bluuebunny/crossref_metadata_2025_split huggingface dataset:
Heterotrophic growth of Neochloris oleoabundans using glucose as a carbon source
Authors: Morales-Sánchez Daniela , Tinoco-Valencia Raunel , Kyndt John , Martinez Alfredo 
Published: July 2013

Abstract

Background
In comparison with phototrophic growth, heterotrophic conditions can significantly increase growth rates, final cell number and cell mass in microalgae cultures. Neochloris oleoabundans is a microalga of biotechnological interest that accumulates lipids under phototrophic and nitrogen-limited conditions. Heterotrophic flask culture experiments were conducted to identify carbon sources that can be metabolized by N. oleoabundans, and bioreactor batch and fed-batch (nitrate pulse additions) cultures supplemented with glucose were performed to study the cellular composition of the microalgae under balanced and high C/N ratios (glucose/nitrate).

Results

N. oleoabundans was able to grow using glucose and cellobiose as sole carbon sources under strict heterotrophic conditions. Under a balanced C/N ratio of 17 and using bioreactor batch cultures containing 3 g/L glucose, a maximal cell mass of 1.72 g/L was found, with protein being the major cell component (44% w/w). A maximal cell mass of 9.2 g/L was obtained using batch cultures at a C/N ratio of 278. Under these conditions, lipid accumulation was promoted (up to 52% w/w) through N-limitation, resulting in high lipid productivity (528.5 mg/L/day). Fed-batch cultures were performed at a C/N ratio of 278 and with nitrate pulse additions. This condition allowed a maximal cell mass of 14.2 g/L to be achieved and switched the metabolism to carbohydrate synthesis (up to 54% of dry weight), mainly in the form of starch. It was found that transmembrane transport under these conditions was dependent on a proton-motive force, indicating that glucose is transported by a symporter.

Conclusions

N. oleoabundans was able to grow under strict heterotrophic culture conditions with glucose or cellobiose as the only carbon source. The glucose used is transported by a symporter system. Batch cultures with a balanced C/N ratio accumulate proteins as the major cellular component; a high C/N ratio significantly increased the dry cell mass and resulted in a high lipid content, and a high cell density was achieved using fed-batch cultures promoting carbohydrate accumulation. These results suggest heterotrophic batch cultures of N. oleoabundans as an alternative for the production of proteins or lipids with simple culture strategies and minimal-mineral media supplemented with glucose.
Stability and change in the distribution of cytospecies of the Simulium damnosum complex (Diptera: Simuliidae) in southern Ghana from 1971 to 2011
Authors: Post Rory J , Cheke Robert A , Boakye Daniel A , Wilson Michael D , Osei-Atweneboana Mike Y , Tetteh-Kumah Anthony , Lamberton Poppy HL , Crainey J Lee , Yaméogo Laurent , Basáñez María-Gloria 
Published: July 2013

Abstract

Background

Simulium damnosum s.l., the most important vector of onchocerciasis in Africa, is a complex of sibling species that have been described on the basis of differences in their larval polytene chromosomes. These (cyto) species differ in their geographical distributions, ecologies and epidemiological roles. In Ghana, distributional changes have been recorded as a consequence of vector control and environmental change (e.g. deforestation), with potential disease consequences. We review the distribution of cytospecies in southern Ghana and report changes observed with reference to historical data collated from 1971 to 2005 and new identifications made between 2006 and 2011.

Methods/Results
Larvae were collected from riverine breeding sites, fixed in Carnoy’s solution and chromosome preparations made. Cytotaxonomic identifications from 1,232 samples (including 49 new samples) were analysed. We report long-term stability in cytospecies distribution in the rivers Afram, Akrum, Pawnpawn and Pru. For the rivers Oda, Ofin and Tano we describe (for the first time) patterns of distribution. We could not detect cytospecies composition changes in the upper Pra, and the lower Pra seems to have been stable. The elimination of the Djodji form of S. sanctipauli in the Volta Region seems to have had no long-term effects on the distribution of the other cytospecies, despite an initial surge by S. yahense. There has been a recent increase in the occurrence of savannah cytospecies in the river Asukawkaw, and this might be related to continuing deforestation.

