Mature miR-184 as Potential Oncogenic microRNA of Squamous Cell Carcinoma of Tongue

PURPOSE

The aim of this study was to evaluate the microRNA expression patterns in squamous cell carcinoma (SCC) of the tongue.

EXPERIMENTAL DESIGN

Expression levels of 156 human mature microRNAs were examined using real-time quantitative PCR (Taq Man MicroRNA Assays; Human Panel) on laser microdissected cells of 4 tongue carcinomas and paired normal tissues. Expression of mature miR-184 was further validated in 20 paired tongue SCC and the normal tissues. Potential oncogenic functions of miR-184 were evaluated in tongue SCC cell lines (Cal27, HN21B, and HN96) with miR-184 inhibitor. Plasma miR-184 levels were evaluated using real-time quantitative PCR.

RESULTS

Using 3-fold expression difference as a cutoff level, we identified 24 up-regulated mature miRNAs including miR-184, miR-34c, miR-137, miR-372, miR-124a, miR-21, miR-124b, miR-31, miR-128a, miR-34b, miR-154, miR-197, miR-132, miR-147, miR-325, miR-181c, miR-198, miR-155, miR-30a-3p, miR-338, miR-17-5p, miR-104, miR-134, and miR-213; and 13 down-regulated mature miRNAs including miR-133a, miR-99a, miR-194, miR-133b, miR-219, miR-100, miR-125b, miR-26b, miR-138, miR-149, miR-195, miR-107, and miR-139. Overexpression of miR-184 was further validated in 20 paired tongue SCC and normal tissues (P = 0.002). Inhibition of miR-184 in tongue SCC cell lines could reduce cell proliferation rate. Down-regulation of c-Myc was observed in two cell lines in response to miR-184 inhibitor. Suppressing miR-184 could induce apoptosis in all three cell lines. Plasma miR-184 levels were significantly higher in tongue SCC patients in comparison with normal individuals, and the levels were significantly reduced after surgical removal of the primary tumors.

CONCLUSIONS

Overexpression of miR-184 might play an oncogenic role in the antiapoptotic and proliferative processes of tongue SCC. In addition, plasma miR-184 levels were associated with the presence of primary tumor. Further studies on the aberrantly expressed miRNAs in tongue SCC as well as using plasma miRNAs as novel tumor markers are warranted.

Differences in quantal amplitude reflect GluR4- subunit number at corticothalamic synapses on two populations of thalamic neurons

Low-frequency thalamocortical oscillations that underlie drowsiness and slow-wave sleep depend on rhythmic inhibition of relay cells by neurons in the reticular nucleus (RTN) under the influence of corticothalamic fibers that branch to innervate RTN neurons and relay neurons. To generate oscillations, input to RTN predictably should be stronger so disynaptic inhibition of relay cells overcomes direct corticothalamic excitation. Amplitudes of excitatory postsynaptic conductances (EPSCs) evoked in RTN neurons by minimal stimulation of corticothalamic fibers were 2.4 times larger than in relay neurons, and quantal size of RTN EPSCs was 2.6 times greater. GluR4-receptor subunits labeled at corticothalamic synapses on RTN neurons outnumbered those on relay cells by 3.7 times, providing a basis for differences in synaptic strength.

Localization of alpha type II calcium calmodulin-dependent protein kinase at glutamatergic but not gamma-aminobutyric acid (GABAergic) synapses in thalamus and cerebral cortex

The alpha subunit of type II calcium/calmodulin-dependent protein kinase (CAM II kinase-alpha) plays an important role in longterm synaptic plasticity. We applied preembedding immunocytochemistry (for CAM II kinase-alpha) and postembedding immunogold labeling [for glutamate or gamma-aminobutyric acid (GABA)] to explore the subcellular relationships between transmitter-defined axon terminals and the kinase at excitatory and inhibitory synapses in thalamus and cerebral cortex. Many (but not all) axon terminals ending in asymmetric synapses contained presynaptic CAM II kinase-alpha immunoreactivity; GABAergic terminals ending in symmetric synapses did not. Postsynaptically, CAM II kinase-alpha immunoreactivity was associated with postsynaptic densities of many (but not all) glutamatergic axon terminals ending on excitatory neurons. CAM II kinase-alpha immunoreactivity was absent at postsynaptic densities of all GABAergic synapses. The findings show that CAM II kinase-alpha is selectively expressed in subpopulations of excitatory neurons and, to our knowledge, demonstrate for the first time that it is only associated with glutamatergic terminals pre- and postsynaptically. CAM II kinase-alpha is unlikely to play a role in plasticity at GABAergic synapses.

