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1.
Osteoporos Int ; 23(3): 1171-6, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21305266

RESUMO

UNLABELLED: Sclerostin is expressed by osteocytes and inhibits bone formation by osteoblasts. In this study, serum sclerostin was positively correlated with either lumbar spinal bone mineral density or T-score. Furthermore, serum sclerostin was increased after 6 months treatment with risedronate, whereas remained unchanged after 6 months teriparatide treatment. INTRODUCTION: The primary aim of this study was the evaluation of serum sclerostin levels in postmenopausal women and their association with bone mineral density (BMD) and bone turnover markers. The secondary aim was the evaluation of treatment with either teriparatide (TPTD) or risedronate (RIS) on serum sclerostin levels in women with postmenopausal osteoporosis. METHODS: Women with postmenopausal osteoporosis, assigned to receive either TPTD (TPTD group, n = 13) or RIS (RIS group, n = 36) for 6 months, and non-osteoporotic early postmenopausal women (NOEP group, n = 13) were recruited. Main outcome measure was serum sclerostin levels. RESULTS: Serum sclerostin was higher in the NOEP group at baseline compared with either TPTD group (p = 0.007) or RIS group (p = 0.049). Sclerostin was positively correlated with both lumbar spinal (LS) BMD (r = 0.353; p = 0.005) and T-score (r = 0.501; p < 0.001) and negatively correlated with intact parathyroid hormone (r = -0.343; p = 0.024) at baseline. Multiple regression analysis showed that either LS BMD (Beta = 0.653; p = 0.018) or T-score (Beta = 0.711; p = 0.005) were independent predictors of serum sclerostin levels. No significant correlation was observed between serum sclerostin and bone turnover markers or estradiol at baseline. Sclerostin was significantly increased 6 months post-treatment in RIS group (p = 0.002), whereas remained statistically unaffected in the TPTD group. CONCLUSIONS: Serum sclerostin is decreased in women with postmenopausal osteoporosis compared with non-osteoporotic early postmenopausal women and is positively correlated to either LS BMD or LS T-score. Furthermore, serum sclerostin was increased after 6 months treatment with RIS, whereas remained essentially unchanged after 6 months TPTD treatment.


Assuntos
Conservadores da Densidade Óssea/farmacologia , Densidade Óssea/fisiologia , Proteínas Morfogenéticas Ósseas/sangue , Vértebras Lombares/fisiopatologia , Osteoporose Pós-Menopausa/sangue , Proteínas Adaptadoras de Transdução de Sinal , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Densidade Óssea/efeitos dos fármacos , Conservadores da Densidade Óssea/uso terapêutico , Proteínas Morfogenéticas Ósseas/efeitos dos fármacos , Remodelação Óssea/efeitos dos fármacos , Remodelação Óssea/fisiologia , Ácido Etidrônico/análogos & derivados , Ácido Etidrônico/farmacologia , Ácido Etidrônico/uso terapêutico , Feminino , Marcadores Genéticos/efeitos dos fármacos , Humanos , Vértebras Lombares/efeitos dos fármacos , Pessoa de Meia-Idade , Osteoporose Pós-Menopausa/tratamento farmacológico , Pós-Menopausa/sangue , Estudos Retrospectivos , Ácido Risedrônico , Teriparatida/farmacologia , Teriparatida/uso terapêutico
2.
J Endocrinol Invest ; 35(9): 866-8, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22842667

RESUMO

OBJECTIVE: This study was carried out in order to evaluate the effect of 18-month treatment with PTH (1-34) or PTH (1-84) on serum sclerostin levels in humans. SUBJECTS AND METHODS: We investigated 10 women with severe osteoporosis, previously treated with alendronate and 20 untreated osteoporotic women. Subjects with severe osteoporosis were randomly divided into 2 groups of 5 patients each; the first group was treated with 20 µg of PTH (1-34) and the second one with 100 µg of PTH (1-84) according to an open-label design. Fasting blood samples were collected at baseline and at 2, 4, and 24 h after hormone administration. The same protocol was followed at month 1, 6, 12, 18. Serum sclerostin levels were measured at each time point by a sandwich-type enzyme-linked immunosorbent assay. RESULTS: Basal serum sclerostin levels were not significantly different between patients previously treated with alendronate and those never treated. No significant acute change of serum sclerostin levels was observed after PTH administration. Fitting a mixed effect regression model, we found a significant time effect (p=0.0012) using the sclerostin level as the response variable and the month of drug administration as a single covariate. Treatment with both PTH molecules induced a monthly mean reduction of sclerostin levels of 0.1956 pmol/l. CONCLUSIONS: Our results indicate that long-term therapy with PTH (1-34) or PTH (1-84) in women with osteoporosis previously treated with alendronate is associated with a reduction in circulating sclerostin levels. This is a putative mechanism through which PTH performs its anabolic action.


