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PubMed1998

Validity of the specialized columnar epithelium as a diagnostic criterion of the short segment Barrett's esophagus.

OBJECTIVE: In the areas where intestinal metaplasia of the stomach is highly prevalent, diagnosing Barrett's esophagus solely by the presence of specialized columnar epithelium in the distal esophagus may lead to many false positive diagnoses. The aim of this study was to test validity of the specialized columnar epithelium as a diagnostic criterion of the short segment Barrett's esophagus in Korea. METHODS: During routine gastroscopy, the length of columnar-lined esophagus was measured and biopsy samples were taken from the mucosa immediately distal to the squamocolumnar junction. Under light microscopy, alcian blue-positive cells were identified. RESULTS: Prevalence of the specialized columnar epithelium in cases without the columnar-lined esophagus and with the short segment columnar-lined esophagus were 57.1% and 31.2%, respectively (P = 0.0281). The specialized columnar epithelium is frequently seen around the cardia in Koreans with or without the columnar-lined esophagus. CONCLUSION: Simple presence of the specialized columnar epithelium is not a valid criterion for a diagnosis of Barrett's esophagus. We propose that both the short segment Barrett's esophagus and the goblet cell metaplasia of the cardia might be grouped together under a title of "the specialized columnar epithelium around the gastroesophageal junction" as a potential preceding condition of adenocarcinoma around the cardia.

Adult↗
PubMed1999

The relative amount of epithelium, muscle, connective tissue and lumen in prostatic hyperplasia as a function of the mass of tissue resected.

PURPOSE: The relative amounts of epithelium, connective tissue, muscle and gland lumen in benign prostatic hyperplasia have been reported but they have not been correlated with prostate size. We determine if the relative amount of prostatic tissue varies with prostate size. MATERIALS AND METHODS: Paraffin blocks of transurethrally resected prostate tissue were randomly chosen from the archives of 58 patients with benign prostatic hyperplasia. Two new slides per patient were made and stained with prostate specific antigen or Masson trichrome, respectively. A total of 20 images from each slide were captured using a high resolution camera, digitized and analyzed with computer software for the relative percentage of the various tissue components. RESULTS: As the amount of prostate tissue resected increased from less than 10 to greater than 70 gm. the epithelium had a 4-fold increase from 5.37 to 21.92%, the muscle component had a 42% decrease from 28.46 to 16.62%, the lumen doubled from 7.05 to 14.01% and the connective tissue remained relatively unchanged from 35.58 to 31.53%. There was a statistically significant difference in all components of prostatic tissue except for connective tissue when comparing prostates less than 30 versus greater than 30 gm., including epithelium 6.52 versus 16.10% (p <0.01), muscle 28.45 versus 20.78% (p <0.01), lumen 7.42 versus 14.58% (p <0.01) and connective tissue 35.74 versus 32.45% (p <0.06). The stroma-to-epithelium and muscle-to-epithelium ratios each had a 9-fold decline (p = 0.01). CONCLUSIONS: As the prostate increases in size, there is statistically significant more epithelium and lumen, and less muscle tissue.

Connective Tissue↗
PubMed1999

Osmotic regulation of airway reactivity by epithelium.

Inhalation of nonisotonic solutions can elicit pulmonary obstruction in asthmatic airways. We evaluated the hypothesis that the respiratory epithelium is involved in responses of the airways to nonisotonic solutions using the guinea pig isolated, perfused trachea preparation to restrict applied agents to the mucosal (intraluminal) or serosal (extraluminal) surface of the airway. In methacholine-contracted tracheae, intraluminally applied NaCl or KCl equipotently caused relaxation that was unaffected by the cyclo-oxygenase inhibitor, indomethacin, but was attenuated by removal of the epithelium and Na+ and Cl- channel blockers. Na+-K+-2Cl- cotransporter and nitric oxide synthase blockers caused a slight inhibition of relaxation, whereas Na+,K+-pump inhibition produced a small potentiation. Intraluminal hyperosmolar KCl and NaCl inhibited contractions in response to intra- or extraluminally applied methacholine, as well as neurogenic cholinergic contractions elicited with electric field stimulation (+/- indomethacin). Extraluminally applied NaCl and KCl elicited epithelium-dependent relaxation (which for KCl was followed by contraction). In contrast to the effects of hyperosmolarity, intraluminal hypo-osmolarity caused papaverine-inhibitable contractions (+/- epithelium). These findings suggest that the epithelium is an osmotic sensor which, through the release of epithelium-derived relaxing factor, can regulate airway diameter by modulating smooth muscle responsiveness and excitatory neurotransmission.

