Long-term stability of beam quality and output of conventional X-ray units

Conventional diagnostic X-ray units are used for radiographic imaging in many countries. For obtaining entrance surface doses, a numerical dose determination method has been applied in Japan. Although this technique is effective, it has to account for errors, particularly fluctuations, due to the beam quality and output of X-ray tubes. As a part of our quality control procedures, we recorded the entrance surface air kerma, tube voltage, and half-value layer measurements made for four diagnostic X-ray tubes over a 103-week period. The entrance surface air kerma for one of the four X-ray tubes had increased significantly by 11.4 % over 1 year from its initial setting, whereas the tube voltages and half-value layers did not deviate significantly from their initial values. Medical physicists and radiological technologists should be aware of this fluctuation for diagnostic X-ray tubes and take it into consideration when calculating the entrance surface air kerma. © 2014 Japanese Society of Radiological Technology and Japan Society of Medical Physics.発行後1年より全文公

Co-morbidity of progressive supranuclear palsy and amyotrophic lateral sclerosis : a clinical-pathological case report

Background: The coexistence of distinct neurodegenerative diseases in single cases has recently attracted greater attention. The phenotypic co-occurrence of progressive supranuclear palsy (PSP) and amyotrophic lateral sclerosis (ALS) has been documented in several cases. That said, the clinicopathological comorbidity of these two diseases has not been demonstrated. Case presentation: A 77-year-old man presented with gait disturbance for 2 years, consistent with PSP with progressive gait freezing. At 79 years old, he developed muscle weakness compatible with ALS. The disease duration was 5 years after the onset of PSP and 5months after the onset of ALS. Neuropathological findings demonstrated the coexistence of PSP and ALS. Immunohistochemical examination confirmed 4-repeat tauopathy, including globose-type neurofibrillary tangles, tufted astrocytes, and oligodendroglial coiled bodies as well as TAR DNA-binding protein 43 kDa pathology in association with upper and lower motor neuron degeneration. Immunoblotting showed hyperphosphorylated full-length 4-repeat tau bands (64 and 68 kDa) and C-terminal fragments (33 kDa), supporting the diagnosis of PSP and excluding other parkinsonian disorders, such as corticobasal degeneration. Genetic studies showed no abnormalities in genes currently known to be related to ALS or PSP. Conclusions: Our case demonstrates the clinicopathological comorbidity of PSP and ALS in a sporadic patient. The possibility of multiple proteinopathies should be considered when distinct symptoms develop during the disease course

Qualitative investigation of the factors that generate ambivalent feelings in women who give birth after receiving negative results from non-invasive prenatal testing

Background: Women who receive negative results from non-invasive prenatal genetic testing (NIPT) may find that they later have mixed or ambivalent feelings, for example, feelings of accepting NIPT and regretting undergoing the test. This study aimed to investigate the factors generating ambivalent feelings among women who gave birth after having received negative results from NIPT. Methods: A questionnaire was sent to women who received a negative NIPT result, and a contents analysis was conducted focusing on ambivalent expressions for those 1562 women who responded the questionnaire. The qualitative data gathered from the questionnaire were analyzed using the N-Vivo software package. Results: Environmental factors, genetic counseling-related factors, and increased anticipatory anxiety, affected the feeling of ambivalence among pregnant women. Furthermore, pregnant women desired more information regarding the detailed prognosis for individuals with Down syndrome and living with them and/or termination, assuming the possibility that they were positive. Conclusions: Three major interrelated factors affected the feeling of ambivalence in women. Highlighting and discussing such factors during genetic counseling may resolve some of these ambivalences, thereby enhancing the quality of decisions made by pregnant women

枝打ち機械を使用する作業の強度(B. 生活科学)

3人の林業労働者について, 枝打ち機械を使用した作業中の心拍数を連続測定し, 同時にステップテストによって心拍数とエネルギー消費量等の関係を測定して作業の強度を求めた。1人1台, 2人3台, 1人2台の機械使用作業それぞれについて, 最大酸素摂取量に対する酸素摂取量の割合は44.2±8.9%, 52.9±9.5%, 62.3±11.4%, エネルギー消費量は5.09±1.23kcal/kg/h, 6.20±1.32kcal/kg/h, 7.36±1.61kcal/kg/h, RMRは4.0±1.3,5.0±1.3,6.2±1.7であった。1人で1台の枝打ち機械を使用した場合の作業強度は手作業より低く, 2人3台で手作業とほぼ等しく, 1人2台では手作業より高く, 無酸素性作業閾値付近を前後する激しい労働であった。枝打ち機械を改良して上昇速度を速くすれば作業功程が改善されるが。労働強度が増加するので, 同時に機械の軽量化が必要である。枝打ち作業に従事すれば, 機械を使用した作業でも手作業でも, その生活は, 第三次改定日本人の栄養所要量による生活活動の強度4段階のうち一番強度の高い, IV(重い)に位置づけられる。Work intensity of 3 forest workers during work with pruning machines were measured with portable heart rate recorders continuously under 3 levels of work load, i. e. 1 machine per 1 person, 3 machines per 2 persons and 2 machines per 1 person. To assess work rate from heart rate response, relationships between heart rate and 0_2 uptake and energy expenditure were measured simultaneously applying a step test on each subject. Then work intensity of each subject was estimated from the relationship between heart rate and 0_2 uptake. The work intensities observed during 1 machine per 1 person, 3 machines per 2 persons and 2 machines per 1 person, were 44.2±8.9,52.9±9.5 and 62.3±11.4% of VO_2 max, respectively. Energy expenditures of those groups were 5.09±1.23,6.20±1.32 and 7.36±1.61 kcal/kg/h, and those of RMR were 4.0±1.3,5.0±1.3 and 6.2±1.7. The work intensity of forest workers engaging in pruning work, both with machines and manually, corresponds to IV (heavy) in the Japanese Recomended Dietary Allowances, i. e. grade of the most highest class