OBJECTIVE To investigate the feasibility and application of enzyme-linked bridging assay(ELBA)method to the pharmacokinetic evaluation of antisense strand siRNA drug. METHODS Antisense strand RNAs were diluted in LNCap cell lysates from 5 to 50 000 pmol·L-1 to construct the quantification curves. We transfected the intact double-strand siRNA at a final concentration 100 nmol·L-1 targeting Polo-like kinase into the LNCap cells and investigated the specificity of ELBA quantitating the siRNA antisense strand in cell supernatant,cell lysates and RNA-induced silencing complex( RlSC). Quantification curves were constructed and validated in biological matrices such as plasma (5-25 000 pmol·L-1 )and multiple tissues(liver,heart,spleen,and kidneys)(3-6250 pmol·L-1 ). The prostate specific membrane antigen aptamer siRNA delivery system with the intact siRNA concentration of 15 nmol·kg-1 was prepared. The siRNAs were delivered into the LNCap xenogrant tumor model in C57 mice by tail vein injection. The concentration of siRNA antisense strand was determined in plasma and tissues 30 min post administration by ELBA. RESULTS The quantitative range of antisense strand siRNA in cell lysates was 5-50 000 pmol·L-1 ,and ELBA method could quantify the siRNA antisense strand concentration from cell lysates and RlSC in LNCap cells transfected with double-strand siRNA. ln addition,ELBA could specifically reflect the single antisense strand concentration instead of intact siRNA double strands in plasma. The quantification range of siRNA antisense strand using ELBA in plasma was 5-25 000 pmol·L-1 and 3-3125 pmol·L-1 in tissues. About 30 min post administration of PSMA aptamer-siRNA,the antisense strand of siRNA was distributed mainly to the tumor,liver,kidneys,blood and spleen in sequence. The distribution profile might be attributed to the target delivery and siRNA pharma-codynamics. CONCLUSION The ELBA method is successfully applied to the siRNA antisense strand pharmacokinetic evaluation,which provides an alternative for pharmacokinetic studies of siRNA-based drugs.

Objective:To explore the pattern of pulmonary vascular remodeling in patients with chronic obstructive pulmonary disease (COPD) using artificial intelligence technology based on chest CT images.Methods:This was a cross-sectional study. The clinical and imaging data of 257 patients with stable COPD who underwent chest high resolution CT (HRCT) and pulmonary function tests (PFT) from January 2018 to October 2022 at Shanxi Bethune Hospital were retrospectively analyzed. In addition, 28 healthy individuals with normal HRCT and PFT were collected in the same period as a control group. According to the Global Initiative for Chronic Obstructive Lung Disease (GOLD) grading criteria, COPD patients were classified into 31 cases of GOLD 1, 116 cases of GOLD 2, 82 cases of GOLD 3, and 28 cases of GOLD 4. FACT digital lung software was used to automatically segment the pulmonary arteries and pulmonary veins of all the cases, and to calculate the relevant pulmonary vascular parameters, including total lung volume (TLV), vessel volumes at all levels [cross-sectional area less than 5 mm 2 (CSA <5), between 5 and 10 mm 2 (CSA 5-10), and more than 10 mm 2 (CSA >10)], number of vascular branches, and vascular density (pulmonary vascular volume/TLV). Percentage of emphysema (%LAA) and pulmonary artery diameter/aortic diameter (PAD/AD) were calculated for all cases. ANOVA or Kruskal-Wallis H test was used for multiple intergroup comparisons, and LSD test or Bonferroni correction was used for within-group pairwise comparisons. Spearman correlation test was conducted to examine the relationship between CT pulmonary vascular parameters and pulmonary function parameters, as well as %LAA, in both the control group and the COPD group. Results:Differences in age, body mass index, pulmonary function parameters, %LAA and PAD/AD were statistically significant among the 5 groups ( P<0.001). Differences in overall pulmonary vascular density parameters were statistically significant among the 5 groups ( P<0.05). Differences in pulmonary arterial density parameters among the 5 groups with CSA <5, CSA 5-10, and CSA >10 were statistically significant ( P<0.05). The pulmonary arterial density values of GOLD 1 CSA <5, CSA 5-10 and CSA >10 were higher than those of the control group, and then showed a decreasing trend with the increase of COPD severity. The differences in pulmonary venous density parameters among the 5 groups with CSA< 5, CSA 5-10, and CSA >10 were statistically significant ( P<0.001), and the CSA 5-10 pulmonary venous density was higher in GOLD 1 patients than in the control group, and the remaining pulmonary venous densities showed a gradual decreasing trend with the increase in the severity of COPD. The number of arterial and venous vascular branches/TLV tended to decrease in the control group, GOLD 1, GOLD 2, GOLD 3, and GOLD 4 patients ( P<0.001). Pulmonary vascular density parameters were positively correlated with all PFT parameters ( r=0.138-0.510, P<0.05), and negatively correlated with %LAA ( r=-0.340--0.671, P<0.001); PAD/AD was negatively correlated with PFT parameters ( r=-0.208--0.286, P<0.001) and positively correlated with %LAA ( r=0.131, P<0.05). Conclusion:Various pulmonary vascular density parameters can be quantitatively analyzed by artificial intelligence technology based on chest CT images, which can reveal the changing pattern of pulmonary vascular remodeling in COPD patients.

