Ultrastructural study of cultured human gingival fibroblasts exposed to endotoxin

Our current concept of periodontal disease is that some mediators found in the gingival sulcus are able to penetrate the epithelial barrier and produce tissue destruction in the periodontium. Endotoxin, one such mediator, recently has been the subject of considerable study. The purpose of this investigation was to substantiate the role of endotoxin in the pathogenesis of periodontal disease by ascertaining its action on cellular and subcellular components. In order to accomplish this, cultured human gingival fibroblasts were exposed to media containing either 300 micrograms/ml or 500 micrograms/ml of endotoxin and untreated medium for a period of 24 hours. Cells were harvested and prepared for electron microscopy by conventional methods. Electron microscopic examination revealed alterations in mitochondria, Golgi apparatus, lysosomal-like bodies, cytofilaments and plasma membrane. Relationship of these alterations to pathologic processes is discussed.

Effect of oral zinc supplements on growth, hormonal levels, and zinc in healthy short children

13 short children aged 7-13 years who had a retarded bone age and low hair zinc concentration (under 140 micrograms/g) were treated with oral zinc supplements for a year. There was a significant increase in the growth rate in the children whose hair zinc concentration increased. Growth hormone, testosterone and somatomedin C also increased after oral zinc supplementation. Data from 755 short healthy children who have attended our Growth Clinic are presented which describe their hair and serum zinc concentration at different ages. The data indicate a decline in hair zinc concentration after birth with a gradual increase at age 4-6 years, finally reaching adult normal levels after adolescence.

Manganese in infant formulas and learning disability

The concentration of manganese in the hair of normal newborn infants was found to increase significantly from 0.19 micrograms/g at birth to 0.965 micrograms/g at 6 weeks of age and 0.685 micrograms/g at 4 months when they were fed infant formula. There was an insignificant increase to 0.330 micrograms/g at age 4 months in breast-fed infants. After this age there was a slow decline in hair manganese to 0.268 micrograms/g in normal children at age 8 years and 0.434 in learning disabled (hyperactive) children. This is the third study reporting elevated hair manganese in learning disabled children.

Effect of growth hormone on hair, serum, and urine zinc in growth hormone-deficient children

The present study shows that growth hormone administration to 30 growth hormone-deficient children significantly increased their hair zinc concentration (147.0 +/- 31.9 micrograms/ml before, and 168.7 +/- 30.4 micrograms/g after) and decreased their urinary zinc excretion (514 +/- 170 micrograms/g creatine before and 353 +/- 162 micrograms/g creatinine after), suggesting a role for growth hormone in zinc metabolism in children. Since the increase in hair zinc was similar to that found with testosterone on human growth, we speculate that at least some of the anabolic effects of growth hormone and androgens are mediated through their effect on zinc metabolism.

Adenylate cyclase and exocytosis of membrane-coating granules in oral mucosa

Adenylate cyclase-cAMP system has been demonstrated to be important in the regulation of proliferation and growth of stratified squamous epithelium. This study was performed to localize adenylate cyclase in the oral mucosa of the rabbit and to study the effect of isoproterenol on exocytosis of membrane-coating granules. Cytochemical localization of adenylate cyclase revealed that the enzyme was on the cell membrane of some basal and parabasal cells, most upper spinous cells, and an occasional dense superficial cell. The specific distribution of this enzyme in the stratified squamous epithelium is deemed to be related to the regulation of cell proliferation in the basal and parabasal layers, and related to the exocytosis of membrane-coating granules in the upper spinous layer. Electron-microscopic morphometric quantification of membrane-coating granules showed that there was decreased concentration of membrane-coating granules in isoproterenol-treated animals, indicating there is an accelerated exocytosis of granules upon stimulation of the adenylate cyclase-cAMP system by isoproterenol.

