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PubMed1988

Early and late surfactant treatments in baboon model of hyaline membrane disease.

Because the issue of optimal time for artificial surfactant therapy for hyaline membrane disease has not been established, the effects of treatment with a reconstituted bovine surfactant (surfactant TA) were compared at two time periods in a hyaline membrane disease model in a premature baboon. The baboons were delivered by cesarean section at 75% of gestation (139.5 +/- 1.5 days, mean +/- SD). One group was treated with surfactant TA within ten minutes after birth (ultraearly), another group was treated at two hours of age (late) and a third (comparison group) did not receive the surfactant. Both treatment groups had significantly higher compliance and ratio of arterial to alveolar Po2 ratio and lower mean airway pressure and oxygen requirement (Fio2) than the comparison group. At autopsy, the largest residual volume and hysteresis in pulmonary pressure-volume curves were noted in the ultraearly group, intermediate values were found in the late group, and least values were found in the comparison group. These data indicate that early surfactant therapy for hyaline membrane disease results in greater improvement in lung mechanics than delaying treatment, even for two hours. Delivery room treatment with surfactant of infants at risk for hyaline membrane disease is perhaps better than therapy for established hyaline membrane disease.

Animals↗
PubMed1987

Absence of tubular myelin in lungs of infants dying with hyaline membrane disease.

Immaturity of the pulmonary surface active material synthesizing system with deficiency of surface active material in the premature lung is an accepted cause of hyaline membrane disease. Lamellar bodies, the intracellular form of surface active material, are produced and secreted from Type II pneumocytes and converted to tubular myelin in the alveolar lumen. Tubular myelin, in turn, gives rise to the surface monolayer, which has the greatest surface active property. Thus, lung sections were studied by light and electron microscopy from 35 infants who died of histologically confirmed hyaline membrane disease and 19 infants who died of other causes. Tubular myelin was not identified ultrastructurally in lungs of infants who died of hyaline membrane disease, despite the presence of abundant lamellar bodies. In contrast, 16 of 19 infants dying of other causes had easily identifiable tubular myelin in addition to lamellar bodies. The absence of tubular myelin in the hyaline membrane disease patients suggests an abnormality in the conversion of lamellar bodies to tubular myelin. The authors speculate that this abnormal lamellar body turnover may be important in the pathogenesis of hyaline membrane disease.

Freeze Fracturing↗
PubMed1984

Cytoplasmic filaments of Crooke's hyaline change belong to the cytokeratin class. An immunocytochemical and ultrastructural study.

Crooke's hyaline change was studied by immunocytochemistry using an anti-adrenocorticotropic hormone (ACTH) antiserum and five different antisera against cytokeratins. Crooke's hyaline appears in basophil cells of the adenohypophysis in patients with hypercortisolism, presumably as a part of the negative feedback on corticotropin secretion. Previous studies have identified the hyaline material as a simple protein, apparently unrelated to ACTH, and electron microscopy has revealed a loss of secretory granules and an accumulation of 6-9-nm filaments in the cytoplasm of affected cells. In this study, the secretory granules in adenohypophysial cells exhibiting Crooke's hyaline change were labeled by anti-ACTH antibodies, while the hyaline material was positive for cytokeratin with each of the five antisera used. The results suggest that high levels of glucocorticoids may stimulate elaboration of cytokeratins in basophils while they suppress the production and release of ACTH.

Adenoma, Basophil↗
PubMed1980

Pulmonary yellow hyaline membranes in neonates.

