- NIOSH
1095 Willowdale Road
Morgantown, WV
Donald Beezhold
West Virginia University, Microbiology, Immunology and Cell Biology, Department Member
Influenza A virus (IAV) infection remains a significant cause of morbidity and mortality worldwide. One key transcription factor that is activated upon IAV infection is nuclear factor Kappa B (NF-κB). NF-κB regulation involves the... more
Influenza A virus (IAV) infection remains a significant cause of morbidity and mortality worldwide. One key transcription factor that is activated upon IAV infection is nuclear factor Kappa B (NF-κB). NF-κB regulation involves the inhibitor proteins NF-κB inhibitor beta (NFKBIB), (also known as IκB β), which form complexes with NF-κB to sequester it in the cytoplasm. In this study, microarray data showed differential expression of several microRNAs (miRNAs) on exposure to IAV. Target scan analysis revealed that miR-4776, miR-4514 and miR-4742 potentially target NFKBIB messenger RNA (mRNA). Time-course analysis of primary bronchial epithelial cells (HBEpCs) showed that miR-4776 expression is increased within 1 h of infection, followed by its downregulation 4 h post-exposure to IAV. NFKBIB upregulation of miR-4776 correlated with a decrease in NFKBIB expression within 1 h of infection and a subsequent increase in NFKBIB expression 4 h post-infection. In addition, miRNA ago-immunopreci...
Research Interests:
Research Interests:
MicroRNAs (miRNAs) are essential regulators of gene expression in humans and can control pathogenesis and host–virus interactions. Notably, the role of specific host miRNAs during influenza virus infections are still ill-defined. The... more
MicroRNAs (miRNAs) are essential regulators of gene expression in humans and can control pathogenesis and host–virus interactions. Notably, the role of specific host miRNAs during influenza virus infections are still ill-defined. The central goal of this study was to identify novel miRNAs and their target genes in response to influenza virus infections in airway epithelium. Human airway epithelial cells exposed to influenza A virus (IAV) induced several novel miRNAs that were identified using next-generation sequencing (NGS) and their target genes by biochemical methods. NGS analysis predicted forty-two RNA sequences as possible miRNAs based on computational algorithms. The expression patterns of these putative miRNAs were further confirmed using RT-PCR in human bronchial epithelial cells exposed to H1N1, H9N1(1P10), and H9N1 (1WF10) strains of influenza virus. A time-course study showed significant downregulation of put-miR-34 in H1N1 and put-miR-35 in H9N1(1P10)-infected cells, wh...
Research Interests:
Research Interests:
Hev b 5 is an acidic protein (isoelectric point, 3.5) rich in glutamic acid with 9 repeated amino acid (AA) sequences of XEEX or XEEEX. Although its function in Hevea brasiliensis is unknown, Hev b 5 has been identified as a major latex... more
Hev b 5 is an acidic protein (isoelectric point, 3.5) rich in glutamic acid with 9 repeated amino acid (AA) sequences of XEEX or XEEEX. Although its function in Hevea brasiliensis is unknown, Hev b 5 has been identified as a major latex allergen. Immunoblot inhibition studies suggest Hev b 5 exists as multiple isoforms or contains a common epitope found in several other proteins. The purpose of this study was to further characterize Hev b 5 and to identify linear IgE-binding epitopes. Octapeptides spanning the entire Hev b 5 protein were synthesized on a derivatized cellulose membrane. The membrane was reacted with sera pooled from health care workers allergic to latex or rabbits immunized with latex proteins. B-cell epitopes were identified by subsequent incubations with the appropriate secondary antibodies and detected by using chemifluorescence. Sera from patients allergic to latex recognized 6 IgE-binding regions located throughout the molecule. Two epitopes (2 and 4) had the common AA sequence of KTEEP. Epitopes 3 and 5 had a similar AA sequence of EEXXA, where X was P, T, or K. Epitopes 1 and 6 appeared to be unrelated to the other epitopes. Database analysis could not identify other proteins with similar sequences. Neither of the XEEEX sequences bound IgE. Control sera failed to react to any peptides. Hev b 5 exists as multiple isoforms, but only small amounts are present in the nonammoniated latex preparations, such as those used for diagnostic tests, and this may help to explain the relatively poor sensitivity of some in vitro tests.
