[A multicenter prospective study on early identification of refractory Mycoplasma pneumoniae pneumonia in children]

Objective: To explore potential predictors of refractory Mycoplasma pneumoniae pneumonia (RMPP) in early stage. Methods: The prospective multicenter study was conducted in Zhejiang, China from May 1st, 2019 to January 31st, 2020. A total of 1 428 patients with fever >48 hours to <120 hours were studied. Their clinical data and oral pharyngeal swab samples were collected; Mycoplasma pneumoniae DNA in pharyngeal swab specimens was detected. Patients with positive Mycoplasma pneumoniae DNA results underwent a series of tests, including chest X-ray, complete blood count, C-reactive protein, lactate dehydrogenase (LDH), and procalcitonin. According to the occurrence of RMPP, the patients were divided into two groups, RMPP group and general Mycoplasma pneumoniae pneumonia (GMPP) group. Measurement data between the 2 groups were compared using Mann-Whitney U test. Logistic regression analyses were used to examine the associations between clinical data and RMPP. Receiver operating characteristic (ROC) curves were used to analyse the power of the markers for predicting RMPP. Results: A total of 1 428 patients finished the study, with 801 boys and 627 girls, aged 4.3 (2.7, 6.3) years. Mycoplasma pneumoniae DNA was positive in 534 cases (37.4%), of whom 446 cases (83.5%) were diagnosed with Mycoplasma pneumoniae pneumonia, including 251 boys and 195 girls, aged 5.2 (3.3, 6.9) years. Macrolides-resistant variation was positive in 410 cases (91.9%). Fifty-five cases were with RMPP, 391 cases with GMPP. The peak body temperature before the first visit and LDH levels in RMPP patients were higher than that in GMPP patients (39.6 (39.1, 40.0) vs. 39.2 (38.9, 39.7) ℃, 333 (279, 392) vs. 311 (259, 359) U/L, both P<0.05). Logistic regression showed the prediction probability π=exp (-29.7+0.667×Peak body temperature (℃)+0.004×LDH (U/L))/(1+exp (-29.7+0.667×Peak body temperature (℃)+0.004 × LDH (U/L))), the cut-off value to predict RMPP was 0.12, with a consensus of probability forecast of 0.89, sensitivity of 0.89, and specificity of 0.67; and the area under ROC curve was 0.682 (95%CI 0.593-0.771, P<0.01). Conclusion: In MPP patients with fever over 48 to <120 hours, a prediction probability π of RMPP can be calculated based on the peak body temperature and LDH level before the first visit, which can facilitate early identification of RMPP.

Phage P2-71 against multi-drug resistant Proteus mirabilis: isolation, characterization, and non-antibiotic antimicrobial potential

Proteus mirabilis, a prevalent urinary tract pathogen and formidable biofilm producer, especially in Catheter-Associated Urinary Tract Infection, has seen a worrying rise in multidrug-resistant (MDR) strains. This upsurge calls for innovative approaches in infection control, beyond traditional antibiotics. Our research introduces bacteriophage (phage) therapy as a novel non-antibiotic strategy to combat these drug-resistant infections. We isolated P2-71, a lytic phage derived from canine feces, demonstrating potent activity against MDR P. mirabilis strains. P2-71 showcases a notably brief 10-minute latent period and a significant burst size of 228 particles per infected bacterium, ensuring rapid bacterial clearance. The phage maintains stability over a broad temperature range of 30-50°C and within a pH spectrum of 4-11, highlighting its resilience in various environmental conditions. Our host range assessment solidifies its potential against diverse MDR P. mirabilis strains. Through killing curve analysis, P2-71's effectiveness was validated at various MOI levels against P. mirabilis 37, highlighting its versatility. We extended our research to examine P2-71's stability and bactericidal kinetics in artificial urine, affirming its potential for clinical application. A detailed genomic analysis reveals P2-71's complex genetic makeup, including genes essential for morphogenesis, lysis, and DNA modification, which are crucial for its therapeutic action. This study not only furthers the understanding of phage therapy as a promising non-antibiotic antimicrobial but also underscores its critical role in combating emerging MDR infections in both veterinary and public health contexts.

[Characteristics and changes of cardiac injury with age in children of Duchenne muscular dystrophy: a prospective cohort study]

Objective: To explore the characteristics and changes of cardiac injury with age in Duchenne muscular dystrophy (DMD) and its clinical significance. Methods: A prospective cohort study was conducted. The 215 patients diagnosed with DMD in West China Second Hospital from January 2019 to November 2022 and aged from 6 to 18 years were enrolled. Their clinical data, myocardial injury markers, routine electrocardiogram, cardiac magnetic resonance (CMR) and echocardiography were collected. The patients were divided into five age groups: 6-<8, 8-<10, 10-<12, 12-<14 and 14-18 years of age, and matched with healthy boys respectively. Independent sample t test or Mann-Whitney U test was used to compare the clinical data and CMR indexes between DMD patients and controls in all age subgroups, and to compare the value of left ventricular ejection fraction (LVEF) measured by echocardiography and CMR in each subgroup of DMD patitents. Pearson correlation analysis or Spearman correlation analysis was used to explore the relation between the CMR indexes and age in DMD patients. Results: A total of 215 patients with DMD (all male) and 122 healthy boys were included in the study. There were 75 DMD patients and 23 controls in 6-<8 years of age group, 77 DMD and 28 controls in 8-<10 years of age group, 39 DMD and 23 controls in 10-<12 years of age group, 10 DMD and 31 controls in the 12-<14 years of age group, and 14 DMD and 17 controls in 14-18 years of age group. In the DMD patients, the older the age, the lower the levels of creatine kinase (CK) and creatine kinase isoenzyme (CK-MB). In the 6-<8 years of age group, the CK level was 10 760 (7 800, 15 757) U/L, while in the group of 14-18 years of age, it was 2 369 (1 480, 6 944) U/L. As for CK-MB, it was (189±17) μg/L in the 6-<8 years of age group and (62±16) μg/L in the 14-18 years of age group. Cardiac troponin I remained unchanged in <12 years of age groups, but significantly increased in 12-<14 years of age group, reaching the highest value of 0.112 (0.006, 0.085) μg/L. In the DMD patients, the older the age, the higher the proportion of abnormal electrocardiogram (ECG). In the 6-<8 years of age group, the proportion is 29.3% (22/75), while in the 14-18 years of age group, it was 10/14. Correlation analysis showed that the left ventricular end-diastolic volume index was positively related with age (r=0.18, P=0.015), and the left ventricular stroke volume index and cardiac output index were negatively related with age (r=-0.34 and -0.31, respectively, both P<0.001). In the DMD patients, the older the age, the lower LVEF, with the LVEF decreasing to (49.3±3.1)% in the 14-18 years of age group. The LVEF of DMD cases was significantly lower than that of controls in the age subgroups of 8-<10, 10-<12, 12-<14 and 14-18 years of age groups ((57.9±5.2) % vs. (63.6±0.8)%, 60.7% (55.9%, 61.9%) vs. 63.7% (60.2%, 66.0%), 57.1% (51.8%, 63.4%) vs. 62.1 % (59.5%, 64.5)%, (49.3±3.1) % vs. (61.6±1.3)%, respectively; all P<0.01). In the DMD patients, the older the age, the higher the proportion of positive late gadolinium enhancement (LGE). In the 6-<8 years of age group, it was 22% (11/51), in the 12-<14 years of age group, it was 13/14, and in the 14-18 years of age group, all DMD showed positive LGE. The value of LVEF of DMD cases measured by echocardiography was significantly higher than that measured by CMR in 6-<8 years of age group and 8-<10 years of age group (63.2% (60.1%, 66.4%) vs. 59.1 % (55.4%, 62.9%), and (62.8±5.2) % vs. (57.9±5.2)%, all P<0.001). Conclusion: DMD patients develop cardiac injury in the early stage of the disease, and the incidence of cardiac damage gradually increases with both age and the progression of disease.

[The method of determination for 2, 3-Butanedione in the air of workplace by high performance liquid chromatography with derivatization]

Objective: To establish a method for the determination of 2, 3-Butanedione (BUT) in the air of workplace, which including the process of collection by absorption in phosphoric acid aqueous solution and the process of analysis and detection by high performance liquid chromatography with derivatization. Methods: In October 2022, a porous glass plate absorption tube containing 10 ml of 0.01% phosphoric acid solution was used to collect BUT in the air of the workplace at a flow rate of 0.2 L/min. The absorption solution was derived by 2, 4-dinitrophenylhydrazine for 75 min and separated on a SB-C18 column (250 mm×4.6 mm, 5 μm) . At the column temperature of 30 ℃, the mixture of acetonitrile-water (V∶V, 1∶1) was eluted at the flow rate of 1.0 ml/min. It was detected by UV detector (λ=365 nm) , qualitatived by retention time and quantitatived by external standard. Results: It showed that BUT in phosphoric acid aqueous solution could be stored for at least 7 d at 4 ℃. There was a linear relationship within the determination range of 0.05-6.00 μg/ml, the linear regression equation was y=89.610x+0.133, r=0.9999. The sampling absorption efficiencies were 98.33%-100.00%, the detection limit of the method was 0.005 μg/ml, the minimum detection concentration was 0.016 mg/m(3) (based on V(0)=3.0 L) . The recovery rates were 95.96%-102.44%, the intra batch precision were 4.36%-7.78%, and the inter batch precision were 4.96%-6.06%. Conclusion: The method has the advantages of simple operation, high sensitivity and good accuracy. It can prevent the loss and degradation of BUT. It can be used for the determination of BUT in the air of workplace.

