Hepatitis B virus （HBV） exclusively infects liver parenchymal cells and forms covalently closed circular DNA （cccDNA） within their nuclei. HBV cccDNA serves as the essential template for viral gene transcription， the sole source of progeny virus production， and the key driver of viral antigen expression， and it is the molecular basis for the persistence of HBV infection. Therefore， elimination and/or functional silencing of cccDNA is the key to eradicate chronic HBV infection. This article discusses the critical scientific issues that need to be solved during elimination of the harm of HBV infection from the perspectives of the synthesis， transcription， and clearance of cccDNA， as well as the impact of nonparenchymal cells on cccDNA， in order to provide a reference for eradicating HBV infection in the future.

Organoid-on-a-chip technology represents a promising interdisciplinary advancement that merges two cutting-edge biomedical platforms: stem cell-derived organoids and microfluidics-based organ-on-a-chip systems. Organoids are self-organizing three-dimensional (3D) cell cultures that mimic the key structural and functional features of in vivo organs. However, traditional organoid culture systems are often static, lacking dynamic environmental cues and suffering from limitations such as batch-to-batch variability, low stability, and low throughput. Organ-on-a-chip platforms, by contrast, utilize microfluidic technologies to simulate the dynamic physiological microenvironment of human tissues and organs, enabling more controlled cell growth and differentiation. By integrating the advantages of organoids and organ-on-a-chip technologies, organoid-on-a-chip systems transcend the limitations of conventional 3D culture models, offering a more physiologically relevant and controllable in vitro platform. In organoid-on-a-chip systems, stem cells or pre-formed organoids are cultured in micro-engineered environments that mimic in vivo conditions, enabling precise control over fluid flow, mechanical forces, and biochemical cues. Specifically, these platforms employ advanced strategies including bio-inspired 3D scaffolds for structural support, precise spatial cell patterning via 3D bioprinting, and integrated biosensors for real-time monitoring of metabolic activities. These synergistic elements recreate complex extracellular matrix signals and ensure high structural fidelity. Based on structural complexity, organoid-on-a-chip systems are classified into single-organoid and multi-organoid types, forming a trajectory from unit biomimicry to systemic simulation. Single-organoid chips focus on highly biomimetic units by integrating vascular, immune, or neural functions. Multi-organoid chips simulate inter-organ crosstalk and systemic homeostasis, advancing complex disease modeling and PK/PD evaluation. This emerging technology has demonstrated broad application potential in multiple fields of biomedicine. Organoid-on-a-chip systems can recapitulate organ developmentin vitro, facilitating research in developmental biology. They mimic organ-specific physiological activities and mechanisms, showing promising applications in regenerative medicine for tissue repair or replacement. In disease modeling, they support the reconstruction of models for neurodegenerative, inflammatory, infectious, metabolic diseases, and cancers. These platforms also enable in vitro drug testing and pharmacokinetic studies (ADME). Patient-derived chips preserve genetic and pathological features, offering potential for precision medicine. Additionally, they reduce species differences in toxicology, providing human-relevant data for environmental, food, cosmetic, and drug safety assessments. Despite progress, organoid-on-a-chip systems face challenges in dynamic simulation, extracellular matrix (ECM) variability, and limited real-time 3D imaging, requiring improved materials and the integration of developmental signals. Current bottlenecks also include the high technical threshold for automation and the lack of standardized validation frameworks for regulatory adoption. Meanwhile, the concept of a “human-on-a-chip” has been proposed to mimic whole-body physiology by integrating multiple organoid modules. This approach enables systemic modeling of drug responses and toxicity, with the potential to reduce animal testing and revolutionize drug development. Future advancements in bio-responsive hydrogels and flexible biosensors will further empower these platforms to bridge the gap between bench-side research and personalized clinical interventions. In conclusion, organoid-on-a-chip technology offers a transformative in vitro model that closely recapitulates the complexity of human tissues and organ systems. It provides an unprecedented platform for advancing biomedical research, clinical translation, and pharmaceutical innovation. Continued development in biomaterials, microengineering, and analytical technologies will be essential to unlocking the full potential of this powerful tool.

