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Biomedical subjects

J Patrick

Publications and source records attributed to J Patrick.

At least 217 records · Page 12Linked to original sources
PubMed1979

Human fetal breathing activity during electively induced labor at term.

Human fetal breathing movements were measured during the first stage of electively induced labor in 20 healthy term pregnancies. Fetuses made breathing movements 25.6% of the time during a 1 hour control period and breathing decreased significantly to 8.3% during latent-phase labor and further decreased to 0.8% during active labor (P less than 0.001). Patterns of increased fetal breathing activity accompanied by increased gross fetal body movements and increased fetal heart rate variability for periods of 20 to 60 minutes out of every 1.0 to 1.5 hours were observed, and the intermittent patterns of increased body movement and heart rate variability continued throughout the first stage of labor despite the decrease in fetal breathing activity during latent- and active-phase labor. It will be important to account for rest activity patterns when interpreting variability of heart rate during labor. The absence of fetal breathing activity during electively induced labor at term is not a clinical indicator of fetal ill health.

Anesthesia, Epidural↗
PubMed1979

Staff reactions to the closing of a community mental health center.

Many community mental health centers face seriuos financial problems as they near the end of the federal funding period. The author describes the developments surrounding an extended financial crisis at an inner-city mental health center that eventually was forced to close. Using a crisis theory framework, she examines staff reactions to the crisis and proposes an intervention model in which a consultant is employed to help staff identify and avoid maladaptive coping behavior.

Adaptation, Psychological↗
PubMed1978

Patterns of human fetal breathing activity at 34 to 35 weeks' gestational age.

Continuous measurements of human fetal breathing movements at 34 to 35 weeks' gestational age were made with an ultrasonic real-time scanner for periods of 24 hours in 11 women. A significant increase occurred in fetal breathing activity during the second and third hour following meals and this pattern apparently followed an increase in maternal plasma glucose concentration. There was a prolonged significant increase in fetal breathing activity between 0100 and 0700 hours. Increases in human fetal breathing activity accompanied by increased gross fetal body movements occurred for periods of 20 to 60 minutes out of every 1.0 to 1.5 hours of observation time. It was concluded that the percentage of time spent breathing by normal fetuses was related to time of day and maternal meals. The alternating changes of fetal activity and inactivity observed may represent biologic changes of sleep state in the human fetus in utero at 34 to 35 weeks' gestational age. It will be important to account for these three patterns of fetal breathing activity in clinical studies which examine the usefulness of fetal breathing movements in assessing fetal health.

Abdominal Muscles↗
PubMed1978

Effects of human maternal venous plasma glucose concentrations on fetal breathing movements.

Human fetal breathing movements were studied following the maternal ingestion of either a 50 Gm. oral glucose load or an equal volume of water in 22 healthy women with uncomplicated pregnancies at 32 to 34 weeks' gestation. The percentage of time spent breathing in fetuses of glucose-treated mothers increased from 23.2 +/- 2.2 per cent during the control period to a maximum of 58.9 +/- 5.2 per cent at 105 minutes following the oral glucose load (p less than 0.01) which was one hour following the peak maternal plasma glucose concentration. No similar increase in maternal glucose concentrations or percentage time spent breathing occurred in patients receiving water. Fetal breathing movements were observed in 97 per cent of the 15 minute periods during the second and third hour after maternal ingestion of a 50 Gm. oral glucose load. It was concluded that maternal carbohydrate intake two hours prior to fetal breathing observations should be documented to permit adequate interpretation of fetal breathing activity.

Administration, Oral↗
PubMed1978

Human fetal breathing movements and gross fetal body movements at weeks 34 to 35 of gestation.

Human fetal breathing movements in utero at 34 to 35 weeks' gestational age were measured using a real-time ultrasonic scanner. Fetal breathing movements were episodic and occurred 31.8 per cent of the time. Aanalysis of continuous recordings in 10 fetuses from 09:00 to 17:00 hours demonstrated that the percentage of time spent breathing per hour was greater in the afternoon than in the morning. The number of gross fetal body movements was also greater in the afternoon than in the morning. The percentage of time spent breathing was significantly greater during the hour following the noon meal than during the hour preceding the noon meal. It was concluded that real-time ultrasonic scanning permits identification of fetal breathing movements and that between 09:00 and 17:00 hours the character of these movements is related to the time of the day and to the ingestion of food by the mother.

