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Possible Implications (possible + implication)
Selected AbstractsUpregulation of Serotonin Transporter by Alcohol in Human Dendritic Cells: Possible Implication in Neuroimmune DeregulationALCOHOLISM, Issue 10 2009Dakshayani Kadiyala Babu Background:, Alcohol is the most widely abused substance and its chronic consumption causes neurobehavioral disorders. It has been shown that alcohol affects the function of immune cells. Dendritic cells (DC) serve as the first line of defense against infections and are known to accumulate neurotransmitters such as 5-hydroxytryptamine (5-HT). The enzyme monoamine oxidase-A (MAO-A) degrades 5-HT that is associated with clinical depression and other neurological disorders. 5-HT is selectively transported into neurons through the serotonin transporter (SERT), which is a member of the sodium- and chloride-dependent neurotransmitter transporter (SLC6) family. SERT also serves as a receptor for psychostimulant recreational drugs. It has been demonstrated that several drugs of abuse such as amphetamine and cocaine inhibit the SERT expression; however, the role of alcohol is yet to be elucidated. We hypothesize that alcohol can modulate SERT and MAO-A expression in DC, leading to reciprocal downregulation of 5-HT in extracellular medium. Methods:, Dendritic cells were treated with different concentrations (0.05% to 0.2%v/v) of alcohol for 24,72 hours and processed for SERT and MAO-A expression using Q-PCR and Western blots analysis. In addition, SERT function in DC treated with alcohol both in the presence and absence of imipramine, a SERT inhibitor was measured using 4-[4-(dimethylamino)styryl]-1-methylpyridinium iodide uptake assay. 5-HT levels in culture supernatant and intracellular 5-hydroxy indole acetic acid (5-HIAA) and cyclic AMP were also quantitated using ELISA. Results:, Dendritic cells treated with 0.1% alcohol for 24 hours showed significant upregulation of SERT and MAO-A expression compared with untreated DC. We also observed that 0.1% alcohol enhanced the function of SERT and decreased extracellular 5-HT levels compared with untreated DC cultures, and this was associated with the elevation of intracellular 5-HIAA and cyclic AMP levels. Conclusions:, Our study suggests that alcohol upregulates SERT and MAO-A by elevating cyclic AMP, which may lead to decreased concentration of 5-HT in the extracellular medium. As 5-HT is a major neurotransmitter and an inflammatory mediator, its alcohol-mediated depletion may cause both neurological and immunological deregulation. [source] Long-Chain Polyamines (LCPAs) from Marine Sponge: Possible Implication in Spicule FormationCHEMBIOCHEM, Issue 14 2007Satoko Matsunaga Abstract Two distinct marine organisms, diatoms and sponges, deposit dissolved silicates to construct highly architectural and species-specific body supports. Several factors such as proteins, long-chain polyamines (LCPAs), or polypeptides modified with LCPAs are known to be involved in this process. The LCPAs contained in the silica walls of diatoms are thought to play pivotal roles in the silica deposition. In sponges, however, a protein called silicatein and several other proteins have been reported to be the factors involved in the silica deposition. However, no other factors involved in this process have been reported. We have identified the LCPAs from the marine sponge Axinyssa aculeata and present here some evidence that sponge-derived LCPAs can deposit silica and that the LCPA derivatives are associated with spicules. The results indicate a common chemistry between sponges and diatoms, the two major players in the biological circulation of silicon in the marine environment. A wide variety of organisms are known to utilize silica in their biological processes. Polyamines or other functional molecules might be involved, in combination with proteins, in their biosilicification process. [source] Singapore's Emerging Knowledge Economy: Role of Intellectual Property and its Possible Implications for Singaporean SocietyTHE JOURNAL OF WORLD INTELLECTUAL PROPERTY, Issue 3 2006Robin Ramcharan This article seeks to take an exploratory and critical look at the role of intellectual property (IP) in the development of Singapore. IP protection has become an important factor in the move to a knowledge-based economy (KBE), in which information is a prized asset. In order to preserve its traditional role as a regional trading entrepôt, its economy has evolved from an initial concentration on heavy industry-based manufacturing to manufacturing in knowledge-intensive products (electronics, chemicals and engineering), and the provision of financial and banking services. IP is now, arguably, a critical factor in the latest attempts by the Singaporean leadership to remain relevant to the regional and global economy. Faced with numerous competitors and cheaper labor markets, an impressive drive has been launched towards the enhancement of knowledge-intensive industries for which IP protection is vital. These include the creative industries strategy (copyright industries) and the provision of biomedical services (pharmaceutical, medical devices, biotechnology and healthcare services), the "fourth pillar" of Singapore's manufacturing sector, in addition to electronics, chemicals and engineering. Singapore seeks a competitive edge in this niche, for which IP protection seems vital. Patents are particularly relevant to the fourth pillar. This article will examine the following: (1) the place of IP historically in its economic development; (2) its role in various aspects of various strategies in its current economic development plans,the creative industries strategy, the intelligent island strategy and the fourth pillar strategy; and (3) critical