Objective:To investigate the dosimetric characteristics of intensity modulated proton therapy (IMPT) and photon volumetric modulated arc therapy (VMAT) in typical head and neck malignant tumors.Methods:Three types of typical head and neck tumors (nasopharyngeal carcinoma, parotid gland carcinoma, laryngeal carcinoma) treated at Shandong Cancer Hospital and Institute from December 2023 to December 2024 were taken as research subjects. IMPT and VMAT radiotherapy plans were created according to clinical prescription requirements of target and organs at risk limits respectively. The conformity index (CI), homogeneity index (HI) and gradient index (GI) for target coverage of two radiotherapy plans were evaluated for 3 patients, as well as the dosimetric indicators of organs at risk.Results:The CI of IMPT for nasopharyngeal carcinoma, parotid gland carcinoma and laryngeal carcinoma were 0.70, 0.72 and 0.67, respectively. The HI were 0.11, 0.08 and 0.08, respectively. The GI were 3.08, 2.49 and 3.75, respectively. The CI of VMAT plans were 0.77, 0.82 and 0.91, respectively. The HI were 0.12, 0.10 and 0.04, respectively. The GI were 3.67, 2.63 and 3.45, respectively. The results showed that CI of IMPT plan was slightly lower than that of VMAT plan, and HI of IMPT plan was comparable to that of VMAT plan, the GI of the IMPT plan for patients with nasopharyngeal carcinoma and parotid gland carcinoma was lower than that of the VMAT plan, and the GI of the IMPT plan for patient with laryngeal carcinoma was higher than that of the VMAT plan, and all were within the clinically acceptable range. The IMPT plan has demonstrated significant dose advantages in the treatment of nasopharyngeal carcinoma, parotid gland carcinoma and laryngeal carcinoma. For patient with nasopharyngeal carcinoma, the IMPT plan reduced the D max of the left and right crystals by 54.1% and 50.4%, respectively, compared to VMAT plan, and reduced the D mean of the oral and laryngeal tissues by 40.5% and 49.6%, respectively. For patient with parotid gland carcinoma, IMPT plan reduced the D max of the brainstem and spinal cord by 66.2% and 40.5%, respectively, compared to VMAT plan. For patient with laryngeal carcinoma, IMPT reduced spinal cord D max by 77.0%, while thyroid cartilage D mean increased by 8.0% compared to VMAT plan. For the additional dose in the patients' body, taking the absolute volumes occupied by the prescribed dose areas of 10%, 30%, and 50% in the patients' body as examples, IMPT plan of nasopharyngeal carcinoma patient decreased by 29.7%, 29.6%, and 34.9% compared to VMAT plan, respectively. IMPT plan of parotid gland carcinoma patient decreased by 61.0%, 39.7%, and 17.4% compared to VMAT plan, respectively. IMPT plan of laryngeal carcinoma patient decreased by 63.9%, 31.7%, and 4.1% compared to VMAT plan, respectively. Conclusions:Compared with VMAT plan, IMPT plan can effectively reduce the irradiation dose of most organs at risk near the target of head and neck tumors, but the dose of string organs close to the target area may be higher, which needs attention.

