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1.
Clin Exp Dermatol ; 32(6): 693-5, 2007 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17868391

RESUMEN

Many patients with rosacea are unable to tolerate extended treatment periods with topical agents because of the unusually high skin sensitivity that often accompanies rosacea. Kinetin (N(6)-furfuryladenine) is a plant cytokinin that reportedly helps restore skin barrier function and may be useful to ameliorate the signs and symptoms of rosacea. The purpose of this open-label study was to determine the tolerance and efficacy of twice-daily application of kinetin 0.1% lotion for improving the signs and symptoms of mild to moderate facial rosacea. Subjects applied kinetin 0.1% lotion twice daily to the face, with daily use of a sunscreen of sun protection factor 30. Subjects were evaluated at baseline and at 4-week intervals for 12 weeks to assess efficacy and tolerance. Results of this study suggest that kinetin 0.1% lotion is a well-tolerated moisturizing lotion option for subjects with mild to moderate inflammatory rosacea.


Asunto(s)
Fármacos Dermatológicos/uso terapéutico , Cinetina/uso terapéutico , Rosácea/tratamiento farmacológico , Administración Cutánea , Adulto , Anciano , Fármacos Dermatológicos/efectos adversos , Esquema de Medicación , Emolientes/uso terapéutico , Femenino , Estudios de Seguimiento , Humanos , Cinetina/efectos adversos , Masculino , Persona de Mediana Edad , Rosácea/patología , Índice de Severidad de la Enfermedad , Resultado del Tratamiento
2.
Pharmacol Res ; 53(4): 353-8, 2006 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-16495076

RESUMEN

The 5-HT4 receptor agonist and gastroprokinetic, tegaserod, possesses 5-HT2B receptor antagonist activity. However, the relevance of such activity is unclear. In this study, the 5-HT2B receptor antagonist and 5-HT4 agonist activities of tegaserod were investigated. Two piezoelectric crystals were implanted on the stomach fundus or oesophagus of anaesthetized Sprague-Dawley rats. Measurement of the transmission time of ultrasonic pulses between the implanted crystals provided a continuous record of inter-crystal distance, and thus of muscle length. In the stomach fundus, tegaserod (1 and 3 mg kg(-1)), administered subcutaneously (s.c.), inhibited the contractile response evoked by the 5-HT2B receptor agonist, BW 723C86 (0.01-1 mg kg(-1) intravenously (i.v.)). SB 206553 (1 mg kg(-1) s.c.), a selective 5-HT2B/2C receptor antagonist, also inhibited the BW 723C86-mediated responses. In the rat oesophagus, tegaserod (0.001-0.3 mg kg(-1) i.v. or 0.003-3 mg kg(-1) s.c.) increased inter-crystal distance, consistent with smooth muscle relaxation; the responses were inhibited by the 5-HT4 antagonist, piboserod (0.1 mg kg(-1) s.c.). Data from this in vivo rat study are consistent with tegaserod-induced 5-HT4 receptor-mediated oesophageal relaxation, and antagonism of 5-HT2B receptor-mediated stomach fundus contraction. The clinical relevance of the 5-HT2B receptor antagonism of tegaserod remains to be determined.


Asunto(s)
Indoles/farmacología , Antagonistas del Receptor de Serotonina 5-HT2 , Agonistas del Receptor de Serotonina 5-HT4 , Agonistas de Receptores de Serotonina/farmacología , Animales , Esófago/efectos de los fármacos , Esófago/fisiología , Fundus Gástrico/efectos de los fármacos , Fundus Gástrico/fisiología , Fármacos Gastrointestinales/farmacología , Masculino , Contracción Muscular/efectos de los fármacos , Músculo Liso/efectos de los fármacos , Músculo Liso/fisiología , Ratas , Ratas Sprague-Dawley
3.
Br J Pharmacol ; 143(5): 549-60, 2004 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-15466450

