Fluorescence anisotropy(FA)analysis has many advantages such as no requirement of separation,high throughput and real-time detection,and thus has been widely used in many fields,including biochemical analysis,food safety detection,environmental monitoring,etc.However,due to the small volume or mass of the target,its combination with the fluorescence probe cannot produce significant signal change.To solve this issue,researchers often use nanomaterials to enhance the mass or volume of fluorophore to improve the sensitivity.Nevertheless,this FA amplification strategy also has some disadvantages.Firstly,nanomaterials are easy to quench fluorescence.As a result,the FA value is easily influenced by light scattering,which reduces the detection accuracy.Secondly,fluorescent probes in most methods require complex modification steps.Therefore,it is necessary to develop new FA probes that do not require the amplification of volume and mass or modification.As a new kind of nanomaterials,luminescent metal-organic framework(MOF)has a large volume(or mass)and strong fluorescence emission.It does not require additional signal amplification materials.As a consequence,it can be used as a potential FA probe.This study successfully synthesized a lanthanide metal organic framework(Ce-TCPP MOF)using cerium ion(Ce3+)as the central ion and 5,10,15,20-tetra(4-carboxylphenyl)porphyrin(H2TCPP)as the ligand through microwave assisted method,and used it as a novel unmodified FA probe to detect phosphate ions(Pi).In the absence of Pi,Ce-TCPP MOF had a significant FA value(r).After addition of Pi,Pi reacted with Ce3+in MOF and destroyed the structure of MOF into the small pieces,resulting in a decrease in r.The experimental results indicated that with the increase of Pi concentration,the change of the r of Ce-TCPP MOF(Δr)gradually increased.The Δr and Pi concentration showed a good linear relationship within the range of 0.5-3.5 μmol/L(0.016-0.108 mg/L).The limit of detection(LOD,3σ/k)was 0.41 μmol/L.The concentration of Pi in the Jialing River water detected by this method was about 0.078 mg/L,and the Pi value detected by ammonium molybdate spectrophotometry was about 0.080 mg/L.The two detection results were consistent with each other,and the detection results also meet the ClassⅡwater quality standard,proving that this method could be used for the detection of Pi in complex water bodies.

Objective To determine the appropriate internal reference protein for the Western Blot(WB)assay to detect proteins related to S-phase kinase-associated protein 2(Skp2).Methods This study was carried out with several human tumor cell lines.The intracellular Skp2 protein level was down-regulated by transient transfection of shRNA plasmid,and glyceraldehyde-3-phosphate dehydrogenase(GAPDH)and β-actin were used as internal reference proteins respectively for WB assay.The relative expression levels and correlations of GAPDH,β-actin and Skp2 were evaluated.Results When the relative expression level of Skp2 changed,the relative expression levels of GAPDH in human non-small cell lung cancer cells H1299(1.32 × 106±7.86 × 104),human cervical cancer cell HeLa(6.59 × 106±1.79 × 106)and human liver cancer cell HepG2(3.13 × 106±2.87 × 105)all changed significantly(all P＜0.05).The correlation results showed that for human non-small cell lung cancer cells A549(R=0.825 8)and H1299(R=0.906 2),and there was a certain correlation between Skp2 and GAPDH expression levels(all P＜0.05).Conclusion β-actin is more suitable to be applied as reference protein in WB assay for Skp2 protein.

Objective:To analyze the relationship of thrombus composition and regulatory T cell expression with clinical outcome in acute ischemic stroke(AIS)patients with thrombectomy.Methods:A total of 44 AIS patients who underwent thrombectomy in the Department of Neurology of Shaoxing Hospital from June 2021 to October 2022 were enrolled.All thrombus specimens were subjected to hematoxylin-eosin staining and immunohistochemistry.Semi-quantitative analysis was performed to determine the content of red blood cells,fibrinogen/platelets,and regulatory T(CD4+CD25+)cells.Clinical data,vascular recanalization status,and neurologic outcomes at 3 months after thrombectomy were collected.A modified Rankin Scale score of 0-2 was defined as a favorable outcome.Result:Among 44 patients with complete thrombus data there were 15 cases of red cell type,11 cases of mixed type and 18 cases of fibrin/platelet type.There was a significant difference in trial of ORG 10172 in acute stroke treatment(TOAST)etiological classification among the three groups(P<0.01),while no significant differences were found in other general clinical and surgical data(all P>0.05).According to the TOAST etiology,28 cases were classified as large atherosclerosis type and 16 cases as cardioembolic type.The proportion of red blood cells in thrombus was significantly higher in patients with large atherosclerosis type than that in those with cardioembolic type[58.0%(44.2%,72.5%)vs.24.5%(12.7%,48.0%),P<0.01].The ratio of fibrin to platelet in patients with cardiogenic embolism was significantly higher than that in patients with large atherosclerosis[73.0%(49.2%,84.5%)vs.40.0%(25.2%,54.5%),P<0.01).Among the 44 patients,19 had good while 25 had poor neurological outcomes.Univariate binary logistic regression analysis showed that age,operation time,CD4+CD25+T cell number were correlated with the functional outcomes of the patients(all P<0.05).Multivariate binary logistic regression analysis showed that thrombus CD4+CD25+T cell count was an independent factor affecting the functional outcome of patients(OR=1.369,95%CI:1.101-1.701,P<0.01).Conclusion:There is no significant correlation of erythrocyte and fibrin/platelet components in thrombus with functional outcome in AIS patients,but an increased count of regulatory T cells associates with good functional outcome.

