Do social support and community engagement act as mechanisms in the association between neighbourhood income inequality and the mental health of mothers in Calgary,Canada? A mediation analysis

PurposeAccording to the social determinants of health framework, income inequality is a potential risk factor for adverse mental health. However, few studies have explored the mechanisms suspected to mediate this relationship. The current study addresses this gap through a mediation analysis to determine if social support and community engagement act as mediators linking neighbourhood income inequality to maternal anxiety and depressive symptoms within a cohort of new mothers living in the City of Calgary, Canada.MethodsData collected at three years postpartum from mothers belonging to the All Our Families (AOF) cohort were used in the current study. Maternal data were collected between 2012 and 2015 and linked to neighbourhood socioeconomic data from the 2006 Canadian Census. Income inequality was measured using Gini coefficients derived from 2006 after-tax census data. Generalized structural equation models were used to quantify the associations between income inequality and mental health symptoms, and to assess the potential direct and indirect mediating effects of maternal social support and community engagement.ResultsIncome inequality was not significantly associated with higher depressive symptoms (β = 0.32, 95%CI = −0.067, 0.70), anxiety symptoms (β = 0.11, 95%CI = −0.39, 0.60), or lower social support. Income inequality was not associated with community engagement. For the depression models, higher social support was significantly associated with lower depressive symptoms (β = −0.13, 95%CI = −0.15, −0.097), while community engagement was not significantly associated with depressive symptoms (β = 0.059, 95%CI = −0.15, 0.27). Similarly, for the anxiety models, lower anxiety symptoms were significantly associated with higher levels of social support (β = −0.17, 95%CI = −0.20, −0.13) but not with higher levels of community engagement (β = 0.14, 95%CI = −0.14, 0.41).ConclusionThe current study did not find clear evidence for social support or community engagement mediating the relationship between neighbourhood income inequality and maternal mental health. Future investigations should employ a broader longitudinal approach to capture changes in income inequality, potential mediators, and mental health symptomatology over time.     

眼表铁过载小鼠干眼模型的构建和机制研究

目的：通过给小鼠腹腔注射右旋糖酐铁，建立小鼠铁过载干眼模型并初步探索其可能的机制。

方法：将40只雄性C57BL/6小鼠(取右眼为实验眼)用随机数字表法将小鼠分为4组：对照组10只，每次腹腔注射生理盐水0.2mL； 低剂量组、中剂量组、高剂量组各10只为模型组，每次分别腹腔注射浓度为12.5、25、50mg/mL的右旋糖酐铁溶液0.2mL。每3d注射1次，共注射28d。注药后第7、14、28d观察各组小鼠眼表炎症指数、角膜荧光素染色、泪膜破裂时间(BUT)及泪液分泌量(SⅠt)，评估干眼及眼表炎症程度。28d后处死小鼠，取角膜、结膜及泪腺组织，进行HE染色、普鲁士蓝染色以及组织铁检测，评估小鼠炎症反应及铁过载情况； 采用酶联免疫吸附试验(ELISA)检测炎症因子白细胞介素-1β(IL-1β)、肿瘤坏死因子-α(TNF-α)、基质金属蛋白酶-9(MMP-9)的表达情况。

结果：与对照组相比，模型组小鼠出现一系列干眼症状，小鼠眼表炎症指数增高，角膜荧光素染色评分增加，BUT缩短，泪液分泌量减少(均P<0.05)； 模型组小鼠角膜、结膜及泪腺组织均受到不同程度的损伤，各组织眼表铁沉积情况较对照组加重，组织铁含量明显增加(均P<0.01)； 模型组小鼠角膜、结膜及泪腺组织中炎症因子(IL-1β、TNF-α、MMP-9)的含量均高于对照组(均P<0.01)，随着右旋糖酐铁注药时间及浓度增加，小鼠干眼及眼表炎症程度逐渐加重。

结论：腹腔注射右旋糖酐铁可成功建立小鼠铁过载干眼模型，其机制可能与铁过载加重眼表炎症反应有关。     

Establishment of an Evaluation Method for Gene Silencing by Serial Pulmonary Administration of siRNA and pDNA Powders: Naked siRNA Inhalation Powder Suppresses Luciferase Gene Expression in the Lung

In order to evaluate the in vivo effect of inhaled formulations, it is a gold standard to create a lung metastasis model by intravenously injecting cancer cells into an animal. Because the cancer grows from the blood vessel side, there is a possibility of underestimating the effect of an inhaled formulation administered to the lung epithelium side. In addition, the metastasis model has disadvantages in terms of preparation time and expense. The present study aimed to establish a new method to evaluate the effect of an inhaled small interfering RNA (siRNA) formulation that is more correct, more rapid, and less expensive. We investigated whether siRNA can suppress gene expression of plasmid DNA (pDNA) by serial pulmonary administration of siRNA and pDNA powders prepared by spray-freeze-drying. We revealed that formulations of dry siRNA powder significantly suppressed gene expression of pDNA powder compared with a control group with no siRNA. Naked siRNA inhalation powder with no vector showed the suppression of gene expression equivalent to that of an siRNA-polyethyleneimine complex without damaging tissues. These results show that the present method is suitable for evaluating the gene-silencing effect of inhaled siRNA powders.     

Symptom improvement in dry eye subjects following intranasal tear neurostimulation: Results of two studies utilizing a controlled adverse environment

PurposeTo evaluate the safety and effectiveness of the intranasal tear neurostimulator (ITN) in improving dry eye symptoms assessed in a controlled adverse environment (CAE®).MethodsStudy 1: Multicenter, subject-masked, randomized-sequence, crossover design. Single intranasal (active) and extranasal (control) ITN administration during CAE exposure. Study 2: Single-arm, open-label design. Intranasal ITN administration ≥2 times/day for 45 days, CAE assessment at days 0 and 45. In both studies, upon CAE entry, and every 5 min thereafter, subjects assessed eye dryness score (visual analog scale, 0–100 mm; EDS-VAS), and ocular discomfort score (ODS; Ora Calibra™, 0–4), for ≈2 h. Study 1: when ODS was ≥3 at 2 consecutive timepoints, subjects applied ITN intranasally or extranasally for ≈3 min, and again when achieving the same ODS criteria in randomized sequence. Study 2: days 0 and 45, ITN was applied for ≈3 min employing the same ODS criteria as Study 1.ResultsStudy 1: Significantly greater pre- to post-application reductions in mean [SEM] EDS (−16.5 [1.7] vs −3.1 [1.7], P < 0.0001) and ODS (−0.93 [0.08] vs −0.34 [0.08], P < 0.0001; n = 143) with intranasal vs extranasal stimulation. Study 2: On day 0 (n = 52) and day 45 (n = 48), significant pre- to post-application reductions in mean [SEM] EDS (−15.9 [2.7] and −15.2 [2.4]; P < 0.0001), and ODS (−1.3 [0.2] and −1.3 [0.1]; P < 0.0001). Few device-related adverse events were reported, none serious.ConclusionsAcute symptom relief is significant with the ITN and remains undiminished after daily use.     

Consensus summary report for CEPI/BC March 12–13, 2020 meeting: Assessment of risk of disease enhancement with COVID-19 vaccines

A novel coronavirus (CoV), Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), emerged in late 2019 in Wuhan, China and has since spread as a global pandemic. Safe and effective vaccines are thus urgently needed to reduce the significant morbidity and mortality of Coronavirus Disease 2019 (COVID-19) disease and ease the major economic impact. There has been an unprecedented rapid response by vaccine developers with now over one hundred vaccine candidates in development and at least six having reached clinical trials. However, a major challenge during rapid development is to avoid safety issues both by thoughtful vaccine design and by thorough evaluation in a timely manner. A syndrome of “disease enhancement” has been reported in the past for a few viral vaccines where those immunized suffered increased severity or death when they later encountered the virus or were found to have an increased frequency of infection. Animal models allowed scientists to determine the underlying mechanism for the former in the case of Respiratory syncytial virus (RSV) vaccine and have been utilized to design and screen new RSV vaccine candidates. Because some Middle East respiratory syndrome (MERS) and SARS-CoV-1 vaccines have shown evidence of disease enhancement in some animal models, this is a particular concern for SARS-CoV-2 vaccines. To address this challenge, the Coalition for Epidemic Preparedness Innovations (CEPI) and the Brighton Collaboration (BC) Safety Platform for Emergency vACcines (SPEAC) convened a scientific working meeting on March 12 and 13, 2020 of experts in the field of vaccine immunology and coronaviruses to consider what vaccine designs could reduce safety concerns and how animal models and immunological assessments in early clinical trials can help to assess the risk. This report summarizes the evidence presented and provides considerations for safety assessment of COVID-19 vaccine candidates in accelerated vaccine development.