Assuntos
Alendronato/uso terapêutico , Conservadores da Densidade Óssea/uso terapêutico , Densidade Óssea/efeitos dos fármacos , Proteínas Morfogenéticas Ósseas/sangue , Osteoporose Pós-Menopausa/sangue , Hormônio Paratireóideo/sangue , Pós-Menopausa , Proteínas Adaptadoras de Transdução de Sinal , Idoso , Estudos de Casos e Controles , Feminino , Marcadores Genéticos , Humanos , Osteoporose Pós-Menopausa/diagnóstico , Osteoporose Pós-Menopausa/tratamento farmacológico , Prognóstico
3.
Exp Clin Endocrinol Diabetes ; 116(8): 491-5, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18072013

RESUMO

BACKGROUND: Osteoporosis is one of the most common conditions associated with aging. It is based on an excess of bone resorption over bone formation, leading to an imbalance of bone turnover. The receptor activator of nuclear factor kappaB ligand (RANKL) is an important regulator of bone metabolism. OBJECTIVE: The aim of this investigation was to evaluate potential age- and gender-related changes in free RANKL and total RANKL (free RANKL+RANKL/osteoprotegerin complexes). METHODS: Two hundred and forty volunteers with a median age of 48 years were included in the study. Serum levels of free RANKL and total RANKL were evaluated. RESULTS: On average, men have a 1.77-fold higher free RANKL level and a 2.12-fold higher free/total RANKL ratio than women of the same age. On average, the RANKL levels decrease by approximately 13% every five years. CONCLUSION: This study showed that serum levels of free RANKL and total RANKL decrease with age, and also revealed some gender-related differences.


Assuntos
Ligante RANK/sangue , Adulto , Idoso , Envelhecimento , Índice de Massa Corporal , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Osteoprotegerina/sangue , Seleção de Pacientes , Valores de Referência , Caracteres Sexuais
4.
J Am Coll Cardiol ; 32(6): 1695-700, 1998 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-9822098

RESUMO

OBJECTIVES: We tested the hypothesis that, in patients with stable heart failure, measuring big endothelin-1 (ET-1) plasma level at rest predicts short-term prognosis better than peak oxygen consumption (VO2max) at exercise. BACKGROUND: Cardiopulmonary exercise testing and evaluation of neurohumoral plasma factors are established tools to estimate survival in patients with heart failure. No data, however, exist comparing the prognostic value of both marker categories simultaneously. METHODS: Two hundred twenty-six heart failure patients were studied in regard to a combined end point of death and prioritization for urgent cardiac transplantation within 1 year follow-up. RESULTS: During the study period 149 patients were without cardiac events (group A), 69 patients died or were urgently transplanted (group B) and 8 patients were alive after a nonurgent heart transplant operation. Norepinephrine (p < 0.0001), atrial natriuretic peptide (p < 0.001), big endothelin plasma levels (p < 0.0001 as well as workload, VO2max and achieved percentage of predicted peak oxygen consumption (pVO2max) (all p < 0.0001) differed significantly between groups A and B. In multivariate stepwise regression analysis, however, only big ET-1 plasma concentration (chi2=74.4, p < 0.0001), New York Heart Association function class (chi2=33.9, p < 0.0001), maximal workload (chi2=7.2, p < 0.01, and plasma atrial natriuretic peptide (ANP) concentration (chi2=4.6, p < 0.05) were independently related to outcome. Peak oxygen consumption or pVO2max did not reach statistical significance in this model. Event-free survival rates were significantly lower in patients with a big ET-1 level of 4.3 fmol/ml or more than with lower big ET-1 levels (p < 0.0001). CONCLUSION: We conclude that in patients with chronic heart failure who are stable on oral therapy measuring big ET-1 and ANP plasma levels may be a valuable noninvasive adjunct to improve the prognostic accuracy of detecting high risk patients compared with exercise testing alone.


Assuntos
Baixo Débito Cardíaco/fisiopatologia , Endotelinas/sangue , Teste de Esforço/normas , Coração/fisiopatologia , Pulmão/fisiopatologia , Precursores de Proteínas/sangue , Adulto , Idoso , Baixo Débito Cardíaco/sangue , Baixo Débito Cardíaco/tratamento farmacológico , Endotelina-1 , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Prognóstico , Modelos de Riscos Proporcionais , Medição de Risco , Análise de Sobrevida , Fatores de Tempo
5.
Exp Gerontol ; 40(6): 532-5, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15935595

RESUMO

Bone turnover increases with age. In a previous study, we reported on bone metabolism in young and elderly women and men. The aim of the present investigation was to evaluate potential age- and gender-related changes in cathepsin K, a cysteine protease that plays an important role in the degradation of the organic matrix of bone. Twenty-five healthy premenopausal women, 24 young healthy men, 26 elderly women, and 25 elderly men participated in the study. Elderly women and men had significantly lower cathepsin K levels than younger ones. In both men and women, serum levels of cathepsin K were negatively correlated with age. In men there was a statistically significant negative correlation between serum levels of cathepsin K and osteoprotegerin, which inhibits osteoclast differentiation and activation. No association was found between serum levels of cathepsin K and bone-specific alkaline phosphatase, osteocalcin, or 25-hydroxy vitamin D. Thus, the age-related increase in OPG, which markedly inhibits the expression of cathepsin K, may also reduce serum levels of cathepsin K. Despite the age-related increase in bone resorption, this study shows lower cathepsin K values in elderly women and men than in younger subjects. It might be speculated that a different enzyme could compensate for the decline in cathepsin K during old age.


