The effect of testosterone propionate on growth of broiler chickens.

The effects of testosterone propionate (TP) on body weight, tissue percentages of body weight, serum IgM, and rectal temperature (2 h postinjection) of male and female broiler chickens were investigated at 28 and 48 days posthatching. Testosterone propionate was dissolved in sesame oil and was injected at 2 mg/kg of body weight every other day, and controls were treated with sesame oil at similar volume, starting Day 7 posthatching. Administration of TP reduced (P < .05) body weight and percentages of liver, testes, and bursa of Fabricius at 28 and 48 days of age. At 28 and 48 days of age, muscle percentage and comb growth of TP-treated birds increased (P < .05) but ovarian weight was unaffected. Concentrations of IgM in serum of TP-injected birds was unchanged at Day 28, but increased (P < .05) at Day 48. Testosterone propionate did not affect percentages of bone or abdominal fat in either sex. Rectal temperature was depressed (P < .05) by TP treatment in both sexes at both ages.


Cross-reactivity of sperm-binding proteins from chicken, turkey, and duck oocytes.

Binding and penetration of spermatozoa through the perivitelline layer (PL) overlying the hen's ovum have been studied more frequently in the chicken than in other domesticated avian species. Species-specific action of the binding process was tested using an in vitro competition assay in which spermatozoa from the cock, tom, and drake were pretreated with solubilized PL protein (PL-P) from the chicken, turkey, and duck ovum. Spermatozoa were pretreated with PL-P for 20 min at 39 C and co-incubated in vitro with a .5 cm2 section of intact PL from the homologous sperm donor species for an additional 10 min at 39 C. Effectiveness of PL-P pretreatment was assessed quantitatively by the number of spermatozoa bound to the PL, and was expressed as a percentage of the control [minimum essential medium (MEM) pretreated sperm = 100%] binding. Pretreatment of cock spermatozoa with chicken, turkey, or duck PL-P resulted in 21, 40, and 48% binding, respectively. Similarly, pretreatment of tom spermatozoa with PL-P from chicken, turkey, or duck resulted in 45, 51, and 39% binding, and that of drake spermatozoa resulted in 38, 32, and 21% binding, respectively. Incubation of spermatozoa with PL-P from chicken, turkey, and duck ova indicated cross-reactivity and suppression of binding between avian spermatozoa and PL that was not species-specific.


Sex differences in incubation length and hatching weights of broiler chicks.

Two experiments were run using broiler eggs (Peterson x Arbor Acres) to determine whether sex differences exist in incubation time required to hatch males and females and in various measures of chick weight (CW). Relationships between measures of CW and incubation time and between CW and egg weight (EW) were determined. Chicks that had emerged from eggs were removed from the hatcher at approximately 6- (5 to 8) h intervals between 490.5 and 527.5 h of incubation in Experiment 1 and at about 2-h intervals between 483 and 524 h of incubation in Experiment 2. Chicks were weighed before and after removal of the residual yolk sac immediately upon removal from the hatcher. In both experiments, a preponderance of early-hatching chicks were female. The time at which 50% of the females had hatched was significantly (P = .05) earlier than the 50% hatch time for males (2.68 and 3.32 h in Experiments 1 and 2, respectively). About 71% of the females had hatched by 504 and 509 h in Experiments 1 and 2, whereas only 57 and 52% of the males had hatched at comparable times. In Experiment 2, the yolk-free CW (YFCW) of males tended to be greater than that of females (P = .07) and the YFCW expressed as a percentage of EW was significantly (P = .007) greater. The regression of CW and YFCW on EW were highly significant and positive in both experiments. There was a significant relationship between EW and time required to hatch for males in Experiment 1 only.


Analysis of the combined effect of the spermatozoal degeneration allele (Sd) and homozygosity of the rose comb allele (R) on the duration of fertility of roosters (Gallus domesticus).

Roosters homozygous for the rose comb allele (R/R) are subfertile. Likewise, roosters bearing the dominant spermatozoal degeneration allele (Sd) are subfertile. The objective of the present research was to see whether these effects were cumulative. Domestic fowl were bred in order to obtain males representing the following genotypes: R/r+ sd+/sd+, R/r+ Sd/sd+, R/R sd+/sd+, and R/R Sd/sd+. Duplicate fertility trials were conducted with Single Comb White Leghorn hens. In each trial, ejaculates were pooled according to genotype. The insemination dose was 1 x 10(8) viable spermatozoa per hen, and eggs were collected over a 21-day interval following a single intravaginal insemination. Fertility over the 21-day period was 53 +/- 2.1 (SEM), 36 +/- 1.6, 21 +/- 2.1, and 11 +/- 1.2%, respectively. Therefore, the effect of homozygosity for the R allele and the presence of the Sd allele were cumulative in the depression of fertility.


Research note: effect of in ovo 17-beta-estradiol or tamoxifen administration on sexual differentiation of the external genitalia.

The effect of in ovo administration of tamoxifen or 17 beta-estradiol on external sexual dimorphism in chickens was investigated. In two trials, fertile eggs were injected with either tamoxifen (200 micrograms per egg) or vehicle (100 microL corn oil) on Day 1 of incubation, or with 17 beta-estradiol (20 micrograms per egg) or vehicle on Day 11 of incubation. Sexes were determined by visual inspection of the external genitalia and by gonadal identification at Day 1 posthatch. Tamoxifen injection resulted in a significantly greater number of phenotypic male identifications, with male:female ratios of 76:24 (Trial 1) and 62:38 (Trial 2) based on external genitalia phenotype. Gonadal sexing corrected these ratios to 46:54 and 44:56, resulting in genital sexing errors of 27% (Trial 1) and 18% (Trial 2). These errors were significantly higher than genital sexing errors of the chicks treated with vehicle (2 and .6% for Trials 1 and 2, respectively). In ovo administration of 17 beta-estradiol resulted in an increased number of female identifications based on genital sex determination, with male:female ratios of 37:63 (Trial 1) and 46:54 (Trial 2). Gonadal sexing corrected these ratios to 54:46 and 51:49, resulting in genital sexing errors of 10 and 6% for Trials 1 and 2, respectively. These errors were significantly higher than genital sexing errors of vehicle-treated chicks (4 and .9% for Trials 1 and 2, respectively). The results of the present study indicate that early embryonic administration of estrogen or an estrogen antagonist alters chicken external sexual dimorphism near the time of hatch.


Research note: a lack of response to pantothenic acid supplementation to a corn and soybean meal broiler diet.

Two 21-day battery studies were conducted to determine whether a corn and soybean meal diet without pantothenic acid supplementation was adequate for growth and feed efficiency of broilers. In each experiment, 64 1-day-old broiler chicks (32 male and 32 female) were assigned to each of six dietary treatments. The basal diet was supplemented with 0, .3, .6, 2.4, 4.8, and 14.4 mg of supplemental pantothenic acid/kg of diet. Each diet in both experiments was fed to eight pens containing four females and four male day-old Arbor Acres broiler chicks. The basal diet contained 22.3% protein and 4.74 mg/kg pantothenic acid by analysis. No improvement in growth or feed efficiency was obtained from any level of pantothenic acid supplementation.


Research note: the reactivity of anti-chondroitin sulfate antibody to comb and wattle galactosaminoglycans.

The current study was undertaken to examine the reactivity of anti-chondroitin sulfate monoclonal antibody, CS-56, to the comb and wattle galactosaminoglycans containing varying proportions of L-iduronic acid. Galactosaminoglycans were isolated from mature rooster comb and wattle tissues and were separated into four fractions (I, II, III, and IV), which were precipitable with 18, 25, 40, and 50% ethanol, respectively. Each fraction was examined using an ELISA technique. The results demonstrated presence of CS-56 epitope in galactosaminoglycans from both tissues. Most (> 99%) of the epitope were found in Fractions III and IV, which were galactosaminoglycans rich in D-glucuronic acid. Fractions I and II, which were dermatan sulfates rich in L-iduronic acid, showed little or very weak antigenicities.


Research note: effects of beak trimming and genetic stock on rate of mash consumption and feeding-related behavior in egg-strain pullets.

Pullets whose beaks were trimmed once (at 9 days) and twice (at 9 days and 9 wk) were able to ingest feed, in the form of mash, more rapidly under competitive feeding conditions and at least as rapidly in the absence of competition as pullets with intact beaks. Tests of feeding rate, when pullets fed in groups, were carried out after a feed deprivation period of 7 h at ages of 10 through 16 wk. Similar tests were done at 18 wk, when pullets fed without competition. Genetic stock and age had significant effects on frequency of agonistic acts at the feeder and displacements from the feeder during 5-min tests under competitive feeding conditions. Age influenced the number of pullets feeding simultaneously and amount of feed eaten per pullet during the same feeding tests. No interactions were detected among beak treatment, stock, and age for feeding-related behaviors or rate of feed consumption during competitive feeding. In noncompetitive feeding tests, genetic stock affected feeding rate but no stock by beak treatment interaction was present.


Biosensor development.

This article reviews the recent biosensor developments for medical applications, focusing on the various biological recognition elements used in biosensors and the systems transduction mechanisms. Available instruments utilizing biosensor technology are also examined from a commercial perspective.


Tolerability of fibric acids. Comparative data and biochemical bases.

Fibric acids are an established class of drugs for the treatment of hyperlipoproteinaemias. Although they have been in use for 30 years or longer, some doubts remain as to their relative tolerability, both as a class and as single agents. Some side effects, e.g. lithogenicity, may be related to their mode of action, while others, e.g. the acute muscular syndrome, may be linked to the spatial conformation of the molecule. These disadvantages should, however, be weighed against the additional, potentially therapeutic properties shown by these compounds. In particular, effects on maturity onset diabetes and hyperuricaemia, as well as a very interesting fibrinolytic potential, have been described for some of them. A painstaking comparative analysis of the major literature data pertaining to the clinical toxicological profile of these agents allow to conclude that, while belonging to a chemical class, fibric acids show dramatic differences from one another, in terms of side effects and of additional pharmacodynamic activities. Moreover, in the case of lithogenicity for example, considerable differences exist between normo- and hyperlipidaemic subjects. Overall, newer molecules of more sophisticated design have a significantly improved tolerability profile vs the old clofibrate.


The enantiomers of the valproic acid analogue 2-n-propyl-4-pentynoic acid (4-yn-VPA): asymmetric synthesis and highly stereoselective teratogenicity in mice.

