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1.
J Pathol ; 191(4): 376-86, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10918212

RESUMO

The mechanisms involved in stromal reactions and fibrosis in solid malignant tumours are incompletely understood. In the present study, collagen type I production was investigated in tissues and cell lines derived from human undifferentiated (anaplastic) thyroid carcinomas, a highly aggressive, often fibrotic malignancy with mesenchymal phenotype. In situ hybridization showed the expression of pro-alpha1(I) collagen mRNA throughout the stromal part of the tumours. However, immunofluorescence staining using an anti-pro-collagen type I antibody revealed the synthesis of pro-collagen type I protein mainly in stromal cells juxtaposed to nests of tumour cells. In one out of five tissue samples from human undifferentiated thyroid carcinomas, pro-alpha1(I) collagen mRNA expression was also found in a small number of tumour cells. Several well-characterized cell lines established from undifferentiated thyroid carcinomas, two from tumours included in the present study, expressed both pro-alpha1(I) collagen and prolyl 4-hydroxylase mRNA, and three of these cell lines also synthesized native triple-helical collagen type I. Taken together, these data suggest that stromal fibroblasts are the main producers of collagen type I in anaplastic thyroid tumours. The carcinoma cells seem to play a regulatory role, stimulating the synthesis of collagen type I protein in the surrounding stroma by increasing pro-alpha1(I) collagen mRNA translation. However, collagen type I production by the carcinoma cells might also contribute to the marked desmoplasia commonly seen in these tumours.


Assuntos
Carcinoma/metabolismo , Colágeno/biossíntese , Neoplasias da Glândula Tireoide/metabolismo , Northern Blotting , Carcinoma/patologia , Colagenases/metabolismo , Fibrose , Imunofluorescência , Humanos , Hibridização In Situ , RNA Mensageiro , Neoplasias da Glândula Tireoide/patologia , Células Tumorais Cultivadas
2.
Eur J Endocrinol ; 138(1): 104-12, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9461325

RESUMO

OBJECTIVE: To evaluate the integrin pattern in the normal thyroid gland and in different pathological disorders including malignant tumors, because the aggressiveness of several malignant tumors correlates with alterations in the expression of one or more integrins. DESIGN: We examined the expression of integrins and E-cadherin immunohistochemically in a large and well-defined sample of normal and pathological human thyroid tissue. METHODS: Cryosections of 58 thyroid tissue specimens from normal tissue, thyrotoxicosis, nodular goiter, oxyphilic adenoma, follicular adenoma, follicular carcinoma, papillary carcinoma and anaplastic carcinoma, and three lymph node metastases were investigated immunohistochemically using monoclonal antibodies specifically recognizing the integrin beta1-, beta4-, alpha1-, alpha2-, alpha3-, alpha5- and alpha6-subunits, or E-cadherin. RESULTS: All thyroid epithelial cells expressed integrin beta1- and alpha3-subunits. Immunostaining of the beta4-subunit and the alpha6-subunits was found only in tumors. The staining pattern in the three lymph node metastases from papillary carcinomas did not differ from that in their primaries. Anaplastic carcinomas demonstrated neoexpression of the integrin alpha2-subunit. E-cadherin was detected in all tissues except anaplastic carcinomas. CONCLUSIONS: Neoexpression of alpha6beta4 was seen in most malignant tumors, whereas alpha2 was exclusively found in anaplastic carcinomas. In the latter, a loss of E-cadherin expression was also seen. These changes in cell adhesion molecule expression strongly suggest an association with the acquisition of proliferative and invasive properties.


