Accelerated long-term forgetting in patients with acquired brain injury.

OBJECTIVE: Recent research suggests that patients with neurological disorders without overt seizures may also experience accelerated long-term forgetting (ALF). This term describes unimpaired learning and memory performance after standard retention intervals, but an excessive rate of forgetting over delays of days or weeks. The objective of this retrospective study was to investigate ALF in patients with an acquired brain injury (ABI) and to associate memory performance with executive functions. METHODS: Verbal memory performance (short-term recall, 30-min recall, 1-week recall) was assessed in 34 adult patients with ABI and compared to a healthy control group (n = 54) using an auditory word learning and memory test. RESULTS: Repeated measure analysis showed significant effects of time and group as well as interaction effects between time and group regarding recall and recognition performance. Patients with ABI had a significantly impaired 1-week recall and recognition performance compared to the healthy control group. Correlations between recall performance and executive functions were nonsignificant. DISCUSSION: Our results demonstrate that non-epileptic patients with ABI, especially patients with frontal and fronto-temporal lesions, are prone to ALF. Additionally, our data support the assumption that ALF results from a consolidation impairment since verbal recall and recognition were impaired in patients with ABI.

Bullous haemorrhagic dermatitis induced by heparins and other anticoagulants: 94 cases from French pharmacovigilance centres and a literature review.

BACKGROUND: Bullous haemorrhagic dermatitis (BHD) is an uncommon and highly particular side effect of various forms of heparins. METHODS: To better characterise the disease, we collected all cases from French Pharmacovigilance centres recorded over a 20-year period (37 cases) and performed a Medline literature search up to June 2020 (57 cases). RESULTS: In all, 94 patients were identified (male/female ratio: 2.2) of mean age 73.5±12.1 years (31-94). Patients were treated with enoxaparin (n=66), unfractionated heparin (n=11), fondaparinux (n=10), tinzaparin (n=4), bemiparin (n=1), reviparin (n=1), dalteparin (n=1), and 4 with other anticoagulants: warfarin (n=3) and rivaroxaban (n=1). All cases presented with 1 to more than 100 haemorrhagic vesicles and bullae, distant from the injection sites, located mainly on the lower (75%) or upper limbs (69%). The lesions were asymptomatic, except in 5 patients who had pruritic or painful lesions. The interval between treatment initiation and BHD ranged from 6 hours to 30 days (mean: 8.4±7 days). Biopsy (n=53) showed intraepidermal or subcorneal cavity with red cells (n=39) or junctional blisters (n=10), with eosinophilic infiltrate only rarely. Direct immuno-fluorescence was negative in 19/20 cases and indirect immunofluorescence was negative in 8/8. The outcome was favourable in all cases, including in 12 patients for whom heparin was maintained. A 93-year-old patient died of compressive haematomas unrelated to BHD. We found 5 cases similar to BHD due to other anticoagulants. DISCUSSION: This is the largest comprehensive series of this adverse effect due to heparins or, more rarely, to other anticoagulants. Dermatologists must be aware of BHD, since this benign side effect does not necessarily require interruption of treatment. It is rare, considering the large-scale prescription of heparins, and occurs mainly in male patients aged over 70. Although the presentation is highly typical, the physiopathology is difficult to understand, as coagulation parameters are usually normal. Aging, skin fragility or mechanical factors might play a role.

Temperature and moisture are minor drivers of regional-scale soil organic carbon dynamics.

Storing large amounts of organic carbon, soils are a key but uncertain component of the global carbon cycle, and accordingly, of Earth System Models (ESMs). Soil organic carbon (SOC) dynamics are regulated by a complex interplay of drivers. Climate, generally represented by temperature and moisture, is regarded as one of the fundamental controls. Here, we use 54 forest sites in Switzerland, systematically selected to span near-independent gradients in temperature and moisture, to disentangle the effects of climate, soil properties, and landform on SOC dynamics. We estimated two SOC turnover times, based on bulk soil 14C measurements (τ14C) and on a 6-month laboratory soil incubation (τi). In addition, upon incubation, we measured the 14C signature of the CO2 evolved and quantified the cumulated production of dissolved organic carbon (DOC). Our results demonstrate that τi and τ14C capture the dynamics of contrasting fractions of the SOC continuum. The 14C-based τ14C primarily reflects the dynamics of an older, stabilised pool, whereas the incubation-based τi mainly captures fresh readily available SOC. Mean site temperature did not raise as a critical driver of SOC dynamics, and site moisture was only significant for τi. However, soil pH emerged as a key control of both turnover times. The production of DOC was independent of τi and not driven by climate, but primarily by the content of clay and, secondarily by the slope of the site. At the regional scale, soil physicochemical properties and landform appear to override the effect of climate on SOC dynamics.

