The distribution of proteoglycans of high electrophoretic mobility in cartilages from different species and of different ages

The distribution of small proteoglycans of high relative electrophoretic mobility in cartilage of various species and of different ages was studied. Proteoglycans extracted by 4 M guanidinium chloride were purified by ion-exchange chromatography and assessed by gel electrophoresis. Proteoglycans fractionated by equilibrium density gradient centrifugation under ‘dissociative’ conditions were similarly purified and assessed. A rapid migrating population was found in articular cartilages of young humans, baboons, calfs, pigs, rabbits, rats, chickens and in mandibular and vertebral cartilages of dog-fish. It was not detected in unfractionated proteoglycans extracted from fetal rat, pig, calf, baboon and human cartilages. In baboon and human fetal cartilages of advanced gestational age, however, small amounts of the rapid population were present being detected in the low density fractions of dissociative gradients. The rapid migrating population was not found either in unfractionated or in fractionated proteoglycans obtained from articular cartilages of humans aged over 40. It was absent from human osteoarthritic cartilages but was detected even at advanced age in cartilages covering osteophytes.     

Gene and protein expressions of type I collagen are regulated tissue-specifically in rat hyaline cartilages in vivo

The present study was designed to investigate how rat hyaline cartilages at various sites in vivo express the gene and protein of type I collagen using in situ hybridization and immunohistochemistry. The gene of pro alpha 1(I) collagen was expressed by chondrocytes in articular cartilage, and the protein of type I collagen was identified in the cartilage matrix. In contrast, growth plate cartilage expressed the gene of pro alpha 1(I) collagen, but no protein of type I collagen. Neither gene nor protein of type I collagen was expressed in cartilages of trachea and nasal septum. The present study suggested that expression of type I collagen in hyaline cartilages may be regulated tissue-specifically at gene and/or protein levels.     

The structure, location, and function of perlecan, a prominent pericellular proteoglycan of fetal, postnatal, and mature hyaline cartilages

The aim of this study was to immunolocalize perlecan in human fetal, postnatal, and mature hyaline cartilages and to determine information on the structure and function of chondrocyte perlecan. Perlecan is a prominent component of human fetal (12-14 week) finger, toe, knee, and elbow cartilages; it was localized diffusely in the interterritorial extracellular matrix, densely in the pericellular matrix around chondrocytes, and to small blood vessels in the joint capsules and perichondrium. Aggrecan had a more intense distribution in the marginal regions of the joint rudiments and in para-articular structures. Perlecan also had a strong pericellular localization pattern in postnatal (2-7 month) and mature (55-64 year) femoral cartilages, whereas aggrecan had a prominent extracellular matrix distribution in these tissues. Western blotting identified multiple perlecan core protein species in extracts of the postnatal and mature cartilages, some of which were substituted with heparan sulfate and/or chondroitin sulfate and some were devoid of glycosaminoglycan substitution. Some perlecan core proteins were smaller than intact perlecan, suggesting that proteolytic processing or alternative splicing had occurred. Surface plasmon resonance and quartz crystal microbalance with dissipation experiments demonstrated that chondrocyte perlecan bound fibroblast growth factor (FGF)-1 and -9 less efficiently than endothelial cell perlecan. The latter perlecan supported the proliferation of Baf-32 cells transfected with FGFR3c equally well with FGF-1 and -9, whereas chondrocyte perlecan only supported Baf-32 cell proliferation with FGF-9. The function of perlecan therefore may not be universal but may vary with its cellular origin and presumably its structure.     

The distribution of chondroitin sulfates in articular and growth cartilages of human bones.

The relative contents of chondroitin 4- and 6-sulfates in cartilages of different human bones are reported. Articular and vertebral body cartilages contain almost exclusively chondroitin 6-sulfate, whereas growth and subarticular cartilages contain nearly equal amounts of chondroitin 4-sulfate and chondroitin 6-sulfate. Adult cartilages, where the calcification process is complete, contain only chondroitin 6-sulfate. These results that chondroitin 4-sulfate may be an important component for the calcification process, whereas chondroitin 6-sulfate seems to be related to the integrity of the articular surfaces. A chemical defect of chondroitin 6-sulfate in a new mucopolysaccharidosis, characterized by platyspondyly and irregularities of articular surfaces, is in agreement with these results.     

Chondroitin sulfates of the epiphysial cartilages of different mammals.

