Mechanisms involved in enteropathy induced by administration of nonsteroidal antiinflammatory drugs (NSAIDS)

Mice received oral indomethacin (1 mg/mouse) daily for five days. It was found that severe gastroenteropathy (ie, paralytic stomach and necrotic intestine) was induced on the sixth day. Ulcer formation was also seen at many sites in the digestive tract, especially in the colon. In parallel with the increase in the number of leukocytes in the digestive tract, the proportion of granulocytes increased at various sites, for example, in the intraepithelium and lamina propria of the colon and the lamina propria of the appendix. The number of extrathymic T cells at these sites in the digestive tract, especially gammadelta T cells in the colon, increased. A functional assay revealed that granulocytes isolated from mice injected with indomethacin were activated in terms of their superoxide production upon stimulation. In conjunction with the data on the simultaneous activation of granulocytes in the liver and blood, the present results suggest that nonsteroidal antiinflammatory drugs (NSAIDs) have the potential to induce severe granulocytosis in specific sites of the body, possibly via their stimulatory effect on the sympathetic nervous system (ie, granulocytes bear adrenergic receptors on their surface).

Liver-infiltrating CD56 positive T lymphocytes in hepatitis C virus infection

AIM

Hepatitis C virus (HCV) is a major cause of post-transfusional and sporadic hepatitis, and leads to chronic liver disease. It has been suggested that virus-specific cytotoxic T lymphocytes are responsible for liver injuries that occur in HCV-infected patients. However, the detailed characteristics of these lymphocytes have not yet been defined. We have previously reported that CD56+ T lymphocytes, as intermediates between natural killer cell and T lymphocytes, predominantly infiltrated the liver and were increased in patients with chronic hepatitis related to HCV (CH-C).

MATERIAL AND METHODS

We obtained peripheral blood and liver tissues from 32 patients diagnosed as having CH-C, and 10 other liver disease patients (5 chronic hepatitis related to HBV, 5 alcoholics), and analyzed peripheral blood and liver-infiltrating lymphocytes using flow cytometric and immunohistochemical techniques.

RESULTS

The CD56+ T lymphocyte ratio in the liver of patients with a high histology activity index (HAI) score for chronic hepatitis was higher than that of patients with a low HAI score and patients with other liver diseases. In addition, T lymphocytes from patients with chronic hepatitis with a high HAI score carried mostly gamma delta-TCR. There was a correlation between the ratio of CH-C and serum alanine aminotransferase, category I (periportal inflammation and necrosis), and IV (fibrosis) of the HAI scoring system. The ratio was highest in zone 1 of the hepatic lobules.

CONCLUSION

The correlation between CD56+ T lymphocyte ratios and hepatocellular damage was examined. These findings suggest strongly that liver-infiltrating CD56+ T lymphocytes play an important pathologic role in hepatocellular injury in CH-C.

Detection of intracellular interleukin-2 production in peripheral T lymphocytes by flow cytometry in patients with pancreatobiliary malignancies

BACKGROUND AND AIMS

To date, it has been reported that cellular immunity is decreased in patients with cancer and investigations into cytokine production has been insufficient. Therefore, we examined intracellular cytokine production by using flow cytometry in patients with cancer and discussed the reasons for the impairment of their immune system.

METHODS

Eleven patients with hepatobiliary malignancies (68.5+/-11.8 years of age), eight age-matched controls (70.0+/-12.0 years of age) and 10 young volunteers (31.9+/-3.1 years of age) were used in the present study. Stimulated peripheral blood mononuclear cells from these patients were stained with fluorescence-labeled anticytokine monoclonal antibodies and analyzed with a Fluorescence activated cell sorter (FAC)Scan.

RESULTS

The percentage of positively stained T cells was calculated and compared with controls. Repeated measured ANOVA was used for statistical analysis. Interleukin (IL)-2 production was significantly decreased in patients with cancer compared to controls (P=0.0122), and it may suggest decreased cellular immune activity of the patients. Simultaneously, spontaneous intracellular IL-4 production was observed in patients and age-matched controls, but levels were significantly increased when compared with the young volunteers (P=0.0052, P=0.031, respectively).

