Connective-tissue macromolecules in Golgi chicken tendon organs and at their interface with muscle fibers and adjoining tendinous structures

Tendon organs from leg and forearm muscles of white leghorn chickens were examined with a library of monoclonal antibodies to determine the composition of their connective-tissue framework and the types of connective-tissue macromolecules that occur at the sites where muscle fibers attach to the receptors. The capsules of the tendon organs were positive for connective-tissue macromolecules typical of basal lamina (collagen type IV, laminin, and heparin sulfate proteoglycan) and for tenascin, collagen types III and VI, and fibronectin. Connective-tissue bundles in the lumen of a receptor reacted primarily with antibodies against collagen type I and 4-chondroitin sulfate. The narrow partitions that divide each lumen into compartments stained for collagen type III. Toward its tendinous end, a receptor made few contacts with muscle fibers. Instead, the capsule and the collagenous bundles blended gradually with the intermuscular portions of tendons. At the muscular end, the connections were more complex. Muscle fibers that attached in series to tendon organs split to produce basal lamina-covered, finger-like extensions, which were separated from each other by fissures. Tongues of connective tissue containing tenascin, collagen types I and VI, and fibronectin extended into the fissures. Distally the tongues were continuous with the tenascin in the capsule and just internal to the capsule, fibronectin and basal lamina macromolecules in the capsule, and collagen type I in the collagenous bundles. The uninterrupted presence of these macromolecules around terminating muscle fibers and in the capsule and/or the intraluminal collagen bundles suggests that muscle fibers that attach in series at the muscular end exert a force during muscular contraction on the intraluminal collagen bundles and on the receptor capsule.

In vivo biocompatibility of collagen-poly(hydroxyethyl methacrylate) hydrogels

Collagen-p(HEMA) hydrogels were subcutaneously implanted in rats for up to 6 month and the immediate short- and long-term tissue response to these implants was studied. Histopathological data indicated that the tissue reaction at the implant site progressed from an initial acute inflammatory response characterized by the presence of eosinophils and polymorphs to a chronic response marked by few macrophages, foreign body giant cells and fibroblasts. After one month a very thin fibrous capsule (approximately 11 microns thick) was observed around the implant. Even 6 month post-implantation, the capsule thickness was maintained at about 11-12 microns. No necrosis, calcification, tumorigenesis or infection was observed at the implant site up to 6 month. Fibrous capsule analysis showed that the collagen content and the capsule thickness were well within the threshold limits. The collagen-p(HEMA) hydrogels were found to be well-tolerated, non-toxic and highly biocompatible.

Distribution of factor XIIIa-containing cells and collagenous components in radicular cysts: histochemic and immunohistochemic studies

The distribution of subunit A of Factor XIII (FXIIIa) and of collagenous components was investigated by the avidin-biotin-peroxidase complex (ABC) method for FXIIIa and by the Sirius red F3BA method, respectively, in 43 cases of radicular cysts. Besides the covering epithelial layer, the radicular cyst wall was composed of the following three layers: an inner granulomatous layer, an outer fibrous connective tissue layer, and an intermediate layer. In each layer, a positive reaction for FXIIIa was observed in certain connective tissue cells. These FXIIIa-containing cells were few in number in the inner layer where collagenous components were also sparse. In the slightly to moderately fibrous intermediate layer, these cells markedly increased in number and were dendritic or stellate in shape. In the outer densely fibrous connective tissue layer, they decreased slightly in number and were slender and spindle-shaped. The results obtained in the present study indicate the close relationship between the distribution of FXIIIa-containing cells and of collagenous components. Such a relationship suggests that these cells play an important role in the process of fibrosis occurring in the radicular cyst wall.

Hydrogen/fluorine retuning tomography. Applications to 1H image-guided volume-selective 19F spectroscopy and relaxometry of perfluorocarbon emulsions in tissue

A hardware modification which permits the record of 19F images, spectra, and relaxation times with a 1H tomography bird-cager resonator is described. Changing the spectrometer frequency from 1H to 19F resonance and vice versa is possible without removing the object to be investigated. This hydrogen/fluorine retuning tomography (HYFY) technique permits studies of identical slices or volume elements with 1H as well as with 19F resonance. In particular, it is possible to localize volume elements on the basis of multislice proton images and then to investigate these volume elements with fluorine magnetic resonance by the aid of volume selection methods. For this purpose, pulse sequences for the localized and spectroscopically resolved determination of spin-lattice and transverse relaxation times have been developed. The applicability of the techniques has been demonstrated by the aid of phantom samples as well as with excised porcine organs which have been perfused with perfluorocarbon emulsions.

Analysis of ecdysteroids in Onchocerca gibsoni, O. volvulus and nodule tissues

Free ecdysteroids were detected in Onchocerca gibsoni, in tissues constituting O. volvulus and O. gibsoni nodules and in unrelated bovine tissues. Ecdysone and 20-hydroxyecdysone were identified by HPLC-RIA and GC/MS(SIM). The concentration of free ecdysteroids in the nodule tissue immediately surrounding the parasites was at least an order of magnitude higher than that detected in the worms themselves, or in adjacent nodular tissues or other bovine tissues.

