The role of chaperone complex HSP90-SGT1-RAR1 as the associated machinery for hybrid inviability between Nicotiana gossei Domin and N. tabacum L

Two cultured cell lines (GTH4 and GTH4S) of a Nicotiana interspecific F1 hybrid (N. gossei × N. tabacum) were comparatively analyzed to find genetic factors related to hybrid inviability. Both cell lines proliferated at 37 °C, but after shifting to 26 °C, GTH4 started to die similar to the F1 hybrid seedlings, whereas GTH4S survived. As cell death requires de novo expression of genes and proteins, we compared expressed protein profiles between the two cell lines, and found that NgSGT1, a cochaperone of the chaperone complex (HSP90-SGT1-RAR1), was expressed in GTH4 but not in GTH4S. Agrobacterium-mediated transient expression of NgSGT1, but not NtSGT1, induced cell death in leaves of N. tabacum, suggesting its possible role in hybrid inviability. Cell death in N. tabacum was also induced by transient expression of NgRAR1, but not NtRAR1. In contrast, transient expression of any parental combinations of three components revealed that NgRAR1 promoted cell death, whereas NtRAR1 suppressed it in N. tabacum. A specific inhibitor of HSP90, geldanamycin, inhibited the progression of hypersensitive response-like cell death in GTH4 and leaf tissue after agroinfiltration. The present study suggested that components of the chaperone complex are involved in the inviability of Nicotiana interspecific hybrid.

Development of an eyewear to measure eye and body movements

To enable precise detection of mental and physical states of users in a daily life, we have been developing an eyewear to measure eye and body movement in a unrestricted way. The horizontal and vertical EOG (electrooculogram) signals are measured and amplified with three metal dry electrodes placed near nasion and both sides of rhinion, of which positions correspond to the bridge and nose pads of eyewear, respectively. The user's mental states like drowsiness, sleepiness, fatigue, or interest to objects can be identified by the movements and blinking of the eyes extracted from the measured EOG. And the six-axis motion sensor (three-axis accelerometer and three-axis gyroscope) mounted in the eyewear measures the body motion. As the sensor located near the head is on the body axis, this eyewear is suitable to measure user's movement or shift of center of gravity during physical exercise with a high precision. The measured signals are used to extract various events of eye and body movement by the mounted microcontroller chip, or can be transmitted to the external devices via Bluetooth communication. This device can enable you to look into "yourself", as well as outer scenes. In this presentation, the outline of the eyewear is introduced and some possible applications are shown.

Acute Toxicity and Genotoxicity Studies of a Microbial Transglutaminase

Transglutaminase is a naturally occurring and ubiquitous enzyme which is responsible for the transfer of acyl groups (and resulting crosslinking) between glutamine and lysine residues. Commercial use has been precluded due to the lack of availability and several undesirable characteristics of the mammalian derived enzyme. The recent availability of microbially derived transglutaminase ensures the increased likelihood of human exposure to this substance. In this first of a series of articles evaluating the safety of microbial-deriv ed transglutaminase, the enzyme was tested for acute oral toxicity in the rat and for its mutagenic potential. The acute toxic potential appears to be relatively low given the lack of mortality, morbidity, or signs of toxicity at doses of le; 2,000 mg / kg body weight (bw). Similarly, the enzyme appears to have little if any potential for mutagenesis having been tested in four strains of Salmonella typhimurium (TA98, TA100, TA1535, and TA1537), one tryptophan-dependent Escherichia coli strain (WP2uvrA), with and without activation, the Chinese hamster lung cell line (CHL), with and without activation, and for chromosomal abnormalities in the Slc:ddY male mouse (micronucleus); in all cases found to be without obvious effects. These findings are not surprising given the fact that enzymes are generally considered to be of low toxic potential.

Enhancement of antibody production by growth factor addition in perfusion and hollow-fiber culture systems

The effects of the high-molecular-weight growth factors, transferrin and bovine serum albumin (BSA), on antibody production were analyzed quantitatively in continuous hollow-fiber cultivation over a period of 60 days. Transferrin enhanced cell growth but had no significant effect on the specific antibody production rate, whereas BSA significantly enhanced antibody production. The antibody production rate was increased 4- and 14-fold respectively by feeding BSA at 2 and 5 g L(-1) into the EC side of the system (the side connected to the cell-containing outer part of the hollow-fiber unit) compared with the production achieved without BSA. Addition of 5 g L(1) BSA into the IC side of the system (the side connected to the inner part of the hollow-fiber unit) resulted in a 2.5-fold increase in the antibody production rate. The effect of BSA was also analyzed using the perfusion culture system with a separation unit. When fresh medium containing either 2 or 5 g L(-1) BSA was fed into the reactor, both the specific growth rate and specific death rate increased, while the specific antibody production rate was increased 2- and 25-fold, respectively, by feeding BSA at these two concentrations compared with no addition. Comparing the two systems, the increase in the antibody production rate achieved with the hollow-fiber system was threefold greater than that in the perfusion culture system with the same concentration of BSA feeding. (c) 1995 John Wiley & Sons, Inc.

Maximum virginiamycin production by optimization of cultivation conditions in batch culture with autoregulator addition

A strategy for optimization of non-growth-associated production in batch culture employing an empirical approach was developed through the study of virginiamycin production. The strategy is formulated with two aims: attaining a high cell concentration at the beginning of the production phase without decrease in production activity; and enhancing the production activity during the production phase. As a practical example, the goal of a maximum virginiamycin (M and S) production in the batch culture of Streptomyces virginiae was set. To attain a high cell concentration in the production phase of the batch culture, that is, to extend the growth phase for as long as possible, the optimum composition and concentration of the complex medium, especially the yeast extract (YE) concentration, were first investigated. Dissolved oxygen (DO) concentration control was also a parameter considered in maintaining the production activity during the production phase. In addition, to enhance the production activity, an optimum addition strategy of an autoregulator, virginiae butanolide-C (VB-C), was investigated. Combining these measures, the optimum cultivation conditions were found to be an initial YE concentration in the complex medium of 45 g/L, the shot addition of 300 mug/L of VB-C 11.5 h after the start of the batch culture, and a DO concentration maintained above 2 mg/L. The maximum concentrations of virginiamycin M and S were about ninefold those obtained under nonoptimum cultivation conditions. Nonoptimum cultivation conditions consisted of an initial YE concentration one sixth (7.5 g/L) that of the optimum cultivation conditions, and no VB-C addition. These conditions were used as representative of the standard cultivation of virginiamycin in this study. The strategy developed here will be applicable to the production of other antibiotics, especially to the cultivation of Streptomyces species, in which a hormonelike signal material (an autoregulator) plays an important role in antibiotic production. (c) 1996 John Wiley & Sons, Inc.