[Application of Delphi method and analytic hierarchy process to construct the evaluation index system of healthy enterprises]

Objective: Explore the application of Delphi method and analytic hierarchy process to explore the construction of scientific, objective and comprehensive evaluation index system for healthy enterprise construction and promote the construction of healthy enterprises. Methods: In October 2022, through Delphi expert consultation and analytic hierarchy process, the indexes were screened and the weights of the indexes were determined, and the evaluation index system of healthy enterprises was established. Results: The positive coefficients of experts in the two rounds were all 100.00%, the authority coefficient of experts was 0.82, the coefficients of variation of the indexes in the two rounds were all less than 0.30. The coordination coefficients of experts in the first and second rounds were 0.64 and 0.77, respectively (P<0.001) . After two rounds of Delphi method expert consultation, a healthy enterprise evaluation index system including 4 first-level indexes, 14 second-level indexes, and 63 third-level indexes was constructed. Conclusion: The constructed health enterprise evaluation index system is highly scientific and reliable, covering the main factors of healthy enterprise construction, and providing a reliable and quantifiable basis and self-assessment basis for the establishment of healthy enterprises.

Enhancement of dissolution rate and oral bioavailability of poorly soluble drug florfenicol by using solid dispersion and effervescent disintegration technology

OBJECTIVE

Florfenicol(FF) is an excellent veterinary antibiotic, limited by poor solubility and poor bioavailability.

SIGNIFICANCE

Here in, we aimed to explore the applicability of fast disintegrating tablets compressed from Florfenicol-loaded solid dispersions (FF-SD-FDTs) to improve the dissolution rate and oral bioavailability of Florfenicol.

METHODS

Utilizing selecting appropriate preparation methods and carriers, the solid dispersions of Florfenicol (FF-SDs) were prepared by solvent evaporation and the fast disintegrating tablets (FF-SD-FDTs) were prepared by the direct compression (DC) method.

RESULTS

The tablet properties including hardness, friability, disintegration time, weight variation, etc. all met the specifications of Chinese Veterinary Pharmacopeia(CVP). FF-SD-FDTs significantly improved drug dissolution and dispersion of FF in vitro compared to florfenicol conventional tablets (FF-CTs). A pharmacokinetics study in German shepherd dogs proved the AUC0-∞ and Cmax values of FF-SD-FDTs are 1.38 and 1.38 times more than FF-CTs, respectively.

CONCLUSIONS

Overall, it can be concluded that FF-SD-FDTs with excellent disintegration and dissolution properties were successfully produced, which greatly improved the oral bioavailability of the poorly soluble drug FF, and the study provided a new idea for a broader role of FF in pet clinics.

Rhamnolipid Micelles Assist Azithromycin in Efficiently Disrupting Staphylococcus aureus Biofilms and Impeding Their Re-Formation

Introduction

Biofilm is highly resistant to antibiotics due to its heterogeneity and is implicated in over 80% of chronic infections; these refractory and relapse-prone infections pose a huge medical burden.

Methods

In this study, rhamnolipid (RHL), a biosurfactant with antibiofilm activity, was loaded with the antibiotic azithromycin (AZI) to construct a stable nanomicelle (AZI@RHL) that promotes Staphylococcus aureus (S. aureus) biofilm disruption.

Results

AZI@RHL micelles made a destruction in biofilms. The biofilm biomasses were reduced significantly by 48.2% (P<0.05), and the main components polysaccharides and proteins were reduced by 47.5% and 36.8%, respectively. These decreases were about 3.1 (15.9%), 7.3 (6.5%), and 1.9 (19.5%) times higher compared with those reported for free AZI. The disruption of biofilm structure was observed under a confocal microscope with fluorescent labeling, and 48.2% of the cells in the biofilm were killed. By contrast, the clearance rates of cells were only 20% and 17% when treated alone with blank micelles or free AZI. Biofilm formation was inhibited up to 92% in the AZI@RHL group due to effects on cell auto-aggregation and eDNA release. The rates for the other groups were significantly lower, with only 27.7% for the RHL group and 12% for the AZI group (P<0.05). The low cell survival and great formation inhibition could reduce biofilm recolonization and re-formation.

Conclusion

The antibiofilm efficacy of rhamnolipid was improved through micellar nanoparticle effects when loading azithromycin. AZI@RHL provides a one-step solution that covers biofilm disruption, bacteria inactivation, recolonization avoidance, and biofilm re-formation inhibition.

The Role of Radiotherapy in Patients with Refractory Hodgkin Lymphoma after Brentuximab Vedotin and -/or Immune Checkpoint Inhibitors

PURPOSE/OBJECTIVE(S)

Brentuximab vedotin (BV) and immune checkpoint inhibitors (ICIs) had important roles in the treatment of relapse or refractory (R/R) Hodgkin lymphoma (HL). Treatment of refractory disease after BV and -/or ICIs remains a challenge. This study was conducted to evaluate the efficacy and safety of radiotherapy for R/R HL after failure to BV or ICIs.

MATERIALS/METHODS

We retrospectively analyzed patients in two institutions with R/R HL who had failed after first-line therapy, and were refractory to BV or ICIs, and received radiotherapy (RT) thereafter. The overall response rate (ORR), duration of response (DOR), progression-free survival (PFS) and overall survival (OS) were analyzed.

RESULTS

A total of 19 patients were enrolled. First-line systemic therapy consisted of ABVD (84.2%), AVD + ICIs (10.5%) and BEACOPP (5.3%), respectively. After first-line therapy, 15 patients (78.9%) were refractory, and 4 patients (21.1%) relapsed. After diagnosis of R/R HL, 8 patients (42.1%) received BV, and 17 patients (89.5%) received ICIs. RT was delivered in all 19 patients who failed after BV or ICIs. In 16 efficacy-evaluable patients, the ORR and CR rate were 100% and 100%. The median DOR was 17.2 months (range, 7.9 to 46.7 months). 3 patients progressed at outside of the radiation field. The in-field-response rate was 100%. The 12-month PFS and OS were 84.4% and 100%, respectively. No patients were reported with sever adverse events.

CONCLUSION

This study concluded that radiotherapy was effective and safe for refractory HL after BV or ICIs. Further prospective studies were warranted.

Association between Phenotypes of Antimicrobial Resistance, ESBL Resistance Genes, and Virulence Genes of Salmonella Isolated from Chickens in Sichuan, China

The aim of this study was to explore the association between antimicrobial resistance, ESBL genes, and virulence genes of Salmonella isolates. From 2019 to 2021, a total of 117 Salmonella isolates were obtained from symptomatic chickens in Sichuan Province, China. The strains were tested for antimicrobial resistance and the presence of ESBL according to the Clinical and Laboratory Standards Institute (CLSI) instructions. The presence of ESBL genes and genes for virulence was determined using Polymerase Chain Reaction (PCR). In addition, Multilocus Sequence Typing (MLST) was applied to confirm the molecular genotyping. Moreover, the mechanism of ESBL and virulence gene transfer and the relationships between the resistance phenotype, ESBL genes, and virulence genes were explored. The isolates exhibited different frequencies of resistance to antibiotics (resistance rates ranged from 21.37% to 97.44%), whereas 68.38% and 41.03% of isolates were multi-drug resistance (MDR) and ESBL-producers, respectively. In the PCR analysis, blaCTX-M was the most prevalent ESBL genotype (73.42%, 58/79), and blaCTX-M-55 showed the most significant effect on the resistance to cephalosporins as tested by logistic regression analysis. Isolates showed a high carriage rate of invA, avrA, sopB, sopE, ssaQ, spvR, spvB, spvC, stn, and bcfC (ranged from 51.28% to 100%). MLST analysis revealed that the 117 isolates were divided into 11 types, mainly ST92, ST11, and ST3717. Of 48 ESBL-producers, 21 transconjugants were successfully obtained by conjugation. Furthermore, ESBL and spv virulence genes were obtained simultaneously in 15 transconjugants. These results highlighted that Salmonella isolates were common carriers of ESBLs and multiple virulence genes. Horizontal transfer played a key role in disseminating antimicrobial resistance and pathogenesis. Therefore, it is necessary to continuously monitor the use of antimicrobials and the prevalence of AMR and virulence in Salmonella from food animals and to improve the antibiotic stewardship for salmonellosis.

[The application value of metagenomic next-generation sequencing technology in diagnosis and treatment of pulmonary infection in immunocompromised patients]

Objective: To evaluate the application value of metagenomic next-generation sequencing (mNGS) in the diagnosis and treatment of pulmonary infection in immunocompromised patients. Methods: A total of 78 patients with immunocompromised pulmonary infection [55 males and 23 females, aged (50.3±16.9) years] and 61 patients with non-immunocompromised pulmonary infection [42 males and 19 females, aged (63.6±15.9) years] in the Intensive Care Unit of the First Medical Center of College of the Pulmonary & Critical Care Medicine, Chinese PLA General Hospital from November 2018 to May 2022 were retrospectively selected. Patients in both groups received bronchoalveolar lavage fluid (BALF) mNGS and conventional microbiological tests (CMTs) while clinically diagnosed with pulmonary infection. The diagnostic positive rate, pathogen detection rate and clinical coincidence rate of the two methods were compared. At the same time, the difference of adjustment rate of anti-infective treatment strategy based on the results of mNGS detection was compared between the two groups. Results: The positive rates of mNGS in patients with pulmonary infection were 94.9% (74/78) and 82.0% (50/61) in the immunocompromised group and the non-immunocompromised group, respectively. The positive rates of CMTs in patients with pulmonary infection were 64.1% (50/78) and 75.4% (46/61) in the immunocompromised group and the non-immunocompromised group, respectively. The positive rates of mNGS and CMTs in patients with pulmonary infection in immunocompromised group showed a statistically significant difference (P<0.001). The detection rates of mNGS in the immunocompromised group for pneumocystis jirovecii and cytomegalovirus were 41.0% (32/78) and 37.2% (29/78), respectively, and the detection rates of Klebsiella pneumoniae, chlamydia psittaci and Legionella pneumophila were 16.4% (10/61), 9.8% (6/61) and 8.2% (5/61) in the non-immunocompromised patients, respectively, which were higher than those of CMTs [1.3% (1/78), 7.7% (6/78), 4.9% (3/61), 0 and 0] (all P<0.05). In the immunocompromised group, the clinical coincidence rates of mNGS and CMTs and were 89.7% (70/78) and 43.6% (34/78), respectively, with a statistically significant difference (P<0.001). In the non-immunocompromised group, the clinical coincidence rates of mNGS and CMTs were 83.6% (51/61) and 62.3% (38/61), with a statistically significant difference (P=0.008). In the immunocompromised group, according to the results of the etiology of mNGS, the adjustment rate of anti-infection treatment strategy was 87.2% (68/78), while in the non-immunocompromised group, the adjustment rate of anti-infective treatment strategy was 60.7% (37/61), with a statistically significant difference (P<0.001). Conclusion: In patients with immunocompromised pulmonary infection, mNGS has more advantages than CMTs in diagnostic positive rate, diagnosis rate of mixed infection, pathogen detection rate and guidance of anti-infection treatment strategy adjustment, which is worthy of clinical promotion and application.

