Tumors are the second leading cause of death worldwide. Exosomes are a type of extracellular vesicle secreted from multivesicular bodies, with particle sizes ranging from 40 to 160 nm. They regulate the tumor microenvironment, proliferation, and progression by transporting proteins, nucleic acids, and other biomolecules. Compared with other drug delivery systems, exosomes derived from different cells possess unique cellular tropism, enabling them to selectively target specific tissues and organs. This homing ability allows them to cross biological barriers that are otherwise difficult for conventional drug delivery systems to penetrate. Due to their biocompatibility and unique biological properties, exosomes can serve as drug delivery systems capable of loading various anti-tumor drugs. They can traverse biological barriers, evade immune responses, and specifically target tumor tissues, making them ideal carriers for anti-tumor therapeutics. This article systematically summarizes the methods for exosome isolation, including ultracentrifugation, ultrafiltration, size-exclusion chromatography (SEC), immunoaffinity capture, and microfluidics. However, these methods have certain limitations. A combination of multiple isolation techniques can improve isolation efficiency. For instance, combining ultrafiltration with SEC can achieve both high purity and high yield while reducing processing time. Exosome drug loading methods can be classified into post-loading and pre-loading approaches. Pre-loading is further categorized into active and passive loading. Active loading methods, including electroporation, sonication, extrusion, and freeze-thaw cycles, involve physical or chemical disruption of the exosome membrane to facilitate drug encapsulation. Passive loading relies on drug concentration gradients or hydrophobic interactions between drugs and exosomes for encapsulation. Pre-loading strategies also include genetic engineering and co-incubation methods. Additionally, we review approaches to enhance the targeting, retention, and permeability of exosomes. Genetic engineering and chemical modifications can improve their tumor-targeting capabilities. Magnetic fields can also be employed to promote the accumulation of exosomes at tumor sites. Retention time can be prolonged by inhibiting monocyte-mediated clearance or by combining exosomes with hydrogels. Engineered exosomes can also reshape the tumor microenvironment to enhance permeability. This review further discusses the current applications of exosomes in delivering various anti-tumor drugs. Specifically, exosomes can encapsulate chemotherapeutic agents such as paclitaxel to reduce side effects and increase drug concentration within tumor tissues. For instance, exosomes loaded with doxorubicin can mitigate cardiotoxicity and minimize adverse effects on healthy tissues. Furthermore, exosomes can encapsulate proteins to enhance protein stability and bioavailability or carry immunogenic cell death inducers for tumor vaccines. In addition to these applications, exosomes can deliver nucleic acids such as siRNA and miRNA to regulate gene expression, inhibit tumor proliferation, and suppress invasion. Beyond their therapeutic applications, exosomes also serve as tumor biomarkers for early cancer diagnosis. The detection of exosomal miRNA can improve the sensitivity and specificity of diagnosing prostate and pancreatic cancers. Despite their promising potential as drug delivery systems, challenges remain in the standardization and large-scale production of exosomes. This article explores the future development of engineered exosomes for targeted tumor therapy. Plant-derived exosomes hold potential due to their superior biocompatibility, lower toxicity, and abundant availability. Furthermore, the integration of exosomes with artificial intelligence may offer novel applications in diagnostics, therapeutics, and personalized medicine.

Objective To explore the severity of loneliness among the elderly in communities in Shanghai,and to identify factors associated with social and emotional loneliness respectively.Methods A cross-sectional study was conducted in older adults aged 65 years or above in Pudong New Area,Jing'an District and Huangpu District in Shanghai from Mar to Jun 2021.In Pudong New Area,multi-stage stratified random sampling was conducted based on the age and gender distribution of Shanghai,while in Huangpu District and Jing'an District convenience sampling was conducted.A total of 635 samples were included in the study.Loneliness was assessed using the De Jong Gierveld Loneliness Scale with social and emotional loneliness subscales.Logistic regression analyses were conducted to identify factors associated with social and emotional loneliness.Results Among the 635 participants,only 53 older adults(8.4%)were not lonely.Female(OR=0.46,95%CI:0.31-0.70),higher self-efficacy(OR=0.97,95%CI:0.94-1.00),more objective social support(OR=0.96,95%CI:0.93-0.99)were associated with less severe social loneliness.Meanwhile,higher level of education(secondary education,OR=0.56,95%CI:0.34-0.95;college or above,OR=0.30,95%CI:0.11-0.83)and higher self-efficacy(OR=0.96,95%CI:0.93-0.99)were associated with less severe emotional loneliness,while depression(OR=3.41,95%CI:1.76-6.60)and worse social capital(OR=2.02,95%CI:1.29-3.16)were associated with more severe emotional loneliness.Conclusion Up to 91.6%of the elderly in our study sample were moderately lonely or above.The factors associated with social loneliness include self-efficacy,gender and social support.The factors associated with emotional loneliness are self-efficacy,education level,depression,and social capital.

