephalus are the most frequent complications.Non-culture detection methods for cerebrospinal fluid can improve pathogen detection rates.Adverse outcomes can be noted in more than 10% of PM cases.SP strains are high sensitivity to vancomycin,linezolid,meropenem,levofloxacin,moxifloxacin,rifampicin,and chloramphenicol.[Chinese Journal of Contemporary Pediatrics,2024,26(2):131-138]

BACKGROUND:Clinical skin wound healing continues to be a significant concern,and tissue repair research has moved to the forefront with the development of biomaterials with immunomodulatory properties.Therefore,it is crucial to research wound dressings that have immunomodulatory properties. OBJECTIVE:To prepare chitosan hydrogels that have been modified by arginine with different configurations and assess their capacity to speed up wound healing in a rat animal model. METHODS:(1)In vitro trial:Chitosan modified by pure L-arginine,pure D-arginine,and L-arginine and D-arginine was synthesized by EDC/NHS system,which was then crosslinked with aldehyde-modified four-arm polyethylene glycol.Different chitosan-based hydrogels(CS-L,CS-D,and CS-DL)were finally formed via the Schiff base reaction.Three kinds of hydrogel extracts were co-cultured with fibroblasts respectively.Hydrogel cytocompatibility was assessed using the CCK-8 assay and live/dead staining.The effect of hydrogel on the migration capacity of fibroblasts was assessed by using a scratch test.Three kinds of hydrogels were incubated with rat erythrocyte suspension respectively to evaluate the hemocompatibility of the hydrogels.The hydrogel extract was co-cultured with RAW264.7 macrophages to test the hydrogels'capacity to enhance macrophage NO generation and polarize macrophage phenotype.(2)In vivo experiment:A total of 36 adult SD rats were divided into 4 groups with 9 rats in each group by the random number table method.Two full-layer skin defect wounds of 2 cm×2 cm were made on the back of each rat.Normal saline was added to the wounds of the control group,and corresponding hydrogel was added to the wounds of the CS-L,CS-D,and CS-DL groups,respectively,and then bandaged and fixed.The wound healing was observed regularly after operation.Hematoxylin-eosin staining was performed at 3,10,and 21 days after operation.The samples were collected 10 days after operation and M2 macrophage immunofluorescence staining was performed. RESULTS AND CONCLUSION:(1)In vitro experiments:Under scanning electron microscopy,the three kinds of hydrogels exhibited obvious interpenetrating network structures with pore sizes ranging from 70-200 μm.The three kinds of hydrogels have good swelling performance,degradation performance,self-healing performance,and suitable mechanical strength.The three kinds of hydrogels had good cytocompatibility and hemocompatibility and could promote the migration of fibroblasts.All three kinds of hydrogels had the ability to promote the polarization of macrophages,and CS-D hydrogels had the strongest ability to promote the polarization of macrophages.CS-L hydrogel could significantly promote the production of NO in macrophages.(2)In vivo experiment:3 and 10 days after operation,the wound healing rate in the CS-L and CS-D groups was higher than that in the control group(P<0.05).After 21 days,the wound healing rate of the three hydrogel groups was higher than that of the control group.Hematoxylin-eosin staining displayed that a large number of inflammatory cells were infiltrated in the wound tissue of rats in all groups,accompanied by neovessels and fibroblasts 3 days after operation.10 days after operation,there was still more inflammatory cell infiltration in the wound of the control group,and the inflammation of the other three groups was improved,especially the decrease of inflammatory cells in the CS-D group was more obvious.21 days after operation,the wound epithelium of each group was well repaired,and there was basically no inflammatory cell infiltration in the CS-L and CS-D groups,while there was still a small amount of inflammatory cell infiltration in the control group.Immunofluorescence staining revealed that the number of M2-type macrophages in the CS-D group was higher than that in the other three groups(P<0.05).(3)The results conclude that chitosan hydrogels modified by different configurations of arginine can promote wound healing through different mechanisms.

Objective:To investigate the etiology, clinical features and treatment of familial exudative vitreoretinopathy (FEVR) secondary glaucoma.Methods:A retrospective clinical study. From January 1, 2016 to January 1, 2022, 15 patients (17 eyes) were diagnosed with FEVR secondary glaucoma in Beijing Tongren Hospital, Capital Medical University were included in the study. All patients underwent systematic ophthalmological evaluation. According to the patient's age, visual acuity, intraocular pressure, anterior segment, vitreous body and retina condition, the choice of translimbal lensectomy combined with vitrectomy, goniectomy, cyclophotocoagulation, intravitreal injection of anti-vascular endothelial growth factor (VEGF) treatment were chosen. The follow-up time was 3 to 37 months. The clinical characteristics of the affected eye, and the changes of intraocular pressure, anterior chamber depth and complications after surgery were observed.Results:Among the 15 patients, there were 11 males with 13 eyes, and 4 females with 4 eyes. Age was 6.14±7.37 years old. FEVR stages 2B, 3B, 4A, 4B, 5A, and 5B were 1, 1, 5, 6, 3, and 1 eye, respectively. The intraocular pressure of the affected eye was 42.74±9.06 mm Hg (1 mm Hg=0.133 kPa). All eyes had shallow anterior chamber and angle closure, anterior or posterior iris adhesions, lens opacity, retinal detachment, iris neovascularization in 4 eyes, and vitreous hemorrhage in 2 eyes. Sixteen eyes were treated with translimbal lensectomy combined with vitrectomy and goniotomy, of which 8 eyes were treated with anti-VEGF treatment; 1 eye was treated with cyclophotocoagulation combined with anti-VEGF treatment. After operation, the intraocular pressure of 16 eyes returned to normal range, and the depth of anterior chamber of 16 eyes returned to normal, and no obvious complications occurred.Conclusions:The main etiology of secondary glaucoma in FEVR is the structural and functional abnormalities of the anterior chamber and angle, which are found in the 2B and above stages of FEVR. The lensectomy and vitrectomy via limbal approach can effectively control the intraocular pressure and restore the anterior chamber, with no serious complications.