Remineralization by a monofluorophosphate dentifrice in vitro of root dentin softened by artificial caries

Artificial caries-softened dentin lesions in root surfaces were treated with 50% slurries of a monofluorophosphate (MFP) dentifrice or a placebo dentifrice twice daily for ten days. Between dentifrice treatments, the lesions were kept in a remineralizing solution. Both treatments resulted in statistically significant remineralization, with the MFP dentifrice being significantly better than the placebo. Deposition of new mineral from the MFP dentifrice occurred about equally at or within the surface zone and at the deepest part of the lesion. Mineral deposition from the placebo appeared to be more uniformly distributed within the lesion.

Characterization of monoclonal antibodies directed against HLA class II molecules

Four MAbs recognizing HLA class II antigens were produced by immunization with human leukemic cells, and were characterized through immunoprecipitation and cell distribution studies. They were tested against a panel of normal and leukemic cells, Epstein-Barr virus (EBV)-transformed homozygous typing cells (HTC)s, deletion mutant cell lines, and 11 other cell lines. The immunochemical studies revealed the presence of two bands of 34 and 28 kD, corresponding to the alpha- and beta-subunits of HLA class II antigens, respectively. The cell distribution studies led to the conclusion that GRB1, GRB2, and GRB3 MAbs recognize the HLA-DR monomorphic antigens, and that the GRB4 MAb seems to recognize basically the DR molecules but shows also a cross-reaction to DP molecules.

Cost containment in surgical pathology

We have discussed some of the methods that might be used in approaching fiscal control of the anatomic pathology laboratory. The pathologist, in a unique position as manager and physician, must assume a leadership role in this area. Now more than ever, these qualities must be used to direct the laboratory to a more productive and cost efficient plane.

Dermatology manpower projections

Since an oversupply of physician specialists leads to a waste of professional resources, planning of the number of physicians may be desirable. A model projecting the future supply of dermatologists was formulated on the basis of current residency capacity, which produces about 270 dermatologists per year, and on experience regarding the average length of active clinical practice. How changes in the training capacity affect the future supply of dermatologists was also examined. The model projects an equilibrium supply of about 9,500 dermatologists, or 3.2 per 100,000 population early in the 21st century, provided the number of new graduates remains at its present level. Assuming no economic barriers to access, 2.8 to three dermatologists per 100,000 population should be adequate to meet demand. Because of many unpredictable factors, periodic reassessment of dermatology training capacity is necessary.

Biodegradation and aneurysm formation in umbilical vein grafts. Observations and a realistic strategy

In a series of 756 glutaraldehyde-stabilized umbilical vein grafts implanted over a 7 1/2-year period, aneurysms were identified in seven cases. The earliest aneurysm was seen at 31 months after implantation and the remainder between 43 and 79 months after surgery. Corrective surgery was performed in five cases and succeeded in four. Although definite mechanisms have not been identified, mechanical fatigue, reversal of aldehyde crosslinks, and immunologic factors may be operative. The pathologic changes include: (1) actual dilation of both graft and mesh with or without intraluminal thrombus and, (2) maintenance of graft diameter with erosion of the umbilical vein and polyester mesh rupture leading to perigraft hematoma and false aneurysm formation. Microscopic examination and infrared spectral analysis confirmed the presence of host-contributed lipid in some specimens. Although this is a low incidence of aneurysm formation, umbilical vein grafts should be selected primarily for patients with limited life expectancy or for whom alternative materials with comparable or superior patency rates are not available or acceptable. Periodic angiography, particularly after 3 or 4 years, is recommended as a routine part of follow-up examinations. Improved graft materials and control of host environmental factors are potential means to reduce the noted degradation.

Survey of diplomates of the American Board of Dental Public Health, 1980

A survey was mailed to all active diplomates of the American Board of Dental Public Health in January of 1980 requesting information regarding activities for the period including January 1978 to December 1979. Eighty-two of the then 86 full-time active diplomates responded to the survey. Comparisons with the results of a survey conducted 11 years earlier by Johnson and Bernstein were made with respect to employment, primary activity within employment, and degree of participation in workshops, conferences and seminars. An analysis of results from the two surveys indicates few significant changes in many areas.

The effects of oral iodized oil on intelligence, thyroid status, and somatic growth in school-age children from an area of endemic goiter

One hundred goitrous school children received 475 mg iodized oil by mouth, while 100 controls received mineral oil, on a double-blind basis. On follow-up 22 months later the urinary iodine had increased and goiter size had decreased in both groups, more strikingly in the iodine-treated children. There were no consistent differences between the two treatment groups in rate of somatic growth or performance on the Stanford-Binet and Bender tests. Because of the complexities introduced by increases in urinary iodine in the controls, we compared goiter reduction with improvement in IQ score in all children, regardless of group, and found a significant relationship (p = 0.014), particularly in girls (p = 0.029). We conclude that oral iodized oil is an attractive alternative to its injection but we recommend an approximate doubling of the dose used here for more effective control. Also, while our data are not conclusive, they support the possibility that correction of iodine deficiency may improve mental performance in school age children, particularly girls.

Adherence of human peripheral blood lymphocytes to measles-virus infected cells: modulation by solubilized rhesus erythrocyte membranes and carbohydrates

The adherence of human peripheral blood lymphocytes to HeLa cells persistently infected with measles virus (HeLa-K11) was studied. The following data were observed. (i) The proportion of HeLa-K11 cells with adherent human peripheral blood lymphocytes of rhesus monkey erythrocytes was similar over a wide range of ratios of HeLa-K11 cells to lymphocytes or erythrocytes. (ii) The great majority of human peripheral blood lymphocytes and erythrocytes reacted with the same HeLa-K11 cell (iii). The adherence of lymphocytes or erythrocytes to HeLa-K11 cells was blocked by rabbit anti-measles virus antibody or solubilized monkey erythrocyte membranes. The pretreatment of erythrocytes or lymphocytes with receptor-destroying enzyme did not alter their adherence properties. (iv) The pattern of inhibition observed with several carbohydrates was similar in both the erythrocyte and the lymphocyte adherence assays. These data are consistent with the possibility that the receptor present on both rhesus monkey erythrocytes and human lymphocytes has similar specificities and biochemical composition.

Drought resistance in spring wheat cultivars. II.* Effects on plant water relations

We studied cultivar and drought effects on the water relations of a large set of cultivars of bread wheat (Triticum aestivum L.), durum wheat (T. turgidum), triticale (X Tritosecale Wittmack) and barley (Hordeum vulgare L.), grown in field plots in north-western Mexico in the presence and absence of simulated late drought. Leaf water potential (Ψ) and osmotic potential (π), and leaf permeability (LP) to viscous air flow were measured between 1000 and 1600 hours on many dates; leaf turgor potential (p) was calculated. Drought caused associated reductions in Ψ, π and LP. Cultivar effects on these variables were usually significant on given dates, and reasonably consistent between dates and drought intensities in the case of Ψ, but less so for π and LP. There were consistent positive phenotypic correlations between Ψ and LP, and Ψ and anthesis date, and a negative correlation between Ψ and stature in the absence of drought. The relationship of LP to Ψ for different cultivars differed significantly: in particular, tall bread wheats had lower LP than dwarf cultivars at high values of Ψ, whereas at low Ψ they had higher LP than the dwarf cultivars. There was general osmotic adjustment, and a tendency for the relationship of p to Ψ to vary between cultivars. Irrespective of statistical significance, the effects of cultivar were generally small relative to those of drought intensity.