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A conjugated polymer nanowire can be created at any designated position in a monomolecular layer by initiating chain polymerization using a scanning tunneling microscope tip with a spatial precision of the order of 1 nm. The demonstration has been presented for a self-ordered monomolecular layer of 10,12-pentacosadiynoic acid, which is a diacetylene compound, adsorbed on a graphite surface. The polymer nanowires created have a length ranging from 5 to 300 nm, the length being controlled by domain boundaries or artificial defects in the molecular layer. The frequency of occurrence of chain polymerization is measured against the pulsed bias voltage, which suggests that the excitation of the molecule is caused by the inelastically tunneling electrons. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR] more...

Background and Purpose: Hydrogen sulfide (H(2) S), generated by enzymes such as cystathionine-γ-lyase (CSE) from L-cysteine, facilitates pain signals by activating the Ca(v) 3.2 T-type Ca(2+) channels. Here, we assessed the involvement of the CSE/H(2) S/Ca(v) 3.2 pathway in cystitis-related bladder pain.Experimental Approach: Cystitis was induced by i.p. administration of cyclophosphamide in mice. Bladder pain-like nociceptive behaviour was observed and referred hyperalgesia was evaluated using von Frey filaments. Phosphorylation of ERK in the spinal dorsal horn was determined immunohistochemically following intravesical administration of NaHS, an H(2) S donor.Key Results: Cyclophosphamide caused cystitis-related symptoms including increased bladder weight, accompanied by nociceptive changes (bladder pain-like nociceptive behaviour and referred hyperalgesia). Pretreatment with DL-propargylglycine, an inhibitor of CSE, abolished the nociceptive changes and partly prevented the increased bladder weight. CSE protein in the bladder was markedly up-regulated during development of cystitis. Mibefradil or NNC 55-0396, blockers of T-type Ca(2+) channels, administered after the symptoms of cystitis appeared, reversed the nociceptive changes. Further, silencing of Ca(v) 3.2 protein by repeated intrathecal administration of mouse Ca(v) 3.2-targeting antisense oligodeoxynucleotides also significantly attenuated the nociceptive changes, but not the increased bladder weight. Finally, the number of cells staining positive for phospho-ERK was increased in the superficial layer of the L6 spinal cord after intravesical administration of NaHS, an effect inhibited by NNC 55-0396.Conclusion and Implications: Endogenous H(2) S, generated by up-regulated CSE, caused bladder pain and referred hyperalgesia through the activation of Ca(v) 3.2 channels, one of the T-type Ca(2+) channels, in mice with cyclophosphamide-induced cystitis. [ABSTRACT FROM AUTHOR] more...

Background and Purpose: Hydrogen sulfide, a gasotransmitter, facilitates somatic pain signals via activation of Ca(v)3.2 T-type calcium channels in rats. Given evidence for the activation of transient receptor potential ankyrin-1 (TRPA1) channels by H(2)S, we asked whether TRPA1 channels, in addition to Ca(v)3.2 channels, contribute to the H(2)S-induced mechanical hyperalgesia and allodynia in mice.Experimental Approach: Mechanical hyperalgesia and allodynia were evaluated by the von Frey test in mice. Ca(v)3.2 or TRPA1 channels in the sensory neurons were silenced by repeated intrathecal administration of antisense oligodeoxynucleotides in mice.Key Results: Intraplantar administration of NaHS evoked hyperalgesia and allodynia in mice, an effect attenuated or abolished by NNC 55-0396 or mibefradil, T-type calcium channel blockers, and by ascorbic acid or zinc chloride, known to selectively inhibit Ca(v)3.2 channels, out of the three isoforms of T-type calcium channels. Silencing of Ca(v)3.2 channels in the sensory neurons also prevented the NaHS-induced hyperalgesia and allodynia in mice. The NaHS-induced hyperalgesia and allodynia in mice were significantly suppressed by AP18, a TRPA1 channel blocker, and by silencing of TRPA1 channels in the sensory neurons.Conclusions and Implications: Mechanical hyperalgesia and allodynia induced by NaHS/H(2)S required activation of both Ca(v)3.2 and TRPA1 channels in mice. [ABSTRACT FROM AUTHOR] more...

Analyzes the gel maturation behavior of aqueous gelatin using dynamic rheometry, optical rotation measurement and differential scanning calorimetry. Characteristics of gelatin; Effect of the degree of freedom in molecular motion near the cross-linking sites on the gel maturation process; Comparison of melting behavior for pre-matured and annealed gels. more...

Examines the characteristics of sol-gel transition of a mixture made by mixing two kinds of gelling agents of different nature. Characteristics of gelatin; Types of gelatin; Description of several preparation methods for gelatin and carrageenan; Effect of the quantity of κ-carrageenan level on the potential of hydrogen ions of gelatin and κ-carrageenan mixed solution. more...

