Risk and significance of endoscopic/radiological evidence of recurrent Crohn's disease

BACKGROUND & AIMS: The aim of this study was to determine the risk of endoscopic/radiological recurrence of Crohn's disease postoperatively and the long-term outcome. METHODS: A randomized placebo-controlled trial was performed to determine the effectiveness of mesalamine in preventing recurrent Crohn's disease postoperatively. Patients in the control group were examined endoscopically/radiologically before entry into and annually during the trial. Findings were classified as minimal or severe. RESULTS: There were 76 patients (49 men and 37 women; mean age, 37.1 +/- 13.2 years). Fifty (61.7%) had terminal ileal resections. Overall, 55 endoscopic/radiological recurrences were observed in 51 patients (67.1%). Expressed actuarially, the recurrence rate was 27.5% at 1 year (95% confidence interval [CI], 15.8%-37.6%), 60.8% at 2 years (95% CI, 46%-71.3%), and 77.3% at 3 years (95% CI, 62.7%-86.3%). Nineteen (37%) were symptomatic and 12 (24%) were initially asymptomatic but later became symptomatic (mean, 13.0 +/- 8.8 months), whereas 20 (39%) remained asymptomatic (mean, 16.9 +/- 17.4 months). Patients with severe endoscopic/radiological disease were significantly more likely to be or become symptomatic than those with minimal disease (23 of 32 vs. 8 of 19, respectively; P = 0.0437). CONCLUSIONS: This study suggests that postoperative endoscopic/radiological recurrences occur later than previously reported. Furthermore, many of these patients, especially with minimal disease, will remain asymptomatic. (Gastroenterology 1997 Dec;113(6):1823-7)     

利福昔明：有效维持肝性脑病缓解

肝性脑病是的一种慢性消耗性的肝硬化并发症。利福昔明（rifaximin）,一种口服的抗生素,治疗急性肝性脑病的疗效已有报道,但其预防此病疗效未知。     

Massage therapy after heart surgery: possibly pleasant,but not effective

Albert NM, Gillinov AM, Lytle BW, Feng J, Cwynar R, Blackstone EH. A randomized trial of massage therapy after heart surgery. Heart Lung 2009; 38: 480–90.     

Morphometric MRI findings in the thalamus and brainstem in children after moderate to severe traumatic brain injury

Generalized whole brain volume loss is well documented in moderate to severe traumatic brain injury. Whether this atrophy occurs in the thalamus and brainstem has not been systematically studied in children. Magnetic resonance imaging (MRI) quantitative analysis was used to investigate brain volume loss in the thalamus and brainstem in 16 traumatic brain injury subjects (age range 9-16 years) compared with 16 age and demo-graphically matched controls. Based on multiple analysis of covariance, controlling for age and head size, reduced volume in the thalamus and the midbrain region of the brainstem were found. General linear model analyses revealed a relation between processing speed on a working memory task and midbrain and brain stem volumes. Reduced volume in thalamic and brainstem structures were associated with traumatic brain injury. Reduction in midbrain and thalamic volume is probably a reflection of the secondary effects of diffuse axonal injury and reduction in cortical volume from brain injury.     

Computer simulation in conjunction with medical thermography as an adjunct tool for early detection of breast cancer

Background

Mathematical modelling and analysis is now accepted in the engineering design on par with experimental approaches. Computer simulations enable one to perform several 'what-if' analyses cost effectively. High speed computers and low cost of memory has helped in simulating large-scale models in a relatively shorter time frame. The possibility of extending numerical modelling in the area of breast cancer detection in conjunction with medical thermography is considered in this work.

Methods

Thermography enables one to see the temperature pattern and look for abnormality. In a thermogram there is no radiation risk as it only captures the infrared radiation from the skin and is totally painless. But, a thermogram is only a test of physiology, whereas a mammogram is a test of anatomy. It is hoped that a thermogram along with numerical modelling will serve as an adjunct tool. Presently mammogram is the 'gold-standard' in breast cancer detection. But the interpretation of a mammogram is largely dependent on the radiologist. Therefore, a thermogram that looks into the physiological changes in combination with numerical simulation performing 'what-if' analysis could act as an adjunct tool to mammography.

Results

The proposed framework suggested that it could reduce the occurrence of false-negative/positive cases.

Conclusion

A numerical bioheat model of a female breast is developed and simulated. The results are compared with experimental results. The possibility of this method as an early detection tool is discussed.

     

Evidence for van der Waals adhesion in gecko setae

Geckos have evolved one of the most versatile and effective adhesives known. The mechanism of dry adhesion in the millions of setae on the toes of geckos has been the focus of scientific study for over a century. We provide the first direct experimental evidence for dry adhesion of gecko setae by van der Waals forces, and reject the use of mechanisms relying on high surface polarity, including capillary adhesion. The toes of live Tokay geckos were highly hydrophobic, and adhered equally well to strongly hydrophobic and strongly hydrophilic, polarizable surfaces. Adhesion of a single isolated gecko seta was equally effective on the hydrophobic and hydrophilic surfaces of a microelectro-mechanical systems force sensor. A van der Waals mechanism implies that the remarkable adhesive properties of gecko setae are merely a result of the size and shape of the tips, and are not strongly affected by surface chemistry. Theory predicts greater adhesive forces simply from subdividing setae to increase surface density, and suggests a possible design principle underlying the repeated, convergent evolution of dry adhesive microstructures in gecko, anoles, skinks, and insects. Estimates using a standard adhesion model and our measured forces come remarkably close to predicting the tip size of Tokay gecko seta. We verified the dependence on size and not surface type by using physical models of setal tips nanofabricated from two different materials. Both artificial setal tips stuck as predicted and provide a path to manufacturing the first dry, adhesive microstructures.     