IP issues for Singapore's economy. It does so with several key questions in mind. (1) Could the drive to an IP intensive knowledge economy generate social dislocations? (2) Which segments of Singaporean society stand to gain or lose in the move to an intensively knowledge-based economy? (3) Can the IP system contribute to softening the blow in any such dislocations? This article seeks to stimulate research into the social and economic impact of IP in Singapore's developmental process, an area thus far understudied. [source] The dark triad: Facilitating a short-term mating strategy in menEUROPEAN JOURNAL OF PERSONALITY, Issue 1 2009Peter K. Jonason Abstract This survey (N,=,224) found that characteristics collectively known as the Dark Triad (i.e. narcissism, psychopathy and Machiavellianism) were correlated with various dimensions of short-term mating but not long-term mating. The link between the Dark Triad and short-term mating was stronger for men than for women. The Dark Triad partially mediated the sex difference in short-term mating behaviour. Findings are consistent with a view that the Dark Triad facilitates an exploitative, short-term mating strategy in men. Possible implications, including that Dark Triad traits represent a bundle of individual differences that promote a reproductively adaptive strategy are discussed. Findings are discussed in the broad context of how an evolutionary approach to personality psychology can enhance our understanding of individual differences. Copyright © 2008 John Wiley & Sons, Ltd. [source] Self-esteem and suicide rates in 55 NationsEUROPEAN JOURNAL OF PERSONALITY, Issue 1 2009Armand Chatard Abstract Using recent data from the International Sexuality Description Project (ISDP), we examined whether national differences in self-esteem across 55 nations are reflected in suicide rates. Results indicate that suicide is especially common in nations with relatively low levels of self-esteem. This relation is consistent across sex lines, age of suicide and independent from several other relevant factors such as economic affluence, transition, individualism, subjective well-being, and neuroticism. These findings provide support for the predictive validity of self-esteem scores as assessed in the ISDP survey. They also contribute to a growing body of research documenting negative consequences associated with low self-esteem. Possible implications for suicide prevention strategies are discussed. Copyright © 2008 John Wiley & Sons, Ltd. [source] Quantum field theories coupled to supergravityFORTSCHRITTE DER PHYSIK/PROGRESS OF PHYSICS, Issue 3 2008J. Große Abstract This article is devoted to the investigation of the interplay of supersymmetric Yang,Mills theories (SYM) and supergravity (SUGRA). The topic is studied from two points of view: Firstly from the point of view of AdS/CFT correspondence, which realises the coupling of four dimensional superconformal ,, = 4 SYM theory and ten dimensional type IIB SUGRA in a holographic way. In order to arrive at theories that resemble quantum chromodynamics (QCD) more closely, fundamental fields are introduced using probe D7-branes and non-trivial background configuration are considered. In particular supergravity solutions that are only asymptotically anti-de Sitter and break supersymmetry are used. This allows the description of spontaneous chiral symmetry breaking. The meson spectrum is calculated and the existence of an associated Goldstone mode is demonstrated. Moreover it is shown that highly radially excited mesons are not degenerate. Additionally instanton configurations on the D7-branes are investigated, which lead to a holographic description of the dual field theory's Higgs branch. Finally a holographic description of heavy-light mesons is developed, which are mesons consisting of quarks with a large mass difference, such that a treatment of B mesons can be achieved The second approach is the technique of so-called space-time dependent couplings (also known as "local couplings"), where coupling constants are promoted to external sources. This allows to explore the conformal anomaly of quantum field theories coupled to a classical gravity background. The technique is extended to the superfield description of ,, = 1 supergravity, a complete basis for the anomaly is given and the consistency conditions that arise from a cohomological treatment are calculated. Possible implications for an extension of Zamolodchikov's c -theorem to four dimensional supersymmetric quantum field theories are discussed. [source] Contingent valuation in health care: does it matter how the ,good' is described?HEALTH ECONOMICS, Issue 5 2008Richard D. Smith Abstract A general population sample of 104 Australian respondents completed an interviewer-administered contingent valuation (CV) survey that asked them to value five scenarios representing the same core improvement in health status. These scenarios varied only in the degree of narrative used to describe the condition causing the health problem being valued and labeling of this health problem. Results indicate no significant difference in willingness to pay (WTP) between expressing symptoms as a brief or moderate narrative, but a significantly lower WTP value when expressed in an extensive narrative. WTP also differed significantly according to condition ,labels'. Possible implications for CV research are outlined. Copyright © 2007 John Wiley & Sons, Ltd. [source] Seasonal and inter-annual variability of the moisture sources for Alpine precipitation during 1995,2002INTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 7 2010Harald Sodemann Abstract This study presents a first quantitative climatology of the moisture sources for precipitation in the European Alps, covering a 7-year period from January 1995 