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S Kawachi

Publications and source records attributed to S Kawachi.

At least 19 recordsLinked to original sources
PubMed1999

Role of inducible nitric oxide synthase in leukocyte extravasation in vivo.

Several recent studies have suggested that nitric oxide (NO) derived from the inducible isoform of NO synthase (NOS) may act as an endogenous modulator of the inflammatory response by inhibiting adhesion of leukocytes to endothelial cells in vitro. Few studies have addressed specifically the role of iNOS in regulating leukocyte recruitment in vivo in a model of acute inflammation. Thus, the objective of this study was to assess the role of iNOS in modulating neutrophil (PMN) extravasation in an oyster glycogen-induced model of acute peritonitis in rats. Data obtained in the present study demonstrates that injection (IP) of oyster glycogen induces massive and selective PMN recruitment into the peritoneal cavity of rats at 6 hrs following OG administration. These extravasated cells were found to contain significant amounts of iNOS protein as assessed by Western blot analysis. Treatment of rats with the selective iNOS inhibitor L-iminoethyl-lysine (L-NIL) dramatically reduced NO levels in lavage fluid as measured by decreases in nitrate and nitrite concentrations without significantly affecting iNOS protein levels. Although L-NIL inhibited NO production by >70%, it did not alter oyster glycogen-induced PMN recruitment when compared to vehicle-treated rats. We conclude that PMN-associated, iNOS-derived NO does not play an important role in modulating extravasation of these leukocytes in this model of acute inflammation.

Acute Disease↗
PubMed1999

Total hip arthroplasty using bone cement containing tri-n-butylborane as the initiator.

We performed total hip arthroplasty (THA) using a special acrylic self-curing bone cement (Bonemite), which contains tri-n-butylborane as the initiator. Its maximum temperature at curing is lower than that of a conventional bone cement (CMW). Fifty-eight THAs using Bonemite and 35 THAs using CMW were followed up for more than 8 years (12.5 years on average). At the 10-year follow-up, the survival rates, using revision surgery or aseptic loosening impending revision as the endpoint for failure, were 92.2% for the patients in the Bonemite group and 91.0% for those in the CMW group. No statistical differences were observed between the patients in these two groups with regard to survival rate (p = 0.39). Bonemite showed no clear superiority compared with CMW, although the results suggest that Bonemite is safe and reliable for clinical use and stable in situ for long time.

Arthroplasty, Replacement, Hip↗
PubMed1999

Differential effects of troglitazone and D-chiroinositol on glucosamine-induced insulin resistance in vivo in rats.

Troglitazone and D-chiroinositol have been shown to exert antidiabetic effects by either potentiating or mimicking insulin action. We studied whether pretreatment with these compounds can prevent the deleterious effects of glucosamine on insulin action that may play an important role in hyperglycemia-induced insulin resistance. Normal Wistar rats were pretreated with troglitazone (100 mg/kg/d), D-chiroinositol (100 mg/kg/d), or placebo (saline) for 7 days. Glucosamine (50 micromol/kg/min) was then infused for 210 minutes, and a euglycemic glucose clamp was performed during the last 120 minutes. Pretreatment with troglitazone or D-chiroinositol had no effect on fasting plasma glucose or insulin or basal hepatic glucose output (HGO). Under the euglycemic-hyperinsulinemic (956+/-93 pmol/L) clamp condition, HGO in glucosamine-infused placebo-treated rats was not suppressed, but instead was increased over the basal level, indicative of hepatic insulin resistance. In contrast, HGO failed to increase during glucosamine infusion in rats pretreated with troglitazone but was not normally suppressed. This may indicate a partial improvement in the hepatic insulin resistance. D-Chiroinositol pretreatment had no effect on the glucosamine-induced increase in HGO. The glucose disposal rate (GDR) was 25% lower in rats infused with glucosamine versus saline-infused rats (25.5+/-2.5 v 34.1+/-2.0 mg/kg/min), indicative of peripheral insulin resistance. Pretreatment with D-chiroinositol (34.5+/-2.3 mg/kg/min) prevented the glucosamine-induced decrease in the GDR, indicating an improvement in peripheral insulin resistance. Troglitazone (25.2+/-3.3 mg/kg/min) was without effect. In conclusion, (1) in normal control rats, glucosamine infusion induced hepatic and peripheral insulin resistance; (2) D-chiroinositol, but not troglitazone, pretreatment prevented glucosamine-induced peripheral insulin resistance; and (3) troglitazone, but not D-chiroinositol, partially blocked the glucosamine-induced hepatic insulin resistance. D-Chiroinositol may provide a novel pharmacological approach to hexosamine-induced peripheral insulin resistance.

