NMR analysis of 15N-labeled naphthyridine carbamate dimer (NCD) to contiguous CGG/CGG units in DNA

The structure of the complex formed by naphthyridine carbamate dimer (NCD) binding to CGG repeat sequences in DNA, associated with fragile X syndrome, has been elucidated using 15N-labeled NCD and 1H-15N HSQC. In a fully saturated state, two NCD molecules consistently bind to each CGG/CGG unit, maintaining a 1 : 2 binding stoichiometry.

Alterations in the chondroitin sulfate chain in human osteoarthritic cartilage of the knee

OBJECTIVE

To determine whether the structure of chondroitin sulfate (CS) in cartilage is reflected by the degree of cartilage degeneration in patients with osteoarthritis (OA) of the knee and to determine how CS biosynthesis affects cartilage degeneration.

DESIGN

Two osteoarthritic cartilage samples were obtained from medial femoral condyle (MFC) and lateral femoral condyle (LFC) of 24 knees with end-stage OA. The samples were assigned to two groups as follows: lesion and remote cartilage were adjacent to and remote from the osteoarthritic cartilage, respectively. Histological grade was determined according to the Mankin score. The CS concentration and chain length were determined using high-performance liquid chromatography (HPLC) and gel filtration chromatography, respectively. Expression of the gene encoding CS glycosyltransferase was evaluated using a real-time quantitative polymerase chain reaction (qPCR) assay. These results were compared between lesion and remote cartilage.

RESULTS

The Mankin score indicated that lesion cartilage was more degraded compared with remote cartilage. Although the CS levels varied among individuals, the mean CS concentration and chain length were significantly lower and shorter in lesion cartilage than in remote cartilage, respectively (concentration: 12.04 vs 14.84 μg/mg wet weight, P = 0.021; chain length: 5.36 vs 6.19 kDa, P = 0.026). Three genes encoding CS glycosyltransferases (CHPF, CSGALNACT1, CSGALNACT2) were expressed at lower levels in lesion cartilage.

CONCLUSIONS

In the osteoarthritic knee, the CS concentration and chain length were reduced closer to the more degraded cartilage with decreasing CS glycosyltransferase gene expression. Inhibition of CS glycosyltransferase gene expression may reduce CS chain length, which may contribute to OA progression.

Enhanced removal of chemical oxygen demand, nitrogen and phosphorus using the ameliorative anoxic/anaerobic/oxic process and micro-electrolysis

Synthetic wastewater was treated using a novel system integrating the reversed anoxic/anaerobic/oxic (RAAO) process, a micro-electrolysis (ME) bed and complex biological media. The system showed superior chemical oxygen demand (COD), total nitrogen (TN) and total phosphorus (TP) removal rates. Performance of the system was optimised by considering the influences of three major controlling factors, namely, hydraulic retention time (HRT), organic loading rate (OLR) and mixed liquor recirculation (MLR). TP removal efficiencies were 69, 87, 87 and 83% under the HRTs of 4, 8, 12 and 16 h. In contrast, HRT had negligible effects on the COD and TN removal efficiencies. COD, TN and TP removal efficiencies from synthetic wastewater were 95, 63 and 87%, respectively, at an OLR of 1.9 g/(L·d). The concentrations of COD, TN and TP in the effluent were less than 50, 15 and 1 mg/L, respectively, at the controlled MLR range of 75-100%. In this system, organics, TN and TP were primarily removed from anoxic tank regardless of the operational conditions.

Quantification of hepatitis C virus in patients treated with peginterferon-alfa 2a plus ribavirin treatment by COBAS TaqMan HCV test

Extremely low levels of serum hepatitis C virus (HCV) RNA can be detected by COBAS TaqMan HCV test. To investigate whether the COBAS TaqMan HCV test is useful for measuring rapid virological response (RVR) and early virological response (EVR) to predict sustained virological response (SVR), we compared the virological response to PEG-IFN-alfa 2a plus RBV in 76 patients infected with HCV genotype 1 when undetectable HCV RNA by the COBAS TaqMan HCV test was used, with those when below 1.7 log IU/mL HCV RNA by COBAS TaqMan HCV test was used, which corresponded to the use of traditional methods. Among the 76 patients, 28 (36.8%) had SVR, 13 (17.1%) relapsed, 19 (25.0%) did not respond, and 16 (21.0%) discontinued the treatment due to side effects. The positive predictive values for SVR based on undetectable HCV RNA by COBAS TaqMan HCV test at 24 weeks after the end of treatment [10/10 (100%) at week 4, 21/23 (91.3%) at week 8 and 26/33 (78.7%) at week 12] were superior to those based on <1.7 log IU/mL HCV RNA [17/19 (89.4%) at week 4, 27/38 (71.0%) at week 8, and 27/43 (62.7%) at week 12]. The negative predictive values for SVR based on <1.7 log IU/mL HCV RNA by COBAS TaqMan HCV test [46/57 (80.7%) at week 4, 37/38 (97.3%) at week 8, and 32/33 (96.9%) at week 12] were superior to those based on undetectable HCV RNA [48/66 (72.7%) at week 4, 46/53 (86.7%) at week 8, and 41/43 (95.3%) at week 12]. The utilization of both undetectable RNA and <1.7 log IU/mL HCV RNA by COBAS TaqMan HCV test is useful and could predict SVR and non-SVR patients with greater accuracy.

Effects of variations of extracellular polymeric substances and soluble microbial products on activated sludge properties during anaerobic storage

Anaerobic storage always takes place in wastewater treatment plants or sludge handling processes. Although extracellular polymeric substances (EPS) and soluble microbial products (SMP) are well known to be the two important chemical parameters to influence sludge properties, few studies have demonstrated the coexisting effects of the two biopolymers on sludge characteristics during anaerobic storage of activated sludge. The experiments, conducted with acetate as the substrate at 35 degrees C and 25 degrees C and with glucose at 35 degrees C, indicated that EPS content decreased significantly in the first two or three days and later slightly increased in all runs, while SMP concentration varied gradually from 66-105mg l(-1) to 330-420mg 1(-1), increasing almost linearly with anaerobic storage time. All the components in EPS decreased after anaerobic storage, especially protein, which was the dominant organic compound in both EPS and SMP with more than 60% of the total amounts of the two biopolymers. Protein and DNA in SMP increased to a large extent and mainly contributed to the three-to five- fold increase in the total amount of SMP, while carbohydrates in SMP remained at a relatively low level. From statistical analysis, some major correlations could be obtained: a weak correlation existed between SMP and EPS; SMP were much more significantly correlated than EPS with sludge properties (biomass, specific resistance to filtration, sludge volume index and relative hydrophobicity of sludge surface). The results indicated that SMP, not EPS, significantly influence the sludge dewatering and settling properties, being deteriorated by more SMP production from cell lysis during anaerobic storage.

