Objective: To investigate the protective effects and mechanisms of acellular nerve allografts (ANA) on motor neurons in the spinal cord anterior horn of sciatic nerve injury ( SNI) rats . Methods: SPF grade male SD rats were randomly divided into normal , model , ANA-bridged (bridge group) , and autologous nerve transplantation groups (autograft group) , with 6 rats in each group . The SNI rat model was established using the right sciatic nerve clamp method for 10 mm . In the bridge group , the ANA was bridged to the two severed ends of the injured sciatic nerve , and in the autograft group , the autologous nerves were flipped head to tail and then bridged to the two se- vered ends . A spectrophotometer was applied to determine the DNA content in normal nerves and ANA . The foot- print test was used to determine the sciatic nerve function index (SFI) of the rats in each group , the wet weight ra- tio of the anterior tibialis muscle was calculated . The morphology and structure of the anterior horn motor neurons of the spinal cord of each group were observed by HE staining. The immunofluorescence and Western blot were used to detect Apaf-1 , Caspase-3 , Bcl-2 , Bax , and Cyt-C proteins expression in the L4-6 segment of the spinal cord . Results: The DNA content in the ANA prepared in this study was significantly lower than that in normal nerves (P < 0. 05) . Compared with the normal group , the SFI and wet weight ratio of the anterior tibialis muscle were re- duced in the model group (P < 0. 001) ; compared with the model group , both SFI and wet weight ratio of the ante- rior tibialis muscle significantly increased in the bridge group and the autografts group ( P < 0. 05 , P < 0. 001) , and the SFI and wet weight ratio of the anterior tibialis muscle in the autograft group were higher than those in the bridge group (P < 0. 001 , P < 0. 01) . The results of HE staining showed that the motor neurons in the anterior horn of the spinal cord of the normal group were structurally intact and had clear cytosolic boundaries; the neurons in the model group were lysed and necrotic , with blurred cytosolic boundaries; the neurons in the bridge group were less lysed and necrotic , but the nuclear translocation phenomenon could still be seen; the neurons in the autograft group were morphologically and structurally intact with clear cytosolic boundaries . Compared with the normal group , the expression of Apaf-1 , Caspase-3 , Bax and Cyt-C proteins significantly increased in the model group (P < 0. 001 , P < 0. 01 , P < 0. 01 , P < 0. 05) . Compared with the model group , the expression of Apaf-1 , Caspase- 3 , Bax , and Cyt-C proteins significantly decreased (P < 0. 001 , P < 0. 05 , P < 0. 05 , P < 0. 05) ; but the expres- sion of Bcl-2 protein significantly increased in the bridge group and the autograft group (P < 0. 05) . The expression of Apaf-1 , Caspase-3 , Bax and Cyt-C proteins in the autografts group was lower than that in the bridge group (P < 0. 001 , P < 0. 05 , P < 0. 05 , P < 0. 05) . Conclusion ANA can exert a protective effect on motor neurons in the anterior horn of the spinal cord of SNI rats by improving the morphology and structure of neurons , increasing the ex- pression of Bcl-2 protein , but decreasing the expression of Cyt-C , Bax , Caspase-3 , and Apaf-1 proteins in the spi- nal cord . The mechanism of ANA may be related to the Bcl-2/Cyt-C/Apaf-1-mediated mitochondrial apoptosis sig- naling pathway .

Objective:To explore the feasibility of applying BOPPPS (B-bridge in, O-objective, P-pre-assessment, P-participatory learning, P-post-assessment, S-summary) course design mode in the teaching of internal medicine practice for nursing undergraduates.Methods:A total of 73 nursing interns of Kunming Medical University were selected as subjects and divided into the experimental group ( n=30) and the control group ( n=43). The experimental group adopted the practice teaching method based on BOPPPS model, while the control group adopted the traditional teaching method. Students' evaluation was collected by questionnaire. The students' comprehensive reasoning ability, holistic nursing skills ability and clinical nursing evaluation ability were evaluated by taking out questions from the question bank. And the results of teachers' evaluation on the participation of case study and problem solving in the process of students' internship were collected. SPSS 20.0 was used for t-test. Results:The students' evaluation of the practice process in the experimental group (86.81±2.85) was significantly better than that in the control group (82.61±3.82) ( P<0.001). The experimental group was significantly better than the control group in comprehensive reasoning of clinical thinking and assessment of holistic nursing ability ( P <0.001). Teachers' evaluation in the experimental group was better than that in the control group ( P <0.05). The overall effect of the experimental group (20.60±1.73) was significantly better than that of the control group (17.84±1.70) ( P <0.001). Conclusion:BOPPPS mode is helpful for teachers to carry out and demonstrate holistic nursing teaching with symptoms as the core according to the overall teaching objectives of nursing internal medicine, optimize the time arrangement and knowledge structure, improve the practice efficiency, and promote the establishment of holistic nursing thinking mode of students.

