Objective To observe the value of deep learning image reconstruction(DLIR)algorithm in brain CT perfusion(CTP)using a protocol of 70 kVp and 40 ml contrast agent dose.Methods Totally 105 patients with suspected acute ischemic stroke(AIS)were prospectively enrolled and randomly divided into 3 groups,who underwent standard dose CTP scanning with 80 kVp and 150 mA combined with reconstruction as adaptive statistic iterative reconstruction V(ASIR-V)at 50％level(CN group,n=35),low dose(LD)scanning with 70 kVp and 100 mA combined with DLIR reconstruction at the highest level(DLIR-H)(LD group,n=35),or ultra-low dose(ULD)scanning with 70 kVp and 70 mA combined with DLIR-H reconstruction(ULD group,n=35).Radiation doses were compared among 3 groups.CT values and standard deviations(SDCT)of ROI of gray matter and white matter in the frontal,parietal and temporal lobes were measured.Signal-to-noise ratio(SNR)and contrast-to-noise ratio(CNR)between gray and white matter were calculated and compared among groups.Then pseudo-color images of cerebral blood volume(CBV),cerebral blood flow(CBF),mean transit time(MTT)and time to maximum of the tissue residual function(Tmax)were generated.The imaging quality of CTP pseudo-color images was evaluated,and the compatibility of the subjective scores within every kind of CTP pseudo-color images were assessed using Kappa test.Quantitative perfusion parameters were measured and compared among groups.Results Compared with CN group,both LD and ULD groups demonstrated significantly reduced volume CT dose index(CTDIvol),dose-length product(DLP)and effective dose(ED)(all adjusted P＜0.05).In ULD group,SDCT of white matter in frontal,parietal and temporal lobes were higher than those in CN group,and SDCT of white matter in parietal lobe was also higher than that in LD group(all adjusted P＜0.05).No significant difference of SDCT of gray matter was observed among groups(all P＞0.05).SNR of white matter in parietal and temporal lobes in both LD and ULD groups were lower than those in CN group(all P＜0.05),while no significant difference of SNR of white matter in frontal lobe,nor of gray matter in frontal,parietal and temporal lobes was found among groups(all P＞0.05).CNR of gray and white matter in the frontal,parietal and temporal lobes were not significantly different among groups(all P＞0.05).High consistency of inter-observer subjective scores of CBV maps,CBF maps and Tmax maps(Kappa of 0.623,0.644 and 0.638,respectively)were noticed,which of MTT maps had moderate consistency(Kappa=0.560).No significant difference of intra-obsever subjective scores of CTP pseudo-color images was found among groups(all P＞0.05).CBV,CBF,MTT and Tmax values of gray and white matter in frontal,parietal and temporal lobes were not significantly different among groups(all P＞0.05).Conclusion DLIR algorithm applicated in low radiation dose and reduced contrast agent dosage might ensure imaging quality.