Research Interests: Immunology, Western blotting, Antibodies, Allergy, Humans, and 15 moreLaTeX, Animals, Hevea brasiliensis, Allergens, Immunoglobulin E, Health Care Workers, Diagnostic Test, Rabbits, Amino Acid Sequence, Protein Binding, PLANT PROTEINS, Antigens, Glutamic Acid, immunoglobulin G, and Molecular Sequence Data
SUMMARY We have previously identified the hevein preprotein as a common allergen for latex allergic healthcare workers. The B cell epitopes in the hevein protein that are recognized by IgE of latex-allergic individuals have not been... more
SUMMARY We have previously identified the hevein preprotein as a common allergen for latex allergic healthcare workers. The B cell epitopes in the hevein protein that are recognized by IgE of latex-allergic individuals have not been identified. In this study, we examined the hevein preprotein using epitope mapping. Overlapping synthetic peptides of 10 amino acids (two aa overlap) were synthesized on a derivatized cellulose membrane using Fmoc chemistry. The peptide spots were probed with pooled sera from 10 latex-allergic patients, and the IgE-reactive peptides identified with anti-IgE MoAbs. We identified six B cell epitopes within the full length hevein preprotein which bound IgE from latex-allergic patients. Two were located in the N-terminal 5-kD hevein domain and four were observed in the 14-kD C-domain. A broad epitope was located between the N-terminal amino acids 13–24. This epitope had nearly complete homology to wheat germ agglutinin (WGA). Immunological cross-reactivity t...
Research Interests:
Exposure to soy antigens has been associated with asthma in community outbreaks and in some workplaces. Recently, 135 soy flake processing workers (SPWs) in a Tennessee facility were evaluated for immune reactivity to soy. Allergic... more
Exposure to soy antigens has been associated with asthma in community outbreaks and in some workplaces. Recently, 135 soy flake processing workers (SPWs) in a Tennessee facility were evaluated for immune reactivity to soy. Allergic sensitization to soy was common and was five times more prevalent than in health care worker controls (HCWs) with no known soy exposure. To characterize sensitization to soy allergens in SPWs. Sera that were positive to soy ImmunoCAP (n=27) were tested in IgE immunoblots. Wild-type (WT) and transgenic (TG) antigens were sequenced using nanoscale Ultra-Performance Liquid Chromatography Tandem Mass Spectrometry (nanoUPLC MS/MS). IgE reactivity towards 5-enolpyruvylshikimate-3-phosphate synthase (CP4-EPSP), a protein found in TG soy, was additionally investigated. De-identified sera from 50 HCWs were used as a control. Immunoblotting of WT and TG soy flake extracts revealed IgE against multiple soy antigens with reactivity towards 48, 54, and 62 kDa bands being the most common. The prominent proteins that bound SPW IgE were identified by nanoUPLC MS/MS analysis to be the high molecular weight soybean storage proteins, β-conglycinin (Gly m 5), and Glycinin (Gly m 6). No specific IgE reactivity could be detected to lower molecular weight soy allergens, Gly m 1 and Gly m 2, in soybean hull (SH) extracts. IgE reactivity was comparable between WT and TG extracts; however, IgE antibodies to CP4-EPSP could not be detected. SPWs with specific IgE to soy reacted most commonly with higher molecular weight soybean storage proteins compared with the lower molecular weight SH allergens identified in community asthma studies. IgE reactivity was comparable between WT and TG soy extracts, while no IgE reactivity to CP4-EPSP was observed. High molecular weight soybean storage allergens, Gly m 5 and Gly m 6, may be respiratory sensitizers in occupational exposed SPWs.
