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Williams ML. Making the most of learning needs assessments. JOURNAL FOR NURSES IN STAFF DEVELOPMENT : JNSD : OFFICIAL JOURNAL OF THE NATIONAL NURSING STAFF DEVELOPMENT ORGANIZATION 1998; 14:137-42. [PMID: 9679070 DOI: 10.1097/00124645-199805000-00004] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Identifying learning needs of nurses is an important role of the staff development educator. However, few educators have specific training in the preparation and evaluation of a learning needs assessment. This article describes the assumptions, benefits, and potential barriers when planning a needs assessment survey. Specific strategies to maximize the benefits of the survey are shared. Competent nurses are the cornerstone of professional nursing care, and identifying and responding to learning needs through a needs assessment is a critical step in assuring competence.
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Williams ML, Zhao Z, Freeman RC, Elwood WN, Rusek R, Booth RE, Dennis ML, Fisher DG, Rhodes F, Weatherby NL. A cluster analysis of not-in-treatment drug users at risk for HIV infection. THE AMERICAN JOURNAL OF DRUG AND ALCOHOL ABUSE 1998; 24:199-223. [PMID: 9643462 DOI: 10.3109/00952999809001709] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
The purpose of the analysis described here was to classify not-in-treatment drug users participating in the National Institute on Drug Abuse (NIDA)-sponsored Cooperative Agreement study into several "homogeneous" HIV risk groups using cluster analysis. Data for this analysis (N=17,778) were collected at 19 study sites in the United States and Puerto Rico. Measures selected for the cluster analysis were limited to (a) current drug use and HIV risk behaviors, (b) mutually exclusive behaviors, (c) behaviors directly related to HIV risk, and (d) behaviors that were not statistically rare. Eight homogeneous HIV risk clusters were produced. Crack cocaine use was the most distinguishing feature of three clusters. Another three clusters were distinguishable by drug injection and needle use practices. Two additional clusters could not be grouped with either the crack- or the injection-dominant clusters. Prostitution was the most distinguishing risk behavior of one of these clusters, and extremely high drug injection frequencies and relative rates of risky needle use characterized the other. Composition of the clusters varied significantly by gender, race/ethnicity, educational attainment, and drug use characteristics. In addition, perceptions and behaviors initiated to reduce the chances of becoming infected with HIV varied by cluster. Subjects in the crack-predominant clusters reported low perceptions of the chances of getting AIDS. Perceptions of the chances of becoming infected with HIV among subjects in the injection-predominant clusters were strongly related to injection frequency. Seroprevalence was also related to cluster. Higher rates of HIV infection were evident among the injection-predominant clusters, and higher rates were related to frequency of injection and the rate of risky needle use. Among the crack-predominant clusters, the relationship between drug use and sexual behaviors and HIV infection was less clear.
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Hanley K, Jiang Y, He SS, Friedman M, Elias PM, Bikle DD, Williams ML, Feingold KR. Keratinocyte differentiation is stimulated by activators of the nuclear hormone receptor PPARalpha. J Invest Dermatol 1998; 110:368-75. [PMID: 9540977 DOI: 10.1046/j.1523-1747.1998.00139.x] [Citation(s) in RCA: 143] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Peroxisome proliferator activated receptors (PPAR) belong to the superfamily of nuclear hormone receptors that heterodimerize with the retinoid X receptor and regulate transcription of several genes involved in lipid metabolism and adipocyte differentiation. Because of the role of 1,25-dihydroxyvitamin D3 and retinoic acid working through similar receptors (the vitamin D receptor and retinoic acid receptor, respectively) on keratinocyte differentiation, we have examined the effects of activators of PPARalpha on keratinocyte differentiation. The rate of cornified envelope formation was increased 3-fold in keratinocytes maintained in low calcium (0.03 mM) and incubated in the presence of clofibric acid, a potent PPARalpha activator. Involucrin, a cornified envelope precursor, and the cross-linking enzyme transglutaminase, were increased at both the message level (2-7-fold) and the protein level (4-12-fold) by clofibric acid. Furthermore, physiologic doses of the fatty acids oleic acid, linoleic acid, and eicosatetraynoic acid, which are also activators of PPARalpha, also induced involucrin and transglutaminase protein and mRNA. In contrast, the PPARgammaligand prostaglandin J2 had no effect on protein or mRNA levels of involucrin or transglutaminase. Levels of involucrin and transglutaminase mRNA and protein were induced by clofibric acid in keratinocytes incubated in 1.2 mM calcium, a concentration which by itself induces keratinocyte differentiation. Finally, PPARalpha activators inhibit DNA synthesis. This study demonstrates that PPARalpha activators, including putative endogenous ligands such as fatty acids, induce differentiation and inhibit proliferation in keratinocytes, and suggests a regulatory role for the PPARalpha in epidermal homeostasis.
