Throughout the world, there have been drastic decline in mortality rate in pediatric leukemic population due to early diagnosis and improvements in oncology treatment. The pediatric dentist plays an important role in the prevention, stabilization, and treatment of oral and dental problems that can compromise the child's health and quality of life during, and follow up of the cancer treatment. This manuscript discusses recommendations and promotes dental care of the pediatric leukemic patients.

Previous research has shown that penicillin-binding proteins (PBPs), enzymes involved in peptidoglycan (PG) assembly, could play an important role during the induction of viable but non-culturable (VBNC) state, which allows non-spore forming bacteria to survive adverse environmental conditions. The current study found that C. michiganensis has a total of seven PBP proteins. Mutant analysis indicated that deletion of either of the class B PBPs was lethal, and that the class A PBP, PBPC, had an important role in PG synthesis, with the ΔpbpC mutant having an altered cellular morphology that resulted in longer cells that were swollen at one end, and had thinner cell walls. The ΔpbpC mutant was also found to produce mucoid colonies in solid culture and a lower final cell titer in liquid medium, as well as having increased sensitivity to osmotic stress and lysozyme treatment, and surprisingly increased pathogenicity. The double mutant, ΔdacB/ΔpbpE also had a slightly altered phenotype resulting in longer cells. Further analysis revealed that both mutants had increased sensitivity to copper, which resulted in quicker induction into the VBNC state. However, only the ΔpbpC mutant had significantly reduced survivorship in the VBNC state. The study also confirmed the VBNC state significantly improved the survivorship of wild-type C. michiganensis cells in response to environmental stresses, and systemically demonstrated the protective role of the VBNC state in C. michiganensis, which is an important finding regarding its epidemiology, and has serious implications for disease management.

Clavibacter michiganensis is the causal agent of bacterial canker of tomato, which causes significant economic losses because of the lack of resistant tomato varieties. Chemical control with streptomycin or cupric bactericides is the last defensive line in canker disease management. Streptomycin is an aminoglycoside antibiotic that inhibits protein synthesis and targets the 30S ribosomal protein RpsL. Streptomycin has been used to control multiple plant bacterial diseases. However, identification and characterization of streptomycin resistance in C. michiganensis have remained unexplored. In this study, a naturally occurring C. michiganensis strain TX-0702 exhibiting spontaneous streptomycin resistance was identified, with a minimum inhibitory concentration of 128 μg/ml. Additionally, an induced streptomycin-resistant strain BT-0505-R was generated by experimental evolution of the sensitive C. michiganensis strain BT-0505. Genome sequencing and functional analyses were used to identify the genes conferring resistance. A point mutation at the 128th nucleotide in the rpsL gene of strain BT-0505-R is responsible for conferring streptomycin resistance. However, in TX-0702, resistance is not attributed to mutation of rpsL, streptomycin inactivation enzymes, or multidrug efflux pumps. The mechanism of resistance in TX-0702 is independent of previously reported bacterial loci. Taken together, these data highlight diverse mechanisms used by a Gram-positive plant pathogenic bacterium to confer antibiotic resistance.

Xanthomonas campestris pv. campestris (Xcc) is a typical seedborne phytopathogenic bacterium that causes large economic losses worldwide, and this is the first original research article to investigate the role of ppGpp in this important species. Here, we revealed the function of RelA and SpoT in ppGpp production, physiology, pathogenicity, and stress resistance in Xcc.

Lichen planus (LP) is a chronic inflammatory mucocutaneous condition which is relatively common in adults but rarely affects children. The present study is a report on an unusual case of ulcerative oral LP involving the dorsum of tongue in a 12-year-old boy. Patient complained of painful oral lesion on the tongue which was burning in nature and obstructing talking and eating spicy foods. On intraoral examination, a white ulcerative lesion on the dorsum of tongue was observed. Diagnosis was made based on clinical examination and histopathological features. We instituted local treatment and patient responded well to the treatment. Although rarely reported in childhood, lichen planus should be considered in a differential diagnosis of hyperkeratotic, reticular, and ulcerative lesions of the oral mucosa in children.