ABSTRACT
@#<b>Objective</b> To study whether the disinfection methods for thermoluminescence dosimeters used by major hospitals during the COVID-19 pandemic had an impact on monitoring personal dose of external irradiation, and to screen for the disinfection procedures suitable for use during the pandemic. <b>Methods</b> Hospitals with fever clinics during the epidemic in Shandong Province were selected from March to October 2020, we investigated the disinfection methods as well as the types and frequency of use of disinfection supplies used for thermoluminescence dosimeters during the pandemic in hospitals. Simulations were performed in experimental and control groups. <b>Results</b> The average doses measured by the disc dosimeter with different disinfection methods and the control group were 0.92-0.99 mSv and 0.98 mSv, respectively, and the deviation was ≤ 6%. The average doses measured by the glass tube dosimeter with different disinfection methods and the control group were 0.20-0.22 and 0.21, respectively, and the deviation was ≤ 5%. <b>Conclusion</b> The results showed that the commonly used disinfection methods had no influence on personal dose monitoring, but some disinfection measures were not suitable for dosimeters.
ABSTRACT
Objective To investigate the dose of radiation in children under going X-ray-guided air enema reduction, and to provide a basis for reducing the risk of radiation injury in pediatric patients. Methods Data were collected from children with intussusception who were treated with air enema. The experimental conditions of high, medium, and low doses of three age groups were analyzed. Phantoms were used to simulate the operation, and the radiation dose was measured using a thermoluminescence system. Results In children with intussusception, the success rate of air enema under the guidance of X-ray was 88% (including secondary intussusception), with anearly re-intussusception rate of 8%. The effective dose of treatment ranged from 0.57 to 12.33 mSv, and the tissues and organs with high absorbed dose were mainly in the chest and abdomen. Conclusion Children in different groups are exposed to significantly differentand relatively high doses. The operators are recommended to use ultrasonic guidance. With X-ray guidance, the exposure time should be minimized and protective equipment for children should be used.
ABSTRACT
Objective:To understand the 131I activity in thyroid of therapy workers in nuclear medicine department, and estimate the annual committed effective dose, in order to analyze the internal exposure of them. Methods:Six hospitals were investigated and 131I activity of thyroid was measured. The detection rate and activity value of thyroid 131I activity of therapy workers in nuclear medicine department were obtained from the six hospitals, and then the intake and annual committed effective dose were calculated. Results:A total of 63 iodine therapy workers from six hospitals were measured and 131I was detected for 52 workers among them, with the detection rate of 83% and 131I activities mostly lower than 200 Bq. The estimated annual committed effective dose ranged from 0.23 to 7.78 mSv. The annual committed effective dose to 84.6% of the workers was less than 2 mSv. Conclusions:Iodine therapy workers in nuclear medicine department should receive routine internal exposure personal monitoring, and the radiation protection system in all hospitals needs to be further improved.
ABSTRACT
@#<b>Objective</b> To explore the effect of coronavirus disease 2019 (COVID-19) on the frequency of chest CT scan. <b>Methods</b> A retrospective study was conducted to extract information on the number of outpatient, emergency, and inpatient visits and patients who had chest CT imaging examination from January 1 to December 31, 2020 and in the same period in 2019 through the hospital’s medical data platform for analysis, and the chi-square test was used to analyze whether the difference in the proportion of patients who had chest CT imaging examination between 2019 and 2020 was statistically significant. <b>Results</b> The proportion of outpatients and emergency patients with chest CT examination was significantly higher in 2020 than in 2019 (2.48% <i>vs</i> 1.47%, <i>χ</i><sup>2</sup> = 581.7, <i>P</i> < 0.000). The proportion of inpatients who underwent chest CT examination was significantly higher in 2020 than in 2019 (35.47% <i>vs</i> 28.01%, <i>χ</i><sup>2</sup> = 182.0, <i>P</i> < 0.000). <b>Conclusion</b> Under the COVID-19 epidemic, the proportion of chest CT examination in this hospital in 2020 shows a significant upward trend compared with the same period in 2019, which will increase the collective dose due to medical exposure, and the hospital should pay attention to the determination of the legitimacy of chest CT scan.
