Involvement of Ras and Ral in chemotactic migration of skeletal myoblasts

In skeletal myoblasts, Ras has been considered to be a strong inhibitor of myogenesis. Here, we demonstrate that Ras is involved also in the chemotactic response of skeletal myoblasts. Expression of a dominant-negative mutant of Ras inhibited chemotaxis of C2C12 myoblasts in response to basic fibroblast growth factor (bFGF), hepatocyte growth factor (HGF), and insulin-like growth factor 1 (IGF-1), key regulators of limb muscle development and skeletal muscle regeneration. A dominant-negative Ral also decreased chemotactic migration by these growth factors, while inhibitors for phosphatidylinositol 3-kinase and mitogen-activated protein kinase kinase (MEK) showed no effect. Activation of the Ras-Ral pathway by expression of an activated mutant of either Ras, the guanine-nucleotide dissociation stimulator for Ral, or Ral resulted in increased motility of myoblasts. The ability of Ral to stimulate motility was reduced by introduction of a mutation which prevents binding to Ral-binding protein 1 or phospholipase D. These results suggest that the Ras-Ral pathway is essential for the migration of myoblasts. Furthermore, we found that Ras and Ral are activated in C2C12 cells by bFGF, HGF and IGF-1 and that the Ral activation is regulated by the Ras- and the intracellular Ca(2+)-mediated pathways. Taken together, our data indicate that Ras and Ral regulate the chemotactic migration of skeletal muscle progenitors.

Synthesis of axially chiral benzamides utilizing tricarbonyl(arene)chromium complexes

Axially chiral N,N-diethyl 2,6-disubstituted benzamides were stereo-selectively prepared utilizing planar chiral (arene)chromium complexes as an enantiomerically active form by following two methods. Ortho-lithiation of the enantiomerically pure planar chiral tricarbonyl(N,N-diethyl 2-methylbenzamide)chromium complex followed by electrophilic quenching gave axially chiral 2-methyl-6-substituted N,N-diethyl benzamide chromium complexes. Photo-oxidative demetalation produced the chromium-free axially chiral benzamides as optically active compounds. An alternative method for the preparation of axial chiral benzamides is an enantioselective lithiation at the benzylic methyl of meso tricarbonyl(N,N-diethyl 2,6-dimethylbenzamide)chromium with appropriate chiral lithium amide base followed by quenching with alkyl halides.

Effect of plasma exchange on serum tissue inhibitor of metalloproteinase 1 and cytokine concentrations in patients with fulminant hepatitis

AIMS

The present study assessed whether the serum concentrations of tissue inhibitor of metalloproteinase 1 (TIMP-1) and cytokines are altered in patients with fulminant hepatitis and whether plasma exchange affects these concentrations.

METHODS

Fifteen patients with fulminant hepatitis, 14 patients with severe acute hepatitis, and 20 healthy controls were included in this study. The serum levels of tumor necrosis factor alpha (TNF-alpha), interleukin 1beta (IL-1beta), interleukin 6 (IL-6), transforming growth factor beta (TGF-beta), and TIMP-1 were determined in all patients upon hospital admission and before and after a single course of plasma exchange in the patients with fulminant hepatitis.

RESULTS

Ten out of the 15 patients with fulminant hepatitis and all patients with severe acute hepatitis survived. Serum TNF-alpha, IL-6, TGF-beta, and TIMP-1 levels in patients with fulminant hepatitis were significantly higher than the levels in patients with severe acute hepatitis (p < 0.01). IL-1beta was not detectable in either group. Plasma exchange reduced the increased serum concentrations of TNF-alpha, IL-6, TGF-beta, and TIMP-1 in patients with fulminant hepatitis (p < 0.01).

CONCLUSIONS

These data suggest that increased serum levels of TIMP-1 and cytokines may reflect severe hepatic inflammation and that plasma exchange is an effective therapy to reduce these levels.

