Alcohol consumption induces global gene expression changes in VTA dopaminergic neurons

Alcoholism is associated with dysregulation in the neural circuitry that mediates motivated and goal-directed behaviors. The dopaminergic (DA) connection between the ventral tegmental area (VTA) and the nucleus accumbens is viewed as a critical component of the neurocircuitry mediating alcohol's rewarding and behavioral effects. We sought to determine the effects of binge alcohol drinking on global gene expression in VTA DA neurons. Alcohol-preferring C57BL/6J × FVB/NJ F1 hybrid female mice were exposed to a modified drinking in the dark (DID) procedure for 3 weeks, while control animals had access to water only. Global gene expression of laser-captured tyrosine hydroxylase (TH)-positive VTA DA neurons was measured using microarrays. A total of 644 transcripts were differentially expressed between the drinking and nondrinking mice, and 930 transcripts correlated with alcohol intake during the last 2 days of drinking in the alcohol group. Bioinformatics analysis of alcohol-responsive genes identified molecular pathways and networks perturbed in DA neurons by alcohol consumption, which included neuroimmune and epigenetic functions, alcohol metabolism and brain disorders. The majority of genes with high and specific expression in DA neurons were downregulated by or negatively correlated with alcohol consumption, suggesting a decreased activity of DA neurons in high drinking animals. These changes in the DA transcriptome provide a foundation for alcohol-induced neuroadaptations that may play a crucial role in the transition to addiction.

Role of the IL-1 receptor antagonist in ethanol-induced regulation of GABAergic transmission in the central amygdala

The IL-1 receptor antagonist (IL-1ra), encoded by the Il1rn gene, is an endogenous antagonist of the IL-1 receptor. Studies of Il1rn knockout (KO) and wild type (WT) mice identified differences in several ethanol-related behaviors, some of which may be mediated by GABAergic transmission in the central nucleus of the amygdala (CeA). In this study we examined phasic (both evoked and spontaneous) and tonic GABAergic transmission in the CeA of Il1rn KO and WT mice and the ethanol sensitivity of these GABAergic synapses. The mean amplitude of baseline evoked GABAA-inhibitory postsynaptic potentials (IPSPs), and the baseline frequency of spontaneous GABAA-inhibitory postsynaptic currents (sIPSCs), but not the frequency of miniature GABAA-IPSCs (mIPSCs), were significantly increased in KO compared to WT mice, indicating enhanced presynaptic action potential-dependent GABA release in the CeA of KO mice. In KO mice, we also found a cell-type specific switch in the ongoing tonic GABAA receptor conductance such that the tonic conductance in low threshold bursting (LTB) neurons is lost and a tonic conductance in late spiking (LS) neurons appears. Notably, the ethanol-induced facilitation of evoked and spontaneous GABA release was lost in most of the CeA neurons from KO compared to WT mice. Ethanol superfusion increased the sIPSC rise and decay times in both KO and WT mice, suggesting ethanol-induced postsynaptic effects. The pretreatment of CeA slices with exogenous IL-1ra (Kineret; 100ng/ml) returned sIPSC frequency in KO mice to the levels found in WT. Importantly, Kineret also restored ethanol-induced potentiation of the sIPSC frequency in the KO mice. These results show that IL-1ra regulates baseline GABAergic transmission in the CeA and is critical for the ethanol effects at these synapses.

Fibroblast growth factor 21 analogue LY2405319 lowers blood glucose in streptozotocin-induced insulin-deficient diabetic mice by restoring brown adipose tissue function

AIM

To investigate the effects of LY2405319, an analogue of fibroblast growth factor 21 (FGF21), on glucose homeostasis in streptozotocin (STZ)-induced insulin-deficient mice (STZ mice).

METHODS

Nine-week-old male C57BL/6J mice were administered a single intraperitoneal injection of STZ (150 mg/kg). One week later, after confirmation of hyperglycaemia, saline or LY2405319 (5 mg/kg) was injected subcutaneously daily for 4 weeks. Changes in glucose homeostasis, energy metabolism and brown adipose tissue (BAT) function were assessed.

