Objective To study the microscopic structure and morphological characteristics of Zebrafish eyeball and retina at different developmental stages, and to lay a foundation for visual research model. Methods Select eight groups of zebrafish at different ages, with six fish in each group, 48 fish in total. Optical microscopy and transmission electron microscopy were used to observe the eyeball structure of Zebrafish at different developmental stages, and the thickness of retinal each layer was measured to analyze the temporal and spatial development pattern. The morphological characteristics of various cells in the retina and the way of nerve connection were observed from the microscopic and ultrastructural aspects, especially the structural differences between rod cells and cone cells. Results The retina of Zebrafish can be divided into ten layers including retinal pigment epithelial layer, rod cells and cone cells layer, outer limiting membrane, outer nuclear layer, outer plexiform layer, inner nuclear layer, inner plexiform layer, ganglion cell layer, nerve fiber layer, inner limiting membrane. Rod cells had a smaller nucleus and a higher electron density than cone cells. Photoreceptor terminals were neatly arranged in the outer plexiform layer, forming neural connections with horizontal cells and bipolar cells, and several synaptic ribbons are clearly visible within them. In Zebrafish retina, ganglion cell layer and inner plexiform layer are the earliest developed. With the growth and development of Zebrafish, the thickness of rod cells and cone cells layer and retinal pigment epithelial layer gradually increases, and the retinal structure was basically developed in about 10 weeks. Conclusion The retinal structure of Zebrafish is typical, with obvious stratification and highly differentiated nerve cells. There are abundant neural connections in the outer plexiform layer. The ocular development characteristics of Zebrafish are similar to those of most mammals.

Objective To observe the application effect and safety of continuous adductor canal block(ACB)with different doses of dexmedetomidine(DEX)combined with ropivacaine in postoperative analgesia of total knee arthroplasty(TKA).Methods Patients with TKA were enrolled as the research subjects and were divided into low-dose group,middle-dose group and high-dose group by the random number table method.At 10 min before induction of general anesthesia,all the groups were given 20 mL of 0.5％ropivacaine loading dose for ACB,placed nerve block indwelling catheter,and started ACB analgesia pump after the end of surgery.Low-dose group,middle-dose group and high-dose group were given 0.5,1.0 and 1.5 μg·kg-1 DEX+0.25％ropivacaine for a total of 100 mL,with a background dose of 4 mL·h-1and a control dose of 4 mL,and they locked for 30 min and continuously treated for 48 h.The surgical parameters and postoperative recovery quality of the two groups were compared.Visual analogue scale(VAS)was used to evaluate the pain status in resting state and motion state at 2,6,12,24 and 48 h after surgery.The number of effective compressions of self-controlled analgesia pump and the dosage of remedial analgesics at 48 h after surgery were counted and the safety evaluation was performed.Results No cases dropped out during treatment,and finally 30 cases were included in low-dose,middle-dose and high-dose groups,respectively.The first ambulation times in low-dose,middle-dose and high-dose groups were(54.22±8.37),(47.68±7.65)and(52.79±8.74)h;the time of active knee flexion 90° were(8.90±3.10),(7.20±2.70)and(8.60±2.40)d;the motion VAS scores were(3.86±0.59),(3.57±0.51)and(3.48±0.52)points at 48 h after surgery;the times of first analgesia pump compression within 48 h after surgery were(10.57±3.87),(12.45±3.63)and(13.36±3.56)h;the number of effective compressions of self-controlled analgesia pump were(6.11±2.18),(3.76±1.14)and(3.24±1.07)times;the remedial analgesia rates were 13.33％,0 and 0;at 6 h after surgery,quadriceps muscle strength scores were(4.81±0.21),(4.75±0.23)and(4.61±0.26)points,and the incidence rates of adverse drug reactions were 20.00％,6.67％and 6.67％,respectively.There were statistically significant differences in the above indicators between low-dose group and middle-dose group except for the incidence of adverse drug reactions(all P＜0.05).There were statistical differences between low-dose group and high-dose group except for the incidence of adverse drug reactions(all P＜0.05),but there were no statistical differences between middle-dose group and high-dose group(all P＞0.05).Conclusion The use of 1.0 μg·kg-1DEX combined with ropivacaine for ACB in TKA patients can achieve good postoperative analgesia effect and it has small impact on muscle strength and has good safety,thus this dose can be used as a clinical recommended dose.

