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1.
Aging Ment Health ; 27(12): 2446-2456, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36995263

RESUMEN

OBJECTIVES: Severe weather events have mental health consequences for survivors that may change over time. We assessed post-flood mental health longitudinally in three groups of mostly middle-aged and older adults who varied in current and prior severe weather experiences. METHOD: Predictors of central interest were age, perceived social support, state hope (including agency and pathways), recovery stressors, and prior lifetime trauma. Criterion variables included symptoms of depression, post-traumatic stress disorder (PTSD), and worry. RESULTS: Analyses of variance yielded significant Disaster Exposure Group x Wave interactions for depression and PTSD symptoms. Those with flooded homes and properties had elevated symptoms at Wave 1 which were reduced at Wave 2. Older age was associated with fewer symptoms of depression, PTSD, and worry. Recovery stressors and lifetime trauma predicted more PTSD symptoms. Greater agency predicted less PTSD and depression symptoms, whereas pathways predicted less worry. CONCLUSION: These data show that mental health symptoms may decrease over time for those directly impacted by severe flooding. State hope appears to contribute to better mental health after exposure to a devastating flood. Implications for understanding the dynamic relationships among risk variables and positive factors that promote post-disaster mental health in the years after a flood are considered.

2.
PLoS Pathog ; 17(5): e1009575, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33961680

RESUMEN

HIV-infected infants are at an increased risk of progressing rapidly to AIDS in the first weeks of life. Here, we evaluated immunological and virological parameters in 25 SIV-infected infant rhesus macaques to understand the factors influencing a rapid disease outcome. Infant macaques were infected with SIVmac251 and monitored for 10 to 17 weeks post-infection. SIV-infected infants were divided into either typical (TypP) or rapid (RP) progressor groups based on levels of plasma anti-SIV antibody and viral load, with RP infants having low SIV-specific antibodies and high viral loads. Following SIV infection, 11 out of 25 infant macaques exhibited an RP phenotype. Interestingly, TypP had lower levels of total CD4 T cells, similar reductions in CD4/CD8 ratios and elevated activation of CD8 T cells, as measured by the levels of HLA-DR, compared to RP. Differences between the two groups were identified in other immune cell populations, including a failure to expand activated memory (CD21-CD27+) B cells in peripheral blood in RP infant macaques, as well as reduced levels of germinal center (GC) B cells and T follicular helper (Tfh) cells in spleens (4- and 10-weeks post-SIV). Reduced B cell proliferation in splenic germinal GCs was associated with increased SIV+ cell density and follicular type 1 interferon (IFN)-induced immune activation. Further analyses determined that at 2-weeks post SIV infection TypP infants exhibited elevated levels of the GC-inducing chemokine CXCL13 in plasma, as well as significantly lower levels of viral envelope diversity compared to RP infants. Our findings provide evidence that early viral and immunologic events following SIV infection contributes to impairment of B cells, Tfh cells and germinal center formation, ultimately impeding the development of SIV-specific antibody responses in rapidly progressing infant macaques.


Asunto(s)
Progresión de la Enfermedad , Inmunidad Humoral , Síndrome de Inmunodeficiencia Adquirida del Simio/inmunología , Virus de la Inmunodeficiencia de los Simios/inmunología , Animales , Linfocitos B/inmunología , Linfocitos B/virología , Variación Genética , Centro Germinal/inmunología , Centro Germinal/virología , Humanos , Interferón Tipo I/inmunología , Tejido Linfoide/inmunología , Tejido Linfoide/virología , Macaca mulatta , Fenotipo , Síndrome de Inmunodeficiencia Adquirida del Simio/patología , Síndrome de Inmunodeficiencia Adquirida del Simio/virología , Virus de la Inmunodeficiencia de los Simios/genética , Carga Viral
3.
Arch Pathol Lab Med ; 143(2): 197-205, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30168727

