Effect of omega-3 fatty acids on cardiovascular events in high-risk patients with hypertriglyceridemia in Japan: a 3-year post-marketing surveillance study (OCEAN3 survey).

BACKGROUND: Studies on the efficacy of prescription omega-3 polyunsaturated fatty acids to reduce cardiovascular events have produced conflicting results. RESEARCH DESIGN AND METHODS: This 3-year prospective post-marketing surveillance study evaluated the effect of omega-3-acid ethyl esters (O3AEE; usual dosage 2 g/day) on cardiovascular events in high-risk statin-treated Japanese patients with hypertriglyceridemia. Statin-treated patients not receiving O3AEE were included as a reference cohort. The composite primary endpoint was cardiovascular death, myocardial infarction, stroke, angina requiring coronary revascularization, or peripheral arterial disease requiring surgery or peripheral arterial intervention. RESULTS: At 3 years, Kaplan-Meier estimated cumulative incidence of the primary endpoint was 2.5% (95% confidence interval, 2.1%-2.9%) in O3AEE-treated patients (N = 6,580) and 2.7% (2.4%-3.1%) in non-O3AEE-treated patients (N = 7,784; hazard ratio, 0.99; 95% confidence interval, 0.79-1.23). Incidence of heart failure requiring hospitalization was 0.4% with O3AEE versus 0.8% in non-O3AEE-treated patients (hazard ratio, 0.47; 95% confidence interval, 0.28-0.78; P < 0.05). CONCLUSIONS: Among patients receiving statins, cardiovascular event incidence did not differ significantly between O3AEE-treated patients and non-O3AEE-treated patients. Further studies are required before definitive conclusions can be drawn on the effect of O3AEE on cardiovascular event incidence in high-risk patients with hypertriglyceridemia. TRIAL REGISTRATION: ClinicalTrials.gov, NCT02285166.

c-Src-mediated phosphorylation and activation of kinesin KIF1C promotes elongation of invadopodia in cancer cells.

Invadopodia on cancer cells play crucial roles in tumor invasion and metastasis by degrading and remodeling the surrounding extracellular matrices and driving cell migration in complex 3D environments. Previous studies have indicated that microtubules (MTs) play a crucial role in elongation of invadopodia, but not their formation, probably by regulating delivery of membrane and secretory proteins within invadopodia. However, the identity of the responsible MT-based molecular motors and their regulation has been elusive. Here, we show that KIF1C, a member of kinesin-3 family, is localized to the tips of invadopodia and is required for their elongation and the invasion of cancer cells. We also found that c-Src phosphorylates tyrosine residues within the stalk domain of KIF1C, thereby enhancing its association with tyrosine phosphatase PTPD1, that in turn activates MT-binding ability of KIF1C, probably by relieving the autoinhibitory interaction between its motor and stalk domains. These findings shed new insights into how c-Src signaling is coupled to the MT-dependent dynamic nature of invadopodia and also advance our understanding of the mechanism of KIF1C activation through release of its autoinhibition.

Transfected plasmid DNA is incorporated into the nucleus via nuclear envelope reformation at telophase.

DNA transfection is an important technology in life sciences, wherein nuclear entry of DNA is necessary to express exogenous DNA. Non-viral vectors and their transfection reagents are useful as safe transfection tools. However, they have no effect on the transfection of non-proliferating cells, the reason for which is not well understood. This study elucidates the mechanism through which transfected DNA enters the nucleus for gene expression. To monitor the behavior of transfected DNA, we introduce plasmid bearing lacO repeats and RFP-coding sequences into cells expressing GFP-LacI and observe plasmid behavior and RFP expression in living cells. RFP expression appears only after mitosis. Electron microscopy reveals that plasmids are wrapped with nuclear envelope (NE)‒like membranes or associated with chromosomes at telophase. The depletion of BAF, which is involved in NE reformation, delays plasmid RFP expression. These results suggest that transfected DNA is incorporated into the nucleus during NE reformation at telophase.

Carotid ultrasonography predicts collateral development following combined direct and indirect revascularization surgery in adult ischemic Moyamoya disease.

