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PubMed2001

The effect of a dental unit waterline treatment regimen on the shear bond strength of resin-based composite.

BACKGROUND: Numerous methods of disinfecting dental waterlines have been suggested. This study evaluates the effects of one disinfecting technique on the strength of resin-based composite's bond to enamel and to dentin. METHODS: The authors bonded resin-based composite cylinders to enamel and dentin surfaces similarly mounted and prepared using three irrigation solutions. After undergoing acid etching, the tooth surface was rinsed with either distilled water, water from a municipal water source or a mixture of distilled water and mouthwash concentrate. The authors shear-tested the samples and analyzed the data statistically. RESULTS: The group rinsed with distilled water mixed with mouthwash exhibited the lowest shear bond strengths. However, a one-way ANOVA indicated no statistically significant differences in the mean values among the treatment groups for either enamel (P = .295) or dentin (P = .393). Specimens bonded to enamel demonstrated primarily adhesive fracture at the tooth/composite interface. Those bonded to dentin showed a similar pattern, with some sites of cohesive fracture in the resin-based composite. CONCLUSIONS: There was no significant difference in shear bond strengths of resin-based composite to tooth structure when rinsed with distilled water mixed with mouthwash, distilled water or water from a municipal source. CLINICAL IMPLICATIONS: Dental unit waterlines disinfected using a diluted mouthwash solution may be used while bonding resin-based composite to either enamel or dentin.

Acid Etching, Dental↗

PubMed2000

Media, product differences and seasonality in alcohol advertising in 1997.

OBJECTIVE: To spell out recent events related to the alcohol advertising controversy and to describe the extent of alcohol advertising for 1 year, the media favored for advertising different types of alcoholic beverages and seasonal variation in advertising patterns. METHOD: Monthly advertising data for 1997 were obtained from a variety of sources, including a commercial media monitoring service, a watchdog group, and trade and business press. Media examined were national and local television, radio, magazines, newspapers and billboards. RESULTS: Alcohol advertising expenditures were greatest in the late spring/early summer and during the holiday season. Television received the preponderance of alcohol advertising dollars for beer, wine, wine coolers and premixed drinks. Distilled spirits relied mostly on magazine advertising. Beer was the most heavily advertised product. More than half of televised beer ads aired on Saturday or Sunday afternoon during sporting events. There were more radio and TV ads for premixed low-alcohol beverages--some of which contain distilled spirits and many using brand names of distilled spirits--than for higher proof distilled spirits. CONCLUSIONS: Public health officials can use the results to plan the month and media in which to launch messages against alcohol misuse, to directly counter pro-alcohol messages in advertising. They should monitor consumption and advertising of premixed beverages. Those concerned with the debate on alcohol advertising should note the access children have to beer ads when these ads are aired during weekend daytime sporting events, and that beer remains the greatest advertised beverage, despite the 1996 lifting of the broadcast advertising ban on distilled spirits.

Advertising↗

PubMed1998

Degradative changes in whole enamel homogenates incubated in vitro in the presence of low calcium ion concentrations.

The purpose of this study was to investigate overall degradative changes occurring to enamel matrix proteins in small, freeze-dried pieces of rat incisor enamel homogenized and incubated directly for 0-48 hours in a synthetic enamel fluid solution (165 mM total ionic strength with 0.153 mM calcium chloride) versus other samples homogenized and incubated for the same time intervals in distilled water. The results indicated that many alterations in the apparent molecular weights of enamel matrix proteins took place under both conditions although the rates for many degradative changes over a 48 hour period were often slower in distilled water than in synthetic enamel fluid. Freeze-dried enamel samples homogenized and incubated in 165 mM Tris-HCl buffer at pH 8.0 showed changes comparable to those seen with distilled water. This suggested that differences observed between samples incubated in enamel fluid versus distilled water were unrelated to pH or ionic strength of the solutions and may be the result of a requirement by some enamel proteinases for small amounts of free calcium ions in incubation media. Of interest were findings that some enamel matrix proteins, especially those in strips taken from the first half of the secretory stage of amelogenesis, were degraded much faster in distilled water than in synthetic enamel fluid. The reasons for this effect are unclear although, in this case, calcium ions could be inhibitory to hydrolysis of certain matrix proteins by the enamel proteinases.

Animals↗

PubMed1978

Myelin impregnation: an improved Golgi-Cox modification.