The teratogenic activities of R(+)- and S(-)-2-n-propyl-4-pentynoic acid (R and S-4-yn-VPA), the enantiomers of the highly teratogenic valproic acid (VPA) analogues (+/-)-4-yn-VPA, were investigated in mice. The enantiomers were prepared via asymmetric synthesis, each in three steps employing the chiral auxiliaries (4R,5S)-4-methyl-5-phenyl-2-oxazolidinone and S-4-benzyl-2-oxazolidinone. The determination of the absolute configurations and the optical purities is described. R(+)-4-yn-VPA contained 7%, and S(-)-4-yn-VPA 8%, of the respective antipodes. The aqueous solutions of the sodium salts of R- and S-4-yn-VPA were administered as single i.p. injections during early organogenesis in the mouse (day 8 of gestation) using the induction of exencephaly as the teratological end point. Dose/exencephaly curves indicated that S-4-yn-VPA is 7.5 times more teratogenic than its antipode, 1.9 times more teratogenic than (+/-)-4-yn-VPA and 3.9 times more teratogenic than the parent drug VPA. In contrast, the neurotoxicity (maternal toxicity) of the 4-yn-VPA enantiomers was found to be independent of the stereo-chemical configuration and lower than achieved after VPA administration. Due to its low neurotoxicity and highly stereoselective neural tube-inducing activity, S-4-yn-VPA should prove an important tool for the investigation of molecular mechanism of the teratogenic action in this class of compounds; R-4-yn-VPA could act as the negative control in these studies.


Presence of tobramycin in kidneys and placentae of Sprague-Dawley rat fetuses and newborns following in utero exposure.

The maternal-fetal transfer of tobramycin (TBM) was investigated in the rat by means of a microbiological assay, to assess the presence and amount in the kidneys and placentae of fetuses at gestational day (GD) 20, in the kidneys of newborns 6 and 11 days after the end of treatment and in the kidneys of the dams. In the qualitative assay, pregnant rats were injected i.p. with 0, 30, 60 mg/kg b.w. of TBM on GD 10-19. A group of dams treated in parallel with 30 mg/kg b.w. was utilized for a microbiological semiquantitative assay. All litters contained some fetuses showing no detectable TBM accumulation in either kidney or in placentae: at 30 mg/kg/b.w. accumulation appeared more prevalent in placenta than in the kidneys of the corresponding fetuses, as confirmed also by the semiquantitative assay. Some newborns (about 6%) of both groups showed detectable renal TBM residues on the 6th and on the 11th day after the end of treatment. The frequency of newborns showing residues was not obviously related to the dose or the day of sampling, and the concentrations of TBM found were comparable to those observed in fetuses. It is possible that they represent a particularly sensitive subgroup.


Microscopic characterization of particle size and shape: an inexpensive and versatile method.

A variety of methods exists for measuring individual particle dimensions as a means of characterizing particle size, size distribution, and shape. The equipment described in this report belongs to the class of semiautomatic non-TV-interfaced analyzers. Unlike many existing image analysis systems, three-dimensional form measurements and texture data for the calculation of particle size and shape parameters can be determined easily and directly from each particle profile using this system. Essentially all data are collected directly from the particle and recorded by the computer with no intermediate steps. Much of the system consists of general-purpose and relatively inexpensive, commercially available hardware and software. Using this method, particle size, size distribution, and qualitative or quantitative shape information can easily and rapidly be obtained simultaneously. Particle length and width characterization, for example, can take less than 15 min. The equipment is versatile and flexible in measurements and calculations. The size and shape parameters to be measured are determined by the researcher and not the instrument. The ease with which this information can be obtained from small samples early in the development process makes it a valuable tool for the formulator.


Sterile filtration of a parenteral emulsion.

The Syntex adjuvant formulation (SAF) containing [thr1]-muramyldipeptide in an oil-in-water emulsion has proven to be an effective adjuvant eliciting both cell-mediated and humoral immune response. As a parenteral emulsion, sterility of the final product was a concern, and various methods of achieving sterility were considered. For emulsions, most conventional sterilization methods are not viable, requiring the more cumbersome technique of sterilizing individual components and assembling/manufacturing under sterile conditions. Emulsion vehicles were manufactured with various models in the Microfluidizer M110 series. All equipment examined was capable of reducing the average dispersed oil droplet size to approximately 160 nm, with varying size ranges. Operating at an internal equipment pressure of greater than 16,000 psi, with at least five cycles through the interaction chamber, the resulting emulsion had a narrow droplet size range distribution, with the largest droplets being small enough to enable sterile filtration. Under specific-manufacturing conditions, the adjuvant emulsion becomes easily filtered through a 0.22-micron cartridge filter, thus yielding a sterile end product. This is the first published example of emulsion sterilization being achieved by terminal filtration.


Dissociation of insulin oligomers by bile salt micelles and its effect on alpha-chymotrypsin-mediated proteolytic degradation.

Bile salts have been found to be effective absorption promoters of insulin across mucosal barriers, i.e., nasal and gastrointestinal. One of the mechanisms proposed for absorption enhancement is the dissociation of insulin oligomers to monomers, rendering a higher insulin diffusivity. alpha-Chymotryptic degradation and circular dichroism studies were used to characterize such a transition. When zinc insulin (hexamers) and sodium insulin (dimers) were subjected to alpha-chymotryptic degradation, a 3.2-fold difference in the apparent first-order rate constants was observed (zinc insulin being slower than sodium insulin), representing the intrinsic difference in the concentration of total associated species in solution (three times). In the presence of a bile salt, sodium glycocholate (NaGC), the rate of degradation of both zinc and sodium insulin increased in an asymptotic manner. A maximum increase of 5.4-fold was observed for zinc insulin at a 30 mM NaGC concentration and a 2.1-fold increase was noted for sodium insulin at 10 mM NaGC, both values being close to the theoretical numbers of 6- and 2-fold as predicted by the complete dissociation of hexamers and dimers to monomers. The result indicates dissociation of insulin oligomers to monomers by bile salt micelles, probably by hydrophobic micellar incorporation of monomeric units. Circular dichroism studies also revealed progressive attenuation of molecular ellipticities at negative maxima of 276, 222, and 212 nm for zinc insulin solution in the presence of NaGC. Therefore, both alpha-chymotryptic degradation and circular dichroism studies have consistently demonstrated that the bile salts may be capable of dissociating insulin oligomers to monomers, a fact which may play an important role in enhancing insulin bioavailability.


Effect of zinc binding on the structure and stability of fibrolase, a fibrinolytic protein from snake venom.

Fibrolase is a metalloprotease with potential use as a fibrinolytic agent. Loss of the intrinsic zinc atom leads to a rapid decrease in enzymatic activity. Circular dichroism measurements indicate that there is a partial unfolding of an alpha-helical section of the protein concomitant with the loss of zinc. Removal of zinc can be affected by elevated temperatures, acidic pH values, and addition of chelating agents. At low molar concentrations, both ethylenediaminetetraacetic acid (EDTA) and dithiothreitol (DTT) were found to remove zinc efficiently. Analysis of the sequence of fibrolase identified a segment which possessed a high degree of homology with the metal binding site of other zinc proteases, such as thermolysin and the collagenases. However, the putative zinc binding site in fibrolase lacks the additional glutamate ligand found in thermolysin and subtilisin. This sequence is also predicted to adopt an alpha-helical conformation. Together, these data indicate that there is a well-defined metal binding site in fibrolase and that metal binding is the most important factor governing the stability of this protein.


Vaginal absorption of insulin in the rat: effect of penetration enhancers on insulin uptake and mucosal histology.

The absorption of insulin across the vaginal mucosa into the systemic circulation was studied in ovariectomized rats given subsequent estrogen treatment. Blood glucose levels were determined as an indirect measure of insulin absorption, and the effect of various enhancers on the hypoglycemic response was investigated. In the absence of any enhancer, no decrease in blood glucose levels was observed after vaginal administration of insulin. However, the coadministration of sodium taurodihydrofusidate, polyoxyethylene-9-lauryl ether, lysophosphatidylcholine, palmitoylcarnitine chloride, and lysophosphatidylglycerol significantly increased hypoglycemia, whereas citric acid had little effect. The histological changes in the vaginal epithelium after treatment with the enhancer systems were variable and often severe. While the efficacy of these compounds in promoting the vaginal absorption of insulin is encouraging, their mechanisms of action and long-term histological effects are yet to be defined.


The influence of different strains and age on in vitro rat skin permeability to water and mannitol.

Water and mannitol were used as test penetrants to study the effect of age on the skin permeability of the Wistar-derived Alderley Park (AP) rat and Sprague-Dawley (SD) rat. Whole-skin membranes were prepared from rats aged 10 to 120 days, while epidermal membranes were prepared from rats aged 24 to 32 days. The results indicated that the skin permeabilities of the two strains were very similar for either whole-skin or epidermal membranes. The influence of age on skin permeability was found to be negligible for the AP rat, and a small decrease in whole-skin permeability was observed for SD rats above 80 days of age. A statistically derived expression ("the separation efficiency factor") was used to determine the optimum age for preparing intact epidermal membranes; these were 26 days for AP rats and 28 days for SD rats. Histological examination of whole-skin membranes for both strains revealed that the stratum corneum and epidermal thickness did not alter significantly with age (10 to 120 days old). Dermal thickness, hair follicle depth, and, to a lesser extent, the surface area occupied by hair follicles all appeared to be influenced by age, although these changes had no detectable effect on skin permeability.


Oral delivery of a renin inhibitor compound using emulsion formulations.

The oral delivery of O-(N-morpholino-carbonyl-3-L-phenylaspartyl-L- leucinamide of (2S,3R,4S)-2-amino-1-cyclohexyl-3,4-dihydroxy-6-methylhetane (I), a new renin inhibitor, was studied in the in vivo rat model using emulsion formulations. The components of the emulsion formulations were chosen based on their proposed effects on membrane structure, membrane fluidity, and solute transport. The percent absolute bioavailability (%AB) of I was increased from 0.3% (water suspension) to 5.1% when long-chain unsaturated fatty acid (oleic acid, linoleic acid, etc.)- and mono- and diglyceride (monolein, dilaurin, etc.)-containing emulsion formulations were used. Considering very high first-pass liver extraction of the compound (80%), it is suggested that emulsion formulations increased the intestinal transport of the compound significantly. The solubility of I in aqueous media with and without bile salt (20 mM) was found to be low (approximately 1 micrograms/ml). Incubation in 0.01 N HCl did not affect the particle size of the emulsion. The titration of oleic acid/monoolein emulsion in a pH 6.5 medium with a mixed bile salt system indicated reduction in the particle size of the emulsion. Drug precipitation was observed above 30 mM bile salt concentrations. No drug crystals could be detected in the intestinal contents of the rats when emulsion formulations were ingested. These results suggest that in the intestine of the animals, the particle size of the emulsions is reduced in the presence of bile fluid while the drug resides primarily in the oil phase. The mechanism of enhanced transport of I from the emulsion formulations is discussed along with the possibility of cotransport for the drug and oil. Emulsion formulations can be a potential delivery form for low-bioavailable lipid-soluble drugs.


