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1.
Internist (Berl) ; 53(3): 341-4, 2012 Mar.
Artigo em Alemão | MEDLINE | ID: mdl-22189462

RESUMO

We report the case of a 47-year-old man who was admitted because of syncope. Upon hospital admission, he rapidly developed circulatory shock with generalized edema and a severe hemoconcentration with a hematocrit of 70%. The condition was stabilized with infusion of 17 l of cristalloid fluids over a period of 24 h. After ruling out possible secondary causes, the diagnosis of a systemic capillary leak syndrome--a severe transient endothelial barrier dysfunction of unknown origin--was made. A triad of hypotension, hemoconcentration (hematocrit >60%) and macromolecular extravasation is the typical finding; furthermore, a strong association with monoclonal gammopathy of unknown significance (MGUS) is described.


Assuntos
Síndrome de Vazamento Capilar/diagnóstico , Síndrome de Vazamento Capilar/terapia , Edema/diagnóstico , Edema/terapia , Choque/diagnóstico , Choque/terapia , Diagnóstico Diferencial , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
2.
Rapid Commun Mass Spectrom ; 25(16): 2355-60, 2011 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-21766378

RESUMO

Measurements of δ(13)C in CO(2) have traditionally relied on samples stored in sealed vessels and subsequently analyzed using magnetic sector isotope ratio mass spectrometry (IRMS), an accurate but expensive and high-maintenance analytical method. Recent developments in optical spectroscopy have yielded instruments that can measure δ(13)CO(2) in continuous streams of air with precision and accuracy approaching those of IRMS, but at a fraction of the cost. However, continuous sampling is unsuited for certain applications, creating a need for conversion of these instruments for batch operation. Here, we present a flask (syringe) adaptor that allows the collection and storage of small aliquots (20-30 mL air) for injection into the cavity ring-down spectroscopy (CRDS) instrument. We demonstrate that the adaptor's precision is similar to that of traditional IRMS (standard deviation of 0.3‰ for 385 ppm CO(2) standard gas). In addition, the concentration precision (±0.3% of sample concentration) was higher for CRDS than for IRMS (±7% of sample concentration). Using the adaptor in conjunction with CRDS, we sampled soil chambers and found that soil-respired δ(13)C varied between two different locations in a piñon-juniper woodland. In a second experiment, we found no significant discrimination between the respiration of a small beetle (~5 mm) and its diet. Our work shows that the CRDS system is flexible enough to be used for the analysis of batch samples as well as for continuous sampling. This flexibility broadens the range of applications for which CRDS has the potential to replace magnetic sector IRMS.


Assuntos
Dióxido de Carbono/análise , Isótopos de Carbono/análise , Espectrometria de Massas/métodos , Solo/química , Animais , Testes Respiratórios/métodos , Calibragem , Dióxido de Carbono/química , Dióxido de Carbono/metabolismo , Besouros/metabolismo , Análise dos Mínimos Quadrados , Pinus , Reprodutibilidade dos Testes , Estatísticas não Paramétricas
3.
Acta Neurochir Suppl ; 91: 79-87, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15707029

RESUMO

Although efficacy of gamma knife radiosurgery has been demonstrated in numerous studies, the policies in patients with multiple metastases seem to be unequivocal. The maintained quality of life, the possibility of short hospitalization and the continuation of a systemic chemotherapy are increasingly important arguments in favor of a minimally invasive radiosurgical approach. These factors are particularly emphasized in patients with a dismal prognosis. The current retrospective analysis was undertaken to summarize the clinical results of radiosurgery in patients with multiple cerebral metastases of various primary cancer. Fractionated whole brain radiotherapy (WBRT) was omitted as prophylactic treatment and applied only in cases with general tumor spread. Clinical data of all consecutive patients (n = 215) who received gamma knife radiosurgery for cerebral metastases between January 2001 and January 2003 at the gamma knife Centers of the Karolinska Hospital and H.M. Queen Sophia Hospital (Sophiahemmet) Stockholm were analyzed retrospectively. 172 patients were treated for multiple metastases (198 treatments). The median prescription dose was 22 Gy (range 14-34 Gy). The Kaplan Meier plot shows a median survival (MST) of 7.8 months for patients with multiple cerebral metastases and 13.7 months for patients with single metastases. There was no relation between survival and number of metastases in patients with multiple metastases. Within this group 11.6% (20/172 patients) developed adverse radiation reactions. Tumor recurrences were documented by FDG-PET in 7 patients (out of 172 patients: 4.1%) after a median latency of 10 months after radiosurgery. In summary, gamma knife radiosurgery provides a highly effective and minimally invasive method to treat patients with multiple cerebral metastases even without prophylactic WBRT. Local control and patient survival in the present series of patients is in accordance with other retrospective series of patients with single and multiple metastases.


