Robert S. Redman

Vitamin E in the treatment of chemotherapy-induced mucositis

PURPOSE To determine the efficacy of vitamin E in the treatment of chemotherapy-induced mucositis in patients with malignancy. PATIENTS AND METHODS A randomized, double-blind, placebo-controlled study was performed to evaluate the efficacy of topical vitamin E in the treatment of oral mucositis in patients receiving chemotherapy for various types of malignancy. A total of 18 patients, 17 of whom had solid tumors and one with acute leukemia, were included in this study. Lesions were observed daily prior to and 5 days after topical application of either vitamin E or placebo oil. RESULTS Six of nine patients receiving vitamin E had complete resolution of their oral lesions. In eight of nine patients who received placebo, complete resolution of their oral lesions was not observed. This difference is statistically significant (p = 0.025 by Fishers exact test). No toxicity was observed in this study. CONCLUSION These results suggest that vitamin E may be an effective therapy in patients with chemotherapy-induced mucositis.

Proinflammatory cytokines tumor necrosis factor-α and interferon-γ alter tight junction structure and function in the rat parotid gland Par-C10 cell line

Sjögrens syndrome (SS) is an autoimmune disorder characterized by inflammation and dysfunction of salivary glands, resulting in impaired secretory function. The production of the proinflammatory cytokines tumor necrosis factor-alpha (TNF-alpha) and interferon-gamma (IFN-gamma) is elevated in exocrine glands of patients with SS, although little is known about the effects of these cytokines on salivary epithelial cell functions necessary for saliva secretion, including tight junction (TJ) integrity and the establishment of transepithelial ion gradients. The present study demonstrates that chronic exposure of polarized rat parotid gland (Par-C10) epithelial cell monolayers to TNF-alpha and IFN-gamma decreases transepithelial resistance (TER) and anion secretion, as measured by changes in short-circuit current (I(sc)) induced by carbachol, a muscarinic cholinergic receptor agonist, or UTP, a P2Y(2) nucleotide receptor agonist. In contrast, TNF-alpha and IFN-gamma had no effect on agonist-induced increases in the intracellular calcium concentration [Ca(2+)](i) in Par-C10 cells. Furthermore, treatment of Par-C10 cell monolayers with TNF-alpha and IFN-gamma increased paracellular permeability to normally impermeant proteins, altered cell and TJ morphology, and downregulated the expression of the TJ protein, claudin-1, but not other TJ proteins expressed in Par-C10 cells. The decreases in TER, agonist-induced transepithelial anion secretion, and claudin-1 expression caused by TNF-alpha, but not IFN-gamma, were reversible by incubation of Par-C10 cell monolayers with cytokine-free medium for 24 h, indicating that IFN-gamma causes irreversible inhibition of cellular activities associated with fluid secretion in salivary glands. Our results suggest that cytokine production is an important contributor to secretory dysfunction in SS by disrupting TJ integrity of salivary epithelium.

Development and characterization of SV40 immortalized rat parotid acinar cell lines.

SummaryRat parotid salivary gland acinar cells were transfected by CaPO4 precipitation using a plasmid containing a replication-defective simian virus (SV40) genome. Out of 30 clonal cell lines, 2 were shown to have moderate to high levels of cytodifferentiation and salivary gland acinar cell function. Functional studies with the two cell lines indicated that the β-adrenergic agonist (isoproterenol), vasoactive intestinal peptide prostaglandin E1, and forskolin were effective activators of intracellular cyclic adenosine 3′:5′-cyclic monophosphate production. Phenylephrine, carbamylcholine, and UTP were effective in increasing inositol phosphate production and intracellular free calcium levels, whereas substance P was without affect. Utilizing indirect immunofluorescence analysis, both cell lines were shown to express the SV40 large T antigen. Electron microscopic evaluation documented moderate to high levels of cytodifferentiation with the maintenance of tripartite junctional complexes, cellular polarization, and presence of moderate amounts of secretory granules and rough endoplasmic reticulum. The two cell lines had doubling times of 22 and 36 h, respectively.

