The donor-acceptor approach allows a black-to-transmissive switching polymeric electrochrome.

In the context of the fast-growing demand for innovative high-performance display technologies, the perspective of manufacturing low-cost functional materials that can be easily processed over large areas or finely printed into individual pixels, while being mechanically deformable, has motivated the development of novel electronically active organic components fulfilling the requirements for flexible displays and portable applications. Among all technologies relying on a low-power stimulated optical change, non-emissive organic electrochromic devices (ECDs) offer the advantage of being operational under a wide range of viewing angles and lighting conditions spanning direct sunlight as desired for various applications including signage, information tags and electronic paper. Combining mechanical flexibility, high contrast ratios and fast response times, along with colour tunability through structural control, polymeric electrochromes constitute the most attractive organic electronics for tomorrow's reflective/transmissive ECDs and displays. Although red, blue and most recently green electrochromic polymers (ECPs) required for additive primary colour space were investigated, attempts to make saturated black ECPs have not been reported, probably owing to the complexity of designing materials absorbing effectively over the whole visible spectrum. Here, we report on the use of the donor-acceptor approach to make the first neutral-state black polymeric electrochrome. Processable black-to-transmissive ECPs promise to affect the development of both reflective and transmissive ECDs by providing lower fabrication and processing costs through printing, spraying and coating methods, along with good scalability when compared with their traditional inorganic counterparts.

Large bowel obstruction and perforation secondary to endometriosis complicated by a ventriculoperitoneal shunt.

A 36-year-old lady, with a past medical history of hydrocephalus requiring a ventriculoperitoneal (VP) shunt, was admitted with symptoms and signs of large bowel obstruction. Her condition worsened and she underwent laparotomy, where she had faecal peritonitis secondary to a perforated sigmoid colon. The shunt was contaminated with faeces leading to postoperative shunt infection and meningitis. Histology of the resected sigmoid colon revealed endometriosis at the site of perforation. Endometriosis is a rare cause of large bowel obstruction and literature review has found only two other cases of perforation because of endometriosis not associated with pregnancy. No case has been reported involving the concurrent surgical management of a contaminated VP shunt. We discuss the rarity of large bowel perforation and obstruction because of endometriosis, and the complications and management of VP shunts.

Predictors for acute and chronic pouchitis following restorative proctocolectomy for ulcerative colitis.

OBJECTIVE: This study was undertaken to evaluate the cumulative incidence, onset and risk predicting factors for acute and chronic pouchitis. METHOD: A consecutive series of patients (n = 210), who underwent restorative proctocolectomy (RPC) and had a minimum follow-up of 12 months was reviewed. The cumulative incidence and onset of pouchitis was determined. Univariate analysis, followed by logistic regression analysis was used to evaluate the association of various demographic, clinical and histopathologic variables with the subsequent development of acute and chronic pouchitis. RESULTS: A total of 198 patients were included. The mean follow-up was 64 months (range, 12-180). Sixty-four patients (32%) developed pouchitis, 35 acute and 29 chronic. The first episode of pouchitis occurred within the first year in 70% of cases. The presence of backwash ileitis (OR, 2.6; P = 0.015), primary sclerosing cholangitis (PSC; OR, 2; P = 0.018) and the duration of follow-up (OR, 1.1; P = 0.043) were associated with a higher incidence of pouchitis. The duration of follow-up was the only variable associated with acute pouchitis (P = 0.007). The presence of backwash ileitis and PSC were independent risk factors for chronic pouchitis (OR, 5.9; P < 0.001; OR, 2.8; P = 0.001 respectively). CONCLUSION: Pouchitis is a heterogeneous disease which tends to occur early after restoration of gastrointestinal continuity. Patients with backwash ileitis and/or PSC are at considerable risk of developing chronic pouchitis. The strong association between backwash ileitis, PSC and chronic pouchitis suggests a common link in their pathogenesis.

Referral of patients with iron deficiency anaemia under the lower gastrointestinal two-week wait rule.

