X-ray 3D imaging-based microunderstanding of granular mixtures: Stiffness enhancement by adding small fractions of soft particles

This research focuses on performing ultrasound propagation measurements and micro-X-ray computed tomography (µXRCT) imaging on prestressed granular packings prepared with biphasic mixtures of monodisperse glass and rubber particles at different compositions/fractions. Ultrasound experiments employing piezoelectric transducers, mounted in an oedometric cell (complementing earlier triaxial cell experiments), are used to excite and detect longitudinal ultrasound waves through randomly prepared mixtures of monodisperse stiff/soft particles. While the fraction of the soft particles is increasing linearly from zero, the effective macroscopic stiffness of the granular packings transits nonlinearly and nonmonotonically toward the soft limit, remarkably via an interesting stiffer regime for small rubber fractions between 0.1 ≲ ν ≲ 0.2. The contact network of dense packings, as accessed from µXRCT, plays a key role in understanding this phenomenon, considering the structure of the network, the chain length, the grain contacts, and the particle coordination. While the maximum stiffness is due to surprisingly shortened chains, the sudden drop in elastic stiffness of the mixture packings, at ν ≈ 0.4, is associated with chains of particles that include both glass and rubber particles (soft chains); for ν ≲ 0.3, the dominant chains include only glass particles (hard chains). At the drop, ν ≈ 0.4, the coordination number of glass and rubber networks is approximately four and three, respectively, i.e., neither of the networks are jammed, and the chains need to include particles from another species to propagate information.

[Degenerative cervical spine diseases: fusion vs. total disc replacement : What can be done when?]

Motion preserving surgery within the cervical spine may be performed by special implants, for example, c spine disc prosthesis or total disc replacement (cTDR), or by simple decompression of the cervical nerve roots. However, also fusion surgery may be performed with good results. Here, we summarize indications as well as contraindications for motion preserving techniques and indications for fusion surgery. cTDR is indicated in special cases of soft disc herniation, especially in younger individuals without signs of myelopathy. Posterior decompression may be used as an alternative, especially if anterior surgery is not possible. If degeneration is severe, in the presence of kyphosis, severe canal encroachment, instability, and in cases of myelopathy, cervical spine fusion seems to be the better way.

The Influence of Micronutrients on Cognitive Function and Performance

There has been much media speculation (often sensationalist and conflicting) regarding the potential influence of micronutrients on cognitive function and performance. Our aim was to identify the micronutrients specifically implicated in cognitive function and to review the literature to identify original sources underlying the media coverage. Literature searches were carried out to identify recent clinical trials, reviews, editorials and meetings describing the biochemical and physiological role of individual micronutrients. No attempt was made to grade the evidence. The searches confirmed that the water-soluble vitamins (B group and C), together with the minerals, calcium, magnesium and zinc, are most relevant to cognitive performance. Clinical evidence revealed that marginal deficiencies of one or more of these micronutrients are not uncommon, even in the developed countries, and that such deficiencies may affect cognitive performance, especially in vulnerable groups such as the elderly and those individuals who are exposed to occupational pressures and a stressful lifestyle.

Treatment of traumatized victims of war and torture: a randomized controlled comparison of narrative exposure therapy and stress inoculation training

BACKGROUND

The aim of the present randomized controlled trial was to compare the outcome of 2 active treatments for posttraumatic stress disorder (PTSD) as a consequence of war and torture: narrative exposure therapy (NET) and stress inoculation training (SIT).

METHODS

Twenty-eight PTSD patients who had experienced war and torture, most of them asylum seekers, received 10 treatment sessions of either NET or SIT at the Outpatient Clinic for Refugees, University of Konstanz, Germany. Posttests were carried out 4 weeks after treatment, and follow-up tests were performed 6 months and 1 year after treatment. The main outcome measure was the PTSD severity score according to the Clinician-Administered PTSD Scale (CAPS) at each time point.

RESULTS

A significant reduction in PTSD severity was found for NET, but not for SIT. A symptom reduction in the NET group occurred between pretest and the 6-month follow-up examination, the effect size being d = 1.42 (for SIT: d = 0.12), and between pretest and the 1-year follow-up, the effect size being d = 1.59 (for SIT: d = 0.19). The rates and scores of major depression and other comorbid disorders did not decrease significantly over time in either of the 2 treatment groups.

CONCLUSIONS

The results indicate that exposure treatments like NET lead to a significant PTSD symptom reduction even in severely traumatized refugees and asylum seekers.

