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1.
J Aging Soc Policy ; 30(1): 1-23, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-28768107

RESUMO

Food insecurity has been associated with poor health and health outcomes among older adults, yet food assistance resources are available and underutilized. Routine screening and referral for food insecurity in primary care is one avenue to connect food-insecure older adults with available resources. This qualitative study aims to better understand the beliefs of primary care providers (PCPs) about food security screening and referrals in a primary care setting and perceived barriers to implementation. PCPs (n = 16) who have older adult patients but do not routinely screen for food insecurity were interviewed by phone. PCPs recognize the importance of food security for older patients and discuss nutrition and food access with patients under certain circumstances. Concerns emerged with regard to implementing a systematic screening and referral process: limited time to meet with patients, a lack of resources for addressing food insecurity, and prioritizing food insecurity at both the health system and the patient levels. Despite perceived challenges, PCPs are receptive to the idea of systematically screening and referring patients to external resources for food assistance and support. Barriers could be addressed by health systems prioritizing food insecurity as a health concern and public and private payers providing reimbursement for screening.


Assuntos
Abastecimento de Alimentos , Pessoal de Saúde/psicologia , Pessoal de Saúde/estatística & dados numéricos , Atenção Primária à Saúde , Idoso , Estudos Transversais , Feminino , Recursos em Saúde , Humanos , Masculino , Programas de Rastreamento/métodos , Pessoa de Meia-Idade , Pesquisa Qualitativa
2.
J Clin Invest ; 108(6): 831-41, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11560952

RESUMO

The proapoptotic proteinase inhibitor TIMP-3 is the only molecule of this family thought to influence cell death. We examined epithelial apoptosis in TIMP-3-deficient mice during mammary gland involution. Lactation was not affected by the absence of TIMP-3, but glandular function, as measured by gland-to-body weight ratio and production of beta-casein, was suppressed earlier during post-lactational involution than in controls. Histological examination revealed accelerated lumen collapse, alveolar-epithelial loss, and adipose reconstitution in Timp-3(-/-) females. Epithelial apoptosis peaked on the first day of involution in Timp-3-null glands but at day 3 in wild-type littermates. Unscheduled activation of gelatinase-A was evident by zymography and correlated with earlier fragmentation of fibronectin in Timp-3(-/-) mammary. To obtain independent evidence of the proapoptotic effects of TIMP-3 deficiency, we introduced recombinant TIMP-3-releasing pellets into regressing Timp-3(-/-) mammary tissue and showed that this treatment rescued lumen collapse and epithelial apoptosis. Ex vivo, involuting Timp-3(-/-) mammary tissue demonstrated accelerated epithelial apoptosis that could be reduced by metalloproteinase inhibition. The physiological relevance of TIMP-3 became apparent as Timp-3(-/-) dams failed to reestablish lactation after brief cessation of suckling. Thus, TIMP-3 is a critical epithelial survival factor during mammary gland involution.


Assuntos
Apoptose/fisiologia , Glândulas Mamárias Animais/citologia , Glândulas Mamárias Animais/metabolismo , Inibidor Tecidual de Metaloproteinase-3/deficiência , Inibidor Tecidual de Metaloproteinase-3/fisiologia , Tecido Adiposo/anatomia & histologia , Animais , Técnicas de Cultura , Ativação Enzimática , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Feminino , Fibronectinas/metabolismo , Lactação/fisiologia , Glândulas Mamárias Animais/fisiologia , Metaloproteinase 2 da Matriz/metabolismo , Camundongos , Camundongos Knockout , Gravidez , Inibidor Tecidual de Metaloproteinase-3/genética
3.
Biol Reprod ; 65(3): 680-8, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11514328

RESUMO

Adult mammary tissue has been considered "resting" with minimal morphological change. Here, we reveal the dynamic nature of the nulliparous murine mammary gland. We demonstrate specific changes at the morphological and cellular levels, and uncover their relationship with the murine estrous cycle and physiological levels of steroid hormones. Differences in the numbers of higher-order epithelial branches and alveolar development led to extensive mouse-to-mouse mammary variations. Morphology (assigned grades 0-3) ranged from a complete lack of alveoli to the presence of numerous alveoli emanating from branches. Morphological changes were driven by epithelial proliferation and apoptosis, which differed between ductal versus alveolar structures. Proliferation within alveolar epithelium increased as morphological grade increased. Extensive alveolar apoptosis was restricted to tissue exhibiting grade 3 morphology, and was approximately 14-fold higher than at all other grades. Epithelial proliferation and apoptosis exhibited a positive relationship with serum levels of progesterone, but not with 17beta-estradiol. Compared with other estrous stages, diestrus was unique in that the morphological grade, epithelial proliferation, apoptosis, and progesterone levels all peaked at this stage. The regulated tissue remodeling of the mammary gland was orchestrated with mRNA changes in specific matrix metalloproteinases (MMP-9 and MMP-13) and specific tissue inhibitors of metalloproteinases (TIMP-3 and TIMP-4). We propose that the cyclical turnover of epithelial cells within the adult mammary tissue is a sum of spatial and functional coordination of hormonal and matrix regulatory factors.


