Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 118
Filtrar
Mais filtros

País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Minerva Ginecol ; 63(5): 465-70, 2011 Oct.
Artigo em Italiano | MEDLINE | ID: mdl-21926955

RESUMO

Long-term users of tamoxifen (TMX) are at increased risk for developing endometrial cancer. Early diagnosis is mainly based on transvaginal scan (TVS) and hysteroscopy with endometrial biopsy. Nevertheless, TVS does not provide a definitive diagnosis in most cases, particularly due to its high false-positive rate. In addition TMX related changes, such as "pseudocistic" pattern, affect endoscopic evaluation of the endometrium and biopsy sampling (in particular blind procedures) frequently yields insufficient tissue for diagnosis. The cause of the high inadequacy rate of endometrial biopsies in women on TMX might be related to the increase in endometrial fibrous component. The present case emphasizes the main difficulties in surveillance and early diagnosis of endometrial pathologies in TMX users. Liquid-based endometrial cytology played a determinant role in the diagnostic pathway of this patient. We believe it could be used solely or in association with TVS leading to many advantages in the surveillance of women receiving TMX.


Assuntos
Adenocarcinoma/induzido quimicamente , Adenocarcinoma/patologia , Antineoplásicos Hormonais/efeitos adversos , Neoplasias da Mama/tratamento farmacológico , Citodiagnóstico , Neoplasias do Endométrio/induzido quimicamente , Neoplasias do Endométrio/patologia , Pós-Menopausa , Tamoxifeno/efeitos adversos , Adenocarcinoma/radioterapia , Adenocarcinoma/cirurgia , Idoso , Antineoplásicos Hormonais/administração & dosagem , Biópsia , Citodiagnóstico/métodos , Diagnóstico Diferencial , Detecção Precoce de Câncer , Neoplasias do Endométrio/radioterapia , Neoplasias do Endométrio/cirurgia , Feminino , Seguimentos , Humanos , Histerectomia , Histeroscopia/métodos , Mastectomia , Valor Preditivo dos Testes , Radioterapia Adjuvante , Medição de Risco , Fatores de Risco , Sensibilidade e Especificidade , Tamoxifeno/administração & dosagem , Resultado do Tratamento
2.
J Cell Biol ; 152(6): 1289-99, 2001 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-11257128

RESUMO

During development, neuregulin-1 promotes Schwann cell proliferation and survival; its role in later events of Schwann cell differentiation, including myelination, is poorly understood. Accordingly, we have examined the effects of neuregulin-1 on myelination in neuron-Schwann cell cocultures. Glial growth factor (GGF), a neuregulin-1 isoform, significantly inhibited myelination by preventing axonal segregation and ensheathment. Basal lamina formation was not affected. Treatment of established myelinated cultures with GGF resulted in striking demyelination that frequently began at the paranodes and progressed to the internode. Demyelination was dose dependent and accompanied by dedifferentiation of Schwann cells to a promyelinating stage, as evidenced by reexpression of the transcription factor suppressed cAMP-inducible POU; a significant proportion of cells with extensive demyelination also proliferated. Two other Schwann cell mitogens, fibroblast growth factor-2 and transforming growth factor-beta, inhibited myelination but did not cause demyelination, suggesting this effect is specific to the neuregulins. The neuregulin receptor proteins, erbB2 and erbB3, are expressed on ensheathing and myelinating Schwann cells and rapidly phosphorylated with GGF treatment. GGF treatment of myelinating cultures also induced phosphorylation of phosphatidylinositol 3-kinase, mitogen-activated protein kinase, and a 120-kD protein. These results suggest that neuronal mitogens, including the neuregulins, may inhibit myelination during development and that activation of mitogen signaling pathways may contribute to the initial demyelination and subsequent Schwann cell proliferation observed in various pathologic conditions.


Assuntos
Bainha de Mielina/fisiologia , Neuregulina-1/farmacologia , Neurônios/fisiologia , Células de Schwann/fisiologia , Animais , Diferenciação Celular/fisiologia , Células Cultivadas , Técnicas de Cocultura , Doenças Desmielinizantes , Relação Dose-Resposta a Droga , Fator 2 de Crescimento de Fibroblastos/metabolismo , Immunoblotting , Laminina/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Bainha de Mielina/efeitos dos fármacos , Bainha de Mielina/ultraestrutura , Neuregulina-1/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/ultraestrutura , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação , Ratos , Receptor ErbB-2/metabolismo , Receptor ErbB-3/metabolismo , Células de Schwann/efeitos dos fármacos , Células de Schwann/ultraestrutura , Transdução de Sinais
3.
Clin Exp Obstet Gynecol ; 36(2): 97-101, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19688951

