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1.
Biomaterials ; 313: 122816, 2024 Sep 05.
Article in English | MEDLINE | ID: mdl-39250864

ABSTRACT

Pro-fibrotic M2-like macrophages are widely implicated in the pathogenesis and progression of lung fibrosis due to their production of pro-fibrotic growth factors and cytokines. Yeast beta-glucan (YBG) microparticles have shown potential as immunomodulators that can convert macrophage polarization from a pro-fibrotic phenotype to an anti-fibrotic phenotype through the engagement of the Dectin-1 receptor. However, the processing conditions used to fabricate YBG microparticles can lead to unpredictable immunomodulatory effects. Herein, we report the use of Pressurized Gas eXpanded liquids (PGX) Technology® to fabricate YBG (PGX-YBG) microparticles with higher surface areas, lower densities, and smaller and more uniform size distributions compared to commercially available spray-dried YBGs. PGX-YBG is shown to activate Dectin-1 more efficiently in vitro while avoiding significant TLR 2/4 activation. Furthermore, PGX-YBG microparticles effectively modulate M2-like fibrosis-inducing murine and human macrophages into fibrosis-suppressing macrophages both in vitro as well as in ex vivo precision-cut murine lung slices, suggesting their potential utility as a therapeutic for addressing a broad spectrum of fibrotic end-point lung diseases.

2.
Article in English | MEDLINE | ID: mdl-34486923

ABSTRACT

Over 200 million people in over 35 countries are affected by excessive fluoride in their waters. For people that do not have access to a centralized water treatment plant, there is a need for an on-site defluoridation system that requires no special operational expertise, does not use hazardous chemicals, and is sustainable by the local population. 8 different calcium phosphate precipitation systems were analyzed and tested for fluoride removal effectiveness. An effective system would have final fluoride concentrations less than 1.5 mg/L and final solutions with pH within drinkable limits. Phosphoric acid with the addition of a calcium carbonate source was found to have a 99.8% fluoride removal rate. Monosodium phosphate with addition of slaked lime was also found to be effective with a 99.98% fluoride removal rate. An optimal slaked lime to monosodium phosphate ratio that achieved effective fluoride removal and neutral pH was found. With 0.45 g of Ca(OH)2 and 1 g of NaH2PO4, initial fluoride concentrations up to 100 mg/L or more could be reduced to near zero concentrations, and a volume of approximately 337 mL of water with a concentration of 5 mg/L F- could to be reduced to less than 1.5 mg/L F-.


Subject(s)
Water Pollutants, Chemical , Water Purification , Calcium Carbonate , Calcium Phosphates , Fluorides , Humans , Phosphates , Water Pollutants, Chemical/analysis
3.
AIDS Behav ; 24(12): 3562-3573, 2020 Dec.
Article in English | MEDLINE | ID: mdl-32488554

ABSTRACT

Adherence to antiretroviral therapy (ART) is critical to achieving viral suppression. However, social determinants of health (SDoH) can undermine patient adherence to ART, resulting in drug resistance that compromises future treatment options. We assessed ART adherence and HIV-1 drug resistance at the national and state levels in the US and investigated their associations with SDoH and other HIV-related outcomes. Data were obtained from Symphony Health's Integrated Dataverse (IDV), Monogram/LabCorp Database, as well as national and publicly available databases, including Centers for Disease Control and Prevention (CDC), American Community Survey (ACS), and J. Kaiser Family Foundation (KFF). Inferential analyses were performed to investigate associations using patient-level data, and the results were reported by state and overall within the nation. Correlations between continuous variables were estimated by the Spearman's test, and that between continuous variable and categorical variable were estimated using one-way analysis of variance (ANOVA). State-level rates of poor adherence and resistance ranged from 26 to 55% and 20 to 54%, respectively. Female gender, non-white race, low education, poverty, and unemployment were associated with poor adherence; female gender was associated with drug resistance. Both adherence and resistance were correlated to HIV prevalence rates. Our findings suggest that US patients living with HIV face great challenges associated with poor ART adherence and HIV-1 drug resistance.