Optic tecta of goldfish were coated with egg yolk and immersed for only one week in one of the following impregnation fluids: a) Solution A + B; A = 1 g K2Cr2O7 and 1 g HgCl2 boiled for 15 min in 85 ml distilled water and allowed to cool; B = 0.8 g K2Cr2O4 and 0.5 g KWO4 dissolved in 20 ml distilled water. b) Solution A + B two volumes diluted with boiled distilled water. c) Solution A + B four volumes diluted with boiled distilled water. Each tectum was immersed 6 hr in 100 ml distilled water containing 0.5 g LiOH and 15 g KNO3, washed 18 hr in 500 ml 0.2% acetic acid, dehydrated with ethanol, and embedded in low viscosity nitro cellulose. Sections were cut at 100 micron with a rotary microtome after clearing with cedarwood oil. Methods b) and c) have two advantages compared with method a), the original Golgi-Cox method. First, more cells are impregnated, especially in the layers extending 200-400 micron below the surface, and dendrites as well as unmyelinated axons are well impregnated. Second, myelin sheaths are impregnated and can be recognized by their peculiar chain-like appearance. The described Golgi-Cox modification offers an appropriate method to study the morphology of superficially located nervous tissue.

Animals↗

PubMed1999

Ablation of vitreous tissue with erbium:YAG laser.

PURPOSE: Using a noncontact erbium (Er):yttrium--aluminium--garnet (YAG) laser, ablation of vitreous was compared to distilled water in vitro. METHODS: The porcine vitreous body and distilled water were ablated in vitro at different pulse lengths and pulse energies. Selected pulse energies were 25, 35, 45, 75, and 100 mJ (pulse rate: 1 Hz; laser beam diameter at the surface of the sample: 2 mm). Pulse lengths were at 140 +/- 3 microsec, 190 +/- 4 microsec, and 240 +/- 5 microsec. The loss of weight in vitreous tissue and distilled water was measured using precision scales and corrected for evaporation, respectively. The Mann-Whitney U test was used to assess the significance of differences in ablation rates of water and vitreous. P < 0.05 was considered statistically significant. RESULTS: Reproducible and constant ablation rates were found in both vitreous and distilled water in each of 10 consecutive series of 50 laser pulses at constant laser parameters. Ablation rates per pulse (microg/microsec) of vitreous tissue were as follows: 3.0 microg to 45.8 microg (140 microsec), 10.4 microg to 53.8 microg (190 microsec), and 17.9 microg to 24.2 microg (240 microsec). The ablation rates exhibited a linear correlation with increasing pulse energies and also with decreasing pulse lengths. Considering the pulse lengths of 190 microsec and 240 microsec with all pulse energies tested, the ablation rates of distilled water were significantly higher (P < 0.05) than ablation of vitreous tissue. The ablation rates at a pulse length of 140 microsec were not significantly different. The differences per pulse were as follows: 0.5 microg to 2.1 microg (140 microsec), 1.9 microg to 6.0 microg (190 microsec), and 3.5 microg to 8.7 microg (240 microsec). CONCLUSIONS: Vitreous ablation is possible using Er:YAG laser. The ablation characteristics of vitreous have proved to be similar but not equal to that of water.

Animals↗

PubMed2004

In vitro buffering properties of 3 composite resins.

AIM: A dental composite resin, Ariston pHc, has been described as having a cariostatic effect by buffering acid saliva and preventing decalcification and infiltration of restorations. The buffering effect has been reported due to the release of OH- originated from the alkaline glass embedded in the resin. The release would occur only in the presence of low salivary pH values. The aim of this in vitro investigation was to evaluate pH variations induced by Ariston pHc and 2 other composite resins (P60 and Z100). METHODS: Eighteen samples were prepared for each composite and 5 specimens of each brand were embedded in artificial saliva according to Brugirar and Mazille, at 3 different pH values. A 1(st) group of 5 specimens of each tested resin was immersed in neutral artificial saliva at pH 7.7, a 2(nd) group in acidified artificial saliva at pH 5.45 and a 3(rd) group in alkalised saliva at pH 9.25. Three other samples of each resin were immersed in tubes containing distilled water at pH 7.23 and served as controls. Twelve tubes were filled only with neutral, alkalised and acidified artificial saliva and distilled water at the above mentioned pH values. Measurements of pH modifications were taken after 1, 3, 9, 14, 31 days. RESULTS. Ariston pHc raised the pH of distilled water up to 9.59 after 1 day, and to 8.42 after 31 days. This pH modification shown by Ariston pHc in distilled water, compared to those of the other 2 composites were statistically highly significant, with p<0.001, while the pH variations of saliva containing the 3 resins were negligible, except for acidified saliva with Ariston pHc, where a slight pH enhancement with some statistical significance (p=0.04) was found. However, acidified saliva without any resin embedded was found to shift to neutrality as well. CONCLUSION: These results strongly suggest that none of the 3 tested materials can achieve an effective buffering action in vitro on low salivary pH values. However, the ability of Ariston pHc to raise the pH in distilled water, and to a lesser degree in acidified saliva, suggests that an in vivo buffering effect cannot be excluded.

