• 제목/요약/키워드: Selective Search

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A comparative review of epinephrine and phenylephrine as vasoconstrictors in dental anesthesia: exploring the factors behind epinephrine's prevalence in the US

  • Navkiran Deol;Gerardo Alvarez;Omar Elrabi;Gavin Chen;Nalton Ferraro
    • Journal of Dental Anesthesia and Pain Medicine
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    • 제23권6호
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    • pp.293-302
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    • 2023
  • This review paper delves into the comparative study of epinephrine and phenylephrine as vasoconstrictors in dental anesthesia, exploring their histories, pharmacological properties, and clinical applications. The study involved a comprehensive literature search, focusing on articles that directly compared the two agents in terms of efficacy, safety, and prevalence in dental anesthesia. Epinephrine, with its broad receptor profile, has been a predominant choice, slightly outperforming in the context of prolonging dental anesthesia and providing superior hemostasis, which is crucial for various dental procedures. However, the stimulation of beta-adrenergic receptors caused by epinephrine poses risks, especially to patients with cardiovascular conditions. Phenylephrine, a selective alpha-1 adrenergic agonist, emerges as a safer alternative for such patients, avoiding the cardiovascular risks associated with epinephrine. Moreover, its vasoconstrictive effect may not be as deleterious as that of epinephrine, due to its selective action. This review reveals that despite the potential benefits of phenylephrine, epinephrine continues to dominate in clinical settings, due to its historical familiarity, availability, and cost-effectiveness. The lack of commercially available pre-made phenylephrine dental carpules in most countries, except Brazil, and a knowledge gap within dental academia regarding phenylephrine, contribute to its limited use. This review concludes that while both agents are effective, the choice between them should be based on individual patient conditions, availability, and the practitioner's knowledge and familiarity with the agents. The underuse of other vasoconstrictors like levonordefrin and the unavailability of phenylephrine in pre-mixed dental cartridges in many countries highlights the need for further exploration and research in this field. Furthermore, we also delve into the role of levonordefrin and examine the rationale behind the exclusion of phenylephrine from commercially available pre-mixed local anesthetic carpules, suggesting a need for a responsive approach from pharmaceutical manufacturers to the distinct needs of the dental community.

Inhibition of matrix metalloproteinases: a troubleshooting for dentin adhesion

  • de Moraes, Izadora Quintela Souza;do Nascimento, Ticiano Gomes;da Silva, Antonio Thomas;de Lira, Lilian Maria Santos Silva;Parolia, Abhishek;de Moraes Porto, Isabel Cristina Celerino
    • Restorative Dentistry and Endodontics
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    • 제45권3호
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    • pp.31.1-31.20
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    • 2020
  • Matrix metalloproteinases (MMPs) are enzymes that can degrade collagen in hybrid layer and reduce the longevity of adhesive restorations. As scientific understanding of the MMPs has advanced, useful strategies focusing on preventing these enzymes' actions by MMP inhibitors have quickly developed in many medical fields. However, in restorative dentistry, it is still not well established. This paper is an overview of the strategies to inhibit MMPs that can achieve a long-lasting material-tooth adhesion. Literature search was performed comprehensively using the electronic databases: PubMed, ScienceDirect and Scopus including articles from May 2007 to December 2019 and the main search terms were "matrix metalloproteinases", "collagen", and "dentin" and "hybrid layer". MMPs typical structure consists of several distinct domains. MMP inhibitors can be divided into 2 main groups: synthetic (synthetic-peptides, non-peptide molecules and compounds, tetracyclines, metallic ions, and others) and natural bioactive inhibitors mainly flavonoids. Selective inhibitors of MMPs promise to be the future for specific targeting of preventing dentin proteolysis. The knowledge about MMPs functionality should be considered to synthesize drugs capable to efficiently and selectively block MMPs chemical routes targeting their inactivation in order to overcome the current limitations of the therapeutic use of MMPs inhibitors, i.e., easy clinical application and long-lasting effect.

