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1.
J Fungi (Basel) ; 10(3)2024 Mar 06.
Article in English | MEDLINE | ID: mdl-38535209

ABSTRACT

Colletotrichum coccodes (Wallr.) Hughes is an asexual fungus with five vegetative compatibility groups. It was postulated that C. coccodes was isolated at the center of origin of potato at one time, and due to the movement of potato around the globe, the fungus was established on each continent but became bottlenecked and genetically unable to form stable heterokaryons via vegetative compatibility grouping (VCG) studies. The objectives of this study were (i) to determine if the VCGs around the world are related to the VCGs in Chile, (ii) to determine the diversity of C. coccodes populations in Chile, and (iii) to find any evidence for a cryptic sexual life cycle for this fungus. Worldwide C. coccodes populations have been found to be genetically correlated and belong to one or more C. coccodes-identified VCGs. The most distributed VCG in Chile was VCG2, which is the most common VCG in North America. We hypothesize that one or more VCGs had spread from Chile to the rest of the world. Precautions and further studies should be investigated by using other molecular markers and gene sequencing.

2.
Blood ; 143(2): 139-151, 2024 Jan 11.
Article in English | MEDLINE | ID: mdl-37616575

ABSTRACT

ABSTRACT: Patients with multiple myeloma (MM) treated with B-cell maturation antigen (BCMA)-specific chimeric antigen receptor (CAR) T cells usually relapse with BCMA+ disease, indicative of CAR T-cell suppression. CD200 is an immune checkpoint that is overexpressed on aberrant plasma cells (aPCs) in MM and is an independent negative prognostic factor for survival. However, CD200 is not present on MM cell lines, a potential limitation of current preclinical models. We engineered MM cell lines to express CD200 at levels equivalent to those found on aPCs in MM and show that these are sufficient to suppress clinical-stage CAR T-cells targeting BCMA or the Tn glycoform of mucin 1 (TnMUC1), costimulated by 4-1BB and CD2, respectively. To prevent CD200-mediated suppression of CAR T cells, we compared CRISPR-Cas9-mediated knockout of the CD200 receptor (CD200RKO), to coexpression of versions of the CD200 receptor that were nonsignaling, that is, dominant negative (CD200RDN), or that leveraged the CD200 signal to provide CD28 costimulation (CD200R-CD28 switch). We found that the CD200R-CD28 switch potently enhanced the polyfunctionality of CAR T cells, and improved cytotoxicity, proliferative capacity, CAR T-cell metabolism, and performance in a chronic antigen exposure assay. CD200RDN provided modest benefits, but surprisingly, the CD200RKO was detrimental to CAR T-cell activity, adversely affecting CAR T-cell metabolism. These patterns held up in murine xenograft models of plasmacytoma, and disseminated bone marrow predominant disease. Our findings underscore the importance of CD200-mediated immune suppression in CAR T-cell therapy of MM, and highlight a promising approach to enhance such therapies by leveraging CD200 expression on aPCs to provide costimulation via a CD200R-CD28 switch.


Subject(s)
Immunotherapy, Adoptive , Multiple Myeloma , Humans , Mice , Animals , Multiple Myeloma/metabolism , CD28 Antigens/metabolism , T-Lymphocytes , B-Cell Maturation Antigen/metabolism , Neoplasm Recurrence, Local/metabolism
3.
PLoS One ; 18(1): e0279877, 2023.
Article in English | MEDLINE | ID: mdl-36662880

