Clinical Effect of Recombinant Human Erythropoietin on Anemia Associated with Chronic Renal Failure. A Multiinstitutional Study in Japan

Clinical effect and safety of recombinant human erythropoietin (r-HuEPO) were evaluated in 66 hemodialysis patients with intractable anemia. Initially, 50U/kg dry weight (DW) of r-HuEPO was administered intravenously at the end of every hemodialysis procedure for 4 weeks, then the dosage was increased to 100 and 200U/kg DW for poor responders. The patients’ hematocrits rose from 19.8 ± 2.3% (pretreatment) to 30.2 ± 4.9% after 12 weeks. From 206 U of blood transfusion requirement in the 3-month period before the study, only 34 U were needed after treatment. Serum iron and ferritin levels fell significantly during the study, and iron storage was considered to be one of the decisive factors in the response to r-HuEPO. Blood pressure rose in the course of r-HuEPO administration, but uncontrollable hypertension was rarely observed. There was no significant adverse effect of r-HuEPO except for this mild hypertension. These results indicate that r-HuEPO is an excellent therapeutic aid for the anemia associated with chronic renal failure.

Successful treatment of cytomegalovirus enteritis after unrelated allogeneic stem cell transplantation by the infusion of ex vivo-expanded CD4+ lymphocytes derived from the recipient's peripheral blood donor cells

Adoptive immunotherapies have been developed for antiviral agent-refractory cytomegalovirus (CMV) disease after stem cell transplantation (SCT). However, the application of such strategies is limited, particularly in terms of need for donor cooperation regarding blood sampling and inaccessibility in the setting of cord blood transplantation. Herein, we describe the first successful treatment of antiviral agent-refractory CMV enteritis after allogeneic SCT by the infusion of ex vivo-expanded donor-derived CD4(+) lymphocytes obtained from the recipient's peripheral blood.

Incidence of therapy-related leukemia following chemoradiotherapy for esophageal cancer

e15663

Background: The combination of chemotherapy and concurrent radiotherapy (CRT) has recognized as a curative alternative for several stage of esophageal cancer. On the other hands, a sufficiently long survival time has increased treatment-related late toxicities. However, the frequency and the pathogenesis of secondary malignancies that is the most serious late-onset complication are still unclear. Methods: From July 2000 to March 2008, 348 patients with esophageal squamous cell carcinoma underwent CRT. All patients received chemotherapy consisting with nedaplatin (80 mg/m2, div day1) and fluorouracil (700 mg/m2, ci day 1–5) and concurrent long T field irradiation (2 Gy daily, up to 30 Gy). A hundred patients received a single course as the neoadjuvant setting. Two cycles of CRT as the definitive or palliative setting were administered in 248 patients. Median and average follow-up durations are 8 and 21 months (1 to 92), respectively. Results: Four patients, who achieved CR after CRT, developed leukemia. Case1, 60-yo-male, developed overt acute myeloid leukemia (AML) from myelodysplastic syndrome 48 months after CRT. Cytogenetic analysis showed complicated abnormalities including deletion 5q. Case2, 64-yo-male, developed AML M0 with t(9;22)(q34;q11) 44 months after CRT. Case3, 72-yo-male, developed Burkitt leukemia with t(8;14)(q24;q32) 19 months after CRT. Case4, 65-yo-male, developed myeloid crisis of chronic myelogenous leukemia with complicated abnormalities including t(9;22)(q34;q11) 48 months after CRT. Case 1 and 3 had localized disease and received single course of neoadjuvant CRT. Case 2 and 4 had advance disease and received 2 courses of CRT. All patients eventually died of leukemia. Conclusions: Since platinum and fluorouracil have shown relatively low chance of secondary neoplasm, our data demonstrates that the concurrent radiotherapy which involves massive bone marrow tissue may increase the risk of leukomogenesis. To this end, atypical cytogenetic abnormalities seen in the present cases give a new insight into the biology of therapy-related leukemia. Notably, this is the first report presenting the incidence of secondary leukemia by nedaplatin.

No significant financial relationships to disclose.

Aberrant quality control in the endoplasmic reticulum impairs the biosynthesis of pulmonary surfactant in mice expressing mutant BiP

Accumulation of misfolded proteins in the endoplasmic reticulum (ER) induces the unfolded protein response (UPR), which alleviates protein overload in the secretory pathway. Although the UPR is activated under diverse pathological conditions, its physiological role during development and in adulthood has not been fully elucidated. Binding immunoglobulin protein (BiP) is an ER chaperone, which is central to ER function. We produced knock-in mice expressing a mutant BiP lacking the retrieval sequence to cause a defect in ER function without completely eliminating BiP. In embryonic fibroblasts, the UPR compensated for mutation of BiP. However, neonates expressing mutant BiP suffered respiratory failure due to impaired secretion of pulmonary surfactant by alveolar type II epithelial cells. Expression of surfactant protein (SP)-C was reduced and the lamellar body was malformed, indicating that BiP plays a critical role in the biosynthesis of pulmonary surfactant. Because pulmonary surfactant requires extensive post-translational processing in the secretory pathway, these findings suggest that in secretory cells, such as alveolar type II cells, the UPR is essential for managing the normal physiological ER protein overload that occurs during development. Moreover, failure of this adaptive mechanism may increase pulmonary susceptibility to environmental insults, such as hypoxia and ischemia, ultimately leading to neonatal respiratory failure.