CONCLUSIONS

It was of interest that spontaneous intracellular IL-4 production was detected in elderly subjects.

[The effect of acetate ringer solution, 6% hydroxyethyl starch saline and 20% mannitol solution on the serum concentration of propofol continuously infused]

Changes in serum concentrations of propofol after administration of three different fluids were investigated in 42 scheduled surgical patients. Anesthesia was induced with propofol 2 mg.kg-1 and maintained with constant rate infusion of propofol 6 mg.kg-1.hr-1. After achieving a stable depth of anesthesia, 5 ml.kg-1 of acetate Ringer's solution, 6% hydroxyethyl starch saline solution or 20% mannitol solution was infused in 15 minutes. Blood samples each 2 ml were taken before and 0, 5, 15, 30 and 60 minutes after fluid treatment. We measured hemoglobin and hematocrit of the samples for calculating the dilution rate of the plasma with infusion treatment, and determined the serum concentration of propofol by HPLC-spectrofluorometry. After administration of each fluid, the serum concentrations of propofol decreased significantly to 17 +/- 15, 25 +/- 10 and 35 +/- 8%, respectively (mean +/- SEM). The dilution rate of the plasma from the fractional change in blood hemoglobin increased to 0.08 +/- 0.02, 0.24 +/- 0.03, and 0.36 +/- 0.03, respectively. Administration of mannitol might markedly increase distribution volume of propofol, and this can be attributed to osmotic action of mannitol and resultant expansion of extracellular fluid volume. The results of the present investigation suggest that this pharmacokinetic change decreased the concentration of propofol more significantly in mannitol treatment patients than in Ringer's solution or 6% hydroxyethyl starch saline treatment patients.

Vitamin B6 supplementation can improve peripheral polyneuropathy in patients with chronic renal failure on high-flux haemodialysis and human recombinant erythropoietin

BACKGROUND

High-flux haemodialysis (HD) has recently been vigorously promoted as a novel standard, and it can indeed efficiently reduce the occurrence of most uraemic symptoms due to middle molecular toxins and/or underdialysis. However, some symptoms remain problematical, particularly peripheral polyneuropathy (PPN). One of the possible reasons for this is that the patients may have low concentrations of some nutrients, e.g. vitamin B(6), necessary for normal peripheral neuron function.

METHODS

Predialysis serum pyridoxal-5'-phosphate (P5P) level was determined in 36 chronic HD patients who were undergoing high-flux HD and receiving human recombinant erythropoietin. Among them, 26 patients suffered from PPN. Prior to supplementation, these 26 patients were examined and their neurological symptoms were ranked according to our PPN symptom score. Vitamin B(6) (60 mg/day) was randomly prescribed to 14 of them, and vitamin B(12) (500 microg/day) was prescribed to the others. After 4 weeks, all the patients were re-examined.

RESULTS

We found that predialysis serum P5P levels of HD patients with PPN were not significantly lower than those of matched HD patients without PPN. Nonetheless, it was demonstrated that supplementation with vitamin B(6) for 4 weeks significantly increased the predialysis level of P5P and dramatically attenuated PPN symptoms compared with initial symptoms. No improvement was observed in response to vitamin B(12) supplementation.

CONCLUSION

This result suggests that although vitamin B(6) deficiency could not be demonstrated in patients with chronic renal failure on high-flux HD, vitamin B(6) supplementation was effective in improving PPN symptoms of various aetiologies, possibly because of vitamin B(6) resistance to PPN in these patients.

