Hemodynamic Analysis of a Microanastomosis Using Computational Fluid Dynamics

[Background] Technical issues in free flap transfer, such as the selection of recipient vessels and the positioning and method of anastomosis of the vascular pedicle, have been the subject of vigorous debate. Recent developments in computational fluid dynamics (CFD) have enabled the analysis of blood flow within microvessels. In this study, CFD was used to analyze hemodynamics in a microanastomosis. [Methods] In the fluid calculation process, the fluid domain modelizes microvessels with anastomosis. The inlet flow conditions were measured as venous waveform, and the fluid is simulated as blood. Streamlines (SL), wall shear stress (WSS), and oscillatory shear index (OSI) at the anastomosis were visualized and analyzed for observing effects from the flow field. [Results] Some flow disruption was evident as the SL passed over the sutures. The maximum recorded WSS was 13.37 Pa where the peak of a suture was exposed in the lumen. The local maximum value of the OSI was 0.182, recorded at the base of the anastomosis on the outflow side. [Conclusion] In the ideal anastomosis, the SL is disrupted as little as possible by the sutures. The WSS indicated that thrombus formation is unlikely to occur at suture peaks, but more likely to occur at the base of sutures, where the OSI is high. Tight suture knots are important in microanastomosis

Effect of right ventricular free wall longitudinal strain on all-cause death in patients with isolated severe tricuspid regurgitation and atrial fibrillation

BackgroundWith the aging population and advanced catheter-based therapy, isolated tricuspid regurgitation (TR) with atrial fibrillation (AF) has gained increased attention; however, data on the prognostic effect of isolated TR with AF are limited because of the small number of patients among those with severe TR. Recently, right ventricular (RV) longitudinal strain by two-dimensional speckle-tracking echocardiography has been reported as an excellent indicator of RV dysfunction in severe TR. However, the prognostic implications of RV longitudinal strain in isolated severe TR associated with AF remain unclear. Therefore, this study aimed to reveal the prognostic value of this index in this population.MethodsWe retrospectively studied patients with severe isolated TR associated with AF in the absence of other etiologies in the Cedars-Sinai Medical Center between April 2015 and March 2018. Baseline clinical and echocardiographic data were studied including RV systolic function evaluated by RV free wall longitudinal strain (FWLS) and conventional parameters. All-cause death was defined as the primary endpoint.ResultsIn total, 53 patients (median age, 85 years; female, 60%) with a median follow-up of 433 (60–1567) days were included. Fourteen patients (26%) died, and 66% had right heart failure (RHF) symptoms. By multivariable analysis, reduced RVFWLS was independently associated with all-cause death. Patients with RVFWLS of ≤18% had higher risk of all-cause death adjusted for age (log-rank P = 0.030, adjusted hazard ratio 4.00, 95% confidence interval, 1.11–14.4; P = 0.034). When patients were stratified into four groups by RHF symptoms and RVFWLS, the group with symptomatic and reduced RVFWLS had the worst outcome.ConclusionReduced RVFWLS was independently associated with all-cause death in patients with isolated severe TR and AF. Our subset classification showed the worst outcome from the combination of RHF symptoms and reduced RVFWLS

Serologic Markers in Relation to Parasite Exposure History Help to Estimate Transmission Dynamics of Plasmodium vivax

Plasmodium vivax infection has been gaining attention because of its re-emergence in several parts of the world. Southeastern Turkey is one of the places in which persistent focal malaria caused exclusively by P. vivax parasites occurs. Although control and elimination studies have been underway for many years, no detailed study has been conducted to understand the mechanisms underlying the ineffective control of malaria in this region. Here, for the first time, using serologic markers we try to extract as much information as possible in this region to get a glimpse of P. vivax transmission. We conducted a sero-immunological study, evaluating antibody responses of individuals living in Sanliurfa to four different P. vivax antigens; three blood-stage antigens (PvMSP119, PvAMA1-ecto, and PvSERA4) and one pre-erythrocytic stage antigen (PvCSP). The results suggest that a prior history of malaria infection and age can be determining factors for the levels and sustainability of naturally acquired antibodies. Significantly higher antibody responses to all the studied antigens were observed in blood smear-negative individuals with a prior history of malaria infection. Moreover, these individuals were significantly older than blood smear-negative individuals with no prior history of infection. These data from an area of sole P. vivax-endemic region may have important implications for the global malaria control/elimination programs and vaccine design

