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Spruance SL, Tyring SK, Smith MH, Meng TC. Application of a topical immune response modifier, resiquimod gel, to modify the recurrence rate of recurrent genital herpes: a pilot study. J Infect Dis 2001; 184:196-200. [PMID: 11424018 DOI: 10.1086/322007] [Citation(s) in RCA: 79] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2000] [Revised: 03/27/2001] [Indexed: 11/04/2022] Open
Abstract
Resiquimod (R-848), a topically active immune response modifier, induced production of interferon-alpha and interleukin-12 in cultured blood mononuclear cells and decreased genital herpes recurrences in an animal model. In this study, 52 patients with frequently recurrent genital herpes applied topical resiquimod gel 0.01% (twice or thrice weekly) or 0.05% (once or twice weekly) or vehicle gel to herpes lesions for 3 weeks. During the 6-month observation period after treatment, median days to first recurrence in the pooled resiquimod group was 169 days, compared with 57 days for the vehicle group (P=.0058). In all, 32% of resiquimod-treated patients completed the observation period without a recurrence, compared with 6% of vehicle-treated patients (P=.039). Resiquimod 0.05% twice weekly produced dose-limiting inflammation at the lesion sites, but the other regimens were well tolerated. Application of resiquimod to genital herpes lesions appeared to reduce the frequency of recurrences.
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Burger J, Gaines KF, Peles JD, Stephens WL, Boring CS, Brisbin IL, Snodgrass J, Bryan AL, Smith MH, Gochfeld M. Radiocesium in fish from the Savannah River and Steel Creek: potential food chain exposure to the public. RISK ANALYSIS : AN OFFICIAL PUBLICATION OF THE SOCIETY FOR RISK ANALYSIS 2001; 21:545-559. [PMID: 11572432 DOI: 10.1111/0272-4332.213131] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
This study examined radiocesium (137Cs) levels in fish from the vicinity of the Department of Energy's Savannah River Site (SRS), a former nuclear weapons production facility in South Carolina. Fish from the Savannah River were sampled above (upstream), along, and below (downstream) the SRS, and from Steel Creek, a tributary that runs through the SRS. There was some off-site contamination of 137Cs in the Savannah River watershed due to low-level releases from past nuclear production on the SRS. The null hypotheses tested were that there would be no differences in 137Cs levels as a function of location along the river, and between species collected from the river and from Steel Creek on the SRS. For six of eight species of fish collected from the Savannah River, there were no differences in 137Cs levels in muscle from fish collected above, along, or below the SRS; exceptions were bowfin and shellcracker. Fish collected from Steel Creek had significantly higher levels (by about an order of magnitude) of 137Cs in muscle tissue than fish collected in the Savannah River. However, no fish from either Steel Creek or the Savannah River had 137Cs levels above the European Economic Community limit for fresh meat of 0.6 Bq/g. Lifetime cancer risk was calculated using the cancer slope factor of 3.2 x 10(-11)/pCi, and various fish consumption scenarios reflecting actual data from Savannah River fishermen. Using mean 137Cs concentrations and median fish consumption for 70 years for Black males-the group with the highest consumption-the excess lifetime risk associated with the eight species of fish in the Savannah River ranged from 9.0 x 10(-7) to 1.0 x 10(-5). The same calculation for fish from Steel Creek gave risk estimates from 1.4 to 8.0 x 10(-5). The 95% level for consumption by Blacks, however, was about 70 kg/year. Black fishermen consuming that amount of bass from Steel Creek would sustain a lifetime risk of 3.1 x 10(-4), whereas the same consumption of Savannah River bass would yield a risk estimate of 1.5 x 10(-5).
