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1.
Osteoporos Int ; 30(11): 2257-2269, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31372710

RESUMEN

Sheehan's syndrome (SHS) is a rare condition related to the risk of osteoporosis and evaluation of bone texture imaging features on panoramic radiographs would be suitable for this condition, which was the aim of the present study. Fractal dimension, lacunarity, and trabecular morphologic aspects were significantly altered in these patients. INTRODUCTION: SHS is an important public health problem particularly in developing countries. It is characterized as postpartum hypopituitarism secondary to obstetric complications-related ischemic pituitary necrosis that shows significant systemic metabolic repercussions. Thus, this study aimed to evaluate bone texture parameters in digital panoramic radiographs of patients with SHS. METHODS: A case-control study was conducted with 30 SHS patients from an Endocrinology and Diabetology Service of reference in Brazil, and 30 age- and sex-matched healthy controls. A custom computer program measured fractal dimension, lacunarity, and some morphologic features in the following mandibular regions of interest (50 × 50 pixels): below the mental foramen (F1), between the first and second molars (M1), and at the center of the mandibular ramus (R1). RESULTS: The fractal analysis showed a statistically significant difference between the studied groups in all regions of interest. The fractal dimension in F1 (p = 0.016), M1 (p = 0.043), and R1 (p = 0.028) was significantly lower in SHS group, as well as lacunarity in R1 (p = 0.008). Additionally, several morphologic features were statistically significant in the SHS group (p < 0.05). CONCLUSION: Therefore, individuals with SHS showed altered imaging texture parameters on panoramic radiographs, which reflect a smaller spatial organization of the bone trabeculae and, possibly, a state of reduced mineral bone density.


Asunto(s)
Densidad Ósea , Hipopituitarismo/diagnóstico por imagen , Hipopituitarismo/patología , Adolescente , Brasil , Hueso Esponjoso/diagnóstico por imagen , Hueso Esponjoso/patología , Estudios de Casos y Controles , Niño , Preescolar , Femenino , Fractales , Humanos , Lactante , Foramen Mental/diagnóstico por imagen , Foramen Mental/patología , Osteoporosis/epidemiología , Radiografía Panorámica , Adulto Joven
2.
Arq. bras. med. vet. zootec ; Arq. bras. med. vet. zootec. (Online);63(5): 1079-1086, out. 2011. ilus, tab
Artículo en Portugués | LILACS | ID: lil-605831

RESUMEN

Determinaram-se os parâmetros ecocardiográficos em modo-M normais de cães da raça Yorkshire Terrier. Foram utilizados 30 cães clinicamente sadios, com peso médio de 2,42±0,64kg e idades entre um e seis anos. O diâmetro do átrio esquerdo e da aorta, a dimensão interna do ventrículo esquerdo na diástole e na sístole, a espessura do septo interventricular na diástole e na sístole, e a espessura da parede posterior do ventrículo esquerdo na diástole e na sístole correlacionaram-se com o peso corporal. As demais variáveis do modo-M não se correlacionaram com peso corporal, sexo ou idade. Os valores ecocardiográficos obtidos neste estudo podem ser utilizados como referência para cães dessa raça.


The aim of this study was to establish the normal echocardiographic parameters in M-mode for Yorkshire Terrier dogs. Thirty clinically normal dogs with mean weight of 2.42±0.64kg and ages varying from one to six years old were studied. The left atrial diameter, the aortic diameter, the left ventricular internal dimension at end - diastole and end - systole, end - diastolic and end - systolic interventricular septal thickness, and end - diastolic and end - systolic left ventricular posterior wall thickness had correlation with body weight. The other M - mode variables showed no linear correlations with body weight, sex or age. The echocardiographic values found in this study can be used as reference for this breed.