Contaminant Loading in Drainage and Fresh Water Used for Wetland Management at Stillwater National Wildlife Refuge

Throughout the western United States, studies have identified various detrimental effects of contaminants to aquatic biota from the use of agricultural drainage water for management of arid wetlands. However, little is known about the relative contributions of contaminant loading from pollutants dissolved in water compared with those carried by drifting material (e.g., detritus) associated with drainage water. Consequently, we determined loading rates for contaminants dissolved in water and those incorporated by drifting material for drainage (Diagonal Drain) as well as fresh (S-Line Canal) water used for wetland management at Stillwater National Wildlife Refuge (SNWR), Nevada during the early, middle, and late periods of the irrigation season (June through mid-November) in 1993. We found loading rates for trace elements throughout the irrigation season were almost entirely (> 98%) associated with contaminants dissolved in the water rather than incorporated by drift. Although drift contributed little to the total loading for trace elements to SNWR wetlands, contaminant concentrations were much greater in drift compared with those dissolved in water. Loading rates for dissolved As, B, Hg, and total dissolved solids (TDS) differed among periods for the Diagonal Drain. Along the Diagonal Drain, loading rates for dissolved As, B, Hg, Mo, unionized ammonia (NH₃-N), TDS, and Zn differed among its three sampling sites. B was the only trace element with differences in loading rates for drift among periods from the Diagonal Drain. In contrast, loading rates for As, B, Cr, Cu, Hg, Se, and Zn in drift differed among periods for the S-Line Canal. Along Diagonal Drain, loading rates in drift for B (middle and late periods), Cr, Cu, and Zn differed among sites. Hg (xˉ ≥ 12.0 ng/L) and NH₃-N (xˉ ≥ 0.985 mg/L) dissolved in water as well as B (xˉ ≥ 97.4 μg/g DW) and Hg (xˉ ≥ 0.461 μg/g DW) in drift from the Diagonal Drain and S-Line Canal exceeded screening levels (SLs) for protection of aquatic biota throughout the irrigation season. Dissolved As (xˉ ≥ 0.0426 mg/L) in water from the Diagonal Drain during all periods exceeded the SL for protection of aquatic biota. Dissolved B (xˉ = 1.03 mg/L) in water from the Diagonal Drain during the early period exceeded the SL for protection of aquatic biota. Received: 18 September 1997/Accepted: 5 February 1998     

High-dose weekly AmBisome antifungal prophylaxis in pediatric patients undergoing hematopoietic stem cell transplantation: a pharmacokinetic study.

Disseminated fungal infection causes significant morbidity and mortality in children undergoing hematopoietic stem cell transplantation (HSCT). The widespread use of prophylactic oral triazoles has limitations of poor absorption, interindividual variability in metabolism, and hepatic toxicity. AmBisome (amphotericin B liposomal complex) has a better safety profile than the parent drug amphotericin B and produces higher plasma and tissue concentrations. We hypothesized that once-weekly high-dose AmBisome therapy could provide adequate fungal prophylaxis for immunocompromised children undergoing HSCT. We performed a pharmacokinetic pilot study to determine whether once-weekly high-dose AmBisome administration would result in effective concentrations throughout the dosing interval. A total of 14 children (median age, 3 years, 1 month; range, 4.5 months-9 years, 9 months) undergoing HSCT received once-weekly intravenous AmBisome prophylaxis (10 mg/kg as a 2-hour infusion). Blood samples for pharmacokinetic measurements were drawn around the first and the fourth weekly doses. The concentration of non-lipid-complexed amphotericin in plasma was determined by a validated bioassay. Pharmacokinetic parameters after single doses and during steady state were calculated using standard noncompartmental methods. AmBisome was well tolerated at this dose. Complete pharmacokinetic profiles for weeks 1 and 4 were obtained in 12 patients. The half-life calculated in this pediatric population was shorter on average than reported in adults (45 hours vs 152 hours). The volume of distribution correlated best with body weight (R(2) = .55), and clearance was best predicted by initial serum creatinine level (R(2) = .19). Mean (+/- standard deviation) individual plasma trough concentrations were 0.23 (0.13) mg/L after single doses and 0.47 (0.41) mg/L after multiple doses. Mean steady-state area under the curve was higher at week 4 than after a single dose (P < .05). Single-dose and steady-state pharmacokinetic profiles were similar in 8 patients, whereas in 4 patients the week 4 profile showed nonlinear elimination. However, plasma concentrations at 7 days (Cmin) were not significantly different after the first and fourth doses, suggesting no significant accumulation over the course of therapy. Our data show measurable amphotericin B plasma concentrations 7 days after high-dose infusion of AmBisome. This suggests that once-weekly dosing, as described in this study, may provide useful protection against fungal infections.