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1.
Dermatol Surg ; 27(7): 648-53; discussion 653-4, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11442617

RESUMO

BACKGROUND: A dermal regeneration template indicated for life-threatening third-degree burn injuries is a product with potential application to smaller wounds to aid in healing and closure of complex excision sites. OBJECTIVE: To assess the effectiveness of dermal regeneration template for closure of skin cancer excision sites that would have otherwise required complicated closures. METHODS: Five patients, 61-84 years old, with skin cancer surgery yielding a total of six wounds were treated with the dermal regeneration template to close and heal their wounds. RESULTS: Four of five patients had complete healing (five of six wounds) with cosmetically acceptable results. The one treatment failure was application of the dermal regeneration template over exposed skull where inadequate neodermis formed. Successful healing was observed in five complex skin cancer excision sites including two wounds in previously irradiated grafted skin, a large and deep temporal defect, a wide excision in the supraclavicular region, and an excision down to cartilage on the antihelix of the ear. No infections were noted, although in four of five patients prophylactic oral antibiotics (either erythromycin or cephalexin) were prescribed postoperatively for 1-2 weeks. CONCLUSION: The product simplified wound care, subjectively appeared to decrease pain and postoperative bleeding, and yielded cosmetically acceptable wound repair. Autografting was not necessary; wounds healed in 2-4 months by epithelialization over neodermis after removal of the silicone layer. Furthermore, the product was a convenient long-term dressing and healing device for wounds where complex repairs, autografts, and/or flaps would otherwise be considered for closure.


Assuntos
Neoplasias Cutâneas/cirurgia , Pele Artificial , Cicatrização , Idoso , Idoso de 80 Anos ou mais , Derme/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Cuidados Pós-Operatórios , Regeneração
2.
J Am Acad Dermatol ; 43(2 Pt 1): 281-5, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10906652

RESUMO

The definitions of psoriasis severity and clinically significant improvement in psoriasis are used to classify treatments, obtain Food and Drug Administration approval, and determine product labeling and reimbursement. The Medical Advisory Board of the National Psoriasis Foundation has addressed these issues because of their importance in the clinical trials that are conducted to gain FDA approval of indications. Narrow indications, which are without a sound rational basis, will-in this era of constant oversight by third party payers-affect physicians' ability to manage patients with psoriasis. Body surface area (BSA) is usually used to define severity for clinical trials. It is not optimal for defining psoriasis severity because there are some patients with low BSA involvement who have very severe psoriasis and some patients with high BSA involvement who have mild psoriasis. We conclude that a quality of life (QOL) standard is better than BSA measurement for identifying patients with severe psoriasis. The second issue is what defines clinically significant improvement for patients with psoriasis. Setting an arbitrarily high criterion of clinical efficacy for new psoriasis treatments will likely limit the development and approval of useful treatments. To maximize the availability of useful psoriasis treatments, it is our thesis that psoriasis treatments should be approved when they have been shown to produce a statistically significant level of improvement in well-designed clinical trials.


Assuntos
Psoríase/tratamento farmacológico , Humanos , Qualidade de Vida , Indução de Remissão , Índice de Gravidade de Doença
3.
Cardiovasc Surg ; 7(6): 633-9, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10519672

RESUMO

Vitamin A and its derivatives (retinoids) are capable of inhibiting vascular smooth muscle cell proliferation in vitro. The present study examines the effect of two retinoids, all-trans retinoic acid and 13-cis retinoic acid, on intimal hyperplasia following arterial injury. After receiving varying doses of all-trans retinoic acid or 13-cis retinoic acid, 78 male Sprague-Dawley rats underwent standard balloon catheter denudation of the left common carotid artery. Morphometric analysis and immunohistochemistry for proliferating cell nuclear antigen was performed at early and late time points. Intimal/medial ratios were reduced in a dose-dependent fashion for animals treated with all-trans retinoic acid (P = 0.001) and 13-cis retinoic acid (P = 0.004). Proliferating cell nuclear antigen labeling indices were reduced after treatment with all-trans retinoic acid and 13-cis retinoic acid at early time points post-injury. At a dose of 10 mg/kg, both all-trans retinoic acid and 13-cis retinoic acid inhibited vessel remodeling as measured by increases in luminal diameter (P < 0.05) and external elastic lamina (P < 0.05). Retinoids are an attractive clinical option for the treatment of restenosis following angioplasty and arterial surgery.


