Adoptive Identity: How Contexts Within and Beyond the Family Shape Developmental Pathways*

The focus of this paper is adoptive identity, the sense of who one is as an adopted person. The paper first considers how identity has been shaped by recent social changes, and then explores the meaning of adoptive identity and its developmental course. Three contexts of development are examined: intrapsychic, the family environment, and contexts beyond the family, including relationships with friends, connection to community, and culture. Implications for professionals who work with adopted persons and for needed research are also discussed.     

Effect of theophylline on membrane potential and contractile force in hamster diaphragm muscle in vitro.

Theophylline enhances the force of diaphragmatic contraction and delays fatigue. The mechanism is not known, but recent evidence suggests it may act at the cell membrane. To test this hypothesis, we studied the effect of theophylline on resting membrane potential and tension in hamster diaphragm cells. Muscle strips were obtained from five adult hamsters and placed in Krebs solution, aerated with 95% O2, 5% CO2. Resting membrane potential was measured using 3-M KCl-filled glass microelectrodes; 15-22 fibers in each strip were sampled. Force frequency curves (twitch to 100 Hz) were obtained. The muscle bath was then changed to one containing 100 mg/liter (0.55) theophylline. Resting membrane potential was -76 +/- 3 mV (mean +/- S.D.) in Krebs solution and increased to -85 +/- 3 mV (P less than 0.01) with added theophylline. Tension increased from 5% (at 100 Hz) to 20% (at 10 Hz) with theophylline. Hyperpolarization indicates an increase in intracellular to extracellular potassium concentration. Net potassium outflow occurs with each contraction, causing the cell membrane to become depolarized with repeated contractions, ultimately leading to fatigue. The hyperpolarization of the skeletal muscle cell membrane observed with theophylline may play an important role in prolonging time to fatigue.     

Effects of the mycotoxin destruxin A on Locusta migratoria visceral muscles

Destruxins, a family of cyclic peptides, are produced by various species of entomopathogenic fungi. These peptides have been shown to influence calcium-dependent processes in insect cell lines and tissues, such as skeletal muscles. To better understand the mechanism of action of these peptide toxins on insect muscular tissues, we have evaluated the effects of destruxin A on the contractions of oviducts and hindgut of Locusta migratoria. In oviducts, destruxin A increased the frequency of spontaneous contractions and induced a dose-dependent tonic contraction; the EC₅₀ for lower lateral and upper lateral oviducts was 0.7 μM and 8.7 μM, respectively. In hindgut, destruxin A also caused an increase in the frequency of spontaneous contractions; the EC₅₀ was 3.2 μM. The action of destruxin A was abolished in Ca²⁺-free saline or when the Ca²⁺ channel blocker CoCl₂ was added to the incubation saline. Likewise, the presence of 50 μM nifedipine or 100 μM verapamil in the medium reduced the magnitude of destruxin A′s effect, particularly in hindgut. The depolarization of muscle membranes by 100 mM K⁺ saline prevented the action of destruxin A. Preincubation of lower lateral oviducts in the intracellular Ca²⁺ antagonist TMB-8 did not have any effect on destruxin A action; however, preincubation in the calmodulin inhibitor trifluoperazine greatly reduced the effect of destruxin A. Taken together, these results show that destruxin A has an excitatory effect on contractions of insect visceral muscles of L. migratoria. Destruxin A-induced contractions appear to be dependent on extracellular, but not on intracellularly-released Ca²⁺, which suggest that this peptide toxin might be acting on insect visceral muscle by facilitating an influx of extracellular Ca²⁺.     

Über Klimakterische Gesichtsbehaarung

Ohne Zusammenfassung     

Research workshop to research work: initial steps in establishing health research systems on Malaita,Solomon Islands

Introduction  

Atoifi Adventist Hospital is a 90 bed general hospital in East Kwaio, Malaita, Solomon Islands providing services to the population of subsistence villagers of the region. Health professionals at the hospital and attached College of Nursing have considerable human capacity and willingness to undertake health research. However they are constrained by limited research experience, training opportunities, research systems, physical infrastructure and access to resources. This brief commentary describes an 'Introduction to Health Research' workshop delivered at Atoifi Adventist Hospital in September 2009 and efforts to move from 'research workshop' to 'research work'.     

Die indirekten Schaftbrüche an den Extremitäten

Ohne Zusammenfassung Mit 2 Abbildungen.