Prenatal valproic acid exposure disrupts tonotopic c-Fos expression in the rat brainstem.

Autism spectrum disorder (ASD) is a group of neurodevelopmental conditions characterized by difficulties in communication and social interactions, restricted, repetitive behaviors and sensory abnormalities. Notably, the vast majority of individuals with ASD experience some degree of auditory dysfunction and we have recently reported consistent hypoplasia and dysmorphology in auditory brainstem centers in individuals with ASD. Prenatal exposure to the antiepileptic drug valproic acid (VPA) is associated with an increased risk of ASD. In rodents, prenatal exposure to VPA is employed as an animal model of ASD and is associated with a number of anatomical, physiological and behavioral deficits, including hypoplasia and dysmorphology of auditory brainstem centers. Based on these observations, we hypothesized that such dysmorphology in VPA-exposed animals would translate into abnormal neuronal activity in brainstem circuits and irregular tonotopic maps. Herein, we have subjected control and VPA-exposed animals to 4- or 16-kHz tones and examined neuronal activation with immunohistochemistry for c-Fos. After these exposures, we identified significantly more c-Fos-positive neurons in the auditory brainstem of VPA-exposed animals. Additionally, we observed a larger dispersion of c-Fos-positive neurons and shifted tonotopic bands in VPA-exposed rats. We interpret these findings to suggest hyper-responsiveness to sounds and disrupted mapping of sound frequencies after prenatal VPA exposure. Based on these findings, we suggest that such abnormal patterns of activation may play a role in auditory processing deficits in ASD.

Prenatal valproic acid exposure disrupts tonotopic c-Fos expression in the rat brainstem.

Autism spectrum disorder (ASD) is a neurodevelopmental condition characterized by difficulties with communication and social interactions, restricted, repetitive behaviors and sensory abnormalities. Additionally, the vast majority of subjects with ASD suffer some degree of auditory dysfunction and we have previously identified significant hypoplasia and dysmorphology in auditory brainstem centers in individuals with ASD. Prenatal exposure to the antiepileptic drug valproic acid (VPA) is associated with an increased risk of ASD. In rodents, prenatal exposure to VPA is utilized as an animal model of ASD and is associated with a number of anatomical, physiological and behavioral deficits, including hypoplasia and dysmorphology in the auditory brainstem. Based on these observations, we hypothesized that such dysmorphology in VPA-exposed animals would translate into abnormal activity in brainstem circuits and irregular tonotopic maps. Herein, we have subjected control and VPA-exposed animals to 4 or 16 kHz tones and examined neuronal activation with immunohistochemistry for c-Fos. After these sound exposures, we found significantly more c-Fos-positive neurons in the auditory brainstem of VPA-exposed animals. Further, we found a larger dispersion of c-Fos-positive neurons and shifted tonotopic bands in VPA-exposed rats. We interpret these findings to suggest hyper-responsiveness to sounds and disrupted mapping of sound frequencies after prenatal VPA exposure. Based on these findings, we suggest that such abnormal patterns of activation may play a role in auditory processing deficits in ASD.

Effects of the inclusion of Equex STM into Tris-based extender on the motility of dog spermatozoa incubated at 5 degrees C.

The aim of this study was to estimate the effects of Equex STM on sperm motion characteristics in chilled dog semen extended in Tris-based diluent. Thirty-two ejaculates were collected from 12 proven German shepherd stud dogs. The sperm-rich fractions were diluted in Tris-based extender with 1% (v/v) Equex STM (sample A) and in Tris-based extender with no addition of detergent (sample B). The extended semen was incubated for 240 h at 5 degrees C and the motility parameters were evaluated by CASA system at 24-h intervals. Addition of Equex STM to Tris-based extender led to an initial activation of motion activity of spermatozoa, followed by a rapid decrease, shortening the lifespan of spermatozoa incubated at 5 degrees C. Computer-assisted sperm analysis clearly showed that Equex STM-induced changes of sperm motion characteristics resemble the hyperactivation (HA) of spermatozoa associated with the capacitation process.

Chromosome instability in a calf with amelia of thoracic limbs.

We report here on a case of a Holstein-Friesian male calf with the congenital total absence of thoracic limbs (amelia). Cytogenetic study showed a high rate of chromosome instability, represented by chromosome or chromatid breaks and gaps in 46% of the analyzed metaphase spreads. Moreover, 12% of the spreads appeared to be polypolid. The number of micronuclei also was significantly higher when compared to control animals. This paper discusses the association between chromosome instability and limb malformation.

