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1.
Analyst ; 144(4): 1115-1127, 2019 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-30702730

RESUMO

Fourier transform infrared (FTIR) spectra of biological cells can reveal clinically important information about cells' composition, including their normal or cancerous status. The recently emerged diagnostic technique of spectral cytopathology (SCP) combines FTIR with multivariate statistical analysis to detect cell abnormalities, differentiate between cell types, and monitor disease progression. We demonstrate a new variant of SCP, a metasurface-enhanced infrared reflection spectroscopic cytopathology (MEIRSC) that utilises judiciously designed plasmonic metasurfaces to localize and enhance the evanescent field near the cell's membrane, and to carry out spectroscopic interrogations of the cells attached to the metasurface using reflected infrared light. Our findings indicate that the MEIRSC approach enables us to differentiate between normal and cancerous human colon cells. The sensitivity of MEIRSC is such that a very small (about 50 nm deep) portion of the cell can yield valuable diagnostic information.


Assuntos
Colo/citologia , Colo/patologia , Neoplasias do Colo/patologia , Espectrofotometria Infravermelho/métodos , Linhagem Celular Tumoral , Humanos , Microscopia , Análise de Componente Principal
2.
Transplant Proc ; 48(4): 1285-7, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27320605

RESUMO

The inhibitory function of HLA-G1, a class Ib molecule, on monocyte/macrophage-mediated cytotoxicity was examined. The expression of inhibitory receptors that interact with HLA-G, immunoglobulin-like transcript 2 (ILT2), ILT4, and KIR2DL4 (CD158d) on in vitro-generated macrophages obtained from peripheral blood mononuclear cells and the phorbol 12-myristate 13-acetate (PMA)-activated THP-1 cells were examined by flow cytometry. cDNAs of HLA-G1, HLA-G3, HLA-E, and human ß2-microglobulin were prepared, transfected into pig endothelial cells (PECs), and macrophage- and the THP-1 cell-mediated PEC cytolysis was then assessed. In vitro-generated macrophages expressed not only ILT2 and ILT4 but CD158d as well. The transgenic HLA-G1 on PEC indicated a significant suppression in macrophage-mediated cytotoxicity, which was equivalent to that of transgenic HLA-E. HLA-G1 was clearly expressed on the cell surface of PEC, whereas the levels of HLA-G3 were much lower and remained in the intracellular space. On the other hand, the PMA-activated THP-1 cell was less expressed these inhibitory molecules than in vitro-generated macrophages. Therefore, the HLA-G1 on PECs showed a significant but relatively smaller suppression to THP-1 cell-mediated cytotoxicity compared to in vitro-generated macrophages. These results indicate that by generating HLA-G1, but not HLA-G3, transgenic pigs can protect porcine grafts from monocyte/macrophage-mediated cytotoxicity.


Assuntos
Antígenos HLA-G/fisiologia , Leucócitos Mononucleares/imunologia , Macrófagos/imunologia , Animais , Animais Geneticamente Modificados , Antígenos CD/metabolismo , Citocinas/metabolismo , Citotoxicidade Imunológica/fisiologia , Células Endoteliais/imunologia , Endotélio/imunologia , Citometria de Fluxo , Antígenos HLA-G/metabolismo , Humanos , Células Matadoras Naturais/imunologia , Receptor B1 de Leucócitos Semelhante a Imunoglobulina , Glicoproteínas de Membrana/metabolismo , Receptores Imunológicos/metabolismo , Receptores KIR2DL4/metabolismo , Suínos , Transfecção/métodos
3.
Neurophysiol Clin ; 43(5-6): 267-87, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24314754

RESUMO

OBJECTIVE: The objective of this study is to specify, by reference to the normal newborn, the current contribution of the electroencephalogram (EEG) to the diagnosis and prognosis of hypoxic-ischemic encephalopathy (HIE) in the full-term newborn. Both digitized traditional EEG and cerebral function monitoring will be considered. DISCUSSION: A good knowledge of the EEG features of the sleep-wake cycle (SWC) is a prerequisite. We first describe the main features of normal and pathological EEGs. Very early recordings (before 6hours of life) are needed to indicate any required neuroprotective (hypothermia) and other (sedation, anticonvulsivants) treatments. CONCLUSIONS: Between the normal or near-normal tracings, which are associated with a good prognosis, and the very pathological ones (inactive, paroxysmal), which are associated with a poor vital or neurological prognosis, the interpretation of "intermediate" tracings--mainly represented by other types of discontinuous tracings--must take into account characteristics such as bursts and discontinuities, postnatal age, evolution of successive tracings, and treatments.