Organoid-on-a-chip technology represents a promising interdisciplinary advancement that merges two cutting-edge biomedical platforms: stem cell-derived organoids and microfluidics-based organ-on-a-chip systems. Organoids are self-organizing three-dimensional (3D) cell cultures that mimic the key structural and functional features of in vivo organs. However, traditional organoid culture systems are often static, lacking dynamic environmental cues and suffering from limitations such as batch-to-batch variability, low stability, and low throughput. Organ-on-a-chip platforms, by contrast, utilize microfluidic technologies to simulate the dynamic physiological microenvironment of human tissues and organs, enabling more controlled cell growth and differentiation. By integrating the advantages of organoids and organ-on-a-chip technologies, organoid-on-a-chip systems transcend the limitations of conventional 3D culture models, offering a more physiologically relevant and controllable in vitro platform. In organoid-on-a-chip systems, stem cells or pre-formed organoids are cultured in micro-engineered environments that mimic in vivo conditions, enabling precise control over fluid flow, mechanical forces, and biochemical cues. Specifically, these platforms employ advanced strategies including bio-inspired 3D scaffolds for structural support, precise spatial cell patterning via 3D bioprinting, and integrated biosensors for real-time monitoring of metabolic activities. These synergistic elements recreate complex extracellular matrix signals and ensure high structural fidelity. Based on structural complexity, organoid-on-a-chip systems are classified into single-organoid and multi-organoid types, forming a trajectory from unit biomimicry to systemic simulation. Single-organoid chips focus on highly biomimetic units by integrating vascular, immune, or neural functions. Multi-organoid chips simulate inter-organ crosstalk and systemic homeostasis, advancing complex disease modeling and PK/PD evaluation. This emerging technology has demonstrated broad application potential in multiple fields of biomedicine. Organoid-on-a-chip systems can recapitulate organ developmentin vitro, facilitating research in developmental biology. They mimic organ-specific physiological activities and mechanisms, showing promising applications in regenerative medicine for tissue repair or replacement. In disease modeling, they support the reconstruction of models for neurodegenerative, inflammatory, infectious, metabolic diseases, and cancers. These platforms also enable in vitro drug testing and pharmacokinetic studies (ADME). Patient-derived chips preserve genetic and pathological features, offering potential for precision medicine. Additionally, they reduce species differences in toxicology, providing human-relevant data for environmental, food, cosmetic, and drug safety assessments. Despite progress, organoid-on-a-chip systems face challenges in dynamic simulation, extracellular matrix (ECM) variability, and limited real-time 3D imaging, requiring improved materials and the integration of developmental signals. Current bottlenecks also include the high technical threshold for automation and the lack of standardized validation frameworks for regulatory adoption. Meanwhile, the concept of a “human-on-a-chip” has been proposed to mimic whole-body physiology by integrating multiple organoid modules. This approach enables systemic modeling of drug responses and toxicity, with the potential to reduce animal testing and revolutionize drug development. Future advancements in bio-responsive hydrogels and flexible biosensors will further empower these platforms to bridge the gap between bench-side research and personalized clinical interventions. In conclusion, organoid-on-a-chip technology offers a transformative in vitro model that closely recapitulates the complexity of human tissues and organ systems. It provides an unprecedented platform for advancing biomedical research, clinical translation, and pharmaceutical innovation. Continued development in biomaterials, microengineering, and analytical technologies will be essential to unlocking the full potential of this powerful tool.

