Scanning electron-microscopic study of pellicle and plaque formation on tetracyclineimpregnated dentin

Abstract — Previous experiments have shown that tetracyclinecs may react with hydrosyapatite, e.g. in enamel and dentin, without losing their antimicrobial capacity. The present paper examines the pattern of pellicle and plaque formation on doxycycline-treated dentin by the use of scanning electron microscopy (SEM). From newly extracted human teeth were prepared standardized dentin slabs, half of which were soaked in aqueous solutions of doxycycline HC1, 10 mg/ml (pH 2.5) for 10 min. Seven volunteers carried doxycycline-impregnated specimens ligated to the buccal surface of a maxillary molar for 2 h, 8 h, 24 h and 120 h, respectively. Untreated control specimens were ligated to the contralateral teeth. After removal from the oral cavity, the dentin slabs were briefly rinsed in water, allowed to air dry and processed for SEM. SEM assessment of the specimens showed that doxycycline-impregnation resulted in a superficial etching of the dentin, a reduced rate of pellicle formation as well as an impairment of pellicle adhesion, and a retarded bacterial plaque formation on the dentin surfaces.     

Aetiology of Acute Pharyngitis and Clinical Response to Empirical Therapy with Erythromycin Versus Amoxicillin

Guthrie R M, Ruoff G E, Rofman BA, Ginsberg D, Karp R R, BrownS M and Schulz GA. Aetiology of acute pharyngitis and clinicalresponse to empirical therapy with erythromycin versus amoxicillin.Family Practice 1988; 5: 29–35. One hundred and eighty-nine adults with acute pharyngitis hadculture and serological evaluation for groupA beta haemolyticstreptococci (GABHS), Mycoplasma pneumoniae, and Branhamellacatarrhalis. Sixteen patients had evidence for infection withGABHS, none for M. pneumoniae, and one for B. catarrhalis. Forthose with GABHS, there was no significant difference betweenempirical treatment by erythromycin or amoxicillin. For thosewithout GABHS, empirical treatment with erythromycin appearedto result in a statistically significant reduction in coughand a noticeable but less than significant reduction of othersymptoms when compared to empirical treatment with amoxicillin.The new formula tion of erythromycin utilized in this study(PCE) may be associated with a reduction in gastrointestinalintolerance from that reported with other erythromycin products.     

A Group-Based Training Programme for General Practitioners: A Norwegian Experience

Westin S, stensen A I, Lvslett K, Prytz J, Telje J, TelstadW and Lie A. A group-based training programme for general practitioners:a Norwegian experience. Family Practice 1988; 5: 244–252. There are approximately 3000 general practitioners in Norway,serving a population of slightly above four million people.A three year postgraduate education scheme for general practitionershas been in effect since 1973, to be replaced by a five yearvocational training programme from January 1985, making generalpractice a fully recognized specialty from that date. The educationalrequirements consist of one year of hospital training, fouryears of training in general practice, and a total of 400 hoursof course education, mainly in clinical subjects. The core elementof the training is attendance at a group-based structured educationalprogramme of two years' duration. This article describes theconcepts and content of this decentralized group-based education,as well as some of the conflicting considerations which eventuallyled to this new Norwegian model of general practice training.The first evaluation studies indicate that the educational programmehas met a long standing need among general practitioners.     

Outcomes in total elbow arthroplasty in patients with haemophilia at the University of California,San Francisco: a retrospective review

Summary. Severe haemophilic arthropathy of the elbow is a significant cause of morbidity among adults with haemophilia. However, previous reports of total elbow arthroplasty (TEA) in the haemophilic population have been based on small numbers of patients with relatively short‐term follow‐up. The records of seven total elbow arthroplasties in six adult men with haemophilia at the University of California, San Francisco who underwent TEA over a period of 25 years were retrospectively reviewed. Type of haemophilia, age at time of TEA, HIV infection status, pre‐ and postoperative range‐of‐motion (ROM) scores, complications (including infections), need for subsequent surgical revision and functional outcomes were recorded. Four patients had severe factor VIII deficiency and two patients had severe factor IX deficiency. None of the patients had an inhibitor. The mean age at the time of surgery was 34 years (range, 22–46 years) and the mean follow‐up period was 118 months (range, 37–176 months). One of the six patients had TEA in both elbows. Five of the six patients were infected with HIV. There were no immediate perioperative complications. At a mean of 19.2 months postoperatively, ROM had improved in five of seven TEAs: mean flexion had increased from 110.7° (SD = 15.0) to 120.1° (SD = 14.5), whereas mean preoperative extension increased from ?44.3° (SD = 21.5) to ?36.9° (SD = 27.0). One patient required a revision at 30 months because of ulnar component loosening. This same patient sustained a staph epidermidis infection and ultimate removal of the prosthesis 15 years postoperatively. At a mean of 118 months postoperatively, five of six patients continued to report reduced pain and preserved functionality, with ability to perform normal daily activities. TEA resulted in favourable results in six of seven procedures. Our findings support the viability of TEA for individuals with severe haemophilic arthropathy of the elbow, especially to reduce pain and preserve or restore functionality. Level of evidence .  Level IV.     

