Identifying Suspicious Regions of Covid-19 by Abnormality-Sensitive Activation Mapping

This paper presents a fully-automated method for the identification of suspicious regions of a coronavirus disease (COVID-19) on chest CT volumes. One major role of chest CT scanning in COVID-19 diagnoses is identification of an inflammation particular to the disease. This task is generally performed by radiologists through an interpretation of the CT volumes, however, because of the heavy workload, an automatic analysis method using a computer is desired. Most computer-aided diagnosis studies have addressed only a portion of the elements necessary for the identification. In this work, we realize the identification method through a classification task by using a 2.5-dimensional CNN with three-dimensional attention mechanisms. We visualize the suspicious regions by applying a backpropagation based on positive gradients to attention-weighted features. We perform experiments on an in-house dataset and two public datasets to reveal the generalization ability of the proposed method. The proposed architecture achieved AUCs of over 0.900 for all the datasets, and mean sensitivity $0.853 \pm 0.036$ and specificity $0.870 \pm 0.040$. The method can also identify notable lesions pointed out in the radiology report as suspicious regions.Comment: 10 pages, 3 figure

A case of gastrointestinal stromal tumor (GIST) with peritoneal dissemination : Imatinib re-challenged case

Unresectable, metastatic, recurrent gastrointestinal stromal tumor (GIST) is primarily treated with a molecular-targeted therapeutic agent, imatinib. However, after an initial response, a secondary resistance to the drug often occurs after a few years. We report here a case of a resected giant GIST of the jejunum that disseminated following treatment with imatinib. A 59-year-old male presented with a giant tumor in the abdominal cavity, which was diagnosed as GIST by needle biopsy; he was administered 400 mg/day imatinib. Eight months later, the tumor had considerably decreased, but multiple tumors in small intestine and mesenterium, indicating dissemination, appeared. Administration of imatinib was continued for 36 months from the initial treatment and the dissemination gradually reduced and almost disappeared except for a tumor in the right upper abdomen. Three years later, follow-up computed tomography revealed that the disseminated lesions had enlarged; a part of the intrapelvic tumor was suspected to be viable. We deduced that the tumor developed partial resistance to imatinib: therefore, we surgically removed as many disseminated tumors as possible. Pathologically, resected tumors appeared to have no viable tumor cells except for a small part of the primary tumor in which mitosis was 0-1/50 high-power fields. Genetic analysis of surgically resected specimen for c-kit mutation revealed an exon 11 c554-559 deletion. 17 months after operation, another disseminated tumor was detected. Imaninib therapy was re-introduced. The dissemination was diminished after three months re-challenged imatinib and continues to be recurrence-free for two years. When partial resistance to imatinib is observed, combined modality therapy that involves chemotherapy with surgical intervention at early stages is expected to improve the outcome

Arginine enriched EN after total gastrectomy

The effects of early enteral arginine-rich nutrition (EAN) were analyzed among patients undergoing curative-intent total gastrectomy for gastric cancer. There were 19 patients in this prospective study, all randomly assigned to either a parenteral nutrition (PN) group or an EAN group for the first seven days after surgery. The EAN group received 1.8-fold greater arginine (10.1 g / day) compared with the PN group, which was administered through an enteral tube inserted into the jejunal loop. Both groups were provided almost identical amounts of total amino acids (54 g / day), and the total energy was set at 65% of the total requirement (25 kcal / kg / day). No significant differences were observed between the two groups in postoperative complications, length of hospital stay, oral intake, nutritional status, or body weight. The serum arginine profile was similar in the two groups, as it decreased significantly on postoperative day (POD) 1, and gradually returned to preoperative levels by POD 7. The nitrogen balance remained negative until POD 7 in the PN group, but turned neutral at POD 7 in the EAN group. While we could not confirm body weight loss improvement, these results suggested that early arginine-rich enteral nutrition could improve the nitrogen balance after total gastrectomy