Objective To understand the respiratory protection competency of staff in hospitals.Methods Staff from six hospitals of different levels and characteristics in Beijing were selected,including doctors,nurses,medical technicians,and servicers,to conduct knowledge assessment on respiratory protection competency.According to exposure risks of respiratory infectious diseases,based on actual cases and daily work scenarios,content of respira-tory protection competency assessment was designed from three aspects:identification of respiratory infectious di-seases,transmission routes and corresponding protection requirements,as well as correct selection and use of masks.The assessment included 6,6,and 8 knowledge points respectively,with 20 knowledge points in total,all of which were choice questions.For multiple-choice questions,full marks,partial marks,and no mark were given respective-ly if all options were correct,partial options were correct and without incorrect options,and partial options were correct but with incorrect options.Difficulty and discrimination analyses on question of each knowledge point was conducted based on classical test theory.Results The respiratory protection competency knowledge assessment for 326 staff members at different risk levels in 6 hospitals showed that concerning the 20 knowledge points,more than 60％participants got full marks for 6 points,while the proportion of full marks for other questions was relatively low.Less than 10％participants got full marks for the following 5 knowledge points:types of airborne diseases,types of droplet-borne diseases,conventional measures for the prevention and control of healthcare-associated infec-tion with respiratory infectious diseases,indications for wearing respirators,and indications for wearing medical protective masks.Among the 20 knowledge questions,5,1,and 14 questions were relatively easy,medium,and difficult,respectively;6,1,4,and 9 questions were with discrimination levels of ≥0.4,0.30-0.39,0.20-0.29,and ≤0.19,respectively.Conclusion There is still much room for hospital staff to improve their respiratory protection competency,especially in the recognition of diseases with different transmission routes and the indications for wearing different types of masks.

The incidence of intrahepatic cholangiocarcinoma (ICC) continues to rise, and there are no effective drugs to treat it. The immune microenvironment plays an important role in the development of ICC and is currently a research hotspot. Icaritin (ICA) is an innovative traditional Chinese medicine for the treatment of advanced hepatocellular carcinoma. It is considered to have potential immunoregulatory and anti-tumor effects, which is potentially consistent with the understanding of "Fuzheng" in the treatment of tumor in traditional Chinese medicine. However, whether ICA can be used to treat ICC has not been reported. Therefore, in this study, sgp19/kRas, an in situ ICC mouse model with intact immune system, was selected to evaluate the efficacy of ICA in the treatment of ICC in vivo for the first time, and the effects of ICA on the tumor immune microenvironment of ICC mice were analyzed by flow cytometry. This experiment was approved by the Experimental Animal Ethics Committee of Capital Medical University (approval number: AEEI-2023-138). In this study, sgp19/kRas ICC mouse model was treated with oral gavage of 100 mg·kg^-1 ICA. We found that ICA significantly inhibited tumor growth and tumor cell proliferation in the sgp19/kRas ICC mouse model after 3 weeks of treatment. Flow cytometry analysis indicated that ICA treatment markedly reduced the proportion of M2 macrophages and increased the number of CD3⁺CD4⁺ T cells. In vitro experiments demonstrated that ICA promoted macrophage polarization towards the M1 phenotype while inhibiting polarization towards the M2 phenotype. Furthermore, transcriptomic analysis suggested that ICA enhanced Toll-like receptor 9 (TLR9) expression, influencing macrophage nitric oxide metabolism synthesis pathways and receptor-related activities, thereby regulating macrophage polarization. In summary, this study demonstrates that ICA treatment significantly delays tumor progression in sgp19/kRas ICC mouse models. Mechanistically, ICA may achieve its anti-ICC effects by upregulating TLR9 receptor expression levels, promoting macrophage polarization towards the M1 phenotype, and altering the tumor immune microenvironment.