Calcium oxalate deposition in the periodontium secondary to chronic renal failure

Deposition of calcium oxalate in the periodontium with accompanying bone loss and tooth resorption, occurred in a 55-year-old woman on long-term renal dialysis for end-stage renal disease. These deposits were birefringent upon examination with polarized light. Scanning electron microscopy of the deposits revealed clusters of sharply angular oblong and needlelike crystals. Microincineration followed by staining with alizarin red S was positive for calcium oxalate. X-ray diffraction studies of the crystals in the tissue specimen revealed a pattern identical to that of commercially prepared calcium oxalate monohydrate. It is postulated that pre-existing inflammatory periodontal disease may have provided the appropriate milieu for the deposition and precipitation of crystals. These deposits, acting as a foreign body, further intensified the inflammatory response, resulting in extensive alveolar bone loss and external tooth resorption.

Fluorometry of selenium in human hair, urine and blood. A single-tube process for submicrogram determination of selenium

This communication introduces a special lyophilization process for selenium determination by fluorometric methods. It permits a small sample volume, with several modifications including a single test tube process. Samples and standard are lyophilized first, then digested with nitric-perchloric acid mixture in a heated sand bath. Selenium is complexed with 2,3-diaminonaphthalene and extracted by n-hexane in the same test tube. The n-hexane layer is transferred to a cuvette and measured fluorometrically. Selenium concentration in healthy children from Long Island (aged 5-18 years) was: hair 0.765 +/- 0.114 microgram/g (n = 52), urine 28.65 +/- 8.27 micrograms/g creatinine (n = 66), and serum 95.4 +/- 14.4 ng/ml (n = 44). The current literature reflects an increase in the role of selenium in human nutrition. Thus, a simple but reliable method for determination of selenium in biological materials is needed in the clinical and research laboratory.

Zinc deficiency: improvement in growth and growth hormone levels with oral zinc therapy

A 14-year-old girl and a 13-year-old boy were found to be growth hormone deficient by insulin-arginine stimulation tests, and were also found to be zinc deficient. When oral zinc replacement was given, they both had a significant increase in growth rate which continued for at least 2 years, and subsequent growth hormone tests were normal.

Hyaline bodies in the connective tissue wall of odontogenic cysts

Hyaline bodies are sometimes encountered in the connective tissue wall of odontogenic cysts. In this study, various histomorphologic types of hyaline bodies were observed in a dentigerous cyst and a residual apical periodontal cyst. Some hyaline bodies appeared to be a coagulum of serum fluid surrounded by a small number of fibroblasts. Others appeared to be composed of fibrillar structures. Still others appeared to be a mixture of various amounts of serum coagulum and fibrillar structures. Immunoperoxidase procedures revealed various amounts of serum proteins in hyaline bodies. Gomori's trichrome stain and Mallory's staining technique showed that fibrillar structures were collagenous in nature. Electron microscopy showed that fibrillar structures were frayed collagen fibrils. These observations suggest that various histologic types of hyaline bodies represent different stages of development and that the basic pathogenic mechanism is pooling of extravasated serum followed by fibrosis.

Osteogenic sarcoma of the tongue

A 45-year-old woman had a mass in the left side of the tongue. Histologic examination of the tumor revealed it to be an extraskeletal osteogenic sarcoma. Pulmonary metastases were seen on admission. The patient had a rapid downhill course and died. Extraskeletal osteogenic sarcomas are well-recognized albeit rare neoplasms. In a search of the literature we were unable to find a single case arising in the tongue. The electron microscopic findings are also presented.

Zinc nutritional status, androgens, and growth retardation

Zinc levels were measured in hair and serum of boys with constitutional growth delay and familial short status and in several boys before and after oral administration of methyltestosterone. These results show the following: (1) zinc levels in boys beyond stage 3 of genital development are significantly higher than in stage 1 and 2; (2) there is a linear relationship between zinc levels and serum testosterone concentration (up to 250 ng/dL); and (3) methyltestosterone administration raised the zinc concentration in serum and hair, especially in boys with constitutional growth delay. Therefore, increased endogenous production or exogenous supply of testosterone are associated with increased zinc levels. We speculate that the relative testosterone deficiency and hypogonadotropism seen in constitutional growth delay may result in decreased zinc levels, which in turn could cause a further delay in the appearance of secondary sexual characteristics and greater growth retardation.

