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Schoenfeld ER, Greene JM, Wu SY, Leske MC. Patterns of adherence to diabetes vision care guidelines: baseline findings from the Diabetic Retinopathy Awareness Program. Ophthalmology 2001; 108:563-71. [PMID: 11237912 DOI: 10.1016/s0161-6420(00)00600-x] [Citation(s) in RCA: 184] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
Abstract
OBJECTIVES (1) To describe baseline patterns of adherence to American Diabetes Association and American Academy of Ophthalmology vision care guidelines for diabetes in the Diabetic Retinopathy Awareness Program, and (2) to evaluate factors associated with nonadherence. This paper describes the baseline characteristics of a population enrolled in a prospective, randomized clinical trial. DESIGN Cross-sectional study. PARTICIPANTS Between October 1993 and May 1994, the study identified 2308 persons with diabetes, 18 years of age or older, who were residents of Suffolk County, New York, via a multimedia community-wide recruitment campaign. INTERVENTION AND METHODS Eligibility for the trial was determined during a 20-minute phone interview, which included questions about vision care practices; diabetes management; and knowledge, attitudes, and beliefs about diabetes, vision, and diabetic retinopathy. This paper describes these patient characteristics at baseline. Eligible patients would be randomized subsequently to a 2-year diabetes educational intervention arm, which included mailed packets and newsletters focused on vision care, or to a control nonintervention arm. MAIN OUTCOME MEASURE Nonadherence to guidelines at baseline was defined as the absence of a dilated eye examination during the year before recruitment into the study. RESULTS Of the 2308 persons interviewed, 813 (35%) did not follow the vision care guidelines; two thirds of this group reported no eye examination in the year before the interview, and one third had an undilated examination. Ophthalmologists performed 49% of the examinations in the nonadherent group, versus 86% in the adherent group. In logistic regression analyses, factors related to nonadherence were: younger age (odds ratio [OR] = 0.97), type 2 diabetes with or without insulin use (OR = 1.62 and 1.99, respectively), shorter diabetes duration (OR = 0.97), last eye examination performed by an optometrist (OR = 5.32) or other nonophthalmologist (OR = 4.29), less practical knowledge about diabetes (OR = 1.57), and no prior formal diabetes education (OR = 1.30). CONCLUSIONS Within this population, more than one third of participants had not been following vision care guidelines. Nonadherence was linked to several potentially modifiable factors; changes in these factors could enhance the early detection of diabetic retinopathy.
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Wu SY, Nemesure B, Leske MC. Observed versus indirect estimates of incidence of open-angle glaucoma. Am J Epidemiol 2001; 153:184-7. [PMID: 11159164 DOI: 10.1093/aje/153.2.184] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Incidence data on open-angle glaucoma (OAG) are limited and difficult to obtain. To date, few studies have reported incidence directly measured from population-based cohorts. Other reported estimates have been derived indirectly from age-specific prevalence by using several assumptions, and their validity is unknown. To the authors' knowledge, this report presents the first comparison of observed versus indirect estimates of OAG incidence based on data from the population-based Barbados Incidence Study of Eye Diseases (1992-1997) (n = 3,427; 85% participation). The observed 4-year incidence of OAG was 1.2% (95% confidence interval (CI): 0.6, 2.1%) at ages 40-49 years, 1.5% (95% CI: 0.8, 2.5%) at ages 50-59 years, 3.2% (95% CI: 2.0, 4.8%) at ages 60-69 years, and 4.2% (95% CI: 2.6, 6.3%) in persons at ages 70 or more years. When incidence was calculated from the prevalence data, power function fitting achieved a closer approximation to observed incidence than did logistic curve fitting. Calculated incidence rates for each group were similar when assuming mortality that was equal (incidence rate = 0.7, 1.3, 2.3, and 4.8%) or differential (incidence rate = 0.7, 1.2, 2.4, and 4.8%). Other nonlogistic approaches also increased the resemblance of observed and calculated estimates. In the absence of longitudinal data, reasonably valid incidence estimates of OAG were obtained from available prevalence data. These estimation techniques can be useful when OAG incidence estimates are required for research or public health purposes.
