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1.
Clin Immunol ; 193: 33-37, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29395846

RESUMEN

Acute graft-versus-host disease (aGVHD) complicates allogeneic hematopoietic stem cell transplantation (HSCT), and is treated with topical and/or systemic corticosteroids. Systemic corticosteroids and aGVHD damage thymic tissue. We compared thymopoietic effect of topical steroid therapy, corticosteroids and extracorporeal photopheresis (ECP) in 102 pediatric allogeneic HSCT patients. We categorized patients into 4 groups: - no aGVHD, aGVHD treated with topical or systemic steroid, or ECP. Naïve CD4+CD45RA+CD27+ T-lymphocyte values at 3, 6, 9, 12months post-HSCT were recorded: for ECP patients, values were recorded at 3, 6, 9, 12months during ECP. Differences were compared using the Kruskal-Wallis test. 41 patients had no aGVHD, 23 had aGVHD treated topically or systemically (25), 13 received ECP. Rate of thymopoiesis was significantly different between all groups at all time-points post-transplant (p=0.002, p<0.001, p<0.001, p=0.001 respectively). Even mild aGVHD impairs thymopoiesis. Worst recovery was in ECP patients. Earlier institution of ECP may speed thymic recovery.


Asunto(s)
Corticoesteroides/uso terapéutico , Linfocitos T CD4-Positivos/inmunología , Enfermedad Injerto contra Huésped/inmunología , Trasplante de Células Madre Hematopoyéticas , Inmunosupresores/uso terapéutico , Timo/inmunología , Enfermedad Aguda , Niño , Preescolar , Estudios de Cohortes , Femenino , Enfermedad Injerto contra Huésped/tratamiento farmacológico , Hematopoyesis , Humanos , Lactante , Antígenos Comunes de Leucocito/metabolismo , Masculino , Fotoféresis , Estudios Retrospectivos , Trasplante Homólogo , Miembro 7 de la Superfamilia de Receptores de Factores de Necrosis Tumoral/metabolismo
2.
Qual Life Res ; 27(9): 2373-2382, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29948600

RESUMEN

PURPOSE: To determine the changes in each of the five dimensions of the EuroQol 5-dimension index associated with community-based physiotherapy. METHODS: Four thousand one hundred and thirty-six patients that received community-based musculoskeletal physiotherapy across five NHS centres completed the EQ-5D on entry into the service and upon discharge. Patients were categorised on symptom location and response to treatment based on their EQ-5D index improving by at least 0.1 ("EQ-5D responders"). For each symptom location, and for responders and non-responders to treatment, the mean (± SD) were calculated for each dimension pre- and post-treatment as well as the size of effect. RESULTS: The mobility dimension improved (p < 0.05) in all symptom locations for EQ-5D responders (d = 0.26-1.58) and in ankle, knee, hip and lumbar symptoms for EQ-5D non-responders (d = 0.17-0.45). The self-care dimension improved (p < 0.05) in all symptom locations for EQ-5D responders (d = 0.49-1.16). The usual activities dimension improved (p < 0.05) across all symptom locations for EQ-5D responders (d = 1.00-1.75) and EQ-5D non-responders (d = 0.14-0.60). Despite the pain/discomfort dimension improving (p < 0.05) across all symptom locations for both EQ-5D responders (d = 1.07-1.43) and EQ-5D non-responders (d = 0.29-0.66), the anxiety/depression dimension improved (p < 0.05) from higher starting levels in EQ-5D responders (d = 0.76-1.05) with no change seen for EQ-5D non-responders (d = - 0.16 to 0.06). CONCLUSIONS: Clinicians should not assume that a patient presenting with pain but expressing high anxiety/depression is unlikely to respond to treatment, as they may show the best HRQoL outcomes. For patients presenting with pain/discomfort and low levels of anxiety/depression, the EQ-5D index is perhaps not a suitable tool for sole use in patient management and service evaluation.


Asunto(s)
Modalidades de Fisioterapia/psicología , Calidad de Vida/psicología , Femenino , Humanos , Masculino , Encuestas y Cuestionarios
3.
Health Qual Life Outcomes ; 15(1): 212, 2017 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-29065895

RESUMEN

BACKGROUND: Community-based musculoskeletal physiotherapy is used to improve function and health related quality of life (HRQoL). The purpose of this retrospective, multi-centre observational study was to determine the association between community-based physiotherapy management for musculoskeletal disorders and changes in HRQoL. METHODS: Four thousand one hundred twelve patients' data were included in the study. Patients were included if they received a single period of treatment for a musculoskeletal injury or disorder. Patients were only included if they were being treated for a single morbidity. Patients received standard physiotherapy appropriate to their specific disorder, which could include health education/advice, exercise therapy, manual therapy, taping, soft tissue techniques, electrotherapy and/or acupuncture. Health related quality of life was assessed using the EQ-5D index. RESULTS: EQ-5D improved by 0.203 across all patients (d = 1.10). When grouped by anatomical site of symptom, the largest increases in EQ-5D was in foot pain (0.233; d = 1.29) and lumbar pain (0.231; d = 1.13). Improvements in EQ-5D greater than the minimum clinically important difference (MCID) were seen in 68.4% of all patients. The highest proportion of patients with positive responses to treatment were in ankle pain (74.2%) and thoracic pain (73.4%). The hand (40.5%), elbow (34.7%), and hip (33.9%) showed the greatest proportion of patients that did not respond to treatment. CONCLUSIONS: Community-based musculoskeletal physiotherapy is associated with improved health related quality of life. A randomised controlled trial is needed to determine any causal relationship between community-based physiotherapy and health related quality of life improvements.


