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PubMed1994

Changes in trypsin and chymotrypsin inhibitory activity on soaking of sorghum (Sorghum bicolor L. Moench).

Changes in trypsin and chymotrypsin inhibitory activity of sorghum (Sorghum bicolor L. Moench) seeds on soaking in distilled water, different salt solutions and mixed salt solution were investigated. A greater reduction in proteinase inhibitory activity was observed on soaking in salt solution than on soaking in distilled water. Maximum loss of trypsin and chymotrypsin inhibitory activity was observed on soaking seeds in mixed salt solution.

Chymotrypsin↗

PubMed1995

Effects of various water or hydrothermal treatments on certain antinutritional compounds in the seeds of the tribal pulse, Dolichos lablab var. vulgaris L.

Effects of soaking, cooking and autoclaving on changes in polyphenols, phytohaemagglutinating activity, phytic acid, hydrogen cyanide (HCN), oligosaccharides and in vitro protein digestibility were investigated in seeds of Dolichos lablab var. vulgaris. Both distilled water and NaHCO3 solution soaking and autoclaving significantly reduced the contents of total free phenolics (85-88%) compared to raw seeds. Autoclaving (45 min) reduced the content of tannins by upto 72%. Soaking seemed to have limited effect in eliminating phytohaemagglutinating activity, whereas autoclaving (45 min) seemed to eliminate the haemagglutinating activity completely. The reduction in content of phytic acid was found to be some what greater in distilled water soaking (28%) compared to NaHCO3 solution soaking (22%). Only a limited loss in content of phytic acid was observed under cooking as well as autoclaving. Loss of HCN was greater under autoclaving (87%) compared to the other processes studied. Of the three sugars analysed, soaking reduced the level of verbascose more than that of stachyose and raffinose. Autoclaving reduced the content of oligosaccharides more efficiently (67-86%) than ordinary cooking (53-76%). Autoclaving improved the in vitro protein digestibility (IVPD) significantly (13%). Of all the different water and hydrothermal treatments studied autoclaving seemed to be the most efficient method in improving IVPD and eliminating the antinutrients investigated except phytic acid.

Fabaceae↗

PubMed1987

Determination of the formaldehyde content in fishery products.

The influence of external factors, such as storage temperature and time on the content of free formaldehyde (FA) in fishery products is described. On the basis of the examination of several methods for the determination of free and bound FA, the following procedures are recommended: (1) for measuring free FA, the samples are extracted using 6% perchloric acid at room temperature and the FA content of the extracts is measured by the formation of 3,5-diacetyl-1,4-dihydrolutidine; (2) bound, acid-labile FA is released by steam distillation using 1% sulphuric acid, giving a pH value of about 1. The FA content of the distillates may be determined either by chromotropic acid assay or by the method described for the extracts.

Amino Acids↗

PubMed1988

Purification of water for in vitro fertilization and embryo transfer.

The purpose of this study was to determine whether water obtained from the Milli-Q water purification system (Millipore, Mississauga, Canada) needed further purification for use in in vitro fertilization and embryo transfer. We describe a method for maintenance of the Milli-Q system. To assess water quality, alternate batches of culture media were prepared by using either Milli-Q water or Milli-Q water further treated by twice glass distillation. The percentage of mouse two-cell embryos that developed to blastocysts and the human in vitro fertilization-embryo transfer pregnancy rates were recorded for each batch. There were no significant differences in the parameters examined, indicating that further purification by twice glass distillation is not necessary if the Milli-Q system has been maintained as outlined.

Culture Media↗

PubMed1991

An evaluation of hamster, rat, and mouse sperm-cell motility in media formulated with water of different qualities.

The in vitro motility of caudal epididymal spermatozoa from four hamsters, four rats, and four mice was compared in modified Tyrode's medium (TLP-PVA) prepared with water of three qualities: (1) Sigma tissue culture water, 18 m omega, high quality (HQ); (2) deionized distilled water, 4.5 m omega prior to distillation, intermediate quality (IQ); and (3) tap water, low quality (LQ). The objective was to evaluate the in vitro bioassay potential of spermatozoa from these species, in terms of relative sensitivities to toxins in different qualities of water. An average sperm motility index (SMI) was calculated per treatment at 2, 4, and 6 hr, where SMI = fpm2 x % motility. Hamster SMI could be used to discriminate between HQ and IQ media at 4 and 6 hr (P less than 0.001), while rat SMI could be used to discriminate between HQ and IQ media at 6 hr (P less than 0.05). Mouse SMI did not differ between HQ and IQ media. The ability to discriminate between extremes in quality. HQ or IQ vs LQ, was equal between species (P less than 0.001). These results suggest that hamster spermatozoa provide the more sensitive in vitro bioassay model, while rat and mouse spermatozoa may be used for assay of extremes in water quality.

