Histology and histopathology Vol.34, nº1 (2019)
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- PublicationOpen AccessUltrastructure and 3D transmission electron tomography of collagen fibrils and proteoglycans of swollen human corneal stroma(Universidad de Murcia. Departamento de Biología Celular e Histología, 2019) Akhtar, S.; Petrovski, G.; Albert, R.; Alkanaan, A.; Kirat, O.; Khan, A.D.; Almubrad, T.Background. The transparency of the cornea is regulated by the unique organization of collagen fibrils (CFs) which is maintained by proteoglycans (PGs). The interlacing of CF lamellae in the anterior stroma provides the biomechanical properties of the cornea. Objective. To investigate the alterations of CFs and PGs in the swollen cornea, with special reference to the anterior stroma by using electron microscopy and 3D ultrastructural tomography. Method. Nine healthy normal scleral corneal rings (age from 40 to 65 years) were hydrated individually in deionised water to induce swelling in the cornea. Three of them were hydrated for 2hr whereas the other three were hydrated for 48hr. The remaining three scleral normal corneal rings were used as a control.The corneas were processed for electron microscopy (E M) to study the CFs and PGs. Ultrathin sections were observed using transmission electron microscopy (JOEL 1400) and digital images of CFs, PGs and lamellae were captured using a bottom mounted Quemesa camera and iTEM Soft Imaging System. The software program ‘Composerx64, version 3.4.2.0’ was used to construct individual 3D images from 120 digital images taken from -60 to +60 degree angles. Results. The 3D tomography showed the degeneration of microfibrils within the CFs of the swollen cornea. The CF diameter was significantly reduced and the interfibrillar spacing significantly increased in both the 2hr and 48hr hydrated corneas compared to the normal cornea. Within the hydrated corneas, the CF diameter was smaller and the interfibrillar spacing was increased in the middle and posterior stroma compared to the anterior stroma. The PG area in both the 2hr and the 48hr hydrated cornea was reduced in the anterior stroma, whereas it was increased in middle and posterior stroma compared to the normal cornea. The density of the PGs in both the 2hr and the 48hr samples, was reduced compared to the density of PGs in the normal cornea. Conclusion. The CFs, PGs and lamellae had degenerated, caused by swelling. 3D imaging demonstrated that the impairment of the microfibrils and PGs within the CF, is caused by the excessive hydration or swelling in the anterior as well as in the middle and posterior stroma. The lamellae of the anterior stroma which provides the biomechanical strength in the normal cornea, had degenerated in the swollen corneas due to the presence of the damaged CFs and PGs.
- PublicationOpen AccessExpression of γ-tubulin in non-small cell lung cancer and effect on patient survival(Universidad de Murcia. Departamento de Biología Celular e Histología, 2019) Maounis, Nicoletta F.; Dráberová, Eduarda; Trakas, Nikos; Chorti, María; Riga, Dimitra; Tzannis, Kimon; Kanakis, Meletis; Voralu, Kirtanaa; Ellina, Eleni; Mahera, Eleni; Demonakou, Maria; Lioulias, Achilleas; Dráber, Pavel; Katsetos, Christos D.Introduction. It has been reported that overexpression and altered compartmentalization of γtubulin may contribute to tumorigenesis and tumor aggressiveness in a variety of human malignancies. We have shown that γ-tubulin expression and cellular distribution pattern is also altered in non-small cell lung cancer (NSCLC) (Histol. Histopathol. 2012; 27: 1183- 1194). In the present study we examined the relationship between γ-tubulin expression and patient overall survival (OS). Material and methods. Immunohistochemistry was performed, with well-characterized anti-γ-tubulin antibodies, on 109 formalin-fixed, paraffin-embedded NSCLC specimens (p-TNM stage IIII). γ-Tubulin labeling indexes (LIs) were determined, and the association of γ-tubulin expression with clinicopathological parameters was evaluated. To analyze OS rates according to γ-tubulin LIs, patients were categorized into three groups: those with low (0- 30%), intermediate (31-69%) or high (70-100%) γtubulin LI. Association of clinicopathological parameters and γ-tubulin with survival were examined using univariate and multivariate Cox regression analysis. Results. No statistically significant association was seen between γ-tubulin overexpression and histological type, tumor differentiation, p-TNM stage and adenocarcinoma subtyping. Longer survival was observed in the high γtubulin LI group of patients with p-TNM stages II+III when compared to intermediate or low γ-tubulin LI groups, but the difference was not statistically significant (p=0.066). On the other hand, when combined low and intermediate γ-tubulin LI groups (p-TNM stages II+III) where compared to high γ-tubulin LI group, statistically significant longer survival was observed in high γtubulin group (p=0.021). Conclusion. Our findings suggest that level of γ-tubulin expression may have an impact on patient survival at more advanced NSCLC stages.