Asunto(s)
Enfermedades Musculoesqueléticas/psicología , Enfermedades Musculoesqueléticas/rehabilitación , Sistema Musculoesquelético/lesiones , Modalidades de Fisioterapia , Calidad de Vida , Adulto , Servicios de Salud Comunitaria , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Encuestas y Cuestionarios
4.
An Acad Bras Cienc ; 87(2 Suppl): 1397-408, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26247152

RESUMEN

Several studies have investigated the antinociceptive, immunomodulatory and anti-inflammatory properties of compounds found in the lavender essential oil (LEO), however to date, there is still lack of substantial data. The objective of this study was to assess the antioxidant, anti-inflammatory and antinociceptive effects of lavender essential oil. The 1,1-diphenyl-2-picrylhydrazyl radical decolorization assay was used for antioxidant activity evaluation. The anti-inflammatory activity was tested using two models of acute inflammation: carrageenan-induced pleurisy and croton oil-induced ear edema. The antinociceptive activity was tested using the pain model induced by formalin. LEO has antioxidant activity, which is dose-dependent response. The inflammatory response evoked by carrageenan and by croton oil was reduced through the pre-treatment of animals with LEO. In the pleurisy model, the drug used as positive control, dexamethasone, was more efficacious. However, in the ear swelling, the antiedematogenic effect of the oil was similar to that observed for dexamethasone. In the formalin test, LEO consistently inhibited spontaneous nociception and presented a similar effect to that of tramadol. The results of this study reveal (in vivo) the analgesic and anti-inflammatory activities of LEO and demonstrates its important therapeutic potential.


Asunto(s)
Analgésicos/uso terapéutico , Antiinflamatorios/uso terapéutico , Antioxidantes/uso terapéutico , Edema/tratamiento farmacológico , Aceites Volátiles/uso terapéutico , Dolor/tratamiento farmacológico , Aceites de Plantas/uso terapéutico , Analgésicos/aislamiento & purificación , Animales , Antiinflamatorios/aislamiento & purificación , Antioxidantes/aislamiento & purificación , Carragenina , Aceite de Crotón , Modelos Animales de Enfermedad , Edema/inducido químicamente , Femenino , Lavandula , Dolor/inducido químicamente , Dimensión del Dolor , Ratas , Ratas Wistar
5.
Molecules ; 17(1): 1113-23, 2012 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-22269829

RESUMEN

Baccharis trimera is a plant popularly used as a tea and to treat gastrointestinal diseases and inflammatory processes as well. The total phenolic content was determined and the antioxidant and anti-inflammatory activities of six extracts (dichloromethane, ethyl acetate, butanol, aqueous, saponin and phenolic) from B. trimera were evaluated. Using carrageenan-induced pleurisy as a model of acute inflammation, the phenolic extract at 15 mg/kg decreased significantly the analyzed parameters when compared to the carrageenan group ( p < 0.05), thus showing potential anti-inflammatory activity. The total phenolic content and antioxidant activity were evaluated by the Folin-Ciocalteau and DPPH methods, respectively. Phenolic and ethyl acetate extracts presented higher antioxidant activity ( p < 0.05) than ascorbic acid. The phenolic extract also showed the highest antioxidant potential in relation to the other extracts, thus suggesting that the antioxidant and anti-inflammatory activities were due to the presence of phenolic compounds.


Asunto(s)
Antiinflamatorios/farmacología , Antioxidantes/farmacología , Baccharis/química , Fenoles/química , Extractos Vegetales/farmacología , Animales , Ácido Ascórbico/metabolismo , Compuestos de Bifenilo/metabolismo , Carragenina , Femenino , Concentración 50 Inhibidora , Óxido Nítrico/metabolismo , Picratos/metabolismo , Hojas de la Planta/química , Pleuresia/patología , Ratas , Ratas Wistar
6.
Artículo en Inglés | MEDLINE | ID: mdl-17693069

RESUMEN

Previous studies suggest that consuming meals containing large amounts of fish oil is associated with selective postprandial incorporation of 20:5n-3 and 22:6n-3 into plasma non-esterified fatty acids (NEFA). We investigated the effect of consuming meals containing different amounts of 20:5n-3 and 22:6n-3 comparable to dietary habits of western populations on the postprandial incorporation of 18:3n-3, 20:5n-3 and 22:6n-3 into plasma triacylglycerol (TAG) and NEFA over 6h in middle aged subjects. 20:5n-3 incorporation into plasma TAG was greater than 22:6n-3 irrespective of the test meal. Conversely, 22:6n-3 incorporation into plasma NEFA was greater than 20:5n-3, irrespective of the test meal. There was no effect of the amount of 20:5n-3+22:6n-3 in the test meal on the 18:3n-3 incorporation into plasma TAG or NEFA. These findings suggest differential metabolism of 20:5n-3 and 22:6n-3 in the postprandial period when consumed in amounts typical of western dietary habits.