Human salivary gland glycoconjugates: a lectin histochemical study

The glycoconjugate content of normal salivary glands has been extensively investigated in humans by biochemical means and in non-human mammals by histochemical methods. However, there have been few histochemical studies of human tissues. This paper describes the findings obtained in parotid, submandibular and minor salivary glands by applying a panel of 13 biotinylated lectins, directed against a range of N-linked, fucosylated and galactosylated sequences, using an avidin-peroxidase technique, with appropriate enzymatic and inhibitory sugar controls. The results were generally in accord with those observed in biochemical assays but the use of lectin histochemistry permitted the localization in situ of small amounts of oligosaccharide and, therefore, allowed the recognition of subtle tissue differences. This study expands the current knowledge on the glycoconjugate composition of salivary glands and their lectin histochemistry and serves as a baseline for further studies, particularly in the field of neoplasia.

Distribution of elastin and collagen in canine lung alveolar parenchyma

We have quantified the fibrous collagen (predominantly type I) and elastin in four locations of perceived mechanical importance: one quasi-planar feature, the alveolar septum or wall (W), and three linear features, the junction (J) of three septa, the free edges (E) of septa, and the line along which two septa join at a distinct angle or bend (B). The frequencies of these four features on light micrographs and the areas of transections through collagen and elastin seen on electron micrographs were combined to give the volumes of collagen and elastin within each feature. We find that E and B have similar compositions and contain most (4/5) of the parenchymal elastin in their relatively heavy cables. The E and B are interconnected and similar in location and composition, and they may constitute a functional entity in which elastin provides tension over a range of lung volumes, opposing septal tensions. In J and W, elastin is typically sparse and fine. Calculations, however, suggest it contributes the dominant portion of septal tension at lower lung volumes. Elastin may be essential to stabilizing septal configuration. Collagen, on the other hand, is distributed relatively evenly throughout E, B, J, and W, consistent with the role of protecting all components against rupture.

Changes in the connective tissue of corpus and cervix uteri during ripening and labour in term pregnancy

The composition of the connective tissue of human cervix and corpus uteri was studied in tissue specimens from seven nonpregnant women and 14 pregnant women, delivered at term by section, to examine spontaneous cervical ripening and labour-induced changes in both the uterine and the cervical connective tissue. The main finding in both the cervix and the corpus was a large (40-60%) decrease of the collagen concentration. The collagen extractability, obtained by pepsin digestion, was increased twofold, suggesting a change of the organization of the collagen fibrils. This reorganization process could also be demonstrated by a large increase of the collagenolytic activity demonstrated with an artificial DNP-peptide substrate. The concentrations of sulphated glycosaminoglycans was lower in pregnant women than in non-pregnant women. The results show that both the cervix and the corpus uteri contain substantial amounts of connective tissue components (collagen, sulphated glycosaminoglycans and hyaluronic acid) and that during ripening, reconstruction of the connective tissue components occurs in both sites. This indicates that the cervical state reflects that of the myometrium.

Changes in the connective tissue of corpus and cervix uteri during ripening and labour in term pregnancy

The composition of the connective tissue of human cervix and corpus uteri was studied in tissue specimens from seven nonpregnant women and 14 pregnant women, delivered at term by section, to examine spontaneous cervical ripening and labour-induced changes in both the uterine and the cervical connective tissue. The main finding in both the cervix and the corpus was a large (40-60%) decrease of the collagen concentration. The collagen extractability, obtained by pepsin digestion, was increased twofold, suggesting a change of the organization of the collagen fibrils. This reorganization process could also be demonstrated by a large increase of the collagenolytic activity demonstrated with an artificial DNP-peptide substrate. The concentrations of sulphated glycosaminoglycans was lower in pregnant women than in non-pregnant women. The results show that both the cervix and the corpus uteri contain substantial amounts of connective tissue components (collagen, sulphated glycosaminoglycans and hyaluronic acid) and that during ripening, reconstruction of the connective tissue components occurs in both sites. This indicates that the cervical state reflects that of the myometrium.

Simultaneous determination of the reducible and nonreducible cross-links of connective tissue. Analysis of mineralized and nonmineralized bone collagen

Secondary amine cross-links occur in collagen and elastin from a number of tissue sources. Quantification of these cross-links by amino acid analysis is complicated by the problem of separating cross-links, which are often minor components, from the more common amino acids and also because relatively large amounts of a cross-link are required to determine a color factor. A specific radioactive labeling method has been developed and used to quantify cross-links in bone collagen. Primary amines such as lysine and hydroxylysine are first guanidinated with 3,5-dimethylpyrazole-1-carboxamidine nitrate (DMPC). Secondary amines, which are unreactive with DMPC, are then quantitatively cyanoethylated with [14C]acrylonitrile. This procedure can be used to detect any secondary amine cross-link, with higher sensitivity than ninhydrin analysis, in peptide form as well as in acid hydrolysates. It is applied here in conjunction with [3H]NaBH4 reduction to simultaneously quantify Schiff base cross-links and amounts of in vivo reduction of Schiff bases in mineralized versus nonmineralized bovine bone.

Immunohistochemical localization of chondroitin sulfate and dermatan sulfate proteoglycan in human gingival connective tissue

This study investigated the immunohistochemical localization of chondroitin sulfate (chondroitin, 4-sulfate and 6-sulfate) and dermatan sulfate proteoglycan (PG) in human gingival connective tissue, using monoclonal antibodies. Dermatan sulfate was found to be widespread in connective tissue, with an especially strong response shown in collagen fiber bundles under the epithelial basement membrane. Chondroitin 4-sulfate occurred widely in connective tissue but showed only a weak response. Chondroitin 6-sulfate was located in peripheral blood vessels. Chondroitin was not detected in gingival connective tissue.