Expression of platelet-bound stromal cell-derived factor-1 in patients with non-valvular atrial fibrillation and ischemic heart disease

AIMS

Blood cell infiltration and inflammation are involved in atrial remodelling during atrial fibrillation (AF) although the exact mechanisms of inflammatory cell recruitment remain poorly understood. Platelet-bound stromal cell-derived factor-1 (SDF-1) is increased in cases of ischemic myocardium and regulates recruitment of CXCR4(+) cells on the vascular wall. Whether platelet-bound SDF-1 expression is differentially influenced by non-valvular paroxysmal or permanent atrial fibrillation (AF) in patients with stable angina pectoris (SAP) or acute coronary syndrome (ACS) has not been reported so far.

METHODS AND RESULTS

A total of 1291 consecutive patients with coronary artery disease (CAD) undergoing coronary angiography were recruited. Among the patients with SAP, platelet-bound-SDF-1 is increased in patients with paroxysmal AF compared with SR or to persistent/permanent AF (P < 0.05 for both). Platelet-bound SDF-1 correlated with plasma SDF-1 (r = 0.488, P = 0.013) in patients with AF and ACS, which was more pronounced among patients with persistent AF (r = 0.842, P = 0.009). Plasma SDF-1 was increased in persistent/permanent AF compared with SR. Patients with ACS presented with enhanced platelet-bound-SDF-1 compared with SAP. Interestingly, among patients with ACS, patients with paroxysmal or persistent/permanent AF presented with an impaired platelet-bound SDF-1 expression compared with patients with SR.

CONCLUSIONS

Differential expression of platelet-bound and plasma SDF-1 was observed in patients with AF compared with SR which may be involved in progenitor cell mobilization and inflammatory cell recruitment in patients with AF and ischemic heart disease. Further in vivo studies are required to elucidate the role of SDF-1 in atrial remodeling and the atrial fibrillation course.

Narrative exposure therapy for PTSD increases top-down processing of aversive stimuli--evidence from a randomized controlled treatment trial

Abstract

Registration of the clinical trial

Number: NCT00563888

Name: "Change of Neural Network Indicators Through Narrative Treatment of PTSD in Torture Victims" ULR: http://www.clinicaltrials.gov/ct2/show/NCT00563888

Childhood adversity, mental ill-health and aggressive behavior in an African orphanage: Changes in response to trauma-focused therapy and the implementation of a new instructional system

BACKGROUND

The number of orphans in Sub-Saharan Africa is constantly rising. While it is known that family or community care is preferable over institutional care of African orphans, little is known about the quality of care in orphanages and possibilities of improvement. STUDY 1:

METHODS

Exposure to traumatic stress, experiences of violence in the home, school and orphanage, as well as mental ill-health and aggression of 38 children (mean age of M = 8.64 years) living in an orphanage in rural Tanzania were assessed at two time points. The severity of post-traumatic stress disorder symptoms (PTSD), depressive symptoms, and internalizing and externalizing problems were used as indicators of mental ill-health.

RESULTS

Violence experienced in the orphanage correlated more strongly with all indicators of mental ill-health than violence in the former home, school or neighborhood at time point 1. Additionally, violence experienced in the orphanage had a positive relationship with the aggressive behavior of the children at time point 2. STUDY 2:

METHODS

With the help of the pre-post assessment of Study 1, the implementation of a new instructional system and psychotherapeutic treatment (KIDNET) for trauma-related illness were evaluated.

RESULTS

In response to both, a change in the instructional system and psychotherapeutic treatment of PTSD, a massive decline in experienced violence and in the severity of PTSD-symptoms was found, whereas depressive symptoms and internalizing and externalizing problems exhibited little change.

CONCLUSIONS

These studies show that violence, especially in the orphanage, can severely contribute to mental ill-health in orphans and that mental health can be improved by implementing a new instructional system and psychotherapeutic treatment in an orphanage. Moreover, the results indicate that the experience of violence in an orphanage also plays a crucial role in aggressive behavior of the orphans.

Transgenerational impact of intimate partner violence on methylation in the promoter of the glucocorticoid receptor

Prenatal exposure to maternal stress can have lifelong implications for psychological function, such as behavioral problems and even the development of mental illness. Previous research suggests that this is due to transgenerational epigenetic programming of genes operating in the hypothalamic-pituitary-adrenal axis, such as the glucocorticoid receptor (GR). However, it is not known whether intrauterine exposure to maternal stress affects the epigenetic state of these genes beyond infancy. Here, we analyze the methylation status of the GR gene in mothers and their children, at 10-19 years after birth. We combine these data with a retrospective evaluation of maternal exposure to intimate partner violence (IPV). Methylation of the mother's GR gene was not affected by IPV. For the first time, we show that methylation status of the GR gene of adolescent children is influenced by their mother's experience of IPV during pregnancy. As these sustained epigenetic modifications are established in utero, we consider this to be a plausible mechanism by which prenatal stress may program adult psychosocial function.