Animals↗
PubMed1998

[The role of lens epithelium in cataract formation in diabetic rats].

This study was designed to evaluate the changes and the role of lens epithelium in sugar cataract formation, in regard to the fact that the highest level of aldose reductase is found in this layer of lens. By light and electron microscopy, we examined the histological changes of central epithelium in lens of rats made diabetic with streptozotocin (STZ) with or without AL1576, an aldose reductase inhibitor, at varying periods of time ranging from 5 to 40 days after intraperitoneal injection of STZ. Also, we examined Na-K-ATPase activity in lens epithelium of rats with diabetes, diabetes plus AL1576 and normal controls at the time of 30 days. The results showed that the first detectable abnormalities occurred after 15 days of STZ injection and were limited to the lens epithelium; cell edema, intracellular vacuoles and extention of rough endoplasmic reticulum pool were remarkable; that AL1576 could prevent almost all of the lesion mentioned above; and that Na-K-ATPase activity in lens epithelium of rats with diabetes increased at the time of 30 days. The findings suggest that lens epithelium may play an important role in sugar cataractogenesis.

Aldehyde Reductase↗
PubMed2000

Effect of ozone treatment on airway reactivity and epithelium-derived relaxing factor in guinea pigs.

Ozone (O(3)) is toxic to respiratory epithelium and causes airway inflammation and hyperreactivity. To evaluate the role of the epithelium in the development of hyperreactivity, we examined in guinea pigs the effects of inhaled O(3) (3 ppm for 1 h; 0-24 h after exposure) on 1) reactivity to inhaled methacholine (MCh), 2) reactivity of the isolated, perfused trachea (IPT) to MCh, 3) epithelium-derived relaxing factor (EpDRF)-mediated relaxations of IPT induced by mucosal hyperosmolar solutions, 4) neurogenic contraction and relaxation responses, 5) transepithelial potential difference, and 6) microscopic analysis of nitrotyrosine immunofluorescence, substance P fiber density, and tracheal morphology. At 0 h, O(3) caused hyperreactivity to inhaled MCh and mucosally but not serosally applied MCh in IPT (only in the presence of the epithelium) and a decrease in transepithelial potential difference. Inhibition of EpDRF-induced relaxation responses occurred at 2 h. All of these changes returned to control by 12 to 18 h. O(3) had no effect on neurogenic responses. Nitrotyrosine immunofluorescence appeared in the trachea at 0 h in detached epithelial cell ghosts and in intrapulmonary airways by 6 h. Substance P fiber density was elevated in smooth muscle at 0 and 18 h but not in epithelium or lamina propria of intrapulmonary and extrapulmonary bronchi. Loss of cilia and mucosubstances in the mucosa occurred at 0 h; the epithelium became markedly attenuated over 12 to 24 h. A reversible increase in epithelial permeability and a decrease in EpDRF production may contribute to O(3)-induced hyperreactivity to MCh.

Animals↗
PubMed2000

The role of NaKCl cotransport in blood-to-aqueous chloride fluxes across rabbit ciliary epithelium.