ABSTRACT
Objective By measuring the induced radioactivity of the medical electron linear accelerator, and analyzing the measuring results and the measuring process, the cooling law of the induced radioactivity was studied, to provide basic data for evaluating additional doses to patients, medical staff and the public. Methods Five Medical Electron Linear accelerators were used to measure the induced radioactivity by using automes-6150AD6/H+6150AD-b/H x-γ radiation peripheral dose equivalent rate meter for environmental monitoring. Results The level of induced radioactivity of 5 medical electron linear accelerators is related to the factors such as measuring position and time: 10 second after the end of beam output, the maximum dose equivalent rate is 5.55 μSv/h around 5 cm on the surface of the head housing of the accelerator, and the maximum ambient dose equivalent rate at 1 m from the fixed point of the housing is 4.07 μSv/h, 5 minutes after the end of output, the maximum dose equivalent rate is 2.11 μSv/h around the 5 cm surface and 1.77 μSv/h around the 1 m fixed point. Conclusion The measured radioactivity induced by the medical electron linear accelerator gradually cools over time, the measurement valuesare maintained in a relatively fixed range, and the fluctuation range of the values is narrow.
ABSTRACT
Traumatic brain injury (TBI), a growing public health problem, is a leading cause of death and disability worldwide, although its prevention measures and clinical cares are substantially improved. Increasing evidence shows that TBI may increase the risk of mood disorders and neurodegenerative diseases, including Alzheimer's disease (AD). However, the complex relationship between TBI and AD remains elusive. Metabolic dysfunction has been the common pathology in both TBI and AD. On the one hand, TBI perturbs the glucose metabolism of the brain, and causes energy crisis and subsequent hyperglycolysis. On the other hand, glucose deprivation promotes amyloidogenesis via β-site APP cleaving enzyme-1 dependent mechanism, and triggers tau pathology and synaptic function. Recent findings suggest that TBI might facilitate Alzheimer's pathogenesis by altering metabolism, which provides clues to metabolic link between TBI and AD. In this review, we will explore how TBI-induced metabolic changes contribute to the development of AD.
ABSTRACT
Objective:To understand the activity concentration of 131I aerosol in the air of the iodine treatment workplace and estimate the internal dose of 131I inhaled by medical staff in nuclear medicine. Methods:Using CF-1001BRL portable large capacity air sampler, the 131I aerosol in the iodine treatment workplace of nuclear medicine department of 6 hospitals in Shandong province was collected by iodine box, and the HPGe-γ energy spectrometer was used to measure the samples. The 131I activity concentration in iodine treatment workplace at 6 hospitals was obtained, and the internal dose to medical staff was estimated. Results:The 131I activity concentration in the air in iodine treatment workplaces at 6 hospitals ranged from 3.64 to 2.94×10 3 Bq/m 3. The 131I activity concentration in the controlled area (ward, patient passageway, subpacking room, operation administration room) was significantly higher than that in the supervised area. The highest 131I activity concentration, 2.62×10 2 Bq/m 3, in the supervised area was found in the medical care passageway. The estimated effective dose to nuclear medicine workers was 0.07-5.68 mSv, not exceeding the national limit. Conclusions:The phenomenon of 131I aerosol contamination still exists in the iodine treatment workplaces of nuclear medicine departments in hospitals, so it is necessary to carry out internal radiation monitoring for nuclear medicine departments all around the country, and explore more reasonable protection standards and methods.
ABSTRACT
Objective@#To estimate the doses to patients from ERCP operation through experimental measurements.@*Methods@#A retrospective analysis was made of 56 ERCP operations in three hospitals, and meanwhile, the tube voltage and current, fluoroscopy time, accumulated doses, DAPs (dose-area product) and photographic frames were also recorded for statistical analysis. Three cases of RECP operation that had led to high, medium and low DAP values were selected, respectively, as high, medium and low dose groups based on anthropomorphic phatom (AP). ERCP operation was simulated on AP on the basis of putting TLDs in it. The absorbed doses of organs were measured while effective doses while calculated.@*Results@#The effective doses for high, medium and low groups were 2.69, 11.52 and 39.27 mSv, respectively. The effective dose was 14 times higher in high dose group than that in low group. The highest organ doses for three groups were all concentrated in the irradiation fields.@*Conclusions@#Organ doses from ERCP phantom experiments vary largely in different groups. Compared with phantom experiments of other interventional types, ERCP can be regarded as one of interventional means leading to high-dose. It is advisable to reasonably and safely use intervention diagnosis and therapy and in order optimize radiation doses to patients.
