Objective To evaluate the radiation dose levels induced by secondary neutrons at different locations inside proton therapy treatment rooms, and analyze the distribution characteristics of neutron energy spectra by combining experimental measurements with simulations, and to provide a theoretical basis and technical support for radiation protection design and management in proton therapy. Methods Multiple representative measurement points were established in the treatment rooms of two hospital-based proton therapy centers. The DIAMON neutron spectrometer was employed to perform in-situ measurements of secondary neutron doses and energy spectra. Three-dimensional simulation models of treatment rooms were constructed using the FLUKA code to simulate the generation and transport of secondary neutrons. Results Measurements showed that the neutron dose was highest near the target region, reaching up to 4293.750 µSv/h. The doses at the maze entrance were the next highest, ranging from 422.091 to 489.268 µSv/h, while the doses in the middle section of the maze ranged from 2.860 to 6.727 µSv/h. The neutron energy spectra exhibited a triple-peak pattern. Conclusion Significant accumulation of secondary neutrons was observed near the target and in the maze regions during proton therapy, with intermediate-energy neutrons being the dominant dose contributor. The consistency between measurements and simulations validated the reliability of the model, which can provide a basis for optimizing treatment room shielding and controlling occupational exposure for staff.

Objective:To establish a highly-sensitive method for the rapid measurement of 137Cs in seawater with an view to its preliminary application in eight coastal provinces of China. Methods:The method employed nickel potassium polyacrylonitrile (KNiFC-PAN), an organic polymer-based ion exchanged resin material, to filter and adsorb 137Cs from seawater at a rate of 60 ml/min via a peristaltic pump. The adsorption efficiency of KNiFC-PAN was determined by measuring the cesium ion concentration before and after adsorption in seawater, with the addition of stable cesium, using inductively coupled plasma mass spectrometry (ICP-MS). Three KNiFC-PAN matrix components of 137Cs standard samples were prepared for the efficiency calibration of well type high purity germanium gamma spectrometer to obtain its detection efficiency. Results:The established measuring method can complete the filtration and adsorption of 137Cs from 20 L seawater within 6-8 h, which was twice as fast as the co-precipitation method with phosphomolybdic acid-ammonium molybdate taking more than 12 h, as stipulated in the GB/T 16145-2022 standard. The cesium recovery rate was as high as 98.02%. The relative standard deviation of the efficiency calibration result for the three prepared standard samples was 1.30%, and the detection limit for 137Cs was 0.26 Bq/m 3. The activity concentrations of 137Cs in offcoast seawater in eight coastal provinces of China were detected ranging from 0.38 to 1.24 Bq/m 3. The activity concentration of 137Cs in coastal seawater of China was at the background level, while as reported in 2019 was 0.03-1.92 Bq/m 3 in the eastern Chinese seas and 1-2 Bq/m 3 in the Pacific Ocean. Conclusions:This method has high detection sensitivity and can quickly obtain the values of activity concentration of 137Cs in seawater, thus providing a rapid and feasible method for emergency monitoring of 137Cs in China.

Objective To observe CT and MRI manifestations of gastritis cystica profunda(GCP).Methods Seventeen patients with GCP confirmed by operation or biopsy pathology were enrolled,and lesions'CT and MRI manifestations were observed.Results Among 17 cases,16 cases(16/17,94.12％)were found with single lesion and 1(1/17,5.88％)with diffuse multiple lesions.The lesion located in the fundus of stomach in 5 cases(5/17,29.41％),in the body of stomach in 4 cases(4/17,23.53％),in the cardia and antrum of stomach each in 3 cases(3/17,17.65％)and in the pylorus in 1 case(1/17,5.88％),while 1 case(1/17,5.88％)was found with diffused multiple lesions within stomach.Non-enhance CT showed local thickening of gastric wall in 10 cases(10/17,58.82％),all were isodensities,and the mucosa uniformly enhanced in contrast enhance CT(CECT).Predominately cystic lesion in 5 cases(5/17,29.41％)presented as submucosal cystic protrusions,and grew into the stomach cavity with circular or oblong low density in non-enhanced CT,while sandwich enhancement of mucosa was observed in CECT.Among these 5 cases(5/17,29.41％),MRI showed lesion confined to the submucosa with low signal on T1WI and high signal on T2WI,while diffusion weighted imaging showed unrestricted diffusion,and the enhancement pattern was consistent with that of CT in 2 cases.In other 2 cases(2/17,11.77％)with cystic-solid lesion,non-enhanced CT showed soft tissue density,while CECT showed lump-like stratified enhancement.Conclusion CT and MRI manifestations of GCP had certain characteristics.

