Inhibition of Vpr-induced cell cycle abnormality by quercetin: a novel strategy for searching compounds targeting Vpr

Vpr, an accessory gene product of HIV-1 which induces cell cycle abnormality leading to the increased HIV replication, is supposed to be a possible target for anti-AIDS drugs. We recently established a cell line (MIT-23) in which Vpr-induced cell cycle perturbation could be manipulated by a tetracycline promoter. Here, we screened anti-Vpr activity in 27 kinds of herb drugs using MIT-23 cells. One of the extracts prepared from Houttuyniae herba showed an inhibitory activity. Quercetin (QCT), a compound of this crude drug, efficiently inhibited Vpr function without affecting its expression. Furthermore, data suggested that Vpr-induced transcription from HIV-LTR was considerably abrogated by QCT. These data indicate that QCT, a flavonoid previously reported to inhibit HIV replication, also targets Vpr, implicating that MIT-23 cell provides a novel strategy for screening compounds possessing anti-Vpr activity which would be in turn utilized for clarifying the mechanism of Vpr function.

A high-copy-number plasmid capable of replication in thermophilic cyanobacteria

A 2.5 kb high-copy-number plasmid, pMA4 in thermophilic cyanobacterium Synechococcus sp. MA4 was isolated and characterized to develop a genetic engineering system for thermophilic cyanobacteria. The copy number of pMA4 was determined to be by densitometry about 350/cell. The pMA4 may be a type of rolling-circle plasmid, because a possible rep gene encoding 34 kD-protein and a consensus sequence of a double-stranded origin nick site of rolling circle plasmids were found in the pMA4 sequence. The pMA4 was electro-introduced into another thermophile, Synechococcus sp. MA19, which is the strongest poly-beta-hydroxybutyrate (PHB) accumulator in photoautotrophic organisms. The pMA4 was incorporated and retained in MA19. These results indicate that pMA4 could be developed as a useful vector for thermophilic cyanobacteria.

[Histopathology of thrombotic vascular diseases]

Three principal factors predispose to thrombus formation (Virchow's triad): (1) endothelial injury, (2) stasis or turbulence of blood flow, and (3) blood hypercoagulability. Endothelial denudation is the most important factor, especially in the development of arterial thrombus. Arterial thrombi are frequently occlusive, and the most common sites are coronary, cerebral, and femoral arteries. The thrombi induce severe ischemia or infarction of the heart, brain, and lower extremities. The thrombi are usually superimposed on an atherosclerotic plaque. Plaque rupture or erosion is considered to be the trigger of acute thrombus formation. While venous thrombi are invariably occlusive, and commonly affect the lower extremities. Static blood flow, phlebitis, and genetic and acquired hypercoagulability often contribute to venous thrombosis.

Adenovirus-mediated local expression of human tissue factor pathway inhibitor eliminates shear stress-induced recurrent thrombosis in the injured carotid artery of the rabbit

The main cause of acute coronary syndrome may be recurrent thrombosis, which is initiated by the activation of the extrinsic coagulation pathway. Tissue factor (TF) pathway inhibitor (TFPI) efficiently inhibits an early step in this pathway by the formation of a complex with factor VIIa, TF, and factor Xa. We determined whether local TFPI gene transfer can inhibit thrombosis in an injured artery without inducing systemic side effects. Balloon-injured rabbit carotid arteries were infected with an adenoviral vector that expressed either human TFPI (AdCATFPI) or bacterial beta-galactosidase (AdCALacZ). Two to 6 days after gene transfer, thrombosis was induced by the production of constant stenosis of the artery, and blood flow was measured continuously with an electromagnetic flow probe. A cyclic flow variation, which is thought to reflect the recurrent formation and dislodgment of mural thrombi, was observed in all AdCALacZ-infected arteries as well as in saline-infused arteries. In contrast, no cyclic flow variation was detectable in AdCATFPI-transfected arteries, even in the presence of epinephrine (1 microg. kg-1. min-1 infusion). Prothrombin time, activated partial thromboplastin time, and the ex vivo platelet aggregation induced by either adenosine diphosphate or collagen were unaltered in AdCATFPI-infected rabbits. We found that in vivo TFPI gene transfer into an injured artery completely inhibits the recurrent thrombosis induced by shear stress even in the presence of catecholamine, without affecting systemic coagulation status. Adenovirus-mediated local expression of TFPI may have the potential for the treatment of human thrombosis.