PURPOSE: To evaluate the role of NaKCl cotransport in short-circuit current (Isc) and chloride fluxes across rabbit ciliary epithelium mounted in a Ussing-type chamber. METHODS: Bilayered intact ciliary epithelium free of stroma was obtained after perfusion and dissection of rabbit eyes and mounted in an Ussing-type chamber. The effects of bumetanide and other drugs on Isc and transepithelial 36Cl fluxes in bicarbonate-containing Ringer's were determined. Immunoblot analysis was performed by standard techniques. RESULTS: Bumetanide (100 microM) applied to the blood (pigmented epithelium [PE]) side of the ciliary bilayer caused a dose-dependent decrease in Isc from 18.2 +/- 2.2 to 10.4 +/- 1.4 microA/cm2 (43%). Bumetanide applied to the aqueous (nonpigmented epithelium [NPE]) side of the tissue inhibited Isc by only 12%. Immunoblots of dissected NPE and PE tissue probed with an antibody to mammalian NaKCl cotransporter detected approximately 10 times more NaKCl cotransporter protein in PE than in NPE. 36Cl flux studies revealed a PE-to-NPE chloride flux of 180.3 +/- 37.2 microEq/cm2 per hour and an NPE-to-PE flux of 72.3 +/- 22.9 microEq/cm2 per hour, indicating a net PE-to-NPE flux of 108.0 +/- 31.3 microEq/cm2 per hour across rabbit ciliary epithelium. Bumetanide inhibited the PE-to-NPE chloride flux by 52% but did not inhibit the NPE-to-PE flux. Isoproterenol (10 microM) added to the PE side of the bilayer increased Isc by a dose-dependent 53%. Prior addition of bumetanide to the PE side blocked the increase due to isoproterenol by 37%. Isoproterenol (10 microM) stimulated the PE-to-NPE chloride flux by 75% but had no stimulatory effect on the NPE-to-PE chloride flux. 4,4'Diisothiocyanatostilbene-2,2'disulfonic acid (DIDS) inhibited Isc when added to either side of the bilayer but was more potent at low concentrations (<100 microM) when added to the NPE side and more potent at higher concentrations (>100 microM) when added to the PE side. Prior addition of 1 mM DIDS to the NPE side decreased isoproterenol stimulation of Isc by 56%. CONCLUSIONS: NaKCl cotransporters located primarily on the blood side of rabbit ciliary epithelium contribute to aqueous-negative Isc and to blood-to-aqueous chloride transport across the tissue in bicarbonate-containing medium. DIDS-inhibitable mechanisms, possibly including HCO3-Cl exchange and Cl channels, also play a role. Isoproterenol stimulation of Isc involves coordinate upregulation of PE-side NaKCl cotransport and an NPE-side DIDS-inhibitable mechanism(s).

4,4'-Diisothiocyanostilbene-2,2'-Disulfonic Acid↗
PubMed2001

Expression studies and mutational analysis of the androgen regulated homeobox gene NKX3.1 in benign and malignant prostate epithelium.

PURPOSE: The NKX-3.1gene is an androgen regulated prostate specific homeobox gene that is believed to have a vital role in normal prostate development. In mice the homologue NKx3.1 is exclusively expressed in prostate epithelium. In humans NKX3.1 expression is also restricted to the prostate but to our knowledge the cellular location has not been described. Furthermore, since NKX3.1 maps to chromosomal band 8p21, a region with high loss of heterozygosity in prostate cancer, the gene has been proposed to have tumor suppressor function. In this study we demonstrate that in human prostates NKX3.1 is expressed exclusively in secretory epithelial cells and the level of NKX3.1 expression remains invariant in normal tissue and in tissue showing various grades of prostate cancer. In the 19 cases examined the DNA sequences of the NKX3.1 gene were identical and no mutation was detected. MATERIALS AND METHODS: Frozen tissue from patients who underwent radical prostatectomy was used for this study. For in situ hybridization experiments a 377 bp fragment corresponding to a portion of the 3' untranslated region of the NKX3.1 gene was amplified by polymerase chain reaction and cloned into the pCRII plasmid vector Invitrogen. Antisense or sense [33P] uridine triphosphate labeled RNA probes were generated with SP6 or T7 RNA polymerase and hybridized to the tissue sections. Slides were exposed to photographic emulsion and visualized on autoradiography. Laser capture microdissection was performed to procure pure populations of malignant epithelium. DNA was isolated by digesting samples in proteinase K buffer. Polymerase chain reaction and direct sequencing was performed using standard protocols. RESULTS: In vitro hybridization showed that NKX3.1 expression was restricted to secretory epithelial cells within benign prostate glands. No expression was detected in stroma or infiltrating lymphocytes. NKX3.1 was expressed in all grades of malignant epithelium in all 25 cases examined. Direct sequencing of the coding region of NKX3.1 revealed the wild-type sequence in all 18 microdissected cancers analyzed. CONCLUSIONS: Based on our studies we propose that NKX3.1 gene expression is restricted to benign and malignant secretory epithelium within the prostate but NKX3.1 does not appear to be a classic tumor suppressor gene responsible for prostate cancer initiation. These findings are consistent with the role of NKX3.1 in the development of normal prostate epithelium and maintenance of normal secretory function. Thus, NKX3.1 may represent a useful molecular marker for benign and malignant prostate epithelium.