RESULTS

The STZ mice had elevated blood glucose and reduced plasma FGF21 levels, impaired glucose uptake in the BAT, and BAT mitochondria with absent or swollen cristae and fewer lipid vacuoles. LY2405319 significantly reduced blood glucose levels and this was associated with increased BAT glucose uptake and changes in gene expression and morphology, indicating improved mitochondrial lipid metabolism in the BAT. Importantly, the ability of LY2405319 to lower blood glucose in STZ mice was compromised after removing interscapular BAT.

CONCLUSIONS

Our results show that LY2405319 reduces blood glucose levels in insulin-deficient diabetes by improving BAT metabolism. Additional studies investigating the therapeutic potential of FGF21 for the treatment of type 1 diabetes are warranted.

An optimized protocol for human M2 macrophages using M-CSF and IL-4/IL-10/TGF-β yields a dominant immunosuppressive phenotype

Monocytes are highly abundant circulatory effector cells and play a vital role in driving or resolving inflammatory processes depending on their activation phenotype. We investigated and compared a panel of polarization protocols of blood-derived monocytes to achieve a stable, optimal and effective regimen for in vitro induction of immunosuppressive human macrophages, evaluating their surface receptor expression, cytokine profile, scavenging function and ability to suppress T-cell proliferation. Importantly, we assessed the effect of copolarization or secondary pro-inflammatory stimulation of a primary anti-inflammatory activation phenotype. A combination of IL-4/IL-10/TGF-β yielded a relatively stable and dominant immunosuppressive phenotype characterized by higher IL-10 production and down-regulated TNF-α, IL-6, CD86, CD274 and MHC II expression. Functionally, IL-4/IL-10/TGF-β-stimulated macrophages (M2) had a potent deactivating effect on a subsequent pro-inflammatory LPS/IFNγ-activated macrophage (M1) stimulation and significantly suppressed T-cell proliferation. Monocytes derived from patients with chronic inflammatory diseases could be induced to be anti-inflammatory using this protocol. Pre-differentiation with GM-CSF or M-CSF was further demonstrated to enhance final M1/M2 activation status. Our findings indicate a robust polarization protocol for generation of specific immunosuppressive human monocyte-derived macrophages.

Effects of resistance training on central blood pressure in obese young men

Central blood pressure is a predictor of the risk of cardiovascular disease (CVD), and the effects of resistance training (RT) on central blood pressure are largely unknown. This study explored the effects of high-intensity RT on central blood pressure, indices of arterial stiffness and wave reflection and inflammatory/atherogenic markers in overweight or obese, sedentary young men. Thirty-six participants were randomized to RT (12 weeks of training, 3/wk, n=28) or control groups (C, 12 weeks of no training, n=8) and assessed for changes in central and brachial blood pressures, augmentation index (AIx), carotid-femoral pulse wave velocity (cfPWV), carotid intima-media thickness (cIMT), body composition, lipids and inflammatory/atherogenic markers. High-intensity RT resulted in decreased central and brachial systolic/diastolic blood pressures (all P0.03), despite not altering AIx (P=0.34) or cfPWV (P=0.43). The vascular endothelial growth factor increased (P=0.03) after RT, without any change in cIMT, C-reactive protein, oxidized LDL (oxLDL) or other inflammatory markers (all P0.1). Changes in the central systolic blood pressure (cSBP) were positively correlated with changes in oxLDL (r=0.42, P=0.03) and soluble E-selectin (r=0.41, P=0.04). In overweight/obese young men, high-intensity RT decreases cSBP, independently of weight loss and changes in arterial stiffness. The cardioprotective effects of RT may be related to effects on central blood pressure.

