Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 26
Filtrar
1.
Breast Cancer Res Treat ; 203(3): 477-486, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37923963

RESUMO

PURPOSE: In the treatment of breast cancer, neo-adjuvant chemotherapy is often used as systemic treatment followed by tumor excision. In this context, planning the operation with regard to excision margins relies on tumor size measured by MRI. The actual tumor size can be determined through pathologic evaluation. The aim of this study is to investigate the correlation and agreement between pre-operative MRI and postoperative pathological evaluation. METHODS: One hundred and ninety-three breast cancer patients that underwent neo-adjuvant chemotherapy and subsequent breast surgery were retrospectively included between January 2013 and July 2016. Preoperative tumor diameters determined with MRI were compared with postoperative tumor diameters determined by pathological analysis. Spearman correlation and Bland-Altman agreement methods were used. Results were subjected to subgroup analysis based on histological subtype (ER, HER2, ductal, lobular). RESULTS: The correlation between tumor size at MRI and pathology was 0.63 for the whole group, 0.39 for subtype ER + /HER2-, 0.51 for ER + /HER2 + , 0.63 for ER-/HER2 +, and 0.85 for ER-/HER2-. The mean difference and limits of agreement (LoA) between tumor size measured MRI vs. pathological assessment was 4.6 mm (LoA -27.0-36.3 mm, n = 195). Mean differences and LoA for subtype ER + /HER2- was 7.6 mm (LoA -31.3-46.5 mm, n = 100), for ER + /HER2 + 0.9 mm (LoA -8.5-10.2 mm, n = 33), for ER-/HER2+ -1.2 mm (LoA -5.1-7.5 mm, n = 21), and for ER-/HER- -0.4 mm (LoA -8.6-7.7 mm, n = 41). CONCLUSION: HER2 + and ER-/HER2- tumor subtypes showed clear correlation and agreement between preoperative MRI and postoperative pathological assessment of tumor size. This suggests that MRI evaluation could be a suitable predictor to guide the surgical approach. Conversely, correlation and agreement for ER + /HER2- and lobular tumors was poor, evidenced by a difference in tumor size of up to 5 cm. Hence, we demonstrate that histological tumor subtype should be taken into account when planning breast conserving surgery after NAC.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/cirurgia , Terapia Neoadjuvante/métodos , Estudos Retrospectivos , Receptor ErbB-2 , Imageamento por Ressonância Magnética/métodos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico
2.
Eur J Surg Oncol ; 48(8): 1692-1698, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35241322

RESUMO

INTRODUCTION: Breast surgery has become less invasive without compromising survival and aimed at improving quality of life (QoL) in terms of satisfaction with cosmesis. Despite that, short-term patient-perceived aesthetic results after breast-conserving surgery (BCS) can still be displeasing. Long-term analysis regarding contentment with cosmesis are lacking and could be different, considering that over time, patients' priorities might change and a different thought-out judgment could be given. The goal of this study is to describe long-term results in QoL after BCS and to identify possible predictors for disappointing aesthetic results. METHODS: In this retrospective cohort study, the long-term outcomes of QoL, patient-reported outcome measurements and aesthetic outcomes were investigated 4.5-10.8 years after BCS. In total, 104 patients received standardized questionnaires from the European Organisation of Research and Treatment of Cancer. The aesthetic results after BCS were evaluated subjectively through a diverse panel of healthcare observers. Objective assessment of the aesthetic results was done using the BCCT.core system of evaluating standardised breast photographs. Factors influencing aesthetic outcome were statistically analysed. RESULTS: QoL was high in around 75% of the patients. Correlation between QoL and aesthetic outcomes was found according to Spearman's correlation (r = 0.262, p = 0.007). Significant factors negatively influencing patient reported aesthetic outcomes were sentinel node procedure (p = 0.016), axillary lymph node dissection (p = 0.004), chemotherapy (p = 0.001), and hormonal therapy (p = 0.001). CONCLUSION: The majority of the patients have acceptable QoL after BCS during long-term follow-up. Unacceptable aesthetic outcomes after BCS are associated with lower QoL and are influenced by sentinel node procedure, axillary lymph node dissection, chemotherapy, and hormonal therapy.


