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S Kihara

Publications and source records attributed to S Kihara.

At least 55 records · Page 3Linked to original sources
PubMed2000

Identification of a GPI-anchored type HDL-binding protein on human macrophages.

To identify the HDL3-binding proteins on human macrophages, we examined the involvement of GPI-anchored protein in the binding of HDL3, and tried to purify HDL3-binding protein. From membrane fractions of macrophages, we obtained 80- and 130-kDa HDL3-binding proteins by ligand blotting. Treatment of macrophages with phosphatidylinositol-specific phospholipase C (PI-PLC) significantly decreased the specific HDL3-binding in a dose-dependent manner. Furthermore, treatment with mannosamine, which blocks GPI-anchor formation, decreased specific HDL3-binding in a dose-dependent manner. PI-PLC treatment released from the cells the proteins with an M(r) of 80 kDa, which could also bind HDL3. PI-PLC as well as mannosamine treatment markedly reduced cholesterol efflux from macrophages in association with the decreased HDL-binding. Using HDL3-affinity chromatography, we purified 80-kDa GPI-anchored type HDL3-binding protein. In summary, we demonstrate the implication of 80-kDa GPI-anchored protein in the binding of HDL3 to human macrophages, which might have some role in reverse cholesterol transport.

Binding Sites↗
PubMed2000

Surgical angioplasty of ruptured left anterior descending coronary artery without cardiopulmonary bypass.

We report a case of successful off-pump surgical angioplasty in the left anterior descending coronary artery using a saphenous vein patch. A 49-year-old male with left main disease and severe cerebrovascular stenosis underwent off-pump bypass to the left anterior descending artery. Postoperative angiography showed anastomotic stenosis where balloon angioplasty was performed. However, it resulted in coronary perforation complicated with epicardial tamponade, and emergency off-pump surgical angioplasty was performed. This case demonstrated that coronary arterial rupture could be managed by surgical angioplasty without cardiopulmonary bypass when coronary artery perforation occurred.

Angioplasty↗
PubMed2000

Genomic structure and mutations in adipose-specific gene, adiponectin.

BACKGROUND: Adiponectin is a collagen-like plasma protein specifically synthesized in adipose tissue. Plasma adiponectin concentrations are decreased in obesity whereas it is adipose-specific. OBJECTIVE: To clarify the significance of the genetic variations in adiponectin gene on its plasma concentrations and obesity. SUBJECTS: Two hundred and nineteen unrelated adult Japanese subjects (123 men and 96 women, age: 20-83 y, BMI: 16-43 kg/m2) including 77 obese subjects (BMI>26.4 kg/m2). MEASUREMENT: Human adiponectin gene was isolated from PAC DNA pools. Mutations in the adiponectin gene were screened by direct sequencing or restriction-fragment polymorphism. The levels of plasma adiponectin were determined by the enzyme-linked immunosorbent assay (ELISA). RESULTS: Adiponectin gene spanned 17 kb on chromosome 3q27, consisting of three exons and two introns. Within 2.1 kb of the 5'-flanking region, there were two octamer elements present in the promoter of adipsin. Two nucleotide changes were identified. One was a polymorphism (G/T) occurring in exon 2, and the other was a missense mutation (R112C) in exon 3. The mean plasma adiponectin levels of the subjects carrying G allele were low (G/G: 4.5 microg/ml; G/T: 5.9 microg/ml; and T/T: 6.3 microg/ml), but were not statistically significant. The allelic frequency between the obese and the non-obese showed no significant difference. The subject carrying R112C mutation showed markedly low concentration of plasma adiponectin. CONCLUSION: Two nucleotide changes have been identified in the adiponectin gene. G/T polymorphism in exon 2 was associated with neither plasma adiponectin concentrations nor the presence of obesity. A subject carrying missense mutation (R112C) showed markedly low plasma adiponectin concentration.

Adipocytes↗
PubMed2000

A comparison of blind and lightwand-guided tracheal intubation through the intubating laryngeal mask.

