• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 27
  • 18
  • 6
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 1
  • 1
  • 1
  • Tagged with
  • 64
  • 18
  • 17
  • 8
  • 7
  • 6
  • 6
  • 5
  • 5
  • 5
  • 5
  • 5
  • 4
  • 4
  • 4
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Queilite glandular: estudo de 22 casos com análise clínico-patológica e da expressão das aquaporinas / Cheilitis glandularis: clinicopathological study of 22 patients and analysis of aquaporins expression

Melo, Juliana Nakano de 26 August 2011 (has links)
Introdução: A queilite glandular (QG) é uma doença inflamatória rara, de causa desconhecida, que afeta as glândulas salivares menores, principalmente do lábio inferior. Há secreção de saliva espessa através das glândulas salivares alteradas, causando desconforto ao doente. O quadro clínico consiste em graus variáveis de macroqueilia, acompanhada pela presença de ostíolos dilatados de glândulas salivares menores no vermilião. À expressão, há saída de material espesso e mucóide, que geralmente adere ao lábio acometido. A palpação cuidadosa pode revelar a presença de áreas nodulares endurecidas, que raramente podem supurar e drenar material purulento. O lábio inferior é o mais frequentemente acometido, e a doença tende a ser crônica e de difícil manejo. As opções terapêuticas incluem uso de corticóides tópicos ou intralesionais, antibioticoterapia oral, fotoproteção e cirurgia. A queilite glandular é considerada por alguns autores como uma condição pré-maligna, com alguns relatos de desenvolvimento de carcinoma epidermóide no lábio acometido. Aquaporinas são proteínas transmembrana que possuem a capacidade de transportar água entre os meios extra e intracelular. Desempenham, dessa maneira, papel importante na homeostase corporal. São proteínas amplamente distribuídas pelos tecidos humanos, existindo mais publicações sobre sua importância na fisiopatologia renal e do sistema nervoso central, até o momento. Os estudos sobre o papel das aquaporinas nas glândulas salivares são escassos, muitos realizados apenas em animais, não em humanos. Na queilite glandular, há alteração clínica evidente da viscosidade da saliva, o que é uma das queixas mais importantes. A alteração da expressão das aquaporinas na queilite glandular poderia corroborar o achado clínico-patológico de composição da saliva nesses doentes. Objetivos: Apresentar os achados clínicos e histopatológicos de 22 doentes com diagnóstico de queilite glandular, revisar os aspectos histopatológicos, assim como as terapias utilizadas e estudar a expressão das aquaporinas nas glândulas salivares menores labiais dos doentes em relação a controles de glândulas normais. Método: Foram analisados 22 doentes com diagnóstico de QG, acompanhados no Ambulatório de Estomatologia da Divisão de Dermatologia do HCFMUSP. Todos foram avaliados quanto aos dados clínicos e demográficos. Dez dos 22 doentes foram submetidos a tratamento cirúrgico, que consistiu na vermilionectomia do lábio inferior, seguida da dissecção das glândulas salivares menores, sendo o material analisado histopatologicamente. Em sete doentes foi realizada a análise da expressão das aquaporinas nas glândulas salivares menores labiais, comparando-os a glândulas salivares normais, através da técnica de imuno-histoquímica. Resultados: Os achados clínicos e histopatológicos evidenciaram maior prevalência de QG em indivíduos de pele clara. Observaram-se graus variáveis de sialadenite crônica e alterações epiteliais nos doentes submetidos a biopsias ou a tratamento cirúrgico. Dos 22 doentes, 3 apresentaram focos de carcinoma epidermóide no lábio inferior. A análise da expressão das aquaporinas nas glândulas salivares menores labiais mostrou positividade para AQP1, AQP2, AQP4, AQP5 e AQP8, em intensidades e localizações diversas em relação aos casos controles. Conclusões: Na queilite glandular, há aumento da chance de desenvolvimento de carcinoma epidermóide do lábio. A doença parece ter origem tanto a partir de causas exógenas, como a exposição aos raios ultravioleta, como causas endógenas, fato sugerido pelo encontro de alteração na expressão das aquaporinas nas glândulas salivares menores labiais dos doentes. Na literatura, algumas aquaporinas ainda não haviam sido detectadas por imuno-histoquímica na glândula salivar menor labial humana / Background: Cheilitis glandularis (CG) is a condition of unknown cause which thick saliva is secreted from swollen minor salivary glands from the lips. The condition is considered rare; there are few published case series, and most reports refer to single cases. The clinical picture of CG consists of variable degrees of macrocheilia accompanied by the presence of red, dilated ostia of minor salivary glands on the vermilion area. A thick, mucoid material can be obtained from these ostia by manual expression. This viscous saliva often sticks to the vermilion causing discomfort to the patient. Changes occur more frequently on the lower lip. The condition tends to be chronic and difficult to manage. Treatments vary from topical or intra lesional steroids, oral antibiotics, sun protection and surgery. Cheilitis glandularis is frequently regarded as a \"premalignant\" condition, with a few reported cases of development of squamous cell carcinoma. Aquaporins are small membrane proteins that exhibit channel activity specific for water and small solutes. They are considered essencial for corporal homeostasis, and are widely expressed through human tissues. Until now, most aquaporins studies are based on renal and nervous system fisiopathology, with few studies on situations involving salivary glands, such as Sjögrens disease. Some of them are performed over murine models, not human salivary glands. Objectives: In cheilitis glandularis, there is clinical evidence of thick saliva, which is one of the biggest complains of affected patients. We have diagnosed CG at our Oral Diseases Clinic in what seems to be a higher frequency than usually reported. This has prompted us to study these patients and present our results. Most CG reports are about isolated cases. We performed immunohistochemistry analysis to indicate aquaporins expression in human minor salivary glands affected by CG, since there is clinically thick saliva and its production is related to the activity of aquaporin channels. Methods: Data from 22 patients with diagnosis of cheilitis glandularis, from Oral Diseases Clinic of HC-FMUSP, were reviewed. Ten of 22 patients were submitted to surgical treatment, which was the surgical removal of the lower lip. We performed, on seven patients, analysis of aquaporins expression in minor labial salivary glands, in comparison to healthy tissues, through immunohistochemistry studies. RESULTS: Clinical findings showed higher prevalence of CG on fair skinned patients. Histopathological exams revealed variable degrees of chronic sialoadenitis and epithelial changes in patients submitted to surgical treatment or biopsy. Three of them have developed epidermoid carcinoma of lower lip. Analysis of aquaporins expression showed positivity for AQP1, AQP2, AQP4, AQP5 e AQP8, that differs from normal minor labial salivary glands. Conclusions: In CG, the chance of develop labial epidermoid carcinoma is increased. It seems that exogenous and endogenous components are related to the etiology of CG, as we found different expression of aquaporins in affected glands
32