DNA Mutational Analysis↗
PubMed2002

Involvement of p27(KIP1) degradation by Skp2 in the regulation of proliferation in response to wounding of corneal epithelium.

PURPOSE: To examine the expression of the p27(KIP1)in the normal and epithelial-scraped cornea and whether degradation of p27(KIP1)by Skp2 is involved in the regulation of cell proliferation in response to wounding of the corneal epithelium. METHODS: C57Bl6, p27(KIP1-/-), Skp2(-/-), and Skp2(-/-)/p27(KIP1-/-) double-knockout mice were examined. Normal and epithelial-scraped corneas were analyzed by immunocytochemistry using anti-p27(KIP1) antibody. Cells in the S phase of DNA synthesis were analyzed by immunocytochemistry using anti-bromodeoxyuridine (BrdU) antibody. RESULTS: The p27(KIP1) was expressed in basal cells of the central and peripheral region of the cornea and limbus. This expression was not detected 24 hours after the epithelial scraping, when there were many cells in the S phase of DNA synthesis in the corneal epithelium. There were no obvious differences in the thickness and anti-BrdU staining in the corneal epithelium of p27(KIP1-/-) mice from that of control animals. Twenty-four hours after epithelial scraping in the Skp2(-/-) mice, the corneal epithelium was thinner than in wild-type mice and had many p27(KIP1)-positive cells and few BrdU-positive cells. In contrast, 24 hours after epithelial scraping in the Skp2(-/-)/p27(KIP1)(-/-) double-knockout mice, the corneal epithelium was as thick as in wild-type mice and had many BrdU-positive cells. CONCLUSIONS: These results suggest that degradation of p27(KIP1) by Skp2 is involved in the regulation of cell proliferation in response to wounding of the corneal epithelium.

Animals↗
PubMed2002

[Mode of epithelium-fibroblast interaction in mixed heterotypic cell cultures].

The interaction between epithelium (dog kidney epithelium MDCJ/clone 20) and fibroblasts (diploid human fibroblasts M19 and AG-1523) was studied in mixed heterotypic cell cultures. The mode of cell interaction depends on the manner of their collision. At collision of the epithelium lamella and the lateral side of fibroblast, the lamella was seen to creep under the lateral side to force back the fibroblast. At the frontal collision of epithelium and fibroblast lamellae, the mode of interaction depends on the local situation. With the presence of a free substratum around, the fibroblast formed a new lamella and moved aside from the place of collision. In the case, when the neighboring cells prevented fibroblast from moving, it migrated under the epithelium. In this work, we have first demonstrated the formation of specialized intercellular adhesions between epithelium and fibroblasts. The cultures were studied by phase contrast, interference reflection or video tape recording, using an image processing system (Hamamatsu). For studying adhesion, immuno-fluorescent methods were performed.

Animals↗
PubMed1975

[The development of differentiation of pigment epithelium in teleosts and its stimulation to metaplasia].

The time was determined when pigmented epithelium acquires stable differentiation and the possibility was investigated for pigmented epithelium to transform in retina at different developmental stages in the Issyk-kul chebatchok Leuciscus bergi (Cyprinidae). By means of implantation of a layer of pigmented epithelium in pericardium it was established that the pigmented epithelium cells acquired stable differentiation rather early. When an already pigmented layer of pigmented epithelium was implanted in the cavity of a lensless eye, its cell transformed in retina under the influence of the whole retina. Conditions of pigmented epithelium metaplasia in retina in teleosteans proved to be similar with those for frogs.

Animals↗
PubMed1975

[The ultrastructure of the rat esophageal epithelium during ontogenesis].

The development of the epithelium of the rat esophagus was examined continuously from the 13th day post-conception until one day post-partum. Besides the single-results at different phases of development the knowledge, that the esophageal ontogeny of different mammalians may be considerably different, is of special importance. To this matter of fact was not paid attention in present literature, but the authors accentuate common things. The significant results during development are the following: 1. The completely undifferentiated epithelium of the 13th day at the same time develops basement-membrane and basic membrane of the cytoplasm. The organelles are under construction. Centriols in cells near to the lumen are seen in connection to the single-cilia, which occur till the 17th day of ontogeny. These essentially differ from cilia of the ciliated epithelium. 2. The cylindrical epithelium constitutes until the 16th day. Afterwards the first synthetic productivity like organisation of filaments are observed. By that superficial cells loose their capacity to divide. 3. On the 17th day intercellular spaces between neighbouring cells at the lumen abruptly rip up. In loco cylindrical cells change to squamous cells. There are no essential differences in time between cranial and caudal parts of the esophagus which proofs an entodermal genesis of the epithelium. 4. Changes in the ultrastructure at about 19 days p.c. cause the epithelium's keratinization. 5. 21 days p.c. few cilia-bearing cells scattered between the cells in keratinization are to be seen. 6. Before birth superficial cells become separated and are shed from the surface completely post-partum.

