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1.
Clin Plast Surg ; 46(1): 105-114, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30447822

RESUMO

After massive weight loss, deflation of the tissues and loss of skin elasticity in the face and neck can result in the appearance of accelerated facial aging. Surgical facial rejuvenation can be successfully performed with several modifications. Proper preoperative counseling and expectation management regarding staged or ancillary procedures is recommended. Wide undermining of the face and neck, and extended postauricular incisions are required to allow for mobilization of excess skin and access to the mobile superficial musculoaponeurotic system (SMAS). Fat transfer into the deep malar compartment for midface volumizing is helpful. Treatment of the SMAS and platysma are universally necessary.


Assuntos
Contorno Corporal/métodos , Pescoço/cirurgia , Ritidoplastia/métodos , Redução de Peso , Humanos
2.
Aesthet Surg J ; 37(7): 837-846, 2017 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-28333253

RESUMO

Background: This is the third survey exploring the quality of cosmetic training in plastic surgery residency. We focused on determining: (1) the applied modalities and extent of resident exposure; and (2) resident confidence in performing variable cosmetic procedures. Objectives: To analyze trends in resident exposure and confidence in aesthetic plastic surgery procedures from the standpoint of program directors (PDs) and residents. Methods: The survey was developed and e-mailed to 424 residents enrolled in the ASAPS Residents Program and 95 PDs. Both independent and integrated programs were included. The questions were posed in a five-point ranking format. Univariate statistical analysis was used to examine all aspects. The results were analyzed in relation to our previous surveys in 2008 and 2011. Results: Thirty-three PDs (34.7%) and 224 (52.8%) residents responded. Residents felt most confident with abdominoplasty, breast reduction, and augmentation-mammaplasty. Facial aesthetic procedures, especially rhinoplasty and facelift, were perceived as "challenging." The three most preferred modalities of aesthetic education were, in descending order, residents' clinic, staff cosmetic patients, and cadaver dissections. Both residents and PDs felt a need for more training especially in facial procedures. Only 31.5% of residents who planned to focus on cosmetic surgery felt ideally prepared integrating cosmetic surgery into their practice (compared to 50% in previous surveys). Conclusions: Despite improvements observed from 2008 to 2011 published surveys, there are still challenges to be met especially in facial cosmetic procedures. It is suggested that resident clinics and cadaver courses be universally adopted by all training programs.


Assuntos
Internato e Residência , Percepção , Diretores Médicos/psicologia , Procedimentos de Cirurgia Plástica/educação , Cirurgia Plástica/educação , Competência Clínica/estatística & dados numéricos , Feminino , Humanos , Masculino , Procedimentos de Cirurgia Plástica/tendências , Cirurgia Plástica/tendências , Inquéritos e Questionários
3.
Plast Reconstr Surg ; 139(1): 139e-150e, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28027251

RESUMO

LEARNING OBJECTIVES: After studying this article, the participant should be able to: 1. Define the anatomy of the lower eyelid tarsoligamentous framework and the related periorbital retaining ligaments, and cite their surgical relevance. 2. Perform a systematic functional and aesthetic evaluation of the lower eyelid focusing on the lid-cheek junction, and clinical tests that predict the need for lateral canthal tightening. 3. Enumerate the different approaches to lower eyelid rejuvenation and discuss their merits/limitations. 4. Describe surgical strategies to blend the lid-cheek junction and tighten the lateral canthal retinaculum. SUMMARY: Modern lower lid blepharoplasty requires a thorough understanding of periorbital anatomy, age-related changes of the lid-cheek junction, and the variables controlling lower lid tone and position. The surgical strategies are best used in a graded fashion. The patient with isolated lower lid bags may be treated by transconjunctival fat resection alone. Additional mild skin laxity can be improved with skin pinch or skin-only undermining. Skin resurfacing using chemical peeling or laser can further address fine lines. In these patients with an abnormality of the lid-cheek junction, release of the medial orbicularis oculi muscle and variable amounts of the orbicularis retaining ligament is essential. This is combined with orbital fat resection or repositioning through a transconjunctival or transcutaneous skin-muscle flap. The transcutaneous approach most often necessitates lateral canthal tightening to optimize lid margin control. Generally, the degree of laxity dictates whether a canthopexy or a canthoplasty is most appropriate. Lateral canthal procedures can be applied to patients displaying clinical signs predictive of lid malposition and to those presenting with varying degrees of established lid descent.


