RACK1, a potential target to decrease morphine reward in mice

Morphine reexposure induces the decrease of receptor for activated C-kinase 1 protein (RACK1) levels in frontal cortex, and the increase of p-ERK (extracellular signal-regulated kinase) levels in mouse frontal cortex, striatum, hippocampus and nucleus accumbens (NAcc). Moreover, RACK1 is associated with the core kinases of the ERK pathway, Raf, MEK, and ERK. The purpose of this study is to investigate the effect of overexpression of RACK1 on the conditioned place preference (CPP) and the level of p-ERK in morphine reexposure mice. Mice were subcutaneously injected with morphine on the 2nd, 4th, 6th, and the 8th day, saline was delivered the next day. After mice showed place preference, RACK1 was administered by intraventricular injection 20 minutes after injection of morphine on the 11th, 13th, 15th, and 17th day. CPP was measured on the 18th day. It was found that morphine reexposured mice showed a decreased RACK1 level in the frontal cortex, striatum and an increased RACK1 level in hippocampus and NAcc, but this effect was reversed after administration of RACK1. In this study we demonstrated that RACK1 decreased p-ERK and erased CPP during reexposure of morphine and there was no an effect in reexposure saline mice. It strongly suggests that RACK1 may play a crucial role in morphine reexposured mice and the RACK1 has the potential to be a remedy to the morphine reward.

Runx2, osx, and dspp in tooth development

The transcription factors Runx2 and Osx are necessary for osteoblast and odontoblast differentiation, while Dspp is important for odontoblast differentiation. The relationship among Runx2, Osx, and Dspp during tooth and craniofacial bone development remains unknown. In this study, we hypothesized that the roles of Runx2 and Osx in the regulation of osteoblast and odontoblast lineages may be independent of one another. The results showed that Runx2 expression overlapped with Osx in dental and osteogenic mesenchyme from E12 to E16. At the later stages, from E18 to PN14, Runx2 and Osx expressions remained intense in alveolar bone osteoblasts. However, Runx2 expression was down-regulated, whereas Osx expression was clearly seen in odontoblasts. At later stages, Dspp transcription was weakly present in osteoblasts, but strong in odontoblasts where Osx was highly expressed. In mouse odontoblast-like cells, Osx overexpression increased Dspp transcription. Analysis of these data suggests differential biological functions of Runx2, Osx, and Dspp during odontogenesis and osteogenesis.

Abundantly expressed hepatic genes and their differential expression in liver of prelaying and laying geese

Geese have a short egg-laying period and a low egg production rate. To induce and maintain egg laying, genes related to generating hepatic lipid for yolk deposition should be adequately expressed. Liver mRNA from 6 laying geese was extracted and used for construction of a full-length enriched cDNA library. About 2,400 clones containing gene sequences were determined and National Center for Biotechnology Information Gallus gallus Gene Index databases were used to compare and analyze these sequences. Ten highly expressed genes were selected to determine the differential expression between laying and prelay goose liver. Tissue distribution data showed that very low density apolipoprotein II, liver type fatty acid binding protein, vitellogenin I, and vitellogenin II transcripts were specifically expressed in the liver of laying geese. Ovoinhibitor, preproalbumin, alpha-2-hs-glycoprotein, and vitamin D binding protein mRNA were highly expressed in the liver and to a lesser extent in other tissues. Ovotransferrin mRNA was expressed in liver, ovary, oviduct, shell gland, brain, and adipose tissues. The concentration of transthyretin mRNA was high in the liver and brain. The mRNA concentrations of liver type fatty acid binding protein, alpha-2-hs-glycoprotein, and transthyretin in the livers of laying and prelay geese were not different. The concentrations of hepatic ovotransferrin, ovoinhibitor, preproalbumin, very low density apolipoprotein II, vitellogenin I, vitellogenin II, and vitamin D binding protein mRNA were higher in the liver of laying geese than in prelay geese, suggesting that these genes may be involved in laying function or lipid metabolism related to egg formation.

