On the mechanisms underlying the depolarization block in the spiking dynamics of CA1 pyramidal neurons.

Under sustained input current of increasing strength neurons eventually stop firing, entering a depolarization block. This is a robust effect that is not usually explored in experiments or explicitly implemented or tested in models. However, the range of current strength needed for a depolarization block could be easily reached with a random background activity of only a few hundred excitatory synapses.

Alteration of bacterial communities and organic matter in microbial fuel cells (MFCs) supplied with soil and organic fertilizer.

The alteration of the organic matter (OM) and the composition of bacterial community in microbial fuel cells (MFCs) supplied with soil (S) and a composted organic fertilizer (A) was examined at the beginning and at the end of 3 weeks of incubation under current-producing as well as no-current-producing conditions. Denaturing gradient gel electrophoresis revealed a significant alteration of the microbial community structure in MFCs generating electricity as compared with no-current-producing MFCs. The genetic diversity of cultivable bacterial communities was assessed by random amplified polymorphic DNA (RAPD) analysis of 106 bacterial isolates obtained by using both generic and elective media.

Differential effects of Kv7 (M-) channels on synaptic integration in distinct subcellular compartments of rat hippocampal pyramidal neurons.

The K(V)7/M-current is an important determinant of neuronal excitability and plays a critical role in modulating action potential firing. In this study, using a combination of electrophysiology and computational modelling, we show that these channels selectively influence peri-somatic but not dendritic post-synaptic excitatory synaptic potential (EPSP) integration in CA1 pyramidal cells. K(V)7/M-channels are highly concentrated in axons.

A multi-compartment model for interneurons in the dorsal lateral geniculate nucleus.

GABAergic interneurons (INs) in the dorsal lateral geniculate nucleus (dLGN) shape the information flow from retina to cortex, presumably by controlling the number of visually evoked spikes in geniculate thalamocortical (TC) neurons, and refining their receptive field. The INs exhibit a rich variety of firing patterns: Depolarizing current injections to the soma may induce tonic firing, periodic bursting or an initial burst followed by tonic spiking, sometimes with prominent spike-time adaptation. When released from hyperpolarization, some INs elicit rebound bursts, while others return more passively to the resting potential.

A new paradigm in health care curriculums: the pharmaceutical and health care business degree.

The rapid growth of the healthcare industry, and the need to operate more efficiently in this environment, has generated an unmet need for competent business professionals with knowledge of the health care sciences. Additionally, student demand for a business curriculum that would satisfy the needs of the health care industry has provided the impetus for the development of the B.S.

Redox regulation of cellular stress response in multiple sclerosis.

Multiple sclerosis (MS) is an autoimmune-mediated neurodegenerative disease with characteristic foci of inflammatory demyelination in the brain, spinal cord, and optic nerves. Recent studies have demonstrated not only that axonal damage and neuronal loss are significant pathologic components of MS, but that this neuronal damage is thought to cause the permanent neurologic disability often seen in MS patients. Emerging finding suggests that altered redox homeostasis and increased oxidative stress, primarily implicated in the pathogenesis of MS, are a trigger for activation of a brain stress response.

Post-thyroidectomy hypocalcemic syndrome: predictive value of early PTH. Preliminary results.

Aim: The aim of this study is to determine an early measured serous PTH cut-off value below which it's possible to predict post-thyroidectomy hypocalcaemia outbrake.

Materials Of Study: Ninety-three consecutive patients having a benign thyroid pathology were submitted to total thyroidectomy. In all the patients serous post-surgery intact PTH and total calcium were measured within an hour from weaning.

A modeling study suggesting how a reduction in the context-dependent input on CA1 pyramidal neurons could generate schizophrenic behavior.

The neural mechanisms underlying schizophrenic behavior are unknown and very difficult to investigate experimentally, although a few experimental and modeling studies suggested possible causes for some of the typical psychotic symptoms related to this disease. The brain region most involved in these processes seems to be the hippocampus, because of its critical role in establishing memories for objects or events in the context in which they occur. In particular, a hypofunction of the N-methyl-D-aspartate (NMDA) component of the synaptic input on the distal dendrites of CA1 pyramidal neurons has been suggested to play an important role for the emergence of schizophrenic behavior.

Functional roles of distributed synaptic clusters in the mitral-granule cell network of the olfactory bulb.

