KIDCLOT: the importance of validated educational intervention for optimal long term warfarin management in children

BACKGROUND

Advances in medical and surgical therapy in children have resulted in increased survival in children with primary illnesses. However, thrombosis is a serious complication of this success and results in mortality and morbidity. Prevention or treatment of thrombosis using warfarin is challenging in children due to its narrow therapeutic index and the unique differences in children, including variable nutritional intake and the occurrence of common concomitant viral or bacterial illnesses which alter warfarin metabolism. The variable response to warfarin in children necessitates frequent International Normalized Ratio (INR) monitoring. Education may improve time in therapeutic range (TTR) a measure of warfarin effect, and a surrogate for patient adherence, safety and efficacy.

METHODS

The Pediatric Anticoagulation program (Stollery Children's Hospital) developed a novel child-focused educational program KIDCLOT-POC about warfarin therapy and POC-INR meter use. A total of twenty eight children, and their caregivers, participated in KIDCLOT-POC. Questionnaire score comparisons and practical demonstrations assessed the learners' theoretical and practical knowledge of warfarin management.

RESULTS

In caregivers, the median pre, post and knowledge retention questionnaire scores were 50 (IQR 27), 93 (IQR 6) (p<0.0001) and 96 (IQR 6) (p<0.0001), respectively. In the 18 children who were >or=6 years of age, post and knowledge retention questionnaire scores were 90 (IQR 16) and 92 (IQR 23) (p=0.44), respectively. The TTR for all children was 81.7% (SD 13.1).

CONCLUSIONS

Implementation of KIDCLOT-POC program appears to promote high knowledge development and retention in children and caregivers and high TTR with no adverse events.

Proteolytic cleavage of carboxypeptidase N markedly increases its antifibrinolytic activity

BACKGROUND

Carboxypeptidase N (CPN) is a constitutively active basic carboxypeptidase sharing specificity with activated thrombin-activable fibrinolysis inhibitor (TAFIa). Generally, CPN is regarded as being non-antifibrinolytic. However, this assumption has not been thoroughly investigated, particularly with respect to long-term antifibrinolysis. In addition, a recent report has shown that plasmin cleavage increases the catalytic activity of CPN. Therefore, we investigated the antifibrinolytic properties of CPN and plasmin-cleaved CPN (CPNc).

METHODS

CPN was incubated with plasmin for various periods of time and the prolongation of clot lysis at various concentrations of CPN/CPNc mixture was investigated in TAFI-depleted plasma. CPN cleavage was analyzed by electrophoresis and catalytic activity was determined by monitoring cleavage of the small substrate, FA-Ala-Lys.

RESULTS

CPN exhibited antifibrinolytic properties in plasma clot lysis assays when present at supraphysiological concentrations. Depletion of CPN from plasma decreased the lysis time of clots formed from minimally diluted plasma at low tissue-type plasminogen activator (t-PA) concentrations. Plasmin cleavage of CPN markedly increased the antifibrinolytic properties. CPN and CPNc prolonged lysis in a non-saturable, dose-dependent, and t-PA-dependent manner. At sufficient concentration, CPN and CPNc prolonged lysis at least forty-fivefold. CPNc was 700% more antifibrinolytic than CPN but only 7% more active toward FA-Ala-Lys. The active site inhibitor GEMSA eliminated the antifibrinolytic effects of CPN and CPNc. Antifibrinolytic activity correlated with cleavage of active and/or regulatory subunits, presumably generating heterodimeric CPNc.

CONCLUSIONS

Limited proteolysis of CPN by plasmin generates an enzyme with greatly increased antifibrinolytic properties. We speculate that (patho)physiological proteolysis of CPN may generate a long-term antifibrinolytic enzyme.

Specialist dermatology clinics for organ transplant recipients significantly improve compliance with photoprotection and levels of skin cancer awareness

BACKGROUND

Organ transplant recipients (OTRs) have 100-fold increased risk of developing squamous cell carcinomas. Cumulative exposure to ultraviolet radiation is the main risk factor and there is evidence that lack of dermatological surveillance may be responsible for poor levels of knowledge and photoprotection among OTRs.

OBJECTIVES

This study evaluated whether routine consultation in a specialist OTR dermatology clinic improves understanding of skin cancer risk and compliance with photoprotection measures.

