Why trust? A mixed-method investigation of the origins and meaning of trust during the COVID-19 lockdown in Denmark

Trust is highlighted as central to effective disease management. During the COVID-19 pandemic, Denmark seemed to embody this understanding. Characterizing the Danish response were high levels of public compliance with government regulations and restrictions coupled with high trust in the government and other members of society. In this article, we first revisit prior claims about the importance of trust in securing compliant citizen behaviour based on a weekly time-use survey that we conducted during the first weeks of the COVID-19 pandemic (2 April-18 May 2020). Analysis of activity episodes, rather than merely self-reported compliance, both reconfirms the importance of institutional trust and nuances prior suggestions of detrimental effects of trust in other citizens. These survey-based results are further augmented through thematic analysis of 21 in-depth interviews with respondents sampled from the survey participants. The qualitative analysis reveals two themes, the first focusing on trust in others in Danish society and the second on the history of trust in Denmark. Both themes are based on narratives layered in cultural, institutional and inter-personal levels and further underline that institutional and social trust are complementary and not countervailing. We conclude by discussing how our analysis suggests pathways towards an increased social contract between governments, institutions and individuals that might be of use during future global emergencies and to the overall functioning of democracies.

Observing many researchers using the same data and hypothesis reveals a hidden universe of uncertainty

This study explores how researchers' analytical choices affect the reliability of scientific findings. Most discussions of reliability problems in science focus on systematic biases. We broaden the lens to emphasize the idiosyncrasy of conscious and unconscious decisions that researchers make during data analysis. We coordinated 161 researchers in 73 research teams and observed their research decisions as they used the same data to independently test the same prominent social science hypothesis: that greater immigration reduces support for social policies among the public. In this typical case of social science research, research teams reported both widely diverging numerical findings and substantive conclusions despite identical start conditions. Researchers' expertise, prior beliefs, and expectations barely predict the wide variation in research outcomes. More than 95% of the total variance in numerical results remains unexplained even after qualitative coding of all identifiable decisions in each team's workflow. This reveals a universe of uncertainty that remains hidden when considering a single study in isolation. The idiosyncratic nature of how researchers' results and conclusions varied is a previously underappreciated explanation for why many scientific hypotheses remain contested. These results call for greater epistemic humility and clarity in reporting scientific findings.

[Medical biostatistics with GMRC Shiny Stats - learning by doing]

Biostatistics are omnipresent in the scientific and medical literature and are an essential skill for any health student. We have developed a practical training tool - GMRC Shiny stats - an interactive application specifically dedicated to medical data statistical analysis. The application has been designed to provide an analysis workflow corresponding to the usual progression of an experienced statistician during data analysis. The most common statistical analyses can be performed (descriptive statistics, inferences according to frequentist methods, survival analyses, correlation, agreement measurements, etc.). GMRC Shiny stats is intuitive and user-friendly and assists students in choosing the most appropriate statistical tests. With all these functionalities, students can learn statistical analysis by doing. Getting involved in the statistical analysis and processing of their own data is likely to improve their biostatistics skills.

Prevalence and characterisation of vocal fold motion impairment (VFMI) in patients with Multiple system atrophy compared with Parkinson's disease

INTRODUCTION

Multiple system atrophy (MSA) is a neurodegenerative disorder in which vocal fold mobility can be affected, sometimes leading to life-threatening situations. Our aim was to know if laryngeal examination could help differentiate MSA from Parkinson's disease (PD).

MATERIALS AND METHODS

Between 2004 to 2014, all consecutive patients diagnosed with probable MSA were included in this retrospective, monocentric study. Flexible laryngoscopy was obtained in 51 MSA patients and compared with 27 patients with Parkinson's disease (PD). Laryngeal muscles EMG was available in 6 MSA patients.

RESULTS

Vocal fold motion impairments (VFMI) was found in 35 (68.6%) MSA patients: 15 (29.4%) had uni- or bilateral vocal fold abnormal movement (VFAM), 13 (25.5%) had uni- or bilateral vocal fold abductor paresis (VFABP), 4 (7.8%) had uni- or bilateral vocal fold adductor paresis (VFADP), 10 (19.6%) had bilateral vocal fold paralysis (BVFP). VFMI was found in 13 PD patients (48.1%) all of whom had VFADP. Presence of BVFP was found associated with stridor (P<0.001) and dysphagia (P=0.002). In all muscles examined in 6 MSA patients, the EMG showed neuropathic patterns.

CONCLUSIONS

Our data support that VFMI may be encountered in two-thirds of MSA with a variable degree of gravity. Laryngological examination should be considered as a supplementary tool for the diagnosis and prognosis of MSA. VFMI in particular VFAM, VFABD and BVFP should be discussed as an additional possible red flag even at an early stage of MSA and could help discriminate MSA from PD.

Décès et limitations thérapeutiques aux urgences : étude rétrospective des pratiques dans un centre hospitalier français pendant quatre ans

Objectifs : Nous avons analysé les caractéristiques médicoadministratives et la prise en charge des patients décédés dans le service d’accueil des urgences (SAU) d’un centre hospitalier français.

Matériels et méthodes : Il s’agissait d’une étude rétrospective observationnelle des patients décédés aux urgences entre janvier 2012 et décembre 2015. Nous avons analysé les procédures de limitation et d’arrêt des thérapeutiques actives (LATA) et comparé les caractéristiques des groupes de patients « LATA » et « Non LATA ».

