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A Hicks

Publications and source records attributed to A Hicks.

At least 19 recordsLinked to original sources
PubMed1995

The expression of syntaxin1B/GR33 mRNA is enhanced in the hippocampal kindling model of epileptogenesis.

Syntaxin, a protein required for the docking of synaptic vesicles, may be involved in the manifestation of synaptic plasticity. The possible involvement of syntaxin in epileptogenesis was investigated by assessing the expression levels of syntaxin1B/GR33 mRNA by in situ hybridization at different stages of hippocampal kindling epileptogenesis and after the induction of generalized seizures. Densitometric analysis of the autoradiograms revealed that the expression was not changed in pyramidal and granular neurons of the hippocampal formation 24 h after the first kindling stimulation. However, the mRNA levels in CA1, CA3, and fascia dentata neurons were bilaterally enhanced after six afterdischarges and remained at this elevated level during the whole period along which afterdischarges were elicited. An immunoassay was unable to reveal a clear significant increase of syntaxin1B/GR33 protein levels in hippocampus homogenates of fully kindled animals. The use of syntaxin1B-specific antibodies is necessary to draw definite conclusions on the changes at the protein level. At long term, 4 weeks after the last kindling-elicited generalized seizure, no significant alterations in transcript levels could be detected. The results suggest that the induction of kindling epileptogenesis is associated with an enhanced expression of syntaxin1B/GR33, but this enhanced expression is not necessary for persistence of kindling-induced synaptic plasticity.

Animals↗
PubMed1994

Trauma.

Explore the source record for details and available documents.

Africa, Eastern↗
PubMed1992

The role of psychological factors in the report of building-related symptoms in sick building syndrome.

Sick building syndrome (SBS) is an increasingly common problem, although continued skepticism exists regarding its validity. Because of this, the attribution of complaints to psychogenic causes or mas hysteria persists. In this study (N = 111), self-report measures of psychopathology (Minnesota Multiphasic Personality Inventory [Hathaway & McKinley, 1983] and SCL-90-R [Derogatis, 1983]) and physical symptom reports failed to discriminate symptomatic from nonsymptomatic workers in an affected building but could more generally differentiate workers in the target building from control subjects. These results suggest that SBS cannot be justifiably attributed to psychological factors alone, although working in a contaminated environment appeared to have deleterious psychological consequences for some workers. Smoking history (in pack/years [packs per day x number of years smoked]) was reliably associated with the development of symptoms in exposed workers. Issues related to the assessment of psychological complaints in SBS are discussed.

Air Pollution, Indoor↗
PubMed1992

Assessment of medical impairment: problems v diabetes traumatic.

The modern concept of diabetes is first considered, i.e a susceptibility to diabetes which can be inherited. The environment may then interact with this susceptibility to determine which persons actually develop clinical complaints and the timing of its onset. The clinical types of established potential and latent diabetics are described together with the proof required for trauma to be accepted as a cause of diabetes rather than exposing a previous diabetic or latent state. Despite an extensive search of the literature and questioning of experts both in Kenya and outside, in the absence of predisposing factors no evidence of trauma being the direct cause of the diabetic syndrome has been found. The one exception may be where there has been definite gross physical injury to the pancreas, but even in this case the evidence is scanty and not very convincing and such cases must be very rare. Trauma may precipitate latent diabetes and its complications and make control more difficult. A percentage assessment is suggested.

Causality↗
PubMed1991

Sick building syndrome.

"Sick building syndrome" (SBS) is one of the more colorful terms describing an increasingly common pattern of symptoms found among workers in modern office buildings. Core symptoms include lethargy, mucous membrane irritation, headache, eye irritation, and dry skin. To prompt a diagnosis of SBS, these otherwise common symptoms must be "excessively" reported and primarily "work-related." The World Health Organization now estimates that 30% of new or remodeled office buildings show signs of SBS, and that between 10% and 30% of the occupants of these buildings are affected by SBS. Despite such figures, SBS remains poorly researched and even more poorly understood. The following review provides the clinician an overview of SBS that will allow a more accurate differential diagnosis and will help to prevent the widespread suffering that can accrue when SBS is not quickly recognized.

Air Conditioning↗
PubMed1991

Medical assessment after injury--problems encountered: IV. Backache.

Most of us have had backache at some time in our lives and it may be very difficult to sort out the complaint of backache after an injury. However a systematic approach together with an assessment of the injured person's reaction to his injuries will generally help. A working structured approach is given together with special tests where exaggeration is suspected. Reference is made to the percentage assessment of backache following injury. Finally it is stressed that "Prophylaxis is the best treatment" especially in an industrial setting.

Back Pain↗
PubMed1989

Increased sodium pump activity following repetitive stimulation of rat soleus muscles.

1. Soleus muscles of anaesthetized rats were stimulated tetanically (4 s at 20 Hz every 5 s for 5 min), following which the resting and action potentials were measured in surface fibres. 2. At the end of the stimulation period, the mean resting potential was found to have increased from a control value of -79.5 +/- 4.8 mV (mean +/- S.D.) to -90.5 +/- 6.3 mV. The hyperpolarization started to decline after 9 min but was still present at 15 min. 3. Associated with the membrane hyperpolarization was an increase in the mean amplitude of the muscle fibre action potential, from 82.2 +/- 10.8 to 96.8 +/- 10.0 mV. 4. Both the hyperpolarization and the enlargement of the muscle fibre action potential were abolished by 1.25 X 10(-4) M-ouabain, cooling the bathing fluid to 19 degrees C or removing K+ from the bathing fluid. 5. The results are explained in terms of an increase in electrogenic sodium pump activity resulting from tetanic stimulation. When the bathing fluid contained 20 mM-K+, the mean resting potential of stimulated fibres was approximately -30 mV greater than that calculated from the Goldman-Hodgkin-Katz equation. 6. The increase in sodium pumping not only acts to restore the concentrations of Na+ and K+ on either side of the muscle fibre membrane, but, through its electrogenic effect, enables fibres to remain excitable during continuous contractile activity.

