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More than 50 hereditary lysosomal storage disorders (LSDs) are currently described. Most of these disorders are due to a deficiency of certain hydrolases/glycosidases and subsequent accumulation of nonhydrolyzable carbohydrate-containing compounds in lysosomes. Such accumulation causing hypertrophy of the lysosomal compartment is a characteristic feature of affected cells in LSDs. The investigation of biochemical and cellular parameters is of particular interest for understanding 'life' of lysosomes in the normal state and in LSDs. This review highlights the wide spectrum of biochemical and morphological changes during developing LSDs that are extremely critical for many metabolic processes inside the various cells and tissues of affected persons. The data presented will help establish new complex strategies for metabolic correction of LSDs. [ABSTRACT FROM AUTHOR]

Transplantable tumors and cell lines have been developed from pheochromocytomas arising in mice with a heterozygous knockout mutation of the neurofibromatosis gene, Nf1. Nf1 encodes a ras-GTPase-activating protein, neurofibromin, and mouse pheochromocytoma (MPC) cells in primary cultures typically show extensive spontaneous neuronal differentiation that may result from the loss of the remaining wild-type allele and defective regulation of ras signaling. However, all MPC cell lines express neurofibromin, suggesting that preservation of the wild-type allele may be required to permit the propagation of MPC cells in vitro. MPC lines differ from PC12 cells in that they express both endogenous phenylethanolamine N-methyltransferase (PNMT) and full-length PNMT reporter constructs. PNMT expression is increased by dexamethasone and by cell-cell contact in suspension cultures. Mouse pheochromocytomas are a new tool for studying genes and signaling pathways that regulate cell growth and differentiation in adrenal medullary neoplasms and are a unique model for studying the regulation of PNMT expression. [ABSTRACT FROM AUTHOR]

Lysosomal storage diseases such as GM1-gangliosidosis are associated with skeletal abnormalities. Radiological and histological studies, both in human and corresponding animal models, indicate retarded bone formation. Since cartilage maturation leads to bone formation, we developed an in vitro system to study and compare the biological features of cartilage from dogs affected with GM1-gangliosidosis with age-matched controls. Costochondral chondrocytes were grown in monolayer and in agarose culture. Both affected and control cells dedifferentiated in monolayer; however, in agarose culture they re-expressed the chondrocytic phenotype. Cells from affected dogs were enlarged and contained numerous large vacuoles when compared with control cells. This morphology was similar to that seen in vivo. In addition, the affected cells appeared to have a reduction in mitosis and alcian blue staining proteoglycans. Cultures from affected animals contained fewer cells positive for alkaline phosphatase activity. Both affected and control cells expressed collagen types I and II and were positive for the lectin Ricinus communis agglutinin-I. However, the staining of the control culture for type II collagen was more prominent than in the affected cells. These findings suggest that culture of chondrocytes in agarose may be a useful method for studying the biology of cartilage which leads to skeletal abnormalities in lysosomal storage diseases. [ABSTRACT FROM AUTHOR]

The development of skeletal lesions in two canine models of GM1-gangliosidosis, English springer spaniels and Portuguese water dogs, has been studied and compared to osseous abnormalities in a child with the infantile form of the disease. In the canine models, skeletal dysplasia was progressive. Lesions were noted at 2 months of age and characterized by retarded endochondral ossification and osteoporosis. Older puppies had focal cartilage necrosis within lumbar vertebral epiphyses. At the cellular level, lesions were characterized by chondrocytic hypertrohy and lysosomal accumulation of storage compounds. Our studies illustrate that the skeletal lesions in both canine models are similar to those in a child with GM1-gangliosidosis. Furthermore, we proposed that the abnormal storage of partially degraded compounds in affected chondrocytes might explain, at least in part, the retarded bone formation noted in patients with GM1-gangliosidosis. [ABSTRACT FROM AUTHOR]

Sections of biopsies of normal skin obtained from 11 individuals were incubated with 8 lectins using an avidin-biotin complex (ABC). All sections when incubated with the appropriate lectin showed the presence of the following carbohydrate residues: l-fucose, β-(1-4)- d-GlcNAc) ( N-acetylglucosamine), acetylneuraminic acid, Gal-β-(1-3)-GalNAc ( N-acetyl-galactosamine), β- d-galactose, α- d-glucose, and α- d-mannose. In addition, sections of individuals with blood group A showed α- d-GalNAc and sections of individuals with blood group B showed α- d-galactose. In the stratum (str.) basale, carbohydrates were present in small quantities, but as the cells matured and moved upward, the incorporation of carbohydrates into the cell membranes increased considerably. In the str. granulosum, lectin reactivity was absent in many sections, probably due to masking by phospholipids. The dark cells in the eccrine glands showed reactivity with all lectins except in the one nonsecretor with blood group A, whose dark cells showed no l-fucose and α- d-GalNAc. The endothelial cells of the blood vessels showed lectin reactivity except when incubated with concanavalin A. The sebaceous glands showed both cytoplasmic and membrane staining when incubated with various lectins. [ABSTRACT FROM AUTHOR]