Assuntos
Encéfalo/fisiologia , Encéfalo/fisiopatologia , Eletroencefalografia , Hipóxia-Isquemia Encefálica/diagnóstico , Fases do Sono/fisiologia , Humanos , Hipóxia-Isquemia Encefálica/fisiopatologia , Recém-Nascido , Prognóstico
4.
Neurophysiol Clin ; 40(2): 59-124, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20510792

RESUMO

Following the pioneering work of C. Dreyfus-Brisac and N. Monod, research into neonatal electroencephalography (EEG) has developed tremendously in France. French neurophysiologists who had been trained in Paris (France) collaborated on a joint project on the introduction, development, and currently available neonatal EEG recording techniques. They assessed the analytical criteria for the different maturational stages and standardized neonatal EEG terminology on the basis of the large amount of data available in the French and the English literature. The results of their work were presented in 1999. Since the first edition, technology has moved towards the widespread use of digitized recordings. Although the data obtained with analog recordings can be applied to digitized EEG tracings, the present edition, including new published data, is illustrated with digitized recordings. Herein, the reader can find a comprehensive description of EEG features and neonatal behavioural states at different gestational ages, and also a definition of the main aspects and patterns of both pathological and normal EEGs, presented in glossary form. In both sections, numerous illustrations have been provided. This precise neonatal EEG terminology should improve homogeneity in the analysis of neonatal EEG recordings, and facilitate the setting up of multicentric studies on certain aspects of normal EEG recordings and various pathological patterns.


Assuntos
Encéfalo/crescimento & desenvolvimento , Eletroencefalografia , Recém-Nascido Prematuro/fisiologia , Artefatos , Encéfalo/fisiologia , Eletrocardiografia , Eletroencefalografia/métodos , Eletroencefalografia/normas , Eletromiografia , Epilepsia/congênito , Epilepsia/fisiopatologia , Feminino , Idade Gestacional , Humanos , Lactente , Comportamento do Lactente , Recém-Nascido , Movimento/fisiologia , Gravidez , Valores de Referência , Sono/fisiologia , Terminologia como Assunto , Vigília/fisiologia
6.
Kidney Int ; 73(9): 1038-47, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18288100

RESUMO

Mutations in the NPHS2 gene, encoding podocin, are responsible for familial autosomal recessive and sporadic cases of steroid-resistant nephrotic syndrome. We have successfully generated a mouse model in which the common p.R138Q mutation found in nephrotic patients is expressed in the kidney. Homozygous mice express the mutant protein, which is mislocated to the cytoplasm, along with a portion of the nephrin pool. These mice die within the first month of life, but their survival depends on the genetic background. Albuminuria manifests early and leads to progressive renal insufficiency, characterized histologically by diffuse mesangiolysis and mesangial sclerosis, endothelial lesions along with podocyte abnormalities such as widespread foot process effacement. Gene expression profiling revealed marked differences between these and the podocin-null mice, including significant perturbations of podocyte-expressed genes such as Cd2ap, Vegfa and the transcription factors Lmx1b and Zhx2. Upregulation of Serpine1 and Tgfb1 implicates these as potential mediators of disease progression in these mice. This mouse model of nephrotic syndrome may serve as a valuable tool in studies of in vivo intracellular protein trafficking of podocyte proteins, as well as testing therapeutic modalities aimed at correcting the targeting of mutant proteins.


Assuntos
Peptídeos e Proteínas de Sinalização Intracelular/genética , Proteínas de Membrana/genética , Mutação de Sentido Incorreto , Síndrome Nefrótica/genética , Animais , Modelos Animais de Doenças , Camundongos , Camundongos Mutantes , Índice de Gravidade de Doença , Fatores de Tempo
7.
Neurophysiol Clin ; 37(5): 299-309, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-18063232

RESUMO

Electroencephalography (EEG) recording techniques in early premature babies are not very different from those used for full-term neonates. Here, we emphasise the most important points: asepsis precautions, full knowledge of the clinical data and drug therapies, fundamental role of a well-trained technician in supervising the EEG recording and monitoring the baby. We discuss the best electrode positions, the most informative montages, and their standardisation between neurophysiological laboratories. Artefact detection constitutes an important aspect of EEG signal analysis in preterm babies of less than 30 weeks. It is obviously necessary to discriminate between meaningful information and artefacts. The complexity of the signal in neonates makes artefact detection difficult. We present some characteristic features and describe some methods for eliminating them. We underline the positive aspect of some artefacts and their clinical use. We emphasise the crucial role of the technicians.


