Biodiversity of an Acinetobacter population isolated from activated sludge

A culturable microbial community from a sewage treatment plant collecting mainly surfactant-enriched wastes was selected on minimal medium containing two nonylphenol ethoxylates as sole carbon source. Biodiversity of the community was assessed on fifty randomly chosen isolates by a combination of molecular techniques. Isolates were first analysed by amplified 16S ribosomal DNA restriction analysis (ARDRA); most of them (75%) were assigned to the genus Acinetobacter on the basis of 16S ribosomal DNA sequencing. Random amplified polymorphic DNA (RAPD) fingerprinting and the analysis of plasmid content showed a high degree of genetic variability and suggested a marked horizontal gene transfer.     

Effects of cadmium on the growth and uptake of cadmium by microorganisms

Six species of microorganisms, Escherichia coli, Bacillus cereus, Lactobacillus acidophilus, Staphylococcus aureus, Streptococcus faecalis and Actinomyces niger, were grown under suitable conditions in appropriate media. Cadmium chloride was added to provide 0, 5, 10, 20, 40, and 80 mug of Cd per ml. At 40 and 80 mug of Cd per ml, E. coli and B. cereus grew well and the other species were repressed. Cd uptake patterns differed significantly among the species tested. The significance of these data with respect to Cd in food chains is discussed.     

Numerical taxonomy of Skermania piniformis and related isolates from activated sludge

This study compared 21 female adult psychiatric patients diagnosed with dissociative identity disorder (DID) with 21 female adult nondissociative psychiatric patients to determine whether DID patients exhibit a distinguishing set of clinical features, and perceptual, attentional, and cognitive processes. Participants were assessed with the Dissociative Disorders Interview Schedule to assess diagnostic status. Group scores on the Dissociative Experiences Scale, Tellegen Absorption Scale, Childhood Trauma Questionnaire, Brief Symptom Inventory, and the Rorschach test were compared. DID participants reported earlier and more severe childhood trauma, more dissociative symptoms, and a greater propensity for altered states of consciousness. The DID participants also exhibited increased projective and imaginative activity, a diminished ability to integrate mental contents, a complex and driven cognitive style, and a highly unconventional view of reality.     

Isolation and identification of bacteria from activated sludge purifying petroleum wastewaters

Several strains growing well in minimal media with 500 and 1000 mg/l of oil or phenol as a sole carbon source were isolated from activated sludge purifying petroleum waste waters and identified. Five of the best growing strains classified as Arthrobacter, Pseudomonas, Xanthomonas and Enterobacter were selected and their capacity to remove petroleum components and phenol (in the oil fraction of petrochemical waste waters) was studied. The enzymatic activity of the strains, including respiration intensity and dehydrogenase activity was also determined. All the examined strains were found to use oils as the sole source of carbon (percent age of the oils reduction during cultivation of the individual strains ranged from 58 to 78). Phenol was completely reduced by only one strain. The rest of the strain removed only from 7 to 24% of this compound. The activity of dehydrogenases and the respiration intensity in the presence of the studied substrates -- oil and phenol was low for all the examined strains.     

Influence of cadmium on resistance to antibiotics in salmonellae isolated from pigs

Repeated cultivations (4 passages) of salmonellae (18 strains) resistant to cadmium, streptomycin and beta-lactam antibiotics in Müller-Hinton Broth (MHB) and Mac-Conkey Broth (MCB) without and with CdSO4 (2, 20 and 100 mg/L) showed a higher toxic effect of cadmium in MCB. The strains survived at CdSO4 100 mg/L in MHB for four transfers, in MCB only a single transfer. In dependence on the medium used and amount of metal added, the increase of resistance to antibiotics was different. In MHB, the same levels of resistance to carbenicillin and streptomycin were induced by CdSO4 (20 and 100 mg/L), in MCB it was by 2 and 20 mg/L. Simultaneous stop of the growth of a control culture S. typhimurium with chromosomal resistance to streptomycin, isolates with and without plasmid in MCB which contained CdSO4 100 mg/L, and the results of conjugal transfer of resistance suggest that changes of resistance to antibiotics were not mediated by determinants of resistance to antibiotics. The binding of cadmium to outer membrane protein can cause a decreased permeability to these antibiotics as a resistance mechanism.     

