Proximal Active Optical Sensing Operational Improvement for Research Using the CropCircle ACS-470, Implications for Measurement of Normalized Difference Vegetation Index (NDVI)

Active radiometric reflectance is useful to determine plant characteristics in field conditions. However, the physics of silicone diode-based sensing are temperature sensitive, where a change in temperature affects photoconductive resistance. High-throughput plant phenotyping (HTPP) is a modern approach using sensors often mounted to proximal based platforms for spatiotemporal measurements of field grown plants. Yet HTPP systems and their sensors are subject to the temperature extremes where plants are grown, and this may affect overall performance and accuracy. The purpose of this study was to characterize the only customizable proximal active reflectance sensor available for HTPP research, including a 10 °C increase in temperature during sensor warmup and in field conditions, and to suggest an operational use approach for researchers. Sensor performance was measured at 1.2 m using large titanium-dioxide white painted field normalization reference panels and the expected detector unity values as well as sensor body temperatures were recorded. The white panel reference measurements illustrated that individual filtered sensor detectors subjected to the same thermal change can behave differently. Across 361 observations of all filtered detectors before and after field collections where temperature changed by more than one degree, values changed an average of 0.24% per 1 °C. Recommendations based on years of sensor control data and plant field phenotyping agricultural research are provided to support ACS-470 researchers by using white panel normalization and sensor temperature stabilization.

Assessing Drought and Heat Stress-Induced Changes in the Cotton Leaf Metabolome and Their Relationship With Hyperspectral Reflectance

The study of phenotypes that reveal mechanisms of adaptation to drought and heat stress is crucial for the development of climate resilient crops in the face of climate uncertainty. The leaf metabolome effectively summarizes stress-driven perturbations of the plant physiological status and represents an intermediate phenotype that bridges the plant genome and phenome. The objective of this study was to analyze the effect of water deficit and heat stress on the leaf metabolome of 22 genetically diverse accessions of upland cotton grown in the Arizona low desert over two consecutive years. Results revealed that membrane lipid remodeling was the main leaf mechanism of adaptation to drought. The magnitude of metabolic adaptations to drought, which had an impact on fiber traits, was found to be quantitatively and qualitatively associated with different stress severity levels during the two years of the field trial. Leaf-level hyperspectral reflectance data were also used to predict the leaf metabolite profiles of the cotton accessions. Multivariate statistical models using hyperspectral data accurately estimated (R ² > 0.7 in ∼34% of the metabolites) and predicted (Q ² > 0.5 in 15-25% of the metabolites) many leaf metabolites. Predicted values of metabolites could efficiently discriminate stressed and non-stressed samples and reveal which regions of the reflectance spectrum were the most informative for predictions. Combined together, these findings suggest that hyperspectral sensors can be used for the rapid, non-destructive estimation of leaf metabolites, which can summarize the plant physiological status.

Arthropod Demography, Distribution, and Dispersion in a Novel Trap-Cropped Cotton Agroecosystem

Vernonia [Vernonia galamensis (Cass.) Less.] (Asterales: Asteraceae) was examined as a potential trap crop for the cotton (Gossypium hirsutum L., Malvales: Malvaceae) arthropod complex. Four rows of vernonia were embedded within a 96-row cotton field. The abundance of true bug pests, true bug predators, and spiders were determined by whole-plant and sweep net sampling procedures during the early, middle, and late phases of the cotton-growing season. The census data showed that the arthropods had a strong preference for the vernonia trap crop throughout the cotton-growing season. The movement of the arthropods from the trap crop into cotton was also measured using the protein immunomarking technique as a mark-capture procedure. The arthropods inhabiting the vernonia trap crop were marked directly in the field with a broadcast spray application of egg albumin (protein) during each phase of the study. In turn, the captured specimens were examined for the presence of the mark by an egg albumin-specific enzyme-linked immunosorbent assay. Very few marked specimens were captured beyond the vernonia trap crop 1, 3, and 6 d after each marking event. The arthropods' strong attraction and fidelity to vernonia indicate that it could serve as a trap crop for cotton pests and a refuge for natural enemies.

A data workflow to support plant breeding decisions from a terrestrial field-based high-throughput plant phenotyping system

Field-based high-throughput plant phenotyping (FB-HTPP) has been a primary focus for crop improvement to meet the demands of a growing population in a changing environment. Over the years, breeders, geneticists, physiologists, and agronomists have been able to improve the understanding between complex dynamic traits and plant response to changing environmental conditions using FB-HTPP. However, the volume, velocity, and variety of data captured by FB-HTPP can be problematic, requiring large data stores, databases, and computationally intensive data processing pipelines. To be fully effective, FB-HTTP data workflows including applications for database implementation, data processing, and data interpretation must be developed and optimized. At the US Arid Land Agricultural Center in Maricopa Arizona, USA a data workflow was developed for a terrestrial FB-HTPP platform that utilized a custom Python application and a PostgreSQL database. The workflow developed for the HTPP platform enables users to capture and organize data and verify data quality before statistical analysis. The data from this platform and workflow were used to identify plant lodging and heat tolerance, enhancing genetic gain by improving selection accuracy in an upland cotton breeding program. An advantage of this platform and workflow was the increased amount of data collected throughout the season, while a main limitation was the start-up cost.