Comparative analysis of transcriptional responses to saline stress in the laboratory and brewing strains of Saccharomyces cerevisiae with DNA microarray

To construct yeast strains showing tolerance to high salt concentration stress, we analyzed the transcriptional response to high NaCl concentration stress in the yeast Saccharomyces cerevisiae using DNA microarray and compared between two yeast strains, a laboratory strain and a brewing one, which is known as a stress-tolerant strain. Gene expression dynamically changed following the addition of NaCl in both yeast strains, but the degree of change in the gene expression level in the laboratory strain was larger than that in the brewing strain. The response of gene expression to the low NaCl concentration stress was faster than that to the high NaCl concentration stress in both strains. Expressions of the genes encoding enzymes involved in carbohydrate metabolism and energy production in both strains or amino acid metabolism in the brewing strain were increased under high NaCl concentration conditions. Moreover, the genes encoding sodium ion efflux pump and copper metallothionein proteins were more highly expressed in the brewing strain than in the laboratory strain. According to the results of transcriptome analysis, candidate genes for the creation of stress-tolerant strain were selected, and the effect of overexpression of candidate genes on the tolerance to high NaCl concentration stress was evaluated. Overexpression of the GPD1 gene encoding glycerol-3-phosphate dehydrogenase, ENA1 encoding sodium ion efflux protein, and CUP1 encoding copper metallothionein conferred high salt stress tolerance to yeast cells, and our selection of candidate genes for the creation of stress-tolerant yeast strains based on the transcriptome data was validated.

Maximizing yellow pigment production in fed-batch culture of Monascus sp

Yellow pigment production in exponential fed-batch cultivation of Monascus sp. was studied. Due to the difficulty of measuring the optical density for accurate determination of the cell concentration, a capacitance probe was employed on-line. The feed rate needed to keep the specific growth rate, mu, constant in fed-batch culture was determined on the basis of the cell concentration measured by the capacitance probe. Control of mu was improved by using updated information on the cell concentration compared with the simple feed-forward determination method using the initial cell concentration only. The highest specific pigment production rate was achieved with a mu of 0.02 h(-1) in the feeding phase. However, among several fermentation examined, the largest pigment production in the final step was obtained at a mu of 0.01 h(-1); in each case the same amount of substrates was used. An investigation of the optimal initial glucose concentration revealed that pigment production was maximum when the initial glucose concentration in the batch mode was 10 g/l and mu was 0.01 h(-1) in the fed-batch mode. It was also found that the pellet weight in the fermentation could be accurately estimated by image analysis. The ratio of the mycelium weight to the total cell weight estimated from information on the total cell weight and the estimated pellet weight was found to be more than 80%. However, no clear quantitative relationship could be discerned between the specific pigment production rate, rho, and the ratio of mycelium in the cell population.

Effects of the changes in enzyme activities on metabolic flux redistribution around the 2-oxoglutarate branch in glutamate production by Corynebacterium glutamicum

An experimental method for metabolic control analysis (MCA) was applied to the investigation of a metabolic network of glutamate production by Corynebacterium glutamicum. A metabolic reaction (MR) model was constructed and used for flux distribution analysis (MFA). The flux distribution at a key branch point, 2-oxoglutarate, was investigated in detail. Activities of isocitrate dehydrogenase (ICDH), glutamate dehydrogenase (GDH), and 2-oxoglutarate dehydrogenase complex (ODHC) around this the branch point were changed, using two genetically engineered strains (one with enhanced ICDH activity and the other with enhanced GDH activity) and by controlling environmental conditions (i.e. biotin-deficient conditions). The mole flux distribution was determined by an MR model, and the effects of the changes in the enzyme activities on the mole flux distribution were compared. Even though both GDH and ICDH activities were enhanced, the mole flux distribution was not significantly changed. When the ODHC activity was attenuated, the flux through ODHC decreased, and glutamate production was markedly increased. The flux control coefficients of the above three enzymes for glutamate production were determined based on changes in enzyme activities and the mole flux distributions. It was found that the factor with greatest impact on glutamate production in the metabolic network was obtained by attenuation of ODHC activity.

[Platelet activation in obstructive sleep apnea syndrome]

The incidences of cardiovascular and cerebrovascular diseases are reportedly higher in patients with obstructive sleep apnea (OSA) than in OSA-free subjects, though the mechanism remains unknown. Recently, the contribution of activated platelets to a number of pathological conditions such as stroke or ischemic heart disease has been suggested. We hypothesized that the expression of activated platelet markers resulting from OSA might be higher than in healthy subjects. By flow cytometry using monoclonal antibodies, we measured two such markers, PAC-1 and CD 62 P, in OSA patients and healthy subjects. Twelve healthy men (age, 52.7 +/- 12.8 y/o; and body mass index (BMI), 22.2 +/- 16.1 kg/m2; mean +/- S.D.) and 20 male patients with OSA (age, 50 +/- 7.96 y/o; BMI, 28.1 +/- 3.3 kg/m2; apnea hypopnea index (AHI), 38.2 +/- 21.2 times/hr; and lowest SpO2, 75.6 +/- 11.3%) were enrolled in this study. PAC-1 expression was significantly higher in OSA patients (65.1 +/- 17.8%) than in healthy subjects (16.8 +/- 7.4%), as was CD 62 P expression (8.5 +/- 8.8% vs. 0.88 +/- 0.57%). The increase in PAC-1 expression was correlated with AHI and the arousal index. These findings suggest that activated platelet markers could be good indicators for untreated OSA.

Modelling and optimization of environmental conditions for kefiran production by Lactobacillus kefiranofaciens

A mathematical model for kefiran production by Lactobacillus kefiranofaciens was established, in which the effects of pH, substrate and product on cell growth, exopolysaccharide formation and substrate assimilation were considered. The model gave a good representation both of the formation of exopolysaccharides (which are not only attached to cells but also released into the medium) and of the time courses of the production of galactose and glucose in the medium (which are produced and consumed by the cells). Since pH and both lactose and lactic acid concentrations differently affected production and growth activity, the model included the effects of pH and the concentrations of lactose and lactic acid. Based on the mathematical model, an optimal pH profile for the maximum production of kefiran in batch culture was obtained. In this study, a simplified optimization method was developed, in which the optimal pH profile was determined at a particular final fermentation time. This was based on the principle that, at a certain time, switching from the maximum specific growth rate to the critical one (which yields the maximum specific production rate) results in maximum production. Maximum kefiran production was obtained, which was 20% higher than that obtained in the constant-pH control fermentation. A genetic algorithm (GA) was also applied to obtain the optimal pH profile; and it was found that practically the same solution was obtained using the GA.

