Region Of Lamina Research Articles

Biospeckle numerical assessment followed by speckle quality tests

The biospeckle or dynamic speckle phenomenon reflects the information regarding activity of both biological and non-biological material under study. However, due to having a complex interaction between light and material, the analysis of such phenomenon has been a challenge. This study therefore, presents quality tests of biospeckle data obtained from a Plumeria leaf surface, where it was possible to identify some problems in the images related to the tested features. In order to obtain speckle images of best quality, the saturation, the contrast and the homogeneity tests were carried out before the main analysis to be processed. In addition, we present numerical analysis of the biospeckle data to obtain biological information related to the activity of a leaf surface. Significant changes in biospeckle activities were observed. The activity distributions indicated the detection of higher activities around the midvein of the leaf. Activities measured using the IM and AVD values at midvein and lamina regions were found significantly different with a higher correlation observed with the AVD approach.

The expression of calcitonin gene-related peptide on the neurons associated Zusanli (ST 36) in rats.

To investigate the biochemical characteristic of the neurons associated Zusanli (ST 36) in the rat by using Alexa Fluor 594 conjugated cholera toxin subunit B (AF594-CTB) neural tracing and calcitonin gene-related peptide (CGRP) fluorescent immunohistochemical techniques. Four male Sprague Dawley rats were injected with AF594-CTB into the corresponding area of the Zusanli in the human body. After 3 surviving days, the rat's spinal cord and dorsal root ganglia (DRGs) at lumbar segments were dissected following perfusion with 4% paraformaldehyde, cut into sections, and then stained with CGRPfluorescent immunohistochemical method. AF594-CTB labeled sensory neurons were detected in the L3-L6 DRGs with high concentration in L4 DRG, and the labeled motor neurons located in the dorsolateral and intermediate regions of lamina IX from L3-L5 segments with high concentration at L4. Meanwhile, CGRPpositive neural labeling distributed symmetrically on both sides of DRGs, anterior and dorsal horns of spinal cord. In the AF594-CTB labeled neurons, 37% sensory neurons and 100% motor neurons expressed CGRPpositive. These findings present the morphological evidence to demonstrate that the sensory and motor neurons associated Zusanli in the rat distributed with segmental and regional patterns, and contained CGRP-expression.

Терапевтичний вплив Церебрала за умов нейродегенерації, викликаної порушенням функції гена swiss cheese у Drosophila melanogaster

It was found that Cerebral medicine has a therapeutic effect on aging of D. melanogaster individuals with neurodegeneration caused by altered functioning of swiss cheese gene ( sws ). After Сerebral treatment survival of old mutants sws olfE . was improved. Comparison of brain tissue histological sections of twenty days old males grown on standard nutrient medium and the medium with C. still showed manifestation of the mutant phenotype after application of the drug. However, penetrance of the neurodegenerative phenotype decreased by 10 % and this change correlated with an increase in the viability of aging individuals. We have created a functional knockout of sws gene in glial cells using Gal4-UAS system to test the effect of the drug in the conditions of shortage sws in glial cells. Genotype of such individual was Repo-Gal4>UAS-sws-RNAi . After analysis of these flies, we found specific pathology of glial phenotype, namely: considerable vacuolization in brain tissue in the region of the transition lamina to retina and medulla. In individuals with functional knockout of sws in glia, size of neurodegeneration area decreased by 34.5 % after Cerebral treatment, and 28.4 % in case of using its low molecular weight fraction. No significant differences in the effects of Cerebral and its low molecular weight fraction were found. Our results allow to conclude that the active component of C is its low molecular weight fraction. This drug may be effective in treatment of brain pathologies with a primary damage of glial cells. Keywords: neurodegeneration, Drosophila melanogaster , swiss cheese , Gal4-UAS functional inactivation, Cerebral.