Assuntos
Estradiol/sangue , Ciclo Estral/fisiologia , Glândulas Mamárias Animais/citologia , Progesterona/sangue , Animais , Apoptose , Divisão Celular , Colagenases/genética , Diestro , Células Epiteliais/citologia , Feminino , Regulação da Expressão Gênica , Glândulas Mamárias Animais/crescimento & desenvolvimento , Metaloproteinase 13 da Matriz , Metaloproteinase 9 da Matriz/genética , Camundongos , Camundongos Endogâmicos C57BL , RNA Mensageiro/análise , Inibidor Tecidual de Metaloproteinase-3/genética , Inibidores Teciduais de Metaloproteinases/genética , Inibidor Tecidual 4 de Metaloproteinase
4.
Plast Reconstr Surg ; 107(7): 1637-46, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11391179

RESUMO

The role of total calvarial reconstruction in the treatment of sagittal synostosis remains controversial, especially in patients younger than 1 year of age. The purpose of this study was to prospectively evaluate the efficacy of a single surgical technique for total calvarial reconstruction (the reversal exchange technique) in patients younger than 1 year of age who had a radiographically confirmed diagnosis of sagittal synostosis. Twenty-three consecutive patients underwent the reversal exchange technique of total calvarial reconstruction at a median age of 3 months (age range, 6 weeks to 10 months). Quantitative assessments were performed on the basis of preoperative and postoperative (minimum, 6 months) measurements of the cephalic index (cranial width/cranial length x 100) taken from three-dimensional computed tomography scans, which were obtained in 18 of 23 patients. Aesthetic assessments were performed on the basis of the grading of preoperative and postoperative photographs, obtained in 17 of 23 patients, by three independent raters who were blinded as to the surgical technique. The mean preoperative cephalic index was 65.0, and the mean postoperative index was 76.4, yielding a mean improvement of 11.4 (17.5 percent). By photographic evaluation, 12 of 17 patients (70.6 percent) were classified as having a normal head shape (grade 4) and five of 17 (29.4 percent) as having minor residual deformities (grade 3). No patients were identified as having significant residual deformities (grades 1 or 2). There were two intraoperative complications and one postoperative complication, none of which resulted in permanent morbidity. It was concluded that the reversal exchange technique of total calvarial reconstruction provided significant improvement in head shape on the basis of quantitative measurements (cephalic index) and independent evaluations of aesthetic improvement.


Assuntos
Craniossinostoses/cirurgia , Procedimentos de Cirurgia Plástica , Crânio/cirurgia , Cefalometria , Humanos , Lactente , Masculino , Estudos Prospectivos
5.
Cell Death Differ ; 8(1): 16-29, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11313699

RESUMO

IGF-II is a growth factor implicated in human cancers and animal tumor models. While the mitogenic properties of IGF-II are well documented, its ability to suppress apoptosis in vivo has never been proven. We generated independent MMTV-IGF-II transgenic mice to examine the control of epithelial apoptosis at the morphological, cellular and molecular levels during the physiological event of postlactation mammary involution. Transgenic IGF-II expression was achieved in mammary epithelium and increased IGF-II bioactivity was confirmed by phosphorylation of the insulin receptor substrate-1, a signaling molecule downstream of the type I IGF receptor. IGF-II overexpression induced a delay in mammary involution, as evident by increased mammary gland to body weight ratios and persistence of both functionally intact lobulo-alveoli and mammary epithelial cellularity. The delayed mammary involution resulted from a significant reduction in mammary epithelial apoptosis, and not from increased epithelial proliferation. Recombinant IGF-II pellets implanted into involuting mammary glands of wild-type mice provided further evidence that IGF-II protein inhibited local epithelial apoptosis. At the molecular level, phosphorylated Akt/PKB, but not Erk1 or Erk2, persisted in IGF-II overexpressors and temporally correlated with reduced epithelial apoptosis. Levels of the phosphatase PTEN were unaltered in the transgenic tissue suggesting that the maintenance of Akt/PKB phosphorylation resulted from sustained phosphorylation rather than altered dephosphorylation of PIP-3. Together, this data reveal that IGF-II inhibits apoptosis in vivo and this effect correlates with prolonged phosphorylation of Akt/PKB


