Publications by authors named "Karasawa F"

This study focused on evaluating the catalytic properties for the reverse water gas shift reaction (RWGS: CO + H → CO + HO Δ = 42.1 kJ mol) in the presence of hydrogen sulfide (HS) over a Fe/CeO catalyst, commercial Cu-Zn catalyst for the WGS reaction (MDC-7), and Co-Mo catalyst for hydrocarbon desulfurization. The Fe/CeO catalyst exhibited a relatively high catalytic activity to RWGS, compared to the commercial MDC-7 and Co-Mo catalysts.

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Backgrounds: Chest low-dose CT screening (LDCTS) has been finding unprecedented numbers of peripheral non-small cell lung cancers (NSCLC) at an early stage and increased the number of patients with surgical indication. It is important to explore the influence of preoperative watchful-waiting time (WWT) on surgical outcomes. Objective is to clarify relationship between WWT and surgical outcomes of LDCTS-finding NSCLC from the view point of treatment delay.

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Background: It is a big topic for general thoracic surgery whether still curability can be obtained by limited resection for peripheral small-sized nodules of non-small cell lung cancer (NSCLC) in the current era of frequent computed tomography (CT) use. Accumulation of information on problematic cases would be meaningful for surgeons to select better surgical procedures.

Case Presentation: A 69-year-old man was pointed out an enlarged 2.

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Background: Solitary metastasis of a malignancy to the spleen is rare, particularly for gastric cancer. Only a few case reports have documented isolated splenic metastasis from early gastric cancer. We describe a case of splenic metastasis from early gastric cancer.

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A 68-year-old man was admitted to our hospital after testing positive in a fecal occult blood test. He was subsequently diagnosed with advanced signet ring cell carcinoma of the appendix with disseminated peritoneal disease and ascites. Weekly chemotherapy with S-1 was commenced, and after three courses, the tumor shrunk in size and the ascites decreased.

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Gastric gland mucin secreted from the lower portion of the gastric mucosa contains unique O-linked oligosaccharides (O-glycans) having terminal α1,4-linked N-acetylglucosamine residues (αGlcNAc). Previously, we identified human α1,4-N-acetylglucosaminyltransferase (α4GnT), which is responsible for the O-glycan biosynthesis and characterized αGlcNAc function in suppressing Helicobacter pylori in vitro. In the present study, we engineered A4gnt(-/-) mice to better understand its role in vivo.

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Oxaliplatin in combination with 5-fluorouuacil and leucovorin (FOLFOX) is one of the most commonly used first-line chemotherapies for patients with advanced or metastatic colorectal cancer. Pulmonary toxicity, including interstitial pneumonia (IP)/peumonitis, is a very rare complication. We report a case of fatal IP associated with FOLFOX therapy in a patient with metastatic rectal cancer.

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Introduction: Anorectal malignant melanoma (AMM) is a relatively rare disease. Because of its poor prognosis, the optimal surgical treatment for AMM is still controversial and difficult to determine. In this paper, we report five cases of AMM that have been treated by surgery and/or other methods at Shinshu University Hospital within the last decade.

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Several studies have shown that UV irradiation may be effective for preventing vascular restenosis or vasopasm. However, the long-term effects of UV light on the physiological properties of vessels such as arterial tension have not been elucidated. We therefore studied the long-term effects of UV using rat carotid arteries treated with UV-B light (wavelength = 313 nm, total energy = 14 mJ/mm2).

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Purpose: The effects of nonsteroidal antiinflammatory drugs (NSAIDs) on pain from propofol injection are controversial, partially because NSAIDs themselves cause injection pain. We evaluated the effects of flurbiprofen axetil (LFP), a prodrug of an NSAID, on pain induced by intravenous propofol injection, because LFP produces little pain on injection.

Methods: A randomized, double-blind, controlled trial was undertaken in patients who were assigned to one of three groups ( n = 50 in each).

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Background And Objective: There are little data on nitrous oxide (N2O) concentrations in neonatal blood at delivery. We investigated the effects of the time elapsing between the induction of anaesthesia and delivery (the I-D interval) on umbilical blood N2O concentrations.

Methods: Maternal and neonatal blood N2O concentrations were measured in 27 patients undergoing Caesarean section under N2O 67% anaesthesia.

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Background And Objective: Isoflurane is commonly used for neurosurgery but the effects of sevoflurane on human cerebral blood flow and cerebral metabolic rate of oxygen have not been fully evaluated. We therefore assessed the effects of sevoflurane and isoflurane on global cerebral blood flow and cerebral metabolic rate of oxygen in patients without noxious stimuli or neurological disorders.

Methods: General anaesthesia was induced with midazolam (0.

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Background And Objective: When the endotracheal tube cuff is repeatedly aspirated to avoid excessive cuff pressure during nitrous oxide anaesthesia, a stable cuff pressure is eventually achieved. We assessed the time required to achieve a stable cuff pressure after repeated cuff deflation.

Methods: During 67% nitrous oxide and oxygen anaesthesia, air-filled cuffs of a standard tracheal tube (Mallinckrodt Hi-Contour) were repeatedly deflated every 30 min for the first 3 or 4 h to inhibit excessive pressure (Groups Def-3 or Def-4, respectively, n = 10 for each); the cuff pressure was monitored for an additional 3 h.

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Background And Objective: The mechanism underlying stable cuff pressure in the Brandt rediffusion endotracheal tube during anaesthesia with nitrous oxide is not fully understood. The present study assessed changes in gas concentrations in the cuff during and after nitrous oxide anaesthesia.