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Elias PM, Nau P, Hanley K, Cullander C, Crumrine D, Bench G, Sideras-Haddad E, Mauro T, Williams ML, Feingold KR. Formation of the epidermal calcium gradient coincides with key milestones of barrier ontogenesis in the rodent. J Invest Dermatol 1998; 110:399-404. [PMID: 9540982 DOI: 10.1046/j.1523-1747.1998.00151.x] [Citation(s) in RCA: 75] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The epidermal permeability barrier forms late in gestation, coincident with decreased lipid synthesis, increased lipid processing, and development of a mature, multi-layered stratum corneum. Prior studies have shown that changes in the epidermal Ca++ gradient in vivo regulate lamellar body secretion and lipid synthesis, and modulations in extracellular Ca++ in vitro also regulate keratinocyte differentiation. We asked here whether a Ca++ gradient forms in fetal epidermis in utero, and whether its emergence correlates with key developmental milestones of barrier formation and stratum corneum development. Using either ion precipitation or proton induced X-ray emission analysis of fetal mouse and rat skin, we showed that a Ca++ gradient is not present at gestational days 16-18, prior to barrier formation, and that a gradient forms coincident with the emergence of barrier competence (day 19, mouse; day 20, rat) prior to birth. These results are consistent with a role for Ca++ in the regulation of key metabolic events leading to barrier formation. Whether the calcium gradient is formed actively or passively remains to be determined.
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Choate KA, Williams ML, Elias PM, Khavari PA. Transglutaminase 1 expression in a patient with features of harlequin ichthyosis: case report. J Am Acad Dermatol 1998; 38:325-9. [PMID: 9486708 DOI: 10.1016/s0190-9622(98)70575-4] [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: 02/06/2023]
Abstract
Harlequin ichthyosis (HI) is a life-threatening disorder characterized clinically by massive generalized hyperkeratosis and ultrastructurally by an absence of lamellar bodies. However, infants who survive the perinatal period develop a phenotype resembling the nonbullous ichthyosiform erythrodermic (CIE) form of autosomal recessive ichthyosis. We studied a child with a severe hyperkeratotic skin disorder present at birth that developed into a CIE-like phenotype. Electron microscopy demonstrated an absence of lamellar bodies consistent with HI. Abnormalities of filaggrin and involucrin expression by immunostaining were evident. However, transglutaminase 1 (TGase1) was expressed in the epidermis in a pattern consistent with other diseases that involve epidermal acanthosis. Analysis of patient keratinocytes grown in vitro demonstrated expression of normal amounts of TGase1 mRNA and full length TGase1 protein, as well as normal levels of transglutaminase enzymatic activity.
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Choate KA, Williams ML, Khavari PA. Abnormal transglutaminase 1 expression pattern in a subset of patients with erythrodermic autosomal recessive ichthyosis. J Invest Dermatol 1998; 110:8-12. [PMID: 9424079 DOI: 10.1046/j.1523-1747.1998.00070.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
An autosomal recessive ichthyosis characterized by collodian membrane at birth followed by generalized skin redness and fine, light-colored scales has been termed nonbullous congenital ichthyosiform erythroderma (CIE). CIE has often been classified together with the other major form of recessive ichthyosis without internal organ involvement, lamellar ichthyosis, which is characterized by minimal erythema and a coarser, darker scale pattern. Recently, autosomal recessive ichthyosis has been associated with keratinocyte transglutaminase (TGase1) defects in some patients. This group of diseases, however, is genetically heterogeneous and TGase1 abnormalities in CIE have not been clearly described. Therefore we examined TGase1 expression in five patients with CIE and three with classic lamellar ichthyosis. Although lamellar ichthyosis patients displayed no TGase1 expression, an abnormal intracellular accumulation of TGase1 was observed in four of five CIE patients. This finding was specific and was not observed in other skin disorders characterized by erythema and abnormal cornification, including erythrodermic psoriasis, atopic dermatitis, epidermolytic hyperkeratosis, and Netherton's syndrome. CIE keratinocytes with abnormal TGase1 localization expressed full-length TGase1 mRNA and protein but demonstrated transglutaminase activity intermediate between normal and the minimal activity seen in lamellar ichthyosis patient cells. The abnormal TGase1 expression pattern and CIE clinical features were recapitulated in epidermis regenerated in vivo on immune deficient mice from CIE patient keratinocytes. These studies describe a specific abnormality in TGase1 intrinsic to keratinocytes in a subset of CIE patients and suggest that this abnormality may be involved in the disordered epidermal differentiation seen in this disorder.
