Prevalence of monogenic diabetes in the population-based Norwegian Childhood Diabetes Registry.

AIMS/HYPOTHESIS: Monogenic diabetes (MD) might be misdiagnosed as type 1 diabetes. The prevalence of MD among children with apparent type 1 diabetes has not been established. Our aim was to estimate the prevalence of common forms of MD in childhood diabetes. METHODS: We investigated 2,756 children aged 0-14 years with newly diagnosed diabetes who had been recruited to the nationwide population-based Norwegian Childhood Diabetes Registry (NCDR), from July 2002 to March 2012. Completeness of ascertainment was 91%. Children diagnosed with diabetes who were under12 months of age were screened for mutations in KCNJ11, ABCC8 and INS. Children without GAD and protein tyrosine phosphatase-like protein antibodies were screened in two ways. Those who had a parent with diabetes were screened for mutations in HNF1A, HNF4A, INS and MT-TL1. Children with HbA1c <7.5% (<58 mmol/mol) and no insulin requirement were screened for mutations in GCK. Finally, we searched the Norwegian MODY Registry for children with genetically verified MD. RESULTS: We identified 15 children harbouring a mutation in HNF1A, nine with one in GCK, four with one in KCNJ11, one child with a mutation in INS and none with a mutation in MT-TL1. The minimum prevalence of MD in the NCDR was therefore 1.1%. By searching the Norwegian MODY Registry, we found 24 children with glucokinase-MODY, 15 of whom were not present in the NCDR. We estimated the minimum prevalence of MD among Norwegian children to be 3.1/100,000. CONCLUSIONS/INTERPRETATION: This is the first prevalence study of the common forms of MD in a nationwide, population-based registry of childhood diabetes. We found that 1.1% of patients in the Norwegian Childhood Diabetes Registry had MD.

Health-related quality of life in advanced non-small cell lung cancer: correlates and comparisons to normative data.

The aim was to describe self-reported health-related quality of life (HRQoL) in patients with advanced non-small cell lung cancer and to investigate the associations to stage of disease, age, gender, weight loss and performance status. Further, the study aimed to compare patients' HRQoL with that of the Swedish general population. Data on HRQoL were collected within a multi-centre randomised controlled trial. A total of 334 patients were included between 1998 and 2001. The European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-Core Questionnaire (EORTC QLQ-C30) and Lung Cancer Questionnaire (EORTC QLQ-LC13) were used to assess HRQoL. HRQoL data for comparison with the Swedish population were derived from a random sample of the Swedish population. Patients reported a markedly impaired HRQoL compared to the normal population. There were statistically and clinically significant differences with regard to almost all QLQ-C30 functional and symptom scales. Global health status, physical functioning, role functioning and emotional functioning were markedly deteriorated. The most prominent symptoms were dyspnoea, fatigue, coughing, insomnia, appetite loss and pain. A low performance status, younger age, female gender and a more advanced disease were independently associated with a worse HRQoL. Additional studies are required to gain increased insight into this seriously ill group of patients and their need of supportive care.

Current trends in stroke rehabilitation. A review with focus on brain plasticity.

Current understanding of brain plasticity has lead to new approaches in ischemic stroke rehabilitation. Stroke units that combine good medical and nursing care with task-oriented intense training in an environment that provides confidence, stimulation and motivation significantly improve outcome. Repetitive trans-cranial magnetic stimulation (rTMS), and trans-cranial direct current stimulation (tDCS) are applied in rehabilitation of motor function. The long-term effect, optimal way of stimulation and possibly efficacy in cognitive rehabilitation need evaluation. Methods based on multisensory integration of motor, cognitive, and perceptual processes including action observation, mental training, and virtual reality are being tested. Different approaches of intensive aphasia training are described. Recent data on intensive melodic intonation therapy indicate that even patients with very severe non-fluent aphasia can regain speech through homotopic white matter tract plasticity. Music therapy is applied in motor and cognitive rehabilitation. To avoid the confounding effect of spontaneous improvement, most trials are preformed ≥3 months post stroke. Randomized controlled trials starting earlier after strokes are needed. More attention should be given to stroke heterogeneity, cognitive rehabilitation, and social adjustment and to genetic differences, including the role of BDNF polymorphism in brain plasticity.

