Histology and histopathology Vol.22, nº 9 (2007)
Ir a Estadísticas
Permanent URI for this collection
Browse
Recent Submissions
- PublicationOpen AccessTrichloroethylene exposure elicits damage in epididymal epithelium and spermatozoa in mice(Murcia : F. Hernández, 2012-05-21) Kan, F.W.K.; Forkert, P.G.; Wade, M.G.We have investigated the toxic effects of trichloroethylene (TCE) on the epididymis and epididymal sperm in mice. Mice were exposed to TCE (1000 ppm) by inhalation for 6 h/day for 5 days/week for 1 to 4 weeks. Segments of the epididymis (caput, corpus and cauda) were examined by light and electron microscopy. At the light microscopic level, degeneration and sloughing of epithelial cells were evident as early as 1 week after TCE exposure, and were most pronounced after 4 weeks. Such epithelial damage was observed in the caput, corpus and cauda regions of the epididymis. Ultrastructural observations revealed vesiculation in the cytoplasm, disintegration of basolateral cell membranes, and sloughing of epithelial cells. Sperm were found in situ in the cytoplasm of degenerated epididymal cells. Additionally, a large number of sperm in the epididymal lumen exhibited abnormalities including malformation of head and tail components. Our results demonstrated that exposure to TCE by inhalation causes damage to the epididymal epithelium and sperm.
- PublicationOpen AccessPrenatal corticosterone influences the trajectory of neuronal development, delaying or accelerating aspects of the Purkinje cell differentiation(Murcia : F. Hernández, 2007) Rugerio-Vargas, C.; Ramírez-Escoto, M.; DelaRosa-Rugerio, C.; Rivas-Manzano, P.The nervous system developmental programs proceed in orderly fashion following strict timetables. However, the mechanisms regulating developmental timing remain largely unknown. Increases or decreases in glucocorticoids in the fetal brain can be detrimental. We present evidence supporting that corticosterone forwards the migration of cerebellar granule neurons when applied acutely during pregnancy. This change in developmental tempo enhances dendritic growth of Purkinje neurons, increases the nuclear area, accelerates perinucleolar rosette appearance and decreases the development of Nissl bodies. Our observations thus support that forwarding the occurrence of developmental events does not always arrest neuronal growth, as some heterochronic developmental models imply. We suggest that prenatal glucocorticoids alter the trajectory of Purkinje neurons development soon after birth. These changes could represent a transient condition or could produce medium or long-term later consequences. More studies are needed to evaluate these intriguing possibilities
- PublicationOpen AccessExpression pattern of squamous cell carcinoma antigen in oesophageal dysplasia and squamous cell carcinoma(Murcia : F. Hernández, 2007) Parenti, Anna; Porzionato, A.; Pizzi, S.; Guzzardo, V.; Fassina, G.; Macchi, Verónica; Ninfo, V.; De Caro, RaffaelleThe aim of the present study was to evaluate the tissue expression of squamous cell carcinoma antigen (SCCA) in oesophageal dysplasia and squamous cell carcinoma (SCC) with reference to its clinicopathologic and prognostic significance. Immunohistochemistry using SCCA polyclonal antibody was performed on SCCs from 61 surgical oesophagectomies. Fifteen cases of low-grade dysplasia (LGD) and 37 noncoexistent high-grade dysplasia (HGD) were also sampled from these materials, together with sixteen chronic cases of oesophagitis. SCCA immunoreactivity was present in the maturative compartments of all normal epithelia and oesophagitis. LGDs showed no SCCA immunoreactivity in the dysplastic proliferative component but only in the superficial normal layers. In 94.6% of HGDs, no SCCA immunoreactivity was detected throughout the thickness of the epithelium. In SCCs, SCCA expression higher than 25% was found in 54% of cases. SCCA positivity showed an inverse correlation with histological grade, whereas no statistically significant correlation was found with TNM classifications, stage, or survival. SCCA is not expressed in early oesophageal carcinogenesis but, in SCC, it represents an indicator of histologic differentiation. In differentiated SCC, SCCA may represent a negative factor for cancer invasiveness, through inhibition of proteases
- PublicationOpen AccessThe S100 proteins for screening and prognostic grading of bladder cancer(Murcia : F. Hernández, 2007) Yao, R.; Davidson, D.D.; López Beltrán, A.; MacLennan, G.T.; Montironi, R.; Cheng, L.The S100 gene family, which is composed of at least 24 members carrying the Ca2+ binding EF-hand motif, has been implicated in both intracellular and extracellular functions, including enzyme activities, immune responses, cytoskeleton dynamics, Ca2+ homeostasis, cell growth and cell differentiation. Altered S100 protein levels are associated with a broad range of diseases, including cardiomyopathy, inflammatory and immune disorders, neurodegenerative disorders and cancer. Although the precise role of S100 protein in carcinogenesis is poorly understood, it seems that formation of homo- and hetero-dimers, binding of Ca2+ and interaction with effector molecules are essential for the development and progression of many cancers. Several studies have suggested that S100 proteins promote cancer progression and metastasis through cell survival and apoptosis pathways. In animal models of bladder cancer, several S100 proteins are differentially expressed in bladder tumors relative to normal urothelium. In human bladder cancer, overexpression of S100A4, S100A8 or S100A11 are associated with stage progression, invasion, metastasis and poor survival. This review summarizes these findings and evaluates their implications for human bladder cancer management
- PublicationOpen AccessIntervertebral disc biology, degeneration and novel tissue engineering and regenerative medicine therapies(Murcia : F. Hernández, 2007) Richardson, S.; Mobasheri, A.; Freemont, A.J.; Hoyland, J.A.Degeneration of the intervertebral disc (IVD) is a major cause of low back pain affecting a large percentage of the population at some point in their lives. Consequently IVD degeneration and its associated low back pain has a huge socio-economic impact and places a burden on health services world-wide. Current treatments remove the symptoms without treating the underlying problem and can result in reoccurrence in the same or adjacent discs. Tissue engineering offers hope that new therapies can be developed which can regenerate the IVD. Combined with this, development of novel biomaterials and an increased understanding of mesenchymal stem cell and IVD cell biology mean that tissue engineering of the IVD may soon become a reality. However for any regenerative medicine approach to be successful there must first be an understanding of the biology of the tissue and the pathophysiology of the disease process. This review covers these key areas and gives an overview of the recent developments in the fields of biomaterials, cell biology and tissue engineering of the IVD.
- «
- 1 (current)
- 2
- 3
- »