Conclusions
Cytospecies’ distributions have not been stable from 1971 to 2011. Although there are no obvious causes for the temporary appearance and subsequent disappearance of cytospecies in a particular location, a major influence has been vector control and migration patterns, probably explaining observed changes on the Black Volta and lower Volta rivers. Deforestation was previously implicated in an increase of savannah cytospecies in southern Ghana (1975–1997). Our data had little power to support (or refute) suggestions of a continuing increase, except in the Asukawkaw river basin.
A comparison of the Doppler ultrasound interpretation by student and registered podiatrists
Authors: Young Maria , Birch Ivan , Potter Chloe Alexa , Saunders Robert , Otter Simon , Hussain Shahin , Pellett Jane , Reynolds Nadine , Jenkin Sarah , Wright Wendy 
Published: July 2013

AbstractBackgroundHand held Doppler ultrasound machines are routinely used by podiatrists to assess the arterial perfusion of the lower limb. They are practical, painless and effective as a screening tool, and the available general evidence would suggest that interpretation by practitioners is reliable. This study compared the abilities of student and Health and Care Professions Council (HCPC) registered podiatrists to identify correctly Doppler ultrasound outputs.MethodA prospective single blind comparative study design was utilised. Fifteen Doppler recordings of the blood flow in the posterior tibial artery, five each of monophasic, biphasic and triphasic blood flow, were used to compare the interpretation abilities of 30 undergraduate podiatry students and 30 HCPC registered podiatrists. Chi‐squared analysis of the results was undertaken.ResultsChi‐squared analysis found that there was no statistically significant difference between the overall abilities of student podiatrists and HCPC registered podiatrists to identify correctly Doppler ultrasound recordings (p = 0.285). No significant difference was found in their ability to identify Doppler ultrasound recordings of monophasic, biphasic or triphasic blood flow (p > 0.050).ConclusionThe results of this relatively small study suggest that both student and HCPC registered podiatrists are in general able to identify the nature of blood flow based on the output of handheld Doppler ultrasound units. However, the results raise an issue regarding professional development of practitioners who might have been expected to have enhanced their skills of Doppler ultrasound sound identification since professional registration.
Creation of a Merkel cell polyomavirus small T antigen-expressing murine tumor model and a DNA vaccine targeting small T antigen
Authors: Gomez Bianca , He Liangmei , Tsai Ya Chea , Wu T-C , Viscidi Raphael P , Hung Chien-Fu 
Published: July 2013

Abstract

Background
Merkel cell polyomavirus (MCPyV) is a DNA virus expressing transcripts similar to the large T (LT) and small T (ST) transcripts of SV40, which has been implicated in the pathogenesis of Merkel cell carcinoma (MCC), a rare and highly aggressive neuroendocrine skin cancer. MCPyV LT antigen expression was found to be a requirement for MCC tumor maintenance and ST protein also likely contributes to the carcinogenesis of MCC. Previously, we have identified the probable immunodominant epitope of MCPyV LT and developed a DNA vaccine encoding this epitope linked to calreticulin. The LT-targeting DNA vaccine generated prolonged survival, decreased tumor size and increased LT-specific CD8+ T cells in tumor-bearing mice.

Results
In this study, we developed a MCPyV ST-expressing tumor cell line from B16 mouse melanoma cells. We then utilized this ST-expressing tumor cell line to test the efficacy of a DNA vaccine encoding ST. In ST-expressing tumor-bearing mice, this vaccine, pcDNA3-MCC/ST, generated a significant number of ST antigenic peptide-specific CD8+ T cells and experienced markedly enhanced survival compared to mice vaccinated with empty vector.