Immobilization of P450 monooxygenase and chloroplast for use in light-driven bioreactors

P450 monooxygenases exhibit great potential for application to bioreactors for the decomposition of various hydrophobic chemicals including pollutant compounds. P450-containing microsomes were immobilized in spinach chloroplasts for use in light-driven bioreactors. We tested three methods (entrapment, adsorption and cross-linking) to immobilize chloroplasts and yeast microsomes containing a genetically engineered fusion enzyme between rat P450 1A1 and yeast P450 reductase. Entrapment in agarose gave the best activity for the conversion of 7-ethoxycoumarin to 7-hydroxycoumarin under illumination of 6200 lx. We then tested three light-driven bioreactors (two column-type and one batch-type reactors developed) using the immobilized gels. A two-phase column-type reactor with separately immobilized microsomes and chloroplasts showed a higher conversion rate than a reactor with co-immobilization of both components. The reactor showed a turnover rate of 6.32 mol product/mol P450/min after a 40-min run, and 2.49 after a 180-min run. These turnover rates are higher than the values reported by others using immobilized microsomal P450s.

Photosynthetic accumulation of poly-(hydroxybutyrate) by cyanobacteria--the metabolism and potential for CO2 recycling

Regulatory mechanism in PHB [poly-(hydroxybutyrate)] accumulation by cyanobacteria, especially by a thermophilic isolate, Synechococcus MA19 was reviewed in comparison with a genetically engineered strain. The strain, MA19 accumulates PHB under nitrogen starved and photoautotrophic conditions (MA19-N). Little PHB synthase activity was detected in crude extracts from the cells grown in nitrogen sufficient conditions (MA19 + N). The activity was detected exclusively in membrane fractions from MA19 + N. The change of the enzyme activity was insensitive to chloramphenicol, which suggests post-translational activation. In vitro, acetyl phosphate activated PHB synthase in membrane fractions from MA19 + N, and the extent of activation depended on the concentration of acetyl phosphate. Phosphotransacetylase which catalyzes the conversion of acetyl-CoA to acetyl phosphate was detected in crude extracts from MA19-N but not in those from MA19 + N. These results suggested that intracellular acetyl phosphate concentration could be controlled, depending on C-N balance and intracellular acetyl-CoA concentration. On the contrary, in genetically-engineered cyanobacterium (transformant with PHB synthesizing genes from Ralstonia eutropha), it did not seem to be PHB synthase but acetyl-CoA flux that limits PHB synthesis. The closer association of PHB granules with thylakoid membranes in MA19 is suggested than that in the genetically-engineered cyanobacterium, which may reflect the difference of distribution of PHB synthase. Transposon-mutagenesis was used to acquire mutants of its altered PHB regulatory mechanism. PHA production by cyanobacteria was considered from the aspects of photobioreactors.

Nitric oxide is the predominant mediator for neurogenic vasodilation in porcine pial veins

