As the main product of anaerobic or aerobic glycolysis,lactic acid has long been considered to be only the metabolic waste of this process,but now researches have are gradually revealing that lactic acid,as an important signaling molecule,plays a key immune regulatory role by acting on lactic acid transporters,lactate receptors and intracellular direct sensors in immune cells.In chronic inflammatory diseases,lactic acid helps maintain a pro-inflammatory environment that encourages immune cells to remain at the site of inflammation.In the event of infection,lactic acid impairs host immunity.In the tumor microenvironment(TME),the increase in lactic acid production and the resulting TME acidification promote tumor growth and invasion,and inhibit the body's immune response to tumor antigens.This review focuses on the recent research progress on the role of lactic acid in immune regulation.

Objective To evaluate the perioperative safety of lung surgery for patients with corona virus disease 2019 (COVID-19). Methods We retrospectively analyzed the clinical data of the patients recovered from COVID-19 infection and received lung surgery from December 2022 to February 2023 in the Department of Thoracic Surgery at Beijing Hospital. Patients who received lung surgery and without COVID-19 at the same time were selected as a control group. Perioperative data between the two groups were compared. Results A total of 103 patients were included with 44 males and 49 females at an average age of (62.2±12.1) years. All surgeries were performed by uniportal video-assisted thoracoscopic surgery (VATS). Among patients who recovered from COVID-19, 53 (51.5%) received lobectomy, 30 (29.1%) received segmentectomy, and 20 (19.4%) received wedge resection. The interval between diagnosis of infection and lung surgery was ≤1 month in 32 (31.1%) patients, and >1 month in 71 (68.9%) patients. The results of virus nucleic acid test for all patients before surgery were negative. A total of 13 (12.6%) patients had positive IgM, and 100 (97.1%) patients had positive IgG. A total of 20 patients experienced perioperative complications (13 patients with pulmonary air leakage, 3 patients with chylothorax, 2 patients with atrial fibrillation, and 2 patients with severe pulmonary complications). There was one perioperative death. Comparing the patients who recovered from COVID-19 with those without COVID-19, we found no statistical difference in perioperative outcomes including surgical duration, postoperative drainage, duration of thoracic tube, and duration of postoperative stay (P>0.05). There was no significant difference in perioperative complications between the two groups (P>0.05). Multivariable logistical regression analysis demonstrated that positive IgM before surgery (OR=7.319, 95%CI 1.669 to 32.103, P=0.008), and longer duration of surgery (OR=1.016, 95%CI 1.003 to 1.028, P=0.013) were independent risk factors of perioperative complications for patients who recovered from COVID-19. Conclusion It is safe for patients recover from COVID-19 to receive lung surgery when symptoms disappear and the nucleic acid test turn negative. However, positive COVID-19 IgM is an independent risk factor for perioperative complications. We suggest that lung surgery could be performed when the nucleic acid test and COVID-19 IgM are both negative for patients recover from COVID-19 infection.