Men who have sex with men: estimating the size of at-risk populations in London primary care trusts

The objective of this study was to estimate local at-risk populations of men who have sex with men (MSM) in London primary care trusts (PCTs) to inform the commissioning of targeted health interventions. Estimated population size and prevalence of diagnosed HIV in MSM in all of London were calculated using data from the British National Survey of Sexual Attitudes and Lifestyles (NATSAL), Greater London Authority population estimates and the annual survey of diagnosed MSM (Survey of Prevalent HIV Infections Diagnosed [SOPHID]). Estimated MSM population sizes at the PCT level were calculated using un-weighted and SOPHID-weighted methods and methods discussed. Four-fifths of MSM with diagnosed HIV infection in Greater London lived in inner London. Estimated population size of MSM 16-44 years in inner London was 66,000; estimated overall prevalence of diagnosed HIV infection among MSM was 9.5%. Our models show substantial variation at the PCT level between the two methods. Using the SOPHID-weighted method MSM account for up to 16% of the male population in some London PCTs, compared with as low as 3% in others. We provide a novel method of estimating at-risk MSM populations living in inner London PCTs indicating that proportions of MSM vary widely between PCTs. Significant proportions of MSM among the resident populations in several PCTs warrant inclusion of MSM health needs in core PCT prevention and service programming. In light of data source limitations further validation studies are needed.

The Tortured Brain

Traumatic stressors such as water boarding, electric shock, or false execution all activate similar bodily, affective, and cognitive responses even when they are quite different from one another. As a result, the memory traces merge into a “trauma network” that includes sensory memories but becomes detached from the particular episodic memory; that is, the trauma network has no time or place. As, with increasing traumatic experiences, more and more cues become integrated in the network, the threshold for excitation is continually lowered and the individual is likely to show frequent alarm and other defense responses to reminders of the trauma. Neuroplastic mechanisms determine subsequent reorganization of brain circuitry in order to adapt to a presumed permanent need for defense.

We hypothesized that aversive pictorial material is differentially processed in visual as well as frontal and limbic areas of the traumatized brain. We used Rapid Serial Visual Presentation (three pictures per second) to present aversive, neutral, and appetitive pictorial stimuli. Event-related magnetic fields were recorded in 41 survivors of torture and organized violence who suffered from posttraumatic stress disorder (PTSD) as well as 43 controls with a comparable ethnic background. Traumatized individuals showed an early shift in the processing of aversive pictures from sensory visual areas to fronto-temporal areas and the amygdala compared to controls without trauma-related symptoms. For survivors, as opposed to controls, these stimuli automatically activate aspects of the defense cascade and thus lead to an excitation of action-related neural activity. We conclude that an enlarged fear network in survivors of organized violence has a low excitation threshold, thus leading to prominent PTSD symptoms. A disintegration of the fear network by reconnecting its elements to the respective episodic memory or by some form of inhibition of the network may bring relief.

Narrative exposure therapy for 7- to 16-year-olds: a randomized controlled trial with traumatized refugee children

The authors examined the effectiveness of narrative exposure therapy for children (KIDNET) in treating posttraumatic stress disorder (PTSD) in refugee children living in exile. Twenty-six children traumatized by organized violence were randomly assigned to KIDNET or to a waiting list. Significant treatment by time interactions on all PTSD-relevant variables indicated that the KIDNET group, but not the controls, showed a clinically significant improvement in symptoms and functioning. Success of the KIDNET group remained stable at 12-month follow-up. This study confirms previous findings that, if left untreated, PTSD in children may persist for an extended period. However, it also shows that it is possible to effectively treat chronic PTSD and restore functioning in traumatized refugee children in only 8 treatment sessions.