Influência das fontes de N e do déficit hídrico sobre a expressão de aquaporinas e/ou transporte de ácidos orgânicos em plantas CAM / Influence of N sources and water deficit on aquaporin expression and/or organic acids transport in CAM plants

Pereira, Paula Natália 21 October 2016 (has links)
Ao longo dos últimos anos, o metabolismo ácido das crassuláceas (CAM) tem sido bem estudado em espécies das famílias Bromeliaceae e, principalmente, Crassulaceae. Essa via fotossintética é caracterizada pelo acúmulo noturno de ácidos orgânicos dentro do vacúolo e pela fixação de CO2 durante a noite pela enzima fosfoenolpiruvato carboxilase (PEPC). No entanto, pouco se sabe sobre a preferência pela atividade da enzima ATPase ou PPiase no transporte de prótons e ácidos orgânicos no interior das vesículas do tonoplasto em espécies CAM. A fotossíntese CAM pode ser induzida em plantas caracterizadas como CAM-facultativas por diversos fatores ambientais, por exemplo, déficit hídrico, termoperíodo, salinidade e deficiência de nutrientes. Contudo, pouco tem sido discutido sobre a influência dos nutrientes na indução do CAM. Esse estudo investigou o transporte de prótons através da membrana do tonoplasto em seis espécies de bromélias CAM e duas espécies de Kalanchoë. Todas as espécies usadas nesse estudo mostrou uma preferência pela ATPase do que pela PPiase para o transporte de prótons e ácidos orgânicos no interior das vesículas do tonoplasto. Nós também observamos uma maior expressão do CAM nas plantas de Kalanchoë laxiflora e Kalanchoë tubiflora mantidas na presença de 2.5 mM de NO3-. Por outro lado, Guzmania monostachia, uma espécie de bromélia epífita, exibiu a maior intensidade do CAM nas folhas mantidas na presença de NH4+ + déficit hídrico. Nessa espécie de bromélia, a maior expressão do gene ALMT9 na porção apical das folhas, seguido pelas maiores taxas de transporte de prótons pela ATPase, acúmulo de açucares solúveis e a ativação das defesas antioxidantes parecem estar relacionados com o aumento da tolerância pelo ajuste osmótico e limitação do dano oxidativo nas folhas mantidas na presença de NH4+ + déficit hídrico. Uma outra explicação para a maior intensidade do CAM no ápice das folhas mantidas em NH4+ + déficit hídrico poderia ser a maior expressão dos genes que codificam aquaporinas, principalmente GmPIPs e GmTIPs, que talvez sejam responsáveis pelo transporte de água das porções basal e mediana para a porção apical das folhas. O maior conteúdo de água conservado na porção apical poderia ajudar a aumentar a intensidade da fotossíntese CAM nessa porção das folhas de G. monostachia mantidas na presença de NH4+ + déficit hídrico / Historically, crassulacean acid metabolism (CAM) has been studied in many families, mainly Bromeliaceae and Crassulaceae. This photosynthetic pathway is characterized by the nocturnal organic acid accumulation in the vacuole as well as CO2 fixation during the night by the phosphoenolpyruvate carboxylase enzyme (PEPC). However, little is known about the preference of ATPase or PPiase activities for the proton and organic acids transport in tonoplast vesicles in CAM species. CAM photosynthesis can be inducted in CAM-facultative species by environmental factors such as, water deficit, thermoperiod, salinity and nutrients deficiency. Although, little has been discussed about the influence of nutrients on CAM induction. This study investigated proton transport in CAM bromeliad species and two CAM Kalanchoë species. All of the species used in this study showed a preference for ATPase rather than PPiase for the proton and organic acids transport into the tonoplast vesicles. We also observed a higher CAM expression in Kalanchoë laxiflora and Kalanchoë tubiflora plants kept in the presence of 2.5 mM of NO3-. On the other hand, Guzmania monostachia plants, an epiphytic tank bromeliad species, exhibited the highest CAM intensity in the leaves kept in the presence of NH4+ + water deficit. In this same bromeliad, a malate transporter gene, ALMT9, showed its highest expression in the apical portion of the leaves and the highest proton transport rates into the vacuole by ATPase. Soluble sugars and antioxidant enzymes activities were also verified in this study in order to observe their influence on increasing the drought tolerance of G. monostachia. In the leaves kept in NH4+ + water deficit the highest antioxidant activities and accumulation of soluble sugars were observed, this suggests that this inorganic nitrogen source seems to increase the drought tolerance by osmotic adjustment and limitation of oxidative damage. These factors can favor the increase of CAM intensity in the leaves kept under NH4+ + water deficiency. Another explanation for why the highest CAM intensity was observed in the apical portion of the leaves kept in NH4+ + water deficiency is because of the higher expression of aquaporin genes in the basal and middle regions of the leaves in the presence of this N source, mainly GmPIP and GmTIP, which might be responsible for transporting water from the basal and middle portions to the apical portion where these AQP genes are repressed. The fact that the highest water content is conserved in the apical portion might help to explain the increase in the intensity of CAM photosynthesis observed in the leaves of G. monostachia kept in the presence of NH4+ + water deficit
33

Effects of cortisol, vasotocin and salinity on the expression of aquaporin-1 in silver sea bream Sparus sarba. / CUHK electronic theses & dissertations collection