Subject(s)
HIV Infections , HIV-1 , Anti-HIV Agents/therapeutic use , Drug Resistance, Viral , Female , HIV Infections/drug therapy , HIV Infections/epidemiology , Humans , Medication Adherence , Social Determinants of Health
4.
Oncogene ; 30(13): 1518-30, 2011 Mar 31.
Article in English | MEDLINE | ID: mdl-21119603

ABSTRACT

The fibroblast growth factor 8b (FGF8b) oncogene is known to be primarily involved in the tumorigenesis and progression of hormone-related cancers. Its role in other epithelial cancers has not been investigated, except for esophageal cancer, in which FGF8b overexpression was mainly found in tumor biopsies of male patients. These observations were consistent with previous findings in these cancer types that the male sex-hormone androgen is responsible for FGF8b expression. Nasopharyngeal carcinoma (NPC) is a highly metastatic cancer of head and neck commonly found in Asia. It is etiologically associated with Epstein-Barr Virus (EBV) infection, inflammatory tumor microenvironment and relatively higher male predominance. Here, we reported for the first time that FGF8b is overexpressed in this EBV-associated non-hormone-related cancer of the head and neck, NPC. More importantly, overexpression of FGF8b mRNA and protein was detected in a large majority of NPC tumors from both male and female genders, in addition to multiple NPC cell lines. We hypothesized that FGF8b overexpression may contribute to NPC tumorigenesis. Using EBV-associated NPC cell lines, we demonstrated that specific knockdown of FGF8b by small interfering RNA inhibited cell proliferation, migration and invasion, whereas exogenous FGF8b stimulated these multiple phenotypes. Further mechanistic investigation revealed that in addition to NF-κB signaling (a major inflammatory signaling pathway known to be activated in NPC), an important EBV oncoprotein, the latent membrane protein 1 (LMP1), was found to be a direct inducer of FGF8b overexpression in NPC cells, whereas androgen (testosterone) has minimal effect on FGF8b expression in EBV-associated NPC cells. In summary, our study has identified LMP1 as the first viral oncogene capable of directly inducing FGF8b (an important cellular oncogene) expression in human cancer cells. This novel mechanism of viral-mediated FGF8 upregulation may implicate a new role of oncoviruses in human carcinogenesis.


Subject(s)
Fibroblast Growth Factor 8/physiology , Gene Expression Regulation, Neoplastic , Herpesvirus 4, Human/pathogenicity , Oncogenes , Carcinoma , Cell Movement , Cell Proliferation , Female , Fibroblast Growth Factor 8/antagonists & inhibitors , Fibroblast Growth Factor 8/genetics , Humans , Male , Mitogen-Activated Protein Kinases/metabolism , NF-kappa B/physiology , Nasopharyngeal Carcinoma , Nasopharyngeal Neoplasms/pathology , Nasopharyngeal Neoplasms/virology , Neoplasm Invasiveness , RNA, Messenger/analysis , RNA, Small Interfering/genetics , Viral Matrix Proteins/physiology
5.
Oncogene ; 30(9): 1127-34, 2011 Mar 03.
Article in English | MEDLINE | ID: mdl-21057531

ABSTRACT

c-Met represents an important emerging therapeutic target in cancer. In this study, we demonstrate the mechanism by which c-Met tyrosine kinase inhibition inhibits tumor growth in a highly invasive Asian-prevalent head and neck cancer, nasopharyngeal cancer (NPC). c-Met tyrosine kinase inhibitors (TKIs; AM7 and c-Met TKI tool compound SU11274) downregulated c-Met phosphorylation, resulting in marked inhibition of NPC cell growth and invasion. Strikingly, inhibition of c-Met resulted in significant downregulation of TP53-induced Glycolysis and Apoptosis Regulator (TIGAR) and subsequent depletion of intracellular NADPH. Importantly, overexpression of TIGAR ameliorated the effects of c-Met kinase inhibition, confirming the importance of TIGAR downregulation in the growth inhibitory activity of c-Met TKI. The effects of c-Met inhibition on TIGAR and NADPH levels were observed with two different c-Met TKIs (AM7 and SU11274) and with multiple cell lines. As NADPH provides a crucial reducing power required for cell survival and proliferation, our findings reveal a novel mechanistic action of c-Met TKI, which may represent a key effect of c-Met kinase inhibition. Our data provide the first evidence linking c-Met, TIGAR and NADPH regulation in human cancer cells suggesting that inhibition of a tyrosine kinase/TIGAR/NADPH cascade may have therapeutic applicability in human cancers.


