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3.
Vascul Pharmacol ; 117: 27-34, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30326265

RESUMO

Fetal stress increases the susceptibility to cardiovascular diseases in adult age, including hypertension, a process known as fetal programming of hypertension (FPH). This study intends to investigate the interplay between vascular sympathetic nervous system (SNS) and RAS, namely the neuromodulatory role exerted by Angiotensin II (Ang II) receptor-1 (AT1) in FPH, and respective contribution for hypertension. METHODS: 6-month old Sprague-Dawley offspring from mothers fed ad-libitum (CONTROL) or with 50% intake during the second half of gestation (maternal undernutrition, MUN) were used. Sympathetic neurotransmission was studied in mesenteric/tail arteries and mesenteric veins by electrically-evoked [3H]-noradrenaline release experiments using RAS drugs. AT1 receptors in sympathetic nerves of mesenteric arteries were investigated by immunohistochemistry and Laser Scanning Confocal Microscopy. RESULTS: Ang II facilitated noradrenaline release in the vessels studied from MUN and CONTROL rats. Losartan induced a tonic facilitation only in MUN vessels. Sympathetic innervation was larger in MUN versus CONTROL vessels. AT1 receptors on sympathetic nerves were present in higher amounts in MUN versus CONTROL vessels. CONCLUSIONS: Findings support that FPH is associated with a vascular hyper-sympathetic activation, involving a tonic facilitation of prejunctional AT1 receptors by endogenous Ang II, which can justify, at least in part, the development of hypertension.


Assuntos
Pressão Arterial , Hipertensão/etiologia , Desnutrição/complicações , Artérias Mesentéricas/inervação , Efeitos Tardios da Exposição Pré-Natal , Receptor Tipo 1 de Angiotensina/metabolismo , Sistema Renina-Angiotensina , Sistema Nervoso Simpático/metabolismo , Angiotensina II/metabolismo , Fenômenos Fisiológicos da Nutrição Animal , Animais , Modelos Animais de Doenças , Feminino , Idade Gestacional , Hipertensão/metabolismo , Hipertensão/fisiopatologia , Desnutrição/metabolismo , Desnutrição/fisiopatologia , Fenômenos Fisiológicos da Nutrição Materna , Norepinefrina/metabolismo , Gravidez , Ratos Sprague-Dawley , Transdução de Sinais , Sistema Nervoso Simpático/fisiopatologia
4.
Rev Neurol ; 66(S01): S103-S107, 2018 Mar 01.
Artigo em Espanhol | MEDLINE | ID: mdl-29516461

RESUMO

INTRODUCTION: Attention deficit hyperactivity disorder (ADHD) is one of the most prevalent neurodevelopmental disorders. Other neurodevelopmental disorders may appear as a comorbidity or mimicking ADHD itself. DEVELOPMENT: This study reviews the high prevalence of other neurodevelopmental disorders (specific learning difficulties, communication disorders, etc.) in patients with ADHD. Moreover, the possible differential diagnoses include the same neurodevelopmental disorders that can occur as a comorbidity. Based on the literature, the study evaluates the role of clinical evaluation and neuropsychology in distinguishing between comorbidity and mimicry. CONCLUSIONS: The clinical evaluation could be insufficient for the comorbid diagnosis of neurodevelopmental disorders. In these cases, a neuropsychological evaluation is generally required, since it can also offer alternative diagnostic hypotheses about the symptoms observed and may therefore be a valuable aid for the differential diagnosis.


TITLE: Neurodesarrollo y fenocopias del trastorno por deficit de atencion/hiperactividad: diagnostico diferencial.Introduccion. El trastorno por deficit de atencion/hiperactividad (TDAH) es uno de los trastornos del neurodesarrollo mas prevalentes. Otros trastornos del neurodesarrollo pueden aparecer de forma comorbida o mimetizar el propio TDAH. Desarrollo. Se revisa la elevada prevalencia de otros trastornos del neurodesarrollo (trastornos especificos del aprendizaje, trastornos de la comunicacion...) en los pacientes con TDAH. Por otro lado, entre los posibles diagnosticos diferenciales se situan los mismos trastornos del neurodesarrollo que pueden aparecer de forma comorbida. Se valorara, de acuerdo a la bibliografia, el papel de la valoracion clinica y la neuropsicologia en la distincion entre comorbilidad y mimetismo. Conclusiones. La valoracion clinica podria ser insuficiente para el diagnostico comorbido de los trastornos del neurodesarrollo. En estos casos, la valoracion neuropsicologica es generalmente necesaria; esta puede igualmente ofrecer hipotesis diagnosticas alternativas de la sintomatologia observada y, por tanto, ser util para el diagnostico diferencial.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico , Transtornos do Neurodesenvolvimento/diagnóstico , Transtorno do Deficit de Atenção com Hiperatividade/epidemiologia , Comorbidade , Diagnóstico Diferencial , Humanos , Transtornos do Neurodesenvolvimento/epidemiologia , Exame Neurológico , Testes Neuropsicológicos , Fenótipo , Prevalência , Avaliação de Sintomas
5.
Nature ; 544(7649): 202-206, 2017 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-28346938

