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The purpose of this 6‐week, single‐blinded, randomized clinical trial was to determine if the use of an interproximal brush, with or without a tracking device, is more effective than an oral irrigator in improving interproximal probing depth (PD), clinical attachment level (CAL), plaque index (PI), gingival index (GI), bleeding on probing (BOP), and inflammatory markers. Seventy‐six patients with Stages III–IV, Grade B periodontitis and a 5–7 mm posterior interproximal PD with BOP were randomized: (1) interproximal brush alone (IB; n= 26), (2) interproximal brush with tracking device (TD; n= 23), (3) oral irrigator (OI; n= 27). Participants used devices once daily for 6 weeks. Clinical measurements (PD, CAL, PI, BOP, GI) and gingival crevicular fluid (GCF) samples were collected at baseline and 6 weeks. All groups showed a significant reduction in PD and CAL (≥1.1 mm, p< 0.0001) and improvement in BOP (≥56%, p< 0.0001) and GI (≥82%, p< 0.001) at the experimental site with no differences among groups. The IB and IB+TD groups showed a significant reduction in PI (≥0.9, p≤ 0.01). Interleukin (IL)‐1β was reduced in all groups (p= 0.006), but IB+TB more than OI (p≤ 0.05). IL‐10 was reduced among all groups (p= 0.01), while interferon‐gamma significantly increased (p= 0.01) in all groups. IB and OI improved clinical parameters of PD and CAL and reduced inflammatory markers (BOP, GI, GCF IL‐1β). IB had better interproximal plaque reduction. Tracking did not significantly improve clinical parameters compared with the IB and OI groups, suggesting future modifications are needed.

The objective of this exploratory study was to evaluate inflammatory markers in periodontal maintenance patients from a randomized, double‐masked, parallel intervention clinical trial comparing local simvastatin (SIM) to carrier alone following mini‐flap access. Fifty patients with a 6–9‐mm inflamed pocket during periodontal maintenance therapy (PMT) were treated with papilla reflection (PR)/root planing and placement of 2.2‐mg simvastatin in methylcellulose (SIM/MCL) or methylcellulose alone (MCL). A small piece of interproximal soft tissue was harvested at baseline and 2 weeks postoperatively, gingival crevicular fluid (GCF) obtained at baseline, 2 weeks and 12 months, and bleeding on probing (BOP) and clinical attachment level (CAL) were measured at baseline and 12 months. Pro‐inflammatory interleukin (IL)‐6 and anti‐inflammatory IL‐10 gene activation were determined by reverse transcriptase polymerase chain reaction (rt‐PCR). GCF IL‐1β, IL‐6, IL‐10, and vascular endothelial growth factor (VEGF‐A) were measured with multiplex technology. Comparisons between groups and over time used logistic regression and general estimating equations. Associations between inflammatory markers and 12‐month outcomes used Wilcoxon rank sum tests or Pearson correlations. Patients in the SIM group had 4.17 greater odds (p= 0.047) of improved BOP at 12 months. Median IL‐6 and VEGF were significantly increased for all patients after 2 weeks of healing (p< 0.0001 and p= 0.03, respectively), while median IL‐10 gene activation was increased after 2 weeks in SIM/MCL (NS). Overall, elevated GCF IL‐10 at 2 weeks was significantly correlated with improved CAL at 12 months (r= −0.32, p= 0.03). Local SIM/MCL may have anti‐inflammatory effects that potentially are associated with improved long‐term CAL outcomes.

The purpose of this double‐masked, randomized, controlled trial was to determine if the local application of simvastatin (SIM), combined with minimally invasive papilla reflection and root planing (PR/RP), is effective in improving clinical attachment level (CAL), probing depth (PD) reduction, and increasing interproximal bone height (IBH) in persistent 6–9 mm periodontal pockets in patients receiving periodontal maintenance therapy (PMT). Fifty patients with Stage III, Grade B periodontitis presenting with a 6–9 mm interproximal PD with a history of bleeding on probing (BOP) were included in the study. Experimental [PR/RP+SIM/methylcellulose (MCL); n= 27] and control (PR/RP+MCL; n= 23) therapies were randomly assigned. Root surfaces were accessed via reflection of interproximal papillae, followed by RP assisted with endoscope evaluation, acid etching, and SIM/MCL or MCL application. CAL, PD, BOP, plaque presence, and IBH (using standardized vertical bitewing radiographs) were evaluated at baseline and 12 months. Measurements were compared by group and time using Chi‐square, Wilcoxon rank‐sum, and t‐tests. Both PR/RP+SIM/MCL and PR/RP+MCL, respectively, resulted in improvements in clinical outcomes (CAL: ‐1.9 ± 0.3 mm, p< 0.0001; ‐1.0 ± 0.3 mm, p< 0.003; PD: ‐2.3 mm ± 0.3, p< 0.0001; ‐1.3 mm ± 0.3, p< 0.0001; BOP: ‐58.7%; ‐41.7%, p< 0.05) and stable IBH (‐0.2 ± 0.12, ‐0.4 ± 0.2, p= 0.22) from baseline to 12 months post‐therapy. PR/RP+SIM/MCL had more improvement in CAL (p= 0.03), PD (p= 0.007), and BOP (p= 0.047). The addition of SIM/MCL to PR/RP improved CAL, PD, and BOP compared with PR/RP alone in periodontal maintenance patients.

Save for the Civil War, what occurred after a carpenter glimpsed a flash of yellow 150 years ago was the biggest story of the nineteenth century. It was 150 years [...]

Sexy and melancholy, festive and forlorn, the island has always heated the Yankee imagination. The author visits there in the late afternoon of a straitened era and looks back on [...]

The genus Desulfonemabelongs to the deltaproteobacterial family Desulfobacteraceaeand comprises marine, sulfate-reducing bacteria that form filaments and move by gliding. This study reports on the complete, manually annotated genomes of Dn. limicola5ac10T (6.91 Mbp; 6,207 CDS) and Dn. magnum4be13T (8.03 Mbp; 9,970 CDS), integrated with substrate-specific proteome profiles (8 vs. 11). The richness in mobile genetic elements is shared with other Desulfobacteraceaemembers, corroborating horizontal gene transfer as major driver in shaping the genomes of this family. The catabolic networks of Dn. limicolaand Dn. magnumhave the following general characteristics: 98 versus145 genes assigned (having genomic shares of 1.7 vs. 2.2%), 92.5 versus89.7% proteomic coverage, and scattered gene clusters for substrate degradation and energy metabolism. The Dn. magnumtypifying capacity for aromatic compound degradation (e.g., p-cresol, 3-phenylpropionate) requires 48 genes organized in operon-like structures (87.7% proteomic coverage; no homologs in Dn. limicola). The protein complements for aliphatic compound degradation, central pathways, and energy metabolism are highly similar between both genomes and were identified to a large extent (69–96%). The differential protein profiles revealed a high degree of substrate-specificity for peripheral reaction sequences (forming central intermediates), agreeing with the high number of sensory/regulatory proteins predicted for both strains. By contrast, central pathways and modules of the energy metabolism were constitutively formed under the tested substrate conditions. In accord with their natural habitats that are subject to fluctuating changes of physicochemical parameters, both Desulfonemastrains are well equipped to cope with various stress conditions. Next to superoxide dismutase and catalase also desulfoferredoxin and rubredoxin oxidoreductase are formed to counter exposure to molecular oxygen. A variety of proteases and chaperones were detected that function in maintaining cellular homeostasis upon heat or cold shock. Furthermore, glycine betaine/proline betaine transport systems can respond to hyperosmotic stress. Gliding movement probably relies on twitching motility via type-IV pili or adventurous motility. Taken together, this proteogenomic study demonstrates the adaptability of Dn. limicolaand Dn. magnumto its dynamic habitats by means of flexible catabolism and extensive stress response capacities.

