Fifty landmark discoveries in gastroenterology during the past 50 years. A brief history of modern gastroenterology at the millennium: Part II. Gastrointestinal motility, nutrition, and diseases of the lower gastrointestinal tract, liver, and pancreas

During the last half century, many outstanding discoveries have revolutionized the clinical practice and science of gastroenterology. Although the scientific results are widely disseminated, the discoverers have received inadequate recognition and the history of their discoveries is largely unstudied and unknown. At the millennium, a committee selected 50 landmark discoveries in gastroenterology during the past 50 years. A brief history of each landmark discovery is presented. Part I was presented in the previous issue of Gastroenterology Clinics of North America. Part II presents landmark discoveries in gastrointerintal (GI) motility, clinical trials, nutrition, and diseases of the lower GI tract, liver, biliary tree, and pancreas.     

The Tougher the Better: An Economic Analysis of Increased Payment Thresholds on the Performance of General Practices

We investigate whether and how a change in performance‐related payment motivated General Practitioners (GPs) in Scotland. We evaluate the effect of increases in the performance thresholds required for maximum payment under the Quality and Outcomes Framework in April 2006. A difference‐in‐differences estimator with fixed effects was employed to examine the number of patients treated under clinical indicators whose payment schedules were revised and to compare these with the figures for those indicators whose schedules remained unchanged. The results suggest that the increase in the maximum performance thresholds increased GPs' performance by 1.77% on average. Low‐performing GPs improved significantly more (13.22%) than their high‐performing counterparts (0.24%). Changes to maximum performance thresholds are differentially effective in incentivising GPs and could be used further to raise GPs' performance across all indicators. Copyright © 2013 John Wiley & Sons, Ltd.     

Growing your own: community health workers and jobs to careers

This article evaluates the implementation and impact of 5 workforce development programs aimed at achieving skills upgrades, educational advancement, and career development for community health workers (CHWs). Quantitative and qualitative case study data from the national evaluation of the Jobs to Careers: Transforming the Front Lines of Health Care initiative demonstrate that investing in CHWs can achieve measurable worker (eg, raises) and programmatic (eg, more skilled workers) outcomes. To achieve these outcomes, targeted changes were made to the structure, culture, and work processes of employing organizations. These findings have implications for other health care employers interested in developing their CHW workforce.     

Penetration of ammonium perfluorooctanoate through rat and human skin in vitro

Rat and human epidermal membranes were mounted onto in vitro diffusion cells with an exposure area of 0.64 cm2, and skin integrity was confirmed using electrical impedance. Following membrane selection, Fluorad FC-118, a 20% aqueous solution of ammonium perfluorooctanoate (AFPO), was applied to the epidermal surface of each skin replicate at approximately 150 microL/cm2 and the donor chamber opening occluded with Parafilm. Serial receptor fluid samples were collected hourly from 1 to 6 h and at 12, 24, 30, and 48 h and analyzed by liquid chromatography-mass spectrometry (LC-MS) for APFO anion (PFO-). For rat skin, the time to steady-state penetration (6500+/-3000 ng APFO x cm(-2) x h(-1)) occurred in less than 12 h, which was sustained until termination (48 h). Based on the concentration of the applied test material, the permeability coefficient (Kp) for APFO in rat skin was calculated to be 3.25+/-1.51 x 10(-5) cm/h. By end of the 48-h exposure period, only a small portion of the total APFO applied (1.44+/-1.13%) had penetrated through rat skin. For human skin, steady-state penetration of APFO (190+/-57 ng APFO x cm(-2) x h(-1)) was reached by 12 h. Based on the concentration of the applied test material, the permeability coefficient for APFO in human skin was calculated to be 9.49+/-2.86 x 10(-7) cm/h. By the end of the 48-h exposure period, only a negligible amount of the total APFO applied (0.048+/-0.01%) had penetrated through human skin. Thus, under infinite dose and occlusive conditions, the steady-state penetration of APFO from a 20% solution was approximately 34-fold faster through rat skin than human skin.     

Changes in the nasal carriage of drug-resistant Streptococcus pneumoniae in urban and rural Vietnamese schoolchildren

Studying the antimicrobial drug resistance of nasopharyngeal or nasal carriage isolates of Streptococcus pneumoniae in children is likely to have predictive potential for invasive isolates. Streptococcus pneumoniae nasal carriage was studied in 1422 Vietnamese children. Forty-six percent of 536 isolates showed reduced susceptibility to penicillin and 7% showed intermediate susceptibility to ceftriaxone; and 50% of 518 isolates showed resistance to erythromycin. All isolates were sensitive to levofloxacin and gatifloxacin. Urban and suburban children were significantly more likely to carry drug-resistant isolates than rural children. Rates of non-susceptibility to penicillin and erythromycin increased significantly in the rural province Khanh Hoa in 2003/2004 compared with rates obtained in 1997. An emerging clone of penicillin non-susceptible S. pneumoniae of serogroup 15 was identified, which was widely distributed in addition to the pandemic clones Spain(23F)-1 and Taiwan(19F)-14. Although resistance to fluoroquinolones was not observed, 6 (18%) of 34 isolates had a Lys137Asn mutation in the parC gene. This study shows that drug resistance is increasing in carriage isolates of S. pneumoniae in rural areas in Vietnam owing to spread of pandemic and emerging resistant clones.     

