Comparison of the tidal volume by the recruitment maneuver combined with positive end-expiratory pressure for mechanically ventilated children.

The recruitment maneuver (RM) combined with PEEP to prevent atelectasis have beneficial effects. However, the change in tidal volume (VT) due to RM combined with PEEP in pediatric patients during the induction of general anesthesia is unknown. Therefore, we assessed the effects of RM combined with PEEP on VT. Pediatric patients were divided into three groups: infants, preschool children, and school children. The RM was performed by maintaining pressure control continuous mandatory ventilation (PC-CMV) with a 15 cmH2O and PEEP increase of 5 cmH2O. VT, respiratory function and hemodynamics were monitored before and after RM combined with PEEP. VT (mL) /ideal body weight (kg) before vs. after RM combined with PEEP were 9 vs 12 mL/kg (p < 0.05) in the infants, 9 vs 11 mL/kg (p < 0.05) in the preschool children, 8 vs 10 mL/kg (p < 0.05) in the school children, respectively. HR and BP before and after RM combined with PEEP increased by 2-3% and decreased by 4-7% in all groups. RM combined with PEEP resulted in an increase in VT per ideal body weight (1.1-1.2%). Therefore, this RM combined with PEEP method might improve the lung function in pediatric patients.

A cyclic pyrrole-imidazole polyamide reduces pathogenic RNA in CAG/CTG triplet repeat neurological disease models.

Expansion of CAG and CTG (CWG) triplet repeats causes several inherited neurological diseases. The CWG repeat diseases are thought to involve complex pathogenic mechanisms through expanded CWG repeat-derived RNAs in a noncoding region and polypeptides in a coding region, respectively. However, an effective therapeutic approach has not been established for the CWG repeat diseases. Here, we show that a CWG repeat DNA-targeting compound, cyclic pyrrole-imidazole polyamide (CWG-cPIP), suppressed the pathogenesis of coding and noncoding CWG repeat diseases. CWG-cPIP bound to the hairpin form of mismatched CWG DNA, interfering with transcription elongation by RNA polymerase through a preferential activity toward repeat-expanded DNA. We found that CWG-cPIP selectively inhibited pathogenic mRNA transcripts from expanded CWG repeats, reducing CUG RNA foci and polyglutamine accumulation in cells from patients with myotonic dystrophy type 1 (DM1) and Huntington's disease (HD). Treatment with CWG-cPIP ameliorated behavioral deficits in adeno-associated virus-mediated CWG repeat-expressing mice and in a genetic mouse model of HD, without cytotoxicity or off-target effects. Together, we present a candidate compound that targets expanded CWG repeat DNA independently of its genomic location and reduces both pathogenic RNA and protein levels. CWG-cPIP may be used for the treatment of CWG repeat diseases and improvement of clinical outcomes.

Tetraploidy-linked sensitization to CENP-E inhibition in human cells.

Tetraploidy is a hallmark of cancer cells, and tetraploidy-selective cell growth suppression is a potential strategy for targeted cancer therapy. However, how tetraploid cells differ from normal diploids in their sensitivity to anti-proliferative treatments remains largely unknown. In this study, we found that tetraploid cells are significantly more susceptible to inhibitors of a mitotic kinesin (CENP-E) than are diploids. Treatment with a CENP-E inhibitor preferentially diminished the tetraploid cell population in a diploid-tetraploid co-culture at optimum conditions. Live imaging revealed that a tetraploidy-linked increase in unsolvable chromosome misalignment caused substantially longer mitotic delay in tetraploids than in diploids upon moderate CENP-E inhibition. This time gap of mitotic arrest resulted in cohesion fatigue and subsequent cell death, specifically in tetraploids, leading to tetraploidy-selective cell growth suppression. In contrast, the microtubule-stabilizing compound paclitaxel caused tetraploidy-selective suppression through the aggravation of spindle multipolarization. We also found that treatment with a CENP-E inhibitor had superior generality to paclitaxel in its tetraploidy selectivity across a broader spectrum of cell lines. Our results highlight the unique properties of CENP-E inhibitors in tetraploidy-selective suppression and their potential use in the development of tetraploidy-targeting interventions in cancer.

Successful Double-Catheter Coil Embolization of an Iatrogenic Subclavian Artery to Internal Jugular Vein Fistula After Minimally Invasive Cardiac Surgery.