Assuntos
Lesões das Artérias Carótidas/patologia , Artéria Carótida Primitiva/efeitos dos fármacos , Isotretinoína/farmacologia , Tretinoína/farmacologia , Túnica Íntima/efeitos dos fármacos , Animais , Artéria Carótida Primitiva/patologia , Cateterismo , Hiperplasia , Masculino , Antígeno Nuclear de Célula em Proliferação/análise , Ratos , Ratos Sprague-Dawley , Túnica Íntima/patologia
4.
J Am Acad Dermatol ; 35(5 Pt 1): 690-5, 1996 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8912562

RESUMO

BACKGROUND: Phototherapy and activated froms of vitamin D help clear psoriasis. OBJECTIVE: The influence of UVB phototherapy and oral calcitriol (1,25-dihydroxyvitamin D3) on vitamin D photosynthesis was assessed in 16 patients. METHODS: Patients were randomly selected to receive orally either placebo or calcitriol (0.5 to 2 micrograms daily) for the duration of the 8-week study; all patients received approximately 21 UVB treatments. Before and after treatment, serum levels of 25-hydroxyvitamin D and calcitriol were measured by high-pressure liquid chromatography. RESULTS: Although calcitriol had no additive effect on phototherapy as a treatment modality, a significant increase in serum 25-hydroxyvitamin D levels occurred in both groups; in three patients extraordinarily high levels developed (> 120 ng/ml). Oral calcitriol significantly increased calcitriol serum levels. Increased serum calcitriol did not inhibit cutaneous synthesis of vitamin D or its hepatic conversion to serum 25-hydroxyvitamin D. CONCLUSION: UVB induces high levels of vitamin D photosynthesis. Because oral or topical calcitriol alone helps clear psoriasis, studies to explore the possible influence of UVB phototherapy on its production should be considered. If UVB phototherapy induces cutaneous calcitriol synthesis this could explain the lack of added benefit to treatment when oral calcitriol is administered with phototherapy.


Assuntos
Calcitriol/administração & dosagem , Psoríase/metabolismo , Psoríase/terapia , Terapia Ultravioleta , Vitamina D/biossíntese , Administração Oral , Adulto , Humanos
5.
Biochem J ; 319 ( Pt 2): 641-8, 1996 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-8912706

RESUMO

Several studies have suggested that murine and human keratinocytes respond differently to phorbol 12-myristate 13-acetate (PMA). Using an in vitro assay, we found that in contrast to its effect on murine skin, PMA did not induce ornithine decarboxylase (ODC) activity in human skin biopsies. To explore the signalling induced by PMA and to determine whether an in vitro culture system could be used to predict biological activity of retinoids in human keratinocytes, we studied a simian virus 40 (SV40)-transformed human keratinocyte cell line. Epidermal growth factor (EGF) stimulates ODC activity and increases the steady-state level of ODC mRNA in a dose- and time-dependent manner in these cells [Prystowsky, Clevenger and Zheng (1993) Exp. Dermatol. 2, 125-132]. In this report, 10(-10) M-10(-7) M PMA induced ODC mRNA and enzyme synthesis at 7 h, but did not significantly induce ODC activity and inhibited the EGF induction of ODC activity. To explore the mechanism whereby PMA interfered with EGF signalling, the effect of PMA on EGF binding to its cell-surface receptor was studied; acute treatment with PMA (within 7 h) decreased EGF binding to 41-57% of the baseline level. In contrast, chronic treatment with PMA (24 h) increased EGF binding to 156% of the baseline level and was associated with an increase in quantity of EGF receptor protein. Protein kinase C (PKC) activation correlated with the acute decrease in EGF binding following PMA treatment. In summary, PMA induced ODC mRNA and ODC enzyme synthesis, while steady-state levels of immunoprecipitable ODC enzyme protein and ODC activity were not increased, demonstrating possible increased turnover of ODC enzyme protein. Additionally, PMA inhibited the induction of ODC by EGF through decreased EGF binding, possibly mediated by PKC activation. Finally treatment of the keratinocytes with retinoids including etretinate, Ro13-7410, etarotene, Ro40-8757, 13-cisretinoic acid, and acitretin blocked the PMA induction of ODC mRNA, suggesting this in vitro model could be a valuable screening assay for predicting biological activity in humans.