Prävalenz von traumatischen Stresserfahrungen und seelischen Erkrankungen bei in Deutschland lebenden Kindern von Asylbewerbern

Zusammenfassung. Theoretischer Hintergrund: Während Untersuchungen in Krisenregionen gezeigt haben, dass Flüchtlingskinder häufig unter psychischen Erkrankungen leiden und behandlungsbedürftig sind, liegen bis zum jetzigen Zeitpunkt noch kaum Kenntnisse über die Situation in Deutschland bei Kindern von Asylbewerbern vor. Fragestellung: Wie hoch ist die Prävalenz von psychischen Erkrankungen und damit der Behandlungsbedarf bei Flüchtlingskindern in Deutschland? Methode: 104 Kinder von Asylbewerbern wurden in staatlichen Gemeinschaftsunterkünften im Rahmen von standardisierten psychodiagnostischen Interviews im Hinblick auf psychische Erkrankungen untersucht. Ergebnisse: 19% der Kinder litten unter einer Posttraumatischen Belastungsstörung, weitere Störungen traten eher selten auf. In psychotherapeutischer Behandlung befanden sich nur 4,8% der Kinder. Schlussfolgerungen: Flüchtlingskinder besitzen ein hohes Risiko für chronische Traumafolgeerkrankungen, wodurch eine normale und gesunde Entwicklung in sozialen, schulischen und beruflichen Bereichen behindert wird. Entsprechende psychotherapeutische Hilfe sollte daher weiter entwickelt und breiter angeboten werden.

Script-driven imagery of self-injurious behavior in patients with borderline personality disorder: a pilot FMRI study

OBJECTIVE

Self-injurious behavior (SIB) is one of the most distinctive features of borderline personality disorder (BPD) and related to impulsivity and emotional dysregulation.

METHOD

Female patients with BPD (n = 11) and healthy controls (n = 10) underwent functional magnetic resonance imaging while listening to a standardized script describing an act of self-injury. Experimental sections of the script were contrasted to the neutral baseline section and group-specific brain activities were compared.

RESULTS

While imagining the reactions to a situation triggering SIB, patients with BPD showed significantly less activation in the orbitofrontal cortex compared with controls. Furthermore, only patients with BPD showed increased activity in the dorsolateral prefrontal cortex during this section and a decrease in the mid-cingulate while imagining the self-injurious act itself.

CONCLUSION

This pattern of activation preliminary suggests an association with diminished emotion regulation, impulse control as well as with response selection and reappraisal during the imagination of SIB.

Treating children traumatized by war and Tsunami: a comparison between exposure therapy and meditation-relaxation in North-East Sri Lanka

BACKGROUND

The North-Eastern part of Sri Lanka had already been affected by civil war when the 2004 Tsunami wave hit the region, leading to high rates of posttraumatic stress disorder (PTSD) in children. In the acute aftermath of the Tsunami we tested the efficacy of two pragmatic short-term interventions when applied by trained local counselors.

METHODS

A randomized treatment comparison was implemented in a refugee camp in a severely affected community. 31 children who presented with a preliminary diagnosis of PTSD were randomly assigned either to six sessions Narrative Exposure Therapy for children (KIDNET) or six sessions of meditation-relaxation (MED-RELAX). Outcome measures included severity of PTSD symptoms, level of functioning and physical health.

RESULTS

In both treatment conditions, PTSD symptoms and impairment in functioning were significantly reduced at one month post-test and remained stable over time. At 6 months follow-up, recovery rates were 81% for the children in the KIDNET group and 71% for those in the MED-RELAX group. There was no significant difference between the two therapy groups in any outcome measure.

CONCLUSION

As recovery rates in the treatment groups exceeded the expected rates of natural recovery, the study provides preliminary evidence for the effectiveness of NET as well as meditation-relaxation techniques when carried out by trained local counselors for the treatment of PTSD in children in the direct aftermath of mass disasters.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier:NCT00820391.

Setting up an enhanced surveillance of newly acquired hepatitis C infection in men who have sex with men: a pilot in London and South East region of England

Preliminary findings suggest ongoing HCV transmission among MSM infected with human immunodeficiency virus (HIV) and that enhanced surveillance for newly acquired HCV in MSM is feasible.

Setting up an enhanced surveillance of newly acquired hepatitis C infection in men who have sex with men: a pilot in London and South East region of England

We describe the implementation of an enhanced surveillance pilot for newly acquired hepatitis C (HCV) in men who have sex with men (MSM) in London and the South East region of England. Preliminary findings suggest ongoing HCV transmission among MSM infected with human immunodeficiency virus (HIV) and that enhanced surveillance for newly acquired HCV in MSM is feasible.