The Endocannabinoid System Alleviates Pain in a Murine Model of Cancer-Induced Bone Pain

Metastatic breast cancer is prevalent worldwide, and one of the most common sites of metastasis is long bones. Of patients with disease, the major symptom is pain, yet current medications fail to adequately result in analgesic efficacy and present major undesirable adverse effects. In our study, we investigate the potential of a novel monoacylglycerol lipase (MAGL) inhibitor, MJN110, in a murine model of cancer-induced bone pain. Literature has previously demonstrated that MAGL inhibitors function to increase the endogenous concentrations of 2-arachydonylglycerol, which then activates CB1 and CB2 receptors to inhibit inflammation and pain. We demonstrate that administration of MJN110 significantly and dose dependently alleviates spontaneous pain behavior during acute administration compared with vehicle control. In addition, MJN110 maintains its efficacy in a chronic-dosing paradigm over the course of 7 days without signs of receptor sensitization. In vitro analysis of MJN110 demonstrated a dose-dependent and significant decrease in cell viability and proliferation of 66.1 breast adenocarcinoma cells to a greater extent than KML29, an alternate MAGL inhibitor, or the CB2 agonist JWH015. Chronic administration of the compound did not appear to affect tumor burden, as evidenced by radiograph or histologic analysis. Together, these data support the application for MJN110 as a novel therapeutic for cancer-induced bone pain. SIGNIFICANCE STATEMENT: Current standard of care for metastatic breast cancer pain is opioid-based therapies with adjunctive chemotherapy, which have highly addictive and other deleterious side effects. The need for effective, non-opioid-based therapies is essential, and harnessing the endogenous cannabinoid system is proving to be a new target to treat various types of pain conditions. We present a novel drug targeting the endogenous cannabinoid system that is effective at reducing pain in a mouse model of metastatic breast cancer to bone.

Chlorophyll fluorescence imaging captures photochemical efficiency of grain sorghum (Sorghum bicolor) in a field setting

BACKGROUND

Photosynthesis is one of the most important biological reactions and forms the basis of crop productivity and yield on which a growing global population relies. However, to develop improved plant cultivars that are capable of increased productivity, methods that can accurately and quickly quantify photosynthetic efficiency in large numbers of genotypes under field conditions are needed. Chlorophyll fluorescence imaging is a rapid, non-destructive measurement that can provide insight into the efficiency of the light-dependent reactions of photosynthesis.

RESULTS

To test and validate a field-deployed fluorescence imaging system on the TERRA-REF field scanalyzer, leaves of potted sorghum plants were treated with a photosystem II inhibitor, DCMU, to reduce photochemical efficiency (F_V/F_M). The ability of the fluorescence imaging system to detect changes in fluorescence was determined by comparing the image-derived values with a handheld fluorometer. This study demonstrated that the imaging system was able to accurately measure photochemical efficiency (F_V/F_M) and was highly correlated (r = 0.92) with the handheld fluorometer values. Additionally, the fluorescence imaging system was able to track the decrease in photochemical efficiency due to treatment of DCMU over a 7 day period.

CONCLUSIONS

The system's ability to capture the temporal dynamics of the plants' response to this induced stress, which has comparable dynamics to abiotic and biotic stressors found in field environments, indicates the system is operating correctly. With the validation of the fluorescence imaging system, physiological and genetic studies can be undertaken that leverage the fluorescence imaging capabilities and throughput of the field scanalyzer.

Use of Body-Mounted Cameras to Enhance Data Collection: An Evaluation of Two Arthropod Sampling Techniques

A study was conducted that compared the effectiveness of a sweepnet versus a vacuum suction device for collecting arthropods in cotton. The study differs from previous research in that body-mounted action cameras (B-MACs) were used to record the activity of the person conducting the arthropod collections. The videos produced by the B-MACs were then analyzed with behavioral event recording software to quantify various aspects of the sampling process. The sampler's speed and the number of sampling sweeps or vacuum suctions taken over a fixed distance (12.2 m) of cotton were two of the more significant sampling characteristics quantified for each method. The arthropod counts obtained, combined with the analyses of the videos, enabled us to estimate arthropod sampling efficiency for each technique based on fixed distance, time, and sample unit measurements. Data revealed that the vacuuming was the most precise method for collecting arthropods in the relatively small cotton research plots. However, data also indicates that the sweepnet method would be more efficient for collecting most of the cotton-dwelling arthropod taxa, especially if the sampler could continuously sweep for at least 1 min or ≥80 m (e.g., in larger research plots). The B-MACs are inexpensive and non-cumbersome, the video images generated are outstanding, and they can be archived to provide permanent documentation of a research project. The methods described here could be useful for other types of field-based research to enhance data collection efficiency.

