Showing papers in "Journal of Histology in 2014"

Alterations in the Gill Filaments and Secondary Lamellae of Cirrhinus mrigala Exposed to “Nuvan,” an Organophosphorus Insecticide

Abstract: The alterations in the epithelium of the gill filaments and the secondary lamellae of the gills of Cirrhinus mrigala, on exposure to “Nuvan,” have been explored in the present investigation using light and scanning electron microscopy. The fishes were exposed to two sublethal concentrations, 5 mg/L and 15 mg/L, of “Nuvan.” The changes are more rapid and intensive at higher concentration than at lower concentration, suggesting that the changes are dose dependent. Increase in thickness of epithelium covering secondary lamellae, merger of epithelium of gill filaments and adjacent secondary lamellae, and aneurysm is considered to reduce efficiency of gills for gaseous exchange. A significant decline in the density and area of the mucous goblet cells in the epithelium of the gill filaments and the secondary lamellae of C. mrigala exposed to “Nuvan” could be correlated with excessive loss of the secretory contents of these cells, uncompensated by their production in sufficient quantities. The histopathological changes, in general, take longer time to recover in the fishes exposed to 15 mg/L than those exposed to 5 mg/L indicating that the changes in fishes exposed to higher concentration are more severe than those at lower concentration of the insecticide.

Comparative Histomorphological and Histochemical Studies on the Oesophagus of Nile Tilapia Oreochromis niloticus and African Catfish Clarias gariepinus

Abstract: The present work aimed to describe and compare both gross and microscopic structure of the oesophagus of Nile tilapia (Oreochromis niloticus) and African catfish (Clarias gariepinus). For this purpose, 60 specimens of oesophagus of Nile tilapia (omnivorous fish) and African catfish (carnivorous fish) were collected and processed. Anatomically, the oesophagus of both species appeared as a short tube with longitudinal mucosal folds. Using scanning electron microscope, the epithelial surface of the esophagus showed primary and secondary mucosal folds in both species while tertiary folds were observed in that of tilapia only. Histologically, the oesophagus consisted of four distinct layers: mucosa, submucosa, muscularis, and serosa. The oesophageal mucosa consisted of stratified epithelium with few mucous secreting cells in catfish and many mucous secreting cells in tilapia. Two types of mucous secreting cells reacted positively with both periodic acid shiff (PAS) and alcian blue (AB); rounded and elongated cells that were recognized in the esophageal epithelium of tilapia and only elongated oval cells were observed in that of catfish. In conclusion, the obtained histomorphological differences in esophagus of both fish species may be attributed to their different feeding habits and type of food.

Histochemical and Immunohistochemical Analysis of the Stomach of Rhinella icterica (Anura, Bufonidae)

Abstract: The stomach of Rhinella icterica was analyzed at light microscopy, employing histochemical techniques, lectin histochemistry, and immunohistochemistry for identifying enteroendocrine cells (EC). Although the stomach was composed of fundic and pyloric regions, its wall is formed by mucosa, submucosa, muscularis, and serosa. The mucosa was lined by a simple columnar mucous epithelium, supported by loose connective tissue. Several tubular, simple glands were composed of mucous neck cells, containing oxynticopeptic cells and EC cells. The mucous neck cells were rich in neutral glycoconjugates. The oxynticopeptic cells were predominant in fundic glands, exhibiting weaker alcianophilic reaction at their apical cytoplasm. Serotonin (5-HT) immunoreactive (IR) cells occurred throughout the entire stomach, preferentially located among mucous cells at upper part of the fundic glands. The muscularis mucosae, formed of smooth muscle, separated the mucosal layer from the submucosa, both of which were constituted by loose connective tissue, but without glands. Lymphoid modules occurred in the mucosa at the boundary at the stomach and the gut. In addition, the muscularis was constituted by two sublayers, the circular internal and the longitudinal external, being recovered by the connective tissue of the serosa.

Histology and Histometric Anatomy of the Male Reproductive System of Bat (Eidolon helvum)

Abstract: The male reproductive system of fruit bat (Eidolon helvum) was studied histologically using light microscope. Thirty males (17 adults and 13 juveniles) were captured using net, weighed, aged using relative ossification of the wing bone, and dissected and reproductive tissue was processed for histomorphometry. On the basis of histological sections, the structures of a pair of testis containing the seminiferous tubules of adults were compacted in organization with spermatogenic cells. The epididymis has a thinner muscular region than the vas deferens with longitudinal folds on the mucosal lining. Two portions were observed in the prostate gland, while seminal vesicle has numerous trabeculae and bulbourethral gland was observed to have multiacini. There was increase in thickness of muscular region, epithelial height, and luminal diameter of epididymis and vas deferens between adults and juveniles. This work has documented the histology of the male reproductive system in bats, and ultrastructure and histochemistry are recommended for further insight into the reproductive biology.

