Multiphoton microscopy for pre-clinical evaluation of flow-diverter stents for treating aneurysms

BackgroundConventional histological analyses are the gold standard for the study of aneurysms and vascular pathologies in pre-clinical research. Over the past decade, in vivo and ex vivo imaging using multiphoton microscopy have emerged as powerful pre-clinical tools for detailed tissue analyses that can assess morphology, the extracellular matrix (ECM), cell density and vascularisation. Multiphoton microscopy allows for deeper tissue penetration with minor phototoxicity.ObjectiveThe present study aimed to demonstrate the current status of multimodality imaging, including multiphoton microscopy, for detailed analyses of neo-endothelialisation and ECM evolution after flow-diverter stent (FDS) treatment in an experimental rabbit model of aneurysms.MethodsMultiphoton microscopy tools for assessing autofluorescence and second harmonic generation (SHG) signals from biological tissues were used to evaluate the endovascular treatment of intracranial aneurysms in an animal model of aneurysms (pig, rabbit). Results from multiphoton microscopy were compared to those from standard histology, electronic and bright field microscopy.ConclusionsThe present study describes novel evaluation modes based on multiphoton microscopy for visualising tissue morphology (e.g., collagen, elastin, and cells) to qualify and quantify the extent of neo-intimal formation of covered arteries and device integration into the arterial wall using a rabbit model of intracranial aneurysms treated with FDS.     

Relationship between unhealthy sleep status and dry eye symptoms in a Japanese population: The JPHC-NEXT study

PurposeTo investigate whether and how unhealthy sleep habits (i.e., the frequency of difficulty falling or staying asleep, and the frequency of waking up tired) and the duration of sleep are related to the prevalence of dry eye disease (DED) in a general population.MethodsThis study included a total of 106,282 subjects aged 40–74 years who participated in a baseline survey of the Japan Public Health Center-based Prospective Study for the Next Generation. DED was defined as the presence of clinically diagnosed DED or severe symptoms. Multivariable-adjusted logistic regression models were used to assess the relationships of various components of sleep status with DED.ResultsHigher frequencies of having difficulty falling or staying asleep, and waking up tired were significantly related to increased DED in both sexes (P_trend<0.001). Compared with those with 8 h/day of sleep, shorter sleepers had an increased prevalence of DED in both sexes, although DED was increased among men who slept ≥10 h/day. By comparing participants with the greatest vs. the least difficulty of falling asleep, the multivariable-adjusted odds ratios (95% confidence interval [CI]) were 2.23 (95% CI, 1.99–2.49) for men and 1.91 (95% CI, 1.76–2.07) for women. When analyzed separately, the magnitude of each relationship was stronger with severe DED symptoms than with clinically diagnosed DED.ConclusionsSleep deprivation and poor sleep quality were significantly related to DED in a Japanese population.     

Nicotine does not affect stem cell properties requisite for suicide gene therapy against glioma

ABSTRACT

Objective: 

Glioblastoma is one of the most lethal tumors in adult central nervous system with a median survival of a year and half and effective therapeutic strategy is urgently needed. For that reason, stem cell-based suicide gene therapies have attracted much interest because of potent tumor tropism of stem cells and bystander effect. In this current clinical situation, stem cells are promising delivery tool of suicide genes for glioma therapy. Since habitual cigarette smoking still prevails worldwide, we investigated the effect of nicotine on stem cell tropism toward glioma and gap junctional intercellular communication (GJIC) function between glioma and stem cells, both of which are important for suicide gene therapies. Methods: Mouse induced pluripotent stem cell-derived neural stem cells (iPS-NSCs) and human dental pulp mesenchymal stem cells (DPSCs) were used. The effect of nicotine on tumor tropism to glioma-conditioned medium (CM) at a non-cytotoxic concentration was assessed with Matrigel invasion assay. Nicotine effect on GJIC was assessed with the scrape loading/dye transfer (SL/DT) assay for co-culture of glioma and stem cells and the parachute assay among glioma cells using high-content analysis. Results: Tumor tropism of iPS-NSCs toward GL261-CM and DPSCs toward U251-CM was not affected by nicotine (0.1 and 1 µM). Nicotine at the concentrations equivalent to habitual smoking (1 µM) did not affect GJIC of iPS-NSC/GL261 and DPSC/U251 and GJIC among each glioma cells. Conclusions: The study demonstrated that non-cytotoxic concentrations of nicotine did not significantly change the stem cell properties requisite for stem cell-based suicide gene therapy.     

Arterial internal elastic lamina holes: relationship to function?

Internal elastic lamina (IEL) hole (fenestration) characteristics and myoendothelial gap junction (MEGJ) density were examined in selected resistance and conduit arteries of normal and diseased rat and mouse models, using conventional, ultrastructural and confocal microscopy methods. Selected vessels were those commonly used in functional studies: thoracic aorta, proximal and distal mesenteric, caudal, saphenous, middle‐cerebral and caudal cerebellar artery. Rat and mouse strains and treatment groups examined were Dahl, Sprague Dawley, Wistar Kyoto, Wistar, spontaneously hypertensive (SHR), deoxycorticosterone (DOC) treated rat; and apolipoprotein E knockout, C57/BL6 and BALB/c mice. Vessel size (as IEL circumference), IEL hole and MEGJ density were quantified. In mesenteric arteries, the width of IEL holes and the percent of IEL occupied by holes were also determined. IEL hole density varied significantly within and between mesenteric artery beds, even among normotensive rat strains. Among the hypertensive rats (SHR and DOC), hole density in some vessels was higher in the normotensives than in the hypertensives within each strain, whereas in Dahl rats, hole density was similar between hypertensives and normotensives. Hole density was not correlated with the formation of intimal lesions in superior mesenteric artery. There was no positive general correlation between IEL hole and MEGJ density in resistance and conduit vessels. However, there was a positive correlation between the size of some resistance arteries and MEGJ density, although such a relationship did not hold for conduit vessels or during development, and there was no such relationship between vessel size and IEL hole density. Whilst IEL holes are obviously required for MEGJ communication, their presence is not an indication of contact‐mediated communication, but rather may be related to the presence of sites for the low resistance passage of diffusion‐mediated release of vasoactive endothelial and smooth muscle substances.     

Endocrinology of bone mineralization: An update

Throughout the world, millions of people suffer from fragilizing osteopathies such as osteomalacia and osteoporosis. Osteomalacia is a rare disorder, corresponding to mineralization abnormalities in adult bone, as opposed to rickets in children. Renal phosphate loss and hypophosphatasia are the main causes of vitamin-resistant osteomalacia. Diagnosis is based on clinical history, phosphocalcic metabolism assessment and, if necessary, molecular characterization, and must be rapid in order to initiate the most appropriate treatment and consider new treatments such as burosumab if necessary. Osteoporosis is characterized by reduced bone mass and strength, which increases the risk of fragility fracture. Fracture-related burden is expected to increase over the coming decades linked to the aging of population and a treatment gap. In order to reduce this treatment gap, it is important to develop two strategies: improvement of screening and of treatment. Systematic screening using the FRAX® fracture risk assessment tool could be useful to increase anti-osteoporosis medical treatment and reduce fracture rates. The question of treatment sequencing in osteoporosis is another challenge, notably after denosumab cessation, complicated by a decrease in bone mineral density and increased risk of fracture. New treatments are also available, including romosozumab, a humanized monoclonal antibody, which promotes bone formation and inhibits bone resorption by inhibiting sclerostin. Romosozumab is approved in several countries, including France, for treating severe osteoporosis in postmenopausal women at high risk of fracture and free of cardiovascular comorbidity. Endocrinologists need to be aware of these fragilizing osteopathies in order to improve both diagnosis and treatment.     

A gap in formal long-term care use related to characteristics of caregivers and households,under the public universal system in Japan: 2001–2010

We investigated whether the universal provision of long-term care (LTC) under Japan's public system has equalized its use across households with different socio-economic characteristics, with a special focus on the gender and marital status of primary caregivers, and income. We used repeated cross-sectional data from national household surveys (2001, 2004, 2007, and 2010) and conducted multiple logistic regression analyses to obtain odds ratios of caregiver and household characteristics for service use, adjusting for recipients’ characteristics. The results showed that the patterns of service use have been consistently determined by caregivers’ gender and marital status over the period despite demographic changes among caregivers. The gap in service use first narrowed, then widened again across income levels after the global economic recession. The results indicate that the traditional gender-bound norms and capacity constraints on households’ informal care provision remained influential on decisions over service use, even after the universal provision of formal care. To improve equality of service utilization, the universal LTC system needs to meet diversifying needs of caregivers/recipients and their households, by overcoming barriers related to gender norms and economic disparity.     

Genomics-based Approach and Prognostic Stratification Significance of Gene Mutations in Intermediate-risk Acute Myeloid Leukemia

Objective:

Intermediate-risk acute myeloid leukemia (IR-AML), which accounts for a substantial number of AML cases, is highly heterogeneous. We systematically summarize the latest research progress on the significance of gene mutations for prognostic stratification of IR-AML.

Data Sources:

We conducted a systemic search from the PubMed database up to October, 2014 using various search terms and their combinations including IR-AML, gene mutations, mutational analysis, prognosis, risk stratification, next generation sequencing (NGS).

Study Selection:

Clinical or basic research articles on NGS and the prognosis of gene mutations in IR-AML were included.

Results:

The advent of the era of whole-genome sequencing has led to the discovery of an increasing number of molecular genetics aberrations that involved in leukemogenesis, and some of them have been used for prognostic risk stratification. Several studies have consistently identified that some gene mutations have prognostic relevance, however, there are still many controversies for some genes because of lacking sufficient evidence. In addition, tumor cells harbor hundreds of mutated genes and multiple mutations often coexist, therefore, single mutational analysis is not sufficient to make accurate prognostic predictions. The comprehensive analysis of multiple mutations based on sophisticated genomic technologies has raised increasing interest in recent years.

Conclusions:

NGS represents a pioneering and helpful approach to prognostic risk stratification of IR-AML patients. Further large-scale studies for comprehensive molecular analysis are needed to provide guidance and a theoretical basis for IR-AML prognostic stratification and clinical management.