HIV Pre-Exposure Prophylaxis and Postexposure Prophylaxis in Japan: Context of Use and Directions for Future Research and Action.

Biomedical HIV prevention strategies are playing an increasingly prominent role in addressing HIV epidemics globally, but little is known about their use in Japan, where persistent HIV disparities and a recently stable, but not declining, national epidemic indicate the need for evolving approaches. We conducted an ethnographic study to determine the context of pre-exposure prophylaxis (PrEP) and postexposure prophylaxis (PEP) use and to identify directions for future research and action in Japan. We used data from observational fieldwork in the Kansai region and Tokyo Metropolitan Area (n = 178 persons observed), qualitative interviews (n = 32), documents and web-based data sources (n = 321), and email correspondences (n = 9) in the period 2013-2016. Drug approvals by Japan's regulatory agencies, insurance coverage for medications, and policies by healthcare institutions and government agencies were the main factors affecting PrEP and PEP legality, use, and awareness. Awareness and the observable presence of PrEP and PEP were very limited, particularly at the community level. PrEP and PEP held appeal for Japanese scientists and activists, and for study participants who represented various other stakeholder groups; however, significant concerns prevented open endorsements. Japanese health officials should prioritize a national discussion, weigh empirical evidence, and strongly consider formal approval of antiretroviral (ARV) medications for use in PrEP and both occupational and nonoccupational PEP. Once approved, social marketing campaigns can be used to advertise widely and increase awareness. Future research would benefit from theoretical grounding in a diffusion of innovations framework. These findings can inform current and future ARV-based prevention strategies at a critical time in the international conversation.

Unexpected radiation laryngeal necrosis after carbon ion therapy using conventional dose fractionation for laryngeal cancer.

Carbon ion therapy is a type of radiotherapy that can deliver high-dose radiation to a tumor while minimizing the dose delivered to organs at risk. Moreover, carbon ions are classified as high linear energy transfer radiation and are expected to be effective for even photon-resistant tumors. A 73-year-old man with glottic squamous cell carcinoma, T3N0M0, refused laryngectomy and received carbon ion therapy of 70 Gy (relative biological effectiveness) in 35 fractions. Three months after the therapy, the patient had an upper airway inflammation, and then laryngeal edema and pain occurred. Five months after the therapy, the airway stenosis was severe and computed tomography showed lack of the left arytenoid cartilage and exacerbation of laryngeal necrosis. Despite the treatment, 5 and a half months after the therapy, the laryngeal edema and necrosis had become even worse and the surrounding mucosa was edematous and pale. Six months after the therapy, pharyngolaryngoesophagectomy and reconstruction with free jejunal autograft were performed. The surgical specimen pathologically showed massive necrosis and no residual tumor. Three years after the carbon ion therapy, he is alive without recurrence. The first reported laryngeal squamous cell carcinoma case treated with carbon ion therapy resulted in an unexpected radiation laryngeal necrosis. Tissue damage caused by carbon ion therapy may be difficult to repair even for radioresistant cartilage; therefore, hollow organs reinforced by cartilage, such as the larynx, may be vulnerable to carbon ion therapy. Caution should be exercised when treating tumors in or adjacent to such organs with carbon ion therapy.

Rheo-SANS studies on shear-thickening/thinning in aqueous rodlike micellar solutions.

Shear-induced thickening/thinning phenomena of aqueous rodlike micellar solutions of cetyltrimethylammonium bromide (CTAB) and sodium p-toluene sulfonate (NapTS) were investigated by means of simultaneous measurements of rheology and small-angle neutron scattering (SANS), the so-called Rheo-SANS. The aqueous CTAB/NapTS solutions were classified into five different categories dependent on their flow behavior and micellar structure. By increasing salt concentration and/or shear rates, the micelles underwent morphological transition from (i) spherical or short rodlike micelles to (ii) long rodlike micelles without entanglements, followed by (iii) those with entanglements. These transitions were recognized as changes in flow behavior from Newtonian to shear-thickening and shear-thinning flow, respectively. In the latter two cases, anisotropic SANS patterns appeared around these critical shear rates. The physical meaning of the anisotropic SANS patterns accompanied by shear-thickening flow behavior is discussed in conjunction with other shear-thickening systems.