Trajectories of loneliness during childhood and adolescence: predictors and health outcomes

The present study employed latent growth mixture modeling to discern distinct trajectories of loneliness using data collected at 2-year intervals from age 7-17 years (N = 586) and examine whether measures taken at age 5 years were good predictors of group membership. Four loneliness trajectory classes were identified: (1) low stable (37% of the sample), (2) moderate decliners (23%), (3) moderate increasers (18%), and (4) relatively high stable (22%). Predictors at age 5 years for the high stable trajectory were low trust beliefs, low trusting, low peer acceptance, parent reported negative reactivity, an internalizing attribution style, low self-worth, and passivity during observed play. The model also included outcome variables. We found that both the high stable and moderate increasing trajectories were associated with depressive symptoms, a higher frequency of visits to the doctor, and lower perceived general health at age 17. We discuss implications of findings for future empirical work.

Linking GABA(A) receptor subunits to alcohol-induced conditioned taste aversion and recovery from acute alcohol intoxication

GABA type A receptors (GABA(A)-R) are important for ethanol actions and it is of interest to link individual subunits with specific ethanol behaviors. We studied null mutant mice for six different GABA(A)-R subunits (α1, α2, α3, α4, α5 and δ). Only mice lacking the α2 subunit showed reduction of conditioned taste aversion (CTA) to ethanol. These results are in agreement with data from knock-in mice with mutation of the ethanol-sensitive site in the α2-subunit (Blednov et al., 2011). All together, they indicate that aversive property of ethanol is dependent on ethanol action on α2-containing GABA(A)-R. Deletion of the α2-subunit led to faster recovery whereas absence of the α3-subunit slowed recovery from ethanol-induced incoordination (rotarod). Deletion of the other four subunits did not affect this behavior. Similar changes in this behavior for the α2 and α3 null mutants were found for flurazepam motor incoordination. However, no differences in recovery were found in motor-incoordinating effects of an α1-selective modulator (zolpidem) or an α4-selective agonist (gaboxadol). Therefore, recovery of rotarod incoordination is under control of two GABA(A)-R subunits: α2 and α3. For motor activity, α3 null mice demonstrated higher activation by ethanol (1 g/kg) whereas both α2 (-/-) and α3 (-/Y) knockout mice were less sensitive to ethanol-induced reduction of motor activity (1.5 g/kg). These studies demonstrate that the effects of ethanol at GABAergic synapses containing α2 subunit are important for specific behavioral effects of ethanol which may be relevant to the genetic linkage of the α2 subunit with human alcoholism.

Behavioral actions of alcohol: phenotypic relations from multivariate analysis of mutant mouse data

Behavioral studies on genetically diverse mice have proven powerful for determining relationships between phenotypes and have been widely used in alcohol research. Most of these studies rely on naturally occurring genetic polymorphisms among inbred strains and selected lines. Another approach is to introduce variation by engineering single-gene mutations in mice. We have tested 37 different mutant mice and their wild-type controls for a variety (31) of behaviors and have mined this data set by K-means clustering and analysis of correlations. We found a correlation between a stress-related response (activity in a novel environment) and alcohol consumption and preference for saccharin. We confirmed several relationships detected in earlier genetic studies, including positive correlation of alcohol consumption with saccharin consumption and negative correlations with conditioned taste aversion and alcohol withdrawal severity. Introduction of single-gene mutations either eliminated or greatly diminished these correlations. The three tests of alcohol consumption used (continuous two-bottle choice and two limited access tests: drinking in the dark and sustained high alcohol consumption) share a relationship with saccharin consumption, but differ from each other in their correlation networks. We suggest that alcohol consumption is controlled by multiple physiological systems where single-gene mutations can disrupt the networks of such systems.

Identifying changes in the synaptic proteome of cirrhotic alcoholic superior frontal gyrus

