Proliferation and metabolic patterns of smooth muscle cells during construction of tissue-engineered blood vessels / 中国组织工程研究

BACKGROUND:Seed cells are seeded on three-dimensional scaffold materials,and three-dimensional culture in bioreactors is a common in vitro tissue engineering culture method,but the changes in cell proliferation and metabolic patterns in bioengineered blood vessel construction are still unclear. OBJECTIVE:To explore the metabolic changes of cells such as oxygen consumption and their causes during the whole process of biological vascular tissue construction by in vitro bioreactor. METHODS:The self-built vascular bioreactor system was used as the platform;bovine vascular smooth muscle cells were used as the seed cells,and a conventional CO2 incubator provided the external gas environment for the cultivation process.Seed cells were seeded on a tubular porous polyglycolic acid scaffold material for three-dimensional culture,and the whole process included a one-week resting period and a seven-week pulsating tensile stress stimulation loading period.A non-invasive monitoring system was built,and the optical dissolved oxygen patch method was used to monitor the changes of dissolved oxygen in the culture solution in the reactor,and the glucose consumption and lactic acid production were measured by regular sampling.CCK-8 assay was used to determine the proliferation of smooth muscle cells on polyglycolic acid three-dimensional scaffold materials.Nicotinamide adenine dinucleotide oxidation state and reduction state ratio(NAD+/NADH)was utilized to understand cell proliferation and metabolism in the early stage of culture.RT-qPCR and western blot assay were applied to detect the expression of proliferation-related genes(Ki67)and glycolysis-related genes(GLUT-1,LDHA). RESULTS AND CONCLUSION:(1)The dissolved oxygen level in the culture solution was(4.314±0.380)mg/L from the cell injection to the end of the resting period(the first week),and gradually stabilized at(1.960±0.866)mg/L after the tensile stress stimulation(the last seven weeks);the two had significant changes(P<0.05).(2)The ratio of glucose consumption to lactic acid production in the cell culture medium YL/G increased rapidly after the cells were injected,and the highest value was above 1 on the fifth day,and then slow down to 0.5(The mean value of YL/G in the resting period was 0.89 and the mean value in the pressurized period was 0.57,P<0.05).(3)CCK-8 assay results showed that A450 value gradually increased after the cells were injected,and reached the highest value on the fifth day,reaching 3.17,and then slowly decreased.At the same time,it was found that Ki67 mRNA was up-regulated on the third day of culture,and then declined.The expression level of Ki67 protein was higher from the third day to the fifth day.(4)The detection of NAD+/NADH showed that the increase was obvious from the fifth to the seventh day after the injection of cells,and the expression of glycolysis-related genes(GLUT-1 and LDHA)was up-regulated and changed synchronously,and the relative expression was higher in the first five days.(5)The results showed that the tissue-engineered blood vessels were constructed using the vascular bioreactor and the smooth muscle cells in the early stage mainly proliferated and exhibited a metabolic feature of low oxygen consumption.The metabolic characteristics of high oxygen consumption were observed during the pulsatile tensile stress stimulation stage.

Percutaneous transforaminal endoscopic discectomy combined with platelet-rich plasma in treatment of lumbar disc herniation / 中国组织工程研究

BACKGROUND:Platelet-rich plasma can promote the repair and regeneration of intervertebral disc tissue.Percutaneous transforaminal endoscopic discectomy is widely used in the treatment of lumbar disc herniation.In recent years,more and more scholars have focused on the combined treatment of lumbar disc herniation with the two techniques in order to achieve a better patient prognosis. OBJECTIVE:To investigate the clinical safety and effectiveness of percutaneous transforaminal endoscopic discectomy combined with platelet-rich plasma in the treatment of lumbar disc herniation. METHODS:The clinical data of 58 patients with lumbar disc herniation who met the inclusion and exclusion criteria at Sixth Medical Center of PLA General Hospital from June 2017 to May 2018 were retrospectively analyzed.Among them,29 patients underwent percutaneous transforaminal endoscopic discectomy combined with platelet-rich plasma(observation group),and the remaining 29 patients underwent percutaneous transforaminal endoscopic discectomy only(control group).Visual Analogue Scale score for back and leg pain,lumbar JOA score,and Oswestry Disability Index were evaluated preoperatively,at 3,6,and 12 months postoperatively,and at the last follow-up.Intervertebral space height,nucleus pulposus to cerebrospinal fluid signal strength ratio,and intervertebral disc Pfirrmann grading were measured preoperatively,at 6 and 12 months postoperatively,and at the last follow-up.The modified MacNab criteria were used to assess excellent and good rate of curative effect at the last follow-up. RESULTS AND CONCLUSION:(1)The Visual Analogue Scale score for back and leg pain,JOA score,and Oswestry Disability Index of the two groups postoperatively were significantly improved compared with those preoperatively(P<0.05).Visual Analogue Scale score and Oswestry Disability Index were lower in the observation group than those in the control group at 3 and 6 months postoperatively(P<0.05).The JOA score was higher in the observation group than that in the control group at 3 and 6 months postoperatively(P<0.05).(2)The nucleus pulposus to cerebrospinal fluid signal strength ratio was higher in the observation group than that in the control group at the last follow-up(P<0.05).Pfirrmann grading of the intervertebral discs was better in the observation group than that in the control group(P<0.05).The excellent and good rate was 93%in the observation group and 83%in the control group,and the difference was not statistically significant(P>0.05).(3)These findings indicate that percutaneous transforaminal endoscopic discectomy combined with platelet-rich plasma in the treatment of lumbar disc herniation has satisfactory clinical efficacy and can delay the degeneration of the intervertebral disc to a certain extent.

