Acute and chronic effects of multivitamin/mineral supplementation on objective and subjective energy measures

Background

Vitamins and minerals play an essential role within many cellular processes including energy production and metabolism. Previously, supplementation with a multivitamin/mineral (MVM) for ≥28 days resulted in improvements to cognition and subjective state. We have also demonstrated shifts in metabolism during cognitively demanding tasks following MVM in females, both acutely and following 8-week supplementation. The current study aimed to assess these effects further in males and females using metabolically challenging exercise and cognitive tasks.

Methods

The current randomised, placebo-controlled, parallel groups study investigated the effects of a MVM complex in 82 healthy young (18-35y) exercisers. Subjective ratings and substrate metabolism were assessed during 30 min each of increasingly effortful incremental exercise and demanding cognitive tasks. Assessments took place on acute study days following a single dose (Day 1) of MVM, containing 3 times recommended daily allowance of water-soluble vitamins plus CoQ10, and following 4-week supplementation (Day 28).

Results

Energy expenditure (EE) was increased during cognitive tasks following MVM across Day 1 and Day 28, with greater effects in males. In males, MVM also increased carbohydrate oxidation and energy expenditure during exercise across Day 1 and Day 28. In females, mental tiredness was lower during exercise; increases in physical tiredness following 30 min of exercise were attenuated; and stress ratings following cognitive tasks were reduced following MVM. In males, MVM only lowered mental tiredness following 10 min of exercise. These effects were apparent irrespective of day, but effects on mental tiredness were greater on Day 28. Ferritin levels were also higher on Day 28 in those receiving MVM.

Conclusion

These findings extend on existing knowledge, demonstrating increased carbohydrate oxidation and increased energy expenditure in males following MVM supplementation for the first time. Importantly, they show modulation of energy expenditure and subjective tiredness following a single dose, providing further evidence for acute effects of MVM. Differential effects in men and women suggest that sex may play an important role in the effects of MVM on energy metabolism and should be considered in future research.

Trial registration

ClinicalTrials.gov, NCT03003442. Registered 22nd November 2016 – retrospectively registered

Sugarcane for water-limited environments. Variation in stomatal conductance and its genetic correlation with crop productivity

Stomatal conductance (g(s)) and canopy temperature have been used to estimate plant water status in many crops. The behaviour of g(s) in sugarcane indicates that the internal leaf water status is controlled by regular opening and closing of stomata. A large number of g(s) measurements obtained across varying moisture regimes, locations, and crop cycles with a diverse sugarcane germplasm composed of introgression, and commercial clones indicated that there is a high genetic variation for g(s) that can be exploited in a breeding programme. Regardless of the environmental influences on the expression of this trait, moderate heritability was observed across 51 sets of individual measurements made on replicated trials over 3 years. The clone×water status interaction (G×E) variation was smaller than the clone (G) variation on many occasions. A wide range of genetic correlations (r(g)= -0.29 to 0.94) between g(s) and yield were observed across test environments in all three different production regions used. Canopy conductance (g(c)) based on g(s) and leaf area index (LAI) showed a stronger genetic correlation than the g(s) with cane yield (tonnes of cane per hectare; TCH) at 12 months (mature crop). The regression analysis of input weather data for the duration of measurements showed that the predicted values of r(g) correlated with the maximum temperature (r=0.47) during the measurements and less with other environmental variables. These results confirm that the g(c) could have potential as a criterion for early-stage selection of clones in sugarcane breeding programmes.

Sugarcane for water-limited environments. Genetic variation in cane yield and sugar content in response to water stress

Water limitation is a major production constraint for sugarcane worldwide. However, to date, there has been little investigation of patterns of genetic variation in the response to water stress in sugarcane. Field experiments were conducted over 3 years under fully irrigated and managed water stress conditions at two locations in Northern Queensland in Australia. Eighty-nine genetically diverse clones were evaluated for their yield performance and sugar attributes. Water stress treatments reduced cane yield [tonnes of cane per hectare (TCH)] and total dry matter (TDM) by 17-52% and 20-56%, respectively, compared with irrigated treatments in the same experiments. Nevertheless, there was little genotype×environment interaction variation for TCH, TDM, or commercial cane sugar (CCS), and hence high genetic correlations between the irrigated and water stress treatments across environments. Both commercial and unselected clones performed poorly under severe stress environments, while the commercial clones outperformed the unselected clones under mild and moderate stress conditions. The results presented here highlight the contribution of intrinsic potential yields (yield under well-irrigated conditions) of some selected and unselected clones to maintain relatively high productivity in a range of moderate stress conditions imposed. The physiological basis for the high genetic correlations is at present unclear, but some explanations are hypothesized. The choice of stress levels in selection trials would not appear to be a critical issue for sugarcane breeding programmes, at least for the early phases of selection, where similar ranking clones across a range of moderate water stresses may be expected.

Multicentre evaluation of intraoperative molecular analysis of sentinel lymph nodes in breast carcinoma

Background

Ideally, intraoperative sentinel lymph node (SLN) analysis in breast cancer should be automated, have high concordance with extensive histopathology, and be applicable in any hospital setting. A prospective multicentre evaluation of the one-step nucleic acid amplification (OSNA) automated molecular diagnostic system of SLN analysis was undertaken.

Methods

Intraoperative examination of SLNs from 204 patients with breast cancer was performed by OSNA at four sites in the UK. Half of each SLN was assessed by OSNA (for cytokeratin 19 mRNA) and the remaining half was paraffin embedded for intensive histological examination at ten levels. Discordant cases were reanalysed by further molecular biological techniques and by additional histological examination of all remaining nodal material to ascertain whether the discordance was due to an uneven distribution of metastases, known as tissue allocation bias (TAB).

Results

After exclusion of samples affected by TAB, the overall concordance rate for OSNA versus histopathology was 96·0 per cent, with a sensitivity of 91·7 per cent and a specificity of 96·9 per cent. The median time to process a single SLN was 32 (range 22–97) min, and that for two nodes 42 (30–73) min.

Conclusion

OSNA enables accurate automated intraoperative diagnosis and can be used successfully in different UK hospitals. When the SLN is shown to be positive, the patient can undergo immediate axillary clearance under the same anaesthetic rather than having a delayed second procedure.

