AR

Distribution by Scientific Domains
Distribution within Medical Sciences

Kinds of AR

  • mutant ar
  • persistent ar

  • Terms modified by AR

  • ar age
  • ar agonist
  • ar allele
  • ar antagonist
  • ar atmosphere
  • ar atom
  • ar dating
  • ar episode
  • ar expression
  • ar gene
  • ar level
  • ar model
  • ar patient
  • ar plasma
  • ar protein
  • ar stimulation

  • Selected Abstracts


    A survey of mobile and wireless technologies for augmented reality systems

    COMPUTER ANIMATION AND VIRTUAL WORLDS (PREV: JNL OF VISUALISATION & COMPUTER ANIMATION), Issue 1 2008
    George Papagiannakis
    Abstract Recent advances in hardware and software for mobile computing have enabled a new breed of mobile augmented reality (AR) systems and applications. A new breed of computing called ,augmented ubiquitous computing' has resulted from the convergence of wearable computing, wireless networking, and mobile AR interfaces. In this paper, we provide a survey of different mobile and wireless technologies and how they have impact AR. Our goal is to place them into different categories so that it becomes easier to understand the state of art and to help identify new directions of research. Copyright © 2008 John Wiley & Sons, Ltd. [source]


    Augmented reality agents for user interface adaptation

    COMPUTER ANIMATION AND VIRTUAL WORLDS (PREV: JNL OF VISUALISATION & COMPUTER ANIMATION), Issue 1 2008
    István Barakonyi
    Abstract Most augmented reality (AR) applications are primarily concerned with letting a user browse a 3D virtual world registered with the real world. More advanced AR interfaces let the user interact with the mixed environment, but the virtual part is typically rather finite and deterministic. In contrast, autonomous behavior is often desirable in ubiquitous computing (Ubicomp), which requires the computers embedded into the environment to adapt to context and situation without explicit user intervention. We present an AR framework that is enhanced by typical Ubicomp features by dynamically and proactively exploiting previously unknown applications and hardware devices, and adapting the appearance of the user interface to persistently stored and accumulated user preferences. Our framework explores proactive computing, multi-user interface adaptation, and user interface migration. We employ mobile and autonomous agents embodied by real and virtual objects as an interface and interaction metaphor, where agent bodies are able to opportunistically migrate between multiple AR applications and computing platforms to best match the needs of the current application context. We present two pilot applications to illustrate design concepts. Copyright © 2007 John Wiley & Sons, Ltd. [source]


    Mixing virtual and real scenes in the site of ancient Pompeii

    COMPUTER ANIMATION AND VIRTUAL WORLDS (PREV: JNL OF VISUALISATION & COMPUTER ANIMATION), Issue 1 2005
    George Papagiannakis
    Abstract This paper presents an innovative 3D reconstruction of ancient fresco paintings through the real-time revival of their fauna and flora, featuring groups of virtual animated characters with artificial-life dramaturgical behaviours in an immersive, fully mobile augmented reality (AR) environment. The main goal is to push the limits of current AR and virtual storytelling technologies and to explore the processes of mixed narrative design of fictional spaces (e.g. fresco paintings) where visitors can experience a high degree of realistic immersion. Based on a captured/real-time video sequence of the real scene in a video-see-through HMD set-up, these scenes are enhanced by the seamless accurate real-time registration and 3D rendering of realistic complete simulations of virtual flora and fauna (virtual humans and plants) in a real-time storytelling scenario-based environment. Thus the visitor of the ancient site is presented with an immersive and innovative multi-sensory interactive trip to the past. Copyright © 2005 John Wiley & Sons, Ltd. [source]


    The virtual interaction panel: an easy control tool in augmented reality systems

    COMPUTER ANIMATION AND VIRTUAL WORLDS (PREV: JNL OF VISUALISATION & COMPUTER ANIMATION), Issue 3-4 2004
    M. L. Yuan
    Abstract In this paper, we propose and develop an easy control tool called Virtual Interaction Panel (VirIP) for Augmented Reality (AR) systems, which can be used to control AR systems. This tool is composed of two parts: the design of the VirIPs and the tracking of an interaction pen using a Restricted Coulomb Energy (RCE) neural network. The VirIP is composed of some virtual buttons, which have meaningful information that can be activated by an interaction pen during the augmentation process. The interaction pen is a general pen-like object with a certain color distribution. It is tracked using a RCE network in real-time and used to trigger the VirIPs for AR systems. In our system, only one camera is used for capturing the real world. Therefore, 2D information is used to trigger the virtual buttons to control the AR systems. The proposed method is real-time because the RCE-based image segmentation for a small region is fast. It can be used to control AR systems quite easily without any annoying sensors attached to entangling cables. This proposed method has good potential in many AR applications in manufacturing, such as assembly without the need for object recognition, collaborative product design, system control, etc. Copyright © 2004 John Wiley & Sons, Ltd. [source]


    Experience of trauma and conversion to psychosis in an ultra-high-risk (prodromal) group

    ACTA PSYCHIATRICA SCANDINAVICA, Issue 5 2010
    A. Bechdolf
    Bechdolf A, Thompson A, Nelson B, Cotton S, Simmons MB, Amminger GP, Leicester S, Francey SM, McNab C, Krstev H, Sidis A, McGorry PD, Yung AR. Experience of trauma and conversion to psychosis in an ultra-high-risk (prodromal) group. Objective:, We aimed to replicate a recent finding of high prevalence of trauma history in patients at ,ultra-high risk' (UHR) of psychotic disorder and to investigate whether trauma predicts conversion to psychosis in this population. Method:, A consecutive sample of UHR patients was assessed. History of trauma was accessed with the General Trauma Questionnaire. Cox regression models were used to explore relationship between conversion to psychosis and trauma. Results:, Of 92 UHR patients nearly 70% had experienced a traumatic event and 21.7% developed psychosis during follow-up (mean 615 days). Patients who had experienced a sexual trauma (36%) were significantly more likely to convert to first-episode psychosis (OR 2.96) after controlling for meeting multiple UHR intake groups. Conclusion:, UHR patients have a high prevalence of history of trauma. Previous sexual trauma may be a predictor of onset of psychotic disorder in this population. [source]


