Cone-Beam Computed Tomography for Objective Diagnosis of Age-Related Soft Tissue Changes in Lower Face and Neck.

BACKGROUND: An objective assessment of the causes of age-related contour deformities of the soft tissues of the face and neck is very important in esthetic surgery, especially as minimally invasive techniques gain increasing popularity. METHODS: To visualize the tissues that cause age-related soft tissue changes, we performed cone-beam computed tomography (CBCT) in 37 patients who underwent facial and neck rejuvenation procedures in 2021-2022. RESULTS: Vertical CBCT enabled visualization of the causes and degree of tissue involvement in age-related changes in the lower third of the face and neck. CBCT showed the location and condition of the platysma (hypo- [ptosis], normo-, or hyper-tonus), position, thickness, and location (above and/or below the platysma) of fat tissue, presence of ptosis of the submandibular salivary glands, condition of the anterior bellies of the digastric muscles, and the degree of their participation in contours of the cervicomandibular angle, and location of the hyoid bone. Moreover, CBCT enabled demonstrating for the patient the facial and neck contour deformations and discussing the suggested corrective methods using a clear objective visual image. CONCLUSIONS: CBCT in the upright position enables objective assessment of each soft tissue in the age-related deformity of the cervicofacial region and provides an opportunity to plan the appropriate impact on the particular anatomical structures during rejuvenation procedures and estimate their results. This is the only study to date to objectively and clearly visualize the entire topographic anatomy of the soft tissues of the face and neck vertically for plastic surgeons and patients. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Synthesis and Characterization of Phosphorus-Containing Isocyclam Macrocycles and Their Nickel Complexes.

The tetradentate azamacrocycle cyclam (=1,4,8,11-tetraazacyclotetradecane) was studied profoundly for the coordination of transition metal ions, and the resulting complexes were investigated extensively for their catalytic performance in, e.g., O2 activation and electrocatalytic CO2 reduction. Although the successful synthesis of analogous P4 macrocycles was described earlier, no tetradentate N,P mixed 14-membered macrocycles have been prepared to date and their chemistry remains elusive. Thus, in this work, we showcase the synthesis of phospha-aza mixed cyclam-based macrocycles by selectively "exchanging" one or two secondary amines in the macrocycle isocyclam (=1,4,7,11-tetraazacyclotetradecane) with tertiary phosphines. In addition, we herein present the preparation of the corresponding nickel complexes along with their complex chemical and structural characterization to provide first coordination studies.

Zwitterionic Peptides Reduce Accumulation of Marine and Freshwater Biofilm Formers.

Zwitterionic peptides are facile low-fouling compounds for environmental applications as they are biocompatible and fully biodegradable as their degradation products are just amino acids. Here, a set of histidine (H) and glutamic acid (E), as well as lysine (K) and glutamic acid (E) based peptide sequences with zwitterionic properties were synthesized. Both oligopeptides (KE)4K and (HE)4H were synthesized in d and l configurations to test their ability to resist the nonspecific adsorption of the proteins lysozyme and fibrinogen. The coatings were additionally tested against the attachment of the marine organisms Navicula perminuta and Cobetia marina as well as the freshwater bacterium Pseudomonas fluorescens on the developed coatings. While the peptides containing lysine performed better in protein resistance assays and against freshwater bacteria, the sequences containing histidine were generally more resistant against marine organisms. The contribution of amino acid-intrinsic properties such as side chain pKa values and hydrophobicity, as well as external parameters such as pH and salinity of fresh water and seawater on the resistance of the coatings is discussed. In this way, a detailed picture emerges as to which zwitterionic sequences show advantages in future generations of biocompatible, sustainable, and nontoxic fouling release coatings.