We have tested the hypothesis that intubation success rates, haemodynamic changes, airway complications and postoperative pharyngolaryngeal morbidity differ between blind and lightwand-guided intubation through the intubating laryngeal mask airway. One hundred and twenty paralysed anasthetised adult patients (ASA I-II, no known or predicted difficult airways) were assigned in a random manner to one of two equal-sized groups. In the blind group, patients were intubated blindly through the intubating laryngeal mask airway. In the lightwand group, patients were intubated through the intubating laryngeal mask airway assisted by transillumination of the neck with a lightwand. A standard sequence of adjusting manoeuvres was followed if resistance occurred during intubation or if transillumination was incorrect. The number of adjusting manoeuvres, time to intubation, intubation success rates, haemodynamic changes (pre-induction, pre-intubation, postintubation), oesophageal intubation, mucosal trauma (blood detected), hypoxia (oxygen saturation < 95%) and postoperative pharyngolaryngeal morbidity (double-blinded) were documented. Overall intubation success was similar (blind, 93%; lightwand, 100%), but time to successful intubation was significantly shorter (67 vs. 46 s, p = 0. 027) and the number of adjusting manoeuvres was significantly fewer (p = 0.024) in the lightwand group. There were no significant differences in blood pressure or heart rate between the groups at any time. Oesophageal intubation occurred more frequently in the blind group (18 vs. 0%, p = 0.002). The incidence and severity of mucosal injury, sore throat and hoarseness were similar between the groups. We conclude that lightwand-guided intubation through the intubating laryngeal mask is superior to the blind technique.

Adult↗
PubMed2000

Haemodynamic responses to the intubating laryngeal mask and timing of removal.

We determined (a) the haemodynamic responses to intubating laryngeal mask (ILM) airway insertion/intubation and removal in anaesthetized patients, and (b) whether the timing of ILM removal influences these responses. One-hundred and twenty patients without cardiovascular disease were studied. ILM airway insertion/intubation was 5 min after induction with propofol 2 mg kg(-1) and maintenance of anaesthesia with sevoflurane 2% in oxygen 33% and nitrous oxide. Patients were randomly assigned for removal of the intubating laryngeal mask airway at 1, 3 and 5 min after successful intubation. Systolic and diastolic arterial pressures and heart rate were recorded preinduction (baseline), before ILM airway insertion/intubation, at 1-min intervals after insertion/intubation, and at 1-min intervals for 5 min after ILM removal. ILM insertion was successful at the first attempt in all patients, but 46 patients required more than one intubation attempt. Compared with baseline values, there were no increases in systolic or diastolic arterial pressure, but there was an increase in heart rate 1 min after ILM insertion/intubation (9%, P<0.001) and 1 min after ILM removal (8%, P<0.01). There was a significant increase in systolic and diastolic pressures and heart rate 1 min after ILM insertion/intubation (30%, 31% and 15%; all: P<0.002) compared with before ILM insertion/intubation values and 1 min after ILM removal (9%, 8% and 7%; all P<0.05) compared with 1 min after ILM insertion/intubation values. Removal of the ILM 1 min after successful intubation resulted in higher arterial pressure compared with removal at 3 min (systolic arterial pressure 10% higher for 1 min, P = 0.01) and 5 min (systolic arterial pressure 10-23% higher for 3 min, P<0.01; diastolic arterial pressure 10-20% higher for 4 min, P>0.02), but there were no differences in heart rate between groups. Systolic and diastolic arterial pressures were greater if more than one intubation attempt was required. Early removal or multiple intubation attempts did not exceed baseline haemodynamic values. We conclude that ILM insertion/intubation and removal in anaesthetized patients produces little or no haemodynamic response, even if multiple intubation attempts are required. The timing of removal exerts a small, but clinically unimportant influence on these responses.

Adult↗
PubMed2000

Effects of a thromboxane receptor antagonist (NT-126) and a thromboxane synthase inhibitor (OKY-O46) on protamine-induced circulatory changes in dogs.

