Publications by authors named "Kiyotaka Sato"

Compound chocolates made of lauric-acid-based cocoa butter substitute (CBS) and cocoa butter (CB) often exhibit serious fat blooms caused by phase separation and polymorphic transformation of CB and CBS triacylglycerols. Herein, we found that the fat bloom of CBS-based chocolates could be completely inhibited by adding fat containing 1,3-dioleoyl-2-stearoyl-triacylglycerol (OSO) to CBS/CB blends. Unlike the CBS/CB chocolates that presented fat blooms within 3 wk under isothermal storage at 15, 20, and 25°C and 15 wk under thermal thawing storage at 15-25°C , no fat blooms appeared in the CBS/CB/OSO compound chocolates under any storage condition up to 6 months.

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The crystallization behavior of the metastable α form of triacylglycerols (TAGs) plays a critical role as a precursor for the crystallization of more stable β' and β forms for various applications in food and pharmaceutical products. However, precise analysis of the crystallization kinetics of α has not been performed, likely due to its rapid and complex behavior. This paper presents the observation results of the initial stages of the isothermal crystallization kinetics of α forms of 1,3-dipalmitoyl-2-oleoyl-glycerol (POP), 1,2-dipalmitoyl-3-oleoyl--glycerol (-PPO), and molecular compound (MC) crystals of a POP/-PPO (1/1) mixture (MCPOP/PPO) using synchrotron radiation time-resolved X-ray diffraction and polarized optical microscopy.

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This paper reports an experimental study of the formation and properties of dark chocolate prepared using novel CB alternative fats (CBAs): symmetric (OSO) and asymmetric (SSO) mixed-acid triacylglycerols (TAGs), in which Sat and O represent saturated fatty acids (stearic:S + palmitic:P) and oleic acid moieties, respectively. It was found that the ternary fat mixtures of CB/SSO/OSO with a ratio of CB/(SSO + OSO) of 1:1 formed the most stable β-form of the double chain length (DCL) structure (β-2), which revealed sufficient hardness and sharp melting profiles around body temperature without tempering processes. Fat bloom formation was not observed in dark chocolate with CBAs at ratios of CB/SSO/OSO of 50/20/30-50/0/50 during the one-year storage test at temperatures between 15 °C and 30 °C.

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Most natural lipids contain a complex mixture of individual triacylglycerols (TAGs). An in-depth knowledge of the mixing behavior of TAGs is necessary for the rational design and engineering of food materials. The binary phase diagram of TAGs is a simplified model that can be explored to help foster an understanding of the phase behavior of complex fats and oils.

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We systematically examined the phase behavior of binary mixtures of mixed-acid triacylglycerols (TAGs) containing palmitic and oleic acid moieties 1,3-dioleoyl-2-palmitoyl-glycerol (OPO), 1,2-dipalmitoyl-3-oleoyl-rac-glycerol (PPO), and 1,2-dioleoyl-3-palmitoyl-rac-glycerol (OOP), which are widely present in natural fats and are employed in the food, pharmaceutical, and cosmetic industries. Differential scanning calorimetry and X-ray diffraction methods were applied to observe the mixing behavior of PPO/OPO, OOP/OPO, and PPO/OOP under metastable and stable conditions. The results led to three conclusions: (1) Eutectic behavior was observed in PPO/OPO.

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We examined the promotional effects of additives on fat crystallization, such as inorganic (talc, carbon nanotube (CNT), and graphite) and organic (theobromine, ellagic acid dihydrate (EAD), and terephthalic acid) materials. The triacylglycerols (TAGs) of trilauroylglycerol (LLL), trimyristoylglycerol (MMM), and tripalmitoylglycerol (PPP) were employed as the fats. The additives (1 wt%) were added to the molten TAGs, and then the mixtures were cooled at a rate of 1°C/min followed by heating at a rate of 5°C/min.

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We retrospectively analyzed 15 years experience of awake surgeries for neuroepithelial tumors in Tohoku University. Awake surgeries mostly for language mapping were performed for 42 of 681 newly diagnosed cases (6.2%) and 59 of 985 surgeries including for recurrence (6.

