Dermoscopic features distinctive for extraocular sebaceous carcinoma

We examined dermoscopic features of three cases of extraocular sebaceous carcinoma and reviewed the literatures. The yellowish structures, polymorphous vessels and ulceration were common findings in our cases and all cases of the previous reports. The appearance of whitish‐pink areas has not been described previously. Our results suggested that the combination of four dermoscopic features, whitish‐pink areas, yellowish structures, polymorphous vessels and ulceration might be distinctive in extraocular sebaceous carcinoma.     

Involvement of monoamine oxidase-B in the acute neurotoxicity of MPTP in embryonic and newborn mice

1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) induces damage to the nigrostriatal system and subventricular zone (SVZ) of mice. While there have been many researches on the neurotoxicity of MPTP in adult mice, there have been few reports concerning that in embryonic and newborn mice. Very recently, we revealed that such neurotoxicity of MPTP and 1-methyl-4-phenylpyridinium (MPP⁺), a metabolite of MPTP, is observed not only in adult mice but also in embryonic and newborn mice; however, the mechanism of acute toxicity is not well elucidated. In the present study, we attempted to reveal the involvement of monoamine oxidase B (MAO-B) in the metabolism of MPTP to MPP⁺ and dopamine transporter (DAT) in the neuronal cellular uptake of MPP⁺ during the acute toxicity of MPTP in both embryonic and newborn mice. Immunohistochemistry and double-labeling immunofluorescent staining demonstrated an increase of MAO-B-positive glial cells in the brain only in MPTP-treated mice, indicating the involvement of MAO-B in the metabolism of MPTP to MPP⁺ during the acute neurotoxicity of MPTP in both embryonic and newborn mice. The expression of DAT was not observed in the nigrostriatal zone of embryonic mice and in the zone and SVZ of newborn mice. The mechanism of how MPP⁺ is taken up into those neuronal cells remains unknown. In conclusion, MAO-B is involved in the acute neurotoxicity of MPTP in embryonic and newborn mice.     

Modified oxygen mask to induce target levels of hyperoxia and hypercarbia during radiotherapy: A more effective alternative to carbogen

Purpose: Carbogen has long been under investigation as an adjuvant to radiotherapy of tumors. A major factor confounding its evaluation is its inconsistency in raising blood partial pressure of CO₂ (pCO₂). We investigated whether a new partial rebreathing method would provide better control of pCO₂ than carbogen.

Methods and materials: We compared the efficacy of each method in 10 healthy volunteers. Volunteers breathed 1.5, 3 and 5% carbogen in 5-min stages via the usual non-rebreathing circuit. All the volunteers then breathed 100% O₂ through a commercial sequential gas delivery (SGD) circuit modified by attaching a reservoir to its exhalation port. Hypercarbia was induced by step reductions in oxygen flow to the SGD circuit. We monitored minute ventilation and end-tidal pCO₂ (ETpCO₂) as a surrogate for its arterial value.

Results: Inhalation of 1.5 and 3% carbogen did not increase ETpCO₂ from baseline (40 ± 1.5 mmHg); 5% carbogen increased ETpCO₂ to 45 ± 1.6 mmHg (p < 0.001). With the SGD circuit, reducing O₂ flow to 4.3 ± 0.7 l/min increased ETpCO₂ in all subjects from 41 ± 2.0 mmHg (baseline) to 46 ± 2.1 mmHg (p < 0.001). Voluntary hyperventilation reduced ETpCO₂ with 5% carbogen but not with SGD (p = 0.379).

Conclusions: We confirm previous observations that carbogen inhalation does not result in a predictable rise in ETpCO₂ and suggest that a precise and stable target ETpCO₂ can instead be induced by simply controlling O₂ flow into a modified SGD circuit. We hoped that the reliable control of pCO₂ will enable studies that address first, the efficacy of raising ETpCO₂ on specific tumor blood flow, and eventually, its benefit as an adjuvant to radiotherapy.     

iPhone charger-induced chemical burn from overnight contact with sweat: Two cases

Smartphones have become essential devices in modern society. The coverage rate of smartphones in 2017 in Japan was 75% according to the Ministry of Internal Affairs and Communications. The iPhone is one of the most well-known smartphone brands. According to the manufacturer of iPhones (Apple), more than 200 million iPhones had been sold worldwide by 2017. These devices are often charged at night-time, especially while being used in bed. There are only three reports of smartphone charger-induced skin damage. We present two new cases of skin ulcers induced by an iPhone charger. The iPhone’s “lightning cable” has electrodes outside, and we found that this can present a higher risk of causing a skin injury compared with other types of phone chargers. We also investigated the mechanism of the skin ulcers caused by the iPhone charger. The results indicated that these ulcers were chemical burns rather than an electrical injury or heat-induced burn.     

Intraneural blood flow analysis during an intraoperative Phalen's test in carpal tunnel syndrome

Phalen's test has been one of the most significant of clinical signs when making a clinical diagnosis of idiopathic carpal tunnel syndrome (CTS). However, it is unknown whether intraneural blood flow changes during Phalen's test in patients with CTS. In this study, an intraoperative Phalen's test was conducted in patients with CTS to observe the changes in intraneural blood flow using a laser Doppler flow meter. During Phalen's test, intraneural blood flow showed a sharp decrease, which lasted for 1 min. Intraneural blood flow decreased by 56.7%–100% (average, 78.0%) in the median nerve relative to the blood flow before the test. At 1 min after completing the test, intraneural blood flow returned to the baseline value. After carpal tunnel release, there was no marked decrease in intraneural blood flow. This study demonstrated that the blood flow in the median nerve is reduced when Phalen's test is performed in vivo. © 2010 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 28:1022–1025, 2010