Sucrose uptake and compartmentation in sugar beet taproot tissue.

Active sucrose uptake by discs of mature sugar beet (Beta vulgaris L. cv GW-D2 and USH-20) root tissue shows a biphasic dependence on external sucrose. At concentrations up to 20 millimolar sucrose, the active uptake mechanism appears to approach saturation, with an apparent K(m) of 3.

Hemodynamics, regional myocardial blood flow, and sarcoplasmic reticulum calcium uptake in right ventricular hypertrophy and failure.

Either right ventricular hypertrophy (RVH) or failure (RVF) was produced by pulmonary arterial banding in 47 piglets aged 3-6 weeks. When sufficient time was allowed to elapse after banding, RVH was present in 30 and had progressed to RVF in 17. These two groups were compared with 24 control, i.

Biosynthesis, translocation, and accumulation of betaine in sugar beet and its progenitors in relation to salinity.

Like other halophytic chenopods, sugar beet (Beta vulgaris L.) can accumulate high betaine levels in shoots and roots. N,N,N-trimethylglycine impedes sucrose crystallization and so lowers beet quality.

Clinical diagnosis by transcutaneous Doppler ultrasound.

Transcutaneous Doppler ultrasound represents a convenient, reliable technique for the non-invasive diagnosis and assessment of a rapidly increasing number of diverse circulatory disorders.

Reduction in Sink-Mobilizing Ability following Periods of High Carbon Flux.

Sink tissues may play a significant role in determining photosynthetic rates through their ability to mobilize assimilates. The objective in this study was to determine if the mobilizing ability of taproot sink tissues of sugarbeet (Beta vulgaris) could become limiting when assimilate supply was maintained at a high level for an extended period of time. Assimilate supply was either enhanced by CO(2) enrichment or reduced by shading.

Characterization of the lateral interface between normal and ischemic tissue in the canine heart during evolving myocardial infarction.

A new nonrotating multiple biopsy device has been developed to allow the rapid, simultaneous and contiguous sampling of cardiac muscle in the large mammalian heart. Each cutter obtains 40 adjacent transmural left ventricular biopsy samples, each of 4 mm section. The epicardial 1.

Sarcomere relaxation and ischaemic myocardial injury.

Material from hearts known to have had recent myocardial infarction and biopsies of dog hearts subjected to an experimental procedure producing ischaemic injury, were examined by polarising microscopy. A technique which depends on the relaxation of sarcomeres on ischaemic areas of myocardia was used and assessed for its value in the diagnosis of early myocardial infarction. We found no statistically significant difference in sarcomere lengths in ischaemic and control heart muscle in man.

Differential atrial filling after Mustard and Senning repairs. Detection by transcutaneous Doppler ultrasound.

The dominance of Mustard's operation for transposition of the great arteries has been challenged by the recent revival of Senning's repair because it promises better long-term results in terms of venous obstruction and atrial haemodynamics. These hypotheses were tested by recording jugular venous flow waveforms transcutaneously in 24 postoperative patients with simple complete transposition using a bidirectional Doppler blood velocimeter. Eight patients had undergone Mustard's operation and 16 the Senning alternative; all had previously had a postoperative cardiac catheterisation.

Alkali Cation/Sucrose Co-transport in the Root Sink of Sugar Beet.

The mechanism of sucrose transport into the vacuole of root parenchyma cells of sugar beet was investigated using discs of intact tissue. Active sucrose uptake was evident only at the tonoplast. Sucrose caused a transient 8.

Sucrose uptake by sugar beet tap root tissue.

Sucrose uptake by discs of mature sugar beet root tissue incubated in [(14)C]-sucrose exhibited nonsaturating kinetics over the concentration range of 1 to 500 millimolar. Uptake was inhibited by dinitrophenol, sodium cyanide, low O(2), and penetrating sulfhydryl inhibitors. ATPase inhibitors, sodium fluoride, and oligomycin reduced uptake by 20 and 40%, respectively.

Gas-liquid chromatographic measurement of lignocaine in small samples of canine myocardium after enzymatic digestion.

A method is described whereby lignocaine can be measured in small samples of canine myocardium. A proteolytic enzyme is used to digest the tissue, and the drug, together with an internal standard, is subsequently extracted into an organic solvent and measured by gas-liquid chromatography. The method is reproducible using tissue samples as small as 50 mg and appears to be suitable for the measurement of a number of drugs in small samples of tissue.

Experimental right ventricular hypertrophy and failure in swine.

Following pulmonary arterial constriction, 22 pigs developed right ventricular failure and 10 right ventricular hypertrophy. Comparing results with those obtained in 21 normal pigs (no pulmonary artery constriction), it was found the right ventricular peak systolic and end-diastolic pressures, cardiac output, and right ventricular weight distinguished hypertrophied and failing hearts from normal ones. Cardiac output was lower in failing hearts than in hypertrophied hearts and was the only variable which significantly differentiated between these two groups.

Enzymes Involved in the Postharvest Degradation of Sucrose in Beta vulgaris L. Root Tissue.

The reducing sugar content of sugar beet (Beta vulgaris L.) roots increased during 30 days of storage at 21 C and 160 days at 5 C as a result of an increase in acid invertase activity. Sucrose synthetase and neutral invertase activities were high at harvest but declined during storage, thus showing no relationship with postharvest reducing sugar accumulation in sugar beet roots.