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Aging is a major risk factor for cerebral infarction. Since cellular senescence is intrinsic to aging, we postulated that stroke-induced cellular senescence might contribute to neural dysfunction. Adult male Wistar rats underwent 60-minute middle cerebral artery occlusion and were grouped according to 3 reperfusion times: 24 hours, 3, and 7 days. The major biomarkers of senescence: 1) accumulation of the lysosomal pigment, lipofuscin; 2) expression of the cell cycle arrest markers p21, p53, and p16INK4a; and 3) expression of the senescence-associated secretory phenotype cytokines interleukin-6 (IL-6), tumor necrosis factor α (TNF-α), and interleukin-1β (IL-1β) were investigated in brain samples. Lipofuscin accumulation was scarce at the initial stage of brain damage (24 hours), but progressively increased until it reached massive distribution at 7 days post-ischemia. Lipofuscin granules (aggresomes) were mainly confined to the infarcted areas, that is parietal cortex and adjacent caudate-putamen, which were equally affected. The expression of p21, p53, and p16INK4a, and that of IL-6, TNF-α, and IL-1β, was significantly higher in the ischemic hemisphere than in the non-ischemic hemisphere. These data indicate that brain cell senescence develops during acute ischemic infarction and suggest that the acute treatment of ischemic stroke might be enhanced using senolytic drugs., (© The Author(s) 2022. Published by Oxford University Press on behalf of American Association of Neuropathologists, Inc. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

In this study, we evaluated homeostatic and functional disorders of the spleen in mice inoculated with Toxoplasma gondii. The kinetics of megakaryocyte and leukocyte production, body and spleen mass and certain histopathological aspects were analyzed. There was increased (P < 0.05) the accumulation of lipofuscin in the red pulp of the spleen, in the periods of 30 and 60 dpi of the infection, that is, in the chronification stage of the disease and decrease of the white pulp area. In addition, we observed (from 7dpi) a quantitative and qualitative increase (P < 0.05) in the deposition of collagen fibers in the spleen of all infected mice. Since resolution of the inflammatory process resulted in pathophysiological changes, we can suggest that the T. gondii invaded and multiplied in the cells of the white and red pulps of the spleen. Although we did not find the parasite in the spleen, this hypothesis is supported by the presence of diffuse inflammatory infiltrate, which extended through the spleen parenchyma of all inoculated mice. Taken together, our results suggest that T. gondii causes severe homeostatic disorders that have altered spleen physiology, including diffuse parenchymal inflammation, lipofuscinosis in histiocytes, early aging, collagenopathy, systemic sclerosis and spleen and white pulp atrophy., (© FEMS 2020.)

Objectives: This study was conducted to evaluate the longevity potential of damaurone D (DaD), a component of the damask rose, in the animal model Caenorhabditis elegans., Methods: To investigate the effect of DaD on the longevity, lifespan assay was carried out. Fluorescence intensity of transgenic mutants was quantified to test the expression levels of stress proteins. A genetic study using single gene knockout mutants was designed to determine the target genes of DaD., Key Findings: DaD prolonged the mean lifespan of wild-type nematodes by 16.7% under normal conditions and also improved their stress endurance under thermal, osmotic, and oxidative stress conditions. This longevity-promoting effect could be attributed to in vivo antioxidant capacity and its up-regulating effects on the expressions of stress-response proteins such as SOD-3 and HSP-16.2. In addition, DaD treatment attenuated food intake, body length, lipofuscin accumulation and age-dependent decline of motor ability. Gene-specific mutant studies showed the involvement of genes such as daf-2, age-1, and daf-16., Conclusions: These results suggest that DaD has beneficial effects on the longevity, and thus it can be a valuable plant origin lead compound for the development of nutraceutical preparations targeting ageing and ageing-related diseases., (© 2018 Royal Pharmaceutical Society.)