Assuntos
Envelhecimento/sangue , Catepsinas/sangue , Adulto , Idoso de 80 Anos ou mais , Fosfatase Alcalina/sangue , Reabsorção Óssea/metabolismo , Osso e Ossos/metabolismo , Catepsina K , Cisteína Endopeptidases/sangue , Feminino , Glicoproteínas/sangue , Humanos , Masculino , Osteocalcina/sangue , Osteoprotegerina , Receptores Citoplasmáticos e Nucleares/sangue , Receptores do Fator de Necrose Tumoral/sangue , Fatores Sexuais , Vitamina D/análogos & derivados , Vitamina D/sangue
6.
J Bone Miner Res ; 8(4): 459-65, 1993 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8475795

RESUMO

To assess the effect of chronically elevated plasma growth hormone (GH) levels on bone metabolism and bone mineral density (BMD), 16 patients (10 females and 6 males) with a mean age of 49.1 +/- 13.2 years (range 33-68) with active acromegaly were studied and compared to a control group of 16 sex- and age-matched subjects. BMD of the lumbar spine and two different sites of the proximal femur were measured by dual-energy x-ray absorptiometry (Norland XR-26). In the acromegalic patients the mean plasma GH concentration was 30.1 +/- 11.1 micrograms/liter, and the mean plasma somatomedin C (SMC) concentration was 6.5 +/- 1.5 U/liter. Mean serum osteocalcin (OC) levels (14.3 +/- 1.1 versus 7.2 +/- 0.4 ng/ml, p < 0.001) as well as the urinary hydroxyproline excretion (OHP; 8.8 +/- 1.4 versus 2.7 +/- 0.3 mg, p < 0.0001) were significantly higher in the acromegalic patients than in the control subjects. In the acromegalic patients BMD was significantly elevated in the two examined regions of the proximal femur, that is, the femoral neck (1.06 +/- 0.05 versus 0.86 +/- 0.03 g/cm2, p < 0.05) and Ward's triangle (0.92 +/- 0.06 versus 0.76 +/- 0.03 g/cm2, p < 0.02), whereas the BMD of the lumbar spine was not significantly different from that of control subjects. Among the patients with acromegaly a significant positive correlation between serum OC concentrations, on the one hand, and urinary OHP excretion (r = 0.7, p < 0.004) as well as BMD in the proximal femur (r = 0.64, p < 0.007), on the other hand, could be observed.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Acromegalia/fisiopatologia , Densidade Óssea/fisiologia , Absorciometria de Fóton , Acromegalia/metabolismo , Adulto , Idoso , Feminino , Colo do Fêmur/metabolismo , Hormônio do Crescimento/sangue , Hormônio do Crescimento/fisiologia , Humanos , Hidroxiprolina/urina , Fator de Crescimento Insulin-Like I/metabolismo , Vértebras Lombares/metabolismo , Masculino , Pessoa de Meia-Idade , Osteocalcina/sangue
7.
J Clin Endocrinol Metab ; 66(5): 1071-4, 1988 May.
Artigo em Inglês | MEDLINE | ID: mdl-3258869

RESUMO

Osteocalcin (OC) is a noncollagenous bone matrix protein containing gamma-carboxyglutamic acid, the synthesis of which is vitamin K dependent. Serum OC levels are generally believed to reflect the de novo synthesis of OC by osteoblasts and thus reflect bone formation. We measured serum OC levels by RIA in 48 patients receiving phenprocoumon anticoagulant treatment, which inhibits the posttranscriptional synthesis of gamma-carboxyglutamic acid, and in 22 matched normal subjects. The median serum OC level in the patients receiving phenprocoumon therapy was significantly lower than that in the normal subjects (P less than 0.0001). In 27 patients receiving anticoagulant therapy and in 21 normal subjects the proportion of noncarboxylated OC to total OC also was determined. The proportion of OC that was noncarboxylated was significantly higher in the patients receiving phenprocoumon therapy than in the normal subjects (P less than 0.0001). We conclude that OC carboxylation is impaired in patients receiving oral anticoagulant therapy. The decreased total OC levels in patients receiving phenprocoumon treatment might result from decreased bone formation, although these patients do not have symptoms of bone disease.


Assuntos
4-Hidroxicumarinas/uso terapêutico , Proteínas de Ligação ao Cálcio/sangue , Femprocumona/uso terapêutico , Idoso , Reabsorção Óssea , Osso e Ossos/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Osteocalcina
8.
Bone ; 32(6): 681-6, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12810175

RESUMO

Regulation of the balance of osteoblastic and osteoclastic activity is critical for the understanding of normal cell biology and forms the basis of metabolic bone diseases. Our study reports about influences of age and gender on serum levels of osteoprotegerin (OPG) and its association to other clinical parameters of bone metabolism in a precisely determined cohort of 1134 healthy subjects at 17 Austrian outpatient bone clinics, aged between 19 and 96 years (females n = 687, 50 +/- 21 years, 19-94, and males n = 447, 52 +/- 13.5 years, 24-96). Mean OPG serum levels for all participants were 50.83 +/- 51.47 pg/ml (n = 1134; median 36, 2-584) and we observed a sharp increase in females after 60 years and in males after 70 years of age. OPG serum levels increased significantly by age, 2.1 pg/ml in females and 1.9 pg/ml in males for every year (P < 0.0001). Correlation of OPG serum levels and several bone parameters of bone metabolism showed that OPG negatively correlated with serum iPTH (r = -0.14; P < 0.001) and with serum estradiol in females (r = -0.16, P < 0.0001). Bone mineral density measured by DXA method at the spine and at the hip did not correlate with OPG serum levels, except a borderline negative correlation at the trochanteric region (r = -0.1, P < 0.05) in females only. Our results show a significant increase of osteoprotegerin with age in healthy females and males but fluctuations do not predict bone mineral density under in vivo conditions.


