Neutron Irradiation Effects in Al-Li and Al-Mg-Li Alloys

Al-2.3wt%Li and Al-4.1wt%Mg-1.1wt%Li alloys were neutron-irradiated in JOYO, JMTR and RTNS-II with different types of energy spectra. The changes of He production by different neutron sources and of precipitates due to the isothermal annealing at 400℃ were investigated by transmission electron microscopy (TEM). It was confirmed from TEM observations that He production by transmutation and the coagulation of He atoms after the annealing depend on neutron energy spectra used for the irradiation. It was also found that the addition of Mg to Al-Li alloy strongly suppresses the growth of He bubbles. Interrelations among precipitates, vacancies, He atoms and Li atoms were investigated, obtaining a reasonable coincidence between mutual amounts

Post mortem activation of human blood fibrinolytic enzyme in sudden and natural deaths

With the purpose to elucidate the cause and difference of blood fluidity in sudden death and natural one, we have observed the fibrinolysis of the blood in medico-legal and pathological autopsies by means of Fibrin Plate Method, a routine method devised in our laboratory. As the result it has been found that in the blood serum of sudden death and in some of natural deaths from tumors, leukemias, etc., the decrease in fibrinolytic activity is equivalent to the amount of proactivator that combined with the SK-like substance liberated into blood. On the other hand, in the blood of most of natural deaths, and in that bled from vessels and stored in body cavities, no natural fibrinolysis is observable and the same fibrinolytic activity with SK as normal one is demonstrated. Thus it is concluded that the cause of blood fluidity in sudden death is due to the fibrinolysis.</p

頭頸部領域および食道領域の各種症状に対する食道運動機能の関与について : High Resolution Manometry を用いた検討

頭頸部領域および食道領域における各種症状に対する食道運動機能の関与を検討した.2007年9月から2012年6月までに,咽喉頭異常感などの頭頸部領域の症状および嚥下困難感,胸痛,胸やけなどの食道領域に関連した症状を主訴に,当科を受診した261例(男性138例,女性123例,平均年齢56.8±17.1才)を対象とし,健康関連QOL(Health Related Quality of Life: HRQL)の測定と食道内圧検査を施行した.健康関連QOLの検討では,咽喉頭違和感,嚥下困難感,胸やけ等の各症状を訴えた患者で,身体的QOL,精神的QOL を表すPCS(physical component summary)あるいはMCS(mental component summary)が低下し,健常者と比較して有意にQOLの低下を認めた.食道内圧検査による食道運動機能異常は,全対象患者中62.0%に認めた.各症状別に食道運動機能障害の内訳を見ると,咽喉頭違和感ではIEM(ineffective esophageal motility)(31.8%),嚥下困難感は食道アカラシア(56.6%),喉のつかえ感は食道アカラシア(35.5%),胸やけはIEM(39.4%),胸痛は食道アカラシア(50.0%),噫気はIEM(50.0%)を最も多く認めた.咽喉頭違和感,嚥下困難感,喉のつかえ感,胸やけ,胸痛などの頭頚部および食道症状を有するものの,器質的疾患を認めない患者のQOLは障害されており,その病態の一つとして食道運動機能異常の存在を念頭に置き,診療にあたることが重要である.There are many cases of patients presenting at the hospital complaining of dysphagia or chest pain. At that time organic diseases are not always detected in these patients;previously several studies showed esophageal motility dysfunction was one of the important factors in the development of these symptoms. However, there have been few reports investigating the relationship between esophageal motility dysfunction and these symptoms. Between September 2007 and June 2012, 216 patients (138 men,123 women;mean age 56.8±17.1 years old) were admitted complaining of the following symptoms:dysphagia, globus sensation, or heart burn and non-cardiac chest pain,but without any organic diseases related symptoms. They all underwent high-resolution esophageal manometry (HRM) and completed a questionnaire regarding their health-related quality of life (HRQOL). The aim of this study was to evaluate the relationship between these symptoms and esophageal motility dysfunction and QOL. In our series, 62% of patients with non-obstructive dysphagia, globus sensation, heartburn and unexplained (non-cardiac) chest pain have an esophageal motility disorder (Achalasia 31.5%, IEM 26.4%, Diffuse esophageal spasm 4.6%;nutcracker esophagus 2.8% and Impaired ECJ relaxation 0.5%). SF-8 score of PCS(Physical Component Summary) in all of the symptoms were significantly lower in comparison with the matched healthy control. SF-8 score of MCS(Mental Component Summary) with globus sensation and esophageal dysphagia were significantly lower in comparison with the matched healthy control. The patients complaining of several symptoms located in the pharynx or esophagus have impaired quality of life and esophageal motility dysfunctions.It is important to consider these issues while examining these patients