Odors are encoded in spatio-temporal patterns within the olfactory bulb, but the mechanisms of odor recognition and discrimination are poorly understood. It is reasonable to postulate that the olfactory code is sculpted by lateral and feedforward inhibition mediated by granule cells onto the mitral cells. Recent viral tracing and physiological studies revealed patterns of distributed granule cell synaptic clusters that provided additional clues to the possible mechanisms at the network level.

Reoperation for failed reflux surgery.

Common causes of failure for gastroesophageal reflux surgery, whether associated with hiatal hernia (HH) or not, include a too tight closure of the crurae, a too tight fundoplication, recurrent HH, total or partial disruption of the wrap and a slipped fundoplication in the chest or down onto the stomach. A laparoscopic approach to patients with failure or complication after antireflux surgery now represents the standard of care after a laparoscopic procedure. The transthoracic approach may be of added value after one or two reoperations, and remains a firm option in more complicated patients.

A computer model of unitary responses from associational/commissural and perforant path synapses in hippocampal CA3 pyramidal cells.

Despite the central position of CA3 pyramidal cells in the hippocampal circuit, the experimental investigation of their synaptic properties has been limited. Recent slice experiments from adult rats characterized AMPA and NMDA receptor unitary synaptic responses in CA3b pyramidal cells. Here, excitatory synaptic activation is modeled to infer biophysical parameters, aid analysis interpretation, explore mechanisms, and formulate predictions by contrasting simulated somatic recordings with experimental data.

Limited fatty infiltration due to apoptosis in human degenerated temporomandibular joint disks: an immunohistochemical study.

In this study, we hypothesized that caspase 3, which plays a central role in the execution phase of cell apoptosis, could be involved in limiting fatty degeneration of the temporomandibular joint (TMJ) disks and therefore inhibit the TMJ disk tissue from completely degenerating into fatty tissue. Therefore, caspase 3 immunohistochemical expression in human TMJ degenerated disks was studied. Fifty-nine degenerated TMJ disks were stained with Harry's hematoxylin, and they were then examined with light microscopy to detect any pathologic changes typical of fatty degeneration.

TRAIL, DR5 and caspase 3-dependent apoptosis in vessels of diseased human temporomandibular joint disc. An immunohistochemical study.

To evaluate the apoptosis involvement in the angiogenesis as a self-limiting process in patients with temporomandibular joint (TMJ) degenerated disc vessels, we assessed, by immunohistochemistry, the detection of TRAIL, its death receptor DR5 and caspase 3. TRAIL, its death receptor DR5 and caspase 3 expression were studied by immunohistochemistry in 15 TMJ discs displaced without reduction and in 4 unaffected discs. These apoptosis molecules were detected in the intima and media layers of newly formed vessels affected discs.

Abnormal Excitability of Oblique Dendrites Implicated in Early Alzheimer's: A Computational Study.

The integrative properties of cortical pyramidal dendrites are essential to the neural basis of cognitive function, but the impact of amyloid beta protein (abeta) on these properties in early Alzheimer's is poorly understood. In animal models, electrophysiological studies of proximal dendrites have shown that abeta induces hyperexcitability by blocking A-type K+ currents (I(A)), disrupting signal integration. The present study uses a computational approach to analyze the hyperexcitability induced in distal dendrites beyond the experimental recording sites.

Transcriptional-metabolic networks in beta-carotene-enriched potato tubers: the long and winding road to the Golden phenotype.

Vitamin A deficiency is a public health problem in a large number of countries. Biofortification of major staple crops (wheat [Triticum aestivum], rice [Oryza sativa], maize [Zea mays], and potato [Solanum tuberosum]) with β-carotene has the potential to alleviate this nutritional problem. Previously, we engineered transgenic "Golden" potato tubers overexpressing three bacterial genes for β-carotene synthesis (CrtB, CrtI, and CrtY, encoding phytoene synthase, phytoene desaturase, and lycopene β-cyclase, respectively) and accumulating the highest amount of β-carotene in the four aforementioned crops.

Role for hepatic and circulatory ST6Gal-1 sialyltransferase in regulating myelopoiesis.