Factor XIIIa-containing cells and fibrosis in oral and maxillofacial lesions: an immunohistochemical study

The distribution of subunit A of blood coagulation factor XIII (FXIIIa) was investigated by the avidin-biotin-peroxidase complex (ABC) method in various oral and maxillofacial tissues. These tissues were from normal tongue, gingiva, lip, and submandibular gland, and from Dilantin gingival hyperplasia (one case), pyogenic granuloma (three cases), peripheral fibroma (four cases), squamous cell carcinoma (seven cases), chronic sclerosing submandibular adenitis (two cases), and fibrous dysplasia of the mandibular bone (one case). The distribution of collagenous components was examined in the same tissues by means of the Sirius red F3BA method. By means of the ABC method, FXIIIa was detected in the cytoplasm of certain connective tissue cells in each of the tissues examined. These FXIIIa-containing cells were sparse in the normal tissues but evidently abundant in the fibrous connective tissue of inflammatory and neoplastic lesions. In the present study, the close relationship between the distribution of FXIIIa-containing cells and that of collagenous components is demonstrated. The role that FXIIIa-containing cells play in the process of fibrosis is discussed.

Induction of connective tissue by various alloplastic materials: an experimental study in rats

The capacity of three alloplastic implant materials to induce connective tissue was tested on the backs of 19 rats. A standardized viscous sponge served as control material. The commercial implant materials studied were carbon fibre and polypropylene ligament prostheses and a sponge composite of polytetrafluorethylene polymer and graphite fibre. Quantitative biochemical analyses (DNA, RNA, hydroxyproline and hexosamines) were done at 3 and 10 d, and 3, 6 and 9 wk post-operatively. Histological studies were done at 3, 6 and 9 wk. During the follow-up all the materials, when implanted subcutaneously, showed some capacity to induce ingrowth of granulation tissue. However, according to both quantitative chemical analyses and histological studies, the inductive capacity was greatest in the control sponge and in the polypropylene ligament prosthesis. In contrast, chemical analyses showed that the amount of granulation tissue developing during the follow-up was least in the rats with carbon fibre ligament implants.

Microprobe analysis of element distribution in bovine extracellular matrices and muscle

The concentrations of some essential elements, Na, K, P, S and Cl were determined by microprobe analysis in bovine extracellular matrices of cartilage, tendon and elastic tissue (ligamentum nuchae) and in muscle cells. The values for the different tissues were compared and related to the blood electrolyte concentrations. Among the connective tissues the highest Na and lowest Cl values were found for cartilage which bears a high negative charge. The lowest concentrations of these elements occurred in elastic tissue which is relatively non-polar. In the three extracellular matrices sodium levels exceeded potassium. In myofibers potassium was the major cation at 30 times the blood value and about 3 times the concentration of sodium. Chlorine values were around 0.4 that of blood. Sulfur and phosphorus are components of the tissue macromolecules. The negative charge on the extracellular matrices is a function of carboxyl and sulfate radicals. In the myofiber this property is largely attributable to carboxyl and phosphate groups. Differences in potassium-sodium distribution in cells and extracellular matrices are attributed partly to the microtrabecular lattice and to the ordered state of cell water. In general the element concentrations and selective distribution can be related to the chemical composition and organization of the tissue, the net immobile charge, the nature of the dispersion medium (water) and changes in its dielectric constant, and to the physico-chemical properties of the individual ions.

Connective tissue-associated proteins in crevicular fluid: potential markers for periodontal diseases

Tests for periodontal disease that are able to detect both ongoing and future loss of clinical attachment would be valuable assets in determining the diagnosis and treatment of periodontal diseases. We hypothesized that connective tissue-associated proteins could be detected in crevicular fluid and would reflect the biochemical activity of the periodontium in health and disease. To test this hypothesis, crevicular fluid samples obtained from patients with various states of periodontal disease were analyzed for the presence of several connective tissue-associated proteins using a dot blot assay. Two such proteins, osteonectin and N-propeptide alpha I type I collagen, were detected in crevicular fluid samples of patients with periodontal disease. Furthermore, the amount of these proteins detected in crevicular fluid appeared to increase with increased probing depth at the sampled site. These studies indicate that measurements of connective tissue-associated proteins in crevicular fluid may prove to be a valuable tool for diagnosing periodontal diseases.

Collagen processing, crosslinking, and fibril bundle assembly in matrix produced by fibroblasts in long-term cultures supplemented with ascorbic acid

Human foreskin fibroblasts were cultured for up to 6 weeks in medium supplemented with ascorbic acid. During this time, the cells produced an extensive new connective tissue matrix in which the accumulated collagen (mostly type I) amounted to about 0.25 mg/10(6) cells. The matrix was highly differentiated as shown by complete processing of procollagen to collagen alpha-chains and covalent crosslinking of the collagen. Alignment of collagen fibrils occurred as the fibrils were deposited between cells, and binding of adjacent fibrils to the cell surface appeared to hold the fibrils in register. Groups of aligned fibrils were subdivided into bundles by cell-surface folds. If beta-aminopropionitrile was added to the medium, collagen crosslinking was inhibited, but not collagen synthesis or fibril bundle organization. If ascorbic acid was omitted from the culture medium, the extensive new connective tissue matrix was not produced. Our results indicate that fibroblasts in long-term cultures supplemented with ascorbic acid produce a connective tissue matrix with many in vivo-like properties including supermolecular organization of collagen.

