Objective To explore the application value of dual-phase dual-energy CT (DECT) perfusion imaging in preoperative lung function assessment of lung cancer patients. Methods Data were collected from patients with stageⅠA non-small cell lung cancer who underwent surgical treatment in the Department of Thoracic Surgery, the First Affiliated Hospital of Nanjing Medical University, from November 2022 to June 2024. All patients underwent DECT perfusion imaging and pulmonary function testing (PFT) before surgery. PFT observation indicators included ventilation function indicators such as forced expiratory volume in one second (FEV1), forced vital capacity (FVC), 1-second rate (FEV1/FVC), maximal voluntary ventilation (MVV), and diffusion function indicators such as diffusing capacity for carbon monoxide (DLCO) and DLCO per liter of alveolar volume (DLCO/VA). The software eXamine was used to obtain quantitative parameters of DECT perfusion imaging, including volume parameters and perfusion parameters of both lungs and each lung lobe. The correlation between the volume parameters and perfusion parameters of both lungs and the ventilation and diffusion function indicators of the patients, as well as the differences in quantitative parameters of each lung lobe, was analyzed. Results The end-inspiration lung volume and biphasic volume difference were strongly positively correlated with FEV1 and FVC (r=0.636, r=0.682, r=0.614, r=0.624, P<0.001) and moderately positively correlated with MVV and DLCO (r=0.499, r=0.514, r=0.549, r=0.447, P<0.001); the end-expiration lung volume was weakly negatively correlated with DLCO/VA (r=−0.295, P=0.026); the volume ratio was positively correlated with FEV1, FVC, MVV, and MVV% (r=0.424, r=0.399, r=0.415, r=0.310, P<0.05); the end-inspiration iodine content was weakly positively correlated with DLCO/VA% (rs=0.292, P=0.030); the end-expiration iodine content was weakly positively correlated with FEV1, FVC, MVV, DLCO%, and DLCO/VA (r=0.307, r=0.299, r=0.295, r=0.366, r=0.320, P<0.05) and moderately positively correlated with DLCO (r=0.439, P<0.001); the end-inspiration iodine concentration was negatively correlated with FEV1, FVC, MVV, and MVV% (rs=−0.407, rs=−0.426, rs=−0.352, rs=−0.277, P＜0.05); the end-expiratory phase iodine concentration was moderately positively correlated with DLCO/VA (r=0.403, P=0.002); both the iodine concentration difference and the iodine concentration ratio were moderately positively correlated with FEV1, FEV1%, FVC, MVV, MVV% (P<0.05). The lung volume and iodine concentration ratio values were both highest in the left upper lung lobe and lowest in the right middle lung lobe; the differences in lung volume, lung volume ratio, intrapulmonary iodine content, and intrapulmonary iodine concentration were all highest in the lower lobes of both lungs and lowest in the middle lobe of the right lung. Conclusion Dual-phase DECT perfusion imaging can accurately assess overall lung function and quantify regional lung function.

Objective: To evaluate the effects of different surface treatment methods and simulated aging on the roughness, microhardness, and color stability of lithium disilicate glass ceramics(LDC). Methods: The LDC were grouped and performed 5 kinds of surface treatments: control group, polishing group, polishing+polishing paste group, glazing group, polishing+glazing group. The roughness and microhardness of the specimen were measured. Then the specimens were divided into two subgroupswhich were treated with water and staining solution. The specimens were measured color parameters before and after processing. The above data was analyzed. Results: The LDC had changes in surface roughness and microhardness after different surface treatments. The polishing+polishing paste group had the lowest surface roughness, and the surface microhardness of the LDC decreased after glazing. After simulating aging, the difference of color and transparency of the polishing+polishing paste group, glazing group, and polishing+glazing group were the smallest. Conclusion Different surface treatments and simulated aging have a certain impact on the roughness, microhardness, and color stability of LDC. Fine polishing with polishing paste has a comparable anti staining effect to glazing on LDC.