Hepatic complications are a common side-effect of alcoholism. Without the detoxification capabilities of the liver, alcohol misuse induces changes in gene and protein expression throughout the body. A global proteomics approach was used to identify these protein changes in the brain. We utilised human autopsy tissue from the superior frontal gyrus (SFG) of six cirrhotic alcoholics, six alcoholics without comorbid disease, and six non-alcoholic non-cirrhotic controls. Synaptic proteins were isolated and used in two-dimensional differential in-gel electrophoresis coupled with mass spectrometry. Many expression differences were confined to one or other alcoholic sub-group. Cirrhotic alcoholics showed 99 differences in protein expression levels from controls, of which half also differed from non-comorbid alcoholics. This may reflect differences in disease severity between the sub-groups of alcoholics, or differences in patterns of harmful drinking. Alternatively, the protein profiles may result from differences between cirrhotic and non-comorbid alcoholics in subjects’ responses to alcohol misuse. Ten proteins were identified in at least two spots on the 2D gel; they were involved in basal energy metabolism, synaptic vesicle recycling, and chaperoning. These post-translationally modified isoforms were differentially regulated in cirrhotic alcoholics, indicating a level of epigenetic control not previously observed in this disorder.

Testing the silence of mutations: Transcriptomic and behavioral studies of GABA(A) receptor α1 and α2 subunit knock-in mice

Knock-in mice were constructed with mutations in the α1 (H(270), A(277)) and α2 (H(270), A(277)) subunits of the GABAA receptor, which resulted in receptors that lacked modulation by ethanol but retained normal responses to GABA in vitro. A key question is whether these mutant receptors also function normally in vivo. Perturbation of brain function was evaluated by gene expression profiling in the cerebral cortex and by behavioral pharmacology experiments with GABAergic drugs. Analysis of individual transcripts found only six transcripts that were changed in α1 knock-in mice and three in the α2 mutants (p<0.05, corrected for multiple comparisons). Two transcripts that are sensitive to neuronal activity, Arc and Fos, increased about 250% in the α2 mutants, and about 50% in the α1 mutants. Behavioral effects (loss of righting reflex, rotarod) of flurazepam and pentobarbital were not different between α2 mutants and wild-type, but they were enhanced for α1 knock-in mice. These results indicate that introduction of these mutations in the α2 subunit of the GABAA receptor does not produce marked perturbation of brain function, as measured by gene expression and GABAergic behavioral responses, but the same mutations in the α1 subunit produce more pronounced changes, especially in GABAergic function.

Loss of ethanol conditioned taste aversion and motor stimulation in knockin mice with ethanol-insensitive α2-containing GABA(A) receptors

GABA type A receptors (GABA(A)-Rs) are potential targets of ethanol. However, there are multiple subtypes of this receptor, and, thus far, individual subunits have not been definitively linked with specific ethanol behavioral actions. Interestingly, though, a chromosomal cluster of four GABA(A)-R subunit genes, including α2 (Gabra2), was associated with human alcoholism (Am J Hum Genet 74:705-714, 2004; Pharmacol Biochem Behav 90:95-104, 2008; J Psychiatr Res 42:184-191, 2008). The goal of our study was to determine the role of receptors containing this subunit in alcohol action. We designed an α2 subunit with serine 270 to histidine and leucine 277 to alanine mutations that was insensitive to potentiation by ethanol yet retained normal GABA sensitivity in a recombinant expression system. Knockin mice containing this mutant subunit were tested in a range of ethanol behavioral tests. These mutant mice did not develop the typical conditioned taste aversion in response to ethanol and showed complete loss of the motor stimulant effects of ethanol. Conversely, they also demonstrated changes in ethanol intake and preference in multiple tests. The knockin mice showed increased ethanol-induced hypnosis but no difference in anxiolytic effects or recovery from acute ethanol-induced motor incoordination. Overall, these studies demonstrate that the effects of ethanol at GABAergic synapses containing the α2 subunit are important for specific behavioral effects of ethanol that may be relevant to the genetic linkage of this subunit with human alcoholism.