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Jolley KW, Smith MH, Boden N, Henderson JR. Nature of the liquid crystalline phase transitions in the cesium pentadecafluorooctanoate (CsPFO)-water system: the nematic-to-isotropic transition. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2001; 63:051705. [PMID: 11414919 DOI: 10.1103/physreve.63.051705] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2000] [Indexed: 05/23/2023]
Abstract
Deuterium NMR spectroscopy of 2H2O has been used to monitor the magnetic-field-induced order on approaching a transition to a nematic phase in isotropic solutions of disklike micelles of cesium pentadecafluorooctanoate. Highly accurate data on the phase boundaries and spinodals have been obtained for solutions with volume fraction concentration straight phi between 0.078 and 0.201. The quantity TIN-T*, where T* is the spinodal limit of the isotropic phase and TIN is the temperature at which the nematic phase first appears on cooling, decreases linearly with decreasing concentration, extrapolating to zero only at zero concentration. Thus, there is no evidence to support the presence of a Landau point along the transition line as has previously been conjectured. The values for (TIN-T*)/TIN are in the range 10(-5)-10(-4), up to two orders of magnitude smaller than corresponding values reported for calamitic thermotropic nematics. The transition gap (phiNI-phiIN)/phiIN approximately 0.33% for phi<0.20 is also very small, although finite as required for a first-order phase transition. These data, when combined with previously measured properties, present an intriguing picture of the isotropic-to-nematic phase transition in a paradigmatic system of self-assembled diskotic particles. However, it is not completely clear, within the context of current theoretical understanding, whether the behavior of this system is explicable by hard-particle models, or if the self-assembly plays a crucial role in weakening the phase transition.
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Tang CM, Waterman LD, Smith MH, Thurston CF. The cel4 gene of Agaricus bisporus encodes a beta-mannanase. Appl Environ Microbiol 2001; 67:2298-303. [PMID: 11319115 PMCID: PMC92870 DOI: 10.1128/aem.67.5.2298-2303.2001] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2000] [Accepted: 03/03/2001] [Indexed: 11/20/2022] Open
Abstract
Mannases have industrial uses in food and pulp industries, and their regulation may influence development of the mushrooms of commercially important basidiomycetes. We expressed an Agaricus bisporus cel4 cDNA, which encodes a mannanase, in Saccharomyces cerevisiae and Pichia pastoris. CEL4 had no detectable activity on cellulose or xylan. This gene is the first isolated from this economically important fungus to encode a mannanase. P. pastoris secreted about three times more CEL4 than S. cerevisiae. The removal of the cellulose-binding domain of CEL4 lowered the secreted specific activity by P. pastoris by approximately 97%. The genomic sequence of cel4 was isolated by screening a cosmid library of A. bisporus C54-carb8. The open reading frame was interrupted by 12 introns. The level of extracellular CEL4 increases dramatically at the postharvest stage in compost extracts of A. bisporus fruiting cultures. In laboratory liquid cultures of A. bisporus, the activity of CEL4 detected in the culture filtrate reached a maximum after 21 days. The levels of CEL4 broadly mirrored the levels of enzyme activity. In the Solka floc-bound mycelium, CEL4 protein showed a maximum after 2 to 3 weeks of culture and then declined. Changes in CEL4 activity during fruiting-body development suggest that hemicellulose utilization plays an important role in sporophore formation. The availability of the cloned gene will further studies of compost decomposition and the extracellular enzymes that fungi deploy in this process.
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Abstract
A measure of range of ability is used to profile the 85-years-old-and-older (oldest old) population, including the highly disabled institutional population. This new measure uses two new questions available in the 1990 Decennial Census concerning a self-care limitation and a mobility limitation as well as the usual question concerning a work limitation. In addition to examining the extent of disability among the oldest old, the article examines the extent of care potentially available in the household as well as the economic characteristics of this age group. It is also profiled in terms of relevant personal characteristics, including age, gender, marital status, race, ethnicity, rural residence, education, and employment. A key question addressed is the need for help or care among the oldest old and how various long-term care proposals would meet such needs. A careful analysis of this unique and growing population is necessary to both allay fears of the cost of care or help as well as to dispel stereotypes of this age group as frail and dependent, and in need of institutional care.
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Smith MH, Anderson RT, Bradham DD, Longino CF. Rural and urban differences in mortality among Americans 55 years and older: analysis of the National Longitudinal Mortality Study. J Rural Health 2001; 11:274-85. [PMID: 10153687 DOI: 10.1111/j.1748-0361.1995.tb00425.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Previous research on rural and urban differences in risk of mortality has been inconclusive. This article used data from the National Longitudinal Mortality Study to establish whether all-cause mortality risk among persons 55 years and older varies by degree of urbanization, controlling for the potential sociodemographic confounders of age, gender, race/ethnicity, education, income, and marital status. Using the Cox Proportional Hazards Regression Procedure, the authors found that persons living in the most rural locales and those living in rural communities in standard metropolitan statistical areas (SMSAs) have the lowest risk of mortality, while those living in SMSA central cities had the highest risk of dying during the study period. The protective effect of rural residence declines in older age cohorts.
