Fractionated Ablation With Trans-Epidermal Pigment Release: A Novel Tattoo Removal Method.

Tattoos continue to be an important way of emotional and/or identity expression for individuals and communities, whether obtained at a tattoo parlor or through communal rituals. Tattoos vary in their complexity, artistic skill, and overall satisfaction; however, in later years many regret the design, color choice, or the idea of a tattoo altogether. Given the uptick in patients wishing for tattoo removal, various techniques have been developed using energy-based devices such as lasers and destructive methods utilizing caustic chemicals or excision. These modalities come with limitations including incomplete tattoo removal, scarring, and dispersion of tattoo dyes into the lymphatics. Considering these limitations, other treatment modalities for tattoo removal must be explored. In this article, we discuss a new technique for tattoo removal using fractionated ablation of tattoo pigment with trans-epidermal pigment release.  J Drugs Dermatol. 2023;22(11):1103-1106     doi:10.36849/JDD.7250.

A high-content neuron imaging assay demonstrates inhibition of prion disease-associated neurotoxicity by an anti-prion protein antibody.

There is an urgent need to develop disease-modifying therapies to treat neurodegenerative diseases which pose increasing challenges to global healthcare systems. Prion diseases, although rare, provide a paradigm to study neurodegenerative dementias as similar disease mechanisms involving propagation and spread of multichain assemblies of misfolded protein ("prion-like" mechanisms) are increasingly recognised in the commoner conditions such as Alzheimer's disease. However, studies of prion disease pathogenesis in mouse models showed that prion propagation and neurotoxicity can be mechanistically uncoupled and in vitro assays confirmed that highly purified prions are indeed not directly neurotoxic. To aid development of prion disease therapeutics we have therefore developed a cell-based assay for the specific neurotoxicity seen in prion diseases rather than to simply assess inhibition of prion propagation. We applied this assay to examine an anti-prion protein mouse monoclonal antibody (ICSM18) known to potently cure prion-infected cells and to delay onset of prion disease in prion-infected mice. We demonstrate that whilst ICSM18 itself lacks inherent neurotoxicity in this assay, it potently blocks prion disease-associated neurotoxicity.

Prion protein monoclonal antibody (PRN100) therapy for Creutzfeldt-Jakob disease: evaluation of a first-in-human treatment programme.

BACKGROUND: Human prion diseases, including Creutzfeldt-Jakob disease (CJD), are rapidly progressive, invariably fatal neurodegenerative conditions with no effective therapies. Their pathogenesis involves the obligate recruitment of cellular prion protein (PrPC) into self-propagating multimeric assemblies or prions. Preclinical studies have firmly validated the targeting of PrPC as a therapeutic strategy. We aimed to evaluate a first-in-human treatment programme using an anti-PrPC monoclonal antibody under a Specials Licence. METHODS: We generated a fully humanised anti-PrPC monoclonal antibody (an IgG4κ isotype; PRN100) for human use. We offered treatment with PRN100 to six patients with a clinical diagnosis of probable CJD who were not in the terminal disease stages at the point of first assessment and who were able to readily travel to the University College London Hospital (UCLH) Clinical Research Facility, London, UK, for treatment. After titration (1 mg/kg and 10 mg/kg at 48-h intervals), patients were treated with 80-120 mg/kg of intravenous PRN100 every 2 weeks until death or withdrawal from the programme, or until the supply of PRN100 was exhausted, and closely monitored for evidence of adverse effects. Disease progression was assessed by use of the Medical Research Council (MRC) Prion Disease Rating Scale, Motor Scale, and Cognitive Scale, and compared with that of untreated natural history controls (matched for disease severity, subtype, and PRNP codon 129 genotype) recruited between Oct 1, 2008, and July 31, 2018, from the National Prion Monitoring Cohort study. Autopsies were done in two patients and findings were compared with those from untreated natural history controls. FINDINGS: We treated six patients (two men; four women) with CJD for 7-260 days at UCLH between Oct 9, 2018, and July 31, 2019. Repeated intravenous dosing of PRN100 was well tolerated and reached the target CSF drug concentration (50 nM) in four patients after 22-70 days; no clinically significant adverse reactions were seen. All patients showed progressive neurological decline on serial assessments with the MRC Scales. Neuropathological examination was done in two patients (patients 2 and 3) and showed no evidence of cytotoxicity. Patient 2, who was treated for 140 days, had the longest clinical duration we have yet documented for iatrogenic CJD and showed patterns of disease-associated PrP that differed from untreated patients with CJD, consistent with drug effects. Patient 3, who had sporadic CJD and only received one therapeutic dose of 80 mg/kg, had weak PrP synaptic labelling in the periventricular regions, which was not a feature of untreated patients with sporadic CJD. Brain tissue-bound drug concentrations across multiple regions in patient 2 ranged from 9·9 µg per g of tissue (SD 0·3) in the thalamus to 27·4 µg per g of tissue (1·5) in the basal ganglia (equivalent to 66-182 nM). INTERPRETATION: Our academic-led programme delivered what is, to our knowledge, the first rationally designed experimental treatment for human prion disease to a small number of patients with CJD. The treatment appeared to be safe and reached encouraging CSF and brain tissue concentrations. These findings justify the need for formal efficacy trials in patients with CJD at the earliest possible clinical stages and as prophylaxis in those at risk of prion disease due to PRNP mutations or prion exposure. FUNDING: The Cure CJD Campaign, the National Institute for Health Research UCLH Biomedical Research Centre, the Jon Moulton Charitable Trust, and the UK MRC.

