Studies on in vitro paraquat and diquat removal by activated carbon

The adsorption characteristics of paraquat and diquat onto activated carbon in vitro were discussed for the primary treatment of acute poisoning by accidental, suicidal or homicidal ingestion of paraquat containing herbicides. Paraquat was adsorbed onto activated carbon more abundantly and more rapidly in physiological saline solution than that in artificial gastric juice and distilled water. Most suitable solvent for paraquat removal by activated carbon was physiological saline solution (0.9% sodium chloride solution). No significant correlation was observed between the ability of paraquat removal and the properties of adsorbent. Paraquat was preferentially adsorbed onto activated carbon in the mixed solution. The adsorption abilities by activated carbon (the removal ratio, the amount adsorbed and the adsorption rate) for paraquat were larger than those for diquat, and it was enhanced by added sodium chloride and added magnesium sulfate. Enhancing effect for adsorption removal was proportional to the saline concentration. As addition of salts into carbon suspension enhanced the adsorption ability, it will contribute to the effective treatment of acute poisoning.

Evaluation of the effects of various factors on the serum triglyceride level in young adults

The life style of young adults has been receiving attention with a view to its improvement to preventing coronary heart diseases (CHD) in later life. In this study, for determining the influence of different life styles on the serum triglyceride level, we carried out surveys and laboratory studies on the relationships of the nutritional intake, physical activity, and cigarette smoking and alcohol consumption of young adults with their serum triglyceride levels. The nutritional survey indicated a significant correlation between the serum triglyceride level and carbohydrate intake (p < 0.01). In the survey of physical activity, a significant inverse correlation was found between the energy expenditure per kg body weight and the serum triglyceride level (p < 0.05). No significant relationship was found of smoking or drinking with the serum triglyceride level. The body mass index was found to have effects on both the serum triglyceride and total cholesterol levels. Of the factors examined, carbohydrate intake and energy expenditure per kg body weight had the greatest effects on the serum triglyceride level. Considering the trend for young people to consume large quantities of carbonated drinks, in which most of carbohydrate is sucrose, we tested the affect of a high carbohydrate diet on one group of subjects and found that it caused a significant increase in the serum triglyceride level (p < 0.05). Another group for whom a mild exercise regimen was prescribed showed slight, but not significant decrease in the serum triglyceride level. These results suggest that at least optimal nutrition and physical activity including weight control during adolescence are important for preventing CHD.

The survival of rat cerebral cortical neurons in the presence of trophic APP peptides

One function of Alzheimer amyloid protein precursor (APP) is the regulation of growth and differentiation in several types of cells, including fibroblasts, PC12 cells, and neurons. This activity is represented by a small stretch of amino acids in the center of the molecule around RERMS. The APP 17-mer peptide containing the RERMS domain supported survival and neurite extension of rat cortical neurons in a dose-dependent and sequence-specific manner. The APP fragment synthesized in Escherichia coli supported the survival and neurite extension of rat cortical neurons, whereas the mutant APP fragment lacking the 30 amino acids around the RERMS domain had drastically reduced activity to support the survival and neurite extension. The current study established APP as a neuron survival factor and determined that the sequence around RERMS is important for this function.

[Tumor blood flow measured by dynamic CT]

A method of measuring tumor blood flow by dynamic CT (DCT) was devised, and the reliability of data obtained by the new method was investigated. The subjects were 16 patients with superficial tumors who underwent measurement of tumor blood flow by both the new DCT-based method and 15O gas positron emission tomography (PET). The results showed that tumor blood flow as measured by the new DCT-based method was about 1.2 times greater than that measured by PET, and both data yielded a straight line passing almost through the origin (proportional relationships); the correlation coefficient was 0.836. On the basis of these studies, it was concluded that the newly devised DCT-based method yields reliable data in the measurement of tumor blood flow.

Evaluation of serum lactate dehydrogenase activity for estimation of energy expenditure in human subjects

We investigated the relationship between serum lactate dehydrogenase (LDH) activity and energy expenditure in young adults, evaluating their serum LDH activities in order to develop an index of energy expenditure. The results obtained were as follows. (1) There were significant correlations between the serum LDH activity and energy expenditure/day, energy expenditure/body weight/day and daily activity index in men. (2) There were significant correlations between the serum LDH activity and energy expenditure/day and daily activity index in women. (3) A group of men who 'rarely' exercised had lower levels of serum LDH activity than those who exercised 'sometimes' or 'usually', but little difference was noted between similar groups of women.

