現像温度および時間のマンモフイルム特性に与える影響

The influence for developing temperature and processing time within film processing conditions was investigated using four mammographic films, Konica New CM, Fuji UM-MA HC, Kodak Min-R M and Kodak EB/RA (for rapid system). And Fuji UR-2, a double-emulsion film, was used as a control. Those sensitometric strips exposed by a sensitometer were processed in the different combinations of developing temperatures ranging from 28 to 36℃, processing times from 45 to 210 sec. Average gradient, relative speed and base plus fog obtained from the measured film characteristic curves were evaluated for the different developing temperatures and times. Fuji UR-2 was scarcely affected and mammographic films were greatly affected in the different combinations without an increase in base plus fog except EB/RA. In New CM, UM-MA HC and Min-R M, the average gradients and the relative speeds increased as the developing temperature was higher and the developing time was longer, but the increases were limit on the combination of 36℃ and 210 sec in New CM and UM-MA HC. In EB/RA, the average gradients were almost constant and the relative speeds increased slightly like the double-emulsion film. These results suggested that it would be possible to contribute to dose reduction and advancement of contrast in New CM, UM-MA HC and Min-R M by changing these processing parameters.フィルム処理条件において,現像温度と処理時間に対する影響を4種類のマンモグラフィ用フィルムKonica New CM, Fuji UM-MA HC,Kodak Min-R M,迅速処理用Kodak EB/RAについて調べた｡そして,比較基準用として両面乳剤フィルムFuji UR-2を用いた｡感光計で露光したフィルムを現像温度28～36℃,処理時間45～210秒で処理した｡特性曲線から得られたフィルム特性（平均階調度,相対感度,カブリ濃度）を異なる現像温度,現像時間に対して評価した｡UR-2はほとんど影響を受けず,マンモグラフィ用フィルムは,カブリ濃度が上昇することなく,現像条件の影響を大きく受けた。New CM, UM-MA HC,Min-R Mは現像温度の上昇,処理時間の延長に伴い,平均階調度と相対感度は増加した｡しかし,New CM, UM-MA HCの36℃,210秒で増加は限度に達した｡EB/RAの平均階調度は一定で,相対感度は両面乳剤フイルムと同 様にわずかな増加であった｡これらの結果は,New CM, UM-MA HC, Min-R Mにおいて,処理条件を変化させることにより,被曝低減,コントラスト向上に貢献できる可能性を示唆していた

[11C]Doxepin binding to histamine H1 receptors in living human brain: reproducibility during attentive waking and circadian rhythm

Molecular imaging in neuroscience is a new research field that enables visualization of the impact of molecular events on brain structure and function in humans. While magnetic resonance-based imaging techniques can provide complex information at the level of system, positron emission tomography (PET) enables determination of the distribution and density of receptor and enzyme in the human brain. Previous studies using [11C]raclopride and [11C]FLB457 revealed that the release of neuronal dopamine was increased in human brain by psychostimulants or reward stimuli. Following on from these previous [11C]raclopride studies, we examined whether the levels of neuronal release of histamine might change [11C]doxepin binding to the H1 receptors under the influence of physiological stimuli. The purpose of the present study was to evaluate the test–retest reliability of quantitative measurement of [11C]doxepin binding between morning and afternoon and between resting and attentive waking conditions in healthy human subjects. There was a trend for a decrease in [11C]doxepin binding during attentive calculation tasks compared with that in resting conditions, but the difference (less than 10%) was not significant. Similarly, the binding potential of [11C]doxepin in the cerebral cortex was slightly higher in the morning than that in the afternoon, but it was also insignificant. These data suggest that higher histamine release during wakefulness could not decrease the [11C]doxepin binding in the brain. This study confirmed the reproducibility and reliability of [11C]doxepin in the previous imaging studies to measure the H1 receptor

The influence of air attenuation in characteristic curve for mammographic screen-film system