OBJECTIVE: To examine whether a thromboxane receptor antagonist, NT-126, or a thromboxane synthase inhibitor, OKY-046, prevents circulatory changes caused by protamine reversal of heparin and to evaluate the significance of thromboxane generation in the phenomena. DESIGN: Prospective, randomized, controlled, animal study. SETTING: A university research laboratory. PARTICIPANTS: Twenty-four adult mongrel dogs. INTERVENTIONS: According to the pretreatments, the animals were divided into 3 groups (n = 8 in each): (1) control (normal saline); (2) NT-126, 0.01 mg/kg; and (3) OKY-046, 1 mg/kg. Under general anesthesia, all animals were anticoagulated with intravenous heparin, 200 IU/kg, 5 minutes before the pretreatment. Five minutes after the pretreatment, protamine sulfate, 2 mg/kg, was administered intravenously over 10 seconds. Hemodynamic variables were recorded repeatedly until 60 minutes after the protamine. Plasma thromboxane B2 level was determined at baseline and 10 minutes after protamine injection. MEASUREMENTS AND MAIN RESULTS: The average values of mean arterial blood pressure and mean pulmonary artery pressure among the 3 groups in each period and values in each group over the study period were not significantly different. There was weak correlation between maximum percent increases in systolic pulmonary artery pressure or maximum percent decreases in systolic arterial blood pressure for 5 minutes after the protamine versus percent increases in plasma thromboxane B2 level. CONCLUSION: Neither NT-126 nor OKY-046 appears to be effective in preventing protamine-induced circulatory changes in this dog model, suggesting that thromboxane generation alone is not responsible for the phenomena.

Animals↗
PubMed2000

An adipocyte-derived plasma protein, adiponectin, adheres to injured vascular walls.

Adipose tissue secretes a variety of proteins into the bloodstream. We have previously reported a novel cDNA, apM1 (adipose most abundant gene transcript 1), which is specifically and abundantly expressed in adipose tissue [1]. Primary structure analysis predicted that the apM1 gene product possesses significant homology to collagens VIII, X and complement factor C1q, and we named it adiponectin. In the current study, we analyzed characteristics of adiponectin in vitro and in vivo. Adiponectin protein was proved to be secreted into the medium when the cDNA was transfected to COS cells. Anti-adiponectin cross-reactivities were abundantly detected in the human plasma. In solid-phase binding assays, adiponectin specifically bound to collagen types I, III and V, which are present in vascular intima. Immunohistochemical analysis revealed that adiponectin was detected in the walls of the catheter-injured vessels but not in the intact vascular walls. These data suggest that adiponectin is a plasma protein produced by adipose tissue and accumulates in vascular walls when the endothelial barrier is injured.

Adipocytes↗
PubMed2000

Reduction in standard MAC and MAC for intubation after clonidine premedication in children.

We examined the relative effects of different doses of oral clonidine on the MAC for endotracheal intubation (MACEI) and the MAC for skin incision (MAC) in children. We studied 90 children (15 in each group) (age range 2-8 yr, weight 10-27 kg, height 89-124 cm) who received one of three preanaesthetic medications: placebo (control), oral clonidine 2 micrograms kg-1, or oral clonidine 4 micrograms kg-1 100 min before anaesthesia. Anaesthesia was induced and maintained with sevoflurane in oxygen and air without i.v. anesthetics and neuromuscular relaxants. The end-tidal sevoflurane concentration was kept constant for > or = 15 min before tracheal intubation or skin incision. MACs were determined using Dixon's 'up-and-down method'. Mean (SD) MACEIs of sevoflurane were 2.9 (0.1)%, 2.5 (0.1)% and 1.9 (0.1)% (P < 0.05), and MACs were 2.3 (0.1)%, 1.8 (0.1)% and 1.3 (0.1)% (P < 0.05), respectively, in control, clonidine 2 micrograms kg-1 and clonidine 4 micrograms kg-1 groups. The MACEIs and MACs decreased dose-dependently. The MACEI/MAC ratio (1.4) was not affected by clonidine.

Adrenergic alpha-Agonists↗
PubMed2000

Segmental cervical spine movement with the intubating laryngeal mask during manual in-line stabilization in patients with cervical pathology undergoing cervical spine surgery.