Résultats : Deux cent trente-deux patients sont décédés au SAU en quatre ans. Vingt pour cent des décès sont survenus très rapidement malgré les soins de réanimation, et 80 % sont survenus après une décision de LATA. Les LATA étaient décidées par un urgentiste seul dans 56 % des cas et avec un délai de réflexion très court : 13 % en préhospitalier et 28 % au cours de la première heure au SAU. Quatorze pour cent des LATA n’étaient pas inscrites dans le dossier médical. Les patients en LATA étaient plus âgés, plus souvent déments, venaient de maison de retraite et étaient adressés pour des motifs plus graves (p < 0,01). Ils ont généralement bénéficié de soins de confort en unité d’hospitalisation de courte durée : antalgiques, hypnotiques et antisécrétoires lorsque cela était nécessaire.

Conclusion : Deux tiers des procédures de LATA ne respectaient pas les recommandations de bonne pratique en termes de collégialité et de traçabilité. Une amélioration des pratiques est possible au SAU par l’élaboration d’une nouvelle procédure de LATA prenant en compte les contraintes de l’urgence.

Luxations aiguës d'épaule : évaluation rétrospective aux urgences et proposition d'un protocole de sédation procédurale

Introduction : Les luxations d'épaule sont des pathologies fréquentes aux urgences, parmi les plus douloureuses et pour lesquelles il n'existe pas de recommandations spécifiques. Elles représentent 45 % de l'ensemble des luxations. L'objectif principal de cette étude était d'analyser la gestion de la douleur dans cette pathologie.

Matériel et méthodes : Nous avons conduit une étude observationnelle, monocentrique et rétrospective colligeant 238 patients ayant consulté aux urgences pour une luxation aiguë d'épaule (01/01/2012-30/04/2015). Les luxations réduites spontanément, les luxations sur prothèse et les luxations chroniques étaient exclues de l'étude.

Résultats : Les luxations aiguës d'épaule étaient majoritairement réduites aux urgences (90 %, IC95 % : [86-94]). Il s'agissait d'une pathologie hyperalgique (Echelle numérique médiane : 8/10, [EIC : 6-9]) touchant plutôt les sujets jeunes (âge médian : 48 ans, EIC : 28-73). Il existait une grande hétérogénéité dans la répartition des antalgiques utilisés, le mélange équimolaire d'oxygène et de protoxyde d'azote (MEOPA) était l'antalgique le plus prescrit (50 % (IC95 % : [42-55])), suivi par le paracétamol (25 %) et le néfopam (15 %). Dans le sous-groupe des luxations compliquées d'une fracture, le MEOPA était également le plus prescrit. La répartition des autres antalgiques était par ailleurs similaire. Enfin, la comparaison entre les deux équipes médicales (urgentiste vs orthopédiste) ne retrouvait aucune différence de prescription en dehors du midazolam davantage utilisé par les urgentistes (16 % vs 4 %, p=0,001).

Conclusion : Il existait une grande hétérogénéité des pratiques et une sous-utilisation d'antalgiques et d'hypnotiques malgré des douleurs importantes dès l'admission. Un chemin clinique visant à améliorer cette prise en charge est proposé afin d'homogénéiser les pratiques.

Intraoperative Pleth Variability Index Is Linked to Delayed Graft Function After Kidney Transplantation

BACKGROUND

Delayed graft function (DGF) is an early postoperative complication of kidney transplantation (KT) predisposing to acute rejection and lower graft survival. Intraoperative arterial hypotension and hypovolemia are associated with DGF. Central venous pressure (CVP) is used to estimate volemia but its reliability has been criticized. Pleth variability index (PVI) is a hemodynamic parameter predicting fluid responsiveness. The aim of this study was to examine the relationship between intraoperative PVI and CVP values and the occurrence of DGF.

METHODS

This was a prospective, noninterventional, observational, single-center study. All consecutive patients with KT from deceased donors were included. Recipients received standard, CVP, and PVI monitoring. Intraoperative hemodynamic parameters were recorded from recipients at 5 time points during KT.

RESULTS

Forty patients were enrolled. There was a poor correlation between PVI and CVP values (r² = 0.003; P = .44). Immediate graft function and DGF patients had similar hemodynamic values during KT, with the exception of PVI values, which were significantly higher in the DGF group. In particular, a PVI >9% before unclamping of the renal artery was the only predictive parameter of DGF in our multivariate analysis (P = .02).

CONCLUSIONS

This study suggests that PVI values >9% during KT are associated with the occurrence of DGF.

Contested Boundaries: Explaining Where Ethnoracial Diversity Provokes Neighborhood Conflict

Concerns about neighborhood erosion and conflict in ethnically di- verse settings occupy scholars, policy makers, and pundits alike; but the empirical evidence is inconclusive. This article proposes the contested boundaries hypothesis as a refined contextual explanation focused on poorly defined boundaries between ethnic and racial groups. The authors argue that neighborhood conflict is more likely to occur at fuzzy boundaries defined as interstitial or transitional areas sandwiched between two homogeneous communities. Edge detection algorithms from computer vision and image processing allow them to identify these boundaries. Data from 4.7 million time- and geo-coded 311 service requests from New York City support their argument: complaints about neighbors making noise, drinking in public, or blocking the driveway are more frequent at fuzzy boundaries rather than crisp, polarized borders. By focusing on the broader sociospatial structure, the contested boundaries hypothesis overcomes the "aspatial" treatment of neighborhoods as isolated areas in research on ethnic diversity.

[Clinicopathological study of purpura: Is a skin biopsy necessary for palpable purpura?]