Assuntos
Apoptose , Células Epiteliais/metabolismo , Fator de Crescimento Insulin-Like II/metabolismo , Glândulas Mamárias Animais/fisiologia , Proteínas Serina-Treonina Quinases , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Supressoras de Tumor , Animais , Apoptose/efeitos dos fármacos , Implantes de Medicamento , Células Epiteliais/citologia , Células Epiteliais/efeitos dos fármacos , Proteínas Substratos do Receptor de Insulina , Fator de Crescimento Insulin-Like II/administração & dosagem , Fator de Crescimento Insulin-Like II/genética , Lactação/fisiologia , Glândulas Mamárias Animais/citologia , Glândulas Mamárias Animais/efeitos dos fármacos , Vírus do Tumor Mamário do Camundongo/genética , Camundongos , Camundongos Transgênicos , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno , Proteínas Quinases Ativadas por Mitógeno/metabolismo , PTEN Fosfo-Hidrolase , Fosfoproteínas/metabolismo , Monoéster Fosfórico Hidrolases/metabolismo , Fosforilação , Regiões Promotoras Genéticas , Proteínas Proto-Oncogênicas c-akt , Transgenes
6.
Cell ; 103(1): 41-50, 2000 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-11051546

RESUMO

Osteoprotegerin-ligand (OPGL) is a key osteoclast differentiation/activation factor essential for bone remodeling. We report that mice lacking OPGL or its receptor RANK fail to form lobulo-alveolar mammary structures during pregnancy, resulting in death of newborns. Transplantation and OPGL-rescue experiments in opgl-/- and rank-/- pregnant females showed that OPGL acts directly on RANK-expressing mammary epithelial cells. The effects of OPGL are autonomous to epithelial cells. The mammary gland defect in female opgl-/- mice is characterized by enhanced apoptosis and failures in proliferation and PKB activation in lobulo-alveolar buds that can be reversed by recombinant OPGL treatment. These data provide a novel paradigm in mammary gland development and an evolutionary rationale for hormonal regulation and gender bias of osteoporosis in females.


Assuntos
Proteínas de Transporte/metabolismo , Glândulas Mamárias Animais/crescimento & desenvolvimento , Glândulas Mamárias Animais/metabolismo , Glicoproteínas de Membrana/metabolismo , Proteínas Proto-Oncogênicas , Animais , Remodelação Óssea/efeitos dos fármacos , Remodelação Óssea/fisiologia , Proteínas de Transporte/genética , Divisão Celular/fisiologia , Sobrevivência Celular/fisiologia , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Células Epiteliais/transplante , Feminino , Glicoproteínas/genética , Glicoproteínas/metabolismo , Hormônios Esteroides Gonadais/metabolismo , Hormônios Esteroides Gonadais/farmacologia , Glândulas Mamárias Animais/citologia , Glândulas Mamárias Animais/efeitos dos fármacos , Glicoproteínas de Membrana/genética , Camundongos , Camundongos Knockout , Osteoporose/etiologia , Osteoporose/fisiopatologia , Osteoprotegerina , Fenótipo , Fosforilação , Gravidez/metabolismo , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt , Ligante RANK , Receptor Ativador de Fator Nuclear kappa-B , Receptores Citoplasmáticos e Nucleares/genética , Receptores Citoplasmáticos e Nucleares/metabolismo , Receptores do Fator de Necrose Tumoral
7.
Nature ; 406(6798): 897-902, 2000 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-10972292

RESUMO

Phosphoinositide-3-OH kinases (PI(3)Ks) constitute a family of evolutionarily conserved lipid kinases that regulate a vast array of fundamental cellular responses, including proliferation, transformation, differentiation and protection from apoptosis. PI(3)K-mediated activation of the cell survival kinase PKB/Akt, and negative regulation of PI(3)K signalling by the tumour suppressor PTEN (refs 3, 4) are key regulatory events in tumorigenesis. Thus, a model has arisen that PI(3)Ks promote development of cancers. Here we report that genetic inactivation of the p110gamma catalytic subunit of PI(3)Kgamma (ref. 8) leads to development of invasive colorectal adenocarcinomas in mice. In humans, p110gamma protein expression is lost in primary colorectal adenocarcinomas from patients and in colon cancer cell lines. Overexpression of wild-type or kinase-dead p110gamma in human colon cancer cells with mutations of the tumour suppressors APC and p53, or the oncogenes beta-catenin and Ki-ras, suppressed tumorigenesis. Thus, loss of p110gamma in mice leads to spontaneous, malignant epithelial tumours in the colorectum and p110gamma can block the growth of human colon cancer cells.