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Earle JR, Smith MH, Harris CT, Longino CF. Women, marital status, and symptoms of depression in a midlife national sample. J Women Aging 2001; 10:41-57. [PMID: 9870051 DOI: 10.1300/j074v10n01_04] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Previous studies of the correlates of depression among women have not generally been based on adequate midlife samples or precision in the specification of marital status categories. The present analysis is designed to address these deficiencies and is based on data from the Health and Retirement Survey-Wave 1 (i.e., respondents 51 to 61 years old). Results indicate that married women are less likely to report symptoms of depression than their unmarried counterparts. The mental health benefits of marriage are greater for men than for women. Moreover, other variables, such as marital satisfaction, self-rated health, and employment status are more powerful predictors of emotional well-being in midlife than marital status per se. The quality of marriage affects depressive symptoms more strongly for women than men.
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Abstract
Clinical faculty have a legal, ethical, and professional obligation to evaluate students' clinical performance to ensure safe practitioners. However, many clinical faculty members fear litigation and hesitate to give an unsatisfactory grade to students who do not meet established standards. If the decision to assign a failing clinical grade was "careful and deliberate" and the student was afforded due process, the principle of judicial deference emerges to protect the clinical instructor and the educational institution.
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Peles JD, Bryan AL, Garten CT, Ribble DO, Smith MH. Ecological half-life of 137Cs in fish from a stream contaminated by nuclear reactor effluents. THE SCIENCE OF THE TOTAL ENVIRONMENT 2000; 263:255-262. [PMID: 11194159 DOI: 10.1016/s0048-9697(00)00713-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Radiocesium (137Cs) concentrations were determined during 1974, 1981 and 1998 for seven species of fish inhabiting a stream (Steel Creek) contaminated by effluents from a nuclear reactor to examine the decline of this radionuclide in a natural ecosystem. Median 137Cs concentrations were highest in Micropterus salmoides (largemouth bass) during each year of the investigation (1974 = 6.67 Bq g(-1) dry wt. of whole body; 1981 = 3.72 Bq g(-1); 1998 = 0.35 Bq g(-1)), but no patterns of differences were observed among Aphredoderus sayanus (pirate perch), Esox americanus (redfin pickerel), Lepomis auritus (redbreast sunfish), L. gulosus (warmouth), L. punctatus (spotted sunfish), and Notropis cummingsae (dusky shiner). Results demonstrated a rapid decline in 137Cs within fish from Steel Creek during the 24-year period. For example, 137Cs concentrations in all fish species declined significantly among years, even after accounting for radioactive decay. The observed percent declines in 137Cs concentrations of individual species were 3-4 times greater between 1974 and 1981 compared to that expected by physical decay alone, and 2-3 times greater during 1981-1998. Ecological half-lives (EHLs) of 137Cs in fish ranged from 4.43 years in A. sayanus to 6.53 years in L. gulosus. The EHL for 137Cs in all fish species combined was 5.54 years. Current levels of 137Cs in fish from Steel Creek (1.16 Bq g(-1) dry wt. of whole body to below detection limits) indicate that the consumption of fish from this ecosystem poses little risk to humans and sensitive wildlife species. These results demonstrate the importance of incorporating the concept of ecological half-life into determinations concerning the length and severity of potential risks associated with radiocontaminants.
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Smith MH, Altman DG, Strunk B. Readiness to change: newspaper coverage of tobacco farming and diversification. HEALTH EDUCATION & BEHAVIOR 2000; 27:708-24. [PMID: 11104371 DOI: 10.1177/109019810002700607] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Diversification, like tobacco use prevention and cessation, is an important public health concern. The multilevel patterns of tobacco dependency suggest the need for public health approaches to the "tobacco problem." To understand how newspaper and wire service journalists cover issues involving diversification among tobacco farmers, the authors performed a content analysis of a subset of 100 articles on diversification and tobacco farming. Prochaska and DiClemente's stages of change model was applied to the "problem behavior" of tobacco farming. Among news accounts relating to tobacco farmers or tobacco farming, print media accounts gave relatively little attention to the issue of diversification. Farmers in the sample of news accounts were generally cognizant of pressures to diversify away from reliance on tobacco cultivation but were frustrated due to obstacles to diversification such as limited diversification options and relative absence of infrastructure supports. Community leaders and policy-relevant sources generally supported diversification.