It is essential to establish cardiopulmonary bypass by percutaneous insertion of a large-bore catheter via both the femoral vein and internal jugular vein (IJV) for minimally invasive cardiac surgery (MICS). Complications associated with IJV catheterization during MICS have been reported in the literature; however, vascular injury of the subclavian artery (SCA) is rare. We herein present a rare case in which an iatrogenic arteriovenous fistula (AVF) between the right SCA and IJV after MICS was successfully treated by endovascular coil embolization. A 61-year-old man who had undergone mitral valve repair by MICS 10 months before presentation was referred because of pulsatile cervical bruit and tinnitus. Radiographic examination revealed a right SCA pseudoaneurysm associated with an AVF located between the right common carotid artery and vertebral artery. The AVF was completely occluded with detachable coils using a double-catheter technique to avoid coil migration into the IJV. This technique has been used to treat high-flow or complex AVFs, including pulmonary and renal AVFs. As shown in the present case, it is also useful to treat an iatrogenic AVF between the SCA and IJV.

Microcatheter injection reduces the amount of contrast medium during middle cerebral artery aneurysm embolization in a patient with chronic kidney disease.

We describe a unique technique to reduce the amount of contrast medium by injecting diluted contrast medium from the microcatheter during neurointervention. A patient with severe renal impairment due to polycystic kidney was referred for endovascular surgery for wide-neck middle cerebral artery aneurysm. In order to reduce the amount of contrast medium, contrast medium was injected from the microcatheter placed in the middle cerebral artery during coil embolization; renal function decline was not observed after the procedure. This technique, therefore, reduces the amount of contrast medium and enables one to perform coil embolization safely.

Intracranial myxoid mesenchymal tumor with EWSR1-CREB1 gene fusion: a case report and literature review.

Intracranial myxoid mesenchymal tumors harboring EWSR1 fusions with CREB transcriptional factor gene families were recently described in several case reports and a few case series and this tumor closely resembles the myxoid variant of angiomatoid fibrous histiocytoma. We herein present an intracranial mesenchymal myxoid tumor arising in the third ventricle of a middle-aged woman. The tumor displayed prominent myxoid features consisting of mildly atypical oval to round cells, arranged in reticular and cord-like structures, with starburst-like amianthoid fibers, whereas it lacked pseudoangiomatoid spaces, pseudocapsules and lymphoid cuffing. Immunophenotypically, tumor cells were positive for EMA, desmin, and ALK (focal). EWSR1 and CREB1 rearrangements were identified using FISH assay. The proliferation index was low. It is currently uncertain whether these myxoid tumors represent a variant of angiomatoid fibrous histiocytoma or a novel tumor entity.

5-aminolevulinic acid inhibits oxidative stress and ameliorates autistic-like behaviors in prenatal valproic acid-exposed rats.

Autism spectrum disorders (ASDs) constitute a neurodevelopmental disorder characterized by social deficits, repetitive behaviors, and learning disability. Oxidative stress and mitochondrial dysfunction are associated with ASD brain pathology. Here, we used oxidative stress in prenatal valproic acid (VPA)-exposed rats as an ASD model. After maternal VPA exposure (600 mg/kg, p.o.) on embryonic day (E) 12.5, temporal analyses of oxidative stress in the brain using an anti-4-hydroxy-2-nonenal antibody revealed that oxidative stress was increased in the hippocampus after birth. This was accompanied by aberrant enzymatic activity in the mitochondrial electron transport chain and reduced adenosine triphosphate (ATP) levels in the hippocampus. VPA-exposed rats exhibited impaired spatial reference and object recognition memory alongside impaired social behaviors and repetitive behaviors. ASD-like behaviors including learning and memory were rescued by chronic oral administration of 5-aminolevulinic acid (5-ALA; 30 mg/kg/day) and intranasal administration of oxytocin (OXT; 12 µg/kg/day), a neuropeptide that improves social behavior in ASD patients. 5-ALA but not OXT treatment ameliorated oxidative stress and mitochondrial dysfunction in the hippocampus of VPA-exposed rats. Fewer parvalbumin-positive interneurons were observed in VPA-exposed rats. Both 5-ALA and OXT treatments augmented the number of parvalbumin-positive interneurons. Collectively, our results indicate that oral 5-ALA administration ameliorated oxidative stress and mitochondrial dysfunction, suggesting that 5-ALA administration improves ASD-like neuropathology and behaviors via mechanisms different to those of OXT.

Photoswitchable CENP-E Inhibitor Enabling the Dynamic Control of Chromosome Movement and Mitotic Progression.

Interfering with mitosis is a potential cancer therapy strategy. However, the lack of controllability of antimitotic drugs in cell growth suppression causes severe side effects and limits their clinical utility. Herein, we developed an azobenzene-based photoswitchable inhibitor of CENP-E, a mitotic kinesin required for chromosome transportation. The new inhibitor enabled reversible photoswitching of CENP-E activity with ∼10-fold change in IC50 between cis and trans photoisomerization states both in vitro and in living cells. It also enabled repeatable photoswitching of CENP-E-dependent chromosome congression and hence mitotic progression with UV/vis light illumination cycles. Using this technique, we could specify the exact process of mitotic progression in which CENP-E plays an indispensable role. Our data demonstrate the power of a photochemical approach for highly controllable mitotic interference as well as for discovery of precise molecular functions in dynamic cellular processes.