January 2010 (has links)
In the second part of our study, cDNA of AQP-1 and pro-vasotocin were cloned from the silver sea bream. An AQP-1 full clone was isolated from kidney and intestine and it consists of 904 bp with an open reading frame of 774 bp. The deduced amino sequence of sea bream AQP-1 shares highest identity with AQP-1a of gilthead sea bream (97.7%) and AQP-1a of other fish species (83.6% to 95.8%), however, considerably low identity was found between the silver sea bream AQP-1 and AQP-1b of gilthead sea bream (56%). The silver sea bream AQP-1 possesses basic features of a functional aquaporin and AQP-1, which includes two channel-forming asparagine-proline-alanine (NPA) signature motifs, six transmembrane domains, residues of the pore-forming region and a potential mercurial inhibiting site (Cys-178). The water channel was ubiquitously expressed in gills, liver, intestine, rectum, kidney, heart, urinary bladder and blood cells. A partial fragment of pro-vasotocin was isolated from hypothalamus of silver sea bream and consists of 184 bp, including encoding regions for the processing and amidation signal, vasotocin hormone and part of the neurophysin. / Lastly, single doses of cortisol (50 microg/g tissue) or vasotocin (1 microg/g tissue) were administered to seawater-acclimated sea bream with further three-day stabilizing period in seawater followed by an abrupt 6‰ exposure or administered to seawater transfer controls for three days. Cortisol markedly stimulated intestinal expression of AQP-1 in both the seawater transfer control and abrupt 6‰ transfer groups. Vasotocin treatment did not significantly modify AQP-1 expression in all tested organs. Hypothalamic pro-vasotocin expression levels were similar among different treatment groups. / Semi-quantitative RT-PCR analysis was used for studying the effect of salinity and hormones on expression of AQP-1 and pro-vasotocin. In the long-term salinity acclimation experiment, the sea bream were acclimated to six different salinity regimes (0‰, 6‰, 12‰, 33‰, 50‰, 70‰) for four weeks. The abundance of AQP-1 transcript was the highest in intestine of 70‰-acclimated fish among different salinity groups and there was also a statistically significant increase in 12‰-acclimated fish. Branchial AQP-1 expression was significantly upregulated in sea bream acclimated to freshwater. In contrast, the hypothalamic pro-vasotocin expression was significantly downregulated during freshwater acclimation. In addition, the sea bream were also subjected to an abrupt 6%o transfer at different time intervals (2, 6, 12, 72 and 168 hours). RT-PCR analysis revealed there was a transient decrease in branchial AQP-1 expression two hours after abrupt hypo-osmotic exposure and the expression levels subsequently returned to the seawater control levels. The expression levels of hypothalamic pro-vasotocin were not significantly altered by the abrupt exposure treatment. / The present experiments investigated the effects of salinity and hormones on the relative expression of hypothalamic pro-vasotocin, and aquaporin-1 (AQP-1) in intestine, gills and kidney of the silver sea bream Sparus sarba. With the use of immunohistochemical techniques, immunoreactivity of AQP-1 was detected at the basal side of enterocytes and gill chloride cells, and at the apical brush border of kidney tubules whereas AQP-3 was only localized in similar positions in the gills and intestines. AQP-1 was relatively more ubiquitous than AQP-3 and was localized with same cell types as the electrogenic Na+-K+-ATPase in gills and kidney. / The present study had demonstrated the responsiveness of intestinal and branchial AQP-1 expressions of the silver sea bream to environmental salinity perturbations. Further to this, cortisol was observed to upregulate the transcription of AQP-1 in the intestine. Pro-vasotocin expression was altered by long-term salinity adaptation, however, the linkage of this alteration to AQP-1 functioning in different osmoregulatory organs is yet to be elucidated. / Luk, Chun Yin. / Adviser: Norman Y. S. Woo. / Source: Dissertation Abstracts International, Volume: 72-04, Section: B, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2010. / Includes bibliographical references (leaves 200-222). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. Ann Arbor, MI : ProQuest Information and Learning Company, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.
34

Gene copy number variation in human and primate evolution /

Dumas, Laura Jane. January 2008 (has links)
Thesis (Ph.D. in Human Medical Genetics) -- University of Colorado Denver, 2008. / Typescript. Includes bibliographical references (leaves 98-112). Free to UCD Anschutz Medical Campus. Online version available via ProQuest Digital Dissertations;
35

Computational modelling of brain transport phenomena : application of multicompartmental poroelasticity

Chou, Dean January 2016 (has links)
The global population is predicted to increase to around 11 billion by 2100. By 2050, the average age in the most populous age group will be over sixty. The ageing population (over sixty-five) is projected to exceed the number of children by 2047. These demographics imply that as the ageing population section increases, there will be a greater need for long-term care services. In order to adequately prepare against this trend, medical experts and evidence-driven policymakers are realising that personalised healthcare can help alleviate the burden related to the planning and commissioning of services allied to long-term care. Central to this picture is conditions that affect the brain - the most important organ of the human body. Dementia, stroke, and other conditions have a tremendous impact on loss of life, quality of life and healthcare cost. The challenge regarding brain disease is exacerbated further due to the difficulty regarding accessibility of this organ, but also due to the immense complexity regarding its morphology and functionality. In this context, advanced biophysical modelling is considered a promising option for studying brain pathophysiology and becomes a priority investment regarding routes for brain research. Simulations offer the promise of improved, clinically relevant, predictive information, acceleration for the pipeline of drug discovery/design and better planning of long-term care for patients. Within this paradigm, a particular model of water transport in the cerebral environment is essential. Numerous brain disorders arise from water imbalance in the cerebral environment, such as hydrocephalus (HCP), oedema and Chiari malformations to name a few. In this research, a novel multiscale model of fluid regulation and tissue displacement in the cerebral environment is developed, arising from the use of Multiple-network Poroelastic Theory (MPET). Characteristics of a four-network poroelastic model (4MPET) are first explored. Then, this model is extended to a fully dynamic (transient) six-network model (6MPET) via the addition of two new compartments, namely the glial cells compartment and the glymphatic system compartment. The introduction of these two compartments in the MPET paradigm reflects recent seminal findings in cerebral physiology, namely the extent and importance regarding transport/clearance of the perivascular spaces of the brain vasculature. We develop and present a numerical implementation of the 6MPET model, and we utilise this framework to analyse acute HCP and cerebral oedema in a variety of settings, in order to show the enhanced capability of the proposed 6MPET model compared to the classical 4MPET. Investigations of acute hydrocephalus through the fully dynamic 6MPET reveal compensatory trans-ependymal pressure behaviour in the glymphatic compartment. It was also shown that aquaporin-4 (AQP4) deficient expression exaggerates ventriculomegaly, and this too is demonstrated in acute hydrocephalus. Additionally, using the 6MPET model, one is able to witness three mitigating factors for cytotoxic oedema. Specifically, these are: reducing water mobility in the glial cells compartment, increasing the compliance of the glial cells compartment and finally AQP4-deficient expression.
36

Effect of salinity and hormones on the expression of NA-K-ATPase and Aquaporin-1 in the urinary bladder of silver sea bream Sparus sarba.