Objective:To explore the effects of nutrition management based on Patient-Generated Subjective Global Assessment (PG-SGA) on nutritional idicators,quality of life and other indicators in patients with pancreatic cancer undergoing chemotherapy, to provide guidance for the implementation of the intervention plan for pancreatic cancer patients undergoing chemotherapy.Methods:This was a randomized controlled study. From January 2021 to December 2022, 96 patients with pancreatic cancer who received chemotherapy in Shanghai Changzheng Hospital and Affiliated Cancer Hospital of Fudan University were selected using convenience sampling method and divided into the observation group and the control group according to the random number table, with 48 cases in each group. The control group was given routine nursing intervention, and the observation group was given PG-SGA-based nutrition management intervention. Patients in both groups continued the intervention until discharge. Nutritional indexes, quality of life, the score of cancer-related fatigue, sleep quality and mental state before and after intervention, intervention compliance and satisfaction after intervention, and complications during intervention of both groups were compared.Results:There were 48 patients in each group ultimately. In the control group, there were 28 males, 20 females, aged (63.33 ± 4.31) years old; in the observation group, there were 27 males, 21 females, aged (63.15 ± 4.25) years old. After intervention, the PG-SGA score, serum triacylglycerol level, and scores of Revised Piper ′s Fatigue Scale and Arsens Insomnia Scale, Self-rating Anxiety Scale and Self-rating Depression Scale in the observation group were (3.87 ± 1.16) points, (1.35 ± 0.52) mmol/L, (3.79 ± 0.67) points, and (5.31 ± 2.05), (44.55 ± 5.14), (45.15 ± 5.08) points respectively, lower than the control group ′s (5.77 ± 1.58) points, (2.04 ± 0.35) mmol/L, (4.82 ± 0.88) points, and (7.29 ± 2.14), (51.74 ± 5.18), (52.26 ± 5.11) points, the differences were statistically significant ( t values were 4.63-7.63, all P<0.05); the serum levels of retinol binding protein and transferrin were (18.13 ± 2.41) mg/L and (61.25 ± 5.34) ng/L, respectively, higher than the control group ′s (15.29 ± 2.33) mg/L and (48.31 ± 5.28) ng/L, with statistical significance ( t=5.87, 11.94, both P<0.05). The symptom domain score in the observation group after intervention was (56.17 ± 5.25) points, lower than (66.22 ± 5.57) points in the control group, while the cognitive, social, emotional, role, and physical scores were (76.35 ± 5.71 ), (77.55 ± 6.51 ), (75.87 ± 6.45), (77.38 ± 6.61), (75.75 ± 6.37) points, higher than (66.29 ± 5.39), (65.74 ± 6.34 ), (64.22 ± 6.18), (66.56 ± 6.26), (65.74 ± 6.11) points in the control group ( t values were 7.86 to 9.10, all P<0.05). Conclusions:Nutritional management based on PG-SGA could reduce the degree of cancer-induced fatigue, relieve negative emotions, improve the overall nutritional status, improve intervention compliance, reduce the occurrence of complications; improve sleep quality, quality of life, and patient ′s satisfaction.

BACKGROUND: 3D-printing is widely used in regenerative medicine and is expected to achieve vaginal morphological restoration and true functional reconstruction. Mesenchymal stem cells-derived exosomes (MSCs-Exos) were applyed in the regeneration of various tissues. The current study aimed to explore the effctive of MSCs-Exos in vaginal reconstruction. METHODS: In this work, hydrogel was designed using decellularized extracellular matrix (dECM) and gelatin methacrylate (GelMA) and silk fibroin (SF). The biological scaffolds were constructed using desktop-stereolithography.The physicochemical properties of the hydrogels were evaluated; Some experiments have been conducted to evaluate exosomes’ effect of promotion vaginal reconstruction and to explore the mechanism in this process. RESULTS: It was observed that the sustained release property of exosomes in the hydrogel both in vitro and in vitro.The results revealed that 3D scaffold encapsulating exosomes expressed significant effects on the vascularization and musule regeneration of the regenerative vagina tissue. Also, MSCs-Exos strongly promoted vascularization in the vaginal reconstruction of rats, which may through the PI3K/AKT signaling pathway. CONCLUSION The use of exosome-hydrogel composites improved the epithelial regeneration of vaginal tissue, increased angiogenesis, and promoted smooth muscle tissue regeneration. 3D-printed, lumenal scaffold encapsulating exosomes might be used as a cell-free alternative treatment strategy for vaginal reconstruction.

Objective To investigate tumor cell killing effect of superparamagnetic Fe3O4 nanoparticles with cubic phase through magneto-mechanical force under a low-frequency vibrating magnetic field ( VMF). Methods A kind of strong magnetic and irregular-shaped Fe3O4 nanoparticles with cubic phase was synthesized by coprecipitation method. The Fe3O4 nanoparticles were exposed to a self-developed VMF and cell killing efficiency of the Fe3O4-mediated magneto-mechanical force was investigated. Results VMF alone had no effects on cell viability. After Fe3O4 nanoparticles were added, the cell viability significantly decreased with prolonging the VMF treatment time and increasing the Fe3O4 nanoparticle concentration. Lactate dehydrogenase released by damaged cells also increased with prolonging the VMF exposure time. Conclusions The irregular-shaped Fe3O4 nanoparticles can transfer magneto-mechanical force to tumor cells under VMF, cause structural damage of cells and result in cell death. The VMF generator developed in this study has simple structure and it is safe for use and convenient for operation. The developed magnetic nanoparticles and the corresponding cancer cell killing technique have the potential for clinical transformation.

