Processes occurring in the NaCMC/glauconite suspension under the cold plasma treatment. Influence of plasma on adsorptive and stabilizing properties of the system

The paper presents the studies on the processes at the interface of the colloidal suspensions composed of clay mineral - glauconite (GT) and polysaccharide - sodium carboxymethyl cellulose (NaCMC) with the cold plasma treatment (CPT). The surface composition and chemical binding in NaCMC and GT changes are determined by means of FTIR and XPS (both methods detected the incorporation of oxygen-related functional groups). Moreover, the additional information about both the textural properties and morphological changes on the surfaces before and after CPT are studied using the BET, CHN, SEM HRTEM and STEM-EDS methods. The elemental mapping and scanning electron microscope imaging confirmed the NaCMC adsorption on GT (carbon mapping) and proved the GT surface lost its "house of card structure" after the CPT. As follows the CPT causes the protonation of NaCMC and the polymer cross-linking whereas the GT sample is more oxidized. Moreover, it was found that a significant improvement in the GT/NaCMC system stability and the NaCMC adsorption on the GT surface were a result of the CPT. The obtained data could be used for the colloidal stability of polymer/solid suspensions, thus providing new opportunities for the chemical industry; particularly for preparation of new functionalized materials.

Mixed-methods study to assess an intervention for healthier lifestyles in primary healthcare

Background

Smoking, physical inactivity, low fruit and vegetable consumption, and obesity are common in Kosovo. The Accessible Quality Healthcare project is implementing a primary healthcare intervention that entails nurse-guided motivational counselling to facilitate lifestyle behaviour change. This study assesses the uptake of counselling and the impact on health behaviours and participants’ stages of health behaviour change as well as describes experiences and perceived benefits of motivational counselling.

Methods

Study participants (n = 907) were recruited from 12 municipalities participating in the Kosovo Non-Communicable Disease Cohort study. For the quantitative study, data on lifestyle behaviours, use of counselling, and stages for behavioural change were used. For the qualitative study, in-depth interviews were conducted with 26 cohort participants who had undergone motivational counselling.

Results

Motivational counselling was received by only 22% of the eligible participants in the intervention municipalities. Unhealthy behaviours remain high even in persons who underwent counselling (of whom 13% are smokers; 86% are physically inactive; 93% with inadequate fruit and vegetable consumption; 61% are obese). According to the qualitative study results, the participants that received counselling were very satisfied with the services but requested additional services such as group physical activity sessions and specialized services for smoking cessation.

Conclusions

More tailored and additional primary healthcare approaches in accordance with patients’ views need to be considered for the motivational counselling intervention to reach patients and efficiently facilitate lifestyle behaviour change.

Key messages

• The following tailored approaches are suggested: a) strengthened referral mechanism b) specialized services for smoking cessation; c) delivery of group physical activity sessions.

• More tailored and additional primary health care approaches in accordance with patients’ views need to be considered for the motivational counselling intervention.

Prevalence of restless legs syndrome in professional cyclists

Introduction

Restless legs syndrome (RLS) is a sleep disorder affecting a significant part of general population. Clinically RLS is characterized by abnormal sensations of irresistible urge to move legs, becoming worse at night, and frequently causing insomnia. Consequences of RLS include daytime dysfunction, depressed mood, anxiety and decreased quality of life.

Objectives

Determine prevalence of RLS in professional cyclists.

Aims

The aim of this study was to examine the prevalence of RLS in professional cyclists. According to our knowledge this is the first research of RLS in professional cyclists.

Methods

A total of 43 professional cyclists were asked to complete 4-item questionnaire based on IRLSSG Diagnostic Criteria for RLS. Data from questionnaire was compared to antropometric measurements, epidemiologic data, age of starting trainings and total years of professional performance.

Results

The results indicated that prevalence of RLS in professional cyclists is 14% and is higher than expected in this age group. We found statistically significant relationship between RLS and age (P < 0,001) and years of experience as a professional cyclist (P < 0,001). Results revealed no significant differences between genders (Table 1).

Table 1 

Conclusions

RLS seems to be a common problem in professional cyclists. It can affect sport performance. Future efforts to estimate the influence of RLS on professional sport performance should be considered.

Disclosure of interest

The authors have not supplied their declaration of competing interest.

Homogenization of tissues via picosecond-infrared laser (PIRL) ablation: Giving a closer view on the in-vivo composition of protein species as compared to mechanical homogenization

Posttranslational modifications and proteolytic processing regulate almost all physiological processes. Dysregulation can potentially result in pathologic protein species causing diseases. Thus, tissue species proteomes of diseased individuals provide diagnostic information. Since the composition of tissue proteomes can rapidly change during tissue homogenization by the action of enzymes released from their compartments, disease specific protein species patterns can vanish. Recently, we described a novel, ultrafast and soft method for cold vaporization of tissue via desorption by impulsive vibrational excitation (DIVE) using a picosecond-infrared-laser (PIRL). Given that DIVE extraction may provide improved access to the original composition of protein species in tissues, we compared the proteome composition of tissue protein homogenates after DIVE homogenization with conventional homogenizations. A higher number of intact protein species was observed in DIVE homogenates. Due to the ultrafast transfer of proteins from tissues via gas phase into frozen condensates of the aerosols, intact protein species were exposed to a lesser extent to enzymatic degradation reactions compared with conventional protein extraction. In addition, total yield of the number of proteins is higher in DIVE homogenates, because they are very homogenous and contain almost no insoluble particles, allowing direct analysis with subsequent analytical methods without the necessity of centrifugation.

Biological significance

Enzymatic protein modifications during tissue homogenization are responsible for changes of the in-vivo protein species composition. Cold vaporization of tissues by PIRL-DIVE is comparable with taking a snapshot at the time of the laser irradiation of the dynamic changes that occur continuously under in-vivo conditions. At that time point all biomolecules are transferred into an aerosol, which is immediately frozen.