1. The distribution chondroitin 4- and 6-sulfates in the epiphysial cartilages of several mammals are reported. 2. Chondroitin 6-sulfate is present in higher relative proportion in articular surfaces of young and adult epiphysial cartilages in most of the mammals studied. 3. Exception to this was found in some species of the order Rodentia in which chondroitin 4-sulfate was almost the only chondroitin present in young and adult cartilages. 4. These and other results suggest that chondroitin 4-sulfate may be an important component for the calcification process, whereas chondroitin 6-sulfate seems to be related to the integrity of the articular surfaces.     

The distribution of glucosamine in mammalian glycogen from different species, organs and tissues

The reasons for the occurrence of trace amounts of glucosamine in animal liver glycogens have been explored. Human liver glycogen is now shown to contain this amino sugar. Galactosamine, known to be the source of the incorporated glucosamine, is found to give rise to glucosamine in glycogen when administered orally, or as the N-acetyl derivative. The rabbit can also incorporate glucosamine into kidney glycogen but not into glycogen in heart or skeletal muscle. These experiments led to the discovery that glucosamine is incorporated into rabbit liver glycogen in such a way that there is intermolecular heterogeneity in the content of glucosamine, suggesting that there exists more than one pool of liver glycogen.     

The molecular taxonomy and evolution of the guinea pig.

On the basis of 18 protein sequences totaling 2,413 aligned amino acid sites, it is suggested that the guinea pigs and the myomorphs (rat-like rodents) are not monophyletic. Rather, the evolutionary lineage leading to the guinea pig seems to have branched off prior to the divergence among myomorphs, lagomorphs, primates, chiropterans, artiodactyls, and carnivores. It is suggested therefore that the Caviomorpha (guinea pig-like rodents) and possibly the Hystricomorpha (porcupine-like rodents) should be elevated in taxonomic rank and conferred an ordinal status distinct from the Rodentia. This suggestion calls for a reevaluation of the morphological evolution of guinea pigs and further molecular studies on the possibility of paraphyly of the order Rodentia. If the monophyly of rodents holds, it must be concluded that the pattern of molecular evolution in many guinea pig genes has been extremely unusual and that the causes for this pattern should be sought. It is also suggested that claims of large differences in the rate of molecular evolution between guinea pigs and myomorphs may have been exaggerated in many cases as a result of an erroneous phylogenetic position for the guinea pig. The average rate of amino acid replacement in the guinea pig seems to be comparable to that in the rat and the mouse. However, the data indicate that myomorph and caviomorph genes evolve, on average, about two times faster than their human counterparts. Finally, our analysis provides evidence against the hypothesis that the gundi (an African rodent) represents the most ancient rodent lineage.     

Helicobacter species colonizing pig stomach: molecular characterization and determination of prevalence.

The infection rate of 60 pigs (10 pigs from each of six farms) by Helicobacter species was studied by two techniques. Histological examination of the cardiac area of the stomach yielded a 58% positive result versus an 80% positive result by PCR with genus-specific primers. Eighty percent of the 16S rRNA gene was amplified, classified in four groups by PCR-restriction fragment length polymorphism, and sequenced. Isolates from all farms except one (farm C) were identified as Helicobacter heilmannii type 1, while those from farm C were identified as H. heilmannii type 2. Attempts to culture this organism in vitro failed. Helicobacter pylori was not found in these animals.     

The distribution patterns of COMP and matrilin-3 in septal,alar and triangular cartilages of the human nose

The biomechanical characteristics of septal cartilage depend strongly on the distinct extracellular matrix of cartilage tissue; therefore, it is essential that the components of this matrix are identified and understood. Cartilage oligomeric matrix protein (COMP) and matrilin-3 are localised in articular cartilage. This study was the first to examine all subtypes of mature human nasal cartilages (alar, triangular and septal) with specific attention to the distribution of COMP and matrilin-3. Three whole fresh-frozen noses from human donors were dissected, and exemplary biopsies were examined using histochemical staining (haematoxylin and eosin and Alcian blue) and immunohistochemistry (collagen II, COMP and matrilin-3). The following three zones within the nasal cartilage were identified: superficial, intermediate and central. COMP was detected as highest in the intermediate zones in all three subtypes of nasal cartilage, whereas matrilin-3 was detected with pericellular deposition mainly within septal cartilage predominantly in the superficial zones. The distinct staining patterns of COMP and matrilin-3 underscore the different functional roles of both proteins in nasal cartilage. According to the literature, COMP might be involved with collagen II in the formation of networks, whereas matrilin-3 is reported to prevent ossification or regulate mechanosensitivity. The predominant staining observed in septal cartilage suggests matrilin-3’s modulatory role because of its presence in the osteochondral junctional zone and given that the biomechanical load in septal cartilage is different from that in alar or triangular cartilage. In conclusion, COMP and matrilin-3 were detected in mature human nasal cartilage but displayed different staining patterns that might be explained by the functional roles of the respective matrix protein; however, further research is necessary to identify and define the functional aspects of this morphological difference.     

