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Introduction Stroke and its long-term consequences pose major challenges for the lives of those affected and healthcare systems. Neurological rehabilitation therefore primarily attempts to improve function in order to increase independence in activities of daily living, and to enable social participation. There is only scarce data on dynamics of functional recovery after patients discharge from inpatient neurological rehabilitation. Even less is known about the patient’s perspective on long-term recovery from stroke. The Interdisciplinary Platform for Rehabilitation Research and Innovative Care of Stroke Patients (IMPROVE) aims to address this knowledge gap by providing new insights into the dynamics and extent of functional recovery from stroke beyond inpatient rehabilitation treatment. Methods We provide the protocol for an observational, longitudinal, multicenter study conducted in an Universitary Stroke Center in cooperation with five Neurological Rehabilitation Centers in Northern Germany. Patients who suffered from ischemic or hemorrhagic stroke will be enrolled by the end of inpatient rehabilitation and followed up to 1 year. In addition, a group of chronic stroke patients and a group of craniocerebral trauma patients will be enrolled as a comparison group. Data on stroke characteristics, vascular risk factors, co-morbidities, social support, and demographics will be recorded. Comprehensive clinical evaluation will be performed at baseline, three, six, and twelve months after enrollment. The assessments and scores used reflect the three components of the International Classification of Functioning, Disability and Health (ICF), some of them are tests regularly used in rehabilitation settings. Tests of motor function, cognition, and mood are included, as are tests of self-reported health-related quality of life. Primary outcome measure is a hand motor score, built by the sum of the hand items of the Fugl-Meyer Assessment as an objective measurement of hand function at 12 months after enrollment. Predictors of the primary outcome will be analyzed using linear regression analysis. Perspective The results of IMPROVE will inform about the long-term dynamics of functional stroke recovery after patients’ discharge from inpatient rehabilitation and will provide insights into the association of clinical and demographic factors with recovery of function. Trial registration The protocol is registered at ClinicalTrials.gov (NCT04119479).

Synaptic inhibition can be viewed as a counterbalance of synaptic excitation. However, mul-tiple recent studies at the cellular and network level show that inhibition serves a variety of additional, highly specific functions in the mammalian nervous system. At the molecular and cellular level, inhibitory synapses express diverse postsynaptic reversal potentials, kinetics, plasticity, and pharmacological modulation. This heterogeneity corresponds to the complexity of inhibition at the network level, where interneurons are now perceived as diverse and highly specific organizers of coherent activity patterns. We review some important new developments in the molecular, cellular and network physiology of inhibition. It turns out that understanding inhibition is a key to understanding neuronal network behaviour and, ultimately, may provide important clues for the development of novel therapeutic strategies in neuro-psychiatric diseases.

The metabolism of IgG has been studied in nine patients, who were on long-term treatment in bed for cerebral damage and who were practically unable to move. The amount of circulating IgG was slightly increased, but IgG catabolism calculated by three methods—the U/P method, whole-body counting, and Matthews' method—was significantly increased. The extravascular distribution of IgG was increased and the extravascular/intravascular quotient was 2.0 and differed highly significantly from the quotient of 0.9 in healthy controls. The cause of the increased metabolism of IgG and the altered distribution are discussed with special reference to the influence of posture on the results.

Neurons form transiently stable assemblies that may underlie cognitive functions, including memory formation. In most brain regions, coherent activity is organized by network oscillations that involve sparse firing within a well-defined minority of cells. Despite extensive work on the underlying cellular mechanisms, a fundamental question remains unsolved: how are participating neurons distinguished from the majority of nonparticipators? We used physiological and modeling techniques to analyze neuronal activity in mouse hippocampal slices during spontaneously occurring high-frequency network oscillations. Network-entrained action potentials were exclusively observed in a defined subset of pyramidal cells, yielding a strict distinction between participating and nonparticipating neurons. These spikes had unique properties, because they were generated in the axon without prior depolarization of the soma. GABA A receptors had a dual role in pyramidal cell recruitment. First, the sparse occurrence of entrained spikes was accomplished by intense perisomatic inhibition. Second, antidromic spike generation was facilitated by tonic effects of GABA in remote axonal compartments. Ectopic spike generation together with strong somatodendritic inhibition may provide a cellular mechanism for the definition of oscillating assemblies.

This chapter describes an unconventional signalling mechanisms underlying fast, coherent network activity: inter-axonal electrical coupling. Based on experimental findings and computer models, electrical junctions between axons of pyramidal cells have been suggested to mediate antidromic action potentials. The low capacitance and hlgh excitability of axons enables extremely fast transfer of spikes from the primary axon to the coupled fibre, supporting fast synchronization of neuronal activity. Direct spike transfer between axons does also uncouple the output path from synaptic excitation in the dendrites, thereby constituting a largely autonomous output network for selected groups of coupled neurons. This may turn out to be a unique mechanism of network activity which may be important, for example, in memory readout and consolidation. Axonal gap junctions are notoriously difficult to study experimentally, due to the small size, the lack of selective pharmacological tools and compensatory mechanisms on constitutive connexin deletion mutants. However, combined efforts from different groups have gathered accumulating functional and structural evidence in support of axo-axonic gap junctions. They may, therefore, be important functional determinants of coherent output in neuronal networks.