RESUMO

PURPOSE OF INVESTIGATION: To assess the ability of detecting the number of uterine myomas by transvaginal ultrasonography (TVS) performed supporting the clinical examination of general gynecologists' office practice. METHODS: A retrospective comparison of the number of myomas revealed by preoperative in-office TVS and documented after laparotomic myomectomy was conducted in 110 consecutive premenopausal patients referred for surgery. RESULTS: The sensitivity of TVS in revealing the exact number of myomas was 59.4% in the whole series. In the subgroup of 88 patients with a preoperative diagnosis of three or fewer myomas TVS missed at least one myoma in 31 (35.2%) cases, achieving a 64.8% sensitivity. Among the 72 women diagnosed with one myoma at preoperative TVS, 19 (26.4%) resulted to have two or more myomas at the end of surgery, reaching a 73.6% sensitivity of TVS in revealing the exact number of myomas. CONCLUSIONS: In-office TVS reinforces the clinical diagnosis of uterine myomas but it often fails in the detection of their number, resulting in a poor preoperative characterization of patients. The fact that one myoma may be overlooked in one-third of patients theoretically eligible for laparoscopic conservative surgery may motivate the implementation of US diagnosis when laparoscopic myomectomy is considered.


Assuntos
Leiomioma/diagnóstico por imagem , Neoplasias Uterinas/diagnóstico por imagem , Adulto , Endossonografia/métodos , Feminino , Humanos , Laparoscopia , Leiomioma/cirurgia , Pessoa de Meia-Idade , Sistemas Automatizados de Assistência Junto ao Leito , Sensibilidade e Especificidade , Neoplasias Uterinas/cirurgia
4.
Neuron ; 16(3): 515-27, 1996 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8785049

RESUMO

Neurotrophin 3 (NT-3) can support the survival of some embryonic sympathetic neuroblasts before they become nerve growth factor dependent. We show that NT-3 is produced in vivo by nonneuronal cells neighboring embryonic sympathetic ganglia. NT-3 mRNA is produced by these nonneuronal cells in vitro and is up-regulated by platelet-derived growth factor, ciliary neurotrophic factor, and glial growth factor 2 (a neuregulin). Nonneuronal cell-conditioned medium promotes survival and induces TrkA expression in isolated sympathetic neuroblasts, and this activity is blocked by anti-NT-3 antibody. Neuroblasts also enhance NT-3 production by nonneural cells. Neuroblasts synthesize several forms of neuregulin, and antibodies to neuregulin attenuate the effect of the neuroblasts on the nonneuronal cells. These data suggest a reciprocal cell-cell interaction, in which neuroblast-derived neuregulins promote NT-3 production by neighboring nonneuronal cells, which in turn promotes neuroblast survival and further differentiation.


Assuntos
Sobrevivência Celular/efeitos dos fármacos , Fatores de Crescimento Neural/farmacologia , Sistema Nervoso Simpático/efeitos dos fármacos , Animais , Sequência de Bases , Diferenciação Celular , Células Cultivadas , Camundongos , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , RNA Mensageiro/metabolismo , Fatores de Tempo
5.
Neuron ; 17(2): 229-43, 1996 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8780647

RESUMO

We show that GGF/neuregulin is a mitogen for prooligodendrocytes (O4+/O1- cells), oligodendrocytes (O4+/O1+ cells), and type-2 astrocytes. Heregulin beta 1, another neuregulin isoform, is also mitogenic. The proliferative effect of glial growth factor (GGF) does not require, but is greatly potentiated by, serum factors. GGF also promotes the survival of pro-oligodendrocytes under serum-free conditions. High levels of GGF reversibly inhibit the differentiation and lineage commitment of oligodendrocyte progenitors and, in differentiated cultures, result in loss of O1 and myelin basic protein expression. All three erbB receptors are expressed by progenitors and are activated by GGF; the relative abundance of these receptors changes during differentiation. Finally, cortical neurons release a soluble mitogen for pro-oligodendrocytes that is specifically blocked by antibodies to GGF. These results implicate the neuregulins in the neuronal regulation of oligodendrocyte progenitor proliferation, survival, and differentiation.