Regulation of reticuloendothelial iron transporter MTP1 (Slc11a3) by inflammation

Acute and chronic inflammation cause many changes in total body iron metabolism including the sequestration of iron in phagocytic cells of the reticuloendothelial system. This change in iron metabolism contributes to the development of the anemia of inflammation. MTP1, the duodenal enterocyte basolateral iron exporter, is also expressed in the cells of the reticuloendothelial system (RES) and is likely to be involved in iron recycling of these cells. In this study, we use a lipopolysaccharide model of the acute inflammation in the mouse and demonstrate that MTP1 expression in RES cells of the spleen, liver, and bone marrow is down-regulated by inflammation. The down-regulation of splenic expression of MTP1 by inflammation was also observed in a Leishmania donovani model of chronic infection. The response of MTP1 to lipopolysaccharide (LPS) requires signaling through the LPS receptor, Toll-like receptor 4 (TLR4). In mice lacking TLR4, MTP1 expression is not altered in response to LPS. In addition, mice lacking tumor necrosis factor-receptor 1a respond appropriately to LPS with down-regulation of MTP1, despite hyporesponsiveness to tumor necrosis factor-alpha signaling, suggesting that this cytokine may not be required for the LPS effect. We hypothesize that the iron sequestration in the RES system that accompanies inflammation is because of down-regulation of MTP1.

Identification of pyruvate kinase type M2 as potential oncoprotein in squamous cell carcinoma of tongue through microRNA profiling

MicroRNAs (miRNAs) are noncoding RNAs with specific regulatory role in gene expression. Recent reports suggested their involvement in human malignancies. Currently, there is no information concerning miRNA expression and functions in squamous cell carcinoma (SCC) of tongue. In this study, we evaluated the expression patterns of 156 mature miRNAs in tongue SCC using Taqman-based microRNA assays. Of these 156 miRNAs, miR-133a and miR-133b were significantly reduced in tongue SCC cells in comparison with the paired normal epithelial cells. Tongue SCC cell lines transfected with miR-133a and miR-133b precursors displayed reduction in proliferation rate. In addition, the number of apoptotic cells was increased in response to the introduction of precursors. Computational target gene prediction suggested that both miR-133a and miR-133b are targeting transcript of pyruvate kinase type M2 (PKM2), a potential oncogene in solid cancers. In tongue SCC cell lines, PKM2 expression was reduced in response to miR-133a and miR-133b precursors transfection. Immunohistochemical staining results of tongue SCC tissues suggested that PKM2 was overexpressed in tongue SCC and was associated with the downregulation of miR-133a and miR-133b. Our results suggested that aberrant reduction of miR-133a and miR-133b was associated with the dysregulation of PKM2 in SCC of tongue.

Distribution of four types of synapse on physiologically identified relay neurons in the ventral posterior thalamic nucleus of the cat

This study was aimed at providing quantitative data on the thalamic circuitry that underlies the central processing of somatosensory information. Four physiologically identified thalamocortical relay neurons in the ventral posterior lateral nucleus (VPL) of the cat thalamus were injected with horseradish peroxidase and subjected to quantitative electron microscopy after pre- or postembedding immunostaining for gamma-aminobutyric acid to reveal synaptic terminals of thalamic inhibitory neurons. The four cells all had rapidly adapting responses to light mechanical stimuli applied to their receptive fields, which were situated on hairy or glabrous skin or related to a joint. Their dendritic architecture was typical of cells previously described as type I relay cells in VPL, and they lacked dendritic appendages. Terminals ending in synapses on the injected cells were categorized as RL (ascending afferent), F (inhibitory), PSD (presynaptic dendrite), and RS (mainly corticothalamic) types and were quantified in reconstructions of serial thin sections. RL and F terminals formed the majority of the synapses on proximal dendrites (approximately 50% each). The number of synapses formed by RL terminals declined on intermediate dendrites, but those formed by F terminals remained relatively high, declining to moderate levels (20-30%) on distal dendrites. RS terminals formed moderate numbers of the synapses on intermediate dendrites and the majority (> 60%) of the synapses on distal dendrites. Synapses formed by PSDs were concentrated on intermediate dendrites and were few in number (approximately 6%). They formed synaptic triads with F terminals and rarely with RL terminals. On somata, only a few synapses were found, all made by F terminals. The total number of synapses per cell was calculated to be 5,584-8,797, with a density of 0.6-0.9 per micrometer of dendritic length. Of the total, RL terminals constituted approximately 15%, F terminals approximately 35%, PSD terminals approximately 5%, and RS terminals approximately 50%. These results provide the first quantitative assessment of the synaptic architecture of thalamic somatic sensory relay neurons and show the basic organizational pattern exhibited by representatives of the physiological type of relay neurons most commonly encountered in the VPL nucleus.

