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Publication
Journal: Advances in Therapy
June/21/2007
Abstract
Schizophrenia is a devastating psychiatric disorder. Clozapine has long been the gold standard for treatment of patients with treatment-resistant schizophrenia; however, some patients are only partially responsive to clozapine treatment. Augmentation of clozapine treatment might enhance its effectiveness in partial responders, but only a few studies have investigated possible augmentation strategies. This study compared the effectiveness and tolerability of the combination of amisulpride and clozapine with the combination of quetiapine and clozapine in patients who were only partially responsive to clozapine monotherapy. Fifty-six treatment-resistant patients who were partially responsive to clozapine were randomly assigned to receive amisulpride or quetiapine along with an ongoing stable dose of clozapine. Fifty patients completed the study. Patients were evaluated at baseline and at the first, third, sixth, and eighth weeks. Efficacy measures consisted of the Brief Psychiatric Rating Scale (BPRS), the Scale for the Assessment of Negative Symptoms (SANS), the Scale for the Assessment of Positive Symptoms (SAPS), and the Clinical Global Impression (CGI) scale. Tolerability and adverse effects were assessed with the Udvalg for Kliniske Undersogelser (UKU) Side Effect Rating Scale and the Simpson Angus Scale (SAS). A substantial improvement occurred in both groups by the end of the eighth week; however, the improvement associated with amisulpride was significantly greater than that seen with quetiapine. This difference was noted as early as the third week of follow-up in terms of CGI scores, and by the sixth week with regard to BPRS, SANS, and SAPS scores. Both drugs were well tolerated, as measured by UKU and SAS. Improvement favoring clozapine+amisulpride could be attributed to the selective D2/D3 binding property of amisulpride, which had an additional effect in improving symptoms of schizophrenia. The authors concluded that amisulpride seems to be effective and well tolerated for augmentation purposes in clozapine-resistant patients.
Publication
Journal: Journal of Cerebral Blood Flow and Metabolism
October/3/2007
Abstract
This is the first in vivo determination of the vesicular monoamine transporter (VMAT2) density (B(max)) and ligand-transporter affinity (K(d)(app)) in six unilaterally 6-hydroxydopamine (6-OHDA) lesioned rats using micro-positron emission tomography (PET) imaging with [(11)C]-(+)-alpha-dihydrotetrabenazine (DTBZ). A multiple ligand concentration transporter assay (MLCTA) was used to determine a B(max) value of 178+/-32 pmol/mL and a K(d)(app) of 47.7+/-9.3 pmol/mL for the non-lesioned side and 30.52+/-5.84 and 43.4+/-15.52 pmol/mL for the lesioned side, respectively. While B(max) was significantly different between the two sides, no significant difference was observed for the K(d)(app). In addition to demonstrating the feasibility of in vivo Scatchard analysis in rats, these data confirm the expectation that a 6-OHDA lesion does not affect the affinity; a much simpler binding potential (BP) measure can thus be used as a marker of lesion severity (LS) in this rat model of Parkinson's disease. A transporter occupancy curve demonstrated negligible transporter occupancy ( approximately 1%) at a specific activity (SA) of 1100 nCi/pmol (assuming an injected dose of 100 microCi/100 g), while 10% occupancy was estimated at 100 nCi/pmol. An indirect measurement indicated that the degree of occupancy as a function of SA is independent of LS. Finally, BP measurement reproducibility was assessed and found to be 11%+/-7% for the healthy and 8%+/-12% for the lesioned side. Quantitative PET results can thus be obtained even for severely lesioned animals with the striatum on one side not clearly visible provided accurate image analysis methods are used.
Publication
Journal: Proteomics
December/7/2010
Abstract
Irritable bowel syndrome (IBS) is one of the most common functional disorders of the gastrointestinal tract. It is characterized by abdominal pain and changes in bowel habits. Various studies have investigated the pathophysiologic processes underlying IBS, but the mechanism remains poorly understood. In the present study, we established an IBS model and identified differentially expressed proteins in colon tissue of IBS rats compared with healthy controls by 2-D gel electrophoresis, MALDI-TOF-MS, and Western blot analysis. Our results showed that 13 of the 1396 protein spots on 2-D gel were differently expressed between the IBS and control groups. Ontological analysis of these proteins revealed primary roles in catalytic activity (protein disulfide-isomerase A3, glyoxalase I, cathepsin S, alpha-enolase), structural support (cytokeratin 8), antioxidant activity (peroxiredoxin-6), protein binding (transgelin, serpin peptidase inhibitor B5), and signal transduction (40S ribosomal protein SA). Protein disulfide-isomerase A3 and cytokeratin 8 overexpression in IBS were confirmed by Western blot. The findings indicate that multiple proteins are involved in IBS processes that influence intestinal tract immunity, inflammation, and nerve regulation. Our study provides useful candidate genes and proteins for further investigation.
