Rapid and ultrasensitive detection of pathogen-associated biomarkers is vital for the early diagnosis and therapy of bacterial infections. Herein, we developed a close-packed and ordered Au@AgPt array coupled with a cascade triggering strategy for surface-enhanced Raman scattering (SERS) and colorimetric identification of the Staphylococcus aureus biomarker micrococcal nuclease (MNase) in serum samples. The trimetallic Au@AgPt nanozymes can catalyze the oxidation of 3,3',5,5'-tetramethylbenzidine (TMB) molecules to SERS-enhanced oxidized TMB (oxTMB), accompanied by the color change from colorless to blue. In the presence of S. aureus, the secreted MNase preferentially cut the nucleobase AT-rich regions of DNA sequences on magnetic beads (MBs) to release alkaline phosphatase (ALP), which subsequently mediated the oxTMB reduction for inducing the colorimetric/SERS signal fade away. Using this "on-to-off" triggering strategy, the target S. aureus can be recorded in a wide linear range with a limit of detection of 38 CFU/mL in the colorimetric mode and 6 CFU/mL in the SERS mode. Meanwhile, the MNase-mediated strategy characterized by high specificity and sensitivity successfully discriminated between patients with sepsis (n = 7) and healthy participants (n = 3), as well as monitored the prognostic progression of the disease (n = 2). Overall, benefiting from highly active and dense "hot spot" substrate, MNase-mediated cascade response strategy, and colorimetric/SERS dual-signal output, this methodology will offer a promising avenue for the early diagnosis of S. aureus infection.

Objective:To analyze the clinical characteristics of dengue fever patients, summarize the course and characteristics of the disease, and analyze the risk factors that affect the condition.Methods:Retrospective collection of general information, clinical symptoms, medical history, laboratory tests, prognosis and other clinical data of dengue fever patients that admitted to Jinghong First People's Hospital and severe dengue fever patients at People's Hospital of Xishuangbanna Dai Autonomous Prefecture from June to December 2023 was conducted using a case report form (CRF). According to the diagnostic criteria of the World Health Organization (WHO), patients were divided into dengue fever group, dengue fever with warning signs group, and severe dengue fever group. The differences in clinical data between different groups of patients were analyzed and compared. Binary multiple factor Logistic regression analysis was used to explore the risk factors affecting the severity of dengue fever in patients. Receiver operator characteristic curve (ROC curve) was drawn to analyze the predictive value of prediction models constructed for various risk factors for severe dengue fever. Subgroup analysis was performed on the prognosis of severe dengue fever patients, and the differences in clinical data between two groups of patients with different prognoses were compared. Binary multivariate Logistic regression analysis was used to explore the risk factors affecting the prognosis of severe dengue fever patients. ROC curve was drawn to analyze the predictive value of prediction models constructed for various risk factors on the prognosis of severe dengue fever patients.Results:A total of 2 264 patients were included, including 499 cases in the dengue fever group, 1 379 cases in the dengue fever with warning signs group, and 386 in the severe dengue fever group (43 deaths and 343 survivors). The most common symptom of dengue fever patients was fever (94.70%), followed by muscle soreness (70.54%), headache (63.12%), fatigue (58.92%), and chills (46.02%). Compared with the dengue fever group and the dengue fever with warning signs group, the ratio of thalassemia and the levels of cardiac troponin (cTnI, cTnT), MB isoenzyme of creatine kinase (CK-MB), and myoglobin were significantly increased in patients with severe dengue fever group, albumin (Alb) was significantly decreased in patients with severe dengue fever group. The levels of cTnT and myoglobin in patients with dengue fever with warning signs group were significantly higher than those in the dengue fever group, and the level of Alb in patients with dengue fever with warning signs group was significantly lower than that in the dengue fever group, the differences were statistically significant (all P < 0.05). Binary multivariate Logistic regression analysis showed that thalassemia [odds ratio ( OR) = 6.214, 95% confidence interval (95% CI) was 2.337-16.524, P < 0.001], Alb ≤ 36 g/L ( OR = 6.297, 95% CI was 4.270-9.286, P < 0.001), and cTnT levels ( OR = 1.008, 95% CI was 1.002-1.015, P = 0.016) were risk factors for severe dengue fever. ROC curve analysis showed that the area under the ROC curve (AUC) for predicting severe dengue fever based on the prediction models constructed for the above risk factors was 0.856, with the best predictive value of 0.067, sensitivity of 67.1%, and specificity of 99.4%. In the subgroup analysis of patients with severe dengue fever, compared with the survival group, the levels of hematocrit (HCT), cTnT, and CK-MB in the death group patients were significantly increased, while the level of Alb was significantly decreased, and the differences were statistically significant. Binary multivariate Logistic regression analysis showed that Alb ( OR = 0.839, 95% CI was 0.755-0.932, P = 0.001), HCT ( OR = 1.086, 95% CI was 1.010-1.168, P = 0.025), elevated troponin level ( OR = 10.119, 95% CI was 2.596-39.440, P < 0.001), and CK-MB ( OR = 1.081, 95% CI was 1.032-1.133, P < 0.001) were risk factors for mortality in patients with severe dengue fever. ROC curve analysis showed that the AUC for predicting death in severe dengue fever patients based on the prediction models constructed for the above risk factors was 0.881, with the best predictive value of 0.113, sensitivity of 75.0%, and specificity of 88.9%. Conclusion:Thalassemia, Alb≤36 g/L, and cTnT level are risk factors for severe dengue fever, while HCT level, Alb level, CK-MB level, and elevated troponin level are risk factors for death in patients with severe dengue fever.

