Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0040822 (tremor)
 18,428 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Platelet concentrates (PC) were stored in plastic bags with continuous shaking at 4, 22, and 37 C. Various metabolic parameters were examined over a 72-hour period. At 22 C, the pH and PO2 declined over 72 hours while the PCO2 and lactate increased. Hypotonic shock declined to 70 per cent. This differed from the small amounts of CO2 and lactate found at 4 C and the marked accumulation of metabolites and almost complete loss of shock response at 37 C. Aggregation was always better maintained with 4 C storage. The toxic effect of the accumulation of metabolites on the platelets was tested by adding lactate to fresh PC at zero time. This was effective in lowering the initial pH, markedly inhibiting the response to aggregation and decreasing the total accumulation of lactate during storage, but did not produce an inhibition of hypotonic shock response. The effect of accumulation of toxic metabolites was further investigated by using 72-hour plasma and platelets and recombining each of them with fresh preparations. Platelets were tested under degassed conditions to outline the requirements for oxygen and gasious exchange. Surprisingly, there was less accumulation of lactate and CO2 and better hypotonic shock response. These experiments have detected various changes in viability markers in platelets that are stored under actual blood bank conditions and indicate that the accumulation of lactate is not totally responsible for the toxic inhibition of platelet performance that is found upon storage at 22 C.
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PMID:Metabolic changes during platelet storage. 1 76

Rats with complete spinal transections were compressed in helium-oxygen to 120 bars. Tremors and increased EMG activity in limbs rostral as well as caudal to the lesions were observed beginning at 30 bars. Spinal seizures occurred at 95 bars, similar to cortical seizure thresholds of intact rats. Denervated limbs remained flaccid throughout the dives. No rostro-caudal progression of symptoms was evident in normal animals, but fluctuation of symptoms with increasing pressure was frequently observed. These findings are consistent with the hypothesis that the effects of pressure on aggregates of neurons exceed those on isolated components.
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PMID:Spinal cord seizures elicited by high pressures of helium. 8 59

Oxygen tension in the suspension medium and oxygen uptake of the isolated diaphragm of the mouse have been determined simultaneously with systematic variation of shaking frequency and oxygen concentration of the gas phase. Oxygen tension in the suspension medium reaches its final value during the usual equilibration period of 10 minutes and remains constant for the whole measuring period. Each combination of shaking frequency and oxygen concentration of the gas phase results in a reproducible value of oxygen tension in the medium. Equal oxygen tension in the fluid phase can be attained by different combinations of shaking frequency and oxygen concentration of the gas phase. Oxygen uptake at the same oxygen tension of the suspension medium can be very different; it is the higher the higher the shaking rate in the combination. On the other hand the same oxygen consumption of the tissue samples can be observed with highly different oxygen tensions in the medium. It must be concluded from the data in this paper, that the influence of shaking rate per se on the oxygen uptake of isolated tissue can be of the same order as the influence of oxygen tension.
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PMID:Is oxygen consumption of surviving tissues determined by the oxygen tension of the suspension medium? 15 4

Terbutaline, a selective beta2-adrenergic receptor stimulator was given to 10 patients with chronic bronchitis. The effects of the drug were tested by measurements of forced expiratory volume in 1 sec (FEV1), peak expiratory flow rate (PEFR), heart rate, blood pressure and blood gas analysis. The measurements were performed before and 1, 2, 4, 5, and 6 h after oral administration of placebo, 2.5 mg, or 5.0 mg terbutaline. Terbutaline caused a significant dose-related increase in FEV1 and PEFR as compared with placebo. The maximal effects were found at the 4-h measurement and were still present at the measurements performed at 6 h. Heart rate, blood pressure and arterial oxygen tension (PaO2) were not significantly affected. Four patients experienced side effects as tremor and/or heart palpitations. It is concluded that orally administered terbutaline may be an important therapeutical agent in the treatment of chronic bronchitis.
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PMID:Effect of a single graded dose of terbutaline tablets in patients with chronic bronchitis and bronchoconstriction. A double-blind, placebo, cross-over study. 36 41