RESUMEN

1 Tegaserod (Zelnorm) is a potent 5-hydroxytryptamine4 (5-HT4) receptor agonist with clinical efficacy in disorders associated with reduced gastrointestinal motility and transit. The present study investigated the interaction of tegaserod with 5-HT2 receptors, and compared its potency in this respect to its 5-HT4 receptor agonist activity. 2 Tegaserod had significant binding affinity for human recombinant 5-HT2A, 5-HT2B and 5-HT2C receptors (pKi=7.5, 8.4 and 7.0, respectively). The 5-HT2B receptor-binding affinity of tegaserod was identical to that at human recombinant 5-HT4(c) receptors (mean pKi=8.4) in human embryonic kidney-293 (HEK-293) cells stably transfected with the human 5-HT4(c) receptor. 3 Tegaserod (0.1-3 microm) inhibited 5-HT-mediated contraction of the rat isolated stomach fundus potently (pA2=8.3), consistent with 5-HT(2B) receptor antagonist activity. Tegaserod produced, with similar potency, an elevation of adenosine 3',5' cyclic monophosphate in HEK-293 cells stably transfected with the human 5-HT4(c) receptor (mean pEC50=8.6), as well as 5-HT4) receptor-mediated relaxation of the rat isolated oesophagus (mean pEC50=8.2) and contraction of the guinea-pig isolated colon (mean pEC50=8.3). 4 Following subcutaneous administration, tegaserod (0.3 or 1 mg kg(-1)) inhibited contractions of the stomach fundus in anaesthetized rats in response to intravenous dosing of alpha-methyl 5-HT (0.03 mg kg(-1)) and BW 723C86 (0.3 mg kg(-1)), selective 5-HT2B receptor agonists. At similar doses, tegaserod (1 and 3 mg kg(-1) subcutaneously) evoked a 5-HT4 receptor-mediated increase in colonic transit in conscious guinea-pigs. 5 The data from this study indicate that tegaserod antagonizes 5-HT2B receptors at concentrations similar to those that activate 5-HT4 receptors. It remains to be determined whether this 5-HT2B receptor antagonist activity of tegaserod contributes to its clinical profile.


Asunto(s)
Indoles/farmacología , Receptor de Serotonina 5-HT2B/efectos de los fármacos , Receptores de Serotonina 5-HT4/efectos de los fármacos , Antagonistas de la Serotonina/farmacología , Agonistas de Receptores de Serotonina/farmacología , Animales , Membrana Celular/efectos de los fármacos , Membrana Celular/metabolismo , Células Cultivadas , Colon/efectos de los fármacos , AMP Cíclico/metabolismo , Esófago/efectos de los fármacos , Fundus Gástrico/efectos de los fármacos , Tránsito Gastrointestinal/efectos de los fármacos , Cobayas , Técnicas In Vitro , Masculino , Contracción Muscular/efectos de los fármacos , Músculo Liso/efectos de los fármacos , Presión , Unión Proteica , Ensayo de Unión Radioligante , Ratas , Ratas Sprague-Dawley
4.
J Am Acad Dermatol ; 45(1): 96-104, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11423841

RESUMEN

BACKGROUND: Aminolevulinic acid hydrochloride (ALA, Levulan) applied topically to actinic keratoses (AKs) leads to accumulation of the photosensitizer protoporphyrin IX, which, when activated by exposure to light, eradicates AKs. OBJECTIVE: We examined the safety and efficacy of photodynamic therapy using topical 20% ALA in a solution formulation and varying blue light doses to treat multiple AKs on the face and scalp. METHOD: This is a multicenter, investigator-blinded, randomized, vehicle-controlled study. RESULTS: Thirty-six patients with clinically typical AKs were treated with 20% ALA; 14 to 18 hours later, they were irradiated with a nonlaser fluorescent blue light source. With the optimal light dose of 10 J/cm(2), 88% of the AKs completely cleared 8 weeks after a single photodynamic treatment, compared with 6% after treatment with vehicle and light. CONCLUSION: Topical ALA PDT using a nonlaser, blue light source is an effective treatment for multiple AKs.


Asunto(s)
Ácido Aminolevulínico/uso terapéutico , Queratosis/tratamiento farmacológico , Fotoquimioterapia , Administración Tópica , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Queratosis/patología , Masculino , Persona de Mediana Edad , Método Simple Ciego , Resultado del Tratamiento
5.
Dermatol Nurs ; 12(6): 385-90; quiz 393-4, 2000 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11912824

RESUMEN

As the aging population increases so does the demand for more effective modalities to combat the ravages of skin aging. It is important for dermatology nurses to understand and be able to explain to patients the preventive measures for skin aging and what can be realistically expected from currently available treatments.