Assuntos
Glicoproteínas/farmacologia , Fatores de Crescimento Neural/farmacologia , Oligodendroglia/citologia , Transdução de Sinais/efeitos dos fármacos , Animais , Diferenciação Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Linhagem da Célula/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas/citologia , Córtex Cerebral/citologia , Regulação da Expressão Gênica , Glicoproteínas/metabolismo , Mitógenos/farmacologia , Fatores de Crescimento Neural/metabolismo , Neurregulinas , Neurônios/metabolismo , Prosencéfalo/citologia , Ratos , Receptor ErbB-2 , Receptores de Fator de Crescimento Neural/genética , Proteínas Recombinantes/farmacologia , Solubilidade , Células-Tronco/citologia
6.
Int J Gynecol Cancer ; 18(2): 306-11, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-17624992

RESUMO

The proper management of endometrial polyps still represents a clinical ongoing challenge, especially when they are asymptomatic and occasionally discovered. The aim of this study was to evaluate liquid-based endometrial cytology to manage endometrial polyps in postmenopausal age by its ability to exclude hidden premalignant and malignant changes within polyps. Three hundred fifty-nine consecutive postmenopausal patients who underwent hysteroscopic diagnosis of endometrial polyp over a 3-year period and who were scheduled for surgical removal within the three subsequent months were retrospectively evaluated. Histologic results after resection during operative hysteroscopy or during hysterectomy were compared with liquid-based cytology and endometrial biopsy obtained at the time of diagnostic hysteroscopy. Eight of 359 patients (2.2%) had malignant or premalignant polyps interpreted as benign finding at hysteroscopy. Unsatisfactory samples were higher for endometrial biopsy compared to liquid-based cytology in the whole series and in the subgroup of low-risk asymptomatic patients (P < 0.001). Endometrial biopsy and liquid-based cytology revealed a sensitivity of 62% and 87.5%, respectively and a 100% specificity. Considering the subgroup of low-risk asymptomatic patients, liquid-based cytology disclosed all the five pathologic lesions with a 100% sensitivity and specificity. In conclusion, liquid-based cytology proved to be a useful tool to establish the nature of endometrial polyps in postmenopausal patients. Complete removal of the lesion should be offered to all symptomatic patients and those with established risk factors for endometrial cancer. Conversely, a wait and see attitude should be considered in case of asymptomatic low-risk polyps with typical appearance on hysteroscopy and negative liquid-based cytology.


Assuntos
Pólipos/patologia , Doenças Uterinas/patologia , Idoso , Idoso de 80 Anos ou mais , Biópsia , Citodiagnóstico , Feminino , Humanos , Histeroscopia , Pessoa de Meia-Idade , Pólipos/diagnóstico , Pólipos/cirurgia , Pós-Menopausa , Estudos Retrospectivos , Doenças Uterinas/diagnóstico , Doenças Uterinas/cirurgia
7.
Eur J Gynaecol Oncol ; 29(4): 378-82, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18714574

RESUMO

PURPOSE OF INVESTIGATION: To estimate the persistence rate of high-risk HPV DNA (HR-HPV DNA) in a population treated totally by laser CO2 conization for high-grade cervical intraepithelial neoplasia (HG-CIN), and to examine if this persistence might be considered an independent risk factor for relapsing disease. METHODS: All women with a histological diagnosis of HG-CIN and planned for laser CO2 conization from January 2003 to December 2004 were prospectively submitted to a HR-HPV test prior to surgery and at three and six months of follow-up. Women providing written informed consent with 24 months of follow-up were enrolled in the study group. A positive HPV test, involvement of resection margins, age at first intercourse, smoking habits, parity and age at conization > 50 years old were considered as risk factors for relapsing HG-CIN during follow-up, and were univariately and multivariately analyzed to discover any independent influencing factors. RESULTS: Of HG-CIN 15.4% resulted not to be HPV related nor relapsing. The HPV clearance rate after treatment was 78.8%. Involvement of resection margins and HR-HPV DNA persistence post-treatment resulted as the only two statistically significant risk factors for HG-CIN recurrence (rate 3.8%). HR-HPV DNA persistence in follow-up resulted to be independent from other risk factors at multivariate analysis. CONCLUSIONS: Although able to reach a low recurrence rate of HG-CIN, laser CO2 conization does not remove HPV infection completely from the cervix with a case of persistence in every five treated patients. In our experience this persistence in itself represents an independent risk factor for developing relapsing disease and constitutes the basis to introduce HPV testing even in the follow-up of patients treated for HG-CIN by laser CO2 conization.