Sturgeon cartilage has a wide range of applications as it is rich in biologically active substances such as chondroitin sulphate and protein. In this study, the safety evaluation of sturgeon cartilage peptide in NIH/3T3 and C2C12 cells was conducted, and the results showed that sturgeon cartilage peptide did not induce apoptosis and necrosis in NIH/3T3 and C2C12 cells compared to the blank control, which provides an in vitro experimental basis for the transdermal drug delivery of sturgeon cartilage peptide. Further evaluation of the scavenging activity of sturgeon cartilage peptides against the 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radicals showed that sturgeon cartilage peptides have strong antioxidant activity. A stable sturgeon cartilage peptide ointment containing 7% sturgeon cartilage peptide was prepared and analysed for its transdermal absorption in mouse skin. This experiment was approved by the Animal Ethics Committee of the Institute of Materia Medica, Chinese Academy of Medical Sciences (approval number: 00007684). It was found that the 12-hour cumulative release of sturgeon cartilage peptide ointment reached 92%. In this study, we further analyzed the ability of sturgeon cartilage peptide ointment to inhibit ear swelling in mice after xylene-induced inflammation. The sturgeon cartilage peptide ointment showed significant anti-inflammatory activity compared to the matrix group and the control group. In conclusion, the present study clearly demonstrated that sturgeon cartilage peptide has good safety and antioxidant activity, and the prepared sturgeon cartilage peptide ointment provides an experimental basis for further application of sturgeon cartilage peptide as well as the study of transdermal drug delivery.

Objective To evaluate the effects of high-fat diet on the pharmacokinetics of metronidazole in Chinese healthy adult subjects.Methods This program is designed according to a single-center,randomized,open,single-dose trial.Forty-seven healthy subjects were assigned to receive single dose of metronidazole tablets 200 mg in either fasting and high-fat diet state,and blood samples were taken at different time points,respectively.The concentrations of metronidazole in plasma were determined by high performance liquid chromatography-mass spectromentry.Results The main pharmacokinetic parameters of metronidazole in fasting state and high-fat diet state were as follows:Cmax were(4 799.13±1 195.32)and(4 044.17±773.98)ng·mL-1;tmax were 1.00 and 2.25 h;t1/2 were(9.11±1.73)and(9.37±1.79)h;AUC0_t were(5.59±1.19)x 104 and(5.51±1.18)x 104 ng·mL-1·h;AUC0_∞ were(5.79±1.33)x 104 and(5.74±1.32)× 104 ng·mL-1·h.Compared to the fasting state,the tmaxof the drug taken after a high fat diet was delayed by 1.25 h(P＜0.01),Cmax,AUC0_t,AUC0-∞ were less or decreased in different degrees,but the effects were small(all P＞0.05).Conclusion High-fat diet has little effects on the pharmacokinetic parameters of metronidazole,which does not significantly change the degree of drug absorption,but can significantly delay the time to peak.

Objective To evaluate the bioequivalence of test product and reference product in a single dose of amoxicillin clavulanate potassium tablet under fasting and fed conditions in healthy volunteers.Methods An open label,randomized,single dose,four-period,crossover bioequivalence study was designed.Fasting and postprandial tests were randomly divided into 2 administration sequence groups according to 1:1 ratio,amoxicillin clavulanate potassium tablet test product or reference product 375 mg,oral administration separately,liquid chromatography tanden mass spectrometry was applied to determine the concentration of amoxicillin and clavulanate potassium in plasma of healthy subjects after fasting or fed administration,while Phoenix WinNonlin 8.2 software were used for pharmacokinetics(PK)parameters calculation and bioequivalence analysis.Results Healthy subjects took the test product and the reference product under fasting condition,the main PK parameters of amoxicillin are as follows:Cmax were(5 075.57±1 483.37)and(5 119.86±1 466.73)ng·mL-1,AUC0_twere(1.32 × 104±2 163.76)and(1.30 × 104±1 925.11)ng·mL-1,AUC0-∞were(1.32 × 104±2 175.40)and(1.31 ×104±1 935.86)ng·mL-1;the main PK parameters of clavulanic acid are as follows:Cmax were(3 298.27±1 315.23)and(3 264.06±1 492.82)ng·mL-1,AUC0-twere(7 690.06±3 053.40)and(7 538.39±3 155.89)ng·mL-1,AUC0-∞were(7 834.81±3 082.61)and(7 671.67±3 189.31)ng·mL-1;the 90％confidence intervals of Cmax,AUC0-tand AUC0-∞ after logarithmic conversion of amoxicillin and clavulanate potassium of the two products were all within 80.00％-125.00％.Healthy subjects took the test and reference product under fed condition,the main PK parameters of amoxicillin are as follows:Cmax were(4 514.08±1 324.18)and(4 602.82±1 366.48)ng·mL-1,AUC0-twere(1.15 × 104±1 637.95)and(1.15 × 104±1 665.69)ng·mL-1,AUC0-∞ were(1.16 × 104±1 646.26)and(1.15 × 104±1 607.20)ng·mL-1;the main PK parameters of clavulanic acid are as follows:Cmax were(2 654.75±1 358.29)and(2 850.51±1 526.31)ng·mL-1,AUC0-twere(5 882.82±2 930.06)and(6 161.28±3 263.20)ng·mL-1,AUC0-∞ were(6 022.70±2 965.05)and(6 298.31±3 287.63)ng·mL-1;the 90％confidence intervals of Cmax,AUC0-t and AUC0-∞ after logarithmic conversion of amoxicillin and clavulanate potassium of the two products were all within 80.00％-125.00％.Conclusion The two formulations were bioequivalent to healthy adult volunteers under fasting and fed conditions.