Research Interests:
The purpose of this study was to investigate crossreactivity between latex and foods, to identify crossreacting IgE binding proteins, and to assess the clinical significance. Forty-seven latex allergic patients and 46 non-latex allergic... more
The purpose of this study was to investigate crossreactivity between latex and foods, to identify crossreacting IgE binding proteins, and to assess the clinical significance. Forty-seven latex allergic patients and 46 non-latex allergic patient controls were studied. Allergen sensitization was determined by skin-prick testing (SPT) and allergenic proteins were identified by immunoblot reactivity and amino acid sequence analysis. Immunological reactivity to foods was found to be common, occurring in 33 latex-allergic individuals but in only seven controls (P < 0.000001); 100 of 376 (27%) food skin-prick tests were positive in the latex-allergic subjects. Twenty-seven out of 100 positive food SPTs were associated with clinical symptoms. Seventeen patients manifested a clinical allergy to at least one food including 11 with anaphylaxis, and 14 with local sensitivity reactions. Positive food skin tests occurred most frequently with avocado (53%), potato (40%), banana (38%), tomato (28%), chestnut (28%), and kiwi (17%). Latex-allergic patients (23%) recognize a protein that had sequence homology to a broad class of plant proteins known as patatins. Crossreactivity between latex and several potato proteins was observed by immunoblot inhibition analysis. Sensitization to latex has extensive crossreactivity with certain foods and leads to clinical allergic reactions. Potatoes and tomatoes are newly reported cross-reacting foods. Plant proteins with structural homology to latex proteins may predispose to food allergy.
Research Interests:
Research Interests:
SUMMARY Latex allergy is an occupational hazard for health care workers. Extractable latex proteins are known to be allergenic, but most latex allergens have not been specifically identified. The purpose of this study was to characterize... more
SUMMARY Latex allergy is an occupational hazard for health care workers. Extractable latex proteins are known to be allergenic, but most latex allergens have not been specifically identified. The purpose of this study was to characterize the IgE response of latex-allergic patients to latex proteins and to identify common protein allergens. Serum was obtained from 40 individuals who were skin test-positive to latex; 85% were health care workers. Western blots for IgE reactivity were performed using both ammoniated (AL) and non-ammoniated (NAL) latex proteins and IgE-reactive NAL proteins were analysed by microsequence analysis. The patients were grouped according to common patterns of reactivity. Pattern 1, the most common pattern of reactivity (9/40 patients) recognized two protein bands in both NAL and AL at 46 and 110kD. A second, heterogeneous pattern of reactivity (pattern 2) recognized a diffuse pattern of polypeptides in the AL preparation. The n-terminal amino acid sequences ...
Research Interests:
Research Interests:
Research Interests:
Cannabis cultivation is an emerging industry within the United States. Organic dust derived in part from naturally occurring microorganisms is known to cause byssinosis in the hemp industry. In this pilot study, bacteria and fungi... more
Cannabis cultivation is an emerging industry within the United States. Organic dust derived in part from naturally occurring microorganisms is known to cause byssinosis in the hemp industry. In this pilot study, bacteria and fungi encountered by workers at an outdoor cannabis farm that utilized organic practices were elucidated by 16░S ribosomal RNA (rRNA) and Internal Transcribed Spacer (ITS) region sequencing, respectively. Area (n = 14) and personal air samples (n = 12) were collected during harvesting and processing activities. 16░S rRNA and ITS regions of extracted bacterial and fungal genomic DNA were amplified and sequenced using Sanger sequencing. Bacterial sequencing resolved 1077 sequences that were clustered into 639 operational taxonomic units (OTUs) and predominantly placed in the phylum, Actinobacteria (46%). Personal air samples revealed higher bacterial and Actinobacteria diversity compared to outdoor area samples collected within the facility (p<0.05). A high deg...
Research Interests:
Research Interests: Business, Occupational Health, Agriculture, Environmental Monitoring, Nanoparticles, and 13 moreRisk assessment, Nanotechnology, Medicine, Humans, Animals, Farmers, Diffusion of Innovation, Risk factors, Agrochemicals, Occupational Exposure, Risk Factors, Risk Assessment, and Pharmacology and pharmaceutical sciences
Nanocellulose (NC) is emerging as a highly promising nanomaterial for a wide range of applications. Moreover, many types of NC are produced, each exhibiting a slightly different shape, size, and chemistry. The main objective of this study... more
Nanocellulose (NC) is emerging as a highly promising nanomaterial for a wide range of applications. Moreover, many types of NC are produced, each exhibiting a slightly different shape, size, and chemistry. The main objective of this study was to compare cytotoxic effects of cellulose nanocrystals (CNC) and nanofibrillated cellulose (NCF). The human lung epithelial cells (A549) were exposed for 24 h and 72 h to five different NC particles to determine how variations in properties contribute to cellular outcomes, including cytotoxicity, oxidative stress, and cytokine secretion. Our results showed that NCF were more toxic compared to CNC particles with respect to cytotoxicity and oxidative stress responses. However, exposure to CNC caused an inflammatory response with significantly elevated inflammatory cytokines/chemokines compared to NCF. Interestingly, cellulose staining indicated that CNC particles, but not NCF, were taken up by the cells. Furthermore, clustering analysis of the in...
