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Evidence for Transgenerational Transmission of Epigenetic Tumor Susceptibility in Drosophila  [PDF]
Yalan Xing,Song Shi,Long Le,Crystal A Lee,Louise Silver-Morse,Willis X Li
PLOS Genetics , 2007, DOI: 10.1371/journal.pgen.0030151
Abstract: Transgenerational epigenetic inheritance results from incomplete erasure of parental epigenetic marks during epigenetic reprogramming at fertilization. The significance of this phenomenon, and the mechanism by which it occurs, remains obscure. Here, we show that genetic mutations in Drosophila may cause epigenetic alterations that, when inherited, influence tumor susceptibility of the offspring. We found that many of the mutations that affected tumorigenesis induced by a hyperactive JAK kinase, HopTum-l, also modified the tumor phenotype epigenetically, such that the modification persisted even in the offspring that did not inherit the modifier mutation. We analyzed mutations of the transcription repressor Krüppel (Kr), which is one of the hopTum-l enhancers known to affect ftz transcription. We demonstrate that the Kr mutation causes increased DNA methylation in the ftz promoter region, and that the aberrant ftz transcription and promoter methylation are both transgenerationally heritable if HopTum-l is present in the oocyte. These results suggest that genetic mutations may alter epigenetic markings in the form of DNA methylation, which are normally erased early in the next generation, and that JAK overactivation disrupts epigenetic reprogramming and allows inheritance of epimutations that influence tumorigenesis in future generations.
Transgenerational Transmission of the Glossina pallidipes Hytrosavirus Depends on the Presence of a Functional Symbiome  [PDF]
Drion G. Boucias, Henry M. Kariithi, Kostas Bourtzis, Daniela I. Schneider, Karen Kelley, Wolfgang J. Miller, Andrew G. Parker, Adly M. M. Abd-Alla
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0061150
Abstract: The vertically transmitted endosymbionts (Sodalis glossinidius and Wigglesworthia glossinidia) of the tsetse fly (Diptera: Glossinidae) are known to supplement dietary deficiencies and modulate the reproductive fitness and the defense system of the fly. Some tsetse fly species are also infected with the bacterium, Wolbachia and with the Glossina hytrosavirus (GpSGHV). Laboratory-bred G. pallidipes exhibit chronic asymptomatic and acute symptomatic GpSGHV infection, with the former being the most common in these colonies. However, under as yet undefined conditions, the asymptomatic state can convert to the symptomatic state, leading to detectable salivary gland hypertrophy (SGH+) syndrome. In this study, we investigated the interplay between the bacterial symbiome and GpSGHV during development of G. pallidipes by knocking down the symbionts with antibiotic. Intrahaemocoelic injection of GpSGHV led to high virus titre (109 virus copies), but was not accompanied by either the onset of detectable SGH+, or release of detectable virus particles into the blood meals during feeding events. When the F1 generations of GpSGHV-challenged mothers were dissected within 24 h post-eclosion, SGH+ was observed to increase from 4.5% in the first larviposition cycle to >95% in the fourth cycle. Despite being sterile, these F1 SGH+ progeny mated readily. Removal of the tsetse symbiome, however, suppressed transgenerational transfer of the virus via milk secretions and blocked the ability of GpSGHV to infect salivary glands of the F1 progeny. Whereas GpSGHV infects and replicates in salivary glands of developing pupa, the virus is unable to induce SGH+ within fully differentiated adult salivary glands. The F1 SGH+ adults are responsible for the GpSGHV-induced colony collapse in tsetse factories. Our data suggest that GpSGHV has co-evolved with the tsetse symbiome and that the symbionts play key roles in the virus transmission from mother to progeny.
How addicts think about addiction and community problems?
