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1.
J Intern Med ; 283(6): 558-567, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29532534

RESUMO

AIM: Hospitalization for heart failure amongst younger men has increased. The reason for this is unknown but it coincides with the obesity epidemic. The aim of this study was to evaluate the association between childhood BMI (Body Mass Index) and BMI change during puberty for risk of adult heart failure in men. METHODS: Using the BMI Epidemiology Study (BEST), a population-based study in Gothenburg, Sweden, we collected information on childhood BMI at age 8 years and BMI change during puberty (BMI at age 20 - BMI at 8) for men born 1945-1961, followed until December 2013 (n = 37 670). BMI was collected from paediatric growth charts and mandatory military conscription tests. Information on heart failure was retrieved from high-quality national registers (342 first hospitalizations for heart failure). RESULTS: BMI change during puberty was independently of childhood BMI associated with risk of heart failure in a nonlinear J-shaped manner. Subjects in the upper quartile of BMI change during puberty (Q4) had more than twofold increased risk of heart failure compared with subjects in Q1 [HR (Hazard Ratio) = 2.29, 95% CI (Confidence Interval) 1.68-3.12]. Childhood BMI was not independently associated with risk of heart failure. Boys developing overweight during puberty (HR 3.14; 95% CI 2.25-4.38) but not boys with childhood overweight that normalized during puberty (HR 1.12, 95% CI 0.63-2.00) had increased risk of heart failure compared with boys without childhood or young adult overweight. CONCLUSION: BMI change during puberty is a novel risk factor for adult heart failure in men.


Assuntos
Insuficiência Cardíaca/etiologia , Puberdade/fisiologia , Adulto , Peso ao Nascer/fisiologia , Índice de Massa Corporal , Seguimentos , Insuficiência Cardíaca/epidemiologia , Hospitalização/estatística & dados numéricos , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Obesidade Infantil/epidemiologia , Prognóstico , Fatores de Risco , Suécia/epidemiologia , Adulto Jovem
2.
Int J Obes (Lond) ; 41(5): 807-812, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28119533

RESUMO

BACKGROUND/OBJECTIVES: Childhood obesity increases the risk for adult obesity and diseases. The aim of this study was to investigate secular changes of childhood body mass index (BMI), overweight and obesity in boys born during 1946-2006, using the population-based BMI Epidemiology STudy (BEST) cohort in Gothenburg, Sweden. SUBJECTS/METHODS: We collected height and weight from archived school health records for boys born every 5 years 1946-2006 (birth cohort 1946 n=1584, each birth cohort 1951-2006 n=425). Childhood BMI at 8 years of age was obtained for all the participants. RESULTS: Childhood BMI increased 0.18 kg m-2 (95% confidence interval: 0.16-0.20) per decade increase in birth year, during 1946-2006. The increase was significant from birth year 1971, peaked 1991 and was then followed by a stabilization or tendency to a reduction. Next, we aimed to thoroughly explore the trend after birth year 1991 and therefore expanded birth cohorts 1991 (n=1566), 2001 (n=6478) and 2006 (n=6515). Importantly, decreases in mean BMI (P<0.01), prevalences of overweight (P<0.01) and obesity (P<0.05) were observed after birth year 1991. For boys born in Sweden and with parents born in Sweden, a substantial reduction in the prevalences of overweight (-28.6%, P<0.001) and obesity (-44.3%, P<0.001) were observed between birth year 1991 and birth year 2006. CONCLUSIONS: This long-term study captures both the rise and the recent decline of childhood obesity. As childhood obesity is strongly associated with subsequent adult obesity, we anticipate a similar reduction in adult obesity during the coming decades in Swedish men.


Assuntos
Obesidade Infantil/epidemiologia , Saúde Pública , Análise de Variância , Índice de Massa Corporal , Criança , Estudos de Coortes , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Masculino , Obesidade Infantil/prevenção & controle , Vigilância da População , Prevalência , Suécia/epidemiologia , Fatores de Tempo
3.
BJOG ; 124(6): 880-889, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28190289

RESUMO

BACKGROUND: It has been argued that salpingectomy would reduce the risk of epithelial ovarian cancer (EOC), based on the theory of the tube being the site of origin. OBJECTIVES: To conduct a systematic review of 'salpingectomy' associated with ovarian cancer risk and 'salpingectomy with concomitant hysterectomy' on outcomes of complications including endocrine function. SEARCH STRATEGY: A comprehensive search was conducted in PubMed, Embase, and the Cochrane library. SELECTION CRITERIA: Original studies and systematic reviews were eligible. DATA COLLECTION AND ANALYSIS: Each article was quality assessed. Data were extracted and, when possible, pooled in meta-analyses. The certainty of evidence across studies was evaluated using GRADE. MAIN RESULTS: Of 844 articles found, 11 were included. No study evaluated risk reduction for EOC after salpingectomy in conjunction with hysterectomy. Two retrospective studies reported a reduced ovarian cancer risk after indicated salpingectomy, compared with no surgery: adjusted hazard ratio 0.65 (95% confidence interval, 95% CI 0.52-0.81) and adjusted odds ratio 0.58 (95% CI 0.36-0.95). Complications did not differ between groups with or without salpingectomy, but were non-systematically reported. Ovarian endocrine function, measured with surrogate outcomes, did not differ at short-term follow-up in randomised or observational studies. The certainty of evidence was very low or low for all outcomes. CONCLUSIONS: There is currently insufficient evidence to state that opportunistic salpingectomy reduces the risk of EOC. The impact on long-term endocrine function is unknown. The heterogeneity in results and identified knowledge gaps stress the need for a prospective trial. TWEETABLE ABSTRACT: Insufficient evidence for prophylactic removal of the fallopian tubes for risk reduction of ovarian cancer.


