Fasting Feeding Research Articles

GC-MS metabolic profiling reveals fructose-2,6-bisphosphate regulates branched chain amino acid metabolism in the heart during fasting.

As an insulin sensitive tissue, the heart decreases glucose usage during fasting. This response is mediated, in part, by decreasing phosphofructokinase-2 (PFK-2) activity and levels of its product fructose-2,6-bisphosphate. However, the importance of fructose-2,6-bisphosphate in the fasting response on other metabolic pathways has not been evaluated. The goal of this study is to determine how sustaining cardiac fructose-2,6-bisphosphate levels during fasting affects the metabolomic profile. Control and transgenic mice expressing a constitutively active form of PFK-2 (GlycoHi) were subjected to either 12-h fasting or regular feeding. Animals (n = 4 per group) were used for whole-heart extraction, followed by gas chromatography-mass spectrometry metabolic profiling and multivariate data analysis. Principal component analysis displayed differences between Control and GlycoHi groups under both fasting and fed conditions while a clear response to fasting was observed only for Control animals. However, pathway analysis revealed that these smaller changes in the GlycoHi group were significantly associated with branched-chain amino acid (BCAA) metabolism (~ 40% increase in all BCAAs). Correlation network analysis demonstrated clear differences in response to fasting between Control and GlycoHi groups amongst most parameters. Notably, fasting caused an increase in network density in the Control group from 0.12 to 0.14 while the GlycoHi group responded oppositely (0.17-0.15). Elevated cardiac PFK-2 activity during fasting selectively increases BCAAs levels and decreases global changes in metabolism.

Daily Variation in Feeding and Ingestive Behaviour of Sheep and Goats Grazing and Browsing on Grass- Legume Pastures

The objective of this study was to investigate the feeding and ingestive behaviours of sheep and goats grazing on grass-legume pastures. Three 2-year female Nguni x Boer goats and three 3-year female Damara sheep were randomly allocated to grass-Lespedeza cuneata (grass-Lc) and grass-Leucaena leucocephala (grass-Ll) pastures. Times spent on browsing, grazing and idling were recorded from 0700 to 1600 h every 2 minutes for 3 consecutive days. Ingestive behaviour of each animal was observed for 10 minutes at 1000, 1200 and 1400 h for 6 days. Bite count and bite weight were used to determine intake rates during browsing. Goats spent 3.24 and 3.93 times longer than sheep in browsing, while sheep spent 2.75 and 2.27 times longer in grazing than goats on grass-Lc than grass-Ll pastures, respectively. Goats idled for longer periods than sheep on both pastures. Sheep had faster bite rates than goats, while Lespedeza cuneata elicited lower bite rates than L. leucocephala. Fastest feeding and bite rates were observed at mid day (1200 h) and lowest during the afternoon (1400 h). Intake rates of fresh herbage are higher at mid day than in the morning and afternoon. In conclusion, based on time spent browsing, L. leucocephala is better preferred as a forage browse compared to L. cuneata.

A Measurement System for Time Constant of Thermocouple Sensor Based on High Temperature Furnace

In dynamic temperature measurement, thermocouple sensors are widely used, and their dynamic characteristics directly affect the accuracy of the test results. So before applying thermocouple sensors to dynamic temperature measurement, their dynamic characteristics should be obtained, and their dynamic performance parameters should be analyzed. The time constant is the most important dynamic parameter, which reflects the response speed of a thermocouple sensor. Therefore, it is necessary to measure the time constant. The time constant is closely related to the heat transfer mode, so the heat transfer environment of the time constant measurement system should be similar to the application environment of thermocouple sensor. When using the thermocouple to measure the temperature in various kilns, the heat transfer is mainly through the radiative mode, and existing equipment, such as constant temperature water/oil tank, shock wave tube and other devices, cannot be used to measure the time constant to reflect scenarios in actual measurement applications. Therefore, this paper proposed a new method to measure the time constant of the thermocouple by improved high temperature furnace. In the system, the high temperature furnace was used to generate the stable temperature field, and the fast feed device was used to insert the thermocouple into the high temperature furnace and generates the ramp temperature excitation. The temperature can reach 1500 °C in the furnace, and the temperature error in uniform temperature field is ±1 °C. Finally, the time constant of a K-type thermocouple was measured, and the uncertainty of the measurement result was analyzed.