Pathologic, cytologic and immunohistochemical findings of an intra-abdominal desmoplastic small round cell tumor in a 15-year-old male

The intra-abdominal desmoplastic small round cell tumor is a rare neoplasm. It usually occurs in young males and diffusely involves the peritoneum and pursues an aggressive clinical course. The present patient was a 15-year-old male who experienced abdominal pain and abdominal swelling. The patient was diagnosed with an intestinal myogenic sarcoma, and surgery for tumor resection was performed in June 1999. The tumor was a 20 x 15 x 15 cm well-defined mass in the peritoneum involving the transverse colon and stomach with peritoneal disseminations and splenic metastasis. Microscopic findings were well-defined nests composed of small round cells and separated by abundant desmoplastic stroma. Cytologically, the tumor cells consisted of small, round to oval cells with a scant amount of light blue cytoplasm. Immunohistochemically, the tumor cells were positive for anti-epithelial membrane antigen, vimentin, desmin, neuron-specific enolase and WT1 protein antibodies. Similar pathologic features with other small round cell tumors may lead to differential diagnostic difficulties that require the application of ancillary diagnostic methods, such as immunohistochemistry and cytogenetic techniques.

Interleukin-6 gene expression in peripheral blood mononuclear cells from patients undergoing hemodialysis or continuous ambulatory peritoneal dialysis

To compare the interleukin-6 (IL-6) gene expression in the peripheral blood mononuclear cells (PBMCs) and plasma IL-6 levels in patients undergoing continuous ambulatory peritoneal dialysis (CAPD) with those in patients undergoing hemodialysis. Eleven hemodialysis patients, 10 CAPD patients, 15 non-dialyzed patients with end-stage kidney disease (ESKD), and 7 healthy controls were included in this study. PBMCs were collected by differential centrifugation. Plasma IL-6 concentration was measured by enzyme immunoassay. Plasma IL-6 levels were significantly increased in the hemodialysis and CAPD patients as compared with non-dialyzed ESKD patients and normal subjects (p < 0.01). Following hemodialysis, plasma IL-6 levels exceeded those before hemodialysis. No significant difference was found in plasma IL-6 levels in CAPD patients and in hemodialysis patients when blood was drawn before hemodialysis. Low but steady-state levels of IL-6 mRNA expression were observed in the non-dialyzed ESKD patients. The expression of IL-6 mRNA in PBMCs was significantly increased in the patients undergoing hemodialysis or CAPD as compared with the non-dialyzed ESKD patients. The PBMC IL-6 mRNA was significantly lower in CAPD patients than in hemodialysis patients (p < 0.01). A significant correlation was found between the plasma concentration of IL-6 and the expression of IL-6 mRNA in PBMCs from patients undergoing hemodialysis or CAPD (p < 0.01). The hemodialysis or CAPD procedure contributed to the increase in PBMC IL-6 mRNA expression and plasma IL-6 concentration. CAPD treatment stimulated the production of IL-6 to a lesser extent than hemodialysis treatment.

The urinary podocyte as a marker for the differential diagnosis of idiopathic focal glomerulosclerosis and minimal-change nephrotic syndrome

BACKGROUND/AIMS

Detection of podocytes in the urine sediment of children indicates that severe podocyte injury occurred in the glomerulus. Focal glomerulosclerosis (FGS) and minimal-change nephrotic syndrome (MCNS) are kidney diseases characterized by massive proteinuria. The aim of the present study was to determine whether urinary podocytes can be detected in patients with idiopathic FGS or MCNS and whether immunosuppression therapy alters these cells.

METHODS

Twenty patients with MCNS (nephrotic stage, n = 12; remission stage, n = 8), 15 patients with FGS and 20 healthy controls were included in the present study. Urinary podocytes were stained by immunofluorescence. All patients with MCNS at the nephrotic stage received prednisolone for 6 months, and all patients with FGS received some form of immunosuppression therapy including prednisolone, cyclophosphamide or mizoribine for 12 months.

RESULTS

The 12 nephrotic-stage MCNS patients achieved remission after treatment. Seven of the 15 FGS patients also achieved remission, but the other 8 remained in the nephrotic stage. Urinary podocytes were not detected in any patient with MCNS nor were they detected in healthy controls. Urinary podocytes were detected in all FGS patients (mean, 4.2 cells/ml) before treatment and the number of cells decreased in the 7 patients who achieved remission. The number of podocytes was unchanged in the other 8 patients even after treatment.

CONCLUSION

Urinary podocytes may be a useful diagnostic indicator for differentiation between FGS and MCNS. These cells may also mark disease progression in cases of FGS.