METHODS

A cross-sectional questionnaire-based study was performed in a specialist OTR dermatology clinic at Bart's and the London NHS Trust, London, U.K. The subjects were 399 white-skinned patients under surveillance in a renal transplant clinic, who were sent a postal questionnaire from the renal transplant clinic. The main outcome measures were responses to the questionnaire regarding photoprotective practices and skin cancer risk awareness.

RESULTS

Two hundred and ninety-two of 399 (73%) responded, of whom 89% had previously attended the specialist dermatology clinic. Ninety-six per cent recalled receiving photoprotection advice at least once (85% from dermatologists); 92% reported use of sunscreen; 88% specifically dressed to photoprotect themselves; 96% directly avoided sun exposure during summer; 68% were aware that an increased risk of skin cancer was the reason that extra photoprotective measures were important after a transplant. Photoprotective measures and level of skin cancer awareness were significantly lower in those responders who had never attended the specialist clinic. No obvious bias was identified among nonresponders.

CONCLUSIONS

Skin cancer awareness and compliance with photoprotective measures in our patient population is generally greater than previously reported, suggesting that delivery of educational messages regarding skin cancer may be improved if provided in a specialist dermatological setting.

Manmade and natural radionuclides in north east Atlantic shelf and slope sediments: Implications for rates of sedimentary processes and for contaminant dispersion

Results are presented for a study of manmade and natural radionuclides in north east Atlantic continental shelf and slope sediments to the west of Scotland. The data are interpreted in the context of sediment mixing and accumulation processes and are used to establish the westward extent of contamination of the sediment system. Offshore shelf and slope sediments were found to have post-glacial sedimentation rates of the order of 1 cm ky(-1) but nearshore sediments had much higher accumulation rates of the order of 0.1 cm y(-1). Surface mixed layer depths of up to 6 cm were observed and non-local mixing affected most of the slope sediments, resulting in advective transport of surface sediment to depths of up to 10 cm. Biodiffusion coefficients for offshore shelf and slope sediments were dominantly in the range 10(-8) to 10(-9) cm2 s(-1). The study confirmed that seawater contaminated with Sellafield waste radionuclides is dominantly entrained to the east of 7 degrees W and, consistent with this, higher levels of Sellafield derived radionuclides were confined to nearshore sediments, with lower levels to the west of 7 degrees W. 238Pu/(239,240)Pu data indicated that Sellafield contributed 75-91% of the total plutonium in coastal sediment but only about 4-8% of the total in slope sediments. By analogy, it can be concluded that a similar situation will apply to other contaminants in seawater entering the north east Atlantic via the North Channel.

Star testing: a novel evaluation of intraocular lens optical quality

BACKGROUND

Despite the importance of optical quality of an intraocular lens (IOL) on visual outcomes following cataract surgery, objective data on their optical quality are not readily available, and manufacturing standards are industry regulated. The star test is a classic test of optical quality based on examination of the Airy disc and expanded diffraction rings of a point source of light, used mainly for telescope and microscope objectives.

METHODS

A physical model eye cell allowed star testing of IOLs under conditions similar to the optical environment in which they operate. 18 IOLs were tested and results compared to actual images produced by these lenses in the model eye cell. Quantitative measures of star testing performance were developed.

RESULTS

The optical performance of the IOLs varied, some performing very poorly. Most lenses (13/17) performed better in reverse orientation, while aberrations induced by the haptics of foldable IOLs were also detected. There was excellent correlation between actual images formed and star testing parameters.

CONCLUSION

Star testing IOLs was a novel biomedical application of a centuries old, inexpensive method. A concerning variation of optical quality was found, suggesting IOL optical performance data should be more readily available. Independent, authority mandated IOL optical quality standards should be developed, and results readily available to ophthalmologists.

The need to redefine non-cystic fibrosis bronchiectasis in childhood

BACKGROUND

Non-cystic fibrosis (CF) bronchiectasis has previously been reported to be rare and progressive in children living in western societies.

METHOD

A clinical and radiological review was undertaken of 93 children with non-CF bronchiectasis defined by high resolution computed tomographic (HRCT) scanning presenting to a tertiary paediatric respiratory centre since 1996.

