Dentin tubule orientation determines odontoblastic differentiation in vitro: A morphological study.

Odontoblasts are post-mitotic cells responsible for maintenance of the dentin, and are therefore important for dental health. In some cases, irreversible pulpitis leads to necrosis and consequently death of odontoblasts. Regenerative endodontics (RE) uses the concept of tissue engineering to restore the root canals to a healthy state, allowing for continued development of the root and surrounding tissue. Human dental pulp stem cells (hDPSCs) have been successfully used in RE to restore odontoblast function. Surface microgeometry is one of the most important factors involved in the induction of differentiation of hDPSCs into odontoblast-like cells. Although different authors have demonstrated the importance of a dentin-like surface with accessible dentin tubules to induce differentiation of hDPSCs, the ultrastructural characteristics of the cells and the secreted extracellular matrix have not been studied in depth. Here, we used an acellular dentin scaffold containing dentin tubules in different spatial geometries, which regulated their accessibility to cells. hDPSCs were cultured on the scaffolds for up to 6 weeks. Systematic characterization of differentiated cells was performed using both optical (hematoxylin and eosin, Masson trichrome, and immunohistochemical determination of dentin sialoprotein [DSSP]) and transmission electron microscopy. The results presented here indicated that cells grown on the dentin surface containing accessible dentin tubules developed a characteristic odontoblastic phenotype, with cellular processes similar to native odontoblasts. The cell organization and characteristics of secreted extracellular matrix were also similar to those of native dentin tissue. Cells grown on non-accessible dentin tubule surfaces secreted a more abundant and dense extracellular matrix, and developed a different phenotype consisting of secretory flat cells organized in layers. Cells grown far from the scaffold, i.e., directly on the culture well surface, developed a secretory phenotype probably influenced by biochemical factors released by the dentin scaffold or differentiated cells. The results presented here support the use of hDPSCs to regenerate dentin and show the utility of scaffold microgeometry for determining the differentiation and secretory phenotype of cultured cells.

Characterization of a new human cell line (CH-3573) derived from a grade II chondrosarcoma with matrix production.

Chondrosarcomas are malignant cartilage-forming tumors that represent the third most common malignant solid tumor of bone. In patients with grades II and III, local recurrence, increasing tumor size and dedifferentiation have been associated with lower survival rates. These biologically poorly-understood neoplasms vary considerably in clinical presentation and biological behavior. Cytogenetic studies have shown that heterogeneity is related to karyotypic complexity; moreover, alterations in the 9p21 locus and TP53 gene are related to disease progression. Despite the relatively high frequency of chondrosarcoma only a limited number of cell lines exist in the scientific community, limiting the possibility to study hypothesis-derived research or primary drug interaction necessary for pre-clinical studies. We report a chondrosarcoma cell line, CH-3573, derived from a primary tumor that may serve as a useful tool for both in vitro and in vivo models to study the molecular pathogenesis. In addition, xenograft passages in nude mice were studied to characterize the genetic stability over the course of tumor progression. In contrary to other reported cell lines, an important feature of our established cell line was the retained matrix production, a characteristic feature of a conventional grade II chondrosarcoma. The cell line (CH-3573) was characterized by pathological, immunohistochemical and molecular genetic methods.

Increased Goodpasture antigen-binding protein expression induces type IV collagen disorganization and deposit of immunoglobulin A in glomerular basement membrane.

Increased expression of Goodpasture antigen-binding protein (GPBP), a protein that binds and phosphorylates basement membrane collagen, has been associated with immune complex-mediated pathogenesis. However, recent reports have questioned this biological function and proposed that GPBP serves as a cytosolic ceramide transporter (CERT(L)). Thus, the role of GPBP in vivo remains unknown. New Zealand White (NZW) mice are considered healthy animals although they convey a genetic predisposition for immune complex-mediated glomerulonephritis. Here we show that NZW mice developed age-dependent lupus-prone autoimmune response and immune complex-mediated glomerulonephritis characterized by elevated GPBP, glomerular basement membrane (GBM) collagen disorganization and expansion, and deposits of IgA on disrupted GBM. Transgenic overexpression of human GPBP (hGPBP) in non-lupus-prone mice triggered similar glomerular abnormalities including deposits of IgA on a capillary GBM that underwent dissociation, in the absence of an evident autoimmune response. We provide in vivo evidence that GPBP regulates GBM collagen organization and its elevated expression causes dissociation and subsequent accumulation of IgA on the GBM. Finally, we describe a previously unrecognized pathogenic mechanism that may be relevant in human primary immune complex-mediated glomerulonephritis.

Structural and functional salivary disorders in type 2 diabetic patients.

