Impaired communication ability in SOX11 syndrome

BACKGROUND

Speech and language skills are important for social interaction and learning. This study characterised the communication abilities of verbal individuals with SOX11 syndrome using a standardised parent/carer questionnaire, the Children's Communication Checklist (CCC-2).

METHOD

Thirteen parent/carers of verbal individuals (aged 5-19 years) diagnosed with SOX11 syndrome completed the CCC-2. In order to contextualise findings, responses were compared to norms and to data from Noonan syndrome, a relatively well-known genetic diagnosis associated with communication impairment.

RESULTS

For all individuals, the CCC-2 composite score indicated significant communication difficulties. Language structure (speech, syntax, semantics and coherence), pragmatic language (inappropriate initiation, stereotyped language use of context and non-verbal communication) and autistic features (social relations and interests) scores were lower than typically developing norms. Subscale comparisons revealed relative difference in use of context compared to other pragmatic domains (stereotyped language and inappropriate initiation). Individual scores showed substantial variation, particularly in regard to language structure profile. Differences were more pronounced than for Noonan syndrome, specifically in domains of speech, syntax, non-verbal communication and social relations.

CONCLUSIONS

SOX11 syndrome is associated with communication impairment. It is important to assess communication abilities as part of the management of individuals with SOX11 syndrome and understand individual strengths and difficulties in order to provide targeted support.

Clinical application of usage-based phonology: Treatment of cleft palate speech using usage-based electropalotography

PURPOSE

To investigate whether a novel electropalatography (EPG) therapy, underpinned by usage-based phonology theory, can improve the accuracy of target speech sounds for school-aged children and adults with persistent speech sound disorder (SSD) secondary to cleft palate +/- lip.

METHOD

Six consecutively treated participants (7-27 years) with long-standing speech disorders associated with cleft palate enrolled in a multiple baseline (ABA) within-participant case series. The usage-based EPG therapy technique involved high-volume production of words. Speech was assessed on three baselines prior to therapy, during weekly therapy, at completion of therapy, and 3 months post-therapy. Percent correct of target phonemes in untreated words and continuously connected speech were assessed through acoustic phonetic transcription. Intra- and inter-transcriber agreement was determined.

RESULT

Large to medium treatment effect sizes were shown for all participants following therapy (15-33 sessions). Percentage of targets correct for untreated words improved from near 0% pre-therapy, to near 100% for most target sounds post-therapy. Generalisation of target sounds to spontaneous connected speech occurred for all participants and ranged from 78.95-100% (M = 90.66; SD = 10.14) 3 months post-therapy.

CONCLUSION

Clinically significant speech change occurred for all participants following therapy. Response to the novel therapeutic technique is encouraging and further research is indicated.

Editorial Perspective: Maximising the benefits of intervention research for children and young people with developmental language disorder (DLD) - a call for international consensus on standards of reporting in intervention studies for children with and at risk for DLD

Current methods for reporting interventions do not allow key questions of importance to practitioners, service providers, policy-makers and people with DLD to be answered, and hence limit the implementation of effective interventions in the real world. To extend the existing EQUATOR guidelines to the context of speech language therapy/pathology for children with language disorder and to provide more specific guidance on participants, interventions and outcomes within the CONSORT checklist (used to improve the reporting of randomised controlled trials) and TIDieR (Template for Intervention Description and Replication) to ensure consistency of reporting. We will develop a core team to include representatives from each of the key groups who will either use or be influenced by the final reporting guidance across different countries. To achieve each set of aims, we will conduct reviews of the literature (which present typologies of intervention characteristics in (D)LD and related disorders); carry out focus groups; and use systematic consensus methods such as the Delphi technique, nominal group technique or consensus development conferences. Through the development and adoption of standard intervention reporting criteria, we anticipate that we will overcome the numerous barriers for practitioners, services and policy-makers in applying intervention evidence to practice. We believe that establishing international consensus on reporting guidelines would significantly accelerate progress in DLD research and the ease with which it can be used in clinical practice, by capitalising on the growth in intervention studies to enable international collaboration and new methodologies of data pooling, meta-analyses and cross-study comparisons.