Brushing effects on the growth and mechanical properties of Corispermum mongolicum vary with water regime

High water availability and mechanical stress can induce opposite responses in plants. In arid areas of Northern China the occurrence of high wind and high water availability tend to be negatively correlated. Since turgor pressure is a determinant of the mechanical stability of annuals, it is hypothesised that the effects of mechanical perturbation (MP) on annuals may depend on soil water availability. To test this proposal, we conducted an experiment in which a pioneering annual Corispermum mongolicum was subjected to two levels of MP and water supply, and then determined its growth and mechanical traits. Brushing had no effect on plant height and total biomass, but stimulated leaf and branch production. Water supply affected plant height, basal diameter, total biomass and stem rigidity, but not leaf and branch number, root/shoot ratio or flexibility. With high water availability, brushing stimulated the production of stiffer stems (thicker and with a higher Young's modulus) and more roots relative to shoot mass, but with low water availability MP induced the opposite response. This shows that both the degree and direction of plant responses to MP depend on the presence of other factors. We discuss how the interactive effects of MP and water availability on growth and mechanical properties may help C. mongolicum to establish in windy and arid environments.

A comparison of two rehabilitation protocols after simultaneous bilateral total knee arthroplasty: a controlled, randomized study

Post-operative outcomes after simultaneous bilateral total knee arthroplasty in 115 patients randomly assigned to two rehabilitation protocols were compared. The traditional-protocol group performed a series of exercises on one leg and then repeated the same sequence on the other leg. The alternate-protocol group performed the same exercises, but alternated between legs with each individual repetition. Symptoms and function were assessed pre-operatively and at 1, 3, 6 and 12 months post-operatively. The alternate-protocol group had lower visual analogue pain scale scores in the early post-operative period, as well as higher Knee Society Scores and SF-12 physical and mental health summary scores after 1 and 3 months compared with the traditional-protocol group, but there were no differences between the two groups from 6 months post-operatively. There were no significant differences between the groups in terms of range of knee motion or incidence of deep vein thrombosis. The alternate-protocol for rehabilitation resulted in an early return to function and decreased pain levels following simultaneous bilateral total knee arthroplasty and was associated with the potential to produce more positive emotional states and earlier functional independence.

Thymic stromal lymphopoietin, OX40-ligand, and interleukin-25 in allergic responses

Allergic diseases are often triggered by environmental allergens that induce dominant type 2 immune responses, characterized by the infiltrated T-helper type 2 (TH2) lymphocytes, eosinophils, and elevated TH2 cytokines. In addition to TH2 type immune responses, epithelial stress and injury linked to tissue remodelling are often observed, suggesting that epithelial cells may play important role in regulating allergic responses. Dendritic cells (DCs), the professional antigen-presenting cells with the capabilities of sampling allergens, are considered as the key player on instructing TH2 immune responses. Whether inflamed epithelium can regulate innate immunity, such as macrophages and DCs, which in turn instructs adaptive immunity has long been hypothesized. Studies of thymic stromal lymphopoietin (TSLP), an epithelial cells-derived cytokine, that can strongly activate DCs, provide important evidences that the epithelial barrier can trigger allergic diseases by regulating immune responses. The finding that OX40/OX40Ligand (OX40L) interactions are the molecular trigger responsible for the induction and maintenance of TH2 responses by TSLP-activated DCs provides a plausible molecular explanation for TSLP-mediated allergy. Recent progresses in characterizing the pro-inflammatory IL-17 cytokine family have added an additional layer of complexity on the regulation of allergic inflammation. TSLP-DCs can induce a robust expansion of TH2 memory cells and strengthen functional attributes by up-regulating their surface expression of IL-17RB (IL-25R), the receptor for cytokine IL-17E (IL-25), a distinct member of IL-17 cytokine family. IL-17E (also known as IL-25) produced by epithelial cells, and other innate cells, such as eosinphils, basophils, and mast cells, are shown to regulate adaptive immunity by enhancing TH2 cytokine productions. These exciting findings expand our knowledge of the complex immunological cascades that result in allergic inflammation and may provide novel therapeutic approaches for the treatment of allergic diseases.

Simvastatin increases osteoblasts and osteogenic proteins in ovariectomized rats

BACKGROUND

Previous reports have indicated that statins could prevent bone loss in ovariectomized (OVX) rats and increase the expressions of osteogenic genes in cultured osteoblasts. In this study, we hypothesized that simvastatin might increase osteoblast number and protein expressions of osteogenic markers localized in bones in concomitance with the prevention of bone loss in OVX rats.

