Doxorubicin-loaded polyphosphate glass microspheres for transarterial chemoembolization.

The standard of care for intermediate stage hepatocellular carcinoma is transarterial chemoembolization (TACE). Drug-eluting bead TACE (DEB-TACE) has emerged as a leading form of TACE, as it uses highly calibrated microspheres to deliver consistent embolization and controlled drug release to the tumor microenvironment. We report here on doxorubicin (DOX)-loaded polyphosphate glass microspheres (PGM) as a novel resorbable, radiopaque, preloaded DEB-TACE platform. Coacervate composed of polyphosphate chains complexed with Ba2+ , Ca2+ , and Cu2+ can be loaded with DOX prior to PGM synthesis, with PGM production achieved using a water-in-oil emulsion technique at room temperature yielding highly spherical particles in clinically relevant size fractions. In vitro, DOX release was found to be linear, pH dependent, and in accordance with Type II non-Fickian transport. PGM degradation was characterized by an initial burst release of degradation products over 7 days, followed by a plateau in mass loss at approximately 75% over a period of several weeks. in vitro studies indicate that PGM degradation products, namely Cu2+ , are cytotoxic and may interact with eluted DOX to impair its pharmacological activity. With additional compositional considerations, this approach may prove promising for DEB-TACE applications.

The oral health of ageing baby boomers: a comparison of adults aged 45-64 and those 65 years and older.

OBJECTIVES: To compare the oral health status of adults aged 45-64 (baby boomers) and those aged 65 and older. METHODS: An observational, cross-sectional survey of adults living independently in rural and urban settings in Nova Scotia, Canada was conducted. Using random digit dialing, calibrated interviewers completed a telephone survey, and clinicians calibrated to WHO standards conducted clinical examinations. Weighting was used to correct for sampling bias. RESULTS: 747 community dwelling adults completed both the clinical exam and the questionnaire (n=411, age 45-64; n=336, age 65 or older). Rates of edentulism were low (2.6% aged 45-64; 15.7% aged 65+; p<0.001). Untreated root caries was greater in the older dentate group (19.7 vs. 10.1%; p<0.001). Being 65 years of age or older was identified as a predictor of increased decayed, missing, filled teeth, presence of decayed and/or filled roots and presence of attachment loss≥4 mm, but was not a significant predictor of presence of untreated coronal caries. CONCLUSIONS: A falling rate of edentulism and a higher risk for root caries with increasing age may predict the need for more complex dental care as our population ages.

Oral health status of long-term care residents-a vulnerable population.

OBJECTIVE: To conduct an observational, cross-sectional survey of the oral health status of adults ≥ 45 years of age in rural and urban long-term care (LTC) facilities in Nova Scotia, Canada. METHODS: Residents capable of informed consent were recruited by LTC staff in a stratified random sample of LTC facilities. Calibrated personnel administered standard clinical and quality-of-life instruments. RESULTS: Of the 335 adults (74% female) surveyed (mean age 80.8 ± 11.6 years), only 25% reported having regular dental care. Although 76% described their oral health as good or excellent, 41% were edentulous, 41% had some mucosal abnormality, 36% reported xerostomia and 25% had perceived or self-reported untreated dental conditions. Most mandibular dentures were nonretentive (59%) and almost half were unstable (49%). Among the dentate, 51% had untreated coronal caries, 44% had untreated root caries and 67% had attachment loss of ≥ 4 mm at ≥ 1 site. Predictors of coronal decay were a debris score ≥ 2 (adjusted odds ratio [adj OR] = 2.12; p = 0.045) or a history of smoking (adj OR = 1.02 per year of smoking; p = 0.024). Predictors of root caries were participants' perceiving a need for dental treatment (adj OR = 2.56; p = 0.015) or a history of smoking (adj OR = 1.02 per year of smoking; p = 0.026). CONCLUSIONS: This epidemiologic study of the oral health of LTC residents revealed a high prevalence of untreated oral disease and low use of oral care services, highlighting the need for better access to oral care for this population.

Assessing the oral health of an ageing population: methods, challenges and predictors of survey participation.

OBJECTIVES: To examine predictors of participation and to describe the methodological considerations of conducting a two-stage population-based oral health survey. METHODS: An observational, cross-sectional survey (telephone interview and clinical oral examination) of community-dwelling adults aged 45-64 and ≥65 living in Nova Scotia, Canada was conducted. RESULTS: The survey response rate was 21% for the interview and 13.5% for the examination. A total of 1141 participants completed one or both components of the survey. Both age groups had higher levels of education than the target population; the age 45-64 sample also had a higher proportion of females and lower levels of employment than the target population. Completers (participants who completed interview and examination) were compared with partial completers (who completed only the interview), and stepwise logistic regression was performed to examine predictors of completion. Identified predictors were as follows: not working, post-secondary education and frequent dental visits. CONCLUSION: Recruitment, communications and logistics present challenges in conducting a province-wide survey. Identification of employment, education and dental visit frequency as predictors of survey participation provide insight into possible non-response bias and suggest potential for underestimation of oral disease prevalence in this and similar surveys. This potential must be considered in analysis and in future recruitment strategies.

Compaction strategies for modifying the drug delivery capabilities of gelled calcium polyphosphate matrices.

Calcium polyphosphates (CPPs) have shown potential as drug delivery matrices, particularly in treating bone-related chronic diseases such as osteomyelitis, where maintenance of sufficient bactericidal concentrations at the infected bone site is essential. The objective of this study was to incorporate an additional compaction step as part of a gelling protocol to optimize CPP matrix properties while enhancing their drug delivery capabilities. Vancomycin-loaded CPP powders were produced using a previously established gelling and drying protocol, G1, and then subsequently compacted at prescribed levels (30, 113 or 452MPa) before subjecting to an additional gelling and drying protocol (G2). The resulting G2 disks were found to be more homogeneous and dense (p=0.0013) when compared with corresponding G1 disks, though increases in matrix density did not translate into subsequent increases in tensile strength. The compaction regelling protocol did, however, eliminate the burst release phenomena observed with the G1 disks and further extended the release of vancomycin into a clinically acceptable therapeutic range of 3weeks. These changes were associated with the increase in visual homogeneity, the increase in density and a more homogenous dispersion of vancomycin within the G2 disks. The ability to modulate this release profile to a limited extent by altering compaction stress, particle size distribution and regelling time was also demonstrated. Overall, the compaction regelling protocol described here, when used in conjunction with an initial gelling step to achieve matrix drug loading, enhances the flexibility and long-term drug delivery capability of this CPP matrix.