82 STRUCTURAL REMODELLING OF THE NUCLEAR ENVELOPE IN BOVINE PRE-IMPLANTATION EMBRYOS

In the present study, we investigated the changes of the nuclear envelope and its underlying lamina, as well as features of higher order chromatin organisation in bovine embryos generated by in vitro fertilization during pre-implantation development. We used super-resolution, 3-dimensional structured illumination microscopy combined with 2-colour immunostaining of the nucleoporin Nup153 and lamin B serving as markers for nuclear pore complexes (NPC) and the nuclear lamina, respectively. DNA was counterstained with 4′,6-diamidino-2-phenylindole (DAPI). We examined 20 nuclei for the zygote (10 male pronuclei and 10 female pronuclei; n = 10) and the blastocyst (10 trophectoderm and 10 inner cell mass nuclei; n = 1) stage, and 10 nuclei for each the 2-cell (n = 5), 4-cell (n = 3), 8-cell (n = 2), 19-cell (n = 1), and morula (n = 1) stages. We report 4 major findings: (1) At the onset of major genome activation (MGA) nuclei showed a peripheral location of chromosome territories (CT), separated by wide IC channels and surrounding a major lacuna depleted of chromatin. The NPC were exclusively present at sites where DAPI-stained DNA contacted the nuclear lamina, whereas extended lamina regions without such contacts lacked NPC. In post-MGA nuclei, the CT formed a higher order chromatin network distributed throughout the entire nuclear space and the major lacuna disappeared. In line with a switch to a ubiquitous lining of DNA at the lamina, NPC were also uniformly distributed throughout the entire nuclear envelope. These findings shed new light on the conditions that control the integration of NPC into the nuclear envelope. (2) The switch from maternal to embryonic production of mRNA was accompanied by an increased amount of nuclear lamina invaginations covered with NPC, which may serve the increased demands of mRNA export and protein import. (3) Other invaginations, as well as interior nuclear segments and vesicles without contact to the nuclear envelope, were exclusively positive for lamin B. Because an increase in these lamin B positive structures occurred in concert with a massive nuclear volume reduction, we suggest that they reflect a mechanism for fitting the nuclear envelope and its lamina to a shrinking nuclear size throughout bovine pre-implantation development. (4) Throughout the cytoplasm, randomly distributed extranuclear clusters of Nup153 without associated lamin B were frequently observed from the zygote stage up to MGA. These clusters may represent a deposit of maternal Nup153 and likely other nucleoporines not studied here. Corresponding RNA-Seq data revealed deposits of spliced, maternally provided NUP153 mRNA and little unspliced RNA before MGA, which increased strongly at the initiation of embryonic NUP153 expression at MGA. After MGA, these clusters were exclusively located at or near the nuclear border and were no longer present at the morula stage and later. In conclusion, our findings demonstrate the dynamic adaptation of the nuclear envelope to the special needs of bovine pre-implantation development and show the necessity of chromatin association for the integration of nuclear pores into the nuclear envelope.

Effects of location and timing of co-activated neurons in the auditory midbrain on cortical activity: implications for a new central auditory prosthesis

Objective. An increasing number of deaf individuals are being implanted with central auditory prostheses, but their performance has generally been poorer than for cochlear implant users. The goal of this study is to investigate stimulation strategies for improving hearing performance with a new auditory midbrain implant (AMI). Previous studies have shown that repeated electrical stimulation of a single site in each isofrequency lamina of the central nucleus of the inferior colliculus (ICC) causes strong suppressive effects in elicited responses within the primary auditory cortex (A1). Here we investigate if improved cortical activity can be achieved by co-activating neurons with different timing and locations across an ICC lamina and if this cortical activity varies across A1. Approach. We electrically stimulated two sites at different locations across an isofrequency ICC lamina using varying delays in ketamine-anesthetized guinea pigs. We recorded and analyzed spike activity and local field potentials across different layers and locations of A1. Results. Co-activating two sites within an isofrequency lamina with short inter-pulse intervals (<5 ms) could elicit cortical activity that is enhanced beyond a linear summation of activity elicited by the individual sites. A significantly greater extent of normalized cortical activity was observed for stimulation of the rostral–lateral region of an ICC lamina compared to the caudal–medial region. We did not identify any location trends across A1, but the most cortical enhancement was observed in supragranular layers, suggesting further integration of the stimuli through the cortical layers. Significance. The topographic organization identified by this study provides further evidence for the presence of functional zones across an ICC lamina with locations consistent with those identified by previous studies. Clinically, these results suggest that co-activating different neural populations in the rostral–lateral ICC rather than the caudal–medial ICC using the AMI may improve or elicit different types of hearing capabilities.