RESUMO

Recent observations have revealed massive galactic molecular outflows that may have the physical conditions (high gas densities) required to form stars. Indeed, several recent models predict that such massive outflows may ignite star formation within the outflow itself. This star-formation mode, in which stars form with high radial velocities, could contribute to the morphological evolution of galaxies, to the evolution in size and velocity dispersion of the spheroidal component of galaxies, and would contribute to the population of high-velocity stars, which could even escape the galaxy. Such star formation could provide in situ chemical enrichment of the circumgalactic and intergalactic medium (through supernova explosions of young stars on large orbits), and some models also predict it to contribute substantially to the star-formation rate observed in distant galaxies. Although there exists observational evidence for star formation triggered by outflows or jets into their host galaxy, as a consequence of gas compression, evidence for star formation occurring within galactic outflows is still missing. Here we report spectroscopic observations that unambiguously reveal star formation occurring in a galactic outflow at a redshift of 0.0448. The inferred star-formation rate in the outflow is larger than 15 solar masses per year. Star formation may also be occurring in other galactic outflows, but may have been missed by previous observations owing to the lack of adequate diagnostics.

6.
Rev Neurol ; 64(s01): S101-S104, 2017 Feb 24.
Artigo em Espanhol | MEDLINE | ID: mdl-28256695

RESUMO

INTRODUCTION: Neurodevelopmental disorders cover a heterogeneous group of disorders such as intellectual disability, autism spectrum disorders or specific learning difficulties, among others. The neurobiological and clinical variables seem to clearly justify the recent inclusion of attention deficit hyperactivity disorder (ADHD) as a neurodevelopmental disorder in the international classifications. DEVELOPMENT: Neurodevelopmental disorders are characterised by their dimensional nature and the distribution of the different symptoms in the population. These aspects are reviewed, specifically from the perspective of the clinical features and the neuropsychology of ADHD. The dimensional symptomatic nature of ADHD contrasts with the diagnostic criteria of this disorder according to different classifications or clinical guidelines. It also contrasts with the data collected by means of different complementary examinations (scales, tests, etc.). CONCLUSIONS: It is essential to understand the clinical continuum within each neurodevelopmental disorder (including ADHD), among the different neurodevelopmental disorders, and among the neurodevelopmental disorders and normality for their research, diagnosis and management. The development of instruments that provide support for this dimensional component is equally significant.


TITLE: Trastorno por deficit de atencion/hiperactividad: perspectiva desde el neurodesarrollo.Introduccion. Los trastornos del neurodesarrollo engloban a un grupo heterogeneo de trastornos como la discapacidad intelectual, el trastorno del espectro autista o los trastornos especificos del aprendizaje, entre otros. La reciente inclusion en las clasificaciones internacionales del trastorno por deficit de atencion/hiperactividad (TDAH) dentro de los trastornos del neurodesarrollo parece claramente justificada atendiendo a variables neurobiologicas y clinicas. Desarrollo. El caracter dimensional y la distribucion de diferentes sintomas en la poblacion caracterizan a la mayoria de los trastornos del neurodesarrollo. Se revisan estos aspectos, particularmente desde la sintomatologia y neuropsicologia en el TDAH. El caracter sintomatico dimensional del TDAH contrasta con los criterios diagnosticos de este trastorno de acuerdo a diferentes clasificaciones o guias clinicas. Contrasta igualmente con los datos recogidos a traves de diferentes exploraciones complementarias (escalas, tests...). Conclusiones. El entendimiento del continuo clinico dentro de cada trastorno del neurodesarrollo (incluido el TDAH), entre los diferentes trastornos del neurodesarrollo, y entre los trastornos del neurodesarrollo y la normalidad, es esencial para la investigacion, el diagnostico y el abordaje de todos ellos. El desarrollo de instrumentos que avalen este componente dimensional es igualmente trascendental.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Transtornos do Neurodesenvolvimento , Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico , Criança , Humanos
7.
Rev Neurol ; 62 Suppl 1: S79-84, 2016.
Artigo em Espanhol | MEDLINE | ID: mdl-26922963