Biological Psychiatry Congress 2015

<p><strong>List of Abstract Titles and authors:<br /></strong></p><p><strong>1. Psychosis: A matter of mental effort?</strong></p><p>M Borg, Y Y van der Zee, J H Hsieh, H Temmingh, D J Stein, F M Howells</p><p><strong>2.In search of an affordable, effective post-discharge intervention: A randomised control trial assessing the influence of a telephone-based intervention on readmissions for patients with severe mental illness in a developing country</strong></p><p><strong></strong>U A Botha, L Koen, M Mazinu, E Jordaan, D J H Niehaus</p><p><strong>3. The effect of early abstinence from long-term methamphetamine use on brain metabolism using 1H-magnetic resonance spectro-scopy (1H-MRS)</strong></p><p>A Burger, S Brooks, D J Stein, F M Howells</p><p><strong>4. The effect of <em>in utero exposure </em>to methamphetamine on brain metabolism in childhood using 1H-magnetic resonance spectroscopy (1H-MRS)</strong></p><p>A Burger, A Roos, M Kwiatkowski, D J Stein, K A Donald, F M Howells</p><p><strong>5. A prospective study of clinical, biological and functional aspects of outcome in first-episode psychosis: The EONKCS Study</strong></p><p><strong></strong>B Chiliza, L Asmal, R Emsley</p><p><strong>6. Stimulants as cognitive enhancers - perceptions v. evidence in a very real world</strong></p><p><strong></strong>H M Clark</p><p><strong>7. Pharmacogenomics in antipsychotic drugs</strong></p><p><strong></strong>Ilse du Plessis</p><p><strong>8. Serotonin in anxiety disorders and beyond</strong></p><p><strong></strong>Ilse du Plessis</p><p><strong>9. HIV infection results in ventral-striatal reward system hypo-activation during cue processing</strong></p><p><strong></strong>S du Plessis, M Vink, J A Joska, E Koutsilieri, A Bagadia, D J Stein, R Emsley</p><p><strong>10. Disease progression in schizophrenia: Is the illness or the treatment to blame?</strong></p><p>R Emsley, M J Sian</p><p><strong>11. Serotonin transporter variants play a role in anxiety sensitivity in South African adolescents</strong></p><p> S M J Hemmings, L I Martin, L van der Merwe, R Benecke, K Domschke, S Seedat</p><p><strong>12. Iron deficiency in two children diagnosed with multiple sclerosis: Report on whole exom sequencing</strong></p><p><strong></strong>S Janse van Rensburg, R van Toorn, J F Schoeman, A Peeters, L R Fisher, K Moremi, M J Kotze</p><p><strong>13. Benzodiazepines: Practical pharmacokinetics</strong></p><p><strong></strong>P Joubert</p><p><strong>14. What to consider when prescribing psychotropic medications</strong></p><p><strong></strong>G Lippi</p><p><strong>15. Current prescribing practices for obsessive-compulsive disorder in South Africa: Controversies and consensus</strong></p><p><strong></strong>C Lochner, L Taljaard, D J Stein</p><p><strong>16. Correlates of emotional and behavioural problems in children with preinatally acquired HIV in Cape Town, South Africa</strong></p><p><strong></strong>K-A Louw, N Phillips, JIpser, J Hoare</p><p><strong>17. The role of non-coding RNAs in fear extinction</strong></p><p><strong></strong>S Malan-Muller, L Fairbairn, W M U Daniels, M J S Dashti, E J Oakleley, M Altorfer, J Harvey, S Seedat, J Gamieldien, S M J Hemmings</p><p><strong>18. An analysis of the management og HIV-mental illness comorbidity at the psychiatric unit of the Dr George Mukhari Academic Hospital</strong></p><p><strong></strong>M L Maodi, S T Rataemane, T Kyaw</p><p><strong>19. The identification of novel genes in anxiety disorders: A gene X environment correlation and interaction study</strong></p><p><strong></strong>N W McGregor, J Dimatelis, S M J Hemmings, C J Kinnear, D J Stein, V Russel, C Lochner</p><p><strong>20. Collaborations between conventional medicine and traditional healers: Obstacles and possibilities</strong></p><p><strong></strong>G Nortje, S Seedat, O Gureje</p><p><strong>21. Thought disorder and form perception: Relationships with symptoms and cognitive function in first-episode schizophrenia</strong></p><p>M R Olivier, R Emsley</p><p><strong>22. Investigating the functional significance of genome-wide variants associated with antipsychotic treatment response</strong></p><p><strong></strong>E Ovenden, B Drogemoller, L van der Merwe, R Emsley, L Warnich</p><p><strong>23. The moral and bioethical determinants of "futility" in psychiatry</strong></p><p><strong></strong>W P Pienaar</p><p><strong>24. Single voxel proton magnetic resonance spectroscopy (1H-MRS) and volumetry of the amylgdala in social anxiety disorder in the context of early developmental trauma</strong></p><p>D Rosenstein, A T Hess, J Zwart, F Ahmed-Leitao, E Meintjies, S Seedat</p><p><strong>25. Schizoaffective disorder in an acute psychiatric unit: Profile of users and agreement with Operational Criteria (OPCRIT)</strong></p><p><strong></strong>R R Singh, U Subramaney</p><p><strong>26. The right to privacy and confidentiality: The ethics of expert diagnosis in the public media and the Oscar Pistorius trial</strong></p><p><strong></strong>C Smith</p><p><strong>27. A birth cohort study in South Africa: A psychiatric perspective</strong></p><p>D J Stein</p><p><strong>28. 'Womb Raiders': Women referred for observation in terms of the Criminal Procedures Act (CPA) charged with fetal abduction and murder</strong></p><p><strong></strong>U Subramaney</p><p><strong>29. Psycho-pharmacology of sleep wake disorders: An update</strong></p><p>R Sykes</p><p><strong>30. Refugee post-settlement in South Africa: Role of adjustment challenges and family in mental health outcomes</strong></p><p><strong></strong>L Thela, A Tomita, V Maharaj, M Mhlongo, K Jonathan</p><p><strong>31. Dstinguishing ADHD symptoms in psychotic disorders: A new insight in the adult ADHD questionnaire</strong></p><p>Y van der Zee, M Borg, J H Hsieh, H Temmingh, D J Stein, F M Howells</p><p><strong>32. Oscar Pistorius ethical dilemmas in a trial by media: Does this include psychiatric evaluation by media?