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Actin is well known for its cytoskeletal functions, where it helps to control and maintain cell shape and architecture, as well as regulating cell migration and intracellular cargo transport, among others. However, actin is also prevalent in the nucleus, where genome-regulating roles have been described, including it being part of chromatin-remodeling complexes. More recently, with the help of advances in microscopy techniques and specialized imaging probes, direct visualization of nuclear actin filament dynamics has helped elucidate new roles for nuclear actin, such as in cell cycle regulation, DNA replication and repair, chromatin organization and transcriptional condensate formation. In this Cell Science at a Glance article, we summarize the known signaling events driving the dynamic assembly of actin into filaments of various structures within the nuclear compartment for essential genome functions. Additionally, we highlight the physiological role of nuclear F-actin in meiosis and early embryonic development. [ABSTRACT FROM AUTHOR]

Study Design: Cross-sectional observational study. Purpose: To examine whether pelvic rotation as a compensatory mechanism for sagittal imbalance is related to quality of life (QOL). Overview of Literature: Poor sagittal alignment is associated with compensatory pelvic retroversion and decreased QOL. Whether the compensatory pelvic tilt (PT) influences QOL is unclear. Methods: Overall, 134 subjects aged ≥20 years with lower back pain were included (104 females; mean age, 70±9.8 years). Sagittal vertical alignment (SVA) and PT were analyzed radiographically. Patients were stratified into three groups based on SVA values: good alignment (group G), intermediate alignment (group I), and poor sagittal alignment (group P). Patients in group I were further categorized into two groups: low PT and high PT. The Japanese Orthopaedic Association Back Pain Evaluation Questionnaire (JOABPEQ) was used for clinical assessment, and the scores were compared between groups. Results: As SVA increased, PT and lumbar lordosis (LL) increased and decreased, respectively. PT and LL differed significantly between groups G and P (p <0.01 for each comparison). Within group I, there was no significant difference in SVA between the high PT and low PT groups, suggesting that the high PT group had acquired a compensated sagittal balance. Importantly, all domains in the JOABPEQ (except for lower back pain) were significantly lower in the high PT group than in the low PT group (p <0.05 for every comparison). Conclusions: This study showed that focusing solely on SVA as a single indicator can cause important losses in QOL to be overlooked in patients with lumbar disorders. Although pelvic retroversion can compensate for sagittal balance, it is associated with a significant decrease in QOL. To improve the assessment of patients with lumbar disorders, PT should be considered besides SVA. [ABSTRACT FROM AUTHOR]

Multicellular organisms consist of multiple cell types. The identity of these cells is primarily maintained by cell-type-specific gene expression programs; however, mechanisms that suppress these programs are poorly defined. Here we show that serum response factor (Srf), a transcription factor that is activated by various extracellular stimuli, can repress cell-typespecific genes and promote cellular reprogramming to pluripotency. Manipulations that decrease β-actin monomer quantity result in the nuclear accumulation of Mkl1 and the activation of Srf, which downregulate cell-type-specific genes and alter the epigenetics of regulatory regions and chromatin organization. Mice overexpressing Srf exhibit various pathologies including an ulcerative colitis-like symptom and a metaplasia-like phenotype in the pancreas. Our results demonstrate an unexpected function of Srf via a mechanism by which extracellular stimuli actively destabilize cell identity and suggest Srf involvement in a wide range of diseases. [ABSTRACT FROM AUTHOR]

The rarely caught grenadier, Coelorinchus sheni Chiou, Shao and Iwamoto, 2004, is newly recorded from Japanese waters, based on a single specimen (196 mm in head length, 692+ mm in total length) collected from the East China Sea off the north-west coast of Ie-jima island, Okinawa, at a depth of 650 m. It belongs to the C. tokiensis group, and readily differs from other Japanese congeners in having a series of dark saddles on the body, a fully-scaled underside of the head, and a short light organ anterior to the anus (its anterior tip falling far short of a line connecting the inner pelvic-fin bases), and in lacking a complete bony support of the lateral nasal ridge. The morphology of the Japanese specimen is fully described, with the first report of the species' fresh coloration. Localities of type specimens of C. sheni are also emended. Coelorinchus sheni was previously known only from Taiwan; thus the Japanese specimen represents the first record of the species from outside Taiwanese waters and the northernmost record of the species. [ABSTRACT FROM AUTHOR]

