A second space age spanning omics, platforms and medicine across orbits.

The recent acceleration of commercial, private and multi-national spaceflight has created an unprecedented level of activity in low Earth orbit, concomitant with the largest-ever number of crewed missions entering space and preparations for exploration-class (lasting longer than one year) missions. Such rapid advancement into space from many new companies, countries and space-related entities has enabled a 'second space age'. This era is also poised to leverage, for the first time, modern tools and methods of molecular biology and precision medicine, thus enabling precision aerospace medicine for the crews. The applications of these biomedical technologies and algorithms are diverse, and encompass multi-omic, single-cell and spatial biology tools to investigate human and microbial responses to spaceflight. Additionally, they extend to the development of new imaging techniques, real-time cognitive assessments, physiological monitoring and personalized risk profiles tailored for astronauts. Furthermore, these technologies enable advancements in pharmacogenomics, as well as the identification of novel spaceflight biomarkers and the development of corresponding countermeasures. In this Perspective, we highlight some of the recent biomedical research from the National Aeronautics and Space Administration, Japan Aerospace Exploration Agency, European Space Agency and other space agencies, and detail the entrance of the commercial spaceflight sector (including SpaceX, Blue Origin, Axiom and Sierra Space) into aerospace medicine and space biology, the first aerospace medicine biobank, and various upcoming missions that will utilize these tools to ensure a permanent human presence beyond low Earth orbit, venturing out to other planets and moons.

Injectable slurry for selective destruction of neck adipose tissue in New Zealand obese mouse model.

PURPOSE: Increased neck circumference is a major risk factor for obstructive sleep apnea (OSA). New data suggest that increased adipose tissue in the neck may be a contributory cause of OSA. The aim of this study was to investigate safety and efficacy of a recently developed injectable ice slurry in selective reduction of neck adipose tissue in a mouse model. METHODS: We used the New Zealand obese mice that have increased volume of anterior neck fat, and are commonly used in OSA studies. MRI imaging was used to measure changes in fat tissue volume. RESULTS: Thirty animals were used in this study. Volumetric measurements in MRI images showed thatchanges in anterior neck adipose tissue volume from baseline in treated mice was significantly different in comparison with the control group (-1.09/kg ± 0.33/kg vs 0.68/kg ± 0.37/kg; p < 0.01 by two-tailed Student's t test). Histological analysis of samples from the treated area of the neck did not show scarring or damage to the surrounding tissues. CONCLUSIONS: Injection of ice slurry safely, effectively, and selectively reduces upper airway fat in New Zealand obese mice without scarring or damage to surrounding tissue. Our results suggest that slurry injection may be a novel and minimally invasive method of removing neck adipose tissue. This intervention should be further investigated to determine its suitability for treatment of OSA.

Single blind, randomized, controlled trial of a lightening product with and without iontophoresis versus tretinoin and vehicle for hyperpigmentation.

BACKGROUND: Hyperpigmentation is a common concern and has many causes including lentigines and melasma. Currently available topical products for hyperpigmentation are limited by their potential for irritation, lack of demonstrated efficacy or regulatory concerns. OBJECTIVE: To compare the efficacy of a new skin lightening product with and without iontophoresis to a known effective product (tretinoin) and placebo on hyperpigmentation caused by lentigines and/or melasma. Secondary objectives included an assessment of the product's effects on the appearance of rhytides and roughness. METHODS AND MATERIALS: Eighty subjects were randomized into one of four treatment groups: proprietary lightening product, proprietary lightening product with iontophoresis, tretinoin 0.05% cream, or vehicle control. Seventy-four subjects completed all study visits. Blinded assessments of subjects were performed at each visit under ambient and Wood's light. RESULTS: The proprietary skin lightening product improved facial hyperpigmentation versus placebo under ambient light (P= 0.05) and Wood's lamp (P= 0.01) examination. Tretinoin also improved facial hyperpigmentation versus placebo under Wood's lamp (P= 0.01). The proprietary product was better tolerated than tretinoin, with fewer subject reported side effects. CONCLUSION: The investigational product was effective and may be better tolerated than tretinoin cream.

A human lung alveolus-on-a-chip model of acute radiation-induced lung injury.

