Correlation between neonatal calf diarrhea and the level of maternally derived antibodies.

Passively acquired antibodies through colostrum will protect calves against etiological agents of neonatal calf diarrhea. Among them enteric diseases due to strains of Enterotoxigenic Escherichia coli (ETEC) are the most commonly occurring form of colibacillosis in newborn calves. Specific antibodies against whole ETEC cells and total immunoglobulin G in dam serum, colostrum and calf serum were determined. There were significant differences (P=0.0005) between antibody titers in normal and diarrheic groups, in which diarrheic group had a higher titer. Total IgG concentration in diarrheic calves (20.86 ± 0.49), their dams (23.48 ± 0.54) and colostrum (33.40 ± 0.50) was less than normal group (P=0.0005). There was a highly significant positive correlation between dam total IgG with calf total IgG (r=0.022; ratio=52.11). Colostral anti-E. coli antibody had a highly significant positive correlation with anti-E. coli in calf serum (r=0.345; ratio=0.62). Anti-E. coli antibody in calf serum had a highly significant negative correlati with total IgG of dam serum, colostrum and calf serum. While the level of anti-E. coli antibodies in diarrheic group was considerably higher than normal group, our findings reported here are in agreement that immunity to diarrhea also might be correlated with maternal cells or cellular components as well as cytokines which are transferred by colostrum to neonatal calves. Nevertheless, the level of maternally derived antibodies is a promising indicator for passive immunity and protection against diarrhea in neonatal calves.

Reinforcement learning of self-regulated sensorimotor ß-oscillations improves motor performance.

Self-regulation of sensorimotor oscillations is currently researched in neurorehabilitation, e.g. for priming subsequent physiotherapy in stroke patients, and may be modulated by neurofeedback or transcranial brain stimulation. It has still to be demonstrated, however, whether and under which training conditions such brain self-regulation could also result in motor gains. Thirty-two right-handed, healthy subjects participated in a three-day intervention during which they performed 462 trials of kinesthetic motor-imagery while a brain-robot interface (BRI) turned event-related ß-band desynchronization of the left sensorimotor cortex into the opening of the right hand by a robotic orthosis. Different training conditions were compared in a parallel-group design: (i) adaptive classifier thresholding and contingent feedback, (ii) adaptive classifier thresholding and non-contingent feedback, (iii) non-adaptive classifier thresholding and contingent feedback, and (iv) non-adaptive classifier thresholding and non-contingent feedback. We studied the task-related cortical physiology with electroencephalography and the behavioral performance in a subsequent isometric motor task. Contingent neurofeedback and adaptive classifier thresholding were critical for learning brain self-regulation which, in turn, led to behavioral gains after the intervention. The acquired skill for sustained sensorimotor ß-desynchronization correlated significantly with subsequent motor improvement. Operant learning of brain self-regulation with a BRI may offer a therapeutic perspective for severely affected stroke patients lacking residual hand function.

Decoding of motor intentions from epidural ECoG recordings in severely paralyzed chronic stroke patients.

OBJECTIVE: Recently, there have been several approaches to utilize a brain-computer interface (BCI) for rehabilitation with stroke patients or as an assistive device for the paralyzed. In this study we investigated whether up to seven different hand movement intentions can be decoded from epidural electrocorticography (ECoG) in chronic stroke patients. APPROACH: In a screening session we recorded epidural ECoG data over the ipsilesional motor cortex from four chronic stroke patients who had no residual hand movement. Data was analyzed offline using a support vector machine (SVM) to decode different movement intentions. MAIN RESULTS: We showed that up to seven hand movement intentions can be decoded with an average accuracy of 61% (chance level 15.6%). When reducing the number of classes, average accuracies up to 88% can be achieved for decoding three different movement intentions. SIGNIFICANCE: The findings suggest that ipsilesional epidural ECoG can be used as a viable control signal for BCI-driven neuroprosthesis. Although patients showed no sign of residual hand movement, brain activity at the ipsilesional motor cortex still shows enough intention-related activity to decode different movement intentions with sufficient accuracy.

Neurostimulation for Parkinson's disease with early motor complications.