to August 2002. Using a Lagrangian moisture source diagnostic and data from the ERA-40: European Centre for Medium-Range Weather Forecasts (ECMWF) reanalysis, the contribution of the following moisture sources to annual mean precipitation has been diagnosed: North Atlantic ocean 39.6%, Mediterranean 23.3%, North Sea and Baltic Sea 16.6%, and European land surface 20.8%. However, strong seasonal variability of the influence of various moisture sources is evident. Most notably, moisture transport to the Alps changes from an oceanic mode characterised by dominantly North Atlantic moisture sources during winter to a continental mode during summer with a marked contribution from Central European land areas. The method identifies inter-annual variability with respect to the location of the moisture sources in the North Atlantic, and the importance of precipitation recycling during summer. Despite the smoothed Alpine orography in the ERA-40 model, the Alps act as an effective barrier for meridional moisture transport, leading to distinct mean moisture source locations at their northern and southern slopes. The Northern Alps are predominantly influenced by the North Atlantic ocean and Central European land sources with a clear seasonality and limited monthly variability. In contrast, the Southern Alps receive a large fraction of precipitation from the Mediterranean with considerable month-to-month variability. Possible implications of these differences for precipitation extremes and stable isotopes in precipitation are discussed. Copyright © 2009 Royal Meteorological Society [source] Nurses' experiences of being present with a patient receiving a diagnosis of cancerJOURNAL OF ADVANCED NURSING, Issue 3 2000Una Dunniece DipN BSc(Hons) RN Nurses' experiences of being present with a patient receiving a diagnosis of cancer This paper reports the findings of a study which describes the experiences of nurses who were present with a patient when they received a diagnosis of cancer, cancer recurrence or prognosis of terminal cancer. Semi-structured interviews were conducted with six nurses who had experience of caring for patients with cancer in an acute surgical setting. Data were analysed using a phenomenological descriptive approach. Participants' descriptions revealed the following seven core themes: ,What if it was me?'; divergent feelings; being there; becoming closer; method of disclosure; time as an influence and learning by reflection. Possible implications for nursing practice and education are discussed and recommendations are made for future research. [source] Could repressive coping be a mediating factor in the symptom profile of individuals diagnosed with schizophrenia?JOURNAL OF PSYCHIATRIC & MENTAL HEALTH NURSING, Issue 5 2010B. SCHOLES rmn bn spq (mental health) msc pgctlhe Accessible summary ,,This paper considers the potential impact of identifying individual coping style on the concept of schizophrenia within the framework of the stress vulnerability model. There is discussion of the role of psychological theories in our understanding of schizophrenia and the experience of those who live with this condition. ,,The concept of individual coping style, with particular attention to repressive coping style, is considered and the research on the impact of coping style on the person's mental and physical well-being is discussed. Whether this way of thinking about and understanding repression is helpful in how we understand schizophrenia is then considered. ,,Possible implications of identifying repression in people with schizophrenia by using the idea of coping style as a measure of this concept are considered, gaining and understanding of what role this identification may have on our understanding of how people experience this condition and express this experience to those who work with them. ,,The potential for study in this area may allow a greater understanding of the way in which our protective psychological functions interact with experience of the distressing and challenging symptoms, often associated with schizophrenia, and influence future understanding of the process and progress of this condition. Abstract Despite a relatively high prevalence, and the enduring patronage of the disorder by psychiatry and the pharmaceutical industry, innovative conceptualization of schizophrenia in a client-empowering and quality of life-enhancing way appears to represent a vacuum within the clinical agenda, certainly taking second place to ,patient management'. However, against this bland background of medicalization of what is clearly a poorly understood and complex multifactorial syndrome, innovative treatment approaches aimed at symptom control, in particular, the stress vulnerability model (SVM), have been developed. However, the SVM is an incomplete model of patient experience and says little of aetiological note. One area of psychological function that may give further insight into the symptom experience associated with schizophrenia within the context of stress vulnerability concerns the mechanisms of repression. Ironically, the notion of repression will for many represent the epitome of non-evidence-based psychiatric theory and related psychodynamic therapy practice. However, more contemporary work within the psychological literature has aimed to make the concept both measurable and observable. No longer occluded by the context of psychoanalysis, cognitive science accounts of repression may be of value in facilitating understanding of the variability and predictability of symptoms of schizophrenia and may provide a dimension of therapeutic engagement allied to the SVM. [source] Coherent synchrotron emission from cosmic ray air showersMONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 4 2006Qinghuan Luo ABSTRACT