Assessment of the mechanical properties of peripheral arteries in chain saw operators using a photosensor

In order to evaluate the severity of peripheral vascular disorders, and to detect changes in the digital arteries of workers who use chain saws, the mechanical properties of the digital arteries of 22 such workers were examined using a photosensor. The elastic properties and the nonlinearity of digital arteries were assessed through observation of the changes in the vascular volume ratio (V/Vo) against the volume (Vo) at mean blood pressure (Pm). A significant negative correlation was found between age and V/Vo at a transmural pressure of 30 mmHg (V30/Vo), which suggested that V30/Vo tended to decrease with aging. Although it was impossible to calculate V30/Vo for chain saw operators because of the vague changes in the volume pulse wave, this nonlinearity was more clearly observed through changes in the relative vascular volume (V/V40) along with a reduction in cuff pressure (Pc) to 40 mmHg below systolic blood pressure. A group of similarly aged healthy controls and three groups of workers with a different severity of vibration-induced white finger (VWF), i.e., no symptoms of VWF, mild VWF and severe VWF, were classified according to the changes in their V/V40 and the reduction in Pc. The results obtained in the present study suggest that the peripheral vascular disorders in workers using chain saws are due to the opening disturbance of the arteries with nonlinear changes in the peripheral artery, which is related to functional and organic abnormality of the arteries.

A carcinoma in situ arising in an endocervical polyp--a case report

A rare case of a carcinoma in situ arising from an endocervical polyp is described. The covering epithelium of the polyp transformed gradually into a carcinoma in situ via squamous metaplasia and dysplasia, spreading horizontally with glandular involvement, and colliding with the surface columnar cells. The lack of tumor tissue in the pedicle and adjacent cervical region confirms the case was a carcinoma in situ originating from the surface epithelium of the endocervical polyp.

Study on hydrophilic properties of gelatin as a clinical wound dressing. I. Hydrophilic properties of gelatin as a wound dressing

A basic study on hydrophilicity of gelatin was made of the fitness, water-absorbing ability, water-holding ability, affinity and stability of included water in order to utilize it as a protective covering for medical use. Gelatin No. 3, being highly viscous and having a lower jelly strength, was strongly viscous and flexible, and thus, it stuck close to the surface of a lesioned site such as a wound or a burn. Since the melting point of a gelatin containing 50% water was in the range of 43 to 45 degrees C, the gelatin will be fully used as a protective covering for a wound. Below 20% relative humidity, water molecules were bound to the polar amino acid side chains of gelatin and the bound water caused a swelling of the gelatin, which is maintained by capillary sorption of water into its collagen-like four-dimensional structure. The amount of water sorbed at a relative humidity of 80% at 11 degrees C was higher by 50 to 80 mg/g compared to that at 37 degrees C. Gelatin No. 3 had a very high water-holding ability and it was very hard for it to release the sorbed water at a relative humidity of 80 to 90%. Water molecules were bound to the strong active sites of the gelatin at low relative humidity. The gelatin swelled and then, newly active sites appeared on the surface of the gelatin. The hydrophilic activity decreased with an increase in moisture content, whereas the stability of water molecules in the gelatin increased.(ABSTRACT TRUNCATED AT 250 WORDS)

Incidence of anemia in women in fishing villages

Studies were made on the incidence of anemia among women in fishing villages in Tokushima prefecture. In 839 women in the fishing villages, the mean values for hemoglobin (Hb) and the hematocrit (Ht) were 12.5 +/- 1.3 g/dl and 37.9 +/- 3.3%, respectively, and the incidence of anemia was 20.1%. The incidence of anemia was high in elderly women. In 158 women in the fishing villages, the mean serum level of iron was 80.0 +/- 41.6 micrograms/dl and the incidences of iron deficiency anemia in the women with serum iron levels of under 50 and 70 micrograms/dl were as high as 25.9 and 41.1%, respectively. Almost all women with Hb values of under 11.0 g/dl had iron-deficiency anemia. The mean values for the total iron binding capacity (TIBC), unsaturated iron binding capacity (UIBC) and percentage iron saturation, were 365.6 +/- 65.1, 286.3 +/- 92.8 micrograms/dl and 23.3 +/- 13.0%, respectively. The incidence of anemia was 40.0% in the women with percentage iron saturation value of under 20%.

