Synthesis of a Streptococcus pyogenes vaccine candidate based on the M protein PL1 epitope

Group A streptococcus is a Gram-positive bacteria that causes a range of infectious diseases. Targeting the bacteria, a new self-adjuvanting vaccine candidate, incorporating a carbohydrate carrier and an amino acid-based adjuvant, was synthesised utilising carbohydrate chemistry and solid-phase peptide synthesis procedures. Characterisation of the candidate was achieved using reverse-phase HPLC and electrospray ionisation mass spectrometry. The successful synthesis and characterisation of the vaccine candidate may contribute to the discovery of a therapeutically and clinically viable vaccine against group A streptococcus.     

Differences in prolyl-leucyl-glycinamide metabolism by hypothalamus,pituitary and cerebral cortex of male and female rats

l-Prolyl-l-leucyl-glycinamide is rapidly hydrolyzed by hypothalamic, hypophyseal and cortical homogenates from male or female rats. The peptidase activity is higher in the pituitary followed in decreasing order by the hypothalamus and the cerebral cortex. It is mostly localized in the supernatant fraction of a 100,000 g centrifugation and is inhibited by bacitracin.Tissues from female rats are half as active as those from male rats and show variations during the estrous cycle, with very low PLG metabolism at diestrus 1 in pituitary and hypothalamus. In contrast, the cerebral cortex at proestrus and estrus has significant lower hydrolyzing activity than at diestrus. No change of the peptidase activity is observed in tissues from ovariectomized animals after treatment with estrogen or progesterone.The results obtained suggest the existence of a correlation between peptidasic activity and melanotropin secretion.     

Patterns of Sleeping Site and Sleeping Tree Selection by Black-and-Gold Howler Monkeys (Alouatta caraya) in Northern Argentina

International Journal of Primatology - The selection of sleeping sites and sleeping trees in nonhuman primates is related to social and ecological factors. We investigate the role of body...     

Histopathological changes in susceptible corn inoculated with Helminthosporium maydis race O

Seedlings of a susceptible inbred line of male-fertile corn were inoculated with conidia of Helminthosporium maydis race O. Histological and ultrastructural observations of mesophyll, bundle sheath and phloem were made over a period of 8 days. Histological observations at 1 day revealed that lesions were comprised of several dead mesophyll cells bordered by a pair of vascular bundles. By 3 days lesions had developed their characteristic appearance caused by mesophyll collapse and had increased to a width of 10–12 bundles. At the ultrastructural level, the first signs of mesophyll cell change were rupture of the tonoplast and swelling of the mitochondrial matrix followed by a disintegration of the cytoplasm and swelling of the chloroplast stroma. Following these changes the cytoplasm became filled with an electron dense material and the plasmalemma ruptured leaving only partial remnants of chloroplasts as recognizable organelles. All of these changes occurred by 1 day. Bundle sheath cells were more resistant and intact cells could be observed in 3-day-old lesions. Phloem showed signs of degeneration by 1 day with distortion of the sieve-tube element membranes and disintegration of the companion cell cytoplasm. By 4 days the phloem had disintegrated.     

Hereditary central diabetes insipidus: plasma levels of antidiuretic hormone in a family with a possible osmoreceptor defect.

A large Canadian kindred of Irish extraction extending from Quebec to British Columbia with autosomal dominant diabetes insipidus responsive to exogenous antidiuretic hormone (ADH) is described. Out of 121 individuals 34 have been identified as affected in seven generations. The disorder is characterized by variability in age at onset and in severity, and by apparently spontaneous abatement in old age. The affected subjects do not appear to manifest hypertension or its sequelae. In three individuals tested the plasma ADH level was very low in spite of adequate osmotic stimulation. However, the level rose in two of them when they were given furosemide, which suggests an osmoreceptor defect and a normal ADH response to volume change.