SCAR DISABILITIES OF WOUNDED HANDS

1. The importance of early relief of scar disabilities of the hand is emphasized–that is, before joint changes are established. 2. The part of early wound healing, early function and correct use of physiotherapy in preventing and minimizing scar disabilities of the hand is stated. 3. The “hand grenade” type of injury is described and used as a basis to describe the principles of an effective scar excision and replacement by a full-thickness skin graft. 4. A “through” type of hand wound is described in so far as scar effects are concerned. The principles of effective treatment by (a) scar excision and rearrangement for small scars and (b) scar excision and direct flap replacement for large scars are set out. 5. Other types of scar disability and their treatment are indicated– namely, web scars, adherent scars of fingers and burn scars. 6. A plea is made for the full application of plastic surgery to obtain better results from all hand wounds.     

Perceptions and attitudes of Canadian orthodontists regarding digital and electronic technology.

INTRODUCTION: To plan for future acceptance and implementation of computer-related technology, it is necessary to understand orthodontists' current perceptions and attitudes toward emerging technologies. METHODS: An anonymous, self-administered, mail-out survey of Canadian orthodontists was conducted. The response rate was 45.6% (304/667). RESULTS: Most orthodontists indicated that computer technology could improve current practice efficiency and quality of patient care. Only 15% reported that digital models are quite or very useful; 73.6%, 69.1%, 55%, and 37.4% agreed or strongly agreed with using digital and electronic technology to consult with other dental specialists, other orthodontists, general dentists, and the public, respectively. Cost of the technology was reported as a significant or insurmountable obstacle by 54% of the respondents. Interprovincial legislation, unclear consultation remuneration guidelines, and lack of comfort with the technology were not perceived as significant obstacles. Only 36% reported security or privacy issues as a significant or insurmountable obstacle. CONCLUSIONS: Canadian orthodontists seem to view digital and electronic technology as useful and capable of improving their offices' efficiency and production. Although they are sensitive to some potential obstacles, they are willing to overcome these and incorporate the technology into their practices.     

PIP2 hydrolysis underlies agonist-induced inhibition and regulates voltage gating of two-pore domain K+ channels

Two-pore (2-P) domain potassium channels are implicated in the control of the resting membrane potential, hormonal secretion, and the amplitude, frequency and duration of the action potential. These channels are strongly regulated by hormones and neurotransmitters. Little is known, however, about the mechanism underlying their regulation. Here we show that phosphatidylinositol 4,5-bisphosphate (PIP₂) gating underlies several aspects of 2-P channel regulation. Our results demonstrate that all four 2-P channels tested, TASK1, TASK3, TREK1 and TRAAK are activated by PIP₂. We show that mechanical stimulation may promote PIP₂ activation of TRAAK channels. For TREK1, TASK1 and TASK3 channels, PIP₂ hydrolysis underlies inhibition by several agonists. The kinetics of inhibition by the PIP₂ scavenger polylysine, and the inhibition by the phosphatidylinositol 4-kinase inhibitor wortmannin correlated with the level of agonist-induced inhibition. This finding suggests that the strength of channel PIP₂ interactions determines the extent of PLC-induced inhibition. Finally, we show that PIP₂ hydrolysis modulates voltage dependence of TREK1 channels and the unrelated voltage-dependent KCNQ1 channels. Our results suggest that PIP₂ is a common gating molecule for K⁺ channel families despite their distinct structures and physiological properties.     

Lectin-induced increase in clonogenic growth of haematopoietic progenitor cells

Abstract: The galactoside-specific plant lectin, Viscum album agglutinin (VAA-I) increases cellular parameters of natural host defence. It also binds to a variety of haematopoietic cells, including progenitors. We investigated whether VAA-I has a stimulatory effect on haematopoietic progenitor cells. Peripheral blood progenitor cells from 7 healthy volunteers were cultured in a colony assay with VAA-I plus erythropoietin (EPO) and stem cell factor (SCF). At 50 pg/ml VAA-I induced a significant increase in the cytokine-dependent clonogenic growth (52% in median, p<0.05). In another set of experiments purified CD34+ cells were isolated from the bone marrow aspirate of 4 patients with non-metastatic breast cancer using fluorescence-activated cell sorting. Binding to CD34+ cells was demonstrated by using directly fluorescence-conjugated VAA-I. Co-incubation with d -galactose significantly abrogated this effect. CD34+ cells were cultured in the presence of EPO, SCF, interleukin-3, granulocyte/monocyte colony-stimulating factor and granulocyte colony-stimulating factor. VAA-I alone had no measurable effect on the clonogenic growth of the isolated cells. However, at concentrations of 100 and 250 pg/ml VAA-I increased the cytokine-dependent proliferation and differentiation of CD34+ cells by a median of 75 and 85%, respectively. The results show that VAA-I binds to haematopoietic progenitor cells and has a co-stimulatory effect on their proliferation.     

