Insulin up-regulates tumor necrosis factor-alpha production in macrophages through an extracellular-regulated kinase-dependent pathway

Hyperinsulinemia has recently been reported as a risk factor for atherosclerotic diseases such as coronary heart disease; however, the effect of insulin on the development of atherosclerosis is not well understood. Here we have investigated the direct effect of insulin on macrophages, which are known to be important in the atherosclerotic process. We treated THP-1 macrophages with insulin (10(-7) m) and examined the gene expression using nucleic acid array systems. The results of array analysis showed that insulin stimulated gene expression of tumor necrosis factor-alpha (TNF-alpha) the most among all genes in the analysis. In addition, insulin administration to macrophages enhanced both mRNA expression and protein secretion of TNF-alpha in a dose-dependent manner. To determine the signaling pathway involved in this TNF-alpha response to insulin, we pretreated the cells with three distinct protein kinase inhibitors: wortmannin, PD98059, and SB203580. Only PD98059, which inhibits extracellular signal-regulated kinases, suppressed insulin-induced production of TNF-alpha mRNA and protein in THP-1 macrophages. These observations indicate that insulin stimulates TNF-alpha production in macrophages by regulating the expression of TNF-alpha mRNA and that the extracellular signal-regulated kinase signaling pathway may have a critical role in stimulating the production of TNF-alpha in response to insulin in macrophages.

Hyperglycemia in diabetic rats reduces the glutathione content in the aortic tissue

The glutathione redox cycle plays a major role in scavenging hydrogen peroxide (H2O2) under physiological conditions. Recently, we demonstrated that a high glucose concentration in the culture medium reduced the level of H2O2 scavenging activity of human vascular smooth muscle cells (hVSMCs). We also showed that a high glucose concentration reduced the intracellular glutathione (GSH) content and the rate of uptake of cystine, which itself is a rate-limiting factor that maintains the GSH level (FEBS Lett.421: 19-22,1998). In the present study, we investigated whether the hyperglycemic condition in diabetic rats impairs the glutathione content in the aortic tissue in vivo. Wistar rats were divided into the following three groups: streptozotocin-induced diabetic rats (STZ-D, n=7), insulin-treated STZ-D rats (I-STZ-D, n=8), and non-diabetic controls (C, n=7). Fourteen days after streptozotocin injection, the aortic tissue was extracted and the GSH content in the aortic tissue was measured. Furthermore, the relationship between the GSH content in the aortic tissue and blood glucose level in Otsuka Long-Evans Tokushima Fatty (OLETF) rats aged 30 weeks, which developed diabetes spontaneously, was investigated. The GSH content in the aortic tissue of the STZ-D group (0.99+/-0.14 nmol/mg protein) was significantly lower than that of the control group (1.68+/-0.15 nmol/mg protein). Insulin treatment to the diabetic rats restored the GSH content in the aortic tissue (I-STZ-D group; 1.45+/-0.11 nmol/mg protein). Among the 22 Wistar rats, the GSH content in the aortic tissue was negatively correlated with the blood glucose level (r=-0.69, p<0.01, n=22). Among the OLETF rats, a similar negative correlation between the GSH content in the aortic tissue and blood glucose level was seen (r=-0.64, p<0.05, n=10). We demonstrated in vivo that the hyperglycemic condition in STZ-induced diabetic Wistar rats and OLETF rats reduced the GSH content in aortic tissue. This suggested reduced glutathione redox cycle function of aorta.

Acute effects of growth hormone on metabolism of pancreatic hormones, glucose and ketone bodies

Controversy exists as to whether acute administration of growth hormone has insulin-like effects. In conscious dogs, acute effects on plasma flows, plasma glucose, hepatic glucose output, free fatty acids, ketone bodies, insulin, and glucagon were determined following intravenous injection of 1 mg of growth hormone extracted from the canine pituitary gland. The following results were obtained: (1) Plasma flows in the portal vein, hepatic artery and hepatic vein were significantly increased 20 min after growth hormone administration. (2) By 40 min after growth hormone, the glucose concentration in these three vessels was significantly increased. (3) Hepatic glucose output was significantly increased 60 min after growth hormone administration. (4) Free fatty acids levels were significantly but transiently increased at 20 min, while ketone body concentrations were elevated at 120-180 min. (5) The insulin levels in the three vessels demonstrated a biphasic response. In the portal vein, they were significantly higher 20 min after growth hormone and again at 150-180 min. Glucagon concentrations were increased in all three vessels by 20 min and remained elevated for the remainder of the experiment. These results do not support an acute insulin-like action of growth hormone in normal dogs.

T cell receptor dynamism of mucosal and systemic CD4+ T cells in the course of an immune response to Escherichia coli heat-labile enterotoxin

The changes in T cell receptor (TCR) Vbeta expression, use, and clonality in mice orally challenged with Escherichia coli heat-labile enterotoxin (LT) were assessed. Use of the TCR Vbeta family and clonality were significantly changed at the single-cell level. In Peyer's patches of treated mice, use of TCR Vbeta6, Vbeta8, and Vbeta14 increased in CD4(+)CD44(+) T cells, compared with use in nontreated mice. On the other hand, use of TCR Vbeta1 and Vbeta8 was enhanced in splenic CD4(+)CD44(+) T cells. Intraepithelial lymphocytes isolated from LT-challenged mice showed expanded clonality (e.g., Vbeta1, Vbeta2, Vbeta9, and Vbeta18) and altered TCR Vbeta use (e.g., Vbeta15, Vbeta16, and Vbeta17). These findings reveal that oral administration of LT has distinct effects on mucosal versus systemic alphabeta T cells for induction of CD4(+) T cells with selected Vbeta use. This most likely reflects the function of LT as a mucosal modulator.

Addition of clonidine increases duration and magnitude of vasodilative effect induced by sympathetic block with mepivacaine in dogs

BACKGROUND AND OBJECTIVES

The aim of this study is to examine the duration and magnitude of vasodilative effect induced by sympathetic block with the addition of clonidine to mepivacaine.

