Positive and Negative Impacts of Interfacial Hydrogen Bonds on Photocatalytic Hydrogen Evolution.

Understanding the behavior of water molecules at solid-liquid interfaces is crucial for various applications such as photocatalytic water splitting, a key technology for sustainable fuel production and chemical transformations. Despite extensive studies conducted in the past, the impact of the microscopic structure of interfacial water molecules on photocatalytic reactivity has not been directly examined. In this study, using real-time mass spectrometry and Fourier-transform infrared spectroscopy, we demonstrated the crucial role of hydrogen bond (H-bond) networks on the photocatalytic hydrogen evolution in thickness-controlled water adsorption layers on various TiO2 photocatalysts. Under controlled water vapor environments with relative humidity (RH) below 70%, we observed a monotonic increase in the H2 formation rate with increasing RH, indicating that reactive water molecules were present not only in the first adsorbed layer but also in several overlying layers. In contrast, at RH > 70%, when more than three water layers covered the catalyst surface, the H2 formation rate turned to decrease dramatically because of the structural rearrangement and hardening of the interfacial H-bond network induced during further water adsorption. This unique many-body effect of interfacial water was consistently observed for various TiO2 particles with different crystalline structures, including brookite, anatase, and a mixture of anatase and rutile. Our results demonstrated that depositing several water layers in a water vapor environment with RH ∼ 70% is optimal for photocatalytic hydrogen evolution rather than liquid-phase reaction conditions in aqueous solutions. This study provides molecular-level insights into designing interfacial water conditions to enhance photocatalytic performance.

Beyond Reduction Cocatalysts: Critical Role of Metal Cocatalysts in Photocatalytic Oxidation of Methane with Water.

Environmentally sustainable and selective conversion of methane to valuable chemicals under ambient conditions is pivotal for the development of next-generation photocatalytic technology. However, due to the lack of microscopic knowledge about non-thermal methane conversion, controlling and modulating photocatalytic oxidation processes driven by photogenerated holes remain a challenge. Here, we report novel function of metal cocatalysts to accept photogenerated holes and dominate selectivity of methane oxidation, which is clearly beyond the conventional concept in photocatalysis that the metal cocatalysts loaded on the surfaces of semiconductor photocatalysts mostly capture photogenerated electrons and dominate reduction reactions exclusively. The novel photocatalytic role of metal cocatalysts was verified by operando molecular spectroscopy combined with real-time mass spectrometry for metal-loaded Ga2 O3 model photocatalysts under methane and water vapor at ambient temperature and pressure. Our concept of metal cocatalysts that work as active sites for both photocatalytic oxidation and reduction provides a new understanding of photocatalysis and a solid basis for controlling non-thermal redox reactions by metal-cocatalyst engineering.

Role of Microelectrode Recording in Deep Brain Stimulation of the Pedunculopontine Nucleus: A Physiological Study of Two Cases.

BACKGROUND: Deep brain stimulation (DBS) of the pedunculopontine nucleus (PPN) has been reported to improve gait disturbances in Parkinson's disease (PD); however, there are controversies on the radiological and electrophysiological techniques for intraoperative and postoperative confirmation of the target and determination of optimal stimulation parameters. OBJECTIVES: We investigated the correlation between the location of the estimated PPN (ePPN) and neuronal activity collected during intraoperative electrophysiological mapping to evaluate the role of microelectrode recording (MER) in identifying the effective stimulation site in two PD patients. MATERIALS AND METHODS: Bilateral PPN DBS was performed in two patients who had suffered from levodopa refractory gait disturbance. They had been implanted previously with DBS in the internal globus pallidus and the subthalamic nucleus, respectively. The PPN was determined on MRI and identified by intraoperative MER. Neuronal activity recorded was analyzed for mean discharge rate, bursting, and oscillatory activity. The effects were assessed by clinical ratings for motor signs before and after surgery. RESULTS: The PPN location was detected by MER. Groups of neurons characterized by tonic discharges were found 9-10 mm below the thalamus. The mean discharge rate in the ePPN was 19.1 ± 15.1 Hz, and 33% of the neurons of the ePPN responded with increased discharge rate during passive manipulation of the limbs and orofacial structures. PPN DBS with bipolar stimulation at a frequency range 10-30 Hz improved gait disturbances in both patients. Although PPN DBS provided therapeutic effects post-surgery in both cases, the effects waned after a year in case 1 and three years in case 2. CONCLUSIONS: Estimation of stimulation site within the PPN is possible by combining physiological guidance using MER and MRI findings. The PPN is a potential target for gait disturbances, although the efficacy of PPN DBS may depend on the location of the electrode and the stimulation parameters.

