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Objective:To analyze the differences between trans-radial access (TRA) and trans-femoral access (TFA) in hepatic arterial perfusion chemotherapy (HAIC) in terms of patient experience, postoperative complications, and patient preferences; explore whether TRA in HAIC is associated with better patient experience and compliance; and determine whether it is safer than TFA.Methods:The study was a retrospective cohort study of patients with advanced hepatocellular carcinoma and liver metastases from colorectal cancer treated with HAIC. We enrolled a total of 91 patients with advanced liver malignancies treated with HAIC from November 2022 to May 2023 in the Department of Interventional Therapy and Hepatobiliary Medicine at Tianjin Medical University Cancer Hospital. The patients were divided into three groups: group TRA ( n=20, receiving TRA HAIC only), group TFA ( n=33, receiving TFA HAIC only), and crossover group [ n=19, receiving TFA HAIC (Cross-TFA group) first, followed by TRA HAIC (Cross-TRA group)]. Meanwhile, to facilitate the expression of partial results, all patients receiving TRA HAIC were defined as the TRA-HAIC group ( n=39, TRA+Cross-TRA group), and all patients receiving TFA HAIC were defined as the TFA-HAIC group ( n=52, TFA+Cross-TFA group). The primary research index was the Quality of Life (QOL) visualization scale score. The secondary research index included approach-related and catheter-related adverse events, duration of surgery, and mean length of patient stay. We used various statistical methods such as Mann-Whitney U test, t-test, Chi-square test, Fisher′s exact test, univariate logistic regression analysis, and multi-factor analysis. Results:TRA patients had significantly lower QOL scores than TFA patients (all P<0.001). The QOL scores of the Cross-TRA group were significantly lower than those of the Cross-TFA group (pain at the puncture site Z=-3.24, P=0.001, others P<0.001). The QOL scores of the Cross-TRA group were compared with those of the TRA group, which showed that the scores of the Cross-TRA group in overall discomfort ( Z=-3.07, P=0.002), postoperative toilet difficulty ( Z=-2.12, P=0.034), and walking difficulty ( Z=-2.58, P=0.010) were significantly lower than those of the TRA group. Satisfaction scores were significantly higher in the Cross-TRA group than in the Cross-TFA group ( Z=-3.78, P<0.001), and patients were more likely to receive TRA HAIC as the next procedure ( χ2=30.42, P<0.001). In terms of mean length of stay, patients receiving TRA HAIC had a significantly lower mean length of stay than those receiving TFA HAIC (50.1±3.2 h vs. 58.4±6.4 h, t=7.98, P<0.001). The incidence of radial artery occlusion (RAO) as an approach-related adverse event was 15.4% (6/39) in the TRA-HAIC group, which was significantly higher than that in the TFA-HAIC group (15.4% vs. 0, χ2=8.56, P=0.005). Notably, multifactorial analysis of RAO-related factors showed that intraoperative enoxaparin use and patency of radial artery flow during pressure were significantly associated with a reduced risk of postoperative RAO ( P=0.037 for enoxaparin use and P=0.049 for pressure). Conclusions:With respect to procedure approach, TRA was significantly better than TFA in terms of patient satisfaction and mean length of stay. Through further process optimization and prevention of adverse reactions, the incidence of adverse reactions can be maintained at a relatively low level, so that patients can benefit from TRA in future operations in terms of cost-effectiveness and medical efficiency.
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Alpha1-acid glycoprotein (AGP), also known as oral mucus protein (ORM), is an acute phase positive protein. AGPs have various biological activities, such as drug transport, immune regulation, maintenance of capillary barrier, regulation of lipid metabolism, etc. AGP mainly exists in liver cells, but it is also expressed in other tissue cells, such as adipose tissue, brain tissue, endothelial cells and immune cells. This article mainly reviews the application of AGP in pulmonary diseases, and the role,significance and related new developments in different systemic diseases.
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Syringocystadenoma papilliferum (SCAP) and apocrine hidrocystoma (AH) are benign apocrine neoplasms that usually occur separately. SCAP arises predominantly in head and neck, while AH typically develop in periorbital area. We report a case of a 68-year-old male with an asymptomatic erythematous papulonodule that occurred on his back 3 years ago. Histologic examination showed cystic invagination extending from the epidermis into the dermis with some papillary projections. The invaginated portion was lined by epithelial bilayer composed of cuboidal and columnar cells, and decapitation secretion was observed in the inner epithelial layer. In the deep dermis, multiple cystic spaces with variable sizes were observed, and these cysts also presented double layers of the epithelium and decapitation secretion.According to such histologic features, the coexistence of SCAP and AH within a single lesion was demonstrated. The patient was recommended to completely remove the remaining lesion after punch biopsy, but he refused further surgical management. Herein, we report an unusual case of complex apocrine tumor with a rare composition in an atypical site.