Phonological variations in typically-developing Italian-speaking children aged 3;0-4;11

Normative data on phonological acquisition of a language are a prerequisite for evaluating children's speech sound competences. To date, these data are not sufficiently available for Italian. This study, therefore, aimed to describe the phonological development of 183 typically developing monolingual Italian-speaking children aged 3;0-4;11 (four 6-months age bands). Participants were assessed through a picture naming task, and performances analysed in terms of number of phonological variations (Tokens), Types and percentage of occurrence of patterns, and number of infrequent variants (InfrVar) as a measure of stability in speech production. Two cut-off criteria to distinguish InfrVar from phonological patterns were applied. Results showed a gradual reduction of all measures with increasing age. Twenty-two patterns generally in line with previous Italian and cross-linguistic studies were observed, with only five patterns and two phonetic distortions occurring across all age groups. Eight patterns only emerged when applying the lower cut-off criterion, while further seven patterns only occurred with very low frequency or in isolated age groups. These findings highlight the influence of the selected cut-off criterion on the identification of patterns and raise the question of whether some patterns should rather be considered InfVar. Data on younger children are still needed to clarify whether low-frequency patterns are patterns of younger typically developing children that have almost resolved in the age groups assessed. At least half of the phonological variation Tokens fell into the category of InfrVar, indicating a need to pay more attention to this so far ignored measure.

Observations on early fungal infections with relevance for replant disease in fine roots of the rose rootstock Rosa corymbifera 'Laxa'

Replant disease is a worldwide phenomenon affecting various woody plant genera and species, especially within the Rosaceae. Compared to decades of intensive studies regarding replant disease of apple (ARD), the replant disease of roses (RRD) has hardly been investigated. The etiology of RRD is also still unclear and a remedy desperately needed. In greenhouse pot trials with seedlings of the RRD-sensitive rootstock Rosa corymbifera ‘Laxa’ cultured in replant disease affected soils from two different locations, early RRD symptom development was studied in fine roots. In microscopic analyses we found similarities to ARD symptoms with regards to structural damages, impairment in the root hair status, and necroses and blackening in the cortex tissue. Examinations of both whole mounts and thin sections of fine root segments revealed frequent conspicuous fungal infections in association with the cellular disorders. Particularly striking were fungal intracellular structures with pathogenic characteristics that are described for the first time. Isolated fungi from these tissue areas were identified by means of ITS primers, and many of them were members of the Nectriaceae. In a next step, 35 of these isolates were subjected to a multi-locus sequence analysis and the results revealed that several genera and species were involved in the development of RRD within a single rose plant. Inoculations with selected single isolates (Rugonectria rugulosa and Ilyonectria robusta) in a Perlite assay confirmed their pathogenic relationship to early necrotic host plant reactions, and symptoms were similar to those exhibited in ARD.

Effects of an Early Literacy Intervention for Linguistically Diverse Children: A Quasi-Experimental Study

Phonological awareness and letter-sound knowledge underpin children’s early literacy acquisition. Promoting these foundational skills in kindergarten should therefore lead to a better response to formal literacy instruction once started. The present study evaluated a 12-week early literacy intervention for linguistically diverse children who are learning to read in German. The study was set in Luxembourg where kindergarten education is in Luxembourgish and children learn to read in German in Grade 1 of primary school. One hundred and eighty-nine children (mean age = 5;8 years) were assigned to an early literacy intervention in Luxembourgish or to a business as usual control group. Trained teachers delivered the intervention to entire classes, four times a week, during the last year of kindergarten. The early literacy program included direct instruction in phonological awareness and letter-knowledge, while promoting print and book awareness and literacy engagement. Children were assessed pre-intervention, immediately post-intervention and at a 9 months delayed follow-up using measures in Luxembourgish and in German. At the end of the intervention, children in the intervention group performed significantly better than the control group on phonological awareness and letter-knowledge measures in Luxembourgish and the gains in phonological awareness were maintained at 9 months follow-up. The effects generalized to measures of phonological awareness, word-level reading comprehension and spelling in German (effect sizes d > 0.25), but not to German single word/pseudoword reading, at delayed follow-up. Intervention programs designed to support foundational literacy skills can be successfully implemented by regular teachers in a play-based kindergarten context. The findings suggest that early literacy intervention before school entry can produce educationally meaningful effects in linguistically diverse learners.

