Single-molecule analysis of intracellular insulin granule behavior and its application to analyzing cytoskeletal dependence and pathophysiological implications

Introduction: Mobilization of intracellular insulin granules to the plasma membrane plays a crucial role in regulating insulin secretion. However, the regulatory mechanisms of this mobilization process have been poorly understood due to technical limitations. In this study, we propose a convenient approach for assessing intracellular insulin granule behavior based on single-molecule analysis of insulin granule membrane proteins labeled with Quantum dot fluorescent nanocrystals.Methods: This approach allows us to analyze intracellular insulin granule movement with subpixel accuracy at 33 fps. We tracked two insulin granule membrane proteins, phogrin and zinc transporter 8, fused to HaloTag in rat insulinoma INS-1 cells and, by evaluating the tracks with mean-square displacement, demonstrated the characteristic behavior of insulin granules.Results and discussion: Pharmacological perturbations of microtubules and F-actin affected insulin granule behavior on distinct modalities. Specifically, microtubule dynamics and F-actin positively and negatively regulate insulin granule behavior, respectively, presumably by modulating each different behavioral mode. Furthermore, we observed impaired insulin granule behavior and cytoskeletal architecture under chronic treatment of high concentrations of glucose and palmitate. Our approach provides detailed information regarding intracellular insulin granule mobilization and its pathophysiological implications. This study sheds new light on the regulatory mechanisms of intracellular insulin granule mobilization and has important implications for understanding the pathogenesis of diabetes

Local Recurrence and Complications after Percutaneous Radiofrequency Ablation of Hepatocellular Carcinoma : A Retrospective Cohort Study Focused on Tumor Location

We conducted a retrospective cohort study to investigate the predisposing factors for local recurrence and complications after percutaneous radiofrequency ablation (RFA) of hepatocellular carcinoma (HCC). HCC patients (n＝397) consecutively treated with RFA (256 males, 141 females, median age 69 years) were enrolled. In these patients, 1,455 nodules (median size 17mm) were ablated. Predisposing factors for overall recurrence and local recurrence in the context of tumor location and complications were examined. Local recurrence was observed for 113 of the 1,455 nodules. The 1-, 3- and 5-year local recurrence rates were 2.2ｵ, 7.4ｵ and 9.5ｵ, respectively. A multivariate Cox proportional hazard analysis revealed that large tumor size (＞2cm), tumor location (adjacent to the major portal branch or hepatic vein), and small ablated margin (＜3mm) were independent predisposing factors for local recurrence after RFA (HR＝1.70-2.81). Tumor location (adjacent to the major portal branch, hepatic vein, or diaphragm) was also revealed as a risk factor for liver damage due to RFA. HCC adjacent to the major portal vein or hepatic vein was associated with a higher risk for local recurrence and for complications;therefore, special precautions are necessary when applying RFA to HCC near vessels even when the tumors are located at an easy-to-puncture site

Object Transportation System Mimicking the Cilia of Paramecium aurelia Making Use of the Light-Controllable Crystal Bending Behavior of a Photochromic Diarylethene

The design of an object transportation system exploiting the bending behavior of surface-assembled diarylethene crystals is reported. A photoactuated smart surface based on this system can transport polystyrene beads to a desired area depending on the direction of the incident light. Two main challenges were addressed to accomplish directional motion along a surface: first, the preparation of crystals whose bending behavior depends on the direction of incident light; second, the preparation of a film on which these photochromic crystal plates are aligned. Nuclei generation and nuclear growth engineering were achieved by using a roughness-controlled dotted microstructured substrate. This system demonstrates how to achieve a mechanical function as shown by remote-controlled motion along a surface

Transcatheter Arterial Chemoembolization to Reduce Size of Hepatocellular Carcinoma before Radiofrequency Ablation