The betaproteobacterial genus Aromatoleumcomprises facultative denitrifiers specialized in the anaerobic degradation of recalcitrant organic compounds (aromatic and terpenoid). This study reports on the complete and manually annotated genomes of Ar. petroleiToN1T (5.41 Mbp) and Ar. bremensePbN1T (4.38 Mbp), which cover the phylogenetic breadth of the genus Aromatoleumtogether with previously genome sequenced Ar. aromaticumEbN1T [Rabus et al., Arch Microbiol. 2005 Jan;183(1):27–36]. The gene clusters for the anaerobic degradation of aromatic and terpenoid (strain ToN1T only) compounds are scattered across the genomes of strains ToN1T and PbN1T. The richness in mobile genetic elements is shared with other Aromatoleumspp., substantiating that horizontal gene transfer should have been a major driver in shaping the genomes of this genus. The composite catabolic network of strains ToN1T and PbN1T comprises 88 proteins, the coding genes of which occupy 86.1 and 76.4 kbp (1.59 and 1.75%) of the respective genome. The strain-specific gene clusters for anaerobic degradation of ethyl-/propylbenzene (strain PbN1T) and toluene/monoterpenes (strain ToN1T) share high similarity with their counterparts in Ar. aromaticumstrains EbN1T and pCyN1, respectively. Glucose is degraded via the ED-pathway in strain ToN1T, while gluconeogenesis proceeds via the reverse EMP-pathway in strains ToN1T, PbN1T, and EbN1T. The diazotrophic, endophytic lifestyle of closest related genus Azoarcusis known to be associated with nitrogenase and type-6 secretion system (T6SS). By contrast, strains ToN1T, PbN1T, and EbN1T lack nifgenes for nitrogenase (including cofactor synthesis and enzyme maturation). Moreover, strains PbN1T and EbN1T do not possess tssgenes for T6SS, while strain ToN1T does and facultative endophytic “Aromatoleum” sp. CIB is known to even have both. These findings underpin the functional heterogeneity among Aromatoleummembers, correlating with the high plasticity of their genomes.

Efficient methods to treat persistent pockets during periodontal maintenance therapy (PMT) require further investigation. The hypothesis of this randomized controlled clinical trial was that local application of enamel matrix derivative (EMD) added to papilla reflection/root preparation (PR/RP) could enhance clinical and inflammatory outcomes, primarily clinical attachment level (CAL). Fifty PMT patients with generalized stage III‐IV, grade B periodontitis presenting with a 6‐ to 9‐mm interproximal PD were randomly allocated to (PR/RP+EMD; n = 24) and control (PR/RP+saline; n = 26) therapies by sex and smoking status. Roots were treated with reflection of interproximal papillae, root planing assisted with endoscope evaluation, and acid etching, followed by EMD or saline application. Probing depth (PD), CAL, plaque index (PI), and interproximal bone height were evaluated at baseline and 12‐months post‐therapy. Gingival crevicular fluid, bleeding on probing (BOP), and interleukin‐1β were tested (ELISA) at baseline, 2 weeks, and 6 and 12 months. Groups were compared over time and between groups with Wilcoxon Rank Sum and t‐tests. Both PR/RP+ EMD and PR/RP+S resulted in significant improvements in clinical outcomes (PD and CAL, BOP) from baseline to 12 months. No significant differences were found in clinical or inflammatory outcomes between the experimental and control groups. The addition of EMD to PR/RP does not significantly improve clinical or inflammatory outcomes compared with PR/RP alone during periodontal maintenance therapy.

The fixation and stability of dental implants is governed by the quality of the underlying alveolar bone. The current study investigates if the dual delivery of calcium chelating bone therapeutics from mineralized nanofiber fragments can help regenerate alveolar bone in vivo. Alendronate (ALN) or/and bone morphogenetic protein-2-mimicking peptide conjugated to a heptaglutamate moiety (E7-BMP-2) were incorporated onto mineralized nanofiber fragments of polylactide-co-glycolide–collagen–gelatin (PCG in 2:1:1 weight ratios) via calcium coupling/chelation. Two mg of the single-loaded (ALN) and coloaded (ALN + E7-BMP-2) mineralized nanofiber PCG grafts was filled into critical-sized (2 mm diameter × 2 mm depth) alveolar bone defects in rat maxillae and let heal for 4 weeks. X-ray microcomputed tomography analysis of the retrieved maxillae revealed significantly elevated new bone formation parameters for the ALN and ALN + E7-BMP-2 groups compared with the unfilled defect controls. However, no significant differences between the single and coloaded nanofiber grafts were noted. Furthermore, the histopathological analysis of the tissue sections divulged islands of new bone tissue in the ALN and ALN + E7-BMP-2 groups, whereas the control defect was covered with gingival tissue. Together, the presented strategy using mineralized nanofiber fragments in the sustained delivery of dual calcium chelating therapeutics could have potential applications in enhancing bone regeneration.

A study demonstrating that the platypus genome comprises of more than 200 small nuclear (sno) RNAs among hundreds of other different non-protein-coding (npc) RNAs and their comparison with significant mammalian species and other vertebrate is discussed. It is suggested that high-copy retroposition via many host gene-promoted transcription units is a novel method for integrating housekeeping function and SINE-like dispersal and presents a new perspective in the evolution of unique snoRNA function.

Analysis of genomic sequence of rat major histocompatibility complex is given. The analysis has resulted in the identification of 220 genes located within the sequenced interval.

Research has been conducted on molecular haplotyping. The authors describe the method developed for fast and efficient molecular haplotyping which consists of clone pool screening by PCR coupled with a mass spectrometric procedure.