Protective Effects of Bacillus subtilis HH2 against Oral Enterotoxigenic Escherichia coli in Beagles

This study evaluated the protective effect of Bacillus subtilis HH2 on beagles orally challenged with enterotoxigenic Escherichia coli (ETEC). We assessed the physiological parameters and the severity of diarrhea, as well as the changes in three serum immunoglobulins (IgG, IgA, and IgM), plasma diamine oxidase (DAO), D-lactate (D-LA), and the fecal microbiome. Feeding B. subtilis HH2 significantly reduced the severity of diarrhea after the ETEC challenge (p < 0.05) and increased serum levels of IgG, IgA, and IgM (p < 0.01). B. subtilis HH2 administration also reduced serum levels of DAO at 48 h after the ETEC challenge (p < 0.05), but no significant changes were observed in D-LA (p > 0.05). Oral ETEC challenge significantly reduced the richness and diversity of gut microbiota in beagles not pre-fed with B. subtilis HH2 (p < 0.05), while B. subtilis HH2 feeding and oral ETEC challenge significantly altered the gut microbiota structure of beagles (p < 0.01). Moreover, 14 days of B. subtilis HH2 feeding reduced the relative abundance of Deinococcus-Thermus in feces. This study reveals that B. subtilis HH2 alleviates diarrhea caused by ETEC, enhances non-specific immunity, reduces ETEC-induced damage to the intestinal mucosa, and regulates gut microbiota composition.

Isolation, characterization, and pathogenicity assessment of Corynebacterium pseudotuberculosis biovar equi strains from alpacas (Vicugna pacos) in China

Corynebacterium pseudotuberculosis is a zoonotic pathogen that causes lymphadenitis in humans, livestock, and wildlife. In this study, C. pseudotuberculosis biovar equi strains were isolated from three alpacas. Antibiotic susceptibility tests and pathogenicity tests were also conducted. Moreover, one strain was sequenced using DNBSEQ and Oxford Nanopore technology. The three strains exhibited resistance to aztreonam, fosfomycin, and nitrofurantoin. The median lethal doses (LD₅₀) of strains G1, S2 and BA3 in experimentally infected mice was 1.66 × 10⁵ CFU, 3.78 × 10⁵ CFU and 3.78 × 10⁵ CFU, respectively. The sequencing of strain G1 resulted in the assembly of a chromosomal scaffold comprising 2,379,166 bp with a G + C content of 52.06%. Genome analysis of strain G1 revealed the presence of 48 virulence genes and 5 antibiotic resistance genes (ARGs). Comparative genomic analysis demonstrates a high degree of genetic similarity among C. pseudotuberculosis strains, in contrast to other Corynebacterium species, with a clear delineation between strains belonging to the two biovars (ovis and equi). The data of the present study contribute to a better understanding of the properties of C. pseudotuberculosis biovar equi strains and the potential risk they pose to alpacas and other livestock, as well as the necessity of ongoing surveillance and monitoring of infectious diseases in animals.

Preparation, characterization and protective effect of chitosan - Tripolyphosphate encapsulated dihydromyricetin nanoparticles on acute kidney injury caused by cisplatin

Dihydromyricetin (DMY) is a natural dihydroflavonol compound known for its diverse pharmacological benefits. However, its limited stability and bioavailability posed significant challenges for further applications. To address these issues, in this study, an ion crosslinking method was utilized to prepare chitosan nanoparticles that were loaded with DMY. The synthesized chitosan nanoparticles (CS-DMY-NPs) were spherical in shape with particle size and ζ potential of 198.7 nm and 45.05 mV, respectively. Furthermore, in vitro release experiments demonstrated that CS-DMY-NPs had sustained release and protective effects in simulated gastric and intestinal fluids. CS-DMY-NPs exhibited better antioxidant activity by ABTS and DPPH radical scavenging activity than free DMY. In vivo study showed that CS-DMY-NPs alleviated cisplatin-induced kidney damage by inhibiting oxidative stress and proinflammatory cytokines, and had better activity compared to DMY (free). Immunofluorescence data showed that CS-DMY-NPs activated the Nrf2 signaling pathways in a dose-dependent manner to combat cisplatin-induced kidney damage. Our results demonstrate that CS-TPP has good compatibility with DMY, and CS-DMY-NPs exhibited better protective effects against cisplatin-induced acute kidney injury (AKI) than free DMY.

[The mediating effect of resilience on anxiety and subjective well-being in occupational population]

Objective: To explore the current situation of anxiety, subjective well-being in occupational population and the mediating effect of resilience. Methods: From March 24th to 26th, 2020, a cross-sectional survey was conducted among occupational population aged ≥18 years old using online questionnaires. A total of 2134 valid questionnaires were obtained, with respondents from 30 provinces, autonomous regions, and municipalities directly under the Central Government. Their general demographic data, subjective well-being, anxiety, and resilience were collected. Pearson χ(2) test and Spearson correlation analysis were used for data analysis, and structural equation model was used to explore the mediating effect of resilience on anxiety and subjective well-being. Results: The age of the respondents ranged from 18 to 60 years old, with an average age of (31.19±7.09) years old, including 1075 (50.4%) women and 1059 (49.6%) men. The positive rates of low subjective well-being and anxiety were 46.5% (992/2134) and 28.4% (607/2134), respectively. Anxiety scores were significantly negatively correlated with subjective well-being scores and resilience scores (r(s)=-0.52, -0.41, P<0.05), while resilience was significantly positively correlated with subjective well-being (r(s)=0.32, P<0.05). Structural equation models showed that anxiety had a negative predictive effect on subjective well-being, while resilience not only had a positive predictive effect on subjective well-being, but also played a mediating role between anxiety and subjective well-being, with a mediating effect of 9.9%. Conclusion: The situation of anxiety and well-being in the occupational population is still not optimistic, and resilience has a mediating effect between anxiety and subjective well-being.

The Pathophysiological Changes and Clinical Effects of Tetramethylpyrazine in ICR Mice with Fluoride-Induced Hepatopathy

The excessive intake of fluoride, one of the trace elements required to maintain health, leads to liver injury. Tetramethylpyrazine (TMP) is a kind of traditional Chinese medicine monomer with a good antioxidant and hepatoprotective function. The aim of this study was to investigate the effect of TMP on liver injury induced by acute fluorosis. A total of 60 1-month-old male ICR mice were selected. All mice were randomly divided into five groups: a control (K) group, a model (F) group, a low-dose (LT) group, a medium-dose (MT) group, and a high-dose (HT) group. The control and model groups were given distilled water, while 40 mg/kg (LT), 80 mg/kg (MT), or 160 mg/kg (HT) of TMP was fed by gavage for two weeks, with a maximum gavage volume for the mice of 0.2 mL/10 g/d. Except for the control group, all groups were given fluoride (35 mg/kg) by an intraperitoneal injection on the last day of the experiment. The results of this study showed that, compared with the model group, TMP alleviated the pathological changes in the liver induced by the fluoride and improved the ultrastructure of liver cells; TMP significantly decreased the levels of ALT, AST, and MDA (p < 0.05) and increased the levels of T-AOC, T-SOD, and GSH (p < 0.05). The results of mRNA detection showed that TMP significantly increased the mRNA expression levels of Nrf2, HO-1, CAT, GSH-Px, and SOD in the liver compared with the model group (p < 0.05). In conclusion, TMP can inhibit oxidative stress by activating the Nrf2 pathway and alleviate the liver injury induced by fluoride.

Comparison of the effect of zinc oxide nanoparticles and extract of Acorus calamus applied topically on surgical wounds inflicted on the skin of rabbits

Antibiotics are used for postsurgical wound healing purposes but unfortunately, resistance against them demands some alternatives for quick recovery. Sepsis of wounds is a challenge for medical as well as veterinary professionals. Nanoparticles have significant advantages in wound treatment and drug resistance reversal. This study was conducted to appreciate emerging alternates of antibiotics like zinc oxide nanoparticles and plant extracts in topical application. Zinc oxide is considered a good wound healer and its nanoparticles are easy to access. So, the efficacies of zinc oxide nanoparticles and sweet flag plant extract ointments were tested to compare modern and traditional therapeutics as sweet flag is considered a pure medicinal plant. Rabbits were selected for this study due to the healing properties of their skin. Wounds were inflicted on the thoracolumbar region and treated for 29 days post-surgically daily with normal saline and the ointment of zinc oxide nanoparticles and sweet flag extract ointment, prepared in a hydrophilic solvent. Wound shrinkage was observed daily and histopathological analysis was made and results were compared. Zinc oxide nanoparticles ointment showed the most satisfactory results for every parameter included in the study. No side effects of its topical application were observed. Healing was normal without any complications. The preparations of zinc oxide nanoparticles may help in the era of antibiotic resistance as topical drugs in the future.