Mechanism by which interleukin-1beta regulates the expression of Semaphorin 3A to induce intervertebral disc degeneration / 中国组织工程研究

BACKGROUND:Semaphone 3A(Sema3A)is an important neurovascular growth inhibitor.It is not clear how Sema3A is involved in the pathogenesis of discogenic low back pain.Exploring the potential mechanism of Sema3A in intervertebral disc degeneration can provide a new target and theoretical basis for the prevention and treatment of discogenic low back pain. OBJECTIVE:To explore the mechanism of interleukin-1β inhibiting the expression of Sema3A by activating the nuclear factor-κB signaling pathway to induce intervertebral disc degeneration in rats. METHODS:RT-qPCR was used to detect the expression of Sema3A mRNA in normal and degenerative human nucleus pulposus tissues.Nucleus pulposus cells of Sprague-Dawley rats were isolated,cultured,and passaged to the 3rd generation.Then,passage 3 cells were divided into three groups:the blank control group was routinely cultured for 48 hours,the degeneration group was intervened with 10 ng/mL interleukin 1β for 48 hours,and the degeneration+inhibitor group was treated by 5 μmol/L nuclear factor-κB signaling pathway-specific inhibitor BAY11-7082 for 1 hour,followed by interleukin-1β for 48 hours.At the end of the intervention,cell viability was detected by cell counting kit-8,cell apoptosis was detected by Annexin V/FITC staining,mRNA expression of cellular matrix,vascular and neural markers and Sema3A was detected by RT-qPCR,and protein expression of marker proteins,p65 and p-p65 was detected by western blot. RESULTS AND CONCLUSION:RT-qPCR assay showed that the expression of Sema3A mRNA was lower in degenerative human nucleus pulposus tissue than in normal human nucleus pulposus tissue(P＜0.05).Compared with the blank control group,the nucleus pulposus cell viability decreased and the apoptotic rate increased in the degeneration group(P＜0.05);compared with the degeneration group,the nucleus pulposus cell viability increased and the apoptotic rate decreased in the degeneration + inhibitor group(P＜0.05).Compared with the blank control group,mRNA expression of type Ⅱ collagen,polyproteoglycan,and Sema3A was decreased in the degeneration group(P＜0.05),while mRNA expression of CD31 and neurofilament 200 was increased(P＜0.05).Compared with the degeneration group,mRNA expression of type Ⅱ collagen,polyproteoglycan,and Sema3A was elevated in the degeneration+inhibitor group(P＜0.05)and mRNA expression of CD31 and neurofilament 200 decreased(P＜0.05).Compared with the blank control group,the protein expression of type Ⅱ collagen,polyproteoglycan,and Sema3A was decreased in the degeneration group(P＜0.05),and the protein expression of CD31,neurofilament protein 200,p65,and p-p65 was elevated(P＜0.05);compared with the degeneration group,the protein expression of type Ⅱ collagen,polyproteoglycan,and Sema3A was elevated in the degeneration+inhibitor group(P＜0.05),and protein expression of CD31,neurofilament 200,p65,and p-p65 was decreased(P＜0.05).To conclude,interleukin-1β does inhibit the expression of Sema3A by activating the nuclear factor-κB signaling pathway,which can also increase the degradation of extracellular matrix,promote the innervation and angiogenesis in degenerative intervertebral disc,and may be one of potential factors that contribute to intervertebral disc degeneration and discogenic low back pain.

Finite element analysis of interspinous fixation-assisted endoscopic interbody fusion in treatment of severe lumbar spinal stenosis / 中国组织工程研究

BACKGROUND:In clinical application,simple interspinous fixation without additional interbody fusion has similar fixation effects to pedicle screw and rod fusion internal fixation,and can effectively reduce the range of motion of the responsible segment and the stress of the articular process.However,after simple placement of the new interspinous fusion fixation device BacFuse,the stress at the root of the spinous process is relatively concentrated,and the spinous fracture is prone to occur.If an intervertebral fusion cage is inserted in conjunction with interspinous fixation,Von Mises stress can theoretically be dispersed to reduce the risk of spinous fracture.However,there are few studies on biomechanics and finite element analysis. OBJECTIVE:To observe the biomechanical stability of interspinous fixation-assisted endoscopic interbody fusion in the treatment of severe lumbar spinal stenosis. METHODS:The normal finite element model M0 of the L4-L5 segment of the lumbar spine was established by Mimics,Geomagic,Solidworks,and ANSYS software based on the lumbar CT images of a 26-year-old adult male volunteer excluding spinal diseases.On the basis of M0,the immediate model M1 after endoscopic decompression combined with interbody fusion,the interspinous fixation device(BacFuse)model M2 after endoscopic decompression,and the interspinous fixation(BacFuse)model M3 after endoscopic-assisted interbody fusion were established.The same stress was applied to the upper surface of the L4 vertebral body in the four groups,and the lower surface of the L5 vertebral body was fixed and supported.The range of motion and the extreme Von Mises stress of the endplate bone and the posterior ligament complex of the vertebral body were analyzed under six working conditions of flexion,extension,left/right bending,and left/right rotation. RESULTS AND CONCLUSION:(1)Compared with model M0,the range of motion value of model M1 increased significantly under six working conditions.Model M2 and model M3 had a significant reduction in range of motion.(2)Compared with model M0,the maximum stress of the vertebral body in model M1 did not change significantly under the six working conditions.The maximum stress at the rear of the M2 vertebral body increased significantly.(3)Compared with model M1,the maximum stress of model M3 did not change significantly under the six working conditions.Compared with model M2,the maximum stress of model M3 decreased significantly.(4)Compared with the model M0,the extreme Von Mises stress of the L4 and L5 endplates of the model M1 was significantly increased.The extreme Von Mises stress in L4 and L5 endplates of models M2 and M3 decreased slightly.Compared with model M1,the Von Mises stress of the bone under the L4 and L5 endplate of models M2 and M3 was significantly reduced.(5)It is concluded that the implantation of BacFuse can effectively reduce the bone stress under the endplate during simple interbody fusion,decrease the risk of cage subsidence,diminish the risk of facet joint fracture on the decompression side,and provide a good stable environment for interbody fusion.The placement of an intervertebral fusion cage can reduce the stress of the root of the spinous process,which is beneficial to decrease the risk of fracture of the root of the spinous process.