</strong></p><p>M Vorster</p><p><strong>33. Genetic investigation of apetite aggression in South African former young offenders: The involvement of serotonin transporter gene</strong></p><p>K Xulu, J Somer, M Hinsberger, R Weierstall, T Elbert, S Seedat, S Hemmings</p><p><strong>34. Effects of HIV and childhood trauma on brain morphemtry and neurocognitive function</strong></p><p>G Spies, F Ahmed-Leitao, C Fennema-Notestine, M Cherner, S Seedat</p><p><strong>35. Measuring intentional behaviour normative data of a newly developed motor task battery</strong></p><p><strong></strong>S Bakelaar, J Blampain, S Seedat, J van Hoof, Y Delevoye-Turrel</p><p><strong>36. Resilience in social anxiety disorder and post-traumatic stress disorder in the context of childhood trauma</strong></p><p>M Bship, S Bakelaar, D Rosenstein, S Seedat</p><p><strong>37. The ethical dilemma of seclusion practices in psychiatry</strong></p><p>G Chiba, U Subramaney</p><p><strong>38. Physical activity and neurological soft signs in patients with schizophrenia</strong></p><p>O Esan, C Osunbote, I Oladele, S Fakunle, C Ehindero</p><p><strong>39. A retrospective study of completed suicides in the Nelson Mandela Bay Metropolitan Area from 2008 to 2013 - preliminary results</strong></p><p><strong></strong>C Grobler, J Strumpher, R Jacobs</p><p><strong>40. Serotonin transporter variants play a role in anxiety sensitivity in South African adolescents</strong></p><p><strong></strong>S M J Hemmings, L I Martin, L van der Merwe, R Benecke, K Domschke, S Seedat</p><p><strong>41. Investigation of variants within antipsychotic candidate pharmacogenes associated with treatment outcome</strong></p><p>F Higgins, B Drogmoller, G Wright, L van der Merwe, N McGregor, B Chiliza, L Asmal, L Koen, D Niehaus, R Emsley, L Warnich</p><p><strong>42. Effects of diet, smoking and alcohol consumption on disability (EDSS) in people diagnosed with multiple sclerosis</strong></p><p>S Janse van Rensburg, W Davis, D Geiger, F J Cronje, L Whati, M Kidd, M J Kotze</p><p><strong>43. The clinical utility of neuroimaging in an acute adolescnet psychiatric inpatient population</strong></p><p><strong></strong>Z Khan, A Lachman, J Harvey</p><p><strong>44. Relationships between childhood trauma (CT) and premorbid adjustment (PA) in a highly traumatised sample of patients with first-episode schizophrenia (FES</strong>)</p><p>S Kilian, J Burns, S Seedat, L Asmal, B Chiliza, S du Plessis, R Olivier, R Emsley</p><p><strong>45. Functional and cognitive outcomes using an mTOR inhibitor in an adolescent with TSC</strong></p><p>A Lachman, C van der Merwe, P Boyes, P de Vries</p><p><strong>46. Perceptions about adolescent body image and eating behaviour</strong></p><p><strong></strong>K Laxton, A B R Janse van Rensburg</p><p><strong>47. Clinical relevance of FTO rs9939609 as a determinant of cardio-metabolic risk in South African patients with major depressive disorder</strong></p><p>H K Luckhoff, M J Kotze</p><p><strong>48. Childhood abuse and neglect as predictors of deficits in verbal auditory memory in non-clinical adolescents with low anxiety proneness</strong></p><p>L Martin, K Martin, S Seedat</p><p><strong>49. The changes of pro-inflammatory cytokines in a prenatally stressed febrile seizure animal model and whether <em>Rhus chirindensis</em> may attenuate these changes</strong></p><p><strong></strong>A Mohamed, M V Mabandla, L Qulu</p><p><strong>50. Influence of TMPRSS6 A736v and HFE C282y on serum iron parameters and age of onset in patients with multiple sclerosis</strong></p><p><strong></strong>K E Moremi, M J Kotze, H K Luckhoff, L R Fisher, M Kidd, R van Toorn, S Janse van Rensburg</p><p><strong>51. Polypharmacy in pregnant women with serious mental illness</strong></p><p>E Thomas, E du Toit, L Koen, D Niehaus</p><p><strong>52. Infant attachment and maternal depression as predictors of neurodevelopmental and behavioural outcomes at follow-up</strong></p><p>J Nothling, B Laughton, S Seedat</p><p><strong>53. Differences in abuse, neglect and exposure to community violence in adolescents with and without PTSD</strong></p><p><strong></strong>J Nothling, S Suliman, L Martin, C Simmons, S Seedat</p><p><strong>54. Assessment of oxidative stress markers in children with autistic spectrum disorders in Lagos, Nigeria</strong></p><p><strong></strong>Y Oshodi, O Ojewunmi, T A Oshodi, T Ijarogbe, O F Aina, J Okpuzor, O C F E A Lesi</p><p><strong>55. Change in diagnosis and management of 'gender identity disorder' in pre-adolescent children</strong></p><p>S Pickstone-Taylor</p><p><strong>56. Brain network connectivity in women exposed to intimate partner violence</strong></p><p>A Roos, J-P Fouche, B Vythilingum, D J Stein</p><p><strong>57. Prolonged exposure treatment for PTSD in a Third-World, task-shifting, community-based environment</strong></p><p>J Rossouw, E Yadin, I Mbanga, T Jacobs, W Rossouw, D Alexander, S Seedat</p><p><strong>58. Contrasting effects of early0life stress on mitochondrial energy-related proteins in striatum and hippocampus of a rat model of attention-deficit/ hyperactivity disorder</strong></p><p><strong></strong>V Russell, J Dimatelis, J Womersley, T-L Sterley</p><p><strong>59. Attention-deficit hyperactivity disorder in adults: A South African perspective</strong></p><p>R Schoeman, M de Klerk, M Kidd</p><p><strong>60. Cognitive function in women with HIV infection and early-life stress</strong></p><p>G Spies, C Fennema-Notestine, M Cherner, S Seedat</p><p><strong>61. Changes in functional connectivity networks in bipolar disorder patients after mindfulness-based cognitic therapy</strong></p><p>J A Starke, C F Beckmann, N Horn</p><p><strong>62. Post-traumatic stress disorder, overweight and obesity: A systematic review and meta-analysis</strong></p><p><strong></strong>S Suliman, L Anthonissen, J Carr, S du Plessis, R Emsley, S M J Hemmings, C Lochner, N McGregor L van den Heuvel, S Seedat</p><p><strong>63. The brain and behaviour in a third-trimester equivalent animal model of fetal alcohol spectrum disorders</strong></p><p>P C Swart, C B Currin, J J Dimatelis, V A Russell</p><p><strong>64. Irritability Assessment Model (IAM) to monitor irritability in child and adolescent psychiatric disorders.</strong></p><p>D van der Westhuizen</p><p><strong>65. Outcome of parent-adolescent training in chilhood victimisation: Adaptive functioning, psychosocial and physiological variables</strong></p><p>D van der Westhuizen</p><p><strong>66. The effect of ketamine in the Wistar-Kyoto and Sprague Dawley rat models of depression</strong></p><p>P J van Zyl, J J Dimatelis, V A Russell</p><p><strong>67. Investigating COMT variants in anxiety sensitivity in South African adolescents</strong></p><p>L J Zass, L Martin, S Seedat, S M J Hemmings</p><p> </p><p> </p><p> </p><p> </p><p> </p><p> </p><p> </p><p> </p><p> </p><p> </p><p> </p><p> </p><p><strong><br /></strong></p><p> </p><p> </p><p> </p><p> </p><p> </p><p> </p><p> </p><p> </p><p> </p><p> </p><p> </p>