January 2009 (has links)
Chau, Kai Ming. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2009. / Includes bibliographical references (leaves 136-159). / Abstract also in Chinese. / Chapter I --- Abstract --- p.i / Chapter II --- Acknowledgements --- p.vi / Chapter III --- Table of Contents --- p.vii / Chapter IV --- List of Figures --- p.xv / Chapter Chapter 1: --- Introduction --- p.1 / Chapter Chapter 2: --- Literature review --- p.7 / Chapter 2.1 --- Na+-K+ ATPase --- p.7 / Chapter 2.1.1 --- Introduction / Chapter 2.1.2 --- Structure of Na+-K+ ATPase --- p.9 / Chapter 2.1.1.2 --- Na+-K+ ATPase a subunit --- p.9 / Chapter 2.1.1.3 --- Na+-K+ ATPase β subunit --- p.11 / Chapter 2.1.1.4 --- Composition of the a subunit and β subunit --- p.12 / Chapter 2.1.1.5 --- Isomers of Na+-K+ ATPase --- p.13 / Chapter 2.1.1.6 --- Mechanism of ion exchange --- p.15 / Chapter 2.2 --- Aquaporins --- p.17 / Chapter 2.2.1 --- Introduction --- p.17 / Chapter 2.2.2 --- Structure of AQP-1 --- p.18 / Chapter 2.2.3 --- Distribution and function of AQP-1 --- p.19 / Chapter 2.3 --- Hormone --- p.22 / Chapter 2.3.1 --- Prolactin --- p.22 / Chapter 2.3.1.1 --- Structure of prolactin --- p.22 / Chapter 2.3.1.2. --- Functions of prolactin --- p.24 / Chapter 2.3.2 --- Growth hormone --- p.27 / Chapter 2.3.2.1 --- Structure --- p.27 / Chapter 2.3.2.2 --- Function of growth hormone --- p.28 / Chapter 2.3.3 --- Cortisol --- p.30 / Chapter 2.3.3.1 --- Structure --- p.30 / Chapter 2.3.3.2 --- Functions of cortisol --- p.31 / Chapter 2.4 --- Sparus sarba --- p.34 / Chapter 2.5 --- Urinary bladder of fish --- p.36 / Chapter Chapter 3: --- Effect of salinity on the expression of Na+-K+ ATPase and aquaporin-1 in the urinary bladder of silver sea bream Sparus sarba --- p.38 / Chapter 3.1 --- Introduction --- p.38 / Chapter 3.2 --- Chronic effect of salinity on the expression of Na+-K+ ATPase and aquaporin-1 in the urinary bladder --- p.40 / Chapter 3.2.1 --- Materials and Methods --- p.40 / Chapter 3.2.1.1 --- Fish --- p.40 / Chapter 3.2.1.2 --- Tissue sampling --- p.41 / Chapter 3.2.1.3 --- Protein extraction and quantification --- p.41 / Chapter 3.2.1.4 --- Na+-K+ ATPase ATPase activity --- p.42 / Chapter 3.2.1.5 --- RNA extraction and first strand cDNA synthesis --- p.43 / Chapter 3.2.1.6 --- Validation of semi-quantitative RT-PCR --- p.45 / Chapter 3.2.1.7 --- Semi-quantification of expression of Na+-K+ ATPase and aquaporin-1 in the urinary bladder --- p.47 / Chapter 3.2.1.8 --- Statistical analysis --- p.47 / Chapter 3.2.2 --- Results --- p.48 / Chapter 3.2.2.1 --- Na+-K+ ATPase activity --- p.48 / Chapter 3.2.2.2 --- Relative expression of Na+-K+ ATPase and aquaporin-1 in urinary bladder --- p.48 / Chapter 3.2.3 --- Discussion --- p.54 / Chapter 3.2.3.1 --- Chronic effect of salinity on Na+-K+ ATPase in urinary bladder --- p.54 / Chapter 3.2.3.2 --- Chronic effect of salinity on AQP-1 expression in urinary bladder --- p.59 / Chapter 3.3 --- Effect of abrupt transfer on the expression of Na+-K+ ATPase and aquaporin-1 in the urinary bladder --- p.61 / Chapter 3.3.1. --- Materials and Methods --- p.61 / Chapter 3.3.1.1 --- Fish --- p.61 / Chapter 3.3.1.2 --- Tissue sampling --- p.62 / Chapter 3.3.1.3 --- "RNA extraction, first strand cDNA synthesis and RT-PCR" --- p.62 / Chapter 3.3.1.4 --- Statistical analysis --- p.63 / Chapter 3.3.2 --- Results --- p.64 / Chapter 3.3.2.1 --- Effect of abrupt hypo-osmotic transfer on the expression of Na+-K+ ATPase and aquaporin-1 in the urinary bladder --- p.64 / Chapter 3.3.2.2 --- Effect of abrupt hyper-osmotic transfer on the expression of Na+-K+ ATPase and aquaporin-1 in the urinary bladder --- p.65 / Chapter 3.3.3 --- Discussion --- p.73 / Chapter 3.4 --- Effect of in vitro salinity on the expression of Na+-K+ ATPase and aquaporin-1 in the urinary bladder --- p.78 / Chapter 3.4.1 --- Materials and Methods --- p.78 / Chapter 3.4.1.1 --- Fish --- p.78 / Chapter 3.4.1.2 --- Tissue sampling --- p.78 / Chapter 3.4.1.3 --- Preparation of culture medium --- p.79 / Chapter 3.4.1.4 --- "RNA extraction, first strand cDNA synthesis and RT-PCR" --- p.79 / Chapter 3.4.1.5 --- Statistical analysis --- p.80 / Chapter 3.4.2 --- Results --- p.81 / Chapter 3.4.3 --- Discussion --- p.85 / Chapter 3.5 --- Conclusion --- p.86 / Chapter Chapter 4: --- Effect of hormones on the expression of Na+-K+ ATPase and aquaporin-1 in the urinary bladder of silver sea bream Sparus sarba --- p.88 / Chapter 4.1 --- Introduction --- p.88 / Chapter 4.2 --- In vivo effect of hormones on the expression of Na+-K+ ATPase and aquaporin-1 in the urinary bladder of silver sea bream Sparus sarba --- p.91 / Chapter 4.2.1 --- Material and method --- p.91 / Chapter 4.2.1.1 --- Fish --- p.91 / Chapter 4.2.1.2 --- Tissue sampling --- p.92 / Chapter 4.2.1.3 --- "RNA extraction, first strand cDNA synthesis and RT-PCR" --- p.92 / Chapter 4.2.1.4 --- Statistical analysis --- p.92 / Chapter 4.2.2 --- Results / Chapter 4.2.2.1 --- Hormonal effect on mRNA expression of Na+-K+ ATPase and AQP-1 in urinary bladder of sea water adapted fish --- p.93 / Chapter 4.2.2.2 --- Hormonal effect on mRNA expression of Na+-K+ ATPase and AQP-1 in urinary bladder of brackish water adapted fish --- p.97 / Chapter 4.2.3 --- Discussion --- p.101 / Chapter 4.2.3.1 --- Effect of prolactin on mRNA expression of Na+-K+ ATPase and AQP-1 in urinary bladder --- p.101 / Chapter 4.2.3.2 --- Effect of growth hormone on mRNA expression of Na+-K+ ATPase and AQP-1 in urinary bladder --- p.104 / Chapter 4.2.3.3 --- Effect of cortisol on mRNA expression of Na+-K+ ATPase and AQP-1 in urinary bladder --- p.106 / Chapter 4.3 --- In vitro effect of hormone on the expression of Na+-K+ ATPase and aquaporin-1 in the urinary bladder of silver sea bream Sparus sarba --- p.109 / Chapter 4.3.1 --- Materials and methods --- p.109 / Chapter 4.3.1.1 --- Fish --- p.109 / Chapter 4.3.1.2 --- Tissue sampling --- p.110 / Chapter 4.3.1.3 --- Preparation of culture medium --- p.110 / Chapter 4.3.1.4 --- "RNA extraction, first strand cDNA synthesis and RT-PCR" --- p.111 / Chapter 4.3.1.5 --- Statistical analysis --- p.111 / Chapter 4.3.2 --- Results --- p.112 / Chapter 4.3.2.1 --- Effect of prolactin on the expression of Na+-K+ ATPase and aquaporin-1 in the urinary bladder --- p.112 / Chapter 4.3.2.2 --- Effect of growth hormone on the expression of Na+-K+ ATPase and aquaporin-1 in the urinary bladder --- p.113 / Chapter 4.3.2.3 --- Effect of cortisol on the expression of Na+-K+ ATPase and aquaporin-1 in the urinary bladder --- p.123 / Chapter 4.3.3 --- Discussion --- p.124 / Chapter 4.3.3.1 --- Effect of prolactin on the expression of Na+-K+ ATPase and aquaporin-1 in the urinary bladder --- p.124 / Chapter 4.3.3.2 --- Effect of growth hormone on the expression of Na+-K+ ATPase and aquaporin-1 in the urinary bladder --- p.125 / Chapter 4.3.3.3 --- Effect of cortisol on the expression of Na+-K+ ATPase and aquaporin-1 in the urinary bladder --- p.127 / Chapter 4.4 --- Conclusion --- p.129 / Chapter Chapter 5 --- General Conclusions --- p.131 / References --- p.136
37

