Initial Recovery Period Research Articles

Protective Apathy, a Hypothesis About the Behavioral Organization and Its Relation to Clinical and Physiologic Status of the Preterm Infant During the Newborn Period

This article describes the behavioral organization and its change in relation to physiologic and clinical variables in a group of infants whose birthweight was less than 1.5 kg and who were experiencing and recovering from acute cardiorespiratory illness. The authors used the Brazelton Premature Sale, which was designed for use with a wide range of gestational ages (27 to 35 weeks). Examinations began 1 week after birth and were obtained serially during the initial recovery period of these infants.

Influence of prostaglandins and ketoprofen on contractile responses of human and pig detrusor and trigone muscles in vitro.

Detrusor and trigone smooth muscle from pig and man were investigated in vitro. The strips were adjusted to a tension of 1 g. During the first hour detrusor strips relaxed and had to be lengthened repeatedly to maintain tension. The tension of strips from the trigone increased spontaneously during this initial period of recovery and accommodation. Detrusor contractions evoked by transmural electric field stimulation, carbachol, histamine and Ca++ were reduced by ketoprofen (an inhibitor of prostaglandin synthesis), while contractions evoked in trigone strips were augmented by ketoprofen. PGE2 10 nM reversed the effect of prostaglandin synthesis antagonism, augmenting the reduced detrusor response and reducing the augmented trigone response. PGF2 alpha augmented evoked contractions in strips from all regions. Activation of endogenous prostaglandin production can not explain the strip behavior during recovery. After recovery, synthesis of the E-type of prostaglandins seem to dominate over the F-type of prostaglandins, since annulment of the E-type of prostaglandins explains best the alterations of evoked contractions following prostaglandin synthesis antagonism.

Loss of microtubules and alteration of glycoprotein migration in organ cultures of mouse intestine exposed to nocodazole or colchicine.

Explants from mouse jejunum were cultured for 3-7 h in the absence (control) or presence of colchicine (100 micrograms/ml) or nocodazole (10 micrograms/ml). In recovery experiments, explants were cultured in fresh medium for an additional period. To label glycoproteins, 3H-fucose was added during the last 3 or 6 h of the initial culture or recovery period. Subcellular fractionation studies revealed that colchicine and nocodazole inhibited migration of labelled glycoproteins to the brush border (P2) by 40-45%. Radioautographic studies of absorptive cells showed that colchicine and nocodazole inhibited labelling of the microvillous border by 67% and 87%, while labelling of the basolateral plasma membrane increased by 114% and 275%. Immunocytochemical studies revealed that both colchicine and nocodazole caused the virtual disappearance of the microtubular network in the absorptive cells. It is possible that some glycoproteins normally destined for the microvillous border are rerouted to the basolateral membrane. The observed loss of microtubules after drug treatment suggests that microtubules may play a role in the intracellular migration of membrane glycoproteins. Additional support for this concept is provided by the fact that in recovery experiments the distribution of label returned to control values after the microtubular network became re-established.

Maintenance of adult rat liver slices in dynamic organ culture.

Adult rat liver slices were maintained for 20 h in a novel organ culture system with minimal loss of viability and function. Potassium and adenosine triphosphate levels were maintained at in vivo levels, following an initial recovery period (2 to 4 h), for up to 20 h. Protein synthesis and secretion were linear for 20 and 16 h, respectively. In addition, the liver slices synthesized glycogen between 4 and 12 h in culture. Finally, the liver slices were hormonally responsive during the 20 h culture period as exemplified by glucagon-stimulated glucose production. This system provides a simple and effective method for the culture and biochemical maintenance of adult rat liver for 20 h with minimal loss of biochemical function.