Assuntos
Conização , Terapia a Laser/métodos , Recidiva Local de Neoplasia/patologia , Papillomaviridae/isolamento & purificação , Infecções por Papillomavirus/virologia , Displasia do Colo do Útero/patologia , Adulto , Colo do Útero/patologia , Colo do Útero/cirurgia , Colo do Útero/virologia , Estudos de Coortes , DNA Viral/análise , Feminino , Seguimentos , Humanos , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/virologia , Papillomaviridae/genética , Infecções por Papillomavirus/patologia , Prognóstico , Estudos Prospectivos , Estudos Retrospectivos , Fatores de Risco , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/cirurgia , Esfregaço Vaginal , Displasia do Colo do Útero/cirurgia , Displasia do Colo do Útero/virologia
8.
Skull Base ; 18(3): 213-6, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18978968

RESUMO

Intracranial enterogenous cysts are rare. There have been only two cases reported of such cysts that extended into both the infratentorial and supratentorial compartments. We add a third case and review the literature to assess their pathogenesis, clinical features, and management.

9.
Talanta ; 152: 378-91, 2016 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-26992534

RESUMO

This paper reports the first application of the silica based mesoporous material MCM-41 as a sorbent in solid phase extraction, to pre-concentrate pharmaceuticals of very different polarity (atenolol, nadolol, pindolol, timolol, bisoprolol, metoprolol, betaxolol, ketoprofen, naproxen, ibuprofen, diclofenac, tolfenamic acid, flufenamic acid and meclofenamic acid) in surface waters. The analytes were extracted from 100mL water samples at pH 2.0 (containing 10(-3) mol/L of sodium chloride) by passing the solution through a cartridge filled with 100 mg of MCM-41. Following elution, the pharmaceuticals were determined by micro-liquid chromatography and triple quadrupole-mass spectrometry. Two selected reaction monitoring transitions were monitored per compound, the most intense one being used for quantification and the second one for confirmation. Matrix effect was found in real waters for most analytes and was overcome using the standard addition method, which compared favorably with the matrix matched calibration method. The detection limits in solvent (acetonitrile:water 10:90, v/v) ranged from 0.01 to 1.48 µg/L and in real water extracts from 0.10 to 3.85 µg/L (0.001-0.0385 µg/L in the water samples). The quantitation limits in solvent were in the range 0.02-4.93 µg/L, whereas in real water extracts were between 0.45 and 10.00 µg/L (0.0045 and 0.1000 µg/L in the water samples). When ultrapure water samples were spiked at two concentration levels of each pharmaceutical (0.1 and 0.2 µg/L) and quantified using solvent based calibration graphs, recoveries were near 100%. However, recoveries for most pharmaceuticals were comparable or better than de described above, when river water samples (spiked at the same concentration levels) were quantified by the standard addition method and slightly worse using the matrix matched calibration method. Five real samples (two rivers, one dam and two fountain water samples) were analyzed by the developed method, atenolol, timolol, betaxolol, nadolol and diclofenac being found in some of them, at levels higher than their quantitation limits.


Assuntos
Cromatografia Líquida/métodos , Espectrometria de Massas/métodos , Preparações Farmacêuticas/análise , Preparações Farmacêuticas/isolamento & purificação , Dióxido de Silício/química , Extração em Fase Sólida/métodos , Água/química , Limite de Detecção , Preparações Farmacêuticas/química , Porosidade , Rios/química , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/química , Poluentes Químicos da Água/isolamento & purificação
10.
Oncogene ; 11(2): 325-35, 1995 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-7624147

RESUMO

Schwann cells are thought to be abnormal in type 1 neurofibromatosis (NF1) and to contribute to the formation of benign and malignant tumors in this disease. To test the role of the NF1 gene product neurofibromin as a Ras-GTPase activating protein in Schwann cells, and to study the effect of the loss of neurofibromin on Schwann cell proliferation, we isolated Schwann cells from mice with targeted disruption of NF1. The properties of these neurofibromin deficient cells were strikingly similar to those of v-ras expressing rat Schwann cells with normal levels of neurofibromin. The similarities included: growth inhibition, noted as a decrease in cell division in response to glial growth factor 2 (GGF2) and of neuronal contact; morphological changes such as the appearance of elaborated processes; and elevated levels of Ras-GTP. Furthermore, Ras-GTP levels in the neurofibromin deficient Schwann cells were consistently elevated in response to GGF2 treatment. In contrast to these results, introduction of v-ras into a Schwannoma cell line (RN22) led to cell transformation. We conclude that neurofibromin functions as a major regulator of Ras-GTP in Schwann cells; however, mutation in NF1 by itself is unlikely to explain the hyperplasia observed in Schwann cell tumors in NF1 disease.


