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1.
Pathogens ; 10(10)2021 Oct 01.
Article in English | MEDLINE | ID: mdl-34684213

ABSTRACT

Vesicular stomatitis virus (VSV) emerges periodically from its focus of endemic transmission in southern Mexico to cause epizootics in livestock in the US. The ecology of VSV involves a diverse, but largely undefined, repertoire of potential reservoir hosts and invertebrate vectors. As part of a larger program to decipher VSV transmission, we conducted a study of the spatiotemporal dynamics of Simulium black flies, a known vector of VSV, along the Rio Grande in southern New Mexico, USA from March to December 2020. Serendipitously, the index case of VSV-Indiana (VSIV) in the USA in 2020 occurred at a central point of our study. Black flies appeared soon after the release of the Rio Grande's water from an upstream dam in March 2020. Two-month and one-year lagged precipitation, maximum temperature, and vegetation greenness, measured as Normalized Difference Vegetation Index (NDVI), were associated with increased black fly abundance. We detected VSIV RNA in 11 pools comprising five black fly species using rRT-PCR; five pools yielded a VSIV sequence. To our knowledge, this is the first detection of VSV in the western US from vectors that were not collected on premises with infected domestic animals.

2.
Front Microbiol ; 11: 531756, 2020.
Article in English | MEDLINE | ID: mdl-33193121

ABSTRACT

Predictive biogeochemical modeling requires data-model integration that enables explicit representation of the sophisticated roles of microbial processes that transform substrates. Data from high-resolution organic matter (OM) characterization are increasingly available and can serve as a critical resource for this purpose, but their incorporation into biogeochemical models is often prohibited due to an over-simplified description of reaction networks. To fill this gap, we proposed a new concept of biogeochemical modeling-termed substrate-explicit modeling-that enables parameterizing OM-specific oxidative degradation pathways and reaction rates based on the thermodynamic properties of OM pools. Based on previous developments in the literature, we characterized the resulting kinetic models by only two parameters regardless of the complexity of OM profiles, which can greatly facilitate the integration with reactive transport models for ecosystem simulations by alleviating the difficulty in parameter identification. The two parameters include maximal growth rate (µmax) and harvest volume (Vh) (i.e., the volume that a microbe can access for harvesting energy). For every detected organic molecule in a given sample, our approach provides a systematic way to formulate reaction kinetics from chemical formula, which enables the evaluation of the impact of OM character on biogeochemical processes across conditions. In a case study of two sites with distinct OM thermodynamics using ultra high-resolution metabolomics datasets derived from Fourier transform ion cyclotron resonance mass spectrometry analyses, our method predicted how oxidative degradation is primarily driven by thermodynamic efficiency of OM consistent with experimental rate measurements (as shown by correlation coefficients of up to 0.61), and how biogeochemical reactions can vary in response to carbon and/or oxygen limitations. Lastly, we showed that incorporation of enzymatic regulations into substrate-explicit models is critical for more reasonable predictions. This result led us to present integrative biogeochemical modeling as a unifying framework that can ideally describe the dynamic interplay among microbes, enzymes, and substrates to address advanced questions and hypotheses in future studies. Altogether, the new modeling concept we propose in this work provides a foundational platform for unprecedented predictions of biogeochemical and ecosystem dynamics through enhanced integration with diverse experimental data and extant modeling approaches.

