• 제목/요약/키워드: Releasing methods

검색결과 239건 처리시간 0.028초

Influence of shape and finishing on the corrosion of palladium-based dental alloys

  • Milheiro, Ana;Muris, Joris;Kleverlaan, Cornelis J.;Feilzer, Albert J.
    • The Journal of Advanced Prosthodontics
    • /
    • 제7권1호
    • /
    • pp.56-61
    • /
    • 2015
  • PURPOSE. The purpose of this study was to evaluate the effects of the surface treatment and shape of the dental alloy on the composition of the prosthetic work and its metallic ion release in a corrosive medium after casting. MATERIALS AND METHODS. Orion Argos (Pd-Ag) and Orion Vesta (Pd-Cu) were used to cast two crowns and two disks. One of each was polished while the other was not. Two as-received alloys were also studied making a total of 5 specimens per alloy type. The specimens were submersed for 7 days in a lactic acid/sodium chloride solution (ISO standard 10271) and evaluated for surface structure characterization using SEM/EDAX. The solutions were quantitatively analysed for the presence of metal ions using ICP-MS and the results were statistically analysed with one-way ANOVA and a Tukey post-hoc test. RESULTS. Palladium is released from all specimens studied (range $0.06-7.08{\mu}g{\cdot}cm^{-2}{\cdot}week^{-1}$), with the Pd-Cu alloy releasing the highest amounts. For both types of alloys, ion release of both disk and crown pairs were statistically different from the as-received alloy except for the Pd-Ag polished crown (P>.05). For both alloy type, disk-shaped pairs and unpolished specimens released the highest amounts of Pd ions (range $0.34-7.08{\mu}g{\cdot}cm^{-2}{\cdot}week^{-1}$). Interestingly, in solutions submerged with cast alloys trace amounts of unexpected elements were measured. CONCLUSION. Shape and surface treatment influence ion release from dental alloys; polishing is a determinant factor. The release rate of cast and polished Pd alloys is between $0.06-0.69{\mu}g{\cdot}cm^{-2}{\cdot}week^{-1}$, which is close to or exceeding the EU Nickel Directive 94/27/EC compensated for the molecular mass of Pd ($0.4{\mu}g{\cdot}cm^{-2}{\cdot}week^{-1}$). The composition of the alloy does not represent the element release, therefore we recommend manufacturers to report element release after ISO standard corrosion tests beside the original composition.

키토산-은나노 복합체가 함유된 의치 연성이장재 특성에 관한 연구 (Characterization of tissue conditioner containing chitosan-doped silver nanoparticles)

  • 남기영;이철재
    • 대한치과보철학회지
    • /
    • 제58권4호
    • /
    • pp.275-281
    • /
    • 2020
  • 목적: 의치 연성이장재 적용기간 경과에 따른 물성저하 및 표면거침성이 의치구내염 발생을 야기할 수 있으며 이 논문의 목적은 항균물질인 키토산-은나노 복합체를 환원법으로 합성하고 이것을 연성이장재에 투여 후 그 특성을 평가하는 것이다. 재료 및 방법: 질산은과 키토산 분말로 혼합 정제된 키토산-은나노 복합체를 자외선 가시광선 및 적외선 분광법으로 분석하고 연성이장재 분말에 각각 0(대조군), 1.0, 3.0 및 5.0의 질량 분율로 첨가 후 단량체 용액과 각각 중합하였다. 항균복합체가 첨가된 연성이장재 시편의 특성은 중합완료 24 시간과 7 일 후 미세인장강도, 은 이온 용출 그리고 색조변화 등을 통하여 각각 평가하였다. 결과: 분광분석을 통하여 안정적인 키토산-은나노 복합체의 합성을 확인하였다. 대조군과 비교 시 복합체첨가에 따른 연성이장재의 유의한 인장강도 변화는 나타내지 않았고 (P > .05) 은 이온 용출은 복합체 투여량에 대하여 농도비례적으로 측정되었으며 색조변화량 또한 농도비례적으로 증가되었다 (P < .05). 결론: 키토산-은나노 복합체가 투여된 연성이장재는 적절한 물성과 은 이온 용출 특성을 가진 보철생체재료의 가능성을 도출하였고 임상 적용을 위한 항균실험 및 색조 안정성 등의 연구들이 추후 필요할 것으로 사료된다.