Assuntos
Genes ras , Proteínas do Tecido Nervoso/deficiência , Proteína Oncogênica p21(ras)/metabolismo , Proteínas/genética , Células de Schwann/citologia , Células de Schwann/fisiologia , Animais , Divisão Celular/efeitos dos fármacos , Divisão Celular/fisiologia , Embrião de Mamíferos/fisiologia , Feminino , GTP Fosfo-Hidrolases/análise , GTP Fosfo-Hidrolases/metabolismo , Gânglios Espinais/citologia , Gânglios Espinais/embriologia , Regulação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Substâncias de Crescimento/farmacologia , Camundongos , Camundongos Transgênicos , Neurofibromina 1 , Neurônios/fisiologia , Proteína Oncogênica p21(ras)/genética , Gravidez , Ratos , Células de Schwann/efeitos dos fármacos , Transformação Genética
11.
Oncogene ; 17(17): 2195-209, 1998 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-9811451

RESUMO

Schwannomas are peripheral nerve tumors that typically have mutations in the NF2 tumor suppressor gene. We compared cultured schwannoma cells with Schwann cells from normal human peripheral nerves (NHSC). Both cell types expressed specific antigenic markers, interacted with neurons, and proliferated in response to glial growth factor, confirming their identity as Schwann cells. Schwannoma cells frequently had elevated basal proliferation compared to NHSC. Schwannoma cells also showed spread areas 5-7-fold greater than NHSC, aberrant membrane ruffling and numerous, frequently disorganized stress fibers. Dominant negative Rac inhibited schwannoma cell ruffling but had no apparent effect on NHSC. Schwannoma cell stress fibers were inhibited by C3 transferase, tyrphostin A25, or dominant negative RhoA. These data suggest that the Rho and Rac pathways are abnormally activated in schwannoma cells. Levels of ezrin and moesin, proteins related to the NF2 gene product, merlin, were unchanged in schwannoma cells compared to NHSC. Our findings demonstrate for the first time that cell proliferation and actin organization are aberrant in schwannoma cells. Because NF2 is mutant in most or all human schwannomas, we postulate that loss of NF2 contributes to the cell growth and cytoskeletal dysfunction reported here.


Assuntos
Proteínas de Membrana/metabolismo , Neurilemoma/patologia , Proteínas S100 , Células de Schwann/patologia , Adulto , Idoso , Biomarcadores , Proteínas de Ligação ao Cálcio/metabolismo , Comunicação Celular , Divisão Celular , Membrana Celular/ultraestrutura , Tamanho Celular , Sobrevivência Celular , Células Cultivadas , Citoesqueleto/ultraestrutura , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Crescimento Neural/metabolismo , Neurilemoma/metabolismo , Neurilemoma/ultraestrutura , Neurofibroma/patologia , Neurofibromina 2 , Subunidade beta da Proteína Ligante de Cálcio S100 , Células de Schwann/metabolismo , Células de Schwann/ultraestrutura , Transdução de Sinais
12.
J Neurosci ; 21(13): 4740-51, 2001 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-11425901

RESUMO

Neuregulin 1 (Nrg-1) isoforms have been shown to influence the emergence and growth of oligodendrocytes, the CNS myelin-forming cells. We have investigated how Nrg-1 signaling of ErbB receptors specifically controls the early stages of oligodendrocyte generation from multipotential neural precursors (NPs). We show here that embryonic striatal NPs express multiple Nrg-1 transcripts and proteins as well as their specific receptors, ErbB2 and ErbB4, but not ErbB3. The major isoform synthesized by striatal NPs is a transmembrane type III isoform called cysteine-rich domain Nrg-1. To examine the biological effect of Nrg-1, we added soluble ErbB3 (sErbB3) to growing neurospheres. This inhibitor of Nrg-1 bioactivity decreased mitosis of NPs and increased their apoptosis, resulting in a significant reduction in neurosphere size and number. When NPs were induced to migrate and differentiate by adhesion of neurospheres to the substratum, the level of type III isoforms detected by RT-PCR and Western blot decreased in parallel with a reduction in Nrg-1 fluorescence intensity in differentiating astrocytes, neurons, and oligodendrocytes. Pretreatment of growing neurospheres with sErbB3 induced a threefold increase in the proportion of oligodendrocytes generated from NPs migrating out of the neurosphere. This effect was not observed with an unrelated soluble receptor. Addition of sErbB3 during NP growth and differentiation enhanced oligodendrocyte maturation as shown by expression of galactocerebroside and myelin basic protein. We propose that both type III Nrg-1 signaling and soluble ErbB receptors modulate oligodendrocyte development from NPs.