Multivariable control of alcohol concentrations in the production of polyhydroxyalkanoates (PHAs) by Paracoccus denitrificans

A novel multivariable control strategy is developed for alcohol (ethanol and n-pentanol) concentrations in the production of poly(3-hydroxybutyrate-co-3-hydroxyvalerate), P(HB-co-HV), a biodegradable polymer by Paracoccus denitrificans ATCC 1774. This controller, which is developed to control the mole fraction of P(HB-co-HV), consists of two parts: one is for ethanol concentration control and the other is for mole fraction control, based on the concept of metabolic flux distribution control. A simple metabolic reaction (MR) model is constructed for flux distribution analysis. The relationship between mole ratio of specific consumption rate of the two alcohols (ethanol and n-pentanol) and the mole fraction of 3HV units in the polymer is linear. This result suggests that the split ratio at a branched point of 3-ketovaleryl-CoA in the P(HB-co-HV) synthetic pathway is constant for several fermentation conditions. When the mole fraction of 3HV units has a target value, the feed rate of n-pentanol becomes a function of the feed rate of ethanol and the set value of 3HV, based on the MR model. The mole fraction of 3HV units successfully reached the target value using this strategy. The mole fraction control strategy is combined with an optimal production strategy based on the optimal profile of the specific growth rate. The combined strategy is realized using multivariable controllers and P(3HB-co-3HV) production is maximized with a given value of mole fraction of 3HV units at the final step of fermentation.

Effects of age on muscle energy metabolism and oxygenation in the forearm muscles

PURPOSE

The effects of aging on muscle metabolism and oxygenation have not yet been elucidated. We evaluated the effects of aging on energy metabolism and oxygenation in sedentary healthy subjects by simultaneously measuring 31P-magnetic resonance spectroscopy (MRS) and near-infrared spectroscopy (NIRS).

METHODS

Nine young (28.1 +/- 5.0 yr) and nine older (61.4 +/- 4.6 yr) healthy subjects were studied. The 31P-MR spectrum was obtained every 15 s during and after hand gripping exercise. Intracellular pH (pHi) and PCr/(PCr+Pi) [PCr: phosphocreatine, Pi: inorganic phosphate] were calculated as an index of energy metabolism. The time constant of the PCr/(PCr+Pi) recovery (tau PCr) was calculated. With NIRS, we evaluated the recovery rates of oxygenated (RHbO2) and deoxygenated hemoglobin (RHb) during the initial 10 s of recovery.

RESULTS

The PCr/(PCr+Pi) and pHi at rest and at completion of the exercise and tau PCr did not differ between young and older subjects. However, RHbO2 and RHb were significantly slower in older subjects than in young subjects.

CONCLUSIONS

The results suggest that muscle energy metabolism in the forearm muscle was not affected by aging. The slower RHbO2 and RHb in older subjects suggested impaired O2 supply, which was probably due to impaired peripheral circulation caused by the process of aging.

Curative resection of both primary and second primary lung cancer

Curative resection of a second primary lung cancer in a patient who survived small-cell lung cancer is reported. Small-cell cancer had been treated with chemotherapy followed by surgical resection 12 years before. The patient developed squamous cell cancer as the second primary tumor and underwent lobectomy with mediastinal node dissection. Patients who undergo two curative pulmonary resections of both primary and second primary lung cancer are extremely rare. The patient is alive 176 months after the initial diagnosis of small-cell lung cancer and 28 months after resection for his second primary lung cancer. Careful follow-up at an interval of 3-6 months beyond 10 years is very important because adequate treatments could lead to longer survival of patients with primary small-cell lung cancer.

Characterization of Bacteriocin N15 Produced by Enterococcus faecium N15 and Cloning of the Related Genes

Enterococcus faecium N15 was isolated from nuka (Japanese rice-bran paste), which is utilized as starter in the fermenting of vegetables, and was found to produce a bacteriocin that exhibited a broad spectrum of activity, including activity against Listeria monocytogenes and Bacillus circulans JCM2504. The bacteriocin was sensitive to proteases (alpha-chymotrypsin, proteinase K, trypsin, and pepsin) and alpha-amylase, but it was resistant to lipase. The bacteriocin was resistant to heat treatment at 100 degrees C for 2 h, but its activity was completely lost after autoclaving at 121 degrees C for 15 min. It was active over a wide pH range from 2.0 to 10.0. The bacteriocin showed bactericidal activity against Lactobacillus sake JCM1157 at a concentration of 40 AU/ml. Its molecular weight was estimated by SDS-PAGE to be about 3-5 kDa. PCR primers were designed based on the conserved amino acid sequences of class IIa bacteriocins. A 3-kb DNA fragment was amplified and three open reading frames (ORFs) were found. The first encodes a probable immunity protein of 103 amino acid residues and shows complete homology with the putative immunity protein of E. faecium DPC1146. The second and third ORFs respectively encode a probable transposase gene and an inducing factor. The upstream region of the immunity gene, in which the bacteriocin structural gene is located, was amplified. A homology search revealed that the bacteriocin produced by E. faecium N15 exhibits complete identity to enterocin A, a bacteriocin produced by E. faecium DPC1146. PCR using the primers designed in this study is a rapid and sufficient method of screening for bacteriocin-producing strains.

Increased production of nitrotyrosine in lung tissue of rats with radiation-induced acute lung injury

The purposes of this study were 1) to identify the nitric oxide (NO) synthase (NOS) isoform responsible for NO-mediated radiation-induced lung injury, 2) to examine the formation of nitrotyrosine, and 3) to see whether nitrotyrosine formation and lung injury are reduced by an inducible NOS (iNOS) inhibitor, aminoguanidine. The left hemithorax of rats was irradiated (20 Gy), and the degree of lung injury, the expression of NOS isoforms, and the formation of nitrotyrosine and superoxide were examined after 2 wk. iNOS mRNA was induced, and endothelial NOS mRNA was markedly increased in the irradiated lung. Nitrotyrosine was detected biochemically and immunohistochemically. Aminoguanidine prevented acute lung injury as indicated by decreased protein concentration and lactate dehydrogenase activity in bronchoalveolar lavage fluid and improved NMR parameters and histology. Furthermore, the formation of nitrotyrosine was significantly reduced in the aminoguanidine group. We conclude that iNOS induction is a major factor in radiation-induced lung injury and that nitrotyrosine formation may participate in the NO-induced pathogenesis.

Implication of ESR signals from ceruloplasmin (Cu(2+)) and transferrin (Fe(3+)) in pleural effusion of lung diseases

Pleural effusions of seven lung cancer patients (mean age; 58) and seven non-cancer patients (mean age; 49) were examined and Cu(2+) was measured in ceruloplasmin and Fe(3+) in transferrin signals by electron spin resonance (ESR) method. The variations of total Fe and Cu ions, ceruloplasmin and transferrin, proteins, neutrophil cell counts, LDH and nitrite/nitrate were also examined. The Cu(2+) peak was decreased and the Fe(3+) peak was increased in the cancer group. The interrelationship among Cu(2+), total Cu and ceruloplasmin, and among Fe(3+), total Fe and transferrin clarified that Cu(2+) and Fe(3+) are not a representative of ceruloplasmin and transferrin, respectively. The ratio of Cu(2+)/Fe(3+) in pleural effusion distinguished lung cancer from benign inflammation as a cause. The ratio of total Cu/total Fe measured by the chemical analysis method also distinguished these, but the ratio of ceruloplasmin/transferrin was unable to distinguish the cancer. In conclusion, the simple and rapid measurement of Cu(2+)/Fe(3+) by ESR effectively abstracts the variation of total ion concentrations caused by malignant disease.