A novel human metalloprotease synthesized in the liver and secreted into the blood: possibly, the von Willebrand factor-cleaving protease?

We identified a novel metalloprotease, which could be responsible for cleaving the Tyr842-Met843 peptide bond of von Willebrand factor (vWF). This metalloprotease was purified from Cohn Fraction-I precipitate of human pooled plasma by the combination of gel filtration, DEAE chromatography, and preparative polyacrylamide gel electrophoresis in the presence of SDS. The NH2-terminal amino acid sequence of the isolated protein was: AAGGILHLELLVAVGPDVFQAHQEDTRRY. Based on this sequence, we searched human genomic and EST databases, and identified compatible nucleotide sequences. These results suggested that this protein is a novel metalloprotease, a member of the family of a disintegrin and metalloprotease with thrombospondin type-1 motifs (ADAMTS), and its genomic DNA was mapped to human chromosome 9q34. Multiple human tissue northern blotting analysis indicated that the mRNA encoding this protease spanned approximately 5 kilobases and was uniquely expressed in the liver. Furthermore, we determined the cDNA sequence encoding this protease, and found that this protease was comprised of a signal peptide, a proregion followed by the putative furin cleavage site, a reprolysin-type zinc-metalloprotease domain, a disintegrin-like domain, a thrombospondin type-1 (TSP1) motif, a cysteine-rich region, a spacer domain, and COOH-terminal TSP1 motif repeats.

An efficient refolding method for the preparation of recombinant human prethrombin-2 and characterization of the recombinant-derived alpha-thrombin

Human recombinant prethrombin-2 was produced in Escherichia coli. The expressed prethrombin-2 formed intracellular inclusion bodies from which the protein was refolded by a simple one-step dilution process in buffer consisting of 50 mM Tris-HCl, containing 20 mM CaCl(2), 500 mM NaCl, 1 mM EDTA, 600 mM arginine, 1 mM cysteine, 0.1 mM cystine, 10% (v/v) glycerol, and 0.2% (w/v) Brij-58 at pH 8.5. After refolding, prethrombin-2 was purified by hirudin-based COOH-terminal peptide affinity chromatography, and then activated with Echis carinatus snake venom prothrombin activator (ecarin). The activated protein, alpha-thrombin, was then tested for several activities including activity toward chromogenic substrate, release of fibrinopeptide A from fibrinogen, activation of protein C, and thrombin-activatable fibrinolysis inhibitor, reactivity with antithrombin, clotting activity, and platelet aggregation. The kinetic data showed no differences in activity between our recombinant alpha-thrombin and plasma-derived alpha-thrombin. The yield of refolded recombinant human prethrombin-2 was about 4-7% of the starting amount of solubilized protein. In addition, the final yield of purified refolded protein was 0.5-1%, and about 1 mg of recombinant prethrombin-2 could be isolated from 1 liter of E. coli cell culture.

Role of human cytochrome P450 3A4 in metabolism of medroxyprogesterone acetate

Medroxyprogesterone acetate (MPA) is a drug commonly used in endocrine therapy for advanced or recurrent breast cancer and endometrial cancer. The drug is extensively metabolized in the intestinal mucosa and in the liver. Cytochrome P450s (CYPs) involved in the metabolism of MPA were identified by using human liver microsomes and recombinant human CYPs. In this study, the overall metabolism of MPA was determined as the disappearance of the parent drug from an incubation mixture. The disappearance of MPA in human liver microsomes varied 2.6-fold among the 18 samples studied. The disappearance of MPA in the same panel of 18 human liver microsomes was significantly correlated with triazolam alpha-hydroxylase activity, a marker activity of CYP3A (r = 0.764; P < 0.001). Ketoconazole, an inhibitor of CYP3A4, potently inhibited the disappearance of MPA in 18 human liver microsomes. Anti-CYP3A antibody also inhibited 86% of the disappearance of MPA in human liver microsomes. Although sulfaphenazole (an inhibitor of CYP2C9) and S-mephenytoin (an inhibitor of CYP2C19) partially inhibited the disappearance of MPA, no effect of the anti-CYP2C antibody was observed. The disappearance of MPA did not correlate with either the activity metabolized via CYP2C9 (diclofenac 4'-hydroxylase activity) or the activity metabolized via CYP2C19 (S-mephenytoin 4'-hydroxylase activity). Among the 12 recombinant human CYPs (CYP1A1, CYP1A2, CYP2A6, CYP2B6, CYP2C8, CYP2C9, CYP2C18, CYP2C19, CYP2D6, CYP2E1, CYP3A4, and CYP3A5) studied, only CYP3A4 showed metabolic activity of MPA. These results suggest that CYP3A4 is mainly involved in the overall metabolism of MPA in human liver microsomes.