Coexpression of keratin and vimentin in salivary pleomorphic adenomas

The coexpression of keratin and vimentin is described in 45 pleomorphic adenomas using an immunoperoxidase MAb method. Histopathologically, the outer layer of tubuloductal structures and peripheral tumor cells in solid masses, including modified or neoplastic myoepithelial cells, showed positive staining with monoclonal keratin antibody K8.12 and vimentin. This staining was found in the ratio of 10/26 (38.5%) in tubuloductal structures, 2/7 (28.6%) in peripheral tumor cells and 8/12 (66.7%) in modified myoepithelial cells. Concomitant staining of other keratin antibodies (PKK1, KL1) and vimentin did not exist. In addition, the ductal basal cells of normal salivary glands showed positive K8.12 labelling. The histogenesis of pleomorphic adenoma is discussed in relation to the differentiation of either ductal basal cells or ductal luminal cells from a single stem cell origin or the direct transformation of ductal basal cells to outer tumor cells and/or modified myoepithelial cells, both coexpressing K8.12 and vimentin.

A biochemical study of glycosaminoglycans in the palatal rugae of the monkey (Macaca fascicularis)

Glycosaminoglycans (GAG) were extracted from the connective tissue of the palatal rugae, separated by electrophoresis and compared with the results obtained for the remaining palatal mucosal and gingival connective tissues. The GAG content of the rugae (3.01 mg/g defatted dry weight) was higher than in the remaining palatal mucosa (2.33 mg/g defatted dry weight) or gingiva (1.68 mg/g defatted dry weight). Dermatan sulphate was the predominant GAG in both the palatal rugae (48% of total GAG) and the remaining palatal mucosa (50%) followed by hyaluronic acid (33 and 31% respectively). The results do not support previous histochemical observations in which the rugae appeared to be rich in hyaluronic acid.

Isolation, purification and partial characterization of novel fluorophores from aging human insoluble collagen-rich tissue

Collagen undergoes progressive browning with aging and diabetes characterized by yellowing, fluorescence and crosslinking, the cause of which remains unelucidated. As an initial step towards understanding the mechanism(s) of insolubilization of collagen in aging, the major fluorophores/chromophores from the insoluble fraction of human dura mater were isolated and their spectroscopic properties were characterized. High molecular weight tryptic peptides of insoluble collagen were cleaved by sequential enzymatic digestion followed by separation into high (HMW) and low molecular weight (LMW) fractions by gel filtration chromatography. LMW was further separated by paper and reverse phase chromatography (HPLC). Two fluorescent peaks, nicknamed P and M, were obtained from LMW which had UV maxima at 325 and 350 nm and excitation/fluorescence maxima at 335/385 and 360/460 nm, respectively. Fluorophore M was borohydride reducible and unstable to acid-hydrolysis, while P remained unaffected. Large quantities of fluorophore M and pyridinoline were found in the highly crosslinked HMW fraction remaining following exhaustive proteolytic digestion. Fluorophore P and M were the major fluorophores recovered from the tryptic digest of insoluble dura mater. Fluorescence spectra of M suggest an iminopropene type of configuration which could result from nonenzymatic browning of collagen with, e.g., glucose or malonyldialdehyde, as a result of lipid peroxidation. Spectroscopic and chemical properties of fluorophore P were reminiscent but not identical with those of pyridinium crosslinks. Structure elucidation of these fluorophores is expected to provide important insight into the aging processes of the extracellular matrix.

[The phosphorus supply of pigs in the body weight category of 11-38 kg. 1. The effect of the phosphorus supply on the performance, nutrient digestibility, protein and fat content in soft tissue and skeleton and protein and fat deposits]

The influence of phosphorus supply on performance and nutrient composition of the empty body was studied in two individual feeding experiments with two and three groups resp. (7 or 8 animals per group). The phosphorus content of the unsupplemented diet was in the experiments I and II 2.97 and 2.41 g/kg, the supplemented phosphorus (as monocalcium phosphate) amounted of 2.5 and 2.33 g/kg diet respectively. The phosphorus supplementation increased live weight gain in both experiments by 84 and 45% and improved feed conversion by 35 and 23% respectively. Phosphorus deficiency did not influence the digestibility of nutrients. The fat content of soft tissue and skeleton of the phosphorus deficient animals was increased. They deposited 0.7 kg more fat (in both experiments) and 1.5 or 0.7 kg less protein in experiment I and II respectively. The utilisation of energy for deposition was not influenced by the different phosphorus supply.

Sirius red polarization method is useful to visualize the organization of connective tissues but not the molecular composition of their fibrous polymers

There are several reports in the literature where the sirius red polarization method is used to identify the molecular type of collagen in tissue sections. We present evidence that such way of interpretation is erroneous. The sirius red polarization method is useful to visualize the organization of connective tissues and not to identify the molecular nature of their fibrous polymers.

Connective tissue, mechanical, and morphometric changes in the lungs of weanling rats fed a low protein diet

We studied the effect of low-protein diet (8% casein) on lung growth in rats from 3 to 7 weeks of age. Their diet was isocaloric with that of control animals fed a diet of 20% casein. The calorie intake of experimental animals was increased during the first 3 weeks of the experiment, but they increased less (about 10%) in body weight, had less protein and less water when the whole body was examined, and had lower serum proteins and decreased urinary hydroxyproline. The experimental animals remained in positive nitrogen balance by maintaining low urinary nitrogen excretion. The lungs of the experimental animals were abnormal, with decreased absolute amounts of hydroxyproline and desmosine and of these relative to unit lung weight. The lungs contained more air per gram of lung tissue, and the volume of air in the lung was increased at all transpulmonary pressures above zero. When corrected for increased total lung capacity, there was a loss of recoil at mid-lung volumes. Saline-filled volume-pressure curves, corrected for lung volume, showed similar loss of recoil. Alveolar multiplication was quantitatively normal, but the experimental animals had larger alveoli. We conclude that the protein deprivation in isocalorically fed animals has a specific effect on lung scleroprotein content, which may be due to diminished synthesis, and this results in both structural and functional abnormalities in the lung. Our results indicate the importance of dietary protein in lung development and possibly as one of the causes of emphysema. Further studies are needed to know whether this would be a problem in infants of Kwashiokor.