Behavioral development in the absence of neural activity: effects of chronic immobilization on amphibian embryos

Embryos of Xenopus laevis and Ambystoma mexicanum were continually immobilized from premotile stages of development to stages at which normally reared embryos were swimming well. Immobilization was achieved through exposure to solutions of chloretone, lidocaine, or alpha-bungarotoxin. At a number of stages after recovery from the drugs, spontaneous and stimulated behaviors were extensively quantified. Immobilization of Ambystoma embryos resulted in temporary defects in musculoskeletal development. In contrast, treated Xenopus embryos could not be distinguished from controls by simple visual observation within minutes to hours after removal from the drug solutions. Quantifications of behavior revealed, however, a transient period of 24-48 hr during which treated embryos exhibited consistently reduced measures of stimulated swimming, while showing an increase in frequency of spontaneous movements. Detailed behavioral testing could detect no permanent effects of chronic immobilization in either species after this initial period of recovery. The results are discussed in reference to the classic works of Harrison (1904), Carmichael (1926, 1927), and Matthews and Detwiler (1926).

Movement of Abscisic Acid into the Apoplast in Response to Water Stress in Xanthium strumarium L.

The effect of water stress on the redistribution of abcisic acid (ABA) in mature leaves of Xanthium strumarium L. was investigated using a pressure dehydration technique. In both turgid and stressed leaves, the ABA in the xylem exudate, the ;apoplastic' ABA, increased before ;bulk leaf' stress-induced ABA accumulation began. In the initially turgid leaves, the ABA level remained constant in both the apoplast and the leaf as a whole until wilting symptoms appeared. Following turgor loss, sufficient quantities of ABA moved into the apoplast to stimulate stomatal closure. Thus, the initial increase of apoplastic ABA may be relevant to the rapid stomatal closure seen in stressed leaves before their bulk leaf ABA levels rise.Following recovery from water stress, elevated levels of ABA remained in the apoplast after the bulk leaf contents had returned to their prestress values. This apoplastic ABA may retard stomatal reopening during the initial recovery period.

Cicer Milkvetch and Alfalfa as Influenced by Two Cutting Schedules1

AbstractCicer milkvetch (Astragalus cicer L.) is a promising forage legume, but little is known about its response to cutting. A 2‐year study was conducted at Fort Collins, CO, on a Nunn clay loam (fine, montmorillonitic, mesic Aridic Argiustoll) soil to compare yield, quality, and trends in carbohydrate reserves of cicer milkvetch and alfalfa (Medicago sativa L.) in response to annual three‐ and four‐cut clipping treatments. Quality was evaluated by determining concentrations of crude protein (CP) and cell wall constituents (CWC) in herbage from each harvest. Seasonal dry matter yields of alfalfa were similar under both clipping treatments during each year. Yields of cicer milkvetch were reduced under the more frequent cutting schedule in 1979, but not in 1980. During 1979, quality differences between the clipping treatments were apparent for alfalfa but not for cicer milkvetch. Improved quality, as measured by increased CP and decreased CWC concentrations, was observed in herbage from both species under the more frequent clipping treatment in 1980. Herbage CP concentration was simiilar under comparable clipping treatments during both years, however, the CWC concentration of cicer milkvetch was consistently lower than that of alfalfa. Cyclic trends in carbohydrate reserves were observed in alfalfa under both clipping treatments in 1980, but only under the three‐cut treatment in 1979. Carbohydrate reserve trends in cicer milkvetch roots and rhizomes were less cyclic than in alfalfa and similar under both cutting schedules each year. Carbohydrate reserve concentrations in all forage entries were similar at the end of the 1980 growing season regardless of clipping treatment. Following cutting, carbohydrate reserves in alfalfa were readily utilized during the initial period of recovery. Carbohydrate reserves in cicer milkvetch appeared to be actively involved in regrowth processes only when little, or no, residual leaf area remained after cutting.

A conceptual framework and treatment strategy for the alcoholic urge to drink utilizing hypnosis.