Assuntos
Carcinoma/metabolismo , Integrinas/metabolismo , Glândula Tireoide/metabolismo , Neoplasias da Glândula Tireoide/metabolismo , Caderinas/metabolismo , Capilares/metabolismo , Imunofluorescência , Humanos , Imuno-Histoquímica , Receptores de Colágeno , Glândula Tireoide/irrigação sanguínea , Glândula Tireoide/citologia
3.
Genomics ; 37(3): 303-9, 1996 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-8938442

RESUMO

We have applied a solid support for parallel handling and direct loading of sequencing reactions--manifold sequencing--to analyze the coding sequence for the deficient copper transporting P-type ATPase in 24 families with Wilson disease. At least 100 different amplification reactions could be handled in parallel, with a minimal turnaround time of 12 h from isolated genomic DNA to identification of the mutations. Sixteen different mutations were found, accounting for 92% of the mutant genes. Ten of these mutations have not been previously described. Eleven were observed only in single families. Mutation His1069Gln, previously identified as the most prevalent mutation in Northern Europe, was found in one-third of the Northern European chromosomes in our material. Four patients were homozygous for this mutation, and three were homozygous for Thr977Met. The method allowed us to establish the diagnosis of Wilson disease in 24 h in a patient with acute hepatic failure.


Assuntos
Adenosina Trifosfatases/genética , Proteínas de Transporte/genética , Proteínas de Transporte de Cátions , Análise Mutacional de DNA/métodos , Degeneração Hepatolenticular/genética , Mutação Puntual , Análise de Sequência de DNA/métodos , Adolescente , Adulto , Idade de Início , Criança , ATPases Transportadoras de Cobre , Análise Mutacional de DNA/instrumentação , Enzimas de Restrição do DNA , Éxons/genética , Feminino , Degeneração Hepatolenticular/complicações , Degeneração Hepatolenticular/diagnóstico , Degeneração Hepatolenticular/epidemiologia , Humanos , Falência Hepática/etiologia , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Análise de Sequência de DNA/instrumentação
4.
Histopathology ; 28(3): 221-7, 1996 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8729040

RESUMO

Expression of the epidermal growth factor receptor (EGFR) was studied in cryosections from human thyroid tissues. Normal tissue (4 cases), nodular goitre (12), toxic goitre (9), adenoma (9), follicular carcinoma (1), papillary carcinoma (7) and poorly differentiated carcinoma (1) were used for immunohistochemistry. Northern blot analysis was performed in two nodular goitres, three adenomas, two papillary carcinomas, one follicular carcinoma and the adjacent normal tissue in five cases as well as in two cell lines from anaplastic carcinomas. Epidermal growth factor receptor immunoreactivity was detected in all tissues examined. The amount of EGFR mRNA did not differ between normal and abnormal tissues. However, the EGFR staining was weaker in normal thyroid tissue compared to the adjacent neoplastic areas suggesting an upregulation at the posttranslational level in the latter. A strong staining was also seen in hyperfunctioning thyroid glands. The EGFR location was mainly basal or basolateral in all thyroid tissues with normal histology and in toxic diffuse goitre. Pericellular and sometimes cytoplasmatic staining was seen in neoplastic tissues. In nodular goitre the staining was both basal, lateral and apical and varied in intensity. Our data suggest that a non-polarized location of EGFR probably indicates a loss of the normal epithelial cell polarity and could be interpreted as an early sign of dedifferentiation. Furthermore, a role for the EGFR is proposed, not only in the development of thyroid neoplasias but also in goitre formation.


Assuntos
Receptores ErbB/análise , Doenças da Glândula Tireoide/metabolismo , Doenças da Glândula Tireoide/patologia , Glândula Tireoide/química , Glândula Tireoide/patologia , Adenocarcinoma Folicular/química , Adenocarcinoma Folicular/patologia , Northern Blotting , Carcinoma Papilar/química , Carcinoma Papilar/patologia , Diferenciação Celular , Humanos , Imuno-Histoquímica , Neoplasias da Glândula Tireoide/química , Neoplasias da Glândula Tireoide/patologia
5.
Exp Cell Res ; 220(2): 257-65, 1995 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7556432