マンモグラフィ専用装置を使用して，距離法で低エネルギー領域のX線におけるマンモグラフィ用増感紙／フィルムシステムの特性曲線を得るためには，空気滅弱の影響を考慮する必要がある。その影響について，実効エネルギーから空気減弱分を補正，照射線量測定による補正，Bednarek法を応用した新距離法の3種類の方法を使って検討した。さらに，一般撮影装置でも，マンモ用システムに対して距離法で特性曲線を作成し，エネルギ ーの変化による影響についても検討した。その結果，3方法の特性曲線およびグラディエント曲線は，新距離法が高濃度域でわずかにずれるもののほぼ一致した。新距離法に対する平均階調度，最大階調度の最大誤差は，2.7％，0.2％であり，一般撮影用装置の距離法と3方法との間では，一般撮影用装置の距離法に対して最大誤差は2.7％，1.5％であった。以上のことから，エネルギーの変化による特性曲線への影響はほとんどなく，低エネルギー領域での特性曲線は空気特配の補正を行うことのみで得られると考えられる。It is necessary to take air attenuation into account when we use inverse square sensitometry to obtain characteristic curve for the mammographic screen-film system at low x-ray energies as used with the dedicated unit. Three kinds of the inverse square sensitometry approach of correcting by air attenuation obtained from effective energy, of correcting by exposure dosimetry and of using modified the technique of Bednarek were employed to investigated the influence of x-ray energy in the characteristic curves for the mammographic screen-film system. In addition, the inverse square sensitometry with the general radiographic unit was employed and the influence of x-ray high energy in the characteristic curves was also investigated for the same screeri-film system. Though characteristic curves and gradient curves of the new inverse square sensitometry were a little lower than the others in high-density region, the curves with three kinds of methods almost coincided. Maximum relative errors of average gradient and maximum gradient for modified the technique of Bednarek were found to be 2.7% and 0.2% among the others respectively. Moreover, maximum relative errors of gradient and maximum gradient for the inverse square sensitometry with the general radiographic unit were 2.7% and 1.5% among three kinds of methods with the dedicated unit respectively. It was considered that the characteristic curves for the mammographic screen-film　system were little influenced by x-ray energy and could be obtained only by correcting　air attenuation from above results

Estimation of balium preparations with high density and low viscosity

In this paper we compared the balium preparations having high density and low viscosity (BP-HDLV) with those currently in use. We adopted the stomaches of pigs and the new phantom manufactured by ourselves. We especialy noted the quality of the contrast. The results indicate that BP-HDLV do not always make high contrast. The contrast is related to fluidity besides density. The fluidity of BP-HDLV should be improved. In adition, it costs much to increase content of balium. Therefore, we can not find out positive significance to use these BP-HDLV

Gene Expression Analysis of a Murine Model with Pulmonary Vascular Remodeling Compared to End-Stage IPAH Lungs

BACKGROUND: Idiopathic pulmonary arterial hypertension (IPAH) continues to be one of the most serious intractable diseases that might start with activation of several triggers representing the genetic susceptibility of a patient. To elucidate what essentially contributes to the onset and progression of IPAH, we investigated factors playing an important role in IPAH by searching discrepant or controversial expression patterns between our murine model and those previously published for human IPAH. We employed the mouse model, which induced muscularization of pulmonary artery leading to hypertension by repeated intratracheal injection of Stachybotrys chartarum, a member of nonpathogenic and ubiquitous fungus in our envelopment. METHODS: Microarray assays with ontology and pathway analyses were performed with the lungs of mice. A comparison was made of the expression patterns of biological pathways between our model and those published for IPAH. RESULTS: Some pathways in our model showed the same expression patterns in IPAH, which included bone morphogenetic protein (BMP) signaling with down-regulation of BMP receptor type 2, activin-like kinase type 1, and endoglin. On the other hand, both Wnt/planar cell polarity (PCP) signaling and its downstream Rho/ROCK signaling were found alone to be activated in IPAH and not in our model. CONCLUSIONS: Activation of Wnt/PCP signaling, in upstream positions of the pathway, found alone in lungs from end stage IPAH may play essential roles in the pathogenesis of the disease

A study on the scattering exposure dose in radiotherapy.

現代の医療のなかで癌治療において不可欠な存在となった放射線治療｡一方,放射線被曝はたとえわずかであってもリスクが伴い,厳しく規制されている｡ただし医療被曝はこの限りになく,過去においては癌患者に放射線治療をおこなう際の患部以外の被曝についてはあまり問題視されなかった｡これには癌の治療という前提に加え,長期生存の可能性が低く,存命中に晩発障害が発生することが低いと考えられていたからである｡しかし,集学的治療が確立した今後の放射線治療においては完治する放射線治療患者が多くなり,治癒後の余命が長くなることが予測される｡放射線被曝による確率的影響は閾値がなく,影響は当然現れるであろう｡そこで,放射線治療をおこなう際の患者の散乱線被曝線量,治療室内散乱線量,さらに高エネルギー放射線発生装置を取り扱うときに問題となっている中性子を測定した｡その結果,測定線量は治療患部外被曝,室内散乱線量ともに無視できない量であることがわかった｡中性子については,人体に影響がある線量は検出されなかったが,中性子の存在は室内物品の放射化の可能性を示唆するもので定期的な測定管理が必要である｡また,Ⅹ線撮影室用の防護衣による散乱線被曝の低減効果は放射線治療室では無意味であった｡In modern medicine, radiotherapy has proved indispensable in the treatment of cancer. However. radiation exposure is a health hazard. and is thus strictly regulated. In the past, incidental exposure was not considered to pose a considerable risk, and because radiotherapy was an effective treatment for cancer and because the possibility of the long-term survival was generally poor, the prevalence of radiation injury was thought to be low. In recent years, however, more patients are making complete recoveries, and it is believed that long-term survival is possible with future radiotherapy techniques. There is no threshold for the stochastic effects of radiation exposure, and thus such effects may be detected even at low levels. In the present study, we measured the radiation exposure due to scattered rays from the patient, incidental radiation levels in the radiotherapy room, and levels of neutron radiation. which is a problem when high-energy X-ray radiotherapy systems are used. The results showed that exposure due to scattered rays and incidental levels in the radiotherapy room cannot be dismissed. and that further investigation is warranted. As for neutron radiation, dosages were below those that are known to influence the human body, but regular measurement is necessary because it may induce radioactivity in otherwise benign equipment. In addition, a protective apron had no effect on the exposure due to scattered rays in the radiotherapy room