Assuntos
Carcinoma Epitelial do Ovário/prevenção & controle , Histerectomia/métodos , Neoplasias Ovarianas/prevenção & controle , Procedimentos Cirúrgicos Profiláticos/métodos , Salpingectomia/métodos , Adulto , Carcinoma Epitelial do Ovário/etiologia , Feminino , Humanos , Pessoa de Meia-Idade , Razão de Chances , Neoplasias Ovarianas/etiologia , Fatores de Risco , Resultado do Tratamento
4.
J Intern Med ; 280(4): 398-406, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27038007

RESUMO

BACKGROUND: It has been suggested that osteoblasts are involved in the regulation of haematopoietic stem cells. Whether osteocalcin, which is derived from osteoblasts and is metabolically active, influences blood haemoglobin (Hb) levels is not known. OBJECTIVE: To determine whether plasma osteocalcin is a determinant of Hb in elderly men. METHODS: A total of 993 men (mean age 75.3 ± 3.2 years) participated in the population-based MrOS (osteoporotic fractures in men) study. Plasma osteocalcin concentration was evaluated in relation to Hb and adjustments were made for potential confounders (i.e. age, body mass index, erythropoietin, total oestradiol, fasting insulin, adiponectin, ferritin and cystatin C). RESULTS: Hb correlated (age adjusted) negatively with osteocalcin in the total study group (r = -0.12, P < 0.001) as well as in the subgroup of nondiabetic men (r = -0.16, P < 0.001). In nondiabetic men with higher osteocalcin levels, it was more likely that Hb would be in the lowest quartile (odds ratio per SD decrease in osteocalcin 1.32, 95% confidence interval 1.13-1.53). Quartiles of Hb were negatively associated (age adjusted) with osteocalcin (P < 0.001). Anaemic men (47/812) (Hb <130 g L(-1) ) had significantly higher mean osteocalcin levels than nonanaemic men (33.9 vs. 27.1 µg L(-1) , P < 0.001). In multiple stepwise linear regression analyses (adjusted for age, body mass index, total oestradiol, adiponectin, erythropoietin, fasting insulin, cystatin C, leptin, ferritin and holotranscobalamin), osteocalcin was an independent predictor of Hb concentration in nondiabetic men (P < 0.05). CONCLUSIONS: These data add further support to the evidence indicating that the bone-specific protein osteocalcin has several endocrine functions targeting the pancreas, testes, adipocytes, brain. An additional novel finding is that osteocalcin may also have a paracrine function as a regulator of haematopoiesis.


Assuntos
Hematopoese/fisiologia , Hemoglobinas/metabolismo , Osteocalcina/sangue , Fatores Etários , Idoso , Anemia/sangue , Humanos , Contagem de Leucócitos , Masculino , Síndrome Metabólica/sangue , Contagem de Plaquetas , Estudos Prospectivos , Análise de Regressão
5.
Proc Natl Acad Sci U S A ; 108(15): 6288-93, 2011 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-21444817

RESUMO

The bone-sparing effect of estrogen is primarily mediated via estrogen receptor-α (ERα), which stimulates target gene transcription through two activation functions (AFs), AF-1 in the N-terminal and AF-2 in the ligand binding domain. To evaluate the role of ERα AF-1 and ERα AF-2 for the effects of estrogen in bone in vivo, we analyzed mouse models lacking the entire ERα protein (ERα(-/-)), ERα AF-1 (ERαAF-1(0)), or ERα AF-2 (ERαAF-2(0)). Estradiol (E2) treatment increased the amount of both trabecular and cortical bone in ovariectomized (OVX) WT mice. Neither the trabecular nor the cortical bone responded to E2 treatment in OVX ERα(-/-) or OVX ERαAF-2(0) mice. OVX ERαAF-1(0) mice displayed a normal E2 response in cortical bone but no E2 response in trabecular bone. Although E2 treatment increased the uterine and liver weights and reduced the thymus weight in OVX WT mice, no effect was seen on these parameters in OVX ERα(-/-) or OVX ERαAF-2(0) mice. The effect of E2 in OVX ERαAF-1(0) mice was tissue-dependent, with no or weak E2 response on thymus and uterine weights but a normal response on liver weight. In conclusion, ERα AF-2 is required for the estrogenic effects on all parameters evaluated, whereas the role of ERα AF-1 is tissue-specific, with a crucial role in trabecular bone and uterus but not cortical bone. Selective ER modulators stimulating ERα with minimal activation of ERα AF-1 could retain beneficial actions in cortical bone, constituting 80% of the skeleton, while minimizing effects on reproductive organs.


Assuntos
Osso e Ossos/fisiologia , Receptor alfa de Estrogênio/fisiologia , Estrogênios/fisiologia , Animais , Densidade Óssea , Osso e Ossos/diagnóstico por imagem , Osso e Ossos/efeitos dos fármacos , Estradiol/farmacologia , Receptor alfa de Estrogênio/genética , Estrogênios/farmacologia , Feminino , Camundongos , Camundongos Mutantes , Tamanho do Órgão , Radiografia , Moduladores Seletivos de Receptor Estrogênico/farmacologia , Timo/anatomia & histologia , Timo/efeitos dos fármacos , Timo/fisiologia , Ativação Transcricional , Útero/anatomia & histologia , Útero/efeitos dos fármacos , Útero/fisiologia
6.
Cancer Res ; 60(24): 6832-5, 2000 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-11156374

RESUMO

Extraskeletal myxoid chondrosarcomas (EMCs) are characterized by recurrent t(9;22) or t(9;17) translocations resulting in fusions of the NH2-terminal transactivation domains of EWS or TAF2N to the entire TEC protein. We report here an EMC with a novel translocation t(9; 15)(q22;q21) and a third type of TEC-containing fusion gene. The chimeric transcript encodes a protein in which the first 108 amino acids of the NH2-terminus of the basic helix-loop-helix (bHLH) protein TCF12 is linked to the entire TEC protein. The translocation separates the NH2-terminal domain of TCF12 from the bHLH domain as well as from a potential leucine zipper domain located immediately downstream of the breakpoint. These results demonstrate that the NH2-terminal transactivation domains of EWS or TAF2N are not unique in their ability to convert the TEC protein into an oncogenically active fusion protein, and that they may be replaced by a domain from a bHLH protein that presumably endows the fusion protein with similar functions.