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Yeh SS, Wu SY, Levine DM, Parker TS, Olson JS, Stevens MR, Schuster MW. The correlation of cytokine levels with body weight after megestrol acetate treatment in geriatric patients. J Gerontol A Biol Sci Med Sci 2001; 56:M48-54. [PMID: 11193233 DOI: 10.1093/gerona/56.1.m48] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
BACKGROUND Cachexia is associated with elevated levels of cytokines in cancer and human immunodeficiency virus patients. Studies in cancer and acquired immunodeficiency syndrome patients showed that treatment with megestrol acetate (MA) is associated with improvement in appetite and weight gain. Reduction in the levels of cytokines is associated with weight gain in laboratory animals with cancer. This study evaluates the correlation between changes in cytokine (or their receptor) levels and weight following MA treatment in geriatric weight-loss patients. METHODS Veterans Administration Medical Center nursing home patients (N = 69) with a weight loss of > or =5% of usual body weight over the past 3 months or body weight 20% below their ideal body weight participated in a 12-week, randomized, double-blind, placebo-controlled trial, with an additional 13-week follow-up period. Patients were randomly assigned to receive a placebo or MA oral suspension of 800 mg/d for 12 weeks. Levels of the following cytokines (or their receptors) were measured at baseline and after 12 weeks of treatment: tumor necrosis factor soluble receptor (TNFR) subunits. TNFR-p55 and TNFR-p75: interleukin 6 (IL-6); and the soluble interleukin-2 receptor (sIL-2R). The subjects' weight and body composition were measured at the start of the study. Weight and mortality were followed up for another 13 weeks after discontinuing the MA study drug. RESULTS Elevated levels of IL-6 in almost all geriatric cachexic patients, compared with normal volunteers (mean, <4.6 pg/ml). were noted at baseline. At 12 weeks after the study drug treatment, there was a decrease in cytokine levels (or their receptors) in the MA group (mean change in IL-6, 3.63+/-6.62 pg/ml; TNFR-p55, -0.06+/-0.11 ng/ml; TNFR-p75. -0.01+/-0.29 ng/ml; and sIL-2R, 0.08+/-0.07 ng/ml) and the placebo group (mean change in IL-6, -2.08+/-3.92 pg/ml; TNFR-p55, -0.02+/-0.08 ng/ml; TNFR-p75, -0.20+/-0.18 ng/ml; and sIL-2R, 0.02+/-0.03 ng/ml). Although the change in cytokine levels was not statistically significant between the two groups, significant negative correlation (p < .05) was found. For example, increased weight correlated with decreased sIL-2R levels (r = .36) and TNFR-p75 (r = -.31; fat-free mass (FFM) gain and reduction of sIL-2R (r = -.39), TNFR-p75 (r = -.30). There was a significant correlation between weight gain and reduction of TNFR-p75 (r = .54), TNFR-p55 (r- = .47), and sIL-2R (r = -.53); FFM gain and reduction of sIL-2R (r = -.59), TNFR-p75 (r = -.41), TNFR-p55 (r = -.42); and fat gain and reduction of TNFR-p75 (r = -.41) in the MA group (p < .05), but not in the placebo group. CONCLUSIONS Although there was no significant change in cytokine levels between the two groups, the reduction in cytokine levels after MA treatment correlated with improvement in weight, fat mass, and FFM at 12 weeks.
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Leske MC, Connell AM, Wu SY, Nemesure B, Li X, Schachat A, Hennis A. Incidence of open-angle glaucoma: the Barbados Eye Studies. The Barbados Eye Studies Group. ARCHIVES OF OPHTHALMOLOGY (CHICAGO, ILL. : 1960) 2001; 119:89-95. [PMID: 11146731] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
OBJECTIVE To measure the 4-year risk of open-angle glaucoma (OAG) in a black population. DESIGN Population-based cohort study with 4 years of follow-up. SETTING Simple random sample of residents of Barbados, West Indies, aged 40 years or older. PARTICIPANTS A total of 3427 members of the cohort (85% of those eligible). MAIN OUTCOME MEASURE Development of glaucoma visual field defects and optic disc damage, confirmed by automated perimetry, independent fundus photographic gradings, and standardized ophthalmologic examinations. RESULTS The 4-year risk of OAG in black participants was 2.2% (95% confidence interval, 1.7%-2.8%), based on 67 newly developed cases of OAG. Incidence rates increased from 1.2% at ages 40 to 49 years to 4.2% at ages of 70 years or more, tending to be higher in men than women (2.7% vs 1.9%). About half of the incident cases were undiagnosed previously, and the rest were receiving OAG treatment. Of the 67 new cases of OAG, 32 had intraocular pressure of 21 mm Hg or less at baseline (1.2% incidence) and 35 had higher pressures (9% incidence). Risk was highest among persons classified as having suspect OAG at baseline (26.1%), followed by those with ocular hypertension (4.9%) and lowest in the remaining population (0.8%). CONCLUSIONS This longitudinal study provides new information on OAG risk, as well as the first incidence measurement in a black population. Although intraocular pressure increased risk, about half of the new cases had baseline pressures of 21 mm Hg or less. Results substantiate the high OAG risk in the population of African origin, especially in older adults; the relative role of intraocular pressure; and the considerable underdetection of new disease after 4 years of follow-up.
