Rapid induction of vitamin A deficiency in rabbits

Clinical and biochemical evidence of vitamin A deficiency was produced in rabbits as early as 4-5 weeks after weaning to a vitamin A deficient diet from dams maintained during lactation on the deficient diet. Mean serum retinol levels at the time of weaning for the deficient dams were 25 +/- 6 micrograms/dl compared with 74 +/- 8 micrograms/dl for the controls. Five weeks after weaning, 25% of pups fed the vitamin A deficient diet had ocular lesions characterized by the accumulation of sloughed epithelium on the cornea. At this time, mean serum values of the pups were 10 +/- 4 micrograms/dl for the deficient group and 73 +/- 8 micrograms/dl for the controls. Evidence of critically depleted liver stores was documented in the deficient rabbits by an elevated relative dose response test (54 +/- 18%) that did not occur in the control group (6 +/- 5%). Although food consumption was similar, weight gain was lower in the deficient group when compared to the control group.     

The physical properties of a fibrillar fibronectin-fibrinogen material with potential use in tissue engineering

Previous work has shown that orientated fibrous fibronectin-based materials can be useful in tissue repair and tissue engineering. The aim here was to characterise the basic material properties of a comparable orientated fibronectin-rich aggregate which is amenable to large scale production. Fine protein cables, diameter 150–200?μm, consisting of both fibronectin and fibrinogen in an approximately 2:1 molar ratio may be drawn from a cryoprecipitate-derived protein solution. The composition of the cables was found to depend on the ratio of the two proteins in the starting solution. The cable formation was associated with a reduction in the pH of the solution to between 4.0 and 4.5. Scanning electron microscopy of the cables showed that each one was composed of micron-diameter fibrils giving the material ultrastructural orientation. The cables possess moderate tensile strength (61?N/mm²) and displayed hygroscopic properties. Due to their natural composition, strict fibre alignment and the cell adhesive properties of fibronectin these cables form an effective template to orientate cells during tissue repair. Their properties and method of formation show promise for the scale-up of production.     

Characterization of fusion genes and the significantly expressed fusion isoforms in breast cancer by hybrid sequencing

We developed an innovative hybrid sequencing approach, IDP-fusion, to detect fusion genes, determine fusion sites and identify and quantify fusion isoforms. IDP-fusion is the first method to study gene fusion events by integrating Third Generation Sequencing long reads and Second Generation Sequencing short reads. We applied IDP-fusion to PacBio data and Illumina data from the MCF-7 breast cancer cells. Compared with the existing tools, IDP-fusion detects fusion genes at higher precision and a very low false positive rate. The results show that IDP-fusion will be useful for unraveling the complexity of multiple fusion splices and fusion isoforms within tumorigenesis-relevant fusion genes.     

A case of dextrocardia with normal situs.

We report here a case of dextrocardia with normal situs in an 81-year-old man who died from non-pulmonary causes. Removal of the chest wall revealed a large, but otherwise anatomically normal, left lung occupying the entire left hemithorax and extending across the midline to overlap the left border of the heart which was positioned in the right hemithorax. The gross anatomy of the heart was normal save its position and the presence of only 2 pulmonary veins. Dissection of the heart showed all chambers in their classically described position, and there were no valvular defects. The anatomy of the great vessels was also normal. The right lung was hypoplastic and lay posterior to the heart. This lung lacked any lobular structure, but the presence of carbon particles throughout it suggested that it was capable of normal inflation.     

Underwater microscopic sampling of a sublittoral kelp community

An encased incident-light microscope was constructed for use underwater to determine the relative abundances of micro-organisms living on natural sublittoral substrata in an Ecklonia radiata (C. Agardh) J. Agardh forest. By comparisons of data gathered using the microscope with data obtained from microscopic sampling of chips of natural substratum in the laboratory, the practicality and accuracy of the underwater microscope could be assessed. The repeatability of microscopic sampling in the field was determined by sampling certain areas of natural forest twice on the same day.A pilot survey of natural substrata in the kelp forest was done to determine patterns of spatial variability in the distribution of organisms sampled with the microscope. Analyses of variance and cost-benefit analyses of these data allowed calculation of optimal patch sizes and numbers of replicates to be used in future experiments. The importance of testing field methodologies and pilot studies was noted.     

Energy requirements of captive cotton-top tamarins (Saguinus oedipus oedipus)

Food intake of captive cotton-top tamarins was measured at various stages of the life cycle and energy intake was calculated from the results. The intake of adults for maintenance was found to vary around 500 kJ X kg-3/4 X day-1 and to decrease with age. During the last 8 weeks of pregnancy, females increased in weight by about 2 g X day-1 but energy intake did not show a marked rise above the maintenance range. During lactation, their energy intake appeared to double. Measurements of intake at various stages of growth were compared with a model of the energy requirements for growth which predicted intake quite closely. Compared with non-primate mammals of similar size, the growth rate of this species is slow, and because of this, the energy intake during growth and lactation is also comparatively low.     

The effect of various aquatic bacteria on the growth and senescence of duckweed (Lemna minor)

Five different species of freshwater bacteria ( Pseudomonas sp., Vibrio sp., Klebsiella sp., Enterobacter sp., Serratia sp.) and a mixed natural population were used separately to inoculate cultures of axenic duckweed ( Lemna minor ). Inoculation with Vibrio sp. caused the final population density of Lemna plants to be significantly greater after 52 d than that of either axenic controls or Lemna inoculated with a mixed bacterial community. Inoculation with Pseudomonas sp. caused the final population density of Lemna to be significantly higher than with the mixed bacterial treatment. Inoculation of Lemna with Klebsiella sp., Enterobacter sp. or Serratia sp. resulted in higher plant populations compared with controls, but these differences were not statistically significant. The presence of a mixed community of bacteria did not significantly affect the final population density of Lemna compared with the controls. However, Lemna plants inoculated with a natural population of bacteria showed significantly higher levels of senescence compared with the other five treatments and the controls. None of the five single bacterial taxa used appeared to have any significant effect of the sensescence of duckweed.