RESUMO

The regulation of growth and migration of thyroid follicular cells by epidermal growth factor (EGF) and transforming growth factor-beta (TGF-beta 1) were studied in primary cultures of porcine thyroid follicles embedded in collagen gel. Cultures were exposed to growth factors and [3H]thymidine (1 microCi/ml) for 3 days and then examined by light microscopic autoradiography. EGF at 1 ng/ml increased the [3H]thymidine labeling index from approximately 1% (control value) to 60% and stimulated fivefold the number of cells invading the collagen matrix. Intermediate responses were seen after treatment with 0.1 ng/ml of EGF. EGF-stimulated [3H]thymidine incorporation was reduced by TGF-beta 1 at concentrations above 0.1 ng/ml. In contrast, TGF-beta 1, which alone only had a minor stimulatory effect on cell motility, markedly promoted the migratory response to EGF (1 ng/ml). Thus, 0.1 ng/ml TGF-beta 1 doubled the fraction of migrating cells without changing the level of [3H]thymidine incorporation. Moreover, cell migration was still fourfold over control values in cultures exposed to 1.0 ng/ml EGF and 1.0 ng/ml TGF-beta 1, despite a strongly inhibited [3H]thymidine labeling. The number of microfollicles located peripherally to the mother follicles was increased synergistically by EGF and TGF-beta 1. The epithelium of mother follicles became grossly discontinuous in regions of intense cell migration induced by EGF and TGF-beta 1 in combination. In conclusion, TGF-beta 1 modulates the response of porcine thyrocytes to EGF in collagen gel cultures by promoting cell migration along with inhibition of [3H]thymidine incorporation. This suggests that EGF stimulates cell motility independent of the mitogenic signal. The persistent loss of epithelial integrity during enhanced cell migration indicates that mechanisms of intercellular adhesiveness are down-regulated by TGF-beta 1 and EGF in cooperation.


Assuntos
Fator de Crescimento Epidérmico/farmacologia , Glândula Tireoide/citologia , Glândula Tireoide/fisiologia , Fator de Crescimento Transformador beta/farmacologia , Animais , Autorradiografia , Membrana Celular/efeitos dos fármacos , Membrana Celular/ultraestrutura , Movimento Celular/efeitos dos fármacos , Células Cultivadas , Colágeno , DNA/biossíntese , Relação Dose-Resposta a Droga , Interações Medicamentosas , Índice Mitótico , Suínos , Timidina/metabolismo , Glândula Tireoide/efeitos dos fármacos , Trítio
6.
QJM ; 88(9): 609-16, 1995 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7583074

RESUMO

Long-term treatment with triethylene tetramine dihydrochloride, (trientine, TETA) was evaluated in 19 patients with Wilson's disease (WD). Two were given the drug as first choice and 17 after treatment with penicillamine. The change was made because of side-effects, lack of improvement or worsening of neurological symptoms. All penicillamine-induced side-effects reverted. Thirteen patients still receive trientine, and the mean total observation time on this treatment is 8.5 years/patient. Seven of the 13 are free from symptoms related to WD, five have mild to moderate neurological symptoms, mainly dysarthria. One patient with neurological symptoms who received trientine from the start of treatment deteriorated rapidly and is now severely dystonic. The symptoms initially worsened and later improved in one patient. All other patients improved during trientine treatment. Three patients died: two from a multifocal cancer including the liver and one non-complier from a ruptured spleen. Two patients underwent liver transplantation for progressive liver failure: one non-complier and one with liver cirrhosis whose liver function deteriorated despite treatment; both are now free from symptoms. Unexpectedly, two patients developed a serious colitis, one with duodenitis as well, that improved after withdrawal of the drug. No other unfavourable effects of trientine were recorded.


Assuntos
Quelantes/uso terapêutico , Degeneração Hepatolenticular/tratamento farmacológico , Trientina/uso terapêutico , Adolescente , Adulto , Biópsia , Criança , Colo/patologia , Esquema de Medicação , Duodeno/patologia , Feminino , Seguimentos , Degeneração Hepatolenticular/patologia , Humanos , Mucosa Intestinal/patologia , Fígado/patologia , Masculino , Penicilamina/efeitos adversos , Penicilamina/uso terapêutico
7.
Acta Obstet Gynecol Scand ; 73(5): 393-8, 1994 May.
Artigo em Inglês | MEDLINE | ID: mdl-8009970