Intestinal water and solute absorption studies: comparison of in situ perfusion with chronic isolated loops in rats.

The effects of lumenal glucose on jejunal water transport and the influence of glucose-induced water absorption on solute uptake from single-pass perfusions are compared in anesthetized rats in situ and isolated chronic loops in unanesthetized rats in vivo. While the magnitudes of solute membrane permeabilities are consistently higher in the chronic loop system, the effects on water transport and its promotion of jejunal solute uptake are comparable between the two experimental systems. The effect of glucose-induced water absorption on the enhanced/baseline jejunal uptake ratio of the hydrophilic drug, acetaminophen, is greater than that for the lipophilic drug, phenytoin, in both experimental systems. The fact that chronic loop effective solute permeabilities were equivalent to solute membrane permeabilities in situ is consistent with greater lumenal fluid mixing in vivo. In addition, in situ body temperature affects the uptake of phenytoin but not acetaminophen, water, or glucose. This suggests that active and paracellular solute transport is not compromised in situ, while membrane partitioning and diffusion of lipophilic species are more sensitive to experimental conditions.


Absorption of flurbiprofen in the fed and fasted states.

The oral absorption of flurbiprofen, an antiinflammatory nonsteroidal compound, was compared in the fasted vs the fed state. When ingested as an aqueous solution of the sodium salt, absorption kinetics followed a monoexponential pattern in half of the subjects and a bimodal pattern with a lag time before the onset of the second phase of absorption in the other half of the subjects. When ingested in the free acid form as a tablet either with water (fasted state) or with water 15 min after 330 ml of apple juice (fed state), flurbiprofen absorption was always bimodal, and the lag time before the onset of the second phase was shown to be dependent on the gastric emptying time (r = 0.623, P less than 0.01). The gastric emptying times were significantly longer when the drug was administered in the fed state (average GET = 57 min in the fasted state and 102 min in the fed state; P less than 0.01). These results suggest that gastric emptying effects are one important way in which absorption of drugs can be affected by meal intake.


Effect of chronic administration of phenobarbital on the hepatobiliary transport of phenol red: assessment by statistical moment analysis.

The effect of enzyme induction on the hepatobiliary transport of phenol red (PR) in rats was investigated by application of a new analytical system to determine local drug disposition based on statistical moment theory (T. Kakutani et al., J. Pharmacokin. Biopharm. 13:609-631, 1985). Employing the moment parameters obtained from the time courses of plasma and biliary concentrations of PR and its metabolite after intravenous injection, the hepatobiliary transport of PR was theoretically assessed by separating it into component subprocesses such as hepatic uptake, hepatobiliary transfer, and intrahepatic metabolism. The results demonstrated that the acceleration of plasma disappearance of PR caused by pretreatment with phenobarbital (PB), known to induce hepatic enzyme systems, could be attributed to elevation of both hepatic and extrahepatic clearances. While PB did cause bile flow elevation (choleresis) and increased metabolism, these effects were shown to make little contribution to accelerated plasma disappearance of PR, since it was shown that the hepatobiliary excretion of PR was rate-limited by the intrahepatic transfer process, which was unaffected by PB treatment. From the results of this study, this experimental/analysis methodology seems to be useful in obtaining detailed information about hepatobiliary transport of the drug from in vivo data.


An in vitro pharmacodynamic model to simulate antibiotic behavior of acute otitis media with effusion.

The purpose of this investigation was to develop an in vitro pharmacodynamic model (IVPM) that would simultaneously simulate in vivo serum and middle ear amoxicillin pharmacokinetic characteristics of acute (purulent) otitis media and then utilize the IVPM to assess amoxicillin-mediated killing of a type 7F Streptococcus pneumoniae (MIC = 0.002 mg/L). The IVPM consisted of a sterile central compartment and a membrane-bound "infected" peripheral compartment. Peak peripheral compartment amoxicillin concentrations occurred within 2 hr after its introduction into the central compartment and were approximately 30% of peak central compartment concentrations. Amoxicillin elimination from the central compartment was designed to provide a 1-hr t 1/2. Amoxicillin elimination from the peripheral compartment was slower than from the central compartment, with an average half-life of 2.3 hr. Significant concentration-related differences in maximal bacterial kill rates were not detected over the range of amoxicillin concentrations studied (0.26 to 14.6 mg/L). However, at peak central compartment amoxicillin concentrations of less than or equal to 2 mg/L, a lag phase in killing was observed. In general, the in vitro pharmacokinetic data derived from this model compare well with published in vivo data.


Bioequivalence.

The bioequivalence of two formulations of the same drug may be determined by evaluating the similarity of their respective plasma concentration curves. The similarity of two plasma concentration functions can be measured by an index called the bioequivalence index. This paper shows how such an index may be defined and calculated.


Method for the determination of diphenhydramine in rabbit whole blood by high-performance liquid chromatography (HPLC) with ultraviolet (UV) detection in conjunction with gas chromatography (GC) with mass selective detection (MSD).

An HPLC/GC-MSD method for the determination of diphenhydramine in rabbit whole blood has been developed and validated. This method is based on a liquid-liquid extraction and reversed-phase chromatography with ultraviolet absorbance detection monitored at 258 nm. HPLC eluant fractions containing diphenhydramine and the internal standard, orphenadrine, were collected, reextracted, then subjected to GC-MSD analysis. Whole blood was utilized, thereby decreasing the required sample volume and increasing the sensitivity of the assay. Diphenhydramine concentrations can be quantitated over a range of 1 to 1000 ng/ml whole blood.


Investigation of the degradation mechanism of 5-aminosalicylic acid in aqueous solution.

The solution degradation of the antiinflammatory agent 5-aminosalicylic acid (5-ASA) was investigated in order to elucidate a mechanism for degradation. Two degradation pathways were considered: decarboxylation by analogy to 4-aminosalicylic acid (4-ASA) decomposition and oxidation from consideration of 5-ASA's aromatic ring substitution pattern (i.e., relation to p-aminophenol). The oxidation of 5-ASA was investigated using cyclic voltammetry and flow electrolysis. These studies showed that 5-ASA is more easily oxidized than is 4-ASA and that 5-ASA undergoes a two-electron, two-proton oxidation consistent with formation of 5-ASA-quinoneimine (5-ASA-QI). This oxidation is followed by subsequent complex chemistry. The decomposition of 5-ASA in solution was examined under a variety of conditions. 5-ASA decomposes most rapidly under conditions promoting oxidation and is most stable under conditions tending to inhibit oxidation. Decarboxylation was not found to be a significant degradation pathway.


Solid-state stability testing of drugs by isothermal calorimetry.

A new technique has been developed to calculate rapidly the solid-state room-temperature degradation rate of drugs and drug candidates. The technique utilizes measurements of the initial rate of heat output at several elevated temperatures by isothermal calorimetry and the degradation rate of the compound determined at a single elevated temperature by chromatography. The activation energies and degradation rates at 25 degrees C calculated by conventional methods and by isothermal calorimetry are compared and discussed. The compounds studied were phenytoin, triamterene, digoxin, tetracycline, theophylline, diltiazem, and several proprietary ICI compounds.


Effect of phosphamidon and obidoxime on the QT-RR relationship of isolated rat heart.

We studied the effects of phosphamidon (an organophosphate compound), obidoxime (a cholinesterase reactivator), and their combination, phosphamidon/obidoxime (PD/OB) on cardiac cycle length (RR), QT interval, and on QT-RR relationship of isolated rat heart. Cardiac cycle length did not change significantly following perfusion with phosphamidon or obidoxime alone; however, following perfusion with PD/OB, RR significantly increased at high concentrations (10(-3) M) of both drugs. The QT interval lengthened by 5% following perfusion with phosphamidon, did not change following perfusion with obidoxime, and increased by 10% following perfusion with PD/OB. The QT-RR relationship without drugs was positive and linear. Following perfusion with phosphamidon alone, the slope of the relationship decreased significantly, while perfusion with obidoxime alone did not change the QT-RR relationship. Perfusion with PD/OB at low concentrations decreased the slope of the relationship; however, at the highest concentration (10(-3) M) the QT-RR relationship was inverted and became negative. Ventricular arrhythmias as premature ventricular beats, or bigeminies, were noted with increasing frequency following perfusion with increasing doses of phosphamidon. Perfusion with obidoxime did not cause arrhythmias, whereas perfusion with PD/OB caused premature ventricular beats, bigeminies, and ventricular tachycardias at high doses. We suggest that obidoxime modulates the direct effects of phosphamidon on the cardiac repolarization process. PD/OB at high concentrations invert the normal depolarization-repolarization coupling and may therefore potentiate arrhythmias.


Inhibition of cumene hydroperoxide-induced lipid peroxidation by a novel pyridoindole antioxidant in rat liver microsomes.

The ability of stobadine, a novel pyridoindole antioxidant, to inhibit lipid peroxidation induced by cumene hydroperoxide was investigated in rat liver microsomes. In the micromolar range stobadine effectively inhibited lipid peroxidation as measured by the formation of thiobarbituric acid reactive products. The peroxidation-related degradation of microsomal cytochrome P-450 was prevented by stobadine in the same pattern. Another line of evidence in support of the antioxidant action of stobadine was given by its inhibition of cumene hydroperoxide-induced oxygen consumption in microsomal incubations. Inhibition of lipid peroxidation was not a function of decreased bioactivation of cumene hydroperoxide, as stobadine did not affect the rate of cytochrome P-450 dependent cleavage of cumene hydroperoxide. Neither had stobadine any effect on cytochrome P-450 peroxidase function characterized by the rate of cumene hydroperoxide-dependent oxidation of TMPD, and no direct spectral interaction with microsomal cytochrome P-450 was observed in the micromolar region. We suggest that it is the ability of stobadine to scavenge alkoxyl and peroxyl radicals that is predominantly responsible for the observed antioxidant effect.


Gentamicin nephrotoxicity in rat: some biochemical correlates.

