Hierarchy of B\"acklund Transformation Groups of the Painlev\'e Systems

For each Painlev\'e system P_J except the first one, we have a B\"acklund transformation group which is a lift of an affine Weyl group. In this paper, we show that the B\"acklund transformation groups for J=V,IV,III,II are successively obtained from that for J=VI by the well known degeneration or confluence processes.Comment: 11 pages, to be published in J. Math. Soc. Japa

炭素窒素安定同位体比を用いた広島湾の海産生物24種の栄養段階の推定

本研究は広島湾に生息する魚類や頭足類などの栄養段階を炭素・窒素安定同位体分析を用いて明らかにした。分析した魚類の中で最もδ15N値が低かったのはカタクチイワシとサヨリの14.4‰で，逆に高かったのはカサゴの16.8‰であった。δ13C 値が低かったのはサヨリとスズメダイの-17.6‰で，高かったのはマダイとシロギスの-15.3‰であった。頭足類を加えると，アオリイカのδ15N 値とδ13C 値は最も高く，それぞれ17.3‰と-14.8‰であった。このような種間の栄養段階の違いは，食性や栄養源の違いを反映していると考えられた。本研究結果は，瀬戸内海でも屈指の漁場として知られている広島湾において，魚類資源の持続的利用を行うために有益な知見となるであろう。Stable isotopes can provide useful knowledge about sources and processes within an ecosystem. The stable isotopes of carbon (δ13C) and nitrogen (δ15N) were used to investigate trophic relationships of relatively commercially important 21 finfish species, cephalopods in Hiroshima Bay. Among 21 finfish species, the lowest mean δ15N of 14.4‰ was recorded for Engraulis japonicus and Hyporhamphus sajori while the highest mean δ15N of 16.8‰ was recorded for Sebasticus marmoratus. The lowest and highest mean δ13C were noted -17.6‰ for Chromis notata and H. sajori, and -15.3‰ for Pagrus major and Sillago japonica, respectively. Including with cephalopods, the highest mean δ13C and δ15N noted at -14.8‰ and 17.3‰ for Sepioteuthis lessoniana. Information of stable isotope variation and trophic level in aquatic species of Hiroshima Bay can be used for monitoring and managing sustainable fisheries

Hybrid Surgery for Portosystemic Encephalopathy in a Patient with Liver Cirrhosis: a case report

Regarding the treatment for a portosystemic shunt, surgical or interventional radiological closure of the shunt was established. Interventional radiology including balloon-occluded retrograde transvenous obliteration can worsen portal hypertension and create a large thrombus close to the major venous system in the case of a huge portosystemic shunt. In contrast, it is also difficult to treat some cases through surgery alone when huge complicated shunts exist very deep in the body. Herein, we report a successful case of surgical shunt ligation for portosystemic encephalopathy in a hybrid operation room that enabled intraoperative angiography and computed tomography. A 62-year-old woman with chronic hepatitis C was referred to our hospital due to high levels of serum ammonia and hepatic encephalopathy. She had a massive, complicated portosystemic shunt from the inferior mesenteric vein to the left renal vein but did not have esophageal or gastric varices. It was difficult to occlude the portosystemic shunt by interventional radiologic techniques because the shunt had an extremely large amount of blood flow and many collateral routes. We performed the shunt ligation in the hybrid operation room. Intraoperative angiography provided detailed information about the portosystemic shunt, such as direction or volume of blood flow and collateral routes in real time. Her encephalopathy disappeared completely and she remains healthy with improved liver functional reserve to date. In conclusion, this is a successful case of a hybrid operation for an extremely large and complicated portosystemic shunt, providing for intraoperative angiography as a safe and reliable surgical treatment for portosystemic encephalopathy in patients with liver cirrhosis

Use of the index of pulmonary vascular disease for predicting long-term outcome of pulmonary arterial hypertension associated with congenital heart disease

AimsLimited data exist on risk factors for the long-term outcome of pulmonary arterial hypertension (PAH) associated with congenital heart disease (CHD-PAH). We focused on the index of pulmonary vascular disease (IPVD), an assessment system for pulmonary artery pathology specimens. The IPVD classifies pulmonary vascular lesions into four categories based on severity: (1) no intimal thickening, (2) cellular thickening of the intima, (3) fibrous thickening of the intima, and (4) destruction of the tunica media, with the overall grade expressed as an additive mean of these scores. This study aimed to investigate the relationship between IPVD and the long-term outcome of CHD-PAH.MethodsThis retrospective study examined lung pathology images of 764 patients with CHD-PAH aged <20 years whose lung specimens were submitted to the Japanese Research Institute of Pulmonary Vasculature for pulmonary pathological review between 2001 and 2020. Clinical information was collected retrospectively by each attending physician. The primary endpoint was cardiovascular death.ResultsThe 5-year, 10-year, 15-year, and 20-year cardiovascular death-free survival rates for all patients were 92.0%, 90.4%, 87.3%, and 86.1%, respectively. The group with an IPVD of ≥2.0 had significantly poorer survival than the group with an IPVD <2.0 (P = .037). The Cox proportional hazards model adjusted for the presence of congenital anomaly syndromes associated with pulmonary hypertension, and age at lung biopsy showed similar results (hazard ratio 4.46; 95% confidence interval: 1.45–13.73; P = .009).ConclusionsThe IPVD scoring system is useful for predicting the long-term outcome of CHD-PAH. For patients with an IPVD of ≥2.0, treatment strategies, including choosing palliative procedures such as pulmonary artery banding to restrict pulmonary blood flow and postponement of intracardiac repair, should be more carefully considered