Assuntos
Neoplasias Colorretais/enzimologia , Fosfatidilinositol 3-Quinases/metabolismo , Adenocarcinoma/enzimologia , Adenocarcinoma/genética , Animais , Carcinoma/enzimologia , Carcinoma/genética , Domínio Catalítico/genética , Proteínas de Ciclo Celular/biossíntese , Mapeamento Cromossômico , Cromossomos Humanos Par 7 , Neoplasias Colorretais/genética , Humanos , Longevidade , Camundongos , Camundongos Nus , Dados de Sequência Molecular , Fosfatidilinositol 3-Quinases/genética , Biossíntese de Proteínas , Células Tumorais Cultivadas
8.
Cell Mol Life Sci ; 57(1): 77-95, 2000 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-10949582

RESUMO

Female reproductive tissues possess a unique ability to accommodate a remarkable amount of cell turnover and extracellular matrix (ECM) remodeling following puberty. Cellular structures within ovary, uterus, and mammary tissue not only change cyclically in response to ovarian hormones but also undergo differentiation during pregnancy, and eventually revert to that resembling the pre-pregnant stage. Cell proliferation, apoptosis, invasion, and differentiation are integral cellular processes that are precisely regulated in reproductive tissues, but become dysregulated in pathologies such as cancer. Explicit reorganization of ECM and basement membranes is also critical to preserve the form and function of these tissues. Here we review the evidence that coordinated spatiotemporal expression patterns of matrix metalloproteinase (MMP) genes and their tissue inhibitors (TIMPs) are important in cell and ECM turnover of the ovary, uterus, and mammary tissues. We discuss how perturbation in these gene families may impact the biology of these reproductive tissues and the factors implicated in the control of MMP and TIMP gene expression. The observed trends in MMP and TIMP expression involved in ovarian and mammary carcinomas are also presented.


Assuntos
Matriz Extracelular/enzimologia , Matriz Extracelular/metabolismo , Inibidores de Metaloproteinases de Matriz , Metaloproteinases da Matriz/metabolismo , Reprodução/fisiologia , Animais , Mama/citologia , Mama/enzimologia , Mama/patologia , Mama/fisiologia , Feminino , Regulação Enzimológica da Expressão Gênica , Humanos , Metaloproteinases da Matriz/genética , Morfogênese , Neoplasias/enzimologia , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patologia , Ovário/citologia , Ovário/enzimologia , Ovário/patologia , Ovário/fisiologia , Gravidez , Inibidores Teciduais de Metaloproteinases/genética , Inibidores Teciduais de Metaloproteinases/metabolismo , Útero/citologia , Útero/enzimologia , Útero/fisiologia
9.
Nat Med ; 6(3): 306-12, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10700233

RESUMO

Golgi beta1,6N-acetylglucosaminyltransferase V (MGAT5) is required in the biosynthesis of beta1,6GlcNAc-branched N-linked glycans attached to cell surface and secreted glycoproteins. Amounts of MGAT5 glycan products are commonly increased in malignancies, and correlate with disease progression. To study the functions of these N-glycans in development and disease, we generated mice deficient in Mgat5 by targeted gene mutation. These Mgat5-/- mice lacked Mgat5 products and appeared normal, but differed in their responses to certain extrinsic conditions. Mammary tumor growth and metastases induced by the polyomavirus middle T oncogene was considerably less in Mgat5-/- mice than in transgenic littermates expressing Mgat5. Furthermore, Mgat5 glycan products stimulated membrane ruffling and phosphatidylinositol 3 kinase-protein kinase B activation, fueling a positive feedback loop that amplified oncogene signaling and tumor growth in vivo. Our results indicate that inhibitors of MGAT5 might be useful in the treatment of malignancies by targeting their dependency on focal adhesion signaling for growth and metastasis.


