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1.
Sensors (Basel) ; 21(11)2021 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-34073896

RESUMO

Recent advances in nanomaterials technology create the new possibility to fabricate high performance sensors. However, there has been limitations in terms of multivariate measurable and interoperable sensors. In this study, we fabricated an interoperable silver nanoparticle sensor fabricated by an aerodynamically focused nanomaterial (AFN) printing system which is a direct printing technique for inorganic nanomaterials onto a flexible substrate. The printed sensor exhibited the maximum measurable frequency of 850 Hz, and a gauge factor of 290.62. Using a fabricated sensor, we evaluated the sensing performance and demonstrated the measurement independency of strain and vibration sensing. Furthermore, using the proposed signal separation algorithm based on the Kalman filter, strain and vibration were each measured in real time. Finally, we applied the printed sensor to quadrotor condition monitoring to predict the motion of a quadrotor.

2.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-894149

RESUMO

Background@#Pembrolizumab, an anti-cancer drug, is known to increase the activity of the immune system, leading to side effects called immune-related adverse events (irAE), including type 1 diabetes. This study analyzed the correlation between blood glucose level and pembrolizumab administration and investigated the covariates that affect those changes in cancer treatment. @*Methods@#The information of 133 adult cancer patients was obtained from the electronic medical record (EMR) to identify the changes in random blood glucose (RBG) levels during the pembrolizumab treatment. Subjects were classified into subgroups according to their baseline RBG level, history of diabetes, and the use of steroids, and linear regression analysis was conducted. In addition, a secondary analysis was performed within the group of subjects having a strong correlation to glycemic change, which was based on the Pearson correlation coefficient being less than -0.7 or greater than +0.7. Univariate and multivariate logistic regressions were conducted to identify the risk factors to glycemic increase. @*Results@#The RBG level tended to descend without significant differences in total patients during the administration period of pembrolizumab. Despite the insignificance, the logistic regression analysis presents that the odds ratios of baseline RBG less than 130 mg/dL, prophylactic steroid use, and higher dose of pembrolizumab per cycle (mg/kg/ cycle) were greater than 1. @*Conclusions@#Prophylactic administration of steroids and a higher dose of pembrolizumab per cycle may increase the blood glucose level as irAE in cancer patients with a strong tendency to glycemic change.

3.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-901853

RESUMO

Background@#Pembrolizumab, an anti-cancer drug, is known to increase the activity of the immune system, leading to side effects called immune-related adverse events (irAE), including type 1 diabetes. This study analyzed the correlation between blood glucose level and pembrolizumab administration and investigated the covariates that affect those changes in cancer treatment. @*Methods@#The information of 133 adult cancer patients was obtained from the electronic medical record (EMR) to identify the changes in random blood glucose (RBG) levels during the pembrolizumab treatment. Subjects were classified into subgroups according to their baseline RBG level, history of diabetes, and the use of steroids, and linear regression analysis was conducted. In addition, a secondary analysis was performed within the group of subjects having a strong correlation to glycemic change, which was based on the Pearson correlation coefficient being less than -0.7 or greater than +0.7. Univariate and multivariate logistic regressions were conducted to identify the risk factors to glycemic increase. @*Results@#The RBG level tended to descend without significant differences in total patients during the administration period of pembrolizumab. Despite the insignificance, the logistic regression analysis presents that the odds ratios of baseline RBG less than 130 mg/dL, prophylactic steroid use, and higher dose of pembrolizumab per cycle (mg/kg/ cycle) were greater than 1. @*Conclusions@#Prophylactic administration of steroids and a higher dose of pembrolizumab per cycle may increase the blood glucose level as irAE in cancer patients with a strong tendency to glycemic change.

