Biomedical subjects

G L Tipoe

Publications and source records attributed to G L Tipoe.

35 records · Page 2Linked to original sources

PubMed2001

Dietary saturated fatty acids reverse inflammatory and fibrotic changes in rat liver despite continued ethanol administration.

We investigated the potential of dietary saturated fatty acids to reverse alcoholic liver injury despite continued administration of alcohol. Five groups (six rats/group) of male Wistar rats were studied. Rats in groups 1 and 2 were fed a fish oil-ethanol diet for 8 and 6 weeks, respectively. Rats in groups 3 and 4 were fed fish oil and ethanol for 6 weeks before being switched to isocaloric diets containing ethanol with palm oil (group 3) or medium-chain triglycerides (MCTs, group 4) for 2 weeks. Rats in group 5 were fed fish oil and dextrose for 8 weeks. Liver samples were analyzed for histopathology, lipid peroxidation, nuclear factor-kappaB (NF-kappaB) activation, and mRNAs for cyclooxygenase-2 (Cox-2) and tumor necrosis factor-alpha (TNF-alpha). Endotoxin in plasma was determined. The most severe inflammation and fibrosis were detected in groups 1 and 2, as were the highest levels of endotoxin, lipid peroxidation, activation of NF-kappaB, and mRNAs for Cox-2 and TNF-alpha. After the rats were switched to palm oil or MCT, there was marked histological improvement with decreased levels of endotoxin and lipid peroxidation, absence of NF-kappaB activation, and reduced expression of TNF-alpha and Cox-2. A diet enriched in saturated fatty acids effectively reverses alcohol-induced necrosis, inflammation, and fibrosis despite continued alcohol consumption. The therapeutic effects of saturated fatty acids may be explained, at least in part, by reduced endotoxemia and lipid peroxidation, which in turn result in decreased activation of NF-kappaB and reduced levels of TNF-alpha and Cox-2.

Aniline Hydroxylase↗

PubMed2001

Arginine reverses ethanol-induced inflammatory and fibrotic changes in liver despite continued ethanol administration.

We investigated the potential of arginine to reverse pathological changes in alcohol-induced liver injury. Four groups (six rats/group) of male Wistar rats were fed a fish oil-ethanol diet for 6 (group 2) or 8 (group 1) weeks. Rats in group 3 were fed fish oil-ethanol for 6 weeks, after which they were administered arginine with fish oil-ethanol for an additional 2 weeks. Rats in group 4 were fed fish oil-dextrose for 8 weeks. Liver samples were analyzed for histopathology, lipid peroxidation, cytochrome P4502E1 activity, nuclear factor-kappaB, and levels of messenger RNA for tumor necrosis factor-alpha, cyclooxygenase-2, and inducible nitric oxide synthase. Concentrations of endotoxin were measured in plasma. The most severe inflammation and fibrosis was detected in groups 1 and 2, as were the highest levels of endotoxin, lipid peroxidation, cytochrome P450 2E1 activity, activation of nuclear factor-kappaB, and mRNA levels for tumor necrosis factor-alpha, cyclooxygenase-2, and inducible nitric oxide synthase. Plasma nitric oxide was also increased as was nitrotyrosine in liver. After arginine was administered, there was marked improvement in the pathological changes accompanied by decreased levels of endotoxin, lipid peroxidation, activation of nuclear factor-kappaB, tumor necrosis factor-alpha, cyclooxygenase-2, inducible nitric oxide, and nitrotyrosine staining. The therapeutic effects of arginine are probably secondary to increased levels of nitric oxide but other effects of arginine cannot be excluded.

Animals↗

PubMed2000

Alteration in the expression of bone morphogenetic protein-2,3,4,5 mRNA during pathogenesis of cleft palate in BALB/c mice.

To identify the function of these bone morphogenetic proteins (BMP) during pathogenesis of cleft palate, an experimental model was established in BALB/c mice. Cleft palate was induced by exposure to retinoic acid on embryonic day (E)12. The expression of BMP-2,3,4,5 mRNA in normal and abnormal embryonic palatal shelves was then examined from E13 to E16 by in situ hybridization. The results showed that BMP-4 mRNA was expressed strongly and uniformly in normal epithelial cells and dispersed mesenchymal cells on E13. BMP-2,5 mRNA expression appeared only in dispersed mesenchymal cells. With the development of shelves, the staining density of BMP-2,4,5 decreased gradually in mesenchymal cells outside of the condensation and increased inside the condensation. After shelves had fused on E16, no positive signals for BMP-2,4,5 were detected in dispersed mesenchymal cells, but their expression persisted in the condensation. Exposure to retinoic acid delayed the formation of the condensation and decreased BMP-2,4,5 mRNA dramatically in mesenchyme from E13 to E15. BMP-3 mRNA expression were almost negative in either control or retinoic acid-treated groups during all stages. It was concluded that spatial and temporal expression of BMP-2,4,5 was required during normal palatogenesis, and that a deficiency of their mRNA expression may contribute to the pathogenesis of cleft palate.