Asunto(s)
Ácidos Docosahexaenoicos/administración & dosificación , Ácido Eicosapentaenoico/administración & dosificación , Ácidos Grasos no Esterificados/sangre , Periodo Posprandial/fisiología , Triglicéridos/sangre , Anciano , Ácidos Docosahexaenoicos/análisis , Ácido Eicosapentaenoico/análisis , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores Sexuales , Factores de Tiempo
7.
Mol Cell Biol ; 22(15): 5419-33, 2002 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12101236

RESUMEN

The caspase 8 inhibitor c-FLIP(L) can act in vitro as a molecular switch between cell death and growth signals transmitted by the death receptor Fas (CD95). To elucidate its function in vivo, transgenic mice were generated that overexpress c-FLIP(L) in the T-cell compartment (c-FLIP(L) Tg mice). As anticipated, FasL-induced apoptosis was inhibited in T cells from the c-FLIP(L) Tg mice. In contrast, activation-induced cell death of T cells in c-FLIP(L) Tg mice was unaffected, suggesting that this deletion process can proceed in the absence of active caspase 8. Accordingly, c-FLIP(L) Tg mice differed from Fas-deficient mice by showing no accumulation of B220(+) CD4(-) CD8(-) T cells. However, stimulation of T lymphocytes with suboptimal doses of anti-CD3 or antigen revealed increased proliferative responses in T cells from c-FLIP(L) Tg mice. Thus, a major role of c-FLIP(L) in vivo is the modulation of T-cell proliferation by decreasing the T-cell receptor signaling threshold.


Asunto(s)
Proteínas Portadoras/metabolismo , Inhibidores de Caspasas , Inhibidores Enzimáticos/metabolismo , Péptidos y Proteínas de Señalización Intracelular , Receptores de Antígenos de Linfocitos T/metabolismo , Linfocitos T/metabolismo , Animales , Apoptosis/efectos de los fármacos , Proteína Reguladora de Apoptosis Similar a CASP8 y FADD , Complejo CD3/farmacología , Antígenos CD4/biosíntesis , Antígenos CD8/biosíntesis , Proteínas Portadoras/genética , Proteínas Portadoras/farmacología , Caspasa 8 , Caspasa 9 , Caspasas/metabolismo , División Celular/efectos de los fármacos , División Celular/fisiología , Células Cultivadas , Inhibidores Enzimáticos/farmacología , Proteína Ligando Fas , Citometría de Flujo , Humanos , Interleucina-2/biosíntesis , Antígenos Comunes de Leucocito/metabolismo , Activación de Linfocitos/efectos de los fármacos , Activación de Linfocitos/fisiología , Sustancias Macromoleculares , Glicoproteínas de Membrana/farmacología , Ratones , Ratones Endogámicos , Ratones Transgénicos , Isoformas de Proteínas/metabolismo , Isoformas de Proteínas/farmacología , Linfocitos T/citología , Linfocitos T/efectos de los fármacos
8.
Arch Intern Med ; 145(6): 1083-8, 1985 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-3890789

RESUMEN

During a multicenter prospective randomized trial in febrile neutropenic patients (neutrophil count, less than 1,000/cu mm), 103 episodes were treated with tobramycin sulfate plus ticarcillin disodium (TT) while 117 were treated with moxalactam plus ticarcillin disodium (MT). The majority of patients had an underlying diagnosis of leukemia (60%) and most (62.8%) had granulocyte counts of less than 100/cu mm at the start of therapy. The response rates for clinically or microbiologically documented episodes were 38 of 60 (55.1%) for TT and 38 of 64 (59.4%) for MT. The MT regimen appeared to be more effective for gram-positive infections (56% vs 33%) while TT appeared more effective for gram-negative infections (64% vs 40%). Nephrotoxicity attributable to study drugs occurred in only 2.3% of cases (one on each treatment arm). Prolongation of the prothrombin time was observed in only six of 78 (7.7%) in the TT arm as compared with 39 of 103 (38%) in the MT arm. Neither regimen was adequate for the unusually high frequency of gram-positive pathogens seen during this study.