3.
Mol Phylogenet Evol ; 75: 138-48, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24602987

ABSTRACT

A molecular phylogeny was inferred for the 22 nominal species of black flies in the Simulium jenningsi species group, which includes major pests of humans and livestock in North America. Females are structurally monomorphic, presenting a problem for identification of the pests. For each species, we sequenced approximately two kilobases from the mitochondrial genome (ND2, Cox I, proximal one-half of Cox II) and about six kilobases from the nuclear genome (ca. 2 kilobases each from 3 rapidly evolving nuclear genes: big zinc finger [BZF], "5-intron gene" [5intG], and elongation complex protein 1 [ECP1]) and analyzed them phylogenetically using maximum likelihood and Bayesian methods. The three nuclear loci have not previously been used in phylogenetic studies. The mitochondrial region recovered 6 group members as monophyletic. BZF, 5intG, and ECP1 sequences each permitted identification of 13 species and recovered the S. fibrinflatum and S. taxodium subgroups. Simulium aranti Stone and Snoddy and S. luggeri Nicholson and Mickel were consistently recovered at the base of the group. Simulium ozarkense Moulton and Adler, S. dixiense Stone and Snoddy, S. krebsorum Moulton and Adler, and S. haysi Stone and Snoddy branched off before two well-supported sister groups of the remaining species. This remainder consisted of species occupying slow, sandy lowland streams-S. definitum Moulton and Adler, S. jonesi Stone and Snoddy, and the S. taxodium subgroup (S. taxodium Snoddy and Beshear, S. chlorum Moulton and Adler, S. confusum Moulton and Adler, and S. lakei Snoddy)-as sister to two clades of species inhabiting swift, rocky upland streams-the S. fibrinflatum subgroup (S. fibrinflatum Twinn, S. notiale Stone and Snoddy, and S. snowi Stone and Snoddy) and a clade comprised of S. anchistinum Moulton and Adler, S. jenningsi Malloch, and S. nyssa Stone and Snoddy, plus species having cocoons without anterolateral apertures (S. infenestrum Moulton and Adler, S. podostemi Snoddy, S. penobscotense Snoddy and Bauer, and S. remissum Moulton and Adler). Simulium snowi Stone and Snoddy is here considered a synonym of S. notiale Stone and Snoddy. Trees inferred from BZF and 5intG were largely concordant with those from ECP1, but slightly less resolved. Combining mitochondrial and nuclear data sets did not greatly improve the performance of the ECP1 data set alone. We, therefore, propose ECP1 as the gold standard for identification of members of the S. jenningsi group. Maximum likelihood analysis of combined sequences from all three nuclear genes, with three morphological constraints imposed, yielded a tree proposed as the best hypothesis of relationships among group members, based on all available data.


Subject(s)
Evolution, Molecular , Genes, Insect , Phylogeny , Simuliidae/classification , Animals , Bayes Theorem , Carrier Proteins/genetics , Cell Nucleus/genetics , DNA, Mitochondrial/genetics , Female , Genetic Loci , Likelihood Functions , North America , Sequence Analysis, DNA , Simuliidae/genetics
4.
Phys Rev E Stat Nonlin Soft Matter Phys ; 86(3 Pt 2): 036701, 2012 Sep.
Article in English | MEDLINE | ID: mdl-23031047

ABSTRACT

This work focuses on an improved multicomponent interparticle-potential lattice Boltzmann model. The model results in viscosity-independent equilibrium densities and is capable of simulating kinematic viscosity ratios greater than 1000. External forces are incorporated into the discrete Boltzmann equation, rather than through an equilibrium velocity shift as in the original Shan and Chen (hereafter, SC) model. The model also requires the derivation of a momentum conserving effective velocity, which is substituted into the equilibrium distribution function and applies to both the single- and multiple-relaxation-time formulations. Additionally, higher-order isotropy is used in the calculation of the fluid-fluid interaction forces to reduce the magnitude of spurious currents (i.e., numerical errors) in the vicinity of interfaces. First, we compare the model to the SC model for static bubble simulations. We demonstrate that the model results in viscosity-independent equilibrium bubble densities for a wide range of kinematic viscosities, which is not the case for the SC model. Furthermore, we show that the model is capable of simulating stable bubbles for kinematic viscosity ratios greater than 1000 (when higher-order isotropy is used), whereas the SC model is known to be limited to kinematic viscosity ratios on the order of 10. Next we verify the model for surface tension via Laplace's law and show that the model results in the same surface tension values for a range of kinematic viscosities and kinematic viscosity ratios of 10, 100, and 1000. The model is also verified for layered cocurrent flow though parallel plates. We show that the simulated velocity profiles preserve continuity at the interface for kinematic viscosity ratios ranging from 0.001 to 1000 and that the model accurately predicts nonwetting and wetting phase relative permeability for kinematic viscosity ratios of 0.01 to 100.


Subject(s)
Algorithms , Models, Chemical , Rheology/methods , Solutions/chemistry , Viscosity , Computer Simulation
5.
Br J Pharmacol ; 161(5): 986-1001, 2010 Nov.
Article in English | MEDLINE | ID: mdl-20977451

