scholarly journals Glutamine oxidation and utilization by rat and human oesophagus and duodenum

1999 ◽  
Vol 81 (4) ◽  
pp. 323-329 ◽  
Author(s):  
L. A. James ◽  
P. G. Lunn ◽  
S. Middleton ◽  
M. Elia

The rates of utilization and oxidation of glutamine and glucose by oesophageal and duodenal tissues have been investigated in both rats and human subjects. In the rat, glutamine utilization by oesophageal tissue was 2–3-fold lower than that in the duodenum, and this substrate contributed less than 10 % to the total oxidative metabolism of the tissue, even when glutamine was the only substrate provided. In contrast, rat duodenal tissue derived about 34 % of the total CO2 production from glutamine-C, and this contribution was not suppressed by the addition of either glucose or a mixture of the other substrates. Rates of glucose utilization and oxidation by the duodenum were lower than those for glutamine, and were significantly (P<0·001) suppressed by addition of glutamine. In both oesophageal and duodenal tissues, less than 10 % of the glutamine-C utilized was fully oxidized, approximately 60–70 % was converted to glutamate, and 30–40 % to alanine. Results obtained using human biopsy tissue samples were similar to those observed in the rat. Glutamine oxidation contributed 34 (sd 4) % of the total CO2 production by the duodenal tissue, but only 8 (sd 4) % to oesophageal tissue oxidation. The findings suggest that glutamine is not an important or preferred fuel for oesophageal tissue, whereas it is for duodenal tissue. Thus, these tissues can be expected to respond differently to glutamine administration.

Viruses ◽  
2020 ◽  
Vol 12 (12) ◽  
pp. 1412
Author(s):  
Faisal Klufah ◽  
Ghalib Mobaraki ◽  
Axel zur Hausen ◽  
Iryna V. Samarska

BK polyomavirus (BKPyV) has been associated with some high-grade and special urothelial cell carcinoma (UCC) subtypes in immunosuppressed patients. Here, we evaluated the relationship of BKPyV-positive urine cytology specimens (UCS) with UCC. A large single-institution database was retrospectively searched for UCS positive for decoy cells, suggesting BKPyV infection. These were tested for the presence of BKPyV by PCR and immunohistochemistry (IHC) in urine sediments and formalin-fixed paraffin-embedded (FFPE) tissue samples of UCC. Decoy cells were reported in 30 patients out of the database with 22.867 UCS. Of these 30 patients, 16 (53.3%) had no history of UCC. Six patients out of these 16 had a history of transplantation, 4 had a history of severe chronic medical conditions, and 6 had no chronic disease. The other fourteen patients were diagnosed with either in situ or invasive UCC of the urinary bladder (14/30; 46.6%) prior to the detection of decoy cells in the urine. Nine of these UCC patients received intravesical treatment (BCG or mitomycin) after the first presentation with UCC. However, the clinical data on the treatment of the other five UCC patients was lacking. IHC identified BKPyV-positivity in the urine samples of non-UCC and UCC patients, while no BKPyV positivity was found in FFPE tissues of primary UCCs and metastases. In addition, BKPyV-PCR results revealed the presence of BKPyV DNA in the urine of the UCC cases, yet none in the UCC tissues itself. These data strongly indicate that BKPyV reactivation is not restricted to immunosuppression. It can be found in UCS of the immunocompetent patients and may be related to the intravesical BCG or mitomycin treatment of the UCC patients.


2014 ◽  
Vol 555 ◽  
pp. 652-658 ◽  
Author(s):  
Barbu Cristian Braun ◽  
Ileana Constanta Rosca

The paper describes a new method of body equilibrium evaluation applied for different human subjects, the principal aim being to demonstrate to what extent any locomotory diseases could influence the body stability and equilibrium. The research refers to identify some persons with different locomotory diseases and to find both the influence on equilibrium and stability and if possible to improve them. Our research stage, synthesized in this paper, explains the body equilibrium evaluation in orthostatic posture done for different subjects, aged between 20 and 40 years. A number of 10 relevant persons were considered to be evaluated, 2 of them having some locomotory diseases. The first person presents any neuro-motor stability problems in case of long standing case. The other person has both Achilles tendons torn and operated. All subjects were tested in orthostatic posture, in 3 distinct positions, using a Kistler force plate. The experiments referred to the body mass center (COM) displacement in sagittal and lateral planes, representing an interesting characteristic for its equilibrium. It was shown that the person with diseases affecting stability presented a loss of equilibrium when standing for 10-20 seconds, i.e. higher COM displacements in both planes reported to the other tested subjects.