Factors affecting osteoporosis among people aged 60 years and above / 预防医学

Objective@#To investigate the prevalence of osteoporosis (OP) and its influencing factors among people aged 60 years and above, so as to provide insights into OP prevention and treatment among the elderly.@*Methods@#People aged 60 years and above who underwent physical examinations were selected from Hangzhou First People's Hospital from January to October 2023. Demographic information, lifestyle and physical examination data were collected through field surveys and hospital information systems. Bone density was measured by dual-energy X-ray densitometer, and OP was diagnosed with reference to the Guidelines for the Diagnosis and Treatment of Primary Osteoporosis (2022). Factors affecting the OP were identified using a multivariable logistic regression model.@*Results@#A total of 482 participants were included and had a mean age of (69.10±6.52) years. There were 217 men (45.02%) and 265 women (54.98%). The prevalence of OP was 43.36%. Multivariable logistic regression analysis identified gender (women, OR=3.791, 95%CI: 1.726-8.314), age (70 to 79 years, OR=1.260, 95%CI: 1.018-1.559; 80 years and above, OR=3.083, 95%CI: 1.546-6.147), body mass index (≥24 kg/m2, OR=0.358, 95%CI: 0.205-0.626), family history of fracture (OR=1.475, 95%CI: 1.073-2.030), diabetes (OR=1.626, 95%CI: 1.109-2.382), regular exercise (OR=0.457, 95%CI: 0.287-0.726), intake of milk products (OR=0.511, 95%CI: 0.335-0.780), intake of calcium supplements (OR=0.473, 95%CI: 0.287-0.778) and vitamin D deficiency (OR=2.132, 95%CI: 1.309-3.473) as factors affecting OP.@*Conclusion@#The prevalence of OP is associated with gender, age, body mass index, family history of fracture, diabetes, diet and vitamin D deficiency.

Genome-wide analysis of AP2/ERF superfamily in Isatis indigotica / 中西医结合学报

OBJECTIVE@#AP2/ERF (APETALA2/ethylene-responsive factor) superfamily is one of the largest gene families in plants and has been reported to participate in various biological processes, such as the regulation of biosynthesis of active lignan. However, few studies have investigated the genome-wide role of the AP2/ERF superfamily in Isatis indigotica. This study establishes a complete picture of the AP2/ERF superfamily in I. indigotica and contributes valuable information for further functional characterization of IiAP2/ERF genes and supports further metabolic engineering.@*METHODS@#To identify the IiAP2/ERF superfamily genes, the AP2/ERF sequences from Arabidopsis thaliana and Brassica rapa were used as query sequences in the basic local alignment search tool. Bioinformatic analyses were conducted to investigate the protein structure, motif composition, chromosome location, phylogenetic relationship, and interaction network of the IiAP2/ERF superfamily genes. The accuracy of omics data was verified by quantitative polymerase chain reaction and heatmap analyses.@*RESULTS@#One hundred and twenty-six putative IiAP2/ERF genes in total were identified from the I. indigotica genome database in this study. By sequence alignment and phylogenetic analysis, the IiAP2/ERF genes were classified into 5 groups including AP2, ERF, DREB (dehydration-responsive element-binding factor), Soloist and RAV (related to abscisic acid insensitive 3/viviparous 1) subfamilies. Among which, 122 members were unevenly distributed across seven chromosomes. Sequence alignment showed that I. indigotica and A. thaliana had 30 pairs of orthologous genes, and we constructed their interaction network. The comprehensive analysis of gene expression pattern in different tissues suggested that these genes may play a significant role in organ growth and development of I. indigotica. Members that may regulate lignan biosynthesis in roots were also preliminarily identified. Ribonucleic acid sequencing analysis revealed that the expression of 76 IiAP2/ERF genes were up- or down-regulated under salt or drought treatment, among which, 33 IiAP2/ERF genes were regulated by both stresses.@*CONCLUSION@#This study undertook a genome-wide characterization of the AP2/ERF superfamily in I. indigotica, providing valuable information for further functional characterization of IiAP2/ERF genes and discovery of genetic targets for metabolic engineering.

Toxic Epidermal Necrolysis Induced by Sintilimab: A Case Report

Sintilimab is an anti-programmed cell death receptor-1 antibody. The phase III clinical trial ORIENT-12 confirmed the safety of sintilimab combined with pemetrexed/platinum in the treatment of advanced squamous non-small cell lung cancer. Skin reactions are the most commonly reported adverse events of immune checkpoint inhibitors and are rarely severe.We describe a case of toxic epidermal necrolysis related to sintilimab in an elderly oncologic patient. 3 weeks after immunotherapy, the patient developed an extensive rash and diffuse itching, rapidly evolving into macules, blisters, bullae and erosions. Causal evaluation was performed based on the algorithm of drug causality for epidermal necrolysis and national Food and Drug Administration qualitative analysis. The patient responded to high-dose glucocorticosteroid and supportive therapy, alongside with local wound care. If immune checkpoint inhibitors need to be extrapolated clinically, strictly following evidence-based research, promptly detecting and treating adverse reactions is crucial.