In vivo Hahn spin-echo decay (Hahn-T2) observation of regional changes in the time course of oleic acid lung injury

We studied the time course of changes in the Hahn spin-echo decay (Hahn-T2) in lungs of spontaneously breathing living rats at 1 hour, 3 hours, and 7 days following oleic acid injection. Motion artifacts were minimized by using the motion-insensitive interleaved rapid line scan (ILS) imaging technique. Prior to injury, the lungs exhibited two resolvable exponential Hahn-T2 components. One and 3 hours after injury the decay showed a regionally nonuniform behavior, which was fit with one, two, or three exponential components. The short and medium components increased at 1 and 3 hours after injection. The third, much longer, component is probably due to intraalveolar pulmonary edema. After 7 days the Hahn decay was similar to that observed before injury, probably reflecting resolution of the edema. Our data suggest that Hahn-T2 measurements can be used to characterize the time course and regional distribution of lung injury in living animals.

A maximum production strategy of lysine based on a simplified model derived from a metabolic reaction network

The aim of this study is to develop a strategy for maximum production of a target product with a simplified model derived from a metabolic reaction network through an example of lysine production. Based on the model, a search for the optimal specific growth rate profile was conducted among the available conditions of batch fermentation based on the derived model, when the total fermentation time was fixed. The optimal specific growth rate was obtained as a boundary control: initially, the specific growth rate was maintained at a maximum value and was subsequently switched to a critical value giving the maximum specific production rate. To make the specific growth rate follow this optimal profile as accurately as possible in batch mode, first, an appropriate initial concentration of leucine was employed in the experiment. Second, the feeding strategy of leucine was further studied. The specific growth rate profile with feeding was closer to the optimal one and the amount of lysine produced at the final stage of fermentation was increased about twofold, compared to that in the batch fermentation. Finally, the strategy was summarized as an algorithm for general use of this method.

Nisin production by a mixed-culture system consisting of Lactococcus lactis and Kluyveromyces marxianus

To control the pH during antimicrobial peptide (nisin) production by a lactic acid bacterium, Lactococcus lactis subsp. lactis (ATCC11454), a novel method involving neither addition of alkali nor a separation system such as a ceramic membrane filter and electrodialyzer was developed. A mixed culture of L. lactis and Kluyveromyces marxianus, which was isolated from kefir grains, was utilized in the developed system. The interaction between lactate production by L. lactis and its assimilation by K. marxianus was used to control the pH. To utilize the interaction of these microorganisms to maintain high-level production of nisin, the kinetics of growth of, and production of lactate, acetate, and nisin by, L. lactis were investigated. The kinetics of growth of and lactic acid consumption by K. marxianus were also investigated. Because the pH of the medium could be controlled by the lactate consumption of K. marxianus and the specific lactate consumption rate of K. marxianus could be controlled by changing the dissolved oxygen (DO) concentration, a cascade pH controller coupled with DO control was developed. As a result, the pH was kept constant because the lactate level was kept low and nisin accumulated in the medium to a high level compared with that attained using other pH control strategies, such as with processes lacking pH control and those in which pH is controlled by addition of alkali.

Modeling and optimization of alpha-amylase production in a recombinant yeast fed-batch culture taking account of the cell cycle population distribution

A simple mathematical model describing the cell cycle dependency of rice alpha-amylase production by a recombinant yeast was constructed to investigate the efficiency of cell cycle population control. First, the effects of the glucose concentration and cultivation temperature on the specific growth rate, the specific production rate of rice alpha-amylase, and the distribution of the cell cycle population were studied under balanced growth conditions. On the basis of the results, parameter values for the mathematical model were then estimated. The proposed model was shown to be applicable for unbalanced as well as balanced growth phases. The optimal control strategy in respect of temperature and glucose concentration for maximum rice alpha-amylase production, taking into account the cell cycle population, was determined and the result was compared with that obtained by a simple mathematical model in which cell cycle distribution was not considered. Finally, the effect of the initial population of each cell cycle phase on the final amount of the product under optimal operational conditions was investigated. The simulation and experimental data coincided well with each other, and the model was used to optimize the control strategy for maximum alpha-amylase production.

Maximum production strategy for biodegradable copolymer P(HB-co-HV) in fed-batch culture of Alcaligenes eutrophus

A novel strategy for the maximum production of a biodegradable copolymer, poly(3-hydroxybutyric-co-hydroxyvaleric) acid, P(HB-co-HV), was developed, based on the kinetic parameters obtained from fed-batch culture experiments of Alcaligenes eutrophus. The effects of various culture conditions such as mole ratio of carbon:nitrogen in feed medium (C/N); total fatty acids concentrations; and addition ratio of fatty acids on cultivation properties such as the specific rates of cell formation, mu (h-1), P(HB-co-HV) production, rho[g.P(HB-co-HV)/g.cell/h], production yield from fatty acids [g.P(HB-co-HV)/g.fatty acid], and mole fraction of monomeric units in the copolymer [mol.(HV)/{mol.(HB) + mol.(HV)}], were investigated. When nitrogen supply was sufficient for cell growth; that is, C/N (mol.nitrogen atom/mol.carbon atom) was low, mu was high, but rho and the production yield were low, because fatty acids were used mainly for energy formation and anabolic reactions in the cells. On the other hand, when nitrogen supply was limited for cell growth-that is, C/N was high-rho was high. The highest value of rho was obtained when C/N was 75. As the mole ratio of valeric acid (VA) to butyric acid (BA) in the feed medium was increased, the mole fraction of HV units in P(HB-co-HV) increased linearly. When the ratio of BA to VA in the feed medium was kept at a constant value, but C/N was increased, the mole fraction of HV units decreased. In particular, when C/N was >12, the mole fraction of HV units decreased linearly as C/N increased. When VA was utilized as the sole carbon source and C/N was fixed at 4, P(HB-co-HV) with the highest mole fraction of HV units (67 mol%) was achieved. From these results, it was shown that both C/N and the mole ratio of BA to VA in the feed medium should be well controlled for an optimal production of P(HB-co-HV) with the desired value of the mole fraction of HV units. When the addition ratio of butyric acid was 50 wt% of total fatty acids, a maximum production strategy for P(HB-co-HV) was developed and realized experimentally, which was based on a model of the relationship between mu and rho.

