Rosai-Dorfman disease: isolated epibulbar masses in two adult patients.
Explore the source record for details and available documents.
Aged↗
Biomedical subjects
M M de Souza
Publications and source records attributed to M M de Souza.
Experimental evidence for exciton scaling effects in self-assembled molecular wires.
Resonant Rayleigh scattering from self-assembled one-dimensional molecular J-aggregate wires reveals a distinct dependence of the exciton energy on the width of lateral extension. For the J aggregates used in this study, strong in-line dipole coupling leads to a delocalization of the exciton wave function over several molecular units. Polarization dependent measurements of resonantly scattered light from the wires show that the exciton dipole moment is oriented perpendicular to the long axis. The experimental observations can be described by applying a quantization condition to the center of mass motion of the J-band exciton in the wires.
Journal Article↗
Phytochemical analysis and analgesic properties of Curcuma zedoaria grown in Brazil.
The present study describes the phytochemical analysis and analgesic activity of Curcuma zedoaria rhizomes grown in Brazil. The results showed that the hydroalcoholic extract, fractions, specially dichloromethane, and a pure compound, denoted as curcumenol (1), exhibited potent and dose-related analgesic activity when evaluated in several models of pain in mice, including writhing, formalin and capsaicin. Compound (1), which seems to be the main active principle from this plant, presented promising analgesic effects, being several times more potent than different reference drugs evaluated in the same experimental models. The calculated ID50 values (micromol/kg, i.p) were 22 and 12 when evaluated in writhing and capsaicin tests, respectively, and 29 micromol/kg in relation to the second phase of the formalin model. The lack of effect in the hot plate test suggests that (1) act by a mechanism which do not involves the participation of the opioid system. The phytochemical analysis indicated that the chemical composition of the plant grown in Brazil is similar to that grown in other countries. The results confirm and justify the popular use of this plant for the treatment of dolorous processes.
Analgesics↗
4-Nitro-1,8-naphthalimides exhibit antinociceptive properties.
Explore the source record for details and available documents.
Acetic Acid↗
Comparative histopathology of endomyocardial biopsies in chagasic and non-chagasic heart transplant recipients.
BACKGROUND: Heart transplantation has been an option for the treatment of chagasic (C) cardiomyopathy despite difficulties concerning the control of rejection and reactivation. The parasite-host interaction under the influence of immunosuppressive therapy may affect the immunological response to the graft in a pattern different from that in non-chagasic (NC) patients. The aim of this study was to compare the major histopathological features in heart transplantation in C and NC patients. METHODS: We studied 293 endomyocardial biopsies from two groups of heart transplanted patients, including 18 C and 15 NC. Both groups had identical surgical and clinical procedure except immunosuppressive therapy was lower in C patients. The histopathological parameters evaluated were the Quilty effect, rejection, C myocarditis reactivation, fibrosis, hypertrophy, and ischemia. In addition, lymphocytic cellular infiltration of myocarditis due to rejection or reactivation was immunophenotyped in the biopsies of both groups with rejection grades 3 to 4, in biopsies with signs of reactivation, and in fragments of the receptor heart with chronic C myocarditis. A search for Trypanosoma cruzi was performed in all biopsies in the C group in which lymphocyte immunophenotyping was done. We used immunofluorescence and confocal microscopy. RESULTS: The Quilty effect was present in 23% of the biopsies, involving 69.7% of the patients without a significant difference between groups (p = 0.509). Rejection was frequently observed in biopsies with the Quilty effect and the effect often recurred in the same patient. Rejection grades 3 to 4 was more frequent in the C group (p = 0.023). There were 5 episodes of Chagas' disease reactivation with myocarditis in 2 cases. The mean numbers of CD8+ and CD4+ T cells, and the CD4+-to-CD8+ ratio were similar for rejection in both groups (p > 0.05), while the CD4+-to-CD8+ ratio was significantly lower in chronic C myocarditis compared to rejection in the C group (p = 0.043). There was no significant difference in ischemic damage or interstitial fibrosis in the groups but there was a higher frequency of hypertrophy in the NC group (p = 0.007). CONCLUSIONS: The histopathological features of heart transplantation in C patients did not differ from that in NC patients in regard to the Quilty effect, development of myocardial fibrosis and ischemia. However, the higher involvement of the C group for rejection grades 3 to 4 suggested higher susceptibility to this event. The similarity of the lymphocytic cellular composition for rejection in both groups indicates that C patients respond to immunological stimulus in a similar pattern as NC patients.