The recent increase in the occurrence of pulmonary yellow hyaline membranes correlates with improved therapy for premature infants with the respiratory distress syndrome and with their prolonged survival. We compared the clinicopathologic features in 54 cases with pulmonary yellow hyaline membranes with those in 56 cases with conventional hyaline membranes seen during the same interval at Magee-Womens Hospital. Kernicterus, intraventricular hemorrhage, intrahepatic bile stasis, pulmonary hemorrhages, and disseminated intravascular coagulation were significantly frequent in the yellow hyaline membrane group. Clinical problems of hypoglycemia, hypocalcemia, jaundice, and endotracheal hemorrhages and also treatment with endotracheal intubation, ventilatory assistance, and phototherapy were much more common in the yellow hyaline membrane cases. The yellow pigment was identified as unconjugated bilirubin by histochemical and biochemical techniques. A plausible hypothesis for the pathogenesis is presented wherein intrapulmonary hemorrhages lay an important role. The frequent association of yellow membranes and kernicterus in premature infants at relatively low serum levels of bilirubin is significant.

Birth Weight↗
PubMed1978

[Morphological variants of alcoholic hyalin and possible ways of its evolution].

Possible ways of alcohol hyalin evolution were studied by repeated electron microscopic examinations of the livers of 2 patients with acute alcoholic hepatitis Four types of ultrastructure of alcoholic hyalin were found: parallely oriented fibrillae, randomly oriented fibrillae, fine granular and large granular (spotlike) substance. Examinations of the material from repeated biopsies showed fibrillar hyalin to be "young" and to turn into "old" hyalin of granular structure. The evolution of alcoholic hyalin from fibrillar to granular is accompanied by hepatocyte necrosis and leukotaxic effect.

Adult↗
PubMed1979

[Nature and origin of hepatocellular hyaline, Mallory bodies].

The current concepts on the nature and origin of alcohol hyaline are analysed. The latter is a sign of acute alcoholic hepatitis and reflects the severity of destructive and inflammatory processes in the organ; it is based on the protein-polysaccharide-phospholipid complex which has three ultrastructural varieties. The pathogenesis of alcohol hyaline is complex. In addition to the metabolic and toxic effect of ethanol, it includes the following stages: (1) inhibition of dissemination of intermediate filaments synthesized by rough reticulum; (2) accumulation of filaments in cisternae of the rough endoplasmic reticulum and formation of fibrillar hyaline; (3) transformation of the fibrillar hyaline into granular one; (4) hepatocyte necrosis. Alcoholic hyaline as an autoantigen induces antibody production followed by the involvement of the immunopathological mechanisms.

Autoantigens↗
PubMed1992

Contractile proteins in the hyaline cells of the chicken cochlea.

Hyaline cells are a single layer of epithelial cells found at the inferior edge of the sensory epithelium in the chick cochlea. They rest directly above a specialized region of the basilar membrane at a point where it connects to the fibrocartilaginous skeleton of the cochlear duct. The basal cytoplasm of the hyaline cells contains a bundle of linearly aligned actin filaments that resemble stress fibers in their organization. The actin filaments are anchored in the basal plasma membranes of the cells, which are, in turn, associated with the underlying basal lamina and the extracellular matrix of the basilar membrane. We have used a combination of transmission electron microscopy, differential-interference-contrast and epifluorescence light microscopy, and confocal laser scanning microscopy to study the composition and organization of these actin bundles within the hyaline cells. The bundles are arranged into triangular wedges that are oriented radially across the basilar membrane. Each cell contains one or two actin wedges. Adjacent cells can have them aligned in opposite directions so that in a whole-mount surface preparation they appear as interdigitations. Immunofluorescent staining of the hyaline cells has shown that smooth muscle myosin and alpha-actinin are co-localized to the actin bundles. Smooth muscle myosin is also found throughout the cytoplasm of the cells. The fact that hyaline cells in the chick cochlea are contacted by efferent nerve fibers suggests that these cells may regulate tension on the basilar membrane via the specialized bundle of actin filaments.

Animals↗
PubMed1990

The potential of adult human perichondrium to form hyalin cartilage in vitro.

