Elastic Fiber Staining Research Articles

Wound Healing Process in Post-bariatric Patients: an Experimental Evaluation

Bariatric surgery is the most effective treatment for morbid obesity. Despite this, side effects are recorded. One of them is redundant skin hanging from the patients' body causing both aesthetical and functional deformities. They can only be corrected with body contouring surgery, whose wound complication rate is very high in previously obese population. Despite several hypotheses, an adequate explanation is still awaited. The aim of our study was to evaluate the wound healing process in post-bariatric patients. Seven patients, six women and one man, were enrolled. They all were nonsmokers and nondiabetic. They all underwent biliopancreatic diversion (BPD). After 36months, abdominoplasty was performed. Biochemical parameters before and after bariatric surgery were evaluated. The content of total protein and hydroxyproline was assessed in multiple scar biopsies before and after BPD. Abdominoplasty horizontal scar skin samples were subjected to histological evaluation with Weigert-Van Gieson stain for elastic fibers and connectivum. All biochemical parameters analyzed were reduced post-BPD compared to the preoperative period. Tissue proteins were significantly reduced after BPD both in their totality and as hydroxyproline and hydroxyproline/total tissue protein. Histological evaluation revealed abnormal dermal elastic and collagen fibers. The cause of aberrant healing in massive weight loss body contouring is likely multifactorial. A relationship between nutritional state, wound collagen accumulation, and elastic fiber content seems to be only partially involved. The high mechanical stress of tissues before BPD probably influences the wound healing process after BPD.

Effects of Birth Trauma and Estrogen on Urethral Elastic Fibers and Elastin Expression

To investigate the effects of birth trauma and estrogen on urethral elastic fibers and elastin expression. Pregnant rats were subjected to sham operation (Delivery-only), DVDO (delivery, vaginal distension and ovariectomy), or DVDO + E₂ (estrogen). At 2, 4, 8, or 12 weeks, their urethras were harvested for elastic fiber staining and reverse transcription-polymerase chain reaction analysis. Urethral cells were treated with transforming growth factor- β1 (TGFβ1) and/or estrogen and analyzed for elastin mRNA expression. Urethral cells were also examined for the activities of Smad1- and Smad3/4-responsive elements in response to TGFβ1 and estrogen. At 8 weeks post-treatment, the urethras of DVDO rats had fewer and shorter elastic fibers when compared with Delivery-only rats, and those of DVDO + E₂ rats had fewer and shorter elastic fibers when compared with DVDO rats. Elastin mRNA was expressed at low levels in Delivery-only rats and at increasingly higher levels in DVDO rats at 2, 4, and 8 weeks but at sharply lower levels in DVDO + E₂ rats when compared with DVDO rats at 8 weeks. Urethral cells expressed increasingly higher levels of elastin mRNA in response to increasing concentrations of TGFβ1 up to 1 ng/mL. At this TGFβ1 concentration, urethral cells expressed significantly lower levels of elastin mRNA when treated with estrogen before or after TGFβ1 treatment. Both Smad1- and Smad3/4-responsive elements were activated by TGFβ1 and such activation was suppressed by estrogen. Birth trauma appears to activate urethral elastin expression via TGFβ1 signaling. Estrogen interferes with this signaling, resulting in improper assembly of elastic fibers.