4.
Materials (Basel) ; 13(13)2020 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-32610552

RESUMO

A real-time, accurate, and reliable process monitoring is a basic and crucial enabler of intelligent manufacturing operation and digital twin applications. In this study, we represent a novel vibration measurement method for workpiece during the milling process using a low-cost nanoparticle vibration sensor. We directly printed the vibration sensor based on silver nanoparticles positioned onto a polyimide substrate using an aerodynamically-focused nanomaterials printing system, which is a direct printing technique for inorganic nanomaterials positioned onto a flexible substrate. Since it does not require any post-process such as chemical etching and heat treatment, a highly sensitive vibration sensor composed of a microscale porous structure was fabricated at a cost of several cents each. Furthermore, accurate and reliable vibration data was obtained by simple and direct attachment to a workpiece. In this study, we discussed the performance of vibration measurement of a fabricated sensor in comparison to a commercial vibration sensor. Using frequency and power spectrum analysis of obtained data, we directly measured the vibration of workpiece during the milling process, according to a process parameter. Lastly, we applied a fabricated sensor for the digital twins of turbine blade manufacturing in which vibration greatly affects the quality of the product to predict the process defects in real-time.

5.
ACS Nano ; 14(5): 5392-5399, 2020 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-32275387

RESUMO

Structural colors that can be changed dynamically, using either plasmonic nanostructures or photonic crystals, are rapidly emerging research areas for stretchable sensors. Despite the wide applications of various techniques to achieve strain-responsive structural colors, important factors in the feasibility of strain sensors-such as their sensing mechanism, stability, and reproducibility-have not yet been explored. Here, we introduce a stretchable, diffractive, color-based wireless strain sensor that can measure strain using the entire visible spectrum, based on an array of cone-shaped nanostructures on the surface of an elastomeric substrate. By stretching or compressing the substrate, the diffractive color can be tuned according to the changing grating pitch. Using the proposed method, we designed three types of strain-sensing modes: large-deformation (maximum 100%) tensile strain, biaxial 2D strain, and shear strain (maximum 78%). The strain sensors were fabricated, and applicability to strain-sensing was evaluated.

6.
ACS Appl Mater Interfaces ; 11(29): 26421-26432, 2019 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-31148453

RESUMO

We developed and presented highly sensitive solvent-free silver nanoparticle strain sensors fabricated using the aerodynamically focused nanoparticle (AFN) printer. The nanoparticles were printed in various conductive patterns. We explored how printer scan velocity affected pattern geometry and sensor sensitivity. The strain sensors were highly sensitive; the scan velocity afforded tunable sensitivity; and an analytical model predicted the behavior well under low-strain (<0.4%) conditions. We describe a prototype sensor that reliably measured composite beam tensile strain. We further enhanced the sensitivity by creating mechanical cracks, facilitating small dynamic signal measurements. The linear sensitivity of the sensor could be tuned from 18.60 to 290.62 by varying the scan velocity from 2 to 40 µm/s. The cracked sensor afforded the greatest sensitivity (1056) and captured small vibrations from a stringed instrument. We report highly sensitive and reliable measurements of dynamic behavior with simple tunability.

7.
Biochem Biophys Res Commun ; 391(1): 1080-6, 2010 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-20004647

RESUMO

Neutrophils and monocytes are abundantly represented in the synovial fluid and tissue in rheumatoid arthritis patients. We therefore explored the effects of small molecule chemokine receptor antagonists to block migration of these cells in anti-collagen antibody-induced arthritis. Targeting neutrophil migration with the CXCR2/CXCR1 antagonist SCH563705 led to a dose-dependent decrease in clinical disease scores and paw thickness measurements and clearly reduced inflammation and bone and cartilage degradation based on histopathology and paw cytokine analyses. In contrast, targeting monocyte migration with the CCR2 antagonist MK0812 had no effect on arthritis disease severity. The pharmacodynamic activities of both SCH563705 and MK0812 were verified by assessing their effects on the peripheral blood monocyte and neutrophil populations. SCH563705 selectively reduced the peripheral blood neutrophil frequency, and caused an elevation in the CXCR2 ligand CXCL1. MK0812 selectively reduced the peripheral blood monocyte frequency, and caused an elevation in the CCR2 ligand CCL2. The much greater impact of CXCR2/CXCR1 antagonism relative to CCR2 antagonism in this model of arthritis highlights the therapeutic potential for targeting CXCR2/CXCR1 in human arthritides.