The efficacy of early language intervention in mainstream school settings: a randomized controlled trial

BACKGROUND

Oral language skills are a critical foundation for literacy and more generally for educational success. The current study shows that oral language skills can be improved by providing suitable additional help to children with language difficulties in the early stages of formal education.

METHODS

We conducted a randomized controlled trial with 394 children in England, comparing a 30-week oral language intervention programme starting in nursery (N = 132) with a 20-week version of the same programme starting in Reception (N = 133). The intervention groups were compared to an untreated waiting control group (N = 129). The programmes were delivered by trained teaching assistants (TAs) working in the children's schools/nurseries. All testers were blind to group allocation.

RESULTS

Both the 20- and 30-week programmes produced improvements on primary outcome measures of oral language skill compared to the untreated control group. Effect sizes were small to moderate (20-week programme: d = .21; 30-week programme: d = .30) immediately following the intervention and were maintained at follow-up 6 months later. The difference in improvement between the 20-week and 30-week programmes was not statistically significant. Neither programme produced statistically significant improvements in children's early word reading or reading comprehension skills (secondary outcome measures).

CONCLUSIONS

This study provides further evidence that oral language interventions can be delivered successfully by trained TAs to children with oral language difficulties in nursery and Reception classes. The methods evaluated have potentially important policy implications for early education.

Early literacy and comprehension skills in children learning English as an additional language and monolingual children with language weaknesses

Many children learning English as an additional language (EAL) show reading comprehension difficulties despite adequate decoding. However, the relationship between early language and reading comprehension in this group is not fully understood. The language and literacy skills of 80 children learning English from diverse language backgrounds and 80 monolingual English-speaking peers with language weaknesses were assessed at school entry (mean age = 4 years, 7 months) and after 2 years of schooling in the UK (mean age = 6 years, 3 months). The EAL group showed weaker language skills and stronger word reading than the monolingual group but no difference in reading comprehension. Individual differences in reading comprehension were predicted by variations in decoding and language comprehension in both groups to a similar degree.

Oral language skills intervention in pre-school-a cautionary tale

BACKGROUND

While practitioners are increasingly asked to be mindful of the evidence base of intervention programmes, evidence from rigorous trials for the effectiveness of interventions that promote oral language abilities in the early years is sparse.

AIMS

To evaluate the effectiveness of a language intervention programme for children identified as having poor oral language skills in preschool classes.

METHODS & PROCEDURES

A randomized controlled trial was carried out in 13 UK nursery schools. In each nursery, eight children (N = 104, mean age = 3 years 11 months) with the poorest performance on standardized language measures were selected to take part. All but one child were randomly allocated to either an intervention (N = 52) or a waiting control group (N = 51). The intervention group received a 15-week oral language programme in addition to their standard nursery curriculum. The programme was delivered by trained teaching assistants and aimed to foster vocabulary knowledge, narrative and listening skills.

OUTCOMES & RESULTS

Initial results revealed significant differences between the intervention and control group on measures of taught vocabulary. No group differences were found on any standardized language measure; however, there were gains of moderate effect size in listening comprehension.

CONCLUSIONS & IMPLICATIONS

The study suggests that an intervention, of moderate duration and intensity, for small groups of preschool children successfully builds vocabulary knowledge, but does not generalize to non-taught areas of language. The findings strike a note of caution about implementing language interventions of moderate duration in preschool settings. The findings also highlight the importance of including a control group in intervention studies.

