The effect of drugs on the electrical and mechanical activity of the isolated porcine stomach.

Electrical and mechanical activity was recorded from totally isoltted porcine stomachs perfused with homologous blood, The electrical control activity, response activity, and mechanical reaction to various hormones and drugs stimulationg these activities were recorded. The drugs were injected directly into the gastric artery of the isolated organ. Normal response to cholinergic stimulants and to pentagastrin was observed. The effect of blockers such as atropine, hexamethonium and tetrodotosin on the action of stimulants was also assessed. The results of this study suggest that the release of acetylcholine is involved in the mechanism of action of pentagastrin. They also demonstrate the usefulness of the isolated porcine stomach approach to the study of gastric myoelectrical and mechanical activity.     

Polymorphic CAG repeat length in the androgen receptor gene and association with neurodegeneration in a heterozygous female carrier of Kennedy’s disease

Kennedy's disease (spinobulbar muscular atrophy) is an X-linked form of motor neuron disease affecting adult males carrying a CAG trinucleotide repeat expansion within the androgen receptor gene. While expression of Kennedy's disease is thought to be confined to males carrying the causative mutation, subclinical manifestations have been reported in a few female carriers of the disease. The reasons that females are protected from the disease are not clear, especially given that all other diseases caused by CAG expansions display dominant expression. In the current study, we report the identification of a heterozygote female carrying the Kennedy's disease mutation who was clinically diagnosed with motor neuron disease. We describe analysis of CAG repeat number in this individual as well as 33 relatives within the pedigree, including two male carriers of the Kennedy's mutation. The female heterozygote carried one expanded allele of the androgen receptor gene with CAG repeats numbering in the Kennedy's disease range (44 CAGs),with the normal allele numbering in the uppernormal range (28 CAGs). The subject has two sons, one of whom carries the mutant allele of the gene and has been clinically diagnosed with Kennedy's disease, whilst the other son carries the second allele of the gene with CAGs numbering in the upper normal range and displays a normal phenotype. This coexistence of motor neuron disease and the presence of one expanded allele and one allele at the upper limit of the normal range may be a coincidence. However, we hypothesize that the expression of the Kennedy's disease mutation combined with a second allele with a large but normal CAG repeat sequence may have contributed to the motor neuron degeneration displayed in the heterozygote female and discuss the possible reasons for phenotypic expression in particular individuals.     

Opposite reaction of ERK and JNK in ischemia vulnerable and resistant regions of hippocampus: involvement of mitochondria

Delayed ischemic death of neurones is observed selectively in CA1 region of hippocampus at 3-4 days of reperfusion. Signals generated immediately during and after ischemia are further propagated by a variety of kinases, proteases and phosphatases. Tissue samples from dorsal (vulnerable) and abdominal (resistant) parts of gerbil hippocampi were collected to determine the activation state of key signaling molecules: Akt, Raf-1, JNK, ERK1/2 in the course of reperfusion after 5 min of global cerebral ischemia. Western blot analysis of phosphorylated forms of the kinases revealed persistent activation of JNK, being limited mostly to vulnerable CA1 region. On the contrary, activation of ERK, although observed transiently in both parts, was enhanced for a longer time in the abdominal hippocampus. The levels of the active/phosphorylated Akt and Raf-1 kinases did not change significantly during the recovery period. No significant correlation between postischemic JNK activation and c-Jun phosphorylation or its contribution to AP1-like complex formation was found. In contrast, the amount of active JNK linked with mitochondrial membranes was significantly increased and preceded neuronal death in CA1. In the same period of time the AP1 complex, augmented in CA1 region, did not appear to contain a classical c-Fos protein. These results are consistent with the theory that either long-lasting activation of JNK and/or contrasting ERK and JNK activities in critical time of reperfusion, contribute to selective apoptosis of CA1 neurons. This, in connection with the translocation of activated JNK to mitochondria and time/regional differences in AP1 binding protein complexes can affect final postischemic outcome.     

Immunogenicity of nonreplicating recombinant vaccinia expressing HLA-A201 targeted or complete MART-1/Melan-A antigen