Oxytocin levels in the posterior pituitary and in the heart are modified by voluntary wheel running.

We hypothesized that voluntary wheel running results in increased secretion of oxytocin, a peptide involved in the stress response. An additional hypothesis was that prolonged exercise affects oxytocin levels in the heart, which is in line with the potential role of oxytocin in cardiovascular functions. Voluntary wheel running lasted 3 weeks and daily running distances increased progressively reaching maximum levels about 8 km (Sprague-Dawley rats) and 4 km (Lewis strain). The exercise resulted in significant reduction of epididymal fat, slight increase in glucose transporter GLUT4 mRNA levels and significant enhancement of plasma density. Voluntary exercise failed to influence plasma oxytocin levels either in Lewis or Sprague-Dawley rats, but it resulted in a significant decrease of oxytocin concentrations in the posterior pituitary. Plasma oxytocin concentrations were not modified even if the measurements were made in the dark phase of the day. In voluntary wheel running Sprague-Dawley rats, the content of oxytocin in the right heart atrium was lower than in controls. Thus, the present findings demonstrate that prolonged voluntary wheel running results in a decrease in pituitary oxytocin content without evident changes in hormone concentrations in peripheral blood. However, prolonged exercise used has a significant impact on oxytocin levels in the heart.

Effect of environmental enrichment on stress related systems in rats.

The aim of this study was to test whether environmental enrichment alters the status and responsiveness of pituitary-adrenocortical and sympathetic-adrenomedullary hormones in rats. Previous studies have shown that rats kept in an enriched environment differ from those kept in standard cages in dendritic branching, synaptogenesis, memory function, emotionality and behaviour. In male Wistar rats kept in an enriched environment for 40 days, we studied basal concentrations of hormones, endocrine responses to 5-HT(1A) challenge and responsiveness and adaptation to repeated handling. Environmental enrichment consisted of large plexiglass cages with 10 rats per cage, which contained variety of objects exchanged three times a week. Rats kept in this enriched environment had higher resting plasma concentrations of corticosterone, larger adrenals and increased corticosterone release to buspirone challenge compared to controls. Lower adrenocorticotropic hormone, corticosterone and adrenaline responses to handling were noticed in rats kept in an enriched environment. Exposure to repeated handling led to a more rapid extinction of corticosterone responses in rats kept in an enriched environment. Thus, environmental enrichment leads to pronounced changes in neuroendocrine regulation, including larger adrenals and increased adrenocortical function, which are so far considered to be indication of chronic stress.

Effects of postischemic environment on transcription factor and serotonin receptor expression after permanent focal cortical ischemia in rats.

Housing rats in an enriched environment improves functional outcome after ischemic stroke, this may reflect neuronal plasticity in brain regions outside the lesion. Which components of the enriched environment that are of greatest importance for recovery after brain ischemia is uncertain. We have previously found that enriched environment and social interaction alone both improve functional recovery after focal cerebral ischemia, compared with isolated housing with voluntary wheel-running. In this study, the aim was to separate components of the enriched environment and investigate the effects on some potential mediators of improved functional recovery; such as the inducible transcription factors nerve growth factor-induced gene A (NGFI-A) and NGFI-B, and the glucocorticoid and serotonin systems. After permanent middle cerebral artery occlusion, rats were divided into four groups: individually housed with no equipment (deprived group), individually housed with free access to a running wheel (running group), housed together in a large cage with no equipment (social group) or in a large cage furnished with exchangeable bars, chains and other objects (enriched group). mRNA expression of inducible transcription factors, serotonin and glucocorticoid receptors was determined with in situ hybridisation 1 month after cerebral ischemia. Rats housed in enriched or social environments showed significantly higher mRNA expression of NGFI-A and NGFI-B in cortical regions outside the lesion and in the CA1 (cornu ammonis region of the hippocampus), compared with isolated rats with or without a running wheel. NGFI-A and NGFI-B mRNA expression in cortex and in CA1 was significantly correlated to functional outcome. 5-Hydroxytryptamine receptor 1A (5-HT(1A)) mRNA expression and binding, as well as 5-HT(2A) receptor mRNA expression were decreased in the hippocampus (CA4 region) of the running wheel rats. Mineralocorticoid receptor gene expression was increased in the dentate gyrus amongst wheel-running rats. No group differences were found in plasma corticosterone levels or mRNA levels of glucocorticoid receptor, corticotropin-releasing hormone, 5-HT(2C) or c-fos. In conclusion, we have found that social interaction is a major component of the enriched environment regarding the effects on NGFI-A and NGFI-B expression. These transcription factors may be important mediators of improved functional recovery after brain infarctions, induced by environmental enrichment.