Assuntos
Neoplasias da Mama , Mastectomia Segmentar , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Estética , Feminino , Humanos , Mastectomia Segmentar/métodos , Qualidade de Vida , Estudos Retrospectivos
3.
J Infect Dis ; 226(Suppl 1): S102-S109, 2022 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-34522947

RESUMO

BACKGROUND: In older adults, the burden of respiratory syncytial virus (RSV) resembles that of influenza and may even be considered worse due to the lack of preventive interventions. This study was performed to identify the available literature on RSV infection in older adults, and to provide updated exploratory results of the cost-effectiveness of a hypothetical RSV vaccine in the Netherlands and the United Kingdom. METHODS: A literature search was performed in Medline and EMBASE on 11 November 2019, which served as input for a static decision-tree model that was used to estimate the EJP, for an RSV vaccine applying different willingness-to-pay (WTP) thresholds. WTP thresholds applied were €20 000 and €50 000 per quality-adjusted life-year for the Netherlands, and £20 000 and £30 000 per quality-adjusted life-year for the United Kingdom. Analyses were-in line with country-specific guidelines-conducted from a societal perspective for the Netherlands and a third-party payer perspective for the United Kingdom. The robustness of the cost-effectiveness results was tested in sensitivity analysis. RESULTS: After screening the literature, 3 studies for the Netherlands and 6 for the United Kingdom remained to populate the country-specific models. In the base case analysis for the Netherlands (mean RSV incidence, 3.32%), justifiable vaccine prices of €16.38 and €50.03 were found, based on applying the lower and higher WTP thresholds, respectively. Similarly, for the United Kingdom (mean incidence, 7.13%), vaccine prices of £72.29 and £109.74 were found, respectively. CONCLUSION: RSV vaccination may well be cost-effective in both the Netherlands and the United Kingdom, depending on the exact RSV incidence, vaccine effectiveness and price. However, sensitivity analysis showed that the results were robust based on varying the different parameter estimates and assumptions. With RSV vaccines reaching the final stages of development, a strong need exists for cost-effectiveness studies to understand economically justifiable pricing of the vaccine.


Assuntos
Vacinas contra Vírus Sincicial Respiratório , Vírus Sincicial Respiratório Humano , Análise Custo-Benefício , Países Baixos/epidemiologia , Reino Unido/epidemiologia
4.
Vaccine ; 37(43): 6282-6284, 2019 10 08.
Artigo em Inglês | MEDLINE | ID: mdl-31515151

RESUMO

Recently, the Dutch Health Council advised on elderly pneumococcal vaccination favouring the conventional polysaccharide vaccine over the novel conjugated vaccine. This advice was strongly inspired by a cost-effectiveness analysis considered to show favourable outcomes for the polysaccharide but not for the conjugated vaccine. We argue that using the same data and methods as presented by the Health Council, a different perspective on the results leads to a conclusion that not only the polysaccharide but also the conjugated pneumococcal vaccine is cost-effective. Our alternative perspective concerns the use of realistic vaccine prices, and applying an adequate time horizon for cost-effectiveness modelling. Notably, for one-off vaccination of 65-years old elderly, in all investigated analyses, also the conjugated vaccine seems cost-effective; i.e. well below the threshold of €20,000 per quality-adjusted life year, reflecting the most stringent threshold used for vaccines in the Netherlands.


