Association of the Japanese herbal kampo medicine kakkonto with antibiotic use and surgical drainage for noninfectious mastitis: A nationwide database study.

AIM: Kakkonto, a Japanese herbal kampo medicine, is empirically prescribed to improve milk stasis and ameliorate breast inflammation in patients with noninfectious mastitis. We investigated whether early use of kakkonto is associated with a reduction in antibiotic use and surgical drainage in patients with noninfectious mastitis. METHODS: We identified 34 074 patients with an initial diagnosis of noninfectious mastitis within 1 year of childbirth between April 2012 and December 2022 using the nationwide administrative JMDC Claims Database. Patients were divided into the kakkonto (n = 9593) and control (n = 9648) groups if they received and did not receive kakkonto on the day of the initial diagnosis of noninfectious mastitis, respectively. Antibiotic administration and surgical drainage within 30 days after the initial diagnosis of noninfectious mastitis in the two groups were compared using propensity score-stabilized inverse probability of treatment weighting analysis. RESULTS: The frequency of antibiotic administration within 30 days after the initial diagnosis of noninfectious mastitis was significantly lower in the kakkonto group than in the control group (10% vs. 12%; odds ratio, 0.88 [95% confidence interval, 0.80-0.96]). The frequency of antibiotic administration during 1-3 and 4-7 days after the initial diagnosis were also significantly lower in the kakkonto group than in the control group. The frequency of surgical drainage did not differ significantly between the two groups. CONCLUSIONS: Kakkonto was associated with reduced administration of antibiotics for noninfectious mastitis, making it a potential treatment option for relieving breast inflammation and promoting antimicrobial stewardship.

Changes in Demand Volume and Patient/Health Care Provider Characteristics of First-Time Telehealth Users: A Comparative Analysis Before and After the COVID-19 Policy Response Using the Administrative Claims Database.

Introduction: The COVID-19 pandemic has led to a decrease in demand for medical services in Japan, but the utilization of telehealth, which the Japanese government has recently promoted, has seen a temporary increase. This study aims to analyze the trend of telehealth utilization and changes in patient characteristics following the policy response to COVID-19. Methods: This retrospective study analyzed data from 26,152 adult patients who used telehealth for the first time between April 2019 and April 2021 in Mie Prefecture, Japan. An interrupted time series analysis was conducted to evaluate changes in the number of first-time patients before and after April 2020. Results: The number of telehealth users increased by 111.87% after April 2020, but the trend showed a declining slope thereafter. Patient characteristics and disease types showed different trends. The percentage of patients choosing a hospital over a clinic increased for the first time. Conclusions: After the policy response to COVID-19, the number of first-time telehealth users overall increased immediately, but gradually showed a declining trend. However, some diseases have shown both an immediate increase and a continued upward trend in telehealth utilization. Patients with these diseases may be candidates for adopting telehealth services in clinical settings.

Optimal allocation of physicians improves accessibility and workload disparities in stroke care.

BACKGROUND: Inequalities in access to stroke care and the workload of physicians have been a challenge in recent times. This may be resolved by allocating physicians suitable for the expected demand. Therefore, this study analyzes whether reallocation using an optimization model reduces disparities in spatial access to healthcare and excessive workload. METHODS: This study targeted neuroendovascular specialists and primary stroke centers in Japan and employed an optimization model for reallocating neuroendovascular specialists to reduce the disparity in spatial accessibility to stroke treatment and workload for neuroendovascular specialists in Japan. A two-step floating catchment area method and an inverted two-step floating catchment area method were used to estimate the spatial accessibility and workload of neuroendovascular specialists as a potential crowdedness index. Quadratic programming has been proposed for the reallocation of neuroendovascular specialists. RESULTS: The reallocation of neuroendovascular specialists reduced the disparity in spatial accessibility and the potential crowdedness index. The standard deviation (SD) of the demand-weighted spatial accessibility index improved from 125.625 to 97.625. Simultaneously, the weighted median spatial accessibility index increased from 2.811 to 3.929. Additionally, the SD of the potential crowdedness index for estimating workload disparity decreased from 10,040.36 to 5934.275 after optimization. The sensitivity analysis also showed a similar trend of reducing disparities. CONCLUSIONS: The reallocation of neuroendovascular specialists reduced regional disparities in spatial accessibility to healthcare, potential crowdedness index, and disparities between facilities. Our findings contribute to planning health policies to realize equity throughout the healthcare system.

