Results suggest that the two-layered dissolving microneedles are useful as an immediate-release transdermal DDS for peptide/protein drugs.

No abstract

There are no national data available of the oral health in Myanmar. In this study, we examined dental caries status of 187 school children located in the suburban area of Naypyidaw, capital of Myanmar, at the age of five and six and analyzed by the individual level and tooth level. Maxillary D and B were sensitive for dental caries almost at the same level. They were less sensitive than maxillary A. Mandibular A and B were tolerant for dental caries. Prevalence of dental caries in Myanmar children was still high. By applying item response theory and multilevel modeling, tooth level analysis can be implemented to confirm the tendency for sensitivity or tolerance for dental caries by the tooth level.

Dissolving microneedles were demonstrated to be a useful TDDS as an immediate-acting insulin preparation.

No abstract

Transdermal drug delivery systems (TDDS) have been challenged to increase the permeation rate of drugs through the skin and experimental strategies have included the use of chemical enhancers and physical methods. Of these, chemical enhancers have contributed most to the development of TDDS. Approximately 20 products of TDDS were launched on the US market by the end of 2008. Thus the penetration of small molecules through the skin can be enhanced by chemical enhancers.1) However, triggering of skin irritation and other safety concerns limit their use. As examples of physical absorption enhancement methods, iontophoresis, electroporation, and ultrasound have been investigated.2-6) Iontophoresis uses an electric field to drive ionized molecules across the skin by electrophoresis and nonionized molecules by electroosmosis. Despite concerns about skin irritation, iontophoresis may be useful for delivery of some peptides including insulin. 7) In particular, TDDS of lidocaine by iontophoresis was launched onto the US market in 2004. Also, transient enhancement of skin permeability of both small drugs and macromolecules has been shown by electroporation and ultrasound. 8,9) Recent advances in microfabrication technology have made it possible to prepare microneedles that have a possible application as novel TDDS. Since the first publication by Henry et al. 10) in 1998, microfabrication techniques for the production of silicon, metal, glass and polymer microneedle arrays with micrometer dimensions have been reported. [11][12][13][14] The microneedles are either solid or hollow and possess a geometrical shape. Microneedle TDDS are roughly defined by a micron-sized needle preparation through and by which drug is percutaneously administered. Microneedle TDDS are classified as follows: (1) extremely small needles through which drug solution can be injected into the skin; (2) metallic and/or silastic microneedles on whose surface drug is coated; and (3) metallic and/or silastic microneedles with which conduits (micropores) are made on the skin and drug solution is applied after removing the microneedles. Fully to understand the function of microneedles, the physiology of the skin must be considered. There are no blood vessels in the epidermis. Deeper, there are blood capillaries in the dermis, which forms the bulk of skin volume and contains living cells and nerves. When microneedle arrays are inserted into the skin, conduits are created for the penetration of drug across stratum corneum (SC). Once a drug penetrates the SC, it can diffuse rapidly through the deeper tissue and permeate into the underlying capillaries for systemic absorption.Our previous studies suggest that macromolecules such as insulin, 15,16) erythropoietin (EPO), 17,18) interferon, 19) and recombinant human growth hormone 20) are well absorbed through rat skin by self-dissolving micropile preparations about 2-3 mm in length with an outer diameter of 0.3-0.4 mm. In addition, a self-dissolving micropile array (SDMA), comprising 10 lines and 10 columns, was...

In developing countries, the prevalence of dental caries in children remains high, which means that implementing a simple and convenient classification is critical. The classification needs to be evidence-based and needs to reflect tooth-level information. In this study, the prevalence of dental caries in the primary dentition of 352 Myanmar school children at the ages of 5, 6, and 7 was analyzed at the tooth level to clarify the underlying data structure of the patterns of dental caries in the population. Ninety-three percent of subjects had caries in primary dentition and the mean number of decayed teeth in primary dentition was 7.54 ± 4.82. Based on the item response theory analysis, mixed-effect modeling, and Bayesian network analysis, we proposed the following classification: Group 1: No dental caries; Group 2: Dental caries in molar teeth or dental caries in maxillary anterior teeth; Group 3: Dental caries in both molar and maxillary anterior teeth; Group 4: Dental carries in mandibular anterior teeth. Dental caries (dmft) in the groups was different between groups. The results of characteristics of tooth-level information and classification presented in this study may be a useful instrument for the analysis of the data of dental caries prevalence in primary dentition.

Several studies have shown that the oral microbiome is related to systemic health, and a co-relation with several specific diseases has been suggested. The oral microbiome depends on environmental- and community-level factors. In this observational study, the oral microbiomes of children of isolated mountain people were analyzed with respect to the core oral microbiome and etiology of dental caries. We collected samples of supragingival plaque from children (age 9–13) living in the Chin state of Myanmar. After DNA extraction and purification, next-generation sequencing of the V3–V4 hypervariable regions of the 16S rRNA was conducted. From thirteen subjects, 263,458 valid reads and 640 operational taxonomic units were generated at a 97% identity cut-off value. At the phylum level, Proteobacteria was the most abundant, followed by Firmicutes and Bacteroides. Forty-four bacteria were detected in total from all the subjects. For children without dental caries, Proteobacteria was abundant. In contrast, in children with dental caries, Firmicutes and Bacteroides were abundant. The oral microbiome of children living in an isolated area may be affected by environmental- and community-level factors. Additionally, the composition of the oral microbiome may affect the risk of dental caries.