Elastic anisotropy of bivalve hinge-ligament

Compressive stress-strain properties of an elastic ligament of a bivalve, Pseudocardium sachalinensis were investigated in the swollen state in water. The ligament is a calcified tissue, composed of calcium carbonate and insoluble protein which is rich in methionine S-oxide residue [Kikuchi, Y. and Tamiya, N., J. Biochem. (Tokyo) 89, 1975-1976 (1981)]. X-ray diffraction study showed that calcium carbonate existed only in orthorhombic aragonite form, and that all the crystal c-axes of the unit cell orientate nearly in the growing direction of the ligament. The uniaxial compression modulus for the growing direction was appreciably larger than those for the other two directions, while the anisotropy of the modulus was absent for a decalcified ligament. Thus the mechanical anisotropy of the ligament could be explained by means of the uniaxially oriented structure of aragonite crystals being dispersed in a nearly isotropic protein matrix.

Hereditary amyloidosis: evidence against early amyloid deposition

Twelve members of the Indiana hereditary amyloidosis type II kindred were tested for the presence of amyloid deposits. All were young adults (age 26-37), with no evidence of disease and with 1 affected parent. Six were found to be carriers of the variant gene, by DNA testing and/or reduced serum retinol-binding protein levels. Nevertheless, no amyloid could be found in any skin, rectal, or carpal tunnel biopsy specimens. Our results suggest that hereditary amyloidosis type II is a true late-onset disease, in which accumulation of amyloid does not start until late in life--perhaps only a short time before symptoms appear.

Developmental regulation of the mRNAs for elastins a, b and c in foetal-calf nuchal ligament and aorta

The data presented clearly suggest that relative amounts of mRNAs for elastins a, b and c are developmentally regulated in foetal-calf nuchal ligament and aorta and that this regulation is tissue-specific. In nuchal ligament, at earlier stages of foetal development, the relative amounts of mRNAs for elastins a and b are very low. After the foetal age of about 6 months the relative amount of mRNA for elastin b begins to increase. This is followed by an increase in the relative amount of mRNA for elastin a. In aorta, with increasing foetal age, the relative amounts of mRNAs for elastins b and c increase and decrease alternately. The relative amounts of mRNA for elastin a remain low, with only marginal increases with foetal age. A possible self-aggregation role of elastin a in elastogenesis is proposed.

Amyloid localized to tenosynovium at carpal tunnel release. Natural history of 124 cases

One hundred fifty-two patients with amyloid in the tenosynovium who had carpal tunnel release were identified. Twenty-eight patients were excluded because of systemic amyloidosis: primary systemic amyloidosis (AL) in 24, secondary amyloidosis (AA) in 3, and familial amyloidosis (AF) in 1. The remaining 124 patients (82%) had carpal tunnel syndrome with local deposition of amyloid and no evidence of systemic amyloidosis. Median survival of the 124 patients from diagnosis of amyloidosis was 12 years. Only two patients had systemic amyloidosis develop--9 and 10 years after recognition of tenosynovial amyloid. Of particular interest were 12 patients who had an M-protein in the serum or urine. None of the 12 patients have had evidence of systemic amyloidosis or multiple myeloma during the median follow-up of 14 years. The authors conclude that amyloid may be localized to the tenosynovium and that systemic amyloidosis rarely develops during long-term follow-up.

The protein components of the 12-nanometer microfibrils of elastic and nonelastic tissues

A procedure has been developed which is much more specific for the solubilization of the elastin-associated microfibrils from fetal bovine nuchal ligament using treatment with reductive saline in place of reductive guanidine hydrochloride buffer. When analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, reductive saline extracts were shown to contain only five major protein bands with Mrs of 340,000, 78,000, 70,000, 31,000, and 25,000. The 31-kDa species was identified immunologically as the previously described macromolecule named microfibril-associated glycoprotein (MAGP) (Gibson, M. A., Hughes, J. L., Fanning, J. C., and Cleary, E. G. (1986) J. Biol. Chem. 261, 11429-11436). The proteins were purified by gel permeation, ion exchange, and affinity chromatography. Amino acid analyses showed that each protein had a profile which was distinct from that of MAGP although each was also high in acidic amino acids and cystine. The 340- and 78-kDa species were each demonstrated by immunoelectron microscopy with affinity-purified antibodies to be derived from the elastin-associated microfibris, and these were provisionally named microfibrillar protein 340 (MP340) and microfibrillar protein 78 (MP78), respectively. Each of the above antibodies gave a tissue distribution identical to that of anti-MAGP antibodies, and thus MP340 and MP78 also were identified with the 12-nm microfibrils of nonelastic tissues. MP340 was shown to absorb out completely the microfibrillar immunoreactivity of anti-(reductive guanidine hydrochloride extract) antibodies, indicating that MP340 was (a) the major microfibrillar constituent in these extracts and (b) the second unidentified microfibrillar antigen described previously. The relationship of the 70- and 25-kDa proteins to microfibrils is yet to be established. Immunoblot and immunoabsorption studies showed that MAGP and MP78 were immunologically related to MP340 but not to each other. Cyanogen bromide peptide mapping indicated that MAGP was structurally related to MP340. It is postulated that MAGP and MP78 are constituents of MP340 which in turn is the subunit of which the 12-nm microfibrils are composed.