Publication
Journal: Asia Pacific Journal of Clinical Nutrition
April/30/2006
Abstract
Tocotrienols and tocopherols represent the two subgroups that make up the vitamin E family of compounds. However, tocotrienols display significantly more potent apoptotic activity in neoplastic mammary epithelial cells than tocopherols. Studies were conducted to determine the intracellular mechanism(s) mediating tocotrienol-induced apoptosis in neoplastic +SA mouse mammary epithelial cells in vitro. An initial step in apoptosis is the activation of 'initiator' caspases (caspase-8 or -9) that subsequently activate 'effector' caspases (caspase-3, -6 and -7) and induce apoptosis. Treatment with cytotoxic doses of alpha-tocotrienol (20 microM) resulted in a time-dependent increase in caspase-8 and caspase-3 activity. Combined treatment with specific caspase-8 or caspase-3 inhibitors completely blocked alpha-tocotrienol-induced apoptosis and caspase-8 or caspase-3 activity, respectively. In contrast, alpha-tocotrienol treatment had no effect on caspase-9 activation, and combined treatment with a specific caspase-9 inhibitor did not block alpha-tocotrienol-induced apoptosis in (+)SA cells. Since caspase-8 activation is associated with the activation of death receptors, such as Fas, tumor necrosis factor (TNF), or TNF-related apoptosis-inducing ligand (TRAIL) receptors, studies were conducted to determine the exact death receptor(s) and ligand(s) involved in mediating tocotrienol-induced caspase-8 activation and apoptosis. Treatment with Fas-ligand (FasL), Fas-activating antibody, or TRAIL failed to induce cell death in (+)SA neoplastic mammary epithelial cells, suggesting that these cells are resistant to death receptor-induced apoptosis. Moreover, treatment with cytotoxic doses of alpha-tocotrienol did not alter the intracellular levels of Fas, FasL, or Fas-associated death domain (FADD) in these cells. Western blot analysis also showed that alpha-tocotrienol did not induce FasL or FADD translocation from the cytosolic to membrane fraction in these cells. Finally, treatment with Fas-blocking antibody did not reverse the tocotrienol-induced apoptosis in (+)SA cells. These data demonstrate that tocotrienol-induced caspase-8 activation and apoptosis is not mediated through death receptor activation in malignant (+)SA mammary epithelial cells. Resistance to death receptor-induced apoptosis has been shown to be associated with increased expression of apoptosis-inhibitory proteins, such as FLICE-inhibitory protein (FLIP), and enhanced signalling of the phosphatidylinositol 3-kinase (PI3K)/PI3K-dependent kinase (PDK)/Akt mitogenic pathway. Additional studies showed that treatment with cytotoxic doses of alpha-tocotrienol decreased total, membrane, and cytosolic levels of FLIP, and reduced phosphorylated PDK-1 (active) and phosphorylated-Akt (active) levels in these cells. In summary, these findings demonstrate that tocotrienol-induced caspase-8 activation and apoptosis in malignant (+)SA mammary epithelial cells is not mediated through the activation of death receptors, but appears to result from the suppression of the PI3K/PDK/Akt mitogenic signalling pathway, and subsequent reduction in intracellular FLIP expression.
Publication
Journal: Oncogene
April/20/1994
Abstract
Amplification of 12q13-14 occurs in a subset of human sarcomas including malignant fibrous histiocytoma and liposarcoma. This chromosomal region has previously been found to include a number of growth-related genes including the GLI proto-oncogene and the p53-associated protein, MDM2. We now report the characterization of SAS (sarcoma amplified sequence), a novel transcript found in this region. Sequence analysis demonstrates that SAS is a novel member of a transmembrane protein family (transmembrane 4 superfamily or TM4SF) thought to be involved in growth-related cellular processes. This observation adds a TM4SF protein to the cluster of genes at 12q13-14 frequently amplified in human sarcomas.
Publication
Journal: The Journal of trauma
December/21/2006
Abstract
BACKGROUND
Situation awareness (SA) is defined as the perception of elements in the environment within a volume of time and space, the comprehension of their meaning, and the projection of their status in the near future. This construct is vital to decision making in intense, dynamic environments. It has been used in aviation as it relates to pilot performance, but has not been applied to medical education. The most widely used objective tool for measuring trainee SA is the Situation Awareness Global Assessment Technique (SAGAT). The purpose of this study was to design and validate SAGAT for assessment of practical trauma skills, and to compare SAGAT results to traditional checklist style scoring.
METHODS
Using the Human Patient Simulator, we designed SAGAT for practical trauma skills assessment based on Advanced Trauma Life Support objectives. Sixteen subjects (four staff surgeons, four senior residents, four junior residents, and four medical students) participated in three scenarios each. They were assessed using SAGAT and traditional checklist assessment. A questionnaire was used to assess possible confounding factors in attaining SA and overall trainee satisfaction.
RESULTS
SAGAT was found to show significant difference (analysis of variance; p < 0.001) in scores based on level of training lending statistical support to construct validity. SAGAT was likewise found to display reliability (Cronbach's alpha 0.767), and significant scoring correlation with traditional checklist performance measures (Pearson's coefficient 0.806). The questionnaire revealed no confounding factors and universal satisfaction with the human patient simulator and SAGAT.
CONCLUSIONS
SAGAT is a valid, reliable assessment tool for trauma trainees in the dynamic clinical environment created by human patient simulation. Information provided by SAGAT could provide specific feedback, direct individualized teaching, and support curriculum change. Introduction of SAGAT could improve the current assessment model for practical trauma education.