RESUMEN

CONTEXT.­: Duchenne muscular dystrophy is a rare, progressive, and fatal neuromuscular disease caused by dystrophin protein loss. Common investigational treatment approaches aim at increasing dystrophin expression in diseased muscle. Some clinical trials include assessments of novel dystrophin production as a surrogate biomarker of efficacy, which may predict a clinical benefit from treatment. OBJECTIVES.­: To establish an immunofluorescent scanning and digital image analysis workflow that provides an objective approach for staining intensity assessment of the immunofluorescence dystrophin labeling and determination of the percentage of biomarker-positive fibers in muscle cryosections. DESIGN.­: Optimal and repeatable digital image capture was achieved by a rigorously qualified fluorescent scanning process. After scanning qualification, the MuscleMap (Flagship Biosciences, Westminster, Colorado) algorithm was validated by comparing high-power microscopic field total and dystrophin-positive fiber counts obtained by trained pathologists to data derived by MuscleMap. Next, the algorithm was tested on whole-slide images of immunofluorescent-labeled muscle sections from Duchenne muscular dystrophy, Becker muscular dystrophy, and control patients. RESULTS.­: When used under the guidance of a trained pathologist, the digital image analysis tool met predefined validation criteria and demonstrated functional and statistical equivalence with manual assessment. This work is the first, to our knowledge, to qualify and validate immunofluorescent scanning and digital tissue image-analysis workflow, respectively, with the rigor required to support the clinical trial environments. CONCLUSIONS.­: MuscleMap enables analysis of all fibers within an entire muscle biopsy section and provides data on a fiber-by-fiber basis. This will allow future clinical trials to objectively investigate myofibers' dystrophin expression at a greater level of consistency and detail.


Asunto(s)
Distrofina/análisis , Interpretación de Imagen Asistida por Computador/métodos , Distrofia Muscular de Duchenne/diagnóstico , Adolescente , Biopsia , Niño , Preescolar , Femenino , Secciones por Congelación , Humanos , Masculino , Persona de Mediana Edad , Músculo Esquelético/patología
4.
Am J Transplant ; 15(12): 3224-8, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26228743

RESUMEN

We report the first case of enterovirus-D68 infection in an adult living-donor kidney transplant recipient who developed rapidly progressive bulbar weakness and acute flaccid limb paralysis following an upper respiratory infection. We present a 45-year-old gentleman who underwent pre-emptive living-donor kidney transplantation for IgA nephropathy. Eight weeks following transplantation, he developed an acute respiratory illness from enterovirus/rhinovirus that was detectable in nasopharyngeal (NP) swabs. Within 24 h of onset of respiratory symptoms, the patient developed binocular diplopia which rapidly progressed to multiple cranial nerve dysfunctions (acute bulbar syndrome) over the next 24 h. Within the next 48 h, asymmetric flaccid paralysis of the left arm and urinary retention developed. While his neurological symptoms were evolving, the Centers for Disease Control reported that the enterovirus strain from the NP swabs was, in fact, Enterovirus-D68 (EV-D68). Magnetic resonance imaging of the brain demonstrated unique gray matter and anterior horn cell changes in the midbrain and spinal cord, respectively. Constellation of these neurological symptoms and signs was suggestive for postinfectious encephalomyelitis (acute disseminated encephalomyelitis [ADEM]) from EV-D68. Treatment based on the principles of ADEM included intensive physical therapy and other supportive measures, which resulted in a steady albeit slow improvement in his left arm and bulbar weakness, while maintaining stable allograft function.


Asunto(s)
Encefalopatías/etiología , Enterovirus Humano D/patogenicidad , Infecciones por Enterovirus/virología , Fallo Renal Crónico/cirugía , Trasplante de Riñón/efectos adversos , Paraplejía/etiología , Complicaciones Posoperatorias , Enfermedad Aguda , Adulto , Infecciones por Enterovirus/complicaciones , Rechazo de Injerto , Supervivencia de Injerto , Humanos , Fallo Renal Crónico/virología , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Neuroimagen , Pronóstico , Factores de Riesgo , Receptores de Trasplantes
5.
J Microsc ; 255(1): 30-41, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24832212

RESUMEN

Using the optical methods described, specimens can be observed with modified multimodal light microscopes based on interference contrast combined with phase contrast, dark- or bright-field illumination. Thus, the particular visual information associated with interference and phase contrast, dark- and bright-field illumination is joined in real-time composite images appearing in enhanced clarity and purified from typical artefacts, which are apparent in standard phase contrast and dark-field illumination. In particular, haloing and shade-off are absent or significantly reduced as well as marginal blooming and scattering. The background brightness and thus the range of contrast can be continuously modulated and variable transitions can be achieved between interference contrast and complementary illumination techniques. The methods reported should be of general interest for all disciplines using phase and interference contrast microscopy, especially in biology and medicine, and also in material sciences when implemented in vertical illuminators.