The present work examines the effect of treatment of rats with graded doses of the aminoglycoside antibiotic gentamicin on the concentration of reduced glutathione (GSH) and diamine oxidase (DAO) activity in the kidney, and DAO activity, creatinine and magnesium (Mg) in the plasma. The animals were given the antibiotic intramuscularly in doses of 20, 40, and 80 mg/kg/day for 6 days, and were killed 24 hr after the last injection. In another experiment rats were injected intramuscularly with gentamicin at a dose of 80 mg/kg/day for 6 days and were killed 1, 7 or 14 days after the last injection, and the above parameters were measured. Gentamicin reduced the body weights of rats in a dose-dependent manner. The weight reductions were most marked on days 4, 5 and 6 of the treatment. The body weights gradually recovered on withdrawing of the drug, and by day 14, they were not significantly different from those of the controls. Gentamicin produced significant and dose-dependent decreases in the renal concentration of GSH. Seven and 14 days after withdrawing the drug, the GSH concentrations were still significantly below that of the controls. Plasma Mg concentrations were significantly decreased, and plasma creatinine concentrations significantly increased by gentamicin. These effects persisted 7 and 14 days after cessation of treatment. Plasma DAO activity was not detectable in the control or gentamicin-treated rats. In the renal cortex, the activity of the enzyme, measured 1, 7 and 14 days after the treatment, was not significantly different from that of the control. Histopathologically, the drug produced dose-dependent proximal renal tubular necrosis.(ABSTRACT TRUNCATED AT 250 WORDS)


Pharmacokinetics in rat of 3-chloro-4-(dichloromethyl)-5-hydroxy-2(5H)-furanone (MX), a drinking water mutagen, after a single dose.

The pharmacokinetics of 3-chloro-4-(dichloromethyl)-5-hydroxy-2(5H)-furanone (MX) was evaluated after a single oral or intravenous administration in the rats using 14C-labelled compound. Twenty to 35% of the dose was absorbed into circulation from the gastrointestinal tract as assessed from the excretion in urine. The mean elimination half-life of the radioactivity in blood (T1/2 k10) was 3.8 hr. Traces of radioactivity remained in the blood for several days. The tissues lining the gastrointestinal and urinary tract, kidneys, stomach, small intestines and urinary bladder contained the highest radioactivity. The activity declined slowest in the kidneys. Urine was the main excretion route. Seventy-seven % of the total amount excreted appeared in urine in 12 hr and 90% in 24 hr. No radioactivity was exhaled in air suggesting that elimination through respiration did not occur. After an intravenous administration of 14C-MX, the T1/2 k10, was much longer, 22.9 hr, and the total elimination half-life (T1/2 beta), 42.1 hr. The results indicate that MX is absorbed from the gastrointestinal tract to a considerable degree and it is excreted in urine very rapidly. A fraction of MX or its metabolites is retained in blood for a longer period of time. The pharmacokinetics of MX does not suggest extensive cumulation of MX in tissues after continuous exposure.


Local antinociceptive and hyperalgesic effects in the formalin test after peripheral administration of adenosine analogues in mice.

Adenosine administered to humans has been reported to induce pain after intravenous administration. On the other hand adenosine analogues have been shown to possess antinociceptive effects after peripheral and intrathecal administration in animals. The aim of the present study was to investigate the effect of peripheral administration of adenosine agonists with different affinities for the A1 and A2 adenosine receptors on a persistent pain stimulus using the formalin test. The drugs chosen were, R-phenylisopropyl-adenosine (R-PIA) with high affinity for the A1 receptor, N-ethylcarboxamide-adenosine (NECA) with almost equal affinity for the A1 and A2 receptor and 2-(2-aminoethylamino)-carbonylethylphenylethylamino-adenosin e (APEC) with high affinity for the A2 receptor. The drugs were mixed with formalin and administered subcutaneously into the dorsal hind paw in mice to study the local effects. They were also injected separately from the formalin solution in different paws to evaluate the systemic effect. The total time of licking the injected paw during the first 5 min. was recorded. In high doses all compounds reduced the licking activity, but a low dose of APEC (1 microM) injected together with the formalin solution had an algesic effect. All effects were antagonized by theophylline. These results suggests that A1 adenosine receptors mediate a local peripheral antinociceptive effect and the involvement of local peripheral A2 receptors in the enhancement of the algesic response.


Class III antiarrhythmic action and inotropy: effects of almokalant in acute ischaemic heart failure in dogs.

We studied the haemodynamic and metabolic effects of the novel class III antiarrhythmic agent almokalant (H 234/09) in acute ischaemic heart failure at a dose prolonging ventricular repolarization. In pentobarbital anaesthetized dogs, heart failure was induced by microembolization of the area supplied by the main left coronary artery until a stable left ventricular end-diastolic pressure (LVEDP) of 32 +/- 2 mmHg was achieved. Embolization depressed LV dP/dt(max), LV dP/dt(min), left ventricular systolic pressure (LVSP) and cardiac output. After intravenous infusion of almokalant (0.35 micrograms/kg) LV dP/dt(max) and LV dP/dt(min) were not significantly changed at paced cycle length of 300 msec., whereas LVSP and aortic pressure decreased both at spontaneous and paced cycle length of 300 msec. LVEDP remained unchanged. Heart rate decreased from 185 +/- 7 to 167 +/- 5 beats/min., and corrected QT-time (QTc) increased from 9.5 +/- 0.3 to 10.4 +/- 0.5 msec. Arterial concentration and net myocardial uptake of glucose, lactate and free fatty acids were not significantly influenced by almokalant. In conclusion, almokalant at a dose prolonging ventricular repolarization had no negative inotropic effect in acute ischaemic heart failure.


Antithrombotic activity of a new pyrazine derivative determined by the mouse antithrombotic assay.

A model of pulmonary microembolization in the mouse induced by infusion of epinephrine and collagen was used to determine antithrombotic activity of indomethacin and acetylsalicylic acid and of two newly synthesized pyrazine derivatives. One of the new agents provided marked protection of mice from thrombotic challenge with epinephrine and collagen. Its effectiveness was higher than acetylsalicylic acid (especially at small doses) but smaller than that of indomethacin. The same compound was similar to acetylsalicyclic acid with respect to the inhibition of in vitro human blood platelet aggregation. The new class of pyrazine derivatives (the so-called pyrazine CH- and NH-acids) appears interesting from the view-point of the studies of platelet aggregation and may yield potential antithrombotic drugs.


Evidence for cytochrome P450 2E1-mediated toxicity of N-nitrosodimethylamine in cultured perivenous hepatocytes from ethanol treated rats.

The involvement of cytochrome P450 in the liver toxicity of the potent carcinogen, N-nitrosodimethylamine (NDMA) was investigated in hepatocytes isolated from the periportal or perivenous region by digitonin-collagenase perfusion. Exposure of hepatocytes in culture to NDMA (0.5 or 5 mM) for up to 18 hrs caused little damage, but after 42 hr loss of cell viability became evident, and the extent of cell death was higher in perivenous cells than in periportal cells. Pretreatment of rats with ethanol caused a dramatically enhanced cell damage in perivenous cells (80%) compared to periportal cells (45%). This ethanol pretreatment caused a several-fold induction of cytochrome P450 2E1, as determined both with Western blot and as NDMA demethylase activity, and the effect was observed almost exclusively in perivenous cells. Isoniazid, an inhibitor of cytochrome P450 2E1, completely protected against NDMA toxicity. Glutathione dependent cytoprotective mechanisms and lipid peroxidation did not appear to be critical in NDMA toxicity, as evidence by lack of potentiation of toxicity by buthionine sulfoximine, an inhibitor of glutathione synthesis, and by the absence of increased lipid peroxidation. Instead, the higher expression of cytochrome P450 2E1 in the perivenous cells seems to be the main determinant for the regiospecific toxicity of NDMA, and, consequently, probably also for the associated genotoxicity.


Drug metabolism in rats with cancer induced by N-nitrosodiethylamine and phenobarbital.

The metabolism of R- and S-warfarin in vivo and in vitro, bufuralol in vitro, and antipyrine and debrisoquine in vivo were studied in rats with cancer induced by N-nitrosodiethylamine and phenobarbital treatment. Microsomal cytochrome P-450 content was greatly reduced in both healthy and cancerous parts of the livers of tumour-bearing animals. The specific activities of R-warfarin and bufuralol 1'-hydroxylases were significantly elevated in rats with cancer. The activities of S-warfarin hydroxylases expressed per mg microsomal protein were reduced in animals with cancer, whereas those of R-warfarin and bufuralol 1'-hydroxylases were not. The urinary excretion of R-7-hydroxywarfarin was increased and those of S-6- and S-4'-hydroxywarfarin decreased in rats with cancer. The correlations between microsomal formation and urinary excretion of all warfarin metabolites were poor, except for R-7-hydroxywarfarin. Antipyrine oxidation was increased in the cancerous state but the urinary metabolic profiles were similar in rats with cancer and in controls. The metabolism of debrisoquine was decreased in tumour-bearing animals. Antipyrine metabolism did not show any correlation with either warfarin or debrisoquine metabolism, whereas several relationships were observed between warfarin and debrisoquine metabolism and between warfarin and bufuralol metabolism.


Pharmacokinetics of imipenem/cilastatin sodium in children with peritonitis.

Fifteen children (3-12 years) with peritonitis were given imipenem/cilastatin intravenously (15 or 25 mg/kg) every six hours for 3-14 days. One day during treatment days 2-8, multiple blood and urine samples were collected from each individual over a six hour dosing interval. Twelve children completed the study. The urinary recovery of imipenem and cilastatin averaged 50-70% of the administered dose. The plasma t1/2 for imipenem averaged 55 min. while that for cilastatin was even more rapid (approximately 38 min.). Little or no accumulation of either imipenem or cilastatin was observed for this regimen in this age group of paediatric patients. Steady state conditions prevailed within 2 days of initiation of therapy. The pharmacokinetics of imipenem and cilastatin in paediatric patients 3-12 years of age appear similar to those observed for adults.


GEA 857, a putative blocker of potassium conductance, enhances muscarinic agonist-evoked responses: dissociation from an action on 5-HT mechanisms.

GEA 857 [2-(4-chlorophenyl)-1,1-dimethylethyl 2-amino-3-methylbutanoate], a structural analogue of the 5-HT uptake blocker alaproclate, was tested for its ability to modify tremor and salivation induced by muscarinic agonists (oxotremorine, arecoline) and acetylcholinesterase inhibitors (physostigmine, THA) in the male rat. These agents were employed at submaximal doses. GEA 857, similarly to alaproclate (Ogren et al. 1985a & b), produced a dose-dependent, statistically significant (in the 5-20 mg/kg dose range) enhancement of the tremor response induced by all four cholinergic stimulants. However, unlike alaproclate, GEA 857 failed to enhance salivation in a consistent manner. GEA 857 itself did not produce tremor in the absence of the muscarinic agonists or the acetylcholinesterase inhibitors. The potentiation of oxotremorine tremor by GEA 857 could be fully blocked by atropine (1 mg/kg intraperitoneally). Unlike alaproclate, GEA 857 failed to affect 5-HT uptake or 5-HT metabolism in the 10-20 mg/kg dose range. However, similarly to the action of alaproclate, the potentiating effect of GEA 857 on muscarinic responses could be explained neither by actions on serotonergic mechanisms nor by actions on muscarinic receptor mechanisms in the striatum. Evidence is presented suggesting that the ability of GEA 857 to enhance responses evoked by muscarinic agonists involves inhibitory properties of GEA 857 at certain membranal Ca(2+)-dependent K+ channels, the blockade of which can potentiate or prolong muscarinic cholinergic actions.