Voluntary wheel running modulates glutamate receptor subunit gene expression and stress hormone release in Lewis rats.

Lewis rats that are known to be addiction-prone, develop compulsive running if they have access to running wheels. The present experiments were aimed 1) to evaluate the activation of stress systems following chronic and acute voluntary wheel running in Lewis rats by measurement of hormone release and gene expression of neuropeptides related to hypothalamic-pituitary-adrenocortical (HPA) axis activity and 2) to test the hypothesis that wheel running as a combined model of addictive behavior and stress exposure is associated with modulation of ionotropic glutamate receptor subunits in the ventral tegmental area. Voluntary running for three weeks but not for one night resulted in a rise in plasma corticosterone and adrenocorticotropic hormone (ACTH) levels (p<0.05) compared to those in control rats. Principal component analysis revealed the relation between POMC gene expression in the intermediate pituitary and running rate. Acute exposure of animals to voluntary wheel running induced a significant decrease in alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionate (AMPA) receptor GluR1 subunit mRNA levels (p<0.01), while repeated voluntary physical activity increased levels of GluR1 mRNA in the ventral tegmentum (p<0.05). Neither acute nor chronic wheel running influenced N-methyl-D-aspartate (NMDA) receptor subunit NR1 mRNA levels in the ventral tegmental area. Thus, the present study revealed changes in AMPA receptor subunit gene expression in a reward-related brain structure as well as an activation of HPA axis in response to compulsive wheel running in Lewis rats. It may be suggested that hormones of HPA axis and glutamate receptors belong to the factors that substantiate higher vulnerability to addictive behavior.

Involvement of glutamate neurotransmission in the development of excessive wheel running in Lewis rats.

Physical activities such as long-distance running can form a habit and might be related to drug-induced addictive behaviors. We investigated possible modulations of N-methyl-D-aspartate (NMDA) receptor subunits during voluntary wheel running in brain regions implicated in reward and addiction. It was observed that Lewis rats progressively increased their amount of daily running, reaching maximum levels of 4-6 km/day. After 3 weeks of running, mRNA levels coding for NR2A and NR2B subunits were increased in the ventral tegmental area, while only NR2A mRNA levels were found to be elevated in the frontal cortex. Long-term wheel running was also associated with increased binding of specific NMDA receptor antagonist [3H]CGP39653 in the frontal cortex. Moreover, pharmacological inhibition of glutamate release by repeated administration of phenytoin (20 mg/kg IP for 21 days) significantly suppressed daily running. These results suggest that glutamatergic neurotransmission might be related to neurobiological mechanisms underlying the compulsive character of voluntary wheel running.

Enriched environment influences brain-derived neurotrophic factor levels in rat forebrain after focal stroke.

Tissue levels of brain-derived neurotrophic factor (BDNF) protein were studied using enzyme immunoassay in different forebrain regions in the ipsi- and contralateral hemispheres of rats housed under enriched or standard conditions after the middle cerebral artery ligation. BDNF levels in the ipsilateral to ligation side was significantly higher only in the frontal cortex of standard as compared to enriched rats. However, BDNF overall was more abundant in standard than in enriched group. In addition, BDNF levels detected in the hippocampus and frontal cortex on the ischemic side of standard rats was higher as compared to contralateral side. The present study shows that housing conditions after permanent middle cerebral artery ligation leads to differential regulation of BDNF protein levels in forebrain regions which might have important implication for post-ischemic recovery.

Neuroprotective and behavioral efficacy of nerve growth factor-transfected hippocampal progenitor cell transplants after experimental traumatic brain injury.