Objective To investigate the differences and the immunocompatibility of wild-type (WT), four-gene modified (TKO/hCD55) and six-gene modified (TKO/hCD55/hCD46/hTBM) pig erythrocytes with human serum. Methods The blood samples were collected from 20 volunteers with different blood groups. WT, TKO/hCD55, TKO/hCD55/hCD46/hTBM pig erythrocytes, ABO-compatible (ABO-C) and ABO-incompatible (ABO-I) human erythrocytes were exposed to human serum of different blood groups, respectively. The blood agglutination and antigen-antibody binding levels (IgG, IgM) and complement-dependent cytotoxicity were detected. The immunocompatibility of two types of genetically modified pig erythrocytes with human serum was evaluated. Results No significant blood agglutination was observed in the ABO-C group. The blood agglutination levels in the WT and ABO-I groups were higher than those in the TKO/hCD55 and TKO/hCD55/hCD46/hTBM groups (all P<0.001). The level of erythrocyte lysis in the WT group was higher than those in the ABO-C, TKO/hCD55 and TKO/hCD55/hCD46/hTBM groups. The level of erythrocyte lysis in the ABO-I group was higher than those in the TKO/hCD55 and TKO/hCD55/hCD46/hTBM groups (both P<0.01). The pig erythrocyte binding level with IgM and IgG in the TKO/hCD55 group was lower than those in the WT and ABO-I groups. The pig erythrocyte binding level with IgG and IgM in the TKO/hCD55/hCD46/hTBM group was lower than that in the WT group and pig erythrocyte binding level with IgG was lower than that in the ABO-I group (all P<0.05). Conclusions The immunocompatibility of genetically modified pig erythrocytes is better than that of wild-type pigs and close to that of ABO-C pigs. Humanized pig erythrocytes may be considered as a blood source when blood sources are extremely scarce.

Objective To summarize the experience and practical value of living donor kidney harvesting in Bama miniature pigs with six gene modified. Methods The left kidney of Bama miniature pigs with six gene modified was obtained by living donor kidney harvesting technique. First, the ureter was occluded, and then the inferior vena cava and abdominal aorta were freed. During the harvesting process, the ureter, renal vein and renal artery were exposed and freed in sequence. The vascular forceps were used at the abdominal aorta and inferior vena cava, and the renal artery and vein were immediately perfused with 4℃ renal preservation solution, and stored in ice normal saline for subsequent transplantation. Simultaneously, the donor abdominal aorta and inferior vena cava gap were sutured. The operation time, blood loss, warm and cold ischemia time, postoperative complications and the survival of donors and recipients were recorded. Results The left kidney of the genetically modified pig was successfully harvested. Intraoperative bleeding was 5 mL, warm ischemia time was 45 s, and cold ischemia time was 2.5 h. Neither donor nor recipient pig received blood transfusion, and urinary function of the kidney transplanted into the recipient was recovered. The donor survived for more than 8 months after the left kidney was resected. Conclusions Living donor kidney harvesting is safe and reliable in genetically modified pigs. Branch blood vessels could be processed during kidney harvesting, which shortens the process of kidney repair and the time of cold ischemia. Living donor kidney harvesting contributes to subsequent survival of donors and other scientific researches.

Objective To evaluate the preservation effect of normothermic mechanical perfusion with red blood cells from humanized genetically modified pig on severed human limbs.Methods Severed human limbs were perfused with red blood cells from humanized genetically modified pigs for 6 h.Perfusion solution was taken every hour to measure the oxygen partial pressure,Na+,K+,Ca2+,pH value,glucose,lactic acid and creatine kinase levels.Superficial flexor muscle was sampled to detect the changes of tumor necrosis factor(TNF)-α,interleukin(IL)-2 and IL-1 levels.At 0 and 6 h after perfusion,the superficial flexor muscles of the forearm were taken for pathological examination.Intercellular space and glycogen consumption of skeletal muscles were observed.An appropriate amount of forearm vessels was collected every 2 h to detect the apoptosis of vascular endothelial cells.X-ray angiography was performed before perfusion and 6 h after perfusion to observe the filling degree of finger-tip peripheral vessels.Results The oxygen partial pressure was observed in the normal range throughout the perfusion.Na+concentration peaked at 1 h,reaching 138.7 mmol/L,and then fluctuated within the normal range.K+level peaked at 2 h up to 6.08 mmol/L,then decreased and fluctuated within the normal range.Ca2+concentration reached the peak at 4 h,up to 1.03 mmol/L.Glucose level was gradually decreased at the beginning of perfusion,reaching the lowest value of 17.7 mmol/L at 2 h after perfusion,and then maintained a dynamic balance.The pH value was decreased to 7.28 at 6 h after perfusion.The lactic acid level was increased to 9.6 mmol/L at 1 h after perfusion,and then gradually decreased.The creatine kinase level was increased at the start of perfusion,reached the peak at 2 h up to 20 030 U/L,then decreased and remained stable at the end of perfusion.At the end of perfusion,the morphology of muscle fibers was normal,the gap among muscle fibers was expanded slightly,and the glycogen of skeletal muscles was not significantly accumulated.At 0 h perfusion,the number of apoptotic cells in vascular endothelial cells was large,which was declined at 6 h perfusion.Evident vascular filling was observed at 0 h,and the filling degree of some finger-tip vessels was decreased at 6 h.Conclusions Normothermic mechanical perfusion of severed human limbs with red blood cells from humanized genetically modified pigs may continuously and stably supply energy and oxygen,adjust the ion pH balance of perfusion solution,maintain normal cellular metabolism and exerts certain protective effect upon severed human limbs.