Obidoxime augments the positive inotropic effect of phosphamidon on the isolated working rat heart.

The present study was designed to determine modulation of the direct inotropic effect of an anticholinesterase organophosphorus compound, phosphamidon, by the reactivator obidoxime. We investigated the effects of phosphamidon (n = 9), obidoxime (n = 5), and their combination (n = 5) on the mechanical and energetic indices of left ventricular function, in the isolated working rat heart model. Phosphamidon at a concentration range of 10(-6)-10(-3) M had a positive inotropic effect. Obidoxime at a concentration range of 10(-6)-10(-3) M had no significant effect on heart rate, but did have a statistically significant positive inotropic effect on end-systolic pressure, cardiac output, mean left ventricular pressure, and maximal time derivative of left ventricular pressure (dP/dtmax) (P less than 0.01). Perfusion with 10(-3) M obidoxime caused a 19% increase in left ventricular stroke work and a 31% increase in total pressure-volume area. Perfusion with phosphamidon and obidoxime at concentrations ranging from 10(-6) to 10(-3) M resulted in a more intense inotropic response than the separate drug effects. At the highest combined concentrations tested, cardiac output increased by 60%, left ventricular stroke work increased by 100%, and left ventricular total pressure volume area increased by 111% of their control values (P less than 0.001). We conclude that obidoxime augments the positive inotropic effect of phosphamidon on the isolated working rat heart.


Elimination of PCB congeners via milk in rabbits administered Fenclor 64.

A single dose of 100 mg per kg body weight of a commercial mixture of polychlorinated biphenyls (PCB), Fenclor 64 was given intraperitoneally to pregnant rabbits. The distribution in dams and foetuses and excretion in milk was investigated for six of the congeners by quantifying them in fat from maternal adipose tissue, from whole foetuses and newborn bodies and from newborn gastric contents. The cytochrome-P-450 induction after Fenclor 64 in foetuses and suckling off-spring was followed by measuring the following hepatic mixed function oxidase (MFO) activities: p-nitroanisole-demethylase, ethoxyresorufin-deethylase, ethoxycoumarin-deethylase and NADPH cytochrome-C reductase. At the 28th day of pregnancy PCB fat concentrations in foetuses were similar to those in mothers (126.4 +/- 7.1 and 152.6 +/- 28.1 micrograms/g of fat, respectively). By the 5th day of life fat concentrations in the youngs were double those of foetuses (216.81 +/- 8.12 micrograms/g) and remained high until weaning (142.2 +/- 15.5 micrograms/g at the 20th day). PCB concentrations in mothers' fat decreased during lactation (104.1 micrograms/g at the 20th day) but at the end of the experiment they were still high (95.5 micrograms/g). The cytochrome-P-450 concentration and MFO activities in young rabbits' livers from treated dams were significantly higher than controls from the 5th (P less than 0.01) to the 10th (P less than 0.01) day of life, with the exception of NADPH-cyt-C-reductase (P less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)


Inhalation kinetics of C6 to C10 aliphatic, aromatic and naphthenic hydrocarbons in rat after repeated exposures.

The toxicokinetic properties of C6 to C10 n-alkanes, aromates and naphthenes have been investigated in rats during inhalation of 100 p.p.m. of the single hydrocarbons for 3 days, 12 hr/day. The concentration of hydrocarbon was measured by head space gas chromatography in blood, brain, liver, kidneys and perirenal fat at days 1, 2 and 3, immediately after termination of exposure and 12 hr after exposure on day 3. The main conclusions drawn from the study were: a) Aromatic hydrocarbons show high concentrations in blood and low concentrations in organs. b) Naphthenic hydrocarbons show low concentrations in blood and high concentrations in organs. c) n-Alkanes show very low concentrations in blood, relatively high concentrations in brain and a high potential for accumulation in fat with repeated exposures. d) Biological concentrations of hydrocarbons within one class increase in general with increasing molecular weight, though with specific exceptions. e) Accumulation is obviously influenced by differences in metabolism and enzyme induction potential. f) Lipid solubility is not the only parameter relevant for the evaluation of hydrocarbon accumulation.


Single dose pharmacokinetics of trazodone in healthy subjects.

Eight healthy subjects were administered trazodone-HCl orally (100 mg) with and without food and by infusion in a three way cross-over study. Unchanged trazodone was determined in serum and urine by high performance liquid chromatography after an alkaline extraction. Absorption of trazodone was irregular in fasting subjects and improved after food intake. Food intake significantly decreased the maximum serum concentrations of trazodone from 1.88 +/- 0.42 to 1.47 +/- 0.16 micrograms/ml, and increased the time for reaching maximum concentration from 1.3 +/- 0.8 hr to 2.0 +/- 1.5 hr. No differences were observed in the total amount of trazodone absorbed with or without food with bioavailability values of 65 +/- 6 and 63 +/- 4 per cent, respectively. The apparent volume of distribution and total body clearance for trazodone were estimated to 0.84 +/- 0.16 l/kg and 5.3 +/- 0.9 l/hr, respectively. The terminal elimination half-life of 7.3 +/- 0.8 hr showed no significant differences between the different ways of administration. Urinary excretion of unchanged trazodone during 26 hr was less than 0.13 per cent of the administered dose, suggesting a high degree of trazodone metabolism. Earlier statements of enterohepatic circulation of trazodone and pharmacokinetic differences between males and females were not confirmed by the present study. Due to the irregular absorption in fasting subjects, trazodone should preferably be administered after food.


In vitro and in vivo evaluation of the genotoxicity of N-nitrosooxprenolol.

N-nitrosooxprenolol (NO-oxprenolol) might be formed in the stomach of patients taking the beta-adrenergic blocking drug, oxprenolol. This nitroso derivative has previously been shown to induce DNA damage and repair in both rat and human cultured hepatocytes. The results of the present study show that in the presence of co-cultured rat hepatocytes, 0.03 mM NO-oxprenolol produced a significant increase in the frequency of 6-thioguanine-resistant but not of ouabain-resistant mutants. No mutagenic activity was detected in the absence of metabolic activation. In mice, NO-oxprenolol (1 g/kg) increased the incidence of micronucleated cells in the liver but not in the bone marrow and the spleen. These results suggest that NO-oxprenolol, consistent with its chemical nature of nitrosamine, is biotransformed into short-lived reactive species.


Reward and abuse of opiates.

The dependence creating properties of drugs are mediated by structures in the brain. The mesolimbic system seems to play a crucial role in the behaviourally reinforcing effects of opiates and other drugs of abuse. The significance of dopamine in opiate reinforcement is still a matter of debate, in spite of the large number of studies on this subject. Dopamine appears to be involved in conditioning processes and in drug self-administration behaviour only once it has been established. Neuropeptides, centrally active fragments of hormones, may play a role in the individual vulnerability for the development of drug dependence. Administration of a number of wellknown neuropeptides attenuates the acquisition of drug self-administration behaviour. The virtues and flaws of some widely used animal models for drug dependence are discussed.


Amiloride derivatives as blockers of Na+/Ca2+ exchange: effects on mechanical and electrical function of guinea-pig myocardium.

The amiloride derivatives, 2',3'-benzobenzamil (BB), 3',4'-dichlorobenzamil (DCB), and 5-(N-4-chlorobenzyl)-2',4'-dimethylbenzamil (CBDB) are known as inhibitors of the Na+/Ca2+ exchange. This kind of drug action was recently suggested to be a new inotropic mechanism. In guinea-pig myocardium, we have studied the inotropic and the accompanying electrophysiological effects of the three compounds in order to assess their selectivity of action. In left atria and in papillary muscle, force of contraction increased with DCB and CBDB (atria only) at a high concentration (5 x 10(-5)-10(-4) mol/l) and after long exposure time, whereas BB produced a negative inotropic effect. In the isolated perfused Langendorff heart, the amiloride derivatives tested decreased spontaneous heart rate and force of contraction and prolonged the duration of contraction. In isolated cardiac myocytes, sodium current, calcium current and the delayed rectifier were reduced by concentrations of BB, DCB and CBDB similar to the IC50 values reported for the inhibition of the Na+/Ca2+ exchange. Our results demonstrate that the amiloride derivatives have multiple sites of action. It is concluded that more specific modulators of the Na+/Ca2+ exchange are required in order to define their contribution to the regulation of contractile activation of the heart.


Effect of chloroquine on some carbohydrate metabolic pathways: contents of GHS, ascorbate and lipid peroxidation in the rat.

Adult male rats were treated intraperitoneally with chloroquine (5 mg/kg/day) for 9 days. A reduction in the fasting plasma glucose level by 17.6% and ascorbic acid by 45% were discernable. The treatment caused significant increase in liver lactate dehydrogenase and glucose-6-phosphate dehydrogenase activities and reduced the activity of succinate dehydrogenase enzyme. Chloroquine also caused significant reductions in the contents of reduced glutathione and ascorbic acid in the brain and erythrocytes with a significant increase in lipid peroxidation.


Mutagenicity of crude senna and senna glycosides in Salmonella typhimurium.

The mutagenicity of senna glycosides and extracts of senna folium and senna fructus was investigated in the Salmonella typhimurium reversion assay. Senna glycosides were inactive in all strains, except for a slight, but significant increase in mutant frequency in TA102 in the absence and presence of liver microsomes. Extracts of senna fructus and senna folium demonstrated weak activity in TA97a, TA100 and TA102 in the presence of liver microsomes, and in TA97a and TA102 in the absence of liver microsomes. A strong increase in mutant frequency (3- to 5-fold above background frequency) was observed with all extracts in TA98 in the presence of liver microsomes. This activity increased further following enzymatic hydrolysis with hesperidinase of extracts of senna fructus from one source, and could be correlated to the release of the flavonol aglycones kaempferol and quercetin. The weak or lacking activity of anthraquinone aglycones in the tested strains of Salmonella typhimurium indicates that mutagenicity can not be attributed solely to the anthraquinone content of these plant materials. The chemical nature of other mutagenic components has not been elucidated.


Enhancement of morphine-induced analgesia and attenuation of morphine-induced side-effects by cocaine in rats.

