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Objectives: The aim of this study is to analyze long-term results of the total aortic arch replacement with the frozen elephant trunk technique for primary chronic type B aortic dissection., Methods: Among 322 patients who had the frozen elephant trunk technique, 43 (13.4%) patients (median age, 64.0 years) with primary chronic type B aortic dissection were analyzed. The patients underwent surgery at a median of 27.0 months after the onset of aortic dissection. The false lumen was patent in 30 (69.8%) patients preoperatively., Results: Two patients suffered paraplegia and another died of cerebral infarction. Complete thrombosis of the peri-stent false lumen was achieved in 36 (83.7%) patients. Overall survival, freedom from aortic events, and freedom from aortic reintervention were 83.5%, 37.2%, and 42.2% at 5 years, respectively. Survival rates of the patients with or without aortic events were 75.0% and 95.8% at 5 years (Log-rank, p = 0.22). Late aortic events occurred in 19 (44.2%) patients including distal stent graft-induced new entry, type Ib endoleak, and false lumen dilation. The ratio of the stent graft diameter to the preoperative short axis diameter of the true lumen (hazard ratio, 1.90; 95% confidence interval, 1.01-3.59), and the maximal diameter of a postdissection aneurysm (1.07; 1.01-1.12) were the significant multivariate risk predictors of late aortic events., Conclusions: Late aortic events occurr fairly frequently, and new strategies need to be explored to enhance the effectiveness of this procedure in the future., (© 2024. The Author(s), under exclusive licence to The Japanese Association for Thoracic Surgery.)

Background: The perioperative use of the Impella 5.5 has been increasing recently; however, the left ventricular perforation by this device during surgery has not been reported to date., Case Presentation: Postinfarction ventricular septal rupture in a 75-year-old man was successfully repaired with support of a single Impella 5.5 device used for consecutive 28 days perioperatively. The patient underwent surgery after 16 days of Impella support. During surgery, the Impella was left in place expecting its use for left ventricular unloading after the operation. After aortic cross-clamp, when the apex was carefully lifted, the tip of the Impella almost protruded from the posterior wall, and could be seen through the epicardium. The aorta was unclamped briefly, the Impella was pulled out several centimeters, and the aorta was cross-clamped again. The ventricular septal rupture was repaired by the double-layer patch technique via the right ventricle. Immediately before the chest closure, the free wall of the LV ruptured and blood rapidly flowed out. It was where the Impella almost protruded during cardiac arrest, and was repaired with a pledgeted monofilament mattress suture., Conclusions: A single device can be used throughout perioperative periods; however, if used during surgery, possible risk of left ventricular perforation should be well recognized since the device has no soft pigtail part at its end, and its stiff tip can directly contact the decompressed, flaccid ventricular wall during cardiac arrest., (© 2024. The Author(s).)

Various surgical approaches address complex heart disease with arch anomalies. Bilateral pulmonary artery banding (bPAB) is a strategy for critically ill patients with complex arch anomalies. Some reports argued the potential effect of bPAB on the growth of the left ventricular outflow tract (LVOT) during inter-stage after bPAB. This study aimed to analyze the LVOT growth for biventricular repair candidates with arch anomaly and systemic ventricular outflow tract (SVOT) for univentricular repair candidates with arch anomaly. This retrospective study analyzed 17 patients undergoing initial bPAB followed by arch repair. The Z-scores of LVOT and SVOT were compared between pre-bPAB and pre-arch repair. Patient characteristics, transthoracic echocardiogram data, and PAB circumferences were reviewed. The diameter of the minimum LVOT for biventricular repair (BVR) candidates, the pulmonary valve (neo-aortic valve, neo-AoV) and the pulmonary trunk (the neo-ascending aorta, neo-AAo) for univentricular repair (UVR) candidates, and the degree of aortic or neo-aortic insufficiency in each candidate was statistically analyzed. 17 patients were divided into the UVR candidates (group U) with 9 patients and the BVR candidates (group B) with 8 patients. In group B, the median value of the Z-score of the minimum LVOT increased from -3.2 (range: - 4.1 ~ - 1.0) at pre-PAB to -2.8 (range: - 3.6 ~ - 0.3) at pre-arch repair with a significant difference (p = 0.012). In group U, the median value of the Z-score of the neo-AoV increased from 0.5 (range: - 1.0 ~ 1.7) at pre-bPAB to 1.2 (range: 0.2 ~ 1.9) at pre-arch repair with a significant difference (p < 0.01). The median value of the Z-score of the neo-AAo was also increased from 3.1 (range: 1.5 ~ 4.6) to 4.3 (range: 3.1 ~ 5.9) with a significant difference (p = 0.028). The growth of the LVOT for BVR candidates and SVOT for UVR candidates during the inter-stage between bPAB and arch repair was observed. These results suggest the potential advantage of bPAB in surgical strategies. Further research is needed to validate these findings and refine surgical approaches., (© 2024. Springer Nature Japan KK, part of Springer Nature.)