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This study examined the influence of different thermal treatments on the crystallization and transformation of trioleoyl glycerol (OOO) and 1,2-dioleoyl-3-rac-linoleoyl glycerol (OOL). Two triacylglycerol (TAG) samples were cooled at 0.5-15 °C·min(-1) and heated at 2 and 15 °C·min(-1).

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Background And Importance: Bridging veins arising from the frontal base (frontobasal bridging veins, FBBVs) can pose obstacles when performing clipping of anterior communicating artery (ACoA) aneurysms via the pterional approach. Although FBBVs can in general be sacrificed without critical complications to achieve an adequate retraction of the frontal lobe, neurosurgeons sometimes encounter postoperative venous infarction or contusion of the retracted frontal lobe, which may be accounted for by the damage to the venous drainage system. Thus, preservation of intracranial veins is desirable to prevent postoperative venous complications, especially when they are prominent.

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It has been reported that K-ATP channel openers have a cardioprotective effect in acute ischemia as a pharmacological preconditioning effect. In the present study, the chronic effects of clinical K-ATP channel openers, ie, nicorandil (Nic) and mexiletine (Mex), on cardiac function were evaluated in a rat model of experimental autoimmune myocarditis (EAM). Nicorandil (3 or 10 mg/kg/day) or Mex (10 or 25 mg/kg/day) was administered to the EAM rats, and the effects were compared with those in untreated EAM rats (control EAM) and sham rats without EAM on day 21 (acute phase) or day 60 (chronic phase).

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Using macrobeam and microbeam techniques, we performed synchrotron radiation X-ray diffraction (SR-XRD) analyses of fat crystallization in water-in-oil (W/O) emulsion, in combination with DSC and polarized optical microscopic observation. Particular focus was on the crystallization of the fats around water droplets in the W/O emulsion systems using food emulsifiers of polyglycerol polyricinoleate (PGPR) alone (PGPR emulsion), and PGPR and monobehenoylglycerol (MB) (PGPR+MB emulsion). We obtained the following results: (1) macrobeam SR-XRD confirmed that adding MB promoted fat crystallization during cooling, (2) microbeam SR-XRD indicated that the lamellar planes of fat crystals near the water and oil interfaces are arranged almost parallel to the interface planes in both PGPR emulsion and PGPR+MB emulsion, and (3) adding MB resulted in the formation of tiny fat crystals because it promoted crystallization, which occurred both in the bulk oil phase and at the W/O interfaces.

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Rice bran wax (RBX) obtained during rice bran oil purification can form organogels in edible oils. The kinetics of crystallization and the viscous properties of RBX organogels were studied using differential scanning calorimetry (DSC), viscosity changes with varying temperature, hardness measurements by penetrometry, and synchrotron radiation X-ray diffraction (SR-XRD). The organogels were prepared by RBX in concentrations of 1%, 3%, 6%, and 10% on a weight basis in salad oil, olive oil, and camellia oil.

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Owing to public concern regarding the adverse health effects of trans fatty acids, an alternative technology to trans fats has recently become an important issue. The interesterification of fully hydrogenated vegetable oil and liquid oil blends is one of the most versatile options. This paper reports a physical analysis of high-melting fat (HMF) prepared through the interesterification of fully hydrogenated soybean oil and regular soybean oil, and through fractionation.

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The phase behavior of a binary mixture of triacylglycerol (TAG), POP (1,3-dipalmitoyl-2-oleoyl-sn-glycerol), and OPO (1,3-dioleoyl-2-palmitoyl-sn-glycerol) in an organic solvent, n-dodecane, was examined by DSC and synchrotron radiation X-ray diffraction (SR-XRD). In our previous study on POP-OPO mixtures in neat liquid, the formation of molecular compound (MC) crystals of POP/OPO = 50/50 was observed (Minato et al. J.

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Background: In surgeries for epilepsy, electrocorticography (ECoG) enables tailored resection of the epileptogenic brain and pharmacological stimulation should be employed in surgeries under general anesthesia. To identify the efficacy of continuous remifentanil in surgeries for epilepsy, ECoG findings with remifentanil and those with sevoflurane were compared.

