Single Layer Transdermal Film Containing Lidocaine: Water and Lidocaine Mobility Determined using Neutron Scattering

The diffusivity of lidocaine through a polymer film developed for transdermal drug administration has been characterized by macroscopic permeation experiments and by neutron quasielastic spectroscopy that provides information on microscopic diffusivity parameters. It turns out that film hydration plays a key role on the performance and efficiency of the investigated system. Diffusion of lidocaine, at the microscopic level, is triggered by the presence of “mobile water.” At hydration levels below 15% (weight water/weight hydrated film) neither lidocaine nor water show any appreciable long-range diffusion. At higher hydration levels, the onset of water long-range diffusion triggers diffusion of lidocaine through the film. The use of neutron quasielastic scattering makes it possible to measure lidocaine mobility within the film without the need of any additional physical barrier.     

Natural human knockouts and Mendelian disorders: deep phenotyping in Italian isolates

Whole genome sequencing (WGS) allows the identification of human knockouts (HKOs), individuals in whom loss of function (LoF) variants disrupt both alleles of a given gene. HKOs are a valuable model for understanding the consequences of genes function loss. Naturally occurring biallelic LoF variants tend to be significantly enriched in “genetic isolates,” making these populations specifically suited for HKO studies. In this work, a meticulous WGS data analysis combined with an in-depth phenotypic assessment of 947 individuals from three Italian genetic isolates led to the identification of ten biallelic LoF variants in ten OMIM genes associated with known autosomal recessive diseases. Notably, only a minority of the identified HKOs (C7, F12, and GPR68 genes) displayed the expected phenotype. For most of the genes, instead, (ACADSB, FANCL, GRK1, LGI4, MPO, PGAM2, and RP1L1), the carriers showed none or few of the signs and symptoms typically associated with the related diseases. Of particular interest is a case presenting with a FANCL biallelic LoF variant and a positive diepoxybutane test but lacking a full Fanconi anemia phenotypic spectrum. Identifying KO subjects displaying expected phenotypes suggests that the lack of correct genetic diagnoses may lead to inappropriate and delayed treatment. In contrast, the presence of HKOs with phenotypes deviating from the expected patterns underlines how LoF variants may be responsible for broader phenotypic spectra. Overall, these results highlight the importance of in-depth phenotypical characterization to understand the role of LoF variants and the advantage of studying these variants in genetic isolates.Subject terms: Genetics research, DNA sequencing, Rare variants     

Molecular analysis of a human PAX6 homeobox mutant

Pax6 controls eye, pancreas and brain morphogenesis. In humans, heterozygous PAX6 mutations cause aniridia and various other congenital eye abnormalities. Most frequent PAX6 missense mutations are located in the paired domain (PD), while very few missense mutations have been identified in the homeodomain (HD). In the present report, we describe a molecular analysis of the human PAX6 R242T missense mutation, which is located in the second helix of the HD. It was identified in a male child with partial aniridia in the left eye, presenting as a pseudo-coloboma. Gel-retardation assays revealed that the mutant HD binds DNA as well as the wild-type HD. In addition, the mutation does not modify the DNA-binding properties of the PD. Cell transfection assays indicated that the steady-state levels of the full length mutant protein are higher than those of the wild-type one. In cotransfection assays a PAX6 responsive promoter is activated to a higher extent by the mutant protein than by the wild-type protein. In vitro limited proteolysis assays indicated that the presence of the mutation reduces the sensitivity to trypsin digestion. Thus, we suggest that the R242T human phenotype could be due to abnormal increase of PAX6 protein, in keeping with the reported sensitivity of the eye phenotype to increased PAX6 dosage.     