Effects of nutrient addition on phenol biodegradation rate in biofilm reactors for hypersaline wastewater treatment

Hypersaline wastewater, generated by many industrial activities, is difficult to treat through conventional biological processes. In this kind of hypersaline environment, complex nutrients are needed for the normal growth of many microorganisms. For this paper, the organisms were taken from a municipal wastewater treatment plant and acclimated to 15% salinity in a biofilm treatment process (Sequencing Batch Biofilm Reactor) during the treatment of phenol-containing synthetic wastewater. They are used to evaluate the effects of nutrient addition on the phenol biodegradation rate. Adding yeast extract, glucose, KCl and four mineral nutrients into the shaking flasks containing wastewater and cultivating organisms, revealed phosphate as the crucial nutrient stimulating phenol biodegradation at 15% salinity. The operation results of the sequencing batch biofilm reactor indicates that phosphate content increased up to five times the original level can increase the phenol removal rate by 150%. A 99% phenol removal efficiency could be achieved by shortening the reaction time in the biofilm reactor from 40 h to 16 h, compared with basic nutrients added. In this article we applied an applicable and effective shaking-culture method to determine nutrient requirements in biotreatment processes without stopping the running reactors.

A novel control process of cyanobacterial bloom using cyanobacteriolytic bacteria immobilized in floating biodegradable plastic carriers

A process using a floating carrier for immobilization of cyanobacteriolytic bacteria, B.cereus N-14, was proposed to realize an effective in situ control of natural floating cyanobacterial blooms. The critical concentrations of the cyanobacteriolytic substance and B.cereus N-14 cells required to exhibit cyanobacteriolytic activity were investigated. The results indicated the necessity of cell growth to produce sufficiently high amounts of the cyanobacteriolytic substance to exhibit its activity and also for conditions enabling good contact between high concentrations of the cyanobacteriolytic substance and cyanobacteria. Floating biodegradable plastics made of starch were applied as a carrier material to maintain close contact between the immobilized cyanobacteriolytic bacteria and floating cyanobacteria. The floating starch-carriers could eliminate 99% of floating cyanobacteria in 4 d. Since B.cereus N-14 could produce the cyanobacteriolytic substance under the presence of starch and some amino acids, the cyanobacteriolytic activity could be attributed to carbon source fed from starch carrier and amino acids eluted from lysed cyanobacteria. Therefore, the effect of using a floating starch-carrier was confirmed from both view points as a carrier for immobilization and a nutrient source to stimulate cyanobacteriolytic activity. The new concept to apply a floating carrier immobilizing useful microorganisms for intensive treatment of a nuisance floating target was demonstrated.

Biodegradation of microcystis and microcystins by indigenous nanoflagellates on biofilm in a practical treatment facility

The potential for degradation of Microcystis and microcystins by organisms in biofilm in a practical biological treatment facility combined with conventional treatment processes was examined. Viable cells of Microcystis viridis, which produced microcystin LR, RR and YR, were degraded in 6 to 10 days by the addition of biofilm collected in early summer, mid-summer and autumn. Monas sp. grew remarkably well compared with other organisms in the samples of all seasons. Therefore, we conclude that Monas sp. was indigenous animals in the biological treatment facility and was able to degrade Microcystis cells. Some previous studies reported the predation of Microcystis cells by Monas guttula in pure culture conditions (monoxenic culture). We clarified that Monas sp. can grow and prey on Microcystis cells even in mixed culture including many kinds of other organisms in biofilm in a practical treatment facility. Also, intracellular microcystin LR, RR and YR in Microcystis cells could be degraded simultaneously with high reduction of Microcystis cells by organisms in biofilm.

New in-vivo calibration phantoms and their performance

New in-vivo calibration phantoms (anthropometric phantoms) were developed to meet the needs for Japanese standard phantoms. Two important characteristics of these phantoms were that (1) they were designed using Japanese body size survey data, and (2) they were designed so that they can be adapted to various positions or geometries. The performance of these phantoms was tested with respect to body size, activity distribution along the axis, and counting efficiency. The actual dimensions of the anthropometric phantoms were compared with the survey data. Most items (31 of 47) indicated good agreement between the actual values and the survey data for the adult anthropometric phantom. The activity distribution for the anthropometric phantoms was compared with that for block phantoms that simulate a uniform activity distribution. The anthropometric phantoms have some gaps in their joints. The measurement results, however, indicated that these gaps did not significantly affect the overall accuracy of the measurements. Differences in counting efficiency between the block phantoms and the anthropometric phantoms for the same age were no more than 6%.

Characterization of an algae-lytic substance secreted by Bacillus cereus, an indigenous bacterial isolate from Lake Kasumigaura

In order to develop a practical biological strategy for water bloom-control in Lake Kasumigaura, indigenous algae-lytic bacteria targeting Microcystis spp. (the dominant cyanobacteria), was first carried out. Some basic lytic characteristics of the isolates concerning the biological and physico-chemical factors in actual water environments were then investigated. Fifteen algae-lytic bacteria were successfully isolated using the double layer method. The isolate showing the highest lytic activity was identified as Bacillus cereus based on the 16SrRNA sequence. Extracellular products of B. cereus were found to be responsible for algae-lytic activity. Algae-lytic assay tests using bacterial supernatants pre-treated under several conditions indicated that the majority of the effective algae-lytic substances were either hydrophilis or hydrophobics with a carbon number less than 18, and with molecular weight less than 2000 Da. The algae-lytic activity of the bacterial supernatant was found to be enhanced under alkaline conditions, but it was lost under acidic conditions. This pH specific characteristic is advantageous for application in water bloom environments where the pH is usually in the alkaline region.

Degradation of microcystin by biofilm in practical treatment facility

Potential for degradation of microcystin by biofilm was examined by some batch experiments using biofilm scraped from practical biological treatment facility combined with conventional treatment processes. The viable cells of Microcystis viridis, which produced microcystin LR, RR and YR were degraded at 6 to 10 days by the addition of biofilm. Biofilm collected in summer season had especially higher potential for degradation of Microcystis with complete degradation at 6 days. In all seasons, Monas spp. grew remarkably, accompanied with the higher decrease of the viable cells of Microcystis and the micro-animals were considered as a main predator for Microcystis cells. Intracellular microcystin LR, RR, YR were degraded simultaneously with high reduction of Microcystis cells. Dissolved microcystin LR of 1,000 microg l(-1) was effectively degraded by indigenous aquatic bacteria on biofilm during 5 days, the degradability became higher with the increase in the concentration of microcystin LR. From the results of our research, it was clarified that the aggregated microorganisms consisting of biofilm had high potential for degradation of intracellular and dissolved microcystin.