Collagen types I and III and fibronectin in healing anterior cruciate ligament after reconstruction with carbon fibre

The presence of the connective tissue components fibronectin and collagen types I and III have been demonstrated by immunohistological methods after reconstruction of the anterior cruciate ligament of pigs with carbon fibre. The carbon fibre ligament prosthesis was covered with pediculated fascia lata. During the initial 16-week period, fibronectin was seen both in the surrounding fascial layer and between the carbon fibres of the substitute. Type III collagen was also found, especially in the fascial layer, but collagen was absent from the carbon fibre prosthesis and was seen only in the fascial layer. Results indicate that the tissue in the 'neoligament' after carbon fibre reconstruction consists mostly of granulation tissue with a high amount of fibronectin, and type III collagen from mesenchymal cells without sufficient amount of type I collagen with tensile strength to withstand subsequent mobilization and rehabilitation.

Distribution of 35S-sulfate within the transseptal ligament of the mouse

The distribution of 35S-sulfate-labeled macromolecules was examined within three regions of the transseptal ligament: the 1) mesial, 2) middle and 3) distal thirds. Swiss mice, 6 weeks of age, were injected with 35S-sulfate and killed after 1, 6, and 12 hours and 1, 2, 3, 4, 5, and 7 days. Silver grains and cell nuclei were counted on autoradiographs which had been counterstained by the Van Gieson method, and mean counts were analyzed statistically. Analysis of variance revealed no significant differences in mean number of cell nuclei between regions throughout the course of the experiment. 35S-sulfate was rapidly incorporated into the transseptal ligament macromolecules. Grain counts were highest 6 hours after injections: counts were highest over the middle and lowest over the mesial thirds of the ligament. The rate of grain removal was significantly higher in the middle third compared to the mesial or distal thirds (P less than 0.001) and was significantly lower in the mesial third compared to the middle or distal thirds (P less than 0.001). The half-life of labeled macromolecules was significantly greater in the mesial and distal thirds than in the middle third (P less than 0.005). The data demonstrate significantly higher rates of turnover of 35S-sulfate-labeled macromolecules in the middle region of the transseptal ligament. Since cellular density was similar throughout the transseptal ligament, higher turnover rates of 35S-sulfate-labeled macromolecules probably indicate higher rates of cellular activity in this region, possibly a result of tissue remodeling coincident to stresses generated by occlusal forces and physiologic drift of the adjacent teeth.

A reevaluation of the distribution of 3H-proline in the transseptal ligament of the mouse in radioautography

It is generally accepted that there is uniform collagen metabolism within the periodontal and transseptal ligaments. The present study suggested regional variations in the incorporation and removal of 3H-proline within the transseptal ligament in radioautography, suggesting variable rates of collagenous protein remodeling coincident with physiological tooth movements. Highest numbers of silver grains were over the middle third of the ligament during both incorporation and removal phases (p less than 0.001). Rates of grain removal were greater in the middle than in mesial or distal thirds (p less than 0.001). The half-life of labeled proteins was significantly less in the middle than in mesial or distal thirds (p less than 0.005). Because there were no significant regional differences in cell numbers, regional variability in grain incorporation and removal within the transseptal ligament likely indicates regional differences in cellular synthetic or degradative activity coincident with remodeling of the transseptal ligament during physiological drift and suggests that the center of this ligament may experience more stress and, thus, remodels more rapidly.

Post-embedding methods for immunolocalization of elastin and related components in tissues

Elastic tissue is composed of amorphous-appearing elastin and 12-nm diameter microfibrils, one component of which has recently been isolated and characterized as the 31 KD microfibril-associated glycoprotein MAGP. Monospecific antibodies to each of these components have been developed in this laboratory. The parameters that determine optimal localization of colloidal gold probes for post-embedding immunolabeling of elastic tissue components have been systematically studied in a variety of normal and developing tissues in mammals and birds. Protein A-gold probes stabilized with dextran have been shown to provide complexes that remain stable after more than 2 years. Conditions have been defined that permit precise localization within the extracellular matrix of antibodies to MAGP and to elastin, singly and together. Best results were obtained with acrylic resins (Lowicryl K4M or LR White). Fixation in glutaraldehyde or other aldehydic fixatives, with or without osmium, did not affect the immunostaining of elastic tissue with affinity-purified antibodies to tropoelastin, or to anti-[alpha-elastin] or anti-[alkali-insoluble elastin]. Immunostaining with the anti-MAGP antibody was less robust and was possible in tissues which had been fixed only lightly before embedding in Lowicryl K4M or LR White. This staining was enhanced by metaperiodate oxidation of the sections as well as by reduction of the tissues with sodium borohydride en bloc, followed by hyaluronidase digestion of the sections. The effects on immunostaining of a range of enzyme digestions have also been examined. Conditions have thus been defined that make possible detailed study of the relationship between elastic tissue, elastin-associated microfibrils, and other microfibrillar structures in normal and abnormal tissues during development and aging.

