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L Laster

Publications and source records attributed to L Laster.

16 recordsLinked to original sources

Dining out.

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Adult

A comparative study of herpes simplex infections in renal transplant and leukemic patients.

Herpes simplex virus (HSV) reactivation and lesion formation were studied in 68 renal transplant recipients and 30 leukemic patients. Antibody titers to HSV were determined, and seropositive patients were examined three times weekly for up to one month. Surveillance cultures were taken for oral HSV, and HSV culture and cytology were done for all oral lesions found. In a smaller number of patients, immune responses were determined. HSV reactivation was similar in the transplant and leukemic groups (46.8% vs. 50%), but a significant difference in the incidence of HSV lesion formation was noted between the two groups. Of the transplant patients in whom HSV reactivated, 31.8% developed HSV lesions; of leukemic patients in whom HSV reactivated, 100% developed HSV lesions. Differences in the incidence of formation of HSV lesions in these groups of immunosuppressed patients suggest that reactivation of HSV and formation of HSV lesions may involve different mechanisms. Low levels of antibody-dependent cellular cytotoxicity were noted in leukemic patients and may contribute to increased formation of HSV lesions in this group.

Adolescent

Biochemical aspects of orthodontic tooth movement. I. Cyclic nucleotide and prostaglandin concentrations in tissues surrounding orthodontically treated teeth in vivo.

The objective of this study was to extract and assay cyclic nucleotides and prostaglandins from tissues surrounding orthodontically treated canines in cats. Seven groups of three to five female cats were treated by 80 g tipping force to one maxillary canine for 0 to 28 days. Tissue samples were removed from sites of compression and tension around treated teeth, and from the corresponding control sites. Cyclic nucleotides and prostaglandins were simultaneously extracted by a solvent system at 0 to -5 degrees C. A portion of the aqueous fraction was used for cAMP assay by a binding protein method; cGMP was purified by column chromatography and measured by radioimmunoassay. The solvent fraction was dried, reconstituted with assay buffer, and each of the prostaglandins measured by radioimmunoassay. Analysis of variance showed no significant differences between summary control and treated sites at each of the time periods studied. However, when interactions at secondary and tertiary levels were considered (such as tension and compression, position [apical-gingival sites] of tissue sample, and jaws), significant differences were found in PGE, cAMP, and PGF2 alpha values. These results demonstrate that alterations in the levels of each of these substances in tissues surrounding teeth may be brought about by long-term applications of orthodontic force in vivo. The method of tissue sampling, however, does not permit measurement of the levels of these substances in target cells alone, thus diluting the acute response that may have occurred in these cells.

Alveolar Process

Comparative longitudinal study of 2 methods of scheduling maintenance visits; 2-year data.

This report compares the clinical and microbiological status of 2 groups of subjects with treated periodontis on different maintenance schedules. 43 control (C) subjects were given prophylaxes every 3 months. 40 test (T) subjects were given this service on a flexible schedule according to the proportions of spirochetes and/or motile rods in fresh smears of subgingival scrapings. Both groups were examined every 6 months clinically and microbiologically. This report presents base line, 1- and 2-year data. Generally, mean values for both groups did not differ significantly from one another. Both groups exhibited comparable increases in GI and PLI scores during the first 2 years of this study. No change in probing depth was noted between base line and the 2-year examination. However, a slight increase in attachment level, as determined by probing, was noted in both groups. Both groups also exhibited similar proportions of bacterial morphotypes at base line and subsequent examinations. Disease recurrence, defined as an increase in probing depth of 3 mm or more from base line on any tooth surface during the 2-year period, tended to be more prevalent in the C than in the T group (15/43 C and 9/40 T subjects). However, the proportional difference between the groups was not statistically significant. Subjects with disease recurrence in the T group had greater proportions of spirochetes at base line than subjects in the same group without disease recurrence (20.2% versus 9.8%, p less than 0.01). This difference in proportions persisted if both groups were examined jointly, but was only of borderline significance (16.0% versus 10.5%, p = 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult

Transgingival probing as a potential estimator of alveolar bone level.

The validity of using a periodontal probe for the transgingival sounding of the alveolar crest level has been demonstrated for buccal surfaces of the jaw. The measurements from the occlusal surfaces of the teeth to the estimated level of the alveolar crest using this technique accurately reflected the actual distances measured after surgical exposure of the alveolar crest at these sites.

Alveolar Process

Serum complement profiles in infants and children.

The purpose of this study was to examine normal serum values for the complement components, C3, C4, and C5, and total hemolytic complement (CH50) activity in 163 healthy infants and children, in the age range from birth through 14 years. There were statistically significant relationships of C3, C4, and C5, but not CH50 with age. None of the complement components or CH50 could be differentiated by sex or race. Tolerance limits for high and low values were projected for each complement measurement for 75%, 90%, and 95% of the general population. Our data confirm the differences in complement levels between children and adults and demonstrate a wide range of values within each group, reflecting the biologic variability of complement measurements. These results emphasize the importance of establishing normal pediatric values in any laboratory that measures complement profiles in various diseases of childhood.

Adolescent

An evaluation of clinical tooth mobility measurements.

This study evaluated the reliability and reproducibility of the modified Miller Index of horizontal tooth mobility. Each of three periodontists utilizing the modified Miller Index assessed the horizontal tooth mobility of 50 teeth in five subjects. The same teeth were also evaluated by the periodontometer. The results of these two methods were then compared. It was found that: (1) there were a high positive correlation between the periodontists' (pooled) assessment of clinical tooth mobility and the measurements of the periodontometer, (2) in any given patient the three periodontists (pooled) were highly accurate in their ability to rank teeth in order of their mobility as determined by the periodontometer, and (3) the periodontists (individually) were not as consistent when comparing teeth with the Miller Index across different subjects. The periodontists did not accurately utilize the Miller Index as it was originally described. It appears that the periodontists either ignored the reference to 1 mm in the description of the Miller Index, or they were unable to estimate what constitutes 1 mm of movemnet in the mouth. The periodontists all consistently scored as a 2 degrees mobility a tooth that moved approximately 0.5 mm not 1.0 mm as described by Miller. It is suggested that the modified Miller Index as described here provides an efficacious system for evaluating horizontal tooth mobility. It provides accurate, reproducible mobility scores in clinical studies requiring an estimation of this parameter. However, for individual teeth, when the clinician or researcher is trying to evaluate the effects of therapy on the periodontium and relatively few evaluation are made, the modified Miller Index may not provide the required degree of sensitively.

Adult