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At least 19 recordsLinked to original sources
PubMed1978

Studies on the adjuvant effect of water-in-oil-in-water (w/o/w) emulsion of sesame oil. 1. Enhanced and persistent antibody formation by antigen incorporated into the water-in-oil-in-water emulsion.

Water-in-oil-in-water (w/o/w) emulsion developed in our laboratory is as effective as water-in-oil (w/o) emulsion of Freund's incomplete adjuvant (FIA) in the stimulation of antibody formation. The emulsion is prepared by redispersion of water-in-sesame oil emulsion of an antigen solution in phosphate buffered saline with emulsifier, Tween 80. The emulsion can be stored at 4 degrees C for at least 3 months without any evidence of change in the adjuvanticity and in the w/o/w state. Even a single injection of bovine serum albumin (BSA) in the w/o/w emulsion elicited a high antibody response in mice over the period of almost whole lifespan. 10 microgram BSA in w/o/w could stimulate antibody formation up to 2(12) in hemagglutination titer, while the same dose in free solution did not elicit any detectable antibody. The tissue reactions caused by the w/o/w emulsion at the injected site and in the regional lymph nodes were much less prominent than those by FIA.

Adjuvants, Immunologic↗
PubMed1992

Effect of hepatic portal infusion of water on water intake by water-deprived rats.

To determine whether or not hepatoportal osmoreceptive (or sodium-receptive) signals participate in the control of drinking, we examined the effects of portal infusion of water, 0.9% saline, and 1.8% saline on water intake by water-deprived rats. Infusion was started 0.5 h prior to the end of the water deprivation period for 3.5 h at a rate of 52 microliters/min through either a portal or a jugular catheter. After 24-h water deprivation, water intake was measured successively for 24 h without food. As a result of the water infusion tests, water intake of the portal infusion group was significantly less than that of the jugular infusion group during and after the infusion. Portal infusion of neither 0.9% nor 1.8% saline affected the water intake compared to similar infusion into the jugular vein. It is concluded that hypotonic stimulation of the hepatoportal osmoreceptor suppresses water intake in water-deprived rats. On the contrary, isotonic or hypertonic stimulation does not produce any change of water intake.

Animals↗
PubMed1976

[Considerations on critics towards conditioned waters (drinking water in general and particularly mineral water) especially from the microbiological point of view].

After having precised what has incited to extend our considerations reported at the International Congress on Microbiology for Mineral Waters to all the conditioned waters, in a "first part" we have examined the drawbacks imputed to the water itself. a) In a first analytical chapter, we have made the schedule and the critical examination of the different reproaches given to conditioned waters on considering successively: 1) Special drawbacks (although these are of an other category than microbiology) which were given, whichever type of supply (loose, at the tap, or splitted up when the water is conditioned), to some categories of waters (carbonated and mineral) because of their nature by the fact that these waters do not show the charactheristics of potability with regard to the legislation and administration. This examination leads to eliminate those reproaches because the consumer knows to which he is exposed, being forewarned: -when he is using mineral water at the cure-resort, by the thermal consultant who is watching over him, -when he is using one or the other of the conditioned waters, -either by the medical practictioner, who should give him the contre-indicates; -either by indicating on the label, if not the contre-indicates (like we would hope that they figure on), at least the composition (which now figures within the EEC).

Food Inspection↗
PubMed1975

[The behavier of Pseudomonas aeruginosa in surface water, cooling water and waste water (author's transl)].

This is a report on the occurrence and numerical behaviour of Ps. aeruginosa in natural waters with and without waste water contamination, in dams, cooling water circulations and cooling water discharge, in clarification plant and supplementary laboratory tests. The results show that Ps. aeruginosa may occur in the natural flora of open waters, but only following the introduction of human sewage. In the main, a more or less rapid reduction in the number of Ps. aeruginosa to low levels occurs, but periods of several days to several weeks must be allowed for this. In the presence of large quantities of nutrient, multiplication of Ps. aeruginosa in natural waters cannot be excluded. It certainly appears in technical systems such as cooling water circuits and filter plants. Presumably Ps. aeruginosa also multiplies in waste water, whereas in the biological aerobic clarification process a reduction occurs. The effect of a higher temperature on the survival or multiplication of Ps. aeruginosa could not be confirmed by laboratory experiments.

Cell Count↗
PubMed1992

Effect of vitamin D3 administration on the serum calcium and inorganic phosphate levels of the freshwater catfish, Heteropneustes fossilis, maintained in artificial fresh water, calcium-rich fresh water, and calcium-deficient fresh water.

