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At the angle of the mouth, spoke‐like muscle bundles converge at the "modiolus," which is believed to appear in utero. The aim of this study was to investigate the growth of the modiolus histologically. We studied frontal histological sections of the face from 12 midterm and six near‐term fetuses. At midterm, a convergence of the levator anguli oris (LAOM) and depressor anguli oris (DAOM) was frequently present, and another convergence of the LAOM with the platysma (PM) or orbicularis oris (OOM) was also often evident. At near‐term, muscle fiber merging or interdigitation was classified into nine combinations, five of which were frequently seen: LAOM‐PM, LAOM‐DAOM, zygomaticus major (ZMM)‐orbicularis oris (OOM), buccinator (BM)‐LAOM, and BM‐PM. These combinations existed at slightly different depths and/or sites, thus allowing the angle of the mouth to receive multiple muscles. Notably, tissues interposed between the muscle fibers were limited to a thin epimysium at each crossing or interdigitation. Therefore, the LAOM, DAOM, OOM, BM, and PM appear to form a basic configuration at birth, but the development and growth were much delayed than the classical description. The modiolus is not a specific fibromuscular structure but simply represents a cluster of muscle convergence sites. Even at meeting between an elevator and depressor, a specific fibrous structure seems unlikely to connect the epimysium for the muscle convergence. Instead, the central nervous system appears to regulate the activity of related muscles to minimize tension or friction stress at the meeting site. [ABSTRACT FROM AUTHOR]

The complete nucleotide sequence of the chloroplast genome of sugarcane (Saccharum offcinarum) has been determined. It is a circular double-stranded DNA molecule, 141,182 bp in size, and is composed of a large single copy of 83,048 bp, a small single copy of 12,544 bp, and a pair of inverted repeat regions of 22,795 bp each. A comparative analysis among monocots showed that the sugarcane chloroplast genome was very similar to maize but not to rice or wheat. Between sugarcane and maize at the rps16–trnQ (UUG) region, however, a length polymorphism was identified. With regard to insertions/deletions equal to or longer than 5 bp, a total of 53 insertion and 31 deletion events were identified in the sugarcane chloroplast genome. Of the 84 loci identified, a pair of direct repeat sequences was located side by side in a tandem fashion in 47 loci (56.0%). A recombination event during plant evolution is discussed at two sites between the sugarcane and tobacco chloroplast genomes. [ABSTRACT FROM PUBLISHER]

Here we report the cloning of a sucrose transporter cDNA from maize (Zea mays L.) and an analysis of the expression of the gene. A cDNA clone (ZmSUT1) was identified as a sucrose transporter cDNA from its sequence homology at the amino acid level to sucrose transporters that have been cloned from other higher plant species. Based on the results of genomic Southern hybridization, ZmSUT1 appears to be a single copy gene. A Northern blot analysis of seedlings and leaf blades suggests that the sucrose transporter is involved in the export of accumulated carbohydrates from source leaf blades. From the measurements of transcript levels and carbohydrate contents in mature leaf blades, we propose that the expression of the gene for the maize sucrose transporter is positively regulated by the amounts of soluble sugars such as sucrose arid glucose in source leaves of maize. In addition, based on the tissue specificity of the expression of the gene in maize plants at the reproductive stage, it is possible that the sucrose transporter acts in sink tissues such as pedicels as well as in source tissues such as leaf blades. [ABSTRACT FROM AUTHOR]

A novel class of potent Na V 1.7 inhibitors has been discovered. The replacement of diaryl ether in compound I was investigated to enhance mouse Na V 1.7 inhibitory activity, which resulted in the discovery of N -aryl indoles. The introduction of the 3-methyl group is crucial for high Na V 1.7 in vitro potency. The adjustment of lipophilicity led to the discovery of 2e . Compound 2e (DS43260857) demonstrated high in vitro potencies against both human and mouse Na V 1.7 with high selectivity over Na V 1.1, Na V 1.5, and hERG. In vivo evaluations revealed 2e demonstrating potent efficacy in PSL mice with excellent pharmacokinetics., Competing Interests: The authors declare no competing financial interest., (© 2023 American Chemical Society.)

A highly potent, selective Na V 1.7 inhibitor, DS-1971a, has been discovered. Exploration of the left-hand phenyl ring of sulfonamide derivatives ( I and II ) led to the discovery of novel series of cycloalkane derivatives with high Na V 1.7 inhibitory potency in vitro. As the right-hand heteroaromatic ring affected the mechanism-based inhibition liability of CYP3A4, replacement of this moiety resulted in the generation of 4-pyrimidyl derivatives. Additionally, GSH adducts formation, which can cause idiosyncratic drug toxicity, was successfully avoided by this modification. An additional optimization led to the discovery of DS-1971a. In preclinical studies, DS-1971a demonstrated highly potent selective in vitro profile with robust efficacy in vivo. DS-1971a exhibited a favorable toxicological profile, which enabled multiple-dose studies of up to 600 mg bid or 400 mg tid (1200 mg/day) administered for 14 days to healthy human males. DS-1971a is expected to exert potent efficacy in patients with peripheral neuropathic pain, with a favorable safety profile.