Assuntos
Neoplasias Mamárias Experimentais/patologia , Neoplasias Mamárias Experimentais/prevenção & controle , N-Acetilglucosaminiltransferases/metabolismo , Polissacarídeos/biossíntese , Animais , Sequência de Carboidratos , Carcinoma/enzimologia , Carcinoma/patologia , Cruzamentos Genéticos , Feminino , Fibroadenoma/enzimologia , Fibroadenoma/patologia , Complexo de Golgi/metabolismo , Complexo de Golgi/patologia , Humanos , Masculino , Camundongos , Camundongos Knockout , Dados de Sequência Molecular , Mutagênese , N-Acetilglucosaminiltransferases/deficiência , N-Acetilglucosaminiltransferases/genética , Metástase Neoplásica , Polissacarídeos/química , Proteínas Recombinantes/metabolismo
10.
Dev Biol ; 211(2): 238-54, 1999 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-10395785

RESUMO

The dynamic process of mammary ductal morphogenesis depends on regulated epithelial proliferation and extracellular matrix (ECM) turnover. Epithelial cell-matrix contact closely dictates epithelial proliferation, differentiation, and survival. Despite the fact that tissue inhibitors of metalloproteinases (Timps) regulate ECM turnover, their function in mammary morphogenesis is unknown. We have delineated the spatiotemporal expression of all Timps (Timp-1 to Timp-4) during discrete phases of murine mammary development. Timp mRNAs were abundant in mammary tissue, each displaying differential expression patterns with predominant localization in luminal epithelial cells. Timp-1 mRNA was unique in that its expression was limited to the stage at which epithelial proliferation was high. To assess whether Timp-1 promotes or inhibits epithelial cell proliferation we manipulated mammary Timp-1 levels, genetically and biochemically. Down-regulation of epithelial-derived Timp-1 in transgenic mice, by mouse mammary tumor virus promoter-directed Timp-1 antisense RNA expression, led to augmented ductal expansion and increased number of ducts (P < 0.004). In these transgenics the integrity of basement membrane surrounding epithelial ducts, as visualized by laminin-specific immunostaining, was breached. In contrast to these mice, ductal expansion was markedly attenuated in the proximity of implanted recombinant Timp-1-releasing pellets (rTIMP-1), without an increase in basement membrane deposition around migrating terminal end buds. Epithelial proliferation and apoptosis were measured to determine the basis of altered ductal expansion. Luminal epithelial proliferation was increased by 55% (P < 0.02) in Timp-1-reduced transgenic mammary tissue and, conversely, decreased by 38% (P < 0.02) in terminal end buds by implanted rTIMP-1. Epithelial apoptosis was minimal and remained unaffected by Timp-1 manipulations. We conclude that Timps have an integral function in mammary morphogenesis and that Timp-1 regulates mammary epithelial proliferation in vivo, at least in part by maintaining basement membrane integrity.


Assuntos
Células Epiteliais/fisiologia , Glândulas Mamárias Animais/embriologia , Inibidor Tecidual de Metaloproteinase-1/fisiologia , Animais , Células Epiteliais/citologia , Feminino , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Imuno-Histoquímica , Glândulas Mamárias Animais/fisiologia , Camundongos , Morfogênese , RNA Mensageiro/análise
11.
Plast Reconstr Surg ; 103(1): 197-201, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9915184

RESUMO

The vermilion myomucosal advancement flap was successfully used to reconstruct the oral commissure for a wide range of deformities in three patients with facial gunshot wounds. In one case, a delayed cross lip flap was later used to restore the philtrum of the upper lip, despite the fact that the cutaneous perforating vessels of the cross lip flap had previously been divided.


Assuntos
Lábio/cirurgia , Boca/lesões , Boca/cirurgia , Retalhos Cirúrgicos , Ferimentos por Arma de Fogo/cirurgia , Adolescente , Adulto , Pré-Escolar , Contratura/cirurgia , Humanos , Lábio/lesões , Masculino , Cicatrização
12.
Ann Emerg Med ; 32(3 Pt 1): 329-33, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9737495