UNLABELLED: Diabetes mellitus type 2 is the most common metabolic disorder and it causes an important morbimortality. The structural modifications in the parotid gland (sialosis) had already been described in these patients and could result in variations in the salivary composition, as well as an increase in periodontal and dental pathology. OBJECTIVES: To compare the biochemical findings in the saliva and to correlate these biochemical disturbances with the morphologic findings previously described. PATIENTS AND METHODS: Clinical information were gathered about 33 patients, 17 had type 2 diabetes. Samples of whole saliva were obtained for biochemical analysis and serum samples to determine metabolic control. RESULTS: In the diabetics saliva we found urea and total proteins increased and reduced levels of microalbumina. Salivary glucose was only augmented in patients with poor metabolic control. Clinical symptoms of xerostomia were present in 76,4% and dental and periodontal disease in 100%. The parotid gland was characterised by the presence of small acini, lipid intracytoplasmic droplets, as well as adipose stroma infiltration. The acinar cytoqueratins expression was heterogeneous and very positive in the hyperplasic ducts. CONCLUSIONS: These biochemical disorders in the saliva of the type 2 diabetic patients would be related with the structural changes previously observed in parotid glands.

Alteraciones salivares en pacientes con diabetes tipo 2 / Structural and functional salivary disorders in type 2 diabetic patients

La diabetes mellitus tipo 2 es el desorden metabólico más frecuente, siendo además causante de una importante morbi-mortalidad. En estos pacientes se han descrito alteraciones estructurales de la parotida (sialosis) que podrían comportar modificaciones en la composición salivar, así como un incremento de patología dental y periodontal. Objetivos: establecer las alteraciones bioquímicas de la saliva y su posible correlación con los hallazgos morfológicos. Diseño del estudio: se realizo un estudio clínico de 33 pacientes, 17 de ellos con diabetes tipo 2. Se recogieron muestras de saliva para análisis bioquímico y suero para control metabólico.Resultados: en la saliva de los pacientes diabéticos encontramos un incremento de la urea y las proteínas totales, así como una reducción de la microalbumina. La glucosa salivar estaba solo aumentada en los diabéticos con mal control metabólico. Los síntomas de xerostomía se detectaron en el 76,4% de los casos y las lesiones dentales y periodontales en el 100% de los pacientes. Conclusión: estos desordenes bioquímicos en la saliva de los pacientes con diabetes tipo 2 se pueden correlacionar con las alteraciones estructurales descritas previamente

Diabetes mellitus type 2 is the most common metabolic disorder and it causes an important morbimortality. The structural modifications in the parotid gland (sialosis) had already been described in these patients and could result in variations in the salivary composition, as well as an increase in periodontal and dental pathology. Objectives: to compare the biochemical findings in the saliva and to correlate these biochemical disturbances with the morphologic findings previously described.Patients and methods: clinical information were gathered about 33 patients, 17 had type 2 diabetes. Samples of whole saliva were obtained for biochemical analysis and serum samples to determine metabolic control. Results: in the diabetics saliva we found urea and total proteins increased and reduced levels of microalbumina. Salivary glucose was only augmented in patients with poor metabolic control. Clinical symptoms of xerostomia were present in 76,4% and dental and periodontal disease in 100%. The parotid gland was characterised by the presence of small acini, lipid intracytoplasmic droplets, as well as adipose stroma infiltration. The acinar cytoqueratins’ expression was heterogeneous and very positive in the hyperplasic ducts

Structural differences between alcoholic and diabetic parotid sialosis.

UNLABELLED: Between the sialosis' etiologic agents, we can find the chronic alcoholism and diabetes. Both nosologic entities are described using a similar histopathologic pattern. OBJECTIVES: The purpose of this work has been analyzing and comparing the histopathological differences between the diabetic and alcoholic sialosis. STUDY DESIGN: We studied 7 parotid glands samples of diabetic patients and 4 samples of normal glands obtained from surgical material were used as a control. For the comparative study, we used 12 parotid glands from chronic alcoholic patients with clinical diagnosis of cirrhosis and 6 autopsies on individuals who had died from alcoholic hepatic cirrhosis. This material was fixed in formaline, processed for embedding in paraffin, standard coloration techniques and immunotechnique for cytokeratin EA/1 y EA/3. RESULTS: In the cases of diabetics, the parotid gland was characterised by the presence of small acini, a bigger number of lipid intracytoplasmic droplets in the acinar and ductal cells, as well as an abundant adipose infiltration in the stroma when compared to the alcoholics. We observed that the cytokeratins' expression was heterogeneous at the acinar level, and very positive in the hyperplasic ducts, compared to the alcoholic and control groups. CONCLUSIONS: These qualitative valorations indicate the differences between the histopathologic pattern of sialosis with different origins.

