Ultrastructural Studies On Stomata Development In Internodes Of Avena Sativa

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/141606/1/ajb209789.pd

Intracisternal fibers in the liver cells of starved frogs

Fibers observed within the cisternae of endoplasmic reticulum of liver cells of Rana pipiens are described. Fibers were observed only in animals subjected to starvation, but the frequency of fiber occurrence was found to vary widely from animal to animal and from cell to cell within the same animal. It is, therefore, suggested that starvation is important in, but not solely responsible for, the process of fiber formation. Some characteristic morphological changes observed in fiber-containing cells are described, and a tentative theory outlining a possible sequence of steps involved in fiber formation is presented.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/33871/1/0000132.pd

Quantitative ultrastructural studies of hepatocytes from fed and starved frogs

Stereological analysis of liver tissue excised from mature female Rana pipiens starved for 59 days and from a fed control group was conducted both at the light and electron microscopy levels. Average cellular volume decreased by more than a factor of 4 following prolonged fasting. Nuclear volume was not significantly decreased. Mitochondrial volume per cell showed a slight, though not statistically significant, decrease from 540 Μm 3 to 420 Μm 3 . Rough endoplasmic reticulum decreased in absolute surface area per cell from 13,600 Μm 2 /cell to 3,000 Μm 2 /cell after starvation, but its surface density in the cytoplasm remained relatively constant. Lipid decreased from 650 Μm 3 per cell to less than 1 Μm 3 per cell after fasting. Glycogen decreased from 49% of hepatocyte cytoplasmic volume to less than 15%, a decrease in absolute volume from 4,000–240 Μm 3 per cell. Glycogen changed from the Α to the Β-configuration during fasting. Condensed cross-banded fibers or sheets formed within the rough endoplasmic reticulum cisternae of some fasted animals. The significance of these results relative to the energy metabolism of poikilotherms is discussed.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/38085/1/1402100304_ftp.pd

Argon laser micro-irradiation of mitochondria in rat myocardial cells in tissue culture. IV. Ultrastructural and cytochemical analysis of minimal lesions.

Laser irradiated mitochondria in rat myocardial cells were analysed cytochemically for succinic dehydrogenase and with the electron microscope for ultrastructure. The least severe lesion type did not alter the SDH activity of the mitochondria. The major ultrastructural alteration observed was an electron-dense region corresponding to a phase-dark spot in the light micrographs. This lesion appeared to be restricted in depth and width within the irradiated structure. The damage was primarily localized to the intercristae matrix. The cristae appeared normal. © 1973

Randomised controlled trial of four commercial weight loss programmes in the UK: initial findings from the BBC “diet trials”

Objective To compare the effectiveness of four commercial weight loss diets available to adults in the United Kingdom. Design Six month multicentre randomised unblinded controlled trial. Setting Community based sample of otherwise healthy overweight and obese adults. Interventions Dr Atkins' new diet revolution, Slim-Fast plan, Weight Watchers pure points programme, and Rosemary Conley's eat yourself slim diet and fitness plan. Main outcome measures Weight and body fat changes over six months. Results All diets resulted in significant loss of body fat and weight over six months. Groups did not differ significantly but loss of body fat and weight was greater in all groups compared with the control group. In an intention to treat analysis, average weight loss was 5.9 kg and average fat loss was 4.4 kg over six months. The Atkins diet resulted in significantly higher weight loss during the first four weeks, but by the end was no more or less effective than the other diets. Conclusions Clinically useful weight loss and fat loss can be achieved in adults who are motivated to follow commercial diets for a substantial period. Given the limited resources for weight management in the NHS, healthcare practitioners should discuss with their patients programmes known to be effective. Trial registration Clinical trials NCT00327821