Assuntos
Artrite Reumatoide/imunologia , Movimento Celular/efeitos dos fármacos , Neutrófilos/efeitos dos fármacos , Receptores CCR2/antagonistas & inibidores , Receptores de Interleucina-8B/antagonistas & inibidores , Animais , Modelos Animais de Doenças , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Neutrófilos/imunologia , Receptores CCR2/fisiologia , Receptores de Interleucina-8B/fisiologia , Líquido Sinovial/efeitos dos fármacos , Líquido Sinovial/imunologia
8.
J Inflamm (Lond) ; 6: 32, 2009 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-19906300

RESUMO

BACKGROUND: CCR2 plays a key role in regulating monocyte trafficking to sites of inflammation and therefore has been the focus of much interest as a target for inflammatory disease. METHODS: Here we examined the effects of CCR2 blockade with a potent small molecule antagonist to determine the pharmacodynamic consequences on the peripheral blood monocyte compartment in the context of acute and chronic inflammatory processes. RESULTS: We demonstrate that CCR2 antagonism in vivo led to a rapid decrease in the number of circulating Ly6Chi monocytes and that this decrease was largely due to the CXCR4-dependent sequestration of these cells in the bone marrow, providing pharmacological evidence for a mechanism by which monocyte dynamics are regulated in vivo. CCR2 antagonism led to an accumulation of circulating CCL2 and CCL7 levels in the blood, indicating a role for CCR2 in regulating the levels of its ligands under homeostatic conditions. Finally, we show that the pharmacodynamic changes due to CCR2 antagonism were apparent after chronic dosing in mouse experimental autoimmune encephalomyelitis, a model in which CCR2 blockade demonstrated a dramatic reduction in disease severity, manifest in a reduced accumulation of monocytes and other cells in the CNS. CONCLUSION: CCR2 antagonism in vivo has tractable pharmacodynamic effects that can be used to align target engagement with biologic effects on disease activity.

9.
Reprod Biol Endocrinol ; 7: 47, 2009 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-19450261

RESUMO

BACKGROUND: Female mice and rats injected with estrogen perinatally become anovulatory and develop follicular cysts. The current consensus is that this adverse response to estrogen involves the hypothalamus and occurs because of an estrogen-induced alteration in the GnRH delivery system. Whether or not this is true has yet to be firmly established. The present study examined an alternate possibility in which anovulation and cyst development occurs through an estrogen-induced disruption in the immune system, achieved through the intermediation of the thymus gland. METHODS, RESULTS AND CONCLUSION: A putative role for the thymus in estrogen-induced anovulation and follicular cyst formation (a model of PCOS) was examined in female mice by removing the gland prior to estrogen injection. Whereas all intact, female mice injected with 20 microg estrogen at 5-7 days of age had ovaries with follicular cysts, no cysts were observed in animals in which thymectomy at 3 days of age preceded estrogen injection. In fact, after restoring immune function by thymocyte replacement, the majority of thymectomized, estrogen-injected mice had ovaries with corpora lutea. Thus, when estrogen is unable to act on the thymus, ovulation occurs and follicular cysts do not develop. This implicates the thymus in the cysts' genesis and discounts the role of the hypothalamus. Subsequent research established that the disease is transferable by lymphocyte infusion. Transfer took place between 100-day-old estrogen-injected and 15-day-old naïve mice only when recipients were thymectomized at 3 days of age. Thus, a prerequisite for cyst formation is the absence of regulatory T cells. Their absence in donor mice was judged to be the result of an estrogen-induced increase in the thymus' vascular permeability, causing de facto circumvention of the final stages of regulatory T cell development. The human thymus has a similar vulnerability to steroid action during the fetal stage. We propose that in utero exposure to excessive levels of steroids such as estrogen has a long-term effect on the ability of the thymus to produce regulatory T cells. In female offspring this can lead to PCOS.


Assuntos
Anovulação , Estrogênios/toxicidade , Síndrome do Ovário Policístico , Fatores Etários , Animais , Animais Recém-Nascidos , Anovulação/induzido quimicamente , Anovulação/etiologia , Anovulação/imunologia , Autoimunidade/efeitos dos fármacos , Autoimunidade/imunologia , Modelos Animais de Doenças , Feminino , Hidrocortisona/toxicidade , Hipotálamo/efeitos dos fármacos , Hipotálamo/fisiologia , Injeções Subcutâneas , Camundongos , Camundongos Endogâmicos A , Camundongos Endogâmicos C57BL , Síndrome do Ovário Policístico/induzido quimicamente , Síndrome do Ovário Policístico/etiologia , Síndrome do Ovário Policístico/imunologia , Testosterona/toxicidade , Timectomia , Timo/efeitos dos fármacos , Timo/imunologia , Timo/cirurgia
10.
J Hazard Mater ; 154(1-3): 933-45, 2008 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-18082325