Mast cell heterogeneity in the small intestine of normal, gnotobiotic and parasitized pigs

A formalin fixative and a formalin-free fixative were used to study mast cells in the small intestine of conventional, gnotobiotic and parasitized pigs. Many more mast cells were identified after basic lead acetate fixation ('mucosal mast cells', MMC) than after routine formalin fixation ('connective tissue mast cells'). The MMC were preferentially localized in the lamina propria. There were no differences between conventional and gnotobiotic pigs. However, in parasitized animals, the number of mast cells was several times higher, mainly because there were more MMC. The heterogeneity of intestinal mast cells in the pig indicates that this might be an interesting model for functional studies on mast cell subsets.

Numbers and heterogeneity of mast cells in the male genital tract of the rat

Normal adult rats were used to quantitate and characterize mast cells in the male genital tract. The tissues were either fixed in a fixative containing formalin (Schaffer solution) or with basic lead acetate (BLA) to identify 'connective-tissue mast cells' and 'mucosal mast cells', respectively. In the epididymis and seminal vesicle small numbers of mast cells were identified without any obvious heterogeneity. In the prostate, however, a mean of 45.1 +/- 9.3 and 23.0 +/- 4.0 mast cells/mm2 was found after BLA and Schaffer fixation, respectively. This difference might be of functional and clinical significance.

Ehlers-Danlos syndrome type IV (EDS IV) as model of a defective biopolymer composite material

The connective tissue of a lethal EDS IV case was investigated for the reasons of the manifested disturbances of the arterial wall. This functional disorder was attributed to the mechanical decoupling of elastin and collagen, with the premise of a composite material consisting of cellular, fibrillar, lamellar and other matrix components. A conceivable relation between the manifested deficiency of type III collagen and a disturbed anchoring of elastin is shown. These findings are supported by biochemical, morphological, x-ray and mechanical data.

Effect of intermittent stretch on immobilised muscle

When muscle is immobilised in a shortened position there is a reduction in fibre length and an increase in the proportion of connective tissue. This results in reduced muscle compliance and a loss of range of joint motion. Experiments have been carried out to determine whether short periods of stretch are effective in preventing these changes. The soleus muscle of the mouse was immobilised in a shortened position for a period of 10 days by means of a plaster cast. Every two days the cast was removed and the muscle passively stretched for a 15 minute period. It was found that this treatment prevented the connective tissue changes but did not prevent the reduction in muscle fibre length, which in itself resulted in considerable loss of range of motion.

Localization of a renal kallikrein immunoreactive-like substance in rat ureter

An antibody against rat kallikrein was produced in rabbits and its localization was studied in various organs of the rat to confirm its specificity. The distribution of immunoreactive kallikrein was studied in rat ureter by use of immunochemical techniques. Ureteral tissue was fixed in Zamboni's-glutaraldehyde fixative and immunostained with indirect immunofluorescence and the peroxidase-antiperoxidase (PAP) method for light and electron microscopy. Preabsorption of the primary polyclonal antiserum with purified rat urinary kallikrein and substitution with normal serum were used as controls. By light microscopy, kallikrein was localized in the lamina propria and in the adventitial connective tissue surrounding the entire ureter. Immunoelectron microscopy confirmed this immunolocalization. Immunoreactive kallikrein was concentrated in fibroblasts of connective tissue and was not present in collagen fibers. Immunoreactivity was associated with the Golgi complex, free polyribosomes, and rough endoplasmic reticulum. No immunostaining was observed in other subcellular components of fibroblasts.

A parallel between two techniques of extraction of connective tissue macromolecules

A method of extraction of the collagen and noncollagen proteins from deep dermis of young adult rabbits using a 0.1 M tartaric acid solution was set up. The tartaric acid extraction, together with the preliminary neutral salt extraction, solubilized 95% of the total collagen and 98% of the noncollagen proteins, far more than the 6 M guanidinium Cl solution used for comparison. Elastin was not extracted. Studies on the fibrillation of the extracted collagen in neutral solution at 25 degrees C or on the results of pepsin digestion in acidic solution at +4 degrees C showed that the tartaric acid-extracted collagen was in a nondenatured form, whereas that extracted by guanidinium Cl was largely denatured. Polyacrylamide gel electrophoresis (PAGE) indicated that most of the collagen was of type I and that many noncollagen proteins were present, mostly in the molecular weight range of 40 kDa. Bidimensional PAGE gave a reproducible pattern of these noncollagen proteins, showing that several additional proteins were present in tartaric acid extracts and not in guanidinium chloride extracts.