Genetic control of yield related stalk traits in sugarcane

A major focus of sugarcane variety improvement programs is to increase sugar yield, which can be accomplished by either increasing the sugar content of the cane or by increasing cane yield, as the correlation between these traits is low. We used a cross between an Australian sugarcane variety Q165, and a Saccharum officinarum accession, IJ76-514, to dissect the inheritance of yield-related traits in the complex polyploid sugarcane. A population of 227 individuals was grown in a replicated field trial and evaluated over 3 years for stalk weight, stalk diameter, stalk number, stalk length and total biomass. Over 1,000 AFLP and SSR markers were scored across the population and used to identify quantitative trait loci (QTL). In total, 27 regions were found that were significant at the 5% threshold using permutation tests with at least one trait; individually, they explained from 4 to 10% of the phenotypic variation and up to 46% were consistent across years. With the inclusion of digeneic interactions, from 28 to 60% of the variation was explained for these traits. The 27 genomic regions were located on 22 linkage groups (LGs) in six of the eight homology groups (HGs) indicating that a number of alleles or quantitative trait alleles (QTA) at each QTL contribute to the trait; from one to three alleles had an effect on the traits for each QTL identified. Alleles of a candidate gene, TEOSINTE BRANCHED 1 (TB1), the major gene controlling branching in maize, were mapped in this population using either an SSR or SNP markers. Two alleles showed some association with stalk number, but unlike maize, TB1 is not a major gene controlling branching in sugarcane but only has a minor and variable effect.

Construction of a genetic linkage map for Saccharum officinarum incorporating both simplex and duplex markers to increase genome coverage

Saccharum officinarum L. is an octoploid with 80 chromosomes and a basic chromosome number of x = 10. It has high stem sucrose and contributes 80% of the chromosomes to the interspecific sugarcane cultivars that are grown commercially for sucrose. A genetic linkage map was developed for S. officinarum (clone IJ76-514) using a segregating population generated from a cross between Q165 (a commercial sugarcane cultivar) and IJ76-514. In total, 40 AFLP and 72 SSR primer pairs were screened across the population, revealing 595 polymorphic bands inherited from IJ76-514. These 595 markers displayed a frequency distribution different from all other sugarcane genetic maps produced, with only 40% being simplex markers (segregated 1:1). Of these 240 simplex markers, 178 were distributed on 47 linkage groups (LGs) and 62 remained unlinked. With the addition of 234 duplex markers and 80 biparental simplex markers (segregating 3:1), 534 markers formed 123 LGs. Using the multi-allelic SSR markers, repulsion phase linkage, and alignment with the Q165 linkage map, 105 of the 123 LGs could be grouped into 10 homology groups (HGs). These 10 HGs were further assigned to the 8 HGs observed in cultivated sugarcane and S. spontaneum. Analysis of repulsion phase linkage indicated that IJ76-514 is neither a complete autopolyploid nor an allopolyploid. Detection of 28 repulsion linkages that occurred between 6 pairs of LGs located in 4 HGs suggested the occurrence of limited preferential chromosome pairing in this species.

Evaluation of the dissemination and implementation of a nutritional guideline for pressure ulcer care

OBJECTIVE

In 2004 the European Pressure Ulcer Advisory Panel nutritional working group developed a nutritional guideline for pressure ulcer prevention and treatment. This study investigated the degree to which the guideline was disseminated and implemented in clinical practice.

METHOD

A cross-sectional study was undertaken in health-care organisations in The Netherlands, Germany and the UK. A printed, standardised questionnaire which followed Rogers' model of the innovation-decision process was developed, translated and distributed to 1087 health-care organisations.

RESULTS

The response rate was 33% (n = 363). Sixty-one per cent of respondents knew of the guideline. Twenty-five per cent had applied it to their clinical practice and used it for nutritional screening. The main barrier to the provision of nutritional support appeared to be lack of knowledge and skills.

CONCLUSION

One year after its dissemination, more than half of respondents knew of the guideline, with one in four applying it to their practice. The guideline was better disseminated and implemented in The Netherlands and UK than in Germany, where only 4% of participants had used it.

Quantitative trait loci identified for sugar related traits in a sugarcane (Saccharum spp.) cultivar x Saccharum officinarum population

The identification of markers linked to quantitative trait loci (QTLs) for increased sugar accumulation could improve the effectiveness of current breeding strategies in sugarcane. Progeny from a cross between a high sucrose producing cultivar, (denotes Australian plant breeding rights), and a Saccharum officinarum clone, IJ76-514 were grown in two field experiments in different years, and evaluated in the early and mid-season phases of crop maturity, to identify robust QTLs in affecting sucrose content in cane. Using an extensive genetic map constructed for with over 1,000 AFLP and SSR markers, a total of 37 QTLs were identified for brix and pol of which, 16 were detected in both experiments. Of these 37 QTL, 30 were clustered into 12 genomic regions in six of the eight homo(eo)logous groups. Each QTL explained from 3 to 9% of the phenotypic variation observed. Both positive and negative effects were identified and the location of the QTLs on linkage groups belonging to the same homo(eo)logy group suggested that a number of the QTLs were allelic forms of the same genes. Of the 37 QTLs identified, the majority were significant in both early and mature cane, but 8 were identified as early specific QTLs and 9 as mature cane QTLs. In total, 97 interactions were significant (P<10(-5)) and these were localised to 32 genomic regions of which 6 were detected with both years' data. Models including all the QTLs explained from 37 to 66% of the total phenotypic variation, depending on the trait. The results will be subsequently applied in marker assisted breeding.

The contribution of extensin network formation to rapid, hydrogen peroxide-mediated increases in grapevine callus wall resistance to fungal lytic enzymes

Grapevine (Vitis vinifera cv. Touriga) callus cell walls contain a high level of the monomeric extensin, GvP1. Hydrogen peroxide stimulus of these cultures causes the rapid loss of monomeric GvP1, concomitant with marked increases in insoluble GvP1 amino acids and wall resistance to digestion by fungal lytic enzymes. JIM11 immunolocalization studies indicated that monomeric and network GvP1 were evenly distributed in the callus cell wall. These primary cell walls were used to investigate the specific contribution of extensin and other ionically bound cell-wall proteins to hydrogen peroxide-mediated increases in resistance to fungal lytic enzymes. This was performed by removing ionically-bound proteins and assaying for hydrogen peroxide-enhanced resistance after the addition of selected protein fractions. The results indicate that hydrogen peroxide-induced increases in resistance to digestion by fungal lytic enzymes require a co-operative action between network extensin formation and the electrostatic interaction of additional wall proteins with the extracellular matrix.

A combination of AFLP and SSR markers provides extensive map coverage and identification of homo(eo)logous linkage groups in a sugarcane cultivar

Sugarcane varieties are complex polyploids carrying in excess of 100 chromosomes and are derived from interspecific hybridisation between the domesticated Saccharum officinarum and the wild relative S. spontaneum. A map was constructed in Denotes variety covered by Australian plant breeding rights., an Australian cultivar, from a segregating F1 population, using 40 amplified fragment length polymorphism (AFLP) primer combinations, five randomly amplified DNA fingerprints (RAF) primers and 72 simple sequence repeat (SSR) primers. Using these PCR-based marker systems, we generated 1,365 polymorphic markers, of which 967 (71%) were single-dose (SD) markers. Of these SD 967 markers, 910 were distributed on 116 linkage groups (LGs) with a total map length of 9,058.3 cM. Genome organisation was significantly greater than observed in previously reported maps for Saccharum spp. With the addition of 123 double-dose markers, 36 (3:1) segregating markers and a further five SD markers, 1,074 markers were mapped onto 136 LGs. Repulsion phase linkage detected preferential pairing for 40 LGs, which formed 11 LG pairs and three multi-chromosome pairing groups. Using SSRs, double-dose markers and repulsion phase linkage, we succeeded in forming 127 of the 136 LGs into eight homo(eo)logy groups (HG). Two HGs were each represented by two sets of LGs. These sets of LGs potentially correspond to S. officinarum chromosomes, with each set aligning to either end of one or two larger LGs. The larger chromosomes in the two HGs potentially correspond to S. spontaneum chromosomes. This suggestion is consistent with the different basic chromosome number of the two species that are hybridised to form sugarcane cultivars, S. spontaneum (x=8) and S. officinarum (x=10), and illustrates the structural relationship between the genomes of these two species. The discrepancy of coverage between HGs highlights the difficulty in mapping large parts of the genome.

Effects of tissue culture, biolistic transformation, and introduction of PPO and SPS gene constructs on performance of sugarcane clones in the field

Stably transformed sugarcane plants were produced by the biolistic introduction of DNA into tissue-cultured cells. Constructs containing genes in sense and antisense orientation of polyphenol oxidase and sense orientation of sucrose phosphate synthase were used in the transformations. Regenerated plants were grown in a series of field experiments that incorporated commercial varieties, including Q117, from which the transgenic clones were derived and plants regenerated from tissue culture but not subjected to biolistic bombardment. In all experiments, the mean yield of transgenic sugarcane was lower than commercial varieties and the transgenic clones often exhibited lower sugar content, although individual transgenic clones in some experiments were not significantly different from Q117. Those plants regenerated from tissue culture but not bombarded were intermediate in their yield, and more clones were equivalent to Q117 in agronomic performance. Transformed plants produced by the bombardment of callus performed poorly but the results from the tissue-cultured controls indicated that not all of this could be due to somaclonal variation. Some aspect(s) of the process of transformation itself was deleterious and in most cases more significant than the effects due to tissue culture. Of the transgenic clones grown at Ayr, Queensland, 1.6% were equivalent to Q117 in sugar content and yield, suggesting that large numbers of transgenic clones would have to be generated using the current method in order to allow for selection of clones with acceptable agronomic performance.

Lodging reduces sucrose accumulation of sugarcane in the wet and dry tropics

Previous experiments in the Australian tropics have observed a 'slowdown' in biomass accumulation in mature sugarcane crops. By installing scaffolding to prevent lodging, we eliminated the growth 'slowdown' in 3 experiments to confirm that lodging and stalk death are part of the explanation. In both the wet and dry (irrigated) tropics, lodging of sugarcane significantly decreased both fresh cane yield and commercial cane sugar content (CCS). Prevention of lodging increased cane yield by 11–15%, CCS by 3–12%, and sugar yield by 15–35% at the final harvest in August–September. The rate of increase in CCS in lodged cane was reduced following lodging, although CCS had partially recovered by harvest.A possible component of the lodging effect is a slowdown in the growth due to the ageing of the crop. However, a younger crop (late crop treatment) grew no faster than the scaffolded treatment and so discounted this. In the dry tropics, where cane is irrigated and grows under high radiation, sugar yield was 40 t/ha with scaffolding installed. The increased yield (compared with 35 t/ha in lodged cane) was due to both the survival of an extra 0.8 stalks/m2 and increased accumulation of sugar in live stalks. In 2 years in the wet tropics where sugar yield with scaffolding was 16 t/ha, the same factors, with the addition of increased biomass accumulation in live stalks, were responsible for the increase.

Rapid deposition of extensin during the elicitation of grapevine callus cultures is specifically catalyzed by a 40-kilodalton peroxidase

Elicitation or peroxide stimulation of grape (Vitis vinifera L. cv Touriga) vine callus cultures results in the rapid and selective in situ insolubilization of an abundant and ionically bound cell wall protein-denominated GvP1. Surface-enhanced laser desorption/ionization/time of flight-mass spectrometry analysis, the amino acid composition, and the N-terminal sequence of purified GvP1 identified it as an 89.9-kD extensin. Analysis of cell walls following the in situ insolubilization of GvP1 indicates large and specific increases in the major amino acids of GvP1 as compared with the amino acids present in salt-eluted cell walls. We calculate that following deposition, covalently bound GvP1 contributes up to 4% to 5% of the cell wall dry weight. The deposition of GvP1 in situ requires peroxide and endogenous peroxidase activity. Isoelectric focusing of saline eluates of callus revealed only a few basic peroxidases that were all isolated or purified to electrophoretic homogeneity. In vitro and in situ assays of extensin cross-linking activity using GvP1 and peroxidases showed that a 40-kD peroxidase cross-linked GvP1 within minutes, whereas other grapevine peroxidases had no significant activity with GvP1. Internal peptide sequences indicated this extensin peroxidase (EP) is a member of the class III peroxidases. We conclude that we have identified and purified an EP from grapevine callus that is responsible for the catalysis of GvP1 deposition in situ during elicitation. Our results suggest that GvP1 and this EP play an important combined role in grapevine cell wall defense.

Effect of vagal cooling on the counterregulatory response to hypoglycemia induced by a low dose of insulin in the conscious dog

We previously demonstrated, using a nerve-cooling technique, that the vagus nerves are not essential for the counterregulatory response to hypoglycemia caused by high levels of insulin. Because high insulin levels per se augment the central nervous system response to hypoglycemia, the question arises whether afferent nerve fibers traveling along the vagus nerves would play a role in the defense of hypoglycemia in the presence of a more moderate insulin level. To address this issue, we studied two groups of conscious 18-h-fasted dogs with cooling coils previously placed on both vagus nerves. Each study consisted of a 100-min equilibration period, a 40-min basal period, and a 150-min hypoglycemic period. Glucose was lowered using a glycogen phosphorylase inhibitor and a low dose of insulin infused into the portal vein (0.7 mU.kg(-1) min(-1)). The arterial plasma insulin level increased to 15 +/- 2 microU/ml and the plasma glucose level fell to a plateau of 57 +/- 3 mg/dl in both groups. The vagal cooling coils were perfused with a 37 degrees C (SHAM COOL; n = 7) or a -20 degrees C (COOL; n = 7) ethanol solution for the last 90 min of the study to block parasympathetic afferent fibers. Vagal cooling caused a marked increase in the heart rate and blocked the hypoglycemia-induced increase in the arterial pancreatic polypeptide level. The average increments in glucagon (pg/ml), epinephrine (pg/ml), norepinephrine (pg/ml), cortisol (microg/dl), glucose production (mg.kg(-1). min(-1)), and glycerol (micromol/l) in the SHAM COOL group were 53 +/- 9, 625 +/- 186, 131 +/- 48, 4.63 +/- 1.05, -0.79 +/- 0.24, and 101 +/- 18, respectively, and in the COOL group, the increments were 39 +/- 7, 837 +/- 235, 93 +/- 39, 6.28 +/- 1.03 (P < 0.05), -0.80 +/- 0.20, and 73 +/- 29, respectively. Based on these data, we conclude that, even in the absence of high insulin concentrations, afferent signaling via the vagus nerves is not required for a normal counterregulatory response to hypoglycemia.

Effect of hepatic denervation on the counterregulatory response to insulin-induced hypoglycemia in the dog

Our aim was to determine whether complete hepatic denervation would affect the hormonal response to insulin-induced hypoglycemia in dogs. Two weeks before study, dogs underwent either hepatic denervation (DN) or sham denervation (CONT). In addition, all dogs had hollow steel coils placed around their vagus nerves. The CONT dogs were used for a single study in which their coils were perfused with 37 degrees C ethanol. The DN dogs were used for two studies in a random manner, one in which their coils were perfused with -20 degrees C ethanol (DN + COOL) and one in which they were perfused with 37 degrees C ethanol (DN). Insulin was infused to create hypoglycemia (51 +/- 3 mg/dl). In response to hypoglycemia in CONT, glucagon, cortisol, epinephrine, norepinephrine, pancreatic polypeptide, glycerol, and hepatic glucose production increased significantly. DN alone had no inhibitory effect on any hormonal or metabolic counterregulatory response to hypoglycemia. Likewise, DN in combination with vagal cooling also had no inhibitory effect on any counterregulatory response except to reduce the arterial plasma pancreatic polypeptide response. These data suggest that afferent signaling from the liver is not required for the normal counterregulatory response to insulin-induced hypoglycemia.

Pathologic features of uterine leiomyomas following uterine artery embolization

Bilateral uterine artery embolization has recently been employed as an alternative to operational treatment of uterine leiomyomas. The pathologic features induced by uterine artery embolization have not been previously described in detail. Usually patients experience symptomatic improvement with a reduction in size of the leiomyomas. This report describes the pathologic features in a series of 10 uterine leiomyomas where tissue was available for histologic examination following uterine artery embolization. Characteristic histologic features within the leiomyomas included massive necrosis, sometimes with dystrophic calcification, vascular thrombosis, and intravascular foreign material that elicited a histiocytic and foreign-body giant cell reaction. In some cases, intravascular foreign material was present elsewhere in the myometrium, the cervix, or paraovarian region. In occasional cases, there were foci of myometrial necrosis and microabscess formation beyond the confines of the leiomyomas. Foci of extrauterine inflammation were also occasionally identified. Histopathologists should be aware of these findings because the use of uterine artery embolization will possibly become more widespread in the future.

Portal glucose infusion increases hepatic glycogen deposition in conscious unrestrained rats

It has been demonstrated in the conscious dog that portal glucose infusion creates a signal that increases net hepatic glucose uptake and hepatic glycogen deposition. Experiments leading to an understanding of the mechanism by which this change occurs will be facilitated if this finding can be reproduced in the rat. Rats weighing 275-300 g were implanted with four indwelling catheters (one in the portal vein, one in the left carotid artery, and two in the right jugular vein) that were externalized between the scapulae. The rats were studied in a conscious, unrestrained condition 7 days after surgery, following a 24-h fast. Each experiment consisted of a 30- to 60-min equilibration, a 30-min baseline, and a 120-min test period. In the test period, a pancreatic clamp was performed by using somatostatin, insulin, and glucagon. Glucose was given simultaneously either through the jugular vein to clamp the arterial blood level at 220 mg/dl (Pe low group) or at 250 mg/dl (Pe high group), or via the hepatic portal vein (Po group; 6 mg. kg(-1). min(-1)) and the jugular vein to clamp the arterial blood glucose level to 220 mg/dl. In the test period, the arterial plasma glucagon and insulin levels were not significantly different in the three groups (36 +/- 2, 33 +/- 2, and 30 +/- 2 pg/ml and 1.34 +/- 0.08, 1. 37 +/- 0.18, and 1.66 +/- 0.11 ng/ml in Po, Pe low, and Pe high groups, respectively). The arterial blood glucose levels during the test period were 224 +/- 4 mg/dl for Po, 220 +/- 3 for Pe low, and 255 +/- 2 for Pe high group. The liver glycogen content (micromol glucose/g liver) in the two Pe groups was not statistically different (51 +/- 7 and 65 +/- 8, respectively), whereas the glycogen level in the Po group was significantly greater (93 +/- 9, P < 0.05). Because portal glucose delivery also augments hepatic glycogen deposition in the rat, as it does in the dogs, mechanistic studies relating to its function can now be undertaken in this species.

A comparison of thoracic and lumbar epidural techniques for post-thoracoabdominal esophagectomy analgesia

PURPOSE

To compare thoracic epidural analgesia (TEA) using a bupivacaine/fentanyl mixture and lumbar epidural analgesia (LEA) with morphine, in respect to the time to extubation and the quality of post-operative analgesia, in patients having thoracoabdominal esophagectomy.

METHODS

Twenty two patients scheduled for elective thoracoabdominal esophagectomy were randomized to TEA or LEA. Postoperatively, the TEA group received Patient Controlled Epidural Analgesia (PCEA) with bupivacaine 0.125% and 5 microg x ml(BI) fentanyl, and the LEA group received PCEA with 0.2 microg x ml(BI) morphine. A blinded observer assessed criteria for tracheal extubation and the time of tracheal extubation was recorded. Early extubation was defined as tracheal extubation within four hours postoperatively. Visual analogue pain scores at rest (Static Visual Analogue Pain Scores, SVAPS) and with movement (Dynamic Visual Analogue Pain Scores, DVAPS) were recorded at 1, 6, 12, 18 and 24 hr post-extubation. Failure of the epidural protocol (FEP) was defined as a request for additional analgesia.

RESULTS

Tracheal extubation was achieved in 70% of the LEA and 100% of the TEA at four hours postoperatively (P=NS). However, the TEA group achieved earlier extubation times when assessed with log rank testing (P = 0.01). By six hours post-extubation FEP had occurred in 50% of the LEA group but in none of the TEA group (P = 0.01). Mean SVAPS and DVAPS were lower in the TEA than in the LEA group at all measured times (P < 0.01).

CONCLUSION

This study has demonstrated superior pain control in patients undergoing thoraco-abdominal esophagectomy treated with TEA than with LEA, particularly for pain with movement. Tracheal extubation occurred earlier in the TEA group, but this difference was not significant at four hours postoperatively.

Memory for duration: role of hippocampus and medial prefrontal cortex

In this task rats had to learn that a three-dimensional object stimulus (a rectangle) that was visible for 2 s would result in a positive (go) reinforcement for one object (a ball) and no reinforcement (no go) for a different object (a bottle). However, if the rectangle stimulus was visible for 8 s then there would be no reinforcement for the ball (no go), but a reinforcement for the bottle (go). After rats learned this conditional discrimination by responding differentially in terms of latency to approach the object, they received large (dorsal and ventral) lesions of the hippocampus, lesions of the medial prefrontal cortex (anterior cingulate and precentral cortex), lesions of the cortex dorsal to the dorsal hippocampus, or served as sham-operated controls. Following recovery from surgery they were retested. The results indicate that there were major impairments following hippocampal lesions, in contrast to cortical control and medial prefrontal cortex lesions, as indicated by smaller latency differences between positive and negative trials on postsurgery tests. In order to ensure that the deficits observed with hippocampal lesions were not due to a discrimination problem, new rats were trained in an object (gray cylinder) duration discrimination task. In this go/no go procedure, the rats were reinforced for a 2-s exposure (duration) of the gray cylinder, but not a 10-s duration, or vice versa. The results indicate that after hippocampal lesions, there was an initial deficit followed by complete recovery. There were no significant changes for the medial prefrontal, cortical control, or sham-operated animals. It appears that the hippocampus, but not the medial prefrontal cortex, is actively involved in representing in short-term memory temporal attribute information based on the use of markers for the beginning and end of the presence (duration) of a stimulus (object).

Effects of vagal blockade on the counterregulatory response to insulin-induced hypoglycemia in the dog

Our aim was to determine whether vagal transmission is required for the hormonal response to insulin-induced hypoglycemia in 18-h-fasted conscious dogs. Hollow coils were placed around the vagus nerves, with animals under general anesthesia, 2 wk before an experiment. On the day of the study they were perfused with -15 degrees C ethanol for the purpose of blocking vagal transmission, either coincident with the onset of insulin-induced hypoglycemia or after 2 h of established hypoglycemia. In a separate study the coils were perfused with 37 degrees C ethanol in a sham cooling experiment. The following parameters were measured: heart rate, arterial plasma glucose, insulin, pancreatic polypeptide, glucagon, cortisol, epinephrine, norepinephrine, glycerol, free fatty acids, and endogenous glucose production. In response to insulin-induced hypoglycemia (42 mg/dl), plasma glucagon peaked at a level that was double the basal level, and plasma cortisol levels quadrupled. Plasma epinephrine and norepinephrine levels both rose considerably to 2,135 +/- 314 and 537 +/- 122 pg/ml, respectively, as did plasma glycerol (330 +/- 60%) and endogenous glucose production (150 +/- 20%). Plasma free fatty acids peaked at 150 +/- 20% and then returned to basal levels by the end of the study. The hypoglycemia-induced changes were not different when vagal cooling was initiated after the prior establishment of hypoglycemia. Similarly, when vagal cooling occurred concurrently with the initiation of insulin-induced hypoglycemia (46 mg/dl), there were no significant differences in any of the parameters measured compared with the control. Thus vagal blockade did not prevent the effect on either the hormonal or metabolic responses to low blood sugar. Functioning vagal afferent nerves are not required for a normal response to insulin-induced hypoglycemia.

Inhibition of glycogenolysis enhances gluconeogenic precursor uptake by the liver of conscious dogs

We investigated the effect of inhibiting glycogenolysis on gluconeogenesis in 18-h-fasted conscious dogs with the use of intragastric administration of BAY R 3401, a glycogen phosphorylase inhibitor. Isotopic ([3-3H]glucose and [U-14C]alanine) and arteriovenous difference methods were used to assess glucose metabolism. Each study consisted of a 100-min equilibration, a 40-min control, and two 90-min test periods. Endogenous insulin and glucagon secretions were inhibited with somatostatin (0.8 microgram.kg-1.min-1), and the two hormones were replaced intraportally (insulin: 0.25 mU.kg-1.min-1; glucagon: 0.6 ng.kg-1.min-1). Drug (10 mg/kg) or placebo was given after the control period. Insulin and glucagon were kept at basal levels in the first test period, after which glucagon infusion was increased to 2.4 ng.kg-1.min-1; BAY R 3401 decreased tracer-determined endogenous glucose production [rate of glucose production (Ra): 14 +/- 1 to 7 +/- 1 mumol.kg-1.min-1] and net hepatic glucose output (11 +/- 1 to 3 +/- 2 mumol.kg-1.min-1) during test 1. It increased the net hepatic uptake of gluconeogenic substrates from 9.0 +/- 2.0 to 11.6 +/- 0.6 mumol.kg-1.min-1. Basal glycogenolysis was decreased by drug (9.1 +/- 0.7 to 1.5 +/- 0.2 mumol glucosyl U.kg-1.min-1). Placebo had no effect on Ra or the uptake of gluconeogenic precursors by the liver. The rise in glucagon increased Ra by 22 +/- 3 and by 8 +/- 2 mumol.kg-1.min-1 (at 10 min) in placebo and drug, respectively. The rise in glucagon caused little change in the net hepatic uptake (mumol.kg-1.min-1) of gluconeogenic substrates in placebo (8.2 +/- 0.6 to 9.0 +/- 1.0) but increased it markedly (11.6 +/- 0.6 to 15.4 +/- 1.0) in drug. Glucagon increased glycogenolysis by 22.1 +/- 2.5 and by 7.8 +/- 1.6 mumol.kg-1.min-1 in placebo and drug, respectively. The amount of glycogen (mumol glucosyl U/kg) synthesized from gluconeogenic carbon was four times higher in drug (48.6 +/- 9.7) than in placebo (11.3 +/- 1.7). We conclude that BAY R 3401 caused a marked reduction in basal and glucagon-stimulated glycogenolysis. As a result of these changes, there was an increase in the net hepatic uptake of gluconeogenic precursors and in glycogen synthesis.

Efficacy of arthroscopic surgery and midlaser treatments for chronic temporomandibular joint articular disc derangement following motor vehicle accident

As a result of motor vehicle accident soft-tissue injury, temporomandibular joint articular disc derangement may develop and persist despite symptomatic treatment and medication. This study reports the effectiveness of management directed at controlling the TMJ and masticatory neuromuscular pain dysfunction with a TMJ/interocclusal stabilization appliance, specific biofeedback and ultrasound therapy. Following these conservative measures residual articular disc derangement was present in some subjects who were offered arthroscopic surgery and infrared midlaser with TMJ/occlusal stabilization. Twenty subjects with residual disc derangement were randomly selected into two groups with and without arthroscopic surgery, and analyses of variance made before treatment, 12 months after conservative procedures, 3 months following arthroscopic surgery and midlaser therapy and 3 years since commencement of management. Dependent variables compared were pain-discomfort, Clinical Dysfunction Index, articular disc derangement and maximal voluntary jaw opening. Conservative management alone provided significant reduction of pain-discomfort and clinical dysfunction, while arthroscopic surgery resulted in significant reduction in articular disc derangement. The midlaser with TMJ/occlusal stabilization maintained significant improvement in the variables (p < 0.01) for both groups. The common articular deviations in form found at arthroscopy were soft tissue alteration with hyperaemia, synovitis, synovial membrane and posterior attachment folding with connective tissue hyperplasia, and disc displacement with fibrous adhesions. The Global Status Score of pain behaviour compared with residual function, confirmed the presence of greater pain before treatment commenced.

Lymphocyte subset infiltration patterns and HLA antigen status in colorectal carcinomas and adenomas

Fifty eight large bowel adenocarcinomas and 20 adenomas were studied immunohistochemically, using fresh frozen tissue sections, with regard to lymphocyte subpopulations (CD3, CD4, CD8, CD19, and CD20) in the inflammatory infiltrate and to expression of human leucocyte antigens (HLA-ABC, HLA-A2, and HLA-DR). The findings were related to differentiation and Duke's stage of carcinoma. The inflammatory infiltrate was found to have a phenotype that remained constant irrespective of the intensity of the inflammation. CD4 and CD3 positive cells predominated with fewer CD8 positive cells and a scanty diffuse CD19/20 positive cell population. CD19/20 follicular aggregates were common at the advancing margin of the carcinomas. There was no significant association with Duke's stage, differentiation or HLA status. HLA changes (ABC loss, A2 loss, and DR gain) were associated with differentiation, being more common and more extensive in poorly differentiated carcinomas. HLA-A2 loss was also associated with stage of progression of carcinoma. Inflammation associated with adenomas was found to have a similar phenotype to that associated with carcinomas. HLA changes in adenomas were uncommon, being seen in only one of our 20 cases.

Relation between stage, grade, proliferation, and expression of p53 and CD44 in adenomas and carcinomas of the colorectum

AIMS

To investigate the changes in and relations among p53, CD44 and MIB-1 expression in adenocarcinomas of the colorectum and to determine whether these changes are progressive across the adenoma-carcinoma sequence.

METHODS

Expression of p53 protein, CD44 adhesion molecule and MIB-1 proliferation antigen was detected using immunohistochemistry in 68 colorectal carcinomas and 32 colorectal adenoma. The staining characteristics were compared with degree of dysplasia in adenomas, and differentiation and Dukes' stage in carcinomas. Results were analysed and assessed using Spearman's rank correlation and independent t tests.

RESULTS

p53 staining was present in som adenomas and correlated with the degree of dysplasia. There was significantly more staining in carcinomas than adenomas and significant correlation between staining and Dukes' stage. CD44 staining was maximal in adenomas, diminished in carcinomas and was minimal in metastasising carcinomas. There was inverse correlation between p53 and CD44 expression across the adenoma-carcinoma-metastasising carcinoma sequence. MIB-1 expression was highest in carcinomas but did not correlate with either p53 or CD44 expression.

CONCLUSIONS

There are progressive changes in p53, CD44 and MIB-1 expression in adenomas and carcinomas. A combination of these tests may prove useful in assessing which patients with adenomas are at greatest risk of progressing to carcinoma.

Lobular carcinoma of the breast: cytological features supporting the diagnosis of lobular cancer

Lobular carcinomas have a distinct natural history with a better response to endocrine therapy and a higher incidence of local recurrence and are more often bilateral. The cytological diagnosis of lobular carcinoma permits a discriminating therapeutic approach with pre-operative Tamoxifen, more generous resection margins, and assessment of the contralateral breast. The cytological features of lobular cancer however are not well defined and the low cell yield from such neoplasms can result in a high false negative rate. To determine whether we could improve the pre-operative diagnosis, we reviewed the cytological features of 112 lobular carcinomas. They had small uniform sized nuclei with irregular outlines and inconspicuous nucleoli. The degree of dissociation was similar to duct carcinomas and the incidence of inadequate aspirates was no higher. We found no features that confidently diagnosed lobular cancer or its sub-types. However, using a combination of features, typing of lobular cancer on aspirated material is possible and should be attempted.

Thai Buddhist accounts of male homosexuality and AIDS in the 1980s

In this paper the author considers the scriptural background to homophobic diatribes that emerged in the mid-1980s as the HIV epidemic slowly gained recognition in Thailand. By scrutiny of references to homosexuality in the Pali canon, he concludes that the scriptures are open to widely divergent interpretations. This doctrinal malleability is expressed in the contrasting views of contemporary Thai Buddhist intellectuals. The 'traditional' view claims that homosexuality is the kammic consequence of past sexual misconduct but in itself is not sinful and does not have future kammic consequences. The other, less tolerant view is that homosexuality derives from sexual excesses and, moreover, is the cause of the contemporary AIDS epidemic. Paradoxically it is the reformist Buddhist thinkers who have adopted the latter anti-homosexual position in that they tend to place less emphasis on kamma and more on individual responsibility for life circumstances.

A comparison of large block macrosectioning and conventional techniques in breast pathology

Two techniques for the histological handling of breast specimens, namely conventional sampling using small blocks (SB) and a large block (LB) macrosectioning technique have been compared, with special emphasis on tumour size and in situ carcinoma, in an attempt to objectively demonstrate the advantages of the latter method. This is considered to be of particular importance in guiding the clinicians in their use of the many treatment modalities available for breast carcinoma. All cases were from the routine surgical caseload; 100 examined by the LB technique and 111 using conventional SB. The LB technique gave a reliable measurement of invasive carcinoma in 100% of cases compared to only 63% of SB cases. Ductal carcinoma in situ (DCIS), was found more frequently (80% versus 64%) and its extent was more easily and reliably measured in the large blocks. The extent of DCIS was significantly greater in all cases using large block techniques. Concurrent carcinomas were found more frequently in the LB series and these tumours were smaller than those in the SB series. Similar differences were noted with radial scars, and other proliferative lesions also had a higher incidence in the LB series. We conclude that the LB technique has sufficient advantages to recommend it as a standard technique in breast pathology.

Prognostic value of cytological grading of fine-needle aspirates from breast carcinomas

Because neoadjuvant therapy, including preoperative chemotherapy and tamoxifen, is becoming increasingly common for early breast cancer, it is desirable to grade tumours before surgery so that the most appropriate medical regimen can be selected. We have used a cytological grading system for ductal carcinoma of type not otherwise specified (NOS). Wet-fixed Papanicolaou-stained breast aspirates are examined for the extent of cell dissociation, cell size and uniformity, and the appearance of nucleoli, the nuclear margin, and chromatin. 377 invasive breast carcinomas were removed after preoperative diagnostic fine-needle aspiration cytology (FNAC) during the 25 months of the study. 286 tumours were ductal carcinomas NOS on histology. We established three cytological grades and found that cytological grade corresponded well with the established histological grades (Elston's modified Bloom and Richardson method). All cytological features included in the score were equally important on regression analysis. This study shows that grading of breast cancer on FNAC is feasible and reproducible. Cytological grade may substitute for histological grade, so a combination of FNAC and mammography can provide information on tumour type, grade, and size before surgery. We recommend this grading system to centres that use FNAC for the diagnosis of breast cancers.

Prevalence of Helicobacter pylori infection and its effect on symptoms and non-steroidal anti-inflammatory drug induced gastrointestinal damage in patients with rheumatoid arthritis

Non-steroidal anti-inflammatory drugs (NSAIDs) and Helicobacter (H pylori) are both associated with an increased risk of peptic ulceration and gastropathy. It is not known, however, if there is an interaction between these two agents, and thus whether or not screening for H pylori before NSAID treatment is of value. The aim of this study was to find out if H pylori potentiates the damaging effects of NSAIDs. Fifty two patients with rheumatoid arthritis requiring longterm NSAID treatment were studied. Dyspeptic symptoms were assessed according to a standardised questionnaire. Gastroscopy was performed after a one week washout period during which NSAIDs were discontinued. Gastric and duodenal mucosal damage was graded endoscopically. H pylori was identified by biopsy urease test and by histological tests. Investigations were repeated after one month's treatment with an NSAID. Patients with H pylori infection (n = 26) had a higher dyspeptic symptom score (p < 0.05). One patient with duodenal ulcer (H pylori +ve) and two with endoscopic gastritis (both H pylori +ve) were excluded from further study. Forty two subjects completed the study. After treatment there was a rise in the gastric damage score both in the H pylori +ve (p = 0.06) and the H pylori -ve (p < 0.005) groups. There was no difference in the extent of increase in grade or the final grade at the end of the treatment period between the H pylori +ve and -ve patients. It is concluded that H pylori infection is associated with increased dyspeptic symptoms in patients receiving NSAIDs but that it does not potentiate NSAID gastropathy.

Surface hydrophobicity of gastric mucosa in Helicobacter pylori infection: effect of clearance and eradication

Surface hydrophobicity of the gastric mucosa is reduced in peptic ulcer disease and Helicobacter pylori infection. This abnormality may be caused by H. pylori or may be an inherent defect. The aim of the present study was to clarify the relationship between H. pylori infection and mucosal hydrophobicity by examining the effect of eradication of the organism. H. pylori-positive patients with (n = 42) or without (n = 42) duodenal ulcer were randomized to receive ranitidine, bismuth, or bismuth plus antibiotics. Surface hydrophobicity of gastric mucosa was assessed by measurement of plateau-advancing contact angle. Measurements were performed at presentation, end of treatment, and 1 month later. Contact angle was unchanged after ranitidine (55 degrees vs. 56 degrees) but increased with bismuth (57 degrees-62 degrees; P < 0.05) and bismuth plus antibiotics (56 degrees-67 degrees; P < 0.0001). One month after treatment ended, contact angles in patients in whom H. pylori was not eradicated were not different from those before treatment (56 degrees vs. 56 degrees) but increased to a value similar to H. pylori-negative controls in patients in whom H. pylori was eradicated (56 degrees-69 degrees; P < 0.0001). It is concluded that reduced mucosal hydrophobicity in peptic ulcer disease is secondary to H. pylori infection and that this impaired mucosal defense provides a possible mechanism whereby H. pylori infection predisposes to acid/peptic digestion.

Jewish inmates: an atypical prison group

12 Jewish inmates scored significantly higher than 1497 non-Jewish inmates on a measure of intelligence, the Raven's Standard Progressive Matrices. Interview findings indicated that the present Jewish inmates were never very involved in the practice of Judaisn and were not strongly integrated into their local Jewish communities.