Publication
Journal: Leukemia Research
January/28/2008
Abstract
Chronic exposure to benzene can result in transient hematotoxicity (benzene poisoning, BP) or persistent bone marrow pathology including dysplasia and/or acute myeloid leukemia. We recently described a persistent bone marrow dysplasia with unique dysplastic and inflammatory features developing in individuals previously exposed to benzene (BID) [Irons RD, Lv L, Gross SA, Ye X, Bao L, Wang XQ, et al. Chronic exposure to benzene results in a unique form of dysplasia. Leuk Res 2005;29:1371-80]. In this study we investigated the association of single nucleotide polymorphisms (SNP) (-863 (C->>A), -857 (C->>T), -308 (G->>A), -238 (G->>A)) in the promoter region of the cytokine, tumor necrosis factor-alpha (TNF-alpha) on the development of BP, persistent BID and de novo myelodysplastic syndrome (MDS) in 394 individuals. Only the -238 (G->>A) polymorphism was significantly associated with the development of BID (odds ratio (OR)=7.4; 95% C.I. 1.23-44.7) and was specific for BID and not de novo MDS or BP. These findings are consistent with a role for inflammation in the development of BID and suggest that cell-specific alterations in TNF-alpha expression may promote clonal selection in the evolution of neoplastic hematopoietic disease.
Publication
Journal: European Journal of Neuroscience
February/24/2008
Abstract
The mesolimbic dopaminergic system is widely recognized to be critical to the neurobiology of cocaine reward and addiction. The neuronal protein, alpha-synuclein, is an important regulator in dopaminergic transmission. It interacts with the dopamine transporter, and regulates dopaminergic content, neurotransmission and synaptic strength of dopaminergic neurons. Alpha-synuclein levels are elevated in midbrain dopamine neurons of chronic cocaine abusers, and its expression is increased in psychostimulant-treated animals [M.S. Brenz-Verca et al. (2003) J. Neurosci., 18, 1923-1938]. This suggests a role for alpha-synuclein in psychostimulant-induced behavioural effects. To investigate this hypothesis, we tested the effect of stimulation and silencing of alpha-synuclein expression in the nucleus accumbens (NAcc) on two cocaine-induced behavioural effects in the rat. For this purpose, animals were administered with lentiviruses driving alpha-synuclein overexpression under the control of a doxycycline regulatable promoter and/or with three lentiviruses expressing target-specific siRNAs, aimed at silencing alpha-synuclein mRNA expression. Animals were then tested for cocaine-induced locomotion (15 mg/kg i.p.) or cocaine-induced intravenous self-administration (SA; 0.7 mg/kg, 1 h/day). Overexpression of alpha-synuclein in the NAcc induced a 45% increase in locomotor activity and a 1.9-fold increase of cocaine SA, which could be abolished when the same animal was fed doxycycline. Furthermore, local inhibition of alpha-synuclein in the NAcc resulted in significant hypolocomotion activity and a decrease in SA. Our results demonstrate that alpha-synuclein is able to modulate cocaine-induced behavioural effects. This suggests that targeting alpha-synuclein function could provide new therapeutic strategies to treat cocaine abuse, for which there is no available treatment.
Publication
Journal: Atherosclerosis
April/7/2009
Abstract
OBJECTIVE
Elevated serum amyloid A (SAA) levels, like C-reactive protein (CRP), predict coronary events. Both induce monocyte tissue factor (TF), and peripheral blood mononuclear cells (PBMC) from patients with coronary artery disease (CAD) express higher TF in response to CRP. This study examined SAA induction of TF and tumour necrosis factor-alpha (TNF) in PBMC from patients with CAD and in monocytoid THP-1 cells.
RESULTS
PBMC from 26 males with CAD (15 stable angina, SA, and 11 acute coronary syndromes, ACS) and 14 male controls were stimulated with SAA. SAA promoted up to six-fold increase in TF activity (recalcification assay) on PBMC from patients, associated with elevated TF mRNA and protein. PBMC responded optimally when monocytes were adherent. Unlike CRP, SAA induced TF and TNF in THP-1 cells. SAA-induced TNF was dose-dependently inhibited by HDL. PBMC from patients with ACS expressed more basal TF (257.4+/-46.8 mU/10(6) PBMC vs. 131.0+/-12.5 mU/10(6) PBMC, P=0.003), and greater SAA-induced TF than cells from controls, whereas no difference was found between SA and controls (ACS 2246+/-493, SA 1364+/-206, controls 1091+/-113 mU/10(6) PBMC, with SAA 250 ng/mL, P=0.002 ACS vs. controls across the dose range). Importantly, SAA-induced TNF levels (ELISA) were much higher in patients with ACS than SA or controls (ACS 211+/-41, SA 108+/-16, controls 73+/-11 pg/mL, with SAA 250 ng/mL, P=0.001 ACS vs. controls or P=0.013 ACS vs. SA across the dose range). SAA-induced TF and TNF correlated positively with serum SAA levels in CAD, but not controls.
CONCLUSIONS
SAA is a prothrombotic and proinflammatory mediator in ACS which may contribute to atherogenesis and its complications.