The Role of Oxidative Stress and Inflammation in Conjunctivochalasis

Purpose. To investigate the status of oxidative stress and histopathologic alterations in patients with conjunctivochalasis and compare the findings with those in healthy control subjects. Methods. Eleven patients (n = 20 eyes) with Yokoi grade 3 conjunctivochalasis and 11 health control subjects (n = 22 eyes) were prospectively recruited. ELISA for tear hexanoyl-lysine (HEL) and inflammatory cytokines, tear film break-up time tests, Schirmer test measurements, and fluorescein and rose bengal vital staining were performed. Conjunctival specimens obtained during surgery for conjunctivochalasis and cataract underwent immunohistochemical staining for HEL+8-OHdG, MMP-3, and MMP-9, and positively stained cells were counted. Transmission electron microscopy was also performed, with staining for elastic fibers in the conjunctival stroma. Results. The mean tear stability and vital staining scores were significantly worse in the conjunctivochalasis patients than in the control subjects. The tear HEL and tear cytokine levels showed significantly higher values in eyes with conjunctivochalasis. IL-1beta and IL-6 levels showed a significant correlation with corneal epithelial damage. IL-1beta and TNFalpha showed a significant correlation with 8-OHdG-stained cell counts. Specimens from patients with conjunctivochalasis revealed a significantly higher number of cells positively stained for HEL, 8-OHdG, MMP-3, and MMP-9 than did specimens from age- and sex-matched control subjects. Transmission electron microscopy showed decreased intercellular cohesiveness, with the conjunctival stroma showing an accumulation of elastic fibers. Conclusions. Lipid and DNA oxidative stress were present in the conjunctiva. Increased tear inflammation seemed to coexist with loss of conjunctival epithelial cohesiveness and increased collagenolytic activity, which may explain the conjunctival laxity observed in patients with conjunctivochalasis.

Elastic fiber staining and cytokeratin 15 expression pattern in trichoepithelioma and basal cell carcinoma

Trichoepithelioma (TE) is a benign neoplasm of the skin that resembles basal cell carcinoma (BCC) in its clinical and histological features. In this study, we evaluate the usefulness of elastic fiber staining and cytokeratin 15 expression pattern in terms of distinguishing TE from BCC. Eleven TE and 17 BCC were examined histochemically and immunohistochemically. It was found that BCC contain more elastic fiber than TE, and that more TE show peripheral localization than BCC in cytokeratin 15 expression patterns. The present study shows that elastic fiber staining and cytokeratin 15 expression pattern may aid the differentiation of TE from BCC.

The expression and effect of elastin in full-term rats with hyperoxia induced by chronic lung diseases

Objective To investigate the expression and effect of elastin in full-term rats with hyperoxia induced by chronic lung diseases. Methods One hundred and forty-four full-term rats are randomly exposed to hyperoxia (hyperoxia group)and room air(room air group).Chronic lung disease(CLD)is induced by hyperoxia exposure. Gomori's stain for elastic fibers and in situ hybridization methods were used to detect the expressions of secondary crest and tropoelastin mRNA on the 1st,3 rd, 7th, 10th,14th and 21st days after exposure. Results The expressions of secondary crest decreased significantly in hyperoxia group, compared with room air group on the 3rd to 14th days(P＜0.05).The expressions of tropoelastin mRNA decreased significantly in hypemxia group, compared with room air group on the 3rd to 10th days (P＜0.05),otherwise increased significantly from the 14th to 21 st days(P＜0.05). Hyperoxia exposure can delay the peak of tropoelastin mRNA. Conclusion Elastin is involved in the inhibition of alveolarization and lung fibrosis in the development of CLD. Key words: Elastin; Oxygen/AE; Lung diseases

Platelet and endothelial cell-derived microparticles in steroid-induced osteonecrosis of the femoral head of rabbit model

To explore the relationship between the alterations of platelet-derived microparticles (PMPs) and endothelial cell-derived microparticles (EMPs) and steroid-induced osteonecrosis of the femoral head. Forty-four adult Japanese white rabbits were randomly divided into 2 groups: experimental group (n = 44), injected intramuscularly once with 20 mg/kg of methylprednisolone acetate, and control group (n = 28) injected with normal saline of the same dose. Blood samples were collected from the auricular vein while the animals were in a fasting state in early morning prior to experiment (week 0), and 2, 4, and 8 weeks after the injection. The levels of prothrombin time (PT), activated partial prothrombin time (APTT), and anti-thrombokinase-III (AT-III) were examined. Plasma was ultra-centrifuged and the circulating platelet and EMPs were isolated to undergo flow cytometry to detect the amounts of CD31, CD42a, CD54, and CD62E. 1, 2, 4, and 8 week after the injection 6 rabbits from the experimental group and 4 rabbits from the control group were sacrificed respectively and their femoral heads were taken out to undergo histopathologic examination with HE staining and microthrombus and elastic fiber staining. The PT, APTT, and AT-III levels increased significantly 1 to 8 weeks after the injection. The numbers of EMPs and PMPs were also increased markedly after steroid administration. Histopathologic examination demonstrated an accumulation of bone marrow cell debris, presence bone empty lacunae in the trabeculae 1 week after the steroid injection. 2, 4, and 8 weeks after the steroid injection the bone necrosis was remarkable, fatty degeneration of bone marrow cells occurred, the diameter of fat cells increased, and the area ratio of fatty cells became higher. MSB staining was positive. High dose glucocorticosteroid increases the levels of PMPs and EMPs that may be related to hypercoagulability and thrombosis in microcirculation and play an important role in steroid-induced osteonecrosis. MP can be considered a true target in the pharmacological control of steroid-induced osteonecrosis.