OBJECTIVE: The relationship between carotid ultrasonographic parameters and postoperative collateral development in adult ischemic moyamoya disease (MMD) patients who received combined direct and indirect revascularization surgery remains unclear. Herein, we investigated the postoperative changes in carotid ultrasonographic parameters in patients with adult ischemic MMD. METHODS: We studied 28 adult ischemic MMD patients (31 hemispheres) who underwent combined revascularization surgery. Patients underwent preoperative and postoperative (within 14 days and 3, 12, and 24 months after surgery) magnetic resonance imaging and carotid ultrasonography. We defined the hemisphere in which all signal intensities of the superficial temporal, middle meningeal, and deep temporal arteries were increased compared with that before surgery on magnetic resonance angiography as well-developed collateral establishment. RESULTS: Patients with good collateral establishment on MRA at 2-year after surgery had a lower external carotid artery (ECA) pulsatility index (PI) (P = 0.0413) and ECA/internal carotid artery (ICA) pulsatility index (PI) ratio (P = 0.0427) at 3-month post-operation. At 3-month post-operation, a cut-off ECA PI of 1.416 (sensitivity 40.0 %, specificity 92.3 %, area under the curve 0.7282, likelihood ratio 5.20, P = 0.0404) and ECA/ICA PI ratio of 0.8768 (sensitivity 50.0 %, specificity 92.31 %, area under the curve 0.7308, likelihood ratio 6.50, P = 0.0415) provided reliable values for good prediction of collateral development at 2 years after revascularization. CONCLUSION: ECA/ICA PI ratio and ECA PI at 3-month after surgery can be one of the indicators for predicting future well-developed neovascularization on MRA and better outcome in patients with adult ischemic MMD who received combined direct and indirect revascularization surgery.

NUDT21 Links Mitochondrial IPS-1 to RLR-Containing Stress Granules and Activates Host Antiviral Defense.

Viral RNA in the cytoplasm of mammalian host cells is recognized by retinoic acid-inducible protein-I-like receptors (RLRs), which localize to cytoplasmic stress granules (SGs). Activated RLRs associate with the mitochondrial adaptor protein IPS-1, which activates antiviral host defense mechanisms, including type I IFN induction. It has remained unclear, however, how RLRs in SGs and IPS-1 in the mitochondrial outer membrane associate physically and engage in information transfer. In this study, we show that NUDT21, an RNA-binding protein that regulates alternative transcript polyadenylation, physically associates with IPS-1 and mediates its localization to SGs in response to transfection with polyinosinic-polycytidylic acid [poly(I:C)], a mimic of viral dsRNA. We found that despite its well-established function in the nucleus, a fraction of NUDT21 localizes to mitochondria in resting cells and becomes localized to SGs in response to poly(I:C) transfection. NUDT21 was also found to be required for efficient type I IFN induction in response to viral infection in both human HeLa cells and mouse macrophage cell line RAW264.7 cells. Our results together indicate that NUDT21 links RLRs in SGs to mitochondrial IPS-1 and thereby activates host defense responses to viral infection.

Ischemic Stroke Caused by Carotid Stump at the Common Carotid Artery.

An 84-year-old man developed motor aphasia and right hemiparesis on postoperative day 1 after orchiectomy for suspected malignant lymphoma. He had a history of thoracic endovascular aortic repair for aortic aneurysm using a bypass graft from the right subclavian artery to the left common carotid artery (CCA); however, the graft had become occluded six months later. Brain magnetic resonance imaging revealed acute cerebral infarctions in the left frontal lobe. Carotid ultrasonography revealed a stump at the left CCA, just below the bifurcation, formed by the occluded graft with an oscillating thrombus. This case was rare in that a CCA stump was identified as the embolic source of ischemic stroke.

Long-term Outcomes After Controlled Pericardial Drainage for Acute Type A Aortic Dissection.