The usefulness of adult human perichondrium for the restoration of articular cartilage defects depends on the potential to form hyalin cartilage. In order to evaluate the capacity of adult human perichondrium to form hyalin cartilage in vitro, perichondrium of the rib of eight adult human beings was cultured in vitro. After removal of residual cartilage, perichondrial explants were cultured for 7 or 10 days. The explants were histologically examined using specific stains to prove the presence of glycosaminoglycans (GAGs) normal for hyalin cartilage. Clear differentiation of perichondrial cells towards chondrocytes was noted. The chondrocytes synthesized new matrix substances normally present in hyalin cartilage. This investigation supports the usefulness of adult human rib perichondrium for the restoration of cartilage defects. Due to the enormous potential of the rib perichondrium to form hyalin cartilage in vitro, even defects in joints with a rather thick cartilage layer might be restored using this biological material.

Adult↗
PubMed1994

Conversion to an elastogenic phenotype by fetal hyaline chondrocytes is accompanied by altered expression of elastin-related macromolecules.

Elastic fibers are produced during fetal and neonatal periods, and by maturity elastin expression has ceased. Fetal bovine hyaline chondrocytes acquired an elastogenic phenotype within 24 hr after isolation from the tissue, even though the tissue does not produce elastic fibers or tropoelastin mRNA in vivo. By multiple parameters, hyaline chondrocytes produced elastic fibers that were indistinguishable from those made by elastic chondrocytes derived from fetal elastic ear cartilage. The levels of tropoelastin mRNA, secreted protein, and elastic fiber crosslinks as well as the immunostaining and ultrastructural appearance of elastic fibers produced by cultured hyaline chondrocytes were similar if not identical to those of cultured elastic chondrocytes. We also examined the expression of elastin-associated microfibrillar proteins. In intact hyaline cartilage, we did not detect mRNA for fibrillin 5 mRNA and saw only a relatively weak signal for fibrillin 15 mRNA. These microfibrillar products were expressed with tropoelastin in cultured hyaline chondrocytes as well as in intact elastic cartilage and cultured elastic chondrocytes, suggesting that fibrillin 5 and fibrillin 15 are required for elastic fiber formation. In contrast, the levels of microfibrillar-associated glycoprotein mRNA were decreased in both cell types relative to the high expression seen in vivo. These data indicate that conversion to the elastin phenotype includes induction or modulation of all known components of elastic fibers.

Animals↗
PubMed1989

Hyaline-cell cartilage (chondroid) in the heads of teleosts.

The structure and distribution of hyaline-cell cartilage (chondroid) (HCC) in the heads of teleosts has been studied in 48 species from 16 families. The tissue is pale-staining and has closely-packed, hyaline cells that are separated by a small quantity of matrix. The matrix has only a mild affinity for alcian blue and the cells are not shrunken within lacunae. Two subtypes of the tissue are here described--fibrohyaline-cell cartilage (chondroid) where collagen fibres are prominent in the matrix, and lipohyaline-cell cartilage where fat and hyaline cells are intermingled. An elastic hyaline-cell cartilage has been described previously. Associations of HCC with dense fibrous connective tissue, mucochondroid, hyaline cartilage and bone are described. Lists are provided of membrane and cartilages bones to which the tissue is attached and of species in which it is common. Suitable 'type examples' for reference and for further study include the cartilage in the rostral folds of the red-tailed black shark, Labeo bicolor and the flying fox, Epalzeorhynchus kalopterus. HCC occurs in lips and rostral folds, in pre-palatine and submaxillary menisci, in ligaments, at the anterior end of the basihyal, in the pectoral girdle, in adhesive discs, in gill arches, beneath the basioccipital chewing pad, in barbels, next to the facial nerve, around the olfactory region and in the core of the nasal skin flaps. It is a particularly important tissue in cyprinids and related fish, and enormous masses of it are present in the black shark, Morulius chrysophekadion and the Hong Kong pleco, Pseudogastromyzon myersi. It acts as a damper against the contractions of the heart or the pressure of occluding pharyngeal teeth, and it provides the mouth region of bottom-dwelling, algal eaters with flexible support. In relation to Schaffer's classification of supporting tissues, I confirm a distinction between HCC and Zellknorpel.

