Gene transfection of HEK cells on supermacroporous polyacrylamide monoliths: a comparison of transient and stable recombinant protein expression in perfusion culture

Transient and continuous recombinant protein expression by HEK cells was evaluated in a perfused monolithic bioreactor. Highly porous synthetic cryogel scaffolds (10ml bed volume) were characterised by scanning electron microscopy and tested as cell substrates. Efficient seeding was achieved (94% inoculum retained, with 91-95% viability). Metabolite monitoring indicated continuous cell growth, and endpoint cell density was estimated by genomic DNA quantification to be 5.2x108, 1.1x109 and 3.5x1010 at day 10, 14 and 18. Culture of stably transfected cells allowed continuous production of the Drosophila cytokine Spätzle by the bioreactor at the same rate as in monolayer culture (total 1.2 mg at d18) and this protein was active. In transient transfection experiments more protein was produced per cell compared with monolayer culture. Confocal microscopy confirmed homogenous GFP expression after transient transfection within the bioreactor. Monolithic bioreactors are thus shown to be a flexible and powerful tool for manufacturing recombinant proteins

Life course socioeconomic position and body composition in adulthood: a systematic review and narrative synthesis

INTRODUCTION: Multiple systematic reviews have investigated the relation between socioeconomic position (SEP) and body mass index (BMI) throughout the life course. However, BMI does not capture quantity and distribution of fat and muscle, which are better indicators of obesity than BMI, and have been independently linked to adverse health outcomes. Less is known about the relation between SEP and body composition, and the literature has not been reviewed. We therefore systematically reviewed the literature on the association between life course SEP and body composition in adulthood. METHODS: A protocol was registered on PROSPERO (CRD42019119937), and the review followed PRISMA guidelines. An electronic search of three databases (MEDLINE, Embase Classic + Embase and SPORTDiscus) was conducted. Original studies in the English language were included that examine the association between any recognised measure of SEP at any age and body composition (fat mass, fat-free mass, ratio and distribution) in adulthood, measured using a direct technique, i.e., not an anthropometric measure. A narrative synthesis was conducted. RESULTS: A total of 47 papers were included in the final review, none were from low-income countries (LICs). Greater advantage in childhood and adulthood was associated with lower fat levels in high-income countries (HICs). Associations in the opposite direction were found exclusively in middle-income countries (MICs). No studies in MICs reported associations for childhood SEP. For measures of lean mass, the majority of papers reported no association, or greater advantage in adulthood associated with higher lean mass, with little variation between HICs and MICs. Associations in HICs are more often observed in women than men. CONCLUSION: The results indicate that fat measures follow similar patterns to those seen for BMI, and that women in HICs are more likely to experience inequalities in both fat and lean measures. Further research in LICs and MICs is needed

Seasonal variation in agglutination of Plasmodium falciparum-infected erythrocytes

Abstract. Agglutination and rosette formation are in vitro characteristics of Plasmodium falciparum–infected erythrocytes, which have been associated with host protective immune responses and also with parasite virulence. The present study was carried out in an area of seasonal and unstable malaria transmission in eastern Sudan. Plasma samples were obtained before, during, and after the transmission season from a volunteer cohort of 64 individuals seven years of age and older. These plasmas were assayed for their ability to agglutinate cultured parasitized eryth-rocytes originally obtained from acute malaria infection samples taken from five of the cohort members. Our data show that the capacity of donor plasma samples to agglutinate parasitized cells depended largely on the time of sampling relative to the transmission season, at least within this epidemiologic setting. Thus, although less than half of the pretransmission season samples could agglutinate any of the five lines of cultured parasites, all post-transmission season samples could agglutinate at least one of the parasite lines, with 74 % agglutinating two or more lines. This increase in the agglutination capacity of individual plasma samples after the transmission season occurred essentially regardless of whether an individual had experienced a clinical malaria attack during the transmission season. The study thus confirms the acquisition of agglutinating antibodies following episodes of clinical malaria, but also dem-onstrates that such acquisition can take place in the absence of disease, presumably as a consequence of subclinica

Socioeconomic position and body composition in childhood in high- and middle-income countries: a systematic review and narrative synthesis