Tubular osteopontin expression in human glomerulonephritis and renal vasculitis

Tubulointerstitial change is a common histopathologic feature of acute and chronic glomerular diseases and is more closely correlated than glomerular damage with renal function and subsequent outcome. Monocyte infiltration is presumed to be initiated by chemoattractants and has a pivotal role in tubulointerstitial changes. Osteopontin (OPN) is a candidate as such a chemoattractant and has been shown to recruit monocytes into the interstitium of animal models of renal diseases. In this study, we investigated OPN expression by immunostaining and its correlation with clinical and histopathologic parameters in patients with immunoglobulin A (IgA) nephropathy, diffuse proliferative lupus nephritis (DPLN), and myeloperoxidase-antineutrophil cytoplasmic autoantibody-associated microscopic polyangiitis (MMP). Twenty patients with IgA nephropathy, 12 patients with DPLN, and 14 patients with MMP were studied. OPN expression, which was constitutively observed on the apical membrane of distal tubules, was upregulated in the cytoplasm of proximal and distal tubular epithelium parallel to the degree of interstitial mononuclear cell infiltration in patients with IgA nephropathy, as well as those with DPLN. CD68(+) monocyte infiltration significantly correlated with the degree of OPN expression in the tubular epithelium. Conversely, there was no apparent induction of OPN in the proximal and distal tubular epithelium of patients with MMP despite remarkable monocyte infiltration. In conclusion, these data suggest that inducible expression of OPN in the tubular epithelium seems to be associated with interstitial monocyte infiltration and subsequent tubulointerstitial changes in some forms of human renal diseases.

[Successful fiberoptic intubation for a patient with lingual tonsillar hyperplasia]

Hypertrophied lingual tonsils are rare, but may cause difficulty or inability in tracheal intubation during induction of general anesthesia. A 39-yr-old woman was scheduled for resection of symptomatic hypertrophied lingual tonsils. In this patient, we examined two methods of oro-tracheal intubation either with rigid laryngoscopy or flexible fiberoscopy using trans-nasal fiberopic monitoring. Direct laryngoscopy failed to expose the trachea because of large hypertrophied tissue, and fiberoscopic intubation was also difficult since a large mass hindered acquiring a suitable view. However, transnasal fiberoscopic monitoring could guide the orotracheal fiber into the trachea for intubation. When an anesthesiologist can predict the abnormality of lingual tonsils, this combination might be recommended for difficult airway and intubation.

Liposome-encapsulated OK-432 specifically and sustainedly induces hepatic natural killer cells and intermediate T cell receptor cells

BACKGROUND

OK-432 is a biological response modifier used in Japan to augment host immunity and is known to increase the host antitumour response. By using liposomes, which are vesicles made from phospholipids that have a structure resembling the cell membrane, we encapsulated OK-432.

METHODS AND RESULTS

Encapsulated OK-432 was injected into the tail veins of mice, and its effect was compared with that of unencapsulated OK-432 given intravenously. In mice that received either form of OK-432, both the number of natural killer (NK) and intermediate T cell receptor (intTCR) cells (intrahepatic T cells generated by extrathymic differentiation) increased markedly in the liver, with the peak level occurring 3 days after administration. Both forms of OK-432 also increased cytotoxic activity against Yac-1 cells. The increase in numbers of cells and in cytotoxic activity in the liver persisted for longer in mice that received encapsulated OK-432 than in animals that received unencapsulated OK-432.

CONCLUSIONS

Because it has been shown that both NK and intTCR cells play an important role in tumour immunity, an increase in the number of such cells can be considered likely to have an increased antitumour effect. Encapsulated OK-432 elicited liver-specific augmentation of cytotoxic activity and the effect was more persistent than that produced by OK-432 given in the conventional form; therefore, it may be useful for the treatment of tumours, particularly those arising in the liver.

Subtraction CT with low-flow-rate arterial contrast injection to estimate drug distribution during balloon-occluded arterial chemotherapy infusion for bladder cancer

PURPOSE

To simulate drug distribution during balloon-occluded arterial chemotherapy infusion (BOAI) for urinary bladder cancer using subtraction computed tomography (CT) with low-flow-rate arterial contrast injection (S-CTLA).

METHODS

Ten patients with bladder cancer underwent S-CTLA, and the distribution of contrast agent during BOAI into both internal iliac arteries simultaneously was evaluated in nine pairs of internal iliac arteries and one single artery. For S-CTLA, spiral CT data were acquired before and after 0.2 ml/sec intraarterial injection of contrast material. The enhancement of the urinary bladder wall, the gluteal muscles, and the pelvic bones was categorized using a 4-grade scale. The grades were compared in each of the three pelvic components and differences were tested for significance using the Wilcoxon test for paired groups.

RESULTS

S-CTLA revealed the distribution of the contrast agent clearly. Gluteal muscles grades were significantly higher than those of the other two assessed components.