The Histochemical Characterization of the Glycoconjugates in the Epidermal Mucous Cells of the Red Californian Earthworm, Eisenia foetida

Abstract: The aim of this study was to characterize the nature and regional distribution of the glycoconjugates secreted by epidermal mucous cells in Eisenia foetida (Annelida). Specimens were divided into six regions from anterior to posterior. The histochemistry was carried out by using standard histochemical methods. Histochemical staining properties of glycoconjugates in epidermal mucous cells were determined regionally. The epidermis of all regions contained strong to stronger PAS (

Tissue Expression of Low and High Molecular Weight Cytokeratins in Lung Carcinoma Sections: Its Correlation with Some Clinic-Pathological Features

Abstract: The tissue expression of low (LMW) and high (HMW) molecular weight cytokeratins and Ber-EP4 antigen in both small (SCLC) and non-small (NSCLC) cell lung carcinomas, as well as its correlation with a variety of clinic-pathological features, was evaluated. In general, 43/52 (82.7%) of NSCLC sections showed the expression of at least one type of cytokeratin while only 7/16 (43.7%) of SCLC were stained with both LMW cytokeratin and pan-cytokeratins antibodies. Remarkably, 18/52 (34.6%) of NSCLC were positive to both types of cytokeratins. However, none of SCLC showed this pattern of expression. In NSCLC patients, the increasing levels of HMW cytokeratins expression, as shown by 34βE12 antibody, correlated with the occurrence of disease recurrence (; Fisher’s exact test). Consequently, the expression of HMW cytokeratins was found to be associated with a poor 4-year overall survival of NSCLC patients (; Log rank test), not taking into account the histopathological classification of tumors. Similar results were obtained when 8-year overall survival was assessed (; Log rank test). Our results could suggest the assessment of HMW cytokeratins in a larger series of NSCLC samples in order to confirm the potential prognostic value of them.

PRKRA Localizes to Nuage Structures and the Ectoplasmic Specialization and Tubulobulbar Complexes in Rat and Mouse Testis

Abstract: The cytoplasmic RNA-induced silencing complex (RISC) contains dsRNA binding proteins, including PRKRA, TRBP, and Dicer. RISC localizes to P-bodies. The nuage of the spermatogenic cells has function similar to the P-bodies. We study whether PRKRA localizes to nuage of spermatogenic cells of rat and mouse. PRKRA localized to four types of nuage structures, including aggregates of 60–90 nm particles, irregularly-shaped perinuclear granules, and intermitochondrial cement of pachytene spermatocytes, and chromatoid bodies of round spermatids. In addition, PRKRA is associated with dense material surrounding tubulobulbar complexes and with the ectoplasmic specialization. The results suggest that PRKRA functions in the nuage as an element of RNA silencing system and plays unknown role in the ectoplasmic specialization and at the tubulobulbar complexes of Sertoli cells attaching the head of late spermatids.

Search for Conditions to Detect Epigenetic Marks and Nuclear Proteins in Immunostaining of the Testis and Cartilage

Abstract: The localization of nuclear proteins and modified histone tails changes during cell differentiation at the tissue as well as at the cellular level. Immunostaining in paraffin sections is the most powerful approach available to evaluate protein localization. Since nuclear proteins are sensitive to fixation, immunohistochemical conditions should be optimized in light of the particular antibodies and tissues employed. In this study, we searched for optimal conditions to detect histone modification at histone H3 lysine 9 (H3K9) and H3K9 methyltransferase G9a in the testis and cartilage in paraffin sections. In the testis, antigen retrieval (AR) was indispensable for detecting H3K9me1 and me3, G9a, and nuclear protein proliferating cell nuclear antigen (PCNA). With AR, shorter fixation times yielded better results for the detection of G9a and PCNA. Without AR, H3K9me2 and H3K9ac could be detected at shorter fixation times in primary spermatocytes of the testis. In contrast to the testis, all antibodies tested could detect their epitopes irrespective of AR application in the growth plate cartilage. Thus, conditions for the detection of epigenetic marks and nuclear proteins should be optimized in consideration of fixation time and AR application in different tissues and antibodies.