Development and characterization of SV40 immortalized rat submandibular acinar cell lines

SummaryRat submandibular salivary gland acinar cells were transfected by CaPO4 precipitation using a plasmid containing a replication-defective simian virus (SV40) genome. Out of 27 clonal cell lines, two were shown to have moderate to high levels of cytodifferentiation and salivary gland acinar cell function. Functional studies with the two cell lines indicated that the β-adrenergic agonist, isoproterenol, vasoactive intestinal peptide, and prostaglandin E1 were effective activators of intracellular cyclic AMP production. Epinephrine, norepinephrine, phenylephrine, acetylcholine, and P2U-purinoceptor agonists were effective in increasing inositol phosphate production and intracellular free calcium levels, whereas substance P was without effect. Utilizing indirect immunofluorescence analysis, both cell lines were shown to express glutamine/glutamic acid-rich proteins, a submandibular acinar cell specific secretory protein family. Electron microscopic evaluation documented the maintenance of tripartite junctional complexes, cellular polarization, and the presence of moderate amounts of secretory granules and rough endoplasmic reticulum. The two cell lines had doubling times of 25 h.

Dietary fructose exacerbates the cardiac abnormalities of copper deficiency in rats.

Copper deficiency has been shown to result in severe cardiovascular lesions in several species of animals. The principal carbohydrate in the copper-deficient diet most often used with rats is sucrose, which is known to have adverse effects on carbohydrate and lipid metabolism and thus may contribute to cardiovascular disorders. These observations prompted experiments in which starch and fructose were substituted for sucrose in a copper-deficient diet, to see if the effects of the copper deficiency might be modified. In the hearts from rats fed copper-deficient diets with fructose or sucrose, there was marked, mostly ventricular hypertrophy, and mild to severe myocardial inflammation, degeneration, and fibrosis. Aneurysm of the left ventricle and pericarditis also were common. Hearts from the starch, copper-deficient groups were much less hypertrophic, and very few were affected by myocardial inflammation, degeneration, or fibrosis. Defects of elastin or other structures were not observed in the aortas or pulmonary or coronary arteries of any specimens.

Peripheral ameloblastoma with unusual mitotic activity and conflicting evidence regarding histogenesis

Peripheral ameloblastoma is a rare extraosseous odontogenic tumor with histologic characteristics similar to those of the more common intraosseous ameloblastoma. However, the peripheral lesion usually does not exhibit the invasive and aggressive behavior of its intraosseous counterpart.‘-’ It is thought to originate from one of two sources: extraosseous remnants of the dental lamina,6*7 or the basal cell layer of the oral epithelium, which is believed to have odontogenic potential.2q3 The purpose of this report is to document an example of a peripheral ameloblastoma that was unusual in several ways: age of patient, site, bone resorption, mitotic activity, and connections with the epithelia of both the overlying mucosa and subjacent rests of the dental lamina. Microscopic examination of 20 other specimens of ameloblastoma, both central and peripheral, confirmed that mitotic activity is rare except in malignant ameloblastomas, and provided further insight into the roles of mucosal epithelium and rests of the dental lamina in the origin of the peripheral variety.

Short-term primary culture of acinar-intercalated duct complexes from rat submandibular glands.

SummaryAcinar-intercalated duct complexes dissociated from rat submandibular glands have been shown to be an excellent model for studying secretory responses of salivary gland components. However, they are functionally normal for only a few hours. We undertook a systematic manipulation of primary culture conditions in an attempt to extend the useful life of the complexes. The major modifications that were tested were increased oxygenation in increments to 95%; substitution of norepinephrine or carbamylcholine or both for isoproterenol in the medium; different sources of collagen for and addition of laminin, fibronectin and/or type IV collagen to the matrix gel; and varying the thickness of the collagen gel, richness of the cell suspension inoculate, and sources and concentrations of sera in the medium. Progress was monitored by light microscopic evaluation of routine sections of specimens until improved maintenance of acinar and other cells warranted carrying parallel cultures for biochemical, histochemical, and ultrastructural analyses. Best results were obtained with 90% O2, laminin in rat tail collagen gel, 10% fetal bovine serum, and 3 μM isoproterenol. Morphologically, there was good survival of acini and intercalated ducts after 1 d, with decreased acinar size being correlated with secretory response to the isoproterenol. Reorganization and considerable mitotic activity were seen at 2, 3, and 4 d, with most clusters of cells becoming much larger than the original complexes. During this period acinar cells steadily became less differentiated and their numbers decreased in proportion to intercalated duct or undifferentiated cells. However, there was good overall survival through 7 d. Biochemical analysis indicated that the cells were able to maintain significant biosynthetic activity for 4 d, with DNA, RNA, protein, and glycoprotein synthetic rates increasing over the culture period, but the secretory capacity of the cells diminished during the primary culture period, with mucin biosynthesis and secretion decreasing significantly after 1 d in culture.

