Objective To study the effect of Exendin-4 on oxidative stress and neural apoptosis following spinal cord injury (SCI). Methods Adult male SD rats, with weight between 200-250 g, were randomly divided into three groups (12 in each group):Sham group, SCI group and Exendin-4 group (Ex-4 group). Rats in Sham group achieved spinal cord exposure. SCI group and Ex-4 group were induced according to Allen′s test (using a weight-drop device). Rats in Ex-4 group were ad?ministrated with Exendin-4 (10 μg/rat) through intraperitoneal injection immediately after establishment of SCI models. Rats in Sham group and SCI group were given the same volume of normal saline solution instead. Level of malondialdehyde (MDA) and the activity of catalase (CAT) were assessed in spinal cord tissues 24 hour after drug administrations. Neural apoptosis was detected by TUNEL staining and the expression levels of caspase-9 and AIF were determined using Western blot. Results Compared with Sham group, the levels of MDA, caspase-9 and AIF as well as neuronal apoptosis rate in?creased obviously, while activity of CAT decreased markedly in SCI group(P<0.01). Compared with SCI group, the levels of MDA, caspase-9 and AIF as well as the neuronal apoptosis rate decreased obviously, while activity of CAT increased re?markably in Exendin-4 group(P < 0.01). Conclusion Exendin-4 restrain neural apoptosis following spinal cord injury through relieving oxidative damage.

Objective To investigate the effects of hydrogen sulfide on autophagy and the apoptosis after acute spinal cord injury in rats. Methods Thirty-six adult male SD rats (250-300 g) were randomly divided into three groups (n=12 for each group):sham operation group (Sham group), spinal cord injury group (Model group) and hydrogen sulfide pre-treatment group (H2S group). Allen’s method was used to establish the rat model of spinal cord injury. Rats of sham operation group re?ceived only laminectomy. Rats of H2S group received sodium hydrosulphide injection intraperitoneally (50μmol/kg) 1h after spinal cord injury, and Model group was given the same amount of saline solution. Rats in the three groups were sacrificed 24 h after spinal cord injury, then the spinal cord was removed. The expressions of LC3, p70S6K and Cleaved caspase-3 were detected by Western blot assay. The expression of LC3 was also detected by immunofluorescence. The cell apoptosis was as?sessed by TUNEL stain. Results Compared with Sham group, the expression levels of LC3Ⅱ/LC3Ⅰand Cleaved caspase-3 were increased in Model group, but the expression of p70S6K decreased and cell apoptosis increased in Model group (P<0.01). Compared with Model group, the expression levels of LC3Ⅱ/LC3Ⅰand Cleaved caspase-3 were decreased significant?ly, while the expression of p70S6K increased and cell apoptosis decreased significantly in H2S group (P < 0.01). Conclu?sion Hydrogen sulfide can inhibit autophagy and reduce cell apoptosis after acute spinal cord injury in rats.

Objective To investigate the effects of edaravone (EDA) on cell apoptosis induced by endoplasmic reticu?lum stress (ESR) after spinal cord injury (SCI) in rats. Methods Thirty-six healthy adult SD rats were randomly divided in?to three groups (12 rats for each group):Sham group, SCI group and EDA group. The rat model of SCI was made by Allen’s method and the sham group was only received laminectomy and kept the spinal cord intact. Rats in sham group and SCI group accepted the same volume and frequency of saline injection as EDA group. The EDA group was given 10 mg/kg EDA once every 12 h intraperitoneally. Three days after injuring, the spinal cords were harvested, and the protein levels of C/EBP homologous protein (CHOP), Cleaved caspase-12 and Cleaved caspase-3 were detected by Western blot assay. Immunofluo?rescence staining was used to analyze the positive ratio of caspase-12 and CHOP in spinal cord of three groups. Meanwhile, TUNEL staining was used to identify cell apoptosis of spinal cord. Results Compared with sham group, the protein levels of CHOP, Cleaved caspase-12 and Cleaved caspase-3 were obviously higher in SCI group (P<0.01);the proportion of Cas?pase-12 and CHOP positive cells was significantly increased (P<0.01), and the apoptotic rates were also significantly in?creased in spinal cord (P<0.01). However, compared with SCI group, the protein levels of CHOP , Cleaved caspase-12 and Cleaved caspase-3 were significantly decreased in EDA group (P<0.01);the proportion of Caspase-12 and CHOP positive cells was significantly reduced (P<0.01), and the apoptotic rates were also significantly decreased in spinal cord (P<0.01). Conclusion EDA has neuroprotective potential to spinal cord injury. The mechanism of its neuroprotective effect may asso?ciate with its inhibitory effect to the cell apoptosis induced by endoplasmic reticulum stress after SCI.

