The biochemical signatures of stress: A preliminary analysis of osteocalcin concentrations and macroscopic skeletal changes associated with stress in the 13th - 17th centuries black friars population.

OBJECTIVE: As a chemical precursor to the hard tissue changes well-studied in bioarchaeological research, osteocalcin provides a unique opportunity to assess stress via fluctuations in bone metabolism. The main objectives of this research were 1) to successfully extract osteocalcin from the Black Friars skeletal population; 2) to assess the diagenetic change between individual bone samples; and 3) to compare osteocalcin concentrations across sex, age, time period and macroscopic indicators of stress. METHODS: Twenty adult individuals were selected from the 13th-17th centuries Black Friars skeletal population with bone samples taken from the clavicle and femur. Total protein was assessed through a MicroBCA analysis with osteocalcin quantified using a Human Quantikine ELISA kit. Diagenetic change was assessed using Fourier transform infrared spectroscopy and the attenuated total reflectance method. RESULTS: Osteocalcin concentrations showed no significant differences between sex or age groups; however, between time period the post-medieval individuals showed a significant reduction of osteocalcin in both the clavicle and the femur. There were no significant differences in osteocalcin concentrations between those with and without past stress indicators and only one significant difference among the chronic indicators. The diagenetic results demonstrated a similar degree of crystallinity between all samples. CONCLUSIONS: While preliminary in nature, this study was successful in demonstrating the potential use of osteocalcin in future health-related research and how the study of osteocalcin may contribute to a better understanding of how and when stress begins to affect the skeletal tissues.

Cationic host defence peptides: innate immune regulatory peptides as a novel approach for treating infections.

An increase in antibiotic resistance and the emergence of new pathogens has led to an urgent need for alternative approaches to infection management. Immunomodulatory molecules that do not target the pathogen directly, but rather selectively enhance and/or alter host defence mechanisms, are attractive candidates for therapeutic development. Natural cationic host defence peptides represent lead molecules that boost innate immune responses and selectively modulate pathogen-induced inflammatory responses. This review discusses recent evidence exploring the mechanisms of cationic host defence peptides as innate immune regulators, their role in the interface of innate and adaptive immunity, and their potential application as beneficial therapeutics in overcoming infectious diseases.

Trypanosoma simiae and Trypanosoma congolense: surface glycoconjugates of procyclic forms-the same coats on different hangers?

Organic solvent extraction, reverse-phase high performance liquid chromatography and enzyme-linked immunosorbent assay with surface binding monoclonal antibodies were used to isolate membrane molecules of procyclic culture forms of Trypanosoma simiae and Trypanosoma congolense. Gel electrophoresis of the purified molecules revealed two predominant molecular species from each parasite that were broadly similar yet showed different apparent molecular masses and staining characteristics. The molecules were shown to be glycosylphosphatidylinositol-lipid anchored glycoconjugates, rich in carbohydrates. Each moiety displayed surface-disposed carbohydrate epitopes that were recognized on the surface of both species of trypanosomes by monoclonal antibodies specific for procyclic parasites of the subgenus Nannomonas. The epitopes were previously shown to be displayed on the glutamic acid-alanine rich protein of T. congolense yet neither this protein, nor its encoding gene is present in T. simiae. The results indicate that although T. congolense and T. simiae share common carbohydrate surface epitopes, these are displayed on biochemically different molecules. We speculate that the surface disposed carbohydrate structures are involved in parasite-tsetse interactions since these species have the same developmental cycles in the insect vector.

Phosphorylation of a major GPI-anchored surface protein of Trypanosoma brucei during transport to the plasma membrane.

The surface coat of procyclic forms of Trypanosoma brucei consists of related, internally repetitive glycoproteins known as EP and GPEET procyclins. Previously we showed that the extracellular domain of GPEET is phosphorylated. We now show that phosphorylation of this glycosylphosphatidylinositol-anchored surface protein can be induced in vitro using a procyclic membrane extract. Using antibodies that recognize either the phosphorylated or unphosphorylated form of GPEET, we analyzed their expression during differentiation of bloodstream forms to procyclic forms. Unphosphorylated GPEET, together with EP, was detected in cell lysates 2-4 hours after initiating differentiation whereas phosphorylated GPEET only appeared after 24 hours. Surface expression of EP and both forms of GPEET occurred after 24-48 hours and correlated with the detection of phosphorylated GPEET on immuno-blots. Electron micrographs showed that unphosphorylated GPEET was predominantly in the flagellar pocket whereas the phosphorylated form was distributed over the cell surface. In contrast, expression of a membrane-bound human placental alkaline phosphatase in procyclic forms caused the accumulation of dephosphorylated GPEET on the cell surface, while the phosphorylated form was restricted to the flagellar pocket. A GPEET-Fc fusion protein, which was retained intracellularly, was not phosphorylated. We propose that unphosphorylated GPEET procyclin is transported to a location close to or at the cell surface, most probably the flagellar pocket, where it becomes phosphorylated. To the best of our knowledge, this study represents the first localization of phosphorylated and unphosphorylated forms of a GPI-anchored protein within a cell.

Microbiological evaluation of women with bad obstetrics history.

In the present study a total of 300 pregnant women were evaluated, 200 women with bad obstetrics history (BOH) and 100 clinically normal women. Cervical culture studies, as well as serological evaluation was carried out in each woman. It was noted that among the various microbial agents detected, the presence of genital mycoplasmas, chlamydia, Toxoplasma gondii and cytomegalovirus was significant. Foetal outcome could be noted in some of the BOH patients. Toxoplasmosis was associated with complete abortion (38%), stillbirths (6%), premature delivery (16%) and congenital anomalies (6%). Cytomegalovirus infection was associated with complete abortion (41.66%), preterm delivery (33.33%) and congenital anomalies (8.33%). Ureaplasma infection in BOH patients resulted in preterm delivery with premature rupture of membranes in 45 per cent of women and complete abortion in 35 per cent.