As a strategic emerging industry, biomanufacturing faces core challenges in achieving precise optimization and efficient scale-up of fermentation processes. This review focuses on two critical aspects of fermentation-real-time sensing and intelligent control-and systematically summarizes the advancements in online monitoring technologies, artificial intelligence (AI)-driven optimization strategies, and digital twin applications. First, online monitoring technologies, ranging from conventional parameters (e.g., temperature, pH, and dissolved oxygen) to advanced sensing systems (e.g., online viable cell sensors, spectroscopy, and exhaust gas analysis), provide a data foundation for real-time microbial metabolic state characterization. Second, conventional static control relying on expert experience is evolving toward AI-driven dynamic optimization. The integration of machine learning technologies (e.g., artificial neural networks and support vector machines) and genetic algorithms significantly enhances the regulation efficiency of feeding strategies and process parameters. Finally, digital twin technology, integrating real-time sensing data with multi-scale models (e.g., cellular metabolic kinetics and reactor hydrodynamics), offers a novel paradigm for lifecycle optimization and rational scale-up of fermentation. Future advancements in closed-loop control systems based on intelligent sensing and digital twin are expected to accelerate the industrialization of innovative achievements in synthetic biology and drive biomanufacturing toward higher efficiency, intelligence, and sustainability.
Artificial Intelligence ; Fermentation ; Bioreactors/microbiology* ; Neural Networks, Computer ; Algorithms ; Biotechnology/methods*

ObjectiveTo investigate the anatomical features of three-dimensional （3D） reconstruction of the hepatic pedicle based on the Laennec’s capsule， as well as its application value in the development of extra-sheath dissection/occlusion clamp and precise hepatectomy. MethodsA retrospective analysis was performed for the abdominal contrast-enhanced CT data of 100 patients without anatomical abnormalities of the hepatic pedicle in The General Hospital of Western Theater Command from January 2021 to June 2024. The Hisense CAS system combined with the 3D U-net deep learning algorithm was used for 3D reconstruction of the hepatic pedicle at the level of Laennec’s capsule， and the hepatic pedicle was measured in terms of the length， outer diameter， and angle of the main trunk and branches. An extra-sheath hepatic pedicle dissection/occlusion clamp was developed based on the above measurements， and a total of 30 patients scheduled for right hemihepatectomy were enrolled and randomly divided into device group and control group， with 15 patients in each group. The two groups were compared in terms of hepatic pedicle handling time， time of operation， intraoperative blood loss， and the incidence rate of bile duct injury. The independent-samples t test was used for comparison of continuous data between two groups， and the Fisher’s exact test was used for comparison of categorical data between two groups. ResultsThe results of 3D reconstruction revealed four variants in the main trunk branches of the hepatic pedicle， with type Ⅰ （left-right branching） accounting for 88% （88/100）， type Ⅱ （trifurcation type） accounting for 5% （5/100）， type Ⅲ （right anterior branching） accounting for 5% （5/100）， and type Ⅳ （special type） accounting for 2% （2/100）. The outer diameter of the main hepatic pedicle was 24.10±6.16 mm， the length of the left main branch was 20.59±6.38 mm， and the length of the right main branch was 21.99±7.98 mm. Compared with the control group， the device group had significantly shorter hepatic pedicle handling time （14.10±1.30 minutes vs 17.50±2.00 minutes， t=-5.620， P=0.001） and time of operation （217.00±28.28 minutes vs 241.87±19.49 minutes， t=-2.804， P=0.009）. The device group had a significantly lower incidence rate of bile duct injury than the control group （0 vs 20%， P=0.031）. Conclusion3D reconstruction based on the Laennec’s capsule can accurately display the anatomical variations of the hepatic pedicle. The extra-sheath hepatic pedicle dissection/occlusion clamp developed based on such data can optimize the process of hepatic pedicle management and improve surgical safety， and therefore， it holds promise for clinical application.