Purpose. This study evaluated the effects of smoking status on retrospective clinical and radiographic measures of periodontal disease and compared these to prospective changes in digital radiographic bone height. Methods. Clinical data on moderate (4 to 6 mm) and severe ([is greater than] 6 mm) periodontal pocket depths, and bleeding on probing, were obtained from 95 subjects on suggested three-month supportive periodontal therapy (SPT) for AAP Class III/IV periodontitis. Standardized radiographic data were obtained concerning posterior interproximal alveolar bone height from 36 of the 95 subjects using computer-assisted digital technology at baseline and one year later. The subjects were divided into groups by smoking status: current, former, and never. Data were evaluated using a general linear statistical model. Results. Evaluation of clinical data showed that current smokers exhibited a significantly higher percentage of moderate (18%) and severe (1%) periodontal pockets than nonsmokers (10% and 0%, respectively; p [is less than] 0.002). Baseline radiographic interproximal bone height loss also was greater in current smokers (5.75 [+ or -] 1.07 v. 4.64 [+ or -] 1.16 mm). Bone loss over one year occurred in 5% of the sites, but was not significantly different among groups. Conclusion. Clinical periodontal pockets and bone loss accumulated more rapidly in smokers, even though they submitted to regular supportive periodontal therapy. Although this population was clinically compliant over a one year period, digital radiography showed a high incidence of detectable bone loss. The impact of smoking, however, may require longer than one year to show longitudinal changes. It is recommended that a periodic radiographic analysis on bone height be considered during SPT, and longer term studies be conducted in order to accurately identify the outcome of smoking status on this variable. Keywords, periodontal disease, smoking, tobacco, periodontal bone loss, supportive periodontal therapy., Introduction Little information is available on the prospective longitudinal effects of smoking on periodontal bone loss, particularly in subjects undergoing standardized supportive periodontal therapy. The purpose of this study was [...]

A true story of their final days on the Florida seashore ONE SUMMER AFTERNOON NOT SO VERY LONG AGO, the police department of Holmes Beach, Florida, a village on the [...]

Interactions between co-existing microorganisms deeply affect the physiology of the involved organisms and, ultimately, the function of the ecosystem as a whole. Copiotrophic Alteromonasare marine gammaproteobacteria that thrive during the late stages of phytoplankton blooms in the marine environment and in laboratory co-cultures with cyanobacteria such as Trichodesmium. The response of this heterotroph to the sometimes rapid and transient changes in nutrient supply when the phototroph crashes is not well understood. Here, we isolated and sequenced the strain Alteromonas macleodiistr. Te101 from a laboratory culture of Trichodesmium erythraeumIMS101, yielding a chromosome of 4.63 Mb and a single plasmid of 237 kb. Increasing salinities to ≥43 ppt inhibited the growth of Trichodesmiumbut stimulated growth of the associated Alteromonas. We characterized the transcriptomic responses of both microorganisms and identified the complement of active transcriptional start sites in Alteromonasat single-nucleotide resolution. In replicate cultures, a similar set of genes became activated in Alteromonaswhen growth rates of Trichodesmiumdeclined and mortality was high. The parallel activation of fliA, rpoSand of flagellar assembly and growth-related genes indicated that Alteromonasmight have increased cell motility, growth, and multiple biosynthetic activities. Genes with the highest expression in the data set were three small RNAs (Aln1a-c) that were identified as analogs of the small RNAs CsrB-C in E. colior RsmX-Z in pathogenic bacteria. Together with the carbon storage protein A (CsrA) homolog Te101_05290, these RNAs likely control the expression of numerous genes in responding to changes in the environment.

Background:Loss of alveolar ridge width and height after tooth extraction is well documented, but models to evaluate ridge preservation are neither standardized nor cost‐effective. This rat model characterizes the pattern of bone turnover and inflammation after extraction and bone grafting with or without local simvastatin (SIM). Methods:Fifty retired‐breeder rats underwent extraction of the maxillary right first molar and standard surgical defect creation under inhalation/local anesthesia. The left side of each animal served as unmanipulated control. Untreated groups (n = 8 to 9 per group) were compared (analysis of variance, ttest) at days 0, 7, 14, and 28 for alveolar ridge height and width and for markers of inflammation and bone turnover by microcomputed tomography, histology, and enzyme‐linked immunosorbent assay. Seventeen additional specimens had defects grafted with either bone mineralized matrix (BMM) or a BMM+SIM conjugate. Results:Extraction‐induced bone loss (BL) was noted on buccal, palatal, and interproximal height (P<0.05) and ridge width (P<0.01). Week 1 inflammation positively correlated with ridge height; thereafter, a more intense inflammatory reaction corresponded to reduction in alveolar bone height and density (r= 0.74; P<0.05; Spearman). BMM+SIM preserved the most interproximal bone height (P<0.01), increased ridge width and bone density (P<0.01), enhanced 7‐day prostaglandin E2 (P<0.01), and reduced 28‐day inflammation density (P<0.05). Conclusions:The standard defect used in the current study paralleled human postextraction alveolar BL. Defect grafting, especially BMM+SIM, reduced inflammation and preserved bone.

Differences in transcriptomes, transcription factor usage, and function have identified T follicular helper 2 (Tfh2) cells and T helper 2 (Th2) cells as distinct clusters of differentiation 4+T-cell subsets in settings of type-2 inflammation. Although the transcriptional programs driving Th2 cell differentiation and cytokine production are well defined, dependence on these classical Th2 programs by Tfh2 cells is less clear. Using cytokine reporter mice in combination with transcription factor inference analysis, the b-Zip transcription factor c-Maf and its targets were identified as an important regulon in both Th2 and Tfh2 cells. Conditional deletion of c-Maf in T cells confirmed its importance in type-2 cytokine expression by Th2 and Tfh2 cells. However, while c-Maf was not required for Th2-driven helminth clearance or lung eosinophilia, it was required for Tfh2-driven Immunoglobulin E production and germinal center formation. This differential regulation of cell-mediated and humoral immunity by c-Maf was a result of redundant pathways in Th2 cells that were absent in Tfh2 cells, and c-Maf-specific mechanisms in Tfh2 cells that were absent in Th2 cells. Thus, despite shared expression by Tfh2 and Th2 cells, c-Maf serves as a unique regulator of Tfh2-driven humoral hallmarks during type-2 immunity.