Freshwater catfish, Heteropneustes fossilis, were injected daily intraperitoneally either with vehicle (0.05 ml of 95% ethanol/100 g body wt) or vitamin D3 (50 I.U./100 g body wt) and maintained in artificial fresh water, calcium-rich fresh water, or calcium-deficient fresh water for 10 days. The specimens were sacrificed on Days 1, 3, 5, and 10 after initiation of the experiment. The blood samples were collected on these intervals and serum calcium and inorganic phosphate levels were analyzed. Vitamin D3 induced hypercalcemia and hyperphosphatemia in the freshwater catfish, H. fossilis. These effects of vitamin D3 are not dependent upon the calcium concentration of the different ambient media used in this study.

Animals↗
PubMed1975

Water states and water gates in osmotic processes, and the inoperative concept of molfraction of water.

An historical account is given of concepts regarding the mechanism of osmosis and imbibition, starting with Lord Kelvin's gravitational column, where he pointed out that a capillary standing in a dish of water within an isothermal enclosure must have a lowered vapor pressure at its elevated meniscus so as to match that emanating from the surface in the dish, otherwise distillation would violate the Second law. A brilliant sequence to this simple idea followed through Poynting, Arrhenius, Noyes and culminated with Hulett, who in 1901 formulated the "solvent tension theory" of osmosis, stating in essence that the thermal motion of the solute molecules by impact with the free solvent surface put the solvent under tension. This lowers the vapor pressure and thereby also its freezing point. Perrin, in famous experiments on Brownian motion, demonstrated solute-solvent independence within a solution and further support came through Herzfeld, Mysels and Duclaux. We measured negative pressures in salt-free sap of mangroves and other plants matching the osmotic pressure in the leaf cells. A series of measurements on magnetic and gravitational effects on osmotic pressure likewise bore out the tension theory. The fashionable "water concentration theory" is left experimentally contradicted and in violation of the Second law.

Capillary Action↗
PubMedDate not supplied

Surface-chemical studies on chlorhexidine and related compounds: I. Effects at air-water, n-hexane-water, and hydroxyapatite-water interfaces.

The comparative ability of chlorhexidine diacetate and structurally related compounds to generate surface pressure at air-water and n-hexane-water interfaces, and to adsorb to hydroxyapatite, was determined. The order of effectiveness generally evident was 1-(p-chlorophenyl)-5-n-octylbiguanide acetate is greater than chlorhexidine diacetate 1-(p-chlorophenyl)-5-n-hexylbiguanide acetate is greater than 1-(p-chlorophenyl)-5-n-propylbiguanide acetate is greater than p-chlorophenylbiguanide acetate p-chlorophenylguanidine acetate.

Adsorption↗
PubMed1976

[On the growth of various Enterobacteriaceae, Pseudomonas aeruginosa and Alkaligenes spec. in distilled water, de-ionized water, tap water, and mineral salt solution (author's transl)].

The behaviour of 12 strains of gram-negative bacteria was analysed in media having a low content of nutrients. Sterile tap water, de-ionized water, aqua bidestillata and mineral salt solution were used. It was found that Serratia marcescens, Pseudomonas aeruginosa, Enterobacter, Klebsiella and Citrobacter are those with the most frequently observed growth. In the mineral salt solution survived also Providencia, E. coli, Erwinia, Hafnia, and Alkaligenes and reached max. colony numbers of some 100000/ml. When the salts used were added stepwise potassium phosphate and especially magnesium sulfate showed a growth-promoting effect.

Alcaligenes↗
PubMed1992

[Concentration and form of asbestos fibers in tap drinking water contaminated from a water supply pipe with asbestos-cement].