RESUMO

Calcium homeostasis was longitudinally followed in serum and urine throughout normal pregnancy and the puerperium in 23 healthy women. From the 14th week of gestation, samples were obtained every fourth week until the 38th week. Post partum samples were obtained on the fifth day and after eight weeks. In the serum the total calcium decreased continuously during pregnancy. The ionized calcium and phosphate levels remained unchanged and within the reference interval for non-pregnant women. The alkaline phosphatase level progressively increased and high levels were found at term. The magnesium and hematocrit values remained below, whereas the calcitonin level remained just above the reference interval throughout pregnancy. The parathyroid hormone was low initially and increased towards term but within the reference interval. The urine excretion of calcium was constantly high, close to the upper reference limit, and renal function was slightly improved. At the last sampling eight weeks after delivery, all values were within normal limits for non-pregnant women. Calcium homeostasis is considerably changed during pregnancy and non-pregnant reference limits are not often valid.


Assuntos
Cálcio/metabolismo , Homeostase , Período Pós-Parto/metabolismo , Gravidez/metabolismo , Adolescente , Adulto , Fosfatase Alcalina/metabolismo , Análise de Variância , Calcitonina/metabolismo , Feminino , Hematócrito , Humanos , Estudos Longitudinais , Magnésio/metabolismo , Hormônio Paratireóideo/metabolismo , Fósforo/metabolismo , Valores de Referência , Reprodutibilidade dos Testes , Fatores de Tempo
8.
Am J Obstet Gynecol ; 170(5 Pt 1): 1315-20, 1994 May.
Artigo em Inglês | MEDLINE | ID: mdl-8178860

RESUMO

OBJECTIVE: We studied the effect of long-term heparin treatment on bone mass during pregnancy. STUDY DESIGN: Thromboprophylaxis with heparin was given to 39 women during pregnancy for a mean of 28 weeks and for an average of 6 weeks post partum. Bone mineral density measured with single-photon absorptiometry of the distal and ultradistal parts of the forearm was determined at the time of the start of heparin treatment (mean, twelfth week of gestation), immediately post partum, and on average 7 weeks post partum. The mean dosage of heparin was 17,300 IU/day. A control group of 34 normal pregnant women was studied for comparison. RESULTS: In women treated with heparin, there was almost a 5% reduction in trabecular bone during pregnancy (p < 0.01) and an insignificant recovery post partum. There were no significant changes in bone mass during pregnancy or in the puerperium in the control group. CONCLUSION: Long-term treatment with heparin during pregnancy is associated with bone loss, but indications of reversible changes are observed.


Assuntos
Densidade Óssea/efeitos dos fármacos , Heparina/farmacologia , Adulto , Estudos de Casos e Controles , Feminino , Heparina/uso terapêutico , Humanos , Período Pós-Parto/fisiologia , Gravidez/fisiologia , Estudos Prospectivos
9.
Am J Obstet Gynecol ; 168(4): 1265-70, 1993 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8475973

RESUMO

OBJECTIVE: To study the effect of long-term treatment during gestation with heparin on the incidence of osteoporotic fractures and thromboembolic recurrence. STUDY DESIGN: Long-term subcutaneous prophylaxis with heparin twice daily in pregnancy was prescribed for 184 women, during a decade because of an increased risk of thromboembolism. The dosage of heparin was adjusted to anti-factor Xa activity or activated partial thromboplastin time and different regimens were given, depending on the risk of recurrence. RESULTS: For the total group the mean dosage of heparin ranged from 13,000 to 40,000 IU per 24 hours (mean 19,100 IU per 24 hours), and the average duration of treatment was 25 weeks. Symptomatic osteoporotic fractures of the spine occurred post partum in four women, for whom the mean dosage of heparin ranged from 15,000 to 30,000 IU per 24 hours (mean 24,500 IU per 24 hours), and the duration of treatment ranged from 7 to 27 weeks (mean 17 weeks). In spite of prophylaxis with heparin, thromboembolic complications occurred in five women. They had either nonsatisfactory concentrations of heparin according to our regimen or were later diagnosed as having a coagulation disorder known to increase the risk of thromboembolism. CONCLUSION: Osteoporotic vertebral fractures were found in 2.2% of the women, and a relationship to the amount of heparin was indicated, although fractures were not avoided during low-dose, short-term prophylaxis. Recurrence of thromboembolism occurred in 2.7% of the patients, but if a strict heparin adjustment had been performed, recurrence could probably have been prevented.