Assuntos
Análise Custo-Benefício , Infecções Pneumocócicas/prevenção & controle , Vacinas Pneumocócicas/economia , Vacinação/economia , Idoso , Idoso de 80 Anos ou mais , Feminino , Conselhos de Planejamento em Saúde , Humanos , Masculino , Países Baixos , Vacinas Pneumocócicas/administração & dosagem , Anos de Vida Ajustados por Qualidade de Vida , Vacinas Conjugadas/administração & dosagem , Vacinas Conjugadas/economia
5.
Int J Surg Case Rep ; 32: 58-61, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28249232

RESUMO

INTRODUCTION: Aortitis is a general term that refers to all conditions involving an inflammation of the aortic wall. This case report describes the surgical approach of a patient with infectious and symptomatic aortitis caused by the rare vector Prevotella intermedia. PRESENTATION OF CASE: A 44-year old male patient was admitted with fever and general discomfort after a period of sore throat in a non-teaching hospital. After two weeks he developed acute abdominal and back pain accompanied by sweating and elevated infection parameters. Computed tomography angiography revealed atherosclerotic changes of the infrarenal aorta with a locally contained rupture of the aorta alongside peri-aortal signs of inflammation (and aortitis aspects). An urgent aortic reconstruction was performed according to Nevelsteen. The blood cultures turned out positive for Prevotella intermedia. Postoperatively the patient received antibiotics for six weeks. The patient recovered uneventful from this infection and surgical procedure. DISCUSSION: A complicated and acute aortitis is a rare but potentially life-threatening disease. The aetiology can be ordered into two main groups; inflammatory and infectious. Diagnosis is based upon symptoms, biochemical values, microbiological results and imaging modalities. Treatment depends on aetiology and should be discussed in an experienced multidisciplinary setting. Infectious aortitis should be treated with antibiotics for at least six weeks with close monitoring of the patient's clinic and biochemical values, even after surgery. CONCLUSION: Prevotella intermedia is a rare causative agent for aortitis. Acute aortitis is a challenging clinical entity which should be managed in an equipped medical center by an experienced multidisciplinary team.

6.
Neth J Med ; 70(6): 272-7, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22859419

RESUMO

BACKGROUND: In this study we investigate the costs and benefits of topical mesalazine combined with oral mesalazine therapy for active ulcerative colitis (UC), and once daily (OD ) mesalazine 2 grams versus twice daily (BID ) for maintaining UC remission. METHODS: Two decision analytic models were constructed to evaluate treatment costs and quality-adjusted life years (QALYs) associated with mesalazine. The first model explored 4 g oral mesalazine in combination with 1 g topical mesalazine during active UC compared with 4 g oral mesalazine monotherapy for achieving clinical remission. The second model compared remission rates at one year for OD 2 g oral mesalazine compared with BID 1 g adjusted for compliance. All direct costs were obtained from established treatment costs in the Netherlands. RESULTS: The average cost of treatment to transition an active UC patient into remission using oral plus topical mesalazine or oral mesalazine monotherapy was v2207 (95% CI: v1402 to v3332) and v2945 (95% CI: v1717 to v4592), respectively. The annual average cost-saving of adding topical mesalazine delivered for four weeks during active UC was v738. The average annual costs of maintenance of remission with OD and BID therapy were v1293 (95% CI: v1062 to v1496) and v1502 (95% CI: v1262 to 1708), respectively with an annual average per person savings of v209. CONCLUSION: Topical mesalazine during acute UC flares results in lower costs due to reduced healthcare consumption attributed to faster symptom resolution. Furthermore, as a result of lower costs and modest QALY gains, maintenance therapy using OD mesalazine is the dominant treatment option if compared with BID mesalazine.


Assuntos
Colite Ulcerativa , Mesalamina , Administração Oral , Anti-Inflamatórios não Esteroides/uso terapêutico , Colite Ulcerativa/tratamento farmacológico , Humanos , Países Baixos
7.
Tijdschr Psychiatr ; 51(10): 773-7, 2009.
Artigo em Holandês | MEDLINE | ID: mdl-19821246

RESUMO

BACKGROUND: This article focuses on two patients with psychiatric symptoms arising from systemic lupus erythematosus (SLE). Affective and psychotic symptoms frequently occur in SLE, often in combination with cognitive disturbances, and can be a first manifestation of the disorder. The diagnosis and treatment of a possible case of neuropsychiatric SLE should preferably take place in a multidisciplinary setting.