Use of artificial neural network in the prediction of algal blooms

A model to quantify the interactions between abiotic factors and algal genera in Lake Kasumigaura, Japan was developed using artificial neural network technology. Results showed that the timing and magnitude of algal blooms of Microcystis, Phormidium and Synedra in Lake Kasumigaura could be successfully predicted. As for the newly occurring dominant Oscillatoria, results were not satisfactory. The evaluation of the importance of factors showed that Microcystis, Phormidium, Oscillatoria and Synedra were alkalophilic. The algal proliferation for Microcystis, Oscillatoria and Synedra decrease due to the increase in total nitrogen, while the growth of Phormidium is enhanced with more nitrogen. In addition, the algal density is affected by zooplankton grazing but with the exception of Phormidium due to it being poor food source. Algal responses to the orthogonal combinations of the external environmental factors, chemical oxygen demand, pH, total nitrogen and total phosphorus at three levels were modeled. Various combinations of environmental factors enhance the proliferation of some algae while other combinations inhibit bloom formation.

Discovery of a non-peptide small molecule that selectively mimics the biological actions of calcitonin

Calcitonin (CT), a 32-amino acid peptide hormone secreted mainly from the thyroid gland, plays an important role in maintaining bone homeostasis. To discover non-peptide small molecules with biological actions similar to those of CT, a cell-based screening of an in-house chemical library was performed and a pyridone derivative (SUN B8155) was identified. Like CT, it elevated cyclic AMP (cAMP) levels in T47D and UMR106-06 cells which endogenously express human and rat CT receptor, respectively. SUN B8155 also stimulated cAMP formation in cells expressing recombinant human CT receptor, but not in those expressing human parathyroid hormone/parathyroid hormone-related peptide receptor. Accumulation of cAMP in T47D cells was blocked by a selective antagonist of CT receptor, salmon CT(8-32), whereas SUN B8155 did not displace the specific binding of [(125)I]CT to the receptor. Our results suggested that the compound selectively interacts with the CT receptor by a mechanism similar to but probably different from that of CT itself. In rats, intraperitoneal administration of SUN B8155 significantly lowered serum calcium levels, like CT. Our results demonstrate, for the first time, that the biological activities of the newly identified small molecule can mimic that of CT, acting via the CT receptor.

Development status of Terumo implantable left ventricular assist system

We have been developing an implantable left ventricular assist system (T-ILVAS) featuring a magnetically suspended centrifugal pump (MSCP) since 1995. In vitro and in vivo studies using a prototype MSCP composed of a polycarbonate housing and impeller (196 ml) have demonstrated long-term durability and excellent blood compatibility for up to 864 days, and excellent stability of the magnetic bearing of the MSCP. These preliminary results strongly suggested that the magnetic bearing of the MSCP is reliable and is a most feasible mechanism for a long-term circulatory assist device. We have recently devised a clinical version pump made of titanium (180 ml) with a new position sensor mechanism and a wearable controller with batteries. Cadaver fit study confirmed that the Type IV pump could be implanted in a small patient with a body surface area as small as 1.3. The in vitro performance tests of the Type IV pump demonstrated excellent hydrodynamic performances with an acceptable hemolysis rate. New position sensors for the titanium housing showed more uniform sensor outputs of a magnetic bearing than in the prototype polycarbonate pump. The Type IV pump then was evaluated in vivo in 6 sheep at the Oxford Heart Centre. Four sheep were electively sacrificed at 3 months and were allowed to survive for more than 6 months for long-term evaluation. In this particular series of experiments, no anticoagulant/antiplatelet regimen was utilized except for a bolus dose of heparin during surgery. There was a left ventricular mural thrombi around the inflow cannula in 1 sheep. Otherwise, there was no mechanical failure nor sign of thromboembolism throughout the study.

N-methyl-D-aspartate receptors regulate a group of transiently expressed genes in the developing brain

Mammalian brain development requires the transmission of electrical signals between neurons via the N-methyl-d-aspartate (NMDA) class of glutamate receptors. However, little is known about how NMDA receptors carry out this role. Here we report the first genes shown to be regulated by physiological levels of NMDA receptor function in developing neurons in vivo: NMDA receptor-regulated gene 1 (NARG1), NARG2, and NARG3. These genes share several striking regulatory features. All three are expressed at high levels in the neonatal brain in regions of neuronal proliferation and migration, are dramatically down-regulated during early postnatal development, and are down-regulated by NMDA receptor function. NARG2 and NARG3 appear to be novel, while NARG1 is the mammalian homologue of a yeast N-terminal acetyltransferase that regulates entry into the G(o) phase of the cell cycle. The results suggest that highly specific NMDA receptor-dependent regulation of gene expression plays an important role in the transition from proliferation of neuronal precursors to differentiation of neurons.

Seasonal variation in frequency of dividing cells of freshwater phytoplankters

The frequency of dividing cells (FDC) of a natural phytoplankton community was studied seasonally in a freshwater pond to which water directly from Lake Kasumigaura was supplied. Phytoplankton samples were collected every 3 h at three depths (5, 30 and 75 cm) over 24 h periods in each of the four seasons and examined for FDC, cell size and abundance. Dominant phytoplankton species were Synedra ulna, Cyclotella kutzingiana, Chlamydomonas cingulata and Oscillatoria tenuis with Melosira italica, Cryptomonas ovata, and Synechococcus sp. being seasonally abundant. All species showed a similar FDC pattern related to the light-dark period that is a moderately phased division with the maximum FDC between 21:00-03:00.

Measurements of summer radon and its progeny concentrations along with environmental gamma dose rates in Taiwan

The concentrations of 222Rn (radon) and its progeny with surrounding environmental gamma-dose rates were measured simultaneously inside and outside of buildings at 10 locations around Taipei and Hualien in Taiwan. For summer radon in Taiwan, indoor concentrations were estimated to be about 20 Bq m(-3) with about 90 nSv h- of environmental gamma, and outdoors, about 10 Bq m(-3) with about 70 nSv h(-1). The equilibrium factors were calculated to be 0.2-0.3 indoors and 0.3-0.4 outdoors. Indoor radon concentration had a weak positive correlation with gamma-dose rate. Since there is a possibility that high radon concentrations exist indoors during the cool season in Taiwan because of extremely low ventilation rates in the dwellings, a winter survey in January through February will be needed for future estimation of the annual effective dose.

Long-term evaluation of extracorporeal shock-wave lithotripsy for cholesterol gallstones

BACKGROUND

Extracorporeal shock-wave lithotripsy (ESWL) is a treatment that preserves the gallbladder. Problems after ESWL treatment include stone recurrence and the development of biliary symptoms.

METHODS

Two hundred and sixty-two patients with cholesterol-type gallstones, the best indication for ESWL treatment, and 42 control patients with cholesterol-type gallstones who received no treatment entered this study. We evaluated the factors associated with recurrence of gallstones after stone clearance and the development of biliary symptoms after ESWL treatment.