Objective:To investigate the clinical application effects of free transplantation of lobulated inguinal flaps.Methods:This study was a retrospective observational study. From July 2019 to April 2024, 34 patients with skin defect wounds whose wounds in one part met the inclusion criteria were admitted to Tongren Hospital of Wuhan University & Wuhan Third Hospital, including 28 males and 6 females, aged 26 to 59 years. The wound area in the recipient area ranged from 3.0 cm×2.0 cm to 25.0 cm×20.0 cm. The lobulated inguinal flap pedicled with the branch of the superficial circumflex iliac artery were obtained in 19 patients, and the lobulated inguinal flap pedicled with the main artery of the superficial circumflex iliac artery and the superficial inferior epigastric artery were obtained in 15 patients. The total area of the flaps ranged from 6.0 cm×2.2 cm to 27.0 cm×23.0 cm. The flaps were divided into 2 to 4 lobes, and the area of each lobe ranged from 2.0 cm×1.0 cm to 17.0 cm×12.0 cm. Each lobe of the flaps was reassembled, spliced, or directly transplanted onto the wounds, and the donor wounds were sutured in layers. The survival of each lobe of the flaps and wound healing in the recipient and donor areas were observed, and the wound recovery in the recipient and donor areas were followed up. At the last follow-up, the patient's satisfaction with the efficacy was assessed by 5-grade Likert scale.Results:A small amount of necrosis appeared in the tip of one lobe of the flaps in 4 patients after surgery, which healed after trimming. The flaps of the remaining 30 patients survived. The wounds in the recipient areas healed smoothly. There was a small amount of necrosis at the suture edge of the donor areas in 3 patients, which healed after local trimming and dressing change. The donor wounds healed well in the remaining 31 patients. During the follow-up of 6 to 42 months, all the recipient wounds were well repaired, and the shape of the donor areas was good. At the last follow-up, 15 patients were very satisfied with the efficacy, 15 were relatively satisfied, and 4 were generally satisfied.Conclusions:Through preoperative ultrasonic examination and positioning, the inguinal flap is designed according to the course of blood vessels and lobulated with the branch of the superficial circumflex iliac artery or the main artery of the superficial circumflex iliac artery and the superficial inferior epigastric artery as the pedicles. The anatomical process is reliable and the blood flow of the flap after being lobulated is rich, which can meet the repair needs of various skin defect wounds. The repair effect is good, and the damage in the donor area is small, which is worthy of promotion.

Objective To standardize and enhance the cleanliness of hospital floor and cleaning tools,significantly re-duce the influence of the predisposing factors that easily cause hospital-acquired infectious events,and reduce the possibility of such events due to inadequate cleaning and hygiene practices.Methods This study used Guangdong Second Provincial General Hospital as the research subject,cleaning tools were washed using both traditional manual disinfection and centralized mechanical cleaning and disinfection methods.Relevant experimental data were collected and compared to determine which method was more effective in terms of cleaning quality and optimal utilization of human resources.Results The bacterial colony count of floor tow-els treated with centralized mechanical cleaning and disinfection[(2.34±0.78)cfu/cm2]was significantly lower than that of the traditional manual cleaning group[(32.34±15.63)cfu/cm2].Similarly,the bacterial colony count on the floor cleaned with me-chanically centralized disinfected towels[(4.75±1.58)cfu/cm2]was much lower than that of the traditional manual disinfection group[(17.74±10.21)cfu/cm2)].Additionally,the bacterial colony count on door handles treated with centralized mechanical disinfection[(2.8±1.2)cfu/cm2]was significantly lower than that of the manual method[(10.1±5.7)cfu/cm2].Conclusion The centralized mechanical cleaning and disinfection method significantly mitigates the risk of hospital-acquired infections caused by insufficient disinfection of cleaning tools,while improving both the efficiency and quality of sanitation processes.