Deploying a Proximal Sensing Cart to Identify Drought-Adaptive Traits in Upland Cotton for High-Throughput Phenotyping

Field-based high-throughput phenotyping is an emerging approach to quantify difficult, time-sensitive plant traits in relevant growing conditions. Proximal sensing carts represent an alternative platform to more costly high-clearance tractors for phenotyping dynamic traits in the field. A proximal sensing cart and specifically a deployment protocol, were developed to phenotype traits related to drought tolerance in the field. The cart-sensor package included an infrared thermometer, ultrasonic transducer, multi-spectral reflectance sensor, weather station, and RGB cameras. The cart deployment protocol was evaluated on 35 upland cotton (Gossypium hirsutum L.) entries grown in 2017 at Maricopa, AZ, United States. Experimental plots were grown under well-watered and water-limited conditions using a (0,1) alpha lattice design and evaluated in June and July. Total collection time of the 0.87 hectare field averaged 2 h and 27 min and produced 50.7 MB and 45.7 GB of data from the sensors and RGB cameras, respectively. Canopy temperature, crop water stress index (CWSI), canopy height, normalized difference vegetative index (NDVI), and leaf area index (LAI) differed among entries and showed an interaction with the water regime (p < 0.05). Broad-sense heritability (H²) estimates ranged from 0.097 to 0.574 across all phenotypes and collections. Canopy cover estimated from RGB images increased with counts of established plants (r = 0.747, p = 0.033). Based on the cart-derived phenotypes, three entries were found to have improved drought-adaptive traits compared to a local adapted cultivar. These results indicate that the deployment protocol developed for the cart and sensor package can measure multiple traits rapidly and accurately to characterize complex plant traits under drought conditions.

Resistance to Multiple Soil-Borne Pathogens of the Pacific Northwest, USA Is Colocated in a Wheat Recombinant Inbred Line Population

Soil-borne pathogens of the Pacific Northwest decrease yields in both spring and winter wheat. Pathogens of economic importance include Fusarium culmorum, Pratylenchus neglectus, P. thornei, and Rhizoctonia solani AG8. Few options are available to growers to manage these pathogens and reduce yield loss, therefore the focus for breeding programs is on developing resistant wheat cultivars. A recombinant inbred line population, LouAu (MP-7, NSL 511036), was developed to identify quantitative trait loci (QTL) associated with resistance to P. neglectus and P. thornei This same population was later suspected to be resistant to F. culmorum and R. solani AG8. This study confirms partial resistance to F. culmorum and R. solani AG8 is present in this population. Six major and 16 speculative QTL were identified across seven measured traits. Four of the six major QTL were found within the same genomic region of the 5A wheat chromosome suggesting shared gene(s) contribute to the resistance. These QTL will be useful in breeding programs looking to incorporate resistance to soil-borne pathogens in wheat cultivars.

Quantitative hopanoid analysis enables robust pattern detection and comparison between laboratories

Hopanoids are steroid-like lipids from the isoprenoid family that are produced primarily by bacteria. Hopanes, molecular fossils of hopanoids, offer the potential to provide insight into environmental transitions on the early Earth, if their sources and biological functions can be constrained. Semiquantitative methods for mass spectrometric analysis of hopanoids from cultures and environmental samples have been developed in the last two decades. However, the structural diversity of hopanoids, and possible variability in their ionization efficiencies on different instruments, have thus far precluded robust quantification and hindered comparison of results between laboratories. These ionization inconsistencies give rise to the need to calibrate individual instruments with purified hopanoids to reliably quantify hopanoids. Here, we present new approaches to obtain both purified and synthetic quantification standards. We optimized 2-methylhopanoid production in Rhodopseudomonas palustris TIE-1 and purified 2Me-diplopterol, 2Me-bacteriohopanetetrol (2Me-BHT), and their unmethylated species (diplopterol and BHT). We found that 2-methylation decreases the signal intensity of diplopterol between 2 and 34% depending on the instrument used to detect it, but decreases the BHT signal less than 5%. In addition, 2Me-diplopterol produces 10× higher ion counts than equivalent quantities of 2Me-BHT. Similar deviations were also observed using a flame ionization detector for signal quantification in GC. In LC-MS, however, 2Me-BHT produces 11× higher ion counts than 2Me-diplopterol but only 1.2× higher ion counts than the sterol standard pregnane acetate. To further improve quantification, we synthesized tetradeuterated (D4) diplopterol, a precursor for a variety of hopanoids. LC-MS analysis on a mixture of (D4)-diplopterol and phospholipids showed that under the influence of co-eluted phospholipids, the D4-diplopterol internal standard quantifies diplopterol more accurately than external diplopterol standards. These new quantitative approaches permit meaningful comparisons between studies, allowing more accurate hopanoid pattern detection in both laboratory and environmental samples.

