From tails to toes: developing nonlethal tissue indicators of mercury exposure in five amphibian species

Exposure to environmental contaminants has been implicated as a factor in global amphibian decline. Mercury (Hg) is a particularly widespread contaminant that biomagnifies in amphibians and can cause a suite of deleterious effects. However, monitoring contaminant exposure in amphibian tissues may conflict with conservation goals if lethal take is required. Thus, there is a need to develop non-lethal tissue sampling techniques to quantify contaminant exposure in amphibians. Some minimally invasive sampling techniques, such as toe-clipping, are common in population-genetic research, but it is unclear if these methods can adequately characterize contaminant exposure. We examined the relationships between mercury (Hg) concentrations in non-lethally sampled tissues and paired whole-bodies in five amphibian species. Specifically, we examined the utility of three different tail-clip sections from four salamander species and toe-clips from one anuran species. Both tail and toe-clips accurately predicted whole-body THg concentrations, but the relationships differed among species and the specific tail-clip section or toe that was used. Tail-clips comprised of the distal 0–2 cm segment performed the best across all salamander species, explaining between 82 and 92 % of the variation in paired whole-body THg concentrations. Toe-clips were less effective predictors of frog THg concentrations, but THg concentrations in outer rear toes accounted for up to 79 % of the variability in frog whole-body THg concentrations. These findings suggest non-lethal sampling of tails and toes has potential applications for monitoring contaminant exposure and risk in amphibians, but care must be taken to ensure consistent collection and interpretation of samples.     

The D-Net diabetes self-management program: long-term implementation, outcomes, and generalization results

BACKGROUND: A prerequisite to translating research findings into practice is information on consistency of implementation, maintenance of results, and generalization of effects. This follow-up report is one of the few experimental studies to provide such information on Internet-based health education. METHODS: We present follow-up data 10 months following randomization on the "Diabetes Network (D-Net)" Internet-based self-management project, a randomized trial evaluating the incremental effects of adding (1) tailored self-management training or (2) peer support components to a basic Internet-based, information-focused comparison intervention. Participants were 320 adult type 2 diabetes patients from participating primary care offices, mean age 59 (SD = 9.2), who were relatively novice Internet users. RESULTS: All intervention components were consistently implemented by staff, but participant website usage decreased over time. All conditions were significantly improved from baseline on behavioral, psychosocial, and some biological outcomes; and there were few differences between conditions. Results were robust across on-line coaches, patient characteristics, and participating clinics. CONCLUSIONS: The basic D-Net intervention was implemented well and improvements were observed across a variety of patients, interventionists, and clinics. There were, however, difficulties in maintaining usage over time and additions of tailored self-management and peer support components generally did not significantly improve results.     

Follow-up phone calls increase nutrient intake estimated by three-day food diaries in 13-year-old participants of the Raine study

Aim: Our primary objective was to determine the effect of follow‐up phone calls on estimated nutrient intakes obtained by three‐day food diaries from 13‐year‐old adolescents. Methods: Food diaries were recorded using household measures and entered into a dietary analysis software program, before and after follow up by telephone. A sample of 340 participants aged 13 years born into the Western Australian Pregnancy Cohort (Raine) Study, a population‐based longitudinal cohort followed from 16 to 20 weeks' gestation to 13 years of age (current follow up). After face‐to‐face instruction, participants completed three‐day food diaries at home and returned them by post. Follow‐up telephone calls were made to each participant to improve data collection response and to verify missing details in the food diaries. Nutrient intakes before and after telephone follow up were compared using Student's t‐tests in spss . Results were also compared with those of the Child and Adolescent Physical Activity and Nutrition survey. Results: Follow‐up phone calls significantly increased the estimated intake of total kilojoules, water, total carbohydrates, sugars and magnesium (P < 0.05). Conclusion: These results indicate the importance of follow‐up phone calls to obtain missing details in three‐day food diaries completed by adolescents.     

Thioredoxin reductase and cancer cell growth inhibition by organogold(III) compounds

Thioredoxin (Trx) expression is increased in several human primary cancers associated with aggressive tumor growth and decreased patient survival, and the Trx/Trx reductase (TrxR) system therefore provides an attractive target for cancer drug development. Various gold(III) compounds with none, one, two or three carbon-gold bonds were evaluated for their capacity to inhibit TrxR and the growth of MCF-7 cancer cells in vitro. Compounds with up to two carbon-gold bonds were often potent inhibitors of TrxR with IC50 values as low as 2 nmol/l. In the presence of Trx and insulin the inhibiting capacity was much lower. However, the inhibitory concentrations of the compounds did not correlate with the ability to kill cells. Out of the organometallics tested, only compound 8 with two carbon-gold bonds was able to inhibit colony formation by MCF-7 breast cancer cells at low micromolar concentrations (IC50=1.6 micromol/l). Unfortunately, the compound did not show any anti-tumor activity against MCF-7 breast cancer and HT-29 colon cancer xenografts in scid mice.     