A 66-year-old man presented with hemolytic anemia, which required frequent blood transfusion, 6 months after surgical repair of an ascending aortic pseudoaneurysm. Hemolysis was attributed to luminal stenosis caused by graft kinking by laboratory test, CT and four-dimensional magnetic resonance imaging. First, an Excluder cuff was placed at the stenotic site under rapid pacing, but it migrated distally. Thereafter a Palmaz XL stent was placed at the stenotic site, which led to resolution of anemia. In this case, a Palmaz XL stent was successfully used to treat hemolytic anemia caused by graft kinking following ascending aortic surgery., Competing Interests: Declaration of Conflicting InterestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Marine animals display diverse vibrant colors, but the mechanisms underlying their specific coloration remain to be clarified. Blue coloration is known to be achieved through a bathochromic shift of the orange carotenoid astaxanthin (AXT) by the crustacean protein crustacyanin, but other examples have not yet been well investigated. Here, we identified an ependymin (EPD)-related water-soluble blue carotenoprotein responsible for the specific coloration of the marine blue sponge Haliclona sp. EPD was originally identified in the fish brain as a protein involved in memory consolidation and neuronal regeneration. The purified blue protein, designated as EPD-related blue carotenoprotein-1, was identified as a secreted glycoprotein. We show that it consists of a heterodimer that binds orange AXT and mytiloxanthin and exhibits a bathochromic shift. Our crystal structure analysis of the natively purified EPD-related blue carotenoprotein-1 revealed that these two carotenoids are specifically bound to the heterodimer interface, where the polyene chains are aligned in parallel to each other like in β-crustacyanin, although the two proteins are evolutionary and structurally unrelated. Furthermore, using reconstitution assays, we found that incomplete bathochromic shifts occurred when the protein bound to only AXT or mytiloxanthin. Taken together, we identified an EPD in a basal metazoan as a blue protein that decorates the sponge body by binding specific structurally unrelated carotenoids., Competing Interests: Conflict of interest The authors declare that they have no conflicts of interest with the contents of this article., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)

Competing Interests: None declared.

Background: Aortic valve neocuspidization (AVNeo) has emerged as a promising aortic valve procedure, and is expected to have a larger effective orifice area (EOA) than commercially available bioprostheses. It is, however, unclear which indices could facilitate left ventricular (LV) reverse remodeling after AVNeo. The aim of this study is to verify the impact of global left ventricular afterload on the LV reverse remodeling following AVNeo., Methods: Data-available consecutive 38 patients (median age, 77; interquartile range, 72.8-82.0) undergoing AVNeo for severe aortic stenosis were enrolled in this study. Preoperative and the last follow-up echocardiographic data were retrospectively analyzed including the valvuloarterial impedance (Zva), a marker of global LV afterload. Reduction in LV geometry index (LVGI) and relative wall thickness (RWT) were used as an indicator for LV reverse remodeling., Results: The Zva reduced in 24 patients (63.2%) during the follow-up period (median, 12 months). Reduction in Zva significantly correlated to improvement of LV geometry (LVGI (r = 0.400, p = 0.013) and RWT (r = 0.627, p < 0.001)), whereas increase in EOA index did not significantly correlate to LVGI (r = 0.009, p = 0.957), or RWT (r = 0.105, p = 0.529)). The reduction in Zva was the multivariate predictor of LV reverse remodeling., Conclusions: Low global LV afterload led to significant LV reverse remodeling even after AVNeo, which could achieve better valve performance than the conventional bioprostheses., (© 2022. The Author(s).)