OBJECTIVE

For many physicians, palpable purpura is synonymous with vasculitis. However, a skin biopsy is almost always performed in common clinical practice in order to confirm the diagnosis. The aim of our study was to assess whether palpable purpura is always indicative of an inflammatory infiltrate in a vessel wall.

PATIENTS AND METHODS

Eighty-seven patients were included in this prospective monocentric study, 45 of whom were presenting a palpable purpura. Patients were classified in two categories: "leukocytoclastic vasculitis" or "other diagnosis". The clinical and histopathological features of patients with a palpable purpura were studied.

RESULTS

The mean age of patients presenting a palpable purpura was 69 years. There were 26 men and 19 women. Of the 43 patients biopsied, 37 were included in the vasculitis group. The sensitivity, specificity, positive predictive value and negative predictive value for a diagnosis of vasculitis in patients with palpable purpura were respectively 82, 65, 86 and 58 %. The Odds ratio was 8.48 (95 % CI, 2.52-31.80; P<0.05).

CONCLUSION

Most of the palpable purpuras examined were indeed related to leukocytoclastic vasculitis. In the remaining cases, biopsy did not contribute to the diagnosis since it only showed purpura without vessel wall inflammation. In our opinion, a skin biopsy is thus not essential where the clinical presentation is typical.

Relational diversity and neighbourhood cohesion. Unpacking variety, balance and in-group size

Ethnic diversity is typically measured by the well-known Hirschman-Herfindahl Index. This paper discusses the merits of an alternative approach, which is in our view better suited to tease out why and how ethnic diversity matters. The approach consists of two elements. First, all existing diversity indices are non-relational. From the viewpoint of theoretical accounts that attribute negative diversity effects to in-group favoritism and out-group threat, it should however matter whether, given a certain level of overall diversity, an individual belongs to a minority group or to the dominant majority. We therefore decompose diversity by distinguishing the in-group share from the diversity of ethnic out-groups. Second, we show how generalized entropy measures can be used to test which of diversity's two basic dimensions matters most: the variety of groups, or the unequal distribution (balance) of the population over groups. These measures allow us to test different theoretical explanations against each other, because they imply different expectations regarding the effects of in-group size, out-group variety, and out-group balance. We apply these ideas in an analysis of various social cohesion measures across 55 German localities and show that both in-group size and out-group diversity matter. For the native majority as well as for persons of immigration background, the variety component of diversity seems to be more decisive than has formerly been acknowledged. These findings provide little support for group threat and in-group favoritism as the decisive mechanisms behind negative diversity effects, and are most in line with the predictions of theories that emphasize coordination problems, asymmetric preferences, and network closure.

Characterization of GSK'963: a structurally distinct, potent and selective inhibitor of RIP1 kinase

Necroptosis and signaling regulated by RIP1 kinase activity is emerging as a key driver of inflammation in a variety of disease settings. A significant amount has been learned about how RIP1 regulates necrotic cell death through the use of the RIP1 kinase inhibitor Necrostatin-1 (Nec-1). Nec-1 has been a transformational tool for exploring the function of RIP1 kinase activity; however, its utility is somewhat limited by moderate potency, off-target activity against indoleamine-2,3-dioxygenase (IDO), and poor pharmacokinetic properties. These limitations of Nec-1 have driven an effort to identify next-generation tools to study RIP1 function, and have led to the identification of 7-Cl-O-Nec-1 (Nec-1s), which has improved pharmacokinetic properties and lacks IDO inhibitory activity. Here we describe the characterization of GSK′963, a chiral small-molecule inhibitor of RIP1 kinase that is chemically distinct from both Nec-1 and Nec-1s. GSK′963 is significantly more potent than Nec-1 in both biochemical and cellular assays, inhibiting RIP1-dependent cell death with an IC₅₀ of between 1 and 4 nM in human and murine cells. GSK′963 is >10 000-fold selective for RIP1 over 339 other kinases, lacks measurable activity against IDO and has an inactive enantiomer, GSK′962, which can be used to confirm on-target effects. The increased in vitro potency of GSK′963 also translates in vivo, where GSK′963 provides much greater protection from hypothermia at matched doses to Nec-1, in a model of TNF-induced sterile shock. Together, we believe GSK′963 represents a next-generation tool for examining the function of RIP1 in vitro and in vivo, and should help to clarify our current understanding of the role of RIP1 in contributing to disease pathogenesis.

Can competing diversity indices inform us about why ethnic diversity erodes social cohesion? A test of five diversity indices in Germany

An ever-growing number of studies investigates the relation between ethnic diversity and social cohesion, but these studies have produced mixed results. In cross-national research, some scholars have recently started to investigate more refined and informative indices of ethnic diversity than the commonly used Hirschman-Herfindahl Index. These refined indices allow to test competing theoretical explanations of why ethnic diversity is associated with declines in social cohesion. This study assesses the applicability of this approach for sub-national analyses. Generally, the results confirm a negative association between social cohesion and ethnic diversity. However, the competing indices are empirically indistinguishable and thus insufficient to test different theories against one another. Follow-up simulations suggest the general conclusion that the competing indices are meaningful operationalizations only if a sample includes: (1) contextual units with small and contextual units with large minority shares, as well as (2) contextual units with diverse and contextual units with polarized ethnic compositions. The results are thus instructive to all researchers who wish to apply different diversity indices and thereby test competing theories.

