Cytokine mRNA expression in postischemic/reperfused myocardium.

While the role of cytokines in mediating injury during hind limb skeletal muscle ischemia followed by reperfusion has recently been described, the role of cytokines in myocardial infarction and ischemia/reperfusion have remained relatively unexplored. We hypothesize that cytokines play an important role in the regulation of postischemic myocardial inflammation. This study reports the temporal sequence of proinflammatory cytokine gene expression in postischemic/reperfused myocardium and localizes interleukin-1 beta (IL-1 beta) and tumor necrosis factor-alpha (TNF-alpha)-protein by immunostaining.

Induction of nitric oxide synthase in demyelinating regions of multiple sclerosis brains.

The amount of messenger RNA encoding human inducible nitric oxide synthase and the presence and distribution of NADPH diaphorase were determined in tissue sections from multiple sclerosis (MS) and control brains. Levels of human nitric oxide synthase messenger RNA were markedly elevated in MS brains when compared to normal control brains. NADPH diaphorase activity, a histochemical stain reflecting nitric oxide synthase catalytic activity, was detected in reactive astrocytes in active demyelinating MS lesions and at the edge of chronic active demyelinating lesions.

Elevated central nervous system prostaglandins in human immunodeficiency virus-associated dementia.

The dementia associated with human immunodeficiency virus (HIV) is poorly understood. Dementia is accompanied by infection and activation of macrophage lineage cells in the brain and production of toxic products by these cells has been postulated to play a role in the pathogenesis of dementia. Eicosanoids are potential products of activated macrophages that can mediate cell injury.

Intracerebral cytokine mRNA expression during fatal and nonfatal alphavirus encephalitis suggests a predominant type 2 T cell response.

Sindbis virus (SV) causes an acute encephalomyelitis in mice. A T cell-dependent inflammatory response is first detected 3 days after infection and includes T cells, B cells, and macrophages. The cytokines produced locally by intrinsic cells of the brain in response to infection and by infiltrating mononuclear cells and their contributions to outcome of infection have not been identified.

Cytokine dysregulation in HIV-associated neurological disease.

AIDS is associated with three major neurological syndromes: dementia (HIVD), vacuolar myelopathy (VM) and plainful sensory neuropathy (PSN). The pathogenesis of these conditions remains unclear although they all demonstrate a marked increase in macrophage number and activation despite systemic immunosuppression. It was therefore of interest to determine the profile of cytokine and HIV expression in brain, spinal cord and peripheral nerves of AIDS patients with AD, VM and PSN, as compared to AIDS patients without neurological disease and seronegative controls.

Clinical-neuropathologic correlation in HIV-associated dementia.

The structural abnormalities that correlate with the clinical manifestations of HIV-associated dementia (HIVD) are unclear. In a prospectively categorized group of patients with and without HIVD who were followed to autopsy, we correlated HIV-related neuropathologic changes with the presence and severity of HIVD. We also assessed the effect of antiretroviral therapy on the neuropathologic changes.

Cerebral white matter changes in acquired immunodeficiency syndrome dementia: alterations of the blood-brain barrier.

The cause of acquired immunodeficiency syndrome (AIDS) dementia, which is a frequent late manifestation of human immunodeficiency virus (HIV) infection, is unknown but radiological and pathological studies have implicated alterations in subcortical white matter. To investigate the pathological basis of these white matter abnormalities, we performed an immunocytochemical and histological analysis of subcortical white matter from AIDS patients with and without dementia, from pre-AIDS patients (asymptomatic HIV-seropositive patients), and from HIV-seronegative control subjects. Reduced intensity of Luxol fast blue staining, designated "diffuse myelin pallor," was detected in 8 of 15 AIDS dementia patients, 3 of 13 AIDS nondemented patients, and none of the pre-AIDS patients (n = 2) or control subjects (n = 9).

Intracerebral cytokine messenger RNA expression in acquired immunodeficiency syndrome dementia.

The pathogenesis of the dementia associated with human immunodeficiency virus (HIV) infection is unclear, but has been postulated to be due to indirect effects of HIV infection including the local production of cytokines. To determine which cytokines are produced in the nervous system and to identify any correlations with dementia, cytokine and HIV messenger RNA expression was analyzed by reverse transcriptase-polymerase chain reaction in the brains from 24 HIV-infected patients with and without dementia and 9 HIV-uninfected control subjects. Levels of tumor necrosis factor-alpha messenger RNA were significantly higher and levels of interleukin (IL)-4 messenger RNA were significantly lower in demented compared to nondemented HIV-infected patients.

Renal sympathetic preganglionic neurons demonstrated by herpes simplex virus transneuronal labelling in the rabbit: close apposition of neuropeptide Y-immunoreactive terminals.

Renal sympathetic preganglionic neurons in the spinal cord of rabbits were transneuronally retrogradely labelled by injection of Herpes simplex virus type 1 into the renal nerve and immunohistochemical demonstration of viral antigen. The morphology of the labelled neurons was examined, particularly with respect to the shape and extent of their dendritic trees. Double-labelling immunohistochemical studies were performed to determine the relationship of neuropeptide Y-immunoreactive axons to virus-labelled perikarya and dendrites.

Transneuronal labelling of neurons in rabbit brain after injection of herpes simplex virus type 1 into the renal nerve.

We mapped the distribution of virus-labelled neurons in the brain after injection of Herpes simplex virus type 1 (HSV1) into the rabbit renal nerve. Seven days after injection, labelled neurons were observed in four brain regions, the rostral ventrolateral medulla (47 +/- 3% of neurons), the A5 area of the lower pons (38 +/- 4%), the caudal raphe nuclei and the parapyramidal area of the medulla (13 +/- 2%), and the paraventricular nucleus of the hypothalamus (1 +/- 1%). In the rostral ventrolateral medulla approximately one half of the HSV1-labelled neurons also contained tyrosine hydroxylase, characterizing them as C1 neurons.