Objective To observe the value of deep learning image reconstruction(DLIR)algorithm in brain CT perfusion(CTP)using a protocol of 70 kVp and 40 ml contrast agent dose.Methods Totally 105 patients with suspected acute ischemic stroke(AIS)were prospectively enrolled and randomly divided into 3 groups,who underwent standard dose CTP scanning with 80 kVp and 150 mA combined with reconstruction as adaptive statistic iterative reconstruction V(ASIR-V)at 50％level(CN group,n=35),low dose(LD)scanning with 70 kVp and 100 mA combined with DLIR reconstruction at the highest level(DLIR-H)(LD group,n=35),or ultra-low dose(ULD)scanning with 70 kVp and 70 mA combined with DLIR-H reconstruction(ULD group,n=35).Radiation doses were compared among 3 groups.CT values and standard deviations(SDCT)of ROI of gray matter and white matter in the frontal,parietal and temporal lobes were measured.Signal-to-noise ratio(SNR)and contrast-to-noise ratio(CNR)between gray and white matter were calculated and compared among groups.Then pseudo-color images of cerebral blood volume(CBV),cerebral blood flow(CBF),mean transit time(MTT)and time to maximum of the tissue residual function(Tmax)were generated.The imaging quality of CTP pseudo-color images was evaluated,and the compatibility of the subjective scores within every kind of CTP pseudo-color images were assessed using Kappa test.Quantitative perfusion parameters were measured and compared among groups.Results Compared with CN group,both LD and ULD groups demonstrated significantly reduced volume CT dose index(CTDIvol),dose-length product(DLP)and effective dose(ED)(all adjusted P＜0.05).In ULD group,SDCT of white matter in frontal,parietal and temporal lobes were higher than those in CN group,and SDCT of white matter in parietal lobe was also higher than that in LD group(all adjusted P＜0.05).No significant difference of SDCT of gray matter was observed among groups(all P＞0.05).SNR of white matter in parietal and temporal lobes in both LD and ULD groups were lower than those in CN group(all P＜0.05),while no significant difference of SNR of white matter in frontal lobe,nor of gray matter in frontal,parietal and temporal lobes was found among groups(all P＞0.05).CNR of gray and white matter in the frontal,parietal and temporal lobes were not significantly different among groups(all P＞0.05).High consistency of inter-observer subjective scores of CBV maps,CBF maps and Tmax maps(Kappa of 0.623,0.644 and 0.638,respectively)were noticed,which of MTT maps had moderate consistency(Kappa=0.560).No significant difference of intra-obsever subjective scores of CTP pseudo-color images was found among groups(all P＞0.05).CBV,CBF,MTT and Tmax values of gray and white matter in frontal,parietal and temporal lobes were not significantly different among groups(all P＞0.05).Conclusion DLIR algorithm applicated in low radiation dose and reduced contrast agent dosage might ensure imaging quality.

An innovative on-site real-time avian influenza virus(AIV)detection method was estab-lished by integratingrecombinase-aided amplification(RAA)with the clustered regularly inter-spaced short palindromic repeats(CRISPR)/CRISPR-associated protein(Cas)system.After analy-zing 120 sequences of the M gene of avian influenza viruses of different subtypes publicly available on NCBI,the RAA primers and crRNA were designed based on the identified highly conserved segment and used for RAA nucleic acid amplification.After the amplified products were transferred to a CRISPR/Cas13a detection system,the fluorescence values were monitored throughout the re-action process to indicate the results.The sensitivity and specificity of the RAA-CRISPR/Cas13a method were validated using gradient dilutions(106-100 copies/μL)of positive plasmids and sev-en other avian viruses.Fifty clinical samples were tested using this method and compared with the national standard fluorescence RT-PCR method.The results indicated that the detection limit for RAA-CRISPR/Cas13a method was 102 copies/μL,a two-fold improvement over the standard RAA.Specificity assay showed the established method only detected AIV with no cross-reactivity with other seven avian viruses.Compared to the national standard fluorescence RT-PCR method,this method exhibited 100％specificity,95.24％accuracy,and 98.00％consistency in detection of clinical samples.In conclusion,a universal and rapid RAA-CRISPR/Cas13a for detection of AIV was established with the capacity of achieving detection within 60 minutes at 37 ℃,which provides a rapid,sensitive,and specific on-site detection method for AIV.

Objective To explore the imaging features, clinical outcome, and prognosis of indeterminate pulmonary nodules (IPN) in patients with high-grade soft tissue sarcoma. Methods A retrospective study of 82 patients with high-grade soft tissue sarcoma who have IPNs. The clinical characteristics, imaging features of IPN, and survival of patients were analyzed with statistical software. Results The IPN size of 82 patients was 6.453±0.864 mm. IPN diameter, shape, density, and nodule discovery interval may be CT imaging features related to malignancy tendency. Age (HR=1.047, 95%CI: 1.007-1.088) and interval between each nodule discovery (HR=3.194, 95%CI: 1.052-9.694) are independent factors that affect the survival of patients with malignant IPN. Conclusion The imaging features of chest CT may provide important guidance for determining the nature and survival prognosis of benign and malignant nodules.