Objective To observe CT and MRI manifestations of gastritis cystica profunda(GCP).Methods Seventeen patients with GCP confirmed by operation or biopsy pathology were enrolled,and lesions'CT and MRI manifestations were observed.Results Among 17 cases,16 cases(16/17,94.12％)were found with single lesion and 1(1/17,5.88％)with diffuse multiple lesions.The lesion located in the fundus of stomach in 5 cases(5/17,29.41％),in the body of stomach in 4 cases(4/17,23.53％),in the cardia and antrum of stomach each in 3 cases(3/17,17.65％)and in the pylorus in 1 case(1/17,5.88％),while 1 case(1/17,5.88％)was found with diffused multiple lesions within stomach.Non-enhance CT showed local thickening of gastric wall in 10 cases(10/17,58.82％),all were isodensities,and the mucosa uniformly enhanced in contrast enhance CT(CECT).Predominately cystic lesion in 5 cases(5/17,29.41％)presented as submucosal cystic protrusions,and grew into the stomach cavity with circular or oblong low density in non-enhanced CT,while sandwich enhancement of mucosa was observed in CECT.Among these 5 cases(5/17,29.41％),MRI showed lesion confined to the submucosa with low signal on T1WI and high signal on T2WI,while diffusion weighted imaging showed unrestricted diffusion,and the enhancement pattern was consistent with that of CT in 2 cases.In other 2 cases(2/17,11.77％)with cystic-solid lesion,non-enhanced CT showed soft tissue density,while CECT showed lump-like stratified enhancement.Conclusion CT and MRI manifestations of GCP had certain characteristics.

OBJECTIVE: To investigate the clinical characteristics and genetic etiology of a male with a normal phenotype and SRY gene-positive 46,XX/46,XY tetrazoospermia chimerism. METHODS: A male patient with an abnormal peripheral blood chromosomal karyotype detected at the Infertility Center of Taizhou Hospital of Zhejiang Province on December 2, 2013 was selected as the study subject. Peripheral venous blood samples were collected from the proband and his family members, together with a semen sample from the proband. Chromosomal karyotype analysis, red blood cell blood group identification, chromosomal microarray analysis (CMA), fluorescence in situ hybridization (FISH), sex-determining region Y (SRY) gene detection, and short tandem repeat (STR) microsatellite marker analysis were performed on the peripheral venous blood sample from the proband. Routine semen analysis, sperm FISH, and STR testing were also conducted. STR verification was performed on both parents. This study was approved by the Medical Ethics Committee of the hospital (Ethics No.: k20201009). RESULTS: The proband, a 37-year-old male, had normal secondary sexual characteristics and external genitalia development. The chromosomal karyotype of his peripheral blood sample was 46,XX[94]/46,XY[6]. ABO blood group typing was positive for Rh(D) type O and negative for Rh(D) type A, indicating the presence of two red blood cell populations. CMA result was arr[GRCh37](1-22)×2,(XX)×1. Autosomal and X chromosome SNP genotypes were BB-BB, AB-AB, and AA-AA, making it impossible to identify homozygous/heterozygous chimerism. FISH detection of interphase nuclei showed nuc ish XX[92]/XY[8]. Testing of the SRY gene was positive. STR analysis showed a single X peak (no Y peak) at the AMEL locus, 10/12 at the Penta D locus, and no third allele at other loci. Routine semen analysis were normal. Sperm FISH detection showed haploid nuclei nuc ish X[53]/Y[47]. Sperm STR analysis revealed an X/Y bimodal distribution at the AMEL locus and a 9/14 distribution at the Penta D locus, with no third allele observed at other loci. Above results suggested that the proband's blood and germ cell lines had originated from a heterozygous chimera formed by the fusion of two different zygotes. CONCLUSION Combined genetic techniques confirmed that the proband's peripheral blood AMEL genotype is X/X, while the sperm is X/Y. The Penta D locus showed a bi-allelic heterozygous pattern of 10/12 in the peripheral blood sample and 9/14 in the sperm sample, suggesting that the proband is a tetrazygotic chimera resulted from the fusion of 46,XX/46,XY zygotes.
Humans ; Male ; Adult ; Chimerism ; Microsatellite Repeats ; Sex-Determining Region Y Protein/genetics* ; Phenotype ; Genes, sry ; In Situ Hybridization, Fluorescence ; Karyotyping