1984 ◽  
Vol 55 (3) ◽  
pp. 687-696 ◽  
Author(s):  
Rick M. Gardner ◽  
Terry L. Corbin ◽  
Janelle S. Beltramo ◽  
Gary S. Nickell

Cooperation in pairs of rats playing the prisoner's dilemma game was investigated. Six pairs of animals were taught to make either cooperative or uncooperative responses by running to one or the other end of a T-maze. Two T-mazes were joined together such that animals could respond simultaneously. Animals were run under conditions in which visual communication was present and absent. Mutually uncooperative responses were the most common and mutually cooperative behaviors the least preferred. Introduction of a barrier between the mazes, which removed visual communication between pairs, sharply accentuated uncooperative behavior. Similarities of the present findings to results with human subjects and the implications of using game theory for studying cooperative behavior in animals are discussed.


1988 ◽  
Vol 66 (2) ◽  
pp. 534-537 ◽  
Author(s):  
Caroline M. Pond ◽  
Christine A. Mattacks

The gross mass, mean adipocyte volume, and hexokinase and phosphofructokinase activities of blubber and internal adipose tissue were measured from fin whales (Balaenoptera physalus) caught in the North Atlantic west of Iceland. Fin whale adipocytes are smaller but more numerous than predictions from allometric equations relating adipose tissue structure to body mass, but the deviations are no greater than those of some terrestrial mammals, including humans. Significant activity of the glycolytic enzymes was measured from all adipose tissue samples except those around the eyeball; the activities of hexokinase and phosphofructokinase measured at room temperature are only slightly lower in the blubber than in the internal adipose depots. There was little evidence for metabolic correlates of the site-specific differences in the structure and chemistry of blubber. The highest capacity for glucose utilization was measured in adipose tissue from depots in the neck and the thorax, both of which may contain thermogenic tissue in neonates.


1984 ◽  
Vol 247 (3) ◽  
pp. R418-R426
Author(s):  
P. H. Gander ◽  
R. E. Kronauer ◽  
C. A. Czeisler ◽  
M. C. Moore-Ede

Our two-oscillator model was originally designed to describe the circadian rhythms of human subjects maintained in temporal isolation. The performance of this model in response to simulated environmental synchronizing cycles (zeitgebers) is examined here. Six distinct types of synchronization are demonstrated between the x oscillator (postulated to regulate the core temperature rhythm), the y oscillator (postulated to regulate the rest-activity rhythm), and z (the zeitgeber). Four types of synchronization are identifiable, if we consider only the periods of the three oscillators. Both x and y may be synchronized by z; either may synchronize with z while the other exhibits a different period; or x, y, and z may each show different periods. Two further classes of synchronization are discernible when phase criteria are taken into account. When either x or y is on the verge of desynchronizing from the other two oscillators, it undergoes periodic phase modulations while retaining the common overall period. The type of synchronization observed depends on the periods of x, y, and z and on the strength of the z drive. The effects of modifying each of these parameters have been systematically investigated by simulation, and model performance is summarized in terms of range of entrainment "maps." These constitute extensive sets of predictions about expected patterns of entrainment of the core temperature and rest-activity rhythms of human subjects exposed to various environmental zeitgebers. Experimental data are available against which model predictions can be tested.