Asunto(s)
Animales , Perros , Corazón/anatomía & histología , Perros , Estándares de Referencia , Ultrasonografía/veterinaria , Cardiopatías/veterinaria , Radiografía Torácica/veterinaria , Tórax/anatomía & histología
3.
Arq. bras. med. vet. zootec ; Arq. bras. med. vet. zootec. (Online);63(4): 850-857, ago. 2011. ilus, graf
Artículo en Portugués | LILACS | ID: lil-599603

RESUMEN

Determinou-se valor médio do vertebral heart size (VHS) em cães da raça Yorkshire Terrier. Foram selecionados 30 cães clinicamente normais, com média de peso de 2,42±0,64kg e idades entre um e seis anos. Os animais foram submetidos ao exame radiográfico do tórax nas projeções lateral direita, ventrodorsal e dorsoventral. Foram feitas mensurações para avaliação cardíaca e da profundidade e largura torácicas. O valor médio de VHS foi de 9,9±0,6 vértebras na projeção lateral, 10,1±0,6 vértebras na projeção ventrodorsal e 10,0±0,6 vértebras na projeção dorsoventral. Não houve diferença entre esses valores. Cinco animais (16,7 por cento) apresentaram VHS acima de 10,5 vértebras, valor sugerido como limite superior para a maioria das raças, em projeção lateral. Os valores de VHS correlacionaram-se com peso corporal nas projeções lateral e ventrodorsal. A razão profundidade:largura torácica apresentou valor médio de 0,75±0,06. Não foi observada correlação entre a qualidade do tórax e o VHS.


The mean vertebral heart size (VHS) was established for Yorkshire Terrier dogs. Thirty clinically normal dogs with mean weight of 2.42±0.64kg and ages varying from one to six years of age, were studied. The animals were submitted to right lateral, ventrodorsal and dorsoventral thoracic radiographs. The Buchanan e Bücheler method was applied to the cardiac silhouette and thoracic depth and width. The VHS was 9.9±0.6 vertebrae on lateral, 10.1±0.6 on ventrodorsal and 10.0±0.6 on dorsoventral radiographs. There was no difference among these values. Five animals (16.7 percent) presented VHS values exceeding 10.5, the value suggested as upper limit for most breeds in lateral view. However, 95 percent of the animals in this study provide VHS values below the upper limit, and this should be equal to 11 vertebrae. The VHS values had significant correlation with body weight on lateral and VD radiographs. The mean depth:width ratio was 0.75±0.06. There was no correlation among VHS and depth:width ratios.


Asunto(s)
Animales , Masculino , Femenino , Corazón/anatomía & histología , Corazón , Perros , Radiografía Torácica/veterinaria , Vértebras Torácicas , Radiografía/métodos , Tórax/anatomía & histología
4.
Arq. bras. med. vet. zootec ; 63(4): 850-857, 2011. ilus, graf
Artículo en Portugués | VETINDEX | ID: vti-1032

RESUMEN

Determinou-se valor médio do vertebral heart size (VHS) em cães da raça Yorkshire Terrier. Foram selecionados 30 cães clinicamente normais, com média de peso de 2,42±0,64kg e idades entre um e seis anos. Os animais foram submetidos ao exame radiográfico do tórax nas projeções lateral direita, ventrodorsal e dorsoventral. Foram feitas mensurações para avaliação cardíaca e da profundidade e largura torácicas. O valor médio de VHS foi de 9,9±0,6 vértebras na projeção lateral, 10,1±0,6 vértebras na projeção ventrodorsal e 10,0±0,6 vértebras na projeção dorsoventral. Não houve diferença entre esses valores. Cinco animais (16,7 por cento) apresentaram VHS acima de 10,5 vértebras, valor sugerido como limite superior para a maioria das raças, em projeção lateral. Os valores de VHS correlacionaram-se com peso corporal nas projeções lateral e ventrodorsal. A razão profundidade:largura torácica apresentou valor médio de 0,75±0,06. Não foi observada correlação entre a qualidade do tórax e o VHS.(AU)


The mean vertebral heart size (VHS) was established for Yorkshire Terrier dogs. Thirty clinically normal dogs with mean weight of 2.42±0.64kg and ages varying from one to six years of age, were studied. The animals were submitted to right lateral, ventrodorsal and dorsoventral thoracic radiographs. The Buchanan e Bücheler method was applied to the cardiac silhouette and thoracic depth and width. The VHS was 9.9±0.6 vertebrae on lateral, 10.1±0.6 on ventrodorsal and 10.0±0.6 on dorsoventral radiographs. There was no difference among these values. Five animals (16.7 percent) presented VHS values exceeding 10.5, the value suggested as upper limit for most breeds in lateral view. However, 95 percent of the animals in this study provide VHS values below the upper limit, and this should be equal to 11 vertebrae. The VHS values had significant correlation with body weight on lateral and VD radiographs. The mean depth:width ratio was 0.75±0.06. There was no correlation among VHS and depth:width ratios.(AU)