BACKGROUND: Subthalamic stimulation reduces motor disability and improves quality of life in patients with advanced Parkinson's disease who have severe levodopa-induced motor complications. We hypothesized that neurostimulation would be beneficial at an earlier stage of Parkinson's disease. METHODS: In this 2-year trial, we randomly assigned 251 patients with Parkinson's disease and early motor complications (mean age, 52 years; mean duration of disease, 7.5 years) to undergo neurostimulation plus medical therapy or medical therapy alone. The primary end point was quality of life, as assessed with the use of the Parkinson's Disease Questionnaire (PDQ-39) summary index (with scores ranging from 0 to 100 and higher scores indicating worse function). Major secondary outcomes included parkinsonian motor disability, activities of daily living, levodopa-induced motor complications (as assessed with the use of the Unified Parkinson's Disease Rating Scale, parts III, II, and IV, respectively), and time with good mobility and no dyskinesia. RESULTS: For the primary outcome of quality of life, the mean score for the neurostimulation group improved by 7.8 points, and that for the medical-therapy group worsened by 0.2 points (between-group difference in mean change from baseline to 2 years, 8.0 points; P=0.002). Neurostimulation was superior to medical therapy with respect to motor disability (P<0.001), activities of daily living (P<0.001), levodopa-induced motor complications (P<0.001), and time with good mobility and no dyskinesia (P=0.01). Serious adverse events occurred in 54.8% of the patients in the neurostimulation group and in 44.1% of those in the medical-therapy group. Serious adverse events related to surgical implantation or the neurostimulation device occurred in 17.7% of patients. An expert panel confirmed that medical therapy was consistent with practice guidelines for 96.8% of the patients in the neurostimulation group and for 94.5% of those in the medical-therapy group. CONCLUSIONS: Subthalamic stimulation was superior to medical therapy in patients with Parkinson's disease and early motor complications. (Funded by the German Ministry of Research and others; EARLYSTIM ClinicalTrials.gov number, NCT00354133.).

Increased coherence among striatal regions in the theta range during attentive wakefulness

The striatum, the largest component of the basal ganglia, is usually subdivided into associative, motor and limbic components. However, the electrophysiological interactions between these three subsystems during behavior remain largely unknown. We hypothesized that the striatum might be particularly active during exploratory behavior, which is presumably associated with increased attention. We investigated the modulation of local field potentials (LFPs) in the striatum during attentive wakefulness in freely moving rats. To this end, we implanted microelectrodes into different parts of the striatum of Wistar rats, as well as into the motor, associative and limbic cortices. We then used electromyograms to identify motor activity and analyzed the instantaneous frequency, power spectra and partial directed coherence during exploratory behavior. We observed fine modulation in the theta frequency range of striatal LFPs in 92.5 ± 2.5% of all epochs of exploratory behavior. Concomitantly, the theta power spectrum increased in all striatal channels (P < 0.001), and coherence analysis revealed strong connectivity (coefficients >0.7) between the primary motor cortex and the rostral part of the caudatoputamen nucleus, as well as among all striatal channels (P < 0.001). Conclusively, we observed a pattern of strong theta band activation in the entire striatum during attentive wakefulness, as well as a strong coherence between the motor cortex and the entire striatum. We suggest that this activation reflects the integration of motor, cognitive and limbic systems during attentive wakefulness.

Increased coherence among striatal regions in the theta range during attentive wakefulness.

The striatum, the largest component of the basal ganglia, is usually subdivided into associative, motor and limbic components. However, the electrophysiological interactions between these three subsystems during behavior remain largely unknown. We hypothesized that the striatum might be particularly active during exploratory behavior, which is presumably associated with increased attention. We investigated the modulation of local field potentials (LFPs) in the striatum during attentive wakefulness in freely moving rats. To this end, we implanted microelectrodes into different parts of the striatum of Wistar rats, as well as into the motor, associative and limbic cortices. We then used electromyograms to identify motor activity and analyzed the instantaneous frequency, power spectra and partial directed coherence during exploratory behavior. We observed fine modulation in the theta frequency range of striatal LFPs in 92.5 ± 2.5% of all epochs of exploratory behavior. Concomitantly, the theta power spectrum increased in all striatal channels (P < 0.001), and coherence analysis revealed strong connectivity (coefficients >0.7) between the primary motor cortex and the rostral part of the caudatoputamen nucleus, as well as among all striatal channels (P < 0.001). Conclusively, we observed a pattern of strong theta band activation in the entire striatum during attentive wakefulness, as well as a strong coherence between the motor cortex and the entire striatum. We suggest that this activation reflects the integration of motor, cognitive and limbic systems during attentive wakefulness.

Histopathological features of the brain, liver, kidney and spleen following an innovative polytrauma model of the mouse.