RESUMO

STUDY OBJECTIVE: We sought to compare the effects of hypertonic sodium chloride solution (HTS), sodium bicarbonate solution, and hyperventilation (HV) on severe tricyclic antidepressant (TCA) toxicity in a swine model. METHODS: Twenty-four mixed-breed, domestic swine of either sex were given an intravenous infusion of nortriptyline (NT) until development of both a QRS duration longer than 120 ms and a systolic blood pressure (SBP) less than or equal to 50 mm Hg. Animals were randomly assigned to 1 of 4 groups. On reaching toxicity, the control group received 10 mL/kg of 5% dextrose in water (D5W); the HTS group received 10 mL/kg of 7.5% NaCl solution (15 mEq Na+/kg); the NaHCO3 group received 3 mEq/kg of 8.4% sodium bicarbonate solution followed by enough D5W solution to equal 10 mL/kg of total volume; and the HV group was mechanically hyperventilated to maintain arterial pH between 7.50 and 7.60 and given 10 mL/kg of D5W. RESULTS: The mean SBP 10 minutes after treatment was 54+/-18 mm Hg in the control group, 134+/-21 mm Hg in the HTS group, 85+/-19 mm Hg in the NaHCO3 group, and 60+/-12 mm Hg in the HV group (P<.05). Mean QRS duration 10 minutes after treatment was 144+/-38 ms in the control group, 80+/-14 ms in the HTS group, 105+/-38 ms in the NaHCO3 group, and 125+/-46 ms in the HV group (P<.05). CONCLUSION: In this model of TCA, toxicity HTS was more effective than sodium bicarbonate. Hyperventilation had little effect. Sodium loading may be the most important factor in reversing TCA toxicity.


Assuntos
Antidepressivos Tricíclicos/efeitos adversos , Nortriptilina/efeitos adversos , Respiração Artificial , Solução Salina Hipertônica/uso terapêutico , Bicarbonato de Sódio/uso terapêutico , Animais , Pressão Sanguínea/efeitos dos fármacos , Soluções Tampão , Modelos Animais de Doenças , Eletrocardiografia/efeitos dos fármacos , Feminino , Hidratação , Glucose/administração & dosagem , Glucose/uso terapêutico , Concentração de Íons de Hidrogênio , Injeções Intravenosas , Masculino , Distribuição Aleatória , Respiração Artificial/métodos , Solução Salina Hipertônica/administração & dosagem , Sódio/sangue , Sódio/uso terapêutico , Bicarbonato de Sódio/administração & dosagem , Suínos , Taquicardia Ventricular/induzido quimicamente , Taquicardia Ventricular/tratamento farmacológico
13.
Oncogene ; 16(18): 2419-23, 1998 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-9620561

RESUMO

Within the tumor-stromal microenvironment a disrupted balance between matrix metalloproteinases (MMPs) and their inhibitors compromises the integrity of the extracellular matrix and promotes malignancy. Tissue inhibitors of metalloproteinases (TIMPs) have been linked to tumor suppression in studies of genetically altered tissue culture cells and in analyses of clinical specimens in situ. We generated transgenic mice as a model system to test the relationship between TIMP-1 levels in a host organ and susceptibility to experimentally targeted metastasis. Ectopically overexpressed TIMP-1 in the brain resulted in a tissue microenvironment with elevated protein levels of this natural MMP inhibitor. Metastatic challenge provided by lacZ-tagged fibrosarcoma cells permitted high-resolution analysis of metastatic load and pattern. We found that elevated host TIMP-1 imposed resistance to experimental metastasis of fibrosarcoma: In TIMP-1 overexpressing mice, brain metastases were significantly reduced by 75% compared to wild-type littermates. Our findings demonstrate that ectopic TIMP-1 expression efficiently exerts a suppressive effect on metastasizing tumor cells.


Assuntos
Neoplasias Encefálicas/secundário , Fibrossarcoma/secundário , Metástase Neoplásica/genética , Inibidor Tecidual de Metaloproteinase-1/biossíntese , Animais , Imunidade Inata , Camundongos , Camundongos Transgênicos , Inibidor Tecidual de Metaloproteinase-1/genética
14.
Blood ; 90(5): 1993-2000, 1997 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-9292534

RESUMO

The concept of tumor suppression by tissue inhibitor of metalloproteinases (TIMPs) has evolved primarily from studies of genetically modulated tumor cells. The next step is to focus on the host and assess the protective potential of host TIMP-1 on primary tumor growth and metastasis. We generated two transgenic mouse lines with altered Timp-1 expression in skin and liver: one overexpressed Timp-1 (Timp-1(high)), and the other had antisense RNA-mediated Timp-1 reduction (Timp-1(low)). ESbL-lacZ T-lymphoma cells provided the tumor challenge, as they form primary tumors upon intradermal injection with spontaneous metastasis to liver. Metastases were examined in X-Gal-stained whole-organ mounts. Timp-1 overexpression inhibited intradermal tumor growth and spontaneous metastasis, leading to prolonged survival of the mice. The opposite effects occurred in Timp-1(low) mice, leading to shorter host survival. Experimental metastasis assays showed that Timp-1-compromised livers in Timp-1(low) mice showed at least a doubling of metastatic foci and numerous additional micrometastases, indicative of increased host susceptibility. However, Timp-1(high) mouse livers showed an unaltered metastatic load in the experimental metastasis assay. In conclusion, these data demonstrate that Timp-1 levels within a tissue predetermine the development and progression of T-cell lymphoma.