Assuntos
Transtornos Cognitivos/diagnóstico , Lúpus Eritematoso Sistêmico/psicologia , Transtornos Mentais/diagnóstico , Adulto , Transtornos Cognitivos/etiologia , Feminino , Humanos , Lúpus Eritematoso Sistêmico/complicações , Transtornos Mentais/etiologia
8.
Aliment Pharmacol Ther ; 23(11): 1595-600, 2006 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-16696808

RESUMO

BACKGROUND: An increase of therapeutic substitution after patent expiry might have a negative effect on cost-savings generated with newly introduced generic drugs. To evaluate influences of patent expiry on therapeutic substitution, switch behaviour before and after patent expiry was investigated. AIM: To describe proton pump inhibitor use and investigate substitution patterns from omeprazole before and after patent expiry. METHODS: Data were obtained from the InterAction DataBase. Proportional proton-pump inhibitor use was identified per quarter during the study period 2000-2003. For the second part two cohorts--one before and one after patent expiry--were defined. The number of switchers was quarterly identified during 2-year follow-up period. For statistical analyses the chi-square test and hazard ratio were used. RESULTS: In proportional use, a downward trend for omeprazole was found. After patent expiry, significantly more patients switched to other proton pump inhibitors (P < 0.001). The hazard ratio of 0.62 (95% CI: 0.57-0.69), indicates that for every six patients switching before patent expiry, 10 patients switch after patent expiry. CONCLUSION: After patent expiry more patients switch to another proton pump inhibitor. In light of the total savings achieved with generic omeprazole, the importance of this negative impact on total cost-savings on proton pump inhibitors is unclear.


Assuntos
Omeprazol/economia , Bombas de Próton/economia , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Países Baixos/epidemiologia , Omeprazol/administração & dosagem , Inibidores da Bomba de Prótons
9.
Mol Endocrinol ; 14(5): 623-33, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10809227

RESUMO

Bone morphogenetic protein-4 (BMP-4) plays an important role in the onset of endochondral bone formation in humans, and a reduction in BMP-4 expression has been associated with a variety of bone diseases. Here we describe, by transient transfection assays in bone cells, that the human BMP-4 promoter recently characterized in our laboratory can be stimulated specifically by antiestrogens but not by estrogens or other steroid hormones. This activity is dependent on the presence of the estrogen receptor (ER)-alpha, although the promoter lacks a consensus estrogen-responsive element. No activity was observed in the presence of ERbeta, but synergy was observed when both ER subtypes were cotransfected. The observed stimulation of BMP-4 promoter activity by antiestrogens appeared bone cell specific and was reversed upon addition of estrogens. Since antiestrogens are known to be effective in hormone replacement therapies for postmenopausal women, this observation may help to develop new strategies for treatment and prevention of osteoporosis.


Assuntos
Proteínas Morfogenéticas Ósseas/genética , Moduladores de Receptor Estrogênico/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Osteoblastos/efeitos dos fármacos , Regiões Promotoras Genéticas/efeitos dos fármacos , Cloridrato de Raloxifeno/farmacologia , Adenocarcinoma/patologia , Sequência de Bases , Proteína Morfogenética Óssea 4 , Neoplasias Ósseas/patologia , Neoplasias da Mama/patologia , Células Cultivadas , Dimerização , Desenho de Fármacos , Neoplasias do Endométrio/patologia , Receptor alfa de Estrogênio , Receptor beta de Estrogênio , Estrogênios , Feminino , Humanos , Dados de Sequência Molecular , Neoplasias Hormônio-Dependentes/patologia , Especificidade de Órgãos , Osteoblastos/metabolismo , Osteogênese/genética , Osteoporose/prevenção & controle , Osteossarcoma/patologia , Pós-Menopausa , Receptores de Estrogênio/química , Receptores de Estrogênio/efeitos dos fármacos , Receptores de Estrogênio/genética , Receptores de Estrogênio/fisiologia , Proteínas Recombinantes de Fusão/fisiologia , Estimulação Química , Transfecção , Células Tumorais Cultivadas
10.
Curr Med Chem ; 7(5): 561-76, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10702625