Pancreaticoduodenal artery aneurysm (PDAA) is a rare disease without treatment guidelines. We present two patients with PDAA. The first patient was a 70-year-old man with a pseudoaneurysm in the anterior superior pancreaticoduodenal artery (ASPDA), for which we achieved exclusion by endovascular coil embolization. The second patient was a 63-year-old woman with a PDAA in the ASPDA with celiac axis obstruction. Endovascular coil embolization of the aneurysm and the ASPDA was successful without visceral organ ischemia. Endovascular treatment is effective for PDAAs, but careful evaluation of collateral circulation is vital in PDAAs with celiac axis obstruction., Competing Interests: Disclosure StatementAll authors have no conflict of interest., (© 2020 The Editorial Committee of Annals of Vascular Diseases.)

Objectives: We retrospectively analyzed our experience of mitral valve repair for native mitral valve endocarditis in a single institution., Methods: From January 1991 to October 2011, 171 consecutive patients underwent surgery for infective endocarditis. Of these, 147 (86%) had mitral valve repair. At the time of surgery, 98 patients had healed (group A) and 49 had active infective endocarditis (group B). Repair procedures included resection of all infected tissue and thick restricted post-infection tissue, leaflet and annulus reconstruction with treated autologous pericardium, chordal reconstruction with polytetrafluoroethylene sutures, and ring annuloplasty if necessary. Fifty-two (35%) patients required concomitant procedures. The study endpoints were overall survival, freedom from reoperation, and freedom from valve-related events. The median follow-up was 78 months., Results: There was one hospital death (hospital mortality 0.7%). Survival at 10 years was 88.5% ± 3.5% with no significant difference between the two groups ( p  = 0.052). Early reoperation was required in 4 patients in group B due to persistent infection or procedure failure. Freedom from reoperation at 5 years was 99% ± 1.0% in group A and 89.6 ± 4.0% in group B ( p  = 0.024). Event-free survival at 10 years was 79.3% ± 4.8% (group A: 83.4% ± 5.9%, group B: 72.6% ± 6.9%, p  = 0.010)., Conclusions: Mitral valve repair was highly successful using autologous pericardium, chordal reconstruction, and ring annuloplasty if required. Long-term results were acceptable in terms survival, freedom from reoperation, and event-free survival. Mitral valve repair is recommended for mitral infective endocarditis in most patients.

Background: Systolic aortic root expansion is reported to facilitate valve opening, but the precise dynamics remain unknown. A sonometric study with a high data sampling rate (200 to 800 Hz) was conducted in an acute ovine model to better understand the timing, mechanisms, and shape of aortic valve opening and closure., Methods: Eighteen piezoelectric crystals were implanted in 8 sheep at each annular base, commissures, sinus of Valsalva, sinotubular junction, nodulus of Arantius, and ascending aorta (AA). Geometric changes were time related to pressures and flows., Results: The aortic root was hemodynamically divided into left ventricular (LV) and aortic compartments situated, respectively, below and above the leaflets. During isovolumetric contraction (IVC), aortic root expansion started in the LV compartment, most likely due to volume redistribution in the LV outflow tract below the leaflets. This expansion initiated leaflet separation prior to ejection (2.1%±0.5% of total opening area). Aortic compartment expansion was delayed toward the end of IVC, likely related to volume redistribution above the leaflets due to accelerating aortic backflow toward the aortic valve and coronary flow reduction due to myocardial contraction. Maximum valve opening during the first third of ejection acquired a truncated cone shape [leaflet free edge area smaller than annular base area (-41.5%±5.5%)]. The distal orifice became clover shaped because the leaflet free edge area is larger than the commissural area by 16.3%±2.0%., Conclusions: Aortic valve opening is initiated prior to ejection related to delicate balance between LV, aortic root, and coronary dynamics. It is clover shaped at maximum opening in systole. A better understanding of these mechanisms should stimulate more physiological surgical approaches of valve repair and replacement., Competing Interests: Conflicts of Interest: The authors have no conflicts of interest to declare.