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This study aimed to investigate the prevalence of depression among Koreans living in urban and rural areas, stratified by socioeconomic status. The study included 216,765 participants from the 2017 Korean Community Health Survey. Depressive symptoms were assessed using the PHQ-9, with a score of 10 or higher indicating depressive symptoms. Residences with the words Eup and Myeon in their addresses were categorized as rural areas, and residences with Dong in their addresses as urban areas. Socioeconomic status was evaluated by household income and education level. A Poisson regression analysis with sampling weights was conducted and adjusted for demographic, lifestyle, socioeconomic status, and comorbidity. The adjusted prevalence rate of depressive symptoms was 3.33% (95% CI, 3.21-3.45) in urban areas and 2.59% (95% CI, 2.43-2.74) in rural areas. The prevalence of depressive symptoms in urban areas was 1.29 times (95% CI, 1.20-1.38) higher than in rural areas. The prevalence rate ratio for depressive symptoms in urban areas compared to rural areas sorted by monthly incomes was 1.39 (95% CI, 1.28-1.51) for less than 2 million won, 1.22 (95% CI, 1.06-1.41) for 2 to 3.99 million won, and 1.09 (95% CI, 0.90-1.32) for more than 4 million won, and the urban-rural difference was more evident in lower household income subjects (p for interaction=0.033). However, urban-rural differences did not differ according to sex, age, or education level. In conclusion, we found urban-rural differences in depressive symptoms in a representative sample of Koreans, and revealed that these differences may vary according to income level. These results suggest that mental health policy must consider the health disparities according to residence and income.
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To give full play to the important role of courses for ideological and political education in moral cultivation, teaching group in the course of oral histology and pathology in Zhejiang University systematically studied the teaching model of which ideological and political education integrated into the course of oral histology and pathology, and put forward a quality evaluation index system of the course. This paper emphatically introduces the general framework of the course, as well as the experience and practices in the aspects of resource mining, teaching design, curriculum evaluation, etc. The quality of the course was evaluated by using the system, which showed that the grade of the course was AAA (excellent) and 95.5% (275/288) students agreed to integrate ideological and political content into the course. The teaching group believes that the integration of the ideological and political content in the course reflects the complementary effect of "teaching" and "educating", and the ideological and political quality as well as the professional level of the teachers are the primary factor to determine the quality of the course. This paper aims at providing a reliable reference for promoting the construction of courses for ideological and political education in the area of oral medical education.
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Objective To investigate the safety and efficacy of photodynamic therapy (PDT) for malignant obstruction of the biliary tract. Methods We retrospectively analyzed the clinical data of patients with malignant biliary obstruction treated by PDT in our medical center. On the basis of different treatment plans, the patients were categorized into the photodynamic only group and the combined treatment group, in which additional interventional operations, targeted therapy, or immunotherapy were arranged. The alterations in liver function, duration of biliary patency, and postoperative complications that occurred within one month were closely monitored in both groups. Results A total number of 19 patients were enrolled in this study. The technical success rate of PDT was 100%. The deterioration of liver function was not observed in any patients within one month after PDT. Within a maximum of 17.7 months follow-up, the patency rates of the biliary tract were 100.0%, 89.5%, 72%, and 64% at 1, 3, 6, and 12 months after the procedure, respectively. The mean biliary patency time was 6.9±0.8 months (95%CI: 5.2-8.7 months). Specifically, the biliary patency times for Bismuth type Ⅲ and Ⅳ were 7.5±1.1 and 6.1±1.3 months, respectively. The biliary patency time was around 3.3±0.7 months in the photodynamic only group and 7.9±0.9 months in the combined treatment group (P=0.017). Conclusion PDT for Bismuth Ⅲ-Ⅳ malignant biliary obstruction is safe and effective. Moreover, the period of biliary patency is greatly extended when PDT is combined with systemic therapy.