Animals↗

PubMed1995

Toxic interaction of fumonisin B1 and fusaric acid measured by injection into fertile chicken egg.

Toxic interactions of fusaric acid and fumonisin B1, two mycotoxins produced by Fusarium moniliforme, were studied in the chicken embryo. The yolk sacs of fertile White Leghorn eggs were injected before incubation with separate and combined solutions of either fusaric acid and or fumonisin B1. The toxins were administered in either a sterile 10 mM buffered phosphate solution, pH 6.90, which produced a final pH of 6.6 +/- 0.2, or sterile distilled water. Toxicity was based on absence of egg pip at the end of the 21-day incubation period. Toxins administered in the phosphate buffer solution were more toxic than those administered in distilled water. When both toxins were combined in equal concentrations and injected into eggs, increased toxicity resulted. Fusaric acid was shown to be a mild toxin to the eggs and when a relatively nontoxic concentration of it was combined with graded doses of fumonisin B1, a synergistic toxic response was obtained. Fusaric acid is only moderately toxic to the chicken egg, however its co-occurrence with other fusaria toxins found on corn and other cereals might present possible antagonisms or synergisms. The results of this egg model suggest that fusaric acid might play a role in enhanced and unpredicted toxicity in mammalian systems if it is consumed with other mycotoxins.

Animals↗

PubMed1983

Serum cholinesterase inhibitors in the commercial hexane impurities.

Commercial hexane was concentrated by distillation. The distillation residue (0.43 ml/l original solvent) contains material which inhibits human serum cholinesterase (ChE) "in vitro" with a slight effect on acetylcholinesterase. Phosphorus was detected equivalent to 0.33 mumol monophosphorus compound/litre original solvent. The inhibition was progressive with the enzyme-inhibitor preincubation time. A partial reactivation of the inhibited enzyme was obtained by treatment with hydroxylamine and 2-PAM. The results are coherent with a covalent inactivation by more than one inhibitor which acylate (probably phosphorylate) ChE, although it seems likely that a reversible but unstable inhibitor could also be present in the hexane residue. The results are discussed in the context of the known neurotoxic effects of n-hexane and some organophosphorus esters.

Cholinesterase Inhibitors↗

PubMed1987

Influence of water quality on in vitro fertilization and embryo development for the mouse.

Mouse in vitro fertilization and embryo culture were performed in media prepared with five different water preparations. The results of the experiments improved with the frequency of distillation. Each water preparation was analyzed by the measurement of the electrical conductivities and inorganic ion concentrations and by high-performance liquid chromatography to examine the mutual relation between water quality and the method of water purification. The best results were obtained with Milli-Q water, which had the lowest concentration of inorganic ions and organic compounds. On the contrary, unexpected contamination by organic compounds and zinc ions occurred after multiple distillation, possibly leached from the glassware and silicon tube. The hatching rate seemed to be an appropriate indicator to assess the biological qualities of media for the development of embryos cultured in vitro.

Animals↗

PubMed1985

Determination of residual ethylene dibromide in cereals by glass capillary gas chromatography.

This study describes two methods for the quantitative determination of residual ethylene dibromide (1,2-dibromoethane) in cereals, especially wheat, and in dried fruit. The first method is based on a solvent-extraction technique; in the second a continuous micro steam-distillation--solvent-extraction apparatus is used. The quantitative determination of ethylene dibromide is performed by electron-capture gas chromatography using a glass capillary column coated with CPwax 51. The absolute detection limit for EDB is 0.5 pg and recoveries of 82 and 98% resp. are obtained for samples with EDB added in the range of 10 to 50 micrograms/kg. 75 samples of cereal products and 19 samples of dried fruit have been analysed with the solvent extraction method. For 22 samples the micro steam-distillation-solvent-extraction technique has been used.