Assuntos
Fator de Crescimento Epidérmico/farmacologia , Fosfatos de Inositol/farmacologia , Queratinócitos/metabolismo , Ornitina Descarboxilase/biossíntese , Transdução de Sinais/efeitos dos fármacos , Acetato de Tetradecanoilforbol/farmacologia , Células Cultivadas , Regulação para Baixo , Humanos , RNA Mensageiro/biossíntese
7.
J Am Acad Dermatol ; 34(5 Pt 2): 911-4, 1996 May.
Artigo em Inglês | MEDLINE | ID: mdl-8621827

RESUMO

Severe morbidity and mortality may be associated with erythrodermic psoriasis, especially when complicated by septicemia. We describe five patients with erythrodermic psoriasis complicated by staphylococcal septicemia. In two, concurrent infection with HIV increased vulnerability to bacteremia.


Assuntos
Psoríase/complicações , Sepse/complicações , Infecções Estafilocócicas/complicações , Adulto , Infecções por HIV/complicações , Humanos , Masculino , Pessoa de Meia-Idade
9.
Cutis ; 57(2): 113-8, 1996 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8646856

RESUMO

The objective of this study was to assess the potential interference of topical agents commonly used in psoriasis with concurrent phototherapy. Twenty-one commercially available topical agents were tested. To create solutions from the creams, lotions, and ointments, extractions were made using three different solvents (95 percent ethanol, hexanes, and 1,4-dioxane) and their absorbance from 260 to 400 nm was measured. The absorbance value of the solutions at 310 nm was used to rank the various agents in terms of potential interference with ultraviolet B (UVB) phototherapy. The absorbance at 360 nm was used to rank the agents for potential interference with psoralen/ultraviolet A (PUVA) therapy. Salicylic acid-containing preparations had substantial absorption in the UVB (280 to 320 nm) range. The tar-based products had impressive absorbance in both the UVA (320 to 400 nm) and UVB ranges. Calcipotriene (Dovonex) showed a maximal absorbance in the ultraviolet C (UVC; 200 to 280 nm) and UVB range. Tretinoin (Retin-A) had substantial absorbance in the UVA range. Anthralin (Drithocreme) revealed maximal absorbance within the UVC and UVB ranges. Topical steroid preparations and ammonium lactate (Lac-Hydrin) had low absorbance in both UVB and UVA ranges. In conclusion, salicylic acid-containing preparations, tar-based products, calcipotriene, anthralin, and most tretinoin preparations should be removed before and/or applied after phototherapy.


Assuntos
Fármacos Dermatológicos/administração & dosagem , Psoríase/terapia , Terapia Ultravioleta , Administração Tópica , Adulto , Avaliação Pré-Clínica de Medicamentos/métodos , Humanos , Masculino , Terapia PUVA
10.
Dermatol Clin ; 13(4): 757-70, 1995 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8785881

RESUMO

Pustular psoriasis and erythrodermic psoriasis are generally less stable, more challenging to treat, and more severe for the patient than classical plaque-type psoriasis vulgaris. The risk for systemic infection and overwhelming sepsis in these forms of psoriasis emphasizes the potential life-threatening impact of psoriasis. Careful attention to management strategies enables the astute clinician to help the patient improve, despite the challenges these difficult forms of psoriasis present.