Asunto(s)
Microscopía de Contraste de Fase/métodos , Microscopía de Polarización/métodos , Medios de Contraste/química , Oscuridad , Luz
6.
Inorg Chem ; 52(5): 2277-9, 2013 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-23394479

RESUMEN

Heme proteins are exquisitely tuned to carry out diverse biological functions while employing identical heme cofactors. Although heme protein properties are often altered through modification of the protein scaffold, protein function can be greatly expanded and diversified through replacement of the native heme with an unnatural porphyrin of interest. Thus, porphyrin substitution in proteins affords new opportunities to rationally tailor heme protein chemical properties for new biological applications. Here, a highly thermally stable Heme Nitric oxide/OXygen binding (H-NOX) protein is evaluated as a magnetic resonance imaging (MRI) contrast agent. T1 and T2 relaxivities measured for the H-NOX protein containing its native heme are compared to the protein substituted with unnatural manganese(II/III) and gadolinium(III) porphyrins. H-NOX proteins are found to provide unique porphyrin coordination environments and have enhanced relaxivities compared to commercial small-molecule agents. Porphyrin substitution is a promising strategy to encapsulate MRI-active metals in heme protein scaffolds for future imaging applications.


Asunto(s)
Medios de Contraste/química , Hemoproteínas/química , Imagen por Resonancia Magnética , Óxido Nítrico/química , Oxígeno/química , Porfirinas/química , Cristalografía por Rayos X , Modelos Moleculares
7.
Macromolecules ; 45(22): 8982-8990, 2012 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-23226878

RESUMEN

Advances in clinical diagnostic instrumentation have enabled some imaging modalities to be run concurrently. For diagnostic purposes, multimodal imaging can allow for rapid location and accurate identification of a patient's illness. The paramagnetic and near Infra-red (NIR) properties of Dy(III) and Yb(III) are interesting candidates for the development of bimodal NIR and magnetic resonance imaging (MRI) contrast agents. To enhance their intrinsic bimodal properties, these lanthanides were chelated using the hexadentate-all-oxygen-donor-ligand TREN-bis-(1-Me)-3,2-HOPO-TAM-NX (NX, where X = 1, 2 or 3) and subsequently conjugated to the esteramide dendrimer (EA), to improve bioavailability, solubility, and relaxivity. Of these new complexes synthesized and evaluated, DyN1-EA had the largest ionic T(1) relaxivity, 7.60 mM(-1) s(-1), while YbN3-EA had the largest ionic T(2) relaxivity with a NIR quantum yield of 0.17 % when evaluated in mouse serum. This is the first Yb(III) bimodal NIR/T(2) MRI contrast agent of its kind evaluated.

8.
Adv Healthc Mater ; 1(4): 437-42, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23184774

RESUMEN

Configuring RE(2) O(3) nanocrystals with pseudo-2D morphologies confers substantive gains in relaxivities over equivalent spherical counterparts. The most promising arises from Gd(2) O(3) whose ionic transverse and longitudinal relaxivities were as high as r(1) = 12.7 mM(-1) s(-1) and r(2) = 17.2 mM(-1) s(-1) (dispersed in H(2) O, T = 37 °C & B(0) = 1.41 T), pointing to new opportunities to achieve high contrast MRI while concomitantly affording longer half-life potential in vivo.


