Determining the value of the abdominal core health quality collaborative to support regulatory decisions

PURPOSE

The study objective is to document value created by real-world evidence from the Abdominal Core Health Quality Collaborative (ACHQC) for regulatory decisions. The ACHQC is a national effort that generates data on hernia repair techniques and devices.

METHODS

Two retrospective cohort evaluations compared cost and time of ACHQC analyses to traditional postmarket studies. The first analysis was based on 25 reports submitted to the European Medicines Agency of 20 mesh products for post-market surveillance. A second analysis supported label expansion submitted to the Food and Drug Administration, Center for Devices and Radiological Health for a robotic-assisted surgery device to include ventral hernia repair. Estimated costs of counterfactual studies, defined as studies that might have been done if the registry had not been available, were derived from a model described in the literature. Return on investment, percentage of cost savings, and time savings were calculated.

RESULTS

45,010 patients contributed to the two analyses. The cost and time differences between individual 25 ACHQC analyses (41,112 patients) and traditional studies ranged from $1.3 to $2.2 million and from 3 to 4.8 years, both favoring use of the ACHQC. In the second label expansion analysis (3,898 patients), the estimated return on investment ranged from 11 to 461% with time savings of 5.1 years favoring use of the ACHQC.

CONCLUSIONS

Compared to traditional postmarket studies, use of ACHQC data can result in cost and time savings when used for appropriate regulatory decisions in light of key assumptions.

A77 THE ASSOCIATIONS OF OBJECTIVELY ASSESSED SEDENTARY TIME AND STEP COUNT ON ULCERATIVE COLITIS OUTCOMES

Background

Physical activity has been associated with positive health outcomes in those with Ulcerative Colitis (UC). The extent to which other more prominent behaviours occurring throughout the 24-hour day (i.e., sitting, standing, lying down, and stepping) are associated with UC outcomes is unknown.

Purpose

The purpose of this study was to explore whether objectively measured time spent sitting, lying down, standing, and stepping were associated with Total Mayo score (TMS), fecal calprotectin (FCP), and C-reactive protein (CRP) in patients with UC.

Method

Patients were recruited from the Foothills Medical Center in Calgary, Alberta and were given activPAL^TM accelerometers (PAL Technologies Limited, Glasgow, UK) to wear on their thigh for 7 days. Step count, sitting time, standing time, and time lying down (excluding sleep) were recorded for a minimum of 4 days, including at least one day on the weekend. TMS was used to determine disease activity and patients were categorized into normal/mild (TMS score <6) or moderate/severe (TMS score 6). FCP, a marker of gut inflammation, was measured using stool samples. Blood samples were collected to measure serum CRP, a marker of systemic inflammation. Univariate analysis of covariance (ANCOVA) was used to evaluate associations between the activPAL^TM daily activity variables, TMS, FCP (< or >250ug/g) and CRP (< or > 5 mg/L). Analyses were controlled for age, sex, body mass index (BMI), and antibiotic use.

Result(s)

Patients (N=29; 15 male, 14 female) were on average 38 years of age (SD=12.1). The average BMI was 26.2 kg/m² (SD=3.2). Based on TMS, 14 had moderate/severe disease activity and 16 had normal/mild disease activity. Average CRP was 2.16 mg/L (SD=2.49) while the mean FCP was 954.5 ug/g (SD=1427.7). Patients recorded an average of 8,137 steps (SD=3,051) per day. Average standing time was 240 minutes (SD=84) per day, sitting time was 503 minutes (SD=131) per day, and time spent lying down was 527 minutes (SD=111) per day. FCP was negatively associated with step count (D=-2,134 steps, 95% CI: -4,360 to 93, p=0.06). Patients with lower FCP values (<250mg/g) spent 60 fewer minutes sitting (p=.25), and 52 more minutes standing (p=.12) during the day compared to patients with higher FCP values (>250mg/g). Patients with normal/mild disease severity (TMS <6) spent 83 fewer minutes per day sitting compared to those with moderate/severe disease severity (TMS >6, p=.12). CRP was not associated with any behavioural outcomes.

