Clinical outcomes of endoscopic detachable snare ligation for colonic diverticular hemorrhage: Multicenter cohort study.

OBJECTIVES: The hemostatic mechanism of endoscopic detachable snare ligation (EDSL) for colonic diverticular hemorrhage (CDH) is similar to that of endoscopic band ligation, which is effective and safe. However, because reports on EDSL are scarce, we conducted a two-center cohort study to evaluate its effectiveness. METHODS: This study analyzed 283 patients with CDH treated with EDSL at two Japanese hospitals between July 2015 and November 2021. Patient characteristics and clinical outcomes were retrospectively evaluated. A Kaplan-Meier analysis was performed to evaluate the cumulative probability of rebleeding after EDSL. A Cox proportional hazards regression analysis was performed to compare the effects of complete and incomplete ligation on rebleeding. RESULTS: The initial hemostasis success and early rebleeding rates were 97.9% and 11.0%, respectively. The time to hemostasis after identification of the bleeding site and total procedure time were 9 min and 44 min, respectively. Red blood cell transfusion was required for 32.9% of patients. The median hospital length of stay after EDSL was 5 days. The complete ligation rate of the early rebleeding group was significantly lower than that of the group without early rebleeding (P < 0.01). The 1-year cumulative rebleeding rate with EDSL was 28.2%. Complete ligation was associated with decreased cumulative rebleeding after EDSL (P < 0.01). One patient experienced colonic diverticulitis; however, colonic perforation was not observed. CONCLUSION: Complete ligation is associated with reduced short-term and long-term rebleeding. EDSL could be valuable for CDH because of its low rebleeding rate and the absence of serious adverse events.

Engineering of IF1 -susceptive bacterial F1 -ATPase.

IF1 , an inhibitor protein of mitochondrial ATP synthase, suppresses ATP hydrolytic activity of F1 . One of the unique features of IF1 is the selective inhibition in mitochondrial F1 (MF1 ); it inhibits catalysis of MF1 but does not affect F1 with bacterial origin despite high sequence homology between MF1 and bacterial F1 . Here, we aimed to engineer thermophilic Bacillus F1 (TF1 ) to confer the susceptibility to IF1 for elucidating the molecular mechanism of selective inhibition of IF1 . We first examined the IF1 -susceptibility of hybrid F1 s, composed of each subunit originating from bovine MF1 (bMF1 ) or TF1 . It was clearly shown that only the hybrid with the ß subunit of mitochondrial origin has the IF1 -susceptibility. Based on structural analysis and sequence alignment of bMF1 and TF1 , the five non-conserved residues on the C-terminus of the ß subunit were identified as the candidate responsible for the IF1 -susceptibility. These residues in TF1 were substituted with the bMF1 residues. The resultant mutant TF1 showed evident IF1 -susceptibility. Reversely, we examined the bMF1 mutant with TF1 residues at the corresponding sites, which showed significant suppression of IF1 -susceptibility, confirming the critical role of these residues. We also tested additional three substitutions with bMF1 residues in α and γ subunits that further enhanced the IF1 -susceptibility, suggesting the additive role of these residues. We discuss the molecular mechanism by which IF1 specifically recognizes F1 with mitochondrial origin, based on the present result and the structure of F1 -IF1 complex. These findings would help the development of the inhibitors targeting bacterial F1 .

Extracting Higher Central Charge from a Single Wave Function.

A (2+1)D topologically ordered phase may or may not have a gappable edge, even if its chiral central charge c_{-} is vanishing. Recently, it was discovered that a quantity regarded as a "higher" version of chiral central charge gives a further obstruction beyond c_{-} to gapping out the edge. In this Letter, we show that the higher central charges can be characterized by the expectation value of the partial rotation operator acting on the wave function of the topologically ordered state. This allows us to extract the higher central charge from a single wave function, which can be evaluated on a quantum computer. Our characterization of the higher central charge is analytically derived from the modular properties of edge conformal field theory, as well as the numerical results with the ν=1/2 bosonic Laughlin state and the non-Abelian gapped phase of the Kitaev honeycomb model, which corresponds to U(1)_{2} and Ising topological order, respectively. The Letter establishes a numerical method to obtain a set of obstructions to the gappable edge of (2+1)D bosonic topological order beyond c_{-}, which enables us to completely determine if a (2+1)D bosonic Abelian topological order has a gappable edge or not. We also point out that the expectation values of the partial rotation on a single wave function put a constraint on the low-energy spectrum of the bulk-boundary system of (2+1)D bosonic topological order, reminiscent of the Lieb-Schultz-Mattis-type theorems.

Complete Crystalline Topological Invariants from Partial Rotations in (2+1)D Invertible Fermionic States and Hofstadter's Butterfly.

The theory of topological phases of matter predicts invariants protected only by crystalline symmetry, yet it has been unclear how to extract these from microscopic calculations in general. Here, we show how to extract a set of many-body invariants {Θ_{o}^{±}}, where o is a high symmetry point, from partial rotations in (2+1)D invertible fermionic states. Our results apply in the presence of magnetic field and Chern number C≠0, in contrast to previous work. {Θ_{o}^{±}} together with C, chiral central charge c_{-}, and filling ν provide a complete many-body characterization of the topological state with symmetry group G=U(1)×_{ϕ}[Z^{2}⋊Z_{M}]. Moreover, all these many-body invariants can be obtained from a single bulk ground state, without inserting additional defects. We perform numerical computations on the square lattice Hofstadter model. Remarkably, these match calculations from conformal and topological field theory, where G-crossed modular S, T matrices of symmetry defects play a crucial role. Our results provide additional colorings of Hofstadter's butterfly, extending recently discovered colorings by the discrete shift and quantized charge polarization.