Transcatheter arterial chemoembolization (TACE) is often performed before radiofrequency ablation (RFA) for the treatment of early-stage hepatocellular carcinoma (HCC). TACE prior to RFA can expand the ablated area and reduce the tumor size, facilitating complete ablation. However, the factors correlated with size reduction remain uncertain. The aim of this study was to identify the factors associated with size reduction by TACE and develop a formula to predict the reduction rate. A total of 100 HCC patients treated with TACE followed by RFA at least 20 days later were enrolled. The tumor size was measured at the time of TACE and RFA, and correlations between the reduction rate and 13 clinical factors were examined. A formula to predict the reduction rate was built using the factors obtained by the analysis. Reduction in the tumor size was observed in 69 nodules, and the median reduction rate was 16.2%. A multivariate regression analysis revealed that a large tumor size (p< 0.01) and a long interval between the therapies (p= 0.01) were factors for a high tumor reduction rate, with tumor size more strongly related to the degree of reduction. A size reduction of more than 10% can be expected by waiting 20 days after TACE when the size of the tumor at TACE is over 25 mm in diameter. The tumor siz

Photoinduced swing of a diarylethene thin broad sword shaped crystal:a study on the detailed mechanism

We report a swinging motion of photochromic thin broad sword shaped crystals upon continuous irradiation with UV light. By contrast in thick crystals, photosalient phenomena were observed. The bending and swinging mechanisms are in fact due to molecular size changes as well as phase transitions. The first slight bending away from the light source is due to photocyclization-induced surface expansion, and the second dramatic bending toward UV incidence is due to single-crystal-to-single-crystal (SCSC) phase transition from the original phase I to phase IIUV. Upon visible light irradiation, the crystal returned to phase I. A similar SCSC phase transition with a similar volume decrease occurred by lowering the temperature (phase IIItemp). For both photoinduced and thermal SCSC phase transitions, the symmetry of the unit cell is lowered; in phase IIUV the twisting angle of disordered phenyl groups is different between two adjacent molecules, while in phase IIItemp, the population of the phenyl rotamer is different between adjacent molecules. In the case of phase IIUV, we found thickness dependent photosalient phenomena. The thin broad sword shaped crystals with a 3 mu m thickness showed no photosalient phenomena, whereas photoinduced SCSC phase transition occurred. In contrast, large crystals of several tens of mu m thickness showed photosalient phenomena on the irradiated surface where SCSC phase transition occurred. The results indicated that the accumulated strain, between isomerized and non-isomerized layers, gave rise to the photosalient phenomenon

Phenotypic Plasticity of Mouse Spermatogonial Stem Cells

BACKGROUND:Spermatogonial stem cells (SSCs) continuously undergo self-renewal division to support spermatogenesis. SSCs are thought to have a fixed phenotype, and development of a germ cell transplantation technique facilitated their characterization and prospective isolation in a deterministic manner; however, our in vitro SSC culture experiments indicated heterogeneity of cultured cells and suggested that they might not follow deterministic fate commitment in vitro. METHODOLOGY AND PRINCIPAL FINDINGS:In this study, we report phenotypic plasticity of SSCs. Although c-kit tyrosine kinase receptor (Kit) is not expressed in SSCs in vivo, it was upregulated when SSCs were cultured on laminin in vitro. Both Kit(-) and Kit(+) cells in culture showed comparable levels of SSC activity after germ cell transplantation. Unlike differentiating spermatogonia that depend on Kit for survival and proliferation, Kit expressed on SSCs did not play any role in SSC self-renewal. Moreover, Kit expression on SSCs changed dynamically once proliferation began after germ cell transplantation in vivo. CONCLUSIONS/SIGNIFICANCE:These results indicate that SSCs can change their phenotype according to their microenvironment and stochastically express Kit. Our results also suggest that activated and non-activated SSCs show distinct phenotypes

Comparison of percutaneous radiofrequency thermal ablation and surgical resection for small hepatocellular carcinoma