OBJECTIVE: One of the 2-week wait (2WW) criteria for suspected lower gastrointestinal cancer states that patients should be referred who have iron deficiency anaemia (IDA) without obvious cause [Haemoglobin (Hb) <11 g/dl men, <10 g/dl postmenopausal women]. AIM: Our aim was to find the proportion of patients referred as a 2WW not meeting the criteria, and the cost accrued by unnecessary referral. METHOD: Patients referred over 1 year were identified using the hospitals cancer database. Haematology, haematinics, coeliac serology and cancer status were recorded for each patient. RESULTS: A total of 204 patients were referred. In total, only 22/204 patients (10.8%) met all the necessary criteria for diagnosis and investigation of IDA prior to referral. As only 43/204 (21.1%) had been assessed for coeliac serology, this accounted for the majority of incomplete referrals. Excluding coeliac serology, only 127 (62.3%) met 2WW criteria for IDA. Of the remaining 77 patients, 57 (74%) patients did not meet the 2WW criteria on Hb alone and 35/77 were referred with no evidence of IDA. 12/127 (9.4%) patients were diagnosed with colorectal cancer. No cancers were detected in patients without BSG evidence of IDA, although one patient did not meet the criteria on Hb level alone. CONCLUSION: Although iron deficiency is a good marker for gastrointestinal cancer, it is evident that 2WW referral guidelines are not being followed. 89.2% of referrals are inappropriate according to guidelines. This not only has considerable workload and financial implications but could be potentially detrimental to patient health.

3,4-Alkylenedioxypyrroles: functionalized derivatives as monomers for new electron-rich conducting and electroactive polymers.

New functionalized derivatives of 3,4-ethylenedioxypyrrole (EDOP, 5a) and 3,4-(1,3-propylenedioxy)pyrrole (ProDOP, 5b) as especially electron-rich monomers which yield highly electroactive and stable conducting polymers useful for a diverse set of applications have been synthesized. N-Alkylations of ProDOP were carried out to yield a variety of ProDOP derivatives having alkyl, sulfonatoalkoxy, glyme, and glyme alcohol pendant chains. Iodization of EDOP and ProDOP via iodo-decarboxylation afforded iodo-functionalized derivatives useful for subsequent aryl coupling chemistry. N-Protection and formylation of EDOP, followed by Knoevenagel condensation of the resultant 2-formyl-EDOP with aryl acetonitrile derivatives, led to 1-cyano-2-(2-(3,4-ethylenedioxypyrryl))-1-(2-thienyl)vinylene (23) (Th-CNV-EDOP) and 1-cyano-2-(2-(3,4-ethylenedioxypyrryl))-1-(2-(3,4-ethylenedioxythienyl)vinylene (26) (EDOT-CNV-EDOP). A 14-crown-4-ether 34 based dioxypyrrole was synthesized with a cavity potentially useful for lithium ion coordination and sensing in the resultant electroactive polymer. C-Alkylated ProDOPs (43a, 43b, and 43c) containing octyl, ethylhexyl, and dioctyl substituents appended to the central methylene of the propylene bridge, were prepared as monomers for potentially soluble pi-conjugated polymers.

Surgical management of infantile hypertrophic pyloric stenosis--can it be performed by general surgeons?

INTRODUCTION: Debate exists as to whether IHPS can be treated in district general hospitals as effectively as in specialist paediatric surgical units. AIM: To review the surgical treatment of IHPS in babies admitted to a district general hospital under the care of two consultant general surgeons with a paediatric surgical interest. PATIENTS AND METHODS: The case notes of 66 babies operated on for IHPS over a 42 month period between April 1995 and September 1998 were retrospectively reviewed. Demographics, operative details, hospital stay, and overall complications were all documented. RESULTS: Peri-operative complications occurred in 2 patients, both requiring omental patches for duodenal perforation. Nine patients had 1 or 2 episodes of postoperative vomiting; 4 had either a wound or urinary tract infection; and 1 baby developed an incisional hernia. There was no mortality. DISCUSSION: The complication rate seen in this series is comparable to that of specialist centres, and supports current guidelines suggesting that IHPS can be managed by general surgeons with a paediatric surgical interest in a district general hospital.

Faecal calprotectin levels in a high risk population for colorectal neoplasia.