CONCLUSION

BOAI does not improve the concentration of contrast agent to the bladder wall over neighboring structures, suggesting that the balloon occlusion technique does not achieve its desired goal for chemotherapy targeting.

Incidence of gingival hyperplasia caused by calcium antagonists in continuous ambulatory peritoneal dialysis patients

Calcium antagonists are widely used for the treatment of cardiovascular diseases in patients receiving dialysis therapy. The incidence of gingival hyperplasia has been reported as 10%-20% in patients treated with calcium antagonists in the general population. However, precise reports examining the incidence or pathogenesis of gingival hyperplasia in continuous ambulatory peritoneal dialysis (CAPD) patients are lacking. We recruited 54 CAPD patients. Three patients treated with long-acting nifedipine and one patient treated with felodipine were reported by a periodontist to have gingival hyperplasia. No patients were taking amlodipine and other calcium antagonists. After discontinuation of calcium antagonists, gingival hyperplasia disappeared within 1 month. Based on these results, we suggest that it is important to examine whether the gingiva is overgrown in CAPD patients taking calcium antagonists.

Evidence that gender difference affects peritoneal dialysis capacity in continuous ambulatory peritoneal dialysis patients

The progression of renal disease is reported to be more rapid in male patients than in premenopausal females. However, few studies compare the difference in dialysis therapy between males and females. We compared the efficacy of peritoneal dialysis capacity, using measurements of retention volume and pelvic cavity by helical section of computed tomography (CT) in 6 male and 6 female patients. The patients did not differ significantly in age (males: 54 +/- 3 years; female: 56 +/- 4 years). Males were heavier than females (p < 0.05). Retention volume in the visceral cavity was significantly larger in males (1787 +/- 43 mL) than in females (1580 +/- 59 mL) (p < 0.05). Peritoneal dialysis capacity was evaluated by peritoneal equilibration test (PET). Although no significant differences were observed in the PET data, when the PET results at 4 hours were divided by body weight in kilograms, a significant difference between males and females was seen (p < 0.05). There was a mild, but not significant, correlation between the volume of the pelvis as measured by helical CT and the PET data per kilogram body weight (p = 0.07). These results suggest that gender differences in peritoneal dialysis capacity relate partially to the difference in pelvic cavity volume.

[A patient for craniotomy with ECG abnormality occurring on admission to the operating room]

We report a 72 year old male patient for craniotomy with ECG abnormality occurring on admission to the operating room. His preoperative ECG showed normal sinus rhythm without ST-T change and T wave abnormality. On admission to the operating room, negative T wave was noted on the ECG monitor. Therefore, we applied isosorbide dinitrate tape after the induction of anesthesia. When the dura mater was opened, subarachnoid hemorrhage was noticed. Intraoperative pathological examination revealed a glioblastoma multiforme. The tumor bled from inside and outside. The perioperative T wave abnormality was probably due to subarachnoid hemorrhage or bleeding from the tumor itself. The T wave abnormality disappeared on the 10th postoperative day.

[Investigations on the position and safety of Swan-Ganz catheters]

Swan-Ganz catheters (S-G catheter) may cause many complications. We measured floating distance (FD) of catheter tip with balloon inflation or deflation, and distal movement (DM) before and after the operation. FD and DM were significantly altered with 7 Fr. S-G catheters. These results suggest that careful observation is required in order to prevent unpredictable pulmonary artery perforation and infarction during the use of 7 Fr. S-G catheters.

Control of blood pressure and prevention of end-organ damage in patients with accelerated hypertension by combination with arotinolol and extended release nifedipine