Coherent synchrotron emission by particles moving along semi-infinite tracks is discussed, with a specific application to radio emission from air showers induced by high-energy cosmic rays. It is shown that in general, radiation from a particle moving along a semi-infinite orbit consists of usual synchrotron emission and modified impulsive bremsstrahlung. The latter component is due to the instantaneous onset of the curved trajectory of the emitting particle at its creation. Inclusion of the bremsstrahlung leads to broadening of the radiation pattern and a slower decay of the spectrum at the cut-off frequency than the conventional synchrotron emission. Possible implications of these features for air shower radio emission are discussed. [source] Projections of the Ethnic Minority Populations of the United Kingdom 2006,2056POPULATION AND DEVELOPMENT REVIEW, Issue 3 2010David Coleman The ethnic minority populations in the UK are growing substantially through immigration, a youthful age structure, and in some cases relatively high fertility. Their diverse demographic and socioeconomic characteristics have attracted considerable academic and policy attention, especially insofar as those distinctive characteristics have persisted in the generations born in the UK. No official projections of the UK ethnic populations have been published since 1979. This article provides projections to 2056 and beyond of 12 ethnic groups. Given overall net immigration and vital rates as assumed in the office for National Statistics 2008-based Principal Projection, and the ethnic characteristics estimated here, the ethnic minority populations (including the Other White) would increase from 13 percent of the UK population in 2006 to 28 percent by 2031 and 44 percent by 2056, and to about half the 0,4 age group in 2056. Alternative projections assume various lower levels of immigration. Possible implications of projected changes are discussed. [source] Src kinase activation: A switched electrostatic networkPROTEIN SCIENCE, Issue 5 2006Elif Ozkirimli Abstract Src tyrosine kinases are essential in numerous cell signaling pathways, and improper functioning of these enzymes has been implicated in many diseases. The activity of Src kinases is regulated by conformational activation, which involves several structural changes within the catalytic domain (CD): the orientation of two lobes of CD; rearrangement of the activation loop (A-loop); and movement of an ,-helix (,C), which is located at the interface between the two lobes, into or away from the catalytic cleft. Conformational activation was investigated using biased molecular dynamics to explore the transition pathway between the active and the down-regulated conformation of CD for the Src-kinase family member Lyn kinase, and to gain insight into the interdependence of these changes. Lobe opening is observed to be a facile motion, whereas movement of the A-loop motion is more complex requiring secondary structure changes as well as communication with ,C. A key result is that the conformational transition involves a switch in an electrostatic network of six polar residues between the active and the down-regulated conformations. The exchange between interactions links the three main motions of the CD. Kinetic experiments that would demonstrate the contribution of the switched electrostatic network to the enzyme mechanism are proposed. Possible implications for regulation conferred by interdomain interactions are also discussed. [source] Legal issues in school health services and school psychology: Guidelines for the administration of medicationPSYCHOLOGY IN THE SCHOOLS, Issue 9 2009Anna Mazur-Mosiewicz The use of psychoactive medications to augment behavioral and psychosocial interventions in schools has significantly increased within the last few decades. Yet, advising, administrating, and supervising the dispensation of medication (including psychostimulants and psychoactive substances) tend to be some of the most risky tasks of school administrators and personnel. Medication administration is not only an increasing source of civil and administrative liability for school districts, but may lead to legal questions for school counselors, psychologists, and social workers. In response to growing concerns, this article provides guidelines necessary for safe medication administration and monitoring in the school setting. Federal, state, and district guidelines are reviewed. Possible implications for school and district policy makers, principals, teachers, school nurses, school psychologists, social workers, counselors, and parents are outlined. © 2009 Wiley Periodicals, Inc. [source] Schedule-induced electrodermal responding in childrenPSYCHOPHYSIOLOGY, Issue 6 2006Robert D. Latzman Abstract The current studies were designed to determine whether different intermittent schedules of reinforcement would have a differential effect on the skin conductance responses (SCRs) of children in the 8,12-year-old age range. Results of two experiments indicated that the amplitude of children's SCRs immediately following the occurrence of reinforcement were a function of the schedule of reinforcement, with larger SCRs associated with longer inter-reinforcement intervals. The findings are consistent with the research literature suggesting that long inter-reinforcement intervals can be evocative of aversively motivated emotions, as well as with research on the effects of interstimulus intervals on SCRs. Possible implications for these findings are discussed. [source] Hypoxia-inducible factor regulation of ANK expression in nucleus pulposus cells: Possible implications in controlling dystrophic mineralization in the intervertebral discARTHRITIS & RHEUMATISM, Issue 9 2010Renata Skubutyte Objective Since nucleus pulposus cells