Acute exposure to high-dose gamma radiation due to radiological disasters or cancer radiotherapy can result in radiation-induced lung injury (RILI), characterized by acute pneumonitis and subsequent lung fibrosis. A microfluidic organ-on-a-chip lined by human lung alveolar epithelium interfaced with pulmonary endothelium (Lung Alveolus Chip) is used to model acute RILI in vitro. Both lung epithelium and endothelium exhibit DNA damage, cellular hypertrophy, upregulation of inflammatory cytokines, and loss of barrier function within 6 h of radiation exposure, although greater damage is observed in the endothelium. The radiation dose sensitivity observed on-chip is more like the human lung than animal preclinical models. The Alveolus Chip is also used to evaluate the potential ability of two drugs - lovastatin and prednisolone - to suppress the effects of acute RILI. These data demonstrate that the Lung Alveolus Chip provides a human relevant alternative for studying the molecular basis of acute RILI and may be useful for evaluation of new radiation countermeasure therapeutics.

Assessing the safety of new germicidal far-UVC technologies.

The COVID-19 pandemic underscored the crucial importance of enhanced indoor air quality control measures to mitigate the spread of respiratory pathogens. Far-UVC is a type of germicidal ultraviolet technology, with wavelengths between 200 and 235 nm, that has emerged as a highly promising approach for indoor air disinfection. Due to its enhanced safety compared to conventional 254 nm upper-room germicidal systems, far-UVC allows for whole-room direct exposure of occupied spaces, potentially offering greater efficacy, since the total room air is constantly treated. While current evidence supports using far-UVC systems within existing guidelines, understanding the upper safety limit is critical to maximizing its effectiveness, particularly for the acute phase of a pandemic or epidemic when greater protection may be needed. This review article summarizes the substantial present knowledge on far-UVC safety regarding skin and eye exposure and highlights research priorities to discern the maximum exposure levels that avoid adverse effects. We advocate for comprehensive safety studies that explore potential mechanisms of harm, generate action spectra for crucial biological effects and conduct high-dose, long-term exposure trials. Such rigorous scientific investigation will be key to determining safe and effective levels for far-UVC deployment in indoor environments, contributing significantly to future pandemic preparedness and response.

Injection Cryolipolysis: First-in-human Study.

BACKGROUND: Injection cryolipolysis using an ice slurry has been hypothesized to be a novel method of reducing fat. The present first-in-human pilot study aims to investigate the feasibility, safety, and tolerability of ice slurry injection into human subcutaneous fat. METHODS: Preabdominoplasty subjects were recruited. Baseline measurements and serial follow-up visits following a single ice slurry injection procedure into tissue to be excised during abdominoplasty were performed. Melted ice slurry injection was used as control. Feasibility using standard injection techniques was assessed. Thermal imaging was used to determine cooling efficacy. Safety was assessed by adverse event monitoring. Tolerability was assessed by subject-reported pain score. Histology and ultrasound were monitored for structural changes associated with cryolipolysis. RESULTS: A single injection of ice slurry was feasible and sufficient to cool adipose below the target temperature (10C). There were no serious adverse events. The most common adverse events were bruising and erythema. The mean pain score for ice slurry-injected sites was 1.9/10 and 1.3/10 in control injection sites. Evidence of cryolipolysis was observed on ultrasound and tissue histology in ice slurry-injected sites. CONCLUSIONS: Ice slurry injections are feasible, with an observed safety and tolerability profile comparable to topical cryolipolysis. The ice slurry can cool tissue to induce cryolipolysis, as observed by thermal imaging, ultrasound, and tissue histology, and is selective for ice-injected sites. No significant changes were observed in control sites. The ice slurry may be a promising candidate to enable more precise, effective, and customizable aesthetic fat reduction that warrants further investigation.

Subcutaneous Fat Reduction with Injected Ice Slurry.

BACKGROUND: Cryolipolysis is a noninvasive method for removal of subcutaneous fat for body contouring. Conventional cryolipolysis with topical cooling requires extracting heat from subcutaneous fat by conduction across the skin, thus limiting the amount and the location of the fat removed. The authors hypothesized that local injection of a physiological ice slurry directly into target adipose tissue would lead to more efficient and effective cryolipolysis. METHODS: Injectable slurries containing 20 percent and 40 percent ice content were made using common parenteral agents (normal saline and glycerol), then locally injected into the subcutaneous fat of swine. Ultrasound imaging, photography, histological, and gross tissue responses were monitored before and periodically up to 8 weeks after injection. RESULTS: Fat loss occurred gradually over several weeks following a single ice slurry injection. There was an obvious and significant 55 ± 6 percent reduction in adipose tissue thickness compared with control sites injected with the same volume of melted slurry (p < 0.001, t test). The amount of fat loss correlated with the total volume of ice injected. There was no scarring or damage to surrounding tissue. CONCLUSION: Physiological ice slurry injection is a promising new strategy for selective and nonsurgical fat removal.

Creation of a Bioengineered Skin Flap Scaffold with a Perfusable Vascular Pedicle.

