Cloning and Expression of the Functional Human Anti-vascular Endothelial Growth Factor (VEGF) Using the pcDNA3.1 Vector and the Human Chronic Myelogenous Leukemia Cell Line K562

In this study, the light chain (κ) and heavy chain (γ) sequences of the monoclonal antibody against vascular endothelial growth factor (VEGF) were sub-cloned into the eukaryotic pcDNA3.1 (+) (Hygro) and the pcDNA3.1 (+) (Neo) expression vectors using the traditional and homologous recombination methods. To express the antibody, the recombinant plasmids were transfected into the Chinese hamster ovary (CHO) and the K562 cell lines. The recombinant antibody was then purified using the protein A affinity chromatography. Furthermore, in order to demonstrate the inhibition of VEGF-induced mitogenesis of the recombinant antibody, the bovine aorta endothelial like cells were employed. The results showed specialization and conjunction of the recombinant antibody to the VEGF. It was also indicated that the antibody expression in the K562 cell lines was higher than the CHO cell lines. Furthermore, the in vitro VEGF inhabitation of the recombinant antibodies which were produced from the K562 cell line, and the CHO cell line, were similar. This proved that the K562 cell line is a good substitute for the CHO cell line in the production of the recombinant antibodies.     

Bridging the gaps between research,policy and practice in low- and middle-income countries: a survey of researchers

Background

Many international statements have urged researchers, policy-makers and health care providers to collaborate in efforts to bridge the gaps between research, policy and practice in low- and middle-income countries. We surveyed researchers in 10 countries about their involvement in such efforts.

Methods

We surveyed 308 researchers who conducted research on one of four clinical areas relevant to the Millennium Development Goals (prevention of malaria, care of women seeking contraception, care of children with diarrhea and care of patients with tuberculosis) in each of 10 low- and middle-income countries (China, Ghana, India, Iran, Kazakhstan, Laos, Mexico, Pakistan, Senegal and Tanzania). We focused on their engagement in three promising bridging activities and examined system-level, organizational and individual correlates of these activities.

Results

Less than half of the researchers surveyed reported that they engaged in one or more of the three promising bridging activities: 27% provided systematic reviews of the research literature to their target audiences, 40% provided access to a searchable database of research products on their topic, and 43% established or maintained long-term partnerships related to their topic with representatives of the target audience. Three factors emerged as statistically significant predictors of respondents’ engagement in these activities: the existence of structures and processes to link researchers and their target audiences predicted both the provision of access to a database (odds ratio [OR] 2.62, 95% CI 1.30–5.27) and the establishment or maintenance of partnerships (OR 2.65, 95% CI 1.25–5.64); stability in their contacts predicted the provision of systematic reviews (OR 2.88, 95% CI 1.35–6.13); and having managers and public (government) policy-makers among their target audiences predicted the provision of both systematic reviews (OR 4.57, 95% CI 1.78–11.72) and access to a database (OR 2.55, 95% CI 1.20–5.43).

Interpretation

Our findings suggest potential areas for improvement in light of the bridging strategies targeted at health care providers that have been found to be effective in some contexts and the factors that appear to increase the prospects for using research in policy-making.The need to bridge the gaps between research, policy and practice appears to be a global phenomenon. Three recent, highly visible resolutions — the Mexico Action Statement on Health Research in 2004 (58 countries),¹ the related World Health Assembly resolution in 2005 (193 countries)² and the Bamako Call to Action on Research for Health in 2008 (53 countries) ³ — urged researchers, policy-makers and health care providers to collaborate in efforts to bridge these gaps. These efforts can range from bringing research-based evidence to the attention of those who could use it, to making research-based evidence available so that it can be readily retrieved when needed.We are not aware of a survey having been conducted in a range of low- and middle-income countries about researchers’ bridging activities related to specific high-priority health topics. Researchers and research organizations have been surveyed about their bridging activities in single high-income countries such as Canada.^4–6 Guideline-producing organizations and health technology assessment agencies have also been surveyed about their bridging activities;⁷ only in one case was the focus on bridging activities in low- and middle-income countries.⁸ Select research funding agencies have been studied in low- and middle-income countries.⁹ Yet the Millennium Development Goals and the goals of many countries call for topic-focused efforts to bridge the gaps between research, policy and practice.We studied efforts to bridge the gaps between research, policy and practice in 10 low- and middle-income countries (China, Ghana, India, Iran, Kazakhstan, Laos, Mexico, Pakistan, Senegal and Tanzania). In this article, we describe the findings from a survey of researchers in these countries who conducted research in one of four clinical areas relevant to the Millennium Development Goals: prevention of malaria (Ghana, Laos, Senegal and Tanzania), care of women seeking contraception (China, Kazakhstan, Laos and Mexico), care of children with diarrhea (Ghana, India, Pakistan and Senegal) and care of patients with tuberculosis (China, India, Iran and Mexico). In a related article, we describe the findings from a survey of health care providers in these countries who were practising in one of these clinical areas about their awareness of, access to and use of research-based evidence in these clinical areas and the influence of such evidence on their professional practice.¹⁰The challenges associated with documenting such efforts include cross-country differences in the capacity to conduct surveys of researchers; the visibility of researchers depending on their alignment with priorities of government, development agencies, research funding agencies and industry (and hence their likelihood of being identified to participate in these surveys); and researchers’ familiarity with and attitudes toward the bridging activities asked about in these surveys.     