RESUMO

Ever since the discovery of estradiol and the elucidation of its chemical structure, there has been a great deal of interest in its mechanism of action and its potential therapeutic value. It is now well established that estrogens have many different functions in many different cell-types. With respect to the potential use of estrogens as therapeutics, there is an interest in controlling reproductive function, bone metabolism, cardiovascular disease, as well as in the prevention of hot flushes, mood changes and Alzheimer s disease. For over a decade, it was believed that estrogens signal through a a single estrogen receptor, now referred to as ERalpha, which belongs to a family of ligand-activated transcription factors. More recently, however, a second estrogen receptor ERbeta was identified. The current review describes similarities as well as differences between these two distinct estrogen receptors. Both ERalpha and ERbeta bind 17beta-estradiol with high affinity and they bind to classical estrogen response elements in a similar if not identical fashion. However, there are also major differences between ERalpha and ERbeta for instance with respect to their tissue distribution, the phenotype of the corresponding knock-out mice and their transcriptional activities. It is anticipated that a better understanding of these two receptors will eventually lead to more selective ways of modulating physiological processes which are influenced by estrogens. For this purpose, the development of ERalpha and ERbeta specific ligands, both agonists as well as antagonists, will be of great importance.


Assuntos
Estrogênios/fisiologia , Receptores de Estrogênio/fisiologia , Animais , Receptor alfa de Estrogênio , Receptor beta de Estrogênio , Feminino , Humanos , Masculino , Receptores de Estrogênio/efeitos dos fármacos , Receptores de Estrogênio/genética
11.
Mol Cell Biol Res Commun ; 1(2): 117-24, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10356360

RESUMO

The role of homeobox genes in signaling of recombinant human bone morphogenetic protein-2 (rhBMP-2) was studied in osteoblast-like cells. Expression of several homeobox genes was decreased by rhBMP-2. The finding that this regulation of homeobox gene expression by rhBMP-2 was not dependent on protein synthesis suggests that homeobox proteins can act as direct intermediates in signal transduction of BMPs. Therefore, we studied the regulation of neural cell adhesion molecule (NCAM), which has previously been described as a target gene of both rhBMP-2 and homeobox proteins. We now show that in osteoblast-like cells, rhBMP-2 inhibits NCAM expression, while HOXC6 increases its expression, both acting via the same region of the promoter. As overexpression of HOXC6 could abolish effects of rhBMP-2 on NCAM promoter activity, these data show for the first time that members of the homeobox gene family may form direct functional intermediates in the signaling mechanism of the TGF-beta superfamily.


Assuntos
Proteínas Morfogenéticas Ósseas/fisiologia , Proteínas de Homeodomínio/fisiologia , Moléculas de Adesão de Célula Nervosa/metabolismo , Transdução de Sinais/genética , Fator de Crescimento Transformador beta , Animais , Southern Blotting , Proteína Morfogenética Óssea 2 , Proteínas Morfogenéticas Ósseas/genética , Proteínas Morfogenéticas Ósseas/metabolismo , Linhagem Celular , Ensaio de Imunoadsorção Enzimática , Regulação da Expressão Gênica no Desenvolvimento , Proteínas de Homeodomínio/metabolismo , Humanos , Camundongos , Osteoblastos , Regiões Promotoras Genéticas , RNA Mensageiro/análise , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais/fisiologia , Transfecção
12.
Biochem Biophys Res Commun ; 233(2): 365-9, 1997 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-9144540

RESUMO

Homeobox gene expression in osteoblast-like cells was investigated using the polymerase chain reaction (PCR). A total of 13 homeobox genes was detected in U-2 OS (human osteosarcoma) and MC3T3-E1 (mouse osteoblast) cells by sequencing cloned PCR products. Using specific primers, a different pattern of Hox gene expression was shown for the neuroblastoma cell line SK-N-SH relative to U-2 OS and MC3T3-E1. Additionally, we showed that expression of HOXC6 in U-2 OS and SK-N-SH was differentially regulated by rhBMP-2, TGF-beta and activin-A. This suggests that specific Hox genes may be target genes for TGF-beta superfamily members, and allows us to further understand the complex functions of these growth factors and how they relate to growth and development.