Genotype × environment interactions in sugarcane. I. Patterns of response across sites and crop-years in north Queensland

Responses of sugarcane genotypes across environments in north Queensland for sugar yield and its components cane yield and sugar content, were examined using pattern analysis methods. The aim was to provide information which could be used in designing efficient selection methods for sugarcane breeding programs. Of particular interest was the comparison of variation in relative performance of genotypes across sites and crop-years. Results from two series of sugarcane trials in north Queensland are presented. In the first series, 65 genotypes were evaluated at four sites and across plant, first ratoon and second ratoon crops. In the second, 52 genotypes were evaluated across four sites and across plant and first ratoon crops. Crops and years were confounded in both series. Crop-years within sites were generally more similar for genotypic responses than environments from different sites. Within most sites the relative ranking of groups of genotypes derived from cluster analysis was similar across different crop-years. However, there were some substantial differences in ranking of the groups between some sites and selection would vary if different subsets of sites were considered. There was little variation among groups in general response to ratoon crop-years. The results indicate that testing across sites is of importance. However, the similarity in information obtained across crop-years within most sites suggests there may be limited gain in testing across multiple crops or years within a particular site.

Genotype × environment interactions in sugarcane. II. Use of performance in plant cane as an indirect selection criterion for performance in ratoon crops

This study aimed to determine whether sugar yield of sugarcane genotypes in the plant crop could be used to predict relative yield in subsequent ratoon crops. Results from two series of trials, planted in 1985 and 1986, were examined. Within each series genotypes were planted at four locations and evaluated in plant, first ratoon and second ratoon crops. The genotypes used had not been selected previously in the test environments. Genetic correlations between sugar yield in plant and ratoon crop-years were moderate to high (greater than 0.65) for most locations. The relative efficiency of selection for yield in ratoon crop-years via indirect selection in the plant crop-year averaged 0.67. Realized gains from selection were compared for selection based on only plant crop results and selection based on average performance across all crop-years (the latter being the method routinely used in sugarcane breeding programs at present). In most cases the increases in realized gains in yield across independent environments brought about by considering results from more than the plant crop-year were small or non-existent. In the two series of trials, 11 and 12 of the top ranking 15 genotypes, respectively, based on mean performance across all crop-years, were also in the top 15 genotypes based on only the plant crop results. It is suggested that the testing of genotypes in only the plant crop may be appropriate in the early stages of selection in sugarcane breeding programs. Resources otherwise allocated to testing early stage material in ratoon crops may be more usefully employed elsewhere such as testing in more sites, with more replicates or more genotypes. It is emphasized, however, that this strategy may not be appropriate for highly selected populations, such as those in the final stages of selection, where genetic variance and genetic correlations between crop-years would be expected to be smaller than those obtained in this study.

Myogenic response and wall mechanics of arterioles

The magnitude of the arteriolar response to altered intraluminal pressure was assessed in isolated, cannulated vessels of the hamster cheek pouch. Microvessels were studied during various levels of smooth muscle activation, either occurring spontaneously, or resulting from the application of exogenous agonists including potassium (35 or 70 mM) and phenylephrine (1.25 or 2.50 x 10(-6) M). Diameter-pressure curves were obtained by lowering intraluminal pressure from 60 to 0 mmHg in seven steps at 3-min intervals. At an intraluminal pressure of 40 mmHg, spontaneous tone produced an average constriction to 34 +/- 2% of the maximum diameter. Step reductions in pressure typically led to reductions in the level of activation of the muscle, which resulted in a net dilation over a significant pressure range. This "myogenic response" was more effective in modifying spontaneous tone than in modifying exogenous tone. In fact, the data suggest that reduction of the intraluminal pressure to zero can result in complete inactivation of spontaneous tone. Complete inactivation was not observed when contractions were induced by exogenous agonists, however. The magnitude of the myogenic response in arterioles was consistent with a role in autoregulation, which is 2.5-fold greater than that previously reported for small arteries. The data demonstrate that in the analysis of the mechanics of submaximally activated blood vessels one must include considerations of two phenomenon: the classical stress-length behavior as determined under conditions of maximal activation, and a superimposed modification of the activation level induced by stress- or length-dependent processes. Furthermore, the findings indicate substantial differences in response when tone is spontaneous compared with the case when tone is induced by exogenous agonists.

Determination of vitamin D and retinoid activity in eggs by HPLC

Reverse phase high performance liquid chromatography (HLPC) was used to estimate the vitamin D3 content of battery and free range eggs. At the same time another HPLC technique was used to estimate the retinol activity in the battery eggs derived from the separate determination of all-trans retinol, 13-cis retinol and retinaldehyde concentrations. There was some variation in both the vitamin D3 and retinol activity in eggs over the laying year but no significance could be drawn from this. Vitamin D3 levels in 12 monthly samples each of 120 battery eggs averaged 1.2 micrograms/100 g edible portion, while the levels in each of four quarterly samples of 36 free range eggs from the London and Newcastle areas averaged 1.4 and 0.8 micrograms/100 g respectively. These differences between battery and free range eggs were not statistically significant. The average retinol activity in four samples of 120 battery eggs was calculated to be 190 micrograms/100 g, and the components of this activity were identified as 132 micrograms all-trans retinol and 21 micrograms of retinaldehyde, as well as 53 micrograms 13-cis retinol which has not previously been reported in hens' eggs.

The relation between membrane cholesterol and phospholipid and sodium efflux in erythrocytes from healthy subjects and patients with chronic cholestasis

1. The cholesterol and phospholipid content of the cell membrane and the efflux of sodium were measured in the erythrocytes of patients with chronic cholestasis and in healthy subjects. 2. The membranes from the patients contained more cholesterol and phospholipid and had a higher cholesterol/phospholipid molar ratio than the membranes from the healthy subjects. 3. The sodium efflux rate constant was reduced in the patients and this was entirely due to a reduction in the frusemide-sensitive efflux rate constant. There was no difference in either the ouabain-sensitive or the ouabain plus frusemide-resistant rate constants. 4. This reduction in the frusemide-sensitive rate constant was associated with a reduction in the erythrocyte sodium content. 5. When erythrocytes were loaded with cholesterol in vitro the frusemide-sensitive efflux rate constant was reduced by an amount similar to that observed in the patients. In addition, however, there was a reduction in the ouabain-sensitive efflux rate constant and an increase in the erythrocyte sodium content; neither of these changes was observed in the patients in vivo.

Clinical indications for echocardiography

Echocardiography is an important adjunct to clinical diagnosis. Evaluation of chamber size, estimation of left ventricular function, valvular defects, and tricuspid atresia or stenosis are among the many disorders in which it can be helpful.