The bromodomain and extraterminal domain (Bet) family are the regulators of the epigenome and also the pivotal driving factors for the expression of tumor related genes that tumor cells depend on for survival and proliferation. Bromodomain-containing protein 4 (Brd4) is a member of the Bet protein family. Generally, Brd4 identifies acetylated histones and binds to the promoter or enhancer region of target genes to initiate and maintain expression of tumor related genes. Brd4 is closely related to the regulation of multiple transcription factors and chromatin modification and is involved in DNA damage repair and maintenance of telomere function, thus maintaining the survival of tumor cells. This review summarizes the structure and function of Brd4 protein and the application of its inhibitors in tumor research.
Humans ; Transcription Factors/metabolism* ; Nuclear Proteins/metabolism* ; Histones ; Cell Cycle Proteins/metabolism* ; Neoplasms/metabolism* ; Protein Domains

Ultra-rapid cooling and rewarming rate is a critical technical approach to achieve ice-free cells during the freezing and melting process. A set of ultra-rapid solid surface freeze-thaw visualization system was developed based on a sapphire flim, and experiments on droplet freeze-thaw were carried out under different cryoprotectant components, volumes and laser energies. The results showed that the cooling rate of 1 μL mixed cryoprotectant [1.5 mol/L propylene glycol (PG) + 1.5 mol/L ethylene glycol (EG) + 0.5 mol/L trehalose (TRE)] could be 9.2×10 ³ °C/min. The volume range of 1-8 μL droplets could be vitrified. After comparing the proportions of multiple cryoprotectants, the combination of equal proportion mixed permeability protectant and trehalose had the best vitrification freezing effect and more uniform crystallization characteristics. During the rewarming operation, the heating curve of glassy droplets containing gold nanoparticles was measured for the first time under the action of 400-1 200 W laser power, and the rewarming rate was up to the order of 10 ⁶ °C/min. According to the droplet images of different power rewarming processes, the laser power range for ice-free rewarming with micron-level resolution was clarified to be 1 400-1 600 W. The work of this paper simultaneously realizes the ultra-high-speed temperature ramp-up, transient visual observation and temperature measurement of droplets, providing technical means for judging the ice free droplets during the freeze-thaw process. It is conducive to promoting the development of ultra-rapid freeze-thaw technology for biological cells and tissues.
Freezing ; Vitrification ; Cryopreservation/methods* ; Trehalose ; Gold ; Rewarming ; Metal Nanoparticles ; Cryoprotective Agents ; Lasers

Objective:To evaluate the safety of thymic surgery in patients aged 65 years and over.Methods:A total of 696 patients who underwent thymectomy/thymoma resection in the Department of Thoracic Surgery of Beijing Hospital from November 2011 to March 2022 were collected and divided into two groups according to the age of 65 years old.The preoperative course of disease, MG stage, dosage of pyridostigmine bromide, American College of Anesthesiologists(ASA)score, surgical method, intraoperative bleeding, postoperative drainage, postoperative complications, Clavien-dindo score(CDC), and myasthenic crisis were recorded and statistically analyzed.Results:A total of 696 patients were enrolled, including 364 males and 332 females, aged 15~86 years, with an average age of 49.1 years.There were 309 patients with thymoma, 565 patients with MG, and 178 patients with both.There were 124 cases in the elderly group(≥65 years old)and 572 cases in the non-elderly group(<65 years old). The incidence of thymoma was higher in the elderly group(54.8 % versus 42.1 %, χ2=6.664, P=0.010), while the incidence of MG was lower(67.7 % versus 84.1 %, χ2=17.827, P<0.001). The ASA score of the elderly group was higher than that of the non-elderly group( χ2=52.372, P=0.000), and the preoperative ventilation function FEV1 and FEV1/FVC were also significantly lower than those of the non-elderly group( z=8.187, 4.580, P=0.000 for all). The drainage volume in the first 3 days after operation and postoperative drainage tube time in the elderly group were significantly higher than those in the non-elderly group( P=0.018, P=0.003). The incidence of postoperative myasthenia crisis in the elderly group was higher than that in the non-elderly group( P=0.034). There was no significant difference in the incidence of postoperative complications between the two groups, but after Clavien-dindo classification, the score of the elderly group was higher than that of the non-elderly group( P=0.003). Although the ASA score and Clavien-dindo score of the elderly group were both higher than those of the non-elderly group, there was no correlation between the two. Conclusions:Although the preoperative ASA score and pulmonary function of elderly patients were poorer than those in the non-elderly group, while the incidence of postoperative myasthenia crisis was higher, and the incidence of postoperative complications was not higher, the Clavien-dindo classification, however, was higher in elderly patients than that of the non-elderly group.After careful preoperative evaluation and strengthening perioperative management, most elderly patients can receive thymus surgery safely with acceptable risks.