ABSTRACT
Objective To estimate the doses to patients from ERCP operation through experimental measurements.Methods A retrospective analysis was made of 56 ERCP operations in three hospitals,and meanwhile,the tube voltage and current,fluoroscopy time,accumulated doses,DAPs (dose-area product) and photographic frames were also recorded for statistical analysis.Three cases of RECP operation that had led to high,medium and low DAP values were selected,respectively,as high,medium and low dose groups based on anthropomorphic phatom (AP).ERCP operation was simulated on AP on the basis of putting TLDs in it.The absorbed doses of organs were measured while effective doses while calculated.Results The effective doses for high,medium and low groups were 2.69,11.52 and 39.27 mSv,respectively.The effective dose was 14 times higher in high dose group than that in low group.The highest organ doses for three groups were all concentrated in the irradiation fields.Conclusions Organ doses from ERCP phantom experiments vary largely in different groups.Compared with phantom experiments of other interventional types,ERCP can be regarded as one of interventional means leading to high-dose.It is advisable to reasonably and safely use intervention diagnosis and therapy and in order optimize radiation doses to patients.
ABSTRACT
Objective To analyze the distribution characteristics and influencing factors of X-ray diagnostic imaging in Shandong province,and to estimate the application frequency of X-ray diagnostic imaging in the province,and provide data support for X-ray equipment.Methods A random sampliug method was used to extract 32 medical institutions as respondents from 10 prefecture-level cities in Shandong province.The basic information of medical institutions and the age,sex,examination and procedure of the subjects were analyzed.The distribution of the X-ray application was analyzed and estimated by using a multiple linear regression model.Results Totally 14 694 085 subjects were surveyed,and the proportion of male and female in the sample was not completely uniform.A total of 2 099 155 X-ray diagnostic information was collected in 2016,and the frequency of conventional radiography was the highest,accounting for 59.49％.The next was CT examination,accounting for 28.34％.The frequency of the two examinations showed an increasing trend with the age of subjects.For the total frequency of conventional diagnostic radiography and CT examination,the tertiary hospitals accounted for the highest proportion of the total,up to 52.13％,while the secondary hospitals accounted for the relatively low proportion of 30.09％,and the primary hospitals the lowest with 17.77％.The chest radiography had the highest proportion in conventional radiography accounting for 32.79％ of the total frequency of X-ray diagnostic imaging,and the head procedure had the highest proportion in CT examination,accounting for 10.07％ of the total frequency of X-ray diagnostic imaging.The fluoroscopy,mammography and dental radiography were mainly concentrated in the tertiary hospitals,and the primary hospitals had mainly radiography.Multiple linear regression models showed that the frequency of application of conventional X-ray diagnostic imaging (including radiography,fluoroscopy,dental radiography and mammography) was positively correlated with equipment quantity,number of outpatient and emergency patients,and tertiary hospitals (t=4.334,3.615,2.339,P＜ 0.05).CT examination was positively correlated with equipment quantity and the number of inpatient (t =2.167,2.595,P＜0.05).The frequency of conventional X-ray diagnostic imaging and CT examination in Shandong province were estimated about 491.17 examinations per 1 000 population and 258.17 examinations per 1 000 population respectively.Conclusions The frequency of X-ray exposure in Shandong province increased significantly compared with that during the " 9th Five-Year Plan" period.All relevant departments should take effective measures to strengthen medical radiation protection and reduce radiation risk.
ABSTRACT
The relevant literature of pathogenesis of essential hypertension (EH) and the clinical efficacy of acupuncture treatment of EH was retrieved from January 1, 1999 to February 28, 2018 in the CNKI and PubMed databases, and aimed to summarize and explore the mechanism of antihypertensive by acupuncture.It has been found that acupuncture exerts antihypertensive effect by coordinating multi-system, multi-target, multi-layer adjustment mechanism, such as acupuncture inhibiting of central and peripheral sympathetic nerve activity, rejusting immune system and expression of inflammatory response factors, regulating the balance of renin-angiotensin-aldosterone system (RAAS), improving vascular structure and function, the anti-oxidative stress and promoting autophagy.
Subject(s)
Humans , Acupuncture Therapy , Antihypertensive Agents , Essential Hypertension , Therapeutics , Oxidative Stress , Renin-Angiotensin SystemABSTRACT
The aim of present study was to explore the effect of triptolide derivative LB-1 on imiquimod (IMQ) induced psoriasiform inflammation in BALB/c mice, and to investigate the immune mechanism of LB-1 in the prevention and treatment of psoriasis. In the present study, topical application of IMQ for seven days induced the psoriasiform inflammation in BALB/c mice. This is a promising mouse model of psoriasis for the natural immune reaction compared to those induced by xenograft, trangenic or gene knockout. psoriasis area and severity index (PASI) score, hematoxylin-eosin (HE) staining and flowcytometry were employed to investigate the changes of psoriasiform inflammation, histopathological response and percentage of T cells, respectively. The result showed that LB-1 significantly attenuated the psoriasiform inflammation. Com-pared with model group, PASI score were decreased in the LB-1 group. In the isolated immunocytes of spleen, LB-1 decreased percentage of CD8+ (P +/CD8+ T cells at the dosage of 2 mg·kg-1 (P + T cells and CD3+ T cells at the dosage of 4 mg·kg-1. In conclusion, the present study demonstrated that LB-1 attenuated psoriasiform inflammation induced by imiquimod in BALB/c mice. The mechanism of LB-1 action may be related to change percentage of CD4+ T, CD8+ T cells in the spleen. These results provide a basis for LB-1 or other triptolide derivative in the intervention of psoriasis in the future.
