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Purpose: To determine the rates of trial of labor after cesarean delivery (TOLAC) and complications in Japan.Methods: We conducted a descriptive study of pregnant women with one prior cesarean section registered between January 2013 and December 2015 in the perinatal database of the Japan Society of Obstetrics and Gynecology. This database is a nationwide institution-based registry in Japan. This study included women who had undergone one prior cesarean delivery and who delivered a singleton by cephalic presentation between 37 and 41 weeks of gestation. We collected data on delivery method, particularly with regard to the involvement of TOLAC or elective repeated cesarean deliveries (ERCD). Rates of TOLAC were investigated by facility type, and we calculated the rates of maternal and perinatal complications including uterine rupture in TOLAC.Results: During the study period, 647,098 births were registered. Among the 34,460 women who met the inclusion criteria, 1730 (5.0%) and 32,730 (95.0%) underwent TOLAC and ERCD, respectively. In total, 76.4% of hospitals did not perform TOLAC at all. Generally in perinatal medical centers, which are better equipped with facilities, 58.7% women did not perform TOLAC. With regard to complications, we identified eight cases (0.46%) of uterine rupture with TOLAC. TOLAC births did not include maternal death and perinatal death. Among women attempting TOLAC, 1532 (88.6%) had successful vaginal births.Conclusion: The TOLAC rate in Japan was considerably lower than that reported in other countries, despite comparable complication rates. [ABSTRACT FROM AUTHOR]

Highlights: [•] The N-terminal 1–83 residues of apoA-I have a propensity to form amyloid fibrils. [•] ApoA-I 1–43 peptide forms amyloid fibrils with transition to β-sheet-rich structure. [•] The G26R point mutation enhances the fibril formation of apoA-I 1–43 peptide. [•] The extreme N-terminal region plays a crucial role in fibril formation by apoA-I. [ABSTRACT FROM AUTHOR]

A number of naturally occurring mutations of apolipoprotein (apo) A-I, the major protein of HDL, are known to be associated with hereditary amyloidosis and atherosclerosis. Here, we examined the effects of the G26R point mutation in apoA-I (apoA-IIowa) on the structure, stability, and aggregation propensity to form amyloid fibril of full-length apoA-I and the N-terminal fragment of apoA-I. Circular dichroism and fluorescence measurements demonstrated that the G26R mutation destabilizes the N-terminal helix bundle domain of full-length protein, leading to increased hydrophobic surface exposure, whereas it has no effect on the initial structure of the N-terminal 1-83 fragment, which is predominantly a random coil structure. Upon incubation for extended periods at neutral pH, the N-terminal 1-83 variants undergo a conformational change to β-sheet-rich structure with a great increase in thioflavin T fluorescence, whereas no structural change is observed in fulllength proteins. Comparison of fibril-forming propensity among substituted mutants at Gly-26 position of 1-83 fragments demonstrated that the G26R mutation enhances the nucleation step of fibril formation, whereas G26K and G26E mutations have small or inhibiting effects on the formation of fibrils. These fibrils of the 1-83 variants have long and straight morphology as revealed by atomic force microscopy and exhibited significant toxicity with HEK293 cells. Our results indicate dual critical roles of the arginine residue at position 26 in apoAIIowa: destabilization of the N-terminal helix bundle structure in full-length protein and enhancement of amyloid fibril formation by the N-terminal 1-83 fragment. [ABSTRACT FROM AUTHOR]

Objective: The purpose of this study was to compare surgical outcomes following conventional laparoscopic hysterectomy (LH) (C-LH) versus the combination method of LH plus laparoscopic myomectomy (LM) (LH+LM) for the treatment of large uterine fibroids.Study Design: This study was performed in 56 patients (uterine weights ≥500g) who underwent either C-LH or LH+LM performed by the same surgeon between May 2010 and May 2016. LH+LM was performed when C-LH was problematic because of poor visibility and/or mobility due to uterine fibroids.Results: The C-LH and LH+LM groups consisted of 27 (48%) and 29 (52%) patients, respectively. The clinical characteristics of patients differed significantly only in the median sizes of the dominant fibroid. The sizes of the dominant fibroid in the C-LH and LH+LM groups were 9.5cm and 10.7cm (P=0.04), respectively. Regarding the surgical outcomes for the C-LH and LH+LM groups, the median uterine weights were 558g and 737g (P=0.03), respectively, the median operating times were 156min and 173min (P=0.23), respectively, and the median intraoperative blood losses were 150g and 300g (P=0.0004), respectively. In all patients, LH was performed without conversion to laparotomy and there were no cases of bladder, ureteral, or gastrointestinal tract injury. There were no postoperative complications of Clavien-Dindo scale≥III in either group.Conclusions: When C-LH cannot be performed because of large uterine fibroids that cause poor visibility and/or mobility, LH+LM may allow the procedure to be successfully completed without conversion to laparotomy. However, the latter approach increases the risk for intraoperative blood loss. [ABSTRACT FROM AUTHOR]