Animals↗
PubMed1992

The influence of cyclic AMP upon Na,K-ATPase activity in rabbit ciliary epithelium.

ATPase activity was measured in samples of freshly dissected rabbit ciliary epithelium. The epithelium was ruptured in distilled water, frozen briefly, and incubated at 37 degrees C in a buffer containing 100 mM NaCl and 32P-labeled adenosine triphosphate (ATP). The rate of ATP hydrolysis by the epithelium was linear for as long as 45 min. Ouabain (1 mM) reduced the ATP hydrolysis rate by approximately 50%. When the epithelium was preincubated for 10 min. in the presence of 1 mM dibutyryl cyclic adenosine monophosphate (cAMP), the ouabain-sensitive (Na,K-ATPase) activity was diminished; ouabain-insensitive ATPase activity was not reduced. Preincubation of the epithelium with forskolin with isobutylmethylxanthine also reduced ouabain-sensitive ATPase activity. These observations suggest that the ciliary epithelium may have a mechanism for short-term modulation of Na,K-ATPase activity by cAMP. Such a mechanism could be linked to the ability of cAMP-dependent protein kinase to reduce Na,K-ATPase activity in the tissue.

Adenosine Triphosphate↗
PubMed2005

[Proliferation of corneal epithelium and apoptosis of keratocytes in the rabbit cornea after treatment with 20% ethanol].

OBJECTIVE: To study the proliferation activity of corneal epithelial cells and the apoptosis of keratocytes in the rabbit cornea after treatment with 20% ethanol. The results were compared to the cornea treated with mechanical scraping of the epithelial cells. METHODS: The experimental group consisted of 42 rabbits. One of the two corneas of each rabbit was incised by 8 mm epithelial trephine using in LASEK and was exposed to 20% ethanol (in distilled water) in the trephine for 40 seconds. In the other eye, the corneal epithelium in the central area was mechanically scraped. The rabbits in the experimental group were randomly divided into seven sub-groups. Each sub-group had six rabbits and the rabbits were killed at 0, 4 hours, 1, 3, 5, 8 and 30 days after the surgery. Three rabbits without any treatment were used as blank controls. Immunohistochemical staining (Ki-67 antigen) was performed to detect the proliferation of corneal epithelial cells. Apoptotic cells were detected by TUNEL assay. Number of keratocytes in the central anterior stroma of cornea was determined by counting the total number of cells under 400 x magnification field in hematoxylin-eosin-stained corneal sections. RESULTS: In the ethanol-treated eyes, the number of Ki-67 positive cells peaked 5 days after the treatment in the central corneal epithelium and 1 day after the treatment in the peripheral corneal epithelium. TUNEL-positive cells were detected in the anterior central stromal keratocytes under the epithelial incisions and the number of TUNEL-positive cells reached a peak 4 hours after the treatment. There was no statistically significant difference in the number of central anterior stromal keratocytes between the ethanol-treated group and the controls (P = 0.68). In the mechanical scraping group, the number of Ki-67 positive cells in the peripheral corneal epithelium peaked 3 days after the treatment. The number of Ki-67 positive cells in the peripheral corneal epithelium of the scraping group was greater than that of the ethanol-treated group. TUNEL-positive cells were detected in the anterior central stromal keratocytes and reached a peak 4 hours after the scraping. The number of central anterior stromal keratocytes was decreased maximally 1 day after the scraping (P < 0.01). CONCLUSIONS: The cornea injury caused by treatment with 20% ethanol for 40 seconds is milder than that caused by mechanical scraping. The wound-healing process in the ethanol-treated cornea is faster than that of the cornea treated with scraping. Corneal epithelium treated with 20% ethanol for 40 seconds can protect the stromal keratocytes.

