Edema cerebral crônico na neurocisticercose

Neste estudo retrospectivo, relatam-se as características clínicas do edema cerebral crônico (ECCr) em 34 pacientes com neurocisticercose (NCC), que apresentavam edema cerebral difuso, à tomografia computadorizada (TC), como característica comum. Todos foram tratados com dextroclorofeniramina e, 32 deles, com albendazol. O ECCr predominou no sexo feminino (73,5%) na faixa etária dos 11 - 40 anos (92,3%). A cefaléia ocorreu em 94,1% dos pacientes, náuseas/vômitos em 47,1%, crises epilépticas em 41,1% e distúrbios psíquicos em 38,2%. A hiperreflexia ocorreu em 82,3% e o papiledema em 58,8% e o exame neurológico normal em 11,8%. Na TC, o edema esteve associado a calcificações em 61,8% dos casos. As pressões liquóricas foram mais elevadas (p< 0,05) antes do tratamento. Atualmente, estão assintomáticos, ou com melhora clínica, 79,4% dos pacientes (57,1% deles sem medicação). Discute-se a possibilidade do ECCr, na NCC, ser uma manifestação antigênica, sem a presença concomitante de cistos parasitários, e poder representar mais uma condição clínica associada à hipertensão intracraniana benigna.

Neurocysticercosis: The enigmatic disease

Neurocysticercosis (NCC) is an infection of the central nervous system (CNS) caused by the metacestode larval form of the parasite Taenia sp. Many factors can contribute to the endemic nature of cysticercosis. The inflammatory process that occurs in the tissue surrounding the parasite and/or distal from it can result from several associated mechanisms and may be disproportionate with the number of cysts. This discrepancy may lead to difficulty with the proper diagnosis in people from low endemic regions or regions that lack laboratory resources. In the CNS, the cysticerci have two basic forms, isolated cysts (Cysticercus cellulosae = CC) and racemose cysts (Cysticercus racemosus = CR), and may be meningeal, parenchymal, or ventricular or have a mixed location. The clinical manifestations are based on two fundamental syndromes that may occur in isolation or be associated: epilepsy and intracranial hypertension. They may be asymptomatic, symptomatic or fatal; have an acute, sub-acute or chronic picture; or may be in remission or exacerbated. The cerebrospinal fluid (CSF) may be normal, even in patients with viable cysticerci, until the patients begin to exhibit the classical syndrome of NCC in the CSF, or show changes in one or more routine analysed parameters. Computed tomography (CT) and magnetic resonance imaging (MRI) have allowed non-invasive diagnoses, but can lead to false negatives. Treatment is a highly controversial issue and is characterised by individualised therapy sessions. Two drugs are commonly used, praziquantel (PZQ) and albendazole (ABZ). The choice of anti-inflammatory drugs includes steroids and dextrochlorpheniramine (DCP). Hydrocephalus is a common secondary effect of NCC. Surgical cases of hydrocephalus must be submitted to ventricle-peritoneal shunt (VPS) immediately before cysticidal treatment, and surgical extirpation of the cyst may lead to an absence of the surrounding inflammatory process. The progression of NCC may be simple or complicated, have remission with or without treatment and may exhibit symptoms that can disappear for long periods of time or persist until death. Unknown, neglected and controversial aspects of NCC, such as the impaired fourth ventricle syndrome, the presence of chronic brain oedema and psychic complaints, in addition to the lack of detectable glucose in the CSF and re-infection are discussed. © 2011 Bentham Science Publishers.

