Globalized food systems are a major driver of climate change, biodiversity loss, environmental degradation, and the increasing prevalence of overweight and obesity in society. Small Island Developing States (SIDS) are particularly sensitive to the negative effects of rapid environmental change, with many also exhibiting a heavy reliance on food imports and high burdens of nutrition-related disease, resulting in calls to (re)localize their food systems. Such a transition represents a complex challenge, with adaptation interventions in one part of the food system contingent on the success of interventions in other parts.
View Article and Find Full Text PDFThe structural integrity of meningococcal native, micro-fluidized and activated capsular polysaccharides and their glycoconjugates - in the form most relevant to their potential use as vaccines (dilute solution) - have been investigated with respect to their homogeneity, conformation and flexibility. Sedimentation velocity analysis showed that the polysaccharide size distributions were generally bimodal with some evidence for higher molar mass forms at higher concentration. Weight average molar masses M where lower for activated polysaccharides.
View Article and Find Full Text PDFThree important physical properties which may affect the performance of glycoconjugate vaccines against serious disease are molar mass (molecular weight), heterogeneity (polydispersity), and conformational flexibility in solution. The dilute solution behaviour of native and activated capsular polyribosylribitol (PRP) polysaccharides extracted from Haemophilus influenzae type b (Hib), and the corresponding glycoconjugate made by conjugating this with the tetanus toxoid (TT) protein have been characterized and compared using a combination of sedimentation equilibrium and sedimentation velocity in the analytical ultracentrifuge with viscometry. The weight average molar mass of the activated material was considerably reduced (Mw ~ 0.
View Article and Find Full Text PDFTetanus toxoid protein has been characterized with regard oligomeric state and hydrodynamic (low-resolution) shape, important parameters with regard its use in glycoconjugate vaccines. From sedimentation velocity and sedimentation equilibrium analysis in the analytical ultracentrifuge tetanus toxoid protein is shown to be mostly monomeric in solution (~86%) with approximately 14% dimer. The relative proportions do not appear to change significantly with concentration, suggesting the two components are not in reversible equilibrium.
View Article and Find Full Text PDFCapsular polysaccharides from ten different serotypes of Streptococcus pneumoniae have been studied with regards their hydrodynamic properties in solution, namely their sedimentation coefficient and molar mass distributions, solution conformations and flexibilities (persistence lengths Lp), important properties for the construction of polysaccharide and glycoconjugate vaccines. Sedimentation and molar mass distributions (obtained by sedimentation velocity and equilibrium analysis in the analytical ultracentrifuge supported by size exclusion chromatography coupled to multi-angle light scattering measurements) were generally unimodal, with weight (mass) average molar masses ranging from 100×10(3) to 1300×10(3) g/mol. Estimates of chain flexibilities from three different procedures applied to intrinsic viscosity, sedimentation coefficient and molar mass data, showed that the polysaccharides from all the serotypes studied had semi-flexible structures in solution with persistence lengths in the range from ∼4 to 9 nm.
View Article and Find Full Text PDFArzneimittelforschung
June 1989
Desogestrel (150 micrograms), a potent progestogen virtually devoid of androgenic activity, was used in combination with 30 micrograms ethinyl estradiol as an oral contraceptive preparation (Marvelon). 219 women completed a total of 4074 cycles, and the use-effectiveness was 0.58 Pearl Units.
View Article and Find Full Text PDFClinical signs of virilization in patients with granulosa cell tumours are reported in approx. 2% of the cases, but hormonal investigation has been rarely performed. We present the clinical, histological and hormonal data obtained in a premenopausal, amenorrhoeic woman, with a testosterone-producing granulosa cell tumour.
View Article and Find Full Text PDFThe relationship between the presence or absence of an ovulation stigma and (1) the fertility status, (2) the incidence of endometriosis, (3) the concentration of progesterone and estradiol in the peritoneal fluid, and (4) the blood levels of luteinizing hormone, follicle-stimulating hormone, progesterone, and estradiol in 21 fertile and 45 infertile patients who underwent a laparoscopy in the early (n = 48) or late luteal phase (n = 18) was investigated. An ovulation stigma was observed in about half of the patients, irrespective of their fertility status (past and subsequent), the presence of endometriosis, or the time of the luteal phase. Progesterone and estradiol concentrations in the peritoneal fluid were highest in the early luteal phase, but they were not correlated with the presence or absence of an ovulation stigma.
View Article and Find Full Text PDF