Assuntos
Condrossarcoma/genética , Condrossarcoma/metabolismo , Cromossomos Humanos Par 15 , Cromossomos Humanos Par 9 , Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/metabolismo , Neoplasias Musculares/genética , Neoplasias Musculares/metabolismo , Proteínas do Tecido Nervoso , Proteínas Nucleares/química , Proteínas Nucleares/metabolismo , Fatores de Transcrição/química , Translocação Genética , Idoso , Sequência de Aminoácidos , Sequência de Bases , Fatores de Transcrição Hélice-Alça-Hélice Básicos , Células Cultivadas , Bandeamento Cromossômico , Citoplasma/metabolismo , Sequências Hélice-Alça-Hélice , Humanos , Masculino , Dados de Sequência Molecular , Ligação Proteica , Estrutura Terciária de Proteína , Receptores de Esteroides , Receptores dos Hormônios Tireóideos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA , Fatores de Transcrição/metabolismo
7.
Oncogene ; 19(37): 4298-301, 2000 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-10980604

RESUMO

The EWS/FLI-1 fusion gene is characteristic of most cases of Ewing's sarcoma and has been shown to be crucial for tumor transformation and cell growth. In this study we demonstrate a drastic down-regulation of the EWS/FLI-1 protein, and a growth arrest, following serum depletion of Ewing's sarcoma cells. This indicates that growth factor circuits may be involved in regulation of the fusion gene product. Of four different growth factors tested, basic fibroblast growth factor (bFGF) was found to be of particular significance. In fact, upon treatment of serum-depleted cells with bFGF, expression of the EWS/FLI-1 protein and growth of the Ewing's sarcoma cells were restored. In addition, a bFGF-neutralizing antibody, which was confirmed to inhibit FGF receptor (FGFR) phosphorylation, caused down-regulation of EWS/FLI-1. Experiments using specific cell cycle blockers (thymidine and colcemide) suggest that EWS/FLI-1 is directly linked to bFGF stimulation, and not indirectly to cell proliferation. We also demonstrated expression of FGFRs in several tumor samples of Ewing's sarcoma. Taken together, our data suggest that expression of FGFR is a common feature of Ewing's sarcoma and, in particular, that the bFGF pathway may be important for the maintenance of a malignant phenotype of Ewing's sarcoma cells through up-regulating the EWS/FLI-1 protein. Oncogene (2000) 19, 4298 - 4301


Assuntos
Neoplasias Ósseas/patologia , Fator 2 de Crescimento de Fibroblastos/fisiologia , Regulação Neoplásica da Expressão Gênica/fisiologia , Proteínas de Neoplasias/fisiologia , Proteínas de Fusão Oncogênica/biossíntese , Sarcoma de Ewing/patologia , Fatores de Transcrição/biossíntese , Adenocarcinoma/patologia , Anticorpos Monoclonais/farmacologia , Neoplasias Ósseas/metabolismo , Ciclo Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Cromossomos Humanos Par 11/genética , Cromossomos Humanos Par 11/ultraestrutura , Cromossomos Humanos Par 22/genética , Cromossomos Humanos Par 22/ultraestrutura , Meios de Cultura Livres de Soro , Demecolcina/farmacologia , Sinergismo Farmacológico , Fator de Crescimento Epidérmico/farmacologia , Fator 2 de Crescimento de Fibroblastos/antagonistas & inibidores , Fator 2 de Crescimento de Fibroblastos/imunologia , Fibroblastos/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Fator de Crescimento Insulin-Like I/farmacologia , Masculino , Proteínas de Neoplasias/biossíntese , Proteínas de Neoplasias/genética , Proteínas de Fusão Oncogênica/genética , Fator de Crescimento Derivado de Plaquetas/farmacologia , Neoplasias da Próstata/patologia , Proteína Proto-Oncogênica c-fli-1 , Proteína EWS de Ligação a RNA , Receptores de Fatores de Crescimento de Fibroblastos/efeitos dos fármacos , Receptores de Fatores de Crescimento de Fibroblastos/fisiologia , Sarcoma de Ewing/metabolismo , Timidina/farmacologia , Fatores de Transcrição/genética , Translocação Genética , Células Tumorais Cultivadas/efeitos dos fármacos , Células Tumorais Cultivadas/metabolismo
8.
Mol Endocrinol ; 15(12): 2115-28, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11731613

RESUMO

Thyroid hormone governs a diverse repertoire of physiological functions through receptors encoded in the receptor genes alpha and beta, which each generate variant proteins. In mammals, the alpha gene generates, in addition to the normal receptor TRalpha1, a non-hormone-binding variant TRalpha2 whose exact function is unclear. Here, we present the phenotype associated with the targeted ablation of TRalpha2 expression. Selective ablation of TRalpha2 resulted in an inevitable, concomitant overexpression of TRalpha1. Both TRalpha2 +/- and -/- mice show a complex phenotype with low levels of free T3 and free T4, and have inappropriately normal levels of TSH. The thyroid glands exhibit mild morphological signs of dysfunction and respond poorly to TSH, suggesting that the genetic changes affect the ability of the gland to release thyroid hormones. However, the phenotype of the mutant mice also has features of hyperthyroidism, including decreased body weight, elevated heart rate, and a raised body temperature. Furthermore, TRalpha2-/- and TRalpha2+/- mice are obese and exhibit skeletal alterations, associated with a late-onset growth retardation. The results thus suggest that the overexpression of TRalpha1 and the concomitant decrease in TRalpha2 expression lead to a mixed hyper- and hypothyroid phenotype, dependent on the tissue studied. The phenotypes suggest that the balance of TRalpha1:TRalpha2 expressed from the TRalpha gene provides an additional level of tuning the control of growth and homeostasis in mammalian species.