Adolescent↗
Effects of infusions of the tyrosine kinase inhibitor radicicol into the hippocampus on short- and long-term memory of the inhibitory avoidance task.
The aim of the present work was to test the role of protein tyrosine kinases (PTKs) on both the short-term memory (STM) and long-term memory (LTM) of the inhibitory avoidance task in rats using the inhibitor of tyrosine kinase, radicicol. Rats implanted with cannulae in the CA1 area of the dorsal hippocampus received a 0.5 microl infusion of radicicol (0.5, 1, 5, 10, 20 microg/ml) or vehicle (water) at different times after training and were tested for STM (1.5 or 3 h) and LTM (24 h). Additionally, one group received radicicol 10 min prior to the test for LTM. Radicicol depressed both STM and LTM when infused before and immediately after training and had no effect on either form of memory when infused 30 or 90 min after training. Radicicol also depressed the retrieval of LTM. Our results indicate that memory formation and retrieval in the hippocampus can involve PTK activity, but the present findings should be taken merely as a possible starting point for future investigations.
Animals↗
LY294002, an inhibitor of phosphoinositide 3-kinase given into rat hippocampus impairs acquisition, consolidation and retrieval of memory for one-trial step-down inhibitory avoidance.
Adult male Wistar rats were bilaterally implanted with indwelling cannulae in the CA1 region of the dorsal hippocampus. Once recovered from surgery, animals were submitted to one session of step-down inhibitory avoidance training (3.0 s, 0.4 mA footshock). Animals received a 0.5-microl infusion of saline, or of LY294002 (5, 50 or 500 microM), an inhibitor of the phosphoinositide 3-kinase (PI 3-K) family. Infusions were given 10 min before training, immediately post-training or 10 min prior to a 24-h retention test. In the pre- and post-training groups, the animals were tested twice: at 1.5 and 24 h after training, for short- (STM) and long-term memory (LTM), respectively. Pre- and post-training infusion of the drug inhibited both STM and LTM. Pre-test infusions impaired LTM retrieval. The effects can not be attributed to influences on locomotor, exploratory, pro- or anti-conflict behaviour, since LY294002 had no influence on elevated plus-maze behaviour. The results suggest that hippocampal PI 3-K is necessary for memory acquisition, consolidation and retrieval of the consolidation of step-down inhibitory avoidance in rats. This could be due to an interaction with the N-methyl-d-aspartate (NMDA) receptor complex or with activity of the extracellularly regulated protein kinase (ERK)-Ras signalling pathway.
Animals↗
Pharmacological differences between memory consolidation of habituation to an open field and inhibitory avoidance learning.
Rats implanted bilaterally with cannulae in the CA1 region of the dorsal hippocampus or the entorhinal cortex were submitted to either a one-trial inhibitory avoidance task, or to 5 min of habituation to an open field. Immediately after training, they received intrahippocampal or intraentorhinal 0.5-microl infusions of saline, of a vehicle (2% dimethylsulfoxide in saline), of the glutamatergic N-methyl-D-aspartate (NMDA) receptor antagonist 2-amino-5-phosphono pentanoic acid (AP5), of the protein kinase A inhibitor Rp-cAMPs (0.5 microg/side), of the calcium-calmodulin protein kinase II inhibitor KN-62, of the dopaminergic D1 antagonist SCH23390, or of the mitogen-activated protein kinase kinase inhibitor PD098059. Animals were tested in each task 24 h after training. Intrahippocampal KN-62 was amnestic for habituation; none of the other treatments had any effect on the retention of this task. In contrast, all of them strongly affected memory of the avoidance task. Intrahippocampal Rp-cAMPs, KN-62 and AP5, and intraentorhinal Rp-cAMPs, KN-62, PD098059 and SCH23390 caused retrograde amnesia. In view of the known actions of the treatments used, the present findings point to important biochemical differences in memory consolidation processes of the two tasks.
1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine↗
Phosphorylated cAMP response element-binding protein as a molecular marker of memory processing in rat hippocampus: effect of novelty.