Study Objectives: Intermittent short sleep (ISS) is pervasive among students and workers in modern societies, yet the lasting consequences of repeated short sleep on behavior and brain health are largely unexplored. Wake-activated neurons may be at increased risk of metabolic injury across sustained wakefulness., Methods: To examine the effects of ISS on wake-activated neurons and wake behavior, wild-type mice were randomized to ISS (a repeated pattern of short sleep on 3 consecutive days followed by 4 days of recovery sleep for 4 weeks) or rested control conditions. Subsets of both groups were allowed a recovery period consisting of 4-week unperturbed activity in home cages with littermates. Mice were examined for immediate and delayed (following recovery) effects of ISS on wake neuron cell metabolics, cell counts, and sleep/wake patterns., Results: ISS resulted in sustained disruption of sleep/wake activity, with increased wakefulness during the lights-on period and reduced wake bout duration and wake time during the lights-off period. Noradrenergic locus coeruleus (LC) and orexinergic neurons showed persistent alterations in morphology, and reductions in both neuronal stereological cell counts and fronto-cortical projections. Surviving wake-activated neurons evidenced persistent reductions in sirtuins 1 and 3 and increased lipofuscin. In contrast, ISS resulted in no lasting injury to the sleep-activated melanin concentrating hormone neurons., Conclusions: Collectively these findings demonstrate for the first time that ISS imparts significant lasting disturbances in sleep/wake activity, degeneration of wake-activated LC and orexinergic neurons, and lasting metabolic changes in remaining neurons most consistent with premature senescence., (© 2016 Associated Professional Sleep Societies, LLC.)

Objective: To investigate the neuroprotective effects of saponins from Panax japonicus (SPJ) on D-galactose (D-gal)-induced brain ageing, and further explore the underlying mechanisms., Methods: SPJ were analysed using high-pressure liquid chromatography. Male Wistar rats weighing 200 ± 20 g were randomly divided into four groups: control group (saline), D-gal-treated group (400 mg/kg, subcutaneously), D-gal + SPJ groups (50, 100 and 200 mg/kg, orally) and vitamin E group (100 mg/kg). Rats were injected corresponding drugs once daily for 8 weeks. Neuroprotective effects of SPJ were evaluated by Morris water maze, histopathological observations, biochemical assays, western blot analysis and quantitative real-time polymerase chain reaction (PCR) analysis in vivo as well as reactive oxygen species (ROS) measurement and apoptosis assay in vitro., Key Findings: Our present study showed that D-gal had a neurotoxic effect in rats and in SH-SY5Y cells due to oxidative stress induction, including decreased total anti-oxidant capacity, superoxide dismutase (SOD) and glutathione peroxidase activity, ultimately leading to spatial learning and memory impairment in rats and ROS accumulation in SH-SY5Y cells. SPJ improved spatial learning and memory deficits, attenuated hippocampus histopathological injury and restored impaired anti-oxidative as well as anti-apoptotic capacities in D-gal-induced ageing rats. In addition, SPJ remarkably decreased lipofuscin levels, increased hippocampus nuclear factor erythroid 2-related factor 2 (Nrf2) and silent mating type information regulation 2 homologue (SIRT1) protein levels and anti-oxidant genes expression such as manganese superoxide dismutase (Mn-SOD), heme oxygenase (HO-1), NAD(P)H quinone oxidoreductase 1 (NQO1) and cysteine ligase catalytic (GCLC) in D-gal-induced brain ageing., Conclusions: Our data suggested that D-gal induced multiple molecular and functional changes in brain similar to natural ageing process. SPJ protected brain from D-gal-induced neuronal injury through decreasing oxidative stress and apoptosis, and ultimately improving cognitive performance in D-gal-induced brain ageing. It is possibly related to Nrf2 and SIRT1-mediated anti-oxidant signalling pathways., (© 2015 Royal Pharmaceutical Society.)