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Military vocational education has become one of the strategies to strengthen the military in the new era. The army urgently needs to build a number of featured online courses of military vocational education. Therefore, taking the course "Knowledge and Skills of Health Education for the Army" as an example, this paper discusses the overall construction objectives, construction ideas, teaching content, curriculum and test question bank construction of the course. In addition, this paper analyzes and summarizes the problems existing in the teaching organization, implementation, and preliminary application, so as to provide ideas and construction strategies for the construction of online open courses in other military vocational education.
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To investigate the effect of long-term indwelling gastric tube on the prevention and treatment of esophageal stenosis after endoscopic submucosal dissection (ESD) for esophageal circumferential superficial cancer, data of patients with esophageal circumferential superficial cancer who underwent ESD in the First Affiliated Hospital of Nanjing Medical University from January 2018 to December 2021 were retrospectively analyzed. There were 15 patients with gastric tube placement (GTP) after ESD (the GTP group ), and 23 patients without GTP (the non-GTP group). The general information, lesion location, pathological stage, postoperative complications, degree of esophageal stenosis (water intake), pain conditions, number of hospitalizations and medical expenses were compared between the two groups. The results showed that there was no significant difference in age, gender, lesion location or postoperative pathological stage between the two groups ( P>0.05). Compared with the non-GTP group, the rate of water intake in the GTP group was significantly higher (11/15 VS 6/23, P<0.05), the frequency of pain was less in the GTP group (7.3±3.1 times VS 10.7±3.6 times, t=3.00, P<0.05), and the number of hospitalizations and the medical expenses after ESD to before and after stent placement were significantly lower in the GTP group than those in the non-GTP group ( P<0.05). There were no significant differences in the incidence of delayed bleeding and perforation, or time of the first stenosis after ESD between the two groups ( P>0.05). The results of the study initially showed that long-term indwelling gastric tube after ESD can reduce the degree of esophageal stenosis with good safety for esophageal circumferential superficial lesions.
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In the past few years, there has seen an increase in the detection rate of early upper gastric cancer. Early upper gastric cancer is of good prognosis. How to further enhance the postoperative quality of life of patients has increasingly become an issue of concern. This has naturally given rise to function-preserving proximal gastrectomy. However, due to its damage to the original structure of cardia and its vicinity, proximal gastrectomy is prone to postoperative reflux. To prevent postoperative reflux, various ways of digestive tract reconstruction have emerged one after another, but the optimal way thereof remains controversial. Therefore, reducing postoperative reflux through an appropriate way of digestive tract reconstruction has been taken as a focus of proximal gastrectomy. Esophagogastric anastomosis with seromuscular flap technique, as a way of digestive tract reconstruction, builds an "artificial cardia" on the basis of guarantee of normal entry of food into the digestive tract, and functions against postoperative reflux. For its good anti-reflux effect, eso-phagogastric anastomosis with seromuscular flap technique has gradually become a research focus. On top of the latest research progress at home and abroad and relevant evidence-based medicine, the authors provide on the principles, key points, improvement, postoperative status, and applica-tion of esophagogastric anastomosis with seromuscular flap technique in laparoscopic proximal gastrectomy.