METHODS

We measured mean arterial pressure (MAP), heart rate (HR), and right and left brachial artery blood flow (BABF) before and after stellate ganglion block (SGB) in dogs. The experimental protocol was designed as follows: (1) left SGB using 1.0 mL 0.5% mepivacaine (n = 6) and (2) left SGB using the addition of clonidine 0.5 microg to 1.0 mL 0.5% mepivacaine (n = 6).

RESULTS

MAP and HR did not change significantly throughout the study in either group. Left SGB with mepivacaine increased left BABF significantly from 10 minutes through 50 minutes after SGB (baseline, 100%; peak at 10 minutes after SGB, 176% +/- 28%; P <.01). Left SGB with the addition of clonidine to mepivacaine induced a significant increase of left BABF from 10 minutes through 70 minutes after SGB (baseline, 100%; peak at 10 minutes after SGB, 223% +/- 42%; P <.01). The values of left BABF after SGB with the addition of clonidine to mepivacaine were significantly higher than those of SGB with mepivacaine alone from 10 minutes through 80 minutes after SGB (P <.05). Right BABF decreased significantly after SGB throughout the study in both groups.

CONCLUSIONS

The addition of clonidine increases both duration and magnitude of the vasodilative effect induced by sympathetic block over that caused by mepivacaine alone.

[Anesthetic management of a patient with congenital antithrombin III Deficiency using temporal inferior vena cava filter]

We described the perioperative management of a patient with congenital antithrombin III deficiency using temporal inferior vena cava filter. A 30-year-old man with congenital antithrombin III deficiency was scheduled for artificial head replacement of the hip joint under general anesthesia. He was diagnosed as having congenital antithrombin III deficiency when he had had an episode of venous thrombosis after artificial head replacement of the right hip joint. He had been taking warfarin as an anticoagulant, and it was discontinued three days before surgery. To prevent perioperative thrombus formation, the plasma AT III activity was maintained above 80% before, during and after surgery using AT III concentrates. We also placed the temporal inferior vena cava filter. There was no serious thrombosis or embolism perioperatively. The use of the filter during the perioperative period helped to avoid development of serious thrombosis and embolism.

Enhancement of endothelial nitric oxide production by chenodeoxycholic acids in patients with hepatobiliary diseases

The purpose of this study was to clarify whether physiological concentrations of bile acids could affect endothelial nitric oxide production. We investigated the relationships between clinical concentrations of individual bile acids observed in patients with hepatobiliary diseases and endothelial nitric oxide production induced by each bile acid. Fifteen serum bile acids were measured using high-performance liquid chromatography combined with enzymatic fluorometry in 8 patients with liver cirrhosis, obstructive jaundice, and 8 healthy subjects. The effects of individual bile acids on nitric oxide production were examined in human umbilical endothelial cells by measuring the concentration of NO2- in the cultured medium. NO release in the blood was also determined by measuring the NO2-/NO3- concentration in these patients. In patients with hepatobiliary diseases, the plasma concentrations of chenodeoxycholic acid, ursodeoxycholic acid and cholic acid (free acid, taurine and glycine conjugates) were markedly elevated. Incubation of cells with chenodeoxycholic acid and deoxycholic acid (free acid, taurine and glycine conjugates) enhanced NO2- production in a concentration-dependent manner, while cholic acid (free and its conjugates) did not. The effects of individual bile acids on nitric oxide production were additive. Patients with liver cirrhosis and obstructive jaundice had higher plasma levels of NO2-/NO3- levels than the control subjects. These results suggest that increased plasma concentrations of chenodeoxycholic acid (free, taurine and glycine conjugates) in patients with hepatobiliary diseases may induce endothelial nitric oxide production. Thus, nitric oxide production induced by bile acids may be involved in the pathogenesis of circulatory abnormalities in patients with liver diseases.

[Anesthetic management of two patients with essential thrombocythemia]

We report different methods of anesthetic management in two patients with essential thrombocythemia. Case 1 is a 69-year-old male scheduled for cholecystectomy. His blood platelet counts were maintained between 10 to 40 x 10(4).microliters-1 after myelosuppression therapy. His preoperative blood tests were within normal limits. Since he had no signs of hemorrhage or thrombus preoperatively, an epidural catheter was inserted for intraoperative analgesia and postoperative pain relief. Anesthesia was induced with propofol and fentanyl, and maintained with N2O-O2-sevoflurane. Mepivacaine 1% was injected through the epidural catheter for intraoperative analgesia and buprenorphine was injected through the catheter for postoperative pain relief. His perioperative course was uneventful. Case 2 is an 88-year-old female scheduled for emergency enterectomy. She had had recurrent bouts of thrombosis. Her blood platelet counts were 89.1 x 10(4).microliters-1. Since her preoperative management of thrombocythemia had been poor, epidural anesthesia was not performed. Anesthesia was induced with propofol, and maintained with N2O-O2-sevoflurane. Her perioperative course was uneventful. We conclude that spinal or epidural anesthesia is not contraindicated when preoperative platelet counts and aggregation test are within normal limits in a patient with essential thrombocythemia.

Expression and characterization of a magnetosome-associated protein, TPR-containing MAM22, in Escherichia coli

A magnetosome-associated protein, MAM22, contains a TPR domain (five TPR motifs and one putative TPR motif) that has been known to mediate protein-protein interactions. We expressed the mam22 gene in Escherichia coli and found that the purified MAM22 was reversibly self-aggregated by NaCl. The structural model of MAM22 which has been proposed on the basis of the crystal structure of the N-terminal TPR domain of a human Ser/Thr protein phosphatase suggests the novel hydrophobic colloidal features of MAM22 with TPR motifs.

