ObjectivesThe kinetics of three serological markers (IgM, IgA, and IgG) in serum, saliva, and urine samples from adult patients with primary or secondary dengue infection were studied.DesignSerum, saliva, and urine samples were collected from 22 patients with clinical and confirmed dengue 3 virus infection during the outbreak in Havana City in 2001. They were tested by capture IgM (MAC-ELISA), IgA (AAC-ELISA), and IgE (EAC-ELISA) and IgG ELISA inhibition method (EIM) to detect specific dengue antibodies.ResultsSimilar kinetics were observed in IgM, IgA, and IgG antibodies in saliva and IgA and IgG in urine samples from secondary cases compared with kinetics in serum samples, although the values were lower. No IgG antibody was detected in saliva and urine samples in primary cases and IgM antibody was not detected in urine samples from either primary or secondary infection. All secondary cases were positive for IgG in saliva and urine samples at day 7. The kinetics of specific IgE antibodies in primary and secondary cases were different.ConclusionsThe kinetics of three serological markers (IgM, IgA, and IgG) in serum, saliva, and urine samples from adult patients with primary or secondary dengue 3 virus infection were studied for the first time, showing its behavior and usefulness in dengue virus diagnosis. The specific IgE could play a role as a serological marker in secondary infections.

Background: The detection of the IgM antibody for the dengue virus in serum by ELISA has become one of the most important and useful methods for diagnosis of dengue using a single acute-phase serum sample. Currently, this system is an invaluable tool for the surveillance of dengue fever (DF) and dengue hemorrhagic fever (DHF). The usefulness of other serological markers such as IgA and IgE have been less studied.Objective: To study the IgM, IgA and IgE specific antibody response in dengue 3 infected patients with different clinical picture and type of infection.Study design: One hundred and twenty-seven serum samples collected on days 5-7 at the onset of fever from clinically and serologically confirmed dengue cases were studied. Forty-two were classified as primary dengue fever cases, 48 as secondary dengue fever cases and 37 as secondary dengue hemorrhagic fever cases. All samples were tested by capture ELISA in order to detect dengue IgM, IgA and IgE antibodies.Results and conclusions: In this study, significant differences were observed in the IgM, IgA and IgE response between the study groups. High IgA and IgE OD ratios in secondary dengue cases were found. The usefulness of serotype specific IgM antibody detection is also analyzed and discussed. A priority for future dengue research in terms of protection, recovery of infection and immunopathogenesis is to elucidate the role of these immunoglobulins. The cross reactivity response to IgM between dengue virus serotypes in primary and secondary cases should also be more studied. (C) 2004 Elsevier B.V. All rights reserved.

To examine the amounts and role of growth factors in different tissues and corporal fluid, new sensitive techniques have to be developed. A major problem is that the normal concentration of trophic substances, such as nerve growth factor (NGF), in central and peripheral nervous system and in fluids is very low (ng pg/ml). A valuable method of research is the sensitive two site enzyme immunoassay using the monoclonal antibody 27/21 to mouse NGF. Materials and methods. The present work applied this enzyme immunoassay to examine the NGF levels in normal non human primate sera (n= 94) and applied this assay to study of NGF levels in two non human primate receiving NGF infusion: one young and one aged. Two groups of non human primate sera were studied one young adult (n= 69) and one aged (n= 25). The serum samples NGF treated non human primate were taken before the infusion and at the 1st week and 1st, 3rd, 6th and 12th month after infusion.To further test the specificity of conjugate binding, dilutions of the non human primate sera were preincubated with an excess of monoclonal NGF antibody 27/21 in solution. With this strategy it was possible to completely block the signal obtained using the enzyme immunoassay. We found very low levels of NGF in aged monkeys (0.054 ng/ml) when compared with young adult group (0.152 ng/ml) (p> 0.01). The NGF levels in aged non human primate treatment with NGF was very low before (0.50 ng/ml) and during NGF treatment evolution time, whereas at the the 12th month showed an increase in NGF levels (0.180 ng/ml). We found normal values of NGF in the young monkey before and during the first year after NGF infusion.Using the enzyme immunoassay described it is possible to know the serum concentration of NGF immunoreactive in non human primate and this assay is able to detect peripheral changes in NGF levels after intracerebral infusion of NGF.

Introduction. To examine the amounts and role of growth factors in different tissues and corporal fluid, new sensitive techniques have to be developed A major problem is that the normal concentration of trophic substances, such as nerve growth factor (NGF), in central and peripheral nervous system and in fluids is very low (ng(..)pg/ml). A valuable method of research is the sensitive two-site enzyme immunoassay using the monoclonal antibody 27/21 to mouse NGF. Materials and methods. The present work applied this enzyme immunoassay to examine the NGF levels in normal non-human primate sera (n = 94) and applied this assay to study of NGF levels in two non-human primate receiving NGF infusion: one young and one aged. Two groups of non-human primate sera were studied one young-adult (n = 69) and one aged (n = 25). The serum samples NGF treated non-human primate were taken before the infusion and at the 1st week and 1st, 3rd, 6th and 12th month after infusion. Results. To further test the specificity of conjugate binding, dilutions of the non-human primate sera were preincubated with an excess of monoclonal NGF antibody 27/21 in solution. With this strategy it was possible to completely block the signal obtained using the enzyme immunoassay. We found very low levels of NGF in aged monkeys (0.054 ng/ml) when compared with young-adult group (0.152 ng/ml) (p > 0.01). The NGF levels in aged non-human primate treatment with NGF was very low before (0.50 ng/ml) and during NGF treatment evolution time, whereas at the the 12th month showed an increase in NGF levels (0.180 ng/ml). We found normal values of NGF in the young monkey before and during the first year after NGF infusion. Conclusions. Using the enzyme immunoassay described it is possible to know the serum concentration of NGF immunoreactive in non-human primate and this assay is able to detect peripheral changes in NGF levels after intracerebral infusion of NGF.