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Denninghoff KR, Smith MH. Optical model of the blood in large retinal vessels. JOURNAL OF BIOMEDICAL OPTICS 2000; 5:371-374. [PMID: 11092424 DOI: 10.1117/1.1289144] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/1999] [Revised: 05/17/2000] [Accepted: 06/14/2000] [Indexed: 05/23/2023]
Abstract
Several optical techniques that investigate blood contained within the retinal vessels are available or under development. We present a mechanical model that simulates the optical properties of the eye, the retinal vessels, and the ocular fundus. A micropipette is chosen as the retinal vessel model, and a mechanical housing is constructed to simulate the eyeball. Spectralon is used to simulate the retinal layers. Filling the eye with fluid index matched to the glass pipette eliminates reflection and refraction effects from the pipette. An apparatus is constructed and used to set the oxygen, nitrogen, and carbon dioxide concentrations in whole human blood. These whole blood samples are pumped through the pipette at 34 microL/min. Measurements made in the model eye closely resemble measurements made in the human eye. This apparatus is useful for developing the science and testing the systems that optically investigate blood and blood flow in the large retinal vessels.
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Vasilakos JP, Smith RM, Gibson SJ, Lindh JM, Pederson LK, Reiter MJ, Smith MH, Tomai MA. Adjuvant activities of immune response modifier R-848: comparison with CpG ODN. Cell Immunol 2000; 204:64-74. [PMID: 11006019 DOI: 10.1006/cimm.2000.1689] [Citation(s) in RCA: 126] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
R-848 and imiquimod belong to a class of immune response modifiers that are potent inducers of cytokines, including IFN-alpha, TNF-alpha, IL-12, and IFN-gamma. Many of these cytokines can affect the acquired immune response. This study examines the effects of R-848 on aspects of acquired immunity, including immunoglobulin secretion, in vivo cytokine production, and Ag-specific T cell cytokine production. Results are compared with those of Th1 CpG ODN. R-848 and CpG ODN are effective at skewing immunity in the presence of Alum toward a Th1 Ab response (IgG2a) and away from a Th2 Ab response (IgE). R-848 and CpG ODN are also capable of initiating an immune response in the absence of additional adjuvant by specifically enhancing IgG2a levels. Both R-848 and imiquimod showed activity when given subcutaneously or orally, indicating that the compound mechanism was not through generation of a depot effect. Although CpG ODN behaves similarly to R-848, CpG ODN has a distinct cytokine profile, is more effective than R-848 when given with Alum in the priming dose, and is active only when given by the same route as the Ag. The mechanism of R-848's adjuvant activity is linked to cytokine production, where increases in IgG2a levels are associated with IFN-alpha, TNF-alpha, IL-12, and IFN-gamma induction, and decreases in IgE levels are associated with IFN-alpha and TNF-alpha. Imiquimod also enhances IgG2a production when given with Ag. The above results suggest that the imidazoquinolines R-848 and imiquimod may be attractive compounds for use as vaccine adjuvants and in inhibiting pathological responses mediated by Th2 cytokines.
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Smith MH, Wagenknecht LE, Legault C, Goff DC, Stump DA, Troost BT, Rogers AT. Age and other risk factors for neuropsychologic decline in patients undergoing coronary artery bypass graft surgery. J Cardiothorac Vasc Anesth 2000; 14:428-32. [PMID: 10972610 DOI: 10.1053/jcan.2000.7941] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
OBJECTIVE To evaluate if increasing age is a major determinant of long-term neuropsychologic (NP) dysfunction in patients undergoing coronary artery bypass graft (CABG) surgery. DESIGN Prospective cohort study. SETTING A single university hospital. PARTICIPANTS Three hundred eighty-one patients undergoing elective CABG surgery. INTERVENTIONS Baseline preoperative and intraoperative characteristics were assessed for all patients. A comprehensive NP test battery was conducted preoperatively and at 1 month postoperatively. MEASUREMENTS AND MAIN RESULTS Of the initial 381 patients, 319 (84%) returned for the 1-month visit. The overall incidence of an NP deficit was 21.6%. There was no significant difference seen with increasing age, although a trend was observed with highest NP deficit rate in the older than 65 age group. Other preoperative risk factors, including gender, education level, and preexisting diseases, were nonsignificant. Intraoperative variables were evaluated and revealed no significant differences across the age groups. CONCLUSIONS This cohort study did not find an increased incidence of NP deficits in elderly patients after CABG surgery. It has addressed the limitations of other studies, however, with (1) a comprehensive NP test battery, (2) longer-term follow-up, and (3) adequate sample size.