[Types of pain coping in chronic pain patients]. / Typen der Schmerzverarbeitung bei Patienten mit chronischen Schmerzen.

BACKGROUND: The characterization of subtypes of chronic pain patients based on their pain coping profiles may contribute to a better understanding of the pain syndrome, to more specific indications of established treatment options as well as to further development of therapeutic interventions. OBJECTIVE: The aim of this study was to examine whether different subgroups of chronic pain patients emerge when using the German pain coping questionnaire (FESV) to identify homogeneous subgroups of pain coping patterns. Furthermore, the aim was to examine whether these pain coping subgroups differ in terms of sociodemographic characteristics, as well as pain and treatment-related aspects. MATERIAL AND METHODS: A total of 166 inpatients with a chronic pain disorder according to ICD-10 F45.41 were examined as part of the routine assessment within an interdisciplinary pain treatment program. Cognitive and behavioral pain coping and pain-related psychological impairment were measured with the FESV as components of pain coping. Using cluster analyses, homogeneous patient subgroups were generated on the basis of pain coping data. The resulting subgroups were subsequently compared regarding sociodemographic characteristics, pain-related impairment, global psychological distress, depression, anxiety, perceived stress, utilization of social support and motivation for psychotherapy. RESULTS AND CONCLUSION: The results revealed three distinct subgroups regarding pain coping patterns: (1) high impairment and high coping, (2) low impairment and high coping and (3) high impairment and low coping. The subgroups differed significantly in almost all characteristics, except for pain duration and pain intensity. The categorization into the abovementioned pain coping subtypes may assist clinicians in tailoring pain treatment to the needs and characteristics of the individual patients.

[Psychosocial stressors and pain sensitivity in chronic pain disorder with somatic and psychological factors (F45.41)]. / Psychosoziale Stressoren und Schmerzempfindlichkeit bei chronischer Schmerzstörung mit somatischen und psychischen Faktoren (F45.41).

BACKGROUND: Increased pain sensitivity is characteristic for patients with chronic pain disorder with somatic and psychological factors (F45.41). Persistent stress can induce, sustain, and intensify pain sensitivity, thereby modulating pain perception. In this context, it would be favorable to investigate which psychosocial stressors are empirically linked to pain sensitivity. OBJECTIVES: The aim of this study was to examine the relationship between psychosocial stressors and pain sensitivity in a naturalistic sample of patients with chronic pain disorder with somatic and psychological factors (F45.41). MATERIALS AND METHODS: We assessed 166 patients with chronic pain disorder with somatic and psychological factors (F45.41) at entry into an inpatient pain clinic. Pain sensitivity was measured with a pain provocation test (Algopeg) at the middle finger and earlobe. Stressors assessed were exposure to war experiences, adverse childhood experiences, illness-related inability to work, relationship problems, and potentially life-threatening accidents. Correlation analyses and structural equation modeling were used to examine which stressors showed the strongest prediction of pain sensitivity. RESULTS: Patients exhibited generally heightened pain sensitivity. Both exposure to war and illness-related inability to work showed significant bivariate correlations with pain sensitivity. In addition to age, they also predicted a further increase in pain sensitivity in the structural equation model. CONCLUSIONS: Bearing in mind the limitations of this cross-sectional study, these findings may contribute to a better understanding of the link between psychosocial stressors and pain sensitivity.

Postmitotic control of sensory area specification during neocortical development.

