Immortalization of mouse myogenic cells can occur without loss of p16(INK4a), p19(ARF), or p53 and is accelerated by inactivation of Bax

BACKGROUND: Upon serial passaging of mouse skeletal muscle cells, a small number of cells will spontaneously develop the ability to proliferate indefinitely while retaining the ability to differentiate into multinucleate myotubes. Possible gene changes that could underlie myogenic cell immortalization and their possible effects on myogenesis had not been examined. RESULTS: We found that immortalization occurred earlier and more frequently when the myogenic cells lacked the pro-apoptotic protein Bax. Furthermore, myogenesis was altered by Bax inactivation as Bax-null cells produced muscle colonies with more nuclei than wild-type cells, though a lower percentage of the Bax-null nuclei were incorporated into multinucleate myotubes. In vivo, both the fast and slow myofibers in Bax-null muscles had smaller cross-sectional areas than those in wild-type muscles. After immortalization, both Bax-null and Bax-positive myogenic cells expressed desmin, retained the capacity to form multinucleate myotubes, expressed p19(ARF )protein, and retained p53 functions. Expression of p16(INK4a), however, was found in only about half of the immortalized myogenic cell lines. CONCLUSIONS: Mouse myogenic cells can undergo spontaneous immortalization via a mechanism that can include, but does not require, loss of p16(INK4a), and also does not require inactivation of p19(ARF )or p53. Furthermore, loss of Bax, which appears to be a downstream effector of p53, accelerates immortalization of myogenic cells and alters myogenesis

Coloquio Nacional a diez años de la Ley Federal de Educación

Organizado por la Escuela de Ciencias de la Educación, la Secretaría de Extensión de la Facultad de Filosofía y Humanidades de la Universidad Nacional de Córdoba y el Equipo de Investigación de la Cátedra de Organización y Administración Educacional, se desarrolló un coloquio que nucleó a 250 investigadores de Universidades e Institutos de Formación Docente de todo el país, con el objetivo de realizar un balance de la implementación de la reforma educativa iniciada con la Ley Federal de Educación (LFE). Al cumplirse diez años de su sanción y poniendo entre signos de interrogación el lema que acompañó a la reforma: Mejor Educación para todos se expusieron gran cantidad de trabajos referidos a su implementación en las jurisdicciones. En general las presentaciones revistieron un tono crítico respecto a varias cuestiones básicas de la Ley y la Reforma

Efecto de la invasión de acacia negra (<i>Gleditsia triacanthos</i> L.) sobre arroyos pampeanos

Pampean fluvial ecosystems of low order usually lack of riparian vegetation. In recent years the invasion of honey locust (Gleditsia triacanthos L.) has caused changes in landscape composition. The aim of this study was to evaluate the effect of honey locust invasion on pampean streams. Three reaches with different degree of invasion were selected and compared with three control reaches with no canopy. In order to evaluate the effect of invasion, nutrients (soluble reactive phosphorus, ammonium and nitrates), biomass of producers (seston, macrophytes, periphyton and phytobenthos) and net production in each reach were determined. Significant differences were observed for all of variables estimated between reaches with and without canopy, but not in all cases. The amount of variables with significant differences between both reaches rises following a gradient of increasing invasion levels. Furthermore, differences are more pronounced with increasing percentage of honey locust coverage on the stream. We conclude that sustained invasion of honey locust modifies the concentration of nutrients in water, the biomass of some communities and the production of these communities. This effect could be avoided with early management of the invasion of honey locust.Facultad de Ciencias Naturales y Muse

Efecto de la invasión de acacia negra (<i>Gleditsia triacanthos</i> L.) sobre arroyos pampeanos

Pampean fluvial ecosystems of low order usually lack of riparian vegetation. In recent years the invasion of honey locust (Gleditsia triacanthos L.) has caused changes in landscape composition. The aim of this study was to evaluate the effect of honey locust invasion on pampean streams. Three reaches with different degree of invasion were selected and compared with three control reaches with no canopy. In order to evaluate the effect of invasion, nutrients (soluble reactive phosphorus, ammonium and nitrates), biomass of producers (seston, macrophytes, periphyton and phytobenthos) and net production in each reach were determined. Significant differences were observed for all of variables estimated between reaches with and without canopy, but not in all cases. The amount of variables with significant differences between both reaches rises following a gradient of increasing invasion levels. Furthermore, differences are more pronounced with increasing percentage of honey locust coverage on the stream. We conclude that sustained invasion of honey locust modifies the concentration of nutrients in water, the biomass of some communities and the production of these communities. This effect could be avoided with early management of the invasion of honey locust.Facultad de Ciencias Naturales y Muse

Organizational factors associated with readiness to implement and translate a primary care based telemedicine behavioral program to improve blood pressure control: the HTN-IMPROVE study