Enhancement of ATP production ameliorates motor and cognitive impairments in a mouse model of MPTP-induced Parkinson's disease.

Approximately 30-40% of patients with Parkinson's disease (PD) exhibit cognitive impairments. However, there are currently no clinically effective drugs for the treatment of cognitive impairment in patients with PD. Previous studies have suggested that mitochondrial dysfunction such as decreased adenosine triphosphate (ATP) production triggers dopaminergic neurodegeneration in patients with PD and that mitochondria represent a potential target for the development of novel treatments for preventing PD. Therefore, in the present study, we investigated the cognition-enhancing effects of ethyl pyruvate (EP) and 1-(3,4-dimethoxyphenethyl)-4-(3-phenylpropyl) piperazine dihydrochloride (SA4503) in mice with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced Parkinsonism. PD model mice were generated via treatment with MPTP (25 mg/kg, i.p.) once a day for 5 consecutive days. Twenty-four hours after the final injection of MPTP, mice were intraperitoneally injected with EP (25, 50, 100 mg/kg) or SA4503 (1 mg/kg) once a day for 4 weeks. Chronic administration of EP (100 mg/kg i.p.) or SA4503 (1 mg/kg, i.p.) improved both motor deficits and cognitive impairments in MPTP-treated mice. Furthermore, treatment with EP or SA4503 attenuated decreases in the levels of ATP and tyrosine hydroxylase (TH) in the substantia nigra pars compacta (SNpc)/ventral tegmental area (VTA), striatum, and hippocampal CA1 region. Administration of EP or SA4503 protected the dopaminergic neurons from MPTP-induce toxicity and restored the dopamine levels in the striatum. Elevated 4-hydroxy-2-nonenal- (4-HNE-) and nitrotyrosine-reactive protein levels induced by MPTP-treatment were suppressed by EP or SA4503 treatment in the SNpc-VTA, striatum, and hippocampal CA1 region. These observations suggest that EP and SA4503 attenuate cognitive impairments and motor dysfunction in mice with MPTP-induced PD.

Ligand-Directed N-Sulfonyl Pyridone Chemistry for Selective Native Protein Labeling and Imaging in Live Cell.

Advances in biocompatible organic chemistry applicable for endogenous protein modification under live-cell conditions have been longed as these can produce an important tool for the elucidation of a variety of biological phenomena. However, there are still various obstacles to be overcome, such as the limited repertories of the reaction modes, the slow reaction kinetics, and the insufficient specificity for endogenous protein modification. We have recently reported a new type of affinity-based labeling technique termed ligand-directed (LD) chemistry that does not need any genetic manipulation, which shows a sharp contrast with other strategies including peptide/enzyme-tag methods or bioorthogonal chemistry-based methods. Here we describe the general principles of LD chemistry using N-sulfonyl pyridone (SP) as a new reactive group (LDSP chemistry) that allows for endogenous protein sulfonylation with the higher labeling rate and specificity, relative to our previously reported LD chemistry on the surface of and the inside of live cells. The detailed protocols of LDSP chemistry for carbonic anhydrase labeling and imaging in vitro and in living cells are explained.

Substrate selectivity and its mechanistic insight of the photo-responsive non-nucleoside triphosphate for myosin and kinesin.

Linear motor proteins including kinesin and myosin are promising biomaterials for developing nano-devices. Photoswitchable substrates of these biomotors can be used to optically regulate the motility of their associated cytoskeletal filaments in in vitro systems. Here, we describe the discovery of the myosin selective azobenzene-tethered triphosphate. It enables the specific photocontrol over myosin in a reversible mode with the composite motility assay composed of both kinesin and myosin. The mechanistic insight into this myosin selectivity is also explained with the docking simulation study.

Ramelteon Improves Post-traumatic Stress Disorder-Like Behaviors Exhibited by Fatty Acid-Binding Protein 3 Null Mice.