The distribution of galanin message-associated peptide-like immunoreactivity in the pig.

Using a radioimmunoassay (RIA) developed to the N-terminal part of the predicted sequence of porcine galanin message-associated peptide (GMAP), we have confirmed the existence of GMAP-like immunoreactivity (-LI) in normal porcine tissues. GMAP-LI was found to parallel the distribution of galanin-immunoreactivity (-IR), although consistently the concentrations detected were, on a molar ratio, significantly less than those measured for galanin throughout the gastrointestinal tract, brain, spinal cord, adrenal and pituitary gland. As cleavage of the prohormone would be expected to produce galanin and GMAP on an equimolar basis, it is possible that the endogenous, intact GMAP peptide does not fully cross-react with the antibody raised to the N-terminal GMAP sequence. Gel chromatography of tissue extracts revealed a single molecular form of galanin-IR in the gut and four distinct molecular forms in the adrenal gland. GMAP-LI eluted as a single immunoreactive component in the gut, and in the adrenal gland there were two major molecular forms, one of which was apparently also detected by the galanin assay, and a small amount of N-terminal fragment. This molecular heterogeneity seems likely to be a result of the various possible prohormone cleavage products and/or posttranslational processing modifications. Further analysis of the galanin gene products needs to be undertaken in order to confirm this.     

Quantitative analysis of chondrocyte distribution patterns in hyaline cartilage tissue--a comparison of different models

The purpose of our investigations were aging changes in hyaline cartilage of the trachea and of the larynx. 42 samples of carina tracheae and 29 samples of arytenoid cartilage were used in both organs from the newborn age up to the age of 91 a. We have examined patterns of cell distribution with the help of the computer programme "Dichte" ("density") using the following methods of stochastic geometry: product density, L function, and others. Product density allows for a reliable destination between a regular pattern of cells (hard-core distribution), a random pattern (soft-core distribution), and a typical clustering of chondrocytes. 2 examples of arytenoid cartilage have been selected to demonstrate the possibilities of interpretation of product density supported by the L function. Soft-core and in few cases hard-core distribution have been found both with the carina tracheae and the cartilago arytaenoidea in the 1st decade of life. Beginning with the 2nd decade of life, the typical clustering of chondrocytes have been confirmed with both organs.     

Reconstituted collagen fibrils. Fibrillar and molecular stability of the collagen upon maturation in vitro.

During the maturation in vitro of reconstituted collagen fibrils prepared from rat skin, the mechanical and thermal stability of collagen increased and the pepsin-solubility decreased. At the same time a larger fraction of the pepsin-soluble collagen attained a lower molecular thermal stability that resulted in a biphasic thermal transition of the soluble collagen. Type-I collagen, with a similar biphasic thermal transition, was isolated from acid-insoluble rat skin collagen.     

Uptake and distribution of selenium in different fern species

There has been an interest in using hyperaccumulating plants for the removal of heavy metals and metalloids. High selenium (Se) concentrations in the environment are detrimental to animals, humans, and sustainable agriculture, yet selenium is also an essential nutrient for humans. This experiment was conducted to screen fern plants for their potential to accumulate selenium. Eleven fern species, Pteris vittata, P. quadriaurita, P. dentata, P. ensiformis, P. cretica, Dryopteris erythrosora, Didymochlaena truncatula, Adiantum hispidulum, Actiniopteris radiata, Davallia griffithiana, and Cyrtomium fulcatum, were grown under hydroponic conditions for one week at 20 mg L(-1) selenate or selenite. Root Se concentrations reached 245-731 and 516-1082 mg kg(-1) when treated with selenate and selenite, respectively. The corresponding numbers in the fronds were 153-745 and 74-1,028 mg kg(-1) with no visible toxicity symptoms. Only three fern species were able to accumulate more Se in the fronds than the roots, which were D. griffithiana when treated with selenate, P. vittata when treated with selenite, and A. radiata regardless of the forms of Se. A. radiata was the best species overall for Se accumulation. More research is needed to further determine the potential of the fern species identified in this study for phytoremediation of the Se contaminated soils and water.     