Carcinogens↗

PubMed1975

Physico-chemical studies of taste reception. IV. Response of individual phospholipid membrane to a variety of chemical stimuli.

Variations in the membrane potential across model membranes made of Millipore filter paper and various single phospholipids were measured in response to salt, acid and distilled water. The phospholipids used were phosphatidylcholine (c), spingomyelin (SM), phosphatidylethanolamine (PE), and phosphatidylserine (PS). Results were compared with those obtained with the model membrane made of the total lipids extracted from bovine tongue epithelium, which simulated well the receptor potential observed with intact tast organs. The membrane potential of PE- and PS-membranes increased monotonously with increase of the concentration of 1:1 type salt, while that of PC- and SM-membranes exhibited no appreciable change in 1:1 salt solutions. Application of CaC12 to the membranes brought about a varity of response depending on the species of lipids used. PE- and PS-membranes showed a larger change in the membrane potential than PC- and SM-membranes when pH of the solution was varied. Fe-3+ was strongly absorbed on the surface of PC and SM-membranes, while Fe-3+ bound to PE- and PS-membranes was easily removed by an application of salt solution. A transient increase in the membrane potential was observed when distilled water was applied to the membrane adapted to an appropriate salt solution, which was similar to the water response observed in taste cells. PC- and SM-membranes responded to water when the membrane adapted to either NaC1 or CaC12, but PS-membrane responded only when the membrane was adapted to a solution containing CaC12. PE-membrane did not respond to water in any cases examined. The membrane prepared with a mixture of two species of phospholipids responded neither to salt nor to water, while the membranes prepared with the total lipids or a mixture of three species of lipids in appropriate ratio responded to both. The water response of the total lipids membrane vanished in a high temperature medium, while the water response of PC-membrane retained in all temperature ranges examined, i.e. between 20 degrees and 62 degrees C. The results obtained suggest that a mosaic structure, where each domain has different functions against various chemical stimuli, is formed on the surface of the model membrane made of the total lipids.

Animals↗

PubMed1976

Permeability parameters of the toad isolated stratum corneum.

A technique for isolating the stratum corneum from the subjacent layers of the epithelium was developed which permits studying the stratum corneum as an isolated membrane mounted between half-chambers. The method basically consists of an osmotic shock induced by immersing a piece of skin in distilled water at 50 degrees C for 2 min. When the membrane is bathed on each surface by NaCl-Ringer's solution, its electrical resistance is 14.1 +/- 1.3 omega cm2 (n=10). This value is about 1/100 of the whole skin resistance in the presence of the same solution. The hydraulic filtration coefficient (Lp) measured by a hydrostatic pressure method, with identical solutions on each side of the membrane, is 8.8 X 10(-5) +/- 1.5 X 10(-5) cm sec-1 atm-1 (n=10) in distilled water and 9.2 X 10(-5) +/- 1.4 X 10(-5) cm sec-1 atm-1 (n=10) in NaCl-Ringer's solution. These values are not statistically different and are within the range of 1/80 to 1/120 of the whole skin Lp. The stratum corneum shows an amphoteric character when studied by KCl diffusion potentials at different pH'S. The membrane presents an isoelectric pH of 4.6 +/- 0.3 (n=10). Above the isoelectric pH the potassium transport number is higher than the chloride transport number; below it, the reverse situation is valid. Divalent cations (Ca++ or Cu++) reduce membrane ionic discrimination when the membrane is negatively charged and are ineffective when the membrane fixed charges are protonated at low pH.

Animals↗

PubMed1986

Membrane potentials and intracellular Cl- activity of toad skin epithelium in relation to activation and deactivation of the transepithelial Cl- conductance.

