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1.
Int J Comput Assist Radiol Surg ; 10(11): 1721-35, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25740204

RESUMO

PURPOSE: Recently, there has been an increasing interest in the role of deep fascia mobility in musculoskeletal dynamics and chronic pain mechanisms; however, no strategies have been presented so far to study in vivo fascial motion in 3D. This paper presents a semiautomatic method, based on ultrasound (US) imaging, enabling a 3D evaluation of fascia mobility. METHODS: The proposed approach relies on the acquisition of 3D US datasets at rest and during a voluntary muscular contraction and consists of two phases: 3D US dataset analysis and generation of a displacement vector field using a block matching technique (Phase 1) and validation and filtering of the resulting displacement vector field for outliers removal (Phase 2). The accuracy and effectiveness of the proposed method were preliminarily tested on different 3D US datasets, undergoing either simulated (procedural) or real (muscular contraction) deformations. RESULTS: As for the simulated deformation, estimated displacement vectors resulting from Phase 1 presented a mean magnitude percentage error of 8.05 % and a mean angular error of 4.78° which, after Phase 2, were reduced by 69.44 and by 83.05 %, respectively. Tests on real deformations further validated the effectiveness of Phase 2 in the removal of outliers from the displacement vector field. CONCLUSIONS: Obtained results preliminarily demonstrate the viability of the proposed algorithm for the analysis of fascia mobility. Such analysis can enable clinicians to better understand the fascia role in musculoskeletal dynamics and disorder. Further experiments are needed to optimize the method in consideration of the anatomical region to be studied.


Assuntos
Algoritmos , Fascia Lata/diagnóstico por imagem , Imageamento Tridimensional/métodos , Contração Muscular , Adulto , Fáscia/diagnóstico por imagem , Humanos , Masculino , Movimento (Física) , Ultrassonografia
2.
J Bodyw Mov Ther ; 18(4): 588-90, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25440212

RESUMO

Despite their importance in anatomy, physiology, pathology and surgery, the fasciae and the fascial spaces have been poorly described in classic textbooks. This little attention depends on the fact that these fasciae vary in thickness and composition, especially at the cervical level. Indeed, in the main literature they have been described in different forms. Furthermore, the definition itself of the fascia is not consistent in a variety of authors. As a consequence, different criteria have been used to define and classify the fascial systems. In this paper, a brief terminological history and the most common nomenclatures and classifications of the fascia have been summarized.


Assuntos
Fáscia/anatomia & histologia , Perna (Membro) , Feminino , Humanos , Masculino
3.
Stem Cell Rev Rep ; 10(3): 429-46, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24619862

RESUMO

Cryopreservation is the only method for long-term storage of viable cells and tissues used for cellular therapy, stem cell transplantation and/or tissue engineering. However, the freeze-thaw process strongly contributes to cell and tissue damage through several mechanisms, including oxidative stress, cell injury from intracellular ice formation and altered physical cellular properties. Our previous proteomics investigation was carried out on Wharton's Jelly Stem Cells (WJSCs) having similar properties to adult mesenchymal stem cells and thus representing a rich source of primitive cells to be potentially used in regenerative medicine. The aim of the present work was to investigate molecular changes that occur in WJSCs proteome in different experimental conditions: fresh primary cell culture and frozen cell. To analyze changes in protein expression of WJSCs undergoing different culturing procedures, we performed a comparative proteomic analysis (2DE followed by MALDI-TOF MS/MS nanoESI-Q-TOF MS coupled with nanoLC) between WJSCs from fresh and frozen cell culturing, respectively. Frozen WJSCs showed qualitative and quantitative changes compared to cells from fresh preparation, expressing proteins involved in replication, cellular defence mechanism and metabolism, that could ensure freeze-thaw survival. The results of this study could play a key role in elucidating possible mechanisms related to maintaining active proliferation and maximal cellular plasticity and thus making the use of WJSCs in cell therapy safe following bio-banking.


