Skin test reactions were evaluated in 242 patients who appeared to develop delayed type drug eruptions from the clinical course. The patch testing was positive in 62 (31.5%) of 197 patients tested and the intradermal testing in 105 (89.7%) of 117 patients. The positive ratios of intradermal testing were higher in maculopapular (MP), erythema multiforme (EM), and erythrodermic (ED) types than in eczematous (Ecz) type drug eruptions, while those of patch testing were comparatively high in ED, Ecz type, and anticonvulsant-induced drug eruptions. It is considered that the combination of patch testing and intradermal testing is useful for determination of causative drugs in delayed type drug eruptions.

Brain microvascular endothelial cells (BMEC), together with astrocytes and pericytes, form the blood−brain barrier (BBB) that strictly restricts drug penetration into the brain. Therefore, in central nervous system drug development, the establishment of an in vitro human BBB model for use in studies estimating the in vivo human BBB permeability of drug candidates has long been awaited. The current study developed and characterized a human immortalized cellbased BBB triculture model, termed the "hiBBB" model. To set up the hiBBB model, human immortalized BMEC (HBMEC/ci18) were cocultured with human immortalized astrocytes (HASTR/ci35) and brain pericytes (HBPC/ci37) in a transwell system. The trans-endothelial electrical resistance of the hiBBB model was 134.4 ± 5.5 (Ω × cm 2 ), and the efflux ratios of rhodamine123 and dantrolene were 1.72 ± 0.11 and 1.72 ± 0.45, respectively, suggesting that the hiBBB model possesses essential cellular junction and efflux transporter functions. In BBB permeability assays, the mean value of the permeability coefficients (P e ) of BBB permeable compounds (propranolol, pyrilamine, memantine, and diphenhydramine) was 960 × 10 −6 cm/s, which was clearly distinguishable from that of BBB nonpermeable compounds (sodium fluorescein and Lucifer yellow, 18 × 10 −6 cm/s). Collectively, this study successfully developed the hiBBB model, which exhibits essential BBB functionality. Taking into consideration the high availability of the immortalized cells used in the hiBBB model, our results are expected to become an initial step toward the establishment of a useful human BBB model to investigate drug penetration into the human brain.

While pericytes wrap around microvascular endothelial cells throughout the human body, their highest coverage rate is found in the brain. Brain pericytes actively contribute to various brain functions, including the development and stabilization of the blood-brain barrier (BBB), tissue regeneration, and brain inflammation. Accordingly, detailed characterization of the functional nature of brain pericytes is important for understanding the mechanistic basis of brain physiology and pathophysiology. Herein, we report on the development of a new human brain pericyte cell line, hereafter referred to as the human brain pericyte/conditionally immortalized clone 37 (HBPC/ci37). Developed via the cell conditionally immortalization method, these cells exhibited excellent proliferative ability at 33 °C. However, when cultured at 37 °C, HBPC/ci37 cells showed a differentiated phenotype that was marked by morphological alterations and increases in several pericyte-enriched marker mRNA levels, such as platelet-derived growth factor receptor β. It was also found that HBPC/ci37 cells possessed the facilitative ability of in vitro BBB formation and differentiation into a neuronal lineage. Furthermore, HBPC/ci37 cells exhibited the typical "reactive" features of brain pericytes in response to pro-inflammatory cytokines. To summarize, our results clearly demonstrate that HBPC/ci37 cells possess the ability to perform several key brain pericyte functions while also showing the capacity for extensive and continuous proliferation. Based on these findings, it can be expected that, as a unique human brain pericyte model, HBPC/ci37 cells have the potential to contribute to significant advances in the understanding of human brain pericyte physiology and pathophysiology.

Background Delayed identification of infiltration and dysfunction of peripheral intravenous (PIV) access can lead to serious consequences during general anesthesia in children. This preliminary study aimed to describe the application of precordial Doppler ultrasound during general anesthesia in children to detect and confirm the correct PIV access and to evaluate the accuracy of this method. Methods This was a single-center, preliminary study that was conducted in children (<18 years) who were scheduled for elective surgeries between October 2019 and March 2020. Rater anesthesiologists judged the change in precordial Doppler sound (S test) before and after injection of 0.5 mL/kg of normal saline (NS) via PIV. Blood flow velocity before and after NS injection was recorded, and multiple cutoff points were set to analyze the accuracy of detecting the infiltration and dysfunction of PIV catheter (V test). Results The total incidence of peripheral infiltration and dysfunction of PIV catheter was 7/512 (1.4%). In the S test, the sensitivity, specificity, positive and negative likelihood ratios, and area under the receiver-operating characteristic curves (AUCs) were 5/7 (71.4%; 95% confidence interval [CI], 29.0%–96.3%), 490/505 (97.0%; 95% CI, 95.1%–98.3%), 24.0, 0.29, and 0.84, respectively. The V test showed that the reasonable threshold of blood flow velocity change was 1.0 m/s, with sensitivity, specificity, positive and negative likelihood ratios, and AUC of 4/7 (57.1%; 95% CI, 18.4%–90.1%), 489/505 (96.8%; 95% CI, 94.9%–98.2%), 18.0 and 0.44, and 0.84, respectively. Conclusions This preliminary study demonstrated that precordial Doppler ultrasound is a feasible, easy-to-use, and noninvasive technique with good accuracy to confirm the correct PIV access during general anesthesia in children. However, its accuracy requires further evaluation.

Sulfhydryl drug-induced skin eruptions were studied clinically and histologically in 23 patients. In this study, tiopronin, D-penicillamine, captopril and gold sodium thiomalate were considered to be sulfhydryl drugs, because they have a thiol group or release sulfhydryl compounds. The clinical features included skin eruptions that were maculopapular, erythema multiforme-like, eczematous, psoriasis-like, seborrheic dermatitis-like, Gibert-like, lichen planus-like, and pemphigus-like. These clinical findings were reminiscent of the wide variety of eruptions seen in cutaneous graft-versus-host reactions (GVHR). Histologically, areas of vacuolation and eosinophilic necrosis with a satellite infiltrate of lymphoid cells were seen in the epidermis, and perivascular infiltrates were noted in the dermis. These findings were similar to the histological picture of cutaneous GVHR. In skin tests with sulfhydryl compounds, 19 out of 20 subjects showed positive reactions, and autoantibodies were found in 8 out of 12 subjects tested. Sulfhydryl drugs seem likely to induce immunologic changes in the host and to produce a distinctive reaction similar to that of cutaneous GVHR.