Effect of PSK on FOLFOX4-induced peripheral neuropathy and bone marrow suppression in patients with metastatic colorectal cancer

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Background: FOLFOX4 has been confirmed as an effective treatment for metastatic colorectal cancer and is used as a postoperative adjuvant therapy. However adverse effects such as cold-sensitive paresthesia and bone marrow suppression are common and may necessitate changes in chemotherapy regimen despite FOLFOX effectiveness. PSK, a polysaccharide derived from a species of mushroom, has been developed in Japan as an immune-enhancing agent and is widely used in patients with gastric, colorectal and pulmonary cancer. PSK has also been reported to decrease some adverse effects of chemotherapy.

Methods: FOLFOX4 combined with PSK was administered to patients with metastatic colorectal cancer and the results were evaluated. Eight cycles of FOLFOX4 and PSK (3.0 g/day, p.o.) were given to 25 patients with metastatic colorectal cancer (19 hepatic, 3 pulmonary and 3 peritoneal).

Results: No patients showed CR (complete response, 0%) while PR (partial response), SD (stable disease) and PD (progressive disease) were seen in 48%, 36% and 16% of patients, respectively. Response rate was 48% and disease control rate was 84%. Frequency of adverse effects was significantly lower than described in the published data. Grades 1 and 3 neutropenia occurred in 48% and 24% of patients, respectively; grades 1 and 3 nausea in 48% and 4%, respectively; and grades 1, 2 and 3 sensory neurotoxicity in 52%, 4% and 0%, respectively. No patient dropped out due to adverse effects in this study.

Conclusions: PSK plus FOLFOX4 seems as effective as FOLFOX4 monotherapy, and significantly less toxic. These results suggest that this combination therapy may be more effective when given for a longer period, with lower incidence of adverse effects.

No significant financial relationships to disclose.

Conformation of the calmodulin-binding domain of metabotropic glutamate receptor subtype 7 and its interaction with calmodulin

Calmodulin (CaM), a Ca(2+)-binding protein, is a well-known regulator of various cellular functions. One of the targets of CaM is metabotropic glutamate receptor 7 (mGluR7), which serves as a low-pass filter for glutamate in the pre-synaptic terminal to regulate neurotransmission. Surface plasmon resonance (SPR), circular dichroism (CD) spectroscopy and nuclear magnetic spectroscopy (NMR) were performed to study the structure of the peptides corresponding to the CaM-binding domain of mGluR7 and their interaction with CaM. Unlike well-known CaM-binding peptides, mGluR7 has a random coil structure even in the presence of trifluoroethanol. Moreover, NMR data suggested that the complex between Ca(2+)/CaM and the mGluR7 peptide has multiple conformations. The mGluR7 peptide has been found to interact with CaM even in the absence of Ca(2+), and the binding is directed toward the C-domain of apo-CaM rather than the N-domain. We propose a possible mechanism for the activation of mGluR7 by CaM. A pre-binding occurs between apo-CaM and mGluR7 in the resting state of cells. Then, the Ca(2+)/CaM-mGluR7 complex is formed once Ca(2+) influx occurs. The weak interaction at lower Ca(2+) concentrations is likely to bind CaM to mGluR7 for the fast complex formation in response to the elevation of Ca(2+) concentration.

Glycation and phosphorylation of alpha-lactalbumin by dry heating: effect on protein structure and physiological functions

Alpha-lactalbumin (alpha-LA) was glycated with maltopentaose (MP) through the Maillard reaction (MP-alpha-LA) and subsequently phosphorylated by dry heating in the presence of pyrophosphate to investigate its structure and physiological functions. Glycation occurred effectively, and the sugar content of alpha-LA increased by approximately 22.3% through the Maillard reaction. The phosphorylation of MP-alpha-LA was enhanced with an increase in the dry-heating time from 1 to 5 d, and the phosphorous content of MP-alpha-LA increased by approximately 1.01% by dry heating at pH 4.0 and 85 degrees C for 5 d in the presence of pyrophosphate. The electrophoretic mobility of alpha-LA increased with an increase in the phosphorylation level. The circular dichroism spectra showed that the change in the secondary structure of the alpha-LA molecule by glycation and subsequent phosphorylation was slight. However, the Trp fluorescence intensity was increased by phosphorylation after glycation. In addition, the differential scanning calorimetry thermograms of alpha-LA showed that the denaturation temperature of MP-alpha-LA was decreased by phosphorylation. These results indicated that molten (partially unfolded) conformations of alpha-LA were formed by dry heating in the presence of pyrophosphate after glycation. The anti-alpha-LA antibody response was significantly reduced by glycation and subsequent phosphorylation. The suppressive effect of alpha-LA on the production of proinflammatory cytokines such as IL-6 and tumor necrosis factor-alpha from THP-1 cells after stimulation with lipopolysaccharide was significantly enhanced by glycation with MP and was further enhanced by phosphorylation after glycation. The Ca phosphate-solubilizing ability of alpha-LA was enhanced by phosphorylation. The apoptotic activity of alpha-LA was reduced by glycation and subsequent phosphorylation. These results suggest that phosphorylation by dry heating in the presence of pyrophosphate after glycation with MP through the Maillard reaction is a useful method for improvement of the physiological functions of alpha-LA.

[Repair of paravalvular leak after a third mitral valve replacement]

This study reports on a 57-year-old woman who underwent a 3rd mitral valve replacement and presented with complaints of fatigue. Laboratory examination revealed severe hemolytic anemia, and trans-esophageal echocardiography revealed a paravalvular leak (PVL) around the prosthetic valve at the posterior trigone in the mitral position. PVL was regarded as the cause of hemolytic anemia. At surgery, a small tissue defect was detected around the calcified posterior trigone of the mitral annulus with no evidence of infective endocarditis. The mitral PVL was successfully repaired with suture closure of the annular defect. The postoperative course was uneventful: postoperative echocardiography revealed no evidence of PVL, and the hemolytic anemia subsided.

