RES-701-2, -3 and -4, novel and selective endothelin type B receptor antagonists produced by Streptomyces sp. I. Taxonomy of producing strains, fermentation, isolation, and biochemical properties

RES-701-2, -3 and -4, novel cyclic peptide endothelin antagonists, were isolated from the culture broths of Streptomyces sp. RE-701 and RE-896, RES-701s selectively inhibited the ET-1 binding to endothelin type B receptor (ETB receptor) with IC50 values ranging from 5 to 20 nM. Taxonomy of the producing strains, fermentation, isolation and biochemical properties of RES-701s are described.

[Usefulness of endotoxin-specific limulus test for the measurement of endotoxin in cerebrospinal fluid in diagnosis of bacterial meningitis]

Using a new endotoxin-specific chromogneic limulus assay (Endoscopy test), endotoxin concentrations were measured in 93 specimens of cerebrospinal fluid (CSF) from 66 pediatric patients. Eighteen patients were diagnosed as having menigitios. Of these, 6 cases (group A) with gram-negative meningitis proven by culture had high CSF endotoxin concentrations of 115.3, (82-133) (median, range) pg/ml. Ten cases (group B) with gram-positive or aseptic meningitis had endotoxin concentrations of 2.15 (0.1-3.6) pg ml. Other 2 cases with bacterial meningitis (group C), in whom no pathogen was detected, had CSF endotoxin concentrations of more than 100 pg/ml. Four cases with encephalitis (group D) and 45 cases with non-meningitis or non- encephalitis (group E), had CSF endotoxin concentrations of less than 5 pg/ml. Despite a negative culture after antibiotic treatment in group A patients, endotoxin was cleared slowly from the CSF. A clearing of endotoxin from CSF was followed by alleviation of fever with a more gradual decline in CRP values. In 2 cases of group C, the negative bacterial culture appeared to be attributable to the previous treatment with antibiotics. However, these patients had high CSF endotoxin levels, indicating gram negative bacterial meningitis. In 17 CSF specimens from 5 patients of group A, in whom Haemophilus influenzae was detected on admission, an additional a latex agglutination test for the detection of H. influenzae polysaccharide antigen was performed. Only 3 specimens from 3 patients with CSF endotoxin concentrations of more than 80 pg/ml had a positive agglutination test. These results suggest that quantitation of endotoxin concentrations is useful for the diagnosis of gram-negative meningitis. And also, the clearance of endotoxin from CSF during treatment appears to be useful in determining the timing of when antibiotic should be stopped.

Blood levels of endothelin-1 and thrombomodulin in patients with disseminated intravascular coagulation and sepsis

We evaluated the roles of plasma endothelin-1 and plasma thrombomodulin in the development of disseminated intravascular coagulation (DIC) in patients with sepsis. Plasma endothelin-1 was measured by radioimmunoassay (RIA). Plasma thrombomodulin and tumor necrosis factor-alpha (TNF-alpha) were measured by enzyme-linked immunosorbent assay (ELISA), and serum protein C (protein C) was measured by the synthetic substrate method. Endotoxin was measured by the Endospecy test, a synthetic substrate method. A new perchloric acid method was used for the pretreatment of plasma. Blood levels of endothelin-1 and thrombomodulin were significantly higher in patients with DIC than in those without DIC (p < 0.0001). Endothelin-1 and thrombomodulin levels were positively correlated (r = 0.8645, p = 0.0001), as were endothelin-1 and TNF-alpha levels (r = 0.5441, p = 0.0002). Thrombomodulin and protein C levels were negatively correlated (r = -0.5627, p = 0.0001). Endotoxin was elevated above the normal level 14.3% (6/42) for these patients. TNF-alpha is involved in the production of endothelin-1 and thrombomodulin, which play a role in the pathogenesis of DIC and whose blood levels reflect its severity.

[Characterization of prostate cancer, benign prostatic hyperplasia and normal prostates using endorectal 1H magnetic resonance spectroscopy]

BACKGROUND

We evaluate the usefulness of 1H endorectal resonance spectroscopy to characterize prostate pathology.