High-porosity expanded polytetrafluoroethylene grafts for thoracic vena cava replacement with or without an omentum wrap

We previously reported that, in a short-term thoracic inferior vena cava (IVC) replacement, a high-porosity expanded polytetrafluoroethylene (ePTFE) graft (fibril length 60 microm) performed well without altering the short-term patency, and that the healing of the high-porosity ePTFE graft was accelerated by an omentum wrap. The purpose of this study was to examine the long-term performance of the high-porosity ePTFE graft with or without an omentum wrap. Eighteen grafts were placed as a thoracic IVC replacement in dogs. Nine of the grafts were wrapped in an omental pedicle flap while the other 9 were not. At 1 month and 6 months, the grafts were harvested and examined for a pathological analysis. During the observation period, one dog died of a viral infection, while the other 17 dogs survived. At 1 month and 6 months, the patency rates of the 17 grafts were 100% regardless of the presence or absence of an omentum wrap. The healing of the grafts without omentum wrap was incomplete 6 months after implantation; granulation tissue was present in the center of the pseudointima. The grafts healed completely by the addition of an omentum wrap. Our data suggest that, with an omentum wrap, the high-porosity ePTFE graft is fully expected to show a good long-term function.

Neutralization of vascular endothelial growth factor prevents collagen-induced arthritis and ameliorates established disease in mice

Vascular endothelial growth factor (VEGF) is implicated in the pathogenesis of inflammatory joint diseases, including rheumatoid arthritis (RA). To determine the importance of this cytokine in vivo, the effect of administering VEGF-neutralizing antibodies to mice with collagen-induced arthritis (CIA), which has many immunological and pathological similarities to human RA, has been investigated. Either saline, normal rabbit immunoglobulin or anti-human VEGF121 rabbit polyclonal antibody was administered to mice subcutaneously either before the onset of arthritis or after the establishment of clinical disease. Anti-VEGF antibody administered prior to disease onset significantly delayed the development of arthritis and decreased clinical score and paw thickness as well as histological severity. On the other hand, the frequency of occurrence of disease compared to either the control group administered saline or normal rabbit immunoglobulin was not altered. Anti-VEGF antibody also significantly ameliorated clinical and histological parameters even when administered after disease onset. These results indicate a possible therapeutical potential for anti-VEGF treatment in human arthritis.

Enhancement of T helper2 response in the absence of interleukin (IL-)6; an inhibition of IL-4-mediated T helper2 cell differentiation by IL-6

Functional roles of interleukin (IL-)6 in T cell response were investigated. Mice deficient in IL-6 and wild mice were immunized with antigens (myelin oligodendrocyte glycoprotein or methylated BSA) and production of IL-4 and interferon (IFN)-gamma by regional lymph nodes was measured. IL-6 deficiency led to an enhancement of IL-4 and an inhibition of IFN-gamma production. Moreover, polyclonal stimulation of spleen T cells from unimmunized IL-6-deficient mice with anti-CD3 plus anti-CD28 antibodies (Abs) demonstrated an enhancement of T helper (Th)(2)responses. The presence of IL-6, however, augmented IL-4 production but it inhibited IFN-gamma expression by spleen T cells in response to polyclonal stimulation and by antigen-primed spleen T cells in response to re-challenge with the antigen. In contrast, the induction of spleen CD4-positive T cells into Th(2)cells in vitro by the anti-CD3 plus IL-4 was completely suppressed by exogenously added IL-6, whereas Th(1)differentiation of T cells by the anti-CD3 plus IL-12 was not inhibited by the presence of IL-6. Thus, these results indicate that IL-6 physiologically could modulate qualitative T cell response and suggest that it augments Th(1)responses partly through its inhibitory capability of IL-4-induced Th(2)differentiation of naive T cells.

Relative serum amyloid A (SAA) values: the influence of SAA1 genotypes and corticosteroid treatment in Japanese patients with rheumatoid arthritis

OBJECTIVES

(1) To determine whether serum concentration of serum amyloid A (SAA) protein is influenced by the SAA1 allele in Japanese patients with rheumatoid arthritis (RA) as previously shown in a healthy control group; and (2) to analyse what factors, based on such an allelic bias, influence the relative SAA values of those patients.

METHODS

SAA and C reactive protein (CRP) concentrations together with SAA1 genotypes were determined in 316 Japanese patients with RA. The relative SAA values were evaluated as an SAA/CRP ratio.

RESULTS

Comparison of the three SAA1 homozygote groups showed that the SAA/CRP ratio was highest in the 1.5/1.5 group (mean 9.0, p<0.01 v the other two homozygote groups) followed by the 1.3/1.3 group (mean 7.2, NS v the 1.1/1.1 group) and the 1.1/1.1 group (mean 4.0). The SAA/CRP ratio was significantly higher in patients receiving corticosteroids regardless of the presence of allele 1.5. No clear differences in the ratio between patients with or without amyloidosis were found.

CONCLUSION

The SAA1.5 allele and corticosteroid treatment had a positive influence on SAA concentrations in serum. These findings are important when evaluating SAA concentration in inflammatory diseases and when considering the cause or treatment of amyloidosis.

Pediatric caudal block with mepivacaine, bupivacaine or a mixture of both drugs: requirement for postoperative analgesia and plasma concentration of local anesthetics

STUDY OBJECTIVES

To assess the effects of pediatric caudal block using mepivacaine, bupivacaine, or a mixture of both drugs on postoperative analgesia, and to examine plasma concentrations of the local anesthetics after caudal injection.

DESIGN

Prospective, randomized, double-blind study.

SETTING

Operating room and pediatric surgical ward.

PATIENTS

60 ASA physical status I children weighing 10 to 20 kg (26 females, 34 males), and scheduled for inguinal herniorrhaphy.

INTERVENTIONS

Patients randomly received caudal block with 1 mL/kg of mepivacaine 1% (Group M, n = 20), 1 mL/kg of bupivacaine 0.25% (Group B, n = 20), or a mixture of 0.5 mL/kg of mepivacaine 1% and 0.5 mL/kg of bupivacaine 0.25% (Group MB, n = 20) after induction of anesthesia with sevoflurane in 50% oxygen (O2). Anesthesia was maintained with 66% nitrous oxide in O2 supplemented with sevoflurane at an end-tidal concentration of less than 1%.

