BACKGROUND:We have successfully established an animal model of small ear pig in southern Yunnan province with internal tension relieving technique combined with autologous Achilles tendon for anterior cruciate ligament reconstruction,and verified the stability and reliability of the model.However,whether internal tension relieving technique can promote the ligamentalization process of autologous Achilles tendon graft has not been studied. OBJECTIVE:To investigate the differences in the process of ligamentalization between conventional reconstruction and internal reduction reconstruction of the anterior cruciate ligament by gross view,histology and electron microscopy. METHODS:Thirty adult female small ear pigs in southern Yunnan province were selected.Anterior cruciate ligament reconstruction was performed on the left knee joint with the ipsilateral knee Achilles tendon(n=30 in the normal group),and anterior cruciate ligament reconstruction was performed on the right knee joint with the ipsilateral knee Achilles tendon combined with the internal relaxation and enhancement system(n=30 in the relaxation group).The autogenous right forelimb was used as the control group;the anterior cruciate ligament was exposed but not severed or surgically treated.At 12,24,and 48 weeks after surgery,10 animals were sacrificed,respectively.The left and right knee joint specimens were taken for gross morphological observation to evaluate the graft morphology.MAS score was used to evaluate the excellent and good rate of the ligament at each time point.Hematoxylin-eosin staining was used to evaluate the degree of ligament graft vascularization.Collagen fibers and nuclear morphology were observed,and nuclear morphology was scored.Ultrastructural remodeling was evaluated by scanning electron microscopy and transmission electron microscopy. RESULTS AND CONCLUSION:(1)The ligament healing shape of the relaxation group was better at various time points after surgery,and the excellent and good rate of MAS score was higher(P<0.05).Moreover,the relaxation group could obtain higher ligament vascularization score(P<0.05).(2)The arrangement of collagen bundles and fiber bundles in the two groups gradually tended to be orderly,and the transverse fiber connections between collagen gradually increased and thickened,suggesting that the strength and shape degree of the grafts were gradually improved,but the ligament remodeling in the relaxation group was always faster than that in the normal group at various time points after surgery.(3)The diameter,distribution density,and arrangement degree of collagen fibers in the relaxation group were better than those in the normal group at all time points,especially in the comparison of collagen fiber diameter between and within the relaxation group(P<0.05).

Objective To investigate the impact of continuous nebulization therapy after lung transplantation on pulmonary function and related complications in lung transplant recipients. Methods A retrospective analysis was conducted on the general data of 71 recipients who underwent allogeneic lung transplantation at the Department of Thoracic Surgery, the First Affiliated Hospital of Zhengzhou University, from June 2013 to December 2024. Recipients were divided into observation group (those who continued nebulization therapy for more than 3 months after discharge) and control group (those who discontinued nebulization therapy on their own). The main observation indicators were pulmonary function indicators at 6 months after surgery, including forced expiratory volume in the first second as a percentage of predicted value (FEV₁% pred), forced vital capacity as a percentage of predicted value (FVC% pred), ratio of forced expiratory volume in the first second to forced vital capacity as a percentage of predicted value (FEV₁/FVC% pred), forced expiratory flow at 25%, 50% and 75% of forced vital capacity as a percentage of predicted value, and the percentage of predicted value of corrected carbon monoxide diffusion capacity measured by single-breath method, as well as the ratio of corrected carbon monoxide diffusion capacity to alveolar volume as a percentage of predicted value. Additionally, the annual incidence of postoperative pulmonary infections, survival rate and the rate of no severe airway complications were analyzed. Results At 6 months after lung transplantation, the FEV₁% pred and FVC% pred of the observation group were better than those of the control group [FEV₁% pred was 76% (60%, 91%) vs. 67% (62%, 78%), FVC% pred was (75 ± 13)% vs. (69 ± 11)%, both P<0.05]. The observation group had a lower annual incidence of pulmonary infections compared to the control group (P = 0.023), with a risk of 0.485 times that of the control group. There were no statistically significant differences between the two groups in median survival time and the rate of no severe airway complications (both P>0.05). Conclusions Continuous nebulization therapy after lung transplantation may effectively improve pulmonary function, reduce the annual incidence of pulmonary infections, and play a positive role in the long-term maintenance of pulmonary function.