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Reed RP, Robins-Browne RM, Williams ML. Yersinia enterocolitica peritonitis. Clin Infect Dis 1997; 25:1468-9. [PMID: 9431397 DOI: 10.1086/516122] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
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Hanley K, Devaskar UP, Hicks SJ, Jiang Y, Crumrine D, Elias PM, Williams ML, Feingold KR. Hypothyroidism delays fetal stratum corneum development in mice. Pediatr Res 1997; 42:610-4. [PMID: 9357932 DOI: 10.1203/00006450-199711000-00010] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The epidermal permeability barrier, required for terrestrial life, is localized to lipid-enriched lamellar membranes in the extracellular spaces of the stratum corneum (SC). Immaturity of the SC is a significant contributor to morbidity and mortality in premature infants. Previous studies have shown that supraphysiologic concentrations of thyroid hormone accelerate epidermis/SC ontogenesis. Here we studied SC development in Hyt/Hyt mice who are genetically hypothyroid due to a mutation in the TSH receptor. In control mice on d 18 of gestation (term 19.5 d), only focal areas displayed a mature SC membrane pattern. By 19 d of gestation there was a mature multilayered SC with lamellar unit structures filling the extracellular spaces similar to that seen in mature mice. In Hyt/Hyt mice SC development was delayed at both 18 and 19 d of gestation. In both strains of mice, within the first day after birth there were no differences in epidermal or SC appearance, and the SC was fully mature. These findings indicate that thyroid hormone plays a physiologic role during normal intrauterine development of the SC. However, normal SC maturation ultimately occurs, indicating that thyroid hormone is not absolutely essential. Previous studies have shown that glucocorticoids accelerate SC development in euthyroid rats, and in the present study we demonstrate that glucocorticoids also accelerate SC ontogenesis in euthyroid mice. In contrast, in Hyt/Hyt mice glucocorticoids did not accelerate or normalize SC development, indicating that the glucocorticoid effect on SC maturation requires a euthyroid state or that glucocorticoids act via thyroid hormone. These studies demonstrate that thyroid hormone status is an important regulator of fetal SC development.
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Williams ML, Zhao Z, Bowen AM, Freeman RC, Elwood WN, Rusek R. Introduction of HIV into drug injector networks outside AIDS epicentres. Int J STD AIDS 1997; 8:629-35. [PMID: 9310222 DOI: 10.1258/0956462971918896] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Injection drug users (IDUs) continue to be at risk for HIV infection despite high levels of knowledge about how human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS) is transmitted. Yet, among not-in-treatment injection drug users, the chances of becoming infected with HIV vary substantially. Information regarding the factors that facilitate the introduction of HIV into networks of drug injectors in low HIV seroprevalence cities is urgently needed. This study examines the factors related to HIV seroprevalence in a large (n=9492), multi-site sample of IDUs recruited in 11 low seroprevalence cities. Univariate and multivariate associations between drug injection and sexual behaviours and travel to an AIDS epicentre were examined. Results show that, next to male-to-male sexual contact, having sex at least twice in an AIDS epicentre was the strongest predictor of HIV infection. Also associated with higher odds of being HIV-positive were racial/ethnic characteristics, daily drug injection, and injecting drugs in an AIDS epicentre. These results confirm that travelling to an AIDS epicentre and having sex or injecting drugs play a large role in the introduction of HIV into drug injector networks in low seroprevalence cities.