Assuntos
Criopreservação , Células-Tronco Mesenquimais , Proteoma/metabolismo , Adipogenia , Antígenos CD/metabolismo , Separação Celular , Células Cultivadas , Humanos , Osteogênese , Mapas de Interação de Proteínas , Telômero/genética , Cordão Umbilical/citologia
4.
Eur J Vasc Endovasc Surg ; 47(1): 53-60, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24183249

RESUMO

OBJECTIVES: The purpose of this in vitro study was to clinically assess the feasibility of a three-dimensional (3D) electromagnetic (EM) navigator, including sensorized catheters and guidewires, to determine any reduction in radiation dose and contrast medium injection. METHODS: The study was performed using a navigator prototype developed at the EndoCAS center. The system includes catheters and guidewires simultaneously tracked with an EM localizer (Aurora, Northern Digital, Waterloo, Canada). Tests were performed on a commercial abdominal aortic aneurysm model. Fifteen operators were asked to cannulate renal arteries using the conventional fluoroscopic guidance and the EM navigator without fluoroscopic support. Each trial was video-recorded and analyzed for timing and success of completing the cannulation task by two blinded and independent observers. Performances were also qualitatively evaluated using the Imperial College Endovascular Cannulation Scoring Tool (IC3ST). Moreover, a questionnaire was administered to participants to evaluate the navigator potentialities. RESULTS: Quantitative analysis results show no significant difference between the fluoroscopic and EM guidance regarding the total procedure time (median 2.36 minutes [interquartile range {IQR} = 1.26-4.7) vs. 2.95 min [IQR = 1.35-5.38], respectively; p = .93); number of total hits with catheter/guidewire tip to vessels wall (median 5.50 [IQR = 2.00-10.00] vs. 3.50 [IQR = 2.50-7.00], respectively; p = .65); and number of attempts at cannulation (median 4.0 [IQR = 2.00-5.00] vs. 4.0 [IQR = 2.00-5.00], respectively; p = .72]. Moreover, there was no significant difference between the IC3ST score obtained using the EM navigator and the traditional method (average 22.37 [STD = 7.95] vs. 21.58 [STD = 6.86]; p = .92). Finally, questionnaire results indicate a general agreement concerning the navigator usefulness, which clearly shows the positions of instruments inside the 3D model of the patient's anatomy. Participants also agreed that the navigator can reduce the amount of contrast media delivered to the patient, as well as fluoroscopy time. CONCLUSIONS: This work provides proof of concept that simultaneous EM navigation of guidewires and catheters is feasible without the use of live fluoroscopic images.


Assuntos
Aneurisma da Aorta Abdominal/diagnóstico por imagem , Fenômenos Eletromagnéticos , Radiografia Intervencionista , Artéria Renal/diagnóstico por imagem , Terapia Assistida por Computador , Dispositivos de Acesso Vascular , Aneurisma da Aorta Abdominal/terapia , Aortografia/métodos , Cateterismo Periférico/instrumentação , Cateterismo Periférico/métodos , Competência Clínica , Meios de Contraste , Estudos de Viabilidade , Fluoroscopia , Humanos , Modelos Anatômicos , Modelos Cardiovasculares , Doses de Radiação , Radiografia Intervencionista/métodos , Inquéritos e Questionários , Análise e Desempenho de Tarefas , Terapia Assistida por Computador/instrumentação , Terapia Assistida por Computador/métodos , Fatores de Tempo , Tomografia Computadorizada por Raios X , Gravação em Vídeo
5.
Ann N Y Acad Sci ; 1025: 162-70, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15542714