Cardiac arrest (CA) is a critical condition in the field of cardiovascular medicine. Despite successful resuscitation, patients continue to have a high mortality rate, largely due to post CA syndrome (PCAS). However, the injury and pathophysiological mechanisms underlying PCAS remain unclear. Experimental animal models are valuable tools for exploring the etiology, pathogenesis, and potential interventions for CA and PCAS. Current CA animal models include electrical induction of ventricular fibrillation (VF), myocardial infarction, high potassium, asphyxia, and hemorrhagic shock. Although these models do not fully replicate the complexity of clinical CA, the mechanistic insights they provide remain highly relevant, including post-CA brain injury (PCABI), post-CA myocardial dysfunction (PAMD), systemic ischaemia/reperfusion injury (IRI), and the persistent precipitating pathology. Summarizing the methods of establishing CA models, the challenges encountered in the modeling process, and the mechanisms of PCAS can provide a foundation for developing standardized CA modeling protocols.
Animals ; Disease Models, Animal ; Post-Cardiac Arrest Syndrome/physiopathology* ; Heart Arrest/physiopathology* ; Humans ; Ventricular Fibrillation/complications*

OBJECTIVES: To verify whether hesperetin (Hes) alleviates doxorubicin (DOX)-induced cardiotoxicity by reducing inflammation via regulating the AMPK/NLRP3 pathway. METHODS: C57/bl6 mice and H9c2 cells treated with DOX to mimic cardiotoxicity were randomly divided into Sham (or control) group, DOX group, DOX+Hes group, DOX+Hes+compound C (CC, an AMPK inhibitor) group. Cardiac function and myocardial pathologies of the mice were evaluated, and the changes in H9c2 cell morphology and viability were assessed. Lactate dehydrogenase (LDH) activity in mouse myocardial tissues and H9c2 cells was measured using ELISA, and H9c2 cell apoptosis was detected with TUNEL staining. In both H9c2 cells and the myocardial tissues of the mice, cellular expression levels of TNF-α, IL-6 and IL-1β mRNAs and cleaved caspase-3, Bcl2, Bax, IL-1β, IL-18, p-AMPK, AMPK, p-mTOR, mTOR, NLRP3, ASC and caspase-1 proteins were detected using RT-PCR and Western blotting. RESULTS: DOX treatment caused cell swelling, decreased cell viability and increased LDH activity in H9c2 cells, resulting also in significantly increased cell apoptosis and cleaved caspase-3 expression and decreased Bcl2/Bax ratio. The DOX-treated mice showed obvious myocardial fiber swelling and inflammatory infiltration, decreased cardiac function and significantly increased myocardial LDH activity. In H9c2 cells, DOX treatment significantly increased the mRNA expressions of TNF-α, IL-6 and IL-1β and protein expressions of IL-1β and IL-18, lowered the expressions of p-AMPK and p-mTOR, and increased the expressions of NLRP3, ASC and caspase-1. Hes treatment obviously reduced these toxic effects of DOX in H9c2 cells, but its protective effects were blocked by application of compound C. CONCLUSIONS Hes reduces DOX-induced cardiotoxicity by inhibiting inflammation via regulating the AMPK/NLRP3 pathway.
Animals ; Doxorubicin/toxicity* ; NLR Family, Pyrin Domain-Containing 3 Protein/metabolism* ; Mice, Inbred C57BL ; Mice ; Signal Transduction/drug effects* ; Cardiotoxicity ; AMP-Activated Protein Kinases/metabolism* ; Apoptosis/drug effects* ; Cell Line ; Myocytes, Cardiac/drug effects* ; Rats