Narrative exposure therapy for the treatment of traumatized children and adolescents (KidNET): from neurocognitive theory to field intervention

Many children in war-affected and refugee populations have experienced multiple traumatic experiences, and high rates of psychologic disorders, especially posttraumatic stress disorder (PTSD), are found. Intervention strategies require pragmatic and effective approaches to treatment. This article describes the rationale for and the use of narrative exposure therapy in children (KidNET). KidNET is a short-term treatment for PTSD based on a neurocognitive theory of traumatic memory. Early treatment trials, including randomized controlled studies, show promising results for the treatment of children and adolescents who have PTSD living in war-affected countries and refugee communities.

Altered oscillatory brain dynamics after repeated traumatic stress

BACKGROUND

Repeated traumatic experiences, e.g. torture and war, lead to functional and structural cerebral changes, which should be detectable in cortical dynamics. Abnormal slow waves produced within circumscribed brain regions during a resting state have been associated with lesioned neural circuitry in neurological disorders and more recently also in mental illness.

METHODS

Using magnetoencephalographic (MEG-based) source imaging, we mapped abnormal distributions of generators of slow waves in 97 survivors of torture and war with posttraumatic stress disorder (PTSD) in comparison to 97 controls.

RESULTS

PTSD patients showed elevated production of focally generated slow waves (1-4 Hz), particularly in left temporal brain regions, with peak activities in the region of the insula. Furthermore, differential slow wave activity in right frontal areas was found in PTSD patients compared to controls.

CONCLUSION

The insula, as a site of multimodal convergence, could play a key role in understanding the pathophysiology of PTSD, possibly accounting for what has been called posttraumatic alexithymia, i.e., reduced ability to identify, express and regulate emotional responses to reminders of traumatic events. Differences in activity in right frontal areas may indicate a dysfunctional PFC, which may lead to diminished extinction of conditioned fear and reduced inhibition of the amygdala.

Increase in diagnosed newly acquired hepatitis C in HIV-positive men who have sex with men across London and Brighton, 2002-2006: is this an outbreak?

OBJECTIVES

To determine the incidence of diagnosed newly acquired hepatitis C virus (HCV) in HIV-positive men who have sex with men (MSM) across London and Brighton in order to inform public health interventions.

METHODS

Cases were defined as MSM attending London and Brighton HIV/genitourinary medicine clinics from January 2002 to June 2006, with HCV PCR RNA or antibody positive, and a negative HCV test in the previous three years. The yearly number of cases and HCV screening policy in MSM were examined. A negative binomial regression model was used to estimate HCV incidence density rate ratio and 95% CI.

RESULTS

20 out of 38 clinics provided information, covering 84% of the HIV-positive MSM workload in London and 100% in Brighton. The estimated overall incidence was 9.05 per 1000 HIV-positive MSM patient-years. It increased from 6.86 per 1000 in 2002 to 11.58 per 1000 during January-June 2006. Incidence at clinics ranged from 0 to 15.4 (median 6.52) per 1000 HIV-positive MSM patient-years. There was some evidence of difference in the incidence and trend (p = 0.02) in each clinic. The average annual rise in incidence of HCV was 20% (95% CI 4% to 39%, p = 0.001). There was little evidence of such transmission among MSM with negative or unknown HIV status.

CONCLUSIONS

HCV incidence clearly increased among HIV-positive MSM in London and Brighton during January 2002 to June 2006. Prospective enhanced surveillance of HCV in MSM, including HIV status and behavioural risk factors, is recommended to help inform control measures and better determine the frequency of transmission in all MSM.

Lack of cortisol response in patients with posttraumatic stress disorder (PTSD) undergoing a diagnostic interview

BACKGROUND

According to DSM-IV, the diagnosis of posttraumatic stress disorder (PTSD) requires the experience of a traumatic event during which the person's response involved intense fear, helplessness, or horror. In order to diagnose PTSD, clinicians must interview the person in depth about his/her previous experiences and determine whether the individual has been traumatized by a specific event or events. However, asking questions about traumatic experiences can be stressful for the traumatized individual and it has been cautioned that subsequent "re-traumatization" could occur. This study investigated the cortisol response in traumatized refugees with PTSD during a detailed and standardized interview about their personal war and torture experiences.

METHODS

Participants were male refugees with severe PTSD who solicited an expert opinion in the Psychological Research Clinic for Refugees of the University of Konstanz. 17 patients were administered the Vivo Checklist of War, Detention, and Torture Events, a standardized interview about traumatic experiences, and 16 subjects were interviewed about absorption behavior. Self-reported measures of affect and arousal, as well as saliva cortisol were collected at four points. Before and after the experimental intervention, subjects performed a Delayed Matching-to-Sample (DMS) task for distraction. They also rated the severity of selected PTSD symptoms, as well as the level of intrusiveness of traumatic memories at that time.