MATERIALS AND METHODS

Fifty-four 3-month-old OVX and sham-operated (SHAM) female Sprague-Dawley rats were used. Simvastatin (10-20 mg kg(-1) day(-1)) was administrated orally for 6 weeks. Trabecular volume, osteoblast number and osteogenic proteins including BMP2, collagen type I and osteocalcin on bone sections obtained from lumbar vertebral body, distal femur and proximal tibia were measured.

RESULTS

The results showed that SHAM rats had significantly less trabecular bone volume and osteoblast number than that of OVX rats 6 weeks after operation. Oral simvastatin treatment (10-20 mg kg(-1) day(-1)) increased bone volume and osteoblast number in the distal femurs, proximal tibiae and vertebrae of OVX rats. Furthermore, the osteoblastic cells with immuno-stained BMP2, collagen type I and osteocalcin in vertebral bones were significantly increased by simvastatin treatment (20 mg kg(-1) day(-1)) in OVX rats.

CONCLUSIONS

This study demonstrates that simvastatin enhances the production of osteogenic proteins in bone and this effect may contribute to the prevention of bone loss in OVX rats.

Cellular behavior change of macrophage after exposure to nanoparticles

Magnetic nanoparticles (MNPs) are few of the nanoparticles used clinically. When MNPs are delivered into human body, they are ingested by macrophages. We evaluated the cellular response of macrophage after MNPs loading. In face of stimulation by lipopolysaccharide, a strong stimulant derived from bacterial cell wall, MNPs loaded macrophage exhibited decreased phagocytic activity and decreased generation of cytokines such as TNF-alpha, IL-1beta whereas increased nitric oxide generation was noticed. Although these changes might decrease bactiericidal activity, it also alleviates the risk of senses, a life threatening phenomenon in infection patients. The finding has significant implications on nanoparticle based targeted drug delivery.

Synthesis and characterization of core-shell structural MWNT-zirconia nanocomposites

Core-shell structural MWNT/ZrO2 nanocomposites were successfully prepared by one-step hydrolyzing of MWNT-dispersed ZrOCl2.8H2O aqueous solution. A highly conformal and uniform monoclinic zirconia coating was deposited on MWNTs by this new and simple method, and the thickness of the coating increased with the reaction time.

Gene expression patterns during intramuscular fat development in cattle

Deposition of intramuscular fat, or "marbling," in beef cattle contributes significantly to meat quality variables, including juiciness, flavor, and tenderness. The accumulation of intramuscular fat is largely influenced by the genetic background of cattle, as well as their age and nutrition. To identify genes that can be used as early biomarkers for the prediction of marbling capacity, we studied the muscle transcriptome of 2 cattle crossbreeds with contrasting intramuscular fat content. The transcriptomes of marbling LM tissue of heifers from Wagyu x Hereford (WxH; n = 6) and Piedmontese x Hereford (PxH; n = 7) crosses were profiled by using a combination of complementary DNA microarray and quantitative reverse transcription-PCR. Five biopsies of LM were taken from each animal at approximately 3, 7, 12, 20, and 25 mo from birth. Tissue was also collected from the LM of each animal at slaughter (approximately 30 mo). Microarray experiments, conducted on the first 3 biopsies of 2 animals from each crossbreed, identified 97 differentially expressed genes. The gene expression results indicated that the LM transcriptome of animals with high marbling potential (WxH) could be reliably distinguished from less marbled animals (PxH) when the animals were as young as 7 mo of age. At this early age, one cannot reliably determine meaningful differences in intramuscular fat deposition. We observed greater expression of a set of adipogenesis- and lipogenesis-related genes in the LM of young WxH animals compared with their PxH contemporaries. In contrast, genes highly expressed in PxH animals were associated with mitochondrial oxidative activity. Further quantitative reverse transcription-PCR experiments revealed that the messenger RNA of 6 of the lipogenesis-related genes also peaked at the age of 20 to 25 mo in WxH animals. The messenger RNA expression of ADIPOQ, SCD, and THRSP was highly correlated with intramuscular fat content of an individual in WxH animals. Our study provides clear evidence of early molecular changes associated with marbling and also identifies specific time frames when intramuscular fat development in cattle muscle can be detected by using gene expression. This information could be used by animal scientists to design optimal nutrition for high marbling potential. In addition, the genes found to be highly expressed during development of marbling could be used to develop genetic markers or biomarkers to assist with beef production strategies.