The contrast media containing soft drinks for X-ray examination of the stomach

胃検診の受診者を増やし、検査を円滑に行う上で、造影剤である硫酸バリウム懸濁液の飲みにくさが障害の一つとなっている。これを改善する試みとして、懸濁液に市販の粉末清涼飲料を混入し検討したところ72.1％の人から通常のものよりも飲みやすいという回答を得た。今後、臨床的な検討を加えながら、さらに創意工夫していく必要がある。Barium sulfate suspensions are disliked to drink by many people. That is one of the obstacles to increse person who consult doctors and to have medical examinations smoothly. We mixed soft drinks into the suspensions to improve this problem. As a result they were popular among 72.1% people. We need to study about these suspensions further, adding the clinical matters

Physical Properties of Screen-Film Systems - New System for Chest Radiography -

胸部専用の新しい増感紙／フィルムシステムについて物理的画質特性を測定し、従来のシステムと比較を行った。測定した新システムは、日本コダックのインサイトシステムからHC/IT-1、富士メディカルシステムのADシステムからHG-M/UR-1、コニカのEXシステムからXG-S/ES-C である。従来のシステムとして富士メディカルシステムのHR-4/Super HR-S を使用した。その結果、新システムは22～73％感度は高く、特性曲線においては低濃度部を持ち上げ、最大コントラストは高濃度側にシフトしていた。空間周波数2cycles/mmで相対鮮鋭度を比較すると、新システムが10～30％程度の低下となっていた。ノイズは、濃度1.0で新システムが35～46％の減少となった。以上より、新システムは、縦隔部の濃度を上げ、粒状性の改善を重視した設計となっていることが分かった。The new three screen-film systems, Kodack INSIGHT system HC/IT-1, Fuji AD system HG-M/UR-1, and Konica EX system XG-S/ES-C for chest radiography were evaluated. In addition, the conventional system Fuji HR-4/Super HR-S was measured for comparison with new systems. The evaluation method is as follows. The image quality characteristics, speed, contrast, resolution and granularity were measured. The sensitivity and contrast were determined by measuring the MTF (modulation transfer function) and NCTF (normalized contrast transfer function). The granularity was estimated by measuring the Wiener spectrum. The speed of the new systems were improved by 22% to 73%. The dinsities at the maximum gradient value were shifted to high density (2.0-2.7). However, they had 10% to 30% less resolution. The other hand, the granularities were improved by 21% to 37% at 1.0 density. These results suggested that the emphasis of new systems was put on improving the image quality of mediastinum region, maintaining performance of the conventional system

Analysis of Tempormandibular Joint by Image Processing -Discrimination of Condylar Position-

Tomography is clinically useful in the diagnosis of the temporomandibular joint (TMJ) syndrome. The TMJ is formed by the condyle and the glenoid fossa, and there exists TMJ space between them. Image processing was employed in the present study, and the reference points of the condyle and the glenoid fossa were determined from the tomogram. Subsequently, the TMJ space was measured automatically in the image analysis. The TMJs of 98 patients were examined practically and the characteristics of each result were studied. There is a possibility of discriminating an abnormal condylar position from a normal one by making use of the TMJ space and the distance between two reference points

Clinical evaluation of barium sulfate suspensions "Barytgen HD" - Second report -

混合粒子型硫酸バリウム｢バリトゲンHD｣の懸濁液最適濃度について,検討を行った｡懸濁液安定性は,200w/v%と190w/v%は良好であったが,180w/v%は不良で臨床使用には不向きであると思われた｡臨床的評価において200w/v%と190w/v%は付着性,辺縁の描出能,胃小区描出能においては同程度であった｡200w/v%に多く見られた凝集･ムラ付き,気泡は,190w/v%では少なくなった｡飲み易さは,200w/v%,190w/v%とも飲み易いと評価されたが,190w/v%でより飲み易い傾向にあった｡バリトゲンHDの最適懸濁液濃度は,190w/v%であると思われる｡Barium sulfate suspensions in 200w/v% and 190w/v% had good stability. But in 180w/v% it had worse stability. Significant difference was not observed in coating, visualization of gastric margin and gastric area between in 200w/v% and 190w/v%. Barium sulfate suspensions in 190w/v% had less sticky coating of gastric mucosa and fewer bubbles than 200w/v%. Barium sulfate suspensions in 190w/v% was easiest density to drink. 190w/v% seems to be most adequate density in our study