Background: Coronary artery aneurysm (CAA) is defined as dilatation exceeding 1.5 times the width of the normal adjacent coronary artery segments. CAA usually causes few symptoms, and rupture is rare, but can be lethal due to cardiac tamponade when it does occur., Case Presentation: A 79-year-old woman presented with presyncope and back pain. Emergency surgery was performed based on a diagnosis of cardiac tamponade due to either rupture of coronary arteriovenous fistula or CAA. At surgery, a rupture site was located on the wall of the giant CAA, with a diameter of 55 mm, originating from the ostium of the right coronary artery. Suture closure of the inflow and outflow of the aneurysm was performed, and the aneurysmal cavity was obliterated by multiple sutures. The patient made an uneventful recovery and was discharged from hospital on postoperative day 13., Conclusion: On the basis of this case, we propose considering rupture of a CAA as one of the causes of cardiac tamponade.

Citrobacter sp. S-77 [NiFe]-hydrogenase harbors a standard [4Fe-4S] cluster proximal to the Ni-Fe active site. The presence of relocatable water molecules and a flexible aspartate enables the [4Fe-4S] to display redox-dependent conformational changes. These structural features are proposed to be the key aspects that protect the active site from O2 attack.

Hydrogenophilus spp., which are moderately thermophilic aerobic betaproteobacteria, are widely distributed in geothermal environments. They fix carbon dioxide via the Calvin-Benson-Bassham cycle and exhibit rapid autotrophic growth using hydrogen as an energy source. Here, we report the complete genome sequence of Hydrogenophilus thermoluteolus strain TH-1.

The design of protein oligomers with multiple active sites has been gaining interest, owing to their potential use for biomaterials, which has encouraged researchers to develop a new design method. Three-dimensional domain swapping is the unique phenomenon in which protein molecules exchange the same structural region between each other. Herein, to construct oligomeric heme proteins with different active sites by utilizing domain swapping, two c-type cytochrome-based chimeric proteins have been constructed and the domains swapped. According to X-ray crystallographic analysis, the two chimeric proteins formed a domain-swapped dimer with two His/Met coordinated hemes. By mutating the heme coordination structure of one of the two chimeric proteins, a domainswapped heterodimer with His/Met and His/H 2 O coordinated hemes was formed. Binding of an oxygen molecule to the His/H 2 O site of the heterodimer was confirmed by resonance Raman spectroscopy, in which the Fe-O 2 stretching band was observed at 580 cm -1 for the reduced/oxygenated heterodimer (at 554 cm -1 under an 18 O 2 atmosphere). These results show that domain swapping is a useful method to design multiheme proteins., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Background: Conventional indices such as prosthetic valve effective orifice area (EOA) or transvalvular pressure gradients (TPG) may be unreliable in predicting left ventricular (LV) reverse remodeling after aortic valve replacement (AVR). We hypothesized that the global LV afterload, including valvular and arterial impedance, could influence LV reverse remodeling after AVR., Methods: Twenty-three consecutive aortic-stenosis patients (mean age, 76 ± 6.4 years) underwent isolated AVR using contemporary externally wrapped pericardial valves (19 mm, 10 patients; 21 mm 11; 23 mm, 2). Valvuloarterial impedance (Zva), a marker of global LV afterload, was measured on serial echocardiography in addition to indexed EOA, energy loss index (ELI), mean TPG, and stroke work loss. LV mass regression was used as a parameter of LV reverse remodeling., Results: The Zva significantly decreased after AVR (5.05 ± 1.7 mmHg/mL/m 2 , pre-operatively; 3.12 ± 1.0, postoperatively; 3.13 ± 0.89, at last follow-up) in parallel with increased indexed EOA (0.46 ± 0.13 cm 2 /m 2 ; 1.13 ± 0.24; 0.96 ± 0.19), ELI (0.55 ± 0.21 cm 2 /m 2 ; 1.74 ± 0.52; 1.47 ± 0.42), and decreased mean TPG (50.2 ± 19.6 mmHg; 11.1 ± 5.4; 14.7 ± 5.8). The stroke work loss also decreased (26.3 ± 8.5 %; 8.65 ± 4.0; 9.36 ± 3.4). The Zva at last follow-up was significantly correlated with LV mass regression (correlation coefficient, r = - 0.48; P = 0.002), and was a significant predictor of LV reverse remodeling on multiple regression analysis (adjusted odds ratio, -0.43; 95% confidence interval, -31.3 to -0.67, P = 0.042), while indexed EOA, ELI, mean TPG, or systemic arterial compliance were not., Conclusions: The postoperative Zva was significantly associated with LV mass regression after AVR. Maintaining low global LV afterload following AVR may enhance LV reverse remodeling., (© 2017 Wiley Periodicals, Inc.)