Idiopathic and Collagen Vascular Disease Nonspecific Interstitial Pneumonia: Clinical Significance of Remodeling Process

Recently, active remodeling may indicate a good prognosis in idiopathic interstitial pneumonias. In this study we sought to validate the importance of the collagen/elastic system in the extracellular matrix remodeling and to study the relationships between the collagen/elastic system in nonspecific interstitial idiopathic pneumonia (NSIP) and collagen vascular disease associated with nonspecific interstitial idiopathic pneumonia (CVD-NSIP). We examined collagen/elastic system fibers in open lung biopsies of 20 idiopathic NSIP and 21 CVD-NSIP patients. The clinical features were analyzed with respect to age, gender, pulmonary functional tests, chest X-ray and computed tomography, treatment, and survival. We used the picrosirius polarization method and Weigert's resorcin-fuchsin histochemistry and morphometric analysis to evaluate the amount of collagen/elastic system fibers and their association with the NSIP histologic pattern. No differences in clinical features and pulmonary function tests were observed between idiopathic NSIP and CVD-NSIP, but a significantly higher collagen and elastic fiber proliferation was detected in CVD-NSIP lungs and fibrosing NSIP histologic pattern. Multivariate Cox model analysis demonstrated that sex and quantitative elastic fiber staining added important prognostic information (p=0.01) and was indicative of a worse prognosis than collagen staining. A cut point at the mean staining of 1.5% for elastic fibers divided the patients into two groups with distinctive survival times. Those with elastic fibers greater than 1.5% had a median survival time of just 52 months. We concluded that idiopathic NSIP and CVD-NSIP were clinically similar but pathologically different, suggesting that different remodeling profiles in NSIP may represent evolutionary adapted responses to injury grade, which depend, at least in part, on the extent of elastic extracellular matrix deposition. Patients with greater than 1.5% of elastic fibers comprise a subset with a high risk for dying due to NSIP and may be an appropriate target for prospective studies.

In vivo imaging of elastic fibers using sulforhodamine B

Until now, the imaging of elastic fibers was restricted to tissue sections using the endofluorescence properties of elastin or histological dyes. Methods to study their morphology in vivo and in situ have been lacking. We present and characterize a new application of a fluorescent dye for two-photon microscopy: sulforhodamine B (SRB), which is shown to specifically stain elastic fibers in vivo. SRB staining of elastic fibers is demonstrated to be better than using elastin endofluorescence for two-photon microscopy. Our imaging method of elastic fibers is shown to be suitable for simultaneous imaging with both other fluorescent intravital dyes and second-harmonic generation (SHG). We illustrate these findings with intravital imaging of elastic and collagen fibers in muscle epimysium and endomysium and in blood vessel walls. We expect SRB staining to become a key method to study elastic fibers in vivo.