Background ¹³⁷Cs in atmospheric aerosol is the product of past nuclear weapon tests and nuclear accidents. When ¹³⁷Cs is released into the atmosphere, it will deposit in dry land and marine environment, causing pollution of soil surface, water, agricultural products, and animal byproducts, and affecting public health. Objective To identify the variation pattern of ¹³⁷Cs activity concentration in aerosol and its correlation with dust concentration in Beijing area from 2017 to 2020. Methods A total of 958 aerosol samples were collected from November 1, 2017 to June 30, 2020 in Beijing with a high volume air sampler at a sampling flow rate about 600 m³·h⁻¹ and a collection time for each sample about 24 h. The activity concentration of ¹³⁷Cs in the aerosol samples was determined with a low-background high-purity germanium γ spectrometer. The dust concentration was calculated using the difference in the mass of the aerosol filter before and after sampling. The detection rate of ¹³⁷Cs and dust concentration in different seasons were compared. Spearman rank correlation test was used to analyze the correlation between ¹³⁷Cs activity concentration and dust concentration. Results From 2017 to 2020, the ¹³⁷Cs activity concentrations of 33 from 958 aerosol samples in Beijing were above the minimum detectable activityconcentration, the overall detection rate of ¹³⁷Cs was 3.4%, and the activity concentration ranged from 1.86 to 45.53 μBq·m⁻³, with a median value of 4.85 μBq·m⁻³. The detection rate of ¹³⁷Cs was highest in spring, followed by autumn, and lowest in winter and summer (8.4%, 3.0%, 1.1%, and 0.5%, respectively). The dust concentration ranged from 0.03 to 1.55 mg·m⁻³, with an average value of 0.18 mg·m⁻³. There was a statistically significant difference in the dust concentrations in spring, summer, autumn, and winter (F=45.51, P<0.05), and the highest value was 0.24 mg·m⁻³ in spring (P<0.05). The ¹³⁷Cs activity concentration was positively correlated with the dust concentration (P<0.05). Conclusion The ¹³⁷Cs activity concentration in aerosol in Beijing from 2017 to 2020 fluctuates within the range of background level, and its activity concentration is highest in spring, followed autumn, and lowest in summer and winter.

Objective:To observe the therapeutic effect of vibrating the abdomen on anorexia model rats,as well as its effects on cholecystokinin octapeptide(CCK-8)and motilin(MTL)in the peripheral blood. Methods:Forty young rats were randomly divided into a normal group(n=10)and a modeling group(n=30).Rats in the normal group were fed common feed.The anorexia model was established by the etiological simulation method in the modeling group,and these rats were further randomly divided into a drug group,a vibrating abdomen group,and a model group 3 weeks after the anorexia model was induced,with 10 rats in each group.The drug group was given Jian Wei Xiao Shi Pian by intragastric administration at a dose of 0.72 g/(kg·bw)(0.72 g drug was dissolved in 10 mL purified water).The normal group and the model group were given purified water once a day in the morning.The vibrating abdomen group was treated with vibrating the abdomen once a day for 21 times.The body mass,food intake,serum CCK-8,MTL,gastrin(GAS),neurotensin(NT)levels,and the intestinal propulsion rate of rats in each group were measured. Results:Compared with the model group,the body mass,food intake,serum MTL and GAS levels,and the small intestine propulsion rate increased significantly,and the serum CCK-8 and NT levels,the gastric residual rate decreased significantly in the vibrating abdomen group and the drug group(P<0.05).There were no significant differences between the vibrating abdomen group and the drug group(P>0.05). Conclusion:Vibrating the abdomen increases the food intake and body mass of anorexia model rats,reduces the residue of gastric contents,improves the small intestine propulsion rate,and therefore has a good therapeutic effect on anorexia.The mechanism may be related to inhibiting the secretion of CCK-8 and NT in plasma and promoting the release of MTL and GAS in serum.

Objective:To evaluate the effect of ultrasound-guided adductor canal block with bupivacaine liposome on analgesia in elderly patients undergoing total knee arthroplasty.Methods:This was a prospective study. Sixty American Society of Anesthesiologists Physical Status classification Ⅱ or Ⅲ patients, regardless of gender, aged 65-83 yr, weighing 50-80 kg, scheduled for elective unilateral total knee arthroplasty under subarachnoid anesthesia from April 2023 to January 2024 in Zhengzhou Orthopaedic Hospital, were divided into 2 groups ( n=30 each) using a random number table method: bupivacaine liposome group (LB group) and ropivacaine group (R group). Ultrasound-guided adductor canal block was performed at 30 min before subarachnoid anesthesia, bupivacaine liposome diluent 20 ml (133 mg) was injected in LB group, and 0.5% ropivacaine 20 ml was injected in R group. Patient-controlled intravenous analgesia was performed after operation, and tramadol was used for rescue analgesia when the visual analogue scale (VAS) score ≥3. VAS scores at rest and during activity were recorded at 8, 12, 24, 48 and 72 h after surgery. The time to the first pressing analgesia pump and rescue analgesia were recorded within 72 h after surgery. The quadriceps muscle strength was measured at 1 day before surgery and 12, 24, 48 and 72 h after surgery. The knee joint range of motion was assessed at 1 day before surgery and 24, 48 and 72 h after surgery. Patient′s satisfaction with analgesia was recorded at 72 h after surgery. The adverse reactions within 72 h after surgery were also recorded. Results:Compared with R group, VAS scores at rest and during activity were significantly decreased at 12, 24, 48 and 72 h after surgery, the time to the first pressing analgesia pump was prolonged, the rate of rescue analgesia after surgery was decreased, the score for the patient′s satisfaction with analgesia was increased, the knee joint range of motion was increased ( P<0.05), and no significant change was found in the quadriceps muscle strength and incidence of adverse reactions in LB group ( P>0.05). Conclusions:Ultrasound-guided adductor canal block with bupivacaine liposome provides better analgesia than ropivacaine in elderly patients undergoing total knee arthroplasty.