A Prototype Body-Mounted MRI-Compatible Robot for Needle Guidance in Shoulder Arthrography

A novel compact and lightweight patient-mounted MRI-compatible robot has been designed for MRI image-guided interventions. This robot is intended to enable MRI-guided needle placement as done in shoulder arthrography. The robot could make needle placement more accurate and simplify the current workflow by converting the traditional two-stage arthrography procedure (fluoroscopy-guided needle insertion followed by a diagnostic MRI scan) to a one-stage procedure (streamlined workflow all in MRI suite). The robot has 4 degrees of freedom (DOF), two for orientation of the needle and two for needle positioning. The mechanical design was based on several criteria including rigidity, MRI compatibility, compact design, sterilizability, and adjustability. The proposed workflow is discussed and initial MRI compatibility experiments are presented. The results show that artifacts in the region of interest are minimal and that MRI images of the shoulder were not adversely affected by placing the robot on a human volunteer.

Mechanical activation of pharmaceutical systems

Mechanical activation has become a phenomenon of general significance in pharmaceutics. This report describes the extent of activation induced by relevant processes. With the use of the Eyring equation the transformation of structurally stored energy into chemical energy and the implied free enthalpy as well as the excess free enthalpy (activity) were evaluated from the rate of an indicator reaction. A comparison was made between different kinds of milling and tabletting with respect to pharmaceutical conditions. An optimization of these processes was derived.

Efficacy of language intervention in the early years

BACKGROUND

Oral language skills in the preschool and early school years are critical to educational success and provide the foundations for the later development of reading comprehension.

METHODS

In a randomized controlled trial, 180 children from 15 UK nursery schools (n = 12 from each setting; M(age) = 4;0) were randomly allocated to receive a 30-week oral language intervention or to a waiting control group. Children in the intervention group received 30 weeks of oral language intervention, beginning in nursery (preschool), in three group sessions per week, continuing with daily sessions on transition to Reception class (pre-Year 1). The intervention was delivered by nursery staff and teaching assistants trained and supported by the research team. Following screening, children were assessed preintervention, following completion of the intervention and after a 6-month delay.

RESULTS

Children in the intervention group showed significantly better performance on measures of oral language and spoken narrative skills than children in the waiting control group immediately after the 30 week intervention and after a 6 month delay. Gains in word-level literacy skills were weaker, though clear improvements were observed on measures of phonological awareness. Importantly, improvements in oral language skills generalized to a standardized measure of reading comprehension at maintenance test.

CONCLUSIONS

Early intervention for children with oral language difficulties is effective and can successfully support the skills, which underpin reading comprehension.

Resistively detected nuclear magnetic resonance in n- and p-type GaAs quantum point contacts

We present resistively detected NMR measurements in induced and modulation-doped electron quantum point contacts, as well as induced hole quantum point contacts. While the magnitude of the resistance change and associated NMR peaks in n-type devices is in line with other recent measurements using this technique, the effect in p-type devices is too small to measure. This suggests that the hyperfine coupling between holes and nuclei in this type of device is much smaller than the electron hyperfine coupling, which could have implications in quantum information processing.

A real-time PCR assay for the differentiation of Candida species

AIMS

We established a real-time PCR assay for the detection and strain identification of Candida species and demonstrated the ability to differentiate between Candida albicans the most common species, and also Candida parapsilosis, Candida glabrata, Candida tropicalis and Candida dubliniensis by LightCycler PCR and melting curve analysis.

METHODS AND RESULTS

The DNA isolation from cultures and serum was established using the QIAmp Tissue Kit. The sensitivity of the assay was ≥ 2 genome equivalents/assay. It was possible to differentiate all investigated Candida species by melting curve analysis, and no cross-reaction to human DNA or Aspergillus species could be observed.

CONCLUSIONS

The established real-time PCR assay is a useful tool for the rapid identification of Candida species and a base technology for more complex PCR assays.

SIGNIFICANCE AND IMPACT OF THE STUDY

We carried out initial steps in validation of a PCR assay for the detection and differentiation of medically relevant Candida species. The PCR was improved by generating PCR standards, additional generation of melting curves for species identification and the possibility to investigate different specimens simultaneously.