Induction treatment of proliferative lupus nephritis with leflunomide combined with prednisone: a prospective multi-centre observational study

To evaluate the efficacy and safety of leflunomide in the treatment of proliferative lupus nephritis, a prospective multi-centre observational study was conducted. Patients with biopsy proven proliferative lupus nephritis were assigned to receive either leflunomide or cyclophosphamide with concomitant prednisone. Leflunomide was given orally with a loading dose of 1 mg/kg/day for 3 days followed by 30 mg/day. Intravenous cyclophosphamide was administered monthly at a dose of 0.5 g/m2 of body-surface area. A total of 110 patients were enrolled, 70 in the leflunomide group and 40 in the cyclophosphamide group. The complete remission rate in the leflunomide group was 21% and partial remission rate 52%, as compared with 18% and 55%, respectively, in the cyclophosphamide group. Renal parameters and systemic lupus erythematosus disease activity index improved significantly and similarly in both groups. Serum creatinine decreased or stabilized in both treatment groups. No significant difference was noted with respect to clinical outcome between groups. Repeat biopsy also showed a significant reduction of active lesions in kidney pathology after 6 months of leflunomide treatment. Major adverse events, similar in both treatment groups, included infection, alopecia and hypertension. Leflunomide, compared with cyclophosphamide, in combination with prednisone was effective in the induction therapy of proliferative lupus nephritis and was generally well-tolerated.

Anti-inflammatory effects of dimemorfan on inflammatory cells and LPS-induced endotoxin shock in mice

BACKGROUND AND PURPOSE

Dimemorfan (a sigma1 receptor agonist) showed neuroprotective properties in animal models of inflammation-mediated neurodegenerative conditions, but its effects on inflammatory cells and systemic inflammation remain unclear.

EXPERIMENTAL APPROACH

The effects of dimemorfan on phorbol-12-myristate-13-acetate (PMA)- and N-formyl-methionyl-leucyl-phenylalanine (fMLP)- induced neutrophils and lipopolysaccharide (LPS)-activated microglial cells, as well as LPS-induced endotoxin shock in mice were elucidated.

KEY RESULTS

Dimemorfan decreased PMA- and fMLP-induced production of reactive oxygen species (ROS) and CD11b expression in neutrophils, through mechanisms independent of sigma1 receptors, possibly by blocking ROS production and G-protein-mediated intracellular calcium increase. Dimemorfan also inhibited LPS-induced ROS and nitric oxide (NO) production, as well as that of monocyte chemoattractant protein-1 and tumour necrosis factor-alpha (TNF-alpha), by inhibition of NADPH oxidase (NOX) activity and suppression of iNOS up-regulation through interfering with nuclear factor kappa-B (NF-kappaB) signalling in microglial cells. Treatment in vivo with dimemorfan (1 and 5 mg kg(-1), i.p., at three successive times after LPS) decreased plasma TNF-alpha, and neutrophil infiltration and oxidative stress in the lung and liver.

CONCLUSIONS AND IMPLICATIONS

Our results suggest that dimemorfan acts via sigma1 receptor-independent mechanisms to modulate intracellular calcium increase, NOX activity, and NF-kappaB signalling, resulting in inhibition of iNOS expression and NO production, and production of pro-inflammatory cytokines. These effects may contribute its anti-inflammatory action and protective effects against endotoxin shock in mice.

Inhibition of the rapid component of the delayed rectifier potassium current in ventricular myocytes by angiotensin II via the AT1 receptor

BACKGROUND AND PURPOSE

There is increasing evidence that angiotensin II (Ang II) is associated with the occurrence of ventricular arrhythmias. However, little is known about the electrophysiological effects of Ang II on ventricular repolarization. The rapid component of the delayed rectifier K(+) current (I(Kr)) plays a critical role in cardiac repolarization. Hence, the aim of this study was to assess the effect of Ang II on I(Kr) in guinea-pig ventricular myocytes.