RESULTS

Cortisol excretion diminished in the course of the interview and showed the same pattern for both groups. No specific response was detectable after the supposed stressor. Correspondingly, ratings of subjective well-being, memories of the most traumatic event(s) and PTSD symptoms did not show any significant difference between groups. Those in the presumed stress condition did not perform worse than persons in the control condition after the stressor. However, both groups performed poorly in the DMS task, which is consistent with memory and concentration problems demonstrated in patients with PTSD.

CONCLUSION

A comprehensive diagnostic interview including questions about traumatic events does not trigger an HPA-axis based alarm response or changes in psychological measures, even for persons with severe PTSD, such as survivors of torture. Thus, addressing traumatic experiences within a safe and empathic environment appears to impose no unacceptable additional load to the patient.

The role of vitamins and minerals in energy metabolism and well-being

Physicians are frequently confronted with patients complaining of fatigue, tiredness and low energy levels. In the absence of underlying disease, these symptoms could be caused by a lack of vitamins and minerals. Certain risk groups like the elderly and pregnant women are well-recognized. Our aim was, therefore, to find out if other, less well-established groups might also be at risk. Thus, the objectives of this review are: to describe the inter-relationship between micronutrients, energy metabolism and well-being; identify risk groups for inadequate micronutrient intake; and explore the role of micronutrient supplementation in these groups. A review of the literature identified an important group at risk of inadequate micronutrient intake: young adults, often women, with a demanding lifestyle who are physically active and whose dietary behaviour is characterized by poor choices and/or regular dieting. Micronutrient supplementation can alleviate deficiencies, but supplements must be taken for an adequate period of time.

Decoupling neural networks from reality: dissociative experiences in torture victims are reflected in abnormal brain waves in left frontal cortex

From a neuroscience perspective, little is known about the long-term effect of torture. Dissociative experiences and posttraumatic stress disorder are often the results of this experience. We examined psychological dissociation within a group of 23 torture victims and report its manifestations within neural networks in the human brain. In particular, we observed that dissociative experiences are associated with slow abnormal brain waves generated in left ventrolateral frontal cortex. Given that focal slow waves often result from depriving neural networks of major input, the present results may indicate decoupling of frontal affective processors from left cortical language areas. This interpretation is consistent with the fact that disturbed access to structured verbal memory concerning traumatic events is a core feature of the dissociative experience.

Post-tsunami stress: a study of posttraumatic stress disorder in children living in three severely affected regions in Sri Lanka

At 3 to 4 weeks after the December 2004 tsunami disaster we assessed symptoms of posttraumatic stress disorder (PTSD) in 264 children who lived in severely affected coastal communities in Manadkadu (northern coast), Kosgoda (western coast), and Galle (southern coast) in Sri Lanka. The prevalence rate of tsunami-related posttraumatic stress disorder (PTSD) (ignoring the time criterion) ranged between 14% and 39% and an additional 5% to 8% had PTSD unrelated to the tsunami. The PTSD symptoms were explained by the severity of the trauma exposure and family loss, as well as previous traumatic events. The results confirm the relevance of the individual history of traumatic events for the genesis of PTSD and indicate a high need of mental health assistance among the tsunami-affected children in Sri Lanka.

[Hemivertebra resection in congenital scoliosis -- early correction in young children]

BACKGROUND

Congenital scoliosis due to hemivertebrae usually progresses during further growth and leads to severe deformities. Early correction in young children is therefore required.

PATIENTS

Thirty-six hemivertebrae in 33 children aged 1 to 6 years (average 3 years 5 months) underwent surgical intervention. Mean follow-up was 4.5 years (2 months to 13 years).

METHODS

The hemivertebra was resected by a posterior approach. The gap after resection was closed by compression via a transpedicular instrumentation, thus correcting the scoliotic deformity.

RESULTS

Mean Cobb angle of the main curve was 45.9 degrees preoperatively, 11.9 degrees postoperatively, and 9.9 degrees at latest follow-up. The compensatory cranial curve improved spontaneously from 18.4 degrees preoperatively to 5.0 degrees postoperatively and 3.7 degrees at latest follow-up. The compensatory caudal curve improved from 21.3 degrees to 6.7 and 5.4 degrees. The angle of kyphosis was 22.8 degrees preoperatively, 8.9 degrees postoperatively, and 6.8 degrees at latest follow-up. There was one infection, 2 pedicle fractures, and 3 implant failures. In 3 patients additional operations were performed due to new developing deformities.

CONCLUSION

Correction surgery of congenital scoliosis should be performed early before the development of severe local deformities and secondary structural changes. Posterior resection of the hemivertebrae with transpedicular instrumentation allows for early intervention in very young children. Excellent correction in both the frontal and sagittal planes, and a short segment of fusion allow for normal growth in the unaffected parts of the spine.

[Preoperative planning and computer assisted surgery in ankylosing spondylitis]

AIM

The following study describes a technique for preoperative planning and computer-assisted correction osteotomy in the treatment of ankylosing spondylitis. The effect on the overall sagittal profile is evaluated.

METHOD

Kyphosis was corrected by a posterior closing wedge osteotomy. Angle and localisation of the wedge were exactly planned preoperatively and transferred to a navigation system. The osteotomy was then performed along the premarked lines with image-guided tools. Nine patients aged 40 to 61 years (average 46 years) were operated on. Follow-up time averaged 12 months (1 to 33 months).

RESULTS

The planned angle of the wedge osteotomy was an average of 30 degrees (range 24 degrees to 40 degrees ) preoperatively. Postoperatively, the angle averaged 30 degrees as well (range 22 degrees to 41 degrees ). The individual difference between real and planned angle was an average of 2.7 degrees (range 1 degrees to 6 degrees ). Sacral inclination was 23 degrees preoperatively (range-- 6 degrees to 40 degrees ) and was corrected to 40 degrees (range 27 degrees to 49 degrees ). Anterior displacement of the gravity line averaged 112 mm preoperatively (range 47 to 196 mm) and was corrected to 31 mm (range--7 to 135 mm) postoperatively and 38 mm (range-- 21 to 137 mm) at latest follow-up.

CONCLUSION

Precise preoperative planning and correction osteotomy exactly according to this planning allow for an excellent correction of the sagittal profile even in severe ankylosing spondylitis. Pelvic tilt and gravity line are normalised, the patient is able to adopt an ergonomic upright position. Navigation facilitates the intraoperative transfer of the preoperative planning.

Anatomische Reposition und monosegmentale Fusion bei hochgradiger dysplastischer Spondylolisthese L5/S1

INTRODUCTION

Developmental spondylolisthesis leads to lumbosacral kyphosis with retroversion of the sacrum and lumbar hyperlordosis. The overall sagittal profile of the spine is affected. The deformity is progressive during growth. This retrospective study describes a technique for complete reduction with clinical and radiological evaluation.

PATIENTS

Thirty-four patients (mean age 16 years 3 months, 10 males, 24 females) with severe developmental spondylolisthesis L5/S1 (Meyerding grades 3 to 5) were operated on between February 1997 and July 2002.

METHOD

Reduction was achieved by temporary transpedicular instrumentation of L4. These screws were removed at the end of the operation or 12 weeks later.

RESULTS

Mean slippage was corrected from 76 % preoperatively to 10 % postoperatively. Segmental kyphosis L5/S1 improved from + 21 degrees preoperatively to - 7 degrees postoperatively. Sacral inclination was 34 degrees preoperatively, 43 degrees postoperatively, and 47 degrees at latest follow-up. 76 % of the patients were pain free at the latest follow-up. In 4 patients a fusion at L4/5 was performed due to subsequent decompensation.

CONCLUSION

The technique described allows for a nearly anatomic reduction with correction of slippage as well as segmental kyphosis. Correction of the local deformity with monosegmental fusion L5/S1 improves dramatically the overall sagittal profile of the spine. Fusion of the primarily healthy segment L4/5 can be avoided.

Prävalenz der Posttraumatischen Belastungsstörung (PTSD) und Möglichkeiten der Ermittlung in der Asylverfahrenspraxis

