Creation and Validation of a Photonumeric Scale for Assessment of Infraorbital Hollows.

BACKGROUND: Validated clinical scales are needed to assess aesthetic improvement of the infraorbital hollows (IOHs) after treatment with dermal fillers. OBJECTIVE: To develop an IOHs scale and establish its reliability and sensitivity for grading subjects in clinical trials or routine practice. METHODS AND MATERIALS: The Teoxane IOHs Scale (TIOHS), a 5-grade photonumeric scale, was developed based on real-subject photographs and validated through photographic and live subjects' evaluation. RESULTS: Clinician intra- and inter-rater agreements during the TIOHS validation were excellent. The mean intrarater-weighted Kappa score between the 2 sessions of photographic validation was 0.92, while inter-rater interclass correlation coefficient (ICC) was 0.92 for the combined sessions. The average intrarater-weighted Kappa score and inter-rater ICC for the live validation reached 0.80 and 0.76, respectively. In addition, evaluators identified clinically significant differences between photographs of subjects presenting a 1-grade or 2-grade difference in 82% and 86% of cases, respectively. CONCLUSION: The intrarater Kappa scores and inter-rater ICCs met their predetermined acceptance criteria of >0.70. The TIOHS is a repeatable and reproducible clinician-reported outcome for health care providers to classify IOHs in clinical trials and routine patient care. A 1-grade difference on the TIOHS can detect a clinically meaningful difference in infraorbital hollowing.

Injection Guidelines for Treating Midface Volume Deficiency With Hyaluronic Acid Fillers: The ATP Approach (Anatomy, Techniques, Products).

Midface rejuvenation is among the most valuable indications of hyaluronic acid dermal fillers, because malar projection and full upper cheeks significantly contribute to a youthful appearance. Hyaluronic acid fillers have evolved over the past 2 decades to meet specific clinical needs such as strong projection capacity and adaptability to facial dynamism. As a result, they now represent the treatment of choice for midface rejuvenation throughout age ranges by offering the potential for noninvasive treatment, immediate results, and minimal downtime. Because the 5-layered structure of the midface plays a central role in the human face, injecting the midface area may also indirectly improve other aesthetic concerns such as infraorbital hollowing and nasolabial folds. Nonetheless, midface rejuvenation requires a tailored treatment approach and a thorough knowledge of anatomy to minimize procedural risks and achieve natural-looking results. This article provides an extensive anatomical description of the midface and of the usual course and depth of vascular structures circulating nearby to delineate a treatment area and minimize procedural risks. Furthermore, considering the differential mobility and mechanical constraints of each layer of the midface, a multilayer treatment algorithm is proposed for adapting the treatment strategy to patient specificities (including age, gender, skin type, and morphology). Emphasis is also placed on desirable filler properties to create deep structural support on the one hand and accompany facial movement on the other hand.

Hybrid Cell-Penetrating Foldamer with Superior Intracellular Delivery Properties and Serum Stability.

Sequence specific molecules with high folding ability (i.e., foldamers) can be used to precisely control the distribution and projection of side chains in space and have recently been introduced as tailored systems for delivering nucleic acids into cells. Designed oligourea sequences with an amphipathic distribution of Arg- and His-type residues were shown to form tight complexes with plasmid DNA, and to effectively promote the release of DNA from the endosomes. Herein, we report the synthesis of new cell-penetrating foldamer sequences in which the foldamer segment is conjugated via a reducible disulfide bond to a ligand that binds cell-surface expressed nucleoproteins with the idea that this system could facilitate both assemblies with nucleic acids and cell entry. This new system was evaluated for delivery of DNA in several cell lines and was found to compare favorably with all comparators tested (DOTAP and b-PEI as well as a number of known cell penetrating peptides) in various cell lines and particularly in culture medium containing up to 50% of serum. These results suggest that this dual molecular platform which is long lasting and noncytotoxic could be of practical use for in vivo applications.

Postelongation Strategy for the Introduction of Guanidinium Units in the Main Chain of Helical Oligourea Foldamers.

The synthesis of hybrid urea-based foldamers containing isosteric guanidinium linkages at selected positions in the sequence is described. We used a postelongation approach whereby the guanidinium moiety is introduced by direct transformation of a parent oligo(urea/thiourea) foldamer precursor. The method involves activation of the thiourea by treatment with methyl iodide and subsequent reaction with amines. To avoid undesired cyclization with the preceding urea moiety, resulting in heterocyclic guanidinium formation in the main chain, the urea unit preceding the thiourea unit in the sequence was replaced by an isoatomic and isostructural γ-amino acid. The approach was extended to solid-phase techniques to accelerate the synthesis of longer and more functionalized sequences. Under optimized conditions, an octamer hybrid oligomer incorporating a central guanidinium linkage was obtained in good overall yield and purity. This work also reports data related to the structural consequences of urea by guanidinium replacements in solution and reveals that helical folding is substantially reduced in oligomers containing a guanidinium group.

Effect of replacing main-chain ureas with thiourea and guanidinium surrogates on the bactericidal activity of membrane active oligourea foldamers.