    Egg and sperm recognition systems during fertilization

    DEVELOPMENT GROWTH & DIFFERENTIATION, Issue 2008
    Noritaka Hirohashi
    Fertilization is a programmed process that has many molecules and sequential events amenable to study. The biochemistry of fertilization has identified cellular and acellular components fundamental to the interactions between sperm and egg. Recent studies highlight the molecular details of the species-specificity of fertilization that involve protein,protein and protein,carbohydrate interactions. Although the diversity of structure and mechanism may imply rapid evolution of fertilization proteins, understanding the structure,function relationships has become important. Here, we introduce the molecules controlling the sperm AR, sperm attachment to, and penetration through, the egg investments. [source]


    Motherless rats show deficits in maternal behavior towards fostered pups

    DEVELOPMENTAL PSYCHOBIOLOGY, Issue 2 2010
    Daniela J. Palombo
    Abstract Complete maternal deprivation in rats, through artificial rearing (AR), produces deficits in subsequent maternal behavior of the offspring. These deficits are partially reversed when isolated pups are provided with additional tactile stimulation designed to simulate maternal licking (e.g., Gonzalez et al. [2001] Developmental Psychobiology, 38, 11,32). These findings highlight the importance of the early maternal environment in subsequent development. However, given the possibility that prenatal environments may differ between AR and maternally reared (MR) offspring, the deficits in the behavior of AR mothers may be driven by the characteristics of their pups derived from the effects of an altered prenatal environment. Hence differences in the neonatal pups of AR mothers may produce the alterations in the AR maternal behavior. To rule out this possibility, we employed a fostering paradigm where AR and MR mothers received cross-fostered mother-reared pups. AR mothers showed the same level of deficits in maternal behavior towards MR foster pups as they do with their own pups and these deficits were partially reversed with additional tactile stimulation. Hence, maternal behavior deficits reported in mothers who had been reared in isolation are due primarily to the direct effects of the earlier experience on mechanisms regulating their maternal behavior and not to the effects on their offspring. © 2010 Wiley Periodicals, Inc. Dev Psychobiol 52:142,148, 2010 [source]


    Artificial rearing alters the response of rats to natural and drug-mediated rewards

    DEVELOPMENTAL PSYCHOBIOLOGY, Issue 4 2006
    Anna M. Lomanowska
    Abstract Artificial rearing (AR) of infant rats permits precise control over key features of the early environment without maternal influence. The present study examined the behavioral response of AR rats towards natural and drug-mediated rewards, as well as their exploratory and affective behaviors. Adolescent AR rats showed increased preference for sucrose consumption relative to chow and demonstrated greater activity in the open field and in the elevated plus-maze compared to maternally reared (MR) rats. With respect to measures of emotionality, AR rats showed enhanced avoidance of the open arms of the plus-maze, indicating increased anxiety, but they did not differ from MR rats in exploring the center of the open field. Adult AR rats displayed a stronger conditioned response to morphine in a place preference test. These findings support the potential of the AR model to contribute to understanding the role of early experience in the development of behavioral motivation. © 2006 Wiley Periodicals, Inc. Dev Psyshobiol 48: 301,314, 2006. [source]


    Maternal and littermate deprivation disrupts maternal behavior and social-learning of food preference in adulthood: Tactile stimulation, nest odor, and social rearing prevent these effects

    DEVELOPMENTAL PSYCHOBIOLOGY, Issue 3 2006
    Angel I. Melo
    Abstract Maternal and littermate (social) separation, through artificial rearing (AR), disrupts the development of subsequent maternal behavior and social learning in rats. The addition of maternal-licking-like stimulation during AR, partially reverses some of these effects. However, little is know about the role of social stimuli from littermates and nest odors during the preweaning period, in the development of the adult maternal behavior and social learning. The purpose of this study was to examine the effects of peer- and peer-and-odor rearing on the development of maternal behavior and social learning in rats. Female pups were reared with mothers (mother reared,MR) or without mothers (AR) from postnatal day (PND) 3. AR rats received three different treatments: (1) AR-CONTROL group received minimal tactile stimulation, (2) AR-ODOR females received exposure to maternal nest material inside the AR-isolation-cup environment, (3) AR-SOCIAL group was reared in the cup with maternal nest material and a conspecific of the same-age and same-sex and received additional tactile stimulation. MR females were reared by their mothers in the nest and with conspecifics. In adulthood, rats were tested for maternal behavior towards their own pups and in a social learning task. Results confirm our previous report that AR impairs performance of maternal behavior and the development of a social food preference. Furthermore, social cues from a littermate, in combination with tactile stimulation and the nest odor, reversed the negative effects of complete isolation (AR-CONTROL) on some of the above behaviors. Exposure to the odor alone also had effects on some of these olfactory-mediated behaviors. These studies indicate that social stimulation from littermates during the preweaning period, in combination with odor from the nest and tactile stimulation, contributes to the development of affiliative behaviors. © 2006 Wiley Periodicals, Inc. Dev Psyshobiol 48: 209,219, 2006. [source]


