Orbital period change of Dimorphos due to the DART kinetic impact.

The Double Asteroid Redirection Test (DART) spacecraft successfully performed the first test of a kinetic impactor for asteroid deflection by impacting Dimorphos, the secondary of near-Earth binary asteroid (65803) Didymos, and changing the orbital period of Dimorphos. A change in orbital period of approximately 7 min was expected if the incident momentum from the DART spacecraft was directly transferred to the asteroid target in a perfectly inelastic collision1, but studies of the probable impact conditions and asteroid properties indicated that a considerable momentum enhancement (ß) was possible2,3. In the years before impact, we used lightcurve observations to accurately determine the pre-impact orbit parameters of Dimorphos with respect to Didymos4-6. Here we report the change in the orbital period of Dimorphos as a result of the DART kinetic impact to be -33.0 ± 1.0 (3σ) min. Using new Earth-based lightcurve and radar observations, two independent approaches determined identical values for the change in the orbital period. This large orbit period change suggests that ejecta contributed a substantial amount of momentum to the asteroid beyond what the DART spacecraft carried.

Ejecta from the DART-produced active asteroid Dimorphos.

Some active asteroids have been proposed to be formed as a result of impact events1. Because active asteroids are generally discovered by chance only after their tails have fully formed, the process of how impact ejecta evolve into a tail has, to our knowledge, not been directly observed. The Double Asteroid Redirection Test (DART) mission of NASA2, in addition to having successfully changed the orbital period of Dimorphos3, demonstrated the activation process of an asteroid resulting from an impact under precisely known conditions. Here we report the observations of the DART impact ejecta with the Hubble Space Telescope from impact time T + 15 min to T + 18.5 days at spatial resolutions of around 2.1 km per pixel. Our observations reveal the complex evolution of the ejecta, which are first dominated by the gravitational interaction between the Didymos binary system and the ejected dust and subsequently by solar radiation pressure. The lowest-speed ejecta dispersed through a sustained tail that had a consistent morphology with previously observed asteroid tails thought to be produced by an impact4,5. The evolution of the ejecta after the controlled impact experiment of DART thus provides a framework for understanding the fundamental mechanisms that act on asteroids disrupted by a natural impact1,6.

Treatment of Bullous Pemphigoid With Dupilumab: A Case Series of 30 Patients.

Bullous pemphigoid is often difficult to treat with the limited therapies available. Here, we describe clinical outcomes among 30 adults with bullous pemphigoid patients treated with dupilumab. We performed a multicenter, retrospective case series between March 2020 to August 2022. Patients received a loading dose of dupilumab 600 mg, followed by 300 mg maintenance dose with varying administration frequency tailored to individual patient response. All patients experienced at least some improvement in blister formation and pruritus, with 23 (76.7%) of patients demonstrating either complete clearance of blistering or marked response. Complete clearance of pruritus or marked response was noted in 25 (83.3%) of patients. Eight patients were effectively maintained solely on dupilumab. One (3.3%) patient reported an injection site reaction. Thirty patients represent a small sample, however, to our knowledge, this is the second largest group of BP treated with dupilumab. Furthermore, we provide an understandable framework for clinicians outside of academics to follow and assess treatment responses in their BP patients treated with dupilumab. Dupilumab should be considered as a therapeutic option in patients with bullous pemphigoid given its ability to induce sustained blistering and pruritus response in both typical and refractory cases while maintaining a favorable safety profile. J Drugs Dermatol. 2024;23(6):e144-e148. doi:10.36849/JDD.8258e.

Severe Mpox Infections in People With Uncontrolled Human Immunodeficiency Virus.

In the current mpox outbreak, infections are usually self-limited. We describe 3 patients with uncontrolled HIV and mpox infections lasting months, causing debilitating lesions, complications, and death, despite initiating anti-mpox and antiretroviral therapy. Delayed treatment of mpox with antiviral agents may contribute to poor outcomes in severely immunocompromised patients.

Trichophyton onychomycosis and deep dermatophytosis in a post-heart transplant patient.

Deep dermatophytosis is an uncommon fungal infection of the dermis most often seen in the setting of immunocompromise. We report a case of trichophyton deep dermatophytosis in a patient with a history of orthotopic heart transplantation who presented with superficial white onychomycosis and papules and plaques on the legs.

Treatment practices in the management of scabies in infants younger than two months.