Prader-Willi syndrome with elevated follicle stimulating hormone levels and diabetes mellitus

A 21 -year-old man with Prader-Willi syndrome (PWS) was hospitalized due to hyperglycemia. After diet therapy and transient insulin administration, his blood glucose levels improved. Based on the fact that his urinary C-peptide levels increased, the diabetes mellitus may have been due to insulin resistance with obesity. In addition, his testes had become atrophied. Testosterone levels remained low even after human chorionic gonadotropin (HCG) administration. Luteinizing hormone (LH) levels were also low after LH releasing hormone (LHRH) administration. The LH response increased slightly after daily LHRH administration, indicating hypothalamic hypogonadism. Follicle stimulating hormone (FSH) levels were, however, high and increased after LHRH administration. The selective FSH elevation may have been due to the accompanying idiopathic oligospermia.

Isolation and absolute structures of enantiomeric 1,2-bis(4-hydroxy-3-methoxyphenyl)-1,3-propanediol 1-O-glucosides from the bark of Hovenia trichocarpa

Two 1,2-bis(4-hydroxy-3-methoxyphenyl)-1,3-propanediol 1-O-glucosides, hovetrichosides A (1) and B (2), were isolated from the bark of Hovenia trichocarpa. Their structures were established by extensive NMR experiments and chemical methods. Compounds 1 and 2 were (1R), (2S)-1-(4-hydroxy-3-methoxyphenyl)-2-(4-hydroxy-3-methoxyphenyl)-1, 3-propanediol 1-O-beta-D-glucopyranoside and (1S), (2R)-1-(4-hydroxy-3-methoxyphenyl)-2-(4-hydroxy-3-methoxyphenyl)-1, 3-propanediol 1-O-beta-D-glucopyranoside, respectively.

Hovetrichosides C-G, five new glycosides of two auronols, two neolignans, and a phenylpropanoid from the bark of Hovenia trichocarea

Two 2-hydroxy-2-benzylcoumaranone glycosides, 2,4, 6-trihydroxy-2-[(4'-hydroxyphenyl) methyl]-3(2H)-benzofuranone-4-yl-beta-D-glucopyranoside (maesopsin 4-O-glucoside) (1) and 2,4,6-trihydroxy-2-[(4'-hydroxyphenyl) methyl]-3(2H)-benzofuranone-4-yl-beta-D-glucopyranosido-4'-y l-alpha-L -rhamnopyranoside (maesopsin 4-O-glucosido 4'-O-rhamnoside) (2), two neolignan glycosides, 2R-(E)-2, 3-dihydro-2-(4'-hydroxy-3'-methoxylphenyl)-5-(3"-hydroxy-1"-pro pen yl) -7-methoxy-3-benzofuranmethanol-4'-yl-beta-D-glucopyranosyl-(1-->3 )-[ beta-D-glucopyranosyl-(l-->2)]-beta-d-glucopyranoside (3) and (threo) 1-(4'-hydroxy-3'-methoxy)-2-(4"-hydroxymethyl-2", 6"-dimethoxyphenoxy)-propane-1,3-diol-4'-yl-beta-d-glucopynosid e (4), and a phenylpropanoid glycoside, 3-methoxy-5-(2'-propenyl)-1, 2-benzenediol-1-yl-beta-D-apiofuranosyl-(1-->6)-beta-D- glucopyransodie (5) were isolated from the bark of Hovenia trichocarea. Compounds 1-5 were named hovetricosides C-G, respectively, and their structures were established by extensive NMR experiments and chemical methods. Also obtained in this investigation were the known compounds acanthoside B, kelampayoside A, shashenoside I, and 3,4, 5-trimethoxyphenol-1-O-beta-D-xylopyranosyl-(1-->6)-beta-D- glucopyranoside.