Asunto(s)
Queratolíticos/farmacología , Envejecimiento de la Piel , Tretinoina/farmacología , Cosméticos , Humanos , Piel/patología , Envejecimiento de la Piel/efectos de los fármacos , Protectores Solares
6.
Arch Dermatol ; 133(6): 727-32, 1997 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9197826

RESUMEN

OBJECTIVE: To examine the safety and efficacy of photodynamic therapy using topical 5-aminolevulinic acid (ALA) and red light to treat actinic keratoses (AKs). DESIGN: Actinic keratoses were treated with topical ALA (concentrations of 0%, 10%, 20%, or 30%) under occlusion for 3 hours. Before photodynamic therapy, sites were examined for fluorescence. Sites were irradiated with an argon pumped dye laser (630 nm) at fluences of 10 to 150 J/cm2. SETTING: Academic medical center. PATIENTS: Forty patients with 6 clinically typical, previously untreated AKs per patient. MAIN OUTCOME MEASURE: Complete resolution and decrease in lesion area of the AK relative to baseline evaluated at weeks 1, 4, 8, and 16. RESULTS: Three hours after ALA administration, lesions showed moderate red fluorescence. Cutaneous phototoxic effects, localized erythema and edema, peaked at 72 hours. Patients experienced mild burning and stinging during light exposure. Eight weeks after a single treatment using 30% ALA, there was total clearing of 91% of lesions on the face and scalp and 45% of lesions, on the trunk and extremities. No significant differences were observed in clinical responses with treatment using 10%, 20%, or 30% ALA. All concentrations of ALA were more effective than treating AKs with vehicle and light. CONCLUSIONS: Topical photodynamic therapy with ALA is an effective treatment of typical AKs. Complete clearing of nonhypertrophic AKs can be achieved with 10%, 20%, or 30% ALA that is easily tolerated by the patient. Lesions on the face and scalp are more effectively treated than lesions on the trunk and extremities. Hypertrophic AKs did not respond effectively.


Asunto(s)
Ácido Aminolevulínico/administración & dosificación , Queratosis/tratamiento farmacológico , Fotoquimioterapia , Administración Cutánea , Anciano , Anciano de 80 o más Años , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Queratosis/etiología , Masculino , Persona de Mediana Edad , Proyectos Piloto , Inducción de Remisión , Rayos Ultravioleta/efectos adversos
7.
Gynecol Oncol ; 64(1): 70-5, 1997 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8995550

RESUMEN

OBJECTIVE: To perform a phase I study of topically applied dihematoporphyrin ether (DHE) in the photodynamic treatment (PDT) of cervical intraepithelial neoplasia (CIN) using fixed DHE doses and application schedules, and a variable dose of 630 nm red light delivered by an argon-pumped dye laser. METHODS: Between February 1993 and April 1994, 24 nonpregnant women with a histologic diagnosis of CIN were enrolled. All patients had lesions involving at least 25% of the cervix that were colposcopically visible. Using a cervical cap, 2 ml of a 1% solution of DHE (Photofrin) in a 4% Azone and isopropyl alcohol vehicle were applied to the cervix 24 hr prior to PDT. An argon-pumped dye laser providing light at 630 nm was then used to perform PDT. Light was coupled into a 400-microm silica fiber optic terminating in a microlens which focused the laser radiation onto a circular field of uniform light intensity perpendicular to the tissue. The entire ectocervix was treated in a single field including a margin of 3-5 mm of normal cervix. Using a constant power density (150 mW/cm2) to avoid thermal injury, the PDT energy was increased every 4 patients in a phase I fashion (40, 60, 80, 100, 120, and 140 J/cm2). RESULTS: Thirteen patients with CIN I, 7 patients with CIN II, and 4 patients with CIN III were treated. The maximal energy density was well tolerated. Toxicity was minimal with no patients experiencing local necrosis, sloughing, or scarring; however, a mild vaginal discharge was noted in several patients. Systemic effects were absent. After 12 months of follow-up at 3-month intervals, 22 patients are evaluable of whom 15 (68%) are disease free. One patient was lost to follow-up and in another the cervical cap was dislodged. Four of the 7 failures or recurrences occurred at energy densities of 80 J/cm2 or less, while 8 of 11 (73%) patients were treated successfully with PDT at an energy density of 100 to 140 J/cm2. CONCLUSIONS: PDT with DHE and an argon-pumped dye laser at 630-nm wavelength delivering an energy density of 140 J/cm2 is safe and effective in treating CIN. Phase II studies using PDT at the prescribed application schedule and dose are indicated.