ABSTRACT

BACKGROUND AND PURPOSE: The use of opioids in treating pain is limited due to significant side effects including somnolence, constipation, analgesic tolerance, addiction and respiratory depression. Pre-clinical studies have shown that neurokinin 1 (NK(1) ) receptor antagonists block opioid-induced antinociceptive tolerance and may inhibit opioid-induced rewarding behaviours. Here, we have characterized a bifunctional peptide with both opioid agonist and NK(1) antagonist pharmacophores in a rodent model of neuropathic pain. EXPERIMENTAL APPROACH: Rats were evaluated for behavioural responses to both tactile and thermal stimuli in either an uninjured, sham- or nerve-injured state. TY005 (Tyr-DAla-Gly-Phe-Met-Pro-Leu-Trp-O-3,5-Bn(CF(3) )(2) ) was delivered spinally or systemically to assess the antinociceptive effects after acute exposure. Motor skills were evaluated using the rotarod test to determine potential sedative effects. Spinal TY005 was given chronically to sham- or nerve-injured animals to determine the development of tolerance. KEY RESULTS: Bolus injections of TY005 produced dose-dependent antinociception in non-injured animals and alleviated nerve injury-induced thermal and tactile hypersensitivities (i.e. antihyperalgesia) more effectively than morphine. Sedative effects were not evident from the rotarod test at doses that were antihyperalgesic, nor at doses threefold higher. Repeated administration of TY005 did not lead to the development of antihyperalgesic tolerance or alter sensory thresholds. CONCLUSIONS AND IMPLICATIONS: Collectively, the data suggest that opioid agonist/NK(1) antagonist bifunctional peptides represent a promising novel approach to the management of chronic pain without the development of tolerance, reducing the need for escalation of doses and unwanted side effects associated with opiates alone.


Subject(s)
Analgesics, Opioid/pharmacology , Drug Tolerance , Neuralgia/drug therapy , Oligopeptides/pharmacology , Analgesics, Opioid/administration & dosage , Analgesics, Opioid/adverse effects , Animals , Behavior, Animal/drug effects , Disease Models, Animal , Dose-Response Relationship, Drug , Injections, Intravenous , Injections, Spinal , Male , Motor Skills/drug effects , Neuralgia/physiopathology , Neurokinin-1 Receptor Antagonists , Oligopeptides/administration & dosage , Oligopeptides/adverse effects , Pain Measurement , Rats , Rats, Sprague-Dawley , Receptors, Opioid/agonists
6.
Arch Virol ; 154(12): 1909-16, 2009.
Article in English | MEDLINE | ID: mdl-19838620

ABSTRACT

Triple gene block 1 (TGB1) and coat protein (CP) sequences of 30 hosta virus X (HVX) isolates from Tennessee (TN), USA, were determined and compared with available sequences in GenBank. The CPs of all known HVX isolates, including those from TN, shared 98.3-100% and 98.2-100% nucleotide and amino acid sequence identity, respectively, whereas TGB1 shared 97.4-100% nucleotide and 97-100% amino acid sequence identity. TGB1 of TN isolates were all longer by one codon from that of a Korean isolate, which is the only sequence publicly available. Phylogenetic analysis of nucleotide and amino acid sequences of TGB1 and CP of all known HVX isolates, separately or combined, revealed a close relationship, suggesting that all of them are derived from a common ancestor. Phylogenetic analysis with the type member of each genus of the family Flexiviridae confirmed that HVX is a member of a distinct species of the genus Potexvirus.


Subject(s)
Genetic Variation , Hosta/virology , Phylogeny , Plant Diseases/virology , Potexvirus , Capsid Proteins/genetics , Molecular Sequence Data , Potexvirus/classification , Potexvirus/genetics , Potexvirus/isolation & purification , Sequence Analysis, DNA , Species Specificity , Tennessee , Viral Proteins/genetics
7.
J Invertebr Pathol ; 98(3): 267-70, 2008 Jul.
Article in English | MEDLINE | ID: mdl-18442830

ABSTRACT

Seed application of Beauveria bassiana 11-98 resulted in endophytic colonization of tomato and cotton seedlings and protection against plant pathogenic Rhizoctonia solani and Pythium myriotylum. Both pathogens cause damping off of seedlings and root rot of older plants. The degree of disease control achieved depended upon the population density of B. bassiana conidia on seed. Using standard plating techniques onto selective medium, endophytic 11-98 was recovered from surface-sterilized roots, stems, and leaves of tomato, cotton, and snap bean seedlings grown from seed treated with B. bassiana 11-98. As the rate of conidia applied to seed increased, the proportion of plant tissues from which B. bassiana 11-98 was recovered increased. For rapid detection of B. bassiana 11-98 in cotton tissues, we developed new ITS primers that produce a PCR product for B. bassiana 11-98, but not for cotton. In cotton samples containing DNA from B. bassiana11-98, the fungus was detected at DNA ratios of 1:1000; B. bassiana 11-98 was detected also in seedlings grown from seed treated with B. bassiana 11-98. Using SEM, hyphae of B. bassiana11-98 were observed penetrating epithelial cells of cotton and ramifying through palisade parenchyma and mesophyll leaf tissues. B. bassiana11-98 induced systemic resistance in cotton against Xanthomonas axonopodis pv. malvacearum (bacterial blight). In parasitism assays, hyphae of B. bassiana 11-98 were observed coiling around hyphae of Pythium myriotylum.


