[研究報告] 男性間性交渉者のHIV抗体検査の受検行動に影響する要因と関連性

要旨目的：男性間性交渉者(以下MSM)のHIV抗体検査の受検行動に影響する要因と関連性を明らかにする。方法：多様なセクシャリティのスタッフが営むスナックと性と人権に関するNPO法人へ20歳以上のMSMの紹介を依頼した。５名にHIV感染症/エイズのとらえ方、HIV抗体検査を受ける動機と受けなかった理由について半構造化面接を実施し、質的記述的に分析した。結果：対象者の平均年齢は33.8歳で３名はHIV陽性であった。「HIV感染症/エイズに対する認識」では【感染の恐怖を凌ぐ性欲】【生涯逃れたいHIV感染症/エイズ】【感染する覚悟があるHIV感染症/エイズ】が抽出された。「受検行動に影響する促進要因」では【感染に対する危機意識】【HIV陰性証明の獲得】【ゲイ仲間からの勧奨】、一方「受検行動に影響する阻害要因」では【感染しないという謎の安心感】【HIV陽性判明への恐怖心】【HIV陽性判明による自由にSEXができない不利益】【早期のHIV陽性判明による経済的不利益】【治らないものはあえて受けない】【HIV抗体検査への無関心】【ゲイ告知の困難さ】【検査時のプライバシーへの無配慮】が抽出された。カテゴリの関連性から「リスク自覚時受検行動」「受検離脱行動」「受検回避行動」「受検拒否行動」の４つの受検行動が導き出された。考察：MSMにとってHIV陽性判明は自由な性交渉権利を失う【HIV陽性判明による自由にSEXができない不利益】、身体障害者非該当となった早期HIV陽性者は高額な治療費を強いられてまでは治療を望まない【早期HIV陽性判明は経済的不利益】ととらえていた。Objective: The study was conducted to reveal the factors and related matters affecting the behavior of men who have sex with men (MSM) for HIV antibody tests.Methods: Five people over 20 years of age were introduced by LGBT staff workers of a local bar and a person in charge of an NPO related to sex and human rights. Semi-structured interviews were conducted with those five subjects in regard to their understanding about HIV infection/AIDS, their motivation for taking the HIV antibody test, and/or their reasons for not taking the tests. Then the results were qualitatively and descriptively analyzed.Results: The average age of the subjects was 33.8 years old and three of them were HIV positive. In terms of “awareness of HIV infection/AIDS,” the categories of “Libido that surpasses the fear of infection,” “desire to avoid HIV infection/AIDS for life time,” and “readiness for HIV infection/AIDS” were extracted. Regarding “the facilitating factors affecting their behavior for the tests,” the categories of “awareness that may become infected,” “hope HIV results are negative,” and “recommendation by gay friends” were extracted. When it comes to “the inhibiting factors for the tests,” the categories of “false belief that I don’t get infected,” “fear of HIV results being positive,” “disadvantages of being unable to have sex freely if test positive for HIV,” “economic disadvantage in early stages of HIV positive diagnosis,” “negative feeling towards the tests for an uncurable disease,” “indifference for HIV testing.” “difficulties in coming out as gay,” “lack of considerations for privacy during test” were extracted. In addition, the following four related matters in behaviors toward the test were derived: “the behavior with self-awareness for the risk of in taking test,” “withdrawal behavior after taking the test,” “avoiding the test,” and “rejecting the test.”Discussion: The results shows that MSM are aware that their right to have sexual intercourse freely is lost after receiving an HIV positive result as shown by the category of “disadvantages of being unable to have sex freely if test positive for HIV.” Also, MSM reluctant to receive medical treatment for HIV infection if fees for required treatment are expensive as shown by the category of “economic disadvantage in early stages of HIV positive diagnosis.