Asunto(s)
Aumento de la Imagen/métodos , Imagen por Resonancia Magnética/métodos , Nanopartículas , Renio , Medios de Contraste/química , Nanopartículas/ultraestructura , Tamaño de la Partícula , Renio/química
9.
J Microsc ; 247(3): 259-68, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22906013

RESUMEN

Axial phase-darkfield-contrast (APDC) has been developed as an illumination technique in light microscopy which promises significant improvements and a higher variability in imaging of several transparent 'problem specimens'. With this method, a phase contrast image is optically superimposed on an axial darkfield image so that a partial image based on the principal zeroth order maximum (phase contrast) interferes with an image, which is based on the secondary maxima (axial darkfield). The background brightness and character of the resulting image can be continuously modulated from a phase contrast-dominated to a darkfield-dominated character. In order to achieve this illumination mode, normal objectives for phase contrast have to be fitted with an additional central light stopper needed for axial (central) darkfield illumination. In corresponding condenser light masks, a small perforation has to be added in the centre of the phase contrast providing light annulus. These light modulating elements are properly aligned when the central perforation is congruent with the objective's light stop and the light annulus is conjugate with the phase ring. The breadth of the condenser light annulus and thus the intensity of the phase contrast partial image can be regulated with the aperture diaphragm. Additional contrast effects can be achieved when both illuminating light components are filtered at different colours. In this technique, the axial resolution (depth of field) is significantly enhanced and the specimen's three-dimensional appearance is accentuated with improved clarity as well as fine details at the given resolution limit. Typical artefacts associated with phase contrast and darkfield illumination are reduced in our methods.


Asunto(s)
Simulación por Computador , Aumento de la Imagen/métodos , Imagenología Tridimensional/métodos , Microscopía de Contraste de Fase/métodos , Animales , Diatomeas/citología , Peces/anatomía & histología , Luz , Microscopía de Contraste de Fase/normas , Poliquetos/anatomía & histología , Piel/anatomía & histología
10.
J Am Chem Soc ; 134(19): 8046-9, 2012 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-22545921

RESUMEN

Particle-based magnetic resonance imaging (MRI) contrast agents have been the focus of recent studies, primarily due to the possibility of preparing multimodal particles capable of simultaneously targeting, imaging, and treating specific biological tissues in vivo. In addition, particle-based MRI contrast agents often have greater sensitivity than commercially available, soluble agents due to decreased molecular tumbling rates following surface immobilization, leading to increased relaxivities. Mesoporous silica particles are particularly attractive substrates due to their large internal surface areas. In this study, we immobilized a unique phosphonate-containing ligand onto mesoporous silica particles with a range of pore diameters, pore volumes, and surface areas, and Gd(III) ions were then chelated to the particles. Per-Gd(III) ionic relaxivities ranged from ∼2 to 10 mM(-1) s(-1) (37 °C, 60 MHz), compared to 3.0-3.5 mM(-1) s(-1) for commercial agents. The large surface areas allowed many Gd(III) ions to be chelated, leading to per-particle relaxivities of 3.3 × 10(7) mM(-1) s(-1), which is the largest value measured for a biologically suitable particle.


Asunto(s)
Medios de Contraste/química , Gadolinio/química , Imagen por Resonancia Magnética , Microesferas , Organofosfonatos/química , Dióxido de Silicio/química , Porosidad
11.
Contrast Media Mol Imaging ; 7(1): 95-9, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22344885

RESUMEN

Commercial gadolinium magnetic resonance imaging (MRI) contrast agents are limited by low relaxivity (r1) and coordination to only a single water molecule (q = 1). Consequently, gram quantities of these agents must be injected to obtain sufficient diagnostic contrast. In this study, MRI contrast agents for T(1) and T2 relaxivity were synthesized using hydroxypyridinone and terephthalamide chelators with mesityl and 1,4,7-triazacyclononane capping moieties. When covalently conjugated to a highly biocompatible esteramide dendrimer, T2 relaxation rates up to 52 mm(-1) s(-1) and T1 relaxation rates up to 31 mm(-1) s(-1) per gadolinium were observed under clinically relevant conditions. These values are believed to be brought about by using a dendritic macromolecule to decrease the molecular tumbling time of the small molecule complexes. These agents also show high aqueous solubility and low toxicity in vitro. In this study we report six new compounds: three discrete complexes and three dendrimer conjugates.