Trans-regulation of myogenin promoter/enhancer activity by c-ski during skeletal-muscle differentiation: the C-terminus of the c-Ski protein is essential for transcriptional regulatory activity in myotubes

c-ski gene product is a nuclear protein with myogenesis-promoting and transforming activities. We have analysed the effects of c-ski transfection on the promoter/enhancer activity of the upstream region of the myogenin gene during in vitro myogenesis using CAT reporter assay. When co-transfected with c-ski into myogenic C2C12 cells, promoter/enhancer activity was efficiently suppressed in proliferating cells, but the myogenesis-induced increase in activity was potentiated approximately ten times more (150-fold in the ski-transfected cells) than the ordinary increase (12-fold in the mock) 48 h after induction of differentiation. In non-myogenic 10T1/2 cells, c-ski transfection caused persistent suppression of promoter/enhancer activity in both proliferating and growth-arrested (i.e. myogenesis-inducing) conditions. Thus the ski-dependent potentiation of myogenin gene transcriptional activity appears to be specific for myogenesis. The C-terminal region (amino acids 595-663) of the c-Ski protein was essential for the potentiating activity in myotubes. Other members of the ski-gene family, snoN and snoA, were ineffective in transactivation, possibly because of the defect in the corresponding C-terminal region. c-Ski protein underwent a mobility shift on SDS/PAGE after in vitro myogenesis which may explain the conversion of the activity from suppressive in myoblasts to potentiating in myotubes. Deletion analysis of the upstream region of the myogenin gene revealed that a responsive element to c-ski in myotubes is located at a distinct site upstream of the basal promoter/enhancer region.

A transient increase of snoN transcript by growth arrest upon serum deprivation and cell-to-cell contact

To analyze the possible involvement of c-ski and c-sno during the course of in vitro myogenesis, expression of their transcripts during differentiation of a murine muscle cell line (C2C12) was monitored by competitive reverse transcription-polymerase chain reaction (RT-PCR). The transcripts of c-snoN were temporarily increased 25-fold above basal level at 12 h prior to the onset of transcription of muscle-specific gene, e.g. myogenin and muscle creatine kinase, whereas c-ski was expressed invariably. The transient increase of c-snoN was blocked when myogenesis was interrupted by the presence of fetal calf serum in culture medium, probably due to growth factors being included; basic fibroblast growth factor (b-FGF) blocked the transient increase whereas epidermal growth factor (EGF) did not, consistent with the inhibitory effect of b-FGF and no effect of EGF on myotube formation of C2C12. In fibroblastic C3H10T1/2 cells, snoN exhibited a similar transient increase of transcript when growth arrested under the same conditions as for in vitro myogenesis, indicating that the expression of snoN is not sufficient to induce the onset of muscle differentiation and an unknown factor involved in myogenic cells is necessary. The transient increase of snoN transcript may represent a common entrance step of cells into the G0 phase where muscle differentiation is substantiated, considering that it was observed upon growth arrest of fibroblastic C3H10T1/2 cells and prior to the elevation of MCK in C2C12 but undetected when entry into G0 was blocked by b-FGF.

[Computed tomographical evaluation of diabetic nephropathy]

Diabetic nephropathy can be regarded mainly as a type of microangiopathy, but is a disease that may also include aspects of macroangiopathy. This is especially true of renal disease in non-insulin dependent diabetes mellitus (NIDDM), which is characterized not only by diabetic glomerulosclerosis, but also by atherosclerosis. We performed morphological studies on the kidney, using computed tomography (CT), focusing on such points as: (1) abdominal aortic calcifications at the level of kidney, (2) calcifications in the renal artery, and (3) wedge-shaped defects on the renal surface. We noted that these findings became more prominent in NIDDM patients during end-stage renal failure than during normal renal function, and were significantly more common in those two NIDDM groups than in age-matched nondiabetic patients without hypertension, hyperlipidemia or gout. NIDDM patients exhibited these features more frequently than IDDM patients.

Hyperammonemia in a patient with short bowel syndrome and chronic renal failure

A patient with short bowel syndrome (SBS) and renal failure developed a disturbance of consciousness with hyperammonemia. Abnormally low concentrations of ornithine, citrulline, and arginine were observed on the plasma aminogram. These results suggested that the activities of amino acid synthetase localized in the small intestinal flora were lost. The small intestine is required for arginine synthesis; thus, infusion limited to the essential amino acids to SBS patients will cause a deficiency of the urea cycle intermediates, ornithine, citrulline, and arginine and may lead to hyperammonemia. In addition, the renal insufficiency may have caused decreased excretion of ammonia. In this patient, supplemental arginine improved the symptoms.