Anterior pituitary cell networks

Both endocrine and non-endocrine cells of the pituitary gland are organized into structural and functional networks which are formed during embryonic development but which may be modified throughout life. Structural mapping of the various endocrine cell types has highlighted the existence of distinct network motifs and relationships with the vasculature which may relate to temporal differences in their output. Functional characterization of the network activity of growth hormone and prolactin cells has revealed a role for cell organization in gene regulation, the plasticity of pituitary hormone output and remarkably the ability to memorize altered demand. As such, the description of these endocrine cell networks alters the concept of the pituitary from a gland which simply responds to external regulation to that of an oscillator which may memorize information and constantly adapt its coordinated networks' responses to the flow of hypothalamic inputs.

Prospective, randomized comparison of laryngeal tube and laryngeal mask airway in pediatric patients

BACKGROUND

While reports of the use of laryngeal mask airway (LMA)-Classic in great patient numbers are available, data on the use of the laryngeal tube (LT) in this age group is limited. The two devices are compared in a prospective randomized trial to evaluate success rates and quality of airway seal.

METHODS

Sixty children, aged 2-8 years, scheduled for elective surgical interventions were randomized to be ventilated with LMA or LT. Standardized anesthesia was induced with fentanyl and propofol. Number of insertion attempts, time until first tidal volume and intraoperative tidal volumes, and peak pressures were recorded. Airway leak pressure was measured with cuff pressure adjusted to 60 cmH(2)O.

RESULTS

Demographic data were comparable, average age in the LMA/LT group was 5.2 +/- 1.9/5.3 +/- 1.9 years. Insertion was successful in 29 of 30 patients in the LMA group (second attempt 8) and in all patients in the LT group (second attempt 3). Time until first tidal volume for LMA/LT was 23.1 +/- 7.3/19.2 +/- 8.6 s (P < 0.05). Peak airway pressures for LMA and LT were 15.3 +/- 3.4 and 17.1 +/- 4.0 cmH(2)O (P < 0.05) with tidal volumes of 10.2 +/- 2.2 and 10.2 +/- 1.9 ml.kg(-1), airway leak pressure was 19.2 +/- 8.6 cmH(2)O for LMA and 26.3 +/- 7.3 cmH(2)O for LT (P < 0.001).

CONCLUSION

Insertion success rate is high with both LMA and LT in the age group studied. The airway leak pressure, serving as an estimate to judge quality of airway seal, is higher with the LT.

Signaling through a novel domain of gp130 mediates cell proliferation and activation of Hck and Erk kinases

Interleukin-6 (IL-6) induces the activation of the Src family kinase Hck, which is associated with the IL-6 receptor beta-chain, gp130. Here we describe the identification of an "acidic" domain comprising amino acids 771 to 811 of gp130 as a binding region for Hck, which mediates proliferative signaling. The deletion of this region of gp130 (i.e., in deletion mutant d771-811) resulted in a significant reduction of Hck kinase activity and cell proliferation upon stimulation of gp130 compared to wild-type gp130. In addition, d771-811 disrupted the growth factor-stimulated activation of Erk and the dephosphorylation of Pyk2. Based on these findings, we propose a novel, acidic domain of gp130, which is responsible for the activation of Hck, Erk, and Pyk2 and signals cell proliferation upon growth factor stimulation.

Improving the well-being of elderly patients via community pharmacy-based provision of pharmaceutical care: a multicentre study in seven European countries

OBJECTIVE

This study aimed to measure the outcomes of a harmonised, structured pharmaceutical care programme provided to elderly patients (> or =65 years of age) by community pharmacists in a multicentre international study performed in 7 European countries.

DESIGN AND SETTING

The study was a randomised, controlled, longitudinal, clinical trial with repeated measures performed over an 18-month period. A total of 104 intervention and 86 control pharmacy sites participated in the research and 1290 intervention patients and 1164 control patients were recruited into the study.

MAIN OUTCOME MEASURES AND RESULTS

A general decline in health-related quality of life over time was observed in the pooled data; however, significant improvements were achieved in patients involved in the pharmaceutical care programme in some countries. Intervention patients reported better control of their medical conditions as a result of the study and cost savings associated with pharmaceutical care provision were observed in most countries. The new structured service was well accepted by intervention patients and patient satisfaction with the services improved during the study. The pharmacists involved in providing pharmaceutical care had a positive opinion on the new approach, as did the majority of general practitioners surveyed. The positive effects appear to have been achieved via social and psychosocial aspects of the intervention, such as the increased support provided by community pharmacists, rather than via biomedical mechanisms.

CONCLUSIONS

This study is the first large-scale, multicentre study to investigate the effects of pharmaceutical care provision by community pharmacists to elderly patients. Future research methodology and implementation will be informed by the experience gained from this challenging trial.

Health care costs associated with escalation of drug treatment in type 2 diabetes mellitus

The cost of different intensities of therapy in HMO patients with type 2 diabetes mellitus was studied. Health care utilization data from 1995 were obtained for 12,200 registrants from the Kaiser Permanente Northwest Diabetes Registry who had type 2 diabetes mellitus. The data were used to determine costs associated with the escalation of antidiabetic therapies in persons with type 2 diabetes mellitus. The total annual costs (in 1993 dollars) associated with no drug therapy, a sulfonylurea only, metformin, a sulfonylurea plus insulin, and insulin alone were $4400, $4187, $4838, $8856, and $7365, respectively. Per patient total costs were higher for patients who had received antidiabetic therapy in 1995 or previously than for those who had not ($5303 versus $4365) and for patients who had received insulin therapy than for those who had not ($7379 versus $4117). Macrovascular complications accounted for 62-89% of the cost associated with inpatient treatment of diabetes-related complications. The total cost of treating patients with type 2 diabetes mellitus at an HMO increased as antidiabetic therapies escalated.