Animals↗
PubMedDate not supplied

[Morphofunctional changes in the bronchial epithelium in combined therapy for lung cancer].

Morphofunctional changes in the bronchial mucosa were studied in 33 patients with stage 3 lung cancer. The patients underwent intraoperative radiation therapy (IORT) in a dose of 15 Gy, using cisplatine as a radiosensitizer. No degenerative changes in the bronchial epithelium were found 2 weeks after IORT. Basal cell proliferation was observed, goblet cells were reduced in size and the basement membrane was thickened and twisted. Epithelial reparation due to pronounced local basal cell proliferation was observed 3 months later. A year later, the mucosa was covered with the multinuclear cylindrical epithelium and the cover of ciliated cells was preserved. The functional activity of goblet cells was in the normal range and scanty lymphoplasmocytic infiltration was found in the stroma. With IORT without radiosensitization, the damaged epithelium was regenerated due to the reserved cells coming from the damaged margins with the formation of an epidermoid regenerative layer and subsequent cell differentiation. Moderate sclerosis occurred in the stroma. A year later the bronchial epithelium was characterized by moderate goblet cell hyperplasia with preserved functional activity. Thus, IORT caused mucosal damage as alteration, dystrophy, and desquamation of the epithelium. Subsequently, the bronchial epithelium recovered through reparative regeneration.

Bronchi↗
PubMed1990

Expression of the 55-kD/64-kD corneal keratins in ocular surface epithelium.

According to the concept of keratin pairing defined by tissue coexpression, a 55-kD/64-kD keratin pair is a marker of "corneal-type" differentiation. Intermediate filament (IF)-enriched preparations from guinea pig and bovine corneal epithelium were analyzed, and a rabbit antiserum was generated against a 55-kD polypeptide enriched in these preparations. This antiserum generated a typical IF-like pattern in cultured bovine corneal epithelial cells. Immunofluorescence microscopic analysis of frozen sections of guinea pig and bovine tissue revealed that the 55-kD antiserum labeled corneal and limbal epithelium. In addition, the antiserum stained a subpopulation of peripheral limbal cells that were distributed in both basal and suprabasal layers of the epithelium. The monoclonal antibody AE5 was used to investigate the distribution of the 64-kD polypeptide in guinea pig and bovine tissue. Immunoblotting analysis revealed that AE5 antibodies recognized a 64-kD polypeptide in guinea pig cornea, but recognized a 66-kD polypeptide in bovine cornea. Immunofluorescence microscopic analysis of guinea pig tissue revealed that AE5 antibodies labeled suprabasal layers of corneal epithelium, in suprabasal layers of limbal epithelium, and in groups of cells in the peripheral limbal epithelium. We discuss the possibility that the ocular epithelial cells recognized by either the 55-kD or the 64-kD antibodies in the peripheral limbus may play a role in the reepithelialization of the cornea after wounding.

Animals↗
PubMed2005

Effect of death-to-preservation time on donor corneal epithelium.

PURPOSE: Surface disease is one of multiple variables affecting the quality of the postkeratoplasty donor cornea. Trauma to Bowman's layer before and during harvesting can denude the donor epithelium and result in epithelial defects in the donor following penetrating keratoplasty. Eye banks use death-to-preservation (DP) time intervals as long as 18 hours. This study evaluates the effects of higher DP time on the donor epithelium in storage medium and immediately following keratoplasty. METHODS: Eighty-one consecutive corneas were procured by the University of Kentucky Eye Bank, rated by one technician (H.W.), and used by one surgeon (W.S.V.) for elective penetrating keratoplasty. Donor records were retrospectively reviewed for age, DP time, and epithelial condition. All corneas were harvested and evaluated according to Eye Bank Association of America standards. Donor charts were reviewed for DP time and for condition of the epithelium in storage. Recipient charts were reviewed for epithelial defects following keratoplasty. RESULTS: Average DP time of all 81 donor corneas was 6:18 hours (ie, 6 hours, 18 minutes). Average DP time of 13 corneas with epithelial sloughing was 7:02 (range, 2:01 to 12:25) hours, and nine (69%) had DP time longer than 6 hours. Average DP time of 68 corneas with no sloughing was 6:09 (range, 1:59 to 11:03) hours (P < .32). Average DP of 28 recipients with epithelial defect on day 1 was 8:01 (range, 3:41 to 12:49), and average DP in 53 patients with an intact epithelium on day 1 was 5:23 (range, 1:59 to 9:46) (P < .001). The percentage of postoperative patients with epithelial defects in the graft on day 1 rose from 14% when DP was less than 4 hours to 100% when DP was greater than 10 hours. Average DP in 13 donors under age 30 was 8.3 hours. CONCLUSION: DP time longer than 6 hours was more likely to result in sloughing of the donor epithelium. Care of donor epithelium prior to harvesting becomes increasingly important with DP times longer than 6 hours. Higher-than-average DP times occurred in donors under 30 years of age. Higher DP time results in an increasing likelihood of epithelial defects in the graft. Donor corneas with lower DP time may be important in penetrating keratoplasty ocular surface disease.