In patients with accelerated (malignant) hypertension, end-organ damage is the determinant factor for prognosis. Although recent advances in antihypertensive therapy have improved the outcome of patients with accelerated hypertension, the effectiveness of antihypertensive therapy still remains less convinced. In this study, we followed 13 patients clinically diagnosed with accelerated hypertension (defined as diastolic blood pressure > 130 mmHg, retinopathy with K-W IV and accelerated renal impairment) for 3 yr. One patient died due to acute myocardial infarction arising from poor compliance with antihypertensive therapy. One patient was maintained on hemodialysis for 3 yr. One patient was introduced for continuous ambulatory peritoneal dialysis (CAPD) for a year and then lived without dialysis therapy. The remaining 10 patients were followed for 3 yr. All patients were initially treated with intravenous administration of calcium antagonist for reduction of blood pressure, followed by hemodialysis therapy if needed. After stabilization of blood pressure, combination therapy with extended release nifedipine (40 to 80 mg daily) and arotinolol (20 mg daily) was started. The targets for blood pressure control were a systolic pressure of 135 mmHg and a diastolic pressure of 80 mmHg. If blood pressure control was unsatisfactory, guanabenz (2 to 4 mg before bedtime), a central acting drug, was added. At presentation, the mean diastolic blood pressure (mDBP) among the 10 remaining patients was 134 +/- 2 mmHg, the mean serum creatinine (mScr) was 4.5 +/- 0.7 mg/dl and the left ventricular mass index (LVMi) as measured by echocardiography was 150 +/- 9 g/m2. At 1 yr, the mDBP was reduced to 90 +/- 3 mmHg, the mScr to 2.9 +/- 0.9 mg/dl and the LVMi to 140 +/- 9 g/m2. At 3 yr, the mDBP was stabilized at 79 +/- 3 mmHg, the mScr maintained at 2.2 +/- 0.4 mg/dl, and the LVMi reduced to 128 +/- 9 g/m2. These results indicate that appropriate blood pressure control is important for improvement of renal impairment and cardiac damage in patients with accelerated hypertension. Moreover, combination therapy with arotinolol and extended release nifedipine may be beneficial for this purpose.

Prognostic significance of the PC10 index for patients with stage II and III oesophageal cancer treated with radiotherapy

The monoclonal antibody PC10 is used for immunohistochemical staining of the proliferating cell nuclear antigen (PCNA). The percentage of PC10-positive cancer cells is defined as the PC10 index. We evaluated the relationship between the PC10 index in pretreatment endoscopic biopsies and the prognoses of 47 patients with Stage II-III oesophageal squamous cell carcinoma treated with radiotherapy. The patients with a PC10 index > 40% had significantly poorer prognoses than the other patients (p = 0.0007). Proportional hazards model analysis indicated that only the PC10 index was a prognostic factor (p = 0.0009). The patient group of complete responders showed significantly lower PC10 indices compared to patients with a partial response or no change (p = 0.049). The PC10 index can be a good predictive indicator of the prognosis in patients with Stage II-III oesophageal cancer treated with radiotherapy.

[Patterns of initial treatment failure of esophageal cancer following radiotherapy]

Sixty patients with stage I-III esophageal squamous cell cancer treated by definitive radiotherapy (RT) were analyzed for patterns of treatment failure. Patients were treated by external RT alone (n = 45) or in combination with intraluminal RT (N = 15) when suitable, with prescribed total doses ranging from 59.4 to 104.4 Gy. Concurrent chemotherapy consisting of cisplatin and/or 5-fluorouracil was administered to 19 patients. The two-year actuarial survival rate and two-year disease-free survival rate were 29.5% and 18.3%, respectively. Two-year failure rates were 66.5%, 36.9%, and 3.8%, for the esophagus, lymph nodes, and other sites, respectively. Two-year esophageal failure rates for patients with T1-2 (n = 8), T3 (n = 30), and T4 disease (n = 22) were 14.3%, 64.7%, and 87.9%, respectively (p < 0.05). A multivariate analysis of esophageal failure with descriptive variables of T classification, tumor length, and performance of intraluminal RT revealed that only T classification was an independent factor (p = 0.021). Two-year lymph node failure rates were 24.8% and 33.6% for patients with N0 (n = 36) and N1 disease (n = 24), respectively (p = 0.0035). Lymph node failure in N0 patients was found exclusively outside the treatment field. These results suggest that inclusion of potential lymph node metastases in the radiation field could lessen the lymph node failure rate in T1-3N0M0 patients.