Background: Pericardial effusion (PE) is a common finding in patients who had chronic cardiac failure, who had undergone cardiac surgery, or who had certain other benign and malignant diseases. PE ranges in severity from mild, asymptomatic effusions to cardiac tamponade. Although a thoracoscopic pericardial window (TPW) is a minimally invasive surgical option for patients with PE, there are few published data regarding the outcomes of TPW for PE. We investigated the contribution of the TPW to the treatment of PEs that are recurrent or difficult to drain percutaneously., Methods: We conducted a retrospective chart review of the indications for TPW that included data on preoperative, intraoperative, and postoperative variables; morbidity; recurrence; and survival. Fourteen consecutive patients with PE that was recurrent or difficult to drain percutaneously and who underwent treatment with a TPW were enrolled in this study. Trocars for passage of the thoracoscope and surgical instruments were introduced through two or three incisions. Mini-thoracotomy was also performed in patients with hemopericardium and loculated fibrinous effusions. All patients were evaluated by face-to-face interviews, transthoracic echocardiography (TTE), and chest radiography 3-6 months after the TPW was obtained., Results: The mean age of the patients was 70 years (range 28-83 years). The operative time was 72.1 ± 29.5 min. Six patients had undergone open heart surgery during the month prior to their presentation with PE. No intraoperative or postoperative complications occurred, although PE had recurred in one patient. Two patients died of malignant disease several months after the TPW. The cardiothoracic ratio (determined on chest radiographs) and the ejection fraction ratio (determined using TTE) had improved at the 3- and 6-month follow-up evaluations (p < 0.0001 and p = 0.012, respectively). Some patients could discontinue diuretics after the procedure, as assessed by the cardiologist based on symptom alleviation, chest radiography, and TTE findings., Conclusions: For patients with PEs that are recurrent or difficult to drain percutaneously, TPW is an effective, safe surgical approach in terms of cardiac function and radiological findings.

Three patients underwent left upper lobectomy with arterioplasty of left pulmonary artery trunk for lung cancer. For pulmonary arterioplasty, wide wedge resection and patch plasty with autologous pericardium was performed. No in-hospital death or no postoperative complications due to arterioplasty was encountered. The mean follow-up period was 3.6 years and long-term patency of the reconstructed pulmonary artery was confirmed by computed tomography in all patients.

Protein nanostructures have been gaining in interest, along with developments in new methods for construction of novel nanostructures. We have previously shown that c -type cytochromes and myoglobin form oligomers by domain swapping. Herein, we show that a four-helix bundle protein cyt cb 562 , with the cyt b 562 heme attached to the protein moiety by two Cys residues insertion, forms a domain-swapped dimer. Dimeric cyt cb 562 did not dissociate to monomers at 4 °C, whereas dimeric cyt b 562 dissociated under the same conditions, showing that heme attachment to the protein moiety stabilizes the domain-swapped structure. According to X-ray crystallographic analysis of dimeric cyt cb 562 , the two helices in the N-terminal region of one protomer interacted with the other two helices in the C-terminal region of the other protomer, where Lys51-Asp54 served as a hinge loop. The heme coordination structure of the dimer was similar to that of the monomer. In the crystal, three domain-swapped cyt cb 562 dimers formed a unique cage structure with a Zn-SO 4 cluster inside the cavity. The Zn-SO 4 cluster consisted of fifteen Zn 2+ and seven SO 4 2- ions, whereas six additional Zn 2+ ions were detected inside the cavity. The cage structure was stabilized by coordination of the amino acid side chains of the dimers to the Zn 2+ ions and connection of two four-helix bundle units through the conformation-adjustable hinge loop. These results show that domain swapping can be applied in the construction of unique protein nanostructures.