Effects of Material Structure on Stress Relaxation Characteristics of Rapidly Solidified Al-Fe Alloy.

An Al-Fe alloy which was produced by hot extrusion of rapidly solidified powder is a possible solution to substitute copper-based electrical conductor material due to its high strength and high electrical conductivity. However, the stress relaxation characteristic-an essential parameter as a conductor material-and the effect of the material structure have not been reported, which was the aim of the present paper. An Al-5%Fe alloy was selected as the test material. The material structures were controlled by hot extrusion practice, annealing, and cold rolling. The Al-Fe intermetallic compound particles controlled the residual stress after the stress relaxation test via the Orowan mechanism. Decreasing the mean inter-particle distance reduces the electrical conductivity. The increase in the number of dislocations by the cold rolling increased strength at room temperature without changing electrical conductivity; however, it did not have a positive effect on the stress relaxation characteristics. The stress relaxation characteristics and the electrical conductivity of the Al-Fe alloy were superior to conventional C52100 H04 phosphor bronze when compared with the case of the same mass.

Anticoagulation against portal vein thrombosis reduces mortality and liver cirrhosis-related complications: A propensity score-matched study.

AIM: Portal vein thrombosis (PVT) is one of the common complications of liver cirrhosis. Although anticoagulation contributes to thrombus resolution and is considered the first-choice treatment, its impact on patients' prognosis is still controversial. This study aimed to clarify the benefit of anticoagulation on mortality, liver function, and the incidence of liver cirrhosis-related complications in cirrhotic PVT patients. METHODS: We conducted a multicenter retrospective review in which we included 78 eligible patients with PVT out of 439. After propensity score matching, 21 cirrhotic PVT patients were included in each one of the untreated control and anticoagulation groups. RESULTS: Overall survival was significantly improved in the anticoagulation group compared with the control group (p = 0.041), along with PVT size reduction (53.3% vs. 108.2%, p = 0.009). At the time of CT follow-up, the anticoagulation group showed a lower ALBI score (p = 0.037) and its prevalence of massive ascites was significantly lower (p = 0.043) compared with the control group. The incidence of overt encephalopathy was also lower in the anticoagulation group (p = 0.041). The cumulative incidence of bleeding events did not differ significantly between the two groups. CONCLUSIONS: Anticoagulation improves the survival of patients with cirrhotic PVT. Preserved liver function and reduced risks of cirrhosis-related complications under the treatment may have contributed to a better prognosis. Given its efficacy and safety, anticoagulation is worth initiating in patients with PVT.

Effects of Hot Extrusion Temperature Conditions on the Hardness and Electrical Conductivity of Rapidly Solidified Al-Fe Alloys.

Rapidly solidified Al-Fe alloys produced by hot extrusion are a promising replacement for copper-based electrical conductors because of their light weight. However, the effects of the extrusion temperature conditions on the mechanical and electrical properties of extruded materials are unknown. The present work investigated the effects of billet preheating temperature, in situ temperature during extrusion, and additional heat treatment after extrusion on hardness and electrical conductivity. An air-jet atomized Al-2.3%Fe alloy powder was pre-sintered into cylindrical billets and then hot-extruded. The hardness of the extrudates decreased as the in situ temperature during extrusion increased above 650 K. The billet preheating temperature affected the in situ temperature during extrusion. Additional annealing after extrusion decreased the hardness. The cause of the decrease in hardness was coarsening of the grain of the aluminum matrix. The electrical conductivity increased with higher billet preheating temperatures before extrusion or additional annealing after extrusion; however, an in situ temperature rise for a few seconds during extrusion did not affect the conductivity. The increase in electrical conductivity was considered to be caused by a decrease in the amount of solute iron, which requires holding the material at a high temperature for longer than several minutes.

Rotary properties of hybrid F1-ATPases consisting of subunits from different species.

F1-ATPase (F1) is an ATP-driven rotary motor protein ubiquitously found in many species as the catalytic portion of FoF1-ATP synthase. Despite the highly conserved amino acid sequence of the catalytic core subunits: α and ß, F1 shows diversity in the maximum catalytic turnover rate Vmax and the number of rotary steps per turn. To study the design principle of F1, we prepared eight hybrid F1s composed of subunits from two of three genuine F1s: thermophilic Bacillus PS3 (TF1), bovine mitochondria (bMF1), and Paracoccus denitrificans (PdF1), differing in the Vmax and the number of rotary steps. The Vmax of the hybrids can be well fitted by a quadratic model highlighting the dominant roles of ß and the couplings between α-ß. Although there exist no simple rules on which subunit dominantly determines the number of steps, our findings show that the stepping behavior is characterized by the combination of all subunits.

Molecular mechanism on forcible ejection of ATPase inhibitory factor 1 from mitochondrial ATP synthase.

IF1 is a natural inhibitor protein for mitochondrial FoF1 ATP synthase that blocks catalysis and rotation of the F1 by deeply inserting its N-terminal helices into F1. A unique feature of IF1 is condition-dependent inhibition; although IF1 inhibits ATP hydrolysis by F1, IF1 inhibition is relieved under ATP synthesis conditions. To elucidate this condition-dependent inhibition mechanism, we have performed single-molecule manipulation experiments on IF1-inhibited bovine mitochondrial F1 (bMF1). The results show that IF1-inhibited F1 is efficiently activated only when F1 is rotated in the clockwise (ATP synthesis) direction, but not in the counterclockwise direction. The observed rotational-direction-dependent activation explains the condition-dependent mechanism of IF1 inhibition. Investigation of mutant IF1 with N-terminal truncations shows that the interaction with the γ subunit at the N-terminal regions is crucial for rotational-direction-dependent ejection, and the middle long helix is responsible for the inhibition of F1.