Assuntos
Neuregulina-1/metabolismo , Neurônios/metabolismo , Oligodendroglia/metabolismo , Transdução de Sinais/fisiologia , Células-Tronco/metabolismo , Animais , Apoptose , Astrócitos/citologia , Astrócitos/metabolismo , Adesão Celular/fisiologia , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/fisiologia , Divisão Celular/efeitos dos fármacos , Divisão Celular/fisiologia , Movimento Celular/fisiologia , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Cromonas , Corpo Estriado/citologia , Corpo Estriado/embriologia , Corpo Estriado/metabolismo , Receptores ErbB/metabolismo , Glicosídeos , Camundongos , Camundongos Endogâmicos C57BL , Mitose/efeitos dos fármacos , Neuregulina-1/antagonistas & inibidores , Neuregulina-1/farmacologia , Neurônios/citologia , Oligodendroglia/citologia , Isoformas de Proteínas/antagonistas & inibidores , Isoformas de Proteínas/metabolismo , Isoformas de Proteínas/farmacologia , Ratos , Receptor ErbB-2/metabolismo , Receptor ErbB-3/metabolismo , Receptor ErbB-4 , Medula Espinal/citologia , Medula Espinal/embriologia , Medula Espinal/metabolismo , Células-Tronco/citologia , Células-Tronco/efeitos dos fármacos
13.
Circulation ; 100(4): 407-12, 1999 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-10421602

RESUMO

BACKGROUND: Neuregulins are a family of peptide growth factors that promote cell growth and viability. The potential role of neuregulin-erbB signaling in hypertrophic growth and later failure in the adult heart in vivo is not known. METHODS AND RESULTS: We used ribonuclease protection assays to quantify mRNA levels of neuregulin, erbB2, and erbB4 in left ventricular (LV) tissue and myocytes of normal rats and rats with aortic stenosis with pressure-overload hypertrophy 6 and 22 weeks after banding. At both stages of hypertrophy, Northern blot analyses of mRNA from LV myocytes showed upregulation of atrial natriuretic peptide, a molecular marker of hypertrophy (P<0.05). LV tissue neuregulin message levels were similar in animals with aortic stenosis compared with controls (P=NS) and were not detectable in myocytes. LV erbB2 and erbB4 message levels in LV tissue and myocytes were maintained during early compensatory hypertrophy in 6-week aortic stenosis animals compared with age-matched controls; in contrast, erbB2 and erbB4 message levels were depressed in 22-week aortic stenosis animals at the stage of early failure (both P<0.01 vs age-matched controls). Immunoblotting of erbB2 and erbB4 also showed normal protein levels in 6-week aortic stenosis animals compared with controls; however, erbB2 and erbB4 protein levels were depressed in 22-week aortic stenosis animals (48% decrease in erbB2, P<0.05, and 43% decrease in erbB4, P<0.01) relative to age-matched controls. CONCLUSIONS: The neuregulin receptors erbB2 and erbB4 are downregulated at both the message and protein levels at the stage of early failure in animals with chronic hypertrophy secondary to aortic stenosis. These data suggest a role for disabled erbB receptor signaling in the transition from compensatory hypertrophy to failure.


Assuntos
Estenose da Valva Aórtica/complicações , Receptores ErbB/metabolismo , Glicoproteínas/metabolismo , Hipertrofia Ventricular Esquerda/etiologia , Hipertrofia Ventricular Esquerda/metabolismo , Receptor ErbB-2/metabolismo , Animais , Estenose da Valva Aórtica/metabolismo , Receptores ErbB/genética , Glicoproteínas/genética , Hemodinâmica/fisiologia , Hipertrofia Ventricular Esquerda/fisiopatologia , Hibridização In Situ , Masculino , Miocárdio/metabolismo , Neurregulinas , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar , Receptor ErbB-2/genética , Receptor ErbB-4
14.
Chir Organi Mov ; 90(3): 229-40, 2005.
Artigo em Inglês, Italiano | MEDLINE | ID: mdl-16681101

RESUMO

The purpose of this study is to define, analyse and discuss the incidence and severity of the complications associated with anterior cervical spine surgery for degenerative disc diseases. The results and the management of complications of anterior spine surgery are discussed in relation to numerous previous published reports: precise knowledge of all potential accidents and pitfalls related to the surgical approaches and of their aetiology may contribute to preventing failures. The most common complication was a recurrent laryngeal nerve injury that developed in 7.9% of the cases. Dysphagia occurred in 5.6%, hoarseness in 5.2%, transient sore throat in 4.8%, worsening of pre-existing myelopathy in 3%, graft extrusion in 1.7%; root injury, haematoma, and wound infection developed in 0.87%. There was one case of oesophageal injury (0.43%) and there were no deaths related to the surgical approach. The rate of complications in our series has been reduced in the past years by 1) better patients selection: all of the patients in fact had previously received conservative treatment for at least four weeks; 2) more care in correct positioning of the patient during the operation; 3) meticolous removal of all harmful structures.