OBJECT: Immortalized neural progenitor cells derived from embryonic rat hippocampus (HiB5), were transduced ex vivo with the gene for mouse nerve growth factor (NGF) to secrete NGF (NGF-HiB5) at 2 ng/hr/10(5) cells in culture. METHODS: Fifty-nine male Wistar rats weighing 300 to 370 g each were anesthetized with 60 mg/kg sodium pentobarbital and subjected to lateral fluid-percussion brain injury of moderate severity (2.3-2.4 atm, 34 rats) or sham injury (25 rats). At 24 hours postinjury, 2 microl (150,000 cells/microl) of [3H]thymidine-labeled NGF-HiB5 cells were transplanted stereotactically into three individual sites in the cerebral cortex adjacent to the injury site (14 rats). Separate groups of brain-injured rats received nontransfected (naive [n])-HiB5 cells (12 animals) or cell suspension vehicle (eight animals). One week postinjury, animals underwent neurological evaluation for motor function and cognition (Morris water maze) and were killed for histological, autoradiographic, and immunocytochemical analysis. Viable HiB5 cell grafts were identified in all animals, together with reactive microglia and macrophages located throughout the periinjured parenchyma and grafts (OX-42 immunohistochemistry). Brain-injured animals transplanted with either NGF-HiB5 or n-HiB5 cells displayed significantly improved neuromotor function (p < 0.05) and spatial learning behavior (p < 0.005) compared with brain-injured animals receiving microinjections of vehicle alone. A significant reduction in hippocampal CA3 cell death was observed in brain-injured animals receiving transplants of NGF-HiB5 cells compared with those receiving n-HiB5 cells or vehicle (p < 0.025). CONCLUSIONS: This study demonstrates that immortalized neural stem cells that have been retrovirally transduced to produce NGF can markedly improve cognitive and neuromotor function and rescue hippocampal CA3 neurons when transplanted into the injured brain during the acute posttraumatic period.

Gender and strain influence on neurogenesis in dentate gyrus of young rats.

To investigate whether rat hippocampal neurogenesis varies with strain and gender, the authors examined proliferating progenitor cells and their progeny in young male and female Sprague-Dawley (SD) and spontaneously hypertensive rats (SHR) using the thymidine analog bromodeoxyuridine (BrdU) combined with immunohistochemistry for the neuronal marker Calbindin D28k and glial fibrillary acidic protein. Rats were given 7 consecutive daily BrdU injections and were killed 1 day or 4 weeks later to allow for discrimination between proliferation and cell survival. Stereologic analysis of the numbers of BrdU-immunoreactive cells in the dentate gyrus revealed both a strain difference with significantly higher cell proliferation and net neurogenesis in SHR than in SD and a gender difference with males from both strains producing significantly more cells than their female counterparts. Whereas the number of progenitors four weeks after BrdU injections was still significantly greater in male than in female SHRs, resulting in a greater net neurogenesis in the male, the number of BrdU-immunoreactive cells did not differ between male and female SD rats, suggesting a greater survival of newly generated cells in the dentate gyrus in female than in male SD rats. No sex or strain difference was observed in the relative ratio of neurogenesis and gliogenesis.

Acupuncture and transcutaneous nerve stimulation in stroke rehabilitation: a randomized, controlled trial.

BACKGROUND AND PURPOSE: In small trials with control groups that receive no intervention, acupuncture has been reported to improve functional outcome after stroke. We studied effects of acupuncture and transcutaneous electrical nerve stimulation on functional outcome and quality of life after stroke versus a control group that received subliminal electrostimulation. METHODS: In a multicenter randomized controlled trial involving 7 university and district hospitals in Sweden, 150 patients with moderate or severe functional impairment were included. At days 5 to 10 after acute stroke, patients were randomized to 1 of 3 intervention groups: (a) acupuncture, including electroacupuncture; (b) sensory stimulation with high-intensity, low-frequency transcutaneous electrical nerve stimulation that induces muscle contractions; and (c) low-intensity (subliminal) high-frequency electrostimulation (control group). A total of 20 treatment sessions were performed over a 10-week period. Outcome variables included motor function, activities of daily living function, walking ability, social activities, and life satisfaction at 3-month and 1-year follow-up. RESULTS: At baseline, patients in each group were closely similar in all important prognostic variables. At 3-month and 1-year follow-ups, no clinically important or statistically significant differences were observed between groups for any of the outcome variables. The 3 treatment modalities were all conducted without major adverse effects. CONCLUSIONS: When compared with a control group that received subliminal electrostimulation, treatment during the subacute phase of stroke with acupuncture or transcutaneous electrical nerve stimulation with muscle contractions had no beneficial effects on functional outcome or life satisfaction.