Assuntos
Psoríase/classificação , Infecções Bacterianas/complicações , Dermatite Esfoliativa/patologia , Humanos , Psoríase/complicações , Psoríase/tratamento farmacológico , Psoríase/patologia , Psoríase/terapia
11.
Biochem J ; 309 ( Pt 1): 159-65, 1995 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-7619051

RESUMO

Treatment of SV40-transformed keratinocytes (Z114) with epidermal growth factor (EGF) resulted in an increase in ornithine decarboxylase (ODC) activity and a dose-dependent increase in ODC mRNA levels. Pretreatment of keratinocytes with all-trans-retinoic retinoic acid inhibited the EGF induction of ODC activity. In both quiescent and EGF-stimulated cells, all-trans-retinoic acid inhibited ODC gene transcription and lowered ODC mRNA levels, whereas glyceraldehyde phosphate dehydrogenase expression remained unaffected. Treatment with all-trans-retinoic acid for 24 h resulted in a dose- and time-dependent decrease of up to 52% in EGF binding to EGF receptors and a 30-75% decrease in EGF-receptor quantity. In addition, when cells were treated with both UV radiation and all-trans-retinoic acid, their effects were additive in causing a decrease in EGF binding. Blocking of EGF receptors with a neutralizing antibody for EGF receptors inhibited the induction of ODC activity by EGF. The effects of several other retinoids, including Ro15-0778, etretinate, Ro13-7410, etarotene, Ro40-8757, 13-cis-retinoic acid and acitretin, were also studied to determine their effects on EGF binding and ODC activity. Two of these other retinoids, 13-cis-retinoic acid and Ro13-7410, inhibited EGF binding the most (35-46%, P < 0.001); several others (etarotene, Ro40-8757 and etretinate) were less effective (7-16%), but significantly decreased EGF binding (P < 0.05), and two retinoids (Ro15-0778 and acitretin) showed no significant effect on EGF binding. In contrast, all of the retinoids tested inhibited the induction of ODC activity by EGF, although etretinate and Ro15-0778 were less effective. EGF signal transduction is important in ODC gene regulation, and retinoids are significant modulators of this pathway.


Assuntos
Queratinócitos/efeitos dos fármacos , Ornitina Descarboxilase/biossíntese , Retinoides/farmacologia , Linhagem Celular , Indução Enzimática , Fator de Crescimento Epidérmico/metabolismo , Receptores ErbB/efeitos dos fármacos , Receptores ErbB/metabolismo , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Humanos , Queratinócitos/enzimologia , Queratinócitos/efeitos da radiação , Ornitina Descarboxilase/genética , Ligação Proteica , Raios Ultravioleta
12.
Oncol Res ; 7(9): 445-52, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-8835288

RESUMO

Caffeic acid phenethyl ester (CAPE) was evaluated for its potential in regulating keratinocyte proliferation. CAPE inhibited the proliferation of SV40 transformed keratinocytes (Z114) in a concentration- and time-dependent manner. Inhibition by CAPE was seen with 0.5 to 5.0 micrograms/ml at 48 h. Cell toxicity was observed at 10 micrograms/ml by changes in morphology and decreased viability. Pretreatment of Z114 cells with CAPE significantly prevented the full induction of ornithine decarboxylase (ODC) by epidermal growth factor (EGF) in a concentration- and time-dependent manner. Inhibition was observed with a concentration of CAPE as low as 1 microgram/ml, and complete inhibition of ODC induction by EGF occurred at 5 micrograms/ml. Northern analysis showed that treatment of cells with CAPE for 24 h suppressed EGF induction of ODC gene expression. Incubation of Z114 cells with CAPE for 24 h resulted in a concentration-dependent decrease in EGF binding and a 30% reduction in the EGF induced autophosphorylation of the EGF receptor. CAPE decreased both membranous and cytosolic PKC activity in a concentration- and time-dependent manner. Because significant inhibition of keratinocyte proliferation occurred at concentrations of CAPE that interfered with PKC activity and EGF signal transduction but did not cause overt toxicity, CAPE may prove useful for the treatment of hyperproliferative skin diseases.