Polymyxin b-immobilized fiber reduces increased plasma endothelin-1 concentrations in hemodialysis patients with sepsis

We studied whether plasma endothelin (ET)-1 concentrations are altered in patients with septic shock who are undergoing hemodialysis and whether polymyxin B-immobilized fiber (PMX-F) treatment affects on these concentrations. Fifteen hemodialysis patients with septic shock treated with PMX-F (group A), 10 such patients who received conventional treatments (group B), 20 hemodialysis patients without septic shock (group C) and 20 healthy controls (group D) were included in this study. Plasma ET1 levels were measured by radioimmunoassay and endotoxin levels were determined by endospecy test. The survival rate in group A (67%) was higher than that in group B (30%). Blood endotoxin levels decreased significantly from 36.4+/-8.2 pg/mL to 10.6+/-3.8 pg/mL (p < 0.01) after PMX-F treatment in group A. The pretreatment plasma ET-1 levels in patients in group A (58.6+/-9.8 pg/mL) and group B (56.8+/-7.8 pg/mL) were significantly higher than those in group C (p < 0.01) and group D (p < 0.001). Plasma ET-1 levels in group C (11.2+/-3.2 pg/mL) were higher than those in group D (2.6+/-0.6 pg/mL) (p < 0.01). Plasma ET-1 levels following hemodialysis (10.9+/-3.0 pg/mL) were not altered significantly compared with those before hemodialysis. Plasma ET-1 levels decreased significantly in group A after PMX-F treatment (11.4+/-3.6 pg/mL) (p < 0.01); the levels in group B were not altered after conventional treatment. Our data suggest that ET-1 may be associated with septic shock in patients undergoing hemodialysis and that PMX-F is effective in reducing plasma ET-1 levels in these patients.

Positive regulation of skeletal myogenesis by R-Ras

Most of the proteins in the Ras-family proteins, including Ras, Rap and TC21, have been reported to be strong inhibitors of skeletal myogenesis. Here we show that R-Ras, another member of this family, promotes terminal differentiation of C2C12 skeletal myoblasts. In contrast to Ras, which induced a markedly transformed phenotype of C2C12 cells, an activated mutant of R-Ras (R-RasQ87L) did not exhibit any inhibitory effect on the differentiation of C2C12 cells, but enhanced the formation of multinucleated myotubes. Although R-RasQ87L showed little effect on induction of two muscle-specific proteins, creatine kinase and myogenin, it prevented cell death during myoblast differentiation, probably through Akt activation and Bcl-xL induction. Motility of C2C12 cells, which may be involved in fusion of myoblasts, was also stimulated by R-RasQ87L. Furthermore, we observed a transient activation of endogenous R-Ras during differentiation of C2C12 cells. The ectopic expression of R-Ras GAP inhibited the differentiation. These results suggest that R-Ras has a positive effect on the terminal differentiation of myoblasts and may be involved in the program of skeletal myogenesis.

Formation of the Ras dimer is essential for Raf-1 activation

Although it is well established that Ras requires membrane localization for activation of its target molecule, Raf-1, the reason for this requirement is not fully understood. In this study, we found that modified Ras, which is purified from Sf9 cells, could activate Raf-1 in a cell-free system, when incorporated into liposome. Using a bifunctional cross-linker and a protein-fragmentation complementation assay, we detected dimer formation of Ras in the liposome and in the intact cells, respectively. These results suggest that dimerization of Ras in the lipid membrane is essential for activation of Raf-1. To support this, we found that, when fused to glutathione S-transferase (GST), unprocessed Ras expressed in Escherichia coli could bypass the requirement for liposome. A Ras-dependent Raf-1 activator, which we previously reported (Mizutani, S., Koide, H., and Kaziro, Y. (1998) Oncogene 16, 2781-2786), was still required for Raf-1 activation by GST-Ras. Furthermore, an enforced dimerization of unmodified oncogenic Ras mutant in human embryonic kidney (HEK) 293 cells, using a portion of gyrase B or estrogen receptor, also resulted in activation of Raf-1. From these results, we conclude that membrane localization allows Ras to form a dimer, which is essential, although not sufficient, for Raf-1 activation.