METHODS

With an endorectal surface coil we have studied 20 individuals with normal (1), benign hyperplastic (9) and malignant (10) prostates.

RESULTS

The major findings of our studies were that the patients with cancer have a significantly lower citrate-to-choline ratio (cit/cho) and creatin-to-choline ratio (cre/cho) than the patients with BPH (p < 0.05). There is well correlation between cit/cho and gland-to-stroma ratio of the BPH tissue as well as histological grade of the cancer tissue. 1H spectroscopy offers the advantages of differential diagnosis between benign and malignant prostates. We, however, failed to demonstrate cancer in 2 cases; the lesion was too small in one case, and out of the region of interest in the other. It is necessary that the foci in the prostate is at least 1.5 X 1.5 X 1.5 cm3 of the volume in order to obtain genuine spectrogram of carcinoma.

CONCLUSION

Endorectal 1H magnetic resonance spectroscopy can characterize metabolic differences between the normal and malignant prostate.

A useful testing strategy in phase III trials: combined test of superiority and test of equivalence

A useful testing strategy is proposed for a confirmatory phase III clinical trial. It consists of a combined test of superiority and test of equivalence, and it is easy to apply. By introducing the strategy, we can perform a post hoc analysis in a confirmatory experiment. Thus a more flexible decision will be possible than the usual single testing method provides. It is shown that the procedure needs no adjustment for multiplicity from the point of view of the closed testing procedure. The relationship between this strategy and a confidence interval is also discussed.

Inhibition of vitamin D3-induced cell differentiation by interferon-gamma in HL-60 cells determined by a nitroblue tetrazolium reduction test

The combined effects of 1 alpha,25-dihydroxyvitamin D3 [1,25(OH)2D3] and interferon-gamma (IFN-gamma) or tumor necrosis factor alpha (TNF-alpha) on cell differentiation in HL-60 human promyelocytic leukemia cells were examined by a nitroblue tetrazolium (NBT) reduction test. 1,25(OH)2D3 at the concentrations of 7-70 nM induced NBT-positive cells, which was used as a criterion of cell differentiation. IFN-gamma itself showed little effect on induction of NBT-positive cells or on cell growth at a concentration up to 1000 U/ml. However, in a combination of 1,25(OH)2D3 with IFN-gamma (100 and 300 U/ml), cell differentiation was strongly inhibited and was accompanied by growth inhibition. Treatment with a combination of 1,25(OH)2D3 and TNF-alpha or IFN-gamma and TNF-alpha showed an additive effect on cell differentiation. IFN-gamma seems to act as a specific inhibitor for 1,25(OH)2D3-induced cell differentiation. To elucidate the cause of the inhibition of cell differentiation by IFN-gamma, the ability of the cells to produce superoxide (O2-) was examined after culture for 5 days in the presence of 1,25(OH)2D3 and IFN-gamma. The results indicated that the inhibition of IFN-gamma was caused by a reduction in the ability of the cells to produce O2- in response to stimulation by 12-O-tetradecanoylphorbol-13-acetate (TPA).

Long-term high-colloid oncotic therapy for ischemic brain edema in gerbils

BACKGROUND AND PURPOSE

We evaluated the effects of long-term administration of high-colloid oncotic pressure on ischemic brain edema in Mongolian gerbils.

METHODS

Animals that exhibited stroke after 35 minutes of unilateral forebrain ischemia were used. The gerbils were divided into albumin- (1 g/kg body wt, 25% albumin; n = 30) and saline-injected (4 mL/kg; n = 30) groups. Both agents were administered intravenously every 12 hours starting immediately after the recirculation. Plasma colloid oncotic pressure, serum sodium and potassium concentrations, and brain water, sodium, and potassium content were measured 24, 48, and 72 hours after recirculation.