Assuntos
Ácidos Cafeicos/toxicidade , Divisão Celular/efeitos dos fármacos , Fator de Crescimento Epidérmico/farmacologia , Queratinócitos/efeitos dos fármacos , Ornitina Descarboxilase/efeitos dos fármacos , Ornitina Descarboxilase/metabolismo , Álcool Feniletílico/análogos & derivados , Sítios de Ligação , Northern Blotting , Western Blotting , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Citosol/enzimologia , Relação Dose-Resposta a Droga , Receptores ErbB/metabolismo , Humanos , Masculino , Ornitina Descarboxilase/biossíntese , Álcool Feniletílico/toxicidade , Proteína Quinase C/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fatores de Tempo
13.
Exp Dermatol ; 2(6): 257-65, 1993 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8162346

RESUMO

We previously demonstrated that epidermal growth factor (EGF) induces a several-fold increase in ornithine decarboxylase (ODC) activity and the steady-state level of ODC mRNA in cultured SV40-transformed human keratinocytes (1). Pretreatment of cell cultures with ultraviolet B (UVB) radiation resulted in a reduction of EGF-induced ODC activity. To determine whether UVB inhibits the accumulation of ODC mRNA by EGF, cells were pretreated with 20 mJ/cm2 UVB or sham-irradiated and then incubated with 100 ng/ml EGF. Northern blot analysis revealed that UVB irradiation entirely blocked the EGF induction of ODC mRNA. Since the binding of EGF to its plasma membrane receptor is the first step in initiating a biological response, the effect of UVB on EGF binding was evaluated. UVB treatment of cultured keratinocytes resulted in an immediate and dose-dependent reduction of EGF binding. Scatchard analysis revealed that the reduction of EGF binding was due to a 52% decrease in the number of available receptors, from 6.2 x 10(4)/cell to 3.0 x 10(4)/cell. However, UVB decreased the EGF-binding affinity very little (Kd = 0.60 nM in control and Kd = 0.75 nM in UVB-treated Z114 cells). In addition, UVB did not alter the rate of EGF internalization. These data suggest that UVB blocks the signal transduction pathway of EGF that is involved in regulation of ODC gene expression. Immunoblot analysis of extracts from irradiated cells showed that UVB induced tyrosine phosphorylation of EGFR and that the quantity of EGFR protein was unaffected by UVB treatment. Phosphorylation of EGFR may be responsible for decreased binding of EGF to its receptor.


Assuntos
Fator de Crescimento Epidérmico/metabolismo , Receptores ErbB/efeitos da radiação , Queratinócitos/efeitos da radiação , Ornitina Descarboxilase/genética , Processamento de Proteína Pós-Traducional/efeitos da radiação , Raios Ultravioleta , Linhagem Celular Transformada , Sobrevivência Celular , Relação Dose-Resposta à Radiação , Endocitose/efeitos da radiação , Indução Enzimática/efeitos dos fármacos , Indução Enzimática/efeitos da radiação , Fator de Crescimento Epidérmico/farmacologia , Receptores ErbB/metabolismo , Humanos , Queratinócitos/enzimologia , Queratinócitos/metabolismo , Ornitina Descarboxilase/biossíntese , Fosforilação/efeitos da radiação , Ligação Proteica/efeitos da radiação , Proteínas Tirosina Quinases/metabolismo , Transdução de Sinais/efeitos da radiação
14.
Int J Dermatol ; 32(9): 656-60, 1993 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8407093