Assuntos
Envelhecimento/sangue , Glicoproteínas/sangue , Vigilância da População/métodos , Receptores Citoplasmáticos e Nucleares/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Osteoprotegerina , Receptores do Fator de Necrose Tumoral , Análise de Regressão , Caracteres Sexuais , Estatísticas não Paramétricas
9.
J Immunol Methods ; 90(1): 1-6, 1986 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-3754882

RESUMO

Synthetic calcitonin (CT) and Tyr(0)-katacalcin (tKT) were radioiodinated with Iodogen to high specific activity and with high yields. The products of the iodination procedure were chromatographed on Sephadex G-25 to remove unreacted iodide and then separated by chromatofocussing on PBE 94 (pH 9.6-6.0 for CT and pH 7.4-4.0 for tKT). Clear separation between uniodinated peptides and their mono- and di-iodinated derivatives was achieved with specific activities of 1900 and 3800 Ci/mmol for the respective mono- and di-iodinated peptides. Yields were up to 36 and 24% of mono- and di-iodinated CT and 41 and 29% for mono- and di-iodinated tKT. Our results show that Iodogen provides an effective and gentle way to iodinate peptides with high efficiency. Chromatofocussing is a simple, inexpensive and instrumentally undemanding method that can be performed without specialized chromatographic equipment and that should be applicable to a variety of different tracer preparations.


Assuntos
Calcitonina/metabolismo , Iodo/síntese química , Iodóforos/síntese química , Compostos de Tosil , Ureia/análogos & derivados , Calcitonina/síntese química , Cloraminas , Cromatografia em Gel , Lactoperoxidase , Fragmentos de Peptídeos/metabolismo , Peptídeos/isolamento & purificação , Ureia/metabolismo
10.
Am J Med ; 95(2): 197-202, 1993 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8356983

RESUMO

PURPOSE: This prospective study was designed to assess the effect of primary hyperparathyroidism on heart muscle, valves, and myocardial function. Echocardiography was used to evaluate changes in mechanical performance, the thickness of the left ventricular wall, myocardial calcific deposits, and valvular calcifications in patients with primary hyperparathyroidism. METHODS: Echocardiography was performed in 54 patients with hyperparathyroidism prior to surgery and 12 +/- 2 months after successful parathyroidectomy. A matched control group was followed for comparison. RESULTS: In a blinded fashion, aortic and mitral valve calcifications were detected in 63% and 49% of patients with primary hyperparathyroidism (controls: 12% and 15%, respectively). Calcific deposits in the myocardium were found in 69% of patients with hyperparathyroidism and 17% of the control subjects. After parathyroidectomy and 12 months of normocalcemia, a significant regression of left ventricular hypertrophy (p < 0.001) was observed. CONCLUSIONS: The present data show a high incidence of left ventricular hypertrophy, calcific deposits in the myocardium, and/or aortic and mitral valve calcification in patients with primary hyperparathyroidism. A 1-year follow-up after parathyroidectomy (and restoration of normocalcemia) discloses regression of hypertrophy, while calcifications persist without evidence of progression.


Assuntos
Calcinose/etiologia , Cardiomiopatias/etiologia , Hiperparatireoidismo/complicações , Hiperparatireoidismo/cirurgia , Hipertrofia Ventricular Esquerda/etiologia , Paratireoidectomia , Adulto , Idoso , Calcinose/diagnóstico por imagem , Calcinose/epidemiologia , Cardiomiopatias/diagnóstico por imagem , Cardiomiopatias/epidemiologia , Ecocardiografia , Feminino , Seguimentos , Humanos , Hipertrofia Ventricular Esquerda/diagnóstico por imagem , Hipertrofia Ventricular Esquerda/epidemiologia , Incidência , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Indução de Remissão , Resultado do Tratamento
11.
Am J Med ; 85(6): 780-4, 1988 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-3195602

RESUMO

PURPOSE AND METHODS: A number of endocrine peptides and proteins are expressed by medullary thyroid carcinoma (MTC). The expression of two newly appreciated neuroendocrine tumor markers, chromogranin A (CgA) and the endocrine antigen defined by monoclonal antibody HISL-19, was determined in 14 MTCs by immunohistology to evaluate the clinical utility of these markers in the diagnosis of MTC. Papillary, follicular, and undifferentiated thyroid tumors were also evaluated along with an MTC cell line. The same tissues were evaluated with antibodies to human calcitonin. RESULTS: All human calcitonin antibodies were found to react with the MTCs. In addition, all MTCs were reactive for CgA and the antigen detected by antibody HISL-19. CgA was generally present in the human calcitonin-containing cells, whereas the HISL-19 antigen had a more distinctive distribution. The other thyroid tumors failed to show reactivity with any of the three antibodies. CONCLUSION: Our results demonstrate that, in addition to human calcitonin, MTCs commonly express CgA and the antigen defined by antibody HISL-19. Our observations thus add to the repertoire of endocrine substances produced by MTC. These studies also demonstrate the clinical value of immunohistologic procedures for two novel antigens in distinguishing MTCs from other thyroid tumors.