Animals↗
PubMed1999

Role of inducible nitric oxide synthase in the regulation of VCAM-1 expression in gut inflammation.

The objectives of this study were to assess the role of the inducible isoform of nitric oxide synthase (iNOS) on vascular cell adhesion molecule 1 (VCAM-1) expression in vivo in an acute model of inflammation induced in iNOS-deficient (iNOS-/-) mice and compare these data to those obtained by pharmacological inhibition of iNOS in a CD4+ T lymphocyte-dependent model of chronic colitis. VCAM-1 expression was quantified in vivo using the dual radiolabel monoclonal antibody technique. We found that intraperitoneal injection of 10 microg/kg tumor necrosis factor-alpha (TNF-alpha) enhanced VCAM-1 expression by approximately twofold in the colon, cecum, and stomach but not small intestine in iNOS-/- mice compared with TNF-alpha-injected wild-type mice. Injection of wild-type mice with 25 microg/kg TNF-alpha further enhanced VCAM-1 expression by approximately twofold compared with wild-type mice injected with 10 microg/kg TNF-alpha; however, VCAM-1 expression was not further enhanced in any gastrointestinal organ system in iNOS-/- mice. In a second series of experiments, we found that continuous inhibition of iNOS using oral administration of NG-iminoethyl-L-lysine did not alter the enhanced levels of VCAM-1 expression in the colon nor did it alter the severity of colonic inflammation in SCID mice reconstituted with CD4+, CD45RB(high) T cells. We conclude that iNOS may regulate VCAM-1 expression in acute inflammation; however, this effect is modest and tissue specific and occurs only when VCAM-1 expression is submaximal. iNOS does not appear to modulate VCAM-1 expression in an immune model of chronic colitis.

Animals↗
PubMed1998

Characteristic epiluminescent microscopic features of early malignant melanoma on glabrous skin. A videomicroscopic analysis.

OBJECTIVE: To investigate the characteristic epiluminescent microscopic features of early lesions of malignant melanoma affecting glabrous skin, which is the most prevalent site of the neoplasm in nonwhite populations. DESIGN: The epiluminescent microscopic features of various kinds of melanocytic lesions affecting glabrous skin were investigated using a videomicroscope. All the diagnoses were determined clinically and histopathologically using the standard criteria. SETTING: A dermatology clinic at a university hospital. PATIENTS: The following 130 melanocytic lesions consecutively diagnosed at our department were examined: 16 lesions of acral lentiginous melanoma, 6 lesions of malignant melanoma in situ, and 108 lesions of benign melanocytic nevus (acquired or congenital). MAIN OUTCOME MEASURE: The incidence of each characteristic epiluminescent feature was compared among disease categories. RESULTS: On epiluminescent microscopy, malignant melanoma in situ and the macular portions of invasive malignant melanoma showed accentuated pigmentation on the ridges of the skin markings, which are arranged in parallel patterns on glabrous skin. This "parallel ridge pattern" was found in 5 (83%) of 6 lesions of malignant melanoma in situ and in 15 (94%) of 16 lesions of malignant melanoma. The parallel ridge pattern was rarely found in the lesions of benign melanocytic nevus. Most benign melanocytic nevi showed 1 of the following 3 typical epiluminescent patterns: (1) a parallel furrow pattern exhibiting pigmentation on the parallel sulci of [he skin markings (54%), (2) a latticelike pattern (21%), and (3) a fibrillar pattern showing filamentous or meshlike pigmentation (15%). The remaining 11 benign nevi (10%) showed a nontypical pattern. CONCLUSION: Because epiluminescent microscopic features of early malignant melanoma on glabrous skin are characteristic, we can effectively detect early lesions using this noninvasive method.