Assuntos
Vértebras Cervicais/cirurgia , Deslocamento do Disco Intervertebral/cirurgia , Disco Intervertebral/cirurgia , Complicações Pós-Operatórias , Doenças da Coluna Vertebral/cirurgia , Adulto , Idoso , Vértebras Cervicais/diagnóstico por imagem , Transtornos de Deglutição/etiologia , Esôfago/lesões , Feminino , Hematoma/etiologia , Rouquidão/etiologia , Humanos , Disco Intervertebral/diagnóstico por imagem , Deslocamento do Disco Intervertebral/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Faringite/etiologia , Traumatismos do Nervo Laríngeo Recorrente , Estudos Retrospectivos , Doenças da Coluna Vertebral/diagnóstico por imagem , Fusão Vertebral , Infecção da Ferida Cirúrgica/etiologia , Tomografia Computadorizada por Raios X
15.
J Comp Neurol ; 349(3): 389-400, 1994 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-7852632

RESUMO

The distribution of neuregulin transcripts in rat brains was studied by both RNA blotting and in situ hybridization. Our data demonstrate that multiple neuregulin transcripts are expressed in neurons of the basal forebrain, the hippocampus, the diencephalon, the cerebellum, the brainstem, and the spinal cord. Developmental changes in the distribution of neuregulin transcripts were observed only in the cerebellum and the hippocampus. The intense neuregulin hybridization signals in the brainstem motor and sensory nuclei and the spinal motor neurons are suggestive of a functional involvement of neuregulins in motor and sensory systems. The expression of neuregulins in other parts of the brain also indicates that these factors are involved in a variety of central nervous system functions.


Assuntos
Encéfalo/metabolismo , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Glicoproteínas/genética , Proteínas do Tecido Nervoso/genética , RNA Mensageiro/biossíntese , Animais , Encéfalo/crescimento & desenvolvimento , Hibridização In Situ , Neurregulinas , Ratos , Medula Espinal/crescimento & desenvolvimento , Medula Espinal/metabolismo
16.
J Neuroimmunol ; 100(1-2): 233-42, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10695733

RESUMO

Human white matter from non-neurologic cases, multiple sclerosis (MS) and other neurologic diseases (OND, inflammatory and non-inflammatory), was subjected to immunocytochemistry and Western blotting for expression of the neuregulin, glial growth factor-2 (GGF2), and its receptors, erbB2, erbB3 and erbB4. GGF2 has previously been shown to have mitogenic effects upon oligodendrocytes in vitro and an enhancing effect upon remyelination in animals with autoimmune demyelination. In all types of human white matter examined, expression of the ligand GGF2 and its three receptors was consistently found on oligodendrocytes, with higher levels being seen in cases of MS. Expression was also seen, albeit at lower levels, on astrocytes and microglial cells, the latter most commonly in MS and OND. In human lymph node tissue, some lymphocytes were positive for erbB2, erbB3 and erbB4. Western blots confirmed the presence of all three receptors in normal, MS and OND white matter. GGF2 and erbB receptor expression did not correlate with areas of remyelination and reactivity occurred throughout the tissue, with some increase in intensity at the edge of MS lesions. Examination of precursor oligodendrocyte immunoreactivity (with anti-PDGF-Ralpha and NG2), revealed widespread expression throughout both normal and diseased white matter. The presence of GGF2 and its receptors on oligodendrocytes and lymphocytes render this cell type a candidate for functional signaling via this pathway, perhaps in relationship to myelinating activity.


Assuntos
Encefalopatias/metabolismo , Neurregulinas/biossíntese , Receptor ErbB-2/biossíntese , Receptor ErbB-3/biossíntese , Western Blotting , Encéfalo/metabolismo , Receptores ErbB/biossíntese , Humanos , Imuno-Histoquímica , Linfonodos/metabolismo , Esclerose Múltipla/metabolismo , Receptor ErbB-4
17.
Cancer Lett ; 172(2): 133-5, 2001 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-11566487

RESUMO

Acetowhitening of the vulva has been related to a subclinical human papillomavirus (HPV) infection. No consense has been reached about undertaking -or not- any therapy for these acetowhite changes. We have observed from our clinical experience and in a 10 years observational follow-up, that acetowhitening of the vulva regarding high risk (16-18) and low risk (6-11) HPV groups (as assessed by PCR analysis) significantly decreased; and acetowhitening areas negative to polymerase chain reaction (PCR), significantly increased from 53% (202/382) to 85% (276/325) (P<0.001). Our findings suggest that independently from HPV type and in the absence of cofactors, there is a statistically significant spontaneous remission of these areas.