The diaphragm: anatomic, pathologic, and radiologic considerations

The diaphragm, by virtue of its complex anatomy and multiple ligamentous connections to both thoracic and abdominal structures, is more than a simple partition between the chest and abdomen. Cross sectional images of the diaphragm and peridiaphragmatic processes can be confusing unless the radiologist is aware of the normal structure of the diaphragm, its attachments to the body wall, and the multiple ligaments that attach to the diaphragm.

[A histochemical study of acid glycosaminoglycans on normal and pathological cartilage, ligaments and several other connective tissues]

Histochemical estimation of acid glycosaminoglycan was critically re-evaluated, using the meniscus, intervertebral disc, ossified yellow ligament, ganglion, Dupuytren's fascia and several other tissues. Each tissue was stained with toluidine blue, alcian blue, high iron diamine, low iron diamine, aldehyde fuchsin and dialyzed iron-ferrocyanide. Digestion techniques for GAG were used in these staining methods, and the effects of protease inhibitors (PI) on digestion were also examined. In this study, the optimal temperature for digestion with Streptomyces hyaluronidase was between 37 degrees C and 43 degrees C, which varied according to the tissue examined. The addition of PI seemed necessary because the enzymatic treatment without PI resulted in an excessive decrease of staining. Protease-free chondroitinase ABC, which did not excessively decrease staining results, was found to be more useful than chondroitinase ABC without PI.

Replacement of the anterior cruciate ligament with a bone-ligament-bone anterior cruciate ligament allograft in dogs

Acute replacement of the canine anterior cruciate ligament (ACL) with a frozen, bone-ligament-bone anterior cruciate ligament preparation was studied using biochemical, immunologic, and biomechanical testing methods. Nine dogs were used for the study, six dogs received allografts and three received autografts. No tissue antigen matching was performed. All nine dogs were killed nine months after surgery. Necropsy examination revealed that the ACL was not present in three joints (one autograft, two allografts). The two autograft and four allograft ligaments available for mechanical testing sustained mean maximum loads that were 10% and 14%, respectively, of the mean maximum loads sustained by the contralateral ACL. Autoradiography indicated that cellular activity was more pronounced in the autograft specimens. Hydroxyproline uptake was 200% and 45% of normal in the autograft and allograft ligaments, respectively. Both autograft and allograft specimens were producing Type I collagen at the time of killing. Antidonor dog leukocyte antigen (DLA) antibody was detected in the synovial fluid taken at the time of killing from six of six dogs that received allografts and in zero of three dogs that received autografts.

Desmosine and isodesmosine as cross-links in the hinge-ligament protein of bivalves. 3,3'-Methylenebistyrosine as an artefact

Desmosine and isodesmosine were detected in an invertebrate molluscan species, i.e. in an insoluble protein in the hinge ligament of a bivalve species, Sakhalin surf clam (Pseudocardium sachalinensis, in family Mactridae). The protein is rich in glycine and methionine S-oxide but devoid of hydroxyproline and hydroxylysine. 3,3'-Methylenebistyrosine was also detected in the HCl hydrolysate of the hinge-ligament protein, but it was found to be an artefact produced from tyrosine and formaldehyde derived from methionine S-oxide during the HCl hydrolysis of the protein.

Chemical taxonomy of the hinge-ligament proteins of bivalves according to their amino acid compositions

The proteins in the hinge ligaments of molluscan bivalves were subjected to chemotaxonomic studies according to their amino acid compositions. The hinge-ligament protein is a new class of structure proteins, and this is the first attempt to introduce chemical taxonomy into the systematics of bivalves. The hinge-ligament proteins from morphologically close species, namely mactra (superfamily Mactracea) or scallop (family Pectinidae) species, showed high intraspecific homology in their compositions. On the other hand, inconsistent results were obtained with two types of ligament proteins in pearl oyster species (genus Pinctada). The results of our chemotaxonomic analyses were sometimes in good agreement with the morphological classifications and sometimes inconsistent, implying a complicated phylogenetic relationship among the species.