Synaptic distribution of afferents from reticular nucleus in ventroposterior nucleus of cat thalamus

This study was aimed at determining the synaptic circuitry that contributes to the alterations in thalamic function that accompany changes in behavioral states. The somatosensory sector of the thalamic reticular nucleus (RTN) was identified by microelectrode recording in cats and injected with Phaseolus vulgaris-leucoagglutinin (PHA-L). The axons of labeled RTN cells gave rise to collaterals within the RTN and continued into the dorsal thalamus where they terminated predominately in the ventral posterior lateral nucleus (VPL). After small injections in the upper limb representation of RTN, most labeled terminations in VPL were confined to its medial part, suggesting the presence of a topographic organization in the projection. Terminations were concentrated in localized, focal aggregations of boutons. Combined electron microscopic immunocytochemistry, using immunogold labeling for gamma-aminobutyric acid (GABA), showed that the PHA-L labeled boutons were GABA-positive terminals that ended in symmetrical synapses. Eighty-two percent of these synapses were on dendrites of relay neurons, 8.5% on dendrites of interneurons, and 9.3% on somata. The terminals of RTN axons form the majority of axon terminals ending in symmetrical synapses in VPL. Their concentration on relay neurons probably underlies the capacity of the RTN projection to reduce background activity of VPL relay neurons in the awake state and to maintain oscillatory behavior of these neurons in drowsiness and early phases of sleep.

Regulation of hepcidin and ferroportin expression by lipopolysaccharide in splenic macrophages

Acute and chronic inflammatory states are associated with many changes in intracellular iron metabolism including sequestration of iron in the mononuclear-phagocyte system (MPS) and a decline in serum iron. Previous work in rodent models of acute inflammation has demonstrated inflammation-induced downregulation of intestinal and MPS iron exporter, ferroportin 1, mRNA and protein. In addition, these models have also demonstrated hepatic induction of mRNA of the small 25 amino acid peptide hepcidin. Hepcidin has been hypothesized to be the mediator of iron- and inflammation-induced changes in iron metabolism. The molecular details of the connection between iron metabolism, hepcidin and inflammation have become clearer with the recent finding of hepcidin-induced internalization and degradation of FPN1. The work presented here demonstrates that the lipopolysaccharide-induced splenic macrophage FPN1 mRNA downregulation is not dependent upon the action of a single cytokine such as IL-6, IL-1 or TNF-alpha because mice deficient in these pathways downregulate FPN1 normally. Furthermore, hepcidin is also synthesized in the spleen of normal mice and induced by lipopolysaccharide. Additionally, in vitro, splenic adherent cells produce hepcidin in response to lipopolysaccharide in an IL-6-dependent manner. There appear to be both probable transcriptional and post-transcriptional control of FPN1 expression by lipopolysaccharide-induced inflammation. The former effect is on mRNA expression and is independent of hepcidin, whereas the latter is IL-6- and hepcidin-dependent.