MEASUREMENTS AND MAIN RESULTS

Postoperative pain scores using a pediatric pain scale and plasma concentration of each local anesthetic were measured. In Group M, four patients required postoperative analgesics within the first 24 hours. However, no patients required postoperative analgesics in Groups B and MB. In Group M, the plasma concentration of mepivacaine of two patients exceeded 5 microg/kg of the level of toxicity. However, these patients did not show any toxic symptoms. Because a mixture of two local anesthetics halves the concentration of each local anesthetic, the plasma concentrations of mepivacaine and bupivacaine in Group MB were significantly lower than those of Groups M and B.

CONCLUSIONS

Pediatric caudal block with a mixture of mepivacaine and bupivacaine is effective for intraoperative and postoperative analgesia.

Sertoli cells inhibited apoptosis of pachytene spermatocytes and round spermatids

Apoptosis in the testis represents an important physiological mechanism that regulates the number of germ cells in the seminiferous epithelium. This apoptosis is believed to be regulated by many factors, including growth factors and cytokines, which appear to suppress apoptosis of the germ cells. In this study, we examined the roles of Sertoli cells on the regulation of pachytene spermatocyte (PS) and round spermatid (RSd) apoptosis with either a co-culture trans-well system or a direct contact system. Apoptosis was detected by low molecular weight DNA fragmentation assay, in situ end labeling, and an LDH assay. In addition, the level of Bcl-2, Bax, and ICE mRNAs in PS and RSd by Northern blot analysis. When PS and RSd were cultured with Sertoli cells in either a trans-well system or direct contact system, the extent of apoptotic DNA fragmentation and LDH level were both significantly lower than those control values. TUNEL staining also revealed the inhibition of apoptosis of PS and RSd when they were cultured with Sertoli cells compared with controls (p <0.05). Moreover, the extent of apoptotic DNA fragmentation and LDH level were significantly lower in the direct contact system than in the trans-well system. TUNEL staining also demonstrated a more decrease in apoptosis of PS and RSd in the direct contact system compared with the trans-well system (p < 0.05). PS and RSd cultured with Sertoli cells exhibited an increase in Bcl-2 mRNA, whereas those cultured with serum-free medium did not show any change. The levels of Bax and ICE mRNAs decreased in PS and RSd cultured with Sertoli cells in comparison with control values. These results suggest that Sertoli cells can prevent apoptosis of germ cells, and that the effect of Sertoli cells on germ cells is mediated by cell to cell interaction or, remote effects of inhibitory factors on apoptosis.

Epizootic outbreaks of gizzard erosion associated with adenovirus infection in chickens

Two outbreaks of gizzard erosion in slaughtered broiler chickens in Japan were examined pathologically and microbiologically. The prevalences of such lesions were 9%-11% and 4%-50% in the affected flocks. Affected chickens had no clinical signs. Group I fowl adenovirus (FAV) serotype 1 was isolated from gizzard lesions. Histologically, gizzard mucosa were necrotic. Intranuclear inclusion bodies were seen in the enlarged nuclei of degenerating epithelial cells of the gizzard. The keratinoid layer in the erosion was edematous and desquamated and contained degenerative cells. Moderate to marked inflammatory cell infiltration was observed in the lamina propria and perivascular connective tissue in the submucosa and muscle layer. Immunohistochemical staining showed evidence of FAV antigens in the intranuclear inclusion bodies within degenerating epithelial cells. Ultrastructurally, numerous viral particles were demonstrated in the inclusions.

Hydroxyapatite-pulp composite fiber sheet bed: A new material for the immobilization of CHO-K1 cells

A new immobilization material for cell culture, ahydroxyapatite-pulp composite fiber (HAPC) sheet bed, was usedto grow CHO-K1 cells. The sheet bed for cell culture wasprepared from HAPC fiber by paper-making techniques. Scanning electron microscopic analysis revealed that the HAPCsheet bed had a structure consisting of piled fibers with spaces 10-200 mum in diameter and a pore surface area of 0.32 m(2) g(-1). Using a 25 x 25 mm(2) squareHAPC sheet bed 0.41 mm in thickness (85 g m(-2) basis weight) for cell culture, CHO-K1 cells grew to a cell densityof 3.7 x 10(7) cells cm(-3) in a 60 mm plastic dish over a 6-day culture period. High-density culture of CHO-K1 cells was successfully performed using the HAPC sheet bed in a 500 ml spinner flask over a 21-day culture period. The HAPC sheet bed, wound around the stirrer paddle, was rotated in the spinner flask in order to supply nutrientsand remove waste products efficiently. The HAPC sheet bedhas a large surface area to support cell growth and there islarge diffusion space inside of the bed. This newautoclavable substrate for anchorage-dependent cells can be easily scaled-up.

Experimental infection of specific-pathogen-free chickens with serotype-1 fowl adenovirus isolated from a broiler chicken with gizzard erosions

Gizzard lesions were formed in specific-pathogen-free (SPF) white leghorn chickens inoculated with fowl adenovirus (FAV). The virus, serotype 1 FAV 99ZH strain (FAV-99ZH), was originally isolated from the gizzard mucosa of commercial broiler chickens exhibiting gizzard erosion with intranuclear inclusion bodies. Five-day-old and 53-day-old SPF white leghorn chickens were inoculated with FAV-99ZH by both oral and ocular routes and then examined at necropsy on days 3, 5, 7, 10, 14, and 21 postinoculation (PI). There were no clinical signs in any of the chickens after the inoculation. Focal gizzard lesions occurred macroscopically, however, in inoculated chickens at several experimental periods. FAV was recovered from tissue samples of the proventriculus, gizzard, pancreas, and rectum by day 10 or 7 PI but was not recovered from liver samples of any of the chickens. These results indicate that FAV isolated from gizzard erosion is able to reproduce gizzard lesions as necrosis and erosion in SPF white leghorn chickens and that it may have a greater degree of tissue tropism in gizzards and other digestive organs than in the liver.

Acute cigarette smoking reduces vasodilative effect induced by sympathetic block in dogs

BACKGROUND AND OBJECTIVES

The aim of this study is to clarify the influence of acute cigarette smoking on vasodilation induced by sympathetic block.