EXPERIMENTAL APPROACH

The whole-cell patch-clamp technique was used to record I(Kr) in native cardiocytes and in human embryonic kidney (HEK) 293 cells, co-transfected with human ether-a-go-go-related gene (hERG) encoding the alpha-subunit of I(Kr) and the human Ang II type 1 (AT(1)) receptor gene.

KEY RESULTS

Ang II decreased the amplitude of I(Kr) in a concentration-dependent manner with an IC(50) of 8.9 nM. Action potential durations at 50% (APD(50)) and 90% (APD(90)) repolarization were prolonged 20% and 16%, respectively by Ang II (100 nM). Ang II-induced inhibition of the I(Kr) was abolished by the AT(1) receptor blocker, losartan (1 muM). Ang II decreased hERG current in HEK293 cells and significantly delayed channel activation, deactivation and recovery from inactivation. Moreover, PKC inhibitors, stausporine and Bis-1, significantly attenuated Ang II-induced inhibition of I(Kr).

CONCLUSIONS AND IMPLICATIONS

Ang II produces an inhibitory effect on I(Kr)/hERG currents via AT(1) receptors linked to the PKC pathway in ventricular myocytes. This is a potential mechanism by which elevated levels of Ang II are involved in the occurrence of arrhythmias in cardiac hypertrophy and failure.

Serotonin receptor 1B (HTR1B) genotype associated with milk production traits in cattle

Serotonin receptor 1B (HTR1B) is one of the 14 different identified serotonin receptors which are involved in the regulation of behaviors such as sleep, fear, aggression, mood, and feeding. The aims of this study were to characterize polymorphisms in the 5' coding and the 3' flanking regions of the bovine HTR1B gene among Chinese Holsteins and to identify the association of HTR1B polymorphisms with milk production performance. SSCP was used to examine the polymorphisms at four loci and the fragments with different SSCP patterns were sequenced. A total of three single nucleotide polymorphisms (SNPs) were detected, among which the 205G>T mutation was found to cause a predicted amino acid change: from Ala to Ser at position 69. The polymorphism of G205T was identified to be associated with milk yield trait. Furthermore, the H1-C genotype was found to be associated with a significant increase in milk yield of 489kg vs. the H1-A genotype (P<0.05).

Urocortins and cholecystokinin-8 act synergistically to increase satiation in lean but not obese mice: involvement of corticotropin-releasing factor receptor-2 pathway

Interactions between gastrointestinal signals are a part of integrated systems regulating food intake (FI). We investigated whether cholecystokinin (CCK)-8 and urocortin systems potentiate each other to inhibit FI and gastric emptying (GE) in fasted mice. Urocortin 1 and urocortin 2 (1 microg/kg) were injected ip alone or with CCK (3 microg/kg) in lean, diet-induced obese (DIO) or corticotropin-releasing factor receptor-2 (CRF(2))-deficient mice. Gastric vagal afferent activity was recorded from a rat stomach-vagus in vitro preparation. When injected separately, urocortin 1, urocortin 2, or CCK did not modify the 4-h cumulative FI in lean mice. However, CCK plus urocortin 1 or CCK plus urocortin 2 decreased significantly the 4-h FI by 39 and 27%, respectively, compared with the vehicle + vehicle group in lean mice but not in DIO mice. Likewise, CCK-urocortin-1 delayed GE in lean but not DIO mice, whereas either peptide injected alone at the same dose had no effect. CCK-urocortin 2 suppression of FI was observed in wild-type but not CRF(2)-deficient mice. Gastric vagal afferent activity was increased by intragastric artery injection of urocortin 2 after CCK at a subthreshold dose, and the response was reversed by devazepide. These data establish a peripheral synergistic interaction between CCK and urocortin 1 or urocortin 2 to suppress FI and GE through CRF(2) receptor in lean mice that may involve CCK modulation of gastric vagal afferent responsiveness to urocortin 2. Such synergy is lost in DIO mice, suggesting a resistance to the satiety signaling that may contribute to maintain obesity.

Human mesenchymal stromal cells ameliorate the phenotype of SOD1-G93A ALS mice

BACKGROUND

Amyotrophic lateral sclerosis (ALS) is a progressive, lethal, neurodegenerative disease, currently without any effective therapy. Multiple advantages make mesenchymal stromal cells (MSC) a good candidate for cellular therapy in many intractable diseases such as stroke and brain injury. Until now, no irrefutable evidence exists regarding the outcome of MSC transplantation in the mouse model of ALS. The present study was designed to investigate the therapeutic potential of human MSC (hMSC) in the mouse model of ALS (SOD1-G93A mice).