[PSA screening 2013: background and perspectives]

In the healthcare political discussions on treatment measures, the controversy over prostate-specific antigen (PSA) screening has taken a leading role in comparison to, for example the relatively undisputed role of breast and colon screening. This has fortunately led to an in-depth critical analysis of the available data. One advantage is the benefit on survival which increases with longer follow-up observation times. When carrying out studies the quantitative extent of this benefit can become obscured by prescreening, prevalent screening, lack of compliance, contamination and healthy screen bias. Nevertheless, the European randomized screening study of prostate cancer (ERSPC) study, for example, showed sufficient statistical power to confirm a screening benefit after 9 or 11 years (evidence level A). However, even for prostate cancer the internal problems of preventive medicine of overdiagnosis and overtherapy are also partially dependent on the age range of the screening population and the screening frequency (28-52%). Unnecessary deficits in the quality of life reduce the benefit of survival in these patients. By using a PSA fine tuning and risk stratification, approximately one third of diagnoses and therapies can be avoided. Additionally, the active surveillance of tumors unsuitable for treatment together with an improved quality of therapy should become of greater importance.

Cost-effectiveness of prostate cancer screening: a simulation study based on ERSPC data

BACKGROUND

The results of the European Randomized Study of Screening for Prostate Cancer (ERSPC) trial showed a statistically significant 29% prostate cancer mortality reduction for the men screened in the intervention arm and a 23% negative impact on the life-years gained because of quality of life. However, alternative prostate-specific antigen (PSA) screening strategies for the population may exist, optimizing the effects on mortality reduction, quality of life, overdiagnosis, and costs.

METHODS

Based on data of the ERSPC trial, we predicted the numbers of prostate cancers diagnosed, prostate cancer deaths averted, life-years and quality-adjusted life-years (QALY) gained, and cost-effectiveness of 68 screening strategies starting at age 55 years, with a PSA threshold of 3, using microsimulation modeling. The screening strategies varied by age to stop screening and screening interval (one to 14 years or once in a lifetime screens), and therefore number of tests.

RESULTS

Screening at short intervals of three years or less was more cost-effective than using longer intervals. Screening at ages 55 to 59 years with two-year intervals had an incremental cost-effectiveness ratio of $73000 per QALY gained and was considered optimal. With this strategy, lifetime prostate cancer mortality reduction was predicted as 13%, and 33% of the screen-detected cancers were overdiagnosed. When better quality of life for the post-treatment period could be achieved, an older age of 65 to 72 years for ending screening was obtained.

CONCLUSION

Prostate cancer screening can be cost-effective when it is limited to two or three screens between ages 55 to 59 years. Screening above age 63 years is less cost-effective because of loss of QALYs because of overdiagnosis.

Production and Characterization of Fine-dispersed Mixtures of Liquid Crystalline with Conventional Polymers

By investigation of adhesion following the harmonic mean method after Wu a suitable pair out of seven liquid crystalline (LCP) and conventional polymers was established in order to produce a LCP-matrix compound. Using a bidirectional piston mixer with a steel wire mesh with mesh size of 63 μm, 5% of the picked out PHB-PET copolymer was finely dispersed into the PET matrix polymer in the molten state. As a result a dispersion of the initial volume of the LCP granules of 1 mm3 into small particles of 0.5 to 1.0 μm3 as well as a very uniform local distribution was achieved which can be considered as an argument for the compatibility of the selected pair and as a confirmation of the usefulness of the preceding investigations of adhesion.

Mass spectral characterization of peptide transmitters/hormones in the nervous system and neuroendocrine organs of the American lobster Homarus americanus

The American lobster Homarus americanus is a decapod crustacean with both high economic and scientific importance. To facilitate physiological investigations of peptide transmitter/hormone function in this species, we have used matrix-assisted laser desorption/ionization Fourier transform mass spectrometry (MALDI-FTMS), matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) and nanoscale liquid chromatography coupled to electrospray ionization quadrupole time-of-flight tandem mass spectrometry (nanoLC-ESI-Q-TOF MS/MS) to elucidate the peptidome present in its nervous system and neuroendocrine organs. In total, 84 peptides were identified, including 27 previously known H. americanus peptides (e.g., VYRKPPFNGSIFamide [Val(1)-SIFamide]), 23 peptides characterized previously from other decapods, but new to the American lobster (e.g., pQTFQYSRGWTNamide [Arg(7)-corazonin]), and 34 new peptides de novo sequenced/detected for the first time in this study. Of particular note are a novel B-type allatostatin (TNWNKFQGSWamide) and several novel FMRFamide-related peptides, including an unsulfated analog of sulfakinin (GGGEYDDYGHLRFamide), two myosuppressins (QDLDHVFLRFamide and pQDLDHVFLRFamide), and a collection of short neuropeptide F isoforms (e.g., DTSTPALRLRFamide and FEPSLRLRFamide). Our data also include the first detection of multiple tachykinin-related peptides in a non-brachyuran decapod, as well as the identification of potential individual-specific variants of orcokinin and orcomyotropin-related peptide. Taken collectively, our results not only expand greatly the number of known H. americanus neuropeptides, but also provide a framework for future studies on the physiological roles played by these molecules in this commercially and scientifically important species.