1987 ◽  
Vol 253 (4) ◽  
pp. E418-E427
Author(s):  
D. A. Pelligrino ◽  
D. J. Miletich ◽  
R. F. Albrecht

The effect on cortical cerebral glucose utilization (CMRglu) of intracerebral insulin administration in awake goats was studied. The insulin was superfused in a mock cerebrospinal fluid (CSF) solution employing chronically implanted cranial windows. Two windows were implanted bilaterally: one window over an equivalent portion of each parietal cortex. With one window used to deliver insulin/CSF and the other used to simultaneously deliver CSF alone (control), changes in CMRglu were assessed using a modification of a sequential 2-[3H]- then 2-[14C]deoxy-D-glucose (2DG) technique originally described by Altenau and Agranoff (Brain Res. 153: 375-381, 1978). Initial experiments employing 125I-insulin demonstrated that the superfusion procedure increased insulin levels only in the outer 1 mm of cortical tissue exposed to insulin containing perfusate. Additional preliminary evaluations, using conditions known to alter CMRglu, generally established that present methods were adequate to induce and detect CMRglu changes. However, it was also shown experimentally and using a mathematical model that 2-[3H]DG test/control tissue ratios could be influenced by subsequent changes in CMRglu and the dephosphorylation rate. Thus 3H ratios could not be used to establish preexperimental test/control CMRglu relationships as the originally devised model assumed but could be employed to indicate changes in dephosphorylation. The mathematical model allowed for improved estimates of CMRglu changes from 2-[14C]DG/2-[3H]DG test over control tissue ratios. Even with these corrections, insulin was estimated to cause no more than an 8-15% increase in cortical CMRglu. A very limited role for insulin, at least in cerebral cortical metabolic regulation, is thus indicated.


1990 ◽  
Vol 63 (5) ◽  
pp. 999-1009 ◽  
Author(s):  
Z. Kapoula ◽  
L. M. Optican ◽  
D. A. Robinson

1. In these experiments, postsaccadic ocular drift was induced by postsaccadic motion of the visual scene. In the most important case, the scene was moved in one eye but not the other. Six human subjects viewed the interior of a full-field hemisphere filled with a random-dot pattern. During training, eye movements were recorded by the electrooculogram. A computer detected the end of every saccade and immediately moved the pattern horizontally in the same or, in different experiments, in the opposite direction as the saccade. The pattern motion was exponential with an amplitude of 25% of the size of the antecedent saccade and a time constant of 50 ms. Before and after 3-4 h of such training, movements of both eyes were measured simultaneously by the eye coil-magnetic field method while subjects looked between stationary targets for calibration, explored the visual pattern with saccades, or made saccades in the dark to measure the effects of adaptation on postsaccadic ocular drift. The amplitude of this drift was expressed as a percentage of the size of the antecedent saccade. 2. In monocular experiments, subjects viewed the random-dot pattern with one eye. The other eye was patched. With two subjects, the pattern drifted backward in the direction opposite to the saccade; with the third, it drifted onward. The induced ocular drift was exponential, always in the direction to reduce retinal image motion, had zero latency, and persisted in the dark. After training, drift in the dark changed by 6.7% in agreement with our prior study with binocular vision, which produced a change of 6.0%. 3. In a dichoptic arrangement, one eye regarded the moveable random-dot pattern; the other, through mirrors, saw a different random-dot pattern (with similar spacing, contrast, and distance) that was stationary. These visual patterns were not fuseable and did not evoke subjective diplopia. In this case, the induced change in postsaccadic drift in the same three subjects was only 4.8%. In all cases the changes in postsaccadic drift were conjugate--they obeyed Hering's law. 4. Normal human saccades are characterized by essentially no postsaccadic drift in the abducting eye and a pronounced onward drift (approximately 4%) in the adducting eye. After training, this abduction-adduction asymmetry was preserved in the light and dark with monocular or dichoptic viewing, indicating again that all adaptive changes were conjugate. 5. When the subjects viewed the adapting stimulus after training, the zero-latency, postsaccadic drift always increased from levels in the dark.(ABSTRACT TRUNCATED AT 400 WORDS)