Assuntos
Blefaroplastia/métodos , Idoso , Medicina Baseada em Evidências , Pálpebras/anormalidades , Pálpebras/anatomia & histologia , Feminino , Humanos , Ligamentos/anatomia & histologia , Pessoa de Meia-Idade
4.
Aesthet Surg J ; 36(7): 743-55, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26994394

RESUMO

BACKGROUND: Competition among our sister cosmetic specialties continues to increase. Once a field dominated by plastic surgeons, there is a clear trend toward increased competition from core and non-core disciplines. While these marketplace trends are obvious, how such competition has affected academia or peer reviewed publications is less clear. OBJECTIVES: We analyzed the most cited peer reviewed facial aesthetic literature over the past five decades to see if marketplace trends are echoed in a similar manner across the academic disciplines of plastic surgery, otolaryngology, dermatology, and ophthalmology. METHODS: The top 50 cited articles for each decade from the 1970s to the 2010s were identified for the topics of facelift, rhinoplasty, browlift, and blepharoplasty using the Thomson/Reuters Web of Knowledge. Data collected were: the number of citations/article, first authors' specialty affiliation, and journal specialty affiliation. Data were plotted graphically and trends were analyzed. RESULTS: With regards to first authorship, plastic surgery had the highest percentage across all surgeries at every time point, except for rhinoplasty from 2010-present, when otolaryngology had a higher percentage (48% vs 40%). Observed trends demonstrated: (1) increasing contributions from otolaryngology in rhinoplasty, facelift, and browlift; and (2) increasing contributions from ophthalmology in blepharoplasty. Plastic surgery journals are the most common platform for publication across all four surgeries. CONCLUSIONS: Plastic surgeons, and plastic surgery journals, still remain a strong force in academic facial cosmetic surgery. However, it appears that the competition from non-plastic surgeons observed in clinical practice is being mirrored in the area of journal publications. We as a specialty need to continue to strive for high quality academic productivity.


Assuntos
Autoria , Bibliometria , Publicações Periódicas como Assunto/estatística & dados numéricos , Procedimentos de Cirurgia Plástica/estatística & dados numéricos , Cirurgia Plástica/estatística & dados numéricos , Face , Humanos
5.
Aesthet Surg J ; 36(2): 237-43, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26384712

RESUMO

BACKGROUND: Over the past decade there has been a dramatic rise in the use of technology. Evaluating our use of technology is crucial to advancing the next generation of plastic surgeons. OBJECTIVES: The goals of this study were to assess the current use of technology by residents, help Program Directors allocate financial resources, and predict the future of technology and education. METHODS: A 17-question online survey was emailed to American Society for Aesthetic Plastic Surgery resident/fellow members (n = 447). The survey evaluated current use of technology, preferred use of educational resources, and directions for the future. Ample space was allocated for free response questions. RESULTS: The response rate was 40%. The average age of respondents was 32 years old (standard deviation 3.7). The majority (86.5%) of residents own iPhones, and 90% of residents own tablets. There was a heavy daily reliance on smartphone technology. Sixty percent of residents used physical textbooks on a weekly basis. The Plastic Surgery Education Network was used on a weekly basis by 42% of residents. In contrast, 78% of residents were not aware of, or had never used, the readily available digital aesthetic resource (RADAR) Resource iPad application. CONCLUSIONS: In order to remain at the forefront of education, we as a specialty need to adapt with technology. Program Directors should support integrating technology with electronic access to educational materials. There exists an opportunity in resident education to increase awareness and utilization of the RADAR Resource. The future of plastic surgery education will be reliant on platforms like the iPhone and iPad to conveniently provide large volumes of information with only a finger touch.