Objective To evaluate the accuracy and feasibility of S2 alar-iliac screwing assisted by an individualized navigation template in clinic.Methods Five patients underwent S2 alar-iliac screwing from March 2015 to July 2017.They were 2 men and 3 women,aged from 41 to 61 years (average,54.8 years).After their preoperative CT scan data of the pelvis were used for 3D reconstruction,their individualized navigation templates were designed,3D printed and used to assist the implantation of S2 alar-iliac screws.After operation,their postoperative CT data were reviewed and reconstructed using software Mimics.The caudal angulation on the sagittal plane (sagittal angle,SA),lateral angulation on the transverse plane (transverse angle,TA),horizontal distance to the median sacral crest (horizontal distance,HD),and vertical distance to the first posterior sacral foramen's inferior margin (vertical distance,VD) of the screws were measured and compared with the corresponding values in the preoperative design.Results In the 5 patients,altogether 10 S2 alar-iliac screws were implanted through the sacroiliac joint without piercing the iliac bone cortex.There were no significant differences between the preoperative design and postoperative measurements in terms of SA (32.22°±5.57° versus 31.95°±5.78°),TA (42.59°±4.55° versus 42.21°± 5.29°),HD (5.04 ± 0.40 mm versus 5.00 ± 0.41 mm) orVD (19.58 ± 1.49 mm versus 19.54±1.12 mm) (P ＞ 0.05).Conclusion In the adult pelvic fixation,the S2 alar-iliac screwing can be assisted by an individualized navigation template to achieve high accuracy in implantation.

Objective To compare the accuracy of the lung ultrasound and pulse indicator continuous cardiac output (PiCCO) in predicting volume responsiveness in septic shock patients with myocardial suppression.Methods Fifty patients of both sexes with septic shock complicated with myocardial depression,aged ≥ 18 yr,were enrolled in the study.The method for fluid replacement test was as follows:0.9％ sodium chloride injection or lactated Ringer's solution 500 ml was rapidly infused intravenously.PiCCO was used to monitor cardiac output,stroke volume,extravascular lung water index (EVLWI),pulmonary vascular penetration index (PVPI),intra-thoracic blood volume index and global end-diastolic volume index.The chest wall was scanned by ultrasound and the lung ultrasound score (LUS) was assessed.Positive fluid responsiveness was defined as an increase in PiCCO-monitored cardiac output＞ 10％ after fluid replacement.Patients were divided into positive fluid responsiveness group and negative fluid responsiveness group according to the results of fluid resuscitation test.The receiver operating characteristic (ROC) curve was drawn to evaluate the accuracy of each index in predicting fluid responsiveness.Results Compared with negative fluid responsiveness group,EVLWI,PVPI and LUS were significantly decreased,the number of patients in whom the bilateral anterior chest wall presented as B-line was increased in positive fluid responsiveness group (P＜0.01).The area under the ROC curve and 95％ confidence interval of LUS in predicting volume responsiveness was 0.836 (0.720-0.952),the cutoff value was 14.5 points,sensitivity 88％,and specificity 72％.The area under the ROC curve and 95％ confidence interval of EVLWI in predicting volume responsiveness was 0.818 (0.701-0.936),the cutoff value was 9.6 ml/kg,sensitivity 84％,and specificity 72％.The area under the ROC curve and 95％ confidence interval of PVPI in predicting volume responsiveness was 0.720 (0.575-0.865),the cutoff value was 1.55,sensitivity 92％,and specificity 52％.Conclusion The lung ultrasound and PiCCO produce higher accuracy in predicting volume responsiveness in septic shock patients with myocardial suppression;LUS has more advantages due to non-invasive examination.