Implications of iron deficiency/anemia on the classification of diabetes using HbA1c

Background/Objectives:

Nonglycemic factors like iron deficiency (ID) or anemia may interfere with classification of diabetes and prediabetes using hemoglobin A1c (HbA1c). However, few population-based studies of diabetes in areas with endemic ID/anemia have been conducted. We aimed to determine how mutually exclusive categories of ID alone, anemia alone and iron-deficiency anemia (IDA) were each associated with prediabetes and diabetes prevalence using fasting blood glucose (FBG) versus HbA1c in a population-based study of adults with endemic ID/anemia.

Subjects/Methods:

We used data from the China Health and Nutrition Survey, a longitudinal, population-based study across 228 communities within nine provinces of China. This analysis included 7308 adults seen in the 2009 survey aged 18–75 years. We used descriptive and covariate-adjusted models to examine relative risk of prediabetes and diabetes using FBG alone, HbA1c alone, HbA1c and FBG, or neither (normoglycemia) by anemia alone, ID alone, IDA or normal iron/hemoglobin.

Results:

Approximately 65% of individuals with diabetes in our sample were concordantly classified with diabetes using both FBG and HbA1c, while 35% had a discordant diabetes classification: they were classified using either FBG or HbA1c, but not both. Fewer participants with ID alone versus normal iron/hemoglobin were classified with diabetes using HbA1c only. From covariate-adjusted, multinomial regression analyses, the adjusted prevalence of prediabetes using HbA1c only was 22% for men with anemia alone, but 13% for men with normal iron/hemoglobin. In contrast, the predicted prevalence of prediabetes using HbA1c only was 8% for women with ID alone, compared with 13% for women with normal iron/hemoglobin.

Conclusions:

These findings suggest potential misclassification of diabetes using HbA1c in areas of endemic ID/anemia. Estimating diabetes prevalence using HbA1c may result in under-diagnosis in women with ID and over-diagnosis in men with anemia.

Methyl 2-(5,5-dimethyl-1,3,2-dioxa-borinan-2-yl)-4-nitro-benzoate

The six-membered boronate ester ring of the title compound, C₁₃H₁₆BNO₆, adopts an envelope conformation with the C atom bearing the dimethyl substituents at the flap. The O—B—C—C torsion angles between the boronate group and the benzene ring are 72.5 (2) and 81.0 (2)°. The 4-nitro­benzoate unit adopts a slightly twisted conformation, with dihedral angles between the benzene ring and the nitrate and methyl ester groups of 17.5 (2) and 14.4 (3)°, respectively. In the crystal, inversion-related pairs of mol­ecules show weak π–π stacking inter­actions [centroid–centroid distance = 4.0585 (9) Å and inter­planar spacing = 3.6254 (7) Å].

Practical applications of averages and differences of Friedel opposites

The practical use of the average and difference intensities of Friedel opposites at different stages of structure analysis has been investigated. It is shown how these values may be properly and practically used at the stage of space-group determination. At the stage of least-squares refinement, it is shown that increasing the weight of the difference intensities does not improve their fit to the model. The correct form of the coefficients for a difference electron-density calculation is given. In the process of structure validation, it is further shown that plots of the observed and model difference intensities provide an objective method to evaluate the fit of the data to the model and to reveal insufficiencies in the intensity measurements. As a further tool for the validation of structure determinations, the use of the Patterson functions of the average and difference intensities has been investigated and their clear advantage demonstrated.

Detection and Discrimination of Pratylenchus neglectus and P. thornei in DNA Extracts from Soil

A species-specific polymerase chain reaction (PCR) method was developed to detect and identify the root-lesion nematodes Pratylenchus neglectus and P. thornei from soil. A primer set was designed from Pratylenchus 28S rRNA gene sequences of the D3 expansion domain. Primer specificity was confirmed with 23 isolates of 15 nematode species and other plant-parasitic and non-plant-parasitic nematodes typically present in the soil communities, and with six fungal species commonly associated with wheat root rot. DNA obtained using a commercially available kit and a method developed in our laboratory gave comparable amplification. PCR conditions were optimized and the two species were differentiated by PCR products of 144 bp for P. neglectus and 288 bp for P. thornei. With this assay, we detected a single juvenile in 1 g of sterile, inoculated soil. Examination of 30 field soil samples revealed that this method was applicable to a range of soils naturally infested with these two pathogens in Oregon. This PCR-based method is rapid, efficient, and reliable, does not require expertise in nematode taxonomy and morphology, and could be used as a rapid diagnostic tool for commercial and research applications for disease forecasting and management.