RESULTS

The 3-, 5- and 7-year cumulative probabilities of gallstone recurrence were 20.6, 27.1 and 33.1%, respectively, with the recurrence probability significantly lower in patients with good gallbladder contractility. In patients with recurrence, ursodeoxycholic acid (UDCA) treatment was effective. In 69 patients with residual gallstones, the 3-, 5- and 7-year cumulative risks of biliary symptoms were 17.3, 24.9 and 30.5%, respectively. With residual gallstones, the risk of biliary symptoms developing was significantly lower in patients with a < or = 3 mm fragment size at the end of ESWL treatment and in those treated consistently with UDCA for 6 months or more after treatment with ESWL. The risk of biliary symptoms was significantly lower in ESWL-treated patients with residual stones who had a < or = 3 mm fragment size after treatment compared to those of control patients.

CONCLUSIONS

Ursodeoxycholic acid was effective in clearing stones in patients with gallstone recurrence. In patients with residual stones, the fragmentation of stones to < or = 3 mm and UDCA administration effectively reduced the risk of subsequent biliary symptoms.

Clinical evaluation of sonoelasticity measurement in liver using ultrasonic imaging of internal forced low-frequency vibration

The aim of this study is to evaluate liver elasticity noninvasively. We have already proposed an ultrasonic imaging system that can reconstruct vibration maps inside tissue under forced mechanical vibration. With this system, shear elastic properties of soft tissue can be evaluated as vibration velocities. Theoretically, these velocities increase with the increase of tissue elasticity. Sonoelasticity imaging was performed on 236 patients with chronic hepatitis and liver cirrhosis, and 50 healthy volunteers. The average of the velocities was 598.8 +/- 151.7 cm/s in healthy volunteers, 984.4 +/- 362.5 cm/s in chronic hepatitis and 1189.0 +/- 411.7 cm/s in liver cirrhosis. The average velocity of Child C group was statistically faster than those of Child A and B groups. Fibrotic rate from biopsy specimens statistically had the strongest positive correlation with velocities. With our system, the degree of liver fibrosis and function can be estimated objectively and noninvasively.

Crystallization and preliminary X-ray analysis of chondroitin sulfate ABC lyases I and II from Proteus vulgaris

Chondroitin sulfate ABC lyases (E.C. 4.2.2.4) are broad-specificity glycosaminoglycan-degrading enzymes. Their preferred substrates are chondroitin sulfate and dermatan sulfate, which are broken down to short oligosaccharides. Proteus vulgaris produces two such lyases, ABC lyase I and II, with molecular weights of 112-113 kDa. Diffraction-quality crystals of both enzymes have been obtained by the hanging-drop vapour-diffusion method. ABC lyase I crystallizes in space group P2(1)2(1)2(1), with unit-cell parameters a = 49.3, b = 95.1, c = 230.0 A, Z = 4, and diffracts to 1.9 A resolution. Crystals of ABC lyase II belong to space group P1, with unit-cell parameters a = 64.2, b = 64.3, c = 142.1 A, alpha = 95.7, beta = 98. 1, gamma = 95.5 degrees, Z = 2; diffraction extends to at least 2.1 A.

Accumulation of copper in the liver and hepatic injury in chronic hepatitis C

BACKGROUND AND AIMS

Relationships between chronic liver disease and trace metals have not been clearly understood. To examine connections between severity of hepatic fibrosis in chronic hepatitis C and copper, iron and zinc we measured the contents of these metals in liver tissue and serum in the patients.

METHODS

Forty-one patients (26-62 years), 13 with fibrosis representing grade F1, 16 with F2, seven with F3, and five with F4, entered this study. Metals were quantified in needle liver-biopsy specimens by particle-induced X-ray emission. In serum, metals were measured by flameless atomic absorption spectrometry.

RESULTS

Hepatic copper content increased with progression of hepatic fibrosis (P < 0.05). The copper content correlated positively with bilirubin (r = 0.466, P = 0.0023), and with type IV collagen (r = 0.402, P = 0.0086) and correlated negatively with albumin (r = -0.404, P = 0.080). However, hepatic iron and zinc contents did not show a significant differences between grades of fibrosis.

CONCLUSIONS

Copper accumulation in fibrotic livers caused by chronic hepatitis C may contribute to hepatic injury. The real mechanism is not known at present, but excess copper may damage the liver by oxidative stress.

Effects of lipid-derivatized glycosaminoglycans (GAGs), a novel probe for functional analyses of GAGs, on cell-to-substratum adhesion and neurite elongation in primary cultures of fetal rat hippocampal neurons

The effects of glycosaminoglycans (GAG) on cell-to-substratum adhesion and neurite elongation were examined in primary cultures of fetal rat hippocampal neurons using tissue culture dishes coated with GAGs coupled to dipalmitoylphosphatidylethanolamine (PE), a novel probe for biological functions of GAGs. Both chondroitin sulfate conjugate to PE (CS-PE) and hyaluronic acid conjugate to PE (HA-PE) promoted neurite elongation from neurons in a dose-dependent manner when immobilized onto polylysine-coated dishes at various concentrations up to 1.0 microg/ml. The coating of CS-PE or HA-PE at a concentration higher than 1.0 microg/ml resulted in failure of neurite extension and adhesion of neurons to the substrata. In contrast, heparin conjugate to PE (HP-PE) did not exert any effects on neurite elongation or on cell attachment at these concentrations. These findings suggest that GAGs serve as a modulator for neurite elongation during neuronal network formation in the developing central nervous system.

Regulation of the gene promoter for extracellular signal-regulated protein kinase 2 by transcription factors NF-Y and Sp3

We have previously shown that the maximal promoter activity of the gene for extracellular signal-regulated protein kinase 2 (ERK2; also known as p42 mitogen-activated protein kinase) resides in the 371 bp 5'-flanking sequence. In the present study we defined roles for a CCAAT box and two adjacent GC boxes in the activity of this promoter. Deletion analysis and DNase I footprinting of this 371 bp region indicated that the CCAAT box at -64 and GC boxes at -86 and -39 are crucial for promoter activity. Electrophoretic mobility-shift assays showed that transcription factor NF-Y/CBF binds to the CCAAT box. Sp1 and Sp3, members of the Sp family of transcription factors, bind to the GC boxes of the ERK2 promoter. The binding of Sp3 was predominant over that of Sp1. Disruption by mutation of any of the CCAAT box and GC boxes similarly decreased promoter activity. These three cis elements exhibited a moderate synergy in promoter function. The transactivating role of NF-Y was corroborated by the finding that a dominant-negative form of NF-YA diminished the promoter activity. These results provide clues for refining our understanding of not only the regulation of expression of the gene for ERK2 but also mechanisms by which NF-Y and Sp1/Sp3 regulate transcription.

