Publications by authors named "S Hirokawa"

Background: The copy number status (CNS) of the survival motor neuron (SMN) gene may influence the risk and prognosis of amyotrophic lateral sclerosis (ALS) and lower motor neuron diseases (LMND) other than spinal muscular atrophy (SMA). However, previous studies of this association, mainly from Europe, have yielded controversial results, suggesting possible regional differences. Here, we investigated the effect of the SMN gene in Japanese patients with ALS and LMND.

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Motor-driven cytoskeletal remodeling in cellular systems can often be accompanied by a diffusive-like effect at local scales, but distinguishing the contributions of the ordering process, such as active contraction of a network, from this active diffusion is difficult to achieve. Using light-dimerizable kinesin motors to spatially control the formation and contraction of a microtubule network, we deliberately photobleach a grid pattern onto the filament network serving as a transient and dynamic coordinate system to observe the deformation and translation of the remaining fluorescent squares of microtubules. We find that the network contracts at a rate set by motor speed but is accompanied by a diffusive-like spread throughout the bulk of the contracting network with effective diffusion constant two orders of magnitude lower than that for a freely-diffusing microtubule.

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Inhibition of autophagy is an important strategy in cancer therapy. However, prolonged inhibition of certain autophagies in established cancer cells may increase therapeutic resistance, though the underlying mechanisms of its induction and enhancement remain unclear. This study sought to elucidate the mechanisms of therapeutic resistance through repeated autophagy inhibition and amino acid deprivation (AD) in an in vitro model of in vivo chronic nutrient deprivation associated with cancer cell treatment.

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Article Synopsis
  • The study evaluates whether annual fecal immunochemical tests (FIT) are necessary for patients who recently had a total colonoscopy (TCS) in Japan, as current guidelines recommend annual FIT screening but lack consensus for these patients.
  • Researchers analyzed data from 671 patients with positive FIT results, dividing them into those who had a TCS within the past 5 years and those who had not, and found that those with recent TCS had significantly lower rates of advanced neoplasia (4.6% vs. 12.1%).
  • The conclusion suggests that patients with adenomatous lesions should follow their surveillance program with repeat TCS instead of annual FIT, while the necessity of annual FIT
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Endoscopic ultrasound (EUS)-guided transhepatic biliary drainage is usually performed with a 19-gauge fine-needle aspiration (FNA) needle and a 0.025-inch guidewire. The combination of a 22-gauge FNA needle and a 0.

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