Periodontitis (PD) is a severe inflammatory gum pathology that damages the periodontal soft tissue and bone. It is highly prevalent in the US, affecting more than 47% of adults. Besides routine scaling and root planing, there are few effective treatments for PD. Developed as an effective treatment for hyperlipidemia, simvastatin (SIM) is also known for its well-established anti-inflammatory and osteogenic properties, suggesting its potential utility in treating PD. Its clinical translation, however, has been impeded by its poor water-solubility, lack of osteotropicity, and side effects (e.g., hepatoxicity) associated with systemic exposure. To address these challenges, an N-(2-hydroxypropyl) methacrylamide (HPMA) copolymer-based thermoresponsive polymeric prodrug of SIM (ProGel-SIM) was developed as a local therapy for PD. Its aqueous solution is free-flowing at 4 °C and transitions into a hydrogel at ∼30 °C, allowing for easy local application and retention. After a thorough characterization of its physicochemical properties, ProGel-SIM was administered weekly into the periodontal pocket of an experimental rat model of PD. At 3 weeks post initiation of the treatment, the animals were euthanized with palate isolated for μ-CT and histological analyses. When compared to dose equivalent simvastatin acid (SMA, active form of SIM) treatment, the rats in the ProGel-SIM treated group showed significantly higher periodontal bone volume (0.34 mm3vs 0.20 mm3, P= 0.0161) and less neutrophil (PMN) infiltration (P< 0.0001) and IL-1β secretion (P= 0.0036). No measurable side effect was observed. Collectively, these results suggest that ProGel-SIM may be developed as a promising drug candidate for the effective clinical treatment of PD.

Background:Minocycline microspheres (MMs) are being used to treat residual inflamed periodontal pockets during periodontal maintenance therapy (PMT), but evidence for efficacy from randomized clinical trials is lacking. The purpose of this study is to evaluate the effect of MMs plus scaling and root planing (SRP) on these sites. Methods:Sixty patients with chronic periodontitis on 6‐month PMT intervals to be followed for 1 year were randomized (51 completed the study) into two statistically similar groups, SRP + MM (aged 66.8 years) and SRP alone (aged 67 years), to treat a ≥5 mm posterior interproximal pocket during PMT with a history of bleeding on probing (BOP). Group treatments were applied to the site at baseline and 6 months. Clinical attachment levels (CALs; primary outcome), probing depths (PDs), plaque, and BOP also were recorded at baseline and 6 and 12 months. In addition, gingival crevicular fluid was analyzed for an inflammation index ratio of interleukin (IL)‐1β/IL‐1 receptor antagonist (ra) using enzyme‐linked immunosorbent assays. Results:All clinical parameters improved significantly (P<0.005) from baseline in both groups with no differences between groups at any time point. CAL decreased 17% (0.9 ± 0.8 mm) and 13% (0.7 ± 0.9 mm) in SRP + MM and 11% (0.7 ± 1.1 mm) and 21% (1.2 ± 0.9 mm) in SRP at 6 and 12 months, respectively. The odds of having BOP decreased 90% (down to 38% of patients) and 95% (26%) in SRP + MM and 82% (42%) and 82% (41%) in SRP at 6 and 12 months, respectively. IL‐1β/IL‐1ra decreased a significant 61% (P= 0.009) only in SRP + MM at 6 months. Conclusions:SRP of inflamed moderate pockets during 6‐month PMT, with or without MMs, improves CALs, along with PDs and BOP over a 1‐year period. The use of MMs did not result in an additional benefit over SRP alone.

For several decades, cardiovascular diseasehas been the leading cause of death throughout all countries. There is a strong genetic component to many disease subtypes (e.g., cardiomyopathy) and we are just beginning to understand the relevant genetic factors. Several studies have related RNA splicing to cardiovascular diseaseand circular RNAs(circRNAs) are an emerging player. circRNAs, which originate through back-splicing events from primary transcripts, are resistant to exonucleases and typically not polyadenylated. Initial functional studies show clear phenotypic outcomes for selected circRNAs. We provide, for the first time, a comprehensive catalogue of RNase R-resistant circRNA species for the adult murine heart. This work combines state-of-the-art circle sequencing with our novel DCC software to explore the circRNA landscape of heart tissue. Overall, we identified 575 circRNA species that pass a beta-binomial test for enrichment (false discovery rate of 1%) in the exonuclease-treated sequencing sample. Several circRNAs can be directly attributed to host genes that have been previously described as associated with cardiovascular disease. Further studies of these candidate circRNAs may reveal disease-relevant properties or functions of specific circRNAs.

Background:Local application of statins has shown potential in preventing and regenerating bone loss associated with experimental periodontitis. This study evaluates the effect of a novel simvastatin (SIM) prodrug (capable of delivering high doses to periodontitis inflammatory lesion and cells) on experimental periodontitis bone loss and inflammation. Methods:Forty mature female Sprague Dawley rats were subjected to ligature‐induced experimental periodontitis between maxillary first and second molars (M1‐M2). Equal groups were treated with three weekly doses of: 1) prodrug carrier alone (mPEG); 2) 0.5 mg SIM dose equivalent in carrier (SIM/SIM‐mPEG); 3) 1.0 mg SIM/SIM‐mPEG; 4) 1.5 mg SIM/SIM‐mPEG; or 5) ligature alone. Contralateral molars served as unmanipulated controls. Four weeks after initiation of periodontitis, animals were euthanized, the M1‐M2 interproximal was evaluated with microcomputed tomography and histology, and data were analyzed with one‐way analysis of variance. Results:Ligature alone caused a mean bone loss of 1.01 ± 0.06 mm from the cemento‐enamel junction, whereas all doses of SIM/SIM‐mPEG reduced bone loss, especially 1.5 mg SIM/SIM‐mPEG (0.68 ± 0.05 mm, P<0.001), which was not statistically different from contralateral control (0.47 ± 0.06 mm). A dose of 1.5 mg SIM/SIM‐mPEG also reduced percentage of neutrophils compared with carrier alone (2.0% ± 1.0% versus 5.7% ± 1.1%; P<0.05), and increased amount of uninflamed connective tissue in the M1‐M2 interproximal area (65.2% ± 3.3% versus 46.3% ± 3.3%; P<0.001). The mPEG carrier alone did not have bone‐sparing or anti‐inflammatory properties. Conclusion:Multiple local 1.5‐mg doses of a macromolecular SIM prodrug decreases amount of experimental periodontitis bone loss and inflammation in rats.

Bacteria express many small RNAs for which the regulatory roles in pathogenesis have remained poorly understood due to a paucity of robust phenotypes in standard virulence assays. Here we use a generic ‘dual RNA-seq’ approach to profile RNA expression simultaneously in pathogen and host during Salmonella entericaserovar Typhimurium infection and reveal the molecular impact of bacterial riboregulators. We identify a PhoP-activated small RNA, PinT, which upon bacterial internalization temporally controls the expression of both invasion-associated effectors and virulence genes required for intracellular survival. This riboregulatory activity causes pervasive changes in coding and noncoding transcripts of the host. Interspecies correlation analysis links PinT to host cell JAK–STAT signalling, and we identify infection-specific alterations in multiple long noncoding RNAs. Our study provides a paradigm for a sensitive RNA-based analysis of intracellular bacterial pathogens and their hosts without physical separation, as well as a new discovery route for hidden functions of pathogen genes.

Crew resource management is an important aspect of aircraft management. It is not a mechanical process but an operational philosophy that acknowledges the importance of people and unpredictable situations in the honing of skills. The concept has, unfortunately, been whittled down to a mere procedure devoid of the human element. Airplane pilots should benefit from the application of the concept in its original sense since it has been established that 70% of all accidents have been caused by human factors.

