Chloride and lactate as prognostic indicators of calf diarrhea from eighty-nine cases.

Importance: Deaths due to neonatal calf diarrhea are still one of the most critical problems of cattle breeding worldwide. Determining the parameters that can predict diarrhea-related deaths in calves is especially important in terms of prognosis and treatment strategies for the disease.

Objective: The primary purpose of this study was to determine mortality rates and durations, survival status, and predictive prognosis parameters based on vital signs, hematology, and blood gas analyses in neonatal diarrheic calves.

Discharge and Role of GABA Pontomesencephalic Neurons in Cortical Activity and Sleep-Wake States Examined by Optogenetics and Juxtacellular Recordings in Mice.

The cholinergic neurons in the pontomesencephalic tegmentum have been shown to discharge in association with and promote cortical activation during active or attentive waking and paradoxical or rapid eye movement sleep. However, GABA neurons lie intermingled with the cholinergic neurons and may contribute to or oppose this activity and role. Here we investigated and the properties, activities, and role of GABA neurons within the laterodorsal tegmental and sublaterodorsal tegmental nuclei (LDT/SubLDT) using male and female transgenic mice expressing channelrhodopsin-()- in vesicular GABA transporter ()-expressing neurons.

Discharge and Role of Acetylcholine Pontomesencephalic Neurons in Cortical Activity and Sleep-Wake States Examined by Optogenetics and Juxtacellular Recording in Mice.

Acetylcholine (ACh) neurons in the pontomesencephalic tegmentum (PMT) are thought to play an important role in promoting cortical activation with waking (W) and paradoxical sleep [PS; or rapid eye movement (REM)], but have yet to be proven to do so by selective stimulation and simultaneous recording of identified ACh neurons. Here, we employed optogenetics combined with juxtacellular recording and labeling of neurons in transgenic (TG) mice expressing ChR2 in choline acetyltransferase (ChAT)-synthesizing neurons. We established then in anesthetized (A) and unanesthetized (UA), head-fixed mice that photostimulation elicited a spike with short latency in neurons which could be identified by immunohistochemical staining as ACh neurons within the laterodorsal (LDT)/sublaterodorsal (SubLDT) and pedunculopontine tegmental (PPT) nuclei.

Discharge profiles across the sleep-waking cycle of identified cholinergic, GABAergic, and glutamatergic neurons in the pontomesencephalic tegmentum of the rat.

Distributed within the laterodorsal tegmental and pedunculopontine tegmental nuclei (LDT and PPT), cholinergic neurons in the pontomesencephalic tegmentum have long been thought to play a critical role in stimulating cortical activation during waking (W) and paradoxical sleep (PS, also called REM sleep), yet also in promoting PS with muscle atonia. However, the discharge profile and thus precise roles of the cholinergic neurons have remained uncertain because they lie intermingled with GABAergic and glutamatergic neurons, which might also assume these roles. By applying juxtacellular recording and labeling in naturally sleeping-waking, head-fixed rats, we investigated the discharge profiles of histochemically identified cholinergic, GABAergic, and glutamatergic neurons in the LDT, SubLDT, and adjoining medial part of the PPT (MPPT) in relation to sleep-wake states, cortical activity, and muscle tone.

Oseltamivir reduces hippocampal abnormal EEG activities after a virus infection (influenza) in isoflurane-anesthetized rats.

Background: Oseltamivir phosphate (OP, Tamiflu(®)) is a widely used drug in the treatment of influenza with fever. However, case reports have associated OP intake with sudden abnormal behaviors. In rats infected by the influenza A virus (IAV), the electroencephalogram (EEG) displayed abnormal high-voltage amplitudes with spikes and theta oscillations at a core temperature of 39.

Influenza virus-cytokine-protease cycle in the pathogenesis of vascular hyperpermeability in severe influenza.

Background: Severe influenza is characterized by cytokine storm and multiorgan failure with edema. The aim of this study was to define the impact of the cytokine storm on the pathogenesis of vascular hyperpermeability in severe influenza.

Methods: Weanling mice were infected with influenza A WSN/33(H1N1) virus.

Mechanisms of matrix metalloproteinase-9 upregulation and tissue destruction in various organs in influenza A virus infection.

Severe influenza is characterized clinicopathologically by multiple organ failure, although the relationship amongst virus and host factors that influence this morbid outcome and the underlying mechanisms of action remain unclear. The present study identified marked upregulation of matrix metalloproteinase (MMP)-9 and pro-inflammatory cytokine tumor necrosis factor alpha (TNF-alpha) in various organs after intranasal infection of influenza A WSN virus. MMP-9 and TNF-alpha were upregulated in the lung, the site of initial infection, as well as in the brain and heart.

