132 research outputs found
Children’s heart disease in sub-Saharan Africa: Challenging the burden of disease
Children with heart disease in Africa have little or no access to treatment of any kind, and cardiac surgical services are virtually absent outside a handful of centres in a few of the wealthier nations. There is little reliable data concerning the prevalence of congenital or acquired heart disease in African children, but there is sufficient information to indicate that the burden of cardiac disease is vast. This major non-communicable disease is largely hidden, overshadowed by the incidence of communicable diseases. There is as yet little evidence of the hoped-for epidemiological transition toward non-communicable diseases amongst children in Africa. The burden of congenital heart disease is only part of the problem, with rheumatic heart disease (RHD) remaining the commonest cardiac problem, related to poor socioeconomic conditions. RHD is the most preventable form of cardiac disease, yet there is little preventive work being done. The many obstacles to developing paediatric cardiac care are discussed, and some possible ways forward are proposed
Producing elephant commodities for 'conservation hunting' in Namibian communal-area conservancies
Namibia's internationally acclaimed CBNRM program depends to a large extent on revenues generated from the trophy hunting of wild animals. The model is an important example of an increasingly 'neoliberal' global policy framework as applied to biodiversity conservation, its market-based approach and attendant socio-ecological effects having received in-depth engagement and critique from a political ecology perspective.Yet there remains a lack of detailed research concerning how these programs and their value frames are operationalized in practice. The article attempts to advance this literature through an empirical exploration of practices undertaken by diverse actors that work to produce and extract value from 'wild' natures, specifically elephants for 'conservation hunting' in Namibian communal-area conservancies. Conceptually, the article also contributes to an emerging body of work seeking to 'ecologise' political ecology, exploring the co-optation of lively elephants and other beyond-human entities in the production of economic value. 'Following' the elephant's interactions with other living entities, the article reveals the (non)human work and social practices that together 'labor' to produce commodified elephants that can be killed as trophies. We argue that 'undesirable encounters' such as crop raiding by elephants are both indicative of unequal power relations amongst CBNRM stakeholders and central to (re)producing dominant (neoliberal) value frames. The animal's spontaneous activities are co-opted into technocratic governance practices that legitimize the killing of elephants on environmental and economic grounds. In opening up the contested,contingent, and more-than-human nature of these social-ecological relations we also hope to contribute to possibilities for imagining more equitable and ecologically resilient conservation futures
Extrinsic bronchial compression by primary tuberculous adenopathy, simulating foreign-body aspiration
A 5-month-old boy was well until the day before admission, when he developed a cough. On the morning of admission he was irritable and his mother noticed a blue tinge to his lips during episodes of crying. This prompted her to bring him to the emergency unit at Red Cross Children's Hospital, where he was found to be distressed and cyanosed, with a respiratory rate of 60 beats per minute, a heart rate of 200/minute and alar flaring. His left chest showed decreased air entry, bronchial breathing and dullness to percussion. Oxygen saturation was 66%, improving to 88% on face-mask oxygen. His weight was on the 50th percentile. He was well hydrated, well perfused and had no significant background medical history. A mobile chest radiograph (Fig. 1) showed complete opacification of the left hemithorax, mediastinal deviation to the left and overexpansion of the right lung, which had herniated across the midline. A penetrated anteroposterior (AP) chest radiograph (Fig. 2) showed abrupt 'cut-off' of the left main bronchus
Regional cerebral oxygenation monitoring - intraoperative management in a patient with severe left ventricular dysfunction
Intraoperative near-infrared spectroscopy cerebral oxygenation monitoring assists intraoperative decision-making in environments without extracorporeal membrane oxygenation (ECMO), left ventricular assist device (LVAD) or access to cardiac transplantation. We report a case of an anomalous left coronary artery arising from the pulmonary artery (ALCAPA), undergoing cardiac surgery. A 4-month-old infant presented in extremis with cardiac failure. We discuss the pathophysiology and challenging intraoperative management of ALCAPA with extensive ischaemia and myocardial infarction
Population screening for colorectal cancer means getting FIT:the past, present, and future of colorectal cancer screening using the fecal immunochemical test for hemoglobin (FIT)
Fecal immunochemical tests for hemoglobin (FIT) are changing the manner in which colorectal cancer (CRC) is screened. Although these tests are being performed worldwide, why is this test different from its predecessors? What evidence supports its adoption? How can this evidence best be used? This review addresses these questions and provides an understanding of FIT theory and practices to expedite international efforts to implement the use of FIT in CRC screening
