In-circuit high-frequency jet ventilation to reduce organ motion in a child undergoing sarcoma ablation

Patients with primary or metastatic solid tumours can be treated with minimally invasive image-guided procedures as an alternative to surgical resection. Reducing organ motion during these procedures is crucial so that tumours can be accurately targeted and treatment delivered within a small margin, limiting potential damage to adjacent structures. As ventilation is the main cause of motion, there has been a shift from conventional ventilation towards the use of in-circuit high-frequency jet ventilation techniques for these procedures. We present the case of a 7-year-old who required computed tomography-guided microwave ablation of a right lung metastatic nodule under general anaesthesia. The patient's lungs were ventilated with in-circuit high-frequency jet ventilation in order to provide optimum conditions for ablation. The treatment was successfully completed and she was discharged home the following day. High-frequency jet ventilation is regularly used in our institution for adult computed tomography-guided treatments and to our knowledge, this application has not been described yet in a child this young. Our experience suggests that this technique can be safely used in paediatric patients, though further investigation of the optimum parameters for in-circuit high-frequency jet ventilation in this population is warranted.

OP0060 MACHINE LEARNING BASED BERLIN SCORING OF MAGNETIC RESONANCE IMAGES OF THE SPINE IN PATIENTS WITH ANKYLOSING SPONDYLITIS FROM THE MEASURE 1 STUDY

Background:

Magnetic resonance imaging (MRI) offers a non-invasive and objective method of early diagnosis and classification, monitoring disease burden and treatment response for patients (pts) with axial spondyloarthritis (axSpA) including ankylosing spondylitis (AS).1Numerous scoring schemes such as the AS Spine MRI Activity (ASspiMRIa) score are available for the quantitative assessment of MRI, but are subject to intra- and inter-rater variability, labor intensive and costly. Nevertheless, quantification of MRI changes has become an important tool to demonstrate treatment success of biologic drugs in axSpA.

Objectives:

To evaluate the performance of machine learning (ML) based software for automated Berlin grading of spinal MRI bone marrow oedema in pts with AS and compare with expert scoring.

Methods:

Fully automated ML software (Figure) was developed to detect and label 23 vertebrae, define vertebral units (VU) as per the Berlin modification of the ASspiMRIa score, and score each VU as either 0 (score of 0) or 1 (score of 1, 2 or 3). The ML algorithm was based on the previously developed SpineNet software.2Analysis included 108 pts from the secukinumab MEASURE 1 study3, in which imaging was done using T1 and STIR sagittal MRI at baseline and Weeks 16, 52, 104, 156 and 208. Two expert readers, blinded to treatment and visit, evaluated all images by ASspiMRIa score. The scores from Reader 2 (R2) were binned into two groups: 0 vs 1, 2, or 3. As a result of multiple pt time points and expert reading sessions, the complete dataset comprised of 10,988 VU. Ten-way cross-validation at per-VU was used to train and validate the ML software. The dataset was split into 10 randomly selected subsets, ensuring that each pt appears in only one subset, after which 8 subsets were used for training the ML software, 1 was used to check for correct training and 1 was used for validation. The process was repeated ten times such that all 10 subsets were used for validation. Accuracy weighted for the frequency of each category, sensitivity and specificity were calculated using scores from R2 as reference. Intra-reader accuracy was also calculated.

Results:

Accuracy of the software in relation to expert reader scores was 67% with a sensitivity of 0.63 and specificity of 0.70. The intra-reader accuracy was 71% and 77% for R1 and R2, respectively. Individual VU scoring of the Software vs. R2 are presented in the Table as a confusion matrix.

Conclusion:

Automated scoring of MR images in AS pts provided moderate agreement to that of expert reader-based assessments. ML software has potential to provide an automated guided-reading approach to scoring MR images, which may enable further clinical insights.

References:

[1]Lukas C, et al. J Rheumatol. 2007;34:862-70.

[2]Jamaludin A, et al. Eur Spine J. 2017;26:1374-83.

[3]Baeten D, et al. N Engl J Med. 2015;373,2534-48.

Figure.

Processing pipeline of automated Berlin scoring software

Table.