reside under conditions of hypoxia, we determined if the expression of ANK, a pyrophosphate transporter, is regulated by the hypoxia-inducible factor (HIF) proteins. Methods Quantitative reverse transcription,polymerase chain reaction and Western blot analyses were used to measure ANK expression in nucleus pulposus cells from rats and humans. Transfections were performed to determine the effect of HIF-1/2 on ANK promoter activity. Results ANK was expressed in embryonic and mature rat discs. Oxygen-dependent changes in ANK expression in nucleus pulposus cells were minimal. However, silencing of HIF-1, and HIF-2, resulted in increased ANK expression and up-regulation of promoter activity. HIF-mediated suppression of ANK was validated by measuring promoter activity in HIF-1,,null embryonic fibroblasts. Under conditions of hypoxia, there was induction of promoter activity in the null cells as compared with the wild-type cells. Overexpression of HIF-1, and HIF-2, in nucleus pulposus cells resulted in a significant suppression of ANK promoter activity. Since the ANK promoter contains 2 hypoxia-responsive elements (HREs), we performed site-directed mutagenesis and measured promoter activity. We found that HIF-1 can bind to either of the HREs and can suppress promoter activity; in contrast, HIF-2 was required to bind to both HREs in order to suppress activity. Finally, analysis of human nucleus pulposus tissue showed that while ANK was expressed in normal tissue, there was increased expression of ANK along with alkaline phosphatase in the degenerated state. Conclusion Both HIF-1 and HIF-2 serve as negative regulators of ANK expression in the disc. We propose that baseline expression of ANK in the disc serves to prevent mineral formation under physiologic conditions. [source] Enthalpy relaxation of bovine serum albumin and implications for its storage in the glassy state,BIOPOLYMERS, Issue 2 2005Asgar Farahnaky Abstract Two endothermic peaks could be observed for five commercial samples of bovine serum albumin (BSA). The smaller peak observed by differential scanning calorimetry (DSC) corresponded to enthalpy relaxation. This peak was followed on storage of BSA, in its glassy state, after it had been heated above its denaturation temperature. Enthalpy and peak temperature increased with duration of storage. On storage for one week at 60°C, a sample at 8.3% moisture showed a peak at 100°C with an energy value of approximately 2 J per g protein. BSA samples were heated within the DSC sufficiently to eliminate the lower enthalpy peak but without altering the denaturation enthotherm. The amount of physical aging shown by these BSA samples was similar to that of the heat-denatured samples. It was concluded that the heating endotherms of dry BSA reflect both the storage and thermal history of the sample. Possible implications of the enthalpy relaxation of BSA on the behavior of this important protein are considered. © 2005 Wiley Periodicals, Inc. Biopolymers 78: 69,77, 2005 [source] Comparative Metabolism of ,- and ,- Peptides in the Insect Heliothis virescens and in Plant Cells of Black Mexican Sweet MaizeCHEMISTRY & BIODIVERSITY, Issue 9 2004Rob Lind The tripeptide H-Val-Ala-Leu-OH and the N -Ac-tetrapeptide amide Ac-Thr-Lys-Trp-Phe-NH2, and their , -peptidic counterparts H- ,3hVal- ,3hAla- ,3hLeu-OH and Ac- ,3hThr-(S),2hLys- ,3hTrp- ,3hPhe-NH2, respectively, have been injected into Heliothis virescens larvae and added to cell cultures of black mexican sweet maize. The body liquids of the larvae and the supernatant of the plant cell cultures were sampled 0, 2, 3, 6, 17, and/or 24,h after application and analyzed by LC/MS. While the two , -peptides were degraded rapidly in these environments, the concentration of the , -peptides was found to decrease very slowly. Thus, ca. 60% of the original amount of the , -tetrapeptide was detected in the liquids of the insect after 24,h. The plant cells did not seem to make use of the , -peptides at all, whereas, the , -tripeptide completely disappeared from the supernatant after 3,h. Thus, we have demonstrated, for the first time, the high stability of , -peptides against degradation and metabolism in an insect and a plant. Especially remarkable is the persistence of the , -tetrapeptide with its functionalised and, thus, ,metabolisable' side chains of Thr, Lys, Trp, and Phe in the insect larvae, which are known to have a high level of activity of oxidizing enzymes. The results described here match those of ADME investigations with radioactively labeled , -peptides in rats, where essentially complete stability has been observed, while environmental microorganisms have been found to biodegrade , -peptides, albeit slowly. Possible implications of these findings for biomedical and pest-control applications are proposed. [source] Using Rock-Eval 6 pyrolysis for tracking fossil organic carbon in modern environments: implications for the roles of erosion and weatheringEARTH SURFACE PROCESSES AND LANDFORMS, Issue 2 2006Yoann Copard Abstract This work relates to the debate on the fossil organic carbon (FOC) input in modern environments and its possible implication for the carbon cycle, and suggests the use of Rock-Eval 6 pyrolysis as a relevant tool for tracking FOC in such environments. Considering that such a delivery is mainly due to supergene processes affecting the continental surface, we studied organic matter in different reservoirs such as bedrocks, alterites, soils and rivers in two experimental catchments at Draix (Alpes de Haute Provence, France). Samples were subjected to geochemical (Rock-Eval 6 pyrolysis) investigations and artificial bacterial degradations. After comparing the geochemical fingerprint of samples, geochemical markers of FOC were defined and tracked in the different