The Prediction of the Expected Current Selection Coefficient of Single Nucleotide Polymorphism Associated with Holstein Milk Yield, Fat and Protein Contents

  • Lee, Young-Sup;Shin, Donghyun;Lee, Wonseok;Taye, Mengistie;Cho, Kwanghyun;Park, Kyoung-Do;Kim, Heebal
    • Asian-Australasian Journal of Animal Sciences
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    • 제29권1호
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    • pp.36-42
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    • 2016
  • Milk-related traits (milk yield, fat and protein) have been crucial to selection of Holstein. It is essential to find the current selection trends of Holstein. Despite this, uncovering the current trends of selection have been ignored in previous studies. We suggest a new formula to detect the current selection trends based on single nucleotide polymorphisms (SNP). This suggestion is based on the best linear unbiased prediction (BLUP) and the Fisher's fundamental theorem of natural selection both of which are trait-dependent. Fisher's theorem links the additive genetic variance to the selection coefficient. For Holstein milk production traits, we estimated the additive genetic variance using SNP effect from BLUP and selection coefficients based on genetic variance to search highly selective SNPs. Through these processes, we identified significantly selective SNPs. The number of genes containing highly selective SNPs with p-value <0.01 (nearly top 1% SNPs) in all traits and p-value <0.001 (nearly top 0.1%) in any traits was 14. They are phosphodiesterase 4B (PDE4B), serine/threonine kinase 40 (STK40), collagen, type XI, alpha 1 (COL11A1), ephrin-A1 (EFNA1), netrin 4 (NTN4), neuron specific gene family member 1 (NSG1), estrogen receptor 1 (ESR1), neurexin 3 (NRXN3), spectrin, beta, non-erythrocytic 1 (SPTBN1), ADP-ribosylation factor interacting protein 1 (ARFIP1), mutL homolog 1 (MLH1), transmembrane channel-like 7 (TMC7), carboxypeptidase X, member 2 (CPXM2) and ADAM metallopeptidase domain 12 (ADAM12). These genes may be important for future artificial selection trends. Also, we found that the SNP effect predicted from BLUP was the key factor to determine the expected current selection coefficient of SNP. Under Hardy-Weinberg equilibrium of SNP markers in current generation, the selection coefficient is equivalent to $2^*SNP$ effect.

Quantum Mechanical Simulation for the Analysis, Optimization and Accelerated Development of Precursors and Processes for Atomic Layer Deposition (ALD)

  • Mustard, Thomas Jeffrey Lomax;Kwak, Hyunwook Shaun;Goldberg, Alexander;Gavartin, Jacob;Morisato, Tsuguo;Yoshidome, Daisuke;Halls, Mathew David
    • 한국세라믹학회지
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    • 제53권3호
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    • pp.317-324
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    • 2016
  • Continued miniaturization and increasingly exact requirements for thin film deposition in the semiconductor industry is driving the search for new effective, efficient, selective precursors and processes. The requirements of defect-free, conformal films, and precise thickness control have focused attention on atomic layer deposition (ALD). ALD precursors so far have been developed through a trial-and-error experimental approach, leveraging the expertise and tribal knowledge of individual research groups. Precursors can show significant variation in performance, depending on specific choice of co-reactant, deposition stage, and processing conditions. The chemical design space for reactive thin film precursors is enormous and there is urgent need for the development of computational approaches to help identify new ligand-metal architectures and functional co-reactants that deliver the required surface activity for next-generation thin-film deposition processes. In this paper we discuss quantum mechanical simulation (e.g. density functional theory, DFT) applied to ALD precursor reactivity and state-of-the-art automated screening approaches to assist experimental efforts leading toward optimized precursors for next-generation ALD processes.

