Efficacy and safety of plasma exchange in interstitial lung diseases with anti-melanoma differentiation-associated 5 gene antibody positive clinically amyopathic dermatomyositis.

OBJECTIVE: Clinically amyopathic dermatomyositis (CADM) patients frequently develop refractory interstitial lung disease (ILD), with a poor prognosis. We aimed to verify the efficacy and safety of plasma exchange (PE) treatment for ILD in CADM. METHOD: A retrospective case-control study was conducted to compare clinical outcomes with and without PE treatment in CADM-ILD patients refractory to combination therapy of high-dose glucocorticoids, calcineurin inhibitors, and cyclophosphamide. Among 19 enrolled patients, 11 were further treated with PE. We compared survival rates and other clinical characteristics. PE consisted of either fresh-frozen plasma or albumin as a replacement solution. RESULTS: Basal clinical characteristics at diagnosis, including age, gender, serum ferritin, Krebs von den Lungen-6 (KL-6), C-reactive protein, and respiratory function tests, did not differ between the two groups. The survival rate for treatment with PE was higher than for treatment without PE (91% and 50%, respectively, p < 0.05). Among PE-treated patients, anti-melanoma differentiation-associated gene-5 (anti-MDA-5) antibody titre, ferritin, and KL-6 as serological activity markers were sustainably reduced only after initiating PE. Therapeutic intervention with PE reduced the frequency of exacerbation of ILD requiring methylprednisolone pulse therapy. The occurrence of bacterial, fungal, and cytomegalovirus infection did not differ between the groups with and without PE, and adverse events associated with PE resolved with appropriate intervention. CONCLUSION: Combination therapy with PE was associated with an improved survival rate, and may be effective for the management of refractory ILD in CADM patients. A personalized therapeutic strategy including PE could be introduced for fatal rapidly progressive ILD.

Significance of soil moisture on temperature dependence of Hg emission.

Soil moisture is a key factor for mercury (Hg) emission from soil. Despite its significance for Hg emissions, the effect of soil moisture on Hg flux and fractions has not been thoroughly investigated. The objective of this study was to elucidate the influences of soil moisture and temperature on Hg fluxes from soils and Hg fractions. A kinetic study was performed to measure Hg emission fluxes of six soil samples under different temperature (T) (15 °C, 20 °C, 25 °C, 30 °C, and 35 °C) and moisture conditions (0%, 10%, and 20% added water). The results showed that the Hg fluxes increased with increases in T and soil moisture. A linear correlation was found between ln (Hg emission flux) and 1/T for the six soil samples at different moisture contents (R2 = 0.73-0.99). The range of activation energy (Ea) values was 25.31-57.86 kJ/mol. The Hg fractions in soils of different moisture content were determined by a sequential extraction method. The results demonstrated that soil moisture affected the Hg fractions in soils. The Ea values had different relationships with soil moisture in different soils. There were correlations between Ea and the elemental and mercuric sulfide fractions for air-dried soils. However, for moist soils, Ea was negatively correlated with the water-soluble and acid-soluble fractions. Collectively, the combination of the Hg emission kinetics and Hg fraction measurement of different moist soils indicated that Hg emission was affected by both total Hg concentration and Hg fractions.

The herpes simplex virus-1 Us3 protein kinase blocks CD8T cell lysis by preventing the cleavage of Bid by granzyme B.

The Us3 kinase is part of the antiapoptotic arsenal that salvages herpes simplex virus (HSV)-1-infected cells from damage caused by different stimuli. We demonstrate that Us3 protects HSV-1-infected cells from lysis by MHC class I-restricted CD8T cells without affecting antigen presentation. Expression of Us3 was associated with inhibition of caspase activation and reduced cleavage of the proapoptotic protein Bid. Recombinant granzyme B (GrB) failed to cleave Bid in cytosolic extracts from Us3 positive cells, while recombinant Bid served as substrate for Us3 phosphorylation, suggesting that modification of Bid by Us3 blocks its processing by GrB. Our data illustrate a new strategy of viral escape, where modification of a cellular proapoptotic substrate may prevent lysis of the infected cells without affecting other T-cell functions.