Assuntos
Biomarcadores Tumorais/análise , Carcinoma/análise , Cromograninas/análise , Proteínas de Neoplasias/análise , Proteínas do Tecido Nervoso/análise , Neoplasias da Glândula Tireoide/análise , Adenocarcinoma/análise , Anticorpos Monoclonais , Calcitonina/análise , Carcinoma/diagnóstico , Carcinoma Papilar/análise , Cromogranina A , Humanos , Imuno-Histoquímica , Neoplasias da Glândula Tireoide/diagnóstico
12.
Transplantation ; 72(1): 89-94, 2001 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-11468540

RESUMO

BACKGROUND: Successful kidney transplantation normalizes elevated proatrial natriuretic peptide (proANP) plasma concentrations of renal failure patients in the early posttransplant period. We evaluated plasma and urinary proANP fragments in the late posttransplant period. METHODS: Immunoreactive proANP(1-30) and proANP(31-67) were determined in 389 renal transplant (Rtx) recipients in the long-term, follow-up period and in 16 healthy controls. RESULTS: Rtx recipients had significantly higher concentrations of proANP(1-30) and proANP(31-67) in both plasma and urine than healthy controls. Although their graft function was normal, all of these long-term Rtx recipients were taking glucocorticoids, which increase proANP(1-30) and proANP(31-67) in the circulation to the extent found in this investigation. Two-thirds of these recipients were also taking cyclosporine, which also increases atrial peptides. Urinary proANP(31-67) was significantly higher than urinary proANP(1-30); 5.5-fold in Rtx patients and 2-fold in controls. Deterioration of renal graft function was associated with a rise of plasma proANP(1-30) from 0.98+/-0.66 to 6.28+/-3.55 nmol/l (P<0.0001) and plasma proANP(31-67) from 1.81+/-1.04 to 7.89+/-3.76 nmol/l (P<0.0001). Urinary excretion of proANP(1-30) increased from 0.27+/-0.34 to 5.96+/-5.07 nmol/24 hr (P<0.0001) and proANP(31-67) from 1.45+/-0.85 to 12.23+/-5.12 nmol/24 hr (P<0.0001). Also proteinuria enhanced plasma and urinary proANP fragments. CONCLUSIONS: ProANP(1-30) and proANP(31-67) of Rtx recipients are affected by immunosuppression, hypertension, renal failure, and proteinuria. One would have expected proANP(1-30) and proANP(31-67) not to normalize because of the glucocorticoids that they were receiving.


Assuntos
Fator Natriurético Atrial/sangue , Fator Natriurético Atrial/urina , Transplante de Rim , Fragmentos de Peptídeos/sangue , Fragmentos de Peptídeos/urina , Precursores de Proteínas/sangue , Precursores de Proteínas/urina , Adulto , Idoso , Creatinina/sangue , Feminino , Humanos , Rim/fisiopatologia , Nefropatias/sangue , Nefropatias/urina , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório , Proteinúria/sangue , Proteinúria/urina , Valores de Referência
13.
Transplantation ; 41(6): 716-9, 1986 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-3087039

RESUMO

We have recently shown that interferon-gamma is capable of activating the key enzyme of pterin biosynthesis in macrophages. This leads to excretion of the stable degradation product neopterin. In this article we present experimental evidence suggesting that stimulation of T cells by alloantigens is associated with release of interferon-gamma--which, in the case of rejection, is locally restricted and not always detectable in the bloodstream. Neopterin induced by this lymphokine, however, readily penetrates tissue barriers and is detectable in the serum. This conclusion is based on two different sets of observations: (1) If supernatants of MLCs are compared with sera from patients with documented acute rejection episodes for their interferon-gamma and neopterin levels, a marked gradient is observed to exist between interferon levels measured in vitro and in vivo; this is not the case for neopterin for which comparable levels were seen. (2) Detection of interferon-gamma in sera of allograft recipients invariably precedes an increase of neopterin; on the other hand, increasing neopterin counts are also seen in the absence of detectable interferon-gamma levels in the serum. It thus appears that although interferon-gamma release during allograft rejection is primarily restricted to the tissue, evaluation of certain metabolites of interferon-dependent metabolic pathways enables definition of its endogenous release. Whereas interferon gamma represents a less reliable marker in the monitoring of rejection episodes, it might offer an additional means to differentiate rejection from systemic infections. Such a discrimination can not be achieved with the neopterin marker.