Limb dismemberment injuries are common in clinical practice,and safe and effective protection of the dismembered limb is the key to successful limb replantation.Normothermic machine perfusion has made significant breakthrough in the field of organ transplantation,which may maintain the active function of organs and tissues for a long period of time and prolong the preservation time.These findings have been validated in large animal models and clinical trials.Meantime,this technology is expected to provide novel reference for the preservation and functional recovery of severed limbs.Therefore,this paper reviews the problems of static cold preservation in the preservation of disarticulated limbs,the development history of mechanical perfusion,the current status of clinical application of ambient mechanical perfusion of disarticulated limbs as well as the problems to be solved,and looks forward to the direction of its development and the prospect of its clinical application,with a view to promoting the wide application of this technology in the clinic.

Objective:To understand the infection status and molecular types of rhinovirus (RV) among cases of Acute Respiratory Infections (ARIs) in Luohe City, Henan Province, from 2017 to 2022.Methods:From October 2017 to June 2022, clinical and epidemiological data were collected from 2 270 cases of ARIs at Luohe Central Hospital in Henan Province. Throat swab specimens were obtained from these cases. Real-time quantitative polymerase chain reaction (qPCR) was used to screen for RV-positive specimens. Subsequently, the positive samples were subjected to nested reverse transcription polymerase chain reaction (nested RT-PCR) to amplify the full-length VP1 region. Using the MEGA software, along with 169 RV reference strains recommended by the International Committee on Taxonomy of Viruses, a phylogenetic tree was constructed to determine RV types.Results:Among the 2 270 cases of ARIs, there were 1 283 male cases (56.52%). The median age ( Q 1, Q 3) was 3 (1, 6) years, with the population under 5 years old accounting for 68.59% (1 557/2 270). RV was detected in 137 cases (6.04%), of which 68 cases (49.64%) showed co-detection with other viruses, with the most common being co-detection with enterovirus, accounting for 14.60% (20/137). The RV detection rates in the age groups of 0-4 years, 5-14 years, 15-59 years, and≥60 years were 6.42% (100/1 557), 4.69% (21/448), 3.80% (6/158), and 9.35% (10/107), respectively, with no statistically significant differences ( χ2=5.310, P=0.150). The overall detection rates of RV before (2017-2019) and during (2020-2022) the COVID-19 pandemic showed no statistically significant difference ( χ2=1.823, P=0.177). A total of 109 VP1 sequences were obtained, including 62 types. Among them, RV-A, RV-B, and RV-C had 42, 3, and 17 types respectively. Conclusion:RV is one of the predominant pathogens in ARIs cases in Luohe City, Henan Province, from 2017 to 2022. Multiple types of RV co-circulate without any apparent dominant type.

Objective:To understand the epidemiological characteristics of human respiratory syncytial virus (HRSV) among acute respiratory infection (ARI) cases in 16 provinces of China from 2009 to 2023.Methods:The data of this study were collected from the ARI surveillance data from 16 provinces in China from 2009 to 2023, with a total of 28 278 ARI cases included in the study. The clinical specimens from ARI cases were screened for HRSV nucleic acid from 2009 to 2023, and differences in virus detection rates among cases of different age groups, regions, and months were analyzed.Results:A total of 28 278 ARI cases were enrolled from January 2009 to September 2023. The age of the cases ranged from<1 month to 112 years, and the age M ( Q1, Q3) was 3 years (1 year, 9 years). Among them, 3 062 cases were positive for HRSV nucleic acid, with a total detection rate of 10.83%. From 2009 to 2019, the detection rate of HRSV was 9.33%, and the virus was mainly prevalent in winter and spring. During the Corona Virus Disease 2019 (COVID-19) pandemic, the detection rate of HRSV fluctuated between 6.32% and 18.67%. There was no traditional winter epidemic peak of HRSV from the end of 2022 to the beginning of 2023, and an anti-seasonal epidemic of HRSV occurred from April to May 2023. About 87.95% (2 693/3 062) of positive cases were children under 5 years old, and the difference in the detection rate of HRSV among different age groups was statistically significant ( P<0.001), showing a decreasing trend of HRSV detection rate with the increase of age ( P<0.001). Among them, the HRSV detection rate (25.69%) was highest in children under 6 months. Compared with 2009-2019, the ranking of HRSV detection rates in different age groups changed from high to low between 2020 and 2023, with the age M (Q1, Q3) of HRSV positive cases increasing from 1 year (6 months, 3 years) to 2 years (11 months, 3 years). Conclusion:Through 15 years of continuous HRSV surveillance analysis, children under 5 years old, especially infants under 6 months old, are the main high-risk population for HRSV infection. During the COVID-19 pandemic, the prevalence and patterns of HRSV in China have changed.