Long Evans rats were treated by a low-Zinc-Diet (ZD) and the ultrastructure and elemental composition of melanosomes of the RPE and choroidal melanocytes and RPE lipofuscin granules were investigated using Analytical Electron Microscopy (AEM). In controls the Zn mole fraction of melanosomes was 0.05 at% (RPE) and 0.06 at% (choroid), respectively. For ZD-rats the Zn mole fraction of these granules was almost unchanged in the choroid but decreased and was below the detection limit (0.02 at%) in the RPE. ZD-rats produced also giant melanosomes (diameter 1-3 μm) in the choroid and greatly increased amounts of RPE lipofuscin. The giant melanosomes contained about six times as much Cu as control melanosomes. Lipofuscin granules were identified by AEM and could be clearly distinguished from melanosomes by their chemical composition. Thus, changes of the ultrastructure and transition metal storage of melanosomes due to a ZD can be directly traced using AEM., (This journal is © The Royal Society of Chemistry 2012)

Mitochondrial abnormalities are prominent in Alzheimer disease. In this study, 2 mitochondrial markers, cytochrome oxidase-1 and lipoic acid, a sulfur-containing cofactor required for the activity of several mitochondrial enzyme complexes, were compared using light and electron microscopic analyses and immunoblot assays. Both lipoic acid and cytochrome oxidase-1 immunoreactivity are increased in the cytoplasm of pyramidal neurons in Alzheimer disease compared with control cases. Of significance, lipoic acid was found to be strongly associated with granular structures, and ultrastructure analysis showed localization to mitochondria, cytosol, and, importantly, in organelles identified as autophagic vacuoles and lipofuscin in Alzheimer disease but not control cases. Cytochrome oxidase-1 immunoreactivity was limited to mitochondria and cytosol in both Alzheimer and control cases. These data suggest that mitochondria are key targets of increased autophagic degradation in Alzheimer disease. Whether increased autophagocytosis is a consequence of an increased turnover of mitochondria or whether the mitochondria in Alzheimer disease are more susceptible to autophagy remains to be resolved.

IGF action has been implicated in the promotion of oxidative stress and aging in invertebrate and murine models. However, some in vitro models suggest that IGF-I specifically prevents neuronal oxidative damage. To investigate whether IGF-I promotes or retards brain aging, we evaluated signs of oxidative stress and neuropathological aging in brains from 400-d-old Igf1-/- and wild-type (WT) mice. Lipofuscin pigment accumulation reflects oxidative stress and aging, but we found no difference in lipofuscin deposition in Igf1-/- and WT brains. Likewise, there was no apparent difference in accumulation of nitrotyrosine residues in Igf1-/- and WT brains, except for layer IV/V of the cerebral cortex, where these proteins were about 20% higher in the Igf1-/- brain (P = 0.03). We found no difference in the levels of oxidative stress-related enzymes, neuronal nitric oxide synthase, inducible nitric oxide synthase, and superoxide dismutase in Igf1-/- and WT brains. Tau is a microtubule-associated protein that causes the formation of neurofibrillary tangles and senile plaques as it becomes hyperphosphorylated in the aging brain. Tau phosphorylation was dramatically increased on two specific residues, Ser-396 and Ser-202, both glycogen synthase kinases target sites implicated in neurodegeneration. These observations indicate that IGF-I has a major role in regulating tau phosphorylation in the aging brain, whereas its role in promoting or preventing oxidative stress remains uncertain.

Aims: In a previous study, we found that prolonged oxidative stress produced by chronic ethanol consumption leads to an increased formation of lipofuscin in hippocampal and cerebellar neurons. This pigment is an end-result of lipid peroxidation. Flavanols, which abound in the human diet, are known to exert a powerful in-vitro antioxidant action. Therefore, to evaluate whether these compounds might display beneficial effects in the rat brain, we examined whether or not these natural antioxidants would impede neuronal ethanol-induced lipofuscin accumulation., Methods: Adult rats were fed for 6 months either with 20% ethanol solution or with the same solution to which a mixture of grape seed catechins and oligomeric procyanidins (200 mg/l) was added. Controls ingested either tap water or water supplemented with the antioxidant compound. The total amount of lipofuscin in the hippocampal CA1 and CA3 pyramids and in the cerebellar Purkinje cells was estimated by applying unbiased stereological methods. The mean volume of the neurons was estimated using the nucleator and the volumetric density of lipofuscin was calculated by point counting., Results: Flavanols prevented the accumulation of neuronal lipofuscin in the animals submitted to ethanol feeding (i.e. under conditions of increased oxidative stress) but not in the water-drinking controls. The neuronal volume did not alter among the groups studied., Conclusions: Data obtained show that consumption of flavanols can reduce the effects of oxidative activity brought about by alcohol consumption, indicating that these compounds might display neuronal beneficial effects under oxidative stress.