Cervical myelopathy attributable to pseudogout. Case report with radiologic, histologic, and crystallographic observations

A 77-year-old woman complained of numbness in her hands and feet, progressive unsteadiness, weakness, and loss of proprioception of six months' duration. A myelogram revealed stenosis of the spinal canal at the levels of C2-3, T6-7, L2-3, and L3-4. On computerized tomography scan, a large dorsal, epidural, soft tissue mass and focal calcification of the ligamentum flavum were seen at C3. Laboratory studies ruled out gout, collagen disease, vitamin B12 deficiency, syphilis, parathyroid, and thyroid disease. At decompressive laminectomy, a nodular mass in the ligamentum flavum (C2-4) was found and removed. Three months after operation, the neurologic symptoms had improved. Histologic examination of the elastic ligament revealed deposits of birefringent crystals, which were identified by X-ray diffraction as calcium pyrophosphate dihydrate (CCPD). Only about six cases of myelopathy attributable to deposits of CPPD appear to have been previously reported.

Isolation and characterization of a pentameric amino acid from elastin

An unknown amino acid was purified from bovine ligament elastin. The compound was shown by proton NMR to have a pyridinium ring structure similar to isodesmosine, yet containing an olefinic double bond on one additional side chain which was not attached to the pyridinium ring. Mass spectral analysis confirmed the NMR data and indicated a parent compound with a mass of 653. A structure is proposed that is derived from the condensation of five lysine residues. The trivial name of pentasine is proposed for this compound.

Elastin in the human intervertebral disk. A histological and biochemical study comparing it with elastin in the human yellow ligament

The elastic fiber and elastin in the human yellow ligament and intervertebral disk were studied histologically and biochemically. The elastic fiber in the human intervertebral disk, which until now had not been clearly identified microscopically, was observed clearly. We found the distribution of the elastic fiber in the intervertebral disk to be very sparse and irregular, and its diameter was small, being about one-tenth of that found in the yellow ligament. The elastin contents of the yellow ligament and intervertebral disk were 46.7% +/- 0.9% and 1.7% +/- 0.2% respectively (mean +/- SE) of the total dry weight. The amino acid composition of elastin in the yellow ligament is similar to that of other tissue, as reported in the literature; however, that found in the intervertebral disk is significantly different. It would appear, therefore, that the elastin in the intervertebral disk is of a different type from that found elsewhere.

In vitro mechanical properties of equine tendons in relation to cross-sectional area and collagen content

The mechanical properties of the deep digital flexor tendon (DDFT), the superficial digital flexor tendon (SDFT) and the suspensory ligament (SL) of the hindlimb of the horse were studied in vitro. The tendons were observed at several morphologically distinct sites. The loaded tendon is homogeneously strained, in spite of large variations in cross-sectional area. Consequently the modulus of elasticity was inversely proportional to the corresponding cross-sectional area and ranged from 738 MPa (megaPascal, N mm-2) to 1398 MPa within the DDFT, from 1000 MPa to 1282 MPa within the SDFT and from 576 MPa to 669 MPa within the SL. The collagen content was inversely proportional to the cross-sectional area and proportional to the modulus of elasticity. This stresses the influence of tendon composition on the mechanical properties, and also demonstrates the difficulty in judging the strength of a particular tendon or site within a tendon from its cross-sectional area. The respective tendons ruptured at strains of 10.0 per cent (DDFT), 12.3 per cent (SDFT) and 11.0 per cent (SL). The influence of strain rate on the modulus of elasticity is small, and these tendons may therefore be considered as non-linear elastic structures. The average hysteresis is about 5 per cent.

Axial computed tomographic anatomy of the foot. Part II: Midfoot

Osseous and soft tissue anatomy of the human midfoot is presented as visualized on high resolution axial computed tomography (CT). Because of the proven and potential capabilities of CT in the diagnosis of midfoot disorders, this report serves as an important standard for comparison with clinical studies.

Identification of glycoproteins associated with elastin-associated microfibrils

The microfibrils associated with elastic tissue have been shown to be predominantly proteinaceous. On the basis of their affinity for cationic stains, including ruthenium red, they have been assumed to be glycoprotein, but more evidence to support this claim has not been adduced. Despite repeated investigation of glycoprotein materials obtained by extraction of elastic tissues with reagents that appear to remove microfibrils, the chemical composition of elastin-associated microfibrils remains obscure. An electron microscopic study of the microfibrils in two elastin-rich tissues (bovine nuchal ligament and aorta) during their development was pursued using more specific histochemical methods. The periodic acid-alkaline bismuth stain (analogous to the periodic acid-Schiff stain for glycoproteins in light microscopy) has been adapted for this study. Specific aldehyde groups (confirmed by blocking with m-aminophenol or sodium borohydride) were identified after periodate oxidation as fine granules of bismuth stain. These were shown to localize specifically along the elastin-associated microfibrils in a finely punctate form. Staining of the amorphous elastic component did not occur except for a fine rim adjacent to the microfibrils. Lectin binding with concanavalin A (with ferritin markers) confirmed that there are glucose- or mannose-containing proteins associated with the microfibrillar component of elastic tissue. This was true of these microfibrils in all layers of the aortic wall and throughout the ligament. It was also true of mature adult tissues in which there was a lesser proportion of microfibrils. It is concluded that elastin-associated microfibrils really are associated with glycoprotein(s).