<p>Abstract</p> <p>Background</p> <p>The purpose of this investigation was to compare the outcome of percutaneous radiofrequency thermal ablation therapy (PRFA) with surgical resection (SR) in the treatment of single and small hepatocellular carcinoma (HCC).</p> <p>Methods</p> <p>We conducted a retrospective cohort study on 231 treatment naive patients with a single HCC ≤ 3 cm who had received either curative PRFA (162 patients) or curative SR (69 patients). All patients were regularly followed up after treatment at our department with blood and radiologic tests.</p> <p>Results</p> <p>The 1-, 3- and 5-year overall survival rates after PRFA and SR were 95.4%, 79.6% and 63.1%, respectively in the PRFA group and 100%, 81.4% and 74.6%, respectively in the SR group. The corresponding recurrence free survival rates at 1, 3 and 5 years after PRFA and SR were 82.0%, 38.3% and 18.0%, respectively in the PRFA group and 86.0%, 47.2% and 26.0%, respectively in the SR group. In terms of overall survival and recurrence free survival, there were no significant differences between these two groups. In comparison of PRFA group patients with liver cirrhosis (LC) (n = 127) and SR group patients with LC (n = 50) and in comparison of PRFA group patients without LC (n = 35) and SR group patients without LC (n = 19), there were also no significant differences between two groups in terms of overall survival and recurrence free survival. In the multivariate analysis of the risk factors contributing to overall survival, serum albumin level was the sole significant factor. In the multivariate analysis of the risk factors contributing to recurrence free survival, presence of LC was the sole significant factor. The rate of serious adverse events in the SR group was significantly higher than that in the PRFA group (P = 0.023). Hospitalization length in the SR group was significantly longer than in the PRFA group (P = 0.013).</p> <p>Conclusions</p> <p>PRFA is as effective as SR in the treatment of single and small HCC, and is less invasive than SR. Therefore, PRFA could be a first choice for the treatment of single and small HCC.</p

Post-vasectomy semen analysis: Optimizing laboratory procedures and test interpretation through a clinical audit and global survey of practices

Purpose: The success of vasectomy is determined by the outcome of a post-vasectomy semen analysis (PVSA). This article describes a step-by-step procedure to perform PVSA accurately, report data from patients who underwent post vasectomy semen analysis between 2015 and 2021 experience, along with results from an international online survey on clinical practice. Materials and Methods: We present a detailed step-by-step protocol for performing and interpretating PVSA testing, along with recommendations for proficiency testing, competency assessment for performing PVSA, and clinical and laboratory scenarios. Moreover, we conducted an analysis of 1,114 PVSA performed at the Cleveland Clinic’s Andrology Laboratory and an online survey to understand clinician responses to the PVSA results in various countries. Results: Results from our clinical experience showed that 92.1% of patients passed PVSA, with 7.9% being further tested. A total of 78 experts from 19 countries participated in the survey, and the majority reported to use time from vasectomy rather than the number of ejaculations as criterion to request PVSA. A high percentage of responders reported permitting unprotected intercourse only if PVSA samples show azoospermia while, in the presence of few non-motile sperm, the majority of responders suggested using alternative contraception, followed by another PVSA. In the presence of motile sperm, the majority of participants asked for further PVSA testing. Repeat vasectomy was mainly recommended if motile sperm were observed after multiple PVSA’s. A large percentage reported to recommend a second PVSA due to the possibility of legal actions. Conclusions: Our results highlighted varying clinical practices around the globe, with controversy over the significance of non-motile sperm in the PVSA sample. Our data suggest that less stringent AUA guidelines would help improve test compliance. A large longitudinal multi-center study would clarify various doubts related to timing and interpretation of PVSA and would also help us to understand, and perhaps predict, recanalization and the potential for future failure of a vasectomy.American Center for Reproductive Medicin

Expression of ALDH1 in axillary lymph node metastases is a prognostic factor of poor clinical outcome in breast cancer patients with 1–3 lymph node metastases

Background Recently, evidence in support of the cancer stem cell (CSC) hypothesis has been accumulating. On the other hand, it has been reported that the expression of aldehyde dehydrogenase 1 (ALDH1) in primary breast cancer is a powerful predictor of a poor clinical outcome, and that breast cancer stem cells express ALDH1. According to the CSC hypothesis, development of metastases requires the dissemination of CSC that may remain dormant and be reactivated to cause tumor recurrence. In this study, we investigated whether the detection of CSC in axillary lymph node metastases (ALNM) might be a significant prognostic factor in patients with breast cancer. Methods From 1998 to 2006, 40 primary breast cancer patients with ALNM, the number of metastatic nodes varying in number from 1 to 3, underwent surgery at Okayama University; of these, 15 patients developed tumor recurrence. We retrospectively evaluated the common clinicopathological features and the expression of ER, HER2, ALDH1, and Ki67 in both the primary lesions and the ALNM, and analyzed the correlations between the expression of these biological markers and the disease-free survival (DFS). Results Expression of ALDH1 in the ALNM was significantly associated with the DFS (P = 0.037). Conclusion Evaluation of biomarker expression in ALNM could be useful for prognosis in breast cancer patients with 1–3 metastatic lymph nodes