日本脳炎ウイルスの生態学的研究.1968年の調査成績

A serial survey on the ecology of Japanese encephalitis (JE) virus was made in 1968. Virus isolation was negative from 848 hibernated females of Culex tritaeniorhynchus collected in March to early May. In mid May, when newly emerged females appeared, and thereafter, attempts to isolate the virus were continued, but it was July 23 that the first isolation was made. A strain of JE virus was isolated each from C. pseudovishnui in early August and from Aedes vexans nipponii in late July. Eight other species of mosquitoes were negative for JE virus throughout the year. The pigs susceptible to JE virus were exposed in nature to mosquitoes including hibernated females of C. tritaeniorhynchus in spring without detecting the rise in hemagglutination inhibition (HI) antibody in their sera. Continuing the exposure to mosquitoes, the HI antibody was detected only after early August. The number of human cases was smaller than in any of the previous three years. One of the reasons is considered to be that the number of vector mosquitoes was smaller at the time of the epizootic in pigs.前年までに引き続き,1968年に日本脳炎ウイルスの生態学的調査を行なった.3月-5月上旬に採集したコガタアカイエカ越冬雌成虫848個体からはウイルスは分離されなかった.新生雌成虫が出現し始めた5月中旬及びそれ以後も分離を試みたが,始めて日本脳炎ウイルスが分離できたのは7月23日であった.シロハシイエカからは8月上旬に,キンイロヤプカからは7月下旬に,各々1株の日本脳炎ウイルスが分離された.感受性の豚を各々1頭ずつ2月下旬に3部落の豚舎に配って,自然に蚊から吸血されるままにして飼育し続けて,HI抗体が出現する時期を調べたが,抗体が検出されたのは8月上旬以降であった.発生患者数は,過去3年の何れにおけるよりも少なかった.その理由の1つは,豚で日本脳炎の流行が起っている時期のコガタアカイエカの数が少なかったことであると考えられる

日本脳炎ウイルスの生態学の研究 : 1969年,1970年及び1971年の調査成績

Serial surveys on the ecology of Japanese encephalitis virus in Nagasaki area were made during from 1969 to 1971. In total, 11,229 hibernated female mosquitoes of Culex tritaeniorhynchus were caught in early spring every year for virus isolation, however it was unsuccessful. The significant increase of hemagglutination inhibition antibody possessing rate in the sera of slaughtered pigs in early spring was not found in these three years. Virus isolations from the vector mosquitoes in epidemic season were made from 1st to 26th of August in 1969, from 19th of July to 16th of August in 1970 and from 13th to 27th of July in 1971, respectively. Although the isolation efficiencies were not remarkably different at the highest level in a certain limited period in epidemic season during the years 1964 to 1971, the periods for JE virus isolation from the vector mosquitoes became shorter in the years from 1968 to 1971 than from 1964 to 1967. It was considered as one of the reasons that the number of the vector mosquitoes was smaller during the epizootic from 1968 to 1971 than from 1964 to 1967. Subsequently, it was noted that the encephalitis case sbecame to decrease in number in recent years.1969年,1970年及び1971年の3年間に越年コガタアカイエカ11,229個体,65プールについて哺乳マウス脳内接種法でウイルスの分離を試みたが,成績は陰性であった.流行期における蚊からのウイルスの分離は1969年は,8月1日から8月26日まで,1970年は,7月19日から8月6日まで,1971年は7月13日から7月27日までの期間であった.各年の捕集蚊からの日脳ウイルスの分離効率は最も高いときは1969年3.6,1970年4.8,1971年4.4であって,1968年以前の流行盛期のそれと大差がない.以上の事実は,最近3年間の野外でのコガタアカイエカのウイルス汚染が流行期の或る一時期には1968年以前と同じくらいに行われていることを示している.これに反して,蚊からのウイルスの分離期間が異常に短かくなっていることは,コガタアカイエカの発生,消長が最近3年間では著しく減少していることに,その一つの要因を求めることが出来る.これと平行して.患者数も減少し,1969年19名,1970年17名,1971年3名の届出患者があったにすぎない