From mollusks to mammals the activation of cAMP response element-binding protein (CREB) appears to be an important step in the formation of long-term memory (LTM). Here we show that a 5 min exposure to a novel environment (open field) 1 hr after acquisition of a one-trial inhibitory avoidance training hinders both the formation of LTM for the avoidance task and the increase in the phosphorylation state of hippocampal Ser 133 CREB [phosphorylated CREB (pCREB)] associated with the avoidance training. To determine whether this LTM deficit is attributable to the reduced pCREB level, rats were bilaterally cannulated to deliver Sp-adenosine 3', 5'-cyclic monophosphothioate (Sp-cAMPS), an activator of PKA. Infusion of Sp-Adenosine 3',5'-cyclic monophosphothioate Sp-cAMPS to CA1 region increased hippocampal pCREB levels and restored normal LTM of avoidance learning in rats exposed to novelty. Moreover, a 5 min exposure to the open field 10 min before the avoidance training interferes with the amnesic effect of a second 5 min exposure to the open field 1 hr after avoidance training and restores the hippocampal levels of pCREB. In contrast, the avoidance training-associated activation of extracellular signal-regulated kinases (p42 and p44 mitogen-activated protein kinases) in the hippocampus is not altered by novelty. Together, these findings suggest that novelty regulates LTM formation by modulating the phosphorylation state of CREB in the hippocampus.
Amnesia, Retrograde↗
Antinociceptive properties of the methanolic extract obtained from Ipomoea pes-caprae (L.) R. Br.
Ipomoea pes-caprae is a medicinal plant used in many countries for the treatment of several ailments, including inflammatory and algesic processes. The present study describes the antinociceptive effects of the methanolic extract and two fractions obtained from aerial parts of this plant. The results indicated that both methanolic extract and two fractions (ethyl acetate and aqueous) exhibited considerable antinociceptive activity against two classical models of pain in mice. Methanolic extract presented a calculated ID50 value of 33.8 mg/kg, i.p. against writhing test and also inhibited both phases of pain (neurogenic and inflammatory) of the formalin test with ID50 of 37.7 and 12.5 mg/kg, i.p. for the first and second phase, respectively. Preliminary phytochemical analysis suggested the presence of steroids, terpenoids, alkaloids and flavonoids. These findings support, at least in part, the popular use of I. pes-caprae to treat dolorous processes.
Analgesics↗
Antinociceptive activity of I3,II8-binaringenin, a biflavonoid present in plants of the guttiferae.
This paper describes the antinociceptive action of 13,118-binaringenin (GB-1a), a biflavonoid isolated from Clusia columnaris and present in several plants of the family Guttiferae, in a writhing test and a formalin test. It was found that it exhibits potent and dose-related antinociceptive action in both experimental models, with ID50 values of 22 mumol/kg against the writhing test and 28 mumol/kg against the second phase of the formalin test. It was more potent than some well-known analgesic drugs used as reference. Based on a hot-plate test its mechanism of action seems to be unrelated with the opioid receptors.
Analgesics, Non-Narcotic↗
Hepatic capillariasis in rats: a new model for testing antifibrotic drugs.
Rats infected with the helminth Capillaria hepatica regularly develop septal hepatic fibrosis that may progress to cirrhosis in a relatively short time. Because of such characteristics, this experimental model was selected for testing drugs exhibiting antifibrosis potential, such as pentoxifylline, gadolinium chloride and vitamin A. Hepatic fibrosis was qualitatively and quantitatively evaluated in liver samples obtained by partial hepatectomy and at autopsy. The material was submitted to histological, biochemical and morphometric methods. A statistically significant reduction of fibrosis was obtained with pentoxifylline when administered intraperitoneally rather than intravenously. Gadolinium chloride showed moderate activity when administered prophylactically (before fibrosis had started), but showed a poor effect when fibrosis was well advanced. No modification of fibrosis was seen after vitamin A administration. Hydroxyproline content was correlated with morphometric measurements. The model appears to be adequate, since few animals die of the infection, fibrosis develops regularly in all animals, and the effects of different antifibrotic drugs and administration protocols can be easily detected.
Animals↗
Melanin-concentrating hormone (MCH) modifies memory retention in rats.
The purpose of the present study was to evaluate the possible effect of melanin-concentrating hormone (MCH) on learning and memory by using the one-trial step-down inhibitory avoidance test in rats. The peptide was infused into hippocampus, amygdala, and entorhinal cortex. MCH caused retrograde facilitation when given at 0 or 4 h post-training into hippocampus, but only at 0 h into amygdala. From these results, it seems that MCH modulates memory early after training by acting on both the amygdala and hippocampus and, 4 h after training, on the hippocampus.
