124 research outputs found
Formation of Protoplanets from Massive Planetesimals in Binary Systems
More than half of stars reside in binary or multiple star systems and many
planets have been found in binary systems. From theoretical point of view,
however, whether or not the planetary formation proceeds in a binary system is
a very complex problem, because secular perturbation from the companion star
can easily stir up the eccentricity of the planetesimals and cause
high-velocity, destructive collisions between planetesimals. Early stage of
planetary formation process in binary systems has been studied by restricted
three-body approach with gas drag and it is commonly accepted that accretion of
planetesimals can proceed due to orbital phasing by gas drag. However, the gas
drag becomes less effective as the planetesimals become massive. Therefore it
is still uncertain whether the collision velocity remains small and planetary
accretion can proceed, once the planetesimals become massive. We performed {\it
N}-body simulations of planetary formation in binary systems starting from
massive planetesimals whose size is about 100-500 km. We found that the
eccentricity vectors of planetesimals quickly converge to the forced
eccentricity due to the coupling of the perturbation of the companion and the
mutual interaction of planetesimals if the initial disk model is sufficiently
wide in radial distribution. This convergence decreases the collision velocity
and as a result accretion can proceed much in the same way as in isolated
systems. The basic processes of the planetary formation, such as runaway growth
and oligarchic growth and final configuration of the protoplanets are
essentially the same in binary systems and single star systems, at least in the
late stage where the effect of gas drag is small.Comment: 26pages, 11 figures. ApJ accepte
The quality of life among persons with severe mental illness enrolled in an assertive community treatment program in Japan: 1-year follow-up and analyses
BACKGROUND: Toward effective community care for persons with severe mental illness and deinstitutionalization in Japan, we assessed the impact of the first trial of an assertive community treatment program on the lives and subjective perceptions of persons with mental illness without closing hospitals. METHODS: Forty-three subjects were enrolled from the newly admitted patients of a hospital, who met our criteria of problematic hospital use, severity of psychiatric disorders, and behavioral problems. The intervention team aimed to intensively support them in various life domains in their communities to decrease clients' admissions. The Quality of Life Interview was administered at baseline and after 12 months. Data were analyzed to assess the pre-post changes in their QOL, and were explained in association with other descriptive variables. RESULTS: The objective changes included increase in persons whose longest residence in a year were in communities, increase in income, and decrease in family contacts. Most subjective items were not changed except the decrease in satisfaction with family relationships. Satisfaction with family relationships was negatively correlated with hospital days at 1 year follow-up after controlling for symptoms, but was not so at baseline. Also, correlation between satisfaction with family relationships and global well-being was attenuated. A change in the positioning of family by clients and the autonomy of clients were suggested. However, previous studies showed that dissatisfaction with family relationships predicted rehospitalizations independently from symptoms, and our findings suggest our subjects' characteristics and a possible improvement in community-based care. CONCLUSION: Our program predominantly fulfilled the primary goal, but it must be further refined to reflect the detailed characteristics of the target population and resource distribution. Assessing subjective perceptions, or the QOL of clients is useful for evaluating the program localization
Recent Developments in Community-Based Mental Health Care in Japan: A Narrative Review
BACKGROUND: Since the 1950s, mental health care in Japan has been hospital-centered. A set of legislative initiatives were undertaken in 1995, emphasizing the importance of community-based mental health care. However, despite these attempts to develop a community-based mental health care system, the rate of inpatient-based treatment has remained high and the shift from hospital-centered care to community-based has still not fully materialized.
AIM: This study aims to conduct a review of the available literature on the development of community-based mental health care in Japan between 2010 and 2020.
METHODS: We conducted a standardized literature search in the electronic database Igaku Chuo Zasshi, aiming to identify original studies published between 2010 and 2020 that explored community mental health care in Japan. The included studies outcomes were categorized as performance surveys, service user reports, service provider reports, and educational activities. A descriptive-analytical method was implemented in the current review.