Study on hydrophilic properties of gelatin as a clinical wound dressing. II. Water-absorbing property and hemostatic effect of gelatin

For clinical use of gelatin as a dressing, we determined the water-absorbing capacity of gelatin for isotonic sodium chloride solution (ISCS) and bovine serum albumin-isotonic sodium chloride solution (BSA-ISCS). There was no significant difference between water absorption of gelatin with ISCS and with BSA-ISCS. The water-absorbing capacity of gelatin increased with increasing viscosity: gelatins No. 1 > No. 2 > No. 3. Enormous spaces of 20 to 30 microns or approximately 10 microns in size were observed on the gelatin surface. Scaly materials of 10 to 20 microns in size were also observed. The pores of 10 A in radius were predominant in all the gelatins studied. Since the sizes of cellular blood components range between 2 and 17 microns, they can enter the spaces but not the pores of 10 A in radius. On the other hand, water molecules, the major component of plasma, can enter the pores. Of theoretical sorption isotherms, Henderson's and Chung-Pfost's equations were fitted within the range of relative humidity between 1.5 and 75%. Gelatin No. 1 had the smallest constants n, K, B, and C followed by gelatins No. 2 and No. 3, suggesting that gelatin No. 1 is the most flexible for water and thus is fitted most easily to a raw area such as a wound or burn surface. The study of hemostatic effects of gelatin in rats demonstrated that when used at concentrations more than 50% of the bleeding amount, gelatin absorbed water from blood, and was stuck to and covered the wound surface.

Influence of living conditions on the incidence of anemia and effects of health guidance and diet supplementation on recovery from anemia of women in fishing villages

Studies were made on the relationship between the incidence of anemia and living conditions of women in fishing villages in Tokushima prefecture, and also on the effects of health guidance and supplementation of the diet with iron enriched food on recovery from anemia. With regard to economic conditions, Hb values were found to be higher in women who spent more money on food and who had much leisure time compared with working hours. With regard to diet, Hb values were higher in women with higher intakes of animal protein and vitamin C. Intake of vitamin C was significantly higher in a group with hemoglobin value of over 12.0 g/dl than in a group with hemoglobin value of under 12.0 g/dl. The cumulative recovery rate from anemia of women receiving health guidance was 61.5% and the cumulative recovery rate from anemia of women receiving Tsukudani (a preparation of small dried sardines) enriched with iron for 60 to 105 days (30 to 75 mg iron per day: average 59.3 mg per day) was 53.3%. But the recovery rate of serum iron was lower than those of Hb and Ht, being about 40% on the average.

Nutritional epidemiological study on mineral intake and mortality from cardiovascular disease

To clarify the relationship between mortality from cardiovascular disease and mineral intake in Japan, we performed statistical analysis on the intake of 4 minerals, magnesium (Mg), calcium (Ca), sodium (Na) and potassium (K) calculated from the National Nutritional Survey. Their association with age-adjusted mortality from ischemic heart disease (IHD), cerebral hemorrhage (CH) and cerebral infarction (CI) during 15 years between 1971-1985 was examined. Ca/Mg ratio increased in all Japan. Mg intake, Na/K ratio and Na*Ca/K*Mg ratio decreased in all Japan. Geographical correlations among mineral intake were generally highly positive, and a high inverse correlation was observed between Na intake and Ca/Mg ratio. Mineral intake was closely correlated highly positively with mortality from CH and CI for almost all 15 years in men and women. Correlation between mortality from IHD and mineral intake was positively significant only in the period of 1971-75 in some cases. Principal component analysis using the intake in each food group showed the intake of all 4 minerals to be correlated highly with first principal component comprising the Japanese traditional diet. Thus, in Japan, it may be necessary to devise certain aspects of food intake such as lower Na in the Japanese traditional diet and additional Mg in the modern diet.

Comparative studies of larval and pupal phenoloxidase of the housefly, Musca domestica L

1. Larval and pupal phenoloxidase of the housefly, Musca domestica L. resembled each other in some enzymatic properties, such as optimal pH, pH stability, optimal temperature and thermal stability. 2. The pI values of both enzymes were 4.85, as determined by isoelectric focusing. The molecular weights of two enzymes had a similar value (320,000 and 330,000 for larval and pupal phenoloxidase, respectively) and the molecular weights of these subunits had the same value of 60,000. 3. The aminio acid compositions of two enzymes were very similar. N-terminal amino acid sequences of larval and pupal enzymes were Glu-Glu-Ala-Thr-Val-Val-Pro-Asp-Gly- and Ala-Thr-Val-Val-Pro-Asp-Gly-Tyr-Phe-Met-, respectively, and the residues 3-9 (larval phenoloxidase) were in agreement with the residues 1-7 (pupal phenoloxidase).