Elevation of serum levels of metalloproteinase-1, tissue inhibitor of metalloproteinase-1 and type IV collagen, and plasma levels of metalloproteinase-9 in polycystic kidney disease

Several studies on polycystic kidney disease (PKD) have revealed a number of extracellular matrix (ECM) abnormalities, suggesting that an abnormal ECM plays a role in the development of tubular cysts. Cystic kidney tubules synthesize and secrete high levels of metalloproteinases (MMP), which may participate in the restructuring of the tubular basement membrane. The aim of the present study was to determine whether serum MMP-1, tissue inhibitor of metalloproteinase (TIMP)-1, and type IV collagen levels, and plasma MMP-9 levels were altered in patients with PKD. Sixteen patients with autosomal dominant polycystic kidney disease, and 20 healthy controls were included in this study. Specific enzyme immunoassays were used to measure MMP-1, MMP-9, TIMP-1, and type IV collagen levels. Serum MMP-1 (14.8 +/- 3.6 ng/ml), TIMP-1 (288.6 +/- 48.6 ng/ml), and type IV collagen (192.6 +/- 38.8 ng/ml) concentrations, and plasma MMP-9 (90.2 +/- 26.8 ng/ml) concentrations in patients with PKD were significantly higher than those in healthy controls (MMP-1; 6.6 +/- 0.9 ng/ml, p < 0.01, MMP-9; 36.4 +/- 12.2 ng/ml, p < 0.01, TIMP-1; 164.6 +/- 22.8 ng/ml, p < 0.01, and type IV collagen; 86.6 +/- 14.2 ng/ml, p < 0.001). The present results suggest that ECM abnormalities associated with cystic kidney may result from aberrant degradation as well as from abnormal synthesis of ECM components.

Novel mutations and genotype-phenotype relationships in 107 families with Fukuyama-type congenital muscular dystrophy (FCMD)

Fukuyama-type congenital muscular dystrophy (FCMD), one of the most common autosomal recessive disorders in the Japanese population, is characterized by congenital muscular dystrophy in combination with cortical dysgenesis (micropolygyria). Recently, we identified, on chromosome 9q31, the gene responsible for FCMD, which encodes a novel 461 amino acid protein which we have termed fukutin. Most FCMD-bearing chromosomes examined to date (87%) have been derived from a single ancestral founder, whose mutation consisted of a 3 kb retrotransposal insertion in the 3' non-coding region of the fukutin gene. FCMD is the first human disease known to be caused primarily by an ancient retrotransposal integration. We under-took a systematic analysis of the FCMD gene in 107 unrelated patients, and identified four novel non-founder mutations in five of them: one missense, one nonsense, one L1 insertion and a 1 bp insertion. The frequency of severe phenotypes, including Walker-Walberg syndrome-like manifestations such as hydrocephalus and microphthalmia, was significantly higher among probands who were compound heterozygotes carrying a point mutation on one allele and the founder mutation on the other, than it was among probands who were homozygous for the 3 kb retrotransposon. Remarkably, we detected no FCMD patients with non-founder (point) mutations on both alleles of the gene, and suggest that such cases might be embryonic-lethal. This could explain why few FCMD cases are reported in non-Japanese populations. Our results provided strong evidence that loss of function of fukutin is the major cause of FCMD, and appeared to shed some light on the mechanism responsible for the broad clinical spectrum seen in this disease.

Plasma, urinary, and erythrocyte concentrations of guanidino compounds in patients with chronic renal failure

Guanidino compounds are among the most likely candidates for uremic toxins. We determined the plasma, erythrocyte, and urinary concentration of guanidino compounds in 30 hemodialysis patients and 15 patients with chronic renal failure who had not undergone hemodialysis. Guanidino compounds were measured by high-performance liquid chromatography. Plasma levels of taurocyamine, guanidinosuccinic acid, alpha-N-acetyl-L-arginine, creatine, guanidinobutyric acid, guanidine, and methylguanidine were significantly increased in patients with chronic renal failure with or without hemodialysis. In contrast, plasma guanidinoacetic acid concentrations were significantly decreased. Erythrocyte concentrations of creatinine, guanidinosuccinic acid, guanidine and methylguanidine were also markedly elevated. No correlation was observed between plasma creatinine concentration and erythrocyte concentration of guanidinosuccinic acid or methylguanidine. However, there was a significant correlation between plasma and erythrocyte methylguanidine, and between plasma and erythrocyte guanidinosuccinic acid.