Long term intraparenchymal Ig secretion after acute viral encephalitis in mice.

Oligoclonal bands in the cerebrospinal fluid indicate intrathecal synthesis of Ig of restricted heterogeneity and are associated with a number of central nervous system inflammatory diseases. To gain better insight into the persistence of oligoclonal bands found in the central nervous system we studied mice infected with Sindbis virus (SV), a RNA virus that causes an acute, nonfatal encephalitis in mice. SV was inoculated intracerebrally into weanling mice and brains and spleens were harvested at various time points long after the acute encephalitis had resolved.

Development of an enzyme immunoassay to detect antibody to Chlamydia pneumoniae strain TWAR and its application in a limited seroepidemiological survey.

A non-competitive enzyme immunoassay (EIA) was developed to detect IgG antibody to the recently-described species Chlamydia pneumoniae strain TWAR. Purified elementary bodies of the organism were used as capture antigen. Cross-reacting antibody to Chlamydia trachomatis was detected in the assay by running a parallel EIA for IgG antibody to C.

Projections from rabbit caudal medulla to C1 and A5 sympathetic premotor neurons, demonstrated with phaseolus leucoagglutinin and herpes simplex virus.

We combined Phaseolus vulgaris leucoagglutinin anterograde tracing and Herpes simplex virus transneuronal retrograde tracing to determine whether neurons in the vasodepressor region of the rabbit caudal ventrolateral medulla project to brainstem neurons containing the virus after its transneuronal transport from the adrenal medulla. Five days after adrenal injection of virus, 764 +/- 159 virus-positive neurons were found bilaterally in the brainstem: 61% in the C1 sympathoexcitatory region of the rostral ventrolateral medulla, 30% in the A5 region, 5% in the parapyramidal region, and 3% in the paraventricular nucleus of the hypothalamus. Many of the virus-positive neurons in the C1 and A5 areas also contained tyrosine hydroxylase and, in the parapyramidal area, many contained 5-hydroxytryptamine.

Renal and adrenal sympathetic preganglionic neurons in rabbit spinal cord: tracing with herpes simplex virus.

We mapped sympathetic renal preganglionic neurons in the rabbit spinal cord using Herpes simplex virus retrograde transneuronal tracing after application of the virus to the renal nerve. Virus-positive neurons were found in the spinal cord from T7 to L2, principally in the ipsilateral intermediolateral cell column. Renal and adrenal preganglionic neurons are largely separate populations.

Human astrocytes express membrane cofactor protein (CD46), a regulator of complement activation.

Expression of membrane cofactor protein (CD46) on cultured human astrocytes was demonstrated by indirect immunofluorescence microscopy and flow cytometry following staining with a monoclonal antibody specific for CD46. Western transfer and immunoblotting detected a doublet of Mr 66,000 and 56,000. Analysis of astrocyte mRNA revealed the presence of multiple alternatively spliced transcripts encoding different extracellular regions or cytoplasmic tails of CD46.

Transneuronal labeling of neurons in rabbit brain after injection of herpes simplex virus type 1 into the aortic depressor nerve.

Herpes simplex virus type 1 (HSV1) was injected into either the aortic depressor nerve or the vagus nerve in the rabbit. Four or 5 days after injection of virus, the rabbit brain was processed immunohistochemically to demonstrate viral antigen. After injection into the aortic nerve HSV1 positive cells were found principally ipsilaterally within the nucleus tractus solitarius, area postrema, caudal and rostral ventrolateral medulla oblongata, the spinal trigeminal complex, raphe nuclei, A5 area, locus coeruleus, parabrachial nucleus, periaqueductal gray, ventrolateral hypothalamic area, paraventricular nucleus, amygdala, bed nucleus of the stria terminalis and insular cortex.

Transneuronal transport of herpes simplex virus from the cervical vagus to brain neurons with axonal inputs to central vagal sensory nuclei in the rat.

The recent introduction of live viruses as intra-axonal tracing agents has raised questions concerning which central neurons are transneuronally labelled after application of the virus to peripheral organs or peripheral nerves. Since the central connections of the vagus nerve have been well described using conventional neuronal tracing agents, we chose to inject Herpes Simplex Virus Type 1 into the cervical vagus of the rat. After survival times of up to 3 days the rat brains were processed immunohistochemically using a polyclonal antiserum against herpes simplex virus.

Detection of cytokine mRNA in astrocyte cultures using the polymerase chain reaction.

To clarify which cytokines could potentially be produced by astrocytes, we have assessed the presence of mRNA for a number of cytokines in astrocyte-enriched brain cultures. The cultures were derived from neonatal murine brain and were treated with either interferon-gamma, lipopolysaccharide or tumor necrosis factor-alpha, or infected with murine cytomegalovirus. RNA was extracted at 0, 4, 24 and 48 hours post treatment.

PNMT-containing neurons in the rostral medulla oblongata (C1, C3 groups) are transneuronally labelled after injection of herpes simplex virus type 1 into the adrenal gland.

Herpes simplex virus type 1 (HSV1) was injected into the rat adrenal gland. After 3 days the rat CNS was processed immunohistochemically to demonstrate viral antigen. In the lower thoracic spinal cord viral antigen was found in neurons in the intermediolateral column.

Fibrocalculous pancreatic diabetes in Papua New Guinea.

While fibrocalculous pancreatic diabetes (FCPD) has long been recognized in neighboring Indonesia, there has been only one single case reported from Papua New Guinea. Over an eighteen month period, four new cases of FCPD were seen at this hospital, making FCPD the predominant form of diabetes seen in Papua New Guinea highlanders. Abdominal pain was prominent in only one patient.