Objective:To explore the correlations between serum levels of brain-derived neurotrophic factor(BDNF),interleukin-18(IL-18)and hypersensitivity C-reactive protein(hs-CRP)in patients with acute cerebral infarction and vascular cognitive impairment(VCI),and to provide some clinical ba-ses for early prevention of VCI.Methods:A total of 160 patients with acute cerebral infarction admitted in Department of Neurology of Jincheng People's Hospital from May 2019 to April 2020 were enrolled in this study and were devided into three groups according to whether or not combined with cognitive impair-ment,including no cognitive impairment group(NCI,57 cases),vascular cognitive impairment no de-mentia group(VCIND,56 cases)and vascular dementia group(VaD,47 cases).The cognitive function of all the patients were evaluated by Montreal cognitive assessment(MoCA).The National Institute of Health stroke scale(NIHSS)was used to assess the degree of neurological deficit(mild-,moderate-,se-vere-neurologic deficit group).The infarct size was calculated by Pullicino's method(small-,middle-,large-infarct group).The levels of serum BDNF and IL-18 were measured by enzyme-linked immunosor-bent assay(ELISA),and serum levels of hs-CRP were measured by immunoturbidimetry during the acute phase(0-7 d),recovery period(15-30 d)and 6 months after cerebral infarction.The effects of varying degrees of neurological deficits and different size of infarction on BDNF,IL-18 and hs-CRP were observed.The levels of serum BDNF,IL-18 and hs-CRP in the patients of the three groups with acute,convalescent and six-month cerebral infarction were compared,and their correlations with VCI were ana-lyzed.Results:Serum BDNF level and MoCA scores in mild-neurologic deficit group and small-infarct group were significantly higher than those in moderate-and severe-deficit group,middle-and large-infarct group,respectively(P＜0.05).Their levels of IL-18 and hs-CRP were significantly lower than those in moderate-and severe-deficit group,middle-and large-infarct group,respectively(P＜0.05).The levels of serum BDNF in NCI group,VCIND group and VaD group during the acute phase,convalescence and 6 months after cerebral infarction were in a significant decline,and the differences during the acute phase and recovery period were statistically significant(P＜0.05).The levels of IL-18 and hs-CRP during the acute phase,recovery period and 6 months after cerebral infarction showed a significant increasing trend with significance(P＜0.05).Correlation analysis revealed that the levels of BDNF was positively correlated with MoCA scores but negatively correlated with the severity of cognitive impairment while the expression levels of IL-18 and hs-CRP were negatively correlated with MoCA scores but positively correlated with the severity of cognitive impairment.Conclusion:Serum BDNF,IL-18 and hs-CRP are involved in the patho-logical process of occurrence and development of VCI in the patients with acute cerebral infarction.BDNF has a protective effect on VCI while IL-18 and hs-CRP cause severe cognitive impairment.The levels of se-rum BDNF、IL-18 and hs-CRP in the patients with acute ischemic cerebral infarction are closely related to the severity of cognitive impairment and can be used as biomarkers of early diagnosis of VCI.