Subject(s)
Indoles/pharmacology , Intracellular Signaling Peptides and Proteins/genetics , NADP/biosynthesis , Nasopharyngeal Neoplasms/metabolism , Piperazines/pharmacology , Protein Kinase Inhibitors/pharmacology , Proto-Oncogene Proteins c-met/antagonists & inhibitors , Pyrimidinones/pharmacology , Quinolines/pharmacology , Sulfonamides/pharmacology , Apoptosis , Apoptosis Regulatory Proteins , Cell Line, Tumor , Cell Proliferation/drug effects , Cell Survival , Down-Regulation , Humans , Nasopharyngeal Neoplasms/drug therapy , Nasopharyngeal Neoplasms/pathology , Phosphoric Monoester Hydrolases , Phosphorylation , Proto-Oncogene Proteins c-met/genetics , Proto-Oncogene Proteins c-met/metabolism , Signal Transduction/drug effects , Signal Transduction/genetics
6.
Anal Chem ; 81(1): 509-14, 2009 Jan 01.
Article in English | MEDLINE | ID: mdl-19035650

ABSTRACT

In the assembly of microarrays and microarray-based chemical assays and enzymatic bioassays, most approaches use pins for contact spotting. Acoustic dispensing is a technology capable of nanoliter transfers by using acoustic energy to eject liquid sample from an open source well. Although typically used for well plate transfers, when applied to microarraying, it avoids the drawbacks of undesired physical contact with the sample; difficulty in assembling multicomponent reactions on a chip by readdressing, a rigid mode of printing that lacks patterning capabilities; and time-consuming wash steps. We demonstrated the utility of acoustic dispensing by delivering human cathepsin L in a drop-on-drop fashion into individual 50-nanoliter, prespotted reaction volumes to activate enzyme reactions at targeted positions on a microarray. We generated variable-sized spots ranging from 200 to 750 microm (and higher) and handled the transfer of fluorescent bead suspensions with increasing source well concentrations of 0.1 to 10 x 10(8) beads/mL in a linear fashion. There are no tips that can clog, and liquid dispensing CVs are generally below 5%. This platform expands the toolbox for generating analytical arrays and meets needs associated with spatially addressed assembly of multicomponent microarrays on the nanoliter scale.


Subject(s)
Microarray Analysis/methods , Nanotechnology/methods , Acoustics/instrumentation , Cathepsin L , Cathepsins/chemistry , Cysteine Endopeptidases/chemistry , Fluorescent Dyes/chemistry , Glycerol/chemistry , Humans , Microarray Analysis/instrumentation , Nanoparticles/chemistry , Nanotechnology/instrumentation
7.
Occup Environ Med ; 66(3): 161-8, 2009 Mar.
Article in English | MEDLINE | ID: mdl-18805889

ABSTRACT

INTRODUCTION: To investigate possible associations between miscarriage and occupational exposures in the Shanghai textile industry. METHODS: A retrospective cohort study of miscarriages among 1752 women in the Shanghai textile industry was conducted. Reproductive history was self-reported by women and occupational work histories were collected from factory personnel records. Occupational exposures were assigned by linking work history information to an industry-specific job-exposure matrix informed by factory-specific textile process information and industrial hygiene assessments. Estimates of cotton dust and endotoxin exposure were also assigned. Odds ratios (OR) and 95% CI were estimated by multivariate logistic regression, with adjustment for age at pregnancy, educational level, smoking status of the woman and her spouse, use of alcohol, and woman's year of birth. RESULTS: An elevation in risk of a spontaneously aborted first pregnancy was associated with exposure to synthetic fibres (OR 1.89, 95% CI 1.20 to 3.00) and mixed synthetic and natural fibres (OR 3.31, 95% CI 1.30 to 8.42). No increased risks were observed for women working with solvents, nor were significant associations observed with quantitative cotton dust or endotoxin exposures. Associations were robust and similar when all pregnancies in a woman's reproductive history were considered. CONCLUSIONS: Occupational exposure to synthetic fibres may cause miscarriages, and this possibility should be the subject of further investigation.


Subject(s)
Abortion, Spontaneous/etiology , Air Pollutants, Occupational/toxicity , Dust , Occupational Diseases/etiology , Textile Industry , Abortion, Spontaneous/chemically induced , Adult , Aged , China , Cohort Studies , Cotton Fiber , Endotoxins/toxicity , Female , Humans , Middle Aged , Occupational Diseases/chemically induced , Occupational Exposure , Odds Ratio , Pregnancy , Risk Assessment/methods
8.
Anal Biochem ; 381(1): 101-6, 2008 Oct 01.
Article in English | MEDLINE | ID: mdl-18616925