Hydrogen-isotopic compositions in Allan Hills 84001 and the evolution of the martian atmosphere

Hydrogen-isotopic compositions of carbonate and maskelynite in Allan Hills (ALH) 84001 were measured by secondary ion mass spectrometry (SIMS). The delta D values of both minerals show considerable deviation. The deviation seems to be caused by addition of varying amounts of terrestrial water in the case of carbonate. In the case of maskelynite, H is heterogeneously distributed and the deviation in delta D values seems to be due to mixing of this indigenous heavy H with isotopically normal H present in the SIMS chamber. The indigenous delta D value in ALH 84001 seems to be approximately 2000%. Carbonate rather than maskelynite seems to be the main carrier of H in ALH 84001. Because ALH 84001 is approximately 4 Ga old, the H-isotopic composition suggests that a large fraction of the initial martian atmosphere had already escaped by 4 Ga.

Terumo implantable left ventricular assist system: results of long-term animal study

The research group of Terumo Corporation, NTN Corporation, and the Setsunan University have been developing an implantable left ventricular assist system (T-ILVAS) featuring a centrifugal blood pump with a magnetically suspended impeller (MSCP). The present study describes results of chronic animal experiments using the MSCP. The MSCP has been tested ex vivo and in vivo in 6 sheep as a left heart bypass between the left ventricular apex and descending aorta. Ex vivo chronic sheep experiments using Model I demonstrated long-term durability, nonthrombogenicity, low hemolysis (<6 mg/dl), and excellent stability of the magnetic bearing with long-term survival for up to 864 days. Average pump flow rate was 4 L/min at a fixed rotational speed of 2000 rpm. Power spectral analyses of heart rate, aortic pressure, and blood temperature maintained normal 1/f fluctuation during the study. The retrieved pump was completely free from thrombus formation and there was no evidence of infarct in major organs. The implantable Model II was evaluated ex vivo in two sheep and intra-thoracically implanted in a sheep. These experiments were terminated at 70, 79, and 17 days due to blood leakage through the connector system within the housing. No thrombus formation was observed in any of the retrieved pumps. A modified Model II with a new connector system was subsequently intra-thoracically implanted in a sheep. The sheep survived for 482 days without any sign of thromboembolic complication or hemolysis at a fixed rotational speed of 1700 rpm and an average pump flow rate of 5 L/min. There was no intra-device thrombus formation or infarct in major organs. The Model III system, consisting of an implantable controller and a new MSCP with a reduced input power of 13 W, has been developed and implanted in a chronic sheep model. The MSCP was implanted in the left pleural space and the controller in the abdominal wall. The experiment is still in progress for more than 30 days without any significant complication to date. These animal studies strongly suggest the feasibility of the MSCP for use as long-term circulatory assist.

Parenchymal echo patterns of cirrhotic liver analysed with a neural network for risk of hepatocellular carcinoma

BACKGROUND

To objectively evaluate the parenchymal echo patterns of the liver in cirrhosis, an image analysing system in which a neural network is used has been found capable of numerically calculating coarse score (CS). Using this system, we analysed whether or not CS can serve as a predictive factor for the development of hepatocellular carcinoma (HCC).

METHODS

The risk factors for HCC were evaluated in 95 patients with liver cirrhosis with an average follow-up period of 2041 +/- 823 days. We used a three-layer feed-forward neural network and a back-propagation algorithm to calculate CS.

RESULTS

There were strong correlations between CS, alanine aminotransferase (ALT) and alpha-fetoprotein (AFP) and the average cumulative incidence rate of HCC evaluated by the Cox's proportional hazards model. The adjusted rate ratios were estimated to be 3.00, 2.80 and 2.01, respectively. The cumulative risks of HCC were significantly higher with an initial CS > or = 1.5 than with an initial CS < 1.5, with ALT > or = 80 IU/L than with initial ALT < 80 IU/L and with AFP > or = 20 ng/mL than with initial AFP < 20 ng/mL, all analysed by the log-rank test.

CONCLUSIONS

Coarse score is a useful predictor for development of HCC.

Recent progress in the development of Terumo implantable left ventricular assist system

The research group of the Terumo Corporation, the NTN Corporation, and Setsunan University (T. Akamatsu) has been developing an implantable left ventricular assist system (ILVAS) featuring a centrifugal blood pump with a magnetically suspended impeller (MSCP). The impeller of the MSCP is suspended by a magnetic bearing, providing contact-free rotation of the impeller inside the pump housing. Thus the MSCP is expected to provide years of long-term durability. Ex vivo chronic sheep experiments using the extracorporeal model (Model I) demonstrated long-term durability, nonthrombogenicity, and a low hemolysis rate (plasma free Hb <6 mg/dl) for more than 2 years. The prototype implantable model (Model II; 196 ml, 400 g) was evaluated ex vivo in 2 sheep and intrathoracically implanted in a small sheep (45 kg). These experiments were terminated at 70, 79, and 17 days, respectively, because of blood leakage through the connector system within the housing of Model II. There was no thrombus formation on the retrieved pump surfaces. A new connector system was introduced to the Model II pump (modified Model II), and the pump was intrathoracically implanted in a sheep. Pump flow rate was maintained at 3-7 L/min at 1700-1800 rpm. The temperature elevation on the surfaces of the motor and the electromagnet inside the pump casing was kept less than 6 degrees C. The temperature of the tissue adjacent to the pump casing became normal 10 days postoperatively. The sheep survived for more than 5 months without any sign of mechanical failure or thromboembolic complication. In vitro real-time endurance tests of motor bearings made of stainless steel and silicone nitride have been conducted for more than 1 year without any sign of bearing wear. The next prototype system (Model III), with an implantable controller and a new MSCP with reduced input power, has been developed with a view toward a totally implantable LVAS.

Small hepatocellular carcinoma: relationship of signal intensity to histopathologic findings and metal content of the tumor and surrounding hepatic parenchyma

PURPOSE

To investigate the relationship between the metal content of hepatocellular carcinoma (HCC) and the signal intensity pattern on magnetic resonance images.

MATERIALS AND METHODS

The signal intensity patterns of 59 HCCs 3 cm in diameter or smaller were correlated with histologic findings and metal content.

RESULTS

HCCs with high signal intensity on T1-weighted images demonstrated more steatosis (P = .035) and higher copper content (P = .008) than did surrounding hepatic parenchyma. HCCs with high signal intensity on T2-weighted images demonstrated more clear cells (P = .001) than did surrounding hepatic parenchyma. The higher signal intensities on T1-weighted and T2-weighted images were related to a higher and a lower degree of histologic differentiation, respectively. Multivariate analysis showed that the contrast-to-noise ratio between the HCC and surrounding hepatic parenchyma was affected by intratumoral copper content (P = .0338), zinc content of surrounding hepatic parenchyma (P = .0379), and the degree of histologic differentiation on T1-weighted (P = .0031) and T2-weighted (P = .0062) images.