[Relationship of nutrient intake to serum enzyme activity]

Measurement of the serum enzyme activity is generally used as a screening test for hepatic and biliary diseases. The purpose of this study is to examine the use of serum enzyme activity as indices of health by analyzing relationships to changes in nutrient intakes. The results obtained were as follows: In cross-sectional studies gamma-GTP (1) and LDH-4 and -5 isozyme levels had a significant negative correlation to dietary intakes of vitamin C and protein, but total serum gamma-GTP and LDH activities had no correlation. Intake trials of these nutrients showed that high intake levels of vitamin C related to decrease in isozymes levels while low protein intake resulted in increases. Serum GPT activity had a negative relationship to vitamin C intake in men, but was not correlated with nutrient intakes in women. Serum ALP activity was affected positively with vitamin B intake in 40-79 year old men and women. There were statistically significant correlations between serum cholinesterase activity and energy, and food intake patterns.

[Effectiveness of dapsone on refractory immune thrombocytopenia in a patient with systemic lupus erythematosus associated with sarcoidosis]

A 57-year-old man was admitted with massive nasal bleeding and blurred vision in January, 1991. Laboratory examination showed a prominent decrease of platelet number (1,000/microliters) and a marked elevation of PAIgG (4,025 ng/10(7) cells). Serological test revealed positive antinuclear factor, low concentration of C3 and C4, high level of immune complex and polyclonal hypergammaglobulinemia. The patient had uveitis and bilateral hilar lymphadenopathy with a high level of serum lysozyme and negative PPD skin test. The diagnosis of SLE complicated with thrombocytopenia and sarcoidosis was made. In spite of the various trials of treatment, such as oral prednisolone (PSL), methyl-PSL pulse therapy, plasma exchange, high-dose intravenous gammaglobulin, cyclophosphamide, azathioprine, vincristine, colchicine, cyclosporine-A, mizoribine, danazol, ascorbic acid and interferon alpha 2b, the platelet number could not be raised enough to keep more than 10,000/microliters, though the level of PAIgG decreased to 200 ng/10(7) cells. Finally, the administration of 75 mg/day of dapsone brought about a significant rise in platelet number within 2 weeks. The maximum number of 6.2 x 10(4)/microliters was obtained after 2 months. Then the patient stopped himself to take the drug, but the platelet number remained around 4-5 x 10(4)/microliters. Same dose of the drug was again prescribed to confirm the effect of dapsone. The platelet number increased to 7.9 x 10(4)/microliters in 2 weeks, and gradually returned to 5 x 10(4)/microliters after cessation of the drug. Thus being certainly effective against thrombocytopenia, dapsone should be considered as one of the therapeutic choice for refractory autoimmune thrombocytopenia.

[A case of motor neuropathy with pyramidal sign due to prolonged administration of high dose of pancuronium bromide (Myoblock)]

We reported a case of motor neuropathy with pyramidal sign following prolonged administration of a high dose of muscle relaxant, pancuronium bromide (Myoblock). A 40-year-old male was admitted to our hospital with acute episode of pancreatitis. He was treated with artificial ventilation and Myoblock to manage delirious state, disseminated intravascular coagulation and multiple organ failure. Total dose of 823 mg (24 mg/day) of Myoblock was given intravenously over 36 days. After Myoblock was discontinued, he regained his consciousness and marked muscle weakness with atrophy was noted in both limbs, more severe in distal lower limbs, without any noticeable sensory and sphincter disturbances. Motor nerve conduction studies showed normal nerve conduction velocities with markedly decreased amplitude of compound muscle action potentials. Repetitive nerve stimulation studies revealed decrement response after tetanic stimulation, which disappeared later. Needle EMG showed active denervation potentials and marked polyphasic motor unit potentials. Muscle biopsy revealed neurogenic muscle atrophy with fragmented acetylcholine esterase-positive postsynaptic sites. Sural nerve biopsy showed slight to moderate degree of axonal degeneration of myelinated fibers. Clinical, electrophysiological, and pathological studies above indicated that the main affected sites were neuromuscular junctions including the terminal twigs of motor neurones and postsynaptic membrane, and pyramidal tracts, predominant in lower limbs. About one month after the recognition of the muscle weakness, his muscle strength improved gradually, however, spasticity with hyperreflexia and pathologic reflexes of both legs were found, and became more prominent thereafter. Intensive physiotherapy and rehabilitation led improvement to the point that he became able to ambulate with walking-aids about 7 months later, but marked spasticity persisted.(ABSTRACT TRUNCATED AT 250 WORDS)