Inhaled anesthetic responses of recombinant receptors and knockin mice harboring α2(S270H/L277A) GABA(A) receptor subunits that are resistant to isoflurane

The mechanism by which the inhaled anesthetic isoflurane produces amnesia and immobility is not understood. Isoflurane modulates GABA(A) receptors (GABA(A)-Rs) in a manner that makes them plausible targets. We asked whether GABA(A)-R α2 subunits contribute to a site of anesthetic action in vivo. Previous studies demonstrated that Ser270 in the second transmembrane domain is involved in the modulation of GABA(A)-Rs by volatile anesthetics and alcohol, either as a binding site or a critical allosteric residue. We engineered GABA(A)-Rs with two mutations in the α2 subunit, changing Ser270 to His and Leu277 to Ala. Recombinant receptors with these mutations demonstrated normal affinity for GABA, but substantially reduced responses to isoflurane. We then produced mutant (knockin) mice in which this mutated subunit replaced the wild-type α2 subunit. The adult mutant mice were overtly normal, although there was evidence of enhanced neonatal mortality and fear conditioning. Electrophysiological recordings from dentate granule neurons in brain slices confirmed the decreased actions of isoflurane on mutant receptors contributing to inhibitory synaptic currents. The loss of righting reflex EC(50) for isoflurane did not differ between genotypes, but time to regain the righting reflex was increased in N(2) generation knockins. This effect was not observed at the N(4) generation. Isoflurane produced immobility (as measured by tail clamp) and amnesia (as measured by fear conditioning) in both wild-type and mutant mice, and potencies (EC(50)) did not differ between the strains for these actions of isoflurane. Thus, immobility or amnesia does not require isoflurane potentiation of the α2 subunit.

Altered natural killer (NK) cell frequency and phenotype in latent autoimmune diabetes in adults (LADA) prior to insulin deficiency

Approximately 10% of the patients diagnosed with type 2 diabetes (T2D) have detectable serum levels of glutamic acid decarboxylase 65 autoantibodies (GADA). These patients usually progress to insulin dependency within a few years, and are classified as being latent autoimmune diabetes in adults (LADA). A decrease in the frequency of peripheral blood natural killer (NK) cells has been reported recently in recent-onset T1D and in high-risk individuals prior to the clinical onset. As NK cells in LADA patients have been investigated scarcely, the aim of this study was to use multicolour flow cytometry to define possible deficiencies or abnormalities in the frequency or activation state of NK cells in LADA patients prior to insulin dependency. All patients were GADA-positive and metabolically compensated, but none were insulin-dependent at the time blood samples were taken. LADA patients exhibited a significant decrease in NK cell frequency in peripheral blood compared to healthy individuals (P=0.0018), as reported previously for recent-onset T1D patients. Interestingly, NKG2D expression was increased significantly (P<0.0001), whereas killer cell immunoglobulin-like receptor (KIR)3DL1 expression was decreased (P<0.0001) within the NK cell population. These observations highlight a defect in both frequency and activation status of NK cells in LADA patients and suggest that this immunological alteration may contribute to the development of autoimmune diabetes by affecting peripheral tolerance. Indeed, recent evidence has demonstrated a regulatory function for NK cells in autoimmunity. Moreover, the decrease in NK cell number concords with observations obtained in recent-onset T1D, implying that similar immunological dysfunctions may contribute to the progression of both LADA and T1D.

Behavioral differences between C57BL/6J x FVB/NJ and C57BL/6J x NZB/B1NJ F1 hybrid mice: relation to control of ethanol intake

C57BL/6J x FVB/NJ F1 (B6 x FVB) mice consume more alcohol than C57BL/6J x NZB/B1NJ F1 (B6 x NZB) mice and this high alcohol consumption is stable after abstinence whereas B6 x NZB show reduced consumption, thus providing models of Sustained Alcohol Preference (SAP) and Reduced Alcohol Preference (RAP). In female hybrids, we assessed several behavioral responses to define behaviors which might predict SAP and RAP. B6 x FVB exhibited less severe ethanol-induced conditioned taste aversion and were less sensitive to ethanol-induced loss of righting reflex than B6 x NZB. Both hybrids demonstrated ethanol-induced place preference and a low ethanol withdrawal severity. We found that these hybrids differ in their sensitivity to the aversive and sedative, but not rewarding, effects of ethanol. Results of elevated plus maze, mirror chamber, and locomotor tests reveal B6 x FVB mice are less anxious and more active than B6 x NZB mice. Results obtained offer insights about factors that determine SAP and RAP in these new genetic models of alcohol consumption.