Characterization of virus-induced gene silencing in tobacco plants infected with apple latent spherical virus

Apple latent spherical virus (ALSV) expressing green fluorescent protein (GFP-ALSV) was used for analysis of virus-induced gene silencing (VIGS) in tobacco plants expressing GFP (GFP-tobacco). In GFP-tobacco inoculated with GFP-ALSV, small dark spots appeared on inoculated leaves at 5 days post-inoculation (dpi), then expanded, and finally covered the whole area of the leaves after 12 dpi. Most of the fluorescence of upper leaves above the 12th true leaf disappeared at 21 dpi. Thus, GFP-ALSV infection efficiently triggered VIGS of a transgene (GFP gene) in tobacco plants. Analysis of GFP-silenced leaves showed that viral RNAs and proteins accumulated in all leaves where most GFP mRNA had been degraded. The siRNAs derived from ALSV-RNAs were not detected in samples from which siRNA of GFP mRNA could be easily detected. Direct tissue blot analysis showed that the spread of GFP-ALSV always preceded the induction of VIGS in infected leaves of GFP-tobacco. GFP leaf patch tests using Nicotiana benthamiana line 16c showed that Vp20, one of the three capsid proteins, is a silencing suppressor which interferes with systemic silencing.

Interaction of influenza virus fusion peptide with lipid membranes: effect of lysolipid

The effect of lysophosphatidylcholine (LPC) on lipid vesicle fusion and leakage induced by influenza virus fusion peptides and the peptide interaction with lipid membranes were studied by using fluorescence spectroscopy and monolayer surface tension measurements. It was confirmed that the wild-type fusion peptide-induced vesicle fusion rate increased several-fold between pH 7 and 5, unlike a mutated peptide, in which valine residues were substituted for glutamic acid residues at positions 11 and 15. This mutated peptide exhibited a much greater ability to induce lipid vesicle fusion and leakage but in a less pH-dependent manner compared to the wild-type fusion peptide. The peptide-induced vesicle fusion and leakage were well correlated with the degree of interaction of these peptides with lipid membranes, as deduced from the rotational correlation time obtained for the peptide tryptophan fluorescence. Both vesicle fusion and leakage induced by the peptides were suppressed by LPC incorporated into lipid vesicle membranes in a concentration-dependent manner. The rotational correlation time associated with the peptide's tryptophan residue, which interacts with lipid membranes containing up to 25 mole % LPC, was virtually the same compared to lipid membranes without LPC, indicating that LPC-incorporated membrane did not affect the peptide interaction with the membrane. The adsorption of peptide onto a lipid monolayer also showed that the presence of LPC did not affect peptide adsorption.

[Ascending aortic aneurysm following aortic valve replacement due to aortitis syndrome; report of a case]

A 60-year-old woman had previously undergone aortic valve replacement for aortic regurgitation. As the aortic wall was elastic hard, inflammatory change was suspected; therefore, we undertook a partial biopsy of the ascending aortic wall and the intraoperative pathological specimens were compatible with aortitis syndrome. As there was no active inflammatory change, she was diagnosed as inactive aortitis syndrome and steroid therapy was not applied. Seven years later, a follow-up computed tomography (CT) showed an ascending aortic aneurysm of 65 mm in diameter. Aortic root replacement was planned based on a clinical diagnosis of an aneurysm of the ascending aorta. The patient was discharged without complication 21 days after surgery. It is possible that an inactive stage of aortitis may lead to late dilatation of the ascending aorta; therefore, careful postoperative follow-up is necessary in such cases.

Colonic J-pouch decreases bowel frequency by improving the evacuation ratio

BACKGROUND/AIMS

To compare the functional outcome of ultra-low anterior resection for rectal cancer with colonic J-pouch reconstruction with that of straight reconstruction.

METHODOLOGY

Twenty-three patients who underwent ultra-low anterior resection with or without J-pouch reconstruction underwent bowel transit study, videodefecography, and answered a questionnaire survey 4 months and 1 year after surgery. Eleven healthy subjects underwent similar testing as controls.

RESULTS

Patients with a J-pouch had less frequent stools than patients with straight reconstruction 4 months after surgery (p<0.05), but the two groups were similar at 1 year. Bowel transit time was similar at both study points. The evacuation ratio was higher after J-pouch than straight reconstruction 4 months after surgery (p<0.05). However, the ratio improved in the straight group, and no difference existed at 1 year. Colonic contraction was seen only near the anastomosis 4 months after surgery, but the contraction proximal to the anastomosis improved over the next 8 months.

CONCLUSIONS

J-pouch reconstruction facilitates evacuation by improving the evacuation ratio. Although straight anastomosis caused excessive stool frequency 4 months after surgery, colonic function continued to improve and was comparable with J-pouch and straight reconstruction 1 year after surgery because the contraction ratio proximal to the anastomosis improved.

[Surgical fixation of the ribs for flail chest injuries]

The record of 20 patients presenting with flail chest injury from 1998 to 2005 was reviewed to determine surgical indication and timing. There were 4 groups with each indication as followed: 1) 8 patients with surgical indication for injury regions other than fractured ribs, 2) 5 without improvement of flail chest after internal pneumatic stabilization for more than 10 days, 3) 4 performed surgical fixation positively for flail chest with respiratory failure, 4) 3 with strong deformation of the thorax without respiratory failure. Eight patients (40%) required artificial respiration for more than 6 days after surgical stabilization. The reasons of prolonged artificial respiration included unconsciousness in 4 patients, pneumonia in 2, and others in 2. In the group consisting of 8 patients taking more than 6 days to be extubated after surgical fixation, the injury severity score (ISS) was significantly higher (p = 0.006) than that of the other group. In patients with no improvement of flail chest after internal pneumatic stabilization for more than 10 days, surgical fixation reduces the period of internal pneumatic stabilization and the risk of pneumonia. For the elderly who can develop complications easily, early indication of surgical fixation should be considered. In patients with unconsciousness or ISS > or = 25, the extubation delays frequently after surgical fixations.

[Cardiac papillary fibroelastomas: report of 2 cases]

We report 2 cases of cardiac papillary fibroelastomas in adults. Case 1: A 61-year-old man was admitted because echocardiography showed a 1 cm pedunculated papillary tumor in the left atrium. In an operation, it was located in the left atrium near the mitral valve and was resected along with a 5 mm margin of endocardium. Case 2: A 60-year-old woman had a 1 cm mobile tumor in the right ventricle near the tricuspid valve located by echocardiography in a preoperative examination of a ventricular septal defect. In an operation, a pedunculated tumor located in the right ventricle was resected. In these 2 cases, histopathology showed the tumor to be a papillary fibroelastoma. Almost all cardiac papillary fibroelastoma are closely related to the cardiac valve, but in these cases, the tumors were located in the left atrium, and the right ventricle, respectively, which is quite rare.