Modifiable and nonmodifiable factors associated with osteoporosis in postmenopausal women: results from the Third National Health and Nutrition Examination Survey, 1988-1994

We wished to study the relationship between modifiable and nonmodifiable factors that were correlated with osteoporosis using a national sample of women aged 50 years and older who have never been on hormone replacement therapy (HRT). We used a cross-sectional study design with a nationally representative sample with a detailed clinical examination and a home interview. Between 1988 and 1994, 1953 postmenopausal women who had never been on HRT, aged 50 years and older, were examined as part of the Third National Health and Nutrition Examination Survey (NHANES III). Mexican Americans and non-Hispanic blacks were oversampled to produce reliable estimates for these groups. Bone density measurements of four proximal femur sites were assessed by using x-ray absorptiometry (DEXA). A DEXA measurement at any single femur site indicated osteoporosis if it was >2.5 standard deviations (SD) below the reference mean of 20--29-year-old women. The study demonstrated that numerous factors, both modifiable and nonmodifiable, were significantly related to the prevalence of osteoporosis. The modifiable factors identified were participation in physical activity (three to five times per week) and body mass index (BMI). Nonmodifiable factors included age, race, and mother's history. With the aging population, osteoporosis is a growing concern for the medical community. It is suggested that educational strategies are needed to increase awareness of factors that contribute to maintaining bone health among postmenopausal women. Emphasis may be placed on maintaining regular physical activity.

The natural history of hepatitis C virus infection: host, viral, and environmental factors

CONTEXT

Hepatitis C virus (HCV) infection may resolve (viral clearance), persist without complications, or cause end-stage liver disease (ESLD). The frequency and determinants of these outcomes are poorly understood.

OBJECTIVE

To assess the incidence and determinants of viral clearance and ESLD among persons who acquired HCV infection from injection drug use.

DESIGN AND SETTING

Community-based prospective cohort study with enrollment in 1988-1989 and a median follow-up of 8.8 years.

SUBJECTS

A total of 1667 persons aged 17 years or older with a history of injection drug use and an HCV antibody-positive test result during follow-up.

MAIN OUTCOME MEASURES

Viral clearance was assessed in a subset of 919 patients and defined as failure to detect HCV RNA in at least 2 consecutive samples collected 5 or more months apart. End-stage liver disease was assessed at semiannual visits and by review of medical records and death certificates and defined by the presence of ascites, esophageal varices, or hepatic encephalopathy, or when ESLD was stated as a cause of death.

RESULTS

Viral clearance was observed in 90 persons who were compared with 722 with persistent viremia, while the viremia of 107 was not resolved. Viral clearance occurred more often in nonblacks (adjusted odds ratio [OR], 5.15; 95% confidence interval [CI], 2.60-10.17) and those not infected with human immunodeficiency virus (HIV) (adjusted OR, 2.19; 95% CI, 1.26-3.47). Forty cases of ESLD were observed throughout follow-up (incidence, 3.1 per 1000 person-years). In a multivariate model, risk of ESLD was higher for persons aged 38 years or older at enrollment (adjusted relative incidence, 3.67; 95% CI, 1.96-6.88) and who reported ingestion of more than 260 g of alcohol per week (adjusted relative incidence, 3.60; 95% CI, 1.73-7.52). Of 210 patients without ESLD randomly selected for biopsy, only 2 had cirrhosis.

CONCLUSIONS

Our results indicate that although HCV infection can be self-limited or associated with ESLD, the majority of adults have persistent viremia without clinically demonstrable liver disease. Further research is needed to explain the less frequent clearance of HCV infection among black persons and to improve utilization of treatment for those infected in the context of injection drug use. JAMA. 2000;284:450-456

Orientation specificity of the Lactococcus lactis Chi site

BACKGROUND

In Escherichia coli, the Chi sequence modulates the activity of RecBCD, a powerful double-stranded (ds) DNA exonuclease/helicase. Chi attenuates RecBCD exonuclease activity and stimulates homologous recombination in an orientation-dependent manner. ChiEc is frequent and over-represented on its genome, which is thought to be related to its role in dsDNA break repair. We previously identified a Chi-like sequence (referred to as ChiLl) and an exonuclease/helicase in the Gram-positive bacterium Lactococcus lactis. ChiLl and RexAB are functional analogues of ChiEc and RecBCD.

RESULTS

We report that ChiLl attenuates RexAB exonuclease activity and stimulates homologous recombination in an orientation-dependent manner. Analysis of ChiLl distribution on the L. lactis chromosome reveals that ChiLl is frequent, highly over-represented, and oriented with respect to the direction of replication.

CONCLUSION

Our results show that a single orientation of ChiLl interacts with RexAB. The active orientation is preferentially found on the replication leading strand of the L. lactis genome, consistent with a primary role of ChiLl in repair of dsDNA breaks at the replication fork. We propose that orientation-dependence of Chi activity and over-representation of Chi sequences on bacterial genomes may be conserved properties of exonuclease/helicase-Chi couples. Other properties of the Chi sequence distribution on the genomes might reflect more specific characteristics of each couple and of the host.