METHODS

We measured mean arterial pressure, heart rate, left brachial artery blood flow (BABF), right femoral artery blood flow (FABF), and plasma catecholamines in dogs to examine the effect of acute cigarette smoking after stellate ganglion block (SGB). The experimental protocol was: (1) Left SGB using 1.0 mL 0.5% mepivacaine without smoking (sham smoking); and (2) left SGB using 1.0 mL 0.5% mepivacaine followed by a single cigarette smoking (nicotine 1 mg) 15 minutes after the block.

RESULTS

SGB induced a significant increase of BABF during the study (baseline, 100%; peak at 10 minutes after SGB, 176% +/- 9%; P <.05) in sham smoking and a significant decrease of FABF from 10 minutes after the block to 20 minutes after sham smoking (baseline, 100%; bottom at 5 minutes after sham smoking, 82% +/- 8%; P <.05). Smoking after SGB induced a significant decrease of BABF 60 minutes after smoking (baseline, 100%; 69% +/- 11%; P <.05) and a significant decrease of FABF during the study (baseline, 100%; bottom at 20 minutes after smoking, 74% +/- 20%; P <.05). Smoking significantly increased plasma norepinephrine and epinephrine through the study.

CONCLUSIONS

Sympathetic block induces a significant increase of peripheral blood flow, but smoking produces a significant decrease in the blood flow in the SGB-induced dilated vessels.

Osmolality dependence of erythrocyte sedimentation and aggregation in a strong magnetic field

In order to specify the major determinant of the magnetic enhancement of erythrocyte sedimentation observed previously, the dependence of erythrocyte sedimentation rate (ESR) on osmolality was measured under a strong magnetic field. Even at hypotonic osmolality, an increase in ESR due to aggregation was observed in plasma solution as compared with that without aggregation in saline solution. However, the magnetic field did not enhance ESR at hypotonic osmolality, when the cell shape was an isotropic sphere (spherocyte). Thus, we narrowed our search to a mechanism that would explain the enhanced ESR found specifically in anisotropic erythrocytes. It was concluded that the major determinant can only work for anisotropic erythrocytes and is a magnetic field-induced increase in an intermembrane adhesive area due to magnetic orientation of anisotropic erythrocytes.

[A case of ventricular tachycardia immediately after electroconvulsive therapy in a schinzophrenic patient]

A 33 year-old man weighting, 93 kg with schizophrenia underwent repeated electroconvulsive therapy (ECT) under general anesthesia with thiamylal 200 mg and suxamethonium 80 mg. On his fourth ECT, he developed ventricular tachycardia (VT) immediately after the treatment under general anesthesia with the same agents. The duration of VT was approximately 30 s. The VT returned to sinus rhythm without any special treatment. We speculate that light anesthesia with a small amount of thiopental associated with release of serum potassium caused by suxamethonium induced increased release of catecholamine by ECT to cause VT. After that incident, the patient underwent ECT six times under general anesthesia with thiamylal 250 mg and vecuronium 8 mg, in combination with preventive injection of magnesium sulfate 20 g without any cardiovascular complications. We conclude that the anesthetic management of patients undergoing ECT under general anesthesia should be paid a careful attention for cardiovascular instability, even if they do not have any heart diseases.

[Anesthetic experience of emergency coronary artery bypass graft operation in a patient with cardioamyloidosis]

A 76-year-old woman with acute myocardial infarction underwent an emergency coronary artery bypass graft operation. She developed cardiac failure and sick sinus syndrome before the surgery because she was with cardioamyloidosis. Therefore, intra-aortic balloon pumping and the pacemaker were used to maintain the hemodynamics prior to the operation. Anesthesia was induced with midazolam 5 mg, morphine 30 mg and pancuronium 5 mg, and maintained with 0.3-0.5% isoflurane in 50% nitrous oxide and 50% oxygen. Morphine 10 mg was also injected during the surgery, and the total dose of morphine 40 mg was administered. The pacemaker at 80 bpm was inserted and mexiletine 0.5 mg.kg-1.h-1 was given to prevent ventricular arrhythmias at weaning from cardio-pulmonary bypass. The surgical operation was successfully performed and the postoperative course was uneventful. A combination of light inhalation anesthesia with narcotics may be a choice for anesthetic management of patients with cardioamyloidosis as this method has less influence on hemodynamics.

High concentration sevoflurane induction of anesthesia accelerates onset of vecuronium neuromuscular blockade

PURPOSE

To investigate neuromuscular block using accelography after administration of vecuronium under sevoflurane 8% induction and maintenance with sevoflurane 2% in adults.

METHODS

Patients were allocated to three groups: (1) group I: anesthesia was induced and maintained with propofol and fentanyl (n= 15), (2) group II: anesthesia was induced with propofol and maintained with N2O(66%)-O2-sevoflurane 2% (n = 15), (3) group III: anesthesia was induced with sevoflurane 8% using a vital capacity inhalation induction and maintained with N2O(66%)-O2-sevoflurane 2% (n = 15). 0.1 mg x kg(-1) vecuronium was used for paralysis three minutes after anesthetic induction and reversed using intravenous 0.04 mg x kg(-1) neostigmine with 0.02 mg kg atropine when the train-of-four (TOF) ratio returned to 25%.

RESULTS

The onset time from initial administration of vecuronium to maximal block in the group III was shorter than that in the groups I and II (139 +/- 35, 193 +/- 35 and 188 +/- 47s, respectively: P < 0.05). The clinical duration from maximal block to 25% recovery of TOF ratio in group II and III was longer than that in the group I (47 +/- 15, 48 +/- 14 and 36 +/- 10 min, respectively: P < 0.05). The reversal times from administration of neostigmine to 75% of TOF ratio in groups II and III were longer than that in the group I (196 +/- 53, 208 +/- 64 and 136 +/- 28s, respectively: P < 0.05).

CONCLUSIONS

Vital capacity inhalation induction of anesthesia with sevoflurane accelerates onset and prolongs duration of vecuronium neuromuscular block compared with propofol-fentanyl anesthesia.

