Sarcopenia, an age-related degenerative skeletal muscle disorder characterized by progressive loss of muscle mass, diminished strength, and impaired physical function, poses substantial challenges to global healthy aging initiatives. The pathogenesis of this condition is fundamentally rooted in mitochondrial dysfunction, manifested through defective energy metabolism, disrupted redox equilibrium, imbalanced dynamics, and compromised organelle quality control. This comprehensive review elucidates the central role of exercise-induced mitochondrial hormesis as a critical adaptive mechanism counteracting sarcopenia. Mitohormesis represents an evolutionarily conserved stress response wherein sublethal mitochondrial perturbations, particularly transient low-dose reactive oxygen species (ROS) generated during muscle contraction, activate cytoprotective signaling cascades rather than inflicting macromolecular damage. The mechanistic foundation of this process involves ROS functioning as essential signaling molecules that activate the Keap1 nuclear factor erythroid 2 related factor 2 (Nrf2) antioxidant response element pathway. This activation drives transcriptional upregulation of phase II detoxifying enzymes including superoxide dismutase (SOD) and glutathione peroxidase (GPx), thereby enhancing cellular redox buffering capacity. Crucially, Nrf2 engages in bidirectional molecular crosstalk with peroxisome proliferator activated receptor gamma coactivator 1 alpha (PGC-1α), the principal regulator orchestrating mitochondrial biogenesis through coordinated induction of nuclear respiratory factors 1 and 2 (NRF1/2) along with mitochondrial transcription factor A (Tfam), collectively facilitating mitochondrial DNA replication and respiratory complex assembly. Concurrently, exercise-induced alterations in cellular energy status, specifically diminished ATP to AMP ratios, potently activate AMP activated protein kinase (AMPK). This energy-sensing kinase phosphorylates PGC-1α while concomitantly stimulating NAD dependent deacetylase sirtuin 1 (SIRT1) activity, which further potentiates PGC-1α function through post-translational deacetylation. The integrated AMPK/PGC-1α/SIRT1 axis coordinates mitochondrial biogenesis, optimizes network architecture through regulation of fusion proteins mitofusin 1 (Mfn1), mitofusin 2 (Mfn2) and optic atrophy protein 1 (OPA1), and enhances clearance of damaged organelles via selective activation of mitophagy receptors BCL2 interacting protein 3 (Bnip1) and FUN14 domain containing 1 (FNDC1). Exercise further stimulates the mitochondrial unfolded protein response (UPRmt), increasing molecular chaperones such as heat shock protein 60 (HSP60) and HSP10 to preserve proteostasis. Within the mitochondrial matrix, SIRT3 fine-tunes metabolic flux through deacetylation of electron transport chain components, improving phosphorylation efficiency while attenuating pathological ROS emission. Distinct exercise modalities differentially engage these pathways. Aerobic endurance training primarily activates AMPK/PGC-1α signaling and UPRmt to expand mitochondrial volume and oxidative capacity. Resistance training exploits mechanical tension to acutely stimulate mechanistic target of rapamycin complex 1 (mTORC1) mediated protein synthesis while modulating dynamin related protein 1 (Drp1) phosphorylation dynamics to support mitochondrial network reorganization. High intensity interval training generates potent metabolic oscillations that rapidly amplify AMPK/PGC-1α and Nrf2 activation, demonstrating particular efficacy in insulin-resistant phenotypes. Strategically designed concurrent training regimens synergistically integrate these adaptations. Mitochondrial-nuclear communication through tricarboxylic acid cycle metabolites and mitochondrially derived peptides such as mitochondrial open reading frame of 12s rRNA-c (MOTS-c) coordinates systemic metabolic reprogramming, with exercise-responsive myokines including fibroblast growth factor 21 (FGF-21) mediating inter-tissue signaling to reduce inflammation and enhance insulin sensitivity. This integrated framework provides the scientific foundation for precision exercise interventions targeting mitochondrial pathophysiology in sarcopenia, incorporating biomarker monitoring and exploring pharmacological potentiators including nicotinamide riboside and MOTS-c mimetics. Future investigations should delineate temporal dynamics of mitohormesis signaling and epigenetic regulation to optimize therapeutic approaches for age-related muscle decline.