Asunto(s)
Animales , Masculino , Femenino , Perros , Corazón/anatomía & histología , Corazón , Radiografía Torácica/veterinaria , Vértebras Torácicas , Radiografía/métodos , Tórax/anatomía & histología
5.
Arq. bras. med. vet. zootec ; 63(5): 1079-1086, 2011. ilus, tab
Artículo en Portugués | VETINDEX | ID: vti-1066

RESUMEN

Determinaram-se os parâmetros ecocardiográficos em modo-M normais de cães da raça Yorkshire Terrier. Foram utilizados 30 cães clinicamente sadios, com peso médio de 2,42±0,64kg e idades entre um e seis anos. O diâmetro do átrio esquerdo e da aorta, a dimensão interna do ventrículo esquerdo na diástole e na sístole, a espessura do septo interventricular na diástole e na sístole, e a espessura da parede posterior do ventrículo esquerdo na diástole e na sístole correlacionaram-se com o peso corporal. As demais variáveis do modo-M não se correlacionaram com peso corporal, sexo ou idade. Os valores ecocardiográficos obtidos neste estudo podem ser utilizados como referência para cães dessa raça.(AU)


The aim of this study was to establish the normal echocardiographic parameters in M-mode for Yorkshire Terrier dogs. Thirty clinically normal dogs with mean weight of 2.42±0.64kg and ages varying from one to six years old were studied. The left atrial diameter, the aortic diameter, the left ventricular internal dimension at end - diastole and end - systole, end - diastolic and end - systolic interventricular septal thickness, and end - diastolic and end - systolic left ventricular posterior wall thickness had correlation with body weight. The other M - mode variables showed no linear correlations with body weight, sex or age. The echocardiographic values found in this study can be used as reference for this breed.(AU)


Asunto(s)
Animales , Perros , Perros , Corazón/anatomía & histología , Ultrasonografía/veterinaria , Estándares de Referencia , Radiografía Torácica/veterinaria , Tórax/anatomía & histología , Cardiopatías/veterinaria
6.
Arq. bras. med. vet. zootec ; 61(5): 1238-1241, out. 2009. tab
Artículo en Portugués | VETINDEX | ID: vti-7483

RESUMEN

A retrospective study was carried out to evaluate echodopplercardiographic examinations of 854 dogs referred to the service of echocardiography. This work presents the frequency of the main cardiopathies according to breed, gender, and presence of echocardiographic alterations. The valvular acquired disease was the most common cardiopathy (76.7%), mainly occurring in male dogs of small breeds. The dilated cardiomyopathy was the second more diagnosed cardiovascular pathology (9.8%), and most frequently noticed in male dogs of large or giant breeds. However, Cocker Spaniel breed also presented a high prevalence for this cardiopathy.(AU)


Asunto(s)
Animales , Perros , Cardiopatías Congénitas/diagnóstico , Cardiopatías Congénitas/epidemiología , Ecocardiografía Doppler/métodos , Ultrasonografía/métodos , Brasil/epidemiología
7.
Arq. bras. med. vet. zootec ; Arq. bras. med. vet. zootec. (Online);61(5): 1238-1241, out. 2009. tab
Artículo en Portugués | LILACS | ID: lil-532041

RESUMEN

A retrospective study was carried out to evaluate echodopplercardiographic examinations of 854 dogs referred to the service of echocardiography. This work presents the frequency of the main cardiopathies according to breed, gender, and presence of echocardiographic alterations. The valvular acquired disease was the most common cardiopathy (76.7%), mainly occurring in male dogs of small breeds. The dilated cardiomyopathy was the second more diagnosed cardiovascular pathology (9.8%), and most frequently noticed in male dogs of large or giant breeds. However, Cocker Spaniel breed also presented a high prevalence for this cardiopathy.