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Wu SY, Huang WS, Fisher DA, Florsheim WH, St Germain DL, Galton VA. Iodothyronine sulfotransferase activity in rat uterus during gestation. Pediatr Res 2000; 48:847-51. [PMID: 11102557 DOI: 10.1203/00006450-200012000-00024] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
In developing mammals, we and others demonstrated that sulfation is an important pathway in the metabolism of thyroid hormone, and there is significant fetal-maternal transfer of sulfated iodothyronine. In the present study, we characterized a novel iodothyronine sulfotransferase (IST) in pregnant rat uterus. (125)I-labeled 3,3'-diiodothyronine (T(2)), T(3), rT(3), and T(4) were used as substrates with unlabeled 3'-phosphoadenosine-5'-phosphosulfate (PAPS) as the sulfate donor. Sulfated iodothyronine products were separated by Sephadex LH-20 column and further identified on reverse phase HPLC. We measured IST activity in pregnant rat uterus by incubating 1 microM substrate, 50 microM PAPS, and 50 microg cytosol protein, pH 7.2, 30 min at 37 degrees C. The results show that the substrate preference of the uterine IST activity is: T(2 )> rT(3 )> T(3)> T(4); the pH optimum is 6.0 for T(2). The K(m) and V:(max) (for gestational day 21 uterus) for T(2) are 0.62 microM and 3466 pmol/mg protein/h, respectively; for PAPS the values are 2.6 microM and 1523 pmol/mg protein/h, respectively. During pregnancy, the total activities exhibit a U-shaped curve with minimum activity at day 13 of gestation; while a thermostable activity increases significantly near term. In summary, there is significant uterine IST that varies during pregnancy. The role of this uterine sulfotransferase activities in regulating the bioavailability of thyroid hormone in the developing fetus remains to be elucidated.
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Schoenfeld ER, Greene JM, Wu SY, O'Leary E, Forte F, Leske MC. Recruiting participants for community-based research: the Diabetic Retinopathy Awareness Program. Ann Epidemiol 2000; 10:432-40. [PMID: 11023622 DOI: 10.1016/s1047-2797(00)00067-3] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
PURPOSE Recruiting participants is a major challenge for population studies. We present the recruitment methods followed by the Diabetic Retinopathy Awareness Program (DRAP), a community-based, randomized, masked, controlled trial to meet and exceed its sample size goals. METHODS A county-wide multi-media promotional campaign to recruit and enroll participants in the trial was planned and executed from October 1993 through April 1994, with the assistance of the local news media and community and professional groups. A toll-free 800 number recruitment line was established, and postage-paid recruitment postcards distributed. The trial was designed to examine whether a mailed educational intervention could increase compliance with vision care guidelines among persons with diabetes in the community. RESULTS A total of 2308 persons with diabetes were interviewed for eligibility and 813 enrolled in the intervention trial, exceeding the original recruitment goals of 1800 and 600, respectively. Those who completed the enrollment interview reflected county demographics. During recruitment, newspaper, television and radio stories featured the study; pharmacies and physician offices displayed study materials; public service announcements appeared in local print and broadcast media. The largest single recruitment response was a local television news report, followed by a newspaper story. CONCLUSIONS These experiences substantiate the need for a comprehensive coordinated approach, using planned multiple sources, to achieve recruitment success. By engaging the lay and professional communities along with the media, recruitment costs can be kept to a minimum. Participant costs can be minimized by employing a toll-free number and eliminating study participant travel, thus allowing for inclusion of traditionally underserved populations. This approach is applicable to other studies, where community-based participation is desired.
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Pan WH, Chen JW, Fann C, Jou YS, Wu SY. Linkage analysis with candidate genes: the Taiwan young-onset hypertension genetic study. Hum Genet 2000; 107:210-5. [PMID: 11071381 DOI: 10.1007/s004390000365] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A genetic linkage study of young-onset hypertension was performed on data from 59 nucleus families of Han Chinese residing in Taiwan. Thirty seven microsatellite markers near 18 hypertension candidate genes were genotyped. In a nonparametric identity-by-descent sibpair analysis, a positive linkage signal (defined as P<0.05) was found for four microsatellite markers, viz., D1S1612 (P=0.0162), D1S547 (P=0.0263), D8S 1145 (P= 0.0284), and D17S2193 (P=0.0256), which were located near genes for atrial natriuretic peptide (NPPA)/glucose transporter 5 (SLC2A5), angiotensinogen (AGT), lipoprotein lipase (LPL), and angiotensin-conveting enzyme (DCP1), respectively. Marker D5S1480 located near beta-2-adrenergic receptor (ADRB2) had a borderline P value (P=0.0785) for the positive signal. Comprehensive genotyping with further markers in these regions is underway to confirm whether these genes are linked to young-onset hypertension.
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Abstract
Hepatitis delta virus (HDV) is unique relative to all known animal viruses, especially in terms of its ability to redirect host RNA polymerase(s) to transcribe its 1,679-nucleotide (nt) circular RNA genome. During replication there accumulates not only more molecules of the genome but also its exact complement, the antigenome. In addition, there are relatively smaller amounts of an 800-nt RNA of antigenomic polarity that is polyadenylated and considered to act as mRNA for translation of the single and essential HDV protein, the delta antigen. Characterization of this mRNA could provide insights into the in vivo mechanism of HDV RNA-directed RNA transcription and processing. Previously, we showed that the 5' end of this RNA was located in the majority of species, at nt 1630. The present studies show that (i) at least some of this RNA, as extracted from the liver of an HDV-infected woodchuck, behaved as if it contained a 5'-cap structure; (ii) in the infected liver there were additional polyadenylated antigenomic HDV RNA species with 5' ends located at least 202 nt and even 335 nt beyond the nt 1630 site, (iii) the 5' end at nt 1630 was not detected in transfected cells, following DNA-directed HDV RNA transcription, in the absence of genome replication, and (iv) nevertheless, using in vitro transcription with purified human RNA polymerase II holoenzyme and genomic RNA template, we did not detect initiation of template-dependent RNA synthesis; we observed only low levels of 3'-end addition to the template. These new findings support the interpretation that the 5' end detected at nt 1630 during HDV replication represents a specific site for the initiation of an RNA-directed RNA synthesis, which is then modified by capping.