Assuntos
DNA Viral/análise , Papillomaviridae/isolamento & purificação , Vulva/patologia , Vulva/virologia , Adulto , Colposcopia , Anticoncepção , Feminino , Seguimentos , Humanos , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Prognóstico , Estudos Prospectivos , Fatores de Risco
18.
Cancer Lett ; 150(1): 71-8, 2000 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-10755389

RESUMO

We studied the effects of luteinising hormone-releasing hormone (LHRH) agonist leuproreline (1 microM for 96 h) and LHRH antagonist cetrorelix on the cell growth of primary cultures from nine human endometrial cancers using the sulphorhodamine colorimetric test. Histological examinations and reverse transcription and polymerase chain reaction amplification (RT-PCR) for LHRH receptors were also performed. The endometrial cancers examined had a medium to high degree of proliferative activity and a low degree of apoptotic power; furthermore, they expressed the LHRH receptor RNA variably, detectable in 71% of cases. The addition of leuproreline or cetrorelix to cell cultures inhibited growth in a statistically significant way compared to untreated control cells; nevertheless, the percentage of cell growth inhibition obtained was very variable. These data suggest that LHRH analogues can exert differential inhibitory effects on the growth of endometrial cancer, which seems to be independent of the expression of specific LHRH receptors.


Assuntos
Neoplasias do Endométrio/prevenção & controle , Hormônio Liberador de Gonadotropina/farmacologia , Idoso , Divisão Celular/efeitos dos fármacos , Neoplasias do Endométrio/genética , Neoplasias do Endométrio/patologia , Feminino , Hormônio Liberador de Gonadotropina/análogos & derivados , Humanos , Leuprolida/farmacologia , Pessoa de Meia-Idade , Pós-Menopausa , RNA Mensageiro/genética , Receptores LHRH/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Tumorais Cultivadas
19.
Neuroreport ; 10(3): 535-40, 1999 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-10208585

RESUMO

The loss of O-2A progenitor cells has been implicated as a critical event in radiation-induced spinal cord demyelination. To investigate whether glial growth factor 2 (GGF2) affects the number of O-2A cells in the irradiated rat cervical spinal cord, an ex vivo gene therapy approach was applied in which CHO cells engineered to express recombinant human GGF2 were injected into the cisterna magna of adult rats. Spinal cord irradiation reduced the number of O-2A cells in a dose-dependent manner. However, this radiation-induced decrease in O-2A progenitor cells was significantly attenuated by the delivery of GGF2 after irradiation. These data indicate that the cell-mediated delivery of GGF2 can reduce the loss of O-2A progenitors after irradiation.


Assuntos
Proteínas do Tecido Nervoso/metabolismo , Neurônios/metabolismo , Neurônios/transplante , Medula Espinal/patologia , Medula Espinal/efeitos da radiação , Células-Tronco/patologia , Células-Tronco/efeitos da radiação , Animais , Células CHO , Contagem de Células , Cisterna Magna/fisiologia , Cricetinae , Feminino , Engenharia Genética , Fator de Maturação da Glia , Humanos , Injeções , Pescoço , Ratos , Ratos Sprague-Dawley , Proteínas Recombinantes , Medula Espinal/metabolismo
20.
Eur J Obstet Gynecol Reprod Biol ; 104(1): 73-5, 2002 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-12128268

RESUMO

We report the case of a young woman taking a low-dose oral contraceptive (gestodene 0.075mg and ethinylestradiol 0.02mg) in whom we documented by both hormonal assays and sonographic evaluations the occurrence of ovulation, oocyte fertilization and embryo implantation. However, the implantation process did not complete and only a biochemical pregnancy was registered. On the basis of known actions of estroprogestin on endometrium that are not conducive to implantation, it is possible that the pregnancy loss was originated by oral contraceptive's hormonal influence at endometrial level.


Assuntos
Anticoncepcionais Orais/efeitos adversos , Implantação do Embrião/efeitos dos fármacos , Aborto Espontâneo , Adulto , Gonadotropina Coriônica Humana Subunidade beta/sangue , Endométrio/diagnóstico por imagem , Etinilestradiol/efeitos adversos , Feminino , Humanos , Norpregnenos/efeitos adversos , Ovulação , Gravidez , Ultrassonografia
SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa