Contrasting responses of above- and belowground diversity to multiple components of land-use intensity

Land-use intensification is a major driver of biodiversity loss. However, understanding how different components of land use drive biodiversity loss requires the investigation of multiple trophic levels across spatial scales. Using data from 150 agricultural grasslands in central Europe, we assess the influence of multiple components of local- and landscape-level land use on more than 4,000 above- and belowground taxa, spanning 20 trophic groups. Plot-level land-use intensity is strongly and negatively associated with aboveground trophic groups, but positively or not associated with belowground trophic groups. Meanwhile, both above- and belowground trophic groups respond to landscape-level land use, but to different drivers: aboveground diversity of grasslands is promoted by diverse surrounding land-cover, while belowground diversity is positively related to a high permanent forest cover in the surrounding landscape. These results highlight a role of landscape-level land use in shaping belowground communities, and suggest that revised agroecosystem management strategies are needed to conserve whole-ecosystem biodiversity.

The Amsterdam Healthy Weight Approach: A whole systems approach for tackling child obesity in cities

In search for successful overweight and obesity prevention, extensive research has shown that programs focused on individual behavior change are not effective enough. Many of the underlying determinants of overweight and obesity have social, environmental and economic origins, and extend even beyond the influence of the health sector and public health. This calls for a whole systems approach that covers a multi-sectoral, multi-stakeholder collaboration, where communities, professionals, government and industry are involved and are all part of the solution.

The Amsterdam Healthy Weight Approach (AHWA), initiated in 2012, is a local government led approach that has the objective to encourage healthy weight for children in a healthy environment. With a long-term vision, aimed at lasting change, the AHWA aims at developing interventions, changing policies and educating and informing both professionals and target groups within the communities that are most heavily burdened with the issue of child obesity (and related complex health/wellbeing issues). The strength of the AHWA lies in adopting a whole systems approach (WSA), in which the key is, to collaborate in an integrated, multi-level, multi sectoral way, with a variety of stakeholders from within and outside the field of public health.

The aim of the presentation is to inform participants from cities around the globe about the success factors, lessons learned and valuable elements of implementing the AHWA, and to provide tools which they can use in discussing their own approaches and bring these to a higher level of effectiveness

Direct and indirect effects of land-use intensification on ant communities in temperate grasslands

Land-use intensification is a major driver of local species extinction and homogenization. Temperate grasslands, managed at low intensities over centuries harbored a high species diversity, which is increasingly threatened by the management intensification over the last decades. This includes key taxa like ants. However, the underlying mechanisms leading to a decrease in ant abundance and species richness as well as changes in functional community composition are not well understood. We sampled ants on 110 grassland plots in three regions in Germany. The sampled grasslands are used as meadows or pastures, being mown, grazed or fertilized at different intensities. We analyzed the effect of the different aspects of land use on ant species richness, functional trait spaces, and community composition by using a multimodel inference approach and structural equation models. Overall, we found 31 ant species belonging to 8 genera, mostly open habitat specialists. Ant species richness, functional trait space of communities, and abundance of nests decreased with increasing land-use intensity. The land-use practice most harmful to ants was mowing, followed by heavy grazing by cattle. Fertilization did not strongly affect ant species richness. Grazing by sheep increased the ant species richness. The effect of mowing differed between species and was strongly negative for Formica species while Myrmica and common Lasius species were less affected. Rare species occurred mainly in plots managed at low intensity. Our results show that mowing less often or later in the season would retain a higher ant species richness-similarly to most other grassland taxa. The transformation from (sheep) pastures to intensively managed meadows and especially mowing directly affects ants via the destruction of nests and indirectly via loss of grassland heterogeneity (reduced plant species richness) and increased soil moisture by shading of fast-growing plant species.