ABSTRACT
With references of historical materials and modern literature regarding acupoint characteristic, a secondary analysis on the concept, origin, related factors and research methods in present research of acupoint characteristic is performed. The acupoint characteristic should be considered as an acupoint inherent attribute that could explain physiological and pathological manifestations at the same time, including location attribute and function attribute, which is related with time and treatment method. Some re-thinking on acupoint characteristic is proposed as well as advice on further research method and direction, hoping to promote the research development of acupoint characteristic.
Subject(s)
Humans , Acupuncture Points , Acupuncture Therapy , History , China , History, Ancient , Medicine in Literature , MeridiansABSTRACT
The purpose of this study is to investigate the activity and mechanism of a new anti-tumor agent T03. MTT and colony formation assay were performed to determine anti-proliferation activity of T03 in vitro. Antitumor activity was observed by Renca xenograft model in vivo. The effect of T03 on cell cycle and apoptosis were measured by FCM analysis. Western blotting was performed to investigate the expression level of proteins in HepG2 cell lines treated with T03. T03 had anti-tumor activity by inhibiting tumor cell growth and colony formation in vitro, especially on hepatocellular carcinoma cells (HCC). At the concentration of 10 micromol x L(-1), T03 induced cell apoptosis and cell cycle arrest in HCC. Moreover, it proved that T03 reduced the tumor weight with the rate of 42.30% without any obviously side effect in Renca xenograft model. At the concentration of 2.0 micromol x L(-1), T03 was able to reduce the level of p-c-Raf (Ser259), and thus blocked Raf/MEK/ERK and AKT signaling in HepG2 cell lines. The result suggested that T03 has the potential to inhibit cell proliferation and induce cell apoptosis both in vitro and in vivo, particularly active against HCC, indicating T03 and its analogues may serve as a new anti-cancer drug against hepatocellular carcinoma.
ABSTRACT
Hypoxia is a general characteristic of most solid malignancies and intimately related to cancer progression. Homeostatic response to hypoxia is primarily mediated by hypoxia inducible factor-1alpha (HIF-1alpha) that elicits transcriptional activity through recruitment P300 coactivator. Targeting the interaction of HIF- alpha and P300 would thus constitute a novel approach for cancer treatment by suppressing tumor angiogenesis and metastasis. Here, a screening assay was developed for inhibitors targeting the interaction between HIF-1alpha and P300. The nucleotide sequence of human HIF-1alpha and P300 were cloned into pBIND and pACT vectors, named pBIND-HIF1alpha and pACT-P300. The interaction of HIF-1alpha and P300 was identified in HEK293 cell using mammalian two-hybrid system. And compound chetomin decreased their interaction in this mammalian two-hybrid system. We further verified HIF-1 inhibition effect of chetomin in U251-HRE cells. Therefore, we established a screening assay combined HIF-1alpha and P300 mammalian two-hybrid system and U251-HRE reporter assay for HIF-1 selective inhibitors.
ABSTRACT
Hypoxia occurs in chronic and acute vascular diseases and tumor formation. The ability of tumor cells to maintain a balance between an adaptation to hypoxia and cell death is regulated by a family of transcription factors called hypoxia-inducible factor 1 (HIF-1). Tumor hypoxia mediated by HIF-1 would facilitate the likelihood of resistance to chemotherapy and radiotherapy, proliferation, metastasis and the invasive potential; all of which culminate in a decrease in patient survival. And HIF-1 alpha subunit decides the activity of HIF-1, which is regulated by oxygen. So understanding the role of HIF in signal pathway, drug resistance mechanism and its feature is crucial for developing novel anticancer therapies. In recent years, more attentions have focused on HIF-1 alpha inhibitors. It is expected that development of more potent and selective HIF inhibitors will provide an effective treatment of cancer and other HIF-related diseases. So we will focus on the biological characteristics and mechanism of HIF-1 to review currently studied HIF-1 inhibitors.