Assuntos
Heparina/efeitos adversos , Osteoporose/complicações , Complicações na Gravidez/prevenção & controle , Transtornos Puerperais/prevenção & controle , Fraturas da Coluna Vertebral/etiologia , Tromboembolia/prevenção & controle , Esquema de Medicação , Feminino , Hemorragia/induzido quimicamente , Heparina/administração & dosagem , Humanos , Gravidez , Complicações na Gravidez/etiologia , Transtornos Puerperais/etiologia , Recidiva , Tromboembolia/etiologia
10.
Br J Obstet Gynaecol ; 99(5): 412-6, 1992 May.
Artigo em Inglês | MEDLINE | ID: mdl-1622915

RESUMO

OBJECTIVE: To investigate the effect of subcutaneous heparin treatment on calcium homeostasis in pregnancy. DESIGN: A longitudinal case-control observational study. SETTING: Department of Obstetrics and Gynaecology, Karolinska Hospital, Stockholm, Sweden. SUBJECTS: 36 pregnant women with previously verified thromboembolic complications and 23 healthy pregnant control women similar in age, parity, weight, and smoking habit. INTERVENTIONS: Thromboprophylaxis during pregnancy and 6 weeks post partum was given with subcutaneous heparin twice daily to the 36 women with a history of thromboembolic complications, 16 received an average dose of 24,500 IU/day and 20 a mean dose of 17,300 IU/day. Venous blood and urine samples were obtained every 4 weeks. MAIN OUTCOME MEASURES: Serum concentrations of total calcium, ionized calcium, calcitonin and urinary calcium. RESULTS: Women on high-dose heparin treatment showed significantly higher concentrations of total and ionized calcium and of calcitonin in serum and significantly lower concentrations of calcium in urine than did 23 normal pregnant controls. The differences were most pronounced in the third trimester. The results obtained in the low-dose heparin group were between those in the high-dose and the control groups. At 8 weeks postpartum there were no significant differences between the heparin-treated women and the controls. No significant differences were found during pregnancy in haematocrit, liver or renal function, serum levels of albumin, phosphate, magnesium, alkaline phosphatase, parathyroid hormone or urinary cyclic AMP. CONCLUSIONS: Heparin treatment during pregnancy results in changes in calcium homeostasis and a dose-dependent response is suggested.


Assuntos
Cálcio/metabolismo , Heparina/uso terapêutico , Complicações Cardiovasculares na Gravidez/tratamento farmacológico , Tromboembolia/tratamento farmacológico , Adulto , Calcitonina/sangue , Estudos de Casos e Controles , Relação Dose-Resposta a Droga , Feminino , Homeostase/efeitos dos fármacos , Humanos , Estudos Longitudinais , Gravidez , Complicações Cardiovasculares na Gravidez/metabolismo , Tromboembolia/metabolismo
12.
Br J Obstet Gynaecol ; 97(3): 221-8, 1990 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-2110467

RESUMO

Osteopenia, sometimes with compression fractures of the spine, is a side-effect of long-term heparin treatment. The frequency is unknown. In this study, 70 women were given subcutaneous heparin as therapy for, or prophylaxis against, thromboembolism during pregnancy. All, except two, were examined by X-ray of the spine and hip first week post partum. The duration of treatment and the dosage of heparin varied. There were 12 (17%) with obvious osteopenia, including two women with multiple fractures of the spine (3%). Re-examination 6-12 months post partum showed that the changes were reversible in most cases. Another 18 women were examined about three years after heparin treatment during pregnancy. No obvious osteopenia was found among them or in a control group of 30 women examined in the first week post partum. The degree of osteopenia was not correlated with either the heparin dose or the duration of treatment. Women treated with heparin in consecutive pregnancies do not seem to have an increased risk of osteopenia.


