Objective To gain insights into the biological characteristics of different populations of Culex tritaeniorhynchus within and around the Yellow Sea wetland from the perspective of the occurrence of resistance, we investigated the levels of resistance to deltamethrin and kdr gene mutation in the wetland and its peripheral areas. Methods Specimens were collected from Cx. tritaeniorhynchus populations at two monitoring sites in the Rare Bird National Nature Reserve and Tiaozi Ni Wetland Scenic Area, and also from two populations in Yancheng City and the Liuhe District of Nanjing, and the resistance of these mosquitoes to deltamethrin was determined using the CDC biotest bottle method. For each concentration of deltamethrin assessed, a random subset of exposed specimens was selected for amplification of the kdr gene fragment, followed by Sanger sequencing to identify and analyze resistance-associated mutations. Results The LC50 levels of deltamethrin among mosquitoes from the four populations in Luhe, Yancheng, the Rare Bird National Nature Reserve and the Tiaozi Ni Wetland Scenic Area were 2.048 5, 7.798 2, 3.473 3, and 17.695 5 mg/mL, respectively, with corresponding concentrations of deltamethrin ranging from 0.005 to 5.000,0.050 to 50.000,0.050 to 25.000 and 0.050 to 50.000 mg/mL, respectively. Furthermore, the ranges of the KT50 values were 11.76-107.43, 67.05-216.30,29.77-107.43 and 28.40-329.51 min; the 1-h knockdown rates were 34.58%-99.15%, 9.52%-43.80%, 55.09%-73.01%, and 10.09%-68.07%; and the 24-h mortality rates were 12.15%-67.52%,9.52%-79.56%,13.17%-82.21%, and 11.01%-78.99%, respectively. With respect to kdr gene mutation, we assayed a total of 63,70,59, and 57 mosquitoes for the four populations, for which we detected L1014F mutation frequencies of 14.29%, 35.00%, 20.34%, and 31.58%, respectively, with a majority of these mutations being heterozygous for resistance. In addition, five adult mosquitoes were identified has having synonymous mutations at site 1011[i. e. , AAT(asparagine)mutation to AAC(asparagine)]. Conclusions Our findings revealed the clear resistance of Cx. tritaeniorhynchus to deltamethrin in the Yancheng region of the Yellow Sea wetland, and the resistance phenotype and kdr frequency of Cx. tritaeniorhynchus in the wetland environment were comparable to those of Cx. tritaeniorhynchus in the wetland environment, thereby indicating that the resistance of different populations of Cx. tritaeniorhynchus was homogeneous under the pressure of different insecticide selection within and around the wetland. However, the underlying mechanisms need to be further studied.

Objective To investigate the effects of Chaihuang Qingyi Huoxue Granules on multiple organ damage induced by caerulein combined with lipopolysaccharide in mice with severe acute pancreatitis(SAP).Methods Twenty-four C57BL/6J mice were randomly divided into three groups:control(n=8),SAP(n=8)and Chaihuang Qingyi Huoxue Granules(CHQY group,n=8).Mice in SAP and CHQY groups were intraperitoneally injected with caerulein(50 μg/kg)at hourly intervals for 7 consecutive times,followed by an immediate intraperitoneal injection of lipopolysaccharide(10 mg/kg).Mice in control group received an equal volume of normal saline.After the successful establishment of the model,CHQY group mice were administered Chaihuang Qingyi Huoxue Granules[3.185 g/(kg·d)]via gavage,while control and SAP group mice received an equal volume of normal saline.Twenty-four hours post-modeling,mice were anesthetized,and serum was collected and separated for analysis of the activities of amylase(AMY),lipase(LPS),aspartate transaminase(AST),alanine transaminase(ALT)and the contents of creatinine(CREA)and urea(UREA)using an automatic biochemical analyzer.Serum levels of interleukin(IL)-1β,IL-6,IL-8,IL-18,and tumor necrosis factor-α(TNF-α)were measured by ELISA.Tissue samples from pancreas,lung,liver,kidney,and small intestine were collected for histopathological examination using hematoxylin-eosin(HE)staining and scored.The expression of nuclear factor-κB p65(NF-κB p65)was detected in all tissues by immunohistochemistry.Results Compared with control group,the activities of AMY,LPS,AST and ALT,and the contents of CREA,UREA,IL-1β,IL-6,IL-8,IL-18,and TNF-α were increased(P<0.05).Pathological injuries in the pancreas,lung,liver,kidney,and small intestine was significant,with increased pathological scores and a higher proportion of NF-κB p65 positive cells(P<0.05).Compared with SAP group,the activities of AMY,LPS,AST,ALT,and the contents of CREA,UREA,IL-1β,IL-6,IL-8,IL-18,and TNF-α in the serum of CHQY group were decreased(P<0.05).Pathological injuries in the pancreas,lung,liver,kidney and small intestine were reduced,with lower pathological scores and a decreased proportion of NF-κB p65 positive cells(P<0.05).Conclusion Chaihuang Qingyi Huoxue Granules have a certain therapeutic effect on SAP model mice,which may be related to reducing inflammation response and improving multiple organ damage such as the pancreas,lung,liver,kidney and small intestine.