Asunto(s)
Medios de Contraste/síntesis química , Dendrímeros/síntesis química , Gadolinio/química , Compuestos Heterocíclicos/química , Imagen por Resonancia Magnética/métodos , Piridonas/química , Medios de Contraste/química , Medios de Contraste/toxicidad , Complejos de Coordinación/síntesis química , Complejos de Coordinación/química , Complejos de Coordinación/toxicidad , Dendrímeros/química , Dendrímeros/toxicidad , Células HeLa/efectos de los fármacos , Humanos , Estructura Molecular , Protones , Solubilidad , Agua
12.
Lett Appl Microbiol ; 54(3): 263-6, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22176341

RESUMEN

AIMS: To test the feasibility of identifying Staphylococcus aureus with a fluorescence in situ hybridization (FISH) assay that uses a single hot-plate and urea-NaCl reagents. METHODS AND RESULTS: Slides spotted with S. aureus and treated with methanol and lysozyme were incubated with urea-NaCl reagents on a hot-plate with a precise temperature control and identified with specific DNA probes. CONCLUSIONS: Staphylococcus aureus was detected and differentiated from Staphylococcus epidermidis in 1 h with a novel FISH method that used a single hot-plate and in the absence of dimethyl formamide. SIGNIFICANCE AND IMPACT OF STUDY: A rapid hot-plate FISH assay with urea-NaCl and without toxic dimethyl formamide might be useful if FISH is run infrequently or where resources are limited.


Asunto(s)
Hibridación Fluorescente in Situ/métodos , Cloruro de Sodio/química , Staphylococcus aureus/aislamiento & purificación , Urea/química , Sondas de ADN , Dimetilformamida , Metanol , Muramidasa , Especificidad de la Especie , Staphylococcus aureus/genética
13.
Med Phys ; 39(6Part7): 3677, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28519780

RESUMEN

PURPOSE: Previous studies have shown atlas-based segmentation using a single best matched (SBM) atlas subject can significantly reduce contouring time. A new multi-atlas approach has been shown to provide greater accuracy than SBM for cancer of the head and neck. The goal of this study was to evaluate the multi-atlas technique for lung cancer treatment planning. METHODS: An institution's SBRT lung atlas containing 82 subjects was utilized for atlas segmentation. Each atlas subject contained manually defined contours of the esophagus, cord, heart, left lung, right lung, and trachea. CT scans and contours for 16 subjects were evaluated. SBM used the one automatically determined best match for segmentation. Multi-atlas used multiple automatically determined best matches: 3, 4, and 5, respectively. The final segmentation for multi-atlas was generated using Majority Vote which comprises the area of overlap for at least half of the individual segmentations (2 of 3, 2 of 4, and 3 of 5, respectively). Average Dice Similarity Coefficients (DSC) were calculated for each structure to compare against manually defined 'gold' standard contours for that subject. Overall percent improvement was calculated as the proportion of the error corrected by the method, or % difference on 1-DSC. RESULTS: All multi-atlas methods were significantly more accurate than SBM (p-value < 0.0005) with average DSC of 0.802 +/- 0.172, 0.809 +/ 0.163, 0.802 +/- 0.182 respectively for Multi-3, Multi-4, and Multi-5 compared to 0.773 +/- 0.187 for SBM. No significant differences existed between the different multi-atlas approaches. Overall, Multi-4 showed the greatest improvement over SBM with 16% improvement followed by Multi-3 and Multi-5 at 12%. CONCLUSIONS: Each multi-atlas approach resulted in significantly more accurate contours compared to the SBM. While still requiring some editing, this method for segmentation using multiple atlases shows promise for further decreasing the contouring time required for lung cancer. MIM Software Inc.

14.
Eur J Inorg Chem ; 2012(12): 2108-2114, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23539072

RESUMEN

Magnetic resonance imaging (MRI) contrast agents represent a worldwide billion-dollar market annually. While T1 relaxivity enhancement contrast agents receive greater attention and a significantly larger market share, the commercial potential for T2 relaxivity enhancing contrast agents remains a viable diagnostic option due to their increased relaxivity at high field strengths. Improving the contrast and biocompatibility of T2 MRI probes may enable new diagnostic prospects for MRI. Paramagnetic lanthanides have the potential to decrease T1 and T2 proton relaxation times, but are not commercially used in MRI diagnostics as T2 agents. In this article, oxygen donor chelates (hydroxypyridinone, HOPO, and terephthalamide, TAM) of various lanthanides are demonstrated as biocompatible macromolecular dendrimer conjugates for the development of T2 MRI probes. These conjugates have relaxivities up to 374 mm-1s-1 per dendrimer, high bioavailability, and low in vitro toxicity.