Caracterização fisiologica e molecular da tolerancia a seca e sua relação com o sistema radicular em especies de Coffea / Physiological and molecular characterization of drought tolerance and its relation with the root system in Coffea species

Santos, Adriana Brombini dos, 1979- 08 April 2009 (has links)
Orientador: Paulo Mazzafera / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-14T08:03:59Z (GMT). No. of bitstreams: 1 Santos_AdrianaBrombinidos_M.pdf: 1079927 bytes, checksum: 028eeeefe5616e233dd57be085df965f (MD5) Previous issue date: 2009 / Resumo: Plantas das cultivares Catuaí Vermelho e Mundo Novo de Coffea arabica L. e da cultivar Apoatã de C. canephora Pierre ex Froehner, e plantas de Mundo Novo enxertadas sobre Apoatã foram avaliadas quanto a possíveis estratégias utilizadas para suportar a baixa disponibilidade de água no solo. Em paralelo, foi conduzido um ensaio com suspensões celulares de Catuaí Vermelho sob estresse osmótico induzido por PEG. Assim, este estudo teve por objetivo examinar alguns mecanismos de tolerância à seca em café através da avaliação de aspectos morfológicos (sistema radicular), fisiológicos (ajuste osmótico) e moleculares (expressão de deidrinas e aquaporinas) em plantas jovens e cultura de células. A análise de expressão do gene CaDh1 (deidrina) em suspensão celular de café tratada com PEG (15% m/v), por 8, 24 e 72 h, mostrou aumento na atividade sob estresse osmótico, o que poderia estar associado a um possível mecanismo de proteção de membranas e macromoléculas contra a dessecação. Não foi verificada alteração na resposta dos genes PIP1, PIP2 e TIP1(aquaporinas) sob condição de estresse nas células de café. Plantas de café cultivadas em vasos (4,0 L) foram submetidas a estresse hídrico moderado por suspensão da irrigação, sob condições de casa de vegetação, até que o potencial hídrico da folha no "predawn" atingisse cerca de -2,0 MPa. Verificou-se que as taxas de crescimento nos genótipos de café arábica, avaliada pelo acúmulo de biomassa total (folhas e raízes), foram intensamente afetadas pela seca, com redução em torno de 26,5% em Catuaí e 29,0% em Mundo Novo. Por outro lado, as plantas enxertadas não apresentaram redução significativa de crescimento em relação às plantas irrigadas, sugerindo uma contribuição positiva da enxertia para melhorar a eficiência na captação de água pelo porta-enxerto Apoatã, sob condição de baixa disponibilidade de água no solo. O conteúdo de açúcares solúveis totais nas folhas das plantas irrigadas foi maior que o observado para as plantas sob déficit hídrico. A maior redução foi constatada entre os genótipos de café arábica (23,0% em Catuaí e 43,8% em Mundo Novo), enquanto as reduções em Apoatã e MN/Apoatã não foram significativas. Verificou-se maior acúmulo de aminoácidos totais nas folhas e raízes de plantas de Catuaí sob estresse hídrico comparado a Mundo Novo. Apoatã e MN/Apoatã não mostraram aumentos significativos em relação às respectivas plantas irrigadas. Em todos os genótipos analisados, os teores de prolina (Pro) nas folhas e raízes de plantas sob estresse foram aumentados e, nas raízes, esse acúmulo foi bastante acentuado, sendo 6 vezes maior nos genótipos de café arábica, 4 vezes em Apoatã e 16 vezes na enxertia MN/Apoatã em relação às plantas irrigadas. Entretanto, tais aumentos não parecem estar diretamente associados a maiores graus de tolerância à seca em café. Os conteúdos dos aminoácidos asparagina (Asn), ácido ?- aminobutírico (Gaba), glutamato (Glu) e alanina (Ala) também foram alterados, observandose, de modo geral, aumento nos teores de Asn e Gaba e redução de Glu e Ala nas folhas e raízes das plantas sob estresse. Em conclusão observou-se que os genótipos com sistema radicular mais vigoroso como Apoatã e Catuaí foram menos afetados pela seca, provavelmente porque foram mais hábeis em explorar o perfil do solo para a captação de água. / Abstract: Seedlings of the cultivars Catuaí Vermelho and Mundo Novo of Coffea arabica L., of the cultivar Apoatã of C. canephora Pierre ex Froehner, and plants of Mundo Novo grafted on Apoatã were evaluated for possible strategies to withstand low water availability in the soil. In parallel, an assay with cellular suspension culture (Catuaí Vermelho) was carried out under osmotic stress induced by PEG. Thus, this study aimed to examine morphological (root systems), physiological (osmotic adjustment) and molecular (expression of dehydrins and aquaporins) traits in coffee plants and coffee cell suspension cultures as possible mechanisms of drought tolerance. The expression analysis of CaDh1 (dehydrin) in coffee cell suspensions grown with PEG (15% w/v) for 8, 24 and 72 h, showed an increase in activity under osmotic stress indicating a possible protection mechanism against desiccation. No changes were observed in the response of PIP1, PIP2 and TIP1 genes (aquaporins) under stress condition in coffee cells. Under greenhouse conditions, coffee seedlings were cultivated in 4.0 L pots submitted to moderate drought stress by suspending irrigation until leaf water potential at predawn reach about -2.0 MPa. Among the genotypes of arabica coffee subjected to water stress there was reduction in total dry weight, around 26.5% in Catuaí and 29.0% in Mundo Novo when compared with irrigated control plants. On the other hand, the grafted plants were not affected, suggesting a positive contribution of the grafting due to bigger efficiency in the water acquisition by the rootstock Apoatã under low water availability in the soil. The content of total soluble sugars was greater in leaves of irrigated plants than plants under water stress. The greatest