Morphine versus haloperidol catalepsy in the rat: An electromyographic analysis of postural support mechanisms

Electromyographic recordings from antagonistic flexor and extensor muscles in the forelegs (biceps and triceps) and hind legs (tibialis and gastrocnemius-soleus) of freely moving rats demonstrated that haloperidol (5 and 10 mg/kg, i.p.) and morphine (20 and 40 mg/kg, i.p.) produced contrasting patterns of rigidity. Haloperidol catalepsy was characterized by increases in frequency, intensity, and duration of simultaneous tonic cocontractions in antagonistic flexor and extensor muscles of the limbs. Such synergistic rigidity suggested the release of an adaptive mechanism involved in static support and the maintenance of stable static equilibrium (the positive supporting reaction of Schoen and Magnus), at the expense of locomotor mechanisms. In contrast, morphine produced antagonistic/reciprocal rigidity, which was insensitive to challenges to static equilibrium, and was compatible with locomotion. Contrary to the haloperidol-induced limb postures, which were enhanced supporting reactions, those induced by morphine were “frozen” phases of the step cycle. Haloperidol-induced synergistic rigidity and morphine-induced antagonistic/reciprocal rigidity are discussed as manifestations of contrasting movement subsystems underlying these functionally opposite immobility states. In addition, we present hypotheses concerning supraspinal and spinal mechanisms underlying cataleptic rigidity states, and their relevance as models of parkinsonian rigidity and akinesia.     

The patient's experience of aesthetic regenerative facial surgery: A composite

Data from self-perceptions of 55 female facial aesthetic surgery patients have been combined to show a general composite picture. Personal demographic data, life circumstances, and general attitudes are presented. Patients' motivations for surgery and expectations (both aesthetic result and resulting life changes) have been examined. Patient opinions of how their desires were met are included. The data show the patients' reactions to pre- and postoperative information, self-care instructions, and gernal staff management. Prominent psychological processes in patients presenting for these surgeries are revealed.Independent practice of psychotherapy and psychodiagnosis. Simpson/Lavell Psychology Research in the field of medicine.     

The fitness of categories and vice versa

Two basic propositions are developed as useful in an evolutionary analysis of the origins of complex biobehavioral categories: 1. Such categories derive from the gradual accumulation of a very large number of categoric alternatives, each of which is very small, and 2. Fitness considerations provide valuable insight into the ultimate decision process whereby these micro-categories, and thus eventually, all more complex categories, are achieved.     

Dominant negative selection of vaccinia virus using a thymidine kinase/thymidylate kinase fusion gene and the prodrug azidothymidine

The Escherichia coli thymidine kinase/thymidylate kinase (tk/tmk) fusion gene encodes an enzyme that efficiently converts the prodrug 3'-azido-2',3'-dideoxythymidine (AZT) into its toxic triphosphate derivative, a substance which stops DNA chain elongation. Integration of this marker gene into vaccinia virus that normally is not inhibited by AZT allowed the establishment of a powerful selection procedure for recombinant viruses. In contrast to the conventional vaccinia thymidine kinase (tk) selection that is performed in tk-negative cell lines, AZT selection can be performed in normal (tk-positive) cell lines. The technique is especially useful for the generation of replication-deficient vaccinia viruses and may also be used for gene knock-out studies of essential vaccinia genes.     

Fish macronutrient selection through post-ingestive signals: effect of selective macronutrient deprivation

Recent reports describe teleosts as being able to regulate energy intake by selecting from pure macronutrient sources, although the regulatory mechanisms involved in this selection remain unknown. The aim of the present work was to determine the effect of selective macronutrient deprivation on energy regulation and macronutrient selection, using for this purpose carbohydrate (CH), protein (P), and fat (F) packaged separately into gelatin capsules, a method that prevents the diet chemosensory properties at oropharyngeal level from interfering with macronutrient selection. Twenty-four individually housed sea bass (Dicentrarchus labrax) were subjected to two experiments: (a) two-macronutrient deprivation, and (b) one-macronutrient deprivation. In two-macronutrient deprivation, fish were fed sequentially with P, CH, or F, and in one-macronutrient deprivation, they were fed sequentially with two separately packaged macronutrients (P and CH, CH and F, or P and F). There was a rapid reduction of macronutrient intake in two-macronutrient deprivation, reaching 80% inhibition after 4, 5, and 7 days of P, CH, and F intake, respectively. In one-macronutrient deprivation, the energy intake was significantly reduced during selective F deprivation, but not with P or CH deprivation. Although the fish were being fed with only two macronutrients, the relative proportions of these macronutrients in each selective deprivation phase were the same as the baseline. These results show that in deprivation studies fish need at least F plus one other macronutrient to regulate their energy intake, and that their macronutrient selection is stable even when one is absent. In summary, fish seem to regulate energy and macronutrient selection through post-ingestive mechanisms probably involving chemosensory detection in the gut, and/or post-absorptive mechanisms.     