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Arany I, Tyring SK, Brysk MM, Stanley MA, Tomai MA, Miller RL, Smith MH, McDermott DJ, Slade HB. Correlation between pretreatment levels of interferon response genes and clinical responses to an immune response modifier (Imiquimod) in genital warts. Antimicrob Agents Chemother 2000; 44:1869-73. [PMID: 10858346 PMCID: PMC89977 DOI: 10.1128/aac.44.7.1869-1873.2000] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Imiquimod (IQ) has been successfully used in treatment of genital warts. In clinical settings, patients responded well but wart reduction rates varied. Our aim was to find a correlation between clinical responses and pretreatment (constitutive) levels of genes that might be involved in the molecular action of IQ. Since IQ is a cytokine inducer, we analyzed levels of expression of genes of the JAK/STAT signaling pathway and their inhibitors as well as interferon response factors (IRFs) in pretreatment biopsy specimens from complete responders (99 to 100% wart reduction rate) versus incomplete responders (75 to 92% wart reduction rate) by reverse transcription-PCR. We found that mRNA levels of signal transducer and activator of transcription 1 (STAT1) and IRF1 were higher in complete responders than in incomplete responders. Incomplete responders expressed larger amounts of STAT3, IRF2, and protein inhibitor of activated STAT1 (PIAS1) mRNAs compared to complete responders before IQ treatment. We hypothesize that high-level expression of STAT1 and IRF1 is advantageous for a better IQ response. The observed differences in constitutive mRNA levels of these genes may be the consequence of alterations in cellular differentiation and/or variable expression of endogenous interferons. Previous in vitro studies showed that keratinocyte differentiation coordinates the balance between positive and negative signals along the JAK/STAT pathway by regulating the IRF1:IRF2 and STAT1:PIAS1 ratios and thus affecting induction of IQ-inducible genes. Specifically, differentiation supports constitutive expression of STAT1 and IRF1 mRNAs but not expression of IRF2 and PIAS1. Our data are in good agreement with studies that showed the importance of STAT1 in cytokine induction and activation of interferon-responsive genes by IQ.
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Uhrínová S, Smith MH, Jameson GB, Uhrín D, Sawyer L, Barlow PN. Structural changes accompanying pH-induced dissociation of the beta-lactoglobulin dimer. Biochemistry 2000; 39:3565-74. [PMID: 10736155 DOI: 10.1021/bi992629o] [Citation(s) in RCA: 196] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
We have used NMR spectroscopy to determine the three-dimensional (3D) structure, and to characterize the backbone dynamics, of a recombinant version of bovine beta-lactoglobulin (variant A) at pH 2. 6, where the protein is a monomer. The structure of this low-pH form of beta-lactoglobulin is very similar to that of a subunit within the dimer at pH 6.2. The root-mean-square deviation from the pH 6.2 (crystal) structure, calculated for backbone atoms of residues 6-160, is approximately 1.3 A. Differences arise from the orientation, with respect to the calyx, of the A-B and C-D loops, and of the flanking three-turn alpha-helix. The hydrophobic cavity within the calyx is retained at low pH. The E-F loop (residues 85-90), which moves to occlude the opening of the cavity over the pH range 7.2-6.2, is in the "closed" position at pH 2.6, and the side chain of Glu89 is buried. We also carried out measurements of (15)N T(1)s and T(2)s and (1)H-(15)N heteronuclear NOEs at pH 2.6 and 37 degrees C. Although the residues of the E-F loop (residues 86-89) have the highest crystallographic B-factors, the conformation of this loop is reasonably well defined by the NMR data, and its backbone is not especially mobile on the pico- to nanosecond time scale. Several residues (Ser21, Lys60, Ala67, Leu87, and Glu112) exhibit large ratios of T(1) to T(2), consistent with conformational exchange on a micro- to millisecond time scale. The positions of these residues in the 3D structure of beta-lactoglobulin are consistent with a role in modulating access to the hydrophobic cavity.
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Smith MH, Denninghoff KR, Lompado A, Hillman LW. Effect of multiple light paths on retinal vessel oximetry. APPLIED OPTICS 2000; 39:1183-93. [PMID: 18338002 DOI: 10.1364/ao.39.001183] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Techniques for noninvasively measuring the oxygen saturation of blood in retinal arteries and veins are reported in the literature, but none have been sufficiently accurate and reliable for clinical use. Addressing the need for increased accuracy, we present a series of oximetric equations that explicitly consider the effects of backscattering by red blood cells and lateral diffusion of light in the ocular fundus. The equations are derived for the specific geometry of a scanning-beam retinal vessel oximeter; however, the results should also be applicable to photographic oximeters. We present in vitro and in vivo data that suggest the validity of these equations.