Objective:To investigate the protective effect of hypothermic antegrade machine perfusion against canine ischemic brain injury.Methods:Thirteen beagle dogs were divided into the mild hypothermia with perfusion group ( n=6) and normothermia with perfusion group ( n=7) according to the random number table. The model of ischemic brain injury was established by neck transection. After 1 hour of ischemic circulatory arrest, the perfusion fluid based on autologous blood was continuously perfused through bilateral common carotid artery for 6 hours. The temperature of the perfusion fluid was set at 33 ℃ in the mild hypothermia with perfusion group and 37℃ in the normothermia with perfusion group, respectively. Blood oxygen saturation was recorded at 0, 1, 2, 3, 4, 5 and 6 hours after the beginning of perfusion to evaluate the perfusate oxygen level. The perfusate was collected, and the levels of Na +, K +, Ca 2+ and glucose as well as the pH value of the perfusate were detected in the two groups. At the end of perfusion, the parietal brain tissues of 1 dog from each group were collected to evaluate the water contents of brain tissues. Nissl staining was used to evaluate the morphological integrity of the pyramidal neurons in the frontal cortex and hippocampus. Neuronal nuclei antigen (NeuN) was used to evaluate the structural and morphological integrity of pyramidal neurons. Immunofluorescence glial fibrillary acidic protein (GFAP) and ionic calcium binding adaptor molecule 1 (Iba1) were used to evaluate the integrity and activity of astrocytes and microglia fragments. Results:At 0, 1, 2, 3, 4, 5 and 6 hours of perfusion, there was no significant difference in the blood oxygen saturation or Na + concentrations between the two groups (all P>0.05); the K + concentrations in the mild hypothermia with perfusion group were (4.57±0.12)mmol/L, (4.67±0.14)mmol/L, (4.27±0.12)mmol/L, (4.45±0.10)mmol/L, (6.60±0.15)mmol/L, (7.37±0.18)mmol/L and (9.03±0.16)mmol/L, respectively, which were significantly lower than those in the normothermia with perfusion group [(4.84±0.10)mmol/L, (5.31±0.13)mmol/L, (5.44±0.24)mmol/L, (5.70±0.18)mmol/L, (7.79±0.18)mmol/L, (10.44±0.40)mmol/L, (10.40±0.41)mmol/L] (all P<0.01). At 0, 1, 2 and 3 hours of perfusion, the Ca 2+ concentrations in the mild hypothermia with perfusion group were (0.72±0.15)mmol/L, (1.55±0.16)mmol/L, (1.62±0.15)mmol/L and (1.88±0.15)mmol/L, respectively, being significantly higher than those in the normothermia with perfusion group [(0.41±0.13)mmol/L, (0.99±0.12)mmol/L, (1.29±0.13)mmol/L, (1.57±0.11)mmol/L] (all P<0.01), and no significant differences were found at other time points (all P>0.05). At 0, 1 and 2 hours of perfusion, the glucose concentrations in the mild hypothermia with perfusion group were (5.75±0.19)mmol/L, (5.17±0.15)mmol/L and (4.72±0.15)mmol/L, respectively, being significantly higher than those in the normothermia with perfusion group [(5.30±0.22)mmol/L, (4.89±0.20)mmol/L, (4.30±0.17)mmol/L] (all P<0.01), with no significant differences found at other time points (all P>0.05). At 2, 3, 4, 5 and 6 hours of perfusion, the pH values of the mild hypothermia with perfusion group were 7.32±0.06, 7.25±0.02, 7.23±0.02, 7.24±0.02 and 7.24±0.02, respectively, being significantly higher than those in the normothermia with perfusion group (7.26±0.01, 7.21±0.01, 7.17±0.02, 7.15±0.02, 7.08±0.02) ( P<0.05 or 0.01), with no significant differences at other time points (all P>0.05). The water content of brain tissues in the mild hypothermia with perfusion group was (74.9±0.4)%, which was significantly lower than (79.9±0.9)% in the normothermia with perfusion group ( P<0.01). Nissl staining showed that the pyramidal neurons in prefrontal cortex and dentate gyrus had good integrity in the mild hypothermia with perfusion group. NeuN immunofluorescence staining showed that the morphology and structure of pyramidal neuron cells in the mild hypothermia with perfusion group were better with clearly visible axons than those in the normothermia with perfusion group, whereas the cytosol was full and swollen with scarce axons in the normothermia with perfusion group. GFAP and Iba1 immunofluorescence staining showed that more structurally intact glial cells, more abnormally active cells, thickener axons and better axon integrity in all directions were found in the mild hypothermia with perfusion group than those in the normothermia with perfusion group. Conclusion:Compared with normal temperature antegrade mechanical perfusion, the mild hypothermia antegrade mechanical perfusion can protect canine brain tissue and alleviate ischemic brain injury by maintaining stable energy and oxygen supply, balancing ion homeostasis and perfusion fluid pH value, reducing tissue edema, and maintaining low metabolism of pyramidal neurons, astrocytes and microglia.