The present paper proposes a theoretical framework and a treatment strategy for dealing with the urges to drink that alcoholics experience during recovery. Two models are proposed: the Defense Model and the Conditioning Model. Each model covers a specific period of time during recovery in which the urges to drink occur. The Defense Model describes the urges that result in the initial recovery period, while the Conditioning Model is invoked to explain urges that materialize in the later phases of recovery. Next, a treatment strategy is delineated that incorporates these models and employs the use of hypnosis. The treatment strategy is divided into three phases, with the first and second phases dealing with the alcoholic's unconscious and the third phase being directed at the alcoholic's conscious.

Effect of sleep deprivation on sleep and EEG power spectra in the rat

EEG power spectra of the rat were computed for consecutive 4-s epochs of the daily light period and matched with the scores of the vigilance states. Sleep was characterized by a progressive decline of low frequency spectral values (i.e. slow wave activity) in non-rapid eye movement (non-REM) sleep, and a progressive increase in the amount of REM sleep. During recovery from 24-h total sleep deprivation (TSD) the following changes were observed: an increase of slow wave activity in non REM sleep with a persisting declining trend; an enhancement of theta activity (7.25-10.0 Hz) both in REM sleep and waking; a decrease of non-REM sleep and an increase of REM sleep. In addition, a slow wave EEG pattern prevailed in the awake and behaving animal during the initial recovery period. In selective sleep deprivation paradigms, either REM sleep or slow wave activity in non-REM sleep was prevented during a 2-h period following upon 24-h TSD. During both procedures, non-REM sleep spectra in the lowest frequency band showed no increase. There was no evidence for a further enhancement of slow wave activity after its selective deprivation. The results indicate that: (1) slow wave activity in non-REM sleep and theta activity in REM sleep may reflect sleep intensity; and (2) REM sleep and active waking, the two states with dominant theta activity, may be functionally related.

Effects of glucagon on biosynthesis of the mitochondrial enzyme, carbamoyl-phosphate synthase I, in primary hepatocytes and Morris hepatoma 5123D

When freshly-dispersed rat hepatocytes are maintained in primary monolayer cultures, they quickly lose their capacity to synthesize the urea cycle enzyme, carbamoyl-phosphate synthase. The ability to synthesize many other proteins, e.g., serum proteins including albumin, is retained. After an initial recovery period following cell isolation (24–48 h), glucagon is able to restore the ability of cultured hepatocytes to make carbamoyl-phosphate synthase. mRNA encoding the enzyme is about 4-times higher in hepatocytes maintained for 48 h in the presence of glucagon compared to hepatocytes without the hormone, as judged by in vitro translational assays. The level of carbamoyl-phosphate synthase activity expressed in transformed hepatocytes is unique to each hepatoma. Here we show that Morris hepatoma 5123D has retained such expression, and actively synthesizes the enzyme when 5123D cells are placed in monolayer cultures. Unlike normal hepatocytes, however, synthesis continues uninterrupted at a high level whether or not glucagon is present. 5123D has higher levels of translatable carbamoyl-phosphate synthase mRNA than normal liver.

Intestinal Absorption of Electrolytes in Marasmic Children with Diarrheal Dehydration

A study was performed to estimate intestinal absorption of electrolytes, administered in cow's milk, during recovery from diarrheal dehydration. Seven marasmic children with diarrheal dehydration and estimated acute losses of over 10% of body weight were studied. Metabolic balance collections were performed for at least 6 days, starting from admission. After recovery from the acute episode all children had weight and height under the third percentile for Brazilian standards and were free of edema. Recovery was uneventful for all children, with improvement of diarrhea on the third day. During the first day, no milk was administered, one-third strength cow's milk was started on the second day and, depending on tolerance, increased in amount and strength to whole cow's milk by the end of the sixth day. Significant correlations between amounts ingested and absorbed were observed for all electrolytes from the fourth day onwards. The average percentage of absorption of Na, K, and C1 increased from the third day onwards, with significant differences of the second day in relation to the fifth and sixth days. The average percentage of absorption of Ca, Mg, and P was almost constant from the second day. This study shows that in marasmic children with diarrheal dehydration absorption of electrolytes in cow's milk can be predictable only when diarrhea improves. During the initial recovery period, no correlation was found between amounts administered and absorbed.