Buffers↗

PubMed2006

Punica granatum (pomegranate) extract is active against dental plaque.

In the present work, we studied the effect of the hydroalcoholic extract (HAE) from Punica granatum (pomegranate) fruits on dental plaque microorganisms. The study was conducted on 60 healthy patients (33 females and 27 males, with age ranging from 9 to 25 years) using fixed orthodontic appliances, and randomly distributed into 3 groups of 20 patients each. The first group (control) used distilled water, while the second and third groups used chlorhexidine (standard) and HAE as mouth-rinses, respectively. The dental plaque material was collected from each patient, before and after a 1-min mouth-rinse with 15 ml of either distilled water, chlorhexidine or HAE. In both dental plaque collections, the material was removed from patients without oral hygiene, for 24 h (no tooth brushing). Dental plaque samples were diluted in phosphate buffered saline (PBS) plated on Mueller-Hinton agar, and incubated for 48 h, at 37 degrees C. Results, expressed as the number of colony forming units per milliliter (CFU/mL), show that the HAE was very effective against dental plaque microorganisms, decreasing the CFU/ml by 84% (CFU x 10(5)), before mouth-rinse: 154.0 +/- 41.18; after mouthrinse: 25.4 +/- 7.76). While similar values were observed with chlorhexidine, used as standard and positive control (79% inhibition), only an 11% inhibition of CFU/ml was demonstrated in the distilled water group, negative control (CFU x 10(5)), before mouth-rinse: chlorhexidine, 208.7 +/- 58.81 and distilled water, 81.1 +/- 10.12; after mouth-rinse: chlorhexidine, 44.0 +/- 15.85 and distilled water, 71.9 +/- 8.68). The HAE presented also an antibacterial activity against selected microorganisms, and may be a possible alternative for the treatment of dental plaque bacteria.

Adolescent↗

PubMed1990

An improved method of mass culturing of Romanomermis iyengari, a mermithid nematode parasite of mosquito larvae.

An attempt was made to develop an alternative method of mass culturing for R. iyengari instead of the usual sand culture method. Fifty pairs each of post-parasitic juveniles were seeded in moist sandbed and beakers containing tap water and distilled water and examined for exsheathing, egg-laying and egg-hatching. All post-parasitic juveniles in the moist sandbed had moulted by 7th day whereas in tap water and distilled water it lasted up to 11th day. Maximum numbers of eggs were observed on day 14 in sandbed (15/ml), day 16 in tap water (24/ml) and day 29 in distilled water (28/ml). The preparasites obtained from moist sandbed, tap water and distilled water did not exhibit any difference in their infectivity to mosquito larvae. The eggs of the nematode obtained from a culture in distilled water maintained at 30 +/- 2 degrees C for 60 days, when treated with CO2 (18 to 556 ppm) showed enhanced rate of egg hatching (73-98% compared with 11.5% in the untreated ones). CO2 treatment did not affect the infectivity of the preparasites that hatched from the CO2-treated eggs.

Animals↗

PubMed1982

The influence of ascorbic acid on survival of mice following whole body X-irradiation.

Two strains of mice (Swiss and CF1), male and female, were used in this study. The mice drank either distilled water or 0.1% ascorbic acid in distilled water for one week prior to and during the experiments. Mice were irradiated in groups of 10; they received total body X-irradiation in a single exposure ranging from 200 R to 750 R. Time of death was recorded daily while weight changes and volume of water consumed were recorded every other day. At the low exposure levels, our results indicated that: a) mice drinking ascorbic acid in distilled water died about one week earlier than those drinking distilled water only, and b) the LD 50/30 was higher in mice drinking only distilled water. The differences between both groups were noticeable at exposures up to 550 R; at higher exposures, there was no difference. This study showed that high levels of ascorbic acid potentiated the effect of X-ray whole body irradiation.