Assuntos
Proteínas de Ligação a DNA/fisiologia , Regulação da Expressão Gênica/fisiologia , Hipertireoidismo/genética , Hipotireoidismo/genética , Receptores Citoplasmáticos e Nucleares/fisiologia , Receptores dos Hormônios Tireóideos , Animais , Northern Blotting , Composição Corporal , Densidade Óssea , Cruzamentos Genéticos , Proteínas de Ligação a DNA/biossíntese , Proteínas de Ligação a DNA/genética , Feminino , Histocitoquímica , Hipertireoidismo/metabolismo , Hipotireoidismo/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Fenótipo , RNA/química , RNA/isolamento & purificação , Receptores Citoplasmáticos e Nucleares/biossíntese , Receptores Citoplasmáticos e Nucleares/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Telemetria , Tiroxina/sangue , Tri-Iodotironina/sangue
9.
Eur J Cancer ; 37(15): 1904-9, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11576847

RESUMO

The aim of this study was to describe and characterise a founder mutation of the BRCA1 gene in western Sweden. Of 62 families screened for BRCA mutations, 24 had BRCA1 mutations and two had BRCA2 mutations. Tumours that occurred in family members were histologically reviewed and mutational status was analysed using archival paraffin-embedded tissues. The same BRCA1 mutation, 3171ins5, was found in 16 families who were clustered along the western coast of Sweden. Mutation analysis revealed a maternal linkage in 13 families and a paternal linkage in 3. There was complete agreement between mutation analysis results obtained from blood and archival tissues. The penetrance of breast or ovarian cancer by age 70 years was estimated to be between 59 and 93%. There were no differences in survivals between breast or ovarian cancer patients with the mutation and age-matched controls. Thus, a predominant BRCA1 gene founder mutation associated with a high risk of breast and ovarian cancer has been identified and found to occur in a restricted geographical area, thereby allowing timely and cost-effective mutation screening using blood samples or archival histological material.


Assuntos
Neoplasias da Mama/genética , Genes BRCA1/genética , Mutação , Síndromes Neoplásicas Hereditárias/genética , Neoplasias Ovarianas/genética , Adulto , Idoso , Neoplasias da Mama/epidemiologia , Análise Mutacional de DNA/métodos , Feminino , Efeito Fundador , Humanos , Incidência , Pessoa de Meia-Idade , Análise Multivariada , Síndromes Neoplásicas Hereditárias/epidemiologia , Neoplasias Ovarianas/epidemiologia , Reação em Cadeia da Polimerase/métodos , Medição de Risco , Taxa de Sobrevida , Suécia/epidemiologia
10.
Am J Surg Pathol ; 22(6): 683-97, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9630175

RESUMO

The clinicopathologic, immunohistochemical, and ultrastructural features of soft tissue angiosarcomas are not well defined. Eighty cases of angiosarcoma that involved the deep subcutis, skeletal muscle, retroperitoneum, mesentery, and mediastinum are reported. The lesions occurred in 50 male and 30 female patients who were 5-97 years of age; the peak incidence was in the seventh decade of life. A variety of associated conditions were documented in 20 of these cases, including a history of other neoplasms (some irradiated), synthetic vessel grafts, heritable conditions, and prior trauma or surgery. The angiosarcomas occurred in the extremities (n = 43 cases), trunk (n = 28), and the head and neck (n = 9) regions, with the thigh and the retroperitoneum being the most common sites. They often were characterized as enlarging, painful masses of several weeks' duration and were occasionally associated with acute hemorrhage, anemia, or a coagulopathy. The tumors measured 1-15 cm in diameter (median 5 cm) and frequently were hemorrhagic and multinodular. There was a wide morphologic spectrum within and between cases, including areas similar to cavernous and capillary hemangioma, Dabska tumor, spindle cell and epithelioid hemangioendothelioma, various spindle cell sarcomas, or carcinoma. Histologically, epithelioid angiosarcoma was the most frequently observed pattern; 70% of cases had epithelioid cells that were arranged in nests, clusters, papillae, and gaping vascular channels. Hemorrhage tended to obscure the diagnosis in several cases and often was associated with papillary endothelial hyperplasia-like areas. All 42 cases studied immunohistochemically stained at least focally for Factor VIII-related antigen, and nearly all stained strongly for vimentin, which accentuated the endothelial cells and vessel lumen formation. CD34 antigen was detected in 74% of cases, BNH9 in 72%, and cytokeratins in 35%. Epithelial membrane antigen, S-100 protein, and HMB45 were not detected. Fifty-five percent of the tumors had intracytoplasmic aggregates of laminin. Immunostains for alpha-smooth muscle actin demonstrated a prominent pericytic component in several tumors (24%). Ki67 immunostains with MIB1 indicated high proliferative activity (> or =10%) in 72% of cases. p53 immunoreactivity (>20% nuclear staining) was observed in 20% of cases. Ultrastructural studies performed on poorly differentiated areas of 12 cases showed groups of cells, which were frequently epithelioid, surrounded by basal lamina, and closely associated with pericytes, along with intercellular and intracellular lumina with or without red blood cells. Whorls of abundant intermediate filaments, occasional tonofilamentlike structures, and pinocytotic vesicles also were noted. In contrast to the findings of others, Weibel-Palade bodies were not seen. Follow-up in 49 cases (61%) showed that 53% of patients were dead of disease at a median interval of 11 months, whereas 31% had no evidence of disease at a median interval of 46 months. The remaining patients were either alive with disease (14%) or alive but disease status was unknown (2%). There were local recurrences in 20% of cases and distant metastases in 49%, most frequently to the lungs, followed by the lymph nodes, soft tissues, bone, liver, and other sites. These results indicate that angiosarcoma of soft tissue is a high-grade sarcoma. Older patient age, tumor location in the retroperitoneum, and larger tumor size as well as detection of MIB1 in > or =10% of the tumor cell population were all associated with a poorer prognosis.


Assuntos
Hemangiossarcoma/patologia , Neoplasias de Tecidos Moles/patologia , Actinas/metabolismo , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/metabolismo , Criança , Pré-Escolar , Feminino , Hemangiossarcoma/metabolismo , Hemangiossarcoma/ultraestrutura , Humanos , Imuno-Histoquímica , Queratinas/metabolismo , Masculino , Microscopia Eletrônica , Pessoa de Meia-Idade , Prognóstico , Neoplasias de Tecidos Moles/metabolismo , Neoplasias de Tecidos Moles/ultraestrutura , Fator de von Willebrand/metabolismo
11.
Am J Surg Pathol ; 22(8): 911-24, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9706971