BACKGROUND: Cardiac tamponade with acute aortic dissection type A can cause fatal outcomes. We previously reported excellent outcomes using percutaneous pericardial drainage with controlled volumes of aspirated pericardial effusion (controlled pericardial drainage [CPD]) to stabilize patients with critical cardiac tamponade. This study evaluates the early and late outcomes using this approach. METHODS: Between September 2003 and July 2018, 308 patients with acute aortic dissection type A were treated surgically, including 76 patients who presented with cardiac tamponade on hospital arrival. Forty-nine patients who did not respond to intravenous volume resuscitation underwent CPD in the emergency room, including 14 patients (28.6%) who presented with cardiopulmonary arrest. After CPD 39 patients (79.6%) were transferred to the operating room to undergo immediate aortic repair. The remaining 10 patients (20.4%) received medical treatment on arrival, followed by aortic repair within several days. RESULTS: In 49 patients the mean systolic blood pressure before CPD was 64.4 ± 10.3 mm Hg. Blood pressure rose significantly in all patients after CPD. The total volume of aspirated pericardial effusion was 46.8 ± 56.2 mL, and 30 of 49 patients (61%) required only 30 mL or less of aspiration to improve their blood pressure. All patients underwent successful aortic repair. Early hospital mortality was 16%. However there was no mortality related to CPD. The mean follow-up period was 52.9 ± 54.3 months. The cumulative survival rate was 63.4% after 5 years. CONCLUSIONS: CPD for critical cardiac tamponade with acute type A aortic dissection produced satisfactory early and late outcomes.

An improved fluorescent protein-based expression reporter system that utilizes bioluminescence resonance energy transfer and peptide-assisted complementation.

Fluorescent protein-based reporter systems are used to track gene expression in cells. Here, we propose a modified bioluminescence resonance energy transfer (BRET) reporter as a maturation-less reporter that utilizes a peptide-assisted complementation strategy. Using effective dimerized peptides obtained from library-versus-library screening with more than 4000 candidates, rapid activation of the reporter was achieved.

Management of Antithrombotic Agents During Surgery or Other Kinds of Medical Procedures With Bleeding: The MARK Study.

Background Optimal management of antithrombotic agents during surgery has yet to be established. We performed a prospective multicenter observational study to determine the current status of the management of antithrombotic agents during surgery or other medical procedures with bleeding (MARK [Management of Antithrombotic Agents During Surgery or Other Kinds of Medical Procedures With Bleeding] study) in Japan. Methods and Results The participants were 9700 patients who received oral antithrombotic agents and underwent scheduled medical procedures with bleeding at 59 National Hospital Organization institutions in Japan. Primary outcomes were thromboembolic events, bleeding events, and death within 2 weeks before and 4 weeks after the procedures. We investigated the relationships between each outcome and patient demographics, comorbidities, type of procedure, and management of antithrombotic therapy. With respect to the periprocedural management of antithrombotic agents, 3551 patients continued oral antithrombotic agents (36.6%, continuation group) and 6149 patients discontinued them (63.4%, discontinuation group). The incidence of any thromboembolic event (1.7% versus 0.6%, P<0.001), major bleeding (7.6% versus 0.4%, P<0.001), and death (0.8% versus 0.4%, P<0.001) was all greater in the discontinuation group than the continuation group. In multivariate analysis, even after adjusting for confounding factors, discontinuation of anticoagulant agents was significantly associated with higher risk for both thromboembolic events (odds ratio: 4.55; 95% CI, 1.67-12.4; P=0.003) and major bleeding (odds ratio: 11.1; 95% CI, 2.03-60.3; P=0.006) in procedures with low bleeding risk. In contrast, heparin bridging therapy was significantly associated with higher risk for both thromboembolic events (odds ratio: 2.03; 95% CI, 1.28-3.22; P=0.003) and major bleeding (odds ratio: 1.36; 95% CI, 1.10-1.68; P=0.005) in procedures with high bleeding risk. Conclusions Discontinuation of oral antithrombotic agents and addition of low-dose heparin bridging therapy appear to be significantly associated with adverse events in the periprocedural period.

[Case report: transient ischemic stroke caused by internal carotid artery occlusion due to compression by pituitary apoplexy and hemodynamic mechanism].