Wnt/b-Catenin Promotes the Osteoblastic Potential of BMP9 Through Down-Regulating Cyp26b1 in Mesenchymal Stem Cells

BACKGROUND@#All-trans retinoic acid (ATRA) promotes the osteogenic differentiation induced by bone morphogenetic protein 9 (BMP9), but the intrinsic relationship between BMP9 and ATRA keeps unknown. Herein, we investigated the effect of Cyp26b1, a critical enzyme of ATRA degradation, on the BMP9-induced osteogenic differentiation in mesenchymal stem cells (MSCs), and unveiled possible mechanism through which BMP9 regulates the expression of Cyp26b1. @*METHODS@#ATRA content was detected with ELISA and HPLC–MS/MS. PCR, Western blot, and histochemical staining were used to assay the osteogenic markers. Fetal limbs culture, cranial defect repair model, and micro–computed tomographic were used to evaluate the quality of bone formation. IP and ChIP assay were used to explore possible mechanism. @*RESULTS@#We found that the protein level of Cyp26b1 was increased with age, whereas the ATRA content decreased. The osteogenic markers induced by BMP9 were increased by inhibiting or silencing Cyp26b1 but reduced by exogenous Cyp26b1. The BMP9-induced bone formation was enhanced by inhibiting Cyp26b1. The cranial defect repair was promoted by BMP9, which was strengthened by silencing Cyp26b1 and reduced by exogenous Cyp26b1. Mechanically, Cyp26b1 was reduced by BMP9, which was enhanced by activating Wnt/b-catenin, and reduced by inhibiting this pathway. b-catenin interacts with Smad1/5/9, and both were recruited at the promoter of Cyp26b1. @*CONCLUSIONS@#Our findings suggested the BMP9-induced osteoblastic differentiation was mediated by activating retinoic acid signalling, viadown-regulating Cyp26b1. Meanwhile, Cyp26b1 may be a novel potential therapeutic target for the treatment of bone-related diseases or accelerating bone-tissue engineering.

Improving the understanding of PI-RADS in practice: characters of PI-RADS 4 and 5 lesions with negative biopsy / 亚洲男科学杂志(英文版)

The Prostate Imaging Reporting and Data System (PI-RADS) has good ability to identify the nature of lesions on prostate magnetic resonance imaging (MRI). However, some lesions are still reported as PI-RADS 4 and 5 but are biopsy-proven benign. Herein, we aimed to summarize the reasons for the negative prostate biopsy of patients who were assessed as PI-RADS 4 and 5 by biparameter MRI. We retrospectively sorted out the prostate MRI, treatment, and follow-up results of patients who underwent a biparameter MRI examination of the prostate in The First Affiliated Hospital of Nanjing Medical University (Nanjing, China) from August 2019 to June 2021 with PI-RADS 4 and 5 but a negative biopsy. We focused on reviewing the MRI characteristics. A total of 467 patients underwent transperineal prostate biopsy. Among them, biopsy pathology of 93 cases were negative. After follow-up, 90 patients were ruled out of prostate cancer. Among the 90 cases, 40 were considered to be overestimated PI-RADS after review. A total of 22 cases were transition zone (TZ) lesions with regular appearance and clear boundaries, and 3 cases were symmetrical lesions. Among 15 cases, the TZ nodules penetrated the peripheral zone (PZ) and were mistaken for the origin of PZ. A total of 17 cases of lesions were difficult to distinguish from prostate cancer. Among them, 5 cases were granulomatous inflammation (1 case of prostate tuberculosis). A total of 33 cases were ambiguous lesions, whose performance was between PI-RADS 3 and 4. In summary, the reasons for "false-positive MRI diagnosis" included PI-RADS overestimation, ambiguous images giving higher PI-RADS, diseases that were really difficult to distinguish, and missed lesion in the initial biopsy; and the first two accounted for the most.

Establishment of a prognostic nomogram model for predicting acute renal injury in patients with moderate and severe burns / 中华危重病急救医学

OBJECTIVE@#To establish a prediction model of acute kidney injury (AKI) in moderate and severe burn patients, so as to provide basic research evidence for early identification of burn-related AKI.@*METHODS@#Patients who were admitted to the department of plastic burn surgery of the Affiliated Hospital of Southwest Medical University from November 2018 to January 2021 were selected, and their clinical characteristics, laboratory examinations and other indicators were recorded. Multivariate Logistic regression analysis was used to screen out the risk factors of AKI related to moderate and severe burns, and R software was used to establish the nomogram of moderate and severe burn patients complicated with AKI. The Bootstrap method model was used for internal verification by repeating sample for 1 000 times. Consistency index and calibration curve were used to evaluate the accuracy of the model, and the receiver operator characteristic curve (ROC curve) and the area under the curve (AUC) were used to evaluate the prediction efficiency, decision curve analysis (DCA) was used to evaluate the clinical utility of the model.@*RESULTS@#A total of 186 patients with moderate and severe burn were included, among which 54 patients suffered from AKI, and the incidence rate was 29.03%. Multivariate Logistic regression analysis showed that the total burn surface area [TBSA; odds ratio (OR) = 1.072, 95% confidence interval (95%CI) was 1.031-1.115, P = 0.001], estimated glomerular filtration rate (eGFR; OR = 0.960, 95%CI was 0.931-0.990, P = 0.010), neutrophil (NEU; OR = 1.190, 95%CI was 1.021-1.386, P = 0.026), neutrophil/lymphocyte ratio (NLR; OR = 0.867, 95%CI was 0.770-0.977, P = 0.019), D-dimer (OR = 4.603, 95%CI was 1.792-11.822, P = 0.002) were the risk factors for patients with moderate and severe burn complicated with AKI. Taking the above indexes as predictive factors, a nomogram prediction model was established, the ROC curve was plotted with AUC of 0.998 (95%CI was 0.988-1.000). Optimum threshold of ROC curve was -0.862, the sensitivity was 98.0% and the specificity was 98.2%, and the consistency index was 0.998 (95%CI was 0.988-1.000). The calibration curve showed that the prognostic nomogram model was accurate, DCA showed that most patients can benefit from this model.@*CONCLUSIONS@#The burned patients with higher TBSA, NEU, NLR, D-dimer and lower eGFR tend to suffer from AKI. The nomogram based on the above five risk factors has high accuracy and clinical value, which can be used as a predictive tool to evaluate the risk of AKI in moderate and severe burn patients.