Animals↗

PubMed2000

Induction of apoptosis by hexamethylene bisacetamide is p53-dependent associated with telomerase activity but not with terminal differentiation.

The present study investigated the relationships amongst apoptosis, terminal differentiation and telomerase activity in human colon carcinoma cells. We found that hexamethylene bisacetamide (HMBA) induced apoptosis in human colon carcinoma LoVo cells harbouring wild-type p53 but not in SW1116 cells harbouring mutant p53. HMBA reduced telomerase activity in both colon carcinoma cells but it did not induce differentiation in the colon carcinoma cells. Taken together, our results suggest that HMBA can induce apoptosis via a p53-dependent pathway, but apoptosis and terminal differentiation may be separately regulated in LoVo cells. Inhibition of telomerase activity may activate apoptosis through a p53-dependent mechanism.

Acetamides↗

PubMed2000

[Analysis of the expression of BMP-2,3,4,5 in nerve sheath tumors of maxillofacial region].

OBJECTIVE: The aim of present study is to elucidate the relationship between the members of BMP family and the neoplasms of peripheral nerve. METHODS: Eight cases of schwannoma and three cases of malignant schwannoma were collected and all samples were fixed with 10% neutral formalin and embedded in paraffin wax. Five microns thickness sections were prepared for staining with haematoxylin and eosin for histopathological assessment and processed for in situ hybridization for assessing the mRNA transcriptions of BMP-2,3,4,5. Sections of osteosarcoma that previously demonstrated consistent expression of BMP-2 mRNA were included in each batch of staining to serve as positive control. RESULTS: The results showed that all of the neoplastic lesions of nerve sheath showed a consistent expression of BMP-2,3,4,5. The positive signals of benign lesions were obviously increased in the palisading area or the area of accumulated cells. There was no detectable staining in the matrix of tumour and collagenous fiber. The staining intensity was relatively and slightly weak in cells of Antoni B tissue when compared with Antoni A tissue. Nevertheless, the tumour cells in Antoni B tissue also showed BMP-2,3,4 and 5 positively staining. The fibroblasts of schwannoma were negatively stained. The malignant lesions showed higher expression signals of BMPs than benign lesions. CONCLUSION: The results can be concluded that the selected members of BMPs may be involved in the process of growth and progression of the neoplasms of peripheral nerve.

Adult↗

PubMed2000

[The quantitative analysis of cyclin D1 expression in RA-treated and non-RA-treated ectomesenchymal cells in vitro].

OBJECTIVE: To elucidate the alteration of Cyclin D1 protein between RA-treated and the non-RA-treated ectomesenchymal cells in embryonic mice. METHODS: Ectomesenchymal cells in the developing orofacial processes were explanted from embryonic BALB/c mice on generation day 12(15) (the 15th hour of the 12th day). Primary cells were cultured using the tissue mass method. The variants of growth curves were examined in the RA-treated and normal groups. Protein of Cyclin D1 was detected using immunohistochemistry. The positive degree of Cyclin D1 staining was analyzed using image analysis. RESULTS: The findings showed that the growth of ectomesenchymal cells was inhibited dramatically. Cyclin D1 expressed strongly in normal ectomesenchymal cells. However, its expression decreased evidently after RA-treated. There was significant difference between the test group and the normal group (P < 0.01). CONCLUSION: Low expression of Cyclin D1 may contribute to the inhibition of ectomesenchymal cells. It is necessary for Cyclin D1 to express appropriately during the normal meiosis of ectomesenchymal cells.

Animals↗

PubMed1999

Proliferative activity as detected by immunostaining with Ki-67 and proliferating cell nuclear antigen in benign and malignant epithelial lesions of the human parotid gland.