ABSTRACT

Miniaturizing bioassays to the nanoliter scale for high-throughput screening reduces the consumption of reagents that are expensive or difficult to handle. Through the use of acoustic dispensing technology, nanodroplets containing 10 microM ATP (3 microCi/microL (32)P) and reaction buffer in 10% glycerol were positionally dispensed to the surface of glass slides to form 40-nL compartments (100 droplets/slide) for Pim1 (proviral integration site 1) kinase reactions. The reactions were activated by dispensing 4 nL of various levels of a pyridocarbazolo-cyclopentadienyl ruthenium complex Pim1 inhibitor, followed by dispensing 4 nL of a Pim1 kinase and peptide substrate solution to achieve final concentrations of 150 nM enzyme and 10 microM substrate. The microarray was incubated at 30 degrees C (97% R(h)) for 1.5 h. The spots were then blotted to phosphocellulose membranes to capture phosphorylated substrate. With phosphor imaging to quantify the washed membranes, the assay showed that, for doses of inhibitor from 0.75 to 3 microM, Pim1 was increasingly inhibited. Signal-to-background ratios were as high as 165, and average coefficients of variation for the assay were approximately 20%. Coefficients of variation for dispensing typical working buffers were under 5%. Thus, microarrays assembled by acoustic dispensing are promising as cost-effective tools that can be used in protein assay development.


Subject(s)
Acoustics , Nanotechnology/methods , Protein Array Analysis/methods , Fluorescent Dyes/metabolism , Fungal Proteins , Mitogen-Activated Protein Kinases/metabolism , Reproducibility of Results , Solutions
9.
Int Arch Occup Environ Health ; 79(3): 251-8, 2006 Mar.
Article in English | MEDLINE | ID: mdl-16220287

ABSTRACT

OBJECTIVES: Thyroid cancer risk has been previously associated with increased age at first pregnancy and history of miscarriage. Occupational risk factors for thyroid cancer, with the exception of radioactive iodine, have not been well investigated. We conducted a case-cohort study nested in a cohort of 267,400 female textile workers in Shanghai, China, who had been followed for cancer incidence during 1989-1998. METHODS: The analysis included 130 incident thyroid cases and 3,187 subcohort non-cases. Reproductive history was determined by questionnaire at baseline. Historical exposures were reconstructed from work history and information on factory processes and exposures. Cox proportional hazards analysis was performed to estimate hazard ratios (HR) for reproductive factors and occupational exposures. RESULTS: Associations were observed between thyroid cancer and employment in jobs with 10 or more years of benzene exposure (HR 6.43, 95% CI: 1.08, 38) and formaldehyde exposure (HR 8.33, 95% CI: 1.16, 60). Administration workers also had an increased risk (HR 1.56, 95% CI: 1.08, 2.25). No associations between examined reproductive factors and thyroid cancer were observed in this study. CONCLUSIONS: Despite statistically imprecise risk estimates, the findings suggest potential associations with some occupational chemical exposures in this cohort of textile workers.


Subject(s)
Air Pollutants, Occupational/adverse effects , Occupational Diseases/chemically induced , Occupational Exposure/adverse effects , Reproductive History , Textile Industry , Thyroid Neoplasms/chemically induced , Adult , Aged , Alcohol Drinking , China/epidemiology , Female , Humans , Marital Status , Middle Aged , Occupational Diseases/epidemiology , Risk Assessment , Smoking , Thyroid Neoplasms/epidemiology
10.
Neuroscience ; 137(1): 83-92, 2006.
Article in English | MEDLINE | ID: mdl-16289354

ABSTRACT

Neurons are added throughout life to the dentate gyrus of the hippocampus of the mammalian brain. Progenitors residing in the dentate gyrus progress through three distinct stages of adult neurogenesis: proliferation, survival and differentiation. One of the most potent factors which regulates adult neurogenesis is adrenal-derived glucocorticoids. Raised levels of glucocorticoids suppress progenitor division, while removal of glucocorticoids by adrenalectomy stimulates proliferation of these cells in the dentate gyrus. We have recently reported that both pre- and post-mitotic corticoid environments powerfully regulate survival of progenitor cells in a time-dependent manner. However, it is unknown if glucocorticoids alter the process of neuronal differentiation, since not all of the newly-formed cells acquire a neuronal fate during development. Here we employ triple immuno-fluorescence staining techniques to phenotype surviving progenitor cells 28 days after labeling. Results show that high levels of corticosterone (the major glucocorticoid in rodents) either before or after progenitor labeling discouraged the acquisition of neuronal fate. Similar to its effect on survival, post-mitotic corticosterone also regulates neuronal differentiation in a time-dependent fashion, but this action is most prominent from around 19-27 days after the cells were born. In contrast, a corticoid-free environment either before or after progenitor proliferation did not affect neuronal differentiation. Combining these data with previous survival data obtained from the same animals allowed us to estimate the total number of neurons formed resulting from different corticoid treatments. Raised corticosterone significantly reduced neuronal production while adrenalectomy resulted in significantly higher number of neurons in the adult male rat hippocampus.


