Attempted suicide in west London, II. Inter-group comparisons

BACKGROUND: Previous studies of attempted suicide have suggested that cultural and social factors play a significant role in the causation of deliberate self-harm. METHOD: In order to measure elements of culture conflict two inter-group comparisons were undertaken. In the first, 27 Asian women who had presented to hospital services following attempted suicide (Asian group) were matched with a group of similar age Asian women attending GP surgeries for other reasons (Asian GP attenders group). The second comparison was between the Asian and 46 White attempters. RESULTS: On comparing Asian attempters with Asian GP attenders group the former were more likely to have a history of previous suicidal behaviour, to have a psychiatric diagnosis, and be unemployed. Their parents were more likely to have arrived in the United Kingdom at an older age. In addition, those who attempted suicide were more likely to have been in an inter-racial relationship and to have changed religions. In the second inter-group comparison, the characteristics of Asian and White suicide attempt patients were examined. White attempters were more likely to have mental illness, and were more likely to use alcohol as part of the method of attempted suicide. By contrast, Asian attempters had experienced life events pertaining to relationships, took fewer tablets and yet expressed greater regret at not succeeding in the attempt. CONCLUSIONS: Although numbers are small, social stress and other cultural factors play an important role in the act of deliberate self-harm.     

Surface-immobilized polyethylene oxide for bacterial repellence.

Polyethylene terephthalate films were surface-modified with polyethylene oxide (18,500 g/mol) using a solution technique described previously. These films were investigated for their resistance to bacterial adhesion. Three bacterial strains most commonly associated with implant infections, Staphylococcus epidermidis, Staphylococcus aureus and Pseudomonas aeruginosa, were cultured in tryptic soya broth, human plasma and human serum on the polymeric substrates. Significant reductions (between 70 and 95%) in adherent bacteria were observed on the polyethylene oxide-modified substrates compared to the untreated control polyethylene terephthalate. Surface modification with polyethylene oxide may reduce the risk of implant-associated infections. Plasma fibrinogen was observed to play an important role in the adhesion of all three of these species on both the polyethylene oxide-modified and control polyethylene terephthalate materials.     

Adenosine A2A Receptor Agonists Promote More Rapid Wound Healing Than Recombinant Human Platelet–Derived Growth Factor (Becaplermin Gel)

Animal studies of the topical application of adenosine A _2A receptor agonists show that it promotes wound closure. To further confirm the efficacy of adenosine A _2A receptor agonists as promoters of wound healing, we compared the effect of MRE0094, a novel selective adenosine A _2A receptor agonist, to CGS-21680, a reference selective adenosine A _2A receptor agonist, as well as to recombinant human platelet–derived growth factor (0.01% Becaplermin gel), an agent currently used to promote healing of diabetic ulcers, on wound closure in healthy BALB/C mice. Wounds (12 mm diameter) were created on the dorsum of mice (two per mouse) and then treated daily with vehicle, 0.01% Becaplermin gel, or different doses of the adenosine A _2A receptor agonists. The wound margins were traced onto plastic sheets, and the wound areas were digitized, quantitated, and compared. We found that application of MRE0094 (1 g/wound and 10 g/wound) and CGS-21680 (1 g/wound and 5 g/wound) achieved 50% wound closure significantly more rapidly than control application (day 1.9, 1.9, 3.5, 3.2, respectively, versus control day 4, p < 0.05 ANOVA). Surprisingly, neither higher nor lower concentrations of CGS-21680 affected the rate of wound closure, as compared to control. In contrast, Becaplermin gel did not increase the rate at which wounds closed (50% closure by day 7.2, p = NS versus control). These data confirm our prior observations that adenosine A _2A receptor agonists promote wound closure, and they suggest that these agents may be as effective if not more effective than Becaplermin gel for the treatment of poorly healing wounds.     

Loxosceles deserta Spider Venom Induces the Expression of Vascular Endothelial Growth Factor (VEGF) in Keratinocytes

Evenomation by arachnids of the genus Loxosceles frequently results in disfiguring necrotic skin lesions. The cellular and molecular mechanisms which contribute to lesion development are incompletely defined but appear to involve participation of several pro-inflammatory mediators. We have recently observed that Loxosceles deserta venom induces the production of chemokines in human umbilical vein endothelial cells (HUVECs) and human pulmonary epithelial cells. In the present study we observed that Loxosceles deserta venom induces the expression of vascular endothelial growth factor (VEGF) in human keratinocytes but little in smooth muscle cells and none in pulmonary epithelial cells. A potent endothelial cell-specific mitogen, VEGF induces angiogenesis and vascular permeability in vivo. RNase protection assay data indicate that VEGF mRNA concentrations in keratinocytes are significantly increased at 2 h following venom exposure. These data suggest that keratinocyte-derived VEGF may contribute to the vasodilation, edema and erythema which occur following Loxosceles evenomation.     

