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1.
AJNR Am J Neuroradiol ; 42(5): 969-974, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33766829

RESUMEN

BACKGROUND AND PURPOSE: MR imaging has a key role in predicting neurodevelopmental outcomes following neonatal hypoxic-ischemic encephalopathy (HIE). A novel MR imaging scoring system for hypoxic-ischemic brain injury was used in our patient population with the aim of assessing interobserver variability and developing subcategories for the severity of brain injury. MATERIALS AND METHODS: We evaluated brain MR images of 252 infants who underwent hypothermia for HIE between 2014 and 2019. First, 40 infants were selected randomly to test interobserver variability. Discrepancies were identified during the assessment of the first 20 MR images. The remaining 20 MR images were scored after adjusting the scoring system. Second, we determined cutoff values for the severity of injury that were based on the percentiles of the total scores in the full cohort. RESULTS: The interobserver reliability showed excellent agreement for the total score both before (intraclass correlation coefficient = 0.96; 95% CI 0.89-0.99) and after the adjustment (intraclass correlation coefficient = 0.96; 95% CI, 0.89-0.98). The average of the differences and the agreement interval between the 2 readers decreased after the adjustment. Subcategories of brain injury were the following: We considered a total score of ≤4 (≤75%) as normal, 5-10 (76%-90%) as mild, 11-15 (91%-95%) as moderate, and >15 (>95%) as severe brain injury. The agreement on the classification of brain injury improved in the second epoch (weighted κ = 0.723 versus 0.887). CONCLUSIONS: The adjusted scoring system may lead to a higher degree of interrater agreement. The presented cutoff values may be used to determine the severity of brain injury in future clinical studies including infants with mild hypoxia-ischemia.


Asunto(s)
Hipoxia-Isquemia Encefálica/diagnóstico por imagen , Hipoxia-Isquemia Encefálica/patología , Imagen por Resonancia Magnética/métodos , Estudios de Cohortes , Femenino , Humanos , Hipotermia Inducida , Hipoxia-Isquemia Encefálica/terapia , Recién Nacido , Masculino , Variaciones Dependientes del Observador , Pronóstico , Reproducibilidad de los Resultados
2.
Annu Int Conf IEEE Eng Med Biol Soc ; 2019: 6553-6556, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31947343

RESUMEN

Magnetic Resonance Imaging (MRI) can provide 3D morphological information on brain structures. Such information is particularly relevant for carrying out morphometric brain analysis, especially in the newborn and in the case of prematurity. However, 3D neonatal MRI acquired in clinical environments are low-resolution, anisotropic images, making segmentation a challenging task. In this context, preprocessing techniques aim to increase the image resolution. Interpolation techniques were classically used; super-resolution (SR) techniques have recently appeared as an emerging alternative. In this paper, we evaluate the performance of different SR methods against the classical interpolation in the application of neonatal cortex segmentation. Additionally, we assess the robustness of different segmentation methods for each estimation of high resolution MRI input. Results are evaluated both qualitatively and quantitatively with neonatal clinical MRI.


Asunto(s)
Algoritmos , Imagen por Resonancia Magnética , Anisotropía , Encéfalo , Humanos , Recién Nacido , Manejo de Especímenes
3.
Am J Primatol ; 77(3): 338-45, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25328141

RESUMEN

When confronted with tasks involving reasoning instead of simple learning through trial and error, lemurs appeared to be less competent than simians. Our study aims to investigate lemurs' capability for transitive inference, a form of deductive reasoning in which the subject deduces logical conclusions from preliminary information. Transitive inference may have an adaptative function, especially in species living in large, complex social groups and is proposed to play a major role in rank estimation and establishment of dominance hierarchies. We proposed to test the capacities of reasoning using transitive inference in two species of lemurs, the brown lemur (Eulemur fulvus) and the black lemur (Eulemur macaco), both living in multimale-multifemale societies. For that purpose, we designed an original setup providing, for the first time in this kind of cognitive task, pictures of conspecifics' faces as stimuli. Subjects were trained to differentiate six photographs of unknown conspecifics named randomly from A to F to establish the order A > B > C > D > E > F and select consistently the highest-ranking photograph in five adjacent pairs AB, BC, CD, DE, and EF. Then lemurs were presented with the same adjacent pairs and three new and non-adjacent pairs BD, BE, CE. The results showed that all subjects correctly selected the highest-ranking photograph in every non-adjacent pair, reflecting lemurs' capacity for transitive inference. Our results are discussed in the context of the still debated current theories about the mechanisms underlying this specific capacity.