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Williams ML, Donaldson C, Watts J. Developing an orientation program for assistive personnel in the ICU. Dimens Crit Care Nurs 1997; 16:266-73. [PMID: 9335666 DOI: 10.1097/00003465-199709000-00009] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Assistive personnel are being used in intensive care unit (ICU) settings in response to the demand for more cost-effective nursing care. Nurse managers, educators, and advanced practice nurses must address the unique orientation needs of these workers. A comprehensive, competency-based orientation program for assistive personnel can help the ICU technician be successful. Despite the multitude of assistive personnel being used in the critical care settings, little information is available regarding the development of an orientation program for ICU technicians. This article discusses one ICU's experience in developing an orientation program for their ICU technicians.
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Hanley K, Jiang Y, Crumrine D, Bass NM, Appel R, Elias PM, Williams ML, Feingold KR. Activators of the nuclear hormone receptors PPARalpha and FXR accelerate the development of the fetal epidermal permeability barrier. J Clin Invest 1997; 100:705-12. [PMID: 9239419 PMCID: PMC508240 DOI: 10.1172/jci119583] [Citation(s) in RCA: 117] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Members of the superfamily of nuclear hormone receptors which are obligate heterodimeric partners of the retinoid X receptor may be important in epidermal development. Here, we examined the effects of activators of the receptors for vitamin D3 and retinoids, and of the peroxisome proliferator activated receptors (PPARs) and the farnesoid X-activated receptor (FXR), on the development of the fetal epidermal barrier in vitro. Skin explants from gestational day 17 rats (term is 22 d) are unstratified and lack a stratum corneum (SC). After incubation in hormone-free media for 3-4 d, a multilayered SC replete with mature lamellar membranes in the interstices and a functionally competent barrier appear. 9-cis or all-trans retinoic acid, 1,25 dihydroxyvitamin D3, or the PPARgamma ligands prostaglandin J2 or troglitazone did not affect the development of barrier function or epidermal morphology. In contrast, activators of the PPARalpha, oleic acid, linoleic acid, and clofibrate, accelerated epidermal development, resulting in mature lamellar membranes, a multilayered SC, and a competent barrier after 2 d of incubation. The FXR activators, all-trans farnesol and juvenile hormone III, also accelerated epidermal barrier development. Activities of beta-glucocerebrosidase and steroid sulfatase, enzymes previously linked to barrier maturation, also increased after treatment with PPARalpha and FXR activators. In contrast, isoprenoids, such as nerolidol, cis-farnesol, or geranylgeraniol, or metabolites in the cholesterol pathway, such as mevalonate, squalene, or 25-hydroxycholesterol, did not alter barrier development. Finally, additive effects were observed in explants incubated with clofibrate and farnesol together in suboptimal concentrations which alone did not affect barrier development. These data indicate a putative physiologic role for PPARalpha and FXR in epidermal barrier development.
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Elwood WN, Williams ML, Bell DC, Richard AJ. Powerlessness and HIV prevention among people who trade sex for drugs ('strawberries'). AIDS Care 1997; 9:273-84. [PMID: 9290833 DOI: 10.1080/713613155] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Researchers and members of the drug culture have employed the term 'strawberries' to describe African American women who trade sex for drugs. Data from six US cities participating in a community-based drug research project were analysed to examine the determinants of trading sex for drugs. As shown by our data, some African American women match the street description commonly attributed to 'strawberries'. However, our results also show that trading sexual favours for drugs is not limited to African American women, nor solely to women. Rather, trading sex for drugs is an economic behaviour that occurs among women and men of any race/ethnicity who use crack cocaine. Trading sex for drugs is closely related to conditions of poverty and homelessness, conditions that especially affect many crack smokers. The discussion urges educators and researchers to be alert for 'strawberry behaviours' exhibited by drug-users of any racial/ethnic background or gender.
