Beneficial effect of EPC-K1 on the survival of warm ischemic damaged graft in rat cardiac transplantation.

A newly introduced compound, EPC-K1, represents a phosphate diester linkage of vitamin E and vitamin C. The effect of EPC-K1 on the reperfusion injury was evaluated in a heterotopic cardiac transplantation model using syngenic combination rats. Prior to the warm ischemia, 12mg EPC-K1/kg was administered intravenously to donor rats. After 15 min of warm ischemic time, hearts were harvested and perfused with 4 degrees C saline. After completion of the transplantation, recipient rats were also treated with intravenous 12 mg EPC-K1/kg, before reperfusion. Saline was used instead of EPC-K1 for both donors and recipients in the control group. On the 7th post-transplantation day, graft survival was 7 out of 8 in EPC-K1 group, versus 1 out of 9 in the control group (p &#60; 0.001). Thiobarbituric acid-reactive substance levels in the recipient serum, three hours after reperfusion, were significantly limited, in the group in which EPC-K1 was administered only to donors. But it was not possible to clarify whether the effect of EPC-K1 is primarily at the donor or recipient levels at this time. These results indicate that EPC-K1 may reduce reperfusion injury after cardiac transplantation. This beneficial effect may be mediated by the hydroxyl radical scavenging properties of EPC-K1.</p

自己血小板貯血における採血前ヘパリン投与が採取血小板の凝集能に及ぼす影響に関する検討

心臓大血管の手術において術中止血に難渋する場合や大量輸血を要する場合がある.特に血小板製剤は供給量が限られており,自己血貯血,血小板成分貯血の有用性が報告されている.術中自己血小板採取には約90分を要するが,ヘパリンの採取血小板機能への影響は不明であり,採取終了まで人工心肺を開始できないことから,手術時間が延長しているのが現状である.ヘパリンによる自己多血小板血漿(PRP)への影響がなければ,採取と同時に手術の進行が可能となり,手術時間の短縮が期待できる.今回我々は,全身麻酔下にブタを用いて,成分採血装置COMPONENT COLLECTION SYSTEM(HAEMONETICS社)による自己血小板採取を行い,ヘパリンがPRPの血小板凝集能に与える影響を検討した.1頭のブタに対し1週間の間隔を置いて2度の採血を行い,1度目はヘパリン非投与群(N群)とヘパリン投与群(H1群)の採血を行い,2度目はヘパリン投与群のみ(H2群)採血を行った.N群とH群で採取した血小板数および血小板凝集能の比較を行った.血小板凝集能はHEMA TRACER 712(MCM社)にて測定した.本研究は川崎医科大学動物実験委員会の承認を得て行った.データ数はN群7例,H群12例(H1群7例,H2群5例)であった.PRP中の血小板数はN群で153.6±67.6×10^4 /μl,H群で142.8±47.6×104 /μlであり,有意差はなかった(p=0.6857).また,血小板の最大凝集率はN群,H群で凝集惹起物質濃度がADP2μMで32.1±9.2,24.1±13.6%(p=0.183),ADP4μMで44.6±6.4,33.5±13.3%(p=0.057),Collagen2μg/mlで43.4±28.5,28.8±16.4%(p=0.176)と有意差は認めなかったが,高濃度のADPの場合のみH群でより低い傾向にあった.今回の実験ではヘパリン投与前後で採取した自己血小板の凝集能に差は認めず,PRP中の血小板数および血小板機能はヘパリンの影響は受けないと結論できる.よって,今後は臨床での術中自己血小板採取の有用性について研究を進めていく.Homologous platelet-rich plasma (HPRP) is used during cardiovascular surgery. A shortage of homologous HPRP has been highlighted recently, and autologous platelet-rich plasma (APRP) is an alternative. It takes approximately 90 min before heparin administration to collect APRP during surgery, so this procedure delays surgical treatment. Collection of APRP after systemic heparinization (SH) could be beneficial for surgical procedures. We clarified the impact of SH on the function of collected autologous platelets. The study protocol was approved by the Animal Experiment Committee of Kawasaki Medical School (Kurashiki, Japan). We undertook collection of APRP using a COMPONENT COLLECTION SYSTEM (Haemonetics, Braintree, MA, USA) in pigs under general anesthesia. We examined the influence of heparin upon the ability of APRP to aggregate platelets. Blood collection was conducted twice from each pig at an interval of 1 week. First, we collected APRP before SH (N group), followed by sequential collection after SH (H1 group). One week after the first experiment, collection of APRP was made only after SH (H2 group). Capacity for platelet aggregation was measured using HEMA TRACER^[○!R] 712 (MCM, Tokyo, Japan) and compared between the N group and H group. Collected data were seven in the N group and twelve in the H group from six pigs. Platelet count of APRP (×104/μl) was 153.6±67.6 in the N group and 142.8±47.6 in the H group, and the difference was not significant (p=0.6857). Maximum platelet aggregation in the N group and H group was 32.1±9.2 and 24.1± 13.6% (p=0.183) in adenosine diphosphate (ADP;2μM), 44.6±6.4 and 33.5±13.3% (p=0.057) in ADP (4μM) and 43.4±28.5 and 28.8±16.4% (p=0.176) in collagen (2μg/ml). Capacity of APRP to aggregate platelets was lower in the H group compared with that in the N group, but not significantly lower. We conclude that SH does not affect the platelet count and capacity for platelet aggregation of APRP. These promising results could lead to clinical application of APRP after SH