UNLABELLED: We quantified the extent and distribution of segmental cervical movement produced by the intubating laryngeal mask (ILM) during manual in-line stabilization in 20 anesthetized patients with cervical pathology undergoing cervical spine surgery. All patients had neurological symptoms preoperatively. The ILM was inserted with the head and neck in the neutral position. Intubation was facilitated by transillumination of the neck with a lightwand. Cervical movement was recorded with single-frame lateral radiographic images taken 1) immediately before induction (baseline); 2) during ILM insertion (insertion); 3) when transillumination was first seen at the cricothyroid membrane (intubation A); 4) when the tube was being advanced into the trachea (intubation B); and 5) during ILM removal (removal). Radiographic images were digitized and the degree of flexion/extension and posterior movement measured for the occiput (C0) through to C5. During ILM insertion, C0-5 were flexed by an average of 1-1.6 degrees (all P < 0.05). During intubation A/B, C0-4 were flexed by an average of 1.4-3.0 degrees (all P < 0.01), but C5 was unchanged. During ILM removal, C0-3 were flexed by an average of 1 degree (all: P < 0.05), but C3-5 were unchanged. During insertion and intubation A/B, C2-5 were displaced posteriorly by an average of 0.5-1.0 mm (all: P < 0.05). During removal, there was no change at C1-5. Neurological symptoms improved in all patients. We conclude that the ILM produces segmental movement of the cervical spine despite manual in-line stabilization in patients with cervical spine pathology undergoing cervical spine surgery. This motion is in the opposite direction to direct laryngoscopy, suggesting that different approaches to airway management may be more appropriate depending on the nature of the cervical instability. IMPLICATIONS: The intubating laryngeal mask produces segmental movement of the cervical spine, despite manual in-line stabilization in patients with cervical spine pathology undergoing cervical spine surgery. This motion is in the opposite direction to direct laryngoscopy, suggesting that different approaches to airway management may be more appropriate depending on the nature of the cervical instability.

Aged↗
PubMed2000

The awakening concentration of sevoflurane in children.

UNLABELLED: Sevoflurane is frequently used as a rapidly acting drug for the induction of anesthesia. We investigated the awakening concentration (MAC-awake) of sevoflurane in ASA physical status I children (age range 2-10 yr). We also investigated the effects of two different doses of clonidine (2 and 4 microg/kg) on the MAC-awake of sevoflurane. Subjects were randomly divided into three groups and received placebo (n = 24), clonidine 2 microg/kg (n = 17), or clonidine 4 microg/kg (n = 22) orally, 100 min before the induction of anesthesia. Sedation scores were estimated, by using a five-point scale, after entry into the operating room, and anesthesia was induced and maintained with sevoflurane in oxygen and balanced nitrogen, without an additional anesthetic. After surgery, end-tidal sevoflurane was decreased stepwise by 0.2% at 15-min intervals, a standardized verbal command was played to the patients, and the MAC-awake was determined. The MAC-awake of sevoflurane alone was 0. 78% +/- 0.24% (mean +/- SD), which decreased to 0.36% +/- 0.09% and 0.36% +/- 0.16% (both P <0.0001, compared with the control group) after premedication with the small and large doses of clonidine, respectively. The lack of any dose-response relationship might be explained by a plateau effect. IMPLICATIONS: The awakening concentration of sevoflurane in unpremedicated children was 0.78%. Oral clonidine premedication at a dose of 2 microg/kg reduced the awakening concentration to 0.36%. However, an additional decrease in this value was not observed after the administration of the larger dose of clonidine premedication (4 microg/kg).

Administration, Oral↗
PubMed2000

Localization of CD9, an enhancer protein for proheparin-binding epidermal growth factor-like growth factor, in human atherosclerotic plaques: possible involvement of juxtacrine growth mechanism on smooth muscle cell proliferation.

Heparin-binding epidermal growth factor (EGF)-like growth factor (HB-EGF), a member of the EGF family, has a potent mitogenic activity for vascular smooth muscle cells (SMCs). We previously reported that HB-EGF is involved in atherogenesis of human aorta and coronary arteries. ProHB-EGF (the membrane-anchored form of HB-EGF) has also been demonstrated to possess a mitogenic activity, which is approximately 30-fold increased when coexpressed with CD9 in mouse L cells. Thus, in the process of atherogenesis, CD9 may be involved in the proliferation of SMCs. We immunohistochemically investigated the localization of CD9 and proHB-EGF in the human aorta and coronary arteries. In normal aorta and coronary arteries, CD9 immunostaining was virtually negative, whereas proHB-EGF immunostaining was positive, especially in the arteries of babies. In contrast, in atherosclerotic lesions, some intimal SMCs were strongly positive for CD9 and proHB-EGF immunostaining. The juxtacrine growth activities of human aortic SMCs were inhibited in vitro by adding neutralization antibodies for CD9 or adding the specific inhibitor of HB-EGF. Besides, coexpressed CD9 and proHB-EGF cells markedly incorporated [(3)H]thymidine into the SMCs. CD9 is localized immunohistochemically in the SMCs of the atherosclerotic aorta and coronary arteries. CD9, when coexpressed with proHB-EGF, enhances proHB-EGF activities for SMC growth in a so-called juxtacrine manner in vitro and may be involved in atherogenesis.