Subject(s)
Beauveria/pathogenicity , Mitosporic Fungi/physiology , Pest Control, Biological/methods , Plant Diseases/microbiology , Beauveria/genetics , DNA, Fungal/analysis , DNA, Fungal/genetics , Fabaceae/microbiology , Gossypium/microbiology , Hyphae/ultrastructure , Solanum lycopersicum/microbiology , Mitosporic Fungi/ultrastructure , Plant Leaves/microbiology , Plant Leaves/ultrastructure , Polymerase Chain Reaction , Seedlings/microbiology
8.
Proc Inst Mech Eng H ; 222(1): 29-39, 2008 Jan.
Article in English | MEDLINE | ID: mdl-18335716

ABSTRACT

The objective of this study was to determine tibiofemoral cartilage thickness distribution, and to investigate the relationship between cartilage geometry and anthropometric variables. In this study, 20 magnetic resonance examinations of the knee from normal individuals were reconstructed to provide three-dimensional models of the knee joint, including bony and cartilage surfaces. Three regions were defined on the articular surface, and the cartilage thickness distribution along each of these was determined. Statistically significant differences between femoral and tibial regions were examined using the paired Student t test in Microsoft Excel. Correlations were investigated using the correlation tool in Microsoft Excel. The average tibial cartilage thickness was found to be 2.76 mm and the average femoral cartilage thickness was 2.75 mm. Significant correlations exist between the tibia cartilage thickness and body height (R = 0.60; P < 0.05) and weight (R = 0.64; P < 0.05). Significant correlations exist between the femoral cartilage volume and the body height (R = 0.736; P < 0.01) and weight (R = 0.855; P < 0.01). It is suggested that the distribution and correlations of cartilage distribution indicate adaptation in response to mechanical loading. Information regarding cartilage thickness and volume distribution as found in this study may be useful in diagnosing and monitoring cartilage loss in patients with degenerative joint disease.


Subject(s)
Anthropometry/methods , Body Size/physiology , Menisci, Tibial/anatomy & histology , Menisci, Tibial/physiology , Models, Anatomic , Models, Biological , Adult , Computer Simulation , Data Interpretation, Statistical , Female , Humans , Male , Models, Statistical , Reproducibility of Results , Sensitivity and Specificity , Statistical Distributions , Statistics as Topic
9.
Mycopathologia ; 161(2): 93-9, 2006 Feb.
Article in English | MEDLINE | ID: mdl-16463092

ABSTRACT

Aspergillus flavus is a filamentous fungus that produces mycotoxins in many food and feed crops, such as maize (Zea mays L.). Isolates were analyzed for toxin production by nucleic acid profiles in an attempt to differentiate aflatoxigenic from nonaflatoxigenic isolates. A total of 41 aflatoxigenic and 34 nonalfatoxigenic isolates were included in the study. The isolates were evaluated initially using DNA amplification fingerprinting (DAF) without clear resolution of the groups. A weak association of aflatoxigenic isolates was observed, as evidenced by their clustering in 18 of 81 trees recovered from maximum parsimony analysis of binary characters derived from arbitrary signatures from amplification profiles (ASAP) data; nonaflatoxigenic isolates exhibited a pattern of paraphyletic laddering. Up to five markers unambiguously supported the aflatoxigenic isolate grouping, but the presence of alternative conflicting topologies in equally parsimonious trees precluded the observation of meaningful statistical support. With additional markers for genome of A. flavus, this method could be used to resolve toxigenic from nontoxigenic strains. This additional work could resolve aflatoxigenic isolates of A. flavus present on maize plants using ASAP, which would reduce labor intense costs and potentially lead to faster determination of resistant cultivars in breeding efforts.