RESULTS: A total of 25 studies were examined. Six studies reported surveys assessing the performance of community-based mental health care on the assertive community treatment (ACT), compulsory treatment, home-visit nursing care, physical complications, and a welfare medicine collaboration on a remote islands. Four studies investigated the perspectives of service users or their families on home-visit nursing care, social participation, community program, and legislative revision. Ten studies focused on social withdrawal, service providers perspectives on local population needs, supporting skills, care programs, and the professional growth of psychiatric social workers. Five studies focused on educational approaches for future healthcare professionals and efforts to improve mental health literacy among adolescents.
CONCLUSION: This paper provided the first comprehensive review of Japans community-based mental health care. Between 2010 and 2020, community mental health care in Japan evolved in many directions, with the understanding that various needs should be met. Home-visit nursing care and ACT can be considered as the most thoroughly investigated and better developed. Research that adopt rigorous methodologies such as randomized controlled trials is required if the goal is to achieve solid conclusions
Impact of Body Mass Index on Survival of Pancreatic Cancer Patients in Japan
The impact of body mass index (BMI) on postoperative survival in Japanese patients with pancreatic cancer is unclear. We examined the relationship between preoperative BMI and the prognosis of Japanese patients who underwent surgery for pancreatic cancer to determine whether BMI affects these patients’ prognosis. Of the patients who underwent pancreatectomy between January 2004 and August 2015 at our institution, 246 were pathologically diagnosed with pancreatic tubular adenocarcinoma; the cancer was located in the pancreatic head (n=161) and in the body and tail (n=85). We classified the patients by BMI: underweight (n=22), normal weight (n=190), and overweight/obese (n=34) groups. We retrospectively analyzed medical records for patient characteristics, lesion location, disease stage, postoperative complications, chemotherapy, and prognosis. Lesion location, disease stage, postoperative complications, and chemotherapy were not significantly different among the BMI groups. The median survival times were as follows (days): all patients, 686; underweight, 485; normal weight, 694; and overweight/obese, 839. In a multivariate analysis, after adjusting for competing risk factors, low BMI was associated with an increased risk of death (normal weight: HR 0.58, p=0.038; overweight/obese: HR 0.54, p=0.059). High BMI was not found to be a postoperative factor for poor prognosis in Japanese pancreatic cancer patients
Patient's Self-monitoring of Transurethral Surgical Images Using a Head-mounted Display
AbstractWe present an application of head-mounted display (HMD) to patient's self-monitoring of transurethral resection of bladder tumor (TURB). Six patients wore the HMD as an imaging monitor to view the operation in real-time during their TURB. Following the operation, the patients completed a questionnaire that evaluates understanding of the state of their disease and satisfaction with the HMD. As a result, monitoring the operation in real time through the HMD helped to increase patients' understanding of the state of their disease and satisfaction. For selected patients, the use of HMD could help to increase the patient's understanding of their disease
Changes in Antipsychotic Medication in Clients of Assertive Community Treatment in Japan: A One-Year Follow Up
The purpose of the present one-year follow-up study was to describe and investigate the change in the amount of antipsychotic drugs prescribed for ACT (assertive community treatment) clients in Japan. Subjects were 52 clients of ACT from January 2009 to December 2009. Prescription data were collected each month from the time the clients entered into ACT. The results of a Wilcoxon signed-rank test show that the dosage of antipsychotics significantly decreased from 1,131.3 mg to 731.3 mg over the course of the 12 months (Z = -2.505, p = 0.012)
Multiple rectal carcinoids with diffuse ganglioneuromatosis