Separation of deterrents to ingestive behavior of cattle from cattle feces

Feeding-deterrent chemicals were extracted from cattle feces and then separated with three chromatographic methods. Behavioral two-choice test bioassays with cattle were used to examine the deterrent properties of the fractions. Cattle feces were extracted with diethyl ether, and the extracts were separated into neutral, acidic, and basic fractions. Of the three fractions, only the neutral fraction was a deterrent. Separation of the ether-soluble neutral chemicals was conducted with an open column of silica gel using four carrier solutions consisting of pentane and ether. Fraction B (eluted with the carrier solution; pentane:ether = 90:10) was the most effective deterrent among the four fractions. This fraction was divided into 10 fractions by liquid chromatography. Fractions 6, 7, and 8 seemed to deter cattle from feeding. The combined Fractions 6, 7, and 8 were separated into 15 fractions with HPLC. Deterrent activities were detected in Fractions 2, 3, 9, 10, 11, 12, 13, and 14, suggesting that deterrents were separated into two groups using HPLC. These results suggested that several specific chemicals in feces are involved in inhibiting cattle from ingesting grass near cattle feces.

Optimization of agitation and aeration conditions for maximum virginiamycin production

To maximize the productivity of virginiamycin, which is a commercially important antibiotic as an animal feed additive, an empirical approach was employed in the batch culture of Streptomyces virginiae. Here, the effects of dissolved oxygen (DO) concentration and agitation speed on the maximum cell concentration at the production phase, as well as on the productivity of virginiamycin, were investigated. To maintain the DO concentration in the fermentor at a certain level, either the agitation speed or the inlet oxygen concentration of the supply gas was manipulated. It was found that increasing the agitation speed had a positive effect on the antibiotic productivity independent of the DO concentration. The optimum DO concentration, agitation speed and addition of an autoregulator, virginiae butanolide C (VB-C), were determined to maximize virginiamycin productivity. The optimal strategy was to start the cultivation at 450 rpm and to continue until the DO concentration reached 80%. After reaching 80%, the DO concentration was maintained at this level by changing the agitation speed, up to a maximum of 800 rpm. The addition of an optimal amount of the autoregulator VB-C in an experiment resulted in the maximal production of virginiamycin M (399 mg/l), which was about 1.8-fold those obtained previously.

Time domain reflectometry: measurement of free water in normal lung and pulmonary edema

The free water content of lung tissue was investigated by dielectric spectroscopy in normal lungs and in pulmonary edema induced by oleic acid in rats. The dielectric relaxation in a frequency range of 10(7) to 10(10) Hz was measured with the time domain reflectometry method at 25 degreesC. Three dielectric relaxation processes were analyzed for the lung tissue. A high-frequency process around 10 GHz was attributed to the orientation of free water molecules based on the relaxation time [log tauh (in s) = -11.03]. The dielectric strength (Delta epsilon) of this high-frequency peak (Delta epsilonh) should reflect the amount of free water in the tissue. Because the measured Delta epsilonh depended on the air content of the lung samples, the value of Delta epsilonh was corrected for the air content of each sample as determined by the point-counting method in the area where the time domain reflectometry data were obtained. The lungs of rats that received an injection of oleic acid had a significantly increased free water content [(Delta epsilonh of lung/Delta epsilon of pure water) x density of pure water] compared with that in the normal lung (0.76 vs. 0.59 g/cm3). These results indicate that free water occupies approximately 60% of the total volume of normal lung tissue and that there is an increase in free water in pulmonary edema.

Knowledge-based design and operation of bioprocess systems

Almost twenty years have passed since the first applications of the knowledge-based approach to bioprocess operations were reported. During this period, approaches such as fuzzy logic, artificial neural network modeling, expert systems and genetic algorithms have been extensively studied and successfully used in the design and control of various bioprocesses. The recent development of these approaches in the design and operation of biological processes is summarized and reviewed, especially focusing on the studies reported in biochemical engineering journals.

The importance of polymorphonuclear leukocytes in lipopolysaccharide-induced superoxide anion production and lung injury: ex vivo observation in rat lungs

The purpose of this study is to determine if the polymorphonuclear leukocyte (PMN) is a major causative agent for lipopolysaccharide (LPS)-induced lung injury and responsible for the excess production of superoxide anion in the lung. We measured superoxide anion production from the lung and pulmonary capillary permeability in rats with and without PMN depletion. The superoxide anion production from the lung was measured using a purpose-built ex vivo chemiluminescence apparatus. Pulmonary capillary permeability was evaluated by the Evans blue dye extravasation method. PMN sequestration was determined by counting PMNs in histologic tissue specimens using microscopy. All rats received 3 mg/kg LPS intravenously. Examinations were undertaken at 2, 6, and 12 h after the LPS injection. The PMN-depleted group received cyclophosphamide 4 days before the LPS injection, which resulted in a PMN count of less than 200 cells/microliter. In rats without PMN depletion, Evans blue dye extravasation increased significantly at 12 h after the LPS injection; PMN sequestration increased at 2, 6, and 12 h after the LPS injection; and superoxide anion production increased at 6 h and remained elevated at 12 h after the LPS injection. The increased permeability, PMN sequestration, and superoxide anion production were not seen in the PMN-depleted group. The contribution of the xanthine/xanthine oxidase system and alveolar macrophages to the observed superoxide anion production was negligible. We conclude that, in rats, the PMN is a major causative agent in LPS-induced lung injury and is responsible for the excess production of superoxide anion in the lung.

Bioprocess fault detection by nonlinear multivariate analysis: application of an artificial autoassociative neural network and wavelet filter bank

A nonlinear multivariate analysis, artificial autoassociative neural network (AANN), was applied to bioprocess fault detection. In an optimal production process of a recombinant yeast with a temperature controllable expression system, faults in test cases with faulty temperature sensors and plasmid instability of recombinant cells could be detected by the AANN. Since the raw data of measured variables included high-frequency noise, a wavelet filter bank (WFB) was applied to noise elimination before training of the AANN. The filtering performance of the WFB was compared with those of some classical first-order digital filters. The filtered signals at several resolution scales by the WFB were employed as the training data of the AANN. The computing time and summation of square of errors in training were compared, and the appropriate degree of the noise filtering and the density of the training data of the AANN were discussed. The performance of the feature capturing by the AANN was compared with that by a linear multivariate analysis, principal component analysis. A J index defined in this paper, using inputs and outputs of the AANN, was used for fault detection successfully. The output of the first unit of the trained AANN functioned effectively for the discrimination of the data in the abnormal cases from the data in the normal cases.

Early damage to lung tissue after irradiation detected by the magnetic resonance T2 relaxation time

We sought to determine whether nuclear magnetic resonance relaxation times of water in tissue would be useful to detect molecular damage in lung tissue within 2 weeks after irradiation. Tissue samples were obtained from the lungs of rats at various times between 1 and 14 days after exposure of a hemithorax to 20 Gy 60Co gamma irradiation. The spin-lattice relaxation time, T1, was measured by the inversion recovery method, and the spin-spin relaxation time, T2, was measured by both the Hahn spin-echo (Hahn T2) and the Carr-Purcell-Meiboom-Gill (CPMG T2) methods. The T2 of lung tissue could be divided into two components, T2 fast (T2f) and T2 slow (T2s), which reflected changes in the intracellular and extracellular water, respectively. The CPMG T2f increased significantly 3 days after irradiation (66.3 +/- 2.3 ms compared to 60.8 +/- 2.6 ms), and the CPMG T2s increased significantly 1 day after irradiation (155 +/- 11 ms compared to 138 +/- 7 ms), prior to the observation of abnormalities upon examination of the lung by light microscopy. The CPMG T2 values increased further up to 14 days after irradiation when significant increases were observed in values for T1, Hahn T2 and water content. Our results indicate that the molecular derangement in irradiated lung tissue was detected by the CPMG T2 measurement in the very early stage, and that MRI may be superior to conventional radiographs for detecting the early damage to lung tissue after irradiation.