Confusion matrix between the software and R2

SoftwareScore = 0SoftwareScore = 1, 2 or 3Total VU scoredR2 Score = 07199 (70%)3068 (30%)10,267R2 Score = 1, 2 or 3251 (35%)475 (65%)7267,4503,54310,993

Percentages calculated as a fraction over the total in each row. Overall accuracy is the average of the highlighted percentages.

Disclosure of Interests:

Amir Jamaludin: None declared, Rhydian Windsor: None declared, Sarim Ather: None declared, Timor Kadir: None declared, Andrew Zisserman: None declared, Juergen Braun Grant/research support from: Abbvie (Abbott), Amgen, BMS, Boehringer, Celgene, Celltrion, Centocor, Chugai, Eli Lilly and Company, Medac, MSD (Schering Plough), Mundipharma, Novartis, Pfizer (Wyeth), Roche, Sanofi- Aventis, and UCB Pharma, Consultant of: Abbvie (Abbott), Amgen, BMS, Boehringer, Celgene, Celltrion, Centocor, Chugai, EBEWE Pharma, Eli Lilly and Company, Medac, MSD (Schering-Plough), Mundipharma, Novartis, Pfizer (Wyeth), Roche, Sanofi-Aventis, and UCB Pharma, Speakers bureau: Abbvie (Abbott), Amgen, BMS, Boehringer, Celgene, Celltrion, Centocor, Chugai, EBEWE Pharma, Eli Lilly and Company, Medac, MSD (Schering-Plough), Mundipharma, Novartis, Pfizer (Wyeth), Roche, Sanofi-Aventis, and UCB Pharma, Lianne S. Gensler Grant/research support from: Pfizer, Novartis, UCB, Consultant of: AbbVie, Eli Lilly, GSK, Novartis, UCB, Pedro Machado Consultant of: Abbvie, Celgene, Janssen, Lilly, MSD, BMS, Novartis, Pfizer, Roche and UCB, Speakers bureau: AbbVie, Centocor, Eli Lilly, Janssen, MSD, Novartis, Pfizer and UCB Pharma, Mikkel Ǿstergaard Grant/research support from: AbbVie, Bristol-Myers Squibb, Celgene, Merck, and Novartis, Consultant of: AbbVie, Bristol-Myers Squibb, Boehringer Ingelheim, Celgene, Eli Lilly, Hospira, Janssen, Merck, Novartis, Novo Nordisk, Orion, Pfizer, Regeneron, Roche, Sandoz, Sanofi, and UCB, Speakers bureau: AbbVie, Bristol-Myers Squibb, Boehringer Ingelheim, Celgene, Eli Lilly, Hospira, Janssen, Merck, Novartis, Novo Nordisk, Orion, Pfizer, Regeneron, Roche, Sandoz, Sanofi, and UCB, Denis Poddubnyy Grant/research support from: AbbVie, MSD, Novartis, and Pfizer, Consultant of: AbbVie, Bristol-Myers Squibb, Eli Lilly, MSD, Novartis, Pfizer, Roche, UCB, Speakers bureau: AbbVie, Bristol-Myers Squibb, Eli Lilly, MSD, Novartis, Pfizer, Roche, UCB, Thibaud Coroller Shareholder of: Novartis, Employee of: Novartis, Brian Porter Shareholder of: Novartis, Employee of: Novartis, Shephard Mpofu Shareholder of: Novartis, Employee of: Novartis, Aimee Readie Shareholder of: Novartis, Employee of: Novartis

Percutaneous neuromodulation pain therapy following knee replacement

A new device (Deepwave) utilizing percutaneous neuromodulation technology has been developed with preliminary studies demonstrating superior pain inhibition compared with transcutaneous electrical nerve stimulation. We hypothesize that the use of Deepwave is efficacious in reducing the severity of acute pain and opioid use in patients following total knee replacement (TKR) surgery. We conducted a randomized controlled trial on 23 patients who underwent primary TKR. The patients were categorized into two groups--experimental or control group. Following TKR, patients underwent either Deepwave or sham treatments. A Brief Pain Inventory questionnaire and the amount of all pain medications taken were recorded. There was a significant reduction in patient's subjective rating of pain and Visual Analog Scale score in the experimental group (p < 0.05), with a trend toward decreased opioid use but this was not significant (p = 0.09) The Deepwave device is effective in reducing the subjective measures of pain with a trend toward decreased opioid use in patients following TKR.