Asunto(s)
Cognición/fisiología , Aprendizaje/fisiología , Lemur/fisiología , Animales , Femenino , Masculino , Especificidad de la Especie
4.
Am J Primatol ; 70(2): 161-8, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17823917

RESUMEN

In their natural environment, capuchins select certain plants, containing secondary compounds with bactericide, insecticide or fungicide properties, to rub their pelage energetically (i.e. fur rubbing). Fur rubbing can be performed in solitary, or collectively in subgroups of variable size and composition, and most of the time fur rubbing happens in synchrony with other group members. The aim of this study is to understand the underlying mechanisms of this phenomenon, and, more particularly, to determine the processes involved in its synchronization. For this purpose, we designed a set of experiments where white-faced capuchins (Cebus capucinus) were presented with onions (Allium cepa) that they use to fur rub. We conducted a detailed kinetic study of fur rubbing behavior to determine if its synchronization is the consequence of simultaneous responses of different individuals to the same stimulus or if, on the contrary, there is a real collective phenomenon where individuals respond to conspecific behavior. Our results reveal that fur rubbing is a collective behavior with a mimetic underlying mechanism. If fur rubbing with onions (a plant with antifungal and repellent properties) allows capuchins to treat their fur against parasites or pathogens, its synchronization would optimize the treatment by acting as a group barrier to ectoparasite propagation.


Asunto(s)
Cebus/fisiología , Aseo Animal/fisiología , Cabello , Facilitación Social , Animales , Simulación por Computador , Observación , Grabación en Video
5.
Behav Processes ; 77(3): 320-6, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17766057

RESUMEN

Self-medicative behaviours have been largely documented in vertebrates and, in particular, the use of plants for pharmacological purposes has been mainly reported in primates. White-faced capuchins are known to rub specifically chosen plants and other substances on their fur. To better understand the mechanisms underlying this phenomenon and investigate the influence of different plant resources on the form of fur rubbing activity, we conducted experiments using different randomly selected plant items: oranges and onions. We found that (1) capuchins showed different degrees of interest in the materials used to fur rub; (2) the mean group dynamics differ drastically according to the resource supplied; and (3) individuals present strong differences in their social behaviour, i.e. they spent more or less time fur rubbing in spatial proximity of conspecifics according to the material used for fur rubbing. We propose hypotheses on possible proximal causes for these differences and highlight that some precautions have to be taken in behavioural studies including only one resource type.


Asunto(s)
Cebus/psicología , Conducta de Elección , Aseo Animal , Conducta Social , Animales , Baños , Citrus , Conducta Exploratoria , Femenino , Masculino , Cebollas , Plantas Medicinales , Automedicación , Medio Social , Estadísticas no Paramétricas
6.
Radiat Prot Dosimetry ; 99(1-4): 47-8, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12194356

RESUMEN

The structure of the survival curve of melanoma cells irradiated by 14 MeV neutrons displays unusual features at very low dose rate where a marked increase in cell killings at 0.05 Gy is followed by a plateau for survival from 0.1 to 0.32 Gy. In parallel a simulation code was constructed for the interaction of 14 MeV neutrons with cellular cultures. The code describes the interaction of the neutrons with the atomic nuclei of the cellular medium and of the external medium (flask culture and culture medium), and is used to compute the deposited energy into the cell volume. It was found that the large energy transfer events associated with heavy charged recoils can occur and that a large part of the energy deposition events are due to recoil protons emitted from the external medium. It is suggested that such events could partially explain the experimental results.


