Objective To present and discuss beam characteristics of the first Mevion S250i gantry-mounted accelerator pencil beam scanning proton therapy system in China.Methods The output dose was measured using a parallel-plate ionization chamber.The integrated depth dose was measured with a large-radius Bragg peak ionization chamber,covering 19 energy levels ranging from 227 MeV to 28 MeV,to analyze the proton beam characteristics.The spots in the air were measured with Phoenix flat panel detector on the beam central axis,and the precision of the delivery position was verified by measuring the multi-spot beam map.The interleaf leakage and penumbra reduction of adaptive aperture were measured to characterize its performance.Results The proton system was calibrated for a maximum energy of 227 MeV,with a(10×10)cm2uniform field delivering 1 Gy dose at a depth of 5 cm underwater.The system effectively modulated the proton beam range to the patient's surface,maintaining a constant 80%-80%Bragg peak width of 8.6 mm at all energy levels.The spot size of the highest energy beam at the isocenter was about 4 mm in the air,and the spot delivery position error was less than 1 mm.The interleaf leakage rate of the adaptive aperture for the highest energy beam was below 1.5%,and the penumbra was significantly reduced.Conclusion Mevion S250i proton therapy system demonstrates unique design and beam characteristics,which is reflected in the Bragg peak shape,spot size variation with energy,and penumbra sharpening of adaptive aperture;and these differences should be considered in treatment planning system modeling and planning for precision treatment.

Objective:To measure and assess relevant radiation doses at the radiotherapy site of the first domestic single-vault proton therapy system.Methods:The radiation levels of the therapy system during and after beam irradiation were measured, and annual effective doses were assessed for personnel at the site.Results:During beam irradiation, the highest radiation dose was detected at the shielded door of the equipment floor, with a gamma radiation level of 2.140 μSv/h and a neutron radiation level of 0.850 μSv/h. Neutron radiation disappeared immediately once the beams stopped. In contrast, the radiation activated originated mostly from gamma rays. A longer time after beams stopped was associated with lower induced radiation intensity at the same location. Furthermore, a farther distance from the irradiated object corresponded to lower induced radiation intensity at the same time. The assessment result reveal that the annual effective doses to the personnel were at the safe level, with physicists exposed to the highest dose of 2.138 mSv.Conclusions:The radiation level at the studied proton therapy site meets the safety requirement, and the treatment can be performed safely at this site.

Objective:To investigate the effect of ultrasound monitoring of inferior vena cava collapse index (IVC-CI) guiding fluid replacement on circulation in elderly patients during induction of general anesthesia.Methods:A total of 71 elderly patients who underwent elective surgery under general anesthesia and tracheal intubation at Hunan Provincial People′s Hospital from April 2021 to September 2022 were randomly divided into control group (35 cases) and observation group (36 cases) using a random number table method. Before anesthesia, both groups of patients underwent IVC ultrasound examination and calculated the IVC-CI value. For patients with IVC-CI≥40%, the observation group was given 8 ml/kg of crystal solution before anesthesia induction, while the control group was not treated. The incidence of hypotension, the use of vasoactive drugs, and the total infusion volume from anesthesia induction to skin incision were recorded in two groups. Mean arterial blood pressure (MBP), heart rate (HR), oxygen saturation (SpO 2), cardiac index (CI), and cardiac volume variability (SVV) before anesthesia (T 0), 5 min after induction (T 1), 1 min after tracheal intubation (T 2), 5 min after tracheal intubation (T 3), 10 min after tracheal intubation (T 4), and 1 min before skin incision (T 5) were recorded and compared between the two groups. Results:The incidence of hypotension (27.8% vs 60.0%) and utilization rate of vasoactive drugs (25.0% vs 48.6%) in the observation group were lower than those in the control group, and the total infusion volume during anesthesia induction was higher than that in the control group, with statistical significance (all P<0.05). SVV, CI and MBP at T 1, T 3, T 4 and T 5 were significantly different from those at T 0 in the control group ( F=3.85, 14.66, 3.96, all P<0.05). SVV, CI and MBP at T 1, T 3, T 4 and T 5 in the observation group were significantly different from those at T 0 ( F=3.51, 13.20, 4.35, all P<0.05). There was no significant difference in SVV, CI, MBP, HR and SpO 2 between 2 groups (all P>0.05). Conclusions:For the elderly patients with preoperative IVC-CI≥40%, pre-filling with 8ml/kg crystal solution before anesthesia induction can significantly reduce the incidence of hypotension and the utilization rate of vasoactive drugs in the elderly patients during anesthesia induction.