Recommendations of the OARSI FDA Osteoarthritis Devices Working Group

Osteoarthritis (OA) is the most common type of arthritis and a major cause of chronic musculoskeletal pain and functional disability. While both pharmacologic and non-pharmacologic modalities are recommended in the management of OA, when patients with hip or knee OA do not obtain adequate pain relief and/or functional improvement, joint replacement surgery or other surgical interventions should be considered. Total joint arthroplasties are reliable and cost-effective treatments for patients with significant OA of the hip and knee. Evidence from cohort and observational studies has confirmed substantial improvements in pain relief with cumulative revision rates at 10 years following total hip (THA) and total knee arthroplasties (TKA) at 7% and 10%, respectively. Joint replacements have been used in most every synovial joint, although results for joints other than hip and knee replacement have not been as successful. The evolution of new device designs and surgical techniques highlights the need to better understand the risk to benefit ratio for different joint replacements and to identify the appropriate methodology for evaluating the efficacy and optimal outcomes of these new devices, designed to treat OA joints.

Stemmed implants improve stability in augmented constrained condylar knees

We previously combined experimental and computational measures to ascertain whether tibial stem augmentation reduces bone strains beneath constrained condylar implants. Using these same integrated approaches, we examined the benefit of a stem when a wedge is used. Implants were removed from the eight paired cadaver specimens from our previous experiment, and oblique defects created that were restored with 15 degrees metallic wedges cemented in place. We applied a varus moment and an axial load and monitored relative motion between implant and bone. Specimen-specific 3-D finite element models were constructed from CT scans and radiographs to examine bone stress in the proximal tibia. Implants with a wedge but no stem had greater motion than the previous control with no stem or wedge. Use of a modular stem with a wedge maintained the same level of motion as the primary case, suggesting that a stem is preferable when a wedge is utilized. The computational models confirmed this conclusion with a 30% reduction in bone stress compared to 17% in the primary case without a wedge. The wedge carried more axial load compared to the primary implant due to its support on stiff metaphyseal bone.

PFC knee replacement: osteolytic failures from extreme polyethylene degradation

Despite the long-term success of press-fit condylar (PFC) knee prostheses, premature failures caused by aggressive rapid osteolysis have been reported. To investigate why patients experience such failures, we reviewed 48 retrieved implants and surrounding tissues together with demographic and radiographic data. Polyethylene degradation was determined from density profiles taken through the retrieved inserts. We compared the histology of tissues around PFC implants with that from around failed implants of similar designs from patients matched to length of implantation, body mass index, and age. The pathologic response in PFC patients showed more widespread, dense, sheet-like cellular infiltrate, whereas in the matched patients, the infiltrate was generally scattered discontinuously. The dominant wear mode of the PFC inserts was severe delamination on the articular surfaces. Wear damage was worse with increased length of implantation and was correlated with oxidative degradation and osteolysis. Degradation and osteolysis were more severe with inserts stored longer and sterilized by gamma radiation in air. These results underscore that degradation and increased shelf life lead to osteolysis and loosening. However, they raise questions concerning the cellular reaction to the debris from PFC implants that could lead to a better general understanding of osteolysis.

Cancellous bone strains indicate efficacy of stem augmentation in constrained condylar knees

Modular augmented stems of a constrained condylar knee implant are intended to improve tibial fixation under increased varus/valgus loads, but conflicting studies have not yet indicated the factors determining stem usage and performance. To address this, we combined a paired-tibiae, cadaveric experiment of unstemmed and stemmed tibial components with specimen-specific computational models. We hypothesized that the stem would improve implant stability by decreasing implant motion and compressive strains in the proximal cancellous bone due to load transfer by the stem. The models also would indicate the important factors governing stem performance. Large variations of the displacements arose because of loading and biologic variability indicating the inconclusive effects of a stem. Despite these variations, the models showed that a stem augment consistently decreased the strains (30%-50%) in the bone beneath the tray. In tibiae of sufficient stiffness, the supporting cancellous bone did not approach yield, suggesting that a stem augment may not always be necessary. On the other hand, tibial specimens with reduced bone quality and lower stiffness benefited from a stem augment that transferred load to the distal cortical bone. Therefore, patient selection and proper sizing of the implant were identified as important factors in the analyses.

