Online Automated Micro Sample Preparation for High-Performance Liquid Chromatography

Sample preparation is one of the most labor-intensive and time-consuming operations in sample analysis. Sample preparation strategies include the exhaustive or non-exhaustive extraction of analytes from matrices. Online coupling of sample preparation with the separation system is regarded as an important goal. In-tube solid-phase microextraction (SPME) is an effective sample preparation technique that uses an open tubular fused-silica capillary column as an extraction device. In-tube SPME is useful for trace enrichment, automated sample cleanup, and rapid online analysis. Moreover, this method can be used to determine the analytes in complex matrices by direct sample injection or merely by simple sample treatment such as filtration. In-tube SPME is frequently combined with high-performance liquid chromatography (HPLC) using online column-switching techniques. Various operating systems and new sorbent materials have been reported to improve extraction efficiency, such as sorption capacity and selectivity. This chapter discusses efficient micro sample preparation techniques for HPLC, especially online automated in-tube SPME

Impact of polyplex micelles installed with cyclic RGD peptide as ligand on gene delivery to vascular lesions

Gene therapy is expected to open a new strategy for the treatment of refractory vascular diseases, so the development of appropriate gene vectors for vascular lesions is needed. To realize this requirement with a non-viral approach, cyclo(RGDfK) peptide (cRGD) was introduced to block copolymer, poly(ethylene glycol)-block-polycation carrying ethylenediamine units (PEG-PAsp(DET)). cRGD recognizes αvβ3 and αvβ5 integrins, which are abundantly expressed in vascular lesions. cRGD-conjugated PEG-PAsp(DET) (cRGD-PEG-PAsp(DET)) formed polyplex micelles through complexation with plasmid DNA (pDNA), and the cRGD-PEG-PAsp(DET) micelles achieved significantly more efficient gene expression and cellular uptake as compared with PEG-PAsp(DET) micelles in endothelial cells and vascular smooth muscle cells. Intracellular tracking of pDNA showed that cRGD-PEG-PAsp(DET) micelles were internalized via caveolae-mediated endocytosis, which is associated with a pathway avoiding lysosomal degradation, and that PEG-PAsp(DET) micelles were transported to acidic endosomes and lysosomes via clathrin-mediated endocytosis. Further, in vivo evaluation in rat carotid artery with a neointimal lesion revealed that cRGD-PEG-PAsp(DET) micelles realized sustained gene expression, while PEG-PAsp(DET) micelles facilitated rapid but transient gene expression. These findings suggest that introduction of cRGD to polyplex micelles might create novel and useful functions for gene transfer and contribute to the establishment of efficient gene therapy for vascular diseases

Surgery Outcomes for Pulmonary Metastases from Renal Cell Carcinoma

Pulmonary metastatic resection is a standard therapy for renal cell carcinoma (RCC). Although patients with pulmonary metastases who do not undergo any treatment have poor prognoses, it has been reported that resection for pulmonary metastases yields good clinical outcomes. We investigated the prognoses of the 10 Japanese patients (eight males, two females) who underwent a surgical resection of pulmonary metastasectomy from RCC at our institution between April 1, 2012 and March 31, 2020 and analyzed the prognostic factors. We determined the prognoses and calculated the 5-year overall survival (OS) and disease-free survival (DFS) rates. To identify prognostic factors, we compared the median DFS duration for each factor. Elderly patients (median age, 75.5 years) were more predominant compared to previous studies, and all 10 patients underwent a complete resection. The 5-year DFS rate was 30.5% (95%CI: 0.045-0.63) and the 5-year OS rate was 80% (95%CI: 0.20-0.97). The following factors were associated with better prognosis: female, disease-free interval≥36 months, and metastases size<12 mm. These results indicate that complete resection for pulmonary metastases from RCC resulted in good clinical outcomes, particularly for patients with better prognostic factors

Roles of bulk γ(L)-Bi₂MoO₆ and surface β-Bi₂Mo₂O₉ in the selective catalytic oxidation of C₃H₆