RESUMO

Acral myxoinflammatory fibroblastic sarcoma is a unique low-grade tumor of modified fibroblasts. It characteristically occurs in the distal extremities and has a propensity to recur locally. Forty-four cases that occurred in 22 males and 22 females from 20 to 91 years of age (median, 53 years) were studied. The lesions, which were 1-6 cm (median, 3 cm), occurred in the hands (64%), the feet (20%), the ankles (11%), and the wrists (5%). The patients usually had a long history of a painless mass (median duration, 1 year). Clinically they were suspected to be ganglion cysts, tenosyonovitis, or giant cell tumors of tendon sheath. Initial histologic diagnoses, in most cases, included pigmented villonodular tenosynovitis or various reactive fibroinflammatory processes. Histologically, the lesions were multinodular, poorly delineated, and characterized by a prominent myxoid matrix containing numerous inflammatory cells, including polymorphonuclear leukocytes, eosinophils, lymphocytes, and plasma cells, as well as fibrosis. Amidst the prominent inflammation, and sometimes obscured by it, were scattered, large, bizarre tumor cells with vesicular nuclei, prominent inclusion-like nucleoli, and abundant eosinophilic cytoplasm, which was homogeneous to vacuolated and often contained intracytoplasmic inflammatory cells. Ultrastructurally, the bizarre tumor cells had features of modified fibroblasts, including an abundance of intermediate filaments and dilated rough endoplasmic reticulum. Immunohistochemically, the neoplastic cells revealed strong positivity for vimentin (25 of 25), focal positivity for CD68 antigen (17 of 25) and CD34 (7 of 25); the tumor cells did not express neuroectodermal, epithelial, or lymphoid markers. The Ki67 labeling index with MIB1 was less than 1% in 20 of 25 cases; p53 immunoreactivity (20-90%) was observed in 7 of 25 primary tumors and in 2 of 3 local recurrences. Follow-up information was available in 36 of 44 cases (median, 5 years). Most excisions were either intralesional or marginal. Ten patients underwent amputation, usually after repeated local recurrences. Radiation therapy and chemotherapy were administered in five and two cases, respectively. Twenty-four cases (67%) had at least one local recurrence. A histologically proven lymph node metastasis developed in one patient, whereas another was stated to have lung metastases, although these were not documented histologically. At last follow-up, 23 patients were alive and well, 11 were alive with disease, and 2 were dead of other causes without evidence of tumor. The prominent inflammation and fibrosis seen histologically in acral myxoinflammatory fibroblastic sarcoma simulate a reactive process. The presence of myxoid foci and scattered bizarre cells, which are occasionally multivacuolated, may cause confusion with malignant fibrous histiocytoma and liposarcoma. Based on the protracted clinical course, a high rate of local recurrence (sometimes necessitating amputation), and a low rate of metastasis, we believe these tumors are low-grade sarcomas. The intimate relationship with the synovium, the frequent association with tenosynovitis, and the prominent inflammatory infiltrate suggest that inflammation may play a role in the pathogenesis of acral myxoinflammatory fibroblastic sarcoma.


Assuntos
Neoplasias Ósseas/metabolismo , Neoplasias Ósseas/patologia , , Mãos , Mixoma/patologia , Osteossarcoma/metabolismo , Osteossarcoma/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Ósseas/cirurgia , Feminino , Humanos , Imuno-Histoquímica , Inflamação/patologia , Masculino , Microscopia Eletrônica , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Osteossarcoma/cirurgia
12.
Am J Surg Pathol ; 18(5): 479-85, 1994 May.
Artigo em Inglês | MEDLINE | ID: mdl-7513502

RESUMO

We present nine cases of an atypical cellular peripheral nerve sheath tumor, designated plexiform malignant peripheral nerve sheath tumor (MPNST) of infancy and childhood, occurring in five boys and four girls aged 50 days to 13 years (median, 1.5 years). The tumors were located in the lower extremities (five cases), upper extremities (three cases), and the orbital region (one case), and they ranged from 1.5 to 8 cm in size (median, 3 cm). Two lesions were congenital, and another was associated with a history of von Recklinghausen's disease. Follow-up, available in six cases, ranged from 6 months to 15 years (median, 51 months); four patients had local recurrences within 8 to 31 months after excision of the initial lesion, and one with an orbital tumor died of locally invasive disease within 6 months. Histologically, the initial lesions were characterized by a predominantly superficial location within the dermis and subcutis, with occasional extension into deeper soft tissues, had infiltrative or sharply demarcated margins, and resembled entangled or intertwined hypercellular nerve trunks, resulting in a plexiform appearance at low magnification. The nuclei were oval to serpentine with a vesicular chromatin pattern and small basophilic nucleoli; mitoses were seen in all cases and averaged from 1 to 18/10 high-power fields (hpf) (median, 4/10 hpf). Neither necrosis nor vascular invasion was seen. Features diagnostic of plexiform or cellular schwannoma, such as nuclear pleomorphism, Antoni B areas, thick-walled hyalinized blood vessels, and secondary degenerative features were lacking. Other than a prominent plexiform architecture, the lesions were indistinguishable from MPNST occurring in other sites in infants and children. Although none metastasized, the histologic similarity of plexiform MPNST to other childhood MPNST, its relatively high propensity for local recurrences, and its potential to behave in a locally aggressive manner indicate that it is best regarded as low-grade malignant. Overall, the behavior of plexiform MPNST is better than other MPNST in children, probably because of its relatively small size, peripheral and superficial location in most instances, absence of necrosis or vascular invasion, occurrence in young patients, and infrequent association with von Recklinghausen's disease rather than a function of its prominent plexiform architecture. Distinction of plexiform MPNST from cellular and plexiform schwannoma, plexiform neurofibroma, and hamartomatous lesions of childhood is important. Complete excision should be ensured to prevent local recurrences and potential metastases.


Assuntos
Neoplasias de Bainha Neural/patologia , Neoplasias do Sistema Nervoso Periférico/patologia , Adolescente , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Lactente , Masculino , Mitose , Invasividade Neoplásica , Recidiva Local de Neoplasia , Neoplasias de Bainha Neural/metabolismo , Neoplasias do Sistema Nervoso Periférico/metabolismo , Coloração e Rotulagem
13.
Am J Surg Pathol ; 22(6): 762-70, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9630185

RESUMO

Benign schwannoma (neurilemoma) has various morphologic patterns that may cause problems in differential diagnosis. Although an epithelioid variant of malignant schwannoma simulating carcinoma and melanoma is well recognized, a benign counterpart has not yet been defined. In the current study, we describe five cases of benign epithelioid schwannoma that were in the subcutis (four cases) and the neck of the urinary bladder (one case). The tumors occurred in adults 28-73 years of age, were 1-4.5 cm in diameter, were well circumscribed and cellular, and were composed of epithelioid cells arranged in cords and nests. The benign nature of the lesions was evident by a constellation of features, including small size, sharp circumscription, bland morphology, low proliferative activity (four of five had < or =1% Ki67 immunostaining), and a benign clinical course after either marginal or intralesional excision. All cases had some features of classic schwannoma light microscopically and a high degree of Schwann cell differentiation both ultrastructurally and immunohistochemically. The recognition of benign epithelioid schwannoma is important because it may be misinterpreted as a malignant neuroectodermal, mesenchymal, epithelioid, or melanocytic tumor.