Total knee arthroplasty after varus osteotomy of the distal part of the femur

BACKGROUND

There is little information in the literature regarding the outcome of total knee arthroplasty following distal femoral varus osteotomy. The purpose of the present study was to evaluate the intermediate-term results of total knee arthroplasty following distal femoral varus osteotomy.

METHODS

The study group consisted of nine consecutive patients (eleven knees) who had had a total knee arthroplasty following varus osteotomy of the distal part of the femur. The average age of the patients was forty-four years (range, fifteen to seventy years) at the time of the arthroplasty. The results were evaluated with use of the Knee Society score preoperatively and after a mean duration of follow-up of 5.1 years. Radiographs made preoperatively and at the time of follow-up were evaluated for alignment in the coronal plane.

RESULTS

The mean Knee Society knee score was 35 points before the arthroplasty and 84 points after the arthroplasty. The mean Knee Society function score was 49 points before the arthroplasty and 68 points after the arthroplasty. The mean interval between the femoral osteotomy and the total knee replacement was fourteen years (range, two to thirty-two years). A constrained prosthesis was required in five of the eleven knees. Two knees had an excellent result, five had a good result, and four had a fair result. The mean arc of motion improved from 81.8 degrees to 105.9 degrees. The mean radiographic alignment was 3.6 degrees of valgus (range, 7 degrees of varus to 18 degrees of valgus) before the arthroplasty and 3.3 degrees of valgus (range, 1 degrees of valgus to 6 degrees of valgus) at the time of the latest follow-up. There were no infections or wound complications.

CONCLUSION

Total knee arthroplasty following distal femoral varus osteotomy decreases pain and improves knee function, but the procedure is technically demanding and is associated with inferior results when compared with those of primary arthroplasty performed in a patient without a prior femoral osteotomy. In the present series, the use of an intramedullary femoral alignment guide increased the tendency to place the femoral component in relative varus angulation (that is, in <5 degrees of valgus). We recommend checking the alignment of the femoral component with an extramedullary guide in knees that have had a previous distal femoral varus osteotomy.

The Knee Society Index of Severity for failed total knee arthroplasty: practical application

Previous classifications of severity for total knee arthroplasty revisions have been based largely on bone loss of the femur and tibia. These approaches failed to address the more technically difficult issues in revision surgery such as surgical exposure, contractures, extremity alignment, implant removal, soft tissue stability (in the anteroposterior and in the sagittal planes), extensor mechanism integrity, and patellar revisability. Through the Knee Society, the authors developed a severity index that incorporated these latter factors into one measure. The current authors describe the application of the Knee Society Index of Severity for failed total knee arthroplasty and its method of scoring.

The Knee Society Index of Severity for failed total knee arthroplasty: development and validation

Compared with primary knee replacement, total knee arthroplasty revision surgery is a more complex procedure and accounts for greater expenditures of healthcare resources at each clinical stage. Overall, patients having revision procedures have poorer functional outcomes and higher complication rates than patients having primary arthroplasty. Despite the expanded scope of revision problems and the rapidly emerging technology in revision surgery, the long-term success of any method remains in question. Because there is little consensus on the timing of revision surgery, optimal surgical reconstruction, and the type of prosthesis to be implanted, the Knee Society began development of an Index of Severity for Failed Total Knee Arthroplasty. Fifty-four percent of Knee Society members completed an 82-item questionnaire that determined their clinical impression about potential risk factors for the outcomes of revision surgery for failed total knee replacements. Using these results, a consensus group developed the final version of the index. The result of the nominal group process was the Knee Society Index of Severity, which was based on eight distinct domains. Each domain was divided into attributes and weights based on the questionnaire responses and consensus meeting. Actual case scenarios from five institutions were used to test interrater reliability and validity. The interrater reliability of the average score of all ratings was 0.95; the correlation of the criterion rating with the mean rating was 0.77. When three outliers were not included, the Pearson product correlation increased to 0.92. These data support the application of the Knee Society Index of Severity as a critical component of risk factor studies, effectiveness research, and cost-effectiveness analysis involving revisions of total knee replacements.