Animals↗
PubMed1991

The role of lysosomes in hyaline droplet nephropathy induced by a variety of pharmacological agents in the male rat.

The male rat is prone to hyaline droplet formation in renal proximal tubular cells. Several unrelated pharmaceutical agents exacerbate the formation and accumulation of these droplets. Where the loading of the proximal tubular cells is marked it gives rise to increased cell turnover and a hyaline droplet nephropathy develops. Cytochemical procedures, have confirmed that this accumulation of hyaline droplets represents an increase in the size and number of secondary lysosomes involved in protein uptake and metabolism. This predisposition of the male rat to develop hyaline droplet nephropathy relates to (1) the large amounts of the low-molecular-weight protein alpha 2U globulin in the glomerular filtrate, (2) the resistance of the globulin to proteolysis, and (3) the low protease activity in the proximal tubule lysosomes. The current data would suggest that the pharmacological agents, which cause the nephropathy, exert their effect by reducing the proteolytic breakdown of alpha 2U globulin in the proximal tubule lysosomes. This results in the overloading of a system which is already operating near maximal load. Female rats, and all other species excrete only small amounts of alpha 2U globulin or similar proteins, which are more easily hydrolyzed. Thus it is argued that the type of hyaline droplet nephropathy induced by these pharmacological agents is unique to the male rat and of little relevance to man.

Animals↗
PubMed1990

A hyaline layer protein that becomes localized to the oral ectoderm and foregut of sea urchin embryos.

An antigen is described which is a marker for the oral ectoderm and foregut of the sea urchin embryo. In Lytechinus variegatus, the antigen is first detectable by immunofluorescence on the surface of fertilized eggs, and remains globally distributed through the early stages of gastrulation. Thereafter the antigen is localized to the oral ectoderm and foregut, coincident with the morphogenesis of these regions. The antigen is a large, detergent-insoluble, filamentous glycoprotein associated with the tips of the microvilli in the hyaline layer. This glycoprotein is present in two forms, a approximately 350-kDa form that is maternally synthesized and a much larger form which is synthesized at late gastrula stage as a 350-kDa precursor before becoming modified and assembled into the hyaline layer. The timing of synthesis of the zygotic form of the molecule correlates precisely with the localized expression of the antigen. The antigen copurifies with intact hyaline layers and cosediments with hyalin in the presence of calcium, suggesting that it is a structural component of the hyaline layer.

Animals↗
PubMed1997

Expression of stratified epithelial-type cytokeratins in hyalinizing trabecular adenomas supports their relationship with papillary carcinomas of the thyroid.

AIM: To evaluate the cytokeratin pattern of expression of hyalinizing trabecular adenomas and to verify whether or not these tumours, that share morphological features with papillary carcinomas, present the stratified epithelial-type cytokeratins commonly found in ordinary papillary carcinomas. METHODS AND RESULTS: This study consisted of the immunohistochemical detection of simple and stratified epithelial type cytokeratin filaments in a series of six hyalinizing trabecular adenomas, three papillary carcinomas with a trabecular growth pattern and two carcinomas combining hyalinizing trabecular and papillary patterns. Simple epithelial-type cytokeratins 7, 8, 18 and 19 were found in every case. Expression of the stratified epithelial-type cytokeratins 1, 5/6 and/or 13 was detected in four hyalinizing trabecular adenomas. CONCLUSION: Based on this, as well as on the cytological features and on the frequent co-occurrence of hyalinizing trabecular adenoma and papillary carcinoma, we suggest that the former lesion may be considered a peculiar encapsulated variant of papillary carcinoma.

Adenoma↗
PubMed1970

Direct isolation of the hyaline layer protein released from the cortical granules of the sea urchin egg at fertilization.