ABSTRACT

For centuries, humans occupying arid regions of North America have maintained an intricate relationship with Agave (Agavoideae, Asparagaceae). Today Agave cultivation, primarily for beverage production, provides an economic engine for rural communities throughout Mexico. Among known dryland-farming methods, the use of rock piles and cattle-grazed areas stand out as promising approaches for Agave cultivation. Identifying new cultivation areas to apply these approaches in Arizona, USA and Sonora, Mexico warrants a geographic assessment of areas outside the known ranges of rock piles and grasslands. The objective of this study was to predict areas for dryland-farming of Agave and develop models to identify potential areas for Agave cultivation. We used maximum entropy (MaxEnt) ecological-niche-modeling algorithms to predict suitable areas for Agave dryland farming. The model was parameterized using occurrence records of Hohokam rock piles in Arizona and grassland fields cultivated with Agave in Sonora. Ten environmental-predictor variables were used in the model, downloaded from the WorldClim 2 climate database. The model identified potential locations for using rock piles as dryland-farming methods from south-central Arizona to northwestern Sonora. The Agave-grassland model indicated that regions from central to southern Sonora have the highest potential for cultivation of Agave, particularly for the species Agave angustifolia. Results suggest that there are many suitable areas where rock piles can be used to cultivate Agave in the Sonoran Desert, particularly in the border of southeastern Arizona and northwest Sonora. Likewise, cattle-grazing grasslands provide a viable environment for cultivating Agave in southern Sonora, where the expanding bacanora-beverage industry continues to grow and where different Agave products (e.g., syrups, fructans, saponins, and medicinal compounds) can potentially strengthen local economies.


Subject(s)
Agave , Asparagaceae , Humans , Animals , Cattle , Mexico , Arizona , Agriculture , Desert Climate
4.
Chemosphere ; 274: 129586, 2021 Jul.
Article in English | MEDLINE | ID: mdl-33529957

ABSTRACT

Natural chlorate (ClO3-) is widely distributed in terrestrial and extraterrestrial environments. To improve understanding of the origins and distribution of ClO3-, we developed and tested methods to determine the multi-dimensional isotopic compositions (δ18O, Δ17O, δ37Cl, 36Cl/Cl) of ClO3- and then applied the methods to samples of natural nitrate-rich caliche-type salt deposits in the Atacama Desert, Chile, and Death Valley, USA. Tests with reagents and artificial mixed samples indicate stable-isotope ratios were minimally affected by the purification processes. Chlorate extracted from Atacama samples had δ18O = +7.0 to +11.1‰, Δ17O = +5.7 to +6.4‰, δ37Cl = -1.4 to +1.3‰, and 36Cl/Cl = 48 × 10-15 to 104 × 10-15. Chlorate from Death Valley samples had δ18O = -6.9 to +1.6‰, Δ17O = +0.4 to +2.6‰, δ37Cl = +0.8 to +1.0‰, and 36Cl/Cl = 14 × 10-15 to 44 × 10-15. Positive Δ17O values of natural ClO3- indicate that its production involved reaction with O3, while its Cl isotopic composition is consistent with a tropospheric or near-surface source of Cl. The Δ17O and δ18O values of natural ClO3- are positively correlated, as are those of ClO4- and NO3- from the same localities, possibly indicating variation in the relative contributions of O3 as a source of O in the formation of the oxyanions. Additional isotopic analyses of ClO3- could provide stronger constraints on its production mechanisms and/or post-formational alterations, with applications for environmental forensics, global biogeochemical cycling of Cl, and the origins of oxyanions detected on Mars.


Subject(s)
Chlorates , Nitrates , Chile , Nitrates/analysis
5.
Appl Microbiol Biotechnol ; 103(19): 8035-8049, 2019 Oct.
Article in English | MEDLINE | ID: mdl-31407040

ABSTRACT

Biotechnologies that aim to produce renewable fuels, chemicals, and bioproducts from residual ligno(hemi)cellulosic biomass mostly rely on enzymatic depolymerization of plant cell walls (PCW). This process requires an arsenal of diverse enzymes, including xylanases, which synergistically act on the hemicellulose, reducing the long and complex xylan chains to oligomers and simple sugars. Thus, xylanases play a crucial role in PCW depolymerization. Until recently, the largest xylanase family, glycoside hydrolase family 11 (GH11) has been exclusively represented by endo-catalytic ß-1,4- and ß-1,3-xylanases. Analysis of a metatranscriptome library from a microbial lignocellulose community resulted in the identification of an unusual exo-acting GH11 ß-1,4-xylanase (MetXyn11). Detailed characterization has been performed on recombinant MetXyn11 including determination of its low-resolution small-angle X-ray scattering (SAXS) molecular envelope in solution. Our results reveal that MetXyn11 is a monomeric globular enzyme that liberates xylobiose from heteroxylans as the only product. MetXyn11 has an optimal activity in a pH range from 6 to 9 and an optimal temperature of 50 °C. The enzyme maintained above 65% of its original activity in the pH range 5 to 6 after being incubated for 72 h at 50 °C. Addition of the enzyme to a commercial enzymatic cocktail (CelicCtec3) promoted a significant increase of enzymatic hydrolysis yields of hydrothermally pretreated sugarcane bagasse (16% after 24 h of hydrolysis).