    Cataracts in experimentally diabetic mouse: morphological and apoptotic changes

    DIABETES OBESITY & METABOLISM, Issue 2 2005
    K. R. Hegde
    Aim:, The objective of these investigations was to extend our earlier study on the induction of cataracts in diabetic mice, a low aldose reductase (AR) animal model at morphological level. Previous studies were done primarily at biochemical level. Methods:, Diabetes was induced by intraperitoneal administration of streptozotocin. The lenses isolated after the establishment of diabetes were then subjected to histologic and electron microscopic studies. Results:, Morphological alterations were characterized by shrinkage, elongation and lobulization of the nuclei of the epithelial cells. This was associated with chromatin condensation and its margination. Similar structural aberrations were also observed in a significant number of the subepithelial fibre cells representing defect in fibre maturation. More interestingly, unlike that in other common animal models of diabetic cataract, such abnormally nucleated cells were also found to be prevalent in the posterior subcapsular region, a finding common in human diabetics also. Conclusion:, The present studies further affirm the suitability of the mouse model for a study of cataractogenesis induced by diabetes. Because of the findings reported herein, as well as the known biochemical similarity between the lenses of the mice and humans in respect of AR deficiency, contrary to the rat model where it is very high, use of this species is considered more useful towards understanding the basic aetiology as well as for evaluating the efficacy of various referred nutritional and metabolic antioxidants against such cataracts. [source]


    Aldose reductase gene is associated with diabetic macroangiopathy in Japanese Type 2 diabetic patients

    DIABETIC MEDICINE, Issue 8 2006
    A. Watarai
    Abstract Aims The aldose reductase (AR) gene, a rate-limiting enzyme of the polyol pathway, has been investigated as a candidate gene in determining susceptibility to diabetic microangiopathy. However, the association of the AR gene with diabetic macroangiopathy has not been investigated. Therefore, the present study was conducted to determine whether genetic variations of AR may determine susceptibility to diabetic macroangiopathy. Methods There were 378 Type 2 diabetic patients enrolled in this study. A single nucleotide polymorphism in the promoter region (C-106T) was genotyped and the AR protein content of erythrocytes measured by ELISA. Results There were no significant differences in genotypic or allelic distribution in patients with or without ischaemic heart diseases, but there was a significant increase in the frequency of the CT + TT genotype and T allele in patients with stroke (P = 0.019 and P = 0.012). The erythrocyte AR protein content was increased in patients with the CT and TT genotype compared with those with the CC genotype. After adjustment for age, duration of diabetes, body mass index, systolic blood pressure, HbA1c, and serum creatinine, triglycerides, and total cholesterol in multivariate logistic-regression models, the association between this AR genotype and stroke remained significant. Conclusions Our results suggest that the CT or TT genotype of the AR gene might be a genetic marker of susceptibility to stroke in Type 2 diabetic patients. This observation might contribute to the development of strategies for the prevention of stroke in Type 2 diabetic patients. [source]


    Central fat predicts deterioration of insulin secretion index and fasting glycaemia: 6-year follow-up of subjects at varying risk of Type 2 diabetes mellitus

    DIABETIC MEDICINE, Issue 4 2003
    A. D. Kriketos
    Abstract Aims To examine the relationships between body composition and changes in fasting glycaemia, and in indices of insulin secretion and insulin action over 6 years in females with a family history of Type 2 diabetes with or without prior gestational diabetes (,at risk' group, AR) and control females (control group, C). Methods At baseline and at follow-up, an oral glucose tolerance test and dual energy X-ray absorptiometry assessment of body composition were performed. Indices of insulin resistance (HOMA R,) and insulin secretion (HOMA ,,) were obtained from fasting insulin and glucose concentrations. Results At baseline, the groups were similar for age, body mass index, fasting levels of plasma glucose and insulin, HOMA R, and HOMA ,,. Despite similar total body fatness, AR had significantly greater waist circumference and central fat (both P < 0.02) compared with C. At follow-up there was a significant increase in central adiposity only in AR, and the fasting plasma glucose (FPG) level was higher in AR compared with C (5.0 ± 0.2 vs. 4.3 ± 0.2 mmol/l, P = 0.02). This rise in plasma glucose in AR was related to a decline in HOMA ,, (r = 0.45, P = 0.0065). Both the baseline and the increments in total and central abdominal fat mass were associated with the time-related decline in HOMA ,,. Conclusions Six years after initial assessment, AR showed deterioration in FPG levels due predominantly to a decline in insulin secretion index without major change in insulin resistance index. Importantly, baseline body fatness (especially central adiposity), as well as increases in fatness with time, were the major predictors of the subsequent decline of insulin secretion index and the consequent rise in FPG. [source]


    Evaluation of a training program to improve clinicians' assessment of patient stability

    DRUG AND ALCOHOL REVIEW, Issue 4 2009
    ADAM R. WINSTOCK
    Abstract Introduction and Aims. Public clinics in New South Wales (NSW), Australia play a central role in inducting and stabilising opioid dependent clients onto treatment before transfer to a community pharmacy. Clinical assessment of stability is a vital skill in ensuring that clients are appropriately and effectively transferred. A two-hour clinical training program was delivered to staff at 31 public clinics, that aimed to improve staff confidence in assessing client stability, and skills in negotiating the transfer of clients to community pharmacies. Design and Methods. Pre- and post-training evaluation was conducted examining self-ratings of confidence and ability in the assessment of client stability, and the perceived utility of a clinical algorithm to improve assessments. Follow-up was conducted 3 to 6 months post-training assessing individual and clinic level changes in clinical practice. Results. 205 staff completed pre- and post-training questionnaires. Staff demonstrated a moderate level of self-reported baseline knowledge and skills in assessing client stability (mean = 6.5; 1 = poor; 10 = excellent) that improved when re-assessed following the training (mean = 8.0). 76 staff responded to the follow-up questionnaire. , 75% reported some level of improvement in their approach to clinical practice regarding stability assessment, and 59% reported being more effective in identifying clients appropriate for community pharmacy transfer. Of 19 public clinics, 14 reported an increased focus on stability assessment. Nine clinics reported barriers to achieving changes in clinical practice. Discussion and Conclusions. This evaluation demonstrates that it is possible to implement a targeted clinical training package to staff that translates into positive changes in clinical practice.[Winstock AR, Lea T. Evaluation of a training program to improve clinicians' assessment of patient stability. Drug Alcohol Rev 2009;28:353,359] [source]