Asunto(s)
Supervivencia Celular/efectos de la radiación , Neutrones , Simulación por Computador , Relación Dosis-Respuesta en la Radiación , Humanos , Melanoma , Radiometría/métodos , Dispersión de Radiación , Células Tumorales Cultivadas
7.
J Comp Neurol ; 364(3): 473-493, 1996 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-8820878

RESUMEN

Inhibin and activin are best known as gonadal glycoprotein hormones but have a broad anatomical distribution. We previously described the central distribution ofinhibin/activin beta A- and beta B-subunit proteins in some neuronal cell bodies, fibers, and nuclei of the rat brain and reported a possible role for central activin in suckling-induced oxytocin secretion and corticotropin releasing factor release. In the present report, we mapped the detailed immunohistochemical localization of inhibin/activin alpha-, beta A-, and beta B-subunits throughout the rat brain to further clarify their central distribution. In addition, the localization and distribution of their corresponding mRNAs was assessed. The results are summarized as follows: 1) Both beta A- and beta B-subunit immunoreactivity are found in neuronal cell bodies in the nucleus of the solitary tract and the dorsal and ventral medullary reticular nuclei, and in fibers and terminals of known projection sites for these nuclei. 2) beta B-subunit immunoreactivity is localized in a group of perifornical neurons in the hypothalamus. 3) beta A-subunit immunoreactivity is present in discrete populations of neuronal cell nuclei scattered throughout the CNS. 4) mRNAs encoding each of the inhibin/activin subunits are expressed in all major brain regions as determined by S1 nuclease assay and in a variety of specific neuroanatomical sites as shown by in situ hybridization. The results suggest that central inhibin and activin proteins are produced in the brain where they may potentially serve inter- and intracellular functions in multiple systems.


Asunto(s)
Química Encefálica/fisiología , Inhibinas/metabolismo , ARN Mensajero/metabolismo , Activinas , Animales , Encéfalo/anatomía & histología , Femenino , Inmunohistoquímica , Hibridación in Situ , Masculino , Sondas ARN , Ratas , Ratas Sprague-Dawley , Endonucleasas Específicas del ADN y ARN con un Solo Filamento/análisis
8.
Phys Rev Lett ; 70(23): 3565-3568, 1993 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-10053906
9.
Nat Genet ; 3(2): 157-64, 1993 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-7684647

RESUMEN

Severely reduced fertility is a common finding in cystic fibrosis (CF). We used in situ hybridization to examine the cell-specific expression of CFTR in the reproductive organs of rodents. In males CFTR mRNA is found in the round spermatids (spermatogenic stages V-X) and in the principal cells that line the initial segment of the epididymis. In both the testis and the epididymis, CFTR expression is developmentally regulated suggesting that the defect in the genital tract of male CF patients is of developmental origin. CFTR expression in the luminal and glandular epithelium of the uterus is regulated during the oestrous cycle and is maximal at pro-oestrus. Our results provide a biological rationale for the reduced fertility of CF patients, and suggest a possible cause for the comparatively poorer prognosis for women with CF.


Asunto(s)
Fibrosis Quística/genética , Infertilidad/genética , Proteínas de la Membrana/genética , Animales , Fibrosis Quística/complicaciones , Fibrosis Quística/fisiopatología , Regulador de Conductancia de Transmembrana de Fibrosis Quística , Epidídimo/fisiopatología , Estro/genética , Estro/fisiología , Femenino , Regulación de la Expresión Génica , Hibridación in Situ , Infertilidad/etiología , Infertilidad/fisiopatología , Masculino , Proteínas de la Membrana/fisiología , Ratones , Sondas Moleculares , Ratas , Ratas Wistar , Epitelio Seminífero/fisiopatología , Espermatogénesis/genética
11.
Am J Obstet Gynecol ; 165(3): 750-8, 1991 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-1892206