Diferencias estructurales entre las sialosis parotidea de etiología diabética y alcohólica / Structural differences between alcoholic and diabetic parotid sialosis

Entre los agentes etiológicos de la sialosis se citan el alcoholismo crónico y la diabetes. Ambas entidades nosológicas se describen con un cuadro histopatológico similar.Objetivos: El objetivo de este trabajo fue analizar y comparar las modificaciones estructurales de la sialosis diabética con las de etiología alcohólica.Diseño del estudio: Se analizaron 7 biopsias de glándula parótida de individuos diabéticos y 4 de pacientes no diabéticos (controles), con patología oncológica en regiones vecinas. El estudio comparativo se efectuó con muestras de archivo que comprendieron 12 biopsias parotídeas de pacientes con diagnóstico clínico de cirrosis hepática alcohólica y 6 autopsias de individuos que fallecieron por cirrosis hepática alcohólica. El material fijado en formol e incluído en parafina, se coloreó con técnicas de rutina y se marcó con anticuerpos para citoqueratinas EA/1 y EA/3.Resultados: En los diabéticos, la parótida se caracterizó por presentar acinos de tamaño más reducido, mayor cantidad de inclusiones lipídicas intracitoplasmáticas en las células acinares y ductales e infiltración grasa abundante en el estroma, comparado con los alcohólicos. Se observó que la expresión de citoqueratinas fue heterogénea a nivel de los acinos e intensamente positiva en los ductos hiperplásicos, comparada con los grupos alcohólico y control.Conclusion: Estas valoraciones cualitativas indican diferencias en el cuadro histopatológico entre estas sialosis de distinto origen

Between the sialosis’ etiologic agents, we can find the chronic alcoholism and diabetes. Both nosologic entities are descirbed using a similar histopathologic pattern. ;;Objectives: The purpose of this work has been analyzing and comparing the histopathological differences between the diabetic and alcoholic sialosis.Study design: We studied 7 parotid glands samples of diabetic patients and 4 samples of normal glands obtained from surgical material were used as a control. For the comparative study, we used 12 parotid glands from chronic alcoholic patients with clinical diagnosis of cirrhosis and 6 autopsies on individuals who had died from alcoholic hepatic cirrhosis. This material was fixed in formaline, processed for embedding in paraffin, standart coloration techniques and immunotechnique for cytokeratin EA/1 y EA/3. ;;Results: In the cases of diabetics, the parotid gland was characterised by the presence of small acini, a bigger number of lipid intracytoplasmic droplets in the acinar and ductal cells, as well as an abundant adipose infiltration in the stroma when compared to the alcoholics. We observed that the cytoqueratins’ expression was heterogeneous at the acinar level, and very positive in the hyperplasic ducts, compared to the alcoholic and control groups. ;;Conclusions: These qualitative valorations indicate the differences between the histopathologic pattern of sialosis with different origins

Ultrastructural patterns of primary ciliar dyskinesia syndrome.

Clinical presentation, ciliary ultrastructure, and nasal mucociliary transport by a radioisotopic technique were analyzed in 14 Kartagener syndrome patients. In this study the most common pattern was the absence of outer and inner dynein arms in 57% of cases. Also reported are 14% patients with short inner dynein arms. A total of 29% of the patients showed normal dynein arms. Mucociliary stasis was observed in 13 cases. Primary ciliary dyskinesia syndrome and Kartagener syndrome are clinically homogeneous and morphologically heterogeneous. The authors conclude that a typical clinical presentation with an altered mucociliary transport obtained by radioisotopic technique is diagnostic although ciliary ultrastructure is normal.

Anaplastic carcinoma of the thyroid with rhabdomyosarcomatous differentiation: a report of two cases.