Canalicular adenoma of the upper lip: an electron microscopic study

Canalicular adenoma is composed of a row of tall columnar cells adjacent to canalicular lumina and a row of conical cells adjacent to connective tissue stroma. It differs from basal cell adenoma, of the parotid by the lack of well developed desmosomes associated with bundles of tonofilaments; by the presence of moderate numbers of cellorganelles; by a single, inconspicuous basal lamina instead of multi-layering; and by the presence of mucoid material in the stroma. Results suggest that this type of tumor should be considered a specific benign entity of the salivary glands. Cytologic features also suggest that it originates in excretory duct cells of minor salivary glands.

Folate analogues altered in the C9-N10 bridge region. 16. Synthesis and antifolate activity of 11-thiohomoaminopterin

The synthesis of 11-thiohomoaminopterin (1), which is a close analogue of 11-thiohomofolic acid (2), has been carried out by modification of the Boon-Leigh procedure. Treatment of 1-chloro-4-[p-(carbomethoxy)thiopenoxy]-2-butanone (5) with sodium azide gave 1-azido-4-[p-(carbomethoxy)thiophenoxy]-2-butanone (6). After protection of the carbonyl group of 6, the product 7 was catalytically hydrogenated to 1-amino-4-[p-(carbomethoxy)thiophenoxy]-2-butanone ketal (3). Reaction of 32 with 6-chloro-2,4-diaminmo-5-nitropyrimidine gave the desired pyrimidine intermediate, which was elaborated to 4-amino-4-deoxy-11-thiohomopteroic acid (20) by standard procedures. Alternately, 1-azido-4-[p-(carbomethoxy)thiophenoxy]-2-butanone ketal (7) was hydrolyzed to the corresponding acid (8) and coupled with diethyl L-glutamate to obtain diethyl N-[p-(1-azido-2-oxo-4-thiobutanoyl)benzoyl]-L-glutamate ketal (10), which was used for the large-scale preparation of 11-thiohomoaminopterin (1). Although 11-thiohomoaminopterin showed antifolate activity against two folate-requiring microorganisms and inhibited Lactobacillus casei dihydrogolate reductase, it did not exhibit any antitumor activity against L-1210 lymphoid leukemia in mice at a maximum dose of 48 mg/kg.

Studies of inhibition of rat spermidine synthase and spermine synthase

1. S-Adenosyl-l-methionine, S-adenosyl-l-homocysteine, 5'-methylthioadenosine and a number of analogues having changes in the base, sugar or amino acid portions of the molecule were tested as potential inhibitors of spermidine synthase and spermine synthase from rat ventral prostate. 2. S-Adenosyl-l-methionine was inhibitory to these reactions, as were other nucleosides containing a sulphonium centre. The most active of these were S-adenosyl-l-ethionine, S-adenosyl-4-methylthiobutyric acid, S-adenosyl-d-methionine and S-tubercidinylmethionine, which were all comparable in activity with S-adenosylmethionine itself, producing 70-98% inhibition at 1mm concentrations. Spermine synthase was somewhat more sensitive than spermidine synthase. 3. 5'-Methylthioadenosine, 5'-ethylthioadenosine and 5'-methylthiotubercidin were all powerful inhibitors of both enzymes, giving 50% inhibition of spermine synthase at 10-15mum and 50% inhibition of spermidine synthase at 30-45mum. 4. S-Adenosyl-l-homocysteine was a weak inhibitor of spermine synthase and practically inactive against spermidine synthase. Analogues of S-adenosylhomocysteine lacking either the carboxy or the amino group of the amino acid portion were somewhat more active, as were derivatives in which the ribose ring had been opened by oxidation. The sulphoxide and sulphone derivatives of decarboxylated S-adenosyl-l-homocysteine and the sulphone of S-adenosyl-l-homocysteine were quite potent inhibitors and were particularly active against spermidine synthase (giving 50% inhibition at 380, 50 and 20mum respectively). 5. These results are discussed in terms of the possible regulation of polyamine synthesis by endogenous nucleosides and the possible value of some of the inhibitory substances in experimental manipulations of polyamine concentrations. It is suggested that 5'-methylthiotubercidin and the sulphone of S-adenosylhomocysteine or of S-adenosyl-3-thiopropylamine may be particularly valuable in this respect.