Subject(s)
Aflatoxins/biosynthesis , Aspergillus flavus/metabolism , DNA Fingerprinting/methods , Zea mays/microbiology , Aflatoxins/genetics , Aspergillus flavus/classification , Aspergillus flavus/genetics , DNA, Fungal/chemistry , DNA, Fungal/genetics , DNA, Ribosomal Spacer/chemistry , DNA, Ribosomal Spacer/genetics , Polymerase Chain Reaction , Polymorphism, Restriction Fragment Length
10.
J Wildl Dis ; 41(2): 354-62, 2005 Apr.
Article in English | MEDLINE | ID: mdl-16107670

ABSTRACT

Blue jays (Cyanocitta cristata) are an effective indicator species for West Nile virus (WNV) and may be regionally important in surveillance efforts. The sites of WNV replication and sensitivity of virus detection techniques are undefined for blue jays. The objectives of this study were to describe the gross and microscopic pathology associated with natural WNV infection in blue jays, as well as determine the most appropriate tissues to be used for virus isolation, reverse transcription-nested polymerase chain reaction, and immunohistochemistry (IHC) techniques. Blue jays were collected in Georgia, USA, between May and September 2001. Initial screening by virus isolation indicated that 36 of 59 blue jays chosen for evaluation were WNV positive. From this group, 20 positive and five negative birds were chosen to compare virus detection techniques. Six positive and five negative birds were selected for histopathology examination. Splenomegaly and poor body condition were the most consistent gross findings among positive birds. The most consistent histopathologic findings in the tissues of WNV-positive blue jays were mononuclear leukocytosis and epicarditis/myocarditis. Brain, heart, and lung had the highest viral titers, and WNV antigen was most often detected by IHC in heart, kidney, liver, and lung. Reverse transcription-nested polymerase chain reaction proved to be the most sensitive diagnostic test applied in this study irrespective of the tissue type. Brain tissue could be used effectively for both virus isolation and RT-nPCR, and this tissue is simple to remove and process. The success of IHC is highly dependent on tissue selection, and the use of multiple tissues including heart, kidney, liver, or lung is recommended.


Subject(s)
Bird Diseases/pathology , Songbirds/virology , West Nile Fever/veterinary , West Nile virus/isolation & purification , Animals , Bird Diseases/diagnosis , Bird Diseases/epidemiology , Bird Diseases/virology , Female , Georgia/epidemiology , Immunohistochemistry/veterinary , Male , Organ Specificity , Reverse Transcriptase Polymerase Chain Reaction/veterinary , Splenomegaly/diagnosis , Splenomegaly/epidemiology , Splenomegaly/pathology , Splenomegaly/veterinary , Viral Load/veterinary , West Nile Fever/diagnosis , West Nile Fever/epidemiology , West Nile Fever/pathology
11.
Radiol Clin North Am ; 38(2): 345-74, 2000 Mar.
Article in English | MEDLINE | ID: mdl-10765394

ABSTRACT

Percutaneous image-guided catheter drainage with adjunctive ICFT has become the mainstay in the treatment of complicated pleural fluid collections. There are six basic principles of image-guided drainage and ICFT that must be understood to maximize the efficacy and safety of the procedure. 1. There must be a basic understanding of why traditional nonguided thoracostomy drainage fails in a significant percentage of patients. Tube malposition relative to fluid loculations, fluid debris and viscosity, and the presence of a stage 3 pleural peel are the primary reasons for failure. Image-guided placement of drains addresses the issue of tube malposition and ICFT greatly facilitates drainage of fibrinous fluid. 2. Proper use of cross-sectional imaging is one of the keys to ultimate success. CT and ultrasound allow very accurate assessment of the underlying pathologic process and are crucial in planning the drainage procedure, guiding the actual placement of drains, and following the course and outcome of treatment. The added costs of cross-sectional imaging are more than compensated by the increase in success of the drainage procedure. 3. Aggressive catheter management is the single most important factor in success. Multiple loculations require multiple catheters for adequate drainage. Pleural adhesions may form quickly as drainage progresses leading to the formation of undrained loculations. Frequent cross-sectional imaging is needed to detect undrained loculations so that additional drainage catheters may be placed if needed. It is crucial that the drainage catheter always be properly positioned in relation to fluid loculations. 4. Intracavitary fibrinolytic therapy is a very powerful adjunctive therapy to aid in complete evacuation of fluid collections that contain fibrin nets and debris. It can also partially débride the pleural surfaces of fibrinous debris and facilitate complete re-expansion of the underlying lung. Intracavitary fibrinolytic therapy should not be used in an attempt to salvage success by a malpositioned chest tube. 5. The ultimate success of closed drainage for complicated pleural fluid collections is closely related to the age of the effusion at the time of drainage. A very high rate of clinical success may be expected when these techniques are used in the treatment of stage 2 fibrinopurulent effusions. If drainage is delayed until the third stage (fibrous pleural peel formation) then closed drainage likely will fail and a formal thoracotomy and decortication will be necessary. Experience in the literature suggests that effusions up to 4 to 6 weeks in duration may be drained successfully but those older than 6 weeks likely will have an associated pleural peel. Effective pleural drainage must be instituted early in the course of the disease process. 6. There may be significant residual pleural and parenchymal inflammatory changes after complete drainage of a stage 2 effusion. If the fluid in the pleural space has been adequately drained and the visceral and parietal pleural surfaces apposed, then the residual inflammatory pleural thickening and associated lung consolidation resolve over 2 to 4 months and pulmonary function returns to baseline. Imaging studies immediately after complete pleural drainage are not normal. These residual abnormalities should not be interpreted as evidence that open surgical drainage should have been performed. Effective closed drainage carries lower morbidity, mortality, and cost than does open surgical drainage. For radiologists and clinicians alike it does not suffice simply to place one or more thoracostomy tubes, round daily, and hope that the occasional use of fibrinolytic agents does the rest. Without a more aggressive approach to catheter position and management the efficacy is no greater than that historically seen with nonguided closed drainage and surgeons will continue to plead for earlier effective open drainage.


