Cytoarchitecture and cortical connections of the anterior insula and adjacent frontal motor fields in the rhesus monkey.

The cytoarchitecture and cortical connections of the ventral motor region are investigated using Nissl, and NeuN staining methods and the fluorescent retrograde tract tracing technique in the rhesus monkey. On the basis of gradual laminar differentiation, it is shown that the ventral motor region stems from the ventral proisocortical area (anterior insula and dorsal Sylvian opercular region). The cytoarchitecture of the ventral motor region is shown to progress in three lines, as we have recently shown for the dorsal motor region.

Cytoarchitecture and cortical connections of the anterior cingulate and adjacent somatomotor fields in the rhesus monkey.

The cytoarchitecture and cortical connections of the anterior cingulate, medial and dorsal premotor, and precentral region are investigated using the Nissl and NeuN staining methods and the fluorescent retrograde tract tracing technique. There is a gradual stepwise laminar change in the cytoarchitectonic organization from the proisocortical anterior cingulate region, through the lower and upper banks of the cingulate sulcus, to the dorsolateral isocortical premotor and precentral motor regions of the frontal lobe. These changes are characterized by a gradational emphasis on the lower stratum layers (V and VI) in the proisocortical cingulate region to the upper stratum layers (II and III) in the premotor and precentral motor region.

Confocal light absorption and scattering spectroscopic microscopy monitors organelles in live cells with no exogenous labels.

This article reports the development of an optical imaging technique, confocal light absorption and scattering spectroscopic (CLASS) microscopy, capable of noninvasively determining the dimensions and other physical properties of single subcellular organelles. CLASS microscopy combines the principles of light-scattering spectroscopy (LSS) with confocal microscopy. LSS is an optical technique that relates the spectroscopic properties of light elastically scattered by small particles to their size, refractive index, and shape.

Confocal light absorption and scattering spectroscopic microscopy.

We have developed a novel optical method for observing submicrometer intracellular structures in living cells, which is called confocal light absorption and scattering spectroscopic (CLASS) microscopy. It combines confocal microscopy, a well-established high-resolution microscopic technique, with light-scattering spectroscopy. CLASS microscopy requires no exogenous labels and is capable of imaging and continuously monitoring individual viable cells, enabling the observation of cell and organelle functioning at scales of the order of 100 nm.

Caregiver competence to prevent home injury to the care recipient with dementia.

Home safety is a major concern for persons with a progressive dementia, such as Alzheimer's disease, because much direct care is provided in the home setting. This study used the Home Safety/Injury Model as a frame work to describe the domain of caregiver competence, one of the model's key constructs. Interview data from the perspectives of 17 informants yielded a total of 68 clinical situations that allowed exploration of the scope and dimensions of caregiver competence to prevent accidents in the home.

Visual contrast enhances food and liquid intake in advanced Alzheimer's disease.

Background & Aims: Patients with severe Alzheimer's disease (AD) in long-term care have deficient contrast sensitivity and poor food and liquid intake. The present study examined how contrast manipulations affect these intake levels.

Methods: Participants were nine men with advanced AD.

Promoting safer home environments for persons with Alzheimer's disease. The Home Safety/Injury Model.

This article describes a Home Safety/Injury Model derived from Social Cognitive Theory. The model's three components are safety platform, the person with dementia, and risky behaviors. The person with dementia is in the center, located on the safety platform composed of the physical environment and caregiver competence.

Cytoarchitecture and cortical connections of the posterior cingulate and adjacent somatosensory fields in the rhesus monkey.

The cytoarchitecture and connections of the caudal cingulate and medial somatosensory areas were investigated in the rhesus monkey. There is a stepwise laminar differentiation starting from retrosplenial area 30 towards the isocortical regions of the medial parietal cortex. This includes a gradational emphasis on supragranular laminar organization and general reduction of the infragranular neurons as one proceeds from area 30 toward the medial parietal regions, including areas 3, 1, 2, 5, 31, and the supplementary sensory area (SSA).

Facial frequency manipulation normalizes face discrimination in AD.