The majority of lymphocytes in the bone marrow, thymus and extrathymic T cells in the liver are generated in situ from their own preexisting precursors

Parabiotic pairs of B6.Ly5.1 and B6.Ly5.2 mice were used to investigate how lymphocytes in various organs and various lymphocyte subsets mixed with partner cells. The origin of partner cells was determined by using anti-Ly5.1 mAb in conjunction with immunofluorescence tests. Parabiosis was also produced after the irradiation of B6.Ly5.2 mice at various doses to prepare an immunosuppressive partner. Irrespective of irradiation, lymphocytes and other hematopoietic cells in the bone marrow and lymphocytes in the thymus showed a low mixture of partner cells in comparison with those of all other organs tested. On the other hand, lymphocytes in the blood, spleen, and lymph nodes became a half-and-half mixture of their own cells and partner cells by 14 days after parabiosis. Among lymphocyte subsets, intermediate CD3 cells (i.e., CD3int cells) and NKT cells (i.e., NK1.1+ subset of CD3int cells) in the liver also showed a low mixture of partner cells. The present results raise the possibility that lymphocytes in the bone marrow and thymus, and extrathymic T cells in the liver might be in situ generated from their own preexisting precursor cells. Another observation was that, after irradiation, partner cells showed accelerated mixture even if they showed a low mixture under non-irradiated conditions. However, only lymphocyte subsets with the same phenotype as those of preexisting cells entered the corresponding sites.

Nifedipine and arotinolol in combination for accelerated-malignant hypertension: results of one year follow-up

The effects of a combined therapy with a calcium channel antagonist and alphabeta-blocker in patients with accelerated-malignant hypertension on blood pressure and renal function were examined. Thirteen patients presented with the clinical features of malignant hypertension (diastolic blood pressure >130 mmHg, retinal damage and progressive renal failure) at our hospital, over the 3 yr period from 1995 to 1997. These patients were treated with both a calcium antagonist, 60-80 mg/d dose of long acting nifedipine, and an alphabeta-blocker, 20 mg/d dose of arotinolol, for over 12 mo. At admission, the average blood pressure of the patients was 233+/-8/144+/-3 mmHg. The level of serum creatinine in these patients was 6.2+/-1.0 mg/dl. Intermittent hemodialysis therapy was introduced in 7 patients. Three days after treatment, blood pressure decreased to 162+/-4/102+/-4 mmHg. A month later, blood pressure decreased to 148+/-3/89+/-2 mmHg and serum creatinine levels were 3.6+/-0.4 mg/dl. Renal function in these patients improved, and they completely recovered from renal dysfunction, allowing withdrawal of haemodialysis therapy. One year later, the blood pressure in all of these patients was well controlled and no further renal deterioration was observed, except in one patient. Despite the reduction in blood pressure, one patient was on hemodialysis three times a week after 8 mo of treatment. From these finding, it is concluded that combination therapy with a calcium antagonist and alphabeta-blocker is effective in both the reduction of highly elevated blood pressure and protection of the kidneys, resulting in amelioration of accelerated-malignant hypertension.

Thoracoscopic surgery and pleurodesis for pleuroperitoneal communication in patients on continuous ambulatory peritoneal dialysis

Two patients on continuous ambulatory peritoneal dialysis (CAPD) developed right massive hydrothorax and were diagnosed as having pleuroperitoneal communication. Thoracoscopic surgery and pleurodesis were performed. It showed that one was caused by multiple flaws in the diaphragm and that the other was attributable to multiple blebs in the diaphragmatic dome. After the procedure, both of them had no recurrence of hydrothorax and underwent CAPD safely. We recommend thoracoscopic surgery and pleurodesis as the first choice of therapeutic methods for pleuroperitoneal communication.

