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The multimolecular assembly of three-dimensionally structured proteins forms their quaternary structures, some of which have high geometric symmetry. The size and complexity of protein quaternary structures often increase in a hierarchical manner, with simpler, smaller structures serving as units for larger quaternary structures. In this study, we exploited oligomerization of a ribozyme cyclic trimer to achieve larger ribozyme-based RNA assembly. By installing kissing loop (KL) interacting units to one-, two-, or three-unit RNA molecules in the ribozyme trimer, we constructed dimers, open-chain oligomers, and branched oligomers of ribozyme trimer units. One type of open-chain oligomer preferentially formed a closed tetramer containing 12 component RNAs to provide 12 ribozyme units. We also observed large assembly of ribozyme trimers, which reached 1000 nm in size.

Naturally occurring ribozymes with a modular architecture are promising platforms for construction of RNA nanostructures because modular redesign enables their oligomerization. The resulting RNA nanostructures can exhibit the catalytic function of the parent ribozyme in an assembly dependent manner. In this study, we designed and constructed open-form oligomers of a bimolecular form of an RNase P ribozyme. The ribozyme oligomers were analyzed biochemically and by atomic force microscopy (AFM).

The micrometer-scale assembly of various DNA nanostructures is one of the major challenges for further progress in DNA nanotechnology. Programmed patterns of 1D and 2D DNA origami assembly using specific DNA strands and micrometer-sized lattice assembly using cross-shaped DNA origami were performed on a lipid bilayer surface. During the diffusion of DNA origami on the membrane surface, the formation of lattices and their rearrangement in real-time were observed using high-speed atomic force microscopy (HS-AFM). The formed lattices were used to further assemble DNA origami tiles into their cavities. Various patterns of lattice–tile complexes were created by changing the interactions between the lattice and tiles. For the control of the nanostructure formation, the photo-controlled assembly and disassembly of DNA origami were performed reversibly, and dynamic assembly and disassembly were observed on a lipid bilayer surface using HS-AFM. Using a lipid bilayer for DNA origami assembly, it is possible to perform a hierarchical assembly of multiple DNA origami nanostructures, such as the integration of functional components into a frame architecture.

Background and Objectives: Since spontaneous uterine rupture in the mid-trimester is rare, maternal and fetal outcomes in subsequent pregnancies remain unclear. Therefore, this study aimed to examine the maternal and fetal outcomes of subsequent pregnancies after prior mid-trimester uterine rupture. Materials and Methods: A systematic review using PubMed, the Cochrane Central Register of Controlled Trials, and Scopus until 30 September 2021, was conducted in compliance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The studies that clarified the maternal and fetal outcomes after prior mid-trimester uterine rupture and our case (n = 1) were included in the analysis. Results: Among the eligible cases, there were five women with eight subsequent pregnancies after prior mid-trimester uterine rupture. The timing of prior mid-trimester uterine rupture ranged from 15 to 26 weeks of gestation. The gestational age at delivery in subsequent pregnancies was 23–38 gestational weeks. Among the included cases (n = 8), those involving prior mid-trimester uterine rupture appeared to be associated with an increased prevalence of placenta accreta spectrum (PAS) (n = 3, 37.5%) compared with those involving term uterine rupture published in the literature; moreover, one case exhibited recurrent uterine rupture at 23 weeks of gestation (12.5%). No maternal deaths have been reported in subsequent pregnancies following prior mid-trimester uterine rupture. Fetal outcomes were feasible, except for one pregnancy with recurrent mid-trimester uterine rupture at 23 weeks of gestation, whose fetus was alive complicated by cerebral palsy. Conclusions: Our findings suggest that clinicians should be aware of the possibility of PAS and possible uterine rupture in pregnancies after prior mid-trimester uterine rupture. Further case studies are warranted to assess maternal and fetal outcomes in pregnancies following prior mid-trimester prior uterine rupture.

Background: Fetal ovarian cysts are the most frequently diagnosed intra-abdominal cysts; however, the evidence for perinatal management remains controversial. Methods: We retrospectively reviewed cases of fetal ovarian cysts diagnosed by prenatal ultrasonography at our institution between January 2010 and January 2020. The following were investigated: gestational age at diagnosis, cyst size, appearance, prenatal ultrasound findings, and postnatal outcomes. Prior to 2018, expectant management was applied in all cases; after 2018, in utero aspiration (IUA) of simple cysts ≥40 mm was performed. Results: We diagnosed 29 and seven simple and complex cysts, respectively. Fourteen patients had simple cysts with a maximum diameter

Ribozymes are catalytic RNAs that are attractive platforms for the construction of nanoscale objects with biological functions. We designed a dimeric form of the Tetrahymena group I ribozyme as a unit structure in which two ribozymes were connected in a tail-to-tail manner with a linker element. We introduced a kink-turn motif as a bent linker element of the ribozyme dimer to design a closed trimer with a triangular shape. The oligomeric states of the resulting ribozyme dimers (kUrds) were analyzed biochemically and observed directly by atomic force microscopy (AFM). Formation of kUrd oligomers also triggered trans-splicing reactions, which could be monitored with a reporter system to yield a fluorescent RNA aptamer as the trans-splicing product.