RESUMO

Batch leach tests (BLTs) and column leach tests (CLTs) were conducted on bottom ash (BA), lagoon ash (LA), soil (S), and bottom ash-soil (BA-S) and lagoon ash-soil (LA-S) mixtures to evaluate the environmental feasibility of using these as fill materials to raise the ground level at construction sites. For the BLTs, the leachability of the elements (i.e., Cr, Mn, Ni, and Zn) generally increased with decreasing pH from 6.3 to 3.0. In addition, the concentration of all the elements analyzed in the leachates increased with decreasing the liquid-to-solid (L/S) ratio. Freezing-thawing cycles had no significant effect on the leachability of the elements found in the BLTs. The initial concentrations of the leachates from the CLTs were higher than those of the leachates from the BLTs regardless of the materials tested due to the lower L/S ratio. The initial concentrations of As, Ni, Mn, Se, Cl-, and SO4(2-) in the leachates from the CLTs for the LA, BA, and LA-S and BA-S mixtures exceeded the drinking water standards (DWSs), which suggests that these materials may pose a risk to groundwater when these materials are used in areas where there is little dilution.


Assuntos
Carvão Mineral , Resíduos Industriais/análise , Centrais Elétricas , Poluentes do Solo/análise , Poluentes Químicos da Água/análise , Congelamento , Concentração de Íons de Hidrogênio , Solo/análise , Poluentes do Solo/toxicidade , Gerenciamento de Resíduos/métodos , Poluentes Químicos da Água/toxicidade
11.
Bioresour Technol ; 99(3): 626-30, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17336059

RESUMO

Biomass-based adsorbents have been widely studied as a cost-effective and environmentally-benign means to remove pollutants and nutrients from water. A two-stage treatment of aspen wood particles with solutions of carboxymethyl cellulose (CMC) and ferrous chloride afforded a biosorbent that was effective in removing phosphate from test solutions. FTIR spectroscopy of the biosorbent samples showed a decrease in the intensity of the carboxylate signal coinciding with a decrease in particle size. Elemental analysis results showed the iron content of both the biosorbent samples, and wood particles treated with ferrous chloride alone, to also decrease with particle size. The relationship between iron content and particle size for the biosorbent samples appeared to be a function of both the amount of CMC-Fe complex and the efficiency of removing free iron ions after treating. Sorption testing results showed a strong linear correlation between the phosphorous uptake capacities and the iron contents of the samples adjusted for losses of iron during testing. As anticipated, pretreating with the anionic polymer provided additional sites to complex iron and thereby imparted a greater phosphorous uptake capacity. Although the larger wood particles provided a greater amount of iron for phosphate removal, smaller wood particles may be preferred since they afforded the lowest release of iron relative to the amount of phosphate removed.


Assuntos
Carboximetilcelulose Sódica/metabolismo , Compostos Ferrosos/metabolismo , Tamanho da Partícula , Fosfatos/isolamento & purificação , Polímeros/metabolismo , Madeira/metabolismo , Adsorção , Fósforo/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier
12.
Environ Sci Technol ; 41(9): 3322-8, 2007 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-17539544

