Poloxamer， as a non-ionic surfactant， exhibits a unique triblock [polyethylene oxide-poly （propylene oxide）-polyethylene oxide] structure， which endows it with broad application potential in various fields， including solid dispersion technology， nanotechnology， gel technology， biologics， gene engineering and 3D printing. As a carrier， it enhances the solubility and bioavailability of poorly soluble drugs. In the field of nanotechnology， it serves as a stabilizer etc.， enriching preparation methods. In gel technology， its self-assembly behavior and thermosensitive properties facilitate controlled drug release. In biologics， it improves targeting efficiency and reduces side effects. In gene engineering， it enhances delivery efficiency and expression levels. In 3D printing， it provides novel strategies for precise drug release control and the production of high-quality biological products. As a versatile material， poloxamer holds promising prospects in the pharmaceutical field.

OBJECTIVES: To investigate the effect of orexin-A-mediated regulation of ionotropic glutamate receptors for promoting motor function recovery in rats with spinal cord injury (SCI). METHODS: Thirty-six newborn SD rats (aged 7-14 days) were randomized into 6 groups (n=6), including a normal control group, a sham-operated group, and 4 SCI groups with daily intrathecal injection of saline, DNQX, orexin-A, or orexin-A+DNQX for 3 consecutive days after PCI. Motor function of the rats were evaluated using blood-brain barrier (BBB) score and inclined plane test 1 day before and at 1, 3, and 7 days after SCI. For patch-clamp experiment, spinal cord slices from newborn rats in the control, sham-operated, SCI, and SCI+orexin groups were prepared, and ventral horn neurons were acutely isolated to determine the reversal potential and dynamic indicators of glutamate receptor-mediated currents under glutamate perfusion. RESULTS: At 3 and 7 days after SCI, the orexin-A-treated rats showed significantly higher BBB scores and grip tilt angles than those with other interventions. Compared with those treated with DNQX alone, the rats receiving the combined treatment with orexin and DNQX had significantly higher BBB scores and grip tilt angles on day 7 after PCI. In the patch-clamp experiment, the ventral horn neurons from SCI rat models exhibited obviously higher reversal potential and greater rise slope of glutamate current with shorter decay time than those from sham-operated and orexin-treated rats. CONCLUSIONS Orexin-A promotes motor function recovery in rats after SCI possibly by improving the function of the ionotropic glutamate receptors.
Animals ; Spinal Cord Injuries/drug therapy* ; Rats ; Rats, Sprague-Dawley ; Receptors, Ionotropic Glutamate/metabolism* ; Recovery of Function/drug effects* ; Orexins/pharmacology* ; Male ; Female ; Animals, Newborn ; Neuropeptides/pharmacology* ; Intracellular Signaling Peptides and Proteins/pharmacology*

Uncontrolled hemorrhage is the leading cause of potentially survivable combat casualty death,dominated by non-compressible hemorrhage in the torso and junctional areas.Rapid hemostasis using war trauma dressings is the mainstay of treatment for such casualties.The article reviews the research progress of novel hemostatic dressings for war trauma,including novel improved dressings,multifunctional dressings,electrospinning wound dressings,and smart dressings in order to provide references for the research on war trauma dressings.

Compared with conventional transdermal drug delivery systems, dissolving microneedles significantly enhance drug bioavailability by penetrating the stratum corneum barrier and achieving intradermal drug delivery. In order to improve the transdermal bioavailability of dexmedetomidine hydrochloride, in this study, a novel microneedle delivery system was developed for dexmedetomidine hydrochloride based on 3D printing combined with micro-molding. By systematically optimizing the microneedle geometrical parameters, array arrangement, and preparation process parameters, we determined the optimal ratio of drug-carrying matrix as 15% PVP (polyvinyl pyrrolidone) K90. The microneedles exhibited significant drug loading gradients, with mean content of (209.99±27.56) μg/patch, (405.31±30.31) μg/patch, and (621.61±34.43) μg/patch. They showed a regular pyramidal structure under SEM and handheld electron microscopy, and their mechanical strength allowed effective penetration into the stratum corneum. The surface contact angles were all < 90°, indicating excellent hydrophilicity. The microneedles dissolved completely within 10 min after skin insertion, achieving a cumulative release rate of 90% (Higuchi model, r=0.996) during 2 hours of in vitro transdermal permeation. The cytotoxicity test and hemolysis test verified good biocompatibility. Pharmacodynamic evaluation showed that the microneedle group demonstrated pain-relieving effect within 15 min, with the pain threshold at the time point of 60 min being 3 times that in the transdermal cream group. The microneedle system developed in this study not only offers an efficient drug delivery option for patients but also establishes an innovative platform for rapid percutaneous delivery of hydrophilic drugs, demonstrating significant potential in perioperative pain management.
Dexmedetomidine/pharmacokinetics* ; Printing, Three-Dimensional ; Needles ; Drug Delivery Systems/methods* ; Administration, Cutaneous ; Animals ; Microinjections/instrumentation* ; Skin Absorption ; Skin/metabolism*