The accumulation of the autofluorescent pigment lipofuscin in the retina that occurs with aging has been explained as a side effect of the visual cycle. It occurs when two molecules of all-trans-retinal condense with one molecule of phosphatidylethanolamine in the discs of the rod outer segments, and is followed by uptake into retinal pigment epithelium (RPE) and conversion to the stable A2E, a pyridinium bisretinoid that is toxic to RPE cells. The accumulation of A2E, the major component of lipofuscin causes RPE cell apoptosis, thereby explaining age-related macular degeneration and macular degeneration characteristic of Stargardt disease. The drug isotretinoin (13-cis-retinoic acid) prevents accumulation of A2E in mice by slowing down the visual cycle and might therefore be used to prevent macular degeneration.

Glial lipopigment appears in the globus pallidus without accumulating in neurons (except for late adolescence) in multiple chronic childhood diseases. In this observational study, we compared the age-related development of glial pigmentation in children with the chronic illness (cystic fibrosis) and children dying acutely. A secondary goal was to search for pallidal neuronal lipopigment in childhood. We recorded pigmentation in the brains of 37 consecutive cystic fibrosis children ranging in age from 0-23 yr and in 17 controls ranging in age from 0-18 yr. We characterized the lipofuscin histochemically and used several regression models to describe the mode of deposition. We observed that in the controls, intraglial pallidal pigment accumulated in 2 forms (relatively large globules and, separately, as clusters of fine granules) at a slow rate during childhood. In cystic fibrosis, both forms of pallidal glial pigment started accumulating at a younger age and were deposited far more rapidly. There was a further increase in the rate of accumulation between 8 and 10 yr of age. We did not encounter pallidal neuronal lipofuscin at any age. These observations are consistent with 2 propositions: 1) that globus pallidus glial cells are unique in their ability to accumulate lipofuscin before it accumulates in nearby neurons; and 2) that they are particularly susceptible to some systemic effect of this chronic illness.

Reactive plasticity, including axonal and dendritic sprouting and reactive synaptogenesis, has been proposed to contribute to the pathogenesis of several neurological disorders. This work was aimed at identifying the possible role of protein glycosylation in the brain from patients with Alzheimer disease (AD), using lectin histochemistry, as determinants of reactive plasticity. Results indicate an increase in the production of cryptic O-glycosidically linked proteins (NeuAcalpha2,6 Galbeta1,3GalNAcalpha1,0 Ser/Thr or sialyl-T-antigen) in neuritic sprouting in AD brains as determined by positive labeling with Amaranthus leucocarpus (ALL, T-antigen-specific) and Macrobrachium rosenbergii (MRL, specific for NeuAc5,9Ac2) lectins. Immunohistochemistry indicated that lectin staining was specific for the synaptic sprouting process (meganeurites) in AD. These results were confirmed using anti-synaptophysin and anti-GAP 43 antibodies, which recognized meganeurites and dystrophic neurites around amyloid-beta deposits. In normal control brains, labeling with the aforementioned lectins was restricted to microvessels. Control experiments with neuraminidase-treated brain samples revealed positivity to the lectin from Arachis hypogaea (PNA), which is specific for galactose. Our results suggest specific O-glycosylation patterns of proteins closely related to neuronal plasticity in AD.

