Right ventricle of patients undergoing congenital cardiac surgery differentially expresses haem oxygenase-1 and heat shock protein 70 genes.

Reactive oxygen species are implicated in the pathogenesis of cardiac hypertrophy. Haem oxygenase-1 (HO-1), the rate-limiting enzyme in haem catabolism, is induced by oxidative stress and confers protection against oxidative tissue injuries. We used Northern blotting to examine expression of HO-1 and heat shock protein 70 (HSP70) in the hypertrophic cardiac muscle of eight patients (one infant and seven children) who underwent surgery for congenital heart disease. Levels of HO-1 and HSP70 mRNA were significantly increased in all specimens, but the orders of magnitude of the increases were different, suggesting that the genes expressing HO-1 and HSP70 are regulated separately.

Microbial production of poly-D-3-hydroxybutyrate from CO2.

This short review covers the biotechnological aspects of the production of poly-D-3-hydroxybutyric acid, P(3HB), from H2, O2 and CO2 by autotrophic culture of the hydrogen-oxidizing bacterium, Ralstonia eutropha. Considering the efficiency of utilization of a gas mixture as substrate, a practical fermentation process using R. eutropha for the mass production of P(3HB) from CO2 should be designed on the basis of a recycled-gas, closed-circuit culture system. Also, maintaining the O2 concentration in a gas phase lower than 6.9% (v/v) is essential to prevent the gas mixture from exploding. Our study, using an explosion-proof fermentation bench plant and a two-stage culture system with a newly designed air-lift fermenter, demonstrated that very high P(3HB) yield and productivity could be obtained while the O2 concentration was maintained below 6.9%. However, a study on the continuous production of P(3HB) from CO2 by chemostat culture of R. eutropha revealed that the productivity and content of P(3HB) in the cells was considerably lower than by fed-batch culture. It is deduced that the use of the hydrogen-oxidizing bacterium, Alcaligenes latus, which accumulates P(3HB) even in the exponential growth phase, will be useful for the effective production of P(3HB) from CO2.

[A case of central retinal artery occlusion after anterior posterior fusion of the lumbar spine].

We report a case of central retinal artery occlusion after anterior-posterior fusion of the lumbar spine. The patient suddenly lost his vision of the right eye in the ICU just after the end of long procedure for anterior-posterior fusion of the lumbar spine. The patient was diagnosed as having central retinal artery occlusion, and treated successfully with treatments including immediate administration of urokinase and PGE1, stellate ganglion block, and hyperbaric oxygen therapy. The patient was discharged from the hospital on the 54th postoperative day with adequate vision to drive a car. Central retinal artery occlusion is a rare but very serious complication during and after supine surgery with prone position. It is very important for us to be aware of its possible occurrence. We have to diagnose and treat, as soon as possible, the vision loss after the spine surgery.

Significance of adrenomedullin under cardiopulmonary bypass in children during surgery for congenital heart disease.

To elucidate the effect of adrenomedullin (AM) on fluid homeostasis under cardiopulmonary bypass (CPB), we investigated the serial changes in plasma AM and other parameters related to fluid homeostasis in 13 children (average age, 28.2 months) with congenital heart disease during cardiac surgery under CPB. Arterial blood and urine samples were collected just after initiation of anesthesia, just before commencement of CPB, 10 min before the end of CPB, 60 min after CPB, and 24 h after operation. Plasma AM levels increased significantly 10 min before the end of CPB and decreased 24 h after operation. Urine volume increased transiently during CPB, which paralleled changes in AM. Simple regression analysis showed that plasma AM level correlated significantly with urinary vasopressin, urine volume, urinary sodium excretion, and plasma osmolarity. Stepwise regression analysis indicated that urine volume was the most significant determinant of plasma AM levels. Percent rise in AM during CPB relative to control period correlated with that of plasma brain natriuretic peptide (r = 0.57, P < 0.01). Our results suggest that AM plays an important role in fluid homeostasis under CPB in cooperation with other hormones involved in fluid homeostasis.

Induction of renal metallothionein in rats with ischemic renal failure.

Metallothionein (MT) is induced by various types of oxidative stress. However, whether or not MT is induced in renal ischemia/reperfusion injury, in which oxidative stress is believed to play a major role, remains unknown. The present study investigated MT expression in the kidneys of rats with ischmic acute renal failure (IARF). Rats were subjected to 60 min of bilateral renal ischemia followed by reperfusion. Renal MT mRNA expression was then analyzed by Northern blotting. MT expression in ischemic kidney was also localized by in situ hybridization and immunohistochemistry. Renal MT mRNA expression, which was barely detectable in the sham-operated control kidney, increased significantly at 3 h afer reperfsion, continued to increase to a maximal level at 24 h that was maintained for 48 h. The level of MT mRNA expression returned to that of the control by day 4. A morphological study revealed that MT was expressed exclusively in the renal tubular epithelial cells, which are the targets of ischemia/reperfusion injury, and that MT predominated in the outer medulla in the IARF rat kidney at transcriptional and translational levels. These results suggest that MT induced in the IARF rat kidney plays an important role in protecting renal cells against oxidative stress induced by ischemia/reperfusion.