Conclusion(s)

In our study, daily steps appeared to be most strongly associated with FCP. While not statistically significant, patients with lower FCP reported less sitting and more standing compared to those with higher FCP. Future studies with larger sample sizes should continue to explore these activity behaviours and their potential associations with UC disease outcomes.

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Alberta's Collaboration of Excellence for Nutrition in Digestive Diseases (ASCEND)

Disclosure of Interest

B. Chiew: None Declared, K. Lyden Consultant of: PAL Technologies, the company that manufactures the activPAL device., A. Schick: None Declared, C. Ohland: None Declared, K. McCoy: None Declared, S. Kaur: None Declared, M. Yousuf: None Declared, L. Taylor: None Declared, M. Raman Shareholder of: LyfeMD – Director, Shareholder, Grant / Research support from: Pfizer, Takeda, Speakers bureau of: Fresenius Kabi, Pfizer, Mckesson, Takeda, Lupin, J. Vallance Grant / Research support from: Canada Research Chairs Program

The PerPAIN trial: a pilot randomized controlled trial of personalized treatment allocation for chronic musculoskeletal pain-a protocol

BACKGROUND

The therapy of chronic musculoskeletal pain (CMSP) is complex and the treatment results are often insufficient despite numerous therapeutic options. While individual patients respond very well to specific interventions, other patients show no improvement. Personalized treatment assignment offers a promising approach to improve response rates; however, there are no validated cross-disease allocation algorithms available for the treatment of chronic pain in validated personalized pain interventions. This trial aims to test the feasibility and safety of a personalized pain psychotherapy allocation with three different treatment modules and estimate initial signals of efficacy and utility of such an approach compared to non-personalized allocation.

METHODS

This is a randomized, controlled assessor-blinded pilot trial with a multifactorial parallel arm design. CMSP patients (n = 105) will be randomly assigned 1:1 to personalized or non-personalized treatment based on a cluster assignment of the West Haven-Yale Multidimensional Pain Inventory (MPI). In the personalized assignment condition, patients with high levels of distress receive an emotional distress-tailored intervention, patients with pain-related interference receive an exposure/extinction-tailored treatment intervention and patients who adapt relatively well to the pain receive a low-level smartphone-based activity diary intervention. In the control arm, patients receive one of the two non-matching interventions. Effect sizes will be calculated for change in core pain outcome domains (pain intensity, physical and emotional functioning, stress experience, participant ratings of improvement and satisfaction) after intervention and at follow-up. Feasibility and safety outcomes will assess rates of recruitment, retention, adherence and adverse events. Additional data on neurobiological and psychological characteristics of the patients are collected to improve treatment allocation in future studies.

CONCLUSION

Although the call for personalized treatment approaches is widely discussed, randomized controlled trials are lacking. As the personalization of treatment approaches is challenging, both allocation and intervention need to be dynamically coordinated. This study will test the feasibility and safety of a novel study design in order to provide a methodological framework for future multicentre RCTs for personalized pain psychotherapy.

TRIAL REGISTRATION

German Clinical Trials Register, DRKS00022792 ( https://www.drks.de ). Prospectively registered on 04/06/2021.

Adapting a Participatory and Ecosystem-Based Assessment Impacted by the Pandemic: Lessons Learned With Farmers in Tajikistan