Hematin and Bilirubin Binding to Human Serum Albumin and Newborn Serum

ABSTRACT. In jaundiced newborn infants, hemolytic disease is considered a risk factor for kernicterus due to the suspected competition between bilirubin and other hemoglobin breakdown products for albumin binding. We have studied the effect of hematin on bilirubin-albumin binding using the peroxidase assay and a light-scattering technique for measuring unbound bilirubin. Our results show that hematin does not affect bilirubin-albumin binding. To determine if other albumin binding functions are affected by hematin, we used a microdialysis rate technique employing two ligands, diazepam and monoacetyldiaminodiphenyl sulfone (MADDS). Hematin does not utilize the diazepam binding function of albumin, but does decrease the albumin binding of MADDS. The results of this study indicate that the MADDS and bilirubin binding functions are not identical. The clinical usefulness of reserve albumin equivalent determination using MADDS is discussed.     

Enhanced Predictive Power of Quantitative TWA during Routine Exercise Testing in the Finnish Cardiovascular Study

Introduction: We examined whether quantification of T-wave alternans (TWA) enhances this parameter's capacity to evaluate the risk for total and cardiovascular mortality and sudden cardiac death (SCD).
Methods and Results: The Finnish Cardiovascular Study (FINCAVAS) enrolled consecutive patients (n = 2,119; 1,342 men and 777 women) with a clinically indicated exercise test with bicycle ergometer. TWA (time domain-modified moving average method) was analyzed from precordial leads, and the results were grouped in increments of 10 μV. Hazard ratios (HR) for total and cardiovascular mortality and SCD were estimated for preexercise, routine exercise, and postexercise stages. Cox regression analysis was performed. During follow-up of 47.1 ± 12.9 months (mean ± standard deviation [SD]), 126 patients died: 62 were cardiovascular deaths, and 33 of these deaths were sudden. During preexercise, TWA ≥ 20 μV predicted the risk for total and cardiovascular mortality (maximum HR >4.4 at 60 μV, P < 0.02 for both). During exercise, HRs of total and cardiovascular mortality were significant when TWA measured ≥50 μV, with 90 μV TWA yielding maximum HRs for total and cardiovascular death of 3.1 (P = 0.03) and 6.4 (P = 0.002), respectively. During postexercise, TWA ≥60 μV indicated risk for total and cardiovascular mortality, with maximum HR of 3.4 at 70 μV (P = 0.01) for cardiovascular mortality. SCD was strongly predicted by TWA levels ≥60 μV during exercise, with maximum HR of 4.6 at 60 μV (P = 0.002), but was not predicted during pre- or postexercise.
Conclusion: Quantification of TWA enhances its capacity for determination of the risk for total and cardiovascular mortality and SCD in low-risk populations. Its prognostic power is superior during exercise compared to preexercise or postexercise.     

Myopotential Inhibition of Unipolar QRS-inhibited (VVI) Pacemakers, Assessed by Ambulatory Holter Monitoring of the Electrocardiogram

Seventy-four patients with unipolar QRS-inhibited pacemakers (VVI) were Holter monitored to assess the occurrence of pacemaker inhibition caused by skeletal muscle potentials during daily activities. Fifty patients had high-grade atrioventricular block and 24 had sinoatrial disease. Chest wall stimulation prior to monitoring revealed asystole of > 4 seconds duration in 22 patients, and ventricular rates between 25 and 56 beats per minute in 52 patients. Fifty-one patients (69%) had one or more episodes of pacemaker inhibition from myopotentials. Inhibition occurred in all types of pacemakers studies, but was most frequent and of longest duration in patients with Siemens-Elema 207/70 (13/14 patients), Cordis Omni-Stanicor (6/7 patients), CPI Microlith (5/6 patients), and Medtronic 5945 (8/10 patients). This was not unexpected considering the filter characteristics of the pacemakers. Nine patients (12%) presented symptoms which might be ascribed to pacemaker inhibition. The longest asystole observed was 3.2 s. Seven patients had pacemakers spikes falling on or near T-waves of spontaneous heart beats because their pacemakers had been rendered refractory by myopotentials. No serious arrhythmias were seen during episodes of pacemaker inhibition or interference. More emphasis should be put on the improvement of filter characteristics of unipolar VVI-pacemakers. Pacemaker patients with symptoms of myopotential inhibition should be equipped with either a bipolar or ventricular triggered (VVT) pacemaker or with a sensitivity and/or pacing mode programmable pacemaker.