Assuntos
Regulação Neoplásica da Expressão Gênica , Glicoproteínas/genética , Linfoma de Células T/patologia , Neoplasias Experimentais/patologia , Animais , Divisão Celular/genética , Linfoma de Células T/genética , Camundongos , Camundongos Transgênicos , Metástase Neoplásica/genética , Neoplasias Experimentais/genética , Inibidores Teciduais de Metaloproteinases
15.
Plast Reconstr Surg ; 99(4): 1172-5, 1997 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9091923

RESUMO

A composite chondrocutaneous advancement flap is described for the reconstruction of full thickness marginal defects of the ear. It has been used successfully in two patients to reconstruct defects involving the helix and scapha and is recommended for defects whose wound dimensions exceed the limitations of both wedge excision and Antia and Buch's chondrocutaneous flap.


Assuntos
Orelha Externa/cirurgia , Retalhos Cirúrgicos/métodos , Idoso , Idoso de 80 Anos ou mais , Carcinoma Basocelular/cirurgia , Neoplasias da Orelha/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade
16.
Prehosp Disaster Med ; 11(2): 144-6, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-10159740

RESUMO

Adenosine (Adenocard) is an endogenous purine nucleoside that has been approved recently for intravenous treatment of paroxysmal supraventricular tachycardia. With a serum half-life of 10 seconds, reported side effects including facial flushing, dyspnea, and chest pressure are common, but very transient. An elderly woman who received adenosine for paroxysmal supraventricular tachycardia had a prolonged anaphylactoid reaction that required pharmacological treatment. This is the first reported case of a prolonged anaphylactoid reaction to adenosine.


Assuntos
Adenosina/efeitos adversos , Anafilaxia/induzido quimicamente , Adenosina/uso terapêutico , Feminino , Humanos , Pessoa de Meia-Idade , Taquicardia Paroxística/tratamento farmacológico , Taquicardia Supraventricular/tratamento farmacológico
17.
Cancer Metastasis Rev ; 14(2): 97-111, 1995 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7554034

RESUMO

The extracellular matrix (ECM) acts as both a structural scaffold and an informational medium. Its dynamic status is determined by cells that secrete its constituent molecules and, in most cases, also secrete enzymes that catalyze degradation of these molecules. A stasis between ECM degrading enzymes and their inhibitors maintains the integrity of the matrix. While controlled ECM remodelling is fundamental to several normal processes, uncontrolled disruption underlies diverse pathological conditions. Transgenic mice with specific modulations or a total lack of expression of certain metalloproteinases, serine proteinases or their inhibitors have been generated to elucidate endogenous expression patterns, identify regulatory elements of these genes, and study the physiological consequences of their deregulated expression. With these models we enhance our understanding of the role of proteinases and their inhibitors in diverse normal processes and pathologies including mammary gland development, hemostasis, emphysema and cancer.


Assuntos
Matriz Extracelular/metabolismo , Metaloendopeptidases/metabolismo , Camundongos Transgênicos , Inibidores de Proteases/metabolismo , Serina Endopeptidases/metabolismo , Animais , Metaloendopeptidases/antagonistas & inibidores , Camundongos , Camundongos Knockout , Inibidores de Serina Proteinase/metabolismo
18.
Growth Regul ; 1(3): 105-9, 1991 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-1842566

RESUMO

Epidermal growth factor exerts potent receptor-mediated mitogenic effects on a variety of target cells in vitro, but its importance in normal organ development is not yet fully understood. We report that the specific high-affinity receptors for EGF/TGF-Alpha increase dramatically in late gestational rat kidney (from 2.3% at 16 days gestation to 6.4% at term) and then fall toward basal adult levels (< 1% binding) during the first week of post-natal life. This post-natal fall-off in EGF binding corresponds temporally to the period when replication of rat kidney DNA begins to slow (4-7 days of post-natal life). EGF mRNA is not detectable in rat kidney by Northern analysis until the second week of post-natal life, but high levels of transforming growth factor-alpha are demonstrable by specific radioimmunoassay in extracts of fetal kidney (52.2 +/- 8.2 pmoles/gram kidney) and amniotic fluid (4.49 +/- 0.75 pmoles/ml). We speculate that induction of EGF-receptors in fetal rat kidney may confer responsiveness to local transforming growth factor-alpha and dictate the rate of hyperplastic renal growth in the perinatal period.