Publication
Journal: Biochemical and Biophysical Research Communications
April/11/2010
Abstract
Recent characterization of the chromate reductase (CrS) from the thermophile Thermus scotoductus SA-01 revealed this enzyme to be related to the Old Yellow Enzyme (OYE) family. Here, we report the structure of a thermostable OYE homolog in its holoform at 2.2A as well as its complex with p-hydroxybenzaldehyde (pHBA). The enzyme crystallized as octamers with the monomers showing a classical TIM barrel fold which upon dimerization yields the biologically active form of the protein. A sulfate ion is bound above the si-side of the non-covalently bound FMN cofactor in the oxidized solved structure but is displaced upon pHBA binding. The active-site architecture is highly conserved as with other members of this enzyme family. The pHBA in the CrS complex is positioned by hydrogen bonding to the two conserved catalytic-site histidines. The most prominent structural difference between CrS and other OYE homologs is the size of the "capping domain". Thermostabilization of the enzyme is achieved in part through increased proline content within loops and turns as well as increased intersubunit interactions through hydrogen bonding and complex salt bridge networks. CrS is able to reduce the C=C bonds of alpha,beta-unsaturated carbonyl compounds with a preference towards cyclic substrates however no activity was observed towards beta-substituted substrates. Mutational studies have confirmed the role of Tyr177 as the proposed proton donor although reduction could still occur at a reduced rate when this residue was mutated to phenylalanine.
Publication
Journal: Genes, Brain and Behavior
September/24/2014
Abstract
Social and genetic factors can influence smoking behavior. Using olfactogustatory stimuli as the sensory cue for intravenous nicotine self-administration (SA), we previously showed that social learning of nicotine contingent odor cue prevented rats from developing conditioned taste aversion and allowed them to instead establish stable nicotine SA. We hypothesized that genetic factors influenced socially acquired nicotine SA. A heterogeneous stock (HS; N/NIH) of outbred rats was trained to self-administer nicotine using the social learning protocol. Both male and female HS rats acquired nicotine SA, but females self-administered more nicotine than males. After extinction, the context previously paired with nicotine SA, in conjunction with socially transmitted drug cues, was sufficient to cause reinstatement of drug-seeking behavior. Wide variation in both nicotine intake and reinstatement was observed. Using multiple regression analysis, we found that measures of social interaction were significant predictors of nicotine intake and reinstatement of drug seeking in both males and females. Furthermore, measures of depression were predictors of nicotine intake in both males and females, anxiety was a predictor only in males and response to novelty was a predictor only in females. In males, measures of both depression and anxiety predicted nicotine reinstatement. Together, these data supported the ideas that genetically determined propensities for emotional and social phenotypes are significant determinants for nicotine-reinforced behavior, and that the HS rat is a suitable tool for dissecting genetic mechanisms that may underlie the interaction between social behavior, anxiety, depression and smoking.
Publication
Journal: Archives of Virology
May/6/1993
Abstract
Homologs of the herpes simplex virus gB gene were identified in two alpha-herpesviruses of platyrrhine monkeys, Herpesvirus saimiri 1 (HVS 1) and H. ateles 1 (HVA 1). These genes were cloned and sequenced in their entirety. Analysis of the predicted amino acid sequences indicated that the gB glycoproteins of these two viruses are of similar size, have 10 Cys residues and 5 potential N-linked glycosylation sites which align exactly with those in other primate alpha-herpesvirus gB polypeptides, and have a similar distribution of predicted secondary structural features, all of which indicate a conserved structure of the gB polypeptide. Alignment of these two gB sequences with those of four other primate alpha-herpesviruses (SA 8, B virus, HSV 1 and HSV 2) revealed localized regions of extensive sequence divergence as well as highly conserved regions. On comparison of the six primate virus gB sequences, the gBs of the two platyrrhine monkey viruses form a subgroup separate from that of the four catarrhine virus gBs. The degree of relatedness of the HVA 1 and HVS 1 gB sequences to each other was equivalent to the degree of relatedness between the human and the cercopithecine monkey virus gB sequences.
Publication
Journal: Journal of Cellular Physiology
December/27/1994
Abstract
Calcium transients in single, human gingival fibroblasts were studied after mechanical stretching of flexible culture substrates. A model system was developed to reproducibly stretch and rapidly (<1 sec) refocus cells in the same focal plane so that changes in the concentration of free intracellular calcium ions ([Ca2+]i) were monitored without delay. Attached cells were grown on flexible bottom Petriperm dishes, loaded with fura-2/AM, and stretched by 1% or 2.8% of substrate area. The stretch caused no significant cell detachment or membrane lesions. A 1% stretch induce no calcium response, but a 2.8% stretch stimulated an initial calcium transient and the subsequent generation of [Ca2+]i oscillations of up to 2,000 sec. At 1% stretch, there was no calcium response. Cell shape and plating time were important determinants in the calcium response to mechanical stimulation: the responder cells were small and round without long processes. Major calcium transients were inhibited completely by 5 mM EGTA or by 10 microM gadolinium ions, by 50 microM nifedipine, or 250 microM verapamil, suggesting an influx of calcium through stretch-activated (SA) channels and L-type calcium channels. Depolarization by high KCl (144 mM) in the extracellular medium enhanced the amplitude of calcium transients by 54%. Calcium oscillations were not inhibited by preincubation with thapsigargin, caffeine, cholera toxin, staurosporine or 1-(5-isoquinolinesulfonyl)-2-methylpiperazine (H-7), indicating that IP3 sensitive pools, IP3 insensitive pools, GS alpha subunits, and protein kinase C, respectively, were not involved in the generation of calcium oscillations. Pretreatment with genistein, a specific tyrosine kinase inhibitor or cytochalasin D, an inhibitor of actin polymerization, or pertussis toxin, an inhibitor of Gi alpha and G(o) alpha subunits, completely abolished calcium transients and oscillations. These results indicate that Ca2+ flux due to mechanical stretching is likely mediated through SA ion channels and is dependent on tyrosine kinases, pertussis toxin-sensitive subunits of G-proteins, and actin filaments.