γ(L)-Bi₂MoO₆ (L: low temperature phase) catalysts, whose surface compositions have a Mo/Bi ratio above = 0.5, exhibited high selectivity in the partial oxidation of C₃H₆, while catalysts with Mo/Bi surface ratios near or below = 0.5 exhibited low selectivity. γ(L)-phase catalysts which have Mo/Bi surface ratios greater than = 0.5, were demonstrated to form β-Bi₂Mo₂O₉ on their surface. An interaction between the β- and γ(L)-phases was observed in these catalysts’ UV–vis spectra at 430 nm. The new β-phase material seems to grow along b-axis of γ(L)-phase, i.e., perpendicular to MoO₂–Bi₂O₂ layers. Structure visualizations revealed that the α-Bi₂Mo₃O₁₂, β-, and γ(H)-phases, which are selective catalysts, contain twin Mo tetrahedral structures, and that their Mo and Bi ions lie on the same plane. The pure γ(L)-phase does not contain this structure. A model for the very rapid transfer of oxygen between the γ(L)- and β-phases is discussed in relation to the kinetics of C₃H₆ oxidation.ArticleJournal of molecular catalysis. A, Chemical. 318(1-2):94-100 (2010)journal articl

Early outcomes of thoracic endovascular aortic repair in treating type B aortic dissection

We evaluated the treatment results and aortic remodeling of Stanford type B aortic dissection （TBAD） following thoracic endovascular aortic repair （TEVAR） to determine the optimal timing to operate. Based on the duration from the onset of TBAD to surgery, 17 patients who underwent TEVAR for TBAD were divided into early （n＝10, TEVAR＜3 months from onset） and late （n＝7, TEVAR≥3 months from onset） groups. True- and false-lumen areas were measured at four levels （A-D） using contrast-enhanced computed tomography before and after TEVAR: A, immediately after the left subclavian artery branching; B, descending aorta at the tracheal bifurcation; C, aortic annulus; and D, diaphragm. The durations from the onset of TBAD to TEVAR were 46±25 days and 7.0±5.3 years in the early and late groups, respectively. No major intraoperative complications were observed in either group. However, the early group had one case of retrograde type A aortic dissection 54 days after TEVAR. In the early group, true-lumen area increased at all levels, except at level A, whereas false-lumen areas decreased at all levels （p＜0.05）. The late group showed no tendencies, except for an increased true-lumen area at level B. A difference in early aortic remodeling was observed—true-lumen area enlargement and false-lumen area decrease were more marked in the early group than the late group. TEVAR is useful when performed early after TBAD onset （within 3 months） and results in good aortic remodeling. In the late phase, the effect might be relatively smaller

A case of Langerhans cell sarcoma on the scalp: Whole‐exome sequencing reveals a role of ultraviolet in the pathogenesis

Langerhans cell sarcoma (LCS) is a high‐grade neoplasm with overtly malignant cytological features and a Langerhans cell phenotype. The underlying genetic features are poorly understood, and only a few alterations, such as those of the MARK pathway‐related genes, CDKN2A and TP53 have been reported. Here we present a 70‐year‐old male with LCS on the scalp and pulmonary metastasis. The multinodular tumor, 3.0 cm in diameter, consisted of diffusely proliferated pleomorphic cells with numerous mitoses (53/10 HPFs). Immunohistochemically, the tumor cells were positive for CD1a, Langerin and PD‐L1, and the Ki‐67 labeling index was 50%. These pathological features were consistent with LCS, and were also observed in the metastatic tumor. Whole‐exome sequencing revealed that both the primary and metastatic tumors harbored a large number of mutations (>20 mutations/megabase), with deletion of CDKN2A and TP53 mutation, and highlighted that the mutational signature was predominantly characteristic of ultraviolet (UV) exposure (W = 0.828). Our results suggest, for the first time, that DNA damage by UV could accumulate in Langerhans cells and play a role in the pathogenesis of LCS. The high mutational burden and PD‐L1 expression in the tumor would provide a rationale for the use of immune checkpoint inhibitors for treatment of unresectable LCS

Antimicrobial Property of Titanium Plates Treated with Silica-Bound Protamine

Antimicrobial activity is necessary for dental prosthetic devices to maintain oral and systemic health in elderly people wearing prostheses. In particular, dental prosthetic devices with antifungal properties are urgently needed to prevent aspiration pneumonia. However, practical application methods to deliver antimicrobial properties to dental prosthetic devices have not yet been established. Therefore, in this study we aimed to fix protamine on titanium plates treated with silica coating using a Silano-Pen, and to evaluate the antimicrobial properties of the titanium plates against Candida albicans. Strong antifungal properties were obtained by soaking titanium plates in an aqueous protamine solution after silica coating treatment. Since this brand-new method is simple, its practical application is expected in the near future