Quantitative analysis of the elastic fibres in the human temporomandibular articular disc and its attachments

A quantitative study of the elastic fibres found in the human temporomandibular disc and its attachments was performed. Seven left discs from 57- to 82-year-old subjects, without macroscopic evidence of a TMJ disorder, were analysed and prepared in parasagittal sections. The surface amount was measured, thresholded and expressed from 0 to 1, using microscopic digitized views after Weigert's resorcin–fuchsin staining of elastic fibres. Fibre density rates ranged from 0 to 0.687. The mean density was 0.1532 ( σ = 0.1150) in the upper bilaminary zone, 0.1097 ( σ = 0.1159) in the lower bilaminary zone, 0.0474 ( σ = 0.0782) in the anterior band, 0.0180 ( σ = 0.0603) in the posterior band and null in the intermediate zone. The difference in density rate between the structures was significant, except for the posterior band and the intermediate zone. The elastic fibre density rates in central and medial locations of the upper and lower bilaminary zones were twice as big as in the lateral locations. In the anterior band, the elastic fibre density was less abundant medially than in its lateral part. These quantitative results support the current elastic fibre distribution scheme, and confirm the necessity of studying their orientation, taking into account age and temporomandibular joint health parameters.

Lysyl Oxidase Is Essential for Normal Development and Function of the Respiratory System and for the Integrity of Elastic and Collagen Fibers in Various Tissues

Lysyl oxidases, a family comprising LOX and four LOX-like enzymes, catalyze crosslinking of elastin and collagens. Mouse Lox was recently shown to be crucial for development of the cardiovascular system because null mice died perinatally of aortic aneurysms and cardiovascular dysfunction. We show here that Lox is also essential for development of the respiratory system and the integrity of elastic and collagen fibers in the lungs and skin. The lungs of E18.5 Lox(-/-) embryos showed impaired development of the distal and proximal airways. Elastic fibers in E18.5 Lox(-/-) lungs were markedly less intensely stained and more disperse than in the wild type, especially in the mesenchyme surrounding the distal airways, bronchioles, bronchi, and trachea, and were fragmented in pulmonary arterial walls. The organization of individual collagen fibers into tight bundles was likewise abnormal. Similar elastic and collagen fiber abnormalities were seen in the skin. Lysyl oxidase activity in cultured Lox(-/-) skin fibroblasts and aortic smooth muscle cells was reduced by approximately 80%, indicating that Lox is the main isoenzyme in these cells. LOX abnormalities may thus be critical for the pathogenesis of several common diseases, including pulmonary, skin, and cardiovascular disorders.

Penile enhancement using a porcine small intestinal submucosa graft in a rat model

Several biodegradable materials have been experimented for penile enhancement, but none show the potential for clinical use. This study was designed to use porcine small intestinal submucosa (SIS) augmenting the normal tunica albuginea to increase the functional girth of the rat penis. In all, 20 adult male Sprague-Dawley rats constituted the study population. The animals were divided into two groups: group 1 consisted of the control (n=10) and group 2 (n=10) consisted of rats that underwent penile enhancement by a longitudinal I-shaped incision of the tunica albuginea on both sides, and the dissection of the plane between tunica albuginea and cavernosal tissue was carried out (n=10). The incision was then patched with a 3 x 10 mm2 piece of SIS, using a 6/0 nylon suture material. The penile length and mid-circumference were then measured using a Vernier Caliper before and 2 months after surgery. All rat penises underwent histological examination using Masson's trichome and Verhoff's van Giesen's stain for collagen and elastic fibers. The penile length, mid-circumference and degree of fibrosis score were expressed as mean+/-s.e. (standard error) and analyzed using a Wilcoxon rank-sum test. A statistical significance was accepted at P-value < or =0.05. Our results showed similar preoperative penile length and circumference in both groups. However, 2 months after the surgery, the mean penile circumference of the SIS group has grown significantly larger than the control group, while the mean penile length remained unchanged. The histological study of the rat penises revealed minimal amounts of fibrosis under the graft, and the elastic fibers of the graft showed orientation in a circular manner. In conclusion, SIS appears promising for material use in a penile enhancement.