Muscle long-chain acyl CoA esters and insulin resistance

A common observation in animal models and in humans is that accumulation of muscle triglyceride is associated with the development of insulin resistance. In animals, this is true of genetic models of obesity and nutritional models of insulin resistance generated by high-fat feeding, infusion of lipid, or infusion of glucose. Although there is a strong link between the accumulation of triglycerides (TG) in muscle and insulin resistance, it is unlikely that TG are directly involved in the generation of muscle insulin resistance. There are now other plausible mechanistic links between muscle lipid metabolites and insulin resistance, in addition to the classic substrate competition proposed by Randle's glucose-fatty acid cycle. The first step in fatty acid metabolism (oxidation or storage) is activation to the long-chain fatty acyl CoA (LCACoA). This review covers the evidence suggesting that cytosolic accumulation of this active form of lipid in muscle can lead to impaired insulin signaling, impaired enzyme activity, and insulin resistance, either directly or by conversion to other lipid intermediates that alter the activity of key kinases and phosphatases. Actions of fatty acids to bind specific nuclear transcription factors provide another mechanism whereby different lipids could influence metabolism.

The role of lipids in the pathogenesis of muscle insulin resistance and beta cell failure in type II diabetes and obesity

This review considers evidence for, and putative mechanisms of, lipid-induced muscle insulin resistance. Acute free fatty acid elevation causes muscle insulin resistance in a few hours, with similar muscle lipid accumulation as accompanies more prolonged high fat diet-induced insulin resistance in rodents. Although causal relations are not as clearcut in chronic human insulin resistant states such as obesity and type 2 diabetes, it is now recognised that muscle lipids also accumulate in these states. The classic Randle glucose-fatty acid cycle is only one of a number of mechanisms by which fatty acids might influence muscle glucose metabolism and insulin action. A key factor is seen to be accumulation of muscle long chain acyl CoAs, which could alter insulin action via several mechanisms including chronic activation of protein kinase C isoforms or ceramide accumulation. These interactions are fundamental to understanding metabolic effects of new insulin "sensitizers", e.g. thiazolidinediones, which alter lipid metabolism and improve muscle insulin sensitivity in insulin resistant states. Recent work has also pointed to a possible role of lipids in beta cell deterioration ("lipotoxicity") associated with type 2 diabetes.

Triglycerides, fatty acids and insulin resistance--hyperinsulinemia

There is now much interest in the mechanisms by which altered lipid metabolism might contribute to insulin resistance as is found in Syndrome X or in Type II diabetes. This review considers recent evidence obtained in animal models and its relevance to humans, and also likely mechanisms and strategies for the onset and amelioration of insulin resistance. A key tissue for development of insulin resistance is skeletal muscle. Animal models of Syndrome X (eg high fat fed rat) exhibit excess accumulation of muscle triglyceride coincident with development of insulin resistance. This seems to also occur in humans and several studies demonstrate increased muscle triglyceride content in insulin resistant states. Recently magnetic resonance spectroscopy has been used to demonstrate that at least some of the lipid accumulation is inside the muscle cell (myocyte). Factors leading to this accumulation are not clear, but it could derive from elevated circulating free fatty acids, basal or postprandial triglycerides, or reduced muscle fatty acid oxidation. Supporting a link with adipose tissue metabolism, there appears to be a close association of muscle and whole body insulin resistance with the degree of abdominal obesity. While causal relationships are still to be clearly established, there are now quite plausible mechanistic links between muscle lipid accumulation and insulin resistance, which go beyond the classic Randle glucose-fatty acid cycle. In animal models, dietary changes or prior exercise which reduce muscle lipid accumulation also improve insulin sensitivity. It is likely that cytosolic accumulation of the active form of lipid in muscle, the long chain fatty acyl CoAs, is involved, leading to altered insulin signalling or enzyme activities (eg glycogen synthase) either directly or via chronic activation of mediators such as protein kinase C. Unless there is significant weight loss, short or medium term dietary manipulation does not alter insulin sensitivity as much in humans as in rodent models, and there is considerable interest in pharmacological intervention. Studies using PPARgamma receptor agonists, the thiazolidinediones, have supported the principle that reduced muscle lipid accumulation is associated with increased insulin sensitivity. Other potent systemic lipid-lowering agents such as PPARalpha receptor agonists (eg fibrates) or antilipolytic agents (eg nicotinic acid analogues) might improve insulin sensitivity but further work is needed, particularly to clarify implications for muscle metabolism. In conclusion, evidence is growing that excess muscle and liver lipid accumulation causes or exacerbates insulin resistance in Syndrome X and in Type II diabetes; development of strategies to prevent this seem very worthwhile.

Validation of a nutrition screening tool: testing the reliability and validity

BACKGROUND

The aim of this study was to validate a nutrition screening tool for use in South Manchester University Hospitals Trust.