15.
J Am Chem Soc ; 133(8): 2390-3, 2011 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-21294571

RESUMEN

One essential requirement for more sensitive gadolinium-based MRI contrast agents is to slow the molecular tumbling of the gadolinium(III) ion, which increases the gadolinium's relaxivity (i.e., its ability to speed up the NMR relaxation of nearby water molecules). One route to this is through conjugation to high-molecular-weight polymers such as dendrimers. In this work, amine-functionalized TREN-bis(1,2-HOPO)-TAM-ethylamine and TREN-bis(1-Me-3,2-HOPO)-TAM-ethylamine ligands have been synthesized and attached to biocompatible 40 kDa esteramide (EA)- and poly-l-lysine (PLL)-based dendrimers capable of binding up to eight gadolinium complexes. These conjugates have T(1) relaxivities of up to 38.14 ± 0.02 mM(-1) s(-1) per gadolinium at 37 °C, corresponding to relaxivities of up to 228 mM(-1) s(-1) per dendrimer molecule. This relaxivity expressed on a "per Gd" basis is several times that of the small-molecule complexes and an order of magnitude higher than that of current commercial agents. Because of their high performance and low toxicity, these macromolecules may constitute an attractive complement to currently available gadolinium(III)-based contrast agents.


Asunto(s)
Amidas/química , Medios de Contraste/química , Dendrímeros/química , Ésteres/química , Gadolinio/química , Piridonas/química , Medios de Contraste/síntesis química , Dendrímeros/síntesis química , Ligandos , Imagen por Resonancia Magnética , Estructura Molecular , Estereoisomerismo
16.
Insect Mol Biol ; 18(5): 661-72, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19754743

RESUMEN

Transgenic Aedes aegypti were engineered to express a virus-derived, inverted repeat (IR) RNA in the mosquito midgut to trigger RNA interference (RNAi) and generate resistance to dengue virus type 2 (DENV2) in the vector. Here we characterize genotypic and phenotypic stabilities of one line, Carb77, between generations G(9) and G(17). The anti-DENV2 transgene was integrated at a single site within a noncoding region of the mosquito genome. The virus resistance phenotype was strong until G(13) and suppressed replication of different DENV2 genotypes. From G(14)-G(17) the resistance phenotype to DENV2 became weaker and eventually was lost. Although the sequence of the transgene was not mutated, expression of the IR effector RNA was not detected and the Carb77 G(17) mosquitoes lost their ability to silence the DENV2 genome.


Asunto(s)
Antivirales/metabolismo , Culicidae/genética , Culicidae/virología , Virus del Dengue/fisiología , Genes de Insecto , Animales , Animales Modificados Genéticamente , Secuencia de Bases , Femenino , Genotipo , Patrón de Herencia/genética , Datos de Secuencia Molecular , Mutagénesis Insercional/genética , Fenotipo , Factores de Tiempo
17.
Opt Express ; 16(26): 21958-63, 2008 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-19104630

RESUMEN

Efficient multi-Watt continuous-wave (CW) yellow emission at 586.5 nm is demonstrated through intracavity frequency-doubling of a Nd:GdVO(4) self-Raman laser pumped at 880 nm. 2.51 W of CW yellow emission with an overall diode-to-yellow conversion efficiency of 12.2% is achieved through the use of a 20 mm long Nd:GdVO(4) self-Raman crystal and an intracavity mirror which facilitates collection of yellow emission generated within the resonator, and reduces thermal loading of the laser crystal.