RESUMO

Attention deficit hyperactivity disorder (ADHD) is a heterogeneous, symptomatically complex disorder. Its cardinal symptom, the presence of dysexecutive problems, emotional dysregulation of many of them and its own comorbidity, among others, will condition its clinical expression and the dysfunction. Classifying ADHD as a 'disorder' calls for an accurate assessment of the terms 'dysfunction' or 'repercussion'. The progress made in the classification and quantification of the symptoms characterising ADHD should be applied to measuring and objectifying dysfunction. Considering dysfunction as a simple interference, however clear it may be, could lead to an overestimation of the diagnosis of this disorder. Just as its estimation is essential for a diagnosis, it is also necessary for the correct evaluation of the efficacy of the therapeutic interventions, especially in the medium and long term. Further studies are needed in this sense to appraise the efficacy of the treatments, whether pharmacological or not, in different domains (social relationship, learning, self-esteem, quality of life, accidents, etc.).


TITLE: Disfuncion en el trastorno por deficit de atencion/hiperactividad: evaluacion y respuesta al tratamiento.El trastorno por deficit de atencion/hiperactividad (TDAH) es un trastorno heterogeneo y complejo sintomaticamente. Su sintomatologia cardinal, la presencia de problemas disejecutivos, la desregulacion emocional de muchos de ellos y la propia comorbilidad, entre otros, condicionaran su expresion clinica y la disfuncion. La tipificacion del TDAH como 'trastorno' requiere una evaluacion precisa del termino 'disfuncion' o 'repercusion'. Los avances en la tipificacion y cuantificacion de la sintomatologia caracteristica del TDAH deberian trasladarse a la medicion y objetivacion de la disfuncion. La estimacion de la disfuncion como una simple interferencia, por clara que sea, podria llevar a una sobreestimacion del diagnostico de este trastorno. Del mismo modo que es ineludible su estimacion para el diagnostico, es igualmente necesaria para la correcta evaluacion de la eficacia de las intervenciones terapeuticas, especialmente a medio y largo plazo. Son necesarios estudios adicionales en este sentido para valorar la eficacia de los tratamientos, sean farmacologicos o no, en diferentes dominios (relacion social, aprendizaje, autoestima, calidad de vida, siniestralidad…).


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico , Transtorno do Deficit de Atenção com Hiperatividade/terapia , Transtorno do Deficit de Atenção com Hiperatividade/fisiopatologia , Criança , Humanos , Resultado do Tratamento
8.
J Fish Dis ; 39(7): 853-65, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26644318

RESUMO

This study looks at how low infestation loads of adult Caligus rogercresseyi and other stressors affect the physiology of Salmo salar. Experimental fish groups were with (infested) or without (control) exposure to the parasite. The parasite cohort was followed for 78 days post-infestation (dpi), and only adult lice were observed. Additional stressors were applied at 60 and 75 dpi. The analysis included measurements of fish physiology and weight. Low-level infestations by adult C. rogercresseyi for more than 50 dpi induced moderate stress in S. salar as well as a high energy demand and increased small skin mucous cells. Threshold lice loads were identified, and above those loads, a high stress response was observed. Additional stressors altered fish physiology, inducing downregulation of the cortisol response after the first stressor and upregulation after the second stressor, but infested fish responded more strongly. Parasitism by C. rogercresseyi is energetically demanding, affecting the primary and secondary responses (e.g. cortisol and glucose levels), as well as the tertiary response (fish weight).


Assuntos
Copépodes/fisiologia , Ectoparasitoses/veterinária , Doenças dos Peixes/fisiopatologia , Hidrocortisona/sangue , Salmo salar , Estresse Fisiológico , Animais , Peso Corporal , Regulação para Baixo , Ectoparasitoses/fisiopatologia , Feminino , Doenças dos Peixes/parasitologia , Hidrocortisona/genética , Masculino , Densidade Demográfica , Distribuição Aleatória
9.
Br J Pharmacol ; 172(17): 4406-18, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26075500