Objective:To evaluate the effect of pancreatic duct stenting in the treatment of severe acute pancreatitis (SAP).Methods:The clinical data of 68 patients with SAP admitted to the Department of Hepatobiliary Surgery, General Hospital of Ningxia Medical University from January, 2019 to July, 2020 were retrospectively analyzed, including 38 males and 30 females, aged (44.85±8.51) years old. The patients were divided into two groups according to the treatment modality: the conservative group ( n=41) which received the conservative management, and the stent group ( n=27) which underwent pancreatic duct stent implantation and conservative management. The basic information, parenteral nutrition support time, fasting days, and other clinical data of patients were collected. Serum amylase, white blood cell count, acute physiology and chronic health (APACHE) II score and CT score were compared between the two groups at admission and 48 hours after treatment. Results:The serum amylase, white blood cell count, APACHE II score and CT score of the two groups were significantly lower after treatment (all P<0.05). Compared with the conservative group, the APACHE II score [(5.52±2.15) vs. (8.76±2.50)] and CT score [(4.85±1.96) vs. (6.18±1.07)] of patients were lower in the stent group after treatment (both P<0.05). Pancreatic duct stents were successfully implanted in all 27 patients of the stent group. Intubation to the main pancreatic duct failed in one patient, while the accessory pancreatic duct was alternatively intubated through the accessory nipple. No severe complications such as iatrogenic pancreatitis, bleeding, and perforation occurred after endoscopic retrograde cholangiopancreatography. The incidence of postoperative local complications was lower [18.52%(5/27) vs. 41.46%(17/41)], the proportion of antibiotic use>3 types [29.63%(8/27) vs. 56.10%(23/41)] decreased, and the analgesic episodes decreased [2(1, 3) vs. 4(3, 6)] in the stent group. The antibiotic usage duration [8(3, 11) d vs. 13(10, 19) d], the parenteral nutrition time [7(4, 15)d vs. 15(8, 18)d], the fasting time [5(3, 11) d vs. 11(6, 13)d] and the hospital stay [10(5, 16) d vs. 15(13, 23)d] were all shortened (all P<0.05). Conclusion:Both conservative management and pancreatic duct stenting can alleviate the clinical symptoms of SAP, and pancreatic duct stenting could help reduce local complications, relieve symptoms, and shorten hospital stay.