Functional consequences of ferroportin 1 mutations

The cellular iron exporter ferroportin 1 is expressed in both the duodenum and in cells of the mononuclear phagocyte system. Expression of ferroportin 1 protein on the cell surface is regulated by the interaction of ferroportin 1 with hepcidin. Hepcidin treatment of cells results in internalization and lysosomal degradation of cell surface ferroportin 1. Recently, ferroportin 1 mutations leading to hemochromatosis (HFE4) have been identified. HFE4 differs from classical hemochromatosis in that there is a greater amount of macrophage iron sequestration. The data presented here demonstrate that HFE4 mutations are heterogeneous in their effects on protein function. Some mutations result in loss of function with partial protein sequestration in the ER. Others are indistinguishable from native ferroportin 1 and have a similar ability to deplete transfected cells of iron as evidenced by activation of the iron-response proteins and cellular ferritin depletion. Significantly, all mutants appear to be unresponsive to hepcidin and do not demonstrate the expected internalization on exposure to hepcidin. The clinical phenotypes observed in patients may be secondary to cell-type-specific defects in hepcidin-mediated inhibition of ferroportin 1 expression.

Changes in subcellular localization of metabotropic glutamate receptor subtypes during postnatal development of mouse thalamus

High resolution immunoelectron microscopy was used to study subcellular localization patterns of three metabotropic glutamate receptor subtypes (mGluR1alpha, mGluR5, and mGluR2/3) during postnatal development of mouse ventral posterior (VP) thalamic nucleus. Immunoreactivity for all three mGluRs was detected from birth (postnatal day 0, P0), but mGluR1alpha showed dramatic changes in localization with age. In the first postnatal week, mGluR1alpha immunoreactivity was mainly found in proximal dendrites and somata and not usually associated with synaptic contacts. From the second postnatal week, it became concentrated in distal dendrites and preferentially associated with corticothalamic (RS) synapses. mGluR5 immunoreactivity was weaker than mGluR1alpha immunoreactivity at all postnatal ages and showed a similar change in subcellular distribution to that of mGluR1alpha. It was also localized in astrocytic processes. mGluR2/3 immunoreactivity was mainly localized in astrocytic processes surrounding neuronal somata and synapses and this pattern was consistently maintained through all postnatal ages. A small number of presynaptic axon terminals were labeled for mGluR2/3 immunoreactivity and formed asymmetrical synapses. This study demonstrates that Group I mGluR proteins (mGluR1alpha and mGluR5) become redistributed in association with the development of corticothalamic function as demonstrated physiologically, whereas Group II mGluR proteins (mGluR2/3) are mainly associated with neuroglia.

Meta-analysis of pancreaticogastrostomy versus pancreaticojejunostomy after pancreaticoduodenectomy

BACKGROUND

Surgical reconstruction following pancreaticoduodenectomy (PD) is associated with significant morbidity and mortality. Because of great variability in definitions of specific complications, it remains unclear whether there is a difference in complication rates following the two commonest types of reconstruction, pancreaticogastrostomy (PG) and pancreaticojejunostomy (PJ). Published consensus definitions for postoperative pancreatic fistula (POPF) have led to a series of randomized clinical trials (RCTs) uniquely placed to address this question.

METHODS

A literature search was carried out to identify all RCTs comparing postoperative complications of PG versus PJ reconstruction following PD published between January 1995 and December 2013. Pooled odds ratios (ORs) with 95 percent confidence intervals (c.i.) were calculated using fixed-effect or random-effects models.

RESULTS

In total, seven RCTs with 1121 patients were included. Four of these trials applied definitions as published by the International Study Group on Pancreatic Fistula (ISGPF). Using ISGPF definitions, the incidence of POPF was lower in patients undergoing PG than in those having PJ (OR 0·50, 95 per cent c.i. 0·34 to 0·73; P < 0·001). Using definitions applied by each individual study, PG was associated with significantly lower rates of POPF (OR 0·51, 0·36 to 0·71; P < 0·001), intra-abdominal fluid collection (OR 0·50, 0·34 to 0·74; P < 0·001) and biliary fistula (OR 0·42, 0·18 to 0·93; P = 0·03) than PJ.

CONCLUSION

Meta-analysis of four RCTs based on ISGPF criteria, and seven RCTs using non-standard criteria, revealed that PG reduced the incidence of POPF after PD compared with PJ.

Post-transplant endothelial progenitor cell mobilization via CXCL10/CXCR3 signaling promotes liver tumor growth

BACKGROUND & AIMS

Patients with hepatocellular carcinoma (HCC) receiving living donor liver transplantation appear to possess significantly higher tumor recurrence than the recipients receiving deceased donor liver transplantation. The underlying mechanism for HCC recurrence after transplantation remains unclear. Here, we aim to investigate the impact of small-for-size liver graft injury on HCC recurrence after transplantation.