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Hanley K, Jiang Y, Katagiri C, Feingold KR, Williams ML. Epidermal steroid sulfatase and cholesterol sulfotransferase are regulated during late gestation in the fetal rat. J Invest Dermatol 1997; 108:871-5. [PMID: 9182813 DOI: 10.1111/1523-1747.ep12292586] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Lipids in the stratum corneum (SC) are organized into lamellar membrane unit structures that provide the permeability barrier. Cholesterol sulfate, a SC membrane lipid, is synthesized by cholesterol sulfotransferase (CSTase) in the lower epidermis and hydrolyzed to cholesterol by steroid sulfatase (SSase) in the SC. To determine whether these enzymes are induced during barrier ontogenesis, we examined their activity in epidermis of fetal rats before (gestational day 17), during (day 19), and after (day 21) barrier formation. CSTase activity increased approximately 10-fold between day 17 and day 19, then declined between day 19 and day 21. In contrast, SSase activity reached its peak activity on day 21, increasing >5-fold. Fetal rat skin explants develop a SC and barrier over the same time course in vitro as in utero. Likewise, CSTase and SSase activities during in vitro ontogenesis precisely mirrored those obtained in utero. Moreover, hormones that accelerate barrier ontogenesis (e.g. glucocorticoids, thyroid hormone, and estrogen) accelerated the increase in CSTase and SSase activities during in vitro ontogenesis. mRNA levels of SSase increased in parallel with enzymatic activity, suggesting that these developmental changes are regulated at the genomic level. Finally, addition of exogenous cholesterol sulfate to explants in vitro did not accelerate either SC development or barrier formation. These studies suggest that induction of the cholesterol sulfate cycle enzymes during SC ontogenesis is a component of the fetal epidermal differentiation program and that the synthetic and degradative enzymes of this pathway are differentially regulated.
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Williams ML, Robertson K. Workplace violence. Prevalence, prevention, and first-line interventions. Crit Care Nurs Clin North Am 1997; 9:221-9. [PMID: 9214890] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Workplace violence is increasing, but through education, prevention, and man aging escalating crises, critical care nurses can help to minimize the negative consequences of violence. Critical care nurses are particularly prone to acts of aggression and acts of violence due to the stressful environment for them, their families, and their patients. Developing violence prevention skills and interpersonal communication skills, not always highly valued in a critical care environment, are important steps in deterring workplace violence. Although not all incidents of workplace violence can be prevented, recognizing the individual at risk for violence and intervening on the behalf of all involved is a responsibility of every employee including the critical care nurse.
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Fenner PJ, Lewis RJ, Williamson JA, Williams ML. A Queensland family with ciguatera after eating coral trout. Med J Aust 1997; 166:473-5. [PMID: 9152341 DOI: 10.5694/j.1326-5377.1997.tb123219.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Ciguatera (poisoning caused by eating fish contaminated with algal toxins) is usually diagnosed clinically. We describe a Queensland family of four (including a pregnant woman) with ciguatera, confirmed by bioassay of the implicated fish for ciguatoxin. All four recovered, illustrating the effectiveness of treatment with intravenous mannitol. At birth, the infant appeared to suffer no adverse effects attributable to ciguatera; to our knowledge, this is the first report of the effect of severe ciguatera in the first trimester of pregnancy.
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Kanda A, Watanabe I, Williams ML, Engle CL, Li S, Koch GG, Gettes LS. Unanticipated lessening of the rise in extracellular potassium during ischemia by pinacidil. Circulation 1997; 95:1937-44. [PMID: 9107183 DOI: 10.1161/01.cir.95.7.1937] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
BACKGROUND The efflux of potassium (K) through the ATP-sensitive K channel is considered an important cause of the rise in extracellular K ([K+]e) during no-flow ischemia. We postulated that agents that enhance K conductance in this channel would enhance the rise in [K+]e. METHODS AND RESULTS We studied the effects of 10 and 25 mumol/L pinacidil, and ATP-sensitive K channel opener that provides metabolic protection to the ischemic myocardium, on the rise in [K+]e recorded by K-sensitive electrodes, the change in action potential duration (APD) recorded by microelectrodes, and the changes in activation during ischemia in in situ pig hearts and Tyrode-perfused rabbit interventricular septa. Pinacidil 25 mumol/L unexpectedly lessened the rise in [K+]e and the activation delay in both preparations. Pinacidil 10 mumol/L had no effect in the rabbit and only a slight effect in the pig. Both concentrations significantly exaggerated the APD shortening induced by ischemia. By varying stimulation frequency, we demonstrated that the rise in [K+]e during ischemia, both before and after pinacidil, correlated with the time that the action potential was at its plateau voltage. CONCLUSIONS Our results indicate that the rise in [K+]e during ischemia is due to multiple factors, including K conductance across membrane channels, K driving force as reflected by the time that the action potential is at its plateau voltage, and the metabolic effects of ischemia. The unanticipated lessening of the rise in [K+]e by pinacidil reflects the balance of its effects on these several parameters.
