PubMed Health⌕ Search

Biomedical subjects

Lydia M Ferreira

Publications and source records attributed to Lydia M Ferreira.

12 recordsLinked to original sources
PubMed2006

Upregulation of TGF-beta1 expression may be necessary but is not sufficient for excessive scarring.

Transforming growth factor beta 1 (TGF-beta1) upregulation has been implicated in hypertrophic scars and keloids, but it is unclear if it is the cause or an effect of excessive scar formation. In this study, we overexpressed TGF-beta1 in fibroblasts and characterized its role. Normal human dermal fibroblasts were genetically modified to overexpress TGF-beta1 as the wild-type latent molecule or as a mutant constitutively active molecule. TGF-beta1 secretion was measured, as were the effects of TGF-beta1 upregulation on cell proliferation, expression of smooth muscle cell alpha actin (SMC alpha-actin) and ability to contract collagen lattices. Fibroblasts were implanted intradermally into athymic mice and tissue formation was analyzed over time by histology and immunostaining. Gene-modified fibroblasts secreted approximately 20 times the TGF-beta1 released by control cells, but only cells expressing mutant TGF-beta1 secreted it in the active form. Fibroblasts expressing the active TGF-beta1 gene had increased levels of SMC alpha-actin and enhanced ability to contract a collagen lattice. After intradermal injection into athymic mice, only fibroblasts expressing active TGF-beta1 formed "keloid-like" nodules containing collagen, which persisted longer than implants of the other cell types. We conclude that upregulation of TGF-beta1 by fibroblasts may be necessary, but is not sufficient for excessive scarring. Needed are other signals to activate TGF-beta1 and prolong cell persistence.

Actins↗
PubMed2005

[Epidemiological profile of mandible fractures treated at the Federal University of São Paulo-Paulista Medical School].

BACKGROUND: Mandible fractures can result in esthetic, functional and financial problems and their epidemiological patterns have changed in many locations. This study was carried out to detect these changes, aiming to compare data of patients with mandible fractures treated at the Sao Paulo Hospital (UNIFESP-EPM) from June 1999 to March 2002 with data of patients treated from January 1991 to March 1996. METHODS: Information on most affected gender and age, most often fractured mandible segment, associated injuries, treatment and complications of 98 victims of mandible fracture admitted from June 1999 to March 2002 were compared to the same data of 166 patients treated from January 1991 to March 1996. RESULTS: the most affected gender and age ranges remain the same. Aggressions surpassed traffic accidents as the main etiology. Incidence of associated injuries and multiple fractures in the mandible decreased, a fact probably related to the change in etiology. The most affected segment is still the body of the mandible. The most used type of treatment in both samples was internal rigid fixation with miniplates and the number of complications decreased, due to the higher standard of patient care. CONCLUSION: Mandible fractures in the São Paulo population have undergone epidemiological changes and this knowledge enables local authorities to establish adequate measures for prevention and treatment.

Accidents, Traffic↗
PubMed2005

Helium-neon laser in viability of random skin flap in rats.

BACKGROUND AND OBJECTIVES: The purpose of this study was to determine the role of helium-neon (He-Ne) laser random skin flap viability in rats. STUDY DESIGN/MATERIALS AND METHODS: Experimentally controlled randomized study. Forty-eight Wistar-EPM rats were used, weighed, and divided into 4 groups with 12 rats each. The random skin flap was performed measuring 10 x 4 cm, with a plastic sheet interposed between the flap and the donor site. The Group 1 (control) underwent sham irradiation with He-Ne laser. The Group 2 was submitted to laser irradiation, using the punctual contact technique on the skin flap surface. The Group 3 was submitted to laser irradiation surrounding the skin flap, and the Group 4 was submitted to laser irradiation both on the skin flap surface and around it. The experimental groups were submitted to He-Ne laser irradiation with 3 J/cm(2) energy density immediately after the surgery and for the four subsequent days. The percentage of necrotic area of the four groups was calculated at the 7th post-operative day, through a paper-template method. RESULTS: Group 1 reached an average necrotic area of 48.86%; Group 2, 38.67%; Group 3, 35.34%; and Group 4, 22.61%. After the statistic analysis, results showed that all experimental groups reached statistically significant values when compared to the control group, and Group 4 was the best one, when compared to all groups of this study (P<0.001). CONCLUSION: The He-Ne laser irradiation was efficient to increase random skin flap viability in rats.

Animals↗
PubMed2002

V-Y advancement flap for the reconstruction of partial and full thickness defects of the upper lip.

We analysed the records of 25 patients who had their upper lips reconstructed after resection of a tumour. All the repairs were done with triangular cutaneous and musculocutaneous flaps with a skin island with V-Y advancement, and a subcutaneous or muscular pedicle with or without mucosa. The choice of flap was based on the width of the defect after the tumour had been resected. A subcutaneous pedicled flap was used in 14 patients; a musculocutaneous flap not including the mucosa in 5, and including the mucosa in 6. This flap can be used to repair upper lip defects of any thickness. The procedure is quite safe from a circulatory point of view and the flap has the advantage of requiring only one procedure. It is aesthetically satisfactory in most patients and maintains the good function and sensitivity of the lip.

Esthetics↗
PubMedDate not supplied

A stratigraphic approach to the superficial musculoaponeurotic system and its anatomic correlation with the superficial fascia.

The superficial musculoaponeurotic system (SMAS) is not included in the International Anatomic Terminology, although it is a fundamental anatomical structure in plastic surgeons. In the literature, the concept of the SMAS is not clear, leading to repercussions in the treatment of the SMAS via the various techniques for rhytidoplasty. This review article, in its aim to conceptualize the SMAS, has as a referential parameter the basic stratigraphic pattern of the human body construction. A systematic review of the literature was performed through Medline, ISI-Web of Science, and Lilacs databases as well as through classical treatises of anatomy for analyses of the stratigraphic principle of SMAS and its relationship to the fascia. In fact, SMAS, an anatomic entity, is part of this construction model. The stratigraphic approach followed in this article to describe the SMAS is novel in the literature and allows for a unified anatomic understanding of SMAS for the scientific community.

Adipose Tissue↗
PubMedDate not supplied

[Sentinel lymph node in children with melanoma--case report].

OBJECTIVE: To present a case of a child who was subjected to sentinel lymph node biopsy for cutaneous melanoma. DESCRIPTION: A 12 year-old child with Dysplastic Nevus Syndrome developed melanoma on the lumbar region. The excision biopsy revealed a melanoma with depth of 1.5 mm. The patient was submitted to amplification of the margins 2 cm in all directions and the sentinel node was also excised. The histopathological exam did not show residual disease. Sentinel on exam did not show metastases either under hematoxylin-eosin stain or immunohistochemistry (S-100 and HMB45). Therefore, RT-PCR for tyrosinase mRNA was positive. The patient has been followed for twelve months without evidence of recurrence. COMMENTS: Childhood melanoma is rare, corresponding to less than 1% of malignant tumors in children. Data point to a worldwide increase in its incidence. Melanoma occurs in melanocytic lesions in 70% and in the remaining 30% it occurs de novo. Melanoma is very aggressive, so the survival depends on an early diagnosis. Sentinel lymph node biopsy has selected patients to complete lymphadenectomy. Some authors have been using this technique in childhood melanoma.

English Abstract↗