A. Meysamie,B. Faramarzi,K. Holakouie Naieni
Tehran University Medical Journal , 2006,
Abstract: Background: addiction and drug abuse have many risk factors in community and individual attitude; also causes much diversity in community perception and attitude toward addiction. Methods: in this study we assessed attitude toward an addict in 42 addict men and asked about problems in their community and recreational behaviors. They were residents of a rural area in Babol city. In the control group we assessed the same parameters in 268 non addicts in the same area. All of the addicts have been using opium more than many times a week at least for recent 6 months. Data collected via a semi structured questionnaire through conversation. Results: There was a significant difference between addicts’ attitude toward toward addiction compare to non-addicts’. Both addicts and non-addicts indicated that the first three community problems in their area were unemployment, lack of recreational facilities and addiction, in respective order. Answering questions about recreational activities, both groups indicated that there were no recreational facilities in the community. Conclusion: In planning a preventive approach, there is a major role for attitude toward addiction in any community. The conflict seen in this study between addicts’ attitudes toward an addicted person and addiction as a community problem has it’s interesting feature. Recreation and physical and cultural facilities need to pay more attention as indicated by our study participants. This seems to have an important impact in prevention of many community problems as well as addiction.
Transgenerational transmission of trauma and resilience: a qualitative study with Brazilian offspring of Holocaust survivors
Luciana Braga, Marcelo Mello, José Fiks
BMC Psychiatry , 2012, DOI: 10.1186/1471-244x-12-134
Abstract: This qualitative study aims to detect how the second generation perceives transgenerational transmission of their parents’ experiences in the Holocaust. In-depth individual interviews were conducted with fifteen offspring of Holocaust survivors and sought to analyze experiences, meanings and subjective processes of the participants. A Grounded Theory approach was employed, and constant comparative method was used for analysis of textual data.The development of conceptual categories led to the emergence of distinct patterns of communication from parents to their descendants. The qualitative methodology also allowed systematization of the different ways in which offspring can deal with parental trauma, which determine the development of specific mechanisms of traumatic experience or resilience in the second generation.The conceptual categories constructed by the Grounded Theory approach were used to present a possible model of the transgenerational transmission of trauma, showing that not only traumatic experiences, but also resilience patterns can be transmitted to and developed by the second generation. As in all qualitative studies, these conclusions cannot be generalized, but the findings can be tested in other contexts.More than 50?years after the liberation of Nazi concentration camps, researchers and clinicians are still devoted to studying the long-lasting consequences of the traumatic experiences endured by Holocaust survivors and their descendants. This is probably the most comprehensively researched case of transgenerational transmission of trauma [1]. Despite this, there are no published studies conducted with Brazilian offspring of Holocaust Survivors (OHS).This phenomenon has importance beyond the study of OHS. Many studies suggest that genocides in Rwanda, Nigeria, Cambodia, Armenia, and former Yugoslavia brought about distinct psychopathological symptoms in offspring of survivors [2]. Depression, posttraumatic stress disorder (PTSD), attention deficits
The Drug addiction changed in one of the the most serious problems in Russian Armed Power. For soldierly group drug addiction became one of leading factor of the risk for health of the personal composition and weakenings to combat readiness of a parts and join
Emeliyanov O. A.
Sociosfera , 2011,
Abstract: The Drug addiction changed in one of the the most serious problems in Russian Armed Power. For soldierly group drug addiction became one of leading factor of the risk for health of the personal composition and weakenings to combat readiness of a parts and join.