An 87-year-old blind man was admitted due to repeatedly disturbed consciousness and fever. Brain CT showed a pituitary tumor with a hematoma and an occlusive lesion of the right internal carotid artery. He experienced consciousness disturbance and left limb weakness with hypotension for a few minutes on the day of admission. We considered pituitary apoplexy caused adrenal failure with hypotension and transient ischemic attack (TIA) induced by a hemodynamic mechanism. An increased dose of hydrocortisone improved the fever and hypotension, and resolved consciousness disturbance. This is a unique example of TIA caused by the occlusive lesion of the internal carotid artery compressed as a result of pituitary apoplexy and a hemodynamic mechanism.

Japanese Versus Non-Japanese Patients with Transient Ischemic Attack or Minor Stroke: Subanalysis of TIA registry.org.

BACKGROUND: TIAregistry.org is an international cohort of patients with transient ischemic attack (TIA) or minor stroke within 7 days before enrollment in the registry. Main analyses of 1-year follow-up data have been reported.5 We conducted subanalysis on the baseline and 1-year follow-up data of Japanese patients. METHODS: The patients were classified into 2 groups based on Japanese ethnicity, Japanese (345) and non-Japanese (3238), and their baseline data and 1-year event rates were compared. We also determined risk factors and predictors of 1-year stroke. RESULTS: Current smoking, regular alcohol drinking, intracranial arterial stenosis, and small vessel occlusion; and hypertension, dyslipidemia, coronary artery disease, and extracranial arterial stenosis were more and less common among Japanese patients, respectively. Stroke risk was higher and TIA risk was lower at 1-year follow-up among Japanese patients. The baseline risk factors for recurrent stroke were diabetes, alcohol drinking, and large artery atherosclerosis. Independent predictors of 1-year stroke risk were prior congestive heart failure and alcohol consumption. CONCLUSIONS: The two populations of patients featured differences in risk factors, stroke subtypes, and outcome events. Predictors of recurrent stroke among Japanese patients included congestive heart failure and regular alcohol drinking. Strategies to attenuate residual risk of stroke aside from adherence to current guidelines should take our Japanese-patient specific findings into account.

Investigation of multiple-dynein transport of melanosomes by non-invasive force measurement using fluctuation unit χ.

Pigment organelles known as melanosomes disperse or aggregate in a melanophore in response to hormones. These movements are mediated by the microtubule motors kinesin-2 and cytoplasmic dynein. However, the force generation mechanism of dynein, unlike that of kinesin, is not well understood. In this study, to address this issue, we investigated the dynein-mediated aggregation of melanosomes in zebrafish melanophores. We applied the fluctuation theorem of non-equilibrium statistical mechanics to estimate forces acting on melanosomes during transport by dynein, given that the energy of a system is related to its fluctuation. Our results demonstrate that multiple force-producing units cooperatively transport a single melanosome. Since the force is generated by dynein, this suggests that multiple dyneins carry a single melanosome. Cooperative transport has been reported for other organelles; thus, multiple-motor transport may be a universal mechanism for moving organelles within the cell.

Kinesin-binding-triggered conformation switching of microtubules contributes to polarized transport.

Kinesin-1, the founding member of the kinesin superfamily of proteins, is known to use only a subset of microtubules for transport in living cells. This biased use of microtubules is proposed as the guidance cue for polarized transport in neurons, but the underlying mechanisms are still poorly understood. Here, we report that kinesin-1 binding changes the microtubule lattice and promotes further kinesin-1 binding. This high-affinity state requires the binding of kinesin-1 in the nucleotide-free state. Microtubules return to the initial low-affinity state by washing out the binding kinesin-1 or by the binding of non-hydrolyzable ATP analogue AMPPNP to kinesin-1. X-ray fiber diffraction, fluorescence speckle microscopy, and second-harmonic generation microscopy, as well as cryo-EM, collectively demonstrated that the binding of nucleotide-free kinesin-1 to GDP microtubules changes the conformation of the GDP microtubule to a conformation resembling the GTP microtubule.

Improvement and Aggravation of Spontaneous Unruptured Vertebral Artery Dissection.