Mid-term outcome after partial left ventriculectomy in pediatric patients.

From May 1998 to April 2000, we performed partial left ventriculectomy (PLV) in 3 pediatric patients with dilated cardiomyopathy (DCM). At the time of the surgery, their age ranged from eight months to three years. The first patient eventually had to receive a heart transplant, but all patients treated with PLV are alive to this day. Patient #1 was diagnosed with DCM at the age of five months, PLV was done on a semi-urgent basis at the age of eight months, when medium dose IV catecholamine therapy and mechanical ventilation were required. Fraction shortening (FS) as shown by echocardiography increased postoperatively from 8% to 15% along with marked clinical improvement. Her heart failure deteriorated three months after the surgery, and received a heart transplant in the United States when she was one year and two months old. Patient #2 developed severe heart failure two months after correction of a ventricular septal defect. Aggressive medical therapy failed to improve his condition, therefore PLV was done on an elective basis at the age of three years and five months. [The patient was initially hospitalized and underwent low dose catecholamine.] Postoperative course was well. The ventriculography one year after surgery showed an improvement of the left ventricular FS from 12% to 27% after PLV. He was still doing well at his most recent check up. Patient #3 was diagnosed with DCM as a neonate. PLV was done on an elective basis at the age of two years and five months. Her postoperative course was generally well. FS on echocardiography increased postoperatively from 10% to 25% along with marked clinical improvement. The timing of performing PLV is the most essential factor for postoperative course in our experiences. We consider that the best timing is when aggressive catecholamine infusion or mechanical ventilation is required. The mid-term outcome of PLV of pediatric patients is considered to be acceptable. We believe that PLV should be considered as a viable option for severe DCM patients.

Hydrodynamics of cryogelation.

Cryogel, prevalent in the plasma of rheumatoid arthritis patients, is a plasma fibronectin (pFN)-extra domain A containing FN [EDA(+)FN]-fibrinogen (Fbg) aggregate formed by the addition of heparin (Hep) at low temperature. Although EDA(+)FN is not usually present in normal plasma, its prevalence in rheumatic patients induces cryogelation. In this study, we determined the hydrodynamic radius (R(h)) ratio (R(h)/R(h30)) of the cryogel component by dynamic light scattering in vitro. R(h)/R(h30) was normalized to R(h) at 30 degrees C (R(h30)) at several temperatures. The R(h)/R(h30) of Fbg was found to increase only by self-aggregation, whereas the R(h)/R(h30) of FNs does not increase in response to temperature changes. The R(h)/R(h30) of the Fbg/FN aggregate is increased by the addition of Hep, and the R(h)/R(h30) (12.5) of the Hep-induced EDA(+)FN/Fbg aggregate is greater than that (2.5) of the pFN/Fbg aggregate. These results suggest that cryogelation requires Fbg self-aggregation and the interaction between EDA(+)FN and Hep.

Inhibition of in vitro metabolism of simvastatin by itraconazole in humans and prediction of in vivo drug-drug interactions.

PURPOSE: To evaluate an interaction between simvastatin and itraconazole in in vitro studies and to attempt a quantitative prediction of in vivo interaction in humans. METHODS: The inhibitory effect of itraconazole on simvastatin metabolism was evaluated using human liver microsomes and the Ki values were calculated for the unbound drug in the reaction mixture. A physiologically-based pharmacokinetic model was used to predict the maximum in vivo drug-drug interaction. RESULTS: Itraconazole competitively inhibited the metabolism of simvastatin to M-1 and M-2 with Ki values in the nM range. The area under the curve (AUC) of simvastatin after concomitant dosing with itraconazole was predicted to increase ca. 84-101-fold compared with that without administration of itraconazole. Taking into consideration the fact that this method predicts the maximum interaction, this agrees well with the clinical observation of a 19-fold increase. A similar prediction, based on the Ki value without taking into account the drug adsorption to microsomes, led to an underevaluation of the interaction. CONCLUSIONS: It was demonstrated that the competitive inhibition of CYP3A4-mediated simvastatin metabolism by itraconazole is the main cause of the drug interaction and that a Ki value corrected for drug adsorption to microsomes is the key factor in quantitatively predicting the maximum in vivo drug interactions.