Most of the previous literature concerning otologic problems in compressed gas environments has emphasized middle ear barotrauma. With recent increases in commercial, military, and sport diving to deeper depths, inner ear disturbances during these exposures have been noted more frequently. Studies of inner ear physiology and pathology during diving indicate that the causes and treatment of these problems differ depending upon the phase and type of diving. Humans exposed to simulated depths of up to 305 meters without barotrauma or decompression sickness develop transient, conductive hearing losses with no audiometric evidence of cochlear dysfunction. Transient vertigo and nystagmus during diving have been noted with caloric stimulation, resulting from the unequal entry of cold water into the external auditory canals, and with asymmetric middle ear pressure equilibration during ascent and descent (alternobaric vertigo). Equilibrium disturbances noted with nitrogen narcosis, oxygen toxicity, hypercarbia, or hypoxia appear primarily related to the effects of these conditions upon the central nervous system and not to specific vestibular end-organ dysfunction. Compression of humans in helium-oxygen at depths greater than 152.4 meters results in transient symptoms of tremor, dizziness, and nausea plus decrements in postural equilibrium and psychomotor performance, the high pressure nervous syndrome. Vestibular function studies during these conditions indicate that these problems are due to central dysfunction and not to vestibular end-organ dysfunction. Persistent inner ear injuries have been noted during several phases of diving: 1) Such injuries during compression (inner ear barotrauma) have been related to round window ruptures occurring with straining, or a Valsalva's maneuver during inadequate middle ear pressure equilibration. Divers who develop cochlear and/or vestibular symptoms during shallow diving in which decompression sickness is unlikely or during compression in deeper diving, should be placed on bed rest with head elevation and avoidance of maneuvers which result in increased cerebrospinal fluid and intralabyrinthine pressure. With no improvement in symptoms after 48 hours, exploratory tympanotomy and repair of a possible labyrinthine window fistula should be considered. Recompression therapy is contraindicated in these cases...
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PMID:Diving injuries to the inner ear. 40 82

Stage 34 (8-day) and 41 (15-day) chick embryos (Gallus gallus; in ovo) were exposed (3 min) to two separate amounts of mechanical (shaking) stress. Oxygen consumption determinations, following a temperature equilibration period (60 min), were made on entire, intact eggs using a Warburg apparatus equipped with 130-ml flasks modified to hold the egg. Shaking at 300 excursions per minute (epm) resulted in depressed O2 consumption by stages 34 and 41. Only stage 34 embryos had markedly depressed O2 consumption values when shaken at 100 epm. When exposed to 300 epm and reincubated for either 1, 2, or 4 hr prior to O2 consumption determinations stage 34 embryos, following an early return to control levels exhibited a marked fall in O2 consumption by 4 h reincubation. The stage 41 embryos, on the other hand, demonstrated a gradual rise to control O2 consumption levels by 4 h reincubation. Oxygen consumption has now been shown for the first time in an embryonic system (at two distinct developmental stages) to be functionally impaired by mechanically induced stress.
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PMID:Oxygen consumption by chick embryos exposed to mechanical (shaking) stress. 42 44

Comparison was made between intentional and postural tremor amplitudes with a 2-to 50-Hz bandwidth in four men rapidly compressed from surface to 13.1, 25.2, and 37.3 ATA in 4 h while breathing helium-oxygen mixtures (Predictive Studies IV, University of Pennsylvania). Excursions with compression rates of 20 and 40 ft/min were then made to 49.4 ATA on exposure days 2 and 3, returning to saturation at 37.3 ATA for 6 additional days. During compression from 25.2 to 37.3 ATA, there were increases in tremor amplitudes for both intentional and postural tremor in the 3-to 7-Hz and 8- to 12-Hz ranges. Both types of tremor showed increases in amplitudes at 49.4 ATA on exposure days 2 and 3. Amplitude changes in postural tremor, which occurred only on the fastest compression to 49.4 ATA, were less evident than those in intentional tremor during the remaining dive profile, and adaptation to pressure exposure could be defined by day 8. Intentional tremors did not show adaptation at pressure.
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PMID:Tremor and somatosensory studies during chamber He-O2 compressions to 13.1, 25.2, 37.3, and 49.4 ATA. 51 89