Bacterial therapy has attracted increasing attention due to its special mechanism and abundant applications. With the flourishing development of synthetic biology, therapeutic genes have been introduced into engineering bacteria to improve their antitumor efficacy. However, it is difficult to spatiotemporally control the expression of these therapeutic genes at the tumor site in vivo, thereby considerably limiting the application of engineered bacteria in tumor treatment. To resolve this problem, we constructed a temperature-responsive bacterial strain capable of triggering the expression of exogenous genes in a laser-controllable way. Noxa, a pro-apoptotic protein, is chosen to test the expression of exogenous protein and its anti-tumor effect in engineered bacteria upon laser irradiation. Firstly, Noxa was fused to the C-terminus of the bacterial outer membrane protein cytolysin A (ClyA), and then the recombinant gene fragment ClyA-Noxa was inserted into the temperature-sensitive plasmid pBV220 and the recombinant plasmid was transformed into non-pathogenic Escherichia coli MG1655. Thus, we constructed the engineering strain (TRB@Noxa) that could express Noxa on the bacterial surface. TRB@Noxa could target and colonize the tumor tissue without causing notable host toxicity. The bacterial infection triggered thrombosis in the tumor tissue, resulting in the darkness of tumor sites. In a xenograft mouse tumor model, our strategy demonstrated precise tumor targeting and strong tumor inhibition. In conclusion, we successfully constructed a new engineering bacterial strain TRB@Noxa. TRB@Noxa combined with photothermal therapy could arrest tumor growth in the absence of photosensitizers, which represents an appealing method for antitumor therapy in the future.
Escherichia coli/radiation effects* ; Animals ; Humans ; Lasers ; Mice ; Proto-Oncogene Proteins c-bcl-2/biosynthesis* ; Neoplasms/therapy* ; Genetic Engineering ; Cell Line, Tumor ; Escherichia coli Proteins/genetics*

Objective To advance China's foreign medical work to a new level by comparing medical teams from Japan,the United States,and India,focusing on transforming and upgrading to international development cooperation.Methods Liter-ature and data on the foreign medical teams of the three countries were retrieved and compared in five aspects:institutional mech-anisms,forms of assistance,foreign medical training,traditional medicine assistance,and evaluation of assistance effectiveness.Results Among the three countries,Japan and the United States showed minor differences in their approaches to foreign medical assistance,while India exhibited a distinct pattern.Conclusion China can enhance the international profile of its medical teams,consider both domestic and international interests,and continuously refine the overall strategy for foreign medical aid.Specifically,the country needs to optimize China's contribution to global health by way of strengthening international health ex-changes and cooperation and establishing a 5G smart medical technology platform for remote assistance.

Objective To investigate the application effects of cardiac resynchronization therapy(CRT)of[left bundle optimization(LOT)]and biventricular pacing(BiV)in the patients with chronic heart failure complicating left bundle branch block.Methods The single center,prospective and non-randomized controlled study method was used.Forty-two patients with heart failure meeting CRT in this center from April 2020 to April 2022 were consecutively included.Among them,32 cases adopted the BiV-CRT(BiV-CRT group)and 10 cases adopted LOT-CRT(LOT-CRT group).The pacing-making parameters,quality of life scale(SF-36)score,6-min walk test(6-MWT),ECG QRS width(QRSd),left ventricular end-diastolic diameter(LVEDD),left ventricular ejection fraction(LVEF)and New York cardiac function grade(NYHA)situation were collected before surgery,after surgery immediately and in postoperative 3,6,12 months.Their complica-tions and clinical outcomes were evaluated.Results The pacing threshold value in the LOT-CRT group was stable and lower than that in the BiV-CRT group(P＜0.05);QRSd in postoperative 12 months in the LOT-CRT group was shorter than that in the BiV-CRT group[(115.0±14.3)ms vs.(133.0±14.0)ms,P＜0.05]and 6-MWT was longer than that in the BiV-CRT group[(327.0±52.8)m vs.(274.0±52.8)m,P＜0.05],and the differences were statistically significant(P＜0.05);LVEF,LVEDD,NYHA cardiac grade and SF-36 score in postoperative 12 months were improved compared with those before implantation.The rehospitaliza-tion rate of heart failure in the LOT-CRT group was lower.Conclusion LOT-CRT could obtain a narrower QRS wave and longer 6-MWT than BiV-CRT.