Asunto(s)
Antineoplásicos/uso terapéutico , Éter de Dihematoporfirina/uso terapéutico , Fotoquimioterapia , Displasia del Cuello del Útero/tratamiento farmacológico , Neoplasias del Cuello Uterino/tratamiento farmacológico , Administración Tópica , Femenino , Estudios de Seguimiento , Humanos
8.
Lasers Surg Med ; 21(2): 186-92, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9261796

RESUMEN

BACKGROUND AND OBJECTIVE: The hard and resistant structure of the nail plate forms a natural barrier that limits the penetration of topical drugs. To overcome this barrier, the use of pulsed laser systems has been suggested. The purpose of this study was to evaluate the effect of four laser systems on nail plate ablation rates, ablation efficiencies, and subsequent craters morphology. STUDY DESIGN/MATERIAL AND METHODS: Solid state Er:YAG (2.94 microns, 250 microseconds), a Ho:YSGG (2.08 microns, 250 microseconds), a XeC1 Excimer (308 nm, 15 ns), and a novel solid-state ultrashort pulse laser (1.05 microns, 350 fs) were used. Ablation rates, surface morphology, and extent of collateral damage were evaluated using light and electron microscopy. RESULTS: Best ablation efficiencies were demonstrated with the ultrashort pulsed laser (1 micron/mJ), whereas maximum material removal per pulse was obtained with the Er:YAG laser (80 microns/ pulse). Scanning electron microscopy showed cracking damage with both Ho:YSGG and Er:YAG. XeC1 and the ultrashort pulse system left tissue surfaces free of cracks or thermal damage. CONCLUSION: With its minimal acoustical and mechanical impact, high efficiency, and negligible collateral damage, the ultrashort pulse laser at 3 J/cm2 was found to be the optimal laser system for nail ablation.


Asunto(s)
Terapia por Láser , Uñas/cirugía , Humanos , Técnicas In Vitro , Uñas/ultraestructura
9.
Am J Obstet Gynecol ; 174(3): 951-7, 1996 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-8633675

RESUMEN

OBJECTIVE: Our purpose was to determine the feasibility of selective photosensitization of vulvar condylomas by use of tropical application of 5-aminolevulinic acid. STUDY DESIGN: In vivo fluorescence was assessed and biopsy specimens of condylomas were taken for fluorescence microscopy in 24 patients at different times after application of 2.5% 5-aminolevulinic acid ointment or 20% 5-aminolevulinic acid cream. RESULTS: Both in vivo fluorescence imaging and fluorescence microscopy showed selective fluorescence of condylomas of the labia minora and vestibule only within short time intervals, because fluorescence of poorly keratinized normal epithelium was induced by both 5-aminolevulinic acid formulations. In non-hair-bearing skin, lesional fluorescence remained highly selective. Fluorescence microscopy showed that 90 minutes after drug application peak selectivity in epithelial lesional fluorescence was significantly higher with 2.5% 5-aminolevulinic acid ointment (4.5 +/- 0.9) than it was with 20% cream (2.1 +/- 0.2). CONCLUSION: Selective fluorescence of vulvar condyloma acuminatum can be induced by nonselective topical 5-aminolevulinic acid application. Studies evaluating selective photodynamic destruction of condylomas are justified.


Asunto(s)
Ácido Aminolevulínico/farmacocinética , Condiloma Acuminado/tratamiento farmacológico , Fármacos Fotosensibilizantes/farmacología , Enfermedades de la Vulva/tratamiento farmacológico , Administración Tópica , Adulto , Ácido Aminolevulínico/administración & dosificación , Ácido Aminolevulínico/uso terapéutico , Condiloma Acuminado/metabolismo , Estudios de Factibilidad , Femenino , Humanos , Microscopía Fluorescente , Pomadas , Fotoquimioterapia , Fármacos Fotosensibilizantes/administración & dosificación , Fármacos Fotosensibilizantes/uso terapéutico , Distribución Tisular , Enfermedades de la Vulva/metabolismo
10.
J Invest Dermatol ; 105(6): 733-8, 1995 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-7490464