RESUMO

BACKGROUND AND PURPOSE: The Munich Wistar Frömter (MWF) rat strain represents an experimental model to study cardiovascular alterations under conditions of progressive albuminuria. The aim of this study was to evaluate the association between genetic predisposition to albuminuria and the development of arterial stiffness and/or vascular remodelling. EXPERIMENTAL APPROACH: Experiments were performed in mesenteric arteries from 12-week-old MWF, Wistar Kyoto (WKY) and consomic MWF-6(SHR) and MWF-8(SHR) rats in which chromosomes 6 or 8 associated with albuminuria from MWF were replaced by the respective chromosome from spontaneously hypertensive rats (SHR). KEY RESULTS: Incremental distensibility, wall stress and strain were reduced, and arterial stiffness was significantly increased in albuminuric MWF compared with WKY. Albuminuria suppression in both consomic strains was associated with lower ß-values in MWF-8(SHR) and MWF-6(SHR) compared with MWF. Moreover, elastin content was significantly lower in MWF external elastic lamina compared with WKY and both consomic strains. In addition, a reduction in arterial external and internal diameter and cross-sectional area was detected in MWF compared with WKY, thus exhibiting an inward hypotrophic remodelling. However, these alterations remained unchanged in both consomic strains. CONCLUSION AND IMPLICATIONS: These data demonstrate that albuminuria in MWF is associated with increased arterial stiffness due to a reduction of elastin content in the external elastic lamina. Moreover, inward hypotrophic remodelling in MWF is not directly associated with albuminuria. In contrast, we demonstrated that two major genetic loci affect both the development of albuminuria and arterial stiffness, thus linking albuminuria and impairment of mechanical properties of resistance arteries.


Assuntos
Albuminúria/genética , Elastina/fisiologia , Predisposição Genética para Doença/genética , Rigidez Vascular/fisiologia , Albuminúria/fisiopatologia , Animais , Masculino , Artérias Mesentéricas/fisiopatologia , Técnicas de Cultura de Órgãos , Ratos , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY , Vasoconstrição/fisiologia
10.
Physiol Res ; 64(4): 547-59, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25470520

RESUMO

Intrauterine and perinatal life are critical periods for programming of cardiometabolic diseases. However, their relative role remains controversial. We aimed to assess, at weaning, sex-dependent alterations induced by fetal or postnatal nutritional interventions on key organs for metabolic and cardiovascular control. Fetal undernutrition was induced by dam food restriction (50 % from mid-gestation to delivery) returning to ad libitum throughout lactation (Maternal Undernutrition, MUN, 12 pups/litter). Postnatal overfeeding (POF) was induced by litter size reduction from normally fed dams (4 pups/litter). Compared to control, female and male MUN offspring exhibited: 1) low birth weight and accelerated growth, reaching similar weight and tibial length by weaning, 2) increased glycemia, liver and white fat weights; 3) increased ventricular weight and tendency to reduced kidney weight (males only). Female and male POF offspring showed: 1) accelerated growth; 2) increased glycemia, liver and white fat weights; 3) unchanged heart and kidney weights. In conclusion, postnatal accelerated growth, with or without fetal undernutrition, induces early alterations relevant for metabolic disease programming, while fetal undernutrition is required for heart abnormalities. The progression of cardiac alterations and their role on hypertension development needs to be evaluated. The similarities between sexes in pre-pubertal rats suggest a role of sex-hormones in female protection against programming.


Assuntos
Tecido Adiposo/crescimento & desenvolvimento , Peso Corporal , Transtornos da Nutrição Fetal/fisiopatologia , Transtornos da Nutrição do Lactente/fisiopatologia , Tamanho do Órgão , Vísceras/crescimento & desenvolvimento , Tecido Adiposo/patologia , Animais , Animais Recém-Nascidos , Feminino , Humanos , Recém-Nascido , Masculino , Gravidez , Prenhez , Ratos , Ratos Sprague-Dawley , Caracteres Sexuais , Vísceras/patologia
11.
Pediatr. aten. prim ; 15(59): e93-e96, jul.-sept. 2013. ilus
Artigo em Espanhol | IBECS | ID: ibc-115832

RESUMO

La hipertrofia de labios menores es una patología poco frecuente, que puede presentarse a cualquier edad, si bien es más frecuente su detección durante la pubertad. Se trata de una variante anatómica cuya etiología aún es incierta, que se describe como el tejido protuberante localizado tras los labios mayores. Actualmente no existen criterios clínicos objetivos consensuados para definirla. Se trata de una entidad de carácter benigno cuya sintomatología es muy variada, abarcando desde síntomas leves tales como irritación local o problemas con la higiene local, hasta infecciones crónicas, dolor al caminar, dispareunia o problemas psicológicos y estéticos. Una sencilla exploración física desde la consulta pediátrica de Atención Primaria permitirá reconocer fácilmente esta patología, y su posterior derivación al Servicio de Ginecología para su corrección quirúrgica (AU)