Synthetic biology is a crucial tool for the development of the bio-industry and bio-economy, representing a significant aspect of new quality productive forces. As a core course for graduate students in bioengineering, Synthetic Biology plays a vital role in ensuring the supply of essential talents for the development of the bio-industry in the new era. To better serve regional economic development and provide high-level talents for China's progress in the bio-industry, we analyzed typical issues encountered in the past teaching activities, set up a multi-disciplinary teaching team, optimized the course contents, adjusted the teaching mode, and mobilized students' learning interest. With the application of scientific research project as the starting point, we guided students to think and discuss deeply through the simulation of application writing and project defense, which improved students' critical thinking and innovative thinking. With industrialization as a focus, we explored a new training model combining production, education, and research through the joint practice base of the university and enterprises introduced typical cases of biomanufacturing to encourage students to engage in scientific research. The teaching reform significantly enhances the comprehensive abilities and national sentiments of graduate students. This paper hopes to serve as a reference for colleagues engaged in teaching in this field.
Synthetic Biology/education* ; Teaching ; China ; Humans

ObjectivesTo summarize the clinical and pathological features of patients with congenital liver fibrosis （CHF）， and to investigate the differences in clinical and pathological features between patients in different age groups. MethodsA retrospective analysis was performed for the clinicopathological data of 26 patients with pathologically confirmed CHF in China-Japan Friendship Hospital from August 2005 to June 2023， and the patients were stratified by age to investigate the clinical and pathological features of patients in different age groups. ResultsAmong the 26 patients， there were 12 male patients and 14 female patients， with an age of onset of 4 — 61 years. There were 19 patients with portal hypertension type （73.08%）， 2 patients with cholangitis type （7.69%）， 4 patients with mixed type （15.38%）， and 1 patient with occult type （3.85%）. Of all 26 patients， 4 had unknown clinical symptoms， and among the 22 patients with clear clinical symptoms， 10 （45.45%） attended the hospital due to upper gastrointestinal bleeding caused by portal hypertension. Pathological manifestations included roughly normal liver parenchyma separated by fibrous septa in the portal area， with the presence of abnormal reactive bile duct hyperplasia. Denser fibrous septa and a lack of portal veins with the corresponding caliber were observed in 4 pediatric patients with disease onset before the age of 10 years， with a significant reduction or even disappearance of compensatory thin-walled blood vessels. ConclusionPortal hypertension-type CHF is the most common type in clinical practice. Patients with an early age of onset have certain histopathological features of the liver， with the presence of serious complications associated with portal hypertension. Therefore， liver biopsy should be performed for patients suspected of CHF in clinical practice， and genetic testing should be performed when necessary. Early identification and diagnosis are of great importance for improving the prognosis of patients.

To characterize the genomes of different emm-type group A Streptococcus (GAS), their virulence genes and drug resistance profiles in Tianjin City from 2011 to 2024. After PCR, a total of 42 strains with different years and emm types were selected for whole genome sequencing and multi-locus sequence typing (MLST), and the core genomes were used to generate a phylogenetic tree, after which the virulence genes and resistance genes were identified and analyzed, followed by the drug susceptibility test. In this study, the GAS strains were dominated by emm1 (50.0%) and emm12 (40.4%), and the MLST phenotypes were categorized into six types: ST36 (40.4%), ST1274 (26.1%), ST28 (23.8%), ST921 (4.7%), ST46 (2.3%), and ST403 (2.3%). There was a high consistency between their emm-types and ST types. A total of 68 virulence genes were detected in the genomes of 42 GAS strains, involving functional genes encoding exotoxin, bacterial adhesion, extracellular enzymes, etc. The virulence genes they carried were significantly different between emm1-type and emm12-type strains, such as speA. At the same time, the carrying rates of some virulence genes in the same emm-type strains changed with time, such as hyl. The resistance genes were basically the same among different emm-type strains except for the vanSE gene detected in all emm12 strains. The results of drug sensitivity showed that the GAS strains isolated in Tianjin City from 2011 to 2024 were sensitive to penicillin, cefazolin, chloramphenicol, vancomycin, and levofloxacin, while the resistance rates to erythromycin, azithromycin, clarithromycin, and clindamycin ranged from 88.5% to 100.0%, and there was a certain degree of consistency between the resistance phenotypes and the detected resistance genes. Overall, the main emm types and evolutionary features of GAS in Tianjin City from 2011 to 2024 were consistent with the dominant types in China, and the carrying rate of virulence genes and drug resistance genes differed significantly among different emm-type strains, and there were continuous evolution and variation in the prevalence of virulence genes in GAS.