C2 pedicle screw insertion assisted by mobilization of the vertebral artery in cases with high-riding vertebral artery / 中华外科杂志

Objective: To examine the feasibility, safety, and efficacy of mobilization of the vertebral artery for C2 pedicle screws in cases with high-riding vertebral artery (HRVA). Methods: The clinical data of 12 patients with basilar invagination and atlantoaxial dislocation underwent atlantoaxial reduction and fixation in the Department of Neurosurgery, the First Affiliated Hospital of University of Science and Technology of China between January 2020 and November 2021 were retrospectively analyzed. All patients had high-riding vertebral artery on at least one side that prohibited the insertion of C2 pedicle screws. There were 2 males and 10 females aged (48.0±12.8) years (range: 17 to 67 years). After correction of vertical dislocation during the operation, the C2 pedicle screw insertion and occipitocervical fixation and fusion were performed using the vertebral artery mobilization technique. Neurological function was assessed using the Japanese Orthopedic Association (JOA) scale. The preoperative and postoperative JOA score and the main radiological measurements, including the anterior atlantodental interval (ADI), the distance of the odontoid tip above the Chamberlain line, the clivus-canal angle, were collected and compared by paired t-test. Results: Mobilization of the high-riding vertebral artery was successfully completed, and C2 pedicle screws were then fulfilled after the vertebral artery was protected. There was no injury to the vertebral artery during the operation. Meanwhile, no severe surgical complications such as cerebral infarction or aggravated neurological dysfunction occurred during the perioperative period. Satisfactory C2 pedicle screw placement and reduction were achieved in all 12 patients. All patients achieved bone fusion 6 months after surgery. No looseness and shift in internal fixation or reduction loss was observed during the follow-up period. Compared to the preoperative, the postoperative ADI decreased from (6.1±1.9) mm to (2.0±1.2) mm (t=6.73, P<0.01), the distance of the odontoid tip above the Chamberlain line decreased from (10.4±2.5) mm to (5.5±2.3) mm (t=7.12, P<0.01), the clivus-canal angle increased from (123.4±11.1) ° to (134.7±9.6) ° (t=2.50, P=0.032), the JOA score increased from 13.3±2.1 to 15.6±1.2 (t=6.99, P<0.01). Conclusion: The C2 pedicle screw insertion assisted by mobilization of the vertebral artery is safe and considerably effective, providing a choice for internal fixation in cases with high-riding vertebral arteries.

Factor analysis of secondary intraocular hypertension after intravitreal dexamethasone implantation in patients with diabetic macular edema / 中华眼底病杂志

Objective:To observe and analyze the risk factors of secondary intraocular hypertension in diabetic macular edema (DME) patients after treatment with dexamethasone vitreous cavity implant (DEX).Methods:A retrospective observational study. A total of 352 patients with type 2 diabetes mellitus (T2DM) secondary macular edema diagnosed by ophthalmic examination and treated with DEX in Department of Ophthalmology of Harbin 242 Hospital from January 2016 to March 2022 were included in the study. Among them, 221 were males and 131 were females, with the mean age of (55.56±8.09) years. There were 194 patients with disseminated macular edema, 158 patients with cystoid macular edema. All patients underwent vitreous cavity implantation of DEX. Intraocular pressure (IOP) was measured once a month for 3 months after treatment, with IOP over than 25 mm Hg (1 mm Hg=0.133 kPa) or higher than 10 mm Hg from baseline as secondary intraocular hypertension. The relevant clinical data were collected, and the risk factors of secondary intraocular hypertension in DME patients after DEX treatment were analyzed by binary logistic regression.Results:Among 352 patients, 116 patients (32.95%, 116/352) were in the intraocular hypertension. Among them, 29 patients (25.00%, 29/116), 69 patients (59.48%, 69/116) and 18 patients (15.52%, 18/116) occurred intraocular hypertension at 1, 2 and 3 months after treatment, respectively. Compared with the normal IOP group, the IOP in the intraocular hypertension group increased significantly at 1, 2 and 3 months after treatment, with statistical significance ( t=10.771, 21.116, 13.761; P<0.001). Compared with normal IOP group, the patients in the intraocular hypertension group had younger age ( t=6.967), longer duration of diabetes ( t=5.950), longer axial length (AL) ( t=14.989), higher proportion of DME grade 3 ( Z=6.284), higher proportion of DEX implantation in pars plana ( χ2=23.275), and higher HbA1c level ( t=10.764), the differences were statistically significant ( P<0.05). Logistic regression analysis showed that longer AL [odds ratio ( OR)=1.428, 95% confidence interval ( CI) 1.054-1.934], DEX implantation in pars plana ( OR=1.358, 95% CI 1.063-1.735), and higher HbA1c ( OR=1.702, 95% CI 1.225-2.366) were the risk factors for secondary intraocular hypertension in DME patients after DEX treatment ( P<0.05), older age was a protective factor ( OR=0.548, 95% CI 0.380-0.789, P<0.05). Conclusions:Long AL, DEX implantation in pars plana and high HbA1c are the risk factors for secondary intraocular hypertension after DEX treatment in DME patients, older age is a protective factor.