RESUMO

BACKGROUND: The role of anger in the onset or perpetuation of episodes of atopic dermatitis in adults has long been considered an important factor. The objective was to investigate whether atopic patients feel ineffective in dealing with anger and assertiveness when compared with psoriasis patients and control patients. METHODS: Thirty-four adult patients with atopic dermatitis were compared to 28 patients with psoriasis and 32 controls, dental patients without major skin disease. Standard measures of anxiety, anger, assertion, depression, and locus of control as well as a measure of anger effectiveness, designed for this study, were used. RESULTS: There were significant differences between atopic dermatitis patients and controls in that atopics felt angry more readily but were less likely to express it, were more anxious and less assertive, and felt less effective in expressing anger. The only difference between psoriasis patients and controls was less ability to express anger. Atopic patients were more chronically anxious than those with psoriasis. CONCLUSIONS: Adult atopic dermatitis patients are often chronically anxious and feel ineffective in handling anger which suggests that psychological interventions may prove helpful.


Assuntos
Dermatite Atópica/psicologia , Emoções , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Ira , Ansiedade , Assertividade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Psoríase/psicologia , Transtornos Psicofisiológicos
15.
Int J Dermatol ; 32(8): 582-6, 1993 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8407074

RESUMO

BACKGROUND: It has been established that severe psoriasis may lead to nutrient depletion, especially of protein, folate, and iron. Nutrient loss occurs due to the accelerated loss of nutrients from the hyperproliferation and desquamation of the epidermal layer of skin in psoriasis. We have proposed that nutritional support as a secondary form of therapy may be beneficial in aiding some psoriasis patients return to a state of remission. METHODS: To determine how frequently nutritional abnormalities occur in hospitalized psoriasis patients, a retrospective analysis was done of the nutritional status of 50 patients admitted for the treatment of psoriasis. Chart records were analyzed and laboratory data were interpreted in consideration of concurrent medical problems. Protein status and anemia were the primary nutritional indicators studied. RESULTS: We found that of those parameters that may be used as indicators of nutritional status, 18% of the patients had a decreased total protein, 16% of the patients had a decreased serum albumin, 38% had an elevated mean corpuscular volume, and 39% had a decreased hematocrit. CONCLUSIONS: Our findings support the concept that wide-spread psoriasis places the patient at risk to develop minor nutritional abnormalities in protein and folate status even when accounting for confounding medications and coexistent diseases.


Assuntos
Estado Nutricional , Psoríase/sangue , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Proteínas Sanguíneas/análise , Cálcio/sangue , Feminino , Testes Hematológicos , Hospitalização , Humanos , Masculino , Pessoa de Meia-Idade , Valores de Referência , Estudos Retrospectivos
16.
J Invest Dermatol ; 101(1): 54-8, 1993 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8331297

RESUMO

Irradiation of EGF-stimulated human keratinocytes in vitro with ultraviolet B (UVB) radiation inhibited both ornithine decarboxylase (ODC) activity and cellular proliferation. A dose-dependent reduction in ODC activity occurred in primary cultures of adult facial keratinocytes and neonatal foreskin keratinocytes, and in an SV40-transformed keratinocyte cell line derived from neonatal foreskin. When SV40-transformed keratinocytes were treated with epidermal growth factor (EGF), ODC activity was induced up to 21 times in the absence of ultraviolet radiation. However, pre-treatment with UVB significantly reduced the EGF induction of ODC. For example, 85% less ODC activity was observed in cultures treated with EGF (10 ng/ml) plus 2.5 mJ/cm2 of UVB than cultures treated with EGF alone. To assess the effect of UVB on cell proliferation, normal human epidermal keratinocytes grown in medium containing EGF were irradiated with 5 and 10 mJ/cm2 UVB. At days 3 and 5 post-irradiation a significant (up to 78%) decrease in proliferation was observed. Nevertheless, the mean proportion of viable to dead cells remained similar in both UVB-treated and non-irradiated cell cultures. Northern blot analysis of total RNA isolated from irradiated and sham-irradiated cultures showed that UVB caused approximately a one third reduction in steady-state ODC mRNA levels in EGF-stimulated keratinocyte cultures. Because ODC is an enzyme required for cell proliferation, we propose that the UVB-induced decrease in cell proliferation may result at least in part from UVB inhibition of ODC mRNA accumulation and reduced enzyme activity.