Assuntos
Eletroencefalografia/métodos , Recém-Nascido/fisiologia , Recém-Nascido Prematuro/fisiologia , Artefatos , Assepsia , Interpretação Estatística de Dados , Eletroencefalografia/estatística & dados numéricos , Humanos , Lactente
8.
Neurophysiol Clin ; 37(5): 325-70, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-18063234

RESUMO

Pathological features on very premature EEG concern background abnormalities and abnormal ictal and nonictal patterns. Positive rolandic sharp waves keep an important place regarding diagnosis and prognosis of white-matter lesions. Background abnormalities, that may be classified as acute-stage or chronic-stage abnormalities, give essential complementary information. These abnormal patterns remain precocious markers of cerebral lesions and are complementary to cerebral imaging. Analysis of these abnormalities has always to take into account medication received by the baby during the recording and that could modify the EEG.


Assuntos
Encefalopatias/fisiopatologia , Eletroencefalografia , Epilepsia/fisiopatologia , Recém-Nascido Prematuro/fisiologia , Envelhecimento/fisiologia , Encefalopatias/diagnóstico , Fármacos do Sistema Nervoso Central/farmacologia , Epilepsia/diagnóstico , Idade Gestacional , Humanos , Lactente , Recém-Nascido , Prognóstico , Convulsões/diagnóstico , Convulsões/fisiopatologia
9.
Neurophysiol Clin ; 37(3): 149-61, 2007.
Artigo em Francês | MEDLINE | ID: mdl-17889791

RESUMO

EEG recording techniques in early premature babies are not very different from those used for full-term neonates. Here, we emphasise the most important points: asepsis precautions, full knowledge of the clinical data and drug therapies, the fundamental role of a well-trained technician in supervising the EEG recording and monitoring the baby. The best electrode positions, the most informative montages and their standardisation between neurophysiological laboratories, are suggested. Artifact detection constitutes an important aspect of EEG signal analysis in preterm babies of less than 30 weeks. It is obviously necessary to discriminate between meaningful information and artefacts. The complexity of the signal in neonates makes artifact detection difficult. We present some characteristic features and describe some methods for eliminating them. We underline the positive aspect of some artifacts and their clinical use. We emphasise the crucial role of the technicians.


Assuntos
Eletroencefalografia/métodos , Eletroencefalografia/estatística & dados numéricos , Recém-Nascido Prematuro/fisiologia , Artefatos , Encéfalo/fisiologia , Interpretação Estatística de Dados , Eletrocardiografia , Eletrodos , Eletromiografia , Humanos , Recém-Nascido , Movimento/fisiologia
10.
Neurophysiol Clin ; 37(3): 177-221, 2007.
Artigo em Francês | MEDLINE | ID: mdl-17889793

RESUMO

Pathological features on very premature EEG concern background abnormalities and abnormal patterns. Positive rolandic sharp waves keep an important place regarding diagnosis and prognosis. Background abnormalities give essential complementary informations. Unusual patterns (abnormal localisation or morphological aspect, high amplitude) remain early markers of cerebral lesions. Analysis of these pathological features must always take into account treatment given to the baby, which can by itself modify the EEG.


Assuntos
Doenças do Prematuro/diagnóstico , Recém-Nascido Prematuro/fisiologia , Feminino , Humanos , Recém-Nascido , Doenças do Prematuro/classificação , Doenças do Prematuro/tratamento farmacológico , Masculino , Doenças do Sistema Nervoso/diagnóstico , Doenças do Sistema Nervoso/tratamento farmacológico , Prognóstico
11.
Int J Environ Res Public Health ; 3(1): 48-66, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16823077