Labia minora hypertrophy is an uncommon condition that can occur at any age, but is most common during puberty. It is an anatomical variant of uncertain etiology, described as protruding tissue behind labia minora. Currently there are no agreed clinical criteria to define this condition. It is a benign entity whose symptoms are very varied, ranging from mild symptoms such as local irritation or problems with local hygiene, to chronic infections, pain when walking, dyspareunia or psychological and aesthetic problems. A simple physical examination from a pediatric primary care will easily recognize this disease for the subsequent referral to the gynecology department for surgical correction (AU)


Assuntos
Humanos , Feminino , Criança , Hipertrofia/complicações , Hipertrofia/diagnóstico , Hipertrofia/terapia , Tiroxina/uso terapêutico , Alopecia/complicações , Alopecia/diagnóstico , Clitóris/lesões , Clitóris/patologia , Atenção Primária à Saúde/métodos , Atenção Primária à Saúde , Clitóris
12.
J Endocrinol ; 197(1): 55-64, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18372232

RESUMO

Recent studies have demonstrated that the rat adipose tissue expresses some of the components necessary for the production of angiotensin II (Ang II) and the receptors mediating its actions. The aim of this work is to characterize the expression of the renin-angiotensin system (RAS) components in perivascular adipose tissue and to assess differences in the expression pattern depending on the vascular bed and type of adipose tissue. We analyzed Ang I and Ang II levels as well as mRNA levels of RAS components by a quantitative RT-PCR method in periaortic (PAT) and mesenteric adipose tissue (MAT) of 3-month-old male Wistar-Kyoto rats. PAT was identified as brown adipose tissue expressing uncoupling protein-1 (UCP-1). It had smaller adipocytes than those from MAT, which was identified as white adipose tissue. All RAS components, except renin, were detected in both PAT and MAT. Levels of expression of angiotensinogen, Ang-converting enzyme (ACE), and ACE2 were similar between PAT and MAT. Renin receptor expression was five times higher, whereas expression of chymase, AT(1a), and AT(2) receptors were significantly lower in PAT compared with MAT respectively. In addition, three isoforms of the AT(1a) receptor were found in perivascular adipose tissue. The AT(1b) receptor was found at very a low expression level. Ang II levels were higher in MAT with no differences between tissues in Ang I. The results show that the RAS is differentially expressed in white and brown perivascular adipose tissues implicating a different role for the system depending on the vascular bed and the type of adipose tissue.


Assuntos
Tecido Adiposo Marrom/química , Tecido Adiposo Branco/química , Sistema Renina-Angiotensina , Angiotensina I/análise , Angiotensina II/análise , Animais , Canais Iônicos/análise , Masculino , Proteínas Mitocondriais/análise , Peptidil Dipeptidase A/análise , Peptidil Dipeptidase A/genética , RNA Mensageiro/análise , Ratos , Ratos Endogâmicos WKY , Receptor Tipo 2 de Angiotensina/análise , Receptor Tipo 2 de Angiotensina/genética , Receptores de Superfície Celular/análise , Receptores de Superfície Celular/genética , Proteína Desacopladora 1 , Receptor de Pró-Renina
13.
BJU Int ; 89(7): 671-80, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-11966623

RESUMO

OBJECTIVES: To determine the efficacy of a three-fold reduced dose (RD, 27 mg) of intravesical bacille Calmette-Guérin (BCG) against the standard dose (81 mg) in patients with superficial bladder cancer, assessing recurrence, progression and differences in toxicity. PATIENTS AND METHODS: Five hundred patients with superficial bladder cancer (Ta, T1, Tis) were enrolled and randomly assigned to be treated after transurethral resection of all visible lesions with intravesical BCG Connaught strain (weekly x six and thereafter fortnightly x six) either with the standard or RD instillation. RESULTS: All but one of the 500 patients were evaluable for efficacy and toxicity (252 in the standard arm and 247 in the RD arm). The median follow-up was 69 months (maximum 104); 71 (28%) patients in the standard arm and 76 (31%) in the RD arm developed recurrences; the median time to recurrence has not yet been attained, but at 5 years the mean (sd) percentage of recurrence-free patients was 70.5 (3.12) and 70.4 (3.1) for the standard and RD arms, respectively. In patients presenting with multifocal tumours, the standard dose was more effective against recurrences than the RD (P=0.0151). In those with G3 and high-risk tumours overall, the superiority of the standard dose was marginal (P=0.060 and P=0.082). Twenty-nine (11.5%) tumours in the standard arm and 33 (13.3%) in the RD arm progressed to invasive disease; the median time to progression has not yet been attained, but the percentage of progression-free patients at 5 years was 88.8 (2.23) and 86.9 (2.31) for the standard and RD arms, respectively. The standard dose was more effective than the RD against progression only in patients with multifocal disease (P=0.048). Twelve (4.8%) cystectomies were performed in the standard and 15 (6.1%) in the RD arm. Currently, 106 (21.2%) patients have died, but only 38 (7.6%) from bladder cancer, i.e. 20 (7.9%) in the standard and 18 (7.5%) in RD arm. Overall the disease-specific death rate was lower for those patients who completed the scheduled treatment. The cause-specific survival at 5 years did not differ between the arms (P=0.76) but there was a trend toward better cause-specific survival for patients with multifocal tumours in the standard arm. Toxicity differed between the arms, significantly more patients having no toxicity in the RD arm, and fewer having delayed instillations or withdrawing. However, severe systemic toxicity occurred even in patients treated with the RD, in a similar proportion to those receiving the standard dose. CONCLUSION: Overall, the RD gave similar results for recurrence and progression but with significantly less toxicity. However, patients with multifocal tumours fared better with the standard dose and there was a trend towards better recurrence rates in patients with high-risk tumours. We recommend continuing to use the standard dose for high-risk tumours, while we consider the reduced dose safe and effective for intermediate-risk lesions and for maintenance schedules.