Effect of hypothermic machine perfusion on expression levels of inflammatory cytokines in rat kidney / 器官移植

Objective To evaluate the effect of hypothermic machine perfusion (HMP) on the expression levels of inflammatory cytokines in rat kidney. Methods Thirty male rats were randomly divided into the control (Control group), static cold storage group (SCS group) and HMP group, with 10 rats in each group. The velocity, intrarenal resistance and pH value of perfusion effluent were recorded during HMP. The expression levels of CXC chemokine ligand (CXCL)1, CXCL2, interferon (IFN)-β1, IFN-α4, CC chemokine ligand (CCL)2, CCL20, interleukin (IL)-17α, IL-17C and tumor necrosis factor (TNF)-α messenger RNA (mRNA) in renal tissues were evaluated by reverse transcription polymerase chain reaction (RT-PCR). Pathological changes of the kidney were observed by hematoxylin-eosin (HE) staining. Results During HMP, the velocity and intrarenal resistance remained stable, and the pH value of perfusion effluent was decreased slowly. RT-PCR showed that the relative expression levels of CXCL1, CXCL2, CCL2, CCL20, IL-17α, IL-17C and TNF-α mRNA in the SCS and HMP groups were higher compared with those in the Control group. Compared with the SCS group, the relative expression levels of CXCL1, CXCL2, CCL2, CCL20, IL-17α and TNF-α mRNA were up-regulated in the HMP group (all P<0.05). HE staining revealed that the morphology of renal cells was normal in the Control group, whereas evident epithelial necrosis, cytoplasmic vacuolation, brush border loss and epithelial shedding were observed in the SCS group. Compared with the SCS group, pathological changes in the HMP group were alleviated. Conclusions HMP may activate renal inflammation, and inhibiting the activation of inflammation during HMP is expected to further improve the effect of allograft preservation.

Pathogenic detection and molecular tracing of a bacillary dysentery outbreak by Shigella sonnei in Huainan city / 中华预防医学杂志

Objective: To understand the virulence gene and drug resistance profile of Shigella sonnei outbreak in Huainan city, and conduct pathogenic traceability analysis. Methods: Water samples and feces related to an infectious diarrhea outbreak in Huainan city in August 2020 were collected for multiple pathogen detection. Virulence gene, drug sensitivity, pulse-field gel electrophoresis and whole genome sequencing of Shigella isolates were analyzed respectively. Results: 38 strains of Shigella sonnei were detected in 56 samples of mucilage feces with a positive rate 67.86%, and all serotypes were Shigella sonnei Phase I. Three strains of Shigella sonnei were detected by fluorescence PCR in the Gram-negative (GN) bacterial enrichment solution of terminal water and well water. Virulence genes were ipaH positive (38), ipaH/ial (31) and ipaH/ial/sen positive (1), respectively. The drug resistance spectrum showed that 9 of 14 antibiotics were 100% resistant, and only imipenem, chloramphenicol, ceftazidime and ciprofloxacin were effective drugs. XbaⅠ restriction enzyme map type of 36 isolates was completely consistent, and the ST type analysis of 3 strains was ST152. Whole genome sequencing and analysis verified that the outbreak was caused by a single clonal group of strains, and revealed that the isolates of the outbreak were clustered into a large cluster with 3 Chinese strains and 1 Korean strain in the database, far away from the strains of other countries. Conclusion: The outbreak is caused by a single clone of Shigella sonnei, which are low virulence strains and have multiple drug resistance.

The development of artificial cervical disc replacement from the perspective of orthopedic bionic therapy / 中华外科杂志

The modern surgical treatment of cervical degenerative disc disease can be traced back to the advent of anterior cervical decompression and fusion.With the emergence of fusion-related complications,different scholars have promoted the gradual transformation of cervical degenerative disc diseases from "fusion fixation" to "non-fusion reconstruction" through in-depth fusion with materials science,engineering mechanics and other disciplines.The innovation of this treatment concept is consistent with the original intention of "structural remodeling,functional reconstruction,maximum repair and reconstruction of the morphology and function of skeletal muscle system" in orthopedic bionic treatment,which is essentially in line with the "bionic alternative therapy" in orthopedic bionic therapy.This paper focuses on the surgical treatment of cervical degenerative disc diseases,reviews the development history of artificial cervical disc replacement,analyzes the evolution from orthopedic biomimetic therapy,and explores a new direction for the design of artificial cervical disc prostheses and the treatment of cervical degenerative disc diseases in the future.

Effect of hypochloric acid on Escherichia coli biofilm and the clinical efficacy of hypochloric acid for wounds with Escherichia coli infection / 中华烧伤杂志