A wide variety of anatomic and histological alterations are common in brains of aged individuals. However, identification of intrinsic aging changes--as distinct from changes resulting from cumulative environmental insult--is problematic. Some degree of neuronal and volume loss would appear to be inevitable, but recent studies have suggested that the magnitudes of such changes are much less than previously thought, and studies of dendritic complexity in cognitively intact individuals suggest continuing neuronal plasticity into the eighth decade. A number of vascular changes become more frequent with age, many attributable to systemic conditions such as hypertension and atherosclerosis. Age-associated vascular changes not clearly linked to such conditions include hyaline arteriosclerotic changes with formation of arterial tortuosities in small intracranial vessels and the radiographic changes in deep cerebral white matter known as "leukoaraiosis." Aging is accompanied by increases in glial cell activation, in oxidative damage to proteins and lipids, in irreversible protein glycation, and in damage to DNA, and such changes may underlie in part the age-associated increasing incidence of "degenerative" conditions such as Alzheimer disease and Parkinson disease. A small number of histological changes appear to be universal in aged human brains. These include increasing numbers of corpora amylacea within astrocytic processes near blood-brain or cerebrospinal fluid-brain interfaces, accumulation of the "aging" pigment lipofuscin in all brain regions, and appearance of Alzheimer-type neurofibrillary tangles (but not necessarily amyloid plaques) in mesial temporal structures.

The adrenal cortexes of humans and rodents accumulate lipofuscin with age, but the chemical nature of the substance that produces lipofuscin fluorescence in the gland is not known. Analysis of rat adrenal nonpolar lipids revealed a fluorescence profile with increased intensity in the lipids extracted from older animals (23-24 months > 6 months > 6 weeks). The peak occurred at a wavelength of 470 +/- 5 nm(n = 26) when excited at 340 nm. After sucrose density gradient centrifugation, the fluorescent substance was primarily concentrated in subcellular lipid droplets rather than supernatant or particulate. Prolonged stimulation of rats with ACTH for 7 consecutive days caused 14-51% decreases in the fluorescence levels, with a tendency of return to control levels poststimulation regardless of age. In contrast, the nonpolar lipids of mouse adrenal tumor (Y1) cells, which contain no lipofuscin, did not display this fluorescence in the presence or absence of ACTH. The chromatographic characteristics of the substance in a silica gel-60 column resembled those of authentic retinyl palmitate and cholesteryl oleate. Analysis of the substance by HPLC demonstrated at least three prominent peaks, designated XI-3 in order. X1 and X2 were minor peaks; X3 was the major peak. Whereas none of the peaks comigrated with cholesteryl esters, X1 comigrated with authentic retinyl palmitate. Determination of the fatty acid component of the major fluorescent substance X3 by gas-liquid chromatography disclosed stearic acid. Retinyl stearate was, therefore, synthesized. The fluorescent profiles, HPLC retention time and mass spectrometric fragmentation of purified X3 substance were all identical to those of the synthetic compound. In contrast, the rat liver principally accumulated retinyl palmitate with age. Thus, we conclude that 1) the major nonpolar fluorescent substance accumulated in the rat adrenal with age is retinyl stearate, which may be a fluorophore of adrenal lipofuscin; 2) ACTH action may be related to this accumulation; and 3) the type of retinyl ester accumulated in aged animals is organ specific.

The myocardial interactions of ageing and lifelong ethanol ingestion were studied in the ethanol-preferring AA (Alko Alcohol) line of rats. Samples of the left ventricle from young control rats (3-month), old control rats (30-month) and rats exposed to ethanol from 3 to 30 months of age, were studied in terms of myocardial ultrastructure and lipopigmentation. Electron microscopic morphometry showed an age-related increase in the volumetric densities of lipofuscin and unspecified sarcoplasm, while the proportions of mitochondria, myofibrils and tubular structures remained unaltered in the left ventricular myocardium. Lifelong ethanol exposure increased the proportion of sarcoplasmic reticulum and transverse tubules, apparently due to dilation of the tubular structures. Mitochondria were significantly larger in the ethanol-exposed rats compared to the control rats of the same age, while the volumetric proportion of mitochondria tended to decrease in the ethanol-exposed group. Fluorescence microscopic image analysis showed that myocardial lipopigmentation (proportion of myocardial area covered by autofluorescent lipopigments) was about two-fold in the old ethanol-exposed rats compared to the old control rats, and 13-fold compared to the young controls. It is concluded that ageing and chronic ethanol ingestion produce rather different patterns of alteration in myocardial ultrastructure, which does not support the concept of ethanol-induced accelerated ageing. The enhancement of myocardial lipofuscin accumulation is thought to reflect chronic oxidative stress in the hearts exposed to ethanol.