Publication
Journal: Clinical immunology and immunopathology
July/9/1996
Abstract
Alveolar macrophage-fibroblast interaction may be involved in the pathogenesis of interstitial lung diseases (ILD). Herein, we compared IL-6 secretion from alveolar macrophages (AM) and alveolar fibroblasts (AFb) recovered from patients with sarcoidosis (SA) and with diffuse interstitial fibrosis (DIF). Moreover, we evaluated the effect of IL-6 on the in vitro AFb proliferation in both diseases. AM and AFb from SA patients showed increased spontaneous secretion of IL-6 compared with cells from DIF subjects. Tumor necrosis factor-alpha (TNFalpha) and interleukin-1 (IL-1) enhanced IL-6 secretion and IL-6 mRNA transcription in AFb of SA patients. Addition of anti-IL-6 MoAbs increased AFb proliferation capacity in SA, but suppressed it in DIF. These results show that only SA AM and AFb secrete high levels of IL-6 which have suppressive effect on AFb proliferation. This may indicate a potential role of IL-6 in the fibrogenesis of ILD.
Publication
Journal: Molecular and Cellular Endocrinology
April/16/1997
Abstract
Human follicle-stimulating hormone (hFSH) and luteinizing hormone (hLH) are gonadotropins which are secreted as multiple forms by the pituitary. Evidence supporting the structural and functional heterogeneity of 15 purified hFSH isoforms and 20 purified hLH isoforms from pituitary extracts will be presented. Gonadotropin isoforms were purified by a combination of preparative isoelectric focusing and ion-exchange chromatography. The protein mass of each isoform was determined by amino acid analysis, which also correlated (data for hLH) (r = 0.999, P < 0.001, n = 15) with the UV area under the curve at 280 nm of the isoforms following gel-filtration HPLC. The alpha and beta subunits of FSH and LH were shown to be intact by SDS-PAGE under reducing condition, with no evidence of proteolytic nicking or presence of contaminating proteins. hFSH radioreceptor activity varied over a seven-fold range, and a positive correlation (r = 0.85, P < 0.001, n = 9) was observed between FSH receptor activity and the sialic acid (SA) content (1.5-13.7 mol SA/mol hFSH) of the isoforms, as determined by an HPLC-based microfluorometric assay. FSH in vitro activities varied over a similar range with a high correlation (r = 0.82, n = 15) with receptor activities, suggesting that the initial association of the hormone with the receptor is the key interaction with less differences attributed to subsequent effects in the signaling pathway. A similar result was seen with the hLH isoforms. To explore FSH/LH in vivo, the circulating half-life (LH/FSH) and the in vivo bioactivity (LH) using an acute in vivo assay was investigated. The clearance of hLH and hFSH showed a bi-exponential pattern for all isoform preparations with the proportion of the slower dissociating component (t 1/2 50-60 min) increasing three-fold with increasing sialic acid content of the isoform. The more rapidly cleared component (t 1/2 approx 10 min) is attributed to hepatically cleared gonadotropin, rather than gonadotropin equilibration between body compartments. The in vivo assay procedure for LH was based on the 24 h integrated plasma testosterone levels in rats following administration of graded doses of hLH isoform or standard. A 16-fold range in vivo activities between LH isoforms (n = 14) was observed. A comparison between hLH in vitro and in vivo activities showed a good correlation (r = 0.75) with the slope of the regression line (1.39) not significantly different from unity. These results suggest that in this acute in vivo assay method, the differences in circulating half-lives between hLH isoforms although large is not a key factor in their in vivo activity. However, in chronic in vivo assay systems the differences in clearance rates between isoforms may be important in their subsequent biological response. It is concluded that structural heterogeneity of FSH and LH contributes to functional differences, with a key interaction occurring at the receptor level. The contribution of sialic acid to these activities was also investigated.