Recent findings have established a role for the ST6Gal-1 sialyltransferase in modulating inflammatory cell production during Th1 and Th2 responses. ST6Gal-1 synthesizes the Sia(alpha2,6) to Gal(beta1,4)GlcNAc linkage on glycoproteins on cell surfaces and in systemic circulation. Engagement of P1, one of six promoter/regulatory regions driving murine ST6Gal-1 gene expression, generates the ST6Gal-1 for myelopoietic regulation.

Extending surgery for pulmonary metastasectomy: what are the limits?

Introduction: The purpose of pulmonary metastasectomy is to remove all known remaining cancer with the purpose of cure or to lengthen survival. Little information is available on the extent of surgery that is justified and or on reasonable evidence based limits to the extent of surgery.

Methods: A systematic review was designed to evaluate the role of extended surgery in the treatment of lung metastasis.

Altered architecture and functional consequences of the mesolimbic dopamine system in cannabis dependence.

Cannabinoid withdrawal produces a hypofunction of mesencephalic dopamine neurons that impinge upon medium spiny neurons (MSN) of the forebrain. After chronic treatment with two structurally different cannabinoid agonists, Delta(9)-tetrahydrocannabinol and CP55 940 (CP) rats were withdrawn spontaneously and pharmacologically with the CB1 antagonist SR141716A (SR). In these two conditions, evaluation of tyrosine hydroxylase (TH)-positive neurons revealed significant morphometrical reductions in the ventrotegmental area but not substantia nigra pars compacta of withdrawn rats.

Local control of postinhibitory rebound spiking in CA1 pyramidal neuron dendrites.

Postinhibitory rebound spiking is characteristic of several neuron types and brain regions, where it sustains spontaneous activity and central pattern generation. However, rebound spikes are rarely observed in the principal cells of the hippocampus under physiological conditions. We report that CA1 pyramidal neurons support rebound spikes mediated by hyperpolarization-activated inward current (I(h)), and normally masked by A-type potassium channels (K(A)).

FV-100: the most potent and selective anti-varicella zoster virus agent reported to date.

Bicyclic aryl furano pyrimidines represent the most potent anti-varicella zoster virus (VZV) agents reported to date. Lead compounds have 50% effective concentration (EC(50)) values in vitro that are in the subnanomolar range and selectivity index values that exceed 1 million. They have an absolute requirement for VZV thymidine kinase and most likely act as their phosphate forms.

Control of GABA Release at Mossy Fiber-CA3 Connections in the Developing Hippocampus.

In this review some of the recent work carried out in our laboratory concerning the functional role of GABAergic signalling at immature mossy fibres (MF)-CA3 principal cell synapses has been highlighted. While in adulthood MF, the axons of dentate gyrus granule cells release onto CA3 principal cells and interneurons glutamate, early in postnatal life they release GABA, which exerts into targeted cells a depolarizing and excitatory action. We found that GABA(A)-mediated postsynaptic currents (MF-GPSCs) exhibited a very low probability of release, were sensitive to L-AP4, a group III metabotropic glutamate receptor agonist, and revealed short-term frequency-dependent facilitation.

Clinical biomarkers in esophageal adenocarcinoma.

This review describes genetic and molecular changes related to adenocarcinoma of the esophagus and gastroesophageal junction (GEJ) with emphasis on prognostic value and possibilities for targeted therapy in clinical setting. The progression of Barrett's esophagus to adenocarcinoma has been the focus of particular scrutiny, and a number of potential tissue and serum-based disease biomarkers have emerged. Tissue biomarkers allowing risk stratification of Barrett's are reviewed as well as strategies currently being used to discover novel biomarkers that will facilitate the early detection of esophageal adenocarcinoma.

Cervico-mediastinal goiter: is telescopic exploration of the mediastinum (video mediastinoscopy) useful?

Surgeons are aware that most mediastinal goiters can be excised through a Kocher transverse collar incision, but in rare circumstances a partial-complete median sternotomy or a thoracotomy are mandatory. During an operation to remove a large cervico-mediastinal goiter (CMG) a profound, not massive, bleeding in the anterior mediastinum developed. Bleeding was unsuccessfully treated with packing.

Re-operations for failed anti-reflux surgery. Lessons from the past and prospects for the future.

Objective: The total number of re-operations for failed antireflux surgery is increasing dramatically worldwide. We reviewed our experience of re-operations for failed anti-reflux surgery to identify the factors contributing to unsuccessful re-operation which can be used in the era of laparoscopic surgery.

Method: One hundred twenty one patients were re-operated.