Asunto(s)
Agranulocitosis/complicaciones , Antibacterianos/uso terapéutico , Infecciones Bacterianas/tratamiento farmacológico , Neutropenia/complicaciones , Adolescente , Adulto , Anciano , Antibacterianos/administración & dosificación , Antibacterianos/efectos adversos , Infecciones Bacterianas/complicaciones , Infecciones Bacterianas/mortalidad , Canadá , Ensayos Clínicos como Asunto , Quimioterapia Combinada , Femenino , Granulocitos/efectos de los fármacos , Humanos , Leucemia/complicaciones , Recuento de Leucocitos , Masculino , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Moxalactam/administración & dosificación , Resistencia a las Penicilinas , Pronóstico , Distribución Aleatoria , Ticarcilina/administración & dosificación , Tobramicina/administración & dosificación
9.
J Bone Miner Res ; 15(12): 2431-42, 2000 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11127207

RESUMEN

Hypothyroidism in children causes developmental abnormalities in bone and growth arrest, while thyrotoxicosis accelerates growth rate and advances bone age. To determine the effects of thyroid hormones on endochondral bone formation, we examined epiphyseal growth plates in control, hypothyroid, thyrotoxic, and hypothyroid-thyroxine (hypo-T4)-treated rats. Hypothyroid growth plates were grossly disorganized, contained an abnormal matrix rich in heparan sulfate, and hypertrophic chondrocyte differentiation failed to progress. These effects correlated with the absence of collagen X expression and increased parathyroid hormone-related protein (PTHrP) messenger RNA (mRNA) expression. In thyrotoxic growth plates, histology essentially was normal but PTHrP receptor (PTHrP-R) mRNA was undetectable. PTHrP is a potent inhibitor of hypertrophic chondrocyte differentiation that acts in a negative feedback loop with the secreted factor Indian hedgehog (Ihh) to regulate endochondral bone formation. Thyroid hormone receptor alpha1(TRalpha1), TRalpha2, and TRbeta1 proteins were localized to reserve zone progenitor cells and proliferating chondrocytes in euthyroid rat cartilage; regions in which PTHrP and PTHrP-R expression were affected by thyroid status. Thus, dysregulated Ihh/PTHrP feedback loop activity may be a key mechanism that underlies growth disorders in childhood thyroid disease.


Asunto(s)
Cartílago/citología , Cartílago/metabolismo , Condrocitos/citología , Condrocitos/metabolismo , Proteínas/metabolismo , Receptores de Hormona Paratiroidea/metabolismo , Receptores de Hormona Tiroidea/metabolismo , Hormonas Tiroideas/fisiología , Animales , Desarrollo Óseo , Diferenciación Celular , Regulación del Desarrollo de la Expresión Génica , Placa de Crecimiento/citología , Placa de Crecimiento/metabolismo , Inmunohistoquímica , Hibridación in Situ , Proteína Relacionada con la Hormona Paratiroidea , Proteínas/genética , ARN Mensajero/metabolismo , Ratas , Ratas Sprague-Dawley , Receptor de Hormona Paratiroídea Tipo 1 , Receptores de Hormona Paratiroidea/genética , Hormonas Tiroideas/metabolismo
10.
J Bone Miner Res ; 9(12): 1865-73, 1994 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-7872051

RESUMEN

This paper aims to examine the relative contributions made by alcohol and iron overload and hypovitaminosis C to the osteoporosis associated with African hemosiderosis. To characterize this bone disorder, we examined double-tetracycline-labeled iliac crest bone biopsies and serum biochemistry in 53 black male drinkers, 38 with (Fe+) and 15 without (Fe-) iron overload, and in controls. We reasoned that abnormalities found in both patient groups were likely to be caused by alcohol abuse and those found only in the Fe+ group to be caused by iron overload and hypovitaminosis C (iron/C-). The patient groups differed only with respect to greater erosion depth (p < 0.05) and abnormal markers of iron overload in the Fe+ group. Ascorbic acid levels were lower in the Fe+ group than in controls (p < 0.001). Bone volume and trabecular thickness were significantly lower in both patient groups compared with controls and therefore likely caused by alcohol. There were no positive correlations between formation and erosion variables in either patient group, which suggests uncoupling of formation from erosion, possibly as a result of alcohol abuse. Prolonged mineralization lag time associated with thin osteoid seams was found in 32% of patients, affecting both groups. This rules out osteomalacia and suggests osteoblast dysfunction, probably caused by alcohol. The number of iron granules in the marrow correlated with erosion depth (r = 0.373, p < 0.01), trabecular number (r = -0.295, p < 0.05), and trabecular separation (r = 0.347, p < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Alcoholismo/complicaciones , Ácido Ascórbico/sangre , Hemosiderosis/complicaciones , Hierro/sangre , Osteoporosis/etiología , Adulto , África , Anciano , Alcoholismo/sangre , Alcoholismo/fisiopatología , Densidad Ósea , Hemosiderosis/sangre , Hemosiderosis/fisiopatología , Humanos , Ilion/química , Ilion/fisiopatología , Masculino , Persona de Mediana Edad , Osteoporosis/sangre , Osteoporosis/fisiopatología , Mielofibrosis Primaria/etiología
11.
J Bone Miner Res ; 5(2): 141-52, 1990 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-2316402