BACKGROUND: Faecal concentrations of the protein calprotectin have been found to be elevated in patients with colorectal neoplasia, suggesting that it might be used as a screening tool for colorectal cancer as well as adenomas. AIMS: To measure the sensitivity and specificity of faecal calprotectin for the detection of adenomas in high risk individuals undergoing colonoscopy. Also, to investigate between and within stool variability of calprotectin concentrations. SUBJECTS: A total of 814 patients planned for colonoscopy were included for the following indications: positive faecal occult blood test, 25; neoplasia surveillance, 605; newly detected polyp, 130; and family risk, 54. METHODS: Two faecal samples from each of two stools were analysed using the PhiCal ELISA test device (Nycomed Pharma AS). RESULTS: Adenoma patients had significantly higher calprotectin levels than normal subjects (median 9.1 (95% confidence interval 7.5-10.1) v 6.6 (5.6-7.4)mg/l). There was no significant decrease in calprotectin levels after polypectomy. Levels in cancer patients were significantly higher than those in all other subgroups (median 17.6 mg/l (11.5-31.0)). With a cut off limit of 10 mg/l, the sensitivity for cancer was 74% and for adenoma 43%. Corresponding specificity values were 64% for no cancer and 67% for no neoplasia (cancer+adenoma). Specificity varied from 71% for one stool sample to 63% for four samples. Stool variability was small, suggesting that two spots from one stool were as discriminative as two spots from each of two stools. CONCLUSIONS: The sensitivity and specificity of faecal calprotectin levels as a marker for colorectal adenoma and carcinoma justifies its use in high risk groups, but specificity is too low for screening of average risk persons. Lack of a decrease in levels after polypectomy may be due to a more widespread leucocyte migration into the intestinal lumen than that at the polyp site, and needs further investigation.

Mesh repair of a coccygeal hernia via an abdominal approach.

We report on the presentation and management of a patient with herniation of the rectum following a coccygectomy. We used an abdominal approach and careful pelvic dissection to define the defect in the pelvic floor at the site where coccyx used to be. Prolene mesh repair resulted in the reduction of the hernia. To our knowledge, this is the first report on the mesh repair of the coccygeal hernia via an abdominal approach.

The effects of industrial employment conditions on job-related distress.

This paper examines the interaction between the effects of industrial unemployment and job conditions on workers' levels of psychological distress. Previous research finds that economic stress, defined as contexts of high unemployment, mainly affects distress indirectly through deteriorating job conditions. However, adaptive cost and identity salience hypotheses predict that the effects of industrial- and job-level conditions interact. I test for cross-level interactions between industrial unemployment and job demands and complexity using hierarchical linear modeling, individual data for 7,095 workers from the 1987-1988 National Survey of Families and Households, and industry data from the Bureau of Labor Statistics' 1986-1988 Current Population Surveys. Economic stress at the industrial level has a direct positive effect on worker distress, and economic stress is more distressing to workers in rewarding, complex jobs. In contrast, job demands increase distress, but this effect does not interact with industrial employment conditions.

Pharmacokinetic considerations in critical care.

As an applied science, pharmacokinetics permits the clinician to predict serum drug concentrations (SDCs) and associated pharmacologic responses, estimate dosage requirements, and assess unexpected drug responses. Therapeutic drug monitoring operationalizes the principles of pharmacokinetics through a multidisciplinary approach to the assessment and application of patient SDC data. Complicating the assessment of patients receiving these drugs is the tendency for physiologic changes and drug interactions to influence SDCs and associated pharmacologic responses. In determining the best dosing regimen for a particular patient, it is important to consider factors such as age, weight, major organ function, and concurrent drugs and disease states.

Haemothorax caused by a solitary costal exostosis.

A case of spontaneous haemothorax in a 14 year old boy due to trauma to the diaphragm caused by a solitary benign growth (exostosis) of a rib is described.

Aminoglycoside utilization study.

A retrospective review of aminoglycoside (AG) use in a tertiary care medical center/teaching hospital was conducted and use patterns were evaluated. Guidelines for AG use were approved by the Pharmacy and Therapeutics Committee and study criteria were developed to assess several parameters involving AG therapy, such as appropriateness of drug use, dosage, duration of therapy, and monitoring for toxicity. The study was conducted as part of a pharmacy quality assurance program in combination with the pharmacokinetic consultation service. A study population of 100 patients receiving an AG (gentamicin: 51, tobramycin: 33, amikacin: 16) was randomly selected from a total population of 250 patients who received AG therapy during August 1985. Medical patients accounted for 65% of AG use while surgical patients accounted for 30%. The majority of patients (84%) received an AG for an appropriate indication. Pretreatment culture/susceptibility and renal function was assessed for 89% and 91% of the patients, respectively. The study revealed problems with loading doses, maintenance doses and serum drug level monitoring. The majority of study patients did not have serum drawn for drug level determination at an appropriate time; therefore, dosage regimen decisions could not be made based on peak and trough values. No clinical nephrotoxicity was detected during treatments. The results of this study indicated the need for educating clinicians with respect to basic and applied AG pharmacokinetic principles and the importance of monitoring patients using the pharmacokinetic consultation service.