Osteoporotic thoracolumbar fracture in the elderly will seriously reduce their quality of life and life expectancy. For osteoporotic thoracolumbar fracture in the elderly, spinal reconstruction is necessary, which should comprehensively consider factors such as the physical condition, fracture type, clinical characteristics and osteoporosis degree. While there lacks relevant clinical norms or guidelines on selection of spinal reconstruction strategies. In order to standardize the concept of spinal reconstruction for osteoporotic thoracolumbar fracture in the elderly, based on the principles of scientificity, practicality and progressiveness, the authors formulated the Clinical guideline for spinal reconstruction of osteoporotic thoracolumbar fracture in elderly patients ( version 2022), in which suggestions based on evidence of evidence-based medicine were put forward upon 10 important issues related to the fracture classification, non-operative treatment strategies and surgical treatment strategies in spinal reconstruction after osteoporosis thoracolumbar fracture in the elderly, hoping to provide a reference for clinical treatment.

OBJECTIVE: To investigate the effect of vitamin D on microRNA-21(miR-21) expression and migration and invasion of human placental trophoblast cells. METHODS: The changes in the expression of miR-21 were detected using RT-qPCR in HTR-8/SVneo cells following stimulation by vitamin D at different doses for 24, 48 and 72 h.HTR-8/SVneo cells transfected with miR-21 mimic or inhibitor with or without vitamin D treatment were examined for changes in cell migration and invasion abilities using Transwell assay, and Western blotting was used to detect protein expressions of E-cadherin, fibronectin, and MMP9. RESULTS: Vitamin D obviously inhibited the expression of micoRNA-21 in HTR-8/SVneo cells in a concentration-and time-dependent manner.Transfection with the miR-21 mimic significantly inhibited the migration and invasion of HTR-8/SVneo cells, and this inhibitory effect was abolished by treatment with vitamin D; transfection with miR-21 inhibitor obviously promoted the migration and invasion of HTR-8/SVneo cells, and these effects were not significantly affected by vitamin D treatment. CONCLUSIONS Vitamin D may promote trophoblast cell migration and invasion to accelerate the development of preeclampsia by down-regulating the expression of miR-21.
Cell Movement ; Female ; Humans ; MicroRNAs ; genetics ; Placenta ; Pre-Eclampsia ; Pregnancy ; Trophoblasts ; Vitamin D

Objective To observe the changes of arm equilibrium pressure (Parm) in different occlusion time,the reference range of Parm in hemodynamic stable patients,and to explore the relationship between Parm and systemic hemodynamic parameters.Methods Mechanically ventilated postoperative abdominal surgery patients who admitted to ICU with stable hemodynamic status were enrolled.After hemodynamic data were recorded,arm stop-flow maneuvers were performed to measure Parm.At 10,20,30,40,50,60 seconds after occlusion,arterial pressure were measured twice within 5 minutes and recorded as the average value.Results Thirty patients were included.The Parm decreased gradually with the prolongation of the occlusion time.The value was not stable within 60 s,but the reducing extent was not obvious after 40s.The 95％ reference range of Parm 30 S was 23-44 mmHg(1 mmHg =0.133 kPa) and Parm 60 S was 19--35 mmHg.Parm at 30 s and 60 s were positively correlated with systolic arterial pressure,diastolic arterial pressure,mean arterial pressure,central venous pressure (all P ＜ 0.001),but not heart rate and pulse pressure.Linear regression analysis showed that Parm at 10 s,20 s,30 s only had linear correlation with diastolic arterial pressure (10 s,β =0.504,P =0.001;20 s,β =0.297,P =0.005;30 s,β =0.231,P =0.015),and Parm at 40 s,50 s,60 s were linear correlation with diastolic arterial pressure (40 s,β =0.220,P =0.004;50 s,β =0.210,P =0.004;60 s,β =0.213,P =0.004) and central venous pressure (40 s,β =0.516,P =0.018;50 s,β =0.513,P =0.01;60 s,β =0.472,P =0.023).Conclusion In mechanically ventilated postoperative abdominal surgery patients with stable hemodynamic status,Parm decreases when occlusion time is prolonged,which is not stable within 60 s occlusion.Arterial blood pressure and central venous pressure are positively correlated with Parm.