The innervation pattern and the vasomotor response of the potential transmitters in the porcine pial veins were investigated morphologically and pharmacologically. The porcine pial veins were more densely innervated by vasoactive intestinal polypeptide (VIP)- and neuropeptide Y-immunoreactive (I) fibers than were calcitonin gene-related peptide (CGRP)-I, choline acetyltransferase-I, Substance P (SP)-I, and NADPH diaphorase fibers. Serotonin (5-HT)-I fibers, which were not detected in normal control pial veins, were observed in isolated pial veins after incubation with 5-HT (1 microM). 5-HT-I fibers, however, were not observed when incubation with 5-HT was performed in the presence of guanethidine (1 microM), suggesting that 5-HT was taken up into the sympathetic nerves. In vitro tissue bath studies demonstrated that porcine pial veins in the presence of active muscle tone relaxed on applications of exogenous 5-HT, CGRP, SP, VIP, and sodium nitroprusside, whereas exogenous norepinephrine and neuropeptide Y induced only constrictions. Transmural nerve stimulation (TNS) did not elicit any response in pial veins in the absence of active muscle tone. However, in the presence of active muscle tone, pial veins relaxed exclusively on TNS. This tetrodotoxin-sensitive relaxation was not affected by receptor antagonists for VIP, CGRP, 5-HT, or SP but was blocked by L-glutamine (1 mM) and abolished by Nomega-nitro-L-arginine (10 microM) and Nomega-nitro-L-arginine methyl ester (10 microM). The inhibition by L-glutamine, Nomega-nitro-L-arginine, and Nomega-nitro-L-arginine methyl ester was reversed by L-arginine and L-citrulline but not by their D-enantiomers. These results demonstrate that the vasomotor effect of all potential transmitters except 5-HT in the pial veins examined resembles that in cerebral arteries. Although porcine pial veins receive vasodilator and constrictor nerves, a lack of constriction on TNS suggests that the dilator nerves that release nitric oxide may play a predominant role in regulating porcine pial venous tone.

[Smooth muscle myosin of SM1 and SM2 isoforms expressing human neuroblastoma cell line of MP-N-MS]

Human neuroblastoma (NB) cell lines have at least three morphological appearance of neuroblastic (N-type), substrate-adhessive (S-type) and intermediate(I) cells. Our previous study revealed S-type cells expressed alpha-smooth muscle actin, desmin and/or basic-calponin, indicating the plausible smooth muscle cell characteristics of S-type cells. In this study, a new human NB cell line, MP-N-MS, was established from bone marrow metastasis of a one year and six-month old girl with advanced NB, originating from right adrenal gland. Morphology of this cell line is composed of S-type cells. MP-N-MS was identified as a NB cell line by surface membrane antigen analysis and MYCN gene amplification. EWS-FLI1 and EWS-ERG chimeric products, observed in Ewing family tumors, were not detected by RT-PCR (reverse transcriptase-polymerase chain reaction). In cytoskeletal protein analysis, alpha-smooth muscle actin and basic calponin of smooth muscle cell markers were detected. Furthermore, smooth myosin of SM1 isoform was identified in MP-N-MS cell line by immunofluorescence, Western blot and RT-PCR, whereas smooth myosin of SM2 was detected by RT-PCR. MP-N-MS is the first cell line, showing SM1 and SM2 isoforms. The presence of smooth muscle myosin of SM1 and SM2 isoforms in MP-N-MS demonstrated the mature smooth muscle phenotype of this NB cell line, and the ability of NB cells to differentiate into smooth muscle cell.

Inhibitory effect of erythromycin on interleukin-8 secretion from exudative cells in the nasal discharge of patients with chronic sinusitis

OBJECTIVES

The mechanism of the efficacy of long-term low-dose macrolide therapy for chronic sinusitis is not fully understood. The authors studied the inhibitory effect of erythromycin on interleukin-8 (IL-8) secretion from exudative cells in the nasal discharge of patients with chronic sinusitis.

STUDY DESIGN AND METHODS

Exudative cells in the nasal discharge were isolated from six patients with nonallergic chronic sinusitis. The cells, more than 90% of which were neutrophils, were incubated with or without erythromycin in the presence of 10 micrograms/mL of lipopolysaccharide. The IL-8 concentrations in the culture supernatants were measured by enzyme-linked immunoassay.