Adult↗
PubMed1998

A new approach to dynamic graciloplasty.

The reestablishment of anal function by transposition of the gracilis muscle, combined with the implantation of electrodes and a neuromuscular stimulator (dynamic graciloplasty), has recently been developed. With this method, the transposed muscle maintains contraction by electrical stimulation to maintain neoanal pressure without fatigue. It is necessary to convert the fatigue-prone gracilis muscle to fatigue-resistant muscle by long-term electrical stimulation (conditioning). In most patients receiving dynamic graciloplasty, the conditioning is accomplished after the transposition. However, conditioning before graciloplasty should reduce the risk of ischemia in the transposed muscle after the graciloplasty and improve the outcome. This new sequence of procedures is described, in combination with J-pouch construction, in a patient who required abdominoperineal excision of the rectum for lower rectal cancer. The graciloplasty was performed after conditioning of the gracilis muscle in situ; the conditioning did not cause the patient discomfort and resulted in good anal function.

Adenocarcinoma↗
PubMed1998

The tracheal tube with a high-volume, low-pressure cuff at various airway inflation pressures.

When the tracheal tube with a high-volume, low-pressure cuff is used, the pressure exerted by the cuff on the tracheal wall is similar to the intracuff pressure, and the pressure is claimed to be lower than the capillary perfusion pressure; however, it is not known if this is the case when a high airway pressure is required. In a randomized, cross-over design, we studied 61 patients (31 men) and measured the intracuff pressures of the tracheal tube at various airway pressures. While the lungs were inflated at five different airway pressures in turn (10, 15, 20, 25 and 30 cm H2O), the cuff of the tracheal tube was inflated with air until it prevented an airleak ('just-seal' pressure). Intracuff pressures [median (range)] at airway pressures of 10, 15, 20, 25 and 30 cm H2O were 8 (0-20), 15 (4-20), 22 (6-32), 26 (11-52) and 31 (16-54) cm H2O, respectively, for men and 6 (0-20), 11 (0-20), 15 (0-24), 21 (0-32) and 25 (1-41) cm H2O, respectively, for women. Therefore, we conclude that the pressure exerted by the cuff of the tracheal tube on the tracheal wall is unlikely to exceed the capillary perfusion pressure (arbitrarily defined as 25 mmHg or 34 cm H2O) when the airway pressure is 25 cm H2O or less, but it may exceed the capillary perfusion pressure when the airway pressure is greater than 25 cm H2O.

Anesthesiology↗
PubMed1998

A case of an inflammatory variant of epidermolysis bullosa acquisita: chronic bullous dermatosis associated with nonscarring mucosal blisters and circulating IgG anti-type-VII-collagen antibody.

A 42-year-old man showed prominent blistering lesions of the mouth and esophagus in addition to a few bullous lesions of the skin. Direct immunofluorescence microscopy revealed distinct linear deposition of IgG and C3 at the epidermal basement membrane zone where slight deposition of IgA and IgM was also observed. In direct immunoelectron-microscopic examination, antibody was detected in the sublamina densa of the basement membrane zone. Immunoblot analysis with dermal extracts demonstrated that the patient's serum contained circulating IgG antibodies against the 290-kD protein, which comigrated with type VII collagen. The lesions healed without any scars. The results of these studies corresponded to the laboratory findings in epidermolysis bullosa acquisita (EBA), although the clinical features were distinct from classic EBA.

Adult↗
PubMed1997

Up-regulation of oxygen-derived free radicals by interleukin-1 in hepatic ischemia/reperfusion injury.