Research Interests:
Personal exposure to fungal bioaerosols derived from contaminated building materials or agricultural commodities may induce or exacerbate a variety of adverse health effects. The genomic mechanisms that underlie pulmonary immune responses... more
Personal exposure to fungal bioaerosols derived from contaminated building materials or agricultural commodities may induce or exacerbate a variety of adverse health effects. The genomic mechanisms that underlie pulmonary immune responses to fungal bioaerosols have remained unclear. The impact of fungal viability on the pulmonary microRNA and messenger RNA profiles that regulate murine immune responses was evaluated following subchronic inhalation exposure to Aspergillus fumigatus conidia. Three groups of naïve B6C3F1/N mice were exposed via nose-only inhalation to A. fumigatus viable conidia, heat-inactivated conidia, or HEPA-filtered air twice a week for 13 weeks. Total RNA was isolated from whole lung 24 and 48 hours post final exposure and was further processed for gene expression and microRNA array analysis. The molecular network pathways between viable and heat-inactivated conidia groups were evaluated. Comparison of datasets revealed increased Il4, Il13, and Il33 expression i...
Research Interests:
Influenza antiviral drugs that use protein inhibitors can lose their efficacy as resistant strains emerge. As an alternative strategy, we investigated the use of small interfering RNA molecules (siRNAs) by characterizing three siRNAs... more
Influenza antiviral drugs that use protein inhibitors can lose their efficacy as resistant strains emerge. As an alternative strategy, we investigated the use of small interfering RNA molecules (siRNAs) by characterizing three siRNAs (M747, M776 and M832) targeting the influenza matrix 2 gene and three (NS570, NS595 and NS615) targeting the nonstructural protein 1 and 2 genes. We also re-examined two previously reported siRNAs, M331 and M950, which target the matrix 1 and 2 genes. Treatment with M331-, M776-, M832-, and M950-siRNAs attenuated influenza titer. M776-siRNA treated cells had 29.8% less infectious virus than cells treated with the previously characterized siRNA, M950. NS570-, NS595- and NS615-siRNAs reduced nonstructural protein 1 and 2 expression and enhanced type I interferon expression by 50%. Combination siRNA treatment attenuated 20.9% more infectious virus than single siRNA treatment. Our results suggest a potential use for these siRNAs as an effective anti-influen...
Research Interests:
Research Interests:
Research Interests: Immunology, Medicine, Quantitative analysis, Allergy, Humans, and 13 moreLaTeX, Health Care Workers, Proteins, Rubber, Biological markers, Quantitative Analysis, Food and Drug Administration, Antigen, Clinical Allergy and Immunology, Natural rubber latex, Protein content, Total protein, and Drug hypersensitivity
Antigenic protein levels in commercially available latex medical gloves were studied. For comparison, the gloves were divided into four main groups; powdered examination, powder-free examination, powdered surgical, and powder-free... more
Antigenic protein levels in commercially available latex medical gloves were studied. For comparison, the gloves were divided into four main groups; powdered examination, powder-free examination, powdered surgical, and powder-free surgical. Residual protein levels of 91 different glove brands were determined using the LEAP (latex ELISA for antigenic proteins) assay and found to be extremely variable. The possible sources of variability were investigated. Lot-to-lot variability was determined by testing multiple lots of five different brands of surgical gloves. The authors also determined glove-to-glove variability, variability within an individual glove, and test-method variability. It was observed that lot-to-lot variability (25-61% relative standard deviation--RSD) and glove-to-glove variability (51% RSD) were of similar magnitude and accounted for most of the variability found within a given brand of gloves. However, the greatest source of variability identified was brand-to-brand variability (143-283% RSD).