BACKGROUND/OBJECTIVES: Efficacy and safety data of scabies treatments in infants are limited. Although topical permethrin is used in the treatment of scabies in adults, it is not approved for use in infants younger than 2 months of age in many parts of the world. This study aimed to describe treatment practices in the management of scabies in infants younger than 2 months. METHODS: An online survey was developed and distributed to physicians worldwide through the Society of Pediatric Dermatology and the Pediatric Dermatology Research Alliance. Data collected included demographics, medication availability, experience using medications, deterrents to medication use, medication administration preferences, perceived and experienced medication side effects, and preferred treatment agent in this population. RESULTS: In total, 57 physicians from seven countries responded. The majority of respondents were board-certified in pediatric dermatology (48/57, 84.2%) and resided in the United States (44/57, 77.2%). Respondents had experience using permethrin (47/57, 82.5%) and precipitated sulfur (35/57, 61.4%) most frequently. Most (38/57, 66.7%) preferred permethrin as their treatment of choice. Among those who did not use permethrin, potential side effects (8/10, 80%) were most frequently reported as a deterrent from its use. However, only 4.3% (22/47) of those who used permethrin reported side effects, including itching, erythema, and xerosis. CONCLUSIONS: Permethrin is frequently used in the treatment of infants younger than 2 months with scabies. Furthermore, our results demonstrate that permethrin is the preferred treatment agent among sampled dermatologists for infants younger than 2 months. Few side effects were reported, and none were serious.

Ectoparasites: Pediculosis and tungiasis.

Pediculosis is an infestation of lice on the body, head, or pubic region that occurs worldwide. Lice are ectoparasites of the order Phthiraptera that feed on the blood of infested hosts. Their morphotype dictates their clinical features. Body lice may transmit bacterial pathogens that cause trench fever, relapsing fever, and epidemic typhus, which are potentially life-threatening diseases that remain relevant in contemporary times. Recent data from some settings suggest that head lice may harbor pathogens. The epidemiology, clinical manifestations, and management of body, head, and pubic louse infestation are reviewed. New therapies for head lice and screening considerations for pubic lice are discussed. Tungiasis is an ectoparasitic disease caused by skin penetration by the female Tunga penetrans or, less commonly, Tunga trimamillata flea. It is endemic in Latin America, the Caribbean and sub-Saharan Africa and seen in travelers returning from these regions. Risk factors for acquiring tungiasis, associated morbidity, and potential strategies for prevention and treatment are discussed.

Ectoparasites: Scabies.

Scabies is an ectoparasitic dermatosis caused by Sarcoptes scabiei var. hominis and is a public health issue in all countries regardless of socioeconomic status. In high-income countries, delays in diagnosis can lead to institutional outbreaks; in low- and middle-income countries, poor access to health care contributes to disease undertreatment and long-term systemic sequelae. With scabies now recognized as a neglected tropical disease by the World Health Organization, increased awareness and systematic efforts are addressing gaps in diagnosis and treatment that impede scabies control. This review summarizes the available data and provides an update on scabies epidemiology, clinical features, diagnosis, management, and public health considerations.

Subcutaneous granuloma annulare involving the scalp.

Subcutaneous granuloma annulare (SGA) is an uncommon subtype of granuloma annulare. There are few reports of this entity solely affecting the scalp. We report a case of biopsy-proven SGA in a 21-month-old boy with six asymptomatic, rock-hard scalp nodules.

Earth encounters as the origin of fresh surfaces on near-Earth asteroids.

Telescopic measurements of asteroids' colours rarely match laboratory reflectance spectra of meteorites owing to a 'space weathering' process that rapidly reddens asteroid surfaces in less than 10(6) years. 'Unweathered' asteroids (those having spectra matching the most commonly falling ordinary chondrite meteorites), however, are seen among small bodies the orbits of which cross inside Mars and the Earth. Various explanations have been proposed for the origin of these fresh surface colours, ranging from collisions to planetary encounters. Less reddened asteroids seem to cross most deeply into the terrestrial planet region, strengthening the evidence for the planetary-encounter theory, but encounter details within 10(6) years remain to be shown. Here we report that asteroids displaying unweathered spectra (so-called 'Q-types') have experienced orbital intersections closer than the Earth-Moon distance within the past 5 x 10(5) years. These Q-type asteroids are not currently found among asteroids showing no evidence of recent close planetary encounters. Our results substantiate previous work: tidal stress, strong enough to disturb and expose unweathered surface grains, is the most likely dominant short-term asteroid resurfacing process. Although the seismology details are yet to be worked out, the identification of rapid physical processes that can produce both fresh and weathered asteroid surfaces resolves the decades-long puzzle of the difference in colour of asteroids and meteorites.

Imaging More than Skin-Deep: Radiologic and Dermatologic Presentations of Systemic Disorders.

BACKGROUND: Cutaneous manifestations of systemic diseases are diverse and sometimes precede more serious diseases and symptomatology. Similarly, radiologic imaging plays a key role in early diagnosis and determination of the extent of systemic involvement. Simultaneous awareness of skin and imaging manifestations can help the radiologist to narrow down differential diagnosis even if imaging findings are nonspecific. AIMS: To improve diagnostic accuracy and patient care, it is important that clinicians and radiologists be familiar with both cutaneous and radiologic features of various systemic disorders. This article reviews cutaneous manifestations and imaging findings of commonly encountered systemic diseases. CONCLUSIONS: Familiarity with the most disease-specific skin lesions help the radiologist pinpoint a specific diagnosis and consequently, in preventing unnecessary invasive workups and contributing to improved patient care.