RESULTS

Cases constituted 9.6% of all new referrals. Male to female ratio was 2:1. Median age at symptom onset was 1.1 years (range 0-16) and of HRCT diagnosis was 7.2 years (1.6-18.8). The most common referral diagnosis of asthma was refuted in 39 of 45 cases. Associations were previous pneumonic illness (30%), immunocompromise (21%), obliterative bronchiolitis (9%), congenital lung abnormality (5%), chronic aspiration (3%), eosinophilic oesophagitis (2%), familial syndrome (2%), primary ciliary dyskinesia (1%), and right middle lobe syndrome (1%). 8% had two associated diagnoses and 18% were idiopathic. There was agreement between the chest radiograph and HRCT scan for diagnosis and lobe affected in only five cases (5%). A repeat HRCT scan in 18 cases at a minimum interval of 18 months showed total resolution of the changes in six, improvement in one, progression in five, and was unchanged in six.

CONCLUSIONS

Radiologically defined non-CF bronchiectasis in children is not uncommon. Diagnostic delay is a problem. The most common association is a previous pneumonia. Chest radiography is of little diagnostic value, but resolution is possible on HRCT scanning. Bronchiectasis is currently defined as a condition which is both permanent and progressive. This term is not necessarily appropriate for all paediatric patients for whom we suggest an alternative nomenclature.

Lercanidipine vs lacidipine in isolated systolic hypertension

This randomised, double-blind, double-dummy, parallel group, multicentre study compared the efficacy and tolerability of lercanidipine with lacidipine. Elderly patients with isolated systolic hypertension (supine blood pressure >/=160/<95 mmHg) were enrolled and underwent a placebo run-in period of 14-27 days before random allocation to lercanidipine tablets 10 mg once daily (n=111) or lacidipine tablets 2 mg once daily (n=111) for the assessment period (112-160 days). Titration to lercanidipine 20 mg once daily (two 10 mg tablets) or lacidipine 4 mg once daily (two 2 mg tablets) was allowed after 8 weeks, if required. Both treatments decreased supine and standing systolic and diastolic blood pressure between the end of the run-in period and the end of the assessment period (P<0.0001). At the end of the assessment period, the estimated mean treatment difference (95% confidence intervals) in supine systolic blood pressure was -0.81 (-4.45, 2.84) mmHg. These confidence intervals were within the limits specified for equivalence, that is, (-5, 5) mmHg. Ambulatory blood pressure monitoring showed that the antihypertensive effects of both drugs lasted for the full 24-h dosing period and followed a circadian pattern. Both treatments were well tolerated with a low incidence of adverse drug reactions and a low withdrawal rate. Significantly fewer patients withdrew from treatment with lercanidipine (P=0.015). Neither treatment had any clinically significant effect on pulse rate or cardiac conduction. In conclusion, both treatments were equally effective in controlling supine systolic blood pressure in patients with isolated systolic hypertension.

Do Thoroughbred and Standardbred horses have similar increases in pulmonary vascular pressures during exertion?

To test the hypothesis that the pulmonary vascular pressures of Thoroughbred and Standardbred horses behave similarly during exertion. Measurements were made on 5 Thoroughbred and 5 Standardbred horses on a treadmill at rest and during 3-minute exercise intervals at speeds predicted to produce 75%, 90%, and 100% maximal heart rate. Left forelimb acceleration, heart rate, esophageal pressure, and pulmonary artery pressure were measured continuously. Pulmonary capillary and wedge pressures were measured during intermittent occlusion of the pulmonary artery. Breathing rate and gait frequency were the fundamental frequencies of the esophageal pressure and limb acceleration signals respectively. The ratio of speed:gait frequency gave stride length. The effects of exertion and breed were evaluated using two-way analysis of variance. Exertion produced significant increases in pulmonary artery (P = 0.001), capillary (P = 0.002), and wedge (P = 0.005) pressures. No significant effect of breed was detected on pulmonary artery pressure, but at exertion pulmonary capillary and wedge pressures were 15% (P = 0.03) and 23% (P = 0.04) greater in Thoroughbreds, respectively. Treadmill speed was approximately 12% greater (P = 0.04), stride length was approximately 25% greater (P = 0.0003), gait frequency was approximately 10% less (P = 0.006), breathing rate was approximately 10% less (P = 0.001), and heart rate was approximately 6% less (P = 0.06) for Thoroughbreds. There was no effect of breed on inspiratory or expiratory esophageal pressure although mean esophageal pressure was approximately 2 mmHg greater (P = 0.03) in exercising Standardbreds. In conclusion, pulmonary capillary and wedge pressures are greater in Thoroughbreds than in Standardbreds at similar fractions of maximal heart rate. This is compatible with the higher incidence of exercise-induced pulmonary hemorrhage observed in Thoroughbreds.