Effect of Saxagliptin on Endothelial Function in Patients with Type 2 Diabetes : A Prospective Multicenter Study

The dipeptidyl peptidase-4 inhibitor saxagliptin is a widely used antihyperglycemic agent in patients with type 2 diabetes. The purpose of this study was to evaluate the effects of saxagliptin on endothelial function in patients with type 2 diabetes. This was a prospective, multicenter, interventional study. A total of 34 patients with type 2 diabetes were enrolled at four university hospitals in Japan. Treatment of patients was initially started with saxagliptin at a dose of 5 mg daily. Assessment of endothelial function assessed by flow-mediated vasodilation (FMD) and measurement of stromal cell-derived factor-1α (SDF-1α) were conducted at baseline and at 3 months after treatment with saxagliptin. A total of 31 patients with type 2 diabetes were included in the analysis. Saxagliptin significantly increased FMD from 3.1 ± 3.1% to 4.2 ± 2.4% (P = 0.032) and significantly decreased total cholesterol from 190 ± 24 mg/dL to 181 ± 25 mg/dL (P = 0.002), glucose from 160 ± 53 mg/dL to 133 ± 25 mg/dL (P < 0.001), HbA1c from 7.5 ± 0.6% to 7.0 ± 0.6% (P < 0.001), urine albumin-to-creatinine ratio from 63.8 ± 134.2 mg/g to 40.9 ± 83.0 mg/g (P = 0.043), and total SDF-1α from 2108 ± 243 pg/mL to 1284 ± 345 pg/mL (P < 0.001). These findings suggest that saxagliptin is effective for improving endothelial function

OMI-VT stormに対するカテーテルアブレーション

A ６８-year-old woman with VT storm and frequent appropriate ICD therapy was referred for catheter ablation. Her past history was notable for aortic valve replacement by mechanical valve due to infectious endocarditis １７ years prior to presentation and left ventricular apical old myocardial infarction with unknown onset. At ６７ years old, She admitted to the prior hospital due to ventricular tachycardia with LBBB and superior axis at heart rate of ２１０ per minutes. Administration of amiodarone and magnesium sulfate was ineffective and cardioversion of ２００J was successfully terminated the tachycardia. Intra-cardiac defibrillator was implanted and the administration of amiodarone and mexiletine was started. ５ months after, she admitted to the hospital due to the frequent appropriate shock against the same ventricular tachycardia. Administration of lidocaine, sotalol, pilsicainide, and magnesium sulfate could not control the tachycardia and she was referred to our hospital for catheter ablation. During the first session, ventricular tachycardia was easily induced and electroanatomical mapping was performed both during tachycardia and during sinus rhythm. Late diastolic potential preceding the onset of QRS wave by ４５ms was detected at the infero-septal side of the apical aneurysm. ７．５s of the RF energy application at this site could terminate the tachycardia and thereafter no ventricular tachycardia was induced. But after dose-reduction or cessation of some anti-arrhythmic drugs, ventricular tachycardia was recurred and second session was performed. This time, no ventricular tachycardia was induced, then we performed isthmus transection and core isolation against the apical aneurysm. Thereafter no ventricular tachycardia was occurred in spite of dose-reduction or cessation of some anti-arrhythmic drugs

Details on the effect of very short dual antiplatelet therapy after drug-eluting stent implantation in patients with high bleeding risk: insight from the STOPDAPT-2 trial