Methods: Sixteen patients with intractable epilepsy were included with institutional ethics committee approval and informed consent.

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Object: Integration of neuronavigation into brain tumor surgery can improve the accuracy and precision of resection, but most neuronavigation systems require rigid pin fixation of the patient's head throughout the operation. We describe use of a noninvasive skull reference tool, which can replace rigid pin fixation in awake craniotomy and pediatric surgery, when standard pin fixation cannot be used.

Methods And Results: The skull reference tool (BrainLAB, Munich, Germany) is directly attached to the outer skull with a small self-tapping screw.

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The negative motor area and anterior and posterior language areas were localized by intraoperative electrical cortical stimulation under the awake condition to evaluate the clinical significance of these areas. Thirty-seven awake craniotomies with language mapping were performed in 36 patients with brain tumors. The negative motor area was determined in 17 cases, and the anterior and posterior language areas were found in 12 and 6 cases, respectively.

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Purpose: Intensive hypotension is an important technique in neurosurgical perioperative management. However, it could decrease urine volume, and induce fluid retention resulting in cardiac failure. We evaluated the efficacy of human atrial natriuretic peptide (hANP) on diuresis in a hypotensive condition.

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Background: Early detection of complications after craniotomies are important and remifentanil may be beneficial for that purpose because of the short and constant context-sensitive half time. To examine the efficacy of remifentanil in neuroanesthesia, we investigated hemodynamic properities and recovery from anesthsia in craniotomies.

Methods: Fifty patients undergoing scheduled neurosurgical procedures were included.

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To avoid the neurological deficits after neurosurgical procedures, awake craniotomy applying intraoperative awake functional brain mapping has been employed. Anesthesia for awake craniotomy requires particular attention to airway management, control of seizures and measures for decreasing the anxiety of the patients. We investigated the current status of anesthetic management for awake craniotomy in Japan to establish a standard procedure for safe anesthesia.

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Background: In carotid endarterectomy (CEA), it is essential to maintain the systemic blood pressure (BP) and cerebral perfusion pressure, especially during cross clamping, and vasopressors are often required. To elucidate the effect of norepinephrine (NE) on the cerebral circulation in patients undergoing CEA, regional oxygen saturation (rSO2) in bilateral frontal poles was monitored by near infrared spectroscopy during NE infusion.

Methods: Seven patients undergoing CEA were enrolled.

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An oil-in-water (O/W) emulsion, in which the oil phase is semi-solid fat, is easily destabilized when stored below the crystallization temperature of the oil phase. Such destabilization, characterized by loss of fluidity at chilled temperature and oil-water separation after re-heating, is caused by inter-droplet bridging of fat crystals protruding out of the emulsion droplets. In the present study, we found that the simultaneous use of additives of highly hydrophobic sucrose oligoester (SOE; P-170) and highly hydrophilic SOE (P-1670) containing palmitic acid moiety remarkably retarded the crystallization-induced destabilization of the O/W emulsion that contains palm-mid-fraction (PMF) as the oil phase.

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Background: Dexmedetomidine could be beneficial for preoperative sedation of patients with aneurysmal subarachnoid hemorrhage (SAH) because of its sympathetic suppressive effect without respiratory depression.

Methods: Thirteen patients were sedated with continuous intravenous administration of dexmedetomidine (group D) and 13 were with intermittent intravenous administration of diazepam and pentazocine (group C).

Results: Blood pressure (BP) and heart rate (HR) on admission to OR in group D were lower than those in group C.

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Background: The adaptation of patients with acute myocardial infarction (AMI) to a phase I rehabilitation program has not been widely assessed.

Methods And Results: Forty-two male patients (62+/-8 years) with AMI were classified as exercise tolerant (group A, n=25) or excessive response (systolic blood pressure (SBP) increase >30 mmHg during exercise; group B, n=17). Hemodynamic parameters during exercise using a cycle-ergometer were monitored for the first 3 days.

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