Asunto(s)
Animales , Perros , Cardiopatías Congénitas/diagnóstico , Cardiopatías Congénitas/epidemiología , Ecocardiografía Doppler/métodos , Ultrasonografía/métodos , Brasil/epidemiología
8.
J Endocrinol ; 189(3): 681-90, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16731798

RESUMEN

Our previous work showed that tumor necrosis factor (TNF)-alpha and FasL induce apoptosis of anterior pituitary cells. To further analyze the effect of these proapoptotic factors, we infected primary cultures from rat anterior pituitary, GH3 and AtT20 cells with first-generation adenoviral vectors encoding TNF-alpha, FasL or, as a control, beta-galactosidase (beta-Gal), under the control of the human cytomegalovirus promoter. Successful expression of the encoded transgenes was determined by immunocytochemistry. Although we observed basal expression of TNF-alpha and FasL in control cultures of anterior pituitary cells, fluorescence-activated cell sorting (FACS) cell cycle analysis showed that the overexpression of TNF-alpha or FasL increases the percentage of hypodiploid lactotropes and somatotropes. Nuclear morphology and TUNEL staining revealed that the cells undergo an apoptotic death process. We detected strong immunoreactivity for TNFR1 and Fas in the somatolactotrope cell line GH3. TNF-alpha, but not FasL, was expressed in control cultures of GH3 cells. The infection of GH3 cells with adenovirus encoding TNF-alpha or FasL increased the percentages of hypodiploid and TUNEL-positive cells. TNF-alpha or FasL immunoreactivity was not observed in the corticotrope cell line AtT20. However, adenovirus encoding TNF-alpha or FasL efficiently transduced these cells and increased the percentages of hypodiploid and TUNEL-positive cells. The expression of beta-Gal was detected in all these cultures but did not affect cell viability. In conclusion, these results suggest that death signaling cascades triggered by TNF receptor 1 (TNFR1) and Fas are present in both normal and tumoral pituitary cells. Therefore, overexpression of proapoptotic factors could be a useful tool in the therapy of pituitary adenomas.


Asunto(s)
Adenoviridae/genética , Vectores Genéticos/administración & dosificación , Glicoproteínas de Membrana/genética , Adenohipófisis/citología , Neoplasias Hipofisarias/patología , Factor de Necrosis Tumoral alfa/genética , Factores de Necrosis Tumoral/genética , Animales , Apoptosis , Línea Celular Tumoral , Proteína Ligando Fas , Femenino , Citometría de Flujo , Expresión Génica , Vectores Genéticos/genética , Inmunohistoquímica/métodos , Glicoproteínas de Membrana/metabolismo , Adenohipófisis/metabolismo , Adenohipófisis/patología , Neoplasias Hipofisarias/metabolismo , Ratas , Ratas Sprague-Dawley , Ratas Wistar , Factor de Necrosis Tumoral alfa/metabolismo , Factores de Necrosis Tumoral/metabolismo
9.
Endocrinology ; 146(11): 4737-44, 2005 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-16099864

RESUMEN

The Fas/FasL system provides the major apoptotic mechanism for many cell types, participating in cell turnover in hormone-dependent tissues. In the present study, we localized both Fas and FasL in anterior pituitary cells, mainly in lactotropes and somatotropes. The percentage of anterior pituitary cells showing immunoreactivity for Fas or FasL was higher in cells from rats killed in proestrus than in diestrus. Also, the proportion of pituitary cells from ovariectomized (OVX) rats expressing Fas or FasL increased in the presence of 17beta-estradiol (10(-9) M). This steroid increased the percentage of lactotropes with immunoreactivity for Fas or FasL and the percentage of somatotropes expressing Fas. Activation of Fas by an agonist anti-Fas antibody (Mab-Fas) decreased the vi-ability-3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT assay)-of anterior pituitary cells from OVX rats cultured in the presence of 17beta-estradiol. Also, membrane-bound FasL decreased cell viability-[3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium] assay (MTS assay)-only when anterior pituitary cells from OVX rats were incubated with 17beta-estradiol. Moreover, FasL increased the percentage of hypodiploid anterior pituitary cells (flow cytometry). Mab-Fas increased the percentage of terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end-labeling (TUNEL)-positive pituitary cells and lactotropes from OVX rats only when cells were incubated in the presence of 17beta-estradiol. Also, Mab-Fas triggered apoptosis of anterior pituitary cells from rats killed at proestrus but not at diestrus. Our results show that 17beta-estradiol up-regulates the expression of the Fas/FasL system in anterior pituitary cells and increases Fas-induced apoptosis in lactotropes, suggesting that Fas-induced apoptosis could be involved in the pituitary cell renewal during the estrous cycle.