The paper presents a systemic and participatory assessment approach and scrutinizes how methodological changes necessitated during the Covid-19 pandemic implicated the process and its outcomes. The approach was applied in rural Tajikistan to evaluate changes effected by a development project that promoted the enhancement of biodiversity and ecosystem services in agrarian landscapes. The central building block of the assessment consisted of participatory workshops in 2018 and 2020 with farmers and other stakeholders to develop a systemic knowledge map and to evaluate the promoted strategies based on local expertise. The methodological basis was MARISCO (adaptive MAnagement of vulnerability and RISk at COnservation sites), a holistic and participatory approach to ecosystem-based assessment and management that requires well-trained facilitators. While the activities in 2018 could be implemented as planned, major changes in the work plan were necessary in 2020 due to severe travel restrictions and social distancing rules. Conducting virtual workshops was not possible, as it would have excluded key stakeholders from the process. Instead of conducting a comprehensive assessment workshop guided by two German MARISCO facilitators as originally planned, a series of short and small workshops could be realized. These workshops were facilitated by Tajik scientists after receiving virtual training from their German colleagues. Although it was possible to bring the assessment to a satisfactory conclusion, the methodological changes revealed significant drawbacks. Radical simplifications of the methods were necessary that led to reduced depth of the assessment and missed learning opportunities for participants. Limited experience in workshop guidance by the new facilitators posed challenges to the participatory process and the quality of its outcomes. While the adapted method created training effects that would otherwise have been missed, it also put additional pressure on the capacities of local partners. Our experience during the pandemic offers valuable lessons learned for future applications of systemic-participatory approaches. Whereas, a complete shift to remote applications is problematic, there is a need to put greater emphasis on capacitating local partners. Methodological trade-offs are necessary for partially remote working processes, but principles of participation and systemic thinking should not be compromised.

Living lab AI4U - artificial intelligence for personalized digital mental health promotion and prevention in youth

Background

Youth are particularly affected by mental health problems, but their use of preventive interventions remains limited. The advances in Artificial Intelligence (AI) enable the development of digital interventions for mental health promotion and prevention. This applies to ecological momentary interventions (EMI), which offer adaptive training components in daily life.

Methods

In a preparatory phase, focus groups (N = 2, aged: 15-21 years) and a representative survey (N = 666, aged: 16-24) with young individuals as well as qualitative interviews with stakeholders in routine public mental health provision were conducted.

Results

None of the stakeholders used digital interventions in their everyday work but were interested in their use. The importance of data protection and security, usability, and participation of the target population in all stages of the research process was emphasized. The risk of a digital divide, acceptance of used terminology, and difficulties of structural embedding were mentioned as important barriers for successful implementation. Young individuals had a positive attitude toward digitization and AI and their use in mental health promotion and prevention and underlined the importance of practical benefits for users. They had a pragmatic attitude toward data use policies. Around 70% of young individuals were already using mHealth apps. Psychological distress was associated with the use of, and positive attitude towards, mHealth apps.

Discussion

Findings have contributed to the ongoing main phase. The living lab AI4U will be carried out in transdisciplinary projects involving direct participation of relevant stakeholders, users from the target population and an interdisciplinary research group. Each of these projects includes one or more real-world experiments. These will be embedded in a transdisciplinary infrastructure, which will ensure ongoing quality assurance, sustainability assessment, public relations and networking.

Longitudinal determination of resilience in humans to identify mechanisms of resilience to modern-life stressors: the longitudinal resilience assessment (LORA) study

Resilience is the maintenance and/or quick recovery of mental health during and after periods of adversity. It is conceptualized to result from a dynamic process of successful adaptation to stressors. Up to now, a large number of resilience factors have been proposed, but the mechanisms underlying resilience are not yet understood. To shed light on the complex and time-varying processes of resilience that lead to a positive long-term outcome in the face of adversity, the Longitudinal Resilience Assessment (LORA) study has been established. In this study, 1191 healthy participants are followed up at 3- and 18-month intervals over a course of 4.5 years at two study centers in Germany. Baseline and 18-month visits entail multimodal phenotyping, including the assessment of mental health status, sociodemographic and lifestyle variables, resilience factors, life history, neuropsychological assessments (of proposed resilience mechanisms), and biomaterials (blood for genetic and epigenetic, stool for microbiome, and hair for cortisol analysis). At 3-monthly online assessments, subjects are monitored for subsequent exposure to stressors as well as mental health measures, which allows for a quantitative assessment of stressor-dependent changes in mental health as the main outcome. Descriptive analyses of mental health, number of stressors including major life events, daily hassles, perceived stress, and the ability to recover from stress are here presented for the baseline sample. The LORA study is unique in its design and will pave the way for a better understanding of resilience mechanisms in humans and for further development of interventions to successfully prevent stress-related disorder.