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Pfaff-McDonough SJ, Horne SM, Giddings CW, Ebert JO, Doetkott C, Smith MH, Nolan LK. Complement resistance-related traits among Escherichia coli isolates from apparently healthy birds and birds with colibacillosis. Avian Dis 2000; 44:23-33. [PMID: 10737641] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
In this study, 294 Escherichia coli isolates from birds with colibacillosis were collected from disease outbreaks throughout the United States and were compared with 75 fecal E. coli isolates of apparently healthy chickens by their possession of several purported virulence genes, resistance to rough-lipopolysaccharide-specific bacteriophages (rLPSr), and elaboration of capsule. Traits were selected for study on the basis of their association with complement resistance. The genes targeted in this study included those encoding colicin V (cvaC) and the outer membrane proteins TraT (traT), OmpA (ompA), and Iss (iss). No significant differences were found between the two groups of isolates in the occurrence of cvaC-, traT-, or ompA-homologous sequences or in rLPSr. Only a few isolates were encapsulated, and the isolates of healthy birds were significantly more likely to be encapsulated than were the isolates of sick birds. However, iss, whether detected through hybridization or amplification, was found in more of the disease-associated isolates than in those of healthy birds. This difference was highly significant. Further, iss sequences were widely distributed among isolates of different serotypes from various avian host species and sites within these hosts. Such results suggest that possession of the iss sequence by an avian E. coli isolate may be a good indicator of that isolate's potential to cause disease. This association warrants further study because iss and the protein it encodes may be useful targets of future colibacillosis control efforts.
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Abstract
Diabetic retinopathy is progressive, and detection early is essential for the prevention of blindness. Doppler flowmetry, retinal photography, scanning laser ophthalmoscopy, and retinal oximetry measurements may identify proliferative disease early. Drawbacks of these methods include lack of compliance, failure to refer, and failure to identify disease early. As a result, diabetic retinopathy is a leading cause of blindness. Our retinal oximeter measures the blood oxygen saturation in the large vessels of the retina near the optic disc. Retinal vessel oxygen saturations measured with our instrument are sensitive indicators of blood loss and hypoxia in swine. We are generating scientific data that suggests that retinal vessel oxygen saturations may be used to identify retinal hypoxia prior to changes in retinal vessel architecture. We expect to study humans within the next two years, and a clinically useful eye oximeter should be available in the near future.
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Gilson RJ, Shupack JL, Friedman-Kien AE, Conant MA, Weber JN, Nayagam AT, Swann RV, Pietig DC, Smith MH, Owens ML. A randomized, controlled, safety study using imiquimod for the topical treatment of anogenital warts in HIV-infected patients. Imiquimod Study Group. AIDS 1999; 13:2397-404. [PMID: 10597781 DOI: 10.1097/00002030-199912030-00011] [Citation(s) in RCA: 67] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE To assess the safety of imiquimod, an immune response modifier, in the topical treatment of external anogenital warts in HIV-infected patients. SETTING Clinical sites in the United Kingdom (eight) and the United States (five). DESIGN A prospective, randomized, double-blind, vehicle-controlled study of imiquimod 5% cream or vehicle applied for 8+/-2 h three times per week for a maximum of 16 weeks in HIV-seropositive males (n = 97) and females (n = 3) aged 18 years or more with clinically diagnosed external anogenital warts, CD4 T lymphocyte count of > or = 100 x 10(6) cells/l and Karnofsky score > or = 70. MAIN OUTCOME MEASURES Safety was assessed through the incidence and severity of local skin reactions and other adverse events, and through clinical laboratory tests. Wart clearance was documented by two-dimensional measurements of warts and by photography. RESULTS Among the patients treated with imiquimod (n = 65) and vehicle (n = 35), the most common local skin reaction was erythema, (41.9 and 26.7%, respectively) and the incidence of patients reporting at least one adverse event was 69.2 and 65.7%, respectively. No clinically meaningful differences or changes in laboratory values were observed between treatment groups, nor were drug-related adverse effects observed in regard to HIV disease. While there was no significant difference between treatment groups in the number of patients who totally cleared their baseline warts (imiquimod 11% versus vehicle 6%, P = 0.488), more imiquimod-treated patients experienced a > or = 50% reduction in baseline wart area (38% versus 14%, P = 0.013). CONCLUSION Most local skin reactions were mild and no adverse effects on HIV disease were observed. Topically applied imiquimod 5% cream reduced wart area and may have clinical utility in treating external anogenital warts in some HIV-infected patients.