OBJECT: Among the various introduced experimental traumatic brain injury models, there is a clear paucity of proper experimental polytrauma models. To overcome this experimental gap we introduced such a polytrauma model in the mouse including traumatic brain injury. Here, we report on the histopathological features of the brain, lung, kidney, spleen and liver. MATERIALS AND METHODS: 20 male C57BL mice with a mean weight of 23 g were anesthetized with ketamine and xylazine. The anaesthetized animals were subjected to a controlled cortical impact (CCI) over the left parieto-temporal cortex using rounded-tip impounder for application of a standardized brain injury. Following fracture of the right femur using a guillotine, a volume-controlled hemorrhagic shock was induced. The control groups included animals with CCI only (n=20) and animals with femur fracture plus hemorrhagic shock without CCI (n=20). Subjects were sacrified at 96 h following trauma. Brain, lung, kidney, spleen and liver of the animals underwent histopathological examinations. RESULTS: The mortality rate at 96 h was 25% in the polytrauma group versus 10% in the control groups. Within the histopathological investigations, polytraumatized animals differ from those with a single trauma (traumatic brain injury or femur fracture with hemorrhagic shock) with various severity. CONCLUSION: The findings of this study show that such a polytrauma model can be standardized resulting in a reproducible damage. This model fulfills the requirements of a standardized animal model. It allows adequate analogies and inferences to the clinical situation of a polytrauma in humans.

Hematologic and Clinical Aspects of Experimental Ovine Anaplasmosis Caused by Anaplasma ovis in Iran.

BACKGROUND: Anaplasma ovis infections can cause clinical symptoms in acute phase and lead to huge economic losses in flocks. The aim of the present study was to investigate the hematological and parasitological changes in experimental anaplasmosis in sheep with Iranian strain of A. ovis. METHOD: Five male sheep without any blood parasite infection were selected. One hundred ml heparinized blood was collected from splenectomised sheep that showed 6% A. ovis parasitemia. Inoculums of 20 ml blood were administered intravenously to each test animal. Hematological, parasitological and clinical changes of experimental anaplasmosis were studied in 0-38 days post infection. RESULT: Parasitemia was detected 3 days post infection and reached its maximum level on the day 12 of experiment in test animals. Then the parasitemia was declined, but the organism could be found persistently until the last day of study. The red cell counts, packed cell volume and hemoglobin concentration were decreased and mean corpuscular volume was increased significantly during the infection period. Reticulocytosis and basophilic stippling were also detected. No significant changes were observed in total and differential leukocyte count and animal body temperature. CONCLUSION: Experimental A. ovis infection in sheep resulted in marked normocytic normochromic anemia at the beginning of the infection which became macrocytic normochromic by the development of the disease. There were negative correlations between parasitemia and RBC, PCV and Hb values, therefore hematological assessment can be considered as a practical diagnostic tool in ovine anaplasmosis.

Closing the sensorimotor loop: haptic feedback facilitates decoding of motor imagery.

The combination of brain-computer interfaces (BCIs) with robot-assisted physical therapy constitutes a promising approach to neurorehabilitation of patients with severe hemiparetic syndromes caused by cerebrovascular brain damage (e.g. stroke) and other neurological conditions. In such a scenario, a key aspect is how to reestablish the disrupted sensorimotor feedback loop. However, to date it is an open question how artificially closing the sensorimotor feedback loop influences the decoding performance of a BCI. In this paper, we answer this issue by studying six healthy subjects and two stroke patients. We present empirical evidence that haptic feedback, provided by a seven degrees of freedom robotic arm, facilitates online decoding of arm movement intention. The results support the feasibility of future rehabilitative treatments based on the combination of robot-assisted physical therapy with BCIs.

Transition from the locked in to the completely locked-in state: a physiological analysis.

OBJECTIVE: To clarify the physiological and behavioral boundaries between locked-in (LIS) and the completely locked-in state (CLIS) (no voluntary eye movements, no communication possible) through electrophysiological data and to secure brain-computer-interface (BCI) communication. METHODS: Electromyography from facial muscles, external anal sphincter (EAS), electrooculography and electrocorticographic data during different psychophysiological tests were acquired to define electrophysiological differences in an amyotrophic lateral sclerosis (ALS) patient with an intracranially implanted grid of 112 electrodes for nine months while the patient passed from the LIS to the CLIS. RESULTS: At the very end of the LIS there was no facial muscle activity, nor external anal sphincter but eye control. Eye movements were slow and lasted for short periods only. During CLIS event related brain potentials (ERP) to passive limb movements and auditory stimuli were recorded, vibrotactile stimulation of different body parts resulted in no ERP response. CONCLUSIONS: The results presented contradict the commonly accepted assumption that the EAS is the last remaining muscle under voluntary control and demonstrate complete loss of eye movements in CLIS. The eye muscle was shown to be the last muscle group under voluntary control. The findings suggest ALS as a multisystem disorder, even affecting afferent sensory pathways. SIGNIFICANCE: Auditory and proprioceptive brain-computer-interface (BCI) systems are the only remaining communication channels in CLIS.