Asunto(s)
Apoptosis/fisiología , Estrógenos/fisiología , Glicoproteínas de Membrana/metabolismo , Adenohipófisis/fisiología , Prolactina/metabolismo , Factores de Necrosis Tumoral/metabolismo , Receptor fas/metabolismo , Animales , Diestro , Estradiol/farmacología , Proteína Ligando Fas , Femenino , Ovariectomía , Adenohipófisis/citología , Adenohipófisis/metabolismo , Proestro , Ratas , Ratas Wistar , Regulación hacia Arriba
10.
Endocrinology ; 146(2): 736-43, 2005 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-15528300

RESUMEN

We previously reported that TNF-alpha-induced apoptosis of lactotropes is estrogen dependent and predominant at proestrus. Here we observed that TNF-alpha (50 ng/ml) failed to induce apoptosis of anterior pituitary cells from ovariectomized rats cultured in the presence of progesterone (10(-6) m). However, progesterone blocked the apoptotic effect of TNF-alpha in anterior pituitary cells and lactotropes cultured with 17beta-estradiol (10(-9) m). In addition, 17beta-estradiol induced apoptosis of somatotropes and triggered the proapoptotic action of TNF-alpha in these cells, effects completely blocked by ICI 182 780 (10(-6) m), an estrogen receptor antagonist. Progesterone reverted the permissive effect of 17beta-estradiol on TNF-alpha-induced apoptosis of somatotropes. TNF-alpha induced apoptosis of somatotropes from rats killed at proestrus but not at diestrus. The antiprogestine ZK 98,299 (10(-6) m) completely inhibited the protective action of progesterone on TNF-alpha-induced apoptosis of anterior pituitary cells, lactotropes, and somatotropes. Although progesterone can interact with glucocorticoid receptors, dexamethasone (10(-6) m) had no effect on TNF-alpha-induced apoptosis of anterior pituitary cells, lactotropes, and somatotropes. Our results show that progesterone, by interacting with progesterone receptors, antagonizes the permissive action of estrogens on TNF-alpha-induced apoptosis of lactotropes and somatotropes. These observations suggest that the steroid milieu may modulate the apoptotic response of anterior pituitary cells during the estrous cycle.


Asunto(s)
Apoptosis/efectos de los fármacos , Estradiol/farmacología , Adenohipófisis/citología , Progesterona/farmacología , Factor de Necrosis Tumoral alfa/farmacología , Animales , Células Cultivadas , Dexametasona/farmacología , Interacciones Farmacológicas , Femenino , Glucocorticoides/farmacología , Ovariectomía , Adenohipófisis/efectos de los fármacos , Ratas , Ratas Wistar , Receptores de Progesterona/fisiología
11.
Am J Physiol Endocrinol Metab ; 287(4): E767-71, 2004 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-15172886

RESUMEN

Tissue homeostasis results from a balance between cell proliferation and cell death by apoptosis. Estradiol affects proliferation as well as apoptosis in hormone-dependent tissues. In the present study, we investigated the apoptotic response of the anterior pituitary gland to lipopolysaccharide (LPS) in cycling female rats, and the influence of estradiol in this response in ovariectomized (OVX) rats. The OVX rats were chronically estrogenized with implanted Silastic capsules containing 1 mg of 17beta-estradiol (E2). Cycling or OVX and E2-treated rats were injected with LPS (250 microg/rat ip). Apoptosis was determined by the terminal deoxynucleotidyl-mediated dUTP nick-end labeling (TUNEL) method in sections of the anterior pituitary gland and spleen. Chronic estrogenization induced apoptosis in the anterior pituitary gland. Acute endotoxemia triggered apoptosis of cells in the anterior pituitary gland of E2-treated rats but not of OVX rats. No differences were observed in the apoptotic response to LPS in spleen between OVX and E2-treated rats. The apoptotic response of the anterior pituitary to LPS was variable along the estrous cycle, being higher at proestrus than at estrus or diestrus I. Approximately 75% of the apoptotic cells were identified as lactotropes by immunofluorescence. In conclusion, our results indicate that estradiol induces apoptosis and enables the proapoptotic action of LPS in the anterior pituitary gland. Also, our study suggests that estrogens may be involved in anterior pituitary cell renewal during the estrous cycle, sensitizing lactotropes to proapoptotic stimuli.