The management of antibiotic-resistant, bacterial biofilm infections in skin wounds poses an increasingly challenging clinical scenario. Pseudomonas aeruginosa infection is difficult to eradicate because of biofilm formation and antibiotic resistance. In this study, we identified a new benzothiazole derivative compound, SN12 (IC₅₀ = 43.3 nmol/L), demonstrating remarkable biofilm inhibition at nanomolar concentrations in vitro. In further activity assays and mechanistic studies, we formulated an unconventional strategy for combating P. aeruginosa-derived infections by targeting the two-component (Gac/Rsm) system. Furthermore, SN12 slowed the development of ciprofloxacin and tobramycin resistance. By using murine skin wound infection models, we observed that SN12 significantly augmented the antibacterial effects of three widely used antibiotics-tobramycin (100-fold), vancomycin (200-fold), and ciprofloxacin (1000-fold)-compared with single-dose antibiotic treatments for P. aeruginosa infection in vivo. The findings of this study suggest the potential of SN12 as a promising antibacterial synergist, highlighting the effectiveness of targeting the two-component system in treating challenging bacterial biofilm infections in humans.

Objective:To analyze the molecular epidemiological characteristics of Campylobacter fetus subsp. testudinum ( Cft). Methods:Fifteen strains of Cft collected in our laboratory from 2010 to 2022 were subjected to whole-genome sequencing. Their epidemiological characteristics were analyzed based on the global genome data of Cft on GenBank database. MLST-GrapeTree software was used to obtain the genetic structure of Cft strains. A phylogenetic tree was constructed using core-genome single nucleotide polymorphism (cgSNP) analysis, and the sequence clusters were identified using rhierBAPS. Virulence genes and drug resistance genes of Cft strains were annotated using CARD, ResFinder and VFDB database. Their susceptibility to antibiotics was tested using E-test method and the results were analyzed using the CLSI-M45 sensitivity standard for Campylobacter jejuni/ Campylobacter coli. Results:Based on average nucleotide identity (ANI) analysis, the genome data of 41 Cft strains including 24 isolated from human, 13 from animals and four of unknown sources were collected from GenBank database. Among the 24 human-derived strains, 20 were linked to Asian descent and only one was linked to Caucasian descent (spouse of Asian descent), showing statistically significant differences in human ethnicity. All of the 13 animal-derived strains were originated from reptilian sources, including six from turtles, four from snakes and three from lizards. MLST revealed that ST46 was the predominant ST in China, while ST15 was the major sequence type in the United States. Grapetree analysis also demonstrated that the genetic diversity in China was greater than that in the United States. The phylogenetic tree constructed based on cgSNP and BAPS identified six distinct sequence clusters. The Chinese isolates were scattered in diverse sequence clusters and closely related to animal-derived strains, while the American isolates mainly belonged to ST15. The genes encoding virulence factors such as flagella, glycosylation systems and adhesins were carried by all of the 41 Cft strains (100.00%). The invasion-related virulence genes, such as the genes encoding the IV type secretion system ( virB4, virB9, virD4) and the resistance-related tetO efflux pump gene were specifically identified in the emerging ST74 clones. In vitro drug susceptibility testing of 15 Chinese isolates revealed 46.67% of the Cft strains were resistant to ciprofloxacin and 100.00% were sensitive to erythromycin. Conclusions:The global sequence clusters of Cft isolates showed a great genetic diversity. Most of the people with Cft infection had basic immune diseases and might have eaten or had contact with reptiles. Notably, the Chinese domestic infection of ST46 and the emerging ST74 should arouse our more attention.

