Objective:To measure and analyze the distribution characteristics of the micro-hardness of the middle-upper thoracic vertebrae (T 1-T 10) in the human body. Methods:T 1-T 10 vertebrae from three fresh cadavers were divided into vertebral body area and attachment area. 3 mm specimens were cut by a high-precision slow saw and 11 regions were selected and measured on each vertebrae by a Vickers microhardness tester (cortical bone: 1-9, cancellous bone: 10-11). The micro-hardness distribution of T 1-T 10 vertebrae was recorded and analyzed. Results:A total of 330 measurement areas from 30 vertebrae were measured, and 1 650 hardness values were collected. The average hardness values of the overall cortical bone of the middle-upper thoracic vertebrae of the 3 cadavers were 30.55±5.44 HV, 29.94±4.86 HV, and 29.55±4.36 HV, respectively. The difference among the groups was statistically significant ( F=4.680, P=0.009). The average hardness values of the overall cancellous bone were 27.93±5.61 HV, 28.21±4.96 HV, 27.98±3.94 HV, respectively. There was no significant difference among the groups ( F=0.091, P=0.913). There were statistically significant differences between the hardness values in the attachment area and vertebral body area of each cadaver ( t=7.467, 4.750, 6.621, P<0.001); the hardness of the cancellous bone in the attachment area of each cadaver was higher than that of the cancellous bone in the vertebral body ( t=1.785, 3.159, 3.103, P=0.077, 0.002, 0.003). The distribution of microhardness in 11 measurement areas of 3 cadavers were similar: the hardness of the cortical bone of pedicle, lamina and inferior endplate cortex (1, 2, 7) were higher; the hardness of the cortical bone of upper endplate and peripheral cortex (6, 8, 9) were lower. The distribution patterns of the microhardness in different vertebral segments of the 3 cadavers were similar: The hardness values gradually increased from T 1 to T 10. The vertebra with the largest hardness of the cortical bone was T 8; and the vertebra with the largest hardness of the cancellous bone were T 7, T 7 and T 6, respectively. Conclusion:The hardness of the upper endplate and peripheral cortex was low, which could disperse the load to protect the fragile cancellous bone. The hardness of the pedicle was the highest. The hardness of the cortical bone was higher than that of the cancellous bone, and the values of different segments gradually increased from top to bottom, which may be related to the physiological and anatomical morphology, and the gradual increase of the load of muscle force and body weight.

Objective To explore the application of nucleic acid test in the diagnosis of HIV western blotting (WB) indeterminate and negative samples. Methods A total of 2 518 HIV samples to be confirmed were collected from the Hubei HIV Confirmation Center Laboratory from 2014 to 2022. The results of follow-up antibody test and nucleic acid test of WB indeterminate and negative samples were analyzed, and the diagnostic rate, sensitivity, specificity and coincidence rate of the two detection strategies were compared. Results There were totally 133 indeterminate or negative samples by WB test. Of the 99 indeterminate samples , 76 (76.77%) had nucleic acid test results >5000 copies/mL. 40 cases were followed up, of which 33 cases (82.50%) turned positive and 7 (17.50%) were still uncertain. Of the 7 samples with 20~5000 copies /mL (7.07%), 2 cases were followed up and both turned positive during the follow-up. 1 case (1.01%) with nucleic acid <20 copies/mL turned positive during follow-up. Among the 34 WB negative samples, 15 cases (45.45%) were > 5 000 copies/mL, 9 of which were seroconversion. The diagnostic rates of ^“antibody confirmation^” and ^“nucleic acid test^” were 96.78% (2 437/2 518) and 99.60% (2 508/2 518), respectively. The sensitivities were 98.02% (2 430/2 479) and 99.88% (2476/2 479), and the specificities were 78.13% (25/32) and 100.00 % (32/32), respectively. The coincidence rates were 97.77% (2 455/2 511) and 99.88% (2 508/2 511), respectively. Conclusion Nucleic acid supplemental test strategy has high diagnostic rate, sensitivity, specificity and coincidence rate. WB indeterminate and negative samples can be diagnosed as early as possible through nucleic acid supplemental testing.

Objective To analyze HIV-1 drug resistance gene mutations in AIDS patients who failed first-line antiviral therapy in Hubei Province from 2017 to 2018, and to provide references for clinical treatment. Methods Plasma samples of HIV patients who had received first-line antiviral treatment for more than 12 months and had a viral load greater than 103 copies / ml were collected in Hubei Province, and drug resistance genotypes were detected. The prevalence and characteristics of drug resistance were analyzed. Results A total of 198 patients were selected, and 182 target gene sequences were successfully detected. The gene subtypes were mainly CRF01_{_}AE, with a total drug resistance rate of 69.23%. The proportion of NRTIs, NNRTIs and PIs resistance mutations was 46.15%, 65.38% and 0.55%, respectively. The occurrence of cross resistance mutations of NRTIs and NNRTIs reached 40.66%. The mutation sites related to NRTIs were mainly M184V and K65R, while the mutation sites related to NNRTIs were mainly V179D, K103N and Y181C. There was only one case of PIs related mutation at the site of M46I. Conclusion HIV-1 genotyping demonstrated a high proportion of drug resistance in the HAART failure population in Hubei Province, and multi-drug resistance occurred frequently. It is necessary to strengthen the monitoring of drug resistance, implement timely adjustments to antiviral treatment programs, and reduce the occurrence and spread of drug-resistant strains.