Subject(s)
Cell Differentiation/physiology , Corticosterone/metabolism , Hippocampus/cytology , Neurons/cytology , Stem Cells/cytology , Animals , Fluorescent Antibody Technique , Hippocampus/metabolism , Male , Neurons/metabolism , Rats , Stem Cells/metabolism
11.
Neuroscience ; 123(4): 951-65, 2004.
Article in English | MEDLINE | ID: mdl-14751288

ABSTRACT

Axon guidance molecules and related proteins such as semaphorin 3A, neuropilin-1, plexin-1, netrin-1, growth-associated protein, olfactory marker protein, cypin and collapsin response mediator proteins guide the development of neural circuits in the olfactory bulb. In this study, transcriptions of these genes were examined in the olfactory bulb of female, male and neonatal testosterone propionate-treated female rats at the ages of 2, 5, 10, 15, 20, 25, 30 and 45 days. The semaphorin 3A, neuropilin-1, growth-associated protein and collapsin response mediator protein 1-5 genes were expressed significantly higher during the early development stages than in adulthood while the opposite is true for the olfactory marker protein. The expression profile of cypin and netrin-1 was relatively constant through development. A late effect of the neonatal testosterone propionate treatment on netrin-1, growth-associated protein, olfactory marker protein, collapsin response mediator proteins 1, 3, 4 and cypin gene expression was observed. The expression profiles of collapsin response mediator proteins and their related genes in the developing olfactory bulb confirmed most studies on the relationship between collapsin response mediator proteins and development in the brain. Sex differences of semaphorin 3A, neuropilin-1 as well as collapsin response mediator protein 3 at the early development stage and the late effect of neonatal testosterone propionate treatment on the expressions of netrin-1, growth-associated marker protein, cypin and collapsin response mediator proteins 1, 3 and 5 genes may indicate a possible role of these molecules on sexual differentiation of the olfactory bulb.


Subject(s)
Adaptor Proteins, Signal Transducing , Axons/metabolism , Gene Expression Regulation, Developmental/physiology , Olfactory Bulb/growth & development , Olfactory Bulb/metabolism , Sex Differentiation/physiology , Aging , Analysis of Variance , Animals , Bacterial Outer Membrane Proteins/genetics , Bacterial Outer Membrane Proteins/metabolism , Carrier Proteins/genetics , Carrier Proteins/metabolism , Cell Adhesion Molecules/genetics , Cell Adhesion Molecules/metabolism , Female , GAP-43 Protein/genetics , GAP-43 Protein/metabolism , Guanine Deaminase/genetics , Guanine Deaminase/metabolism , Intercellular Signaling Peptides and Proteins , Male , Nerve Growth Factors/genetics , Nerve Growth Factors/metabolism , Nerve Tissue Proteins/genetics , Nerve Tissue Proteins/metabolism , Netrin-1 , Neuropilin-1/genetics , Neuropilin-1/metabolism , Olfactory Marker Protein , Phosphoproteins/genetics , Phosphoproteins/metabolism , Pregnancy , RNA, Messenger/biosynthesis , Rats , Rats, Sprague-Dawley , Reverse Transcriptase Polymerase Chain Reaction/methods , Semaphorins/genetics , Semaphorins/metabolism , Tumor Suppressor Proteins
12.
Risk Anal ; 23(6): 1337-49, 2003 Dec.
Article in English | MEDLINE | ID: mdl-14641905

ABSTRACT

There is increasing interest in the integration of quantitative risk analysis with benefit-cost and cost-effectiveness methods to evaluate environmental health policy making and perform comparative analyses. However, the combined use of these methods has revealed deficiencies in the available methods, and the lack of useful analytical frameworks currently constrains the utility of comparative risk and policy analyses. A principal issue in integrating risk and economic analysis is the lack of common performance metrics, particularly when conducting comparative analyses of regulations with disparate health endpoints (e.g., cancer and noncancer effects or risk-benefit analysis) and quantitative estimation of cumulative risk, whether from exposure to single agents with multiple health impacts or from exposure to mixtures. We propose a general quantitative framework and examine assumptions required for performing analyses of health risks and policies. We review existing and proposed risk and health-impact metrics for evaluating policies designed to protect public health from environmental exposures, and identify their strengths and weaknesses with respect to their use in a general comparative risk and policy analysis framework. Case studies are presented to demonstrate applications of this framework with risk-benefit and air pollution risk analyses. Through this analysis, we hope to generate discussions regarding the data requirements, analytical approaches, and assumptions required for general models to be used in comparative risk and policy analysis.