[A case of acute renal failure with rhabdomyolysis caused by the interaction of theophylline and clarithromycin]

Theophylline toxicity has been recognized since its introduction into clinical medicine. Clarithromycin is a new oral macrolide antibiotic with excellent antibacterial activity and rare adverse effect. Patients with upper respiratory infection are often treated with theophylline and clarithromycin concurrently. We report a case of acute renal failure due to acute rhabdomyolysis caused by the interaction of theophylline and clarithromycin. A 72-year-old man visited our hospital because of coughing and a sore throat continuing for 1 week. He was diagnosed as having the common cold with a bronchial asthmatic symptom and was prescribed 200 mg/day of sustained-release theophylline for the treatment of asthma for 7 days. One week later, he visited our hospital again. Radiographic study of the chest revealed mild interstitial pneumonia and 200 mg/day of sustained-release theophylline and 400 mg/day of clarithromycin were administrated concomitantly. Five days after the second visit, the patient was admitted to our hospital because of generalized twitching, muscular weakness, high fever and serious general condition. He experienced generalized muscular twitching and tremor. Blood urea nitrogen was 106.1 mg/dl, serum creatinine was 7.4 mg/dl, serum creatinine kinase (CK) was 36,000 IU/l (normal 15-130 IU/l), CK isozyme revealed the following ratio: BB 0%, MB 1% and MM 99%. He was diagnosed as having acute renal failure with rhabdomyolysis caused by the interaction of theophylline and clarithromycin. Hemodialysis therapy was started. After 5 weeks, his serum creatinine was markedly decreased. It is well-known that clarithromycin enhances the serum concentration of theophylline by inhibition of the cytochrome P450-dependent pathway in hepatocytes. Theophylline toxicity may be enhanced when clarithromycin is administrated concomitantly, especially to elderly patients with dehydration.

Treatment with polymyxin B-immobilized fiber reduces platelet activation in septic shock patients: decrease in plasma levels of soluble P-selectin, platelet factor 4 and beta-thromboglobulin

OBJECTIVE

To clarify whether plasma concentrations of soluble P-selectin, platelet factor-4 (PF-4) and beta-thromboglobulin (betaTG) are altered in patients with septic shock and whether polymyxin B-immobilized fiber (PMX-F) treatment affects these changes.

SUBJECTS

Thirty patients with septic shock who were treated with PMX-F (group A), 20 such patients who received conventional therapies (group B) and 20 healthy control subjects(group C).

METHODS

ELISA using commercial kits. Endotoxin elimination by direct hemoperfusion using PMX-F.

RESULTS

Blood endotoxin levels decreased significantly from 49.4+/-8.8 pg/ml to 13.0+/-4.5 pg/ml after PMX-F treatment. The pretreatment plasma concentrations of soluble P-selectin, PF-4 and betaTG in patients in groups A and B were significantly higher than those in group C (p<0.001). Plasma concentrations of these factors decreased significantly in group A after PMX-F treatment (p<0.01); however, the concentrations in group B were not altered after conventional treatment. The survival rate of group A (60%) was higher than that of group B (30%).

CONCLUSIONS

Our findings suggest that soluble P-selectin, PF-4 and betaTG may be associated with septic shock and that PMX-F is effective in reducing these markers in patients with septic shock.

Gene therapy for renal anemia in mice with polycystic kidney using an adenovirus vector encoding the human erythropoietin gene

BACKGROUND

Recombinant human erythropoietin (rHuEPO) is primarily used for patients with anemia associated with end-stage renal disease. We evaluated the efficacy of EPO gene therapy using adenovirus vector for chronic renal failure mice expressing severe renal anemia.

METHODS

Recombinant HuEPO gene transfer to mesothelial cells was performed in vitro and in vivo. Recombinant replication-deficient adenoviruses containing rHuEPO cDNA (AdCMVEPO), E. coli lacZ gene (AdCMVlacZ), or an nonexogenous gene (AdNull as control vector) driven by the cytomegalovirus promotor/enhancer were constructed. The oligosaccharides associated with the rHuEPO from AdCMVEPO-treated mesothelial cells were analyzed. For in vivo study, the DBA/2FG-pcy mouse, a model for human autosomal recessive polycystic kidney disease resulting in chronic renal failure with progressive anemia, was used.

RESULTS

The sialylated oligosaccharides associated with the rHuEPO produced in AdCMVEPO-treated mesothelial cells occupied 78 +/- 0.7% of the total oligosaccharide pool. A single intraperitoneal administration of AdCMVEPO induced rHuEPO synthesis in the peritoneal cells and a marked increase in erythrocyte production. The maximal increase in hematocrit (43 +/- 4%) was observed on day 28, and it remained elevated for 40 days.