[Evaluation of the usefulness of the liver for transplantation based on 26 multiorgan harvests]

This study is aimed at the clinical and morphological criteria of estimation of the liver harvested for transplantation. In the period from January 1996 to May 1997 our team obtained 26 livers at the multi-organ harvesting. Most of the donors were young people after the trauma of central nervous system. The liver was harvested according to the principles of Starzl's fast method with the successive preparation on the "cold table". The donor's clinical status was estimated, as well as appearance, density and colour of the organ, quality of perfusion with UW solution In 23 cases the histological examination of the harvested organ allowed to estimate the degree of steatosis, hepatocyte necrosis, vacuolar degeneration and other abnormalities. In 3 cases the graft was estimated only by means of macroscopic examination.

RESULTS

As a result of clinical and histological findings 8 organs were considered as unsuitable for transplantation. In one case the histological findings were the contraindication despite the satisfactory macroscopic appearance of the organ 15 organs were successfully transplanted, proving the conformity of clinical and histological criteria. In 4 livers (15%) the abnormalities of arterial supply were found.

CONCLUSIONS

Clinical and pathomorphological estimation of the harvested liver is adequate to it's suitability for transplantation, advisable for the centres initiating the liver transplantation program. Detailed analysis of the donor's clinical status and laboratory data and competent macroscopic estimation of the harvested liver allow the experienced surgeon to resign from the routine histological verification, which might be necessary in doubtful cases only.

Analysis of 1.9 Mb of contiguous sequence from chromosome 4 of Arabidopsis thaliana

The plant Arabidopsis thaliana (Arabidopsis) has become an important model species for the study of many aspects of plant biology. The relatively small size of the nuclear genome and the availability of extensive physical maps of the five chromosomes provide a feasible basis for initiating sequencing of the five chromosomes. The YAC (yeast artificial chromosome)-based physical map of chromosome 4 was used to construct a sequence-ready map of cosmid and BAC (bacterial artificial chromosome) clones covering a 1.9-megabase (Mb) contiguous region, and the sequence of this region is reported here. Analysis of the sequence revealed an average gene density of one gene every 4.8 kilobases (kb), and 54% of the predicted genes had significant similarity to known genes. Other interesting features were found, such as the sequence of a disease-resistance gene locus, the distribution of retroelements, the frequent occurrence of clustered gene families, and the sequence of several classes of genes not previously encountered in plants.

[Angiopeptin versus placebo for reductin of restenosis after PTCA treatment. A randomized, double-blind study]

Angiopeptin, a somatostatin analogue, inhibits intimal hyperplasia after (percutaneous transluminal coronary angioplasty) (PTCA) in several animal models. This pilot study sought to determine the effect of subcutaneous infusion of angiopeptin on clinical events and restenosis in patients undergoing successful PTCA. One hundred and twelve patients were randomized to receive continuous subcutaneous angiopeptin (750 micrograms/day) or placebo infusion from the day before PTCA and for the following four days in a double-blind study. Eighty patients had a successful PTCA, and 75 of these patients with 94 lesions underwent angiography 6 +/- 2 months after PTCA. All 112 patients underwent clinical follow-up at 12 months. The 12-month event rate (death, myocardial infarction, coronary artery bypass grafting and re-PTCA) was reduced from 34% to 25% (p = 0.30) by angiopeptin by intention to treat analysis. Restenosis (> or = 50% diameter stenosis) was significantly reduced in lesions treated with angiopeptin (12% vs 40%; p = 0.003). Late lumen loss was also significantly reduced after angiopeptin treatment (0.12 +/- 0.46 mm vs 0.52 +/- 0.64 mm; p = 0.003). In conclusion, continuous subcutaneous angiopeptin infusion for five days tended to decrease clinical events and restenosis after PTCA.

Elastic light-scattering measurements of single biological cells in an optical trap

We have developed an instrument for determination of the angular light scattering of beads and biological cells. The instrument uses radiation pressure for levitation of particles inside a cuvette. The setup consists of two 780-nm diode lasers in a vertical double-beam trapping configuration. In the horizontal direction a weakly focused 633-nm probe beam is used to illuminate the trapped particle. One can detect scattered light over the range of from - 150 to 150 deg with an angular resolution of 0.9 deg using an avalanche photodiode. With this setup light scattering from polystyrene beads was measured, and the obtained scattering patterns were compared with theoretical scattering patterns from Lorenz-Mie theory. The results show that the setup is stable, gives reproducible patterns, and qualitatively agrees with the calculations. Trapping of biological cells is more difficult than trapping of beads, because smaller forces result from smaller refractive indices. We present an angular scattering pattern measured from a human lymphocyte measured from 20 to 60 deg.

[Orthotopic liver transplantation in a patient with primary biliary cirrhosis]

In December 1994 an orthotopic liver transplantation was performed in a 46-year old female patient with liver failure due to primary biliary cirrhosis. The patient was discharged on the 31-st postoperative day. The graft was obtained at the multi-organ harvesting. The results of the donor's biochemical tests and the histological estimation of the graft tissue allowed to prognose a successful postoperative course.