Subject(s)
Environmental Health , Policy Making , Air Pollution/economics , Air Pollution/legislation & jurisprudence , Air Pollution/prevention & control , Animals , Cost-Benefit Analysis , Environmental Exposure , Environmental Health/economics , Environmental Health/legislation & jurisprudence , Fishes , Food Contamination , Humans , Public Policy , Risk Assessment , United States
13.
Biol Reprod ; 69(3): 746-51, 2003 Sep.
Article in English | MEDLINE | ID: mdl-12724276

ABSTRACT

Abnormal spermatogenesis in men with Y-chromosome microdeletions suggests that genes important for spermatogenesis have been removed from these individuals. VCY2 is a testis-specific gene that locates in the most frequently deleted azoospermia factor c region in the Y chromosome. We have raised an antiserum to VCY2 and used it to characterize the localization of VCY2 in human testis. Using Western blot analysis, the affinity-purified polyclonal VCY2 antibody gave a single specific band of approximately 14 kDa in size, corresponding to the expected size of VCY2 in all the collected human testicular biopsy specimens with normal spermatogenesis. Immunohistochemical analyses showed that VCY2 localized to the nuclei of spermatogonia, spermatocytes, and round spermatids, except elongated spermatids. At the ultrastructural level, VCY2 expression was found in the nucleus of human ejaculated spermatozoa. To determine the possible relationship of VCY2 with the pathogenesis of male infertility, we examined a group of infertile men with and without Y-chromosome microdeletions and with known testicular pathology using VCY2 antibody. VCY2 was weakly expressed at the spermatogonia and immunonegative in spermatocytes and round spermatids in testicular biopsy specimens with maturation arrest or hypospermatogenesis. The specific localization of the protein in germ cell nuclei indicates that VCY2 is likely to function in male germ cell development. The impaired expression of VCY2 in infertile men suggests its involvement in the pathogenesis of male infertility.


Subject(s)
Chromosome Deletion , Chromosomes, Human, Y/metabolism , Infertility, Male/genetics , Infertility, Male/metabolism , Proteins/metabolism , Spermatozoa/metabolism , Testis/metabolism , Adult , Biopsy , Blotting, Western , Cell Nucleus , Chromosomes, Human, Y/genetics , Chromosomes, Human, Y/ultrastructure , Humans , Immunohistochemistry , Infertility, Male/pathology , Male , Proteins/genetics , RNA, Messenger/analysis , Spermatogenesis/physiology , Spermatozoa/pathology , Spermatozoa/ultrastructure , Testis/pathology
14.
IEEE Trans Med Imaging ; 20(11): 1123-30, 2001 Nov.
Article in English | MEDLINE | ID: mdl-11700738

ABSTRACT

BACKGROUND: Although there have been recent advances in echocardiography, many studies remain suboptimal due to poor image quality and unclear blood-myocardium border. We developed a novel image processing technique, cardiac variability imaging (CVI), based on the variance of pixel intensity values during passage of ultrasound microbubble contrast into the left ventricle chamber, with the aim of enhancing endocardial border delineation and image quality. METHODS AND RESULTS: CVI analysis was performed on simulated data to test and verify the mechanism of image enhancement. Then CVI analysis was applied to echocardiographic images obtained in two different clinical studies, and still images were interpreted by expert reviewers. In the first study (N = 15), using contrast agent EchoGen, the number of observable wall segments in end-diastolic images, for example, was significantly increased by CVI (4.93) as compared to precontrast (3.28) and contrast images (3.36), P < 0.001 for both comparisons to CVI. In the second study (N = 8), using contrast agent Optison, interobserver variability of manually traced end-diastolic volumes was significantly decreased using CVI (22.3 ml) as compared to precontrast (63.4) and contrast images (49.0), P < 0.01 for both comparisons to CVI. CONCLUSION: CVI can substantially enhance endocardial border delineation and improve echocardiographic image quality and image interpretation.