People with AD have deficient contrast sensitivity and impaired face discrimination. The authors presented photographs of unfamiliar faces of three different sizes to enhance the low, middle, or high facial frequency information (cycles per face). Patients with AD demonstrated normal discrimination of small faces only, indicating that impaired contrast sensitivity at low facial frequencies contributes to their poor face discrimination.

Cortical connections of the frontoparietal opercular areas in the rhesus monkey.

The connections of the frontoparietal opercular areas were studied in rhesus monkeys by using antero- and retrograde tracer techniques. The rostral opercular cortex including the gustatory and proisocortical motor (ProM) areas is connected with precentral areas 3, 1, and 2 as well as with the rostral portion of the opercular area which resembles the second somatosensory type of cortex (area SII) and the ventral portion of area 6. Its distant connections are with the ventral portion of prefrontal areas 46, 11, 12, and 13 as well as with the rostral insula and cingulate motor area (CMAr).

Distribution of inhibitory synapses on the somata of pyramidal neurons in cat motor cortex.

The mechanisms by which cortical neurons perform spatial and temporal integration of synaptic inputs are dependent, in large part, on the numbers, types, and distributions of their synapses. To further our understanding of these integrative mechanisms, we examined the distribution of synapses on identified classes of cortical neurons. Pyramidal cells in the cat motor cortex projecting either to the ipsilateral somatosensory cortex or to the spinal cord were labeled by the retrograde transport of horseradish peroxidase.

Localization of pontine PGO wave generation sites and their anatomical projections in the rat.

A number of experimental and theoretical reports have suggested that the ponto-geniculo-occipital (PGO) wave-generating cells are involved in the generation of rapid eye movement (REM) sleep and REM sleep dependent cognitive functions. No studies to date have examined anatomical projections from PGO-generating cells to those brain structures involved in REM sleep generation and cognitive functions. In the present study, pontine PGO wave-generating sites were mapped by microinjecting carbachol in 74 sites of the rat brainstem.

Persistent vegetative state in Alzheimer disease. Does it exist?

Objective: To determine if the published criteria for diagnosis of the persistent vegetative state could be applied to patients suffering from Alzheimer disease.

Design And Methods: Eighty-eight institutionalized patients with a diagnosis of possible or probable Alzheimer disease were evaluated for the presence of persistent vegetative state. Initial screening excluded patients who were able to do any of the following: feed themselves, respond to command, walk, or maintain continence of bowel and bladder.

Blockade of neuronal nitric oxide synthase protects against excitotoxicity in vivo.

Nitric oxide may be a key mediator of excitotoxic neuronal injury in the central nervous system. We examined the effects of the neuronal nitric oxide synthase inhibitor 7-nitroindazole (7-NI) on excitotoxic striatal lesions. 7-NI significantly attenuated lesions produced by intrastriatal injections of NMDA, but not kainic acid or alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) 7-NI attenuated secondary striatal excitotoxic lesions produced by the succinate dehydrogenase inhibitor malonate, and the protection was reversed by L-arginine but not by D-arginine, 7-NI produced nearly complete protection against striatal lesions produced by systemic administration of 3-nitropropionic acid (3-NP), another succinate dehydrogenase inhibitor, 7-NI protected against malonate induced decreases in ATP, and increases in lactate, as assessed by 1H magnetic resonance spectroscopy.

Involvement of free radicals in excitotoxicity in vivo.

Recent evidence has linked excitotoxicity with the generation of free radicals. We examined whether free radical spin traps can attenuate excitotoxic lesions in vivo. Pretreatment with N-tert-butyl-alpha-(2-sulfophenyl)-nitrone (S-PBN) significantly attenuated striatal excitotoxic lesions in rats produced by N-methyl-D-aspartate (NMDA), kainic acid, and alpha-amino-3-hydroxy-5-methyl-isoxazole-4-propionic acid (AMPA).

Movement disorder following excitotoxin lesions in primates.

We previously reported on the histologic and neurochemical features of quinolinic acid lesions in primates which produce many of the characteristic features of Huntington's disease (HD). We now report on the effects of apomorphine in generating a movement disorder in four of these animals. Animals were tested with saline or apomorphine both before and after the lesions.

Excitotoxin lesions in primates as a model for Huntington's disease: histopathologic and neurochemical characterization.