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The problems existing in the teaching mode of the traditional medical instrument practice course were introduced,and a medical instrument experimental training platform was constructed based on the maintenance demonstrators for monitor and ultrasound machine.Teaching reform was carried out with the developed training platform,and the teaching efficacy was analyzed deeply.References were provided for the improvement of the medical instrument practice course in the biomedical engineering specialties of military colleges and universities.[Chinese Medical Equipment Journal,2023,44(9):92-95]
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Objective To propose a method for predicting weaning outcomes based on machine learning and electrical impedance tomography(EIT).Methods Firstly,EIT image features were extracted from a total of 84 samples from 30 patients,and the important features screened with the extreme gradient boosting(XGBoost)algorithm were used as inputs to the model.Secondly,the prediction model was built with six machine learning methods,namely random forest(RF),support vector machines(SVM),XGBoost,gradient boosting decision tree(GBDT),logistic regression(LR)and decision tree(tree).Then the prediction model had its prediction performance evaluated by AUC,accuracy,sensitivity and specificity under imbalanced dataset,over-sampling balanced dataset and random under-sampling balanced dataset.Results In terms of AUC,accuracy and specificity,the model under the over-sampling balanced dataset and the random under-sampling balanced dataset behaved better than that under the imbalanced dataset(P＜0.05);in terms of sensitivity,the difference in model performance between the over-sampling balanced dataset and the imbalanced dataset was not statistically significant(P＞0.05),and the model performance under the random under-sampling balanced dataset decreased when compared with that under the imbalanced dataset(P＜0.05).There were no significant differences between the model performance under the over-sampling balanced dataset and that under the random under-sampling balanced dataset(P＞0.05).The model based on XGBoost behaved the best under the over-sampling balanced dataset,with an AUC of 0.769,an accuracy of 0.808,a sensitivity of 0.938 and a specificity of 0.600.Conclusion The method based on machine learning and EIT predicts weaning outcomes of patients with prolonged mechanical ventilation,and thus can be used for auxiliary decision support for clinicians to determine the appropriate timing of weaning.[Chinese Medical Equipment Journal,2023,44(10):1-6]
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Objective:To establish an antimony cerium catalytic spectrophotometric method for determination of iodine in water (referred to as the new method).Methods:Using the fading reaction principle of iodine catalyzed kinetics of antimony cerium to determine the iodine content in water. Methodological evaluations were conducted on the linear relationship, quantitative detection limit, precision, and accuracy (determination of national water iodine first level standard substances GBW09113f, GBW09114f, and addition recovery experiments) of the new method within the range of 0 to 100 μg/L iodine mass concentration. And the method was compared with the determination results of water iodine by arsenic cerium catalytic spectrophotometry recommended by the national iodine reference laboratory (NRL).Results:Within the range of 0 - 100 μg/L iodine mass concentration, the curve correlation coefficient of the new method was greater, and | r| > 0.999 0, and the quantitative detection limit was 0.15 μg/L (the sampling volume was 1 ml), the relative standard deviation of the detection precision of water samples with low, medium and high iodine mass concentrations were less than 2%. The new method had determined the average values of national water iodine first level standard substances GBW09113f and GBW09114f were 8.32 and 54.54 μg/L, respectively, all within the standard value range. The recovery range of standard addition was 92.6% - 99.2%, and the total average recovery was 96.4%. Compared with the NRL recommended method, the difference was not statistically significant ( t = 0.99, P > 0.05). Conclusion:The new method does not require the use of highly toxic substance arsenic trioxide, has high reaction sensitivity and accuracy, and is suitable for the promotion and use of water iodine detection.
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Objective:To study the application of ammonium cerium sulfate spectrophotometry for determination of iodide in water.Methods:Ammonium cerium sulfate spectrophotometry was used to determine the iodine content of tap water and source water in the range of 0 - 20 and 0 - 200 μg/L iodine concentration. The effect of the method was verified in terms of linear range, detection limit, precision and accuracy.Results:In the range of 0 - 20 and 0 - 200 μg/L iodine concentration, the absolute values of linear correlation coefficients were > 0.999 0; the detection limits were 0.18 and 1.02 μg/L, respectively; the coefficient of variation of low, medium and high iodine concentrations in tap water and source water was less than 5%. In the range of 0 - 20 μg/L iodine concentration, the spiked recovery rates of tap water and source water were 90.33% - 110.46% and 92.21% - 102.82%, respectively; in the range of 0 - 200 μg/L iodine concentration, the spiked recovery rates of tap water and source water were 90.14% - 102.62% and 91.36% - 106.18%, respectively. The national first level standard materials GBW09113g and GBW09114g were tested, and the results of water iodine determination were within the given range of the standard materials.Conclusion:Ammonium cerium sulfate spectrophotometry has a wide linear range, high accuracy, and good precision, making it suitable for widespread application in grassroots areas.
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Objective:To study the application of antimony cerium catalytic spectrophotometry using a fully automatic biochemical analyzer (hereinafter referred to as this method) in the determination of water iodine.Methods:Based on the principle of antimony cerium reoxidation reduction reaction catalyzed by iodine, the iodine content in water was determined in the range of 0 - 100 μg/L iodine mass concentration. The detection limit, precision and accuracy (determination of standard substances GBW09113j and GBW09114j for iodine composition analysis in water and the experiment of standard recovery) of this method were verified. This method was compared with the arsenic and cerium catalytic spectrophotometry recommended by the National Reference Laboratory for Iodine Deficiency Disorders.Results:Within the range of 0 - 100 μg/L iodine mass concentration, the qualitative and quantitative detection limits of this method were 0.81 and 2.70 μg/L, respectively (sampling quantity was 35 μl). In the precision experiment, the relative standard deviation of water samples with different iodine mass concentrations ranged from 1.2% to 4.0%. The determination results of the standard substances GBW09113j and GBW09114j for iodine composition analysis in water were both within the given standard value range. The standard recovery rates of water samples with low, medium and high iodine mass concentrations ranged from 101.0% to 106.0%, and the total average standard recovery rate was 103.2%. The results of the method comparison experiment showed that there was no statistically significant difference in the results of water iodine determination between the two methods ( t = - 0.78, P = 0.779). Conclusion:This method has a low detection limit, high precision and good accuracy, making it suitable for the detection of large quantities of samples in the monitoring of iodine deficiency disorders.