RESUMEN

Although psoriasis is characterized by the accumulation of activated proliferating lymphoid cells in the psoriatic skin lesion, it is not known whether these cells are activated and proliferating before entry into the psoriatic plaque. The current study evaluates the number and phenotype of proliferating lymphoid cells in the blood of psoriatic patients. Proliferation of peripheral blood mononuclear cells was evaluated on cytospun preparations of these cells using autoradiographic techniques after pulsing the mononuclear cells with 3H-methyl thymidine for 2 h. The phenotypes of the labeled peripheral blood mononuclear cells were determined combining autoradiography and immunohistochemistry with monoclonal antibodies directed at CD3, CD4, CD8, CD11c, CD22, and human leukocyte antigen-DR. The data demonstrated elevated numbers of proliferating lymphoid cells in the blood of psoriatic patients compared with normal nonpsoriatic volunteers (p < 0.01). Furthermore, the number of circulating proliferating mononuclear cells increased significantly with increasing psoriasis skin disease severity (correlation coefficient 0.95; p < 0.0001). When the phenotype of the proliferating cells in the blood was examined, the numbers of T cells (CD3+, CD4+, CD8+ cells), B cells (CD22+ cells), monocytes (CD11c+ cells), and human leukocyte antigen-DR+ cells were significantly elevated compared with nonpsoriatic skin (p < 0.01) and increased with increasing disease activity (correlation coefficient range 0.48-0.74; p < 0.05). The data suggest a generalized systemic activation of T, B, and monocytic cells that results in labeling of up to 0.16% of the circulating mononuclear cells with 3H-methyl thymidine (i.e., proliferating and presumably activated) when assayed in vitro.


Asunto(s)
Leucocitos Mononucleares/fisiología , Psoriasis/sangre , División Celular , Antígenos HLA-DR/análisis , Humanos , Recuento de Leucocitos , Metotrexato/farmacología , Fenotipo , Psoriasis/patología
11.
Cutis ; 55(5): 306-10, 1995 May.
Artículo en Inglés | MEDLINE | ID: mdl-7614843

RESUMEN

Topical therapy is the major treatment approach for patients with psoriasis. However, the effectiveness of available drugs (response rates and long-term maintenance) is not well known. This study investigated the current perceptions of American dermatologists on the effectiveness of topical medications for patients with mild or limited psoriasis. In a survey of 225 American dermatologists, class I to II topical steroids were regarded as most effective: 29 percent of dermatologists expected most of their patients to experience clearing of lesions when treated with these agents. Much lower response rates were found with medium and low-potency steroids, anthralin, or tars. The percentage of patients whose skin remained clear of lesions decreased to 50 percent while receiving maintenance corticosteroid therapy by three months and to 29 percent after one year. Topical corticosteroids were considered less effective than the available photo/systemic therapies by 79 percent of physicians. More effective topical modalities need to be developed to treat patients with mild/limited psoriasis.


Asunto(s)
Antiinflamatorios/uso terapéutico , Psoriasis/tratamiento farmacológico , Administración Tópica , Glucocorticoides , Humanos , Encuestas y Cuestionarios , Resultado del Tratamiento
12.
J Invest Dermatol ; 104(2): 183-8, 1995 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-7829873

RESUMEN

Although methotrexate (MTX) is one of the most clinically effective therapies employed to treat psoriasis, the mechanism by which low-dose MTX acts to modulate the hyperplasia of psoriasis, leading to the restoration of clinically normal skin, is only partially understood. MTX has been considered a cytotoxic agent that mediates its effect primarily on proliferating or cycling epidermal cells. Recently, proliferating lymphoid cells have been identified in psoriatic lesions, raising the possibility that proliferating lymphoid cells could be another target cell that is killed by MTX. In this study, we examined the growth-inhibitory and cytotoxic effects of MTX on proliferating lymphoid cells [THP-1 (macrophage), and MOLT-4 (T cell)], epithelial cells (HeLa, and HaCat), and normal human keratinocytes (NHK) in vitro. The proliferating cells were exposed to MTX for 24 h, and placed in fresh media to mimic the transient MTX blood levels that result from once-weekly therapy. THP-1 and MOLT-4 were found to be 10-100 times more sensitive to the cytotoxic effects of MTX than were HeLa and HaCat, and more than 1000 times more sensitive than primary human keratinocytes. At MTX concentrations that would be expected to occur in vivo during once-weekly therapy, a large percentage (> 95%) of proliferating lymphoid targets would be killed, and only a small percentage (< 10%) of proliferating epidermal cells would be affected. This in vitro data suggests that in psoriasis proliferating lymphoid cells are more likely than epithelial cells to be a major cellular target of MTX in vivo.