Selenite bioremediation potential of indigenous microorganisms from industrial activated sludge

Ten bacterial strains were isolated from the activated sludge waste treatment system (BIOX) at the Exxon refinery in Benicia, California. Half of these isolates could be grown in minimal medium. When tested for selenite detoxification capability, these five isolates (members of the genera Bacillus, Pseudomonas, Enterobacter and Aeromonas), were capable of detoxifying selenite with kinetics similar to those of a well characterized Bacillus subtilis strain (168 Trp+) studied previously. The selenite detoxification phenotype of the Exxon isolates was stable to repeated transfer on culture media which did not contain selenium. Microorganisms isolated from the Exxon BIOX reactor were capable of detoxifying selenite. Treatability studies using the whole BIOX microbial community were also carried out to evaluate substrates for their ability to support growth and selenite bioremediation. Under the appropriate conditions, indigenous microbial communities are capable of remediating selenite in situ.     

Effects of sodium chloride and relative humidity on growth and sporulation of moulds isolated from cured fish

1. The aim of this study was to determine plasma levels of N-terminal atrial natriuretic peptide and atrial natriuretic peptide in normal subjects and in patients with essential hypertension, cardiac transplant and chronic renal failure, using radioimmunoassays directed towards the mid-portion pro-atrial natriuretic peptide (31-67) and pro-atrial natriuretic peptide (1-30) of the N-terminal atrial natriuretic peptide and atrial natriuretic peptide (99-126). The circulating form(s) of the immunoreactive N-terminal atrial natriuretic peptide in plasma extracts has been investigated using all three radioimmunoassays by means of gel filtration chromatography to further clarify the major immunoreactive molecular circulating form(s) of N-terminal atrial natriuretic peptide in man. 2. The plasma level (mean +/- SEM) of N-terminal pro-atrial natriuretic peptide (31-67) in the normal subjects was 547.2 +/- 32.7 pg/ml (n = 36) and was significantly elevated in patients with essential hypertension (730.2 +/- 72.3 pg/ml, P < 0.025, n = 39), in cardiac transplant recipients (3214.0 +/- 432.2 pg/ml, P < 0.001, n = 9) and in patients with chronic renal failure (3571.8 +/- 474.1 pg/ml, P < 0.001, n = 11). Plasma levels of N-terminal pro-atrial natriuretic peptide (1-30) and atrial natriuretic peptide were similarly elevated in the same patient groups when compared with the mean plasma values in the normal subjects.(ABSTRACT TRUNCATED AT 250 WORDS)     

Microbial quantification in activated sludge: the hits and misses

Since the implementation of the activated sludge process for treating wastewater, there has been a reliance on chemical and physical parameters to monitor the system. However, in biological nutrient removal (BNR) processes, the microorganisms responsible for some of the transformations should be used to monitor the processes with the overall goal to achieve better treatment performance. The development of in situ identification and rapid quantification techniques for key microorganisms involved in BNR are required to achieve this goal. This study explored the quantification of Nitrospira, a key organism in the oxidation of nitrite to nitrate in BNR. Two molecular genetic microbial quantification techniques were evaluated: real-time polymerase chain reaction (PCR) and fluorescence in situ hybridisation (FISH) followed by digital image analysis. A correlation between the Nitrospira quantitative data and the nitrate production rate, determined in batch tests, was attempted. The disadvantages and advantages of both methods will be discussed.     

Biodegradation of phthalic acid esters in river water and activated sludge

Infants born in New England with congenital heart defects were examined for association with time of year or population density. Moderate seasonal peaks in births were noted for complex ventricular septal defect, malposition defects, and transposition of the great arteries. Positive associations with population density were found for pulmonary atresia with ventricular septal defect, ventricular septal defect with secondary anomalies, and tricuspid atresia.     

Effects of pentoxifylline on sperm motility and hyperactivated motility in vitro: a preliminary report

Previous reports (2, 3) have suggested that pentoxifylline increases sperm motility. In this preliminary report based on five asthenozoospermic and five normal motility semen samples, we were unable to demonstrate any statistically significant effect of pentoxifylline on percent motility of human spermatozoa. However, in vitro exposure to capacitation medium with pentoxifylline may lead to an increase in total hyperactivated motility in asthenozoospermic samples, an effect not evident in the normal motility samples in this study.     