CONCLUSION

The signal intensity of HCC on T1-weighted images is related to the degree of histologic differentiation, intratumoral copper content, and zinc content of surrounding hepatic parenchyma, whereas the signal intensity on T2-weighted images is related to the degree of histologic differentiation.

Natural course of small hepatocellular carcinoma with underlying cirrhosis. A study of 30 patients

To anticipate the prognosis and choose therapy for patients with relatively early-stage HCCs, we elucidate the natural course of such patients. Thirty cirrhotic patients with small hepatocellular carcinoma (HCC) < 3 cm in size and not receiving anti-cancer treatment were followed by sonography for periods of 6-48 mots. The growth speed varied considerably from case to case, with an average of 6.5+/-5.7 months of doubling time (DT). Growth speed of small HCC is significantly related to histological differentiation of tumors: a slow-growing HCC tends to be well-differentiated and a rapid-growing HCC moderately- or poorly-differentiated. Furthermore, there was a tendency to grow without changing from nodular type in slow-growing HCCs and to multiple nodular or massive types in intermediate- and rapid-growing HCCs. The survival rates of these untreated HCC patients showed a 1-yr survival of 90.7%, a 2-yr survival of 55.0%, and a 3-yr survival of 12.8%. Factors significantly influencing survival of these patients were serum total bilirubin level and DT. This study will provide invaluable data for diagnosing and treating for small HCCs.

A self-tuning effect of membership functions in a fuzzy-logic-based cardiac pacing system

This paper describes a self-tuning method of membership functions in a fuzzy-logic-based cardiac pacing system and validates its feasibility in a double sensor system which has minute ventilation and oxygen saturation level as its guides for the rate regulation. Though the agreement between the pacing rates (fuzzy rates) calculated with three linguistic variables for each parameter and the target rates were not satisfactory, it was improved significantly by tuning the membership functions. Almost the same evaluated values with those obtained by using six linguistic variables for each parameter were obtained. Time required for the self-tuning process was about 40 s (386CPU, 20 MHz) which was fast enough for the system. The smaller number of linguistic labels results in a smaller number of rules, which is beneficial in implantable cardiac pacemakers with limited memory capacity. A fuzzy-logic-based cardiac pacing system is promising for the realization of custom-made cardiac pacemakers.

An image analyzing system using an artificial neural network for evaluating the parenchymal echo pattern of cirrhotic liver and chronic hepatitis

To objectively evaluate the parenchymal echo pattern of cirrhotic liver and chronic hepatitis, we applied an image analyzing system (IAS) using a neural network. Autopsy specimens in a water tank (n = 13) were used to examine the relationship between the diameter of the regenerative nodule and the coarse score (CS) calculated by IAS. CS was significantly correlated with the diameter of the regenerative nodule (p < 0.0001, r = 0.966). CS is considered to be useful for evaluating the coarseness of the parenchymal echo pattern.

[Diagnosis and treatment for recurrent hepatocellular carcinoma]

In order to investigate the mechanism of recurrence of hepatocellular carcinoma (HCC), 322 patients with HCCs (size: < or = 3 cm) treated by percutaneous ethanol injection (PEI), transcatheter arterial embolization (TAE) or radiation therapy were evaluated. Cumulative recurrent rates of new lesions after the initial therapy were 25% (1-year), 57% (2-year) and 71% (3-year). In 116 patients whose tumors were multiple at the time of initial therapy, the recurrent rates were higher compared with 206 patients with a single tumor. In 228 of all patients, new lesions were observed in the noncancerous liver after initial therapy. We observed a single new lesion in 67% of the 134 patients, whose HCC was single at the time of initial therapy. In the remaining 33% of these patients, multiple new lesions were observed. As for the recurrence site, we found new lesions at a different segment of the liver from the initial HCC in 52% of these 134 patients. In the patients with multiple recurrent HCCs, the survival rates were lower in comparison with the patients whose recurrent HCC was single. In the patients whose new lesions were found within 1 year after the initial therapy, the survival rates were also lower compared with the patients whose new lesions were not detected during 1 year. In conclusion, the mechanism of multicentric occurrence may be closely correlated with the intrahepatic recurrence of HCC in consideration of the high incidence of recurrent rates of HCCs and their recurrent pattern.

[Repeated arterial infusion of zinostatin stimalamer using port for advanced hepatocellular carcinoma]

Four patients with advanced hepatocellular carcinoma were treated by repeated arterial infusion of zinostatin stimalamer (SMANCS). Every 4 weeks, 4 mg of SMANCS and 4 ml of Lipiodol were administered via the proper hepatic artery using an implantable arterial port. Three patients with advanced liver cirrhosis (Child B or C) could no longer be treated after 2 or 3 courses of SMANCS infusion because of hepatic failure. In the remaining patient also with compensated liver cirrhosis (Child A), a partial response was observed after 5 courses of chemo-infusion, but we discontinued infusion of SMANCS because of hepatic failure. To assess the usefulness of SMANCS for repeated arterial chemo-infusion by the port, we evaluated 103 patients with advanced HCC treated by Lipiodol emulsion mixed with 70 mg of epirubicin (EPI) using a port. An average course was 11 arterial infusions, and the overall response rate was 40%. One-year survival rates were 62% in Child A, 59% in Child B, and 53% in Child C. Compared with Child A and B patients, both elevation of serum total bilirubin levels and decrease of serum albumin levels were observed after 9 months in Child C patients. In conclusion, SMANCS may have more severe hepatic toxicity in comparison with Lipiodol emulsion mixed with EPI.

More than 1 year continuous operation of a centrifugal pump with a magnetically suspended impeller

The authors have been developing a centrifugal pump with a magnetically suspended impeller (MSCP) designed for total artificial heart and long-term ventricular support. The MSCP consists of a magnetic bearing, an impeller and housing, and a driving motor. The impeller is suspended by a magnetic bearing, therefore providing contact free rotation of the impeller inside the pump. This study was designed to evaluate long-term durability and nonthrombogenicity of the MSCP in a chronic sheep model. The blood contacting surfaces of the pump and conduits were completely modified by a heparin immobilization technique (Hepaface). The MSCP was placed paracorporeally as a left heart bypass between left ventricle and descending aorta in three adult sheep. Coumadin was given orally to maintain prothrombin time at 15-20 sec. The coagulation and hematologic parameters, including plasma free hemoglobin, were periodically monitored throughout the experiment. Under daily movement in the cage, the pump could produce average flow rates of 3-6 L/min (50-100 ml/kg) at 1,700-2,000 rpm. Although the arterial pulse contour decreased, there was no physiologic deterioration. The axial impeller excursion monitored by a position sensor was < 25 microns. Plasma free hemoglobin level remained at < 5 mg/dl throughout the experiment. There was no increase in the motor current, which indicates no massive thrombus formation around the impeller. One experiment was terminated at 70 days due to Hall sensor dysfunction of the motor. The retrieved pump was entirely free from thrombus formation. There was no detectable thrombus formation inside the pump or the inflow and outflow conduits. Hematologic, renal, and hepatic parameters remained within the normal range throughout the experiment. The other two sheep have survived for more than 395 and 41 days without major complication. These studies demonstrated that the MSCP has significant potential for long-term use.