Predicting disease progression from short biomarker series using expert advice algorithm

Well-trained clinicians may be able to provide diagnosis and prognosis from very short biomarker series using information and experience gained from previous patients. Although mathematical methods can potentially help clinicians to predict the progression of diseases, there is no method so far that estimates the patient state from very short time-series of a biomarker for making diagnosis and/or prognosis by employing the information of previous patients. Here, we propose a mathematical framework for integrating other patients' datasets to infer and predict the state of the disease in the current patient based on their short history. We extend a machine-learning framework of "prediction with expert advice" to deal with unstable dynamics. We construct this mathematical framework by combining expert advice with a mathematical model of prostate cancer. Our model predicted well the individual biomarker series of patients with prostate cancer that are used as clinical samples

日本脳炎ウイルスの生態学的研究1966年及び1967年の野外調査成績

Serial survey on the ecology of Japanese encephalitis (JE) virus was made in 1966 and 1967. In spring in the both years, wild caught females of Culex tritaeniorhynchus and many other species including a great number of hibernated females were examined for JE virus. In 1967, besides the above, wild caught females in spring were forced to engorge blood from susceptible pigs, and some days after, the engorged ones were examined for the virus and the pigs for HI antibody. However, no virus was found in all the mosquitoes examined, and no antibody was detected in the pigs. Nevertheless, in mid-spring in 1967 2-ME sensitive antibody was found in a few of slaughtered pigs. This facts is very important and it seems necessary to set forward the program of investigations. Japanese common snakes of six species were examined for the reservoir of JE virus in nature, but it was concluded that snakes play minor role as a natural source of the virus transmission even in the epidemic season. Despite of the fact that the starting time of epizootic in pigs and of the occurrence of infected mosquitoes was nearly the same in 1966 and 1967, the duration and size of the infection in mosquitoes and of the epidemic in men were shorter and smaller in 1967 than in the previous year. The reason seems that the larger number of infected mosquitoes at the starting time in late June,1967 caused earlier and more rapid rise in the HI antibody possessing rate of pigs at the early days of epizootic in them reducing the remaining rate of susceptible pigs as faster as about a half-month than in 1966, and this, in turn, caused subsequent infections in mosquitoes and then in men to be shorter in duration and smaller in size.前年に引き続き,1966年及び1967年に日本脳炎ウイルスの生態学的調査を行つた.両年の春,野外で採集した,多数の越年雌成虫を含むコガタアカイエカ及び他の数種の蚊からのウイルス分離を試みた.更に1967年の春には,野外採集蚊を感受性豚から吸血させ,数日後に吸血蚊からはウイルス分離を,吸血された豚からはウイルス分離とHI抗体の検出を試みた,しかし,上記の何れの蚊からもウイルスは発見されず,何れの豚からも抗体は認められなかつた.それにも拘らず1967年の春には少数のと場豚から2-ME感受性抗体が検出された.この事実は注目に値し,今後この方面からの研究が必要である.野外で採集した6種の蛇について調査した結果,蛇は日本脳炎ウイルスの伝搬源としては,日本脳炎の流行期においても,重要な役割を果していないものと結論される.豚における日本脳炎ウイルスの汚染及び感染蚊出現の開始時期は1966年と1967年とで殆んど同じであつたが,蚊における感染及び人における流行の期間と大きさは1966年には1967年におけるよりも長く,かつ大きかつた.従つて,これは1967年におけるように,流行の開始時期に感染蚊が多く,豚における汚染の上昇が前年に比較して半月ほど早く,かつ急激であつた.このことが感受性豚を少なくし,従って蚊における感染及び人における感染を短かく,そして小さくしたものと思われる

Detection of Strong Millimeter Emission from the Circumstellar Dust Disk Around V1094 Sco: Cold and Massive Disk around a T Tauri Star in a Quiescent Accretion Phase?