Nutrient stoichiometry and land use rather than species richness determine plant functional diversity

Plant functional traits reflect individual and community ecological strategies. They allow the detection of directional changes in community dynamics and ecosystemic processes, being an additional tool to assess biodiversity than species richness. Analysis of functional patterns in plant communities provides mechanistic insight into biodiversity alterations due to anthropogenic activity. Although studies have consi-dered of either anthropogenic management or nutrient availability on functional traits in temperate grasslands, studies combining effects of both drivers are scarce. Here, we assessed the impacts of management intensity (fertilization, mowing, grazing), nutrient stoichiometry (C, N, P, K), and vegetation composition on community-weighted means (CWMs) and functional diversity (Rao's Q) from seven plant traits in 150 grasslands in three regions in Germany, using data of 6 years. Land use and nutrient stoichiometry accounted for larger proportions of model variance of CWM and Rao's Q than species richness and productivity. Grazing affected all analyzed trait groups; fertilization and mowing only impacted generative traits. Grazing was clearly associated with nutrient retention strategies, that is, investing in durable structures and production of fewer, less variable seed. Phenological variability was increased. Fertilization and mowing decreased seed number/mass variability, indicating competition-related effects. Impacts of nutrient stoichiometry on trait syndromes varied. Nutrient limitation (large N:P, C:N ratios) promoted species with conservative strategies, that is, investment in durable plant structures rather than fast growth, fewer seed, and delayed flowering onset. In contrast to seed mass, leaf-economics variability was reduced under P shortage. Species diversity was positively associated with the variability of generative traits. Synthesis. Here, land use, nutrient availability, species richness, and plant functional strategies have been shown to interact complexly, driving community composition, and vegetation responses to management intensity. We suggest that deeper understanding of underlying mechanisms shaping community assembly and biodiversity will require analyzing all these parameters.

Occipital Nerve Blockade in Chronic Cluster Headache Patients and Functional Connectivity Between Trigeminal and Occipital Nerves

Headache syndromes often involve occipital and neck symptoms, suggesting a functional connectivity between nociceptive trigeminal and cervical afferents. Although reports regarding effective occipital nerve blockades in cluster headache exist, the reason for the improvement of the clinical symptoms is not known. Using occipital nerve blockade and nociceptive blink reflexes, we were able to demonstrate functional connectivity between trigeminal and occipital nerves in healthy volunteers. The R2 components of the nociceptive blink reflex and the clinical outcome in 15 chronic cluster headache patients were examined before and after unilateral nerve blockade of the greater occipital nerve with 5 ml prilocain (1%) on the headache side. In contrast to recent placebo-controlled studies, only nine of the 15 cluster patients reported some minor improvement in their headache. Six patients did not report any clinical change. Exclusively on the injection side, the R2 response areas decreased and R2 latencies increased significantly after the nerve blockade. These neurophysiological and clinical data provide further evidence for functional connectivity between cervical and trigeminal nerves in humans. The trigeminocervical complex does not seem to be primarily facilitated in cluster headache, suggesting a more centrally located pathology of the disease. However, the significant changes of trigeminal function as a consequence of inhibition of the greater occipital nerve were not mirrored by a significant clinical effect, suggesting that the clinical improvement of occipital nerve blockades is not due to a direct inhibitory effect on trigeminal transmission.

Alexithymic and somatisation scores in patients with temporomandibular pain disorder correlate with deficits in facial emotion recognition

Current studies suggest dysfunctional emotional processing as a key factor in the aetiology of temporomandibular disorder (TMD). Investigating facial emotion recognition (FER) may offer an elegant and reliable way to study emotional processing in patients with TMD. Twenty patients with TMD and the same number of age-, sex- and education-matched controls were measured with the Facially Expressed Emotion Labelling (FEEL) test, the 26-item Toronto Alexithymia Scale (TAS-26), the Screening for Somatoform Symptoms (SOMS-2a), the German Pain Questionnaire and the 21-item Hamilton Depression Rating Scale (HAMD). The patients had significantly lower Total FEEL Scores (P = 0·021) as compared to the controls, indicating a lower accuracy of FER. Furthermore, we were able to demonstrate significant group differences with respect to the following issues: patients were more alexithymic (P = 0·006), stated more somatoform symptoms (P < 0·004) and had higher depressive scores in the HAMD (P < 0·003). The factors alexithymia and somatisation could explain 31% (adjusted 27%) of the variance of the FEEL Scores in the sample. The estimation of the standardised regression coefficients suggests an equivalent influence of TAS-26 and SOMS-2a on the FEEL Scores, whereas 'group' (patients versus healthy controls) and depressive symptoms did not contribute significantly to the model. Our findings highlight FER deficits in patients with TMD, which are partially explained by concomitant alexithymia and somatisation. As suggested previously, impaired FER in patients with TMD may further point to probable aetiological proximities between TMD and somatoform disorders.

Effects of acupuncture needle penetration on motor system excitability

OBJECTIVES

Transcranial magnetic stimulation (TMS) studies reported changes in motor evoked potential amplitude after acupuncture needling both at traditional acupoints and non-acupoints. However, the effects of needle penetration per se have not yet been investigated with TMS. The present study aimed at exploring effects of deep manual acupuncture needling compared to a state-of-the-art, non-penetrating control condition on several standard TMS measures of motor system excitability.

METHODS

Twenty healthy volunteers received both verum and sham acupuncture applied at the acupoint GB 34 near the right knee, using a crossover design. A needle with a retractable tip ("Streitberger needle") was used as sham condition to minimize non-specific effects. TMS parameters (resting motor threshold, active motor threshold, cortical silent period, short intracortical inhibition, and intracortical facilitation) were calculated from the abductor digiti minimi (ADM) of both hands 15 min before and after needling by a researcher blind to the treatment condition.

RESULTS

Verum compared to sham acupuncture significantly increased resting motor threshold. No significant treatment effect was found for any other measure, though cortical silent period and intracortical facilitation showed trends to increase in the hemisphere contralateral to the needling site after verum acupuncture.

CONCLUSIONS

These results suggest a subtle but specific inhibitory effect of acupuncture needle penetration at acupoint GB 34 on motor system excitability. Further investigations should be performed with a particular emphasis on the measurements of resting motor threshold, cortical silent periods and intracortical facilitation.

Antibodies to native myelin oligodendrocyte glycoprotein in children with inflammatory demyelinating central nervous system disease

OBJECTIVE

Myelin oligodendrocyte glycoprotein (MOG) is a candidate target antigen in demyelinating diseases of the central nervous system (CNS). Although MOG is encephalitogenic in different animal models, the relevance of this antigen in human autoimmune diseases of the CNS is still controversial.

METHODS

We investigated the occurrence and biological activity of antibodies to native MOG (nMOG) in 47 children during a first episode of CNS demyelination (acute disseminated encephalomyelitis [ADEM], n = 19 and clinical isolated syndrome [CIS], n = 28) by a cell-based bioassay.

RESULTS

High serum immunoglobulin G (IgG) titers to nMOG were detected in 40% of children with CIS/ADEM but 0% of the control children affected by other neurological diseases, healthy children, or adults with inflammatory demyelinating diseases, respectively. By contrast, IgM antibodies to nMOG occurred in only 3 children affected by ADEM. Children with high anti-nMOG IgG titer were significantly younger than those with low IgG titer. Anti-nMOG IgG titers did not differ between the ADEM and CIS group, and did not predict conversion from CIS to MS during a mean 2-year follow-up. However, intrathecal IgG anti-MOG antibody synthesis was only seen in CIS children. IgG antibodies to nMOG not only bound to the extracellular domain of nMOG, but also induced natural killer cell-mediated killing of nMOG-expressing cells in vitro.

INTERPRETATION

Overall, these findings suggest nMOG as a major target of the humoral immune response in a subgroup of children affected by inflammatory demyelinating diseases of the CNS. Children may provide valuable insight into the earliest immune mechanisms of CNS demyelination.

[Impact of physiotherapy, massages and lymphatic drainage in migraine therapy]

Physical treatment, spinal manipulative therapy and massages are often recommended to treat migraine as a prophylactic therapy. Clinical experience and theoretical concepts support their usefulness. However, data on these therapies are scarce. On the basis of the available studies, it is impossible to determine whether or not these therapies are effective. There is a lack of well-designed prospective, randomized controlled trials with a sufficiently long follow-up to observe these therapies. Due to the high acceptance of physical treatment on the one hand and preconceptions about drug treatment on the other, these types of therapies may be an alternative option for some patients if their efficacy is established. A cost-benefit analysis of theses therapies should consider the long amount of time required for them compared with drug intake.

Low-Frequency Short-Time Nociceptive Stimulation of the Greater Occipital Nerve does not Modulate the Trigeminal System

Occipital stimulation in a small group of refractory chronic migraine and cluster headache patients has been suggested as a novel therapeutic approach with promising results. In an earlier study we have shown that a drug-induced block of the greater occipital nerve (GON) inhibits the nociceptive blink reflex (nBR). Now, we sought to examine the effects of low-frequency (3 Hz) short-time nociceptive stimulation of the GON on the trigeminal system. We recorded the nBR responses before and after stimulation in 34 healthy subjects. Selectivity of GON stimulation was confirmed by eliciting somatosensory evoked potentials of the GON upon stimulation. In contrast to an anaesthetic block of the occipital nerve, no significant changes of the R2-latencies and R2-response areas of the nBR can be elicited following GON stimulation. Various modes of electrical stimulation exist with differences in frequency, stimulus intensity, duration of stimulation and pulse width. One explanation for a missing modulatory effect in our study is the relatively short duration of the stimulation.

[Exercise in migraine treatment. Review and discussion of clinical trials and implications for further trials]

Regular exercise is recommended in general treatment guidelines for migraine. However, scientific evidence in support of this recommendation is weak. The majority of available trials on this topic do not meet modern requirements for randomized clinical trials. Often the diagnosis of migraine is not certain, the duration of treatment is too short, and the intervention is not clearly defined; furthermore, the control of treatment is insufficient. The study results are controversial regarding the efficiency of sports intervention in migraine. Regular exercises may have specific effects on the course of disease in migraine through increase of fitness or relaxing effects. It remains unclear whether exercise alone is efficient in migraine treatment or only as part of a more multidisciplinary program. Theoretical considerations, the available limited studies, and clinical experience suggest that exercise may have an effect on migraine, but the present knowledge does not fulfill the needs of evidence-based medicine. Future studies should adhere to the rules for randomized clinical trials in pharmacological migraine prophylaxis.

Sumatriptan and corneal reflexes in headache-free migraine patients: a randomized and placebo-controlled crossover study

A temporary sensitization of central trigeminal neurones in migraine patients during acute attacks has been described in previous studies using the electrically evoked nociceptive blink reflex. The cornea is innervated by small myelinated A-delta and unmyelinated C-fibres only. Stimulation with air puffs activates peripheral nociceptors and allows the investigation of peripheral trigeminal nerve structures. Our objective was to investigate whether corneal reflex examinations with air puff stimulation detect abnormalities in migraineurs during their pain-free interval and if the corneal reflex may be modulated by the administration of an oral triptan. After validation of the nociceptive air puff technique by investigating the corneal reflexes before and after a local anaesthesia of the cornea, we recorded corneal reflexes in 25 migraineurs during their pain-free period and 25 healthy controls before and after the oral administration of 100 mg sumatriptan in a randomized, placebo-controlled, crossover study. Baseline response areas under the curve (AUCs) and latencies of the R2 components of the corneal reflexes did not show any significant differences between patients and controls. Patients did not show any significant differences regarding their headache and non-headache side. The use of an oral triptan had no significant influence on latencies or AUCs in both patients and controls. Our data suggest that there is no facilitation of the trigeminal system in the headache-free interval among patients with migraine. The stable corneal reflexes after the oral administration of 100 mg sumatriptan suggest that there was no inhibition of the trigeminal system, both in patients during their headache-free period and in healthy controls.

Monitoring of ketogenic diet for carnitine metabolites by subcutaneous microdialysis

The ketogenic diet (KD) provides ketones from the degradation of free fatty acids for energy metabolism. It is a therapeutic option for pharmacoresistant epilepsies. Carnitine is the carrier molecule that transports fatty acids across the mitochondrial membrane for degradation into ketones. The integrity of this transport system is a prerequisite for an adequate ketogenic response. For monitoring of tissue metabolism with KD, we used the sampling method of s.c. microdialysis (MD), which permits minimally invasive, frequent, and extensive metabolic monitoring independent of blood tests. By using this new method, we monitored changes in carnitine metabolism induced by KD, particularly in free carnitine (C0), acetylcarnitine (C2), and hydroxybutyrylcarnitine (C4OH). Correlation of microdialysate and tissue concentrations for carnitines in vitro was about 85%. Carnitine metabolism was monitored in seven children started on a KD for pharmacoresistant epilepsy after a conventional initial fasting period. Detected metabolic changes consisted of a slight decrease in s.c. C0 and a marked increase in C2/CO and C4OH/CO levels. The levels of s.c. C4OH strongly correlate with beta-hydroxybutyrate (beta-OHB) levels in plasma providing an additional parameter for the carnitine reserve of the body and reflect an optimal ketogenic energy supply. Subcutaneous MD allows close and extensive monitoring of metabolism with a KD.

Functional connectivity between trigeminal and occipital nerves revealed by occipital nerve blockade and nociceptive blink reflexes

Headache syndromes often suggest occipital and neck involvement, although it is still unknown to what extent branches of segment C1-C3 contribute actively to primary headache. Pain within the occipital area may be referred to the trigeminal territory. However, a modulation of trigeminal transmission by affecting cervical input in humans has not been elucidated so far. A convergence of cervical and trigeminal input at the level of the caudal part of the trigeminal nucleus in the brainstem has been suggested due to anatomical and neurophysiological studies in animals. We examined the R2 components of the nociceptive blink reflex responses in 15 healthy subjects before and after unilateral nerve blockade of the greater occipital nerve with 5 ml prilocain (1%). R2 response areas (AUC) decreased and the R2 latencies increased significantly after the nerve blockade only on the side of injection. AUC and latencies on the non-injection side remained stable. Thresholds for sensory or pain perception did not differ significantly between the repeated measurements on both sides. Our findings extend previous results related to anatomical and functional convergence of trigeminal and cervical afferent pathways in animals and suggest that the modulation of this pathway is of potential benefit in primary headache disorders.

Subcutaneous microdialysis for children - safe biochemical tissue monitoring based on a minimal traumatizing no touch insertion technique

BACKGROUND

Microdialysis (MD) enables analysis of extracellular metabolites without performing blood tests. Changes in the concentration of various metabolites can be monitored frequently on almost every type of human tissue. Microdialysis of subcutaneous tissue (sc MD) is of particular significance in the case of pediatric patients because diurnal profiles can be generated without repeated blood sampling. There are only a few scientific articles that describe the application of sc MD on neonates, infants, or children. So far, side effects have not been investigated comprehensively. This prospective study scrutinizes side effects of sc MD in pediatric patients, focusing on a Minimal Traumatizing Insertion Technique of the MD catheter.

PATIENTS AND METHODS

42 pediatric patients within four age categories participated in the study which involved bedside monitoring using sc MD, including 5 extremely low birth weight (ELBW) infants with a body weight <1000g. A total of 48 sc MD catheters were inserted. Selection criteria were risk of hypoglycaemia (n = 29), elevated lactate levels (n = 16), or aminoacidopathies (n = 3). Duration of sc MD ranged from 1 to 16 days. We used a Minimal Traumatizing Insertion Technique to safely insert the MD catheter into the subcutaneous tissue, characterized by blunt dissection of the tissue and by the use of a plastic cannula guidance to avoid desterilisation of the catheter. Complications and side effects related to sc MD were documented in standardized forms.

RESULTS

The MD probe was easily placed even in the scanty adipose tissue of ELBW infants. During insertion of sc MD catheters accidental venous puncture occurred to 8%, and minor bleeding to 27%. Even with local anaesthesia insertion was painful for 40%. During the course of sc MD complications were rare: disturbance of perfusion flow 4%, catheter dislocation 4%, local bleeding 4%. No signs of systemic or local infection were observed, there were no cases of local incompatibility. All catheters were withdrawn completely without leaving a scar. Repeated measurements allowed the generation of diurnal metabolic profiles. In some cases (respiratory chain complex I deficiency, PDH-deficiency) significant therapeutical effects on the patients' metabolism were demonstrated.