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Langley PC, Richwald GA, Smith MH. Modeling the impact of treatment options in genital warts: patient-applied versus physician-administered therapies. Clin Ther 1999; 21:2143-55. [PMID: 10645759 DOI: 10.1016/s0149-2918(00)87244-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
With the availability of new patient-applied treatments for genital and perianal warts, medical providers, physician groups, and health systems are reassessing the role of physician-administered therapies. Two key questions are: how cost-effective are physician- versus patient-administered therapies and, given patient preferences for the convenience and privacy associated with the latter therapies, which of the 2 presently available treatments-imiquimod and podofilox-is most appropriate? The purpose of this article is to examine, from the perspective of the health care purchaser, these questions and to undertake a pharmacoeconomic analysis of the direct cost-effectiveness of therapy options, given targets being set for the outcomes of genital warts therapy. The analysis employs a synthetic, decision-modeling framework in which data on sustained clearance and the direct costs of treatment are drawn from both clinical studies and previous studies on the resources used to support treatment. Once targets are set-and it is proposed here that physicians should aim for at least a 50% sustained clearance rate for genital warts--it becomes clear that in cost per sustained clearance terms, imiquimod, as first-line therapy, is the most cost-effective intervention. If we compare imiquimod with podofilox as first-line therapy (with cryotherapy as the second-line option), the cost per sustained clearance for the imiquimod treatment sequence is $1367 compared with the podofilox-initiated sequence of $1508.
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Arany I, Tyring SK, Stanley MA, Tomai MA, Miller RL, Smith MH, McDermott DJ, Slade HB. Enhancement of the innate and cellular immune response in patients with genital warts treated with topical imiquimod cream 5%. Antiviral Res 1999; 43:55-63. [PMID: 10480263 DOI: 10.1016/s0166-3542(99)00033-9] [Citation(s) in RCA: 92] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The mechanism of action of imiquimod 5% cream applied topically to patients with genital warts was evaluated in a double-blind, placebo-controlled study. Imiquimod (16 patients) or placebo (three patients) was applied three times per week for up to 16 weeks. All imiquimod-treated patients had a > or =75% reduction in total wart area while only one of three placebo-treated patients had a similar reduction. Wart biopsies were taken at prestudy, week 6, and end of treatment. Polymerase chain reaction (PCR) for human papillomavirus (HPV) DNA and reverse transcriptase (RT)-PCR for messenger (m)RNAs were used to identify cytokines, cellular markers, viral gene products, and cell cycle markers in these biopsies. Treatment with imiquimod, an immune response modifier, stimulated significant increases in mRNA for interferon (IFN)-alpha, IFN-gamma and 2',5' oligoadenylate synthetase (2',5'-AS) as well as a tendency towards increases in tumor necrosis factor (TNF)-alpha and interleukin-12 p40. Significant increases in mRNA for CD4 and a trend toward increases in CD8 were also observed in imiquimod-treated patients, suggesting activation of a cell mediated immune response. Imiquimod administration was also associated with a significant decrease in viral load as measured by HPV DNA and L1 mRNA. The effects on HPV markers were accompanied by an apparent decrease in mRNA expression for markers of cell proliferation and an increase in mRNA for markers of keratinocyte differentiation and tumor suppressors.
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Altman DG, Strunk B, Smith MH. Newspaper and wire service coverage of tobacco farmers. HEALTH EDUCATION RESEARCH 1999; 14:131-7. [PMID: 10537942 DOI: 10.1093/her/14.1.131] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
This study examined print media coverage of tobacco farmers from the perspective of agenda setting, or the extent to which information is available to the public and perceived as important. A content analysis of 743 articles published between January 1, 1995 and June 30, 1997 was completed. The number of articles increased from 1995 to 1997. Of the topics analyzed, articles on tobacco settlement (7.1% of total) and diversification (15.6% of total) were the least prevalent. Because the settlement discussions did not occur until 1997 (when it comprised 26.4% of the total in the first 6 months), diversification was consistently the least covered topic. The two most frequent topics covered were tobacco companies (36.2%) and the tobacco price support program (32.3%). Except for one 6 month interval, there were substantially more articles in local/regional publications than in national publications. Public health professionals have called for tobacco farmers to diversify to non-tobacco enterprises. Yet, there is little discussion of diversification in print media. Without more attention to diversification, the public and policy makers will be ill-informed about opportunities and obstacles in this regard.