[Resilience trajectories-examples from longitudinal studies]

BACKGROUND

According to current research concepts resilience can be defined as adaptation to past and ongoing exposure. Accordingly, adaptation to exposure is a dynamic process, which can be different in different population groups. Prospective longitudinal studies provide unique opportunities to investigate resilience processes.

OBJECTIVES

The aim of this article is to define the concept of resilience, describe examples of longitudinal studies investigating resilience in children, adults and older individuals, exemplary describe four ongoing longitudinal resilience studies in which the authors of the article are participating and identify and analyze methodological challenges in empirical resilience research.

MATERIAL AND METHODS

This study was based on a qualitative literature review of published prospective studies investigating resilience listed in PubMed and study protocols of the four longitudinal studies.

RESULTS

The exemplarily described studies have shown that resilience processes are changeable in all age groups and subject to a variety of influencing factors. The specific and potentially age-associated types of alterations have so far been difficult to determine and need further clarification.

DISCUSSION

In view of the dynamic course of resilience, prospective longitudinal studies are urgently needed. Prospective longitudinal studies have the potential to identify resilience mechanisms and predictors of the course of resilience in different population groups, such as children, adolescents, adults and older individuals. Furthermore, resilience research needs to develop an improved and precise assessment of exposure to stressors.

People-Centered and Ecosystem-Based Knowledge Co-Production to Promote Proactive Biodiversity Conservation and Sustainable Development in Namibia

Growing levels of uncertainty and vulnerability generated by land use conversion and climate change set demands on local communities and national institutions to build synergies between the diverse array of knowledge systems in order to provide policy makers and practitioners with the best available information to decide what urgent actions must be taken. Science policy arenas and agreements such as the Intergovernmental Platform on Biodiversity and Ecosystem Services (IPBES) and the Convention on Biological Diversity (CBD) recognize the importance of different types of knowledge and the need for broad stakeholder involvement, yet the use of indigenous and local knowledge (ILK) in environmental decision-making processes is still underdeveloped. This study involved working with local stakeholders, using the MARISCO method (adaptive MAnagement of vulnerability and RISks at COnservation sites) to carry out a systematic situation analysis of the existing socioenvironmental conditions. The assessments were conducted in the Kavango East Region in northern Namibia with the participation of inhabitants of the Khaudum North Complex, a protected area network covering wooded savannahs belonging to the Northern Kalahari sandveld. General outcomes of the assessments and evaluations made by the local stakeholders concerning the most critical drivers of degradation of the ecosystems appeared to support existing scientific knowledge of the study area, demonstrating that community-based assessments can provide valuable information about socioecological systems where scientific data are scarce. The findings of this study also highlight the importance of power dynamics for the implementation of participatory processes and the interpretation of their outcomes.

Hair and saliva test fails to identify allergies in dogs

OBJECTIVES

Several companies offer saliva and/or hair tests for food and environmental allergies in companion animals, but provide no validation of test accuracy. We examined one such hair and saliva allergy test to determine whether it could reliably differentiate between a normal dog and an allergic dog, and to examine test repeatability.

MATERIALS AND METHODS

Ten fur and saliva samples were submitted from a known allergic dog and a normal, non-allergic dog. Five fake fur samples and water were also submitted to determine whether the test could differentiate between a real dog and toy animal. The company performed testing for 128 food and environmental allergens. Statistical analyses were performed to determine whether the response distribution differed significantly between dogs, using the Pearson chi-square coefficient, as well as to determine test-retest reliability by calculating Cohen's kappa for each allergen.

RESULTS

The distribution of test results from samples obtained from allergic, non-allergic or fake dogs was not different from that expected due to random chance. Test-retest reproducibility was poor to slight.

CLINICAL SIGNIFICANCE

Hair and saliva testing should not be used to diagnose allergies and is not a substitute for veterinary-directed allergy evaluation and diagnostics.