Monthly trends and seasonality of hemodialysis treatment and outcomes of newly initiated patients from the national database (NDB) of Japan.

BACKGROUND: The numbers of patients treated with hemodialysis (HD) in Japan are currently quantified by manual survey. As this method requires much effort from medical institutions and cannot achieve 100% response, a more practical method is required. We aimed to establish a novel method for determining the static and dynamic numbers of patients treated with HD. METHODS: This observational study used the national medical billing database (termed NDB) of Japan, based on the records of the universal healthcare insurance system. Medical billing data registered in the NDB between April 2011 and March 2015 were analyzed. From 130 billion records, we extracted and analyzed records of patients who had undergone HD at least once per month. Patients' monthly condition was classified as newly initiated HD, chronic HD, or presumed death, using conditional expressions. We also investigated renal outcome and presumed survival in newly initiated HD patients. RESULTS: In the last month of the study period, 274,100 patients were identified as receiving chronic HD, which is estimated as > 95% of the number of these patients identified in the manual survey so far. The monthly data showed clear seasonality in the incidence of transient HD, which increased in winter and decreased in summer. CONCLUSION: Analysis of a large national database revealed a significant increase in transient HD in winter and decrease in summer. Applied to additional epidemiological exploratory studies or clinical research, this analytical technique would enable collection of the dynamics of almost all HD patients nationwide.

Predicting demand for long-term care using Japanese healthcare insurance claims data.

BACKGROUND: Driven by the rapid aging of the population, Japan introduced public long-term care insurance to reinforce healthcare services for the elderly in 2000. Precisely predicting future demand for long-term care services helps authorities to plan and manage their healthcare resources and citizens to prevent their health status deterioration. METHODS: This paper presents our novel study for developing an effective model to predict individual-level future long-term care demand using previous healthcare insurance claims data. We designed two discriminative models and subsequently trained and validated the models using three learning algorithms with medical and long-term care insurance claims and enrollment records, which were provided by 170 regional public insurers in Gifu, Japan. RESULTS: The prediction model based on multiclass classification and gradient-boosting decision tree achieved practically high accuracy (weighted average of Precision, 0.872; Recall, 0.878; and F-measure, 0.873) for up to 12 months after the previous claims. The top important feature variables were indicators of current health status (e.g., current eligibility levels and age), risk factors to worsen future healthcare status (e.g., dementia), and preventive care services for improving future healthcare status (e.g., training and rehabilitation). CONCLUSIONS: The intensive validation tests have indicated that the developed prediction method holds high robustness, even though it yields relatively lower accuracy for specific patient groups with health conditions that are hard to distinguish.

Projecting supply and demand for pharmacists in pharmacies based on the number of prescriptions and system dynamics modeling.