reservoirs. Our results confirm the contribution of FOC in modern soils and rivers and display the various influences of weathering and erosional processes on the fate of FOC during its exchange between these pools. In addition, the contrasting behaviour of these markers upon the supergene processes has also highlighted the refractory or labile characters of the fossil organic matter (FOM). Bedrock to river fluxes, controlled by gully erosion, are characterized by a qualitative and quantitative preservation of FOM. Bedrock to alterite fluxes, governed by chemical weathering, are characterized by FOC mineralization without qualitative changes in deeper alterites. Alterite to soils fluxes, controlled by (bio)chemical weathering, are characterized by strong FOC mineralization and qualitative changes of FOM. Thus weathering and erosional processes induce different FOM evolution and affect the fate of FOC towards the global carbon cycle. In this study, gully erosion would involve maintenance of an ancient sink for the global carbon cycle, while (bio)chemical processes provide a source of CO2. Finally, this study suggests that Rock-Eval 6 pyrolysis can be considered as a relevant tool for tracking FOC in modern environments. Copyright © 2006 John Wiley & Sons, Ltd. [source] Serotonin mediates oestrogen stimulation of cell proliferation in the adult dentate gyrusEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 9 2001Mounira Banasr Abstract Characterizing the mechanisms by which endogenous factors stimulate neurogenesis is of special interest in view of the possible implication of newly generated cells in hippocampal functions or disorders. The aim of this study was to determine whether serotonin (5-HT) and oestradiol (E2) act through a common pathway to increase cell proliferation in the adult dentate gyrus (DG). We also investigated the effects of long-lasting changes in oestrogen levels on cell proliferation. Combining ovariectomy with inhibition of 5-HT synthesis using p -chlorophenylalanine (PCPA) treatment produced approximately the same decreases in the number of bromodeoxyuridine (BrdU) and PSA-NCAM immunolabelled cells in the subgranular layer as ovariectomy alone. Administration of 5-hydroxytryptophan (5-HTP) restored cell proliferation primarily decreased by ovariectomy, whereas oestradiol was unable to reverse this change in ovariectomized rats treated with PCPA. These findings demonstrate that 5-HT mediates oestrogen stimulation of cell proliferation in adult dentate gyrus. However, increase in ovarian hormones during pregnancy has no effect on dentate cell proliferation. This finding suggests that concomitant changes in other factors, such as glucocorticoids, may counterbalance the positive regulation of cell proliferation by 5-HT and oestradiol. Finally, oestrogen may regulate structural plasticity by stimulating PSA-NCAM expression independently of neurogenesis, as shown for instance by the increases in the number of PSA-NCAM labelled cells in pregnants. As 5-HT and oestrogen are involved in mood disorders, our data suggest that the positive regulation of cell proliferation and neuroplasticity by these two factors may contribute to restore hippocampal connectivity in depressive patients. [source] Enhanced dopamine function in DISC1-L100P mutant mice: implications for schizophreniaGENES, BRAIN AND BEHAVIOR, Issue 7 2010T. V. Lipina Significant advances have been made in understanding the role of disrupted-in-schizophrenia-1 (DISC1) in the brain and accumulating findings suggest the possible implication of DISC1 in the regulation of dopamine (DA) function. A mutation in the second exon of DISC1 at L100P leads to the development of schizophrenia-related behavior in mutant mice (DISC1-L100P). We investigated here the role of DA in the expression of schizophrenia-related endophenotypes in the DISC1-L100P genetic mouse model. The mutated DISC1 resulted in facilitation of the psychostimulant effect of amphetamine in DISC1-L100P mutant mice assessed in the open field and prepulse inhibition (PPI) tests. Biochemical studies detected a 2.1-fold increase in the proportion of striatal Dreceptors without significant changes in DA release in vivo in the striatum of DISC1-L100P mutants in response to the low dose of amphetamine. The D2 receptor antagonist haloperidol reversed the hyperactivity, PPI and latent inhibition (LI) deficits and blocked the psychostimulant effect of amphetamine in DISC1-L100P mutants. Taken together, our findings show the role of DISC1 in D2 -related pathophysiological mechanism of schizophrenia, linking DISC1 with well-established DA hypothesis of schizophrenia. [source] Single nucleotide polymorphisms in succinate dehydrogenase subunits and citrate synthase genes: association results for impaired spermatogenesisINTERNATIONAL JOURNAL OF ANDROLOGY, Issue 3 2007Sandra Bonache Abstract Evaluation of the possible implication of the SDHA, SDHB, SDHC, SDHD and CS genes in non-obstructive male infertility was performed on the basis that sperm concentration in the ejaculate has been previously correlated with nuclear-encoded mitochondrial enzyme activities (the four subunits of succinate dehydrogenase/complex II of the respiratory chain and citrate synthase). We performed an exhaustive analysis of the five genes for the presence of sequence variants that could be associated with impairment of sperm production. blastn searches in the genomic sequence NCBI database evidenced the presence of highly homologous sequences elsewhere on the genome that can interfere with polymerase chain reaction experiments. Therefore, a careful design of the analytical strategy to search for sequence variants was performed. In this report, we provide primer sequences that allowed selective amplification of coding and immediate