Lectin histochemistry of the hyaline layer around the larvae of Patiriella species (Asteroidea) with different developmental modes.

Larvae of sea stars are surrounded by an extracellular matrix called the hyaline layer. The lectin-binding properties of this matrix were investigated in an ultrastructural study of Patiriella species having different modes of development. The planktonic bipinnaria and brachiolaria of P. regularis and the planktonic brachiolaria of P. calcar demonstrated the same labeling of the hyaline layer for three lectins: Con A, SBA, and WGA. In both species the outer coarse meshwork stained for all three lectins, whereas the intervillous layer displayed patchy labeling. In the benthic brachiolaria of P. exigua, the outer coarse meshwork displayed heavy labeling for all three lectins. The heavy labeling of the outer coarse meshwork of P. exigua compared with that of the other species suggests an increased number of lectin binding sites in the hyaline layer of this species. The similar ultrastructure and histochemistry of the hyaline layer of P. regularis and P. calcar may reflect similar requirements of their extracellular cover in their planktonic environment. Lectin labeling shows that hypertrophy of the hyaline layer of P. exigua, in particular the outer coarse meshwork, involves elaboration of the carbohydrate composition of the matrix. Modifications seen in the ultrastructure and histochemistry of the hyaline layer of P. exigua appear to be associated with the evolution of benthic development.     

不同区域典型树木的空间分布格局及关联性

以温带长白山(CBS)、暖温带关帝山(GDS)、亚热带黑石顶(HSD)样地监测数据为基础,采用成对相关函数g(r)分析了3个样地共有的3科(松科、壳斗科、蔷薇科)树木的空间分布格局及其关联性.结果表明:不同样地3科树木分布数量及结构特征存在差异.松科在GDS分布数量较多,呈双峰型径级结构,在CBS和HSD分布数量少,径级结构近似正态分布;壳斗科在CBS和GDS分布数量少,分别呈双峰型和偏正态径级结构,在HSD分布数量多,呈倒"J"型径级分布;蔷薇科在GDS分布数量多,呈"L"型径级分布,在CBS和HSD分布相对较少,径级结构分别呈倒"J"型和"L"型分布.3科树木空间分布格局在不同样地表现也不同,松科的大径级个体在CBS和GDS小尺度上呈均匀分布,在HSD呈聚集分布,中、小径级在3个样地均呈聚集分布;壳斗科在CBS以大径级个体为主,呈近似随机分布,在GDS和HSD以中、小径级为主,呈聚集性分布格局;蔷薇科在3个样地均为聚集分布.3科树木的聚集程度均随尺度增加而降低.大径级的壳斗科个体在CBS和HSD与松科呈不相关或小尺度负相关关系,中、小径级的壳斗科在CBS和GDS与松科呈负相关关系,但在HSD与松科表现为正相关;松科与蔷薇科在3个样地均表现为负相关;中、小径级的壳斗科与蔷薇科在CBS和GDS呈正相关关系,但在HSD呈负相关关系.总之,3科树木空间分布格局及关联性随径级、尺度而变化且在不同样地内有不同表现.     

Preservation of elastic system fibers and of collagen molecular arrangement and stainability in an Egyptian mummy

The present findings show that both elastic system fibers and collagen markedly resisted change in tissues more than 2000 years old. The distribution of elastic fibers and elastic-related fibers (namely, oxytalan and elaunin fibers) in mummified tissues coincided with the observations made on the modern human tissues used as controls. The collagenous structures present in tissue sections obtained from the Egyptian mummy studied took on a deeply red colour when stained in the Picrosirius solution indicating that, as well as in the fresh controls, the basic groups in the collagen molecules were available for reacting with the strongly acidic dye Sirius Red. When viewed with polarized light, the collagen in the same tissue sections displayed an increased birefringence, which shows that the collagen molecules in mummified tissues maintain the oriented disposition which is typical of the modern human tissues used as controls. The methods employed have proved to be useful for the delineation of the elastic system fibers and of the collagenous scaffolding, which may be used as valuable landmarks in the study of the histoarchitecture of organs that have undergone considerable distortion.