Objective Viral encephalitis is an infectious disease severely affecting human health.It is caused by a wide variety of viral pathogens,including herpes viruses,flaviviruses,enteroviruses,and other viruses.The laboratory diagnosis of viral encephalitis is a worldwide challenge.Recently,high-throughput sequencing technology has provided new tools for diagnosing central nervous system infections.Thus,In this study,we established a multipathogen detection platform for viral encephalitis based on amplicon sequencing. Methods We designed nine pairs of specific polymerase chain reaction(PCR)primers for the 12 viruses by reviewing the relevant literature.The detection ability of the primers was verified by software simulation and the detection of known positive samples.Amplicon sequencing was used to validate the samples,and consistency was compared with Sanger sequencing. Results The results showed that the target sequences of various pathogens were obtained at a coverage depth level greater than 20×,and the sequence lengths were consistent with the sizes of the predicted amplicons.The sequences were verified using the National Center for Biotechnology Information BLAST,and all results were consistent with the results of Sanger sequencing. Conclusion Amplicon-based high-throughput sequencing technology is feasible as a supplementary method for the pathogenic detection of viral encephalitis.It is also a useful tool for the high-volume screening of clinical samples.

Objective:To understand the infection status, epidemiological characteristics and drug resistance of Diarrheagenic Escherichia coli (DEC) in Shanghai and provide evidence for the disease surveillance. Methods:The epidemiological data of diarrhea cases in Shanghai from 2016 to 2022 were collected from Shanghai Diarrhea Comprehensive Surveillance System, and stool samples were collected from the cases for DEC detection. The drug resistance data was obtained from Chinese Pathogen Identification Network. Statistical analysis was conducted by using χ2 and fisher test. Results:In 24 883 diarrhea cases detected during 2016-2022, the DEC positive rate was 9.13% (2 271/24 883), the single DEC positive rate was 8.83% (2 197/24 883) and the mixed DEC positive rate was 0.30% (74/24 883). The main type of DEC was Enterotoxigenic Escherichia coli (ETEC) [4.33% (1 077/24 883)]. The DEC positive rate was highest in people aged ≤5 years 18.48% (22/119). The annual peak of DEC positive rate was observed during July - September [5.91% (1 470/24 883)]. The DEC positive rate were 9.47% (554/5 847) and 9.02% (1 717/19 036) in urban area and in suburbs, respectively, Enteroaggregative Escherichia coli (EAEC) [3.98% (233/5 847)] and ETEC [4.56% (868/19 036)] were mainly detected. From 2016 to 2019, the DEC positive rate was 9.42% (1 821/19 330), while it was 8.10% (450/5 553) from 2020 to 2022, the main DEC types were ETEC (4.87%, 941/19 330) and EAEC (4.70%, 261/5 553). The multi-drug resistance rate was 40.21% (618/1 537). The top three antibiotics with high drug resistance rates were ampicillin [64.74% (995/1 537)], nalidixic acid [58.49% (899/1 537)] and tetracycline [45.09% (693/1 537)]. Conclusions:Compared with 2016- 2019, a decrease in DEC detection rate was observed during 2020-2022, and the main type of DEC detected shifted from ETEC to EAEC. The prevalence of multi-drug resistance was severe. Therefore, it is necessary to further strengthen the surveillance for DEC drug resistance and standardize the use of clinical antibiotics.