The ethanol withdrawal syndrome in man and animals is characterized by signs of CNS hyperactivity although a direct measurement of a physiological variable reflecting this CNS hyperactivity has never been performed in untreated man or in animals. We induced ethanol dependence in the rat by means of intragastric intubation with a 20% w/v ethanol solution, thus keeping the animals in a state of continuous severe intoxication for 3--4 days; during the subsequent state of withdrawal characterized by tremor, rigidity, stereotyped movements and general seizures a 25% increase in cerebral oxygen consumption (CMRO2) could be measured; this increase was not due to catecholamines originating from adrenal medulla as adrenomedullectomized animals showed a similar increase in CMRO2 (28%); the withdrawing animals showed a corresponding cerebral blood flow (CBF) increase. The elevated CMRO2 and CBF could be reduced to normal by administration of a beta-adrenergic receptor blocker (propranolol 2 mg/kg i.v.), and hence the increased CMRO2 during ethanol withdrawal could be related to catecholaminergic systems in the brain, e.g. the noradrenergic locus coeruleus system which is anatomically well suited as a general activating system. This interpretation is supported by the earlier neurochemical finding of an increased cerebral noradrenaline turnover during ethanol withdrawal. The exact mechanism underlying the increased cerebral oxygen consumption during ethanol withdrawal and the effect of propranolol on cerebral function during this condition remains to be clarified.
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PMID:Cerebral blood flow and oxygen consumption during ethanol withdrawal in the rat. 57 52

We compared several sets of conditions used to estimate metabolism in rat lung slices. 14CO2 production from [14C]glucose, oxygen consumption, lactate production, and glucose consumption were used as measures of metabolic activity. The calculated results differed when we used 1) different techniques for estimating tissue weight, 2) tissue slices of 0.3-, 0.5-, 0.7-, and 1.0-mm thickness, 3) 95% air or 95% oxygen with 5% CO2 4) a delay after slice preparation and 4 degrees C and room temperature or periods of anoxia before incubation, 5) shaking rates of 60, 90, 120, or 150/min, 6) phosphate or bicarbonate buffers. Conditions of maximal activity were found using 95% O2 with 1.0-mm tissue slices, shaking at 120/min in phosphate buffer without periods of hypoxia or undue delays before incubation. Tissue weight should be obtained without exposure to aqueous solutions or dehydration by contact with cotton gauze or filter paper.
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PMID:Metabolism in rat lung tissue slices: technical factors. 59 83

Several functional tests were performed to compare Hb A, Hb A2, and Hb Lepore Boston, which has a delta-beta crossover in the region of residues 87 to 116. Oxygen equilibrium curves determined by an automatic apparatus in 0.1 M potassium phosphate buffer, pH 7.0, at 20 degrees showed that the p50 was 5.8 mm Hg for Hb Lepore Boston, in contrast to 8.1 and 10.3 mm Hg for Hb A2 and Hb A, respectively. The n values (Hill coefficinets) of Hb Lepore Boston and Hb A2 were slightly smaller than that of Hb A. The effect of 2,3-diphosphoglycerate and inositolhexophosphate on the p50 of Hb Lepore Boston and Hb A2 was less than that on the p50 of Hb A. The molecular stability to mechanical shaking of Hb Lepore Boston and Hb A2 showed that the oxy forms of Hb Lepore Boston and Hb A2 denatured at a rate 3 times faster than that of Hb A. MetHb Lepore Boston was more unstable than MetHb A2 to mechanical shaking. These results indicate that, although the molecular stability of Hb Lepore Boston is more similar to that of Hb A2 than that of Hb A, the oxygen-binding properties of Hb Lepore differ from both Hb A and Hb A2.
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PMID:Comparative studies of Hb Lepore Boston, Hb A2, and Hb A. 61 77


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