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Biomedical subjects

J Engler

Publications and source records attributed to J Engler.

At least 19 recordsLinked to original sources
PubMed2003

First tests of a liquid ionization chamber to monitor intensity modulated radiation beams.

First measurements with a prototype ionization chamber are described to be applied in online monitoring of modulated fields in radiation therapy. The liquids isooctane, isononane (TMP) and tetramethylsilane (TMS) are used in a high purity grade in order to realize high current signals for electronic read-out in parallel at frequencies exceeding 10 Hz. Signals of more than a factor 4 with respect to isooctane, analysis grade, are obtained. With an electrode structure of 400 pads, a uniformity in efficiency within 1.2% has been measured. The penumbra of a multileaf collimator could be resolved. Theoretical examination verifies that the free electrons in the liquids cause higher signals when the measured currents are compared with expectation for ion transport only.

Computer Simulation↗
PubMed2002

A randomised crossover trial of post-operative cognitive and psychomotor recovery from benzodiazepine sedation: effects of reversal with flumazenil over a prolonged recovery period.

OBJECTIVE: To study the post-operative cognitive and psychomotor recovery from midazolam conscious sedation, after reversal with the benzodiazepine antagonist flumazenil over a prolonged recovery period. DESIGN: A prospective, double-blind, randomised, crossover trial. SETTING: Out-patient Sedation Department, Newcastle Dental Hospital and School METHOD: Eighteen patients, ASA I or II, received midazolam on two separate occasions to undergo equivalent dental treatment. Following treatment patients were reversed with intravenous flumazenil or saline (placebo) at alternate appointments. Assessment of mood and cognitive function was undertaken using a highly sensitive and specific computerised battery of cognitive tests administered by telephone. Cognitive and psychomotor tests were administered prior to sedation and every hour for 6 hours post reversal. RESULTS: Results indicated no significant effect of flumazenil on simple reaction time and choice reaction time but did show a trend of reversing the effects of midazolam on numeric working memory and word recognition. CONCLUSION: The cognitive and psychomotor effects of the sedation were not fully reversed by flumazenil. Cognitive impairments were still present up to 6 hours post-reversal, despite patients appearing clinically more alert. This has important implications for treatment protocols and discharge instructions.

Adolescent↗
PubMed2001

Maintenance of a smoking cessation program in public health clinics beyond the experimental evaluation period.

OBJECTIVES: As phase 3 of a study to evaluate a smoking cessation program in public health practice, the authors assess the maintenance and impact of the It's Time smoking cessation program in seven public maternal and child health clinics in Chicago. METHODS: The authors interviewed 404 clinic patients in the study's baseline phase (prior to introduction of the It's Time intervention program), and 610 in the program maintenance phase (in the year after experimental evaluation had ended) to assess exposure to smoking cessation interventions offered at the clinic, and smoking cessation outcomes (quit, actions toward quitting, scores on action, motivation, readiness, and confidence scales). The authors controlled for clustering of smokers within clinics, smokers' characteristics prior to clinic visit, and type of clinic service. They compared outcomes by study group (control or intervention) to which each clinic had been assigned in the earlier experimental phase. RESULTS: Compared to baseline, smokers in the maintenance phase had greater exposure to posters, provider advice and booklet, and better outcomes on seven of eight smoking cessation measures, including quitting. These improvements were larger for clinics with prior experience implementing It's Time. CONCLUSION: Participation in the experimental evaluation of the It's Time program prepared and possibly motivated the clinics to continue the program. Continuing the program resulted in greater delivery of interventions and improved smoking cessation outcomes for smokers in the clinics.

Adult↗
PubMed2001

Acute synovitis, fever and rash possibly caused by metallic debris from a loosened knee prosthesis in a patient with rheumatoid arthritis.

A 39-year-old woman with long-standing seropositive rheumatoid arthritis who had a total replacement of her left knee with a modular prosthesis in 1994 presented with fever, pruritic rash, and acute synovitis of that joint following local trauma. Synovial fluid showed a charcoal-like color, and contained abundant phagocytes laden with metal particles. In patients with rheumatoid arthritis who have undergone total joint replacement, metal particle reactions and possible hyper-sensitivity should be added to the list of potential causes of superimposed acute synovitis and systemic manifestations.