RESUMO

The monoamine neurotoxin methamphetamine (METH) is commonly used as an experimental model for Parkinson's disease (PD). In fact, METH-induced striatal dopamine (DA) loss is accompanied by damage to striatal nerve endings arising from the substantia nigra. On the other hand, PD is characterized by neuronal inclusions within nigral DA neurons. These inclusions contain alpha-synuclein, ubiquitin, and various components of a metabolic pathway named the ubiquitin-proteasome (UP) system, while mutation of genes coding for various components of the UP system is responsible for inherited forms of PD. In this presentation we demonstrate for the first time the occurrence of neuronal inclusions in vivo in the nigrostriatal system of the mouse following administration of METH. We analyzed, in vivo and in vitro, the shape and the fine structure of these neuronal bodies by using transmission electron microscopy. Immunocytochemical investigation showed that these METH-induced cytosolic inclusions stain for ubiquitin, alpha-synuclein, and UP-related molecules, thus sharing similar components with Lewy bodies occurring in PD, with an emphasis on enzymes belonging to the UP system. In line with this, blockade of this multicatalytic pathway by the selective inhibitor epoxomycin produced cell inclusions with similar features. Moreover, using a multifaceted pharmacological approach, we could demonstrate the need for endogenous DA in order to form neuronal inclusions.


Assuntos
Metanfetamina/toxicidade , Complexo de Endopeptidases do Proteassoma/ultraestrutura , Inibidores de Proteassoma , Animais , Corpo Estriado/efeitos dos fármacos , Corpo Estriado/ultraestrutura , Camundongos , Camundongos Endogâmicos C57BL , Células PC12 , Ratos , Substância Negra/efeitos dos fármacos , Substância Negra/ultraestrutura
6.
Laryngoscope ; 114(1): 118-25, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14710006

RESUMO

OBJECTIVE: To investigate whether formation of nitrotyrosine in the nasal polyps of atopic patients occurs. STUDY DESIGN: A nonrandomized, retrospective, controlled qualitative and quantitative study. METHODS: Nasal polyp tissue samples were acquired from 12 atopic patients. Control fragments of nasal mucosa were taken from 10 patients undergoing corrective surgery of the nasal septum. For routine histologic examinations, hematoxylin-eosin staining was used. Low-magnification microscopy was designed to yield pathologic characteristics and high magnification to quantify the number of eosinophils in the subepithelial connective tissue. Presence of nitrotyrosine was assessed by immunohistochemical method. RESULTS: Hematoxylin-eosin staining revealed presence of numerous eosinophils in the epithelium and in the subepithelial connective tissue. All polyps were characterized by epithelial damage. Nitrotyrosine was present in the eosinophils, in the ciliated cell, and in cells of the damaged epithelium. Goblet cells, glands, and vessels were found to be negative. No significant differences concerning the localization of nitrotyrosine were recognized among the examined nasal polyps. CONCLUSIONS: Nitrotyrosine immunohistochemical staining in nasal-polyp tissues suggested the existence of progressive epithelium injury caused by peroxynitrite. Consequences of peroxynitrite formation in eosinophils remain to be precisely established. The lack of nitrotyrosine in glands and blood vessels indicated that peroxynitrite does not have a significant role in the vascular and glandular dysfunction of nasal polyps.


Assuntos
Hipersensibilidade Imediata/metabolismo , Pólipos Nasais/química , Tirosina/análogos & derivados , Tirosina/metabolismo , Adulto , Estudos de Casos e Controles , Eosinófilos/química , Feminino , Humanos , Imuno-Histoquímica , Masculino , Mucosa Nasal/química , Mucosa Nasal/patologia , Pólipos Nasais/patologia , Ácido Peroxinitroso/metabolismo , Estudos Retrospectivos
7.
Psychopharmacology (Berl) ; 173(3-4): 353-63, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-14673567