Anti-Mycobacterial N-(2-Arylethyl)quinolin-3-amines Inspired by Marine Sponge-Derived Alkaloid.

The synthesis and evaluation of simplified analogs of marine sponge-derived alkaloid 3-(phenethylamino)demethyl(oxy)aaptamine were performed to develop novel anti-mycobacterial substances. Ring truncation of the tricyclic benzo[de][1,6]-naphthyridine skeleton effectively weakened the cytotoxicity of the natural product, and the resulting AC-ring analog exhibited good anti-mycobacterial activity. A structure-activity relationship (SAR) study, synthesizing and evaluating some analogs, demonstrated the specificity and importance of the N-(2-arylethyl)quinolin-3-amine skeleton as a promising scaffold for anti-mycobacterial lead compounds.

Theoretical Study on Redox Potential Control of Iron-Sulfur Cluster by Hydrogen Bonds: A Possibility of Redox Potential Programming.

The effect of hydrogen bonds around the active site of Anabaena [2Fe-2S] ferredoxin (Fd) on a vertical ionization potential of the reduced state (IP(red)) is examined based on the density functional theory (DFT) calculations. The results indicate that a single hydrogen bond increases the relative stability of the reduced state, and shifts IP(red) to a reductive side by 0.31-0.33 eV, regardless of the attached sulfur atoms. In addition, the IP(red) value can be changed by the number of hydrogen bonds around the active site. The results also suggest that the redox potential of [2Fe-2S] Fd is controlled by the number of hydrogen bonds because IP(red) is considered to be a major factor in the redox potential. Furthermore, there is a possibility that the redox potentials of artificial iron-sulfur clusters can be finely controlled by the number of the hydrogen bonds attached to the sulfur atoms of the cluster.

Long-Term Suppression of Disabling Tremor by Thalamic Stimulation in a Patient with Spinocerebellar Ataxia Type 2.

The beneficial effect of thalamic deep brain stimulation (DBS) on action tremor has been reported in a few cases of spinocerebellar ataxia (SCA); however, several factors should be taken into account regarding the indication for DBS in advanced cases. We performed DBS of the ventral intermediate nucleus (Vim) of the thalamus for treatment of coarse action tremor in a patient with SCA2 (spinocerebellar ataxia type 2) in the wheelchair-bound stage. Although improvement of the tremor of the proximal part was incomplete, the patient regained substantial parts of daily functioning. The effect lasted for more than 6 years, and the suppression of tremor significantly contributed to maintaining the level of the patient's expression into the bedridden stage. Vim DBS can be a treatment option for tremor in SCA patients, even in the advanced stage, as long as the tremor is depriving the patient of behavioral expression. As residual proximal tremor may hamper functional recovery, DBS of other targets or multi-targets should be further explored to attain a better outcome.

Clinico-Radiological Characteristics and Pathological Diagnosis of Cerebral Amyloid Angiopathy-Related Intracerebral Hemorrhage.