RESUMO

Two reactive media [zerovalent iron (ZVI, Fisher Fe0) and amorphous hydrous ferric oxide (HFO)-incorporated porous, naturally occurring aluminum silicate diatomite [designated as Fe (25%)-diatomite]], were tested for batch kinetic, pH-controlled differential column batch reactors (DCBRs), in small- and large-scale column tests (about 50 and 900 mL of bed volume) with groundwater from a hazardous waste site containing high concentrations of arsenic (both organic and inorganic species), as well as other toxic or carcinogenic volatile and semivolatile organic compounds (VOC/SVOCs). Granular activated carbon (GAC) was also included as a reactive media since a permeable reactive barrier (PRB) at the subject site would need to address the hazardous VOC/SVOC contamination as well as arsenic. The groundwater contained an extremely high arsenic concentration (341 mg L(-1)) and the results of ion chromatography and inductively coupled plasma mass spectrometry (IC-ICP-MS) analysis showed that the dominant arsenic species were arsenite (45.1%) and monomethyl arsenic acid (MMAA, 22.7%), while dimethyl arsenic acid (DMAA) and arsenate were only 2.4 and 1.3%, respectively. Based on these proportions of arsenic species and the initial As-to-Fe molar ratio (0.15 molAs mole(-1)), batch kinetic tests revealed that the sorption density (0.076 molAs molFe(-1)) for Fe (25%)-diatomite seems to be less than the expected value (0.086 molAs molFe(-1) calculated from the sorption density data reported by Lafferty and Loeppert (Environ. Sci. Technol. 2005, 39, 2120-2127), implying that natural organic matters (NOMs) might play a significant role in reducing arsenic removal efficiency. The results of pH-controlled DCBR tests using different synthetic species of arsenic solution showed that the humic acid inhibited the MMAA removal of Fe (25%)-diatomite more than arsenite. The mixed system of GAC and Fe (25%)-diatomite increased the arsenic sorption speed to more than that of either individual media alone. This increase might be deduced by the fact that the addition of GAC could enhance arsenic removal performance of Fe (25%)-diatomite through removing comparably high portions of NOMs. Small- and large-scale column studies demonstrated that the empty bed contact time (EBCT) significantly affected sorpton capacities at breakthrough (C = 0.5 C0) forthe Fe0/sand (50/50, w/w) mixture, but notfor GAC preloaded Fe (25%)-diatomite. In the large-scale column tests with actual groundwater conditions, the GAC preloaded Fe (25%)-diatomite effectively reduced arsenic to below 50 microg L(-1) for 44 days; additionally, most species of VOC/SVOCs were also simultaneously attenuated to levels below detection.


Assuntos
Arsênio/isolamento & purificação , Terra de Diatomáceas/química , Poluentes Químicos da Água/isolamento & purificação , Adsorção , Arsênio/química , Carbono/química , Substâncias Húmicas , Ferro/química , Poluentes Químicos da Água/química , Purificação da Água/métodos , Abastecimento de Água
13.
Environ Sci Technol ; 40(5): 1636-43, 2006 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-16568781

RESUMO

In this study, a simplified and effective method was tried to immobilize iron oxide onto a naturally occurring porous diatomite. Experimental resultsfor several physicochemical properties and arsenic edges revealed that iron oxide incorporated into diatomite was amorphous hydrous ferric oxide (HFO). Sorption trends of Fe (25%)-diatomite for both arsenite and arsenate were similar to those of HFO, reported by Dixit and Hering (Environ. Sci. Technol. 2003, 37, 4182-4189). The pH at which arsenite and arsenate are equally sorbed was 7.5, which corresponds to the value reported for HFO. Judging from the number of moles of iron incorporated into diatomite, the arsenic sorption capacities of Fe (25%)-diatomite were comparable to or higher than those of the reference HFO. Furthermore, the surface complexation modeling showed that the constants of [triple bond]SHAsO4- or [triple bond]SAsO4(2-) species for Fe (25%)-diatomite were larger than those reference values for HFO or goethite. Larger differences in constants of arsenate surface species might be attributed to aluminum hydroxyl ([triple bond]Al-OH) groups that can work better for arsenate removal. The pH-controlled differential column batch reactor (DCBR) and small-scale column tests demonstrated that Fe (25%)-diatomite had high sorption speeds and high sorption capacities compared to those of a conventional sorbent (AAFS-50) that is known to be the first preference for arsenic removal performance in Bangladesh. These results could be explained by the fact that Fe (25%)-diatomite contained well-dispersed HFO having a great affinity for arsenic species and well-developed macropores as shown by scanning electron microscopy (SEM) and pore size distribution (PSD) analyses.