Assuntos
Neoplasias Ósseas/genética , Expressão Gênica , Genes Homeobox , Neuroblastoma/genética , Osteossarcoma/genética , Fator de Crescimento Transformador beta/farmacologia , Animais , Sequência de Bases , Expressão Gênica/efeitos dos fármacos , Humanos , Camundongos , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Células Tumorais Cultivadas
13.
Biochem Biophys Res Commun ; 219(3): 789-94, 1996 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-8645259

RESUMO

The structure of the human bone morphogenetic protein-4 (BMP-4) gene has been characterized from a genomic cosmid clone of about 38 kb. The transcriptional unit of the human BMP-4 gene is encoded by 5 exons and spans approximately 7 kb. The exon-intron organization of the human BMP-4 gene is similar to that of the mouse gene, with notable sequence differences in the 5' non-coding exons. The human BMP-4 gene has at least two functional promoters, which are used in a cell type specific manner. This observation is of fundamental relevance for understanding the specific role of BMP-4 in skeletal development and bone remodeling.


Assuntos
Regulação da Expressão Gênica , Biossíntese de Proteínas , Proteínas/genética , Transcrição Gênica , Animais , Sequência de Bases , Proteínas Morfogenéticas Ósseas , Clonagem Molecular , Cosmídeos , Primers do DNA , DNA Complementar , Éxons , Biblioteca Genômica , Substâncias de Crescimento/biossíntese , Substâncias de Crescimento/genética , Humanos , Íntrons , Camundongos , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , RNA Mensageiro/análise , RNA Mensageiro/biossíntese , Mapeamento por Restrição
15.
Neuroscience ; 62(4): 1003-20, 1994 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7845582

RESUMO

The release of the neurohormones oxytocin and vasopressin from the neural lobe into the circulation is regulated in a complex manner, which has only been partly elucidated. At the level of the neural lobe, regulation of release can occur by various endogenous compounds that act on specific receptors present on the nerve terminals themselves. In addition, release may be modulated by an alternative pathway in which the local glia cells, the pituicytes, are involved. It is especially the latter pathway that is discussed in detail in this commentary.


Assuntos
Comunicação Celular , Neuroglia/fisiologia , Neurônios/fisiologia , Ocitocina/metabolismo , Neuro-Hipófise/metabolismo , Vasopressinas/metabolismo , Animais , Endorfinas/fisiologia , Neuropeptídeos/fisiologia , Neuro-Hipófise/citologia , Ratos , Receptores de Neuropeptídeos/fisiologia
16.
J Neurosci Methods ; 51(2): 217-27, 1994 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8051952

RESUMO

Opioid receptors were localized at the cellular level, using either anti-opioid receptor antibodies or a biotinylated opioid ligand. In addition, a simple method was developed for selection of second antisera on their potencies to detect particular monoclonal antibodies (mAbs). Most anti-opioid receptor antibodies tested were not able to recognize the opioid receptor in frozen or fixed tissue sections, which was in contrast with their ability to recognize opioid receptors in isolated membrane fractions. However, one batch of anti-idiotypic mAbs gave a good immunocytochemical staining. Distribution of immunoreactivity suggested that these antibodies recognized more than one opioid receptor subtype. After very short fixation times, staining with a biotinylated kappa-selective ligand (DAKLIB) could be observed in the neural and intermediate lobe of pituitary. This binding could be displaced by non-biotinylated DAKLI. The pattern of DAKLIB staining in the neural lobe had the appearance of binding to both nerve fibres and astrocytes. The present results show successful staining of tissue sections with anti-idiotypic antibodies and with a biotinylated ligand. The specificity is discussed in the light of control experiments, pharmacological data and previous studies.


