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1.
Indian J Dermatol ; 56(4): 415-7, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21965851

RESUMEN

Psoriatic onycho-pachydermo-periostitis (POPP) is a rare subset of psoriatic arthritis. It is usually localized to the hands and it is characterized by onychodistrophy, soft tissue thickening above the distal phalanx and periosteal reaction. The resolution is very slow due to the involvement of nails and bone. Low dose methotrexate and anti-tumor necrosis factor-α (anti-TNF-α) agents are the suggested therapies. We report a case of a 53-year-old man affected by palmo-plantar slight psoriatic dermatitis, who presented a rapid onset of POPP. Rx imaging showed enthesitis and a moderate phalanx erosion with articular spaces narrowing and swollen periosteal reaction. A magnetic resonance imaging test of the hands showed an initial stage of synovitis and extensive periostitis of the distal phalangeal tufts. The patient has been treated with oral methotrexate for a month with a rapid clinical improvement and pain reduction. As POPP at first manifests as a painful onycodistrophy, it can easily be confused with bacterial perionyxis. The delay in making the correct diagnosis, and therefore, the delay in giving a proper treatment would mean the progressive articular erosion and the permanent invalidation of the patient's ability to use his hands.

2.
Photodermatol Photoimmunol Photomed ; 23(6): 229-33, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17986058

RESUMEN

BACKGROUND: In recent years, narrow-band ultraviolet B (NB-UVB, 311-313 nm) has been found to be beneficial for early-stages mycosis fungoides (MF). The aim of this study is to investigate the effect of NB-UVB in 20 patients with early-stage MF. METHODS: Twenty patients (10 women and 10 men, mean age 54 +/- 22 years) with clinically and histologically confirmed MF were enrolled in the study. All of the patients had clinical stage I disease (T1 or T2, N0, M0) with cutaneous involvement, consisting of patch-stage disease of limited extent, in 50% of the cases (stage IA), and more widespread in the other 50% (stage IB). All the patients were treated with NB-UVB therapy until more than 95% clearance of the patient's skin lesions had occurred. RESULTS: A complete response was achieved in 90% of the cases after a mean of 29 +/- 14 treatments within a mean period of 4 months (range 1-8 months), with an average cumulative dose of 25 +/- 16.77 J/cm(2). In the follow-up period, relapse occurred after a mean period of 8 months (range 3-17 months), and then therapy was restarted. CONCLUSION: This study provides evidence that NB-UVB might be an efficient option for stage IA and IB MF patients.


Asunto(s)
Micosis Fungoide/patología , Micosis Fungoide/radioterapia , Terapia Ultravioleta/métodos , Anciano , Biopsia , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores de Tiempo
3.
J Eur Acad Dermatol Venereol ; 21(10): 1369-74, 2007 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17958843

RESUMEN

BACKGROUND: The treatment of vitiligo is still a challenge, but ultraviolet B narrow-band (UVB-NB) therapy has been recently reported to be an effective and safe therapeutic option in patients with vitiligo. OBJECTIVE: The purpose of this study is a critical evaluation of the variants (body sites, age, duration of the disease, and duration of the therapy) influencing the clinical response to UVB-NB therapy. METHODS: Sixty patients (23 male and 37 female), aged 6 to 70 years, with vitiligo, were treated with UVB-NB therapy over a maximum period of 2 years. The evaluation of the percentage of repigmentation was done through photographs. RESULTS: The lesions located on the face obtained a complete repigmentation in 68% of the patients, on the neck in 57.89%, and on the trunk in 50% within the first year of the therapy. In young patients vs. adults patients, the lesions located on the neck obtained a complete repigmentation in 83.33% vs. 46.15%, on the upper limbs in 28.57% vs. 9.52%, and on the lower limbs in 25% vs. 16.67%. In patients with vitiligo of recent onset, the lesions located on the neck obtained a complete repigmentation in 83.33%, on the upper limbs in 33.33%, and on the lower limbs in 28.57%. Hands did not give a positive response in either groups. CONCLUSION: This study shows that certain body sites respond better than others to the UVB-NB therapy; patients, aged less than 20 years, with recent vitiligo, achieve more repigmentation; the duration of the therapy can influence the response of the lesions over hands and lower limbs, showing only mild repigmentation.