RESULTS

The amount of secreted IL-8 in the absence of erythromycin was 682 +/- 226 pg/10(6) cells/24 h. The IL-8 secretion was significantly reduced to 66 +/- 15% and 46 +/- 13% of the control in the presence of 10(-6) and 10(-5) M of erythromycin, respectively.

CONCLUSION

Erythromycin may act as a biologic modulator that inhibits IL-8 secretion from exudative cells and thereby blocks the vicious circle of neutrophil recruitment and IL-8 generation in the inflammatory site in chronic sinusitis.

Minoxidil increases 17 beta-hydroxysteroid dehydrogenase and 5 alpha-reductase activity of cultured human dermal papilla cells from balding scalp

Minoxidil is known to induce hair growth in male pattern baldness, for which development androgen plays a central role. We studied the effect of minoxidil on testosterone metabolism by cultured dermal papilla cells from balding or nonbalding scalp and dermal fibroblasts. In all three groups, 17beta-hydroxysteroid dehydrogenase activity was much higher than 5alpha-reductase activity. Minoxidil increased 17beta-hydroxysteroid dehydrogenase activity by nearly 40% (P < 0.001) in dermal papilla cells of balding scalp, whereas the effect was less marked in dermal papilla cells from nonbalding scalp and dermal fibroblasts. 5alpha-Reductase activity was also slightly increased by minoxidil in dermal papilla cells from balding scalp. Again, the effect on 5alpha-reductase activity was insignificant in the other two groups of cells. Whether such modification of testosterone metabolism in dermal papilla cells of balding scalp by minoxidil is related to its therapeutic effect remains unknown.

Cell density of adrenomedullin-immunoreactive cells in the gastric endocrine cells decreases in antral atrophic gastritis

AIMS

Adrenomedullin (AM) is a novel hypotensive and vasorelaxing peptide recently isolated from human phaeochromocytoma tissue, and is widely distributed in various organs. In this study we examined the localization of AM-immunoreactive (IR) cells in the gastric mucosa and AM-IR cell density in antral atrophic gastritis.

METHODS AND RESULTS

Gastric mucosal tissues were taken from the gastric body and antral mucosa of 52 patients (27 men, 25 women; mean age 56.0 (range 20-86) years). Immunohistochemical analysis revealed that AM-IR cells were present in the pyloric glands, but not in the fundic glands, and that AM-IR cells were stained positively for chromogranin A and gastrin. The percentage of AM-IR cells vs chromogranin A- and gastrin-IR cells was 42 and 56%, respectively. The number of AM-IR cells decreased with the progression of severity of atrophic changes in the pyloric gland, and also of mononuclear cell infiltration. There was no correlation between the number of AM-IR cells and the degree of neutrophilic infiltration. Similar findings were also obtained for gastrin-IR cells.

CONCLUSION

AM-IR cells are present in the endocrine cells including gastrin-IR cells in the pyloric glands. These results suggest that AM may contribute to gastrin secretion in the pyloric glands.

Simulation of the daily sunlight illumination pattern for bacterial photo-hydrogen production

Methods of illumination to simulate the daily sunlight irradiation pattern were studied in relation to photohydrogen production using the photosynthetic bacterium Rhodobacter sphaeroides RV. Three illumination patterns were compared, in which the light intensity was changed in 1, 3, or 6 steps. As a control, outdoor experiments were also carried out over a 3-d period in Tsukuba, August 1996. Outdoors, hydrogen production by Rba. sphaeroides RV was dependent on the sunlight intensity: the total volume of hydrogen produced per day varied from 14 to 28 l.m(-2), while the total light energy ranged from 5.5 to 6.4 kWh.m(-2). d(-1). The maximum hydrogen production rate was 2.8 l.m(-2).h(-1) under a 4.5-cm light path and the average light energy conversion efficiency was 1.1%. Indoors, the hydrogen production rate was found to be independent of the mode of illumination among the three patterns employed. The maximum hydrogen production rate was 3.3 l.m(-2).h(-1) with a light energy conversion efficiency of 1.0%, and it was concluded that the single-step illumination method provides an appropriate simulation of sunlight. Saturation of hydrogen production occurs during high light intensity around noon and this plays a key role in the simulation.