Intravitreal triamcinolone versus bevacizumab for treatment of refractory diabetic macular oedema (IBEME study)

Background/aims: The aim of this study was to compare the morphological and visual acuity outcomes associated with a single intravitreal injection of triamcinolone acetonide versus bevacizumab for the treatment of refractory diffuse diabetic macular oedema.Methods: Twenty-eight patients were randomly assigned to receive a single intravitreal injection of either 4 mg/0.1 ml triamcinolone acetonide or 1.5 mg/0.06 ml bevacizumab. Comprehensive ophthalmic evaluation was performed at baseline and at weeks 1, 4, 8 (+/- 1), 12 (+/- 2) and 24 (+/- 2) after treatment. Main outcome measures included central macular thickness measured with optical coherence tomography (OCT) and best corrected Early Treatment Diabetic Retinopathy Study (ETDRS) visual acuity.Results: Twenty-six patients (26 eyes) completed all study visits (two patients missed two consecutive study visits). Central macular thickness was significantly reduced in the intravitreal triamcinolone group compared with the bevacizumab group at weeks 4, 8, 12 and 24 (p<0.05). Logarithm of the minimum angle of resolution (LogMAR) best-corrected visual acuity was significantly higher at weeks 8 (0.69; similar to 20/100(+1)) and 12 (0.74; 20/100(-2)) in the intravitreal triamcinolone group compared with the bevacizumab group (weeks 8 (0.83; similar to 20/125(-1)) and 12 (0.86; 20/ 160(+2))) (p<0.05). Significant change from baseline in mean intraocular pressure (mmHg) was seen at week 4 (+2.25) only in the intravitreal triamcinolone group (p<0.0001). No patient had observed cataract progression during the study.Conclusions: One single intravitreal injection of triamcinolone may offer certain advantages over bevacizumab in the short-term management of refractory diabetic macular oedema, specifically with regard to changes in central macular thickness. The actual clinical relevance of our preliminary findings, however, remains to be determined in future larger studies.

Astrocytic and microglial response and histopathological changes in the brain of horses with experimental chronic Trypanosoma evansi infection

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Effect of heat stress or lipopolysaccharide (E-coli) injection on HSP70 levels in the liver and brain of adrenalectomized rats

Hsp70 content (ng Hsp70 mu g total protein(-1)) in the liver and brain of control and adrenalectomized male rats was investigated by Western Blotting after heat stress (40 degrees C) or endotoxin-induced fever (E. coli lipopolysaccharide injection). The increase in rectal temperature was higher after heat stress than after LPS injection, Heat stress affected Hsp70 content of the liver, but not of the brain; however adrenalectomy did not influence any parameter. These results suggest that, under these circumstances, there is no relationship between the hypothalamic-pituitary-adrenal axis and Hsp70 synthesis in liver and brain. (C) 2000 Elsevier B.V. Ltd. All rights reserved.

Role of brain nitric oxide in the thermoregulation of broiler chicks

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Brain monoaminergic neurons and ventilatory control in vertebrates

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Toxoplasma gondii: Evaluation of an intranasal vaccine using recombinant proteins against brain cyst formation in BALB/c mice

The purpose of this work was to evaluate protective activity against brain cyst formation in BALB/c mice intranasally vaccinated with recombinant proteins from Toxoplasma gondii. The recombinant proteins rROP2, rGRA5 and rGRA7 were used in vaccine preparation. Thirty-three female mice were divided into three groups, these animals received two doses by intranasal route at days 0 and 21 as follows; group 1 (G1, n = 11) received 12.5 mu g of each recombinant protein plus 0.5 mu g of cholera toxin, group 2 (G2, n = 11) received phosphate buffer saline (PBS) plus 0.5 mu g of cholera toxin, and group 3 (G3, n = 11) received PBS only. At challenge day (day 33) three animals from each group were euthanatized for IgA measure from intestine. Mice were infected orally with 50 cysts from the VEG strain at day 33. At challenge day the G1 animals had high immunoglobulin A levels, however, they only showed IgG antibody titers against rROP2 and rGRAT Animals from G1 also exhibited strong resistance to cyst formation compared with the control group (G3, P < 0.05). However, we did not observe differences in protection against brain cyst formation between G1 and G2 (P > 0.1). These results indicate that intranasal immunization in BALB/c mice with recombinant proteins rROP2, rGRA5 and rGRA7 associated with cholera toxin induced partial protection, when compared with G3, against tissue cyst formation after oral infection with tissue cysts from T gondii. (c) 2007 Elsevier B.V. All rights reserved.

