In situ fabrication of silver/polyimide composite films with enhanced heat dissipation

In this study, silver/polyimide (Ag/PI) composite films with enhanced heat dissipation properties were prepared. Ag was formed in situ by reducing AgNO₃ at various locations according to the reduction method. Two different types of soluble PIs capable of solution processing were used, namely Matrimid and hydroxy polyimide (HPI). Unlike Matrimid with bulky substituents, HPI with polar hydroxy groups formed ion–dipole interactions with Ag ions to form Ag particles with uniform size distribution. The location and distribution of Ag particles affect the heat emission characteristics of the composite films, resulting in better heat dissipation properties with the thermally and photochemically reduced Ag/HPI films having more Ag particles distributed inside of the films than the chemically reduced films.

The chemical structure and reduction method influence the Ag dispersion in Ag/PI nanocomposite films, resulting in different heat dissipation properties.     

Pathologic Validation of Endoscopic Ablative Therapy for Gastric Epithelial Neoplasia: A Randomized Controlled Trial

BackgroundThe effectiveness of endoscopic ablative therapy such as monopolar coagulation (MC) or argon plasma coagulation (APC) have not been validated histologically. The aim of this study was the histologic validation of endoscopic ablative therapy for gastric epithelial neoplasia.Methods: We designed a prospective randomized controlled trial involving patients with gastric low-grade dysplasia. Patients were randomly assigned to either the APC or the MC group. Endoscopic ablative therapy was followed by endoscopic submucosal dissection (ESD) for histologic evaluation. The main outcome was histologic completeness of endoscopic ablative therapy. Results: Sixty-eight patients were recruited, of whom 34 patients underwent APC and 34 patients underwent MC followed by ESD. The APC group showed significantly higher complete eradication rate compared to the MC group (55.9% vs. 11.8%, P < .001). APC was the only significant predictor of histologic complete eradication in multivariate analysis (OR: 7.66; 95% CI: 2.139-27.448). No adverse events related to the procedure occurred in either group.Conclusions: Although APC is a more effective treatment option than MC in the management of gastric epithelial neoplasia, the effectiveness of both methods was limited in eradicating gastric epithelial neoplasia completely. Therefore, endoscopic resection should be a first option for treatment of gastric epithelial neoplasia until the optimal method is established with further studies.     

Association of Household Income Level with Vitamin and Mineral Intake

Appropriate nutrient intake is essential for maintaining health and resisting disease. The current study investigated the association between household income quintile and nutrient intake using data from KNHANES 2019. A total of 5088 South Korean adults were analyzed. The estimated average requirement cut-point method, extended to handle participants with intakes higher than the tolerable upper level, was utilized to determine the need for dietary modification. The suitability of overall vitamin, overall mineral, and individual nutrient intake was evaluated by logistic regression analysis. Subgroup analysis was performed on overall mineral intake suitability. None of the individual nutrients had an intake ratio of over 70%, with the ratio being under 30% for some nutrients. The intake of iron, phosphorus, vitamin B9, and vitamin C had a significant upward trend as household income rose. A subgroup analysis revealed sex differences in the trends of overall mineral intake. The results revealed that some nutrients are not consumed appropriately in the Korean population. Furthermore, they suggest that household income is significantly associated with the intake of overall minerals and several individual nutrients. These results suggest that nutritional assistance is required for certain vulnerable groups, and provide supplementary data for appropriate interventions or further research.     

Role of the inflamed synovial volume of the wrist in defining remission of rheumatoid arthritis with gadolinium-enhanced 3D-SPGR MR imaging.