Objective: Establishing the mass spectrum library of a new Campylobacter- " C.fetus subsp.testudinum" for rapid species identification in clinical microbiology laboratory. Methods: Illumina second generation sequencing platform 2000/miSeq was used to carry out high flux genome sequencing for the strains which were collected to establish mass spectrum library.The analysis oforthologous average nucleotide identity (OrthoANI) between collected strains and reference strains was performed at JAVA 8 operation environment. Then, the mass spectrums ofcollected strains andreference strains were acquired using MALDI-TOF MS. And the mass spectrum library of C. fetus subsp.testudinum. were established and verified. Results: The OrthoANI analysis showed that the OrthoANI value of the collected strains and the reference strain C. fetus subsp.testudinum03-427 was 99.30%-99.96%, while the OrthoANI values of collected strains and C. fetus subsp.venerealisNCTC10354 orC.fetus subsp.fetus82-40 were 91.05%-92.26%. With reference to OrthoANI ≥ 95% as the basis for the determination of the same strain, the strains which collected to establish mass spectrum library was finally identified as " C. fetus subsp.testudinum" . The identification accuracy rate of the mass spectrum library was 100% (consistent with gene sequencing), and the confidence interval was 82.3%-99.9%, identification of the same strain is 100% reproducible. Conclusions The new" gold standard" based on high throughput sequencing and total genome analysis has provided the ideal reference value for the establishment of mass spectrum library.And the accurate and objective reference spectrum of the" C.fetus subsp.testudinum" provides a new platform for the rapid diagnosis of fetal Campylobacter infection. (Chin J Lab Med, 2018, 41: 583-588)

Objective Reference standard of the RPOB(rifampin resistance)gene recommended by CLSI-MM18A(Interpretive Criteria for Identification of Bacteria and Fungi by DNA Target Sequencing) was used to evaluate the ability of MALDI-TOFMS techniques for the identification and classification of non-tuberculous Mycobacterium.Methods Fifty five clinicalstrains were collected from 2012 to 2016 with different sources.The RPOB gene was sequenced, and results were applied to phylogenetics analysis. MALDI-TOF MS technology was implemented to identify the strains, and cluster analysis was conducted based on protein fingerprint.The consistency of two methods for NTM identification and typing was evaluated.Results The RPOB gene method showed a good ability of identification(similarity>99.0%) and subtyping(to subspeciesof the complex level).The French BioMérieux MALDI-TOF MS identified 89.1% of 55 strains to genus level and 78.2% to species level.The phylogeneticsanalysis of protein fingerprint by SARAMS Premium software also showed good typing ability.Conclusions MALDI-TOF MS technology can identify and classify non-tuberculous Mycobacterium effectively,which is rapid and easy.It is complementary to RPOB gene method in laboratory application.

Objective Zika virus disease is an acute infectious disease caused by Zika virus transmitted through Aedes mosquitoes. To explore the therapeutic effect of integrated traditional Chinese and Western Medicine for Zika virus disease, the treatment process of the first imported case in China was reviewed. Methods The first imported Zika virus disease in China was admitted to Ganxian People's Hospital in Jiangxi Province on February 6th, 2016, and the patient received isolation treatment for 9 days and cured later. The effect of antiviral treatments including Xiyanping injection was evaluated based on clinical diagnosis and treatment process of the patient. Results A 34-year old male patient was admitted with chief complaint of fever for 9 days, orbital pain and itching rash for 4 days on February 6th, 2016. ① Epidemiological characteristics: the patient was bitted by mosquitoes during his business trip in Venezuela since January 1st, where Zika virus disease was spreading. On January 20th he had dizziness without fever, and the symptom disappeared after taking medicines without details. Paroxysmal dizziness, chills and mild fever without myalgia was experienced on January 28th. On February 3rd small red rash appeared in the neck, spreading to anterior part of chest, limbs and trunk, and the fever, fatigue, nausea was continued, and a new symptom of paroxysmal pain in back of ears and orbits appeared, during which he had not go to hospital. The symptoms relieved on February 4th. He returned to Ganxian County on February 5th, he had yellow stool 3 times with normal temperature, without abdominal pain, and red rash still appeared in the neck. He went to Ganxian People's Hospital on February 6th, 2016. ② Clinical manifestation: the vital signs showed a temperature of 36.8 ℃, a pulse rate of 80 bpm, a respiratory rate of 20 bpm, and a blood pressure of 110/70 mmHg (1 mmHg = 0.133 kPa). It was showed by physical examination that red rash appeared in the neck, and no superficial enlarged lymph nodes were found. Bilateral conjunctival congestion was obvious, physiological reflex existed and pathological reflex was not found. ③ Auxiliary lab test and examination: no abnormal finding were revealed throughout examination and laboratory tests, including routine blood test, liver function, renal function, serum myocardial enzyme, electrolyte, blood sugar, C-reactive protein (CRP), troponin I (TnI), and procalcitonin (PCT), except slight prolongation in activated partial thromboplastin time (APTT, 38.6 s) on February 6th; and slightly dense shadow in left lung in lung CT scan, considering inflammatory changes and slight emphysema (especially in the left lower lung) as well as bilateral renal calculus on February 8th. No significant abnormalities were found in electrocardiogram and B ultrasound test of liver, spleen, and pancreas. ④ Virus confirmation: Zika virus nucleic acid was positive reported by Jiangxi Province Center for Disease Control and Prevention (CDC) on February 7th and Chinese CDC on February 9th, respectively, though Dengue virus were negative reported by Ganzhou CDC on February 6th. Right after the first diagnosis, anyone who had been in close contact with the patient received medical monitoring. ⑤Treatment process: on February 6th, symptomatic treatment was prescribed since admitted into the infectious isolation wards and daily intravenous drip of Xiyanping injection 250 mg was prescribed for antiviral therapy. On February 7th, the patient had no fever, with occasional chills, neck rash was disappeared, orbital pain relieved and bilateral conjunctival hyperemia range was paler and narrowed, and his condition improved. Ibuprofen was administered for defervesce 3 times a day when his temperature reached to 37.5 ℃ at 16:00. On February 8th, the patient had no fever, times of chills was significantly reduced, without myalgia and rash, orbital pain and conjunctival hyperemia further recovered. On February 9th, bilateral eyes slightly tingling, mild conjunctival congestion, no fever chills or other discomfort was found. The chloramphenicol eye drops was prescribed for relieving sting pain with conjunctival congestion twice a day as recombinant human interferon alpha eye drops was out of store. The patient was comfortable from February 11th to February 13th. Blood and urine test for Zika were reported negative by the Chinese CDC and Jiangxi Province CDC. Because all the discharge criteria were satisfied, the patient was discharged on February 14th. Conclusions At present, there is no specific effective drug to prevent and treat Zika virus disease effectually. After receiving symptomatic treatment and antiviral treatments including Xiyanping injection, the patient's symptoms were relieved. Zika virus nucleic acid in blood and urine was negative. The patient was discharged. Combination of traditional Chinese medicine and Western medicine maybe a good method to prevent and treat Zika virus disease.