Fatty acid composition of fats of differing melting points extracted from ram subcutaneous tissue

The observation that the subcutaneous fat of pasture-fed Southdown rams consists of two distinct regions is reported. Fatty acid composition of fat from the outer and inner regions of subcutaneous tissue taken from the rib region of eight Southdown rams fed pasture were determined. Relative to the harder inner regions (mean melting point 43.1 degrees C), the softer outer regions (mean melting point 31.8 degrees C) were shown to contain more 9:0-, 15:0-, 17:0-, 17:1-, 18:1-cis and total 18:1 fatty acids; less 14:0-, 16:0-, 18:0- and 18:1-trans fatty acids; and a greater variety and a greater concentration of branched-chain components. Proportions of medium chain-length fatty acids, other than 9:0, did not differ between the layers. The fatty acid contents of serial samples taken at 1-mm intervals through these tissues were determined. Changes in concentrations of components among samples were gradual through the tissues. There was no clear connective tissue sheet, as has been reported for pigs. The inner region of the tissues contains apparently nonrandom fluctuating changes in fatty acid composition.

Identification of collagen, elastic, elaunin and oxytalan fibres in ganglia of the myenteric plexus of the human oesophagus

The connective tissue associated with the myenteric plexus of the human oesophagus was studied by light and electron microscopy. Collagen fibres were identified by picrosirius staining with polarization microscopy and from their fine structural morphology. A capsule of connective tissue invests the ganglia while septa of connective tissue separate groups of ganglion neurons, surrounding each individual ganglion neuron and each nerve bundle. Collagen fibrils surround the ganglia, each ganglion neuron and each nerve bundle. The fibrils are disposed in various orientations forming networks. Elastic, elaunin and oxytalan fibres were identified by their staining characteristics and fine structural morphology. The bulk of the ganglion sheath consists of coarse elastic fibres and elaunin fibres. Elaunin and oxytalan fibres form the intraganglionic network. Oxytalan, elaunin and elastic fibres appear to be located in areas related to different stresses and deformation to which the ganglia of the myenteric plexus are exposed during the contraction of the esophageal wall. The ganglia of the myenteric plexus of the human oesophagus show structural organisation of the connective tissue component similar to that seen in sympathetic and parasympathetic ganglia.

Connective tissue of rat lung. II: Ultrastructural localization of collagen types III, IV, and VI

We localized collagen types III, IV, and VI in normal rat lung by light and electron immunohistochemistry. Type IV collagen was present in every basement membrane examined and was absent from all other structures. Although types III and VI had a similar distribution, being present in the interstitium of major airways, blood vessels, and alveolar septa, as in other organs, they had different morphologies. Type III collagen formed beaded fibers, 15-20 nm in diameter, whereas type VI collagen formed fine filaments, 5-10 nm in diameter. Both collagen types were found exclusively in the interstitium, often associated with thick (30-35 nm) cross-banded type I collagen fibers. Occasionally, type III fibers and type VI filaments could be found bridging from the interstitium to the adventitial aspect of some basement membranes. Furthermore, the association of collagen type VI with types I and III and basement membranes suggests that type VI may contribute to integration of the various components of the pulmonary extracellular matrix into a functional unit.

Connective tissue alterations in the skin of ultraviolet irradiated hairless mice

Connective tissue alterations were induced in hairless mouse skin by ultraviolet (UV) irradiation. Hairless mice were irradiated three times a week for 10 weeks with sunlamps (UVA and UVB) and the skin was examined using immunochemical and biochemical techniques. Indirect immunofluorescence was performed with antibodies directed against elastin, microfibrillar proteins, and fibronectin. Increased fluorescence was observed in the actinically damaged skin for elastin, microfibrillar proteins, and fibronectin. The elastic fiber components, elastin and microfibrillar proteins, were then isolated and quantified. Control skin contained approximately 0.1% by dry weight of elastic fiber components, whereas actinically damaged skin contained 0.2% by dry weight. These data are consistent with previous observations of elastic fiber hyperplasia in UV irradiated mice. In addition, irradiated mouse skin contained 1.12 mg of extracted fibronectin per gram wet weight as compared with 0.59 mg in control skin. Irradiated mouse skin contained increased quantities of hyaluronic acid and chondroitin sulfate (uronic acid content). These studies further support the validity of the UV irradiated hairless mouse as a model of human dermal photoaging.

Alteration of the collagen type III/type I ratio and intracranial saccular aneurysms in GH-secreting hypophyseal adenomas

In reporting a case of GH-secreting hypophyseal adenoma associated with a carotid-ophthalmic aneurysm we discuss the possible relevance of an alteration of the type III to type I ratio in arterial wall collagen to the formation of intracranial aneurysms, known to be multifactorial in mechanism. The increased turnover of collagen and the type III collagen deficiency in the vessel wall present in acromegaly suggest that this secondary connective tissue change may have a role in the formation of intracranial aneurysms in patients with GH-secreting hypophyseal adenoma.

Isolation of noncollagenous proteins from gingival connective tissue

Noncollagenous proteins form an integral part of gingiva and other connective tissues. We have performed studies aimed at purification and partial characterization of the gingival noncollagenous proteins. Healthy gingival tissues from mongrel dogs were extracted in neutral buffers, acetic acid, and 6 mol/L urea. Immunoblots using anti-keratin antibodies and CNBr peptide patterns revealed that the majority of the proteins present in these extracts were keratins. To exclude keratins, gingival connective tissue was separated from the epithelium and then extracted. Acid extracts of the connective tissue contained very little protein, whereas urea extracts contained collagen and other noncollagenous proteins. The noncollagenous proteins present in the urea extract were partially purified by DEAE-cellulose chromatography and separated by affinity chromatography through a Sepharose 4B-type I collagen column. At least eight proteins, which ranged in molecular size from 15 to 75 kilodaltons, were obtained by this procedure. We conclude that keratins are major components of whole gingiva extracts and that epithelium must first be removed in order for connective tissue proteins to be obtained. The gingival connective tissue appears to contain several collagen-binding proteins, and these proteins may play an important role in the structure and function of the gingival matrix.