Subject(s)
Pleural Effusion/diagnostic imaging , Pleural Effusion/therapy , Radiography, Interventional/methods , Tomography, X-Ray Computed/methods , Catheterization/methods , Combined Modality Therapy , Drainage/methods , Fibrinolytic Agents/administration & dosage , Humans , Pleural Effusion/complications , Thoracostomy/methods , Thrombolytic Therapy/methods , Treatment Outcome
12.
Biochemistry ; 38(22): 7294-306, 1999 Jun 01.
Article in English | MEDLINE | ID: mdl-10353841

ABSTRACT

Significant differences exist between mammals and fungi with respect to glycosphingolipid (GSL) structure and biosynthesis. Thus, these compounds, as well as the cellular machinery regulating their expression, have considerable potential as targets for the diagnosis and treatment of fungal diseases. In this study, the major neutral GSL components extracted from both yeast and mycelium forms of the thermally dimorphic mycopathogen Paracoccidioides brasiliensis were purified and characterized by 1H and 13C NMR spectroscopy, ESI-MS and ESI-MS/CID-MS, and GC-MS. The major GSLs of both forms were identified as beta-glucopyranosylceramides (GlcCer) having (4E, 8E)-9-methyl-4,8-sphingadienine as long chain base in combination with either N-2'-hydroxyoctadecanoate or N-2'-hydroxy-(E)-3'-octadecenoate. The mycelium form GlcCer had both fatty acids in a approximately 1:1 ratio, while that of the yeast form had on average only approximately 15% of the (E)-Delta 3-unsaturated fatty acid. Cerebrosides from two strains of Aspergillus fumigatus (237 and ATCC 9197) expressing both GalCer and GlcCer were also purified and characterized by similar methods. The GalCer fractions were found to have approximately 70% and approximately 90% N-2'-hydroxy-(E)-3'-octadecenoate, respectively, in the two strains. In contrast, the GlcCer fractions had N-2'-hydroxy-(E)-3'-octadecenoate at only approximately 20 and approximately 50%, respectively. The remainder in all cases was the saturated 2-OH fatty acid, which has not been previously reported in cerebrosides from A. fumigatus. The availability of detailed structures of both glycosylinositol phosphorylceramides [Levery, S. B., Toledo, M. S., Straus, A. H., and Takahashi, H. K. (1998) Biochemistry 37, 8764-8775] and cerebrosides from P. brasiliensis revealed parallel quantitative differences in expression between yeast and mycelium forms, as well as a striking general partitioning of ceramide structure between the two classes of GSLs. These results are discussed with respect to possible functional roles for fungal sphingolipids, particularly as they relate to the morphological transitions exhibited by P. brasiliensis.