RESUMO

RATIONALE: 3,4-Methylenedioxymethamphetamine (MDMA) is an amphetamine derivative, which is neurotoxic to both serotonin (5HT) and dopamine (DA) nerve terminals. Previous reports, carried out in rodents and non-human primates, demonstrated neurotoxicity to monoamine axon terminals, although no study has analyzed nigral and striatal cell bodies at the sub-cellular level. OBJECTIVE: In this study, we examined intrinsic nigral and striatal cells, and PC12 cell cultures to evaluate whether, in mice, MDMA might affect nigral and striatal cell bodies. METHODS: After administering MDMA, we analyzed effects induced in vivo and in vitro using high-performance liquid chromatography (HPLC) analysis, light- and electron microscopy with immunocytochemistry, and DNA comet assay. RESULTS: We found that MDMA (5 mg/kg x4, 2 h apart), besides a decrease of nigrostriatal DA innervation and 5HT loss, produces neuronal inclusions within nigral and intrinsic striatal neurons consisting of multi-layer ubiquitin-positive whorls extending to the nucleus of the cell. These fine morphological changes are associated with clustering of heat shock protein (HSP)-70 in the nucleus, very close to chromatin filaments. In the same experimental conditions, we could detect oxidation of DNA bases followed by DNA damage. The nature of inclusions was further investigated using PC12 cell cultures. CONCLUSIONS: The present findings lead to re-consideration of the neurotoxic consequences of MDMA administration. In fact, occurrence of ubiquitin-positive neuronal inclusions and DNA damage both in nigral and striatal cells sheds new light into the fine alterations induced by MDMA, also suggesting the involvement of nuclear and cytoplasmic components of the ubiquitin-proteasome pathway in MDMA toxicity.


Assuntos
Corpo Estriado/efeitos dos fármacos , Dano ao DNA , N-Metil-3,4-Metilenodioxianfetamina/toxicidade , Neurônios/metabolismo , Serotoninérgicos/toxicidade , Substância Negra/efeitos dos fármacos , Ubiquitina/metabolismo , Animais , Corpo Estriado/metabolismo , Corpo Estriado/patologia , Dopamina/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neurônios/ultraestrutura , Células PC12 , Ratos , Substância Negra/metabolismo , Substância Negra/patologia
8.
Scand J Rheumatol ; 32(5): 261-7, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-14690137

RESUMO

OBJECTIVE: In our previous work, patients affected by SSc were treated with intravenous urokinase and showed clinical improvement. In this study we used microscopy to document ultrastructural alterations occurring in sclerodermic skin from SSc patients treated with urokinase. METHODS: Ten patients with SSc were selected for this study. Skin biopsies were taken from the medial side of the right forearm on the third proximal on the volar surface. The patients were then treated with urokinase for 7 consecutive days. At the end of the treatment, the patients were examined and a new skin biopsy was taken close to the above-mentioned zone of the forearm for optic and electron microscopy examination. RESULTS: The patients showed a gradual improvement of the skin after urokinase treatment. Raynaud's appeared to be less intense, and they had an increased articular range, with the restoration of movements that had previously been limited. Histological findings showed that, after treatment, skin alterations appeared attenuated, in particular the connective tissue showed a decreased density and inflammatory infiltrate was slight. Electron microscopy findings showed that collagen fibres appeared to have a more regular diameter, and the capillary vessels' lining was thicker, with fewer pinocytotic vesicles. CONCLUSION: These observations show that urokinase treatment seems to be an interesting therapeutic strategy to consider for the treatment of SSc.


Assuntos
Ativadores de Plasminogênio/uso terapêutico , Escleroderma Sistêmico/tratamento farmacológico , Escleroderma Sistêmico/patologia , Pele/patologia , Ativador de Plasminogênio Tipo Uroquinase/uso terapêutico , Adulto , Idoso , Capilares/efeitos dos fármacos , Capilares/ultraestrutura , Colágeno/efeitos dos fármacos , Colágeno/ultraestrutura , Matriz Extracelular/efeitos dos fármacos , Matriz Extracelular/ultraestrutura , Feminino , Humanos , Injeções Intravenosas , Pessoa de Meia-Idade , Ativadores de Plasminogênio/administração & dosagem , Escleroderma Sistêmico/fisiopatologia , Pele/irrigação sanguínea , Resultado do Tratamento , Ativador de Plasminogênio Tipo Uroquinase/administração & dosagem
9.
Bioorg Med Chem Lett ; 11(23): 3023-6, 2001 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-11714602

RESUMO

New fluorescent ligands for adenosine receptors (ARs), obtained by the insertion, in the N(6) position of NECA, of NBD-moieties with linear alkyl spacers of increasing length, proved to possess a high affinity and selectivity for the A(3) subtype expressed in CHO cells. In fluorescence microscopy assays, compound 2d, the most active and selective for human A(3)-AR, permitted visualization and localization of this human receptor subtype, showing its potential suitability for internalization and trafficking studies in living cells.