ABSTRACT
Hypoxia-inducible factor-1 (HIF-1) is a key transcription factor on hypoxia responses in mammalian tissues. HIF-1 plays as a positive factor in solid tumor and leads to hypoxia-driven responses that enhance its downstream gene expression for tumor growth and survival. LXY6099 was obtained by the structural modification and optimization of manassantin A (MA) as a high potent HIF-1 inhibitor. Antitumor activity of LXY6099 was observed in this study. LXY6099 with an IC50 value of 2.46 x 10(-10) mol x L(-1) showed more sensitive inhibition activity to HIF-1 than that of MA detected by reporter gene assay (> 100 folds). It showed strong inhibition on the growth of human solid tumor cell lines. Furthermore, LXY6099 exhibited significant antitumor activity against established human tumor xenografts in nu/nu mice with treatment of MX-1 breast cancer. Thus, LXY6099 as a novel HIF-1 inhibitor could be further developed into anti-cancer agents.
ABSTRACT
Hypoxia-inducible factor-1 (HIF-1) is a key transcription factor on hypoxia responses in mammalian tissues. HIF-1 plays as a positive factor in solid tumor and leads to hypoxia-driven responses that enhance its downstream gene expression for tumor growth and survival. LXY6099 was obtained by the structural modification and optimization of manassantin A (MA) as a high potent HIF-1 inhibitor. Antitumor activity of LXY6099 was observed in this study. LXY6099 with an IC50 value of 2.46 x 10(-10) mol x L(-1) showed more sensitive inhibition activity to HIF-1 than that of MA detected by reporter gene assay (> 100 folds). It showed strong inhibition on the growth of human solid tumor cell lines. Furthermore, LXY6099 exhibited significant antitumor activity against established human tumor xenografts in nu/nu mice with treatment of MX-1 breast cancer. Thus, LXY6099 as a novel HIF-1 inhibitor could be further developed into anti-cancer agents.
Subject(s)
Animals , Humans , Antineoplastic Agents , Pharmacology , Breast Neoplasms , Metabolism , Cell Line, Tumor , Gene Expression Regulation, Neoplastic , Heterografts , Hypoxia-Inducible Factor 1 , Metabolism , Lignans , Pharmacology , Mice, NudeABSTRACT
Hypoxia occurs in chronic and acute vascular diseases and tumor formation. The ability of tumor cells to maintain a balance between an adaptation to hypoxia and cell death is regulated by a family of transcription factors called hypoxia-inducible factor 1 (HIF-1). Tumor hypoxia mediated by HIF-1 would facilitate the likelihood of resistance to chemotherapy and radiotherapy, proliferation, metastasis and the invasive potential; all of which culminate in a decrease in patient survival. And HIF-1 alpha subunit decides the activity of HIF-1, which is regulated by oxygen. So understanding the role of HIF in signal pathway, drug resistance mechanism and its feature is crucial for developing novel anticancer therapies. In recent years, more attentions have focused on HIF-1 alpha inhibitors. It is expected that development of more potent and selective HIF inhibitors will provide an effective treatment of cancer and other HIF-related diseases. So we will focus on the biological characteristics and mechanism of HIF-1 to review currently studied HIF-1 inhibitors.
Subject(s)
Humans , Cell Death , Hypoxia-Inducible Factor 1 , Metabolism , Hypoxia-Inducible Factor 1, alpha Subunit , Metabolism , Neoplasms , Drug Therapy , Oxygen , Metabolism , Signal TransductionABSTRACT
Hypoxia is a general characteristic of most solid malignancies and intimately related to cancer progression. Homeostatic response to hypoxia is primarily mediated by hypoxia inducible factor-1alpha (HIF-1alpha) that elicits transcriptional activity through recruitment P300 coactivator. Targeting the interaction of HIF- alpha and P300 would thus constitute a novel approach for cancer treatment by suppressing tumor angiogenesis and metastasis. Here, a screening assay was developed for inhibitors targeting the interaction between HIF-1alpha and P300. The nucleotide sequence of human HIF-1alpha and P300 were cloned into pBIND and pACT vectors, named pBIND-HIF1alpha and pACT-P300. The interaction of HIF-1alpha and P300 was identified in HEK293 cell using mammalian two-hybrid system. And compound chetomin decreased their interaction in this mammalian two-hybrid system. We further verified HIF-1 inhibition effect of chetomin in U251-HRE cells. Therefore, we established a screening assay combined HIF-1alpha and P300 mammalian two-hybrid system and U251-HRE reporter assay for HIF-1 selective inhibitors.