Anatomical parameters of cardiopulmonary system in three different lines of chickens: further evidence for involvement in ascites syndrome.

The present study was designed to compare the anatomical parameters of the cardiopulmonary system in three different lines of chickens with different susceptibility to ascites syndrome. Eggs from three different genetic lines-commercial broiler and layer lines and one native to Iran--were incubated and hatched, and 1-day-old chicks used. The relative heart and lung weights, the volumes of the heart, lung and thorax cavity, the incidence of ascites, and the related physiological parameters in these chickens were followed. Lung weight as a percentage of body weight, the relative lung and heart volume, and the volumes of the thorax cavity, before and after removing heart and lung tissues, were lower in fast-growing broiler chickens compared with the layer and native chickens. Additionally, most of these parameters (e.g. relative lung weight, lung volume and thorax cavity) were significantly decreased with age in broiler chickens but were increased in layer and native chickens, which was concomitant with the incidence of ascites in broiler chickens. Our data indicate that all cardiopulmonary parameters investigated are extremely unfavourable to broiler chickens and suggest a reduction in gas exchange area in broilers, and therefore higher susceptibility to pulmonary hypertension and ascites.     

Hepatic DNA adduct dosimetry in rats fed tamoxifen: a comparison of methods

Liver homogenates from rats fed tamoxifen (TAM) in the diet were shared among four different laboratories. TAM-DNA adducts were assayed by high pressure liquid chromatography-electrospray tandem mass spectrometry (HPLC-ES-MS/MS), TAM-DNA chemiluminescence immunoassay (TAM-DNA CIA), and (32)P-postlabeling with either thin layer ((32)P-P-TLC) or liquid chromatography ((32)P-P-HPLC) separation. In the first study, rats were fed a diet containing 500 p.p.m. TAM for 2 months, and the values for measurements of the (E)-alpha-(deoxyguanosin-N(2)-yl)-tamoxifen (dG-N(2)-TAM) adduct in replicate rat livers varied by 3.5-fold when quantified using 'in house' TAM-DNA standards, or other approaches where appropriate. In the second study, rats were fed 0, 50, 250 or 500 p.p.m. TAM for 2 months, and TAM-DNA values were quantified using both 'in house' approaches as well as a newly synthesized [N-methyl-(3)H]TAM-DNA standard that was shared among all the participating groups. In the second study, the total TAM-DNA adduct values varied by 2-fold, while values for the dG-N(2)-TAM varied by 2.5-fold. Ratios of dG-N(2)-TAM:(E)-alpha-(deoxyguanosin-N(2)-yl)-N-desmethyltamoxifen (dG-N(2)-N-desmethyl-TAM) in the second study were approximately 1:1 over the range of doses examined. The study demonstrated a remarkably good agreement for TAM-DNA adduct measurements among the diverse methods employed.     

Reply to: sperm chromatin structural assay versus hypo-osmotic swelling test in predicting the need for in vitro fertilization with intracytoplasmic sperm injection

Sir, From Dr Check's Letter to the Editor (2004) the main questionis whether sperm chromatin structural assay (SCSA) can be usedas a prognostic tool in assisted reproduction technologies (ART)or not. From my point of view the research on this topic isstill in its early phase, in which typical problems such assmall study groups and     

Infantile hypotonia as a presentation of Rett syndrome

Rett syndrome (RTT) is classically defined by meeting certain clinical diagnostic criteria. It affects mostly females, and one possible pathogenic mechanism was considered to involve mitochondrial function. This was based on the finding of ultrastructural alterations in the mitochondria and decreased respiratory chain enzyme activity. However, the principal etiology of RTT has since been found to be mutations in the MECP2 gene, which is located on the X chromosome. Molecular analysis has allowed the phenotype of MECP2 mutations to be broadened beyond RTT to include girls who have mild mental retardation, autism, and an Angelman syndrome phenotype, as well as males with severe encephalopathy. We present a girl with a previously described mutation in the MECP2 gene whose phenotype is of atypical RTT. She presented with hypotonia and developmental delay in infancy without a clear period of normal development. As part of her evaluation for hypotonia, a muscle biopsy and respiratory chain enzyme analysis showed a slight decrease in respiratory chain enzyme activity consistent with previous reports. This report supports broadening the phenotype of patients who should be considered for MECP2 mutation analysis to include cases of developmental delay and hypotonia without evidence of an initial period of normal development. Furthermore, it supports the hypothesis of an underlying secondary defect in energy metabolism contributing to the pathogenesis of RTT.     

Ethical challenges related to elder care. High level decision-makers' experiences

Background  

Few empirical studies have been found that explore ethical challenges among persons in high public positions that are responsible for elder care. The aim of this paper was to illuminate the meaning of being in ethically difficult situations related to elder care as experienced by high level decision-makers.     

Induction of apoptosis of human primary osteoclasts treated with extracts from the medicinal plant <Emphasis Type="Italic">Emblica officinalis</Emphasis>

Background  

Osteoclasts (OCs) are involved in rheumatoid arthritis and in several pathologies associated with bone loss. Recent results support the concept that some medicinal plants and derived natural products are of great interest for developing therapeutic strategies against bone disorders, including rheumatoid arthritis and osteoporosis. In this study we determined whether extracts of Emblica officinalis fruits display activity of possible interest for the treatment of rheumatoid arthritis and osteoporosis by activating programmed cell death of human primary osteoclasts.     

The immunological consequences of gold therapy: a prospective study in patients with rheumatoid arthritis.

Gold sodium thiomalate (GST) is known to modify the disease process in patients with active rheumatoid arthritis (RA). To help understand the mechanism of action of GST, several immunological parameters were prospectively evaluated in 10 patients with active RA following the introduction of gold therapy. Before therapy, absolute numbers of peripheral blood T suppressor/cytotoxic lymphocytes were significantly depressed (P less than 0.01) and a raised T helper/T suppressor cell ratio was found. After 1 g of GST, an absolute reduction in total lymphocyte numbers including HLA/DR positive mononuclear cells, was evident (P less than 0.01). This lymphopenic effect was not selective for a single population since the proportions of T cells, T cell subsets and B cells remained unchanged. Lymphocyte function was also examined. Raised in vitro production of IgG (P less than 0.01) and IgA (P less than 0.05) was found before therapy. After GST, in vitro immunoglobulin synthesis was reduced and this was significant with respect to the IgM (P less than 0.001) and IgA (P less than 0.01) isotypes. Similarly, a parallel reduction in serum immunoglobulin levels developed. GST therapy was also associated with a reduced proliferative response to phytohaemagglutinin, concanavalin A and pokeweed mitogen in the initial phase of gold administration. The significant finding in this study suggest that the in vivo immunosuppressive effect of GST is explained not only by impaired mononuclear cell function but also by a significant reduction in T and B lymphocyte numbers.