BACKGROUND: Pharmacists play an important role in promoting people's health in Japan, which has an aging population. Hence, it is necessary that the distribution of pharmacists meets the population's needs in each region. This study projects the future supply and demand for pharmacists in pharmacies to consider an optimal distribution of pharmacists. METHODS: The future supply of pharmacists working in pharmacies in Hokkaido is projected using system dynamics modeling, according to their career path. The demand is projected based on the number of prescriptions, sourced from publicly available sources. The analysis period is 2015-2040. The estimated demand is converted into the number of pharmacists and the sufficiency is evaluated using sufficiency ratio (supply/demand ratio). Sensitivity analyses of the sufficiency ratio were conducted to estimate the effects of changes in parameters such as national exam pass rate, enrollments, attrition rates, the number of prescriptions per pharmacist, and diffusion of newly licensed pharmacists. RESULTS: The projected supply, in 2025 and 2040, is 1.24 and 1.56 times, respectively, as that in 2015 and the demand is 1.11 and 0.98 times, respectively. In 2015, although the sufficiency ratio in Hokkaido overall is 1.19, the ratios are higher in urban medical areas and lower than 1 in rural medical areas, such as Minamihiyama, Emmon, and Nemuro. By 2040, the sufficiency ratios are greater than 1 for all areas except for Emmon and higher than 2 in some areas. The sensitivity analyses found that the sufficiency ratio was most sensitive to diffusion of newly licensed pharmacists and the number of prescriptions per pharmacist. CONCLUSION: Optimal distribution should be considered, as the results reveal a possible shortage in the number of pharmacists in rural medical areas in 2015-2025. Conversely, as the demand is projected to decrease after 2025 with a population decrease, future supply should be determined in order not to cause an oversupply after 2025. Refinements of the projection model should be conducted since the related factors such as the roles of pharmacists will change over time.

Cost-Effectiveness of a Continuous Glucose Monitoring Mobile App for Patients With Type 2 Diabetes Mellitus: Analysis Simulation.

BACKGROUND: Apps for real-time continuous glucose monitoring (CGM) on smartphones and other devices linked to CGM systems have recently been developed, and such CGM apps are also coming into use in Japan. In comparison with conventional retrospective CGM, the use of CGM apps improves patients' own blood glucose control, which is expected to help slow the progression of type 2 diabetes mellitus (DM) and prevent complications, but the effect of their introduction on medical costs remains unknown. OBJECTIVE: Our objective in this study was to perform an economic appraisal of CGM apps from the viewpoint of assessing public medical costs associated with type 2 DM, using the probability of developing type 2 DM-associated complications, and data on medical costs and utility value to carry out a medical cost simulation using a Markov model in order to ascertain the cost-effectiveness of the apps. METHODS: We developed a Markov model with the transition states of insulin therapy, nephrosis, dialysis, and cardiovascular disease, all of which have a major effect on medical costs, to identify changes in medical costs and utility values resulting from the introduction of a CGM app and calculated the incremental cost-effectiveness ratio (ICER). RESULTS: The ICER for CGM app use was US $33,039/quality-adjusted life year (QALY). CONCLUSIONS: Sensitivity analyses showed that, with the exception of conditions where the transition probability of insulin therapy, utility value, or increased medical costs increases, the ICER for the introduction of CGM apps was below the threshold of US $43,478/QALY used by the Central Social Insurance Medical Council. Our results provide basic data on the cost-effectiveness of introducing CGM apps, which are currently starting to come into use.

Cost comparison between open radical cystectomy, laparoscopic radical cystectomy, and robot-assisted radical cystectomy for patients with bladder cancer: a systematic review of segmental costs.

BACKGROUND: Robot-assisted radical cystectomy is becoming a common treatment for bladder carcinoma. However, in comparison with open radical cystectomy, its cost-effectiveness has not been confirmed. Although few published reviews have compared total costs between the two surgical procedures, no study has compared segmental costs and explained their impact on total costs. METHODS: A systematic review was conducted based on studies on the segmental costs of open, laparoscopic, and robot-assisted radical cystectomy using PubMed, Web of Science, and Cochrane Library databases to provide insight into cost-effective management methods for radical cystectomy. The segmental costs included operating, robot-related, complication, and length of stay costs. A sensitivity analysis was conducted to determine the impact of the annual number of cases on the per-case robot-related costs. RESULTS: We identified two studies that compared open and laparoscopic surgeries and nine that compared open and robotic surgeries. Open radical cystectomy costs were higher than those of robotic surgeries in two retrospective single-institution studies, while robot-assisted radical cystectomy costs were higher in 1 retrospective single-institution study, 1 randomized controlled trial, and 4 large database studies. Operating costs were higher for robotic surgery, and accounted for 63.1-70.5% of the total robotic surgery cost. Sensitivity analysis revealed that robot-related costs were not a large proportion of total surgery costs in institutions with a large number of cases but accounted for a large proportion of total costs in centers with a small number of cases. CONCLUSIONS: The results show that robot-assisted radical cystectomy is more expensive than open radical cystectomy. The most effective methods to decrease costs associated with robotic surgery include a decrease in operating time and an increase in the number of cases. Further research is required on the cost-effectiveness of surgeries, including quality measures such as quality of life and quality-adjusted life years.