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Langley PC, Tyring SK, Smith MH. The cost effectiveness of patient-applied versus provider-administered intervention strategies for the treatment of external genital warts. THE AMERICAN JOURNAL OF MANAGED CARE 1999; 5:69-77. [PMID: 10345969] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
Abstract
OBJECTIVE External genital warts are one of the fastest growing sexually transmitted diseases in the United States today. Two forms of therapy are available: provider-administered and patient-applied. In the most widely used provider-administered ablative therapies, sustained clearance rates range from 18.5% to 40.1%. With nonablative, patient-applied therapies, which are typically more acceptable to patients, sustained clearance rates range from 19.6% with podofilox gel to 44.0% with imiquimod cream. The purpose of this study, given the range of therapies available, their cost differences, and clinical trial-reported differences in rates of sustained clearance, is to determine which therapy modalities, from the providers' perspective, are the most cost effective and which are likely to be the most acceptable to the patient population. STUDY DESIGN We consider the cost effectiveness of the two patient-applied therapies as first-line therapy followed by provider-administered ablative treatment as second-line therapy. A decision-analytic model framework is developed, with data drawn both from clinical trials and from previously published studies. RESULTS When considering a two-stage therapy model, with an average sustained clearance rate of 30% assumed for provider-administered ablative therapies, estimated costs per sustained cleared patient are $1265 for patients initially treated with imiquimod and $1304 for patients initially treated with podofilox gel. CONCLUSIONS Initial treatment with imiquimod is the preferred intervention option as it yields a 39% greater sustained clearance rate than podofilox gel while being 3% less costly per successful outcome.
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Smith MH. Optimum wavelength combinations for retinal vessel oximetry. APPLIED OPTICS 1999; 38:258-67. [PMID: 18305612 DOI: 10.1364/ao.38.000258] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Several investigators have demonstrated techniques for noninvasive measurement of the oxygen saturation of blood in retinal arteries and veins. These techniques have been based on measuring the optical density of a retinal vessel at multiple wavelengths and on calculating the oxygen saturation on the basis of the known absorption coefficients of hemoglobin and oxyhemoglobin. A technique is presented for determining the optimum wavelengths for retinal oximetry measurements. What is believed to be a novel wavelength combination of 488, 635, and 905 nm is found to provide excellent oxygen sensitivity across a broad range of typical vessel diameters and saturations. The use of this wavelength combination should allow for the most accurate retinal saturation measurements made to date.
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Smith MH, Nuara AA, Egen JG, Sirjani DB, Lam KS, Grimes WJ. Baculoviral expressed HLA class I heavy chains used to screen a synthetic peptide library for allele-specific peptide binding motifs. Mol Immunol 1998; 35:1033-43. [PMID: 10068038 DOI: 10.1016/s0161-5890(98)00096-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Recombinant baculoviruses encoding truncated HLA-A*0101 and HLA-A*0201 class I heavy chains have been isolated and used to infect lepidopteran cells. Proteins overexpressed in this system were glycosylated, and consisted of 282 amino acid residues after signal sequence cleavage. These class I heavy chains could fold into their native conformation in the presence of recombinant human beta2-microglobulin expressed in Escherichia coli and a synthetic peptide library of nonamers bound to resin-support beads. Reconstitution into native ternary complexes was detected using a conformation specific monoclonal antibody followed by isolation and sequencing of the bound peptides. The motifs obtained for HLA-A1.1 and HLA-A2.1 peptides are similar although more extensive than those derived from sequencing endogenous peptides. This approach selects peptides which form very stable complexes regardless of whether these peptides are generated under physiological conditions, thereby providing unique supplementary data for predicting and designing CTL epitopes. This method is based solely on peptide binding to the class I molecule and is therefore independent of any constraints imposed by endogenous intracellular processing or transport systems. A comparison of the two motifs provides an opportunity to distinguish between the requirements of binding from those arising as a function of intracellular processing or transport. Our findings are not consistent with a recent report suggesting that constraints on the COOH termini of these peptides can be attributed to the effects of either intracellular processing or transport. We find that the carboxy termini in the class I peptides analyzed to date mimic the endogenous data, suggesting that residues in this position contribute to binding affinity.
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