Objective:To investigate the incidence of postoperative complications in Chinese patients with gastric or colorectal cancer, and to evaluate the risk factors for postoperative complications.Methods:This was a national, multicenter, prospective, registry-based, cohort study of data obtained from the database of the Prevalence of Abdominal Complications After Gastro- enterological Surgery (PACAGE) study sponsored by the China Gastrointestinal Cancer Surgical Union. The PACAGE database prospectively collected general demographic characteristics, protocols for perioperative treatment, and variables associated with postoperative complications in patients treated for gastric or colorectal cancer in 20 medical centers from December 2018 to December 2020. The patients were grouped according to the presence or absence of postoperative complications. Postoperative complications were categorized and graded in accordance with the expert consensus on postoperative complications in gastrointestinal oncology surgery and Clavien-Dindo grading criteria. The incidence of postoperative complications of different grades are presented as bar charts. Independent risk factors for occurrence of postoperative complications were identified by multifactorial unconditional logistic regression.Results:The study cohort comprised 3926 patients with gastric or colorectal cancer, 657 (16.7%) of whom had a total of 876 postoperative complications. Serious complications (Grade III and above) occurred in 4.0% of patients (156/3926). The rate of Grade V complications was 0.2% (7/3926). The cohort included 2271 patients with gastric cancer with a postoperative complication rate of 18.1% (412/2271) and serious complication rate of 4.7% (106/2271); and 1655 with colorectal cancer, with a postoperative complication rate of 14.8% (245/1655) and serious complication rate of 3.0% (50/1655). The incidences of anastomotic leakage in patients with gastric and colorectal cancer were 3.3% (74/2271) and 3.4% (56/1655), respectively. Abdominal infection was the most frequently occurring complication, accounting for 28.7% (164/572) and 39.5% (120/304) of postoperative complications in patients with gastric and colorectal cancer, respectively. The most frequently occurring grade of postoperative complication was Grade II, accounting for 65.4% (374/572) and 56.6% (172/304) of complications in patients with gastric and colorectal cancers, respectively. Multifactorial analysis identified (1) the following independent risk factors for postoperative complications in patients in the gastric cancer group: preoperative comorbidities (OR=2.54, 95%CI: 1.51-4.28, P<0.001), neoadjuvant therapy (OR=1.42, 95%CI:1.06-1.89, P=0.020), high American Society of Anesthesiologists (ASA) scores (ASA score 2 points:OR=1.60, 95% CI: 1.23-2.07, P<0.001, ASA score ≥3 points:OR=0.43, 95% CI: 0.25-0.73, P=0.002), operative time >180 minutes (OR=1.81, 95% CI: 1.42-2.31, P<0.001), intraoperative bleeding >50 mL (OR=1.29,95%CI: 1.01-1.63, P=0.038), and distal gastrectomy compared with total gastrectomy (OR=0.65,95%CI: 0.51-0.83, P<0.001); and (2) the following independent risk factors for postoperative complications in patients in the colorectal cancer group: female (OR=0.60, 95%CI: 0.44-0.80, P<0.001), preoperative comorbidities (OR=2.73, 95%CI: 1.25-5.99, P=0.030), neoadjuvant therapy (OR=1.83, 95%CI:1.23-2.72, P=0.008), laparoscopic surgery (OR=0.47, 95%CI: 0.30-0.72, P=0.022), and abdominoperineal resection compared with low anterior resection (OR=2.74, 95%CI: 1.71-4.41, P<0.001). Conclusion:Postoperative complications associated with various types of infection were the most frequent complications in patients with gastric or colorectal cancer. Although the risk factors for postoperative complications differed between patients with gastric cancer and those with colorectal cancer, the presence of preoperative comorbidities, administration of neoadjuvant therapy, and extent of surgical resection, were the commonest factors associated with postoperative complications in patients of both categories.