Objective To introduce a modified technique of right ventricular outflow tract (RVOT) reconstruction using a handmade bicuspid pulmonary valve crafted from expanded polytetrafluoroethylene (ePTFE) and to summarize the early single-center experience. Methods Patients with complex congenital heart diseases (CHD) who underwent RVOT reconstruction with a handmade ePTFE bicuspid pulmonary valve due to pulmonary regurgitation at Guangdong Provincial People’s Hospital from April 2021 to February 2022 were selected. Postoperative artificial valve function and right heart function indicators were evaluated. Results A total of 17 patients were included, comprising 10 males and 7 females, with a mean age of (18.18±12.14) years and a mean body weight of (40.94±19.45) kg. Sixteen patients underwent reconstruction with a handmade valved conduit, with conduit sizes ranging from 18 to 24 mm. No patients required mechanical circulatory support, and no in-hospital deaths occurred. During a mean follow-up period of 12.89 months, only one patient developed valve dysfunction, and no related complications or adverse events were observed. The degree of pulmonary regurgitation was significantly improved post-RVOT reconstruction and during follow-up compared to preoperative levels (P<0.001). Postoperative right atrial diameter, right ventricular diameter, and tricuspid regurgitation area were all significantly reduced compared to preoperative values (P<0.05). Conclusion The use of a 0.1 mm ePTFE handmade bicuspid pulmonary valve for RVOT reconstruction in complex CHD is a feasible, effective, and safe technique.

OBJECTIVES: To analyze the early clinical outcomes of the Xcor^TM transcatheter aortic valve replacement (TAVR) system in treating severe aortic stenosis. This study has been registered at Chinese Clinical Trial Registry (ChiCTR2200065593). METHODS: This single-arm, prospective clinical trial enrolled patients with severe aortic stenosis treated with the Xcor^TM TAVR system at the Section of Heart Valve & Coronary Artery Surgery, Guangdong Provincial People's Hospital. Perioperative and follow-up parameters were compared to evaluate differences in hemodynamic outcomes. All-cause mortality, aortic regurgitation, paravalvular leakage, cerebrovascular events, and reoperation were analyzed. RESULTS: Thirty-two patients with severe aortic stenosis were included (20 males, 12 females), with (70.9±4.3) years old and a Society of Thoracic Surgeons (STS) score of 6.45% (6.07%, 7.28%). Notably, 87.5% of patients had New York Heart Association (NYHA) class≥Ⅲ. All patients underwent successful Xcor^TM bioprosthesis implantation, achieving an immediate technical success rate of 100.0% and device success rate of 96.9%. Mean aortic valve gradient decreased from (55.21±23.17) mmHg (1 mmHg=0.133 kPa) to (8.45±5.30) mmHg, peak aortic jet velocity decreased from (4.66±0.85) m/s to (1.99±0.48) m/s, aortic valve area increased from (0.66±0.21) cm² to (2.09±0.67) cm² (all P<0.01). Intraoperative ventricular fibrillation occurred in one patient, while one case exhibited moderate prosthetic valve regurgitation and paravalvular leakage post-procedure. At 12-month follow-up, sustained improvements were observed in cardiac function, left ventricular ejection fraction, hemodynamic parameters, and SF-12 quality-of-life scores (all P<0.01). All-cause mortality was 12.5% (4/32), with 13.8% (4/29) developing moderate paravalvular leakage. CONCLUSIONS The Xcor^TM TAVR system demonstrated favorable early outcomes in severe aortic stenosis patients, significantly improving symptoms and hemodynamics while exhibiting excellent performance in preventing malignant arrhythmias and coronary obstruction.
Humans ; Male ; Female ; Aortic Valve Stenosis/surgery* ; Transcatheter Aortic Valve Replacement/methods* ; Aged ; Follow-Up Studies ; Prospective Studies ; Treatment Outcome ; Aged, 80 and over ; Heart Valve Prosthesis ; Middle Aged