Endothelium-dependent relaxation in peripheral vasculature and kidney of non-insulin-dependent diabetes mellitus

Desmopressin (DDAVP), an AVP.V2-receptor agonist, evokes endothelium-dependent relaxation (EDR) due to nitric oxide (NO), EDR factor (EDRF) in the systemic vasculature, and glomerular afferent arterioles via AVP receptor(s). Glyceryl trinitrate (GTN) causes endothelium-independent (nonreceptor-mediated) vasodilation. We elucidated the possible involvement of EDRF in early non-insulin-dependent diabetes mellitus (NIDDM) and glomerular hyperfiltration (GHF) by DDAVP and GTN infusions. Patients with advanced DM nephropathy (DM.Np) (n = 7) were also examined. DDAVP and GTN decreased the mean blood pressure in DM with GHF (DM + GHF) and without GHF (DM-GHF) greater than that in normal subjects (N), without any difference in the heart rate changes in any group. Plasma levels of cGMP, a cellular messenger of NO, were significantly increased by DDAVP and GTN with a similar increment in each group. DDAVP caused a significant increase in urinary cGMP excretion in each group with a similar increment in each group. However, it caused a transient increase in creatinine clearance only in DM + GHF although GTN did not, and an exaggerated excretion of urinary albumin in early NIDDM, especially in DM+GHF, without a change in beta 2-microglobulin excretion. In contrast, in DM.Np GTN caused a decrease in blood pressure and an increase in plasma cGMP levels, but DDAVP did not. In conclusion, in peripheral vasculature and kidney, an enhanced sensitivity of vascular smooth muscle to NO is present in early NIDDM. The exaggerated dilation of glomerular afferent arterioles by preferentially produced NO in in situ, which causes a rise in PGC, might be partly responsible for the glomerular hyperfiltration and subsequently the increase in the glomerular protein permeation of DM+GHF. However, in peripheral blood vessels of DM.Np EDR is impaired. Thus, EDR seems to change with the development of NIDDM.

[Histopathological assessment of renal biopsy specimens of subjects with urine abnormality]

Between April 1985 and April 1992, 25,672 men (age 47 +/- 9 years, mean +/- SD) and 9,791 women (48 +/- 9 years) underwent mass urinalysis in the Center for Adult Complete Physical Examination in our hospital. The results revealed proteinuria in 6.3% of the men and 4.4% of the women and hematuria in 17.4% of the men and 37.8% of the women. Thirty-five subjects with asymptomatic persistent proteinuria and/or hematuria identified as a result of follow-up testing by the nephrologists at our hospital underwent renal biopsy. All of the biopsy specimens obtained were examined by light microscopy, fluorescence microscopy and electron microscopy. Histopathological findings in the biopsy specimens from these 35 subjects were as follows: One case (3%) of chronic pyelonephritis, 11 cases (31%) of IgA nephropathy, 4 cases (11%) of IgA nephropathy (severe type), 5 cases (14%) of membranous nephropathy, 4 cases (11%) of thin basement membrane disease (TMD), 7 cases (28%) of benign nephrosclerosis and 3 cases (9%) of minor glomerular abnormality. Light microscopy, fluorescence microscopy and electron microscopy for histopathological assessment of renal specimens, especially for the diagnosis of TDM, which was not uncommon, were indispensable tools in our study. Moreover, it is essential for proteinuria and hematuria to be tested simultaneously using the same standard method in all the urine specimens collected.

Immunohistochemical study of human advanced glycosylation end-products (AGE) in chronic renal failure

In patients with diabetic renal failure plasma advanced glycosylation end-products (AGE) levels are reported to be elevated and dialyzer of continuous ambulatory peritoneal dialysis (CAPD) is usually used with a high glucose concentration. Here, an immunohistochemical study on human AGE accumulation in vascular beds and peritonea of patients with chronic renal failure (CRF) or those on CAPD was undertaken. Further, the influence of aging was studied using AGE-specific monoclonal antibody. 1. AGE accumulation was observed in radial arterial walls (from vascular intima to smooth muscle layer) of diabetic patients with CRF. Even in some non-diabetic patients with CRF (n = 3/6), especially in those with a long history of CRF and dialysis treatment, similar positive staining was seen in vascular walls. No AGE staining was observed in any renal tissue of age-matched control subjects including tissue from patients with acute renal failure. 2. Although AGE accumulation was not seen in the peritonea of CRF patients with no prior CAPD therapy, it was seen in the mesothelial layers and in adjacent coarse connective tissues of peritonea from patients on CAPD (n = 6), even from as early as only 3 months of CAPD therapy. 3. AGE accumulation was observed in the vascular bed of the non-diabetic aged kidney with normal function, but not in that of the young kidney. Thus, AGE accumulation in the vascular bed may depend on the degree and term of renal impairment and on aging in addition to diabetes. AGE accumulation in the peritonea became positive following CAPD treatment, indicating that it might affect the efficiency of CAPD.