Enhanced hydrogen production by a mutant of Rhodobacter sphaeroides having an altered light-harvesting system

A stable mutant of the photosynthetic bacterium Rhodobacter sphaeroides with an altered light-harvesting (LH) system (P3 mutant) was obtained by UV irradiation and characterized. The mutant exhibited a 2.7-fold decrease in the core antennal (LH1) content and 1.6-fold increase in peripheral antennal (LH2) content compared to the wild-type strain. The H2 evolution rates in the P3 mutant under 800- and 850-nm light, corresponding to the absorption maxima of LH2, were 1.5 times higher than in the wild-type strain. The wild-type absorption spectrum was restored in the P3 mutant when a 1.1-kb PCR-amplified fragment containing the puf promoter and pufQBA genes was ligated into a pRK-415 derivative and introduced into it. The transformant showed lower H2 production rates at 800 and 850 nm than the P3 strain carrying the control plasmid, indicating that the accelerated H2 production in the P3 mutant was a result of alterations in the LH system.

Hepatic stellate cells (Ito cells) in veno-occlusive disease of the liver after allogeneic bone marrow transplantation

AIMS

To evaluate the role of activated hepatic stellate cells (HSCs) in hepatic veno-occlusive disease (VOD) after bone marrow transcription (BMT), we studied the distribution and area of activated HSCs by immunohistochemistry for alpha-smooth muscle actin (SMA).

METHODS AND RESULTS

We examined the liver of seven autopsy cases with hepatic VOD or without VOD after allogeneic BMT and five autopsy cases without liver disease as a control both microscopically and immunohistochemically. In normal liver tissues, SMA-positive cells were observed around the central veins, while they were more frequently noted along the sinusoidal walls as well as around the central veins in liver tissues with or without VOD after BMT. The area of activated HSCs increased significantly in zones 1 and 2, and more prominently in zone 3 of the liver tissues after BMT than normal liver tissues, and was much larger in zone 3 of liver tissues with VOD. The activated HSCs were immunohistochemically negative for the regulatory contractile proteins (heavy caldesmon and calponin).

CONCLUSIONS

These results indicated that the activated HSCs may play an important role in sinusoidal fibrosis and luminal narrowing or occlusion of the central veins in VOD after BMT.

Purified fusion enzyme between rat cytochrome P4501A1 and yeast NADPH-cytochrome P450 oxidoreductase

A genetically engineered fusion enzyme between rat P4501A1 and yeast P450 reductase in the microsomal fraction of the recombinant yeast AH22/pAFCR1 was purified. The purified enzyme showed a typical CO-difference spectrum of P4501A1 and a single band with an apparent molecular weight of 125,000 on sodium dodecyl sulfate polyacrylamide gel electrophoresis. This agreed with the molecular weight of 131,202 calculated from the amino acid sequence. The purified enzyme showed both 7-ethoxycoumarin o-deethylase activity and horse heart cytochrome c reductase activity in the presence of NADPH. The 7-ethoxycoumarin o-deethylase activity depended on the species of lipid used for the reconstitution of the purified fusion enzyme although the purified enzyme showed the activity without reconstitution. The purified fusion enzyme had the Km value of 26 microM for 7-ethoxycoumarin and the maximal turnover rate of 29 mol product/min/mol enzyme at 30 degrees C.