RESUMEN

We attempted to establish whether systemic changes in trabecular bone explain the development of stress fractures in the lower limbs during fluoride therapy for osteoporosis. To this end we compared transiliac bone biopsies obtained before treatment with those taken around the time of stress fractures after 14.3 +/- 10.9 (SD) months of therapy in six patients (group A). Biopsies from a comparable group of six patients without stress fractures at the time of the second biopsy (after 11.9 +/- 2.7 months of treatment) served for comparison (group B). The biopsies were processed undecalcified and examined by routine histomorphometry. The second biopsies did not show any significant improvement in mean bone volume or trabecular architecture. Although the second biopsies in group A had increased erosion surfaces (p less than 0.05) and greater osteoid volume (p less than 0.05), group B biopsies showed no difference in erosion surfaces but an increase in all osteoid parameters: osteoid volume (p less than 0.05), osteoid surface (p less than 0.05), and osteoid seam thickness (p less than 0.01). We reached the following conclusions: (1) the combination of increased erosion and replacement of removed bone by as yet unmineralized osteoid in the stress fracture group must have weakened bone and allowed the development of stress fractures. (2) Stress fracture patients may have mounted a less vigorous osteoblast response to fluoride than non-stress fracture patients. Under these conditions microfractures are likely to heal poorly and propagate to develop into full stress fractures. (3) Renal failure is a contraindication to fluoride therapy.


Asunto(s)
Fracturas por Estrés/patología , Fracturas de Cadera/patología , Ilion/efectos de los fármacos , Osteoporosis/tratamiento farmacológico , Fluoruro de Sodio/efectos adversos , Biopsia , Creatinina/sangre , Femenino , Fracturas por Estrés/inducido químicamente , Fracturas por Estrés/etiología , Fracturas de Cadera/inducido químicamente , Fracturas de Cadera/etiología , Humanos , Ilion/patología , Osteoporosis/complicaciones , Hormona Paratiroidea/sangre , Fluoruro de Sodio/metabolismo , Fluoruro de Sodio/uso terapéutico , Factores de Tiempo
12.
J Bone Miner Res ; 5 Suppl 1: S195-200, 1990 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-2339629

RESUMEN

We attempted to identify risk factors for the development of lower limb stress fractures during fluoride therapy for osteoporosis (OP). We compared 18 patients who developed 41 such fractures (26 periarticular, 6 femoral neck, 5 long bone shaft, 1 greater trochanter and 3 pubic rami fractures) during fluoride therapy, with 24 similarly treated patients who did not develop stress fractures. Treatment consisted of sodium fluoride 0.99 mg/kg per day, elemental calcium 1 g/day, and vitamin D. We obtained a previous fracture history, annual radiographs of the spine (fractures), hands (metacarpal cortical index, MCI) and pelvis (Singh index, femoral cortical index), three-monthly serum fluoride and alkaline phosphatase levels, and pretreatment transiliac bone biopsies (routine histomorphometry). The stress fracture group was found to have, before treatment: lower MCI (p less than 0.05), lower trabecular bone volume (p less than 0.05), a lower number of trabeculae (p less than 0.05), greater trabecular separation (p less than 0.05), less extensive eroded surfaces (p less than 0.05), a lower double/single tetracycline label ratio (p less than 0.05); and during treatment: more new spinal fractures (p less than 0.05) and higher serum alkaline phosphatase levels (p less than 0.01). We conclude that stress fracture patients had more severe trabecular and cortical OP and possibly a poorer bone-forming capacity before therapy than patients without stress fractures. We suspect that fluoride therapy may temporarily further weaken bone and so lead to stress fractures in severely osteoporotic patients.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Fracturas por Estrés/inducido químicamente , Osteoporosis/tratamiento farmacológico , Fluoruro de Sodio/efectos adversos , Anciano , Fosfatasa Alcalina/sangre , Biopsia , Creatinina/sangre , Femenino , Fracturas por Estrés/diagnóstico , Fracturas por Estrés/metabolismo , Humanos , Traumatismos de la Pierna/etiología , Masculino , Persona de Mediana Edad , Osteoporosis/complicaciones , Osteoporosis/diagnóstico por imagen , Radiografía , Factores de Riesgo , Fluoruro de Sodio/metabolismo , Fluoruro de Sodio/uso terapéutico
13.
Endocrinology ; 141(10): 3887-97, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11014246