Apical filling characteristics of carrier-based techniques vs. single cone technique in curved root canals

OBJECTIVES

In this in vitro study, we assessed filling characteristics (adaptation, homogeneity, sealer percentage, position of the carrier) of warm and cold obturation methods in curved root canals.

MATERIALS AND METHODS

A reciprocating method was used to prepare 90 curved roots (25 ° average curvature) to an apical size of 25.08. They were then obturated with either (A) Guttafusion (VDW, Munich, Germany), (B) Thermafil (Maillefer, Ballaigues, Switzerland) or (C) single cone technique using 25.08 gutta-percha (VDW) and sealer (2Seal easymix) (n = 30 each group). Five sections in 1-mm steps were obtained from each root, beginning 1 mm short of the apex. The percentage of voids in contact with root canal walls (PVO), the proportion of voids per area (PVA) and the percentage of sealer per area (PSA) were measured.

RESULTS

Little to no differences between Guttafusion and Thermafil were seen in curved root canals with respect to adaptation and homogeneity in the apical region. Both methods showed significantly better adaptation and homogeneity than the single cone technique. The proportion of sealer was significantly greater when roots were obturated with Guttafusion than with Thermafil, but both warm obturation techniques had significantly smaller sealer areas than the single cone technique.

CONCLUSIONS

Compared to the single cone technique, a more favourable root canal filling with less sealer could be expected from both warm obturation techniques in curved root canals.

CLINICAL RELEVANCE

The easier-to-handle Guttafusion leads to comparable results as Thermafil in curved root canals.

Associations of fatty liver disease and other factors affecting serum SHBG concentrations: a population based study on 1657 subjects

Sex hormone binding globulin (SHBG) is a glycoprotein expressed predominantly in the hepatocytes. It regulates the transport of sex steroid hormones in the blood stream to their target tissues. The expression of the SHBG gene is subject to multifactorial regulation including hormonal, metabolic, and nutritional aspects. Against this background, we investigated the effect of fatty liver and metabolic syndrome, together with other parameters, on serum SHBG concentrations in a population-based cohort in Germany. This cross-sectional study included 870 women and 787 men (average age 42.3±12.8 years), who underwent ultrasound screening for fatty liver in addition to providing a complete medical history and undergoing physical and laboratory examination. Fatty liver was diagnosed on ultrasound criteria in 159 women (18.3%) and 287 men (36.5%). Fatty liver was shown to exert a significant influence on serum SHBG concentrations in men and in premenopausal women. Men with grade 1 fatty liver had a 1.96-fold increased risk (95%-confidence interval=1.28-3.02; p=0.0022) and postmenopausal women with grade 1 fatty liver a 2.4-fold risk (95%-confidence interval=1.11-5.27; p=0.0267) for low SHBG concentrations. Among metabolic parameters, HDL-C represented as affecting factor in men (p=0.0058) and premenopausal women (p=0.0002), while cholesterol only showed an association in premenopausal women (p=0.0439) and triglyceride in postmenopausal women (p=0.0436). No association of concentrations of SHBG and metabolic syndrome was observed. Age, BMI and waist-to-hip ratio also influence the SHBG concentration. Based on these findings, we conclude that fat accumulation in the liver influences SHBG concentrations in men and premenopausal women.

Application of the EBSD technique to describe the initiation and growth behaviour of microstructurally short fatigue cracks in a duplex steel

Up to 90% of the fatigue life of engineering alloys results from the initiation and propagation of microstructurally short cracks. Owing to their strong interactions with microstructural features, e.g. grain and phase boundaries, they exhibit substantially non-uniform propagation kinetics as compared with the growth rate of long cracks, which can be well described using a power-law function of the range of the stress-intensity factor DeltaK. In the present paper interactions between the crystallographic misorientation of grain and phase boundaries and microcracks in an austenitic/ferritic stainless steel are discussed and quantified by means of fatigue experiments in combination with the electron backscattered diffraction technique. In the second part a numerical model for the simulation of microcracks is introduced, which is capable of taking real microstructural arrangements into consideration.