RESUMO

In this paper we report on the collection of fine (PM1) and ultrafine (PM0.1), or nanoparticulate, carbonaceous materials using thermophoretic precipitation onto silicon monoxide/formvar-coated 3 mm grids which were examined in the transmission electron microscope (TEM). We characterize and compare diesel particulate matter (DPM), tire particulate matter (TPM), wood burning particulate matter, and other soot (or black carbons (BC)) along with carbon nanotube and related fullerene nanoparticle aggregates in the outdoor air, as well as carbon nanotube aggregates in the indoor air; and with reference to specific gas combustion sources. These TEM investigations include detailed microstructural and microdiffraction observations and comparisons as they relate to the aggregate morphologies as well as their component (primary) nanoparticles. We have also conducted both clinical surveys regarding asthma incidence and the use of gas cooking stoves as well as random surveys by zip code throughout the city of El Paso. In addition, we report on short term (2 day) and longer term (2 week) in vitro assays for black carbon and a commercial multiwall carbon nanotube aggregate sample using a murine macrophage cell line, which demonstrate significant cytotoxicity; comparable to a chrysotile asbestos nanoparticulate reference. The multi-wall carbon nanotube aggregate material is identical to those collected in the indoor and outdoor air, and may serve as a surrogate. Taken together with the plethora of toxic responses reported for DPM, these findings prompt concerns for airborne carbonaceous nanoparticulates in general. The implications of these preliminary findings and their potential health effects, as well as directions for related studies addressing these complex issues, will also be examined.


Assuntos
Poluentes Atmosféricos/toxicidade , Sobrevivência Celular/efeitos dos fármacos , Humanos , México , Microscopia Eletrônica de Transmissão , Nanopartículas , Texas
12.
J Nanosci Nanotechnol ; 4(7): 716-8, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15570950

RESUMO

Carbon nanotubes and other aggregated fullerene-related multi-layer shell structures have been collected in propane and natural gas flame emissions from domestic cooking stoves and observed by transmission electron microscopy. Some aggregated nanoparticles collected on 3 mm electron microscope grids by thermal precipitation were mostly multi-walled nanotubes; many tangled and distorted, and aggregated with other closed-concentric, multi-shell forms. Such clean-burning regimes may be major contributors to complex particulate matter in indoor and outdoor air.


Assuntos
Fulerenos/química , Microscopia Eletrônica de Transmissão/métodos , Nanotecnologia/métodos , Nanotubos de Carbono/química , Propano/química , Poluição do Ar em Ambientes Fechados , Carbono/química , Culinária , Combustíveis Fósseis , Temperatura Alta , Fatores de Tempo
13.
Water Res ; 38(19): 4282-96, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15491674

RESUMO

Particulates extracted from a single section of a 10,000 year-old ice core melt sample exhibited characteristics of contemporary, airborne fine particulates: a majority were microcrystalline particulates and aggregated microcrystals, including some mixtures of microcrystals and carbonaceous matter. Particularly significant were the presence of carbon nanotubes and fullerene nanocrystals composing aggregated particulates reflecting global combustion products similar to contemporary, airborne carbon nanocrystal aggregates. ICP elemental analysis of the melt water showed significant concentrations of Ca, K and especially Na (corresponding to K, NaCl), S, Si, Se, and Zn. Overall, the elemental analysis of the melt water is similar to local tap water. However, lead was absent in the local tap water and only half the concentration of selenium was present in the tap water in contrast to the ice core water. While these observations cannot be generalized, the methodology illustrates the potential to characterize and compare airborne particulate regimes and water chemistries in antiquity.


Assuntos
Compostos Inorgânicos de Carbono/análise , Gelo , Água/química , Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Tamanho da Partícula , Fatores de Tempo
14.
J Mater Sci Mater Med ; 15(3): 237-47, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15334995

RESUMO

Airborne aggregates of nanoparticulates were collected on carbon/form-coated, 100-mesh Ni TEM grids in a thermal precipitator and observed in an analytical TEM utilizing a BF-SAED-DF-EDS characterization protocol to identify the nanocrystalline or nanoparticulate components, especially their degree of crystallinity, size, structural/morphologic features, and chemistries. Reference aggregates of TiO2 rutile and anatase as well as Si3N4 nanoparticles were used to establish these characterization protocols, which were applied to several hundred individual particulates: homogeneous aggregates of carbonaceous/diesel particulate matter, complex mixtures of carbonaceous matter, including carbon nanocrystals, and inorganic nanocrystals; and heterogeneous, nanocrystal/nanoparticulate aggregates. Most airborne particulates were aggregates ranging in aerodynamic diameters from a few nanometers to a few microns; containing as few as 2 nanocrystals to several thousand nanocrystals or nanoparticulates such as carbonaceous spherules arranged in complex branched homogeneous aggregates composing diesel exhaust, with spherule diameters ranging from 10 to 30 nm. The potential for ultrafine airborne aggregates to fragment into hundreds or thousands of nanoparticulate components in human airways and act as toxic agents in deep lung tissue is demonstrated.