Development of a novel polycationic adsorbent for cryogel removal.

Cryogel, prevalent in the plasma of rheumatism patients, is a plasma fibronectin (pFN)-extra domain A containing FN (EDA(+)FN)-fibrinogen (Fbg) complex formed by adding heparin (HP) at a low temperature (4 degrees C). Although EDA(+)FN does not usually exist in normal plasma, its prevalence in rheumatic patients causes cryogelation in plasma. Removal of cryogel is thus a promising and novel approach to treating rheumatism. As HP-EDA(+)FN aggregate, which is induced by the main component of cryogel, is considered to be an anion, cationic materials capable of eliminating this anionic conjugate were innovated in this study. We found that an amino group density of 100-130 micromol/g (dry weight) of adsorbents prompted selective adsorption of the EDA(+)FN-HP complex. Elimination of EDA(+)FN as high as 80% accompanied by removal of the components of total FN (pFN) (10%) and Fbg (10%) in the model patient plasma was established.

Drug interaction between simvastatin and itraconazole in male and female rats.

Taking into account the species and sex differences in drug interactions based on the inhibition of cytochrome P450 (P450)-mediated drug metabolism, we examined whether the interaction between simvastatin and itraconazole observed in humans could also occur in rats, the most commonly used animal species for pharmacokinetic studies. Itraconazole inhibited the in vitro metabolism of simvastatin in female rat liver microsomes, but not in male rat liver microsomes. Using anti-P450 antisera, the main P450 isozyme responsible for the metabolism of simvastatin was identified as CYP3A in female rats and CYP2C11 in male rats. Therefore, the sex difference in the inhibition of simvastatin metabolism by itraconazole seems to be caused by a difference in the P450 isozymes responsible for the metabolism of simvastatin in male and female rats and the different ability of itraconazole to inhibit CYP3A and CYP2C11. In addition, the effect of itraconazole on the pharmacokinetics of simvastatin in rats was also investigated. The area under the curve value of simvastatin was increased approximately 1.6-fold by the concomitant use of itraconazole (50 mg/kg) in female rats, whereas in male rats, itraconazole had no effect. In conclusion, it was found that the results obtained in male rats did not reflect the results in humans as far as the inhibition of simvastatin metabolism by itraconazole was concerned. The P450 isozymes involved in the metabolism of drugs should be taken into consideration when rats are used as a model animal for humans in the investigation of drug interactions.

Preparation of gellan sulfate as an artificial ligand for removal of extra domain A containing fibronectin.

The extra domain A containing fibronectin (EDA(+)FN) concentration in plasma of rheumatoid arthritis (RA) is abnormally higher than the normal level. We synthesized various gellan-sulfate (GS) candidates as artificial ligands for removing EDA(+)FN from plasma. The interaction between these artificial ligands and EDA(+)FN was evaluated using affinity constants (KA), which were determined by surface plasmon resonance measurement. The KA (3.6 x 10(8) per M) of GS-25 [degree of substitution for sulfonation (DS) = 25%] with EDA(+)FN was higher than those of other molecules: GS-16 (DS=16%) at 8.3 x 10(7) per M, and GS-35 (DS = 35%) at 1.7 x 10(8) per M. Furthermore, GSs displayed selectivity of EDA(+)FN for binding with plasma FN (KAEDA(+)FN)/KA(plasma FN)>2). The removal ratio in plasma was measured by using GS-immobilized gel. Removals of 66, 11, 7.7, 6.2, 6.9, and 12% for EDA(+)FN, plasma FN, fibrinogen, albumin, immunoglobulin G (IgG) and antithrombin III from the patient-model plasma were, respectively, achieved with GS-25-immobilized gel. These results suggest that GS may be used as a selective artificial ligand for EDA(+)FN removal from plasma in RA treatment.

A comparison of the effects of 3-hydroxy-3-methylglutaryl-coenzyme a (HMG-CoA) reductase inhibitors on the CYP3A4-dependent oxidation of mexazolam in vitro.