Subject(s)
Aspergillus fumigatus/chemistry , Fatty Acids, Unsaturated/biosynthesis , Glycosphingolipids/chemistry , Paracoccidioides/chemistry , Acylation , Aspergillus fumigatus/metabolism , Aspergillus fumigatus/pathogenicity , Carbohydrate Sequence , Fatty Acids/chemistry , Fatty Acids, Unsaturated/chemistry , Galactosylceramides/metabolism , Glucosylceramides/chemistry , Mass Spectrometry , Molecular Sequence Data , Nuclear Magnetic Resonance, Biomolecular , Paracoccidioides/metabolism , Paracoccidioides/pathogenicity
13.
Semin Respir Infect ; 14(1): 59-72, 1999 Mar.
Article in English | MEDLINE | ID: mdl-10197398

ABSTRACT

The basic principles of empyema management center on the initiation of antibiotics and effective pleural space drainage. For patients with empyemas in the exudative or fibrinopurulent stage, image-guided chest tubes have markedly improved patient care. These catheters can be placed into ideal positions within the chest by the use of various imaging techniques to promote effective drainage. Because of a minimal need for tissue dissection, patients tolerate image-guided catheters well with only local anesthetics. Multiple techniques exist to augment tube drainage if necessary. Available approaches include tube exchange with placement of a larger-caliber catheter, tube manipulation, and fibrinolytic therapy. However, success of image-guided catheters depends on proper patient selection, the skills of the operator, and the ability to monitor daily chest tube function to ensure adequacy of drainage. Open surgical procedures can be avoided in most treated patients.


Subject(s)
Drainage , Empyema, Pleural/diagnostic imaging , Empyema, Pleural/surgery , Thoracostomy , Chest Tubes , Drainage/methods , Humans , Thoracostomy/methods , Tomography, X-Ray Computed/methods
14.
J Clin Psychol ; 54(8): 1017-27, 1998 Dec.
Article in English | MEDLINE | ID: mdl-9840774

ABSTRACT

Comparing 36 disruptive behavior-disordered and 40 normal female adolescents, we found higher levels of anxiety and poorer performance on a measure of verbal fluency in the clinical sample. No group differences were found on a nonverbal measure of reflectivity nor on a measure of interpersonal cognitive problem solving. Nor was evidence found for an hypothesized anxiety-related performance decrement among disruptive behavior-disordered youth. However, anxiety induction facilitated performance across groups on interpersonal cognitive problem solving.


Subject(s)
Adolescent Behavior , Anxiety Disorders/psychology , Attention Deficit and Disruptive Behavior Disorders/psychology , Cognition , Adolescent , Child , Female , Humans , Problem Solving
15.
J Nucl Med ; 39(4): 659-63, 1998 Apr.
Article in English | MEDLINE | ID: mdl-9544677

ABSTRACT

UNLABELLED: Rhenium-188 (tin) hydroxyethylidine diphosphonate [188Re(Sn)HEDP] is a new radiopharmaceutical that localizes in skeletal metastases and emits beta particles that may be therapeutically beneficial. METHODS: It was evaluated by in vitro and in vivo testing in the laboratory, in animals and in humans using 188Re from a variety of sources. It may be produced by a desk-top method developed previously for 186Re(Sn)HEDP using 188Re produced through neutron irradiation of either enriched 187Re or naturally occurring rhenium targets or the use of a 188W/188Re generator. RESULTS: So long as the mass of rhenium in the 188Re-perrhenate to be processed into 188Re(Sn)HEDP is at least 100 microg, satisfactory radiochemical yields and purity may be obtained by all methods. The 188Re(Sn)HEDP has biodistribution and radiation dosimetry characteristics that are similar to those noted previously for 186Re(Sn)HEDP and appears to result in similar benefits and toxicities in patients with skeletal metastases. External radiation exposure monitoring indicates that, only 4 hr after a therapeutic administration of 1110 MBq (30 mCi) of 188Re(Sn)HEDP, average exposure rates at 1 meter from the patient would be only 0.5 mR/hr. CONCLUSION: Same-day, on-demand, outpatient therapy of disseminated skeletal metastases appears to be feasible with 188Re(Sn)HEDP.


Subject(s)
Bone Neoplasms/radiotherapy , Bone Neoplasms/secondary , Etidronic Acid/therapeutic use , Organometallic Compounds/therapeutic use , Aged , Animals , Bone Neoplasms/complications , Etidronic Acid/pharmacokinetics , Etidronic Acid/toxicity , Humans , Male , Middle Aged , Organometallic Compounds/pharmacokinetics , Organometallic Compounds/toxicity , Pain/etiology , Prostatic Neoplasms/pathology , Radionuclide Generators , Radiotherapy Dosage , Rats , Sheep
18.
Am J Hypertens ; 9(10 Pt 1): 1040-3, 1996 Oct.
Article in English | MEDLINE | ID: mdl-8896659

ABSTRACT

We report a case of a single intrahepatic pheochromocytoma in the absence of an adrenal lesion and no evidence of metastatic disease. The patient had strong clinical and biochemical evidence of a pheochromocytoma. A CT scan was abnormal but nondiagnostic for pheochromocytoma. An 123I-metaiodobenzyl guanidine (MIBG) scan was falsely negative, but an MRI scan showed a definitive hepatic abnormality. After confirmation of endocrine activity by venous sampling, the tumor was surgically removed. The patient's symptoms have resolved and her plasma catecholamine levels as well as her 24-h urine catecholamine excretion have normalized. The case shows an unusual location of an isolated pheochromocytoma and provides an example of a false negative I-123 MIBG scan.