The amount and distribution of myocardial lipopigments ('age pigments') were studied in alcoholic and control human hearts, to test the hypothesis of ethanol-induced long-term oxidative damage in myocardium. The amount of myocardial lipopigments was measured by image analysis in six men (age 34-60 years) who had a history of chronic alcohol misuse and who died of acute ethanol intoxication, and in their age-matched, non-alcoholic controls. Lipopigmentation in the intoxication cases was 33.5 +/- 2.8% (mean +/- SEM) higher compared to the controls in the eight myocardial areas studied (P < 0.001). A linear correlation of myocardial lipopigmentation with age was noticed in both the intoxication group (R = 0.894) and the controls (R = 0.927). The amount of lipopigments varied largely from one myocardial area to another, being highest in the most strained areas (left ventricle, interventricular septum). The accumulation of lipopigments is considered a marker of oxidative stress and ageing in the myocardium. The results support the role of free radical-induced oxidative stress in the pathogenesis of ethanol-induced cardiac abnormalities.

Lipofuscin is the fluorescent mixture of compounds that accumulates increasingly with age in human tissues, including the pigment epithelium of the retina. A substantial component of lipofuscin has been identified in the retina as N-retinylidene-N-retinylethanolamine. This compound presumably is derived from the reaction of retinaldehyde with the membrane lipid phosphatidylethanolamine.

The acute effects of increasing doses of sodium iodide were studied on human thyroid follicles isolated from normal paranodular tissue. After 24 h incubation in culture medium, follicles isolated from most thyroids maintained their capacity for 125I accumulation and organification and a normal cellular ultrastructure. 125I accumulation was significantly increased after addition of TSH, whereas 125I organification was not affected. In presence of TSH, numerous follicles had large empty-looking follicular lumina unlabeled on autoradiographies. Follicles incubated for 24 h in the presence of a low concentration (10(-7) M) of iodide retained their function and morphology. However, incubation with a high dose of iodide (10(-3) M) caused marked inhibition of 125I accumulation and organification reaching values similar to those obtained in presence of inhibitors of iodide trapping and organification. At high doses, iodide induced necrosis of thyroid epithelial cells: the percentage of necrotic cells was significantly increased with 10(-5) M and doubled with 10(-3) M as compared to values measured at 10(-7) M. Ultrastructural lesions such as apical blebbing, cytoplasmic fragments desquamation, endoplasmic reticulum vesiculation, and accumulation of lipofuscin in secondary lysosomes were also present. The necrotic effect and the ultrastructural alterations also occurred in the presence of TSH but were prevented by the addition of inhibitors of iodide trapping or organification. These results demonstrate a direct acute toxic effect of iodide in human thyroid cells. The nature of the ultrastructural alterations is in agreement with a mechanism of toxicity involving a free radical attack and lipid peroxidation as observed in other tissues.

The number of white blood cells, the morphological changes of the peripheral lymphocytes and some immunological variables were examined in 118 centenarians and in 499 healthy subjects of 60-89 years of age. There was no change in the absolute number of leucocytes, lymphocytes, or T or B cells with age. The occurrence of a myelin-like structure in the mitochondria and the presence of lipofuscin in the cytoplasm of lymphocytes increased with age and showed a correlation with the absolute number of T cells. A correlation could be observed between the absolute number of B cells, serum IgG level and the presence of antinuclear factor.

A small colony of C3H/He and LAF1 mice was set up with 50% of all stock being given a dietary supplement of 0.25% w/w vitamin E to study the range of ageing variables over which anti-oxidant administration has an effect. An increase in mean but not maximum lifespan with vitamin E was attributable to fewer fatalities early in life. This may have been due to low anti-oxidant levels in the controls. Lower fatal tumour incidence in both strains and a decrease in collagen content of LAF mice were noted. Lipofuscin levels in heart tissue were, as expected, reduced but the significance of lipid peroxidation to ageing of the organism is questioned.