Subject(s)
Endo-1,4-beta Xylanases/chemistry , Endo-1,4-beta Xylanases/metabolism , Microbial Consortia , Disaccharides/metabolism , Endo-1,4-beta Xylanases/isolation & purification , Enzyme Stability , Gene Expression Profiling , Hydrogen-Ion Concentration , Metagenomics , Protein Conformation , Recombinant Proteins/chemistry , Recombinant Proteins/isolation & purification , Recombinant Proteins/metabolism , Scattering, Small Angle , Temperature , Xylans/metabolism
6.
Rev Sci Instrum ; 90(4): 045116, 2019 Apr.
Article in English | MEDLINE | ID: mdl-31043009

ABSTRACT

In this work, we present a commercial CMOS (Complementary Metal Oxide Semiconductor) Raspberry Pi camera implemented as a Near-Infrared detector for both spatial and temporal characterization of femtosecond pulses delivered from a femtosecond Erbium Doped Fiber laser (fs-EDFL) @ 1.55 µm, based on the Two Photon Absorption (TPA) process. The capacity of the device was assessed by measuring the spatial beam profile of the fs-EDFL and comparing the experimental results with the theoretical Fresnel diffraction pattern. We also demonstrate the potential of the CMOS Raspberry Pi camera as a wavefront sensor through its a nonlinear response in a Shack-Hartmann array and for the temporal characterization of the femtosecond pulses delivered from the fs-EDFL through TPA Intensity autocorrelation measurements. The direct pulse detection and measurement, through the nonlinear response with a CMOS, is proposed as a novel and affordable high-resolution and high-sensitivity alternative to costly detectors such as CCDs, wavefront sensors and beam profilers @ 1.55 µm. The measured fluence threshold, down to 17.5 µJ/cm2, and pJ/pulse energy response represents the lowest reported values applied as a beam profiler and a TPA Shack-Hartmann wavefront sensor, to our knowledge.

7.
J Biophotonics ; 11(8): e201700235, 2018 08.
Article in English | MEDLINE | ID: mdl-29498484

ABSTRACT

The gradual process in which the crystalline lens is cloudy due to the appearance of elements giving rise to variations in the refractive index is known as cataract. Clinical assessment is usually complicated because it considers patient's perception, and individuals with similar development have different visual deficits. This work presents a model which considers the fluctuations in the refractive index as spherical particles produce measurable scatter radial profiles patterns on the retina. Measurements for 2 different wavelengths simultaneously provide information on particle size and a quantitative assessment by measurement of the fluctuations of the refractive index.


Subject(s)
Cataract/physiopathology , Eye/physiopathology , Eye/radiation effects , Scattering, Radiation , Humans , Models, Biological , Refractometry , Retina/physiopathology , Retina/radiation effects
8.
Mol Pain ; 13: 1744806917743479, 2017.
Article in English | MEDLINE | ID: mdl-29108465

ABSTRACT

Abstract: Morphine is a well-characterized and effective analgesic commonly used to provide pain relief to patients suffering from both acute and chronic pain conditions. Despite its widespread use and effectiveness, one of the major drawbacks of morphine is its relatively short half-life of approximately 4 h. This short half-life often necessitates multiple administrations of the drug each day, which may contribute to both dependence and tolerance to morphine. Here, we tested the analgesic properties of a new polymer form of morphine known as PolyMorphine. This polymer has monomeric units of morphine incorporated into a poly(anhydride-ester) backbone that has been shown to hydrolyze into free morphine in vitro. Using an animal model of chronic pain, the spared nerve injury surgery, we showed that PolyMorphine is able to block spared nerve injury-induced hypersensitivity in mice for up to 24-h post-administration. Free morphine was shown to only block spared nerve injury-induced hypersensitivity for up to 2-h post-injection. PolyMorphine was also shown to act through the mu opioid receptor due to the ability of naloxone (a mu opioid receptor antagonist) to block PolyMorphine-induced analgesia in spared nerve injury animals pretreated with PolyMorphine. Additionally, we observed that PolyMorphine causes similar locomotor and constipation side effects as free morphine. Finally, we investigated if PolyMorphine had any effects in a non-evoked pain assay, conditioned place preference. Pretreatment of spared nerve injury mice with PolyMorphine blocked the development of conditioned place preference for 2-methyl-6-(phenylethynyl)pyridine (MPEP), a short-lasting mGluR5 antagonist with analgesic-like properties. Free morphine does not block the development of preference for MPEP, suggesting that PolyMorphine has longer lasting analgesic effects compared to free morphine. Together, these data show that PolyMorphine has the potential to provide analgesia for significantly longer than free morphine while likely working through the same receptor.