Objective To investigate the effect of different exercise modes on people with nonalcoholic fatty liver disease(NAFLD)and obesity,thereby providing evidence-based exercise prescriptions for the rehabilitation of this population.Methods Patients diagnosed with NAFLD and obesity through health screenings at the Physical Examination Center of First Affiliated Hospital of Army Medical University from January to September 2023 were selected and assigned into three groups by random number table method,with 52 cases in each group.The aerobic group underwent aerobic exercise,the resistance group underwent resistance exercise,and the combined group underwent a combination of aerobic and resistance exercise for a duration of 12 weeks.The liver function indicators[including alanine aminotransferase(ALT),gamma-glutamyl transferase(GGT),aspartate aminotransferase(AST),albumin,and bilirubin],BMI,waist circumference,blood glucose,and triglyceride(TG)levels in each group were detected and compared.The improvement effect of different exercise modes on the above various indexes in patients with NAFLD and obesity was analyzed.Results After intervention,BMI and waist circumference were significantly decreased in each group(P<0.05);and the ALT,GGT,albumin,bilirubin,TG and blood glucose of the combined group were significantly improved compared with those before intervention(P<0.05).Resistance exercise had a better improvement effect on the ALT,GGT,AST and TG than aerobic exercise(P<0.05),while which had no significant difference in the albumin,bilirubin,BMI,waist circumference or blood glucose compared with aerobic exercise(P>0.05).The improvement effects of aerobic+resistance combined exercise on the BMI,waist circumference,albumin,bilirubin and TG were better than those of aerobic exercise and resistance exercise alone(P<0.05),while which had no significant difference in the improvement of the ALT,GGT or AST compared with resistance exercise alone(P>0.05).Conclusion For people with NAFLD and obesity,a combined aerobic and resistance exercise intervention is recommended,which can improve the liver function,body fat distribution and related metabolic indexes of patients,with better treatment results.

Objective:To evaluate the value of spectral CT quantitative parameters in predicting microvascular invasion (MVI) of hepatocellular carcinoma (HCC).Methods:A total of 100 HCC patients who underwent surgical resection and were pathologically diagnosed in the Affiliated Cancer Hospital of Xiangya Medical College of Central South University from January 2020 to January 2023 were retrospectively enrolled. According to pathological grading, the patients were divided into the microvascular invasion group (invasion group, n=60) and the non-vascular invasion group (non-invasion group, n=40). Serological indicators and spectral CT quantitative parameters were compared between the two groups. Receiver operating characteristic (ROC) curve was used to analyze the value of spectral CT quantitative parameters in predicting MVI of HCC. Results:The serum alpha-fetoprotein (AFP) level in the invasion group was higher than that in the non-invasion group, with a statistically significant difference ( P<0.05). There were no statistically significant differences in serum carcinoembryonic antigen (CEA) and carbohydrate antigen 199 (CA-199) levels between the two groups (all P>0.05). In the invasion group, arterial phase iodine concentration, arterial phase normalized iodine concentration, venous phase iodine uptake reduction rate, arterial phase effective atomic number, and energy spectrum curve slope were all higher than those in the non-invasion group, with statistically significant differences (all P<0.05); there were no statistically significant differences in venous phase iodine concentration, venous phase normalized iodine concentration, and venous phase effective atomic number between the two groups (all P>0.05). The rates of peritumoral enhancement in the arterial phase and irregular tumor margin in the invasion group were higher than those in the non-invasion group, with statistically significant differences (all P<0.05); there was no statistically significant difference in tumor capsule between the two groups ( P>0.05). ROC curve analysis showed that the areas under the curve (AUC) of arterial phase iodine concentration, arterial phase normalized iodine concentration, venous phase iodine uptake reduction rate, arterial phase effective atomic number, and energy spectrum curve slope for predicting MVI in HCC were 0.812, 0.885, 0.726, 0.823, and 0.788, respectively. Conclusions:Spectral CT quantitative parameters are helpful to improve the preoperative diagnostic efficiency of MVI in HCC and can effectively predict MVI in HCC. Especially, arterial phase normalized iodine concentration has high application value in judging whether there is MVI in HCC.