In a 13-year-old neurologically healthy boy from a family with adult-onset of metachromatic leukodystrophy (MLD) showing arylsulfatase A-deficiency in the adult, sural nerve biopsy probably was performed 2-3 decades before clinical manifestation of the disease could be expected. Ultrastructurally 4 basic types of inclusion bodies in Schwann cells could be demonstrated (pleo-morphic "zebra body"-like inclusions, double-lamellated inclusions, "tuff-stone"-like inclusions, granular osmiophilic inclusions). Additionally, endoplasmatic reticulum, mitochondria and lysosomes showed marked alterations. Advanced damage of myelin was only rarely seen, but initial segmental demyelination was a common finding. These early pathological changes in chronic MLD are thought to represent a subcellular metabolic insufficiency of Schwann cells in this disease.

Acid fast staining of the bleached residuum of substantia nigra neuromelanin and of oxidized inferior olive lipofuscin was demonstrated in paraffin and frozen sections stained with the acetic acid, carbol fuchsin method of Barbeito-Lopez and the aldehyde fuchsin method of Gomori. Acid fast staining occurred when sections were exposed to a prestain oxidation with potassium permanganate in conjunction with a poststain differentiation with dilute hydrochloric acid. The acid fast staining with acetic acid, carbol fuchsin was differentiable and in contrast to the acid fast staining with aldehyde fuchsin which was nondifferentiable. A possible histochemical basis for differentiable and nondifferentiable acid fast staining was discussed. The identify of the bleached residuum of neuromelanin as lipofuscin was also discussed.

A large tumor of the left lateral ventricle in a 3 1/2 year old male was diagnostic of malignant choroid plexus papilloma (choroid plexus carcinoma) as observed histologically. Focal neoplastic epithelial cells contained yellow-brown pigment which was not entirely compatible with melanin by histochemical techniques. Ultrastructurally, the tumor had definite evidence of choroid plexus origin. The neoplastic cells contained electron-dense and lamellar bodies, as well as structures of intermediate type. Premelanosomes were not observed. Thus there was no evidence for neural crest melanin. It is suggested that the pigment is probably lipofuscin and melanin derived from lipofuscin by "melanization" through pseudoperoxidation.

Common incidental pathologic findings in Old World monkeys are spheroid-like structures and iron pigment in the substantia nigra and globus pallidus. The occurrence of each finding correlates with the number of years monkeys have spent in captivity. The spheroids are eosinophilic and argyrophilic, but are generally PAS, iron, and luxol fast blue negative. Ultrastructurally, they consist of aggregations of dense globules and granules interspersed with membranes; normal organelles are absent. One classic spheroid with a thin myelin sheath and accumulated fibrillar material was observed. The material in spheroids is ultrastructurally distinguishable from iron pigment, which is present in glial cells, and from neuronal lipofuscin. Accumulation of spheroids and iron pigmentation may be age-related phenomena involving portions of the brain with shared anatomical and biochemical characteristics. The study of these changes may shed light on the pathogenesis of such spheroid degenerations as Hallervorden-Spatz disease.

A skin biopsy from a 6-year-old girl was examined by electron microscopy and the diagnosis of ceroid-lipofuscinosis (CL) was confirmed. This has not been reported in the dermatology literature, because of the absence of specific skin manifestations. However, as we have shown, various cells of skin, including fibroblasts, Schwann cells, eccrine serous cells, endothelial cells and smooth muscle cells, accumulated characteristic substances to produce the finger print pattern (FPP) or the curvilinear profile (CLP) which are thought to be diagnostic for CL. Cutaneous ultrastructural research in such cases is important as asymptomatic skin disorders may exist in other congenital storage diseases.

An unusual case of ganglioneuroblastoma containing melanin is presented. Electron microscopy revealed various stages of development of melanosomes in neoplastic cells of Schwann, the first direct demonstration in human material that these cells are malanogenic. The frequent occurrence of neuromelanin in autonomic ganglia and in ganglioneuromas is interpreted as the presence of altered lipofuscin. Review of ultrastructural and other observations indicates a relation between various pigmented tumors, the cell of Schwann, and other cells arising from the neural crest.