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Williams ML, Maynard RL. Exposure to benzo[a]pyrene. Lancet 1997; 349:652. [PMID: 9057757 DOI: 10.1016/s0140-6736(05)61601-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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Hanley K, Jiang Y, Holleran WM, Elias PM, Williams ML, Feingold KR. Glucosylceramide metabolism is regulated during normal and hormonally stimulated epidermal barrier development in the rat. J Lipid Res 1997; 38:576-84. [PMID: 9101438] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Glucosylceramides, delivered to the stratum corneum interstices by exocytosis of lamellar body contents, are enzymatically hydrolyzed to ceramides, which are major components of the lipid lamellar bilayers that mediate epidermal barrier function. Because this conversion is critical for permeability barrier homeostasis in the adult animal, in this study we measured the changes in activities of the enzymes responsible for the synthesis of glucosylceramide and its conversion to ceramide, UDP-glucose:ceramide glucosyltransferase (GC synthase) and beta-glucocerebrosidase (beta-GlcCer'ase), respectively, during fetal barrier formation. In epidermis from rats of gestational age 17-21 days, GC synthase activity peaked on day 19, prior to barrier competence, whereas beta-GlcCer'ase activity rose throughout barrier formation, exhibiting a 5-fold increase over this time period. beta-GlcCer'ase protein rose in parallel with activity, as did mRNA levels. Enzyme activities in skin explants from 17-day fetal rats, incubated up to 4 days in hormone- and serum-free media, paralleled those measured at corresponding time points in utero. Incubation with hormones that accelerate barrier development had minimal effects on GC synthase activity, whereas beta-GlcCer'ase activity was significantly increased after 1 or 2 days in culture. Finally, inhibition of beta-GlcCer'ase with conduritol B epoxide prevented barrier development in vitro and was accompanied by abnormalities in the lamellar bilayer ultrastructure of the stratum corneum. These data indicate that both synthesis and hydrolysis of glucosylceramide are regulated during fetal development. Furthermore, the enzymatic hydrolysis of glucosylceramide to ceramide is essential for fetal barrier ontogenesis.
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Abstract
Immaturity of the epidermal barrier in the preterm infant may have serious clinical consequences. However, regardless of the degree of prematurity, the barrier rapidly matures such that by 2 wk all infants display a competent barrier. To determine whether the change from an aqueous (intrauterine) to a xeric environment might be the stimulus for this accelerated maturation, we examined the effects of air exposure on cutaneous barrier formation in vitro. Skin explants from d 17 fetal rats were incubated either submerged or at the air-medium interface. As previously reported, a competent barrier formed under submerged conditions after 3-4 d, precisely mirroring the time course of maturation in utero. In contrast, barrier maturation was accelerated in air-exposed explants, with functional, histologic, and structural markers of barrier formation observed after only 2 d of incubation. A water-impermeable membrane blocked the acceleration of barrier formation, resulting in a developmental time course comparable to that for submerged explants. In contrast a water vapor-permeable membrane did not block the acceleration. Glucocorticoids and thyroid hormone, which accelerate barrier formation in utero or in vitro under submerged conditions, did not further accelerate barrier formation in the air-exposed model. These data indicate that: 1) air exposure accelerates barrier ontogenesis, suggesting that water flux may be an important signal for the accelerated barrier formation that occurs in premature infants; and 2) factors which accelerate barrier formation in utero may not further accelerate barrier formation in neonates.