Neuronal and fibre organization in neocortical grafts placed in post-ischaemic adult rat brain: a three-dimensional confocal microscopy study.

The dendritic morphology in neocortical grafts was studied with three-dimensional confocal laser scanning microscopy after microinjection of Lucifer Yellow into individual cells. The grafts had been implanted into infarct cavities in the neocortex of hypertensive rats 46 weeks earlier. The carbocyanine dye method was used to identify afferent (host to transplant) and efferent (transplant to host) connections. Pyramidal, nonpyramidal and glial cells were present in the transplants. Some dendrites had an almost normal appearance, but abnormalities (atypical orientation of apical, basal or oblique apical dendrites) were observed. Some bi-apical pyramidal neurons and pyramidal neurons with obliquely oriented apical dendrites were also observed. Carbocyanine dye-labelled fibres of different diameter formed a dense network in the transplant, enabling the border between transplant and host tissue to be clearly recognized. No labelled fibres were observed to enter the host brain. Fibres with "boutons en passant" and no preferential orientation were noted. It is proposed that Lucifer Yellow microinjection may be a useful method in studies aimed at improving graft morphology. Failure to demonstrate host to transplant connections with the carbocyanine dye method was contrary to earlier studies in which tracers were applied in vivo. A combined use of in-vivo and post-mortem tracer techniques is needed to establish the reason for the discrepancy.

Expression of zinc-positive cells and terminals in fetal neocortical homografts to adult rat depends on lesion type and rearing conditions.

Zinc-positive neurons and terminals, known to be associated with the glutamatergic projections in the brain, can be demonstrated by the histochemical Timm method and later modifications thereof. The adult rat neocortex contain a uniform lamination of zinc-positive cells with specific projections to, e.g., the striatum. We have previously reported that fetal neocortical grafts implanted in the adult rat neocortex combined with rearing in an enriched environment can improve behavioral functions and reduce the secondary atrophy of thalamus after cortex infarction in adult rats. In order to examine whether the expression of zinc positivity is ontogenetically inherent to neocortical neurons we grafted fetal neocortical tissue to aspiration or ischemic lesions of the frontoparietal neocortex of adult rats, followed by histochemical visualization of the vesicular zinc pool by selenite or sulfide. One further aim of the study was to elucidate to what extent the distribution of zinc-containing neurons and terminals in the grafts depended on rearing under different environmental conditions. The foremost finding of the present study was that the overall density of zinc-containing terminals in fetal cortical transplants placed in brain infarcts of adult spontaneously hypertensive rats is higher when the rats are reared in an enriched environment. Moreover, the presence and expression of zinc-positive neurons and terminals do not seem to be ontogenetically inherent to the cortical neurons as the fetal neocortical grafts placed in aspiration lesions contained no zinc-selenide-positive neurons and few or no zinc-selenide-positive terminals. The presence or expression of zinc-positive cells may thus be induced by ingrowth of fibers and terminals from the host brain as transplants placed in the ischemic lesions expressed both zinc-positive neurons and terminals.

The rotating pole test: evaluation of its effectiveness in assessing functional motor deficits following experimental head injury in the rat.

Neurological motor dysfunction is often an integral component of the neurological sequelae of traumatic brain injury (TBI). In experimental TBI, neurological motor testing is an outcome measure used to monitor severity of injury, and the response to treatment. This study evaluates the effectiveness and sensitivity of the rotating pole test (RP) to characterize and evaluate the temporal course of motor deficits after lateral fluid percussion (FP) injury to the rat brain. The results are compared with the previously characterized and widely used composite neuroscore of motor function (NS). The animals were required to walk across an elevated wooden pole that was either stationary or rotating to left or right directions at different speeds. Male Wistar rats underwent lateral FP injury of moderate severity (mean 2.4 atm, n = 9) or sham surgery (n = 9), and were tested at 48 h and 7 days post-injury using the NS and RP. The results of the NS directly correlated to the results of the RP, showing a significant injury effect at both 48 h and 7 days. This is the first study to show that the RP-test detects neurological motor deficits after lateral FP injury, and suggests that this technique is a reliable behavioral tool for evaluating neurological motor function in the acute period after experimental TBI.