The mammalian neocortex is subdivided into cytoarchitectural areas with distinct connectivity, gene expression and neural functions. Areal identity is initially specified by rostrocaudal and mediolateral gene expression gradients in neuroepithelial and radial glial progenitors (the 'protomap'). On further differentiation, distinct sets of gene expression gradients arise in intermediate progenitors and postmitotic neurons, and are necessary to implement areal specification. However, it is still unknown whether postmitotic gene expression gradients can determine areal identity independently of protomap gradients. Here we show, by cell type-restricted genetic loss- and gain-of-function, that high levels of postmitotic COUP-TFI (Nr2f1) expression are necessary and sufficient for the development of sensory (caudal) areal identity. Our data indicate a crucial role for postmitotic patterning genes in areal specification and reveal an unexpected plasticity in this process, which may account for complex and evolutionarily novel structures characteristic of the mammalian neocortex.

[Does hypersensitivity to multiple drugs really exist?]. / La polysensibilisation médicamenteuse systémique existe-t-elle ?

BACKGROUND: Multiple-drug hypersensitivity (MDH) in the literature concerns different entities. Our objective was to define its frequency and characteristics in patients examined for cutaneous adverse drug reaction (CADR) before studying genetic predisposition. MATERIALS AND METHODS: From a database comprising all patients referred for CADR between 2000 and 2010, we selected those meeting the following criteria: sensitisation to at least two chemically unrelated substances, as confirmed by positive skin tests or challenge tests. The following were excluded: patients with haematological diseases, HIV or chronic wounds and sensitization to the excipients. RESULTS: Of the 1925 patients included, 11 (0.6%) were classed as polysensitized: eight women and three men, of mean age 62 years, presenting 2.5 episodes of drug hypersensitivity per patient. Four cases of DRESS were noted. DISCUSSION: The strict criteria stipulated for this study enabled us to select patients with MDH, and to affirm that while it does in fact exist, it seems rare. Compared to polysensitized patients described in the literature, we preferred to distinguish between three groups of MDH: one occurring with different substances in separate episodes of CADR, one occurring with different substances during the same episode of CADR, and one occurring during DRESS and correlating with viral replication. CONCLUSION: MDH exists and genetic predisposition could be investigated by studying cytokine polymorphism in such patients. However, because of its rarity, it is impossible to rule out fortuitous association of two episodes of CADR in the same patient.

[Hyperhomocysteinemia and leg ulcers: A prospective study of 68 patients]. / Hyperhomocystéinémie et ulcères de jambes : étude prospective de 68 observations.

BACKGROUND: Homocysteine is a sulphur-containing amino acid derived from methionine. Hyperhomocysteinaemia is now recognised as an independent risk factor for occlusive arterial disease and thrombotic venous disease. The aim of this study was to determine the prevalence of hyperhomocysteinemia in patients with leg ulcers. PATIENTS AND METHODS: We prospectively investigated hospitalised patients for vascular leg ulcers between March 2008 and June 2009 at two dermatology centres. We collected details of cardiovascular disease and determined nutritional status by means of the MNA score. Fasting blood samples were taken and analyzed for homocysteine, albumin, prealbumin, folic acid, vitamin B12, creatinine and a complete blood count. RESULTS: Sixty-eight patients were enrolled in the study: 48 women and 20 men. Fifty-three percent of patients had venous leg ulcers, 18% had arterial leg ulcers and 20% had leg ulcers of mixed origin. The prevalence of hyperhomocysteinemia was 56%, with no differences according to ulcer type or gender. DISCUSSION: While the prevalence of hyperhomocysteinemia in our population of leg ulcer patients was high, this descriptive study does not allow us to establish any causal link between hyperhomocysteinemia and leg ulcers. Moreover, since the literature indicates that homocysteine-lowering therapy does not reduce cardiovascular and thromboembolic risk, there appears to be little call for further trials on hyperhomocysteinaemia and leg ulcers.

Gate-controlled spin-orbit interaction in a parabolic GaAs/AlGaAs quantum well.