RESULTS

Plasma colloid oncotic pressure at 24, 48, and 72 hours after recirculation was significantly higher in the albumin- (26.1 +/- 2.3 mm Hg) than in the saline-treated group (18.5 +/- 1.9 mm Hg; P < .01), and brain water content of the ischemic hemisphere was significantly lower in the albumin group (79.5%, 80.2%, and 80.5%, respectively) than in the saline group (80.9%, 81.6%, and 82.1%, respectively; P < .05) at all three time points. Brain sodium content at 24 hours was significantly lower in the albumin than in the saline group (P < .05), while brain potassium content at 24 and 48 hours was significantly higher in the albumin than in the saline group (P < .05). The changes in brain water and sodium plus potassium content, which were calculated from differences between the ischemic and nonischemic hemispheres, showed a significant correlation in both groups (P < .01), but there was no significant difference between the linear regression lines for both groups.

CONCLUSIONS

Long-term high-colloid oncotic pressure was effective in treating ischemic brain edema, probably acting by diminishing the bulk flow through the disrupted blood-brain barrier and ameliorating the vasogenic edema.

Beta-sarcoglycan (A3b) mutations cause autosomal recessive muscular dystrophy with loss of the sarcoglycan complex

The dystrophin associated proteins (DAPs) are good candidates for harboring primary mutations in the genetically heterogeneous autosomal recessive muscular dystrophies (ARMD). The transmembrane components of the DAPs can be separated into the dystroglycan and the sarcoglycan complexes. Here we report the isolation of cDNAs encoding the 43 kD sarcoglycan protein beta-sarcoglycan (A3b) and the localization of the human gene to chromosome 4q12. We describe a young girl with ARMD with truncating mutations on both alleles. Immunostaining of her muscle biopsy shows specific loss of the components of the sarcoglycan complex (beta-sarcoglycan, alpha-sarcoglycan (adhalin), and 35 kD sarcoglycan). Thus secondary destabilization of the sarcoglycan complex may be an important pathophysiological event in ARMD.

Analysis of time-dependent change of Escherichia coli F1-ATPase activity and its relationship with apparent negative cooperativity

Except for the case of gradual activation of EF1 (F1-ATPase from Escherichia coli) caused by the dissociation of the epsilon subunit [Laget, P. P. and Smith, J. B. (1979) Arch. Biochem. Biophys. 197, 83-89], EF1 has long been thought not to show a time-dependent change in activity [Senior, A.E. et al. (1992) Arch. Biochem. Biophys. 297, 340-344]. Here, we report the time-dependent inactivation and activation of EF1, which are apparently similar to those of mitochondrial F1-ATPases [Vasilyeva, E.A. et al. (1982) Biochem. J. 202, 15-23]. Analysis of these changes as a function of ATP concentrations in relation to negative cooperativity revealed that the initial inactivation phase was attributable to the decrease in the Vmax associated with the low Km (around 10 microM), and the following activation, probably due to the dissociation of the epsilon subunit, corresponded to the increase in the Vmax associated with the high Km (in the order of 100 microM). Thus, the time-dependent change in EF1 activity is closely related to the apparent negative cooperativity (multiple Km values) of ATP hydrolysis.

A histologically distinctive interstitial pneumonia induced by overexpression of the interleukin 6, transforming growth factor beta 1, or platelet-derived growth factor B gene

Interstitial pneumonia is characterized by alveolitis with resulting fibrosis of the interstitium. To determine the relevance of humoral factors in the pathogenesis of interstitial pneumonia, we introduced expression vectors into Wistar rats via the trachea to locally overexpress humoral factors in the lungs. Human interleukin (IL) 6 and IL-6 receptor genes induced lymphocytic alveolitis without marked fibroblast proliferation. In contrast, overexpression of human transforming growth factor beta 1 or human platelet-derived growth factor B gene induced only mild or apparent cellular infiltration in the alveoli, respectively. However, both factors induced significant proliferation of fibroblasts and deposition of collagen fibrils. These histopathologic changes induced by the transforming growth factor beta 1 and platelet-derived growth factor B gene are partly akin to those changes seen in lung tissues from patients with pulmonary fibrosis and markedly contrast with the changes induced by overexpression of the IL-6 and IL-6 receptor genes that mimics lymphocytic interstitial pneumonia.