    Development of fluridil, a topical suppressor of the androgen receptor in androgenetic alopecia

    DRUG DEVELOPMENT RESEARCH, Issue 3 2003
    Allen L Seligson
    Abstract Nonsteroidal antiandrogens (AA) cannot be topically used for androgenetic alopecia (AGA) because of systemic resorption. A new class of androgen receptor (AR) suppressors designed for safe topical treatment of AGA was synthesized from (3-amino-2-hydroxy-2-methyl- N -(4-nitro-3-trifluoromethyl)phenyl) propanamide (BP-34), to contain perfluoroalkyl moieties. The trifluoromethyl derivative (fluridil) at 10 ,M decreased expression of the AR in LNCaP human cells by 95%, its serum half-life was 6 h; it decomposes hydrolytically to BP-34 and trifluoroacetic acid. Acute intraperitoneal maximum tolerated dose (MTD) of fluridil in mice is 270,300 mg/kg/d and the subacute MTD is 450 mg/kg/d. The oral LD50 in mice was 2,872 mg/kg in males, 2,232 mg/kg in females, and >2,500 mg/kg in rats. Fluridil solution in isopropanol was not cutaneously absorbed in rabbits, did not sensitize or show any phototoxic or photoallergic effects on guinea pig skin, and demonstrated no skin irritation potential in rabbits and humans. Fluridil solid induced only slight and reversible eye irritancy in rabbits and displayed no cytotoxicity to rabbit corneal fibroblasts in vitro. Fluridil demonstrated no significant mutagenicity potential by Ames method. In a double-blind study, 43 males with AGA, Norwood grade II to Va, used topical 2% fluridil in isopropanol or the vehicle daily for 12 months. Anagens (growing hairs) increased in the fluridil group from 76% to 89%. All hematological and biochemistry values remained within normal range, including testosterone, which varied but seasonally. No fluridil or its decomposition product (BP-34) was detected in serum. No adverse side effects were reported. Drug Dev. Res. 59:292,306, 2003. © 2003 Wiley-Liss, Inc. [source]


    Relationship between Left Ventricular Geometry and Left Ventricular Systolic and Diastolic Functions in Patients with Chronic Severe Aortic Regurgitation

    ECHOCARDIOGRAPHY, Issue 6 2008
    Murat Çayli M.D.
    Background: Chronic aortic regurgitation (AR) is a form of volume overload inducing left ventricle (LV) dilatation. Myocardial fibrosis, apoptosis, progressive LV dilatation, and eventually LV dysfunction are seen with the progression of disease. The aim of the study was to assess the relation between LV geometry and LV systolic and diastolic functions in patients with chronic severe AR. Methods: The study population consisted of 88 patients with chronic severe AR and 42 healthy controls. The LV ejection fraction (LVEF) was calculated. Subjects were divided as Group I (controls, n = 42), Group II (LVEF > 50%, n = 47), and Group III (LVEF < 50%, n = 41). Transmitral early and late diastolic velocities and deceleration time were measured. The annular systolic (Sa) and diastolic (Ea and Aa) velocities were recorded. Diastolic function was classified as normal, impaired relaxation (IR), pseudonormalization (PN), and restrictive pattern (RP). Results: The LVEF was similar in Group I and II, while significantly lower in Group III. Sa velocity was progressively decreasing, but LV long- and short-axis diameters were increasing from Group I to Group III. Forty-six, 31 and 11 patients had IR, PN, and RP, respectively. LV long-axis systolic and diastolic diameters were significantly increasing, while LVEF and Sa velocity were significantly decreasing from patients with IR to patients with RP. The LV long-axis diastolic diameter is independently associated with LV systolic and diastolic functions. Conclusions: The LV long-axis diastolic diameter is closely related with LV systolic and diastolic functions in patients with chronic severe AR. [source]


    A Larger Aortic Annulus Causes Aortic Regurgitation and a Smaller Aortic Annulus Causes Aortic Stenosis in Bicuspid Aortic Valve

    ECHOCARDIOGRAPHY, Issue 3 2008
    Makoto Sonoda M.D.
    A bicuspid aortic valve (BAV) often causes aortic stenosis (AS) or regurgitation (AR). In 54 patients with a BAV (48 ± 16 years), transthoracic and transesophageal echo were performed to measure aortic annulus diameter (AAD), to evaluate the severity of aortic valve disease (AVD) and to calculate the area eccentricity index (AEI) of a BAV defined as a ratio of the larger aortic cusp area to a smaller aortic cusp area. By multiple linear regression analysis, the severity of AR correlated significantly with the AAD (r = 0.38) and AEI (r = 0.35) (P < 0.05) and that of AS correlated significantly with the AAD (r =,0.40) and AEI (r = 0.34) (P < 0.05). Thirty-six patients showed anteroposteriorly (A-P) located BAVs and 18 patients showed right-left (R-L) located BAVs. The AAD was larger in A-P type than in R-L type (15 ± 3 vs 13 ± 2 mm/BSA, P < 0.05) and there was no difference in the age and AEI between the two groups. AR was more severe in A-P type than in R-L type while AS was more severe in R-L type than in A-P type (P < 0.05). Twenty-nine patients showed raphes. The AEI was larger in raphe (+) type than in raphe (,) type (1.83 ± 0.53 vs 1.51 ± 0.47, P < 0.05) and there was no difference in the AAD and severity of AVD between the two groups. In conclusion, a BAV with larger aortic annulus or A-P located will tend to cause AR while a BAV with smaller aortic annulus or R-L located will tend to cause AS. [source]