[A prospective study on the safety and efficacy of excimer laser coronary angioplasty for the treatment of degenerated great saphenous vein graft]

Objective: To explore the safety and efficacy of excimer laser coronary angioplasty (ELCA) for the treatment of degenerated great saphenous vein graft (SVG). Methods: This is a single-center, prospective, single-arm study. Patients, who were admitted to the Geriatric Cardiovascular Center of Beijing Anzhen Hospital from January 2022 to June 2022, were consecutively enrolled. Inclusion criteria were recurrent chest pain after coronary artery bypass surgery (CABG), and coronary angiography confirmed that the SVG stenosis was more than 70% but not completely occluded, and interventional treatment for SVG lesions was planned. Before balloon dilation and stent placement, ELCA was used to pretreat the lesions. Optical coherence tomography (OCT) examination was performed and postoperative index of microcirculation resistance (IMR) were assessed after stent implantation. The technique success rate and operation success rate were calculated. The technique success was defined as the successful passage of the ELCA system through the lesion. Operation success was defined as the successful placement of a stent at the lesion. The primary evaluation index of the study was IMR immediately after PCI. Secondary evaluation indexes included thrombolysis in myocardial infarction (TIMI) flow grade, corrected TIMI frame count (cTFC), minimal stent area and stent expansion measured by OCT after PCI, and procedural complications (Ⅳa myocardial infarction, no reflow, perforation). Results: A total of 19 patients aged (66.0±5.6) years were enrolled, including 18 males (94.7%). The age of SVG was 8 (6, 11) years. The length of the lesions was greater than 20 mm, and they were all SVG body lesions. The median stenosis degree was 95% (80%, 99%), and the length of the implanted stent was (41.7±16.3)mm. The operation time was 119 (101, 166) minutes, and the cumulative dose was 2 089 (1 378, 3 011)mGy. The diameter of the laser catheter was 1.4 mm, the maximum energy was 60 mJ, and the maximum frequency was 40 Hz. The technique success and the operation success rate were both 100% (19/19). The IMR after stent implantation was 29.22±5.95. The TIMI flow grade of patients after ELCA and stent implantation was significantly improved (all P>0.05), and the TIMI flow grade of all patients after stent implantation was Grade Ⅲ. The cTFC decreased significantly after ELCA (33.2±7.8) and after stent placement (22.8±7.1) than preoperative level (49.7±13.0) (both P<0.001). The minimum stent area was (5.53±1.36)mm², and the stent expansion rate was (90.0±4.3)%. Perforation, no reflow, type Ⅳa myocardial infarction and other complications were not observed. However, postoperative high-sensitivity troponin level was significantly increased ((67.937±33.839)ng/L vs. (5.316±3.105)ng/L, P<0.001). Conclusion: ELCA is safe and effective in the treatment of SVG lesions and could improve microcirculation and ensure full expansion of stent.

Pain Relief After Total Knee Arthroplasty with Intravenous and Periarticular Corticosteroid: A Randomized Controlled Trial

BACKGROUND

Total knee arthroplasty (TKA) is a cost-effective procedure, but it is also associated with substantial postoperative pain. The present study aimed to compare pain relief and functional recovery after TKA among groups that received intravenous corticosteroids, periarticular corticosteroids, or a combination of both.

METHODS

This randomized, double-blinded clinical trial in a local institution in Hong Kong recruited 178 patients who underwent primary unilateral TKA. Six of these patients were excluded because of changes in surgical technique; 4, because of their hepatitis B status; 2, because of a history of peptic ulcer; and 2, because they declined to participate in the study. Patients were randomized 1:1:1:1 to receive placebo (P), intravenous corticosteroids (IVS), periarticular corticosteroids (PAS), or a combination of intravenous and periarticular corticosteroids (IVSPAS).

RESULTS

The pain scores at rest were significantly lower in the IVSPAS group than in the P group over the first 48 hours (p = 0.034) and 72 hours (p = 0.043) postoperatively. The pain scores during movement were also significantly lower in the IVS and IVSPAS groups than in the P group over the first 24, 48, and 72 hours (p ≤ 0.023 for all). The flexion range of the operatively treated knee was significantly better in the IVSPAS group than in the P group on postoperative day 3 (p = 0.027). Quadriceps power was also greater in the IVSPAS group than in the P group on postoperative days 2 (p = 0.005) and 3 (p = 0.007). Patients in the IVSPAS group were able to walk significantly further than patients in the P group in the first 3 postoperative days (p ≤ 0.003). Patients in the IVSPAS group also had a higher score on the Elderly Mobility Scale than those in the P group (p = 0.036).

CONCLUSIONS

IVS and IVSPAS yielded similar pain relief, but IVSPAS yielded a larger number of rehabilitation parameters that were significantly better than those in the P group. This study provides new insights into pain management and postoperative rehabilitation following TKA.

LEVEL OF EVIDENCE

Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.

Virulence-related factors and antimicrobial resistance in Proteus mirabilis isolated from domestic and stray dogs

Introduction

Proteus mirabilis is a multi-host pathogen that causes diseases of varying severity in a wide range of mammals, including humans. Proteus mirabilis is resistant to multiple antibiotics and has acquired the ability to produce expanded spectrum of β-lactamases, leading to serious public health problems. However, the available information on P. mirabilis isolated from feces of dogs, is still poorly understood, as is the correlation between its virulence-associated genes (VAGs) and antibiotic resistance genes (ARGs).

Method

In this study, we isolated 75 strains of P. mirabilis from 241 samples, and investigated the swarming motility, biofilm formation, antimicrobial resistance (AMR), distribution of VAGs and ARGs, as well as the presence of class 1, 2, and 3 integrons in these isolates.

Results

Our findings suggest a high prevalence of intensive swarming motility and strong biofilm formation ability among P. mirabilis isolates. Isolates were primarily resistant to cefazolin (70.67%) and imipenem (70.67%). These isolates were found to carry ureC, FliL, ireA, zapA, ptA, hpmA, hpmB, pmfA, rsbA, mrpA, and ucaA with varying prevalence levels of 100.00, 100.00, 100.00, 98.67, 98.67, 90.67, 90.67, 90.67, 90.67, 89.33, and 70.67%, respectively. Additionally, the isolates were found to carry aac(6')-Ib, qnrD, floR, bla_CTX-M, bla_CTX-M-2, bla_OXA-1, bla_TEM, tetA, tetB and tetM with varying prevalence levels of 38.67, 32.00, 25.33, 17.33, 16.00, 10.67, 5.33, 2.67, 1.33, and 1.33%, respectively. Among 40 MDR strains, 14 (35.00%) were found to carry class 1 integrons, 12 (30.00%) strains carried class 2 integrons, while no class 3 integrons was detected. There was a significant positive correlation between the class 1 integrons and three ARGs: bla_TEM, bla_CTX-M, and bla_CTX-M-2. This study revealed that P. mirabilis strains isolated from domestic dogs exhibited a higher prevalence of MDR, and carried fewer VAGs but more ARGs compared to those isolated from stay dogs. Furthermore, a negative correlation was observed between VAGs and ARGs.

Discussion

Given the increasing antimicrobial resistance of P. mirabilis, veterinarians should adopt a prudent approach towards antibiotics administration in dogs to mitigate the emergence and dissemination of MDR strains that pose a potential threat to public health.

[Association between urinary arsenic level and serum testosterone in Chinese men aged 18 to 79 years]

Objective: To investigate the association between the urinary arsenic level and serum total testosterone in Chinese men aged 18 to 79 years. Methods: A total of 5 048 male participants aged 18 to 79 years were recruited from the China National Human Biomonitoring (CNHBM) from 2017 to 2018. Questionnaires and physical examinations were used to collect information on demographic characteristics, lifestyle, food intake frequency and health status. Venous blood and urine samples were collected to detect the level of serum total testosterone, urine arsenic and urine creatinine. Participants were divided into three groups (low, middle, and high) based on the tertiles of creatinine-adjusted urine arsenic concentration. Weighted multiple linear regression was fitted to analyze the association of urinary arsenic with serum total testosterone. Results: The weighted average age of 5 048 Chinese men was (46.72±0.40) years. Geometric mean concentration (95%CI) of urinary arsenic, creatinine-adjusted urine arsenic and serum testosterone was 22.46 (20.08, 25.12) μg/L, 19.36 (16.92, 22.15) μg/L and 18.13 (17.42, 18.85) nmol/L, respectively. After controlling for covariates, compared with the low-level urinary arsenic group, the testosterone level of the participants in the middle-level group and the high-level group decreased gradually. The percentile ratio (95%CI) was -5.17% (-13.14%, 3.54%) and -10.33% (-15.68%, -4.63). The subgroup analysis showed that the association between the urinary arsenic level and testosterone level was more obvious in the group with BMI<24 kg/m² group (P_interaction<0.05). Conclusion: There is a negative association between the urinary arsenic level and serum total testosterone in Chinese men aged 18-79 years.

Oral immunocontraceptive vaccines: A novel approach for fertility control in wildlife

The overabundant populations of wildlife have caused many negative impacts, such as human-wildlife conflicts and ecological degradation. The existing approaches like injectable immunocontraceptive vaccines and lethal methods have limitations in many aspects, which has prompted the advancement of oral immunocontraceptive vaccine. There is growing interest in oral immunocontraceptive vaccines for reasons including high immunization coverage, easier administration, frequent boosting, the ability to induce systemic and mucosal immune responses, and cost-effectiveness. Delivery systems have been developed to protect oral antigens and enhance the immunogenicity, including live vectors, microparticles and nanoparticles, bacterial ghosts, and mucosal adjuvants. However, currently, no effective oral immunocontraceptive vaccine is available for field trials because of the enormous development challenges, including biological and physicochemical barriers of the gastrointestinal tract, mucosal tolerance, pre-existing immunity, antigen residence time in the small intestine, species specificity and other safety issues. To overcome these challenges, this article summarizes achievements in delivery systems and contraceptive antigens in oral immunocontraceptive vaccines and explores the potential barriers for future vaccine design and application.