Objective To investigate the establishment of a six-gene-edited pig-to-non-human primate kidney xenotransplantation model. Methods The kidney of humanized genetically-edited pig (GTKO/β4GalNT2KO/CMAHKO/hCD55/hCD46/hTBM) was transplanted into a cynomolgus monkey. The survival of the recipient and kidney condition after blood perfusion were observed. The parenchymal echo, blood flow changes, and size of the kidney were monitored on a regular basis. Routine blood test, kidney function test and electrolyte assessment were carried out. Dynamic changes of urine, feces and body mass were monitored. At the end of life, the transplant kidney, heart, liver, spleen, lung, and cecum were collected for pathological examination. Results The recipient died at postoperative 7 d. After blood flow was restored, the kidney was properly perfused, the organ was soft and the color was normal. At the end of the recipient's life, a slight amount of purulent secretion was attached to the ventral side of the kidney, with evident congestion and swelling, showing the appearance of "red kidney". Postoperatively, the echo of renal parenchyma was increased, blood flow was decreased, the cortex was gradually thickened, and a slight amount of effusion surrounded the kidney and abdominal cavity over time. In the recipient, the amount of peripheral red blood cells, hemoglobin, albumin, and platelets was progressively decreased, and serum creatinine level was increased to 308 μmol/L at postoperative 7 d, whereas the K⁺ concentration did not significantly change. Light yellow urine was discharged immediately after surgery, diet and drinking water were resumed within postoperative 3 h, and light yellow and normal-shape stool was discharged. The reddish urine was gradually restored to normal color within postoperative 1 d, which were consistent with the results of the routine urine test. A large amount of brown bloody stool was discharged twice in the morning of 2 d after surgery. Omeprazole was given for acid suppression, and the stool returned to normal at postoperative 4 d. The β₂-microglobulin level was increased to 0.75 mg/L at postoperative 7 d. The body mass was increased by 1.7 kg. Autopsy pathological examination showed interstitial edema and bleeding of the transplant kidney, a large amount of infiltration of lymphocytes and macrophages, infiltration of lymphocytes in the arteriole wall and arterial cavity, accompanied by arteritis changes, lymphocyte infiltration in the cecal stroma and congestion in the spleen tissues. No significant abnormal changes were observed in other organs. Conclusions The humanized genetically-edited pig-to-non-human primate kidney xenotransplantation model is successfully established, and postoperative survival of the recipient is 1 week.