Assuntos
Neurilemoma/patologia , Neoplasias Cutâneas/patologia , Neoplasias da Bexiga Urinária/patologia , Adulto , Idoso , Biomarcadores Tumorais/metabolismo , Feminino , Humanos , Imuno-Histoquímica , Masculino , Microscopia Eletrônica , Pessoa de Meia-Idade , Neurilemoma/classificação , Neurilemoma/metabolismo , Neurilemoma/ultraestrutura , Proteínas S100/metabolismo , Neoplasias Cutâneas/classificação , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/ultraestrutura , Neoplasias da Bexiga Urinária/classificação , Neoplasias da Bexiga Urinária/metabolismo , Neoplasias da Bexiga Urinária/ultraestrutura , Vimentina/metabolismo
14.
Am J Surg Pathol ; 23(6): 636-50, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10366145

RESUMO

Extraskeletal myxoid chondrosarcoma (EMC), a phenotypically and genotypically distinctive entity, has generally been viewed as a low-grade sarcoma. No studies regarding clinical and morphologic prognostic factors have been performed on a large series of cases with long-term follow-up because of the rarity and protracted clinical course of EMC. The clinical, morphologic, and immunohistochemical features of 117 previously unreported cases were studied and statistically analyzed. The male-to-female ratio was 2:1. The median patient age was 52 years (range, 6-89 years), and the median tumor size was 7 cm (range, 1.1-25 cm). All tumors occurred within the deep subcutis or deeper soft tissues, with 80% occurring in the proximal extremities or limb girdles and 20% in the trunk. Most initial tumor excisions were intralesional or marginal. Follow-up information was available in 99 cases (median, 9 years: range, 2 months-22 years). Forty-eight patients were disease-free, and 41 patients had evidence of disease (18 of these had died of disease). Ten additional patients survived, but their disease status was unknown. There were local recurrences in 40 (48%) of 83 patients, 23 (58%) of whom had multiple local recurrences. Metastases occurred in 35 (46%) of 76 patients. The estimated 5-, 10-, and 15-year survival rates were 90%, 70%, and 60%, respectively. All cases had histologic features characteristic of classical EMC, at least focally. Cellular foci devoid of myxoid matrix and reminiscent of chondroblastoma, Ewing's sarcoma, monophasic and poorly differentiated synovial sarcoma, fibrosarcoma, and rhabdoid tumor were identified in 29% cases. Older patient age, larger tumor size, and tumor location in the proximal extremity or limb girdle were adverse prognostic factors identified by multivariate analysis. Metastasis also adversely affected survival, although local recurrence did not. This study shows that EMC has a unique clinical course, including a high rate of local recurrence, prolonged survival after metastasis in some cases, and eventually a high rate of death due to tumor. These features distinguish EMC from low-grade sarcomas. This study shows that histologic grading is of no prognostic value in EMC because prognosis is dictated primarily by certain clinical features. Histologic recognition of classical EMC and cellular and solid, nonmyxoid variants is important, however, in view of EMC's distinctive biologic behavior.


Assuntos
Condrossarcoma/patologia , Neoplasias de Tecidos Moles/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/análise , Criança , Condrossarcoma/química , Condrossarcoma/mortalidade , Condrossarcoma/secundário , Feminino , Humanos , Técnicas Imunoenzimáticas , Masculino , Microscopia Eletrônica , Pessoa de Meia-Idade , Organelas/ultraestrutura , Prognóstico , Recidiva , Neoplasias de Tecidos Moles/química , Neoplasias de Tecidos Moles/mortalidade , Taxa de Sobrevida
15.
Am J Surg Pathol ; 19(9): 1029-38, 1995 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7661276

RESUMO

Maffucci's syndrome is classically defined as the association of multiple enchondromas and hemangiomas. Spindle-cell hemangioendothelioma (SCH), a recently described vascular tumor of purported low malignant potential, has both cavernous hemangioma and Kaposi-like features. We report six patients with Maffucci's syndrome in whom all vascular lesions were SCH. The enchondromas involved the small and long tubular bones of the extremities in all of these patients; flat bones were also involved in three patients. The SCH usually arose in the extremities, distal to the knees and elbows. Five of the six patients had multiple and separate nodules of SCH, and in four patients there was recurrent or persistent SCH within 6 months to 4 years after initial removal. One patient also had a vascular tumor in the spleen mainly with features of a low-grade angiosarcoma with separate SCH-like foci. None of the SCH have metastasized within a follow-up period averaging 20 years. Five patients are alive 14 to 31 years after presentation. One patient died from metastatic dedifferentiated chondrosarcoma. The patient with the low-grade splenic angiosarcoma is alive approximately 2 years after diagnosis. Reappraisal of the older literature suggests that some of the vascular tumors occurring in Maffucci's syndrome, previously diagnosed as hemangiomas, may in fact be SCH. The apparent association between Maffucci's syndrome and SCH, the presence of SCH in other congenital syndromes, and the young patient age and multicentric distribution of SCH unassociated with Maffucci's syndrome raise the possibility that SCH may be a manifestation of a congenital mesodermal disorder with a genetic background related to Maffucci's syndrome. Although the behavior of SCH appears to be one of a locally recurrent or persistent multicentric lesion that does not metastasize, the association of SCH-like foci in a low-grade angiosarcoma of the spleen raises the possibility that SCH may rarely be associated with a higher grade lesion. Therefore, SCH, at least in the setting of Maffucci's syndrome, should be carefully monitored.