Examines the use of chemical reactions in copper atom transportation from a tip of scanning tunneling microscope onto an argon(110) surface. Preparation of a copper coated tungsten tip; Observation of the growth of copper-oxygen rows on the surface; Reaction of copper atoms when vaporized over the surface. more...

Background: Gastric cancer is a major oncological challenge, ranking highly among causes of cancer-related mortality worldwide. This study was initiated to address the variability in patient responses to combination chemotherapy, highlighting the need for personalized treatment strategies based on genomic data., Methods: We analyzed whole-genome and RNA sequences from biopsy specimens of 65 advanced gastric cancer patients before their chemotherapy treatment. Using machine learning techniques, we developed a model with 123 omics features, such as immune signatures and copy number variations, to predict their chemotherapy outcomes., Results: The model demonstrated a prediction accuracy of 70-80% in forecasting chemotherapy responses in both test and validation cohorts. Notably, tumor-associated neutrophils emerged as significant predictors of treatment efficacy. Further single-cell analyses from cancer tissues revealed different neutrophil subgroups with potential antitumor activities suggesting their usefulness as biomarkers for treatment decisions., Conclusions: This study confirms the utility of machine learning in advancing personalized medicine for gastric cancer by identifying tumor-associated neutrophils and their subgroups as key indicators of chemotherapy response. These findings could lead to more tailored and effective treatment plans for patients., Competing Interests: Declarations. Conflict of interest: X. Peng: reports being a full-time employee of Precision Scientific (Beijing) Ltd. H. Liang: reports being an adviser of Precision Scientific (Beijing) Ltd. No disclosures were reported by the other authors. Ethics approval and consent to participate: Informed consent was obtained from all participants who were registered from January 2013 to December 2017. The study was approved by the institutional review boards of the National Cancer Center (2012–118) and RIKEN and registered with the University Hospital Medical Information Network Clinical Trials Registry (UMIN-CTR), number 000009564. Consent for publication: Not applicable., (© 2024. The Author(s).) more...

We have developed a rapid, simple, and high-throughput screening system for recombinant enzymes using disulfide-bonded hydrogel beads (HBs) produced via a microfluidic method. These redox-responsive HBs were compatible with the biosynthesis of enzyme mutants via cell-free protein synthesis, fluorescent staining through an enzymatic reaction, and genetic information recovery after fluorescence-activated droplet sorting (FADS). The expression of microbial transglutaminase zymogen (MTGz) using cell-free protein synthesis and the cross-linking-reactivity-based staining of HBs with a fluorescent product were validated. Next-generation sequencing (NGS) analysis of the genes recovered from highly fluorescent HBs identified novel mutation sites (N25 and N27) in the propeptide domain. The introduction of these mutations allowed for the design of an engineered active MTGz, demonstrating the potential of HBs as artificial compartments for the FADS-based selection of enzymes that catalyze peptide and protein cross-linking reactions. more...

Background/Objectives : Obesity is a risk factor for chronic kidney disease (CKD) in Asians. The Asia-Pacific body mass index (BMI) classification sets lower obesity cutoffs than the conventional BMI classification for all races, generally reflecting the lower BMIs in Asians. This longitudinal study evaluated the association between BMI, as classified by the Asia-Pacific BMI system, and CKD development in non-diabetic Asian adults. Methods : A population-based longitudinal study (1998-2023) was conducted in non-diabetic Japanese adults (hemoglobin A1c < 6.5%) in Zentsuji City (Kagawa Prefecture, Japan). The generalized gamma model was used to assess the relationship between time-varying BMI categories and CKD development, stratified by sex. CKD was defined as an estimated glomerular filtration rate of <60 mL/min/1.73 m 2 . BMI was calculated as weight (kg) divided by the square of height (m 2 ) and categorized per the Asia-Pacific classification as overweight (23.0-24.9 kg/m 2 ), obesity class I (25.0-29.9 kg/m 2 ), and obesity class II (≥30.0 kg/m 2 ). Results : CKD developed in 34.2% of 3098 men and 34.8% of 4391 women. The mean follow-up times were 7.41 years for men and 8.25 years for women. During follow-up, the BMI distributions for men were 5.0% underweight, 43.3% normal weight, 25.6% overweight, 24.1% obesity class I, and 2.0% obesity class II; those for women were 7.7%, 50.5%, 20.5%, 18.3%, and 2.9%, respectively. Compared with normal weight, obesity class I was associated with a 6% (95% confidence interval [CI]: 2-10%) shorter time to CKD onset in men and 5% (95% CI: 2-7%) in women. In both sexes, obesity class II showed shorter survival times than normal weight by point estimates, although all 95% CIs crossed the null value. Conclusions : Obesity, as classified by the Asia-Pacific BMI system, shortened the time to CKD onset in non-diabetic Asians. The conventional BMI cutoff for obesity (≥30.0 kg/m 2 ) may be too high to identify CKD risk in this population. The findings of this study may be useful for public health professionals in designing interventions to prevent CKD. more...