Toxin-based selection of insulin-producing cells with improved defense properties for islet cell transplantation

Insulin-producing pancreatic beta-cells are known to be extremely susceptible to destruction, primarily by autoimmune mechanisms, infectious agents, and by chemical toxins that cause overt type I diabetes. As development of highly protected insulin-producing cells would be important for successful cell therapy of diabetic patients, gene transfection technique was utilized by several investigators in order to improve the defense properties of transplanted cells. In this article, we summarize other approaches based on a selection strategy that has been developed in our laboratory and by other research groups that engineer pancreatic beta-cells to provide protection against diabetogenic toxins (streptozotocin and alloxan), oxidative stress and cytokines. Selection strategies based on acute repeated or long-term continuous treatment of cell lines with cytotoxic agents have resulted in the selection of highly resistant cell subpopulations. We discuss possible involvement of different expression of cytoprotective genes in the selection of cell subpopulations, which demonstrate a broad spectrum of resistance. Importantly, toxin-based selection did not impair functional activity of the cells as it was shown in vitro. In addition, selected cells preserved their improved metabolic characteristics following encapsulation in alginate and subsequent implantation in diabetic animals. Identifying the mechanisms through which cell defense properties act will help clarify the process responsible for beta-cell regeneration in type I diabetes patients. Such knowledge might be useful in developing strategies focusing on the regeneration of beta-cell resistant populations.     

Feasibility of and delay in obtaining pulse oximetry during neonatal resuscitation

Application of the sensor to newly born infants before connection to a pulse oximeter increases the reliability and speed with which data are displayed. Data are available in most infants within 90 seconds of birth. Oximetry may be useful in guiding interventions during resuscitation.     

Trends in severe bronchopulmonary dysplasia rates between 1994 and 2002

OBJECTIVE: To examine temporal trends in the rates of severe bronchopulmonary dysplasia (BPD) between 1994 and 2002. STUDY DESIGN: In a retrospective cohort study, all infants with a gestational age (GA) <33 weeks in a large managed care organization were identified. Annual rates of BPD (defined as an oxygen requirement at 36 weeks corrected GA), severe BPD (defined as respiratory support at 36 weeks corrected GA), and death before 36 weeks corrected GA were examined. RESULTS: Of the 5115 infants in the study cohort, 603 (12%) had BPD, including 246 (4.9%) who had severe BPD. There were 481 (9.5%) deaths before 36 weeks corrected GA. Although the decline in BPD in this period was not significant, the rates of severe BPD declined from 9.7% in 1994 to 3.7% in 2002. Controlling for gestational age, the odds ratio (95% CI) for annual rate of decline in severe BPD was 0.890 (0.841-0.941). Controlling for gestational age, deaths before 36 weeks corrected GA also declined, with the odds ratio (CI) for the annual decline being 0.944 (0.896-0.996). CONCLUSIONS: In this study population, the odds of having of BPD remained constant after controlling for GA. However, the odds of having severe BPD declined on average 11% per year between 1994 and 2002.     

Sustained pressure—controlled inflation or intermittent mandatory ventilation in preterm infants in the delivery room? A randomized,controlled trial on initial respiratory support via nasopharyngeal tube

AIM: To prove the hypothesis that sustained pressure-controlled inflation compared to intermittent mandatory ventilation for lung recruitment via nasopharyngeal tube after delivery is more effective in reducing the rate of endotracheal intubation and mechanical ventilation in very preterm infants. METHODS: The study was designed as a randomized, controlled trial. The setting was the delivery room and neonatal intensive care unit of a university hospital in Germany. Subjects were 61 infants (25.0-28.9 wk of gestation) with signs of respiratory distress immediately after birth. The infants were randomized in the delivery room to two different respiratory interventions: either to sustained pressure-controlled inflation (15 s) or to intermittent mandatory ventilation (rate 60 min(-1)). This respiratory support was given by a nasopharyngeal tube. The inflation pressure or peak inspiratory pressure was increased stepwise (20-25-30 cm H2O) according to the response of heart rate and oxygenation. RESULTS: The main outcome measure was treatment failure, i.e., endotracheal intubation and mechanical ventilation according to given intubation criteria. Treatment failure occurred in 61% (95% CI, sustained pressure-controlled inflation: 42-78) and 70% (95% CI, intermittent mandatory ventilation: 51-85) (p = 0.59). The rates of mortality (3/61), severe intraventricular haemorrhage (5/61) and chronic lung disease (10/58) were not different between groups. CONCLUSION: Sufficient spontaneous breathing within the first 48 h of life without endotracheal intubation and mechanical ventilation was achieved in about 30% with both methods of initial respiratory support.     

A genomic population genetics analysis of the pathogenic enterocyte effacement island in Escherichia coli: the search for the unit of selection

Comparative genomic analysis is a powerful tool for understanding the history and organization of complete genomes. The mathematical tools of population genetics combined with genomic analysis provide a powerful approach to dissect heterogeneities in genome evolution. This study presents a hierarchical analysis of the enterocyte and effacement island (35 kb), which is found in the enteropathogenic and enterohemorrhagic strains in Escherichia coli and in Citrobacter rodentium. The locus of enterocyte and effacement in E. coli is considered to be a clonal unit inside a clonal organism and is expected to evolve as a single unit. This analysis examines the clonal assumption by determining genetic diversity, GC content, and the substitution rates at the different functional levels of (i) the complete pathogenic island, (ii) the five operons in which the island is organized, and (iii) for each of the individual 41 genes that comprise the locus. We find that there is a conserved region that is composed of genes that belong to the type III secretion system and that may be products of horizontal transfer. A more diverse region is composed of genes for secreted proteins and genes that we infer to be original components of the E. coli genome. This genetic mosaic seems to be differentially affected by selection and mutation. Our results suggest that recombination and selection may be breaking this structure so that different elements are, at best, weakly coupled in their evolution. These observations suggest that the units of selection are not the complete island, but rather, much smaller units that comprise the island.