CONCLUSION

These results indicate that intraperitoneal administration of AdCMVEPO improves renal anemia in mice with chronic renal failure and that the mesothelial cell is an appropriate target cell for gene transfer.

Effect of hemoperfusion with polymyxin B-immobilized fiber on plasma endothelin-1 and endothelin-1 mRNA in monocytes from patients with sepsis

Hemoperfusion using polymyxin B-immobilized fiber (PMX-F) is reported to be an effective treatment for sepsis. The aim of the present study is to assess whether plasma endothelin-1 (ET-1) and ET-1 messenger RNA (mRNA) levels in peripheral-blood monocytes are altered in patients with sepsis and whether PMX-F treatment affects plasma ET-1 and monocyte ET-1 mRNA levels. Sixteen patients with sepsis and 20 healthy volunteers were included in this study. Plasma ET-1 concentration was measured by radioimmunoassay (RIA), and plasma levels of transforming growth factor-beta (TGF-beta), tumor necrosis factor-alpha (TNF-alpha), and interleukin-1beta (IL-1beta) were measured by enzyme-linked immunosorbent assay (ELISA). Sixteen patients with sepsis were treated with direct hemoperfusion using PMX-F columns. Blood endotoxin levels decreased significantly from 35 to 10 pg/mL after two treatments of direct hemoperfusion, each for 2 hours. Patients with sepsis showed significantly increased levels of plasma ET-1 (P < 0.001) and monocyte ET-1 mRNA (P < 0.001) compared with healthy volunteers. However, no differences in plasma levels of TGF-beta, TNF-alpha, and IL-1beta existed between patients with sepsis and healthy volunteers. Increased plasma ET-1 levels and monocyte ET-1 mRNA levels in patients with sepsis decreased significantly after PMX-F treatment (P < 0.01). These data suggest that the secretion of ET-1 from peripheral-blood monocytes may be stimulated by endotoxin, and PMX-F treatment may be effective in reducing ET-1 secretion in patients with sepsis.

Modulation of plasma metalloproteinase-9 concentrations and peripheral blood monocyte mRNA levels in patients with septic shock: effect of fiber-immobilized polymyxin B treatment

The authors measured plasma metalloproteinase (MMP)-9 and corresponding monocyte mRNA in 20 patients with septic shock. Plasma MMP-9 concentrations and monocyte MMP-9 mRNA levels were significantly higher in the 10 nonsurviving patients with septic shock than in 10 surviving patients and 25 normal controls. Hemoperfusion using polymyxin B immobilized on fibers (PMX-F), a reportedly effective treatment for septic shock, was studied for effects on MMP-9 in the patients. Increases in plasma MMP-9 concentrations and corresponding monocyte mRNA levels were attenuated significantly by PMX-F treatment in both nonsurviving and surviving patients. These data suggest that plasma MMP-9 concentrations and monocyte MMP-9 mRNA levels may be useful prognostic markers in septic shock, and that PMX-F treatment affects MMP-9.

Changes in plasma erythropoietin and interleukin-6 concentrations in patients with septic shock after hemoperfusion with polymyxin B-immobilized fiber

OBJECTIVE

To find out whether polymyxin B-immobilized fiber (PMX-F) treatment affects the clinical parameters and plasma concentrations of erythropoietin (EPO) and interleukin (IL)-6.

DESIGN

A prospective case series study.

SETTING

Intensive care unit of the Department of Internal Medicine, Misato Junshin Hospital, Saitama, and Koto Hospital, Tokyo, Japan.

PATIENTS

17 consecutive patients (10 men, 7 women; mean age 54.6 years) with clinically defined septic shock and 20 healthy volunteers (12 men, 8 women; mean age 52.2 years).