Acid‐Orcein Giemsa: A Multifunctional Stain

The hematoxylin and eosin (H&amp;E) stain is the most common method used worldwide for routine pathologic evaluation of tissue specimens. Evaluation of cutaneous specimens frequently requires differentiation of elastic fibers, melanin, hemosiderin, fungal elements, mast cells and depositions. For this reason, we used acid‐orcein and Giemsa (AOG) stain to evaluate various skin disorders to determine the extent of utility of this infrequently reported stain. As expected, AOG stain functioned well as an elastic fiber stain, highlighting loss of elastic fibers in areas of scar and in disorders such as anetoderma. In pigmentary disorders, AOG stains melanin a dark green to greenish‐black pigment while hemosiderin remained yellow‐brown to light green color. Fungal hyphae in superficial dermatophytosis and leishmania organisms stained a deep blue. Amyloid stained a “sky” blue color in macular, lichenoid and nodular amyloid cases. The granules of mast cells stain purple in cases of urticaria pigmentosa and mastocytomas. Dermal mucin stained metachromatic lavender. Due to the multifunctional nature of the AOG stain, this simple technique can improve dermatopathologic diagnosis while decreasing the number of special stains necessary to have available in the laboratory setting.

Paper 17: Regulation of Lysyl Oxidase in the Vaginal Wall: Role of Estrogen, Progesterone, and Pregnancy

OBJECTIVES: Lysyl oxidases are copper-dependent amine oxidases produced by activated smooth muscle cells and fibroblasts. Mammals have up to five potential LOX family members (lysyl oxidase (LOX), and lysyl oxidase-like (LOXL) proteins 1 through 4). These enzymes play a vital role in the extracellular cross-linking and stabilization of collagen and elastin both in development and in response to injury. Recently, it was reported that LOXL1 knockout mice develop pelvic organ prolapse. The goal of this investigation was to determine the regulation of LOX and LOXL1 in vaginal tissues from nonpregnant and pregnant mice and correlate these changes with remodeling of the vaginal extracellular matrix (ECM) during pregnancy. METHODS: Real-time PCR was used to quantify mRNA for LOX and LOXL1 in vaginal tissues from ovariectomized, nonpregnant, pregnant, parturient, and postpartum mice (n=4–8 at each time point). Messenger RNA levels were expressed relative to β-2 microglobulin. To determine the hormonal regulation of LOX in the vagina, mice were ovariectomized and treated with vehicle, 17β-estradiol (E2, 50 μg/kg), progesterone (P, 1 mg/d), or E2+P for 3 days. In paired animals, Masson's trichrome and elastic fiber staining was performed. RESULTS: Early in pregnancy (d8-10), expression of LOX decreased 8- to 10-fold in the vagina, and remained suppressed throughout gestation. LOX mRNA, but not LOXL1, in the vagina increased significantly in labor and 12–36 hours postpartum. Changes in LOX mRNA were accompanied by matrix remodeling in the vaginal wall. While the matrix of the vaginal wall in nonpregnant mice was characterized by dense well-organized collagen bundles and numerous elastic fibers suspending the muscularis to the basal lamina of the vaginal epithelium, the intensity of collagen staining progressively decreased during pregnancy. Decreased collagen density, increased interstitial edema, and dissolution of the ECM were maximal 2–6 hours after delivery. Reorganization of the matrix occurred by 48 hours postpartum. Expression of LOX was decreased 25-fold in vagina from ovariectomized compared with nonpregnant cycling mice. E2 treatment resulted in significant increases in LOX mRNA (0.04 ± 0.01 to 0.61 ± 0.12, P≤0.01), whereas progesterone inhibited estrogen-induced increases in LOX mRNA (0.33 ± 0.15). CONCLUSIONS: The vaginal muscularis undergoes dynamic changes during pregnancy characterized by remodeling of the ECM and decreased expression of lysyl oxidase. Estrogen may regulate cross-linking of collagen and elastin in the vaginal muscularis through increased transcription of LOX. On the other hand, suppression of LOX by high levels of progesterone during pregnancy or by low levels of estrogen after menopause may contribute to decreased formation of collagen and elastin in the extracellular matrix of the vagina.