METHODS

The correlation between tumor recurrence, liver graft injury, CXCL10 expression and endothelial progenitor cell (EPC) mobilization was studied in 115 liver transplant recipients and rat orthotopic liver transplantation (OLT) models. The direct role of CXCL10/CXCR3 signaling on EPC mobilization was investigated in CXCL10(-/-) mice and CXCR3(-/-) mice. The role of EPCs on tumor growth and angiogenesis was further investigated in an orthotopic liver tumor model.

RESULTS

Clinically, patients with small-for-size liver grafts (<60% of standard liver weight, SLW) had significantly higher HCC recurrence (p=0.04), accompanied by more circulating EPCs and higher early-phase intragraft and plasma CXCL10 levels, than the recipients with large grafts (≥60% of SLW), which were further validated in rat OLT models. Circulatory EPC mobilization was reduced after liver injury both in CXCL10(-/-) mice and CXCR3(-/-) mice in comparison to wild-type controls. CXCL10 recruited EPCs in dose-dependent and CXCR3-dependent manners in vitro. Early-phase EPC/CXCL10 injection enhanced orthotopic liver tumor growth, angiogenesis and metastasis in nude mice.

CONCLUSIONS

Post-transplant enhanced CXCL10/CXCR3 signaling in small-for-size liver grafts directly induced EPC mobilization, differentiation and neovessel formation, which further promotes tumor growth. Targeting CXCL10/CXCR3 signaling may attenuate early-phase liver graft injury and prevent late-phase tumor recurrence/metastasis after transplantation.

Corticotropin-releasing factor is preferentially colocalized with excitatory rather than inhibitory amino acids in axon terminals in the peri-locus coeruleus region

Corticotropin-releasing factor(CRF)-immunoreactive terminals form synaptic specializations with locus coeruleus (LC) dendrites in rat brain. Within these terminals, CRF-immunoreactive dense core vesicles are colocalized with non-labeled dense core vesicles and clear vesicles, implicating other neuromodulators in the actions of CRF on LC neurons. Excitatory (glutamate) and inhibitory (GABA) amino acid afferents to the LC, have been identified which regulate noradrenergic responses to sensory stimuli. This study was designed to determine whether these amino acid neurotransmitters are colocalized with CRF in terminals within the LC/peri-LC region in the rat. Sections through the LC region that were dually labeled using immunohistochemical techniques to visualize either CRF and glutamate or CRF and GABA were examined using electron microscopy. Numerous terminals that contained immunolabeling for both CRF and glutamate (e.g. 30% of 106 CRF-immunoreactive terminals and 13% of 232 glutamate-immunolabeled terminals) were observed in the peri-LC. Additionally, single labeled CRF and glutamate terminals were often apposed to one another or found to converge on common dendritic targets. In contrast, relatively few terminals exhibited immunolabeling for both GABA and CRF (5% of 317 CRF-immunoreactive terminals). However, evidence for a postsynaptic effect of CRF on GABA-containing profiles included synapses between CRF axon terminals and GABA-labeled dendrites (10% of 317 CRF-labeled terminals), as well as appositions between CRF- and GABA-labeled terminals. These results indicate that CRF is preferentially colocalized with glutamate in the rostrolateral LC region and may impact on glutamate neurotransmission in the LC via presynaptic or postsynaptic actions. They argue against colocalization of CRF with GABA, although CRF may modulate GABA release via postsynaptic effects in the peri-LC region.

Systematic review and meta-analysis of outcomes after intraoperative pancreatic duct stent placement during pancreaticoduodenectomy

BACKGROUND

Postoperative pancreatic leakage after pancreaticoduodenectomy is often serious. Although some studies have suggested that stenting the anastomosis can reduce the incidence of this complication, the value of stenting in the setting of pancreaticoduodenectomy remains unclear.

METHODS

Studies comparing outcomes of stent versus no stent, and internal versus external stent placement for pancreaticoduodenectomy were eligible for inclusion. Pooled odds ratios (ORs) with 95 per cent confidence intervals were calculated using fixed- or random-effects models.