CONCLUSIONS

The present study proves long-term sc MD to be suitable and safe for biochemical tissue monitoring. Using our insertion technique, it can be applied to children of all ages without causing discomfort or severe side effects. As it permits frequent sampling it allows evaluating and optimizing therapy and means a substantial progress for pediatric observation.

Der trigeminozervikale Komplex

The activation of the trigeminal nociceptive system is the neural substrate of pain in primary headache syndromes such as migraine and cluster headache. The nociceptive inflow from the meninges to the spinal cord is relayed in brainstem neurones of the trigemino-cervical complex (TCC). Two important mechanisms of pain transmission are reviewed: convergence of nociceptive trigeminal and cervical afferents and sensitization of trigemino-cervical neurones. These mechanisms have clinical correlates such as hyperalgesia, allodynia, spread and referral of pain to trigeminal or cervical dermatomes. Neurones in the TCC are subject to a modulation of pain-modulatory circuits in the brainstem such as the periaqueductal grey (PAG). Recent experimental and clinical findings of a modulation of these pain processes are discussed. The review focuses on TCC neurones as integrative relay neurones between peripheral and central pain mechanisms. The understanding of these mechanisms has implications for the understanding of the clinical phenomenology in primary headache syndromes and the development of therapeutical options.

Selective expression of IL-7 receptor on memory T cells identifies early CD40L-dependent generation of distinct CD8+ memory T cell subsets

Several recent studies have demonstrated that T-helper cell-dependent events during the initial priming period are required for the generation of CD8(+) T cell-mediated protective immunity. The underlying mechanisms of this phenomenon have not yet been determined, mostly because of difficulties in studying memory T cells or their precursor populations at early stages during immune responses. We identified IL-7 receptor (CD127) surface expression as a marker for long-living memory T cells, most importantly allowing the distinction between memory and effector T cells early after in vivo priming. The combination of surface staining for CD127 and CD62L further separates between two functionally distinct memory cell subsets, which are similar (if not identical) to cell subsets recently described as central memory T cells (CD127(high) and CD62L(high)) and peripheral effector memory T cells (CD127(high) and CD62L(low)). Using this new tool of memory T cell analysis, we demonstrate that CD8(+) T cell priming in the absence of T cell help or CD40L specifically alters the generation of the effector memory T cell subset, which appears to be crucial for immediate memory responses and long-term maintenance of effective protective immunity. Our data reveal a unique strategy to obtain information about the quality of long-term protective immunity early during an immune response, a finding that may be applied in a variety of clinical settings, including the rapid monitoring of vaccination success.

Differences in maintenance of CD8+ and CD4+ bacteria-specific effector-memory T cell populations

Our knowledge about the kinetics and dynamics of complex pathogen-specific CD8(+) T cell responses and the in vivo development of CD8(+) memory T cells has increased substantially over the past years; in comparison, relatively little is known about the CD4(+) T cell compartment. We monitored and directly compared the phenotypical changes of pathogen (Listeria monocytogenes)-specific CD8(+) and CD4(+) T cell responses under conditions leading to effective and long-lasting protective immunity. We found that the general kinetics of bacteria-specific CD8(+) and CD4(+) T cells during the effector and post-effector phases are synchronized. However, later during the memory phase, CD8(+) and CD4(+) T cell populations differ substantially. Whereas CD8(+) memory T cell populations with immediate effector function are readily detectable in lymphoid and non-lymphoid tissues and remain remarkably stable in size, antigen-specific CD4(+) effector-memory T cells decline continuously in frequency over time. These findings have important implications for the better understanding of the in vivo development of protective immunity towards intracellular pathogens.

[Trigemino-autonomic headache syndromes]

This review describes the characteristics of some rare severe primary headache syndromes without any structural lesions, which are summarized as the trigemino-autonomic headaches. Pain in these syndromes is associated with autonomic symptoms such as conjunctival injection, lacrimation, rhinorrhoe, ptosis or eyelid edema. This article summarizes the diagnostics, epidemiology and therapy of these conditions.