Towards brain-robot interfaces in stroke rehabilitation.

A neurorehabilitation approach that combines robot-assisted active physical therapy and Brain-Computer Interfaces (BCIs) may provide an additional mileage with respect to traditional rehabilitation methods for patients with severe motor impairment due to cerebrovascular brain damage (e.g., stroke) and other neurological conditions. In this paper, we describe the design and modes of operation of a robot-based rehabilitation framework that enables artificial support of the sensorimotor feedback loop. The aim is to increase cortical plasticity by means of Hebbian-type learning rules. A BCI-based shared-control strategy is used to drive a Barret WAM 7-degree-of-freedom arm that guides a subject's arm. Experimental validation of our setup is carried out both with healthy subjects and stroke patients. We review the empirical results which we have obtained to date, and argue that they support the feasibility of future rehabilitative treatments employing this novel approach.

Novel cell nucleus directed fluorescent tetraazacyclododecane-tetra-acetic acid compounds.

Peptide conjugates derived from the SV 40 T antigen nuclear localisation sequence (NLS) have been successfully used to translocate both fluorescein isothiocyanate (FITC) and Gadolinium (Gd)-1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) into the cytoplasm and nucleus of glioma cells. However, uptake occurred only in up to 35% of cells. To improve cellular uptake, we designed three novel FITC-labelled Gd-DOTA conjugates. In the first conjugate, the commonly used Gd-DOTA-complex was coupled to the nuclear localization sequence (NLS) of the Simian Virus (SV) 40 T antigen alone as a control. In the second conjugate, the Gd-DOTA-coupled SV 40 T antigen NLS was elongated by the HIV-1 tat peptide (HIV-NLS). A third conjugate, in which the Gd-DOTA-complex was coupled to the SV 40 T antigen NLS elongated by a peptide containing seven arginines and six aminohexanoic acids (Ahx6R7) was also synthesized (AHX-NLS). By means of confocal laser scanning microscopy, fluorescence activated cell sorting, magnetic resonance imaging (MRI) and viability tests we were able to demonstrate that the first conjugate containing only the NLS of the SV 40 T antigen stained the nuclei of no more than 10-12% of U373 and LN18 glioma cells, resulting in low signal intensity in MRI. The stained cells remained viable. After incubation with conjugates HIV-NLS and AHX-NLS the nuclei of up to 73% of U373 and LN18 glioma cells were stained. This was associated with high signal intensity in MRI and cell death. As previously shown, the gadolinium ion reduces cellular uptake of DOTA conjugates. To confirm this, the conjugates were produced with or without gadolinium. The gadolinium-free DOTA conjugates showed a higher cellular uptake rate and an increased cytotoxic potential.

The retrosigmoid intradural suprameatal approach to posterior cavernous sinus: microsurgical anatomy.

OBJECTIVE: The retrosigmoid intradural suprameatal approach includes the standard retrosigmoid suboccipital route with drilling of the petrous bone above and anterior of the internal auditory meatus, allowing for exposure of the trigeminal nerve within the Meckel's cave and of the middle fossa. In this study, the authors analyzed the potential use of an extended variation of the suprameatal route to approach the posterior cavernous sinus for microsurgery of, e.g., petroclival meningiomas and trigeminal schwannomas. METHODS: The microsurgical anatomy of the retrosigmoid suprameatal approach was examined by using 10 adult cadaveric specimens (20 sides), using 3-40x magnification. The exposure to the posterior cavernous sinus provided by this approach was focused. RESULTS: After drilling the suprameatal tubercle toward the petrous apex, the Meckel's cave was exposed. The trochlear nerve was the landmark for opening the cavernous sinus by this approach. The dura located medially to the entry point of the trochlear nerve into the tentorium was resected, allowing exposure of the intracavernous carotid artery with its meningohypophyseal trunk. CONCLUSION: The extended retrosigmoid intradural suprameatal approach allows exposure of the posterior cavernous sinus and may be used to remove lesions of the posterior fossa extending into the Meckel's cave and into the cavernous sinus.

Venous complications following petrosal vein sectioning in surgery of petrous apex meningiomas.