Assuntos
Neoplasias Encefálicas/secundário , Neuronavegação , Radiocirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/cirurgia , Feminino , Fluordesoxiglucose F18 , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/diagnóstico , Recidiva Local de Neoplasia/mortalidade , Tomografia por Emissão de Pósitrons , Estudos Retrospectivos , Análise de Sobrevida
4.
J Intern Med ; 253(4): 454-62, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12653875

RESUMO

OBJECTIVES: Radiation therapy to the pituitary gland means a considerable risk of developing hypopituitarism. The aim of the study was to investigate the growth hormone releasing hormone (GHRH)-growth hormone (GH)-insulin-like growth factor-I (IGF-I) axis after treatment with stereotactic radiosurgery to the pituitary because of Cushing's disease. SETTING: Inpatient ward in university clinic. SUBJECTS: Eleven adult patients (eight women, three men), 20-65 years of age were studied 2.5-11.3 years after stereotactic radiosurgery (isocentre dose 50-100 Gy lesion-1) and compared with healthy controls. MAIN OUTCOME MEASURES: Spontaneous GH secretion was evaluated as 12-h night GH profiles. Stimulated GH responses were evaluated in seven of 11 patients using arginine-insulin and GHRH tests. Serum IGF-I levels were measured in fasting serum morning samples. RESULTS: All patients except one displayed blunted nocturnal GH profiles. After arginine-insulin challenge, six of seven patients displayed low GH release. GH response was higher after GHRH injection compared with both the response to arginine-insulin and to the maximum GH levels in the nocturnal profiles. Seven patients had an IGF-I standard deviation score (SDS) within the normal range for age. Serum IGF-I values were correlated to mean GH values in the 12-h night profile (r = 0.67, P < 0.05) and both these variables were negatively correlated to time elapse since last radiation treatment (r = -0.64, P < 0.05 and r = -0.78, P < 0.05, respectively). CONCLUSIONS: Our patients with Cushing's disease evaluated several years after stereotactic radiosurgery as the primary and only treatment, demonstrated severely blunted spontaneous GH secretion and GH response to arginine-insulin. A disturbed regulation at the hypothalamic level was suggested as mechanism for this. Noteworthy is that serum IGF-I values correlated to the mean values of the 12-h GH profile.


Assuntos
Síndrome de Cushing/cirurgia , Hormônio do Crescimento Humano/deficiência , Sistema Hipotálamo-Hipofisário/efeitos da radiação , Hipófise/efeitos da radiação , Radiocirurgia/efeitos adversos , Adulto , Idoso , Arginina , Síndrome de Cushing/metabolismo , Feminino , Seguimentos , Hormônio Liberador de Hormônio do Crescimento/metabolismo , Hormônio do Crescimento Humano/metabolismo , Humanos , Sistema Hipotálamo-Hipofisário/fisiologia , Fator de Crescimento Insulin-Like I/metabolismo , Masculino , Pessoa de Meia-Idade , Hipófise/metabolismo
5.
Neurosurgery ; 49(2): 284-91; discussion 291-2, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11504104

RESUMO

OBJECTIVE: To study retrospectively long-term outcomes of patients with adrenocorticotropic hormone-producing pituitary tumors that were treated with stereotactic Leksell gamma knife unit radiosurgery. METHODS: Eighty-nine patients aged 5 to 67 years were treated between 1976 and 1985. Eighteen patients aged 18 to 68 years (mean age, 41 yr) were followed in detail. Fifteen patients were women. None had previously received conventional radiotherapy, but pituitary microsurgery had been performed in two patients, and one patient had had an adrenalectomy. In the remaining 15 patients, radiosurgery was the primary therapy. RESULTS: Sixty-four patients had one stereotactic treatment, and 25 patients had two or more treatments. No complications were observed during treatment and the immediate follow-up period. At follow-up, 17 patients had died 1 to 20 years after the first treatment. No deaths were related to the treatment. In our 18 patients, the follow-up time after the first radiosurgical treatment was 12 to 22 years (mean follow-up period, 17 yr). Urinary cortisol levels gradually normalized in 83% of the patients. No recurrences were observed. Pituitary hormone insufficiencies developed in about two of every three patients and occurred even more than 10 years after treatment. Eight patients had transient hyperprolactinemia. The patients' vision and visual fields were unaffected, and none of them had signs of radiation-induced side effects such as brain tumors or brain necrosis. CONCLUSION: Stereotactic radiosurgery is a safe and effective method in the treatment of patients with adrenocorticotropic hormone-producing pituitary tumors, and the effect of treatment is long-lasting. Stereotactic radiosurgery is mainly a complement to microsurgery because of its gradually appearing effect and the occurrence of pituitary insufficiency. New pituitary deficiencies may be found more than 10 years after treatment.