Activation of Organum Vasculosum of Lamina Terminalis, Median Preoptic Nucleus, and Medial Preoptic Area in Anticipation of Nursing in Rabbit Pups

Rhythmic feeding in rabbit pups is a natural model to study food entrainment because, similar to rodents under a schedule of food restriction, these animals show food-anticipatory activity (FAA) prior to daily nursing. In rodents, several brain systems, including the orexinergic system, shift their activity to the restricted feeding schedule, and remain active when subjects are hungry. As the lamina terminalis and regions of the preoptic area participate in the control of behavioral arousal, it was hypothesized that these brain regions are also activated during FAA. Thus, the effects of daily milk ingestion on FOS protein expression in the organum vasculosum of lamina terminalis (OVLT), median preoptic nucleus (MnPO), and medial preoptic area (MPOA) were examined using immunohistochemistry before and after scheduled time of nursing in nursed and fasted subjects. Additionally, FOS expression was explored in orexin (ORX) cells in the lateral hypothalamic area and in the supraoptic nucleus (SON) because of their involvement in arousal and fluid ingestion, respectively. Pups were entrained by daily nursing, as indicated by a significant increase in locomotor behavior before scheduled time of nursing in both nursed and fasted subjects. FOS was significantly higher in the OVLT, MnPO, and MPOA at the time of nursing, and decreased 8 h later in nursed pups. In fasted subjects, this effect persisted in the OVLT, whereas in the MnPO and MPOA, values did not drop at 8 h later, but remained at the same level or higher than those at the time of scheduled nursing. In addition, FOS was significantly higher in ORX cells during FAA in nursed pups in comparison with 8 h later, but in fasted subjects it remained high during most fasting time points. Additionally, OVLT, SON, and ORX cells were activated 1.5 h after nursing. We conclude that the OVLT, MnPO, and MPOA, but not SON, may participate in FAA, as they show activation before suckling of periodic milk ingestion, and that sustained activation of the OVLT, MnPO, and MPOA by fasting may contribute to the high arousal state associated with food deprivation. In agreement with this, ORX cells also remain active after expected nursing, which is consistent with reports in other species.

Organized Emergence of Multiple-Generations of Teeth in Snakes Is Dysregulated by Activation of Wnt/Beta-Catenin Signalling

In contrast to mammals, most reptiles constantly regenerate their teeth. In the snake, the epithelial dental lamina ends in a successional lamina, which proliferates and elongates forming multiple tooth generations, all linked by a permanent dental lamina. To investigate the mechanisms used to control the initiation of new tooth germs in an ordered sequential pattern we utilized the polyphodont (multiple-generation) corn snake (Pantherophis guttatus). We observed that the dental lamina expressed the transcription factor Sox2, a multipotent stem cell marker, whereas the successional lamina cells expressed the transcription factor Lef1, a Wnt/β-catenin pathway target gene. Activation of the Wnt/β-catenin pathway in culture increased the number of developing tooth germs, in comparison to control untreated cultures. These additional tooth germs budded off from ectopic positions along the dental lamina, rather than in an ordered sequence from the successional lamina. Wnt/β-catenin activation enhanced cell proliferation, particularly in normally non-odontogenic regions of the dental lamina, which widely expressed Lef1, restricting the Sox2 domain. This suggests an expansion of the successional lamina at the expense of the dental lamina. Activation of the Wnt/β-catenin pathway in cultured snake dental organs, therefore, led to changes in proliferation and to the molecular pattern of the dental lamina, resulting in loss of the organised emergence of tooth germs. These results suggest that epithelial compartments are critical for the arrangement of organs that develop in sequence, and highlight the role of Wnt/β-catenin signalling in such processes.

The modality‐specific contribution of peptidergic and non‐peptidergic nociceptors is manifest at the level of dorsal horn nociresponsive neurons

We previously demonstrated that genetic and/or pharmacological ablation of the TRPV1+/peptidergic or the MrgprD+/non-peptidergic subset of nociceptors produced selective, modality-specific deficits in the behavioural responses to heat and mechanical stimuli, respectively. To assess whether this modality-specific contribution is also manifest at the level of spinal cord neuron responsiveness, here we made extracellular recordings from lumbar dorsal horn neurons of the mouse in response to graded thermal and mechanical stimulation. We found that, following intrathecal injection of capsaicin to eliminate the central terminals of TRPV1+ nociceptors, neurons in the region of laminae I and V of the spinal cord lost responsiveness to noxious heat (whether generated by a contact heat probe or diode laser), with no change in their response to noxious mechanical stimulation. In contrast, ablation of MrgprD+ afferents did not alter the response to noxious heat, but reduced the firing of superficial dorsal horn nociceptive-specific neurons in response to graded mechanical stimulation and decreased the relative number of wide dynamic range neurons that were exclusively mechanosensitive. Neither ablation procedure reduced the number of dorsal horn neurons that responded to noxious cold. These findings support the conclusion that TRPV1+ nociceptors are necessary and probably sufficient for noxious heat activation of dorsal horn neurons and that, despite their polymodal properties, TRPV1+ and MrgprD+ nociceptors provide modality-specific contributions to the response properties of spinal cord neurons.

