Fluorescence behaviour of human arterial tissue

Total fluorescence from arterial tissue is influenced by three factors: the absorption coefficient of tissue at a specific excitation wavelength, the laser excitation power and the fluorescence coefficient which is related to chemical species in tissue. These various influences were demonstrated by the following experimental results in vitro: (1) the effect of increasing power on fluorescence intensity, (2) the total fluorescence intensity in normal aorta and plaque and (3) the effect of a chromophore such as β-carotene on total fluorescence intensity. The fluorescence intensity of normal artery is an incremental function of laser excitation power, and the fluorescence emission from normal artery compared to fluorescence emission from plaque is significantly different at the same excitation power. The total fluorescence of normal artery was measured to be twice as great as that of atheromatous plaque (relative mean ratio of 2.58±0.46 compared to unity,p<0.0002 at 488 nm; relative mean ratio of 2.57±0.51 compared to unity,p<0.0009 at 514 nm). The total fluorescence emission decreases with the increase of β-carotene content in arterial tissue (R=0.97). These emission differences, when intensified by an exogenous chromophore of β-carotene, may provide an improved guidance signal for diagnosis of plaque from normal artery during laser angioplasty procedures.     

社交性应激反应问卷中文版在大学生中应用的信效度初步评价

目的：建立社交性应激反应问卷（RSQ-SSV）中文版，并分析其信、效度。方法：按量表翻译程序将RSQ—SSV翻译成中文，整群分层选取409名大学生进行RSQ—SSV中文版的测量。随机抽取90名学生于初评后一个月进行重测，并与美国样本进行比较。结果：RSQ-SSV中文版整个问卷的Cronbach α系数为0．88，各因子仅系数在0．73～0．81之间；重测信度为0．70；全量表的条目间平均相关系数为0．11，5因子的条目间平均相关系数在0．19～0．29之间，因子间相关系数在0．12～0．76之间；条目对因子负荷系数在0．38—0．86之间，复相关系数在0．14—0．74之间；验证性因子分析的指标：IFI为0．93，CFI为0．93，TLI为0．92，RMSEA为0．06。中国大学生样本的不随意的逃避反应因子得分高于美国大学生样本[（0．97&#177;0．41）vs．（0．91&#177;0．48），P=0．002]，而初级亲近控制应对反应、次级亲近控制应对反应、不随意的亲近反应得分均低于美国大学生样本[（1．75&#177;0．49）vs．（2．12&#177;0．50）、（1．51&#177;0．43）vs．（1．80&#177;0．48）、（1．17&#177;0．44）vs．（1．36&#177;0．56），均P〈0．001]。结论：RSQ-SSV中文版具有良好的信、效度，可以试用于我国大学生社交性应激反应的测评。     

大、中学生对文化维度的知觉

目的:考察大、中学生对文化维度的知觉的情况和发展趋势。方法:用Trandis编制的个人主义-集体主义量表(Individualism-Collectivism Scale)对1760名大、中学生进行测量。结果:大、中学生对文化维度的知觉存在年龄效应;随着年龄增加,对集体主义维度的知觉从42.05%下降到27.40%,而对个人主义维度的知觉从5.01%上升到18.58%;水平维度的知觉从47.06%下降到40.71%;垂直维度的知觉从4.14%上升到6.19%。结论:大、中学生对文化维度的知觉的差异主要表现在个人主义和集体主义的维度,水平维度和垂直维度有轻微的波动。     

Intersecting stigma and HIV testing practices among urban refugee adolescents and youth in Kampala,Uganda: qualitative findings