[Four cases of the anomalous origin of the left coronary artery from the pulmonary artery].

We report perioperative management of 4 patients with anomalous origin of the left coronary artery from the pulmonary artery. This report involves with 3 infant cases and an adult. Two infants underwent coronary reimplantation procedure and Takeuchi's method was performed on the other infant. In all infant cases, mitral valve plasty was performed to correct mitral regurgitation secondary to papillary muscle dysfunction. The adult patient underwent CABG with ligation of LCA. General anesthesia was performed with high doses of fentanyl in all cases. We employed a relatively high PaCO2 and low FIO2 in order to maintain a high pulmonary vascular resistance. It aims to decrease the incidence of left to right shunt. We used epinephrine to wean one infant and the adult from cardiopulmonary bypass. Perioperative course was uneventful with the use of catecholamines and high doses of vasodilators for left ventricular dysfunction and coronary perfusion under mechanical ventilation.

[Anesthetic and perioperative management of 1000 cases of congenital heart surgery--massive vasodilator therapy and early extubation].

We report our anesthetic and perioperative management of 1000 cases of congenital heart surgery in Okayama University Medical School over the last six and a half years. Most of these patients were anesthetized by fentanyl and all patients were managed in our ICU postoperatively. Although hospital death rate in all patients was 4.5%, almost half of dead patients were patients with hypoplastic left heart syndrome. Neonatal mortality rate has been still high, 18.9%, which has been our main problem. We tried to extubate patients with complex congenital heart diseases earlier postoperatively for the last three years, using massive dose of vasodilators without nitric oxide.

Effects of rheological change by addition of carboxymethylcellulose in culture media of an air-lift fermentor on poly-D-3-hydroxybutyric acid productivity in autotrophic culture of hydrogen-oxidizing bacterium, Alcaligenes eutrophus.

The effects of rheological change by addition of sodium carboxymethylcellulose (CMC) to culture medium in an air-lift-type fermentor on autotrophic production of poly-(D-3-hydroxybutyric acid) [P(3HB)] by two-stage culture of Alcaligenes eutrophus is investigated. Addition of 0.05% CMC increased P(3HB) production rate during the P(3HB) accumulation phase to twice that of the control culture. It was thought that addition of a small amount of CMC was beneficial for production of P(3HB) employing the air-lift fermentor under safe autotrophic culture conditions in wich oxygen concentration was maintained below 6.9% (v/v). the volumetric mass transfer coefficient (K(L)a) observed in the presence of CMC is shown to correlated with the P(3HB) production rate obtained. (c) 1997 John Wiley & Sons, Inc. Biotechnol Bioeng 53: 529-533, 1997.

Bacterial endotoxin-induced expression of metallothionein genes in rat brain, as revealed by in situ hybridization.

In order to clarify acute-phase response in brain, we investigated induction of metallothionein (MT) genes by administrating an endotoxin (lipopolysaccharide) in rat intraperitoneum. We performed in situ hybridization on the serial brain sections to identify the cells expressing the MT genes in acute-phase. After endotoxin administration, transcripts of MT genes were detected in the arachnoideal, ependymal cells and glial cells around the Purkinje cells of the cerebellum, while no significant induction of the MT genes by zinc ion was observed in brain. These results suggest that the acute-phase response occurs specifically in at least these 3 non-neuronal cells.

[Usefulness of midazolam in a modified NLA--study on plasma concentrations].

Midazolam 0.2mg.kg-1 or diazepam 0.2mg.kg-1 was used as an induction agent in a modified NLA. Plasma concentrations of midazolam or diazepam were measured with benzodiazepines screen method, which was based on enzyme immunoassay. Pharmacokinetic analysis is based on the plasma concentration-time courses after a bolus injection. The distribution half-life (T alpha 1/2) of midazolam, 1.24 minutes, was shorter than that of diazepam, 3.85 minutes. The elimination half-life (T beta 1/2) of midazolam, 5.44 hours, was similar to that of diazepam, 5.02 hours. The initial fall-off in the alpha-phase was due to the distribution of the drug from plasma to the peripheral compartment, while the drop in the beta-phase was caused by redistribution from the peripheral compartment and total elimination of the drug. Midazolam was thought to be useful as an induction agent in a modified NLA, because midazolam is distributed to the peripheral compartment faster than diazepam. As midazolam has a long elimination half-life as that of diazepam, prolongation of its effects has to be considered when a large dose or continuous infusion is employed.

Correlation of direct viable counts with heterotrophic activity for marine bacteria.

Viable-bacteria counts, heterotrophic activity, and substrate responsiveness of viable bacteria have been used to measure microbial activity. However, the relationship between these parameters is not clear. Thus, the direct viable count (DVC) method was used to analyze seawater samples collected from several different geographical locations. Samples collected from offshore waters of the South China Sea and western Pacific Ocean yielded DVC that indicated the presence of surface and subsurface peaks of viable, substrate-responsive bacteria which could be correlated with turnover rates of amino acids obtained by using uniformly C-labeled amino acids. DVC were always less than total viable counts (acridine orange direct counts), and the DVC subsurface peak occurred close to and within the chlorophyll a zone, suggesting algal-bacterial interactions within the layer. For comparison with the open-ocean samples, selected substrates were used to determine the response of viable bacteria present in seawater samples collected near an ocean outfall of the Barceloneta Regional Waste Treatment Plant, Barceloneta, Puerto Rico. The number of specific substrate-responsive bacteria at the outfall stations varied depending on the substrate used and the sampling location. Changes in the population size or physiological condition of the bacteria were detected and found to be associated with the presence of pharmaceutical waste.