OBJECTIVE: A retrospective immunohistochemical study of parotid gland lesions was designed to evaluate the diagnostic and prognostic value of the proliferating cell nuclear antigen (PCNA) and Ki-67 with monoclonal antibodies PC 10 and MIB-1, respectively. STUDY DESIGN: Tissue samples comprised normal parotid gland (N, n = 10), chronic sialadenitis (CS, n = 8), Warthin's tumor (W, n = 10), benign pleomorphic adenoma (BPA, n = 8), mucoepidermoid carcinoma (MEC, n = 13), carcinoma in pleomorphic adenoma (CPA, n = 8) and adenoid cystic carcinoma (ACC, n = 12). The morphometric parameters for PCNA and MIB-1 comprised the PI and MI labelling indices (the numerical percentage of positive nuclei), NAP and NAM (the numerical density of positive nuclei), and NPI and NMI (volume corrected index). RESULTS: The values of MIB-1 parameters increased progressively in benign lesions in comparison with the N group and in malignant neoplasms in comparison with nonneoplastic groups and benign lesions. Values for all parameters in BPA were significantly lower than those in malignant groups. Spearman rank correlation analysis showed a highly positive correlation between the morphometric parameters and severity of the lesions. The mean values of MI and NMI were significantly higher in patients who died of the malignant tumors than in those who survived. The same quantitative parameters for PCNA did not differ significantly from those obtained for MIB-1 and showed similar trends. CONCLUSION: PCNA and MIB-1 indices are reliable markers for discriminating between benign and malignant tumors of the parotid gland, and the parameters PI, MI, NPI and NMI may have prognostic applications.

Adenocarcinoma↗

PubMed1998

Techniques for rapid quantitative assessment of activity levels in small-group tutorials.

Two techniques for the rapid quantitative analysis of student participation in small-group teaching were investigated. In the first approach an observer, who also acted as a 'critical friend', recorded the length of individual contributions using a computer keyboard as a simple timing device. In the second approach, small-group sessions were recorded with a portable stereophonic audiotape recorder. The teacher was recorded on one channel, all students on the other. A computer program produced automated analysis of these small group interactions by computing relative amount of speech on each channel. Simple analysis produced automatically by the programs revealed the overall style of the tutorial--variably 'mini-lectures' by teachers with very little participation by the student body, rapid 'question and answer' sessions with about equal teacher/student body involvement or 'mini-presentations' by students with the teacher offering sparse comments in the manner of a facilitator. By presenting results in a graphic format, teachers can be given rapid objective feedback on their teaching style. Coupled with short verbal/non-verbal quizzes at the end of tutorials and information from other assessments, the value of using levels of participation as a measure of the efficiency of such small-group sessions can itself be assessed.

Computer-Assisted Instruction↗

PubMed1998

Quantitative assessment of normal and potentially premalignant epithelium at different levels of human colorectal crypts.

The present study uses morphometric techniques to assess whether altered differentiation patterns exist in PPM which might reflect its premalignant status. Samples were obtained from resected malignant lesions of large bowels of 10 Chinese patients. Normal (N) samples were biopsied from the margins of each resected large bowel. Potentially premalignant (PPM) mucosae were obtained from within 2 cm of the margins of the malignant lesions. Tissues were processed for histological examination and using strict criteria, colorectal crypts were divided into basal (B), intermediate (I) and surface (S) segments. Interactive digitisation of sections from each group was used to generate the following morphometric parameters in each segment: nuclear profile circularity indices (NSF and NCI); nuclear numerical density (NA and NV); the degree of deviation of the major nuclear axis in relation to the epithelial-connective junction (AGDMAX); cell height (CH); the distance between nuclear apex to cell apex (DNACA); the distance between cell base to nuclear apex (DCBNA); stratification index (SI)--the ratio of DCBNA and CH; and the volume density of mucous vacuoles in the reference epithelium (VVMV,EP). In comparisons of different segments within groups, the nuclei at the S segment of N and PPM crypts were more irregular and less circular in shape than nuclei from other segments. There was a shift of nuclear profile shape (NSF and NCI) from circular to ellipsiodal between B and S segments. In comparisons of similar segments between groups, no significant nuclear shape changes were detected in nuclei of PPM crypts when compared with nuclei in similar segments of N crypts and the pattern of nuclear shape alterations resembled those of normal crypts. In comparisons of different segments within groups of N and PPM crypts, AGDMAX, DNACA, DCBNA, CH and SI parameters demonstrated that epithelial cells at the I segments have more centrally positioned nuclei with the tallest epithelial height when compared with epithelial cells in other segments of both crypts. In B segments, nuclear NA and NV were almost double those of other segments in both N and PPM crypts, with marked reductions in these parameters between B and I segments. VVMV,EP was significantly highest in the I segment and significantly lowest in the S segment of both groups. Both N and PPM crypts showed similar trends in VVMV,EP within the crypt segments but when comparing similar segments between both crypts, a significant difference was detected only between S segments. The alterations of nuclear shape and packing densities, orientation and mucous content in N crypts were similarly expressed in PPM crypts and distinct differences in numerical density (NV) and stratification index existed in crypts between these two groups when comparing similar segments. All values in PPM were consistently lower when compared with N crypts. These preliminary observations may represent a subtly altered state of cellular differentiation in PPM which may be a reflection of early preneoplastic transformation.