Objective To establish a stable,reliable,and clinically relevant porcine model of endotoxin-induced acute respiratory distress syndrome(ARDS).Methods Ten 8-month-old male Bama minipigs were deeply sedated,followed by invasive mechanical ventilation and electrocardiographic monitoring.Lipopolysaccharide(LPS)was intravenously pumped at 600 μg/(kg·h)for 3 hours,then maintained at 15 μg/(kg·h)thereafter.Dynamic monitoring was performed at five time points after LPS injection(LPS 0,1,3,5,and 8 h),including arterial blood gas analysis and chest computed tomography(CT)scans.Pathological examination of lung tissues obtained via bronchoscopic biopsy(HE staining and transmission electron microscopy)was conducted.These indicators were comprehensively used to evaluate the success of the animal model.Results At 5 hours after LPS administration,8 minipigs developed symptoms such as skin cyanosis,elevated body temperature,and respiratory distress.The oxygenation index decreased to<300 mmHg.Chest CT scans showed diffuse pulmonary infiltrates.Histopathology revealed alveolar edema and hyaline membrane formation.Transmission electron microscopy demonstrated disruption of pulmonary blood-air barrier,depletion of lamellar bodies in type Ⅱ pneumocytes,inflammatory cell infiltration,and exudation of plasma proteins and fibrin.Compared with LPS 0 h,at LPS 8 h,the oxygenation index and arterial blood pH were significantly decreased(P<0.001),while blood lactic acid and serum potassium were significantly increased(P<0.05);serum calcium and base excess were significantly decreased(P<0.05),and the lung injury score based on HE-stained lung sections was significantly increased(P<0.01).Conclusion The porcine ARDS model established by continuous LPS injection can dynamically simulate the pathophysiological characteristics and typical pathological manifestations of clinical septic ARDS,making it an effective tool to study the pathogenesis,prevention,and treatment strategies of septic ARDS.

Objective To investigate the protective effects of the ANXA1(Annexin A1)mimetic peptide Ac2-26 on mice with severe heatstroke(HS)and its underlying mechanisms.Methods Twenty-four adult healthy male C57BL/6J mice weighing 20-25 g were randomly divided into four groups using a simple random sampling method:control group(Con group),Con+Ac2-26 group,severe heatstroke group(HS group),and severe heatstroke+Ac2-26 group(HS+Ac2-26 group),with 6 mice in each group.Mice in Con+Ac2-26 group and HS+Ac2-26 group were injected intraperitoneally with Ac2-26(6 mg/kg),and the remaining mice of two groups were injected intraperitoneally with normal saline of equivalent volume.One hour after drug administration,mice in HS group and HS+Ac2-26 group were placed in a high-temperature and high-humidity simulated environment[(37.0±0.5)℃,75%±5%humidity],while mice in Con group and Con+Ac2-26 were kept in a room temperature and humidity environment[(24±0.5)℃and 40±5%humidity]throughout the experiment.The anal temperature of the mice was recorded every 5 minutes;when the anal temperature of mice in HS group and HS+Ac2-26 group reached 42℃,they were removed from the high-temperature environment and placed in a room temperature environment for 6 hours of rewarming,after which blood samples of mice in each group were collected.Flow cytometry was used to detect the proportion of neutrophils and the expression levels of Cd11b and Cd62L(molecules related to neutrophil activation).Enzyme-linked immunosorbent assay(ELISA)was used to measure the plasma levels of tumor necrosis factor-α(TNF-α)and interleukin-6(IL-6),IL-10,and IL-4.Hematoxylin-eosin staining(HE staining)was performed to observe the pathological changes in lung,kidney and liver tissues.Furthermore,RNA sequencing(RNA-seq)was conducted to detect changes in neutrophil gene expression.Results Compared with Con group,Con+Ac2-26 group showed no significant increase in neutrophil proportion,decreased expression of CD62L and CD11b,no significant changes in cytokine levels,and no obvious pathological changes in lung,kidney,or liver tissues.Compared with HS group,the time for mice in HS+Ac2-26 group to reach an anal temperature of 42℃and the time to develop hypothermia after model establishment were both prolonged(P<0.05);the proportion of neutrophils was reduced(P<0.05);the plasma levels of pro-inflammatory cytokines TNF-α and IL-6 were decreased(P<0.05);and the plasma level of anti-inflammatory cytokine IL-10 was increased(P<0.05).HE staining results showed that compared with HS group,HS+Ac2-26 group had a reduced range of inflammatory cell infiltration in lung,kidney,and liver tissues.RNA-seq results revealed that compared with HS group,HS+Ac2-26 group had decreased expression levels of molecules related to the oxidative phosphorylation signaling pathways and neutrophil extracellular trap(NETs).Conclusion Annexin A1 mimetic peptide Ac2-26 may reduce the pro-inflammatory response and alleviate the heatstroke-induced organ histopathologic damage in heatstroke mice by inhibiting oxidative phosphorylation in heat-stressed cells and NETs formation.