BACKGROUND: Rectal carcinoids comprise only about 1% of all anorectal neoplasms. In addition, ganglioneuroma of the gastrointestinal tract is a rare tumor composed ganglion cells, nerve fibers, and supporting cells. Multiple carcinoid tumors with diffuse ganglioneuromatosis limited to the rectum are quite unusual. CASE PRESENTATION: A 69-year-old man was referred to us because of about 100 small submucosal rectal tumors. He underwent abdominoperineal resection. Pathology revealed carcinoid tumors for about 30 submucosal nodules and diffuse ganglioneuromotosis. To date (6 months later) he remains well with no recurrence. CONCLUSION: Although the optimal treatment for the multiple rectal carcinoids remains to be clearly established, it is believed that not all patients with multiple rectal carcinoids (measuring less than 1 cm in diameter) need to have a radical operation. However, the treatment plan for each case should be individualized and a careful follow-up is mandatory
Radiosynthesis and in vivo evaluation of two imidazopyridineacetamides, [11C]CB184 and [11C]CB190, as a PET tracer for 18 kDa translocator protein: direct comparison with [11C](R)-PK11195
Objective: We report synthesis of two carbon-11 labeled imidazopyridines TSPO ligands, [11C]CB184 and [11C]CB190, for PET imaging of inflammatory process along with neurodegeneration, ischemia or brain tumor. Biodistribution of these compounds was compared with that of [11C]CB148 and [11C](R)-PK11195. Methods: Both [11C]CB184 and [11C]CB190 having 11C-methoxyl group on an aromatic ring were readily prepared using [11C]methyl triflate. Biodistribution and metabolism of the compounds were examined with normal mice. An animal PET study using 6-hydroxydopamine treated rats as a model of neurodegeneration was pursued for proper estimation of feasibility of the radioligands to determine neuroinflammation process. Results: [11C]CB184 and [11C]CB190 were obtained via O-methylation of corresponding desmethyl precursor using [11C]methyl triflate in radiochemical yield of 73 % (decay-corrected). In vivo validation as a TSPO radioligand was carried out using normal mice and lesioned rats. In mice, [11C]CB184 showed more uptake and specific binding than [11C]CB190. Metabolism studies showed that 36 % and 25 % of radioactivity in plasma remained unchanged 30 min after intravenous injection of [11C]CB184 and [11C]CB190, respectively. In the PET study using rats, lesioned side of the brain showed significantly higher uptake than contralateral side after i.v. injection of either [11C]CB184 or [11C](R)-PK11195. Indirect Logan plot analysis revealed distribution volume ratio (DVR) between the two sides which might indicate lesion-related elevation of TSPO binding. The DVR was 1.15 ± 0.10 for [11C](R)-PK11195 and was 1.15 ± 0.09 for [11C]CB184. Conclusion: The sensitivity to detect neuroinflammation activity was similar for [11C]CB184 and [11C](R)-PK11195
Type I Angiotensin II Receptor Blockade Reduces Uremia-Induced Deterioration of Bone Material Properties
Chronic kidney disease (CKD) is associated with a high incidence of fractures. However, the pathophysiology of this disease is not fully understood, and limited therapeutic interventions are available. This study aimed to determine the impact of type 1 angiotensin II receptor blockade (AT-1RB) on preventing CKD-related fragility fractures and elucidate its pharmacological mechanisms. AT-1RB use was associated with a lower risk of hospitalization due to fractures in 3276 patients undergoing maintenance hemodialysis. In nephrectomized rats, administration of olmesartan suppressed osteocyte apoptosis, skeletal pentosidine accumulation, and apatite disorientation, and partially inhibited the progression of the bone elastic mechanical properties, while the bone mass was unchanged. Olmesartan suppressed angiotensin II-dependent oxidation stress and apoptosis in primary cultured osteocytes in vitro. In conclusion, angiotensin II-dependent intraskeletal oxidation stress deteriorated the bone elastic mechanical properties by promoting osteocyte apoptosis and pentosidine accumulation. Thus, AT-1RB contributes to the underlying pathogenesis of abnormal bone quality in the setting of CKD, possibly by oxidative stress. © 2020 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).Wakamatsu T., Iwasaki Y., Yamamoto S., et al. Type I Angiotensin II Receptor Blockade Reduces Uremia-Induced Deterioration of Bone Material Properties. Journal of Bone and Mineral Research, 36, 1, 67. https://doi.org/10.1002/jbmr.4159
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