A Retrospective and Anatomical Study Describing the Injection of Botulinum Neurotoxins in the Depressor Anguli Oris.

SUMMARY: The depressor anguli oris acts to lower the lateral corners of the mouth and can cause an individual to appear sad or angry and contribute to the development of the labiomental folds. Many patients can benefit from the injection of small amounts of botulinum neurotoxin into the depressor anguli oris to enable the lip elevators to reposition the corners of the mouth. Although effective, the procedure is off-label, and the proximity of the depressor anguli oris to the depressor labii inferioris, particularly inferiorly, can lead to inadvertent treatment of the latter, resulting in lip asymmetry. The authors have taken a threefold approach to establish a depressor anguli oris injection technique that provides optimal aesthetic outcomes with a low incidence of adverse events. This involved, first, reviewing the limited existing literature for studies discussing depressor anguli oris anatomy and botulinum neurotoxin treatment technique; second, supplementing information from the published literature with information from cadaver dissections to demonstrate the relationship between the depressor anguli oris and surrounding anatomical structures; and third, performing a retrospective chart review of 275 patients treated with the authors' three-point injection technique. Combining data from published studies, cadaver dissections, and clinical experience, the authors demonstrate that a three-point technique performed in the upper half of the depressor anguli oris is associated with good clinical outcome and avoids common side effects related to injection or spread of neurotoxin to adjacent muscles. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.

Nonsurgical Chin and Jawline Augmentation Using Calcium Hydroxylapatite and Hyaluronic Acid Fillers.

The shape of the jawline from the mandibular angle to its most forward point at the chin has a profound effect on an individual's appearance and is an area of concern for many seeking esthetic procedures. Dermal filler injections alone or in combination with other modalities, such as skin tightening energy devices, allow enhancement of the jawline while avoiding the need for surgical procedures. The authors introduce new anatomical zones and nomenclature to enhance safety and outcome when enhancing the jawline. Cadaver dissections were performed to better understand landmarks and potential risks and a topographic guide proposed to assist clinicians to create an esthetically pleasing jawline. Techniques for jawline rejuvenation with calcium hydroxylapatite (CaHA) and high G prime hyaluronic acid (HA) fillers are described. When considered as an esthetic unit, the jawline can be broken down into masseteric, buccal, and mental zones, each with their own injection protocols and safety considerations. Dermal fillers suitable for jawline rejuvenation include either CaHA with or without integral lidocaine, a high G prime HA filler, or a hybrid mixture of CaHA and HA, depending on the desired esthetic outcome and the individual's needs. Small volumes of product per injection point achieve the most natural esthetic outcome and minimize serious adverse events. With these techniques, the angle of the mandible is better defined, the pre- and postjowl hollows are filled, and as a result the jawline appears visibly straighter. CaHA and high G prime HA fillers are effective nonsurgical treatments for redefining the mandibular angle and straightening the contour of the jaw. For optimal results, the jawline should be considered as an esthetic unit and careful consideration paid to anatomical landmarks that influence efficacy and safety.

Pathogenic significance of SCN1A splicing variants causing Dravet syndrome: Improving diagnosis with targeted sequencing for variants by in silico analysis.