18.
Opt Express ; 16(5): 3261-72, 2008 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-18542414

RESUMEN

We report increased wavelength options from Raman lasers for Raman media having two Raman modes of similar gain coefficient. For an external-cavity potassium gadolinium tungstate Raman laser pumped at 532 nm, we show that two sets of Stokes orders are generated simultaneously by appropriate orientation of the Raman crystal, and also wavelengths that correspond to sums of the two Raman modes. Up to 14 visible Stokes lines were observed in the wavelength range 555-675 nm. The increase in Stokes wavelengths also enables a much greater selection of wavelengths to be accessed via intracavity nonlinear sum frequency and difference frequency mixing. For example, we demonstrate 30 output wavelength options for a wavelength-selectable 271-321 nm Raman laser with intracavity sum frequency mixing in BBO. We also present a theoretical analysis that enables prediction of wavelength options for dual Raman mode systems.


Asunto(s)
Diseño Asistido por Computadora , Rayos Láser , Modelos Teóricos , Espectrometría Raman/instrumentación , Simulación por Computador , Diseño de Equipo , Análisis de Falla de Equipo , Rayos Ultravioleta
19.
Arterioscler Thromb Vasc Biol ; 27(8): 1857-63, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17561491

RESUMEN

OBJECTIVE: Oxidative stress contributes to the pathogenesis of many diseases, including atherosclerosis and sepsis. We have previously described a novel class of therapeutic compounds with antioxidant and antiinflammatory properties. However, at present, the intracellular targets of these compounds have not been identified. The purpose of this study was to elucidate the mechanism by which 2 structurally-related antioxidants (AGI-1067 and AGI-1095) inhibit LPS induction of tissue factor (TF) expression in human monocytic cells and endothelial cells. METHODS AND RESULTS: We found that succinobucol (AGI-1067) and AGI-1095 inhibited LPS induction of TF expression in both monocytic cells and endothelial cells. These compounds also reduced LPS induction of nuclear AP-1 and expression of Egr-1 without affecting nuclear translocation of NF-kappaB. Importantly, these antioxidants inhibited LPS activation of the redox-sensitive kinase, apoptosis signal-regulating kinase-1 (ASK1) and the mitogen-activated protein kinases (MAPKs) p38, ERK1/2, and JNK1/2. CONCLUSIONS: AGI-1067 and AGI-1095 inhibit TF gene expression in both monocytic cells and endothelial cells through a mechanism that involves the inhibition of the redox-sensitive MAP3K, ASK1. These compounds selectively reduce the activation/induction of MAPK, AP-1, and Egr-1 without affecting NF-kappaB nuclear translocation.


Asunto(s)
Antioxidantes/farmacología , Lipopolisacáridos/farmacología , MAP Quinasa Quinasa Quinasa 5/farmacología , Proteína Quinasa 1 Activada por Mitógenos/farmacología , Tromboplastina/metabolismo , Northern Blotting , Western Blotting , Comunicación Celular , Células Cultivadas , Células Endoteliales/efectos de los fármacos , Células Endoteliales/fisiología , Activación Enzimática , Regulación de la Expresión Génica , Humanos , Monocitos/efectos de los fármacos , Monocitos/fisiología , Estrés Oxidativo , Probabilidad , ARN Mensajero/análisis , Sensibilidad y Especificidad , Transducción de Señal
20.
Insect Mol Biol ; 16(2): 199-206, 2007 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17298556

RESUMEN

Putative U6snRNA polymerase III (PolIII) promoters were cloned from the Anopheles gambiae and Aedes aegypti genomes. The PolIII promoters were tested for their ability to express short-hairpin RNA (shRNA) targeted to firefly luciferase and to mediate RNA interference (RNAi) knockdown of a co-transfected luciferase reporter gene vector in AG-55 Anopheles gambiae and ATC-10 Aedes aegypti cells. Promoters capable of silencing expression of the co-transfected luciferase plasmid by up to 95% in AG-55 cells and up to 75% in ATC-10 cells were identified. RNase protection experiments allowed detection of the 19 nt luciferase short-interfering RNA (siRNA) in transfected cells. These findings indicate that mosquito U6snRNA gene promoters can be used for production of shRNA to induce the RNAi response in mosquito cells.


Asunto(s)
Aedes/genética , Anopheles/genética , Regiones Promotoras Genéticas , Interferencia de ARN , ARN Nuclear Pequeño/genética , Animales , Secuencia de Bases , Luciferasas de Luciérnaga/genética , Datos de Secuencia Molecular , ARN Polimerasa III/genética , ARN Interferente Pequeño
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