Brefeldin A inhibits muscle-specific gene expression during differentiation in C2C12 myoblasts

In analyzing regulatory mechanisms underlying differentiation-dependent expression of muscle proteins, we have found that mouse C2C12 myoblast cells treated with Brefeldin A (BFA), which specifically blocks the intracellular transport of protein from endoplasmic reticulum (ER) to the Golgi apparatus, failed to differentiate. BFA reversibly inhibited myotube formation at a threshold concentration of 1.0 micrograms/ml. The same concentration of BFA completely blocked accumulation of secretory proteins, e.g., fibronectin into the culture medium, probably due to retention in ER. Interestingly, the induction of muscle creatine phosphokinase (MCK) activity was sensitive to BFA, although a constitutive expression of lactate dehydrogenase, one of the cytosolic housekeeping enzymes, was resistant to BFA. In the kinetic analysis of MCK induction, translation of existing MCK mRNA was not inhibited by BFA since MCK activity became resistant to BFA once levels of MCK transcript accumulated. The differentiation-dependent accumulation of MCK transcript was also suppressed by BFA treatment to approximately 30% of control, although neither general transcriptional activity in vivo nor stability of existing mRNAs was affected even in the presence of BFA. Moreover, induction of muscle regulatory genes, MyoD1 and myogenin, which are upstream of the MCK gene, were inhibited at their transcription level by BFA. Such an effect on muscle regulatory gene transcription by BFA suggests that transport of some factor(s) to the cell surface may be a prerequisite for the muscle-specific gene expression upon differentiation of C2C12 myoblasts.

Role of AVP in the regulation of vascular tonus and blood pressure in patients with chronic renal failure

This study was undertaken to estimate the role of AVP in the regulation of vascular tonus and blood pressure, at first, during hemodialysis hypotension and, secondly, in hypertensive patients with chronic renal failure (CRF). Study 1: among 12 patients with hemodialysis (HD) hypotension showing similar metabolic and endocrine changes except plasma AVP during HD, 6 who showed an increase in plasma AVP after HD were hemodynamically examined during HD. Gradual decreases in mean BP and cardiac index, and increases in systemic vascular resistance (SVR) and plasma AVP, with a slight time-delay, were observed and thereafter BP inversely showed a slight increase at the end of HD, whereas no significant change in HR was found throughout HD. However, the % change in SVR had a positive correlation with % change in plasma AVP levels (P < 0.01, r = 0.559), but not with that in plasma renin activity or plasma norepinephrine levels. Study 2: oral administration of 100 mg of AVP.V1-receptor antagonist, OPC21268, which completely inhibited the vasoconstriction induced by the exogenously administered AVP, did not show any changes in BP and HR of seven hypertensive CRF patients. However, OPC21268 results in a marked decrease in BP of one hypertensive CRF patient with congestive heart failure (CHF) and nephrotic syndrome. Therefore, in some patients with HD hypotension showing impaired SNS and RAS, AVP may play an important role in the maintenance of BP during HD, predominantly via its peripheral vasoconstrictive action. On the other hand, AVP might not aggressively participate in hypertension of CRF patients, even with relatively high levels of plasma AVP.(ABSTRACT TRUNCATED AT 250 WORDS)

Transitional expression of neural cell adhesion molecule isoforms during chicken embryonic myogenesis

The neural cell adhesion molecule, NCAM, is known to be expressed in chicken muscle as at least three principal molecular forms (molecular masses of 155 kDa, 145 kDa, and 120 kDa). They are generated from a single gene by alternative splicing. To distinguish these molecular species and to investigate their expressions in muscle differentiation during chicken embryonic development, we prepared antipeptide antibodies against three different domains of the NCAM. The antibody named MSD<+> was designed to detect muscle-specific domain (MSD) which was inserted into a muscle-specific NCAM by alternative splicing. The locus encompassing the MSD insertion site was detected with the antibody named MSD<->, and cytoplasmic sites near the transmembrane region were detected with the antibody named CYT. Immunoblot analysis utilizing the peptide antibodies prepared here revealed that, of three NCAMs, two isoforms, 155 kDa and 120 kDa, were recognized with the antibody MSD<+> and the same 155-kDa and the other 145-kDa molecule were recognized with the antibody CYT. The antibody MSD<-> was capable of detecting all three isoforms of the NCAM. Expression of the 120-kDa form with MSD but lacking a cytoplasmic tail increased but that of the 145-kDa form with cytoplasmic tail but lacking MSD declined during embryonic day 5 to day 18. The 155-kDa form NCAM with both MSD and cytoplasmic tail was expressed specifically and transiently during embryonic day 11 to day 14 in chick muscle; this period coincides with the period of extensive myotube formation. Thus, this largest isotype seems to play an important role in muscle differentiation.