Subject(s)
Echocardiography , Image Enhancement , Observer Variation , Algorithms , Endocardium/diagnostic imaging , Fourier Analysis , Heart Ventricles/diagnostic imaging , Humans , Models, Theoretical
15.
Clin Exp Ophthalmol ; 29(5): 330-4, 2001 Oct.
Article in English | MEDLINE | ID: mdl-11720162

ABSTRACT

The incidence of disseminated infection with Scedosporium species is increasing in patients with haematological malignancy. Two fatal cases are reported of patients with acute myeloid leukaemia and neutropenia who presented with Scedosporium endophthalmitis. Diagnosis of fungal infection was delayed as blood and vitreous cultures were positive only after 3 days in patient 1 and blood culture was positive at 7 days in patient 2. Despite antifungal therapy with amphotericin B and additional fluconazole in patient 2, both patients died of overwhelming fungal septicaemia. Post-mortem examination of the right globe in patient 1 showed haemorrhagic necrotizing chorioretinitis with numerous fungal hyphae in choroidal vessels, choroid, retina and vitreous. Scedosporium species are often resistant to conventional antifungal therapy including amphotericin B. Diagnosis is difficult and mortality in disseminated infection is high.


Subject(s)
Endophthalmitis/microbiology , Eye Infections, Fungal/microbiology , Mycetoma/microbiology , Scedosporium/isolation & purification , Acute Disease , Adult , Amphotericin B/therapeutic use , Antifungal Agents/therapeutic use , Endophthalmitis/diagnosis , Endophthalmitis/drug therapy , Eye Infections, Fungal/diagnosis , Eye Infections, Fungal/drug therapy , Fatal Outcome , Female , Fluconazole/therapeutic use , Fungemia/diagnosis , Fungemia/drug therapy , Fungemia/microbiology , Humans , Leukemia, Myeloid/microbiology , Male , Middle Aged , Mycetoma/diagnosis , Mycetoma/drug therapy , Neutropenia/microbiology
16.
J Am Coll Nutr ; 20(5 Suppl): 370S-380S; discussion 381S-383S, 2001 Oct.
Article in English | MEDLINE | ID: mdl-11603646

ABSTRACT

Despite significant achievements in treatment modalities and preventive measures, the prevalence of diabetes has risen exponentially in the last decade. Because of these limitations there is a continued need for new and more effective therapies. An increasing number of people are using dietary and herbal supplements, even though there is a general lack of evidence for their safety and efficacy. Consequently, science based medical and government regulators are calling for more randomized clinical studies to provide evidence of efficacy and safety. Our research group has selected two such promising and functionally complementary therapies for further investigation as potentially emerging alternative therapies for type 2 diabetes: Konjac-mannan (KJM) and American ginseng (AG). We have generated a mounting body of evidence to support the claim that rheologically-selected, highly-viscous KJM, and AG with a specific composition may be useful in improving diabetes control, reducing associated risk factors such as hyperlipidemia and hypertension, and ameliorating insulin resistance. KJM has a demonstrated ability to modulate the rate of absorption of nutrients from the small bowel, whereas AG has post-absorptive effects. Consequently, it appears that KJM and AG are acting through different, yet complementary, mechanisms: KJM by increasing insulin sensitivity and AG likely by enhancing insulin secretion. Before the therapeutic potential of KJM and AG as novel prandial agents for treatment of diabetes can be fully realized, further controlled trials with larger sample sizes and of longer duration are required. A determination of the active ingredients in AG, and the rheology-biology relationship of KJM are also warranted.


Subject(s)
Araceae , Diabetes Mellitus, Type 2/drug therapy , Mannans/therapeutic use , Panax/metabolism , Phytotherapy , Animals , Araceae/chemistry , Area Under Curve , Complementary Therapies , Diabetes Mellitus, Type 2/complications , Diabetes Mellitus, Type 2/metabolism , Dietary Supplements , Humans , Intestinal Absorption/drug effects , Mannans/pharmacology , Plant Roots/chemistry , Rheology , Safety , Treatment Outcome , Viscosity
17.
J Womens Health Gend Based Med ; 10(6): 541-50, 2001.
Article in English | MEDLINE | ID: mdl-11559451

ABSTRACT

Minority physicians provide care in a manner that promotes patient satisfaction and meets the needs of an increasingly diverse U.S. population. In addition, minority medical school faculty bring diverse perspectives to research and teach cross-cultural care. However, men and women of color remain underrepresented among medical school faculty, particularly in the higher ranks. National data show that although the numbers of women in medicine have increased, minority representation remains essentially static. Studying minority women faculty as a group may help to improve our understanding of barriers to diversification. Six National Centers of Excellence in Women's Health used a variety of approaches in addressing the needs of this group. Recommendations for other academic institutions include development of key diversity indicators with national benchmarks, creation of guidelines for mentoring and faculty development programs, and support for career development opportunities.