We previously reported that fatty acid-binding protein 3 (FABP3) knockout (Fabp3 -/-) mice exhibit abnormal dopamine-related behaviors such as enhanced dopamine D2 receptor antagonist-induced catalepsy behaviors. Here, we report that Fabp3 null mice exhibit cognitive deficits, hyperlocomotion and impaired fear extinction, and thus show post-traumatic stress disorder (PTSD)-like behaviors. Notably, chronic administration of ramelteon (1.0 mg/kg, p.o.), a melatonin receptor agonist, improved all PTSD-like behaviors tested in Fabp3 -/- mice. Relevant to mechanisms underlying impaired fear extinction, we observed significantly reduced levels of Ca2+/calmodulin-dependent protein kinase II (CaMKII) autophosphorylation without changes in ERK phosphorylation in the anterior cingulate cortex (ACC). Inversely, CaMKII autophosphorylation increased in the basolateral amygdala (BLA) but remained relatively unchanged in hippocampus of Fabp3 -/- mice. Likewise, the number of c-Fos-positive neurons in BLA significantly increased after exposure to contextual fear conditions but remained unchanged in the central nucleus of the amygdala (CeA). Importantly, chronic ramelteon administration (1.0 mg/kg, p.o.) restored abnormal c-Fos expression and CaMKII autophosphorylation in the ACC and BLA of Fabp3 -/- mice. Finally, the melatonin receptor antagonist luzindole (2.5 mg/kg, i.p.) blocked ramelteon-dependent improvements. Taken together, Fabp3 -/- mice show PTSD-like behaviors, and ramelteon is a likely attractive candidate for PTSD therapy.

Combined l-citrulline and glutathione administration prevents neuronal cell death following transient brain ischemia.

We previously reported that oral l-citrulline (l-Cit) administration antagonizes neuronal cell death in hippocampus following transient brain ischemia and that oral glutathione (GSH) administration prevents neuronal death through antioxidant activity. Here, we tested potential synergy of combined l-Cit and GSH administration in protection against neuronal death following cerebral ischemia. One day after a 20-min bilateral common carotid artery occlusion (BCCAO), mice were orally administered l-Cit or GSH alone (at 40 or 100mg/kgp.o.) or both (at 40mg/kgp.o. each) daily for 10days. The combination, but not l-Cit or GSH alone at 40mg/kgp.o., significantly prevented neuronal death in the hippocampal CA1 region in BCCAO mice. Consistently, combined l-Cit and GSH administration improved memory-related behavioral deficits observed in BCCAO mice. Combination treatment also significantly rescued reduced endothelial nitric oxide synthase (eNOS) protein levels and antagonized eNOS S-glutathionylation seen following BCCAO ischemia. Recovery of eNOS activity was confirmed by in vivo NO production in hippocampus of BCCAO mice. Taken together, combined administration of l-Cit with GSH rescues eNOS function, thereby inhibiting delayed neuronal death in hippocampus.

Structure-property relationships of photoresponsive inhibitors of the kinesin motor.

Recently we demonstrated the photoregulation of the activity of kinesin-1 using an azobenzene-tethered peptide (azo-peptide: Azo-Ile-Pro-Lys-Ala-Ile-Gln-Ala-Ser-His-Gly-Arg-OH). To understand the mechanism behind this photoswitchable inhibition, here we studied the structure-property relationships of a range of azo-peptides through systematic variations in the structures of the peptide and azobenzene units. The vital peptide sequence for kinesin inhibition-mediated through electrostatic, hydrophobic and C-Hπ interactions-was the same as that for the self-inhibition of kinesin. We also identified substituents on the azobenzene capable of enhancing the photoswitchability of inhibition. As a result, we developed a new inhibitor featuring a relatively short peptide unit (-Arg-Ile-Pro-Lys-Ala-Ile-Arg-OH) and an azobenzene unit bearing a para-OMe group. In the trans form of its azobenzene unit, this finely tuned inhibitor stopped the kinesin-driven gliding motility of microtubules completely at a relatively low concentration, yet allowed gliding motility with a relatively high velocity in the cis form obtained after UV irradiation.

Specific detection and imaging of enzyme activity by signal-amplifiable self-assembling (19)F MRI probes.

Specific turn-on detection of enzyme activities is of fundamental importance in drug discovery research, as well as medical diagnostics. Although magnetic resonance imaging (MRI) is one of the most powerful techniques for noninvasive visualization of enzyme activity, both in vivo and ex vivo, promising strategies for imaging specific enzymes with high contrast have been very limited to date. We report herein a novel signal-amplifiable self-assembling (19) F NMR/MRI probe for turn-on detection and imaging of specific enzymatic activity. In NMR spectroscopy, these designed probes are "silent" when aggregated, but exhibit a disassembly driven turn-on signal change upon cleavage of the substrate part by the catalytic enzyme. Using these (19) F probes, nanomolar levels of two different target enzymes, nitroreductase (NTR) and matrix metalloproteinase (MMP), could be detected and visualized by (19) F NMR spectroscopy and MRI. Furthermore, we have succeeded in imaging the activity of endogenously secreted MMP in cultured media of tumor cells by (19) F MRI, depending on the cell lines and the cellular conditions. These results clearly demonstrate that our turn-on (19) F probes may serve as a screening platform for the activity of MMPs.