Repigmentación del pelo canoso tras tratamiento con hormona tiroidea / Repigmentation of gray hair after thyroid hormone treatment

Introducción y objetivos. Basándonos en dos pacientes con oscurecimiento de sus canas que sufrieron una elevación exógena de T3, debida a un coma mixedematoso y a una descompensación de su enfermedad, sugerimos que la hormona tiroidea puede tener un efecto en la homeostasis del folículo piloso. Para ello se utilizan un modelo animal de ratón y un modelo de cultivo in vitro de unidades foliculares, con el objeto de valorar la influencia de la hormona tiroidea en el ciclo capilar. Métodos. Sobre un modelo de ratón estandarizado para el estudio del ciclo capilar (C57BL/6), aplicamos tópicamente T3 (0,5 g) disuelta en etanol una vez al día durante 10 días en el dorso de ratones depilados en fase de telogen. Cultivamos in vitro unidades foliculares, obtenidas de cirugía capilar, con diferentes concentraciones de T3. Resultados. In vivo, al quinto día del tratamiento el 100 % de los ratones estudiados entraron en anagen, mientras que en el grupo control se apreció un inicio del anagen el día 9, que no se completó en todos los ratones hasta el día 15. In vitro, las unidades foliculares tratadas con 100 nM de T3 crecieron de forma significativa respecto al grupo control. Conclusiones. Estos datos sugieren que los folículos en telogen pueden estimularse para entrar en anagen tras la aplicación tópica de T3. Esta hormona puede revertir el encanecimiento del pelo terminal. En cultivo, la administración de T3 estimula el crecimiento del tallo piloso. Los melanocitos foliculares podrían ser la célula diana para estas acciones

Background and objectives. Darkening of gray and white hairs occurred in 2 patients with increased exogenous triiodothyronine (T3) due to treatment of myxedema coma in one case and iatrogenic hyperthyroidism in the other. We hypothesized that thyroid hormone may affect the homeostasis of hair follicles. To test our hypothesis and investigate the influence of thyroid hormone on the hair cycle, we used an in vivo murine model and an in vitro model based on culture of follicular units. Methods.We used the standard C57BL/6 murine model of the hair cycle. T3 (0.5 g) dissolved in ethanol was applied topically once daily for 10 days to a depilated area in the telogen phase on the backs of the mice. Follicular units, obtained from hair transplant interventions, were cultured in vitro with different concentrations of T3. Results. On day 5, all T3-treated mice entered the anagen phase, whereas the anagen phase started spontaneously in control mice on day 9, and not until day 15 had all controls entered this phase. In the in vitro experiment, follicular units treated with 100 nmol/L T3 grew significantly larger compared to the control group. Conclusions. These data suggest that follicles in the telogen phase can be induced to enter the anagen phase by the topical application of T3. This thyroid hormone may reverse graying of the terminal hair. In the in vitro experiments, T3 stimulated hair shaft growth. Follicular melanocytes may be the target cell for these actions

[Repigmentation of gray hair after thyroid hormone treatment]. / Repigmentación del pelo canoso tras tratamiento con hormona tiroidea.

BACKGROUND AND OBJECTIVES: Darkening of gray and white hairs occurred in 2 patients with increased exogenous triiodothyronine (T3) due to treatment of myxedema coma in one case and iatrogenic hyperthyroidism in the other. We hypothesized that thyroid hormone may affect the homeostasis of hair follicles. To test our hypothesis and investigate the influence of thyroid hormone on the hair cycle, we used an in vivo murine model and an in vitro model based on culture of follicular units. METHODS: We used the standard C57BL/6 murine model of the hair cycle. T3 (0.5 microg) dissolved in ethanol was applied topically once daily for 10 days to a depilated area in the telogen phase on the backs of the mice. Follicular units, obtained from hair transplant interventions, were cultured in vitro with different concentrations of T3. RESULTS: On day 5, all T3-treated mice entered the anagen phase, whereas the anagen phase started spontaneously in control mice on day 9, and not until day 15 had all controls entered this phase. In the in vitro experiment, follicular units treated with 100 nmol/L T3 grew significantly larger compared to the control group. CONCLUSIONS: These data suggest that follicles in the telogen phase can be induced to enter the anagen phase by the topical application of T3. This thyroid hormone may reverse graying of the terminal hair. In the in vitro experiments, T3 stimulated hair shaft growth. Follicular melanocytes may be the target cell for these actions.

[Comparative study of the prevalence of hospital infections at a Valencia county hospital]. / Estudio comparativo de la prevalencia de infección hospitalaria en un hospital comarcal valenciano.

BACKGROUND: Nosocomial infections presently imply a 10-day average prolongation of hospital stay per infection, with an important increase in mortality and costs. A comparison is made between the prevalence of nosocomial infections, microorganisms isolated and antimicrobial agents used in the Arnau de Vilanova Hospital (Valencia, Spain), and those corresponding to other hospitals of similar characteristics in the triple-province Valencia Community. METHODS: Cross-sectional epidemiological study, reflecting the prevalence of hospital infections globally and in each of services. RESULTS: The global prevalence of hospital infections was 6.08%. Services with greatest prevalence are Intensive Care, Internal Medicine and Surgery. Respiratory tract and postoperative wound infections were the most frequent presentations. CONCLUSIONS: Global prevalence was slightly less than in the Valencian Community for 1992 (8.28%), with a predominance of gram-negative over gram-positive germs, in contrast with the results reported globally for the Valencia an hospitals.

[Application of DRGs at a regional hospital]. / Aplicación de los GRDs en un hospital comarcal.

BACKGROUND: Of among the different measures systems of hospital production, we adopted the Diagnosis Related Groups (DRG) approach for the management of the cases series of the "Arnau de Vilanova" Hospital (Valencia, Spain). The use of hospital services makes it possible to establish the number of patients attended and in which services, while pathology distribution reflects the types of patients who makes us of the hospital. METHODS: A transverse study was made, reviewing the clinical histories of the hospitalized patients and applying an autoexcluding medical or surgical DRG designation. Patient inspection and comments with the healthcare staff afforded greater specifications. We included all patients hospitalized between May 11 and 24, 1992, i.e., 263 in total, corresponding to 2.53% of the annual hospitalizations in 1992. RESULTS: The most frequently employed services were Internal Medicine and General and Digestive Surgery. Hospital activity was defined by 90 DRGs, the GDRGs most associated to hospital (nosocomial) infection being HIV-positive individuals, those operated on for inguinal hernia, and oncological patients with laryngeal cancer. CONCLUSIONS: Hospital activity was found to be concentrated in high volume DRGs--one of them being the Medical Type "non-groupable diseases due to clinical incompleteness of the management parameters, as a result of which this information remained undetermined.