Animals↗

PubMed1988

New technique for differential staining of myelinated fibers and nerve cells on paraffin sections.

A simple, rapid method for the differential staining of myelinated nerve fibers and nerve cell bodies, applicable to sections of central nervous system pieces embedded in paraffin, is described. Experimental material fixed by perfusion with mixed aldehydes or necropsy material fixed in formaldehyde can be used. Constant and homogeneous results are obtained with this technique, and the most important characteristic is the absence of differentiation in either of the steps: staining of myelinated fibers and staining of nerve cell bodies. Sections 15 microns thick were attached to slides, dewaxed, and hydrated. After hydration, sections are mordanted (30 min) in 2.5% iron alum (SO4)2FeNH4, and rinsed (1 min) in distilled water. Staining is for 180 min in the following solution: 5 ml freshly made 20% alcoholic hematoxylin diluted with 25 ml of distilled water and 25 ml of absolute ethanol to which 10 ml of 1% Li2CO3 is added. The sections are washed in distilled water (5 min) and stained during 5 min in the following solution: 0.2% pyronine, 20% formaldehyde in distilled water. The sections are dehydrated through 96% and absolute ethanol, cleared in eucalyptol, and mounted in Eukitt. Myelinated fibers appear dark blue, whereas nerve cell bodies are stained red and the cell nucleoli dark blue. This procedure provides an adequate contrast for observation and photography.

Animals↗

PubMed1995

Viscoelastic properties of human tracheobronchial mucin in aqueous solution.

Human tracheobronchial mucin isolated from cystic fibrosis patients (CF HTBM) was purified using a combination of gel filtration and density gradient centrifugation. The resulting mucin was fractionated to reduce polydispersity and to facilitate studies of the molecular weight dependence of mucin viscoelasticity in concentrated solution. The viscoelastic properties of CF HTBM were examined in distilled water, 0.1M salt solutions and chaotropic solvents. In controlled strain experiments (strain > or = 5%) with increasing mucin concentration, a crossover from sol to gel behavior is observed. The gel strength, as measured by the magnitude of the storage modulus at comparable mucin concentrations, is greatest for distilled water, intermediate for 0.1M NaCl, and lowest for 6M GdnHCl. In distilled water, high molecular weight mucin undergoes a sol-gel transition at approximately 12 mg/mL, and shows evidence of a plateau modulus at higher concentrations. The storage and loss moduli of concentrated high molecular weight fractions in 6M GdnHCl exhibit a power law dependence on frequency typical of weak gels near the sol-gel transition at 20 mg/mL. Similar rheology is observed in 0.1M NaCl and 0.091M NaCl/3 mM CaCl2, but with evidence for additional weak associations at low frequency. The power law exponent in these systems is 0.70 +/- 0.02, in good agreement with prediction for networks formed by a percolation mechanism. Low molecular weight fractions in these solvents exhibit a fluid-like viscoelastic response. However, low molecular weight mucin in distilled water shows a strain-dependent increase in elasticity at low frequency indicative of weak intermolecular associations. Comparison of the rheological behavior of CF HTBM with our earlier studies of ovine submaxillary mucin lends support to the idea that carbohydrate side-chain interactions are important in the gelation mechanism of mucins.

Bronchi↗

PubMed1977

Study on the chemical nature of sterols contained in Bulgarian sunflower oil.

The free sterols, the sterol esters and the sterol glycosides of the crude sunflower oil as well as those of the technical lecithin, the pitch and the deodorizer distillate of the latter oil were isolated by preparative TLC. The nature of sterols contained in the isolated sterol derivatives was elucidated by GLC and combinded GLC-MS. Major sterols of all examined sterol fractions are sitosterol, campesterol and stigmasterol, the amount of sitosterol being prevalent. Unknown sterol with a molecular weight of 428 is present in sterols of the crude oil and the deodorizer distillate. Sterols of the deodorizer distillate contain an unknown sterol with a molecular weight of 430. Stigmasterol is present in the sterol fraction of the deodorizer distillate in high amounts. It was established that delta7-sterols of the crude oil occur only in esterified form. The hydrolysis of the sterol derivatives in acid medium leads to dehydration products known as steroid dienes and disteroid ethers. Hydrolysis without dehydration was achieved by enzyme preparations. Some sterols of the crude oil were esterified with the same higher fatty acids contained in the glycerides of the sunflower oil.