The fluoride cleavable 2-(cyanoethoxy)methyl (CEM) group as reversible 3'-O-terminator for DNA sequencing-by-synthesis - synthesis, incorporation, and cleavage

A new and promising sequencing technology called sequencing-by-synthesis (SBS) enables fast determination of DNA sequences. 2'-Deoxynucleotides containing the (2-cyanoethoxy)methyl (CEM) group at the 3'-O-position are potential reversible terminators for the SBS technology. Herein we describe the synthesis, the incorporation by several polymerases, and the cleavage of this 3'-O-blocking group using 3'-O-CEM-thymidinyl-5'-O-triphosphate 7 as an example.

Prostate cancer screening: results of a prospective trial in Canton Aargau, Switzerland

INTRODUCTION

Prostate cancer is the most commonly diagnosed cancer in Swiss men and the second leading cause of cancer related death among them (e.g. CH: 1,267 in year 1998). With the population at risk constantly growing these absolute numbers are expected to further increase. While there is no question that aggressive treatment of localised tumour is required for definitive cure of prostate cancer, the application of screening for early stage disease remains controversial. Since 1998 the Clinic of Urology in Kantonsspital Aarau has participated in the ERSPC (European Randomised Study of Screening for Prostate Cancer) study, which is designed to provide data on prostate cancer screening within a prospective randomised controlled setting.

METHODS

Men aged between 55 and 70 years were enrolled in the study. From n = 18,361 men invited by a letter to participate, 7,124 (38.8%) agreed and gave their informed consent to be randomised in either a PSA measurement (n = 3,562, group 1) or a control group (n = 3,562, group 2). Men in group 1 with a PSA level ?3.0 ng/ml, n = 372 (10.5%) then underwent ultrasound guided transrectal sextant biopsy of the prostate.

RESULTS

Prostate cancer was detected at presentation in every fourth man biopsied (n = 89). Neither the free-to-total PSA ratio nor the PSA density could significantly spare biopsies while sustaining a high sensitivity level. The overall cancer detection rate amounted to 2.5% in PSA tested men. In 7% (n = 5) distant disease was already present. 93% of men with clinically organ confined disease underwent prostatectomy (n = 59) or radiotherapy (n = 22), whilst only (n = 3) chose to follow a policy of watchful waiting. In 92% the histology of the prostatectomy specimens revealed aggressive cancer characteristics according to the criteria of Epstein et al.

CONCLUSIONS

Although the clinically relevant tumour characteristics and the relatively low cancer detection rate of 2.5% (less than the lifetime mortality risk of 3% and the morbidity risk of 8%) seem to justify screening in terms of adequate diagnosis and treatment, follow-up until 2008 is needed to prove the benefit in mortality for the prostate cancer screening group over the control group. Furthermore, information from the ongoing ERSPC study is needed in order to assess uncertainties i.e. the degree of overdiagnosis caused by repeated screening and the quality of life adjusted gain in life years. For daily practice a "PSA grey zone" of 4-10 ng/ml can no longer be postulated as only 70% of men in this range presented with organ confined disease. Once the PSA level exceeds 4.0 ng/ml. prostate biopsy should be performed immediately.

Prostate cancer screening: results of a prospective trial in Canton Aargau, Switzerland

INTRODUCTION

Prostate cancer is the most commonly diagnosed cancer in Swiss men and the second leading cause of cancer related death among them (e.g. CH: 1,267 in year 1998). With the population at risk constantly growing these absolute numbers are expected to further increase. While there is no question that aggressive treatment of localised tumour is required for definitive cure of prostate cancer, the application of screening for early stage disease remains controversial. Since 1998 the Clinic of Urology in Kantonsspital Aarau has participated in the ERSPC (European Randomised Study of Screening for Prostate Cancer) study, which is designed to provide data on prostate cancer screening within a prospective randomised controlled setting.

METHODS

Men aged between 55 and 70 years were enrolled in the study. From n = 18,361 men invited by a letter to participate, 7,124 (38.8%) agreed and gave their informed consent to be randomised in either a PSA measurement (n = 3,562, group 1) or a control group (n = 3,562, group 2). Men in group 1 with a PSA level ?3.0 ng/ml, n = 372 (10.5%) then underwent ultrasound guided transrectal sextant biopsy of the prostate.

RESULTS

Prostate cancer was detected at presentation in every fourth man biopsied (n = 89). Neither the free-to-total PSA ratio nor the PSA density could significantly spare biopsies while sustaining a high sensitivity level. The overall cancer detection rate amounted to 2.5% in PSA tested men. In 7% (n = 5) distant disease was already present. 93% of men with clinically organ confined disease underwent prostatectomy (n = 59) or radiotherapy (n = 22), whilst only (n = 3) chose to follow a policy of watchful waiting. In 92% the histology of the prostatectomy specimens revealed aggressive cancer characteristics according to the criteria of Epstein et al.

CONCLUSIONS

Although the clinically relevant tumour characteristics and the relatively low cancer detection rate of 2.5% (less than the lifetime mortality risk of 3% and the morbidity risk of 8%) seem to justify screening in terms of adequate diagnosis and treatment, follow-up until 2008 is needed to prove the benefit in mortality for the prostate cancer screening group over the control group. Furthermore, information from the ongoing ERSPC study is needed in order to assess uncertainties i.e. the degree of overdiagnosis caused by repeated screening and the quality of life adjusted gain in life years. For daily practice a "PSA grey zone" of 4-10 ng/ml can no longer be postulated as only 70% of men in this range presented with organ confined disease. Once the PSA level exceeds 4.0 ng/ml. prostate biopsy should be performed immediately.

[PSA-screening for prostate cancer--yes or no?]