Mechanisms involved in graft-versus-host disease induced by the disparity of minor histocompatibility M1s antigens

In this study we investigated which type of T cells: high T-cell receptor (TCRhigh, cells of thymic origin) or intermediate TCR (TCRint, cells of extrathymic origin), expanded in the liver and other organs, resulting in the induction of graft-versus-host disease (GVHD) with minor lymphocyte stimulating (M1s) disparity. When 6.5 Gy-irradiated BALB/c (H-2d M1s-1b2a) mice were injected with interleukin-2 receptor beta-chain(-) (IL-2Rbeta(-)) CD3high cells purified from the spleen of B10.D2 (H-2d M1s-1b2b) mice, IL-2Rbeta(+)CD3high cells expanded in the liver and other organs of recipient mice. The majority of these cells were found to be IL-2Ralpha(-)Mel-14(-)CD4(+)Vbeta3(+) in GVHD mice. The CDR3 region in their TCR-alphabeta (i.e. N-Dbeta-N) was polyclonal, although there were skewed usages of Vbeta3 and Jbeta2.4. The majority of cells were confirmed to be of donor origin by the individual discrimination method, namely, they originated from isolated IL-2Rbeta(-)CD3high cells. Interestingly, these T cells lacked cytotoxicity against both a natural killer (NK)-sensitive target and thymocytes with M1s disparity and nondisparity. Another important finding was that activated granulocytes expanded at generalized sites in GVHD mice. The present results raise the possibility that M1s disparity is mainly recognized by TCRhigh cells with unique properties but that direct effector cells that induce GVHD might not be such T cells but rather accompanied granulocytes.

Does intensive perioperative dialysis improve the results of coronary artery bypass grafting in haemodialysed patients?

BACKGROUND

Between January 1996 and April 1998, 17 chronic haemodialysed patients underwent coronary artery bypass grafting (CABG). Two of them simultaneously had valve replacement.

METHODS

Except for two cases in which CABG was performed in an emergency, 15 patients (CRF group) received 3 consecutive days of haemodialysis in the preoperative period, intraoperative haemodialysis connected to cardiac pulmonary bypass (CPB) and continuous hemodiafiltration in the early postoperative period. The perioperative clinical parameters of the CRF group were compared with those of 17 age-matched patients with normal renal function undergoing CABG as the control (NRF group).

RESULTS

When the perioperative variables were compared, no significant differences were seen in total operation time and CPB time, but we noted significant increases in the mean volume of transfused blood in the 6 perioperative days, postoperative intubation time, postoperative fasting time, and time spent in the intensive care unit. Levels of central venous pressure, systolic blood pressure, respiratory index (PaO2/FiO2) and daily fluid balance of the CRF group were the same as the control group in the early postoperative period. In addition, the levels of serum creatinine, urea nitrogen, potassium and hematocrit of CRF group remained almost constant in the early postoperative period. After all, the hospital morbidity of the CRF group was not more serious than that of the NRF group, and hospital mortality of the CRF and NRF groups was 0%.

CONCLUSIONS

Our intensive perioperative dialysis programme could successfully manage the perioperative clinical course of haemodialysed patients undergoing CABG.

Extrathymic derivation of gut lymphocytes in parabiotic mice

In adult mice, c-kit+ stem cells have recently been found in their liver, intestine and appendix, where extrathymic T cells are generated. A major population of such thymus-independent subsets among intraepithelial lymphocytes is T-cell receptor (TCR)gamma delta+ CD4- CD8alpha alpha+(beta-) cells, but the origins of other lymphocyte subsets are still controversial. In this study, we examined what type of lymphocyte subsets were produced in situ by such stem cells in the small intestine, large intestine and appendix. To investigate this subject, we used parabiotic B6.Ly5.1 and B5.Ly5. 2 mice which shared the same circulation by day 3. The origin of lymphocytes was identified by anti-Ly5.1 and anti-Ly5.2 monoclonal antibodies in conjunction with immunofluorescence tests. Lymphocytes in Peyer's patches and lamina propria lymphocytes (especially B cells and CD4+ T cells) in the small intestine became a half-and-half mixture of Ly5.1+ and Ly5.2+ cells in each individual of parabiotic pairs of mice by day 14. However, the mixture was low in CD8alpha alpha+, CD8alpha beta+ and gamma delta T cells in the small and large intestines and in CD3+ CD8+ B220+ cells in the appendix. These cells might be of the in situ origin. When one individual of a pair was irradiated before parabiosis, the mixture of partner cells was accelerated. However, a low-mixture group always continued to show a lower mixture pattern than did a high-mixture group. The present results suggest that extrathymic T cells in the digestive tract may arise from their own pre-existing precursor cells and remain longer at the corresponding sites.