Assuntos
Instrução por Computador , Técnicas Cosméticas , Educação de Pós-Graduação em Medicina/métodos , Internato e Residência , Procedimentos de Cirurgia Plástica/educação , Cirurgia Plástica/educação , Ensino/métodos , Livros de Texto como Assunto , Adulto , Atitude do Pessoal de Saúde , Atitude Frente aos Computadores , Instrução por Computador/tendências , Técnicas Cosméticas/tendências , Currículo , Difusão de Inovações , Educação de Pós-Graduação em Medicina/tendências , Feminino , Humanos , Internato e Residência/tendências , Masculino , Pessoa de Meia-Idade , Procedimentos de Cirurgia Plástica/tendências , Cirurgia Plástica/tendências , Inquéritos e Questionários , Ensino/tendências
6.
Aesthetic Plast Surg ; 39(6): 847-55, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26311559

RESUMO

BACKGROUND: While the literature is replete with articles about body contouring after bariatric surgery, little information exists regarding the outcomes of facelift following massive weight loss (MWL). A case report and a technique article are the only sources available addressing this issue. This pilot study objectively examines the effects of MWL in the cervicofacial region and results after facelift. METHODS: A retrospective review of seven patients who underwent facelift after MWL (>100 pounds) was performed. Patient's change in appearance was objectively evaluated using an apparent age model. Forty blinded reviewers assessed pre- and postoperative photographs of seven MWL and eleven non-MWL female patients. The reviewers estimated the apparent age for each subject. Reduction in apparent age was calculated by comparing patient's apparent age against actual age. RESULTS: The preoperative apparent age of MWL patients was 5.1 years older than their actual age (p < 0.02) compared to the increased preoperative apparent age of 1.2 years in non-MWL subjects (p > 0.05); suggesting MWL patients appear older than their actual age. Post-operatively, the apparent age reduction in MWL patients was 6.0 years; and their apparent age after surgery was 0.9 year less than their actual age (p > 0.05). In contrast, the control group exhibited an apparent age reduction of 5.4 years and a postoperative apparent age 4.2 years younger than their actual age (p < 0.01). Apparent age reduction was not significantly different for the two groups (p > 0.05). Age, BMI, and follow-up were similar between groups (p > 0.05). CONCLUSIONS: MWL may accelerate apparent cervicofacial aging. Facelift following MWL enhances cervicofacial appearance and significantly reduces apparent age. We hope this study stimulates further interest in the study of facial esthetics in this increasing population. LEVEL OF EVIDENCE III: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.


Assuntos
Rejuvenescimento , Ritidoplastia , Redução de Peso , Feminino , Humanos , Pessoa de Meia-Idade , Projetos Piloto , Estudos Retrospectivos
8.
J Burn Care Res ; 35(5): e338-42, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24577227

RESUMO

The vacuum-assisted closure device (VAC) is associated with improved wound healing outcomes. Its use as a bolster device to secure a split-thickness skin graft has been previously demonstrated; however, there is little published evidence demonstrating its benefits specifically in the burn population. With use of the VAC becoming more commonplace, its effect on skin graft take and overall time to healing in burn patients deserves further investigation. Retrospective review of burn registry database at a high-volume level I trauma center and regional burn center during a 16-month period was performed. Patients who had a third-degree burn injury requiring a split-thickness skin graft and who received a VAC bolster were included. Data points included age, sex, burn mechanism, burn location, grafted area in square centimeters, need for repeat grafting, percent graft take, and time to complete reepithelialization. Sixty-seven patients were included in the study with a total of 88 skin graft sites secured with a VAC. Age ranged from <1 year to 84 years (average 41 years). The average grafted area was 367 ± 545 cm. The three most common were the leg, thigh, and arm (28, 15, and 12%, respectively). Average percent graft take was 99.5 ± 1.5%. Notably, no patients returned to the operating room for repeat grafting. The average time to complete reepithelialization was 16 ± 7 days. The VAC is a highly reliable and reproducible method to bolster a split-thickness skin graft in the burn population. The observed rate of zero returns to the operating room for repeat grafting was especially encouraging. Its ability to conform to contours of the body and cover large surface areas makes it especially useful in securing a graft. This method of bolstering results in decreased repeat grafting and minimal graft loss, thus decreasing morbidity compared with conventional bolster dressings.