High-order oligomers of Hydrogenobacter thermophilus cytochrome c552 increased with the insertion of more Gly residues between Ala18 and Lys19 at the major hinge loop of the wild-type protein. N-Terminal domain swapping and C-terminal domain swapping were elucidated by using X-ray crystallography for the mutant with the insertion of three Gly residues at the hinge loop.

Enzymatic regio- and stereoselective hydroxylation are valuable for the production of hydroxylated chiral ingredients. Proline hydroxylases are representative members of the nonheme Fe(2+)/α-ketoglutarate-dependent dioxygenase family. These enzymes catalyze the conversion of L-proline into hydroxy-L-prolines (Hyps). L-Proline cis-4-hydroxylases (cis-P4Hs) from Sinorhizobium meliloti and Mesorhizobium loti catalyze the hydroxylation of L-proline, generating cis-4-hydroxy-L-proline, as well as the hydroxylation of L-pipecolic acid (L-Pip), generating two regioisomers, cis-5-Hypip and cis-3-Hypip. To selectively produce cis-5-Hypip without simultaneous production of two isomers, protein engineering of cis-P4Hs is required. We therefore carried out protein engineering of cis-P4H to facilitate the conversion of the majority of L-Pip into the cis-5-Hypip isomer. We first solved the X-ray crystal structure of cis-P4H in complex with each of L-Pro and L-Pip. Then, we conducted three rounds of directed evolution and successfully created a cis-P4H triple mutant, V97F/V95W/E114G, demonstrating the desired regioselectivity toward cis-5-Hypip.

Protein design is a useful method to create novel artificial proteins. A rational approach to design a heterodimeric protein using domain swapping for horse myoglobin (Mb) was developed. As confirmed by X-ray crystallographic analysis, a heterodimeric Mb with two different active sites was produced efficiently from two surface mutants of Mb, in which the charges of two amino acids involved in the dimer salt bridges were reversed in each mutant individually, with the active site of one mutant modified. This study shows that the method of constructing heterodimeric Mb with domain swapping is useful for designing artificial multiheme proteins., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Transaortic septal myectomy, known as Morrow's procedure, is a standard treatment for hypertrophic obstructive cardiomyopathy (HOCM). The case is described of a 58-year-old male patient who suffered a repetition of syncope due to HOCM, in whom septal myectomy was performed. As resection of the hypertrophied septum using Morrow's procedure was considered insufficient by palpation to release mitral regurgitation (MR) and systolic anterior motion of the mitral valve, the surgical approach was changed such that the right ventricular outflow tract and ventricular septum was incised. The residual hypertrophied septum was successfully resected to the base of the anterior papillary muscle under direct vision. Postoperative echocardiography demonstrated a dramatic improvement in the MR and left ventricular outflow tract obstruction. The patient's postoperative course was good, with cibenzoline and calcium channel blocker therapy stopped and beta-blocker therapy reduced after surgery. If resection of the hypertrophied septum using Morrow's procedure is considered insufficient, a trans-septal approach represents an adequate option to treat HOCM.

NAD+-reducing [NiFe] hydrogenases catalyze the oxidoreduction of dihydrogen concomitant with the interconversion of NAD+ and NADH. Here, the isolation, purification and crystallization of the NAD+-reducing [NiFe] hydrogenase from Hydrogenophilus thermoluteolus TH-1 are reported. Crystals of the NAD+-reducing [NiFe] hydrogenase were obtained within one week from a solution containing polyethylene glycol using the sitting-drop vapour-diffusion method and micro-seeding. The crystal diffracted to 2.58 Å resolution and belonged to space group C2, with unit-cell parameters a=131.43, b=189.71, c=124.59 Å, β=109.42°. Assuming the presence of two NAD+-reducing [NiFe] hydrogenase molecules in the asymmetric unit, VM was calculated to be 2.2 Å3 Da(-1), which corresponds to a solvent content of 43%. Initial phases were determined by the single-wavelength anomalous dispersion method using the anomalous signal from the Fe atoms.