Assuntos
Encondromatose/patologia , Hemangioendotelioma/patologia , Neoplasias de Tecidos Moles/patologia , Adolescente , Criança , Pré-Escolar , Encondromatose/diagnóstico por imagem , Extremidades , Feminino , Seguimentos , Hemangioendotelioma/cirurgia , Humanos , Masculino , Radiografia , Costelas , Neoplasias de Tecidos Moles/cirurgia
16.
Am J Surg Pathol ; 19(9): 979-93, 1995 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7661286

RESUMO

We report 25 cases of a peculiar sclerosing epithelioid variant of fibrosarcoma (SEF) simulating an infiltrating carcinoma. The tumors occurred primarily in the deep musculature and were frequently associated with the adjacent fascia or periosteum. The patients' ages were 14 to 87 years (median, 45). Fourteen were male and 11 female. The tumors were located in the lower extremities and limb girdles (12 cases), trunk (9), upper limb girdles (2), and neck (2). They measured 2 to 14.5 cm in greatest dimension (median size, 7 cm) and were gray to white and firm. Histologically, the lesions were characterized by a proliferation of rather uniform, small, slightly angulated, round to ovoid epithelioid cells with sparse, often clear cytoplasm arranged in distinct nests and cords. In all cases there was prominent hyaline sclerosis, sometimes reminiscent of osteoid or cartilage and foci of conventional fibrosarcoma. Occasional myxoid zones with cyst formation and foci of hyaline cartilage, calcification, and metaplastic bone were also seen. Mitotic figures were generally scarce. Vimentin was detected in 13 of 14 cases, epithelial membrane antigen in seven, S100 protein in four, and neuron-specific enolase in two. Cytokeratins were detected with AE1/AE3 and CAM 5.2 in two cases. Leukocyte common antigen, CD68 antigen, HMB45, desmin, and alpha-smooth muscle actin were negative in all cases. In 13 of 14 cases, 75% or more of the cells stained for proliferating cell nuclear antigen (PCNA). Ki67 immunostaining with MIB 1 showed low proliferative activity in all cases, averaging 5% of tumor cells or less. In all cases, p53 was detected by immunohistochemical methods; bcl-2, an antiapoptosis marker, was detected in more than 90% of the cells in 11 of 12 cases. Ultrastructurally, both the epithelioid and spindled tumor cells had features of fibroblasts. Follow-up in 16 cases ranging from 13 months to 17 years 3 months (median, 11 years 4 months) revealed persistent disease or local recurrences in 53% of patients and metastases in 43%. The metastases were to the lungs (4 cases), skeleton (3), chest wall/pleura (3), pericardium (1), and brain (1). Four patients died of disease, four were alive with disease, two were known to be alive but disease status unknown, and six had no evidence of further disease at last follow-up. The data suggest that SEF is a relatively low-grade fibrosarcoma; yet it is fully malignant despite the presence of histologically benign-appearing foci. The proliferation markers PCNA and Ki67 did not correlate with prognosis.(ABSTRACT TRUNCATED AT 400 WORDS)


Assuntos
Carcinoma/patologia , Fibrossarcoma/patologia , Neoplasias de Tecido Muscular/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Diagnóstico Diferencial , Epitélio/patologia , Feminino , Fibrossarcoma/metabolismo , Fibrossarcoma/mortalidade , Seguimentos , Humanos , Imuno-Histoquímica , Antígeno Ki-67 , Masculino , Microscopia Eletrônica , Pessoa de Meia-Idade , Proteínas de Neoplasias/metabolismo , Neoplasias de Tecido Muscular/metabolismo , Proteínas Nucleares/metabolismo , Antígeno Nuclear de Célula em Proliferação/metabolismo , Esclerose , Análise de Sobrevida
17.
Am J Surg Pathol ; 22(7): 779-94, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9669341

RESUMO

Seventy-three cases of malignant, atypical, and multicentric granular cell tumors of soft tissue were studied to clarify criteria for malignancy and prognostic factors. Six histologic criteria were assessed: necrosis, spindling, vesicular nuclei with large nucleoli, increased mitotic activity (> 2 mitoses/10 high-power fields at 200x magnification), high nuclear to cytoplasmic (N:C) ratio, and pleomorphism. Neoplasms that met three or more of these criteria were classified as histologically malignant; those that met one or two criteria were classified as atypical; and those that displayed only focal pleomorphism but fulfilled none of the other criteria were classified as benign. Hence, 46 cases were classified as histologically malignant, 21 as atypical (3 were multicentric), and 6 as benign (all were multicentric). The patients with benign multicentric and atypical granular cell tumors had no metastases and there were no tumor deaths. In contrast, 11 of 28 patients (39%) with malignant granular cell tumor with follow-up information died of disease at a median interval of 3 years; 8 of 28 (29%) were alive with disease, and 9/28 (32%) were disease free (median intervals, 2 and 7 years, respectively). There were local recurrences in 9 of 28 malignant cases (32%) and metastases in 14 of 28 (50%) (median intervals, each 2 years). Forty-eight cases were studied immunohistochemically; 100% expressed vimentin, 98% S-100 protein, 98% neuron-specific enolase, 69% CD57, and 65% CD68. Alpha-smooth muscle actin, desmin, epithelial membrane antigen (EMA), cytokeratins (with CAM 5.2 and KL-1), chromogranin, and HMB45 were not detected. The proliferative index with Ki67 (MIB 1) was 10-50% in 14 of 25 malignant tumors (56%), and immunostaining for p53 was detected in 50% or more of tumor cells in 17 of 25 (68%); both of these factors were statistically significant with regard to the histologic classification as benign, atypical, or malignant. Ultrastructural examination of 13 benign, atypical, and malignant granular cell tumors showed engorgement of the cytoplasm with complex granules and lysosomes, as well as Schwannian features. By flow cytometric DNA analysis, two of six malignant tumors were aneuploid, two were hyperdiploid, and two were diploid. One atypical tumor was aneuploid and all 11 benign tumors were either diploid (9 cases) or hyperdiploid (2 cases). Statistically significant adverse prognostic factors with regard to survival included local recurrence, metastasis, larger tumor size, older patient age, histologic classification as malignant, presence of necrosis, increased mitotic activity, spindling of tumor cells, vesicular nuclei with large nucleoli, and Ki67 values greater [corrected] than 10%. This study defines clinical and morphologic criteria for malignancy in granular cell tumors and shows that malignant granular cell tumor is a high-grade sarcoma with a high rate of metastases and a short survival.