Mutations in a new cytochrome P450 gene in lamellar ichthyosis type 3

We report the identification of mutations in a non-syndromic autosomal recessive congenital ichthyosis (ARCI) in a new gene mapping within a previously identified locus on chromosome 19p12-q12, which has been defined as LI3 in the OMIM database (MIM 604777). The phenotype usually presents as lamellar ichthyosis and hyperlinearity of palms and soles. Seven homozygous mutations including five missense mutations and two deletions were identified in a new gene, FLJ39501, on chromosome 19p12 in 21 patients from 12 consanguineous families from Algeria, France, Italy and Lebanon. FLJ39501 encodes a protein which was found to be a cytochrome P450, family 4, subfamily F, polypeptide 2 homolog of the leukotriene B4-omega-hydroxylase (CYP4F2) and could catalyze the 20-hydroxylation of trioxilin A3 from the 12(R)-lipoxygenase pathway. Further oxidation of this substrate by the fatty alcohol:nicotinamide-adenine dinucleotide oxidoreductase (FAO) enzyme complex, in which one component, ALDH3A2, is known to be mutated in Sj?gren-Larsson syndrome (characterized by ichthyosis and spastic paraplegia), would lead to 20-carboxy-(R)-trioxilin A3. This compound could be involved in skin hydration and would be the essential missing product in most forms of ARCI. Its chiral homolog, 20-carboxy-(S)-trioxilin A3, could be implicated in spastic paraplegia and in the maintenance of neuronal integrity.     

Use of microvascular free flaps in the reconstruction of the anterior and middle skull base

Different reconstruction techniques of the anterior and middle skull base as consequence of a defect after surgical treatment of neoplastic pathologies are described in the literature. The aim of the present study is to present our experience regarding the use of microvascular free flaps for reconstruction of the anterior or middle skull base after large defects caused by removal of malignant neoplasms. From 2000 to 2004, in the Department of Maxillo-Facial Surgery of the University of Rome "La Sapienza" and "Tor Vergata," 13 surgical procedures for reconstruction of anterior and middle skull base defects by free flaps were performed in 11 patients. Data on patient demographics, histopathology, location and size of defect, type of reconstruction, and postoperative complications were obtained from medical record charts. A safe soft tissue closure of the intracranial space was achieved in all patients. Defect repair was accomplished by revascularized transfer of rectus abdominis flaps in seven cases, latissimus dorsi muscle flaps in two patients, radial forearm flap in one case, and fibula flap in one case. There were two total flap losses; the secondary defect repair was accomplished in both cases by revascularized transfer of latissimus dorsi muscle flap. No donor site complications were observed in all the flaps. The mean operation time was 85 hours; patients were hospitalized for a mean period of 14 days. The method of choice for the reconstruction of anterior or middle skull base defect should be based upon careful evaluation of the single case and, particularly, the localization and entity of the residual defect. For defects that require large amounts of soft tissue, the latissimus dorsi free flap and the rectus abdominis free flap are the best appropriate choices for reconstructive procedures for anterior and middle skull base tumors.     

Extraction treatment using Invisalign Technique

The Invisalign method is gaining an increasing interest as an alternative treatment option in adult patients and in difficult orthodontic cases. The aim of this work is to show a class II malocclusion with severe crowding in the upper and lower arches treated with the extraction of the upper first premolars performed by means of Invisalign. The alignment phase was successfully completed but the space closure achieved with crown tipping and without correct root inclination making a further fixed appliance phase necessary.     

Assessing the appropriateness and increasing the yield of renal angiography in patients undergoing coronary angiography: a scoring system

The real appropriateness and yield of a coincident renal angiography in patients undergoing coronary angiography is still a matter of debate. We have attempted to defined a scoring system to assess the need for renal angiography in patients undergoing diagnostic coronary angiography. We retrospectively reviewed our invasive cardiology database searching for patients underwent coincident screening abdominal aorta angiography to detect occult renal artery stenosis were analyzed and entry in a development set. Univariate and multivariate logistic regression analyses were employed to determine independent predictors of extra-cardiac atherosclerotic involvement. Based on the odds ratio, identified variables were assigned to a weighted integer; the sum of integers was a total score. Thus, the scoring model was tested on a validation set based on a prospective series of consecutive patients enrolled on the basis of an identified cut-off score. In the development set (635 patients, mean age 68±11.2 years) an angiographically significant RAS was observed in 20% of cases (128 patients). The rate of significant angiographic findings increased proportionally with increasing risk score (Pearson coefficient 0.98). A score of ≥5 was identified to be the cut-off beyond which renal angiography seems to have a sufficiently good efficacy in detecting clinically significant renal artery diseases (‰>‰30% of patients). In the validation set the patients were enrolled on the basis of the identified cut-off score (317 patients, mean age 69±14.1 years): angiographic occult RAS was diagnosed in 156/317 (49.2%) patients of the validation set versus 128/635 (20%) patients of the development set, p<0.01. This scoring system, once applicated in standard medium–high volume cath labs, may be effective in increasing the yield of renal artery angiography in patients undergoing coronary angiography.