BACKGROUND: Oxygen-derived free radicals (FRs) are critical mediators of ischemia/reperfusion injury. Inflammatory cytokines have been shown to play important roles in tissue injury. To examine the relationship between FRs and interleukin-1 (IL-1) in hepatic ischemia/reperfusion injury, we used interleukin-1 receptor antagonist (IL-1ra) to block endogenous IL-1 production in a rat model of hepatic ischemia/reperfusion. METHODS: Female SD rats were subjected to 30 min of hepatic ischemia followed by reperfusion. The animals were divided into two groups, control group and IL-1ra-treated group, according to the rinse solution. In both groups, FR production, histological changes, and interactions between leukocytes and endothelial cells were analyzed in the course of reperfusion. RESULTS: In the control group, production of FRs increased significantly after 60 min of reperfusion. After 60 and 180 min of reperfusion, histological examination showed atrophy and degeneration of hepatocytes. Hepatic microcirculation demonstrated a marked increase in the number of leukocytes adherent to endothelial cells and of injured cells after reperfusion. In the IL-1ra-treated group, IL-1ra pretreatment markedly reduced FR production after 60 min of reperfusion, the number of leukocytes adherent to endothelial cells, and tissue injury. CONCLUSION: These data clearly show an important role for IL-1 in the induction of FR production, leukocyte adhesion, and tissue injury after hepatic ischemia/reperfusion injury.

Animals↗
PubMed1997

Efficacy of intraportal infusion of prostaglandin E1 to improve the hepatic blood flow and graft viability in porcine liver transplantation.

BACKGROUND: Prostaglandin E1 (PGE1) has been reported to have a protective effect in experimental and clinical models of liver damage. The aim of this study was to elucidate the effects of the intraportal infusion of PGE1 on hepatic blood flow and graft viability after orthotopic liver transplantation in pigs. METHODS: First, the hepatic arterial flow (HAF), portal venous flow (PVF), and liver tissue blood flow (LTBF) were measured during the continuous intravenous or intraportal infusion of PGE1. Second, two groups of pigs underwent orthotopic liver transplantation: group A, untreated controls; and group B, animals that received intraportal PGE1 for 2 hr after vascular reconstruction of the allograft. Changes in HAF, PVF, LTBF, and hepatic function were measured. RESULTS: The intraportal infusion of PGE1 significantly increased HAF and had no effect on blood pressure, PVF, or LTBF. In group B, HAF and LTBF increased significantly with time. In group A, HAF remained unchanged and a decrease in LTBF was observed. Group B exhibited a higher arterial ketone body ratio and a greater bile flow compared with group A. A significant elevation in serum glutamic oxaloacetic transaminase concentration was observed in group A, but not in group B. CONCLUSIONS: This study demonstrates that the intraportal infusion of PGE1 improves hepatic allograft blood flow, predominantly through an effect on HAF, and may improve graft viability after orthotopic liver transplantation.

Alprostadil↗
PubMed1997

Haemodynamic comparison of sevoflurane and isoflurane anaesthesia in surgical patients.

PURPOSE: To compare the haemodynamic responses to surgical incision during sevoflurane and isoflurane anaesthesia and to compare the haemodynamic effects of each anaesthetic alone with those obtained using an equipotent mixture of each anaesthetic plus N2O during steady-state surgical stimulation. METHODS: Twenty-four patients undergoing gastrectomy were randomized to receive sevoflurane (n = 12) or isoflurane (n = 12). At 1.5 MAC, haemodynamic measurements were performed before and after surgical incision. During intestinal anastomosis, patients in each group were given (in random order) either 1.5 MAC of the designated anaesthetic or 0.85 MAC of the volatile plus 0.65 MAC N2O. Haemodynamic measurements were repeated under each condition. RESULTS: One patient in the sevoflurane group and two in the isoflurane group were excluded from the incision study because of hypotension. In both groups, incision increased the heart rate (HR), mean arterial pressure, mean pulmonary arterial pressure (MPAP), pulmonary capillary wedge pressure (PCWP), cardiac index, and systemic vascular resistance index (SVRI). There were no intergroup differences in the effects of incision. Inclusion of N2O resulted in an increase of MPAP (P < 0.05) in both groups, an increase of central venous pressure and PCWP in the sevoflurane group (P < 0.005), and a decrease of HR (P < 0.005) and an increase of SVRI (P < 0.05) in the isoflurane group. There were no intergroup differences in the effects of N2O. CONCLUSIONS: At 1.5 MAC, sevoflurane and isoflurane do not prevent the haemodynamic response to incision. The haemodynamic effects of each volatile anaesthetic with N2O are minimal compared with those of equi-MAC volatile alone.

