Effect of locally delivered minocycline microspheres on markers of bone resorption.

BACKGROUND: Gingival crevicular fluid (GCF) biomarkers associated with bone resorption may be useful to determine periodontal disease status and response to therapy. The pyridinoline cross-linked carboxy-terminal telopeptide of type I collagen (ICTP), a bone-specific degradation product, and interleukin 1-beta (IL-1), a potent bone-resorptive cytokine, have both been associated with periodontal disease activity. Minocycline is a tetracycline derivative possessing antimicrobial effects on periodontal pathogens and inhibitory properties on matrix metalloproteinases (MMPs) associated with tissue destruction. The aim of this study was to evaluate the effect of periodontal treatment in the form of scaling and root planing (SRP) and locally administered minocycline microspheres on the GCF levels of ICTP and IL-1. METHODS: Forty-eight chronic periodontitis patients were randomly assigned to 2 groups (SRP plus subgingival application of vehicle control [SRP + V], or SRP plus subgingival application of minocycline microspheres [SRP + M]) and monitored at 8 sites per subject at baseline and 1, 3, and 6 months. Four shallow (PD < or = 3 mm) and 4 deep (PD > or = 5 mm) sites were evaluated for both marker levels and for probing depth (PD), clinical attachment level (CAL), and bleeding on probing (BOP). Eight periodontally healthy control subjects with no probing depths >3 mm and no loss of attachment were also monitored at the same time intervals. GCF levels of ICTP and IL-1 were determined using radioimmunoassay and enzyme-linked immunosorbent assay techniques, respectively. RESULTS: Significant differences (P<0.001) in GCF levels of ICTP and IL-1 were found between deep and shallow sites at all time points in both treatment groups. In addition, healthy subjects demonstrated significantly reduced levels of both markers compared to both shallow and deep sites in periodontitis patients (P <0.001). Only the SRP + M treated patients exhibited significant reductions (P <0.05) in both ICTP and IL-1 levels 1 month after treatment. Furthermore, the SRP + M group demonstrated significantly lower IL-1 levels (P <0.02) at 1 month compared to the SRP + V group. CONCLUSIONS: Results of this study indicate that GCF levels of ICTP and IL-1 correlate with clinical measures of periodontal disease and may aid in assessing disease status and response to periodontal therapy. Furthermore, local administration of minocycline microspheres led to a potent short-term reduction in GCF IL-1 levels. Additional studies are needed to address whether repeated administration of scaling and root planing along with minocycline microspheres will achieve long-term reductions in GCF ICTP and IL-1 levels.

Extended reproductive roles of the fruitless gene in Drosophila melanogaster revealed by behavioral analysis of new fru mutants.

The fruitless mutants fru3 and fru4 were assessed for sex-specific reproductive-behavioral phenotypes and compared to the previously reported fru mutants. Among the several behavioral anomalies exhibited by males expressing these relatively new mutations, some are unique. fru3 and fru4 males are less stimulated to court females than fru1 and fru2. No courtship pulse song is generated by either fru3 or fru4 males, even though they perform brief wing extensions. fru3 and fru4 males display significantly less chaining behavior than do fru1 males. The hierarchy of courtship responses by fru males directed toward females vs. males, when presented with both sexes simultaneously, is that fru1 males perform vigorous and indiscriminant courtship directed at either sex; fru4 males are similarly indiscriminant, but courtship levels were lower than fru1; fru2 males prefer females; fru3 males show a courtship bias toward males. fru3 and fru4 males essentially lack the Muscle of Lawrence (MOL). On several reproductive criteria, there was no difference between fru-variant females and fru+. The increases in phenotypic severity measured for the new mutants are discussed in the context of the emerging molecular genetics of fru and with regard to the gene's position within the sex-determination pathway.