Dependence of transverse relaxation time T2 of biologic tissues on the interpulse delay time in Carr-Purcell-Meiboom-Gill (CPMG) measurements

To determine the transverse relaxation time (T2) of biological tissues in nuclear magnetic resonance measurements, the Carr-Purcell-Meiboom-Gill (CPMG) method has been recommended to avoid the effect of external magnetic field inhomogeneity on T2 values. However, a dependence of T2 on the interpulse delay time (IPDT) in the CPMG measurements has been shown for biological tissues. The present study examined the dependence of the T2 on IPDT for muscle, lung (passively collapsed or degassed), and brain tissues. It was found that the CPMG T2 of the lung was strongly dependent upon the IPDT, in contrast to muscle and brain tissues. The IPDT dependence of the CPMG T2 for lung tissue, which was lessened by degassing, was affected by the magnetic field inhomogeneity due to air-tissue interfaces, but not by the spin-locking effect, since the T2 measured by the Carr-Purcell-Freeman-Hill (CPFH) method did not show this dependence. These results should aid in the evaluation of T2 values for biological tissues measured under various conditions and by different techniques.

Analysis of factors causing signal loss in the measurement of lung tissue water by nuclear magnetic resonance

The water content of lung, brain, and muscle tissue was measured by nuclear magnetic resonance (NMR) and compared with gravimetric determinations. The NMR signal intensity of water was measured by a single 90 degree pulse and by a spin-echo sequence. The absolute water content was determined by the difference in the sample's weight before and after desiccation. The NMR detectable water in each tissue was expressed as a percentage of the signal intensity for an equal weight of distilled water. Using the single pulse measurement, 67% of the gravimetrically-measured water was detected in collapsed lung samples (consisting of about 47% retained air), in contrast to 96% for brain and 98% for muscle. For degassed lung samples, the NMR detectability of water increased to 87% with the single pulse measurement and to 90% with the spin-echo measurement, but the values remained significantly less than those of brain or muscle. Factors that caused the NMR signal loss of 33% in collapsed lung samples were: air-tissue interfaces (20%), microscopic field inhomogeneity (3%), and a water component with an extremely short magnetization decay time constant (10%).

Expression of intercellular adhesion molecule-1 and lymphocyte function-associated antigen-1 on alveolar macrophages in the acute stage of radiation-induced lung injury in rats

We investigated the expression of intercellular adhesion molecule-1 (ICAM-1) and lymphocyte function-associated antigen-1 (LFA-1) on alveolar macrophages and on lung tissue in the early stage of radiation-induced lung injury. Cells in the bronchoalveolar lavage and lung tissue were obtained from rats at various times between 1 and 8 weeks after 20 Gy of 60Co gamma irradiation of a hemithorax. These specimens were stained immunohistochemically with anti-ICAM-1 and anti-LFA-1alpha monoclonal antibodies. The expression of these factors was compared with that of a control group. The total number of alveolar macrophages in the bronchoalveolar lavage was significantly reduced from 1 to 3 weeks, and the number of neutrophils was significantly increased 2 and 3 weeks after irradiation. ICAM-1 and LFA-1 expression on alveolar macrophages was significantly increased starting 1 week after irradiation. The expression of ICAM-1 and LFA-1 on lung tissue was not elevated up to 8 weeks after irradiation. In conclusion, the increased expression of ICAM-1 and LFA-1 on alveolar macrophages as early as 1 week after irradiation suggests that adhesion molecules play a role in the development of radiation-induced lung injury.

Nuclear magnetic resonance study of lung water compartments in the rat

Nuclear magnetic resonance transverse relaxation time (T2) was previously measured in studies of lung water. The T2 decay curves for peripheral lung tissue were found to be multiexponential with two T2 components: T2 fast (T2f) and T2 slow (T2s). This behavior was explained by the compartmentalization of water, in which the protons of water are restricted and do not undergo rapid exchange between the compartments. We investigated the origin of the water for these T2 components using excised rat lungs. The effect of magnetic field inhomogeneity due to air-tissue interfaces was examined by degassing some lungs. The contribution of intravascular water was examined by perfusing the lungs with oil or NaCl solutions. Degassing produced a greater increase in the T2f than the T2s component, indicating that the water in the alveolar walls exposed to air spaces contributed to the T2f. Perfusion with oil decreased the T2s, indicating that intravascular water contributed to the T2s component. The effects of intravascular osmotic pressure on the T2f and T2s components suggest that intracellular water is related to the T2f component.

[Clinicopathological study of pulmonary hamartoma with special reference to 6 patients who also had another tumor]

We studied 22 patients in whom intrapulmonary hamartoma was diagnosed between 1975 and 1994. Twelve were men and 10 were women, and their ages ranged from 20 to 72 years (averaged: 52.5). The sizes of the hamartomas ranged from 5 mm to 3 cm. Five patients also had other types of cancer (ling 3, colon 1, thyroid 1) and one had a mediastinal tumor (1). In those 6 patients, the hamartomas had to be distinguished from intrapulmonary metastasis. In 2 of those 6, thoracoscopic surgery was useful for obtaining sufficient materials for diagnosis. In one patient immunohistochemical analysis with anti-PCNA (proliferative cell nuclear antigen) antibody was useful in distinguishing leiomyomatous hamartoma from benign metastatic leiomyoma.

Estimation of the malignancy of pleural effusions by electron spin resonance

We conducted an electron spin resonance (ESR) study on human pleural effusions obtained from patients (n = 15) with and without cancer at 77 K. We detected two kinds of signals which are considered to be due to transition metal ions in metalloproteins such as Fe3+ in transferrin and Cu2+ in ceruloplasmin from their g values (g = 4.2 and 2.049) and line shapes. We found a significant difference in the signal intensity ratio, Cu2+/Fe3+, of the pleural effusions between cancer and noncancer patients by the Mann-Whitney U test (P < 0.01). The ESR study of pleural effusion enabled us to estimate its malignancy and may have future applications.