We present the discovery of a cold massive dust disk around the T Tauri star V1094 Sco in the Lupus molecular cloud from the 1.1 millimeter continuum observations with AzTEC on ASTE. A compact ($r\lesssim$320 AU) continuum emission coincides with the stellar position having a flux density of 272 mJy which is largest among T Tauri stars in Lupus. We also present the detection of molecular gas associated with the star in the five-point observations in $^{12}$CO J=3--2 and $^{13}$CO J=3--2. Since our $^{12}$CO and $^{13}$CO observations did not show any signature of a large-scale outflow or a massive envelope, the compact dust emission is likely to come from a disk around the star. The observed SED of V1094 Sco shows no distinct turnover from near infrared to millimeter wavelengths, which can be well described by a flattened disk for the dust component, and no clear dip feature around 10 \micron suggestive of absence of an inner hole in the disk. We fit a simple power-law disk model to the observed SED. The estimated disk mass ranges from 0.03 to $\gtrsim$0.12 M_\sun, which is one or two orders of magnitude larger than the median disk mass of T Tauri stars in Taurus.Comment: 18 pages, 4 figures, accepted for publication in Ap

日本脳炎伝搬蚊,特にコガタアカイエカの生態 : I. 1965年の成績

The ecology of vector mosquitoes of Japanese Encephalitis is essential to obtain a satisfactory understanding of the epidemiology of the disease. In this connection, the relative abundance, host preference, and seasonal history of the mosquitoes in Nagasaki area were investigated in 1965. Culex tritaeniorhynchus is a most abundant species in farm villages, and is strongly zoophilic. The overwintered females begin to appear in late March or early April; adults of both sexes originated from them appear in middle or late May; the population density thereafter is nearly unchanged until the maximum period in density from middle July to late August; the number of mosquitoes decreases abruptly in early September and thereafter a very small number of them are only collected till early October. The day length seems to be a controlling factor in determining the gonoactivity of the females of C. tritaeniorhynchus rather than the temperature under certain conditions. The seasonal prevalence of this mosquito is compared also with those of the other four dominant species, Culex vishnui, Aedes vexans nipponii, Armigeres subalbatus and Anopheles sinensis.牛舎,豚舎,山羊舎,鶏舎,人家において,及びドライアイストラップ,二重蚊帖を用いて,長崎地方の19部落で,1965年の早春から初冬まで,定期的又は不定期的に蚊の採集を行なった.また,蚊の飼育実験をも研究室で実施した.得られた結果は次の通りである.1)合計して,18種149,100個体の蚊が採集された.最も多い種はコガタアカイエカであり,全体の72.85%を占めている.次いで,シロハシイエカ,シナハマダラカ,オオタロヤブカ,アカイエカがこの順に多く,他の種類は極めて少ない.ここで,アカイエカが余り多くないのは,人家や鶏舎での採集回数が少なかったことによると思われる.2)各々の種類の全採集蚊数に対する百分率組成を,採集方法別に算出,比較して,吸血嗜好性を吟味した.その結果,コガタアカイエカは大動物及び鳥類を,シロハシイエカは鳥類及び大動物を,シナハマダラカとキンイロヤブカは大動物を,アカイエカは人類及び鳥類を好むことがわかった.3)コガタアカイエカの越冬雌成虫は,3月下旬又は4月上旬に出現し始め,4月下旬にその活動の山がある.新生第一世代の成虫は5月中,下旬に出現する.その後個体数は殆んど変らないか幾分減少して,7月下旬乃至8月下旬の最盛期を迎える.9月上旬になると個体数は激減して,その後10月上旬まで極く少数の雌成虫が採集されるのみとなる.4)コガタアカイエカ雌成虫の個体数が9月上旬に激減することから,大多数の雌成虫がこの頃から越年に入るものと思われる.本種雌成虫の生殖活動性を決定する要因としては,温度よりもむしろ日長時間が少なく共ある条件下では重要と考えられる.5)シロハシイエカは7月中旬～9月上旬に,シナハマダラカは4月上・中旬及び7月下旬～9月中旬に,キンイロヤブカは5月中旬～8月上旬に,オオクロヤブカは7月～9月に,盛に活動する