Objective:To investigate the characteristics and clinical significance of distribution of bacteria and fungi in pancreatic fluid and bile in patients with acute biliary pancreatitis (ABP).Methods:The clinical data of patients with ABP who underwent endoscopic retrograde cholangiopancreatography (ERCP) and pancreatic duct stenting with simultaneous bacterial and fungal culture of bile and pancreatic fluid at the Department of Hepatobiliary Surgery, General Hospital of Ningxia Medical University from January 1, 2019, to June 30, 2021 were retrospectively analyzed. Of 202 patients, there were 102 males, and 100 females, aged (54±16) years old. Patients were divided into two groups by presence or absence of pancreatic infection: the pancreatic infection group ( n=20) and the non-pancreatic infection group ( n=182). Of the 76 patients with positive bile bacterial cultures, 60 patients with positive pancreatic fluid bacterial cultures were included in the positive pancreatic fluid culture group and 16 patients with negative pancreatic fluid cultures were included in the negative pancreatic fluid culture group. The clinical data including the type and distribution of bacteria cultured, complications, and co-infections of patients were compared. Factors associated with pancreatic infection were analyzed using logistic regression and the value of assessment of the associated factors was analyzed by plotting the receiver operating characteristic (ROC) curve. Results:Of 404 specimens (202 each of pancreatic fluid and bile) were sent for examination, 152 (37.6%) were positive. 174 strains were isolated from the 152 positive specimens, 96 (55.2%) gram-negative, 70 (40.2%) gram-positive and 8 (4.6%) fungal strains. Compared to the pancreatic fluid culture-negative group, patients in the pancreatic fluid culture positive group had a statistically significant ( P<0.05) increased risk of neutrophil to lymphocyte ratio, duration of fever, Balthazar CT score, complication rate, and development of pancreatic necrosis, pancreatic infection and systemic inflammatory response syndrome (SIRS). Compared to patients in the non-pancreatic infection group, patients in the pancreatic infection group had a statistically significant ( P<0.05) increase in duration of fever on admission, duration of fasting, and proportion of patients with combined SIRS, positive bile cultures, positive pancreatic fluid cultures, and diabetes mellitus. Logistic regression analysis showed that positive pancreatic fluid cultures ( OR=6.699, 95% CI: 1.159-38.725) and diabetes mellitus on admission ( OR=4.625, 95% CI: 1.304-16.394) were risk factors for late pancreatic infection ( P<0.05). The area under the ROC curve for the combination of both positive pancreatic fluid culture and diabetes mellitus in predicting late pancreatic infection in patients was 0.788, with a specificity of 59.30% and a sensitivity of 90.00%. Conclusions:Bacterial culture in pancreatic juice and bile of ABP patients showed mainly Gram-negative bacteria. Early culture of pancreatic juice and bile had positive significance in ABP evaluation, infection prediction and anti-infection treatment.

Objective: To observe the clinical efficacy of Tuina (Chinese therapeutic massage) plus oxiracetam in treating mild vascular dementia (VD) and seek its underlying mechanism. Methods: Ninety-six patients with mild VD were randomized into an observation group and a control group, with 47 cases in the observation group and 49 cases in the control group. The control group received oral oxiracetam capsules for treatment, and the observation group was given additional Tuina treatment. Before and after treatment, the mini-mental state examination (MMSE) was adopted to assess the patient's cognitive function; the activities of daily living (ADL) scale was used to evaluate their ability to conduct daily activities; changes in the serum inflammatory factors and oxidative stress indicators were also detected. Results: After treatment, the serum content of malondialdehyde (MDA) decreased in both groups (P<0.05) and was lower in the observation group than in the control group (P<0.05); the serum contents of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) increased in both groups (P<0.05) and were higher in the observation group than in the control group (P<0.05); the serum contents of interleukin (IL)-1, tumor necrosis factor (TNF)-α, IL-6, and IL-8 declined in both groups (P<0.05) and were lower in the observation group than in the control group (P<0.05). After the intervention, the levels of systolic velocity (Vs) and mean velocity (Vm) of the middle cerebral artery elevated, and the pulsatility index (PI) dropped in patients in the two groups, showing significant intra-group differences (P<0.05); the levels of Vs and Vm in the observation group were higher than those in the control group, and the PI was lower in the observation group than in the control group, showing significant between-group differences (P<0.05). The MMSE and ADL scores increased in both groups after the intervention (P<0.05) and were higher in the observation group than in the control group (P<0.05). Conclusion: In the treatment of mild VD, Tuina plus oxiracetam can improve the cerebral blood supply, ADL, and cognitive function; the mechanism may be associated with the reduction of oxidative stress damages and inflammatory reactions.