소아 결핵 진단에 있어서 결핵 특이항원자극 인터페론 감마 측정검사의 임상적 의의 (Clinical Significance of Interferon $\gamma$ Release Assay for Diagnosis of Tuberculosis in Children)

  • 이희우;박화영;안영민;손근찬
    • Pediatric Infection and Vaccine
    • /
    • 제17권2호
    • /
    • pp.137-147
    • /
    • 2010
  • 목적 : 본 연구는 소아에서 QuantiFERON-TB Gold(QTB) 검사의 임상적 유용성과 문제점을 평가하기 위해 시행되었다. 방 법: 2007년 1월부터 2009년 6월까지 본원에서 TST와 QTB를 시행 받은 소아청소년 112명의 의무 기록을 후향적으로 조사하였다. 결과 : TST와 QTB의 양성률은 각각 59.8%, 15.2%였고, 두 검사의 일치도는 낮았다($\kappa$=0.209). QTB의 민감도와 특이도는 각각 80.0%, 92.6%였다. QTB 양성율은 임상적 결핵군, 긴밀 접촉군, 일반 접촉군, 비접촉군에서 각각 80%, 14%, 0%, 2% 였으며, 판정보류의 빈도는 9.8%였다. QTB 추적 관찰이 시행된 환자 중, 초기 QTB 양성이었던 6명 중 5명은 치료 종료 후 평균 2.2개월까지 양성이 지속되었다. 결론 : 소아에서 QTB는 민감도가 낮고, 판정보류의 빈도가 높다는 단점이 있으나, 특이도가 높은 장점이 있으므로, TST의 특이도가 낮은 점을 보완하여 결핵의 진단 및 치료 결정에 활용될 수 있을 것으로 생각된다.

Alterations in uterine hemodynamics caused by uterine fibroids and their impact on in vitro fertilization outcomes

  • Moon, Jei-Won;Kim, Chung-Hoon;Kim, Jun-Bum;Kim, Sung-Hoon;Chae, Hee-Dong;Kang, Byung-Moon
    • Clinical and Experimental Reproductive Medicine
    • /
    • 제42권4호
    • /
    • pp.163-168
    • /
    • 2015
  • Objective: To investigate the impact of fibroids on the blood flow of the uterine and subendometrial arteries and in vitro fertilization (IVF) outcomes. Methods: In this study, we analyzed 86 IVF/intracytoplasmic sperm injection (ICSI) cycles in which a gonadotropin-releasing hormone antagonist protocol was used for controlled ovarian stimulation between January 2008 and March 2009. The subjects comprised 86 infertile women with (fibroid group, n=43) or without (control group, n=43) uterine fibroids. Results: Patient characteristics were similar between the fibroid and control groups. The IVF/ICSI outcomes in patients with fibroids were similar to those of patients in the control group. The resistance index (RI) and pulsatile index (PI) of the uterine and subendometrial arteries on the day of embryo transfer were also comparable between the two groups. IVF outcomes and uterine hemodynamics in patients with multiple (${\geq}2$) fibroids were similar to those of patients with a single fibroid. However, clinical pregnancy and implantation rates were significantly lower in patients with fibroids who experienced uterine cavity distortion than in patients with fibroids who had a normal uterine cavity (both p<0.05). The RI and PI of the subendometrial artery were significantly higher on the day of embryo transfer in patients with fibroids who experienced uterine cavity distortion than in patients with fibroids who had a normal uterine cavity (both p<0.05). Conclusion: Fibroids which distorting the uterine cavity might impair the subendometrial artery blood flow clinical pregnancy rate and embryo implantation rate in infertile patients undergoing IVF. Otherwise, IVF outcomes were not influenced by the presence of uterine fibroids.

A high response to controlled ovarian stimulation induces premature luteinization with a negative impact on pregnancy outcomes in a gonadotropin-releasing hormone antagonist cycle

  • Koo, Hwa Seon;Cha, Sun Hwa;Kim, Hye Ok;Song, In Ok;Min, Eung Gi;Yang, Kwang Moon;Park, Chan Woo
    • Clinical and Experimental Reproductive Medicine
    • /
    • 제42권4호
    • /
    • pp.149-155
    • /
    • 2015
  • Objective: The goal of this study was to investigate the relationship between serum progesterone (P4) levels on the day of human chorionic gonadotropin (hCG) administration and the pregnancy rate among women undergoing controlled ovarian stimulation for in vitro fertilization (IVF) or intracytoplasmic sperm injection-embryo transfer (ICSI-ET) using a flexible antagonist protocol. Methods: This prospective study included 200 IVF and ICSI-ET cycles in which a flexible antagonist protocol was used. The patients were divided into five distinct groups according to their serum P4 levels at the time of hCG administration (0.80, 0.85, 0.90, 0.95, and 1.00 ng/mL). The clinical pregnancy rate (CPR) was calculated for each P4 interval. Statistically significant differences were observed at a serum P4 level of 0.9 ng/mL. These data suggest that a serum P4 concentration of 0.9 ng/mL may represent the optimal threshold level for defining premature luteinization (PL) based on the presence of a significant negative impact on the CPR. Results: The CPR for each round of ET was significantly lower in the PL group defined using this threshold (25.8% vs. 41.8%; p=0.019), and the number of oocytes retrieved was significantly higher than in the non-PL group ($17.3{\pm}7.2$ vs. $11.0{\pm}7.2$; p=0.001). Elevated serum P4 levels on the day of hCG administration were associated with a reduced CPR, despite the retrieval of many oocytes. Conclusion: Measuring serum P4 values at the time of hCG administration is necessary in order to determine the optimal strategy for embryo transfer.