Senile plaques in Alzheimer's disease arise from Aβ- and Cathepsin D-enriched mixtures leaking out during intravascular haemolysis and microaneurysm rupture

Senile plaques are a pathological hallmark of Alzheimer's disease (AD), yet the mechanism underlying their generation remains unknown. Beta-amyloid peptide (Aβ) is a major component of senile plaques. We analysed AD brain tissues with histochemistry, immunohistochemistry and fluorescence imaging to examine the neural, vascular or blood Aβ contribution to senile plaque development. We found little neural marker co-expression with plaque Aβ, while co-expression of blood markers, such as Haemin and ApoE, was abundant. The plaque cores were structured with vascular and glial proteins outside and blood metabolites inside, co-localizing with a characteristic of Hoechst staining-independent blue autofluorescence. Erythrocyte-interacting Aβ is linked to coagulation, elevated calcium and blue autofluorescence, and it is associated with intravascular haemolysis, atherosclerosis, cerebral amyloid angiopathy, microaneurysm, and often with Cathepsin D co-expression. We identified microaneurysms as major sites of amyloid formation. Our data suggest that senile plaques arise from Aβ- and Cathepsin D-enriched mixtures leaking out during intravascular haemolysis and microaneurysm rupture.

[Comparative study of decompression of unilateral biportal endoscopic compared to laminectomy with fusion and internal fixation in the treatment of severe lumbar spinal stenosis]

Objective: To compare the clinical efficacy of unilateral biportal endoscopy unilateral laminotomy for bilateral decompression (UBE-ULBD) to posterior lumbar interbody fusion (PLIF) in the treatment of severe lumbar spinal stenosis (SLSS). Methods: The clinical data of 64 patients with SLSS treated with PLIF and UBE-ULBD in Dalian Central Hospital Affiliated to Dalian Medical University from April 2018 to April 2021 were collected and divided into UBE group and PLIF group according to the different surgical procedures. There were 30 cases in the UBE group, including 12 males and 18 females, aged (69.8±6.8) years. There were 34 patients in the PLIF group, including 15 males and 19 females, aged (69.3±6.3) years. The operation time, intraoperative blood loss, surgical complications, the volume of drainage, transfusion, post-operative bed rest time, postoperative hospital stay, surgical costs of both groups were recorded and analyzed. The visual analogue scales (VAS) of back/leg pain (pre-operation and 1 d, 1 month, 6 month, 12 month post-operation) and Oswestry disability index (ODI) (pre-operation and 1 month, 6 month, 12 month post-operation) were used to determine the outcome. And the dural sac cross-sectional area (DSCA) and Schizas grade of both groups preoperatively and 6 month postoperatively were recorded. Results: The operation time in the UBE group was (69.2±8.0) min, it was lower than that in the PLIF group (139.0±15.3) min (P<0.05). The intraoperative blood loss and drainage in the UBE group were (19.5±5.6) ml and (15.0±10.8) ml, which were both lower than those in the PILF group [(212.4±34.1) ml and (169.6±43.8) ml] (both P<0.05). The postoperative bed rest time and hospital stay in the UBE group were (1.8±0.7) days and (3.0±0.9) days, which were both shorter than those in the PLIF group [(4.5±1.4) days and (7.1±1.7) days] (both P<0.05). The surgical cost was also lower in the UBE group than that in the PLIF group [RMB,(18.4±1.0) thousands yuan vs (33.9±2.4) thousands yuan, P<0.05]. In addition, no patient received blood transfusion in the UBE group. Dural sac tear occurred in 2 cases in the UBE group and in 3 cases in PLIF group; nerve root injury and infection occurred in one case in the PLIF group, respectively. In the PLIF group, the VAS of back pain was not significantly improved 1 day after operation when compared with that before the operation, but it significantly improved 1 month, 6 months and 1 year after operation (all P<0.05). The VAS for back pain at 1 day after operation and ODI at 1 month after operation in the UBE group were significantly superior to those in the PLIF group (both P<0.05), while there was no significant difference between the two groups in the VAS for back pain at 1 month, 6 months and 1 year after operation and ODI at 6 months and 1 year after operation. Both groups got significant canal expansion after the surgery and the PLIF group showed larger canal expansion extent (all P<0.05). Both groups improved significantly after surgery in the Schizas grade, there were 25 cases in UBE group improved to grade A, 5 cases to grade B while 30 cases in PLIF group improved to grade A, 4 cases to grade B, but there was no significant difference between the two groups (P>0.05). Conclusion: ULBD-UBE could achieve full decompression of the whole spinal canal with limited structures damage in treating SLSS. Compared with PLIF, UBE-ULBD could get complete decompression as well as less iatrogenic damage, it may be an ideal alternative surgical technique for SLSS with less invasion.

Modified Sijunzi granule decreases post-weaning diarrhea in Rex rabbits via promoting intestinal development

Traditional Chinese medicine (TCM) formulas can be adjusted on the basis of TCM basic theory to achieve the best curative effect, especially for diseases with complex pathogenesis, such as post-weaning diarrhea (PWD). Shugan Jianwei Sijunzi decoction (SJ-SJZD) can be recognized as modified Sijunzi Decoction (SJZD) supplemented with Astragalus mongholicus Bunge, Bupleurum chinense DC, Citrus × aurantium L., and Crataegus pinnatifida Bunge (fruit) in a fixed dosage ratio. The inactive ingredients were subsequently added to make granule, which was Shugan Jianwei Sijunzi granule (SJ-SJZG). Previous studies have confirmed the antagonism of SJ-SJZG to PWD. However, the mechanism of SJ-SJZG protective effects on small intestine in weaned Rex rabbits remained unclear. Animals were randomly divided into negative control (NC), low dose (LD), medium dose (MD), high dose (HD), and positive control (PC). SJ-SJZG significantly increased the intestinal length and the jejunum villi length. The SIgA level was statistically increased in duodenum and jejunum with the ELISA. Immunohistochemical detection showed that SIgA protein expression was also increased significantly in jejunum. Meanwhile, the relative expression of Zo1 in duodenum and jejunum of SJ-SJZG group increased significantly. SJ-SJZG significantly increased the relative expression of occludin in duodenum and jejunum as well. Moreover, real-time PCR results showed a significant increase in GLUT2 and SGLT1 relative expression in ileum. SJ-SJZG could also obviously enhance the expression of GLUT2 in jejunum and the expression of SGLT1 in duodenum. In conclusion, SJ-SJZG had been proven to be effective in promoting the development of small intestine and improving the immunity of small intestine. Moreover, SJ-SJZG could ensure the integrity of mucosal barrier and increase the ability of intestine to absorb glucose in small intestine.

The effect of Nickel hypersensitivity on the outcome of total knee arthroplasty and the value of skin patch testing: a systematic review

Background

To assess the Nickel sensitizing potential of total knee arthroplasty (TKA), explore the relationship between hypersensitivity and clinical outcomes, and evaluate the utility of skin patch testing pre- and/or postoperatively.

Materials and methods

A literature search was performed through EMBASE, Medline and PubMed databases. Articles were screened independently by two investigators. The level of evidence of studies was assessed using the Oxford Centre for Evidence-Based Medicine Criteria and the quality evaluated using the Methodological Index for Non-randomized Studies and Cochrane risk-of-bias tools.

Results

Twenty studies met the eligibility criteria, reporting on 1354 knee arthroplasties. Studies included patients undergoing primary or revision TKA, pre- and/or postoperatively, and used patch testing to identify Nickel hypersensitivity. Prevalence of Nickel hypersensitivity ranged from 0% to 87.5%. One study compared the prevalence of Nickel hypersensitivity in the same patient group before and after surgery and noted newly positive patch test reactions in three patients (4.2%). Three studies reported lower prevalence of Nickel hypersensitivity in postoperative patients compared to preoperative ones. Seven studies suggested that hypersensitivity might cause adverse clinical outcomes, but six did not support any relationship. Seven studies recommended preoperative patch testing in patients with history of metal allergy, and nine concluded that testing may be valuable postoperatively.

Conclusions

Patients undergoing TKA with no prior history of metal hypersensitivity do not seem to be at an increased risk of developing Nickel hypersensitivity, and there is conflicting evidence that patients with pre-existing hypersensitivity are more likely to experience adverse outcomes. Patch testing remains the most commonly used method for diagnosing hypersensitivity, and evidence suggests preoperative testing in patients with history of metal allergy to aid prosthesis selection, and postoperatively in patients with suspected hypersensitivity once common causes of implant failure have been excluded, since revision with hypoallergenic implants may alleviate symptoms.

Screening and evaluation of lactic acid bacteria with probiotic potential from local Holstein raw milk

There are massive bacteria in the raw milk, especially the lactic acid bacteria (LABs), which have been considered probiotics in humans and animals for a long time. Novel probiotics are still urgently needed because of the rapid development of the probiotic industry. To obtain new LABs with high probiotic potential, we obtained 26 LAB isolates, named L1 ~ L26, from local Holstein raw milk collected from a farm whose milk had never been used for LAB isolation. We identified them at the species level by biochemical and 16S rDNA sequencing methods. Their antagonistic activities against four target pathogens (Escherichia coli ATCC 25922, Staphylococcus aureus ATCC 25923, Pseudomonas aeruginosa PAO1, and Salmonella enterica H9812), co-aggregative ability with these target pathogens, survivability in the simulated gastrointestinal tract conditions and phenol, auto-aggregation and hydrophobicity, hemolytic activity, and antibiotic susceptibility, were evaluated in vitro. Five Lactiplantibacillus plantarum isolates (L5, L14, L17, L19, and L20) showed more promising probiotic potential than others. Specifically, these five isolates conglutinated with and inhibited all the target pathogens, and survived in the simulated gastric juice (92.55 ~ 99.69%), intestinal juice (76.18 ~ 83.39%), and 0.4% phenol (76.95 ~ 88.91%); possessed considerable auto-aggregation (83.91 ~ 90.33% at 24 h) and hydrophobicity (79.32 ~ 92.70%); and were non-hemolytic, sensitive to kinds of common antimicrobials. Our findings demonstrated that these five isolates could be preliminarily determined as probiotic candidates because they have better probiotic potential than those previously reported. Again, this study highlighted the potential of raw milk for probiotic isolating and screening and provided the probiotic industry with five new LAB candidates.

