Melanocortin-1 receptor (MC1R) genotypes do not correlate with size in two cohorts of medium-to-giant congenital melanocytic nevi.

Congenital melanocytic nevi (CMN) are cutaneous malformations whose prevalence is inversely correlated with projected adult size. CMN are caused by somatic mutations, but epidemiological studies suggest that germline genetic factors may influence CMN development. In CMN patients from the U.K., genetic variants in MC1R, such as p.V92M and loss-of-function variants, have been previously associated with larger CMN. We analyzed the association of MC1R variants with CMN characteristics in two distinct cohorts of medium-to-giant CMN patients from Spain (N = 113) and from France, Norway, Canada, and the United States (N = 53), similar at the clinical and phenotypical level except for the number of nevi per patient. We found that the p.V92M or loss-of-function MC1R variants either alone or in combination did not correlate with CMN size, in contrast to the U.K. CMN patients. An additional case-control analysis with 259 unaffected Spanish individuals showed a higher frequency of MC1R compound heterozygous or homozygous variant genotypes in Spanish CMN patients compared to the control population (15.9% vs. 9.3%; p = .075). Altogether, this study suggests that MC1R variants are not associated with CMN size in these non-UK cohorts. Additional studies are required to define the potential role of MC1R as a risk factor in CMN development.

Evaluation of 5-year-old children with complete cleft lip and palate: Multicenter study. Part 2: Functional results.

BACKGROUND AND PURPOSE: Cleft surgery is marked by all the controversies and the multiplication of protocols, as it has been shown by the Eurocleft study. The objective of this pilot study is to start a comparison and analyzing procedure between primary surgical protocols in French centers. METHODS: Four French centers with different primary surgical protocols for cleft lip and palate repair, have accepted to be involved in this retrospective study. In each center, 20 consecutive patients with complete cleft lip and palate (10 UCLP, 10 BCLP per center), non syndromic, have been evaluated at a mean age of 5 [range, 4-6]. In this second part, maxillary growth and palatine morphology were assessed on clinical examination and on dental casts (Goslon score). Speech was also evaluated clinically (Borel-maisonny classification) and by Aerophonoscope. RESULTS: Veau-Wardill-Killner palatoplasty involves a higher rate of transversal maxillary deficiency and retromaxillary. The fistula rate is statistically lower with tibial periosteum graft hard palate closure but this technique seems to give retromaxillary. Malek and Talmant two-stage-palatoplasty techniques reach Goslon scores of 1 or 2. Considering speech, Sommerlad intravelar veloplasty got higher outcomes. CONCLUSIONS: Primary results. Extension to other centers required. The two-stage palatoplasty, including a Sommerlad intravelar veloplasty seems to have the less negative impact on maxillary growth, and to give good speech outcomes. LEVEL OF EVIDENCE: Therapeutic study. Level III/retrospective multicenter comparative study.

Evaluation of 5-year-old children with complete cleft lip and palate: Multicenter study. Part 1: Lip and nose aesthetic results.

BACKGROUND AND PURPOSE: Cleft surgery is marked by all the controversies and the multiplication of protocols, as it has been shown by the Eurocleft study. The objective of this pilot study is to start a comparison and analyzing procedure between primary surgical protocols in French centers. METHODS: Four French centers with different primary surgical protocols for cleft lip and palate repair, have accepted to be involved in this retrospective study. In each center, 20 consecutive patients with complete cleft lip and palate (10 UCLP and 10 BCLP per center), non syndromic, have been evaluated at a mean age of 5 [4,6]. In this first part, the aesthetic results of nose and lip repair were assessed based on the scale established by Mortier et al. (1997). RESULTS: Considering nose outcome, primary cleft repair surgery including a nasal dissection gives a statistically significant benefit in terms of septum deviation. Considering lip result, muscular dehiscence rate is significantly higher in BCLP patients with a two-stage lip closure. The centers using Millard one-stage lip closure do not have uniform results. For UCLP patients, the quality of scar is not statistically different between Skoog and Millard techniques. CONCLUSIONS: Primary results based on a simple, reproducible evaluation protocol. Extension to other centers required. LEVEL OF EVIDENCE: Therapeutic study. Level III/retrospective multicenter comparative study.

Absence of the major light-harvesting antenna proteins alters the redox properties of photosystem II reaction centres in the chlorina F2 mutant of barley.

Although the chlorina F2 mutant of barley specifically exhibits reduced levels of the major light-harvesting polypeptides associated with photosystem II (PSII), thermoluminescence measurements of photosystem reaction centre photochemistry revealed that S2/S3QB- charge recombinations were shifted to lower temperatures, while the characteristic peak of S2QA- charge recombinations was shifted to higher temperatures compared with wild-type (WT) barley. Thus, we show that the absence of the major light-harvesting polypeptides affects the redox properties of PSII reaction centres. Radiolabeling studies in vivo and in vitro with [32P]orthophosphate or [gamma-32P]ATP, respectively, demonstrated that the D1 PSII reaction centre polypeptide is phosphorylated in both the WT and the F2 mutant. In contrast with the radiolabeling results, phosphorylation of D1 and other PSII proteins, although detected in WT barley, was ambiguous in the F2 mutant when the phosphothreonine antibody method of detection was used. Thus, caution must be exercised in the use of commercially available phosphothreonine antibodies to estimate thylakoid polypeptide phosphorylation. Furthermore, in membrano, the D1 polypeptide of the F2 mutant was less susceptible to trypsin treatment than that of WT barley. The role of the light-harvesting complex in modulating the structure and function of the D1 polypeptide of PSII reaction centers is discussed.

Nitric oxide donor-mediated inhibition of phosphorylation shows that light-mediated degradation of photosystem II D1 protein and phosphorylation are not tightly linked.

An outcome of the photochemistry during oxygenic photosynthesis is the rapid turn over of the D1 protein in the light compared to the other proteins of the photosystem II (PS II) reaction center. D1 is a major factor of PS II instability and its replacement a primary event of the PS II repair cycle. D1 also undergoes redox-dependent phosphorylation prior to its degradation. Although it has been suggested that phosphorylation modulates D1 metabolism, reversible D1 phosphorylation was reported not to be essential for PS II repair in Arabidopsis. Thus, the involvement of phosphorylation in D1 degradation is controversial. We show here that nitric oxide donors inhibit in vivo phosphorylation of the D1 protein in Spirodela without inhibiting degradation of the protein. Thus, D1 phosphorylation is not tightly linked to D1 degradation in the intact plant.

Phosphorylation of the D1 photosystem II reaction center protein is controlled by an endogenous circadian rhythm.

The light dependence of D1 phosphorylation is unique to higher plants, being constitutive in cyanobacteria and algae. In a photoautotrophic higher plant, Spirodela oligorrhiza, grown in greenhouse conditions under natural diurnal cycles of solar irradiation, the ratio of phosphorylated versus total D1 protein (D1-P index: [D1-P]/[D1] + [D1-P]) of photosystem II is shown to undergo reproducible diurnal oscillation. These oscillations were clearly out of phase with the period of maximum in light intensity. The timing of the D1-P index maximum was not affected by changes in temperature, the amount of D1 kinase activity present in the thylakoid membranes, the rate of D1 protein synthesis, or photoinhibition. However, when the dark period in a normal diurnal cycle was cut short artificially by transferring plants to continuous light conditions, the D1-P index timing shifted and reached a maximum within 4 to 5 h of light illumination. The resultant diurnal oscillation persisted for at least two cycles in continuous light, suggesting that the rhythm is endogenous (circadian) and is entrained by an external signal.