Juvenile idiopathic arthritis (JIA) often causes inflammation of the temporomandibular joint (TMJ) and has been treated with both systemic and intra-articular steroids, with concerns about effects on growing bones. In this study, we evaluated the impact of a macromolecular prodrug of dexamethasone (P-DEX) with inflammation-targeting potential applied systemically or directly to the TMJ. Joint inflammation was initiated by injecting two doses of complete Freund’s adjuvant (CFA) at 1-month intervals into the right TMJs of 24 growing Sprague–Dawley male rats (controls on left side). Four additional rats were not manipulated. With the second CFA injection, animals received (1) 5 mg of P-DEX intra-articularly (n = 9), (2) 15 mg of P-DEX into the tail vein (n = 7), or (3) nothing in addition to CFA (n = 8). The rats were killed 28 days later and measured by radiography for ramus height (condylar superior to gonion inferior [CsGoInf]), by micro-computed tomography for condylar width (CW) and bone volume/standardized condylar volume (BV/CV), and by histology for retrodiscal inflammatory cells. Inflammation targeting of systemic P-DEX was confirmed by IVIS infrared dye imaging. Inflammation and bone growth were compared between groups using analysis of variance and Pearson’s correlations. CFA caused a significant reduction in CsGoInf (p< 0.05), but neither route of P-DEX administration had an effect on CsGoInf or CW at CFA injection sites. BV/CV was significantly reduced in both inflamed and control condyles as a result of either steroid application (p< 0.05). The inflammatory infiltrate was overwhelmingly lymphocytic, comprising 16.4 ± 1.3 % of the field in CFA alone vs. <0.01 % lymphocytes in contralateral controls (p< 0.0001). Both P-DEX TMJ (10.1 ± 1.2 %) and systemic P-DEX (8.9 ± 1.7 %) reduced lymphocytes (p< 0.002). The total area of inflammatory infiltrate was significantly less in the systemic injection group than in the group that received CFA injections alone (2.6 ± 1.5 mm2vs. 8.0 ± 1.3 mm2; p= 0.009), but not in the group that received intra-articular P-DEX (8.8 ± 1.2 mm2). High-dose systemic administration of inflammation-targeting P-DEX is more effective than an intra-articular injection in reducing TMJ inflammation, but both routes may affect TMJ bone density.

The impact of tooth mobility and occlusal trauma (OT) on periodontal bone loss and need for therapy has been debated for many years. This paper summarizes the relevant literature reported in three Dental Clinics of North Americaarticles in the late 1990s, and adds newer information from the 2000s. Principle findings indicate that strong evidence of mobility and OT impacting tooth longevity is lacking, but reducing inflammation in the surrounding periodontium remains a critical treatment. Occlusal therapy when mobility is increasing, comfort or function are compromised, or periodontal regeneration procedures are planned should be considered.

Background:Numerous studies have documented the clinical outcomes of laser therapy for untreated periodontitis, but very few have reported on lasers treating inflamed pockets during maintenance therapy. The aim of this study is to compare the effectiveness of scaling and root planing (SRP) plus the adjunctive use of diode laser therapy to SRP alone on changes in the clinical parameters of disease and on the gingival crevicular fluid (GCF) inflammatory mediator interleukin‐1β (IL‐1β) in patients receiving regular periodontal maintenance therapy. Methods:This single‐masked and randomized, controlled, prospective study includes 22 patients receiving regular periodontal maintenance therapy who had one or more periodontal sites with a probing depth (PD) ≥5 mm with bleeding on probing (BOP). Fifty‐six sites were treated with SRP and adjunctive laser therapy (SRP + L). Fifty‐eight sites were treated with SRP alone. Clinical parameters, including PD, clinical attachment level (CAL), and BOP, and GCF IL‐1β levels were measured immediately before treatment (baseline) and 3 months after treatment. Results:Sites treated with SRP + L and SRP alone resulted in statistically significant reductions in PD and BOP and gains in CAL. These changes were not significantly different between the two therapies. Similarly, differences in GCF IL‐1β levels between SRP + L and SRP alone were not statistically significant. Conclusion:In periodontal maintenance patients, SRP + L did not enhance clinical outcomes compared to SRP alone in the treatment of inflamed sites with ≥5 mm PD.

Background:Simvastatin has been shown to stimulate new bone growth on rat mandibles, but much of the bone is lost over time. The purpose of this study is to evaluate the impact of a locally or systemically applied antiresorptive agent (alendronate) on simvastatin‐induced bone formation in and adjacent to a rat periodontal defect. Methods:Fenestration defects were created over mandibular molar roots in 65 mature female Sprague‐Dawley rats. Two weeks later, animals were divided into eight groups of eight to nine rats, and three weekly injections around the defect were applied: 1) 0.5 mg simvastatin in ethanol (SIM‐EtOH); 2) 0.5 mg simvastatin in alendronate–cyclodextrin conjugate (SIM‐ALN‐CD); 3) EtOH alone; 4) ALN‐CD alone; or 5) no injections. Twenty‐four animals were evaluated for new bone width around the defect 21 days after the last injections (short‐term) and 41 rats were followed for 48 days (long‐term). Three SIM‐EtOH groups of long‐term rats also were subjected to 2 weeks of daily systemic ALN or saline either during or 3 to 4 weeks after SIM‐EtOH injections. Decalcified, hematoxylin‐and‐eosin‐stained cross‐sections of the defect area were analyzed for new bone width and groups were compared using mixed‐model analyses of variance. Results:All groups showed nearly 100% bone fill, with no differences among the short‐term groups. However, in the long‐term animals, two‐fold to three‐fold more new bone width (≤0.004) was seen around the periphery of the defect with the use of systemic ALN after SIM‐EtOH injections (0.93 ± 0.12 and 0.78 ± 0.11 mm with early and late systemic ALN, respectively) compared to local SIM/ALN‐CD preparations (0.32 ± 0.10 mm) or short‐term SIM‐EtOH injections (0.35 ± 0.10 mm). No significant new cementum formation or ankylosis was noted. Conclusion:The use of a short course of systemic ALN during the healing period after bone anabolic SIM injections has the potential to enhance local bone augmentation.