Journal Article↗
PubMed2000

Minimal smoking cessation interventions in prenatal, family planning, and well-child public health clinics.

OBJECTIVES: This study assessed the prevalence and effectiveness of smoking cessation interventions for women of childbearing age in public health clinics. METHODS: Smokers in prenatal, family planning, and well-child services in 10 public health clinics (n = 1021) were interviewed 5 to 8 weeks after a medical visit to assess their exposure to smoking cessation interventions and smoking cessation outcomes. RESULTS: Depending on clinic service and intervention component (poster, video segment, provider advice, booklet), 16% to 63% of women reported exposure to an intervention component during their visit. Women in prenatal services received more interventions and had better outcomes than those in the other services. CONCLUSIONS: Exposure to more interventions increased readiness and motivation to quit and the number of actions taken toward quitting.

Adolescent↗
PubMed2000

The effect of a structured smoking cessation program, independent of exposure to existing interventions.

OBJECTIVES: This study assessed the effectiveness of a smoking cessation program for women in public health clinics, controlling for reported exposures to 4 common intervention components (provider advice, booklet, video segment, posters) among smokers in the control group. METHODS: After a baseline control period, 10 pair-matched clinics were randomly assigned to study groups. A total of 1042 smokers in the combined baseline and control groups and 454 smokers in the intervention group completed a preintervention questionnaire and a postintervention telephone interview 5 to 8 weeks later. Eight smoking outcomes, including quitting, were analyzed for the effect of reported exposure to intervention components, experimental program, and clinic service. RESULTS: Greater exposure to intervention components, being in the experimental program, and being seen in prenatal clinics independently improved smoking outcomes. CONCLUSIONS: The number of interventions reported by smokers in the control group ranged from none to 4 and varied across clinic services. The experimental program we tested produced better outcomes than the minimal smoking cessation interventions already existing in the control clinics, after we controlled for whether smokers were or were not exposed to these interventions.

Ambulatory Care Facilities↗
PubMed1999

Evaluation of a motivational smoking cessation intervention for women in public health clinics.

BACKGROUND: A multicomponent motivational smoking cessation intervention was evaluated in 33 prenatal, family planning, and pediatric services in 12 public health clinics. Clinic-based intervention components were implemented by clinic personnel as part of routine medical visits. METHODS: The evaluation design included pre- and postintervention measurements of multiple study outcomes in a baseline (all clinics prior to the start of the intervention) and an experimental period (matchedpair random assignment of clinics to intervention or control conditions). Subjects were 683 (baseline) and 1,064 (experimental) smokers with measurements of smoking outcomes at both times. Mixed-effects regressions analyzed individual outcomes clustered within clinics and services. RESULTS: Control and intervention clinics had similar outcomes in the baseline period. In the experiment, outcomes improved in the intervention but not in the control clinics. Compared to controls, smokers exposed to the intervention were more likely to have quit (14.5 versus 7.7%) or take actions toward quitting and had higher mean action, stage of readiness, and motivation to quit scores. These positive effects persisted when clustering within clinics and services was controlled. CONCLUSIONS: This intervention, implemented by clinic personnel as part of routine medical visits, was effective under these natural conditions across different types of clinic service.

Adult↗
PubMed1999

T cell reactivity to DR*0401- and DQ*0302-binding peptides of the putative autoantigen IA-2 in type 1 diabetes.