HMG-CoA reductase inhibitors can be divided into two groups: those administered as the prodrug, i.e., the lactone form (e.g., simvastatin and lovastatin), and those administered in the active form, i.e., the acid form (e.g., pravastatin, fluvastatin, atorvastatin, and cerivastatin). In this study, the influence of the lactone and acid forms of various HMG-CoA reductase inhibitors on metabolism by CYP3A4, a major cytochrome P450 isoform in human liver, was investigated by determining the in vitro inhibition constant (K(i) value) using an antianxiety agent, mexazolam, as a probe substrate. In human liver microsomes, all the lactone forms tested inhibited the oxidative metabolism of mexazolam more strongly than did the acid forms, which have lower partition coefficient (logD(7.0)) values. In addition, the degree of inhibition of mexazolam metabolism tended to increase with an increasing logD(7.0) value of the HMG-CoA reductase inhibitors among the lactone and acid forms. In particular, pravastatin (acid form), which has the lowest logD(7.0) value, failed to inhibit CYP3A4 activity. Taking account of the lipophilicity of the inhibitors, in conjunction with the CYP3A4-inhibitory activity, could be very useful in predicting drug interactions between substrates of CYP3A4 and HMG-CoA reductase inhibitors.

Cryogelation in vitro.

Cryogel is a physical gel formed by the heterophilic aggregation of extra domain A containing fibronectin (EDA(+)FN), plasma fibronectin (pFN), fibrinogen (Fbg) and heparin (Hep). Cryogelation is controlled by the interactions between each aggregate and the amount of aggregates. Therefore, the present study attempted to elucidate these properties by studying turbidity (tau). Although only Fbg formed a self-aggregate under low temperatures, from the temperature dependence of tau, the amount of aggregate in three-element (pFN/Fbg/Hep) solution surpassed that of the EDA(+)FN/Fbg/Hep system. The optimal condition for cryogelation was afforded by a solution with Fbg/EDA(+)FN/pFN/Hep expressed in the molar ratio of 12:0.04:0.79:1. This cryogel structure in solution was probably formed via structural changes induced by pFN in Fbg. The structural change in Fbg was examined by circular dichroism under optimal conditions. This concept was based on observations of the direct transmission scanning electron microscopy of a cryogel. The EDA(+)FN/pFN/Fbg/Hep aggregates displayed a network structure that manifested particulate crosslinkage. Cryogelation, a phenomenon related to induction of rheumatoid arthritis in humans, was facilitated by both the EDA(+)FN-Hep interaction and the structural changes of Fbg induced by pFN.

A new distinctive species of pagurid hermit crab (Crustacea: Decapoda: Anomura) from Japan.

A new species of pagurid hermit crab, Pagurus decimbranchiae, is described and illustrated based on 20 specimens collected from shallow waters of the Pacific coast of Japan ranging from Boso Peninsula to Tanegashima Island. It is quite distinctive in having the rudimentary arthrobranch on the third maxilliped represented by a single bud, however close morphological similarity is found between the new species and P. moluccensis Haig and Ball. Comparisons are also made among other species, including P. boriaustraliensis Morgan, P. sp. cf. boriaustraliensis sensu Rahayu and Komai (2000) and the members of the P. anachoretus group. The present generic assignment of the new species should be considered provisional, as more extensive study is needed to investigate phylogenetic relationships of the new species and the other species of Pagurus.

Investigation into the mode of action of R-91650, an arylpiperazinyl fluoroquinolone, on feline immunodeficiency virus replication inhibitory activity.

The mode of action of R-91650, an arylpiperazinyl fluoroquinolone, on feline immunodeficiency virus (FIV) replication inhibitory activity was investigated. R-91650 inhibited replication of FIV at non-cytotoxic concentration levels in both acutely infected peripheral blood mononuclear cells and chronically infected P-CrFK cells. The compound reduced the intracellular p24 concentration levels in P-CrFK cells in a dose-dependent manner. Northern blot analysis revealed that R-91650 selectively prevented the accumulation of FIV mRNA in P-CrFK cells. However, the compound did not inhibit FIV-long terminal repeat (LTR) promoter activity in the reporter gene expression analysis. These data suggest that R-91650 is a novel inhibitor of FIV replication that inhibits a certain step or steps following transcription initiation of the FIV-LTR promoter.