Objective:To investigate the association between baseline hemoglobin level and early neurologic deterioration(END)after intravenous thrombolysis in patients with acute ischemic stroke(AIS).Methods:Data of AIS patients who received intravenous thrombolytic therapy at multiple hospitals across the country between January 2017 and July 2020 were collected from the online database Acute Stroke Patients for Stroke Management Quality Evaluation(CASE-Ⅱ,NCT04487340).Binary logistic regression analysis was used to study the factors affecting the occurrence of END after intravenous thrombolytic therapy,and the correlation between baseline hemoglobin level and END was investigated by limiting cubic spline curve analysis.Results:A total of 8162 patients were included.Patients with END had lower baseline hemoglobin levels(136 and 140 g/L,P<0.01)and higher rates of anemia(24.2%and 16.9%,P<0.01)compared with non-END patients.Binary logistic regression analysis showed that baseline hemoglobin level(OR=0.995,95%CI:0.991-0.999,P<0.05)and anemia(OR=1.238,95%CI:1.055-1.454,P<0.01)were independently correlated with the occurrence of END after intravenous thrombolysis in AIS patients.Restricted cubic spline regression showed that there was a U-shaped relationship between hemoglobin level and the risk of END after intravenous thrombolysis in AIS patients(P<0.01),although this relationship was only significant in male patients(P<0.05)and not in female patients(P>0.05).Conclusion:There is a correlation between baseline hemoglobin level and the risk of END in AIS patients after intravenous thrombolysis,especially in male patients,in whom both lower and higher hemoglobin level may increase the risk of END.

Trichinosis is a global food-borne zoonotic parasitic disease caused by Trichinella spiralis(T.spiralis),which causes serious harm to animal production,and the public health safety of humans and animals.T.spiralis has a complex devel-opment history,and its entire life cycle is completed in the same host.To coexist with the host,it has evolved various immune escape mechanisms for avoiding immune clearance by the host,thus establishing long-term chronic infection.In this study,to aid in understanding the pathogenic mechanism of T.spiralis,the immune escape mechanism of Trichinella is discussed from three aspects:the molecular role of antigens in various stages,the immune regulatory effect on the host,and the formation of cysts to generate immune isolation.

AIM:To investigate the effects of sodium hydrosulfide(NaHS)on hexokinase 2(HK2)-nucleo-tide-binding oligomerization domain-like receptor protein 3(NLRP3)-gasdermin D(GSDMD)pathway and pyroptosis in-duced by lung ischemia/reperfusion(I/R)in rats.METHODS:Male Sprague-Dawley rats were divided into 6 groups:control group,control+NaHS group,I/R group,low-dose NaHS+I/R(L+I/R)group,medium-dose NaHS+I/R(M+I/R)group,and high-dose NaHS+I/R(H+I/R)group,with 6 rats in each group.The NaHS was administered via intraperi-toneal injection at 1.5 mL,30 min before modeling.The left lung tissues were collected 30 min after ischemia and 1 h af-ter reperfusion,and the wet/dry weight ratio and total lung water content were recorded.Hematoxylin-eosin(HE)staining was used to examine lung tissue morphological changes.The levels of malondialdehyde(MDA),myeloperoxidase(MPO)and lactate in lung tissues were measured with test kits.ELISA was employed to determine the levels of interleukin-1β(IL-1β)and IL-18.The expression of glycolysis-and pyroptosis-related indicators was analyzed by Western blot,qRT-PCR and immunofluorescence staining.RESULTS:Compared with control group,the rats in NaHS group showed no signifi-cant differences in all laboratory tests(P>0.05).The rats in I/R group exhibited significant lung injury,oxidative stress,increased lactate level,and up-regulated glycolysis and pyroptosis(P<0.05 or P<0.01).Compared with I/R group,the indicators in L+I/R group showed a downward trend(P<0.01)or no difference(P>0.05),while those in M+I/R group dis-played a significant reduction(P<0.05 or P<0.01).However,the indexes in H+I/R group exhibited no significant dif-ferences in these tests(all P>0.05).CONCLUSION:A moderate dose(56 μmol·L-1·kg-1)of NaHS mitigated the oc-currence of pyroptosis by inhibiting the HK2-NLRP3-GSDMD pathway,thus contributing to the attenuation of lung I/R in-jury in rats.

Objective To explore the effects of different immobilization modes on the setup errors for lower limb radiation therapy guided by ExacTrac image guidance system.Methods Totally 145 patients who completed radiation therapy for lower limb tumors at some hospital from October 2019 to November 2022 were selected retrospectively,and then divided into a vacuum negative pressure pad group(Group A,n=46),a thermoplastic membrane group(Group B,n=50)and a thong shoe group(Group C,n=49)based on their immobilization methods.For the three groups of patients the target areas were outlined and the radiotherapy plans were formulated according to unified standards.ExacTrac image guidance system was used for position verification and setup error recording at six directions of anterior-posterior(AP),head-foot(SI),left-right(LR),rotation around AP(Yaw),rotation around SI(Roll)and rotation around LR(Pitch).Results The differences between the 3 groups in LR,AP and Roll directions were all statistically significant(P＜0.05);the setup errors in LR,AP and Roll directions were significantly lower in group B than in the other 2 groups(P＜0.05),and the setup errors in LR and AP directions were significantly lower in group C than in group A(P＜0.05).The setup errors with the three immobilization modes all met clinical requirements after correction.Conclusion Thermoplastic membrane immobilization may enhance the accuracy of body fixation and decrease setup errors during lower limb radiotherapy,and it's recommended be prioritized for body immobilization.[Chinese Medical Equipment Journal,2024,45(3):61-65]