Chromatography, Gas↗

PubMed1983

Initiation/promotion studies with coal-derived liquids.

Fractions derived from solvent-refined coal-II (SRC-II) heavy distillate (HD) were tested for their skin tumor initiating activity. Basic (BF), basic tar (BTF), neutral tar (NTF) and polynuclear aromatic (PNA) fractions were prepared from HD by solvent extraction. These fractions were tested for their initiating activities by applying a single dose to the shaved back of male, CD-1 mice (Charles River, Portage, MI). Positive control groups were initiated with either dimethylbenz[a]anthracene (DMBA) or benzo[a]pyrene (BaP). Two weeks after initiation, all mice received twice weekly applications of 5 micrograms of phorbol myristate acetate (PMA) for a period of 24 weeks. Papillomas were noted and recorded for each animal at the time of PMA application. Heavy distillate and its fractions all showed initiating activity. However, the incidence of mice with tumors, the rate of tumor appearance and the total number of tumors varied with the test material. The tumor responses after initiation with HD,NTF and BTF were similar to that found with BaP, but lower than that with DMBA. Somewhat lower activity was found for BF and PNA. Even lower activity was found with a distillate boiling from 800 to 850 degrees F and no activity was found with a 300 to 700 degrees F distillate. These data are in general agreement with the results of long-term, skin painting assays, suggesting that initiation/promotion (I/P) may be useful for studying the tumorigenicity of coal-derived materials.

9,10-Dimethyl-1,2-benzanthracene↗

PubMedDate not supplied

Jet nebulization of PEI/DNA polyplexes: physical stability and in vitro gene delivery efficiency.

BACKGROUND: Aerosol drug delivery currently represents the most acceptable and convenient delivery system for repeated drug application to the lungs. Although polyethyleneimine (PEI) has recently been demonstrated to mediate gene transfer successfully to mouse lungs via aerosol delivery, the effect of the jet nebulization process on the properties of PEI/DNA polyplexes has not yet been examined. METHODS: PEI/DNA polyplexes were generated in several commonly used solvents, such as distilled water, HEPES buffered saline (HBS), and 5% glucose. The complex parameters, such as particle size, zeta potential, DNA integrity, and transfection efficiency, were examined before and after jet nebulization. RESULTS: The complex parameters and the transfection efficiency were influenced by the solvent that was used for complex formulation and by the nebulization process itself. When polyplexes were formulated in HBS, the particle size, zeta potential, and DNA concentration were affected by the nebulization process and the transfection efficiency decreased dramatically. Polyplexes formulated in 5% glucose were less susceptible to the nebulization process, as indicated by only minor changes of the zeta potential and particle size when compared with HBS. The resulting transfecion efficiency was very low both before and after nebulization. Polyplexes formulated in distilled water had the most resistant behavior with the nebulization process. Zeta potential, particle size, and DNA integrity were influenced least of all by nebulization. CONCLUSION: As a result, the transfection efficiency of PEI/DNA complexes remained constant throughout the nebulization process only when formulated in distilled water. These data suggest that distilled water represents the most appropriate solvent for polyplex formulation when delivered by jet nebulization.

Animals↗

PubMed2007

A faster plant stem-water extraction method.

Oxygen and hydrogen isotope ratios of stem water have been used by several studies which relate the ecophysiology of plants to their water source. Undoubtedly, there are several other applications and research areas which could use this type of analysis. However, the most often used methods of extracting stem water are slow, limiting the rate of sampling and consequently preventing a deeper understanding of spatial and temporal plant water source use. We have developed a faster batch method of stem-water extraction and compare it with the most commonly used online method of stem-water extraction. Samples are sealed in 18 cm long ampoules having their extremities placed sample end in a heating block and the condensing end in a cooling block, and allowed to distill overnight. Up to 72 samples can be distilled overnight and sealed the next morning. The isotope ratios of water distilled by the batch method introduced here compared with those from the online method were in excellent agreement. In addition to being faster, this method does not need the monitoring of hot water baths and liquid nitrogen traps during distillation and does not require a complex vacuum system.

Chemistry Techniques, Analytical↗

PubMed2000

Effects of male rat urine on reproductive and developmental parameters in the dam and her female offspring.