- PublicationOpen AccessDistribution of bile acid receptor TGR5 in the gastrointestinal tract of dogs(Universidad de Murcia. Departamento de Biología Celular e Histología, 2019) Giaretta, Paula R.; Suchodolski, Jan S.; Blick, Anna K.; Steiner, Joerg M.; Lidbury, Jonathan A.; Rech, Raquel R.Takeda-G-protein-receptor-5 (TGR5) is a receptor for bile acids and its expression has been described in a variety of tissues and species. Characterization of TGR5 distribution and function has been investigated in drug discovery for the treatment of metabolic diseases in humans. Because dogs are one of the species used in biomedical research and share some similarities with human gastrointestinal diseases, the objective of this study was to characterize the distribution of TGR5 receptor in the canine species. This study characterizes the distribution of TGR5 receptor in the gastrointestinal tract, liver, gallbladder, and pancreas of 8 dogs. The distribution of TGR5 antigen and mRNA expression was investigated using immunohistochemistry and RNA in situ hybridization, respectively. TGR5 immunolabeling was located in the cell membrane or in the cell membrane and cytoplasm. TGR5 immunolabeling was broadly distributed in macrophages, endothelial cells, ganglion cells, and leiomyocytes throughout all the examined tissues. Epithelial cells from tongue, stomach to rectum, as well as from gallbladder, biliary and pancreatic ducts demonstrated TGR5 immunolabeling. In endocrine cells, TGR5 immunolabeling was observed in intestinal enteroendocrine cells and islets of Langerhans in the pancreas. The hepatocytes had a unique pattern of immunolabeling located on the canalicular surface of the cell membrane. TGR5 mRNA expression was located mainly in the nucleus and the only negative cells throughout all examined tissues were striated muscle from tongue and esophagus, muscularis mucosae, esophageal glands, and hepatic sinusoids. These findings indicate that the bile acid receptor TGR5 is ubiquitously distributed in the canine gastrointestinal tract.
- PublicationOpen AccessAutophagy related markers (Beclin-1 and ATG4B) are strongly expressed in Wilms' tumor and correlate with favorable histology(Universidad de Murcia. Departamento de Biología Celular e Histología, 2019) Guimei, Maha; Ahmed Eladl, Mohamed; Vinod Ranade, Anu; Manzoor, ShaistaBackground. Wilms’ tumor treatment has achieved great success in the last decade. Nevertheless, some cases still fail to respond to the current multimodality therapy. These cases fall mainly in the unfavorable histology group with very few belonging to the favorable histology group. In recent years, autophagy manipulation whether inhibition or stimulation has been shown to affect cancer cell behavior and has emerged as a novel mechanism to improve cancer cell response to currently used therapeutic regimens. Objective. The current study aimed to investigate the expression of autophagy related markers (ATG4B and Beclin1) in WT, its association with the different clinicpathological parameters and its impact on patient survival. Methods. Twenty-one formalin fixed paraffin embedded (FFPE) WT specimens were immunohistochemically stained using autophagy related markers; Beclin-1 and ATG4B. All clinical, radiological and follow up data were retrieved from the patient records. Results. All specimens showed positive expression of both Beclin-1 and ATG4B. The staining score for Beclin1 varied between 50 and 300, and its expression was significantly associated with favorable histology (p=0.007). Similarly, ATG4B expression was significantly higher in favorable histology tumors compared to unfavorable histology (p=0.046). A statistically significant positive correlation between Beclin-1 and ATG4B expression was observed. The cumulative disease-free survival in patients with favorable histology was significantly higher compared to patients with unfavorable histology (p=0.0027). Conclusions. Beclin-1 and ATG4B expression were both found to be statistically significant discriminators of survival. Collectively these findings suggest that the expression of autophagy-related markers is associated with a favorable histology and could predict better survival in these patients.
- PublicationOpen AccessType 1 diabetes mellitus induced low bone turnover in ovariectomized rats(2019) Liu, Bo; Feng, Wei; Hasegawa, Tomoka; Amizuka, Norio; Li, MinqiTo investigate type 1 diabetes mellitus (T1DM) affecting bone remodeling in the context of menopause in female rats. The animals were subjected to either ovariectomy (OVX) which was performed to mimic postmenopausal estrogen deficiency, and/or type 1 diabetes mellitus which was established by the intraabdominal administration of 50 mg/kg streptozotocin (STZ). Single-loaded groups were the OVX group and the STZ group, while the combined group was the OVX+STZ group. Bone histomorphometry was performed on the tibial metaphysis by Micro-CT scanning. Immunohistochemistry was used to assess the activity of osteoblast and osteoclast by counteracting with antibodies against their respective specific marker enzymes. The gene expression of key molecules involved in osteoblastic and osteoclastic signaling pathways were analyzed by RT-qPCR. The results showed a significant bone volume decrease in both single-loaded groups and combined group with the combined group suffering greatest bone loss and bone structural deterioration (p<0.001). Immunohistochemical staining and RT-qPCR revealed an increase in osteoblastic (p<0.001) and osteoclastic (p<0.01) activities in OVX rats while there was a decrease (p<0.05) in those of STZ rats. When OVX and STZ were combined, the rats exhibited a further decrease in osteoblastic activity (p<0.001) and a similar level of osteoclastic activity (p>0.05) compared to their STZ counterparts. These results demonstrated that STZinduced T1DM reverses OVX-associated high bone turnover osteoporosis to the type of low bone turnover, leading to greater bone loss and structural defect.