Necrotizing sialometaplasia in a patient with Buerger's disease and Raynaud's phenomenon

This report describes a case of necrotizing sialometaplasia (NS) in a patient diagnosed as having Buergers disease with secondary Raynauds phenomenon. The danger of misdiagnosing NS as a malignant lesion is emphasized. Possible causal relationships between the patients medical condition and the lesion are discussed.

A rat parotid gland cell line, Par-C10, exhibits neurotransmitter-regulated transepithelial anion secretion

Because of the lack of salivary gland cell lines suitable for Ussing chamber studies, a recently established rat parotid acinar cell line, Par-C10, was grown on permeable supports and evaluated for development of transcellular resistance, polarization, and changes in short-circuit current (Isc) in response to relevant receptor agonists. Par-C10 cultures reached confluence in 3-4 days and developed transcellular resistance values of >/=2,000 Omega . cm2. Morphological examination revealed that Par-C10 cells grew as polarized monolayers exhibiting tripartite junctional complexes and the acinar cell-specific characteristic of secretory canaliculi. Par-C10 Isc was increased in response to muscarinic cholinergic and alpha- and beta-adrenergic agonists on the basolateral aspect of the cultures and to ATP and UTP (through P2Y2 nucleotide receptors) applied apically. Ion replacement and inhibitor studies indicated that anion secretion was the primary factor in agonist-stimulated Isc. RT-PCR, which confirmed the presence of P2Y2 nucleotide receptor mRNA in Par-C10 cells, also revealed the presence of mRNA for the cystic fibrosis transmembrane conductance regulator and ClC-2 Cl- channel proteins. These findings establish Par-C10 cells as the first cell line of salivary gland origin useful in transcellular ion secretion studies in Ussing chambers.Because of the lack of salivary gland cell lines suitable for Ussing chamber studies, a recently established rat parotid acinar cell line, Par-C10, was grown on permeable supports and evaluated for development of transcellular resistance, polarization, and changes in short-circuit current ( I sc) in response to relevant receptor agonists. Par-C10 cultures reached confluence in 3-4 days and developed transcellular resistance values of ≥2,000 Ω ⋅ cm2. Morphological examination revealed that Par-C10 cells grew as polarized monolayers exhibiting tripartite junctional complexes and the acinar cell-specific characteristic of secretory canaliculi. Par-C10 I sc was increased in response to muscarinic cholinergic and α- and β-adrenergic agonists on the basolateral aspect of the cultures and to ATP and UTP (through P2Y2 nucleotide receptors) applied apically. Ion replacement and inhibitor studies indicated that anion secretion was the primary factor in agonist-stimulated I sc. RT-PCR, which confirmed the presence of P2Y2 nucleotide receptor mRNA in Par-C10 cells, also revealed the presence of mRNA for the cystic fibrosis transmembrane conductance regulator and ClC-2 Cl- channel proteins. These findings establish Par-C10 cells as the first cell line of salivary gland origin useful in transcellular ion secretion studies in Ussing chambers.

Effects of dexamethasone, epidermal growth factor, and retinoic acid on rat submandibular acinar-intercalated duct complexes in primary culture

SummaryMature acini with attached segments of intercalated ducts were dissociated from the submandibular glands of rats and grown in primary culture on gels of reconstituted rat tail collagen. Screening evaluations indicated that the following new conditions promoted a substantial improvement in the survival of the cells as compared with our previously reported results: a) adding dexamethasone, epidermal growth factor, and retinoic acid to the medium, b) decreasing the fetal bovine serum in the medium to 1%; and c) adjusting the oxygen in the gas phase to 50%. A detailed evaluation, including light and electron microscopy and biochemical analysis, then provided the following observations. The acinar-ductal complexes enlarged throughout the 22-d culture period, and after 4d sheets comprised of a one- to two-cell thick layer of acinar cells spread among the complexes. Synthesis of mucin, and its secretion in response to norepinephrine or cAMP, dropped precipitously to very low levels after 2 d. However, synthesis of DNA, general proteins, and glycoproteins dropped only transiently after 2 d, rising to levels approaching those of freshly dissociated complexes by 22 d. These data indicate that a shift occurred from the synthesis of large quantities of secretory proteins and glycoproteins, especially mucins, during the first 2d in culture, to other materials thereafter. Overall, the new culture conditions resulted in substantial growth and survival of acinar cells through 22 d in primary culture, but the important acinar characteristic of the synthesis and secretion of mucins was essentially lost after 4 d.