Effect of cocaine on morphine-induced analgesia and the accompanying respiratory depression, bradycardia and hypolocomotion/sedation was studied in rats. Cardiovascular and respiratory effects were studied under pentobarbitone-induced anaesthesia. Cocaine enhanced morphine-induced analgesia in the formalin test, hot plate test and heat-induced tail withdrawal test in intact rats. However, in spinal rats a similar combination of cocaine with morphine did not produce increased latencies in the tail withdrawal test. Of the three analgesic tests used, the formalin test was the most sensitive to the enhancement, as well as to the effects of morphine or cocaine alone. Morphine at the dose of 6 mg/kg produced complete analgesia in the formalin test, significant hypolocomotion/sedation, significant bradycardia and significant decrease in the respiratory rate. At an equianalgesic dose (complete analgesia in the formalin test) of morphine (3 mg/kg)-cocaine (5 mg/kg)-combination no significant changes in heart rate, respiratory rate or locomotion(/alertness) were observed. Changes in skin blood flow determined by the laser Doppler flow method were not significant in any of the experimental conditions. The results indicate that cocaine enhances morphine-induced analgesia, mainly due to supraspinal mechanisms. In contrast, the morphine-induced bradypnoea, bradycardia and hypolocomotion/sedation are attenuated by cocaine.


Changes in concentration of essential metals in kidneys and urine as indices of gentamicin nephrotoxicity in female Wistar rats.

Wistar rats were treated with gentamicin in single (80 mg/kg) or repeated doses (7 x 40 mg/kg) subcutaneously. Total protein as well as excretion of essential metals (Cu, Zn) with the urine were determined 24 hr after 1, 3 and 7 dosages as well as 3 and 7 days after the termination of administration. At the same time kidneys were examined histopathologically by light microscopy. Simultaneously, Cu, Zn and metallothionein levels in kidneys and liver were determined. Rats receiving gentamicin demonstrated progressive renal proximal tubular necrosis at the end of 7 days administration. At the same time elevated copper and zinc levels were observed in urine. These essential metals seem to be an indicator of gentamicin nephrotoxicity.


Tri-n-butyltin increases intracellular Ca2+ in mouse thymocytes: a flow-cytometric study using fluorescent dyes for membrane potential and intracellular Ca2+.

Effects of tri-n-butyltin (TBT) on mouse thymocytes were examined using a flow-cytometer and fluorescent dyes for membrane potential and intracellular Ca2+ ([Ca2+]i). TBT at concentrations from 1 x 10(-7) M to 3 x 10(-7) M caused hyperpolarization in thymocytes during 30 min. after drug application in a time- and dose-dependent manner. Further increase in TBT concentration (to 1 x 10(-6) M) made hyperpolarization of thymocytes more profound within 5 min. after application, thereafter gradually depolarized them during the next 25 min. TBT at 3 x 10(-8) M or more (up to 1 x 10(-6) M) increased the [Ca2+]i of thymocytes. After reaching maximum [Ca2+]i at the various TBT concentrations used within 5 min. after drug application, the [Ca2+]i slightly decreased in a time-dependent manner. Effects of TBT on membrane potential and the [Ca2+]i were greatly reduced under nominal external Ca(2+)-free condition. Results suggest that TBT can promote Ca(2+)-influx to thymocytes, resulting in hyperpolarization by activation of Ca(2+)-dependent K+ current. The increase in [Ca2+]i by TBT may be related to its cytotoxic action on thymocytes.


The effect of chloral hydrate and its metabolites, trichloroethanol and trichloroacetic acid, on bilirubin-albumin binding.

Chloral hydrate is used as a sedative in infants requiring ventilatory support. The metabolites, trichloroethanol and trichloroacetic acid, accumulate in the serum and are protein bound. The possibility that these chemicals might compete with bilirubin for albumin binding was tested using the peroxidase method and a dialysis rate method. Chloral hydrate and trichloroethanol had no effect on bilirubin-albumin binding. Trichloroacetic acid affects bilirubin-albumin binding but to a degree that would be dangerous only in infants with an unusual accumulation of this metabolite.


Breathing zone concentrations of methylmethacrylate monomer during joint replacement operations.

By use of a methylmethacrylate (MMA) Dräger tube and bellow bump, the breathing zone concentrations of MMA monomer were measured for the operating surgeon during cementation of the components of hip and knee joint prostheses. The highest recordings (50-100 p.p.m.) were encountered during cementation of the acetabular cups with conventional polymethylmethacrylate cement. Such exposure could be eliminated by the use of personal protection equipment, local punctual field suction or change to a MMA/n-decylmethacrylate/isobornylmethacrylate bone cement.


Sensory irritation effects of methyl ethyl ketone and its receptor activation mechanism.

The burning and painful effect in nose and eyes, termed sensory irritation, of methyl ethyl ketone vapours was investigated in a mouse bioassay. Sensory irritation is mediated via the trigeminal nerves and results in a reflexively induced decrease in respiratory rate in mice. Methyl ethyl ketone was used as a model substance for ketones. At the lower exposure concentrations a partial fading (desensitization) of the response was seen. Little desensitization was seen at higher concentrations. n-Propanol, a model substance for alcohols, desensitized the receptor at all exposure levels. Preexposure to propanol did not influence the response at high methylethyl ketone concentrations. This suggests that the two substances bind to different receptive sites with different properties, if the ketone response is due to a high exposure concentration. A decrease in tidal volume was also mediated from the upper respiratory tract. The tidal volume effect is mediated by nerves different from those mediating the frequency response, as the time-response relationship, the desensitization pattern, the maximum response and the apparent dissociation constants were different for the two types of effect. Neither the location nor the perceived response related to the volume response is known.


Enzyme activities in the term human placenta: in vitro effect of cadmium.

The effect of cadmium (Cd) as CdCl2 on some placental enzyme activities were studied after explants had been incubated with the salt for 6 or 24 hr. The results indicated that, for both incubation periods, Cd at low doses had a stimulatory effect on aryl hydrocarbon hydroxylase (AHH) (a phase I enzyme) and on quinone reductase and catecholamine-O-methyltransferase (COMT) (both phase II enzymes). This effect was dose- and time-dependent. Only the activities of AHH and COMT showed a biphasic response, (i.e., increases at the lower dose levels and decreases with the higher ones), whereas that of quinone reductase continually increased with all the dose levels of the metal administered. Glucose-6-phosphate dehydrogenase (G-6-PD) activity was found to be inhibited at all the dose levels of Cd tested, the effect also being time- and dose-dependent. In conclusion, it appears that the use of placental explants can serve as a valuable means for studying the toxic effects of certain xenobiotics, as reflected in the activity of various important enzymes.


Characterisation of dopamine and serotonin uptake inhibitory effects of tetrahydroaminoacridine in rat brain.

The effects of 1,2,3,4-tetrahydro-9-aminoacridine (THA) on uptake rates of radioactive 5-hydroxytryptamine (5-HT) and dopamine were investigated in rat diencephalon and striatal homogenates, respectively. Six and eight microM of THA were needed to inhibit 50% of dopamine and 5-HT uptake rates. Kinetic parameters, Km and Vmax, using six different concentrations of dopamine and 5-HT were estimated in the presence or absence of THA. A significant decrease in Vmax without any change in Km values was observed for both dopamine and 5-HT in the presence of THA. The results show that THA is a non-competitive uptake inhibitor of dopamine and 5-HT in the nerve terminals. The re-uptake blocking effect of THA on dopaminergic and serotonergic neurones, following THA treatment, might lead to increased levels of these monoamines in brains of Alzheimer patients and contribute in the therapeutic effects of the drug.


Relationship between histamine, lipoxygenase and cyclooxygenase products in antigen-induced contraction in guinea-pig tracheal tube preparations.

We have used a tracheal tube preparation to study antigen-induced contraction in sensitized guinea pig airways. Treatment with both the cyclooxygenase inhibitor indomethacin and the lipoxygenase inhibitor MK-886 (L-663,536) affected this contraction in preparations with intact epithelium. Indomethacin potentiated and MK-886 inhibited part of the contraction. Leukotriene release from tracheal tubes was measured after antigen challenge, and was found to be significant in preparations with an intact epithelium. When the epithelium was removed, the histamine receptor antagonist mepyramine reduced antigen-induced contraction by 90%. Our results show that when the epithelium is absent, histamine is the most important mediator in the contraction. With the epithelium left intact, the contraction is more complex: both the cyclooxygenase and lipoxygenase pathways are involved, and our findings indicate that eicosanoid production is associated with the airway epithelium.


Dose dependent induction of the microsomal monooxygenase aryl hydrocarbon hydroxylase in isolated peripheral blood monocytes: the influence of age.

The induction of the microsomal monooxygenase benzo(alpha)pyrene hydroxylase was investigated in isolated peripheral blood monocytes from young and old donors, after exposure to different concentrations of benzanthracene as an inducing agent. The sensitivity of the cells to the inducing stimulus was not dependent on the age of the donor. The mechanisms underlying impaired monooxygenase induction in the elderly remain to be clarified.


Naloxone counteracts the fast development of tolerance to morphine in guinea-pig ileum.

The ability of naloxone to inhibit the fast development of tolerance to morphine was examined in the guinea-pig ileum preparation. Dose-response curves were obtained either non-cumulatively with morphine alone or cumulatively with morphine alone and in combination with different concentrations of naloxone. We present some theoretical considerations concerning the competitive interaction between agonist and antagonist on a receptor. According to these theories, it is possible to perform dose-response experiments for an agonist in combination with different concentrations of antagonist and extrapolate to the dose-response curve for agonist alone and to the dissociation constant for the antagonist. EC50 values for morphine alone obtained either non-cumulatively or by extrapolation are almost identical and are significantly lower than those obtained cumulatively. The results indicate that tolerance develops very quickly when dose-response curves are obtained cumulatively with morphine alone and that low concentrations of naloxone counteract the development of tolerance.


Frequency- and potential-dependency of the negative inotropic action of various dihydropyridine and non-dihydropyridine calcium antagonists.