Excitotoxin lesions induced by quinolinic acid (QA) were made unilaterally in the caudate nucleus and putamen of 12 rhesus monkeys. Both acute (2-3 weeks) and chronic (4-6 months) effects were evaluated. Excitotoxin striatal lesions were characterized by a central zone of intense astrogliosis and marked neuronal depletion, which was surrounded by a transition zone in which there was partial neuronal sparing throughout the entire lesioned side.

Immunogenicity of a recombinant hepatitis B vaccine in hemodialysis patients: a two-year follow-up.

The immunogenicity of a recombinant hepatitis B vaccine was evaluated in 35 hemodialysis patients who received a standard dose (20 micrograms) of the vaccine at 0, 1, 2 and 6 months. After the full vaccination course (month 7), 60% (21/35) of the patients had seroconverted (anti-HBs titer greater than or equal to 10 mIU/ml). The duration of protection lasted up to 18 months after the start of vaccination in 85.

Golgi, histochemical, and immunocytochemical analyses of the neurons of auditory-related cortices of the rhesus monkey.

Morphological characteristics of the neurons of the auditory cortical areas of the rhesus monkey were investigated using Golgi and horseradish peroxidase methods. Neurons of the auditory cortices can be segregated into two categories, spinous and nonspinous, which can be further subclassified according to their dendritic arrays. The spinous neurons include pyramidal, "star pyramid," multipolar, and bipolar cells.

Immune response to a recombinant hepatitis B vaccine in hemodialysis patients.

A 20-microgram dose of a recombinant hepatitis B vaccine was given at 0, 1, 2 and 6 months to 24 hemodialysis patients. From month 7 (i.e.

Neurons of the lateral entorhinal cortex of the rhesus monkey: a Golgi, histochemical, and immunocytochemical characterization.

This study identifies the neuronal types of the rhesus monkey lateral entorhinal cortex (LEC) and discusses the importance of these data in the context of the connectional patterns of the LEC and the possible role of these cells in neurodegenerative diseases. These neuronal types were characterized with the aid of Golgi impregnation techniques. These characterizations were based upon their spine densities, dendritic arrays, and, where possible, axonal arborizations.

Thalamocortical synapses with identified neurons in monkey primary auditory cortex: a combined Golgi/EM and GABA/peptide immunocytochemistry study.

The objective of this study was to identify neurons in layer IV of the monkey primary auditory cortex (area KA) that are postsynaptic to thalamocortical axon terminals. Thalamocortical axon terminals were labeled by lesion-induced degeneration; neurons postsynaptic to these afferents were labeled by the Golgi/EM method followed by postembedding immunocytochemistry. Five of the six non-pyramidal neurons examined received synapses from thalamocortical axon terminals.

Connectional analysis of the ipsilateral and contralateral afferent neurons of the superior temporal region in the rhesus monkey.

The interhemispheric and ipsilateral afferents of the superior temporal region (STR) were investigated with the aid of fluorescent retrograde tracers (Diamidino Yellow and Fast Blue). Different tracers were injected in selected cortical areas of the STR of each hemisphere of four rhesus monkeys. The results show that the interhemispheric afferents originate not only from the homotopic but also from heterotopic areas.

The identification of thalamocortical axon terminals in barrels of mouse Sml cortex using immunohistochemistry of anterogradely transported lectin (Phaseolus vulgaris-leucoagglutinin).

The anterograde transport and immunohistochemical demonstration of the lectin, Phaseolus vulgaris-leucoagglutinin (PHA-L) has been used to label thalamocortical axon terminals in barrels of mouse SmI cortex. The reaction product is visible with both the light and electron microscopes so that the distribution of axons and the types of synapses they form can be determined.

The use of lectin transport in the mouse central nervous system as an anterograde axonal marker for electron microscopy.

Lesion-induced axonal degeneration and autoradiography-electron microscopy have been the only reliable anterograde axonal markers available for electron microscopic examination of neuronal circuitry. However, these methods have their limitations. Recently, Phaseolus vulgaris-leucoagglutinin (PHA-L) has been used as an anterograde axonal marker for light microscopy.