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Leske MC, Wu SY, Nemesure B, Li X, Hennis A, Connell AM. Incidence and progression of lens opacities in the Barbados Eye Studies. Ophthalmology 2000; 107:1267-73. [PMID: 10889096 DOI: 10.1016/s0161-6420(00)00155-x] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
OBJECTIVE To provide 4-year cumulative incidence and progression rates of age-related lens opacities in a population > or =40 years of age, which is mainly of African origin. DESIGN Cohort study that reexamined surviving members of the population-based Barbados Eye Study 4 years after baseline. PARTICIPANTS Three thousand four hundred twenty-seven members of the Barbados Eye Study cohort (85% of those eligible). MAIN OUTCOME MEASURES The Lens Opacities Classification System II (LOCS II) was used at the slit lamp. Cumulative incidence was defined as the development of any nuclear, cortical or posterior subcapsular (PSC) opacities (LOCS II scores > or =2) among persons without that opacity type at baseline. Cumulative progression was defined by at least two-step increases in scores among persons with preexisting lens opacities. RESULTS The incidence of cortical opacities was about five times greater in black than white participants (age-gender adjusted relative risk = 4.7; 95% confidence interval: 1.9-11.4). In the black population, the 4-year incidence rates were 22.2% (20.4%-24.0%) for any cortical, 9.2% (8.2%-10.4%) for any nuclear, and 3.3% (2.7%-4.0%) for any PSC opacities; rates increased greatly with age. Four-year progression rates were 12.5% for cortical, 3.6% for nuclear, and 23.0% for PSC opacities, without consistent pattern by age. Women had a greater risk of cortical and nuclear opacities (P<0.05) than men and greater progression of nuclear opacities. The presence of PSC opacities at baseline seemed to at least double the incidence and progression rates of other opacities. In persons initially opacity free, single cortical opacities were the predominant type to develop at followup. Visual acuity loss frequently accompanied incident opacities. CONCLUSIONS This longitudinal study provides new population-based data on the natural history of lens opacities. Incidence and progression of opacities, especially of cortical opacities, were high. After 4 years of followup, 1 in 4 to 5 participants developed cortical opacities, 1 in 11 developed nuclear opacities, and 1 in 30 developed PSC opacities. The information obtained attests to the public health impact of age-related cataract, as well as its extent, in this and similar black populations.
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Liu L, Jayanthi CS, Tang M, Wu SY, Tombler TW, Zhou C, Alexseyev L, Kong J, Dai H. Controllable reversibility of an sp(2) to sp(3) transition of a single wall nanotube under the manipulation of an AFM tip: A nanoscale electromechanical switch? PHYSICAL REVIEW LETTERS 2000; 84:4950-4953. [PMID: 10990839 DOI: 10.1103/physrevlett.84.4950] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/28/1999] [Indexed: 05/23/2023]
Abstract
A simulation of the deflection of a single wall nanotube under the manipulation of an atomic force microscope tip revealed the key feature characterizing the deformation at relatively small bending angles to be a reversible transition from sp(2) to sp(3) bonding configurations in the bending region, leading to a 2 orders of magnitude reduction in conductance consistent with our most recent experimental observation. A local analysis elucidating the underlying physics of the findings is also discussed.
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Yeh SS, Wu SY, Lee TP, Olson JS, Stevens MR, Dixon T, Porcelli RJ, Schuster MW. Improvement in quality-of-life measures and stimulation of weight gain after treatment with megestrol acetate oral suspension in geriatric cachexia: results of a double-blind, placebo-controlled study. J Am Geriatr Soc 2000; 48:485-92. [PMID: 10811540 DOI: 10.1111/j.1532-5415.2000.tb04993.x] [Citation(s) in RCA: 109] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
BACKGROUND Weight loss among older patients is a severe problem, associated with an increased incidence of infections, decubiti, and death. Megestrol acetate (MA) causes weight gain in cachectic cancer and AIDS patients, but its effects in older cachectic patients are unknown. OBJECTIVE To compare the effects of MA oral suspension (O.S.), 800 mg/day, versus placebo on weight in geriatric nursing home patients with weight loss or low body weight. DESIGN Twelve-week, randomized, double-blind, placebo-controlled trial with a 13-week follow-up period. SETTING Veterans Administration Medical Center (VMAC) nursing home. PATIENTS Nursing home patients with weight loss of > or =5% of usual body weight over the past 3 months, or body weight 20% below their ideal body weight. INTERVENTIONS Patients were randomly assigned to receive placebo or MA 800 mg/day for 12 weeks and were then followed for 13 weeks off treatment. MEASUREMENTS Primary outcome was measured by weight and appetite change. Secondary outcome measures included sense of well-being, enjoyment of life, change in depression scale, laboratory nutrition parameters, energy intake counts, body composition, and adverse events. RESULTS At 12 weeks there were no significant differences in weight gain between treatment groups, whereas MA-treated patients reported significantly greater improvement in appetite, enjoyment of life, and well-being. Body composition was not statistically different between the two groups. At Week 25 (3 months after treatment), 61.9% of MA-treated patients had gained > or =1.82 kg (4 lbs) compared to 21.7% of placebo patients. CONCLUSIONS In geriatric patients with weight loss or low body weight MA improves appetite and well-being after 12 weeks of treatment. During the 3 months of MA treatment, there was no statistically significant weight gain (> or =4 lbs). Three months after treatment, weight gain (> or =4 lbs) was significantly increased in MA-treated patients.