Helicobacter pylori, one of the most prevalent human pathogens, used to be thought to lack small regulatory RNAs (sRNAs) which are otherwise considered abundant in all bacteria. However, our recent analysis of the primary transcriptome of H. pylori discovered an unexpectedly large number of sRNAs, and suggested that this model organism also uses riboregulation to control the expression of its genes. Nonetheless, whereas most enterobacterial sRNAs require the RNA chaperone Hfq for function, Epsilonproteobacteria including H. pyloriseem to have no Hfq homologue, which prompted us to search for other auxiliary proteins in sRNA-mediated regulation. Therefore, we have developed two orthogonal methods to isolate and investigate in vivoand in vitroassembled RNA-protein complexes in H. pylori: (i) an affinity chromatography strategy based on aptamer-tagged sRNAs of interest to identify their protein binding partners; and (ii) a rapid method for chromosomal FLAG-tagging of proteins to facilitate co-immunoprecipitation of associated RNA species. Using these methods, we have identified RNA-protein interactions between the ribosomal protein S1 and various mRNAs and sRNAs of H. pylori. Moreover, both methods reported a stable RNA-protein complex between the abundant HPnc6910 sRNA and HP1334, a protein of unknown function that is encoded downstream of HPnc6910. Given that 50% of all bacteria may lack Hfq, our methods can be useful to identify RNA-protein interactions in a wider range of bacterial pathogens.

Small RNAs (sRNAs) play a pivotal role in bacterial gene regulation. However, the sRNAs of the vast majority of bacteria with sequenced genomes still remain unknown since sRNA genes are usually difficult to recognize and thus not annotated. Here, expression of seven sRNAs (BjrC2a, BjrC2b, BjrC2c, BjrC68, BjrC80, BjrC174 and BjrC1505) predicted by genome comparison of Bradyrhizobiumand Rhodopseudomonasmembers, was verified by RNA gel blot hybridization, microarray and deep sequencing analyses of RNA from the soybean symbiont Bradyrhizobium japonicumUSDA 110. BjrC2a, BjrC2b and BjrC2c belong to the RNA family RF00519, while the other sRNAs are novel. For some of the sRNAs we observed expression differences between free-living bacteria and bacteroids in root nodules. The amount of BjrC1505 was decreased in nodules. By contrast, the amount of BjrC2a, BjrC68, BjrC80, BjrC174 and the previously described 6S RNA was increased in nodules, and accumulation of truncated forms of these sRNAs was observed. Comparative genomics and deep sequencing suggest that BjrC2a is an antisense RNA regulating the expression of inositol-monophosphatase. The analyzed sRNAs show a different degree of conservation in Rhizobiales, and expression of homologs of BjrC2, BjrC68, BjrC1505, and 6S RNA was confirmed in the free-living purple bacterium Rhodopseudomonas palustris5D.

This study investigated the role of the prostaglandin (PG) pathway in locally applied, simvastatin-induced oral bone growth. The possibility of enhancing long-term bone augmentation with an alendronate-based carrier was initiated. Mandibles of 44 mature female rats were treated bilaterally with the following combinations: 2 mg of simvastatin in ethanol (SIM−EtOH), EtOH, 2 mg of simvastatin acid complexed with alendronate−beta-cyclodextrin conjugate (SIM/ALN−CD), ALN−CD, or ALN. Bone wash technology (injection of PBS and re-collection by suction) was used to sample injection sites at baseline (day 0), and 3, 7, 14, and 21 days post-treatment. After 21−24 or 48 days, histomorphometric analysis was done. The amount of PGE2in bone wash fluid was measured by ELISA, normalized by total protein, and compared between high and low bone growth groups (ANOVA) and correlated with subsequent bone histology at 21 days (Spearman). SIM-stimulated PGE2synthase and EP4 receptor mRNA in murine osteoblast and fibroblast cell lines were evaluated with real-time PCR. Single injections of 2 mg of SIM−EtOH induced significantly more new bone than control side after 21 days. PGE2/protein ratios peaked at day 7 and were correlated with the subsequent 21-day new bone width. The correlations at day 14 between PGE2and new bone width changed to a negative relationship in the test group. SIM-stimulated osteoblasts expressed increased mRNA levels of PGE receptor EP4, while SIM activated PGE synthesis in fibroblasts. SIM/ALN−CD tended to preserve bone long-term. Findings suggest that PGE pathway activation and higher levels of PGE2during the first week following SIM-induced bone growth are desirable, and alendronate−beta-cyclodextrin conjugates not only act as tissue-specific carriers, but preserve new bone.

Background:To study aldose reductase and the sorbitol pathway in periodontitis and diabetes, rats with experimental periodontitis with or without diabetes were treated with three structurally diverse aldose reductase inhibitors (ARIs). Methods:Periodontitis was induced with three consecutive palatal injections of Porphyromonas gingivalislipopolysaccharide (LPS) at 48‐hour intervals between the first and second molars on the right side in young, age‐matched, streptozotocin‐induced rats with and without diabetes 44 days after initiation of diets with and without the ARIs tolrestat, imirestat, and quercetin. As an internal control, phosphate‐buffered saline (PBS) was similarly injected on the left side. Twenty‐four days after the final injection, all rats were euthanized. Defleshed samples were stained with 5% toluidine blue and palatal digital images were traced to include the enamel crown and exposed root. The root/enamel ratios (to estimate alveolar bone loss) were analyzed with repeated measures analysis of variance. Results:LPS injections resulted in significantly more bone loss versus PBS injections in both the rats with and without diabetes on normal diets (P<0.0001). All three ARIs significantly reduced LPS‐induced periodontitis in the animals with and without diabetes (P≤0.003) to the level where they were not different from PBS‐injected sites in normal diet controls. Conclusion:All ARIs demonstrated efficacy in preventing alveolar bone loss because of periodontitis in both animals with and without diabetes, suggesting a role for the sorbitol pathway and the potential for ARIs to reduce inflammatory responses downstream from aldose reductase.

Background:Locally injected simvastatin (SIM) has been shown to induce bone growth in rat models. The purpose of this study is to evaluate the effects of locally injected simvastatin in several human‐like clinical situations in a beagle dog model. Methods:Four beagle dogs completed the study and were used in a split‐mouth design. Dehiscence defects of 5 × 3 mm were created bilaterally on the lateral aspect of the mandibular second premolar (PM2) mesial roots including removal of root cementum. At the same surgery, porous hydroxyapatite–collagen grafts with resorbable membranes with or without 10‐mg SIM were placed buccal to the mandibular first molars (M1). One week later, three weekly local injections of 10‐mg SIM in ethanol and contralateral ethanol alone were initiated at three sites through the buccal mucosa: 1) 6 mm apical to the cemento‐enamel junction (CEJ) of the maxillary fourth premolar (PM4; thin bone over root); 2) 6 mm apical to the CEJ of PM2 (dehiscence defect); and 3) 10 mm distoapical to the CEJ of the maxillary canine (edentulous ridge). Dogs were euthanized 2 months after the final injections. Block sections were harvested and specimens were decalcified and stained with hematoxylin and eosin. Histomorphometry was performed using digitized photographs and analyzed with distribution‐free rank tests. Results:Regarding M1, the distance between CEJ and the alveolar crest was significantly more coronal in the SIM group (P= 0.038). Regarding the edentulous ridge, the width of new bone was significantly greater in SIM injection specimens (P= 0.0164). Regarding PM2, buccal bone in the dehiscence defects lacking periosteum was not augmented in the SIM group. Regarding PM4, the total width of bone 5 mm apical to the coronal height of contour (thin buccal bone covering the root) was significantly wider on the SIM side (SIM, 0.63 ± 0.53 mm; contralateral ethanol alone, 0.25 ± 0.19 mm; P= 0.0098). Conclusion:Locally injected SIM has the ability to induce modest amounts of new bone formation in closed injection sites over a periosteal surface.