Assuntos
Biomarcadores Tumorais/metabolismo , Tumor de Células Granulares/diagnóstico , Neoplasias de Tecidos Moles/diagnóstico , Adolescente , Adulto , Idoso , Núcleo Celular/ultraestrutura , Criança , Pré-Escolar , Citoplasma/ultraestrutura , DNA de Neoplasias/análise , Feminino , Seguimentos , Tumor de Células Granulares/genética , Tumor de Células Granulares/metabolismo , Humanos , Técnicas Imunoenzimáticas , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Ploidias , Prognóstico , Estudos Retrospectivos , Neoplasias de Tecidos Moles/genética , Neoplasias de Tecidos Moles/metabolismo , Taxa de Sobrevida
18.
Am J Surg Pathol ; 19(5): 519-30, 1995 May.
Artigo em Inglês | MEDLINE | ID: mdl-7726361

RESUMO

We present 19 cases of a previously undescribed myxoid tumor of the anterior tongue. These lesions occurred in nine women and 10 men aged 9 to 78 years (median, 32 years). Most tumors were seen as slow growing, painless nodules in the anterior dorsal tongue. The duration of growth ranged from a few months to 10 years. All tumors were treated by surgical excision, and two recurred. Microscopically, they exhibited a lobular proliferation of ovoid and fusiform cells, which often had multilobated nuclei and occasional foci of atypia, in a chondromyxoid background. Some tumors entrapped muscle or nerve fibers and had a tendency for blunt infiltration of adjacent tissue. The cells were diffusely and intensely immunoreactive for glial fibrillary acidic protein (GFAP) and cytokeratin but were decorated less frequently with antibodies for smooth muscle actin and S-100 protein. Reactivity for epithelial membrane antigen and desmin was not found. We believe these tumors fail to meet established clinicopathologic criteria for any existing myxoid neoplasms of the tongue, including nerve sheath myxoma, myoepithelioma, benign mixed tumor, ossifying fibromyxoid tumor of soft parts, extraskeletal myxoid chondrosarcoma, and glial and chondroid choristomas or heterotopias. Although the histogenesis of this neoplasm is unclear, we suspect that a cell of undifferentiated ectomesenchyme is the progenitor and suggest the descriptive term ectomesenchymal chondromyxoid tumor (ECT) of the anterior tongue be adopted.


Assuntos
Neoplasias de Tecido Conjuntivo/patologia , Neoplasias da Língua/patologia , Adulto , Idoso , Feminino , Humanos , Imuno-Histoquímica , Masculino , Microscopia Eletrônica , Pessoa de Meia-Idade , Neoplasias de Tecido Conjuntivo/ultraestrutura , Neoplasias da Língua/ultraestrutura
19.
J Endocrinol ; 174(2): R1-6, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12176676

RESUMO

Indian Hedgehog (Ihh) has been reported to control the rate of cartilage differentiation during skeletal morphogenesis in rodents through a negative feedback loop involving parathyroid hormone related protein (PTHrP). The role of Ihh and PTHrP in the regulation of human epiphyseal chondrocytes is unknown. The aim of the current study was to examine the expression and localization of Ihh and PTHrP in the human growth plate at various pubertal stages. Growth plate biopsies were obtained from patients subjected to epiphyseal surgery and the expression of Ihh and PTHrP was detected by immunohistochemistry. We show that Ihh and PTHrP are expressed mainly in early hypertrophic chondrocytes in the human growth plate. The levels of expression of Ihh and PTHrP are higher in early stages of puberty than later. Our results suggest that Ihh and PTHrP are present in the human growth plate and that Ihh and PTHrP may be involved in the regulation of pubertal growth in humans.


Assuntos
Lâmina de Crescimento/química , Proteínas/análise , Puberdade/metabolismo , Transativadores/análise , Adolescente , Criança , Feminino , Proteínas Hedgehog , Humanos , Processamento de Imagem Assistida por Computador , Imuno-Histoquímica/métodos , Masculino , Proteína Relacionada ao Hormônio Paratireóideo
20.
J Endocrinol ; 171(1): 15-22, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11572786

RESUMO

Thyroid hormone receptor alpha 1, beta 1 and beta 2-deficient mice (TR alpha 1-/-beta-/- mice) demonstrate growth retardation and defective ossification in the epiphyses associated with an inhibition of the GH/IGF-I axis. There are differences between TR alpha 1-/-beta-/- mice (receptor deficient) and the hypothyroid animal model (ligand deficient). Such differences include possible repressive actions exerted by unliganded receptors in the ligand-deficient (hypothyroid) model but not in the receptor-deficient model. In the present study we have investigated whether or not GH substitution rescues the skeletal phenotype of TR alpha 1-/-beta-/- mice. TR alpha 1-/-beta-/- and wild-type (WT) mice were treated with GH from day 18 until 10 weeks of age. GH substitution of mutant mice resulted in a significant and sustained stimulatory effect on the body weight that was not seen in WT mice. GH-treated mutant mice but not GH-treated WT mice demonstrated increased length and periosteal circumference of the femur. However, GH substitution did not reverse the defective ossification seen in TR alpha 1-/-beta-/- mice. TR alpha 1-/-beta-/- mice displayed increased width of the proximal tibial growth plate, which was caused by increased width of the proliferative but not the hypertrophic layer. GH substitution did not restore the disturbed morphology of the growth plate in TR alpha 1-/-beta-/- mice. In summary, GH substitution reverses the growth phenotype but not the defective ossification in TR alpha 1-/-beta-/- mice. Our data suggest that TRs are of importance both for the regulation of the GH/IGF-I axis and for direct effects on cartilage.


Assuntos
Transtornos do Crescimento/tratamento farmacológico , Transtornos do Crescimento/genética , Hormônio do Crescimento/uso terapêutico , Lâmina de Crescimento/fisiopatologia , Receptores dos Hormônios Tireóideos/genética , Absorciometria de Fóton , Animais , Composição Corporal , Fêmur/fisiopatologia , Deleção de Genes , Transtornos do Crescimento/fisiopatologia , Fator de Crescimento Insulin-Like I/análise , Camundongos , Camundongos Mutantes , Tíbia/fisiopatologia , Tomografia Computadorizada por Raios X
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