Priming with oxytocin and relaxin improves cardiac differentiation of adipose tissue–derived stem cells

Previous studies have identified the heart as a source and a target tissue for oxytocin and relaxin hormones. These hormones play important roles in the regulation of cardiovascular function and repair of ischemic heart injury. In the current study, we examined the impact of oxytocin and relaxin on the development of cardiomyocytes from mesenchymal stem cells. For this purpose, mouse adipose tissue–derived stem cells (ADSCs) were treated with different concentrations of oxytocin or relaxin for 4 days. Three weeks after initiation of cardiac induction, differentiated ADSCs expressed cardiac-specific genes, Gata4, Mef2c, Nkx2.5, Tbx5, α- and β-Mhc, Mlc2v, Mlc2a and Anp, and cardiac proteins including connexin 43, desmin and α-actinin. 10 ⁻⁷ M oxytocin and 50 ng/mL relaxin induced the maximum upregulation in the expression of cardiac markers. A combination of oxytocin and relaxin induced cardiomyocyte differentiation more potently than the individual factors. In our experiment, oxytocin-relaxin combination increased the population of cardiac troponin I-expressing cells to 6.84% as compared with 2.36% for the untreated ADSCs, 3.7% for oxytocin treatment and 3.41% for relaxin treatment groups. In summary, the results of this study indicated that oxytocin and relaxin hormones individually and in combination can improve cardiac differentiation of ADSCs, and treatment of the ADSCs and possibly other mesenchymal stem cells with these hormones may enhance their cardiogenic differentiation and survival after transplantation into the ischemic heart tissue.     

Arachidonic acid alleviates the detrimental effects of acetylsalicylic acid on human granulosa cells performance in vitro

Here, we investigated the biological effects of arachidonic acid (AA) in human cumulus granulosa cells (CGCs) after exposure to ASA. Cells were isolated from the follicular fluid and incubated with 0.5 mM acetylsalicylic acid (ASA) and 50 µM AA. Cell viability was analyzed by 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide assay. E₂ and P₄ levels were measured by chemiluminescence assay. Expression of genes including CYP19A1, FACN, and SCD1 was measured by real‐time polymerase chain reaction assay. Oxidative status was analyzed by monitoring glutathione peroxidase activity. The fatty acid profile was analyzed by the gas chromatography technique. Enzyme‐linked immunosorbent assay was used to measure prostaglandin E₂ (PGE₂) in CGCs after exposure to ASA and AA. Protein levels of the estrogen receptor were studied by immunofluorescence staining. Ultrastructural changes were evaluated by transmission electron microscopy imaging. ASA treatment reduced E₂ production, Cyp19a1 expression, glutathione peroxidase (GPx) activity, and estradiol receptor expression in CGCs. The addition of AA prevented the ASA‐induced E₂ reduction (p < .05) and expression of Cyp19a1. Moreover, AA increased the antioxidant capacity of CGCs exposed to ASA by promoting GPx activity (p < .05). AA increased monounsaturated fatty acid/saturated fatty acid ratio compared with the ASA group (p < .05). AA supplementation triggered the synthesis and secretion of PGE₂ in ASA‐treated CGCS (p < .05). Cytoplasmic vacuolation observed in the ASA group and treatment with AA intensified vacuolation rate. The expression of the estrogen receptor was increased after AA supplementation. Data demonstrated that AA decreased the detrimental effects of ASA on human CGCs after 72 hr.     