Mucopolysaccharidosis type VI in rats: isolation of cDNAs encoding arylsulfatase B, chromosomal localization of the gene, and identification of the mutation

Mucopolysaccharidosis (MPS) type VI, the lysosomal storage disorder caused by the deficiency of arylsulfatase B (ARSB) activity, occurs in humans, cats, and rats. To characterize the molecular lesion(s) causing MPS VI in rats, cDNAs encoding rat ARSB were isolated from a rat liver cDNA library. The nucleotide and deduced amino acid sequences of rat ARSB had approximately 80 and 85% identity with the human ARSB sequences, respectively. The chromosomal location of the rat ARSB gene was determined by PCR analysis of rat-mouse somatic cell hybrid panel. The ARSB gene was assigned to rat chromosome 2, where the locus for the MPS VI phenotype in rats has been localized by linkage analysis. To identify the mutation(s) within the ARSB gene causing MPS VI in rats, the ARSB sequence were amplified from affected animals and completely sequenced. Notably, a homoallelic one-base insertion at nucleotide 507 (507insC) was identified, resulting in a frame shift mutation and premature termination at codon 258. The presence of the insertion completely correlated with the occurrence of the MPS VI phenotype among 66 members of the MPR rat colony. Thus, we conclude that 507insC is the causative mutation in these animals and that the MPS VI rats are an authentic model of human MPS VI.

A case report of mixed P- and C-ANCA positive patients with pauci-immune crescentic glomerulonephritis

We describe 2 patients with pauci-immune crescentic glomerulonephritis and elevated titers of perinuclear and cytoplasmic anti-neutrophil cytoplasmic antibody (P-ANCA and C-ANCA) which were associated with both 29 and 59 kD bands on Western blots. The presence of C-ANCA corresponds with a clinical and/or histological diagnosis of Wegener's granulomatosis, but although both patients suffered from pulmonary complications there was no clinical nor histological evidence of granulomatosis. Transbronchial lung biopsy showed only interstitial pneumonia and old hemorrhage. Therefore, the patients' conditions were interpreted as microscopic polyarteritis nodosa or hitherto undefined vasculitis associated with ANCA.

Plasma endotoxin in typhoid fever

Plasma endotoxin contents of the patients with sepsis or typhoid fever were measured by two sophisticated chromogenic limulus tests; Endospecy and Toxicolor tests. Endospecy test is the endotoxin-specific test and Toxicolor is responsible for both endotoxin and (1,3)-beta-D-glucan. Plasma was pretreated by our new PCA method which resolved the problem as to the detection of a lesser amount of plasma endotoxin when pretreated by the conventional PCA method. Although Toxicolor values have been reported to exceed more than the Endospecy value, under complicated pathophysiological situations, almost all specimens of these patients had a similar value, except in one expired septic shock case. In 18 typhoid fever cases, Salmonella typhi was isolated only from the bile in 5 cases, however endotoxemia occurred in 11 cases (61.1%). Within the first 4 days, the incidence of endotoxemia was higher (10/14, 71.4%). These results suggest that endotoxin assay seemed to be a useful tool for the diagnosis of typhoid fever.

[Role of neutrophils in lung injury after intestinal ischemia and reperfusion in dogs]

We studied the role of neutrophils in lung injury after intestinal ischemia and reperfusion (I/R) in anesthetized dogs with lung lymph fistulae. One group was subjected to 2.5 hours of balloon occlusion of the superior mesenteric artery without laparotomy, followed by 3 hours of reperfusion (I/R group, n = 7). The other group was subjected to the same procedures, except for intestinal I/R (sham operation group, n = 6). In the sham operation group, lung fluid balance, hemodynamics, extravascular water volume (Qw 1: ml/g BFDW), myeloperoxidase activity in the lung (MPO: unit/g DW), H2O2 production by neutrophils in blood (mean DCF/cell), and migration of neutrophils into the lung lymphatic system did not significantly change. In the I/R group, both lung lymph flow (Jv) and protein clearance (Qp) increased more than 2.5 fold as compared with the baseline values, while capillary pressure (Ppc) and the ratio of lymph to plasma protein concentration (CL/Cp) remained almost the same as the baseline values. Qw1 also moderately increased. MPO activity, H2O2 production, and migration of neutrophils into the lung lymphatic system increased after I/R, and were more remarkable than in the sham operation group. These results suggest that activation and migration of primed neutrophils contributes to lung injury after intestinal ischemia and reperfusion.