A Case of Chronic Pancreatitis with Pseudoaneurysm Rupturing into a Pseudocyst

A 44-year-old man with alcohol-induced chronic pancreatitis was referred to our institute for evaluation of severe anemia. The hemoglobin was 2.6g/dl. The results of upper gastrointestinal and colonic examination were negative. Computed tomography and ultrasound examination revealed a pseudocyst in the head of the pancreas. A pseudoaneurysm of the anterior superior pancreaticoduodenal artery shown by angiography appeared to have caused gastrointestinal bleeding by rupturing into the pancreatic cyst connected to the main pancreatic duct. A pyrorus-preserving pancreaticoduodenectomy was performed successfully.</p

Turtle spongious ventricles exhibit more compliant diastolic property and possess larger elastic regions of connectin in comparison to rat compact left ventricles

There is growing evidence that ventricular diastolic dysfunction is a major pathological factor in heart failure. Although many basic and clinical studies have been reported, there is little information available about the comparative and evolutionary aspects of the diastolic properties of vertebrate ventricles. Cardiac tissues in extant vertebrates are roughly divided into two types; compact myocardium in mammals and aves, and spongious myocardium in amphibians and some of reptilians. Here we compared the mechanical properties of both whole ventricles and the biochemical properties of isolated cardiomyocytes (including intracelluar Ca2+ ([Ca2+]i) handling, and the lengths of elastic regions of connectin, a protein that determines elasticity of cardiomyocytes) between spongious ventricles of turtles (Trachemys scripta elegans) and compact ventricles of Wister rats. Ventricular diastolic function is composed of active relaxation and passive compliance. We investigated ventricular compliance by analyzing normalized end-diastolic pressure-volume relationship (EDPVR) of diastolic-arrested ventricles to compare different-sized hearts and ventricular relaxation by determining logistic time constants of pressure decay. We measured [Ca2+]i handling using isolated cardiomyocytes. Stiffness constants obtained from exponential curve fitting were significantly larger in rat left ventricles (LVs) compared with turtle ventricles (99.0 ± 7.3 and 2.07 ± 0.62, respectively) showing that rat LVs were much stiffer than turtle ventricles. Normalization of EDPVRs revealed that the turtle ventricle and rat LV exhibit species-specific characteristics in ventricular compliance. At the cellular level, the initial normalized stiffness of rat cardiomyocytes (8.03 ± 1.33 kPa) was 2.8 times higher than in those of the turtle (2.82 ± 0.38 kPa), showing that turtle cardiomyocytes were much more compliant than those of rats. With respect to relaxation, the time constant of isovolumic relaxation in the rat LV pressuretime curve was significantly smaller than that in turtle ventricles (10.7 ± 0.96 and 67.4 ± 3.55 ms, respectively), resulting in early-phase-dominant ventricular filling patterns in rats. The time to peak [Ca2+]i and the decay time after peak [Ca2+]i in turtle cardiomyocytes were significantly longer than in rat. The numbers of amino acids of the PEVK domain of connectin, which is enriched in proline, glutamic acid, valine and lysine and encodes a random coil shown to be an important region in the passive elasticity of connectin were 821 and 204 in turtle and rat ventricles, respectively. These results suggest that vertebrate hearts have been becoming less compliant at the ventricle, cardiomyocyte, and molecular levels during the course of evolution. One possible physiological meaning of restricted compliance in rat ventricles could be related to a well-developed coronary circulation, because the less compliant mechanical properties of the ventricle are largely advantageous to preserve diastolic-dominant coronary arterial flow by preventing excessive ventricular expansion. Future research aimed at understanding the regulatory mechanisms of cardiac connectin among vertebrates may contribute to the investigation of the therapeutic potential of diastolic heart failure

Annual report by The Japanese Association for Thoracic Surgery

All data regarding cardiovascular surgery and thoracic surgery were obtained from NCD, whereas data regarding esophageal surgery were collected from survey questionnaire by The Japanese Association for Thoracic Surgery forms because NCD of esophageal surgery does not include non-surgical cases (i.e., patients with adjuvant chemotherapy or radiation alone). Based on the change in data aggregation, there are several differences between this 2015 annual report and previous annual reports: the number of institutions decreased in each category from 578 (2014) to 568 (2015) in cardiovascular, from 762 to 714 in general thoracic and from 626 to 571 in esophageal surgery. Because more than two departments in the same institute registered their data to NCD individually, we cannot calculate correct number of institutes in this survey. Then, the response rate is not indicated in the category of cardiovascular surgery (Table 1), and the number of institutions classified by the operation number is also not calculated in the category of cardiovascular surgery (Table 2)