Objective To investigate the anatomical and microscopic structures of interstitial fluid flow channels in the skin tissue of hand dorsum in human cadavers.Methods Totally 7 fresh cadavers within 12 hours post-mortem were included.MRI was used to observe the distribution of interstitial fluid flow from the first phalanx of the fingers to the wrist,precisely locating the flow channels.Based on imaging results,histological analyses were conducted to determine the histological characteristics of the flow channels.Furthermore,multi-immunofluorescence and microcomputed tomography(Micro-CT)techniques were employed to analyze the channels,and image post-processing was used to elucidate their anatomical structures at the microscopic level.Results After injecting a contrast agent into the first phalanx of ten finger specimens and applying repeated pressure,MRI image revealed centripetal long-range interstitial fluid flow along channels distinct from blood vessels and lymphatic vessels.Histological analysis and Micro-CT further confirmed that the flow primarily occurred within the fibrous connective tissue and adventitia of the skin.Conclusion The orderly fibrous connective tissue and adventitia in the skin form the interstitial fluid flow channels in the human hand dorsum skin,named as"stromal membrane channels"in the skin.

Objective This study aimed to provide an effective scientific basis for prevention and control of cockroaches on aircrafts by identifying cockroach-carried pathogens,and assess the insecticidal efficacy of gel bait mediated cockroach control on aircrafts,to provide technical guidance for aircraft disinsection.Methods Cassette-trapping was used to trap cockroaches,and the carried pathogens were detected using bacterial cultivation techniques.The gel bait mediated killing rate was calculated after 1,7,and 30 d by field application of gel bait.Results A total of 411 cockroaches were captured,and all were identified as Blattella germanica.26 strains of pathogenic bacteria were isolated from the trapped cockroaches.The killing rates of cockroaches were 58.8％-96.3％with 1-30 day application of gel bait.Statistically significant differences were observed in cockroach killing rates on different days(χ2=58.95,P<0.01).Conclusions B.germanica carry a large variety of pathogenic bacteria and opportunistic pathogens and are thus important infectious disease carriers.Gel bait agents have proven to be very effective against cockroaches on aircrafts.

Objective To investigate the characteristics of immune exhaustion in sepsis and analyze its association with gut microbiota translocation.Methods A total of 130 mice were randomly divided into a cecal ligation and puncture(CLP)group(n=100)and a Sham group(n=30)Mouse model of sepsis was established with CLP procedure.Flow cytometry was used to analyze the proportions of peripheral blood CD4+T and CD8+T cells and programmed cell death protein 1(PD-1)positive T cell subsets in mice.Bacterial colonization in organs such as the heart,liver and kidneys was quantified by plating homogenates of the organs.Pathological changes in immune organs were observed with HE staining.The expression and localization of CD4?,CD8?,and PD-1?cells in immune organs were detected with immunohistochemical staining,and Image J software was employed for subsequent quantification of the number of the positive cells.Results HE staining demonstrated that immune organs exhibited varying degrees of pathological damages with disease progression.Compared with the Sham mice,the CLP mice exhibited significantly increased bacterial colonization in parenchymal organs and peripheral blood(P<0.05),notably in the liver,which showed the most severe infection.In the CLP group,the proportion of CD4+T lymphocytes in peripheral blood at days 1,3,and 5 postoperatively was decreased by 56%,70.57%,and 87.42%,respectively,when compared with the Sham group(P<0.001).The proportion of CD8+T lymphocytes was decreased by 48.33%relative to the Sham group only at day 5(P<0.001).In contrast,the proportion of CD4+T cell subsets expressing PD-1 was increased to 673.08,423.08,and 600 times that of the Sham group,respectively,at the same postoperative time points(P<0.001).Immunohistochemical results showed that,in the CLP group,the proportion of CD4+T cells in the thymus,spleen,and mesenteric lymph nodes was increased to 7.65,2.66,and 3.7 times that of the Sham group,respectively,at the early-stage peak(P<0.001),and then these proportions were decreased by 82.8%(P<0.001),41.9%(P<0.01),and 60.15%(P<0.001),respectively,at the late-stage trough when compared with the early-stage peak in the corresponding organs.The proportion of CD8+positive cells was increased in the early stage and then decreased insignificantly,while the proportion of PD-1+positive cells was increased continuously,and reached 6.24,13.9,and 20.96 times that of the Sham group at the peak in the thymus,spleen,and mesenteric lymph nodes respectively(P<0.001),with their expression regions showing a rough overlap with those of CD4+cells.Conclusion During sepsis,the inflammatory response can cause severe damage to immune organs and persistent exhaustion of CD4?T lymphocytes,leading to declined defenses against infection,which may be the main causes for exacerbated gut microbiota translocation and then systemic infection.