Assuntos
Receptores ErbB/metabolismo , Rim/embriologia , Fator de Crescimento Transformador alfa/fisiologia , Líquido Amniótico/metabolismo , Animais , Northern Blotting , DNA/metabolismo , Fator de Crescimento Epidérmico/genética , Fator de Crescimento Epidérmico/metabolismo , Idade Gestacional , Rim/crescimento & desenvolvimento , Rim/metabolismo , Tamanho do Órgão , RNA Mensageiro/metabolismo , Ratos
19.
Mol Cell Endocrinol ; 77(1-3): 199-206, 1991 May.
Artigo em Inglês | MEDLINE | ID: mdl-1726155

RESUMO

Beginning at the fifth week of fetal life, successive generations of individual nephrons are induced by contact between metanephric mesenchyme and ureteric bud. Following phenotypic transformation, cells of each primitive renal vesicle undergo a phase of rapid cell division. In order to identify genes which might regulate nephron development in man, we screened adult and fetal kidney RNA for expression of a panel of growth-related genes. Among the genes which were expressed at higher levels in fetal kidney was the epidermal growth factor (EGF) receptor. There is controversy as to the most likely physiologic EGF receptor ligand in fetal kidney; we were able to identify a transcript for transforming growth factor-alpha (TGF-alpha) but not EGF on Northern blots of fetal kidney RNA. Since the abundance of TGF-alpha mRNA is low, we confirmed its presence by polymerase chain reaction amplification. Using specific radioimmunoassays, we also provide direct evidence for TGF-alpha but not EGF peptide in extracts of fetal kidney and mid-gestational amniotic fluid. We suggest that TGF-alpha/EGF receptor interactions may serve an important function in development of human fetal kidney.


Assuntos
Receptores ErbB/biossíntese , Rim/metabolismo , Fator de Crescimento Transformador alfa/biossíntese , Sequência de Bases , Northern Blotting , Southern Blotting , DNA , Sondas de DNA , Receptores ErbB/genética , Receptores ErbB/metabolismo , Expressão Gênica , Humanos , Rim/embriologia , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , RNA/metabolismo , Fator de Crescimento Transformador alfa/genética , Fator de Crescimento Transformador alfa/metabolismo
20.
AJR Am J Roentgenol ; 155(2): 333-5, 1990 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-2115262

RESUMO

We reviewed the radiographs of 14 patients who had cervical osteomyelitis and were IV heroin users. Eleven were men and three were women. Their age range was 33-48 years (mean, 39 years). Eleven regularly used the jugular vein access, and three alternated between the jugular and femoral veins. Initial radiographs of the cervical spine in 13 patients showed destruction of two or more vertebral bodies and the adjacent intervertebral disk, as well as a prevertebral soft-tissue mass. In one patient, findings on initial radiographs were normal, but marked destruction at two contiguous intervertebral levels and a large prevertebral abscess were identified 2 weeks later. All the patients had positive results on cultures of joint aspirates or bone biopsy materials (10 patients) or blood (four patients). Ten grew Staphylococcus aureus; two, Staphylococcus epidermidis; one, Streptococcus viridans; and one, Pseudomonas aeruginosa. CT in nine patients showed inflammatory reaction adjacent to the carotid sheath resulting from the repeated jugular injections and delineated the extent of prevertebral abscess and bone destruction. Scintigrams were of minimal value in establishing the diagnosis. Advanced vertebral body destruction, disk space infection, prevertebral abscess, and anterior cervical inflammatory reaction appear to be typical findings on radiographs in heroin abusers with cervical osteomyelitis.


Assuntos
Vértebras Cervicais/diagnóstico por imagem , Heroína , Osteomielite/diagnóstico por imagem , Abuso de Substâncias por Via Intravenosa/complicações , Adulto , Feminino , Veia Femoral , Humanos , Veias Jugulares , Masculino , Pessoa de Meia-Idade , Osteomielite/etiologia , Radiografia
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