RESUMEN

T3 is an important regulator of endochondral bone formation in epiphyseal growth plates. Growth arrest in juvenile hypothyroidism results from disorganization of growth plate chondrocytes and their failure to undergo hypertrophic differentiation, but it is unclear how T3 acts directly on chondrocytes or whether its actions involve other pathways. To address this issue, we investigated whether thyroid hormone receptors (TR) were localized to discrete regions of the unfused epiphysis by immunohistochemistry performed in tibial growth plates from 21-day-old rats and examined the effects of T3 on growth plate chondrocytes in agarose suspension cultures in vitro. TRalpha1, -alpha2, and -beta1 were expressed in reserve and proliferating zone chondrocytes, but not in hypertrophic cells, suggesting that progenitor cells and immature chondrocytes are the major T3 target cells in the growth plate. Chondrocytes in suspension culture expressed TRalpha1, -alpha2, and -beta1 messenger RNAs and matured by an ordered process of clonal expansion, colony formation, and terminal hypertrophic differentiation. Clonal expansion and proliferation of chondrocytes were inhibited by T3, which also induced alkaline phosphatase activity, expression of collagen X messenger RNA, and secretion of an alcian blue-positive matrix as early as 7 days after hormone stimulation. Thus, T3 inhibited chondrocyte clonal expansion and cell proliferation while simultaneously promoting hypertrophic chondrocyte differentiation. These data indicate that thyroid hormones concurrently and reciprocally regulate chondrocyte cell growth and differentiation in the endochondral growth plate.


Asunto(s)
Condrocitos/efectos de los fármacos , Condrocitos/patología , Placa de Crecimiento/efectos de los fármacos , Triyodotironina/farmacología , Animales , Animales Recién Nacidos/fisiología , Diferenciación Celular/efectos de los fármacos , División Celular/efectos de los fármacos , Línea Celular , Células Cultivadas , Senescencia Celular/efectos de los fármacos , Condrocitos/metabolismo , Condrocitos/fisiología , Placa de Crecimiento/metabolismo , Placa de Crecimiento/patología , Hipertrofia/patología , Masculino , Ratas , Ratas Sprague-Dawley , Receptores de Hormona Tiroidea/metabolismo , Tibia/efectos de los fármacos , Tibia/metabolismo , Tibia/patología
14.
Bone ; 31(4): 457-64, 2002 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-12398940

RESUMEN

The effects of glucocorticoid (GC) excess, thyrotoxicosis, and hypothyroidism on linear growth indicate that growth plate chondrocytes are exquisitely sensitive to GC and thyroid hormone (T(3)). Murine ATDC5 cells undergo chondrogenesis in vitro and were used to evaluate the effects of dexamethasone (Dex) and T(3) on cell proliferation and differentiation. Immature and differentiated ATDC5 cells expressed glucocorticoid and T(3)-receptor mRNAs. Cells proliferated and organized into cartilage-like nodules after 7 days. Chondrocyte maturation progressed over 9-40 days, with increasing alkaline phosphatase (ALP) activity, secretion of an Alcian blue-positive matrix, and mineralization of cartilage-like nodules. Dex reduced cell number over the 40 day period, causing inhibition of ALP activity and matrix production with failure of mineralization. Following withdrawal of Dex, chondrocytes proliferated and re-entered the differentiation and mineralization program, indicating that GC inhibition of chondrogenesis is reversible. In contrast, T(3) reduced cell proliferation, but induced ALP activity and increased matrix secretion earlier than in control cultures. Thus, GCs and T(3) regulate growth plate chondrocyte differentiation by distinct mechanisms. GCs arrest cell proliferation, differentiation, and cartilage mineralization and maintain chondrocyte precursors in a state of quiescence with the capacity to re-enter chondrogenesis. T(3) inhibits cell proliferation but accelerates differentiation to stimulate chondrogenesis.


Asunto(s)
Diferenciación Celular/efectos de los fármacos , Condrocitos/efectos de los fármacos , Dexametasona/farmacología , Triyodotironina/farmacología , Animales , División Celular/efectos de los fármacos , Línea Celular , Condrocitos/citología , Inmunohistoquímica , Ratones , ARN Mensajero/genética , Receptores de Glucocorticoides/genética , Receptores de Hormona Tiroidea/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
15.
Bone ; 30(1): 259-66, 2002 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11792595

RESUMEN

Thyroid hormone (T(3)) plays a key role in endochondral ossification. The process relies on the coordinated synthesis and degradation of cartilage matrix and is disrupted in juvenile hypothyroidism, leading to abnormal skeletal development. Mast cells synthesize and store matrix-degrading enzymes. We examined whether thyroid status influences skeletal mast cell distribution in growing rats to determine whether they might modulate the actions of T(3) in bone. Tibiae were collected for histological, histochemical, immunohistochemical, and immunofluorescence analysis. Mast cells were increased throughout the bone marrow in hypothyroid rats compared with euthyroid, thyrotoxic, and hypothyroid-thyroxine replaced animals. Large numbers were present in metaphyseal marrow adjacent to the growth plate in hypothyroid animals and cells were distributed evenly throughout the marrow. Very few mast cells were present in metaphyseal marrow in other groups, but their numbers increased with increasing distance from the growth plate. T(3) receptor alpha1 (TRalpha1) was expressed in the nucleus and cytoplasm of skeletal mast cells, whereas TRalpha2 and TRbeta1 were restricted to the cytoplasm. Localization of TRs was not affected by altered thyroid status. Thus, disrupted endochondral ossification in hypothyroidism may be mediated in part by skeletal mast cells, which express TR proteins and may function as T(3) target cells.