Conclusions
The formation of an effective vaccine against MCPyV has the potential to advance the field of MCC therapy and may contribute to the control of this severe malignancy through immunotherapy. Both of the innovative technologies presented here provide opportunities to develop and test MCPyV-targeted therapies for the control of Merkel cell carcinoma.
Simplified programming and control of automated radiosynthesizers through unit operations
Authors: Claggett Shane B , Quinn Kevin M , Lazari Mark , Moore Melissa D , van Dam R Michael 
Published: July 2013

Abstract

Background
Many automated radiosynthesizers for producing positron emission tomography (PET) probes provide a means for the operator to create custom synthesis programs. The programming interfaces are typically designed with the engineer rather than the radiochemist in mind, requiring lengthy programs to be created from sequences of low-level, non-intuitive hardware operations. In some cases, the user is even responsible for adding steps to update the graphical representation of the system. In light of these unnecessarily complex approaches, we have created software to perform radiochemistry on the ELIXYS radiosynthesizer with the goal of being intuitive and easy to use.

Methods
Radiochemists were consulted, and a wide range of radiosyntheses were analyzed to determine a comprehensive set of basic chemistry unit operations. Based around these operations, we created a software control system with a client–server architecture. In an attempt to maximize flexibility, the client software was designed to run on a variety of portable multi-touch devices. The software was used to create programs for the synthesis of several 18F-labeled probes on the ELIXYS radiosynthesizer, with [18F]FDG detailed here. To gauge the user-friendliness of the software, program lengths were compared to those from other systems. A small sample group with no prior radiosynthesizer experience was tasked with creating and running a simple protocol.

Results
The software was successfully used to synthesize several 18F-labeled PET probes, including [18F]FDG, with synthesis times and yields comparable to literature reports. The resulting programs were significantly shorter and easier to debug than programs from other systems. The sample group of naive users created and ran a simple protocol within a couple of hours, revealing a very short learning curve. The client–server architecture provided reliability, enabling continuity of the synthesis run even if the computer running the client software failed. The architecture enabled a single user to control the hardware while others observed the run in progress or created programs for other probes.

Conclusions
We developed a novel unit operation-based software interface to control automated radiosynthesizers that reduced the program length and complexity and also exhibited a short learning curve. The client–server architecture provided robustness and flexibility.
A transgenic Xenopus laevis reporter model to study lymphangiogenesis
Authors: Ny Annelii , Vandevelde Wouter , Hohensinner Philipp , Beerens Manu , Geudens Ilse , Diez-Juan Antonio , Brepoels Katleen , Plaisance Stéphane , Krieg Paul A. , Langenberg Tobias , Vinckier Stefan , Luttun Aernout , Carmeliet Peter , Dewerchin Mieke 
Published: July 2013

Summary
The importance of the blood- and lymph vessels in the transport of essential fluids, gases, macromolecules and cells in vertebrates warrants optimal insight into the regulatory mechanisms underlying their development. Mouse and zebrafish models of lymphatic development are instrumental for gene discovery and gene characterization but are challenging for certain aspects, e.g. no direct accessibility of embryonic stages, or non-straightforward visualization of early lymphatic sprouting, respectively. We previously demonstrated that the Xenopus tadpole is a valuable model to study the processes of lymphatic development. However, a fluorescent Xenopus reporter directly visualizing the lymph vessels was lacking. Here, we created transgenic Tg(Flk1:eGFP) Xenopus laevis reporter lines expressing green fluorescent protein (GFP) in blood- and lymph vessels driven by the Flk1 (VEGFR-2) promoter. We also established a high-resolution fluorescent dye labeling technique selectively and persistently visualizing lymphatic endothelial cells, even in conditions of impaired lymph vessel formation or drainage function upon silencing of lymphangiogenic factors. Next, we applied the model to dynamically document blood and lymphatic sprouting and patterning of the initially avascular tadpole fin. Furthermore, quantifiable models of spontaneous or induced lymphatic sprouting into the tadpole fin were developed for dynamic analysis of loss-of-function and gain-of-function phenotypes using pharmacologic or genetic manipulation. Together with angiography and lymphangiography to assess functionality, Tg(Flk1:eGFP) reporter tadpoles readily allowed detailed lymphatic phenotyping of live tadpoles by fluorescence microscopy. The Tg(Flk1:eGFP) tadpoles represent a versatile model for functional lymph/angiogenomics and drug screening.
Insights into the osteoblast precursor differentiation towards mature osteoblasts induced by continuous BMP-2 signaling
Authors: Zouani Omar F. , Rami Lila , Lei Yifeng , Durrieu Marie-Christine 
Published: July 2013