Photolysis and partial ozonolysis of kappa-elastin from ligamentum nuchae

Photolysis and partial ozonolysis of guanidinated kappa-elastin led to the destruction of isodesmosine and desmosine up to 96.0 and 91.5% respectively. Simultaneously there was a 3.89-fold enrichment of the lysine content. Two lysine containing tripeptides and one dipeptide were isolated and characterized. Their amino acid sequences were Gly-Ala-Lys, Gly-Lys-Ala and Lys-Ala, respectively.

Development of elastic fibers of nuchal ligament, aorta, and lung of fetal and postnatal sheep: an ultrastructural and electron microscopic immunohistochemical study

The morphogenesis of elastic fibers of the nuchal ligament, aorta, and lung of sheep was studied by light microscopy, transmission electron microscopy, and immunohistochemical methods for the detection of elastin. The degree of maturation of the amorphous materials of elastic fibers was assessed morphologically in preparations stained by the tannic acid and periodic acid methenamine-silver methods. With both of these methods, the amorphous components of mature fibers stained less intensely than did those of immature fibers. Elastic fibers in early stages of development consisted of many microfibrils and few, small, branching masses of immature amorphous material. Thicker fibers were formed by the coalescence of growing masses of amorphous materials. In late stages of formation of elastic fibers, the mature amorphous materials were associated with few microfibrils; and they were partially surrounded by immature amorphous materials associated with many microfibrils. Antielastin antibody reacted evenly with amorphous materials in very early stages of elastic-fiber development, but reacted only with the other zones of amorphous materials in later stages; it also reacted with the microfibrils in all stages. These findings were interpreted as indicating that the microfibrils were associated with small amounts of elastin on their surfaces. This conclusion is in agreement with ultrastructural observations showing 1) that development of microfibrils precedes that of the amorphous material and 2) that the microfibrils adjacent to the immature amorphous materials are covered with small amounts of tannic acid-positive amorphous materials. These observations suggest that microfibrils serve as sites for elastin deposition, both in early elastogenesis and in subsequent growth of elastic fibers. However, the nature of the interaction between elastin and microfibrils remains unknown.

A collagen-like glycoprotein of the extracellular matrix is the undegraded form of type VI collagen

The 140 000-dalton collagenous glycoprotein (CGP) from calf aorta and ligament characterized by Gibson & Cleary (1982) [Gibson, M.A., & Cleary, E.G. (1982) Biochem. Biophys. Res. Commun. 105, 1288-1295] has been studied. In the electron microscope, rotary-shadowed CGP molecules appear similar to the dimers of type VI collagen (short-chain collagen, intima collagen) described by other authors [Furthmayr, H., Wiedemann, H., Timpl, R., Odermatt, E., & Engel, J. (1983) Biochem. J. 211, 303-311] except that they have larger globular domains. As shown by gel electrophoresis, pepsin treatment of CGP at 4 degrees C either before or after reduction releases polypeptide chains corresponding in size to those of type VI collagen. Electron microscopic examination shows that pepsin digestion of nonreduced CGP removes the outer globular domains, reduces the size of the inner ones, and separates the paired central strands. The residual structures look like type VI collagen dimers. When intact CGP is reduced, monomers with two large globular ends are obtained. Pepsin digestion of monomers removes most or all of both globular domains. In immunoblots, CGP and its pepsin-derived fragments react with antibodies directed against type VI collagen. The results indicate that type VI collagen is an integral component of CGP.

The electron microscopic immunohistochemistry of elastase-treated aorta and nuchal ligament of fetal and postnatal sheep

In conjunction with the immunoperoxidase and the immunoferritin methods, antielastin antibody was used to study the localization of elastin in untreated and elastase-treated elastic fibers of the nuchal ligament and the aorta of fetal and young adult sheep. In tissues not treated with elastase, the staining reaction for antielastin antibody was localized in the outer zones of the amorphous components and along the surfaces of the microfibrils ; the central zones of the amorphous components were unreactive. After mild elastase treatment, incompletely digested amorphous components showed staining both in their central and outer zones, and some of the microfibrils became unreactive. After extensive elastase treatment, small scattered amorphous components were still found in association with bundles of microfibrils. These components were stained diffusely by the antielastin antibody method but were not detectable by staining with uranyl acetate and lead citrate or with Kajikawa 's method for elastin; elastin was not detected on the surfaces of the microfibrils by any of the methods used. These findings were interpreted as indicating that the surfaces of the microfibrils are associated with small amounts of elastin, and that evenly stained amorphous components are composed of elastin, which is loosely arranged and allows the penetration of antielastin antibody. These observations support the concept that microfibrils serve an important role as a scaffold for elastin deposition in elastogenesis. Because of their high sensitivity, immunohistochemical methods for detecting elastin are useful to study partially degraded elastic fibers.