Hemoglobin, the principal protein in red blood cells, is crucial for oxygen transport in the bloodstream. The quantification of hemoglobin concentration is indispensable in medical diagnostics and health management, which encompass the diagnosis of anemia and the screening of various blood disorders. Immunological methods, based on antigen-antibody interactions, are distinguished by their high sensitivity and accuracy. Consequently, it is necessary to develop hemoglobin-specific antibodies characterized by high specificity and affinity to enhance detection accuracy. In this study, we immunized a Bactrian camel (Camelus bactrianus) with human hemoglobin and subsequently constructed a nanobody library. Utilizing a solid-phase screening method, we selected nanobodies and evaluated the binding activity of the screened nanobodies to hemoglobin. Initially, human hemoglobin was used to immunize a Bactrian camel. Following four immunization sessions, blood was withdrawn from the jugular vein, and a nanobody library with a capacity of 2.85×10⁸ colony forming units (CFU) was generated. Subsequently, ten hemoglobin-specific nanobody sequences were identified through three rounds of adsorption-elution-enrichment assays, and these nanobodies were subjected to eukaryotic expression. Finally, enzyme-linked immunosorbent assay and biolayer interferometry were employed to evaluate the stability, binding activity, and specificity of these nanobodies. The results demonstrated that the nanobodies maintained robust binding activity within the temperature range of 20-40 ℃ and exhibited the highest binding activity at pH 7.0. Furthermore, the nanobodies were capable of tolerating a 10% methanol solution. Notably, among the nanobodies tested, VHH-12 displayed the highest binding activity to hemoglobin, with a half maximal effective concentration (EC₅₀) of 10.63 nmol/L and a equilibrium dissociation constant (K_D) of 2.94×10^-7 mol/L. VHH-12 exhibited no cross-reactivity with a panel of eight proteins, such as ovalbumin and bovine serum albumin, while demonstrating partial cross-reactivity with hemoglobin derived from porcine, goat, rabbit, and bovine sources. In this study, a hemoglobin-specific high-affinity nanobody was successfully isolated, demonstrating potential applications in disease diagnosis and health monitoring.
Animals ; Camelus/immunology* ; Single-Domain Antibodies/immunology* ; Hemoglobins/immunology* ; Humans ; Peptide Library

Objective To evaluate early outcomes of transthoracic pulmonary valve implantation for the treatment of moderate and severe pulmonary regurgitation by using homemade self-expanding valve (SalusTM). Methods Patients with severe pulmonary regurgitation who underwent transthoracic pulmonary valve implantation in Guangdong Provincial People’s Hospital from September 2, 2021 to November 25, 2022 were prospectively enrolled. The early postoperative complications and improvement of valve and heart function were summarized and analyzed. Results A total of 25 patients were enrolled, including 16 males and 9 females, with an average age of 24.5±1.5 years and an average weight of 57.0±3.0 kg. The mean systolic diameters of the bifurcation near the main pulmonary artery, the stenosis of the middle segment of the aorta and near the valve of the right ventricular outflow tract of the patients were 31.8±7.4 mm, 30.6±5.9 mm and 38.4±8.0 mm, respectively. All patients were successfully implanted with valves, and there were no serious complications such as death, coronary compression, stent fracture, valve displacement and infective endocarditis in the early postoperative period. The indexed left atrial longitudinal diameter, indexed right atrial longitudinal diameter, and indexed right ventricular outflow tract anteroposterior diameter decreased significantly after the operation. The degree of tricuspid and pulmonary valve regurgitation and the indexed regurgitation area decreased significantly. The above differences were statistically significant (P<0.05). Conclusion The early outcomes of transthoracic pulmonary valve implantation with homemade self-expanding pulmonary valve (SalusTM) in the treatment of severe pulmonary regurgitation is relatively good, and the long-term outcomes need to be verified by the long-term follow-up studies with large samples.