OBJECTIVES: Genetic heterogeneity of epileptic encephalopathy (IEE) mandates the use of gene-panels for diagnosis. PATIENTS AND METHODS: A 36-gene-panel next-generation sequencing was applied for IEE in two Iranian families. A literature search was performed using keywords to identify reported splicing mutations in SCN1A and perform genotype-phenotype correlation. RESULTS: An update of splicing mutations revealed 147 variants with 65.75% of them de novo mutations. Most of the familial variants were of parental origin. The structure of the protein was often affected in the linker and transmembrane segments. 92% of intronic variants were pathogenic. A de novo heterozygous mutation was found in the first patient, but not in her sibling and parents. In the second family, a novel de novo heterozygous mutation was found at position c.1210insT leading to a truncated protein. CONCLUSION: Gene-panel sequencing is helpful for reducing the time and cost, guiding early treatment, and estimating the recurrence risks. The importance of characterization of intronic variants was noticed; though bioinformatics analysis of novel intronic variants should be of concern for rapid reporting the pathogenic effect of variants.

A blinded, randomized, split-face pilot study of bruising and pain with hyaluronic acid for correction of perioral lines using no lidocaine, lidocaine alone, and lidocaine and epinephrine.

BACKGROUND: Hyaluronic acid (HA) fillers are sometimes mixed with lidocaine to mitigate pain. Whether the addition of epinephrine to lidocaine provides greater benefits in bruising and pain has not been fully reported. OBJECTIVES: The investigators explored the severity of bruising and pain in patients treated with the cohesive polydensified matrix HA (CPMHA) in 3 different preparations: CPMHA (Belotero Balance [BEL]), CPMHA with lidocaine (BEL-L), and CPMHA with lidocaine and epinephrine (BEL-LE). METHODS: In a blinded, split-face, 14-day study, 30 patients were divided into groups of 10. One group received 1.0 mL BEL in the perioral lines on 1 side and 1.0 mL of BEL-LE on the other side. A second group received 1.0 mL of BEL on 1 side and 1.0 mL of BEL-L on the other side. The third group received 1.0 mL of BEL-L on 1 side and 1.0 mL of BEL-LE on the other side. Over 3 visits, the treating investigator, the patients, and a blinded investigator rated the bruising. RESULTS: Bruising occurred in each treatment group by day 1 but resolved for half of the patients by day 7 and for all patients by day 14. Split-face comparison did not reveal a significant difference in pain and bruising scores among the 3 preparations. CONCLUSIONS: No significant difference was found in bruising or pain in patients treated with BEL, BEL-L, and BEL-LE. Studies with a considerably larger sample size are warranted to determine statistically significant and clinically meaningful differences between and among the various formulations.

Peripheral administration of a humanized anti-PrP antibody blocks Alzheimer's disease Aß synaptotoxicity.

Alzheimer's disease (AD) is associated with pathological assembly states of amyloid-ß protein (Aß). Aß-related synaptotoxicity can be blocked by anti-prion protein (PrP) antibodies, potentially allowing therapeutic targeting of this aspect of AD neuropathogenesis. Here, we show that intravascular administration of a high-affinity humanized anti-PrP antibody to rats can prevent the plasticity-disrupting effects induced by exposure to soluble AD brain extract. These results provide an in vivo proof of principle for such a therapeutic strategy.

A 12-month, prospective, evaluator-blinded study of small gel particle hyaluronic acid filler in the correction of temporal fossa volume loss.

OBJECTIVE: The primary objective of this study is to examine the use and persistency of small gel particle hyaluronic acid (SGP-HA) filler (Restylane®; Medicis Aesthetics Inc, Scottsdale, AZ) in the treatment of temporal fossa volumization over a 12-month follow-up, and determine local adverse events (AEs). STUDY DESIGN: This is a US Food and Drug Administration-approved, blinded, prospective, single-center, open-label trial enrolling 20 subjects undergoing subcutaneous injection of SGP-HA for rejuvenation of the temples. Primary outcomes were measured using a standardized grading system—the Hollowness Severity Rating Scale (HSRS)—at each visit by the treating investigator, a blinded physician assessment of randomized photos using the HSRS, and patient questionnaires over a 12-month period. AEs were monitored by the investigator and via patient diaries. RESULTS: At weeks 4, 12, and 24, and month 12, all graders (ie, investigator, blinded physician assessor, and patients) reported improvement overall in hollowness. At baseline, temporal fossa hollowness was measured as moderate to severe. At week 4 to month 12, temporal fossa was graded at none or only mild hollowness. No touch-ups were necessary at week 4 on all subjects. All AEs were mild or moderate and resolved within 2 weeks. CONCLUSION: Our study demonstrates clinically significant efficacy and safety in the use of Restylane for temple augmentation and, thus, facial rejuventation.