METHOD

A sample of 100 patients was selected from medical, surgical and elderly care wards. To test the reliability of the screening tool, nurses and dietitians completed the screening tool on the same patient. These results were compared for interobserver error to determine whether the screening tool was reproducible with different observers. To ascertain if the screening tool identified malnutrition at ward level, four markers commonly used to assess nutritional status were collected. These included body mass index (BMI), mid upper arm circumference MUAC, percentage weight loss, and energy intake calculated from the patient's first full day in hospital and expressed as a percentage of their estimated average requirements (EAR).

RESULTS

There was a 95% level of agreement between nurses and dietitians within +/-3. The screening tool had a sensitivity level of 78% and a specificity of 52% when compared to all patients who had one or more markers indicating malnutrition. This association was found to be statistically significant (P < 0.005).

CONCLUSION

The screening tool is reliable when completed by different observers and is valid for wide scale nutritional assessment. The screening tool identifies an acceptable number of patients who are malnourished but overestimates patients at moderate risk.

Acyl-CoA inhibition of hexokinase in rat and human skeletal muscle is a potential mechanism of lipid-induced insulin resistance

There are strong correlations between impaired insulin-stimulated glucose metabolism and increased intramuscular lipid pools; however, the mechanism by which lipids interact with glucose metabolism is not completely understood. Long-chain acyl CoAs have been reported to allosterically inhibit liver glucokinase (hexokinase IV). The aim of the present study was to determine whether long-chain acyl CoAs inhibit hexokinase in rat and human skeletal muscle. At subsaturating glucose concentrations, 10 micromol/l of the three major long-chain acyl-CoA species in skeletal muscle, palmitoyl CoA (16:0), oleoyl CoA (18:1, n = 9), and linoleoyl CoA (18:2, n = 6), reduced hexokinase activity of rat skeletal muscle to 61 +/- 3, 66 +/- 7, and 57 +/- 5% of control activity (P < 0.005), respectively. The inhibition was concentration-dependent (P < 0.005) with 5 pmol/l producing near maximal inhibition. Human skeletal muscle hexokinase was also inhibited by long-chain acyl CoAs (5 pmol/l palmitoyl CoA decreased activity to 75 +/- 6% of control activity, P < 0.005). Inhibition of hexokinase in rat and human muscle by long-chain acyl CoAs was additive to the inhibition of hexokinase by glucose-6-phosphate (an allosteric inhibitor of hexokinase). This inhibition of skeletal muscle hexokinase by long-chain acyl CoA suggests that increases in intramuscular lipid metabolites could interact directly with insulin-mediated glucose metabolism in vivo by decreasing the rate of glucose phosphorylation and decreasing glucose-6-phosphate concentrations.

Effects of individual fatty acids on glucose uptake and glycogen synthesis in soleus muscle in vitro

Soleus muscle strips from Wistar rats were preincubated with palmitate in vitro before the determination of insulin-mediated glucose metabolism in fatty acid-free medium. Palmitate decreased insulin-stimulated glycogen synthesis to 51% of control in a time- (0-6 h) and concentration-dependent (0-2 mM) manner. Basal and insulin-stimulated glucose transport/phosphorylation also decreased with time, but the decrease occurred after the effect on glycogen synthesis. Preincubation with 1 mM palmitate, oleate, linoleate, or linolenate for 4 h impaired glycogen synthesis stimulated with a submaximal physiological insulin concentration (300 microU/ml) to 50-60% of the control response, and this reduction was associated with impaired insulin-stimulated phosphorylation of protein kinase B (PKB). Preincubation with different fatty acids (all 1 mM for 4 h) had varying effects on insulin-stimulated glucose transport/phosphorylation, which was decreased by oleate and linoleate, whereas palmitate and linolenate had little effect. Across groups, the rates of glucose transport/phosphorylation correlated with the intramuscular long-chain acyl-CoA content. The similar effects of individual fatty acids on glycogen synthesis but different effects on insulin-stimulated glucose transport/phosphorylation provide evidence that lipids may interact with these two pathways via different mechanisms.

Selective chronic regulation of GLUT1 and GLUT4 content by insulin, glucose, and lipid in rat cardiac muscle in vivo

