434 research outputs found
Effects of Imposed Bending on Microtubule Sliding in Sperm Flagella
AbstractThe movement of eukaryotic flagella is characterized by its oscillatory nature [1]. In sea urchin sperm, for example, planar bends are formed in alternating directions at the base of the flagellum and travel toward the tip as continuous waves. The bending is caused by the orchestrated activity of dynein arms to induce patterned sliding between doublet microtubules of the flagellar axoneme. Although the mechanism regulating the dynein activity is unknown, previous studies [2â7] have suggested that the flagellar bending itself is important in the feedback mechanism responsible for the oscillatory bending. If so, experimentally bending the microtubules would be expected to affect the sliding activity of dynein. Here we report on experiments with bundles of doublets obtained by inducing sliding in elastase-treated axonemes [8]. Our results show that bending not only âswitchesâ the dynein activity on and off but also affects the microtubule sliding velocity, thus supporting the idea that bending is involved in the self-regulatory mechanism underlying flagellar oscillation
Evaluation of fat-free mass by whole-body counter in Japanese healthy young adults
Whole-body counters (WBCs) are special instruments for measuring internal irradiation doses and are usually housed within or around nuclear facilities in the event of unexpected radiation emergencies. As a substantial proportion of total body potassium (TBK) is found in fat-free mass (FFM), FFM volume can be predicted from WBC-measured 40K. We screened TBK in Japanese healthy young adults using a WBC and found strong linear correlations between TBK and lean body mass (LBM) and body mass index (r = 0.97, Pâ<â0.01 and r = 0.47, Pâ<â0.01, respectively). Multiple linear regression analysis, following adjustments for sex, indicates that only LBM has a significant correlation with TBK (Pâ<â0.01). These results strongly support the feasibility of using WBCs for estimating FF
Feasibility study of a novel wireless localization technique using radiofrequency identification markers for small and deeply located lung lesions
Objectives: To evaluate the safety and efficacy of a novel wireless localization technique that uses radiofrequency identification markers for small and deep lung lesions. Methods: Preliminary use of the device was retrospectively evaluated in 2 Japanese centers. Under general anesthesia, a marker was placed as close as possible to the tumor via computed tomography-guided bronchoscopy in a hybrid operation theater. Surgeons located the marker without lung palpation using a detection probe the tone of which changed to indicate the marker-probe distance. Efficacy was defined as functional marker placement (bronchoscopy time and marker position) and deep margin distance. Results: Twelve markers were placed for 11 lesions (mean size, 6.8 ± 2.7 mm) located at a mean depth from the pleura of 11.4 ± 8.4 mm (range = 0-26.0 mm). Of 12 markers, 7 markers (58.3%) were placed within 10 mm from the lesion in 25.5 ± 14.4 minutes. For the 11 wedge resections, markers were placed at a mean distance of 6.7 mm (range, 0-13.0 mm) from the lesion and a mean distance of 14.4 mm (range, 3.0-42.0 mm) from the pleura. All markers were recovered without complications, and all tumors were resected with negative margins. For 5 lesions >10 mm deep to the pleura (mean depth, 18.9 ± 5.5 mm; range, 11.0-26.0 mm), the median depth of the surgical margin was 11.6 ± 2.1 mm (range, 9.0-14.0 mm). Conclusions: Radiofrequency identification marking was safe and precisely localized small lung lesions, including their depth
Nuclear translocation of ATBF1 is a potential prognostic maker for skin cancer
The AT motif binding factor 1 (ATBF1) is expressed in varioustissues, such as brain, liver, lung, and gastrointestinal tract, and hasan important role in cell differentiation in organs. ATBF1 interacts withPIAS3, a protein inhibitor for activated signal transducer and activatorof transcription (STAT3), to suppress STAT3 signaling, which has criticalroles in cell proliferation, migration, and survival. We hypothesized thatATBF1 is a useful prognostic marker for skin cancer. We performed immunohistochemicalanalyses of squamous cell carcinoma (SCC, n=7),basal cell carcinoma (BCC, n=4), and Bowenâs disease (n=4) tissues usingan anti-ATBF1 monoclonal antibody. All cases of BCC and Bowenâsdisease exhibited intense nuclear ATBF1 staining, whereas only someSCC cases exhibited weakly positive nuclear ATBF1 staining. SCC andBowenâs disease showed intense nuclear STAT3 staining, while BCC hadfew STAT3-positive nuclei. Based on these observations, nuclear ATBF1staining was associated with low malignancy profiles. The pattern ofATBF1 staining is a potential prognostic marker for skin cancer
Relationship between acetaldehyde concentration in mouth air and tongue coating volume
Objective Acetaldehyde is the first metabolite of ethanol and is produced in the epithelium by mucosal ALDH, while higher levels are derived from microbial oxidation of ethanol by oral microflora such as Candida species. However, it is uncertain whether acetaldehyde concentration in human breath is related to oral condition or local production of acetaldehyde by oral microflora. The aim of this pilot study was to investigate the relationship between physiological acetaldehyde concentration and oral condition in healthy volunteers. Material and Methods Sixty-five volunteers (51 males and 14 females, aged from 20 to 87 years old) participated in the present study. Acetaldehyde concentration in mouth air was measured using a portable monitor. Oral examination, detection of oral Candida species and assessment of alcohol sensitivity were performed. Results Acetaldehyde concentration [median (25%, 75%)] in mouth air was 170.7 (73.5, 306.3) ppb. Acetaldehyde concentration in participants with a tongue coating status score of 3 was significantly higher than in those with a score of 1 (
Radiation therapy induces an abscopal effect and upregulates programmed death-ligand 1 expression in a patient with non-small cell lung cancer
Radiation therapy (RT) activates the antigen presentation of dendritic cells and priming of cancer-specific cytotoxic CD8+ T cells, occasionally resulting in a systemic immune response to the tumor outside of the treatment field. The phenomenon of tumor regression at the site distant from irradiated fields is known as the abscopal effect. Several case reports have indicated a potential role of RT in overcoming primary and acquired resistance against immune checkpoint inhibitors in non-small cell lung cancer (NSCLC) and melanoma patients. We herein report an NSCLC patient who developed acquired resistance to an RT-induced abscopal effect and subsequently experienced reactivation of the systemic antitumor immune response by pembrolizumab, an antiprogrammed death 1 antibody. In this case, RT not only induced an abscopal effect but also upregulated the programmed death-ligand 1 expression outside of the irradiated field when the patient developed resistance to the abscopal effect. This case can facilitate our understanding of the mechanism underlying the RT-induced systemic immune response against cancer cells and adaptive resistance mechanism of cancer cells from immune surveillance. These findings highlight the promising results of current clinical trials combining RT and immune checkpoint inhibitors. Ongoing clinical trials will further establish evidence supporting combination therapy with RT and immune checkpoint inhibitors
Phylogenetic Analysis of E. zuernii and E. bovis with Nuclear 18S rRNA and Mitochondrial CO1 Genes
Poster Sessio
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