Characterising B cell numbers and memory B cells in HIV infected and uninfected Malawian adults

BACKGROUND: Untreated human immunodeficiency virus (HIV) disease disrupts B cell populations causing reduced memory and reduced naïve resting B cells leading to increases in specific co-infections and impaired responses to vaccines. To what extent antiretroviral treatment reverses these changes in an African population is uncertain. METHODS: A cross-sectional study was performed. We recruited HIV-uninfected and HIV-infected Malawian adults both on and off antiretroviral therapy attending the Queen Elizabeth Central hospital in Malawi. Using flow cytometry, we enumerated B cells and characterized memory B cells and compared these measurements by the different recruitment groups. RESULTS: Overall 64 participants were recruited - 20 HIV uninfected (HIV-), 30 HIV infected ART naïve (HIV+N) and 14 HIV-infected ART treated (HIV+T). ART treatment had been taken for a median of 33 months (Range 12-60 months). Compared to HIV- the HIV+N adults had low absolute number of naïve resting B cells (111 vs. 180 cells/μl p = 0.008); reduced memory B cells (27 vs. 51 cells/μl p = 0.0008). The HIV+T adults had B-cell numbers similar to HIV- except for memory B cells that remained significantly lower (30 vs. 51 cells/μl p = 0.02). In the HIV+N group we did not find an association between CD4 count and B cell numbers. CONCLUSIONS: HIV infected Malawian adults have abnormal B-cell numbers. Individuals treated with ART show a return to normal in B-cell numbers but a persistent deficit in the memory subset is noted. This has important implications for long term susceptibility to co-infections and should be evaluated further in a larger cohort study

Critical agency and development: applying Freire and Sen to ICT4D in Zambia and Brazil

This paper draws upon critical theories and the capability approach. It argues for a conceptualization of development as a process designed to enable people to free themselves from structural disadvantage. Amartya Sen has argued that people’s “critical-agency” to question and reject unjust social norms is “pivotal” to human development and important for tackling inequalities of any kind. Freire’s critical pedagogy, and critical feminism, go further by providing disadvantaged people with the practical means to do this; to identify the structural root causes of unjust social norms and the critical-agency to challenge and change them. Two empirical case studies of ICT4D are presented, from Zambia and Brazil, which draw upon these critical approaches but use them in different ways. The paper argues that ICT4D must go beyond addressing people’s immediate practical needs for access to ICT tools and skills, to also address their strategic interest in identifying and tackling the root causes of disadvantage

Facilitating factors and barriers to malaria research utilization for policy development in Malawi

Research on various determinants of health is key in providing evidence for policy development, thereby leading to successful interventions. Utilization of research is an intricate process requiring an understanding of contextual factors. The study was conducted to assess enhancing factors and barriers of research utilization for malaria policy development in Malawi. Qualitative research approach was used through in-depth interviews with 39 key informants that included malaria researchers, policy makers, programme managers, and key stakeholders. Purposive sampling and snowballing techniques were used in identifying key informants. Interview transcripts were entered in QSR Nvivo 11 software for coding and analysis. Respondents identified global efforts as key in advancing knowledge translation, while local political will has been conducive for research utilization. Other factors were availability of research, availability of diverse local researchers and stakeholders supporting knowledge translation. While barriers included: lack of platforms for researcher-public engagement, politics, researchers' lack of communication skills, lack of research collaborations, funder driven research, unknown World Health Organization policy position, and the lack of a malaria research repository. Overall, the study identified facilitating factors to malaria research utilization for policy development in Malawi. These factors need to be systematically coordinated to address the identified barriers and improve on malaria research utilization in policy development. Malaria research can be key in the implementation of evidence-based interventions to reduce the malaria burden and assist in the paradigm shift from malaria control to elimination in Malawi.