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Dun NJ, Dun SL, Wu SY, Williams CA, Kwok EH. Endomorphins: localization, release and action on rat dorsal horn neurons. J Biomed Sci 2000; 7:213-20. [PMID: 10810239 DOI: 10.1007/bf02255468] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
Abstract
Endomorphin (Endo) 1 and 2, two tetrapeptides isolated from the bovine and human brain, have been proposed to be the endogenous ligand for the mu-opiate receptor. A multi-disciplinary study was undertaken to address the issues of localization, release and biological action of Endo with respect to the rat dorsal horn. First, immunohistochemical studies showed that Endo-1- or Endo-2-like immunoreactivity (Endo-1- or Endo-2-LI) is selectively expressed in fiber-like elements occupying the superficial layers of the rat dorsal horn, which also exhibit a high level of mu-opiate receptor immunoreactivity. Second, release of immunoreactive Endo-2-like substances (irEndo) from the in vitro rat spinal cords upon electrical stimulation of dorsal root afferent fibers was detected by the immobilized antibody microprobe technique. The site of release corresponded to laminae I and II where the highest density of Endo-2-LI fibers was localized. Lastly, whole-cell patch clamp recordings from substantia gelatinosa (SG) neurons of rat lumbar spinal cord slices revealed two distinct actions of exogenous Endo-1 and Endo-2: (1) depression of excitatory and/or inhibitory postsynaptic potentials evoked by stimulation of dorsal root entry zone, and (2) hyperpolarization of SG neurons. These two effects were prevented by the selective mu-opiate receptor antagonist beta-funaltrexamine. The localization of endomorphin-positive fibers in superficial layers of the dorsal horn and the release of irEndo upon stimulation of dorsal root afferents together with the observation that Endo inhibits the activity of SG neurons by interacting with mu-opiate receptors provide additional support of a role of Endo as the endogenous ligand for the mu-opiate receptor in the rat dorsal horn.
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Lai CC, Wu SY, Chen CT, Dun NJ. Nociceptin inhibits rat sympathetic preganglionic neurons in situ and in vitro. Am J Physiol Regul Integr Comp Physiol 2000; 278:R592-7. [PMID: 10712277 DOI: 10.1152/ajpregu.2000.278.3.r592] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
In vitro and in situ experiments were conducted to evaluate the hypothesis that the nonclassical opioid peptide nociceptin acting on sympathetic preganglionic neurons (SPNs) inhibits spinal sympathetic outflow. First, whole cell patch recordings were made from antidromically identified SPNs from immature (12-16 day old) rat spinal cord slices. Nociceptin (0.1, 0.3, and 1 microM) concentration dependently suppressed the excitatory postsynaptic potentials (EPSPs) evoked by focal stimulation and hyperpolarized a population of SPNs; these effects were naloxone insensitive. L-Glutamate-induced depolarizations were not significantly changed by nociceptin. Results from this series of experiments indicate that nociceptin inhibits the activity of SPNs by either a presynaptic or postsynaptic site of action, whereby the peptide reduces, respectively, the amplitude of EPSPs or the excitability of SPNs. Second, intrathecal injection of nociceptin (3, 10, and 30 nmol) to urethan-anesthetized rats dose dependently reduced the mean arterial pressure and heart rate; these effects were not prevented by prior intravenous administration of naloxone (1 mg/kg). Physiological saline given intrathecally was without appreciable effects. These results, together with earlier observations of the detection of nociceptin-immunoreactive nerve fibers and nociceptin receptor immunoreactivity in the rat intermediolateral cell column, raise the possibility that the opioid peptide, which may be released endogenously, reduces spinal sympathetic outflow by depressing the activity of SPNs.