flanking regions of the five genes. Fifty-five sequence variations in the five genes were identified in infertile and normozoospermic fertile individuals as controls and only one of them (SDHA c.456+32G>A) showed significant genotype association with impairment of sperm production. Moreover, new single nucleotide polymorphisms identified should be useful in future association studies for other human diseases related to nuclear-encoded genes, leading to mitochondrial respiratory chain activity impairment revealing the physiological role of these genes. [source] The T-box transcription factor Tbx2: Its role in development and possible implication in cancerIUBMB LIFE, Issue 2 2010Amaal Abrahams Abstract Tbx2 is a member of the T-box family of transcription factors that are crucial in embryonic development. Recent studies suggest that T-box factors may also play a role in controlling cell cycle progression and in the genesis of cancer. Tbx2 has been implicated in several developmental processes such as coordinating cell fate, patterning and morphogenesis of a wide range of tissues and organs including limbs, kidneys, lungs, mammary glands, heart, and craniofacial structures. Importantly, Tbx2 is overexpressed in several cancers including melanoma, small cell lung carcinoma, breast, pancreatic, liver, and bladder cancers and can suppress senescence, a cellular process, which serves as a barrier to cancer development. This review presents a state of the art overview of the role and regulation of Tbx2 in early embryonic development and in cancer. © 2009 IUBMB IUBMB Life, 62(2): 92,102, 2010 [source] Paraoxonase 1 activities and polymorphisms in autism spectrum disordersJOURNAL OF CELLULAR AND MOLECULAR MEDICINE, Issue 3 2010Sergiu P. Pa Abstract Autism spectrum disorders (ASD) comprise a complex and heterogeneous group of conditions of unknown aetiology, characterized by significant disturbances in social, communicative and behavioural functioning. Recent studies suggested a possible implication of the high-density lipoprotein associated esterase/lactonase paraoxonase 1 (PON1) in ASD. In the present study, we aimed at investigating the PON1 status in a group of 50 children with ASD as compared to healthy age and sex matched control participants. We evaluated PON1 bioavailability (i.e. arylesterase activity) and catalytic activity (i.e. paraoxonase activity) in plasma using spectrophotometric methods and the two common polymorphisms in the PON1 coding region (Q192R, L55M) by employing Light Cycler real-time PCR. We found that both PON1 arylesterase and PON1 paraoxonase activities were decreased in autistic patients (respectively, P < 0.001, P < 0.05), but no association with less active variants of the PON1 gene was found. The PON1 phenotype, inferred from the two-dimensional enzyme analysis, had a similar distribution in the ASD group and the control group. In conclusion, both the bioavailability and the catalytic activity of PON1 are impaired in ASD, despite no association with the Q192R and L55M polymorphisms in the PON1 gene and a normal distribution of the PON1 phenotype. [source] CD 95 mediated apoptosis in embryogenesis: implication in tooth developmentORTHODONTICS & CRANIOFACIAL RESEARCH, Issue 3 2006E Matalová Structured abstract Authors,,, Matalová E, ,etková J, Blackburn J, Mí,ek I, Sharpe PT Introduction,,, Understanding of apoptotic mechanisms involved in tissue shaping is of particular interest because of possible targeted modulation of the development of organ structures such as teeth. Research of CD 95 mediated apoptosis has been focused particularly on cell death in the immune system and related disorders. However, CD 95 mediated apoptosis is also involved in embryogenesis of many organs as the kidney, the lung, the intestine and tissue networks such as the nervous system. Design,,, Narrative review. Results,,, This review briefly summarizes the current knowledge of CD 95 mediated apoptosis in embryogenesis with possible implication in tooth development. CD 95 receptor and CD 95 ligand are found at early stages of tooth development. The data suggest some positive correlations with dental apoptosis distribution, particularly in the primary enamel knot where apoptosis occurs during elimination of this structure. CD 95 deficient (lpr) adult mouse tooth phenotype, however, did not show any alterations in final tooth pattern and morphology. Conclusion,,, To date studies of apoptotic machinery during tooth development show spatial localization of many of the components together with precise and localized timing of cell death. There is still much to be learned about the regulation and importance of apoptosis in tooth development. Nevertheless, the involvement of apoptotic regulatory mechanisms interplaying with other molecules participates to the cellular cross-talk in developing tissues, which opens possible targeted modulations as suggested, e.g. for future molecular dentistry. [source] Impact of the heroin ,drought' on patterns of drug use and drug-related harmsDRUG AND ALCOHOL REVIEW, Issue 2 2004Dr MARIE C. LONGO Senior Research Officer Abstract Since late 2000, anecdotal reports from drug users and health professionals have suggested that there was a reduction in the supply of heroin in Adelaide in the first half of 2001, referred to as a heroin ,drought'. The aim of this paper was to critically review evidence for this, using data obtained from 100 injecting drug users surveyed for the 2001 Illicit Drug Reporting System (IDRS). This project is carried out annually in all Australian jurisdictions, and collects up-to-date information on the markets for heroin, methamphetamine, cocaine and cannabis. This paper also investigates the possible implications of this ,drought' on patterns of drug use and drug-related