Asunto(s)
Terapia Ultravioleta , Vitíligo/radioterapia , Adolescente , Adulto , Factores de Edad , Anciano , Distribución de Chi-Cuadrado , Niño , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pigmentación de la Piel/efectos de la radiación , Factores de Tiempo , Resultado del Tratamiento
4.
Minerva Stomatol ; 49(4): 149-54, 2000 Apr.
Artículo en Italiano | MEDLINE | ID: mdl-11040540

RESUMEN

BACKGROUND: The aim of this research is to outline a procedure able to promote specific cellular differentiation and proliferation with consequent periodontal regeneration. To achieve this goal, use was made of various compounds supposed to have the capacity of aiding periodontal regeneration. METHODS: The cells utilised for this study were obtained from explants of human periodontal ligaments. Their proliferation and differentiation capacity was examined in the presence of: coral granules (350, 500 mu), collagene type 1, growth factors (Platelet derived growth factor, PDGF and Transforming growth factor beta 1, TGF beta 1), both on their own and in different combination with one another. The differentiation activity was evaluated by ultrastructural morphological method (Transmission electron microscope-TEM) and by spectrophotometric investigation of the alkaline phosphatasis (ALP). RESULTS: The data show that the coral granules and among the growth factors used only TGF beta 1 stimulate the differentiation activity of the periodontal ligament cells valued on the basis of their capacity of producing ALP. These data are supported by the observation with TEM. CONCLUSIONS: From these results it is suggested that there may be therapeutic efficiency in the periodontal field of substances promoting cellular proliferation and differentiation.


Asunto(s)
Ligamento Periodontal/citología , Técnicas de Cultivo de Célula/métodos , Células Cultivadas , Humanos
5.
Anat Embryol (Berl) ; 197(5): 349-57, 1998 May.
Artículo en Inglés | MEDLINE | ID: mdl-9623668

RESUMEN

Structure and relationships of stromal cells were studied by light (LM) and transmission electron microscopy (TEM) in the perimedullary spaces that form the growing cortex of the chick embryo tibia. Observation under LM showed that in all perimedullary spaces the interstices between the cells carpeting the bone surface and the endothelial lining contain stromal cells surrounded by an amorphous matrix. Two types of stromal cells were distinguished: stellate and spindle-shaped. All stromal cells are alkaline phosphatase-positive. TEM showed that both types of stromal cells have cytoplasmic processes of various length and calibre, coming into contact with each other as well as with endothelial cells and osteoblasts or bone lining cells. Capillaries were found to have a continuous endothelial lining; occasionally endothelial cells radiate cytoplasmic processes towards stromal cells. Along all the above-mentioned cellular contacts adherens and/or gap junctions were often observed. The results of the present study, together with our previous findings on osteoblast-osteocyte relationships, show that the cells of the osteogenic lineage form a continuous protoplasmic network that extends from the osteocytes to the vascular endothelium, passing through osteoblasts (or bone lining cells) and stromal cells. The occurrence of gap junctions among this cytoplasmic network, namely of junctions enabling metabolic and electric coupling, indicates that it forms a functional syncytium, suggesting the hypothesis that the activity of the cells pertaining to the osteogenic lineage might be regulated not only by diffusion (volume transmission) through the intercellular fluids of systemic (hormones) and local factors (cytokines, etc.) but also by signals issued through the cytoplasmic network of the osteogenic cells (wiring transmission).


Asunto(s)
Osteón/citología , Células del Estroma/ultraestructura , Tibia/citología , Fosfatasa Alcalina/metabolismo , Animales , Matriz Ósea/ultraestructura , Embrión de Pollo , Diáfisis/citología , Uniones Comunicantes/ultraestructura , Histocitoquímica , Microscopía Electrónica , Osteocitos/ultraestructura , Células del Estroma/enzimología
6.
Clin Rheumatol ; 15(6): 563-72, 1996 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-8973865