METHODS

hMSC were isolated from iliac crest aspirates from healthy donors and kept in cell cultures. hMSC of the fifth passage were delivered intravenously into irradiated pre-symptomatic SOD1-G93A mice. Therapeutic effects were analyzed by survival analysis, rotarod test, motor neuron count in spinal cord and electrophysiology. The engraftment and in vivo differentiation of hMSC were examined in the brain and spinal cord of hMSC-transplanted mice.

RESULTS

After intravenous injection into irradiated pre-symptomatic SOD1-G93A mice, hMSC survived more than 20 weeks in recipient mice, migrated into the parenchyma of brain and spinal cord and showed neuroglia differentiation. Moreover, hMSC-transplanted mice showed significantly delayed disease onset (14 days), increased lifespan (18 days) and delayed disease progression compared with untreated mice.

DISCUSSION

Our data document the positive effects of hMSC transplantation in the mouse model of ALS. It may signify the potential use of hMSC in treatment of ALS.

Optimization of fermentation condition for antibiotic production by Xenorhabdus nematophila with response surface methodology

AIMS

To evaluate the influence of environmental parameters on the production of antibiotics (xenocoumacins and nematophin) by Xenorhabdus nematophila and enhance the antibiotic activity.

METHODS AND RESULTS

Response surface methodology (RSM) was employed to study the effects of five parameters (the initial pH, medium volume in flask, rotary speed, temperature and inoculation volume) on the production of antibiotics in flask cultures by X. nematophila YL001. A 2(5-1)-factorial central composite design was chosen to explain the combined effects of the five parameters and to design a minimum number of experiments. The experimental results and software-predicted values of production of antibiotics were comparable. The statistical analysis of the results showed that, in the range studied, medium volume in flask, rotary speed, temperature and inoculation volume had a significant effect (P < 0.05) on the production of antibiotics at their individual level, medium volume in flask and rotary speed showed a significant influence at interactive level and were most significant at individual level. The maximum antibiotic activity was achieved at the initial pH 7.64, medium volume in 250 ml flask 25 ml, rotary speed of 220 rev min(-1), temperature 27.8 degrees C and inoculation volume of 15.0%. Maximum antibiotic activity of 331.7 U ml(-1) was achieved under the optimized condition.

CONCLUSIONS

As far as known, there are no reports of production of antibiotic from X. nematophila by engineering the condition of fermentation using RSM. The results strongly support the use of RSM for fermentation condition optimization. The optimization of the environmental parameters resulted not only in a 43.4% higher antibiotic activity than unoptimized conditions but also in a reduced amount of the experiments. The chosen method of optimization of fermentation condition was efficient, relatively simple and time and material saving.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study should contribute towards improving the antibiotics activity of X. nematophila. Integrated into a broader study of the impact of environmental factors on the production of antibiotic, this work should help to build more rational control strategy, possibly involving scale-up of production of antibiotics by X. nematophila.

Effects and mediated pathway of electrical stimulation of nucleus ambiguus on gastric motility and mucus secretion in rats

BACKGROUND

It has been reported that nucleus ambiguus (NA) can regulate gastric motility. However, gastric motility is enhanced or inhibited after NA is excited, and reports have been inconsistent. Does NA affect gastric mucus secretion? This has been unreported up to now. We researched the effects of electrical stimulation of NA on gastric motility and mucus secretion in rats.

MATERIAL AND METHODS

The rats were divided into three groups. Group I, right NA was stimulated by four stimulation parameters. Group II, left NA was stimulated by the same parameters. The four stimulation parameters were 30 Hz 0.15 mA, 30 Hz 0.20 mA, 40 Hz 0.15 mA and 40 Hz 0.20 mA, and the width of all stimulation pulses was 0.30 ms. Group III, right NA was stimulated after the vagus nerves beneath the diaphragm were cut.

RESULTS

Electrical stimulations of both NAs significantly inhibited gastric motility, the right NA more so than the left. The results for group III show that the inhibitory effect of NA on gastric motility was withdrawn by vagotomy beneath the diaphragm.