Full-thickness skin loss is a challenging problem due to limited reconstructive options, demanding 75 million surgical procedures annually in the United States. Autologous skin grafting is the gold standard treatment, but results in donor-site morbidity and poor aesthetics. Numerous skin substitutes are available on the market to date, however, none truly functions as full-thickness skin due to lack of a vascular network. The creation of an autologous full-thickness skin analogue with a vascular pedicle would result in a paradigm shift in the management of wounds and in reconstruction of full-thickness skin defects. To create a clinically relevant foundation, we generated an acellular skin flap scaffold (SFS) with a perfusable vascular pedicle of clinically relevant size by perfusion decellularization of porcine fasciocutaneous flaps. We then analyzed the yielded SFS for mechanical properties, biocompatibility, and regenerative potential in vitro and in vivo. Furthermore, we assessed the immunological response using an in vivo model. Finally, we recellularized the vascular compartment of an SFS and reconnected it to a recipient's blood supply to test for perfusability. Perfusion decellularization removed all cellular components with preservation of native extracellular matrix composition and architecture. Biaxial testing revealed preserved mechanical properties. Immunologic response and biocompatibility assessed via implantation and compared with native xenogenic skin and commercially available dermal substitutes revealed rapid neovascularization and complete tissue integration. Composition of infiltrating immune cells showed no evidence of allorejection and resembled the inflammatory phase of wound healing. Implantation into full-thickness skin defects demonstrated good tissue integration and skin regeneration without cicatrization. We have developed a protocol for the generation of an SFS of clinically relevant size, containing a vascular pedicle, which can be utilized for perfusion decellularization and, ultimately, anastomosis to the recipient vascular system after precellularization. The observed favorable immunological response and good tissue integration indicate the substantial regenerative potential of this platform.

Using the Physician Global Assessment in a clinical setting to measure and track patient outcomes.

IMPORTANCE: In dermatology, the development of objective, standardized quality measures that can be used in a clinical setting is important to be able to respond to the needs of payers and credentialing and licensure bodies and to demonstrate dermatologic value. OBJECTIVE: To examine the feasibility of using Physician Global Assessment (PGA) scores to collect and track patient acne and psoriasis outcomes over time. DESIGN, SETTING, AND PARTICIPANTS: The PGA severity scores were included on physicians' billing sheets for patients with acne and psoriasis seen at a tertiary care center outpatient dermatology clinic from June 2011 through October 2012. A subset of patients from 5 clinics completed Patient Global Assessments (PtGAs) between November 2011 and May 2012. Thirty dermatology clinicians saw a total of 2770 patients with acne and 1516 patients with psoriasis in clinic, recording PGA scores for each patient. The PtGA scores were collected from 52 and 103 patients with acne and psoriasis, respectively, within the larger sample. MAIN OUTCOMES AND MEASURES: Longitudinal PGA severity scores were collected for acne and psoriasis. The PGA severity scores were analyzed over time, with the hypothesis that patient scores for both acne and psoriasis would improve between the initial and follow-up visits. The PtGA scores from a subset of clinics and dates were compared with PGA scores to assess within-clinic reliability, with the hypothesis that there would be good agreement between clinician and patient assessments. RESULTS: New patient PGA outcomes showed considerable improvement over time. At 3-month follow-up, 14.6% of the acne cohort was graded as effectively clear, compared with 2.1% at baseline (P < .001). Similarly, at 3-month follow-up, 22.3% of the psoriasis cohort was graded as effectively clear, compared with 3.1% at baseline (P < .001). Additionally, interobserver agreement between PGA and PtGA scores was good (acne, κ = 0.68; psoriasis, κ = 0.70). CONCLUSIONS AND RELEVANCE: The PGA can be readily incorporated into practice to track patient acne and psoriasis outcomes over time, representing an opportunity for dermatologists to evaluate performance and validate practice guidelines.

Race, rather than skin pigmentation, predicts facial hair growth in women.

BACKGROUND: The Ferriman-Gallwey hirsutism score is the currently accepted standard for assessing excess hair growth that may indicate hyperandrogenicity. The score was originally based on 60 Caucasian women, and recent studies suggest that it may need modification to be used in other populations. OBJECTIVES: To investigate ethnic, racial, and pigmentary variations in hair growth of the upper lip in diverse multinational populations. RESULTS: Variations in hair growth of the upper lip were significantly related to self-reported ethnicity and race. In a logistic regression with racial groups and skin lightness, all racial groupings (African American, Hispanic, Asian Indian, and East Asian) were predictive of hair growth (all p<0.0001), but skin lightness was not (all p>0.05). CONCLUSION: The observed differences in constitutive hair growth illustrate the need to develop an ethnically stratified visual scoring method to more accurately characterize the severity of excess hair growth.