Central Venous Pulsations

The translaminar pressure gradient (TLPG) is largely influenced by the difference between intraocular pressure (IOP) and cerebrospinal fluid pressure (CSFP), but modulated by the buffering effect of orbital tissue and pia mater, which limits the reduction in retrolaminar tissue pressure as intracranial CSFP falls below 0 mm Hg. Across the lamina cribrosa, the central retinal vein experiences the greatest pressure gradient (TLPG) of any vein in the body. When CSFP rises, the minimum IOP required to induce venous pulsation pressure (VPP) rises with CSFP (r=0.95, slope=0.90). Lowering IOP in glaucoma patients leads to a reduction in VPP (P=0.0003). The normal human central retinal vein endothelial cells in the lamina region resemble typical arterial endothelia and are quite unlike other venous cells. It is likely that the TLPG is increasing retinal vein shear and in glaucoma this effect is likely to be increased with possible wall effects.

Ultrastructure and molecular pathogenesis of epidermolysis bullosa

Epidermolysis bullosa (EB) is classified into the three major subtypes depending on the level of skin cleavage within the epidermal keratinocyte or basement membrane zone. Tissue separation occurs within the intraepidermal cytoplasm of the basal keratinocyte, through the lamina lucida, or in sublamina densa regions of the basal lamina (basement membrane) in EB simplex, junctional EB, and dystrophic EB, respectively. Transmission electron microscopy (TEM) is an effective method for determining the level of tissue separation and hemidesmosome (HD) and anchoring fibril morphology if performed by experienced operators, and has proven to be a powerful technique for the diagnosis of new EB patients. Recent advances in genetic and immunofluorescence studies have enabled us to diagnose EB more easily and with greater accuracy. This contribution reviews TEM findings in the EB subtypes and discusses the importance of observations in the molecular morphology of HD and basement membrane associated structures.

Red (anthocyanic) leaf margins do not correspond to increased phenolic content in New Zealand Veronica spp.

Red or purple coloration of leaf margins is common in angiosperms, and is found in approx. 25 % of New Zealand Veronica species. However, the functional significance of margin coloration is unknown. We hypothesized that anthocyanins in leaf margins correspond with increased phenolic content in leaf margins and/or the leaf entire, signalling low palatability or leaf quality to edge-feeding insects. Five species of Veronica with red leaf margins, and six species without, were examined in a common garden. Phenolic content in leaf margins and interior lamina regions of juvenile and fully expanded leaves was quantified using the Folin-Ciocalteu assay. Proportions of leaf margins eaten and average lengths of continuous bites were used as a proxy for palatability. Phenolic content was consistently higher in leaf margins compared with leaf interiors in all species; however, neither leaf margins nor more interior tissues differed significantly in phenolic content with respects to margin colour. Mean phenolic content was inversely correlated with the mean length of continuous bites, suggesting effective deterrence of grazing. However, there was no difference in herbivore consumption of red and green margins, and the plant species with the longest continuous grazing patterns were both red-margined. Red margin coloration was not an accurate indicator of total phenolic content in leaf margins or interior lamina tissue in New Zealand Veronica. Red coloration was also ineffective in deterring herbivory on the leaf margin, though studies controlling for variations in leaf structure and biochemistry (e.g. intra-specific studies) are needed before more precise conclusions can be drawn. It is also recommended that future studies focus on the relationship between anthocyanin and specific defence compounds (rather than general phenolic pools), and evaluate possible alternative functions of red margins in leaves (e.g. antioxidants, osmotic adjustment).