Assuntos
Poluentes Atmosféricos/química , Poluentes Atmosféricos/toxicidade , Sistema Respiratório/efeitos dos fármacos , Carbono , Cristalização , Humanos , Técnicas In Vitro , Compostos Inorgânicos , Microscopia Eletrônica , Nanotubos , Tamanho da Partícula , Análise Espectral
15.
Cir. Esp. (Ed. impr.) ; 69(4): 358-361, abr. 2001.
Artigo em Es | IBECS | ID: ibc-1067

RESUMO

Introducción. El antígeno prostático específico (PSA) es una serinproteasa que puede ser detectada en las secreciones mamarias. Su comportamiento parece ser opuesto al de otros marcadores tumorales y puede ayudar a establecer el diagnóstico de carcinomas mamarios. Hemos realizado el presente trabajo con objeto de estudiar su comportamiento en secreciones mamarias no malignas. Pacientes y métodos. Hemos determinado, mediante un fluoroinmunoanálisis (EG&G Wallac, Finlandia) las concentraciones de PSA en 79 secreciones mamarias, correspondiendo a 67 ectasias ductales, 5 mastitis y 7 papilomas intraductales. Resultados. En las ectasias ductales los valores de PSA estuvieron comprendidos entre 0,1 y 89,9 ng/ml (mediana 6,0) y fueron mayores (p = 0,085) en la fase luteínica (intervalo: 0,189,9; mediana 9,2) que en la folicular (intervalo: 0,1-81 ng/ml; mediana 5,8). En las mastitis las cifras de PSA estuvieron comprendidas entre 0,1 y 375 ng/ml (mediana 33), mientras que en los papilomas intraductales oscilaron entre 0,1 y 23 ng/ml (mediana 0,1). Observamos sólo diferencias significativas (p = 0,010) entre las concentraciones del PSA de las ectasias y papilomas. Cifras de PSA superiores a 1 ng/ml se constataron en 48 de las 67 ectasias, 4 de las 5 mastitis y 2 de los 7 papilomas. Conclusiones. Los resultados anteriores nos sugieren que es posible detectar altas concentraciones de PSA en las secreciones mamarias por procesos no malignos mamarios, principalmente ectasias y mastitis, mientras que en los papilomas intraductales las concentraciones antigénicas fueron mucho menores. Asimismo, nuestros resultados apoyan la posible utilidad del PSA en las secreciones mamarias como indicador de riesgo de cáncer de mama tal como han sugerido ciertos grupos (AU)


Assuntos
Feminino , Humanos , Mama , Biomarcadores Tumorais , Secreções Corporais , Antígeno Prostático Específico , Neoplasias da Mama
16.
Rev Esp Med Nucl ; 20(1): 19-22, 2001 Feb.
Artigo em Espanhol | MEDLINE | ID: mdl-11181325

RESUMO

In order to study the behavior of the carcinoembryonic antigen (CAE), we assayed the concentrations of CEA in 67 nipple discharges of women with duct ectasia of the breast by means of a fluoroimmunoassay (EG & G. Wallac. Finland). The CEA concentrations ranged from 0.1 to 854 ng/ml (median 38.7), these being higher (p: 0.065) in the luteal phase (34 cases; range: 5.0-854, median 61.7) than in follicular phase of the menstrual cycle (29 cases; range: 0.1-452; median 30.5). Concentrations greater than 400 ng/ml were observed in two cases (2.98%) and none of the cases showed CEA values higher than 1000 ng/ml. Our results suggest that nipple discharges by ductal ectasia of the breast can be associated with increases in CEA, which can be explained by its own physiopathology, although it rarely (3%) exceeded 400 ng/ml.