Assuntos
Hormônio Adrenocorticotrópico/metabolismo , Neoplasias Hipofisárias/metabolismo , Neoplasias Hipofisárias/cirurgia , Radiocirurgia , Técnicas Estereotáxicas , Adolescente , Adulto , Idoso , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Doenças da Hipófise/etiologia , Complicações Pós-Operatórias , Resultado do Tratamento
6.
J Neurooncol ; 54(2): 197-203, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11761436

RESUMO

No treatment modality has been entirely successful in the management of pituitary adenomas. Although most patients with pituitary microadenomas can be cured by transsphenoidal surgery, the results are less satisfactory in macroadenomas in particular with suprasellar and/or parasellar extension. Additional treatment is then called for. Conventional fractional radiotherapy can often control tumour growth but is limited to 45-50 Gy with a very slow reduction in elevated pituitary hormones and a high incidence of pituitary insufficiency. Stereotactic radiosurgery allows the delivery of radiation with high precision to the target with low doses to the surrounding tissues permitting higher radiation doses. Gamma knife radiosurgery using photon energy with gamma beams from multiple cobalt 60 radiation sources is now used in many centers. It can be carried out in an outpatient setting with one single treatment. A more rapid normalization of pituitary hormone hypersecretion than with conventional radiation can be achieved as well as arrest of tumour growth and reduction of tumour mass. We therefore consider gamma knife radiosurgery as a valuable compliment to pituitary surgery. Long-term prospective studies are needed to evaluate the frequency of pituitary insufficiency in patients where the target area is determined with stereotactic magnetic resonance imaging (MRI).


Assuntos
Adenoma/cirurgia , Neoplasias Hipofisárias/cirurgia , Radiocirurgia , Adenoma/metabolismo , Hormônio Adrenocorticotrópico/metabolismo , Hormônio do Crescimento Humano/metabolismo , Humanos , Neoplasias Hipofisárias/metabolismo , Prolactinoma/metabolismo , Prolactinoma/cirurgia , Radiocirurgia/efeitos adversos
7.
J Biol Chem ; 275(14): 10093-8, 2000 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-10744689

RESUMO

Phosphatidylinositol 3-kinase mediates several actions of insulin including its antilipolytic effect. This effect is elicited by the insulin-stimulated serine phosphorylation and activation of cGMP-inhibited phosphodiesterase (PDE3B). In human adipocytes, we found that insulin differentially stimulated phosphatidylinositol 3-kinase activity; the lipid kinase activity was associated with IRS-1, whereas the serine kinase activity was associated with the insulin receptor and phosphorylated a number of proteins including p85, p110, and a 135-kDa protein identified as PDE3B. PDE3B phosphorylation was associated with enzyme activation, thus initiating the antilipolytic effect of insulin. These results show a novel pathway for intracellular signaling through the insulin receptor leading to the serine phosphorylation of key proteins involved in insulin action.


Assuntos
3',5'-AMP Cíclico Fosfodiesterases/metabolismo , Tecido Adiposo/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Receptor de Insulina/fisiologia , 3',5'-AMP Cíclico Fosfodiesterases/isolamento & purificação , Tecido Adiposo/enzimologia , Células Cultivadas , Nucleotídeo Cíclico Fosfodiesterase do Tipo 3 , Ativação Enzimática , Humanos , Insulina/farmacologia , Insulina/fisiologia , Proteínas Substratos do Receptor de Insulina , Peso Molecular , Fosfatidilinositol 3-Quinases/isolamento & purificação , Fosfoproteínas/isolamento & purificação , Fosfoproteínas/metabolismo , Fosforilação , Proteínas Serina-Treonina Quinases/metabolismo , Receptor de Insulina/efeitos dos fármacos , Transdução de Sinais
8.
Science ; 278(5344): 1776-8, 1997 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-9388175

RESUMO

Nitrous oxide is a greenhouse gas that also plays a role in the cycling of stratospheric ozone. Air samples from the lower stratosphere exhibit 15N/14N and 18O/16O enrichment in nitrous oxide, which can be accounted for with a simple model describing an irreversible destruction process. The observed enrichments are quite large and incompatible with those determined for the main stratospheric nitrous oxide loss processes of photolysis and reaction with excited atomic oxygen. Thus, although no stratospheric source needs to be invoked, the data indicate that present understanding of stratospheric nitrous oxide chemistry is incomplete.

9.
J Biol Chem ; 272(34): 21520-6, 1997 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-9261171

RESUMO

Protein kinase B (PKB) (also referred to as RAC/Akt kinase) has been shown to be controlled by various growth factors, including insulin, using cell lines and transfected cells. However, information is so far scarce regarding its regulation in primary insulin-responsive cells. We have therefore used isolated rat adipocytes to examine the mechanisms, including membrane translocation, whereby insulin and the insulin-mimicking agents vanadate and peroxovanadate control PKB. Stimulation of adipocytes with insulin, vanadate, or peroxovanadate caused decreased PKB mobility on sodium dodecyl sulfate-polyacrylamide gels, indicative of increased phosphorylation, which correlated with an increase in kinase activity detected with the peptide KKRNRTLTK. This peptide was found to detect activated PKB selectively in crude cytosol and partially purified cytosol fractions from insulin-stimulated adipocytes. The decrease in electrophoretic mobility and activation of PKB induced by insulin was reversed both in vitro by treatment of the enzyme with alkaline phosphatase and in the intact adipocyte upon removal of insulin or addition of the phosphatidylinositol 3-kinase (PI 3-kinase) inhibitor wortmannin. Significant translocation of PKB to membranes could not be demonstrated after insulin stimulation, but peroxovanadate, which appeared to activate PI 3-kinase to a higher extent than insulin, induced substantial translocation. The translocation was prevented by wortmannin, suggesting that PI 3-kinase and/or the 3-phosphorylated phosphoinositides generated by PI 3-kinase are indeed involved in the membrane targeting of PKB.


Assuntos
Adipócitos/enzimologia , Insulina/fisiologia , Proteínas Serina-Treonina Quinases , Proteínas Proto-Oncogênicas/metabolismo , Vanadatos/farmacologia , Animais , Compartimento Celular , Membrana Celular/enzimologia , Citosol/enzimologia , Ativação Enzimática/efeitos dos fármacos , Masculino , Proteínas Proto-Oncogênicas c-akt , Ratos , Ratos Sprague-Dawley
10.
J Biol Chem ; 271(19): 11575-80, 1996 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-8626720

RESUMO

Stimulation of rat adipocytes with insulin and isoproterenol results in serine phosphorylation and activation of the adipocyte cGMP-inhibited phosphodiesterase (cGI PDE), events believed to be important in the antilipolytic action of insulin (Degerman, E., Smith, C.J., Tornqvist, H., Vasta, V., Manganiello, V.C., and Belfrage, P. (1990) Proc. Natl. Acad. Sci. U.S.A. 87,533-537). Here we demonstrate, by two-dimensional phosphopeptide mapping, that the major phosphopeptide generated by trypsin, or trypsin followed by Asp-N protease digestion of [32P]cGI PDE phosphorylated in adipocytes in response to isoproterenol and/or insulin, in each case co-migrates with the phosphopeptide released by the same treatment of M297FRRPS(P)LPCISREQ310. This peptide was synthesized based on the deduced sequence of the cloned rat adipocyte cGI PDE and phosphorylated by cAMP-dependent protein kinase (protein kinase A). Radiosequencing of authentic and synthetic tryptic 32P-peptides showed that a single site in cGI PDE (Ser302) was phosphorylated in adipocytes incubated with isoproterenol and/or insulin. The more than additive phosphorylation and activation of cGI PDE in response to the two hormones found in this report and previously (Smith, C.J., Vasta, V., Degerman, E., Belfrage, P., and Manganiello, V.C. (1991) J. Biol. Chem. 266, 13385-13390) is proposed to reflect cross-talk between their respective signal transduction pathways at the level of the cGI PDE serine protein kinase or upstream regulatory component(s).


Assuntos
3',5'-AMP Cíclico Fosfodiesterases/metabolismo , Adipócitos/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Insulina/farmacologia , Isoproterenol/farmacologia , 3',5'-AMP Cíclico Fosfodiesterases/química , Adipócitos/efeitos dos fármacos , Sequência de Aminoácidos , Animais , Nucleotídeo Cíclico Fosfodiesterase do Tipo 3 , Eletroforese em Gel Bidimensional , Eletroforese em Gel de Poliacrilamida , Cinética , Dados de Sequência Molecular , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/isolamento & purificação , Mapeamento de Peptídeos , Fosfopeptídeos/química , Fosfopeptídeos/isolamento & purificação , Fosforilação , Ratos
11.
Clin Mol Pathol ; 49(1): M51-6, 1996 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16696046

RESUMO

Aim-To examine a series of cyst fluid samples from patients with craniopharyngioma at various stages of treatment in order to evaluate the use of insulin-like growth factors (IGFs) and IGF binding proteins as tumour markers or indicators of successful treatment, or both.Methods-Cyst fluid samples were obtained by stereotactic puncture prior to the intracavitary application of (90)Yttrium and at subsequent occasions. Analysis was performed by gel chromatography, radio-immunoassays, binding studies, and sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) with subsequent western blotting.Results-IGF-I, -II and IGF binding protein-1 concentrations were measured in three craniopharyngioma cyst fluid samples. Immunoreactive IGF-I and IGF binding protein-1 concentrations in these three samples were between 6 and 29 ng/ml, and 17 and 48 ng/ml, respectively. In contrast, the IGF-II concentrations measured in 19 cyst fluid samples from seven patients with craniopharyngioma at various stages of treatment were much higher at 25-671 ng/ml. SDS-PAGE and subsequent western blotting using [(125)I]IGF-II as the ligand gave bands with estimated molecular weights of 330, 220, 135, 96, 46, 43, 34, 29, and 13.5 kDa in one adult, and identical bands at 220, 41.5, 37.5, 32, and 19 kDa in three cyst fluid samples from three children with craniopharyngioma.Conclusions-These results suggest that IGFs and IGF binding proteins are secreted by craniopharyngiomas and that they may alter the growth characteristics of these tumours. Furthermore, the distinct pattern of IGF binding protein sizes might be used as a tool for the differential diagnosis of tumours of the central nervous system.

12.
FEBS Lett ; 350(2-3): 314-8, 1994 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-8070584

RESUMO

Incubation of rat adipocytes with wortmannin, a potent and selective phosphatidylinositol 3-kinase (PI 3-kinase) inhibitor, completely blocked the antilipolytic action of insulin (IC50 = 100 nM), the insulin-induced activation and phosphorylation of cGMP-inhibited cAMP phosphodiesterase (cGI-PDE) as well as the activation of the insulin-stimulated cGI-PDE kinase (IC50 = 10-30 nM). No direct effects of the inhibitor on the insulin-stimulated cGI-PDE kinase, the cGI-PDE and the hormone-sensitive lipase were observed. These data suggest that activation of PI 3-kinase upstream of the insulin-stimulated cGI-PDE kinase in the antilipolytic insulin signalchain has an essential role for insulin-induced cGI-PDE activation/phosphorylation and anti-lipolysis.


Assuntos
3',5'-AMP Cíclico Fosfodiesterases/metabolismo , Androstadienos/farmacologia , Insulina/farmacologia , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , 3',5'-AMP Cíclico Fosfodiesterases/antagonistas & inibidores , Adipócitos/metabolismo , Animais , GMP Cíclico/farmacologia , Ativação Enzimática/efeitos dos fármacos , Lipólise/efeitos dos fármacos , Masculino , Fosfatidilinositol 3-Quinases , Fosforilação , Fosfotransferases (Aceptor do Grupo Álcool)/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/metabolismo , Ratos , Ratos Sprague-Dawley , Wortmanina
14.
Acta Radiol ; 35(3): 204-11, 1994 May.
Artigo em Inglês | MEDLINE | ID: mdl-8192953

