Objective:To investigate the dose characteristics of the Zeiss INTRABEAM system in air and water, providing dose reference for electronic brachytherapy.Methods:A Monte Carlo program was used to establish a three-dimensional model of a miniature X-ray source vacuum drift tube and a 4 cm spherical applicator. The process of electron beam bombardment on a gold target to generate X-rays was simulated, and parameters such as photon fluence spectrum, percentage depth dose, and half-value layer were calculated. Additionally, the radial dose uniformity in water was measured.Results:The average energy of X-rays at 3 cm in air was 20.8 keV, with a half-value layer of 0.08 mm Al. Under the influence of the applicator, the spectrum becomes hardened, with axial and radial average energies of 28.7 and 29.0 keV, respectively. In water, the percentage depth dose (PDD) curve follows an inverse cubic decay with depth, indicating strong dose concentration and rapid fall-off in near-field irradiation. The radial dose uniformity in water exceeded 99.5%.Conclusions:The INTRABEAM device emits low-energy X-rays characterized by shallow penetration depth, and concentrated dose delivery. Its highly uniform dose distribution ensures comprehensive coverage of the target area, making it particularly suitable for treating superficial tumors and for intraoperative radiotherapy at close range.

Objective:To investigate the dose characteristics of the Zeiss INTRABEAM system in air and water, providing dose reference for electronic brachytherapy.Methods:A Monte Carlo program was used to establish a three-dimensional model of a miniature X-ray source vacuum drift tube and a 4 cm spherical applicator. The process of electron beam bombardment on a gold target to generate X-rays was simulated, and parameters such as photon fluence spectrum, percentage depth dose, and half-value layer were calculated. Additionally, the radial dose uniformity in water was measured.Results:The average energy of X-rays at 3 cm in air was 20.8 keV, with a half-value layer of 0.08 mm Al. Under the influence of the applicator, the spectrum becomes hardened, with axial and radial average energies of 28.7 and 29.0 keV, respectively. In water, the percentage depth dose (PDD) curve follows an inverse cubic decay with depth, indicating strong dose concentration and rapid fall-off in near-field irradiation. The radial dose uniformity in water exceeded 99.5%.Conclusions:The INTRABEAM device emits low-energy X-rays characterized by shallow penetration depth, and concentrated dose delivery. Its highly uniform dose distribution ensures comprehensive coverage of the target area, making it particularly suitable for treating superficial tumors and for intraoperative radiotherapy at close range.

Objective To establish a fluorescent assay for rapid detection of Plasmodium falciparum based on recombinaseaided amplification (RAA) and CRISPR-Cas12a system,and to preliminarily evaluate the diagnostic efficiency of this system.. Methods The 18S ribosomal RNA (rRNA) gene of P. falciparum was selected as the target sequence, and three pairs of RAA primers and CRISPR-derived RNA (crRNA) were designed and synthesized. The optimal combination of RAA primers and crRNA was screened and the reaction conditions of the system were optimized to create a fluorescent RAA/CRISPR-Cas12a system. The plasmid containing 18S rRNA gene of the P. falciparum strain 3D7 was generated, and diluted into concentrations of 1 000, 100, 10, 1 copy/μL for the fluorescent RAA/CRISPR-Cas12a assay, and its sensitivity was evaluated. The genomic DNA from P. vivax, P. malariae, P. ovum, hepatitis B virus, human immunodeficiency virus and Treponema pallidum was employed as templates for the fluorescent RAA/CRISPR-Cas12a assay, and its specificity was evaluated. Fifty malaria clinical samples were subjected to the fluorescent RAA/CRISPR-Cas12a assay and nested PCR assay, and the consistency between two assays was compared. In addition, P. falciparum strain 3D7 was cultured in vitro. Then, the culture was diluted into blood samples with parasite densities of 1 000, 500, 200, 50, 10 parasites/μL with healthy volunteers’ O-positive red blood cells for the RAA/CRISPR-Cas12a assay, and the detection efficiency was tested. Results The Pf-F3/Pf-R3/crRNA2 combination, 2.5 μL as the addition amount of B buffer, 40 min as the RAA reaction time, 37 °C as the reaction temperature of the CRISPR-Cas12a system were employed to establish the fluorescent RAA/CRISPR-Cas12a system. Such a system was effective to detect the plasmid containing 18S rRNA gene of the P. falciparum strain 3D7 at a concentration of 1 copy/μL, and presented fluorescent signals for detection of P. falciparum, but failed to detect P. ovum, P. malariae, P. vivax, T. pallidum, hepatitis B virus or human immunodeficiency virus. The fluorescent RAA/CRISPR-Cas12a system and nested PCR assay showed completely consistent results for detection of 50 malaria clinical samples (kappa = 1.0, P < 0.001). Following 6-day in vitro culture of the P. falciparum strain 3D7, 10 mL cultures were generated and the fluorescent RAA/CRISPR-Cas12a system showed the minimal detection limit of 50 parasites/μL. Conclusion The fluorescent RAA/CRISPR-Cas12a system is rapid, sensitive and specific for detection of P. falciparum, which shows promising value for rapid detection and risk monitoring of P. falciparum.