Entrapment of Rhodobacter sphaeroides RV in cationic polymer/agar gels for hydrogen production in the presence of NH4+

Cationic polyelectrolytes (chitosan, poly-L-lysine (PLL), polyethyleneimine (PEI) and trimethylammonium glycol chitosan iodide (TGCI)) were used to entrap anoxygenic phototrophic bacteria in order to prevent the inhibitory effect of NH4+ on hydrogen production. When combined with agar gel, chitosan and PLL demonstrated no obvious repressive effect on hydrogen production by Rhodobacter sphaeroides under light-anaerobic conditions with lactate and glutamate as the carbon and nitrogen sources, respectively. On the other hand, both PEI and TGCI exerted a detrimental effect on hydrogen production under these conditions. Hydrogen production in the presence of NH4+ by the bacteria entrapped in the complex gel containing chitosan and agar improved considerably compared to that in the control containing only agar. Evidence shows that chitosan improves the hydrogen production via various effects. Diffusion tests demonstrated that the addition of chitosan increased to some extent the resistance to the diffusion of positively charged NH4+, but had no effect on negatively charged lactate. A buffer effect in the complex gels was also revealed.

Photobiological hydrogen production

The principles and recent progress in the research and development of photobiological hydrogen production are reviewed. Cyanobacteria produce hydrogen gas using nitrogenase and/or hydrogenase. Hydrogen production mediated by native hydrogenases in cyanobacteria occurs under in the dark under anaerobic conditions by degradation of intracellular glycogen. In vitro and in vivo coupling of the cyanobacterial photosynthetic system with a clostridial hydrogenase via cyanobacterial ferredoxin was demonstrated in the presence of light. Genetic transformation of Synechococcus PCC7942 with the hydrogenase gene from Clostridium pasteurianum was successful; the active enzyme was expressed in PCC7942. The strong hydrogen producers among photosynthetic bacteria were isolated and characterized. Coculture of Rhodobacter and Clostriudium was applied for hydrogen production from glucose. A mutant strain of Rhodobacter sphaeroides RV whose light-harvesting proteins were altered was obtained by UV irradiation. Hydrogen productivity by the mutant was improved when irradiated with monochromatic light of some wavelengths. The development of photobioreactors for hydrogen production is also reviewed.

In vitro and in vivo coupling of Thiocapsa hydrogenase with cyanobacterial and algal electron mediators

H2 activation by the oxygen-tolerant hydrogenase from the purple sulfur bacterium Thiocapsa roseopersicina, using electron mediators of cyanobacterial and algal origin, has been demonstrated. Ferredoxins, either from the cyanobacterium Synechococcus PCC7942 or the green alga Scenedesmus obliquus, are capable of providing electrons for hydrogenase-mediated H2 evolution. The high-potential cytochrome c6 from Synechococcus PCC7942 proved to be capable of accepting electrons derived from hydrogenase-mediated H2 oxidation. In subsequent experiments, Thiocapsa hydrogenase was introduced into the cells of Synechococcus PCC7942 by electroporation, for enhanced H2 production.

Antimicrobial flavonoids from Glycyrrhiza glabra hairy root cultures

A new compound named licoagrodione was isolated from the hairy root cultures of Glycyrrhiza glabra (Fabaceae) together with five known prenylated flavonoids. The structure of licoagrodione has been elucidated on the basis of spectral evidence and it was found to have antimicrobial activity indicated by disc diffusion method.

Adrenomedullin in the gastrointestinal tract. Distribution and gene expression in rat and augmented gastric adrenomedullin after fasting

The aim of this study was to investigate the regional distribution, molecular forms, and gene expression of adrenomedullin in the rat gastrointestinal tract and to examine physiological changes in gastric adrenomedullin after 24-h fasting. The tissue concentration was measured by radioimmunoassay. The molecular forms were analyzed by high performance liquid chromatography. mRNA levels were quantified by Northern blotting and cells positive for adrenomedullin immunoreactivity were localized by immunohistochemistry. A high concentration of adrenomedullin was found in stomach, cecum, and colon (450-520 fmol/g wet tissue). Adrenomedullin immunoreactivity was also detected in duodenum, jejunum, and ileum (200-250 fmol/g wet tissue). Transcripts of the adrenomedullin gene were widely expressed throughout the gastrointestinal tract. The major form of adrenomedullin immunoreactivity in stomach and colon corresponded precisely with authentic adrenomedullin peptide. Adrenomedullin immunoreactive cells were present in the gastrointestinal endocrine system. The concentration and mRNA level of gastric adrenomedullin after fasting were significantly increased compared with findings in controls. Adrenomedullin is ubiquitous in the gastrointestinal tract, and may be produced by endocrine cells. The results suggest that adrenomedullin, through its potent vasodilating activity, may play some role, in the stomach including the regulation of the mucosal blood flow.