The potential dependence of unidirectional 36Cl fluxes through toad skin revealed activation of a conductive pathway in the physiological region of transepithelial potentials. Activation of the conductance was dependent on the presence of Cl or Br in the external bathing solution, but was independent of whether the external bath was NaCl-Ringer's, NaCl-Ringer's with amiloride, KCl-Ringer's or choline Cl-Ringer's. To partition the routes of the conductive Cl- ion flow, we measured in the isolated epithelium with double-barrelled microelectrodes apical membrane potential. Va, and intracellular Cl- activity, acCl, of the principal cells identified by differential interference contrast microscopy. Under short-circuit conditions, Isc = 27.0 +/- 2.0 microA/cm2, with NaCl-Ringer's bathing both surfaces, Va was -67.9 +/- 3.8 mV (mean +/- SE, n = 24, six preparations) and acCl was 18.0 +/- 0.9 mM in skins from animals adapted to distilled water. Both Va and acCl were found to be positively correlated with Isc (r = 0.66 and r = 0.70, respectively). In eight epithelia from animals adapted to dry milieu/tap water Va and acCl were measured with KCl Ringer's on the outside during activation and deactivation of the transepithelial Cl- conductance (GCl) by voltage clamping the transepithelial potential (V) at 40 mV (mucosa positive) and -100 mV. At V = 40 mV; i.e. when GCl was deactivated, Va was -70.1 +/- 5.0 mV (n = 15, eight preparations) and acCl was 40.0 +/- 3.8 mM. The fractional apical membrane resistance (fRa) was 0.69 +/- 0.03. Clamping to V = -100 mV led to an instantaneous change of Va to 31.3 +/- 5.6 mV (cell interior positive with respect to the mucosal bath), whereas neither acCl nor fRa changed significantly within a 2 to 5-min period during which GCl increased by 1.19 +/- 0.10 mS/cm2. When V was stepped back to 40 mV, Va instantaneously shifted to -67.8 +/- 3.9 mV while acCl and fRa remained constant during deactivation of GCl. Similar results were obtained in epithelia impaled from the serosal side. In 12 skins from animals adapted to either tap water or distilled water the density of mitochondria-rich (DMRC) cells was estimated and correlated with the Cl current (ICl through the fully activated (V = -100 mV) Cl conductance). A highly significant correlation ws revealed (r = -0.96) with a slope of -2.6 nA/m.r. (mitochondria-rich cell and an I-axis intercept not significantly different from zero.(ABSTRACT TRUNCATED AT 400 WORDS)

Amiloride↗

PubMed1978

Studies on the etiology of the experimental neuropathy from industrial adhesive (glues).

Chickens treated by paintbrushing with glue distillate (used in shoe industries), hydrocarbon mixture and TOCP in hexane, developed paralysis (4/5); in these, we have demonstrated a diffuse degeneration of the myelinic sheath of the peripheral and central neurites. Besides TOCP, cyclohexane (because of its higher concentration in the glue distillate and in the hydrocarbon mixture) may be indicated as responsible for occupational neuropathy.

Adhesives↗

PubMed1996

Identifying the sex of human preimplantation embryos in X-linked disease: amplification efficiency of a Y-specific alphoid repeat from single blastomeres with two lysis protocols.

INTRODUCTION: Preimplantation diagnosis involves detecting genetic defects in one or two blastomeres biopsied from cleavage stage embryos following a vitro fertilization (IVF). For X-linked recessive disease, identification of the sex of embryos allows transfer of only unaffected females. To examine how critical the preparation of the single blastomere is for amplification of a Y chromosome specific repeat sequence using the polymerase chain reaction (PCR), the incidence of amplification failure has been examined following two lysis protocols. MATERIALS AND METHODS: Amplification of a Y alphoid repeat sequence from single blastomeres disaggregated from cleavage stage embryos was examined after either (1) lysis in distilled water and freeze-thawing twice or (2) a two-step lysis protocol involving an initial treatment in potassium hydroxide and dithiothreitol. Some of the embryos had been previously sexed by cleavage-stage biopsy and fluorescent in situ hybridization with X- and Y-specific probes. RESULTS: Amplification failure occurred in 6 of 50 (12%) and 4 of 60 (7%) single blastomeres from male embryos following lysis in distilled water or using the two-step protocol, respectively. Conversely, amplification from contaminating DNA occurred in 5 of 63 (8%) single blastomeres from female embryos and 6 of 94 (6%) of control medium-blanks. CONCLUSIONS: The incidence of amplification failure was improved but not eliminated using the two-step lysis protocol. At least two cells, therefore, would be necessary for accurate identification of males by amplification of Y-specific repeat sequences alone. Nevertheless, this protocol for preparing cleavage-stage blastomeres is likely to give more consistent amplification of any unique or repeat sequences.