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 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.

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.

Although blood banks based on human blood can provide blood transfusions for the wounded timely and effec-tively,scientific research has never given up on finding new blood sources due to the restrictions of human blood sources.With the application of transgenic technology and the successful breeding of gene-edited pigs,gene-edited pig blood as a po-tential source of clinical transfusion has attracted wide attention.Now there are preclinical studies showing the feasibility of transfusing gene-edited pig red blood cells into primates.This paper discusses the related research and future development of xenogeneic transfusion of porcine red blood cells by gene editing.

BACKGROUND: Management of gastric leak after sleeve gastrectomy (SG) is challenging due to its unpredictable outcomes. We aimed to summarize the characteristics of SG leaks and analyze interventions and corresponding outcomes in a real-world setting. METHODS: To retrospectively review of 15,721 SG procedures from 2010 to 2020 based on a national registry. A cumulative sum analysis was used to identify a fitting curve of gastric leak rate. The Kaplan-Meier method and log-rank tests were performed to calculate and compare the probabilities of relevant outcomes. The logistic regression analysis was conducted to determine the predictors of acute leaks. RESULTS: A total of 78 cases of SG leaks were collected with an incidence of 0.5% (78/15,721) from this registry (6 patients who had the primary SG in non-participating centers). After accumulating 260 cases in a bariatric surgery center, the leak rate decreased to a stably low value of under 1.17%. The significant differences presented in sex, waist circumference, and the proportion of hypoproteinemia and type 2 diabetes at baseline between patients with SG leak and the whole registry population ( P = 0.005, = 0.026, <0.001, and = 0.001, respectively). Moreover, 83.1% (59/71) of the leakage was near the esophagogastric junction region. Leakage healed in 64 (88.9%, 64/72) patients. The median healing time of acute and non-acute leaks was 5.93 months and 8.12 months, respectively. Acute leak (38/72, 52.8%) was the predominant type with a cumulative reoperation rate >50%, whereas the cumulative healing probability in the patients who required surgical treatment was significantly lower than those requring non-surgical treatment ( P = 0.013). Precise dissection in the His angle area was independently associated with a lower acute leak rate, whereas preservation ≥2 cm distance from the His angle area was an independent risk factor. CONCLUSIONS Male sex, elevated waist circumference, hypoproteinaemia, and type 2 diabetes are risk factors of gastric leaks after SG. Optimizing surgical techniques, including precise dissection of His angle area and preservation of smaller gastric fundus, should be suggested to prevent acute leaks.
Humans ; Male ; Retrospective Studies ; Diabetes Mellitus, Type 2/complications* ; Obesity, Morbid ; Anastomotic Leak/epidemiology* ; Gastrectomy/methods* ; Reoperation/methods* ; Registries ; Laparoscopy/methods* ; Treatment Outcome

Abdomen/diagnostic imaging* ; Artificial Intelligence ; Body Composition ; Magnetic Resonance Imaging ; Practice Guidelines as Topic