Evaluation of school-based HIV prevention education programs in New Jersey

This paper presents results from a process evaluation conducted by the New Jersey Department of Education (NJDOE). Representative samples of middle and high school superintendents, principals, lead health teachers, and HIV teachers provided information assessing whether local district policy content was consistent with the state's policy code, the dynamics of local policy development, and school district staff perceptions and practices regarding HIV education policies. NJDOE also was interested in determining: if inservice training was accessible to teachers assigned to provide HIV education; the scope and impact of HIV inservice programs; and the training needs of staff assigned to teach the HIV curriculum. Finally, NJDOE was interested in determining: local curricula scope, sequence, and approach; the extent to which local curricula were skills-based; and local expectations for instructional outcomes. As a result of the evaluation, program staff identified areas needing remediation and planned for program improvement in new areas.

Total knee arthroplasty after open reduction and internal fixation of fractures of the tibial plateau: a minimum five-year follow-up study

BACKGROUND

There is little information in the literature regarding the outcome of total knee arthroplasty following open reduction and internal fixation of fractures of the tibial plateau. The goal of this study was to evaluate the results of such procedures after a minimum of five years of follow-up.

METHODS

We retrospectively analyzed the outcomes of fifteen total knee arthroplasties performed at an average of 38.6 months (range, eight months to eleven years) after open reduction and internal fixation of a fracture of the tibial plateau in fifteen consecutive patients. The average duration of follow-up after the total knee arthroplasty procedures was 6.2 years (range, 5.4 to 11.1 years). The average age of the patients was fifty-six years (range, thirty-seven to sixty-eight years) at the time of the arthroplasty. We evaluated the outcomes on the basis of the Hospital for Special Surgery knee score, the Short Form-36 score, and radiographs of the knees.

RESULTS

The average Hospital for Special Surgery knee score was 51 points (range, 20 to 74 points) before the arthroplasty, and it increased to 80 points (range, 44 to 91 points) postoperatively. Four knees were scored as excellent, eight had a good result, one was rated as fair, and two had a poor result. The average Short Form-36 scores were 58.0 points for general health, 72.4 points for bodily pain, 72.1 points for mental health, 58.3 points for physical functioning, 84.6 points for physical role functioning, 81.0 points for social functioning, and 57.7 points for vitality. The average active postoperative arc of motion was 105 degrees (range, 70 degrees to 135 degrees ) compared with 87 degrees (range, 20 degrees to 125 degrees ) preoperatively. Incomplete radiolucencies were noted on all of the postoperative radiographs made after the total knee arthroplasties. There was a high rate of infection (three patients), patellar tendon disruption (two patients), and postoperative secondary procedures (three patients required closed manipulation). The patients with infection were considered to have a failure of treatment: two required arthrodesis, and one required a two-stage exchange.

CONCLUSION

On the basis of our results, we concluded that total knee arthroplasty after open reduction and internal fixation of a fracture of the tibial plateau decreases pain and improves knee function, but the procedure is technically demanding and is associated with a high failure rate (five of fifteen).

Behavioral and pharmacological treatment methods for pregnant smokers: issues for clinical practice

Active and passive exposure to tobacco smoke are the most serious and preventable causes of poor maternal, fetal, and infant outcomes in the United States. Unfortunately, the majority of pregnant smokers do not quit smoking before or during pregnancy or after childbirth. We describe a standardized behavioral counseling model and discuss issues to consider in recommending the use of pharmacotherapy during pregnancy. Although the Food and Drug Administration no longer classifies nicotine replacement therapy (NRT) as contraindicated during pregnancy, precautions should be carefully considered for use in this population. This paper provides a synopsis of the risks of exposure to tobacco smoke during pregnancy and the postpartum; estimates the population at risk and the potential for increased cessation if effective health education methods during pregnancy were routinely provided; presents a meta-analysis of "best practice" patient education methods for pregnant smokers; and estimates the number of pregnant heavy smokers who might be eligible for NRT. We suggest five issues for the physician to consider before recommending NRT medications to pregnant patients who are heavy smokers. The judicious use of NRT medications may significantly reduce harm to the infants of heavy smokers. More evidence derived from large population-based research, however, is needed to provide guidance to the physician about NRT eligibility, dose, scheduling, and effectiveness in clinical practice.