Assuntos
Queimaduras/cirurgia , Tratamento de Ferimentos com Pressão Negativa/instrumentação , Transplante de Pele , Cicatrização/fisiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Unidades de Queimados , Criança , Pré-Escolar , Feminino , Sobrevivência de Enxerto , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Sistema de Registros , Estudos Retrospectivos , Centros de Traumatologia , Resultado do Tratamento
9.
Ann Plast Surg ; 66(6): 643-7, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21042177

RESUMO

The knowledge of patient preference is crucial for plastic surgeons to determine optimal marketing strategies. Conjoint analysis is a statistical technique whereby research participants make a series of trade-offs. Analysis of these trade-offs reveals the relative importance of component attributes. This study will evaluate the relative importance of attributes that influence the selection and decision-making process when choosing a plastic surgeon. A questionnaire consisting of 18 plastic surgeon profiles was rated by 111 patients. Attributes analyzed were as follows: travel distance, number of years in practice, board certification status, method of referral, office décor, and procedure cost. A traditional full-profile conjoint analysis was performed. Subjects consisted of 10 men and 101 women (n = 111). Median age was 51 years (range, 19-72). The "mean importance" of the attributes are as follows: board certification status, 39.7%; method of referral, 23.5%; distance from home to office, 13.2%; office décor, 9.0%; number of years in practice, 7.5%; and cost of procedure, 7.2%. Internal validity checks showed a high correlation (Pearson ρ = 0.995; P < 0.001). This pilot study demonstrates that conjoint analysis is a very powerful tool for market research in the health care system. The level of importance for each attribute reliably helps plastic surgeons to understand the preferences of their patients, thus being able to improve marketing strategies for private practices and institutions. The present study indicates that the most important attributes were board certification and method of referral.


Assuntos
Comportamento de Escolha , Preferência do Paciente , Cirurgia Plástica , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários , Adulto Jovem
10.
J Plast Reconstr Aesthet Surg ; 63(11): 1825-31, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19962360

RESUMO

BACKGROUND: This is the first study defining the facial anthropometric and aesthetic measurements in Indian American women (IAW). METHODS: This is a prospective cohort study involving evaluation of facial photographs. Frontal, lateral and basal photographs were taken of IAW (n=102), and 30 anthropometric measurements were determined. Proportions were compared with published North American white women (NAWW) norms. Judges (n=6) evaluated the photographs for aesthetics using a visual analogue scale. Attractive IAW (top 15%) were compared with average IAW (remaining 85%) and average NAWW. All completed a facial self-esteem survey. RESULTS: There were significant differences between IAW and NAWW in 25 of 30 facial measurements. Six measurements correlated with aesthetic scores: intercanthal distance, mouth width, nasolabial angle, midface height 2, ear length and nasal height. Attractive IAW had nine measurements approximating NAWW features, 15 measurements similar to average IAW values and two measurements distinct from both average IAW and average NAWW. Attractive IAW had higher facial self-esteem scores than average IAW. CONCLUSIONS: Facial measurements in IAW are much different from NAWW, and these results will assist in preoperative planning. Several features are correlated with attractiveness in IAW: larger and wider-set eyes, a smaller midface, a smaller nose with greater tip rotation, smaller ears and a larger mouth. Attractive IAW display many measurements typical of average IAW and several measurements that reflect average NAWW values. These results contribute to concepts of transcultural aesthetics--for a minority ethnic group, facial beauty appears to be an assimilation of deep-rooted ethnic features with prevailing cultural traits and aesthetic standards.


Assuntos
Antropometria/métodos , Estética , Indígenas Norte-Americanos , Ritidoplastia/métodos , Autoimagem , Adolescente , Adulto , Feminino , Seguimentos , Humanos , Satisfação do Paciente , Estudos Prospectivos , Estados Unidos , Adulto Jovem
11.
Int Wound J ; 5(4): 490-501, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19031493