Forecasting maldistribution of human resources for healthcare and patients in Japan: a utilization-based approach.

BACKGROUND: Hokkaido's demographic trend of population decrease with aging population is remarkable even in Japan. Although healthcare policy decision-makers need to appropriately allocate resources while grasping regional demands, not much is available on whether medical demand would increase or not for future. In addition, little is known about what impact will current situation have on future demand-supply balance and equality by regions. This study aims to support decision-making in human resource planning for coping with changing population structure by forecasting future demand, and evaluation those regional maldistributions. METHOD: We set patients with acute myocardial infarction or cerebral stroke, and all medical care as study subjects and analyzed for 2015, 2025, and 2035 in Hokkaido and each Secondary Medical Care Area. We used a utilization-based approach to estimate the healthcare supply-demand balance in the future. Moreover, we evaluated the regional maldistribution of demand-supply balance by calculating Herfindahl-Hirschman Index, Gini Coefficients, the number of physicians/specialists per patient. Moreover, we conducted sensitivity analysis to evaluation impact on aspects of demand-supply balance by uncertainty of utilization for future. RESULTS: Our results displayed that concentration of patients will progress, while regional distribution will shrink in all subject. However, from comparison based on all medical care, Gini Coefficients of acute myocardial infarction and cerebral stroke has always been high. This suggest that the resource allocation of them has room for improvement. In addition, our analysis showed the change in this balance will differ in each region in the future. Moreover, demographic change will not consistent with the number of patient change from 2015 to 2035. CONCLUSION: These results suggest policy planners should use the number of patient by disease, by region as indicator of demand, instead of provider-to-population ratios being in use today. The result of our sensitivity analysis show two findings. First, the range of each indicator have possible for future. Second, increase of utilization, for instance lowing barrier in the use by development operation of patient transportation in AMI/CS, would improve maldistribution of opportunity for resident to get emergency medical services.

Where Does Telemedicine Achieve a Cost Reduction Effect? Cost Minimization Analysis of Teleradiology Services in Japan.

Background: Telemedicine as a technology is expected to resolve issues such as doctor shortages and disparities in medical services. However, high costs of system installation and maintenance inhibit its widespread use.Introduction: This study involved a cost minimization analysis for installation of a teleradiology system in the Hokkaido prefecture of Japan. Conditions under which system utilization is cost-efficient and system utilization is effective for cost reduction were analyzed.Materials and Methods: A cost minimization analysis was conducted using three geospatial points of 50, 100, and 200 km from Sapporo city, the prefectural capital of Hokkaido, assuming a central imaging diagnosis center in Sapporo. The analysis was conducted from the standpoint of both patients and requesting hospitals.Results: From the patient's standpoint, a cost reduction effect was observed at all three distances from system installation. In contrast, from the hospital's standpoint, a cost reduction effect was found only when teleradiology examination was conducted from a distance of at least 100 km from Sapporo.Discussion: Results show that the cost reduction effect for patients increased as the travel distance increased. Although the teleradiology service is beneficial for a wide range of patients, the financial burden on requesting hospitals is significant.Conclusions: The following conditions were found necessary to reduce the requesting hospital's financial burden: the hospital should be far from the imaging diagnosis center, an inexpensive system is to be selected, and the system needs to be utilized continuously.

Cost Effectiveness of Drive and Retrieve System in Hokkaido for Acute Ischemic Stroke Patient Treatment Using Geographic Information System.