RESUMEN

The effect of mechanical stresses on osteogenesis, the viability of osteocytes and their metabolic activity in organ culture of bones intermittently loaded "in vitro" are reported. Metatarsal bones, isolated from 12-day-old rats, were cultured in BGJb medium (with 10% foetal calf serum, 75 micrograms/ml of ascorbic acid, 100 U/ml of penicillin and 100 micrograms/ml of streptomycin), in humidified air enriched by 5% CO2 and 30% O2, and loaded in our original device for 1/2 an hour at 1 Hz. homotypic isolated and unloaded bones, cultured in the same medium, were taken as controls. The ALP (alkaline phophatase activity) increases in the media of loaded bones in comparison with the control bones. The percentage of viable osteocytes is significantly greater in loaded than in control bones. TEM observations demonstrate that in both loaded and control unloaded bones, osteocytes show well developed organelle machinery and several gap junctions with adjacent cellular processes. In the cells of loaded bones, however, a higher number of cytoplasmic organelles and gap junctions were found. In particular, RER increases twice, gap junctions three times. The induced osteogenesis and the TEM observations demonstrate the suitability of this experimental model and support the recent advanced hypothesis according to which the mechanical loading may exert a trophic function on osteocytes, stimulating both the proteic synthesis in the above-mentioned cells and the cell-to-cell communication. Furthermore, the loading is likely to exert a biological stimulus on osteoblasts via signalling molecules produced by osteocytes.


Asunto(s)
Huesos Metatarsianos/fisiología , Osteocitos/citología , Osteogénesis/fisiología , Soporte de Peso/fisiología , Fosfatasa Alcalina/metabolismo , Animales , Supervivencia Celular , Retículo Endoplásmico Rugoso/ultraestructura , Uniones Comunicantes/ultraestructura , Huesos Metatarsianos/enzimología , Huesos Metatarsianos/ultraestructura , Microscopía Electrónica , Técnicas de Cultivo de Órganos , Osteocitos/ultraestructura , Ratas , Ratas Wistar , Estrés Mecánico
7.
Anat Embryol (Berl) ; 191(4): 351-7, 1995 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-7645761

RESUMEN

An ultrastructural-morphometric study was carried out on the process of osteoid maturation in growing surfaces of parallel-fibered chick bone. The aim was to investigate the distribution, size and amount of collagen fibrils (CFs), as well as the proteoglycan (PG) content, throughout the osteoid seam and in the adjacent bone. The results show that the organic components secreted by osteoblasts undergo complete maturation inside the osteoid seam only. Proceeding from the secreting plasma membrane of osteoblasts (osteoidogenic surface) towards the mineralizing surface, we found that CFs gradually increase in diameter but not in number per surface unit. As a consequence, the proportion of osteoid seam occupied by CF increases too, at the expense of the interfibrillar substance. PG content also decreases inversely in this direction. In the adjacent bone, CF size and density do not change significantly with respect to the mature osteoid close to the mineralizing surface.


Asunto(s)
Desarrollo Óseo , Matriz Ósea/ultraestructura , Colágeno/análisis , Proteoglicanos/análisis , Animales , Matriz Ósea/química , Pollos , Colágeno/ultraestructura , Microscopía Electrónica
8.
Bone ; 13(5): 363-8, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1419377

RESUMEN

Scanning electron microscopy (SEM) was used to quantify the intercellular relationships between osteoblasts and osteocytes on the growing endosteal surfaces of the medullary canal of the tibia in four rabbits of different ages. The area of each osteoblast was measured on the SEM micrographs by means of an Image Analyzer. The number of osteocyte cytoplasmic processes was indirectly evaluated by counting the canalicular openings present on the same microscopic fields after the removal of the osteoblasts. The metabolic activity of the osteoblasts was indirectly evaluated from their shape, and the structure was analyzed by transmission electron microscope (TEM) in sections taken from the samples studied by SEM. In all four animals, the surface area of the osteoblasts (OA) was found to vary a great deal, whereas the density of canalicular openings was fairly uniform. Moreover, although the OA mean value increases significantly with the age of the animals, the density of canalicular openings does not; it would therefore appear that the older the animal and the more flattened the osteoblasts, the greater the number of canaliculi beneath them. Since osteoblast activity has previously been shown to be inversely proportional to the area of the protoplasm in contact with the bone surface, it appears that the less active osteoblasts should contact a greater number of osteocyte cytoplasmic processes. These findings suggest that osteocytes might play an important role in modulating osteoblast activity and in recruiting osteoblasts that differentiate into osteocytes, possibly by means of inhibitory signals transmitted via gap junctions.


