Specialized pro‐resolving lipid mediators in experimental periodontitis: A systematic review

Recently, several studies demonstrated the potential of using specialized pro‐resolving lipid mediators (SPMs), as a novel approach, in treating periodontitis in pre‐clinical models. This review aimed to systematically evaluate the biological actions of SPMs on periodontal tissues in animals with experimentally induced periodontitis. This systematic review was performed by following the Preferred Reporting Items for Systematic Reviews and Meta‐Analyses (PRISMA) guidelines. Studies were searched in three databases. Meta‐analysis was not performed because of the data heterogeneity. Study quality was assessed using Systematic Review Centre for Laboratory Animal Experimentation (SYRCLE) Risk of Bias tool. Six studies using an experimental periodontitis model to test the efficacy of SPMs were selected. Resolvin E1 and lipoxins were topically applied to treat experimental periodontitis. Alveolar bone loss could be significantly prevented and regenerated by applying SPMs, when compared to the control group. The dosages of SPMs and the periods of disease induction varied based on the pre‐clinical model employed. Two studies further demonstrated the positive shift in microbial composition, in line with positive shift in inflammatory status, that are regulated by SPMs. Clinical studies are needed to optimize the application of SPMs in treating periodontal diseases in humans.     

Tracking the Phylogeny of Seagrasses: Inferred from 18S rRNA Gene and Ancestral State Reconstruction of Morphological Data

Taxonomic challenges of seagrasses were met by using 18S ribosomal subunit of ribosomal deoxyribonucleic acid (18S rDNA) sequence data of 14 seagrass species from India and two temperate species from Germany. The phylogenetic trees presented are based on the 18S rDNA sequence analysis of 41 nucleotide sequences including sequences obtained in the present study as well as previously published sequences of freshwater and saltmarsh plants, and seagrasses for identifying the evolutionary lineage. The 18S rDNA data indicates independent origin of temperate and tropical seagrasses with the genus Halophila as the intermediate group for both the regions. Based on the complex morphological structures the Halophila group represents the basal form among seagrasses whereas Enhalus is considered to be the most recently originated seagrass species. In that context, the marine Hydrocharitaceae group of Enhalus, Thalassia and Halophila has been proposed to be separated into two groups such as Enhalus/Thalassia and Halophila subfamilies. Hence, the present systematic studies warrant a revised taxonomy for seagrasses, which better reflects the phylogenetic results obtained from molecular and conventional data.     

Differential modulation of sodium- and chloride-dependent opioid peptide transport system by small nonopioid peptides and free amino acids

We recently identified a novel opioid peptide transport system in the retinal pigment epithelium that transports opioid peptides by a Na+/Cl--dependent process. Here we describe a similar transport system expressed in SK-N-SH cells (a human neuronal cell line) and show for the first time that the activity of the transport system is modulated differentially by lysine and small nonopioid peptides. The transport process in SK-N-SH cells, monitored with deltorphin II as the substrate, is Na+/Cl--dependent and interacts with several opioid peptides, consisting of 5 to 13 amino acids. The activity of this transport system is markedly stimulated by specific dipeptides and tripeptides, with significant stimulation observable at low micromolar concentrations. The ion dependence, Na+/Cl--activation kinetics, and opioid peptide selectivity of the transport system, however, remain unchanged. The stimulation by the modulatory peptides is associated with an increase in maximal velocity with no change in substrate affinity of the system. Amino acids have no or little effect on the transport system, with the exception of lysine. This cationic amino acid inhibits the transport system, with significant inhibition occurring at physiologic concentrations of the amino acid. The inhibitory effect is primarily associated with a decrease in the maximal velocity of the transport system with little change in substrate affinity. Methyl and ethyl esters of lysine retain the inhibitory potency, but most other structural analogs have no effect. The differential modulation of the transport system by lysine and specific small peptides has important implications in the biology and pharmacology of opioid peptides.     

Bone changes in leprosy patients with disabilities/deformities (a clinico-radiological correlation).

One hundred and ten leprosy patients (96 males and 14 females, mean age 45.3 years) with disabilities/deformities were examined radiologically to evaluate bone changes and correlating them with clinical parameters. Most patients (98) had paucibacillary leprosy. The mean duration of leprosy was 7.4 years and that of deformity was 4.1 years. Ten patients presented with reaction. Seventy-five (68.2%) patients had received a full course of antileprosy treatment. The overall prevalence of bone changes was 87.3% (96 patients); specific, non-specific, osteoporotic and facial changes were seen in 44.5%, 75.5%, 38.2% and 9.1% of the patients respectively. Among the specific bone changes, primary periosteitis (28.2%) and "bone cysts" (22.7%) were the more common findings. Among the non-specific bone changes, terminal phalangeal absorption (48.2%), soft tissue changes (44.5%) and concentric absorption (32.7%) were more common. Specific bone changes showed a significant (P < 0.05) increase with lack of or incomplete antileprosy treatment. Non-specific bone changes showed significant correlation (P < 0.05) with increasing duration of disease, lack of or partial treatment and rising disability index. Osteoporotic changes showed a significant relationship with rising disability index.