The expression of ion channel mRNAs in skeletal muscles from patients with myotonic muscular dystrophy

We investigated gene expression patterns of ion channels including the apamin-sensitive small-conductance Ca(2+)-activated K(+) (SK3) channel, the adult isoform of the skeletal muscle Na(+) channel (SkM1), the fetal isoform of skeletal muscle Na(+) channel (H1), and the Cl(-) channel (ClC-1) by using the semiquantitative reverse transcriptase-polymerase chain reaction (RT-PCR) for muscle samples from patients with adult onset myotonic dystrophy (DM), amyotrophic lateral sclerosis, and polymyositis. Patients with DM showed a significant increase in SK3 mRNA but not in mRNAs for other ion channels. The increased expression of SK3 gene in DM did not correlate with H1, the marker of muscle denervation, or the percentage of type 2C fiber, the marker of muscle regeneration.

Structure, expression, and conserved physical linkage of mouse testicular cell adhesion molecule-1 (TCAM-1) gene

Isolation and characterization were performed for cDNA encoding mouse testicular cell adhesion molecule-1 (TCAM-1) using 2908 bases coding for a protein having 548 amino acids (60 kDa). Mouse TCAM-1 protein was found to consist of seven domains for signal sequence, five immunoglobulin (Ig) domains, and the transmembrane plus cytoplasmic domain. TCAM-1 gene and the region linking it to growth hormone (GH) gene located downstream from the TCAM-1 gene were then analyzed. The mouse TCAM-1 gene was 11.6 kb in length with 8 exons; the same as for the 12.0 kb rat gene. The distance from the TCAM-1 to GH gene was 12.5 kb in the mouse genome, and 7.6 kb in the rat. By Northern hybridization, 3.1-kb TCAM-1 mRNA was detected in 17-day testis and would appear present in pachytene spermatocytes and round spermatids.

Induction of cyclooxygenase-2 in rat gastric mucosa by rebamipide, a mucoprotective agent

Recent studies indicate an expression of mitogen-inducible cyclooxygenase (COX-2) in gastric mucosa. Rebamipide, a mucoprotective agent enhances prostaglandin (PG) synthesis. The present study was designed to clarify the mechanism for rebamipide-induced mucosal protection. Male Sprague-Dawley rats were administered 5, 15, or 50 mg/kg/day rebamipide for 14 days. The expression of constitutive cyclooxygenase (COX-1) and COX-2 in gastric mucosa was determined using Western blot analysis. Another series of rats was used to examine 1) the levels of PGE(2) in stomach with and without pretreatment with a COX-2 inhibitor; 2) the protective action of rebamipide against gastric damage caused by 0.6 N HCl; and 3) the effects of a COX-2 inhibitor on rebamipide-induced gastric mucosal protection. COX-2 expression was enhanced, whereas COX-1 expression did not change significantly in the gastric mucosa of rats after treatment with rebamipide. The gastric mucosal PGE(2) was higher in the rebamipide groups than in the vehicle-treated group. Rebamipide also suppressed gastric damage induced by HCl in a dose-dependent manner. A COX-2 inhibitor blocked the rebamipide-induced increase in mucosal PGE(2), and mucosal protection induced by rebamipide. The results indicate that rebamipide induces COX-2 expression, increases PGE(2) levels, and enhances gastric mucosal defense in a COX-2-dependent manner. Thus, COX-2 has an important role in the effects of rebamipide on gastric mucosal protection.

Expression of cyclooxygenase-2 and nitrotyrosine in human gastric mucosa before and after Helicobacter pylori eradication

To determine whether cure of Helicobacter pylori infection influences the expression of COX-2 and nitrotyrosine in the distal stomach of humans, biopsy specimens were examined immunohistochemically. H. pylori infection was determined using a rapid urease test, culture and histology. Positive staining of COX-2/nitrotyrosine in the epithelium was expressed as the percentage of stained cells to the total epithelial cells. There was a significant increase in COX-2/nitrotyrosine staining in H. pylori -positive subjects compared with H. pylori -negative subjects. Cure of the infection resulted in a significant decrease in both COX-2/nitrotyrosine staining in all patients (52.1+/-12.1% vs 15. 4+/-7.2%, P<0.001; and 57.3+/-13.6% vs 36.1+/-18.0%, P<0.01, respectively). However, immunoreactivity of COX-2/nitrotyrosine was observed in all cases with intestinal metaplasia even after the cure of H. pylori infection.Thus, cure of H. pylori infection may decrease the risk of gastric carcinogenesis due to COX-2 and NO-related compounds in gastric mucosa but not in those patients with intestinal metaplasia.

Three cases of malignant pheochromocytoma treated with cyclophosphamide, vincristine, and dacarbazine combination chemotherapy and alpha-methyl-p-tyrosine to control hypercatecholaminemia

We describe 3 cases of malignant pheochromocytoma with multiple metastases which were treated with cyclophosphamide, vincristine and dacarbazine (CVD) combination chemotherapy and alpha-methyl-p-tyrosine. Case 1 was operated on first but hypercatecholaminemia could not be completely controlled. Cases 2 and 3 received chemotherapy, CVD combination chemotherapy and/ or alpha-methyltyrosine and good control of hypercatecholaminemia was attained. In all cases it was possible to control hypercatecholaminemia during most of the time they were administered a-methyltyrosine despite the presence of tumors. None of the patients suffered hypertension crises. In our patients treatment with CVD plus a-methyl-p-tyrosine proved to be safe and ameliorated the clinical course.

Airway obstruction during general anaesthesia in a child with congenital tracheomalacia

Fibreoptic bronchoscopy is often used to diagnose tracheomalacia under local anaesthesia. However, in children, general anaesthesia may be required due to difficulty in obtaining co-operation. A 1-yr-old girl with a suspected congenital tracheomalacia was scheduled for diagnostic fibreoptic bronchoscopy. During induction of anaesthesia by inhalation of increasing concentration of sevoflurane, spontaneous breathing became irregular and a partial airway obstruction occurred. Because vecuronium relieved the airway obstruction, the airway was managed using a laryngeal mask. No further airway obstruction occurred during fibrescopy under controlled ventilation, but when spontaneous breathing resumed, marked airway obstruction occurred. The trachea was intubated immediately. Caution is required to manage the airway without tracheal intubation during general anaesthesia in the patient with tracheomalacia.