2019 ◽  
Vol 5 (2) ◽  
pp. 231-249 ◽  
Author(s):  
Neni Panourgiá

The human-scape of Europe has changed irrevocably since the intensification of extractive economies and the wars that they have engendered from the 1990s onwards. Greece, as a country, and Athens as its major city, have been caught in this web off-guard, even though any astute politician could have seen the changes coming. This altered human-scape comprises human subjects involved in a dynamic dialectic of recognition ‐ recognition of the self and the other, and recognition of the self by the self, in the process producing new subjectivities and hardening already existing ones. I am looking at three emblematic points in Athens ‐ Exarcheia, the Athenian Trilogy and Gerani ‐ through the eyes and the words of (primarily) anarchist and leftist activists, subjects who have been at the forefront of resistance both to hegemonic and authoritarian politics since the 1960s and to their extractive economies. Through raw material that I collected in the summer and winter of 2018 I examine the positions taken by these subjects as they try to re-negotiate their politics of recognition in a landscape that is constantly shifting.


1984 ◽  
Vol 247 (2) ◽  
pp. E190-E197
Author(s):  
L. A. Leiter ◽  
M. Grose ◽  
J. F. Yale ◽  
E. B. Marliss

Catecholamines have multiple metabolic and fluid-electrolyte as well as cardiovascular effects, and their levels in plasma respond to alterations in nutrient and sodium intakes. Plasma norepinephrine, epinephrine, and dopamine were measured in 12 obese nondiabetic subjects before and after 400 kcal/day diets of either protein or glucose, followed by total fasting, and then by hypocaloric refeeding, each for 14-day periods. Measurements were made in the supine and upright posture and during and after 6-10 min of exhaustive exercise at 80% maximal VO2. Sodium intake varied with the nutrients ingested, being markedly decreased with the 400 kcal/day diets and fasting. Norepinephrine levels were higher in fasting than base line while subjects were lying or standing and after recovery from exercise. Those of epinephrine were elevated on standing. No differences were found after the 400 kcal/day diets, with protein and glucose yielding equivalent results. In contrast, refeeding was associated with lower norepinephrine levels than all other diets while subjects were lying or standing and after recovery from exercise. Peak levels of norepinephrine and epinephrine with exercise were indistinguishable among diets. Fasting was associated with lower systolic and diastolic blood pressures and lower responses to standing and exercise than base line, whereas upright heart rate was greater and that during exercise less than base line. Significant though less extensive changes occurred with the other diets. Thus both electrolyte status and nutrient intakes interact to determine net catecholamine responses, and the former seem to override the latter.(ABSTRACT TRUNCATED AT 250 WORDS)


1981 ◽  
Vol 61 (2) ◽  
pp. 311-318 ◽  
Author(s):  
J. P. FAY ◽  
K.-J. CHENG ◽  
J. W. COSTERTON

Alkaline phosphatase (APase) activity was assayed in tissue samples from the gastrointestinal tract (GIT) of newborn Holstein calves, and of 3- to 10-mo-old calves fed on milk only or starter-grower ration plus alfalfa hay. Statistical analysis of APase activity from different regions of the GIT showed effects of diet and site (P < 0.01) and an interaction of diet × site (P < 0.01) on APase activity. APase was high in the reticulo-rumen: intermediate in the omasum and the intestinal region: and low in the tongue, esophagus and abomasum. Within the same organ. APase differed considerably according to the location of the sites. Calves fed the fiber-containing diet had higher APase than those fed milk only. APase activity in the reticulo-rumen was much lower in newborn calves than in older calves, but in the other regions of the GIT, values were similar for the two groups. The effect of fasting on APase activity in rumen and abomasum walls of 20 yearling Hereford and Angus bulls fed on two different diets was also studied. In most cases, fasting decreased wall-associated APase activities. Interactions for breed × diet × site (P < 0.01), for breed × fasting × site (P < 0.01), and for diet × fasting × site (P < 0.05) on rumen APase activity, and for breed × diet × fasting (P < 0.01) on abomasum APase activity, were detected in this experiment. These variations in APase activity within the digestive tract are discussed in relation to the absorption capacity, degree of abrasion, and degree of keratinization of the tissues involved.


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