RESUMEN

This study describes the difference in distribution and levels of inhibin alpha, beta A- and beta B-subunit messenger ribonucleic acids in human placenta during pregnancy. Northern blot analysis indicated that inhibin alpha messenger ribonucleic acid is present in placental extracts collected at the early stage of gestation. Hybridization to inhibin beta A messenger ribonucleic acid was detected in the first trimester but in much lower levels. However, the intensity of the hybridization signal for inhibin alpha- and beta A-subunit messenger ribonucleic acids was greater in extracts prepared from term placentas than in those from the first or second trimester of pregnancy. Low levels of inhibin beta B-subunit messenger ribonucleic acid were observed only in extracts prepared from term placenta. At both early stage and term gestation trophoblast cells showed a positive fluorescent signal with the inhibin alpha-, beta A- and beta B-subunit-specific antisera. However, whereas inhibin alpha-subunit was localized in the cytotrophoblast, inhibin beta B-subunit immunoreactivity was observed in the syncytial layer of the villi, and inhibin beta A-subunit was widely distributed. The different distribution of immunoreactive inhibin subunits was confirmed by in situ hybridization, showing the different localizations of the inhibin messenger ribonucleic acids. These results showed that (1) human placenta produces the inhibin alpha- and beta A-subunits as early as the first trimester of pregnancy, (2) messenger ribonucleic acid levels for each of the three inhibin subunits are highest at term, and (3) immunoreactive inhibin subunits are localized differently in placental villi.


Asunto(s)
Inhibinas/análisis , Placenta/química , ARN Mensajero/análisis , Femenino , Técnica del Anticuerpo Fluorescente , Humanos , Inhibinas/genética , Embarazo
12.
J Clin Endocrinol Metab ; 71(2): 487-92, 1990 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-2199480

RESUMEN

A growing number of studies provided the evidence that human decidua is a pregnancy-related tissue capable of hormone production and metabolism. The aim of the present study was to evaluate the possible presence of inhibin subunits in human decidua. Tissue samples were collected in pregnant women during the first (8 weeks) and second trimester (18 weeks) of gestation and at term (40 weeks). Immunohistochemical data were obtained using affinity purified polyclonal antisera raised in rabbit against porcine alpha, beta A, or beta B subunits. Levels of the respective inhibin subunits were evaluated by Northern blot analysis using cDNA probes encoding sequences corresponding to each subunit. The present results indicated that human decidua contains and synthesizes inhibin alpha, beta A, and beta B subunits. The immunohistochemical data showed that decidual cells were stained with both inhibin alpha and beta B antisera, showing a similar localization. On the other hand, cells stained with inhibin beta A antisera were sparse and followed a distribution pattern different from that of cells stained with alpha or beta B antisera. The first inhibin alpha and beta B subunit mRNAs were both expressed in first trimester of pregnancy, and those mRNA levels showed a gestational related increase. The beta A subunit mRNA was expressed at very low levels at term and could not be detected earlier during pregnancy. The present data showed that human decidua actively produces inhibin subunits with a gestational-related profile. The results suggest that decidua may be a further source of inhibin-related proteins during pregnancy and emphasize the endocrine competence of human decidua.


Asunto(s)
Decidua/metabolismo , Inhibinas/análisis , Aborto Espontáneo , Northern Blotting , Cesárea , Decidua/citología , Femenino , Técnica del Anticuerpo Fluorescente , Expresión Génica , Humanos , Inhibinas/biosíntesis , Inhibinas/genética , Sustancias Macromoleculares , Embarazo , Primer Trimestre del Embarazo , ARN Mensajero/análisis , ARN Mensajero/genética , Valores de Referencia
13.
Acta Clin Belg ; 45(1): 42-6, 1990.
Artículo en Inglés | MEDLINE | ID: mdl-2161607

RESUMEN

A woman aged 62 developed a septic shock and pulmonary embolism after skin grafting for extensive burns. She was put on anticoagulants. A second shock led to renal insufficiency. Hypercalcaemia developed. A CT scan of the upper abdomen disclosed enlarged adrenal glands. An acute adrenal haemorrhage was suspected. The levels of cortisol were low in the plasma and urine and did not respond to ACTH stimulation. Cortisone replacement therapy improved the condition of the patient and normalized plasma calcium levels. The mechanisms of hypercalcaemia in acute adrenal insufficiency are discussed. Multiple factors have been proposed: haemoconcentration, an increased affinity of plasma proteins for calcium, an increase in the filtrable calcium complexes, and an enhanced calcium mobilization of skeletal origin.