Detection of bovine herpesvirus 5 (BoHV-5) in formalin-fixed, paraffin-embedded bovine brain by nested PCR in Colombian cattle

Fifteen cases of viral meningoencephalitis in Colombian cattle were tested by nested PCR analysis for the detection of bovine herpesvirus 5 (BoHV-5). All fatal cases had shown severe neurological signs and had occurred following natural outbreaks of the disease. The neurological infection was histologically characterized by mild to moderate inflammatory changes in the brain and cerebellum, including meningitis, mononuclear perivascular cuffing, gliosis, haemorrhage, and the presence of Gitter cells (macrophages) accompanying large areas of malacia. No intranuclear inclusion bodies were seen in any of the cases. Results from BoHV-5 molecular extraction analyses showed there were five positive cases thus confirming the presence of the virus in Colombia.

Immunohistochemical characterization of mononuclear cells and MHC II expression in the brain of horses with experimental chronic Trypanosoma evansi infection

Este estudo objetivou caracterizar a resposta imune celular no sistema nervoso central (SNC) de eqüinos com infecção crônica experimental por Trypanosoma evansi. Para este propósito, foram utilizados os métodos histoquímicos (HE) e imunoistoquímicos do complexo avidina-biotina peroxidase (ABC). O fenótipo do infiltrado celular foi caracterizado com o auxílio de anticorpos anti - CD3, para linfócitos T e antiBLA36 para linfócitos B. Os macrófagos foram marcados com anticorpo antiantígenos da linhagem mielóide/histiócitos (Clone Mac387). A lesão no sistema nervoso central (SNC) dos eqüinos infectados com T. evansi foi caracterizada como meningoencefalite e meningomielite não supurativa. A gravidade das lesões variou em diferentes segmentos do SNC, refletindo distribuição irregular das alterações vasculares. A distribuição de células T e B e antígenos do complexo maior de histocompatibilidade classe II foram avaliados dentro do SNC de eqüinos cronicamente infectados com T. evansi. O infiltrado perivascular e meníngeo eram constituídos predominantemente por células T e B. Macrófagos foram raramente visualizados. T.evansi não foi identificado no parênquima do SNC dos eqüinos.

Brain and hepatic Hsp70 protein levels in heat-acclimated broiler chickens during heat stress

In the present study we have investigated the effects of heat acclimation on brain and hepatic Hsp70 protein levels and body temperature of broiler chickens in response to gradual heat stress. Two groups of broilers were raised up to 47 days of age under distinct temperature conditions: thermoneutral (TN, according to bird age) or hot environmental (HS, 31-33°C). At 46 days of age, the birds reared at high ambient temperature were transferred to thermoneutrality conditions. After 18 h, these birds and the birds reared at thermoneutral temperature were submitted to gradual heat stress in a climatic chamber so that environment temperature was increased from 28 to 40ºC at a rate of 2ºC/h. Colonic temperature was measured using a thermometer sensor probe at each two hours, and hepatic and brain tissues were collected immediately after slaughter in order to assess Hsp70 protein level by Western blotting analysis. The colonic temperatures of birds reared at high temperature increased steeply during the first 2 h of heat stress (1.06ºC/h) and more slowly thereafter (0.59ºC/h). Broilers reared at thermoneutral temperature showed a small increase in the first 4 h of heat stress (0.18ºC/h) and then colonic temperature increased sharply (0.72ºC/h). Nevertheless, both groups presented similar final colonic temperature by the end of the stress period. Hsp70 levels (ng Hsp70 µg total protein-1) did not change in the liver or brain of the birds reared at high temperature. on the other hand, both liver and brain Hsp70 levels increased significantly during heat stress in the animals reared at thermoneutrality, with a higher expression of this peptide in brain tissue.