Magnetic resonance relaxation times in acute hydrostatic pulmonary edema induced by noradrenaline in rats

Models of pulmonary edema have been used to study the nuclear magnetic resonance (NMR) characteristics of lung water. Several investigators have measured changes in the relaxation times in the permeability type of pulmonary edema, but relatively few have measured relaxation times in the hydrostatic type of pulmonary edema. In this study we determined the characteristics of NMR relaxation times T1, T2 (Hahn spin-echo decay) and water content in acute hydrostatic pulmonary edema induced by noradrenaline administration in rats. Changes in T1 and T2 showed a significant prolongation in hydrostatic pulmonary edema. T2 decay curves for peripheral lung tissues were multiexponential and fit two components [T2 fast (T2f) and T2 slow (T2s)]. With two-component T2 analysis, T2s showed greater prolongation than did T2f. The increase in T2s was significantly correlated with an increase in water content, but the increase in the T2f value was not correlated with water content or with a change in T2s. The T2s component, which likely reflected changes in interstitial water, was more closely related than the T2f component to an increase in water content in hydrostatic pulmonary edema. Results suggested that regional changes in hydrostatic pulmonary edema may be evaluated by multicomponent T2 analysis.

[Suppression by methylprednisolone of the expression of LFA-1 by alveolar macrophages in irradiated rat lungs]

A common side effect of radiotherapy is the development of fibrosis in the irradiated tissue. To study the effects of methylprednisolone on acute radiation-induced lung injury, we counted neutrophils, lymphocytes, and macrophages, and measured the expression on alveolar macrophages of lymphocyte function associated molecule-1 (LFA-1) in bronchoalveolar lavage fluid recovered from irradiated rat lungs. Twenty 10-week-old male Wistar rats were divided into 4 groups of 5 rats each: (1) a radiation group (R), which received 20 Gy of radiation from 60Co to the left hemithorax in one fraction; (/) a methylprednisolone treatment group (RS), which received the same dose of radiation as the R group, along with 2.0 mg x kg-1 of methylprednisolone (6 alpha methylprednisolone 21-acetate) by intramuscular injection 6 hours before and every 48 hours after irradiation; (3) an untreated control group (C); and (4) a methylprednisolone control group (S), which received the same dosage of methylprednisolone as the RS group. Rats were kept under specific-pathogen-free conditions. Bronchoalveolar lavage of the left lung was done in all 4 groups 2 week after irradiation. The number of neutrophils in the recovered fluid was significantly higher in the R and RS groups than in the C and S groups. The expression of LFA-1 on alveolar macrophages was significantly higher in the R group than in the RS, C, and S groups. The number of neutrophils in bronchoalveolar lavage fluid and the expression of LFA-1 on alveolar macrophages were significantly higher in the R group than in the RS groups. These results suggest that the increase in the expression of LFA-1 on alveolar macrophages and the increase in the number of neutrophils in bronchoalveolar lavage fluid are related to acute radiation-induced lung injury. Methylprednisolone suppressed the expression of LFA-1 on alveolar macrophages and the increase in the number of neutrophils measured in bronchoalveolar lavage fluid 2 weeks after irradiation.

Comparison of calculated and experimental NMR spectral broadening for lung tissue

NMR lineshapes were calculated for a model of lung, and NMR proton spectra were measured for individual voxels in an excised inflated rat lung. NMR lines for parenchymal lung regions containing alveoli, alveolar ducts, and capillaries were calculated using a computer simulation of the NMR signal from a three-dimensional honeycomb-like structure, a collection of modified Wigner-Seitz cells. These cells were modified by rounding the corners and increasing the thickness of the boundaries to model various degrees of lung inflation and lung water. NMR lineshapes were also calculated for the central or nonparenchymal lung regions containing bronchi and large blood vessels. A comparison of theoretical lineshapes with those measured in individual voxels both in the parenchymal and in the central (largely nonparenchymal) regions in excised rat lungs at an inflation pressure of 30 cm of water shows excellent agreement. These results indicate that the NMR lineshape reflects the underlying lung geometry. This research constitutes the first calculations and measurements of NMR lineshapes in lung. The appendix describes a new method for calculating the magnetic field inside a weakly diamagnetic material of arbitrary shape placed in an otherwise uniform external magnetic field. This new method does not require either solution of simultaneous equations or evaluation of integral expressions.

MR appearance of pulmonary metastatic calcification

We report a case of metastatic pulmonary calcification that showed hyperintense signal on T1-weighted MRI. This uncommon MR appearance of calcification is similar to the MR characteristics of calcification in the brain due to abnormal calcium metabolism.

Comparison of carboplatin/etoposide/vincristine with cisplatin/etoposide as combination chemotherapy for small cell lung cancer

We compared the efficacy and toxicity of the CEV regimen (carboplatin at 300 mg/m2 on day 1, etoposide at 100 mg/body on days 1 to 3, and vincristine at 1 mg/m2 on days 1 and 8) with the PVP regimen (cisplatin at 80 mg/m2 on day 1 and etoposide at 100 mg/body on days 1 to 3) in patients with untreated small cell lung cancer (SCLC). Of the 13 patients treated with the PVP regimen, two achieved complete response (CR, 15.4%) and eight partial response (RP, 61.5%). Of the 15 evaluable patients treated with the CEV regimen, one achieved CR (6.7%) and 13 PR (86.7%). Thus, there was no significant difference in response rate between the PVP (76.9%) and CEV (93.3%) regimens. There was also no significant difference in response duration [PVP, 756 +/- 903 (mean +/- SD) days vs. CEV, 318 +/- 159 days] and median survival time (PVP, 472 days, vs. CEV, 471 days). The number of days hospitalized divided by the duration of chemotherapy was shorter with the CEV regimen, but this difference was not statistically significant. Severe leukopenia (< 2,000/microliter) occurred in 15.4% of PVP patients and 31.3% of CEV patients. Severe thrombocytopenia (< 50,000/microliter) occurred in only one patient in this study. In conclusion, the CEV regimen demonstrated a response rate and median survival time comparable to the PVP regimen, although the response time was short. The CEV regimen had the advantage of lower toxicity and ease of outpatient administration. Thus, the CEV regimen is a useful outpatient induction chemotherapy for SCLC.

Optimization of rice alpha-amylase production using temperature-sensitive mutants of Saccharomyces cerevisiae for the PHO regulatory system

A typical example of rational system synthesis for bioproduction by the cultivation of microorganisms harboring a recombinant plasmid was studied. First, two temperature-controllable expression systems for a foreign gene in Saccharomyces cerevisiae were constructed. The promoter of the PHO84 gene, which encodes an inorganic phosphate (Pi) transporter of S. cerevisiae and is controlled by Pi concentration through the PHO regulatory system, was used. And two temperature-sensitive mutants of S. cerevisiae for the PHO regulatory system were used as the host with rice alpha-amylase expression vector. One was temperature-sensitive pho81 mutant, SH3337, and the other was temperature-sensitive pho80 mutant, YKU107. When the strain SH3337 is cultivated at a lower temperature, the rice alpha-amylase gene connected downstream of the PHO84 promoter is expressed, but at a higher temperature, it is not. Conversely, with the strain YKU107, the transcription of the rice alpha-amylase gene is induced at a higher temperature and repressed at a lower one. The optimal cultivation temperature strategies for maximum production of rice alpha-amylase in batch cultures of these two recombinant strains were then determined by the Maximum Principle using the relationships of the specific growth and specific production rates to the cultivation temperature. The optimal strategies were easy to realize and were shown to be effective for maximum product. Finally, under these maximum alpha-amylase production strategies, the alpha-amylase activities and alpha-amylase yields in terms of glucose consumption for these recombinant strains were calculated on the basis of experimental data and compared for various operation times. The study demonstrates how a foreign gene expression system can be synthesized using a temperature-sensitive mutant with a given objective and under given constraints.