Publication
Journal: Anaesthesia and Intensive Care
February/28/2002
Abstract
Moderate haemodilution enhances coagulability in vitro and in vivo as measured by thrombelastography (TEG). The mechanism has never been established. We have conducted an in vitro study to determine whether the effect can be moderated or prevented when the reduction in antithrombin III caused by dilution is prevented by supplementation. Blood from 20 volunteers was divided into four samples. One sample was not diluted and served as control (C). Another was diluted (by 20%) with saline (S). The third was diluted by 20% with saline plus two units of antithrombin (AT III) (SA). The fourth remained undiluted, with two units of added AT III (CA). Coagulation was measured in all four samples using the TEG. In a separate laboratory study, the levels of AT III were measured in control samples and compared with levels after 20% dilution, and 20% dilution with two units of AT III added to the diluent. Enhanced coagulation was demonstrated in saline-diluted samples (S) by shortening of r- and k-times, and increased alpha angle. In the SA samples, r-time shortening was prevented; k-time shortening and alpha-angle increase persisted, but to a reduced degree (difference from saline-only dilution P<0.051). There were no differences between samples C and CA. A predictable drop of AT III (24.2%) occurred with saline dilution, while AT III levels in the AT III/Saline group were similar to the undiluted control. Haemodilution-induced coagulation enhancement is attenuated, but not prevented, if AT III levels are maintained in the normal range. This is in keeping with the established concept of an antithrombin threshold preventing positive coagulation feedback into the intrinsic pathway.
Publication
Journal: Social Psychiatry and Psychiatric Epidemiology
August/17/2009
Abstract
BACKGROUND
Poor social skills are associated with a range of child and adolescent psychiatric disorders, with deficits being particularly marked in autistic spectrum disorders (ASDs). Here, we validate a brief measure of social aptitudes where low scores are designed to index a substantially raised risk of ASDs.
METHODS
Parents of a national community sample of 7,977 British 5-16 year olds completed the Social Aptitudes Scale (SAS) as well as a general questionnaire measure of psychopathology, the Strengths and Difficulties Questionnaire (SDQ). Psychiatric diagnoses were assigned by clinical raters on the basis of detailed multi-informant information.
RESULTS
All ten items of the SAS loaded onto a single latent factor, with a Cronbach's alpha of 0.88. Correlations between the SAS and the SDQ were only modest, suggesting that the SAS measures different attributes to the SDQ. The SAS was significantly better than the SDQ at identifying ASDs.
CONCLUSIONS
Children and adolescents with low SAS scores are at increased risk of mental health problems, particularly ASDs.
Publication
Journal: Autophagy
November/13/2018
Abstract
Flavokawain B (FKB), a natural kava chalcone, displays potent antitumor activity in various types of cancer. The mechanism of action, however, remains unclear. Here, we evaluated the efficacy of FKB in the treatment of human glioblastoma multiforme (GBM) as well as the molecular basis for its inhibitory effects in cancer. Approximately 60% of GBM cells became senescent after treatment with FKB as assessed in the senescence-associated (SA)-GLB1/SA-β-galactosidase assay. The cellular process of autophagy potentially contributed to the establishment of senescence. Transmission electron microscopy revealed the formation of autophagic vesicles under FKB treatment, and MAP1LC3B (microtubule associated protein 1 light chain 3 beta)-II was increased. Transfection of ATG5 or ATG7 small interfering RNAs (siRNAs) inhibited FKB-induced autophagy in U251 cells. Western blot revealed that molecular components of the endoplasmic reticulum stress pathway were activated, including ATF4 (activating transcription factor 4) and DDIT3 (DNA damage inducible transcript 3), while levels of TRIB3 (tribbles pseudokinase 3) increased. In addition, based on the phosphorylation status, the AKT-MTOR-RPS6KB1 pathway was inhibited, which induced autophagy in GBM cells. Inhibition of autophagy by autophagy inhibitors 3-methyladenine and chloroquine or knockdown of ATG5 or ATG7 caused FKB-treated U251 cells to switch from senescence to apoptosis. Finally, knockdown of ATG5 or treatment with chloroquine in combination with FKB, significantly inhibited tumor growth in vivo. Our results demonstrated that FKB induced protective autophagy through the ATF4-DDIT3-TRIB3-AKT-MTOR-RPS6KB1 signaling pathway in GBM cells, indicating that the combination treatment of FKB with autophagy inhibitors may potentially be an effective therapeutic strategy for GBM.
BACKGROUND
3-MA: 3-methyladenine; 4-PBA: 4-phenylbutyrate; AKT: AKT serine/threonine kinase; ATF4: activating transcription factor 4; ATG: autophagy related; CASP3: caspase 3; CCK-8: cell counting kit-8; CDKN1A: cyclin-dependent kinase inhibitor 1A; CQ: chloroquine; DDIT3: DNA damage inducible transcript 3; DMEM: Dulbecco's modified Eagle's medium; EIF2A: eukaryotic translation initiation factor 2A; EIF2AK3: eukaryotic translation initiation factor 2 alpha kinase 3; ER: endoplasmic reticulum; FKB: flavokawain B; GAPDH: glyceraldehyde-3-phosphate dehydrogenase; GBM: glioblastoma multiforme; GFP: green fluorescent protein; HSPA5: heat shock protein family A (Hsp70) member 5; MAP1LC3B: microtubule associated protein 1 light chain 3 beta; MTOR: mechanistic target of rapamycin kinase; PARP1: poly(ADP-ribose) polymerase; 1RPS6KB1: ribosomal protein S6 kinase B1; SA-GLB1: senescence-associated galactosidase beta 1; siRNA: short interfering RNA; SQSTM1: sequestosome 1; TEM: transmission electron microscopy; TRIB3: tribbles pseudokinase 3; TUNEL: deoxynucleotidyl transferase-mediated dUTP nick-end labeling.