Assuntos
Arseniatos/isolamento & purificação , Arsenitos/isolamento & purificação , Compostos Férricos/química , Concentração de Íons de Hidrogênio , Cinética , Microscopia Eletrônica de Varredura , Nitrogênio/química , Difração de Raios X
14.
Bioresour Technol ; 97(18): 2371-6, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16361096

RESUMO

Biomass-based filtration media are of interest as an economical means to remove pollutants and nutrients found in stormwater runoff. Refined aspen wood fiber samples treated with iron salt solutions demonstrated limited capacities to remove (ortho)phosphate from test solutions. To provide additional sites for iron complex formation, and thereby impart a greater capacity for phosphate removal, a fiber pretreatment with an aqueous solution of a non-toxic anionic polymer, carboxymethyl cellulose (CMC), was evaluated. Problems with excessive viscosities during the screening of commercially available CMC products led to the selection of an ultra low viscosity CMC product that was still usable at a 4% concentration in water. Soxhlet extractions of chipped aspen wood and refined aspen wood fiber samples showed a higher extractives content for the refined material. Analysis of these extracts by FTIR spectroscopy suggested that the higher extractives content for the refined material resulted from the fragmentation of cell wall polymers (e.g., lignin, hemicelluloses) normally insoluble in their native states. Spectroscopic analysis of CMC and ferrous chloride treated fibers showed that the complex formed was sufficiently stable to resist removal during subsequent water washes. Equilibrium sorption data, which fit better with a Freundlich isotherm model than a Langmuir isotherm model, showed that phosphate removal could be enhanced by the CMC pretreatment. Results suggest that the process outlined may provide a facile means to improve the phosphate removal capacity of biomass-based stormwater filtration media.


Assuntos
Fosfatos/farmacocinética , Populus/química , Poluentes Químicos da Água/farmacocinética , Adsorção , Carboximetilcelulose Sódica , Compostos Ferrosos , Filtração/métodos , Temperatura , Madeira
15.
Environ Sci Technol ; 38(3): 912-7, 2004 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-14968882

RESUMO

Phosphorus from excess fertilizers and detergents ends up washing into lakes, creeks, and rivers. This overabundance of phosphorus causes excessive aquatic plant and algae growth and depletes the dissolved oxygen supply in the water. In this study, aluminum-impregnated mesoporous adsorbents were tested for their ability to remove phosphate from water. The surface structure of the materials was investigated with X-ray diffraction (XRD), a N2 adsorption-desorption technique, Fourier transform-infrared (FT-IR), and X-ray photoelectron spectroscopy (XPS) to understand the effect of surface properties on the adsorption behavior of phosphate. The mesoporous materials were loaded with Al components by reaction with surface silanol groups. In the adsorption test, the Al-impregnated mesoporous materials showed fast adsorption kinetics as well as high adsorption capacities, compared with activated alumina. The uniform mesopores of the Al-impregnated mesoporous materials caused the diffusion rate in the adsorption process to increase, which in turn caused the fast adsorption kinetics. High phosphate adsorption capacities of the Al-impregnated mesoporous materials were attributed to not only the increase of surface hydroxyl density on Al oxide due to well-dispersed impregnation of Al components but also the decrease in stoichiometry of surface hydroxyl ions to phosphate by the formation of monodentate surface complexes.


Assuntos
Fosfatos/química , Fosfatos/isolamento & purificação , Purificação da Água/métodos , Adsorção , Alumínio/química , Fertilizantes , Cinética , Teste de Materiais , Porosidade , Silicatos/química
16.
J Immunol ; 170(12): 5886-91, 2003 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-12794114

RESUMO

Day 3 thymectomy (D3Tx) leads to a paucity of CD4(+)CD25(+) suppressor T cells, a loss of peripheral tolerance, and the development of organ-specific autoimmune disease in adult mice. Importantly, D3Tx does not lead to autoimmune disease in all mouse strains, indicating that this process is genetically controlled. Previously, we reported linkage of D3Tx-induced autoimmune ovarian dysgenesis (AOD) and its intermediate phenotypes, antiovarian autoantibody responsiveness, oophoritis, and atrophy, to five quantitative trait loci (QTL), designated Aod1 through Aod5. We also showed interaction between these QTL and H2 as well as Gasa2, a QTL controlling susceptibility to D3Tx-induced autoimmune gastritis. To physically map Aod1, interval-specific bidirectional recombinant congenic strains of mice were generated and studied for susceptibility to D3Tx-induced AOD. Congenic mapping studies revealed that Aod1 controls susceptibility to oophoritis and comprises two linked QTL with opposing allelic effects. Aod1a resides between D16Mit211 (23.3 cM) and D16Mit51 (66.75 cM) on chromosome 16. Aod1b maps proximal of Aod1a between D16Mit89 (20.9 cM) and D16Mit211 (23.3 cM) and includes the candidate genes stefin A1, A2, and A3 (Stfa1-Stfa3), inhibitors of cathepsin S, a cysteine protease required for autoantigen presentation, and the development of autoimmune disease of the salivary and lacrimal glands following D3Tx. cDNA sequencing revealed the existence of structural polymorphisms for both Stfa1 and Stfa2. Given the roles of cathepsins in Ag processing and presentation, Stfa1 and Stfa2 alleles have the potential to control susceptibility to autoimmune disease at the level of both CD4(+)CD25(+) suppressor and CD4(+)CD25(-) effector T cells.