Cortical and thalamic components of neocortical kindling-induced epileptogenesis in behaving cats.

Kindling is an essential operating paradigm of the nervous system extensively used both as a model of epileptogenesis and neuroplasticity. In a parallel study conducted on chronically implanted non-anesthetized kindled cats, we report the occurrence of long-lasting slow oscillatory patterns (1.5-2 Hz) called outlasting activities (OA) following the acute seizures (AS) induced by cortical stimulation.

State-dependent slow outlasting activities following neocortical kindling in cats.

Some forms of electrographic seizures are generated at the level of the cortical network. Neocortical kindling exhibits a resistance to produce generalized convulsive seizures, and therefore, it was rather difficult to use it to study the cortical epileptogenesis. Here, using supra-threshold cortical kindling, we report electrophysiological patterns of field-potential synchronization and intracellular activities in chronically implanted non-anesthetized cats, during different states of vigilance, and during acute seizures elicited by prolonged (20-60 s) electrical stimulation.

EPSP depression following neocortical seizures in cat.

To study the possible mechanism(s) underlying unresponsiveness following neocortical seizures, we recorded excitatory postsynaptic potentials (EPSPs) of cortical neurons evoked by ipsilateral cortical stimulation before and after spontaneous or elicited seizures. Regular-spiking neurons (n = 32) were intracellularly recorded in association area five of cats under ketamine-xylazine or barbiturate anesthesia. Compared with control responses, cortically evoked EPSPs were characterized by decreased amplitude after electrographic seizures.

Waking-sleep modulation of paroxysmal activities induced by partial cortical deafferentation.

We investigated the dependency of electrical seizures produced by cortical undercut upon behavioral states of vigilance in chronically implanted cats. Experiments were performed 1-12 weeks after white matter transection. Multisite field potentials and intracellular activity were recorded from suprasylvian and marginal gyri.

Increased propensity to seizures after chronic cortical deafferentation in vivo.

Cortical injury may lead to clinical seizures. We investigated the changing patterns of the sleeplike slow oscillation and its tendency to develop into paroxysmal activity consisting of spike-wave (SW) complexes at 2-4 Hz after partial deafferentation of the suprasylvian gyrus. Experiments were carried out in anesthetized cats, at different time intervals (wk 1 to wk 5, W1-W5) after cortical undercut.

Synaptic plasticity in local cortical network in vivo and its modulation by the level of neuronal activity.

Neocortical neurons maintain high firing rates across all behavioral states of vigilance but the discharge patterns vary during different types of brain oscillations, which are assumed to play an important role in information processing and memory consolidation. In the present study, we report that trains of stimuli applied to local neocortical networks of cats, at frequencies that mimic endogenous brain rhythms, produced depression or potentiation of postsynaptic potentials, which lasted for several minutes. This form of synaptic plasticity was not mediated through NMDA receptors since it persisted after blockade of these receptors, but was strongly modulated by the level of background neuronal activity.

Synaptic enhancement induced through callosal pathways in cat association cortex.

The corpus callosum plays a major role in synchronizing neocortical activities in the two hemispheres. We investigated the changes in callosally elicited excitatory postsynaptic potentials (EPSPs) of neurons from cortical association areas 5 and 7 of cats under barbiturate or ketamine-xylazine anesthesia. Single pulses to callosal pathway evoked control EPSPs; pulse-trains were subsequently applied at different frequencies to homotopic sites in the contralateral cortex, as conditioning stimulation; thereafter, the single pulses were applied again to test changes in synaptic responsiveness by comparing the amplitudes of control and conditioned EPSPs.

Electrophysiological properties and input-output organization of callosal neurons in cat association cortex.

Intracellular recordings from association cortical areas 5 and 7 were performed in cats under barbiturate or ketamine-xylazine anesthesia to investigate the activities of different classes of neurons involved in callosal pathways, which were electrophysiologically characterized by depolarizing current steps. Excitatory postsynaptic potentials (EPSPs), inhibitory postsynaptic potentials (IPSPs), and/or antidromic responses were elicited by stimulating homotopic sites in the contralateral cortical areas. Differential features of EPSPs related to latencies, amplitudes, and slopes were detected in closely located (50 microm or less) neurons recorded in succession along the same electrode track.