Improvement of Functional Properties of Whey Protein Isolate Through Glycation and Phosphorylation by Dry Heating

Whey protein isolate (WPI) was glycated with maltopentaose (MP) through the Maillard reaction, and the MP-conjugated WPI (MP-WPI) was then phosphorylated by dry heating in the presence of pyrophosphate. Glycation occurred efficiently, and the sugar content of WPI increased approximately 19.9% through the Maillard reaction. The phosphorylation of MP-WPI was enhanced with an increase in the dry-heating time from 1 to 5 d, and the phosphorus content of WPI increased approximately 1.05% by dry heating at pH 4.0 and 85 degrees C for 5 d in the presence of pyrophosphate. The electrophoretic mobility of WPI increased with an increase in the phosphorylation level. The stability of WPI against heat-induced insolubility at pH 7.0 was improved by conjugation with MP alone, and further improved by phosphorylation. Although the emulsifying activity of WPI was barely affected by glycation and phosphorylation, the emulsifying stability of phosphorylated MP-WPI (5 d), was 2.2 times higher than that of MP-WPI. Gelling properties such as hardness, resiliency, and water-holding capacity of heat-induced WPI gel were markedly improved, and the gel was rendered transparent by phosphorylation. The calcium phosphate-solubilizing ability of WPI was enhanced by phosphorylation. These results suggested that phosphorylation by dry heating in the presence of pyrophosphate after conjugation with MP is a useful method for improving the functional properties of WPI.

Effects of temperature on viral glycoprotein mobility and a possible role of internal "viroskeleton" proteins in Sendai virus fusion

The effect of temperature on fusion of Sendai virus with target membranes and mobility of the viral glycoproteins was studied with fluorescence methods. When intact virus was used, the fusion threshold temperature (20-22 degrees C) was not altered regardless of the different types of target membranes. Viral glycoprotein mobility in the intact virus increased with temperature, particularly sharply at the fusion threshold temperature. This effect was suppressed by the presence of erythrocyte ghosts and/or dextran sulfate in the virus suspension. In these cases also, no change in the fusion threshold temperature was observed. On the other hand, reconstituted viral envelopes (virosomes) bearing viral glycoproteins but lacking matrix proteins were capable of fusing with erythrocyte ghosts even at temperatures lower than the fusion threshold temperature and no fusion threshold temperature was observed over the range of 10-40 degrees C. The mobility of viral glycoproteins on virosomes was much greater and virtually temperature-independent. The intact virus treated with an actin-affector, jasplakinolide, reduced the extent of fusion with erythrocyte ghosts and the mobility of viral glycoproteins, while the treatment of virosomes with the same drug did not affect the extent of fusion of virosomes with erythrocyte ghosts and the mobility of the glycoproteins. These results suggest that viral matrix proteins including actins affect viral glycoprotein mobility and may be responsible for the temperature threshold phenomenon observed in Sendai virus fusion.

[Spinal cord ischemia after surgery for arch and aortic valve replacement with elephant trunk for plural thoracic aneurysms]

A 62-years old man had plural aneurysms from the aortic arch to the descending aorta. Y-grafting had been performed twice for an abdominal aortic aneurysm. We performed the first operation which involved aortic valve and arch replacement under deep hypothermia with selective cerebral perfusion. During the operation, hemodynamics was stable, but after the operation he developed paraplegia due to ischemic change in the spinal cord. It was considered that the cause of the ischemia might have been the changing of the blood supply to the spinal cord. In patients with severe atherosclerosis, the blood supply for the spinal cord needs to be very strictly determined.

[Sinus of Valsalva dilatation after replacement of the ascending aorta and aortic valve]

A 52-year-old woman, height, 149 cm; weight, 40 kg, was admitted because of anterior chest discomfort and palpitations. There was no family history of Marfan syndrome. She had undergone replacement of the ascending aorta and aortic valve 10 years prior for DeBakey II aortic dissection. Postoperative pathological examination of the resected aortic wall revealed cystic medionecrosis. Computed tomography(CT) 4 years after the surgery showed moderate enlargement of the preserved sinuses of Valsalva, and CT 10 years after the surgery showed enlargement of the sinus. She consented to a reoperation. The prostheses were explanted, and the aortic root was replaced with a composite graft. The right coronary artery ostium was completely closed, and no graftable portions of the distal right coronary artery were detected. Thus, the left coronary artery alone was reimplanted. The patient required extracorporeal membrane oxygenation for 10 days postoperatively, after which she recovered fully without complications. This case may indicate that the complete aortic root should be replaced during initial surgery of the ascending aorta or aortic valve in patients with potential risk of sinus of Valsalva dilatation.

Fusion, leakage and surface hydrophobicity of vesicles containing phosphoinositides: influence of steric and electrostatic effects

Calcium and lanthanum ion-induced fusion of lipid vesicles containing phosphatidylinositol (PI), phosphatidylinositol-4-monophosphate (PIP), phosphatidylinositol-4,5-bisphosphate (PIP2) or phosphatidylinositol-3,4,5-trisphosphate (PIP3) and its associated membrane properties, e.g., surface dielectric constant and vesicle leakage, were studied by fluorescence methods. The presence of poly-phosphorylated phosphoinositides (PPI) in lipid vesicles enhanced fusion, depending on the PPI phosphorylation level and the PPI concentration, as determined by the lipid mixing assay. This correlation held even at physiologically relevant small concentrations of PPI in vesicle membranes. However, the presence of nonphosphorylated PI inhibited fusion due to the steric effect of the inositol ring. The cation threshold concentration for the lipid mixing of vesicles made of mixtures of phosphatidylserine (PS) with PI increased with increasing PI contents. For all vesicle systems studied, a decrease in vesicle surface dielectric constant and an increase in vesicle leakage accompanied fusion. The presence of the nonphosphorylated inositol ring in PI did not interfere with the changes in the surface dielectric constant caused by fusogenic cations. Therefore, we deduce that the reduction of the surface dielectric constant is a necessary condition for membrane fusion to occur but it does not correlate with membrane fusion when interacting membranes are blocked for close approach as by the nonphosphorylated inositol ring.