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Williams ML, Rimm DL, Pedigo MA, Frable WJ. Atypical squamous cells of undetermined significance: correlative histologic and follow-up studies from an academic medical center. Diagn Cytopathol 1997; 16:1-7. [PMID: 9034728 DOI: 10.1002/(sici)1097-0339(199701)16:1<1::aid-dc2>3.0.co;2-m] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The diagnosis of ASCUS (atypical squamous cells of undetermined significance) was introduced in the 1988 Bethesda System for reporting cervical/vaginal cytologic findings. Outcome and appropriate management of patients with this diagnosis is not presently established. Criteria defining ASCUS are nuclear enlargement (2.5-3.0 times normal intermediate cell nucleus), mild nuclear hyperchromasia, smooth nuclear outlines with mild variation in nuclear size and shape, or else two, but not all three, cytologic criteria for human papilloma virus (HPV) cytopathic effect. All 668 cases reported as ASCUS from February 1992-December 1993 from our cytology laboratory were reviewed. These ASCUS cases represented 4.5% of all gynecologic cases diagnosed in that same time period. Of these, 284 (41%) had a subsequent colposcopic biopsy and/or endocervical curettage. The biopsied cases included 101 (36%) with condylomata, 38 (13%) with cervical intraepithelial neoplasia (CIN) I, 17 (6%) with CIN II, and 9 (3%) with CIN III. No cases of carcinoma were detected. Of patients with a cytologic diagnosis of ASCUS and subsequent cervical biopsy, 49% had low-grade cervical intraepithelial neoplasia (LGSIL), either condyloma or CIN I. Nine percent had high-grade cervical intraepithelial neoplasia, either CIN II or CIN III. These findings indicate that ASCUS defines cytologically a group of patients who may have either a concurrent or subsequent development of a squamous intraepithelial lesion (SIL). This forms a high-risk group. The management of cases with a cytologic diagnosis of ASCUS should be at least as aggressive as that of LGSIL.
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Williams ML, Elwood WN, Weatherby NL, Bowen AM, Zhao Z, Saunders LA, Montoya ID. An assessment of the risks of syphilis and HIV infection among a sample of not-in-treatment drug users in Houston, Texas. AIDS Care 1996; 8:671-82. [PMID: 8993717 DOI: 10.1080/09540129650125380] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The research presented in this paper details the results of an assessment of the risk factors associated with having a positive syphilis or HIV serology. The study was conducted using a sample of not-in-treatment drug users volunteering to participate in an HIV risk reduction intervention. The sample was composed of individuals who had injected drugs within 30 days or smoked crack cocaine 48 hours prior to participation in the study. Study participants were approximately 75% male and 66% African-American. All participants provided a blood sample to be tested for HIV and syphilis. Analysis of risk was conducted using univariate and multivariate statistical methods. Multivariate analysis of blood results showed that women, African-Americans, and those having a positive blood test for HIV were at higher odds of having a positive syphilis test. Analysis also showed that being a gay or bisexual male, having a history of drug injection, having less than a high-school education, having a history of trading sex for money, being African-American, and having a positive blood test for syphilis significantly increased the odds of a positive HIV test. Implications for HIV and STD prevention are discussed.
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97
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Choate KA, Kinsella TM, Williams ML, Nolan GP, Khavari PA. Transglutaminase 1 delivery to lamellar ichthyosis keratinocytes. Hum Gene Ther 1996; 7:2247-53. [PMID: 8953315 DOI: 10.1089/hum.1996.7.18-2247] [Citation(s) in RCA: 65] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Therapeutic gene delivery in severe genetic skin disease may require production of a uniformly corrected population of cells capable of regeneration of normal skin elements when returned to the host. To achieve this, we have used lamellar ichthyosis (LI), a disorder of epidermal differentiation recently associated with defects in keratinocyte transglutaminase (TGase1), as a prototype. We have used a high-efficiency retroviral delivery approach to uniformly restore normal levels of TGase1 expression to primary keratinocytes from severely affected LI patients previously lacking TGase1. Delivered TGase1 was correctly targeted to membrane association and restored patient cell transglutaminase activity levels to normal. Corrected primary LI patient keratinocytes also demonstrated restoration of previously defective involucrin cross-linking and in vitro measures of cornification to levels found in normal cells. These results indicate that efficient TGase1 delivery to early passage keratinocytes can produce a population of corrected LI patient cells. The capability to produce such cells may provide a basis for future efforts at gene therapy for genetic skin disease.
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98
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Olmstead DL, Williams ML. Billing for CRNP services. PENNSYLVANIA MEDICINE 1996; 99:26-9. [PMID: 8993073] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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99
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Fung MA, Frieden IJ, LeBoit PE, Berger TG, Epstein E, Kay D, Van SL, Williams ML. Confluent and reticulate papillomatosis: successful treatment with minocycline. ARCHIVES OF DERMATOLOGY 1996; 132:1400-1. [PMID: 8915335] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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100
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