BACKGROUND AND PURPOSE: Although endovascular thrombectomy combined with recombinant tissue-type plasminogen activator is effective for treatment of acute ischemic stroke, regional disparities in implementation rates of those treatments have been reported. Drive and retrieve system, where a qualified neurointerventionist travels to another primary stroke center for endovascular thrombectomy, has been practiced in parts of Hokkaido, Japan. This study aims to simulate the cost effectiveness of the drive and retrieve system, which can be a method to enhance equality and cost effectiveness of treatments for acute ischemic stroke. MATERIALS AND METHODS: The number of patients who had acute ischemic stroke in 2015 is estimated. Those patients are generated according to the population distribution, and thereafter patient transport time is analyzed in the 3 scenarios (1) 60-minute drive scenario, (2) 90-minute drive scenario, in which the drive and retrieve system operates within 60-minute or 90-minute driving distance (3) without the system, using geographic information system. Incremental cost-effectiveness rate, quality-adjusted life years, and medical and nursing care costs are estimated from the analyzed transport time. FINDINGS: The incremental cost-effectiveness rate by implementing the system was dominant. Cost reductions of $213,190 in 60-minute drive scenario, and $247,274 in the 90-minute scenario were expected, respectively. Such benefits are the most significant in Soya, Emmon, Rumoi, and Kamikawahokubu medical areas. CONCLUSIONS: The drive and retrieve system could enhance regional equality and cost effectiveness of ischemic stroke treatments in Hokkaido, which can be achieved using existing resources. Further studies are required to clarify its cost effectiveness from hospital perspective.

Forecasting the regional distribution and sufficiency of physicians in Japan with a coupled system dynamics-geographic information system model.

BACKGROUND: In Japan, the shortage of physicians has been recognized as a major medical issue. In our previous study, we reported that the absolute shortage will be resolved in the long term, but maldistribution among specialties will persist. To address regional shortage, several Japanese medical schools increased existing quota and established "regional quotas." This study aims to assist policy makers in designing effective policies; we built a model for forecasting physician numbers by region to evaluate future physician supply-demand balances. METHODS: For our case study, we selected Hokkaido Prefecture in Japan, a region displaying disparities in healthcare services availability between urban and rural areas. We combined a system dynamics (SD) model with geographic information system (GIS) technology to analyze the dynamic change in spatial distribution of indicators. For Hokkaido overall and for each secondary medical service area (SMSA) within the prefecture, we analyzed the total number of practicing physicians. For evaluating absolute shortage and maldistribution, we calculated sufficiency levels and Gini coefficient. Our study covered the period 2010-2030 in 5-year increments. RESULTS: According to our forecast, physician shortage in Hokkaido Prefecture will largely be resolved by 2020. Based on current policies, we forecast that four SMSAs in Hokkaido will continue to experience physician shortages past that date, but only one SMSA would still be understaffed in 2030. CONCLUSION: The results show the possibility that diminishing imbalances between SMSAs would not necessarily mean that regional maldistribution would be eliminated, as seen from the sufficiency levels of the various SMSAs. Urgent steps should be taken to place doctors in areas where our forecasting model predicts that physician shortages could occur in the future.

[Tooth Mobility Evaluation -A Comparison with Dental Assessment-].

BACKGROUND: Patients with mobile teeth are at an increased risk of tooth injury related to tracheal intu- bation. Although the presence/absence of mobile teeth is confirmed through interviews during preoperative visits, patients are frequently unaware of the presence of such teeth. In our facility, dental consultation is pro- vided for all patients undergoing thoracoscopically- assisted surgery as part of the management of oral hygiene. This study examined the presence/absence of mobile teeth reported by patients during preoperative visits and those identified on dental consultation, focus- ing on the inconsistency between them. METHODS: Patients who had undergone thoraco- scopically-assisted surgery in our facility between Janu- ary and October 2014 were retrospectively studied. Tooth mobility was evaluated using the Miller index. RESULTS: Among the 76 (46 males and 30 females) patients aged 36 to 88 (mean: 67.8), mobile teeth were identified on dental consultation in 13 and reported during preoperative visits by 8. CONCLUSIONS: Based on this findings, it may be nec- essary to pay sufficient attention when inserting tubes even when mobile teeth have not been reported by patients during preoperative visits.