Assuntos
Adjuvantes Imunológicos/administração & dosagem , Vacina BCG/administração & dosagem , Neoplasias da Bexiga Urinária/tratamento farmacológico , Adjuvantes Imunológicos/efeitos adversos , Administração Intravesical , Adulto , Idoso , Vacina BCG/efeitos adversos , Cistectomia/métodos , Progressão da Doença , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Recidiva Local de Neoplasia/tratamento farmacológico , Estudos Prospectivos , Fatores de Risco , Neoplasias da Bexiga Urinária/cirurgia
14.
Hypertension ; 38(5): 1167-71, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11711516

RESUMO

We have previously reported an adaptation of arterial wall elasticity in spontaneously hypertensive rats (SHR) that involves an increase in both fibronectin/alpha5beta1-integrin complexes and smooth-muscle elastic lamellae connections. We examined the mechanical strength (MS) of the carotid artery in relation to its elastic properties, its elastin/collagen content, and the structure of the internal elastic lamina. MS was defined as the in vitro intraluminal pressure and wall stress that produces rupture of the vascular wall. Intact carotid arteries from 3-month-old normotensive rats (Wistar-Kyoto, WKY) and SHR were cannulated on a specially designed device and adjusted to their in situ length. A slowly increasing static pressure was applied until wall rupture occurred to determine the static mechanical behavior and MS. Static elasticity was similar in SHR and WKY, as were the rupture pressure (2740+/-90 versus 2740+/-40 mm Hg) and wall stress at rupture (11.5+/-1.0 versus 12.8+/-0.4 MPa), indicating equivalent MS in both groups. Histological examination showed several wall ruptures and dissociation of lamellar units that did not differ significantly between the 2 groups. Confocal microscopy showed that the size of fenestrations of the internal elastic lamina and the fraction of area occupied by them were reduced 3-fold in SHR. We have demonstrated that static elasticity of the arterial wall and mechanical strength are similar in carotid arteries from SHR and WKY.


Assuntos
Artérias Carótidas/fisiopatologia , Hipertensão/fisiopatologia , Animais , Artérias Carótidas/química , Artérias Carótidas/patologia , Colágeno/análise , Força Compressiva , Técnicas de Cultura , Elasticidade , Elastina/análise , Hipertensão/metabolismo , Hipertensão/patologia , Masculino , Microscopia Confocal , Ratos , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY
15.
Am J Physiol Heart Circ Physiol ; 280(6): H2876-81, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11356648

RESUMO

The aim of the present study was to determine whether the adventitia of large arteries modulates vascular function. We developed a method to obtain functional vascular rings devoid of adventitia. Carotid and iliac arteries from 3-mo-old Sprague-Dawley rats were denuded from adventitia after treatment with collagenase followed by gentle peeling. Adventitia removal and integrity of the media was demonstrated by optical and confocal microscopy. Arterial rings with or without adventitia and with or without endothelium were mounted in an organ bath for isometric tension recording. Responses to 75 mM KCl or norepinephrine (0.1 nM-1 microM) were significantly reduced in segments without adventitia. Acetylcholine-induced relaxation (0.1 microM-0.1 mM) was enhanced in arteries without adventitia, whereas sodium nitroprusside-induced responses were not modified. These results demonstrate that the combination of stripping with a previous collagenase treatment allows us to obtain functional rings devoid of adventitia and that this layer plays a role in contractile capacity and in endothelium-modulated responses.