Body weight abnormalities, including overweight, obesity, and underweight, have become a dual public health challenge in Chinese adults: overweight and obesity lead to a variety of chronic complications, while underweight increases the risks of malnutrition, sarcopenia, and organ dysfunction. To systematically address these issues, multidisciplinary experts in endocrinology, sports science, nutrition, and psychiatry from various regions have held multiple weight management seminars. Based on the latest epidemiological data and clinical evidence, they expanded the guideline to include assessment and intervention strategies for underweight, in addition to the core content of obesity management. This guideline outlines the etiological mechanisms, evaluation methods, and multidimensional management strategies for overweight and obesity, covering key areas such as diagnosis and assessment, medical nutrition therapy, exercise prescription, pharmacological intervention, and psychological support. It is intended to provide a scientific and standardized approach to weight management across the adult population, aiming to curb the rising prevalence of obesity, mitigate complications associated with abnormal body weight, and improve nutritional status and overall quality of life.

Objective·To compare the safety and short-term outcomes of robot-assisted versus laparoscopic-assisted proximal gastrectomy combined with double-flap esophagogastrostomy in the treatment of early upper gastric cancer.Methods·A retrospective cohort study was conducted to analyze the clinical and pathological data of 31 early gastric cancer patients who underwent proximal gastrectomy combined with double-flap esophagogastrostomy for gastrointestinal reconstruction at the Department of Gastrointestinal Surgery,Renji Hospital,Shanghai Jiao Tong University School of Medicine,from September 2023 to March 2024.Based on the surgical approach,patients were divided into the robot-assisted surgery group(robotic group,20 cases)and the laparoscope-assisted surgery group(laparoscopic group,11 cases).General clinical data,intraoperative conditions,and postoperative recovery between the two groups were compared.At the 6-month postoperative follow-up,upper gastrointestinal radiography and esophagogastroscopy were performed to assess anastomotic stricture and gastroesophageal reflux disease.Additionally,the gastric cancer-specific module of the European Organization for Research and Treatment of Cancer(EORTC),Quality of Life Questionnaire-Stomach 22(QLQ-STO22),was used to evaluate the patients' quality of life.Results·The general data of the two groups,including gender,age,preoperative comorbidities,American Society of Anesthesiologists(ASA)classification,Siewert classification,and pathological staging of tumors,showed no statistically significant differences(all P>0.05).All patients successfully underwent the procedure without conversion to open surgery.The time for gastroesophageal anastomosis was significantly shorter in the robotic group compared to the laparoscopic group[(31.09±8.23)min vs(43.73±8.83)min,P<0.001],while there were no statistically significant differences in other intraoperative and postoperative parameters,including operative time,intraoperative blood loss,number of lymph nodes removed,duration of gastric tube placement,time to start a liquid diet,length of postoperative hospital stay,and incidence of postoperative complications(all P>0.05).At the 6-month postoperative follow-up,30 patients completed the follow-up,with one patient lost to follow-up in the robotic group.Upper gastrointestinal radiography and esophagogastroscopy results showed that only one patient in the laparoscopic group developed an anastomotic stricture,while one patient in the robotic group developed grade A and one developed grade B gastroesophageal reflux disease(GERD).In addition,one patient in the laparoscopic group also developed grade B GERD.The incidences of GERD and anastomotic stricture showed no statistically significant differences between the two groups(both P>0.05).EORTC QLQ-STO22 results indicated that the robotic group had significantly lower scores in the dimensions of dysphagia,gastroesophageal reflux,and dietary restrictions,as well as in the total score,compared to the laparoscopic group(all P<0.05).Conclusion·Robot-assisted proximal gastrectomy combined with double-flap esophagogastrostomy is safe and feasible.It shortens anastomosis time and offers potential advantages in postoperative functional recovery and quality of life improvement.