Subject(s)
Analgesics, Opioid/pharmacology , Morphine/pharmacology , Peripheral Nervous System Diseases/drug therapy , Receptors, Opioid, mu/drug effects , Animals , Drug Tolerance/physiology , Mice, Inbred C57BL , Morphine/chemistry , Naloxone/pharmacology , Narcotic Antagonists/pharmacology
9.
PLoS Negl Trop Dis ; 11(2): e0005137, 2017 02.
Article in English | MEDLINE | ID: mdl-28231240

ABSTRACT

Schistosomiasis affects approximately 240 million people in the world. Schistosoma mansoni eggs in the liver induce periportal fibrosis and hepatic failure driven by monocyte recruitment and macrophage activation, resulting in robust Th2 response. Here, we suggested a possible involvement of Galectin-3 (Gal-3), histone deacetylases (HDACs), and Hedgehog (Hh) signaling with macrophage activation during Th1/Th2 immune responses, fibrogranuloma reaction, and tissue repair during schistosomiasis. Gal-3 is highly expressed by liver macrophages (Kupffer cells) around Schistosoma eggs. HDACs and Hh regulate macrophage polarization and hepatic stellate cell activation during schistosomiasis-associated fibrogenesis. Previously, we demonstrated an abnormal extracellular matrix distribution in the liver that correlated with atypical monocyte-macrophage differentiation in S. mansoni-infected, Gal-3-deficient (Lgals3-/-) mice. New findings explored in this review focus on the chronic phase, when wild-type (Lgals3+/+) and Lgals3-/- mice were analyzed 90 days after cercariae infection. In Lgals3-/- infected mice, there was significant inflammatory infiltration with myeloid cells associated with egg destruction (hematoxylin and eosin staining), phagocytes (specifically Kupffer cells), numerically reduced and diffuse matrix extracellular deposition in fibrotic areas (Gomori trichrome staining), and severe disorganization of collagen fibers surrounding the S. mansoni eggs (reticulin staining). Granuloma-derived stromal cells (GR cells) of Lgals3-/- infected mice expressed lower levels of alpha smooth muscle actin (α-SMA) and eotaxin and higher levels of IL-4 than Lgals3+/+ mice (real-time PCR). The relevant participation of macrophages in these events led us to suggest distinct mechanisms of activation that culminate in defective fibrosis in the liver of Lgals3-/- infected mice. These aspects were discussed in this review, as well as the possible interference between Gal-3, HDACs, and Hh signaling during progressive liver fibrosis in S. mansoni-infected mice. Further studies focused on macrophage roles could elucidate these questions and clear the potential utility of these molecules as antifibrotic targets.


Subject(s)
Galectin 3/metabolism , Hedgehogs/metabolism , Histone Deacetylases/metabolism , Liver Cirrhosis/metabolism , Schistosomiasis/complications , Animals , Galectin 3/genetics , Hedgehogs/genetics , Histone Deacetylases/genetics , Humans , Liver Cirrhosis/etiology , Liver Cirrhosis/genetics , Schistosomiasis/parasitology , Schistosomiasis japonica/parasitology , Signal Transduction
10.
Sci Rep ; 6: 38781, 2016 12 12.
Article in English | MEDLINE | ID: mdl-27941835