A collagenous glycoprotein found in dissociative extracts of foetal bovine nuchal ligament. Evidence for a relationship with type VI collagen

A collagenous glycoprotein (Mr 140000) was isolated from dissociative extracts of foetal bovine nuchal ligament and purified by a combination of ion-exchange and gel-filtration chromatography. This glycoprotein (designated MFPI) exists as a large-Mr disulphide-bonded aggregate in the absence of a reducing agent. The purified glycoprotein was shown to contain about 6% (w/w) carbohydrate, mostly as galactose, glucose and mannose. Amino acid analysis showed the presence of hydroxyproline and hydroxylysine, indicative of its collagenous nature. The collagenous nature of this glycoprotein was further investigated by enzyme digestion. Pepsin digestion produced three major fragments, which were identical with peptides of type VI collagen. Bacterial-collagenase digestion of the unreduced glycoprotein also produced several discrete peptides. However, reduction of the glycoprotein before bacterial-collagenase digestion resulted in the degradation of these discrete peptides. Glycoprotein MFPI extracted in dissociative conditions appears to be a larger-Mr form of type VI collagen, believed to originate from microfibrillar components in the intact tissue.

Collagen heterogeneity and quantification in developing bovine nuchal ligament

The collagenous components were investigated in peptic digests of developing bovine nuchal ligament. Types I and III collagen were the major species isolated, but the presence of types IV, V and VI was also shown. Changes in the pepsin-susceptibility of nuchal ligament during foetal development were observed. CNBr-cleavage peptide analysis indicated that type I collagen became cross-linked rapidly, as evidenced by the lack of alpha 1(I)CB6. At present it is not clear if this decrease in pepsin-susceptibility is due to cross-linking of collagen, to increased deposition of elastin, or to both. Quantification of collagen types I and III was shown to depend on the method used. When pepsin-solubilized material was examined an apparent increase in type III collagen with respect to foetal age was observed, whereas when CNBr digests of intact ligament were examined a relatively constant amount of type III collagen (approx. 24%) was found. The constant amount of type III collagen observed during foetal development changed at birth and increased in mature nuchal ligament to represent approx. 45% of the total collagen.

Posterior pubo-urethral ligaments in normal and genuine stress incontinent women

Specimens of the posterior pubo-urethral ligament were taken from 10 continent females (7 at post mortem and 3 at gynaecological surgery) and from 9 genuine stress incontinent patients. They were examined and compared using light and electron microscopy and neuro-histochemistry. The morphology of all specimens was similar in that they contained dense connective tissue elements enclosing smooth muscle bundles which were associated with numerous nerves, the enzyme content and fine structure of which were similar to those believed to represent cholinergic autonomic nerves. There was no difference in the morphology, histochemistry and fine structure of the specimens of the ligaments from the control and incontinent patients. Therefore, it is suggested that altered morphology of the posterior pubo-urethral ligaments is unlikely to be an etiological factor in genuine stress incontinence. It is postulated that the ligaments may play a role in stabilising the proximal urethra or assist in bladder-neck opening during voiding.

Variation of elastin fluorescence with method of preparation: determination of the major fluorophore of fibrillar elastin

The variation of fluorescence of two fibrillar elastins as a result of preparation methods was studied and the major common fluorophore was identified. Dilution of acid-hydrolyzed bovine ligament elastin 1:2500 (g:ml) overcame inner filter effects (IFE) to reveal fluorescence excitation and emission maxima of 330/408 nm. An IFE effect observed in elastase-solubilized elastin was unresponsive to dilution. Elastase-solubilized elastin had maximal fluorescence at 338/410 nm (pH 2.3) and 325/394 nm (pH 7.4), and the fluorescence intensity was 35-40% of that of the acid-hydrolyzed elastin. Changes in fluorescence that occurred when an acid hydrolysate was evaporated to dryness were prevented by evaporation to a volume not less than 15 ml. As a result, there was an almost two-fold increase in the yield of a fluorophore with spectral maxima near 340/400 nm. Chick aorta elastin purified by enzymatic methods also contained substantial amounts of this fluorophore. It is concluded that the compound with fluorescence of 340/400 nm is the major common fluorophore of postnatal fibrillar elastins.

Immunohistochemical localization of types I, II, and III collagens in the ossified posterior longitudinal ligament of the human cervical spine

Immunohistochemical localization of types I, II, and III collagen in the ossified posterior longitudinal ligament of the cervical spine was studied using type-specific anticollagen antibodies. In contrast to the normal ligament which contains both types I and III collagens, the ossified matrix, composed of lamellar bone, contains only type I collagen, except for Haversian canals where type III is located in the inner wall. In the transitional region of preossifying ligaments, types III and I are both present. Type II collagen is present in the hyperplastic matrix of the ligament, and cartilage-like cells surrounded by type II collagen are aligned along nonossified ligaments adjacent to the preossifying region. A possible mechanism of matrix transition during the ossification process is given attention.