Joint Transmitter and Receiver Optimization for Improper-Complex Second-Order Stationary Data Sequence

  • Yeo, Jeongho;Cho, Joon Ho;Lehnert, James S.
    • Journal of Communications and Networks
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    • 제17권1호
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    • pp.1-11
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    • 2015
  • In this paper, the transmission of an improper-complex second-order stationary data sequence is considered over a strictly band-limited frequency-selective channel. It is assumed that the transmitter employs linear modulation and that the channel output is corrupted by additive proper-complex cyclostationary noise. Under the average transmit power constraint, the problem of minimizing the mean-squared error at the output of a widely linear receiver is formulated in the time domain to find the optimal transmit and receive waveforms. The optimization problem is converted into a frequency-domain problem by using the vectorized Fourier transform technique and put into the form of a double minimization. First, the widely linear receiver is optimized that requires, unlike the linear receiver design with only one waveform, the design of two receive waveforms. Then, the optimal transmit waveform for the linear modulator is derived by introducing the notion of the impropriety frequency function of a discrete-time random process and by performing a line search combined with an iterative algorithm. The optimal solution shows that both the periodic spectral correlation due to the cyclostationarity and the symmetric spectral correlation about the origin due to the impropriety are well exploited.

Efficient LDPC-Based, Threaded Layered Space-Time-Frequency System with Iterative Receiver

  • Hu, Junfeng;Zhang, Hailin;Yang, Yuan
    • ETRI Journal
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    • 제30권6호
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    • pp.807-817
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    • 2008
  • We present a low-density parity-check (LDPC)-based, threaded layered space-time-frequency system with emphasis on the iterative receiver design. First, the unbiased minimum mean-squared-error iterative-tree-search (U-MMSE-ITS) detector, which is known to be one of the most efficient multi-input multi-output (MIMO) detectors available, is improved by augmentation of the partial-length paths and by the addition of one-bit complement sequences. Compared with the U-MMSE-ITS detector, the improved detector provides better detection performance with lower complexity. Furthermore, the improved detector is robust to arbitrary MIMO channels and to any antenna configurations. Second, based on the structure of the iterative receiver, we present a low-complexity belief-propagation (BP) decoding algorithm for LDPC-codes. This BP decoder not only has low computing complexity but also converges very fast (5 iterations is sufficient). With the efficient receiver employing the improved detector and the low-complexity BP decoder, the proposed system is a promising solution to high-data-rate transmission over selective-fading channels.

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A Qualitative Study on Risk Reduction Behaviors in Purchase Process of the Counterfeit of Fashion Luxury Brands - Focused on Risk Reduction Behaviors on Psychological Risk Perceptions -

  • Kim, Il
    • 패션비즈니스
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    • 제9권3호
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    • pp.22-36
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    • 2005
  • This research is to classify psychological risk perceptions in purchases process at counterfeit at fashion luxury brands, into a risk perception on purchase activity itself and a risk perception on the post-purchase situation, and to analyze types and characteristics at risk reduction behaviors to reduce each risk perception. In this research a qualitative method was employed, and research-related data were collected and analyzed through in-depth interviews. Results were shown that risk reduction behaviors at psychological risk perception on purchase activity itself included rationalization of purchase, accompanied purchase, reduction and discontinuance of purchase, and that risk reduction behaviors of psychological risk perception on the post-purchase situation included information search, establishment of selection criteria, establishment of marginal limit, selective purchase, planned and compared purchase, and reduction and discontinuance of purchase. Previous researches suggested brand loyalty, selection of famous brands, utilization of information agents by marketers, pre-purchase usage and guaranteed purchase, but these risk reduction methods were not utilized, this probably being interpreted as a result of characteristics of counterfeit. In addition, risk reduction behavior of one type tended to reduce risk perception of several other types, and risk reduction behaviors of various types were utilized to reduce a certain type's risk perception. Not only types of risk perception but also levels of risk perception appeared to have exerted influence to risk reduction behaviors.