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Hou SY, Wu SY, Zhou T, Thomas MC, Chiang CM. Alleviation of human papillomavirus E2-mediated transcriptional repression via formation of a TATA binding protein (or TFIID)-TFIIB-RNA polymerase II-TFIIF preinitiation complex. Mol Cell Biol 2000; 20:113-25. [PMID: 10594014 PMCID: PMC85067 DOI: 10.1128/mcb.20.1.113-125.2000] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Transcription in human papillomaviruses (HPVs) is mainly regulated by cellular transcription factors and virus-encoded E2 proteins that act as sequence-specific DNA-binding proteins. Although the functions of E2 as a transcriptional activator and a repressor have been well documented, the role of cellular factors involved in E2-mediated regulation of the HPV promoters and the mechanism by which E2 modulates viral gene expression remain unclear. Using reconstituted cell-free transcription systems, we found that cellular enhancer-binding factors and general cofactors, such as TAF(II)s, TFIIA, Mediator, and PC4, are not required for E2-mediated repression. Unlike other transcriptional repressors that function through recruitment of histone deacetylase or corepressor complexes, HPV E2 is able to directly target components of the general transcription machinery to exert its repressor activity on the natural HPV E6 promoter. Interestingly, preincubation of TATA binding protein (TBP) or TFIID with HPV template is not sufficient to overcome E2-mediated repression, which can be alleviated only via formation of a minimal TBP (or TFIID)-TFIIB-RNA polymerase II-TFIIF preinitiation complex. Our data therefore indicate that E2 does not simply work by displacing TBP or TFIID from binding to the adjacent TATA box. Instead, E2 appears to function as an active repressor that directly inhibits HPV transcription at steps after TATA recognition by TBP or TFIID.
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Cortelazzi D, Morpurgo PS, Zamperini P, Fisher DA, Beck-Peccoz P, Wu SY. Maternal compound W serial measurements for the management of fetal hypothyroidsm. Eur J Endocrinol 1999; 141:570-8. [PMID: 10601958 DOI: 10.1530/eje.0.1410570] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
OBJECTIVE The diagnosis of fetal hypothyroidism is based at present on measurements of TSH and free thyroxine (FT4) in fetal blood samples obtained by cordocentesis. The measurement of maternal serum and urinary concentrations of compound W, immunologically similar to but chromatographically distinct from diiodothyronine sulfate (T2S), has been advocated as a new possible marker for fetal hypothyroidism. DESIGN In this paper, we measured serum compound W levels in 84 pregnant women, 20 with and 64 without thyroid disorders before and during specific treatment. Compound W was also assessed in fetal blood obtained by cordocentesis from 49 normal fetuses and 4 fetuses with suspected hypothyroidism due to transplacental passage of propylthiouracil (PTU). Compound W levels were measured by T2S RIA in maternal and fetal serum. To assess the possible usefulness of 3, 5,3'-triiodothyroacetic acid (TRIAC) for therapy of fetal hypothyroidism we evaluated the transplacental passage of TRIAC by administering the drug to four pregnant women before therapeutic abortion. RESULTS In normal pregnancies, both maternal and fetal compound W levels increased progressively during gestation with a significant direct correlation (P<0.001, in both mothers and fetuses). Moreover, a significant positive correlation was observed between fetal compound W and fetal FT4 values (P<0.005), whereas no correlation was observed between maternal serum compound W and maternal FT4 in either euthyroid or hyperthyroid women, suggesting the fetal origin of compound W. The hypothyroid fetuses of PTU-treated mothers showed low compound W levels, and maternal compound W values were in the low normal range and did not show the typical increase during progression of gestation. A significant increase of maternal compound W was observed when the PTU dose was reduced. TRIAC was documented to cross the placental barrier and the treatment of a hyperthyroid pregnant woman on PTU caused the high fetal TSH levels and goiter to normalize. CONCLUSIONS Serial measurements of 3,3'-T2S crossreactive materials (compound W and 3, 3'-diiodothyroacetic acid sulfate) in maternal blood and the administration of TRIAC to the mother may represent a useful and safe alternative to invasive techniques for the diagnosis and therapy of fetal hypothyroidism.
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Wu SY, Polk DH, Huang WS, Fisher DA. Fetal-to-maternal transfer of 3,3',5-triiodothyronine sulfate and its metabolite in sheep. THE AMERICAN JOURNAL OF PHYSIOLOGY 1999; 277:E915-9. [PMID: 10567020 DOI: 10.1152/ajpendo.1999.277.5.e915] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Earlier studies have shown that sulfoconjugation is a major pathway of thyroid hormone metabolism in fetal mammals. To assess the placental transfer of sulfoconjugates in the pregnant sheep model, we measured 3,3',5-triiodothyronine (T(3)) sulfate (T(3)S), 3, 3'-diiodothyronine sulfate (T(2)S), and T(3) concentrations in fetal serum and in maternal serum and urine after T(3)S infusion to the fetus (n = 5) or the ewe (n = 6). Maternal infusion of T(3)S did not increase fetal serum T(2)S, T(3)S, or T(3) concentrations. In contrast, fetal infusion of T(3)S produced significant increases in maternal serum T(2)S and T(3)S but not T(3) concentrations. Fetal T(3)S infusion also increased maternal urine excretion of T(3)S. However, the 4-h cumulative maternal urinary excretion of T(2)S and T(3)S after fetal T(3)S infusion was less than the excretion observed after fetal infusion of equimolar amounts of T(3) in our previous study. It is concluded that fetal serum T(2)S and T(3)S can be transferred to maternal compartments. However, compared with T(3), these sulfoconjugates may be less readily transferred.