Randomized double-blind Scandinavian trial of angiopeptin versus placebo for the prevention of clinical events and restenosis after coronary balloon angioplasty

Angiopeptin, a somatostatin analogue, inhibits intimal hyperplasia after percutaneous transluminal coronary artery balloon angioplasty (PTCA) in several animal models. This pilot study sought to determine the effect of subcutaneous infusion of angiopeptin on clinical events and restenosis in patients undergoing successful PTCA. One hundred twelve patients were randomized to receive continuous subcutaneous angiopeptin (750 micrograms/day) or placebo infusion from the day before PTCA and for the following 4 days in a double-blind study. An additional subcutaneous injection of 375 micrograms of angiopeptin or saline was given immediately before PTCA. Eighty patients had a successful PTCA, and 75 of these patients with 94 lesions underwent angiography 6 +/- 2 months after PTCA. All 112 patients underwent a 12-month clinical follow-up examination. Age, sex, smoking, diabetes, hypertension, hyperlipidemia, and morphologic features of stenosis were similar in both groups. The hierarchical 12-month event rate (death, myocardial infarction, coronary artery bypass grafting, and repeated PTCA) was reduced from 34% to 25% (p = 0.30) by angiopeptin by intention-to-treat analysis. Restenosis (> or = 50% diameter stenosis) was significantly reduced in lesions treated with angiopeptin (12% vs 40%; p = 0.003). Late lumen loss also was significantly reduced after angiopeptin treatment (0.12 +/- 0.46 mm vs 0.52 +/- 0.64 mm; p = 0.003). In conclusion, continuous subcutaneous angiopeptin infusion for 5 days tended to decrease clinical events and restenosis after PTCA.

Long-term effects of angiopeptin treatment in coronary angioplasty. Reduction of clinical events but not angiographic restenosis. European Angiopeptin Study Group

BACKGROUND

Angiopeptin is a cyclic octapeptide analogue of somatostatin that has been shown to limit myointimal thickening of arteries in balloon injury models and to restore the vasodilating response to acetylcholine. A randomized, double-blind placebo controlled trial was conducted to assess the effect of angiopeptin in restenosis prevention after percutaneous transluminal coronary angioplasty (PTCA).

METHODS AND RESULTS

Patients received a continuous infusion of either placebo or angiopeptin subcutaneously 6 to 24 hours before PTCA and for 4 days after PTCA (3 mg per 24 hours before PTCA followed by 6 mg per 24 hours after PTCA and for the remaining period). A 1.5-mg bolus dose of placebo or angiopeptin was given at PTCA. Aspirin (acetylsalicylic acid, 150 mg/d) was administered throughout the study period. Coronary angiograms obtained before and after PTCA and at 6-month follow-up were subjected to computerized quantification. Clinical follow-up was performed after 12 months. Primary clinical end points were death, myocardial infarction, coronary artery bypass surgery, or repeat PTCA. In total, 553 patients with 742 lesions were randomized. Clinical follow-up was available for all 553 patients. Angiopeptin decreased the clinical events during 12 months of follow-up from 36.4% in the placebo-treated group to 28.4% in the angiopeptin-treated patients (P = .046). Quantitative angiography after PTCA and at follow-up was available in 423 of 455 patients who underwent successful PTCA. The minimal lumen diameter at follow-up was 1.52 +/- 0.64 mm in the angiopeptin-treated group compared with 1.52 +/- 0.64 mm in the placebo-treated patients (P = .96). The late losses were 0.31 +/- 0.59 and 0.30 +/- 0.62 mm (P = .81) and the restenosis rates (> 50% diameter stenosis at follow-up) were 36% and 37% (P = .85) in the angiopeptin- and placebo-treated groups, respectively.

CONCLUSIONS

In this study, angiopeptin significantly decreased the incidence of clinical events, principally the rate of revascularization procedures. In contrast, no significant effect was seen on angiographic variables.

Multiple dose pharmacokinetics, safety, and effects on faecal microflora, of cefepime in healthy volunteers

In a randomized, double-blind, placebo-controlled study in 12 healthy volunteers pharmacokinetics, safety and impact on the faecal microflora of cefepime were determined. For eight days eight volunteers received cefepime 1000 mg bd by constant infusion over 30 min, four volunteers received placebo. Concentrations of cefepime in serum and urine were measured by bioassay and HPLC. The correlation between the two methods was good and the bioassay results were used for pharmacokinetic calculations. The faecal flora was analysed twice before the study, twice during the study and four times after cefepime administration. There were no significant differences in the pharmacokinetic parameters between days 1 and 8. The following values (mean +/- S.D.) represent day 1. The maximum concentration of 72.69 +/- 12.2 mg/L immediately after infusion decreased to 0.56 +/- 0.17 mg/L after 12 h. The mean 12 h recovery in urine was 93.69 +/- 2.14%. Pharmacokinetic parameters based on an open two-compartment model were as follows (mean +/- S.D.): area under the curve, 142.65 +/- 18.35 mg.h/L; elimination half-life 110.3 +/- 8.3 min; steady state volume of distribution 16.0 +/- 1.9 L/70 kg; total clearance, 107.0 +/- 16.0 mL/min; renal clearance 103.0 +/- 15.2 mL/min. No accumulation was observed during the eight day study period with cefepime at this dosage; trough levels on days 2-7 ranged from 0.52 +/- 0.26 mg/L to 0.90 +/- 0.33 mg/L. In the cefepime treated group the following side-effects were noted: headache (5), fatigue (4), nausea/stomach ache (2), soft stool (2), transient scotoma (1). Side-effects in the placebo group were: headache (2) fatigue (3), nausea/stomach-ache (1), soft stool (2) and photophobia (1). During cefepime administration a decrease in the number of Escherichia coli and bifidobacteria in faeces was observed, whereas Bacteroides spp. and clostridia showed a slight increase. The numbers of faecal bacteria returned to normal 20 to 48 days after the study was completed.