How do pregnant and lactating women, and young children, experience religious food restriction at the community level? A qualitative study of fasting traditions and feeding behaviors in four regions of Ethiopia

Maternal and child feeding behaviors are often rooted in family and sociocultural context, making these an important point of inquiry for improving nutrition and health over the life course. The present study explored the practice of fasting during religious periods in relation to eating patterns of pregnant and lactating women and young children in four regions of Ethiopia, a nation which has experienced rapid economic growth and marked improvement in health and nutrition outcomes over the last two decades. Qualitative data collection and analysis at community level illustrated conflicting areas of understanding and practice related to diets of children and pregnant and lactating women during fasting times, potentially leading to gaps in nutrition. Community participants described different understandings of fasting requirements for these vulnerable populations and associated social norms and doxa, not always in accordance with religious texts or published guidance. Useful behavior change strategies may be developed through these results to address the potential barriers to appropriate feeding patterns for pregnant and lactating women and young children in Ethiopia. This will include continuing to work with communities and religious leaders to clarify that religious doctrine promotes improved nutrition outcomes.

Intermittent Fasting, Insufficient Sleep, and Circadian Rhythm: Interaction and Effects on the Cardiometabolic System

Sleep, circadian rhythms, and fasting/feeding are important factors that affect cardiometabolic function. Here, we review recent studies that assessed the role of intermittent fasting, short sleep duration, and circadian rhythm disruption, as well as their interactions, on the risk of cardiometabolic dysfunction. The cardiometabolic system is sensitive to sleep, circadian rhythms, and fasting/feeding patterns. Recent data show that these factors may influence each other and hence, directly or indirectly affect cardiometabolic risk. Fasting/feeding schedules and mealtimes may cause misalignment of the circadian system resulting in several cardiometabolic disturbances. Recent data reveal that intermittent fasting (IF) improves several cardiometabolic indicators in both laboratory animals and humans maintained on IF diets during alternate day fasting, diurnal IF, or time-restricted feeding. However, most of the human studies recruited a modest number of participants and did not control for several confounding factors that may have affected the measurement of cardiometabolic parameters, such as sleep duration and timing, energy expenditure, and light exposure. Current evidence shows that IF, sleep, and circadian rhythms can affect cardiometabolic risk both individually or collectively. IF, adequate sleep, and matching mealtimes with the circadian clock improve several cardiometabolic parameters. More extensive human studies that assess the interaction between the three factors in the general population are needed to complement the currently available short-term laboratory-based human studies.

Extremely fast feeding strikes are powered by elastic recoil in a seahorse relative, the snipefish, Macroramphosus scolopax.

Among over 30 000 species of ray-finned fishes, seahorses and pipefishes have a unique feeding mechanism whereby the elastic recoil of tendons allows them to rotate their long snouts extremely rapidly in order to capture small elusive prey. To understand the evolutionary origins of this feeding mechanism, its phylogenetic distribution among closely related lineages must be assessed. We present evidence for elastic recoil-powered feeding in snipefish (Macroramphosus scolopax) from kinematics, dynamics and morphology. High-speed videos of strikes show they achieve extremely fast head and hyoid rotational velocities, resulting in rapid prey capture in as short a duration as 2 ms. The maximum instantaneous muscle-mass-specific power requirement for head rotation in snipefish was above the known vertebrate maximum, which is evidence that strikes are not the result of direct muscle power. Finally, we show that the over-centre conformation of the four-bar linkage mechanism coupling head elevation to hyoid rotation in snipefish can function as a torque reversal latch, preventing the head from rotating and providing the opportunity for elastic energy storage. The presence of elastic recoil feeding in snipefish means that this high-performance mechanism is not restricted to the Syngnathidae (seahorses and pipefish) and may have evolved in parallel.