Study on digestibility and energy availability of pulses (peanuts and kidney beans) in men

Four male Japanese students were fed a semisynthetic diet that included rice and whole eggs as protein sources for seven days (basal diet period), and in the following seven days (test diet periods), peanuts and then, kidney beans replaced part of the sugar in the basal diet. Urine and feces were collected throughout the periods and the contents of nitrogen, fat and energy in these excreta were determined. The results obtained were: 1) Digestibility of protein was 95.1 +/- 7.9% for peanuts and 84.8 +/- 3.7% for kidney beans. 2) Digestibility of fat was 83.5 +/- 8.5% for peanuts and 82.4 +/- 9.1% for kidney beans 3) The ratio of the total available energy to intake energy (Net Energy Availability) was 86.1 +/- 6.3% for peanuts and 84.8 +/- 3.1% for kidney beans.

Isolation of cDNA encoding a binding protein specific to 5'-phosphorylated single-stranded DNA with G-rich sequences

We have isolated the cDNA encoding a binding protein to the sequence motif of the immunoglobulin S mu region by the southwestern method. The binding protein designated S mu bp-2 specifically binds to 5'-phosphorylated single-stranded DNA containing 5'-G and GGGG stretches. The amino acid sequence deduced from the cDNA sequence showed that the S mu bp-2 belongs to the putative helicase superfamily which is involved in replication, recombination and repair. Expression of S mu bp-2 mRNA is ubiquitous and augmented in spleen cells stimulated with lipopolysaccharide and interleukin 4 which also induce class switching. The S mu bp-2 gene is conserved among vertebrates. Possible involvement of S mu bp-2 in class switching is discussed.

Binding of suprofen to human serum albumin. Role of the suprofen carboxyl group

The binding of suprofen (SP), a non-steroidal anti-inflammatory drug of the arylpropionic acid class, and its methyl ester derivative (SPM) to human serum albumin (HSA) was studied by dialysis and spectroscopic techniques. In spite of the remarkable differences in the physicochemical properties of SP and SPM, the binding of each molecule to HSA was quantitatively very similar. Thermodynamic analysis suggests that the interaction of SP with HSA may be caused by electrostatic as well as hydrophobic forces, whereas the interactions with SPM may be explained by hydrophobic and van der Waals forces. Similarities in the difference UV absorption spectra between ligand-detergent micelle and -HSA systems indicate that the SP and SPM molecules are inserted into a hydrophobic crevice on HSA. The same studies suggest that the carboxyl group of SP interacts with a cationic sub-site which is closely associated with the SP binding site. Proton relaxation rate measurements indicate that the thiophen ring and propanoate portion of the SP molecule is the major binding site for HSA. The locations of SP and SPM binding sites were identified by using fluorescence probes which bind to a known site on HSA. The displacement data implied that SP primarily binds to Site II, while the high affinity site of SPM as well as low affinity site of SP are at the warfarin binding site in the Site I area. From binding data with chemically modified HSA derivatives, it is likely that highly reactive tyrosine (Tyr) and lysine (Lys) residues, which may be Tyr-411 and Lys-195, are specifically involved in SP binding. In contrast, these two residues are clearly separated from the SPM binding site. The binding of SP and SPM is independent of conformational changes on HSA that accompany N-B transition. There is evidence that the carboxyl group may play a crucial role in the high affinity binding processes of SP to HSA.