    Effect of di(n -butyl) phthalate on testicular oxidative damage and antioxidant enzymes in hyperthyroid rats

    ENVIRONMENTAL TOXICOLOGY, Issue 3 2007
    Ena Lee
    Abstract This study compared the effects of di(n-butyl) phthalate (DBP) on the oxidative damage and antioxidant enzymes activity in testes of hyperthyroid rats. Hyperthyroidism was induced in pubertal male rats by intraperitoneal injection of triiodothyronine (T3, 10 ,g/kg body weight) for 30 days. An oral dose of DBP (750 mg/kg) was administered simultaneously to normal or hyperthyroid (T3) rats over a 30-day period. No changes in body weight were observed in the hyperthyroid groups (T3, T3 + DBP) compared with controls. There were significantly higher serum T3 levels observed in the hyperthyroid rats than in the control, but the serum thyroid stimulating hormone levels were markedly lower in the hyperthyroid rats. DBP significantly decreased the weight of the testes in the normal (DBP) and hyperthyroid (T3 + DBP) groups. The serum testosterone concentrations were significantly lower in only DBP group. DBP significantly increased the 8-hydroxy-2-deoxyguanosine (8-OHdG) level in the testes, whereas the DBP-induced 8-OHdG levels were slightly higher in T3 + DBP group. Superoxide dismutase and glutathione peroxidase activities were significantly higher in the testes of the DBP or T3 + DBP groups. Catalase (CAT) activity was significantly higher in the DBP treatment group, but the T3 + DBP group showed slightly lower DBP-induced CAT activity. The testicular expression of thyroid hormone receptor ,-1 (TR,-1) was significantly higher in the DBP groups, and androgen receptor (AR) expression was not detected in the DBP treatment group. In addition, DBP significantly increased the peroxisome proliferator-activated receptor-r (PPAR-r) levels in the testis. These results suggest that hyperthyroidism can cause a change in the expression level of PPAR-r in testes, and may increase the levels of oxidative damage induced by the metabolic activation of DBP. © 2007 Wiley Periodicals, Inc. Environ Toxicol 22: 245,255, 2007. [source]


    Advanced fluorescence in situ hybridization to localize and quantify gene expression in Japanese medaka (Oryzias latipes) exposed to endocrine-disrupting compounds

    ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 9 2009
    June-Woo Park
    Abstract In an earlier study, we described the development of fluorescence in situ hybridization (FISH) using confocal microscopy to localize and quantify gene expression in fish. Here, we report the results of FISH application to investigate effects of model endocrine-disrupting chemicals (EDCs), 17,-ethinylestradiol (EE2) and 17,-trenbolone (TB), on expressions of EDC-responsive genes in Japanese medaka (Oryzias latipes) at the cellular/tissue level paired with histological observation. Gene expressions of vitellogenin-II (Vit-II), androgen receptor (AR), and cytochrome P450 gonadal aromatase (CYP19a) were determined after exposure to 5, 50, or 500 ng/L of EE2 or 50, 500, or 5,000 ng/L of TB for 7 d. Exposure to the greatest concentration of EE2 or TB significantly reduced fecundity and caused histological alterations in gonads. 17,-Ethinylestradiol induced Vit-II expression in both male gonads and liver relative to controls and resulted in greater intensity of hematoxylin staining in hepatocytes, which was significantly correlated with Vit-II induction in liver. When exposed to EE2 at less than 50 ng/L, CYP19a expression associated with early stage oocytes was greater than that in controls. However, at 500 ng/L, this trend was reversed. The greater Vit-II expression in testis from all EE2 groups, and the lesser expression of CYP19a in ovaries from the 500 ng/L group, likely is related to changes in the number of cells in which these genes are predominantly expressed rather than to an increase in expression per cell. 17,-Trenbolone significantly induced AR expression in ovaries but did not alter AR expression in female liver. It was concluded that FISH combined with histology enables advanced elucidation of molecular effects of chemicals by associating changes in gene expression with certain tissues and/or cell types and allows these changes to be related to histological effects. [source]


    Toxicokinetics of perfluorocarboxylate isomers in rainbow trout

    ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 2 2009
    Amila O. De Silva
    Abstract Perfluorooctanoate (PFOA) and other perfluorocarboxylates (PFCAs) are widely dispersed in the environment. Current and/or historical production of PFOA and fluorochemical precursors was conducted by telomerization and electrochemical fluorination (ECF). Telomer products typically contain linear chains of perfluorocarbons, and ECF products are a mixture of linear and branched isomers. The objective of the present study was to examine the role of toxicokinetics on PFCA isomer profiles in fish since monitoring studies have revealed a predominance of n -isomers of PFCAs in biota. Using dietary exposure, rainbow trout were administered technical ECF PFOA isomers (6.9 ,g/kg/d), linear perfluorononanoate (1.4 ,g/kg/d n -PFNA), and isopropyl PFNA (1.1 ,g/kg/d iso -PFNA) for 36 d and then switched to a 40-d clean diet. Throughout exposure and depuration phases, blood and tissue sampling ensued. The accumulation ratio (AR) revealed similar accumulation propensity of n -PFOA and two minor branched PFOA isomers; however, the majority of branched isomers had lower AR values than n -PFOA. Enrichment of n -PFOA and n -PFNA relative to most branched isomers was consistent in all tissues. First-order elimination (kd) and half-life (t1/2) values were calculated. The largest t1/2 corresponded to n -PFNA followed by iso -PFNA. In ECF PFOA isomers, both n -PFOA and one minor branched isomer had the largest t1/2, suggesting that this minor isomer could be diagnostic of ECF exposure using environmental PFOA isomer patterns. Results of lower-dose ECF PFOA exposure showed similar results to the high-dose study; it is possible that both scenarios resulted in saturation of processes involved in PFCA transport. As such, the toxicokinetics of PFCA isomers at environmentally realistic levels may deviate from the results of the present study. [source]