CONCLUSIONS

NA inhibits gastric motility and the inhibitory degree of right NA is more than that of left NA. The inhibitory effect is mediated by vagus nerves. However, NA has no effect on gastric mucus secretion.

Gene expression profiling of muscle tissue in Brahman steers during nutritional restriction

Expression profiling using microarrays allows for the detailed characterization of the gene networks that regulate an animal's response to environmental stresses. During nutritional restriction, processes such as protein turnover, connective tissue remodeling, and muscle atrophy take place in the skeletal muscle of the animal. These processes and their regulation are of interest in the context of managing livestock for optimal production efficiency and product quality. Here we expand on recent research applying complementary DNA (cDNA) microarray technology to the study of the effect of nutritional restriction on bovine skeletal muscle. Using a custom cDNA microarray of 9,274 probes from cattle muscle and s.c. fat libraries, we examined the differential gene expression profile of the LM from 10 Brahman steers under three different dietary treatments. The statistical approach was based on mixed-model ANOVA and model-based clustering of the BLUP solutions for the gene x diet interaction effect. From the results, we defined a transcript profile of 156 differentially expressed array elements between the weight loss and weight gain diet substrates. After sequence and annotation analyses, the 57 upregulated elements represented 29 unique genes, and the 99 downregulated elements represented 28 unique genes. Most of these co-regulated genes cluster into groups with distinct biological function related to protein turnover and cytoskeletal metabolism and contribute to our mechanistic understanding of the processes associated with remodeling of muscle tissue in response to nutritional stress.

Cross-linking organic semiconducting molecules by preferential C-H cleavage via “chemistry with a tiny hammer”

In the context of collision-induced dissociation in chemistry and kinematics in physics, we have determined that a beam of hyperthermal protons can be used as tiny hammers to preferentially break the C-H bonds of hydrocarbon precursor molecules adsorbed on a conductive substrate with little damage to other chemical bonds. The activated molecules are thereby converted to a cross-linked molecular network, with its chemical properties tailored by the preservation of the chemical functional groups of the precursors and with its physical properties tuned by the degree of cross-linking. This “chemistry with a tiny hammer” process is adopted to induce inter-chain cross-linking of the semiconducting molecular chains in poly (3,4-ethylenedioxythiophene) molecular films and to raise the electrical conductivity and stability of the molecular films. The results exemplify the unusual reaction design of this process as well as its application in electronic and optoelectronic device fabrication. The application is particularly attractive because the process does not require any chemical additives or catalysts other than a beam of protons, and it needs no thermal budget.Key words: organic semiconductor, polymeric semiconductor, cross-linking, polymer, collision, dissociative collision, molecular electronics, device fabrication.

Stilbene C-glucosides from Cissus repens

Four new stilbene C-glucosides, namely trans-3-O-methyl-resveratrol-2-C-beta-glucoside (1), cis-3-O-methyl-resveratrol-2-C-beta-glucoside (2), trans-3-O-methyl-resveratrol-2-(2-p-coumaric)-C-beta-glucoside (cissuside A) (3), and trans-3-O-methyl-resveratrol-2-(3-p-coumaric)-C-beta-glucoside (cissuside B) (4), were isolated from the aerial parts of Cissus repens, along with known trans-resveratrol (5), trans-resveratrol-2-C-beta-glucoside (6) and cis-resveratrol-2-C-beta-glucoside (7). Their structures were established by spectroscopic methods. Stilbene C-glucosides were found in the genus Cissus for the first time.

Intra-articular injection of the cyclooxygenase-2 inhibitor parecoxib attenuates osteoarthritis progression in anterior cruciate ligament-transected knee in rats: role of excitatory amino acids

OBJECTIVE

Our present study examined the effect of intra-articular cyclooxygenase-2 (COX-2) inhibitor parecoxib on osteoarthritis (OA) progression and the concomitant changes in excitatory amino acids' (EAAs) levels of the anterior cruciate ligament-transected (ACLT) knee joint dialysates.