Objective To analyze the distribution status and agglomeration degree of radiological diagnosis and treatment resources in Beijing, and provide references for rationally coordinating the allocation of radiological diagnosis and treatment resources, formulating resource allocation policies, and promoting the stable development and efficient use of radiological diagnosis and treatment resources. Methods Based on the medical radiation protection monitoring data of Beijing medical and health institutions from 2019 to 2020, the current situation of radiological diagnosis and treatment resources is described by the number of radiological diagnosis and treatment resources, the average service volume, and the resource composition, and the distribution of radiological diagnosis and treatment resources in Beijing is evaluated with the aid of the agglomeration degree. Results The number of radiological diagnostic equipment, the number of service personnel, and the number of radiological workers engaged in third-level hospitals is the largest; for the number of service personnel for each type of single equipment, third-level hospitals account for a larger proportion, and radiotherapy and nuclear medicine services are concentrated in third-level hospitals. Human resource pressure and equipment service pressure are relatively high in third-level hospitals. First-level hospitals mainly undertake radiological diagnosis services. There is little difference in the amount of radiological diagnosis services per capita between second-level hospitals and third-level hospitals. Nuclear medicine and radiotherapy in third-level hospitals per capita service volume is significantly higher than that insecond-level hospitals. Radiological diagnosis and radiotherapy resources are concentrated in urban areas to a large extent. Conclusion There are obvious differences in the utilization of radiological diagnosis and treatment resources in different levels of hospitals. There is a significant concentration of radiological diagnosis and treatment resources in various districts. There is a certain degree of unbalanced distribution and inadequate utilization of radiological diagnosis and treatment resources in Beijing.

Objective:To monitor and analyze the activity concentrations of 7Be and 210Pb in atmospheric aerosol in Beijing from 2017 to 2020. Methods:Totally 1 074 atmospheric aerosol samples were collected by high flow air sampler (SnowWhite) including 275 in spring, 266 in summer, 262 in autumn and 271 in winter and subjected to analysis by low background high-purity germanium gamma-ray spectrometery (ORTEC) to determine the activity concentrations of 7Be and 210Pb. Results:The activity concentrations of 7Be in atmospheric aerosol were from 0.56 to 14.84 mBq/m 3, with an avearage of 6.84 mBq/m 3, and from 0.01 to 9.37 mBq/m 3 for 210Pb, with an avearage 3.19 mBq/m 3. The differences in activity concentrations of 7Be and 210Pb in atmospheric aerosol among differernt seasons were statistically significant ( F=32.66, 93.93, P<0.05). Activity concentration of 7Be was highest in spring, followed by autumn, and lowest in summer and winter. Activity concentration of 210Pb ranged from winter, autumn, spring to summer in descending order. Conclusions:The activity concentrations of 7Be and 210Pb in atmospheric aerosol in Beijing from 2017 to 2020 fluctated within the range of normal level.

Objective To evaluate the effect of oxycodone on function of GABAA receptors in dor-sal root ganglion ( DRG ) neurons of rats with neuropathic pain ( NP ) . Methods Thirty-six adult male Sprague-Dawley rats, weighing 180-220 g, aged 10 weeks, were allocated into 3 groups ( n=12 each) u-sing a random number table method: sham operation group ( group S ) , group NP and oxycodone group ( group O) . The sciatic nerve was only isolated but not ligated in group S. NP was induced by chronic con-striction injury. The sciatic nerve was exposed and 4 loose ligatures were placed on the sciatic nerve at 1 mm intervals with 4-0 chromic catgut. Oxycodone 15μg∕kg was intraperitoneally injected once a day for 14 con-secutive days from ligating the sciatic nerve to satisfaction in group O. The thermal paw withdrawal latency( TWL) was measured at 1 day before establishing the model ( T0 ) and 3, 5, 7, 10 and 14 days after es-tablishing the model ( T1-5 ) . The rats were sacrificed after measurement of pain threshold at T5 , and DRG neurons were acutely isolated for recording the amplitude of GABAA receptors-activated currents using whole-cell patch-clamp technique. Results Compared with group S, the TWL was significantly shortened at T1-5, and the amplitude of GABAA receptors-activated currents in DRG neurons was decreased in NP and O groups (P<0. 05). Compared with group NP, the TWL was significantly prolonged at T1-5, and the ampli-tude of GABAA receptors-activated currents in DRG neurons was increased in group O ( P<0. 05) . Conclu-sion Oxycodone can enhance the function of GABAA receptors-activated currents in DRG neurons and thus enhance GABAA receptors-mediated presynaptic inhibition, which may be related to the mechanism of oxyc-odone-induced reduction of NP in rats.