ABSTRACT

Microbial communities (MCs) create complex metabolic networks in natural habitats and respond to environmental changes by shifts in the community structure. Although members of MCs are often not amenable for cultivation in pure culture, it is possible to obtain a greater diversity of species in the laboratory setting when microorganisms are grown as mixed cultures. In order to mimic the environmental conditions, an appropriate growth medium must be applied. Here, we examined the hypothesis that a greater diversity of microorganisms can be sustained under nutrient-limited conditions. Using a 16 S rRNA amplicon metagenomic approach, we explored the structure of a compost-derived MC. During a five-week time course the MC grown in minimal medium with sugarcane bagasse (SCB) as a sole carbon source showed greater diversity and enrichment in lignocellulose-degrading microorganisms. In contrast, a MC grown in nutrient rich medium with addition of SCB had a lower microbial diversity and limited number of lignocellulolytic species. Our approach provides evidence that factors such as nutrient availability has a significant selective pressure on the biodiversity of microorganisms in MCs. Consequently, nutrient-limited medium may displace bacterial generalist species, leading to an enriched source for mining novel enzymes for biotechnology applications.


Subject(s)
Biodiversity , Cellulose/metabolism , Composting , Microbial Consortia/physiology , Saccharum/metabolism
11.
Rev Sci Instrum ; 85(4): 043105, 2014 Apr.
Article in English | MEDLINE | ID: mdl-24784591

ABSTRACT

In the present work, we applied an amplitude-spatial light modulator to shape the spectral amplitude of femtosecond pulses in a single step, without an iterative algorithm, by using an inversion method defined as the generalized retardance function. Additionally, we also present a single step method to shape the intensity profile defined as the influence matrix. Numerical and experimental results are presented for both methods.

12.
J Contam Hydrol ; 160: 12-20, 2014 May.
Article in English | MEDLINE | ID: mdl-24594409

ABSTRACT

The Waste Isolation Pilot Plant (WIPP) in New Mexico is the first geologic repository for disposal of transuranic nuclear waste from defense-related programs of the US Department of Energy. It is constructed within halite beds of the Permian-age Salado Formation. The Culebra Dolomite, confined within Rustler Formation evaporites overlying the Salado Formation, is a potential pathway for radionuclide transport from the repository to the accessible environment in the human-disturbed repository scenario. Although extensive subsurface characterization and numerical flow modeling of groundwater has been done in the vicinity of the WIPP, few studies have used natural isotopic tracers to validate the flow models and to better understand solute transport at this site. The advent of Atom-Trap Trace Analysis (ATTA) has enabled routine measurement of cosmogenic (81)Kr (half-life 229,000 yr), a near-ideal tracer for long-term groundwater transport. We measured (81)Kr in saline groundwater sampled from two Culebra Dolomite monitoring wells near the WIPP site, and compared (81)Kr model ages with reverse particle-tracking results of well-calibrated flow models. The (81)Kr model ages are ~130,000 and ~330,000 yr for high-transmissivity and low-transmissivity portions of the formation, respectively. Compared with flow model results which indicate a relatively young mean hydraulic age (~32,000 yr), the (81)Kr model ages imply substantial physical attenuation of conservative solutes in the Culebra Dolomite and provide limits on the effective diffusivity of contaminants into the confining aquitards.


Subject(s)
Groundwater/analysis , Krypton Radioisotopes/analysis , Krypton/analysis , Water Pollutants, Chemical/analysis , Models, Theoretical , New Mexico , Water Movements
13.
Environ Sci Technol ; 44(13): 4869-76, 2010 Jul 01.
Article in English | MEDLINE | ID: mdl-20521813