The mouse extracellular signal-regulated kinase 2 gene. Gene structure and characterization of the promoter

ERK2 (extracellular-signal regulated kinase 2, also known as p42 mitogen-activated protein kinase) is an integral member of the mitogen-activated protein kinase cascade that is crucial for many cellular events such as proliferation and differentiation. Here, we determined the genomic organization of the Erk2 gene and characterized its promoter. The Erk2 gene spans over 60 kilobases, and the coding region is split into eight exons. In the coding region, exon-intron organization was exactly conserved between the two mouse genes for ERK2 and ERK1 except one junction shifted by one nucleotide. Primer extension and S1 nuclease analyses identified two major transcription start sites located at -219 and -223 relative to the translation start site. The 5'-flanking sequence lacked TATA box but contained a CCAAT box located approximately 60 base pairs upstream of transcription start sites. Sequencing of the 5'-flanking region also revealed potential cis-acting elements for multiple transcriptional regulatory factors including Sp1, zif268, Ets, CREB, and PuF sites. The promoter activity of the 5'-flanking region was examined using chloramphenicol acetyltransferase as a reporter gene. Transient transfection experiments using Chinese hamster ovary cells defined a maximal promoter activity in a 371-base pair region immediately upstream of the translation start site. Furthermore, we demonstrated, using mouse P19 embryonal carcinoma cells, that this 371-base pair sequence is likely to be sufficient to confer the transcriptional activation of the ERK2 promoter during the retinoic acid-induced differentiation of P19 cells.

Targeting of endopeptidase 24.16 to different subcellular compartments by alternative promoter usage

Endopeptidase 24.16 or mitochondrial oligopeptidase, abbreviated here as EP 24.16 (MOP), is a thiol- and metal-dependent oligopeptidase that is found in multiple intracellular compartments in mammalian cells. From an analysis of the corresponding gene, we found that the distribution of the enzyme to appropriate subcellular locations is achieved by the use of alternative sites for the initiation of transcription. The pig EP 24.16 (MOP) gene spans over 100 kilobases and is organized into 16 exons. The core protein sequence is encoded by exons 5-16 which match perfectly with exons 2-13 of the gene for endopeptidase 24.15, another member of the thimet oligopeptidase family. These two sets of 11 exons share the same splice sites, suggesting a common ancestor. Multiple species of mRNA for EP 24.16 (MOP) were detected by the 5'-rapid amplification of cDNA ends and they were shown to have been generated from a single gene by alternative choices of sites for the initiation of transcription and splicing. Two types of transcript were prepared, corresponding to transcription from distal and proximal sites. Their expression in vitro in COS-1 cells indicated that they encoded two isoforms (long and short) which differed only at their amino termini: the long form contained a cleavable mitochondrial targeting sequence and was directed to mitochondria; the short form, lacking such a signal sequence, remained in the cytosol. The complex structure of the EP 24.16 (MOP) gene thus allows, by alternative promoter usage, a fine transcriptional regulation of coordinate expression, in the different subcellular compartments, of the two isoforms arising from a single gene.

Leukocyte function-associated antigen 1-dependent adhesion of rat hepatoma AH66F cells and inhibition by protein kinase C inhibitors

When rat ascites hepatoma AH66F cells were incubated on a mesothelial cell (M-cell) layer for 1 hr, the adhesion rate of the cells to M-cells was ca. 46%. The protein kinase C (PKC) inhibitors, N-(2-methylpiperazyl)-5-isoquinolinesulfonamide (H-7) and N-ethoxycarbonyl-7-oxostaurosporine (NA-382), inhibited the adhesion of AH66F cells in a concentration-dependent manner, and the effect of NA-382 appeared after a treatment of more than 24 hr. The decreased adhesion rate after treatment with NA-382 for 48 hr was not further inhibited by addition of monoclonal antibodies of leukocyte function-associated antigen-1 (LFA-1) alpha- and beta-chains and intercellular adhesion molecule-1 (ICAM-1) (WT.1, WT.3, and 1A29, respectively). The expression of LFA- 1 alpha- and beta-chains on the surface of the plasma membrane of AH66F cells was decreased after treatment with NA-382 for 48 hr; treatment with a potent inhibitor of cyclic AMP-dependent protein kinase, N-[2-(p-bromocinnamylamino)ethyl]-5-isoquinolinesulfonamide (H-89), did not affect the cell adhesion and the expression of LFA-1 molecules on AH66F cells. These results suggest that the expression of LFA-1 molecules on AH66F cells is regulated through the PKC pathway.

Ultrastructure of cholesterol gallstones as observed by electron microscopy after freeze-fracturing

The ultrastructure of cholesterol gallstones (mixed type) was studied in detail for the first time under the transmission electron microscope after freeze-fracturing. Gallstones consisted essentially of cholesterol crystals, some impurities, and fluid. In accord with the theoretical 3.4 nm bilayered structure of cholesterol crystals, 3-4 nm periodicity of crystal layering was observed. However, gallstone cholesterol crystals were not perfect and often showed structural defects. Between crystals, complete edge-to-surface, edge-to-edge and surface-to-surface adhesions, and overall block-like aggregations were found. These may represent the structural basis for the stability of cholesterol crystal aggregation. The easy breakdown of cholesterol gallstones by extracorporeal shock wave lithotripsy is discussed in relation to their ultrastructure.

Inhibition of experimental metastasis and cell adhesion of murine melanoma cells by chondroitin sulfate-derivatized lipid, a neoproteoglycan with anti-cell adhesion activity

Chondroitin sulfate dipalmitoylphosphatidylethanolamine (CS-PE), when immobilized onto substratum, inhibited the adhesion of B16F10 mouse melanoma cells to fibronectin-coated dishes (anti-adhesion activity). CS-PE showed the most potent anti-adhesion activity for the melanoma cells among various GAG-PEs. CS-PE also inhibited the adhesion of B16F10 cells to Matrigel and the invasion of the cells into Matrigel. In the in vivo system of experimental metastasis, administration of B16F10 cells with CS-PE into C57BL/6 mice significantly inhibited lung metastasis. The inhibition degree of CS or hyaluronic acid-PE was lower than CS-PE. CS-PE administered intravenously into mice before the injection of B16F10 cells also inhibited metastasis. Pretreatment of B16F10 cells with CS-PE caused some but a lower degree of inhibition. When CS-PE was injected intravenously into mice, more binding in the lung was found than when CS was injected. CS-PE but not CS inhibited the retention in the lung of fluorochrome-labeled B16F10 cells when injected intravenously into mice. Since there was no significant effect of CS-PE on the viability and growth of B16F10 cells, the results suggest that CS-PE immobilized onto the subendothelial matrix may prevent melanoma cells from adhering to the subendothelial substrata of lung capillaries and inhibit subsequent invasion processes of metastasis.