Research Interests:
Research Interests:
Research Interests:
Influenza virus infection induces several changes in host miRNA profile, host cell death and tissue damage. Cytochrome c is a regulator of the intrinsic apoptotic pathway and is altered during viral infections. Within the first 3h of... more
Influenza virus infection induces several changes in host miRNA profile, host cell death and tissue damage. Cytochrome c is a regulator of the intrinsic apoptotic pathway and is altered during viral infections. Within the first 3h of infection with influenza virus, significant down-regulation of hsa-miRNA-4276 (miRNA-4276) is followed by a 2-fold increase in cytochrome c oxidase VIC (COX6C) mRNA was found to occur in human alveolar and bronchial epithelial cells. Expression of caspase-9 also increased within the first 3h of infection, but subsequently decreased. Modulation of miR-4276 using mimic and inhibitor oligonucleotides showed significant down-regulation or up-regulation, respectively, of COX6C expression. Our data suggests that on initial exposure to influenza virus, host cells upregulate COX6C mRNA expression through silencing miR-4276 and repressed viral replication by inducing the apoptotic protein caspase-9. Taken together, these data suggest that miR-4276 may be an important regulator of the early stages of infection by influenza.
Research Interests:
Hev b 7 is a Hevea brasiliensis latex allergen with sequence identities of 39% to 42% to patatins recently identified as potato allergens. The complementary DNAs encoding 2 different Hev b 7 isoforms were previously reported. The aim of... more
Hev b 7 is a Hevea brasiliensis latex allergen with sequence identities of 39% to 42% to patatins recently identified as potato allergens. The complementary DNAs encoding 2 different Hev b 7 isoforms were previously reported. The aim of this study was to determine the sequence variation of Hev b 7 and to compare the IgE reactivity of individual isoforms in vitro and in vivo. A further objective was to evaluate possible cross-reactivities between Hev b 7 and patatins and proteins from banana and avocado. An H brasiliensis lambda ZAP complementary DNA (cDNA) library was screened with use of a Hev b 7 cDNA probe. Four Hev b 7 isoforms were produced in recombinant form and their IgE-binding capacities were compared. IgE immunoblot inhibitions and ELISA inhibition assays were used to investigate the possible cross-reactivity between Hev b 7 and recombinant potato patatin and proteins from avocado and banana. Two new isoforms, S2 and D2, were identified by sequencing 32 cDNA clones with full-length coding regions. All 4 recombinant isoforms displayed esterase activity and identical IgE-binding capacities. The new isoforms S2 and D2 were evaluated in skin prick tests and provoked responses equivalent to natural Hev b 7. No cross-reactivity was observed between Hev b 7 isoforms and potato patatin and proteins from avocado and banana. All 4 recombinant Hev b 7 isoforms have equivalent IgE-binding capacity and therefore represent suitable reagents for the development of in vitro and in vivo diagnostic tests. Hev b 7, patatins, and their homologs appear not to contribute to cross-reactivity in the latex-fruit syndrome.