Objective To analyze and summarize the early and medium-term outcomes of self-expanding interventional pulmonary valve stent (SalusTM) for right ventricular outflow tract dysfunction with severe pulmonary valve regurgitation. Methods We established strict enrollment and follow-up criteria. Patients who received interventional pulmonary valve in transthoracic implantation in Guangdong Provincial People’s Hospital from September 2, 2021 to July 18, 2023 were prospectively included, and all clinical data of patients were collected and analyzed. Results A total of 38 patients with severe pulmonary regurgitation were included, with 23 (60.5%) males and 15 (39.5%) females. The mean age was 24.08±8.12 years, and the mean weight was 57.66±13.54 kg. The preoperative mean right ventricular end-diastolic volume index (RVEDVI) and right ventricular end-systolic volume index (RVESVI) were 151.83±42.84 mL/m2 and 83.34±33.05 mL/m2, respectively. All patients successfully underwent transcatheter self-expandable pulmonary valve implantation, with 3 (7.9%) patients experiencing valve stent displacement during the procedure. Perioperative complications included 1 (2.6%) patient of postoperative inferior wall myocardial infarction and 1 (2.6%) patient of poor wound healing. The median follow-up time was 12.00 (6.00, 17.50) months. During the follow-up period, there were no deaths or reinterventions, and no patients had recurrent severe pulmonary regurgitation. Three (7.9%) patients experienced chest tightness and chest pain, and 1 (2.6%) patient developed frequent ventricular premature beats. Compared with preoperative values, the right atrial diameter, right ventricular diameter, and tricuspid annular plane systolic excursion were significantly reduced at 6 months and 1 year postoperatively, with improvement in the degree of pulmonary regurgitation (P<0.01). Compared with preoperative values, RVEDVI and RVESVI decreased to 109.51±17.13 mL/m2 and 55.88±15.66 mL/m2, respectively, at 1 year postoperatively (P<0.01). Conclusion 　Self-expanding interventional pulmonary valve in transthoracic implantation is safe and effective for severe pulmonary valve regurgitation and shows good clinical and hemodynamic results in one-year outcome.

Objective:To summarize the ultrasonographic features and prognosis of fetal persistent vitelline artery.Methods:The prenatal ultrasound features, genetic testing results, and prognosis of a fetus with an isolated persistent vitelline artery that was diagnosed in our hospital in December 2021 were retrospectively analyzed. Relevant articles were retrieved from CNKI, VIP, Wanfang, Yiigle, PubMed, Embase, and UpToDate databases using the terms "persistent vitelline artery", "type Ⅱ single umbilical artery", and "prenatal ultrasound" in both Chinese and English. Prenatal ultrasound features and prognosis of the persistent vitelline artery in fetuses were summarized using descriptive statistical analysis.Results:(1) Case report: In this case, ultrasound at 23 gestational weeks showed that an abnormally large blood vessel deriving from the celiac artery near the superior mesenteric artery entered the placenta through the umbilical opening in parallel with the umbilical vein. Color Doppler showed a blood flow spectrum like that in the umbilical artery. The transverse section image showed that bilateral umbilical arteries were not observed in the bladder and the free segment of the umbilical cord was in the shape of the Chinese character "Lyu". No obvious other structural abnormalities and a negative result of genetic testing were observed in the fetus. Followed up to one year old, the patient showed normal growth and development. (2) Literature review: A total of five articles involving four cases were retrieved (three in English and two in Chinese). Among the five cases, including the present case, one was terminated due to left renal agenesis and abnormal heart arteries ratio revealed by prenatal ultrasound, and the remaining four cases without obvious structural abnormalities in the prenatal ultrasound were born and developed well. Histopathological examination of the umbilical cord was performed in three cases, of which two with persistent vitelline artery had a distinct internal elastic lamina, and one with remained vitelline duct.Conclusions:The prenatal ultrasound of fetal persistent vitelline artery is typically characterized by an abnormal vessel that is derived from the abdominal aorta or superior mesenteric artery and plays the function of the umbilical artery. The prognosis of the isolated persistent vitelline artery is good, but a better understanding of such embryonic abnormalities is needed as there are few relevant reports at home and abroad.