[Coronary artery bypass grafting in octogenarian]

Coronary artery bypass graftings (CABG) in elderly patients are increasing in recent years. Several studies have shown that the rate of complications and mortality is higher in elderly patients than in younger ones. This report presents results of CABG in octogenarians. From January 1996 to December 1999, 362 patients underwent isolated CABG, of whom 15 were over 80 years old (80-year group) and 122 were 70-79 years old (70-year group). Preoperative cardiac function was worse in the 80-year group than in 70-year group [60% vs 29% in Canadian Cardiovascular Society (CCS) class III or IV]. No significant difference was found between two groups in extracorporeal circulation time, aortic clamp time, the number of bypasses and postoperative complications. We conclude that CABG should not be excluded in octogenarians because of their chronological age alone.

Peripheral pulmonary atelectasis and oxygentation impairment following coronary artery bypass grafting

BACKGROUND

Severe pulmonary oxygenation impairment occurred in some patients with pleurotomy during the harvest of the internal mammary artery graft followed by coronary artery bypass grafting (CABG). Peripheral pulmonary atelectasis in the postoperative chest X-ray was detected in these patients. We studied the efficacy of intraoperative positive end-expiratory airway pressure (PEEP) therapy for the prevention of postoperative pulmonary oxygenation impairment.

METHODS

The pleural cavity was intraoperatively opened in 40 patients with solitary CABG procedure performed during 5 years since January 1992. These patients were divided into two groups. Intraoperative PEEP therapy, which is initiated just after pleurotomy, was not used in 32 patients before May, 1996 (control group) and used for recent 8 patients with pleurotomy (PEEP group). The mean age of patients was 60 years old in the control group and 68 in the PEEP group.

RESULTS

Respiratory insufficiency (A-aDO2 >400 mmHg and RI >1.5) was detected in 6 patients in the control group. Three out of these 6 patients required long-term mechanical respiratory support over a week. No respiratory insufficiency occurred in patients of the PEEP group. Values of PaO2, A-aDO2, respiratory index and shunt ratio were significantly worse in the control group than in the PEEP group.

CONCLUSIONS

In conclusion, PEEP therapy may prevent pulmonary atelectasis and oxygen impairment after CABG.

Lung impairment following cardiac surgery in patients with pulmonary hypertension

BACKGROUND

Postoperative respiratory management following cardiac surgery is sometimes troublesome in patients with pulmonary hypertension. We retrospectively studied the relationship between the etiology of preoperative pulmonary hypertension and the postoperative decline of blood oxygenation capacity by focusing on the postoperative intravascular fluid volume.

METHODS

Sixteen adult patients with an atrial septal defect (preload group) and 17 patients with solitary mitral valve disease (afterload group) were studied. The mean age of the patients in the preload and afterload group was 51 and 52 years old, respectively.

RESULTS

Preoperative pulmonary-systemic pressure ratio and pulmonary artery resistance index were significantly higher in the preload group than in the afterload group. The respiratory index (RI) and the pulmonary shunt ratio (Qs/Qt) measured immediately after the operation was larger in the afterload group than in the preload group. Postoperative RI and Qs/Qt remained high until postoperative day 3 in both groups. In the preload group RI on postoperative day 1 had a reverse correlation with the central venous pressure (CVP). Meanwhile, the RI in the afterload group on postoperative day 1 was slightly larger in patients with a high CVP and pulmonary capillary wedged pressure. Similar relationships were seen in the relations between pulmonary capillary wedged pressure and RI in the afterload group. CONCLUSIONS In conclusion, a preoperative pulmonary vascular change and a postoperative precipitous decrease of pulmonary blood flow may have caused postoperative lung oxygenation impairment in the preload group. An extended period of extracorporeal circulation associated with cardiac arrest and postoperative volume overload may have caused lung impairment in the afterload group. In aspect of postoperative management, low CVP is beneficial to the patients in the afterload group, however, hypovolemia should be avoided in patients of the preload group.

Solution NMR structure of the myosin phosphatase inhibitor protein CPI-17 shows phosphorylation-induced conformational changes responsible for activation

Contractility of vascular smooth muscle depends on phosphorylation of myosin light chains, and is modulated by hormonal control of myosin phosphatase activity. Signaling pathways activate kinases such as PKC or Rho-dependent kinases that phosphorylate the myosin phosphatase inhibitor protein called CPI-17. Phosphorylation of CPI-17 at Thr38 enhances its inhibitory potency 1000-fold, creating a molecular on/off switch for regulating contraction. We report the solution NMR structure of the CPI-17 inhibitory domain (residues 35-120), which retains the signature biological properties of the full-length protein. The final ensemble of 20 sets of NMR coordinates overlaid onto their mean structure with r.m.s.d. values of 0.84(+/-0.22) A for the backbone atoms. The protein forms a novel four-helix, V-shaped bundle comprised of a central anti-parallel helix pair (B/C helices) flanked by two large spiral loops formed by the N and C termini that are held together by another anti-parallel helix pair (A/D helices) stabilized by intercalated aromatic and aliphatic side-chains. Chemical shift perturbations indicated that phosphorylation of Thr38 induces a conformational change involving displacement of helix A, without significant movement of the other three helices. This conformational change seems to flex one arm of the molecule, thereby exposing new surfaces of the helix A and the nearby phosphorylation loop to form specific interactions with the catalytic site of the phosphatase. This phosphorylation-dependent conformational change offers new structural insights toward understanding the specificity of CPI-17 for myosin phosphatase and its function as a molecular switch.

Smooth muscle cell proliferation at the vascular anastomotic stricture in rat aortotomy model

BACKGROUND

We recently suggested that a rat aortotomy model could be substituted for a vascular anastomotic stricture around a suture line. The aim of this study was to verify such a rat aortotomy model using proliferating cell nuclear antigen (PCNA) immunohistochemistry, which is a sensitive method for detection of proliferating cells in vascular tissue after injury.

METHODS

Longitudinal aortotomy was performed in the abdominal aorta of the rat subjects. The rats were sacrificed at 1, 2, 4 and 8 weeks following aortotomy (n=20 in each group). The control rats were sacrificed without aortotomy (n=20). The percentage of the lumen occluded by intimal thickening (I/M ratio) was calculated. All tissues were stained with antibodies against proliferating cell nuclear antigen (PCNA).

RESULTS

Values of I/M ratio were 8.5+/-4.4%, 15.6+/-9.5%, 11.8+/-5.5%, 9.6+/-6.2% at 1, 2, 4, 8 weeks following aortotomy in the injured groups and 0.4+/-0.1% in the controls, respectively. Those values in the injured group increased significantly as compared to the controls. There were also significant differences between one week and two weeks following aortotomy. The PCNA labeling index at one week following aortotomy (21.4+/-2.7%) was significantly higher than at two weeks following aortotomy (2.8+/-1.9%). SMCs in the intima at four and eight weeks following aortotomy were completely negative for PCNA.