Pharmacokinetics of sufentanil in patients undergoing renal transplantation.

Renal failure and chronic haemodialysis are often associated with alterations in fluid status and plasma proteins. These changes, in turn, may result in pharmacokinetic alterations in affected patients. The purpose of this study was to investigate the pharmacokinetics of sufentanil in chronic renal failure patients undergoing kidney transplantation. Ten male patients were studied. Following induction of anaesthesia each patient received sufentanil 2.0 micrograms.kg-1 IV with subsequent serial plasma sampling for drug measurement from one to 360 minutes. A biexponential equation provided the best fit of the sufentanil concentration data with mean +/- SEM distribution (alpha) and elimination (beta) half-lives of 2.9 +/- 1.3 and 176 +/- 87 minutes, respectively. The mean Vc and Vd beta values were 0.15 +/- 0.05 L.kg-1 and 0.85 +/- 0.16 L.kg-1, respectively; plasma drug clearance was 11.5 +/- 3.7 ml.kg-1.min-1. Mean values for K10, K12 and K21 were 0.15 +/- 0.06.min-1, 0.4 +/- 0.14.min-1 and 0.1 +/- 0.04.min-1, respectively. With the exception of Vd beta, these pharmacokinetic values are similar to those reported in previous studies in general surgical, elderly and burn patients. The Vd beta values observed in this study may have resulted from alterations in drug distribution or elimination following revascularization of the implanted kidneys. Nevertheless, it appears that modification of sufentanil doses is unnecessary in chronic renal failure patients undergoing renal transplantation.

Comparative bioavailability of two oral sustained-release procainamide products.

The bioavailability characteristics of two sustained-release oral procainamide preparations, Procan SR and Pronestyl-SR, were compared in 10 patients with arrhythmias. Each patient was randomly assigned to receive either Procan SR 1 g or Pronestyl-SR 1 g, both administered orally every six hours. The initial drug was continued for 48 hours (eight doses), at which time the second drug, given at the same dosage and dosing interval, was substituted for a 48-hour period. Serum samples for procainamide determination were obtained hourly between 42 and 48 and between 90 and 96 hours after initiation of procainamide therapy. Values for area under the serum concentration-time curve (AUC) during the steady-state dosing interval, maximum serum drug concentration (Cmax), minimum serum drug concentration (Cmin), Cmax:Cmin ratio (representing fluctuations in serum drug concentrations within the dosing interval), and the time to maximum serum drug concentration (tmax) were determined. Mean ( +/- S.D.) tmax values for Procan SR and Pronestyl-SR were 2.2 +/- 0.8 hours and 3.8 +/- 1.1 hours, respectively. Only the differences between tmax values were statistically significant. The study had an 83% chance of detecting a 20% difference in AUC values. The chances of detecting a 20% difference in values for Cmax and Cmin were 62% and 71%, respectively. These two preparations would probably possess similar therapeutic properties when given at the same dosage and dosing schedule; however, studies with larger subject populations are needed to project bioavailability data to the general population.

Clearance of continuous intravenous morphine for severe cancer pain.

Four cancer patients with intractable pain received continuous morphine infusions in doses of 15-275 mg/h for a time period ranging from 4 to 27 days. Serum morphine concentrations were determined periodically following adjustments in infusion rates. As doses were changed and continued at static hourly rates, serum morphine concentrations were relatively constant 20 hours and beyond the time of the respective change, thus suggesting morphine elimination half-lives of less than or equal to 4 hours. High doses did not influence the time required to achieve steady-state concentrations. Steady serum morphine concentrations corresponded with hourly morphine doses in a parallel manner. High interpatient variabilities in clearances and steady-state serum morphine concentrations were noted. These data suggest that at morphine infusions up to 275 mg/h elimination pathways permit handling of increasing concentrations of morphine without nonlinear blood level increases. Also, marked interpatient and intrapatient variations in patient dose requirements were noted.