Treatment of the eggs of the sea urchin with a 1 M solution of glycerol at fertilization allows the recovery from this solution of the protein released from the cortical granules, including that which would normally give rise to the hyaline layer. The calcium-gelable protein previously extracted from whole eggs and from isolated cortical material was found to be present in the glycerol solution, confirming its localization in the cortical granules and its role in the hyaline layer. Quantitative measurements on the eggs of two Hawaiian species, Colobocentrotus atratus and Pseudoboletia indiana, which have the widest variation in the gel protein content, demonstrated that a proportionate amount of this material was released at fertilization in these species, which correlates with the thickness of the hyaline layer in the two cases. In addition, the calcium-insoluble fraction of Sakai can be extracted from these eggs after removal of the hyaline protein by glycerol, showing that this is a different material. A simple method for the separation of the hyaline protein from the calcium-insoluble fraction in solution is provided.

Animals↗
PubMedDate not supplied

Regeneration of hyaline articular cartilage with irradiated transforming growth factor beta1-producing fibroblasts.

The regeneration of hyaline articular cartilage by cell-mediated gene therapy using transforming growth factor beta(1) (TGF-beta(1))-producing fibroblasts (NIH 3T3-TGF-beta(1)) has been reported previously. In this study, we investigated whether TGF-beta(1)-producing fibroblasts irradiated with a lethal dose of radiation are still capable of inducing the regeneration of hyaline articular cartilage. NIH 3T3TGF-beta(1) fibroblasts were exposed to doses of 20, 40, or 80 Gy, using a irradiator, and then injected into artificially made partial defects on the femoral condyle of rabbit knee joints. The rabbits were killed 3 or 6 weeks postinjection and hyaline articular cartilage regeneration was evaluated by histological and immunohistochemical staining (n = 5 per each group). Irradiated NIH 3T3-TGFbeta(1) fibroblasts started to die rapidly 3 days after irradiation; moreover, the kinetics of their viability were similar regardless of the radiation intensity. TGF-beta1 expression, measured by ELISA, showed that the TGF-beta(1) protein produced from the irradiated cells peaked 5 days after irradiation and thereafter declined rapidly. Complete filling of the defect with reparative tissue occurred in all the groups, although variations were observed in terms of the nature of the repair tissue. Histological and immunohistochemical staining of the repair tissue showed that the tissue newly formed by irradiated NIH 3T3-TGF-beta(1) fibroblasts after exposure to 20 Gy had hyaline cartilage-like characteristics, as was observed in the nonirradiated controls. On the other hand, the repair tissue formed by NIH 3T3-TGF-beta(1) fibroblasts irradiated with 40 or 80 Gy showed more fibrous cartilage-like tissue. These results suggest that TGF-beta(1)-producing fibroblasts irradiated up to a certain level of lethal dose (i.e., 20 Gy) are able to induce normal-appearing articular cartilage in vivo. Therefore, irradiated heterologous cell-mediated TGF-beta(1) gene therapy may be clinically useful and an efficient method of regenerating hyaline articular cartilage.

3T3 Cells↗
PubMed1987

Extracellular hyaline bodies are basement membrane accumulations.

Diverse hyaline bodies occurring in various diseases were investigated immunocytochemically with antibodies to type IV collagen and laminin. These hyaline bodies included those found predominantly extracellularly in adenoid cystic carcinomas, endodermal sinus tumors, Spitz nevi, lichen planus, diabetic glomerular nodular sclerosis, and odontogenic cysts, and those found predominantly intracellularly in alcoholic liver disease, Kaposi's sarcoma, and malignant fibrous histiocytoma. The hyaline bodies found in the first six diseases displayed intense immunoreactivity for the basement membrane components, type IV collagen, and laminin, whereas the hyaline bodies occurring in the latter three diseases were unreactive. These findings suggest that a common histogenesis of the extracellular hyaline body is the stimulatory effect of an altered growth state (hyperplasia, neoplasia, or endocrinopathy) on basement membrane synthesis in cells that normally produce a basement membrane.

Basement Membrane↗
PubMed2005

Endometrioid carcinomas of the uterine corpus with sex cord-like formations, hyalinization, and other unusual morphologic features: a report of 31 cases of a neoplasm that may be confused with carcinosarcoma and other uterine neoplasms.