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Objective:To investigate the curative effect of transfer of free anteriolateral thigh flap (ALTF) with partial iliotibial tract on reconstruction of composite tissue defects in dorsal wrist/hand.Methods:Ten patients who were admitted in the Department of Hand Surgery of Yongkang Orthopaedic Hospital from March 2018 to August 2022 were entered in the study due to extensive composite tissue defects in dorsal wrists and hands. The patients were 24-48 (37 in average) years old. All patients had tendon defects in 3 or more digits with 35 digits in total. The length of the tendon defects were 5.0-11.0 cm in various digits. The soft tissue defects ranged from 6.0 cm×8.0 cm to 11.0 cm×21.0 cm in size. Six patients had defects accompanied with metacarpal and phalangeal bone fracture and joint capsule. In emergency surgery, all patients received thorough debridement and VSD coverage after internal fixation for combined fractures. At 3-5 days after the primary surgery, free ALTF transfer with partial iliotibial tract was employed to reconstruct the defects on dorsal wrists and hands and the digit extension function. The size of flap was 6.0 cm×9.0 cm-9.0 cm×17.0 cm, and the rest of defect wound was covered by skin graft. All the donor sites were sutured directly, except 1 that received abdominal skin graft. Patients had the follow-ups in outpatient clinics, or via telephone or Wechat, to observe the sensation and appearance of the flap, and the healing of the donor site. The recovery of the extension function of the hand was evaluated according to the totle active motion (TAM) system.Results:All flaps survived except one that had vascular compromise after the surgery and it survived after two explorations and a vascular transfer. Postoperative follow-ups lasted for 6 to 24 months, with 13 months in average. At the last follow-up, a all the flaps were found soft in texture and slightly swollen in appearance. There was no obvious pigmentation or rupture of skin and extensor tendon. Sensory recovery achieved to S 2 in 7 patients and S 3 in 3 patients. The hand function was evaluated according to TAM system and rated as excellent for 3 digits, good for 18 digits, fair for 9 digits and poor for 5 digits. There were linear scars in the donor sites. Conclusion:Free ALTF transfer with partial iliotibial tract in the reconstruction of composite tissue defect of dorsal wrists and hands can not only reconstruct the wound surface, but also the extension of digits, which cuts short the course of treatment.
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Background@#Open rhinoplasty and septoplasty have emerged as popular surgical techniques for both functional and aesthetic procedures. To study open rhinoplasty with or without septoplasty, the use of animals is necessary. However, no reports have been published on radiologic methods for evaluating rhinoplasty or nasal tip plasty in animals using cephalometry. In this study, a validated model of open rhinoplasty and septoplasty was utilized in rabbits to establish radiographic guidelines for assessing the degree of tip plasty in these animals. @*Methods@#Eight adult New Zealand rabbits were used to establish an autologous septal extension graft (SEG) model. The rabbits underwent concurrent submucosal septal resection and open rhinoplasty. The SEG was implanted using nasal septal cartilage. To evaluate the results of nasal tip plasty, lateral-view X-ray images were obtained preoperatively, as well as 2 days, 2 months, and 12 months postoperatively. @*Results@#This open rhinoplasty rabbit model appears to be a practical tool for studying open rhinoplasty and tip plasty, demonstrating statistically significant results following SEG implantation. Furthermore, it is suitable for training purposes, specifically for the submucosal resection of septal cartilage. @*Conclusions@#This study presents a statistical analysis of the long-term (1-year) postoperative results of SEG implantation, using experimental procedures like those utilized in humans. Through a cephalometric comparison of rabbit noses, the effect of various SEG and tip plasty methods on the rabbit nose can be objectively measured.