The identification and concentration of asbestos fibers in tap drinking water supplied in a central area of Akita Prefecture, Japan, were determined by phase-contrast microscopy and a scanning electron microscope equipped with an energy-dispersive X-ray microanalyzer. The following results were obtained. 1. Asbestos fibers were found in the tap water from two areas in which an asbestos-cement pipe was used for public water supply. The concentrations of asbestos fibers in the tap water were 2.7 x 10(4) to 27.0 x 10(4) fibers per liter of water in area A and 10.0 x 10(4) to 21.0 x 10(4) in area B. On the other hand, no asbestos fiber contamination was observed in tap water of area C, which shared a common water source with area A. A vinyl chloride pipe was used over the entire length of the water supply in route C. 2. Crocidolite was the predominant type of asbestos fiber detected in the tap water. Chrysotile and a mixture of chrysotile and amosite were also observed. 3. Almost all asbestos fibers detected in the tap water possessed the form of thick or sheaved fibers with lengths ranging from ca. 5 to 10 microns. Their shapes were very different from those of asbestos fibers found in the atmosphere. The typical form of the latter is short (ca. 1 micron in length) and needle-like. 4. It was suggested that the contamination of asbestos fibers in the tap water was caused by erosion and peeling off of the inner wall of the asbestos-cement pipe used as a conduit. In order to evaluate the safety of drinking water in Japan, an extensive survey on asbestos-fiber contamination in tap water is necessary.

Asbestos↗
PubMedDate not supplied

An evaluation of the hydrogen sulphide water screening test and coliform counts for water quality assessment in rural Malaysia.

The H2S water screening test and the membrane filtration faecal coliform count were compared with Escherichia coli counts for water samples collected from household water sources and domestic drinking water in rural Malaysia. Water samples were taken from 151 wells, 44 taps supplying water from the treated municipal supply and 192 domestic stored water supplies. E. coli were detected in 20% of the samples (42% of wells, 7% of tap water and 6% of drinking water). Excellent correlation (Spearman's rank correlation rs = 0.93) was found between the faecal coliform and E. coli counts for all sample types. The H2S method was poorly correlated whether read at 18 or 30 h. False positive rates were highest for well water, and false negative rates were highest for both well and drinking water samples, with low E. coli counts. The faecal coliform test was an excellent predictor of the presence of E. coli in these water samples, while the H2S test was very inadequate.

Enterobacteriaceae↗
PubMed1975

Role of metal ions in Escherichia coli alkaline phosphatase. A study of the metal-water interaction by nuclear relaxation rate measurements on water protons.

The binding of metal to alkaline phosphatase from Escherichia coli and the binding of water and orthophosphate to the Me-2+-enzyme binary complex have been examined by water proton relaxation rate (PRR) measurements. Titration of the three paramagnetic metals, Mn2+, Cu2+, and Co2+, into apoalkaline phosphatase and the titrations of apoenzyme into metal have been carried out. Analysis of the spin-lattice relaxation rates for these titrations and of Scatchard binding curves derived from these results, as well as EPR data, show four tight manganese sites, between two and three tight copper sites, or four cobalt sites per enzyme dimer of molecular weight 80,000. The multiple sites for each metal are indistinguishable by these magnetic resonance techniques. Both the spin-lattice- and spin-spin-relaxation rates exhibit a negative temperature coefficient, showing that these processes are not exchange-limited. From a frequency dependence study of T-1 and from the T-1:T-2 ratio measured at 220 MHz, correlation times from the water-enzyme complexes have been estimated. For H20-Mn-2+-alkaline phosphatase, gamma c equals 1.55 times 10-9 s; for H20-Cu-2+ -alkaline phosphatase, gamma c equals 1.82 times 10-s; and for the cobalt complex, gamma c equals 1.0 times 10-12 s at 4 degrees. Assuming 1 water molecule bound per metal site, these correlation times correspond to the following water-metal distances: gamma (A) is 4.0 A for Mn-2+-H20, 3.4 A for Cu-2+-H20, and 2.8 A for Co-2+-H20. Thus, water is shown to bind directly to the metal atoms of alkaline phosphatase. The correlation between the length of the water-metal bond and the relative activity of the various metalloenzymes support the importance of this binding in the monophosphoesterase reaction catalyzed by alkaline phosphatase. Addition of excess orthophosphate to any of the water-metalloenzyme complexes does not displace an exchangeable water molecule from the metal site. The Mn-PO-4 distance which we have reported earlier (Zukin, R.S., Hollis, D.P., and Gray, G.A. (1973) Biochem. Biophys. Res. Commun. 53, 238) to be 7.3 A is consistent with this finding and suggests a model in which Pi binds to Mn-2+-alkaline phosphatase through a water bridge.

Alkaline Phosphatase↗
PubMed1979

Scientific basis for the study of demineralization of highly mineralized water for use in public water supply systems.