Identification and subcellular location of talin in various cell types and tissues by means of [125I]vinculin overlay, immunoblotting and immunocytochemistry

In the present study, we have examined the cellular and subcellular distribution of talin in several tissues of the chicken. By immunocytochemistry, Western Blot analysis and [125I]vinculin overlay, talin was demonstrated in most of the main tissues and cell types of the body. Corresponding to the property of talin to bind to the fibronectin receptor, talin was found to be confined to the site of the plasma membrane that abuts the extracellular matrix in various types of mesenchymal and epithelial cells. In the central nervous system talin was almost exclusively confined to cells of the connective tissue, i.e., blood vessels and the connective tissue sheaths. No evidence was obtained for the association of talin with any type of intercellular junction. In nonadhering cells such as circulating platelets and leukocytes, talin displayed a diffuse distribution throughout the cytoplasm. These findings suggest a general role for talin in certain aspects of cellular adhesion to the extracellular matrix.

Receptor for plasmin on human carcinoma cells

We have shown that cells from human tumor cell line SW 1116 have receptors for plasmin and plasminogen. These receptors are the same for the proenzyme and the enzyme, but they have a much higher affinity for plasmin (Kd = 6 X 10(-8) M) than for plasminogen (Kd = 5 X 10(-6) M). Plasminogen binding was strongly increased by preincubation of the tumor cells with urokinase and was inhibited by anti-urokinase serum. Because free plasmin is rapidly neutralized in vivo, it is likely that, under physiological conditions, plasminogen is bound by tumor cells and partially transformed into plasmin by urokinase already present at the surface of these cells. Bound plasmin retains its enzymatic activity, which demonstrates that its binding does not involve the enzyme's active site.

Cellular localization of bovine pancreatic trypsin inhibitor and related molecular forms in bovine lung

In addition to bovine pancreatic trypsin inhibitor (BPTI), three BPTI-related molecular forms (isoinhibitors I, II and III) were isolated from bovine lung by affinity chromatography on immobilized trypsin and subsequently purified by Fast Protein Liquid Chromatography. These inhibitors are identical to the isoinhibitors previously isolated from bovine spleen. Their localization in bovine lung was studied by immunohistochemical techniques, using two different immunoglobulin preparations, selectively recognizing BPTI or the other molecular forms. BPTI-related immunoreactivity was found to be restricted to isolated cells, often identified as mast cells by Toluidine Blue staining. In contrast, isoinhibitor-related immunoreactivity, which also occurs in the mast cells, is present in a number of other cell types. These types include: (i) the smooth muscle cells of different calibre vessels, (ii) the ciliated cells of the bronchial epithelium and the related mucus, and (iii) many cells at alveolar level. Comparison of these data with previous results obtained for bovine spleen suggest multiple physiological roles for these inhibitors.

Metallic wear in failed titanium-alloy total hip replacements. A histological and quantitative analysis

We conducted extensive histological examination of the tissues that were adjacent to the prosthesis in nine hips that had a failed total arthroplasty. The prostheses were composed of titanium alloy (Ti-6Al-4V) and ultra-high molecular weight polyethylene. The average time that the prosthesis had been in place in the tissue was 33.5 months (range, eleven to fifty-seven months). Seven arthroplasties were revised because of aseptic loosening and two, for infection. In eight hips cement had been used and in one (that had a porous-coated implant for fifty-two months) no cement had been utilized. Intense histiocytic and plasma-cell reaction was noted in the pseudocapsular tissue. There was copious metallic staining of the lining cells. Polyethylene debris and particles of cement with concomitant giant-cell reaction were present in five hips. Atomic absorption spectrophotometry revealed values for titanium of fifty-sic to 3700 micrograms per gram of dry tissue (average, 1047 micrograms per gram; normal, zero microgram per gram), for aluminum of 2.1 to 396 micrograms per gram (average, 115 micrograms per gram; normal, zero micrograms per gram), and for vanadium of 2.9 to 220 micrograms per gram (average, sixty-seven micrograms per gram; normal, 1.2 micrograms per gram). The highest values were found in the hip in which surgical revision was performed at fifty-seven months. The concentrations of the three elements in the soft tissues were similar to those in the metal of the prostheses. The factors to which failure was attributed were: vertical orientation of the acetabular component (five hips), poor cementing technique on the femoral side (three hips), infection (two hips), and separation of a sintered pad made of pure titanium (one hip). A femoral component that is made of titanium alloy can undergo severe wear of the surface and on the stem, where it is loose, with liberation of potentially toxic local concentrations of metal debris into the surrounding tissues. It may contribute to infection and loosening.