Animals↗
PubMed2000

Plasma concentrations of a novel, adipose-specific protein, adiponectin, in type 2 diabetic patients.

Adiponectin is a novel, adipose-specific protein abundantly present in the circulation, and it has antiatherogenic properties. We analyzed the plasma adiponectin concentrations in age- and body mass index (BMI)-matched nondiabetic and type 2 diabetic subjects with and without coronary artery disease (CAD). Plasma levels of adiponectin in the diabetic subjects without CAD were lower than those in nondiabetic subjects (6.6+/-0.4 versus 7.9+/-0.5 microg/mL in men, 7.6+/-0.7 versus 11.7+/-1.0 microg/mL in women; P<0.001). The plasma adiponectin concentrations of diabetic patients with CAD were lower than those of diabetic patients without CAD (4.0+/-0.4 versus 6.6+/-0.4 microg/mL, P<0.001 in men; 6.3+/-0.8 versus 7.6+/-0. 7 microg/mL in women). In contrast, plasma levels of leptin did not differ between diabetic patients with and without CAD. The presence of microangiopathy did not affect the plasma adiponectin levels in diabetic patients. Significant, univariate, inverse correlations were observed between adiponectin levels and fasting plasma insulin (r=-0.18, P<0.01) and glucose (r=-0.26, P<0.001) levels. In multivariate analysis, plasma insulin did not independently affect the plasma adiponectin levels. BMI, serum triglyceride concentration, and the presence of diabetes or CAD remained significantly related to plasma adiponectin concentrations. Weight reduction significantly elevated plasma adiponectin levels in the diabetic subjects as well as the nondiabetic subjects. These results suggest that the decreased plasma adiponectin concentrations in diabetes may be an indicator of macroangiopathy.

Adiponectin↗
PubMed2000

Tracheal intubation with the Macintosh laryngoscope versus intubating laryngeal mask airway in adults with normal airways.

We tested the hypothesis that haemodynamic changes to intubation and postoperative pharyngolaryngeal morbidity are similar for blind intubating laryngeal mask (ILM)-guided compared with laryngoscope-guided tracheal intubation in adults with normal airways. We also compared intubation success rates and airway complications. One-hundred and fifty paralysed, anaesthetized adult patients undergoing elective surgery were randomly assigned to one of three equal-sized groups: 1. blind intubation via the ILM using a straight, silicone tube; 2. intubation with a Macintosh laryngoscope using a straight silicone tube and 3. intubation with a Macintosh laryngoscope using a polyvinyl chloride tube (controls). A standard sequence of adjusting manoeuvres was followed if intubation was difficult. The number of adjusting manoeuvres and intubation attempts, time to intubation, intubation success rate (first attempt and within 3 min), haemodynamic changes (pre-induction, post-induction, post-intubation), oesophageal intubation, mucosal trauma (blood detected), hypoxia (SpO2 < 95%) and postoperative pharyngolaryngeal morbidity (double-blinded) were documented. Time to successful intubation was longer (57 vs 35 s), and more intubation attempts were required in the ILM group (P < 0.0001). The intubation success rate was 100% (all first attempt) for the laryngoscope groups and 94% (56% first attempt) for the ILM group. There were no significant differences in heart rate or blood pressure among groups. Oesophageal intubation (26 v 0%) and mucosal trauma (19 v 2%) were more common in the ILM group. Hypoxia and postoperative pharyngolaryngeal morbidity were similar among groups. Blind intubation through the ILM offers no advantages over the Macintosh laryngoscope for adult patients requiring intubation for elective surgery with normal airways, but it is a feasible alternative.