CONCLUSIONS

The experimental rat aortotomy model was determined to be useful in the investigation of intimal thickening around the suture line.

Reconstruction of heavily calcified aorta and its visceral branches without extracorporeal circulation

A 61-year-old Japanese female was referred to our hospital for surgical treatment of a localized heavily calcified abdominal aorta. Preoperative angiograms and computed tomograms revealed severe stenosis of the aorta, resembling a slit. Bypass grafting between the thoracic and abdominal aorta was successfully performed together with the reconstruction of the celiac artery, superior mesenteric artery, and bilateral renal arteries without extracorporeal circulation. Postoperative angiograms showed patency of the graft and branches. A localized heavily calcified abdominal aorta is relatively rare, and the cause of this entity might be Takayasu's aortitis.

A highly selective inhibitor of Rho-associated coiled-coil forming protein kinase, Y-27632, prolongs cardiac allograft survival of the BALB/c-to-C3H/He mouse model

BACKGROUND

Current studies provide evidence that a small G protein, RhoAp21, and its target protein, Rho-associated coiled-coil forming protein kinase (ROCK), regulate not only cell shape but also cell migration. However, contribution of Rho/ROCK signaling to graft rejection is unknown. The purpose of this study was to evaluate the inhibitory effect of Y-27632, a highly selective ROCK inhibitor, on rejection of heterotopic cardiac transplantation in mice.

METHODS

BALB/c (H-2(d)) hearts were transplanted into C3H/He (H-2(k)) as allografts that were full histoincompatibility combinations. The recipients received several doses of Y-27632, commencing 1 day before cardiac transplantation until rejection. We used immunohistochemical study to detect the expression of myocardial intercellular adhesion molecule 1 (ICAM-1) and vascular cell adhesion molecule 1 (VCAM-1), and we immunoenzymatically measured serum interleukin (IL)-6. Furthermore, we evaluated cardiac allograft vasculopathy treated with either FK506 or Y-27632 at Day 100.

RESULTS

The Y-27632-treated (2 mg/kg/day) allografts prolonged the mean survival time (49.6 +/- 10.1 days, n = 12) as compared with the untreated allografts (8.1 +/- 0.4 days, n = 7, p < 0.001). Histologic examinations of the Y-27632-treated allografts at Day 7 showed greatly reduced leukocyte infiltration compared with the untreated allografts. The Y-27632-treated allografts revealed faint expression of myocardial ICAM-1 and VCAM-1 at Day 7. The serum IL-6 levels also decreased in the Y-27632-treated mice. In the long-surviving Y-27632-treated allografts at Day 100, we saw neither active rejection nor apparent thickening of vascular intima.

CONCLUSION

Our results suggest that ROCK plays a major role in cardiac rejection in the BALB/c-to-C3H/He mouse model. Inhibition of this Rho/ROCK signaling may be an alternative therapeutic option for managing acute and chronic rejection.

[Clinical experience of intermittent administration of 5-FU and CDDP to patients with advanced and recurrent gastric cancer]

We administered 5-FU and CDDP (FP) intermittently to four patients with advanced and recurrent gastric cancer. A minor response (MR) and partial response (PR) were achieved in two of four patients who had evaluable lesions for this treatment, and few side effects were observed. Only one patient among six showed grade 2 leucocytopenia after 15 administrations of this chemotherapy, when she had attained a partial response in a lung metastasis. The other patients had no side effects such as bone marrow suppression or digestive symptoms. This intermittent FP treatment may be an effective and promising therapy with few side effects even for the patients with serious conditions.

Photosynthetic electron transport inhibition by pyrimidines and pyridines substituted with benzylamino, methyl and trifluoromethyl groups

The decrease of the number of ring nitrogen atoms of 2-benzylamino-4-methyl-6-trifluoromethyl-1,3,5-triazines on herbicidal activity and inhibition of photosynthetic electron transport (PET) was assayed using thylakoids from Spinacia oleracea or atrazine-resistant Chenopodium album. Three 2-benzylamino-4-methyl-6-trifluoromethyl-1,3,5-triazines, nine pyrimidines with a benzylamino-, methyl- and trifluoromethyl-group, 2-benzylamino-6-methyl-4-trifluoromethyl- pyridine and N-benzyl-3-methyl-5-trifluoromethylaniline were synthesized and assayed. 2-(4-Bromobenzylamino)-4-methyl-6-trifluoromethylpyrimidine exhibited the highest PET inhibitory activity against Spinacia oleracea thylakoids of all compounds tested. The 2-benzylaminopyrimidines and 2-methylpyrimidines having a 4-halobenzylamino group exhibited higher PET inhibition than atrazine and 2-trifluoromethylpyrimidines against Spinacia oleracea thylakoids. These PET inhibitory active compounds also exhibited a strong and similar inhibition both against atrazine-resistant Chenopodium album thylakoids as well as against thylakoids from wild-type Chenopodium. The herbicidal activity of 4-(4-bromobenzylamino)-2-methyl-6- trifluoromethylpyrimidine was equivalent to that of known herbicides like simetryne, simazine or atrazine.

Diagnostic accuracy of intraoperative imprint cytology in ovarian epithelial tumors

OBJECTIVE

To evaluate imprint cytology (IC) as the intraoperative pathological consultations for ovarian epithelial tumors (OET).

METHOD

We reviewed ICs obtained from 354 consecutive surgical specimens of OET. Cytological specimens were classified into five categories. Final pathological diagnoses were made according to the WHO classification. We performed logistic regression analysis, calculated the limits among benign, borderline, and malignant lesions, and analyzed the diagnostic accuracy. We also made receiver operating characteristic (ROC) curves regarding IC.

RESULTS

The accuracies to differentiate benign and malignant lesions were 87.1 and 83.6%, respectively. In contrast, that of borderline lesions was 30.0%. The areas under ROC curves to diagnose benign, and malignant lesions were 0.888 (P<0.05) and 0.951 (P<0.05), respectively, that meant IC was significantly useful for diagnosis of malignancy.

CONCLUSIONS

IC applied to OET was proved to be practically useful in establishing an intraoperative diagnosis by ROC curves.