METHODS

OA was induced in Wistar rats by anterior cruciate ligament transection of the knee of one hindlimb, the other was left unoperated and untreated. Rats were placed into four groups: Group ACLT/P received intra-articular parecoxib injection (100 microg) in the ACLT knee once a week for 5 consecutive weeks starting at 8 weeks after surgery. Group ACLT/S received the same procedure as group ACLT/P with saline injection instead. Naïve (Naïve/P) rats received only intra-articular parecoxib injection in one knee once a week for 5 consecutive weeks without surgery. The sham-operated rats underwent arthrotomy only without treatment. Twenty weeks after surgery, knee joint dialysates were collected and EAAs' concentration was assayed by high-performance liquid chromatography, and gross morphology and histopathology (Mankin and synovitis grading) were examined on the medial femoral condyles and synovia.

RESULTS

Parecoxib alone had no effect on cartilage and synovium of normal knees in Naïve/P rats. In ACLT/P rats, parecoxib treatment showed a significant inhibition of cartilage degeneration of the medial femoral condyle at both the macroscopic level (1.15+/-0.17 vs 2.55+/-0.12, P<0.05) and the Mankin scores (3.03+/-0.28 vs 8.82+/-0.43, P<0.05). Intra-articular parecoxib injection also suppressed the synovial inflammation of ACLT joint compared to the ACLT/S group (3.92+/-0.41 vs 9.25+/-0.32, P<0.05). Moreover, glutamate and aspartate levels were also significantly reduced in the ACLT/P group compared to the ACLT/S group by parecoxib treatment (91.2+/-9.4% vs 189.5+/-17.0%, P<0.05 and 98.2+/-11.6% vs 175.3+/-12.4%, P<0.05, respectively).

CONCLUSION

This study shows that intra-articular injection of COX-2 inhibitor parecoxib inhibits the ACLT-induced OA progression; it was accompanied by a reduction of glutamate and aspartate concentration in the ACLT joint dialysates. From our present results, we suggested that intra-articular parecoxib injection, in addition to the anti-inflammatory effect, inhibiting the EAAs' release, may also play a role in inhibiting the traumatic knee injury induced OA progression.

Cytochrome P450 3A5 genotype is associated with verapamil response in healthy subjects

We hypothesized that CYP3A5 genotype contributes to the interindividual variability in verapamil response. Healthy subjects (n=26) with predetermined CYP3A5 genotypes were categorized as expressers (at least one CYP3A5(*)1 allele) and nonexpressers (subjects without a CYP3A5(*)1 allele). Verapamil pharmacokinetics and pharmacodynamics were determined after 7 days of dosing with 240 mg daily. There was a significantly higher oral clearance of R-verapamil (165.1+/-86.4 versus 91.2+/-36.5 l/h; P=0.009) and S-verapamil (919.4+/-517.4 versus 460.2+/-239.7 l/h; P=0.01) in CYP3A5 expressers compared to nonexpressers. Consequently, CYP3A5 expressers had significantly less PR-interval prolongation (19.5+/-12.3 versus 44.0+/-19.4 ms; P=0.0004), and had higher diastolic blood pressure (69.2+/-7.5 versus 61.6+/-5.1 mm Hg; P=0.036) than CYP3A5 nonexpressers after 7 days dosing with verapamil. CYP3A5 expressers display a greater steady-state oral clearance of verapamil and may therefore experience diminished pharmacological effect of verapamil due to a greater steady state oral clearance.

Contrasting reactive oxygen species and transition metal concentrations in combustion aerosols

The presence of reactive oxygen species (ROS) and 10 transition metals (Ag, Cd, Co, Cu, Fe, Mn, Ni, Ti, V and Zn) in both the acid-soluble and water-soluble fractions of fine particles of combustion origin were determined. ROS was analyzed using the dichlorofluorescin fluorescence technique. Particles emitted from on-road vehicles, gas cooking, incense burning, and cigarette smoke were characterized along with those in the background air of outdoor and indoor environments. In addition, this study evaluated the possible relationships between ROS and individual transition metals. It is found that cigarette smoke which had the highest concentration of metals also contained the highest concentration of ROS. Regression analysis performed showed that water-soluble metals including Cd, Co, Cu, Fe, Mn, and Ni showed better correlation with ROS concentration as compared to acid-soluble (total) metals. The findings demonstrated that water-soluble metals could be one of the species influencing ROS formation in ambient air.