Assuntos
Líquidos Corporais/química , Doenças Mamárias/metabolismo , Mama/metabolismo , Antígeno Carcinoembrionário/análise , Mama/patologia , Doenças Mamárias/patologia , Dilatação Patológica , Feminino , Humanos , Menopausa , Ciclo Menstrual , Mamilos
17.
Rev. esp. med. nucl. (Ed. impr.) ; 20(1): 19-22, feb. 2001.
Artigo em Es | IBECS | ID: ibc-801

RESUMO

Con objeto de estudiar su comportamiento, hemos determinado, mediante un fluoroinmunoanálisis (EG & G. Wallac. Finlandia), las concentraciones del antígeno carcinoembrionario (CEA) en 67 secreciones mamarias por ectasia ductal. Aquellas oscilaron entre 0,1 y 854 ng/ml (mediana 38,7) y fueron superiores (p. 0,065) en la fase luteínica (34 casos; i: 5,0-854, mediana 61,7) que en la folicular (29 casos; i: 0,1-451, mediana 30,5 ng/ml). Concentraciones > 400 ng/ml fueron constatadas en 2 casos (2,98 por ciento) y en ninguna ocasión se superaron los 1.000 ng/ml. Nuestros resultados nos sugieren que las secreciones mamarias por ectasia ductal pueden cursar con incrementos de CEA, hecho que se puede explicar por su propia fisiopatología, si bien raras veces (3 por ciento) se superaron los 400 ng/ml. (AU)


Assuntos
Feminino , Humanos , Menopausa , Ciclo Menstrual , Mamilos , Doenças Mamárias , Líquidos Corporais , Mama , Antígeno Carcinoembrionário , Dilatação Patológica
18.
Ginecol Obstet Mex ; 67: 75-9, 1999 Feb.
Artigo em Espanhol | MEDLINE | ID: mdl-10327769

RESUMO

The objective of this study was to know if there is a correlation in contents progesterone receptors (RPg) in biopsies from patients pre and postmenopausal, with normal cervix, Low-Grade squamous intraepithelial lesions (LGESIL) and High-Grade (HGSIL), and invasive cancer. Sixty three patients with abnormal cytology; colposcopy was carried out and two biopsies were taken from the suspicious lesion, they were sent for histopathological study, and for RPg; both studies were correlated later. Both pre and postmenopausal with LGSIL, the RPg the mean values were 16.81 fmol/mg, protein, and values negative, respectively. With regard to HGSIL, the RPg content, the mean values was 20.31 fmol/mg, protein in pre-menopausal patients, whereas it was 3.8 fmol/mg, protein in postmenopausal patients. It was seen that RPg concentration is higher in invasive cancer than to LGSIL and HGSIL patients in pre and postmenopausal. It is concluded that this study on quantification to RPg receptor level measurement may well be to select poor prognostic groups of patients for inclusion in the management of squamous intraepithelial lesions and invasive cancer.


Assuntos
Carcinoma de Células Escamosas/diagnóstico , Receptores de Progesterona/análise , Displasia do Colo do Útero/patologia , Neoplasias do Colo do Útero/patologia , Adulto , Idoso , Biópsia , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/cirurgia , Colo do Útero/química , Diagnóstico Diferencial , Feminino , Humanos , Pessoa de Meia-Idade , Pós-Menopausa , Pré-Menopausa , Prognóstico , Resultado do Tratamento , Neoplasias do Colo do Útero/cirurgia , Displasia do Colo do Útero/cirurgia
19.
Endocrine ; 11(1): 75-82, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10668645

RESUMO

Previous experiments from our laboratory and others have shown that the peptide antigonadotropic decapeptide (AGD) has marked inhibitory effects on luteinizing hormone (LH) secretion in rats and ewes. The first objective of this study was to determine whether AGD inhibits LH secretion by regulating hypothalamic release of gonadotropin hormone (GnRH). AGD (200 microg in 200 microL of 0.3% bovine serum albumin [BSA] saline) or vehicle was infused into the lateral ventricle of ovariectomized (OVX) ewes with hypophyseal-portal cannulae, and GnRH secretion was monitored. The frequency of GnRH and LH pulses in AGD-treated ewes was significantly decreased (p < 0.05) but did not change in the control ewes. The second objective of this investigation was to evaluate changes in hypothalamic sensitivity to AGD in the ewe during the estrous cycle and nonbreeding season. During the estrous cycle, the effects of AGD on LH secretion were assessed following ovariectomy, during the metestrous, diestrous, and proestrous phases of the estrous cycle. The response to AGD during the estrous cycle was compared to its effect during the anestrous season. LH, cortisol, and prolactin (PRL) concentrations were assayed in peripheral blood samples obtained at 10-min intervals over a 6-h period prior to injection of either vehicle (200 microL of 0.3% BSA in 0.9% saline) or AGD (200 microg in 200 microL of vehicle), and for an additional 10 h following treatment. LH pulse frequency decreased after treatment with AGD (p < 0.05) at all times in OVX and intact ewes compared to vehicle-treated controls. During the anestrous season, AGD treatment was more effective in inhibiting LH pulse frequency than during the breeding season (p < 0.05). Furthermore, there was a significant increase (p < 0.05) in mean cortisol concentrations after AGD infusion in all AGD-treated groups compared to controls independent of season or reproductive status. PRL concentrations were also increased (p < 0.05) following treatment with AGD. These results suggest that inhibition of pulsatile LH release induced by AGD is modulated by alterations in frequency of hypothalamic discharges of GnRH. Furthermore, changes in the inhibitory actions of AGD may contribute to the seasonal regulation of hypothalamic GnRH secretion in the ewe.