Diabetes and the survival and recovery of the anoxic myocardium

In studies with the isolated perfused working hearts from rats with experimentally induced diabetes, the ability of the hearts to survive during, and recovery from, 30 min of anoxia has been studied. In contrast with hearts obtained from normal rats, which gave good and sustained recoveries, the hearts from diabetic animals after an initial period of recovery (approx. 2 min), exhibited cardiac failure for periods of up to 4 min. After this period the hearts entered a second phase of recovery but did not recover to the same extent as the hearts from normal animals. Hearts of diabetic animals therefore appear to be more vulnerable to anoxic damage than do those from normal rats. Using metabolic inhibitors the biochemical basis of this transient post-anoxic failure in diabetic hearts was investigated. It was discovered that the immediate post-anoxic recovery of the hearts was supported in part by endogenous supplies of pre-formed high energy phosphates and in part from energy derived from the glycolysis of endogenous glycogen. During the initial recovery period of approx. 2 min there was little dependence upon the oxidative metabolism of either endogenous or exogenous substrates. In normal hearts the role of major energy provider was rapidly assumed by oxidative processes utilizing exogenous substrate. In the insulin deficient diabetic hearts the impaired transport of glucose into the cell and consequent energy shortage led to the transient cardiac failure and accounted for the delayed secondary recovery. This condition could be completely overcome either by the provision of exogenous insulin or by the provision of substrates such as pyruvate, acetate, citrate or hydroxybutyrate, whose efficient utilization was not impaired by an insulin deficiency. The relevance of these findings in the diabetic rat heart is discussed in relation to the known insulin deficiency occurring in the human during heart failure and the proposed importance of glucose metabolism in the support of the failing myocardium. In addition, these findings are considered in relation to the possible role of insulin both in the genesis and the treatment of heart failure with particular reference to heart failure in humans with diabetes mellitus.

Effects of noradrenaline on potassium reflux, membrane potential and electrolyte levels in tissue slices prepared from guinea-pig liver.

1. Some effects of noradrenaline on potassium efflux, electrolyte levels, membrane potential and current distribution in guinea-pig liver slices have been examined.2. The slices (thickness ca. 300 mum) were prepared from the median lobe of the liver and incubated at 38 degrees C in a mammalian Ringer fluid containing 2 mM pyruvate. After an initial recovery period, the ionic composition of the tissue remained stable for several hours.3. The steady-state contents of sodium, potassium and chloride were 296, 266 and 272 m-equiv/kg dry tissue respectively. The inulin space was 29 ml./100 g wet tissue.4. Most if not all of the tissue potassium was exchangeable. The rate constant for (42)K efflux was 0.019 min(-1).5. Noradrenaline (1 muM) markedly increased the efflux of (42)K and within 2 min caused tissue potassium to fall by 8%. At the same time the sodium content rose.6. Traverses of the slices with micro-electrodes showed many negative-going deflexions of 30-40 mV in amplitude. The evidence suggests that these correspond to the membrane potentials of the parenchymal cells.7. Noradrenaline (1 muM) caused a reversible hyperpolarization of about 10 mV. The response became larger on replacing external chloride by isethionate or methylsulphate, but was little affected by a reduction in external potassium.8. After slices had been bathed in potassium and chloride-free solutions for several min, restoration of external potassium caused the membrane potential to increase by up to 10 mV. This hyperpolarization, but not that caused by noradrenaline, was abolished by ouabain.9. Noradrenaline reduced the amplitude and quickened the time course of electrotonic potentials set up by current pulses from another microelectrode, suggesting that the membrane conductance had risen.10. Although certain mechanisms based on electrogenic active transport processes with unusual properties have not been excluded, the present findings are more simply explained by supposing that noradrenaline increases the potassium permeability of the parenchymal cell membrane.