Subject(s)
Liver Neoplasms/pathology , Pheochromocytoma/pathology , Adult , Female , Humans , Liver Neoplasms/diagnosis , Magnetic Resonance Imaging , Pheochromocytoma/diagnosis
19.
Health Psychol ; 15(3): 226-9, 1996 May.
Article in English | MEDLINE | ID: mdl-8698037

ABSTRACT

Factors predicting participant attrition in a community-based, culturally specific smoking-cessation program enrolling 93 Hispanic smokers were examined. Analysis of univariate predictors showed noncompleters (n = 18) to have lower incomes, to have expressed greater initial confidence in their ability to stop smoking, and to have perceived themselves to be in poorer general health and poorer health in relation to peers, than completers. Noncompleters were also more likely to have reported cardiovascular problems. Multivariate logistic regression analysis showed that confidence in stopping smoking, health compared with that of peers, and reported cardiovascular problems contributed significantly to prediction while controlling for other significant univariate predictors. The results are discussed in terms of factors that might mitigate premature termination in community-based smoking-cessation interventions targeting Hispanic smokers.


Subject(s)
Community Health Services , Hispanic or Latino , Patient Dropouts , Smoking Cessation/ethnology , Adult , Caribbean Region/ethnology , Central America/ethnology , Female , Health Status , Humans , Logistic Models , Male , Middle Aged , New York City , Patient Dropouts/psychology , Smoking Cessation/statistics & numerical data , Socioeconomic Factors , South America/ethnology
20.
Chest ; 108(5): 1252-9, 1995 Nov.
Article in English | MEDLINE | ID: mdl-7587425

ABSTRACT

STUDY OBJECTIVE: We report the results of image-guided catheter drainage with adjunctive enzymatic pleural debridement in the treatment of empyemas and other complicated pleural fluid collections. DESIGN: Retrospective review. PATIENTS: One hundred eighteen patients with complicated pleural fluid collections were treated with image-guided drainage. There were 79 empyemas, 27 sterile loculated parapneumonic effusions, 10 sterile hemothoraces, and 2 sterile postoperative exudative effusions. Forty-one patients had failed prior large-bore thoracostomy drainage. The estimated age of the effusions at the time of image-guided drainage ranged from 1 to 175 days with a mean estimated age of 13 days. INTERVENTIONS: Patients were treated with image-guided placement of one or more 12F to 16F chest drains. Adjunctive urokinase instillation was used in 98 cases. Urokinase (100,000 to 250,000 U/mL) was instilled in 20 to 240-mL aliquots and reaspirated in 1 to 4 h. One to four instillations were performed per day until drainage was complete. MEASUREMENTS AND RESULTS: Drainage was successful in 111 cases (94%). Two patients died of sepsis with incomplete drainage. Five patients underwent decortication (three recovered and two died postoperatively). Fifty-three patients (45%) required placement of more than one drain. The mean duration of drainage was 6.3 days. Patients treated with pleurolysis required a mean of five instillations of urokinase. The mean total dose of urokinase used per case was 466,000 U. There were no complications. CONCLUSION: Image-guided drainage with adjunctive pleural urokinase therapy is a safe and effective method of closed thoracostomy drainage of complicated pleural fluid collections and can obviate surgery in most cases.


Subject(s)
Drainage , Plasminogen Activators/therapeutic use , Pleural Effusion/therapy , Thoracostomy , Thrombolytic Therapy , Urokinase-Type Plasminogen Activator/therapeutic use , Adolescent , Adult , Aged , Aged, 80 and over , Chest Tubes , Child , Combined Modality Therapy , Empyema, Pleural/diagnostic imaging , Empyema, Pleural/drug therapy , Empyema, Pleural/surgery , Female , Humans , Male , Middle Aged , Pleural Effusion/diagnostic imaging , Pleural Effusion/drug therapy , Pleural Effusion/surgery , Retrospective Studies , Tomography, X-Ray Computed , Treatment Outcome
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