On Alternative Approaches to Design of Corporate Feeds for Low-Sidelobe Microstrip Linear Arrays

Two design approaches, illustrated by simulations and measurements, aiming at a systematic computer-aided design of printed circuit feeds for low-sidelobe microstrip antenna arrays are described. The novelty of these approaches resides in identification of the optimal feed architectures with subsequent simulation-based optimization of the feed and array aperture dimensions. In this communication, we consider microstrip corporate feeds (CFs) realizing nonuniform amplitude excitation of linear arrays of microstrip patch antennas. Two types of the microstrip CFs are considered: with equal power split junctions and with unequal power split junctions. For each feed type, we identify candidate prototypes of feed architectures using numerical optimization of the corresponding fast feed models. Subsequently, the architectures are implemented as microstrip subcircuits within the antenna array electromagnetic (EM) models. For the sake of comparison, the antenna array circuits are defined with the same linear array of microstrip patch antennas featuring the half-wavelength element spacing, and implemented on the same microstrip substrates. Finally, the EM models are tuned—using simulation-based optimization techniques—to ensure an appropriate input reflection coefficient and minimum sidelobe levels. Selected optimal designs of antenna array circuits with 12 microstrip patches and different feeds are manufactured and measured.

Skeletal Muscle Clock Is Essential for Nutrient-Sensing and Interorgan Metabolic Fuel Partitioning

The circadian clock exerts temporal control in metabolism and its disruption leads to the development of diabetes and obesity. Tissue-intrinsic clock circuits are integral components of global metabolic homeostasis, although how they sense nutrient signals to orchestrate metabolic flux is not clear. Skeletal muscle is major site for metabolic substrate oxidation, and its utilization of glucose and fatty acid depends on availability of nutrients accompanying feeding-fasting transitions. Interestingly, nearly 30% of rhythmic transcripts in skeletal muscle belongs to metabolism. By generating a mouse model with myocyte-selective ablation of the clock transcription activator Bmal1, here we show that cell-autonomous muscle clock plays an essential role in coordinating nutrient utilization with feeding-fasting induced cycles. Bmal1 in skeletal muscle was robustly induced by feeding, and its loss markedly impaired feeding-induced switch to glucose metabolism from fatty acid utilization. As a result, Bmal1-deficient muscle displays nearly 50% reduction of glucose oxidation whereas fatty acid oxidation was enhanced, resembling a constant fasting state. This metabolic shift was accompanied by muscle fiber type switching to an oxidative phenotype, and led to a remarkable resistance to hepatic lipid accumulation induced by prolonged fasting or high-fat diet feeding. In contrast, systemic fasting glucose levels in muscle Bmal1-deficient mice was elevated, which is due to a failure of suppressing hepatic glucose output as revealed by hyperinsulinemic-euglycemic glucose clamp study. Collectively, our results reveal a novel function of the Bmal1-driven muscle clock as a key metabolic sensor that coordinates metabolic fuel oxidation with oscillatory nutrient availability in fasting-feeding cycles. This temporal mechanism in orchestrating global nutrient flux may contribute to metabolic abnormalities induced by circadian misalignment. Disclosure K. Ma: None. S. Chatterjee: None. H. Yin: None.

Surface Engineering of SiC through Nanogrinding and CMP

Processing silicon carbide (SiC) wafers to achieve an epi-ready quality finish typically requires many lapping and a very long chemical mechanical polishing (CMP) steps. In this paper, we report the thinning down of 6” SiC wafers to sub-nanometer surface finish in less than two hours. Three process steps (rough grinding, nanogrinding and CMP) are involved. Rough grinding thins down the wafer with fast feed rate and maintain excellent flatness. Nanogrinding allows the surface finish to improve down to a few nanometers. The last CMP step provides high planarization efficiency. Overall the throughput of SiC processing is substantially increased over current market solutions.

