Photoimageable Organic Coating Bearing Cyclic Dithiocarbonate for a Multifunctional Surface.

We report the fabrication of photocross-linkable and surface-functionalizable polymeric thin films using reactive cyclic dithiocarbonate (DTC)-containing copolymers. The chemical functionalities of these material surfaces were precisely defined with light illumination. The DTC copolymers, namely, poly(dithiocarbonate methylene methacrylate-random-alkyl methacrylate)s, were synthesized via reversible addition-fragmentation chain transfer polymerization, and the reaction kinetics was thoroughly analyzed. The copolymers were cross-linked into a coating using a bifunctional urethane cross-linker that contains a photolabile o-nitrobenzyl group and releases aniline upon exposure to light. The nucleophilic attack of the aromatic amine opens the DTC group, forming a carbamothioate bond and generating a reactive thiol group in the process. The surface concentrations of the unreacted DTC and thiol were effectively controlled by varying the amounts of the copolymer and the cross-linker. The use of methacrylate comonomers led to additional reactive surface functionality such as carboxylic acid via acid hydrolysis. The successful transformations of the resulting DTC, thiol, and carboxylic acid groups to different functionalities via sequential nucleophilic ring opening, thiol-ene, and carbodiimide coupling reactions under ambient conditions were confirmed quantitatively using X-ray photoelectron spectroscopy. The presented chemistries were readily adapted to the immobilization of complex molecules such as a fluorophore and a protein in lithographically defined regions, highlighting their potential in creating organic coatings that can have multiple functional groups under ambient conditions.

X-ray-Based Spectroscopic Techniques for Characterization of Polymer Nanocomposite Materials at a Molecular Level.

This review provides detailed fundamental principles of X-ray-based characterization methods, i.e., X-ray photoelectron spectroscopy, energy-dispersive X-ray spectroscopy, and near-edge X-ray absorption fine structure, and the development of different techniques based on the principles to gain deeper understandings of chemical structures in polymeric materials. Qualitative and quantitative analyses enable obtaining chemical compositions including the relative and absolute concentrations of specific elements and chemical bonds near the surface of or deep inside the material of interest. More importantly, these techniques help us to access the interface of a polymer and a solid material at a molecular level in a polymer nanocomposite. The collective interpretation of all this information leads us to a better understanding of why specific material properties can be modulated in composite geometry. Finally, we will highlight the impacts of the use of these spectroscopic methods in recent advances in polymer nanocomposite materials for various nano- and bio-applications.

Bariatric/Metabolic Surgery Induces Noticeable Changes of Microbiota and Their Secreting Extracellular Vesicle Composition in the Gut.

INTRODUCTION: Microbial ecology is reported to be an important regulator of energy homeostasis and glucose metabolism. Microbes secrete extracellular vesicles (EVs) during their proliferation and death to communicate with other cells. To investigate the roles of gut microbiota in glucose metabolism, we analyzed serial changes of gut microbe and microbial EV composition before and after bariatric/metabolic surgery (BMS). METHODS: Twenty-eight Wistar rats were fed on high-fat diet (HFD) to induce obesity and diabetes. Five of them compared with 5 rats fed on regular chow diet (RCD). Among the remaining 23 rats, Roux-en-Y gastric bypass (RYGB) (n = 10), sleeve gastrectomy (SG) (n = 10), or sham operation (n = 3) was randomly performed. Gut microbiota and EVs from fecal samples were analyzed by 16S rDNA amplicon sequencing. RESULTS: The present study showed that microbial diversity was decreased in HFD-fed rats versus RCD-fed rats. In addition, BMS reversed glucose intolerance and microbial richness which were induced by HFD. In terms of microbiota and microbial EV composition, both RYGB and SG enhance the composition of phyla Proteobacteria, Verrucomicrobia, and their secreting EVs, but decrease phylum Firmicutes and its EVs. We tried to demonstrate specific genera showed a significant compositional difference in obesity/diabetes-induced rats compared with normal rats and then restored similarly toward normal rats' level after BMS. At the genus level, Lactococcus, Ruminococcus, Dorea in Firmicutes(p), Psychrobacter in Proteobacteria(p), and Akkermansia in Verrucomicrobia(p) fit these conditions after BMS. CONCLUSION: We suggest that these genera are the candidates contributing to obesity and diabetes improvement mechanism after BMS.

Retention of the mother and child health handbook and additional immunization of Japanese encephalitis and tetanus vaccine.

BACKGROUND: Improvement of additional immunization rate is indicated as an important factor for effective immunization of diseases. In this study, the relationship between retention of mother and child health handbook and additional immunization rate of Japanese encephalitis and tetanus was examined. METHODS: A survey via questionnaire was performed against parents of students of middle schools in Gwangmyeong-si, Gyeonggi-do, and elementary schools in Seoul. Among 350 copies of the questionnaire delivered via post mail, 261 copies were collected and used in the analysis. The questionnaire included general features of subjects and their children, retention of the mother and child health handbook, and recognition of additional immunization of the Japanese encephalitis and tetanus vaccine. RESULTS: It was found that 80.8% of subjects answered affirmative to retaining the mother and child health handbook, and the group retaining the handbook had higher recognition rate of the need for additional immunization than the group that did not, for the Japanese encephalitis vaccine (83.2% vs. 51.2%, P < 0.001) and for the tetanus vaccine (66.5% vs. 31.7%, P < 0.001). Although the group retaining the handbook had a significantly higher additional immunization rate of the tetanus vaccine of 48.6% vs. 17.1% (P = 0.001), the immunization rate of the Japanese encephalitis vaccine did not show a significant difference (P = 0.231). The group recognizing the need for additional immunization of the Japanese encephalitis and tetanus vaccine had a significantly higher additional immunization rate than the counterpart (P < 0.001). CONCLUSION: It was considered that retention of the mother and child health handbook was related to recognition and execution of additional immunizations.

Diffuse interstitial infiltrative lung metastasis of malignant melanoma: a case report.

A diffuse interstitial infiltrative pattern of lung metastasis in a patient with malignant melanoma is rare and can be confused with benign conditions such as pulmonary edema or drug-induced pneumonitis. We experienced a case of diffuse interstitial infiltrative lung metastasis in malignant melanoma in a 37-year-old man. This case was confirmed by a transbronchial lung biopsy. We herein describe the findings on CT and positron emission tomography scan.

Clinical evaluation of compression ratios using JPEG2000 on computed radiography chest images.

The efficient compression of radiographic images is of importance for improved storage and network utilization in support of picture archiving and communication systems (PACS) applications. The DICOM Working Group 4 adopted JPEG2000 as an additional compression standard in Supplement 61 over the existing JPEG. The wavelet-based JPEG2000 can achieve higher compression ratios with less distortion than the Discrete Cosine Transform (DCT)-based JPEG algorithm. However, the degradation of JPEG2000-compressed computed radiography (CR) chest images has not been tested comprehensively clinically. The authors evaluated the diagnostic quality of JPEG2000-compressed CR chest images with compression ratios from 5:1 to 200:1. An ROC (receiver operating characteristic analysis) and t test were performed to ascertain clinical performance using the JPEG2000-compressed images. The authors found that compression ratios as high as 20:1 can be utilized without affecting lesion detectability. Significant differences between the original and the compressed CR images were not recognized up to compression ratio of 50:1 within a confidence level of 99%.