Deletion of parasite immune modulatory sequences combined with immune activating signals enhances vaccine mediated protection against filarial nematodes
<p>Background: Filarial nematodes are tissue-dwelling parasites that can be killed by Th2-driven immune effectors, but that have evolved to withstand immune attack and establish chronic infections by suppressing host immunity. As a consequence, the efficacy of a vaccine against filariasis may depend on its capacity to counter parasite-driven immunomodulation.</p>
<p>Methodology and Principal Findings: We immunised mice with DNA plasmids expressing functionally-inactivated forms of two immunomodulatory molecules expressed by the filarial parasite Litomosoides sigmodontis: the abundant larval transcript-1 (LsALT) and cysteine protease inhibitor-2 (LsCPI). The mutant proteins enhanced antibody and cytokine responses to live parasite challenge, and led to more leukocyte recruitment to the site of infection than their native forms. The immune response was further enhanced when the antigens were targeted to dendritic cells using a single chain Fv-αDEC205 antibody and co-administered with plasmids that enhance T helper 2 immunity (IL-4) and antigen-presenting cell recruitment (Flt3L, MIP-1α). Mice immunised simultaneously against the mutated forms of LsALT and LsCPI eliminated adult parasites faster and consistently reduced peripheral microfilaraemia. A multifactorial analysis of the immune response revealed that protection was strongly correlated with the production of parasite-specific IgG1 and with the numbers of leukocytes present at the site of infection.</p>
<p>Conclusions: We have developed a successful strategy for DNA vaccination against a nematode infection that specifically targets parasite-driven immunosuppression while simultaneously enhancing Th2 immune responses and parasite antigen presentation by dendritic cells.</p>
Micrometeoroid Events in LISA Pathfinder
The zodiacal dust complex, a population of dust and small particles that
pervades the Solar System, provides important insight into the formation and
dynamics of planets, comets, asteroids, and other bodies. Here we present a new
set of data obtained using a novel technique: direct measurements of momentum
transfer to a spacecraft from individual particle impacts. This technique is
made possible by the extreme precision of the instruments flown on the LISA
Pathfinder spacecraft, a technology demonstrator for a future space-based
gravitational wave observatory that operated near the first Sun-Earth Lagrange
point from early 2016 through Summer of 2017. Using a simple model of the
impacts and knowledge of the control system, we show that it is possible to
detect impacts and measure properties such as the transferred momentum (related
to the particle's mass and velocity), direction of travel, and location of
impact on the spacecraft. In this paper, we present the results of a systematic
search for impacts during 4348 hours of Pathfinder data. We report a total of
54 candidates with momenta ranging from 0.2 to
230. We furthermore make a comparison of these candidates
with models of micrometeoroid populations in the inner solar system including
those resulting from Jupiter-family comets, Oort-cloud comets, Hailey-type
comets, and Asteroids. We find that our measured population is consistent with
a population dominated by Jupiter-family comets with some evidence for a
smaller contribution from Hailey-type comets. This is in agreement with
consensus models of the zodiacal dust complex in the momentum range sampled by
LISA Pathfinder.Comment: 22 pages, 14 figures, accepted in Ap
Innate and adaptive type 2 immune cell responses in genetically controlled resistance to intestinal helminth infection
The nematode Heligmosomoides polygyrus is an excellent model for intestinal helminth parasitism. Infection in mice persists for varying lengths of time in different inbred strains, with CBA and C57BL/6 mice being fully susceptible, BALB/c partially so and SJL able to expel worms within 2–3 weeks of infection. We find that resistance correlates not only with the adaptive Th2 response, including IL-10 but with activation of innate lymphoid cell and macrophage populations. In addition, the titer and specificity range of the serum antibody response is maximal in resistant mice. In susceptible strains, Th2 responses were found to be counterbalanced by IFN-γ-producing CD4+ and CD8+ cells, but these are not solely responsible for susceptibility as mice deficient in either CD8+ T cells or IFN-γ remain unable to expel the parasites. Foxp3+ Treg numbers were comparable in all strains, but in the most resistant SJL strain, this population does not upregulate CD103 in infection, and in the lamina propria the frequency of Foxp3+CD103+ T cells is significantly lower than in susceptible mice. The more resistant SJL and BALB/c mice develop macrophage-rich IL-4Rα-dependent Type 2 granulomas around intestinal sites of larval invasion, and expression of alternative activation markers Arginase-1, Ch3L3 (Ym1) and RELM-α within the intestine and the peritoneal lavage was also strongly correlated with helminth elimination in these strains. Clodronate depletion of phagocytic cells compromises resistance of BALB/c mice and slows expulsion in the SJL strain. Thus, Type 2 immunity involves IL-4Rα-dependent innate cells including but not limited to a phagocyte population, the latter likely involving the action of specific antibodies
- …