Zusammenfassung. Theoretischer Hintergrund: Posttraumatische Belastungsstörungen (PTSD) spielen in der Asylverfahrenspraxis eine zunehmende Rolle. Dennoch liegen bislang keine Daten zur Prävalenz unter Asylbewerbern in Deutschland vor. Auch ist nicht bekannt, inwieweit Einzelentscheider des Bundesamtes für die Anerkennung ausländischer Flüchtlinge (BAFl) Anzeichen auf eine Traumatisierung bei der Anhörung erkennen können. Fragestellungen: Stellt PTSD eine relevante Größe unter Asylbewerbern in Deutschland dar? Können Einzelentscheider mit Hilfe von Kurzinstrumenten Anzeichen auf eine PTSD erkennen? Methode: eigens geschulte Einzelentscheider befragten 76 Asyl-Erstantragsteller mit der eng am DSM-IV orientierten PDS (Posttraumatic Diagnostic Scale). 42 dieser Personen wurden in einem klinisch strukturierten Interview anhand der Sektion N des M-CIDI ausführlich nachuntersucht. Ergebnisse: Bei Asylsuchenden beträgt die PTSD-Punkt-Prävalenz ca. 40%. Es ergab sich keine überzufällige Erkennung dieser psychischen Erkrankung durch die Einzelentscheider. Schlussfolgerungen: Die Posttraumatische Belastungsstörung tritt bei Asylbewerbern in Deutschland deutlich häufiger auf als bisher angenommen. Die Schwierigkeit, traumatische Erfahrungen und resultierende PTSD-Symptome im Rahmen der Erstanhörung durch geschulte Mitarbeiter des BAFl zu erkennen, weist auf eine gewisse Verbesserungswürdigkeit der Verfahrensökononie des Asylverfahrens hin.

[One decade of functional imaging in schizophrenia research. From visualisation of basic information processing steps to molecular-genetic oriented imaging]

Modern neuroimaging techniques such as magnetic resonance imaging (MRI) and positron emission tomography (PET) have contributed tremendously to our current understanding of psychiatric disorders in the context of functional, biochemical and microstructural alterations of the brain. Since the mid-nineties, functional MRI has provided major insights into the neurobiological correlates of signs and symptoms in schizophrenia. The current paper reviews important fMRI studies of the past decade in the domains of motor, visual, auditory, attentional and working memory function. Special emphasis is given to new methodological approaches, such as the visualisation of medication effects and the functional characterisation of risk genes.

Should a low prevalence of asymptomatic Chlamydia trachomatis infection in gay men attending HIV clinics discourage from opportunistic screening?

Genitourinary (GU) medicine notifications for homosexually acquired Chlamydia trachomatis (CT) infections show a 414% increase from 1996 to 2002. However, little is known about the prevalence of CT in men who have sex with men (MSM) outside GU medicine settings. Behavioural studies show that MSM with diagnosed HIV infection continue to engage in high-risk sexual behaviour with the risk for sexually transmitted infections (STI) acquisition and HIV transmission. This study analysed the results of urine-based CT screening in MSM attending a London HIV clinic in order to inform local policy on the benefit and patients' acceptability of opportunistic screening. Among men screened, 1.9% (2/107) had asymptomatic CT infection. Screening was well accepted and practical to be implemented in the clinic routine. It is unclear whether isolated routine urine screening is cost effective in the context of HIV prevention. HIV clinics should incorporate a public health perspective and actively contribute to HIV prevention by addressing sexual health and scope opportunities for STI screening.

Molecular markers reveal extensive intraspecific below-ground overlap of silver fir fine roots

Fine roots are expected to be important determinants of plant competition, but very little is known about the extent of root system overlap. Here, we describe the application of two highly variable plastide microsatellites to study the fine root distribution of tree individuals in a silver fir forest. We demonstrate that the spread of fine roots exceeds the width of above-ground parts, and that fine root overlaps among neighbouring trees are extensive both laterally and in depth. This approach will help to improve models of below-ground competition and will facilitate estimations of fine root biomass and thus of below-ground C pools.

Bildgebende Darstellung neurokognitiver Dysfunktionen bei der Aufmerksamkeitsdefizit-/Hyperaktivit�tsst�rung

Attention Deficit Hyperactivity Disorder (ADHD) is a neurobiological disorder of early childhood onset. Defining symptoms are chronic impairments of attention, impulse control and motor hyperactivity that frequently persist until adulthood. Miscellaneous causes of the disorder have been discussed. Accumulating evidence from imaging- and molecular genetic studies strengthened the theory of ADHS being a predominantly inherited disorder of neurobiological origin. In the last 15 years, non-invasive brain imaging methods were successfully implemented in pediatric research. Functional magnetic resonance imaging studies gave major insight into the neurobiological correlates of executive malfunction, inhibitory deficits and psychomotoric soft signs. These findings are in good accordance with brain morphometric data indicating a significant volumetric decrease of major components of striato-thalamo-cortical feedback loops, primarily influencing prefrontal executive functioning (e.g. basal ganglia). Empirical evidence points to a broad array of associated behavioral disturbances like deficient visuomotor abilities and oculomotor dysfunctions. This paper reviews the current empirical evidence derived from prior imaging studies. Special emphasis is given to the relevance of oculomotor dysfunctions in clinical and research settings, as well as their assessment in the MR environment.