Follicular fluid cerebellin and betatrophin regulate the metabolic functions of growing follicles in polycystic ovary syndrome

  • Ersahin, Aynur Adeviye;Acet, Mustafa;Ersahin, Suat Suphan;Acet, Tuba;Yardim, Meltem;Kenanoglu, Omer;Aydin, Suleyman
    • Clinical and Experimental Reproductive Medicine
    • /
    • 제44권1호
    • /
    • pp.33-39
    • /
    • 2017
  • Objective: The aim of this study was to assess the changes of follicular fluid (FF) and serum levels of cerebellin precursor protein 1 (cbln1) and betatrophin in patients with polycystic ovary syndrome (PCOS) undergoing in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) with a gonadotropin-releasing hormone (GnRH) antagonist protocol. Methods: Twenty infertile women with PCOS and 20 control women diagnosed as poor responders undergoing ovarian stimulation with a GnRH antagonist were included. Blood samples were obtained during ovum pick-up. Follicular fluid from a dominant follicle was collected from the subjects. Using enzyme-linked immunosorbent assays, FF and serum levels of cbln1 and betatrophin were measured in both groups of participants. Metabolic and hormonal parameters were also determined and correlated with each other. Results: Both groups of women had similar serum and FF betatrophin levels ($55.0{\pm}8.9ng/mL$ vs. $53.1{\pm}10.3ng/mL$, p=0.11). The serum and FF betatrophin levels of poor responders were found to be similar ($49.9{\pm}5.9ng/mL$ vs. $48.9{\pm}10.7ng/mL$, p=0.22). Conversely, the FF cbln1 levels of PCOS women were found to be significantly higher than the serum cbln1 levels ($589.1{\pm}147.6ng/L$ vs. $531.7{\pm}74.3ng/L$, p<0.02). The FF cbln1 levels of control participants without PCOS were significantly higher than their serum cbln1 levels ($599.3{\pm}211.5ng/L$ vs. $525.3{\pm}87.0ng/L$, p=0.01). Positive correlations were detected among body mass index, insulin resistance, serum insulin, total testosterone, and betatrophin levels in the PCOS group. Conclusion: Follicular fluid betatrophin and cbln1 concentrations may play a pivotal role on follicular growth in PCOS subjects undergoing IVF/ICSI with an antagonist protocol.

Magnetoresistance of Bi Nanowires Grown by On-Film Formation of Nanowires for In-situ Self-assembled Interconnection

  • Ham, Jin-Hee;Kang, Joo-Hoon;Noh, Jin-Seo;Lee, Woo-Young
    • 한국자기학회:학술대회 개요집
    • /
    • 한국자기학회 2010년도 임시총회 및 하계학술연구발표회
    • /
    • pp.79-79
    • /
    • 2010
  • Semimetallic bismuth (Bi) has been extensively investigated over the last decade since it exhibits very intriguing transport properties due to their highly anisotropic Fermi surface, low carrier concentration, long carrier mean free path l, and small effective carrier mass $m^*$. In particular, the great interest in Bi nanowires lies in the development of nanowire fabrication methods and the opportunity for exploring novel low-dimensional phenomena as well as practical application such as thermoelectricity[1]. In this work, we introduce a self-assembled interconnection of nanostructures produced by an on-film formation of nanowires (OFF-ON) method in order to form a highly ohmic Bi nanobridge. A Bi thin film was first deposited on a thermally oxidized Si (100) substrate at a rate of $40\;{\AA}/s$ by radio frequency (RF) sputtering at 300 K. The sputter system was kept in an ultra high vacuum (UHV) of $10^{-6}$ Torr before deposition, and sputtering was performed under an Ar gas pressure of 2m Torr for 180s. For the lateral growth of Bi nanowires, we sputtered a thin Cr (or $SiO_2$) layer on top of the Bi film. The Bi thin films were subsequently put into a custom-made vacuum furnace for thermal annealing to grow Bi nanowires by the OFF-ON method. After thermal annealing, the Bi nanowires cannot be pushed out from the topside of the Bi films due to the Cr (or $SiO_2$) layer. Instead, Bi nanowires grow laterally as a mean s of releasing the compressive stress. We fabricated a self-assembled Bi nanobridge (d=192 nm) device in-situ using OFF-ON through annealing at $250^{\circ}C$ for 10hours. From I-V measurements taken on the Bi nanobridge device, contacts to the nanobridge were found highly ohmic. The quality of the Bi nanobridge was also proved by the high MR of 123% obtained from transverse MR measurements. These results manifest the possibility of self-assembled nanowire interconnection between various nanostructures for a variety of applications and provide a simple device fabrication method to investigate transport properties on nanowires without complex patterning and etching processes.