OBJECTIVE: Meningiomas involving the petrous apex regularly show a close relationship with the superior petrosal vein which is sometimes obliterated during surgery due to its proximity to the tumour. However, there is no study available so far focusing on the frequency of postoperative venous congestion related complications following petrosal vein obliteration as well as on pre- and intraoperative findings related to them. METHODS: Fifty-nine patients with meningiomas involving the petrous apex were analyzed concerning the intraoperative preservation or sacrifice of the petrosal vein and postoperative complications related to venous occlusion. RESULTS: When a petrosal vein was occluded, in 9 of 30 cases venous-related complications occurred with a minor venous-congestion phenomenon in seven cases and major complications in two cases. When the petrosal vein complex was preserved, there were no similar complications. CONCLUSION: Preservation of the petrosal venous complex, especially of large caliber veins, should be attempted whenever possible to increase the safety of surgery. In cases of petrosal vein obliteration, effective brainstem decompression following tumour removal is essential to minimizing the risk of cerebellar congestion.

Cellular uptake of cationic gadolinium-DOTA peptide conjugates with and without N-terminal myristoylation.

Cellular and nuclear uptake of dual labelled conjugates could be of great value for chemotherapy and cancer diagnostics. Therefore we designed conjugates in which gadolinium (Gd)-1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA), a contrast agent for magnetic resonance imaging and fluorescein isothiocyanate (FITC), a fluorescence marker were coupled to membrane translocation sequences (MTS). The MTSs we employed were the third helix of the Antennapedia homeodomain, the HIV-1 Tat peptide and the N-myristoylated HIV-1 Tat peptide. We used confocal laser scanning microscopy, fluorescence activated cell sorting, magnetic resonance imaging (MRI) and viability tests to examine the cellular and nuclear uptake of these conjugates into U373 glioma cells, as well as their cytotoxic effects. We found that the Antennapedia conjugate was taken up by no more than 20% of the cells. The HIV-1 Tat conjugate showed even lower uptake into less than 3% of cells. Interestingly, N-myristoylation of the HIV-1 Tat conjugate drastically improved its cellular uptake. Up to 70% of cells showed cellular and nuclear uptake of the N-myristoylated HIV-1 Tat conjugate. Conjugate cytotoxicity appears to correlate with cellular uptake.

A novel polyarginine containing Smac peptide conjugate that mediates cell death in tumor and healthy cells.

The seven N-terminal amino acids AVPIAQK (SmacN7) of the mitochondrial protein Smac (second mitochondria-derived activator of caspase) promote caspase activation by binding specifically to inhibitor of apoptosis proteins (IAPs) and blocking their inhibitory activity. SmacN7 cannot pass through the cell membrane, but to be of therapeutic use it would be essential for it to enter the cell. To achieve transmembrane transport of SmacN7 we coupled it to a novel fluorescein isothiocyanate (FITC)-labelled transmembrane transport peptide RRRRK(FITC)RRRR via ss-alanine to produce the conjugate AVPIAQKssA RRRRK(FITC)RRRR. Because IAPs are much more strongly expressed in the cytoplasm of tumor cells, we expected this conjugate to produce staining of the cytoplasm, and for this to be stronger in tumor cells than in healthy cells. Surprisingly, we found strong nuclear uptake of the Smac conjugate and of the transport peptide alone without subsequent release in both tumor cells and healthy cells from the bladder, prostate, and brain. This was accompanied by cell death. In contrast to expectations, it appears that the apoptotic effects observed do not result from the SmacN7 cargo alone.

Novel dual labelled nucleus-directed conjugates containing correct and mutant nuclear localisation sequences.

Gadolinium (Gd)-1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) is commonly used as contrast agent in magnetic resonance imaging (MRI), but cannot enter the cytoplasm or cell nucleus. We designed a tetrapeptide carrying fluorescein isothiocyanate (FITC) and Gd-DOTA. This conjugate was coupled to the nuclear localisation sequence (NLS) of the Simian Virus (SV) 40 T antigen elongated by four arginines. In a second conjugate one lysine of the original SV 40 T antigen NLS was replaced by threonine. An FITC-labelled DOTA-tetrapeptide conjugate lacking the NLS peptide served as a negative control. We tried to achieve sequence specific entry of the Gd-DOTA-complex into the cytoplasm and nucleus of human U373 and LN18 glioma cells. Using confocal laser scanning microscopy (CLSM), fluorescence activated cell sorting (FACS), magnetic resonance imaging (MRI) and viability tests we found that both NLS conjugates stained the cell nuclei of U373 and LN18 glioma cells, represented also by a rise in signal intensity compared to the native control in MRI. The majority of stained cells remained viable. All conjugates were also produced without Gd. The Gd-free DOTA-conjugates showed an increase in cellular uptake rate. Conjugate cytotoxicity correlated closely to cellular uptake. Gd-containing DOTA-conjugates directed to the cytoplasm or the nucleus may be the basis for the development of novel diagnostic agents.