IntroductionHIV‐related risks may be exacerbated in humanitarian contexts. Uganda hosts 1.3 million refugees, of which 60% are aged under 18. There are knowledge gaps regarding HIV testing facilitators and barriers, including HIV and intersecting stigmas, among urban refugee youth. In response, we explored experiences and perspectives towards HIV testing strategies, including HIV self‐testing, with urban refugee youth in Kampala, Uganda.MethodsWe implemented a qualitative study with refugee cisgender youth aged 16 to 24 living in Kampala''s informal settlements from February‐April 2019. We conducted five focus groups with refugee youth, including two with adolescent boys and young men, two with adolescent girls and young women and one with female sex workers. We also conducted five key informant (KI) interviews with government, non‐government and community refugee agencies and HIV service providers. We conducted thematic analyses to understand HIV testing experiences, perspectives and recommendations.ResultsParticipants (n = 49) included young men (n = 17) and young women (n = 27) originally from the Democratic Republic of Congo [DRC] (n = 29), Rwanda (n = 11), Burundi (n = 3) and Sudan (n = 1), in addition to five KI (gender: n = 3 women, n = 2 men; country of origin: n = 2 Rwanda, n = 2 Uganda, n = 1 DRC). Participant narratives revealed stigma drivers included fear of HIV infection; misinformation that HIV is a “Ugandan disease”; and blame and shame for sexual activity. Stigma facilitators included legal precarity regarding sex work, same‐sex practices and immigration status, alongside healthcare mistreatment and confidentiality concerns. Stigma experiences were attributed to the social devaluation of intersecting identities (sex work, youth, refugees, sexual minorities, people living with HIV, women). Participants expressed high interest in HIV self‐testing. They recommended HIV self‐testing implementation strategies to be peer supported and expressed concerns regarding sexual‐ and gender‐based violence with partner testing.ConclusionsIntersecting stigma rooted in fear, misinformation, blame and shame, legal precarity and healthcare mistreatment constrain current HIV testing strategies with urban refugee youth. Findings align with the Health Stigma and Discrimination Framework that conceptualizes stigma drivers and facilitators that devalue intersecting health conditions and social identities. Findings can inform multi‐level strategies to foster enabling HIV testing environments with urban refugee youth, including tackling intersecting stigma and leveraging refugee youth peer support.     

Epidemiology and control of brucellosis in ruminants from 1986 to 1996 in Malta

The epidemiology and control of Brucella melitensis in Malta was analysed using herd test data made available by the Veterinary Service of Malta. The eradication scheme commenced in 1987 with the introduction of a test and slaughter scheme using the Rose Bengal test. Herds registered with Malta Dairy Products Limited (MDP) showed a herd prevalence of 23% in 1987 which fell to less than 1.5% by 1993. Prevalence rose to 13% in 1995. Herds not delivering milk to the MDP showed an initial herd prevalence of 4% which fell below 1% in 1994, remaining under 2% in 1995. The epidemic in 1995 caused approximately 300 human brucellosis cases. Large herds and herds with small ruminants were most at risk to brucellosis infection. Seasonal fluctuation of prevalence was apparent. Increased enforcement of regulations and motivation of farmers would accelerate eradication of brucellosis in Malta.     

Monitoring cerebral oxygenation during balloon occlusion with multichannel NIRS

We report on oxygenation changes noninvasively recorded by multichannel continuous-wave near infrared spectroscopy (CW-NIRS) during endovascular neuroradiologic interventions requiring temporary balloon occlusion of arteries supplying the cerebral circulation. Digital subtraction angiography (DSA) provides reference data on the site, timing, and effectiveness of the flow stagnation as well as on the amount and direction of collateral circulation. This setting allows us to relate CW-NIRS findings to brain specific perfusion changes. We focused our analysis on the transition from normal perfusion to vessel occlusion, i.e., before hypoxia becomes clinically apparent. The localization of the maximal response correlated either with the core (occlusion of the middle cerebral artery) or with the watershed areas (occlusion of the internal carotid artery) of the respective vascular territories. In one patient with clinically and angiographically confirmed insufficient collateral flow during carotid artery occlusion, the total hemoglobin concentration became significantly asymmetric, with decreased values in the ipsilateral watershed area and contralaterally increased values. Multichannel CW-NIRS monitoring might serve as an objective and early predictive marker of critical perfusion changes during interventions—to prevent hypoxic damage of the brain. It also might provide valuable human reference data on oxygenation changes as they typically occur during acute stroke.