Multicenter retrospective development and validation of a clinical prediction rule for nosocomial invasive candidiasis in the intensive care setting

The study presented here was performed in order to create a rule that identifies subjects at high risk for invasive candidiasis in the intensive care setting. Retrospective review and statistical modelling were carried out on 2,890 patients who stayed at least 4 days in nine hospitals in the USA and Brazil; the overall incidence of invasive candidiasis in this group was 3% (88 cases). The best performing rule was as follows: Any systemic antibiotic (days 1–3) OR presence of a central venous catheter (days 1–3) AND at least TWO of the following—total parenteral nutrition (days 1–3), any dialysis (days 1–3), any major surgery (days −7–0), pancreatitis (days −7–0), any use of steroids (days −7–3), or use of other immunosuppressive agents (days −7–0). The rate of invasive candidiasis among patients meeting the rule was 9.9%, capturing 34% of cases in the units, with the following performance: relative risk 4.36, sensitivity 0.34, specificity 0.90, positive predictive value 0.01, and negative predictive value 0.97. The rule may identify patients at high risk of invasive candidiasis. Results of this project were partially presented at Focus on Fungal Infections 14, New Orleans, LA, USA, 2004. Abstract no. 51.     

Cellular Distribution of G Protein Goa in Pituitary Lactotrophs: Effects of Dopamine

Membrane-bound GTP-binding (G) proteins mediate signal transduction in a variety of cell systems. The exact mechanisms of G proteins action are still under investigation but they appear to involve effectors located in the plasma membrane as well as in other parts of the cell. With this study, we investigated the cellular and ultrastructural localization of G protein subunits, and particularly of Goa, in normal rat anterior pituitaries and in estrone-induced rat adenomatous lactotrophs. We also evaluated the effects of Goα cellular redistribution in rat adenomatous lactotrophs following short-term exposure to dopamine (DA). Using the Protein A-gold (PAG) methodology, Goα was found to be present in the cysternae of the endoplasmic reticulum of normal pituitary cells and of adenomatous lactotrophs. In the latter, Goα could be co-localized with prolactin (PRL). By immunoblots, using specific antisera, significant amounts of Goα and Gs42α, together with smaller amounts of Giα, Gs47α and Gβ were found to be present in the uncontaminated supernatant fraction of adenomatous lactotrophs. Unexpectedly, exposure of the cells to DA induced a rapid and short-lived decrease in the cytosolic fraction of Goα and Gβ associated with a decrease of PRL release. Since cytosolic Goα can be ADP-ribosylated by pertussis toxin (PT) and is therefore in a heterotrimeric form, our data suggest that the soluble Go protein may play a role during lactotrophs' exposure to an inhibitor of PRL release, perhaps through its relocalization after being internalized with the D₂ receptor or by being used for interaction with intracellular and/or membrane-bound effectors.     

Positive Outcome Expectancies and Smoking Behavior: The Role of Expectancy Accessibility

This study examined the association between smoking outcome expectancy accessibility and smoking behavior. Daily smokers completed a smoking expectancy accessibility task in which they made timed judgments to a series of positive consequences of smoking either after 6 hr deprivation or within 10 min of smoking. Participants then completed a questionnaire battery that contained assessments of smoking behavior and smoking outcome expectancies. Results of hierarchical regression analyses showed that expectancy accessibility was associated with the number of cigarettes smoked per day even when controlling for corresponding questionnaire measures of smoking expectancies. Moreover, smoking expectancy accessibility predicted urge to smoke ratings following exposure to a smoking cue after controlling for the effects of deprivation. Findings suggest that smoking expectancy accessibility may play a central role in smoking behavior and that individual differences in this attribute may be assessed directly through reaction time assessment.