Nano-Selenium Alleviates Cadmium-Induced Acute Hepatic Toxicity by Decreasing Oxidative Stress and Activating the Nrf2 Pathway in Male Kunming Mice

Cadmium (Cd) is known as a highly toxic heavy metal and has been reported to induce hepatotoxicity in animals. Nano-selenium (NSe) is an antioxidant that plays many biological roles such as oxidative stress alleviation. The purpose of this study is to explore the mechanism of action by which NSe inhibits Cd-induced hepatic toxicity and oxidative stress. Sixty eight-week-old male Kunming mice were randomly divided into four groups (15 mice per group). The control group and cadmium groups received distilled water, whereas the sodium-selenite group received 0.2 mg/kg SSe and the NSe group received 0.2 mg/kg NSe intragastrically for 2 weeks. On the last day, all the other groups were treated with Cd (126 mg/kg) except for the control group. The results obtained in this study showed that NSe alleviated Cd-induced hepatic pathological changes. Furthermore, NSe reduced the activities of ALT and AST as well as the content of MDA, while elevated the activities of T-AOC, T-SOD and GSH (P < 0.05). In addition, the NSe group significantly increased mRNA expressions of Nrf2 pathway related molecules (Nrf2, HO-1, NQO-1, GST, GSH-Px, CAT and SOD) compared to the Cd group (P < 0.05). In conclusion, NSe shows its potentiality to reduce Cd-induced liver injury by inhibiting oxidative stress and activating the Nrf2 pathway.

P12 Sustainability: staff knowledge of which items of waste can be recycled in the orthopaedic operating theatre

Introduction

NHS England generates over 20 million tonnes of CO2 per year, representing 4% of the nation's greenhouse gas emissions. One third of all hospital waste comes from operating theatres. Our aim was to investigate the degree of knowledge of sustainable waste segregation amongst theatre staff in an elective orthopaedic centre and identify ways to improve their waste segregation practice.

Methods

Over a one-week period, 20 randomly selected theatre staff of different roles, completed a questionnaire asking them which disposal bin 11 commonly used orthopaedic theatre items should be placed in – general waste or recycling. After initial data collection, posters specifically identifying recyclable items were created and displayed in each operating theatre. Following this intervention, data was re-collected from another 20 randomly selected theatre staff using the same questionnaire.

Results

Results from the initial questionnaire showed general waste and recyclable items were correctly identified by staff in 65% (78/120 responses) and 59% (59/100 responses), respectively. Following the educational intervention, the percentage of correct responses increased to 68.3% (82/120 responses) and 85% (85/100 responses); i.e. staff knowledge of what can go into a recycling bin improved by 36%.

Conclusion

Educating staff by placing posters in the operating theatre can improve knowledge of what orthopaedic theatre items can be recycled and is a simple and effective way of producing sustainable change in surgery. Guiding and empowering individuals to exercise sustainable practice in the operating theatre will help the NHS to overcome the significant challenge of achieving net zero carbon by 2045.

Take-home message

Educating staff by placing posters in the operating theatre is a simple and effective way of improving waste segregation practice and will help the health service to overcome the significant challenge of achieving net zero carbon.

Occurrence, genetic diversity and zoonotic potential of Blastocystis sp. in forest musk deer (Moschus berezovskii) in Southwest China

Blastocystis sp. is a common anaerobic protist with controversial pathogenicity that can infect various animals and humans. However, there are no reports of Blastocystis sp. infections in forest musk deer (Moschus berezovskii). The present study was designed to examine the occurrence, subtype distribution and genetic characterization of Blastocystis sp. in forest musk deer in southwestern China, and to assess the potential for zoonotic transmission. A total of 504 fresh stool samples were collected from captive forest musk deer in four distinct areas of southwestern China. Overall, 14.7% of the forest musk deer (74/504) were found to be infected with Blastocystis sp. The highest occurrence of Blastocystis sp. was observed in Dujiangyan (27.5%), followed by Maerkang (23.3%). The occurrence of Blastocystis sp. was 7.9% and 4.1% in Shimian and Hanyuan, respectively. Significant differences in the occurrence of Blastocystis sp. among different areas were observed (p < 0.05), while we did not observe significant differences among animals of different age and sex (p > 0.05). Two known zoonotic subtypes (ST1 and ST5) and three animal-predominant subtypes (ST10, ST13, and ST14) were identified, of which ST10 was the most common (36/74, 48.6%). Our findings highlight that forest musk deer may be potential reservoirs of zoonotic human Blastocystis sp. infections.

Nanocarriers for combating biofilms: advantages and challenges

Bacterial biofilms are highly resistant to antibiotics and pose a great threat to human and animal health. The control and removal of bacterial biofilms have become an important topic in the field of bacterial infectious diseases. Nanocarriers show great anti-biofilm potential because of their small particle size and strong permeability. In this review, the advantages of nanocarriers for combating biofilms are analyzed. Nanocarriers can act on all stages of bacterial biofilm formation and diffusion. They can improve the scavenging effect of biofilm by targeting biofilm, destroying extracellular polymeric substances, and enhancing the biofilm permeability of antimicrobial substances. Nanocarriers can also improve the antibacterial ability of antimicrobial drugs against bacteria in biofilm by protecting the loaded drugs and controlling the release of antimicrobial substances. Additionally, we emphasize the challenges faced in using nanocarrier formulations and translating them from a preclinical level to the clinical setting.

Preparation of shikonin liposome and evaluation of its in vitro antibacterial and in vivo infected wound healing activity

BACKGROUND

The emergence of antibiotic resistance over the past decade has made the treatment of Staphylococcus aureus infection difficult. Burn wounds infected with methicillin-resistant S. aureus (MRSA) can cause mortality in animals. Shikonin (SH) has been reported to possess antimicrobial and anti-inflammatory properties, and is also responsible for the process of wound healing. However, the pharmacological mechanism of its wound healing process remains poorly comprehended, hence the probable mechanism deserves further investigation.

PURPOSE

The current study was designed to develop a novel SH-liposome with improved anti-MRSA effect and to detect its beneficial wound healing effects.

STUDY DESIGN

In vitro antibacterial tests and in vivo infected wound healing test were conducted.

METHODS

SH-liposome was produced by the film formation method, and the characteristics were measured using a laser particle size analyzer, transmission electron microscopy, and the dialysis method. Additionally, in vitro antibacterial tests were conducted to investigate the antibacterial effects and the relative mechanism of SH-liposome. Furthermore, the therapeutic effects and bioactivity of SH-liposome in MRSA infected burn wounds were investigated in rats. Sixty-four male Sprague Dawley rats (250 ± 10 g) were randomly divided into four groups, including Group I (control group); Group II (model group); Group III (SH-liposome group) and Group IV (Arnebia oil® group), and the drug treatments were applied topically twice daily for 21 days. Further, full thickness skin biopsies at different periods were collected aseptically to evaluate tissue cytokines, recognize flora, observe histopathological changes, and determine the mechanism underlying the wound healing effects of SH-liposome. The data were analyzed via one-way analysis of variance (ANOVA) and Duncan's multiple range test.

RESULTS

The results showed that SH-liposome was successful with a drug load of 4.6 ± 0.17%. Moreover, SH-liposome showed a sustained-release behavior and improved antibacterial ability in a dose-dependent manner. For the possible antibacterial mechanism, we observed that SH-liposome achieved antibacterial activity by damaging the integrity of bacterial cell wall and membrane to further disturb the physiological activities of S. aureus. In addition, SH-liposome facilitated wound healing by inhibiting bacterial activities to control infection, regulating the I-κBα/NFκB-p65 pathway to alleviate inflammation, and directly promoting repair in burn wounds.

CONCLUSION

In conclusion, SH-liposome showed an antibacterial effect against S. aureus, promoted effective healing of infected burn wounds; hence, it could be used as an alternative therapy for drug-resistant infections.

225 First Contact: A Series of Zoom-Based, Virtual on Call Shifts

Aim

COVID-19 has resulted in reduced exposure to on-call shifts where medical students could increase confidence and proficiency in task prioritisation and decision making. Existing ‘simulated on-calls’ provide a substitute in a controlled environment, however in person teaching has also been limited by COVID-19. Our virtual on-call sessions use ZOOM to replicate the higher-level learning experiences normally conferred by live simulation.

Method

We designed a series of virtual ‘on-calls’ for medical students. Participants were ‘on-call’, receiving ‘bleeps’ which were ‘answered’ by calling a facilitator via ZOOM. The facilitator would roleplay a scenario and the ‘Electronic Patient Record’ (EPR) on Google Forms contained patient notes and observations. Students needed to collect information from the facilitator and document a management plan into the EPR. Participants received ‘bleeps’ of varying complexity, urgency and relevance and were expected to prioritise and triage tasks accordingly. Evaluation was via a pre/post session quiz with separate feedback forms.

Results

23 students from 18 universities participated. Students reported increased confidence in managing on-call scenarios, and average scores improved in the post session quiz. Positive feedback was paid to the variety of scenarios, the EPR system and the feeling of realism elicited from the need to triage and prioritise jobs.

Conclusions

Our framework uses readily accessible technology to provide interactive learning experience. Feedback suggested students engaged in higher order learning and thinking, achieving our stated aims. We aim to incorporate technologies such as automation software which will allow for a scalable, free, and accessible virtual on call.

Association of prenatal renal ultrasound abnormalities with pathogenic copy number variants in a large Chinese cohort

OBJECTIVES

To assess the clinical utility of prenatal chromosomal microarray analysis (CMA) in fetuses with abnormal renal sonographic findings, and to evaluate the association of pathogenic or likely pathogenic copy number variants (P/LP CNVs) with different types of renal abnormality.