The Role of Cannabinoid Transmission in Emotional Memory Formation: Implications for Addiction and Schizophrenia  [PDF]
Michael Loureiro,Jordan Zunder,Steven R. Laviolette
Frontiers in Psychiatry , 2014, DOI: 10.3389/fpsyt.2014.00073
Abstract: Emerging evidence from both basic and clinical research demonstrates an important role for endocannabinoid (ECB) signaling in the processing of emotionally salient information, learning and memory. Cannabinoid transmission within neural circuits involved in emotional processing has been shown to modulate the acquisition, recall and extinction of emotionally salient memories and importantly, can strongly modulate the emotional salience of incoming sensory information. Two neural regions in particular, the medial prefrontal cortex (PFC) and the basolateral nucleus of the amygdala (BLA), play important roles in emotional regulation and contain high levels of cannabinoid receptors. Furthermore, both regions show profound abnormalities in neuropsychiatric disorders such as addiction and schizophrenia. Considerable evidence has demonstrated that cannabinoid transmission functionally interacts with dopamine (DA), a neurotransmitter system that is of exceptional importance for both addictive behaviours and the neuropsychopathology of disorders like schizophrenia. Research in our laboratory has focused on how cannabinoid transmission both within and extrinsic to the mesolimbic DA system, including the BLA?mPFC circuitry, can modulate both rewarding and aversive emotional information. In this review, we will summarize clinical and basic neuroscience research demonstrating the importance of cannabinoid signaling within this neural circuitry. In particular, evidence will be reviewed emphasizing the importance of cannabinoid signaling within the BLA?mPFC circuitry in the context of emotional salience processing, memory formation and memory-related plasticity. We propose that aberrant states of hyper or hypoactive ECB signaling within the amygdala-prefrontal cortical circuit may lead to dysregulation of mesocorticolimbic DA transmission controlling the processing of emotionally salient information. These disturbances may in turn lead to emotional processing, learning and memory a
Free transmission problems  [PDF]
Marcelo Amaral,Eduardo V. Teixeira
Mathematics , 2015, DOI: 10.1007/s00220-015-2290-3
Abstract: We study transmission problems with free interfaces from one random medium to another. Solutions are required to solve distinct partial differential equations, $\mbox{L}_{+}$ and $\mbox{L}_{-}$, within their positive and negative sets respectively. A corresponding flux balance from one phase to another is also imposed. We establish existence and $L^{\infty}$ bounds of solutions. We also prove that variational solutions are non-degenerate and develop the regularity theory for solutions of such free boundary problems.
Boundary stabilization of transmission problems  [PDF]
Fernando Cardoso,Georgi Vodev
Mathematics , 2009, DOI: 10.1063/1.3277163
Abstract: We study the transmission problem in bounded domains with dissipative boundary conditions. Under some natural assumptions, we prove uniform bounds of the corresponding resolvents on the real axis at high frequency, and as a consequence, we obtain free of eigenvalues regions. As an application, we get exponential decay of the energy of the solutions of the correpsonding mixed boundary value problems.
Boundary layers for transmission problems with singularities
Abderrahman Maghnouji,Serge Nicaise
Electronic Journal of Differential Equations , 2006,
Abstract: We study two-dimensional transmission problems for the Laplace operator for two diffusion coefficients. We describe the boundary layers of this problem and show that the layers appear only in the part where the coefficient is large. The relationship with the singularities of the limit problem is also described.
Epigenetic transgenerational inheritance of somatic transcriptomes and epigenetic controlregions
Michael K Skinner, Mohan Manikkam, Md M Haque, Bin Zhang, Marina I Savenkova
Genome Biology , 2012, DOI: 10.1186/gb-2012-13-10-r91
Abstract: Investigation of different tissue transcriptomes in male and female F3 generation vinclozolin versus control lineage rats demonstrated all tissues examined had transgenerational transcriptomes. The microarrays from 11 different tissues were compared with a gene bionetwork analysis. Although each tissue transgenerational transcriptome was unique, common cellular pathways and processes were identified between the tissues. A cluster analysis identified gene modules with coordinated gene expression and each had unique gene networks regulating tissue-specific gene expression and function. A large number of statistically significant over-represented clusters of genes were identified in the genome for both males and females. These gene clusters ranged from 2-5 megabases in size, and a number of them corresponded to the epimutations previously identified in sperm that transmit the epigenetic transgenerational inheritance of disease phenotypes.Combined observations demonstrate that all tissues derived from the epigenetically altered germ line develop transgenerational transcriptomes unique to the tissue, but common epigenetic control regions in the genome may coordinately regulate these tissue-specific transcriptomes. This systems biology approach provides insight into the molecular mechanisms involved in the epigenetic transgenerational inheritance of a variety of adult onset disease phenotypes.Epigenetic transgenerational inheritance involves the germ line transmission of epigenetic marks between generations that alter genome activity and phenotype [1-3]. Environmental factors (for example, toxicants or nutrition) at a critical time during fetal gonadal sex-determination have been shown to alter DNA methylation programming of the germ line to promote the presence of imprinted-like sites that can be transmitted through the sperm to subsequent generations [1,4]. Animals derived from a germ line with an altered epigenome have been shown to develop adult-onset disease or abnor
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