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Rajatanavin R, Fisher DA, Chailurkit L, Huang WS, Srisupandit S, Wu SY. A T2S cross-reactive material (compound W) in hyperthyroid patients with trophoblastic disease. Thyroid 1999; 9:989-94. [PMID: 10560952 DOI: 10.1089/thy.1999.9.989] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
In a previous study we observed increased serum levels of a 3,3'-diiodothyronine sulfate (T2S)-like material (compound W) in women who received human chorionic gonadotropin (hCG) treatment. In the present study we assessed serum compound W values in 113 women (total serum sample: 190) with trophoblastic disease, in 7 normal nonpregnant women during the menstrual cycle and 7 women given hCG treatment in the course of in vitro fertilization. Fifty-three women with trophoblastic disease had serum free thyroxine (FT4) concentrations greater than 3.0 ng/dL with suppressed serum thyrotropin (TSH) levels; 61 had FT4 values less than 3.0 ng/dL with a mean TSH of 0.83 mU/L. Mean (+/- SE) compound W concentrations in the high FT4 group were significantly higher than in the low FT4 group (76 +/- 8.1 vs. 21 +/- 1.7 ng T2S equivalent, p < 0.001) There were significant correlations between serum hCG and compound W concentrations (r = 0.472, p < 0.001), serum FT4 and hCG (r = 0.503, p < 0.0001) and serum FT4 and compound W (r = 0.585, p < 0.0001). In nonpregnant women serum compound W levels increased from 7.5 +/- 8 ng/dL at the end of the menstrual period to 15 +/- 1.7 ng/dL 21 days after the last menstrual period. Finally, a single dose of hCG (10,000 USP units, intramuscularly) increased mean (+/- SE) serum compound W levels from 12.8 +/- 2.3 to 64 +/- 9.7 ng/dL and 54 +/- 12 ng/dL at 9 and 16 days, respectively. These results indicate that hCG and perhaps luteinizing hormone (LH) increase serum compound W concentrations in women. The mechanism and significance presently are unclear.
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Leske MC, Wu SY, Hyman L, Li X, Hennis A, Connell AM, Schachat AP. Diabetic retinopathy in a black population: the Barbados Eye Study. Ophthalmology 1999; 106:1893-9. [PMID: 10519582 DOI: 10.1016/s0161-6420(99)90398-6] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
OBJECTIVE The distribution of diabetic retinopathy in black populations is largely unknown. The authors present retinopathy data from the predominately black participants of the Barbados Eye Study (BES). DESIGN AND PARTICIPANTS Prevalence study of 4631 participants based on a random sample of the Barbados population 40 to 84 years of age (84% participation). MAIN OUTCOME MEASURES Diabetes was defined as self-reported history of physician-diagnosed diabetes or glycosylated hemoglobin greater than 10% (>2 standard deviations above the population mean of persons without a diabetes history). Retinopathy was assessed by independent gradings of 30 degrees color stereo fundus photographs of the disc and macula. RESULTS Diabetes was present in 19.4% of black (n = 4314), 15.2% of mixed (black and white; n = 184), and 7.5% of white/other (n = 133) self-reported racial groups. In the black/mixed population, regardless of diabetes status, the prevalence of retinopathy was 5.9%. In the 636 black and mixed participants with diabetes, the prevalence of retinopathy was 28.5%: 19.8% had minimum changes, 7.7% had moderate changes, and 0.9% had severe retinopathy. Clinically significant macular edema (CSME) was found in 8.6% of those with diabetes. CONCLUSIONS In the population of African origin, approximately 1 in 17 persons had retinopathy. Among those with diabetes, 28.5% had retinopathy and 8.6% had CSME. These results highlight the clinical and public health relevance of diabetic retinopathy in the black population.
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Williams CA, Wu SY, Dun SL, Kwok EH, Dun NJ. Release of endomorphin-2 like substances from the rat spinal cord. Neurosci Lett 1999; 273:25-8. [PMID: 10505643 DOI: 10.1016/s0304-3940(99)00613-8] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Release of endomorphin (ENDO)-2 like substances from the dorsal horn of the isolated rat spinal cord was measured by the immobilized-antibody microprobe technique. Spinal cords were removed from anesthetized 4-6 week old rats and superfused with oxygenated Krebs solution at room temperature. Glass microprobes coated with ENDO-2 antibodies were inserted into the dorsal horn of the lumbar spinal cord 1.5 mm lateral to the midline to a depth 2.5 mm below the dorsal surface of the cord. Each probe remained in situ for 10 min periods before, during and after electrical stimulation applied to the dorsal root entry zone of the same spinal segment. There was no detectable basal release of immunoreactive endomorphin-2 like substance (irENDO) from the dorsal horns during the pre-stimulation, nor following the stimulation period. A significant release of irENDO was measured during the electrical stimulation. These results provide the first evidence of a irEndo release that is correlated spatially with the dorsal horn laminae I and II where ENDO-2-immunoreactive fibers are concentrated in the dorsal horn in response to electrical activation of primary afferent fibers.