ABSTRACT

Perchlorate (ClO(4)(-)) has been detected widely in groundwater and soils of the southwestern United States. Much of this ClO(4)(-) appears to be natural, and it may have accumulated largely through wet and dry atmospheric deposition. This study evaluates the isotopic composition of natural ClO(4)(-) indigenous to the southwestern U.S. Stable isotope ratios were measured in ClO(4)(-) (delta(18)O, Delta(17)O, delta(37)Cl) and associated NO(3)(-) (delta(18)O, Delta(17)O, delta(15)N) in groundwater from the southern High Plains (SHP) of Texas and New Mexico and the Middle Rio Grande Basin (MRGB) in New Mexico, from unsaturated subsoil in the SHP, and from NO(3)(-)-rich surface caliche deposits near Death Valley, California. The data indicate natural ClO(4)(-) in the southwestern U.S. has a wide range of isotopic compositions that are distinct from those reported previously for natural ClO(4)(-) from the Atacama Desert of Chile as well as all known synthetic ClO(4)(-). ClO(4)(-) in Death Valley caliche has a range of high Delta(17)O values (+8.6 to +18.4 per thousand), overlapping and extending the Atacama range, indicating at least partial atmospheric formation via reaction with ozone (O(3)). However, the Death Valley delta(37)Cl values (-3.1 to -0.8 per thousand) and delta(18)O values (+2.9 to +26.1 per thousand) are higher than those of Atacama ClO(4)(-). In contrast, ClO(4)(-) from western Texas and New Mexico has much lower Delta(17)O (+0.3 to +1.3 per thousand), with relatively high delta(37)Cl (+3.4 to +5.1 per thousand) and delta(18)O (+0.5 to +4.8 per thousand), indicating either that this material was not primarily generated with O(3) as a reactant or that the ClO(4)(-) was affected by postdepositional O isotope exchange. High Delta(17)O values in ClO(4)(-) (Atacama and Death Valley) are associated with high Delta(17)O values in NO(3)(-), indicating that both compounds preserve characteristics of O(3)-related atmospheric production in hyper-arid settings, whereas both compounds have low Delta(17)O values in less arid settings. Although Delta(17)O variations in terrestrial NO(3)(-) can be attributed to mixing of atmospheric (high Delta(17)O) and biogenic (low Delta(17)O) NO(3)(-), variations in Delta(17)O of terrestrial ClO(4)(-) are not readily explained in the same way. This study provides important new constraints for identifying natural sources of ClO(4)(-) in different environments by multicomponent isotopic characteristics, while presenting the possibilities of divergent ClO(4)(-) formation mechanisms and(or) ClO(4)(-) isotopic exchange in biologically active environments.


Subject(s)
Nitrates/analysis , Perchlorates/analysis , California , Chile , Environmental Monitoring/methods , Environmental Pollutants , Isotopes , Soil , Soil Pollutants/analysis , Southwestern United States , Water Pollutants/analysis , Water Pollutants, Chemical/analysis , Water Purification/methods
14.
Environ Sci Technol ; 43(18): 6934-8, 2009 Sep 15.
Article in English | MEDLINE | ID: mdl-19806723

ABSTRACT

Perchlorate (ClO4(-)) is ubiquitous in the environment. It is produced naturally by atmospheric photochemical reactions, and also is synthesized in large quantities for military, aerospace, and industrial applications. Nitrate-enriched salt deposits of the Atacama Desert (Chile) contain high concentrations of natural ClO4(-), and have been exported worldwide since the mid-1800s for use in agriculture. The widespread introduction of synthetic and agricultural ClO4(-) into the environment has contaminated numerous municipal water supplies. Stable isotope ratio measurements of Cl and O have been applied for discrimination of different ClO4(-) sources in the environment. This study explores the potential of 36Cl measurements for further improving the discrimination of ClO4(-) sources. Groundwater and desert soil samples from the southwestern United States (U.S.) contain ClO4(-) having high 36Cl abundances (36Cl/Cl = 3100 x 10(-15) to 28,800 x 10(-15)), compared with those from the Atacama Desert (36Cl/Cl = 0.9 x 10(-15) to 590 x 10(-15)) and synthetic ClO4(-) reagents and products (36Cl/Cl = 0.0 x 10(-15) to 40 x 10(-15)). In conjunction with stable Cl and O isotope ratios, 36Cl data provide a clear distinction among three principal ClO4(-) source types in the environment of the southwestern U.S.


Subject(s)
Chlorine/chemistry , Perchlorates/chemistry , Radioactive Tracers , Radioisotopes/chemistry , Chile , Desert Climate , Nitrates/chemistry , Soil , Tritium , Water Pollutants, Chemical/analysis , Water Supply
15.
J Opt Soc Am A Opt Image Sci Vis ; 25(8): 2011-7, 2008 Aug.
Article in English | MEDLINE | ID: mdl-18677363

ABSTRACT

This paper presents a new formulation of the 3D Kirchhoff approximation that allows calculation of the scattering of vector waves from 2D rough surfaces containing structures with infinite slopes. This type of surface has applications, for example, in remote sensing and in testing or imaging of printed circuits. Some preliminary calculations for rectangular-shaped grooves in a plane are presented for the 2D surface method and are compared with the equivalent 1D surface calculations for the Kirchhoff and integral equation methods. Good agreement is found between the methods.