Effect of collection frequency on quantitative and qualitative characteristics of pigeon (Columba livia) semen.

The aim was to estimate the optimal frequency of semen collection from pigeons in relation to ejaculate volume, sperm concentration, total spermatozoa in ejaculate and percentage of live morphologically normal cells. The study was carried out on 455 ejaculates collected from two groups of pigeons, each of 10 males (group I: meat-type breed; group II: fancy pigeon). The birds were selected and kept individually in cages under a natural photoperiod. A two-person technique was used for semen collection (lumbo-sacral and cloacal region massage). Semen was collected once, twice or three times per week. Colour, consistency and volume of ejaculates were evaluated macroscopically immediately after collection. Sperm concentration and total number of cells in the ejaculate were estimated after dilution with Ringer's solution. A live-dead stain technique (nigrosin-eosin) was used to determine the percentage of live and normal spermatozoa. Semen collected 3x/week was of high quality. The average volume of a single ejaculate was small (21 microl in group I and 19 microl in group II), but sperm concentration was high--1.58 x 10(9)/ml and 1.96 x 10(9)/ml, respectively. The mean number of spermatozoa per ejaculate was 30.48 x 10(6) in group I and 39.49 x 10(6) in group II. An increased percentage of live and normal spermatozoa in semen collected more frequently was also observed. Collecting pigeon semen 3x/week provides spermatozoa in larger amounts and of better quality than less frequent collections (1x/week or 2x/week) and is recommended for obtaining more insemination doses.

A 12-amino-acid segment, present in type s2 but not type s1 Helicobacter pylori VacA proteins, abolishes cytotoxin activity and alters membrane channel formation.

Helicobacter pylori, a gram-negative bacterium associated with gastritis, peptic ulceration, and gastric adenocarcinoma in humans, secretes a protein toxin, VacA, that causes vacuolar degeneration of epithelial cells. Several different families of H. pylori vacA alleles can be distinguished based on sequence diversity in the "middle" region (i.e., m1 and m2) and in the 5' end of the gene (i.e., s1 and s2). Type s2 VacA toxins contain a 12-amino-acid amino-terminal hydrophilic segment, which is absent from type s1 toxins. To examine the functional properties of VacA toxins containing this 12-amino-acid segment, we analyzed a wild-type s1/m1 VacA and a chimeric s2/m1 VacA protein. Purified s1/m1 VacA from H. pylori strain 60190 induced vacuolation in HeLa and Vero cells, whereas the chimeric s2/m1 toxin (in which the s1 sequence of VacA from strain 60190 was replaced with the s2 sequence from strain Tx30a) lacked detectable cytotoxic activity. Type s1/m1 VacA from strain 60190 formed membrane channels in a planar lipid bilayer assay at a significantly higher rate than did s2/m1 VacA. However, membrane channels formed by type s1 VacA and type s2 VacA proteins exhibited similar anion selectivities (permeability ratio, P(Cl)/P(Na) = 5). When an equimolar mixture of the chimeric s2/m1 toxin and the wild-type s1/m1 toxin was added to HeLa cells, the chimeric toxin completely inhibited the activity of the s1/m1 toxin. Thus, the s2/m1 toxin exhibited a dominant-negative phenotype similar to that of a previously described mutant toxin, VacA-(Delta6-27). Immunoprecipitation experiments indicated that both s2/m1 VacA and VacA-(Delta6-27) could physically interact with a c-myc epitope-tagged s1/m1 VacA, which suggests that the dominant-negative phenotype results from the formation of heterooligomeric VacA complexes with defective functional activity. Despite detectable differences in the channel-forming activities and cytotoxic properties of type s1 and type s2 VacA proteins, the conservation of type s2 sequences in many H. pylori isolates suggests that type s2 VacA proteins retain an important biological activity.

Antigenic diversity among Helicobacter pylori vacuolating toxins.

Helicobacter pylori vacuolating cytotoxin (VacA) is a secreted protein that induces vacuolation of epithelial cells. To study VacA structure and function, we immunized mice with purified type s1-m1 VacA from H. pylori strain 60190 and generated a panel of 10 immunoglobulin G1kappa anti-VacA monoclonal antibodies. All of the antibodies reacted with purified native VacA but not with denatured VacA, suggesting that these antibodies react with conformational epitopes. Seven of the antibodies reacted with both native and acid-treated VacA, which suggests that epitopes present on both oligomeric and monomeric forms of the toxin were recognized. Two monoclonal antibodies, both reactive with epitopes formed by amino acids in the carboxy-terminal portion of VacA (amino acids 685 to 821), neutralized the cytotoxic activity of type s1-m1 VacA when toxin and antibody were mixed prior to cell contact but failed to neutralize the cytotoxic activity of type s1-m2 VacA. Only 3 of the 10 antibodies consistently recognized type s1-m1 VacA toxins from multiple H. pylori strains, and none of the antibodies recognized type s2-m2 VacA toxins. These results indicate that there is considerable antigenic diversity among VacA toxins produced by different H. pylori strains.