Assuntos
Fator de Crescimento Epidérmico/farmacologia , Epiderme/metabolismo , Epiderme/efeitos da radiação , Queratinócitos/metabolismo , Queratinócitos/efeitos da radiação , Inibidores da Ornitina Descarboxilase , Raios Ultravioleta , Divisão Celular/efeitos dos fármacos , Divisão Celular/efeitos da radiação , Células Cultivadas , Células Epidérmicas , Humanos , Queratinócitos/efeitos dos fármacos , Ornitina Descarboxilase/genética , RNA Mensageiro/metabolismo
17.
Exp Dermatol ; 2(3): 125-32, 1993 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8162329

RESUMO

The effect of epidermal growth factor (EGF) on the activity of ornithine decarboxylase (ODC) was evaluated and partially characterized in SV40-transformed, immortalized cultured human keratinocytes. It was observed that the addition of fresh complete medium to confluent cultures resulted in a 10-fold increase in ODC activity. Characterization of this activity using serum-free medium revealed that the increase in ODC activity was primarily due to the presence of EGF (10 ng/ml). A dose-dependent increase in ODC activity was observed when cultures were treated with EGF. Although near maximal induction occurred with EGF concentrations as low as 2.5-10 ng/ml, maximal induction of ODC (25-fold) occurred with an EGF concentration of 50 ng/ml. The peak time for ODC induction was 10 hours following the addition of EGF to keratinocyte cultures. The induction of ODC by EGF was inhibited by pretreatment of cultures with either cycloheximide or actinomycin D, suggesting that both protein synthesis and gene transcription are important in the EGF induction of ODC. EGF significantly increased the steady state levels of ODC mRNA with a peak at 4 hours, preceding the peak in observed enzyme activity as expected. Pretreatment of cultures with retinoic acid (10(-5)-10(-7) M) significantly inhibited the induction of ODC by EGF. Retinoic acid decreased the steady-state levels of ODC mRNA. These data demonstrate that ODC is an enzyme that is induced by EGF in human keratinocytes; this induction probably involves both gene transcription and protein synthesis.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Fator de Crescimento Epidérmico/farmacologia , Queratinócitos/efeitos dos fármacos , Ornitina Descarboxilase/biossíntese , Linhagem Celular Transformada , Meios de Cultura/farmacologia , Meios de Cultura Livres de Soro/farmacologia , Cicloeximida/farmacologia , Dactinomicina/farmacologia , Indução Enzimática/efeitos dos fármacos , Fator de Crescimento Epidérmico/antagonistas & inibidores , Humanos , Queratinócitos/enzimologia , RNA Mensageiro/biossíntese , Vírus 40 dos Símios/fisiologia , Tretinoína/farmacologia
18.
J Am Acad Dermatol ; 26(5 Pt 1): 766-71, 1992 May.
Artigo em Inglês | MEDLINE | ID: mdl-1583179

RESUMO

A national survey was conducted to explore ways in which MD-PhDs in dermatology balance their research and clinical interests and the factors that influenced their career decisions. A questionnaire was mailed to all MD-PhDs who were affiliated with dermatology training programs as determined by a preliminary study. The survey consisted of a questionnaire about research background, career pathway, attitudes about personal and professional issues, and influence of residency training program on career decision making. From 60 MD-PhD dermatologists surveyed, 43 (72%) completed questionnaires. Eighty percent of the respondents (34 of 43) held positions in academic medicine; 76% entered dermatology with the intent to pursue academic medicine. Almost all (93%) held academic positions immediately after residency; 50% held positions with the title of assistant professor or higher as their first postresidency employment. Only 26% of the respondents received funding for their MD-PhD through the federally funded Medical Scientist Training Program. Fifty percent of the respondents completed their training with loans. Despite the long period of training and expense required for the dual career, a high percentage (80%) stayed in academic dermatology suggesting that they are an important source for supplying physician-scientists to the field of dermatology. The ability to limit patient care responsibilities and maintain protected time for research may be a factor responsible for the high percentage of MD-PhDs that stay in academic dermatology.