Food motivation in horses appears stable across different test situations

Food motivation may influence an animal’s performance in food-rewarded learning tasks. Nevertheless, food is often used as a positive reinforcer in learning tasks to investigate cognitive abilities of farm animals, and to test effects of various treatments, such as environmental enrichment, on animal cognition. However, any treatment that affects food motivation may also influence performance in food-rewarded learning tasks. Assesment of individual food motivation is therefore relevant for many studies where cognitve abilities are measured through food-rewarded tasks. This study is an initial attempt to assess food motivation in horses. Twenty-three horses were tested in two experiments designed to evaluate food motivation. The first test was a lever test (LT) where the horses had to press a lever for a food reward with an increasing work ratio of three presses after each two trials. In the second test, the horses were required to cross a barrier to reach a food bucket (CB). The height of the barrier was increased (5 cm) after each trial. The results were compared with the time used to eat 1.5 kg oats (free feeding, FF). The highest achieved workload in LT (i.e. number of lever presses) and CB (i.e. height of barrier), latency to finish eating (min:sec) in FF, as well as behavioural (e.g. nibbling, pawing, alertness) and physiological parameters (heart rate) and salivary cortisol) were analysed. Positive correlations were found between maximum workload in LT and CB (r = 0.49, p = 0.02). The latency to finish eating in FF correlated negatively with maximum workload in LT (r = −0.47, p = 0.02), i.e. fast feed consumption corresponded to a high workload. There were no statistical differences between pre-test and post-test levels of salivary cortisol, suggesting that the test situations were not perceived as stressful by the horses. The results indicate correlations in horses’ food motivation across different test situations and thus the simple free feeding test appears to be the easiest way to assess individual food motivation in horses in comparison to time-consuming operant tests.

Effects of fasted vs fed‐state exercise on performance and post‐exercise metabolism: A systematic review and meta‐analysis

The effects of nutrition on exercise metabolism and performance remain an important topic among sports scientists, clinical, and athletic populations. Recently, fasted exercise has garnered interest as a beneficial stimulus which induces superior metabolic adaptations to fed exercise in key peripheral tissues. Conversely, pre-exercise feeding augments exercise performance compared with fasting conditions. Given these seemingly divergent effects on performance and metabolism, an appraisal of the literature is warranted. This review determined the effects of fasting vs pre-exercise feeding on continuous aerobic and anaerobic or intermittent exercise performance, and post-exercise metabolic adaptations. A search was performed using the MEDLINE and PubMed search engines. The literature search identified 46 studies meeting the relevant inclusion criteria. The Delphi list was used to assess study quality. A meta-analysis and meta-regression were performed where appropriate. Findings indicated that pre-exercise feeding enhanced prolonged (P=.012), but not shorter duration aerobic exercise performance (P=.687). Fasted exercise increased post-exercise circulating FFAs (P=.023) compared to fed exercise. It is evidenced that pre-exercise feeding blunted signaling in skeletal muscle and adipose tissue implicated in regulating components of metabolism, including mitochondrial adaptation and substrate utilization. This review's findings support the hypothesis that the fasted and fed conditions can divergently influence exercise metabolism and performance. Pre-exercise feeding bolsters prolonged aerobic performance, while seminal evidence highlights potential beneficial metabolic adaptations that fasted exercise may induce in peripheral tissues. However, further research is required to fully elucidate the acute and chronic physiological adaptations to fasted vs fed exercise.

Expression Patterns of Host Inflammatory Cytokine Genes during Infestation with Haemaphysalis longicornis, a Zoonotic Vector, in Blood Sucking Periods

Tick saliva is critically important for continuous attachment to the host, blood feeding for days, and transmission of tick-borne pathogens. To characterize the patterns of inflammatory cytokine gene expression during its attachment and blood sucking time, peripheral blood samples of rabbits infested with Haemaphysalis longicornis ticks were collected at different intervals. Blood histamine concentration was evaluated as well as gene encoding IFN-γ, TNF-α, IL-2, IL-6, IL-4, and IL-10 were compared with non-infested rabbits. Blood histamine concentration of tick-infested rabbits during fast feeding time was significantly higher than that of non-infested rabbits. In both nymph and adult tick infested rabbits, expression of TNF-α and IFN-γ genes were decreased significantly (P<0.05), while expression of IL-4, IL-6, and IL-10 were increased 1.3 to 7 folds in adult infested rabbits with the exception of IL-6 that was significantly (P<0.05) decreased in nymph infested rabbits. IL-2 was not expressed in either nymph or adult infestation. H. longicornis saliva is capable of modulate host responses through a complex correlation with histamine and Th1, Th2 mediated cytokines that suppress the inflammatory responses directed toward inflammatory mediators introduced into the host during tick feeding.