Objective To compare the accuracy of inferior vena cava (IVC) ultrasound,central venous pressure (CVP) and pulse indicator continuous cardiac output (PiCCO) in predicting fluid responsiveness in septic shock patients with myocardial depression.Methods Fifty patients with septic shock complicated with myocardial depression,aged ＞ 18 yr,were enrolled in the study.The method for fluid replacement test was as follows:0.9％ sodium chloride injectionor lactated Ringer's solution 500 ml was intravenously infused over 20 min,and positive fluid responsiveness was defined as an increase in PiCCO-monitored CO＞ 10％ after fluid replacement.Patients were divided into positive fluid responsiveness group and negative fluid responsiveness group according to the fluid replacement test.PiCCO was used to monitor stroke volume (SV),stroke volume variation (SVV) and pulse pressure variability (PPV) before fluid replacement,CVP was measured,and the diameter of IVC (d-IVC) and variability of IVC (v-IVC) were measured by bedside ultrasound.The receiver operating characteristic curve was drawn to evaluate the accuracy of each index in predicting fluid responsiveness.Results Compared with negative fluid responsiveness group,d-IVC was significantly decreased and v-IVC,SVV and PPV were increased before fluid replacement in positive fluid responsiveness group (P＜0.01).Three point five mmHg,14.5 mm,16.5％,17.0％ and 11.5％ were selected as the cutoff value for CVP,d-IVC,v-IVC,SVV and PPV,respectively.The sensitivity of CVP,d-IVC,v-IVC,SVV and PPV in predicting fluid responsiveness was 100％,92％,80％,44％ and 68％,respectively,and the specificity was 28％,80％,72％,100％ and 72％,respectively,and the area under the receiver operating characteristic curve (95％ confidence interval) was 0.609 (0.450-0.768),0.862 (0.750-0.974),0.777 (0.642-0.911),0.734 (0.596-0.873) and 0.733 (0.594-0.872),respectively.Conclusion PiCCO and IVC ultrasound provide higher accuracy in predicting fluid responsiveness in septic shock patients with myocardial depression,and IVC ultrasound is more superior because of non-invasive examination.

Objective:To analyze the factors influencing the difference in location of cricothyroid membrane between traditional surface palpation and ultrasonic biplane.Methods:One hundred and seven subjects of both sexes, aged 18 yr, underwent neck ultrasound examination in our hospital from August 2021 to December 2021, were selected.The structure of cervical airway was observed by ultrasound.The subjects in whom the structure of cricothyroid membrane was clearly shown were selected.The middle point of cricothyroid membrane was located by otorhinolaryngologist using surface palpation method and by ultrasonic doctor using ultrasonic biplane method.The distance between two positioning points was measured by a ruler.The subjects were divided into accurate group (distance between two points≤3 mm) and difference group (distance between two points>3 mm). The distance between cricoid cartilage and thyroid cartilage (spacing of cricoid cartilage and thyroid cartilage) and distance between the midpoint of cricothyroid membrane and skin (spacing of cricothyroid membrane and skin) were measured by ultrasound.The neck length and the maximum submaxillary distance in head up were measured by a ruler.The factors influencing the difference in location between the two methods were analyzed by multivariate logistic regression.Results:One hundred and four subjects with clear cricoid cartilage and cricothyroid membrane under ultrasound were selected.There were significant differences in the ratio of gender, body mass index (BMI), cricothyroid membrane-skin distance, neck length, and maximum submandibular distance between the two groups ( P<0.05). Multivariate logistic analysis showed that female ( OR=9.091, P<0.001), BMI ( OR=11.214, P=0.001) and increased cricothyroid membrane-skin distance ( OR=5.649, P=0.015) were the factors influencing the difference in location between the two cricothyroid membrane localization methods. Conclusions:Female, obesity (BMI>28.0 kg/m 2) and increased distance between cricothyroid membrane and skin are the factors affecting the difference in location of cricothyroid membrane between ultrasonic biplane method and surface palpation method, and bedside ultrasound is recommended for location in those with the factors mentioned above.