RESUMO

The CSF flows in the aqueduct and at the foramen magnum were examined in 5 patients with communicating hydrocephalus (HC) and in 10 with benign intracranial hypertension (BIH) as well as in 5 healthy volunteers. As compared to normal individuals, the aqueductal flow in HC was about 10 times larger and the cervical flow was half as large. In BIH the CSF flows were not different from those of normal volunteers. The decreased arterial expansion as reflected in the reduced cervical flow in HC may be due to pathologic changes in the arteries and paravascular spaces. The large aqueductal flow in HC reflects a large brain expansion, causing increased transcerebral mantle pressure gradient and ventricular dilatation. In BIH there is a normal brain expansion (aqueductal flow) and consequently no ventricular dilatation. It is argued that BIH be caused by an obstruction on the venous side, as opposed to the vascular alterations in HC, which are on the arterial side.


Assuntos
Líquido Cefalorraquidiano/fisiologia , Hidrocefalia/fisiopatologia , Imageamento por Ressonância Magnética , Pseudotumor Cerebral/fisiopatologia , Adulto , Aqueduto do Mesencéfalo/patologia , Aqueduto do Mesencéfalo/fisiologia , Circulação Cerebrovascular , Feminino , Forame Magno/patologia , Forame Magno/fisiologia , Humanos , Hidrocefalia/patologia , Masculino , Pessoa de Meia-Idade , Pseudotumor Cerebral/patologia , Fluxo Pulsátil , Reologia
15.
Childs Nerv Syst ; 9(2): 100-3, 1993 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7686451

RESUMO

Insulin-like growth factor (IGF)-I, -II and IGF-binding proteins (IGFBPs) were demonstrated in the cyst fluid of a patient with a hypothalamic astrocytoma. The astrocytoma cyst fluid was subjected to gel chromatography at low pH and the IGF-I and IGF-II levels were measured by specific radioimmunoassays. Immunoreactive IGF-I and IGF-II levels were 19 ng/ml and 78 ng/ml respectively. Several-fold higher IGF-II values were obtained when cyst fluid was not extracted or was extracted with acid ethanol before radioimmunoassay analysis. The immunoreactive IGFBP-1 concentration was 26 ng/ml. Sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) and subsequent Western ligand blotting with [125I]IGF-II revealed bands at approximately 200, 34.5, 29.5, 24 and 21 kD as visualized by autoradiography. Binding studies demonstrated that these binding proteins bind specifically [125I]IGF-I and [125I]IGF-II. These observations suggest that IGFs as well as IGF-binding proteins are produced by astrocytoma cells and may act in a paracrine or autocrine fashion capable of modulating the growth of astrocytoma tumours.


Assuntos
Proteínas de Transporte/análise , Glioblastoma/química , Inibidores do Crescimento/análise , Neoplasias Hipotalâmicas/química , Fator de Crescimento Insulin-Like II/análise , Fator de Crescimento Insulin-Like I/análise , Western Blotting , Pré-Escolar , Cromatografia em Gel , Glioblastoma/cirurgia , Humanos , Neoplasias Hipotalâmicas/cirurgia , Proteínas de Ligação a Fator de Crescimento Semelhante a Insulina , Masculino , Radioimunoensaio
16.
Neurosurgery ; 29(5): 663-8, 1991 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-1961394

RESUMO

Stereotactic radiosurgery on the pituitary given with the cobalt-60 gamma unit was used in the treatment of 21 patients with growth hormone (GH)-producing pituitary adenomas and acromegaly. All but one patient had locally invasive macroadenomas, and in the majority of cases, there was parasellar growth. Radiosurgery was the initial treatment for seven patients. Fourteen patients were previously treated by pituitary surgery, eight of whom had undergone conventional external pituitary irradiation as well. All patients had clinical signs of active acromegaly before radiosurgery. The radiation doses given to the previously untreated patients or those who only underwent surgery were 40 to 70 Gy in each of one to three irradiations. The patients with previous external irradiation received a lower dose of 30 to 50 Gy in each of one or two irradiations. The patients were observed during a period of 1 to 21 years from the first radiosurgical session. Two young patients had a clinical remission with a substantial decline of GH levels to near normal serum profiles. Another eight patients obtained reduction of GH levels and clinical activity. More than half of the patients (11 of 21) had minor or no effects from the treatment. There were no complications from the radiosurgery except the development of pituitary insufficiency in 2 of 13 patients who did not undergo previous conventional external irradiation. The remission rates were lower than the results previously reported by us for radiosurgery for Cushing's disease. This may be a result of the predominance in the present study of invasive macroadenomas and single treatments and to the lower radiation doses used in the patients who underwent conventional irradiation previously.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Adenoma/cirurgia , Radioisótopos de Cobalto/uso terapêutico , Hormônio do Crescimento/biossíntese , Neoplasias Hipofisárias/cirurgia , Radiocirurgia , Acromegalia/etiologia , Adenoma/complicações , Adenoma/metabolismo , Adulto , Idoso , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Hipofisárias/complicações , Neoplasias Hipofisárias/metabolismo , Radiocirurgia/efeitos adversos , Radiocirurgia/instrumentação , Estudos Retrospectivos
17.
Neuroendocrinology ; 54(3): 196-201, 1991 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-1719442