The binding of monomeric and aggregated variants of 1-83 N-terminal fragment of apolipoprotein A-I with substitution mutations G26R, G26R/W@8, G26R/W@50 and G26R/W@72 to the model lipid membranes composed of phosphatidylcholine and its mixture with cholesterol has been investigated using fluorescent probes pyrene and Laurdan. Examination of pyrene spectral behavior did not reveal any marked influence of apoA-I mutants on the hydrocarbon region of lipid bilayer. In contrast, probing the membrane effects by Laurdan revealed decrease in the probe generalized polarization in the presence of aggregated proteins. suggesting that oligomeric and fibrillar apoA-I species induce increase in hydration degree and reduction of lipid packing density in the membrane interfacial region. These findings may shed light on molecular details of amyloid cytotoxicity. [ABSTRACT FROM AUTHOR]

Apolipoprotein A-I is amenable to a number of specific mutations associated with hereditary systemic amyloidoses. Amyloidogenic properties of apoA-I are determined mainly by its N-terminal fragment. In the present study Förster resonance energy transfer between tryptophan as a donor and Thioflavin T as an acceptor was employed to obtain structural information on the amyloid fibrils formed by apoA-I variant 1-83/G26R/W@8. Analysis of the dye-fibril binding data provided evidence for the presence of two types of ThT binding sites with similar stoichiometries (bound dye to monomeric protein molar ratio ∼10), but different association constants (∼6 and 0.1μM−1) and ThT quantum yields in fibril-associated state (0.08 and 0.05, respectively). A β-strand–loop–β-strand structural model of 1-83/G26R/W@8 apoA-I fibrils has been proposed, with potential ThT binding sites located in the solvent-exposed grooves of the N-terminal β-sheet layer. Reasoning from the expanded FRET analysis allowing for heterogeneity of ThT binding centers and fibril polymorphism, the most probable locations of high- and low-affinity ThT binding sites were attributed to the grooves T16_Y18 and D20_L22, respectively. [ABSTRACT FROM AUTHOR]

A terahertz linear polarizer was developed with a single crystal of methyl 4-nitrobenzoate. Several IR-active vibrations with parallel moments of transition were concentrated in a frequency range around 2.7 THz. These results establish a new category of polarizers. [Display omitted] • A terahertz linear polarizer was made of an organic single crystal. • A single crystal of methyl 4-nitrobenzoate has clear anisotropy. • The anisotropy is mainly due to one or two parallel fundamental modes. • The same strategy will allow the development of higher quality polarizers. A terahertz linear polarizer was developed using a single crystal of methyl 4-nitrobenzoate. Flat molecules are arranged in parallel in the crystal and the intramolecular vibrations efficiently absorb terahertz waves with high anisotropy. Several infrared-active intramolecular vibrations with parallel moments of transition concentrate in a frequency band between 2.2 and 3.2 THz. The highest degree of polarization of 76% was achieved at 2.74 THz (T max = 80%, T min = 11%). This result establishes a new category of polarizer that can be manufactured in a simple process at low cost. [ABSTRACT FROM AUTHOR]

Nonadecane, normal alkane C 19 H 40 , has an orientationally disordered phase (rotator phase) between the melting point (305 K) and the transition temperature (293 K). The phase transition from the disordered phase to the ordered phase during the cooling process beyond the transition temperature was simulated based on the rate equation focusing on the state of molecules rotating or fixed. An experimental time profile curve of the disordered-ordered phase transition progression obtained by terahertz spectroscopy was reproduced successfully, allowing visualization of the transition and the formation of orientational domain structures in computer simulations. [ABSTRACT FROM AUTHOR]