Down-regulation of the desmosomal cadherin desmocollin 3 in human breast cancer

In previous studies using cDNA microarray analysis, we have identified an expressed sequence tag which is consistently down-regulated in six human breast tumor cell lines. In the current study, we have determined this tag to be part of the mRNA sequence of human desmocollin 3, a member of the cadherin superfamily of proteins and an integral component of desmosomes. Desmosomes are sites of adhesion between adjacent cells in layers of epithelia, as well as in some non-epithelial tissues, and play an important role in the maintenance of tissue structure. Northern analysis, quantitative real-time polymerase chain reaction assay and Western blot analysis showed that desmocollin 3 is present in normal and immortalized human mammary epithelial cells, but consistently exhibits a significant, and often complete, down-regulation in breast cancer cell lines and primary breast tumors, both at the mRNA and protein levels.

Mutual information analysis as a tool to assess the role of aneuploidy in the generation of cancer-associated differential gene expression patterns

Most human tumors are characterized by: (1) an aberrant set of chromosomes, a state termed aneuploidy; (2) an aberrant gene expression pattern; and (3) an aberrant phenotype of uncontrolled growth. One of the goals of cancer research is to establish causative relationships between these three important characteristics. In this paper we were searching for evidence that aneuploidy is a major cause of differential gene expression. We describe how mutual information analysis of cancer-associated gene expression patterns could be exploited to answer this question. In addition to providing general guidelines, we have applied the proposed analysis to a recently published breast cancer-associated gene expression matrix. The results derived from this particular data set provided preliminary evidence that mutual information analysis may become a useful tool to investigate the link between differential gene expression and aneuploidy.

Tissue plasminogen activator and plasminogen activator inhibitor in patients with acute ischemic stroke: relation to stroke etiology

Recent studies suggest that high plasma levels of tissue-type plasminogen activator (tPA) and its inhibitor (plasminogen activator inhibitor-1, PAI-1) are markers of an increased risk of atherothrombotic ischemic events such as stroke and myocardial infarction. In this prospective study, we measured tPA antigen, PAI-1 antigen and activity, as well as tPA/PAI-1 complex in patients with acute stroke. Stroke subtypes were classified according to the TOAST criteria. From 132 consecutively screened patients, 89 (100%) were enrolled in this study, including 42 patients (47%) with large artery atherosclerosis (LAA), 32 (36%) with small vessel occlusion (SVO), and 15 (17%) with cardioembolism (CE). Nineteen age-matched neurologic patients without manifestations of cerebrovascular disease served as control subjects (CS). Patients with acute stroke had significantly higher plasma levels of tPA antigen (p < 0.001), PAI-1 antigen (p < 0.05) and PAI activity (p < 0.05) than patients in the control group. t-PA antigen, PAI activity and tPA/PAI-1 complex levels were similar regardless of stroke etiology. Only PAI-1 antigen was lower in patients with cardioembolic stroke than in stroke patients with LAA (p < 0.05). Plasma tPA antigen, PAI-1 antigen, and PAI activity are significantly increased in patients with acute ischemic stroke. Except for PAI-1 antigen, this increase appears not to be related to the underlying stroke etiology.

Phosphorylated cis-4-methylsphingosine mimics the mitogenic effect of sphingosine-1-phosphate in Swiss 3T3 fibroblasts