Adult↗
PubMed1997

Lidocaine tape relieves pain due to needle insertion during stellate ganglion block.

PURPOSE: To investigate the efficacy of lidocaine tape, a new preparation of lidocaine for cutaneous topical anaesthesia in the form of a self-adhesive tape, in alleviating the pain of needle insertion during stellate ganglion block. METHODS: In a double-blind, placebo controlled study, 30 adult outpatients undergoing stellate ganglion block were allocated to receive all of the following five treatments in random order: placebo tape applied to the intended site of the block (control), or lidocaine tape applied for 7, 15, 30, and 60 min. After the block was performed using a 24-gauge needle, the pain associated with needle insertion was assessed using a visual analogue scale (10 cm VAS) and the four-point verbal rating score (VRS 0-3). RESULTS: With placebo tape, the VAS and VRS scores were 2.4 +/- 1.27 (0.5-4.8) (mean +/- SD (range)) and 1.5 (1-2) (mean (range)), respectively. The pain scores were reduced (P < 0.01) by lidocaine tape after application for 7 min (1.6 +/- 1.06 and 1.0 (0-2) for VAS (mean +/- SD) and VRS (mean (range)), respectively), 15 min (1.5 +/- 1.00 and 1.0 (1-2)), 30 min (1.5 +/- 1.08 and 1.0 (1)), and 60 min (0.6 +/- 0.70 and 0.6 (0-1)). Skin erythema was more frequent with lidocaine tape than with placebo tape (seven minutes of lidocaine tape vs placebo tape, P < 0.05; 15, 30, and 60 min of lidocaine tape vs placebo, P < 0.0005). CONCLUSION: Stellate ganglion block without analgesia is fairly painful in some patients, even when using a 24-gauge needle, and needle pain is reduced by lidocaine tape after an application time of seven minutes or more.

Adult↗
PubMed1997

Spontaneous healing of pancreatic abscess after fistulization to the duodenal bulb.

A 70-year-old man was admitted to the hospital because of sudden, upper abdominal and back pain. Laboratory and image data indicated acute pancreatitis. Shortly after the admission, pancreatic and liver abscess with bacteremia developed. Antibiotic therapy seemed effective. A month later, spontaneous fistulization of the pancreatic abscess to the duodenal bulb was found by gastroduodenal fiberscopy. Injection of contrast medium into the duodenal orifice showed that the fistula was draining the abscess and that no other fistula formed from the abscess. Endoscopic retrograde cholangiopancreatogram indicated no fistula formation to the pancreatic duct. The pancreatic abscess became smaller and was not visible using computerized tomography and ultrasonography 3 months later and thereafter. Closure of the duodenal orifice was ascertained by the endoscopy. It is suggested that retrograde infection from the fistula was prevented by the single fistulization to the acidic duodenal bulb, which is not supposed to allow most bacterial growth. Pancreatic abscess usually necessitates operative treatment, even with fistulization to the alimentary tract. It seems likely that the single, small fistulization to the bulb, in addition to the lack of underlying disease and medical and nutritional support, facilitated the spontaneous healing process.

Abscess↗
PubMed1997

[Clinicopathological findings in 5 patients with acute eosinophilic pneumonia].

We studied 5 patients with acute eosinophilic pneumonia. Radiologic findings were Kerley's lines and pleural effusion on chest X-ray films, and interlobular septa on chest CT scans. Examination of transbronchial lung biopsy specimens revealed infiltration of eosinophils and lymphocytes into alveolar walls and edema of alveolar walls, interlobular septa, and perivascular connective tissue. The findings of interstitial edema were consistent with the radiological findings. Epithelial damage and bud-type intraluminal fibrosis were also seen, but residual alveolar structure was maintained. Bronchoalveolar lavage fluid contained abnormally high percentages of eosinophils and lympocytes. It also contained basophils and mast cells, which were not seen in fluid from normal subjects. Fluid from patients with chronic eosinophilic pneumonia had significantly fewer basophils than did fluid from those with acute eosinophilic pneumonia (p < 0.01). These findings suggest that release of chemical mediators from basophils plays a key role in interstitial edema in acute eosinophilic pneumonia.