Asunto(s)
Enfermedades de las Glándulas Suprarrenales/complicaciones , Insuficiencia Suprarrenal/complicaciones , Hemorragia/complicaciones , Hipercalcemia/etiología , Enfermedad Aguda , Enfermedades de las Glándulas Suprarrenales/etiología , Insuficiencia Suprarrenal/etiología , Quemaduras/complicaciones , Femenino , Humanos , Persona de Mediana Edad , Embolia Pulmonar/complicaciones , Choque Séptico/complicaciones , Estrés Fisiológico/complicaciones
15.
Mol Endocrinol ; 3(12): 2062-9, 1989 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-2628740

RESUMEN

Immature female rats were treated with PMSG and human CG to induce ovulation. Sequential treatment with these hormones allowed us to investigate variations in the production of inhibin subunits shortly before ovulation and during the induced luteal phase. Using this model, we found that expression patterns for the alpha-, beta A-, and beta B-subunits were similar to those observed in mature cycling animals: administration of PMSG (to mimic the gonadotropin surge) led to a sharp increase in the expression of all three subunits in large preovulatory follicles whereas injection with human CG (to induce ovulation) caused a decrease in the levels of the respective mRNAs. In contrast to mature females, shortly before ovulation, levels of inhibin alpha-subunit mRNA were low in small antral follicles (approximately 350 microns). In addition, at that time, inhibin beta A- and beta B-subunits mRNAs were present in several large follicles (greater than 500 microns). More than 2 days after ovulation, inhibin beta A- and beta B-subunit mRNAs could not be detected in small antral size follicles (approximately 350 microns) of hormonally induced females. On the other hand, hybridization signals for the inhibin alpha-subunit were observed in some small antral and preantral size follicles, while signals were very low or undetectable in a large number of atretic follicles. Using this synchronized ovulation model, hybridization patterns for inhibin beta A-subunit mRNA was observed in interstitial cells, 8-10 h after ovulation.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Gonadotropinas/farmacología , Inhibinas/genética , Folículo Ovárico/metabolismo , Ovulación , Animales , Gonadotropina Coriónica/farmacología , Femenino , Expresión Génica , Gonadotropinas Equinas/farmacología , Fase Luteínica , Modelos Biológicos , Folículo Ovárico/efectos de los fármacos , Conformación Proteica , ARN Mensajero/metabolismo , Ratas
16.
Endocrinology ; 125(5): 2350-9, 1989 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-2676482

RESUMEN

The distributions of the alpha-, beta A-, and beta B subunits of inhibin/activin polypeptides were studied in the testis of adult (60-day-old) and immature (12-day-old) rats. Immunohistochemical techniques using antisera selective for each subunit were used to localize the polypeptide chains. In situ hybridization using radiolabeled complementary RNA probes enabled localization of the messenger RNAs (mRNAs) encoding these subunits. In 12-day-old rats, immunostaining and mRNA signal for the alpha-subunit was found in Leydig cell clusters. The beta A- and beta B-subunit staining and beta A-subunit message were detectable in isolated interstitial cells, but the clusters appeared to lack these subunits. Positive immunostaining for each subunit was localized in a Sertoli cell-like pattern in seminiferous tubules, as was a positive mRNA signal for the alpha- and beta B-subunit over regions containing these cell types. Treatment with human CG (hCG) and PMSG greatly enhanced the production of the alpha-subunit in the Leydig cell clusters, but not within the tubules, of these young rats. In adult rats, alpha- and beta B-subunit staining, and alpha-subunit mRNA signal, was observed in the interstitial cells. As in the immature animals, all three subunits were localized in a Sertoli cell-like pattern in the tubules, and a positive mRNA signal for the alpha- and beta B-subunits was found over these cells. There was, however, no obvious change in the expression of the subunits in the testis of adult rats after gonadotropin treatment. The present findings suggest that: 1) in the rat testis, both Sertoli and interstitial cells produce inhibin/activin subunits; 2) the alpha- and beta-subunits are produced by different types of interstitial cells in immature rats; and 3) the production of the alpha-subunit in the Leydig cells of immature rats is regulated by LH-like hormones.