Asunto(s)
Tejido Linfoide/citología , Metotrexato/uso terapéutico , Psoriasis/tratamiento farmacológico , Piel/citología , División Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Células Clonales , Relación Dosis-Respuesta a Droga , Células Epiteliales , Epitelio/efectos de los fármacos , Células HeLa/efectos de los fármacos , Humanos , Queratinocitos/efectos de los fármacos , Macrófagos/citología , Metotrexato/administración & dosificación
13.
Int J Dermatol ; 30(12): 860-3, 1991 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-1816129

RESUMEN

The immunofluorescent staining patterns of three differentiation-specific monoclonals (HLK3, HLK7, HLK20) that display different immunofluorescent (IF) reactivity in normal and psoriatic epidermis, were examined in basal cell carcinoma (BCC) and squamous cell carcinoma (SCC), as well as other human normal epithelial and nonepithelial tissues. Similar staining patterns within epidermis were seen with HLK3 (intercellular) and HLK7 (perinuclear) in psoriasis, SCC, and BCC. HLK20 selectively stained BCC and SCC within epidermis and dermis, and was negative in psoriasis. The monoclonals did not react with nonepithelial tissues, but repetitively displayed positive, granular reactivity with simple epithelia and transitional epithelium. Stratified squamous epithelia showed IF staining similar to normal epidermis for all three monoclonals. These new monoclonal antibodies offer new investigative tools to study abnormalities in keratinocyte differentiation in benign and malignant hyperplastic skin diseases.


Asunto(s)
Anticuerpos Monoclonales , Queratinocitos/inmunología , Neoplasias Cutáneas/patología , Carcinoma Basocelular/patología , Carcinoma de Células Escamosas/patología , Técnica del Anticuerpo Fluorescente , Células HeLa , Humanos , Psoriasis/patología , Sensibilidad y Especificidad
14.
J Invest Dermatol ; 97(5): 874-9, 1991 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-1919050

RESUMEN

The precise removal of stratum corneum from cadaveric swine skin by a mid-infrared erbium:yttrium scandium gallium garnet laser (lambda = 2.79 microns; 250 microseconds pulse width) was assessed by electrical resistance measurements and documented by histology. The effects of stratum corneum removal by laser ablation and by adhesive tape-stripping on the in vitro penetration of 3H-hydrocortisone and 125I-gamma-interferon were determined. Excised swine skin was irradiated with laser (1 J/cm2; 31 mJ/pulse; 1 Hz; 2 mm spot diameter). For skin penetration studies, laser pulses were delivered to discrete 2-mm areas to ablate up to 12.6% of the total 3-cm2 stratum corneum diffusional area. Franz in vitro skin penetration chambers were used to measure the cumulative 48-h penetration of 3H-hydrocortisone and 125I-gamma-interferon in laser-treated and tape-stripped skin. Electrical resistance measurements and histologic studies demonstrated that 10-14 laser pulses at the above energy density were required to abolish skin resistance and selectively ablate stratum corneum without damage to adjacent dermal structures. Laser ablation of 12.6% of the surface area of stratum corneum produced a 2.8 and 2.1-times increase in permeability constant (kp) for 3H-hydrocortisone and 125I-gamma-interferon, respectively. These studies demonstrate that a pulsed mid-infrared laser can reliably and precisely remove the stratum corneum, facilitating penetration of large molecules such as 125I-gamma-interferon that cannot penetrate intact skin. This new technique may be useful for basic and clinical investigation of skin barrier properties.


Asunto(s)
Procedimientos Quirúrgicos Dermatologicos , Hidrocortisona/farmacocinética , Interferón gamma/farmacocinética , Terapia por Láser/métodos , Administración Cutánea , Animales , Transporte Biológico , Hidrocortisona/administración & dosificación , Rayos Infrarrojos , Interferón gamma/administración & dosificación , Radioisótopos de Yodo , Porcinos , Tritio
15.
Plast Reconstr Surg ; 87(3): 529-35, 1991 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-1998022

RESUMEN

Using vein grafts to bypass sclerotic and occluded arterial segments is a well-established technique in vascular surgery. For infrapopliteal bypass, autogenous veins have better patency rates than synthetic grafts. Although not resolved, in situ bypasses seem to be better than reversed bypasses, especially for "far away" segments. Although the etiology is not understood, it is a well-known clinical finding that sclerosis affects arteries more than the veins and, as a whole, is more advanced in lower extremities compared with the trunk and upper extremities. Our experience with eight patients in whom critical soft-tissue defects were covered with free-tissue transfers in severely compromised lower extremities utilizing the in situ saphenous vein bypass as the inflow is presented. Simultaneous bypass and free-tissue transfers were performed in seven and delayed free-tissue transfer was done in one. Follow-up ranged from 6 months to 3 years. To date, two patients underwent amputations. Five patients are able to maintain bipedal ambulation. One patient is wheelchair-bound with intact lower extremities. In well-selected patients, this procedure may offer an alternative treatment to amputation. However, because of the complexity of these combined procedures, we strongly urge careful patient selection.