Assuntos
Biopterinas/sangue , Interferon gama/sangue , Isoantígenos/imunologia , Ativação Linfocitária , Pteridinas/sangue , Doença Aguda , Biopterinas/análogos & derivados , Rejeição de Enxerto , Humanos , Infecções/sangue , Infecções/etiologia , Transplante de Rim , Neopterina , Fito-Hemaglutininas/farmacologia
14.
Transplantation ; 50(4): 620-5, 1990 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-2171163

RESUMO

Serum levels of interferon-gamma and the IFN-dependent marker molecules neopterin and beta 2-microglobulin were assessed in BMT recipients. Concentrations of the latter two markers were corrected for creatinine levels in order to eliminate the impact of alteration of kidney function. Serum levels were assessed daily using commercially available radioimmunoassays. Twelve patients were studied during the early phase of allogeneic bone marrow transplantation and eleven additional patients during complications of BMT. Results indicated that both the conditioning regimen for BMT as well as major clinical complications such as infection and acute graft-versus-host disease strongly influence the endogenous patterns of the lymphokine and its secondary messages. During allogeneic BMT IFN-gamma and neopterin levels exhibited a biphasic pattern with a first peak during conditioning with high-dose cyclophosphamide and a second still higher peak at the time of hemopoietic regeneration. beta-2-microglobulin ratios increased during conditioning and remained elevated throughout observation. Serious infections of bacterial and viral origin as well as GvHD were accompanied by elevated levels of all three serum parameters studied. The kinetics of enhanced endogenous production, however, differed between infectious complications and GvHD. Increasing concentrations were observed during infections subsequent to clinical manifestation, whereas they preceded disease manifestation in GvHD.


Assuntos
Biopterinas/análogos & derivados , Transplante de Medula Óssea , Interferon gama/sangue , Sistemas do Segundo Mensageiro , Microglobulina beta-2/análise , Biopterinas/sangue , Transplante de Medula Óssea/efeitos adversos , Infecções por Citomegalovirus/sangue , Doença Enxerto-Hospedeiro/sangue , Doença Enxerto-Hospedeiro/etiologia , Antígenos de Histocompatibilidade Classe I/imunologia , Humanos , Neopterina , Pneumonia/sangue , Transplante Homólogo
15.
J Nucl Med ; 34(7): 1039-44, 1993 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8315476

RESUMO

Because of their high affinity for bone, bisphosphonates are used both in the treatment of benign and malignant bone disease and in radiopharmaceutical bone imaging. A prospective study was undertaken to evaluate whether intravenous clodronate (dichloromethylene bisphosphonate) therapy might affect the results of bone scintigraphy with 99mTc-labeled methylene diphosphonate (MDP). In 11 female patients with breast cancer and metastatic bone disease, quantitative bone scans were obtained using a region of interest (ROI) method on Days 0 and 22. After intravenous clodronate therapy from Day 1 to Day 21, all metastatic bone lesions were still detectable, and median ROI ratios did not differ to a statistically significant extent from baseline values. Serum calcium levels decreased (p = 0.0449), whereas parathyroid hormone concentrations showed an increase (p = 0.0053). Mean serum levels of creatinine, inorganic phosphorus, osteocalcin, gamma glutaminyl-transpeptidase and alkaline phosphatase remained unchanged. However, a more than twofold rise in the serum activity of alkaline phosphatase was measured in three patients. We conclude that 3 wk of intravenous clodronate treatment did not impair the sensitivity of 99mTc-MDP bone scintigraphy in detecting bone lesions in patients with metastatic breast cancer.


Assuntos
Neoplasias Ósseas/diagnóstico por imagem , Neoplasias Ósseas/secundário , Osso e Ossos/diagnóstico por imagem , Neoplasias da Mama/patologia , Ácido Clodrônico/uso terapêutico , Neoplasias Ósseas/tratamento farmacológico , Reações Falso-Negativas , Feminino , Humanos , Pessoa de Meia-Idade , Estudos Prospectivos , Cintilografia , Sensibilidade e Especificidade , Medronato de Tecnécio Tc 99m , Fatores de Tempo
16.
Semin Nephrol ; 21(3): 298-302, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11320498

RESUMO

Patients with end-stage renal disease have a deranged sodium and water homeostasis leading to chronic volume overload. Atrial natriuretic peptides (ANPs) are circulating hormones that are involved in the regulation of volume homeostasis, blood pressure control, and electrolyte balance. In hemodialysis patients plasma ANPs are highly elevated and decrease during the dialysis session when fluid is removed. However, hemodialysis treatment never corrects the defect in the metabolism of these peptides and their circulating concentrations do not return to levels found in healthy controls. Besides uremia and chronic volume overload, other factors such as cardiac dysfunction or hypertension may contribute to the elevated plasma concentrations of ANPs. ProANP fragments which derive from the N-terminus of the ANP prohormone have been also found in the circulation and they have biological functions similar to alpha-ANP (ie, the C-terminus of the prohormone). The proANP peptides proANP(1-30), proANP(31-67), and proANP(1-98) are increased in patients undergoing regular hemodialysis treatment, but their decrease during the dialysis procedure is less pronounced than for alpha-ANP or cyclic GMP. Cellulose triacetate dialyzer membrane material lowered the plasma concentrations of proANP(1-30), proANP(31-67), and proANP(1-98) significantly more than polysulfone, whereas alpha-ANP and cyclic GMP were not differently affected. Aside from a variety of factors that influence circulating natriuretic factors in the uremic patient, there is evidence for differences in dialyzer membrane adsorption of these peptides which speculatively may be linked to dialysis-associated symptoms.