[Anesthesia in a Patient with Giant Goiter in Whom Tracheotomy Was Performed with Standby of Percutaneous Cardiopulmonary Support].

In a 53-year-old female patient total thyroidectomy for a giant goiter under general anesthesia was scheduled. On talking, airway stenosis sounds were heard. Cervical to thoracic CT revealed left and right lobe tumors measuring 5.3 x 5.6 x 10.0 and 9.1 x 8.6 x 10.0 cm, respectively. The trachea showed stenosis at a site 3.8 to 6.5 cm below the glottis, and the narrowest lumen diameter was 3.1 mm. Due to marked tracheal stenosis, awake intubation was not selected. To maintain the airway, tracheotomy was performed under local anesthesia. Considering the risk of difficulty in ventilation during tracheostomy, 4 Fr catheter sheaths were inserted into the right femoral artery and vein for percutaneous cardiopulmonary support (PCPS). Subsequently, tracheotomy was conducted in an area peripheral to the site of stenosis. After tracheotomy, general anesthesia was started. During general anesthesia, there were no problems regarding ventilation. The tracheal cannula was removed 7 days after surgery, and the patient was discharged after 14 days. For general anesthesia in patients with giant goiter, it is important to select an airway management method in consideration of tumor-related compression of the trachea. Airway management by tracheotomy under local anesthesia with standby of PCPS may be a treatment option.

[Perioperative Management of Emergency Operation for a Patient with Carcinoid Syndrome].

We report a case of carcinoid syndrome requiring an emergency operation for an upper gastrointestinal perforation. A 46-year-old man had undergone left lower lobectomy for a lung carcinoid tumor seven years previously, and liver metastasis was found five years previously. He developed cutaneous flushing and watery diarrhea, and was diagnosed with carcinoid syndrome one year previously. Although he was treated with octreotid, his symptoms became worse and he was admitted to our hospital. During the hospital stay, he underwent an emergency operation for an upper gastrointestinal perforation. Before the operation, hemodynamics were unstable. Anesthesia was induced with sevoflurane and propofol, and maintained with sevoflurane and remifentanil. Only vasopressin was used for the treatment of hypotension. Landiolol was used for perioperative tachyarrythmia. During anesthesia, there was no severe hypotension or hypertension. After the operation, he was managed with intubation in the ICU. Octreotid was administered again for the carcinoid syndrome. Vasopressin was necessary for the treatment of hypotension in the ICU. After improvement of hemodynamics, extubation was performed on the 3rd ICU day and he was discharged from the ICU on the 4th ICU day. In conclusion, we were able to perform good perioperative management of carcinoid syndrome accompanied by hemodynamic instability.

[General Anesthesia for the Thoracoscopic Lung Resection Surgery in 12 Very Elderly Patients above 85 Years of Age].

We investigated perioperative management and clinical outcome of 12 patients who were 85 years old or older and received video-assisted thoracic surgery under general anesthesia. Although all the patients had preoperative respiratory complications or cardiovascular complications, they were discharged without any additional respiratory assistance such as home oxygen therapy. Our observation suggests that it is important to evaluate the indication of anesthesia from their daily activities and pulmonary function test even if they are oldest-old. If the patient demonstrates good physical function, he or she should not be excluded from anesthesia.

Analyzing Patient-Sharing Network Using an Administrative Claim Database in Japan.

We analyzed the behavior of patient with a focus on patient-sharing based on the methodology of network analysis. We used an administrative healthcare claims database from September of the years 2008-2020 to identify shared patients with hypertension. The patients' behavior of visiting multiple medical facilities was extracted as graphical data, and we calculated density and centrality as indicators to evaluate the structure of the patient sharing network. Our findings indicate that density, reciprocity, and transitivity increased over time, and that centrality and PageRank were correlated.