Non-destructive detection of methionine sulfoxide in the resilium of a surf clam by solid-state 13C-NMR spectroscopy

Methionine sulfoxide was detected in the resilium (internal hinge ligament) of a surf clam by high-resolution solid-state 13C-NMR spectroscopy involving cross-polarization and magic angle spinning, using no chemical procedure. The results support the previous report [Kikuchi, Y. and Tamiya, N. (1981) J. Biochem. (Tokyo) 89, 1975-1976] on a high content of methionine sulfoxide observed by chemical methods in the resilium protein of surf clam species.

Distribution of progesterone in the uterus, broad ligament, and uterine arteries of beef cows

Samples of uterine horn, broad ligament (mesosalpinx and mesometrium), and uterine artery of ten unilaterally ovulating cows, 12-15 days after mating, were examined for differences in concentration of progesterone. Tissues (mesosalpinx, branches of the uterine artery, anterior uterine horn) adjacent to the ovary bearing the corpus luteum contained significantly greater quantities of progesterone than more distal tissues (mesometrium, uterine artery, posterior uterine horn) on the same side and all tissues on the contralateral side. In tissues on the side ipsilateral to the corpus luteum, a gradient of progesterone existed. Differences in tissue concentrations of progesterone may be the cause of observed differences in uterine physiology in the cow and ewe.

Isolation of glycoproteins from bovine nuchal ligament

Soluble substances in the bovine nuchal ligament were removed by preliminary extractions with a buffer and dilute alkali solution. The insoluble residue was then extracted with 6 M guanidine HCl and with 6 M guanidine HCl containing a reducing agent (20 mM dithiothreitol) successively. Each of the two extracts contained a glycoprotein; that in the first extract was designated Glycoprotein A and that in the second Glycoprotein B. They were purified by ion-exchange chromatography and gel filtration till essentially homogeneous. Both proteins had similar molecular weights of 35,000 in SDS-polyacrylamide gel electrophoresis and by gel filtration, and their chemical compositions resembled each other closely. It is suggested that Glycoprotein B was present in the native state as a disulfide-bonded, aggregated form of Glycoprotein A. The compounds also showed similarity with the microfibrillar glycoprotein(s) previously reported in bovine nuchal ligament extracts.

Methionine sulfoxide in the resilium protein of surf clams

A high content of methionine sulfoxide was observed in the resiliums (internal hingeligaments) of surf clams. As no isolation procedure which might cause the oxidation of methionine to methionine sulfoxide was involved and the hydrolysis was carried out in vacuo, it is the first solid evidence for the presence of methionine sulfoxide as a constituent of natural protein.

[[Studies of Ossification of the posterior longitudinal ligament in the cervical spine using microradiography and histochemistry (author's transl)]

ossification of the posterior longitudinal ligament (OPLL) is seen by X-ray as a condition which shows a heterotopically formed bony shadow at the posterior part of vertebral bodies of the cervical spine. OPLL causing severe myelopathy is called a Japanese disease. Recently, it has been shown that this condition is not only seen in Japan, but also in other countries especially in Asia. In order to obtain information of pathogenesis of this condition, the present author carried out histochemical investigations on 2 autopsy cases which had been treated as OPLL myelopathy, and 12 surgical materials. Totally 30 spinal vertebrae were examined. They were prepared for study with undemineralized ground sections mainly. The following results were obtained. 1) Microradiography revealed that the calcified tissue on the ligament had two marked structures, one was highly calcified tissue, and the other was bony tissue with lower density. 2) Most of the highly calcified tissue with variable distribution ranging from a sparse to a dense one contained round radiolucent spots probably consisting of cartilage-like cells. This type of calcified tissue is accompanied by the organic matrix, which was stainable with van Gieson stain, PAS reaction, Alcian blue stain and toluidin blue metachromasia. 3) A part of highly calcified tissue showed linearly distributed pattern without radiolucent round spots. This type of calcified tissue was also stained with van Gieson stain and PAS reaction. However, this organic matrix was not accompanied by marked reaction of acid mucopolysaccharides. 4) No essential histochemical difference was found between the highly calcified tissue on the ligament and other various types of heterotopically formed calcified tissue. 5) Microradiography revealed the remnant of resorption process at the boundary between the highly calcified tissue and the bony tissue. This finding of the resorption lacunae indicated that the highly calcified tissue was formed initially, followed by bone tissue formation. The process of internal remodeling was also observed in the bony tissue. 6) The distribution of the highly calcified tissue, bony tissue and resorption cavities indicated several patterns of remodeling process which was characterized by the new bone formation at the region near the vertebral body. These characteristics were apparently due to the mechanical stresses acting on this bony structures, as seen in some other heterotopic bone formations such as the healing process of fracture or tooth extraction socket.