OBJECTIVE: To explore the genetic basis for a patient with Alport syndrome (AS) and confirm the existence of a splicing variant. METHODS: An AS patient diagnosed at the Affiliated Hospital of Inner Mongolia Medical University on January 8, 2021 for significant proteinuria and occult hematuria was selected as the study subject. Clinical data was collected. Peripheral blood samples were collected for the extraction of genomic DNA. Whole exome sequencing and Sanger sequencing were carried out to identify potential genetic variants. An in vitro experiment was also conducted to verify the abnormal mRNA splicing. Bioinformatic software was used to analyze the conservation of amino acids of the variant sites and simulate the 3D structure of the variant collagen IV protein. Immunofluorescence and immunohistochemistry were carried out on renal tissues from the patient to confirm the presence of AS kidney injury. RESULTS: The patient, a 21-year-old male, had a 24-hour urine protein of 3.53 g/24 h, which fulfilled the diagnostic criteria for proteinuria. His blood uric acid has also increased to 491 μmol/L. DNA sequencing revealed that he has harbored a c.835-9T>A splice variant of the COL4A5 gene, which was not found in either of his parents. In vitro experiment confirmed that the variant has removed 57 bp from the exon 15 of the mRNA of the COL4A5 gene. The deletion may cause loss of amino acid residues from positions 279 to 297, which in turn may affect the stability of the secondary structure of the α5 chain encoded by the COL4A5 gene. The amino acids are conserved across various species. The result of homology modeling indicated that the trimerization of Col-IV with the mutated α5 chain could be achieved, however, the 3D structure was severely distorted. The AS kidney damage was confirmed through immunofluorescence assays. Based on the guidelines from the American College of Medical Genetics and Genomics, the c.835-9T>A variant was classified as likely pathogenic (PVS1_Moderate+PS3_Moderate+PM2_Supporting+PS2+PP3+PP4). CONCLUSION The c.835-9T>A variant of the COL4A5 gene probably underlay the AS in this patient. In vitro experiment has confirmed the abnormal splicing caused by the variant. Histopathological examination of the kidney tissue has provided in vivo evidence for its pathogenicity. Above finding has expanded the mutational spectrum of the COL4A5 gene.
Humans ; Male ; Young Adult ; Amino Acids ; China ; Collagen Type IV/genetics* ; Exons ; Nephritis, Hereditary/genetics* ; RNA Splicing

Objective:To analyze the cardio-pulmonary ultrasound features of cardiogenic pulmonary edema (CPE) and pneumonia in adults with acute dyspnea, and to construct a differential diagnosis model.Methods:Seven hundred and forty-three patients with sudden acute dyspnea admitted to Hebei General Hospital from November 2018 to May 2022 were retropectively included. Ultrasonographer A performed lung ultrasound with 12 zone method, and interpreted and recorded the ultrasonic signs (including A-lines area, B-lines area, consolidation area and pleural effusion area) together with ultrasonographer B. According to the ultrasonic characteristics of the whole lung, it was divided into A-profile and B-profile. According to the continuity and symmetry of the distribution of B-lines in bilateral lung fields, it could be divided into bilateral lung continuous and discontinuous B-profile, bilateral lung symmetric and asymmetric B-profile. Left ventricular ejection fraction (LVEF), left ventricular filling pressure (E/e′), right ventricular dilatation, tricuspid annular systolic displacement (TAPSE) and inferior vena cava diameter (IVCD) were evaluated by echocardiography, and all the indexes were transformed into binary variables. According to the final clinical diagnosis and treatment results, the disease was divided into CPE group and pneumonia group. Binary Logistic regression model was used to screen independent influencing factors, and partial regression coefficient β value was used as a weight to assign a score, and a differential diagnosis model was established based on the total score. The predictive value of the model was evaluated by the receiver operating characteristic curve (ROC) and area under curve (AUC). After the model was built, 30 patients with CPE or pneumonia were independently collected by ultrasonographer C as external validation data, which were included in the model to draw ROC curve and evaluate the differential diagnosis efficiency of the model. The consistencies between ultrasonographer A and B, A and C in observing lung ultrasound were explored.Results:A total of 743 patients from 43 clinical departments were included, including 246 cases in CPE group and 497 cases in pneumonia group. Multivariate logistic regression analysis showed that bilateral lung continuous B-profile, bilateral lung symmetric B-profile, ≥1 pleural effusion area, LVEF<50%, E/e′>14 were the risk factors for CPE (all OR>1, P<0.05), and ≥1 consolidation area and ≥1 pleural sliding disappearance area were the protective factors for CPE (all OR>1, P<0.05). The sensitivity, specificity and AUC of combined cardio-pulmonary ultrasound index β value weight score in the differential diagnosis of CPE and pneumonia were 0.939, 0.956 and 0.986, respectively. The AUC of external validation data was 0.904. Ultrasonographer A and B, A and C had good consistency in the interpretation of lung ultrasound signs ( P<0.05). Conclusions:The differential diagnosis model based on combined cardio-pulmonary ultrasound indexes has high differential diagnosis efficiency for CPE and pneumonia, and can be used in bedside cardio-pulmonary ultrasound practice.