The characterization of two Dictyostelium discoideum genes encoding ribosomal proteins with sequence similarity to rat L27a and L37a

Two Dictyostelium discoideum ribosomal protein genes, denoted DdL27a and DdL37a, were isolated and sequenced. The DdL27a gene contained an open reading frame of 148 amino acids coding for a putative 16,407 Da protein, which was similar to rat L27a (82.6% similarity) and to ribosomal proteins from other species. The gene contained a 311-bp intron downstream from the ATG initiation codon with an A+T content of 75%. The DdL37a gene encoded a 9,999 Da protein consisting of 91 amino acids, which had high sequence similarity to rat, human, and chicken ribosomal protein L37a, and was interrupted by two introns of 254 bp and 75 bp in length. The DdL37a protein contained a typical zinc finger motif (Cys-X2-Cys-X14-Cys-X2-Cys), which may be involved in the interaction of proteins with nucleic acids. Genomic DNA blot analysis indicated that the DdL27a and DdL37a genes are present in single copies in the Dictyostelium haploid genome. The DdL27a and DdL37a mRNA were expressed maximally in growing amoebae, and their levels decreased during multicellular development, coordinately with the observed decrease in ribosome accumulation during later development.

The role of tissue factor in the pathogenesis of thrombosis and atherosclerosis

TF is a major regulator of coagulation and hemostasis. High levels of TF antigen and activity are detected in atherosclerotic lesions, particularly in the advanced lesions. When the plaques are ruptured or eroded, exposure of cellular and extracellular TF to circulating blood play a pivotal role in mediating fibrin-rich thrombus formation leading to acute coronary syndromes. On the other hand, activation of blood coagulation and deficiency of coagulation inhibitors, without endothelial cell denudation, are considered to be an important factor of thrombogenesis in the microcirculation. The imbalance between TF and TFPI seems to be important in promoting fibrin thrombus formation in the lung of endotoxin induced DIC condition.

[High-dose steroid therapy for sudden deafness--efficacy in severe cases]

We studied the efficacy of high-dose steroid therapy for severe sudden deafness, and evaluated various factors that affect hearing recovery; i.e., severity of hearing loss, age, presence of vertigo and time to the beginning treatment. Twenty-eight patients with idiopathic sudden sensorineural hearing loss whose hearing levels were 60 dB or more were analyzed. They were given 200 mg of prednisolone per day intravenously according to Stennert's method. Hearing recovery was assessed by the criteria of the Sudden Deafness Research Group of the Japanese Ministry of Health and Welfare. The overall recovery rate and cure rate were 50% and 14%, respectively. Patients whose initial hearing levels were within 90 dB showed a significantly higher cure rate than those with above 90 dB (36% (n = 11) vs 0% (n = 17), p < 0.05). The cure rate was significantly higher in the vertigo (-)-group than in the vertigo (+)-group (40% (n = 10) vs 0% (n = 18), p < 0.02). The cure rate was also higher in patients under 50 years of age who were treated within 7 days after onset than in the others (31% (n = 13) vs 0% (n = 15), p < 0.05). The recovery rate was higher when patients were under 50 years of age (63% vs 33%), treated within 7 days after onset (56% vs 42%), or had an initial hearing level within 90 dB (55% vs 47%); however, the differences were not statistically significant. We conclude that these prognostic factors are important for predicting the hearing recovery of patients with severe sudden deafness who undergo high-dose steroid therapy and, therefore, for determining whether this therapy is indicated.