Prostate cancer is a mayor health care problem, especially in the industrialised countries of the Western world. At this time it is the second most common cancer reason for death (CH: 1500 men/year) which will even get more importance in the future by demographic developments. While there is no doubt that in individuals early detection of organ confined disease with localised treatment the prostate cancer can be eradicated and individual men be cured there are uncertainties whether mass screening a population will contribute to reducing prostate cancer related mortality. Its value has not been proved definitively by prospective randomised controlled studies. Most of Medical Societies recommend a "well informed" decision by family physicians, where the men between 50-70 years know about the benefits and harms including: risk of cancer, diagnostic procedures, therapeutic consequences and possible side effects. After agreement of early detection a biopsy has to be done directly above a PSA level of 4.0 ng/ml or a suspicious digital rectal examination. A PSA "grey zone" 4-10 ng/ml can not further be postulated. The ratio of free/total PSA gives no support to prolong biopsy in this moment, because an elevated benign prostate with a higher production of free PSA can mask the tumor in the peripheral zone. Results of the ERSPC and the PLCO trials are expected to give information about the benefits and harms of mass screening in 2006/8.

Features and preliminary results of prostate cancer screening in Canton Aargau, Switzerland

OBJECTIVE

To report the results from Switzerland's participation in the ERSPC from 1998; importantly, epidemiological data showed that Switzerland has one of the highest rates of morbidity and mortality from prostate cancer in the world. The local study protocol was accepted by the ethical committee and after the successful pilot study phase, the centre joined the ERSPC.

SUBJECTS AND METHODS

From September 1998 to June 2003 10 300 men accepted an invitation for the study and were then randomized 1:1 into an active screening arm (assessed by testing prostate-specific antigen, PSA) or a control group (no intervention). The re-screening interval is 4 years and is ongoing (beginning in September 2002). The study protocol includes offering a prostate biopsy when the total PSA is >3.0 ng/mL (the main study protocol in agreement with ERSPC requirements) or when the total PSA is 1-3 ng/mL and the free-to-total PSA ratio <20% (side study protocol).

RESULTS

During the first 3 years of screening 3562 men aged 55-70 years were screened; 395 (11.1%) of all participants had a total PSA of >3 ng/mL and 251 (7.4%) were eligible for the side-study. In all, 599 (17.2%) of 3562 accepted a prostate biopsy (93% of 646); 120 cases of prostate cancer were detected (3.4% detection rate). The incidence was 2.5% in main study group (positive predictive value, PPV, 24%) and 0.9% in side study group (PPV 13.6%). In radical prostatectomy specimens the cancers were mostly 'significant' (92% in main study group and 87% in side-study group).

CONCLUSIONS

A randomized screening study for prostate cancer is feasible in Switzerland. A longer follow-up is needed to address within the ERSPC the primary hypothesis (that there will be a reduction in mortality in the active screening arm) and to determine the level of over/under-diagnosis and over/undertreatment in the active screening and control arms, respectively.

The accuracy of codon recognition by polypeptide release factors

The precision with which individual termination codons in mRNA are recognized by protein release factors (RFs) has been measured and compared with the decoding of sense codons by tRNA. An Escherichia coli system for protein synthesis in vitro with purified components was used to study the accuracy of termination by RF1 and RF2 in the presence or absence of RF3. The efficiency of factor-dependent termination at all sense codons differing from any of the three stop codons by a single mutation was measured and compared with the efficiency of termination at the three stop codons. RF1 and RF2 discriminate against sense codons related to stop codons by between 3 and more than 6 orders of magnitude. This high level of accuracy is obtained without energy-driven error correction (proofreading), in contrast to codon-dependent aminoacyl-tRNA recognition by ribosomes. Two codons, UAU and UGG, stand out as hotspots for RF-dependent premature termination.

Inversion of in situ synthesized oligonucleotides: improved reagents for hybridization and primer extension in DNA microarrays

Oligonucleotides synthesized in array format suffer from contamination by truncated species. We have developed a method to invert DNA molecules in situ after completed synthesis. Reactive functions at the 5'-ends of the oligonucleotides are permitted to react with functions on the support before the 3'-ends are released, in effect reversing the orientation of full-length oligonucleotides, while any 5'-truncated molecules are lost. This strategy serves both to purify in situ synthesized reagents and to reorient the oligonucleotides, causing them to expose free 3'-hydroxyls. In situ inverted oligonucleotides can be used in assays based on DNA polymerase-assisted extension of immobilized primers, and we demonstrate their utility in minisequencing and in pyrosequencing.

A case of the subacute brainstem encephalitis

A case of brainstem encephalitis of undetermined etiology is reported in 66-year-old woman who had a sudden onset of illness with left abducens palsy, nystagmus and ataxia. The symptoms progressed to complete paralysis of eye movements, dysphagia and left hemiparesis with generalized hyperreflexia. Examination of CSF, CT scan and MRI of the brain were normal. The patient died 4 months after onset of disease. Neuropathologic study disclosed in the brainstem numerous perivascular and nodular inflammatory cell infiltrations composed predominantly of lymphocytes T and B. Most intensive inflammation concerned midbrain and pontine tegmentum and to a lesser degree medulla oblongata, pontine nuclei and cerebellar nuclei. Basal ganglia, cerebral and cerebellar cortex were unaffected. Neuropathological finding was reminiscent of brainstem encephalitides related to viral infection or to paraneoplastic syndrome. However, HSV-1, EBV, and CMV antigens were not detected by immunohistochemistry, as well as evidences of malignancy were not present in this case.

Seven-color time-resolved fluorescence hybridization analysis of human papilloma virus types

Identification of human papilloma virus (HPV) types is important in order to determine the risk of cervical carcinoma in women. This requires a technique to probe individual samples for multiple virus specificities. Here we describe simultaneous multicolor analysis of amplification products for any of seven amplified HPV types 16, 18, 31, 33, 35, 39, and 45, associated with cancer of the cervix. A seminested polymerase chain reaction was performed in a single tube using a biotinylated inner primer. Sets of amplification products, immobilized on a 96-pronged manifold solid support, were rendered single stranded and probed with a mix of seven type-specific, differentially labeled oligonucleotides. These probes contained 10 or 20 lanthanide chelates at the 5' ends with seven distinct combinations of europium, terbium, and samarium ions. The seven viral strains were correctly identified by time-resolved fluorescence measurement of the specifically hybridized probes. Using this assay format, simultaneous detection of any of seven or even more target variants is possible.