BACKGROUND: Intracranial vertebral artery dissection (VAD) is a well-recognized cause of stroke in young and middle-aged individuals, especially in Asian populations. However, a long-term natural course remains unclear. We investigated the long-term time course of VAD using imaging findings to examine the rate and predisposing factors for improvement. METHODS: We registered 56 consecutive patients (40 males; mean age, 51.8 ± 10.7 years) with acute spontaneous VAD and retrospectively investigated neuroimaging and clinical course within 1 month and at 3 months ± 2 weeks, 6 months ± 2 weeks, and 12 months ± 2 weeks after onset to ascertain predisposing factors and time course for improvement. RESULTS: The most common presenting symptoms were headache and/or posterior neck pain, seen in 41 patients (73%). Magnetic resonance imaging showed brainstem and/or cerebellum infarction in only 32 patients (57%). Of the 56 VADs, 16 (28%) presented with pearl and string sign, 5 (9%) with pearl sign, 15 (27%) with string sign, and 20 (36%) with occlusion sign. VAD occurred on the dominant side in 20 patients and on the nondominant side in the other 36 patients. The pearl and string sign was more frequently noted on the dominant side than on the nondominant side (50 vs. 17%, p = 0.008). On the other hand, occlusion occurred more often on the nondominant side than on the dominant side (47 vs. 15%, p = 0.016). Furthermore, the pearl and string sign was more frequently seen in the improvement group (41 vs. 15%, p = 0.028), whereas the occlusion sign was evident more frequently in the nonimprovement group (21 vs. 52%, p = 0.015). Follow-up neuroimaging evaluation was performed at 1 and 3 months in 91% each, and at 6 and 12 months in 82% each. VAD aggravation was identified within 1 month after onset in 14%, while VAD improvement was seen in 14, 38, 50, and 52% at each period, mainly within 6 months after onset. Older patients and current smoking were negatively associated with VAD improvement. CONCLUSIONS: VAD improvement primarily occurs within 6 months after onset, and VAD aggravation within 1 month. It seems that older patients and current smoking are negative predictors of VAD improvement as risk factors, and as image findings, the pearl and string sign is a positive predictor and occlusion a negative predictor.

Causes of Ischemic Stroke in Patients with Non-Valvular Atrial Fibrillation.

BACKGROUND: Oral anticoagulants (OACs) reduce the incidence of embolic events associated with non-valvular atrial fibrillation (NVAF); however, ischemic stroke can still occur in such patients. Although there are various causes of ischemic stroke in patients with NVAF, their medication status at onset has scarcely been studied. This retrospective study aimed to determine the underlying causes of ischemic stroke in patients with NVAF in relation to pre-stroke anticoagulation. METHODS: Among Japanese patients with acute ischemic stroke enrolled in the Fukuoka Stroke Registry from June 2007 to May 2013, 1,302 patients with NVAF who had been hospitalized within 24 h of onset were included in this study, and their backgrounds, pre-stroke use of OACs and prothrombin time-international normalized ratio (PT-INR) on admission were investigated. Strokes were regarded as being non-cardioembolic (CE) type when causes other than NVAF had been identified. The sub-therapeutic range (TR) for warfarin was defined according to Japanese guidelines for pharmacotherapy of atrial fibrillation. RESULTS: Atrial fibrillation had been diagnosed prior to onset of stroke in 704 of 1,302 patients (54%). However, it had not been detected before or on admission, but identified later during hospitalization in 270 patients (21%). Of the patients who had atrial fibrillation on admission but had not been diagnosed as having it, 108 (8%) had not received any medication before onset of stroke and 220 (17%) had received medications other than OACs. OACs had been administered to 415 (59%) of the patients with known atrial fibrillation. The proportion of pre-stroke CHADS2 or CHA2DS2-VASc scores ≥1 ranged from 93 to 99% depending on whether atrial fibrillation had been diagnosed or anticoagulation therapy administered before stroke onset. The PT-INR was in the sub-TR on admission in 283 of 399 patients (71%) receiving warfarin. Male sex, smoking and previous stroke were more prevalent in patients with values within or over the TR of PT-INR than in those in the sub-TR. Non-CE stroke was more prevalent in patients with values above the lower therapeutic limit of the recommended PT-INR than in those in the sub-TR (p < 0.001). The number of CE strokes was much smaller in patients with high admission PT-INR values; this was not observed for non-CE ischemic strokes (p < 0.001). CONCLUSIONS: In the clinical setting, under-diagnosis, underuse and sub-therapeutic doses of OACs are major causes of ischemic stroke in patients with NVAF. However, non-CE ischemic strokes may develop in patients receiving therapeutic doses of warfarin.