Environmental influence on brain-derived neurotrophic factor messenger RNA expression after middle cerebral artery occlusion in spontaneously hypertensive rats.

Enriched environment significantly enhances postischemic functional outcome. We have tested the hypothesis that housing in enriched environment stimulates gene expression for brain-derived neurotrophic factor. After ligation of the middle cerebral artery in male spontaneously hypertensive rats, they were housed in individual cages for 30h, then housed either in standard cages or in an enriched environment. The rats were killed two to 30days after the ischemic event. Cryostat coronal sections through the dorsal hippocampus (Bregma -3.3) were processed for in situ hybridization using a rat-brain-derived neurotrophic factor messenger RNA antisense oligonucleotide probe. Postischemic gene expression was significantly higher in standard rats than in enriched rats in contralateral and peri-infarct cortex and in most parts of the hippocampus two, three and 12days after the ischemic event, with a trend for higher-than-baseline levels in standard rats and lower-than-baseline levels in enriched rats. At 20 and 30days the values for both groups were below baseline levels. Contrary to our hypothesis, gene expression in rats postoperatively housed in enriched environment was significantly lower than in standard rats at a time when other studies have reported hyperexcitability in the ipsilateral and contralateral cortex. Should the low messenger RNA levels correspond to low protein synthesis, this might indicate that dampening of the early postischemic hyperexcitability may be beneficial. Low levels in both groups at 20 and 30days may correspond to loss of callosal connections in the opposite hemisphere and to horizontal cortical connections in the lesioned hemisphere.

[The brain is shaped by stimulation and challenge]. / Hjärnan formas av stimulans och utmaningar.

The healthy adult brain retains a certain capacity for plasticity and functional reorganization throughout the life span. Morphologic, neuropsychological and neuroimaging studies have demonstrated that neuronal connections and cortical maps can be remodeled by our experience and activities. Activity-induced increase in neuronal connections may to some extent compensate for neuronal loss during aging. Increased knowledge of the potential capability of the adult brain to compensate for brain lesions is likely to improve rehabilitation strategies.

Brain plasticity and stroke rehabilitation. The Willis lecture.

Neuronal connections and cortical maps are continuously remodeled by our experience. Knowledge of the potential capabilityof the brain to compensate for lesions is a prerequisite for optimal stroke rehabilitation strategies. Experimental focal cortical lesions induce changes in adjacent cortex and in the contralateral hemisphere. Neuroimaging studies in stroke patients indicate altered poststroke activation patterns, which suggest some functional reorganization. To what extent functional imaging data correspond to outcome data needs to be evaluated. Reorganization may be the principle process responsible for recovery of function after stroke, but what are the limits, and to what extent can postischemic intervention facilitate such changes? Postoperative housing of animals in an enriched environment can significantly enhance functional outcome and can also interact with other interventions, including neocortical grafting. What role will neuronal progenitor cells play in future rehabilitation-stimulated in situ or as neural replacement? And what is the future for blocking neural growth inhibitory factors? Better knowledge of postischemic molecular and neurophysiological events, and close interaction between basic and applied research, will hopefully enable us to design rehabilitation strategies based on neurobiological principles in a not-too-distant future.

Environmental influence on gene expression and recovery from cerebral ischemia.

An emerging concept in neurobiology is that the adult brain retains a capacity for plasticity and functional reorganization throughout the life span. Experimental data from electrophysiological, morphological and behavioral studies have documented experience dependent plasticity in the intact and injured adult brain. Neuroimaging clinical studies indicate altered post stroke functional activation patterns, usually including activation of the intact hemisphere. However, there is some disagreement regarding their functional significance and longitudinal studies correlating outcome and activation pattern are needed to solve some controversies. Postoperative housing of rats in activity stimulating environment after ligation of the middle cerebral artery significantly enhances outcome. Gene expression for brain derived neurotrophic factor and Ca2+/calmodulin-dependent protein kinase II, two substances with potential role in brain plasticity, show different patterns in animals housed in standard and in enriched environment. The functional significance of altered gene expression needs to be evaluated.