The effect on immunogenicity of different tumor T cell epitope formulations was evaluated in vitro using nonreplicating recombinant vaccinia vector expressing two forms of the melanoma-associated MART-1/Melan-A antigen. The first recombinant virus expressed a minigene encoding a fusion product between an endoplasmic reticulum (ER)-targeting signal and the HLA-A201 binding 27-35 peptide. The second viral construct encoded the complete MART-1/Melan-A protein. The capacity of HLA-A201 cells infected with either viral construct to generate and to stimulate MART-1/Melan-A 27-35 specific cytotoxic T-lymphocytes (CTL), was comparatively characterized. The results obtained here with a tumor antigen confirmed the capacity of vaccinia virus-encoded ER-minigene to generate a very strong antigenic signal. In cytotoxicity assays, recognition of target cells infected with high amounts of both recombinant viruses with activated specific CTL clones, resulted in similar lytic activity. With regard to calcium mobilization, TCR down-regulation, IFN-gamma release, and T cell proliferation assays, the targeted epitope elicited 10- to 1000-fold stronger responses. Remarkably, the immunogenic difference between the two formulations, in their respective capacity to generate CTL from naive HLA-A2 peripheral blood mononuclear cells in vitro as measured by tetramer detection, was lower (2- to 3-fold). Recombinant vectors expressing complete antigens have demonstrated their capacity to generate specific responses and such vaccines might take advantage of a broader potential of presentation. However, as demonstrated here for the HLA-A201-restricted MART-1/Melan-A immunodominant epitope, nonreplicative vaccinia virus expressing ER-targeted minigenes appear to represent a significantly more immunogenic epitope vaccine formulation.     

Stability of cefotaxime sodium in solid state

The influence of temperature and relative humidity on the stability of cefotaxime sodium in the solid state was investigated. Changes in the concentration of cefotaxime sodium were followed by a HPLC method with UV detection. The kinetic and thermodynamic parameters of the decomposition reaction were calculated.     

Severe subfertility in mice with androgen receptor inactivation in sex accessory organs but not in testis

Androgen action on sex accessory organs influences rodent fertility, but the mechanisms remain unclear and investigation is difficult without the ability to restrict androgen action in specific tissues. We used Cre-LoxP technology to generate male mice with prostate epithelial-specific androgen receptor deficiency (denoted PEARKO). In addition to prostate, these males have reduced androgen action due to tissue-selective androgen receptor inactivation in seminal vesicle, epididymis, and vas deferens, whereas the testis is unaffected. We find that fertility of PEARKO males was severely reduced, compared with littermates with prominent defects in copulatory plug formation, which were smaller, softer, and more friable than controls. Despite normal testis sperm production, sperm numbers were reduced in caput but increased in cauda epididymis, suggesting alterations in sperm epididymal transit kinetics associated with increased rate of spontaneous acrosome reaction and abnormal flagellar morphology in PEARKO cauda epididymal sperm. Whereas the quantitative in vitro fertilizing ability of PEARKO epididymal sperm was normal, fewer fertilized oocytes were flushed from the oviducts of females after natural mating with PEARKO males. These data show that sperm formed in mice with impaired androgen action restricted to accessory glands and epididymis are quantitatively normal in number and in vitro fertilizing function but that severe in vivo subfertility reflects other functions related to sperm transport and survival in female reproductive tract that determine fertility in vivo.     

The Effects of Vitamin D-Enriched Mushrooms and Vitamin D3 on Cognitive Performance and Mood in Healthy Elderly Adults: A Randomised,Double-Blinded,Placebo-Controlled Trial

Despite abundant cross-sectional evidence that low vitamin D status is associated with risk of cognitive decline in ageing, interventional evidence for benefits of vitamin D supplementation is lacking. This study was a 6 month randomised, double-blinded placebo-controlled clinical trial of the effects of vitamin D3 (D3), enhanced vitamin D2 in a mushroom matrix (D2M), standard mushroom (SM) and placebo (PL) on cognition and mood in n = 436 healthy older male (49%) and female volunteers aged ≥ 60 years. Primary end points were change in serum vitamin D metabolites (25-OH-D, 25-OH-D2 and 25-OH-D3), cognitive performance, and mood over 24 weeks. Levels of total 25-OH-D and 25-OH-D3 were maintained in the D3 arm but decreased significantly (p < 0.05) in the remaining arms (D2M, SM and PL). Analysis also revealed differential changes in these metabolites depending on total vitamin D status at baseline. There were no significant effects of treatment on any of the measures of cognitive function or mood. Overall, the results show that daily supplementation of ~600 IU of vitamin D3 was sufficient to maintain 25-OH-D throughout winter months, but in contrast to existing cross-sectional studies there was no support for benefit of vitamin D supplementation for mood or cognition in healthy elderly people.     

The stability of cefprozil in oral suspension CEFZIL

The stability of cefprozil in oral suspension CEFZIL was studied by means of the stress stability test. Degradation was evaluated by using an HPLC method with UV detection (280 nm), as described in the monograph of Cefprozil for Oral Suspension, in USP 25. At increased temperature and relative air humidity the degradation of cefprozil in CEFZIL occurs as reversible-consecutive and parallel reactions. The reversible reaction of isomerization is approx. 10 times faster than the parallel degradation reaction of individual isomers. The first-order rate constants of the parallel reactions Z-cefprozil --> product 1 and E-cefprozil --> product 2 were determined at RH = 76.4% at T = 333, 338, 343, 348 and 353 K, and at T = 333 K and RH = 50.9, 66.5, 76.4 and 90.0%. The thermodynamic parameters E(a), deltaH(double dagger) and deltaS(double dagger) of these reactions were calculated.