Effects of soil amendments on bacterial wilt incidences and potato tuber yield across different environments in Malawi

This study investigated the effects of soil amendment on potato yield and incidences of bacterial wilt caused by Ralstonia solanacearum that can cause up to 80% yield loss in potato. The research was conducted at four research stations in Malawi during the 2020/21 and 2021/22 growing seasons, using a randomized complete block design (RCBD) with six treatments: lime, four Calciprill rates (CALC25%, CALC50%, CALC100%, and CALC150%), and NPK fertilizer (control). Data on soil properties, bacterial wilt incidence, and potato tuber yield were collected and analyzed using R programming. Soil fertility was found to be low, with a pH range of 4.4–6.05. Control resulted to significantly higher incidences of bacterial wilt at Kandiyani during 2020/21 (63.6%) and 2021/22 (34.6%) and at Lunyangwa during 2021/22 (20.4%) while lime and all levels of Calciprill led to relative incidence reduction (4%–89%) across sites and season, except CALC25% at Bembeke. Marketable yield showed interaction between amendments and season at Bvumbwe (p = 0.04), highest being 10.02 tha−1 in CALC150% during 2020/21 while non-marketable yield showed interaction at Lunyangwa (p = 0.02) highest being 3.9 tha−1 recorded in CALC150% during 2021/22. A significant negative correlation between bacterial wilt incidences and yield at all sites except Bembeke highlighted the importance of controlling bacterial wilt for yield improvement. The findings suggest that soil amendment through liming is an effective and sustainable approach for managing bacterial wilt and increasing potato yields. Further research on-farm conditions required to ensure the applicability of the findings for different sites

Specific IgG responses to <i>Salmonella Typhimurium lipopolysaccharide</i> and <i>Bordetella pertussis</i> toxin antigens in HEU and HUU children at different ages.

<p>Levels of specific IgG titres were measured against STM LPS (<b>3A</b>) and PT (<b>3B</b>) in HEU and HUU at three time points, 6 months (during CTX prophylaxis), 12 months (At stopping CTX prophylaxis) and 18 months (6 months after CTX prophylaxis). X-axis represents age of children in months. Black horizontal bars represent medians. Black lines represent differences in the median titres between groups at each time point. Blue lines represent a significant increase in levels of IgG titres from baseline in each group. Significant differences are indicated in asterices: <b><a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0121643#pone.0121643.g003" target="_blank">Fig. 3A</a></b> # (<i>p</i> = 0.0013), ## (<i>p</i> = 0.0263), ### (<i>p</i> = 0.0038), <b><a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0121643#pone.0121643.g003" target="_blank">Fig. 3B</a></b> *(<i>p</i> = 0.05), ** (<i>p</i> = 0.0108), *** (<i>p</i> = 0.0297)</p

Specific IgG responses to <i>P</i>. <i>falciparum</i> antigens in HEU and HUU children at different ages.

<p>Levels of specific IgG titres were measured against AMA-1 (<b>2A</b>), MSP-1₁₉ (<b>2B</b>), EBA-175RII (<b>2C</b>) and GLURP R2 (<b>2D</b>) in HEU and HUU at three time points, 6 months (during CTX prophylaxis), 12 months (At stopping CTX prophylaxis) and 18 months (6 months after CTX prophylaxis). X-axis represents age of children in months. Black horizontal bars represent medians. Black lines represent differences in the median titres between groups at each time point. Blue lines represent a significant change in levels of IgG titres from baseline in each group. Significant differences are indicated in asterices: <b><a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0121643#pone.0121643.g002" target="_blank">Fig. 2A</a></b> *(<i>p</i> = 0.0059), # (<i>p</i> < 0.0001), ## (<i>p</i> = 0.0015), <b><a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0121643#pone.0121643.g002" target="_blank">Fig. 2B</a></b> *(<i>p</i> = 0.037), <b><a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0121643#pone.0121643.g002" target="_blank">Fig. 2C</a></b> # (<i>p</i> = 0.0372), <b><a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0121643#pone.0121643.g002" target="_blank">Fig. 2D</a></b> # (<i>p</i> = 0.0107), ## (<i>p</i> = 0.0021).</p