Clinical characteristics and prognosis of Omicron epidemic in Guang’an / 中国胸心血管外科临床杂志

@#Objective     To analyze the clinical characteristics of the Guang’an Omicron epidemic and summarize the management experiences and practices in pandemic prevention and control of major infectious diseases. Methods     Retrospective analysis was performed on patients infected with coronavirus disease (COVID-19), afterwards treated and observed in the isolation ward of Guang’an People’s Hospital and the shelter of Guang’an City from May 9 to June 26, 2022. The characteristics of patients at different age stages and the related factors affecting the severity, re-positive and negative conversion was analyzed. Results     Finally 1 278 patients were collected, including 508 males and 770 females, with an average age of 41.3±22.6 years. Among them, 1 054 patients were asymptomatic carriers. The overall severe rate was 0.86%, the severe rate of the high-risk group was 3.06%. The median negative conversion time was 10.0 days and re-positive rate was 7.36%. Patients aged>60 years were 2.589 times more likely to have a longer negative conversion time than those aged≤60 years (95%CI 1.921-3.489, P<0.001). Conclusion     The clinical characteristics of Guang’an COVID-19 epidemic are mainly that the elderly with high risk factors are more likely to develop severe cases, have longer clearance time, and re-positve is more likely to occur.

Analysis of the frontier and hotspot of screening technology for early lung cancer based on bibliometrics / 中国胸心血管外科临床杂志

@#Objective    To reveal and demonstrate the hotspots and further research directions in screening technology for early lung cancer, and provide references for the future studies. Methods    Researches related to lung cancer screening from 2011 to 2021 in the Web of Science database were included. Biblioshiny, a bibliometrics program based on R language, was used to perform content analysis and visualization of the included literature information. Results    Researches related to lung cancer screening were increasing year by year. Six major cooperation groups were formed between countries. The current research hotspots in the field of early lung cancer screening technology mainly focused on the multi-directional fusion of radiographic imaging, liquid biopsy and artificial intelligence. Conclusion    Low-dose spiral CT screening is still the most important and mainstream method for the screening of early lung cancer at present. The combination and integration of artificial intelligence with various screening methods and the innovation of novel testing and diagnostic equipment are the current research hotspots and the future research trend in this field.

Pyrroloquinoline quinone inhibited oxidative stress induced-apoptosis of Schwann cells via mitochondrial apoptotic signaling pathway in vitro / 中华整形外科杂志

Objective@#To investigate the mechanisms of Pyrroloquinoline quinone (PQQ) against oxidative stress induced apoptosis in Schwann cells (SCs).@*Methods@#SCs were cultured in vitro, identified by S-100 immunofluorence staining. SCs were divided into control group, H2O2 induced group, H2O2 + PQQ treated group. CCK-8 assay was used to detect cell proliferation. Apoptosis was detected by flow cytometry with Annecin V-FITC/PI staining, mitochondrial transmembrane potential was detected by flow cytometry with JC-1 labeled staining, cytochrome C (CytC), Bax and Caspase-9 protein levels was detected by Western blot analysis.@*Results@#In this study, the S-100 positive cells were more than 95%, cell proliferation was decreased in H2O2 induced SCs, apoptotic rate was increased, mitochondrial transmembrane potential was decreased, CytC, Bax and Caspase-9 protein levels were increased. After PQQ added, cell proliferation was increased, apoptotic rate decreased, mitochondrial transmembrane potential increased, CytC, Bax and Caspase-9 protein levels decreased.@*Conclusions@#PQQ protects SCs from oxidative induced apoptosis by inhibiting mitochondrial signaling pathway.

The roles of PI3K/Akt signal pathway in carboxymethylated chitosan protecting NO-induced chondrocytes apoptosis and the mechanisms / 中华风湿病学杂志