Assuntos
Fator Natriurético Atrial/sangue , Fator Natriurético Atrial/farmacocinética , Uremia/sangue , Adsorção , Humanos , Rim/metabolismo , Falência Renal Crônica/sangue , Falência Renal Crônica/terapia , Volume Plasmático/fisiologia , Diálise Renal/efeitos adversos , Uremia/etiologia
17.
Chest ; 93(1): 31-7, 1988 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-2961514

RESUMO

Human atrial natriuretic peptide (hANP) is stored by granules of both human atria. Atrial distension appears to be a major stimulus for hANP secretion. Precapillary pulmonary hypertension increases right ventricular afterload and may thus cause right atrial distension. We therefore hypothesized that hANP plasma concentrations (1) are higher in the right atrium than in the peripheral vein, (2) are increased in patients with precapillary pulmonary hypertension, and (3) correlate with right atrial pressure. Thirty-three adult patients with chronic obstructive pulmonary disease (COPD) or interstitial fibrosis were examined by right heart catheterization. Mean pressures were measured in the right atrium, pulmonary artery, and pulmonary capillary wedge position, and blood was drawn from the right atrium and from a peripheral vein for determination of hANP levels. In general, hANP plasma levels in the right atrium were significantly higher than in a peripheral vein. Seventeen out of 33 patients had pulmonary hypertension, whereas 16 patients exhibited normal pulmonary artery mean pressures. In all patients, pulmonary arterial wedge pressure was normal. Plasma hANP concentrations were significantly higher in patients with pulmonary hypertension than in patients with normal pulmonary artery pressure. A strong correlation between central or peripheral hANP plasma levels (or both) and mean right atrial pressure could be observed (r = 0.75; p less than 0.001). From these data, we conclude that the increased secretion of hANP in our patients with precapillary pulmonary hypertension appears to be mediated by right atrial distension.


Assuntos
Fator Natriurético Atrial/sangue , Hipertensão Pulmonar/sangue , Pneumopatias Obstrutivas/sangue , Fibrose Pulmonar/sangue , Adulto , Idoso , Pressão Sanguínea , Débito Cardíaco , Feminino , Átrios do Coração , Humanos , Hipertensão Pulmonar/fisiopatologia , Pneumopatias Obstrutivas/fisiopatologia , Medidas de Volume Pulmonar , Masculino , Pessoa de Meia-Idade , Artéria Pulmonar/fisiopatologia , Fibrose Pulmonar/fisiopatologia , Ventilação Pulmonar , Pressão Propulsora Pulmonar , Resistência Vascular
18.
Chest ; 117(6): 1713-9, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10858407

RESUMO

STUDY OBJECTIVE: To compare hemodynamics and plasma big endothelin levels in patients awaiting heart transplantation who are receiving continuous IV therapy, and to establish their respective potency for predicting future cardiac events. DESIGN: A randomized, prospective trial of ambulatory continuous treatment with IV prostaglandin E(1) (PGE(1)) vs dobutamine. A subanalysis was conducted of all patients who completed 4 weeks of follow-up in regard to treatment effects on hemodynamics and big endothelin plasma levels. PATIENTS: Thirty-two listed heart transplant candidates who were refractory to oral treatment, 21 patients who were receiving PGE(1), and 11 patients receiving dobutamine. MEASUREMENTS AND RESULTS: Hemodynamics and plasma big endothelin levels were measured at baseline and after 4 weeks. The cardiac index increased significantly (PGE(1) group, 1.7 +/- 0.4 vs 2.5 +/- 0.6 L/min/m(2); dobutamine group, 1.8 +/- 0.3 vs 2.3 +/- 0.6 L/min/m(2); p < 0.05), whereas the systemic vascular resistance index (SVRI) decreased significantly only in the PGE(1) group (3,352 +/- 954 vs 2,178 +/- 519 dyne. s. cm(-5)/m(2); p < 0. 05). The plasma big endothelin level decreased significantly (PGE(1) group, 7.6 +/- 3.1 vs 4.7 +/- 2.6 fmol/mL; dobutamine group, 6.5 +/- 3.7 vs 5.0 +/- 2.6 fmol/mL; p < 0.01 for the time effect). Plasma big endothelin (beta = 0.393; chi(2) = 10.8; p = 0.001) and SVRI (beta = 0.003; chi(2) = 6.9; p < 0.01), both measured after 4 weeks of continuous treatment, were the only independent predictors of future outcome. CONCLUSION: Continuous treatment over 4 weeks with either PGE(1) or dobutamine in patients awaiting heart transplantation yields an improved hemodynamic state accompanied by a reduction of increased big endothelin levels. Plasma big endothelin measured after 4 weeks of continuous therapy provides prognostic information about future outcome.