Hydrogels/therapeutic use* ; Tissue Engineering ; Gelatin ; Intervertebral Disc/surgery* ; Methacrylates ; Tissue Scaffolds

Objective:To explore the incidence, clinical characteristics, imaging features, clinical outcome and prognosis of indeterminate pulmonary nodules (IPN) in patients with osteosarcoma.Methods:A total of 69 patients of osteosarcoma with IPN in lung treated in the Bone tumor Center of Eastern Theater General Hospital from January 2011 to January 2021 were collected retrospectively, there were 47 males and 22 females, with a median age of 19 years old (range 7-60 years old). The clinical characteristics including disease-free interval, the chemotherapy response, with recurrence/non-pulmonary, IPN presence before / during / after chemotherapy and imaging features of IPN including number of IPN, location of IPN, density of IPN, boundary clarity of IPN and outcome. The patients were divided into the metastasis pulmonary nodules group and the benign nodules group according to the final outcome of IPN. Further, χ 2 test was performed for comparison of the clinical and imaging characteristics between the two groups. The survival of patients was counted and the correlation between single factor and survival was compared by Kaplan-Meier test, and multivariate survival analyses were performed using Cox proportional hazards regression models. Results:Sixty-nine cases occurred IPN in 211 patients with osteosarcoma, with an incidence of 32.7%. Of the 69 patients, 45 patients (65.2%) with IPN were diagnosed as metastases, and 24 patients (34.8%) with IPN were diagnosed as benign nodules. Follow-up length ranged from 1 to 124 months, with the median follow up time 43 months. To the end of follow-up, 41 patients (59.4%) remained alive and 28 patients (40.6%) had died. The median survival time was 41.0 (20.0, 65.0) months and the median survival time after diagnosis of IPN was 25.0 (10.0, 43.0) months. There were significant differences in lung nodule density ( P<0.001), boundary ( P=0.002), history of recurrence/extra-pulmonary metastasis ( P=0.023) and chemotherapeutic effect ( P<0.001) between the metastasis pulmonary nodules group and the benign nodules group. Multivariate survival analysis showed that chemotherapeutic effect was an independent factor affecting the overall survival of patients [ HR=0.048, 95% CI (0.01, 0.26)]. Boundary definition [ HR=0.12, 95% CI (0.02, 0.93)] and chemotherapeutic effect [ HR=0.06, 95% CI (0.01, 0.29)] were independent factors influencing survival after diagnosis of IPN. Conclusion:Osteosarcoma patients with IPN have a poor prognosis. The poor effect of chemotherapy is an independent risk factor for the overall survival time of those patients and the survival time after diagnosis of IPN. The boundary definition of IPN is an independent risk factor for the survival time after diagnosis of IPN.

Objective:To analyze the value of peritumoral vascular invasion (PVI) on the prognosis of patients with osteosarcoma.Methods:A total of 232 patients with primary osteosarcoma from 2007 to 2016 were retrospectively analyzed, including 142 males and 90 females. The average age was 17.9±8.2 years (range, 3-39 years). There were 22 positive and 210 negative cases of PVI, 94 deaths and 138 survivals. Univariate survival analysis (Log-rank test and univariate Cox regression) was used to evaluate the effects of age, gender, PVI status, tumor location, surgical method, sensitivity to chemotherapy, and chemotherapy regimen on the prognosis of osteosarcoma. The indicators with statistically significant differences were included in the multivariate Cox regression model to finally determine the risk factors affecting the prognosis of osteosarcoma. The relationship between PVI status and 5-year survival and the incidence of recurrence or metastasis was evaluated using the Kaplan-Meier method.Results:All patients were followed up for 7.6±4.5 years (range, 0.1-15 years). The differences in sensitivity to chemotherapy (χ 2=9.52, P=0.002), choice of chemotherapy regimen (χ 2=8.87, P=0.012), choice of surgical modality (χ 2=13.50, P<0.001), tumor metastasis rate (χ 2=8.51, P=0.004) and mortality rate (χ 2=5.39, P= 0.020) of PVI positive group and PVI negative group had statistically significant differences. Univariate survival analysis was performed on 232 patients with osteosarcoma (gender, age, PVI status, site of tumor development, surgical modality, sensitivity to chemotherapy, and chemotherapy regimen). Indicators with statistically significant differences were included in a multifactorial Cox regression model. The results showed PVI positive [5-year survival rate: HR=2.02, 95% CI (1.61, 2.79), P=0.010; 5-year recurrence or metastasis rate: HR=2.25, 95% CI (1.55, 3.14), P<0.001], surgical procedure as amputation [5-year survival rate: HR=1.22, 95% CI (0.94, 1.78), P=0.037; 5-year recurrence or metastasis rate: HR=1.58, 95% CI (1.11, 2.23), P=0.026] and poor sensitivity to chemotherapy [5-year survival rate: HR=2.71, 95% CI (1.84, 3.98), P=0.001; 5-year recurrence or metastasis rate: HR=2.52, 95% CI (1.88, 3.45), P<0.001] was associated with poor prognosis. Kaplan-Meier curve showed that the 5-year survival rate of PVI positive group was 34%, which was lower than 68% of PVI negative group. The 5-year recurrence or metastasis rate was 72% in the PVI negative group, which was significantly higher than 38% in the PVI negative group ( P<0.05). Conclusion:The 5-year survival rate of PVI positive group was lower than that of PVI negative group, and the 5-year recurrence or metastasis rate was higher than that of PVI negative group. The presence of microvascular angiosarcoma plugs infiltrating the peritumoral tissue in surgical specimens of osteosarcoma after neoadjuvant chemotherapy is a useful indicator to assess the prognosis of patients with osteosarcoma.