Assuntos
Endotélio Vascular/fisiologia , Músculo Liso Vascular/fisiologia , Vasoconstrição/fisiologia , Vasodilatação/fisiologia , Acetilcolina/farmacologia , Animais , Artérias Carótidas/efeitos dos fármacos , Artérias Carótidas/fisiologia , Colagenases/farmacologia , Relação Dose-Resposta a Droga , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/patologia , Artéria Ilíaca/efeitos dos fármacos , Artéria Ilíaca/fisiologia , Técnicas In Vitro , Contração Isométrica/efeitos dos fármacos , Contração Isométrica/fisiologia , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/patologia , Nitroprussiato/farmacologia , Norepinefrina/farmacologia , Cloreto de Potássio/farmacologia , Ratos , Ratos Sprague-Dawley , Vasoconstrição/efeitos dos fármacos , Vasoconstritores/farmacologia , Vasodilatação/efeitos dos fármacos , Vasodilatadores/farmacologia
16.
Hypertension ; 37(4): 1101-7, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11304510

RESUMO

Our aim was to determine the structural factors that determine the mechanical adaptation of the carotid arterial wall in stroke-prone hypertensive rats (SHRSP). Distensibility-pressure and elastic modulus-stress curves assessed by in vivo echo-tracking measurements indicated a reduction in arterial stiffness in 13-week-old SHRSP compared with Wistar-Kyoto rats (WKY). Elastin and collagen contents determined biochemically were not different between SHRSP and WKY. Confocal microscopy showed that the mean area of fenestrations and fraction of area occupied by fenestrations of the internal elastic lamina (IEL) were smaller in SHRSP than in WKY, which indicated a reduction in stress-concentration effects within the IEL. Immunohistologic staining of EIIIA fibronectin isoform and total fibronectin (also as determined by Western blot) was greater in SHRSP, which suggested increased cell-matrix interactions. We suggest that these structural modifications of the vascular wall play a synergistic role in the mechanical adaptation to a high level of stress in SHRSP.


Assuntos
Artérias Carótidas/patologia , Artérias Carótidas/fisiopatologia , Hipertensão/patologia , Hipertensão/fisiopatologia , Acidente Vascular Cerebral/etiologia , Animais , Western Blotting , Artérias Carótidas/metabolismo , Colágeno/metabolismo , Elasticidade , Elastina/metabolismo , Fibronectinas/metabolismo , Hipertensão/metabolismo , Técnicas Imunoenzimáticas , Microscopia Confocal , Ratos , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY , Estresse Mecânico
17.
Astrophys J ; 533(1): L9-L12, 2000 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-10727379

RESUMO

Integral field optical spectroscopy with the INTEGRAL fiber-fed system and Hubble Space Telescope optical imaging are used to map the complex stellar and warm ionized gas structure in the ultraluminous infrared galaxy IRAS 12112+0305. Images reconstructed from wavelength-delimited extractions of the integral field spectra reveal that the observed ionized gas distribution is decoupled from the stellar main body of the galaxy, with the dominant continuum and emission-line regions separated by projected distances of up to 7.5 kpc. The two optical nuclei are detected as apparently faint emission-line regions, and their optical properties are consistent with being dust-enshrouded weak [O i] LINERs. The brightest emission-line region is associated with a faint (mI=20.4), giant H ii region of 600 pc diameter, in which a young ( approximately 5 Myr) massive cluster of about 2x107 M middle dot in circle dominates the ionization. Internal reddening toward the line-emitting regions and the optical nuclei ranges from 1 to 8 mag in the visual. Taking the reddening into account, the overall star formation in IRAS 12112+0305 is dominated by starbursts associated with the two nuclei and corresponds to a star formation rate of 80 M middle dot in circle yr-1.

18.
Astrophys J ; 527(1): L13-L16, 1999 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-10566988

RESUMO

Integral field optical spectroscopy with the INTEGRAL fiber-based system is used to map the extended ionized regions and gas flows in Mrk 273, one of the closest ultraluminous infrared galaxies. The Hbeta and [O iii] lambda5007 maps show the presence of two distinct regions separated by 4&arcsec; (3.1 kpc) along position angle (P.A.) 240 degrees. The northeastern region coincides with the optical nucleus of the galaxy and shows the spectral characteristics of LINERs. The southwestern region is dominated by [O iii] emission and is classified as a Seyfert 2. Therefore, in the optical, Mrk 273 is an ultraluminous infrared galaxy with a LINER nucleus and an extended off-nucleus Seyfert 2 nebula. The kinematics of the [O iii] ionized gas shows (1) the presence of highly disturbed gas in the regions around the LINER nucleus, (2) a high-velocity gas flow with a peak-to-peak amplitude of 2.4x103 km s-1, and (3) quiescent gas in the outer regions (at 3 kpc). We hypothesize that the high-velocity flow is the starburst-driven superwind generated in an optically obscured nuclear starburst and that the quiescent gas is directly ionized by a nuclear source, similar to the ionization cones typically seen in Seyfert galaxies.