Assuntos
Química Encefálica , Técnicas Imunoenzimáticas , Proteínas do Tecido Nervoso/análise , Receptores Opioides/análise , Sequência de Aminoácidos , Animais , Anticorpos Anti-Idiotípicos/imunologia , Anticorpos Monoclonais/imunologia , Biotina , Imunoglobulina G/imunologia , Imunoglobulina M/imunologia , Masculino , Dados de Sequência Molecular , Peptídeos , Neuro-Hipófise/química , Neuro-Hipófise/ultraestrutura , Ratos , Ratos Wistar
17.
J Neuroendocrinol ; 6(1): 47-56, 1994 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8025568

RESUMO

Previous studies have suggested an involvement of enkephalins in regulation of oxytocin (OXT) and vasopressin (AVP) release, which seems to disagree with the very low affinities of Met- and Leu-enkephalin for the kappa opioid receptor. As opioid receptors in the neural lobe exclusively exist of kappa receptors, we studied the binding characteristics of larger pro-enkephalin derived peptides for opioid binding sites in the neural lobe by means of light microscopic receptor autoradiography. In addition, the pharmacological characteristics of opioid binding sites in the neural lobe were compared with those in other parts of the pituitary. In the neural as well as the intermediate lobe both high and low affinity 3H-bremazocine binding sites were present. Binding to these sites was completely displaceable by both naloxone and nor-binaltorphimine suggesting that these sites represent kappa opioid receptors. Also with regard to selectivity and affinity characteristics to other ligands, opioid binding sites in the neural and intermediate lobe were quite similar. In the anterior lobe a very low level of bremazocine binding was present, which could not be displaced by nor-binaltorphimine. Displacement studies with pro-enkephalin and pro-dynorphin derived peptides showed that both groups of peptides could bind to opioid binding sites in the neural and intermediate lobe. Especially the relatively large pro-dynorphin and pro-enkephalin derived peptides, such as dynorphin 1-17 and BAM22, appeared to be very potent ligands for these opioid binding sites and were much more potent than smaller fragments, such as dynorphin 1-8, and Met- and Leu-enkephalin. These results contradict the existence of a mismatch in the neural (and intermediate) lobe with regard to the local type of opioid peptides and receptors present.


Assuntos
Hipófise/metabolismo , Receptores Opioides/metabolismo , Sequência de Aminoácidos , Analgésicos/farmacocinética , Animais , Autorradiografia , Benzomorfanos/farmacocinética , Ligação Competitiva/efeitos dos fármacos , Densitometria , Encefalinas/farmacocinética , Ligantes , Masculino , Dados de Sequência Molecular , Naloxona/farmacologia , Naltrexona/análogos & derivados , Naltrexona/farmacocinética , Hipófise/citologia , Neuro-Hipófise/citologia , Neuro-Hipófise/metabolismo , Precursores de Proteínas/farmacocinética , Ratos , Ratos Wistar , Receptores Opioides/efeitos dos fármacos , Receptores Opioides kappa/efeitos dos fármacos , Receptores Opioides kappa/metabolismo
18.
J Neuroendocrinol ; 5(5): 583-90, 1993 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8680428

RESUMO

Opioid peptides are present in nerve terminals in the rat neural lobe where they partially coexist with vasopressin. Morphological findings suggest that these neuropeptides are released onto pituicytes, which is in agreement with a possible role for the pituicyte in oxytocin and vasopressin release from the neural lobe. Pituicytes in culture respond to vasopressin with a mobilization of calcium from intracellular stores. In the present study this vasopressin induced increase in intracellular free calcium levels was both delayed and decreased by pre-exposure to dynorphin 1-17, while dynorphin 1-17 by itself did not affect basal calcium levels. All effects of dynorphin 1-17 could be blocked with naloxone. The present results suggest that opioid receptors are present on pituicytes and are coupled to a second messenger pathway by which opioid peptides may inhibit inositol phosphate dependent calcium mobilization by other neuropeptides, such as vasopressin.