  • PDF

Factors Predicting Early Release of Thyroid Cancer Patients from the Isolation Room after Radioiodine-131 Treatment

  • Fatima, Nosheen;Zaman, Maseeh uz;Zaman, Areeba;Zaman, Unaiza;Tahseen, Rabia;Shahid, Wajiha
    • Asian Pacific Journal of Cancer Prevention
    • /
    • 제17권1호
    • /
    • pp.125-129
    • /
    • 2016
  • Background: Patients with differentiated thyroid cancers (DTC) who receive radioactive iodine-131 (RAI) are released from isolation when their dose rate is below the regulatory requirements. The purpose of this study was establish predicting factors for early release from the isolation facility after RAI administration in patients with DTC. Materials and Methods: This was a prospective study which included 96 (58 females and 38 males) patients with DTC who had received RAI from April 2013 till August 2015. The study was duly approved by the ethical committee of the institute. Patients who had complete information of primary tumor size (PTS), serum TSH, stimulated thyroglobulin level [sTg] with antibodies (IU/ml) at the time of RAI treatment were included. All had a normal serum creatinine level. To attain lower effective half-life good hydration and administration of soft laxative were ensured. Dose rate was measured (immediately, 24 h and 36 h) at 1 meter distance from anterior mid trunk and a dose rate <$50{\mu}Sv/h$ was considered as the releasing criterion. At 24 h 50 patients were released while the remaining 46 patients were released at 36 h. A post-ablative whole body scan (PA-WBIS) was performed 5-8 days after RAI ablation in all patients. Results: Patients released after 24 h were significantly younger, had smaller lesions with higher proportion of papillary cancer, lower sTg, lower sTg/TSH ratio and had received a lower dose of RAI as comapred to those who were discharged after 36 h. Serum TSH and gender were not found to have any significant correlation between two cohorts. ROC and multivariate analysis have shown age ${\leq}37years$, PTS ${\leq}3.8cm$, $RAI{\leq}150mCi$, $sTg{\leq}145ng/ml$ and $sTg/TSH{\leq}1.085$ as strong indepedent predictors for early release. Conclusions: We conclude that younger age (${\leq}37years$), smaller tumor size (${\leq}3.8cm$), lower RAI dose (${\leq}150mCi$), lower sTg (${\leq}145ng/ml$) and a lower sTg/TSH ratio (${\leq}1.085$) are significant independent predictors for release at 24 h after RAI treatment in DTC patients. Effective utilization of these factors could help the treating physicians to use limited number of internment facilities with higher throughput, lower cost and lower psychological stress to patients.

Deoxynivalenol- and zearalenone-contaminated feeds alter gene expression profiles in the livers of piglets