Subject(s)
Career Mobility , Faculty, Medical , Minority Groups , Physicians, Women/supply & distribution , Female , Guidelines as Topic , Humans , Male , United States , United States Dept. of Health and Human Services
18.
Sci Total Environ ; 274(1-3): 79-91, 2001 Jul 02.
Article in English | MEDLINE | ID: mdl-11453307

ABSTRACT

Analyses of competing risks are currently limited by the lack of empirically well-founded and generalizable quantitative methods. Specifically, quantitative methods for comparative risk analysis require the consideration of the population impacted, the duration of impact, the health endpoints at risk, and the impact on individual quality of life. Whereas risk analysis can be used to provide quantitative estimates of disease incidence, environmental health policy analyses do not often account for differences in health impact from alternative disease states. We discuss the methodological issues related to the use of quality adjusted life years (QALY) as a metric for normalizing expected disease incidence to account for health impact. Through a case study of the risks and benefits of fish consumption, we demonstrate the use of QALY weights with dose-response models for environmental health policy decision making. We suggest that, although this approach can be generalized for use in comparative risk and health policy analysis, it is informationally intensive and requires additional assumptions to those used in traditional safety/risk assessment.


Subject(s)
Environmental Health , Health Policy , Models, Biological , Quality-Adjusted Life Years , Adult , Age Distribution , Animals , Child , Dietary Proteins , Female , Fishes , Humans , Life Tables , Male , Models, Statistical , Mortality , Risk Assessment , Risk Factors
19.
J Biol Chem ; 276(13): 10423-31, 2001 Mar 30.
Article in English | MEDLINE | ID: mdl-11139571

ABSTRACT

In epithelial and endothelial cells, tight junctions regulate the paracellular permeability of ions and proteins. Disruption of tight junctions by inflammation is often associated with tissue edema, but regulatory mechanisms are not fully understood. Using ECV304 cells as a model system, lysophosphatidic acid and histamine were found to increase the paracellular permeability of the tracer horseradish peroxidase. Cytoskeletal changes induced by these agents included stimulation of stress fiber formation and myosin light chain phosphorylation. Additionally, occludin, a tight junction protein, was a target for signaling events triggered by lysophosphatidic acid and histamine, events that resulted in its phosphorylation. A dominant-negative mutant of RhoA, RhoA T19N, or a specific inhibitor of Rho-activated kinases, Y-27632, prevented stress fiber formation, myosin light chain phosphorylation, occludin phosphorylation, and the increase in tracer flux in response to lysophosphatidic acid. In contrast, although RhoA T19N and Y-27632 blocked the cytoskeletal events induced by histamine, they had no effect on the stimulation of occludin phosphorylation or increased tracer flux, indicating that occludin phosphorylation may regulate tight junction permeability independently of cytoskeletal events. Thus, occludin is a target for receptor-initiated signaling events regulating its phosphorylation, and this phosphorylation may be a key regulator of tight junction permeability.


Subject(s)
Membrane Proteins/metabolism , Tight Junctions/physiology , rhoA GTP-Binding Protein/metabolism , Actins/metabolism , Adenoviridae/genetics , Cell Line , Cytochalasin D/pharmacology , Cytoskeleton/metabolism , Dose-Response Relationship, Drug , Electrophoresis, Gel, Two-Dimensional , Gene Transfer Techniques , Genes, Dominant , Histamine/pharmacology , Horseradish Peroxidase/metabolism , Humans , Lysophospholipids/pharmacology , Microscopy, Fluorescence , Nucleic Acid Synthesis Inhibitors/pharmacology , Occludin , Permeability , Phosphorylation , Precipitin Tests , Signal Transduction , Stress Fibers/metabolism , Time Factors
20.
Physician Exec ; 27(6): 38-42, 2001.
Article in English | MEDLINE | ID: mdl-11769164

ABSTRACT

As we move into the 21st Century, the U.S. health care system faces tremendous challenges such as care for an aging and increasingly diverse population, escalating costs and limited resources. Government, consumers, hospitals and the insurance industry are positioning themselves for the future. Physicians need to do the same. Physicians must come to the table and assert leadership by working collaboratively with major stakeholders. Examine some steps that need to be taken to help shape the future of medicine.


Subject(s)
Health Care Reform/trends , Health Care Sector/trends , Leadership , Patient Satisfaction , Physician's Role , Aged , Cooperative Behavior , Cost Control/trends , Humans , Interinstitutional Relations , Managed Care Programs , Physician Executives , Population Dynamics , United States
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