Objective: To investigate the effect of hypochloric acid on Escherichia coli biofilm and the clinical efficacy of hypochloric acid for wounds with Escherichia coli infection. Methods: One strain of Escherichia coli with the strongest bacterial biofilm forming ability among the strains isolated from specimens in 25 patients (16 males and 9 females, aged 32-67 years) from five clinical departments of the 940th Hospital of the Joint Logistic Support Force was collected for the experimental study from September to December 2019. The Escherichia coli was cultured with hypochloric acid at 162.96, 81.48, 40.74, 20.37, 10.18, 5.09, 2.55, 1.27, 0.64, and 0.32 μg/mL respectively to screen the minimum bactericidal concentration (MBC) of hypochloric acid. The Escherichia coli was cultured with hypochloric acid at the screened MBC for 2, 5, 10, 20, 30, and 60 min respectively to screen the shortest bactericidal time of hypochloric acid. The biofilm formation of Escherichia coli was observed by scanning electron microscopy at 6, 12, 24, 48, 72, and 96 h of incubation, respectively. After 72 h of culture, hypochloric acid at 1, 2, 4, 8, and 16 times of MBC was respectively added to Escherichia coli to screen the minimum biofilm eradicate concentration (MBEC) of hypochloric acid against Escherichia coli. After hypochloric acid at 1, 2, 4, and 8 times of MBEC and sterile saline were respectively added to Escherichia coli for 10 min, the live/dead bacterial staining kit was used to detect the number of live and dead cells, with the rate of dead bacteria calculated (the number of samples was 5). From January to December 2020, 41 patients with infectious wounds meeting the inclusion criteria and admitted to the Department of Burns and Plastic Surgery of the 940th Hospital of Joint Logistic Support Force of PLA were included into the prospective randomized controlled trial. The patients were divided into hypochloric acid group with 21 patients (13 males and 8 females, aged (46±14) years) and povidone iodine group with 20 patients (14 males and 6 females, aged (45±19) years) according to the random number table. Patients in the 2 groups were respectively dressed with sterile gauze soaked with hypochloric acid of 100 μg/mL and povidone iodine solution of 50 mg/mL with the dressings changed daily. Before the first dressing change and on the 10th day of dressing change, tissue was taken from the wound and margin of the wound for culturing bacteria by agar culture method and quantifying the number of bacteria. The amount of wound exudate and granulation tissue growth were observed visually and scored before the first dressing change and on the 3rd, 7th, and 10th days of dressing change. Data were statistically analyzed with one-way analysis of variance, Dunnett-t test, independent sample t test, Mann-Whitney U test, Wilcoxon signed-rank test, chi-square test, or Fisher's exact probability test. Results: The MBC of hypochloric acid against Escherichia coli was 10.18 μg/mL, and the shortest bactericidal time of hypochloric acid with MBC against Escherichia coli was 2 min. Escherichia coli was in a completely free state after 6 and 12 h of culture and gradually aggregated and adhered with the extension of culture time, forming a mature biofilm at 72 h of culture. The MBEC of hypochloric acid against Escherichia coli was 20.36 μg/mL. The Escherichia coli mortality rates after incubation with hypochloric acid at 1, 2, 4, and 8 times of MBEC for 10 min were significantly higher than that after incubation with sterile saline (with t values of 6.11, 25.04, 28.90, and 40.74, respectively, P<0.01). The amount of bacteria in the wound tissue of patients in hypochloric acid group on the 10th day of dressing change was 2.61 (2.20, 3.30)×104 colony forming unit (CFU)/g, significantly less than 4.77 (2.18, 12.48)×104 CFU/g in povidone iodine group (Z=2.06, P<0.05). The amounts of bacteria in the wound tissue of patients in hypochloric acid group and povidone iodine group on the 10th day of dressing change were significantly less than 2.97 (2.90, 3.04)×106 and 2.97 (1.90, 7.95)×106 CFU/g before the first dressing change (with Z values of 4.02 and 3.92, respectively, P<0.01). The score of wound exudate amount of patients in hypochloric acid group on the 10th day of dressing change was significantly lower than that in povidone iodine group (Z=2.07, P<0.05). Compared with those before the first dressing change, the scores of wound exudate amount of patients in hypochloric acid group on the 7th and 10th days of dressing change were significantly decreased (with Z values of -3.99 and -4.12, respectively, P<0.01), and the scores of wound exudate amount of patients in povidone iodine group on the 7th and 10th days of dressing change were significantly decreased (with Z values of -3.54 and -3.93, respectively, P<0.01). The score of wound granulation tissue growth of patients in hypochloric acid group on the 10th day of dressing change was significantly higher than that in povidone iodine group (Z=2.02, P<0.05). Compared with those before the first dressing change, the scores of wound granulation tissue growth of patients in hypochloric acid group on the 7th and 10th days of dressing change were significantly increased (with Z values of -3.13 and -3.67, respectively, P<0.01), and the scores of wound granulation tissue growth of patients in povidone iodine group on the 7th and 10th days of dressing change were significantly increased (with Z values of -3.12 and -3.50, respectively, P<0.01). Conclusions: Hypochloric acid can kill Escherichia coli both in free and biofilm status. Hypochloric acid at a low concentration shows a rapid bactericidal effect on mature Escherichia coli biofilm, and the higher the concentration of hypochloric acid, the better the bactericidal effect. The hypochloric acid of 100 μg/mL is effective in reducing the bacterial load on wounds with Escherichia coli infection in patients, as evidenced by a reduction in wound exudate and indirect promotion of granulation tissue growth, which is more effective than povidone iodine, the traditional topical antimicrobial agent.

Evaluation andreflection on the good donor practice / 中国输血杂志

Blood donors, as the core of blood collection and supply system, can greatly ensure blood safety and meet clinical demands with effective management. Good donor practice (GDP) is based on the cooperation of multiple departments by multiple methods. In accordance with the principles of science and ethnic, according to the number and frequency of blood donation and blood donation behavior, GDP classified blood donors accurately, and built up a procedure including potential blood donor identification, selection, recruitment, retention and caring to maintain an accurate management system for keeping regular blood donors. The evaluation indicators for the operation of GDP system were set to conduct real-time monitoring and evaluation, so as to achieve efficient and accurate management and ensure the long-term and stable supply of blood resources.

Predictive value of impedance of leadless pacemaker during implantation on trend changes of pacing threshold / 中华心血管病杂志