This study investigated the direct and indirect effects of male Norway rat (Rattus norvegicus) urine on reproductive, developmental, and fecundity parameters in the dam and her female offspring. Twenty-two dams and litters were studied: 11 in male urine and 11 in distilled water conditions. Only dams were exposed to male urine (or distilled water) from days 14 to 29 postpartum. Significant effects found for the dams exposed to male urine (compared to those only exposed to distilled water) included (i) the second lactational estrus was delayed by 2 days, (ii) vaginal opening and first estrus were 1 day later for female offspring, (iii) the first estrous cycle after vaginal opening was also shorter for their offspring, and (iv) female offspring subsequently produced larger litters than female offspring from dams only exposed to distilled water. Thus, urine from males had direct effects on the timing of the second lactational estrus in dams and indirect effects (mediated by the dam) on developmental and reproductive parameters of her female offspring. Taken as a whole, these results suggest that pheromones in Norway rats may be complex in their effects, context-dependent, and only fully revealed in ecologically relevant contexts. Further study is required to determine whether these effects occur and have biological functions in natural populations.

Animals↗

PubMed2001

Hippocampal injections of amyloid beta-peptide 1-40 impair subsequent one-trial/day reward learning.

The injection of amyloid beta-peptide (Abeta) into rat CNS has been reported to induce cellular neuropathology. The present study investigated whether multiple intrahippocampal injections of Abeta 1-40 would impair one-trial/day reward learning 14 days later. Twenty-four male Sprague-Dawley rats, 3-4 months old, were injected with either Abeta 1-40 or distilled water into seven hippocampal sites bilaterally. Ten rats received 3 nmol Abeta 1-40 in 2 microl of distilled water per injection site, while 14 rats received distilled water alone. Following a 9-day recovery period, rats were gradually food deprived to 82% of their initial body weight. Fourteen days after the intrahippocampal injection, all rats received an initial training trial and three subsequent daily retention trials. Rats receiving Abeta 1-40 were significantly impaired on the second retention trial in terms of accuracy (number of unbaited alleys entered) and on the second and third retention trials in terms of speed (reciprocal of latency to reward). Histological analysis showed that Abeta 1-40 injections produced significant neuronal loss and gliosis. Abeta 1-40 immunoreactivity persisted locally at the injection site and in macrophages 2 weeks following the hippocampal injections. These effects appear to be sequence-specific; rats receiving Abeta 1-42 with a scrambled peptide sequence did not differ significantly from rats receiving distilled water alone in retention of the learning task or degree of histological damage.

Alzheimer Disease↗

PubMed1987

Short-acting novel MAO inhibitors: in vitro evidence for the reversibility of MAO inhibition by moclobemide and Ro 16-6491.

The inhibition of monoamine oxidase (MAO) in rat liver and brain by the short-acting MAO-A inhibitors moclobemide (Ro 11-1163 = p-chloro-N-[2-morpholinoethyl]benzamide) and brofaremine and by the short-acting MAO-B inhibitors Ro 16-6491 (N-[2-aminoethyl]-p-chloro-benzamide) and almoxatone, administered p.o. at roughly equieffective doses 2 h before decapitation, was investigated for its reversibility under various in vitro conditions. MAO A activity in liver homogenates, inhibited by moclobemide (300 mumol/kg) to approx. 15% of control, time dependently recovered during 0.5 to 2 h of incubation at 37 degrees C, irrespective of whether the homogenates were prepared and incubated in distilled water or Krebs-Ringer buffer (KRB). Dialysis of such homogenates for 4 h in distilled water at 37 degrees C (but not at 13 degrees C) led to a complete return of the MAO activity. In liver homogenates from rats pretreated with brofaremine (30 mumol/kg), dialysis for 4 h at 37 degrees C against distilled water caused only little recovery of the MAO activity. Likewise, MAO-B inhibited by Ro 16-6491 (30 mumol/kg) to approx. 4% of control returned to almost control activity after 4 h of dialysis at 37 degrees C, while inhibition induced by almoxatone (30 mumol/kg) was little or not reversed at all. In brain homogenates prepared in, and dialysed against, distilled water or KRB at 37 degrees C (but not at 13 degrees C), MAO-A inhibited by moclobemide (100-300 mumol/kg) to approx. 15% of control, partially (KRB) or almost completely (dist. water) returned to control activity after 4 h of dialysis.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