Assuntos
Anestro/fisiologia , Estro/fisiologia , Hormônio Liberador de Gonadotropina/metabolismo , Antagonistas de Hormônios/farmacologia , Hipotálamo/metabolismo , Peptídeos/farmacologia , Animais , Química Encefálica/efeitos dos fármacos , Depressão Química , Feminino , Hormônio Liberador de Gonadotropina/fisiologia , Hidrocortisona/metabolismo , Hipotálamo/química , Hipotálamo/efeitos dos fármacos , Hormônio Luteinizante/fisiologia , Ovariectomia , Prolactina/metabolismo , Ovinos
20.
Endocrine ; 8(3): 225-9, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9741826

RESUMO

Gonadotropin-releasing hormone (GnRH) receptor expression is regulated by estradiol and GnRH itself. The objective of this experiment was to determine the extent to which low levels of estradiol, similar to those observed during the transition from the luteal to the follicular phase of the estrous cycle, and GnRH interact to regulate expression of GnRH receptors and GnRH receptor mRNA. Ewes were ovariectomized (OVX) at least 2 wk prior to initiation of the experiment, and the pituitary gland was surgically disconnected from the hypothalamus to remove ovarian and hypothalamic inputs to the pituitary. Within 24 h after hypothalamic-pituitary disconnection, ewes received pulses of GnRH (250 ng/pulse) every 2 h for 6 d. At the end of 6 d, ewes were randomly assigned to treatments in a 2 x 2 factorial arrangement as follows: half of the animals received a single estradiol implant and half received an empty implant (placebo). At the same time, animals also received one of the following treatments: (1) saline or (2) GnRH (100 ng/pulse/2 h). Additionally, one group of ewes was ovariectomized, but not subjected to hypothalamic-pituitary disconnection (OVX controls). Blood samples were collected 15 min prior to each pulse of GnRH or saline and at 15-min intervals for 1 h after each pulse until tissues were collected and concentrations of luteinizing hormone (LH) were determined. Anterior pituitaries were collected 24 h after implant insertion to quantitate steady-state amounts of GnRH receptor mRNA and numbers of GnRH receptors. Mean LH was greatest in ovariectomized control ewes compared to all other treatments (p < 0.05). Mean LH and LH pulse amplitude in the placebo and GnRH-treated group most closely mimicked LH secretion in ovariectomized control animals. Mean LH and LH pulse amplitude were similar between both GnRH-treated groups (p < 0.05). Mean LH and LH pulse amplitude were significantly lower in all animals treated with saline compared to OVX controls (p < 0.05). Treatment with an estradiol implant and pulsatile GnRH increased (p < 0.05) relative amounts of GnRH receptor mRNA and the number of GnRH receptors compared to all other treatments. There were no differences in GnRH receptor expression between the remaining treatment groups (p > 0.05). Therefore, in OVX ewes after hypothalamic-pituitary disconnection, low levels of estradiol and GnRH are required to increase GnRH receptor mRNA and GnRH receptor numbers. Since we only observed an increase in GnRH receptor expression in the presence of both estradiol and GnRH, we conclude that there is a synergistic interaction between these two hormones in the regulation of GnRH receptor expression.


Assuntos
Estradiol/fisiologia , Hormônio Liberador de Gonadotropina/fisiologia , Sistema Hipotálamo-Hipofisário/fisiologia , Receptores LHRH/biossíntese , Animais , Estradiol/farmacologia , Feminino , Hormônio Luteinizante/sangue , Ovariectomia , Adeno-Hipófise/efeitos dos fármacos , Adeno-Hipófise/metabolismo , RNA Mensageiro/metabolismo , Receptores LHRH/genética , Ovinos
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