Colonna Capsular Arthroplasty

A follow-up study of thirty-six patients with forty dislocated hips, treated by Colonna's capsular arthroplasty at The Hospital for Special Surgery between 1936 and 1964, led to the following conclusions: 1. Regardless of the cause of the dislocation, a majority of well established dislocations of the hip in which the two joint surfaces are markedly disproportionate can be successfully reduced and stable functional joints can be produced by Colonna arthroplasty, provided that the femoral head is spherical and can be pulled down opposite the true acetabulum. 2. Traction, continued for sufficient time to pull the femoral head down to the level of the true acetabulum, is an essential preliminary step. In some instances when the arthroplasty is performed, the femoral head can be mobilized sufficiently by soft-tissue release without preliminary traction. However, preliminary traction should always be employed unless contraindicated. Previous surgical treatment or infection with subsequent scarring may make traction ineffective. 3. Other technical factors (the construction of an adequately deep acetabulum at the proper level or close to it, derotational femoral osteotomy to correct excessive anteversion when present, postoperative immobilization in a plaster spica for not longer than three to six weeks, and early resumption of movement while delaying weight-bearing) are also important in gaining good results. 4. After the initial recovery period of from two to three years, the functional qualities of adequately reconstructed hips remain stable, at least for the years spanned by this study. 5. The indications for capsular arthroplasty as outlined by Colonna can be extended to include bilateral congenital dislocation of the hip; paralytic dislocation secondary to lower motor neuron or root lesions; and certain healed septic dislocations. The age restriction (three to eight years of age) proposed by Colonna can be expanded, partticularly for paralytic dislocation. 6. The subluxated hip fixed in a false acetabulum is the most difficult type to treat by this method and probably constitutes a contraindication to its use.

Effect of glutamine starvation on the ultrastructural organization of Chang's cultured cells

Ultrastructural changes in exponentially growing Chang liver cells in response to glutamine starvation for 24 h and successive recovery stages after glutamine restoration were studied. Alterations due to starvation were reduction in the number of free ribosomes, polyribosomes, rough endoplasmic reticular profiles and mitochondria; the Golgi complex and multivesicular bodies disintegrated and disappeared; nuclear chromatin was less dense and cytoplasmic fibrils increased in the cells. Glutamine restoration produced reversal of changes in the affected subcellular constituents. A sudden rise in synthetic activity in the initial recovery period was indicated by an increase in the polyribosomes and free ribosomes which preferentially crowded the circumnuclear region. This region expanded with the recovery time. Extensive Golgi apparatus, rough endoplasmic reticulum, and proliferating mitochondria with dense granules in the matrix appeared. Multivesicular bodies reappeared in cells recovered completely at 24 h. Asbestos crystals were observed in dense bodies in all the stages. The findings are discussed in relation to the possible effect of glutamine on subcellular structure and function.

Oxygen consumption by the isolated smooth muscle of guinea‐pig taenia coli

1. An apparatus is described for simultaneous measurement of oxygen consumption and electrical and mechanical activity of isolated smooth muscle preparations.2. The mean oxygen uptake by the isolated taenia coli of the guinea-pig was 10-20 mul./g/min.3. In spontaneously active preparations, adrenaline (10(-8)-10(-7) g/ml.) caused, with the inhibition of electrical and mechanical activity, a reduction in oxygen uptake.4. After prolonged exposure to substrate free solution spontaneous activity ceased periodically. Adrenaline, when applied during a silent period, had no detectable effect on resting oxygen consumption, while readmission of substrate, either glucose or beta-hydroxybutyrate, increased oxygen uptake.5. Adrenaline did not modify the increased oxygen uptake during the initial recovery period when it was given simultaneously with the substrate. However, adrenaline shortened the time interval which elapsed from the addition of substrate until spontaneous activity was resumed, indicating an acceleration of the recovery process.