Signal Transduction Network Leading to COX-2 Induction: A Road Map in Search of Cancer Chemopreventives

  • Surh Young-Joon;Kundu Joydeb Kumar
    • Archives of Pharmacal Research
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    • 제28권1호
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    • pp.1-15
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    • 2005
  • Cancer is still a major global health concern even after an everlasting strive in conquering this dread disease. Emphasis is now given to chemoprevention to reduce the risk of cancer and also to improve the quality of life among cancer afflicted individuals. Recent progress in molecular biology of cancer has identified key components of the cellular signaling network, whose functional abnormality results in undesired alterations in cellular homeostasis, creating a cellular microenvironment that favors premalignant and malignant transformation. Multiple lines of evidence suggest an elevated expression of cyclooxygenase-2 (COX-2) is causally linked to cancer. In response to oxidative/pro-inflammatory stimuli, turning on unusual signaling arrays mediated through diverse classes of kinases and transcription factors results in aberrant expression of COX-2. Population-based as well as laboratory studies have explored a broad spectrum of chemopreventive agents including selective COX-2 inhibitors and a wide variety of anti-inflammatory phytochemicals, which have been shown to target cellular signaling molecules as underlying mechanisms of chemoprevention. Thus, unraveling signaling pathways regulating aberrant COX-2 expression and targeted blocking of one or more components of those signal cascades may be exploited in searching chemopreventive agents in the future.

A Novel PPARγ Agonist, SP1818, Shows Different Coactivator Profile with Rosiglitazone

  • Park, Yun-Sun;Choi, Ji-Won;Kim, Kun-Yong;Lim, Jong-Seok;Yoon, Suk-Joon;Yang, Young
    • Biomolecules & Therapeutics
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    • 제18권1호
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    • pp.77-82
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    • 2010
  • Peroxisome proliferator-activated receptor $\gamma$ (PPAR${\gamma}$) is a ligand-activated transcription factor that is used as a target for anti-diabetic drug development. In a search for novel PPAR${\gamma}$ agonists, the $\beta$-carboxyethyl-rhodanine derivative SP1818 was identified. We report here the characteristics of SP1818 as a selective PPAR${\gamma}$ agonist. In transactivation assays, SP1818 selectively activated PPAR${\gamma}$, but the degree of PPAR${\gamma}$ stimulation was less than with $1{\mu}M$ rosiglitazone. SP1818 also stimulated glucose uptake in a concentration-dependent manner. The adipocyte differentiation markers adiponectin, scavenger receptor CD36 and aP2 were weakly induced by treatment with SP1818, and TRAP220 subunit was specifically recruited into PPAR${\gamma}$ activated by rosiglitazone but not PPAR${\gamma}$ activated by SP1818.

호텔 레스토랑 고객의 특성, 이용 목적 및 준거 집단에 따른 선택 속성과 만족도에 미치는 영향 (The Effect on Selective Attribute and Satisfaction by Customer's Characteristics, Use and Reference Group for Hotel Restaurants)

  • 전진화;박광용;김종필
    • 한국조리학회지
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    • 제13권3호
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    • pp.220-238
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    • 2007
  • This study investigates the importance of customers who use hotel restaurants on the basis of literature and actual data, establishes positioning strategies to stimulate hotel restaurants amidst an intensely competitive market, and sets up marketing strategies that can be applied to hotel restaurant business from the analysis results. Determinant factors for hotel restaurants were service quality, food, atmosphere and cleanness, brand and reputation, the attitude and appearance of attendants, and variety of menu, in the order of importance. As for the analysis results for satisfaction, the higher the customers regarded on the attitude and appearance of attendants and the food of the restaurant, the higher the overall satisfaction, the intention of revisiting, and the intention of recommendation of the customers became. Therefore, the marketing and promotion staffs of hotel restaurants should search for the ways to meet these needs of customers as much as possible, and identify the usage inclinations and satisfaction level of customers when carrying out marketing activities and establishing customer relationship marketing strategies.

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