OBJECTIVE To investigate the impact of vesicular stomatitis virus envelope glycopro-tein-G(VSV-G)modification on the mucosal immune efficacy of antigen-loaded engineered exosome vaccines.METHODS In vitro experiments:Dendritic cells(DCs)were divided into three groups:cell-control(treated with culture medium),receptor binding domain(RBD)(transfected with plasmid RBD),and RBD+VSV-G(co-transfected with plasmids RBD and VSV-G).Expression levels of RBD and VSV-G were assessed using Western blotting,flow cytometry,and immunofluorescence.Exosomes were extracted via ultracentrifugation,whose morphology,size distribution,and marker proteins were analyzed using transmission electron microscopy,nanoparticle tracking analysis,and Western blotting that confirmed the expressions of RBD and VSV-G in the exosomes.In vivo experiments:① Female BALB/c mice were divided into the control group Mock exosomes(Mock-Exo)(derived from the supernatant of cell-control),RBD decorated exosomes(RBD-Exo)(derived from the RBD cell supernatant),and RBD and VSV-G decorated exosomes(RBD+VSV-G-Exo)(derived from RBD+VSV-G cell supernatant).Follow-ing intranasal immunization with the respective vaccines,the nasal retention effects were evaluated using in vivo imaging.Flow cytometry was used to assess the ability to recruit immune cells to the nasal tissue.Serum RBD-specific immunoglobulin G(IgG)and mucosal immunoglobulin A(IgA)(bronchoal-veolar lavage fluid/nasal wash)were quantified at 7 and 21 d post-immunization by enzyme-linked immuno-sorbent assay.Body weight changes were monitored and key serum biochemical parameters along with histopathological damage to major organs were analyzed following immunization.② Female BALB/c mice were divided into the Mock-Exo group(intranasally inoculated with Mock-Exo),RBD+VSV-G-Exo group(intranasally inoculated with RBD+VSV-G-Exo),and RBD+VSV-G-Exo(im)group(intramus-cularly injected with RBD+VSV-G-Exo).RESULTS In vitro experiments:RBD and VSV-G were successfully expressed in cells,with positive rates of RBD+and VSV-G+cells at 64.4%and 31.2%,respectively.The extracted exosomes exhibited regular morphology and qualified purity,with a particle size of approximately 138 nm and successfully loaded RBD and VSV-G proteins.In vivo experiments:Compared to Mock-Exo and RBD-Exo,RBD+VSV-G-Exo prolonged nasal retention time to 96 h and markedly increased the numbers of CD49B+natural killer cells,CD11c+dendritic cells,and F4/80+macrophages in nasal tissues.RBD+VSV-G-Exo induced robust RBD-specific immune responses,with serum IgG titers,BALF IgA titers,and nasal wash IgA titers reaching 1∶5 215,1∶2 560,1∶1 114,respec-tively.In contrast,no RBD-specific IgA antibody titers were detected in the BALF and nasal wash of mice treated with RBD+VSV-G-Exo(im).Mice showed stable body weight gain during 30 d post-immu-nization.Major serum biochemical indices were within normal reference ranges,and no obvious patho-logical changes were observed in major organs or olfactory bulbs 7 d after immunization.CONCLU-SION VSV-G modification extends the retention time of engineered exosome vaccines in nasal tissues,enhance their ability to recruit immune cells,and induce a high-level antigen-specific respiratory mucosal immune response.