BACKGROUND: The relation between socioeconomic position (SEP) and obesity measured by body mass index (BMI), a measure of weight for height, has been extensively reviewed in children, showing consistent associations between disadvantaged SEP and higher BMI in high-income countries (HICs) and lower BMI in middle-income countries (MICs). Fat mass (FM), a more accurate measure of adiposity, and fat-free mass (FFM) are not captured by BMI, but have been shown to track from childhood to adulthood, and be important for cardiovascular health and functional outcomes in later life. It is not clear whether body composition is associated with SEP. We systematically reviewed the association between SEP and body composition in childhood. METHODS: A systematic review was carried out following PRISMA guidelines. The protocol was pre-registered with PROSPERO (CRD42019119937). Original studies in the English language, which examined the association between SEP and body composition in childhood, were included. An electronic search of three databases was conducted. Two independent reviewers carried out screening, data extraction and quality assessment. Due to heterogeneity in results, a narrative synthesis was conducted. Heterogeneity in findings according to SEP, sex, body composition measure and country income level was investigated. RESULTS: 50 papers were included, the majority from HICs. No papers were from low-income countries. Disadvantage in childhood was associated with greater FM and lower FFM in HICs, but with lower FM and lower FFM in MICs. When measures of FFM indexed to height were used there was no evidence of associations with SEP. In HICs, more studies reported associations between disadvantaged SEP and higher FM among girls comparative to boys. CONCLUSIONS: Inequalities in FM are evident in HICs and, in the opposite direction, in MICs and follow similar trends to inequalities for BMI. Inequalities in height are likely important in understanding inequalities in FFM

Girls’ and women’s education within Unesco and the World Bank, 1945–2000

By 2000, girls’ and women’s education was a priority for international development organisations. While studies have examined the impact of recent campaigns and programmes, there has been less exploration of ideas about girls’ and women’s education within development thought in the immediate post?colonial period, and the political mechanisms through which this came to be a global concern. Through a study of policy documents, this paper investigates how the education of girls and women came to be prioritised within the two principle UN agencies involved with education since 1945, the World Bank and Unesco. A shift in priorities is evident, from ensuring formal rights and improving the status of women, to expanding the productive capacities of women, fertility control and poverty reduction. While the ascendance of human capital theory provided a space for a new perception of the role of women’s education in development, in other policy arenas women’s education was central to exploring more substantive, rights?based notions of gender equality. Ultimately, the goal of improving girls’ and women’s education fitted into diverse development agendas, paving the way for it to become a global development priority

High Depth-of-Discharge Zinc Rechargeability Enabled by a Self-Assembled Polymeric Coating

Zinc has the potential for widespread use as an environmentally friendly and cost-effective anode material pending the resolution of rechargeability issues caused by active material loss and shape change. Here, a self-assembled Nafion-coated Celgard 3501 (NC-Celgard) separator is shown to enable unprecedented cycle life of a Zn anode in alkaline electrolyte at high depth-of-discharge (DODZn). Using commercially relevant energy-dense electrodes with high areal capacities of 60 mAh cm–2, Zn–Ni cells tested at 20% DODZn cells achieve over 200 cycles while 50% DODZn cells achieve over 100 cycles before failure. The 20% and 50% DOD cells deliver an average of 132 and 180 Wh L–1 per cycle over their lifetime respectively. Rechargeability is attributed to the highly selective diffusion properties of the 300 nm thick negatively charged Nafion coating on the separator which prevents shorting by dendrites and inhibits redistribution of the active material. Crossover experiments show that the NC-Celgard separator is practically impermeable to zincate ([Zn(OH)4]2–), outperforming commercial Celgard, cellophane, Nafion 211 and 212 separators while still allowing hydroxide transport. This work demonstrates the efficacy of selective separators for increasing the cycle life of energy-dense Zn electrodes without adding significant volume or complexity to the system

An Estimation of the Entomological Inoculation Rate for Ifakara: A Semi-Urban Area in a Region of Intense Malaria Transmission in Tanzania.

An entomological study on vectors of malaria and their relative contribution to Plasmodium falciparum transmission in the semi-urban area of Ifakara, south-eastern Tanzania, was conducted. A total of 32 houses were randomly sampled from the area and light trap catches (LTC) performed in one room in each house every 2 weeks for 1 year. A total of 147 448 mosquitoes were caught from 789 LTC; 26 134 Anopheles gambiae s.l., 615 A. funestus, 718 other anophelines and 119 981 culicines. More than 60% of the total A. gambiae s.l. were found in five (0.6%) LTCs, with a maximum of 5889 caught in a single trap. Of 505 A. gambiae s.l. speciated by polymerase chain reaction, 91.5% were found to be A. arabiensis. Plasmodium falciparum sporozoite enzyme-linked immunosorbent assay tests were performed on 10 108 anopheles mosquitoes and 39 (0.38%) were positive. Entomological inoculation rate (EIR) estimates were generated using a standard method and an alternative method that allows the calculation of confidence intervals based on a negative binomial distribution of sporozoite positive mosquitoes. Overall EIR estimates were similar; 31 vs. 29 [95% confidence interval (CI): 19, 44] infectious bites per annum, respectively. The EIR ranged from 4 (95% CI: 1, 17) in the cool season to 108 (95% CI: 69, 170) in the wet season and from 54 (95% CI: 30, 97) in the east of the town to 15 (95% CI: 8, 30) in the town centre. These estimates show large variations over short distances in time and space. They are all markedly lower than those reported from nearby rural areas and for other parts of Tanzania