Amygdala↗
Effects of post-training infusions of a mitogen-activated protein kinase kinase inhibitor into the hippocampus or entorhinal cortex on short- and long-term retention of inhibitory avoidance.
We recently demonstrated the time-dependent impairment of long-term retention of a step-down inhibitory avoidance task in rats induced by post-training infusion of the specific MAPKK (mitogen-activated protein kinase kinase) inhibitor PD 098059 into the hippocampus (HIP), amygdala (AMY), entorhinal cortex (EC) and posterior parietal cortex (PPC). Here we investigate the role of the MAPK cascade in the HIP and the EC on both short- and long-term retention of inhibitory avoidance in rats, using three different doses of the MAPKK inhibitor PD 098059. Adult male Wistar rats were trained and tested in inhibitory avoidance and given an infusion of PD 098059 (0.5, 5.0 or 50.0 microM) at 0, 30, 90, 120, 180, 270 or 360 min after training. A retention test session was carried out at 90, 180 or 270 min after training (short-term memory, STM) and/ or 24 h after training (long-term memory, LTM). When infused into the HIP at 0 min, but not at 30, 90, 120 or 180 min after training, PD 098059 impaired STM. Intrahippocampal PD 098059 impaired LTM when infused at 180 min, but not at 0, 30, 90, 120 or 270 min after training. When infused into the EC, PD 098059 enhanced STM when given at 0 min after training and had no effect when given at 30, 90, 120 or 180 min after training. In this structure, PD 098059 impaired LTM when given at 180 or 270 min, but not at 30, 90, 120 or 360 min after training. All effects were dose-dependent. These findings indicate that the MAPK cascade in the HIP and EC is differentially involved in short- and long-term retention of inhibitory avoidance in rats.
Animals↗
[I Guidelines of the Brazilian Cardiology Society for Heart Transplantation: IV. Rejection].
Explore the source record for details and available documents.
Acute Disease↗
Mechanisms for memory types differ.
Explore the source record for details and available documents.
Animals↗
Short- and long-term memory are differentially regulated by monoaminergic systems in the rat brain.
Rats with cannulae implanted in the dorsal CA1 region of the hippocampus or in the entorhinal cortex (EC) were trained in one-trial step-down inhibitory avoidance and tested 1.5 or 24 h later, in order to measure short-term memory (STM) and long-term memory (LTM) respectively. Several drugs infused immediately post-training inhibited STM without altering LTM: the D1 receptor agonist SKF38393 (7.5 microgram) given into either CA1 or EC, the beta blocker timolol (0.3 microgram) given into EC, the 5HT1A receptor agonist 8-HO-DPAT (2.5 microgram) given into CA1, and the 5HT1A antagonist NAN-190 (2.5 microgram) given into EC. These findings indicate that STM is not a necessary step toward LTM. Intraentorhinal 8-HO-DPAT enhanced STM and depressed LTM. The D1 antagonist SCH23390 (0.5 microgram) enhanced STM without affecting LTM when given into CA1, and blocked LTM without affecting STM when given into EC. Intraentorhinal norepinephrine (0.3 microgram) enhanced both STM and LTM, and the same drug when given into CA1 enhanced LTM selectively. None of the drugs had any effect on retrieval of either STM or LTM when given prior to testing. The data indicate that STM and LTM are differentially modulated by D1, beta, and 5HT1A receptors in CA1 and EC.
2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-ben↗
Chemical and pharmacological examination of antinociceptive constituents of Wedelia paludosa.
The present work describes the antinociceptive effects of some fractions and two pure compounds obtained from the Wedelia paludosa, a Brazilian medicinal plant employed in folk medicine against a variety of diseases, including dolorous pathologies. It was found that such fractions as well as kaurenoic acid and luteolin exhibit marked antinociceptive action in mice using acetic acid-induced writhing. They were more active than some well-known analgesic drugs, such as acetyl salicylic acid, acetaminophen, dipyrone and indomethacin. The results confirm our previous studies conducted with this plant, suggesting that different chemical constituents are responsible for the antinociceptive activity shown by the extracts and fractions prepared from W. paludosa.
Abdomen↗