Publication
Journal: Journal of Nuclear Medicine
April/23/2007
Abstract
Random bacteriophage (phage) display peptide libraries have traditionally been used for the selection of clones that bind specific tissues, tumors, and antigens. However, once the targeting peptide is synthetically produced, it often displays a lower affinity than the original phage because of a lack of avidity effects and removal from the virion surface. We hypothesized that multivalent bifunctional phage displaying peptides that target novel molecular biomarkers would facilitate the in vivo imaging of cancer. This study provides proof of principle for the use of phage displaying multiple melanocortin-1 receptor-homing peptides for the pretargeting and subsequent imaging of murine melanomas in vivo.
METHODS
A 2-step melanoma pretargeting-imaging system was developed by first generating and biotinylating phage that displayed up to 5 copies of alpha-melanocyte-stimulating hormone (alpha-MSH) peptide analogs. Second, streptavidin was conjugated to diethylenetriaminepentaacetic acid for the purpose of radiolabeling with (111)In.
RESULTS
The specificity of the MSH2.0 phage for the B16-F1 melanoma was demonstrated both in vitro and in vivo. In vitro micropanning assays with phage at inputs of 10(7) and 10(6) transducing units per milliliter resulted in approximately 200- and approximately 1,000-fold-greater recovery of the MSH2.0 phage over the background, respectively. In vivo distribution studies indicated that melanoma uptake values were 2.6 +/- 1.1, 0.6 +/- 0.2, and 1.0 +/- 0.1 (mean +/- SD) percentage injected dose per gram at 0.5, 6, and 24 h after the injection of (111)In-radiolabeled streptavidin ((111)In-SA). The accumulation of radioactivity within the tumor was 1.8 times greater for the biotinylated MSH2.0 phage than for the biotinylated wild-type phage. These data, combined with reduction by 2.4-fold through competition with a nonradiolabeled alpha-MSH peptide analog, indicated the specific targeting of melanoma tumors in vivo. SPECT/CT image analysis of B16-F1 melanoma-bearing mice showed that intravenously injected biotinylated alpha-MSH phage were retained within melanoma tumors at 4 h after injection of (111)In-SA.
CONCLUSIONS
This study demonstrated the use of multivalent bifunctional phage in a 2-step pretargeting-imaging system.
Publication
Journal: Journal of Microbiological Methods
September/25/2006
Abstract
Matrix-assisted laser-desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) has been shown to be a rapid and sensitive method for characterization of bacteria, but it has not yet become a routine microbiological procedure. Currently there are no standardized protocols that would allow development of large libraries of reproducible protein profiles from a broad range of microorganisms to use for identification purposes. Important variables that may affect spectrum quality are MALDI matrices, solvents, cell growth condition, and culture age. In the present study our aim was to: (1) to determine optimal sample preparation and MALDI conditions for discrimination at the strain level; (2) to determine if changes in growth cycle correlated with MALDI spectrum changes; and (3) to compare level of isolate discrimination based on their MALDI spectra versus their 16S rRNA gene sequence. Using 16 strains of the Gram positive bacterium Arthrobacter, optimal spectra were obtained using two-layer sample application of intact cells grown on solid surface overlaid with a matrix consisting of sinapinic acid (SA) or alpha-cyano-hydroxy-cinnaminic acid (CHCA) in 50:50 acetonitrile:water solvent with 2% trifluoroacetic acid. Spectrum changes paralleled the coccus-rod-coccus growth cycle indicative of Arthrobacter. Strain differences based on their MALDI profiles (using Pearson coefficient and UPGMA) corresponded with their 16S rRNA gene phylogeny but it had greater discrimination.
Publication
Journal: Cyberpsychology, Behavior, and Social Networking
September/26/2010
Abstract
Children and adolescents now communicate online to form and/or maintain relationships with friends, family, and strangers. Relationships in "real life" are important for children's and adolescents' psychosocial development; however, they can be difficult for those who experience feelings of loneliness and/or social anxiety. The aim of this study was to investigate differences in usage of online communication patterns between children and adolescents with and without self-reported loneliness and social anxiety. Six hundred twenty-six students ages 10 to 16 years completed a survey on the amount of time they spent communicating online, the topics they discussed, the partners they engaged with, and their purposes for communicating over the Internet. Participants were administered a shortened version of the UCLA Loneliness Scale and an abbreviated subscale of the Social Anxiety Scale for Adolescents (SAS-A). Additionally, age and gender differences in usage of the online communication patterns were examined across the entire sample. Findings revealed that children and adolescents who self-reported being lonely communicated online significantly more frequently about personal and intimate topics than did those who did not self-report being lonely. The former were motivated to use online communication significantly more frequently to compensate for their weaker social skills to meet new people. Results suggest that Internet usage allows them to fulfill critical needs of social interactions, self-disclosure, and identity exploration. Future research, however, should explore whether or not the benefits derived from online communication may also facilitate lonely children's and adolescents' offline social relationships.