OBJECTIVE: We aim to clarify the clinico-radiological characteristics of cerebral amyloid angiopathy-related intracerebral hemorrhage and to investigate the efficacy of pathological diagnosis using biopsy specimens. METHOD: We retrospectively reviewed 253 consecutive patients with cortico-subcortical hemorrhage who had been admitted to Aizawa Hospital between January 2006 and July 2013. We had performed craniotomy and hematoma evacuation in 48 patients, as well as biopsy of the evacuated hematoma, cerebral parenchyma adjacent to the hematoma, or both, and they were classified according to the histological results (positive or negative for vascular amyloid deposition) and to the Boston criteria. We compared the clinico-radiological characteristics of cerebral amyloid angiopathy-related intracerebral hemorrhage. We also investigated the detection rate of cerebral amyloid angiopathy with respect to the origins of the specimens. RESULTS: Pathological examination revealed that 22 subjects were positive for vascular amyloid. The number of the cerebral microbleeds located in the deep or infratentorial region was significantly larger in the negative group than in the positive group (P <.05). There was no significant difference in the distribution of lobar cerebral microbleeds and in the prevalence of hypertension. In the probable cerebral amyloid angiopathy-related intracerebral hemorrhage patients, the probability of having vascular amyloid detected by biopsy of both hematoma and parenchyma was 100%. Rebleeding in the postoperative periods was observed in 2 cases (9.1%) of the positive group. CONCLUSIONS: Our results demonstrate the importance and safety of biopsy simultaneously performed with hematoma evacuation. Deep or infratentorial microbleeds are less correlated with cerebral amyloid angiopathy-related intracerebral hemorrhage than with noncerebral amyloid angiopathy-related intracerebral hemorrhage.

Fabrication of Waterborne Silicone-Modified Polyurethane Nanofibers for Nonfluorine Elastic Waterproof and Breathable Membranes.

Waterproof and breathable membranes have a huge market demand in areas, such as textiles and medical protection. However, existing fluorinated nanofibrous membranes, while possessing good waterproof and breathable properties, pose health and environmental hazards. Consequently, fabricating fluorine-free, eco-friendly waterborne membranes by integrating outstanding waterproofing, breathability, and robust mechanical performance remains a significant challenge. Herein, we successfully prepared waterborne silicone-modified polyurethane nanofibrous membranes with excellent elasticity, waterproofing, and breathability properties through waterborne electrospinning, using a small quantity of poly(ethylene oxide) as a template polymer and in situ doping of the poly(carbodiimide) crosslinking agent, followed by a simple hot-pressing treatment. The silicone imparted the nanofibrous membrane with high hydrophobicity, and the crosslinking agent enabled its stable porous structure. The hot-pressing treatment (120 °C) further reduced the pore size and improved the water resistance. This environmentally friendly nanofibrous membrane showed a high elongation at break of 428%, an ultra-high elasticity of 67.5% (160 cycles under 400% tensile strain), an air transmission of 13.2 mm s-1, a water vapor transmission rate of 5476 g m-2 d-1, a hydrostatic pressure of 51.5 kPa, and a static water contact angle of 137.9°. The successful fabrication of these environmentally friendly, highly elastic membranes provides an important reference for applications in healthcare, protective textiles, and water purification.

Preparation of Waterborne Silicone-Modified Polyurethane Nanofibers and the Effect of Crosslinking Agents on Physical Properties.

Silicone-modified polyurethane (PUSX) refers to the introduction of a silicone short chain into the polyurethane chain to make it have the dual properties of silicone and polyurethane (PU). It can be used in many fields, such as coatings, films, molding products, adhesives, and so on. The use of organic solvents to achieve the fiberization of silicone-modified polyurethane has been reported. However, it is challenging to achieve the fiberization of silicone-modified polyurethane based on an environmentally friendly water solvent. Herein, we report a simple and powerful strategy to fabricate environmentally friendly waterborne silicone-modified polyurethane nanofiber membranes through the addition of polyethylene glycol (PEG) with different molecular weights using electrospinning technology and in situ doping with three crosslinking agents with different functional groups (a polyoxazoline crosslinking agent, a polycarbodiimide crosslinking agent, and a polyisocyanate crosslinking agent) combined with various heating treatment conditions. The influence of PEG molecular weight on fiber formation was explored. The morphology, structure, water resistance, and mechanical properties were analyzed regarding the effect of the introduction of silicone into PU. The effects of the type and content of crosslinking agent on the morphology and physical properties of PUSX nanofiber membranes are discussed. These results show that the introduction of silicone can improve the water resistance and high temperature resistance of waterborne PU, and the addition of a crosslinking agent can further improve the water resistance of the sample, so that the sample can maintain good morphology after immersion. Crosslinking agents with different functional groups had different effects on the mechanical properties of PUSX nanofiber membranes due to different reactions. Among them, the oxazoline crosslinking agent had a significant effect on improving tensile strength, while the isocyanate crosslinking agent had a significant effect on improving the elongation at break. The PUSX nanofiber membrane prepared in this work did not use organic solvents that were harmful to humans and the environment, and it can be used in outdoor textiles, oil-water separation, medical health, and other fields.