reduction was verified among the genotypes of arabica coffee (23.0% in Catuaí and 43.8% in Mundo Novo) while the reduction in Apoatã and MN/Apoatã was not statistically significant. The accumulation of total amino acids was higher in leaves and roots of water stressed Catuaí than Novo Mundo. Apoatã and MN/Apoatã did not show significant increase in the content of amino acids in relation to irrigated control plants. In all genotypes, water stress induced an increase in the levels of proline (Pro) in leaves and roots. In the roots this increased was about 6 times in the genotypes of arabica coffee, 4 times in Apoatã and 16 times in the grafting MN/Apoatã in relation to irrigated control plants. However this increase in the levels of Pro does not seem to be directly associated to higher degrees of drought tolerance in coffee. The content of amino acids asparagine (Asn), ?-aminobutiric acid (Gaba), glutamate (Glu) and alanine (Ala) was also changed in the leaves and roots of stressed plants. In general, there was increase in levels of Asn and Gaba while was observed reduction in content of Glu and Ala. In conclusion it was found that the genotypes with more vigorous root system as Apoatã and Catuaí were less affected by drought, probably because they were more efficient in exploring the soil profile for the water absorption. / Mestrado / Biologia Vegetal / Mestre em Biologia Vegetal
38

Expressão e localização de aquaporinas na via espermatica de cão adulto, Canis familiaris / Aquaporins expression and localization in the adult dog testis excurrent ducts (Canis familiaris)

Domeniconi, Raquel Fantin 09 August 2018 (has links)
Orientadores: Antonio Marcos Orsi, Sergio Luis Felisbino / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-09T10:45:56Z (GMT). No. of bitstreams: 1 Domeniconi_RaquelFantin_D.pdf: 10868266 bytes, checksum: 8bdfe8a912508f6afd1b6131f9f8934e (MD5) Previous issue date: 2007 / Resumo: Estudos recentes têm identificado família de proteínas denominadas aquaporinas (AQP), relacionadas à alta permeabilidade de água em várias membranas biológicas. As AQP1, AQP2, AQP7, AQP8 e AQP9 são as principais AQPs identificadas no sistema genital masculino, sendo a sua localização espécie-específica e região-específica. Em vista da importância do fluido luminal na via espermática para a integridade morfofuncional dos espermatozóides, bem como dos componentes que os constituem, tais como a água e proteínas, é importante estudar a distribuição das AQPs ao longo da via espermática. Assim, este trabalho teve como objetivos principais estudar no cão as AQP1, AQP2, AQP7, AQP8 e AQP9, visando identificá-las e localizá-las, através de imuno-histoquímica e ¿Western blotting¿ na via espermática. No cão, a AQP1 foi notada na rede testicular, ductos eferentes e em vasos, sugerindo sua importância na rápida absorção de fluido testicular. Pela primeira vez a AQP2 foi detectada na rede testicular, ductos eferentes e epidídimo, e a AQP7 no epitélio epididimário e ducto deferente em mamíferos. Porém, o papel funcional dessas AQPs no sistema genital masculino do cão permanece desconhecido. A AQP8 não foi detectada ao longo dos ductos extratesticulares do cão. A AQP9 foi abundantemente expressada ao longo da via espermática do cão, que representa um importante caminho apical para o fluxo transmembrana de água e solutos. Portanto, os resultados confirmam o padrão de expressão espécie-específica e região-específica das AQPs, sugerindo variações de atividades de absorção de fluidos e solutos ao longo da via espermática. O conhecimento destas variações torna-se relevante para estudos clínicos de infertilidade, bem como para tecnologias de reprodução assistida / Abstract: Recent studies have identified proteins called aquaporins (AQP) related to the fast water permeability in some biological membranes. AQPs are small, intrinsic membrane proteins that are present in many cell types involved in fluid transport. AQP1, AQP2, AQP7, AQP8 and AQP9 had been the main AQPs identified in the male reproductive tract, being their localization species-specific and region-specific. In view of the importance of the luminal fluid to sperm maturation and integrity of the spermatozoa, it is important to study the distribution of the AQPs throughout the spermatic way. Thus, the aim of this study was to examine the expression of AQP1, AQP2, AQP7, AQP8 e AQP9 in epithelial cells in the adult dog efferent ducts, epididymis and vas deferens, using immunohistochemistry and estern blotting methods to characterize the aquaporins in male reproductive tract. In dog, AQP1 was noted in rete testis, efferent ducts and in vessels in intertubular space, suggesting that AQP1 is important for rapid absorption of testicular fluid. For the first time the AQP2 was detected in rete testis, efferent ducts and epididymis and the AQP7 was expressed in the epithelium epididymidis and in vas deferens in mammals. But its functional role in the male dog reproductive tract, remain unknown. No specific staining for AQP8 was detected in epithelial cells of excurrent ducts in dog testis. AQP9 was abundantly expressed in dog male reproductive tract, in which it is an important apical pathway for transmembrane flow of water and neutral solutes. Thus the results confirm that the AQPs are species-specific and region-specific, suggesting activity variations related with the fluid and solute absorption throughout male excurrent ducts. Investigations of AQP biology could be relevant to clinical studies of the male reproductive tract, as well as to technologies for assisted procreation / Doutorado / Anatomia / Doutor em Biologia Celular e Estrutural
39