Objective:To compare outcomes between standardized and misdiagnosis and mistreatment of osteosarcoma.Methods:A retrospective analysis of patients with high-grade osteosarcoma who received appropriate surgical treatment and chemotherapy (299 cases, control group) and those who were misdiagnosed (benign or infective) and received mistreatment (23 cases, study group) between January 2009 and December 2021. Gender, age, first operation mode, recurrence time, recurrence interval, metastasis time, metastasis interval, total survival time (months), survival status in the two group and tumor site reoperation mode in the study group were statistically analyzed. Further, chi-square test was performed for comparison of the clinical between two groups. The survival analysis was performed using Kaplan-Meier test and Log-rank test.Results:All the 322 patients were followed up. In the control group, the average follow-up time was 42 months (1-137 months), the average age was 24 years (3-80 years), male 184 cases, female 115 cases, and limb salvage rate was 85.3% (255/299). Seven patients underwent amputation, and the amputation rate was 17.7% (44/299). The recurrence rate was 8.4% (25/299), the average recurrence interval was 22.8 months (7-36 months), and the metastasis rate was 28.1% (85/299), the average metastasis time was 32.7 months (0-58 months). In the study group, the average of follow-up time was 30 months (9-117 months), the average age was 36 years (5-67 years), 17 males and 6 females. Among them, eleven patients were treated with limb salvage in the second stage, and the limb salvage rate was 47.8% (11/23). Seven patients underwent amputation, and the amputation rate was 30.4% (7/23). The recurrence rate was 26.1% (6/23), the average recurrence interval was 11 months (1-42 months), and the metastasis rate was 43.4% (10/23), the average metastasis time was 20.3 months (1-44 months). The 5-year survival rate was 50.7% in the study group and 56.1% in the control group. There was no significant difference between the two groups (χ 2=0.09, P=0.760). Conclusion:The overall prognosis of patients with high-grade osteosarcoma who receive active treatment after mistreatment is similar to that of patients with standardized treatment, but the recurrence and metastasis rate is higher, the recurrence time is earlier, and the amputation rate is higher.