Histological Study of the Normal Vertebral Artery-Etiology of Dissecting Aneurysms-

Histological evaluation of dissecting aneurysms of the cerebral arteries has suggested that defects in the internal elastic lamina (IEL) induce dissection of the arterial wall. Dissecting aneurysms occur most frequently in the vertebral artery (VA). The present study examined sections of the normal VA to elucidate the mechanisms of arterial dissection. Bilateral VAs (20 vessels) were obtained from 10 patients who died of causes other than intracranial lesions. The VAs were detached from the VA union to the site 10 mm proximal from the point penetrating the dura mater. The VAs were cut at 5-mm intervals, and each segment was observed using modified Masson's trichrome staining for elastic fibers. The thickness of the media and adventitia significantly thinned after the origin of the posterior inferior cerebellar artery (PICA). IEL defects were observed at 35 sites in 11 vessels from six subjects. There was a high incidence of IEL defects in the extradural portion and near the origin of the PICA, areas frequently involved in arterial dissection. There was a high incidence of intimal thinning at areas of IEL defects (19 of 35), and thinning was particularly marked distal to the origin of the PICA. In the absence of intimal thickening, the vascular strength at the site of IEL defects may be reduced, which would promote the occurrence and progression of arterial dissection.

Carmine-picroindigocarmine: An alternative multiple staining method

Carmine-picroindigocarmine, a multiple staining method, was developed at the beginning of the previous century by Professor Harry Kull at the University of Tartu. The stain, combining copper carmine, picric acid and indigocarmine gives bright and colourful results. Nuclear structures are stained in red, cytoplasm in varying shades from yellow to green, collagen fibres in blue, the matrix of hyaline cartilage in greyish-blue, muscle tissues from brownish-red to brownish-green, erythrocytes in yellow. Squamous epithelia are stained in red with horney layers in dark red, nail plate and hairs are stained in bright yellow. The carmine-picroindigocarmine staining is stable, which allows for the combining of additional dyes without interfering with the main colouring. The combination of carmine-picroindigocarmine staining with resorcin-fuchsine in principle maintained the colouring of Kull's original method with additional staining of elastic fibres in violet colour that clearly differentiated them from blue stained collagen fibres. The described multiple staining gives an original colourful and aesthetic result, providing an alternative to other multiple staining methods.

A contribution to the theory of biological staining based on the principles for structural organization of biological macromolecules

Biological staining is to a large degree explainable based on the principles governing folding and aggregation of macromolecules in aqueous solution. Most macromolecules are polyions, which, except for heteropolysaccharides, have a large proportion of nonpolar or only slightly polar residues. Because they are amphiphilic, they react in water by a complex set of hydrophobic interactions involving charged residues, nonpolar residues and water molecules. The hydrophobic interactions lead to complex folding systems or micelle-like structures. Dyes are amphiphilic molecules with a tendency to form micelles, but with limitations due to geometric constraints and charge repulsion. Macromolecules and dyes react with each other in aqueous solution following the same principles as for the structural organization of macromolecules, as in protein folding for example. Dye binding requires near contact between nonpolar groups in both the dye and macromolecule, and this is accomplished by choosing a pH at which the dye and macromolecule have opposite net charges. Charge attraction is insufficient for binding in most cases, but it is directive because it determines which macromolecules a given dye ion is able to contact. These considerations apply to the staining of globular (cytoplasmic) proteins and to nucleic acid staining. The staining mechanism is by hydrophobic interactions. Above approximately pH 3.5, DNA may also bind dyes by hydrophobic intercalation between the bases of the double helix; at lower pH the double helix opens and dye binding is as for RNA and globular proteins. Heteroglycans (mucins) have virtually no nonpolar groups, so nonpolar interactions are restricted to the dye molecules. Metachromatic staining of heteroglycans is due to hydrophobic bonding or micelle formation between the monovalent planar dye molecules aided by charge neutralization by the negatively charged heteroglycans. Alternatively, as the charge attraction increases with the number of closely placed charges, acidic heteroglycans may be stained by a polycation such as alcian blue or colloidal iron. For elastic fiber and collagen staining, actual hydrophobic interactions are less important and hydrogen bonding and simple nonpolar interactions play a major role. These macromolecules may therefore be stained using a nonaqueous alcoholic solution.