Periodontitis has been reported to be associated with coronary artery disease (CAD). Research is needed to determine if therapies that improve periodontal health also reduce systemic measures of inflammation associated with both diseases.

Two genes encoding for late embryogenesis abundant proteins (LEAs) are expressed in encysted diapausing embryos (or resting eggs) of rotifers (Brachionus plicatilis O.F. Müller) and females forming them. The two genes (bpa-leaaand bpa-leab)share approximately 50% of their nucleotides sequence, and bpa-leaais more than twofold longer than bpa-leab. The deduced amino acid sequences show high abundance of alanine, glycine, lysine, and glutamic acid; a hydropathy index of lower than one; and a relatively high (81–82%) predicted probability of forming alpha-helices in their secondary structure, all of which are characteristic features of LEAs. The predicted molecular masses of bpa-LEAA (∼67 kDa) and bpa-LEAB (∼27 kDa) are similar to the molecular mass determined by Western-blot analyses, suggesting a low probability of posttranslational modifications. In silico analysis reveals that the two LEAs resemble group 3 LEAs based on the repeats for 11mer motifs, although they also display several putative amino acids typical of the 20mer motif of group 1 LEAs. The rotifer LEAs do not contain a predicted target sequence and are more likely localized in the cytosol. LEAs were expressed in resting eggs and females producing them, but not in other female forms or males. LEA transcripts and proteins are degraded during hatching, suggesting that LEAs are developmentally programmed during resting egg formation and hatching. LEAs probably equip the resting eggs to withstand desiccation if that occurs during dormancy. The present study expands our knowledge about the biological pathways associated with formation of rotifer resting eggs and also demonstrates the occurrence of LEAs in dormant, nondesiccated, encysted animal embryos.

Background:The analysis of biomarkers in gingival crevicular fluid (GCF) may be helpful in forecasting patient vulnerability to future attachment loss. The purpose of this study is to correlate GCF biomarkers of inflammation and bone resorption with subsequent periodontal attachment and bone loss in a longitudinal trial of a matrix metalloproteinase (MMP) inhibitor. Methods:GCF was collected from two periodontal pockets (mean ± SD: 5.1 ± 1.0 mm) at baseline and annually in postmenopausal females with moderate to advanced periodontitis undergoing periodontal maintenance every 3 to 4 months during a 2‐year double‐masked, placebo‐controlled, randomized clinical trial of subantimicrobial dose doxycycline (SDD; 20 mg two times a day). Subjects were randomized to SDD (n = 64) or a placebo (n = 64). GCF was analyzed for the inflammation markers interleukin (IL)‐1β (using enzyme‐linked immunosorbent assay), total collagenase activity (using hydrolysis of a synthetic octapeptide), and MMP‐8 (using a Western blot) and the bone‐resorption marker carboxyterminal telopeptide cross‐link fragment of type I collagen (ICTP) (using a radioimmunoassay). Generalized estimating equations were used to associate these biomarkers, categorized into tertiles, with subsequent clinical attachment (using an automated disk probe) or interproximal bone loss (using radiography). Odds ratio (OR) values compared highest to lowest tertile groups. Results:Increases in GCF IL‐1β and MMP‐8 during the first year of periodontal maintenance were associated with increased odds of subsequent (year 2) periodontal attachment loss (OR = 1.67; P= 0.01 and OR = 1.50; P= 0.02, respectively) driven by the placebo group. Elevated baseline ICTP was also associated with increased odds of 1‐ and 2‐year loss of alveolar bone density (OR = 1.98; P= 0.0001) in the placebo group, not the SDD group, and a loss of bone height (OR = 1.38; P= 0.06), again driven by the placebo group. Conclusion:These data support the hypothesis that elevated GCF biomarkers of inflammation and bone resorption from a small number of moderate/deep sites have the potential to identify patients who are vulnerable to progressive periodontitis, and SDD may modify that risk.

ABSTRACTMaintenance of the effective local concentration of antimicrobials on the tooth surface is critical for the management of cariogenic bacteria in the oral cavity. We report on the design of a simple tooth-binding micellar drug delivery platform that would effectively bind to tooth surfaces. To achieve tooth-binding ability, the chain termini of biocompatible Pluronic copolymers were modified with a biomineral-binding moiety (i.e., alendronate). The micelles formulated with this polymer were shown to be able to swiftly (<1 min) bind to hydroxyapatite (HA; a model tooth surface) and gradually release the encapsulated model antimicrobial (farnesol). These tooth-binding micelles were negatively charged and had an average effective hydrodynamic diameter of less than 100 nm. In vitro biofilm inhibition studies demonstrated that the farnesol-containing tooth-binding micelles were able to provide significantly stronger inhibition of Streptococcus mutansUA159 biofilm formation on HA discs than the untreated blank control micelles (P< 0.0001). Upon further optimization, this delivery platform could provide an effective tool for caries prevention and treatment.

MLL translocations in adult B-cell precursor (BCP) acute lymphoblastic leukemia (ALL) are largely restricted to the immature CD10− immunophenotypes. MLL-AF4 is known to be the most frequent fusion transcript, but the exact frequencies of MLL aberrations in CD10− adult BCP-ALL are unknown. We present a genetic characterization of 184 BCR-ABL− CD10− adult ALL cases (156 cyIg−, 28 cyIg+) diagnosed between 2001 and 2007 at the central diagnostic laboratory of the GMALL study group. Patient samples were investigated by RT-PCR for MLL-AF4, MLL-ENL, and MLL-AF9 and by long-distance inverse polymerase chain reaction, thus also allowing the identification of unknown MLL fusion partners at the genomic level. MLL-AF4 was detected in 101 (54.9%) and MLL-ENL in 11 (6.0%) cases. In addition, rare MLL fusion genes were found: 2 MLL-TET1 cases, not previously reported in ALL, 1 MLL-AF9, 1 MLL-PTD, a novel MLL-ACTN4, and an MLL-11q23 fusion. Chromosomal breakpoints were determined in all 118 positive cases, revealing 2 major breakpoint cluster regions in the MLL gene. Characteristic features of MLL+ patients were significantly lower CD10 expression, expression of the NG2 antigen, a higher white blood count at diagnosis, and female sex. Proposals are made for diagnostic assessment. The clinical studies are registered at http://www.clinicaltrials.gov as NCT00199056 and NCT00198991.