Asunto(s)
Apoptosis/efectos de los fármacos , Estrógenos/farmacología , Adenohipófisis/citología , Animales , Endotoxemia/metabolismo , Estradiol/farmacología , Ciclo Estral/fisiología , Femenino , Etiquetado Corte-Fin in Situ , Lipopolisacáridos/farmacología , Ovariectomía , Adenohipófisis/efectos de los fármacos , Prolactina/metabolismo , Ratas , Ratas Wistar
12.
Environ Monit Assess ; 87(2): 169-95, 2003 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-12943263

RESUMEN

Governments need good information to design policies. However, in the Argentine Pampas there are neither sufficient knowledge on environmental issues, nor clear perception of environmental alterations across space and time. The general objective of this work was to provide decision makers with a scientifically sound set of indicators aiming at the assessment of current status and future trends in the rural environment of this sensitive region. As driving criteria to select indicators, we assumed that they had to be sound, simple to calculate, easy to understand, and easily applicable by decision makers. They are related closely to significant ecological structures and functions. Twelve basic indicators were identified: (1) land use, (2) fossil energy use, (3) fossil energy use efficiency, (4) nitrogen (N) balance, (5) phosphorus (P) balance, (6) nitrogen contamination risk, (7) phosphorus contamination risk, (8) pesticide contamination, (9) soil erosion risk, (10) habitat intervention, (11) changes in soil carbon stock, and (12) balance of greenhouse gases. Indicators were geographically referenced using a geographic information system (GIS). The strength of this study is not in the absolute value of environmental indicators, but rather in the conceptualization of indicator and the identification of changing patterns, gradients and trends in space and time. According to our results, we can not definitely say that agriculture in the Pampas, as a whole, tends to be sustainable or not. While some indicators tend to improve, others keep stable, and the rest worsen. The relative importance among indicators must also be considered. The indicators that showed a negative net change are key to the identification of critical problems that will require special attention in the close future.


Asunto(s)
Agricultura , Ambiente , Monitoreo del Ambiente , Sistemas de Información Geográfica , Argentina , Conservación de los Recursos Energéticos , Conservación de los Recursos Naturales , Combustibles Fósiles , Nitrógeno , Fósforo , Medición de Riesgo
13.
Life Sci ; 66(21): 2081-9, 2000 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-10823347

RESUMEN

In previous studies we demonstrated that histone preparations possess multiple effects in vivo on pituitary hormone secretion. We have now studied the specificity and signal transduction pathways involved in the prolactin (PRL)-releasing activity of histones H2A and H2B on perifused and incubated rat pituitary cells. In the perifusion experiments, freshly dispersed pituitary cells were packed into short columns and were continuously perifused with serum-free medium. The substances to be tested (stimuli) were pumped through the perifusion circuit, at the end of which perifusate fractions were collected and PRL measured by specific RIA. In the incubation studies, freshly dispersed pituitary cells were incubated in a metabolic incubator with different stimuli at different doses and for varying times. Perifusion of cells with median eminence extract (1/30), histone H2A (30 microM) or histone H2B (30 microM), generated clear PRL release responses. Cells incubated with histone H2A and H2B showed a dose- and time-dependent stimulatory effect on PRL release which, for H2A, was blocked by peptide MB-35, an 86-120 amino acid synthetic fragment of histone H2A. The polycation, poly-lys was unable to mimic the action of histones. To detect the possible signal transduction pathways involved in the response of lactotrophs to histones, cells were incubated with the calcium ionophore A23187, the calcium chelator EGTA, the intracellular phosphoinositide enhancer LiCl, the intracellular cAMP enhancers caffeine, NaF and forskolin, and the protein kinase C inhibitor, trifluoperazine (TFP). Both EGTA (or EGTA plus A23187 ionophore) and TFP were able to reduce significantly the response of lactotrophs to histones. Our results confirm previous evidence that histones may act as hypophysotropic signals. The data also suggest that calcium- and diacylglycerol-associated pathways participate in these effects.