Adolescent↗
PubMed2006

Molecular profiles of the mouse postnatal development of the esophageal epithelium showing delayed growth start.

Studies on molecular mechanisms of self-renewal in normal stem cells are required for understanding the cancer stem cell. Self-renewal in many kinds of normal stem cells might be accelerated in the growth of a young organism and in the repair of damaged tissue. This study examined whether the esophagus in growing neonates provides an experimental system for studies on epithelial stem cell renewal. The esophageal epithelium consists of 3 layers, from the luminal side to the bottom: the differentiated, epibasal and basal cell layers. The basal cell layer is known to contain the stem cells for the esophageal epithelium. This basic architecture is observed both in mice and humans. We investigated the basal cells in the mouse neonate by immunostaining with a basal cell marker, nerve growth factor receptor (Ngfr), and compared the basal cell content in the esophageal epithelium between mice and humans. A mouse esophageal epithelial cell primary culture system was developed for studies on the basal cell growth and keratinocyte differentiation, and microarray analysis was conducted for obtaining expression profiles of the basal cells. It was revealed that the growth of the esophageal epithelium begins from postnatal day 3, and that the timing is consistent with membrane localization of Ngfr in the basal cell. An increase in the basal cell number by Ngf treatment is observed in in vitro mouse esophageal epithelium cultures. Furthermore, mRNA overexpression of Pdgfrb encoding platelet derived growth factor receptor beta and Egfr encoding epidermal growth factor receptor is associated with the timing of the growth of the esophageal epithelium in the neonatal mice. This study provides a new experimental model for studies on the growth of the basal cells, which are considered to include the stem cells, and on the enlargement of the body size in young organisms.

Animals↗
PubMed1990

Immunocytochemical detection of S-phase cells in normal and neoplastic cervical epithelium by anti-BrdU monoclonal antibody.

The use of a monoclonal antibody (MAb) to bromodeoxyuridine (BrdU) to identify S-phase cells was examined in 30 cervical biopsy specimens and 30 cervical smears from 18 patients with cervical neoplasia. Each patient received a local injection of 300 mg to 500 mg of BrdU into the cervix, at the time of endocervical laser conization, to label S-phase cells in neoplastic tissue. Labeled cells in normal and neoplastic tissues were detected in biopsy specimens or smears by indirect immunoperoxidase staining using the anti-BrdU MAb. The BrdU labeling index (BrdU LI, defined as the percentage of labeled cells in relation to the total number of cells counted) was calculated for all specimens. The level of BrdU-positive cells was 5.1% in normal cervical squamous epithelium, 12.3% in slight-to-moderate dysplasia and 21.2% in severe dysplasia to carcinoma in situ. In tissues without any dysplasia, BrdU-positive cells were mainly confined to the parabasal layer of the epithelium. In tissues showing slight-to-moderate dysplasia, BrdU-positive cells were mainly found in the lower half of the epithelium. BrdU-positive cells in severe dysplasia to carcinoma in situ were distributed throughout the full thickness of the epithelium. In addition, the few samples of squamous metaplasia and reserve cell hyperplasia encountered in this study exhibited a higher BrdU LI than did normal squamous epithelium. In cytologic specimens, BrdU-positive cells were found only in the cases of carcinoma in situ and in two cases containing normal cervical columnar epithelial cells. These results suggest that the immunocytochemical detection of BrdU by MAb staining may be useful for evaluating the proliferative activity in normal and neoplastic cervical epithelium.

Antibodies, Monoclonal↗