Inhibition of anaerobic phosphate release by nitric oxide in activated sludge

Activated sludge not containing significant numbers of denitrifying, polyphosphate [poly(P)]-accumulating bacteria was grown in a fill-and-draw system and exposed to alternating anaerobic and aerobic periods. During the aerobic period, poly(P) accumulated up to 100 mg of P x g of (dry) weight. When portions of the sludge were incubated anaerobically in the presence of acetate, 80 to 90% of the intracellular poly(P) was degraded and released as orthophosphate. Degradation of poly(P) was mainly catalyzed by the concerted action of polyphosphate:AMP phosphotransferase and adenylate kinase, resulting in ATP formation. In the presence of 0.3 mM nitric oxide (NO) in the liquid-phase release of phosphate, uptake of acetate, formation of poly-beta-hydroxybutyrate, utilization of glycogen, and formation of ATP were severely inhibited or completely abolished. In cell extracts of the sludge, adenylate kinase activity was completely inhibited by 0.15 mM NO. The nature of this inhibition was probably noncompetitive, similar to that with hog adenylate kinase. Activated sludge polyphosphate glucokinase was also completely inhibited by 0.15 mM NO. It is concluded that the inhibitory effect of NO on acetate-mediated phosphate release by the sludge used in this study is due to the inhibition of adenylate kinase in the phosphate-releasing organisms. The inhibitory effect of nitrate and nitrite on phosphate release is probably due to their conversion to NO. The lack of any inhibitory effect of NO on adenylate kinase of the poly(P)-accumulating Acinetobacter johnsonii 210A suggests that this type of organism is not involved in the enhanced biological phosphate removal by the sludges used.     

Increased oxidant resistance of alveolar macrophages isolated from rats repeatedly exposed to cadmium aerosols

This study investigated potential mechanisms of oxidant resistance in alveolar macrophages (AM) isolated from Lewis rats exposed repeatedly to cadmium aerosols. Macrophages from Cd-adapted animals significantly greater resistance to oxidant-induced cytotoxicity than control cells when challenged with hydrogen peroxide in vitro. Elevations in glutathione peroxidase and glutathione reductase activities were associated with increased oxidant tolerance but catalase activity was unchanged. Metallothionein (MT) expression (protein and mRNA) was dramatically up-regulated in response to in vivo Cd exposure. A study using immunocytochemistry and in situ hybridization techniques revealed significantly heterogeneity in the expression of metallothionein by AMs. The percentage of AMs positive for MT (protein and mRNA) and the degree of MT expression within individual cells increased in response to additional Cd exposures. A putative state of activation was suggested by differences in size and number of inclusion bodies in macrophages from Cd-adapted animals and by secretion of a cytokine with interleukin-1-like characteristics. In summary, AMs from Cd-adapted animals are distinguished from control cells with respect to: (1) increased oxidant resistance, (2) secretion of cytokines, (3) elevations in enzymes associated with glutathione metabolism, and (4) up-regulation in metallothionein expression.     

Effects of intravenous ketamine on gastrointestinal motility in the dog

OBJECTIVE: The purpose of this trial was to clarify the effects of intravenous ketamine at anaesthetic and sub-anaesthetic dosages on gastrointestinal motility. DESIGN: 20 beagles (group 1: 3 mg/ketamine/kg/h, n = 10; group 2: 30 mg ketamine/kg/h, n = 10), were investigated. Gastric emptying (nuclide gastric emptying studies, liquid and semi-solid test meal), intestinal transit time (Hydrogen breath test with lactulose) and intestinal motor function (perfusion manometry with 8 measuring ports) were determined. As a control condition, the tests were performed on all dogs in the two groups during infusion of physiological saline solution. RESULTS: No significant differences in the motility patterns were present between 3 mg ketamine/kg/h and the control condition. For group 2, a moderately significant (p < 0.05) increase in the interdigestive motility index was observed for 30 mg ketamine/kg/h. However, this did not change the transit criteria. There was no significant difference between ketamine and control condition tests with regard to cycle and phase lengths or the propagation rate of the activity front. CONCLUSIONS: We conclude that ketamine provokes no basic changes in gastrointestinal motility, at either sub-anaesthetic doses. It can therefore be used to advantage in the continuous postoperative analgesia of intensive care patients, where repeated interventions are necessary and no cardiopulmonary contraindications are present.     

Effects of duodenal distention on fasting and postprandial antropyloroduodenal motility in humans

BACKGROUND/AIMS: Mechanoreceptors in the proximal small intestine may play an important role in the regulation of gastric emptying. Balloon distention of the duodenum causes fundic relaxation. The purpose of the present study was to determine the effect of stimulation of duodenal mechanoreceptors on both fasting and postprandial antropyloroduodenal motility in humans. METHODS: Antropyloroduodenal pressures were recorded in 12 healthy volunteers with a sleeve-sidehole assembly, incorporating two balloons 5 and 20 cm distal to the pylorus. Duplicate proximal and distal duodenal balloon distensions with 10, 20, and 30 mL of air for 2.5 minutes were performed separately and in randomized order both during fasting and after a meal. RESULTS: During fasting, proximal and distal distention at all volumes increased the number of isolated pyloric pressure waves (P < 0.05) and basal pyloric pressure (P < 0.05), and the response to proximal distention was greater (P < 0.05). Postprandially, proximal and distal distention increased basal pyloric pressure (P < 0.05) with a greater response to proximal distention (P < 0.05), but had no effect on isolated pyloric pressure waves. Both during fasting and postprandially, there were more synchronous and less antegrade antral waves during distention (P < 0.05). The number of duodenal pressure waves increased during proximal (P < 0.05) but not distal distention. CONCLUSIONS: Stimulation of duodenal mechanoreceptors by balloon distention has significant and region-dependent effects on antropyloroduodenal motility that vary between fasting and postprandial states.     