Selenium in premature infants

Premature infants have a lower selenium concentration in serum than full-term infants and children. The selenium concentration goes down quickly in infants treated for respiratory distress syndrome without supplementation. One premature infant with bronchopulmonary dysplasia had persistently low concentrations of selenium. Vitamin E supplements did not affect the serum selenium concentration in healthy premature infants. Supplementation with 3 microgram/kg of selenium in parenteral fluids prevented the fall in the concentration seen in other infants not supplemented. Premature infants and especially those treated with oxygen may warrant selenium supplementation to the parenteral nutrition solution. Vitamin E supplements alone are apparently not sufficient to prevent selenium deficiency and potential oxygen toxicity.

Acid phosphatase in squamous cell carcinoma

Surgical specimens of oral squamous cell carcinoma were processed for cytochemistry of acid phosphatase using Gomori's substrate. Reaction product was deposited in the cytoplasmic dense bodies, autophagic vacuoles, cytoplasmic projections, and advancing cell borders. Results of this study suggest that acid phosphatase and its associated lysosomes seem to play a role in the invasiveness of cancer cells.

Focal epithelial hyperplasia in rabbit oral mucosa

Several papules on the floor of the mouth and the ventral surface of the tongue of a zinc-deficient rabbit were studied by light and electron microscopy. These papules appeared to be consistent with focal epithelial hyperplasia of man and chimpanzees. There was a concurrence of cytoplasmic vacuolization with the appearance of viral particles within the nucleus. Intranuclear crystalline viral aggregates were frequently observed in the upper spinous cells.

Folate analogues altered in the C9-N10 bridge region: 11-thiohomofolic acid

The synthesis of 11-thiohomofolic acid (2) has been accomplished by an unambiguous procedure. Reaction of 1-chloro-4-[p-(carbomethoxy)thiophenoxy]-2-butanone (10) with hydroxylamine under carefully controlled conditions gave the corresponding oxime 33. Conversion of this oxime to 1-phthalimido-4-[p-(carbomethoxy)thiophenoxy]-2-butanone oxime (4) was carried out by its reaction with potassium phthalimide using crown 18 ether as a catalyst. Hydrazinolysis of compound 4 gave 1-amino-4-[p-(carbomethoxy)thiophenoxy]-2-butanone oxime (5), which was used for the construction of the title compound 2 by modification of the Boon and Leigh procedure. An alternate synthesis utilizing 1-hydroxy-4-[p-(carbomethoxy)thiophenoxy]-2-butanone (11) and 4-hydroxy-2,5,6-triaminopyrimidine has also been carried out. Compound 2 did not exhibit any antifolate activity against Lactobacillus casei or Streptococcus faecium. The dithionite reduction product, 7,8-dihydro-11-thiohomofolic acid, was able to function as a substrate of L. casei dihydrofolate reductase. The catalytic reduction product of 2, consisting of a mixture of diastereomers, exhibited powerful antifolate activity against both these organisms.

Ultrastructure of a plasma-cell myeloma in the mandible

Tumor cells exhibited large amounts of rough endoplasmic reticulum arranged in a lamellar pattern, large numbers of mitochondria with a perinuclear distribution, and a prominent Golgi complex, but only a small number of immunoglobulin granules. No crystalline structures of immunoglobulins were observed. Nuclei exhibited patchy condensation of chromatin and large nucleoli. The ultrastructural features suggest that this case could be a "resecretory" myeloma.

Neurofibroma and schwannoma of the oral cavity. A clinical and ultrastructural study

The clinical parameters of fifty-five cases accessioned as neurofibroma and schwannoma of the oral cavity were reviewed. An electron microscope study was performed on several cases. The component cells of neurofibroma were spindle shaped, with bundles of collagen fibrils between cells. Junctional complexes were observed between adjacent cells. Component cells of the schwannoma showed numerous convoluted cytoplasmic processes. Reduplication of basal lamina was frequently observed and formed the material in the hyalinized area of Verocay bodies.