Study Design: Retrospective study. Purpose: The purpose of this study was to investigate the influence of sagittal alignment of the strut graft on graft subsidence and clinical outcomes after anterior cervical corpectomy and fusion (ACCF). Overview of Literature: ACCF is a common technique for the treatment of various cervical pathologies. Although graft subsidence sometimes occurs after ACCF, it is one cause for poor clinical results. Malalignment of the strut graft is probably one of the factors associated with graft subsidence. However, to the best of our knowledge, no prior reports have demonstrated correlations between the alignment of the strut graft and clinical outcomes. Methods: We evaluated 56 patients (33 men and 23 women; mean age, 59 years; range, 33-84 years; 45 with cervical spondylotic myelopathy and 11 with ossification of the posterior longitudinal ligament) who underwent one-or two-level ACCF with an autogenous fibular strut graft and anterior plating. The Japanese Orthopaedic Association (JOA) score recovery ratio for cervical spondylotic myelopathy was used to evaluate clinical outcomes. The JOA score and lateral radiograms were evaluated 1 week and 1 year postoperatively. Patients were divided into two groups (a straight group [group I] and an oblique group [group Z]) based on radiographic assessment of the sagittal alignment of the strut graft. Results: Group I showed a significantly greater JOA score recovery ratio (p<0.05) and a significantly lower graft subsidence than group Z (p<0.01). Conclusions: Our findings suggest that a straight alignment of the strut graft provides better clinical outcomes and lower incidence of graft subsidence after ACCF. In contrast, an oblique strut graft can lead to significantly increased strut graft subsidence and poor clinical results. [ABSTRACT FROM AUTHOR]

An old museum specimen of the rare deep-sea species Ophichthus exourus McCosker, 1999 (Anguilliformes: Ophichthidae) (685 mm in total length) collected near Saipan and a recently collected example from Okinawa, Japan (634 mm in total length) represent the first Northern Hemisphere records of the species, previously known only from the southwestern Pacific in waters off New Caledonia and Fiji, but now believed to be widely distributed in the western Pacific Ocean. A detailed morphological observation based on the above specimens and a re-examination of the holotype resulted in a revision of some species characteristics, including the number of infraorbital pores. Ophichthus exourus is distinguished from other congeners by the following combination of characters: head 8.3-10.0% of total length; upper jaw 36.1-38.1% of head length; pectoral-fin rounded, length 19.2-24.1% of head length; rear margin of eye above or slightly behind rictus; eye diameter 44.4-61.2% of snout length; horizontal length of posterior nostril dermal flap much greater than diameter of anterior nostril tube; gill opening to dorsal-fin origin greater than twice pectoral-fin length; preopercular pores 2; predorsal and total vertebrae 20-21 and 173-177, respectively; lower-jaw teeth nearly uniserial; body without bands or spots; posteriormost portion (much shorter than head length) of anal-fin membrane indistinct darkish brown. A new standard Japanese name "Gunbai-umihebi" is proposed for the species. [ABSTRACT FROM AUTHOR]

Actin is a highly abundant protein in eukaryotic cells and dynamically changes its polymerized states with the help of actin-binding proteins. Its critical function as a constituent of cytoskeleton has been well-documented. Growing evidence demonstrates that actin is also present in nuclei, referred to as nuclear actin, and is involved in a number of nuclear processes, including transcriptional regulation and chromatin remodeling. The contribution of nuclear actin to transcriptional regulation can be explained by its direct interaction with transcription machineries and chromatin remodeling factors and by controlling the activities of transcription factors. In both cases, polymerized states of nuclear actin affect the transcriptional outcome. Nuclear actin also plays an important role in activating strongly silenced genes in somatic cells for transcriptional reprogramming. When these nuclear functions of actin are considered, it is plausible to speculate that nuclear actin is also implicated in embryonic development, in which numerous genes need to be activated in a well-coordinated manner. In this review, we especially focus on nuclear actin's roles in transcriptional activation, reprogramming and development, including stem cell differentiation and we discuss how nuclear actin can be an important player in development and cell differentiation. [ABSTRACT FROM AUTHOR]

Study Design: Retrospective study. Purpose: To assess treatment outcomes of snowboarding-related spinal and spinal cord injuries. Overview of Literature: Snowboarding-related spinal or spinal cord injury have a great impact on social and sporting activities. Methods: A retrospective review of 19 cases of surgically treated snowboard-related injury was done. Analyzed parameters included site of injury, type of fracture, peri- and postoperative complications, pre- and postoperative neurological status, activities of daily living, and participation in sports activities at the final follow-up. Results: The major site of injury was the thoracolumbar junction caused by fracture-dislocation (13/19 cases). The remaining 6 cases had cervical spine injuries. Over 60% of the patients had Frankel A and B paralysis. All patients were surgically treated by posterior fusion with instrumentation. Five underwent additional anterior fusion. Surgical outcome was restoration of ambulatory capacity in 12 patients (63.2%). Ultimately, 15 patients (78.9%) could return to work. Patients with complete paralysis upon admission showed reduced ambulatory capacity compared to those with incomplete paralysis. None of the patients again participated in any sports activities, including snowboarding. Conclusions: Snowboarding-related spinal or spinal cord injury has a great impact on social as well as sports activities. It is necessary to enhance promotion of injury prevention emphasizing the snowboarders' responsibility code. [ABSTRACT FROM AUTHOR]