Colitis induces calcitonin gene-related peptide expression and Akt activation in rat primary afferent pathways

Previous study has shown that colitis-induced increases in calcitonin gene-related peptide (CGRP) immunoreactivity in bladder afferent neurons result in sensory cross-sensitization. To further determine the effects of colitis on CGRP expression in neurons other than bladder afferents, we examined and compared the levels of CGRP mRNA and immunoreactivity in the lumbosacral dorsal root ganglia (DRG) and spinal cord before and during colitis in rats. We also examined the changes in CGRP immunoreactivity in colonic afferent neurons during colitis. Results showed increases in CGRP mRNA levels in L1 (2.5-fold, p < 0.05) and S1 DRG (1.9–2.4-fold, p < 0.05). However, there were no changes in CGRP mRNA levels in L1 and S1 spinal cord during colitis. CGRP protein was significantly increased in L1 (2.5-fold increase, p < 0.05) but decreased in S1 (50% decrease, p < 0.05) colonic afferent neurons, which may reflect CGRP release from these neurons during colitis. In L1 spinal cord, colitis caused increases in the number of CGRP nerve fibers in the deep lamina region extending to the gray commissure where the number of phospho-Akt neurons was also increased. In S1 spinal cord, colitis caused the increases in the intensity of CGRP fibers in the regions of dorso-lateral tract, and caused the increases in the level of phospho-Akt in the superficial dorsal horn of the spinal cord. In spinal cord slice culture, exogenous CGRP increased the phosphorylation level of Akt but not the phosphorylation level of extracellular-signal regulated kinase ERK1/2 even though our previous studies showed that colitis increased the phosphorylation level of ERK1/2 in L1 and S1 spinal cord. These results suggest that CGRP is synthesized in the DRG and may transport to the spinal cord where it initiates signal transduction during colitis.

Distribution and Localization of 5-HT1AReceptors in the Rat Lumbar Spinal Cord after Transection and Deafferentation

The serotonergic system is highly plastic, capable of adapting to changing afferent information in diverse mammalian systems. We hypothesized that removing supraspinal and/or peripheral input would play an important role in defining the distribution of one of the most prevalent serotonergic receptors, the 5-HT(1A) receptor (R), in the spinal cord. We investigated the distribution of this receptor in response to a complete thoracic (T7-T8) spinal cord transection (eliminating supraspinal input), or to spinal cord isolation (eliminating both supraspinal and peripheral input) in adult rats. Using two antibodies raised against either the second extracellular region (ECL(2)) or the third intracellular region (ICL(3)) of the 5-HT(1A)R, we compared the 5-HT(1A)R levels and distributions in specific laminae of the L3-L5 segments among the control, spinal cord-transected, and spinal cord-isolated groups. Each antibody labeled different populations of 5-HT(1A)R: ECL(2) labeled receptors in the axon hillock, whereas ICL(3) labeled receptors predominantly throughout the soma and proximal dendrites. Spinal cord transection increased the number of ECL(2)-positive cells in the medial region of laminae III-IV and lamina VII, and the mean length of the labeled axon hillocks in lamina IX. The number of ICL(3)-labeled cells was higher in lamina VII and in both the medial and lateral regions of lamina IX in the spinal cord-transected compared to the control group. In contrast, the length and number of ECL(2)-immunolabeled processes and ICL(3)-immunolabeled cells were similar in the spinal cord-isolated and control groups. Combined, these data demonstrate that the upregulation in 5-HT(1A)R that occurs with spinal cord transection alone is dependent on the presence of sensory input.

Heat‐induced electrical signals affect cytoplasmic and apoplastic pH as well as photosynthesis during propagation through the maize leaf

Combining measurements of electric potential and pH with such of chlorophyll fluorescence and leaf gas exchange showed heat stimulation to evoke an electrical signal (propagation speed: 3-5 mm s(-1)) that travelled through the leaf while reducing the net CO(2) uptake rate and the photochemical quantum yield of both photosystems (PS). Two-dimensional imaging analysis of the chlorophyll fluorescence signal of PS II revealed that the yield reduction spread basipetally via the veins through the leaf at a speed of 1.6 +/- 0.3 mm s(-1) while the propagation speed in the intervein region was c. 50 times slower. Propagation of the signal through the veins was confirmed because PS I, which is present in the bundle sheath cells around the leaf vessels, was affected first. Hence, spreading of the signal along the veins represents a path with higher travelling speed than within the intervein region of the leaf lamina. Upon the electrical signal, cytoplasmic pH decreased transiently from 7.0 to 6.4, while apoplastic pH increased transiently from 4.5 to 5.2. Moreover, photochemical quantum yield of isolated chloroplasts was strongly affected by pH changes in the surrounding medium, indicating a putative direct influence of electrical signalling via changes of cytosolic pH on leaf photosynthesis.