The clinical, neurophysiological, morphological and biochemical manifestations of eyes from Persian kittens affected with α-mannosidosis were studied. Clinically the disease is characterized by progressive corneal and lenticular opacification. In addition there is asymmetry in shape and latency of signal conductions which were demonstrated by visual evoked potential studies. Morphological and histochemical studies revealed vacuolization of various ocular cell types which stained positively with Concanavalia ensiformis agglutinin (Con A) and wheat germ agglutinin (WGA). Biochemical studies illustrated low activity of acid α-mannosidase in cultured keratocytes and abnormal storage of partially degraded oligosaccharides in these cells, in vitreous humor and lens. This comprehensive study of ocular α - mannosidosis demonstrates enzyme deficiency which leads to abnormal storage of oligosaccharides in affected cells and is manifested by morphological alterations and functional impairment. [ABSTRACT FROM AUTHOR]

A strain of Balb/c mice with neurovisceral storage disorder exhibits metabolic and phenotypic manifestations similar to those found in Niemann-Pick type C and D patients. The storage material in the brain reacted positively with periodate-Schiff reagent. To identify the chemical nature of the storage material we applied lectin histochemistry on paraffin-embedded and frozen sections, using biotinylated lectins and avidin-biotin-peroxidase complex. Major abnormalities were noted in the neurons and glia cells. Swollen neurons were stained heavily by Con A and S-WGA, whereas glia cells, mainly astrocytes, which were abundant both in the cerebrum and cerebellum, were positive to RCA-I, GS-I, PNA, S-WGA and WGA. The myelin tracts reacted with PNA, SBA and RCA-I but to a lesser extent in affected animals when compared to normals. Frozen brain sections stained positively only after extraction with chloroform methanol prior to the lectin treatment and revealed a lectin binding pattern similar to that of the paraffin-embedded preparations. The data presented here show that the stored glucoconjugates in the neurons are of a different chemical composition than those found in glia cells. Since only paraffin embedded sections or lipid extracted frozen sections reacted with the lectins, we suggest that the stored glucoconjugates are glycoproteins or oligosaccharides rather than glycolipids. [ABSTRACT FROM AUTHOR]

Lectin histochemical study was performed on twenty-eight specimens of formalin-fixed paraffin embedded tissues of proximal duodenum from human, cat, dog and Rhesus (macaque) monkey to demonstrate the pattern of carbohydrate residues in submucosal glands of Brunner as compared to that of the duodenal absorptive and goblet cells. Ten different biotinylated lectins were used as probes, and avidin-biotin-peroxidase (ABC) or avidin-gold-silver (AGS) complexes were used as 'visualants'. Brunner's gland cells of the four species studied exhibited a similar lectin-binding pattern which differ from other duodenal cells. The epithelium of Brunner's gland stained intensely with Ricinus communis agglutinin-I (RCA-I), succinylated-WGA (S-WGA) and wheat-germ agglutinin (WGA), moderately with Bandeirea simplicifolia agglutinin-I (BS-I), Concanavalia ensiformis agglutinin (Con A) peanut agglutinin (PNA) and Ulex europaeus agglutinin-I (UEA-I) and occasionally with Dolichos biflorus agglutinin (DBA), Lens culinaris agglutinin (LCA) and soybean agglutinin (SBA). Desialylation with neuraminidase resulted in only a slight elevation in binding intensities of PNA, DBA and SBA, indicating that glycoconjugates of the Brunner's gland cells are rich in asialo-oligosaccharides, which differs from duodenal epithelial cells. In addition, these histochemical reagents were useful in localizing Brunner's gland elements in the duodenal mucosa. [ABSTRACT FROM AUTHOR]

Lectin-histochemical studies were performed on formalin-fixed, paraffin-embedded tissues from ten mammalian species to demonstrate the pattern of carbohydrate residues in vascular endothelium. Ten different biotinylated lectins were used as probes and avidin-biotin-peroxidase complex (ABC) was used as visualant. Ricinus communis agglutinin-I (RCA-I) and wheat germ agglutinin (WGA) stained vascular endothelium in all species. Peanut agglutinin (PNA) stained vascular endothelium in all species only after preincubation with neuraminidase. Bandeirea simplicifolia agglutinin-I (BS-I) stained vascular endothelium in all species but human, while, Ulex europeus agglutinin-I (UEA-I) stained only human endothelium. Individual differences in staining of human vascular endothelium were noted with BS-I and succinylated-WGA (SWGA). Similarly, individual differences in staining of animal vascular endothelium were noted with soybean agglutinin (SBA) after preincubation with neuraminidase. Finally, Concanavalia ensiformis agglutinin (Con A), Dolichos biflorus agglutinin (DBA) and Lens culinaris agglutinin (LCA) did not stain vascular endothehuman in any of the species studied. [ABSTRACT FROM AUTHOR]