Effects of three cryopreservation methods and two semen extenders on the quality of dog semen after thawing.

The aim of this study was to evaluate the influence of two diluents, one with and the other without Orvus ES paste, and three methods of cryopreservation on the quality of dog semen after thawing. The investigation was carried out on 126 ejaculates collected from 37 dogs. In Expt 1, sperm-rich fractions of ejaculates were frozen in 0.25 ml minitubes and pellets. In Expt 2, each sperm-rich fraction of ejaculate was divided and extended in two diluents, one with and the other without Orvus ES paste. Samples of semen were frozen in pellets and 0.5 ml French straws. Motility, percentage of spermatozoa with normal acrosomes and longevity of spermatozoa were significantly higher (P < 0.05) in semen samples frozen in pellets than in samples frozen in 0.25 ml minitubes. Aspartate aminotransferase activity in extracellular fluid was significantly (P < 0.05) lower in semen frozen in pellets. There were no significant differences in quality after thawing between semen samples frozen in pellets and 0.5 ml French straws. Longevity, unlike acrosome status and aspartate aminotransferase activity, was greater in samples extended in Tris-buffered diluent with addition of Orvus ES paste, regardless of the method of cryopreservation.

A dominant negative mutant of Helicobacter pylori vacuolating toxin (VacA) inhibits VacA-induced cell vacuolation.

Most Helicobacter pylori strains secrete a toxin (VacA) that causes structural and functional alterations in epithelial cells and is thought to play an important role in the pathogenesis of H. pylori-associated gastroduodenal diseases. The amino acid sequence, ultrastructural morphology, and cellular effects of VacA are unrelated to those of any other known bacterial protein toxin, and the VacA mechanism of action remains poorly understood. To analyze the functional role of a unique strongly hydrophobic region near the VacA amino terminus, we constructed an H. pylori strain that produced a mutant VacA protein (VacA-(Delta6-27)) in which this hydrophobic segment was deleted. VacA-(Delta6-27) was secreted by H. pylori, oligomerized properly, and formed two-dimensional lipid-bound crystals with structural features that were indistinguishable from those of wild-type VacA. However, VacA-(Delta6-27) formed ion-conductive channels in planar lipid bilayers significantly more slowly than did wild-type VacA, and the mutant channels were less anion-selective. Mixtures of wild-type VacA and VacA-(Delta6-27) formed membrane channels with properties intermediate between those formed by either isolated species. VacA-(Delta6-27) did not exhibit any detectable defects in binding or uptake by HeLa cells, but this mutant toxin failed to induce cell vacuolation. Moreover, when an equimolar mixture of purified VacA-(Delta6-27) and purified wild-type VacA were added simultaneously to HeLa cells, the mutant toxin exhibited a dominant negative effect, completely inhibiting the vacuolating activity of wild-type VacA. A dominant negative effect also was observed when HeLa cells were co-transfected with plasmids encoding wild-type and mutant toxins. We propose a model in which the dominant negative effects of VacA-(Delta6-27) result from protein-protein interactions between the mutant and wild-type VacA proteins, thereby resulting in the formation of mixed oligomers with defective functional activity.

The effect of administration of a beta blocker in periparturient mares.

This study investigated the effect of a beta blocker on parturition, fetal membrane retention and subsequent fertility in mares. The animals were divided into an experimental group (150 mares treated during second stage labour with propranolol [50 mg i.v.]) and a control group (180 mares with no treatment). Administration of propranolol was associated with a significant decrease in time of expulsion of fetal membranes, and an increase in both exhibition of foal heat and pregnancy rates at this heat.

Social and geographical risk factors in Helicobacter pylori infection.

A correlation between childhood crowding and the later development of gastric cancer has been demonstrated by Barker and colleagues, who proposed that the relationship was the consequence of infection by an organism such as Helicobacter pylori. In order to test this hypothesis the presence of IgG antibodies to H. pylori in sera from blood donors in North Wales has been investigated. During donation sessions, donors answered questions relating to social conditions and domicile in childhood (at age 10 years) and adult life (the preceding 2 years). A stepwise logistic regression analysis of the data demonstrated significant independent relationships between seropositivity and the following factors: sharing a bed in childhood, housing density, locality of birth, adult social class and age.