Objective To investigate the protective effects of carboxymethylated chitosan (CMCS) on nitric oxide (NO) induced apoptosis in rat chondrocytes, and the probable roles and mechanisms of PI3K/Akt signaling pathway in these process.Methods Rat knee articular cartilage was used as the source of chondrocytes, the cells were identified by immunohistochemical staining against collagen type Ⅱ, odium nitroprusside (SNP, 3 mmol/L) was used to establish the apoptotic models of chondrocytes.Cells were divided into four groups: the control group, the SNP-induced group, the SNP+CMCS treated group, the SNP+CMCS+PI3K inhibitor Wortmannin treated group.Cell proliferation were assessed by cell proliferation assay kit (CCK-8), the apoptotic rate of chondrocytes was determined by FCM with Annexin V-FITC/PI double staining, the expression levels of MMP-13 and TIMP-1 mRNA were detected by real-time polymerase chain reaction (PCR) analysis, the expression of Akt and p-Akt protein levels was detected by Western blotting analysis.One-way analysis of variance (ANOVA) statistical analysis was used to calculate the data.Results Three mmol/L SNP can inhibit proliferation (0.221±0.023), and the proliferation was reduced by 70％ compared with the control group (0.736±0.032, F=8.203, P=0.021);and the induced apoptosis in cultured chondrocytes could be observed.The apoptotic rate was (68.8±5.2)％.Increased MMP-3 and decreased TIMP-1 mRNA expression were observed in SNP-induced cells.After adding CMCS to SNP-induced chondrocytes, the proliferation was increased while apoptotic rate was decreased, the apoptotic rate decreased to (14.7±2.3)％.CMCS could promote the activation of p-Akt in SNP-induced chondrocytes and restore SNP-induced MMP-13 and TIMP-1 mRNA expression.Conclusion CMCS could protect apoptosis in SNP induced chon-drocvtes via activation of PI3K/Akt pathwav.

Carboxymethylated chitosan effect on cyclic adenosine monophosphate/protein kinase A signaling pathway in rat Schwann cells culturedin vitro / 中国组织工程研究

BACKGROUND:It has been confirmed that carboxymethylated chitosan has an promoting effect on Schwann cel proliferation and secretion, but its impact on the cyclic adenosine monophosphate-mediated protein kinase A signaling pathway in schwann cel stil needs further study. OBJECTIVE:To investigate the effect of carboxymethylated chitosan on cyclic adenosine monophosphate/ protein kinase A signaling pathway in rat schwann cels. METHODS:The Schwann cels of the second generation neonatal rats were obtained and seeded in 6-wel plate at a concentration of 1×109/L. These Schwann cels were cultured and divided into four groups. The Schwann cels in the control group were cultured by adding PBS. The Schwann cels in the experimental groups were cultured by adding 50, 100 and 200 mg/L of carboxymethyl chitosan solution, respectively. After 24 hours, the concentration of cyclic adenosine monophosphate, protein kinase A activity and cyclic adenosine monophosphate response element binding protein mRNA expression were detected. RESULTS AND CONCLUSION:Compared with the control group, carboxymethyl chitosan increased cyclic adenosine monophosphate concentrations, the activity of protein kinase A and cyclic adenosine monophosphate response element binding protein mRNA expression within the Schwann cels in a dose-dependent manner (P < 0.05). These results demonstrate that carboxymethyl chitosan can increase the concentration of cyclic adenosine monophosphate within the Schwann cels and promote protein kinase A activity, thereby activating cyclic adenosine monophosphate/protein kinase A signaling pathway.

Effects of pyrroloquinoline quinine on oxidative stress-induced apoptosis of Schwann cells and its mechanism / 中华整形外科杂志

<p><b>OBJECTIVE</b>To investigate the effects of Pyrroloquinoline quinine (PQQ) on hydrogen peroxide-induced apoptosis of Schwann cells (SCs) and its mechanism.</p><p><b>METHODS</b>SCs were isolated and cultured in vitro, and identified by S-100 immunofluorescence staining. The cultured SCs were divided into control group, hydrogen peroxide-treated group, hydrogen peroxide and PQQ treated groups. The intracellular superoxide dismutase (SOD) and malondialdehyde (MDA) content was detected; the apoptotic rate of SCs induced by hydrogen peroxide was determined by flow cytometry assay. The Hoechst33342 staining was used to detect the nuclear fragmentation and apoptotic nuclear condensation of SCs; the Rhodamine123 staining was used to detect the changes of mitochondrial membrane potential in SCs, the Western blot analysis was used to detect the expression of Bcl-2 in hydrogen peroxide induced SCs.</p><p><b>RESULTS</b>The SOD activity was significantly decreased and MDA level was increased in H2O2 induced SCs (P < 0.05), after addition of PQQ, the SOD content increased and MDA content decreased (P < 0.05). Flow cytometry results showed that the early apoptotic rate was 58.8% in H2O2 induced SCs, which has significant difference compared with the control group (P < 0.05), after addition of 10, 50, 100 nmol/L PQQ, the apoptotic rates were reduced to 33.7%, 18.7%, 3.9% respectively, showing significantly different with injured group (P < 0.05). Hoechst 33342 staining showed that H2O2 induced SCs had typical morphological characteristics, such as uptake of nuclear chromatin, nuclear shrinkage, nuclear fragmentation phenomenon. The proportion of apoptotic cells after PQQ treatment reduced. Rhodamine staining results showed that the H2O2 induced mitochondrial membrane potential reduction in SCs, which was reversed by addition of PQQ. Western blot analysis showed that the expression of Bcl-2 was decreased in H2O2 induced SCs, while it increased significantly after addition of PQQ (P < 0.05).</p><p><b>CONCLUSION</b>PQQ has a protective effect on oxidative stress-induced apoptosis of SCs.</p>