Comparative and Mixture Sediment Toxicity of Trinitrotoluene and Its Major Transformation Products to a Freshwater Midge

The explosive trinitrotoluene (TNT) is a prevalent contaminant in many military installations worldwide. Limited knowledge of the comparative toxicity of sediment-associated TNT and related compounds contributes to uncertainty when assessing ecological risks in contaminated sites. Trinitrotoluene undergoes transformation when associated with soils and sediments and typically occurs as a mixture dominated by its reduction products. The objective of this study was to comparatively evaluate the single-compound toxicity of TNT and its major transformation products to the freshwater midge Chironomus tentans in 10-day exposures to sediment spiked with TNT, 2-aminodinitrotoluene (2-ADNT), 2,4-diaminonitrotoluene (2,4-DANT), or trinitrobenzene (TNB). In addition, the nature of the toxicological interactions of the latter compounds in a mixture was evaluated. Upon spiking to sediment, TNT and TNB rapidly degraded to reduced products, and disappearance of extractable compounds suggested irreversible binding to sediment particles. The high degree of transformation and reactivity occurring during 10 days at spiking concentrations as high as 4000 μmol/kg dry weight suggests that TNT and related compounds are unlikely to be encountered in fine-grained sediments at contaminated sites. Similar to previous investigations, the high reactivity of the spiked compound hampered determination of accurate toxic concentrations of TNT and related compounds, and of the nature of toxicological interaction of compounds in a mixture in this study. Sediment concentrations associated with decreased survival were similar for all four compounds, with the 10-d median lethal concentrations (LC50s) determined using initial concentrations ranging from 175 (2-ADNT) to 605 (2,4-DANT) μmol/kg dry weight. Sublethal decrease in growth was not observed for any compound. Results from the mixture experiment suggest additive interaction among TNT and related compounds in sediment exposures.     

Selective serotonin reuptake inhibitor-induced rash: case report and review of the literature

Selective serotonin reuptake inhibitors (SSRIs) are one of the most frequently prescribed classes of drugs. Rashes induced by SSRIs seldom have been reported in the literature. Computerized MEDLINE and Current Contents searches yielded a report of two cases of rash induced specifically by paroxetine. We describe a patient who developed a rash that appeared on day 3 of treatment with oral paroxetine 20 mg/day. Her rash was morbilliform, pruritic, and generalized over the trunk and limbs, with some facial involvement. There was no palm or sole involvement. The patient reported that she had experienced a similar reaction to fluoxetine, which may suggest a drug class effect. The rash resolved within 2 days of drug discontinuation and treatment with oral diphenhydramine and topical hydrocortisone cream.     

The conservative management of patients with symptoms of stress incontinence: a randomized, prospective study comparing weighted vaginal cones and interferential therapy

Sixty-nine female patients with symptoms of stress urinary incontinence were randomized to treatment with either interferential therapy or weighted vaginal cones. Fifty-four patients completed treatment (interferential therapy, 30 patients; weighted vaginal cones, 24 patients). Patients were assessed by subjective response, pad testing, continence charts, and the maximum weight of cone that could be held actively and passively. Forty-seven patients were reassessed at 6 months (19 cones; 28 interferential), five patients (9.26%) required surgery, and two patients (3.7%) could not be reassessed. Subjective response to treatment was good, with 80% to 90% of patients cured or improved after treatment. After 6 months, 41.67% in the cone group and 40% in the interferential group were subjectively cured, with improvement in 50% and 30%, respectively. Of those patients initially referred for treatment, greater than 30% in each group were cured of symptoms. There was an objective improvement in both groups. In the cone group 50% had improved after treatment and greater than 60% had improved at 6 months as assessed by pad testing, while in the interferential group 76% had improved after treatment and 73% had improved at 6 months. There was no significant difference in improvement between the two groups in any of the methods of assessment. However, the cones require less supervision by trained staff and can be used at home by the patient. Their use results in a savings in time for the physiotherapy department. The use of the cones is recommended as a cost-effective method of treatment that can be added to the present therapy options available to the physiotherapist.