Research Interests: Immunology, Humans, Lauraceae, Female, Male, and 15 moreAllergens, Immunoglobulin E, Middle Aged, Adult, Esterases, Diagnostic Test, Protein isoforms, Amino Acid Sequence, Base Sequence, Protein Binding, PLANT PROTEINS, Enzyme Linked Immunosorbent Assay, cDNA library, Immunoblotting, and Molecular Sequence Data
Research Interests:
The distribution of protein kinase C (PKC) isoforms and phorbol 12-myristate 13-acetate (PMA)-induced activation of PKC in human monocytes was investigated. Using Western blot analysis, PKC beta was found to be the most abundant isoform... more
The distribution of protein kinase C (PKC) isoforms and phorbol 12-myristate 13-acetate (PMA)-induced activation of PKC in human monocytes was investigated. Using Western blot analysis, PKC beta was found to be the most abundant isoform in monocytes. PKC beta was equally distributed in the cytosol and membrane. PKC-alpha was readily detectable and found predominantly in the cytosol. Little to no PKC-epsilon, gamma, delta, and zeta were observed. Following the treatment of monocytes with PMA, the physical translocation of PKC alpha from the cytosol to the membrane occurred over 60 min. PMA-induced translocation of PKC-beta was difficult to detect by Western blot. Fura-2 analysis demonstrated that PMA-induced PKC translocation was not accompanied by a net change in cytosolic calcium levels. Using histone as a substrate for PKC activity, an extremely rapid translocation of PKC-dependent histone phosphorylation (PKC-DHP) was induced by PMA. Cytosolic PKC-DHP activity decreased to undetectable levels within 8 min. In contrast, analysis of PKC-dependent endogenous substrate phosphorylation (PKC-DESP) showed a pattern with a time-course similar to that observed with Western blot. Thus, translocation of PKC-DESP but not PKC-DHP activity correlated with PKC-alpha as determined by Western blot. The data support the concept that PKC activity is substrate dependent and suggest that using one assay for the measurement of PKC activity may lead to erroneous conclusions.
Research Interests:
Research Interests:
In order to prepare for a possible influenza pandemic, a better understanding of the potential for airborne transmission of influenza from person to person is needed. The objective of this study was to directly compare the generation of... more
In order to prepare for a possible influenza pandemic, a better understanding of the potential for airborne transmission of influenza from person to person is needed. The objective of this study was to directly compare the generation of aerosol particles containing viable influenza virus during coughs and exhalations. Sixty-one adult volunteer outpatients with influenza-like symptoms were asked to cough and exhale three times into a spirometer. Aerosol particles produced during coughing and exhalation were collected into liquid media using aerosol samplers. The samples were tested for the presence of viable influenza virus using a viral replication assay (VRA). Fifty-three test subjects tested positive for influenza A virus. Of these, 28 (53%) produced aerosol particles containing viable influenza A virus during coughing, and 22 (42%) produced aerosols with viable virus during exhalation. Thirteen subjects had both cough aerosol and exhalation aerosol samples that contained viable v...
Research Interests:
Research Interests:
Epidemiological surveys indicate that occupants of mold contaminated environments are at increased risk of respiratory symptoms. The immunological mechanisms associated with these responses require further characterization. The aim of... more
Epidemiological surveys indicate that occupants of mold contaminated environments are at increased risk of respiratory symptoms. The immunological mechanisms associated with these responses require further characterization. The aim of this study was to characterize the immunotoxicological outcomes following repeated inhalation of dry Aspergillus fumigatus spores aerosolized at concentrations potentially encountered in contaminated indoor environments. A. fumigatus spores were delivered to the lungs of naïve BALB/cJ mice housed in a multi-animal nose-only chamber twice a week for a period of 13 weeks. Mice were evaluated at 24 and 48 hours post-exposure for histopathological changes in lung architecture, recruitment of specific immune cells to the airways, and serum antibody responses. Germinating A. fumigatus spores were observed in lungs along with persistent fungal debris in the perivascular regions of the lungs. Repeated exposures promoted pleocellular infiltration with concomita...
Research Interests:
Diisocyanates (dNCOs) are low molecular weight chemical sensitizers that react with autologous proteins to produce neoantigens. dNCO-haptenated proteins have been used as immunogens for generation of dNCO-specific antibodies and as... more
Diisocyanates (dNCOs) are low molecular weight chemical sensitizers that react with autologous proteins to produce neoantigens. dNCO-haptenated proteins have been used as immunogens for generation of dNCO-specific antibodies and as antigens to screen for dNCO-specific antibodies in exposed individuals. Detection of dNCO-specific antibodies in exposed individuals for diagnosis of dNCO asthma has been hampered by poor sensitivities of the assay methods in that specific IgE can only be detected in approximately 25% of the dNCO asthmatics. Apart from characterization of the conjugates used for these immunoassays, the choice of the carrier protein and the dNCO used are important parameters that can influence the detection of dNCO-specific antibodies. Human serum albumin (HSA) is the most common carrier protein used for detection of dNCO specific-IgE and -IgG but the immunogenicity and/or antigenicity of other proteins that may be modified by dNCO in vivo is not well documented. In the cu...