The Functional Role of the Hollow Region of the Butterfly Pyrameis atalanta (L.) Scale

Questions concerning the functional role of the hollow region of the butterfly Pyrameis atalanta (L.) scale are experimentally investigated. Attention was initially directed to this problem by observation of the complex microstructure of the butterfly scale as well as other studies indicating higher lift on butterfly wings covered with scale. The aerodynamic forces were measured for two oscillating scale models. Results indicated that the air cavity of an oscillating model of the Pyrameis atalanta (L.) scale increased the lift by a factor of 1.15 and reduced the damping coefficients by a factor of 1.38. The modification of the aerodynamic effects on the model of butterfly scale was due to an increase of the virtual air mass, which influenced the body. The hollow region of the scale increased the virtual air mass by a factor of 1.2. The virtual mass of the butterfly scale with the hollow region was represented as the sum of air mass of two imaginary geometrical figures: a circular cylinder around the scale and a right-angled parallelepiped within the hollow region. The interaction mechanism of the butterfly Pyrameis atalanta (L.) scale with a flow was described. This novel interaction mechanism explained most geometrical features of the airpermeable butterfly scale (inverted V-profile of the ridges, nozzle of the tip edge, hollow region, and openings of the upper lamina) and their arrangement.

Tissue-dependent subcellular localization of Drosophila arginine methyl-transferase 4 (DART4), a coactivator whose overexpression affects neither viability nor differentiation

Drosophila arginine methyl- transferase 4 (DART4) belongs to the type I class of arginine methyltransferases. It catalyzes the methylation of arginine residues to monomethylarginines and asymmetrical dimethylarginines. The DART4 sequence is highly similar to mammalian PRMT4/CARM1, and DART4 substrate specificity has been conserved, too. Recently it was suggested that DART4/Carmer functions in ecdysone receptor mediated apoptosis of the polytene larval salivary glands and an apparent up-regulation of DART4/ Carmer mRNA levels before tissue histolysis was reported. Here we show that in Drosophila larvae, DART4 is mainly expressed in the imaginal disks and in larval brains, and to a much lesser degree in the polytene larval tissue such as salivary glands. In glands, DART4 protein is present in the cytoplasm and the nucleus. The nuclear signal emanates from the extrachromosomal domain and gets progressively restricted to the region of the nuclear lamina upon pupariation. Surprisingly, DART4 levels do not increase in salivary glands during pupariation, and overexpression of DART4 does not cause precautious cell death in the glands. Furthermore, over- and misexpression of DART4 under the control of the α tubulin promoter do not lead to any major problem in the life of a fly. This suggests that DART4 activity is regulated at the posttranslational level and/or that it acts as a true cofactor in vivo. We present evidence that nuclear localization of DART4 may contribute to its function because DART4 accumulation changes from a distribution with a strong cytoplasmic component during the transcriptional quiescence of the young embryo to a predominantly nuclear one at the onset of zygotic transcription.

Pain behaviors after spinal cord contusion injury in two commonly used mouse strains

We have characterized spontaneous and evoked pain behaviors that develop in a model of severe spinal contusion injury using two commonly used strains of mice. Using the Infinite Horizon Tissue Impactor to produce these contusion injuries, we were able to set strict limits on the injury parameters (i.e., force of impact and tissue displacement). This helps to generate a uniform population of spinal cord injury severity and allows for meaningful comparisons to be made across the two strains of mice. After contusion injury, strain differences were apparent in several injury-evoked behaviors such as hindlimb spasticity, spontaneous caudally directed nociceptive behaviors and over-grooming. Similar to the anatomical rearrangements observed in the rat after spinal cord injury, we observed significant changes in sensory innervation of the dorsal horn in both strains. In addition, there was increased expression of protein kinase C gamma (PKCγ) in cells outside of the inner region of lamina II (IIi) in both strains after spinal contusion injury. However, the magnitude and intensity of this increase was more pronounced in BALB/c mice. PKCγ is an important mediator of persistent pain behaviors after peripheral nerve injury and inflammation. Our results suggest that PKCγ may also contribute to neuropathic pain behaviors after direct lesion to the spinal cord.