METHODS

This was a retrospective study of fetuses at 14-36 weeks screened routinely for renal and other structural abnormalities at the Maternal and Child Health Hospital of Guangxi Zhuang Autonomous Region. We retrieved and analyzed data from fetuses with abnormal renal sonographic findings, examined between January 2013 and November 2019, which underwent CMA analysis using tissue obtained from chorionic villus sampling (CVS), amniocentesis or cordocentesis. We evaluated the CMA findings according to type of renal ultrasound anomaly and according to whether renal anomalies were isolated or non-isolated.

RESULTS

Ten types of renal anomaly were reported on prenatal ultrasound screening, at a mean ± SD gestational age of 24.9 ± 4.8 weeks. The anomalies were diagnosed relatively late in this series, as 64% of cases with an isolated renal anomaly underwent cordocentesis rather than CVS. Fetal pyelectasis was the most common renal ultrasound finding, affecting around one-third (34.32%, 301/877) of fetuses with a renal anomaly, but only 3.65% (n = 11) of these harbored a P/LP CNV (comprising: isolated cases, 2.37% (4/169); non-isolated cases, 5.30% (7/132)). Hyperechogenic kidney was found in 5.47% (n = 48) of fetuses with a renal anomaly, of which 39.58% (n = 19) had a P/LP CNV finding (comprising: isolated cases, 44.44% (16/36); non-isolated cases, 25.00% (3/12)), the highest diagnostic yield among the different types of renal anomaly. Renal agenesis, which accounted for 9.92% (n = 87) of all abnormal renal cases, had a CMA diagnostic yield of 12.64% (n = 11) (comprising: isolated cases, 11.54% (9/78); non-isolated cases, 22.22% (2/9); unilateral cases, 11.39% (9/79); bilateral cases, 25.00% (2/8)), while multicystic dysplastic kidney (n = 110), renal cyst (n = 34), renal dysplasia (n = 27), crossed fused renal ectopia (n = 31), hydronephrosis (n = 98), renal duplication (n = 42) and ectopic kidney (n = 99) had overall diagnostic rates of 11.82%, 11.76%, 7.41%, 6.45%, 6.12%, 4.76% and 3.03%, respectively. Compared with the combined group of CMA-negative fetuses with any other type of renal anomaly, the rate of infant being alive and well at birth was significantly higher in CMA-negative fetuses with isolated fetal pyelectasis or ectopic kidney, whereas the rate was significantly lower in fetuses with isolated renal agenesis, multicystic dysplastic kidney or severe hydronephrosis. The most common pathogenic CNV was 17q12 deletion, which accounted for 30.14% (22/73) of all positive CMA findings, with a rate of 2.51% (22/877) among fetuses with an abnormal renal finding. Fetuses with 17q12 deletion exhibited a wide range of renal phenotypes. Other P/LP CNVs in the recurrent region that were associated with prenatal renal ultrasound abnormalities included 22q11.2, Xp21.1, Xp22.3, 2q13, 16p11.2 and 1q21, which, collectively, accounted for 2.17% (19/877) of the fetuses with prenatal renal anomalies.

CONCLUSIONS

In this retrospective review of CMA findings in a large cohort of fetuses with different types of renal ultrasound abnormality, the P/LP CNV detection rate varied significantly (3.03-39.58%) among the different types of kidney anomaly. Our data may help in the decision regarding whether to perform prenatal genetic testing in fetuses with renal ultrasound findings. Specifically, prenatal CMA testing should be performed in cases of hyperechogenic kidney, regardless of whether or not the anomaly is isolated, while it should be performed postnatally rather than prenatally in cases of fetal pyelectasis. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.

Plant functional traits shape growth rate for xerophytic shrubs

Trade-offs exist for xerophytic shrubs between functional traits, involving in water loss and assimilate accumulation, can contribute to its survival and growth rate regulation in arid environments. However, growth analysis based on plant functional traits has been focused on the study of herbs and woody species. It is still unclear how the functional traits of xerophytic shrubs regulate their growth rate. In this study, we selectedeight xerophytic shrubs as samples to analyze the regulation process of the functional traits of shrubs on growth rate. Plants were cultivated for three years, and three harvests (every one year) were carried out. Factors explaining between-species differences in relative growth rate (RGR) varied, depending on whether different ages were considered. The results showed that RGR was positively correlated with net assimilation rate, but there was a significant negative correlation with leaf area ration (LAR), specific leaf area (SLA), and leaf biomass ratio in the age 1. However, in the age 2, RGR showed a significant positive correlation with the morphological traits (i.e., leaf area ration and specific leaf area), but not with physiological traits (i.e., net assimilation rate) and leaf biomass allocation. Our results suggested that the fluctuation of environmental factors affects the regulation path of the plant functional traits on RGR of xerophytic shrubs. However, the analysis of causality model showed that no matter in which age, net assimilation rate and leaf area ration principally drive the variation in RGR among xerophytic shrubs.

Aristolochic Acid I-Induced Hepatotoxicity in Tianfu Broilers Is Associated with Oxidative-Stress-Mediated Apoptosis and Mitochondrial Damage

Simple Summary

Aristolochic acid (AA) is a component of traditional Chinese herbs and commonly used in the farm poultry industry in China for anti-infection, anti-viral and anti-bacterial treatment. However, long-term and over-exposure of these drugs has been proven to be associated with serious hepatotoxicity, but the mechanism of AA-I-induced hepatotoxicity remains unknown. Therefore, in this study, a subchronic toxicity test was conducted to evaluate the mechanism of AA-I-induced hepatotoxicity in Tianfu broilers. Subchronic exposure to high doses of AA-I in broilers can cause serious hepatotoxicity by breaking the redox balance to form oxidative stress, along with promoting oxidative-stress-mediated apoptosis and mitochondrial damage. In conclusion, AA-I has been found to damage broilers’ livers in high doses. This study provides suggestions for the clinical application of traditional Chinese medicine containing AA-I in the poultry industry.

Abstract

Aristolochic acid (AA) is a component of traditional Chinese herbs and commonly used for farm animals in China. Over-exposure of AA has been proven to be associated with hepatotoxicity; however, the mechanism of action of AA-I-induced hepatotoxicity remains unknown. In the current study, a subchronic toxicity test was conducted to evaluate the mechanism of AA-induced hepatotoxicity in Tianfu broilers. According to the results, AA-I-induced hepatotoxicity in Tianfu broilers was evidenced by the elevation of liver weight, levels of serum glutamic oxalacetic transaminase (GOT) and glutamic-pyruvic transaminase (GPT). Furthermore, hepatocyte swelling, vesicular degeneration and steatosis were observed. Additionally, AA-I elevated the production of reactive oxygen species (ROS) and induced oxidative stress, which further led to excessive apoptosis, characterized by mitochondrial depolarization, upregulation of Bax, and down-regulation of Bcl-2 expression. In conclusion, the mechanism of AA-I-induced hepatotoxicity was associated with oxidative-stress-mediated apoptosis and mitochondrial damage.

Prevalence and characterization of antibiotic resistance genes and integrons in Escherichia coli isolates from captive non-human primates of 13 zoos in China

Antimicrobial resistance (AMR) has become a public health concern; but antibiotic resistance genes (ARGs) and integrons that link to AMR of Escherichia coli from non-human primates remain largely unknown. This study aimed to investigate antibiotic resistance, emerging environmental pollutants ARGs, and integrons factors (intI1, intI2 and intI3) in 995 E. coli isolates obtained from 50 species of captive non-human primates of 13 zoos in China. Our result showed 83.62% of the E. coli isolates were resistant to at least one antibiotic and 47.94% isolates showed multiple drug resistances (MDR). The E. coli isolates mainly showed resistance to tetracycline (tetracycline 62.71%, doxycycline 61.11%), β-lactams (ampicillin 54.27%, amoxicillin 52.36%), and sulfonamide (trimethoprim-sulfamethoxazole 36.78%). A total of 423 antibiotic resistance patterns were observed, of which DOX/TET (49 isolates, 4.92%) was the most common pattern. Antibiotic resistance rates among 13 zoos had a significant difference (P < 0.01). We further detected 22 ARGs in the 995 E. coli isolates, of which tetA had the highest occurrence (70.55%). The presence of integrons class 1 and 2 were 24.22% and 1.71%, respectively, while no class 3 integron was found. Significant positive associations were observed among integrons and antibiotics, of which the strongest association was observed for integrons / Gentamicin (OR, 2.642) and integrons / Cefotaxime (OR, 2.512). In addition, cassette arrays were detected in 64 strains of class 1 integron-positive isolates (26.56%) and 10 strains of class 2 integron-positive isolates (58.82%). Eighteen cassette arrays were found within 64 class 1 integron isolates, while 3 cassette arrays were identified within 10 class 2 integron isolates. Our results indicate a high diversity of antibiotic resistance phenotypes in non-human primate E. coli isolates, which carry multiple ARGs and integrons. Corresponding preventive measures should be taken to prevent the spread of integron-mediated ARGs in non-human primates and their living environments in zoos.

Total knee arthroplasty is safe for patients aged ≥80 years in Hong Kong

INTRODUCTION

Total knee arthroplasty (TKA) is an efficacious operation that improves pain and function in patients with knee arthritis. Because of the population ageing trend in Hong Kong, there is a need to determine the safety profile of TKA in older patients. This study examined the age of patients who underwent TKA in the past 10 years in Hong Kong; the aim was to investigate the mortality safety profile and clinical outcomes of TKA in patients aged ≥80 years.

METHODS

This study included all patients who underwent primary TKA in the Hospital Authority (HA) from 2010 to 2019. Incidences of 30-day, 90-day, and 1-year mortality were established. Clinical outcomes of patients aged ≥80 years in one cluster of HA hospitals were assessed.

RESULTS

Between 2010 and 2019, 25 040 TKA procedures were conducted in all HA hospitals; 2491 were conducted in patients aged ≥80 years. The median age at operation was higher during 2015-2019 than during 2010-2014 (70 vs 69 years; P<0.001); furthermore, an increase was observed in the proportion of patients aged ≥80 years at the time of operation. Incidences of 30-day, 90-day, and 1-year mortality were 0.156%, 0.35%, and 1.09%, respectively.