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Endotracheal intubation is often necessary in the course of animal experiments, especially in craniofacial surgery. However, endotracheal intubation can be a major burden in this context. The authors performed simple and cost-saving method using a 200 μL yellow micropipette tip, and the success of this method was demonstrated by X-ray and autopsy. We used a total of 30 rats. After the rats were fixed with a plaster, the trachea and vocal cords were visualized with the tongue pulled back. Under direct visualization of the vocal cords, a curving micropipette tip was advanced into the trachea. This method can be learned quickly and applied successfully by general experimenters. We successfully intubated all 30 rats without any complications. The success rate of micropipette tip intubation was 100%. This procedure was performed by one experimenter within 2 to 3 minutes after induction of anesthesia. We demonstrated its superiority by X-ray and autopsy. Herein, we describe endotracheal intubation of rats using micropipette tips. To the best of our knowledge, this method is novel and represents the simplest and most efficient means of intubation in rats, providing an alternative to conventional endotracheal intubation.
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An intraosseous hemangioma of the frontal bone is typically removed via a coronal incision. This procedure, while effective, can be lengthy and may result in complications such as a prominent scar and hair loss. An alternative approach involves a direct incision in the forehead, which leaves a less noticeable scar and allows a quicker recovery. However, in this specific case, the patient declined both coronal surgery and surgery through a direct forehead incision due to cosmetic concerns. Therefore, we proposed an anterior hairline incision. A 35-year-old woman presented with a firm, non-mobile, palpable mass on her right forehead. Preoperative non-contrast computed tomography revealed a heterogeneous osteolytic lesion. We performed an excisional biopsy through the anterior hairline. Postoperative non-contrast computed tomography was conducted 2 and 6 months after surgery. The wound was clean and free of complications, and there was no local recurrence. Partial resection can reduce scarring for patients who are concerned about cosmetic outcomes. However, the potential for recurrence remains a significant concern. We present this case of an anterior hairline incision for a hemangioma located in the forehead, evaluated using serial computed tomography for both preoperative and postoperative imaging.
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The areola is a rare location for squamous cell carcinoma (SCC) because sunlight exposure, the main risk factor for SCC, is unusual on it. Acantholytic SCC (ASCC) is a rare histologic variant of SCC, characterized by pseudoglandular appearance with acantholytic tumor cells. A 59-year-old male presented a painful erythematous papule on his right areola. He had a history of psoralen ultraviolet A phototherapy for psoriasis in his 20s. Biopsy revealed an epithelial tumor and pseudoglandular structures with acantholytic tumor cells. In immunohistochemistry, cytokeratin 5/6, epithelial membrane antigen, and p63 were positive, while cytokeratin 7, carcinoembryonic antigen, S-100, and estrogen and progesterone receptors were negative. Periodic acid-Schiff stain was negative. Ki-67 labeling index was 79.7%. The final diagnosis was ASCC of the areola. After wide local excision, recurrence have not been reported. Here, we report a case of ASCC on the areola, focusing on its rare histologic variant and uncommon location.
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Background@#We investigated the extent of regional disparity of recurrent falls. In addition, we examined the association between particulate matter (PM) and recurrent falls and the association between regional disparity of recurrent falls and regional PM levels.Method: We used data from Korea Community Health Survey 2019 that included 204,395 participants from 237 municipal districts. The independent variables were the annual average PM10 and PM2.5 concentrations measured at the air quality measuring stations in each municipal district. The outcome variable was the experience of falls more than twice in the previous year. Multilevel analyses were conducted to estimate the association between regional PM10 and PM2.5 levels and recurrent falls. @*Results@#The regional variation was greater in the young people than that in the older people. PM10 and PM2.5 levels were positively associated with recurrent falls after adjusting for individual and regional covariates. These associations were more evident in the older group than in the young. PM10 and PM2.5 explained 2.82% and 3.33% of the remaining regional variance in models with individual and regional confounders, respectively. These proportions were greater in the older group (PM10 and PM2.5; 4.73% and 5.27%) than those in the younger age group (PM10 and PM2.5, 0.80% and 1.39%). @*Conclusion@#PM concentration was associated with recurrent falls even after accounting for other regional variables and individual-level differences. Moreover, there were regional differences in the occurrence of falls, and the PM concentration explained a part of the gap, but the gap was explained more in the older group than in the young