Assuntos
Adenosina-5'-(N-etilcarboxamida)/química , Corantes Fluorescentes/química , Corantes Fluorescentes/metabolismo , Receptores Purinérgicos P1/metabolismo , Animais , Benzofuranos/química , Células CHO , Membrana Celular/metabolismo , Células Cultivadas , Cricetinae , Humanos , Ligantes , Microscopia de Fluorescência , Nitrocompostos/química , Receptor A2A de Adenosina , Receptor A3 de Adenosina , Receptores Purinérgicos P1/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
10.
Neuroscience ; 104(1): 15-31, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11311527

RESUMO

Recently, we described the occurrence of a dehydroascorbate reductase within the rat CNS. This enzyme regenerates ascorbate after it is oxidized during normal aerobic metabolism. In this work, we describe the neuronal compartmentalization of the enzyme, using transmission electron microscopy of those brain areas in which the enzyme was most densely present when observed under light microscopy. In parallel biochemical studies, we performed immunoblotting and measured the enzyme activity of the cytoplasm and different nuclear fractions. Given the abundance of ascorbate in the caudate-putamen, we focused mostly on the occurrence of dehydroascorbate reductase at the striatal subcellular level. We also studied cerebellar Purkinje cells, hippocampal CA3 pyramidal cells and giant neurons in the magnocellular part of the red nucleus. In addition to neurons, immunolabeling was found in striatal endothelial cells, in the basal membrane of blood vessels and in perivascular astrocytes. In neuronal cytosol, the enzyme was observed in a peri-nuclear position and on the nuclear membrane. In addition, in both the striatum and the cerebellum, we found the enzyme within myelin sheets. Dehydroascorbate reductase was also present in the nucleus of neurons, as further indicated by measuring enzyme activity and by immunoblotting selected nuclear fractions. Immunocytochemical labeling confirmed that the protein was present in isolated pure nuclear fractions. Given the great amount of free radicals which are constantly generated in the CNS, the discovery of a new enzyme with antioxidant properties which translocates into neuronal nuclei appears to be a potential starting point to develop alternative strategies in neuroprotection.


Assuntos
Ácido Ascórbico/biossíntese , Encéfalo/enzimologia , Compartimento Celular/fisiologia , Glutationa/metabolismo , Neurônios/enzimologia , Oxirredutases/metabolismo , Animais , Encéfalo/ultraestrutura , Cerebelo/metabolismo , Cerebelo/ultraestrutura , Citosol/metabolismo , Feminino , Hipocampo/metabolismo , Hipocampo/ultraestrutura , Imuno-Histoquímica , Microscopia Eletrônica , Neostriado/metabolismo , Neostriado/ultraestrutura , Neurônios/ultraestrutura , Ratos , Ratos Wistar , Núcleo Rubro/metabolismo , Núcleo Rubro/ultraestrutura , Frações Subcelulares/metabolismo , Frações Subcelulares/ultraestrutura
11.
Neurosci Biobehav Rev ; 24(6): 655-68, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10940440

RESUMO

In Parkinson's disease, together with the classic loss of dopamine neurons of the substantia nigra pars compacta, neuropathological studies and biochemical findings documented the occurrence of a concomitant significant cell death in the locus coeruleus. This review analyzes the latest data obtained from experimental parkinsonism indicating that, the loss of norepinephrine in Parkinson's disease might worsen the dopamine nigrostriatal damage. Within this latter context, basic research provided a new provocative hypothesis on the significance of locus coeruleus in conditioning the natural history of Parkinson's disease. In particular, the loss of a trophic influence of these neurons might be crucial in increasing the sensitivity of nigrostriatal dopamine axons to various neurotoxic insults. In line with this, recently, it has been shown that locus coeruleus activity plays a pivotal role in the expression of various immediate early genes and in inducing the phosphorilation of cyclic adenosine monophosphate response element-binding proteins, suggesting a role of the nucleus in sustaining a protective effect.