Asunto(s)
Células de la Médula Ósea/metabolismo , Mastocitos/metabolismo , Receptores de Hormona Tiroidea/metabolismo , Receptores alfa de Hormona Tiroidea , Receptores beta de Hormona Tiroidea , Animales , Células de la Médula Ósea/citología , Recuento de Células , Hipotiroidismo/tratamiento farmacológico , Hipotiroidismo/metabolismo , Hipotiroidismo/patología , Inmunohistoquímica , Masculino , Mastocitos/citología , Ratas , Ratas Sprague-Dawley , Tirotoxicosis/metabolismo , Tirotoxicosis/patología , Tiroxina/uso terapéutico
16.
Int J Radiat Oncol Biol Phys ; 38(1): 183-90, 1997 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-9212022

RESUMEN

PURPOSE: A clonogenic assay was used to determine the effects of the growth factors TGFbeta1 and TGFbeta3 on the radiation responses of a normal rat epithelial cell line (IEC6) and a human colonic carcinoma epithelial cell line (Widr). METHODS AND MATERIALS: The radiation sensitivity and ability to recover from potentially lethal damage (PLD), of preconfluent monolayer cultures, was assessed in the presence of the growth factors for 24 h prior to, during, and after irradiation. RESULTS: The surviving fractions of both cell lines assessed immediately following irradiation were unaffected by TGFbeta1 or TGFbeta3. However, TGFbeta3 (but not TGFbeta1) significantly reduced the amount of PLD recovery in the Widr cells (but not in the IEC6 cells). This was associated with a reduction in the shoulder region of the survival curve, rather than a change in slope. A comparative analysis of the effects of TGFbetas 1 and 3 on cell cycle events in the two cell lines demonstrated significantly more Widr cells in the S phase, in the presence of TGFbeta3 only, compared to the controls. This remained constant both before and immediately following irradiation. In the IEC6 cell line TGFbeta3 produced an increase in the numbers of G1 phase cells, characteristic of a G1 arrest. CONCLUSION: It seems likely that TGFbeta3-induced radiosensitisation in Widr cells, 6 h after a single dose of irradiation, is related to its effects on cell cycle events such that the failure of these cells to arrest in G1, either before or after irradiation, results in significantly reduced recovery from DNA damage. This, however, may not be the only mechanism by which this growth factor produces this effect. Indeed, it will also be necessary to investigate these effects in in vivo models and to determine the response to fractionated irradiation before the potential therapeutic benefit of both the differential effects observed between the two TGFbeta isoforms and also between the malignant and normal cell lines can be fully assessed.


Asunto(s)
Ciclo Celular/efectos de los fármacos , Factor de Crecimiento Transformador beta/farmacología , Animales , Ciclo Celular/efectos de la radiación , División Celular/efectos de los fármacos , División Celular/efectos de la radiación , Línea Celular/efectos de los fármacos , Línea Celular/efectos de la radiación , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/efectos de la radiación , Humanos , Tolerancia a Radiación , Ratas , Células Tumorales Cultivadas/efectos de los fármacos , Células Tumorales Cultivadas/efectos de la radiación , Ensayo de Tumor de Célula Madre
17.
J Endocrinol ; 157(2): 225-35, 1998 May.
Artículo en Inglés | MEDLINE | ID: mdl-9659285

RESUMEN

Short stature is one of the most well recorded long term sequelae for adult survivors of childhood malignancies. It has become increasingly apparent that cytotoxic chemotherapy, as well as craniospinal irradiation, has a major impact on growth, but there are virtually no studies which explore the mechanisms by which these cytotoxic drugs affect growth. We have used an in vitro system to investigate the direct effects of a range of chemotherapeutic agents on the proliferative responses of rat tibial growth plate chondrocytes, both in suspension and monolayer culture. The glucocorticoids and purine anti-metabolites reduced chondrocyte proliferation both in monolayer and suspension cultures and this resulted from an increase in cell doubling times with a concomittant reduction in the numbers of S phase cells. DNA damaging agents (e.g. actinomycin-D) were also able to reduce chondrocyte proliferation, both in monolayer and suspension culture. This, however, was the result of a cell cycle arrest and subsequent cell death. In our studies, methotrexate had no significant effect on the proliferative responses of the chondrocytes either in monolayer or suspension culture. These results indicate direct effects of a range of chemotherapeutic agents on the proliferative responses of growth plate chondrocytes. Both cytostatic and cytotoxic effects were observed although the impact of either the potential loss of cells from the proliferative pool during chondrocyte differentiation, or the reduction in the rate of chondrocyte turnover on long bone growth remains to be elucidated.