[Pre-emptive analgesia with intravenous ketamine reduces postoperative pain in young patients after appendicectomy: a randomized control study]

Thirty-six young patients (12-17 years old) for appendicectomy were randomly allocated to receive ketamine 0.5 mg.kg-1 (K 0.5 group; n = 12), ketamine 1.0 mg.kg-1 (K 1.0 group; n = 12), or lactated Ringer's solution 5 ml (control group; n = 12), which was administered intravenously before incision. After the surgery, all patients received a nonsteroidal anti-inflammatory drug (NSAID) without limitation as requested by the patient. Pain scores at rest and on movement were assessed at 6-10 hr, 24 hr, and 48 hr post-operatively using a visual analogue scale. The frequency at which NSAID was given for postoperative analgesia in the first 48 hr after the surgery was recorded. The patients in the K 0.5 and K 1.0 groups had significantly lower pain scores at rest 6-10 hr postoperatively than the patients in the control group (P < 0.05). Additionally, the patients in the K 1.0 group had a significantly lower pain score on movement 6-10 and 48 hr postoperatively than those in the control group (P < 0.05). The K 0.5 and K 1.0 groups each used significantly less NSAID during the 48-hr postoperative period than the control group (P < 0.05). Intravenous administration of ketamine before incision was associated with decreases in pain at rest 6-10 hr postoperatively and a reduction in NSAID requirement after appendicectomy. Administration of ketamine 1.0 mg.kg-1 prior to incision was superior to administration of 0.5 mg.kg-1 in relief of pain on movement after the surgical procedure.

Propofol prevents lipid peroxidation following transient forebrain ischemia in gerbils

PURPOSE

To ascertain whether propofol prevents lipid peroxidation on delayed neuronal death induced by transient forebrain ischemia in the hippocampal CA1 subfield in gerbils.

METHODS

Forty gerbils were randomly assigned to five groups: Group I, control, sham operation treated with physiological saline solution (PSS); Group II, ischemia/reperfusion treated with PSS; Group III, ischemia/reperfusion treated with 50 mg x kg(-1) propofol; Group IV, ischemia/reperfusion treated with 100 mg x kg(-1) propofol; Group V, ischemia/reperfusion treated with 150 mg x kg(-1) propofol. Transient forebrain ischemia was induced by occluding the bilateral common carotid arteries for four minutes under N2O/O2/halothane anesthesia after propofol or PSS. Five days later, the cerebrum was removed and each forebrain was cut into two including the hippocampus. Lipid peroxidation was determined using the production of malondialdehyde (MDA), and histopathological changes in the hippocampal CA1 subfield were examined.

RESULTS

In group II, the pyramidal cells were atrophic and pycnotic; vacuolation and structural disruption of the radial striated zone was observed. In the other four groups, these changes were not observed. Degenerative ratios of pyramidal cells were: Group I: 4.9 +/- 2.3, Group II: 94.1 +/- 4.5 (P < 0.01), Group III: 12.5 +/- 5.7, Group IV: 11.0 +/- 4.6, Group V: 9.6 +/- 4.9%. Production of MDA was: Group I: 83 +/- 22, Group II: 198 +/- 25 (P < 0.01), Group III: 153 +/- 39, Group IV: 113 +/- 34, Group V: 106 +/- 27 nmol x g(-1) wet tissue.

CONCLUSION

Propofol attenuated delayed neuronal death by preventing lipid peroxidation induced by transient forebrain ischemia in the hippocampal CA1 subfield in gerbils.

Symptomatic improvement in dyspnea following tracheobronchial metallic stenting for malignant airway obstruction

PURPOSE

To investigate the value and limitation of Gianturco expandable metallic stenting for patients with dyspnea due to stenotic tracheobronchial lesions associated with malignancies.

MATERIAL AND METHODS

We treated 55 lesions of 44 patients with obstructing stenotic tracheobronchial lesions related to end-stage malignancies by Gianturco expandable metallic stents (EMSs).

RESULTS

In 42 of 44 patients, the dyspnea subjectively improved after the procedure (95.5%). An improvement over one grade of the Hugh-Jones classification was shown in 79.5% (35/44); in 80% (20 of 25 patients) with intraluminal tumor and in 78.9% (15 of 19 patients) with extrinsic compression. Seven of the 44 patients developed dyspnea related to re-stenosis of 10 lesions and 1 of these patients developed dyspnea related to re-re-stenosis during follow-up. The mean duration of survival was 4.3 months in patients who underwent stenting. No significant differences in survival rates and primary patency rates were seen in patients with extrinsic compression compared to patients with intraluminal tumors.

CONCLUSION

Gianturco EMS therapy was valuable in patients who suffered from dyspnea due to airway stenosis causing obstruction.

Creation of aortic dissection model in swine

The use of mongrel dogs for experimental purposes was recently restricted and this report presents the experience of creating an aortic dissection model in swine. All the swine in group 1 were anesthetized without pentobarbital and the descending aorta was side-clamped during the creation of the aortic dissection. The false lumen of the completed dissection was patent in the long term despite not having the anchoring suture that the previous canine model required to stabilize the opening of the entry tear. All the swine anesthetized with pentobarbital (ie, group 2) died of heart failure either during cross-clamping of the descending aorta or postoperative aortography. In conclusion, creation of a thoracic aortic dissection is possible in swine, but cross-clamping of the thoracic descending aorta and pentobarbital anesthesia should be avoided.