RESUMO

The authors sought to evaluate the ability of locally administered enhanced cryoprecipitate (eCryo) to improve the wound healing of split thickness skin grafts (STSG) and their donor sites. An STSG (5 x 5 cm) was harvested on the back of 30 rats and divided into four areas that were then treated in one of the following groups: A: 'standard' dressing without STSG; B: eCryo without STSG; C: eCryo with STSG coverage and D: STSG alone. Macroscopic and histological assessments (histomorphometric grading scale and cellular composition) were evaluated at days 7, 14, 21 and 28 for wound healing. All wound beds as well as STSGs healed well without any complications. Eighty per cent of the STSG showed a histological graft take of >75% after 28 days. There were no statistically significant differences of macroscopic or histological results between the groups at any time point. Preparation of eCryo is easy and effective. Its use as an adhesive for STSGs is safe and shows similar results as controls. The theoretical benefits of eCryo did not show significant differences. Possible reasons as well as important findings for future research on wound healing are discussed.


Assuntos
Fator VIII/uso terapêutico , Fibrinogênio/uso terapêutico , Transplante de Pele , Cicatrização/efeitos dos fármacos , Administração Cutânea , Análise de Variância , Animais , Bandagens , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Fator VIII/farmacocinética , Fibrinogênio/farmacocinética , Masculino , Necrose/patologia , Ratos , Ratos Sprague-Dawley , Segurança , Higiene da Pele/métodos
13.
Invest Ophthalmol Vis Sci ; 47(2): 738-44, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16431975

RESUMO

PURPOSE: Vascular endothelial growth factor (VEGF), insulin-like growth factor (IGF)-I, and growth hormone (GH) are major regulators of physical growth, as well as normal and pathologic retinal development. Ocular tissues are protected by the blood-ocular barrier. This study was conducted to test the hypothesis that the ontogenic profiles of VEGF, IGF-I, and GH in the rat serum, vitreous fluid, and retina are compartment specific, and that the vitreous is a reservoir for retinal growth factors. METHODS: Sprague-Dawley rat pups were killed at birth (postnatal day [P]0) and at P7, P14, and P21. At death, serum, vitreous fluid, and retinal homogenates were analyzed for ontogeny of VEGF, IGF-I, and GH. RESULTS: VEGF levels were 10 times higher in the vitreous than in serum at all stages of development. Vitreous and serum VEGF levels progressively declined, with lowest concentrations at P21. Retinal VEGF levels increased with the highest concentration at P21. IGF-I levels in the vitreous decreased from P7 through P21. IGF-I levels in serum and retinal homogenates increased with advancing postnatal age. Although IGF-I levels were four times higher in the vitreous than in the retina at P0, equilibration was achieved at P21. GH levels in the vitreous were 10 times lower than serum levels, were decreased at P14 and P21, and remained unchanged from P0 through P21 in the retina. CONCLUSIONS: VEGF and IGF-I act in concert to promote retinal development with the vitreous fluid as a reservoir. The ontogenic profiles of VEGF, IGF-I and GH in the serum and ocular compartments are specific. These differences should be considered when therapies for ROP are proposed.


Assuntos
Animais Recém-Nascidos/sangue , Animais Recém-Nascidos/crescimento & desenvolvimento , Hormônio do Crescimento/sangue , Fator de Crescimento Insulin-Like I/metabolismo , Retina/crescimento & desenvolvimento , Fator A de Crescimento do Endotélio Vascular/sangue , Corpo Vítreo/crescimento & desenvolvimento , Animais , Feminino , Fenômenos Fisiológicos Oculares , Gravidez , Ratos , Ratos Sprague-Dawley , Retina/metabolismo , Corpo Vítreo/metabolismo
14.
J Investig Med ; 53(5): 253-62, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16042959