Objective:To examine the correlation factors of acute appendicitis associated with appendiceal neoplasms.Methods:Consecutive 712 patients with acute appendicitis who treated at Department of General Surgery, Beijing Chaoyang Hospital, Capital Medical University from January 2002 to December 2016 were analyzed retrospectively. There were 314 females and 398 males, aging (42.5±16.2) years (range: 14 to 94 years). Among the 712 cases, 36 patients were diagnosed with acute appendicitis associated with appendiceal neoplasms, the other 676 patients had no appendiceal neoplasm. The patients ′ clinical baseline characteristics and clinical parameters were compared between the two groups. The correlation factors of acute appendicitis associated with appendiceal neoplasms were evaluated by using the univariate (χ 2 test or t test) and multivariate Logistic regression analysis. The area under curve of receiver operating characteristic curves was utilized to evaluate the discriminatory power of the predictive models. Results:According to the univariate analysis, gender, age, body mass index, the duration of chronic right low abdominal pains≥3 months, the frequency of recurrently acute right lower abdominal pain≥2, the frequency of acute right lower abdominal pain, past history of diabetes, hypertension or coronary heart disease, the level of neutrophils and leukocytes preoperatively, stercolith and periappendiceal effusion, and modified Alvarado score were positively correlated with appendiceal neoplasms (all P<0.05). Then four variables were incorporated into the model eventually by multivariate Logistic regression analysis, which were as follows: age (increased per decade) ( OR=2.23, 95% CI: 1.68 to 2.95, P<0.01), gender (female) ( OR=4.21, 95% CI: 1.74 to 10.19, P=0.001), the duration of chronic right low abdominal pains (more than 3 months) ( OR=2.53, 95% CI: 1.01 to 3.37, P=0.048), and modified Alvarado score (decreased per 1 score) ( OR=2.54, 95% CI: 1.87 to 3.34, P<0.01). The area of curve was 0.93 (95% CI: 0.88 to 0.97), which indicated that the model exhibits an excellent ability to discriminate between appendiceal neoplasms and acute appendicitis. Conclusions:The older age, female, the duration of chronic right low abdominal pains, and lower modified Alvarado score are independent correlation factors for acute appendicitis associated with appendiceal neoplasms. Clinicians should be alert for the above clinical characteristics and choose optimal treatment for acute appendicitis associated with appendiceal neoplasms.

Objective:To examine the correlation factors of acute appendicitis associated with appendiceal neoplasms.Methods:Consecutive 712 patients with acute appendicitis who treated at Department of General Surgery, Beijing Chaoyang Hospital, Capital Medical University from January 2002 to December 2016 were analyzed retrospectively. There were 314 females and 398 males, aging (42.5±16.2) years (range: 14 to 94 years). Among the 712 cases, 36 patients were diagnosed with acute appendicitis associated with appendiceal neoplasms, the other 676 patients had no appendiceal neoplasm. The patients ′ clinical baseline characteristics and clinical parameters were compared between the two groups. The correlation factors of acute appendicitis associated with appendiceal neoplasms were evaluated by using the univariate (χ 2 test or t test) and multivariate Logistic regression analysis. The area under curve of receiver operating characteristic curves was utilized to evaluate the discriminatory power of the predictive models. Results:According to the univariate analysis, gender, age, body mass index, the duration of chronic right low abdominal pains≥3 months, the frequency of recurrently acute right lower abdominal pain≥2, the frequency of acute right lower abdominal pain, past history of diabetes, hypertension or coronary heart disease, the level of neutrophils and leukocytes preoperatively, stercolith and periappendiceal effusion, and modified Alvarado score were positively correlated with appendiceal neoplasms (all P<0.05). Then four variables were incorporated into the model eventually by multivariate Logistic regression analysis, which were as follows: age (increased per decade) ( OR=2.23, 95% CI: 1.68 to 2.95, P<0.01), gender (female) ( OR=4.21, 95% CI: 1.74 to 10.19, P=0.001), the duration of chronic right low abdominal pains (more than 3 months) ( OR=2.53, 95% CI: 1.01 to 3.37, P=0.048), and modified Alvarado score (decreased per 1 score) ( OR=2.54, 95% CI: 1.87 to 3.34, P<0.01). The area of curve was 0.93 (95% CI: 0.88 to 0.97), which indicated that the model exhibits an excellent ability to discriminate between appendiceal neoplasms and acute appendicitis. Conclusions:The older age, female, the duration of chronic right low abdominal pains, and lower modified Alvarado score are independent correlation factors for acute appendicitis associated with appendiceal neoplasms. Clinicians should be alert for the above clinical characteristics and choose optimal treatment for acute appendicitis associated with appendiceal neoplasms.