Asunto(s)
Histonas/metabolismo , Prolactina/metabolismo , Animales , Bovinos , Femenino , Técnicas In Vitro , Ratas , Ratas Sprague-Dawley , Sistemas de Mensajero Secundario/fisiología , Transducción de Señal , Factores de Tiempo
14.
J Am Mosq Control Assoc ; 15(2): 200-12, 1999 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10412115

RESUMEN

Prosopolepis Lutz is validated as a monotypic subgenus of Wyeomyia Theobald and the type species, Weomyia confusa (Lutz), is redescribed. The description includes illustrations of the male and female genitalia, the 4th-stage larva, and the pupa. Prosopolepis flui Bonne-Wepster and Bonne is resurrected from synonymy with Wy. confusa and recognized as the senior synonym of Wyeomyia kerri del Ponte and Cerqueira. Wyeomyia flui does not belong in the subgenus Prosopolepis and remains in the genus Wyeomyia without subgeneric placement. Trichoprosopon pusillum Lutz and Nuñez-Tovar is not synonymous with Wy. confusa and is provisionally regarded as a nomen dubium within Wyeomyia. The identity of Wy. confusa is fixed by neotype selection.


Asunto(s)
Culicidae/clasificación , Animales , Culicidae/anatomía & histología , Femenino , Masculino
15.
Rev Hosp Clin Fac Med Sao Paulo ; 54(6): 209-12, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10881069

RESUMEN

The introduction and popularization of laparoscopic cholecystectomy has been accompanied with a considerable increase in perforation of gallbladder during this procedure (10% - 32%), with the occurrence of intraperitoneal bile spillage and the consequent increase in the incidence of lost gallstones (0.2% - 20%). Recently the complications associated with these stones have been documented in the literature. We report a rare complication occurring in an 81-year-old woman who underwent laparoscopic cholecystectomy and developed cutaneous fistula to the umbilicus and elimination of biliary stones through the urinary tract. During the cholecystectomy, the gall bladder was perforated, and bile and gallstones were spilled into the peritoneal cavity. Two months after the initial procedure there was exteriorization of fistula through the umbilicus, with intermittent elimination of biliary stones. After eleven months, acute urinary retention occurred due to biliary stones in the bladder, which were removed by cystoscopy. We conclude that efforts should be concentrated on avoiding the spillage of stones during the surgery, and that no rules exist for indicating a laparotomy simply to retrieve these lost gallstones.


Asunto(s)
Colecistectomía Laparoscópica/efectos adversos , Colelitiasis/cirugía , Sistema Urinario , Anciano , Anciano de 80 o más Años , Colelitiasis/complicaciones , Femenino , Vesícula Biliar/lesiones , Humanos , Cavidad Peritoneal , Ombligo , Retención Urinaria/etiología
16.
Clin Immunol Immunopathol ; 85(1): 35-9, 1997 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9325067

RESUMEN

A growing body of evidence suggests that corticotrophin releasing hormone (CRH) may exert direct modulatory effects on immune cells. In the present study we assessed the effects of its precursor molecule, proCRH, on interleukin-6 (IL-6) release by human peripheral blood mononuclear cells (MNC). Human MNC were incubated with the corresponding stimuli for 24 hr. The supernatants were collected and IL-6 measured by ELISA. Conditioned medium from CHO-K1 cells stably transfected with the recombinant plasmid pEE14/rat pre-proCRH cDNA was used as the source of proCRH. Western blot analysis of this medium, using an antibody specific for the intact precursor, showed that no proCRH degradation products were present. The proCRH had an inhibitory effect on basal and LPS-stimulated release of IL-6. These results suggest that the full length CRH precursor may possess immunomodulatory properties.


Asunto(s)
Hormona Liberadora de Corticotropina/farmacología , Interleucina-6/metabolismo , Leucocitos Mononucleares/efectos de los fármacos , Leucocitos Mononucleares/inmunología , Precursores de Proteínas/farmacología , Adyuvantes Inmunológicos/química , Adyuvantes Inmunológicos/genética , Adyuvantes Inmunológicos/farmacología , Adulto , Animales , Células CHO , Hormona Liberadora de Corticotropina/química , Hormona Liberadora de Corticotropina/genética , Cricetinae , Medios de Cultivo Condicionados , Humanos , Técnicas In Vitro , Conformación Proteica , Precursores de Proteínas/química , Precursores de Proteínas/genética , Ratas , Transfección
17.
J Auton Nerv Syst ; 64(1): 19-23, 1997 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-9188081