Summary
Mature osteoblasts are the cells responsible for bone formation and are derived from precursor osteoblasts. However, the mechanisms that control this differentiation are poorly understood. In fact, unlike the majority of organs in the body, which are composed of “soft” tissue from which cells can easily be isolated and studied, the “hard” mineralized tissue of bone has made it difficult to study the function of bone cells. Here, we established an in vitro model that mimics this differentiation under physiological conditions. We obtained mature osteoblasts and characterized them on the basis of the following parameters: the strong expression of osteoblastic markers, such as Runx2 and Col-I; the achievement of specific dimensions (the cell volume increases 26-fold compared to the osteoblast precursors); and the production of an abundant extracellular matrix also called osteoid. We demonstrated that the differentiation of osteoblast precursors into mature osteoblasts requires the continuous activation of Bone Morphogenetic Protein (BMP) receptors, which we established with the immobilization of a BMP-2mimetic peptide on a synthetic matrix mimicking in vivo microenvironment. Importantly, we demonstrated that the organization of the F-actin network and acetylated microtubules of the cells were modified during the differentiation process. We showed that the perturbation of the F-actin cytoskeleton organization abolished the differentiation process. In addition, we demonstrated that expression of the Runx2 gene is required for this differentiation. These findings demonstrate the retro-regulation of cytoplasmic and genic components due to the continuous induction of BMP-2 and also provide more detailed insights into the correct signaling of BMPs for cell differentiation in bone tissue.
Fluorescently tagged Lin7c is a dynamic marker for polarity maturation in the zebrafish retinal epithelium
Authors: Luz Marta , Knust Elisabeth 
Published: July 2013

Summary
Development of epithelial cell polarity is a highly dynamic process, and often established by the sequential recruitment of conserved protein complexes, such as the Par or the Crumbs (Crb) complex. However, detailed insights into the refinement of polarity and the formation of the complexes are still lacking. Here, we established fluorescently tagged Lin7c, a core member of the Crb complex, as an ideal tool to follow development of polarity in zebrafish epithelia. We find that in gastrula stages, RFP-Lin7c is found in the cytosol of the enveloping layer, while Pard3-GFP is already polarized at this stage. During development of the retinal epithelium, RFP-Lin7c localization is refined from being cytosolic at 14 hours post fertilization (hpf) to almost entirely apical in cells of the eye cup at 28 hpf. This apical Lin7c localization depends on the Crb complex members Oko meduzy and Nagie oko. Thus, fluorescently tagged Lin7c can be used in a broad range of epithelia to follow polarity maturation in vivo and specifically to elucidate the sequence of events determining Crb complex-mediated polarity.
A multitude of people singing together
Authors: Wei Si 
Published: July 2013

Abstract
Among other things, city parks are places for people to relax or go for a walk in a natural and beautiful environment. Usually removed from the chaos of the city, parks often satisfy the desires of many city-dwellers for a place of natural beauty. Quite often, they are an integral part of a community. In Chinese parks, people do various activities freely in this natural space, such as physical exercise, tai chi, chess, dancing and singing. When music comes to this environment, it can bring cheer and laughter, and can give people precious opportunities to express their feelings and consider the meaning of life. Recently, singing has become a familiar phenomenon in Chinese parks. More and more people go to the park with their singing books. They spontaneously form chorus groups, organize singing activities and have even attracted the attention of the government. The Jingshan choir is the earliest and most influential extensive music group to meet in Chinese parks. Studying this group has helped me to gain a clearer understanding of why so many people in the community choose singing as their music activity.
The Rise of the Amplified Elephants
Authors: Hullick James 
Published: July 2013