[Histological evaluation of lung cancer with T2-weighted magnetic resonance images]

We investigated the differences in signal intensity of lung cancer tissue and non-cancerous lung tissues on T2-weighted magnetic resonance (MR) images. MR images were obtained from patients with squamous cell carcinoma (n = 6), adenocarcinoma (n = 5), small cell carcinoma (n = 5), and large cell carcinoma (n = 1). To compare the MR signal intensity between tissues, we calculated the signal intensity ratios for tumor/skeletal muscle and lung/skeletal muscle. The MR signal intensity for each tissue was measured with a densitometer and T2-weighted MR images with a similar window and a center. The value of the signal intensity ratio for squamous cell carcinoma (3.26 +/- 0.76) was greater than those for adenocarcinoma (1.99 +/- 0.50, p < 0.05), small cell carcinoma (2.35 +/- 0.60), large cell carcinoma (2.46), and non-cancerous lung tissues (1.70 +/- 0.68, p < 0.02). The values of the MR signal intensity ratio for non-cancerous lung tissues were 2.00 for a collapsed lung, 0.93 for a firotic lung, and 2.18 for a fibrotic lung with obstructive pneumonia. The results suggest that the MR signal intensity ratio for pathologic tissues/normal skeletal muscle can be a useful indicator for qualitative and quantitative MR imaging diagnosis.

Muscle energy metabolism and nutritional status in patients with chronic obstructive pulmonary disease. A 31P magnetic resonance study

We investigated the relationship between nutritional status and muscle energy metabolism during exercise in 18 male patients with chronic obstructive pulmonary disease (COPD) and 15 male control subjects using 31P nuclear magnetic resonance spectroscopy (31P-MRS). The patients and control subjects were further categorized as in either a well-nourished (% ideal body weight, % IBW > or = 90) or malnourished (% IBW < 90) state. Muscle energy metabolism was evaluated by determining the ratios PCr/(PCr + Pi) (PCr, phosphocreatine; Pi, inorganic phosphate), and ATP/(PCr + Pi + ATP). The exercise consisted of repetitive hand grips performed against a load. The work rate was normalized for the individual's lean muscle mass by dividing work performed by the forearm fat-free cross-sectional area, which was calculated using 1H-MRS. The PCr/(PCr + Pi) values during exercise did not correlate with the % IBW in any of the groups of control subjects or COPD patients. Furthermore, the PCr/(PCr + Pi) did not correlate with the normalized work rate in either the well-nourished or malnourished subject groups. However, there were correlations within the groups of control subjects and COPD patients. The PCr/(PCr + Pi) values for the normalized work rate were consistently lower in the COPD patients than in the control subjects. These findings suggest that the altered muscle metabolism in COPD patients is not affected by their nutritional status.

[Nuclear magnetic resonance relaxation times for human lung cancer and lung tissues]

We investigated the nuclear magnetic resonance (NMR) relaxation times, T1 and T2, for lung cancer tissue, and other samples of lung tissue obtained from surgical specimens. The samples were nine squamous cell carcinoma, five necrotic squamous cell carcinoma, 15 adenocarcinoma, two benign mesothelioma, and 13 fibrotic lungs. The relaxation times were measured with a 90 MHz NMR spectrometer and the results were correlated with histological changes. The values of T1 and T2 for squamous cell carcinoma and mesothelioma were significantly longer than those of adenocarcinoma and fibrotic lung tissue. There were no significant differences in values of T1 and T2 between adenocarcinoma and lung tissue. The values of T1 and T2 for benign mesothelioma were similar to those of squamous cell carcinoma, which suggested that increases in T1 and T2 are not specific to malignant tissues.

In vivo effect of methylprednisolone on lipopolysaccharide-induced superoxide production by pulmonary and circulating blood neutrophils in rats

The effect of methylprednisolone on superoxide production by pulmonary and circulating blood neutrophils was investigated in rats after the intravenous injection of lipopolysaccharide. Superoxide production by both types of neutrophils was increased by lipopolysaccharide injection, and pretreatment with methylprednisolone inhibited this increase. The inhibitory effect of methylprednisolone on pulmonary neutrophils was greater than that on circulating blood neutrophils. Methylprednisolone also prevented the increase in pulmonary vascular permeability induced by lipopolysaccharide, but failed to inhibit intrapulmonary neutrophil accumulation. These results suggest that the suppression of superoxide production may be one mechanism by which methylprednisolone prevents endotoxin-induced lung damage.

Roles of bladder distension, urinary pH and urinary sodium ion concentration in cell proliferation of urinary bladder epithelium in rats ingesting sodium salts

The relative importance of bladder distension, urinary pH and sodium ion concentration for cell proliferation in the bladder epithelium of rats fed various sodium salts was investigated. When a diet containing 5% NaHCO3 was fed to male rats, the bladder epithelium showed an increase in replicating cells, together with distension, increased urine pH and high urine sodium ion concentration. Cell proliferation also occurred when bladders were subjected to distension in vivo by mechanical (female) or physiological (male) means. Inclusion of CaCO3 in the diet produced high urinary pH without alteration in the other factors and did not induce cell proliferation. Increased proliferation occurred when CaCO3 was combined with these mechanical or physiological treatments. Thus, high urinary pH was of secondary importance to bladder distension as a causative factor, but acted to enhance cell proliferation when distension occurred. Similar findings were obtained with regard to sodium ion concentration. In conclusion, this study demonstrated that bladder distension is one of the prerequisites for promoter-induced cell proliferation in the bladder epithelium, with high urinary pH and sodium ion concentration.

Tissue characterization of pneumonia and irradiated rat lungs with magnetic resonance relaxation times

To interpret the MRI signal intensities, the T1 and T2 values were determined in vitro for rat lungs with radiation pneumonitis, fibrosis or pneumonia, and also for muscle and fat tissues. The transverse magnetization decays mentioned above exhibited two components, a T2 fast (T2f) and a T2 slow (T2s) component. Lungs from rats with pneumonia had significantly longer T2f and T2s values than lungs from rats with radiation pneumonitis and fibrosis. The T2f and T2s values for a "pneumonia lung" were not significantly different from those of muscle. The measured values of T2f and T2s suggested that radiation pneumonitis and fibrosis likely exhibit lower signal intensities than do muscle and that a "pneumonia lung" likely exhibits a similar signal intensity to that of muscle on T2-weighted MR images.