Purified plasma fibronectin (Fn) enhanced the secretory activity of rat peritoneal exudate macrophages as measured by 35S-methionine incorporation into protein released into culture supernatants. Enhancement of protein secretion was... more
Purified plasma fibronectin (Fn) enhanced the secretory activity of rat peritoneal exudate macrophages as measured by 35S-methionine incorporation into protein released into culture supernatants. Enhancement of protein secretion was dose-dependent and increased with time in culture. Addition of various concentrations of supernatant from cultures of macrophages with Fn resulted in a significant increase in thymocyte proliferation elicited by phytohaemagglutinin. The stimulatory activity of the supernatant was Fn dose-dependent and increased with increasing concentrations of macrophages. This thymocyte stimulatory effect was not due to the presence of Fn in the culture supernatant or to the minimal contamination with endotoxin detected in the Fn preparations. These data suggest that the inflammatory macrophage interaction with Fn results in the release of interleukin-1. They also are consistent with the reported ability of Fn to stimulate lymphocyte transformation.
Research Interests:
Research Interests:
Intercellular cell adhesion molecule-1 (ICAM-1) is an inducible cell surface glycoprotein that is expressed on many cell types. Influenza virus infection enhanced ICAM-1 expression and messenger RNA levels. Human bronchial epithelial... more
Intercellular cell adhesion molecule-1 (ICAM-1) is an inducible cell surface glycoprotein that is expressed on many cell types. Influenza virus infection enhanced ICAM-1 expression and messenger RNA levels. Human bronchial epithelial cells (HBEpC) and nasal epithelial cells, on exposure to different strains of influenza virus (H1N1, H3N2, and H9N1) showed significant increase in ICAM-1 gene expression (p&amp;amp;amp;amp;amp;amp;lt;0.001) along with the ICAM-1 protein levels (surface and secreted). Depleting ICAM-1 in HBEpC with ICAM-1 siRNA and subsequently infecting with H1N1 showed increased viral copy numbers. Influenza virus infection in HBEpC resulted in up-regulation of NF-ĸB protein and the lack of ICAM-1 decreased NF-ĸB activity in NF-ĸB luciferase reporter assay. Addition of exogenous IL-1β to HBEpC induced the ICAM-1 expression and decreased matrix gene copy number. Taken together, HBEpC induced ICAM-1 plays a key role in modulating the influenza virus survival possibly through the NF-ĸB pathway.
Research Interests:
ABSTRACT Traditionally, fungal identification has largely been based on the subjective micro- and macroscopic examination of morphological and culture characteristics. Matrix-assisted laser desorption/ionization time-of-flight mass... more
ABSTRACT Traditionally, fungal identification has largely been based on the subjective micro- and macroscopic examination of morphological and culture characteristics. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI TOF MS) was used to generate reproducible mass spectral “fingerprints” for 76 fungal species, particularly from the medically important genera, Penicillium and Aspergillus. The mass spectra contain abundant mass signals and allow unambiguous discrimination between species. Species identification error rates were determined to be 0% and 1.4% using resubstitution and cross-validation methods, respectively. The ability of MALDI TOF MS to differentiate fungal strains was additionally examined for the aflatoxin producing species, Aspergillus flavus. Identification error rates for 40 tested A. flavus cultures from five unique strains were determined to be 0% and 5% using resubstitution and cross-validation methods, respectively. Analysis of dematiaceous (dark-pigmented) fungi has been observed to yield poor MALDI-TOF mass spectra. Results demonstrate this was due to the presence of melanin in the cell wall of fungal spores and hyphae. Strategies to overcome this limitation are presented. These results indicate that MALDI-TOF MS data may be a useful diagnostic tool and alternative to available immunodiagnostic and molecular methods for the objective identification of environmental, industrial and clinically important fungal species.