We study the tunability of the spin-orbit interaction in a two-dimensional electron gas with a front and a back gate electrode by monitoring the spin precession frequency of drifting electrons using time-resolved Kerr rotation. The Rashba spin splitting can be tuned by the gate biases, while we find a small Dresselhaus splitting that depends only weakly on the gating. We determine the absolute values and signs of the two components and show that for zero Rashba spin splitting the anisotropy of the spin-dephasing rate vanishes.

Time-resolved detection of single-electron interference.

We demonstrate real-time detection of self-interfering electrons in a double quantum dot embedded in an Aharonov-Bohm interferometer, with visibility approaching unity. We use a quantum point contact as a charge detector to perform time-resolved measurements of single-electron tunneling. With increased bias voltage, the quantum point contact exerts a back-action on the interferometer leading to decoherence. We attribute this to emission of radiation from the quantum point contact, which drives noncoherent electronic transitions in the quantum dots.

Frequency-selective single-photon detection using a double quantum dot.

We use a double quantum dot as a frequency-tunable on-chip microwave detector to investigate the radiation from electron shot-noise in a near-by quantum point contact. The device is realized by monitoring the inelastic tunneling of electrons between the quantum dots due to photon absorption. The frequency of the absorbed radiation is set by the energy separation between the dots, which is easily tuned with gate voltages. Using time-resolved charge-detection techniques, we can directly relate the detection of a tunneling electron to the absorption of a single photon.

Coronary artery revascularization using both ITAs as free conduits in patients with three-vessel disease--the lambda graft.

BACKGROUND: There is little information on using internal thoracic arteries (ITA) as free conduits in coronary artery bypass grafting. This study examines the results using both ITAs as free grafts in a lambda configuration implanting the common trunk into the ascending aorta. METHODS: Over a 6-year period, 317 patients underwent coronary artery revascularization with both ITAs as free grafts in a lambda configuration. RESULTS: An average of 4.9 distal anastomoses per patient was performed. There were 4 deaths (three early and one late). The mean NYHA class improved from preoperatively 2.8 to 1.1 at the last check. All 16 patients with suspected recurrent angina or a pathologic exercise test were restudied by angiography. Segmental graft stenosis or occlusion was found in 13 (in only one at aortic anastomosis). Five patients underwent late PTCA, and two underwent coronary reoperation. The six-year actuarial survival was 98% (90 % CL+/- 2 %), intervention-free survival 96 % (90 % CL +/- 2 %). CONCLUSION: Revascularization using both ITAs as free grafts in a lambda configuration gives good early and mid-term results for up to 6 years. The aortic ITA anastomosis can be considered safe.

Listeria keratitis in a horse.

Listeria monocytogenes is ubiquitous in the environment but is rarely reported as a cause of keratitis in animals. In this case, a mare was presented with epiphora and evidence of pain in the right eye. Listeria monocytogenes was isolated from a corneal lesion, and bacteria were also seen in the cytologic evaluation. This is the first reported case of ulcerative keratitis associated with L. monocytogenes in a horse.

Initiation of facial motoneurone migration is dependent on rhombomeres 5 and 6.

In mammals, facial branchiomotor (FBM) neurones are born in ventral rhombomere (r) 4 and migrate through r5 to dorsal r6 where they form the facial motor nucleus. This pattern of migration gives rise to the distinctive appearance of the internal genu of the facial nerve, which is lacking in birds. To distinguish between extrinsic cues and intrinsic factors in the caudal migration of FBM neurones, this study takes advantage of the evolutionary migratory difference between mouse and chick in generating mouse-chick chimaeras in ovo. After the homotopic transplantation of mouse r5 and/or r6 into a chick embryo, chick ventral r4 neurones redirected their cell bodies towards the ectopic mouse source and followed a caudal migratory path, reminiscent of mouse FBM neurones. In a second series of grafting experiments, when mouse r4 was transplanted in place of chick r4, mouse r4 neurones were unable to migrate into chick r5, although mouse and chick cells were able to mix freely within r4. Thus, these data suggest that local environmental cues embedded in mouse r5 and r6 are directly involved in initiating caudal migration of FBM neurones. In addition, they demonstrate that chick FBM neurones are competent to recapitulate a migratory behaviour that has been lost during avian phylogeny.