[Changes of nutritional factors related to regional differences in the mortality of cardiovascular disease between 1966 and 1985 in Japan]

Cardiovascular disease has been the leading cause of death since 1946 in Japan. In this paper, the relationship between mortality and nutritional factors was analyzed by 12 different regions in Japan during the period 1966-1985. Data in the Reports of the National Nutritional Survey in Japan were used as the nutritional factors, and calculation was made of age-adjusted mortality from ischemic heart disease (IHD), cerebral hemorrhage (CH) and cerebral infarction (CI). The results obtained were as follows: 1. Correlation coefficients were calculated based on the average value of 20 years in each 12 different regions. Correlation coefficients between the mortality from IHD and intake of total fat and n3-polyunsaturated fatty acids were positively significant for both sexes. Between the mortality from CH and vegetable protein and salt, they were positively significant (p < 0.01) while cholesterol was negatively significant (p < 0.01). Between the mortality from CI and vegetable protein, salt and carbohydrate, they were positively significant (p < 0.01). 2. Correlation coefficients between slopes of CH and slopes of nutrients intakes, indicated cholesterol to be negatively significant (p < 0.05) for women from 1966-1970, and salt to be positively significant for men (p < 0.01) and women (p < 0.05) from 1974-1985. In the period 1966-1970, the correlation coefficient between slopes of IHD and those of Keys' factor was positively significant (p < 0.05) for women. 3. To clarify changes in the relationship between mortality and nutrients, correlation coefficients were calculated each year from 1966 to 1985. Significant positive correlation coefficients for IHD were found with animal protein and saturated fat starting from about 1975. Salt was associated with IHD in the 1960s but not following 1970. Those of nutrients for CH and CI did not change markedly during 18 years. 4. Multiple regression analysis with intake of salt and Keys' factor indicated that the influence of salt on cardiovascular disease to decreased and that that of low serum cholesterol on CH declined. Multiple correlation coefficients with salt and Keys' factor decreased for IHD (men) and CH (women).

[Two cases of acute promyelocytic leukemia in pregnancy and the effect of anthracyclines on fetal development]

Two patients with acute promyelocytic leukemia (APL) in 2nd and 3rd trimester of pregnancy are reported on. Case 1: 38-year-old female consulted our hospital because of bleeding tendency and pancytopenia in April, 1988. She was diagnosed as having APL with disseminated intravascular coagulopathy (DIC) and was found to be in the 14th week of gestation. Combined chemotherapy (BHAC-DMP) including the total dose (440 mg) of daunorubicin (DNR) resulted in intrauterine fetal death at 19 weeks of gestation. The fetus was severely anemic and the bone marrow was hypoplastic. Case 2: A 27-year-old female was diagnosed as having APL with DIC at 29 weeks of gestation. BHAC-DMP including 440 mg DNR achieved complete remission. At 35 weeks of gestation, she delivered a normal infant by Caesarean section. The child had normal hematological findings and showed normal growth. Both cases developed APL accompanied by DIC during pregnancy and were treated with a similar regimen including high dose of anthracyclines. Case 2 treated in the late period of gestation delivered a normal infant, while fetal death resulted in case 1, treated in the early period of gestation. We reviewed the literature regarding chemotherapy using anthracyclines during pregnancy.

Characterization of aldehyde reductase of Sporobolomyces salmonicolor

An NADPH-dependent aldehyde reductase (EC 1.1.1.2) isolated from Sporobolomyces salmonicolor AKU 4429 was further characterized. The enzyme also catalyzed the reductions of D-glucuronate, D-glucose, D-xylose and D-galactose at high concentrations. Km values for D-glucuronate and D-glucose are 345 and 4270 mM, respectively. Quercetin, dicoumarol and some SH-reagents inhibited the enzyme activity. NH2-terminal amino acid sequence analysis showed that the S. salmonicolor enzyme is partially the same as the aldo-keto reductase family proteins in primary protein structure.

Characteristic differences in the mode of quinone reduction and stability between energy-coupled and -uncoupled NADH-quinone reductases from bacterial respiratory chain

Bacterial respiratory chain has two types of NADH-quinone reductase (NQR): one is energy-coupled (type-1) and the other had no energy-transducing capacity, that is, energy-uncoupled (type-2). Each of the NADH-reacting flavoprotein subunits of NQR-1 from Escherichia coli and the marine Vibrio alginolyticus reduced quinone to semiquinone radicals by the one-electron transfer pathway and was very sensitive to preincubation with NADH. On the other hand, the NQR-2 from these bacteria reduced quinone to quinol by the two-electron transfer pathway and was insensitive to preincubation with NADH. Since the NQR-1 from E. coli functions as a proton pump, whereas that from the marine V. alginolyticus functions as a sodium pump, the formation of semiquinone radicals as an intermediate is likely to be a common mechanism to functioning as either proton or sodium pump.