Objective:To assess the effect of serum heat inactivation on the detection of 2019 novel coronavirus (2019-nCoV) specific IgM and IgG antibodies by colloidal gold method.Methods:The serum specimens were collected from a total of 106 Coronavirus Disease 2019 (COVID-19) patients and 52 control subjects. Both the fresh serum and the heat inactivated serum samples from the same patient were detected simultaneously with the 2019-nCoV IgM and IgG antibodies detection kit (colloidal gold method). According to the patient′s onset time, the positive rates of antibodies production profile were calculated. The influence of heat inactivation on the detection rates of antibodies at different stages of disease after onset was analyzed.Results:The test results of the specimens of the healthy control group before and after inactivation were all negative. For the 106 specimens of COVID-19 patients, the detection rates of 2019-nCoV specific IgM and IgG antibodies were reduced after heating at 56 ℃ for 30 min. The positive rates of IgM antibodies significantly decreased from 66.04% (70/106) to 43.40% (46/106) ( χ2=22.042, P=0.000), while the positive rates of IgG antibodies slightly decreased from 81.13% (86/106) to 76.42% (81/106) ( χ2=0.800, P=0.063). Further analysis revealed that there was a significant difference in the positive rates of IgM antibodies before and after heat inactivation in the 3rd, 5th and 6th week after onset. However, there was no statistically significant difference in the detection rates of IgG antibodies before and after serum heat inactivation in different periods of onset. Conclusions:Heat inactivation significantly decreased the detection rates of 2019-nCoV specific IgM antibodies, which may lead to serological false negative results.

Objective:To monitor and evaluate in vivo dose changes of intensity-modulated radiotherapy (IMRT) in patients with cervical cancer in a real-time manner. Methods:Twelve patients with cervical cancer admitted to our hospital were enrolled in this study. The in vivo doses were monitored by PerFRACTION?. Electronic portal imaging device (EPID) were collected in each treatment fraction for two-dimensional in vivo dose verification[γ index and dose difference (DD) index]. Log files were recorded for three-dimensional in vivo dose verification (γ index). The correlation between in vivo dose and treatment duration was analyzed by Pearson correlation analysis. Results:A total of 206 sets of EPID images and corresponding Log files were collected. The three-dimensional in vivo dose verification γ 1%/1mm of all patients was not correlated with treatment fraction ( P>0.05). Among them, the absolute difference of γ 1%/1mm of 94.66% fractions was< 1%. The mean DD 3% of two-dimensional in vivo dose verification of all patients was negatively correlated with treatment fraction ( P<0.05). Among which, the average γ 3%/3mm of 9 patients was>89% in the treatment fractions, and the average γ 3%/3mm of 98.57% fractions of these 9 patients was>93%. The other 3 patients had an average γ 3%/3mm ranged from 38% to 100%. CBCT images showed that the bladder volume of these 3 patients was significantly decreased with the relative changes by 82.08%, 84.41% and 73.59%, respectively, and the target area was retracted significantly with the relative changes by 38.12%, 59.79% and 24.46%, respectively. Conclusion:Combined with γ index and DD index, PerFRACTION? can monitor the mechanical stability of accelerator and MU delivery accuracy during treatment fractions, and monitor the changes of in vivo dose in patients with cervical cancer, which can improve the safety and quality assurance of IMRT for cervical cancer patients and provide guidance for patients with adaptive radiotherapy.

Objective: To analyze the concordance of KRAS, NRAS, BRAF and PIK3CA gene mutations detected in plasma and matched tumor tissues in colorectal cancer patients, in order to provide good evidences to support plasma could be a potential surrogate of tumor tissue for gene mutation test. Methods: One hundred and seventy-five cases of colorectal cancer were collected at the First Hospital of Jilin University, from October 2016 to October 2017.There were 101 males and 74 females, their ages ranged from 28 to 85 years,with median age of 59 years. The KRAS, NRAS, BRAF and PIK3CA gene mutations in the plasma and paired tumor specimens of all patients were detected by next generation sequencing. Results: The results of tissue samples test were gold standard. Comparison of the four genes showed that concordance rates between plasma and tissue samples were 81.1%(Kappa=0.543), 99.4%(Kappa=0.886), 99.4% (Kappa=0.886) and 97.7%(Kappa=0.714) respectively for KRAS, NRAS, BRAF and PIK3CA. The plasma detection rates of these genes were related to tumor stage(P=0.001), but not to gender(P=0.468) and age(P=1.000) of patients. Conclusions The study shows a high concordance of KRAS, NRAS, BRAF and PIK3CA gene mutations in plasma against mutation status in tumor tissue. In colorectal cancer, tumor tissue remains the best specimen for gene detection. However, patients from tumor tissue specimens cannot be obtained, especially those with advanced metastases, plasma can be used instead of tissue to detect the mutation status of KRAS, NRAS, BRAF and PIK3CA to guide targeted therapy.