RESUMO

Insulin-like growth factor (IGF)-II and its binding proteins were demonstrated to be present in human craniopharyngioma cyst fluid using gel filtration and ligand blot analyses. Immunoreactive IGF-II in 3 patients was found to be 274, 232 and 310 ng/ml after gel chromatography whereas IGF-I concentrations were 13, 8 and 15 ng/ml. The IGF-II levels were severalfold higher in cyst fluid than in spinal fluid while the IGF-I levels in both fluids did not differ significantly. The binding proteins showed high affinities for [125I]IGF-II which could be displaced by unlabelled IGF-II. With the ligand blot analysis, [125I]IGF-II shows bands at 300, 175 and 46/43 kilodaltons probably representing IGF-II receptor and IGFBP-3. IGFBP-1 levels 17, 22 and 45 ng/ml, respectively, were undetectable by ligand blot.


Assuntos
Proteínas de Transporte/análise , Craniofaringioma/química , Exsudatos e Transudatos/química , Fator de Crescimento Insulin-Like II/análise , Fator de Crescimento Insulin-Like I/análise , Neoplasias Hipofisárias/química , Adulto , Idoso , Criança , Humanos , Proteínas de Ligação a Fator de Crescimento Semelhante a Insulina
18.
Artigo em Inglês | MEDLINE | ID: mdl-1792977

RESUMO

Twenty-six cerebral metastatic tumours treated with the Gamma knife employing a large single dose were followed by repeated clinical and CT examinations. In most cases Gamma knife surgery was the only treatment. The follow up time has been longer than 6 months with a median follow up of 9 months. In all but one of the cases a remarkable progressive shrinkage of the tumour started 2-4 months after the therapy. The therapeutic results indicate that radiosurgery used even as the only form of treatment is the best treatment alternative for cerebral metastasis presently available.


Assuntos
Neoplasias Encefálicas/secundário , Neoplasias Encefálicas/cirurgia , Radiocirurgia/instrumentação , Técnicas Estereotáxicas/instrumentação , Idoso , Seguimentos , Humanos , Imageamento por Ressonância Magnética/instrumentação , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X/instrumentação
19.
Acta Neurochir (Wien) ; 99(3-4): 97-103, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2672706

RESUMO

Fourty-two consecutive patients with craniopharyngioma were treated by "stereotactic approach", i.e. preferentially stereotactic puncture and installation of colloid isotope into cystic tumours and external stereotactic single dose irradiation to solid tumour parts. In a minority of cases, such treatment was less suitable, and surgical removal and/or radiotherapy was used. There was no peroperative mortality. A long-term follow up (observation time 10-23 years) of the 31 patients alive indicated that they were socially well adapted with a high rate of fulltime work and a low rate of intercurrent disease. In spite of substitution therapy for pituitary insufficiency in most cases, the patients were subjectively seldom disturbed by their disease. Our results support a change in the choice of therapy for craniopharyngioma patients, from open neurosurgery to the less invasive stereotactic techniques.


Assuntos
Craniofaringioma/radioterapia , Testes de Função Hipofisária , Irradiação Hipofisária/métodos , Neoplasias Hipofisárias/radioterapia , Ajustamento Social , Técnicas Estereotáxicas , Adolescente , Adulto , Braquiterapia/métodos , Criança , Pré-Escolar , Avaliação da Deficiência , Feminino , Seguimentos , Humanos , Hipopituitarismo/psicologia , Masculino , Pessoa de Meia-Idade , Radioisótopos de Ítrio/uso terapêutico
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