Objective: To explore the predictive value of the impedance measured during leadless pacemaker Micra implantation on the trend of changes of pacing threshold post implantation. Methods: This is a retrospective cross-sectional study. Patients who received implantation of leadless pacemaker Micra at the Second Xiangya Hospital of Central South University from December 2019 to August 2020 were enrolled. The clinical data and the intraoperative electrical parameters during leadless pacemaker implantation were collected. The impedance and pacing threshold data were analyzed at three time points: immediate release, 5-10 min after release, and after traction test. Receiver operating characteristic (ROC) curves and the area under the curve (AUC) were used to analyze the value of the impedance at immediate release on predicting the trend of changes of pacing threshold post implantation. Results: A total of 21 patients (mean age: (72.2±12.5) years, 12 males) were included. The impedance of 21 patients was (798.1±35.3) Ω immediately after implantation, (800.9±35.6) Ω after 5-10 minutes of release, and (883.6±31.7) Ω after traction test. Impedance was similar between the three time points (P>0.05). The threshold was (0.97±0.11) V/0.24 ms immediately after implantation, (0.95±0.12) V/0.24 ms at 5-10 min after the release, and (0.59±0.06) V/0.24 ms after the traction test. The threshold was significantly lower after the traction test than that immediately after release (P=0.003) and than that at 5-10 minutes after release (P=0.008), suggesting a decreased tendency of the threshold over time. According to the analysis of the ROC curve, the immediate impedance after the release ≥680 Ω could predict the ideal pacing threshold after the traction test (AUC=0.989, 95%CI 0.702-0.964, P<0.001), the prediction sensitivity was 87%, and the specificity was 100%. The pacing threshold would be not ideal with the immediate impedance ≤ 520 Ω (95%CI 0.893-1.000, P<0.001), the sensitivity was 100%, and the specificity was 80%. Conclusions: The impedance immediately after the release has predictive value for the changing trend of threshold post leadless pacemaker Micra implantation. Impedance ≥680 Ω immediately after release is often related with ideal pacing threshold after the traction test. In contrast, the impedance ≤ 520 Ω pacing is often related with unsatisfactory threshold after the traction test, therefore, it is recommended to find a new pacing site to achieve the impedance ≥680 Ω immediately after release during leadless pacemaker Micra implantation.

Primary cell culture and morphological observation of bulbar conjunctival fibroblasts in conjunctivochalasis / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To observe the growth status and morphological changes of primary cultured bulbar conjunctival fibroblasts in different stages of conjunctivochalasis(CCH), and to determine the best passage time, so as to obtain stable and consistent CCH bulbar conjunctival fibroblasts.METHODS: CCH primary bulbar conjunctival fibroblasts were obtained by tissue block adhesion method. The fibroblasts were purified by trypsin differential digestion method. The growth status and morphological changes of fibroblasts in different periods were observed and recorded under inverted microscope. The fibroblasts were identified by immunofluorescence cytochemical staining.RESULTS: After 24h of CCH conjunctival tissue adherent to the wall, a small number of cells would be seen crawling out around the tissue blocks. The logarithmic phase of cell growth was from the 2-7d. The cells grew fast, with vigorously proliferation, clear outline, uniform distribution, increas in numbers and clear nuclei. From the 9-15d, the cell growth entered the plateau stage, the tissue blocks gradually aged and lost activity. The cells grew slowly, arranged loosely, the volume became larger, the shape became flat, and a large number of granular substances and vesicles were produced in the cytoplasm. Some cells fell off from the bottom of the culture bottle, and large gaps appeared between the cells. After subculture and purification, the size and morphology of fibroblasts were basically the same. Through cell identification, fibroblasts were long spindle, flat star or multi-process spindle, wide in the middle, oval nucleus, relatively small at both ends, with 2-3 slender processes of different lengths extending outward.CONCLUSION: Primary CCH bulbar conjunctival fibroblasts can be successfully obtained by tissue block adhesion method. When the cells grow to the 8d, they can be digested and passaged to obtain stable and consistent CCH conjunctival fibroblasts.

Efficacy of percutaneous short segment fixation in the treatment of Magerl A3 thoracolumbar fractures with low bone mineral density:a retrospective study / 中国骨伤

OBJECTIVE@#To explore the clinical efficacy of percutaneous pedicle screw short segment internal fixation with or without the intermediate screw in the treatment of Magerl A3 thoracolumbar fractures with low bone mineral density.@*METHODS@#Patients with Magerl A3 thoracolumbar fracture underwent percutaneous pedicle screw short segment internal fixation from January 2017 to July 2020 were retrospectively analyzed, 93 cases met the diagnosis and inclusion criteria, 9 cases were excluded according to the exclusion criteria, and the remaining 84 cases obtained complete imaging follow-up data. There were 38 males and 46 females, the age ranged from 56 to 73 years old with an average of (64.78±7.12) years old, bone mineral density (BMD) ranged from 0.61 to 0.89 g/cm3 with an average of (0.73±0.14) g/cm3, the follow-up time was 11 to 25 months with an average of (17.58±6.12) months. There were 45 cases in group A with intermediate screw and 39 cases in group B without intermediate screw. The operation time and intraoperative blood loss were recorded, Oswestry Disability Index (ODI) and visual analogue scale (VAS) were used for clinical evaluation. The Cobb angle, vertebral wedge angle (VWA) and anterior vertebral body height (AVBH) were measured by X-ray after the operation. The corrected loss of the above parameters was calculated.@*RESULTS@#There were 5 cases of screw loosening in 84 patients (2 cases in group A and 3 cases in group B, P>0.05). There were significant differences in operation time and intraoperative blood loss between two groups(P<0.01). Clinical effects of two groups were good, postoperative VAS and ODI after operation obviously improved, there was no significant difference between two groups during all follow-up periods (3 days, 1 month after operation and the final follow-up) (P>0.05). Three days after the operation, the image evaluations (Cobb angle, VWA and AVBH) were significantly improved (P<0.05), but significant reduction loss was observed in both groups at 1 month after the operation and at the final follow-up (P<0.05). At the final follow-up, the loss of Cobb angle, VWA and AVBH in group A were (5.26±4.18) °, (4.63±3.80) ° and (9.54±8.71)%, respectively;group B was (6.01±4.34) °, (6.55±6.21) ° and (11.67± 9.95)%, respectively;however, there was no significant difference in reduction loss between the two groups(P>0.05).@*CONCLUSION@#Although the curative effect of the patients is satisfactory, the stability of the patients can not be improved by increasing the middle injured vertebra screw placement, the two groups of percutaneous short segment internal fixation can not resist the reduction loss of Magerl-A3 thoracolumbar fracture with low bone mineral density. Because the injured vertebra screw increases the operation time and intraoperative blood loss, it is not significant to use the intermediate screw for the elderly Magerl A3 thoracolumbar fractures with low bone mineral density.