Hypoxic-preconditioning induces neuroprotection against hypoxia-ischemia in newborn piglet brain

Preconditioning-induced ischemic tolerance has been documented in the newborn brain, however, the signaling mechanisms of this preconditioning require further elucidation. The aims of this study were to develop a hypoxic-preconditioning (PC) model of ischemic tolerance in the newborn piglet, which emulates important clinical similarities to human situation of birth asphyxia, and to characterize some of the molecular mechanisms shown to be implicated in PC-induced neuroprotection in rodent models. One day old piglets were subjected to PC (8% O(2)/92% N(2)) for 3 h and 24 h later were exposed to hypoxia-ischemia (HI) produced by a combination of hypoxia (5% FiO(2)) for a period of 30 min and ischemia induced by a period of hypotension (10 min of reduced mean arterial blood pressure; 70% of baseline). Neuropathologic analysis and unbiased stereology, conducted at 24 h, 3 and 7 days of recovery following HI, indicated a substantial reduction in the severity of brain damage in PC piglets compared to non-PC piglets (P<0.05). PC significantly increased the mRNA expression of hypoxia-inducible factor-1 alpha (HIF-1 alpha) and its target gene, vascular endothelial growth factor (VEGF) at 0 h, 6 h, 24 h, 3 and 7 days of recovery. Immunoblot analysis demonstrated that PC resulted in HIF-1 alpha protein stabilization and accumulation in nuclear extracts of cerebral cortex of newborn piglet brain compared to normoxic controls. Protein levels of VEGF increased in a time-dependent manner in both cortex and hippocampus following PC. Double-immunolabeling indicated that VEGF is mainly expressed in neurons, endothelial cells and astroglia. Our study demonstrates for the first time the protective efficacy of PC against hypoxic-ischemic injury in newborn piglet model, which recapitulates many pathophysiological features of asphyxiated human neonates. Furthermore, as has been shown in rodent models of preconditioning, our results suggest that PC-induced protection in neonatal piglets may involve upregulation of VEGF. (C) 2011 Elsevier B.V. All rights reserved.

Effect of the bacillus of Calmette-Guerin, Propionibacterium acnes and avridine as immunomodulators in antirabies vaccination of mice using the Fuenzalida-Palacios mouse brain vaccine

Using the laboratory mice, Fuenzalida-Palacios mouse brain human rabies vaccine was administered in groups of animals previously inoculated with rabies virus and then submitted to treatments with the immunomodulators onco-BCG, avridine and Plopionibacterium acnes. Humoral and cellular immune responses were evaluated through the macrophage inhibition factor (MIF), intra-pad inoculation (IPI) and serum neutralization (SN) tests and by the detection of gamma-interferon (IFN-gamma). The IPI test was not effective in detecting the response of delayed-type hypersensitivity, contrary to MIF, which showed the immune cellular response. Higher levels of IFN-gamma were observed in the groups of mice vaccinated and treated with avridine and P. acnes. Although immunomodulating activities have been detected, the use of adjuvants with the Fuenzalida-Palacios type vaccine in mice did not reveal any encouraging results. (C) 1999 Elsevier B.V. Ltd. All rights reserved.

Detection of bovine Herpesvirus type 5 in formalin-fixed, paraffin-embedded bovine brain by PCR: a useful adjunct to conventional tissue-based diagnostic test of bovine encephalitis

The aim of this study was to evaluate the application of PCR technique for the detection of BoHV-5 in routinely formalin-fixed, paraffin-embedded brain tissues in 20 naturally infected calves affected by fatal meningoencephalitis. Brains were divided into two halves, one kept fresh for virus isolation and PCR assay, targeting the glycoprotein C gene from BoHV-5 genome. The other half brain, corresponding to posterior cortex region, was submitted to formalin fixation and embedded into paraffin blocks for microscopic evaluation and total DNA isolation. Most of the slides showed severe multifocal non-supurative encephalitis with neuronal degeneration, neurophagia, and no acidophilic intranuclear inclusions could be found in neurons and glial. The 20 fresh samples were confirmed, by virus isolation and PCR assay, as having the BoHV-5 virus and, respective glicoprotein C sequence, while 15 of 20 formalin-fixed, paraffin-embedded samples were considered positive for the same analysis. The results revealed the first description of PCR efficiency, applied to formalin-fixed, paraffin-embedded brain collected from naturally infected calves, improving the detection of BoHV-5 from archival samples in South America. (c) 2007 Published by Elsevier B.V.