Carboxymethylated chitosan effects on proliferation of Schwann cells and expression of nuclear factor kappa B / 中国组织工程研究

BACKGROUND:Carboxymethylated chitosan is shown to promote some kinds of cells proliferation, but its effects on proliferation of Schwann cells need further studies. OBJECTIVE:To investigate the effects of carboxymethylated chitosan on proliferation of Schwann cells and expression of nuclear factor-κB in cultured Schwann cells. METHODS:Schwann cells from Sprague-Dawley rats at logarithmic growth phase were seeded in 96-wel plates, and cultured respectively with PBS, 0, 10, 50, 100, 200, 500, 1 000 mg/L carboxymethyl chitosan for 24 hours. cellproliferation was detected using the cellcounting kit-8 assay. After trypsin digestion, Schwann cells from Sprague-Dawley rats at logarithmic growth phase were used to prepare cellsuspensions, which were seeded in 6-wel cellculture plates and cultured respectively with 50, 100 and 200 mg/L carboxymethyl chitosan and PBS for 24 hours. Then, 5-bromo-2-deoxyuridine, real-time PCR and western blot assay were performed. RESULTS AND CONCLUSION:cellcounting kit-8 and 5-bromo-2-deoxyuridine detection results showed that carboxymethyl chitosan at 50-1000 mg/L, especial y at 200-500 mg/L, could promote Schwann cellproliferation. Real-time PCR and western blot results showed 50-200 mg/L carboxymethyl chitosan could promote nuclear factorκB mRNA and protein expression in Schwann cells in a dose-dependent manner, suggesting carboxymethyl chitosan can promote Schwann cellproliferation and expression of nuclear factor-κB in Schwann cells cultured in vitro.

Short-and medium-term efficacy of artificial cervical disc replacement versus fusion for cervical spondylosis / 中国组织工程研究

BACKGROUND:Recently, non-fusion technology representing as artificial cervical disc replacement continues to improve. On the basis of reconstruction of disc structure and function of involved segments, cervical spine structure of surgery area segment is significantly close to dynamic and static load stress distribution required by natural physiological systems. It effects are apparent in protecting intervertebral facet joints of degenerated segment and structure and function of the cervical spine of adjacent segments and in maintaining cervical dynamic stability, which presented obvious methodological strengths compared with segmental fusion technology. OBJECTIVE:To evaluate the clinical outcomes of anterior cervical discectomy and fusion and Bryan artificial cervical disc replacement in the treatment of single-level cervical spondylotic myelopathy or radiculopathy. METHODS:A total of 43 middle and old age patients with single-level cervical spondylotic myelopathy or radiculopathy, who were treated from March 2010 to March 2012, were enrol ed in this study. They were randomly assigned to anterior cervical discectomy and fusion group (fusion group) and Bryan artificial cervical disc replacement group. Range-of-motion of cervical overal and adjacent intervertebral area near the intervertebral space was observed with radiography. During fol ow-up, postoperative recovery of neurological function was evaluated using Japanese Orthopaedic Association scale, visual analog scale and neck disability index. RESULTS AND CONCLUSION:None patients experienced complications of neurovascular injury during and after the surgery. Range-of-motion of postoperative overal cervical vertebra and adjacent joint was improved in the Bryan artificial cervical disc replacement group compared with the fusion group. Neurological function was apparently improved after surgery in each group. At 3 months after surgery, scores of Japanese Orthopaedic Association, visual analog scale and neck disability index were significantly improved in the Bryan artificial cervical disc replacement group compared with the fusion group (P<0.05). During final fol ow-up, there were significant differences in visual analog scale scores between the two groups. Japanese Orthopaedic Association scale score and neck disability index score were similar between the two groups. During fol ow-up, no prosthesis sinking, displacement or heterotopic ossification were detected. These data indicated that artificial cervical disc replacement could effectively keep the range of motion of cervical segments and protect disc degeneration of adjacent segment. Mid-term fol ow up obtained similar improvement of neurological function of fusion surgery. The moderate-term and short-term efficacies of non-fusion technology were better than fusion technology in the treatment of single-level cervical spondylopathy.