Asunto(s)
Regulación de la Expresión Génica , Inhibinas/biosíntesis , Testículo/crecimiento & desarrollo , Animales , Técnica del Anticuerpo Fluorescente , Sueros Inmunes , Inhibinas/genética , Células Intersticiales del Testículo/metabolismo , Sustancias Macromoleculares , Masculino , Hibridación de Ácido Nucleico , ARN Mensajero/análisis , ARN Mensajero/biosíntesis , ARN Mensajero/genética , Ratas , Ratas Endogámicas , Células de Sertoli/metabolismo , Maduración Sexual , Testículo/citología , Testículo/metabolismo
17.
Biol Reprod ; 41(5): 967-81, 1989 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-2483127

RESUMEN

Male rats were either unilaterally or bilaterally castrated, or were rendered cryptorchid when they were either 15 or 45 days old. Subsequently, blood was sampled over the next several weeks and plasma luteinizing hormone (LH), follicle-stimulating hormone (FSH), testosterone (T), and immunoreactive inhibin-alpha (irI alpha) levels were measured by specific radioimmunoassays (RIAs). At the end of the experiment, gonadal expression of inhibin-alpha, inhibin-beta A, and inhibin-beta B subunits was measured by S1 nuclease analysis and in situ hybridization. In both age groups, bilateral castration (BC) produced the expected marked (p less than or equal to 0.01) increases in plasma LH and FSH levels, and concomitant decreases in T and irI alpha secretion within 1 - 2 days after surgery. In 15-day-old animals, unilateral castration (UC) significantly increased FSH and decreased circulating levels of irI alpha, but did not measurably alter LH or androgen production. At 7 days after surgery, the level of inhibin mRNA in the remaining testis was unchanged. In 45-day-old animals, UC caused a measurable increase in FSH, with little or no changes in the circulating levels of irI alpha. Plasma T levels were lowered (p less than or equal to 0.05) by UC; however, there were no statistical changes in LH levels in these UC rats. Finally, T administration markedly reversed UC-induced increase in FSH secretion in both age groups. Androgen therapy also interfered with inhibin release in 45-day-old, but not in 15-day-old rats. In rats 15 days old at the time of surgery, cryptorchidism produced a small but measurable increase (p less than or equal to 0.05) in LH release at Week 6 only, which was accompanied by a significant (p less than or equal to 0.01) decline in T secretion. Plasma FSH levels were elevated at all times in cryptorchid rats, and at 2, 4, and 6 wk, these levels were not statistically distinguishable (p greater than 0.05) from those of castrated animals. In this group of rats, cryptorchidism caused a transient increase (p less than or equal to 0.05) in irI alpha values 1 wk after surgery, but no changes at later times. Finally, measurement of testicular inhibin-alpha subunit messenger RNA (mRNA) levels showed an approximately 2-fold increase compared to total RNA levels in the testis. However, because of the significant decrease in total RNA levels per testis caused by cryptorchidism, the absolute change in inhibin-alpha subunit mRNA levels per testis corresponded to an approximately 3-fold decrease.(ABSTRACT TRUNCATED AT 400 WORDS)


Asunto(s)
Hormona Folículo Estimulante/metabolismo , Inhibinas/fisiología , Hormona Luteinizante/metabolismo , Animales , Criptorquidismo/metabolismo , Sondas de ADN , Implantes de Medicamentos , Expresión Génica , Inhibinas/genética , Inhibinas/metabolismo , Masculino , Hibridación de Ácido Nucleico , Orquiectomía , Tamaño de los Órganos , Hormonas Liberadoras de Hormona Hipofisaria/farmacología , ARN/análisis , ARN/genética , Radioinmunoensayo , Ratas , Ratas Endogámicas , Testículo/análisis , Testículo/anatomía & histología , Testículo/metabolismo , Testosterona/administración & dosificación , Testosterona/sangre , Testosterona/farmacología
18.
Endocrinology ; 124(1): 552-4, 1989 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-2535814

RESUMEN

Two related proteins, inhibin and activin, are produced and secreted by the gonads and act at the pituitary to regulate FSH secretion. In the present study, the alpha and beta B, but not the beta A, polypeptide subunits of inhibin were localized in the cytoplasm of FSH- and LH-immunoreactive (ir) gonadotropes. Ovariectomy (OVX) increased the size and number of cells immunoreactive for inhibin-alpha and -beta B as well as the mRNAs encoding these subunits. Treatment with estrogen prevented these effects. These results suggest that pituitary gonadotropes are sources, as well as targets, of inhibin-related peptides, whose expression in the pituitary is modulated by ovarian factors.