Endothelium-dependent vasorelaxation evoked by desmopressin and involvement of nitric oxide in rat aorta

It is known that in vivo administration of desmopressin (DDAVP; a selective V2-vasopressin receptor agonist) results in prostacyclin-independent vasodilation. The in vitro effects of DDAVP and its mechanisms were examined using rat aortic strips. DDAVP from a concentration of 1 x 10(-9) M caused a concentration-dependent relaxation of the aorta precontracted with norepinephrine (10(-7) M) with intact endothelium. However, no relaxation was induced in aorta with the endothelium removed. The DDAVP-induced relaxation was not influenced by the presence of indomethacin but was inhibited by L-NG-monomethyl-L-arginine (L-NMMA), a specific inhibitor of nitric oxide (NO) synthesis. The inhibition by L-NMMA was reversed by the addition of L-arginine but not D-arginine. Further, the endothelium-dependent relaxation due to DDAVP was potentiated by superoxide dismutase, a scavenger of superoxide anions, and was inhibited by hemoglobin. DDAVP induced an increase in guanosine 3',5'-cyclic monophosphate levels in the aorta with endothelium but not in aorta without endothelium, and this was suppressed by L-NMMA and hemoglobin. The suppression by L-NMMA was also partially reversed by L-arginine but not by D-arginine. Two selective V2-receptor antagonists had no effect on the DDAVP-induced vasorelaxation. Selective V1-receptor antagonists (a peptidic and a nonpeptidic) caused a concentration-dependent but nonparallel shift to the right of the concentration-response curves to DDAVP. However, DDAVP did not affect the tension of the strip with or without endothelium in nonprecontracted aorta.(ABSTRACT TRUNCATED AT 250 WORDS)

Nafamostat mesilate: a regional anticoagulant for hemodialysis in patients at high risk for bleeding

107 hemodialysis patients at high risk for intradialytic bleeding due to previous surgery or active bleeding from other sites were treated with nafamostat mesilate (FUT-175; FUT) as hemodialysis anticoagulant for 2 weeks. In contrast to heparin. FUT prolonged clotting times only in the extracorporeal circuit. Clotting times were not prolonged even at the conclusion of the treatment, and bleeding from the puncture site after removal of the needle was shorter than with heparin. The exacerbation of bleeding by hemodialysis was noted in only 21 out of 573 hemodialysis procedures (3.7%), and 134 of 145 hemodialysis procedures (92.4%) with active bleeding were successfully completed without increasing the bleeding. Adverse effects of FUT were noted in only 6 cases (5.6%) or 1.2% of HD procedures. These results indicate that FUT is a very useful anticoagulant for HD, especially in patients with high risk of bleeding.

Changes of enzyme activity levels in red blood cells in hemodialysis patients by recombinant human erythropoietin

In a phase II clinical trial to test the ability of recombinant human erythropoietin (r-HuEPO) to reverse the anemia of patients undergoing hemodialysis, the changes of enzyme activity in red blood cells were evaluated in 5 hemodialysis anemic patients who were treated with r-HuEPO. Concerning the activity levels measured, the following conclusions are drawn. 1) HK, ALD, TPI, G6PD and 6PGD were statistically significantly increased at the time when the hematocrit has risen by 8% with the use of r-HuEPO. 2) The enzyme activity levels of PFK, GA3PD, MPGM, ENOL, PK, GR and ADA were higher than normal already before the r-HuEPO treatment. 3) The increases of HK and G6PD by r-HuEPO, as age dependent enzymes, may reflect the generation of young red blood cells. 4) In view of the fact that they are related to ATP production in the glycolysis cycle, we infer that increases of red blood cell enzymes by r-HuEPO may play at least some part in bringing a sensation of "well-being" to severely anemic patients undergoing hemodialysis.

Cervical discs are most susceptible to beta 2-microglobulin amyloid deposition in the vertebral column

Intervertebral discs of 41 chronic renal failure autopsy cases were examined histologically and immunohistochemically to assess the distribution of beta 2-microglobulin-associated (beta 2m) amyloid in the vertebral column. The results demonstrated beta 2m amyloid to appear first in the cervical discs, then in the lumbar and upper thoracic discs, and finally in the middle and lower thoracic discs as the dialysis period is prolonged. The shortest dialysis period for which beta 2m amyloid was detected was one year and seven months. Deposition of beta 2m amyloid was most remarkable in the C4-5, 5-6, and 6-7 levels, which are known to sustain severe mechanical stress in daily life. Thus it is suggested that local mechanical stress accelerates beta 2m amyloidosis. A marked macrophage reaction was observed around the amyloid in cases of severe amyloidosis, the macrophages themselves being immunohistochemically positive for IL-1 beta and TNF-alpha. Amyloid deposition and reactive inflammation mediated by cytokines appear to be closely related to the pathogenesis of destructive spondyloarthropathy.