Methods: The pressure of an air-filled Brandt endotracheal tube cuff was measured; anaesthesia was maintained with nitrous oxide 67% and oxygen 33% for 6 h in the Continuous Group; oxygen was substituted for nitrous oxide after 3 h of nitrous oxide anaesthesia in the Discontinuous Group (n = 8 for each).

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Background And Objective: Phosphodiesterase-III inhibitors and dobutamine effectively improve cardiac function in patients with cardiac failure, but they are limited by possible hypotensive effects. We tested the hypothesis that dopamine contributes to stabilizing milrinone-induced haemodynamic changes.

Methods: Nine patients undergoing major surgery were anaesthetized using nitrous oxide and oxygen supplemented with isoflurane 1-2%.

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The Brandt tube system can limit excessive cuff pressure during nitrous oxide (N(2)O) anesthesia, but there is a lack of data assessing whether the Brandt tube system avoids cuff deflation after cessation of N(2)O administration. In this study, we recorded air-filled cuff pressures of the Mallinckrodt Brandt or Hi-Contour (control) tracheal tubes (Mallinckrodt, Athlone, Ireland) during 67% N(2)O anesthesia and the cuffs were aspirated if the cuff pressure exceeded 22 mm Hg; 180 min later, O(2) was substituted for N(2)O. The cuff pressure of both groups significantly decreased after N(2)O anesthesia but the time required for the cuff pressure to return to the initial pressure was longer in the Brandt group than in the control group (76.

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Purpose: To compare the hemodynamic effects of dopamine with those of dobutamine when administered with milrinone in patients undergoing non-cardiac surgery.

Methods: In 14 patients undergoing major surgery during anesthesia with isoflurane, milrinone (50 microgram*kg(-1) followed by 0.25 microgram*kg(-1)*min(-1)) was administered.

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Background: The Brandt tracheal tube keeps cuff pressure constant during anaesthesia, but the mechanisms have not been examined. We assessed volume, pressure and gas concentration in the cuff and pilot balloon using the Brandt system.

Methods: The pressure in an air-filled cuff of the Brandt system (Mallinckrodt Brandt tracheal tube, n = 60) was recorded during anaesthesia with 67% nitrous oxide; gas volume and concentration in cuffs and balloons were measured for up to 12 h from the start of anaesthesia.

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Background: Effects of propofol on human cerebral blood flow (CBF), cerebral metabolic rate of oxygen (CMRO2), and blood flow-metabolism coupling have not been fully evaluated. We therefore assessed the effects of propofol on total-CBF and CMRO2 in patients without noxious stimuli and neurologic disorders.

Methods: General anesthesia was induced with midazolam (0.

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Unlabelled: Although a nitrous oxide (N(2)O) gas-barrier cuff effectively limits the increase of cuff pressure during N(2)O anesthesia, there are few data assessing whether an N(2)O gas-barrier cuff is more beneficial for stabilizing intracuff pressure than standard endotracheal tubes when cuffs are repeatedly deflated to stabilize pressure during N(2)O anesthesia. In the present study, the pressure of air-filled standard-type cuffs (Trachelon; Terumo, Tokyo, Japan) and N(2)O gas-barrier type endotracheal tube cuffs (Profile Soft-Seal Cuff [PSSC]; Sims Portex, Kent, UK) was measured during 67% N(2)O anesthesia (n = 8 in each), during which the cuffs were repeatedly deflated every 30 min (Trachelon) or 60 min (PSSC) for the first 3 or 4 h. After aspirating the cuffs for 3 h, the cuff pressure exceeded 22 mm Hg in more than half of the patients in both groups.

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Unlabelled: Deflationary phenomena of the endotracheal tube cuff may occur after inspired nitrous oxide (N(2)O) concentrations are reduced, but deflationary phenomena of the double-lumen tube (DLT) cuff have not been investigated. In this study, tracheal and bronchial cuffs of left-sided Mallinckrodt (Athlone, Ireland) DLTs were inflated with air, 40% N(2)O, or 67% N(2)O (Air, N40, or N67 groups, respectively) in 24 patients undergoing thoracic surgery; 40 min later, O(2) was substituted for N(2)O in some of the patients in the N40 group (N40-c group). Intracuff gas volumes, N(2)O concentrations, and cuff compliance were also measured.

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A 36-yr-old pregnant woman with blood coagulation factor XII deficiency was scheduled to undergo cesarean section. Preoperative blood coagulation scan revealed prolonged activated partial thrombin time of 105.6 s (control, 30.

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We assessed the effects of sevoflurane and enflurane, i.e. halogenated volatile anesthetics, on blood pressure, heart rate, and renal sympathetic nerve activity (RSNA) in rabbits.

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We assessed the efficacy of inflating cuffs with a nitrous oxide gas mixture to minimise changes in intracuff pressure during anaesthesia. Patients were randomly assigned to one of five groups of 15 subjects each, and the trachea was intubated with the Profile Soft-Seal Cuff, Hi-Contour, Reinforced, Sheridan or Trachelon tracheal tubes. Cuffs were inflated with 40% nitrous oxide and cuff pressure was measured during anaesthesia with 67% nitrous oxide.

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Unlabelled: After cessation of nitrous oxide (N(2)O) administration, intracuff pressure of the endotracheal tube may decrease through rediffusion of N(2)O. There may then be an increased risk for air leaks, aspiration of gastric contents, or both. In this study, the time required for intracuff pressure to decrease by 50% (T(1/2)) after substituting oxygen for N(2)O inspired was estimated with the least-squares method.

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