Chronic irradiation with low-dose-rate ¹³⁷Cs-γ rays inhibits NGF-induced neurite extension of PC12 cells via Ca²⁺/calmodulin-dependent kinase II activation

Chronic irradiation with low-dose-rate ¹³⁷Cs-γ rays inhibits the differentiation of human neural progenitor cells and influences the expression of proteins associated with several cellular functions. We aimed to determine whether such chronic irradiation influences the expression of proteins associated with PC12 cells. Chronic irradiation at 0.027 mGy/min resulted in inhibition of NGF-induced neurite extension. Furthermore, irradiation enhanced the nerve growth factor (NGF)-induced increase in the phosphorylation of extracellular signal–regulated kinase (ERK), but did not affect the phosphorylation of NGF receptors, suggesting that irradiation influences pathways unassociated with the activation of ERK. We then examined whether irradiation influenced the Akt−Rac1 pathway, which is unaffected by ERK activation. Chronic irradiation also enhanced the NGF-induced increase in Akt phosphorylation, but markedly inhibited the NGF-induced increase in Rac1 activity that is associated with neurite extension. These results suggest that the inhibitory effect of irradiation on neurite extension influences pathways unassociated with Akt activation. As Ca²⁺ /calmodulin-dependent kinase II (CaMKII) is known to inhibit the NGF-induced neurite extension in PC12 cells, independent of ERK and Akt activation, we next examined the effects of irradiation on CaMKII activation. Chronic irradiation induced CaMKII activation, while application of KN-62 (a specific inhibitor of CaMKII), attenuated increases in CaMKII activation and recovered neurite extension and NGF-induced increases in Rac1 activity that was inhibited by irradiation. Our results suggest that chronic irradiation with low-dose-rate γ-rays inhibits Rac1 activity via CaMKII activation, thereby inhibiting NGF-induced neurite extension

逆転写酵素・DNAポリメラーゼを用いたRT-PCRによる増幅反応で確認されたペッパーマイルドモットルウイルス（PMMoV）感染ピーマンの果実種子におけるウイルスの効果的な不活性化方法

A method for efficient inactivation Papper mild mottle virus (PMMoV) in harvested seeds of green pepper was examined based on the infectivity on the leaves of Nicotina glutinosa L.(a local host) and a reverse transcription and polymerase chain reaction (RT-PCR)-based amplification of the viral RNA. The seed homogenates from PMMoV-infected plants produced a large number of necrotic local lesion in N.glutinosa, but soaking the seeds in 10% (w/v) tri-sodium phosphate (Na3PO4) for 20 min or dry sterilization (70C,3h) effectivity eliminated the abundance of PMMoV. However, no necrotic lesion on N.glutinosa or the RT-PCR-basaed amplification was observed with seeds that has been disinfected by Na3PO4 in combination with dry sterilization

Late Established Mutans Streptococci in Children over 3 Years Old

Acquisition of mutans streptococci has been reported to most commonly occur at approximately 26 months of age. In the present study, we detected Streptococcus mutans and S. sobrinus using polymerase chain reaction (PCR) assays in children, then re-examined the subjects to determine the time of acquisition of these bacteria over a 1-year period. The subjects were 57 children ranging in age from 3 to 5 years old, each with primary dentition. Plaque samples were collected from all erupted tooth sites using a sterile toothbrush. PCR assays were performed to detect the targeted mutans streptococci at the beginning of the study (baseline) and after 1 year. At the baseline examination, the prevalence of S. mutans and S. sobrinus was 61.4% and 54.4%, respectively, in all subjects, of whom 14 (24.6%) were positive for S. mutans alone, 10 (17.5%) for S. sobrinus alone, and 21 (36.8%) for both S. mutans and S. sobrinus, with 12 (21.1%) negative for both. After 1 year, 4 of 22 (18.2%) subjects newly had acquired S. mutans and 15 of 26 (57.7%) had aquired S. sobrinus, while 5 (8.8%) remained negative for both bacteria. The age of the first positive S. mutans finding ranged from 49 to 71 months, while that for S. sobrinus ranged from 49 to 81 months old. Our results suggest that S. sobrinus becomes established later than S. mutans in the oral cavities of children over the age of 3 years old