Adult↗
PubMed2000

[Early and late results of combined valvular and coronary artery operations].

A total of 122 patients with ischemic heart disease underwent valvular surgery. Thirty-nine had combined CABG and aortic valve surgery (included Bentall method), 72 had CABG and mitral valve operations, and 8 patients had CABG and double or triple valve operations. Only 3 patients for ruptured papillary muscle due to acute myocardial infarction had isolated mitral valve replacement. Early mortality was 5.1% AV, 2.8% MV and 12.5% DTV in the combined groups and 0% in the valve only group. The grafts patency rate was 93.5%. Univariate analysis of risk factors selected in the dialysis patients and the patients age older than 65 years as the strongest predictors for early death. At the mean follow up period of 5.4 +/- 4.8 year after surgery, the 5-year all death free rates were 57.9 +/- 9.6% AV, 69.6 +/- 5.8% MV and 75.0 +/- 15.3% DTV. The 5-year cardiac death free rates were 73.8 +/- 9.0% AV, 77.5 +/- 5.4% MD and 75.0 +/- 15.3% DTV.

Adolescent↗
PubMed1999

Paradoxical decrease of an adipose-specific protein, adiponectin, in obesity.

We isolated the human adipose-specific and most abundant gene transcript, apM1 (Maeda, K., et al., Biochem. Biophys. Res. Commun. 221, 286-289, 1996). The apM1 gene product was a kind of soluble matrix protein, which we named adiponectin. To quantitate the plasma adiponectin concentration, we have produced monoclonal and polyclonal antibodies for human adiponectin and developed an enzyme-linked immunosorbent assay (ELISA) system. Adiponectin was abundantly present in the plasma of healthy volunteers in the range from 1.9 to 17.0 mg/ml. Plasma concentrations of adiponectin in obese subjects were significantly lower than those in non-obese subjects, although adiponectin is secreted only from adipose tissue. The ELISA system developed in this study will be useful for elucidating the physiological and pathophysiological role of adiponectin in humans.

Adiponectin↗
PubMed1999

Bleeding from a tear in the gastric mucosa caused by transoesophageal echocardiography during cardiac surgery: effective haemostasis by endoscopic argon plasma coagulation.

We present an unusual complication of transoesophageal echocardiography (TOE) during cardiac surgery. Although the patient had no oesophageal or gastrointestinal disease, a gastric mucosal tear of approximately 2 cm long occurred in the mucosa just distal to the gastrooesophageal junction caused by the TOE probe. Bleeding from the tear was stopped using endoscopic argon plasma coagulation.

Argon↗
PubMed1999

Dural closure with nonpenetrating clips prevents meningoneural adhesions: an experimental study in dogs.

OBJECTIVE: Meningospinal and cranial dural adhesions were compared in a canine model, after duraplasty using nonpenetrating clips or penetrating needles and sutures. METHODS: Fourteen dogs underwent bilateral craniotomies and duraplasties, with implantation of dural prostheses (DuraGuard; Biovascular Corp., Minneapolis, MN), using either 6-0 silk sutures or titanium clips (DuraClose; Surgical Dynamics, Norwalk, CT). Fourteen other dogs underwent L3-L4 laminectomies; three longitudinal dural incisions were closed with 6-0 silk sutures, 6-0 polyglactin 910 (Vicryl) sutures, or clips. Groups of eight dogs (four cranially treated and four spinally treated) were killed 6, 12, 24, and 52 weeks after surgery, and specimens were collected for study after perfusion and fixation (two cranial and two spinal dural reconstructions at 52 wk). Evaluations included assessment of the appearance of approximated dural margins and responses to clips, sutures, and dural prostheses (inflammation, foreign body reaction, fibrosis, and severity of meningospinal/meningocerebral adhesions). Data were evaluated using the Wilcoxon signed-rank and McNemar tests. RESULTS: Duraplasties with clips displayed significantly less extensive acute and chronic inflammation, foreign body reaction, and meningoneural adhesions than did repairs with needles and sutures. CONCLUSION: This report is the first long-term experimental study comparing two fundamentally different methods for dural repair in a relevant animal model.

Animals↗