3-Amino-3-deoxy-D-glucose: an antibiotic produced by a deep-sea bacterium.

Gram-positive bacteria isolated from deep-sea sediments of the Pacific basin showed considerable antibacterial activity. A Bacillus strain, isolated from a sediment sample collected at a depth of 4310 m, was shown to produce 3-amino-3-deoxy-D-glucose, a known antibiotic.

Purification and some properties of halophilic protease produced by a moderately halophilic marine Pseudomonas sp.

Halophilic protease in culture fluids of a moderately halophilic marine Pseudomonas sp. (A-14) was purified by ammonium sulfate precipitation, DEAE-cellulose chromatography, and gel filtration through Sephadex G-200. The enzyme was purified to homogeneity, as judged by polyacrylamide gel electrophoresis. The molecular weight of the enzyme was estimated to be 120 000. The optimum pH for activity was 8.0. The enzyme had maximal activity at 18% NaCl concentration. The enzyme was activated by Mg2+, Co2+, and Ca2+. Ca2+ increased the heat stability, and heavy metal ions such as Fe2+, Cu2+, and Hg2+ inactivated the enzyme. Thiol reagents and diisopropyl fluorophosphate did not affect the enzymatic activity of the protease. Metal-complexing reagents, such as ethylenediaminetetraacetic acid and o-phenanthroline, inhibited enzymatic activity, although citrate and oxalate did not affect it.

Uptake of D-glucose and L-proline by oligotrophic and heterotrophic marine bacteria.

The transport systems of the oligotrophic bacterium 486 for D-glucose and L-proline have been compared with those of the heterotrophic bacterium RP-303. Kinetic studies demonstrated that the rates of D-glucose and L-proline uptake by the two organisms were saturable processes. The apparent Km values of strain 486 for D-glucose and L-proline were 13.0 microM and 0.2 microM, respectively, whereas those of strain RP-303 were 3.2 microM for D-glucose and 1.8 microM for L-proline. Competition studies indicated that the D-glucose transport system of each bacterium was highly specific for D-glucose. The L-proline transport system of the oligotrophic bacterium 486 had a broad specificity, whereas that of the heterotrophic bacterium RP-303 had a narrow one.

Distribution of viable marine bacteria in neritic seawater around Japan.

The direct viable court (DVC) method of determining the number of living bacteria in natural seawater was applied to samples collected from areas around Japan ranging from polluted to oligotrophic. In summer, the DVC comprised 1.5-39.8% (mean, 11.2%) of the total direct count (TDC) in Tokyo Bay, which was highly eutrophic. In offshore areas (Sagami Bay and the Kuroshio region), the percentages ranged from 0.7 to 7.9 (mean 2.8%). In winter, slightly higher percentages were observed in Sagami Bay. The majority of DVC cells were free-living. The distruction of bacteria correlated closely with particulate or dissolved organic matter.

Distribution of aerobic bacteria which contain bacteriochlorophyll a.

Sixteen strains of aerobic bacteria which contain bacteriochlorophyll a were isolated from the samples collected in aerobic marine environments: thalli of Enteromorpha linza, Porphyra sp., Sargussum horneri; beach sand; and the surface seawater from Aburatsubo Inlet. When they occurred, their proportions among the aerobic heterotrophic populations ranged from 0.9 to 1.1% in the seaweed samples and from 1.2 to 6.3% in the beach sand samples and were 0.9% in the seawater sample. The results suggested that the aerobic photopigmented bacteria widely inhabit aerobic marine environments.

Comparative study of the aerobic, heterotrophic bacterial flora of Chesapeake Bay and Tokyo Bay.

A comparative study of the bacterial flora of the water of Chesapeake Bay and Tokyo Bay was undertaken to assess similarities and differences between the autochthonous flora of the two geographical sites and to test the hypothesis that, given similarities in environmental parameters, similar bacterial populations will be found, despite extreme geographic distance between locations. A total of 195 aerobic, heterotrophic bacterial strains isolated from Chesapeake Bay and Tokyo Bay water were examined for 115 biochemical, cultural, morphological, nutritional, and physiological characters. The data were analyzed by the methods of numerical taxonomy. From sorted similarity matrices, 77% of the isolates could be grouped into 30 phena and presumptively identified as Acinetobacter-Moraxella, Caulobacter, coryneforms, Pseudomonas, and Vibrio spp. Vibrio and Acinetobacter species were found to be common in the estuarine waters of Chesapeake Bay, whereas Acinetobacter-Moraxella and Caulobacter predominated in Tokyo Bay waters, at the sites sampled in the study.