19.
Methods Enzymol ; 307: 246-73, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10506978

RESUMO

The introduction of myographs was crucial for the study of structure and function of resistance arteries. The ability to support and maintain small blood vessels paved the way for true microscopic studies of the vascular cells. However, even after decades of study, we still do not know very much about the "normal" arrangement of smooth muscle cells in the vascular wall and how their distribution affects function. It was clearly time for the next technological step forward. We have shown here how the combination of myography and confocal microscopy creates a platform for the study of vascular structure at the cellular level and in 3D. In addition, the possibility of using live myograph-mounted vessels in combination with LSCM opens a new field of research to assess vascular remodeling from a physiological point of view and to study vascular function at a level not achieved by any other method at present. Now that the hardware is in place it is time to concentrate on the software and improve the methods of analysis. We have used 2D analysis of 3D data sets to describe differences in vascular structure and, at the same time, developed methods to semiautomate the process. The success of the 3D methods will ultimately depend on the reliability and accuracy of the analysis routines. There are still problems to overcome en route to finding a complete solution. However, we believe that the search for a robust fully (or semi-) automated method of 3D analysis will be more than worthwhile. We have defined vascular remodeling to include any changes in cellular arrangement or morphology. However, on a more subtle level, changes in receptors, enzymes, and proteins leading to altered functionality could also be regarded as remodeling. In that respect it may be interesting to map the distribution of the many receptors, channels, and proteins that regulate vascular growth, death, and function. Currently, there is a growing list of fluorescent ligands and antibodies that can be used in conjunction with confocal microscopy. It is possible that multiple stains could be used and imaged at different wavelengths with a view to constructing full 3D models of various structures and their colocalization. It is our belief that the confocal approach will prove to be a major tool in unraveling the complexities of cell-cell interactions and arrangements and will allow a better understanding of the process of vascular remodeling and function.


Assuntos
Artérias/anatomia & histologia , Microscopia Confocal/métodos , Animais , Artérias/citologia , Núcleo Celular/ultraestrutura , Células Cultivadas , Fluoresceínas , Corantes Fluorescentes , Histocitoquímica , Processamento de Imagem Assistida por Computador , Músculo Liso Vascular/citologia , Miografia/métodos , Pressão , Propídio , Coelhos , Ratos , Fixação de Tecidos
20.
J Cereb Blood Flow Metab ; 19(5): 517-27, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10326719

RESUMO

The stroke-prone spontaneously hypertensive rat (SHRSP) is a strain with high incidence of cerebrovascular accidents increased by salt-rich diet and decreased by calcium-antagonist treatment. In the SHRSP rat basilar artery the authors have previously shown reduced contractility and altered structure including regions of smooth muscle cell (SMC) disorganization. The aims of this study have been to analyze (1) the morphology of these abnormal regions, (2) the structural modifications responsible for the reduced function, and (3) the effect of salt and calcium-antagonist treatment on vascular structure and function. Wistar Kyoto and SHRSP rats, untreated or treated from week 8 through 14 with 1% NaCl or 1% NaCl + 1 mg x kg(-1) x d(-1) lacidipine, were used. Function was studied with wire myography. Structure was analyzed in fixed intact arteries with confocal microscopy. Basilar arteries from SHRSP rat showed (1) reduced contractility, (2) discrete foci of SMC disarray with altered proportion of adventitia to SMC, and (3) decreased SMC and increased adventitial cell number. Arteries from salt-loaded SHRSP rats showed a higher degree of SMC disarray and further reduction in contractility. Lacidipine treatment of salt-loaded rats significantly improved structure and function. These data suggest that vascular remodeling can provide an explanation for the observed reduction in vascular contractility of SHRSP rat basilar arteries and might show light on the effects of salt load and calcium-channel blockers in life span and the incidence of cerebrovascular accidents in SHRSP rats.


Assuntos
Artéria Basilar/patologia , Bloqueadores dos Canais de Cálcio/uso terapêutico , Hipertensão/complicações , Cloreto de Sódio na Dieta/efeitos adversos , Animais , Anti-Hipertensivos/uso terapêutico , Transtornos Cerebrovasculares/genética , Di-Hidropiridinas/uso terapêutico , Predisposição Genética para Doença , Microscopia Confocal , Ratos , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY
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