Blastomeres↗

PubMed1987

Effects of imidazole and some imidazole-derivatives on lisuride-induced mounting and aggressiveness.

Adult male rats were treated intraperitoneally (IP) with imidazole (IMID), distilled water or saline prior to administration of lisuride either IP or intracerebroventricularly (ICV) at doses too low by themselves to elicit the behavioural signs of mounting and aggressiveness, typically induced by higher doses of this drug. Pretreatment with distilled water or saline, or the procedure of injection alone, stimulated mounting in some of the animals. At a certain range of doses IMID induced a marked increase in both mounting and aggressive posturing in the same animals, while at higher doses mounting ceased, violent aggressive behaviour appeared and some of the rats died. Seven IMID derivatives were used on the lisuride-test: N-methylimidazole, 2-methylimidazole, 4-methylimidazole, N-acetylimidazole, 4-imidaaoleacetic acid, clonidine and cimetidine. Only 4-imidazoleacetic acid was completely ineffective with respect to controls. All the other drugs enhanced aggressive behaviour to varying degrees but proved to be less potent than IMID in inducing mounting, and clonidine reduced mounting at all the doses tested.

Aggression↗

PubMed1981

Effects of proteolytic enzymes on vitamin B12 uptake by rat intestinal mucosa homogenates and of proteolytic enzymes and anti-rat intrinsic factor antibodies on vitamin B12 absorption in total gastrectomized rats.

Trypsin inhibited 57CoB12-rat IF uptake by rat small intestinal mucosa homogenates in vitro. This tryptic inhibition was inactivated by rat serum and normal human serum, as well as soybean trypsin inhibitor (STI). The effects of trypsin dissolved in distilled water or 0.0025 N HCl, 0.15 M saline extract of rat pancreas and STI on vitamin B12 absorption were studied in vivo, using gastrectomized rats. IF-mediated B12 absorption was significantly decreased by 5 mg of trypsin dissolved either in distilled water or 0.0025 N HCl. However, the inhibition of trypsin was much more remarkable when it was dissolved in 0.0025 N HCl, whereas B12 absorption was insignificantly decreased by administering 10 mg of trypsin dissolved in 0.0025 N HCl. The possibilities of this phenomenon was discussed. The inhibitory effect of 0.5 ml of 0.15 M saline extract of rat pancreas was investigated as well. Soybean trypsin inhibition showed no effect on B12 absorption when it was given with 57CoB12-rat IF at the same time. However, the B12 absorption was significantly increased when STI was given one hour prior to the administration of 57CoB12-rat IF. This suggested that endogenous trypsin bound to rat small intestine had been inactivated and pancreatic secretion had been stimulated by STI. IF-mediated B12 absorption was diminished to almost the same level of 57CoB12 administration alone by simultaneous intubation of both 57CoB12-rat IF and rabbit anti-rat IF serum in total gastrectomized rats.

Animals↗

PubMed1982

Buffering capacity of the chief components of nutritive media for algae.

The buffering capacity of solutions of KH2PO4 and NaHCO3 increases with their concentration, the behaviour being describable by mathematical expressions. Solutions of KH2PO4 prepared from tap water exhibit a buffering capacity higher by an order of magnitude than those prepared from distilled water. However, there is no difference between the buffering capacities of solutions of NaHCO3 prepared from tap and distilled water. Urea and NH4NO3 have almost no effect on the buffering capacities of solutions.

Bicarbonates↗

PubMed1991

Apparent risk factors for chronic and acute pancreatitis in Stockholm county. Spirits but not wine and beer.

In Stockholm county, the incidences of hospitalizations for chronic pancreatitis, acute, nongallstone associated pancreatitis, and alcoholic liver disease peaked at 14.1, 40.1, and 24.3/100,000 population in 1974 for the first two conditions, and in 1979 for the last one. After the peaks, a steady decline was seen for each condition. Furthermore, the apparent national and Stockholm prevalence of chronic pancreatitis displayed a decline during 1971-1987. A concomitant decline in the Stockholm sales figures of distilled spirits from 9.2 to 5.4 1/person/yr was also observed, whereas the sales figures for wine and beer increased, leaving the overall alcohol purchase unchanged. Thus, the consumption of distilled spirits, but not that of wine and beer, appear as a risk factor for these diseases in Stockholm county.

Acute Disease↗