Postoperative infection of internal fixation of closed fractures the lower limbs in adults represents a devastating complication, characterized by diagnostic challenges, prolonged treatment duration and high disability rates. Current management of these infections faces multiple challenges, such as difficulties in early accurate diagnosis, and various controversies about the treatment plan, leading to poor overall diagnosis and treatment results. To address these issues, based on evidence-based medicine and principles with emphasis on scientific rigor, clinical applicability and innovation, the Trauma Branch of the Chinese Medical Association, Orthopedic Branch of the Chinese Medical Doctor Association, Orthopedics Branch of the Chinese Medical Association, and Trauma Orthopedics and Polytrauma Group of the Resuscitation and Emergency Committee of the Chinese Medical Doctor Association have collaboratively organized a panel of relevant experts to develop the Guideline for diagnosis and treatment of infection after internal fixation of closed lower limb fractures in adults ( version 2025). The guideline proposed 10 recommendations, aiming to provide a foundation for standardized diagnosis and treatment of postoperative infection in adults with closed lower limb fractures.

Objective:To establish a highly-sensitive method for the rapid measurement of 137Cs in seawater with an view to its preliminary application in eight coastal provinces of China. Methods:The method employed nickel potassium polyacrylonitrile (KNiFC-PAN), an organic polymer-based ion exchanged resin material, to filter and adsorb 137Cs from seawater at a rate of 60 ml/min via a peristaltic pump. The adsorption efficiency of KNiFC-PAN was determined by measuring the cesium ion concentration before and after adsorption in seawater, with the addition of stable cesium, using inductively coupled plasma mass spectrometry (ICP-MS). Three KNiFC-PAN matrix components of 137Cs standard samples were prepared for the efficiency calibration of well type high purity germanium gamma spectrometer to obtain its detection efficiency. Results:The established measuring method can complete the filtration and adsorption of 137Cs from 20 L seawater within 6-8 h, which was twice as fast as the co-precipitation method with phosphomolybdic acid-ammonium molybdate taking more than 12 h, as stipulated in the GB/T 16145-2022 standard. The cesium recovery rate was as high as 98.02%. The relative standard deviation of the efficiency calibration result for the three prepared standard samples was 1.30%, and the detection limit for 137Cs was 0.26 Bq/m 3. The activity concentrations of 137Cs in offcoast seawater in eight coastal provinces of China were detected ranging from 0.38 to 1.24 Bq/m 3. The activity concentration of 137Cs in coastal seawater of China was at the background level, while as reported in 2019 was 0.03-1.92 Bq/m 3 in the eastern Chinese seas and 1-2 Bq/m 3 in the Pacific Ocean. Conclusions:This method has high detection sensitivity and can quickly obtain the values of activity concentration of 137Cs in seawater, thus providing a rapid and feasible method for emergency monitoring of 137Cs in China.

With the widespread application of proton therapy in tumor radiation treatment, the health effects of secondary neutron radiation on patients and medical personnel have become a key concern in radiation protection. Currently, there is no commonly accepted technical standard for neutron dose measurement in proton therapy, making it difficult to compare neutron doses across studies and hindering the standardized development of radiation protection strategies. This paper provides a systematic review of commonly used neutron dose measurement methods and Monte Carlo simulation approaches. This article also explores the key challenges and potential improvements in neutron dose measurement in proton therapy.