126 research outputs found
Magnetic field-induced one-magnon Raman scattering in the magnon Bose-Einstein condensation phase of TlCuCl
We report the observation of the -symmetric one-magnon Raman peak
in the magnon Bose-Einstein condensation phase of TlCuCl. Its Raman shift
traces the one-magnon energy at the magnetic point, and its intensity
is proportional to the squared transverse magnetization. The appearance of the
one-magnon Raman scattering originates from the exchange magnon Raman process
and reflects the change of the magnetic-state symmetry. Using the bond-operator
representation, we theoretically clarify the Raman selection rules, being
consistent with the experimental results.Comment: 6 pages, 4 figure
Evaluation of Myelotoxicity in Dietary Restricted Rats
The purpose of this study was to clarify the effect of decreased food consumption on evaluation of myelotoxicity in routine general toxicity studies. Male rats were divided into the following 7 groups: 12, 15, and 18 mg/kg 5-fluorouracil (5-FU) treatment groups (FU12, FU15 and FU18); dietary restriction groups (R12, R15 and R18 receiving the same amount of food as the rats in the FU12, FU15 and FU18 groups, respectively); and a nontreated control group (NT). We compared the changes in body weight, hematology and the results of cytological analyses of bone marrow and histopathology among the groups after administration and recovery periods of 14 and 7 days, respectively. At the end of the administration period, the FU15 and FU18 groups showed decreases in many hematologic and bone marrow parameters that were all similar to those in the corresponding dietary restriction groups (R15 and R18). A granulocyte abnormality (polyploidy: frequency of 1% or less) was also observed in all 5-FU treated groups. At the end of the recovery period, increases in the reticulocyte and platelet counts and extramedullary hematopoiesis of the spleen were observed in the 5-FU treated groups. These results indicate that the results of general toxicity studies in rats should be evaluated in consideration of dietary restriction effects when food consumption is decreased at about 30-40% or more. Careful morphological observation of hemocytes would be helpful in distinguishing the effect of a drug from that of dietary restriction in relation to hematological and bone marrow parameters. Performance of a recovery test to determine the reactive response of hematopoiesis is also recommended
Importance of Starting Age for Myelotoxicity Study in Dietary Restricted Rats
The aim of this study was to prove our hypothesis that adult rats with lowering of body weight gain, rats at 12 weeks of age as an example, are suitable for evaluation of myelotoxicity. Age-related differences between young rats (6-week-old study) and adult rats (12-week-old study) were analyzed in hematological examination values. The data of the young rats were reprinted from our previous report (Miyata et al., 2009) since our hypothesis was verified by comparison with that previous report. Several experimental groups were defined for the 12-week-old study as well as for the 6-week-old study; these included 5-fluorouracil (5-FU) treated groups receiving 12, 15 and 18 mg/kg/day (FU12, FU15 and FU18), pair-feeding groups (R12, R15 and R18 receiving the same amount of food as in the FU12, FU15 and FU18 groups, respectively) and a nontreated control group. Numerous hematologic and bone marrow parameters in the 5-FU treated groups were comparable to those in the corresponding pair-feeding groups in both age studies. Generally, the influences of undernutrition were more apparent in the young rats than in the adult rats. Histopathological examinations showed a decrease in hematopoiesis in the bone marrow in the 5-FU treated and pair-feeding groups. No apparent differences were observed in the decreased hematopoiesis between the 5-FU treated and pair-feeding groups in the 6-week-old study, but a difference between these groups was noted in the 12-week-old study; decreased hematopoiesis was more frequently noted in the 5-FU treated groups. These facts suggest that adult rats are more suitable than young rats for evaluation of 5-FU-induced myelotoxicity
Evaluation of Short-term Myelotoxicity Study in Dietary Reduced Rats
This study attempted to prove our hypothesis that a short-term toxicity study,
using a 4-day dosing regimen as an example, is suitable for evaluating
myelotoxicity in rats. We compared the hematological, bone marrow cytological
and histopathological results of 5-fluorouracil (5-FU) treated and pair-feeding
groups after a 4-day administration period. Several experimental groups were
defined for this 4-day study as well as for our previously reported 14-day study
(Miyata et al., 2009); these included 5-FU treated groups
receiving 12, 15 and 18 mg/kg/day (FU12, FU15 and FU18), pair-feeding groups
(R12, R15 and R18 receiving the same amount of food as the FU12, FU15 and FU18
groups, respectively) and a nontreated control group. Although severe reductions
in body weight gain and food consumption were reported in the 14-day study, only
slight reductions were observed in the 4-day study. In the 4-day study, a
decrease in blood reticulocytes and a decreasing trend of marrow erythroid cells
were only observed in the FU18 group, and no effects were observed in the
pair-feeding groups. The erythroblastic changes observed in this 4-day study
were thought to reflect the direct influence of 5-FU administration. Since
concerns regarding the influence of secondary changes related to undernutrition
were minimized in the 4-day study, it was thought to clarify the direct
influence of 5-FU administration on erythroblastic cells. Thus, a 4-day study
protocol might be helpful for distinguishing secondary changes related to
undernutrition
血中の2,3,4,7,8-五塩化ダイベンゾフラン(PeCDF)の個人の半減期:油症患者における臨床症状並びに検診結果との関係
BACKGROUND:
In 1968, many people developed dioxin poisoning (Yusho) in Japan. Ingestion of 2,3,4,7,8-pentachlorodibenzofuran (2,3,4,7,8-PeCDF) was considered to be the cause of this poisoning. Although some patients had high concentrations of 2,3,4,7,8-PeCDF in their blood, individuals' half-lives of 2,3,4,7,8-PeCDF were long.