MAIN RESULTS

Of the 17 patients with septic shock, 9 (53 %) survived. The systolic blood pressure increased significantly from 78+/-6 to 106+/-8 mm Hg 2 h after PMX-F treatment in patients with septic shock. Plasma endotoxin levels decreased significantly after treatment, from 40+/-6 to 12+/-4 pg/ml. The pretreatment plasma concentrations of EPO and IL-6 were significantly higher in the 8 nonsurviving patients with septic shock (EPO: 400+/-36 mlU/ml; IL-6: 6260+/-1180 pg/ml) than in the 9 surviving patients (EPO: 120+/-22 mlU/ml; IL-6: 680+/-138 pg/ml) and the 20 control subjects (EPO, 12+/-6 mlU/ml; IL-6, 8+/-2 pg/ml). Plasma concentrations of EPO and IL-6 in patients with septic shock decreased significantly after PMX-F treatment (EPO, nonsurviving: 320+/-28 mlU/ml, p < 0.05; survivors: 26+/-8 mlU/ ml, p < 0.001; IL-6, nonsurviving: 3860+/-840 pg/ml, p < 0.01; survivors: 84+/-20 pg/ml, p < 0.001).

CONCLUSIONS

Plasma concentrations of EPO and IL-6 may be prognostic indicators in patients with septic shock: PMX-F treatment may be effective in reducing the plasma concentrations of EPO and IL-6 in patients with septic shock.

Expression of cysteine proteinases and their inhibitor, cystatin beta, in cultured rat mesangial cells

Matrix expansion in the glomerular mesangial area is observed in diabetic nephropathy. Intracellular breakdown of long-lived proteins was lower in mesangial cells in the high glucose medium than that in the control medium. Enzymatic activity of cathepsin L increased 1.4-fold after 6 h of treatment with the high glucose, and then declined gradually to 72% of control cells after treatment for 36 h. Change in the enzyme activity of cathepsin B showed a similar time course but less magnitude than that of cathepsin L. Immunoblot analysis with anti-cathepsin L antibody showed that change in the enzyme activity of cathepsin L was due to the change in the amount of cathepsin L, and that with anti-cathepsin B antibody showed no change in the amount of cathepsin B in the mesangial cells treated with high glucose. Intracellular cathepsin activities were controlled not only by the amounts but also by the inhibitor cystatin beta. Immunoblot analysis with anti-cystatin beta antibody showed that intracellular levels of cystatin beta increased slightly after 24 h of treatment with high glucose. These changes were derived from changes in mRNA level. These results, therefore, demonstrated that the decrease of intracellular protein breakdown in mesangial cells treated with high glucose medium was due to both suppression of cathepsins and increase of cystatin beta.

Effects of hemoperfusion with polymyxin B-immobilized fibre on serum neopterin and soluble interleukin-2 receptor concentrations in patients with septic shock

OBJECTIVE

the aim of the present study was to determine whether serum neopterin and soluble interleukin (IL)-2 receptor levels were related to the development of septic shock and whether polymyxin B-immobilized fibre (PMX-F) treatment affects these levels.

METHODS

we examined 24 patients admitted to our intensive care unit with Gram-negative septic shock. Serum neopterin and soluble IL-2 receptor levels were measured using commercially available test kits. Patients were treated with direct hemoperfusion using PMX-F columns.

RESULTS

fifteen out of 24 patients (63%) survived and were discharged from our hospitals within 30 days after PMX-F treatment. Blood endotoxin levels decreased significantly from 49.2+/-8.6 pg/ml to 13.2+/-4.4 pg/ml after PMX-F treatment. The pretreatment serum concentrations of neopterin and IL-2 receptor were significantly higher in the nine non-surviving patients with septic shock than in the 15 surviving patients (P<0.01) and 20 control subjects (P<0.001). Serum concentrations of neopterin and IL-2 receptor in patients with septic shock decreased significantly after PMX-F treatment (P<0.01).

CONCLUSIONS

these data suggest that serum neopterin and IL-2 receptor concentrations may be prognostic indicators in patients with septic shock. PMX-F treatment may be effective for reducing serum neopterin and IL-2 receptor concentrations.

Synergistic action of R-Ras and IGF-1 on Bcl-xL expression and caspase-3 inhibition in BaF3 cells: R-Ras and IGF-1 control distinct anti-apoptotic kinase pathways

R-Ras and insulin-like growth factor-1 (IGF-1) synergistically inhibit apoptosis of BaF3 cells upon interleukin-3 deprivation. To characterize the mechanism of this synergistic inhibition, we examined the effect of R-Ras and IGF-1 on several apoptosis-related proteins. Extracellular signal-regulated kinase (ERK) was activated by IGF-1, but not by R-Ras. In contrast, Akt was activated strongly by R-Ras, but weakly by IGF-1. It was also found that R-Ras and IGF-1 cooperatively induced Bcl-xL expression and inhibited caspase-3 activation.