The role of p38 MAPK signal pathway in carboxymethylated chitosan protecting NO-induced chondrocytes apoptosis and the mechanisms / 中华风湿病学杂志

Objective To study the effects of carboxymethylated chitosan (CMCS) to nitric oxide (NO)-induced apoptosis on rat chondrocytes,and explore p38MAPK signal transduction pathway in the process and its mechanism.Methods The rat articular cartilage cells were cultured in vitro,collagen type-2 (collagen-2) immunohistochemical staining was used to identify the cartilage cells.The model of chondrocyte apoptosis was built by different concentrations of sodium nitroprusside (SNP) induction.The cells were divided into the control group,the SNP treated group SNP+CMCS treated group,and the SNP+p38 MAPK inhibitor SB203580 treated group.The apoptotic rate of chondrocytes was calculated by FCM,apoptotic nuclei was identified by Hoechst33342 stain,the mitochondrial membrane potential changes was detected by Rhodamine123 (Rho123) stain,the expression of p38 and p-p38 were detected by Western blotting analysis.Results 1-3 mmol/L SNP could induce chondrocyte apoptosis,the apoptotic rate was increased with the SNP increasing,the most obvious apoptosis was occurred in 3 mmol/L SNP treated chondrocytes,which was 69.8％ (P＜0.05).SNP could increase the nuclear fragmentation of chondrocytes,the cells with nuclear fragmentation was significantly higher than that in the control group.SNP could reduce mitochondrial membrane potential in chondrocytes,which decreased significantly compared with the control group.SNP could increase the p-p38 expression in chondrocytes,which was 4.3 times compared to the control group.CMCS of different concentrations could reduce the apoptotic rate of SNP-induced chondrocytes,which was 51.0％,29.9％ and 15.2％,which was decreased significantly (P＜0.05) when compared with 3 mmol/L SNP induced group,CMCS decreased the cells number of SNP-induced nuclear fragmentation.CMCS increased the mitochondrial membrane potential in SNP-induced chondrocytes.CMCS reduced the expression levels of p-p38 in SNP-induced chondrocytes.Conclusion CMCS has protective effect on SNP-induced apoptosis of chondrocytes.This process is completed by inhibiting the activity of p38 MAPK signal pathway.

A study of Escherichia coli phylogenetic groups and antimicrobial resistance in elderly urinary tract infections / 中华老年医学杂志

Objective To study the relationship between Escherichia coli (E.coli.) phylogenetic groups and the antimicrobial resistance in elderly patients with urinary tract infections.Methods 133 Escherichia coli were collected from elderly patients with urinary tract infections in 3 general hospitals in Tianjin.Kirby Bauer method was used to test susceptibility of E.coli.to four antibiotics.Escherichia coli DNA was extracted by boiling method.Phylogenetic groups (A,B1,B2 and D) of the E.coli was isolated by the two-step triplex-PCR.Results In all the strains,levofloxacin resistance rate was the highest (54.1％,72 strains),piperacillin/tazobactam resistance rate was the lowest (15.0％,20 strains) (Z=51.57,P＜0.01).The detection rates of Escherichia coli phylogenetic group A,B1,B2 and D were 24.8％ (33 strains),15.0％ (20 strains),18.0％ (24 strains),42.1％(56 strains) (Z=31.2,P＜0.01).Levofloxacin-sensitive strains were more common in Escherichia coli phylogenetic group B2 strains,and there was a significant difference in the strain number between the resistant and sensitive strains [29.5％ (18/61) vs.8.3％ (6/72),x2 =10.01,P＜0.01].Levofloxacin-resistant strains were more common in Escherichia coli phylogenetic group D strains,and there was a significant difference in the strain number between the resistant and sensitive strains [31.1％ (19/61) and 51.4 ％ (37/72),x2 =5.55,P＜0.05].There was no significant relationship between the Escherichia coli phylogenetic groups and the other three antibiotic resistance (all P＞0.05).Conclusions The detection rates of group D are the highest in the Escherichia coli phylogenetic groups,and it has a relationship with levofloxacin resistant.The antimicrobial resistance can be estimated by phylogenetic analysis in elderly patients with E.coli urinary tract infections.