The purpose of this study was to assess the role of inflamed synovial volume (ISV) in defining a state of remission in rheumatoid arthritis (RA) with contrast-enhanced, fat-suppression, three-dimensional (3D) gradient-recalled acquisition in the steady state with radiofrequency spoiling (SPGR) magnetic resonance (MR) imaging. Sixteen patients with RA (5 remission and 11 non-remission patients) were enrolled in this study. Contrast-enhanced, fat-suppression, 3D-SPGR MR imaging was performed before (n = 12) and after (n = 16) a mean 17 months of disease-modifying antirheumatic drugs (DMARDs). ISV was calculated by using a segmentation method. Statistical analysis of changes in ISVs and residual ISVs between the remission and the non-remission groups was performed. Intra- and inter-observer reproducibility was tested. Residual ISVs and relative changes in ISVs were 3.23 +/- 1.84 cm(3) and 51.4% (range 47.6-55.2%) in the remission group and 6.26 +/- 2. 03 cm(3)and 31.4% (range -73.5-53.5%) in the non-remission group. Both values were significantly different between the two groups (P < 0.05 and 0.05, respectively). Volume measurement showed high reproducibility: Intra- and inter-observer mean percentage errors were 5.04, 7.06, and 5.09%, respectively. Residual ISVs and relative changes in ISVs measured by MR imaging may provide objective and quantitative parameters in defining a state of remission in RA after therapy; however, the clinical utility of these measurements remains to be verified. J. Magn. Reson. Imaging 1999;10:202-208.     

An integrated service digital network (ISDN)-based international telecommunication between Samsung Medical Center and Hokkaido University using telecommunication helped radiotherapy planning and information system (THERAPIS).

This study introduces the integrated service digital network (ISDN)-based international teleradiotherapy system (THERAPIS) in radiation oncology between hospitals in Seoul, South Korea and in Sapporo, Japan. THERAPIS has the following functions: (1) exchange of patient's image data, (2) real-time teleconference, and (3) communication of the treatment planning, dose calculation and distribution, and of portal verification images between the remote hospitals. Our preliminary results of applications on eight patients demonstrated that the international telecommunication using THERAPIS was clinically useful and satisfactory with sufficient bandwidth for the transfer of patient data for clinical use in radiation oncology.     

Erdheim-Chester disease: a case report.

A 42-year-old man with Erdheim-Chester disease (EC) is presented. This is the first case of this disease reported in Korea. The patient complained of knee pain and plain roentgenogram of the bilateral legs revealed diffusely increased density, coarsened trabecular pattern, and cortical thickening in the diaphysis, and metaphysis as well as epiphysis. Magnetic resonance imaging revealed that the lesions showed low signal intensity on T1-weighted images and heterogeneously low and high signal intensity on T2-weighted images. Histological examination of the biopsy specimen showed a xanthogranulomatous lesion consisting aggregations of foamy histiocytes and Touton-type giant cells. Immunohistochemical staining showed positive reaction to anti-S-100 and lysozyme in the cytoplasm of the giant cells.     

Decreased metastatic spread in mice homozygous for a null allele of the cystatin C protease inhibitor gene.

AIMS: Increased or altered activities of cysteine proteases have been implicated in serious human disorders such as cancer, rheumatoid arthritis, sepsis, and osteoporosis. To improve the current knowledge of the regulatory role of a major mammalian cysteine protease inhibitor, cystatin C, in such disease processes, a cystatin C deficient mouse was generated and characterized. METHODS: The mouse cystatin C gene was inactivated by insertion of a bacterial neo gene through homologous recombination in 129/Sv embryonic stem cells. Embryonic stem cell clones were injected into C57BL/6J blastocysts followed by injection of the blastocysts into pseudopregnant female mice. F1 offspring with agouti coat colour after mating of chimaeric males with C57BL/6J females were examined by DNA analysis, and mice carrying the targeted mutation were intercrossed to obtain homozygous cystatin C deficient (CysC-/-) mice. To study the role of cysteine proteases and their inhibitors in metastasis, the spread of B16-F10 melanoma cells in CysC-/- and wild-type mice was compared. Analysis of the formation of remote metastases was carried out by intravenous injection of beta-galactosidase transfected B16-F10 cells and subsequent determination of cancer cell colonies in the lungs. RESULTS: Cystatin C deficient mice were fertile and showed no gross pathological abnormality up to 6 months of age. Compared with wild-type mice, seven times fewer large metastatic colonies were counted by means of a dissecting microscope in CysC-/- mice two weeks after tail vein injection of B16-F10 cells. At all of eight time points from 15 minutes to two weeks after intravenous injection of tumour cells, the CysC-/- mice had significantly fewer lung metastases. The observed differences were smaller when beta-galactosidase transfected cells were used to allow counting of small colonies. Subcutaneous and intracerebral tumour growth was not different in the CysC-/- mice. CONCLUSIONS: Cystatin C concentrations in vivo might influence metastasis in some tissues. The decreased metastatic spread of B16-F10 cells in CysC-/- mice is the result of both reduced seeding and reduced growth of tumour cells in their lungs.     