Critical impacts of interfacial water on C-H activation in photocatalytic methane conversion.

On-site and on-demand photocatalytic methane conversion under ambient conditions is one of the urgent global challenges for the sustainable use of ubiquitous methane resources. However, the lack of microscopic knowledge on its reaction mechanism prevents the development of engineering strategies for methane photocatalysis. Combining real-time mass spectrometry and operando infrared absorption spectroscopy with ab initio molecular dynamics simulations, here we report key molecular-level insights into photocatalytic green utilization of methane. Activation of the robust C-H bond of methane is hardly induced by the direct interaction with photogenerated holes trapped at the surface of photocatalyst; instead, the C-H activation is significantly promoted by the photoactivated interfacial water species. The interfacial water hydrates and properly stabilizes hydrocarbon radical intermediates, thereby suppressing their overstabilization. Owing to these water-assisted effects, the photocatalytic conversion rates of methane under wet conditions are dramatically improved by typically more than 30 times at ambient temperatures (~300 K) and pressures (~1 atm) in comparison to those under dry conditions. This study sheds new light on the role of interfacial water and provides a firm basis for design strategies for non-thermal heterogeneous catalysis of methane under ambient conditions.

Acute cerebral microbleeds at the edge of lacunar strokes: cause or result.

We investigated the pathogenic relationship between cerebral microbleeds and lacunar strokes. Two cases of lacunar strokes in the region of the basal ganglia, a 72-year-old man and a 67-year-old man, were studied; both cases showed cerebral microbleeds in the stroke areas. The cerebral microbleeds were surrounded by oedema, and the oedema faded out over time, suggesting the cerebral microbleeds had developed acutely. The cerebral microbleeds were located at the ventrolateral edge of the lacunar infarctions, and the locations appeared to be at or near the sites of occlusion of the lenticulostriatal branches. Although a cerebral microbleed and a lacunar infarction may be two unrelated events on juxtapositioned vessels, or a cerebral microbleed may be haemorrhagic conversion of an infarction, a cerebral microbleed could cause an occlusion of the arterial branch, leading to lacunar infarction of its supplying territories.

Upward gaze palsy and convergence insufficiency as a rare presentation of primary intraventricular haemorrhage.

A primary intraventricular haemorrhage (PIVH) usually presents with non-localised neurological symptoms since the haematoma is limited to the ventricles. However, it is sometimes associated with focal neurological signs, whose pathophysiologies are not confirmed. Here, we report on a case of PIVH who showed rare manifestations in the acute stage: upward gaze palsy and convergence insufficiency. The CT and MRI showed intraventricular haematoma without evidence of parenchymal haemorrhage, local mass effect around midbrain or hydrocephalus. There had been bilateral papilloedema, and it resolved along with improvement of the ophthalmic symptoms, suggesting a possible causal relation to increased intracranial pressure. The ophthalmic abnormalities suggested injury of the rostral part of the midbrain, especially the region around the dorsal midbrain tectum. It should be known that PIVH is one of the causes of acutely developing upward gaze palsy and convergence insufficiency.

Physical Properties and In Vitro Biocompatible Evaluation of Silicone-Modified Polyurethane Nanofibers and Films.

In this study, the physical properties and the biocompatibility of electrospun silicone-modified polyurethane (PUSX) nanofibers were discussed and compared with PUSX films. To investigate the effects of different structures on the physical properties, tensile strength, elongation at break, Young's modulus, water retention, water contact angle (WCA) and thermal conductivity measurements were performed. To prove the in vitro biocompatibility of the materials, cell adhesion, cell proliferation, and cytotoxicity were studied by NIH3T3 mouse embryonic fibroblasts cells following by lactate dehydrogenase (LDH) analysis. As a conclusion, the mechanical properties, water retention, and WCA were proven to be able to be controlled and improved by adjusting the structure of PUSX. A higher hydrophobicity and lower thermal conductivity were found in PUSX nanofibers compared with polyurethane (PU) nanofibers and films. An in vitro biocompatibility evaluation shows that the cell proliferation can be performed on both PUSX nanofibers and films. However, within a short period, cells prefer to attach and entangle on PUSX nanofibers rather than PUSX films. PUSX nanofibers were proven to be a nontoxic alternative for PU nano-membranes or films in the biomedical field, because of the controllable physical properties and the biocompatibility.