OBJECTIVES:
To evaluate the relationship between clinical and laboratory parameters and the individual half-life of 2,3,4,7,8-PeCDF in blood.
METHODS:
Clinical and laboratory data were collected during annual check-ups from 2001 to 2008. We enrolled 71 patients, who were measured more than 3 times, and who had 2,3,4,7,8-PeCDF concentrations in blood >50pgg(-1) lipid. The half-life of 2,3,4,7,8-PeCDF for each patient was estimated using linear regression. Moreover, relationships between clinical and laboratory parameters and individual half-life were investigated by linear regression.
RESULTS:
A shortened individual half-life for 2,3,4,7,8-PeCDF was significantly correlated with an increased red blood cell count, increased viscous secretions from the meibomian glands, existing black comedones, and severe cedar pollen allergy.
CONCLUSIONS:
Symptoms that accelerate excretion of lipids from the body, such as viscous secretions from the meibomian glands, may lead to a shorter half-life of 2,3,4,7,8-PeCDF. Red blood cells are related to the half-life of 2,3,4,7,8-PeCDF. However, further studies are required to investigate the excretory mechanism of 2,3,4,7,8-PeCDF.博士(医学)・乙1325号・平成26年3月17
Development of Exchange Activities with the International Students for Nurturing Global Human Resources: Focusing on Communication Skills, Cooperativity and Flexibility
This research project developed and practiced some exchange activities with international university students to nurture global human resources at the kindergarten level. The project was constructed with four strategic approaches to focus on developing communication skills, cooperativity and flexibility in children. The studies concluded that children's amical feeling toward international students have acted as a springboard to seek active interaction and to provide support when needed. Developmental level of children should also be considered to promote communication and flexibility. Further research on flexibility is necessary both in literature and in practice
Impact of a learning health system on acute care and medical complications after intracerebral hemorrhage
Introduction: Patients with stroke often experience pneumonia during the acute stage after stroke onset. Oral care may be effective in reducing the risk of stroke‐associated pneumonia (SAP). We aimed to determine the changes in oral care, as well as the incidence of SAP, in patients with intracerebral hemorrhage, following implementation of a learning health system in our hospital.
Methods: We retrospectively analyzed the data of 1716 patients with intracerebral hemorrhage who were hospitalized at a single stroke center in Japan between January 2012 and December 2018. Data were stratified on the basis of three periods of evolving oral care: period A, during which conventional, empirically driven oral care was provided (n = 725); period B, during which standardized oral care was introduced, with SAP prophylaxis based on known risk factors (n = 469); and period C, during which oral care was risk‐appropriate based on learning health system data (n = 522). Logistic regression analysis was performed to evaluate associations between each of the three treatment approaches and the risk of SAP.
Results: Among the included patients, the mean age was 71.3 ± 13.6 years; 52.6% of patients were men. During the course of each period, the frequency of oral care within 24 hours of admission increased (P < .001), as did the adherence rate to oral care ≥3 times per day (P < .001). After adjustment for confounding factors, a change in the risk of SAP was not observed in period B; however, the risk significantly decreased in period C (odds ratio 0.61; 95% confidence interval 0.43‐0.87) compared with period A. These associations were maintained for SAP diagnosed using strict clinical criteria or after exclusion of 174 patients who underwent neurosurgical treatment.
Conclusions: Risk‐appropriate care informed by the use of learning health system data could improve care and potentially reduce the risk of SAP in patients with intracerebral hemorrhage in the acute stage
Biphasic Aire expression in early embryos and in medullary thymic epithelial cells before end-stage terminal differentiation
The roles of autoimmune regulator (Aire)–expressing medullary thymic epithelial cells (mTECs) in the organization of the thymic microenvironment for establishing self-tolerance are enigmatic. We sought to monitor the production and maintenance of Aire-expressing mTECs by a fate-mapping strategy in which bacterial artificial chromosome transgenic (Tg) mice expressing Cre recombinase under the control of the Aire regulatory element were crossed with a GFP reporter strain. We found that, in addition to its well recognized expression within mature mTECs, Aire was expressed in the early embryo before emergence of the three germ cell layers. This observation may help to explain the development of ectodermal dystrophy often seen in patients with AIRE deficiency. With the use of one Tg line in which Cre recombinase expression was confined to mTECs, we found that Aire+CD80high mTECs further progressed to an Aire−CD80intermediate stage, suggesting that Aire expression is not constitutive from after its induction until cell death but instead is down-regulated at the beginning of terminal differentiation. We also demonstrated that many mTECs of Aire-expressing lineage are in close contact with thymic dendritic cells. This close proximity may contribute to transfer of tissue-restricted self-antigens expressed by mTECs to professional antigen-presenting cells
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