Colorectal Neoplasms↗

PubMed1998

[Relationship between the mRNA transcriptions of bFGF and KGF in the carcinogenesis of oral mucosa].

The aim of the study was to determine the expressions and effects of KGF and bFGF of FGF superfamily in oral mucosa. The mRNA transcriptional levels of bFGF and KGF in dysplasia (DYS) and squamous cell carcinoma (SCC) of buccal mucosa were observed and evaluated by in situ hybridization method. The results showed that bFGF and KGF mRNA were expressed by the mesenchymal cells in both DYS and SCC groups, but not in any of the epithelial cells. The positive reactions were located in fibroblasts, endothelial cells and some of the chronic inflammatory cells. There is an increasing mRNA transcriptional level in SCC than in DYS. The results indicated that bFGF and KGF may not only enhance the neovascularization and formation of stroma by autocrine and paracrine action, but also involved in the growth of neoplastic cells.

Carcinoma, Squamous Cell↗

PubMed1997

The assessment of proliferating cell nuclear antigen (PCNA) immunostaining in human benign and malignant epithelial lesions of the parotid gland.

Immunoreactivity of proliferating cell nuclear antigen (PCNA) was assessed in formalin-fixed, paraffin-embedded sections from human normal parotid gland (N; n = 12), chronic sialadenitis (CS; n = 8), Warthin's tumour (W; n = 10), benign pleomorphic adenoma (BPA; n = 11), mucoepidermoid carcinoma (MEC; n = 14), carcinoma in pleomorphic adenoma (CPA; n = 10) and adenoid cystic carcinoma (ACC; n = 12) of the parotid gland, using the monoclonal antibody PC 10. The morphometric parameters measured comprised PCNA labelling induces (PI = the numerical percentage of PCNA positive nuclei) and volume densities of PCNA positive nuclei(VV, PEP = the relative volume of positive nuclei per unit volume of reference epithelium). All parameters were expressed in relation to total positive, as well as to strongly- and weakly-positive nuclei. In general, the values of PCNA parameters increased progressively in benign lesions in comparison with the N group, and in malignant neoplasms in comparison with non-neoplastic groups and benign lesions. The strongly-positive parameters showed more statistically significant differences than weakly-positive ones, suggesting that weakly-stained nuclei may include some non-cycling cells and, therefore, that weakly-positive parameters may not be reliable proliferation markers. Values for all parameters in CPA were significantly higher than those in BPA, suggesting that these parameters may be used as diagnostic discriminators. Spearman rank correlation analysis showed a highly positive correlation between the morphometric parameters and the severity of the lesions. Furthermore, the mean values of PISP were significantly higher in patients who died of the malignant tumours than in those patients who survived. Our results indicate that PCNA indices might be useful markers for discriminating between benign (BPA) and malignant tumours of the parotid gland and that the parameter PISP may have prognostic applications.

Adenocarcinoma↗

PubMed1997

p53 oncoprotein accumulation in adenoid cystic carcinoma of parotid and palatine salivary glands.