Accelerated in vitro degradation of CCK-58 in blood and plasma of patients with acute pancreatitis

Proteases released into the circulation during acute pancreatitis may hydrolyse circulating peptide hormones leading to altered regulatory functions. Cholecystokinin is a major regulator of postprandial gut function; stimulating pancreatic enzyme secretion, gallbladder contraction and diminishing food intake. Cholecystokinin-58 is the largest and most abundant form of this hormone in acid extracts of human intestine, and major amounts are released into the circulation after feeding. In order to test whether cholecystokinin-58 is degraded more rapidly due to the increased circulating of enzymes, this peptide was added to blood and plasma of patients with acute pancreatitis and incubated for various time intervals. The in vitro half life of cholecystokinin-58 was 10 +/- 1 minutes (mean +/- SE) in plasma and 11 +/- 1 min in blood from patients with acute pancreatitis, about four fold lower than the half life in plasma of healthy volunteers; 45 +/- 5 min. Degradation of cholecystokinin-58 produced immunoreactive forms of cholecystokinin that eluted in the positions of cholecystokinin-8 and cholecystokinin-33/39. We conclude that acute pancreatitis increases the degradation of CCK molecules.

Perfluorinated analogues of poison ivy allergens. Synthesis and skin tolerogenic activity in mice

3-(Tridecafluoroundecyl)catechol (8) and 3-(nonafluoropentadecyl)catechol (9), perfluorinated analogues of pentadecylcatechol (PDC), a constituent of poison ivy, have been synthesized. These compounds were nonsensitizers in mice. Compounds 8 and 9, however, were elicitors of allergic contact dermatitis in PDC-sensitized animals. Moreover, compound 9 exhibited tolerogenic properties to sensitization by poison ivy allergens, i.e. mice pretreated with perfluorinated compounds could not be sensitized to PDC.

Molecular variants of cholecystokinin after endogenous stimulation in humans: a time study

The time-dependent release of molecular variants of cholecystokinin (CCK) into the circulation was studied before and 1, 2, and 4 h after a test meal in six healthy volunteers. At each time period, 100 ml of blood were drawn in a manner to inhibit CCK degradation. Plasma was formed and CCK concentrated by Sep-Pak C18 cartridge chromatography. Molecular variants of CCK and gastrin were well separated from each other by high-performance liquid chromatography (HPLC). Molecular forms of CCK and gastrin were measured by radioimmunoassay using an antibody that requires the presence of the carboxyl-terminal phenylalanine amide for full recognition, implying that biologically active forms were detected. HPLC elution positions of gastrin forms were determined using a gastrin-specific antibody. Chromatographic separation of CCK from gastrin forms was complete, allowing separate integration of gastrin and CCK forms. Therefore no subtraction of gastrin-like immunoreactivity from CCK-like immunoreactivity (CCK-LI) was necessary and CCK-LI could be directly determined. Peaks of CCK-LI were integrated in the column eluates and the plasma concentrations were calculated. Total plasma CCK-LI rose from a value of 2.4 +/- 0.6 pM before the test meal to 6.4 +/- 0.8, 6.6 +/- 0.9, and 5.8 +/- 1.2 pM 1, 2, and 4 h postprandially. The major molecular forms released into the circulation eluted on HPLC in the position of CCK-58 and CCK-39 (which coelutes with CCK-33). Minor amounts were detected in the position of CCK-8. There was no significant difference in the relative proportions of the molecular forms released at the different time periods.(ABSTRACT TRUNCATED AT 250 WORDS)

Characterization of the major form of cholecystokinin in human intestine: CCK-58

Acid extracts of human intestines obtained from surgical samples or from organ donors contain cholecystokinin (CCK) immunoreactivity. From surgical samples, extracted and eluted quickly, greater than 75% of the CCK immunoreactivity eluted in the same region as purified canine CCK-58 during analytical reverse-phase high-pressure liquid chromatography (HPLC). A major portion of the CCK immunoreactivity from donor intestinal extracts also eluted in this region. This immunoreactivity has been purified from human intestinal extracts by a series of several reverse-phase and cation-exchange chromatographies. Amino acid and microsequence analysis showed that this immunoreactivity is human CCK-58. Tryptic digestion of purified human CCK-58 produced another immunoreactive form that eluted in the position of CCK-8 during analytical reverse-phase HPLC. The immunoreactivity of the trypsin-digested material was 2.6-fold higher than that of an identical sample of CCK-58 incubated without trypsin. Thus the carboxyl-terminal antibody used for radioimmunoassay cross-reacts greater than twofold less with human CCK-58. This diminished cross-reactivity would lead to an underestimation of the relative proportions of CCK-58 in tissue and plasma extracts. If CCK-58 is the major circulating form this diminished cross-reactivity would also lead to underestimations of the circulating levels of total CCK. Determination of human CCK-58 structure confirms that one of the major components of human CCK that expresses biological activity is CCK-58.

Structural characterization of canine PYY

PYY was purified from canine colonic mucosa by sequential steps of reverse phase HPLC and ion-exchange FPLC. Microsequence, amino acid and mass spectral analyses of the purified peptide and its tryptic fragments were consistent with the structure: YPAKPEAPGEDASPEELSRYYASLRHYLNLVTRQRY-amide. Canine PYY(1-36) has the identical sequence as porcine and rat PYY but differs from human PYY at position 3, with Ala instead of Ile, and position 18, with Ser instead of Asn. A smaller form, PYY(3-36), was also purified and characterized. It may differ in its biological activity from the intact peptide and could act as a partial antagonist or agonist of PYY(1-36).