Objective lo investigate the protective effect of dihydromyricetin(DHM)against exercise-induced muscle damage(EIMD)in mice and its potential mechanism. Methods Adult male C57BL/6J mice were randomly divided into control group(CG),exercise group(EG),and exercise+100 mg/kg weightd DHM(DHM)group.The intervention lasted for four weeks,during which the animals in the EG and DHM groups were subjected to exercise training for 1 h per day.The day after the training,a 90-min treadmill exercise(slope:0 and speed:18 m/min)was conducted in both EG and DHM groups.Samples of blood and gastrocnemius muscles were harvested from the three groups 24 h after the exercise,followed by the measurement of serum creatine kinase(CK)and lactate dehydrogenase(LDH)activities,total superoxide dismutase(T-SOD)activity,malondialdehyde(MDA),and skeletal muscle mitochondrial enzyme complex Ⅰ and Ⅱ activities.Histological changes in the skeletal muscle were observed by transmission electron microscopy,and the protein expressions of mitochondrial function-related pathways were detected by Western blotting. Results Skeletal muscle morphological changes and mitochondrial damage were alleviated in the DHM group compared to those in the EG.The activities of EIMD markers CK and LDH and the level of lipid peroxidation were notably repressed and the serum T-SOD activity was enhanced after DHM intervention.Western blotting demonstrated that the expressions of sirtuin type 3(SIRT3),estrogen-related receptor alpha,and peroxisome proliferator-activated receptor-gamma coactivator-1 alpha in the skeletal muscle of mice increased after the DHM intervention. Conclusion DHM can relieve EIMD in mice,possibly by promoting the recovery of the mitochondrial structure and function in the skeletal muscle of mice after high-intensity exercise via the activation of the SIRT3 signaling pathway.

Lasers are widely utilized in ion sources for mass spectrometry.They can be employed to desorb and ionize samples directly or enhance the ionization efficiency of neutral molecules through post-ionization.To investigate the ionization characteristics of the single photon ionization technique,in this work,a femtosecond laser with a wavelength of 515 nm was utilized for desorption,and a nanosecond laser with a wavelength of 118 nm for post-ionization.A laboratory-built laser desorption/laser post-ionization time-of-flight mass spectrometer(LDPI-TOFMS)was used to analyze three types of organic substances including acridines,phenothiazines,and metal porphyrins.The results demonstrated that the single photon ionization method effectively reduced the fragment generation,safeguarded the molecular ions against fragmentation,and achieved soft ionization as indicated by the adductive and characteristic molecular ions.Furthermore,a 266-nm nanosecond laser was employed as a multiphoton post-ionization source for comparison.The outcomes indicated that molecules were significantly fragmented,and more fragmented ions were generated due to the multiphoton ionization technique,which complicated the spectral analysis.The comparison further demonstrated that the single-photon post-ionization technology could be utilized to analyze a variety of organic compounds via soft ionization.LDPI-TOFMS procedure was straightforward,and did not require intricate sample preparations.The laser desorption with single photon post-ionization mass spectrometry showed potential to offer a high level of sensitivity and specificity for surfaces,thin layers,and complicated sample analysis.

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

Heme oxygenase-1(HO-1)is an inducible heme oxygenase and a catalytic enzyme for heme decomposition reactions,which can catalyze the heme decomposition into CO,biliverdin and Fe2+.HO-1 and its metabolites have anti-inflammatory,antioxidant and anti-apoptotic effects in human body,and play an important role in neurodegenerative diseases such as Alzheimer's disease,Parkinson's disease,amyotrophic lateral sclerosis,and Huntington's disease.This article will review the production,distribution,and gene structure of HO-1,the biological characteristics of its metabolites,and the role and mechanism of HO-1 in neurodegenerative diseases,in order to provide a theoretical basis for the clinical application of HO-1.

Heart failure with preserved ejection fraction(HFpEF)is a highly heterogeneous systemic condition and represents the predominant form of heart heart failure(HF)worldwide.Current pharmacotherapies for HFpEF are limited and lack specific targeted drugs.Recent studies suggest that non-pharmacological strategies serve as adjuncts to conventional pharmacological treatment,offering improvements in symptoms,quality of life,and reducing the risk of rehospitalization for HF in patients with HFpEF.These strategies include CD34 stem cell transplantation,the greater splanchnic nerve ablation,atrial septal shunting,atrial pacing,myocardial contractility modulation,left ventricular expander,baroreceptor stimulation,and others.This review comprehensively summarizes the latest clinical evidence on non-pharmacological treatments for HFpEF,with the aim of advancing the understanding of treatment strategies for this condition.