  • Reddy, Kondreddy Eswar;Jeong, Jin young;Lee, Yookyung;Lee, Hyun-Jeong;Kim, Min Seok;Kim, Dong-Wook;Jung, Hyun Jung;Choe, Changyong;Oh, Young Kyoon;Lee, Sung Dae
    • Asian-Australasian Journal of Animal Sciences
    • /
    • 제31권4호
    • /
    • pp.595-606
    • /
    • 2018
  • Objective: The Fusarium mycotoxins of deoxynivalenol (DON) and zerolenone (ZEN) cause health hazards for both humans and farm animals. Therefore, the main intention of this study was to reveal DON and ZEN effects on the mRNA expression of pro-inflammatory cytokines and other immune related genes in the liver of piglets. Methods: In the present study, 15 six-week-old piglets were randomly assigned to the following three different dietary treatments for 4 weeks: control diet, diet containing 8 mg DON/kg feed, and diet containing 0.8 mg ZEN/kg feed. After 4 weeks, liver samples were collected and sequenced using RNA-Seq to investigate the effects of the mycotoxins on genes and gene networks associated with the immune systems of the piglets. Results: Our analysis identified a total of 249 differentially expressed genes (DEGs), which included 99 upregulated and 150 downregulated genes in both the DON and ZEN dietary treatment groups. After biological pathway analysis, the DEGs were determined to be significantly enriched in gene ontology terms associated with many biological pathways, including immune response and cellular and metabolic processes. Consistent with inflammatory stimulation due to the mycotoxin-contaminated diet, the following Kyoto encyclopedia of genes and genomes pathways, which were related to disease and immune responses, were found to be enriched in the DEGs: allograft rejection pathway, cell adhesion molecules, graft-versus-host disease, autoimmune thyroid disease (AITD), type I diabetes mellitus, human T-cell leukemia lymphoma virus infection, and viral carcinogenesis. Genome-wide expression analysis revealed that DON and ZEN treatments downregulated the expression of the majority of the DEGs that were associated with inflammatory cytokines (interleukin 10 receptor, beta, chemokine [C-X-C motif] ligand 9), proliferation (insulin-like growth factor 1, major facilitator superfamily domain containing 2A, insulin-like growth factor binding protein 2, lipase G, and salt inducible kinase 1), and other immune response networks (paired immunoglobulin-like type 2 receptor beta, Src-like-adaptor-1 [SLA1], SLA3, SLA5, SLA7, claudin 4, nicotinamide N-methyltransferase, thyrotropin-releasing hormone degrading enzyme, ubiquitin D, histone $H_2B$ type 1, and serum amyloid A). Conclusion: In summary, our results demonstrated that high concentrations DON and ZEN disrupt immune-related processes in the liver.

인테그린 α2와 상피성장인자수용체 차단항체의 저해작용을 통한 구강편평상피암 세포의 선택적 제거 (Induction of Selective Cell Death of Oral Squamous Carcinoma Cells by Integrin α2 Antibody and EGFR Antibody)

  • 최연식;김규천;윤식;황대석;김철훈;전영찬;변준호;신상훈;김욱규
    • Maxillofacial Plastic and Reconstructive Surgery
    • /
    • 제35권3호
    • /
    • pp.143-154
    • /
    • 2013
  • Purpose: This study was to find efficacy of integrin alpha2 (${\alpha}_2$) and epidermal growth factor receptor (EGFR) as tumor marker of oral squamous cell carcinoma (SCC) and clarify the selective cell death effect of anti-integrin ${\alpha}_2$ and anti-EGFR on SCC cells, additionally testify conjugated gold nanoparticles (GNP) with air plasma for selective cell death of oral SCC. Methods: Expression of integrin ${\alpha}_2$, EGFR on human SCC cells (SCC25) were examined by western blot. SCC25 cells were treated with anti-integrin ${\alpha}_2$, anti-EGFR and analysed by Hemacolor staining, immunoflorescence staining, FACS flow cytometry. Conjugated GNP with integrin ${\alpha}_2$, EGFR antibody were treated by air plasma on SCC cells. Results: Integrin ${\alpha}_2$ and EGFR were over-expressed on SCC25 cells than normal lung WI-38 cells. The cell viability rate of SCC25 cells treated with anti-integrin ${\alpha}_2$, anti-EGFR was lower than WI-38 cells. The concentration changes of nucleus, releasing cytochrome c and apoptosis inducing factor (AIF) from mitochondria to cytosol were observed. The changes of proteins related with apoptosis were observed. Increase of bax, bcl-xL, activation of caspase-3, -7, -9, and fragmentation of PARP, DFF45 and decrease of lamin A/C in SCC25 cells were observed. In FACS, increase of sub-$G_1$ and S phase was observed. Cell cycle related proteins, Such as cyclin D1, cyclin dependent kinase (CDK) 4, cyclin A, cyclin E, CDK 2, p27 were decreased. After SCC25 cells treated with conjugatged GNP-Integrin ${\alpha}_2$, GNP-EGFR, additionally air plasma, the cell death rate was significantly increased. Conclusion: Integrin ${\alpha}_2$, EGFR were over-expressed in oral SCC cells. Anti-integrin ${\alpha}_2$, anti-EGFR in SCC25 cells induced apoptosis selectively. When GNP-anti integrin ${\alpha}_2$, GNP-anti EGFR were treated with air plasma on SCC25 cells, cancer cells were died more selectively. GNP-anti integrin ${\alpha}_2$, GNP-anti EGFR with air plasma could be treatment choice of oral SCC.