Transmembrane voltage and beat frequency are important determinants of the action of several organic calcium antagonists. This is well-known for the cationic amphiphilic calcium antagonists. We intended to assess the functional impact of these phenomena in cardiac muscle with special regard to dihydropyridines. Therefore, concentration-response curves were constructed in isolated guinea-pig left atria for the negative inotropic effect of various compounds. The dihydropyridines nifedipine, racemic nitrendipine, nisoldipine, and felodipine, and the enantiomers of isradipine were investigated at different stimulation frequencies (1 Hz, 2.5 Hz, 4.5 Hz), and at different extracellular K+ concentrations (2.7 mM, 5.4 mM, 10.8 mM). These drugs were compared with the cationic amphiphilic compounds gallopamil, verapamil and diltiazem. The potency of some dihydropyridines, particularly nitrendipine, could be modulated to a remarkable extent, covering several orders of magnitude. The potential-dependency of the drugs depended on stimulus frequency and ranged from less than a half to two orders of magnitude. At 2.5 Hz, the rank order of extent of potential-dependency was gallopamil greater than nitrendipine greater than diltiazem greater than verapamil = (+)-isradipine greater than (-)-isradipine greater than or equal to nisoldipine greater than or equal to felodipine = nifedipine. Based on data obtained from binding studies in intact atria and from patch-clamp measurements of calcium current blockade, a mathematical model was used which describes the observed potency changes.(ABSTRACT TRUNCATED AT 250 WORDS)


Metrifonate and tacrine: a comparative study on their effect on acetylcholine dynamics in mouse brain.

Tetrahydroaminoacridine (THA) and metrifonate are cholinesterase inhibitors used in the treatment of Alzheimer's disease. In experimental animals they inhibit acetylcholinesterase activity and have been reported to increase levels of brain acetylcholine. This paper presents results from studies of their effect at two dose levels on the dynamics of acetylcholine in mouse brain. Metrifonate at two doses (10 and 30 mg/kg intraperitoneally), known to cause cholinesterase inhibition, had no effect on levels of acetylcholine or choline or on the rate of synthesis of acetylcholine. THA (3 mg/kg intraperitoneally) had no effect on levels of acetylcholine and choline but had a shortlasting decreasing effect on the synthesis rate of acetylcholine. THA (10 mg/kg intraperitoneally) increased levels of acetylcholine and choline and markedly decreased the synthesis rate of acetylcholine. At this dose, the animals showed severe cholinergic effects, e.g. tremor and salivation. It is suggested that a moderate cholinesterase inhibition in brain facilitates cholinergic nerve transmission which is obtained at a broader dose range for metrifonate than for THA.


[The psychosocial questionnaire for pediatric oncology].

A concept based on empirical data is needed for psychological support of children with cancer and their families. A number of concepts are already available, but a psychological assessment is needed, which controls the feasibility of these concepts. The psychosocial questionnaire is such an assessment, which transforms individual data into the practical psychosocial work during the entire course of cancer treatment. The diagnostical procedure includes aspects of coping with cancer, such as stress, protective and risk factors and health behavior. Data are collected before, during and after the intensive cancer treatment and in a follow-up after 6 or 12 months respectively. The questionnaire has four parts. Each contains a "handbook for parents", which informs the parent in detail on each part. Thus, we enforce the potential of each parent to help him-/herself.


[Involuntary childlessness: a family problem].

Infertility--the inability to conceive or carry a pregnancy to live birth--will be experienced by 10% of the population of childbearing age. Infertility is known as a global problem through ages and has different cultural consequences. The infertile couples represent one neglected and silent minority group. Medical treatment have made great strides in discovering and curing infertility problems in recent years. These cures are not achieved without cost. A couple may incur tremendous physical, emotional and financial expose during the medical treatment phase. The author refers the most common psychic reactions to the emotional crisis that arise when couples experience infertility problems. She assumes that individuals or couples often will benefit from professional help and support when working through their emotional crisis.


[Family therapy in divorce].

A multi-generational approach to family therapy with divorce families is presented. Parents and children of such families are faced--with special problems during the phases of ambivalence, divorce and post-divorce. Their problems require varying focal points during therapeutic treatment. It focuses on arriving at a decision, finding constructive solutions for practical and emotional problems caused by the divorce ("psychic divorce" and parental cooperation concerning custody and education of the children) as well as supporting individuation and re-orientations. The main aim of therapeutic treatment is to alter the underlying pathogenic patterns of relationships and conflict-solving in order to prevent its repetition in a new partnership or in the next generation. Family therapy with divorce families is complicated to a high degree by aggressiveness, destructivity and resistance against working on central conflicts which serve to avoid feelings of anxiety, shame, guilt, anger and mourning.


[Coping with individuation problems of epileptic adolescents and young adults using a multidisciplinary counseling team].

Adolescence is a phase of development in which independence and a self-controlled life are being struggled for. Both the adolescents and their parents have the chance to reduce dependencies and become more and more autonomous. Epilepsy and its concomitants prevent patients from having the same lifestyle as healthy adolescents without such restrictions. Every seizure means a loss of control and is an impediment in the development towards autonomy and independence. Strategies for coping with these difficulties are dependent upon several factors: the time when the first seizures began, frequency of seizures, possible accompanying brain damage, effects of anti-epileptical drugs on behaviour, family structure and the personality of the adolescent. Highly complicated situations often arise when there is a combination of both uncleared medical questions as well as difficult psychosocial conditions. The development of more autonomy is obstructed by the fear of further seizures and this fear coincides with the process of separation from the parents at this stage of life. Epileptological and psychotherapeutic competence is needed for counseling families in these serious situations. Multidisciplinary cooperation is needed for analysing the problems of adolescents with epilepsy and their families. Only in this way can adequate strategies of intervention be developed. Two typical examples of such separation crises in adolescents with epilepsy and the supportive management of these crises through multi-disciplinary counseling shall be demonstrated.


[A brief psychotherapeutic synergistic approach in child and adolescent psychiatry].

The controversy between the concepts of family therapy and systemic therapy is one issue to design a synergetic concept of brief therapy in the psychiatric treatment of children and adolescents. Some principles of the radical-constructivism, systemic theory an the psychology of narratives will be discussed and related to concepts of solution-oriented brief therapy. A case example demonstrates the perspectives of this approach in the ambulant psychiatric treatment.


[Music therapy in a child and adolescent psychiatry department].

Psychotherapy with children and adolescents makes use of methods focusing on the non-verbal area, including music therapy. The following article presents music therapy focus and techniques as practiced in an children's and adolescents' psychiatric department. A case study provides illustration, and in the final section theses on the use of music therapy in this field are presented.


[Mythodrama--a group psychotherapy model for work with children and adolescents].

This article discusses group psychotherapy as a possible crisis intervention technique for children and juveniles with behavioral problems at school or whose families are going through divorce, or as an intervention technique in trouble some school classes. The therapeutic group work at the Children and Juvenile Educational Counselling Centre in Bern, Switzerland, is described - "mythodrama" or the "tales, fiction and horror technique", a therapeutic approach which was developed during the last couple of years. The tale at the beginning of the article serves as an introduction and is followed by a description of the different phases of mythodrama. Finally, the main elements of this approach are summarized.


Meconium peritonitis: extrusion of meconium and different sonographical appearances in relation to the stage of the disease.

By chance, we had the opportunity to make serial sonographic observations of the extrusion of meconium in a case of meconium peritonitis. Inflammation leads to exudative processes and production of fluid (ascites) in the fetal abdomen. Sonography at that stage of the disease may lead to a misdiagnosis such as 'fetal ascites' or 'non-immune hydrops'. After bowel perforation and extrusion of meconium, the latter appears as a solitary mass inside fetal ascites or as disseminated echogenic masses distributed subdiaphragmatically or perihepatically. Within a couple of days, in most cases the echogenicity of the masses increases. Calcifications lead to distinct shadowing. These calcifications are often the only visible signs of a previous meconium peritonitis. Serial sonograms are essential for the management of pregnancies with meconium peritonitis. If the amount of fetal ascites does not increase and no signs of cardiovascular stagnation appear, no invasive intrauterine diagnostic and therapeutic steps are required. In none out of the nine cases was a cause found.


Introduction of early amniocentesis to routine prenatal diagnosis.

With growing awareness of the problems associated with prenatal cytogenetic diagnoses after CVS, attempts have been made to provide early amniocentesis as an alternative to CVS. Since 1990, at our clinic the gestational age limit for routine diagnostic amniocentesis has been successively lowered, first to 14 and then to 13 weeks of gestation. Thus, 811 prenatal diagnoses were performed after early amniocentesis at 13 weeks (n = 217) and at 14 weeks of gestation (n = 594). No problems were encountered. Culture failure was never observed in the early samples. Using the criteria 'number of colonies' and 'culture duration until harvest', early samples taken at 14 weeks did not differ significantly from the controls after standard amniocentesis performed at 15 and 16 weeks, respectively, whereas a minority of samples taken at 13 weeks experienced some delay in culturing. However, in each group at least 85 per cent of samples led to a diagnosis fulfilling our standard criteria of a safe diagnosis (at least 20 metaphases of at least five colonies from at least one primary culture after trypsinization) within 15 days. Some differences between the different groups can be recognized: culture duration of less than 11 days tends to be increasing after standard amniocentesis, whereas long culture duration (more than 20 days) is more often associated with early amniocentesis. However, this trend is only minimal and did not result in an increased risk of missing a diagnosis.


Pseudomosaicism, true mosaicism, and maternal cell contamination in amniotic fluid processed with in situ culture and robotic harvesting.

This study was designed to test the usefulness of the common definitions for maternal cell contamination, true mosaicism, and pseudomosaicism for amniotic fluid specimens processed by in situ culture and robotic harvesting. We prospectively studied 4309 consecutive amniotic fluid specimens processed with these methods and found that 0.84 per cent had maternal cell contamination, 0.28 per cent had true mosaicism, and 5.4 per cent had pseudomosaicism. Although the frequencies of maternal cell contamination and true mosaicism were comparable to those in similar published studies, the frequency of pseudomosaicism was more than twice as high as that in previous reports. This finding is most likely not due to the method, but rather to a more accurate estimate of the actual frequency of pseudomosaicism in amniotic fluid cultures than reported heretofore. Follow-up clinical information was available on 72 per cent of the cases. In three cases of true mosaicism involving structural anomalies, the results of cytogenetic follow-up studies on the neonates were normal. None of the pseudomosaic cases involving trisomy 8, 13, 18, or 21; triple X; or monosomy X were associated with newborns who had birth defects.


The significance of choroid plexus cysts in fetuses at 18-20 weeks. An indication for amniocentesis?

Over a period of 25 months, all antenatal patients were offered a detailed ultrasound scan at 18-20 weeks' gestation. The lateral cerebral ventricles were scanned for the presence of choroid plexus cysts. Fifty-one patients found to have choroid plexus cysts were offered amniocentesis to exclude chromosomal abnormalities. One pregnancy, in which the only abnormality found was bilateral choroid plexus cysts, was terminated after trisomy 18 was detected on amniocentesis at 19 weeks. The other 50 pregnancies had normal fetal outcomes. The significance of the isolated finding of choroid plexus cysts is reviewed.


Early second-trimester sonographic appearance of occipital haemangioma simulating encephalocele.