INTRODUCTION:The effects of Nerve Growth Factor (NGF) within and outside the nervous system have been amply discussed in recent decades. Recently clinical studies have shown the effectiveness of this growth factor in the treatment of neurodegenerative disorders. This clinical use makes it necessary to have sensitive, specific methods available to permit measurement of the level of this protein and to determine how it behaves during the course of treatment.OBJECTIVE:To describe the measurement of NGF levels in human serum using an immunoenzymatic method and evaluating the levels of this protein in some neurological disorders. Materials and methods. NGF levels were measured in the serum of healthy persons and in patients with Alzheimer's disease (AD) Parkinson's disease (PD), amyotrophic lateral sclerosis (ALS), multiple sclerosis (MS) and Huntington's chorea (HC) using a double site immune-enzymatic assay. Murine 27/21 anti-beta-NGF monoclonal antibody was used as the antibody to cover the plate and as conjugate.RESULTS:Adding a block pass to the method, in which the sample was incubated with an excess of 27/21 antibody effectively reduced the signal observed in the immuno-enzymatic assay. A moderate reduction in beta-NGF levels was seen in the serum of patients with ALS and MS. There was a statistically significant reduction in the patients who were carriers of PD and HC.CONCLUSIONS:The significant reduction in NGF levels in patients with PD and HC may be associated with a disorder in the use of this protein in central and peripheral tissues.

INTRODUCTION AND OBJECTIVE:The memory impairment which accompanies the aging process is a manifestation of diminished cognitive function. This is intimately related to neuropathological and biochemical changes in cholinergic areas of central nervous system (CNS). Cytokines, first described as immunoregulators, are also implied in defense reactions of the brain. Some studies on the action of IL-2 on the CNS suggest an action blocking the release of acetylcholine in the hippocampus.MATERIAL AND METHODS:We have studied the possible central neurotoxic effect of this soluble factor using the chronic intraperitoneal infusion of human recombinant IL-2 (hr-IL 2) to young and old Sprague Dawley rats.RESULTS AND CONCLUSIONS:The results do not show an in vivo action of IL-2 on the cholinergic function but are consistent with the probable role of this cytokine in the senescent cognitive impairment, in particular the age-related loss of spatial memory and/or during the evolution of neurodegenerative related process.

NERVE growth factor (NGF) is the best characterized of the neurotrophic factors, but there is incomplete information concerning its levels in body fluids. Normal values of NGF in serum from 157 normal subjects were determined by enzyme immunoassay (EIA). A mean NGF level of 194 ± 25 pg ml−1 was obtained. There were no statistically significant variations with age, but the NGF level was significantly lower in females (112 ± 31 pg ml−1) than in males (243 ± 35 pg ml−1).

We have now applied the enzyme immunoassay using anti-NGF monoclonal antibody (MAb) 27/21 and a blocking test validating the specificity of the immunoreactivity for NGF in serum samples to examine NGF levels in normal rat sera, hemiparkinsonian rat sera, normal monkey sera, and MPTP-treated monkey sera. The levels of NGF in treated animals showed reductions when compared with serum from normal animals. The NGF level alterations observed in lesioned animals and in human parkinsonian patients evidence a relationship between this neurotrophic factor and the neurodegenerative changes observed in Parkinson disease (PD).

Purkinje cells were examined in three familial cases of olivopontocerebellar atrophy (OPCA) by means of the Golgi method, and neurofilament and calcium-binding protein immunocytochemistry. Reduced dendritic arborizations, as seen with different techniques, early formation of axonal spheroids, and abnormal accumulation of phosphorylated neurofilament epitopes in dendrites, somata and axonal spheroids, together with limited formation of proximal spine-like protrusions were the main changes in Purkinje cells. These lesions are unlikely to be the consequence of anterograde degeneration secondary to olivary atrophy, as postulated by some investigators, but probably represent primary damage to Purkinje cells in patients with OPCA. Reduced dendritic arborizations result in a decrease of receptor sites for parallel fibres and deprive granule cells of their main targets. Abnormal accumulation of neurofilaments in somata, dendrites and axonal spheroids may contribute to an abnormal transport and may impair protein turnover in the distal regions of Purkinje cells.

Naturally occurring dead cells in the developing rat neocortex, subcortical white matter and hippocampus, which increase in number during the first postnatal week and decrease thereafter to disappear by the end of the first month, were examined by in situ labeling of nuclear DNA fragmentation. These cells showed peripheral chromatin condensation or extremely dark, often fragmented, nuclei. Southern hybridization following agarose gel electrophoresis of DNA extracted from the developing cortex, but not from adult brain, showed a 'ladder' pattern which is typical of internucleosomal DNA fragmentation. Taken together these results show that naturally occurring cell death (programmed cell death) in the developing cerebral cortex has the morphology of apoptosis and is associated with endonuclease activation.

Cell death in the subicular complex and hippocampus occurs from P0 to P7 in the rat. Dead cells first appear in the subcortical and subammonic plates, and predominate in the border region between the main regional subfields. Cell death in the cellular layers predominates in the subicular complex, CA1 and intermediate region between CA1 and CA3. Dead cells are almost absent in the upper plexiform layers and dentate gyrus.