Objective To study the protective effect of propofol on post-hypoxic injury of car-diomyocytes induced during hyperglycemia.Methods Rat primary H9C2 cardiomyocytes were cul-tured and the model of hypoxia-reoxygenation (HR)was constructed.The cells were assigned to the following groups:normal control group (group NC),high glucose group (group HG)and HR under high glucose group (group GR),and propofol treated groups in which cells were treated with various concentrations (12.5,25,50,and 100 μmol/L)of propofol (i.e.,groups P12.5,P25,P50 and P100)and the solvent DMSO group (D100 group,DMSO at 100 μmol/L)respectively.(CK-MB), cardiac troponin I (cTnI),lactate dehydrogenase (LDH),mitochondrial activity,intracellular ATP content and intracellular oxidation of the cells were compared.Results Compared with the groups NC and HG,the cell viability was significantly decreased,the concentration of LDH and MDA,relative concentration of CK-MB and cTnI increased significantly,and the activity of T-SOD,mitochondria and the relative concentration of ATP decreased significantly in the other groups (P<0.05).Com-pared with the group GR,the cell activity increased significantly,the concentration of LDH and MDA ,relative concentration of CK-MB and cTnI were Significantly decreased,and the activity T-SOD, mitochondrial and relative concentration of ATP increased significantly in the groups P12.5,P25 and P50 (P<0.05).Compared with the group P25,the cell viability decreased significantly,the concen-trations of LDH,MDA,relative concentrations of CK-MB and cTnI increased significantly,and the activity of T-SOD and mitochondria and relative concentration of ATP were significantly reduced in the groups P50,P100 and D100 (P<0.05).Conclusion Propofol can reduce the damage of myocar-dial cells by reducing the damage of mitochondria.

Objective To investigate the most appropriate surgical methods,different surgical modes of osmidrosis and their clinical effi-cacy were observed. Methods Clinical data was collected from 200 cases of axillary osmidrosis from January 2011 to July 2013. These cases were divided into four groups of the traditional group,minimally invasive group,RF pen-frequency electric cautery group and improved curet-tage group. Results The traditional group(80 cases) has an average healing period of 18. 7 days for operative incision including 78 cured cases(97. 5%)and 2 significant improved cases(2. 5%). The minimally invasive group(60 cases)has an average healing time of 8. 6 days, among which there are 3 cured cases(5%),8 significant improved cases(13. 3%),16 improved cases(26. 7%),4 cases(6. 7%)with weak curative effect and 29 failed cases(48. 3%). In the RF pen-frequency electric cautery group(30 cases),there are 5 significant improved ca-ses(16.7%),8improvedcases(26.7%)and17failedcases(56.6%).Theimprovedcurettagegroup(30cases)withanaverageincision healingtimeof9.8dayscontains28curedcases(93.3%)and2significantimprovedcases(6.7%). Conclusion Thetraditionalgroup shows the best curative effect,nevertheless the incision needs a considerably amount of time to recover. The patients under the treatment of minimally invasive surgery or RF pen-frequency electric cautery can recover in short time but recrudescence always occur. The improved cu-rettage method,which is effective and safe,combines the advantages of traditional surgery and minimally invasive surgery. However,large scar left from this method still remains as its major disadvantage but the overall curative effect is satisfactory. The improved curettage is proved to be the most appropriate method for axillary osmidrosis.