Objective To analyze the concordance of KRAS, NRAS, BRAF and PIK3CA gene mutations detected in plasma and matched tumor tissues in colorectal cancer patients, in order to provide good evidences to support plasma could be a potential surrogate of tumor tissue for gene mutation test. Methods One hundred and seventy?five cases of colorectal cancer were collected at the First Hospital of Jilin University, from October 2016 to October 2017.There were 101 males and 74 females, their ages ranged from 28 to 85 years,with median age of 59 years. The KRAS, NRAS, BRAF and PIK3CA gene mutations in the plasma and paired tumor specimens of all patients were detected by next generation sequencing. Results The results of tissue samples test were gold standard. Comparison of the four genes showed that concordance rates between plasma and tissue samples were 81.1%(Kappa=0.543), 99.4%(Kappa=0.886), 99.4% (Kappa=0.886) and 97.7%(Kappa=0.714) respectively for KRAS, NRAS, BRAF and PIK3CA. The plasma detection rates of these genes were related to tumor stage(P=0.001), but not to gender(P=0.468) and age(P=1.000) of patients. Conclusions The study shows a high concordance of KRAS, NRAS, BRAF and PIK3CA gene mutations in plasma against mutation status in tumor tissue. In colorectal cancer, tumor tissue remains the best specimen for gene detection. However, patients from tumor tissue specimens cannot be obtained, especially those with advanced metastases, plasma can be used instead of tissue to detect the mutation status of KRAS, NRAS, BRAF and PIK3CA to guide targeted therapy.

Objective In clinical cerebral perfusion CT examination, repeated scanning the region of interest in the cine mode increases the radiation dose of the patients, while decreasing the radiation dose by lowering the scanning current results in poor image quality and affects the clinical diagnosis. We propose a penalized weighted least-square (PWLS) method for recovering the projection data to improve the quality of low-dose cerebral perfusion CT imaged. This method incorporates the statistical distribution characteristics of brain perfusion CT projection data and uses the statistical properties of the projection data for modeling. The PWLS method was used to recover the data, and the Gauss-Seidel (GS) method was employed for iterative solving. Adaptive weighting is introduced between the original projection data and the projection data after PWLS restoration. The experimental results on the clinical data demonstrated that the PWLS-based sinogram restoration method improved noise reduction and artifact suppression as compared with the conventional noise reduction methods, and better retained the edges and details to generate better cerebral perfusion maps.

Objective In clinical cerebral perfusion CT examination, repeated scanning the region of interest in the cine mode increases the radiation dose of the patients, while decreasing the radiation dose by lowering the scanning current results in poor image quality and affects the clinical diagnosis. We propose a penalized weighted least-square (PWLS) method for recovering the projection data to improve the quality of low-dose cerebral perfusion CT imaged. This method incorporates the statistical distribution characteristics of brain perfusion CT projection data and uses the statistical properties of the projection data for modeling. The PWLS method was used to recover the data, and the Gauss-Seidel (GS) method was employed for iterative solving. Adaptive weighting is introduced between the original projection data and the projection data after PWLS restoration. The experimental results on the clinical data demonstrated that the PWLS-based sinogram restoration method improved noise reduction and artifact suppression as compared with the conventional noise reduction methods, and better retained the edges and details to generate better cerebral perfusion maps.

Objective To study the expression level of PKM1 and PKM2 in colorectal cancer tissue and explore the relationship between colorectal cancer progression and their expression level.Methods The PKM1 and PKM2 protein expression levels in colorectal cancer tissues and adjacent tissues to carcinoma were determined by Western blot and Immunohistochemisty method, and the relationship with colorectal cancer were discussed. Results Western blot and Immunohistochemisty results all showed that, compared with adjacent noncancerous, the protein level of PKM1 decreases significantly in cancer tissues (P<0.05), while the protein level of PKM2 increases significantly in cancer tissues (P<0.05).The protein level of PKM1 is not relative with age,sex and stage of patients, but the protein level of PKM2 is relative with pTNM(P<0.05).Conclusion Colorectal cancer tissues with low level of PKM1 and high level of PKM2, and PKM2 was related with TNM of patients.