The glucose transporter GLUT1 may play a more important role in cardiac than in skeletal muscle, but its regulation is unclear. During fasting, cardiac GLUT1 declines in the presence of low plasma insulin and glucose and high nonesterified fatty acid (NEFA) levels, whereas GLUT4 is unchanged. We investigated insulin, glucose, and NEFA levels as regulatory factors of cardiac GLUT content in chronically cannulated rats. Fasting rats were infused for 24 h with saline or insulin (2 rates) while plasma glucose was equalized by a glucose clamp; final transporter content was compared with a fed control group. There was a close association of GLUT1 content with insulin (r2 = 0.83, P < 0.001), with GLUT1 varying over a threefold range, under equivalent fasting glycemic conditions (plasma glucose, 5.1 +/- 0.1 mM). Maintenance of fed insulin levels during fasting prevented the GLUT1 fall (P < 0.01), whereas hyperinsulinemia (117 +/- 10 mU/l) led to significant overexpression of GLUT1 (155 +/- 12% of control, P < 0.01). When high glucose (7.6 +/- 0.1 mM) or high NEFA (0.76 +/- 0.05 mM) levels accompanied the hyperinsulinemia, upregulation of GLUT1 was blocked. GLUT1 content correlated with an estimate of cardiac glucose clearance across the groups. Cardiac GLUT4 content, hexokinase, and acyl-CoA synthase activities were unaffected by fasting, insulin, or substrate manipulation. In conclusion, insulin preferentially upregulates GLUT1 (but not GLUT4) in a dose-dependent manner in cardiac muscle in vivo, and substrate supply modulates this response, since upregulation can be effectively blocked by increased glucose or lipid availability. Therefore, both insulin exposure and energy status of cardiac muscle may be important determinants of cardiac GLUT1 expression.

Mechanical ventilation increases microvascular permeability in oleic acid-injured lungs

The pulmonary pathology for which a patient receives ventilatory support may increase the risk of developing barotrauma, because an underlying disease process may weaken the vasculature and render the lung more susceptible to damage by mechanical ventilation. We determined the response of isolated young rabbit lungs to mechanical ventilation after oleic acid (OA) injury. New Zealand White rabbits (0.7-1.3 kg) were anesthetized with pentobarbital sodium (30 mg/kg), tracheotomized, and exsanguinated. The heart and lungs were isolated and perfused with autologous blood at a constant flow. The capillary filtration coefficient (Kf,c, in ml.min-1.cmH2O-1.100 g wet wt-1) and pulmonary arterial (Ppa) and venous pressures were determined before and 30 and 60 min after oleic acid administration (OA group; 0.2 ml into the venous reservoir), ventilation alone (Vent group; peak inspiratory pressure = 25 cmH2O), or oleic acid combined with ventilation (OA + Vent group). Ppa transiently increased by 4.21 +/- 0.822 cmH2O after OA administration but then returned to approximately control values. Baseline Kf,c values for OA (0.288 +/- 0.042), Vent (0.296 +/- 0.035), or OA + Vent (0.276 +/- 0.028) groups were not significantly different from each other. Kf,c after either OA administration (0.45 +/- 0.066) or Vent (0.35 +/- 0.75) were not significantly different from each other or from baseline measurements. In the group ventilated after OA administration (OA + Vent), Kf,c (0.883 +/- 0.148) increased significantly from baseline (P less than 0.001) and was significantly different from all other treatment groups. We conclude that the combination of minimal OA injury and ventilation was more deleterious to the lung than either one alone.

Genetic influences on spatial ability: transmission in an extended kindred

Transmission of six spatial tests, Card Rotations, Cube Comparisons, Group Embedded Figures, Hidden Patterns, Mental Rotations, and portable Rod and Frame, is examined among 73 members in four generations of an extended kindred. Nonadditive genetic variance is substantial for one of the six tests, Card Rotations. Whether this nonadditive genetic variance is due to a major autosomal gene is equivocal based on results from segregation and linkage analysis. There is no evidence for genetic variance for Mental Rotations or Hidden Patterns, in contrast to previous findings suggesting major gene involvement (Ashton et al., 1979). If spatial ability is due, in part, to an autosomal major gene, the gene has variable expression (reflected in different tests) or genetic heterogeneity is pronounced.

Salt and blood pressure: the triangular hypothesis

If an unselected sample includes individuals whose blood pressure is sensitive to their salt intake and individuals whose blood pressure is not sensitive, then the superposition of these two sub-populations in a scatterplot of individuals' blood pressures against their salt intakes could give a triangular distribution. The non-correlation in the insensitives would obscure the correlation expected in the sensitives. This hypothesis justifies truncation of such data to test for correlation between blood pressure and salt intake among only the individuals in the higher range of blood pressures observed. No criterion of salt sensitivity is needed. The analysis should succeed if salt intake makes a major contribution to hypertension and would be improved if other putative causes were factored out.

Fixed and reproducible orthostatic proteinuria: results of a 20-year follow-up study

A 20-year follow-up evaluation of young men with fixed and reproducible orthostatic proteinuria showed no evidence of progressive renal disease. Follow-up information was obtained on 43 of the original 64 patients and detailed information was secured on 36. All had normal renal function and only six patients continued to show qualitative proteinuria. The prevalence of hypertension found was similar to that of a comparably aged group of the general population. The 20-year prognosis of patients with fixed and reproducible orthostatic proteinuria is excellent.