Immediate transepithelial photorefractive keratectomy for treatment of laser in situ keratomileusis flap complications

PURPOSE: To study the role of photorefractive keratectomy (PRK) in the management of laser in situ keratomileusis (LASIK) flap complications. METHODS: A retrospective analysis was performed of seven patients (14 eyes) who had bilateral, simultaneous LASIK (single surgeon [TGA], Summit Apex Plus laser, Hansatome microkeratome in six patients [12 eyes], Automated Corneal Shaper keratome in one patient [two eyes]). One eye of each patient received PRK for a flap complication. The seven patients (four women, three men) had a mean age of 39.2 years (range, 22 to 64 yr). The uncomplicated LASIK eyes had moderate to high myopia (-2.25 to -8.75 D) and the eyes with LASIK flap complications had mild to moderate myopia (-1.50 to -5.75 D). Immediate transepithelial PRK was performed in all eyes after repositioning the defective flap. RESULTS: All seven patients had excellent visual outcome at 6 months follow-up; one patient required an enhancement (astigmatic keratotomy). Six of the seven LASIK eyes had best spectacle-corrected visual acuity of 20/20 or better and one LASIK eye had 20/25. In the transepithelial PRK eyes, six of the seven eyes had best spectacle-corrected visual acuity of 20/20 or better and one eye had 20/30. CONCLUSIONS: Immediate transepithelial PRK treatment of irregular and incomplete LASIK flaps at the time of surgery is an excellent therapeutic option to delayed surgical treatment.     

Short-term outcomes for super-super obese (BMI > or =60 kg/m2) patients undergoing weight loss surgery at a high-volume bariatric surgery center: laparoscopic adjustable gastric banding, laparoscopic gastric bypass, and open tubular gastric bypass

BACKGROUND: We previously reported significantly longer operating room times and a trend toward increased complications and mortality in the super-super obese (body mass index [BMI] > or =60 kg/m(2)) early in our experience with laparoscopic Roux-en-Y gastric bypass. The goal of this study was to re-examine the short-term outcomes for super-super obese patients undergoing weight loss surgery at our high-volume bariatric surgery center well beyond our learning curve. METHODS: The records for all patients who had undergone weight loss surgery at Hackensack University Medical Center from 2002 to June 2006 were harvested from the hospital's electronic medical database. This population was analyzed as 2 groups (those with a BMI <60 kg/m(2) and those with a BMI > or =60 kg/m(2)), as well as by type of operation. Step-wise and univariate logistic regression analyses assessed the effect of BMI on the outcome variables, including mortality, length of surgery, length of hospital stay, and disposition at discharge. RESULTS: A total of 3692 patients were studied. Of these patients, 3401 had a BMI <60 kg/m(2) and 291 had a BMI > or =60 kg/m(2). Of the 291 super-super obese patients, 130 underwent vertical banded gastroplasty-Roux-en-Y gastric bypass, 116 laparoscopic Roux-en-Y gastric bypass, and 45 laparoscopic adjustable gastric banding. The proportion of male patients, black patients, and patients with sleep apnea was increased in the BMI > or =60 kg/m(2) group. The number of co-morbid diseases per patient correlated with age but not BMI. The BMI > or =60 kg/m(2) group required a significantly longer total operating room time (136 versus 120 min). Hospital length of stay was significantly longer only in the laparoscopic Roux-en-Y gastric bypass patients (3 d for the BMI > or =60 kg/m(2) group versus 2 d for the BMI <60 kg/m(2) group). A significantly greater percentage of patients in the super-super obese group were discharged to chronic care facilities. The overall in-hospital mortality rate was 0.15% (5 of 3692) but did not significantly differ between the 2 groups: BMI <60 kg/m(2), rate of 0.12% (4 of 3401 patients), and BMI > or =60 kg/m(2), rate of 0.34% (1 of 291 patients). The type of operation did not significantly affect the disposition at discharge or in-hospital mortality. CONCLUSION: Super-super obese patients required longer total operating room times, a longer hospital length of stay, and were more likely to be discharged to chronic care facilities than were patients with a BMI <60 kg/m(2); however, the in-hospital mortality was similar for both groups.     

Asiatic acid and corosolic acid enhance the susceptibility of Pseudomonas aeruginosa biofilms to tobramycin

Asiatic acid and corosolic acid are two natural products identified as biofilm inhibitors in a biofilm inhibition assay. We evaluated the activities of these two compounds on Pseudomonas aeruginosa biofilms grown in rotating disk reactors (RDRs) in combination with tobramycin and ciprofloxacin. To determine the ruggedness of our systems, the antibiotic susceptibilities of these biofilms were assessed with tobramycin and ciprofloxacin. The biofilm bacteria produced in the RDR were shown to display remarkable tolerance to 10 mug/ml of ciprofloxacin, thus mimicking the tolerance observed in recalcitrant bacterial infections. These studies further demonstrate that a nonmucoid strain of P. aeruginosa can form a biofilm that tolerates ciprofloxacin at clinically relevant concentrations. Neither asiatic acid nor corosolic acid reduced the viable cell density of P. aeruginosa biofilms. However, both compounds increased the susceptibility of biofilm bacteria to subsequent treatment with tobramycin, suggesting asiatic acid and corosolic acid to be compounds that potentiate the activity of antibiotics. A similar statistical interaction was observed between ciprofloxacin and subsequent treatment with tobramycin.