Objective To explore the joint contact force, ligament tensile force and force transmission mode of foot internal structure in Down’s syndrome child (DSC) during standing. Methods The finite element models of foot were constructed based on CT image data from one DSC and one typically developing child (TDC). The models were validated by plantar pressure measurement during static standing. To simulate foot force during standing, the ground reaction force and the triceps surae force were applied as the loading condition. Contact pressure of the tibiotalar, talonavicular and calcaneocuboid joints, tensile force of the spring and plantar calcaneocuboid ligaments, and force transmission mode in transverse tarsal joints were calculated and analyzed. Results The finite element models of foot were validated to be reliable. Compared with the TDC, the DSC showed higher contact pressure at the tibiotalar joint and lower contact pressure at the talonavicular joint. The tensile force of spring and plantar calcaneocuboid ligaments of DSC was 10 times and 58 times of TDC, respectively. The forces transmitted through both mediate and lateral columns in DSC were lower than those in TDC. Conclusions Abnormal contact pressure of the tibiotalar joint, larger tensile force of midfoot ligaments and smaller force of the transverse tarsal joint were found in DSC during standing. The abnormal alteration of stress patterns in foot internal structure of DSC should be fully considered in clinical rehabilitation, so as to provide theoretical references for screening and making intervention plans for early rehabilitation, as well as designing individualized orthopedic insoles.

Objective:To evaluate the clinical characteristics and the surgical safety in patients aged 65 years and over with thymic epithelial tumor, and analyze the prognosis of 3-10 years postoperative tumor and myasthenia gravy.Methods:A total of 228 patients diagnosed as thymic tumor and undergoing surgical surgery to remove the tumor in Beijing Hospital from Jan.2011 to Dec.2018 were retrospectively enrolled.Patients were divided into a young(≤ 65 yrs)and old(>65 yrs)groups.The operation time, intra-operative bleeding, drainage volume in the first 3 days after operation, days with drainage tube after operation, postoperative days of hospital stays, the diameter of the tumors, pathological classification, Tumor-Node-Metastasis(TNM)staging, Masaoka-Koga staging, whether or not complicated with myasthenia gravis and complications were compared between two groups.The patients were followed up by outpatient or telephone, and recurrence of thymoma, survival status and improvement of myasthenia gravis were tracked.Results:There were significant differences in pathological classification between the two groups( P=0.002). The postoperative days with drainage tube were longer in patients≥65 years old than in patients<65 years old[4(2-17)days and 3(1-9), Z=2.316, P=0.021]. Thymic atrophy was more common in patients ≥ 65 years old than in patients <65 years old(10.2% and 1.7%, χ2=5.937, P=0.015). Incidence of thymoma plus myasthenia gravis were higher in patients aged <65 years than those aged ≥65years(68.2% vs.40.8%, χ2=12.240, P<0.001), and incidence of thymic hyperplasia were higher in patients aged <65 years than those aged ≥65years(58.1% and 38.8%, χ2=2.316, P=0.016). The recurrence of thymoma was a poor prognostic factor affecting the survival of patients.Meanwhile, Masaoka-Koga stage Ⅲ and Ⅳ and TNM stage Ⅲ and Ⅳ were independent risk factors for postoperative recurrence of thymoma. Conclusions:Thymectomy is safe and effective in the patients aged 65 and over, and may have a better long-term prognosis.