Quantitation of elastin in human urine and rat pleural mesothelial cell matrix by a sensitive avidin-biotin ELISA for desmosine

A specific enzyme-linked immunosorbent assay (ELISA) was developed for the determination of desmosine, a cross-linked amino acid specific to fibrous elastin. Competition between solid phase-bound desmosine-protein conjugate and free desmosine for binding to monospecific anti-desmosine antiserum constituted the underlying principle of the assay. The conjugation of desmosine to different protein carriers was carried out with the 1-ethyl-3-(dimethylamino-propyl)carbodiimide (ECDI); rabbits were immunized with desmosine-bovine serum albumin and micro-titer plates were coated with desmosine-egg albumin. An avidin-biotin peroxidase system was used to reveal anti-desmosine antibodies bound to the desmosine-protein conjugate. As both conjugates revealed new non-specific common epitopes on the carrier proteins, prior absorption of the anti-desmosine antiserum on rabbit albumin polymerized with ECDI was required to remove the antibodies directed against these neo-antigens. The absorption procedure resulted in an increased specificity and sensitivity. Values ranging from 0.07 to 4 ng of desmosine/well could be detected and this sensitivity was greater than that obtained in previous immunoassays for desmosine. In order to assess the specificity of the test, samples containing aminoacids and urine hydrolysates were included in an assay. Some cross-reactivity was observed with the desmosine precursor lysinonorleucine and the desmosine isomer isodesmosine but, in contrast the very low cross-reactivity observed with collagen hydrolysate was similar to that exhibited by albumin hydrolysate. Analysis of urine samples from 118 normal male volunteers showed, firstly, that urinary creatinine measurement was a good indicator of the amount of urine which could be safely introduced in the assay without risk of non-specific interference by other organic compounds and, secondly, that the desmosine/creatinine ratio was a reliable index for an in vivo assessment of degraded elastin excretion. The assay also allowed quantitation of elastin fiber biosynthesis in the connective tissue matrix of cultured rat pleural mesothelial cells. This ELISA for demosine is a simple technique which should be useful for further in vivo or in vitro investigations of fibrous elastin tissue metabolism.

Normal wound healing compared to healing within porous Dacron implants

This study examined the hypothesis that healing within porous implants differs from that in normal connective tissue. Special attention was given to extracellular components including collagen, reticular fibers, and ground substance, and to enzymes associated with activated macrophages. Using Dacron velour and the rabbit as host, the healing of normal connective tissue and that of the tissue/implant interface were histologically compared 10 and 28 days postimplantation. The results exhibited significant differences between connective tissue healing, implant capsule formation, and granulation tissue generation. The healing of connective tissue and implant capsule formation were essentially complete at 28 days. However, tissue inside the implant was qualitatively different and did not significantly change between 10 and 28 days. It was characterized by macrophages and giant cells, a predominantly acid mucopolysaccharide ground substance, and qualitatively fewer and less well defined collagen and reticular fibers were observed than in normal wound healing. Thus we conclude that the connective tissue inside Dacron velour does not resemble normal connective tissue after 10 or 28 days of healing. Furthermore, the collagen never fully matures into orderly bundles, a phenomenon which may be related to an altered mucopolysaccharide composition and a diminished reticular network. The lysosomal enzymatic activity of the macrophages and perhaps the giant cells at the tissue/implant interface may be linked to these differences.

Connective tissue remodelling in the ovine cervix during pregnancy and at term

Cervical ripening and dilation in the ewe has been quantitated in terms of the connective tissue content of the tissue and the biosynthesis of the macromolecular components which make up the extracellular matrix of this tissue. During pregnancy there is a marked increase in the total tissue mass of the cervix along with the total mass of hydroxyproline (collagen) and hexuronate (proteoglycans and hyaluronate). The concentration of hydroxyproline of the cervix based on wet weight of the tissue decreases during pregnancy, however if based on dry weight, the concentration does not change until term. The hexuronate concentration based on both wet and dry weight of the tissue declines with pregnancy. The biosynthesis of collagen does not change during pregnancy but the rate of hyaluronate and proteoglycan synthesis by the cervix is increased in late pregnancy, and at term the rate of proteoglycan biosynthesis is elevated 10-fold. These data suggest that during cervical ripening and dilation a highly dynamic metabolic state exists within the tissue which allows for rapid tissue remodelling.

Calcitonin and granulation tissue formation in the rat. An experimental study

The effects of systemically administered calcitonin (CT) on granulation tissue development were compared using viscose cellulose sponges as wound model in the rat. The ingrowth of new granulation tissue was analyzed for the contents of various connective tissue components (total nitrogen, hydroxyproline, DNA, and RNA) and for the differential counts of the cells infiltrating the sponges. The results indicate that up to 4 weeks postoperatively (p.o.) CT did not affect the net amount of collagen, measured as hydroxyproline, total nitrogen, aminosugars nor the dynamics of differentiation and viability of the invading cells. The present observation that CT has negligible effects, if any, on the early stages of connective tissue formation and on the cell population indicates that surgical procedures could be carried out safely during systemic CT therapy without an increased risk of wound complications.

Quantification and analysis of the glycosaminoglycans in human odontogenic cyst linings

Glycosaminoglycans (GAG) were extracted from the connective tissue of 15 dental cysts, 2 dentigerous cysts and 7 keratocysts, and separated electrophoretically and chromatographically. Hyaluronic acid (dental, 2.38; dentigerous, 3.98; keratocyst, 3.19 micrograms uronic acid/mg lyophilized tissue) was the major GAG detected, with lesser amounts of heparin (dental, 1.70; dentigerous, 1.95; keratocyst, 1.80 micrograms uronic acid/mg lyophilized tissue) and chrondroitin-4-sulphate (dental, 1.33; dentigerous, 2.85; keratocyst, 1.37 micrograms uronic acid/mg lyophilized tissue). It is suggested that enzymic release of these GAGs allows their diffusion into the luminal fluid where they may contribute to expansile cyst growth.