MLLtranslocations in adult B-cell precursor (BCP) acute lymphoblastic leukemia (ALL) are largely restricted to the immature CD10−immunophenotypes. MLL-AF4is known to be the most frequent fusion transcript, but the exact frequencies of MLLaberrations in CD10−adult BCP-ALL are unknown. We present a genetic characterization of 184 BCR-ABL−CD10−adult ALL cases (156 cyIg−, 28 cyIg+) diagnosed between 2001 and 2007 at the central diagnostic laboratory of the GMALL study group. Patient samples were investigated by RT-PCR for MLL-AF4, MLL-ENL, and MLL-AF9and by long-distance inverse polymerase chain reaction, thus also allowing the identification of unknown MLLfusion partners at the genomic level. MLL-AF4was detected in 101 (54.9%) and MLL-ENLin 11 (6.0%) cases. In addition, rare MLLfusion genes were found: 2 MLL-TET1cases, not previously reported in ALL, 1 MLL-AF9, 1 MLL-PTD, a novel MLL-ACTN4, and an MLL-11q23 fusion. Chromosomal breakpoints were determined in all 118 positive cases, revealing 2 major breakpoint cluster regions in the MLLgene. Characteristic features of MLL+patients were significantly lower CD10 expression, expression of the NG2 antigen, a higher white blood count at diagnosis, and female sex. Proposals are made for diagnostic assessment. The clinical studies are registered at http://www.clinicaltrials.govas NCT00199056 and NCT00198991.

Background:We recently demonstrated that a 2‐year subantimicrobial‐dose doxycycline (SDD) regimen (double‐masked, placebo‐controlled clinical trial) in postmenopausal (PM) women exhibiting mild systemic bone loss (osteopenia) and local bone loss (periodontitis) reduced the progression of periodontal attachment loss (intent‐to‐treat analysis) and the severity of gingival inflammation and alveolar bone loss (subgroups) without producing antibiotic side effects. We now describe SDD effects on biomarkers of collagen degradation and bone resorption in the gingival crevicular fluid (GCF) of the same vulnerable subjects. Methods:GCF was collected from SDD‐ and placebo‐treated PM subjects (n = 64 each) at the baseline and 1‐ and 2‐year appointments; the volume was determined; and the samples were analyzed for collagenase activity (using a synthetic peptide as substrate), relative levels of three genetically distinct collagenases (Western blot), a type‐1 collagen breakdown product/bone resorption marker (a carboxyterminal telopeptide cross‐link fragment of type I collagen [ICTP]; radioimmunoassay), and interleukin‐1β (enzyme‐linked immunosorbent assay). Statistical analyses were performed using generalized estimating equations; primary analyses were intent‐to‐treat. Results:Collagenase activity was significantly reduced by SDD treatment relative to placebo based on intent‐to‐treat (P= 0.01). ICTP showed a similar pattern of change during SDD treatment, and GCF collagenase activity and ICTP were positively correlated at all time periods (P<0.001). Matrix metalloproteinase (MMP)‐8 accounted for ∼80% of total collagenase in GCF, with much less MMP‐1 and −13, and SDD reduced the odds of elevated MMP‐8 by 60% compared to placebo (P= 0.006). Conclusion:These observations support the therapeutic potential of long‐term SDD therapy to reduce periodontal collagen breakdown and alveolar bone resorption in PM women; effects on serum biomarkers of systemic bone loss in these subjects are being analyzed.

Background:Topical injection of simvastatin in methylcellulose gel was shown to stimulate bone growth and inflammation over mouse calvaria and in rat mandible models. The purpose of these pilot studies was to evaluate the potential of locally injected simvastatin in human‐sized periodontal defects. Methods:Chronic periodontal defects were created bilaterally in seven 1‐year‐old beagle dogs: 3‐walled intrabony defects distal of the mandibular second premolar and mesial of the fourth premolar and Class II furcation defects at the buccal furcation of the mandibular first molars. The edentulous space distal to the mandibular canine was left undisturbed. After 16 weeks of healing, defect sites were treated with scaling and root planing, and mandible sides were randomly selected to receive three weekly injections of 0.5 mg simvastatin in 30 μl methylcellulose gel and contralateral gel alone (n = 3) or 2.0 mg simvastatin/methylcellulose gel and contralateral gel alone (n = 4). Two months following drug application, block sections, including teeth and surrounding tissues, and submandibular lymph nodes were obtained for histomorphometric analysis. Results:Two trends were noted in this pilot study: buccal edentulous ridge thickness was 29% greater with simvastatin, 0.5 mg, compared to gel alone (P= 0.0845), and the simvastatin groups had bone‐height loss in interproximal intrabony and furcation defects, but the length of new cementum in the interproximal intrabony defects was greater with simvastatin, 0.5 mg (0.35 ± 0.14 mm), compared to gel alone (0.06 ± 0.15 mm; P= 0.069). No new cementum was found in furcations. Conclusions:Multiple injections of simvastatin are not appropriate for the treatment of intrabony or furcation defects. However, this approach shows potential to augment bone thickness in closed alveolar environments.

Background:Based on microbiologic concerns, the safety of a 24‐month regimen of subantimicrobial dose doxycycline (SDD; 20 mg twice a day) was evaluated in postmenopausal osteopenic women with periodontitis in a double‐blind, placebo‐controlled, randomized clinical trial. Methods:Subgingival samples were collected from two sites (probing depth ≥5 mm) in each of 128 subjects at baseline, with the same sites resampled at the conclusion of the 2‐year period. The samples were enumerated on selective and non‐selective media and on doxycycline (4 μg/ml) medium. Up to five different colonial morphologies were subcultured from the doxycycline medium, identified to species, and susceptibilities determined to doxycycline and five other antibiotics. Data were analyzed for microbial differences in total colony forming units (CFU), periodontal and opportunistic pathogens, and changes in species and in susceptibilities of isolates recovered on doxycycline medium. Results:There was no significant evidence that changes in total anaerobic counts over the treatment period (P= 0.96) differed between treatment groups. Likewise, periodontal pathogens, opportunistic pathogens, or normal flora did not differ descriptively between groups. Although there was a significant increase (P<0.001) in the total CFU recovered from the 4 μg/ml doxycycline plates at 24 months for SDD versus placebo, the percentage that was clinically resistant to doxycycline (minimal inhibitory concentration [MIC] ≥16 μg/ml) decreased over the 24‐month period in both groups and did not differ between the treatment groups (SDD: 79% to 76%; placebo: 83% to 70%; P= 0.2). There were no significant differences (P>0.28 for each) in the change in cross‐resistance between the groups for doxycycline and the other five antibiotics. Conclusions:No antimicrobial effect on the subgingival flora was detected following treatment with SDD for 24 months, relative to baseline or to placebo. The increase in initial resistance (at 4 μg/ml) did not translate into a significant increase in the percent resistant to doxycycline (MIC ≥16 μg/ml) for patients in the SDD group.