In vitro biocompatibility of hydroxyapatite-reinforced polymeric composites manufactured by selective laser sintering

The selective laser sintering (SLS) technique was used to manufacture hydroxyapatite-reinforced polyethylene and polyamide composites as potential customized maxillofacial implants. In vitro tests were carried out to assess cellular responses, in terms of cell attachment, morphology, proliferation, differentiation, and mineralized nodule formation, using primary human osteoblast cells. This study showed that the SLS composite processed was biocompatible, with no adverse effects observed on cell viability and metabolic activity, supporting a normal metabolism and growth pattern for osteoblasts. Positive von Kossa staining demonstrated the presence of bone-like mineral on the SLS materials. Higher hydroxyapatite content composites enhanced cell proliferation, increased alkaline phosphatase activity, and produced more osteocalcin. The present findings showed that SLS materials have good in vitro biocompatibility and hence demonstrated biologically the potential of SLS for medical applications.

Bidirectional modulation of isoflurane potency by intrathecal tetrodotoxin and veratridine in rats

BACKGROUND AND PURPOSE

Results from several studies point to voltage-gated Na(+) channels as potential mediators of the immobility produced by inhaled anaesthetics. We hypothesized that the intrathecal administration of tetrodotoxin, a drug that blocks Na(+) channels, should enhance anaesthetic potency, and that concurrent administration of veratridine, a drug that augments Na(+) channel opening, should reverse the increase in potency.

EXPERIMENTAL APPROACH

We measured the change in isoflurane potency for reducing movement in response to a painful stimulus as defined by MAC (minimum alveolar concentration of anaesthetic required to abolish movement in 50% of subjects) caused by intrathecal infusion of various concentrations of tetrodotoxin into the lumbothoracic subarachnoid space of rats, and the change in MAC caused by the administration of a fixed dose of tetrodotoxin plus various doses of intrathecal veratridine.

KEY RESULTS

Intrathecal infusion of tetrodotoxin (0.078-0.63 microM) produced a reversible dose-related decrease in MAC, of more than 50% at the highest concentration. Intrathecal co-administration of veratridine (1.6-6.4 microM) reversed this decrease in a dose-related manner, with nearly complete reversal at the highest veratridine dose tested.

CONCLUSIONS AND IMPLICATIONS

Intrathecal administration of tetrodotoxin increases isoflurane potency (decreases isoflurane MAC), and intrathecal administration of veratridine counteracts this effect in vivo. These findings are consistent with a role for voltage-gated Na(+) channel blockade in the immobility produced by inhaled anaesthetics.

Characterization, quantification, and replication of human sinus bone for surgery simulation phantoms

The requirement for artificial but realistic, tactile, anatomical models for surgical practice in medical simulation is increasingly evident and shows potential for greater efficiency and availability, and lower costs. Anatomically correct, detailed models with the physical surgical characteristics of real tissue, combined with the ability to reproduce one-off cases, would provide an invaluable tool in the development of surgery. This research work investigates the capture of geometrical and physical data from the human sinus to subsequently direct the production and optimization of such simulation phantoms. Micro-computed tomography analysis of the entire sinus was performed to characterize the sinus complex geometry. Following an extensive review, specialized mechanical testing apparatus and methods relevant to the surgical methods employed were designed and produced. This provided comparative analysis methods for both biological and artificial phantom materials and allowed the optimization of phantom materials with respect to the derived target values.

Popliteal vein compression syndrome: obesity, venous disease and the popliteal connection

Objectives

Obesity and venous disease are commonly encountered together. The aetio- logical relationship, however, has not been clear. Popliteal venous compression (PVC) has been encountered both on ultrasound and venographically. In this study, patients with symptoms and/or signs of chronic venous hypertension with PVC were investigated and the relationship to obesity was defined.

Methods

A total of 89 patients were included in the study, of which 49 limbs were classified as having PVC defined as a greater than 90% reduction in the maximum internal diameter (ID) of the popliteal vein (POPV) with knee locking. Forty consecutive limbs with venous disease with no evidence of PVC were used as controls. The body mass index (BMI) of each group was calculated and the clinical symptoms and signs were documented. After the failure of conservative treatment, 30 of the 49 underwent open popliteal decompression.