RESULTS

From a search of the literature published between January 1973 and September 2011, five randomized clinical trials (RCTs) and 11 non-randomized observational clinical studies (OCS) involving 1726 patients were selected for inclusion in this review. Meta-analysis of RCTs revealed that placing a stent in the pancreatic duct did not reduce the incidence of postoperative pancreatic fistula. External stents had no advantage over internal stents in terms of clinical outcome. Subgroup analyses revealed that use of an external stent significantly reduced the incidence of pancreatic fistula (RCTs: OR 0·42, 0·24 to 0·76, P = 0·004; OCS: OR 0·43, 0·27 to 0·68, P < 0·001), delayed gastric emptying (RCTs: OR 0·41, 0·19 to 0·87, P = 0·02) and postoperative morbidity (RCTs: OR 0·55, 0·34 to 0·89, P = 0·02) compared with no stent.

CONCLUSION

Pancreatic duct stenting did not reduce the incidence of pancreatic fistula and other complications in pancreaticoduodenectomy compared with no stenting. Although no difference was found between external and internal stents in terms of efficacy, external stents seemed to reduce the incidence of pancreatic fistula compared with control.

Evidence for coexistence of enkephalin and glutamate in axon terminals and cellular sites for functional interactions of their receptors in the rat locus coeruleus

The authors previously showed that a subset of axon terminals in the locus coeruleus (LC) contains methionine5-enkephalin (ENK) and gamma-aminobutyric acid (GABA) immunoreactivities. However, numerous ENK-labeled terminals lacked GABA and exhibited synaptic specializations that were characteristic of excitatory-type transmitters. To determine whether ENK coexists with glutamate in the LC, preembedding immunoperoxidase detection of ENK or immunogold-silver was combined with postembedding identification of glutamate using a gold marker. Indeed, 28% of the ENK-labeled axon terminals examined (n = 250 axon terminals) also contained glutamate. To define further sites for functional interactions between opiate ligands and excitatory amino acid receptors, the ultrastructural localization of the mu-opioid receptor (MOR) was examined with respect to either the kainate receptor (KAR) or the R1 subunit of the N-methyl-D-aspartate (NR1)-type glutamate receptor in the LC. Gold-silver labeling for MOR and peroxidase labeling for either KAR or NR1 indicated that the MOR often was localized to the plasma membrane of dendrites that also exhibited immunolabeling for either glutamate receptor subtype. In contrast to the KAR, which was identified primarily in somata and dendrites, NR1 immunoreactivity also was found frequently in axon terminals as well as in glial processes. Glial processes containing NR1 occasionally exhibited immunolabeling for MOR and sometimes were directly apposed to MOR-containing dendrites in the LC. Furthermore, NR1-labeled receptors in axon terminals sometimes were presynaptic to MOR-labeled dendrites. The authors concluded that ENK and glutamate may be cotransmitters in LC afferents. Moreover, ligands at the KAR may modulate directly MOR-containing neurons in the LC, whereas actions at NR1 receptors may affect opioid-sensitive neurons through multiple cellular mechanisms, i.e., through presynaptic, postsynaptic, or glial actions.

Subcellular distribution of AMPA and NMDA receptor subunit immunoreactivity in ventral posterior and reticular nuclei of rat and cat thalamus

Alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) and N-methyl-D-aspartate (NMDA) selective glutamate receptors mediate excitatory neurotransmission in the somatosensory thalamus, but morphological localization of the receptors at identified thalamic synapses has been lacking. The authors used electron microscopic immunocytochemistry to localize AMPA selective GluR 2/3 subunits (GluR2/3) and NMDA receptor subunit 1 (NMDAR1) in rat and cat ventral posterior lateral nucleus (VPL) and in the associated sector of the reticular nucleus (RTN). Light microscopy showed that GluR2/3 and NMDAR1 immunolabeled neurons are homogeneously distributed in both nuclei. The relationship between glutamate receptor labeled profiles and glutamate or gamma-aminobutyric acid (GABA) labeled synapses was revealed by combining preembedding and postembedding immunostaining at the electron microscopic level. GluR2/3 and NMDAR1 immunoreactivity was located in somata and in proximal and distal dendrites of VPL relay cells and of RTN cells. Immunoreactivity was concentrated in postsynaptic densities of glutamatergic synapses and absent from postsynaptic densities of GABAergic synapses. In the cat, GluR2/3 and NMDAR1 immunoreactivity was also localized in GABAergic interneurons, including their presynaptic dendrites (PSD). Of the GluR2/3 and NMDAR1 labeled thalamic synapses observed, 10-29% were lemniscal (RL) type synapses in VPL; 60-70% were corticothalamic (RS) type synapses in the VPL and RTN. In the cat, 7-19% were identified as PSD profiles, and more NMDAR1 labeled PSD were found in the VPL than in the RTN. The main findings were as follows: 1) AMPA selective GluR2/3 and NMDAR1 share similar distribution patterns in the rat and cat somatosensory thalamus, 2) both glutamate receptors are likely to be colocalized at postsynaptic densities of both RL and RS synapses, and 3) localization of the glutamate receptor proteins in GABAergic dendrites in the cat thalamus indicates that glutamatergic transmission to GABAergic neurons is also mediated by both NMDA and non-NMDA receptors.