Objective To investigate the short-term efficacy and safety of chemotherapy induced by nimotuzumab(NTZ)combined with TP regimen and sequential concurrent chemoradiotherapy in patients with epidermal growth factor receptor positive(EGFR-positive)locally advanced nasopharyngeal carcinoma.Methods A total of 48 patients with stage Ⅲ to Ⅳ A nasopharyngeal carcinoma in Guizhou Provincial People's Hospital from January 2020 to December 2022 were prospectively enrolled,and were randomized into two groups:NTP(NTZ+docetaxel/albumin-paclitaxel+cisplatin)group and TP(Docetaxel/albumin-paclitaxel+cisplatin)group(24 cases per group)by random number table method.After 2 or 3 cycles of induction chemotherapy in NTP group,NTZ was sequentially used in combination with cisplatin for concurrent chemoradiotherapy.Immunohistochemistry was used to detect the EGFR expression level,exploring EGFR expression intensity and the therapeutic effect of NTZ in NTP group patients.Meanwhile,short-term efficacy,withdrawal rate and toxic side effects were compared between the two groups after induction chemotherapy.Results In NTP group,the positive expression rate of EGFR was 100％,and EGFR expression intensity significantly correlated with the efficacy of NTZ-combined induction therapy(P<0.05).After induction chemotherapy,the objective response rate(ORR)of cervical lymph nodes in NTP group was significantly higher than that in TP group(75％vs.45.8％,P=0.039).The primary lesion ORR and overall(primary lesion and cervical lymph node)ORR showed no significant difference between the two groups(P>0.05).Comparison of adverse reactions between the two groups during induction therapy:leukopenia and gastrointestinal reaction in NTP group were lower than those in TP group(P<0.05),but rash was higher than those in TP group(P<0.05).There was no significant difference in liver function,hemoglobin and thrombocytopenia between two groups(P>0.05).Conclusions EGFR expression intensity varies in nasopharyngeal carcinoma tissues,with higher levels indicating greater clinical benefit of combined induction therapy with NTZ.NTZ combined with TP induction regimen demonstrates good short-term efficacy and safety for cervical lymph nodes in patients with locally advanced nasopharyngeal carcinoma.

Purpose::Ischemia and hypoxia are the main factors limiting limb replantation and transplantation. Static cold storage (SCS), a common preservation method for tissues and organs, can only prolong limb ischemia time to 4 - 6 h. The normothermic machine perfusion (NMP) is a promising method for the preservation of tissues and organs, which can extend the preservation time in vitro by providing continuous oxygen and nutrients. This study aimed to evaluate the difference in the efficacy of the 2 limb preservation methods. Methods::The 6 forelimbs from beagle dogs were divided into 2 groups. In the SCS group ( n = 3), the limbs were preserved in a sterile refrigerator at 4 °C for 24 h, and in the NMP group ( n = 3), the perfusate prepared with autologous blood was used for the oxygenated machine perfusion at physiological temperature for 24 h, and the solution was changed every 6 h. The effects of limb storage were evaluated by weight gain, perfusate biochemical analysis, enzyme-linked immunosorbent assay, and histological analysis. All statistical analyses and graphs were performed using GraphPad Prism 9.0 one-way or two-way analysis of variance. The p value of less than 0.05 was considered to indicate statistical significance. Results::In the NMP group, the weight gained percentage was 11.72% ± 4.06%; the hypoxia-inducible factor-1α contents showed no significant changes; the shape of muscle fibers was normal; the gap between muscle fibers slightly increased, showing the intercellular distance of (30.19 ± 2.83) μm; and the vascular α-smooth muscle actin (α-SMA) contents were lower than those in the normal blood vessels. The creatine kinase level in the perfusate of the NMP group increased from the beginning of perfusion, decreased after each perfusate change, and remained stable at the end of perfusion showing a peak level of 4097.6 U/L. The lactate dehydrogenase level of the NMP group increased near the end of perfusion and reached the peak level of 374.4 U/L. In the SCS group, the percentage of weight gain was 0.18% ± 0.10%, and the contents of hypoxia-inducible factor-1α increased gradually and reached the maximum level of (164.85 ± 20.75) pg/mL at the end of the experiment. The muscle fibers lost their normal shape and the gap between muscle fibers increased, showing an intercellular distance of (41.66 ± 5.38) μm. The contents of vascular α-SMA were much lower in the SCS group as compared to normal blood vessels.Conclusions::NMP caused lesser muscle damage and contained more vascular α-SMA as compared to SCS. This study demonstrated that NMP of the amputated limb with perfusate solution based on autologous blood could maintain the physiological activities of the limb for at least 24 h.