Wiskott-Aldrich syndrome. A case report.

This paper presents a report on a child with Wiskott-Aldrich syndrome. The clinical picture and laboratory findings are characteristic of this disease. The prevailing symptoms have included recurrent respiratory and alimentary tract infections, seborrhic dermatitis-type skin lesions, and thrombocytopenia. Humoral and cellular immunological disturbances have been noted, and the pedigree pattern is very characteristic.

[Effect of adrenergic drugs and exploitation on sexual reflexes and semen properties in Polish large white boars aged 2-3 years]. / Wplyw leków ukladu adrenargicznego i eksploatacji na odruchy plciowe i wlasciwosci nasienia knurów rasy wbp w wieku 2-3 lat.

The effect of exploitation and adrenergic system drugs on sexual reflexes and properties of the semen in somatically mature Polish Large White boars has been presented. At the first stage 8 males were exploited twice a week. Then, previous to semen collection, the animals were given beta-adrenolytic (Propranolol--Polfa), after 30 minutes followed by the preparation Levonor--Polfa (alpha-adrenomimetic). 15 minutes after last injection the semen was collected, this procedure having been repeated twice a week. At the second stage of the experiment the same males were exploited once a week. Like in the first stage, the animals were given the same doses of the drugs in the same sequence. 15 minutes after last injection the semen was collected once a week. At the third stage of the experiment the boars were exploited every day. Again, like in the previous stages, the animals were given the above mentioned beta-adrenolytic and alpha-adrenomimetic to collect the semen 15 minutes after last injection. In all the stages of the experiment 6-8 ejaculates were collected from each boar. Apart from preliminary assessment of concentration and morphology of spermatozoons there was determined the level of protein and activity of selected enzymes in the semen. The sexual drive as well as the time of searching reflex and ejaculation were observed. The drugs applied have been proved to be able to prolong the time of ejaculation reflex. Simultaneous application of beta-adrenolytic and alpha-adrenomimetic to animals exploited twice a week appeared to increase the number of spermatozoons in the whole ejaculate, the percentage of spermatozoons with proper movement and the activity of GGT and fucosidase. Intensive exploitation of a boar with parallel application of the preparations described bring about a gradual decrease in spermatozoons and protein in the ejaculate as well as in the activity of hyaluronidase in its plasma and in conversion to mg protein of semen plasma.

[Concentration of ions of selected trace elements in the ejaculates of boars after interruption of the flow of the secretion from the testes, epididymis and accessory sexual glands]. / Stezenie jonów wybranych pierwiastków sladowych w ejakulatach knurów po odcieciu doplywu wydzieliny jader, najadrzy i dodatkowych gruczolów plciowych.

The investigations were carried out on 6 boars aged from 10 to 12 months. Before operation, 5 ejaculates were collected from each animal. In the second stage of the investigations, the boars were subjected to the following procedures: the deferent ducts were cut and ligated, and the bulbo-urethral glands and vesicular glands were removed. Four to 28 ejaculates were collected after each operation. The ejaculates obtained at the individual stages of the experiments were subjected to the following tests: introductory assessment, concentration and morphology of spermatozoa, and biochemical investigations concerning the concentration of Mn, Co, Cd, Fe, Cr, Ni, Sr, Ag and Li. The authors proved that the secretions from the individual segments of the reproductive organ of the boar are different in respect of their biochemical composition. The secretion of the testicles and epididymides determines the concentration of Mn, Cd and Cr in the ejaculate of the animals. The level of Mn and Fe seems to be largely influenced by the secretion from the vesicular glands and deferent ducts. The secretion of the prostate and urethral glands is responsible for the level of Cr and Ni in semen plasma, and also for the concentration of Mn, Ca and Fe. The concentration of Fe in the semen of boars distinctly depends on the presence of spermatozoa and of the secretion of the bulbo-urethral glands. The AAS method failed to detect traces of Ag and Li in the ejaculates of these boars; Co was present in vestigial amounts only.

[Insemination of female rabbits]. / Obserwacje nad unasienianiem królic

The author's observations revealed that out of 20 female rabbits inseminated with undiluted semen, 18 animals got pregnant (90 per cent of the total). The insemination time ranged from 25 minutes to 5 hours and 30 minutes after the coitus with the sterile male. The volume of the insemination dose indispensable for pregnancy ranged from 0,2-0,6 ml, and the number of the spermatozoa with normal motility in that dose ranged from 27-30 million.