16.
J Pediatr ; 148(3): 392-5, 2006 Mar.
Article in English | MEDLINE | ID: mdl-16615975

ABSTRACT

Tracheal stenosis caused by complete tracheal rings has previously not been associated with Down syndrome. We identified 7 children with Down syndrome and complete tracheal rings. We found the clinical presentation and airway anatomy to be variable, advocating a heightened level of suspicion when evaluating a child with Down syndrome.


Subject(s)
Down Syndrome/complications , Trachea/abnormalities , Child, Preschool , Female , Humans , Infant , Infant, Newborn , Male , Retrospective Studies , Trachea/surgery , Tracheal Stenosis/etiology , Tracheal Stenosis/surgery
17.
Appl Opt ; 44(5): 784-91, 2005 Feb 10.
Article in English | MEDLINE | ID: mdl-15751860

ABSTRACT

Recently a modification of the Kirchhoff approximation was presented to permit the calculation of multiple-scattered light on rough surfaces with infinite slopes. A brief description of the method, with examples of the scattering of light from rough surfaces with rectangular grooves, is presented. It is shown that, for a surface with random groove depths with a constant probability distribution of the groove depths, the backscatter intensity can increase or decrease, depending on the width of this probability distribution.

19.
Appl Opt ; 42(13): 2398-406, 2003 May 01.
Article in English | MEDLINE | ID: mdl-12737475

ABSTRACT

A simple reformulation of the double-scatter Kirchhoff approximation is presented to extend the use of this calculation method to infinitely sloped surfaces. Examples are presented for square grooves and lines on perfectly conducting surfaces. The results presented show the accuracy of the method and the errors produced by not including higher-order scattering in the calculations.

20.
Am J Trop Med Hyg ; 49(2): 181-8, 1993 Aug.
Article in English | MEDLINE | ID: mdl-8357080

ABSTRACT

Leishmania (Viannia) panamensis-specific IgE and IgA antibodies were quantified in patients with parasitologically confirmed American tegumentary leishmaniasis using a radioallergosorbent test (RAST) and an enzyme-linked immunosorbent assay (ELISA), respectively. The RAST values, presented as the mean +/- SEM percentage of total isotope added, were significantly elevated in patients having disease evolution greater than 12 months (3.14 +/- 0.91), as compared with those with an evolution time of 12 or fewer months (1.66 +/- 0.15) (P = 0.017). A separate group of patients, those with eosinophils in the biopsy specimen of their lesion, also had elevated mean RAST values (2.55 +/- 0.58) when compared with patients who did not demonstrate these cells in their biopsy specimens (1.32 +/- 0.24) (P = 0.038). Leishmania-specific IgA levels, presented as the mean +/- SEM optical density, were significantly higher for patients with mucocutaneous disease (0.40 +/- 0.03) than for patients with cutaneous disease (0.28 +/- 0.023) (P = 0.0063). Inhibition testing with homologous and heterologous antigens confirmed the specificity of these assays, and were used to assess cross-reactivity among L. (Viannia) subspecies and other kineto-plastic hemoparasites. Results demonstrate that patients with more severe forms of American tegumentary leishmaniasis, defined either as increased duration of disease or invasion of the mucosa, have elevated levels of Leishmania-specific IgE and IgA antibodies, respectively.


Subject(s)
Immunoglobulin A/blood , Immunoglobulin E/blood , Leishmania braziliensis/immunology , Leishmaniasis, Cutaneous/immunology , Leishmaniasis, Mucocutaneous/immunology , Adolescent , Adult , Animals , Antibodies, Protozoan/blood , Antibody Specificity , Antigens, Protozoan/immunology , Child , Child, Preschool , Cross Reactions , Dose-Response Relationship, Immunologic , Enzyme-Linked Immunosorbent Assay , Female , Humans , Infant , Male , Radioallergosorbent Test , Retrospective Studies
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