Objective To investigate the underlying mechanism of microglia ferroptosis in smoke inhalation-induced(SII)brain injury.Methods Twenty SPF-grade male C57BL/6 mice were randomly divided into the control group,the SII group,the ferrostatin-1 group(Fer-1,2.5 mmol/kg)and the deferoxamine group(DFO,200 mg/kg),with 5 mice in each group.Mice in the Fer-1 group and the DFO group were intraperitoneally injected with Fer-1 and DFO 1,3 and 5 day after smoke exposure,respectively.The pathological changes of brain tissue were examined by HE staining and Prussian blue staining on the 6th day after smoke exposure.RT-qPCR was used to detect levels of inflammatory factors,brain tissue damage markers and ferroptosis markers.The contents of iron in mouse brain tissue were determined by double pyridine colorimetric assay.The contents of malondialdehyde(MDA)and lipid peroxide(LPO)in mouse brain tissue were determined by thiobarbituric acid(TBA)colorimetric assay.Superoxide dismutase(SOD)activity in mouse brain tissue was measured by xanthine oxidase assay kit.The contents of glutathione(GSH)in mouse brain tissue were determined by direct method of dithiodinitrobenzoic acid(DTNB)assay.BV2 cells were cultured in complete DMEM medium and divided into the control group,the erastin group(10 μmol/L),the Fer-1 group(erastinc stimulation combined with 5 mmol/L Fer-1 treatment)and the DFO group(erastinc stimulation combined with 50 mmol/L DFO treatment).After 24 h,cell viability was detected by CCK-8 assay,cell apoptosis was detected by Annexin V-FITC/PI flow cytometry,intracellular reactive oxygen species(ROS)production was detected by DCFDA staining,and mitochondrial membrane potential was detected by MitoTracker Red CMXRos staining.Results Compared with the control group,enhanced iron deposition and inflammation in brain tissue,elevated mRNA expression of inflammatory markers and damage markers in brain tissue,up-regulated ACSL4 and NCOA4 mRNA levels,down-regulated GPX4 and SLC7A11 mRNA levels,decreased GSH and SOD contents,and increased LPO and MDA contents were observed in brain tissue of the SII group(P＜0.05).The mRNA expression level of 7 member of solute carrier family 11(SLC7A11)was decreased in mice of the SII group.The contents of GSH and SOD were decreased,and the contents of LPO and MDA were increased(P＜0.05).Compared with the SII group,all the above parameters were reversed in the Fer-1 group and the DFO group,and the damage of mouse brain tissue was alleviated(P＜0.05).In BV2 cell experiments,compared with the control group,decreased survival rate of BV2 cells and increased apoptosis rate were found in the erastin group(P＜0.05),and increased intracellular ROS level and decreased mitochondrial membrane potential were also observed in the erastin-stimulated BV2 cells.The above parameters were opposite to those of the erastin group in the Fer-1 group and the DFO group(P＜0.05),and the oxidative damage of BV2 cells was alleviated.Conclusion The ferroptosis inhibitors Fer-1 and DFO can inhibit microglia ferroptosis and alleviate smoke inhalation-induced brain injury.

BACKGROUND:Internal tension-reduction technique is to reconstruct the anterior cruciate ligament through high-strength suture system combined with tendon.It can effectively reduce graft relaxation and frets by sharing the internal load of the knee joint,and has achieved good biomechanical results and clinical efficacy.However,whether it can reduce cartilage degeneration after anterior cruciate ligament reconstruction through stress sharing reduction has not been studied. OBJECTIVE:To investigate the effect of internal tension-reduction technique on articular cartilage degeneration in southern Yunnan small-ear pigs undergoing anterior cruciate ligament reconstruction. METHODS:Ten adult female Yunnan small-ear pigs were selected,and the ipsilateral knee Achilles tendon was taken from the left knee joint for anterior cruciate ligament reconstruction(normal group,n=10),and the ipsilateral knee Achilles tendon from the right knee joint combined with internal tension-reduction and augmentation system for anterior cruciate ligament reconstruction(tension-reduction group,n=10).One year after surgery,the experimental pigs were sacrificed,and the left and right knee cartilage was taken for hematoxylin-eosin staining,Safranin O-fast green staining,Osteoarthritis Research Society International scoring,and immunohistochemistry staining of type Ⅱ collagen,interleukin-1β,and tumor necrosis factor-alpha in the cartilage. RESULTS AND CONCLUSION:Hematoxylin-eosin staining showed that in the tension-reduction group,there were mild pathologic changes of osteoarthritis,with a low number of empty bone lacunae and no obvious pathological changes such as fibrosis or cell layer breakage;in the normal group,more severe cartilage damage,with an increased number of empty bone lacunae,loss of chondrocytes near the bone and even the formation of fissures.Safranin O-fast green staining indicated that the tension-reduction group had normal cartilage tissue thickness,flat cartilage surface,a neat cell arrangement in a polar pattern,and no swelling or apoptosis,while in the normal group,the thickness of cartilage tissue was obviously thinner,the cell arrangement was disordered with no polarity,the number of cells was reduced,obvious cartilage fractures and cartilage vacuoles formed,and the absence of cells near the central bone was obvious.The Osteoarthritis Research Society International score was significantly lower in the tension-reduction group than in the normal group(P＜0.05).Immunohistochemical findings showed that the protein expression of type Ⅱ collagen in cartilage tissue of the tension-reducing group was higher than that of the normal group(P＜0.05),and the protein expression of interleukin 1β and tumor necrosis factor ɑ in cartilage tissue was lower than that of normal group(P＜0.05).To conclude,internal tension-reduction technique can delay the degeneration of articular cartilage in Yunnan small-eared pigs following anterior cruciate ligament reconstruction.