Rotating hinge total knee arthroplasty in severly affected knees

A consecutive series of 24 knees in 21 patients who received a Finn rotating hinge for primary (nine knees) or revision (15 knees) total knee arthroplasty between August 1993 and January 1997 was reviewed. The average followup was 33 months (range, 21-62 months) for all patients in the study. Seventeen patients (20 knees) were followed up for more than 2 years. Twenty-four knees (21 patients) were categorized according to Knee Society scoring criteria: 37.5% (nine knees) were Category A, 25% (six knees) were Category B, and 37.5% (nine knees) were Category C. Using the Knee Society knee and function scores, clinical and radiographic results were assessed and outcome analysis was determined. The average Knee Society knee score improved from 44 points (range, 5-64 points) before surgery to 83 points (range, 45-95 points) after surgery; the average functional score according to the Knee Society system improved from 10 points (range, 0-35 points) before surgery to 45 points (range, 0-100 points) after surgery. Pain and function markedly improved after surgery. For treatment of the most severely affected knees with compromised bone and ligamentous instability, the Finn total knee replacement appears to be an acceptable option. As a rotating hinge design, the prosthesis at early followup provides excellent pain relief, restoration of walking capacity, and stabilization, without evidence of early mechanical failure.

Evaluation of a smoking cessation intervention for pregnant women in an urban prenatal clinic

A smoking cessation and relapse prevention intervention was tested in an urban, prenatal clinic serving predominantly low-income, African-American women. At their first prenatal visit, 391 smokers were randomly assigned to an experimental (E) group to receive usual clinic information plus a prenatal and postpartum intervention or to a control (C) group to receive only usual clinic information. The intervention consisted of individual skills instruction and counseling by a peer health counselor on the use of a self-help cessation guide and routine clinic reinforcement. Among the E group (n = 193), 6.2% were cotinine-confirmed quitters at third trimester and among the C group (n = 198) the quit rate was 5.6%. Quitters were light smokers at entry into prenatal care. Many had tried to quit smoking at least once prior to pregnancy.

Factors affecting deep vein thrombosis rate following total knee arthroplasty under epidural anesthesia

A retrospective review was performed of 448 consecutive patients undergoing primary, unilateral, bicondylar, and cemented total knee arthroplasty under epidural anesthesia by three surgeons to determine factors contributing to deep vein thrombosis rate. All had venography on the fourth or fifth postoperative day and received aspirin and elastic stockings as their only thromboprophylaxis. The overall deep vein thrombosis rate was 41% (2% had proximal clots). The rate of deep vein thrombosis was not related to obesity, history of heart disease, hypertension, prior malignancy, smoking, diagnosis of osteoarthritis, duration of surgery, type of local anesthetic used, or the use of postoperative epidural analgesia. The rate of deep vein thrombosis varied significantly between surgeons: one surgeon had an overall deep vein thrombosis rate of 58% (proximal thrombi, 4%) whereas the other two surgeons had a deep vein thrombosis rate of 35% (proximal clot thrombi, 1%). A number of possible mechanisms to explain the variation in deep vein thrombosis rates between surgeons are provided.