A comparative study on repairing bone defect with autograft and the composite of beta-tricalcium phosphate-hyaluronic acid-type Ⅰ collagen-bone marrow stromal cells / 中国组织工程研究

BACKGROUND:Compared with traditional autogenous bone graft, composite, as the carrier of seed cells, possesses advantages of fewer traumas and no limitation of donor site in repairing bone defect.OBJECTIVE: To observe the ability of the composite of β-tricalcium phosphate artificial bone-hyaluronic acid-type I collagen (β-TCP/HA/COL-I), as induced bone marrow stromal cell (MSC) carrier, to repair rabbit radial defect, and the feasibility with the composite as bone substitute material.DESIGN: A randomized and controlled trial.SETTING: Department of Orthopaedics, Renmin HospitaL, Wuhan University.MATERIALS; The study was conducted in the Department of Orthopaedics Renmin Hospital, Wuhan University between September 2003 and July 2004. Thirty-one New Zealand big white rabbits, aged 6 months, with body mass of 1.5 to 2.0 kg were enrolled in this study. The rabbits were randomized into control group (n =4) and experimental group (n =27).METHODS : ①In vitro induction and culture of MSCs was performed on 31 white rabbits, and the alkaline phosphatase (ALP) positive ratio of induced MSCs was observed. The structure of β-TCP/HA/COL-I was observed under scanning electron microscope. ② A 2 cm radial defect was created through operation. Eight weeks later, composites of β-TCP/HA/COL-I/MSCs were implanted into one side of rabbits in the experimental group, and autogenous bone was implanted into the other side. Rabbits in the control group were untouched. ③All the animals in the experimental group were randomly sacrificed at postoperative 4,8 and 12 weeks, 6 rabbits at 4 and 8 weeks, 15 at 12 weeks; Animals in the control group were sacrificed at 12 weeks. Gross observation, X-ray photographing, haematoxylin-eosin (HE) dyeing, and assessment of inorganic ingredient were performed. Osteogenic area and biomechanical tests were performed at 12weeks. Repairing effects on bone defect in each group were compared.MAIN OUTCOME MEASURES: The ALP positive ratio of induced MSCs; The structure of composite ofβ-TCP/HA/COL-I;Gross observation; X-ray photographing; HE dyeing and assessment of inorganic ingredient; Osteogenic area and biomechanical tests.RESULTS: All the 31 rabbits entered the stage of result analysis. ① The ALP positive ratio of cells reached 75% after induction and culture. ② Scanning electron microscope observation showed that 3 kinds of materials with abundant cellular structure distributed evenly. ③ The osteogenic area at 12 weeks was (72.5±3.6)% and (76.7±6.2)% in the experimental group and autogenous group, respectively (P ＞ 0.05). ④The maximum bending moment was (521.0±61.1) and (554.3±53.3)N·mm in the experimental group and control group, respectively; The maximum displacement at point of application of force was (0.816±0.071)and (0.870±0.103)respectively, without significant difference (P ＞ 0.05). ⑤Inorganic ingredient in the composite was 75%, 57% and 42% at 4,8 and 12 weeks respectively, suggesting that the inorganic component in the material was gradually decomposed with the elongation of time. ⑥Results of gross observation,X-ray photographing, histopathological examination, biomechanical test showed that with the elongation of time, composite of β-TCP/HA/COL-I/MSCs could repair bone defect in the experimental group, while bone defect in the control group had not been repaired.CONCLUSTON: Composite of β-TCP/HA/COL-I /MSCs possesses the same effect on repairing bone defect as autogenous bone, so it may be used as autogenous bone graft substitute.