Dermatitis caused by metal allergy after coil embolization for unruptured cerebral aneurysm.

We report a rare case of metal-induced dermatitis after coil embolization for cerebral aneurysm. A 51-year-old woman experienced a rash around the lips and neck 3 weeks after coil embolization. Judging from the clinical course and results of several patch tests, platinum coils were considered to have induced the dermatitis. Symptoms were relieved with administration of oral steroids. This represents the first report of metal-induced dermatitis after neuroendovascular treatment. The possibility of metal allergy was difficult to suspect preoperatively. However, early evaluation and referral are important when skin symptoms are observed postoperatively.

The γ-tubulin-specific inhibitor gatastatin reveals temporal requirements of microtubule nucleation during the cell cycle.

Inhibitors of microtubule (MT) assembly or dynamics that target α/ß-tubulin are widely exploited in cancer therapy and biological research. However, specific inhibitors of the MT nucleator γ-tubulin that would allow testing temporal functions of γ-tubulin during the cell cycle are yet to be identified. By evolving ß-tubulin-binding drugs we now find that the glaziovianin A derivative gatastatin is a γ-tubulin-specific inhibitor. Gatastatin decreased interphase MT dynamics of human cells without affecting MT number. Gatastatin inhibited assembly of the mitotic spindle in prometaphase. Addition of gatastatin to preformed metaphase spindles altered MT dynamics, reduced the number of growing MTs and shortened spindle length. Furthermore, gatastatin prolonged anaphase duration by affecting anaphase spindle structure, indicating the continuous requirement of MT nucleation during mitosis. Thus, gatastatin facilitates the dissection of the role of γ-tubulin during the cell cycle and reveals the sustained role of γ-tubulin.

Safety and Management of Antithrombotic Therapy with Intra-Arterial Catheter Procedures.

OBJECTIVE: Intravascular catheter procedures are often performed in patients undergoing antithrombotic therapy. However, methods for the management of antithrombotic agents in the perioperative period are currently unclear. Therefore, the safety and management of antithrombotic agents in these patients were investigated. METHODS: A prospective, multicenter, observational study [Management of Antithrombotic Agents During Surgery or Medical Procedures with Bleeding (MARK study)] at 58 National Hospital Organization institutions in Japan was performed. 1,040 patients were enrolled in the MARK study and underwent an intravascular catheter procedure. For all participants, the details of the procedure, method of perioperative management of antithrombotic agents, and occurrence of thrombosis, embolism, and bleeding complications during the study period were investigated. RESULTS: The use of antithrombotic agents was continued in 1,017 patients (98%, continuation group) and discontinued in the other 23 (2%, discontinuation group). Continuation of the antithrombotic agents did not have a significant effect on the overall occurrence of thromboembolism [hazard ratio (HR), 0.15; p=0.08] or bleeding events (HR, 0.19; p=0.12). However, the overall adverse event risk was significantly lower in the continuation group than in the discontinuation group (HR, 0.18; p=0.03). CONCLUSION: It is both safe and appropriate to perform intravascular catheter procedures in patients continuing with antithrombotic therapy.

Compact and stable SNAP ligand-conjugated quantum dots as a fluorescent probe for single-molecule imaging of dynein motor protein.

Compact SNAP ligand-conjugated quantum dots (<10 nm) with high colloidal stability over a wide range of pH (5-9) have been synthesized as fluorescent probe for the single-molecule imaging of dynein motor protein.