Asunto(s)
Antineoplásicos/farmacología , Condrocitos/efectos de los fármacos , Placa de Crecimiento/efectos de los fármacos , Animales , Antibióticos Antineoplásicos/farmacología , Antimetabolitos Antineoplásicos/farmacología , Carboplatino/farmacología , Ciclo Celular/efectos de los fármacos , División Celular/efectos de los fármacos , Células Cultivadas , Condrocitos/citología , Cisplatino/farmacología , Dactinomicina/farmacología , Dexametasona/farmacología , Etopósido/farmacología , Placa de Crecimiento/citología , Masculino , Mercaptopurina/farmacología , Metotrexato/farmacología , Prednisolona/farmacología , Ratas , Ratas Sprague-Dawley , Tioguanina/farmacología
18.
Infect Control Hosp Epidemiol ; 17(6): 360-4, 1996 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8805066

RESUMEN

OBJECTIVE: To determine the incidence of aspergillosis in patients with leukemia or bone marrow transplants during a construction-associated outbreak, and the effect of an environmental control program for Aspergillus. DESIGN: Clinical, microbiological, and pathological records were reviewed retrospectively once the outbreak was appreciated, and prospectively thereafter, to determine the presence or absence of aspergillosis and duration of neutropenia. SETTING: A university tertiary-care center with a single designated hematology-oncology unit. PATIENTS: From January 1988 to September 1993, there were 141 patients with leukemia or bone marrow transplants identified as being neutropenic during 231 admissions to this specialized unit. INTERVENTIONS: Installation of wall-mounted portable high-efficiency particulate air (HEPA)-filter air purifiers, application of copper-8-quinolinolate-formulated paint, replacement of perforated ceiling tiles with nonperforated type, sealing of all windows, replacement of horizontal, dust-accumulating blinds with vinyl, opaque, roller shades, and systematic and regular cleaning of surfaces. RESULTS: Thirty-six cases of nosocomial aspergillosis were diagnosed during this period. The incidence density (ID) in the preconstruction period was 3.18 per 1,000 days at risk. During construction activity-before the implementation of a control strategy-the ID increased dramatically to 9.88 per 1,000 days at risk. With infection control measures implemented and continued construction work, the ID decreased to 2.91 per 1,000 days at risk, comparable to the preconstruction baseline rate. CONCLUSIONS: An environmental control strategy incorporating widely available technology may have played an important role in controlling this outbreak of construction-associated invasive aspergillosis.


Asunto(s)
Contaminación del Aire Interior/efectos adversos , Aspergilosis/prevención & control , Infección Hospitalaria/prevención & control , Brotes de Enfermedades , Ventilación/normas , Contaminación del Aire Interior/análisis , Aspergilosis/complicaciones , Aspergilosis/epidemiología , Trasplante de Médula Ósea , Infección Hospitalaria/complicaciones , Infección Hospitalaria/epidemiología , Arquitectura y Construcción de Hospitales , Humanos , Huésped Inmunocomprometido , Incidencia , Control de Infecciones/métodos , Leucemia , Neutropenia/etiología , Servicio de Oncología en Hospital , Estudios Prospectivos , Estudios Retrospectivos
19.
Infect Control Hosp Epidemiol ; 19(10): 791-4, 1998 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9801292

RESUMEN

An outbreak of Serratia marcescens infections occurred in a university tertiary-care hospital. Alcohol-free chlorhexidine solutions were contaminated with S marcescens. The majority of patient and chlorhexidine strains had similar pulsed field-gel electrophoresis banding patterns. Chlorhexidine was recalled, and the rate of S marcescens isolation returned to baseline. Chlorhexidine without alcohol should not be used as an antiseptic.


Asunto(s)
Antiinfecciosos Locales , Clorhexidina , Infección Hospitalaria/etiología , Infecciones por Serratia/etiología , Serratia marcescens/aislamiento & purificación , Infección Hospitalaria/microbiología , Electroforesis en Gel de Campo Pulsado , Femenino , Hospitales Universitarios , Humanos , Masculino , Persona de Mediana Edad , Quebec , Infecciones por Serratia/microbiología
20.
Am J Trop Med Hyg ; 35(3): 491-5, 1986 May.
Artículo en Inglés | MEDLINE | ID: mdl-3706620

RESUMEN

Two cases of cutaneous leishmaniasis of 12 and 27 months duration are described. These were acquired in Saudi Arabia and Ethiopia. The cases were treated with 8 and 4 weeks of ketoconazole, respectively, with an excellent response.


Asunto(s)
Cetoconazol/uso terapéutico , Leishmaniasis/tratamiento farmacológico , Administración Oral , Adulto , Femenino , Humanos , Cetoconazol/administración & dosificación , Persona de Mediana Edad , Factores de Tiempo
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