We describe a series of unusual endometrioid carcinomas (ECs) of the uterine corpus characterized in significant part by cords of epithelioid cells, spindle cells, and a hyalinized stroma that sometimes formed osteoid. These features, particularly when prominent, produced an appearance strikingly different from that of conventional EC, sometimes resulting in problems in differential diagnosis, especially with a malignant mullerian mixed tumor (carcinosarcoma). The 31 patients ranged in age from 25 to 83 years (mean, 52 years). The proportion within each stage were as follows: stage Ia, 9.7%, stage Ib, 45.2%, stage Ic, 9.7%, stage IIb, 16.1%, stage IIIc 3.2%, and stage IV, 3.2%. In 4 patients (12.9%), staging information was not available. On microscopic examination, typical EC, which accounted for 10% to 90% of the tumor, was admixed in 90% of cases with cords of epithelioid or spindle cells within a hyalinized stroma. In 3 cases, the tumor contained cords of cells without a hyalinized stroma. Areas with a diffuse growth of fusiform cells suggesting endometrial stromal cells were also occasionally seen in minor amounts. Seventy percent of the tumors exhibited squamous differentiation, and in 50% of the tumors there was a background of endometrial hyperplasia. Two thirds of the tumors were grade 2 and the remainder were grade 1. Vascular space invasion was identified in seven tumors. On immunohistochemical analysis, the typical EC component was strongly positive for keratin, whereas the keratin staining was more focal and variable in the epithelial cells in the cords. Muscle markers (desmin, actin), CD10, and inhibin were negative in the latter. Overexpression of p53 was found in only 1 case. Eighty-three percent of the patients were alive with no evidence of disease on follow-up (range, 2-115 months; mean, 34.4 months). The clinical features, including a typically low stage and generally good prognosis, and histologic findings are different from those of malignant mullerian mixed tumors that are characterized by both high-grade carcinomatous and sarcomatous components and an aggressive clinical course. Confusion with other neoplasms, particularly those with sex cord-like growth, such as uterine tumors resembling ovarian sex cord tumors and epithelioid smooth muscle tumors, may also arise. We refer to tumors with the features described herein as "corded and hyalinized endometrioid carcinomas," a designation that reflects their two most striking and consistent features. Corded and hyalinized endometrioid carcinomas are yet another example of the protean phenotype of endometrioid adenocarcinomas of the female genital tract that has been appreciated only in the last two decades.

Adult↗
PubMed2004

Hyalinizing Spitz nevus: spindle and epithelioid cell nevus with paucicellular collagenous stroma.

Hyalinizing spindle and epithelioid cell nevus (Spitz nevus) is an uncommon melanocytic lesion. The histologic features of this benign tumor can mimic those of certain benign (dermatofibroma and desmoplastic cellular blue nevus) and malignant (metastatic carcinoma and malignant melanoma) neoplasms. We report a woman with a hyalinizing Spitz nevus and review the clinical characteristics, histologic features, and differential diagnosis of this lesion. The lesion presented as an asymptomatic red firm nodule on her abdomen. Microscopic examination showed a symmetric lesion in the dermis. The neoplastic cells were large and epithelioid-shaped or plump and spindle-shaped. They were present as isolated individual cells, single cells in a linear pattern, small nests, and fascicles in a paucicellular hyalinized stroma. Neoplastic cells with prominent eosinophilic nucleoli were evenly exhibited from the superficial to deep lesion. Diffuse expression of S-100 protein and absence of staining with antibodies to cytokeratin and HMB-45 were observed. The features were diagnostic of a hyalinizing Spitz nevus. Hyalinizing Spitz nevus is a benign lesion whose histologic features may mimic dermatofibroma, desmoplastic cellular blue nevus, metastatic carcinoma, and malignant melanoma. Immunohistochemical studies are helpful to differentiate these lesions.

Abdomen↗