Asunto(s)
Hormona Folículo Estimulante/metabolismo , Inhibinas/biosíntesis , Hormona Luteinizante/metabolismo , Adenohipófisis/metabolismo , Animales , Citoplasma/metabolismo , Endonucleasas , Femenino , Técnica del Anticuerpo Fluorescente , Inhibinas/genética , Sustancias Macromoleculares , Masculino , Orquiectomía , Ovariectomía , ARN Mensajero/metabolismo , Ratas , Ratas Endogámicas , Endonucleasas Específicas del ADN y ARN con un Solo Filamento
19.
Acta Clin Belg ; 44(1): 24-30, 1989.
Artículo en Inglés | MEDLINE | ID: mdl-2763780

RESUMEN

Primary sclerosing cholangitis (PSC) and idiopathic pulmonary fibrosis (IPF) were each separately described in association with a variety of chronic idiopathic inflammatory diseases such as retroperitoneal fibrosis, Sicca complex or Riedel's thyroiditis. We report a case which may be the first description of the association between PSC and IPF. The physiopathogenic implications of such an association are discussed.


Asunto(s)
Colangitis Esclerosante/complicaciones , Fibrosis Pulmonar/complicaciones , Biopsia , Colangitis Esclerosante/diagnóstico por imagen , Colangitis Esclerosante/patología , Femenino , Humanos , Hígado/patología , Pulmón/patología , Persona de Mediana Edad , Fibrosis Pulmonar/diagnóstico por imagen , Fibrosis Pulmonar/patología , Radiografía
20.
Mol Endocrinol ; 2(12): 1352-63, 1988 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-3146021

RESUMEN

Distributions of inhibin alpha-, beta A-, and beta B-subunits in different ovarian compartments were studied in cycling female rats by in situ hybridization with complementary RNA probes and using immunohistochemical localization with antibodies selective for each inhibin subunit. Consistent with earlier studies showing inhibin production by granulosa cells of maturing follicles, we also detected mRNAs for inhibin alpha-, beta A-, and beta B-subunits in granulosa cells of these follicles. However, based on immunohistochemistry and in situ hybridization, we found that inhibin alpha- is not only expressed in granulosa cells of mature follicles but in follicles at all stages of maturation, including primary to tertiary follicles. A number of primordial follicles also contained alpha mRNA and immunodetectable alpha-subunit. Interestingly, theca interna and interstitial gland cells contained inhibin alpha mRNA and alpha-subunit. Low levels of inhibin alpha immunoreactivity as well as specific hybridization to the complementary inhibin alpha mRNA probe were observed in newly formed luteal tissue. beta-Subunits, on the other hand, were detected exclusively in granulosa cells of healthy tertiary follicles. The changes in expression of inhibin alpha-, beta A-, and beta B-subunits were more pronounced during the follicular phase of the cycle: inhibin alpha reached its highest level in granulosa cells, theca interna, and interstitial gland cells a few hours after the LH/FSH surge, while at the same time the beta-subunits decreased dramatically in granulosa cells of mature follicles. Immediately before ovulation (estrus 0200 h), the alpha-subunit sharply declined in preovulatory follicles and was present mainly in granulosa cells from nonovulatory follicles at various stages of maturation. At that time, the beta A- and beta B-subunits could not be detected in preovulatory follicles but were localized mainly in small tertiary follicles (less than 300 microns). Unlike for the alpha- and beta B-subunits, beta A mRNA and immunoreactivity was present in large tertiary follicles (approximately 600 microns) immediately before ovulation. The present findings support the hypothesis that a decrease in inhibin production could be responsible for the secondary FSH surge observed early on estrus. This could be initiated by a change in the ratios of activin-inhibin production by decreasing first, the levels of beta-subunits, second, the levels of alpha-subunit, and third, by a resurgence of activin A produced mainly by granulosa cells from large tertiary follicles.(ABSTRACT TRUNCATED AT 400 WORDS)


Asunto(s)
Estro/fisiología , Inhibinas/genética , Ovario/citología , Animales , Femenino , Hormona Folículo Estimulante/metabolismo , Regulación de la Expresión Génica , Inmunohistoquímica , Inhibinas/análisis , Inhibinas/metabolismo , Ovario/análisis , Ovario/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Ratas
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