Methicillin-resistant Staphylococcus aureus: colonization and development of infection in patients with haematological disorders

A retrospective study of 53 patients with haematological disorders whose bacterial cultures were positive for methicillin-resistant Staphylococcus aureus (MRSA), was performed to analyse the risk factors for MRSA infection, and the prognostic factors. Sixteen patients showed colonization by MRSA but never developed infection(C), 16 showed colonization and subsequent infection(C-I), while 21 had MRSA infection at the time of first culture (I). Poor performance status, thrombocytopenia, increased serum urea nitrogen and decreased serum cholinesterase were more prominent in (I) than (C) + (C-I). The risk factors associated with the development of infection from colonization were age and serum cholinesterase. In addition, lower respiratory tract infection as a type of infection, non-remission status of the haematological malignancy and an inappropriate antibiotic therapy were associated with a poor prognosis for MRSA infection.

Application of a new perchloric acid treatment method to measure endotoxin by an endotoxin-specific chromogenic Limulus test in neonatal septicemia

The endotoxin in blood was measured to establish both the cut-off value and to detect Gram-negative septicemia. We employed a new perchloric acid treatment method using an endotoxin-specific chromogenic Limulus test (Endospecy test). The cut-off value of endotoxin in blood was 11.2 pg/mL. All cases of septicemia (n = 7) showed high values of endotoxin. Three cases were Group B streptococci, and two cases were Escherichia coli. The others were showed to be negative in blood cultures. The paired values of endotoxin titers during a 48 h interval were useful to evaluate the effectiveness of antibiotics.

The mechanism of lactitol (NS-4) in inducing adrenomedullary proliferative lesion in rats

We used 13-week repeated oral administration of lactitol as part of a study to clarify the mechanism by which lactitol induces the proliferation of adrenomedullary chromaffin cells. There was a marked increase in urinary calcium (Ca) excretion even though the lactitol administration had no effect on the blood Ca level. A tendency for an increase in adrenal venous blood epinephrine (EPI) and norepinephrine (NE) concentrations was seen. Organ weight measurement of adrenal glands revealed a tendency for an increase in absolute weight and a significant increase in relative weight. Morphometric analysis of adrenomedullary chromaffin cells showed a tendency for an increased total cell volume and a decreased numerical density; but, there was no conspicuous change in the total cell number. Determinations of the anti-bromodeoxyuridine (BrdU) and antiproliferative cell nuclear antigen (PCNA) antibody-positive cell counts showed a tendency for an increased proliferation rate for adrenomedullary chromaffin cells. Electron microscopy showed a slight increase in the number of Golgi apparatuses in these cells. Because the marked increase in urinary Ca excretion was concomitant with morphological changes that suggested the hyperfunction of chromaffin cells in the adrenal medulla and a tendency for an increased cell proliferation rate, we assume that persistent hyperfunction of the adrenomedullary chromaffin cells, which was mediated by enhanced Ca absorption from the intestinal tract, may have induced proliferative lesion.

Expression of the wild-type and the Cys-/Trp-less alpha 3 beta 3 gamma complex of thermophilic F1-ATPase in Escherichia coli

The alpha, beta and gamma subunits of F1-ATPase from thermophilic Bacillus PS3 were expressed in Escherichia coli cells simultaneously in large amounts. Most of the expressed subunits assembled into a form of alpha 3 beta 3 gamma complex in E. coli cells and this complex was easily purified to homogeneity. The recombinant alpha 3 beta 3 gamma complex thus obtained showed similar enzymatic properties to the alpha 3 beta 3 gamma complex obtained by in vitro reconstitution from individual subunits (Yokoyama, K. et al. (1989) J. Biol. Chem. 264, 21837-21841) except that the former had several-fold higher ATPase activity than the latter. Using this expression system, a mutant alpha 3 beta 3 gamma complex with no Trp and Cys was generated by replacing alpha Cys193 and alpha Trp463 with Ser and Phe, respectively. This mutant complex was functionally intact, indicating both residues are not essential for catalysis. The Cys-/Trp-less complex is a convenient 'second wild type' enzyme from which one can generate mutants with Trp (as a fluorescent probe) or Cys (as an acceptor of a variety of probes) at desired positions without concern for 'background' Trp and Cys residues.