Persistent tubular conduction in vacuolated amphibian skeletal muscle following osmotic shock

The transverse (T-)tubules primarily function in conducting the action potentials that initiate excitation– contraction coupling in skeletal muscle but may additionally subserve longer-term roles in volume regulation, membrane fusion and other trafficking processes. Osmotic shock thus both electrically detaches the T-tubules from surface membrane (‘detubulation’) and produces tubular vacuolation. The present experiments separated these effects. An established, reference osmotic shock protocol that exposed muscles to Ca²⁺/Mg²⁺-Ringer and gradual cooling to 10°C after 18 min in glycerol–Ringer accomplished significant detubulation (77.5 ± 13.15%, mean ± SEM; n = 4). In contrast, a test protocol conducted entirely at room temperature using Mg²⁺-rather than Ca²⁺/Mg²⁺-Ringer yielded reduced (P < 0.05, post hoc Duncan's multiple range test) detubulation indices (1.67 ± 1.67%, n = 6) statistically indistinguishable from findings in fibres spared osmotic shock. Yet both osmotic shocks caused a formation of closed vacuoles, demonstrated by Sulphorhodamine B trapping, that occupied statistically similar fractions of total fibre volume (reference procedure: 14.38 ± 2.7%, n = 6; test procedure: 13.36 ± 2.00%, n = 22) in turn higher than determinations in control fibres (P < 0.05). The findings reconcile reports associating detubulation with vacuolation in osmotically shocked muscle [S. Nik-Zainal et al. (1999) J Muscle Res Cell Motil 20: 45–53; K.N. Khan et al. (2000) J Muscle Res Cell Motil 21: 79–90] with the persistence of tubular electrical activity in extensively vacuolated amphibian fibres following fatigue [J. Lannergren and H. Westerblad (1987) Acta Physiol Scand 129: 311–318; J. Lannergren et al. (1999) J Muscle Res Cell Motil 20: 19–32]. Furthermore test protocols produced higher densities of open vacuoles (13.38 ± 2.33%, n = 9) than did reference protocols (6.66 ± 1.63%, n = 20) contrary to their possible involvement in the electrophysiological changes. Abolition of tubular electrophysiological activity thus either follows or is independent of tubular vacuolation whilst sharing some of its underlying osmotic mechanisms. This revised version was published online in July 2006 with corrections to the Cover Date.     

Fifteen years experience with an in-vitro fertilization surrogate gestational pregnancy programme

The purpose of our study was to review and evaluate retrospectively the experience of an in-vitro fertilization (IVF) surrogate gestational programme in a tertiary care and academic centre. In a 15 year period from 1984 to 1999, a total of 180 cycles of IVF surrogate gestational pregnancy was started in 112 couples. On average, the women were 34.4 +/- 4.4 years of age, had 11.1 +/- 0.72 oocytes obtained per retrieval, 7.1 +/- 0.5 oocytes fertilized and 5. 8 +/- 0.4 embryos subsequently cleaved. Sixteen cycles (8.9%) were cancelled due to poor stimulation. Except for six cycles (3.3%) where there were no embryos available, an average of 3.2 +/- 0.1 embryos was transferred to each individual recipient. The overall pregnancy rate per cycle after IVF surrogacy was 24% (38 of 158), with a clinical pregnancy rate of 19% (30 of 158), and a live birth rate of 15.8% (25 of 158). When compared to patients who underwent a hysterectomy, individuals with congenital absence of the uterus had significantly more oocytes retrieved (P < 0.006), fertilized, cleaved and more embryos available for transfer despite being of comparable age. IVF surrogate gestation is an established, yet still controversial, approach to the care of infertile couples. Take-home baby rates are comparable to conventional IVF over the same 15 year span in our programme. Patients with congenital absence of the uterus responded to ovulation induction better than patients who underwent a hysterectomy, perhaps due in part to ovarian compromise from previous surgical procedures.