Development of a test battery for assessing phonological awareness in German-speaking children

The development of phonological awareness (PA), the ability to reflect on the sound structure of words independent of their meaning, has been extensively explored in English-speaking children. However, this is not the case for other languages. The aim of this study was to develop a comprehensive PA test battery for German-speaking preschool children, considering psycholinguistic, linguistic, and cognitive aspects and to carry out analyses of its psychometric properties. Cross-sectional data from a sample of 55 children (CA 4;0-6;11 years) were collected. Preliminary findings confirm validity and reliability of the test battery, and support previous findings that PA develops from larger to smaller linguistic units. Phoneme-level tasks were consistently associated with letter knowledge. The new instrument is a promising tool for basic research (e.g. cross-linguistic comparisons of PA development) as well as for clinical and educational practice (e.g. planning speech and language therapy or literacy-oriented intervention).

Enhanced perceived responsibility decreases metamemory but not memory accuracy in obsessive–compulsive disorder (OCD)

Mixed findings have been obtained in prior research with respect to the presence and severity of memory and metamemory deficits in obsessive-compulsive disorder (OCD). We tested the hypothesis that experimentally induced increments of subjective responsibility would lead to a disproportionately strong decline of memory confidence and enhanced response latencies in OCD while leaving memory accuracy unaffected. Twenty-eight OCD patients and 28 healthy controls were presented a computerized memory test framed with two different scenarios. In the neutral scenario, the participant was requested to imagine purchasing 15 items from a do-it-yourself store. In the recognition phase, the 15 needed items were presented along with 15 distractor items. The participant was asked to decide whether items were on his or her shopping list or not, graded by subjective confidence. In the responsibility scenario, the general experimental setup was analogous except that the participant now had to envision that he or she was a helper in a region recently struck by an earthquake, dispatched to provide 15 urgently needed goods from a nearby town. In line with prior work by our group, samples did not differ in either condition on memory accuracy in a subsequent recognition task. As hypothesized, OCD participants were less certain in their responses for the high responsibility condition than controls. Whereas patients and controls did not differ in their subjective estimates for memorized items, patients expressed stronger doubt that their earthquake mission was successful. The findings indicate that low memory confidence in OCD may only be elicited in situations where perceived responsibility is high and that patients may share higher performance standards ("good is not good enough") than controls when perceived responsibility is inflated.

Symptom dimensions in obsessive-compulsive disorder: prediction of cognitive-behavior therapy outcome

OBJECTIVE

A significant number of patients with obsessive-compulsive disorder (OCD) fail to benefit sufficiently from treatments. This study aimed to evaluate whether certain OCD symptom dimensions were associated with cognitive-behavioral therapy (CBT) outcome.

METHOD

Symptoms of 104 CBT-treated in-patients with OCD were assessed with the clinician-rated Yale-Brown Obsessive-Compulsive Scale symptom checklist. Logistic regression analyses examined outcome predictors.

RESULTS

The most frequent OCD symptoms were aggressive and contamination obsessions, and compulsive checking and cleaning. Patients with hoarding symptoms at baseline (n = 19) were significantly less likely to become treatment responders as compared to patients without these symptoms. Patients with sexual and religious obsessions tended to respond less frequently, although this failed to reach statistical significance (P = 0.07). Regression analyses revealed that higher scores on the hoarding dimension were predictive of non-response, even after controlling for possible confounding variables.

CONCLUSION

Our results strongly indicate that in-patients with obsessive-compulsive hoarding respond poorly to CBT.

Impact of comorbid depressive symptoms on neuropsychological performance in obsessive-compulsive disorder

There is indirect evidence from previous research that several executive disturbances in obsessive-compulsive disorder (OCD) are mediated by comorbid depressive symptoms. For the present study, the authors investigated whether OCD patients with elevated Hamilton Rating Scale for Depression (HRSD) scores would exhibit deficits in tasks sensitive to the medial and dorsolateral frontal cortex as well as other executive tasks. The 36 OCD patients were split along the median according to their HRSD scores and compared with matched control subjects. Patients with high HRSD scores performed significantly worse than control subjects and patients with low HRSD scores on the Wisconsin Card Sorting Test, the Trail-Making Test (TMT, Part B), and the TMT difference score. Moreover, patients with high HRSD scores exhibited deficits on a (creative) verbal fluency task. It is suggested that comorbid depressive symptoms may have artificially inflated some executive deficit scores in previous studies.