U S 3 of Herpes Simplex Virus Type 1 Encodes a Promiscuous Protein Kinase That Phosphorylates and Alters Localization of Lamin A/C in Infected Cells

The herpes simplex virus type 1 (HSV-1) US3 gene encodes a serine/threonine kinase that, when inactivated, causes capsids to aggregate aberrantly between the inner and outer nuclear membranes (INM and ONM, respectively) within evaginations/extensions of the perinuclear space. In both Hep2 cells and an engineered cell line derived from Hep2 cells expressing lamin A/C fused to enhanced green fluorescent protein (eGFP-lamin A/C), lamin A/C localized mostly in a reticular pattern with small regions of the INM devoid of eGFP-lamin A/C when they were either mock infected or infected with wild-type HSV-1(F). Cells infected with HSV-1(F) also contained some larger diffuse regions lacking lamin A/C. Proteins UL31 and UL34, markers of potential envelopment sites at the INM and perinuclear virions, localized within the regions devoid of lamin A/C and also in regions containing lamin A/C. Similar to previous observations with Vero cells (S. L. Bjerke and R. J. Roller, Virology 347:261-276, 2006), the proteins UL34 and UL31 localized exclusively in very discrete regions of the nuclear lamina lacking lamin A/C in the absence of US3 kinase activity. To determine how US3 alters lamin A/C distribution, US3 was purified and shown to phosphorylate lamin A/C at multiple sites in vitro, despite the presence of only one putative US3 kinase consensus site in the lamin A/C sequence. US3 kinase activity was also sufficient to invoke partial solubilization of lamin A/C from permeabilized Hep2 cell nuclei in an ATP-dependent manner. Two-dimensional electrophoretic analyses of lamin A/C revealed that lamin A/C is phosphorylated in HSV-infected cells, and the full spectrum of phosphorylation requires US3 kinase activity. These data suggest that US3 kinase activity regulates HSV-1 capsid nuclear egress at least in part by phosphorylation of lamin A/C.

Schizophrenia seen as a deficit in the modulation of cortical minicolumns by monoaminergic systems

The highly evolved architecture of the cerebral cortex is organized across hierarchical levels that maximize functional repertoires (emergent properties) and expedite information processing. Minicolumns are nested within this multiscale architecture as the smallest module capable of processing information. Signals are transmitted within minicolumns through massive ion-gated connections and modulated through slower onset second messenger systems. The terminal zones of the modulatory second messenger systems comprise the laminae of the cortex. A comprehensive review of the literature suggests that schizophrenia results from widely distributed changes at the level of the cerebral cortex and little, if any, neuronal somatic changes: (Esiri & Crow, ). Concordant with this observation recent studies indicate that schizophrenic patients have an alteration of neuronal connectivity according to both lamina and brain region examined. One possible explanation for this deficit is an alteration in the modulatory system of cortical minicolumns. This ontogenetic deficit propitiates a cascade of neurochemical changes resulting in varying abnormalities relating information processing to behavioural states.

Differential Projections of Excitatory and Inhibitory Dorsal Horn Interneurons Relaying Information from Group II Muscle Afferents in the Cat Spinal Cord

Dorsal horn interneurons with input from group II muscle spindle afferents are components of networks involved in motor control. Thirteen dorsal horn interneurons with monosynaptic group II input were characterized electrophysiologically and labeled intracellularly with Neurobiotin. Their axonal projections were traced, and neurotransmitter content was established by using immunocytochemistry. Two subpopulations were identified: five interneurons had axons that contained vesicular glutamate transporter 2 and hence were glutamatergic and excitatory. Terminals of the remaining eight interneurons were immunoreactive for the glycine transporter 2 or were apposed to gephyrin but did not contain the GABA-synthesizing enzyme glutamic acid decarboxylase and were therefore glycinergic and inhibitory. Excitatory cells were located mainly in the central region of lamina IV and had relatively small somata and restricted dendritic trees. In contrast, inhibitory interneurons were located more ventrally, in lamina V and had relatively larger somata and more extensive dendritic trees. Axonal projections of the two subpopulations differed considerably. Excitatory interneurons predominantly projected ipsilaterally, whereas most inhibitory interneurons projected both ipsilaterally and contralaterally. Three inhibitory axons formed contacts with large cholinergic cells in motor nuclei, thus revealing a novel direct coupling between inhibitory dorsal horn interneurons and motoneurons. The organization of the excitatory interneurons is consistent with current knowledge of reflex pathways to motoneurons, but the existence and connections of the inhibitory subpopulation could not be predicted from previous data. Our results indicate that these latter interneurons exercise widespread inhibitory control over a variety of cell types located on both sides of the spinal cord.