Assuntos
Locus Cerúleo/fisiopatologia , Doença de Parkinson/fisiopatologia , Animais , Humanos , Locus Cerúleo/metabolismo , Locus Cerúleo/patologia , Norepinefrina/metabolismo , Norepinefrina/fisiologia , Doença de Parkinson/metabolismo , Doença de Parkinson/patologia
12.
Neuroscience ; 94(3): 937-48, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10579586

RESUMO

In this study, we describe for the first time the occurrence, within the central nervous system of the rat, of a dehydroascorbate reductase analogous to the one we recently described in the liver. Dehydroascorbate reductase plays a pivotal role in regenerating ascorbic acid from its oxidation product, dehydroascorbate. In a first set of experiments, we showed that a dehydroascorbate reductase activity is present in brain cytosol; immunoblotting analysis confirmed the presence of an immunoreactive cytosolic protein in selected brain areas. Immunotitration showed that approximately 65% of dehydroascorbate reductase activity of brain cytosol which was recovered in the ammonium sulphate fraction can be attributed to this enzyme. Using immunohistochemistry, we found that a variety of brain areas expresses the enzyme. Immunoreactivity was confined to the gray matter. Amongst the several brain regions, the cerebellum appears to be the most densely stained. The enzyme was also abundant in the hippocampus and the olfactory cortex. The lesion of norepinephrine terminals following systemic administration of DSP-4 markedly decreased immunoreactivity in the cerebellum. Apart from the possible co-localization of the enzyme with norepinephrine, the relative content of dehydroascorbate reductase in different brain regions might be crucial in conditioning regional sensitivity to free radical-induced brain damage. Given the scarcity of protective mechanisms demonstrated in the brain, the discovery of a new enzyme with antioxidant properties might represent a starting-point to increase our knowledge about the antioxidant mechanisms operating in several central nervous system disorders.


Assuntos
Encéfalo/enzimologia , Oxirredutases/metabolismo , Animais , Axônios/fisiologia , Encéfalo/citologia , Fracionamento Celular , Cerebelo/citologia , Cerebelo/enzimologia , Corpo Estriado/citologia , Corpo Estriado/enzimologia , Citosol/enzimologia , Feminino , Lobo Frontal/citologia , Lobo Frontal/enzimologia , Glutationa/metabolismo , Hipocampo/citologia , Hipocampo/enzimologia , Hipotálamo/citologia , Hipotálamo/enzimologia , Imunoglobulina G/farmacologia , Imuno-Histoquímica , Norepinefrina/análise , Especificidade de Órgãos , Oxirredutases/análise , Ratos , Ratos Wistar , Serotonina/análise
13.
Ultrastruct Pathol ; 22(3): 253-61, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9793206

RESUMO

Analogs of geranylgeranyl diphosphate (GGdP) have been demonstrated to inhibit the geranylgeranylation of proteins, producing cytotoxic activity in human prostate cancer cells. A detailed study is reported on the programmed cell death in vitro of human exocrine pancreas cancer cells (MIA PaCa-2) induced by the most active compound of this series of geranylgeranylation inhibitors, the dipotassium salt of (E,E,E)[2-oxo-2-[[(3,7,11,15-tetramethyl-2, 6,10,14-hexadecatetraenyl)-oxy]amino]ethyl] phosphonic acid (BAL 9504), using transmission and scanning electron microscopy (SEM). The results show that, after 72 h of treatment with BAL 9504, 25 microM, most MIA PaCa-2 cells display the typical morphological features of apoptosis, including condensation of nuclear chromatin, dilation of endoplasmic reticulum, and fragmentation of both nucleus and cytoplasm, giving rise to small membrane-bound vesicles (apoptotic bodies); surface protrusions and blebs are well demonstrated by SEM. The electrophoresis showed the presence of various bands corresponding to fragmented DNA of 180 base pairs, or multiples of this length, thus indicating that BAL 9504 effectively induces apoptosis. The present study provides the first evidence that inhibition of protein geranylgeranylation produces apoptosis in human MIA PaCa-2 exocrine pancreas cancer cells.