    Attentional re-training decreases attentional bias in heavy drinkers without generalization

    ADDICTION, Issue 3 2007
    Tim Schoenmakers
    ABSTRACT Aims To examine whether alcohol-related attentional bias (AB) can be reduced by training heavy drinkers to attend to soft drinks as an alternative to alcohol. Diminishing AB is important because AB has been suggested to be a significant factor in the development, maintenance and relapse of addictive behaviours. AB was trained in a clinically relevant design, and we studied the generalization of this training. Design, participants and intervention We assigned randomly 106 heavy drinking male college and university students to the attentional re-training (AR; modified visual-probe task) or control condition (standard visual-probe task). Setting Laboratory at Maastricht University. Measurements We measured the effects of AR on the visual-probe task with stimuli that were presented in the AR and with new stimuli, and on an alternative measure of AB, the flicker paradigm. We further measured effects on craving and preference for either an alcohol beverage or a soft drink. Findings After AR, participants had learned to avoid alcohol stimuli and had developed an AB for soft drinks. This effect was restricted to stimuli used in the AR. The flicker task, where AB for alcohol was found in both the AR and control groups, was not affected by the AR. No effect was found on craving and the preference task. Conclusions Although heavy drinkers can learn to attend selectively to an alternative category for alcohol, a single AR is not sufficient to decrease symptoms of problem drinking. [source]


    Modeling monthly temperature data in Lisbon and Prague

    ENVIRONMETRICS, Issue 7 2009
    Teresa Alpuim
    Abstract This paper examines monthly average temperature series in two widely separated European cities, Lisbon (1856,1999) and Prague (1841,2000). The statistical methodology used begins by fitting a straight line to the temperature measurements in each month of the year. Hence, the 12 intercepts describe the seasonal variation of temperature and the 12 slopes correspond to the rise in temperature in each month of the year. Both cities show large variations in the monthly slopes. In view of this, an overall model is constructed to integrate the data of each city. Sine/cosine waves were included as independent variables to describe the seasonal pattern of temperature, and sine/cosine waves multiplied by time were used to describe the increase in temperature corresponding to the different months. The model also takes into account the autoregressive, AR(1), structure that was found in the residuals. A test of the significance of the variables that describe the variation of the increase in temperature shows that both Lisbon and Prague had an increase in temperature that is different according to the month. The winter months show a higher increase than the summer months. Copyright © 2009 John Wiley & Sons, Ltd. [source]


    Testing for trends in the violation frequency of an environmental threshold in rivers

    ENVIRONMETRICS, Issue 1 2009
    Lieven Clement
    Abstract Nutrient pollution in rivers is a common problem. It can provoke algae blooms which are related to increased fish mortality. To restore the water status, the regulator recently has promulgated more restrictive regulations. In Flanders for instance, the government has introduced several manure decrees (MDs) to restrict nutrient pollution. Environmental regulations are commonly expressed in terms of threshold levels. This provides a binary response to the decision maker. To handle such data, we propose the use of marginalised generalised linear mixed models. They provide valid inference on trends in the exceedance frequency. The spatio-temporal dependence of the river monitoring network is incorporated by the use of a latent variable. The temporal dependence is assumed to be AR(1) and the spatial dependence is derived from the river topology. The mean model contains a term for the trend and corrects for seasonal variation. The model formulation allows an assessment on the level of individual sampling locations and on a more regional scale. The methodology is applied to a case study on the river Yzer (Flanders). It assesses the impact of the MDs on the violation probability of the nitrate standard. A trend change is detected after the introduction of the second MD. Copyright © 2008 John Wiley & Sons, Ltd. [source]


    Space,time zero-inflated count models of Harbor seals,

    ENVIRONMETRICS, Issue 7 2007
    Jay M. Ver Hoef
    Abstract Environmental data are spatial, temporal, and often come with many zeros. In this paper, we included space-time random effects in zero-inflated Poisson (ZIP) and ,hurdle' models to investigate haulout patterns of harbor seals on glacial ice. The data consisted of counts, for 18 dates on a lattice grid of samples, of harbor seals hauled out on glacial ice in Disenchantment Bay, near Yakutat, Alaska. A hurdle model is similar to a ZIP model except it does not mix zeros from the binary and count processes. Both models can be used for zero-inflated data, and we compared space-time ZIP and hurdle models in a Bayesian hierarchical model. Space-time ZIP and hurdle models were constructed by using spatial conditional autoregressive (CAR) models and temporal first-order autoregressive (AR(1)) models as random effects in ZIP and hurdle regression models. We created maps of smoothed predictions for harbor seal counts based on ice density, other covariates, and spatio-temporal random effects. For both models predictions around the edges appeared to be positively biased. The linex loss function is an asymmetric loss function that penalizes overprediction more than underprediction, and we used it to correct for prediction bias to get the best map for space-time ZIP and hurdle models. Published in 2007 by John Wiley & Sons, Ltd. [source]


    Contending with space,time interaction in the spatial prediction of pollution: Vancouver's hourly ambient PM10 field