As a cheap and effective antibiotic,sulfonamides are often used in animal husbandry.However,their residues in animal-derived foodstuffs will threaten human health.Consequently,a high-performance liquid chromatography(HPLC)method integrated with supramolecular solvent microextraction was successfully established for simultaneous quantification of sulfonamide residues sulfachlorpyridazine,sulfamethoxazole,sulfamethoxypyridazine and sulfadimethoxine in milk matrices.This approach exhibited prominent characteristics of operational simplicity,environmental sustainability,and high extraction efficiency.The supramolecular solvents prepared by tributyl octylphosphine tetrafluoroborate and tetrahydrofuran were employed as extraction solvents.The analytes underwent isolation and concentration via dispersive liquid-liquid microextraction(DLLME)prior to quantitative determination using high-performance liquid chromatography(HPLC).The composition and microscopic morphology of the supramolecular solvent were characterized through a series of analytical techniques,including phase diagram,Fourier transform infrared spectroscopy,scanning electron microscopy,and inverted fluorescence microscopy and so on.The density and pH value of supramolecular solvents were determined.The extraction conditions were optimized through the one-factor experiments.The experimental results demonstrated that under the optimal extraction conditions,the four kinds of sulfonamide antibiotics exhibited excellent linearity within respective detection range(R2 ≥ 0.9998)and the limits of detection(LOD)were 0.67-1.45 μg/L.Compared with literature methods,this approach offered some advantages such as simplicity of operation and less reagent consumption,and could be used for analysis and detection of sulfonamide antibiotic residues in milk samples.The present method provided technical support for food safety regulation and paved a new way for the application of supramolecular solvents in the field of extraction and separation.

A method for determination and targeted screening of diflorasone components in health products using ultra performance liquid chromatography-quadrupole time of flight mass spectrometry(UPLC-Q-TOF/MS)was established.Four representative diflorasone and esters(diflorasone,diflorasone diacetate,diflorasone-17-propionate,and diflorasone-21-propionate)were selected to optimize the pretreatment conditions,and 10 mL of extraction solvent dosage,15 min of extraction time and 5 g of salting-out agent as the optimal conditions were selected by response surface methodology.The results showed that the four analytes exhibited good linearity within the concentration range of 2.0?100 μg/L with the chromatographic peak area,and the correlation coefficients(R2)were all greater than 0.9990,while the results of recovery and relative standard deviation could satisfy the requirements of determination.The common characteristic ions of diflorasone and esters werem/z121 andm/z335,and their specific structures were obtained by analyzing the cleavage pathway based on the optimized determination conditions.A targeted screening method for other esters of diflorasone based on characteristic ions guidance strategy was established.This method had many advantages such as high efficiency,high sensitivity and good reproducibility,and could be used for targeted screening of diflorasone and esters in health products.The developed characteristic ion guided strategy could be employed to construct mass spectral databases for various glucocorticoids,enabling comprehensive targeted screening across a broad range of compounds.

Objective To verify the efficacy of a domestic human DNA quantification kit based on real-time fluorescence quantitative PCR in detecting the total human DNA concentration,male DNA concen-tration in mixed male/female DNA samples,the degree of DNA degradation and inhibitor tolerance.Methods Samples with different concentrations,different male/female ratios,different concentrations of inhibitors,and different degradation degrees were tested using the domestic human DNA quantification kit based on real-time fluorescence quantitative PCR.This kit was compared with a similar product on the market and was applied to the detection of DNA from real cases.Results This human DNA quan-tification kit can effectively detect human DNA as low as 0.001 65 ng/μL,and 6.25 pg/μL of male DNA in mixed samples with a male-to-female ratio of 1∶15 000.Even when the sample contains as high as 400 ng/μL of humic acid or 1 000 μmol/L of hemin alone,the DNA concentration can still be accurately detected.The degradation index can effectively characterize the degradation degree of the sample.This kit has been successfully applied in forensic practice.Conclusion This human DNA quan-tification kit is accurate and reliable in detection.It can accurately reflect the degradation of DNA and inhibitor tolerance.It has good performance in quantitative accuracy,determination of the male/female ratio in mixed samples,and inhibitor tolerance.It has application potential in forensic case examination.