HTLV-1 oncoprotein Tax deregulates transcription of cellular genes through multiple mechanisms

Infection of a human retrovirus HTLV-1 induces adult T cell leukemia and a neurological disease, HAM/TSP. Regulatory protein Tax of HTLV-1 is thought to contribute to the pathogenesis. We have studied the mechanism of transcriptional activation induced by Tax protein and identified two independent mechanisms: (a) binding to the enhancer-binding proteins, CREB, CREM, NF-kappa B and SRF, resulting in the activation of these factors through indirect binding to each specific DNA sequence, and (b) binding to I kappa B protein resulting in the suppression of the negative regulator I kappa B, which binds to NF-kappa B. In addition to these factors, a new protein GLI/THP is also involved in the transactivation. On the basis of these mechanisms, gene regulations in vitro and in vivo in HTLV-1-infected cells are discussed.

Acquired von Willebrand disease associated with multiple myeloma; characterization of an inhibitor to von Willebrand factor

Acquired von Willebrand disease (vWD) has been described in a few patients with multiple myeloma. The present study characterizes an inhibitor of von Willebrand factor (vWF) isolated from a patient with multiple myeloma (IgG-kappa). Multimeric analysis of vWF from this patient's plasma showed a reduction in multimers of all sizes. The inhibitor (IgG) detected only the vWF subunit from plasma of normal individuals. It reacted with intact vWF subunit and a 39/34kDa dispase-digested fragment of vWF (residues; Leu480/Val481-Gly718), but did not react with platelet membrane glycoproteins (GPs) or adhesive proteins. The binding of vWF to GPIb mediated by ristocetin and by botrocetin was inhibited by the patient's IgG with an IC50s of 0.3 mg/ml and 0.48 mg/ml, respectively. The platelet aggregation induced by ristocetin or botrocetin was also inhibited by the IgG. These results indicate that this inhibitor may recognize the binding region of vWF to GPIb. Therefore, the antibody to vWF appears to represent the likely pathophysiological mechanism responsible for the acquired vWD in this patient.

Dystrophin-associated proteins in muscular dystrophy

Dystrophin-associated proteins (DAPs) are classified into a few groups, namely, those comprising of dystroglycan complex, sarcoglycan complex, syntrophin complex and others. Subsarcolemmal actin filaments are connected to laminin in the basement membrane through dystrophin and the dystroglycan complex. This system may function to protect muscle fibers from mechanical damage. Furthermore, the sarcoglycan complex is associated with the system. Defects in the components of the protection system or the sarcoglycan complex or both are characteristically found in various muscular dystrophies. The roles of the syntrophin complex are meagerly understood. In this review, the possible roles of laminin, DAPs and dystrophin in each dystrophy are explained.

Correlation between tumor volume doubling time and histologic findings in gastric smooth muscle tumors: clinical implications of tumor volume doubling time

To assess the clinical implications of the tumor volume doubling time of gastric smooth muscle tumors based on a comparison with the histologic findings, seven tumors (four leiomyomas and three leiomyosarcomas) were followed up by consecutive upper gastrointestinal studies between March 1985 and December 1993. The patients were four men and three women with an average age of 58 years (range: 50-71 years). The observation period ranged from 6 to 51 months, with an average of 35 months. All tumors were surgically resected and the histologic diagnosis was confirmed. The following microscopic features were evaluated: 1) mitotic rate, 2) nuclear atypia, and 3) cellularity. Each tumor was also evaluated for the presence or absence of necrosis, hemorrhage, and degeneration. The doubling time ranged from 5 to 27 months with a mean of 16 months. There was a strong negative correlation between the mitotic rate and the doubling time (r = -0.935, P = 0.0019). The doubling time was also significantly related to nuclear atypia, but the number of tumors studied was so small that its reliability was questionable. The doubling time was not related to any other histologic findings. This study shows that the doubling time is useful for estimating the malignant potential of gastric smooth muscle tumors, and that tumors with a doubling time of 16 months or less should be considered as malignant.