Assuntos
Alprostadil/administração & dosagem , Cardiotônicos/administração & dosagem , Dobutamina/administração & dosagem , Endotelinas/sangue , Insuficiência Cardíaca/tratamento farmacológico , Hemodinâmica/efeitos dos fármacos , Precursores de Proteínas/sangue , Vasodilatadores/administração & dosagem , Adulto , Idoso , Alprostadil/efeitos adversos , Assistência Ambulatorial , Cardiotônicos/efeitos adversos , Dobutamina/efeitos adversos , Endotelina-1 , Feminino , Insuficiência Cardíaca/mortalidade , Insuficiência Cardíaca/fisiopatologia , Transplante de Coração , Humanos , Infusões Intravenosas , Assistência de Longa Duração , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Taxa de Sobrevida , Resistência Vascular/efeitos dos fármacos , Vasodilatadores/efeitos adversos
19.
J Heart Lung Transplant ; 17(4): 356-62, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9588580

RESUMO

The cytokines tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) are increased in the circulation of patients with chronic heart failure. However, their correlation with left ventricular dysfunction has not yet been thoroughly evaluated, and their interrelation with other neurohumoral systems, such as the adrenergic system and endothelin, is unclear. Therefore TNF-alpha, its soluble receptor II, IL-6, big endothelin, and noradrenaline levels were simultaneously measured in venous blood from 65 patients with heart failure in New York Heart Association (NYHA) class II to IV during therapy with digitalis, furosemide, and enalapril. TNF-alpha plasma levels were 3.2+/-0.2 SEM pg/ml in 38 patients in NYHA function class II, 4.0+/-0.3 SEM pg/ml in 16 patients in NYHA function class III, and 5.3+/-0.9 SEM pg/ml in 11 patients in NYHA function class IV (p < 0.001 vs NYHA function class II). IL-6 plasma levels were 3.1+/-0.6 SEM pg/ml in 38 patients in NYHA function class II, 5.2+/-0.8 SEM pg/ml in 16 patients in NYHA function class III, and 13.3+/-3.9 SEM pg/ml in 11 patients in NYHA function class IV (p < 0.0001 vs NYHA function class II andp < 0.0001 vs NYHA class III). Thus both cytokines increased with increasing severity of heart failure, but only IL-6 plasma levels were different in patients in the more severe function classes. TNF-alpha correlated closely with TNF soluble receptor II (r = 0.8, p < 0.0001) and modestly with serum creatinine (r = 0.6, p < 0.0001), whereas IL-6 plasma levels were not statistically related to kidney function. Significant modest correlations were also found among TNF-alpha and IL-6 (r = 0.3, p < 0.01), big endothelin (r = 0.3, p < 0.01), and noradrenaline levels (r = 0.4, <0.001). This study supports the hypothesis that in heart failure both cytokines, TNF-alpha, and IL-6, as well as neurohumoral factors, play a role in the clinical progression of the disease. Thereby levels of TNF-alpha but not IL-6 seem to be related to concomitant kidney dysfunction.


Assuntos
Insuficiência Cardíaca/sangue , Interleucina-6/sangue , Neurotransmissores/sangue , Receptores do Fator de Necrose Tumoral/sangue , Fator de Necrose Tumoral alfa/análise , Agonistas Adrenérgicos/sangue , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Anti-Hipertensivos/uso terapêutico , Cardiotônicos/uso terapêutico , Doença Crônica , Creatinina/sangue , Glicosídeos Digitálicos/uso terapêutico , Progressão da Doença , Diuréticos/uso terapêutico , Enalapril/uso terapêutico , Endotelina-1 , Endotelinas/sangue , Feminino , Furosemida/uso terapêutico , Insuficiência Cardíaca/classificação , Insuficiência Cardíaca/tratamento farmacológico , Humanos , Rim/fisiopatologia , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Norepinefrina/sangue , Precursores de Proteínas/sangue , Disfunção Ventricular Esquerda/sangue
20.
J Heart Lung Transplant ; 19(10): 939-45, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11044687

RESUMO

BACKGROUND: Selection of patients for urgent heart transplantation who have end-stage heart failure requires objective criteria to distinguish between subjects who may deteriorate clinically and those who can be stabilized. This population appears to differ in terms of right ventricular function, and right ventricular changes in loading may provide prognostic information. To investigate predictive parameters of patients admitted for urgent heart transplantation, we prospectively studied the mechanical performance of the right ventricle during acute afterload reduction. PATIENTS AND METHODS: We studied 68 heart failure patients hospitalized for bridge-to-transplant. The patients underwent right heart catherization at baseline and during prostaglandin E1 infusion. We stratified patients according to clinical outcome: Group A comprised patients who could be weaned from bridging therapy or who were electively transplanted after at least 90 days, and Group B comprised patients who died or who remained unstable and required transplant under urgent conditions. RESULTS: Right ventricular hemodynamics at baseline were comparable in both groups. However, during maximal vasodilatation, with prostaglandin E1 infusion, the right ventricular end-diastolic volume index (EDVI) was significantly reduced in Group A, (-23 ml/m(2) (p < 0.01) vs +12 ml/m(2) (p = n.s. DeltaEDVI in Group B. Reduction of EDVI by less than 10% during prostaglandin E1 infusion has a sensitivity of 89% and a specificity of 70% for clinical deterioration. CONCLUSIONS: The response of right ventricular volumes to prostaglandin E1 may predict the outcome of patients with severe congestive heart failure listed for urgent heart transplantation.


Assuntos
Alprostadil/uso terapêutico , Insuficiência Cardíaca/fisiopatologia , Vasodilatadores/uso terapêutico , Função Ventricular Direita , Idoso , Feminino , Insuficiência Cardíaca/mortalidade , Insuficiência Cardíaca/cirurgia , Hemodinâmica/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Seleção de Pacientes , Valor Preditivo dos Testes , Prognóstico , Estudos Prospectivos
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