Prevalence of anabolic steroid use by male and female adolescents

This study was performed to determine the prevalence of anabolic steroid use among male and female high school students. A total of 1,010 questionnaires were distributed in five high schools in a relatively affluent school district (Group I, 510 surveys with a 92.4% response rate) and five high schools in a relatively less affluent school district (Group II, 500 surveys with an 86.0% response rate). Three percent of all high school students reported using anabolic steroids: 5.0% of males and 1.4% of females. Among Group I students, 5.9% of all athletes reported using anabolic steroids, whereas only 1.5% of all Group II athletes admitted using them. A 10.2% usage of anabolic steroids among Group I male athletes was observed, but only 2.8% of Group II male athletes reported their use. The median age for anabolic steroid consumption was 17 yr. The primary source of anabolic steroids was the black market (85.2%), while physicians directly supplied anabolic steroids to only 7.4% of the adolescents. It appears that within the high school adolescent population, Group I male athletes are the primary consumers of these drugs, with a reported 10.2% prevalence.

Pharmacologic and behavioral effects of EMD 28422: a novel purine which enhances (3H) diazepam binding to brain benzodiazepine receptors

A novel purine, (N6-2-(4-chlorophenyl)-bicyclo 2.2.2.-octyl-(3)-adenosine) EMD 28422 increases the binding of (3H) diazepam to benzodiazepine receptors in vivo within 10 min after intraperitoneal administration. This increase in (3H) diazepam binding is due to an increase in the number of benzodiazepine receptors (Bmax) rather than an altered affinity of the radioligand for receptor (Kd), EMD 28422 protects mice against pentylenetetrazole and caffeine-induced seizures and potentiates the anticonvulsant action of subeffective doses of diazepam in a dose-dependent fashion. Furthermore, EMD 28422 also produces a significant increase in punished responding in a conflict situation (rats), and a long-lasting, dose-dependent decrease in spontaneous motor activity (mice). In contrast, neither EMD 39011 nor adenosine (the two component molecules of EMD 28422) possess anticonvulsant properties at doses up to five mole-equivalents of EMD 28422. These data indicate that the purine EMD 28422 produces a spectrum of pharmacologic effects similar to the benzodiazepines, yet in contrast to the benzodiazepines (and other purines), increases benzodiazepine receptor number. Thus, EMD 28422 may represent the prototype of a class of synthetic purines exerting a unique neurochemical effect on benzodiazepine receptors and possessing several therapeutic actions of the benzodiazepines.

Guidelines for health education in maternal and child health

Guidelines are presented for specifying objectives, identifying resources, selecting methods and evaluating the health education component for maternal and child health programmes. Examples of the application of the principles are integrated with the Guidelines. Diagnostic, planning, organizational, administrative and evaluative procedures are presented around a model of health education which emphasizes: a) the careful delineation of the health problem; b) the specification of behaviours influencing the health problem; c) setting priorities among target behaviours on the basis of their relative epidemiological importance and their changeability; and d) the identification of factors that predispose, enable and reinforce the behaviour.

Western encephalomyelitis virus infection in "indicator" chickens in southern Alberta

Sera from indicator chicken flocks situated in southern Alberta near Lethbridge were tested by the hemagglutination-inhibition (HI) technique for antibodies to Western, Eastern and St. Louis Encephalitis viruses during the summer and early fall of the four years 1964 to 1967.One chicken in 1964, 90 in 1965 and five each in 1966 and 1967 were positive to Western encephalomyelitis (WE) virus by hemagglutination-inhibition tests. All of the positive sera were confirmed by neutralization test (NT) in infant mice. No antibodies to the Eastern and St. Louis viruses were detected. Infection with WE virus was detected in each of the four years, indicating that WE virus is endemic to southern Alberta with a marked seasonal incidence occurring between the second week in August and the third week in September. An improved technique for filtering sera is described.

Epizootic of western encephalomyelitis virus infection in equines in Alberta in 1965

The epizootic of equine encephalomyelitis in 1965 in Alberta was proved to be due to Western Encephalomyelitis virus infection by serological findings and virus isolations.Sixty-three horses of 88 tested, showed a diagnostic rise of CF antibodies to Western Encephalomyelitis virus. Western Encephalomyelitis virus was isolated from 5 brains of horses. Homologous antibodies were shown in 3 of these animals, the only ones from which blood specimens were received. For the first time virological evidence is given that Western Encephalomyelitis virus infection in horses is found in more areas of Alberta and in regions situated further North than those previously suspected.