Glass Microsphere‐Supported Giant Vesicles for the Observation of Self‐Reproduction of Lipid Boundaries

AbstractGrowth and division experiments on phospholipid boundaries were carried out using glass microsphere‐supported phospholipid (DOPC) giant vesicles (GVs) fed with a fatty acid solution (oleic acid) at two distinct feeding rates. Both fast and slow feeding methods produced daughter GVs. Under slow feeding conditions the membrane growth process (evagination, buds, filaments) was observed in detail by fluorescence microscopy. The density difference between supported mother vesicles and newly formed daughter vesicles allowed their easy separation. Mass spectrometric analysis of the resulting mother and daughter GVs showed that the composition of both vesicle types was a mixture of original supported phospholipids and added fatty acids reflecting the total composition of amphiphiles after the feeding process. Thus, self‐reproduction of phospholipid vesicles can take place under preservation of the lipid composition but different aggregate size.

Glass Microsphere-Supported Giant Vesicles for the Observation of Self-Reproduction of Lipid Boundaries.

Growth and division experiments on phospholipid boundaries were carried out using glass microsphere-supported phospholipid (DOPC) giant vesicles (GVs) fed with a fatty acid solution (oleic acid) at two distinct feeding rates. Both fast and slow feeding methods produced daughter GVs. Under slow feeding conditions the membrane growth process (evagination, buds, filaments) was observed in detail by fluorescence microscopy. The density difference between supported mother vesicles and newly formed daughter vesicles allowed their easy separation. Mass spectrometric analysis of the resulting mother and daughter GVs showed that the composition of both vesicle types was a mixture of original supported phospholipids and added fatty acids reflecting the total composition of amphiphiles after the feeding process. Thus, self-reproduction of phospholipid vesicles can take place under preservation of the lipid composition but different aggregate size.

A5221 - Fast track feeding after revisional bariatric surgery is associated with reduced length of stay

A5221 - Fast track feeding after revisional bariatric surgery is associated with reduced length of stay

Can the Discrepancy between Locally and Globally Derived Neutral Hydrogen Mass Functions be Explained by a Varying Value of M ⋆?

Abstract I investigate whether it is possible to reconcile the recent Arecibo Legacy Fast Arecibo L-band Feed Array (ALFALFA) observation that the neutral hydrogen mass function (HIMF) across different galactic densities has the same, non-flat, faint-end slope, with observations of isolated galaxies and many galaxy groups that show their HIMFs to have flat faint-end slopes. I find that a fairly simple model in which the position of the knee in the mass function of each individual group is allowed to vary is able to account for both of these observations. If this model reflects reality, the ALFALFA results point to an interesting “conspiracy” whereby the differing group HIMFs always sum up to form global HIMFs with the same faint-end slope in different environments. More generally, this result implies that global environmental HIMFs do not necessarily reflect the HIMFs in individual groups belonging to that environment and cannot be used to directly measure variations in group-specific HIMFs with environment.

Analysis of powder rheometry of FT4: Effect of particle shape

Particle shape has a strong influence on bulk powder flow and its associated rheology. It promotes mechanical arching and adversely affects fast feeding and dosing. We use the FT4 powder rheometer of Freeman Technology to experimentally characterise the particle flow asa function of the shear strain rate, and to predict its dynamics for rod-shape particles using the discrete element method. The results show a strong realignment of the orientation of particles in the horizontal plane as the bed is sheared by the blade motion. The flow energy required for agitating a bed of rodlike particles is much larger than that of spheres and it increases with the aspect ratio, due to a combined effect of the coordination number and excluded volume. The flowability of rodlike particles can be improved by the addition of spheres, and can be well predicted by the mathematical model developed in this work. The bulk friction coefficient of the binary mixture is a linear function of the volume fraction of its components. The flow energy correlates well with the shear stress arising in front of the blade, considering the effect of the bulk friction coefficient.