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Wu SY, Nemesure B, Leske MC. Refractive errors in a black adult population: the Barbados Eye Study. Invest Ophthalmol Vis Sci 1999; 40:2179-84. [PMID: 10476781] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/13/2023] Open
Abstract
PURPOSE To describe the prevalence of refractive errors in a black adult population. METHODS The Barbados Eye Study, a population-based study, included 4709 Barbados-born citizens, or 84% of a random sample, 40 to 84 years of age. Myopia and hyperopia were defined as a spherical equivalent <-0.5 diopters and >+0.5 diopters, respectively, based on automated refraction. Analyses included 4036 black participants without history of cataract surgery. Associations with myopia and hyperopia were evaluated in logistic regression analyses. RESULTS The prevalence of myopia was 21.9% and was higher in men (25.0%) than in women (19.5%). The prevalence of hyperopia was 46.9% and was higher in women (51.8%) than in men (40.5%). The prevalence of myopia decreased from 17% in persons 40 to 49 years of age to 11% in those 50 to 59 years of age, but increased after 60 years of age. The prevalence of hyperopia increased from 29% at 40 to 49 years of age to 65% at 50 to 59 years of age, and tended to decline thereafter. A higher prevalence of myopia was positively associated (P < 0.05) with lifetime occupations requiring nearwork, nuclear opacities, posterior subcapsular opacities, glaucoma, and ocular hypertension. Factors associated with hyperopia were the same as for myopia, except for occupation, and in the opposite direction. CONCLUSIONS High prevalences of myopia and hyperopia were found in this large black adult population. The prevalence of myopia (hyperopia) increased (decreased) after 60 years of age, which is inconsistent with data from other studies. The high prevalence of age-related cataract, glaucoma, and other eye conditions in the Barbados Eye Study population may contribute to the findings.
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Wu SY, Thomas MC, Hou SY, Likhite V, Chiang CM. Isolation of mouse TFIID and functional characterization of TBP and TFIID in mediating estrogen receptor and chromatin transcription. J Biol Chem 1999; 274:23480-90. [PMID: 10438527 DOI: 10.1074/jbc.274.33.23480] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
TFIID is a general transcription factor required for the assembly of the transcription machinery on most eukaryotic promoters transcribed by RNA polymerase II. Although the TATA-binding subunit (TBP) of TFIID is able to support core promoter and activator-dependent transcription under some circumstances, the roles of TBP-associated factors (TAF(II)s) in TFIID-mediated activation remain unclear. To define the evolutionarily conserved function of TFIID and to elucidate the roles of TAF(II)s in gene activation, we have cloned the mouse TAF(II)55 subunit of TFIID and further isolated mouse TFIID from a murine FM3A-derived cell line that constitutively expresses FLAG-tagged mouse TAF(II)55. Both mouse and human TFIIDs are capable of mediating transcriptional activation by Gal4 fusions containing different activation domains in a highly purified human cell-free transcription system devoid of TFIIA and Mediator. Although TAF(II)-independent activation by Gal4-VP16 can also be observed in this highly purified human transcription system with either mouse or yeast TBP, TAF(II)s are strictly required for estrogen receptor-mediated activation independently of the core promoter sequence. In addition, TAF(II)s are necessary for transcription from a preassembled chromatin template. These findings clearly demonstrate an essential role of TAF(II)s as a transcriptional coactivator for estrogen receptor and in chromatin transcription.
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Wu SY, Dun SL, Wright MT, Chang JK, Dun NJ. Endomorphin-like immunoreactivity in the rat dorsal horn and inhibition of substantia gelatinosa neurons in vitro. Neuroscience 1999; 89:317-21. [PMID: 10077314 DOI: 10.1016/s0306-4522(98)00570-3] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Endomorphin 1 and 2 are two tetrapeptides recently isolated from bovine as well as human brains and proposed to be the endogenous ligand for the mu-opiate receptor. Opioid compounds expressing mu-receptor preference are generally potent analgesics. The spinal cord dorsal horn is considered to be an important site for the processing of sensory information including pain. The discovery that endomorphins produced greater analgesia in mice upon intrathecal as compared to intracerebroventricular injections raises the possibility that dorsal horn neurons may represent the anatomic site upon which endomorphins exert their analgesic effects. We report here the detection of endomorphin 2-immunuoreactive fiber-like elements in superficial layers of the rat dorsal horn by immunohistochemical techniques. Whole-cell patch recordings from substantia gelatinosa neurons of cervical spinal cord slices revealed two conspicuous effects of exogenously applied endomorphin 1 and 2: (i) depression of excitatory postsynaptic potentials evoked by stimulation of dorsal root entry zone, and (ii) hyperpolarization of substantia gelatinosa neurons. These effects were reversed by the selective mu-opiate receptor antagonist beta-funaltrexamine. Collectively, the detection of endomorphin-like immunoreactivity in nerve fibers of the superficial layers and the inhibitory action of endomorphins on substantia gelatinosa neurons provide further support for a potential role of these two peptides in spinal nociception.
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