[Inflammatory cell infiltration around beta 2-microglobulin amyloid deposition: histologic comparison of beta 2-microglobulin amyloidosis with AA or AL amyloidosis]

Thirty-one autopsy cases of beta 2-microglobulin (beta 2M) amyloidosis were pathologically investigated in comparison with 17 autopsy cases of AA or AL amyloidosis. In 20 cases (65%, 20/31) of beta 2M amyloidosis, inflammatory cells, mainly macrophages were seen infiltrating around beta 2M amyloid in intervertebral disks. The more beta 2M amyloidosis advances, the more macrophage infiltration tends to be prominent. In cases of severe beta 2M amyloidosis, the cytoplasm of macrophages around amyloid deposition were swollen with engulfed amyloid substance and were often transforming to foreign body multinucleated giant cells. In addition, granulation tissue was formed with infiltrating macrophages, foreign body multinucleated giant cells, capillary proliferation and fibrosis around beta 2M amyloid deposition. On the other hand, inflammatory cell infiltration around amyloid deposition was scarcely seen in AA or AL amyloidosis. Ultrastructurally, macrophages were abundant in phagocytic vacuoles containing amyloid fibrils. These macrophages were immunohistochemically positive for CD68, IL-1 beta and TNF-alpha. Thus, macrophage infiltration around beta 2M amyloid is thought to be responsible for local pain and tissue destruction of dialysis patients.

Beta 2-microglobulin amyloidosis in hemodialysis patients. An autopsy study of intervertebral disks and posterior longitudinal ligaments

Ninety-five autopsy cases of chronic renal failure, which had or had not been treated by hemodialysis, were examined histologically and immunohistochemically for evidence of amyloid deposition in the intervertebral disks and posterior longitudinal ligaments of the spine. beta 2-Microglobulin (beta 2M) amyloid was not present in non-dialyzed patients with chronic renal failure. In cases showing beta 2M amyloid deposition, the shortest term of hemodialysis was 2 years and 5 months. The incidence of beta 2M amyloidosis tended to increase as the dialysis period was prolonged. An inverse correlation was present between dialysis period and age in 22 cases showing beta 2M amyloid deposition (correlation coefficient: -0.43, p less than 0.05), and beta 2M amyloidosis tended to occur earlier in elderly patients than in younger patients. This suggests that elderly patients are more susceptible to beta 2M amyloidosis. beta 2M amyloid was absent in all of 8 cases of systemic lupus erythematosus which were treated by dialysis for periods ranging from 2 days to 12 years. In these patients, beta 2M amyloidosis may have been prevented by steroids, which had been administered for long periods in all cases. Another amyloid of unknown composition was also frequently present in the intervertebral disks and posterior longitudinal ligaments not only in patients with chronic renal failure but also control patients without chronic renal failure. This amyloid was immunohistologically negative for beta 2M, amyloid A protein, light chain kappa or lambda, prealbumin, and apolipoprotein A-II.

[Clinico-pathological evaluation of mesangial IgA deposition of minimal change with nephrotic syndrome]

The case of IgA glomerulonephritis that shows minimal change with nephrotic syndrome is unusual. Thirteen patients of mesangial IgA deposition of minimal change with nephrotic syndrome (IgAMCNS) are discussed in comparison with twenty patients of non IgA deposition of minimal change with nephrotic syndrome (MCNS). On a common basis of hematuria, two groups are undistinguished. On a reaction pattern to steroid treatment, the former is based on IgA nephritis and the latter is based on minimal change with nephrotic syndrome. There is no difference in light microscopical findings between the two groups. Electron microscopically, the former suggests IgA nephritis and the latter suggests minimal change with nephrotic syndrome. In immunofluorescence, the former group is rare to show typical IgA glomerulonephritis. In conclusion, IgAMCNS is considered to be nephrotic syndrome with asymptomatic IgA deposit in mesangium.

Clinical effect of recombinant human erythropoietin on anemia associated with chronic renal failure. A multi-institutional study in Japan

Clinical effect and safety of recombinant human erythropoietin (r-HuEPO) were evaluated in 66 hemodialysis patients with intractable anemia. Initially, 50U/kg dry weight (DW) of r-HuEPO was administered intravenously at the end of every hemodialysis procedure for 4 weeks, then the dosage was increased to 100 and 200U/kg DW for poor responders. The patients' hematocrits rose from 19.8 +/- 2.3% (pretreatment) to 30.2 +/- 4.9% after 12 weeks. From 206 U of blood transfusion requirement in the 3-month period before the study, only 34 U were needed after treatment. Serum iron and ferritin levels fell significantly during the study, and iron storage was considered to be one of the decisive factors in the response to r-HuEPO. Blood pressure rose in the course of r-HuEPO administration, but uncontrollable hypertension was rarely observed. There was no significant adverse effect of r-HuEPO except for this mild hypertension. These results indicate that r-HuEPO is an excellent therapeutic aid for the anemia associated with chronic renal failure.