Padlock probes reveal single-nucleotide differences, parent of origin and in situ distribution of centromeric sequences in human chromosomes 13 and 21

Chromosome centromeres, composed of repeated DNA sequences, orchestrate the correct segregation of chromatids in cell division. We have examined the centromeres of human chromosomes 13 and 21 by studying the distribution, in situ, of two alpha satellite sequences that differ in a single nucleotide position. This was possible using padlock probes, oligo-nucleotides that can be ligated into circles upon target recognition. The segregation of individual 13 and 21 homologues in a family was followed by monitoring of the signals from two differentially labelled probes, specific for either sequence variant. A characteristic arrangement of the repeat motifs in three separate spots, oriented transverse to the length axis of the metaphase chromosomes and bilaterally symmetric, indicates that only parts of the detected regions are involved in the centromeric region, joining the sister chromatids before anaphase.

Synthesis of full-length oligonucleotides: cleavage of apurinic molecules on a novel support

The synthesis of oligodeoxynucleotides is marred by several problems that contribute to the formation of defective molecules. This in turn seriously limits the usefulness of such reagents in DNA diagnostics, molecular cloning, DNA structural analysis and in antisense therapy. In particular, depurination reactions during the cyclical steps of synthesis lead to strand scission during cleavage of the completed molecules from the support. Here we present a remedy to this problem: a novel disiloxyl linkage that connects oligonucleotides to the support withstands reaction conditions that allow the removal of the 5' parts of any depurinated molecules. This ensures that all molecules that preserve the 5' protecting group when cleaved from the support will have both correct 3'- and 5'-ends. We demonstrate the application of the support for synthesis of padlock probe molecules.

Detecting Genes with Ligases

The combination of synthetic oligonucleotide probes and DNA ligases is central to several recently developed genetic assays. Among the advantages of ligase-mediated gene detection is that ligation of probe pairs provides highly specific detection of unique DNA sequences in genomic samples. The technique also allows for convenient distinction between sequence variants, since mismatched bases at the junction of the probe pair prevent ligation. Moreover, the circumstance that two probes are joined into one molecule can be exploited for detection in several ways, for instance by observing the change in probe size upon ligation. Alternatively, a detectable function on one probe can be demonstrated to become linked to a retrievable function on another one through ligation. Ligation products can also be recruited as templates for subsequent ligation reactions in powerful amplification schemes. So-called padlock probes lock to their targets by encircling them, remaining in place even after denaturing washes. Here, we will describe two ligase-mediated assays: one that serves to monitor the presence of common sequence variants in amplified samples of genomic DNA and another that is suitable to detect localized gene sequences.

Human biodistribution, dosimetry and clinical use of technetium(III)-99m-Q12

Technetium(III)-99m-Q12, trans-(1,2-bis(dihydro-2,2,5,5-tetramethyl- 3(2H)furanone-4-methyleneimino)ethane)bis(tris(3-methoxy-1-propyl) - phosphine)technetium(III)-99m, is a nonreducible complex of Tc(III) which is herein evaluated as a myocardial perfusion imaging agent.

METHODS

The biodistribution and dosimetry of 99mTc-Q12 were assessed in 10 normal volunteers, while its potential clinical use was evaluated in 70 patients.

RESULTS

Safety parameters measured up to 24 hr postinjection demonstrate no clinically significant drug-related adverse reactions. Technetium(III)-99m-Q12 exhibits good heart uptake (2.2% injected dose at 1 hr postinjection under resting conditions) and no detectable myocardial washout or redistribution up to 5 hr postinjection. The biodistribution is characterized by very rapid hepatobiliary clearance which allows effective myocardial imaging at times as short as 15 min postinjection. Blood and plasma clearances and myocardial uptake are rapid, while lung uptake is minimal. The heart-to-lung and heart-to-liver ratios are higher at stress than at rest, independent of the time elapsed between injection and image acquisition, and independent of whether the patient is fasted or fed after tracer administration. A preliminary correlation shows that 46/47 patients with angiographically demonstrated CAD also have perfusion defects demonstrated by 99mTc-Q12.

CONCLUSIONS

On the basis of the studies reported herein, 99mTc-Q12 appears to be a promising myocardial perfusion imaging agent.

Padlock probes: circularizing oligonucleotides for localized DNA detection

Nucleotide sequence information derived from DNA segments of the human and other genomes is accumulating rapidly. However, it frequently proves difficult to use such short DNA segments to identify clones in genomic libraries or fragments in blots of the whole genome or for in situ analysis of chromosomes. Oligonucleotide probes, consisting of two target-complementary segments, connected by a linker sequence, were designed. Upon recognition of the specific nucleic acid molecule the ends of the probes were joined through the action of a ligase, creating circular DNA molecules catenated to the target sequence. These probes thus provide highly specific detection with minimal background.

Solid-phase synthesis of chelate-labelled oligonucleotides: application in triple-color ligase-mediated gene analysis

Oligonucleotides labelled with detectable groups are essential tools in gene detection. We describe here the synthesis of pyrimidine deoxynucleotide-building blocks, modified at their C-5 position with a protected form of a strongly chelating agent. These reagents can be used to introduce multiple metal ions into oligodeoxynucleotides during standard oligonucleotide synthesis. The chelating functions form strongly fluorescent complexes with europium ions, characterized by a wide separation between the excitation and emission spectra. Moreover, the long decay time of the fluorescence permits sensitive time-resolved fluorescence measurements. The chelates also have the stability required to function in triple-color assays involving europium, samarium, and terbium ions. We demonstrate the application of these reagents for ligase-based gene analysis reactions.

Europium-labeled oligonucleotide hybridization probes: preparation and properties

A chemical method for labeling of oligonucleotide probes with europium chelates is presented. A modified deoxycytidine phosphoramidite is used to introduce multiple reactive amino groups to the oligonucleotide during the synthesis phase. Upon deprotection and purification of the modified oligonucleotide, an isothiocyanate derivative of a stable Eu chelate is reacted with the primary amino groups. The labeling technology enables the coupling of a high number of Eu chelates to a single probe. The melting temperatures and hybridization efficiencies of the oligonucleotides are not significantly altered by the labeling process. However, hybridization kinetics of the oligonucleotides are affected by the introduction of multiple modified deoxycytidine residues. In a solid-phase hybridization assay up to 10(7) target molecules can be detected.