Factors associated with the introduction of visiting-pharmacist services in older adults in Japan: A nested case-control study.

AIM: To investigate the factors associated with introducing visiting-pharmacist services for community-dwelling older adults in Japan. METHODS: We conducted a nested case-control study using claims data in a cohort from a city in Tokyo. Patients aged ≥65 years who received visiting-pharmacist services for the first time between April 2014 and March 2020 were considered case patients. A maximum of four controls to each case patient were randomly selected on the basis of sex, age, health insurance systems, and month-year. Medical and long-term care service usage and patient condition were assessed using claims data from the index and preceding months, along with long-term care needs certification data. Multivariable conditional logistic regression analysis was conducted to estimate the adjusted odds ratios with 95% confidence intervals for factors associated with visiting-pharmacist service introduction. RESULTS: A total of 22 949 participants (4591 cases and 18 358 controls) were included, with a median age of 85 years; 59.3% were women. The adjusted odds ratios (95% confidence intervals) of the three most related factors were 27.61 (23.98-31.80) for physicians' home visits, 5.83 (5.08-6.70) for hospitalization, and 4.97 (4.16-5.95) for designated-facility admission. Factors such as prescribing ≧10 medications, visiting nursing, and cancer were positively associated. In contrast, low household income and a high need for support due to cognitive function or disability were negatively associated. CONCLUSIONS: This study provides insights into the introduction of visiting-pharmacist services for older adults in Japan. Geriatr Gerontol Int 2024; 24: 344-351.

Twist2 functions as a tumor suppressor in murine osteosarcoma cells.

The epithelial-mesenchymal transition (EMT) contributes to the malignant progression of cancer cells including acquisition of the ability to undergo metastasis. However, whereas EMT-related transcription factors (EMT-TF) are known to play an important role in the malignant progression of epithelial tumors, their role in mesenchymal tumors remains largely unknown. We show that expression of the gene for Twist2 is downregulated in human osteosarcoma and correlates inversely with tumorigenic potential in mouse osteosarcoma. Forced expression of Twist2 in highly tumorigenic murine osteosarcoma cells induced a slight inhibition of cell growth in vitro but markedly suppressed tumor formation in vivo. Conversely, knockdown of Twist2 in osteosarcoma cells with a low tumorigenic potential promoted tumor formation in vivo, suggesting that Twist2 functions as a tumor suppressor in osteosarcoma cells. Furthermore, Twist2 induced expression of fibulin-5, which has been reported as a tumor suppressor. Medium conditioned by mouse osteosarcoma cells overexpressing Twist2 inhibited expression of the MMP9 gene as well as invasion in mouse embryonic fibroblasts, and forced expression of Twist2 in osteosarcoma cells suppressed MMP9 gene expression in tumor tissue. Data from the present study suggest that Twist2 inhibits formation of a microenvironment conducive to tumor growth and thereby attenuates tumorigenesis in osteosarcoma.

Forecasting the absolute and relative shortage of physicians in Japan using a system dynamics model approach.

BACKGROUND: In Japan, a shortage of physicians, who serve a key role in healthcare provision, has been pointed out as a major medical issue. The healthcare workforce policy planner should consider future dynamic changes in physician numbers. The purpose of this study was to propose a physician supply forecasting methodology by applying system dynamics modeling to estimate future absolute and relative numbers of physicians. METHOD: We constructed a forecasting model using a system dynamics approach. Forecasting the number of physician was performed for all clinical physician and OB/GYN specialists. Moreover, we conducted evaluation of sufficiency for the number of physicians and sensitivity analysis. RESULT & CONCLUSION: As a result, it was forecast that the number of physicians would increase during 2008-2030 and the shortage would resolve at 2026 for all clinical physicians. However, the shortage would not resolve for the period covered. This suggests a need for measures for reconsidering the allocation system of new entry physicians to resolve maldistribution between medical departments, in addition, for increasing the overall number of clinical physicians.