A method for fixation of previously fresh-frozen human adult and fetal brains that preserves histological quality and immunoreactivity

A method is described that enables fixation of previously fresh-frozen and stored adult and fetal human or animal brains. The method involves fixing during thawing under controlled, cryoprotected conditions and is compatible with good histological quality and the preservation of enzymatic activity and immunoreactivity of many neural antigens. It offers considerable advantages for the storage of large amounts of tissue from which multiple samples can be taken and processed under fixation and other conditions that can be optimized for a variety of methods, many of which may be incompatible if the whole brain is fixed in a single fixative prior to storage.

Local excision of the parotid gland in the treatment of Warthin's tumour

The results of local excision of Warthin's tumour in the parotid gland (n = 61) (resection of the tumour together with surrounding normal gland and associated lymph nodes) were compared with those of superficial parotidectomy (n = 88) for incidence of recurrence, duration of operation, and degree of facial deformity. A subgroup of patients in each group were tested for gustatory sweating (iodine starch test) and parotid function (quantitative scintigraphy). Local excision had the following advantages over superficial parotidectomy: shorter operating time, less risk of facial nerve damage, less facial deformity, lower incidence of Frey's syndrome, and better preservation of the function of the parotid gland.

An in vivo and in vitro assessment of the anti-inflammatory, antinociceptive, and immunomodulatory activities of Clematis terniflora DC. extract, participation of aurantiamide acetate

AIM

Clematis terniflora DC. has been widely used as a traditional Chinese medicine for the treatment of tonsillitis, rheumatoid arthritis, and prostatitis. Despite its widespread use in China, there are currently no studies systematically examined its therapeutic effects and mechanism of action. As such, the present study was conducted to evaluate the anti-inflammatory, antinociceptive, and immunomodulatory effects of C. terniflora DC. using rodent and cellular models.

METHODS

The anti-inflammatory properties of the 70% ethanol eluted fraction of the 70% ethanol extract of C. terniflora DC. (EECTD) were evaluated using the xylene-induced ear swelling test, the carrageenan-induced edema model, and the cotton pellet granuloma method. Its antinociceptive activities were determined using both the acetic acid-induced writhing test and the hot plate assay. In parallel, we conducted an in vitro assay in LPS-induced RAW264.7 cells to examine the anti-inflammatory effects of EECTD and its purified form, aurantiamide acetate (AA) on inhibition of nitric oxide (NO) and prostaglandin E2 (PGE2) release.

RESULTS

EECTD (300mg/kg) significantly reduced the number of writhing, extended the pain response latency, and suppressed xylene-induced ear swelling. Each EECTD treatment group also had significant inhibition of cotton granulation formation in addition to reduced carrageenan-induced paw edema. EECTD was also shown to alleviate signs of inflammation in histopathological paw sections. However, it had a less noticeable effect on mouse ear swelling in the delayed type hypersensitivity test. A purified compound was isolated from EECTD and its structure was identified as AA. In vitro experimental results showed that both EECTD and AA were able to significantly inhibit the release of pro-inflammatory cytokines NO and PGE2 on LPS-induced RAW264.7 cells.

CONCLUSION

These results suggest that EECTD has significant anti-inflammatory and antinociceptive activities, partially related to one of the active substances identified as AA. We hypothesize that these effects are related to its ability to inhibit the production of cytokines NO and PGE2. However, further work will be needed to determine its exact mechanism of action.

Hyperbranched polyurethane as a highly efficient toughener in epoxy thermosets with reaction-induced microphase separation

Improvements in the toughness and thermal properties without affecting other mechanical properties in the hyperbranched polyurethane modified epoxy were demonstrated.