Pulmonary vascular sclerosis in an albino rat with leukemia

The animal investigated was a two years old male control Sprague-Dawley rat which died spontaneously during a carcinogenicity study. Post-mortem examination disclosed hepatic and splenic enlargement. At microscopical examination, massive leucaemic infiltration was observed in many tissues/organs, including bone marrow, spleen, liver and renal blood vessels. A very unusual finding was observed in the lung, consisting of scattered micronodules which replaced most of the lung parenchyma. They contained collagen, displaying a somewhat circular distribution at the periphery of the lesions, fibrin, leukemic cells and fibroblasts. Immunostaining for desmin revealed the presence of smooth muscle fibers within the nodules, while staining for elastic fibers showed clearly that the internal and external elastic membranes were identifiable within the nodules. The diagnosis of pulmonary vascular sclerosis was made on the basis of microscopical and immunohistochemical findings.

Angiogenesis inhibitor endostatin is a distinct component of elastic fibers in vessel walls.

Theendothelial cell inhibitor endostatin (22 kDa) is part of the carboxyl-terminal globular domain of collagen XVIII and shows a widespread tissue distribution. Immunohistology of adult mouse tissues demonstrated a preferred localization in many vessel walls and some other basement membrane zones. A strong immunogold staining was observed across elastic fibers in the multiple elastic membranes of aorta and other large arteries. Staining was less strong along sparse elastic fibers of veins and almost none was observed in the walls of arterioles and capillaries. Strong evidence was also obtained for some intracellular and basement membrane associations. Immunogold double staining of elastic fibers showed a close colocalization of endostatin with fibulin-2, fibulin-1, and nidogen-2, but not with perlecan. Reasonable amounts of endostatin could be extracted from aorta and skin by EDTA, followed by detergents, with aorta being the richest source of the inhibitor identified so far. Solubilizations with collagenase and elastase were approximately fivefold less efficient. Immunoblots of aortic extracts detected major endostatin components of 22-25 kDa whereas skin extracts also contained some larger components. Solid-phase assays demonstrated distinct binding of recombinant mouse endostatin to the fibulins and nidogen-2, consistent with their tissue colocalization. Together, the data indicate several different ways for endostatin to be associated with the extracellular matrix, and its release may determine biological activation. This also defines a novel function for some elastic tissues.

弾性線維腫の１例

Cytological findings of a case of elastofibroma dorsi are described. A 58-year-old female presented with a slowgrowing mass in the left subscapular region. The excised lesion measuring 6×4×3cm was an ill-defined white elastic mass. Scraping cytological specimens showed benign-appearing spindle cells and light-green stained, bead string-like or globular structures, which were intensely stained with elastic fiber staining. Ultrastructurally, the structures were composed of electron-dense materials with cores of thin filaments. The spindle cells showed fibroblastic differentiation with intermediate filaments.Immunohistochemically, the cells were positive for vimentin, α-smooth muscle actin and desmin, indicating mvnfihrnhlastir or fibroblastic differentiation.

Elastic reinforcement and thickness of the joint capsules of the lower cervical spine.

Mechanical studies have shown the major strength of the joint capsules of the lower cervical spine, especially in its ventrolateral part. The aim of this study was to examine the structure of the joint capsules in order to discover if there is a correspondence between biomechanical properties and descriptive anatomy. Ten transverse sections and 4 sagittal sections obtained from 6 cadavers were observed under light microscopy at X 25 to X 250 magnification. Standard stains and specific elastic fiber stain were used for histologic preparation. The data were the thickness of the joint capsules in the different quadrants, and the topography and direction of the elastic fibers. The results showed that the ventrolateral part of the joint capsules is thick and reinforced by oblique elastic fibers. The dorsal part is thin. The authors suggest that the descriptive anatomy of the joint capsules confirms their mechanical properties. They note that the role of the ventrolateral part is supplemented by that of the posterior longitudinal ligament for the stability of the functional cervical spinal unit.