Anaplastic carcinoma of the thyroid gland (ACT) is a highly malignant tumor that is almost invariably associated with a fatal outcome. It demonstrates a variety of peculiar histological features, with squamoid, giant cell and spindle cell growth patterns. The spindle cell variant of ACT is usually indistinguishable from a true sarcoma and it can simulate fibrosarcoma, malignant fibrous histiocytoma (MFH), hemangiopericytoma and angiosarcoma or rhabdomyosarcoma. Although a rhabdomyosarcomatous appearance has sometimes been mentioned in the literature, true skeletal muscle differentiation has never been consistently proved. We report two cases of ACT with rhabdomyosarcomatous differentiation, as demonstrated by means of immunohistochemistry and electron microscopy. Both cases disclosed a very similar histological appearance, with a main population of small, pleomorphic, round-to-oval cells arranged in a storiform pattern, admixed with scattered pleomorphic giant cells, an image similar to that of the usual type of MFH. Stains for epithelial markers showed only few, scattered, weakly positive cells. Thyroglobulin and calcitonin were negative in tumor cells in both cases. On the contrary, positivity to vimentin was strong and generalized. Immunomarkers of muscular differentiation showed a consistent positivity. At the ultrastructural level, the cells disclosed the same spindle and pleomorphic morphology, with large, bizarre nuclei and cytoplasm with abundant mitochondria, rough endoplasmic reticulum, secretory granules and lipid droplets. There were also cells with wide cytoplasm filled with filamentous material, either of actin or myosin, as well as Z-band material. In conclusion, the cases reported here show a clear-cut rhabdomyosarcomatous differentiation of ACT, confirmed both immunohistochemically and ultrastructurally, a feature not previously reported in the literature. These findings may contribute to the broadening of the differentiation spectrum of this unusual neoplasm.

Alcoholic parotid sialosis: a structural and ultrastructural study.

OBJECTIVES: The purpose of this study is to demonstrate the histopathological differences between the initial and advanced stages of Alcoholic Sialosis, a pathology that generally involves parotid hypertrophy and structurally affects, to diverse degrees, the other salivary glands. STUDY DESIGN: An analysis and comparison was carried out of the structural and ultrastructural modifications of the parotid glands from the hepatic biopsies of chronic alcoholics with clinical diagnosis of cirrhosis and from autopsies on individuals who had died from alcoholic hepatic cirrhosis. Various samples of normal gland obtained from surgical material were used as a control. RESULTS: The alterations found in the biopsies corresponded to the modifications discovered in the autopsies of alcoholics. Notable in both cases was the massive accumulation of secretory granules of different size, shape and electrodensity, which occupied the cytoplasm of the acinar cells. In both sample types the excretory ducts were enlarged and the epithelium of the striate ducts presented cells with nuclei and cytoplasm of irregular appearance and arrangement. A moderate adipose infiltration in the stroma and slight periacinal edema was also observed. The biopsies revealed, both at optical and electron microscopical levels, lipid inclusions in the acinar cells and the glandular parenchymal ducts. CONCLUSIONS: The structural and ultrastructural findings of the parotid biopsies and autopsies, clearly show that alterations are already present in the salivary glands of chronic alcoholics before the terminal phase of hepatic cirrhosis. The enlargement of the ductal system lumens could be the principal cause of glandular hypertrophy.

Sialosis Parotídea Alcohólica: estudio estructural y ultraestructural / Alcoholic parotid sialosis: a structural a ultrastructural study

Objetivos. El propósito del presente trabajo fue establecer posibles diferencias histopatológicas entre los estadíos iniciales y terminales de la sialosis alcohólica, patología que generalmente involucra hipertrofia parotídea y afecta estructuralmente en diverso grado a las demás glándulas salivales. Diseño del estudio. se analizaron y compararon las modificaciones estructurales y ultraestructurales de glándulas parótidas provenientes de: A) biopsias de alcohólicos crónicos con diagnóstico clínico de cirrosis hepática, de las que una fracción fue procesada para microscopía óptica (MO) y otra fracción fue fijada en glutaraldehído y procesada para microscopía electrónica de trasmisión (MET) Jeol JEM 1010 B) autopsias de individuos fallecidos por cirrosis hepática alcohólica, procesadas para MO y re-procesadas posteriormente para MET. Una porción de glándula normal obtenida de material quirúrgico fue usada como control. Resultados. Las alteraciones encontradas en las biopsias son considerablemente comparables a las modificaciones encontradas en las autopsias de alcohólicos, especialmente debido a la acumulación de gránulos secretorios de diferente tamaño, forma y electrodensidad, generalmente ocupando todo el citoplasma de las células acinares. En ambos tipos de muestras los ductos excretores se encontraban dilatados y el epitelio de los conductos estriados presentaba células claras y oscuras, con núcleos de aspecto y disposición irregular. Se observó asimismo moderada infiltración grasa en el estroma y leve edema periacinar. En las biopsias se observaron al MO y MET inclusiones lipídicas en las células acinares y ductales del parénquima glandular. Conclusiones. Los resultados estructurales y ultraestructurales encontrados en biopsias y autopsias de parótidas, ponen de manifiesto que las alteraciones ya están presentes en las glándulas salivales de alcohólicos crónicos antes de la etapa terminal de la cirrosis hepática. La dilatación de los lúmenes del sistema ductal podría ser la principal responsable de la hipertrofia glandular (AU)