Results

Patients with PVC were found to have a BMI of 34.6 ± 6.2 compared with 25.3 ± 3.0 of the controls. The POPV ID in the PVC group before and after knee locking changed from 11.7 ± 5.0 to 1.0 ± 2.1 mm, respectively. Postoperatively, the POPV ID before and after knee locking changed from 10.2 ± 2.2 to 9.0 ± 1.5 mm, respectively. At 16.2 ± 12.1 months follow-up, all the major clinical parameters improved at a statistically significant level.

Conclusions

There appears to be a relationship between obesity, chronic venous disease and PVC. POPV compression syndrome may clarify the previously unexplained venous presentations. Surgical decompression provides good results in patients unresponsive to conservative treatment.

Deletion of vanilloid receptor (TRPV1) in mice alters behavioral effects of ethanol

The vanilloid receptor TRPV1 is activated by ethanol and this may be important for some of the central and peripheral actions of ethanol. To determine if this receptor has a role in ethanol-mediated behaviors, we studied null mutant mice in which the Trpv1 gene was deleted. Mice lacking this gene showed significantly higher preference for ethanol and consumed more ethanol in a two-bottle choice test as compared with wild type littermates. Null mutant mice showed shorter duration of loss of righting reflex induced by low doses of ethanol (3.2 and 3.4 g/kg) and faster recovery from motor incoordination induced by ethanol (2 g/kg). However, there were no differences between null mutant and wild type mice in severity of ethanol-induced acute withdrawal (4 g/kg) or conditioned taste aversion to ethanol (2.5 g/kg). Two behavioral phenotypes (decreased sensitivity to ethanol-induced sedation and faster recovery from ethanol-induced motor incoordination) seen in null mutant mice were reproduced in wild type mice by injection of a TRPV1 antagonist, capsazepine (10 mg/kg). These two ethanol behaviors were changed in the opposite direction after injection of capsaicin, a selective TRPV1 agonist, in wild type mice. The studies provide the first evidence that TRPV1 is important for specific behavioral actions of ethanol.

Advanced computer-aided design for bone tissue-engineering scaffolds

The design of scaffolds with an intricate and controlled internal structure represents a challenge for tissue engineering. Several scaffold-manufacturing techniques allow the creation of complex architectures but with little or no control over the main features of the channel network such as the size, shape, and interconnectivity of each individual channel, resulting in intricate but random structures. The combined use of computer-aided design (CAD) systems and layer-manufacturing techniques allows a high degree of control over these parameters with few limitations in terms of achievable complexity. However, the design of complex and intricate networks of channels required in CAD is extremely time-consuming since manually modelling hundreds of different geometrical elements, all with different parameters, may require several days to design individual scaffold structures. An automated design methodology is proposed by this research to overcome these limitations. This approach involves the investigation of novel software algorithms, which are able to interact with a conventional CAD program and permit the automated design of several geometrical elements, each with a different size and shape. In this work, the variability of the parameters required to define each geometry has been set as random, but any other distribution could have been adopted. This methodology has been used to design five cubic scaffolds with interconnected pore channels that range from 200 to 800 μm in diameter, each with an increased complexity of the internal geometrical arrangement. A clinical case study, consisting of an integration of one of these geometries with a craniofacial implant, is then presented.

Polymorphic microsatellite loci for the common marmoset (Callithrix jacchus) designed using a cost- and time-efficient method

We describe a cost- and time-efficient method for designing new microsatellite markers in any species with substantial genomic DNA sequence data available. Using this technique, we report 14 new polymorphic dinucleotide microsatellite loci isolated from the common marmoset. The relative yield of new polymorphisms was higher with less labor than described in previous marmoset studies. Of 20 loci initially evaluated, 14 were polymorphic and amplified reliably (70% success rate). The number of alleles ranged from 3 to 9 with heterozygosity varying from 0.48 to 0.83.