BACKGROUND:As a dominant breed pig in southwest China,the southern Yunnan small-ear pig has been widely used as an experimental animal in the basic research of other disciplines,but there are still no reports on its application in anterior cruciate ligament reconstruction. OBJECTIVE:To establish a large animal model of the southern Yunnan small-ear pig with anterior cruciate ligament with autologous Achilles tendon was established. METHODS:Twenty adult female Yunnan small-ear pigs were equally randomized into two groups.In the autologous Achilles tendon group,the right knee anterior cruciate ligament was reconstructed with autologous Achilles tendon as a graft,while in the sham-operated group,a similar operation was performed on the right knee without any treatment of the anterior cruciate ligament.General conditions of each pig were observed and recorded before and 12 months after surgery.Ligaments and grafts were taken for gross observation and MAS scoring.Hematoxylin-eosin staining was performed to observe morphological characteristics of ligaments.The staining and arrangement of type I and type Ⅲ collagen were evaluated by immunohistochemistry.Transmission electron microscopy was used to observe the type,size,diameter,ratio,and distribution of collagen fibers in ligaments. RESULTS AND CONCLUSION:All animals had normal diet and activity,good wound healing,no obvious inflammatory reaction,no local purulent infection,and no significant changes in mental and urinary conditions compared with those before surgery.The reconstructed cruciate ligament of the knee was intact,with no stiffness and normal range of motion.Both the anterior drawer and Lachman tests were negative.Gross observation of the graft:12 months after surgery,the grafts was in good position,with good integrity,obvious tension,ligament color close to the original anterior cruciate ligament,and complete surface synovial coverage.Most of the intraarticular ligaments in the autologous Achilles tendon group were defined as MAS I type and a few were defined as MAS Ⅱ type.In the sham-operated group,the intraarticular ligament was defined as MAS I type.Hematoxylin-eosin staining indicated that,12 months after surgery,collagen fibers in the autologous Achilles tendon group began to appear bundled,isotropic,and uniformly arranged,with more obvious isotropic corrugations,and the nuclei were mainly linear or spindle-shaped,which were similar to those in normal anterior cruciate ligament tissue of the sham-operated group.Immunohistochemistry results indicated that,12 months after surgery,there was a higher expression of type I collagen and significantly less expression of type Ⅲ collagen in the reconstructed anterior cruciate ligament in the autologous Achilles tendon group.The degree of type I and type Ⅲ staining was similar in the two groups.Under the transmission electron microscope,the diameter,arrangement and density of collagen fibers in the reconstructed anterior cruciate ligament of the autologous Achilles tendon group were similar to those of the original anterior cruciate ligament at 12 months after surgery,indicating that the ligament remodeling process had been basically completed in the autologous Achilles tendon group at 12 months after surgery.Through a comprehensive evaluation of animal general conditions,ligament general view,MAS score,hematoxylin-eosin staining,immunohistochemistry,and transmission electron microscopy observation,we successfully established a large animal model of anterior cruciate ligament reconstruction using autogenous Achilles tendon in southern Yunnan small-ear pigs,with good morphological,histological and ultrastructural results.