RESUMO

BACKGROUND: Preterm infants exposed to O2 with mechanical ventilation often develop bronchopulmonary dysplasia (BPD), a form of chronic lung disease (CLD). The pathogenesis of BPD/CLD involves dysmorphic microvasculature and disrupted alveolarization. This may be due to impaired vascular endothelial growth factor (VEGF) and VEGF receptor expression. METHODS: To examine the ontogeny of VEGF and VEGF receptors in baboon lungs from 125 to 185 (term) days gestation and to determine whether exposure to O2 and mechanical ventilation alter these ontogenic profiles, we examined lung specimens from three O2-exposed groups: (1) animals delivered at 125 days gestation and exposed to O2 for 14 days as needed; (2) animals delivered at 140 days gestation and exposed to O2 for 10 days as needed; and (3) animals delivered at 140 days gestation and exposed to 100% O2 for 10 days. Lungs from gestational age-matched controls were also examined at 125, 140, 160, 175, and 185 (term) days. RESULTS: VEGF189 was the most abundant splice variant in the lungs at all stages of development. Extremely premature baboons developing BPD/CLD had higher lung VEGF121 messenger ribonucleic acid (mRNA) expression. However, transcripts for VEGF189, VEGF165, and VEGF receptors (Fms-like tyrosine kinase-1 [Flt-1], kinase-insert domain receptor [KDR]/fetal liver kinase-1 [Flk-1], and neuropilin 1) were suppressed in the BPD models. CONCLUSIONS: We conclude that impaired VEGF and VEGF receptor mRNA expression in lungs from extremely premature baboons developing BPD/CLD may contribute to dysmorphic microvasculature and disrupted alveolarization.


Assuntos
Pulmão/metabolismo , Doenças dos Macacos , Papio , Nascimento Prematuro/metabolismo , Síndrome do Desconforto Respiratório/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Animais , Animais Recém-Nascidos , Modelos Animais de Doenças , Feminino , Técnica Indireta de Fluorescência para Anticorpo , Regulação da Expressão Gênica no Desenvolvimento , Idade Gestacional , Técnicas Imunoenzimáticas , Pulmão/embriologia , Oxigênio/administração & dosagem , Oxigenoterapia , Gravidez , RNA Mensageiro/metabolismo , Respiração Artificial , Síndrome do Desconforto Respiratório/patologia , Síndrome do Desconforto Respiratório/terapia , Fator A de Crescimento do Endotélio Vascular/genética , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/genética , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/metabolismo
15.
Am J Obstet Gynecol ; 192(3): 924-31, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15746693

RESUMO

OBJECTIVE: The purpose of this study was to examine whether the pregnant rabbit model can be used as a viable model for the study of non-infection-mediated preterm birth. STUDY DESIGN: Timed pregnant New Zealand rabbits were injected with a single dose of RU486 on day 22 of gestation. Three doses (50 mg, 75 mg, and 100 mg) were administered intramuscularly, intraperitoneally, or subcutaneously. The rabbits were monitored for preterm delivery. Progesterone, cortisol, and cytokine levels were examined before the induction and after delivery. Uterine and cervical progesterone, cortisol, and cytokine levels were determined after delivery. RESULTS: RU486 resulted in 100% preterm delivery in all doses and modes of administration, compared with 0% of controls. Intramuscular administration appeared to generate the most favorable preterm delivery time. Rabbits that received 100 mg RU486 intramuscularly showed significantly decreased serum progesterone levels and uterine progesterone levels, compared with 100 mg subcutaneously and intraperitoneally. CONCLUSION: RU486 that was administered intramuscularly appears to be a potent and effective method for inducing preterm birth. This model of hormonally mediated preterm birth might serve as a useful model for the investigation of the possible mechanisms of preterm labor.


Assuntos
Abortivos Esteroides/administração & dosagem , Mifepristona/administração & dosagem , Nascimento Prematuro/induzido quimicamente , Animais , Citocinas/análise , Modelos Animais de Doenças , Feminino , Hidrocortisona/análise , Injeções Intramusculares , Injeções Intraperitoneais , Injeções Subcutâneas , Gravidez , Progesterona/análise , Coelhos
16.
Pediatr Pulmonol ; 39(1): 5-14, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15521085