Asunto(s)
Osteoblastos/ultraestructura , Osteocitos/ultraestructura , Tibia/citología , Tibia/crecimiento & desarrollo , Animales , Desarrollo Óseo , Comunicación Celular , Microscopía Electrónica , Microscopía Electrónica de Rastreo , Conejos
9.
Acta Anat (Basel) ; 137(4): 350-8, 1990.
Artículo en Inglés | MEDLINE | ID: mdl-2368590

RESUMEN

The morphological changes undergone by the osteoblast at the ultrastructural level, during its differentiation into osteocyte, were studied in the primary parallel-fibred bone of the newborn rabbit by means of incomplete three-dimensional reconstruction from partially serial-sectioned preosteocytes. The findings obtained suggest that the formation of osteocyte cytoplasmic processes is an asynchronous and asymmetrical phenomenon that seems to precede the mineralization of the organic matrix and to give rise to an asymmetrical mature osteocyte. The functions of cytoplasmic processes as regards bone formation, cell nutrition and osteoblast modulation are discussed. The mechanism by which the osteoblast 'enters' the bone matrix is hypothesized.


Asunto(s)
Animales Recién Nacidos/anatomía & histología , Osteocitos/citología , Tibia/embriología , Animales , Animales Recién Nacidos/fisiología , Diferenciación Celular/fisiología , Citoplasma/ultraestructura , Procesamiento de Imagen Asistido por Computador , Microscopía Electrónica , Osteoblastos/citología , Osteoblastos/patología , Osteoblastos/ultraestructura , Osteocitos/fisiología , Osteocitos/ultraestructura , Conejos , Tibia/citología , Tibia/ultraestructura
10.
Bone ; 11(6): 401-6, 1990.
Artículo en Inglés | MEDLINE | ID: mdl-2078434

RESUMEN

Ultrastructural studies were carried out on intercellular relationships during osteocyte differentiation in primary parallel-fibred bone of newborn rabbit. It was found that throughout the whole differentiative process preosteocytes are in close relationship with the neighboring cells (osteoblasts, osteocytes) by means of variously-shaped intercellular contacts (invaginated finger-like, side-to-side, and end-to-end) and two types of specialized junctions: gap and adherens. The pivotal role played by these contacts and junctions in osteocyte differentiation and activity is considered in the context of their particular functional significance.


Asunto(s)
Uniones Intercelulares/ultraestructura , Osteocitos/ultraestructura , Animales , Comunicación Celular/fisiología , Diferenciación Celular/fisiología , Uniones Intercelulares/fisiología , Microscopía Electrónica , Osteoblastos/citología , Osteoblastos/fisiología , Osteoblastos/ultraestructura , Osteocitos/citología , Osteocitos/fisiología , Conejos
12.
Ital J Orthop Traumatol ; 8(1): 117-25, 1982 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-7174280

RESUMEN

As part of a programme of research designed to assess the respective roles of osteoclasts and osteocytes in the processes of bone resorption, the metabolic activity of these cells was evaluated indirectly by a morphometric method in the compact bone of human tibias from subjects of various ages, both normal and those affected by osteoporosis. Statistical analysis of the quantitative data was in agreement with the microradiographic examination of the sections, and showed that whereas the intensity of osteoclastic resorption varied in the various subjects according to age, periosteocytic osteolysis--in the classical sense of a phenomenon involving widening of the lacunae detectable with the optical microscope--did not occur in compact bone whether it was normal or highly porotic.


Asunto(s)
Osteoclastos/metabolismo , Osteocitos/metabolismo , Osteoporosis/metabolismo , Adulto , Anciano , Femenino , Humanos , Masculino , Microrradiografía , Persona de Mediana Edad , Osteólisis/metabolismo , Tibia/metabolismo , Tibia/patología
14.
Anat Embryol (Berl) ; 162(4): 393-401, 1981.
Artículo en Inglés | MEDLINE | ID: mdl-7347493

RESUMEN

Structure and size of the osteoblasts have been analyzed during growth of the tibial diaphyses in chick embryos from 10 days incubation until hatching. Statistical analyses of the results indicate that both size and density of the osteoblasts gradually decrease from the subperiosteal towards the endosteal regions of the shaft; the osteoblast secretory territory, on the other hand increases. These structural changes of the osteoblasts, which appear to be related to differences of the appositional growth rate, seem to derive mainly from structural modifications of differentiated osteoblasts rather than from differentiation of new osteoblasts, of progressively smaller size, from osteoprogenitor cells. The data reported in this paper compared with those in previous investigations indicate that the size of the osteoblasts does not significantly differ in animals of different species.


Asunto(s)
Embrión de Pollo , Osteoblastos/citología , Tibia/embriología , Animales , Biometría , Factores de Tiempo
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