Effects of cadmium and lead on adrenergic neuromuscular transmission in the rabbit

The effects of inorganic lead (PbCl2) and cadmium (DdCl2) on the pressor response of rabbit saphenous arteries produced by sympathetic nerve stimulation were examined. A 1- to 3-cm length of artery was removed, placed in a bath containing mammalian Ringer solution, and perfused with the same solution at a constant rate sufficient to maintain a 40-60 mmHg perfusion pressure. Increases in perfusion pressure resulting from electrical stimulation -f periarterial nerve endings were reduced or completely blocked by the addition of 5-20 muM lead or cadmium to the bathing solution for a period of 15-30 min. Responses to norepinephrine or to direct electrical stimulation of the muscle remained relatively unaffected. During lead or cadmium blockade, the response to nerve stimulation could be restored by a fourfold increase in calcium concentration. It is concluded that lead and cadmium reduce the response to sympathetic nerve stimulation primarily through an effect on presynaptic nerve terminals.     

Population dynamics of phenol-degrading bacteria in activated sludge determined by gyrB-targeted quantitative PCR

A method for quantifying bacterial populations introduced into an activated-sludge microbial community is described. The method involves extraction of DNA from activated sludge, appropriate dilution of the extracted DNA with DNA extracted from nonintroduced activated sludge, PCR amplification of a gyrB gene fragment from the introduced strain with a set of strain-specific primers, and quantification of the electrophoresed PCR product by densitometry. The adequacy of the method was examined by analyzing the population dynamics of two phenol-degrading bacteria, Pseudomonas putida BH and Comamonas sp. strain E6, that had been introduced into phenol-digesting activated sludge. The density of each of the two populations determined by the PCR method immediately after the introduction was consistent with the density estimated from a plate count of the inoculum. This quantitative PCR method revealed different population dynamics for the two strains in the activated sludge under different phenol-loading conditions. The behavior of both of these strains in the activated sludge reflected the growth kinetics of the strains determined in laboratory axenic cultures.     

Immunomodulatory activity of thunberginol A and related compounds isolated from Hydrangeae Dulcis Folium on splenocyte proliferation activated by mitogens

We have prospectively studied 27 adult patients attending the Department of Infectious Diseases, G?teborg, Sweden, between October 1992 and October 1996 with a diagnosis of acute viral encephalitis. In addition to cerebrospinal fluid (CSF) virus isolations and antibody analyses against herpes simplex virus, cytomegalovirus, varicella zoster virus, Epstein-Barr virus (EBV), enterovirus, adenovirus, tick-borne encephalitis virus, and mycoplasma, polymerase chain reaction test (PCR) to 5 viruses from the family of human herpes viridae, and to adenovirus as well as to enterovirus were analysed in CSF. 10 patients had herpes simplex virus type-1 (HSV-1), 1 had varicella zoster virus, 1 had tick-borne encephalitis, and 2 had Influenza A infections. In 13 patients the aetiology remained unclear. Eight patients with HSV-1 encephalitis and clinical symptoms for 2-11 d before admission were PCR-positive, while 2 patients with a < or = 2 d history of disease were negative for HSV-1 DNA on admission. These 2 patients became positive for HSV-1 DNA in CSF samples taken 4 d later in 1 case and 7 d later in the other. In 4 patients with HSV-1 encephalitis, in 1 patient with Influenza A complicated by encephalitis, and in 1 patient with encephalitis of unknown origin EBV DNA was found in CSF samples during the study. The clinical significance of these findings is unclear. The study shows that HSV-1 was the most common etiological agent in patients with viral encephalitis in the G?teborg area. In spite of improved diagnostic procedures, a large proportion of patients with symptoms and laboratory findings compatible with viral encephalitis still have an unclear aetiology.     

Effects of hydrogen and carbon on thermally activated deformation in nickel

Deformation experiments were performed to determine the effects of hydrogen and carbon on the activation parameters for dislocation slip in nickel. The techniques used were isothermal stress relaxation and differential temperature measurements. These methods allowed determination of the activation enthalpy and activation area for dislocation motion in nickel and the effects of hydrogen and carbon on these parameters. The results show that hydrogen increases the dislocation mobility in Ni and in NiC alloys by reducing the activation enthalpy for dislocation motion, while carbon reduces the dislocation mobility by increasing the activation enthalpy. Hydrogen solutes decrease the activation area for dislocation motion in both pure Ni and in NiC alloys.