To established an effective GC-MS /MS method for the contents determination of the residual DEHP in injection equipment, and investigate the effect of the pretreatment on the measurement. To simulate the clinical conditions of use, under the condition of 37 degrees C balance extraction, extract liquor by chloroform extraction, then the extract followed by analysis of GC-MS /MS. The method was simple, rapid, sensitive and accurate. The limits of quantitation (LOQ, S/N = 5) of cyclohexanone was 0.075 μg/mL, The spiked average recoveries ranged from 92% to 98%. The relative standard deviations (RSDs) of the method ranged from 1.01% to 1.61%, The method was simple, fast, sensitive and accurate, and may serve as a mass control method for residual DEHP in injection equipment.
Cyclohexanones ; chemistry ; Diethylhexyl Phthalate ; chemistry ; Equipment Contamination ; Gas Chromatography-Mass Spectrometry ; Injections ; instrumentation ; Limit of Detection ; Plasticizers ; chemistry

Objective To study the anti-fatigue effect of methylphenidate hydrochloride oral fast dissolving films (MPH-OFDF) and its mechanism .Methods 60 mice were randomly divided into 6 groups as:normal control group (physiological sa-line) ,model group (physiological saline) ,Yiqiyangxue oral liquids positive group (7 .00 mg/kg) ,MPH-OFDF high-dose group (5 .20 mg/kg) ,MPH-OFDF middle-dose group (2 .60 mg/kg) and MPH-OFDF low-dose group (1 .30 mg/kg) .Besides the normal control group ,model group and positive group were orally administered ,the other groups are administered with the drug once daily sublingually daily for consecutive 15 days .The mice were put in the load-weighted swimming test 30 min after the last oral administration ,then the anti-fatigue effect was assessed based on recording exhausting swimming time and detec-ting the levels of serum lactale dehydrogenase (LDH) ,creatine kinase (CK) ,triglycerides (TG) in mice .Results Compared with control group ,the middle-dose and the high-dose MPH could prolong the exhausting swimming time (P<0 .05 ,P<0 .01) and decrease the activity of LDH and CK significantly (P<0 .05 ,P<0 .01);in addition the middle-dose MPH could decrease the content of TG (P<0 .05) .Conclusion The MPH had marked anti-fatigue effect that may be associated with reduced ser-um LDH ,CK and TG .

To established an effective GC-MS /MS method for the contents determination of the residual DEHP in injection equipment, and investigate the effect of the pretreatment on the measurement. To simulate the clinical conditions of use, under the condition of 37oC balance extraction, extract liquor by chloroform extraction, then the extract folowed by analysis of GC-MS /MS. The method was simple, rapid, sensitive and accurate. The limits of quantitation( LOQ, S/N = 5) of cyclohexanone was 0.075mg/mL, The spiked average recoveries ranged from 92% to 98%.The relative standard deviations( RSDs) of the method ranged from 1.01% to 1.61%, The method was simple, fast,sensitive and accurate,and may serve as a mass control method for residual DEHP in injection equipment.