Research Interests:
A latex-allergic patient presented with a severe local reaction to a non-latex wound closure bandage following surgery. Extracts of the bandage were analyzed by gas chromatograph-electron impact-mass spectrometry (GC EI-MS) in the total... more
A latex-allergic patient presented with a severe local reaction to a non-latex wound closure bandage following surgery. Extracts of the bandage were analyzed by gas chromatograph-electron impact-mass spectrometry (GC EI-MS) in the total ion monitoring mode. Components were identified by their ion mass fingerprint and elution time as a corresponding standard from the GC column. The chemicals identified were 4,4'-thiobis-(6-tert-butyl-m-cresol) (TBBC), 6-tert-Butyl-m-cresol (BC), 2,4-di-tert-butylphenol (BP) and erucamide (EA). Sensitization potential of these chemicals was evaluated using two quantitative structure-activity relationship (QSAR) programs. The phenol 2,6-di-tert-butyl-4-(hydroxymethyl)phenol (BHP) was also included in the test series. It was initially thought to be present in the bandage but detectable levels could not be confirmed. The potential for TBBC to induce a sensitization response was predicted by both Derek for Windows and TOPKAT 6.2. The potential for BC ...
Research Interests:
Research Interests:
To evaluate the effect of topical povidone iodine ointment on wound healing. 60 female mice randomly divided into four groups, A-D. Each mouse had a 2 cm linear incision made on the dorsal skin. Group A had povidone iodine ointment, and... more
To evaluate the effect of topical povidone iodine ointment on wound healing. 60 female mice randomly divided into four groups, A-D. Each mouse had a 2 cm linear incision made on the dorsal skin. Group A had povidone iodine ointment, and group B had ointment base applied for 7 days to the healing incision. Group C were given steroids for 7 days, and group D were allowed to heal without treatment. On Day 8, the strength of the incision was tested with an in vivo tensometer, and the hydroxyproline content of the incision was determined. Using ANOVA and Fischer's LSD test (P < 0.05), povidone iodine as well as steroid groups had significantly reduced wound strengths as compared to the controls and the group with ointment base. No significant difference in the hydroxyproline content was seen. Povidone iodine significantly reduces wound strength without reducing the total hydroxyproline content of the wound.
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) was used to generate highly reproducible mass spectral... more
Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) was used to generate highly reproducible mass spectral &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;fingerprints&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39; for twelve Penicillium species. Prior to MALDI-TOF MS analysis, eight replicate cultures of each Penicillium species were subjected to three one-minute bead-beating cycles in an acetonitrile/trifluoroacetic acid solvent. The mass spectra contained abundant peaks in the range of m/z 5000-20 000, and allowed unambiguous discrimination between species. In addition, a biomarker common to all Penicillium mass spectra was observed at m/z 13 900. Discriminant analysis using the MALDI-TOF MS data yielded classification error rates of 0% (i.e. 100% correct identification), indicating that MALDI-TOF MS data may be a useful diagnostic tool for the objective identification of Penicillium species of environmental and clinical importance.
Research Interests:
Research Interests:
Current screening methodologies for detecting infectious airborne influenza virus are limited and lack sensitivity. To increase the sensitivity for detecting infectious influenza virus in an aerosol sample, the viral replication assay was... more
Current screening methodologies for detecting infectious airborne influenza virus are limited and lack sensitivity. To increase the sensitivity for detecting infectious influenza virus in an aerosol sample, the viral replication assay was developed. With this assay, influenza virus is first amplified by replication in Madin-Darby canine kidney (MDCK) cells followed by detection with quantitative PCR (qPCR). Spanning a 20-h replication period, matrix gene expression levels from infectious virus were measured at several time points using qPCR and found to exponentially increase. Compared with the traditional culture-based viral plaque assay, the viral replication assay resulted in a 4.6 × 10(5) fold increase in influenza virus detection. Furthermore, viral replication assay results were obtained in half the time of the viral plaque assay. To demonstrate that the viral replication assay is capable of detecting airborne influenza virus, dilute preparations of strain A/WS/33 were loaded into a nebulizer, aerosolized within a calm-air settling chamber and subsequently collected using NIOSH Two-Stage Bioaerosol Samplers. At the most diluted concentration corresponding to a chicken embryo infectious dose 50% endpoint (CEID(50)) of 2.8E+02/ml, the viral replication assay was able to detect infectious influenza virus that was otherwise undetectable by viral plaque assay. The results obtained demonstrate that the viral replication assay is highly sensitive at detecting infectious influenza virus from aerosol samples.