CONCLUSIONS

In this first study to examine the safety profile of TKA in older patients in Hong Kong, the mean age at the time of TKA and proportion of patients aged ≥80 years have steadily risen in the past decade. Even in older patients, TKA is a reasonably safe procedure.

Chitosan-poloxamer-based thermosensitive hydrogels containing zinc gluconate/recombinant human epidermal growth factor benefit for antibacterial and wound healing

Chitosan/poloxamer-based thermosensitive hydrogels containing zinc gluconate/recombinant human epidermal growth factor (ZnG/rhEGF@Chit/Polo) were developed as a convenient, safe and effective dressing for skin wound treatment. Their fabrication procedure and characterization were reported, and their morphology was examined by a scanning electron microscope. Antibacterial and biofilms activities were evaluated by in vitro tests to reveal the inhibitory effects and scavenging activity on the biofilms of Staphylococcus aureus and Pseudomonas aeruginosa. ZnG/rhEGF@Chit/Polo was also investigated as a potential therapeutic agent for wound healing therapy. In vivo wound healing studies on rats for 21 days proves that ZnG/rhEGF@Chit/Polo supplements the requisite Zn²⁺ and rhEGF for wound healing to promote the vascular remodeling and collagen deposition, facilitate fibrogenesis, and reduce the level of interleukin 6 for wound basement repair, and thus is a good wound therapy.

Genetic characterization and zoonotic potential of Blastocystis from wild animals in Sichuan Wolong National Natural Reserve, Southwest China

Blastocystis is a prevalent eukaryotic parasite that has been identified in a wide range of hosts. Several species are considered potential sources of Blastocystis infection in humans, but little is known about the prevalence of Blastocystis in wild animals. In this study, the prevalence and subtypes of Blastocystis were investigated to assess the zoonotic potential of wild animals in Sichuan Wolong National Natural Reserve. A total of 300 fecal samples were collected from 27 wildlife species in three areas of the Reserve. The subtype (ST), genetic characteristics, and prevalence of Blastocystis were determined by PCR amplification of part (~600 bp) of the SSU rRNA gene. Thirty fecal samples (10.0%) were Blastocystis-positive. The highest prevalence of Blastocystis was found in Yinchanggou (18.3%), with significantly less found in Niutoushan (7.5%) and Genda (5.5%) (p < 0.05). No significant differences were associated with different orders of animals in prevalence, which may be because of the small number of positive samples obtained. Sequence analysis showed five subtypes (ST1, ST3, ST5, ST13, and ST14), with ST13 and ST14 being predominant (33% each), followed by ST1 (20%). This is the first molecular investigation of Blastocystis infection in the wild animals of southwestern China. Subtypes ST1, ST3, ST5, and ST14 have previously been identified in humans, suggesting that wild animals may be potential reservoirs of Blastocystis for humans.

CRYPTOSPORIDIUM SPP. IN PET DWARF WINTER WHITE RUSSIAN HAMSTERS (PHODOPUS SUNGORIS SUNGORIS) IN CHINA

Cryptosporidium spp. have been identified in a wide range of hosts, such as humans and domestic and wild animals, while less information about the prevalence of Cryptosporidium spp. in pet hamsters is documented. A total of 351 dwarf winter white Russian hamsters' fecal specimens were collected from 6 pet markets from the cities of Luzhou and Ziyang in Sichuan province in the southwestern part of China. The prevalence of Cryptosporidium spp. determined with nested-PCR amplification of the partial small-subunit (SSU) rRNA gene was 39.32% (138/351). The highest prevalence of Cryptosporidium spp. was in pet market 5 (79.49%, 62/78), followed by pet market 6 (38.64%, 17/44). The lowest prevalence of Cryptosporidium spp. was observed in pet market 3 (14.89%, 7/47). Statistically significant differences in the prevalence of Cryptosporidium spp. were observed among different pet markets (χ2 = 76.386, df = 5, P < 0.05), and a further post hoc test revealed that only pet market 5 was significantly different from other pet markets. Molecular analysis showed that 4 different Cryptosporidium species or genotypes were identified: Cryptosporidium parvum (n = 127), Cryptosporidium chipmunk genotype III (n = 6), Cryptosporidium andersoni (n = 4), and Cryptosporidium wrairi (n = 1). The identification of Cryptosporidium spp. was further tested with the 60-kDa glycoprotein (GP60) gene, and the positive rate was 29.7% (41/138). This is the first molecular report on Cryptosporidium spp. infection in dwarf winter white Russian hamsters in China. With C. parvum and C. andersoni being identified in both humans and pet hamsters, these findings suggest that pet hamsters may be potential reservoirs of zoonotic Cryptosporidium species and subtypes.

Quantification of peak blood flow velocity at the cardiac valve and great thoracic vessels by four-dimensional flow and two-dimensional phase-contrast MRI compared with echocardiography: a systematic review and meta-analysis

AIM

To objectively examine the agreement and correlation between four-dimensional (4D) flow magnetic resonance imaging (MRI) and traditional two-dimensional (2D) phase-contrast (PC) MRI with the reference standard of Doppler echocardiography for measuring peak blood velocity at the cardiac valve and great arteries, and to assess if 4D flow MRI offers an advantage over the traditional 2D method.

MATERIALS AND METHODS

The literature was searched systematically for studies that evaluate the degree of correlation and agreement between 4D flow MRI or 2D PC MRI and Doppler retrieved from PubMed, EMBASE, and the Cochrane Library. A meta-analysis was conducted to determine the peak velocity pooled bias with 95% limits of agreement (LoA) and correlation coefficient (r) for 4D flow MRI and 2D PC MRI compared with Doppler.

RESULTS

Ten studies that compared 4D flow MRI with Doppler and 12 studies that compared 2D PC MRI with Doppler were included. 4D flow MRI showed an underestimation with bias and 95% LoA of -0.09 (-0.41, 0.24) m/s (p=0.079) while 2D PC MRI showed a poorer agreement with a bias and 95% LoA of -0.25 (-0.53, 0.03), p=0.596. 4D flow MRI and 2D PC MRI showed a strong correlation with R=0.80 (95% CI 0.75, 0.84; p<0.001) and R=0.83 (95% CI 0.79, 0.87; p<0.001), respectively.

CONCLUSION

In this meta-analysis, 4D flow MRI provides improved assessment of peak velocity when compared with traditional 2D PC MRI. 4D flow MRI can be considered an important complement or substitute to Doppler echocardiography for peak velocity assessment.

A new antisarcoma strategy: multisubtype heat shock protein/peptide immunotherapy combined with PD-L1 immunological checkpoint inhibitors

Osteosarcoma, a common malignant tumor in orthopedics, often has a very poor prognosis after lung metastasis. Immunotherapy has not achieved much progress in the treatment because of the characteristics of solid tumors and immune environment of osteosarcoma. The tumor environment is rather essential for sarcoma treatment. Our previous study demonstrated that heat shock proteins could be used as antitumor vaccines by carrying tumor antigen peptides, and we hypothesize that an anti-osteosarcoma effect may be increased with an immune check point inhibitor (PD-L1 inhibitor) as a combination treatment strategy. The present study prepared a multisubtype mixed heat shock protein osteosarcoma vaccine (mHSP/peptide vaccine) and concluded that the mHSP/peptide vaccine was more effective than a single subtype heat shock protein, like Grp94. Therefore, we used the mHSP/peptide vaccine in combination with a PD-L1 inhibitor to treat osteosarcoma, and the deterioration of osteosarcoma was effectively hampered. The mechanism of combined therapy was investigated, and AKT expression participates with sarcoma lung metastasis. This study proposed an antisarcoma strategy via stimulation of the immune system as a further alternative approach for sarcoma treatment and elucidated the mechanism of combined therapy.

Prevalence and Molecular Characterization of Cryptosporidium serpentis in Captive Snakes in China

Cryptosporidium species are the causative agent of cryptosporidiosis and common intracellular parasites that can infect a wide range of vertebrates, including snakes. In previous studies, Cryptosporidium species infections have been reported in snakes in Asia, Europe, and North America. However, limited information is available about the prevalence and molecular characterization of Cryptosporidium in captive snakes in China. Fecal specimens from 609 captive snakes were collected from Beijing (n = 227), Chengdu (n = 12), Dazhou (n = 359), and Ziyang (n = 11). The partial small-subunit (SSU) rRNA gene was amplified by nested polymerase chain reaction to determine the prevalence of Cryptosporidium, and a phylogenetic tree was constructed to assess evolutionary relationships and genetic characteristics. The overall prevalence of Cryptosporidium was 1.97% (12/609). BLAST and phylogenetic analysis of the small subunit ribosomal RNA (SSU rRNA) gene showed that the parasites belonged to Cryptosporidium serpentis. To the best of our knowledge, this is the first study to report the prevalence of Cryptosporidium in snakes of southwestern and northern China and provides preliminary data for the control and prevention of cryptosporidiosis in the investigated areas.

RNA-binding protein Hfq plays a vital role in cellulose decomposition throughout affecting cellulase gene expression

OBJECTIVE

To study the function of the RNA-binding protein Hfq in Bacillus subtilis cellulose decomposition.

RESULTS

In the medium with sodium carboxymethylcellulose (Na-CMC) as the sole carbon source, the knockout of Hfq resulted in a 38.0% ± 2.1% and 76.6% ± 7.1% decrease in cellulose hydrolysis ability and cellulase activity, respectively. The results of real-time quantitative PCR revealed that several cellulase genes (eglS, bglA, and bglC) were significantly downregulated in the Hfq knockout strain. The isogenic Δhfq complemented strain recovered the cellulose hydrolysis ability, cellulase activity, and expression level of cellulase genes. In addition, the survival of Hfq mutant in stationary phase was significantly affected.

CONCLUSION

RNA-binding protein Hfq is involved in the regulation of cellulose hydrolysis ability, cellulase activity, cellulase gene expression, and stationary phase survival.