Bilateral nephrectomy, peritoneal dialysis and subsequent cadaveric renal transplantation for treatment of renal failure due to polycystic kidney disease requiring continuous ventilation

We report here on a newborn with end-stage renal failure due to autosomal recessive polycystic kidney disease, also causing ventilation-requiring respiratory distress. Peritoneal dialysis was able to keep the newborn alive but not wean it from the respirator. After removal of both huge kidneys, dialysis became more effective and allowed the neonate to be extubated only 5 days later. It was decided to register the baby for a pediatric cadaveric kidney transplant when it reached 6 kg/body wt or to perform a living related transplant if no such kidney became available and the baby grew to 7 kg/body wt. At the age of 9 months and a weight of 6 kg a cadaveric kidney from a 20-month-old donor became available and was transplanted extraperitoneally. Prophylactic immunosuppression included cyclosporin, mycophenolate mofetil and steroids. Pneumonia on post-operative day 10 required respiratory care for several days and acute rejection requiring peritoneal dialysis. Both complications were controlled with antibiotics and conversion from cyclosporin to tacrolimus and a temporary increase in steroids. Thirteen months later the child is alive and well with a serum creatinine of 0.6 mg%. From this experience we would recommend early removal of both polycystic kidneys causing end-stage renal failure and respiratory insufficiency, starting peritoneal dialysis and performing a renal transplant as soon as possible. This therapeutic strategy seems appropriate for this complex situation.     

Comparison of retentive force and wear pattern of Locator® and ADD-TOC attachments combined with CAD-CAM milled bar

PURPOSEThe purpose of this study was to investigate changes in retention and wear pattern of Locator® and ADD-TOC attachments on a digital milled bar by performing chewing simulation and repeated insertion/removal of prostheses in fully edentulous models.MATERIALS AND METHODSLocator (Locator®; Zest Anchors Inc., Escondido, CA, USA) was selected as the control group and ADD-TOC (ADD-TOC; PNUAdd Co., Ltd., Busan, Republic of Korea) as the experimental group. A CAD-CAM milled bar was mounted on a master model and 3 threaded holes for connecting a bar attachment was formed using a tap. Locator and ADD-TOC attachments were then attached to the milled bar. Simulated mastication and repeated insertion/removal were performed over 400,000 cyclic loadings and 1,080 insertions/removals, respectively. Wear patterns on deformed attachment were investigated by field emission scanning electron microscopy.RESULTSFor the ADD-TOC attachments, chewing simulation and repeated insertion/removal resulted in a mean initial retentive force of 24.43 ± 4.89 N, which were significantly lower than that of the Locator attachment, 34.33 ± 8.25 N (P < .05). Amounts of retention loss relative to baseline for the Locator and ADD-TOC attachments were 21.74 ± 7.07 and 8.98 ± 5.76 N (P < .05).CONCLUSIONCAD-CAM milled bar with the ADD-TOC attachment had a lower initial retentive force than the Locator attachment. However, the ADD-TOC attachment might be suitable for long-term use as it showed less deformation and had a higher retentive force after simulated mastication and insertion/removal repetitions.