Previous studies have suggested that alterations of the p53 gene are the most common genetic abnormality in human cancer. The aims of the present study were to evaluate p53 protein (p53P) immunostaining in adenoid cystic carcinoma (ACC) of the salivary gland and to correlate the expression with patient survival. A total of 27 cases of ACC in the parotid gland (n = 12) and the minor palatine glands (n = 15) were studied, with ten cases each of normal parotid and palatine glands as non-neoplastic controls. Staining was performed with mouse monoclonal antibody DO-7 against p53 (Dako, USA) using the ABC method. Stained nuclei irrespective of intensity or frequency were considered as positive. The frequency of positive nuclei was evaluated as the p53P index (p53PI), the percentage of the total nuclei in the reference epithelium. Clinical survival data were available for patients for periods up to 156 months. Our data showed that no normal tissues showed immunoreactivity with p53P in their nuclei. Thirteen of 15 (87%) cases of palatal and two of 12 (17%) cases of parotid neoplasms stained with p53P and the p53PI ranged from 0.01 to 10%. The number of p53P positive tumors was significantly higher in palatal than in parotid neoplasms, suggesting that palatal ACCs may be more aggressive in comparison with parotid ACCs. Our data also showed that the number of p53P positive tumors was significantly increased in patients who died of tumors than in patients with no evidence of disease at the end of the follow-up period between 60 to 156 months. These results suggest that p53P may be involved in the development of salivary gland ACCs and that p53P analysis may be a useful indicator of poor prognosis.

Adolescent↗

PubMed1997

Expression of BMP-2 and TGF-beta 1 mRNA during healing of the rabbit mandible.

To identify the cell types which produce BMP and TGF-beta during fracture healing and to elucidate the interactions between BMP and TGF-beta in regulating cell proliferation and differentiation at various stages, an experimental model of fracture healing in the rabbit mandible was established and the expression of BMP-2 and TGF-beta 1 mRNA was studied at different healing stages by in situ hybridization. The results showed that undifferentiated mesenchymal cells, differentiating osteoblasts and chondroblasts, had higher levels of BMP-2 mRNA at the stage of intramembranous bone formation and early chondrogenesis, while the level of TGF-beta 1 mRNA was higher in chondrocytes and active differentiated osteoblasts during chondrogenesis and endochondral ossification, respectively. We conclude that BMP-2 expression was correlated with the differentiation of mesenchymal cells into osteoblasts and chondrocytes. TGF-beta 1 mRNA expression was closely associated with the active synthetic stage of osteoblasts and chondrocytes. These observations suggest that both BMP and TGF-beta are involved in the regulation of fracture healing. BMP may play an important role in bone induction and early chondrogenesis, while TGF-beta regulates the proliferation and active synthetic ability of chondrocytes and osteoblasts.

Animals↗

PubMed1996

The relationship between vascularity and cell proliferation in human normal and pathological lesions of the oral cheek epithelium.

The present study investigates relationships between neovascularisation and PCNA cell proliferation markers in different pathological lesions of the oral cheek mucosa. All specimens were fixed in 10% formalin and routinely processed for histology. Six normal (N) samples were taken from resection margins of benign lesions. The pathological lesions consisted of chronic inflammation (n = 10), lichen planus (n = 7), fibrous hyperplasia (n = 11), dysplasia (n = 5), squamous cell carcinoma (n = 22) and epithelium adjacent to carcinoma (n = 6). Adjacent 5 microns sections were stained with monoclonal antibodies against vimentin (clone no. V9) for identification of stromal blood vessels and against proliferating nuclear antigen (PCNA/PC10) using ABC immunoperoxidase techniques. Point counting was used to obtain the primary morphometric data using a Zeiss VIDAS image analyser. No attempt was made to classify the different types of blood vessels. The morphometric blood vessel parameters estimated were volume density, number per unit area, length per unit volume and mean transverse sectional area. PCNA indices were determined by estimating the percentage frequency of PCNA positive nuclei in basal and spinous strata. Generally, there were significant increases in all PCNA indices and blood vessel parameters between the N group and the different pathological lesions. A highly positive correlation was detected between all PCNA indices and blood vessel parameters. These data suggest that increased vascularity and angiogenesis occur in support of actively proliferating and transforming oral epithelial cells in order to permit growth. PCNA indices and blood vessel parameters may have a potential application as diagnostic and prognostic indicators.

Adolescent↗

PubMed1995

A quantitative investigation of immunocytochemically stained blood vessels in normal, benign, premalignant and malignant human oral cheek epithelium.

