Immunohistochemical localization of basement membrane components during hair follicle morphogenesis.

Specific antisera were used to investigate the distributions of several basement membrane zone (BMZ) components, namely, bullous pemphigoid antigen (BPA), heparan sulfate proteoglycan (HSPG), laminin, and type IV collagen, during the development of hair follicles in late embryo rats. BPA was not visible by indirect immunofluorescence in the BMZ before epidermal involution but appeared in all regions of BMZ after this had occurred. As follicular length increased during maturation, the distribution of BPA was no longer uniform, being reduced or absent from the BMZ around the lower part of the elongating follicle. HSPG was associated with the basal cell layer prior to the appearance of hair follicle primordia and became BMZ-associated before birth but after follicle buds were first observed. HSPG was also found to be associated with the basal cell surfaces in the epidermis, but not in the hair follicle. Laminin and type IV collagen were continually present in epidermal and follicular BMZ both before and during development of hair follicles and were later present in the dermal papilla matrix. From these observations we conclude that (1) laminin and type IV collagen are functionally important for BMZ integrity before and during epidermal and follicular maturation, (2) HSPG may have a cell surface function in epidermis as well as roles in BMZ organization and properties, and (3) the distribution of BPA is indicative of its association only with regions of tissue not involved in morphogenetic change. We also suggest that the cell-matrix interactions documented for BPA, HSPG, laminin, and fibronectin may depend on the type of tissue involved and its state of development, differentiation, or repair.

Human oral retention of zinc from mouthwashes containing zinc salts and its relevance to dental plaque control.

Subjects using 30 mM zinc phenolsulphonate as a mouthwash retained 12 per cent of the zinc. Salivary zinc concentration was increased by using mouthwashes containing 17-35 mM zinc as the sulphate, phenolsulphonate or citrate. For 17 mM zinc sulphate or phenolsulphonate, the effect lasted 3-4 h. Zinc retained in the mouth gave visible fluorescence after rinsing with 8-hydroxyquinoline and was particularly evident on the tongue, cheek mucosa and dental plaque. The concentration of zinc in plaque was increased 13-19-fold 1 h after using 31 or 18 mM zinc phenolsulphonate. A 3-fold increase was still present 6 h later for the 31 mM mouthwash. Zinc salts inhibited acid production from [14C]-glucose in vitro by plaque at concentrations which were found in plaque in vivo after using the mouthwashes. The effect of zinc on the metabolic activity of plaque may reduce the growth rate of plaque-bacteria and so decrease plaque growth.

Enzymes of Trichomonas foetus. Separation and properties of two beta-galactosidases.

The beta-galactosidase activity in extracts of Trichomonas foetus is separable into two fractions by gel filtration on Sephadex G-200. When o-nitrophenyl beta-d-galactoside is used as substrate the first fraction to be eluted, beta-galactosidase 1, has 50 times the activity (units per mg of protein) of the crude preparation. This fraction is activated by Mn(2+) and Co(2+) and inhibited by Hg(2+) and EDTA. In the presence of Mn(2+) the pH optimum for the hydrolysis of o-nitrophenyl beta-d-galactoside or lactose is 5.8-6.0. beta-Galactosidase 1 is an exoglycosidase that releases beta-linked galactose joined to aliphatic and various carbohydrate aglycones. Hydrolysis is prevented, however, by a substituent on either the subterminal sugar or the terminal non-reducing beta-galactosyl residue in an oligosaccharide. The second fraction, beta-galactosidase 2, is not activated by metal ions or inhibited by EDTA and has a broad pH optimum from 4.5 to 6.0.

The effect of dentifrices containing zinc citrate on plaque growth and oral zinc levels.

Zinc salts have previously been shown to possess antiplaque activity in solution but this activity has as yet not been reported for dentifrices. The purpose of the present investigation was to establish the effect of dentifrices containing zinc citrate (ZCT) on plaque growth and on the concentration of zinc in saliva and plaque. Plaque growth inhibition was studied over periods of time approximating to intervals for normal oral hygiene procedures. Zinc in saliva and plaque was measured by atomic absorption spectroscopy. Elevated zinc levels in saliva were observed for 3-4 h after brushing with the zinc citrate dentifrice. Similarly, raised levels of zinc were encountered in plaque 1 h following contact with a slurry of a dentifrice containing ZCT. Increased concentrations of zinc were observed in plaque fluid and plaque residue. The plaque growth data from 88 participants in 5 studies revealed that plaque regrowth over 16 h or 22 h was reduced by dentifrices containing 0.5% ZCT, compared to placebo dentifrices. Dentifrices which contained 0.5% ZCT or 0.4% stannous fluoride, had similar inhibitory effects on plaque. Further analysis of the data showed that subjects with high rates of plaque growth benefited more from the zinc dentifrices than those with low rates of plaque growth. It is suggested that the effect on plaque was related to zinc concentration in the dentifrice rather than total dose applied, and that the main effect of zinc was to inhibit the extension of existing plaque.

Interleukin-1 beta (IL-1 beta) levels in gingival crevicular fluid from adults with previous evidence of destructive periodontitis. A cross sectional study.

We have estimated the levels of Interleukin-1 beta (IL-1 beta) by ELISA in gingival crevicular fluid (GCF) at 58 sites from 37 patients with adult periodontitis. GCF was collected for 5 s on filter papers and a 2nd sample was collected for 30 s 1 min later. 68/116 strips yielded detectable levels of IL-1 beta. IL-1 beta was present in both the 1st and 2nd samples at 28 sites, in the 1st only at 4 sites and in the 2nd only at 8 sites; 18 sites were below the level of detection for the assay. When the concentrations of IL-1 beta were calculated in the original volume of GCF on each strip, the mean value for positive strips was 34.16 +/- 29.45 (SD) pg/microliters with a range from 1.75 to 97.13 pg/microliters. There were no statistically significant correlations with the plaque index, bleeding index or probable crevice depth (pocket depth). The results indicate that IL-1 is present in the GCF from a proportion of sites with evidence of previous periodontal destruction.