[Optimal dosage of UFT in a weekday-on/weekend-off schedule as a postoperative adjuvant chemotherapy for colorectal cancer]

In evaluations of adjuvant chemotherapy with oral anticancer agents, compliance in taking the drug as prescribed (compliance), adverse reactions, and feasibility are important factors in setting the dose. A weekday-on/weekend-off schedule, in which 600 mg/day of UFT was taken for 5 consecutive days and not taken on the following 2 days, was carried out as a postoperative adjuvant chemotherapy for one year in 87 patients with colorectal cancer who had undergone potentially curative resection. The prescribed dose and the dose of ingestion confirmed by physician interview were both highly consistent with the dose of ingestion according to the patients' self reports, with consistency rates of more than 94% for both. Relative performance (RP) yielded a value of 0.72, and individual dose intensity (IDI) yielded 0.8 on average. Female gender, low body weight, and low body surface area were factors that negatively affected feasibility. None of the adverse reactions was serious. Based on the feasibility and adverse reactions, the dosage of UFT should be set according to the body surface area at 375-425 mg/m2/day. When this schedule is used as one arm of a controlled study, it is suggested that the dose should be decided with 400 mg/m2 as a guideline.

Feasibility of a novel weekday-on/weekend-off oral UFT schedule as postoperative adjuvant chemotherapy for colorectal cancer. UFT Compliance Study Group, Kanagawa, Japan

PURPOSE

When oral anticancer agents are used for adjuvant chemotherapy of colorectal cancer, compliance and feasibility become issues because of the long treatment time. Appropriate studies of these issues are lacking. We investigated compliance and feasibility during a weekday-on/weekend-off schedule of oral UFT (uracil-tegafur) over a period of 1 year administered as adjuvant chemotherapy to patients with colorectal cancer.

PATIENTS AND METHODS

A UFT dose of 600 mg/day was prescribed according to a weekday-on/weekend-off schedule to 87 patients after potentially curative resection. Compliance was investigated in three ways: physician interview, patient self-report, and chemical analysis of urine. The results were compared with the dose prescribed. Feasibility was evaluated on the basis of two indices: relative performance (RP), which was the ratio of the actual total dose taken to the total dose planned, and individual dose intensity (IDI), which was the ratio of the actual dose taken to the dose planned during a given period.

RESULTS

The compliance assessed by physician interview and by patient self-report conformed well with the prescribed dose, the rate of agreement among the three compliance measures being more than 94%. Chemical analysis of urine in 38 of the patients revealed that they were actually taking the drug. The RP was 0.72, and the IDI was 0.8.

CONCLUSION

From these results, the feasibility of the weekday-on/weekend-off schedule was judged to be good. It is suggested that the feasibility would be even better if the dose of UFT was set according to body surface area.

Obesity and postoperative oxygenation after coronary artery bypass grafting

OBJECTIVE

The relationship between obesity and postoperative oxygenation after coronary artery bypass grafting was studied.

METHODS

Subjects were 68 patients undergoing solitary coronary artery bypass grafting--49 men and 19 women with a mean age of 64 years--divided into 3 groups by body mass index: group L with a body mass index of < 20 kg/m2 (n = 10), group M with a 20 < or = body mass index < 25 (n = 46), and group H with a 25 < or = body mass index (n = 12). Perioperative oxygenation was evaluated using respiratory indices measured preoperatively and 3 and 15 hours postoperatively.

RESULTS

Postoperative respiratory indices significantly increased from 0.23 to 0.67 (p < 0.001) at 3 hours and to 0.97 (p < 0.01) at 15 hours postoperatively in group L, from 0.27 to 0.80 (p < 0.001) and to 0.94 in group M, and from 0.31 to 1.39 (p < 0.001) and to 1.45 in group H. The postoperative respiratory index in group H was significantly higher (p < 0.01) than that in groups M and L both at 3 and 15 hours postoperatively. Multivariate analysis showed that the coefficients of determination of body mass index to postoperative respiratory index, 23% at 3 hours and 16% at 15 hours postoperatively, were the highest among perioperative factors.

CONCLUSIONS

Obesity is a major factor impairing postoperative oxygenation. Careful management in a semirecumbent position and/or nasal intermittent positive pressure ventilation may thus be required in obese patients.

Accuracy and repeatability of blood volume measurement by pulse dye densitometry compared to the conventional method using 51Cr-labeled red blood cells

OBJECTIVE

To determine the accuracy and repeatability of pulse dye densitometry (PDD) in measuring blood volume (BV) by comparing it with the conventional method using 51Cr-labeled red blood cells (RI method) and by assessing sequential measurements.

DESIGN

Prospective clinical study.

SETTING

University hospital.

PATIENTS AND PARTICIPANTS

Eleven adult ICU patients who received cardiac surgery (1st ICU day).

INTERVENTIONS

None.

MEASUREMENTS AND RESULTS

After injecting indocyanine green (10 or 20 mg) into the right atrium, its arterial concentration was continuously monitored at the nose and finger by PDD, and BV was calculated by back extrapolating the logarithmic dye concentration on the dye elimination curve between 2.5 and 5.5 min after mean transit time to each mean transit time with the least squares method. These measurements were repeated in eight patients and performed only once in the other three, and the BV was measured concurrently by the RI method one time. The Bland-Altman method was used for evaluating differences between methods and within methods. The (percentage) biases and standard deviations between the PDD and RI methods and between the successive measurements by PDD at the finger and nose were 0.26 +/- 0.491 (8.8 +/- 15.3%) and 0.004 +/- 0.251 (0.06 +/- 5.9%) with the probe on a nostril, and 0.16 +/- 0.561 (2.5 +/- 14.4%) and 0.19 +/- 0.311 (4.7 +/- 7.3%) using the finger probe. The bias between methods was less than 10%, and the repeatability of PDD was better.

CONCLUSIONS

As PDD can measure BV with good repeatability and with a small bias compared to the RI method, serial changes in BV can be evaluated at the bedside of critically ill patients noninvasively and repeatedly.

Neonatal periventricular leukomalacia preceded by fetal periventricular echodensity

OBJECTIVE

The purpose of this prospective study is to verify whether fetal periventricular echodensity (PVE) precedes neonatal periventricular leukomalacia (PVL).

METHODS

Fetal brains were studied with transvaginal scan in 63 high-risk fetuses from 17 to 32 weeks of pregnancy, PVE echogenicity was quantified with ultrasonic histogram, and neonatal brains and clinical courses were studied after birth.