体外式腹部超音波が診断に有用であった十二指腸巨大Brunner 腺過形成の一例

Brunner 腺過形成は十二指腸腫瘍性病変で，大きさが40mm を超えるものは10% 未満と稀である．医学中央雑誌で「腹部超音波」「Brunner 腺過形成」のキーワードで検索すると，関連した報告はない．体外式超音波検査（US）が診断に有用であったBrunner 腺過形成の一例を報告する．症例は50歳代，女性．食欲不振，心窩部痛とタール便を主訴に近医受診．貧血を認め，出血源検索目的に行った上部消化管内視鏡検査（EGD）で胃内に約 45 mm の腫瘤性病変を認め精査目的に当院紹介となった．血液生化学検査ではHb 9.1 g/dl，MCV 89.1 fl，MCH 30.0 pg と正球性正色素性貧血を認め，BUN/CRE 比は43.1と上昇していた．当院でのEGD では十二指腸球部に内腔をほぼ閉塞する45×40 mm の腫瘤性病変を認めた．腫瘤表面の異型性は目立たないが，oozing bleeding を伴ったびらん形成を認めた．粘膜下腫瘍を疑い生検も行われたが確定診断には至らなかった．単純造影CT では十二指腸球部に 45 mm 程度の腫瘤性病変を認め，辺縁は遷延性に造影された．内部は低吸収域が認められ，嚢胞変性や壊死が疑われた．周囲臓器への浸潤や転移を示唆する所見は認めず，粘膜下腫瘍が疑われたが癌は否定できなかった．US では十二指腸球部後壁の第２層から第３層に存在する約55 mm の粘膜下腫瘍が認められた．固有筋層は正常で，内部は大半が多房性嚢胞からなり，嚢胞間に充実成分がみられた．血流は比較的豊富であるが血管径や形状に明らかな不整は認めなかった．以上より十二指腸Brunner 腺過形成が疑われた．外科的切除の方針となり，開腹で十二指腸粘膜下層剥離術を行った．術材の組織診断はBrunner 腺過形成で超音波診断と矛盾しない所見であった．十二指腸粘膜下腫瘍の鑑別には超音波内視鏡が有用であるが，大きな病変では全体の描出が困難などの欠点もある．一方でUS は内視鏡侵襲なく，比較的大きな病変も描出可能で，特に本症例の様に前庭部付近は良好な観察が期待できるため，上部消化管の精査に応用できる．Brunner’s gland hyperplasia is a duodenal neoplastic lesion, and its lesions measuring >40 mm in diameter are rare, accounting for <10% of cases. A search of the Ichushi (Japana Centra Revuo Medicina) database using the keywords “abdominal ultrasound” and “Brunner’s gland hyperplasia” yielded no relevant articles. Here we report a case of Brunner’s gland hyperplasia in which transabdominal ultrasonography (US) was useful for diagnosis. A female in her 50s presented to a local hospital complaining of anorexia, epigastric pain and tarry stool. She had anemia and esophagogastroduodenoscopy (EGD), which was performed to identify the source of bleeding, revealed a mass lesion measuring approximately 45 mm in diameter in the stomach. She was referred to our hospital for further examination. Blood biochemistry showed a hemoglobin (Hb) level of 9.1 g/dL, mean corpuscular volume (MCV) of 89.1 fL and mean corpuscular hemoglobin (MCH) of 30.0 pg, indicating normocytic normochromic anemia. The blood urea nitrogen (BUN)/creatinine (CRE) ratio was as high as 43.1. In our hospital, EGD revealed a 45×40 mm mass lesion almost obstructing the lumen in the duodenal bulb. Atypia of the mass surface was not prominent, but erosion with oozing bleeding was observed. A submucosal tumor was suspected, and biopsy was performed but did not lead to a definitive diagnosis. Plain contrast-enhanced computed tomography (CT) revealed a mass lesion with prolonged peripheral enhancement measuring approximately 45 mm in diameter in the duodenal bulb. There was a low-density area inside the mass, raising the suspicion of cystic degeneration and necrosis. There were no findings suggesting infiltration or metastasis to the surrounding organs, raising the suspicion of a submucosal tumor, but cancer could not be ruled out. US revealed a submucosal tumor measuring approximately 55 mm in diameter in the second to third layer of the posterior wall of the duodenal bulb. The muscularis propria was normal and mostly composed of multilocular cysts with solid components in the space between the cysts. Blood flow was relatively abundant, but there were no obvious irregularities in the diameter or shape of blood vessels. The above findings raised the suspicion of duodenal Brunner’s gland hyperplasia. It was decided to perform surgical resection, and she underwent open duodenal submucosal dissection. Histology of the surgical specimen revealed Brunner’s gland hyperplasia, cons istent with the ultrasonographic findings. Endoscopic ultrasonography is useful in the differential diagnosis of duodenal submucosal tumors, but also has disadvantages such that it is difficult to visualize the entire lesion, when the lesion is large. On the other hand, US can be applied to the detailed examination of the upper gastrointestinal tract, because there are no invasive endoscopic procedures and US can visualize relatively large lesions and, in particular, can be expected to satisfactory observe around the vestibule, like in the present case

Direct Observation of Cu Clusters and Dislocation Loops by Cs-Corrected STEM in Fe-0.6wt%Cu Alloy Irradiated in BR2

The neutron irradiation of Fe-based fusion and fission reactor materials leads to an increase in ductile-to-brittle transition temperature with a decrease in upper shelf energy. It is well known that Cu content has a strong influence on the embrittlement phenomenon, as Cu-rich clusters (CRPs) are thought to be directly responsible for embrittlement. In contrast, mechanical property studies for steels with different Cu levels exhibit dominant matrix defects in the embrittlement of both low-Cu steels and high-Cu steels at high fluences. To determine the effects of dislocation loops and CRPs on radiation hardening in those steels, neutron irradiation was conducted on Fe-0.6wt%Cu alloy. The neutron irradiation was performed in BR2 at 290 °C up to a dose of 4.1 × 1024 n/m2. After irradiation, the microstructure was observed and analyzed by spherical aberration-corrected transmission electron microscopy (TEM) and scanning transmission electron microscopy (STEM) combined with X-ray energy-dispersive spectroscopy, using a JEOL ARM200FC. This technique enabled simultaneous observation of ~10 nm CRPs and dislocation loops. Additional high-voltage electron irradiation was performed at room temperature, and the dislocation loops were identified as interstitial-type dislocation loops. Radiation-induced hardening due to neutron irradiation was estimated by measuring the size and density of the dislocation loops and the CRPs. These results suggest that simultaneous observation of dislocation loops and CRPs using the Cs-corrected STEM with EDS analysis is essential for the study of radiation-induced hardening in Fe-based alloys