Impact of comorbid depressive symptoms on neuropsychological performance in obsessive-compulsive disorder

There is indirect evidence from previous research that several executive disturbances in obsessive-compulsive disorder (OCD) are mediated by comorbid depressive symptoms. For the present study, the authors investigated whether OCD patients with elevated Hamilton Rating Scale for Depression (HRSD) scores would exhibit deficits in tasks sensitive to the medial and dorsolateral frontal cortex as well as other executive tasks. The 36 OCD patients were split along the median according to their HRSD scores and compared with matched control subjects. Patients with high HRSD scores performed significantly worse than control subjects and patients with low HRSD scores on the Wisconsin Card Sorting Test, the Trail-Making Test (TMT, Part B), and the TMT difference score. Moreover, patients with high HRSD scores exhibited deficits on a (creative) verbal fluency task. It is suggested that comorbid depressive symptoms may have artificially inflated some executive deficit scores in previous studies.

Attempted and completed suicide in older subjects: results from the WHO/EURO Multicentre Study of Suicidal Behaviour

OBJECTIVE

The authors present an analysis of findings for the 65 years and over age group from the WHO/EURO Multicentre Study of Suicidal Behaviour (1989-93).

METHODS

Multinational data on non-fatal suicidal behaviour is derived from 1518 subjects in 16 European centres. Local district data on suicide were available from 10 of the collaborating centres.

RESULTS

Stockholm (Sweden), Pontoise (France) and Oxford (UK) had the highest suicide attempts rates. In most centres, the majority of elderly who attempted suicide were widow(er)s, often living alone, who used predominantly voluntary drug ingestion. Non-fatal suicidal behaviour decreased with increasing age, whereas suicide rates rose. The ratio between fatal and non-fatal behaviours was 1:2, that for males/females almost 1:1. In the years considered, substantial stability in suicide and attempted suicide rates was observed. As their age increased, suicidal subjects displayed only a limited tendency to repeat self-destructive acts. Moreover, there was little correlation between attempted suicide and suicide rates, which carries different clinical implications for non-fatal suicidal behaviour in the elderly compared with younger subjects in the same WHO/EURO study.

Expression of soluble, recombinant alphavbeta3 integrin fragments in Escherichia coli

No prokaryotic expression of integrin alphavbeta3 has been reported so far. We report here the expression of C-terminally truncated alphavbeta3 receptors in E. coli considering the known features required for dimerization and ligand binding. The expressed protein was insoluble despite of the addition of 'solubilizers' to the culture medium. Osmotic stress conditions combined with added exogenous solutes resulted in a small part of soluble receptor. The alphavbeta3 variants were purified from inclusion bodies or from soluble cytoplasmic maltose binding protein fusions. Heterodimerization of the subunits was proved by immunoprecipitation assays. Receptor-ligand binding was found to depend on the concentration. A competition assay with RGD peptides referred to unspecific receptor-ligand interaction. The latter fact was consistent with the finding that soluble receptors did not bind on RGD peptide-coupled sepharose (GRGDSPK sepharose).

Suicide among German federal and state police officers

Most American studies report higher police officer suicide rates in comparison to age-matched populations. In the Federal Republic of Germany police organizations are comprised of Federal Customs, 16 state police, and 2 federal police organizations. A survey carried out in 1997 yielded higher suicide rates for police officers also in Germany in comparison to rates of the comparable age group (25 per 100,000 vs 20 per 100,000). The most commonly used suicide method was firearms (66-71%). Hypotheses often attribute this high suicidality among police officers to higher work stress than in other professions. Other hypotheses implicate individual variables such as psychiatric illnesses, alcoholism, and interpersonal and marital problems. A transactional model might explain these different views.