Abstract Background Hypertension is prevalent and often sub-optimally controlled; however, interventions to improve blood pressure control have had limited success. Objectives Through implementation of an evidence-based nurse-delivered self-management phone intervention to facilitate hypertension management within large complex health systems, we sought to answer the following questions: What is the level of organizational readiness to implement the intervention? What are the specific facilitators, barriers, and contextual factors that may affect organizational readiness to change? Study design Each intervention site from three separate Veterans Integrated Service Networks (VISNs), which represent 21 geographic regions across the US, agreed to enroll 500 participants over a year with at least 0.5 full time equivalent employees of nursing time. Our mixed methods approach used a priori semi-structured interviews conducted with stakeholders (n = 27) including nurses, physicians, administrators, and information technology (IT) professionals between 2010 and 2011. Researchers iteratively identified facilitators and barriers of organizational readiness to change (ORC) and implementation. Additionally, an ORC survey was conducted with the stakeholders who were (n = 102) preparing for program implementation. Results Key ORC facilitators included stakeholder buy-in and improving hypertension. Positive organizational characteristics likely to impact ORC included: other similar programs that support buy-in, adequate staff, and alignment with the existing site environment; improved patient outcomes; is positive for the professional nurse role, and is evidence-based; understanding of the intervention; IT infrastructure and support, and utilization of existing equipment and space. The primary ORC barrier was unclear long-term commitment of nursing. Negative organizational characteristics likely to impact ORC included: added workload, competition with existing programs, implementation length, and limited available nurse staff time; buy-in is temporary until evidence shows improved outcomes; contacting patients and the logistics of integration into existing workflow is a challenge; and inadequate staffing is problematic. Findings were complementary across quantitative and qualitative analyses. Conclusions The model of organizational change identified key facilitators and barriers of organizational readiness to change and successful implementation. This study allows us to understand the needs and challenges of intervention implementation. Furthermore, examination of organizational facilitators and barriers to implementation of evidence-based interventions may inform dissemination in other chronic diseases.http://deepblue.lib.umich.edu/bitstream/2027.42/112820/1/13012_2013_Article_683.pd

Efecto de la invasión de acacia negra (<i>Gleditsia triacanthos</i> L.) sobre arroyos pampeanos

Pampean fluvial ecosystems of low order usually lack of riparian vegetation. In recent years the invasion of honey locust (Gleditsia triacanthos L.) has caused changes in landscape composition. The aim of this study was to evaluate the effect of honey locust invasion on pampean streams. Three reaches with different degree of invasion were selected and compared with three control reaches with no canopy. In order to evaluate the effect of invasion, nutrients (soluble reactive phosphorus, ammonium and nitrates), biomass of producers (seston, macrophytes, periphyton and phytobenthos) and net production in each reach were determined. Significant differences were observed for all of variables estimated between reaches with and without canopy, but not in all cases. The amount of variables with significant differences between both reaches rises following a gradient of increasing invasion levels. Furthermore, differences are more pronounced with increasing percentage of honey locust coverage on the stream. We conclude that sustained invasion of honey locust modifies the concentration of nutrients in water, the biomass of some communities and the production of these communities. This effect could be avoided with early management of the invasion of honey locust.Facultad de Ciencias Naturales y Muse

Differential binding of Escherichia coli McrA protein to DNA sequences that contain the dinucleotide m5CpG

The Escherichia coli McrA protein, a putative C5-methylcytosine/C5-hydroxyl methylcytosine-specific nuclease, binds DNA with symmetrically methylated HpaII sequences (Cm5CGG), but its precise recognition sequence remains undefined. To determine McrA’s binding specificity, we cloned and expressed recombinant McrA with a C-terminal StrepII tag (rMcrA-S) to facilitate protein purification and affinity capture of human DNA fragments with m5C residues. Sequence analysis of a subset of these fragments and electrophoretic mobility shift assays with model methylated and unmethylated oligonucleotides suggest that N(Y > R) m5CGR is the canonical binding site for rMcrA-S. In addition to binding HpaII-methylated double-stranded DNA, rMcrA-S binds DNA containing a single, hemimethylated HpaII site; however, it does not bind if A, C, T or U is placed across from the m5C residue, but does if I is opposite the m5C. These results provide the first systematic analysis of McrA’s in vitro binding specificity

Seroepidemiology of human Toxoplasma gondii infection in China

<p>Abstract</p> <p>Background</p> <p>Toxoplasmosis is an important zoonotic parasitic disease worldwide. In immune competent individuals, <it>Toxoplasma gondii </it>preferentially infects tissues of central nervous systems, which might be an adding factor of certain psychiatric disorders. Congenital transmission of <it>T. gondii </it>during pregnancy has been regarded as a risk factor for the health of newborn infants. While in immune-compromised individuals, the parasite can cause life-threatening infections. This study aims to investigate the prevalence of <it>T. gondii </it>infection among clinically healthy <b>i</b>ndividuals and patients with psychiatric disorders in China and to identify the potential risk factors related to the vulnerability of infection in the population.</p> <p>Methods</p> <p>Serum samples from 2634 healthy individuals and 547 patients with certain psychiatric disorders in Changchun and Daqing in the northeast, and in Shanghai in the south of China were examined respectively for the levels of anti-<it>T. gondii </it>IgG by indirect ELISA and a direct agglutination assay. Prevalence of <it>T. gondii </it>infection in the Chinese population in respect of gender, age, residence and health status was systematically analyzed.</p> <p>Results</p> <p>The overall anti-<it>T. gondii </it>IgG prevalence in the study population was 12.3%. In the clinically healthy population 12.5% was sero-positive and in the group with psychiatric disorders 11.3% of these patients were positive with anti-<it>T. gondii </it>IgG. A significant difference (P = 0.004) was found between male and female in the healthy population, the seroprevalence was 10.5% in men versus 14.3% in women. Furthermore, the difference of <it>T. gondii </it>infection rate between male and female in the 20-19 year's group was more obvious, with 6.4% in male population and 14.6% in female population.</p> <p>Conclusion</p> <p>A significant higher prevalence of <it>T. gondii </it>infection was observed in female in the clinically healthy population. No correlation was found between <it>T. gondii </it>infection and psychiatric disorders in this study. Results suggest that women are more exposed to <it>T. gondii </it>infection than men in China. The data argue for deeper investigations for the potential risk factors that threat the female populations.</p