RESULTS

No fetal cystic PVL was found, instead, fetal PVE was detected in 42 fetuses. The quantified echogenicity value was higher in PVE than in normal brain. Four cases developed neonatal PVL among 28 preterm and 1 among 14 term births. Neonatal PVL developed in the 23 cases of persistent fetal PVE, whereas no neonatal PVL was found when fetal PVE was negative or disappeared. Cord compression signs were common in PVL cases.

CONCLUSION

Neonatal PVL was preceded by antepartum persistent fetal PVE in the present study.

Changes in gastric intramucosal pH and circulating blood volume following coronary artery bypass grafting

PURPOSE

To determine the changes in gastric intramucosal pH (pHi) following coronary artery bypass grafting (CABG) in comparison with systemic hemodynamic variables and circulating blood volume (BVc).

METHODS

Twenty patients who underwent CABG under mild hypothermic cardiopulmonary bypass (CPB) were included. Hemodynamic variables and the values of pHi were obtained at 3,6, 12 and 24 hr after admission to the intensive care unit (ICU). The pHi was measured by gastric tonometric catheter. The BVc was measured by carbon monoxide (CO)-labeled hemoglobin (CO-Hb) dilution method (CO method) at 6 and 24 hr after ICU admission.

RESULTS

Systemic vascular resistance index (SVRI) and pulmonary vascular resistance index (PVRI) decreased with time. Systemic oxygen delivery index (DO2I) and systemic oxygen consumption index (VO2I) showed a gradual increase during the study period. By contrast, pHi decreased to the lowest value (7.26+/-0.05) at six hours and returned to normal levels (7.34+/-0.04) at 24 hr after ICU admission. Changes in BVc between six and 24 hr ranged from -242 ml to 978 ml (mean, 334+/-338 ml). The pHi increased in patients whose BVc increased by > 300 ml. Mean fluid balance was negative in this period (-386+/-667 ml; range, -1786 - + 423 ml).

CONCLUSION

The pHi showed the lowest value at six hours and returned to normal at 24 hr after ICU admission. The pHi increased with the decrease in vascular resistance and with the increases in BVc in this period. The improvement of pHi, an indicator of splanchnic perfusion, appears to be related to systemic vasodilatation and an increase in BVc.

PEEP therapy for patients with pleurotomy during coronary artery bypass grafting

Severe pulmonary oxygenation impairment resulting from peripheral lung atelectasis occurred in some patients with pleurotomy during the harvest of the internal mammary artery graft followed by coronary artery bypass grafting (CABG). We studied the efficacy of intraoperative positive end-expiratory airway pressure (PEEP) therapy for the prevention of postoperative pulmonary oxygenation impairment. A total of 66 patients with solitary CABG procedure were included in this study. The pleural cavity was intraoperatively opened in 44 patients and not opened in 22. PEEP therapy was not used in any patient before May 1996 (referred to herein as the former period) and was used more recently in eight patients with pleurotopmy (referred to herein as the latter period). PEEP was initiated immediately after pleurotomy during the harvest of the internal mammary artery graft. Without PEEP therapy, values of PaO2, A-aDO2, and respiratory index (RI) were worse in patients with pleurotomy than in those without pleurotomy. Meanwhile, there were no major differences in these values between patients with or without pleurotomy after the induction of PEEP therapy. Respiratory insufficiency (A-aDO2 > 400 mmHg and RI > 1.5) was detected in six patients with pleurotomy in the former period. Three of these six patients required over 1 week of long-term mechanical respiratory support. No respiratory insufficiency occurred in patients of the latter period. In conclusion, PEEP therapy, which is initiated just after pleurotomy, may prevent oxygen impairment and pulmonary atelectasis after extracorporeal circulation (ECC) and is recommended for patients with pleurotomy, especially for patients with preoperative low respiratory function.

Computed tomography (CT) findings of gastric rupture after blunt trauma

A 49-year-old carpenter was hit by timber around his upper abdomen 1 hour after breakfast. Immediate computed tomography was taken, followed by emergency laparotomy showing gastric rupture accompanied with hemorrhage from the superior mesenteric vein. Hemostasis and distal partial gastrectomy followed by Billroth-I anastomosis reconstruction was performed. Here, we report the abdominal computed tomography findings from a patient with gastric rupture after blunt trauma. The present case, which is only the second such case reported in English literature, suggested that computed tomography is useful for assessing associated injuries in gastric rupture patients, for detecting intraperitoneal free air which can be missed by X-rays, and for locating the laceration of the rupture.

Postoperative oxygenation following coronary artery bypass grafting. A multivariate analysis of perioperative factors

BACKGROUND

Pulmonary oxygenation is generally temporarily impaired following cardiac surgery. We studied the factors influencing postoperative oxygenation using multivariate analysis.

METHODS

This study was retrospectively performed in University hospital. Fifty patients undergoing solitary coronary artery bypass grafting were included in this study. Patients were divided into two groups by mean age; older group (n=25) and younger group (n=25). Alveolar-arterial oxygen difference (A-aDO2) and respiratory index (RI) were measured at 3 hours after surgery and on postoperative day 1. Statistical analysis was performed using forward selection stepwise regression of 12 perioperative variables.

RESULTS

In all patients, A-aDO2 and RI significantly (p<0.01) increased after surgery and remained high on POD1. In stepwise regression analysis, preoperative A-aDO2 and RI were significant factors in the equations for postoperative A-aDO2 and RI in general, which was the most important factor in the older group. In the older group, preoperative A-aDO2 or RI and water balance were significant (p<0.05) factors which were responsible for half the oxygenation impairment just after surgery, and PCWP showed a significant (p<0.01) negative correlation with both A-aDO2 and RI on POD1. In the younger group, PCWP was a significant (p<0.01) factor for A-aDO2 and CVP and CI were significant for RI on POD1.

CONCLUSIONS

Postoperative oxygenation was mainly influenced by the preoperative respiratory condition, especially in old patients, indicating that preoperative management by a physiotherapist may be necessary. Pleurotomy also had a negative influence. Careful intraoperative and postoperative volume control is important in old patients.