RESUMO

Matrix metalloproteinases (MMPs) regulate the formation of normal lung architecture. Extremely premature infants exposed to hyperoxia and mechanical ventilation often develop lung inflammation and injury. We hypothesized that an imbalance between MMPs and their tissue inhibitors plays a key role. Our hypothesis was tested to: 1) examine the ontogeny of lung MMPs and tissue inhibitors of metalloproteinases (TIMPs); and 2) determine the effects of hyperoxia and mechanical ventilation on lung MMPs and TIMPs in premature newborn baboons developing chronic lung disease/bronchopulmonary dysplasia (CLD/BPD). Lung specimens were obtained from five groups of gestational controls (GCs) sacrificed at 125, 140, 160, 175, and 185 (term) days of gestation, one fetal baboon model of CLD/BPD delivered at 125 days, and two at 140 days of gestation. Paraffin-embedded lung tissue sections were examined for pathological changes, and frozen lung specimens were analyzed for MMPs-1, -2, -8, and -9; TIMPs-1 and -2; and messenger RNA expression of type I collagen. In GCs, MMP-1 and -9 were elevated in the last trimester, whereas MMP-2 and -8 levels were decreased. Significant changes in lung architecture were noted in the BPD models. MMP-1 was increased in the 125-day model, but decreased in both 140-day models. MMP-8 and collagen mRNA levels were decreased, while MMP-9 and MMP-9 to TIMP-1 ratios were increased in all BPD models. We conclude that an imbalance between MMP-9 and TIMP-1 leading to excessive MMP-9 activity contributes to lung inflammation and edema in CLD/BPD.


Assuntos
Displasia Broncopulmonar/enzimologia , Displasia Broncopulmonar/fisiopatologia , Pulmão/enzimologia , Metaloproteinase 9 da Matriz/análise , Metaloproteinase 9 da Matriz/biossíntese , Inibidor Tecidual de Metaloproteinase-1/análise , Inibidor Tecidual de Metaloproteinase-1/biossíntese , Animais , Animais Recém-Nascidos , Displasia Broncopulmonar/veterinária , Doença Crônica , Modelos Animais de Doenças , Edema/fisiopatologia , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Inflamação/fisiopatologia , Pulmão/patologia , Pneumopatias/enzimologia , Pneumopatias/fisiopatologia , Pneumopatias/veterinária , Metaloproteinase 9 da Matriz/farmacologia , Papio , RNA Mensageiro/análise , Inibidor Tecidual de Metaloproteinase-1/farmacologia
17.
Pediatr Pulmonol ; 35(6): 456-62, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12746943

RESUMO

In order to test the hypothesis that early postnatal exposure to dexamethasone (Dex) influences matrix metalloproteinases (MMP)-2 and -9, as well as their tissue inhibitors (TIMP-1 and -2) in the developing rat lung, newborn rats (3 litters/group) were treated with low Dex (0.1 mg/kg/day, IM), high Dex (0.5 mg/kg/day), or equivalent volumes of saline at 5 days postnatal age (P5), P6, and P7. Lung weight and lung MMP and TIMP levels were determined at sacrifice (7 days postinjection, P14; at weaning, P21; and at adolescence, P45, n = 10/group and time). Dex did not adversely affect lung weight or lung MMP-2 levels, which peaked in all groups at P21 and then fell by P45. In contrast, Dex decreased TIMP-2 at all time intervals, but achieved statistical significance only at P45. An imbalance in MMP-2/TIMP-2 ratio was noted at P21, with elevations occurring in the low and high Dex-treated groups. Lung MMP-9 levels remained comparable with controls during low Dex treatment. However, high Dex exposure resulted in elevated lung MMP-9 levels at P21 and P45. Lung TIMP-1 levels increased only with high Dex exposure at P14 and P21, whereas the lung MMP-9/TIMP-1 ratio was elevated at P21 in the high Dex group, and at P45 in both Dex-treated groups. These data provide evidence that early postnatal dexamethasone results in an imbalance between gelatinase-A and -B, and their tissue inhibitors in the developing rat lung. These changes may be responsible, in part, for some of the known maturational effects of steroids on lung structure in the newborn.


Assuntos
Dexametasona/farmacologia , Pulmão/enzimologia , Metaloproteinase 2 da Matriz/metabolismo , Inibidor Tecidual de Metaloproteinase-2/metabolismo , Inibidores Teciduais de Metaloproteinases/metabolismo , Animais , Animais Recém-Nascidos , Dexametasona/administração & dosagem , Imuno-Histoquímica , Pulmão/química , Pulmão/crescimento & desenvolvimento , Pulmão/metabolismo , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley
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