RESUMEN

The effect of noradrenaline (NA) injection (20 or 40 nmol) into the preoptic area (POA) on plasma glucose and insulin was studied in male and female rats. The rats were implanted with chronic jugular catheters for blood sampling and unilateral intracerebral cannulas placed just above the POA. Blood samples were taken before and at 5, 10, 15, 30 and 60 min after NA injection. As early as 5 min after NA injection, plasma glucose levels rose rapidly in both male and female rats, reaching a peak at 15 min poststimulus. NA injection into the POA caused a dose-dependent hyperglycemic response in both male and female rats, although the response was more intense and longer lasting in females than in males. However, NA injection into the POA induced an increase in plasma insulin concentration in male but not in female rats. In addition, the increase in plasma glucose induced by 40 nmol NA injection in males preceded that of insulin. Plasma levels of glucose after POA injection of NA were already significantly elevated (p < 0.01) within the first experimental interval (5 min), whereas a plasma insulin increase were first detected 15 min post injection. We conclude that, when administered locally into the POA, NA can activate the sympathetic outflow expressed by a neurally mediated hyperglycemia which is more intense in females than in males. These data demonstrate that the POA has a sexually differentiated function in the regulation of glycemia.


Asunto(s)
Glucemia/metabolismo , Área Preóptica/fisiología , Caracteres Sexuales , Animales , Femenino , Inyecciones , Insulina/sangre , Masculino , Norepinefrina/farmacología , Ratas , Ratas Wistar
18.
Physiol Behav ; 61(2): 215-20, 1997 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9035250

RESUMEN

The effect of norepinephrine (NE) injection into the medial preoptic area (MPOA) on plasma glucose was studied in freely moving male rats. The rats were implanted with chronic jugular catheters for blood sampling and with unilateral intracerebral cannulas placed just above the MPOA. Blood samples were taken immediately before and 5, 10, 15, and 30 min after NE injection. As early as 5 min after NE injection, plasma glucose levels rose rapidly, reaching a peak at 15 min poststimulus. The hyperglycemic response to NE injection into the MPOA was dose-related within the range of doses tested (10, 20, and 40 nmol). Previous administration of phentolamine (50 nmol), but not propranolol (100 nmol), into the MPOA blocked the hyperglycemic response to NE injection into the MPOA. The increase of plasma glucose induced by NE into the MPOA and the blockade of the hyperglycemic response to NE by phentolamine suggest the involvement of an alpha-adrenergic mechanism in MPOA-mediated hyperglycemia. On the basis of these and previous results, we propose that MPOA alpha-adrenergic synapses relay impulses activating the sympathetic outflow expressed by neurally mediated hyperglycemia.


Asunto(s)
Glucemia/metabolismo , Área Preóptica/fisiología , Fibras Adrenérgicas/efectos de los fármacos , Fibras Adrenérgicas/fisiología , Antagonistas Adrenérgicos alfa/farmacología , Antagonistas Adrenérgicos beta/farmacología , Vías Aferentes/efectos de los fármacos , Vías Aferentes/fisiología , Animales , Femenino , Homeostasis/efectos de los fármacos , Homeostasis/fisiología , Masculino , Norepinefrina/farmacología , Fentolamina/farmacología , Área Preóptica/efectos de los fármacos , Propranolol/farmacología , Ratas , Ratas Wistar
20.
Medicina (B Aires) ; 53(2): 108-12, 1993.
Artículo en Inglés | MEDLINE | ID: mdl-8295525

RESUMEN

A number of thymic preparations are known to stimulate corticotropin (ACTH) release from pituitary cells but it remains unclear whether this effect is mediated by the corticotropin-releasing hormone (CRH) receptor-associated pathway. We report here that thymosin fraction five (TF5), peptide MB-35 and possibly calf thymus histones can stimulate the release of ACTH from a CRH-insensitive variant of the mouse corticotropic cell line AtT20. The effective concentration range at which TF5 and MB-35 displayed their ACTH-releasing activity in a dose-dependent manner was 100 to 2,000 micrograms/ml and 10 to 100 ng/ml, respectively, whereas neither preparation induced a significant depletion of intracellular ACTH stores. Our data suggest that thymosin peptides can stimulate ACTH release from corticotrophs by a CRH receptor-independent mechanism.


Asunto(s)
Hormona Adrenocorticotrópica/metabolismo , Hormona Liberadora de Corticotropina/metabolismo , Oligopéptidos/farmacología , Péptidos/farmacología , Timosina/análogos & derivados , Timosina/farmacología , Neoplasias del Timo/metabolismo , Análisis de Varianza , Animales , Ensayo Inmunorradiométrico , Péptidos y Proteínas de Señalización Intercelular , Ratones , Células Tumorales Cultivadas/metabolismo
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