Assuntos
Dermatologia/educação , Educação de Pós-Graduação em Medicina , Fatores Etários , Dermatologia/economia , Dermatologia/estatística & dados numéricos , Educação de Pós-Graduação em Medicina/economia , Educação de Pós-Graduação em Medicina/estatística & dados numéricos , Características da Família , Bolsas de Estudo/estatística & dados numéricos , Humanos , Internato e Residência/estatística & dados numéricos , Apoio à Pesquisa como Assunto/estatística & dados numéricos , Fatores Sexuais , Inquéritos e Questionários , Estados Unidos
19.
J Am Acad Dermatol ; 26(4): 607-13, 1992 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-1597547

RESUMO

BACKGROUND: Phototherapy for the eyelid has not previously been recognized as a safe and effective treatment of photoresponsive dermatoses of the eyelid, such as atopic dermatitis, vitiligo, psoriasis, lymphomatoid papulosis, and parapsoriasis. OBJECTIVE: The purpose of this study was to demonstrate the efficacy and safety of this treatment. METHODS: Two cases are presented to demonstrate clinical efficacy. In addition, a retrospective eye evaluation of seven patients receiving a combined total of greater than 1300 eyelid phototherapy treatments was performed. To determine whether potentially harmful UV radiation is significantly transmitted through eyelid skin, an in vitro study was conducted to measure the percentage transmittance of ultraviolet-visible radiation through five excised eyelids. RESULTS: In the two cases presented, remarkable improvement occurred without adverse side effects, suggesting that it is possible to deliver incremental UV dosages to eyelid skin to achieve clearing of skin disease. Retrospective analysis of patients' records revealed no ocular disease from the phototherapy. In vitro eyelid examination produced data that indicated negligible quantities of UV radiation were transmitted through eyelid skin compared with the visible spectrum, in which up to 77% of the radiation was transmitted through the tissue. CONCLUSION: The combined clinical experience and transmittance data suggest that eyelid phototherapy is a safe and effective treatment in selected patients.


Assuntos
Dermatite Atópica/radioterapia , Doenças Palpebrais/radioterapia , Pálpebras/efeitos da radiação , Dermatoses Faciais/radioterapia , Terapia Ultravioleta , Vitiligo/radioterapia , Adulto , Dermatite Atópica/tratamento farmacológico , Doenças Palpebrais/tratamento farmacológico , Doenças Palpebrais/patologia , Pálpebras/patologia , Dermatoses Faciais/tratamento farmacológico , Feminino , Humanos , Técnicas In Vitro , Terapia PUVA , Estudos Retrospectivos , Vitiligo/tratamento farmacológico , População Branca
20.
J Invest Dermatol ; 98(2): 125-7, 1992 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-1732378

RESUMO

A survey of all MD-PhD residents in dermatology in the United States was conducted to evaluate the factors important to them in making career pathway decisions. Twenty-six MD-PhDs responded to the survey representing a 90% response rate. Although essentially all entered dermatology with the intention of pursuing a career in academic medicine, 77% percent thought they would be in academic medicine 5 years post-residency. Factors explored for a negative influence on entrance into academic medicine post-residency were 1) financial concerns, 2) length of training, 3) research hiatus due to clinical training, and 4) eligibility for existing funding mechanisms.


Assuntos
Centros Médicos Acadêmicos , Escolha da Profissão , Dermatologia/educação , Adulto , Educação de Pós-Graduação em Medicina , Feminino , Humanos , Internato e Residência , Masculino , Pesquisa/economia , Inquéritos e Questionários , Estados Unidos
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