    ENVIRONMETRICS, Issue 5-6 2002
    Jim Zidek
    Abstract In this article we describe an approach for predicting average hourly concentrations of ambient PM10 in Vancouver. We know our solution also applies to hourly ozone fields and believe it may be quite generally applicable. We use a hierarchical Bayesian approach. At the primary level we model the logarithmic field as a trend model plus Gaussian stochastic residual. That trend model depends on hourly meteorological predictors and is common to all sites. The stochastic component consists of a 24-hour vector response that we model as a multivariate AR(3) temporal process with common spatial parameters. Removing the trend and AR structure leaves ,whitened' time series of vector series. With this approach (as opposed to using 24 separate univariate time series models), there is little loss of spatial correlation in these residuals compared with that in just the detrended residuals (prior to removing the AR component). Moreover our multivariate approach enables predictions for any given hour to ,borrow strength' through its correlation with adjoining hours. On this basis we develop a spatial predictive distribution for these residuals at unmonitored sites. By transforming the predicted residuals back to the original data scales we can impute Vancouver's hourly PM10 field. Copyright © 2002 John Wiley & Sons, Ltd. [source]


    Autosomal Recessive Idiopathic Epilepsy in an Inbred Family from Turkey: Identification of a Putative Locus on Chromosome 9q32-33

    EPILEPSIA, Issue 5 2004
    Betül Baykan
    Summary: Purpose: The study describes the clinical features of an inbred family from Turkey with three members affected by seizures and tests possible autosomal recessive (AR) inheritance by means of linkage analysis. Methods: Personal and family history was obtained from each subject, and general physical, neurologic, and EEG examinations were performed. A set of 382 fluorescence-labeled markers was used for the initial genome-wide search. A further set of 83 markers was used to map the locus precisely and to exclude the remaining genome. Results: Twelve individuals from three generations were examined. Two subjects were affected by idiopathic epilepsy, whereas, their brother experienced a single unprovoked generalized seizure. Two siblings affected by idiopathic epilepsy and their unaffected sister showed a photoparoxysmal response to photic stimulation. Nine family members reported migraine. The genome-wide search led to the identification of a unique homozygous, 15.1-cM region shared by subjects with seizures on chromosome 9q32-33 and providing a lod score of 2.9. This locus, however, was not associated with migraine in this pedigree. Conclusions: The study suggests that idiopathic epileptic traits with AR inheritance might be underestimated in the general population and that inbred pedigrees may represent powerful tools for the identification of AR genes. [source]


    Nasal nitric oxide measurements before and after repeated humming maneuvers

    EUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 12 2003
    M. Maniscalco
    Abstract Background, It has been recently shown that humming greatly increases nasal nitric oxide (NO). This is most likely owing to a rapid washout of sinus NO caused by the oscillating sound waves. During repeated humming manoeuvres nasal NO gradually decreases, likely because NO accumulated in the sinuses is washed out. Aim, We studied whether humming before measurements would affect nasally exhaled NO. Materials and methods, NO output was measured by the chemiluminescence technique in orally and nasally exhaled air in 38 subjects: 18 healthy subjects (HS), 15 subjects with allergic rhinitis (AR) and five subjects with allergic nasal polyposis (AP). Each subject performed a NO measurement during quiet nasal exhalation either preceded by a period of silence/free speaking or immediately after five consecutive humming manoeuvres (posthumming). Results, Mean nasal NO output (95% CI) after a period of silence/free speaking was 231 nL min,1 (178,284) in HS, 434 nL min,1 (347,522) in AR (P < 0·001) and 262 nL min,1 (163,361) in AP. Post-humming nasal NO output was 16% (5 to 50%) lower in HS and 14% (1 to 49%) lower in AR, while it remained unchanged in AP subjects. Intra-subject coefficient of variation of quiet nasal exhalation was 12% in HS, 13% in AR and 5% in AP. Post humming intraindividual coefficient of variation significantly decreased in both HS and AR, but it did not change in AP. Conclusions, Nasal NO levels measured immediately after repeated humming manoeuvres are consistently lower and more reproducible than nasal NO levels measured after a period of silence or free speaking. Repeated humming effectively empties the sinuses, thereby probably minimizing the normal contribution from the sinuses to nasal NO. This may be useful to better estimate NO output from the nasal cavity mucosa in health and disease. [source]


    Cannabinoid modulation of limbic forebrain noradrenergic circuitry

    EUROPEAN JOURNAL OF NEUROSCIENCE, Issue 2 2010
    Ana F. Carvalho
    Abstract Both the endocannabinoid and noradrenergic systems have been implicated in neuropsychiatric disorders. Importantly, low levels of norepinephrine are seen in patients with depression, and antagonism of the cannabinoid receptor type 1 (CB1R) is able to induce depressive symptoms in rodents and humans. Whether the interaction between the two systems is important for the regulation of these behaviors is not known. In the present study, adult male Sprague,Dawley rats were acutely or chronically administered the CB1R synthetic agonist WIN 55,212-2, and ,2A and ,1 adrenergic receptors (AR) were quantified by Western blot. These AR have been shown to be altered in a number of psychiatric disorders and following antidepressant treatment. CB1R agonist treatment induced a differential decrease in ,2A- and ,1-ARs in the nucleus accumbens (Acb). Moreover, to assess long-lasting changes induced by CB1R activation, some of the chronically treated rats were killed 7 days following the last injection. This revealed a persistent effect on ,2A-AR levels. Furthermore, the localization of CB1R with respect to noradrenergic profiles was assessed in the Acb and in the nucleus of the solitary tract (NTS). Our results show a significant topographic distribution of CB1R and dopamine beta hydroxylase immunoreactivities (ir) in the Acb, with higher co-localization observed in the NTS. In the Acb, CB1R-ir was found in terminals forming either symmetric or asymmetric synapses. These results suggest that cannabinoids may modulate noradrenergic signaling in the Acb, directly by acting on noradrenergic neurons in the NTS or indirectly by modulating inhibitory and excitatory input in the Acb. [source]