Hepatic and intestinal cytochrome P450 and conjugase activities in rats treated with black tea theafulvins and theaflavins

Theaflavins and theafulvins, a fraction of thearubigins, were isolated from aqueous infusions of black tea, and their effects on the hepatic and intestinal cytochrome P450 system, and on the glutathione S-transferase, epoxide hydrolase, glucuronosyl transferase and sulphotransferase enzyme systems were investigated in rats following oral intake for four weeks. Neither theafulvins nor theaflavins influenced cytochrome P450 activity in the liver as exemplified by the O-dealkylations of methoxy-, ethoxy- and pentoxyresorufin, the hydroxylations of lauric acid and p-nitrophenol, and the N-demethylation of erythromycin; similarly, hepatic xenobiotic conjugation systems were unaffected. In the intestine, both polyphenolic fractions markedly suppressed the O-deethylation of ethoxyresorufin and this was accompanied by a decrease in the CYP1A1 apoprotein levels. Probing intestinal microsomes with antibodies to CYP2E1 revealed the presence of a single band in the cytochrome P450 region whose intensity was lower in the polyphenol-treated animals. Immunoblot analysis utilising antibodies to CYP3A showed that the treatment with theafulvins and theaflavins reduced the apoprotein levels. A single band in the cytochrome P450 region was evident when the intestinal microsomes were probed with antibodies to CYP4A1 but the level of expression was not affected by the treatment with the black tea polyphenols. Finally, treatment of the rats with theaflavins had no effect on any of the intestinal conjugating enzymes studied, but treatment with theafulvins led to inhibition of glucuronosyl transferase activity.

Clinical and electrophysiological differences between patients with arrhythmogenic right ventricular dysplasia and right ventricular outflow tract tachycardia

AIMS

Radiofrequency catheter ablation is considered first line treatment for symptomatic patients with right ventricular outflow tract tachycardia (RVOT). The role of ablation in arrhythmogenic right ventricular dysplasia (ARVD) is more limited. As such, differentiating between the two conditions is essential.

METHODS AND RESULTS

This study compared non-invasive findings, magnetic resonance images (MRI), invasive electrophysiological characteristics, results of ablation and long-term outcome in 50 consecutive patients with RVOT (33) or ARVD (17). Structural abnormalities were uniform in the ARVD group; in addition 18 (54%) of the RVOT tachycardia group had MRI abnormalities. At electrophysiological study the tachycardia in the ARVD group displayed features of re-entry in over 80%, but behaved with a triggered automatic basis in 97% with RVOT. Ablation was complete or partial success in 12 (71%) patients with ARVD and ventricular tachycardia (VT) recurred in eight (48%). In the RVOT patients, ablation was a complete success in 97% with recurrent VT in 6%. Long-term success in the RVOT patients was 95% in both patients with and without MRI abnormalities.

CONCLUSIONS

Electrophysiological characterization can differentiate ARVD from RVOT. The finding of abnormalities on MRI does not have any bearing on arrhythmia mechanism, acute or long-term success of RFA.

The effect of ReTain plant growth regulator [aminoethoxyvinylglycine (AVG)] on the postharvest storage life of 'Tegan Blue' plums

ReTain plant growth regulator is a commercial formulation of aminoethoxyvinylglycine (AVG). This compound is known to competitively inhibit the activity of the enzyme ACC (1-aminocyclopropanecarboxylate) synthase which is the rate limiting enzyme in the ethylene biosynthesis pathway. By inhibiting the activity of ACC synthase, ethylene-mediated ripening processes can be delayed.'Tegan Blue' plums have low ethylene production, which indicates that it is a suppressed climacteric variety. There was a significant difference between the ReTain treated and untreated fruit for the second harvest, this difference was greater later in storage than early in storage. The results indicate that there is a postharvest benefit achieved after applying AVG to 'Tegan Blue' plums. The main advantage is in the maintenance of firmness for late-harvested fruit. Other benefits are the suppression of ethylene production and the development of a more intense colour.