Circulating HSPs Levels and Risk of Human Gastrointestinal Related Cancers: A Systematic Review and Meta-analysis

International Journal of Peptide Research and Therapeutics - Heat shock proteins (HSPs) have over-expression in the human malignancies. However, many studies reported inconsistent results. The...     

Novel method for detection probability and estimating population size of mountain frog,Rana macrocnemis (Boulenger, 1885) at the end of its distribution range

Landscape and Ecological Engineering - Local amphibian populations at the edge of a species range are possibly of greater conservation concern than any other amphibians group. They experience...     

Electric field effect on the zigzag (6,0) single-wall BC2N nanotube for use in nano-electronic circuits

We have analyzed the effect of external electric field on the zigzag (6,0) single-wall BC₂N nanotube using density functional theory calculations. Analysis of the structural parameters indicates that the nanotube is resistant against the external electric field strengths. Analysis of the electronic structure of the nanotube indicates that the applied parallel electric field strengths have a much stronger interaction with the nanotube with respect to the transverse electric field strengths and the nanotube is easier to modulate by the applied parallel electric field. Our results show that the properties of the nanotube can be controlled by the proper external electric field for use in nano-electronic circuits.

Antibody humanization methods – a review and update

This article reviews recent advances achieved during recent years on various aspects of antibody humanization theories and techniques. Common methods for producing humanized antibodies including framework-homology-based humanization, germline humanization, complementary determining regions (CDR)-homology-based humanization and specificity determining residues (SDR) grafting, as well as advantages and disadvantages of each of these methods and their applications are discussed.     

A new lichenicolous teleomorph is related to plant pathogens in Laetisaria and Limonomyces (Basidiomycota, Corticiales)

Molecular and morphological data were used to assess the taxonomic placement of an undescribed lichenicolous basidiomycete teleomorph collected in Luxembourg, Belgium and Germany. The new species is ecologically and morphologically similar to Marchandiobasidium aurantiacum, teleomorph of the common bulbilliferous lichen pathogen Marchandiomyces aurantiacus. However phylogenetic analysis of nuclear and mitochondrial rDNA sequences indicated a close relationship of the new species-not to M. aurantiacum but to turf grass pathogens in genera Laetisaria and Limonomyces, including the generic type of Laetisaria. We are including the new species in Laetisaria based on strong statistical support for the clade containing these teleomorphs and several Marchandiomyces anamorphs. The morphological and ecological diversity of this clade indicates a potentially significant evolutionary role played by lichen-associated species in the Corticiales.     

Autosomal recessive mental retardation: homozygosity mapping identifies 27 single linkage intervals, at least 14 novel loci and several mutation hotspots

Mental retardation (MR) has a worldwide prevalence of around 2% and is a frequent cause of severe disability. Significant excess of MR in the progeny of consanguineous matings as well as functional considerations suggest that autosomal recessive forms of MR (ARMR) must be relatively common. To shed more light on the causes of autosomal recessive MR (ARMR), we have set out in 2003 to perform systematic clinical studies and autozygosity mapping in large consanguineous Iranian families with non-syndromic ARMR (NS-ARMR). As previously reported (Najmabadi et al. in Hum Genet 121:43-48, 2007), this led us to the identification of 12 novel ARMR loci, 8 of which had a significant LOD score (OMIM: MRT5-12). In the meantime, we and others have found causative gene defects in two of these intervals. Moreover, as reported here, tripling the size of our cohort has enabled us to identify 27 additional unrelated families with NS-ARMR and single-linkage intervals; 14 of these define novel loci for non-syndromic ARMR. Altogether, 13 out of 39 single linkage intervals observed in our cohort were found to cluster at 6 different loci on chromosomes, i.e., 1p34, 4q27, 5p15, 9q34, 11p11-q13 and 19q13, respectively. Five of these clusters consist of two significantly overlapping linkage intervals, and on chr 1p34, three single linkage intervals coincide, including the previously described MRT12 locus. The probability for this distribution to be due to chance is only 1.14 × 10(-5), as shown by Monte Carlo simulation. Thus, in contrast to our previous conclusions, these novel data indicate that common molecular causes of NS-ARMR do exist, and in the Iranian population, the most frequent ones may well account for several percent of the patients. These findings will be instrumental in the identification of the underlying genes.