Type 1 diabetes is thought to be an autoimmune disease mediated by T lymphocytes recognizing critical islet cell antigens. Recently, the tyrosine phosphatase like protein IA-2 was suggested as a putative autoantigen in type 1 diabetes since autoantibodies are detected in sera of diabetic patients and prediabetic subjects. Similarly, T cell responses of peripheral blood lymphocytes of type 1 diabetic patients to this protein have been described. Only very few data is available about immunodominant epitopes of IA-2 recognized by T cells. We have studied T cell responses in type 1 diabetic patients and age and partly HLA matched controls to IA-2 peptides designed to bind HLA risk alleles of IDDM as DR*0401 and DQ*0302. Both diabetic patients and controls responded to IA-2ic and some of the peptides. Three peptides of the C-terminal region of IA-2 were recognised by T cells of a fraction of diabetic patients but at least two of these peptides triggered also T cell responses in DR*0401/DQ*0302-matched controls. Most peptides bound to different HLA alleles ("promiscous binders"). The identification of autoantigenic epitopes may offer clues to related sequences e.g. of viral origin what relates to models of diabetes pathogenesis ("molecular mimicry"). Secondly, the design of antigen- or even epitope-specific immune intervention strategies aiming at tolerization of disease specific T cells in type 1 diabetes may profit from the knowledge of immunodominant T cell epitopes of a putative autoantigen.

Adolescent↗
PubMed1997

[Calculation of lavage volume in transurethral prostate resection (TURP)].

PURPOSE: Evaluation of the relationship between ethanol concentration in expired air and the amount of absorbed irrigation fluid in patients who undergo a transurethral resection of the prostate. METHODS: 76 patients were evaluated in a prospective study. The irrigation fluid contained 1.92 w/w% of ethanol. The ethanol concentration in breath was measured at least every 10 minutes with a Alcotest 7410 (Dräger) or a Biomed 3010 (Biotest). Documented values: breath ethanol concentration, mean arterial pressure, heart rate, haemoglobin concentration, serum sodium concentration, the amount of irrigation fluid, the time of operation, special events, therapeutic interventions. A modification of the Widmark formula was used for calculating the amount of absorbed irrigation fluid from the breath ethanol concentration. RESULTS: A rise of the ethanol level above 0.2/1000 was observed in 10 patients. No clinically significant difference in heart rate and blood pressure during surgery between the 24 patients with no alcohol in breath and the 10 patients with more than 0.2/1000 was observed. Prolonged duration of resection and greater amount of used irrigation fluid correlated with higher ethanol concentration in breath. During the study period no patient developed the clinical features of a transurethral resection syndrome. CONCLUSIONS: If 2 w/w% of ethanol is added to the irrigation fluid, breath ethanol concentration under 0.2/1000 may be considered harmless, while values above 0.2/1000 are predictors of massive absorption of irrigation fluid. In our patients, the addition of ethanol to the irrigation fluid has been a suitable and easy way to monitor the absorption of irrigation fluid, if the ethanol concentration in the breath is measured every ten minutes. If 2 w/w% of ethanol have been added to the irrigation fluid, the absorbed volume (E) can be estimated using the formula: E = 37.5 x body weight (kg) x ethanol concentration (/1000).

Aged↗
PubMed1994

[Therapy and results of fresh lateral instability of the upper ankle joint].

During a retrospective study we especially examined the late outcome in therapy of injuries of the lateral capsula ligament-lesions in 210 patients. In addition we scrutinized the literature on this subject within the last 60 years, concerning the results of different therapy methods were checked. 203 collective writings on this subject, 23,279 patients and our own results achieved in the BG Accident Hospital in Murnau (Germany) all added up to 23,389 patients. We did not only observe the subjective opinion regarding the outcome of the therapy but also the socio-economic factors, such as the duration of incapability to work and do sports. Emphasis was laid on the remaining complaints: reduction of movement, swelling, pain during stress and instability (in the sense of recurring injuries). The results of this thesis show the dependence of the therapy in respect to the age of the patient. So we have developed a different therapy-concept for those under age of 30 and for those over the age of 30 years.

Adult↗
PubMed1988

[Laser Doppler flowmetry in vital bone transplantation. Experimental and clinical results].

Laser Doppler Flowmetry allows the measurement of the blood flow rate of different types of tissue. Rib on a muscle pedicle was compared with rib on a vascular pedicle in an animal experiment. The morphological results were compared with the LDF-results. During eleven clinical transfers of iliac crest bone grafts and one osteocutaneous scapular flap the blood flow values were measured intraoperatively before and after the transplantation. Postoperative monitoring was possible for 48 hours with the endoscopic probe and a screw implant. The blood flow of vascularized bone transplants is excellent and even rises post-operatively in some cases.

Animals↗