Queilite glandular: estudo de 22 casos com análise clínico-patológica e da expressão das aquaporinas / Cheilitis glandularis: clinicopathological study of 22 patients and analysis of aquaporins expression

Juliana Nakano de Melo 26 August 2011 (has links)
Introdução: A queilite glandular (QG) é uma doença inflamatória rara, de causa desconhecida, que afeta as glândulas salivares menores, principalmente do lábio inferior. Há secreção de saliva espessa através das glândulas salivares alteradas, causando desconforto ao doente. O quadro clínico consiste em graus variáveis de macroqueilia, acompanhada pela presença de ostíolos dilatados de glândulas salivares menores no vermilião. À expressão, há saída de material espesso e mucóide, que geralmente adere ao lábio acometido. A palpação cuidadosa pode revelar a presença de áreas nodulares endurecidas, que raramente podem supurar e drenar material purulento. O lábio inferior é o mais frequentemente acometido, e a doença tende a ser crônica e de difícil manejo. As opções terapêuticas incluem uso de corticóides tópicos ou intralesionais, antibioticoterapia oral, fotoproteção e cirurgia. A queilite glandular é considerada por alguns autores como uma condição pré-maligna, com alguns relatos de desenvolvimento de carcinoma epidermóide no lábio acometido. Aquaporinas são proteínas transmembrana que possuem a capacidade de transportar água entre os meios extra e intracelular. Desempenham, dessa maneira, papel importante na homeostase corporal. São proteínas amplamente distribuídas pelos tecidos humanos, existindo mais publicações sobre sua importância na fisiopatologia renal e do sistema nervoso central, até o momento. Os estudos sobre o papel das aquaporinas nas glândulas salivares são escassos, muitos realizados apenas em animais, não em humanos. Na queilite glandular, há alteração clínica evidente da viscosidade da saliva, o que é uma das queixas mais importantes. A alteração da expressão das aquaporinas na queilite glandular poderia corroborar o achado clínico-patológico de composição da saliva nesses doentes. Objetivos: Apresentar os achados clínicos e histopatológicos de 22 doentes com diagnóstico de queilite glandular, revisar os aspectos histopatológicos, assim como as terapias utilizadas e estudar a expressão das aquaporinas nas glândulas salivares menores labiais dos doentes em relação a controles de glândulas normais. Método: Foram analisados 22 doentes com diagnóstico de QG, acompanhados no Ambulatório de Estomatologia da Divisão de Dermatologia do HCFMUSP. Todos foram avaliados quanto aos dados clínicos e demográficos. Dez dos 22 doentes foram submetidos a tratamento cirúrgico, que consistiu na vermilionectomia do lábio inferior, seguida da dissecção das glândulas salivares menores, sendo o material analisado histopatologicamente. Em sete doentes foi realizada a análise da expressão das aquaporinas nas glândulas salivares menores labiais, comparando-os a glândulas salivares normais, através da técnica de imuno-histoquímica. Resultados: Os achados clínicos e histopatológicos evidenciaram maior prevalência de QG em indivíduos de pele clara. Observaram-se graus variáveis de sialadenite crônica e alterações epiteliais nos doentes submetidos a biopsias ou a tratamento cirúrgico. Dos 22 doentes, 3 apresentaram focos de carcinoma epidermóide no lábio inferior. A análise da expressão das aquaporinas nas glândulas salivares menores labiais mostrou positividade para AQP1, AQP2, AQP4, AQP5 e AQP8, em intensidades e localizações diversas em relação aos casos controles. Conclusões: Na queilite glandular, há aumento da chance de desenvolvimento de carcinoma epidermóide do lábio. A doença parece ter origem tanto a partir de causas exógenas, como a exposição aos raios ultravioleta, como causas endógenas, fato sugerido pelo encontro de alteração na expressão das aquaporinas nas glândulas salivares menores labiais dos doentes. Na literatura, algumas aquaporinas ainda não haviam sido detectadas por imuno-histoquímica na glândula salivar menor labial humana / Background: Cheilitis glandularis (CG) is a condition of unknown cause which thick saliva is secreted from swollen minor salivary glands from the lips. The condition is considered rare; there are few published case series, and most reports refer to single cases. The clinical picture of CG consists of variable degrees of macrocheilia accompanied by the presence of red, dilated ostia of minor salivary glands on the vermilion area. A thick, mucoid material can be obtained from these ostia by manual expression. This viscous saliva often sticks to the vermilion causing discomfort to the patient. Changes occur more frequently on the lower lip. The condition tends to be chronic and difficult to manage. Treatments vary from topical or intra lesional steroids, oral antibiotics, sun protection and surgery. Cheilitis glandularis is frequently regarded as a \"premalignant\" condition, with a few reported cases of development of squamous cell carcinoma. Aquaporins are small membrane proteins that exhibit channel activity specific for water and small solutes. They are considered essencial for corporal homeostasis, and are widely expressed through human tissues. Until now, most aquaporins studies are based on renal and nervous system fisiopathology, with few studies on situations involving salivary glands, such as Sjögrens disease. Some of them are performed over murine models, not human salivary glands. Objectives: In cheilitis glandularis, there is clinical evidence of thick saliva, which is one of the biggest complains of affected patients. We have diagnosed CG at our Oral Diseases Clinic in what seems to be a higher frequency than usually reported. This has prompted us to study these patients and present our results. Most CG reports are about isolated cases. We performed immunohistochemistry analysis to indicate aquaporins expression in human minor salivary glands affected by CG, since there is clinically thick saliva and its production is related to the activity of aquaporin channels. Methods: Data from 22 patients with diagnosis of cheilitis glandularis, from Oral Diseases Clinic of HC-FMUSP, were reviewed. Ten of 22 patients were submitted to surgical treatment, which was the surgical removal of the lower lip. We performed, on seven patients, analysis of aquaporins expression in minor labial salivary glands, in comparison to healthy tissues, through immunohistochemistry studies. RESULTS: Clinical findings showed higher prevalence of CG on fair skinned patients. Histopathological exams revealed variable degrees of chronic sialoadenitis and epithelial changes in patients submitted to surgical treatment or biopsy. Three of them have developed epidermoid carcinoma of lower lip. Analysis of aquaporins expression showed positivity for AQP1, AQP2, AQP4, AQP5 e AQP8, that differs from normal minor labial salivary glands. Conclusions: In CG, the chance of develop labial epidermoid carcinoma is increased. It seems that exogenous and endogenous components are related to the etiology of CG, as we found different expression of aquaporins in affected glands
40