Encephalocele is the most common cause of occipital midline extracranial mass associated with hydrocephalus. A case is presented where an occipital extracranial mass associated with hydrocephalus which was detected on second-trimester ultrasound examination turned out to be a haemangioma, a relatively benign lesion. We suggest that haemangioma should be considered in the differential diagnosis of extracranial masses detected prenatally.


Morphological features of a case of retinoic acid embryopathy.

A case of retinoic acid embryopathy which was retrospectively diagnosed after delivery is presented. The affected fetus was exposed to the drug during the first month of pregnancy and second-trimester sonographic examination showed hydrocephalus and cardiac malformation. The diagnosis was made on the basis of autopsy findings and genetic enquiry.


Prenatal application of fluorescent in situ hybridization (FISH) for identification of a mosaic Y-chromosome marker, idic(Yp).

An amniocentesis was performed at 13.3 weeks' gestation for advanced maternal age. A mosaic sex chromosome pattern was found: of 50 cells examined, 34 had a 45,X karyotype. In 14 cells with a modal number of 46, a recognizable Y was substituted by a small non-fluorescent marker. C-banding identified the marker as an isodicentric in 12 cells. In two cells, the non-fluorescent marker appeared to be monocentric and looked like a non-fluorescent del (Yq), but could have been an isodicentric Y with inactivation of one of the centromeres. Two cells with a modal number of 47 showed two copies of the monocentric marker. Fluorescent in situ hybridization with an alpha satellite Y-specific centromeric probe confirmed the Y-chromosome origin of the markers and allowed for more accurate prenatal diagnostic information.


Diagnosis and prenatal diagnosis of epidermolysis bullosa herpetiformis (Dowling-Meara) in a mother, two affected children, and an affected fetus.

In utero skin biopsy was performed on a fetus at risk of an uncertain form of epidermolysis bullosa (EB). The mother had produced two affected offspring diagnosed variously as having junctional or dystrophic EB. The two offspring and the fetus were products of different fathers. The mother claimed to have no disease and on clinical examination was without blisters. Examination of the fetal skin biopsy by light and electron microscopy revealed separation of the epidermal sheet from the majority of the biopsy sample, although occasional remnants of basal cells remained associated with the basement membrane. Aggregations of keratin filaments were observed within basal cells of the detached epidermis and in the attached basal cell remnants. The diagnosis was thus suggested to be epidermolysis bullosa Dowling-Meara. Re-review of the clinical and laboratory data from the affected infants revealed a clinical and histological pattern consistent with this diagnosis. Further discussion with the mother revealed that her skin had blistered as a child and that she presently had hyperkeratotic palms and soles. This history is consistent with the autosomal dominantly inherited epidermolysis bullosa herpetiformis (Dowling-Meara). This is the first reported prenatal diagnosis of EB Dowling-Meara. The morphological criteria of intraepidermal blistering and clumped keratin filaments within basal and immediately suprabasal cells characteristic of an affected individual postnatally also identified an affected fetus. There is, however, insufficient experience to be certain that these findings will hold from region to region in the body or among all affected fetuses, and thus prenatal diagnosis on a morphological basis should still be made with caution.


Fetal nuchal fluid--physiological or pathological?--In pregnancies less than 17 menstrual weeks.

For pregnancies less than 17 menstrual weeks, increasing amounts of nuchal fluid increase the risks of chromosome abnormalities with localized nuchal fluid, diffuse nuchal fluid, cystic hygroma, and fetal hydrops having chromosomal risks of 12, 23, 50, and 78 per cent, respectively. The ultrasound appearance of localized or diffuse nuchal fluid is not a specific discriminator, but a fluid depth of greater than or equal to 5 mm may be an indicator of increased risk of fetal chromosomal abnormalities. If the fluid depth is less than 5 mm, there is a stronger negative predictive value and negative likelihood risk of a fetal chromosome abnormality. Gestational age did not improve the fluid depth predictive value. Differentiation of physiological from pathological requires chromosome analysis, serial ultrasound evaluation, and good clinical examination as a newborn and possibly as a young child. Long-term follow-up of those cases identified with resolving nuchal fluid abnormalities is not available and is required for a complete understanding of physiological and pathological aetiologies. Genetic counselling for fetal nuchal fluid would be recommended.


Prenatal diagnosis in a family with X-linked chronic granulomatous disease with the use of the polymerase chain reaction.

In the X-linked form of chronic granulomatous disease (X91 degrees CGD), the genetic defect is linked to the CYBB locus on the X chromosome. We studied a family with a genetic defect in this gene, consisting of a G----A substitution at the fifth base of the 5' donor splice site of intron 3. This mutation leads to skipping of exon 3 after transcription of the gene. The expectant mother was diagnosed as a carrier. Analysis of polymerase chain reaction (PCR)-amplified genomic DNA from a chorionic villus biopsy (CVB) showed the same mutation in the male fetus. After termination of the pregnancy, the diagnosis was confirmed by conventional methods. This is the first time that PCR has been used for prenatal diagnosis of CGD.


Maternal serum CA 125 for aneuploidy detection in early pregnancy.

Maternal serum CA 125 levels were determined at 9-11 menstrual weeks for 26 cases of trisomy 13 (n = 4), trisomy 18 (n = 7), trisomy 21 (n = 15), and appropriate controls. There were no statistically significant differences between groups.


The chemical composition and nutritional potential of the tribal pulse, Abrus precatorius L.

The boiled seeds of Abrus precatorius L. are eaten by the residents of the Andaman Islands in India. The seeds were analysed for proximate composition, total (true) protein, seed protein fractions, amino acid profile of seed proteins, minerals and certain antinutritional factors. The seed proteins are rich in most of the essential amino acids, and they are deficient only in cystine and threonine, when compared to the WHO/FAO requirement pattern. The antinutritional factors (total free phenols, tannins, trypsin inhibitor activity and haemagglutinating activity) were also investigated.


Sensory evaluation of and acceptability trials on biscuits prepared from raw and malted wheat (Triticum aestivum)-Bengal gram (Cicer arietinum) mixes with or without a green leafy vegetable.

Biscuits were prepared by varying the amounts of the basic ingredients to arrive at the most acceptable recipe. The final recipe contained 40 g of mix, 40 g of jaggery and 20 g of ghee. Sensory evaluation of biscuits containing 5 or 10% colocasia leaf powder by composite scoring test and hedonic scale showed that the former type of biscuit was preferred over the latter. The acceptability trial conducted on 42, 3 to 6 year old children showed that biscuits from either malted mix with or without 7.5% colocasia leaf powder and raw mix were equally acceptable as shown by the analysis of variance.


Microorganisms associated with natural fermentation of Prosopis africana seeds for the production of okpiye.

Okpiye is a food condiment prepared by the fermentation of Prosopis africana seeds. The traditional process for the production and microbiological characteristics of the condiment were investigated. During laboratory fermentation that lasted 96 h, the mesquite seeds underwent a natural fermentation that was characterised by the growth of microorganisms to 10(6)-10(8) cfu/g. Several species of bacteria especially B. subtilis, B. licheniformis, B. megaterium, Staphylococcus epidermidis and Micrococcus spp were found to be the most actively involved organisms. However, significant contributions to the microbial ecology were made by Enterobacter cloacae and Klebsiella pneumoniae. Lactobacillus spp were present in low numbers towards the end of the fermentation. The presence of Proteus and Pseudomonas spp in traditional fermented samples demonstrate the variability which may exist in the microflora of individual fermented samples. Variations in the important microbial groups show that Bacillus spp were the most prevalent species and occurred until the end of fermentation. Temperature, pH and titratable acidity varied with time and were influenced by the metabolic activities of the microorganisms.


Radiation effect on ascorbic acid and riboflavin biosynthesis in germinating soybean.

The influence of irradiation on biosynthesis of ascorbic acid and riboflavin in germinating soybean seeds in tap and distilled water at ambient (25-35 degrees C) conditions was investigated. Ascorbic acid was not detectable in the original seeds and the initial level of riboflavin was 3.3 micrograms/g. The rate of synthesis of these vitamins increased with increasing germination time up to 72-96 hr followed by a decreasing pattern depending upon the treatment. The effect of irradiation and germination on the synthesis of these vitamins was statistically significant (P less than 0.01). Maximum amounts of ascorbic acid 16.2 and 15.0 mg/100g (fresh weight basis) were found in the 0.10 kGy sample after 72 hr of germination in tap and distilled water, respectively. However, a radiation dose of 0.20 kGy resulted in the development of maximum values of riboflavin, 30.0 and 27.0 micrograms/g (dry weight basis) on germination in tap and distilled water respectively.


Bio-availability of iron from spinach (Spanicia oleracea) cultivated in soil fortified with graded levels of iron.

In vitro availability of iron along with ascorbic acid, oxalic acid and phosphorus contents of two varieties of spinach (Pusa Jyoti and Allgreen) cultivated in soil with different levels of added iron was determined. Addition of graded levels of iron to soil markedly increased the total iron and phosphorus contents and significantly decreased the bio-availability of iron, ascorbic acid and oxalic acid contents of spinach. Ascorbic acid and oxalic acid contents markedly exerted a positive influence while phosphorus exerted a negative influence on the bio-availability of iron.


The effects of sprouting times on nutritive value of two varieties of African yam bean (Sphenostylis stenocarpa).

Forty-eight rats (80-125 g) were used to determine the nutritive value of two sprouted varieties of African yam bean. The cream and brown varieties were each sprouted for 36, 48 and 72 h and blended with corn in a 70:30 ratio (protein basis) to provide 1.6 g N/100 g diet for the entire study period. Sprouting for 48 h caused an increase in most of the parameters tested for both varieties. Sprouting increased natural enhancement of nutrients.


Nutritional and chemical evaluation of raw seeds of Canavalia gladiata (Jacq) DC. and C. ensiformis DC: the under utilized food and fodder crops in India.

In India, the seeds of Canavalia gladiata and C. ensiformis have traditionally been eaten by the aborigines, but they are less popular among the civilized people. The data on the chemical composition and nutritional quality of these seeds are not readily available. The proximate composition, mineral composition, the contents of total (true) proteins, seed protein fractions, profile of seed protein amino acids and certain antinutritional factors were analysed and reported in the present study. The seeds of C. ensiformis contain more crude protein, crude lipid and minerals like Na, K, Ca, Mg, P, Fe and Mn than does C. gladiata. Both albumins and globulins together constitute the major bulk of seed proteins. In both the species of Canavalia investigated, glutamic acid, aspartic acid, isoleucine + leucine, tyrosine + phenylalanine and lysine are the major amino acids of seed proteins. The presence of certain antinutritional factors (total free phenols, tannins, lectins, L-DOPA, trypsin inhibitor activity) is also reported for both species of Canavalia.