Accurate Detection of Tumor Infiltration by 11C-Methionine Positron Emission Tomography in a Patient with Central Nervous System Intravascular Lymphoma: A Case Report.

Intravascular lymphoma (IVL) is a rare and clinically devastating subtype of extranodal diffuse large B-cell lymphoma with a distinct presentation. Diagnostic difficulty derives from marked variability in clinical presentations and nonspecific laboratory and radiological findings, especially when central nervous system (CNS) symptoms are the only manifestation. Establishing the diagnosis premortem thus remains a major challenge. We describe a 70-year-old male with CNS IVL. He presented with acute onset of neurocognitive impairments. Diffusion-weighted magnetic resonance imaging (MRI) showed multiple high-intensity areas suggesting occlusive cerebrovascular disease due to emboli, but extensive investigations detected no embolic sources. Intracranial neoplasm was included in a differential diagnosis based on elevated serum lactate dehydrogenase and interleukin 2 receptor levels. Gadolinium-enhanced MRI or 18-fluorodeoxyglucose positron emission tomography (PET) failed to demonstrate specific findings leading to a definite diagnosis, while 11C-methionine PET (MET-PET) distinctively demonstrated an area of focally increased MET uptake in the frontal cortex, suggesting the extent of tumor infiltration. Stereotactic biopsy was conducted under MET-PET imaging guidance and immunohistological examinations confirmed the proliferation and aggregation of CD20-positive lymphoma cells within the lumina of small blood vessels. The findings of the present case first suggest that MET-PET may provide important information on the diagnosis of CNS IVL and on the selection of the optimal site for brain biopsy. Further investigation is necessary to clarify whether positive findings on MET-PET are truly specific and pathognomonic for CNS IVL.

Dysphagia Causes Symptom Fluctuations after Oral L-DOPA Treatment in a Patient with Parkinson Disease.

OBJECTIVE: The causes of "delayed-on" and "no-on" phenomena in Parkinson disease (PD) are thought to have some impact on the progress of L-DOPA from the time of ingestion until it reaches the brain and is converted to dopamine. Dysphagia can cause fluctuating symptom expression in L-DOPA therapy for PD. CASE DESCRIPTION: A 69-year-old man with PD presented with "delayed-on" and "no-on" phenomena. The patient developed a gait disorder at age 60 years, and he began coughing on his food during breakfast at age 64 years. Even though he was independent in daily life, he could not eat because of dysphagia in an "off" state. Videofluoroscopic examination of swallowing in an "off" state revealed bradykinesia of the tongue and the retention of tablets in the epiglottic vallecula. We trained him to keep his tongue in strong contact with the upper incisors before swallowing. After rehabilitation of dysphagia, the frequency of "delayed-on" and "no-on" phenomena decreased, and his peak L-DOPA plasma concentration was elevated. Additionally, transdermal rotigotine (RTG) was initiated at a maintenance dose of 9.0 mg. The patient reported improvement in swallowing, and the frequency of "no-on" phenomena decreased. CONCLUSION: In PD patients, the "no-on" phenomenon can be caused by posterior contractile dysfunction of the tongue, and it can be improved with training of the tongue and transdermal RTG administration.

Electrospinning of Block and Graft Type Silicone Modified Polyurethane Nanofibers.

Silicone modified polyurethane (PUSX) has attracted interest as a useful material by various properties, which are combined with silicone and polyurethane. In this paper, we tried to optimize the electrospinning process of silicone modified polyurethane (PUSX) nanofibers on a lab scale device and a multinozzle pilot scale set-up to investigate the potential and limitations of preparing PUSX nanofibrous sheets using different equipment. The morphology and diameter of the obtained fibers were studied via scanning electron microscopy (SEM). Attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR) was also carried out to analyze the chemical structure of PUSX nanofibers. As a result, we successfully figured out the optimal parameters of PUSX electrospinning process and demonstrated the great potential of the process for mass production of PUSX nanofibrous sheets from solutions.