Adolescent↗
PubMed1978

Effect of zinc on leucocyte sodium transport in vitro.

1. In a preparation of human leucocytes maintained in tissue culture fluid, increasing the extracellular zinc concentration leads to a significant increase in both ouabain-sensitive sodium efflux and in sodium influx. 2. Cell water and sodium content do not alter significantly with increasing extracellular zinc concentration. 3. A small increase in the ouabain-insensitive sodium efflux can be demonstrated when the external zinc concentration is raised from 0.75 mumol/l to 90 mumol/l.

Biological Transport, Active↗
PubMed1978

Total body water in malnutrition: the possible role of energy intake.

1. Total body water (TBW) was measured using tritiated water in sixty-five children. The measurements were distributed throughout rehabilitation in order to define the effect of changing energy intakes. 2. Oedematous children had a high TBW which decreased to the normal range during loss of oedema providing they were not receiving more than maintenance amounts of energy during this period. 3. Marasmic children who had not received greater than maintenance amounts of energy had a normal TBW. 4. Treatment with a high-energy diet was associated with an initial increase in TBW. 5. The possible mechanisms for this phenomenon are discussed.

Body Water↗
PubMed1978

Biology of cultured nerve and muscle.

Cells from the nervous system can be grown in culture and exhibit many of the biophysical, biochemical, and morphological properties found in vivo. They can be induced to differentiate in culture and perform some of the interactions that occur in the nervous system, including synaptogenesis. A number of important questions relating to nervous system development and function have been approached in culture in ways that cannot be done in vivo. The use of clonal cell lines should lead to rapid progress in the analysis of the nervous system at the chemical level.

Acetylcholine↗
PubMed1978

The relationship between intracellular and extracellular potassium in normal and malnourished subjects as studied in leukocytes.

Leukocyte potassium has been measured in normal subjects and in malnourished children with and without edema both on admission and during recovery. In nonedematous malnourished children the potassium content was low (328 mmol/kg dry solids) and took 2-3 weeks of rehabilitation to return to normal (374 mmol/kg dry solids). Leukocytes from edematous children had normal intracellular potassium values. However, 5 days on a maintenance diet reduced the intracellular potassium in the children with kwashiorkor to a value similar to that found in marasmus. Plasma potassium was significantly lower in kwashiorkor (3.43) than in marasmus (4.74), The relationship between external potassium and internal potassium in normal leukocytes was measured (Fig. 1) and the values found in severe malnutrition compared with normal. It was found that in nonedematous malnutrition intracellular potassium was low compared to the predicted value, whereas in kwashiorkor, although the mean values were normal, no relationship between external potassium and intracellular potassium could be domonstrated. It is concluded that in the leukocyte malnutrition alters either the passive permeability of the membrane to potassium or the active transport of potassium, or both.

Biological Transport↗
PubMed1978

Interrelations between the physiology of sodium, potassium and water, and nutrition.

The relationships between altered nutrition and body composition of sodium, potassium and water are reviewed. The physiological mechanisms involved in cellular homeostasis of sodium and potassium are also discussed with particular reference to energy costs. Alterations in mineral metabolism in protein energy malnutrition, oedema, potassium adaptation, fasting and hypertension are described.

Adaptation, Physiological↗
PubMed1977

alpha-Bungarotoxin binding and cholinergic receptor function on a rat sympathetic nerve line.

A clonal rat sympathetic nerve cell line, PC12, binds iodinated alpha-bungarotoxin. The binding is saturable and is inhibited by a variety of cholinergic agonists and antagonists. The pseudo-first order rate constant for binding is 2.1 x 10(5) M-1 S-1 at 22 degrees. In contrast to the alpha-bungarotoxin binding reaction found with muscle, the binding to PC12 is reversible with a first order rate constant of 4.9 x 10(-5) S-1 at 37 degrees. Toxin binds to an integral membrane component which sediments in sucrose gradients containing Triton X-100 with an apparent sedimentation coefficient of 10.5 S. The nicotinic acetylcholine receptor of PC12 was assayed by determining the agonist-induced increase in permeability to sodium ions. Using this assay, we determined the apparent binding constants for a variety of cholinergic ligands and found no correlation between their ability to affect cholinergic function and to inhibit binding of alpha-bungarotoxin. Therefore, the site at which cholinergic ligands affect receptor function is different than the site at which cholinergic ligands inhibit toxin binding.

Binding, Competitive↗