Studies on antibody levels to Brucella abortus, Toxoplasma gondii and Leptospira serogroups in sera collected by the National Serum Bank during 1974-1976

The New Zealand National Serum Bank is a collection of human sera consisting predominantly of specimens taken from healthy New Zealand blood donors. The studies presented here were designed to assess the antibody levels in two urban centres to Brucella abortus, Toxoplasma gondii and several Leptospiral serogroups including all those found in New Zealand. In none of the sera could complement fixing leptospiral antibodies be detected. There was evidence of low level immunity to both Toxoplasma gondii and Brucella abortus.

Studies of visual synthesis: integration of fragments into forms

On each of a series of trials, subjects indicated whether two sequential visual forms were the same or different. The first form was presented on some trials as a whole within a square frame and on others in fragments--with its perimeter distributed over two or three frames. The subject was instructed to visualize the first form as a whole in any case, and study time (ST) for the form was recorded. The same/different reaction time (RT) for the second, test, form (always presented in one frame) was also recorded. Experiment 1 revealed that variables affecting ST had little effect on RT and indicated that subjects can process fragments of forms in parallel. Experiment 2 demonstrated that the representation encoded from fragments differed from one generated from long-term memory. Whereas the first experiments used wholes as test stimuli, in Experiments 3 and 4 on some trials, fragments were used. In Experiment 3, RT was facilitated when a test fragment coincided with an intact fragment of the first stimulus. This indicated that first stimuli were not encoded as complete wholes. In Experiment 4, irregular forms were used as stimuli, and the RT data departed from predictions of the parallel model. Taken as a whole, the results place constraints on the codes produced by constructive processes acting to synthesize fragments into wholes.

Studies of visual synthesis: Integration of fragments into forms

On each of a series of trials, subjects indicated whether two sequential visual forms were the same or different. The first form was presented on some trials as a whole within a square frame and on others in fragments--with its perimeter distributed over two or three frames. The subject was instructed to visualize the first form as a whole in any case, and study time (ST) for the form was recorded. The same/different reaction time (RT) for the second, test, form (always presented in one frame) was also recorded. Experiment 1 revealed that variables affecting ST had little effect on RT and indicated that subjects can process fragments of forms in parallel. Experiment 2 demonstrated that the representation encoded from fragments differed from one generated from long-term memory. Whereas the first experiments used wholes as test stimuli, in Experiments 3 and 4 on some trials, fragments were used. In Experiment 3, RT was facilitated when a test fragment coincided with an intact fragment of the first stimulus. This indicated that first stimuli were not encoded as complete wholes. In Experiment 4, irregular forms were used as stimuli, and the RT data departed from predictions of the parallel model. Taken as a whole, the results place constraints on the codes produced by constructive processes acting to synthesize fragments into wholes.

Diagnosis and management of arterial stenosis causing hypertension after successful renal transplantation

Renal artery stenosis causing hypertension has been noted in 11 patients after successful renal transplantations. We believe that all patients with moderate to severe post-transplant hypertension should be evaluated with angiography and selective renin determinations. However, because of definite risk to the graft we believe that operative intervention should be undertaken only if hypertension is uncontrolled or if declining renal function is present and attributable to the stenosis.

Placenta previa and preeclampsia complicating the management of renal transplant patients

Presented are three patients who have delivered full-term normal infants after renal transplants from living related donors. One patient had a placenta previa with excessive vaginal hemorrhage. Another patient manifested preeclampsia. Management of these and other complications should be aggressive and thorough with special precautions taken to preserve graft function. In our patients, pregnancy was not harmful to the renal transplant. No fetal complications from immunosuppressive drugs were noted and the patients' dosage requirements did not change. Counseling regarding family planning is essential in patients with renal transplant.

Evidence suggesting persistence of nephritogenic immunopathologic mechanisms in patients receiving renal allografts

Direct immunofluorescent (IF) examinations and elutions were performed on native kidneys and allografts of 24 patients undergoing renal transplantation. Immunoglobulins (Ig) were detected by IF on native kidneys of 12 of the 24; 11 of the 12 later had Ig localized to allograft glomeruli by direct IF. In addition, three other patients also developed Ig deposition on allograft glomeruli, although direct IF of native kidneys was negative. Elution studies indicated: (a) that linear Ig deposition on allograft glomeruli was the result of antiglomerular basement membrane (GBM) antibodies, (b) Ig localizing to allograft glomeruli in many of these patients was the result of persistent immunopathogenetic mechanisms existing at the time of allograft placement, and (c) occasionally, kidneys negative for Ig localization by direct IF contain elutable nephritogenic antibodies.

Uricolytic enzymes in liver of the Dipnoan Protopterus aethiopicus

The enzymes uricase, allantoinase, and allantoicase have been measured in liver preparations of the African lungfish Protopterus aethiopicus. The levels for these enzymes in lungfish liver suggest that the amount of urea formed in vivo in Protopterus via a uricolytic pathway may be greater than that derived via the Ornithine-urea cycle. The operation of a "purine cycle" in lungfish liver is proposed.