Envolvimento da AQP4 no envenenamento por Phoneutria nigriventer = Involvement of AQP4 in Phoneutria nigriventer envenoming / Involvement of AQP4 in Phoneutria nigriventer envenoming

Stávale, Leila Miguel, 1985- 02 January 2013 (has links)
Orientador: Maria Alice da Cruz Höfling / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-23T19:45:28Z (GMT). No. of bitstreams: 1 Stavale_LeilaMiguel_M.pdf: 25008584 bytes, checksum: 8754f8fc3865217986eb0137679176e9 (MD5) Previous issue date: 2013 / Resumo: O veneno da aranha Phoneutria nigriventer (PNV), também conhecida como aranha armadeira, é uma mistura complexa de peptídeos com ação neurotóxica em alguns canais iônicos. No sistema nervoso central (SNC) alguns peptídeos do PNV causam permeabilização da barreira hematoencefálica (BHE) e interferem na liberação de neurotransmissores. A BHE, embora essencial para a manutenção da homeostase do SNC, pode representar uma barreira muito restritiva para o acesso de drogas terapêuticas ao microambiente neural. O entendimento dos mecanismos associados à disfunção da BHE é relevante do ponto de vista científico e médico. O objetivo do estudo foi investigar alguns mecanismos envolvidos na neurotoxicidade do veneno da Phoneutria nigriventer em ratos Wistar (Rattus norvegicus). Para esse fim, o efeito vasogênico causado pela neurotoxicidade do veneno no cérebro, foi examinado através da avaliação da expressão de aquaporina 4 (AQP4), uma proteína formadora dos canais de água e abundantemente localizada nos pés astrocitários perivasculares e relacionada com o aparecimento de edema no cérebro. A análise da expressão da proteína foi feita por imunohistoquímica e western blotting e a expressão de RNAm por PCR em tempo real no cerebelo e hipocampo de animais neonatos (14 dias) e adultos (8 semanas). Os resultados obtidos mostraram aumento da expressão de AQP4 e seu RNAm nos animais envenenados, que entretanto foi variável em função do tempo de envenenamento (2, 5 ou 24 h), da região do cerebelo ou hipocampo examinada e da idade dos animais. Os resultados mostraram também intensa marcação anti-AQP4 ao redor de vasos com edema perivascular ou não, como também entre os corpos neuronais e seus prolongamentos. Concluímos que a AQP4 tem papel nas alterações de volume dos astrócitos perivasculares e na formação e resolução do edema ao redor da BHE causado pelo PNV. A dinâmica da expressão da AQP4 no cerebelo e hipocampo em função do tempo, região e idade dos animais sugere a existência de fatores intrínsicos que modulam diferencialmente a funcionalidade da BHE em função do microambiente local. A compreensão dos mecanismos envolvidos no envenenamento por PNV pode contribuir para o desenvolvimento de ferramentas úteis para a intervenção clínica, bem como pode ser relevante para o entendimento dos mecanismos relacionados ao funcionamento da BHE e de proteínas envolvidas na formação de canais de água, como a AQP4 / Abstract: The Phoneutria nigriventer spider venom (PNV), also known as armed-spider, is a complex mixture of ion channels-acting peptides which exhibit neurotoxic action. In the central nervous system (CNS), PNV-containing peptides cause permeabilization of the blood-brain barrier (BBB) and interfere with neurotransmitter release. The BBB, although essential for the maintenance of homeostasis of the CNS, may represent a very restrictive barrier for the access of therapeutic drugs into the neural microenvironment. The understanding of BBB impairment-associated mechanisms are of scientific and medical importance. The aim of this study was to investigate some of the mechanisms involved in the neurotoxicity caused by Phoneutria nigriventer venom in Wistar rats (Rattus norvegicus). To this end, the vasogenic effect caused by the venom neurotoxicity in the brain was examined by evaluating the expression of aquaporin 4 (AQP4), a water channel forming protein abundantly expressed in perivascular astrocytic endfeet processes and associated to the formation and resolution of edema in the brain. The analysis of AQP4 expression was assessed in the cerebellum and hippocampus of neonate (14 day-old) and adult rats (8 week-old) through immunohistochemistry and western blotting, and the expression of mRNA by Real Time-PCR. The results showed increases of AQP4 expression and its mRNA in the envenomed animals, which though showed time- (2, 5 or 24h), regional- (regions of the cerebellum and hippocampus examined) and age-associated differences. Marked anti-AQP4 labeling was found around vessels with or without edema and among the neuron bodies and their processes. We conclude that AQP4 has a role in the volume alterations of the perivascular astrocytes and in the formation and resolution of edema around the BBB induced by PNV. The variability of the dynamics of AQP4 expression in the cerebellum and hippocampus in function of the time, region and animals age suggests the existence of intrinsic factors that modulate the BBB functionality depending on the molecular biology dynamics of the local microenvironment. The understanding of the mechanisms involved in the envenomation by PNV can contribute to the development of useful tools for clinical intervention, and may be relevant for understanding the mechanisms related to the functioning of the BBB and proteins involved in the formation of water channels, such as AQP4 / Mestrado / Histologia / Mestra em Biologia Celular e Estrutural

Page generated in 0.0639 seconds