New criteria (full physiological value and preservation of the properties of drinking water) are scientifically substantiated. Also discussed are indices (minimal admissible and optimal levels of basic water mineralization and calcium content, standards of microelements such as boron and bromine content, content of individual groups of microorganisms, water temperature) for evaluating the quality of demineralized water obtained from brackish and briny water (including water from the sea and ocean) by various methods which are designed for public water supply systems. Research results served as the scientific hygiene basis for the development of a new technology of obtaining drinking water. The necessity for developing a special quality standard for demineralized drinking water is shown.

International Cooperation↗
PubMed1979

Levels of benzo(a)pyrene in oil shale industry wastes, some bodies of water in the Estonian S.S.R. and in water organisms.

Data on the content of benzo(a)pyrene (BP) in oil shale industry wastewater, the effectiveness of various effluent treatment processes (evaporation, extraction with butyl acetate, trickling filters, aeration tanks) in reducing the level of BP in oil shale wastewater, the level of BP in various bodies of water of Estonia, and in fish and other water organisms are reviewed. The quantitative determination of BP in concentrated diethyl ether extracts of water samples was carried out by ultraviolet and spectroluminescence procedures by use of the quasi-linear spectra at -196 degrees C in solid paraffins. It has been found that oil shale industry wastewater contains large amounts of BP. The most efficient purification process for removing the BP in oil shale industry phenol water is extraction with butyl acetate. The level of BP in the rivers of the oil shale industry area is comparatively higher than in other bodies of water of the Republic. The concentration of BP in the lakes of the Estonian S.S.R. is on the whole insignificant. Even the maximum concentration found in our lakes is as a rule less than the safety limit for BP in bodies of water (0.005 microgram/l). During water is treated at the waterworks. The effectiveness of the water treatment in reducing the level of BP varies from 11 to 88%. Filtration was found to be the most effective treatment. About 20 samples of fish from nine bodies of water in Estonia have been analyzed for content of BP. The average content of BP in the muscular tissue of various species of fish is as a rule less than 1 microgram/kg. There is no significant difference in the concentration of BP in sea and freshwater fish. There is no important difference in the content of BP in the organs of various fish. Fat fish contain more BP than lean ones. The weight (age) of fish does not influence the content of BP in the muscular tissue of fish.

Animals↗
PubMed1979

Membrane pathways for water and solutes in the toad bladder: II. Reflection coefficients of the water and solute channels.

Urea and water transport across the toad bladder can be separately activated by low concentrations of vasopressin or 8 Br-cAMP. Employing this method of selective activation, we have determined the reflection coefficient (sigma) of urea and other small molecules under circumstances in which the bladder was transporting urea or water. An osmotic method for the determination of sigma was used, in which the ability of a given solute to retard water efflux from the bladder was compared to that of raffinose (sigma = 1.0) or water (sigma = 0). When urea transport was activated (low concentration of vasopressin), sigma for urea and other solutes was low, (sigma urea, 0.08--0.39; sigma acetamide, 0.55; sigma ethylene glycol, 0.60). When water transport was activated (0.1 mM 8 Br-cAMP) sigma urea approached 1.0 sigma urea also approached 1.0 at high vasopressin concentrations. In a separate series of studies, sigma urea was determined in the presence of 2 x 10(-5) M KMnO4 in the luminal bathing medium. Under these conditions, when urea transport is selectively blocked, sigma urea rose from a value of 0.12 to 0.89. Thus, permanganate appears to "close" the urea transport channel. These findings indicate that the luminal membrane channels for water and solutes differ significantly in their dimensions. The solute channels, limited in number, have relatively large radii. They carry a small fraction (approximately 10%) of total water flow. The water transport channels, on the other hand, have small radii, approximately the size of a water molecule, and exclude solutes as small as urea.

Animals↗
PubMed1977

Water hardness and cardiovascular disease. Elements in water and human tissues.

The hypothesis that the hardness of drinking water has a causal role in the development of cardiovascular disease will be strengthened if it can be demonstrated that elements in drinking water find their way into human tissues in significant amounts. For biologically important metals, the evidence is reviewed for a relationship of tissue levels to levels in drinking water. Hard water can contribute significantly to daily magnesium intake. Residents of hard-water areas may have raised levels of magnesium in coronary arteries, bone, and myocardial tissue. Lead levels in bone and in blood have been shown to be elevated in individuals living in homes with lead plumbing and soft water. Cadmium intake from water is probably small compared to that from other sources, and there is no convincing evidence of alteration in human tissue levels via drinking water cadmium. Human zinc and copper tissue levels are of interest but have not been adequately studied in relation to drinking water levels.

Bone and Bones↗