A guide to temporal fossa augmentation with small gel particle hyaluronic acid dermal filler.

Loss of volume in the temple can result in a gaunt, wasted appearance. Dermal filler augmentation of the temples can counteract volume loss and achieve a more balanced and youthful appearance. Although the temporal fossa is a critical area for volume restoration of the aging face, published information is limited. The authors retrospectively describe the treatment of 20 female patients who sought facial rejuvenation and received small gel particle hyaluronic acid (SPG-HA) injections for temporal fossa augmentation. The authors discuss a rationale for their choice of dermal filler and provide a detailed, illustrated injection technique guide for restoring volume in the temporal fossa region with SPG-HA. There is a need for prospective, controlled studies investigating safety, efficacy and persistency of hyaluronic acid fillers in this area of the face.

A novel pathogenic pathway of immune activation detectable before clinical onset in Huntington's disease.

Huntington's disease (HD) is an inherited neurodegenerative disorder characterized by both neurological and systemic abnormalities. We examined the peripheral immune system and found widespread evidence of innate immune activation detectable in plasma throughout the course of HD. Interleukin 6 levels were increased in HD gene carriers with a mean of 16 years before the predicted onset of clinical symptoms. To our knowledge, this is the earliest plasma abnormality identified in HD. Monocytes from HD subjects expressed mutant huntingtin and were pathologically hyperactive in response to stimulation, suggesting that the mutant protein triggers a cell-autonomous immune activation. A similar pattern was seen in macrophages and microglia from HD mouse models, and the cerebrospinal fluid and striatum of HD patients exhibited abnormal immune activation, suggesting that immune dysfunction plays a role in brain pathology. Collectively, our data suggest parallel central nervous system and peripheral pathogenic pathways of immune activation in HD.

Intravascular detection of inflamed atherosclerotic plaques using a fluorescent photosensitizer targeted to the scavenger receptor.

Inflammation plays an important role in the pathophysiology of atherosclerotic disease. We have previously shown that the targeted photosensitizer chlorin (e(6)) conjugated with maleylated albumin (MA-ce6) is taken up by macrophages via the scavenger receptor with high selectivity. In a rabbit model of inflamed plaque in New Zealand white rabbits via balloon injury of the aorto-iliac arteries and high cholesterol diet we showed that the targeted conjugate showed specificity towards plaques compared to free ce6. We now show that an intravascular fiber-based spectrofluorimeter advanced along the -iliac vessel through blood detects 24-fold higher fluorescence in atherosclerotic vessels compared to control rabbits (p < 0.001 ANOVA). Within the same animals, signal derived from the injured iliac artery was 16-fold higher than the contralateral uninjured iliac (p < 0.001). Arteries were removed and selective accumulation of MA-ce6 in plaques was confirmed using: (1) surface spectrofluorimetry, (2) fluorescence extraction of ce6 from aortic segments, and (3) confocal microscopy. Immunohistochemical analysis of the specimens showed a significant correlation between MA-ce6 uptake and RAM-11 macrophage staining (R = 0.83, p < 0.001) and an inverse correlation between MA-ce6 uptake and smooth muscle cell staining (R = -0.74, p < 0.001). MA-ce6 may function as a molecular imaging agent to detect and/or photodynamically treat inflamed plaques.

Beta-PrP form of human prion protein stimulates production of monoclonal antibodies to epitope 91-110 that recognise native PrPSc.

Prion diseases are associated with accumulation of strain-dependent biochemically distinct, disease-related isoforms (PrP(Sc)) of host-encoded prion protein (PrP(C)). PrP(Sc) is characterised by increased beta-sheet content, detergent insolubility and protease resistance. Recombinant alpha-PrP adopts a PrP(C)-like conformation, while beta-PrP conformationally resembles PrP(Sc), to these we raised 81 monoclonal antibodies in Prnp(0/0) mice. The N-terminal residues 91-110 are highly immunogenic in beta-PrP-immunised mice and of (17/41) anti-beta-PrP antibodies that could be epitope-mapped, approximately 70%, recognised this segment. In contrast, only 3/40 anti-alpha-PrP antibodies could be mapped and none interacted with this region, instead recognising residues 131-150, 141-160 and 171-190. Native PrP(C) was recognised by both antibody groups, but only anti-beta-PrP antibodies directed to 91-110 residues recognised native PrP(Sc) with high affinity, where in addition, species heterogeneity was also evident. Within the six anti-beta-PrP antibodies studied, they all recognised PK-treated native human and mouse PrP(Sc), four failed to recognise PK-treated native bovine PrP(Sc), one of which also did not recognise native PK-treated ovine PrP(Sc), showing the epitope becomes exposed on unfolding and disaggregation. These results demonstrate strain-dependent variations in chain conformation and packing within the 91-110 region of PrP(Sc).