Inhibition by protein kinase C inhibitor of expression of leukocyte function-associated antigen-1 molecules in rat hepatoma AH66F cells

To examine the mechanism of inhibition by protein kinase C (PKC) inhibitors of the adhesion of highly malignant hepatoma AH66F cells to the mesentery-derived mesothelial cell (M-cell) layer through leukocyte function-associated antigen-1 (LFA-1)/intercellular adhesion molecule-1, the effects of a PKC inhibitor, NA-382, on the expression of LFA-1 molecules in AH66F cells were examined and compared with those in thymocytes from normal rats. NA-382 inhibited the adhesion of AH66F cells to the M-cell layer and the expression of LFA-1 on the membrane of the hepatoma cells after treatment for more than 24 h. It was confirmed that AH66F cells express similar mRNAs for LFA-1 subunits to those of thymocytes, and their levels were also decreased after treatment with NA-382. On the other hand, the LFA-1 mediated adhesion and the expression of both protein and mRNA for LFA-1 subunits in thymocytes were not changed by the PKC inhibitor. These results suggest that the expression of LFA-1 molecules in AH66F cells may be regulated by PKC via quite different mechanisms from those in normal lymphocytes.

Highly malignant rat hepatoma AH66F cells respond to ascitic fluid

Rat ascites hepatoma (AH) 66F cells are more maligant than AH130 cells. AH66F cells grew faster than AH130 cells in media supplemented with both 5% fetal calf serum (FCS) and 5% ascites fluid (ASF), which is obtained from rats bearing these cells. The growth of AH66F cells was more accelerated in ASF than in FCS. The motility of AH66F cells was significantly increased by ASF, while the cells hardly moved in FCS. The growth and motility of AH130 cells were not different in FCS and ASF. Moreover, the adhesion ability of AH66F cells to mesothelial cells (M-cells) isolated from the mesentery was significantly higher than that of AH130 cells just after harvesting from the rats. The fresh AH66F cells adhered to M-cells at about 60%, and the adhesion rate of the cells decreased to about 47% after culturing with 5% FCS for 48 hours but was maintained in the presence of ASF. The adhesion ability of AH130 cells was not changed after incubation with both FCS and ASF. On the other hand, it has been reported that AH66F cells are unique in having leukocyte function-associated antigen-1 (LFA-1) on the outer cell membrane, adhering through interaction with intercellular adhesion molecule-1 (ICAM-1) on M-cells, although AH130 cells are not so efficient as other hepatoma cells. Consequently, the adhesion of AH66F cells to M-cells was inhibited by anti-LFA-1 beta-chain monoclonal antibody and anti-ICAM-1 antibody. When cells were cultured separately with FCS or ASF, and the adhesion molecules were analysed using flow cytometry, the expression of LFA-1 molecules on AH66F cells was not changed by eitherv FCS or ASF, but the ICAM-1 molecule on M-cells was increased time-dependently by ASF. From these results, the high malignancy of AH66F cells attributes to responsibility to ASF for tumor growth and motility and to irregular expression of LFA-1 on the membrane, in comparison to AH130 cells.

Effects of resistive load on the phase difference between chest and mouth flow in patients with chronic obstructive pulmonary disease

The influence of the resistive load on the phase difference (PD) between chest wall and mouth flow in patients with chronic obstructive pulmonary disease (COPD) was investigated, and the factors that induce an enlargement of the PD were assessed. After a resistance tube (R = 2.8 hPa/l/s) was applied to the mouth of the subjects, the PDs increased significantly both in normal (pre: 2.20 +/- 0.89, post: 5.60 +/- 2.04, P < 0.01) and in COPD (pre: 10.86 +/- 3.81; post: 13.12 +/- 3.64, P < 0.01). A significant correlation between the airway resistance and PD was noted (r = 0.730, P < 0.001). These results suggest that airway resistance is an important determinant for the PD. The predicted phase difference (PD') was then calculated by the Runge-Kutta method, using the measured chest flow, the time domain functions of airway resistance and the thoracic gas volume during a respiratory cycle, assuming that the respiratory system was a single compartment. The PD/PD' at pre-resistive load was significantly larger in COPD than in normal subjects (normal: 1.03 +/- 0.11; COPD, 1.45 +/- 0.19, P < 0.01), whereas the PD/PD' at a post-resistive load was significantly smaller than at the pre-resistive load in COPD patients. These results agree well with the two parallel or serial compartment model with inhomogeneous airway resistance, where the mechanical property of the partitioning tissue between the two compartments was taken into account. The pattern of the increase in the work energy consumed within the airway lumen calculated from this model was almost the same as for PD. Thus, we conclude that the PD may be a good index of the overload of the respiratory movement and available to predict muscle fatigue in COPD patients.

A protein kinase C inhibitor NA-382 prolongs the life span of AH66F-bearing rats as well as inhibiting leukocyte function-associated antigen-1 (LFA-1)-dependent adhesion of the cells

Rat ascites hepatoma AH66F is a high malignant tumor line, and AH66F-bearing rats died about 10 d after tumor inoculation. When treated with a protein kinase C (PKC) inhibitor, NA-382, the life span of AH66F-bearing rats was significantly prolonged, while a potent protein kinase A inhibitor, H-89, was not effective. In the adhesion assay, the adhesive ability to the mesentery-derived mesothelial cells (M-cells) of AH66F cells from rats injected with 10 mg/kg of NA-382 was significantly decreased, while the adhesion rate of the cells from the vehicle control group and from the H-89 (10 mg/kg)-treated group was about 50%. The adhesion of AH66F cells from the vehicle control group was curtailed to one half by leukocyte function-associated antigen-1 (LFA-1) beta-chain monoclonal antibody (WT.3), but that from the NA-382 group was not further influenced by WT.3. In flow cytometric analysis using WT.3, the expression of LFA-1 beta-chain on AH66F cells from the NA-382-treated group was also partially decreased, while that from the H-89-treated group was not changed. It was confirmed in vitro that after treatment with these protein kinase inhibitors for 48 h the expression of LFA-1 beta-chain in the cells was decreased by NA-382, but not by H-89. These results suggested that the PKC inhibitor prolongs the life span of AH66F-bearing rats through inhibition of LFA-1-dependent adhesion of the cells.