Partial characterization of peptide fragment purified by isoelectrofocusing after organo alkaline hydrolysis of bovine ligamentum nuchae elastin

Highly purified elastin from bovine ligamentum nuchae was submitted to partial alkaline hydrolysis (37 degree C, 72 H, 1 N KOH in 80 p. 100 aqueous ethanol). The non-coacervable fractions were submitted to isoelectrofocusing and five kappa-elastin fractions were obtained. The amino-acid compositions, the N-terminal amino-acids, the molecular weights and the thermolysin digests of each fraction were determined by various techniques. The average MW was about 14,500 (150 - 166 amino-acids). These results suggest that the distribution of cross-linking agents in fibrous elastin may not be uniform. The results also show that in certain cross-linked regions of similar molecular weight and size appearing to be composed of different polypeptides sequences containing different amounts of cross-links.

Separation of elastin components by thin layer chromatography and electrophoresis

Several methods are described which employ thin layer chromatography and electrophoresis for investigations into the structure and synthesis of crosslinked elastin. These procedures are more sensitive and involve less elaborate equipment than separation on paper. The methods described include an electrophoretic procedure for detecting the cross-linking amino acids in elastin hydrolysates, a method for completely separating desmosine, isodesmosine and merodesmosine in these hydrolysates, and a method for producing two-dimensional peptide maps of elastase digests of elastin.

Specific immunohistochemical localization of type III collagen in porcine periodontal tissues using the peroxidase-antiperoxidase method

Specific antibodies to porcine gingival type III collagen were raised in sheep. After purification on collagen affinity columns the antibodies were used for immunohistochemical localization of type III collagen in porcine periodontal and dental tissues employing the peroxidase-antiperoxidase (PAP) procedure. The extent of staining of the periodontal tissues was found to approximate the amount of type III collagen measured biochemically. A fairly uniform distribution of type III collagen was observed in the periodontal ligament and gingiva with more intense staining often being associated with blood vessels. A regular pattern of weakly staining fibers could be demonstrated throughout the cementum and in parts of the alveolar bone tissue. In addition, occasional sites in the cementum having a different morphological appearance from the rest of the cementum exhibited bundles of positively stained fibers. Although the bone tissue was essentially unstained, fibers in the endosteal spaces stained strongly. Sharpey's fibers passing from the soft connective tissues into alveolar bone and cementum also stained strongly. Three distinct arrangements of collagen fibers stained by the type III collagen antibodies could be identified: first, a reticular pattern, which was seen at the junction of the gingival epithelium and connective tissue, and in the endosteal spaces and dental pulp; second, a more diffuse pattern of fibers intermingled with type I collagen in the soft connective tissues; and third, a coating of some Sharpey's fibers, having a core believed to be type I collagen, and of fibers in the cementum inclusions.

Guanidination of kappa-elastin from bovine ligamentum nuchae

Kappa-Elastin is exhaustively guanidinated in order to chemically modify the pre-existing lysine content to homoarginine. However the pre-existing lysine content is only modified to homoarginine content about 50 p.cent. The other lysyl-bonds are buried or/and engaged to aldi-imine bonds or other bonds. Therefore the first guanidinated kappa-Elastin is submitted to partial acide hydrolysis (HCL, 1 N, 110 degrees C for 2 hours) and submitted to a second exhaustive guanidination. The pre-existing lysin content in kappa-Elastin almost quantitively disappeared and is transformed to the corresponding homoarginine. These results are similar to those obtained by photolysis of (Iso) desmosine residues by UV light which will liberate "new" lysine containing peptides from kappa-Elastin.

The role of Whitnall's ligament in ptosis surgery

Whitnall's ligament has been described functionally as a check ligament of the levator. Our anatomic dissections and operative findings indicate that this ligament is primarily a support for the upper eyelid and superior orbit. Whitnall's ligament is frequently confused with the levator horns and is unfortunately cut during many ptosis procedures. This is to be avoided because much larger levator resections are required when this ligament's support to the upper lid and the fulcrum effect for the levator are lost. Preserving and enhancing the function of Whitnall's ligament improves the efficiency of the levator, making large levator resections rarely necessary. We have noted no more lid lag than that seen with other forms of levator surgery.

A radiographic study of the ligamentous anatomy of the ankle

Ankle trauma commonly results in significant injury. Knowledge of the anatomy of the normally nonopaque major supportive ligaments, and their relationships to the osseous structures seen on standard roentgenograms, facilitates interpretation of both plain films and ankle arthrograms. A group of normal, non-preserved ankles was dissected. The laterally located anterior talofibular calcaneofibular, posterior talofibular, distal anterior tibiofibular ligaments, and the medially located deltoid ligament were carefully defined. They were coated with a mixture of powdered tantalum, photographed, and then radiographed in standard projections. The normal gross anatomy of these major supportive ligaments of the ankle and their relationship to the osseous structures about the ankle are remarkably constant.