Elongated oligomers assemble into mammalian PrP amyloid fibrils.

In prion diseases, the mammalian prion protein PrP is converted from a monomeric, mainly alpha-helical state into beta-rich amyloid fibrils. To examine the structure of the misfolded state, amyloid fibrils were grown from a beta form of recombinant mouse PrP (residues 91-231). The beta-PrP precursors assembled slowly into amyloid fibrils with an overall helical twist. The fibrils exhibit immunological reactivity similar to that of ex vivo PrP Sc. Using electron microscopy and image processing, we obtained three-dimensional density maps of two forms of PrP fibrils with slightly different twists. They reveal two intertwined protofilaments with a subunit repeat of approximately 60 A. The repeating unit along each protofilament can be accounted for by elongated oligomers of PrP, suggesting a hierarchical assembly mechanism for the fibrils. The structure reveals flexible crossbridges between the two protofilaments, and subunit contacts along the protofilaments that are likely to reflect specific features of the PrP sequence, in addition to the generic, cross-beta amyloid fold.

PrP glycoforms are associated in a strain-specific ratio in native PrPSc.

Prion diseases involve conversion of host-encoded cellular prion protein (PrPC) to a disease-related isoform (PrPSc). Using recombinant human beta-PrP, a panel of monoclonal antibodies was produced that efficiently immunoprecipitated native PrPSc and recognized epitopes between residues 93-105, indicating for the first time that this region is exposed in both human vCJD and mouse RML prions. In contrast, monoclonal antibodies raised to human alpha-PrP were more efficient in immunoprecipitating PrPC than PrPSc, and some of them could also distinguish between different PrP glycoforms. Using these monoclonal antibodies, the physical association of PrP glycoforms was studied in normal brain and in the brains of humans and mice with prion disease. It was shown that while PrPC glycoforms can be selectively immunoprecipitated, the differentially glycosylated molecules of native PrPSc are closely associated and always immunoprecipitate together. Furthermore, the ratio of glycoforms comprising immunoprecipitated native PrPSc from diverse prion strains was similar to those observed on denaturing Western blots. These studies are consistent with the view that the proportion of each glycoform incorporated into PrPSc is probably controlled in a strain-specific manner and that each PrPSc particle contains a mixture of glycoforms.

Protein conformation significantly influences immune responses to prion protein.

In prion diseases, such as variant Creutzfeldt-Jakob disease normal cellular prion protein (PrPC), a largely alpha-helical structure is converted to an abnormal conformational isoform (PrPSc) that shows an increase in beta-sheet content. Similarly, the recombinant form of PrPC (ralpha-PrP) can be converted to a conformation dominated by beta-sheet (rbeta-PrP) by reduction and mild acidification in vitro, a process that may mimic in vivo conversion following PrPC internalization during recycling. Despite PrPSc accumulation and prion propagation in the lymphoreticular system before detectable neuroinvasion, no Ab response to PrP has been detected, probably due to immune tolerance. To investigate how the immune system may respond to alpha- and beta-PrP, we immunized Prnp(0/0) mice that are not tolerant of PrP with ralpha-PrP and rbeta-PrP. In this study, we show that although T cells stimulated by these differently folded conformers PrP recognize similar immunodominant epitopes (residues 111-130 and 191-210) the cytokine profile in response to ralpha- and rbeta-PrP was different. Challenge with ralpha-PrP elicited a strong response of IL-5 and IL-10, whereas rbeta-PrP led to an early increased production of IFN-gamma. In addition, immunization with ralpha-PrP led to production of predominantly IgG1 isotype Ab in the sera, whereas after immunization with rbeta-PrP, IgG2b was significantly produced. Thus, both humoral and cellular responses to these differently folded isoforms of the same protein are different, indicating a possible involvement of Th1 and Th2 pathway activation. These differences may be exploitable diagnostically and therapeutically for prion diseases, such as variant Creutzfeldt-Jakob disease.