    ,2A and ,2C -adrenoceptor regulation in the brain: ,2A changes persist after chronic stress

    EUROPEAN JOURNAL OF NEUROSCIENCE, Issue 5 2003
    G. Flügge
    Abstract Stress-induced activation of the central nervous noradrenergic system has been suspected to induce depressive disorders. As episodes of depression often occur some time after a stress experience we investigated whether stress-induced changes in the ,2 -adrenoceptor (,2 -AR) system persist throughout a post-stress recovery period. Brains of male tree shrews were analysed after 44 days of chronic psychosocial stress and after a subsequent 10-day recovery period. Expression of RNA for ,2A and ,2C -adrenoceptors was quantified by in situ hybridization, and receptor binding was determined by in vitro receptor autoradiography. Activities of the sympathetic nervous system and of the hypothalamo,pituitary,adrenal axis were increased during chronic stress but normalized during recovery. ,2A -AR RNA in the glutamatergic neurons of the lateral reticular nucleus was elevated significantly after stress and after recovery (by 29% and 17%). In the dorsal motor nucleus of the vagus, subtype A expression was enhanced after recovery (by 33%). In the locus coeruleus, subtype A autoreceptor expression was not changed significantly. Subtype C expression in the caudate nucleus and putamen was elevated by stress (by 5 and 4%, respectively) but normalized during recovery. Quantification of 3H-RX821002 binding revealed receptor upregulation during stress and/or recovery. Our data therefore show: (i) that chronic psychosocial stress differentially regulates expression of ,2 -adrenoceptor subtypes A and C; (ii) that subtype A heteroreceptor expression is persistently upregulated whereas (iii), subtype C upregulation is only transient. The present findings coincide with post mortem studies in depressed patients revealing upregulation of ,2A -ARs. [source]


    Mirtazapine enhances frontocortical dopaminergic and corticolimbic adrenergic, but not serotonergic, transmission by blockade of ,2 -adrenergic and serotonin2C receptors: a comparison with citalopram

    EUROPEAN JOURNAL OF NEUROSCIENCE, Issue 3 2000
    M. J. Millan
    Abstract Mirtazapine displayed marked affinity for cloned, human ,2A -adrenergic (AR) receptors at which it blocked noradrenaline (NA)-induced stimulation of guanosine-5,-O-(3-[35S]thio)-triphosphate ([35S]-GTP,S) binding. Similarly, mirtazapine showed high affinity for cloned, human serotonin (5-HT)2C receptors at which it abolished 5-HT-induced phosphoinositide generation. Alpha2 -AR antagonist properties were revealed in vivo by blockade of UK-14,304-induced antinociception, while antagonist actions at 5-HT2C receptors were demonstrated by blockade of Ro 60 0175-induced penile erections and discriminative stimulus properties. Mirtazapine showed negligible affinity for 5-HT reuptake sites, in contrast to the selective 5-HT reuptake inhibitor, citalopram. In freely moving rats, in the dorsal hippocampus, frontal cortex (FCX), nucleus accumbens and striatum, citalopram increased dialysate levels of 5-HT, but not dopamine (DA) and NA. On the contrary, mirtazapine markedly elevated dialysate levels of NA and, in FCX, DA, whereas 5-HT was not affected. Citalopram inhibited the firing rate of serotonergic neurons in dorsal raphe nucleus, but not of dopaminergic neurons in the ventral tegmental area, nor adrenergic neurons in the locus coeruleus. Mirtazapine, in contrast, enhanced the firing rate of dopaminergic and adrenergic, but not serotonergic, neurons. Following 2 weeks administration, the facilitatory influence of mirtazapine upon dialysate levels of DA and NA versus 5-HT in FCX was maintained, and the influence of citalopram upon FCX levels of 5-HT versus DA and NA was also unchanged. Moreover, citalopram still inhibited, and mirtazapine still failed to influence, dorsal raphe serotonergic neurons. In conclusion, in contrast to citalopram, mirtazapine reinforces frontocortical dopaminergic and corticolimbic adrenergic, but not serotonergic, transmission. These actions reflect antagonist properties at ,2A -AR and 5-HT2C receptors. [source]


    Ultrastructural localization of salivary mucins MUC5B and MUC7 in human labial glands

    EUROPEAN JOURNAL OF ORAL SCIENCES, Issue 1 2010
    Monica Piras
    Piras M, Hand AR, Tore G, Ledda GP, Piludu M. Ultrastructural localization of salivary mucins MUC5B and MUC7 in human labial glands. Eur J Oral Sci 2010; 118: 14,18. © 2010 The Authors. Journal compilation © 2010 Eur J Oral Sci As a result of their presence throughout the mouth in the submucosa or between muscle fibers, minor salivary glands secrete directly and continuously into the oral cavity, providing mucosal surfaces with highly glycosylated proteins that are active in bacterial aggregation and in oral tissue lubrication. In this study, we investigated the ultrastructural localization of the MUC5B and MUC7 mucins in human labial glands by means of a postembedding immunogold technique. Thin sections of normal human labial glands, obtained during surgery, were incubated with polyclonal antibodies to human salivary mucins MUC5B and MUC7, and then with gold-labeled secondary antibodies. Specific MUC5B reactivity was found in the secretory granules of mucous cells of all glands examined, and was associated with the luminal membrane of duct cells. MUC7 labeling was observed in the granules of both mucous and seromucous secretory cells of the glandular parenchyma. Quantitative analyses demonstrated that seromucous granules have higher immunogold labeling densities for MUC7 than mucous granules. Our immunohistochemical data extend the results of previous light microscopic studies of MUC5B and MUC7 localizations, pointing out the significant contribution of human labial glands in the secretion process of these two mucins. [source]