Attempted suicide in Europe: rates, trends and sociodemographic characteristics of suicide attempters during the period 1989-1992. Results of the WHO/EURO Multicentre Study on Parasuicide

The World Health Organization/EURO Multicentre Project on Parasuicide is part of the action to implement target 12 of the WHO programme, "Health for All by the Year 2000', for the European region. Sixteen centres in 13 European countries are participating in the monitoring aspect of the project, in which trends in the epidemiology of suicide attempts are assessed. The highest average male age-standardized rate of suicide attempts was found for Helsinki, Finland (314/100,000), and the lowest rate (45/100,000) was for Guipuzcoa, Spain, representing a sevenfold difference. The highest average female age-standardized rate was found for Cergy-Pontoise, France (462/100,000), and the lowest (69/100,000) again for Guipuzcoa, Spain. With only one exception (Helsinki), the person-based suicide attempt rates were higher among women than among men. In the majority of centres, the highest person-based rates were found in the younger age groups. The rates among people aged 55 years or over were generally the lowest. For the majority of the centres, the rates for individuals aged 15 years or over decreased between 1989 and 1992. The methods used were primarily "soft' (poisoning) or cutting. More than 50% of the suicide attempters made more than one attempt, and nearly 20% of the second attempts were made within 12 months after the first attempt. Compared with the general population, suicide attempters more often belong to the social categories associated with social destabilization and poverty.

A prospective study of haemostatic parameters in relation to the clinical course of myeloproliferative disorders

Platelet function and the clinical course of the disease were prospectively investigated in 29 patients with myeloproliferative disorders. Serial determinations (median: 5 investigations per patient within 17 months) of platelet aggregation, plasma and intraplatelet concentrations of beta-thromboglobulin (beta TG) and platelet factor 4 (PF4), and of fibrinopeptide A (FPA) plasma levels were carried out. In the chronic phase of polycythaemia vera, patients with thrombohaemorrhagic complications during the study period had higher platelet count, more severe platelet aggregation defects, and increased plasma levels of beta TG and FPA compared to patients without complications. However, thrombohaemorrhagic complications were not predicted by changes in these parameters in the individual patient during the chronic disease phase. When patients with chronic myelogenous leukaemia entered blast crisis, bleeding complications were related to thrombocytopenia, impaired platelet function and low intraplatelet concentrations of beta TG and PF4. Cytoreduction by chemotherapy in the chronic phase of CML did not alter beta TG and PF4 plasma levels, whereas treatment of polycythaemia rubra vera by venesection favourably influenced platelet alpha-granule secretion and increased intraplatelet concentrations of beta TG and PF4.

Bleeding and thrombosis in chronic myeloproliferative disorders: relation of platelet disorders to clinical aspects of the disease

Bleeding and thrombosis are a major cause of morbidity and mortality in myeloproliferative disorders (MPD). This study evaluates the relation between thrombohemorrhagic complications and platelet abnormalities in different subgroups of MPD. In 57 MPD patients thrombohemorrhagic complications occurred in 71% of patients with polycythemia rubra vera and 50% of patients with osteomyelofibrosis and primary thrombocythemia but in only 29% of patients with chronic myelogenous leukemia. Increased beta-thromboglobulin and platelet factor 4 plasma levels, platelet aggregation defects, and increased dispersion of the platelet volume distribution curve were most frequent in those subgroups where most serious thrombohemorrhagic complications were observed, and multiple platelet-related abnormalities were often found simultaneously. Fibrinopeptide A plasma levels were rarely elevated, however. Our results indicate that platelet abnormalities associated with bleeding and thrombosis are primarily determined by the clinical subgroup of myeloproliferative disease.

Experimental confirmation of the change of water structure in the critical range of micelle formation: a new method of critical micelle concentration (CMC) determination

The decrease in the water structure in the critical range of micelle formation, which had been deduced theoretically, was confirmed by means of a new determination method. The method was based upon the dependence of the gelatin helicity on the water structure and the correlation between the helix-coil equilibrium and the disintegration of gelatin microcapsules. The significant rise in the disintegration rate, indicating a decay of water structure, represents also a new method of critical micelle concentration (CMC) determination.