Dual-color detection of DNA sequence variants by ligase-mediated analysis

Genetic screening for sequence variants associated with disease is assuming increasing importance in clinical medicine as well as in research. We describe an efficient method for such analyses, comprising a combination of practical features: (1) Amplified DNA samples are analyzed for their ability to serve as templates in standardized allele-specific ligation reactions between oligonucleotide probes; (2) Two allele-specific probes, differentially labeled with either of two lanthanide labels, compete for ligation to a third oligonucleotide (the signal from the two labeled probes can thus be directly compared in a sensitive time-resolved fluorescence detection reaction); and (3) Large sets of analyses are processed in parallel using a 96-pin capture manifold, serving to reduce pipetting steps and the risk of contamination. We present here the basis of the technique and its application to the screening for two common mutations causing cystic fibrosis and alpha 1-antiytrypsin deficiency.

A high-capacity manifold support for the detection of specific IgE antibodies in allergic individuals

A high-capacity manifold support with immobilized antigen was developed for the analysis of IgE-mediated immune reactivity in allergic subjects. Using this 96-pronged support, specific antibodies were trapped and detected from large sets of serum samples. We describe the binding of large amounts of antigen onto the expanded surface of the manifold support, permitting efficient identification of allergic individuals.

A manifold support for molecular genetic reactions

Large numbers of samples can be efficiently processed through sequential reaction steps using a 96-pronged support that projects into individual microtiter wells. The support was constructed by creating a porous surface on a disposable polystyrene manifold, with avidin coupled to this greatly expanded surface. The shape and high binding capacity of the device allow the parallel transfer of large sets of reaction intermediates between different binding or enzymatic processing steps. We have applied the support to increase the efficiency of preparative and analytical molecular genetic reactions. The support also reduce the risks of sample mix-up and contamination in applications such as PCR and DNA sequencing.

Detection of human immunodeficiency virus type 1 by using the polymerase chain reaction and a time-resolved fluorescence-based hybridization assay

The polymerase chain reaction (PCR) has many potential applications in the field of nucleic acid diagnostics. In particular, it has been successfully applied to the detection of pathogens present in low copy numbers such as the human immunodeficiency virus type 1. Here we describe a time-resolved fluorescence-based hybridization assay which, combined with the PCR, offers an extremely sensitive method for the detection of nucleic acids. In this assay format, the PCR is run by standard procedures and the subsequent hybridization reaction is carried out in solution by using two oligonucleotide probes, one biotinylated and one labeled with europium (Eu3+). The sandwich hybrids are then collected onto a streptavidin-coated microtitration well, and the bound Eu3+ is measured in a time-resolved fluorometer. This assay is rapid, user friendly, and quantitative and lends itself to automation. The application of this assay to the detection of human immunodeficiency virus type 1 is described.

The use of europium (Eu3+) labelled primers in PCR amplification of specific target DNA

The polymerase chain reaction (PCR) has many potential applications in the field of DNA probe diagnostics. Here we describe a method that utilizes PCR and time-resolved fluorometry (TRF) for the detection of specific target DNA. First the DNA segment to be detected is amplified according to standard procedures. Then a pair of europium (Eu3+) and biotin-labelled primers nested within the amplified fragment is incorporated in a few additional PCR cycles. Thus amplified DNA fragments are generated that contain an affinity label (biotin) and a detectable label (europium). The doubly-labelled amplified DNA fragments are collected onto streptavidin coated microtitration strips and the bound Eu3+ is measured in a time-resolved fluorometer. We show here the application of this method to the detection of HIV-1 DNA. As few as five copies of HIV-1 DNA could readily be detected using this assay. The method described here is sensitive, rapid and easy to employ. In addition it lends itself to automation.

Preparation of europium-labelled DNA probes and their properties

A chemical method for labelling DNA with a europium chelate is presented. First, primary aliphatic amino groups are introduced onto DNA in a transamination reaction. The transamination reaction is altered by adjusting temperature and duration of the reaction. Subsequently, the modified DNA is reacted with an isothiocyanate derivative of a Eu chelate. The optimum amount of Eu chelates on a DNA probe is 4-8% of total nucleotides. There is a decrease of 0.7 degrees C in the melting temperature of DNA for each incorporated Eu chelate on 100 bases. Hybridization efficiency is lowered by the introduction of Eu chelates but this effect can be partly overcome by using high DNA probe concentrations. The detection limit of the Eu-labelled probe is 0.15 attomoles of target DNA in a mixed-phase hybridization assay on microtitration wells. In addition to high sensitivity the Eu-labelled probes offer convenience in use and results which are quantitative and easy to interpret.

The Ciba Corning ACS:180 benchtop immunoassay analyzer

We describe a new clinical laboratory instrument, the ACS:180, used to automate heterogeneous immunoassay testing. The ACS:180 automates immunoassays in which paramagnetic particles are the solid phase and changes in chemiluminescence are measured. The system can accommodate both competitive and sandwich-type assay configurations. The microprocessor-based instrument fully automates each step of the assay, including sample and reagent addition, separation and wash of paramagnetic particles, and generation and acquisition of the chemiluminescent signal. The instrument has the flexibility to operate in random-access or batch mode. The time from application of sample to first result is less than 15 min; throughput is as much as 180 tests per hour.

The Ciba Corning ACS:180 benchtop immunoassay analyzer

We describe a new clinical laboratory instrument, the ACS:180, used to automate heterogeneous immunoassay testing. The ACS:180 automates immunoassays in which paramagnetic particles are the solid phase and changes in chemiluminescence are measured. The system can accommodate both competitive and sandwich-type assay configurations. The microprocessor-based instrument fully automates each step of the assay, including sample and reagent addition, separation and wash of paramagnetic particles, and generation and acquisition of the chemiluminescent signal. The instrument has the flexibility to operate in random-access or batch mode. The time from application of sample to first result is less than 15 min; throughput is as much as 180 tests per hour.