[Staging laparoscopy for a patient with advanced gastric cancer whose serum CA 19-9 level decreased remarkably after 2 courses of F/P therapy]

The prognosis of patients with Stage IVb gastric cancer remains poor, and therapy for these patients is not easy. Recently, neoadjuvant chemotherapy is thought to be one of the better strategies for such patients. In this paper, we report a 48-year-old female patient with advanced gastric cancer whose serum CA 19-9 level decreased remarkably after 2 courses of F/P therapy. We also operated on this patient with staging laparoscopy, a new and more useful technique for the patients such as the present one. The advantages of staging laparoscopy are as follows: 1. The entire intraabdominal space can be observed from a small wound, and the clinical stage of the patient can be diagnosed more correctly. 2. It is easy to obtain cells from small amounts of ascites or tissues of small nodules in the abdominal wall and lymph node involvements. 3. Patients suffer less pain and movement of the body is not as limited after operation. 4. Administering drugs into the intra abdominal space is easy using this technique. Staging laparoscopy might therefore be one of the better surgical strategies for the patients with advanced patients when selecting a suitable therapy.

Accuracy of carboxyhemoglobin dilution method for the measurement of circulating blood volume

PURPOSE

The management of circulating blood volume (BVc) is crucial in intensive care unit (ICU) patients. The purpose of this study was to verify the accuracy and precision of the carbon monoxide-labeled hemoglobin (CO-Hb) dilution method (CO method) by comparing it with the 51Cr-labeled erythrocyte dilution method (51Cr method) for the measurement of BVc.

METHODS

A prospective study was performed in 18 patients who underwent coronary artery bypass grafting (CABG) under mild hypothermic cardiopulmonary bypass (CPB). The BVc was measured by both the CO method and the 51Cr method at 24 hr after ICU admission in order to verify the accuracy and precision of the CO method. Paired data were assessed in absolute terms, and percentage errors were calculated by the degree of agreement.

RESULTS

Small mean differences and standard deviations between the CO method and the 51Cr method (-70.2 +/-184.8 mL) and small percentage errors (-0.49+/-1.29%) indicated the accuracy and precision of the CO method, and a close correlation was observed (r = 0.97).

CONCLUSION

The CO method can measure BVc with a similar degree of accuracy as the 51Cr method. It is simple, repeatable and safe without the risk of exposure to radioactivity in the ICU.

[Successful treatment using detachable coils for traumatic carotid cavernous fistula as a complication of transsphenoidal surgery for a pituitary adenoma: a case report]

We report a case of a patient with traumatic carotid cavernous fistula (CCF) caused by transnasal-transsphenoidal surgery, who was successfully treated using detachable coils. A 47-year-old man was admitted to our hospital because of severe headache. He was confirmed to have a nonfunctioning pituitary adenoma with presellar-type sphenoid sinus. Cerebral angiography initially disclosed no vascular lesions. A transnasal-transsphenoidal adenomectomy was performed. When the anterior wall of the sphenoid sinus was dissected with a chisel, the chisel deeply stuck into the posterolateral part of the sinus. Profuse arterial bleeding was observed through the sphenoid sinus. The bleeding was stopped easily by compression and packing with bone wax. The operation was continued, the sellar floor was opened widely and the tumor was removed subtotally. The medial wall of the cavernous sinus was intact. Histological examination revealed a pituitary adenoma. Immediately after surgery, the patient noticed a bruit. He developed chemosis and abducent palsy on the right side. Cerebral angiography displayed a high-flow CCF, which was attributed to the carotid artery injury caused by the transnasal-transsphenoidal surgery. The CCF disappeared after two-staged embolization using detachable coils, 1st transvenous and 2nd transarterial. Ten months later, cerebral angiography showed persistent occlusion of the fistula, and the patient experienced no tumor recurrence. It is suggested that drilling is a safer procedure than using a chisel for dissection of a sphenoid sinus with incomplete pneumatization. Endovascular treatment using detachable coils proved useful to manage the CCF, an unusual complication of transsphenoidal surgery.

Low resistance against novel 2-benzylamino-1,3,5-triazine herbicides in atrazine-resistant Chenopodium album plants

The effects of nine novel 2-benzylamino-1,3,5-triazines on photosynthetic reactions were measured in thylakoids isolated from wild-type and atrazine-resistant plants of Chenopodium album. The resistant plants have a mutation of serine for glycine at position 264 of the D1 protein. The measurement of oxygen evolution and chlorophyll a fluorescence induction indicated a 2-4-fold stronger inhibition by the 6-trifluoromethyl analogues of Photosystem II-dependent electron flow than atrazine. Analogues having a 6-methyl-, 6-monofluoromethyl or 6-difluoromethyl substitution were weak inhibitors, indicating that the 6-trifluoro group is very important for strong inhibition. All the nine novel 2-benzylamino-1,3,5-triazines were almost as active in wild-type as in atrazine-resistant thylakoids, indicating that the benzylamino substitution may be important for the lack of resistance in the atrazine-resistant plants.

Comparison of the hemodynamic effects of amrinone in patients who required low-to-moderate-dose and high-dose catecholamines after cardiac valve replacement

OBJECTIVES

To determine hemodynamic response to amrinone in patients after cardiac surgery, in relation to the postoperative cardiac function, which was indicated by the required doses of catecholamines.

DESIGN

Prospective clinical study.

SETTING

Surgical intensive care unit in a university hospital.

PATIENTS

Fourteen patients who required a low-to-moderate dose of dopamine and dobutamine (group L) and 14 patients who required a high dose of dopamine and dobutamine (group H) after cardiac valve replacement.

INTERVENTIONS

A loading dose of amrinone (0.75 mg/kg) was administered during a 15-min period and the continuous infusion was followed incrementally by doses of 5, 10, and 20 microg/kg/min every 60 mins on the first postoperative day.

MEASUREMENTS AND MAIN RESULTS

Hemodynamic variables were determined by the radial and pulmonary artery catheters at a dose of 0, 5, 10, and 20 microg/kg/min. Two-way repeated-measures analysis of variance showed significant interaction in the two groups in cardiac index and mean systemic arterial pressure. Cardiac index increased in a dose-dependent manner in group L but was unchanged in group H. Systemic vascular resistance index decreased in a dose-dependent manner in both groups. The mean systemic arterial pressure decreased in group L at a dose of 5 microg/kg/min and returned to the baseline level at doses of 10 and 20 microg/kg/min. On the other hand, the mean systemic arterial pressure significantly decreased in group H at a dose of 20 microg/kg/min.

CONCLUSIONS

The inotropic effects of amrinone after cardiac valve replacement may be associated with the postoperative myocardial reserve, which was indicated by the required doses of catecholamines, although a similar vasodilative effect was observed in both groups.