BACKGROUND:Intervertebral disc degeneration is clinically considered to be the main cause of low back pain,but due to the unclear pathogenesis of intervertebral disc degeneration,there is still a lack of effective means to delay the progression of the disease.Single-cell RNA sequencing technology can amplify and sequence mRNA at the single-cell level,reveal the gene expression intensity of a single cell,discover different cell subsets in tissues according to the heterogeneity of cells,study the pathogenesis of intervertebral disc degeneration at the molecular level,and provide a new theoretical basis for its early diagnosis and treatment. OBJECTIVE:To introduce the basic principles of single-cell RNA sequencing technology and review the research progress of single-cell RNA sequencing technology in intervertebral disc degeneration in recent years. METHODS:A computer was used to search PubMed,Web of Science,CNKI and WanFang databases for the literature published from 2012 to 2022.Key words were"single-cell RNA sequencing,intervertebral disc degeneration,sequencing Technology"in Chinese and English.Duplicate,poor-quality and irrelevant articles were excluded;a total of 70 articles were eventually included. RESULTS AND CONCLUSION:(1)We identified new cell subsets such as homeostatic chondrocytes,hypertrophy chondrocyte-like nucleus pulposus cells and fibrous nucleus pulposus cells,identified the marker genes and transcription factors of these cell subsets,and described the functions,differentiation paths and cell fate of these cell subsets during the development and progression of intervertebral disc degeneration,and proposed the concept of progenitor nucleus pulposus cells.A cell subpopulation with progenitor nucleus pulposus cells properties was identified and its effectiveness in treating intervertebral disc degeneration was verified in mice.(2)Fibro chondrocyte-like annulus fibrosus cells and annulus fibrosus stem cells with both cartilage and fiber properties were identified,and a new type of composite hydrogel was prepared by combining fibrous cartilage inducers silk fibroin and hyaluronic acid in vitro.Experiments in mice demonstrated that this hydrogel could repair both annulus fibrosus tissue and cartilage matrix,and was remarkably effective in the treatment of intervertebral disc degeneration.(3)Regulatory chondrocytes were found in endplate cartilage.Two distinct fates in the progression of intervertebral disc degeneration were analyzed and the differential genes in the two fates were identified.Intercellular communication analysis indicated that regulatory chondrocytes interact with endothelial cells to promote angiogenesis.(4)Immune cells such as macrophages,T cells,myeloid progenitor cells and neutrophils were identified in the degenerated intervertebral disc tissues,demonstrating the existence of immune response during intervertebral disc degeneration.It was found that apolipoprotein induced the polarization of macrophages M1 and M2 subtypes,and this polarization process affected the activity of progenitor nucleus pulposus cells by amplifying the inflammatory response through the MIF signaling pathway.