It is common practice to diagnose spondylolysis with oblique radiographsof the lumbar spine although antero-posterior and lateral radiographs aretaken routinely for patients with lower back pain. The author has acquiredmore understanding about the radiographic features in the antero-posteriorand lateral views through a study of radiographs taken from artificial imi-tative specimens of spondylolysis. Eleven typical features have been identi-fied and with their aid the plain radiographs of 169 cases of spondylolysishave been analyzed. The results have been compared with those obtainedfrom oblique views. The percentage of diagnoses achieved by plane filmshas been determined at 89.1% with the antero-posterior view, 81.6% with thelateral view and 93.1% with the oblique views. If spondylolysis can bediagnosed with antero-posterior and lateral radiographs alone, the diagnosiswill be more expeditious and economical.

An investigation was made on 555 ranking Chinese Athletes engaged in 26 different sports and events. The type and incidence of vertebral deformity were counted. The incidence of low back pain as a result of the deformity was also counted. The relationship between low back pain and deformity was analyzed and the result was compared with 657 athletes who came to our clinic for treatment. The results were as follows:1. The incidence of secondary injury and illness in athletes with vertebral deformity was high. The incidence of spondylolysis in athletes with vertebral deformity was still higher. Athletes with serious deformity were liable to injury of bone, while those with light deformity were likely to develop injury of soft tissue.2. The pain of those with the deformity was mainly caused by secondary injury and illness but in a few of them the pain was the result of the vertebral deformity itself.3. To prevent the pain of vertebral deformity, it is important to prevent the development of secondary inry and illness.

Objective To express virus-like particles(VLP) of enterovirus 71 (EV71) in Han-senula polymorpha.Methods The coding sequences of P1 and 3CD genes of EV71 were optimized accord-ing to codon usage bias of Hansenula polymorpha for achieving high expression , and then cloned into the ex-pression vector PMV of Hansenula polymorpha .The recombinant expression vector PMV-P1-3CD was trans-formed into Hansenula polymorpha AU 0501 .The transformants were stably cultured in selective medium (Yeast Nitrogen Base) and screened for strains with positive P1 and 3CD genes by PCR.Then an induced cultivation on the recombinant strains were performed in a medium supplemented with methanol to a final concentration of 1.0%and the expressed products were analyzed by SDS-PAGE and Western blot assays to select high expression strains .The high expression strains were cultured in 30 L fermentor and its fermenta-tion products were analyzed by electronic microscope after purification .Results EV71 recombinant expres-sion strains were successfully constructed .The results of SDS-PAGE showed that the expressed products had obvious VP3, VP1, VP0 protein bands with molecular weights of 26×103, 33×103 and 35×103, respective-ly, which were consistent with the expected molecular weight of the fusion proteins .Western blot demonstra-ted that the expressed products could be specifically recognized by the polyclonal antibody against EV 71-VP1 at 33 ×10 3 , indicating its high immunoreactivity .ELISA confirmed that the expression level of EV 71 fermen-tation products was reached to 200 mg/L.Electronic microscope analysis showed that the VLP of recombi-nant EV71 were 24-30 nm in diameter with normal structure .Conclusion The virus-like particles of human enterovirus 71 are successfully expressed in Hansenula polymorpha , which provides a foundation for the fur-ther development of EV 71 VLP vaccine .

Objective:To investigate the risk factors for hemorrhagic transformation (HT) after intravenous thrombolysis (IVT) in patients with acute ischemic stroke (AIS), and the predictive value of Neutrophil to lymphocyte ratio (NLR).Methods:Consecutive patients with AIS received IVT in Zhengzhou People’s Hospital from January 2021 to December 2022 were retrospectively enrolled. HT was defined as no intracranial hemorrhage was found on the first imaging examination after admission, and new intracranial hemorrhage was found on the imaging examination 24 h after IVT or when symptoms worsened. sHT was defined as HT and the National Institutes of Health Stroke Scale (NIHSS) score increased by ≥4 compared to admission or required surgical treatment such as intubation and decompressive craniectomy. The baseline clinical and laboratory data of the patients were collected, and NLR, lymphocyte to monocyte ratio (LMR), and platelet to neutrophil ratio (PNR) were calculated. Multivariate logistic regression analysis was used to identify the independent predictors of HT and sHT, and receiver operating characteristic (ROC) curve was used to analyze the predictive value of NLR for HT and sHT after IVT. Results:A total of 196 patients were included (age 65.37±13.10 years, 124 males [63.3%]). The median baseline NIHSS score was 4 (interquartile range: 2-10). Twenty patients (10.2%) developed HT, and 12 (6.1%) developed sHT. Univariate analysis showed that there were statistically significant differences in age, baseline NIHSS score, creatinine, NLR, and stroke etiology type between the HT group and the non-HT group (all P<0.05); there were statistically significant differences in age, NLR, PNR, creatinine, baseline NIHSS score, and stroke etiological type between the sHT group and the non-sHT group (all P<0.05). Multivariate logistic regression analysis showed that NLR was an independent predictor of HT (odds ratio [ OR] 1.375, 95% confidence interval [ CI] 1.132-1.670; P=0.001) and sHT ( OR 1.647, 95% CI 1.177-2.304; P=0.004) after IVT. The ROC curve analysis showed that the area under the curve for predicting HT by NLR was 0.683 (95% CI 0.533-0.833; P=0.007), the optimal cutoff value was 5.78, the sensitivity and specificity were 55.0% and 84.1%, respectively. The area under the curve for predicting sHT by NLR was 0.784 (95% CI 0.720-0.839; P=0.001), the optimal cutoff value was 5.94, the sensitivity and specificity were 66.67% and 84.24%, respectively. Conclusions:A higher baseline NLR is associated with an increased risk of HT and sHT after IVT in patients with AIS, and can serve as a biomarker for predicting HT and sHT after IVT.