Membrane-active foldamers have recently emerged as potential mimics of antimicrobial peptides (AMPs). Amphiphilic cationic helical N,N'-linked oligoureas are one such class of AMP mimics with activities in vitro against a broad range of bacteria including Bacillus anthracis, a Gram-positive sporulating bacillus and causing agent of anthrax. Here we have used site-selective chemical modifications of the oligourea backbone to gain additional insight into the relationship between structure and function and modulate anthracidal activity. A series of analogues in which urea linkages at selected positions are replaced by thiourea and guanidium surrogates have been prepared on solid support and tested against different bacterial forms of B. anthracis (germinated spores and encapsulated bacilli). Urea→thiourea and urea→guanidinium replacements close to the negative end of the helix dipole led to analogues with increased potency and selectivity for B. anthracis versus mammalian cells.

Isosteric substitutions of urea to thiourea and selenourea in aliphatic oligourea foldamers: site-specific perturbation of the helix geometry.

Nearly isosteric oxo to thioxo substitution was employed to interrogate the structure of foldamers with a urea backbone and explore the relationship between helical folding and hydrogen-bonding interactions. A series of oligomers with urea bonds substituted by thiourea bonds at discrete or all positions in the sequence have been prepared and their folding propensity was studied by using a combination of spectroscopic methods and X-ray diffraction. The outcome of oxo to thioxo replacements on the helical folding was found to depend on whether central or terminal ureas were modified. The canonical helix geometry was not affected upon insertion of thioureas close to the negative end of the helix dipole, whereas thioureas close to the positive pole were found to increase the terminal flexibility and cause helix fraying. Perturbation was amplified when a selenourea was incorporated instead, leading to a structure that is only partly folded.

A cell-penetrating foldamer with a bioreducible linkage for intracellular delivery of DNA.

Despite significant advances in foldamer chemistry, tailored delivery systems based on foldamer architectures, which provide a high level of control over secondary structure, are curiously rare among non-viral technologies for transporting nucleic acids into cells. A potent pH-responsive, bioreducible cell-penetrating foldamer (CPF) was developed through covalent dimerization of a short (8-mer) amphipathic oligourea sequence bearing histidine-type units. This CPF exhibits a high capacity to assemble with pDNA and mediates efficient delivery of nucleic acids into the cell. Furthermore, it does not adversely affect cellular viability and was shown to compare favorably with a cognate peptide transfection agent based on His-rich sequences.

Creation and validation of a photonumeric scale for assessment of lip fullness.

BACKGROUND: Validated, objective clinical scales are needed to assess aesthetic improvement of the lips after augmentation with dermal fillers. OBJECTIVE: To develop a lip fullness rating scale and establish its reliability for grading subjects in clinical trials or routine practice, and sensitivity for detecting clinically meaningful changes. METHODS: The Teoxane Lip Fullness Scale (TLFS), a proprietary, 5-grade photonumeric scale, was developed by clinical experts based on real subject photographs and was validated through both photographic and live subjects' evaluation. RESULTS: Clinician intra- and inter-rater agreement for the TLFS was substantial to almost perfect. Mean intra-rater weighted Kappa score between the two rounds of photographic validation was 0.92, and inter-rater agreement was substantial with an ICC of 0.93 for the combined rounds. Average intra-rater weighted Kappa score and inter-rater ICC for the live validation were equally high, reaching 0.91 and 0.89 respectively. Additionally, evaluators identified clinically significant differences between photographs of subjects presenting a 1-grade or 2-grade difference on the scale in 90% and 98% of cases, respectively. CONCLUSIONS: The intra-rater Kappa scores and inter-rater ICC met their pre-determined acceptance criteria of >0.70 in the photographic and live validation. The TLFS was shown to be a repeatable and reproducible Clinician Reported Outcome (Clin-RO) for healthcare providers to classify lip fullness both in clinical trials and in routine patient care. A 1-grade difference on the TLFS can detect a clinically meaningful difference in lip fullness.

Proteolytically Stable Foldamer Mimics of Host-Defense Peptides with Protective Activities in a Murine Model of Bacterial Infection.

The synthesis of bioinspired unnatural backbones leading to foldamers can provide effective peptide mimics with improved properties in a physiological environment. This approach has been applied to the design of structural mimics of membrane active antimicrobial peptides (AMPs) for which activities in vitro have been reported. Yet activities and pharmacokinetic properties in vivo in animal models have remained largely unexplored. Here, we report helical oligourea AMP mimics that are active in vitro against bacterial forms of Bacillus anthracis encountered in vivo, as well as in vivo in inhalational and cutaneous mouse models of B. anthracis infection. The pharmacokinetic profile and the tissue distribution were investigated by ß-radio imager whole-body mapping in mice. Low excretion and recovery of the native oligourea in the kidney following intravenous injection is consistent with high stability in vivo. Overall these results provide useful information that support future biomedical development of urea-based foldamer peptide mimics.

The proline-rich antimicrobial peptide Onc112 inhibits translation by blocking and destabilizing the initiation complex.

The increasing prevalence of multidrug-resistant pathogenic bacteria is making current antibiotics obsolete. Proline-rich antimicrobial peptides (PrAMPs) display potent activity against Gram-negative bacteria and thus represent an avenue for antibiotic development. PrAMPs from the oncocin family interact with the ribosome to inhibit translation, but their mode of action has remained unclear. Here we have determined a structure of the Onc112 peptide in complex with the Thermus thermophilus 70S ribosome at a resolution of 3.1 Å by X-ray crystallography. The Onc112 peptide binds within the ribosomal exit tunnel and extends toward the peptidyl transferase center, where it overlaps with the binding site for an aminoacyl-tRNA. We show biochemically that the binding of Onc112 blocks and destabilizes the initiation complex, thus preventing entry into the elongation phase. Our findings provide a basis for the future development of this class of potent antimicrobial agents.