Objective:This study aimed at reviewing surgical experiences and exploring risk factors for mortality and postoperative complications in patients with infracardiac total anomalous pulmonary venous connection (TAPVC).Methods:This retrospective study included 74 infants who underwent conventional repair (28 cases) and sutureless repair (46 cases) in one hospital from February 2009 to December 2022. Clinical data were reviewed to assess risk factors for mortality and postoperative pulmonary venous obstruction (PVO). Kaplan- Meier curves and cox regressions were applied to analyze the overall survival. Cumulative incidence curve and sub-distribution hazard models were used to evaluate postoperative PVO. Results:There were 4 early deaths and 3 late deaths, and the overall survival rate was 90.5%. A total of 12 patients complicated postoperative PVO. The median follow-up was 39.4 months ( IQR: 13.3 to 73.7 months). The overall survival rate was higher in the sutureless group than the conventional group ( P=0.003). The incidence rate of postoperative PVO in the conventional group was higher than that in the sutureless group ( P= 0.008). Risk factors for recurrent PVO included longer cardiopulmonary bypass time, the increase of direct bilirubin level and international normalized ratio level before surgical repair. Conclusion:Both sutureless and conventional repairs for patients with infracardiac TAPVC can achieve acceptable postoperative outcomes. Sutureless repair has a higher survival rate and a lower incidence of re-stenosis in pulmonary veins and anastomosis.

Objective To comprehensively analyze the clinical outcomes of total cavopulmonary connection (TCPC) in the treatment of functional single ventricle combined with heterotaxy syndrome (HS). Methods A retrospective analysis was conducted on the patients with functional single ventricle and HS who underwent TCPC (a HS group) in Guangdong Provincial People's Hospital between 2004 and 2021. The analysis focused on postoperative complications, long-term survival rates, and identifying factors associated with patient survival. Early and late postoperative outcomes were compared with matched non-HS patients (a non-HS group). Results Before propensity score matching, 55 patients were collected in the HS group, including 42 males and 13 females, with a median age of 6.0 (4.2, 11.8) years and a median weight of 17.0 (14.2, 28.8) kg. Among the patients, there were 53 patients of right atrial isomerism and 2 patients of left atrial isomerism. Eight patients underwent TCPC in one stage. TCPC procedures included extracardiac conduit (n=39), intracardiac-extracardiac conduit (n=14), and direct cavopulmonary connection (n=2). Postoperative complications included infections in 27 patients, liver function damage in 19 patients, and acute kidney injury in 11 patients. There were 5 early deaths. The median follow-up time was 94.7 (64.3, 129.8) months. The 1-year, 5-year, and 10-year survival rates were 87.2%, 85.3%, and 74.3%, respectively. After propensity score matching, there were 45 patients in the HS group and 81 patients in the non-HS group. Compared to the non-HS group, those with HS had longer surgical and mechanical ventilation time, higher infection rates (P<0.05), and a 12.9% lower 10-year survival rate. Multivariate Cox regression analysis identified asplenia was a risk factor for mortality (HR=8.98, 95%CI 1.86-43.34, P=0.006). Conclusion Compared to non-HS patients, patients with HS have lower survival rates after TCPC, and asplenia is an independent risk factor for the survival of these patients.

Objective To confirm the changes of pulmonary artery pressure, neo pulmonary artery stenosis and reoperation in children with unilateral absence of pulmonary artery (UAPA) undergoing pulmonary artery reconstruction. Methods The clinical data of the infants with UAPA undergoing pulmonary artery reconstruction in our hospital from February 19, 2019 to April 15, 2021 were analyzed. Changes in pulmonary artery pressure, neo pulmonary artery stenosis and reoperation were followed up. Results Finally 5 patients were collected, including 4 males and 1 female. The operation age ranged from 13 days to 2.7 years. Cardiac contrast-enhanced CT scans were performed in all children, and 2 patients underwent pulmonary vein wedge angiography to confirm the diagnosis and preoperative evaluation. Preoperative transthoracic echocardiography and intraoperative direct pulmonary arterial pressure measurement indicated that all 5 children had pulmonary hypertension, with a mean pulmonary arterial pressure of 31.3±16.0 mm Hg. Pulmonary arterial pressure decreased immediately after pulmonary artery reconstruction to 16.8±4.2 mm Hg. The mean follow-up time was 18.9±4.7 months. All 5 patients survived during the follow-up period, and 1 patient had neo pulmonary artery stenosis or even occlusion and was re-operated. Conclusion Pulmonary artery reconstruction can effectively alleviate the pulmonary hypertension in children with UAPA. The patency of the neo pulmonary artery should be closely followed up after surgery, and re-pulmonary angioplasty should be performed if necessary.