Assuntos
Apoptose , Organofosfonatos/farmacologia , Neoplasias Pancreáticas/patologia , Prenilação de Proteína/efeitos dos fármacos , Fragmentação do DNA , Humanos , Microscopia Eletrônica , Microscopia Eletrônica de Varredura , Neoplasias Pancreáticas/ultraestrutura , Células Tumorais Cultivadas
14.
Bioorg Med Chem Lett ; 8(22): 3223-8, 1998 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-9873707

RESUMO

New fluorescent ligands for adenosine receptors are described; these compounds were obtained by the insertion, in the N6 position of NECA (a potent adenosine agonist), of dansylaminoalkyl moieties with alkyl spacers of increasing carbon chain length (from 3 to 12). Among them, the compound with a C6 alkyl spacer proved to be the most interesting one, showing a marked selectivity for the A1 receptor subtype; furthermore, in fluorescence microscopy assays it proved to be able to visualize and localize this receptor subtype at the level of the molecular layer of the rate cerebellar cortex.


Assuntos
Adenosina-5'-(N-etilcarboxamida)/análogos & derivados , Compostos de Dansil/síntese química , Corantes Fluorescentes/síntese química , Receptores Purinérgicos P1/análise , Animais , Corantes Fluorescentes/metabolismo , Ensaio Radioligante , Ratos , Relação Estrutura-Atividade
15.
Histochem J ; 30(10): 695-701, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9873996

RESUMO

The effect of repeated stress (1 h of daily immobilization for seven consecutive days) on the adrenal cortex of young adult male albino rats was evaluated by morphohistochemical methods and plasma assays; at the same time, testes and major salivary glands, as steroid-producing and -depending organs, respectively, were examined. Morphological and histochemical changes were found in the adrenal cortex, testis and submaxillary gland, though varying in degree and extent depending on the gland examined. Corticosterone and progesterone plasma levels increased, in agreement with the lipid depletion observed in the zona fasciculata, while testosterone and androstenedione decreased, as confirmed by the less marked enzymatic activity in the Leydig cells. The study thus proves that repeated stress, even of temporary duration, is able to influence directly or indirectly the morphofunctional state of the three examined glands, suggesting a functional linkage.


Assuntos
Córtex Suprarrenal/fisiologia , Glândulas Salivares/fisiologia , Estresse Fisiológico/metabolismo , Estresse Fisiológico/patologia , Testículo/fisiologia , Córtex Suprarrenal/anatomia & histologia , Córtex Suprarrenal/metabolismo , Androstenodiona/sangue , Animais , Peso Corporal , Corticosterona/sangue , Desidroepiandrosterona/metabolismo , Masculino , Tamanho do Órgão , Progesterona/sangue , Radioimunoensaio , Ratos , Ratos Wistar , Restrição Física , Glândulas Salivares/anatomia & histologia , Glândulas Salivares/metabolismo , Estresse Fisiológico/fisiopatologia , Glândula Submandibular/anatomia & histologia , Glândula Submandibular/metabolismo , Testículo/anatomia & histologia , Testículo/metabolismo , Testosterona/sangue
16.
Exp Toxicol Pathol ; 48(4): 299-305, 1996 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8811298

RESUMO

The effect of chronic suramin administration on rat testis was evaluated. The animals were given the drug twice a week for two months, following a treatment schedule comparable to that used in cancer therapy. Light microscopic sections revealed vacuolizations near the basal lamina, germ cells very little differentiated, together with immature cells located in the lumen of seminiferous tubules. Ultrastructural changes were revealed in the form of a decrease in nuclear density with evaginations of the nuclear envelope and sometimes ruptures of the plasmatic membrane. Changes in the Sertoli cells consisted of cytoplasm vacuolizations, in which some lysosomes, containing degraded material such as myelin-like figures, were present.


Assuntos
Suramina/toxicidade , Testículo/efeitos dos fármacos , Testículo/ultraestrutura , Animais , Masculino , Ratos , Ratos Wistar
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