Assuntos
Doenças Ósseas Metabólicas/induzido quimicamente , Heparina/efeitos adversos , Complicações na Gravidez/induzido quimicamente , Adulto , Doenças Ósseas Metabólicas/diagnóstico por imagem , Feminino , Fraturas Ósseas/diagnóstico por imagem , Heparina/uso terapêutico , Quadril/diagnóstico por imagem , Humanos , Incidência , Assistência de Longa Duração , Gravidez , Complicações na Gravidez/diagnóstico por imagem , Complicações Cardiovasculares na Gravidez/prevenção & controle , Radiografia , Fatores de Risco , Doenças da Coluna Vertebral/diagnóstico por imagem , Coluna Vertebral/diagnóstico por imagem , Tromboembolia/prevenção & controle
13.
Am J Obstet Gynecol ; 161(2): 420-5, 1989 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-2764060

RESUMO

Twenty-six pregnant women were given prophylactic heparin treatment because of previous thromboembolic complications. The mean duration of treatment was 25 weeks (range, 6 to 32 weeks). The amount of heparin was adjusted to a plasma concentration of 0.08 to 0.15 IU/ml, measured as anti-factor Xa activity. This effect was compared with that on activated partial thromboplastin time. The average dose was 16,400 IU/24 hours or 225 IU/kg of body weight per 24 hours. When the plasma concentration was within the stipulated range, the dose was 234 IU/kg of body weight/24 hours. No significant prolongation of activated partial thromboplastin time was found in two thirds of the samples. Blood coagulation was either not activated or only slightly activated, as verified by a low level of fibrinopeptide A. Platelet counts and antithrombin III levels were generally not depressed. No thromboembolic complications occurred during the pregnancies or puerperium. Bleeding during delivery was not increased. No fractures of the spine caused by osteoporosis were found on radiologic examination post partum.


Assuntos
Heparina/administração & dosagem , Complicações Cardiovasculares na Gravidez/prevenção & controle , Tromboembolia/prevenção & controle , Adulto , Antitrombina III/análise , Fator Xa , Feminino , Fibrinopeptídeo A/análise , Heparina/sangue , Humanos , Injeções Subcutâneas , Tempo de Tromboplastina Parcial , Contagem de Plaquetas/efeitos dos fármacos , Gravidez , Complicações Cardiovasculares na Gravidez/sangue , Autoadministração , Inibidores de Serina Proteinase , Tromboembolia/sangue
14.
Gynecol Obstet Invest ; 20(1): 37-44, 1985.
Artigo em Inglês | MEDLINE | ID: mdl-3930349

RESUMO

Blood coagulation and fibrinolysis variables have been studied in the normal puerperium in order to facilitate the decision to discontinue thrombosis prophylaxis after delivery. 16 women were followed longitudinally from the 1st to the 6th week post partum. Factor VIII activity and related antigen, fibrinogen, fibrinopeptide A, antithrombin III, plasminogen, tissue plasminogen activator (t-PA), fast inhibitor of t-PA, alpha 2-antiplasmin, urokinase inhibitors, fragment B beta 15-42 and kallikrein inhibition were analyzed. Both blood coagulation and fibrinolysis were significantly increased during the first 2 weeks, although simultaneously increased inhibitor capacity of both systems was present. 3 weeks post partum, blood coagulation and fibrinolysis were generally normalized, although the inhibitors remained raised compared to nonpregnant controls throughout the observation period.


Assuntos
Coagulação Sanguínea , Fibrinólise , Período Pós-Parto , Antígenos/análise , Antitrombina III/análise , Fator VIII/análise , Fator VIII/imunologia , Feminino , Fibrinogênio/análise , Fibrinopeptídeo A/análise , Humanos , Gravidez , Valores de Referência , Fator de von Willebrand/análise
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