Publication
Journal: International Journal of Cancer
June/13/2010
Abstract
Curcumin is a common food ingredient derived from the plant Curcuma longa and is a potent drug against tumorigenesis. Both insulin-like growth factor binding protein-5 (IGFBP-5) and CCAAT/enhancer-binding protein alpha (C/EBPalpha) are suppressors of head and neck carcinogenesis. We identified curcumin as an inducer of IGFBP-5 expression in multiple types of oral keratinocytes; furthermore, curcumin induces IGFBP-5 promoter activity in SAS oral cancer cells. Promoter deletion mapping identified a region (nt -71 to nt -59 relative to the transcription start site) as containing a C/EBPalpha-binding element that is indispensable for curcumin-mediated IGFBP-5 upregulation. Chromatin immunoprecipitation assays revealed that in vivo binding of C/EBPalpha to this region was remarkably increased in the presence of curcumin. Curcumin increased nuclear C/EBPalpha expression and IGFBP-5 expression through p38 activation and this was abrogated by SB203580 treatment. Furthermore, MKK6 expression activated p38 and C/EBPalpha, increasing IGFBP-5 promoter activity and expression. Finally, curcumin-induced IGFBP-5 expression is associated with the suppression of xenograft tumorigenesis in mice due to oral cancer cells. We conclude that curcumin activates p38, which, in turn, activates the C/EBPalpha transactivator by interacting with binding elements in the IGFBP-5 promoter. The consequential upregulation of C/EBPalpha and IGFBP-5 by curcumin is crucial to the suppression of oral carcinogenesis.
Publication
Journal: Immunology
October/23/2007
Abstract
Heterotrimeric G(i) proteins play a role in signalling activated by lipopolysaccharide (LPS), Staphylococcus aureus (SA) and group B streptococci (GBS), leading to production of inflammatory mediators. We hypothesized that genetic deletion of G(i) proteins would alter cytokine and chemokine production induced by LPS, SA and GBS stimulation. LPS-induced, heat-killed SA-induced and heat-killed GBS-induced cytokine and chemokine production in peritoneal macrophages from wild-type (WT), Galpha(i2) (-/-) or Galpha(i1/3) (-/-) mice were investigated. LPS induced production of tumour necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6), IL-10 and interferon-gamma-inducible protein-10 (IP-10); SA induced TNF-alpha, and IL-1beta production; and GBS induced TNF-alpha, IL-6, IL-1beta, macrophage inflammatory protein-1alpha (MIP-1alpha) and keratinocyte chemoattract (KC) production were all decreased (P < 0.05) in Galpha(i2) (-/-) or Galpha(i1/3) (-/-) mice compared with WT mice. In contrast to the role of G(i) proteins as a positive regulator of mediators, LPS-induced production of MIP-1alpha and granulocyte-macrophage colony-stimulating factor (GM-CSF) were increased in macrophages from Galpha(i1/3) (-/-) mice, and SA-induced MIP-1alpha production was increased in both groups of Galpha(i) protein-depleted mice. LPS-induced production of KC and IL-1beta, SA-induced production of GM-CSF, KC and IP-10, and GBS-induced production of IL-10, GM-CSF and IP-10 were unchanged in macrophages from Galpha(i2) (-/-) or Galpha(i1/3) (-/-) mice compared with WT mice. These data suggest that G(i2) and G(i1/3) proteins are both involved and differentially regulate murine inflammatory cytokine and chemokine production in response to both LPS and Gram-positive microbial stimuli.
Publication
Journal: Journal of Vascular Surgery
November/18/1999
Abstract
OBJECTIVE
We have previously shown that fibroblasts cultured from venous ulcers display characteristics of senescence and have reduced growth rates. Susceptibility of young fibroblasts to the microcirculatory changes associated with venous ulcers, such as macrophage trapping and activation, could explain the prevalence of senescent fibroblasts in these wounds.
METHODS
We tested the in vitro effect of venous ulcer wound fluid (VUWF), as well as pro-inflammatory cytokines known to be present in VUWF (TNF-alpha, IL-1beta, and TGF-beta1), on neonatal foreskin fibroblasts (NFFs). NFF growth rates, cellular morphology, and senescence-associated beta-galactosidase (SA-beta-Gal) activity were determined in the presence or absence of VUWF and the above cytokines. VUWF TNF-alpha concentration and the effect of anti-TNF-alpha antibody on VUWF inhibitory activity were determined in samples obtained from four patients with venous ulcers.
RESULTS
NFF growth rates were significantly reduced by VUWF (42,727 +/- 6301 vs 3902 +/- 2191 P =. 006). TNF-alpha also significantly reduced NFF growth rates in a dose-dependent manner (P =.01). No significant growth-inhibitory activity was seen for IL-1alpha or TGF-beta. Incubation with VUWF significantly increased the percentage of SA-beta-Gal-positive fibroblasts in vitro on culture day 12 (P =.02). TNF-alpha and TGF-beta1 had similar effects. TNF-alpha was detected in all VUWF tested, with a mean of 254 +/- 19 pg/mL.
CONCLUSIONS
These data suggest that the venous ulcer microenvironment adversely affects young, rapidly proliferating fibroblasts such as NFFs and induces fibroblast senescence. Pro-inflammatory cytokines such as TNF-alpha and TGF-beta1 might be involved in this process. The role of other unknown inhibitory mediators, as well as pro-inflammatory cytokines, in venous ulcer development and impaired healing must be considered.
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