Assuntos
Astrócitos/metabolismo , Cálcio/metabolismo , Dinorfinas/farmacologia , Neuro-Hipófise/metabolismo , Vasopressinas/farmacologia , Animais , Animais Recém-Nascidos , Astrócitos/efeitos dos fármacos , Células Cultivadas , Feminino , Proteína Glial Fibrilar Ácida/metabolismo , Processamento de Imagem Assistida por Computador , Neuro-Hipófise/citologia , Ratos , Ratos Wistar
19.
J Comp Neurol ; 336(4): 555-70, 1993 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-8245225

RESUMO

Neuropeptide FF (F8Famide, FMRFamide-like, or morphine modulating peptide) immunoreactivity was localized by light and electron microscopy in the hypothalamo-neurohypophyseal system of Wistar and Brattleboro rats. In Wistar rats neuropeptide FF was present in part of the magnocellular neurones of the paraventricular and supraoptic nuclei in which it was coexpressed with vasopressin. Neuropeptide FF containing fibres were present in the paraventricular and the supraoptic nuclei, and in the central part of the neural lobe. At the electron microscopic level, neuropeptide FF containing nerve terminals in the neural lobe formed synaptoid contacts exclusively with pituicytes. No neuropeptide FF containing neurovascular contacts or contacts with other neuronal structures were observed. In contrast with Wistar rats, neuropeptide FF was almost completely absent in cell bodies of the paraventricular and supraoptic nuclei, and in fibres of the neural lobe in Brattleboro rats. Only a few solitary cells could be observed in these structures. The present results demonstrate that neuropeptide FF coexists with vasopressin within the hypothalamo-neurohypophyseal system. As we did not observe neuropeptide FF containing neurovascular contacts, neuropeptide FF containing nerve terminals probably have a local function within the neural lobe. Neuropeptide FF may be involved in the modulation of oxytocin and vasopressin release, with the pituicyte as an intermediate cell.


Assuntos
Sistema Hipotálamo-Hipofisário/metabolismo , Neuropeptídeos/metabolismo , Animais , Especificidade de Anticorpos , Arginina Vasopressina/deficiência , Arginina Vasopressina/imunologia , Arginina Vasopressina/metabolismo , Colchicina/farmacologia , Sistema Hipotálamo-Hipofisário/anatomia & histologia , Sistema Hipotálamo-Hipofisário/imunologia , Immunoblotting , Imuno-Histoquímica , Masculino , Microscopia Eletrônica , Terminações Nervosas/metabolismo , Fibras Nervosas/metabolismo , Neuropeptídeos/imunologia , Ratos , Ratos Brattleboro , Ratos Wistar
20.
Microb Pathog ; 15(3): 207-15, 1993 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8271920

RESUMO

A DNA fragment from Bordetella pertussis, encoding the fim2 fimbrial subunit gene with adjacent sequences, was used as a probe for the detection of homologous sequences in chromosomal DNA of Bordetella avium. A 1.8 kb Sa1I-PstI fragment from the genome of B. avium, which hybridized with the probe, was isolated and sequenced. No fimbrial subunit gene was located on the B. avium DNA fragment. Two regions could be distinguished in the sequence of the fragment. Region 1, which was 80% identical to the sequence upstream of the fim2 gene of B. pertussis and region 2, which had no identity with any known sequence. A 491 bp EagI DNA fragment (probe A) within region 1 and a 650 bp EagI DNA fragment (probe B) within region 2 were used as DNA probes on restriction endonuclease digests of chromosomal DNA from various bacterial species. This hybridization experiment showed that the region 2 sequence was specific for B. avium. A polymerase chain reaction (PCR) with specific primers within region 2 resulted in the amplification of a 500 bp DNA fragment with B. avium DNA only. This PCR is a useful method for the rapid detection of B. avium and appeared useful to discriminate B. avium from other Bordetella species and also from Alcaligenes faecalis.


Assuntos
Bordetella/isolamento & purificação , DNA Bacteriano/genética , Reação em Cadeia da Polimerase , Perus/microbiologia , Alcaligenes/genética , Animais , Sequência de Bases , Southern Blotting , Bordetella/classificação , Bordetella/genética , Infecções por Bordetella/diagnóstico , Infecções por Bordetella/veterinária , Primers do DNA , Sondas de DNA , Dados de Sequência Molecular , Doenças das Aves Domésticas/diagnóstico , Análise de Sequência de DNA , Homologia de Sequência do Ácido Nucleico
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA