Theoretical study on the need for laser iridotomy in an implantable collamer lens with a hole using computational fluid dynamics

PurposeAlthough one of the advantages of the Hole-ICL implantation is that laser iridotomy (LI) is unnecessary, the evidence have not been reported from the viewpoint of aqueous humor circulation. We investigated the effect of laser iridotomy (LI) on the fluid dynamics of aqueous humor in an implantable collamer lens (ICL) with a central hole, that is, a Hole-ICL using computational fluid dynamics.MethodsA fluid dynamics simulation was performed using the thermal-hydraulic analysis software FloEFD (Mentor Graphics Corp.). For the simulation, three-dimensional eye models with a conventional ICL (Model ICM, STAAR SURGICAL) and a Hole-ICL were used. The LI diameters were 250 and 500 μm. The flow distribution between the anterior surface of the crystalline lens and the posterior surface of the ICL was also calculated.ResultsThe flow velocity 0.25 mm in front of the center of the crystalline lens in the Hole-ICL without LI, with LI of 250 μm, and with LI of 500 μm was 1.48 × 10^-1, 1.20 × 10^-1, and 4.52 × 10^-2 mm/s, respectively. The flow velocity in the conventional ICL without LI, with LI of 250 μm, and with LI of 500 μm was 1.21 × 10^-5, 3.60 × 10^-4, and 6.33 × 10^-4 mm/s, respectively.ConclusionsThese results suggest that there is less need for LI in a posterior chamber phakic intraocular lens with a central hole from the viewpoint of aqueous humor circulation, although the results can be considered only in an ideal condition and further studies are needed to clarify the effect of LI in clinical practice.

High efficiency penetration of antibody-immobilized nanoneedle thorough plasma membrane for in situ detection of cytoskeletal proteins in living cells

Background

The field of structural dynamics of cytoskeletons in living cells is gathering wide interest, since better understanding of cytoskeleton intracellular organization will provide us with not only insights into basic cell biology but may also enable development of new strategies in regenerative medicine and cancer therapy, fields in which cytoskeleton-dependent dynamics play a pivotal role. The nanoneedle technology is a powerful tool allowing for intracellular investigations, as it can be directly inserted into live cells by penetrating through the plasma membrane causing minimal damage to cells, under the precise manipulation using atomic force microscope. Modifications of the nanoneedles using antibodies have allowed for accurate mechanical detection of various cytoskeletal components, including actin, microtubules and intermediate filaments. However, successful penetration of the nanoneedle through the plasma membrane has been shown to vary greatly between different cell types and conditions. In an effort to overcome this problem and improve the success rate of nanoneedle insertion into the live cells, we have focused here on the fluidity of the membrane lipid bilayer, which may hinder nanoneedle penetration into the cytosolic environment.

Results

We aimed to reduce apparent fluidity of the membrane by either increasing the approach velocity or reducing experimental temperatures. Although changes in approach velocity did not have much effect, lowering the temperature was found to greatly improve the detection of unbinding forces, suggesting that alteration in the plasma membrane fluidity led to increase in nanoneedle penetration.

Conclusions

Operation at a lower temperature of 4 °C greatly improved the success rate of nanoneedle insertion to live cells at an optimized approach velocity, while it did not affect the binding of antibodies immobilized on the nanoneedle to vimentins for mechanical detection. As these experimental parameters can be applied to various cell types, these results may improve the versatility of the nanoneedle technology to other cell lines and platforms.

Electronic supplementary material

The online version of this article (doi:10.1186/s12951-016-0226-5) contains supplementary material, which is available to authorized users.

The longitudinal mental health impact of Fukushima nuclear disaster exposures and public criticism among power plant workers: the Fukushima NEWS Project study

BACKGROUND

The Fukushima Daiichi and Daini Nuclear Power Plant workers experienced multiple stressors as both victims and onsite workers after the 2011 Great East Japan Earthquake and subsequent nuclear accidents. Previous studies found that disaster-related exposures, including discrimination/slurs, were associated with their mental health. Their long-term impact has yet to be investigated.

METHOD

A total of 968 plant workers (Daiichi, n = 571; Daini, n = 397) completed self-written questionnaires 2-3 months (time 1) and 14-15 months (time 2) after the disaster (response rate 55.0%). Sociodemographics, disaster-related experiences, and peritraumatic distress were assessed at time 1. At time 1 and time 2, general psychological distress (GPD) and post-traumatic stress response (PTSR) were measured, respectively, using the K6 scale and Impact of Event Scale Revised. We examined multivariate covariates of time 2 GPD and PTSR, adjusting for autocorrelations in the hierarchical multiple regression analyses.

RESULTS

Higher GPD at time 2 was predicted by higher GPD at time 1 (β = 0.491, p < 0.001) and discrimination/slurs experiences at time 1 (β = 0.065, p = 0.025, adjusted R 2 = 0.24). Higher PTSR at time 2 was predicted with higher PTSR at time 1 (β = 0.548, p < 0.001), higher age (β = 0.085, p = 0.005), and discrimination/slurs experiences at time 1 (β = 0.079, p = 0.003, adjusted R 2 = 0.36).

CONCLUSIONS

Higher GPD at time 2 was predicted by higher GPD and discrimination/slurs experience at time 1. Higher PTSR at time 2 was predicted by higher PTSR, higher age, and discrimination/slurs experience at time 1.

Measurement of neutral gas pressure in the D-module of GAMMA 10/PDX by using ASDEX type fast ionization gauge

In the divertor simulation experiments in the GAMMA 10/PDX tandem mirror, pressure of the neutral gas was investigated by using a fast ionization gauge. The gauge was absolutely calibrated for hydrogen gas by using a capacitance manometer. Change of the gauge sensitivity due to the magnetic field of GAMMA 10/PDX was also evaluated. The typical gas pressure measured in detached plasma experiments was 0.1-10 Pa. The degree of plasma detachment determined from the reduction of heat flux was enhanced as the gas pressure increases. Rapid increase of the gas pressure under the plasma flow was also observed.

Electromagnetic Fields Inhibit Endothelin-1 Production Stimulated by Thrombin in Endothelial Cells

Electromagnetic field (EMF) radiation has been found to induce arteriolar dilatation, but the mechanism of action remains largely unknown. This study investigated the effect of EMF radiation on the production of endothelin-1 (ET-1), a potent vasoconstrictor, by cultured endothelial cells. EMF radiation reduced ET-1 basal levels in human umbilical vein and microvascular endothelial cells, but failed to reduce ET-1 basal levels in bovine and human aortic endothelial cells. EMF radiation significantly inhibited thrombin-stimulated ET-1 production in all four endothelial cell types in a dose-dependent manner. EMF radiation significantly inhibited thrombin-induced endothelin-1 mRNA expression in all four cell types. The inhibitory effect of EMF radiation on ET-1 production was abolished by the nitric oxide synthase inhibitor NG-monomethyl-L-arginine (10−3 mol/l). These results demonstrate that EMF radiation modulates ET-1 production in cultured vascular endothelial cells and the inhibitory effect of EMF radiation is, at least partly, mediated through a nitric oxide-related pathway.

Angiographic A-V Shunt during Interventional Thrombolysis for Acute Cerebral Embolism

In order to predict the post-therapeutic hemorrhagic complication of interventional thrombolysis, we retrospectively examined angiographic findings and other factors in 44 patients with acute cerebral embolism. All patients were super selectively catheterized within 5 hours of onset and received a fixed regimen of urokinase or t-PA, unless recanalization was achieved or deterioration was apparent before total infusion. Immediate post-therapeutic CT scan revealed hematoma within the basal ganglia in 10 patients (group 1) and no hemorrhage in the remaining 34 (group 2). A series of angiograms during the therapy showed A-V shunt from lenticulostriate arteries to thalamostriate vein in 7 of 10 cases in group 1; no case in group 2 was accompanied by such abnormal shunt.

Prognosis after the therapy was worse in group 1 than in group 2. No other factors, such as therapeutic timing after the disease onset or total doses of urokinase or t-PA infused, differed between the two groups. These findings indicate that angiographic A-V shunt during therapy is a predictive sign of a high incidence of hemorrhagic complication.

We recommend performing several angiographic controls during therapy and when A-V shunt is detected, the therapy should be discontinued to prevent hemorrhage which leads to a poor prognosis.

[Influence of an Operative Strategy on Outcomes of Acute Type A Aortic Dissection Cases]

OBJECTIVE

To compare the surgical outcomes of total arch replacement with the outcomes of ascending aorta replacement in patients with acute Stanford type A aortic dissection.

METHODS

From April 2002 to May 2014, 90 patients with acute Stanford type A aortic dissection underwent emergency surgical treatment at our institution. Among them, 16 underwent total arch replacement and 74 underwent ascending aorta replacement. The decision to perform total arch versus ascending aorta replacement was dependent on an intimal tearing site.

RESULTS

There were no statistically significant differences in characteristics between the groups with regard to the 2 surgical procedures. Twenty early deaths were reported, but there was no statistically significant difference in mortality rate between the groups. The aortic operation had to be redone in 12 patients. The reoperations were not associated with an increased risk of death or neurological complications. Overall 5-year survival rates were 68% in the ascending aorta replacement group and 59% in the total arch replacement group. There was no statistically significant difference between the groups.

CONCLUSIONS

The surgical outcome and prognosis of ascending aorta replacement is satisfactory among patients undergoing treatment of acute type A aortic dissection.

Fermented milk containing Lactobacillus casei strain Shirota prevents the onset of physical symptoms in medical students under academic examination stress

This pilot study investigated the effects of the probiotic Lactobacillus casei strain Shirota (LcS) on psychological, physiological, and physical stress responses in medical students undertaking an authorised nationwide examination for promotion. In a double-blind, placebo-controlled trial, 24 and 23 healthy medical students consumed a fermented milk containing LcS and a placebo milk, respectively, once a day for 8 weeks until the day before the examination. Psychophysical state, salivary cortisol, faecal serotonin, and plasma L-tryptophan were analysed on 5 different sampling days (8 weeks before, 2 weeks before, 1 day before, immediately after, and 2 weeks after the examination). Physical symptoms were also recorded in a diary by subjects during the intervention period for 8 weeks. In association with a significant elevation of anxiety at 1 day before the examination, salivary cortisol and plasma L-tryptophan levels were significantly increased in only the placebo group (P<0.05). Two weeks after the examination, the LcS group had significantly higher faecal serotonin levels (P<0.05) than the placebo group. Moreover, the rate of subjects experiencing common abdominal and cold symptoms and total number of days experiencing these physical symptoms per subject were significantly lower in the LcS group than in the placebo group during the pre-examination period at 5-6 weeks (each P<0.05) and 7-8 weeks (each P<0.01) during the intervention period. Our results suggest that the daily consumption of fermented milk containing LcS may exert beneficial effects preventing the onset of physical symptoms in healthy subjects exposed to stressful situations.