The phosphorylated derivative of sphingosine, sphingosine-1-phosphate, is a short-living metabolite of ultimate ceramide degradation and was shown to act as an intracellular signaling molecule, stimulating cell proliferation in quiescent Swiss 3T3 fibroblasts and inducing the release of calcium from intracellular stores (Zhang, H., Desai, N. N., Olivera, A., Seki, T., Brooker, G., and Spiegel, S. (1991) J. Cell. Biol. 114, 155-167). In the present study, 24-h treatment of Swiss 3T3 fibroblasts with the synthetic sphingosine analogue cis-4-methylsphingosine resulted in proliferation of quiescent Swiss 3T3 fibroblasts that was 3-fold stronger than that of equimolar sphingosine-1-phosphate. The phosphorylated derivative of cis-4-methylsphingosine accumulated drastically in the cells. Simultaneous treatment with the sphingosine kinase inhibitor L-threo-sphinganine reduced both the amount of phosphorylated cis-4-methylsphingosine and cell proliferation induced by this compound by about 50%, indicating that the phosphorylated derivative mediated the proliferative stimulus. The mitogenic effect of cis-4-methylsphingosine was associated with a mobilization of intracellular calcium in Swiss 3T3 fibroblasts that was similar to that induced by sphingosine-1-phosphate. The results demonstrate that the phosphorylated derivative of cis-4-methylsphingosine mimics the previously reported mitogenic action of sphingosine-1-phosphate in Swiss 3T3 cells, and the stronger effect most likely corresponds to the unusual accumulation of this compound.

Hyperinsulinism and cerebral microangiopathy

BACKGROUND AND PURPOSE

High insulin levels are a recognized risk factor for atherosclerosis. Microvascular endothelium is more susceptible to metabolic and mitogenic effects of insulin than large-vessel endothelium. Besides their atherogenic effect, high insulin levels impair fibrinolysis by enhancing plasminogen activator inhibitor-1. We undertook this study to evaluate the hypothesis that elevated serum insulin and C-peptide levels are related to cerebral small-vessel disease rather than large-vessel pathology.

METHODS

One hundred ninety-four consecutive patients presenting with symptomatic cerebrovascular disease were assigned to three subgroups that were differentiated by clinical presentations, brain imaging studies, and extracranial as well as transcranial vascular ultrasound findings: (1) patients with lacunes (n = 20), (2) patients with subcortical arteriosclerotic encephalopathy (n = 35), and (3) patients with strokes due to large-vessel disease (n = 99). Patients who had suffered a cryptogenic (n = 9) or cardioembolic (n = 16) stroke or who showed characteristics of the microangiopathy and macroangiopathy groups (n = 15) were not further evaluated. Thirty patients without manifestations of cerebrovascular disease were also examined. Fasting blood glucose, insulin, and C-peptide levels were determined in all subjects.

RESULTS

There were no significant differences in age or sex among the three groups and control patients. Insulin levels were significantly higher in the lacunar group compared with the subcortical arteriosclerotic encephalopathy group, the macroangiopathy group, and the control patients (median [interquartile range]: 103.8 [198.6], 72.0 [103.2], 66.0 [57.0], and 52.2 [57.0] pmol/L, respectively; all P < .05, Mann-Whitney test). There was a statistically significant difference in insulin concentrations between the microangiopathy group (subcortical arteriosclerotic encephalopathy and lacunes) and the macroangiopathy and control groups (81.0 [110.4], 66.0 [57.0], and 55.2 [57.0] pmol/L, respectively; all P < .05, Mann-Whitney). The same was true for the distribution of C-peptide levels and to a minor extent blood glucose values, but these differences failed to reach statistical significance.

CONCLUSIONS

Elevated insulin levels potentially represent a pathogenetic factor in the development of cerebral small-vessel disease, predominantly in patients presenting with lacunes. Whether this is due solely to atherosclerotic changes of the small penetrating arteries or whether changes in hemorheology are operative as well remains to be evaluated.

Two-sample nonparametric estimation and confidence intervals under truncation

We consider point estimates and confidence intervals for the difference in location or scale between two populations when the observations are subject to truncation. We suggest procedures analogous to those for the complete-sample case. A rigorous justification is presented to support the proposed confidence interval procedure. Finally, some simulations verify the properties of the estimators and confidence intervals. We illustrate the procedure using data on tumor size.

[Current problems in the study of noise effects]

This article deals with three problems. First, to what extent is the equivalent noise level valid? The halving parameter, the A-weighting, the short integration time, the fast modulations of frequency and dynamic qualities of hearing--all these aspects prove to be problematic even today. Secondly, is noise noxious to our health? It is difficult to prove that noise is detrimental to our health; many people are annoyed by noise; however, only particular groups (children, the elderly, the handicapped, people who wear a hearing aid, people with heart disease) are affected as far as health is concerned, and it is these people who require special protection. Thirdly, how harmful is the personal stereo? There are numerous indications that is harmful when not used correctly. Investigations need to be made into the role of the "Walkman" in the environment of young people.