harms. The 2001 IDRS found consistent reports by users of an increase in the price of heroin, together with decreases in purity and availability. These factors resulted in a decrease in the frequency of self-reported heroin use among those surveyed in 2001, and a concomitant increase in the use of other drugs, in particular methamphetamine and morphine. The heroin ,drought' appears to have had a substantial impact on several indices of drug-related harm. There was a marked decrease in the number of opioid-related fatalities, and hospital data also showed reductions in heroin-related presentations. Treatment service data showed an increase in the number of admissions related to amphetamines. There is a need for health promotion and education on the adverse effects of methamphetamine use, and the development of improved treatment protocols for methamphetamine abuse and dependence. [source] Mortgage credit conditions in the UKECONOMIC OUTLOOK, Issue 3 2002John Muellbauer It is widely perceived that credit conditions for UK consumers, particularly in the mortgage market, have been radically liberalized since the 1970s. The implications for the housing market and consumer spending have been important. This article by John Muellbauer draws on a 1997 paper by the author which examined data from the Survey of Mortgage Lenders to learn, from information about loan-to-value ratios of first-time buyers, classified by region, about changes in mortgage credit conditions. By controlling for economic and demographic influences on credit conditions, a single time-varying index of mortgage credit conditions was extracted from these SML data. This index rises in the 1980s, peaking towards the end of the decade. It retraces part of its rise in the early 1990s before rising again by 1995 to a level not far below the previous peak. The article considers whether more recent data suggest a further liberalisation of mortgage credit conditions. It draws on joint research with others to discuss possible implications for consumer spending, house prices, the volume of property transactions and mortgage defaults. [source] Intersections: The Simultaneity of Race, Gender and Class in Organization StudiesGENDER, WORK & ORGANISATION, Issue 3 2010Evangelina Holvino This article argues for a reconceptualization of the intersections of race, gender and class as simultaneous processes of identity, institutional and social practice in order to redress the lack of attention to these intersections in feminist organization studies. Grounding my argument on a brief critique of white liberal feminism from the perspective of women of colour, I examine other feminist frameworks beyond the dominant liberal paradigm and identify their possible contributions to the study of intersections in organization theory and practice. Specifically, I propose theoretical and methodological interventions for researching and practicing more forcefully and intentionally the simultaneity of race, gender and class in organizations, including researching and publicizing the hidden stories at the intersections of race, ethnicity, gender, class, nation and sexuality; identifying, untangling and changing the differential impact of everyday practices in organizations and identifying and linking internal organizational processes with external societal processes. I conclude with some reflections on the possible implications of these proposals for each of us, scholars and practitioners of gender and organization. [source] ROCK-SURFACE TEMPERATURES OF BASALT IN THE DRAKENSBERG ALPINE ENVIRONMENT, LESOTHOGEOGRAFISKA ANNALER SERIES A: PHYSICAL GEOGRAPHY, Issue 3 2007STEFAN GRAB ABSTRACT. Rock temperature data are presented for a variety of topographic localities at a high Drakensberg site. The objective is to investigate the spatiotemporal variations of surface rock temperatures in high Drakensberg basalt. The temperature results are then used to discuss possible implications for thermal stress fatigue and frost-induced weathering. TinytalkÔ data loggers and probes were used for rock-surface temperature recording. Long-term measurements were recorded over 12 months from May 2002 to April 2003, at a 1-hour logging interval and rock depth of 1 cm for a highaltitude (3300 m a.s.l.) interfluve and fracture site. Whilst the north-facing rock surface experiences negligible hours below ,3°C, the south-facing rock surface and interfluve sites are subjected to considerable periods below ,3°C, which falls within the ,frost cracking window'. It is concluded that the substantial contrasts of recorded rock thermal parameters over small spatial scales between various topographic settings, highlight that site-specific measurements across the broader scale are required for an adequate evaluation of regional weathering and its associated landform development. [source] An Island of Green in the Sunburnt Country: The Rainforest of the Humid Tropics of Northeastern Australia and Their Response to Quaternary Environmental ChangeGEOGRAPHY COMPASS (ELECTRONIC), Issue 6 2008Patrick T. Moss The Humid Tropics of northeastern Australia is a region of exceptional diversity and productivity that reflects many of the characteristics of similar tropical biomes. In the Australian context, it is a unique environment being a virtual ,island of green' surrounded by the more typical sclerophyll (i.e. dry and fire prone) landscapes of Australia. This article will examine the modern ecological characteristics of the region, as well as providing historical context by discussing the response of the humid tropics communities to Quaternary environmental upheavals and the possible implications that these alterations have for understanding ecosystem response to future environmental change. [source] | ||||||||||||||||||||||||||||||||||