A randomized controlled trial to investigate brackets bonded with a hydrophilic primer

OBJECTIVE

To compare the clinical failure rates of brackets bonded using a prototype hydrophilic primer, designed to be insensitive to moisture, with brackets bonded with a conventional primer.

DESIGN

Single centre randomised controlled clinical study. Thirty-three patients were bonded using a split mouth technique: randomly allocating the hydrophilic primer to one side of the mouth and a conventional primer to the other.

SETTING

Hospital orthodontic department, Bradford, UK.

SUBJECTS

Orthodontic patients requiring fixed appliances.

MAIN OUTCOME MEASURES

The site and time to bond failure was recorded for each bracket that failed over 6 months.

RESULTS

Using survival analysis, there was an increased risk of bracket failure when bonded with the hydrophilic primer compared with the conventional primer (hazard ratio = 2.2, 95% confidence interval: 1.1 to 4.5, P = 0.01).

CONCLUSIONS

This hydrophilic primer cannot be recommended for routine clinical use.

Behçet's disease complicated by pylephlebitis and hepatic abscesses

A 22 year old man presented with fever, abdominal pain, weight loss and diarrhea. Past medical history revealed recurrent aseptic meningitis, uveitis, and erythema nodosum. Further inquiry unveiled a prominent history of oral aphthous ulcers; all features of Behçet's disease. Imaging revealed mesenteric arteritis and pylephlebitis, septic thrombophlebitis of the portal vein, a previously unrecognized complication of Behçet's disease, with multiple intrahepatic abscesses. Portal venography demonstrated an extensively diseased, expanded, and obstructed portal venous system. Blood cultures and portal vein aspirate yielded polymicrobial flora. Percutaneous intraportal thrombolytic therapy and mechanical thrombectomy were attempted to restore flow to the portal venous system. This distinctly rare manifestation of Behçet's Disease, pylephlebitis, may result from ischemic injury and structural compromise of the bowel mucosa, resulting from underlying vasculitis.

Fluoride-releasing elastomeric modules reduce decalcification: a randomized controlled trial

OBJECTIVE

To determine whether fluoride releasing elastomeric modules reduced the incidence of decalcification around orthodontic brackets during a complete course of orthodontic treatment.

DESIGN

A randomised controlled, split mouth design.

SETTING

The study was carried out in the orthodontic department of Newcastle-upon-Tyne Dental Hospital, UK.

SUBJECT AND METHODS

21 consecutive patients (126 teeth) undergoing fixed appliance therapy were studied. A split mouth technique was adopted to examine the upper labial segment, where one side (left or right) was randomly assigned to the experimental group, and the opposite side served as a control throughout their course of orthodontic treatment.

INTERVENTIONS

The control teeth were ligated to the archwire using conventional modules. The experimental teeth were ligated to the archwire using Fluoride releasing elastomeric modules.

OUTCOME MEASURES

Standardised photographs were taken of the upper labial segment before and after completion of orthodontic treatment, and the degree of decalcification assessed in each tooth quadrant, using a modification of the Enamel Defect Score.

RESULTS

Decalcification was found to occur in both treatment groups, though to a significantly greater degree on the control side (p = 0.002). The fluoride module side showed significantly fewer serious decalcified lesions than the control (p = 0.013). No patients withdrew from the study.

CONCLUSIONS

It would appear that the use of fluoride releasing elastomeric modules reduces the degree of decalcification experienced during orthodontic treatment.