Abstract
This project report charts the shift from leisure to an emerging vocational practice for the Amplified Elephants, a sonic art ensemble for people with intellectual disabilities based at the Footscray Community Arts Centre in Australia. The transition from sonic art making as recreation, then to leisure and then on to an emerging professional sonic art agenda for the Amplified Elephants has led to several insights regarding the role of music as leisure in the artistic development of people with an intellectual disability. The report discusses the creative processes of the group against a number of high-profile public outcomes that the Amplified Elephants have presented.
Higher free thyroxine levels are associated with all-cause mortality in euthyroid older men: the Health In Men Study
Authors: Yeap Bu B , Alfonso Helman , Hankey Graeme J , Flicker Leon , Golledge Jonathan , Norman Paul E , Chubb S A Paul 
Published: July 2013

ObjectiveThyroid dysfunction predicts poorer health outcomes, but the relationship between thyroid hormone levels within the reference range and mortality in older adults remains unclear. In this study, we examined the associations between the concentrations of free thyroxine (FT4) and TSH and all-cause mortality in older men without thyroid disease.Subjects and methodsWe performed a longitudinal study in community-dwelling men aged 70–89 years. Men with thyroid disease or taking thyroid-related medications were excluded. Baseline FT4and TSH levels were assayed. Incident deaths were ascertained using data linkage.ResultsThere were 3885 men without thyroid disease followed for (mean±s.d.) 6.4±1.5 years, during which time 837 had died (21.5%). Men who had died had higher baseline FT4levels (16.2±2.3 vs 15.8±2.1 pmol/l,P<0.001), but comparable TSH levels (2.4±1.5 vs 2.3±1.5 mIU/l,P=0.250). After accounting for age, smoking, physical factors and medical comorbidities, higher circulating FT4levels predicted all-cause mortality (quartile Q4 vs quartiles Q1–Q3: FT4levels ≥17.32 vs <17.32 pmol/l: adjusted hazard ratio (HR)=1.19, 95% CI=1.02–1.39,P=0.025). TSH levels did not predict mortality. After excluding men with subclinical hyperthyroidism or hypothyroidism, there were 3442 men and 737 who had died (21.4%). In these men, higher FT4levels remained independently associated with all-cause mortality (quartile Q4 vs quartiles Q1–Q3: adjusted HR=1.19, 95% CI=1.02–1.41,P=0.032).ConclusionsHigher FT4levels are associated with all-cause mortality in euthyroid older men, independently of conventional risk factors and medical comorbidities. Additional research is needed to determine whether or not this relationship is causal and to clarify the utility of thyroid function testing to stratify mortality risk in ageing men.
Models of Frequency-Dependent Selection with Mutation from Parental Alleles
Authors: Trotter Meredith V , Spencer Hamish G 
Published: July 2013

Abstract
Frequency-dependent selection (FDS) remains a common heuristic explanation for the maintenance of genetic variation in natural populations. The pairwise-interaction model (PIM) is a well-studied general model of frequency-dependent selection, which assumes that a genotype’s fitness is a function of within-population intergenotypic interactions. Previous theoretical work indicated that this type of model is able to sustain large numbers of alleles at a single locus when it incorporates recurrent mutation. These studies, however, have ignored the impact of the distribution of fitness effects of new mutations on the dynamics and end results of polymorphism construction. We suggest that a natural way to model mutation would be to assume mutant fitness is related to the fitness of the parental allele, i.e., the existing allele from which the mutant arose. Here we examine the numbers and distributions of fitnesses and alleles produced by construction under the PIM with mutation from parental alleles and the impacts on such measures due to different methods of generating mutant fitnesses. We find that, in comparison with previous results, generating mutants from existing alleles lowers the average number of alleles likely to be observed in a system subject to FDS, but produces polymorphisms that are highly stable and have realistic allele-frequency distributions.