There have been many reports on berberine (BBR) effect of the inhibition on gut bacteria,but more from the protein level.In view of the preference of BBR for DNA binding,we here investigated the expression of BBR from the transcriptional expression level of the gene.The results showed that BBR had a higher affinity for UP element of Escherichia coli (E.coli) gene,and the transcription initiation region of this element contained TATA base sequence.The expression of genes sulA,recA and 16S which contain the genes of the UP element regulatory elements in the upstream of the promoter could be suppressed by BBR,and the expression of lpxC,secG and mutT which did not contain the genes of the UP element regulatory elements in the upstream of the promoter could not be inhibited by BBR.It is shown that the TATA sequence is the target of BBR.This result provides a new perspective for exploring the effect of BBR's inhibition of microbiota from gene transcription.

Berberine (BBR) is known as a classic drug for intestinal infection treatment.BBR inhibits intestinal bacteria,which is the core of its role in the treatment of intestinal infection.With the survival of local intestinal bacteria and its related metabolites on the physiological and pathological functions of the body continue to recognize the impact of it,more and more literatures have presented the effect of BBR through the impact of intestinal bacteria on the body glycol-lipid metabolism,even brain function.This allows us to re-understand the pathophysiology of BBR in inhibiting gut microbiome.In this paper,the antibacterial activity of BBR was reviewed and analyzed.The possible molecular target of BBR was analyzed according to the characteristics of prokaryotes gene expression,which was helpful to the in-depth study of BBR on intestinal bacteria.Thus,a more comprehensive understanding of the pharmacological effects of BBR is given.

Objective:To explore the multi-dimensional method of medical equipment management based on comprehensive index assessment, and improve quality of medical equipment management. Methods: This essay proposed a comprehensive-index-analysis medical equipment management approach within hospital theoretic work and medical equipment management. Equipment management and project application in each clinical department were treated as evaluation criteria which conducted a multi-equality index for medical equipment operation management, using the pattern of quantitative substitute qualitative method.Results: The new method helps to quantize ability of clinical department, equipment utility and management. It refers to scientific equipment management data after procurement, which reflects differences between each department and equipments. Moreover, it helps to prevent blind procurement effectively by ranking department earning capacity.Conclusion: The new method is benefit for equipments’ evaluation and to provide reference for managers in decision-making.

This article was aimed to study the impact on substance and energy metabolism by chemical split fractions of Mori Cortex among hypoglycemic diabetic mouse model, in order to explain the new hypothesis of the science connotation in nature and flavor of traditional Chinese medicine (TCM). Male Kunming mice were intraperitoneally injected with a large dose of streptozotocin (STZ) (170 mg·kg-1) to establish type 1 diabetes mellitus mouse model. Medication was given consecutively for four weeks. The enzyme-linked immunesorbent assay (ELISA) was used to detect glucosekinase (GCK), glycogen phosphorylase (PYGL), pyruvate dehydrogenase (PDH), α-ketoglutarate dehydrogenase (α-KGDHC), phosphoglycerate kinase (PGK), acetyl coenzyme A (acetyl-CoA), adenylate kinase (ADK), fumarase (FUM), cytochrome C reductase (CCR), cytochrome C oxidase (COX) and other indicators. Enzymatic detection was used to determine the content of ATP coenzyme (ATPs), the content and ratio of NAD and NADH, the content of myocardial cell Na+-K+ ATP enzyme, as well as the content of ATP and ADP. The results showed that in the model group, the expression of PYGL was increased; and the expressions of GCK and PDH were decreased. It prompted that the source of glucose increased and the expelling of glucose decreased. The glucose level was increased. The COX expression was reduced and the respiratory chain was blocked. It regulated oxidative phosphorylation and the substrate phosphorylation level. It upregulated the expression of CCR, ATPs, NAD+, PGK, α-KGDHC and ADK. However, the expression of FUM was decreased. The activity of Na+-K+ ATPase was decreased significantly. At last, the metabolic disorders appeared. Mori Cortex aqueous extracts and the chemical split fractions significantly increased the GCK and PDH level in substance metabolism among diabetic mice. The levels of PYGL, α-KGDHC, PGK and acetyl-CoA were decreased (P < 0.05, or P <0.01). Meanwhile, it increased ATP and FUM, myocardial cell Na+-K+ ATP enzyme, and COX level in the energy metabolism (P < 0.05). It decreased the level of NAD+, CCR and ATPs (P < 0.05, or P <0.01). It was concluded that both the aqueous extracts and chemical split fractions of Mori Cortex can effectively improve the substance and energy metabolism disorders of diabetic mouse model. This effect may be related to the cold nature of Mori Cortex.