Proton magnetic resonance spectroscopy of a patient with Gerstmann-Straussler-Scheinker disease

A 23-year-old woman with Gerstmann-Straussler-Scheinker disease (GSS) was investigated by 1H-magnetic resonance spectroscopy (1H-MRS). She developed gait ataxic at 22 years. The diagnosis was confirmed by DNA analysis showing a proline-to-leucine point mutation at codon 102 of the prion protein. On 1H-MRS, she showed a remarkable reduction of the N-acetylaspartate/creatine ratio in the frontal lobe, cerebellar hemisphere and vermis and putamen. MRI revealed mild atrophy of the cerebellar hemispheres and vermis and cerebral cortex, but single-photon emission computed tomography (SPECT) with 99mHMPAO showed normal perfusion in the cerebellum. The imaging studies suggest that MRS might be superior to MRI or SPECT for detection of early neuronal degeneration.

[Comparison between total intravenous anesthesia and inhalation anesthesia in the surgery of acute cholecystitis]

We investigated retrospectively the influence of anesthetic methods on the intraoperative managements and postoperative outcomes in 26 patients receiving emergency or early surgery for acute cholecystitis. Fourteen of the 26 patients received total intravenous anesthesia with propofol, fentanyl, and ketamine (PFK group), while the remainder received nitrous oxide and isoflurane or sevoflurane anesthesia (GO group). There were no significant differences between the groups with respect to demographic data. We found no significant differences between the groups in duration of operation and anesthesia, the incidence of intraoperative hypotension, and the use of ephedrine and dopamine during induction and maintenance of anesthesia. After surgery, the PFK group had significantly earlier bowel function than the GO group, with earlier starting of oral intake (54.0 +/- 25.1 vs 89.3 +/- 31.9 hours after surgery; P = 0.026). These data suggest that total intravenous anesthesia by propofol, fentanyl, and ketamine may provide the earlier recovery of bowel function than inhaled anesthesia after emergency or early surgery for acute cholecystitis.

Intrathecal administration of neutralizing antibody against Fas ligand suppresses the progression of experimental autoimmune encephalomyelitis

A therapy aimed at blocking the Fas/Fas ligand (FasL) system was investigated using a relapsing form of experimental autoimmune encephalomyelitis (EAE) in mice, an animal model of multiple sclerosis (MS). Intracisternal administration of neutralizing antibody against FasL during the progression phase of EAE significantly reduced the severity of the disease with milder inflammation and myelin breakdown in the central nervous system (CNS). These results raised the possibility that the Fas/FasL system might contribute to tissue destruction in the CNS in the acute phase of EAE and that the intrathecal administration of neutralizing antibody against FasL may be beneficial for suppression of the acute phase of MS.

Bile acids increase intracellular Ca(2+) concentration and nitric oxide production in vascular endothelial cells

The effects of bile acids on intracellular Ca(2+) concentration [Ca(2+)](i) and nitric oxide production were investigated in vascular endothelial cells. Whole-cell patch clamp techniques and fluorescence measurements of [Ca(2+)](i) were applied in vascular endothelial cells obtained from human umbilical and calf aortic endothelial cells. Nitric oxide released was determined by measuring the concentration of NO(2)(-). Deoxycholic acid, chenodeoxycholic acid and the taurine conjugates increased [Ca(2+)](i) concentration-dependently, while cholic acid showed no significant effect. These effects resulted from the first mobilization of Ca(2+) from an inositol 1,4,5-triphosphate (IP(3))-sensitive store, which was released by ATP, then followed by Ca(2+) influx. Both bile acids and ATP induced the activation of Ca(2+)-dependent K(+) current. Oscillations of [Ca(2+)](i) were occasionally monitored with the Ca(2+)-dependent K(+) current in voltage-clamped cells and Ca(2+) measurements of single cells. The intracellular perfusion of heparin completely abolished the ATP effect, but failed to inhibit the bile acid effect. Deoxycholic acid and chenodeoxycholic acid enhanced NO(2)(-) production concentration-dependently, while cholic acid did not enhance it. The bile acids-induced nitric oxide production was suppressed by N(G)-nitro-L-arginine methyl ester, exclusion of extracellular Ca(2+) or N-(6-aminohexyl)-5-chloro-l-naphthalenesulphonamide hydrochloride (W-7) and calmidazolium, calmodulin inhibitors. These results provide novel evidence showing that bile acids increase [Ca(2+)](i) and subsequently nitric oxide production in vascular endothelial cells. The nitric oxide production induced by bile acids may be involved in the pathogenesis of circulatory abnormalities in liver diseases including cirrhosis.

[A case of acute urticaria from hydroxyzine hydrochloride used for preanesthetic medication]

We report a case of acute urticaria probably caused by hydroxyzine hydrochloride. A 66-year-old male was scheduled for cardiac cystectomy by thoracic endoscopy. The patient was premedicated with atropine and hydroxyzine intramuscularly 30 min before arrival in the operating room. Abrupt general exanthema was observed when intravenous infusion was started. Although his general condition was stable, the operation was postponed. Three days later, the skin test was performed using several drugs. Only hydroxyzine hydrochloride gave positive result. It is assumed that hydroxyzine hydrochloride may have caused his urticaria.

Enhanced graft healing of high-porosity expanded polytetrafluoroethylene grafts by covalent bonding of fibronectin

The effect of covalent bonding of fibronectin on the patency and graft healing of high-porosity expanded polytetrafluoroethylene (ePTFE) grafts was evaluated. Bilateral carotid grafting was performed in ten mongrel dogs using high-porosity (60 microm) ePTFE grafts, 4 cm in length and 4 mm in internal diameter, that either had been pretreated by the covalent bonding of fibronectin (fibronectin grafts) or were untreated (control grafts). The grafts were harvested 4 to 6 weeks after surgery and subjected to macroscopic and light-microscopic observations. There was no significant difference in patency between the fibronectin grafts and the control grafts with rates of 80% and 70%, respectively. The thrombus-free area score was significantly greater in the fibronectin grafts than in the control grafts, at 86.9% vs 34.0%. Furthermore, the pseudointima was better replaced by fibrous tissue in the fibronectin grafts than in the control grafts, being lined with a layer of endothelial-like cells. More transmural tissue ingrowth was evident in the fibronectin grafts than in the control grafts. The covalent bonding of fibronectin improves graft healing by stimulating transmural tissue ingrowth in high-porosity ePTFE grafts.