The characteristics of salivary pepsin in patients with severe motor and intellectual disabilities

PurposeThe aim of the present study was to determine the utility of measuring the salivary pepsin level (SPL) as an objective assessment of gastroesophageal reflux disease (GERD) in severe motor and intellectual disabilities (SMID) patients. Subjects and methodsThis prospective study included 26 SMID patients who underwent simultaneous 24-h multichannel intraluminal impedance pH measurement (pH/MII) and SPL evaluation. The enrolled patients were divided into GERD (+) or GERD (−) groups according to the pH/MII findings. The age, gender and pH/MII parameters were compared between the two groups. A correlation analysis was also conducted for the SPL following early-morning fasting and post-enteral feeding and the age, gender, presence of gastrostomy and tracheostomy and pH/MII parameters. The SPL was compared between the two sampling groups. ResultsFifteen patients were classified as GERD (+), and 11 patients were classified as GERD (−). The mean SPL following early-morning fasting and post-enteral feeding among all patients were 104.3 (median: 38, 25th and 75th percentile: 12, 361) ng/ml and 222.2 (median: 152:0, 500) ng/ml, respectively. Regarding positivity, 76.9% and 73.1% of SPL values in early-morning fasting and post-enteral feeding SMID patients, respectively, were positive (≧16ng/ml). The SPL following early-morning fasting demonstrated a weak but significant positive correlation with age. In contrast, we noted no correlation between the pH/MII parameters and the SPL for either the early-morning fasting or post-enteral feeding patients, and no significant difference in the SPL was observed between the GERD (+) and (−) patients. ConclusionsThe present study showed that a high proportion of SMID patients had a relatively high SPL, regardless of the presence of GERD. The SPL in SMID patients might be affected by several distinctive factors in addition to gastroesophageal reflux.

Reproduction and larval biology in tunas, and the importance of restricted area spawning grounds

Tunas show a wide variety of life history strategies, spatial distributions and migratory behaviors, yet they share a common trait of spawning only in tropical and sub-tropical regions. The warm-water tuna species generally show significant overlap between spawning and feeding grounds, and longer spawning seasons of several months to near year-round. In contrast, the cool-water bluefin tunas migrate long distances between feeding and spawning grounds, and may spawn over periods as short as 2 months. Here, we examine the spatial distributions of tuna larvae in the world’s oceans, and examine interspecific differences in the light of adult behaviors and larval ecology. We discuss the links between larval tuna and their oceanographic environments and relate these to current knowledge of larval growth, feeding and trophodynamics, with a focus on the better-studied bluefin tunas. We show that larval tunas have moderate to fast growth rates and selective feeding habits, and thus appear to be adapted for survival in warm, oligotrophic seas. We also examine the challenges of sustainably managing species which migrate across multiple management boundaries to reach spatio-temporally restricted spawning grounds and discuss the previous and future anthropogenic impacts on tuna spawning areas.

Malaria parasite molecule entices mosquitoes

Carbon dioxide emitted from humans and other mammals is a well-known homing beacon for blood-thirsty female mosquitoes. But mosquitoes responsible for spreading the parasite that causes malaria, Plasmodium falciparum, are more attracted to already infected animals. Ingrid Faye and colleagues at Stockholm University now report that (E)-4-hydroxy-3-methyl-but-2-enyl pyrophosphate (HMBPP), a molecule made by P. falciparum, explains this mysterious attraction that helps spread malaria. They showed that mosquitoes preferred to consume red blood cells laced with HMBPP, doubling their intake compared with HMBPP-free cells. “It was a very fast feeding and they filled their guts enormously,” Faye says. Blood cells infected with P. falciparum caused a similar increase in feeding (Science 2017, DOI: 10.1126/science.aah4563). By analyzing the volatiles emitted from red blood cells, the researchers showed that HMBPP raised CO2 emissions by 16%. The molecule also increased the release of aldehydes, such as octanal, non...