Objective To explore the protective effect of 7,8-dihydroxyflavone(7,8-DHF)on the retina of diabetic rats and its mechanism.Methods A total of 18 SPF-grade male Sprague-Dawley(SD)rats were selected and randomly divided into three groups:the normal group,the model group,and the experimental group,with six rats in each group.Rats in the normal group were fed with a normal diet,while those in the remaining two groups were fed with a high-fat emulsion through oral gavage continuously for 2 weeks to establish a diabetes model.Rats in the experimental group were provided with 7,8-DHF(5 mg?kg-1)by continuous intraperitoneal injection,while those in the normal and model groups were provided with an equal volume of normal saline.The rats in all groups received intervention once a day for 2 weeks.The changes in the body mass and fasting blood glucose(FBG)were observed before and after modeling.Besides,the changes in the retina of rats in each group were observed by fundus fluorescence angiography(FFA)after 2 weeks.Moreo-ver,the changes and apoptosis of retinal neuronal cells were detected by hematoxylin and eosin(HE)staining,CD31 im-munofluorescence,and terminal deoxynucleotidyl transferase dUTP nick end labeling(TUNEL)assays.Results After 2 weeks of continuous intervention,compared with the normal group,the body mass of rats in the model and experimental groups decreased(both P＜0.05),and the FBG increased significantly(both P＜0.05);compared with the model group,the experimental group showed an increase in the body mass(P＜0.05)and a decrease in the FBG(P＜0.05).The fundus photography and FFA of rats in the three groups did not reveal any fundus features of diabetic retinopathy.The HE staining results showed that the retina of rats in the normal and experimental groups was structurally intact,with neatly arranged cells and uniform thickness;the retinal structure of rats in the model group remained clear.However,the thickness of the inner layers of the retina of rats in the model group was thinner compared with the normal and experimental groups,exhibi-ting significant differences(both P＜0.05).The CD31 immunofluorescence assay results indicated that the CD31 immuno-fluorescence intensity values of rats in the three groups were roughly comparable,without significant differences(all P＞0.05).The TUNEL assay results suggested that the apoptosis of retinal neurons increased in rats in the model group com-pared with the normal group,exhibiting significant differences(P＜0.001);compared with the model group,the apoptosis of retinal neurons of rats in the experimental group decreased significantly,displaying significant differences(P＜0.001).Conclusion The apoptosis of retinal neurons in diabetic rats may precede vascular endothelial cell injury.7,8-DHF can improve the body mass,decrease the blood glucose level,and protect the retinal neurons in diabetic rats.

Objective To explore the protective effect of 7,8-dihydroxyflavone(7,8-DHF)on the retina of diabetic rats and its mechanism.Methods A total of 18 SPF-grade male Sprague-Dawley(SD)rats were selected and randomly divided into three groups:the normal group,the model group,and the experimental group,with six rats in each group.Rats in the normal group were fed with a normal diet,while those in the remaining two groups were fed with a high-fat emulsion through oral gavage continuously for 2 weeks to establish a diabetes model.Rats in the experimental group were provided with 7,8-DHF(5 mg?kg-1)by continuous intraperitoneal injection,while those in the normal and model groups were provided with an equal volume of normal saline.The rats in all groups received intervention once a day for 2 weeks.The changes in the body mass and fasting blood glucose(FBG)were observed before and after modeling.Besides,the changes in the retina of rats in each group were observed by fundus fluorescence angiography(FFA)after 2 weeks.Moreo-ver,the changes and apoptosis of retinal neuronal cells were detected by hematoxylin and eosin(HE)staining,CD31 im-munofluorescence,and terminal deoxynucleotidyl transferase dUTP nick end labeling(TUNEL)assays.Results After 2 weeks of continuous intervention,compared with the normal group,the body mass of rats in the model and experimental groups decreased(both P＜0.05),and the FBG increased significantly(both P＜0.05);compared with the model group,the experimental group showed an increase in the body mass(P＜0.05)and a decrease in the FBG(P＜0.05).The fundus photography and FFA of rats in the three groups did not reveal any fundus features of diabetic retinopathy.The HE staining results showed that the retina of rats in the normal and experimental groups was structurally intact,with neatly arranged cells and uniform thickness;the retinal structure of rats in the model group remained clear.However,the thickness of the inner layers of the retina of rats in the model group was thinner compared with the normal and experimental groups,exhibi-ting significant differences(both P＜0.05).The CD31 immunofluorescence assay results indicated that the CD31 immuno-fluorescence intensity values of rats in the three groups were roughly comparable,without significant differences(all P＞0.05).The TUNEL assay results suggested that the apoptosis of retinal neurons increased in rats in the model group com-pared with the normal group,exhibiting significant differences(P＜0.001);compared with the model group,the apoptosis of retinal neurons of rats in the experimental group decreased significantly,displaying significant differences(P＜0.001).Conclusion The apoptosis of retinal neurons in diabetic rats may precede vascular endothelial cell injury.7,8-DHF can improve the body mass,decrease the blood glucose level,and protect the retinal neurons in diabetic rats.