The present study was designed to determine whether increased vascularity occurs during malignant transformation of human oral cheek epithelium. Nine normal (N) samples were taken from the resection margins of benign lesions; the pathological lesions were classified as chronic inflammation (CI; n = 11), fibrous hyperplasia (FH; n = 12), lichen planus (LIP; n = 8), dysplasia (DYS; n = 5), squamous cell carcinoma (SCC; n = 25; well differentiated [SCCWD]; n = 10; moderately to poorly differentiated [SCCMPD]; n = 15) and epithelium adjacent to carcinomas (EAC; n = 6). Sections were stained with monoclonal antibody (mAb) against vimentin using an ABC immunoperoxidase technique. All blood vessels present within a depth of 0.9 mm of lamina propria were quantified irrespective of their morphology. The blood vessel parameters quantified were volume density (VVBV, CT), number per unit area (NABV, CT), length per unit volume (LVBV, CT) and mean transverse sectional area (ABV). VVBV, CT increased significantly between normal and all pathological groups. Amongst the pathological groups, statistical differences were detected between CI and SCC, CI and EAC, FH and SCCWD, FH and EAC, LIP and SCC, LIP and EAC, DYS and SCCWD and DYS and EAC. The EAC group had the highest VVBV, CT and the values of NABV, CT and LVBV, CT were significantly higher in all the pathological groups when compared with the normal group. No significant differences were detected between any of the pathological group. The parameter ABV increased significantly between normal and DYS, FH, SCC, EAC, FH and EAC, FH and SCC, CI and EAC, CI and SCC, LIP and EAC and LIP and SCC. Spearman rank correlations detected a positive correlation between the severity of oral lesions and all of the blood vessel parameters. We conclude that a mAb against vimentin improved the identification of smaller blood vessels and the blood vessel data suggest that angiogenesis occurs in premalignant and malignant lesions of human oral cheek epithelium. Angiogenesis seems to play an essential role in sustaining the actively growing and transforming cells.

Adolescent↗

PubMed1995

Blood vessel morphometry in human colorectal lesions.

Neovascularisation in tumours of different cell origins has been well documented qualitatively. In this report, we have assessed vascular architecture in different pathological lesions of the colorectum by quantifying blood vessel parameters in order to detect subtle morphological changes using objective methods. Colorectal tissue samples were obtained from resected large bowels containing malignant tumours. Biopsies were taken from defined sites in the resected specimen and were classified as normal (N), potentially premalignant mucosa (PPM), adenomatous polyp (P) and adenocarcinoma (ADCA). All tissues were fixed in modified Karnovsky's fixative for 4 hrs and postfixed in 1% OsO4 for 1 hr. Samples were processed for EM under standardized procedures and embedded in Epon. 0.5 microns semithin sections from five patients per group were stained with toluidine blue. A multistage systematic sampling procedure was adopted. The inner outlines of all blood vessels in the lamina propria (LP) were digitised using a Zeiss VIDAS Image Analyzer at a final magnification of x1,050. The area of the reference (LP) was also measured. No attempt was made to distinguish between the different types of vessel. The morphometric blood vessels parameters quantified were volume density (Vv), numerical density (NA), length density (LV) and mean transverse sectional area (A). Statistically significant differences in Vv and A were detected between all groups except between N and PPM and between P and ADCA. No significant differences in NA and LV were present in any group comparisons. The mean values of all parameters were the highest in ADCA.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenocarcinoma↗

PubMed1992

A morphometric study of histological variations during cellular differentiation of normal human colorectal epithelium.

Quantifiable variations existing in the colorectal crypt during cellular differentiation were detected by using simple computer-aided morphometric techniques applied to routinely prepared H&E stained and semithin toluidine blue stained sections of normal colonic mucosa. Generally, most of the morphometric parameters including nuclear volume, nuclear volume weighted mean volume, cytoplasmic volume, cellular volume, nuclear axial ratio (a/b), mean nuclear diameter, nuclear shape factor (NSF) and nuclear maximum angle (Agmax) showed an increasing trend between basal and surface segments. Conversely, the nuclear-cytoplasmic (N/C) ratio, NSF and nuclear circularity index (NCI) decreased between these segments. Epithelial cells in the basal segment had the highest N/C ratio and the lowest cell volume due to their low volumes of cytoplasm. However, substantial increases of cytoplasmic volume occurred in the intermediate segment, thereby expanding the cell volume to 136% of that of the basal segment cell. Data for a/b, NSF, NCI and Agmax suggest that the epithelial nuclei were more ellipsoidal in shape and were aligned more perpendicular to the basement membrane as they reached the surface epithelium. Numerical densities for epithelial cell nuclei were highest in the basal segment, indicating more nuclear profiles at this region per unit area or volume. This also suggested that the basal segment was the active proliferating zone. Such observations agree with previously reported cell kinetic and autoradiographic studies.

Aged↗