Clinical characteristics and etiology of transient myoclonic state in the elderly.

OBJECTIVES: To clarify clinical picture of transient myoclonic state in elderly patients. METHODS: The Aizawa Hospital database was searched to identify all patients with transient myoclonic state with or without asterixis between April 2006 and June 2013. Medical records, brain images and laboratory data including electroencephalograms and electromyograms were reviewed. RESULTS: We found 26 patients: 10 women and 16 men, and their ages ranged from 56 to 96 years (79.7 ± 9.9 years, mean ± standard deviation). The affected sites of the myoclonic jerks were predominantly the lower face, neck and upper extremities. The myoclonus appeared at conscious resting condition, slightly exaggerated by posturing or action. Asterixis was observed in eight patients. Single myoclonic bursts were 1.70 ± 0.94 s long. The interval of myoclonic bursts was 4.47 ± 2.44 s. Single myoclonic bursts were composed of 9.5 ± 2.5 Hz myoclonic contractions, and single myoclonic contractions were 44.4 ± 12.3 ms in duration. Most of the patients suffered from chronic diseases, but they were basically independent in activity of daily living. Oral administration of clonazepam was effective. CONCLUSIONS: Transient myoclonic state has relatively stereotyped features. The pathophysiology may include some metabolic abnormality on a background of age-related arteriosclerotic changes. Its prognosis is benign, and prompt oral administration of clonazepam abolishes it. Further investigations will be needed to clarify its cause and pathophysiology.

Burst suppression electroencephalogram with mushroom poisoning, Amanita pantherina.

We report on a patient with Amanita pantherina poisoning who showed a burst suppression pattern on electroencephalography during a comatose state. The patient recovered without sequelae a week after ingestion. Burst suppression pattern is defined as alternating bursts and periods of electrical silence, and it is associated with comatose states of various causes. The major toxins contained in A. pantherina are ibotenic acid, an excitatory amino acid at the glutamate receptors, and muscimol, an agonist of the gamma-aminobutyric acid receptors. Alteration of the synaptic transmission in the central nervous system by these toxins may lead to a burst suppression pattern.

Treatment of myasthenia gravis with dropped head: a report of 2 cases and review of the literature.

We report two patients with myasthenia gravis (MG) who showed dropped head as an early myasthenic manifestation. They had elevated anti-acetylcholine receptor antibody and showed improvement of the symptoms after intravenous injection of edorophonium chloride. One patient had thymoma and developed myasthenic crisis two weeks after thymectomy. The patient recovered from the crisis after a combination of immunoadsorption plasmapheresis (IAPP) and initiation of steroid and tacrolimus. The other patient without thymoma initiated treatment with steroid, tacrolimus and IAPP and showed complete recovery one month later. Dropped head in MG can recover well with immunosuppression therapy using steroid, and IAPP is helpful in getting a rapid improvement of dropped head as well as recovery from myasthenic crisis. When we consider treatment for MG with dropped head, we should take into account that MG of this type can develop myasthenic crisis and use the same treatment strategy as that for generalized MG.

Acute isolated bilateral mydriasis: case reports and review of the literature.

Isolated bilateral internal ophthalmoplegia is a rare and problematic condition affecting activities of daily living. Herein, we describe the cases of 2 patients with postinfectious isolated bilateral internal ophthalmoplegia, i.e., mydriasis without external ophthalmoplegia. One patient demonstrated no other neurological symptom, while the other patient showed mild gait ataxia. Magnetic resonance imaging revealed no abnormal findings in the brain or brainstem. Light-near dissociation of the pupils was not recognized in either patient, and supersensitivity to dilute pilocarpine was observed in 1 of the 2 patients. An increased titer of the anti-GQ1b IgG antibody was noted in 1 patient. A review of the literature revealed five similar cases; the symptomatic characteristics, ratio of positive anti-GQ1b IgG antibody, and effective treatment are discussed.