Characterization of the active sites in decay-accelerating factor

Decay-accelerating factor (DAF) is a complement regulator that dissociates autologous C3 convertases, which assemble on self cell surfaces. Its activity resides in the last three of its four complement control protein repeats (CCP2-4). Previous modeling on the nuclear magnetic resonance structure of CCP15-16 in the serum C3 convertase regulator factor H proposed a positively charged surface area on CCP2 extending into CCP3, and hydrophobic moieties between CCPs 2 and 3 as being primary convertase-interactive sites. To map the residues providing for the activity of DAF, we analyzed the functions of 31 primarily alanine substitution mutants based in part on this model. Replacing R69, R96, R100, and K127 in the positively charged CCP2-3 groove or hydrophobic F148 and L171 in CCP3 markedly impaired the function of DAF in both activation pathways. Significantly, mutations of K126 and F169 and of R206 and R212 in downstream CCP4 selectively reduced alternative pathway activity without affecting classical pathway activity. Rhesus macaque DAF has all the above human critical residues except for F169, which is an L, and its CCPs exhibited full activity against the human classical pathway C3 convertase. The recombinants whose function was preferentially impaired against the alternative pathway C3bBb compared with the classical pathway C4b2a were tested in classical pathway C5 convertase (C4b2a3b) assays. The effects on C4b2a and C4b2a3b were comparable, indicating that DAF functions similarly on the two enzymes. When CCP2-3 of DAF were oriented according to the crystal structure of CCP1-2 of membrane cofactor protein, the essential residues formed a contiguous region, suggesting a similar spatial relationship.

MRI changes in multiple sclerosis following treatment with lofepramine and L-phenylalanine

As part of a large, randomized placebo-controlled trial of inpatients with multiple sclerosis (MS), a subsample of 15 underwent cerebral MRI at baseline and 6-months (eight on lofepramine and l-phenylalanine; seven on placebo). Unlike the placebo group, the active group showed a significant reduction in lesion number visible on T1-weighted scans (p < 0.05). The lateral ventricular volume increased, on average, by 1020 mm3 in the untreated group and 600 mm3 in the treated group. In the treated patients the ventricular size change correlated with both change in Gulick MS-related symptoms scale scores (rs = 0.71, p = 0.07) and Gulick MS-related activities of daily living scale scores (rs = -0.83, p = 0.02). It is concluded that treatment with lofepramine and l-phenylalanine is associated with significant MRI changes.

Development and application of a quantitative, specific assay for Cryptosporidium parvum oocyst detection in high-turbidity environmental water samples

Chlorine-resistant Cryptosporidium parvum oocysts in drinking water play an important role in the epidemiology of cryptosporidiosis. Current methods of detecting these organisms in water are insensitive, labor-intensive, highly subjective, and severely limited by sample turbidity. We describe here an alternative technique utilizing electrochemiluminescence (ECL) technology for detecting C. parvum oocysts in environmental water samples. This method is quantitative, reproducible, and requires only minimal sample processing. Currently, the ECL assay can detect as few as one oocyst in one milliliter of concentrated test sample with sample turbidity of up to 10,000 nephelometric turbidity units. Water and sewer samples collected during a cryptosporidiosis outbreak were tested by ECL assay. Cryptosporidium parvum oocysts were found in the source water at the time of outbreak, and a sharply decreasing level of oocysts in sewer samples was observed over a three-month period following the outbreak.

Early and periodic screening, diagnosis, and treatment examination completion rates for Oklahoma Medicaid managed care: 1995-1998

Although quality medical care is a goal of all health care providers, finding a means by which to take that idea from the abstract to the measurable is often an arduous task. The Oklahoma Health Care Authority and the Oklahoma Foundation for Medical Quality confronted that challenge when examining the state of Oklahoma's Early and Periodic Screening, Diagnosis, and Treatment (EPSDT) examination completion rates. Focused on measuring processes of care, the Oklahoma Health Care Authority (OHCA) and the Oklahoma Foundation for Medical Quality (OFMQ) used chart abstraction to track EPSDT examination rates for SoonerCare Plus Medicaid managed care recipients from 1995 through 1998. During the abstractions, an examination was interpreted as an EPSDT screen if a comprehensive health and development history plus a comprehensive unclothed physical examination were recorded. Examination rates have improved from 1995 when there was a documented 17.6% completion rate. The 1998 documented rate of completion was 60.0%. Trend analysis shows significant improvement over the four-year period. The results also suggest the necessity for continued improvement in the provision of documented EPSDT examinations to individuals in Medicaid managed care plans in Oklahoma.