Objective:To discuss the effect of long-term use of chlorhexidine on the resistance of Enterococcus faecalis(E.faecalis),and to clarify its mechanism.Methods:The standard strain of E.faecalis was repeatedly exposed to chlorhexidine for 10 generations,and the minimum inhibitory concentration(MIC)was recorded at each passage.The bacteria collected from the 10th generation with increased MIC values were designated as the E.faecalis chlorhexidine-resistant strains(E.faecalis-Cs).The growth curves of two strains were drawn;the morphology of two strains were observed by transmission electron microscope;the number of biofilm formation of two strains was detected by crystal violet staining;the bacterial hydrophobicities of two strains were detected by microbial adhesion to hydrocarbons(MATH)method;the expression levels of S-ribosylhomocysteine lyase(LuxS)mRNA in the bacterial biofilms of two strains were detected by real-time fluorescence quantitative PCR(RT-qPCR)method.Results:From the 0th to the 10th generation,the MIC values of E.faecalis were gradually increased.The growth curves of E.faecalis and E.faecalis-Cs showed no significant differences.The transmission electron microscope observation results showed that both E.faecalis and E.faecalis-Cs appeared oval or diplococcal,with intact cell wall structures,smooth edges,and evenly distributed cytoplasm.There were no significant differences in the morphology,size,cell wall thickness,or integrity between two types of bacteria.The crystal violet staining results showed that compared with E.faecalis,the number of biofilm formation of E.faecalis-Cs was significantly increased(P<0.05).The MATH results showed tha the hydrophobicity of E.faecalis-Cs was significantly higher than that of E.faecalis(P<0.05).The RT-qPCR results showed that the expression level of LuxS mRNA in the biofilms of E.faecalis-Cs was significantly higher than that of E.faecalis(P<0.05).Conclusion:E.faecalis develops the resistance after repeated exposure to the chlorhexidine,and the pathogenicity of the resistant strain is enhanced.The high expressin of quorum sensing(QS)system LuxS gene and stronger biofilm forming ability of bacteria may be the potential mechanism for E.faecalis to tolerate the chlorhexidine.

Objective:To analyze the root canal diameter of the mandibular first premolar by using finite element analysis to simulate the stress distribution of dentin under three different preparation methods,and to provide the basis for clinical root canal preparation strategies of the mandibular first premolars.Methods:Twenty-one patients with complete cone beam computed tomography(CBCT)images were selected.The original DICOM format data from CBCT were imported into Mimics 21.0 software to measure the root canal diameter at 3,6,9,and 12 mm from the apex and the root canal taper was segmentally calculated.Based on this,three-dimensional finite element models of the dental and periodontal tissues were constructed.Control group,maximum diameter preparation group,uniform preparation group,and 0.06 taper instrument preparation group were designed.In ANSYS Workbench 17.0 finite element analysis software,a 200 N load was applied to the buccal,lingual,and occlusal surfaces in various groups,and the stresses on dentin in various groups were analyzed.Results:The analysis of root canal taper at 3-6 mm,6-9 mm,and 9-12 mm from the apex of mandibular first premolar teeth showed that the taper was similar in the mesial-distal direction at 3-6 mm from the apex.The average taper in the buccal-lingual direction at 6-9 mm from the apex was 0.29,which was greater than the taper in the apical 1/3 and coronal 1/3.Under the same load,the peak stress values in dentin of mandibular first premolar teech in various groups were increased sequentially:4.693 6,16.304 0,14.278 0,and 18.682 0 MPa.The stress in maximum diameter preparation group concentrated on the canal wall with the highest stress value.The stress in uniform preparation group concentrated on the root surface,and the stress values on each section were lower than those in maximum diameter preparation group.The stress in 0.06 taper instrument preparation group concentrated on the apical 1/3 of the root surface.Conclusion:The root canal of the mandibular first premolar has a unique elliptical taper shape,and there are significant differences in diameter and taper between the mesial-distal and buccal-lingual directions.Different preparation methods result in different stress distributions on the canal wall,and the uniform preparation is the best method for enlarging the canal.