Effect of beta-casomorphins and analogs on insulin release in dogs

Opioid-active substances have been isolated from bovine beta-casein peptone (beta-casomorphin). Since the ingestion of beta-casomorphin-containing foodstuff elicits an increase in postprandial insulin release, the present study was designed to determine the effect of iv infused beta-casomorphins on insulin release. The infusion of beta-casomorphin-7, -5, -4, and -3 did not alter basal insulin secretion. During prestimulation of insulin release with amino acids and glucose the infusion of beta-casomorphin-7, -5, -4, and -3 at a dose of 1 nmol/ kg . h augmented insulin release, whereas at a concentration of 100 nmol/kg . h no further stimulatory effect was observed except for the infusion of beta-casomorphin-4. In comparison, the infusion of morphine elicited a potentiation of insulin release at the lower dose, whereas no effect was observed at the higher infusion rate. Leucine-enkephalin had no effect at the lower dose but elicited an inhibitory effect at the higher rate. The infusion of opiate-active and inactive analogs of beta-casomorphin-4 resulted in a loss of its stimulatory effect, indicating that the full tetrapeptide structure of the molecule is important for its stimulatory activity on beta-cell secretion. All stimulatory and inhibitory effects of the opioid-active substances were blocked by the specific opiate-receptor antagonist naloxone. Additionally, the present data support the concept that beta-cell secretion is stimulated by mu-receptor activation and inhibited by delta-receptor activation. The K-receptor antagonist ethyl-ketocyclazocine did not alter insulin secretion. The fact that iv administered beta-casomorphins stimulate insulin release raises the possibility that ingested food-derived opioid-active substances modulate pancreatic endocrine function also after their absorption, provided the doses employed in the present study reflect physiological concentrations of circulating beta-casomorphins.

Radiology nursing: a new dimension

Radiology departments all over the country are inundated with new technology being introduced into the radiographic market. This more complex environment has created a new role in many radiology departments. The position of radiology patient advocate is somewhat new, but growing in potential for maintaining the quality of patient care being delivered. The nurse in radiology can assist in humanizing the patient's experience. The nurse can also act as a liaison with other professional departments. Finally, the nurse can assist in maintaining and improving the quality of care provided in a radiology department. The department of radiology now, more than ever, needs to consider complementing their staff with a nurse.

[Selective proximal vagotomy without drainage in uncomplicated duodenal ulcer. Technic and frequency of recurrence]

899 cases of slective promimal vagotomy were operated between 1974-1978 in the Surgical University Hospital Erlangen. The underlying disease was in all cases a chronical duodenal ulcer. The primary operative mortality was 0,6%. Intraopeatively measurements to control the sufficiency of the vagotomy Burge and Grassi proved to be necessary. We could verify by endoscopy a recurrence rate of 5,8-16,5% in the 1.-4. postoperative year. Only 58% of the recurrences could be found by x-ray investigations. 75-82% of the patients had a clinically perfect and good result. In patients with a proven recurrent ulcer there was nevertheless a good clinical result in 64%. Clinical results and complaints of the patients are therefore not sufficient as follow-up after selective proximal vagotomy and early detection of a recurrent ulcer. We believe, that one endoscopy per year is necessary.

[Experiences with selective proximal vagotomy in the treatment of chronic duodenal ulcers]

After 138 selective proximal vagotomies--130 of which were performed because of chronic duodenal ulcer--the rate of the postoperative complications was 3,8%, which is very low; the primary lethality was 0,76%. At re-examination 68% of the patients were without complaints; 8% had a recurrent ulcer. Epigastric fulness (6%), dumping (1%) and diarrhea (1%) were rare. Because of our results we believe, that selective proximal vagotomy is the optimal method for the surgical treatment of duodenal ulcer.