Smoking and the development of Warthin's tumour of the parotid gland

The smoking history was surveyed in 160 consecutive patients with Warthin's tumour of the parotid gland in order to investigate the relationship between smoking and the development of this tumour. Two hundred cases of middle-aged or elderly normal persons and 163 consecutive patients with pleomorphic adenoma in the parotid gland served as controls. The percentage of smoking in patients with Warthin's tumour (96.3%) was much higher than that of middle-aged or elderly normal persons (25.5%) and in patients with pleomorphic adenoma (26.4%). Moreover, the amount of smoking was greater and the smoking history was longer in patients with Warthin's tumour. When the male and female patients were analysed respectively, the same result was shown. This case-control study suggests that smoking may be one of the aetiologic factors associated with the development of Warthin's tumour.

Distinct mechanism of small-for-size fatty liver graft injury--Wnt4 signaling activates hepatic stellate cells

In this study, we aimed to investigate the significance of hepatic stellate cells (HSCs) activation in small-for-size fatty liver graft injury and to explore the underlying molecular mechanism in a rat liver transplantation model. A rat orthotopic liver transplantation model using fatty grafts (40% of fatty changes) and cirrhotic recipients was applied. Intragraft gene expression profiles, ultrastructure features and HSCs activation were compared among the rats received different types of grafts (whole vs. small-for-size, normal vs. fatty). The distinct molecular signature of small-for-size fatty graft injury was identified by cDNA microarray screening and confirmed by RT-PCR detection. In vitro functional studies were further conducted to investigate the direct effect of specific molecular signature on HSCs activation. HSCs activation was predominantly present in small-for-size fatty grafts during the first 2 weeks after transplantation, and was strongly correlated with progressive hepatic sinusoidal damage and significant upregulation of intragraft Wnt4 signaling pathway. In vitro suppression of Wnt4 expression could inhibit HSC activation directly. In conclusion, upregulation of Wnt4 signaling led to direct HSC activation and subsequently induced small-for-size fatty liver grafts injury. Discovery of this distinct mechanism may lay the foundation for prophylactic treatment for marginal graft injury in living donor liver transplantation.

Controlling vibrational resonance in a multistable system by time delay

The phenomenon of vibrational resonance in a delayed multistable system that is excited by biharmonic signals is investigated in the present paper. Different from the former theory, the appearance and the disappearance of the vibrational resonance are controlled by adjusting the time delay parameter instead of modulating the amplitude of the high-frequency signal. The motion of the orbit within or between the different potential wells can also be controlled. Furthermore, based on both the methods of numerical simulation and analytical analysis, the behavior of delay-induced multiple vibrational resonance and its mechanism are investigated and discussed. The multiple vibrational resonance, which is quantified by the response amplitude at the low-frequency, is found to be periodic in the delay parameter with two periods, i.e., the periods of the two driven signals. The method used in this paper gives a new way for controlling vibrational resonance in a multistable system.

Endoplasmic reticulum chaperone prolyl 4-hydroxylase, beta polypeptide (P4HB) promotes malignant phenotypes in glioma via MAPK signaling

Endoplasmic reticulum (ER) chaperone Prolyl 4-hydroxylase, beta polypeptide (P4HB) has previously been identified as a novel target for chemoresistance in glioblastoma multiforme (GBM). Yet its functional roles in glioma carcinogenesis remain elusive. In clinical analysis using human glioma specimens and Gene Expression Omnibus (GEO) profiles, we found that aberrant expression of P4HB was correlated with high-grade malignancy and an angiogenic phenotype in glioma. Furthermore, P4HB upregulation conferred malignant characteristics including proliferation, invasion, migration and angiogenesis in vitro, and increased tumor growth in vivo via the mitogen-activated protein kinase (MAPK) signaling pathway. Pathway analysis suggested genetic and pharmacologic inhibition of P4HB suppressed MAPK expression and its downstream targets were involved in angiogenesis and invasion. This is the first study that demonstrates the oncogenic roles of P4HB and its underlying mechanism in glioma. Since tumor invasion and Vascularisation are typical hallmarks in malignant glioma, our findings uncover a promising anti-glioma mechanism through P4HB-mediated retardation of MAPK signal transduction.