Asunto(s)
Enfermedades del Pie/cirugía , Úlcera de la Pierna/cirugía , Pierna/cirugía , Vena Safena/trasplante , Colgajos Quirúrgicos/métodos , Adulto , Anciano , Femenino , Humanos , Isquemia/complicaciones , Pierna/irrigación sanguínea , Úlcera de la Pierna/etiología , Masculino , Persona de Mediana Edad , Úlcera Cutánea/cirugía , Grado de Desobstrucción Vascular
16.
J Invest Dermatol ; 95(5 Suppl): 49S-52S, 1990 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-16788633

RESUMEN

Based on recent experience that Cyclosporin A, an immunosuppressive drug, produces marked improvement in psoriasis, possible immunomodulatory activities of methotrexate (MTX) have been reviewed to look for alternate mechanisms of MTX action in psoriasis. It is generally considered that the therapeutic results of MTX in psoriasis are related to a direct effect on epidermal cell hyperplasia through inhibition of DNA synthesis. Several studies in the literature now suggest possible effects of MTX on the immune system of psoriatics as well as in animal models that may have some pathogenic similarities to psoriasis. In psoriatics receiving MTX, neutrophil chemotaxis is suppressed, resulting in a possible alteration in the potential pathologic activity of neutrophils commonly found in lesional skin. MTX does improve both psoriatic and rheumatoid arthritis. Animal studies of the latter using adjuvant arthritis and graft vs host disease (GVHD) have indicated several possible mechanisms for MTX that affect these processes. In GVHD, MTX selectively destroys cycling CD8+ cells, and in adjuvant arthritis the activation of macrophages is prevented by inhibition of T-cell function. While MTX generally has not been clinically utilized as an immunomodulatory drug for immunologically related diseases, it may, nonetheless, have selective actions that could be specific for some diseases. MTX and Cyclosporin A could work mechanistically in similar ways but at different steps in the activation of T cells and macrophages. It may be that the major direct effect of MTX on epidermal cell proliferation is complemented or even mediated by subtle immunoregulatory effects on the melange of cells in the affected skin and the systemic immune response.


Asunto(s)
Sistema Inmunológico/efectos de los fármacos , Metotrexato/farmacología , Psoriasis/tratamiento farmacológico , Animales , Artritis Experimental/tratamiento farmacológico , Artritis Reumatoide/tratamiento farmacológico , Proliferación Celular/efectos de los fármacos , ADN/biosíntesis , Células Epidérmicas , Epidermis/efectos de los fármacos , Enfermedad Injerto contra Huésped/tratamiento farmacológico , Humanos , Metotrexato/uso terapéutico , Ratones
17.
J Vasc Surg ; 9(5): 718-23; discussion 723-4, 1989 May.
Artículo en Inglés | MEDLINE | ID: mdl-2566694

RESUMEN

Occlusive lesions of the innominate artery that require operation occur infrequently. Direct repair has been performed with low morbidity and mortality. There is debate over the best method of direct reconstruction. Twenty-six patients undergoing transsternal innominate artery repair over a 12-year period were reviewed to determine if either grafting or endarterectomy was superior and what technical factors might be responsible for success or failure. Most of the patients were women. Twenty-four of the patients had atherosclerotic lesions, whereas the other two had Takayasu's arteritis. Either neurologic or right upper extremity symptoms were present in 24 patients. Sixteen patients had grafting, and 10 underwent endarterectomy. There was one death. There were no strokes or transient ischemic attacks. Three patients experienced recurrence of their symptoms; all had failures of reconstruction. The use of a bifurcated graft in one patient was probably responsible for one recurrence of symptoms. Single limb grafts with added side arms are probably preferable to bifurcated grafts. Innominate artery grafting and innominate endarterectomy are equally effective, although grafting is applicable to more patients. Direct transsternal repair is the procedure of choice to correct innominate occlusive disease in patients who are good candidates for correction.