Women born between 1994 and 1999 achieved high vaccination rates for human papillomavirus (HPV); they are now reaching the age of cervical cancer screening programs in Japan. In this study, we aimed to investigate the health awareness of HPV-vaccinated and unvaccinated women and to create tailored leaflets recommending cervical cancer screening for each. Surveys on the cancer screening rates for HPV-vaccinated and unvaccinated women aged 20 and 21 have demonstrated that the rate was significantly higher (p < 0.01) in vaccinated (6.2%) than in unvaccinated women (3.1%). Next, interviews and Internet questionnaires clarified that there was a trend that vaccinated women have a better health consciousness than the unvaccinated ones, and that in unvaccinated women, their willingness to receive cervical cancer screening was significantly enhanced by the fear of developing cancer. Finally, in a prospective study, the increase in the screening rate for both vaccinated and unvaccinated groups after they read tailored leaflets, from 6.4% to 7.4% and from 3.9% to 5.1%, respectively, was not statistically significant compared to the groups provided with a standard reminder letter. Cervical cancer control measures might be enhanced by recommending cervical cancer screening in ways better tailored to HPV vaccination status.

Pelvic organ prolapse (POP) can occur if the support tissues or the pelvic floor muscles are weakened and damaged. There is increased probability for POP occurrence after childbirth, menopause, or in overweight women. Because the natural history and progression of POP is still unknown, the approaches used to prevent it have not been clear. POP is an uncomfortable condition that affects one every three women. However, most people feel uncomfortable to discuss it. Herein, we conducted a feasibility evaluation study for self-assessment approaches with a vaginal endoscope based on three-dimensional (3D) printing. The proposed endoscope has two parts: (a) rubber material used to cover it for its intended insertion, to avoid direct contact with the walls of the vagina, and (b) two types of sensors at the tip for measurements. The condition inside the vagina was observed with a camera and depth sensors based on the regulation of the amount of air. Arbitrary temporary prolapses from the testbed’s generator enabled us to perceive the location of the problem and symptoms that were regarded as the early stage. As discussed, the low-cost design of the 3D-printed-based vaginal endoscope provides a self-check capability and allows continuous observations that help prevent POP.

Preeclampsia, a systemic vascular disorder characterized by new-onset hypertension and proteinuria after 20 weeks of gestation, is the leading cause of maternal and perinatal morbidity and mortality. Maternal endothelial dysfunction caused by placental factors has long been accepted with respect to the pathophysiology of preeclampsia. Over the past decade, increased production of placental antiangiogenic factors has been identified as a placental factor leading to maternal endothelial dysfunction and systemic vascular dysfunction. This review summarizes the recent advances in understanding the molecular mechanisms of endothelial dysfunction caused by placental antiangiogenic factors, and the novel clinical strategies based on these discoveries.

DNA can assemble various molecules and nanomaterials in a programmed fashion and is a powerful tool in the nanotechnology and biology research fields. DNA also allows the construction of desired nanoscale structures via the design of DNA sequences. Structural nanotechnology, especially DNA origami, is widely used to design and create functionalized nanostructures and devices. In addition, DNA molecular machines have been created and are operated by specific DNA strands and external stimuli to perform linear, rotational, and reciprocating movements. Furthermore, complicated molecular systems have been created on DNA nanostructures by arranging multiple molecules and molecular machines precisely to mimic biological systems. Currently, DNA nanomachines, such as molecular motors, are operated on DNA nanostructures. Dynamic DNA nanostructures that have a mechanically controllable system have also been developed. In this review, we describe recent research on new DNA nanomachines and nanosystems that were built on designed DNA nanostructures.

Tadalafil is a phosphodiesterase 5 (PDE5) inhibitor with a long half-life, high selectivity, and rapid onset of action. Because the safety of using PDE5 inhibitors as therapeutic agents for fetal growth restriction (FGR) has been a problem worldwide, this paper primarily focuses on the safety assessments performed in the Tadalafil Treatment for Fetuses with Early-Onset Growth Restriction (TADAFER) II population. Neonatal and maternal adverse events were analyzed, in addition to fetal, neonatal, and infant death cases, six months after stopping the trial. Eighty-nine pregnant women with FGR were studied between September 2016 and March 2018 (45 and 44 in the tadalafil and conventional treatment groups, respectively). Seven (16%) deaths (four fetal, one neonatal, and two infant) in the control group, whereas only one neonatal death occurred in the tadalafil group. Although headache, facial flushing, and nasal hemorrhage occurred more frequently in the tadalafil group, these symptoms were Grade 1 and transient. In conclusion, this trial showed that tadalafil decreased the fetal and infant deaths associated with FGR. This is thought to be primarily due to pregnancy prolongation. Further studies are warranted to evaluate the efficacy of tadalafil in treating early-onset FGR.