An emulsion of perfluorotributylamine (Fluosol-43) was used as substitute for the gas-carrying function of erythrocytes in a synthetic medium for perfusion of isolated rat liver. The efficiency and effect of this synthetic gas-carrier were evaluated from measurements of the concentrations of rat albumin, the unsaturated vitamin B12-binding capacity of small-molecular-size vitamin B12-binding proteins (UBBC of SBP), urea nitrogen, glucose, sodium, potassium, alanine amino transferase (ALAT) in the medium, and the incorporation of 14C-lysine into the circulating proteins. Secretion of bile, portal pressure, PO2, PCO2 and pH in the affluent and the effluent mediums were also measured. The results demonstrate that the oxygen-carrying capacity of the medium and the metabolic functions of the liver were higher, and the liver damage less, when the medium included Fluosol-43 than without it. The albumin synthesis and the secretion of bile were as high as has been reported for perfusions with erythrocytes. This indicates that the oxygen carried by the Fluosol-43 was utilised by the liver, and that the metabolic functions were not adversely affected during 4 h of perfusion by the medium containing Fluosol-43.

A fluorocarbon emulsion FC-80 has been used as a substitute for erythrocytes in a synthetic nutrition medium in in vitro perfusions of isolated rat livers. The rate of albumin synthesis was estimated. After the first hour albumin was synthesised at a constant rate of 0.52 + 0.17 mg/h per 100 g of the body weight of the liver donor. 14C-lysine was incorporated into the circulating proteins linearly after the first hour. Other parameters tested were: levels of circulating proteins, urea nitrogen, glucose, glutamic-pyruvic transaminase, excretion of bile, weight changes of the liver, and level of glycogen in liver tissue after perfusion. Histological examinations were also performed. The function of the liver was comparable with the findings of other investigators who used whole blood as the perfusate. As far as we are aware this is the first time that a rat liver has been maintained in good functional condition for over 6 hours during in vitro perfusions with a synthetic medium that included an erythrocyte substitute. The method seems to offer great advantages for the study of metabolic processes.

A group of eleven patients with burns exceeding 20% of their body-surface were kept in an environment of air warmed to 32°C (89.6°F) and dried to a relative humidity of approximately 20%. Another group of eleven patients with burns of a similar size were exposed to a normal ward temperature of 22°C (71.6°F) and at a relative humidity of 45%. Compared with the control series, the patients who were treated with warm dry air showed (1) a substantial reduction in basal metabolic rate; (2) a raised rate of evaporation of water from the burned surface; (3) a rapid drying of the burned surface, and (4) a small loss of weight associated with the reduced metabolic rate and an uncomplicated nutritional course.

In order to study the extent and degree of specificity of the removal of circulating noradrenaline (NA) from the blood stream, during a single passage through the vascular beds of the lungs and of the forearm musculature of unanaesthetized, healthy young men, the following radiometric method was used: A misture of 3H-NA with 14C-inulin and 125I-labelled human serum albumin was injected proximally to the bed under study; six serial blood smaples were drawn distally to it, with about 15 s interval, and the disappearance of 3H-NA relatively to that of 14C-inulin and 125I-albumin was determined. 3H-NA was found to be removed from the blood stream in both these vascular beds. However, in the forearm the removal of 3H-NA was much greater, and apparently to a large extent due to specific trapping in the tissues, since the clearance of 3H-NA over the vascular bed of the forearm markedly exceeded that of 14C-inulin. During passage through the lungs removal of 3H-NA was less marked, and apparently largely unspecific, since it was initially essentially equal to that of 14C-inulin. This suggests that removal of circulating ergones of small molecular size, from the blood stream passing through the lungs, may occur initially by unspecific filtration/diffusion. Their subsequent fate would depend on whether the extraluminal tissues, supplied by the lung circulation, possess specific mechanisms for concentrating and/or inactivating each particular compound.

Human subjects exposed to methyl mercury through consumption of fish were studied during and after varying degrees of exposure. Methyl mercury made up half or less of the blood cell total mercury in “normal” subjects. The proportion was higher in heavily exposed subjects. There was a relationship between exposure to methyl mercury by ingestion of fish and blood mercury levels, and between mercury levels in blood and hair. No symptoms and signs indicating methyl mercury poisoning were observed in subjects exposed at most to 0.8 mg of mercury as methyl mercury per day and having mercury levels of up to 1,200 ng/gm blood cells and 185,000 ng/gm hair. After the end of exposure, biologic half-life of mercury was 33 to 120 days in hair and 99 to 120 days in blood cells in five and two subjects, respectively.