Assuntos
Alelos , Doenças Autoimunes/genética , Doenças Autoimunes/imunologia , Predisposição Genética para Doença , Ooforite/genética , Ooforite/imunologia , Locos de Características Quantitativas/imunologia , Timectomia , Sequência de Aminoácidos , Animais , Animais Recém-Nascidos , Apresentação de Antígeno/genética , Autoantígenos/imunologia , Autoantígenos/metabolismo , Catepsinas/antagonistas & inibidores , Catepsinas/fisiologia , Cistatina A , Cistatinas/genética , Cistatinas/isolamento & purificação , Inibidores de Cisteína Proteinase/genética , Inibidores de Cisteína Proteinase/isolamento & purificação , Feminino , Ligação Genética/imunologia , Masculino , Camundongos , Camundongos Congênicos , Camundongos Endogâmicos A , Camundongos Endogâmicos C57BL , Dados de Sequência Molecular , Mapeamento Físico do Cromossomo
17.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-164727

RESUMO

The radial artery as a graft for myocardial revascularization was introduced by Carpentier et al. in the early 1970s. Mid-term results were unfortunately discouraging, and the clinical experience with this graft was interrupted. At the end of the 1980s, these authors reproposed the same arterial conduit with more satisfying results, because of improved technique and pharmacological management of the graft. Between October 1994 and July 1995, 36 patients underwent myocardial revascularization with a radial artery graft in Sejong General Hospital. Left internal mammary artery was concomitantly used as a pedicled graft in 34 patients. Fifteen patients(42%) had a complete arterial graft revascularization. A total of 123 distal anastomoses were performed(average 3.4 per patient), including 36 left internal mammary artery grafts(two sequential in 2 patients), and 23 saphenous vein grafts. The remaining 64 distal anastomoses were performed with radial artery grafts (mean 1.8 per patient). The radial arteries were anastomosed to the circumflex(n=38), diagonal( n=18), right coronary(n=6), and left anterior descending coronary artery(n=2). The percentage of radial artery graft anastomoses(64) to the total anastomoses(123) was 52%. The radial artery was used as a single graft in 10 patients, as a sequential graft in 25 patients, and two grafts in 1 patient. Twenty patients underwent associated procedures : coronary endarterectomy(14), coronary artery patch angioplasty(4), mitral valve repair(1), and repair of ventricular septal rupture(1). One patient died of low cardiac output syndrome and the others had no perioperative myocardial infarction. There are no ischemic and functional complications in the arm or hand after removal of the radial artery. Only 1 patient required reexploration of the arm, for the hematoma evacuation, and 2 patients complained transient thumb dysesthesia of the side of the havested arm. This dysesthesia improved within one month. Postoperative angiographic controls were obtained in 11 patients(31%) postoperative 79 to 210 days(mean 126 days). The patency rate were as follows : left internal mammary artery(100%), saphenous vein(100%), and radial artery(95%). We concluded that the radial artery is useful alternative graft, but long term clinical and angiographic studies are required to dertermine whether wider application is warranted.


Assuntos
Humanos , Braço , Baixo Débito Cardíaco , Ponte de Artéria Coronária , Vasos Coronários , Mãos , Hematoma , Hospitais Gerais , Artéria Torácica Interna , Valva Mitral , Infarto do Miocárdio , Revascularização Miocárdica , Parestesia , Artéria Radial , Veia Safena , Polegar , Transplantes
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