Enhancing children's participation in dental research: A commentary.

The concept of childhood has evolved over the years, inspired by the United Nations Convention on the Rights of the Child in 1989, shifting from developmental models to a conception of childhood that recognizes children as moral agents. This evolution highlights the importance of respecting children's agency and their right to be heard in matters that are related to them. In conventional health research, however, children's voices are often inadequately accessed. In this commentary, we discuss the imperative to recognize children's agency in dental research and a shift from research on children to research with and by children. Moreover, we underscore the importance of actively seeking and listening to children's voices and recognizing their agency in shaping research and healthcare practices in the field of dentistry. Further, we explore the application of participatory research approaches in dental research and provide examples of studies that have involved children in various capacities. We conclude this commentary by emphasizing the potential benefits of participatory research in both qualitative and quantitative dental studies to promote deeper understanding, clearer communication, and stronger advocacy regarding children's interests. Primarily, we call for greater recognition of children's agency in dental research and advocate for more inclusive and child-centred research methodologies.

Damage in transition.

Double-stranded DNA breaks (DSBs) are a particularly dangerous form of DNA damage because they can lead to chromosome loss, translocations or truncations. When DSBs occur, many proteins are recruited to the break site; these proteins serve to both initiate DNA repair and to activate a checkpoint response. Repair occurs via one of two pathways: non-homologous end-joining (NHEJ), in which broken DNA ends are directly ligated; or homologous recombination (HR), in which a homologous chromosome is used as a template in a replicative repair process. The checkpoint response is mediated by the phosphatidyl inositol 3-kinase-like kinases, Mec1 and Tel1 (ATR and ATM in humans, respectively). Two recent studies in yeast have significantly increased our understanding of when each of the proteins involved in these processes is localized to a break and, in addition, how their sequential localization is achieved. Specifically, these studies support and expand upon a model in which Tel1 and the NHEJ proteins are the first proteins to localize to the break to initiate signaling and attempt repair, but are subsequently replaced by Mec1 and the HR proteins. This transition is mediated by a cyclin-dependent kinase-dependent initiation of 5'-->3' processing (resection) of the DSB. Thus, the cell-cycle stage at which DSBs occur affects the way in which the DSBs are processed and recognized.

Morphological characteristics of skeletal muscles in relation to gender.

BACKGROUND AND AIMS: The aim of this study was to ascertain whether there are gender-related differences in the morphological characteristics of the soleus and tibialis anterior muscles in young adult and old Fischer 344/Brown Norway F1 rats. METHODS: We tested 1) whether there was a gender-related difference between the fiber type composition of these muscles, and 2) whether the cross-sectional area of individual muscle fibers demonstrated gender-associated differences, fibers from males being larger than fibers from females. RESULTS: Gender differences were not found in the fiber type composition of the soleus and tibialis anterior muscles, but were present in the single skeletal fiber cross-sectional area of the tibialis anterior muscle. The cross-sectional area of type I fibers in females was greater than that in males at both 12 (16%) and 30 (5%) months of age. In contrast, the cross-sectional area of type Ila fibers of 12-month-old males was larger than that of 12-month-old females. No significant differences between genders were found for the cross-sectional area of type Ilb fibers in either age group. In the soleus muscle, 30-month-old males had larger single fiber cross-sectional areas of both fiber types I and lIa. At 12 months of age, type I fibers from females were larger than those from males. CONCLUSIONS: Our findings indicate that gender-related differences exist in the size of individual skeletal fibers from the soleus and tibialis anterior muscles and that they may influence metabolism and the adaptive response to rehabilitation programs.

Overlapping roles of the spindle assembly and DNA damage checkpoints in the cell-cycle response to altered chromosomes in Saccharomyces cerevisiae.

The MAD2-dependent spindle checkpoint blocks anaphase until all chromosomes have achieved successful bipolar attachment to the mitotic spindle. The DNA damage and DNA replication checkpoints block anaphase in response to DNA lesions that may include single-stranded DNA and stalled replication forks. Many of the same conditions that activate the DNA damage and DNA replication checkpoints also activated the spindle checkpoint. The mad2Delta mutation partially relieved the arrest responses of cells to mutations affecting the replication proteins Mcm3p and Pol1p. Thus a previously unrecognized aspect of spindle checkpoint function may be to protect cells from defects in DNA replication. Furthermore, in cells lacking either the DNA damage or the DNA replication checkpoints, the spindle checkpoint contributed to the arrest responses of cells to the DNA-damaging agent methyl methanesulfonate, the replication inhibitor hydroxyurea, and mutations affecting Mcm2p and Orc2p. Thus the spindle checkpoint was sensitive to a wider range of chromosomal perturbations than previously recognized. Finally, the DNA replication checkpoint did not contribute to the arrests of cells in response to mutations affecting ORC, Mcm proteins, or DNA polymerase delta. Thus the specificity of this checkpoint may be more limited than previously recognized.