Action Potentials↗
PubMed1989

M wave potentiation during and after muscle activity.

The M wave (muscle compound action potential) has been shown to enlarge between successive 3-s voluntary contractions of the human thenar and extensor digitorum brevis (EDB) muscles. The changes, which affected both the amplitude and the area of the M wave, were more obvious in the thenar than in the EDB muscles. In the thenar muscles the mean amplitude was already significantly enlarged after the first voluntary contraction and close to the maximal value by the third (mean maximal increase 23.6 +/- 12.6% of control). The increase in mean M wave area was more gradual, reaching a maximum of 29.3 +/- 14.1% at 100 s. After the voluntary thenar contractions ceased, the amplitude of the M wave subsided more rapidly than the area and had regained the control value within 50 s. The magnitude and time course of the increase in EDB M wave area (maximum change 25.9 +/- 15.2%) were similar to those of the thenar muscles; however, the subsequent decline was slower. The amplitude of the EDB M wave showed the least change, and the maximum increase (11.4 +/- 9.6%) occurred early in the postcontraction period. In both muscles the changes in M wave amplitude and area were significantly different from the control values.

Action Potentials↗
PubMed1989

Maximal isokinetic cycle ergometry in patients with coronary artery disease.

We assessed the utility of short-term (30 s) maximal isokinetic cycle ergometry as an additional method of investigating the limitations to exercise in 33 carefully selected patients with documented coronary artery disease. The technique proved safe and reproducible in these patients. In relation to normal standards, performance was better in the maximal isokinetic cycle ergometer test (peak power = 819 +/- 116 W; average power = 532 +/- 72 W; total work = 13.1 +/- 2.1 kJ; 95-101% of predicted) than in the progressive incremental exercise test (VO2 = 1.80 +/- 0.37 l.min-1; power output = 919 +/- 165 kpm.min-1; 70-80% of predicted). Beta blockade did not affect maximal performance during either isokinetic or progressive incremental cycling, although maximal heart rate was significantly lower during both tests in patients on beta blockade. Power output in the progressive exercise was not as strongly related to the indices measured during the 30 s isokinetic test (r = 0.59-0.63) as it was in previous studies of healthy individuals (r = 0.89). The ability to detect individual variations in short-term exercise capacity measured with maximal isokinetic cycle ergometry may have significant potential value 1) as an additional method of determining the limitations to exercise and 2) when executing an exercise prescription in patients with coronary artery disease.

Adrenergic beta-Antagonists↗
PubMed1989

Improvement in maximal isokinetic cycle ergometry with cardiac rehabilitation.

It is unclear whether improvements in short-term (30 s) exercise capacity are associated with the increased aerobic exercise tolerance frequently observed in cardiac patients following training. Carefully selected patients with documented coronary artery disease were randomly allocated either to a control group (N = 10) or to 12 wk of endurance exercise training (N = 12); both progressive incremental cycle ergometer testing (maximal power output and peak VO2) and 30 s maximal isokinetic cycle ergometry (peak power, total work, and fatigue index) were measured on entry into the study and 12 wk later. Initial maximum performance measures in progressive incremental exercise and in maximal short-term isokinetic cycling were similar in both groups. Following the training program, maximum power output measured during progressive incremental exercise increased by 21% (P less than 0.005) and peak VO2 increased by 18% (P less than 0.005) in the exercise group, but they were unchanged in the control group. Isokinetic peak power and total work improved by 14% (P less than 0.001) and 11%, respectively, in the exercise group, whereas there were corresponding reductions of 6 and 8% in the control subjects, with little change in fatigue index in either group. The similar relative increases in isokinetic peak power and peak VO2 suggest that improvement in short-term exercise capacity may be an important contributor to the improvement in aerobic exercise tolerance frequently observed in cardiac patients undergoing an endurance exercise program.

Coronary Disease↗
PubMed1988

Assessment of gallbladder function by ultrasound: implications for dissolution therapy.

Successful treatment of gallstones by oral dissolving agents depends upon a functioning gallbladder. Thirty-one patients were assessed by oral cholecystography and ultrasound before and after a fatty meal. A correlation was demonstrated between radiological opacification and contraction on ultrasound. It is suggested that assessment of gallbladder function may be made by ultrasound methods alone, and an oral cholecystogram is not necessary prior to dissolution therapy.

Adult↗
PubMed1987

The ripple phase of phosphatidylcholines: effect of chain length and cholesterol.

Saturated phosphatidylcholine (PC) bilayers display a rippled surface in the temperature region between the pre- and main transitions. Ripple repeat distance was measured from freeze-fracture electron micrographs. All of the lipids examined (C13PC to C16PC; C14C16PC and equimolar C14PC/C16PC) showed a bimodal distribution of ripple repeat distances with the two dominant values being in the ratio of 1:2. Within this series, chain length was a weak determinant of the actual repeat distance. The introduction of increasing concentrations of cholesterol eliminated the bimodal distribution and led to the appearance of a single distribution of increasing repeat distance and decreasing amplitude. Ripples disappeared above a cholesterol concentration of 15 mol%. These observations are discussed within the framework of a model which links the genesis of the ripples (vertical displacement of lipid molecules) to the trans-gauche isomerization known to occur at the pre-transition.

Chemical Phenomena↗