In the present study, we have investigated the use of avidin-gold complex (AG) as a possible cytochemical marker for visualizing and identifying lectin receptors in deparaffinized tissue sections. Monodispersed gold sols of 15 nm average diameter were prepared by sodium citrate reduction. The AG complex was prepared with highly purified egg-white avidin (avidin-D). Deparaffinized sections of cat duodenum were labeled with five different biotinylated lectins, then were washed and stained for 1-2 h with AG. Intensification of the gold staining was achieved by a modification of the silver-enhancement method. For each lectin, the labeling properties of the avidin-gold-silver (AGS) were compared with those of the avidin-biotin-peroxidase (ABC) and the lectin-gold (LG) methods. We found the lectin binding pattern demonstrated by the AG method to be similar to that of the ABC. The AG localization of the carbohydrate residues is more precise, compared to the peroxidase reaction due to lack of diffusion of the gold marker. Labeling with AGS resulted in improved staining over the AG method, similar to the staining intensity of the ABC. In addition, the two-step AG method provided more intense staining than the direct one-step procedure of the lectin-gold labeling. In conclusion, the use of the AGS method for histochemical visualization of lectin receptors requires a simple two-step procedure which allows highly accurate localization of tissue glycoconjugates. It entails using only a single gold-ligand complex applicable to any biotinylated lectin regardless of its biochemical nature. It can also be easily adapted for use with other biotinylated ligands such as antibodies, hormones, toxins, etc. [ABSTRACT FROM AUTHOR]

Expiants obtained from the media of swine abdominal aortas, free of intimai cells and of vasa vasis, were cultivated in a semisynthetic medium for various periods of time, up to 50 days. Under these conditions it was observed that some smooth muscle cells, apparently independently from their location, undergo dedifferentiation, become rich in organelles, migrate and possibly multiply. These cells, found outside the original expiant, are capable of synthesis of collagen and elastic substance. Other cells seem unable to become activated and after some time die. It is suggested that cells capable of dedifferentiation 'in vitro' may be the same that 'in vivo' under adequate stimulation are responsible for proliferative atherosclerotic lesions. [ABSTRACT FROM AUTHOR]

Asymmetric unit membrane (AUM) is a component of the luminal membrane of urinary bladder in many species. In normal human adults it is inconspicuous, but it becomes prominent following incidental exposure to therapeutic irradiation. [ABSTRACT FROM AUTHOR]

Synthesizing trait observations and knowledge across the Tree of Life remains a grand challenge for biodiversity science. Species traits are widely used in ecological and evolutionary science, and new data and methods have proliferated rapidly. Yet accessing and integrating disparate data sources remains a considerable challenge, slowing progress toward a global synthesis to integrate trait data across organisms. Trait science needs a vision for achieving global integration across all organisms. Here, we outline how the adoption of key Open Science principles-open data, open source and open methods-is transforming trait science, increasing transparency, democratizing access and accelerating global synthesis. To enhance widespread adoption of these principles, we introduce the Open Traits Network (OTN), a global, decentralized community welcoming all researchers and institutions pursuing the collaborative goal of standardizing and integrating trait data across organisms. We demonstrate how adherence to Open Science principles is key to the OTN community and outline five activities that can accelerate the synthesis of trait data across the Tree of Life, thereby facilitating rapid advances to address scientific inquiries and environmental issues. Lessons learned along the path to a global synthesis of trait data will provide a framework for addressing similarly complex data science and informatics challenges.

The fossil record provides one of the strongest tests of the hypothesis that diversity within local communities is constrained over geological timescales. Constraints to diversity are particularly controversial in modern terrestrial ecosystems, yet long-term patterns are poorly understood. Here we document patterns of local richness in Phanerozoic terrestrial tetrapods using a global data set comprising 145,332 taxon occurrences from 27,531 collections. We show that the local richness of non-flying terrestrial tetrapods has risen asymptotically since their initial colonization of land, increasing at most threefold over the last 300 million years. Statistical comparisons support phase-shift models, with most increases in local richness occurring: (1) during the colonization of land by vertebrates, concluding by the late Carboniferous; and (2) across the Cretaceous/Paleogene boundary. Individual groups, such as mammals, lepidosaurs and dinosaurs also experienced early increases followed by periods of stasis often lasting tens of millions of years. Mammal local richness abruptly tripled across the Cretaceous/Paleogene boundary, but did not increase over the next 66 million years. These patterns are consistent with the hypothesis that diversity is constrained at the local-community scale.