Previously we briefly reported the effect of 1-month dual antiplatelet therapy (DAPT) for patients with high bleeding risk (HBR) receiving percutaneous coronary intervention (PCI) in the STOPDAPT-2 trial, but full analysis data have not been available. We conducted post hoc subgroup analysis regarding the effect of very short DAPT for HBR patients in STOPDAPT-2 trial. The primary endpoint was a 1-year composite of cardiovascular (cardiovascular death, myocardial infarction, definite stent thrombosis, or stroke) and bleeding (TIMI major/minor bleeding) outcomes. Major secondary endpoints were 1-year cardiovascular composite endpoint and bleeding endpoint. HBR was defined by the academic research consortium (ARC) HBR criteria. Among the 3009 study patients, 1054 (35.0%) were classified as HBR and 1955 (65.0%) were as non-HBR. There were no significant interactions between HBR/non-HBR subgroups and the assigned DAPT group on the primary endpoint (HBR; 3.48% vs. 5.98%, HR 0.57, 95% CI 0.32-1.03, and non-HBR; 1.81% vs. 2.36%, HR 0.78, 95% CI 0.42-1.45; P for interaction = 0.48), the major secondary cardiovascular endpoint (HBR; 3.07% vs. 4.03%, HR 0.77, 95% CI 0.40-1.48, and non-HBR; 1.41% vs. 1.61%, HR 0.89, 95% CI 0.43-1.84; P for interaction = 0.77), and the major secondary bleeding endpoint (HBR; 0.41% vs. 2.71%, HR 0.15, 95% CI 0.03-0.65, and non-HBR; 0.40% vs. 0.85%, HR 0.48, 95% CI 0.14-1.58; P for interaction = 0.22). In conclusion, the effects of 1-month DAPT for the primary and major secondary endpoints were consistent in HBR and non-HBR patients without any significant interactions. The benefit of 1-month DAPT in reducing major bleeding was numerically greater in HBR patients.Clinical trial registration Short and optimal duration of dual antiplatelet therapy after everolimus-eluting cobalt-chromium stent-2 [STOPDAPT-2]; NCT02619760

A multilevel dataset of microplastic abundance in the world’s upper ocean and the Laurentian Great Lakes

A total of 8218 pelagic microplastic samples from the world’s oceans were synthesized to create a dataset composed of raw, calibrated, processed, and gridded data which are made available to the public. The raw microplastic abundance data were obtained by different research projects using surface net tows or continuous seawater intake. Fibrous microplastics were removed from the calibrated dataset. Microplastic abundance which fluctuates due to vertical mixing under different oceanic conditions was standardized. An optimum interpolation method was used to create the gridded data; in total, there were 24.4 trillion pieces (8.2 × 104 ~ 57.8 × 104 tons) of microplastics in the world’s upper oceans

チタンメッシュトレーとPCBMによる下顎骨再建を施行した類腱型エナメル上皮腫の1例

類腱型のエナメル上皮腫(desmoplastic ameloblastoma:DA)は,エナメル上皮腫の一亜型で,豊富な膠原線維の増生からなる間質と石鹸泡状のエックス線透過像を特徴とする.DAは,X線学的に境界不明瞭で,腫瘍周囲の被膜がないため切除範囲の設定が困難で,典型的なエナメル上皮腫と比較して,再発の割合が高いと考えられている.2006年9月,58歳の男性が,下顎右側臼歯部歯肉の腫脹と顎骨の膨隆にて近医より当科を紹介受診した.画像所見において,腫瘍の境界は不明瞭で,腫瘍は下顎骨下縁にまで及んでいた.生検の結果,組織学的に類腱型のエナメル上皮腫と診断された.下顎区域切除術ならびにチタンメッシュトレーと腸骨からのPCBMによる下顎骨再建を施行した.術後4年経過した現在,再発はみられていない.Desmoplastic ameloblastoma (DA) is a variant of ameloblastoma, characterized by foamy radiolucency and desmoplastic stroma. The recurrence rate of DA is thought to be higher than that of usual ameloblastoma because the fibrous capsule surrounding the tumour is not present and decision of the resection area is difficult, corresponding to the radiographically poorly-defined tumour margin. A 58-year-old man was referred to our clinic in September 2006 because of swelling of the mandible on the right side. Radiography indicated a poorly-defined lesion that expanded to the inferior border of the mandible. We carried out a biopsy and a diagnosis of DA was made histopathologically. Then, we carried out segmental mandibulectomy and mandibular reconstruction using a titanium mesh tray and PCBM from iliac bone. No signs of recurrence have been seen for 4 years after surgery