Asunto(s)
Aorta Torácica/cirugía , Tronco Braquiocefálico/cirugía , Endarterectomía , Adulto , Anciano , Anastomosis Quirúrgica/métodos , Arteriopatías Oclusivas/diagnóstico por imagen , Arteriopatías Oclusivas/cirugía , Arteriosclerosis/diagnóstico por imagen , Arteriosclerosis/cirugía , Tronco Braquiocefálico/diagnóstico por imagen , Estudios de Evaluación como Asunto , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Radiografía , Recurrencia , Arteritis de Takayasu/diagnóstico por imagen , Arteritis de Takayasu/cirugía
18.
Photochem Photobiol ; 49(4): 431-8, 1989 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-2727082

RESUMEN

The major side effect associated with porphyrins (Photofrin II) in clinical photodynamic therapy is skin photosensitivity. In order to avoid this deleterious reaction, patients must remain out of the sunlight for approximately 1 month. A possible procedure to reduce the amount of skin photosensitivity is to photodegrade (photobleach) the compound in the skin. In this study, we report a series of experiments describing the photodegradation rates of two photosensitizers currently receiving attention due to their potential for use in PDT (mono L-aspartyl chlorin e6 and chloroaluminum sulfonated phthalocyanine). These compounds are compared to Photofrin II (PfII). Experiments consisted of determining photodegradation rates and efficiencies of the sensitizers in (i) phosphate buffered saline (PBS), (ii) PBS with fetal calf serum (to enhance absorption and simulate cellular binding or deaggregation), (iii) Chinese Hamster Ovary cells, and (iv) Balb/c mice. We performed two standardized skin sensitivity assays using the Hartely albino guinea pig irradiated with a UV blue point lamp and Balb/c mice irradiated with the therapeutic wavelength of each sensitizer. In addition, we performed a cell clonogenicity assay comparing photodegraded and fresh PfII on CHO cells. The photodegraded PfII exhibited significant phototoxicity, although the fluorescence was bleached by more than 70%. The results show that PfII causes major skin photosensitization and that the other compounds produce no substantial skin sensitivity. Our studies suggest that photodegradation of PfII with 630 nm light has little influence on the phototoxicity of the compound. In addition, skin sensitivity was not alleviated with prior photobleaching with 405 nm light.


Asunto(s)
Fotoquimioterapia/efectos adversos , Trastornos por Fotosensibilidad/etiología , Porfirinas/metabolismo , Animales , Cricetinae , Fluorescencia , Cobayas , Masculino , Ratones , Ratones Endogámicos BALB C , Protectores Solares
19.
Arch Dermatol ; 125(2): 227-30, 1989 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-2913960

RESUMEN

In vitro percutaneous penetration of methotrexate is enhanced with 1-dodecylazacycloheptan-2-one (laurocapram [Azone]). Laurocapram-containing methotrexate formulations provide effective local inhibition of epidermal DNA synthesis in the in vivo hairless mouse and minipig models, providing the biochemical rationale for topical use in the treatment of psoriasis. Topical methotrexate (0.1%, 0.5%, and 1%) in a laurocapram-containing formulation was tested in a two-center double-blind pilot clinical study of 42 patients with plaque psoriasis. Drugs were applied twice a day for six weeks, and lesions were scored weekly for erythema, scale, and elevation. An overall improvement of 50% or more in the combined scores for erythema, scale, and elevation was obtained with 0.1% methotrexate (64% of patients), 0.5% methotrexate (59%), and 1% methotrexate (56%) vs the vehicle alone (25%). These preliminary findings suggest that methotrexate preparations that provide adequate percutaneous absorption may have a beneficial effect in the treatment of psoriasis.


Asunto(s)
Metotrexato/uso terapéutico , Psoriasis/tratamiento farmacológico , Administración Tópica , Azepinas/administración & dosificación , Azepinas/uso terapéutico , ADN/biosíntesis , Humanos , Metotrexato/administración & dosificación , Vehículos Farmacéuticos , Distribución Aleatoria , Factores de Tiempo
20.
Contact Dermatitis ; 20(1): 10-6, 1989 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-2914430

RESUMEN

Cyclosporine (CSA) is an effective immunosuppressive agent and is used in tissue transplantation. The present investigation was undertaken to determine the effect of topical delivery of CSA on allergic contact dermatitis in guinea pigs. Topical 15% CSA in an azone (1-dodecylazacycloheptan-2-one)-containing vehicle blocked local elicitation in previously dinitrochlorobenzene (DNCB) sensitized animals that received a single topical application just prior to elicitation. Elicitation was not blocked at a distant site, indicating a local effect of topical CSA. In contrast, topical CSA when applied twice daily for a total of 5 applications during sensitization only, did not block subsequent elicitation. These experiments suggest that cyclosporine may be beneficial in the therapy of human contact dermatitis, as well as other T cell mediated dermatoses.


Asunto(s)
Ciclosporinas/administración & dosificación , Dermatitis por Contacto/tratamiento farmacológico , Administración Tópica , Animales , Biopsia , Ciclosporinas/uso terapéutico , Dermatitis por Contacto/patología , Cobayas
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