Acute Disease↗
PubMed1996

Changes in the cerebral arteriovenous oxygen content difference by surgical incision are similar during sevoflurane and isoflurane anaesthesia.

PURPOSE: To investigate changes of cerebral arteriovenous oxygen content difference (AVDO2) induced by surgical incision and to determine carbon dioxide (CO2) reactivity of the cerebral circulation during sevoflurane and isoflurane anaesthesia. METHODS: Twenty-one ASA 1-2 patients undergoing elective surgery for supratentorial tumours were randomly allocated to receive either 1.3 MAC sevoflurane/N2O anaesthesia (n = 10) or equi-MAC isoflurane/N2O anaesthesia (n = 11). Before and after incision, haemodynamic measurements and AVDO2 determinations were performed. After opening the dura, AVDO2 was determined before and after the respiration rate was increased by 50%. RESULTS: Incision produced an increase in mean arterial pressure from 69 +/- 11 to 97 +/- 22 mmHg (mean +/- SD) (P < 0.0005) and from 71 +/- 6 to 89 +/- 12 mmHg (P < 0.0001) in the sevoflurane and isoflurane groups, respectively, whereas the heart rate increased from 60 +/- 9 to 72 +/- 8 bpm (P < 0.001) and from 65 +/- 6 to 70 +/- 7 bpm (P < 0.001), respectively. Arterial carbon dioxide tension (PaCO2) was increased from 33.6 +/- 2.3 to 34.6 +/- 1.8 mmHg (P < 0.05) with incision in the sevoflurane group. The AVDO2 was decreased from 6.5 +/- 1.6 to 5.3 +/- 1.6 vol% (P < 0.0005) in the sevoflurane group and from 6.7 +/- 1.1 to 6.0 +/- 1.1 vol% (P < 0.01) in the isoflurane group. The % change of AVDO2 was larger in the sevoflurane group than in the isoflurane group (-18.3 +/- 8.4% vs -9.1 +/- 9.0%; P < 0.05) but no difference remained after the post-incisional AVDO2 value of the sevoflurane group was corrected for pre-incisional PaCO2. Carbon dioxide reactivity, calculated as the percent change in AVDO2 per mmHg change in PaCO2, was 6.1 +/- 3.0%.mmHg-1 in the sevoflurane group and 5.9 +/- 2.4%.mmHg-1 in the isoflurane group (P = NS). CONCLUSIONS: Sevoflurane and isoflurane are associated with similar impairment of cerebral flow-metabolism coupling at incision, while CO2 reactivity is maintained during both anaesthetics.

Adult↗
PubMed1996

Changes in tracheal tube position during laparoscopic cholecystectomy.

The distance from the carina to the tip of the tracheal tube was measured with a fibreoptic bronchoscope in 21 consecutive patients undergoing elective laparoscopic cholecystectomy. After placement of an Eschmann tracheal tube with a printed intubation guide mark at the vocal cords, the distance was 28 (15) [5-54] mm (mean (SD) [range]). The tube was then repositioned so that the distance was 34 (3) [30-40] mm from tip of the tube to the carina. After creation of pneumoperitoneum, the distance was significantly decreased to 26 (5) [17-35] mm (p < 0.005), which was not significantly altered by subsequent moving of the patient to the reverse Trendelenburg and left lateral tilt position. The maximum distance of tube migration was 8 (4) [0-15] mm. Four out of 21 patients would have been at risk of bronchial intubation after pneumoperitoneum if the tube had not been repositioned. Placement of the tube according to the guide mark is not recommended for laparoscopic cholecystectomy.

Adult↗